[PATCH 0/29] Staging: Add yaffs2 filesystem

[PATCH 0/29] Staging: Add yaffs2 filesystem

[Tracey Dent]

The patch sets puts the yaffs2 filesystem in the staging directory.
It is all based on Charles git tree(http://github.com/cdhmanning/linux-yaffs-integration/).
Everything is compile tested and it builds.

This only the inital support and I will be sending more cleanup patches.

Greg can you add the patch set into your staging-next tree.
Also, It doesn't affect anything other than itself.

Thanks,

Tracey Dent

[PATCH 01/29] Staging: Add yaffs2 support

[Tracey Dent]

Changed files so that it could be compiled with yaffs2 enabled.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/Kconfig  |    2 ++
 drivers/staging/Makefile |    1 +
 2 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/drivers/staging/Kconfig b/drivers/staging/Kconfig
index f9c9c8a..7f4287a86 100644
--- a/drivers/staging/Kconfig
+++ b/drivers/staging/Kconfig
@@ -93,6 +93,8 @@ source "drivers/staging/pohmelfs/Kconfig"
 
 source "drivers/staging/autofs/Kconfig"
 
+source "drivers/staging/yaffs2/Kconfig"
+
 source "drivers/staging/phison/Kconfig"
 
 source "drivers/staging/line6/Kconfig"
diff --git a/drivers/staging/Makefile b/drivers/staging/Makefile
index a85074f..5f30c1b 100644
--- a/drivers/staging/Makefile
+++ b/drivers/staging/Makefile
@@ -31,6 +31,7 @@ obj-$(CONFIG_TRANZPORT)		+= frontier/
 obj-$(CONFIG_DREAM)		+= dream/
 obj-$(CONFIG_POHMELFS)		+= pohmelfs/
 obj-$(CONFIG_AUTOFS_FS)		+= autofs/
+obj-$(CONFIG_YAFFS_FS)		+= yaffs2/
 obj-$(CONFIG_IDE_PHISON)	+= phison/
 obj-$(CONFIG_LINE6_USB)		+= line6/
 obj-$(CONFIG_USB_SERIAL_QUATECH2)	+= serqt_usb2/
-- 
1.7.3.2.146.gca209

[PATCH 02/29] Staging: yaffs2: Add Makefile and Kconfig files

[Tracey Dent]

Add Makefile and Kconfig files so that we can start to compile the
filesystem.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/Kconfig  |  190 +++++++++++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/Makefile |   18 ++++
 2 files changed, 208 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/Kconfig
 create mode 100644 drivers/staging/yaffs2/Makefile

diff --git a/drivers/staging/yaffs2/Kconfig b/drivers/staging/yaffs2/Kconfig
new file mode 100644
index 0000000..7b3988c
--- /dev/null
+++ b/drivers/staging/yaffs2/Kconfig
@@ -0,0 +1,190 @@
+#
+# YAFFS file system configurations
+#
+
+config YAFFS_FS
+	tristate "YAFFS2 file system support"
+	default n
+	depends on MTD_BLOCK
+	select YAFFS_YAFFS1
+	select YAFFS_YAFFS2
+	help
+	  YAFFS2, or Yet Another Flash Filing System, is a filing system
+	  optimised for NAND Flash chips.
+
+	  To compile the YAFFS2 file system support as a module, choose M
+	  here: the module will be called yaffs2.
+
+	  If unsure, say N.
+
+	  Further information on YAFFS2 is available at
+	  <http://www.aleph1.co.uk/yaffs/>.
+
+config YAFFS_YAFFS1
+	bool "512 byte / page devices"
+	depends on YAFFS_FS
+	default y
+	help
+	  Enable YAFFS1 support -- yaffs for 512 byte / page devices
+
+	  Not needed for 2K-page devices.
+
+	  If unsure, say Y.
+
+config YAFFS_9BYTE_TAGS
+	bool "Use older-style on-NAND data format with pageStatus byte"
+	depends on YAFFS_YAFFS1
+	default n
+	help
+
+	  Older-style on-NAND data format has a "pageStatus" byte to record
+	  chunk/page state.  This byte is zero when the page is discarded.
+	  Choose this option if you have existing on-NAND data using this
+	  format that you need to continue to support.  New data written
+	  also uses the older-style format.  Note: Use of this option
+	  generally requires that MTD's oob layout be adjusted to use the
+	  older-style format.  See notes on tags formats and MTD versions
+	  in yaffs_mtdif1.c.
+
+	  If unsure, say N.
+
+config YAFFS_DOES_ECC
+	bool "Lets Yaffs do its own ECC"
+	depends on YAFFS_FS && YAFFS_YAFFS1 && !YAFFS_9BYTE_TAGS
+	default n
+	help
+	  This enables Yaffs to use its own ECC functions instead of using
+	  the ones from the generic MTD-NAND driver.
+
+	  If unsure, say N.
+
+config YAFFS_ECC_WRONG_ORDER
+	bool "Use the same ecc byte order as Steven Hill's nand_ecc.c"
+	depends on YAFFS_FS && YAFFS_DOES_ECC && !YAFFS_9BYTE_TAGS
+	default n
+	help
+	  This makes yaffs_ecc.c use the same ecc byte order as Steven
+	  Hill's nand_ecc.c. If not set, then you get the same ecc byte
+	  order as SmartMedia.
+
+	  If unsure, say N.
+
+config YAFFS_YAFFS2
+	bool "2048 byte (or larger) / page devices"
+	depends on YAFFS_FS
+	default y
+	help
+	  Enable YAFFS2 support -- yaffs for >= 2K bytes per page devices
+
+	  If unsure, say Y.
+
+config YAFFS_AUTO_YAFFS2
+	bool "Autoselect yaffs2 format"
+	depends on YAFFS_YAFFS2
+	default y
+	help
+	  Without this, you need to explicitely use yaffs2 as the file
+	  system type. With this, you can say "yaffs" and yaffs or yaffs2
+	  will be used depending on the device page size (yaffs on
+	  512-byte page devices, yaffs2 on 2K page devices).
+
+	  If unsure, say Y.
+
+config YAFFS_DISABLE_TAGS_ECC
+	bool "Disable YAFFS from doing ECC on tags by default"
+	depends on YAFFS_FS && YAFFS_YAFFS2
+	default n
+	help
+	  This defaults Yaffs to using its own ECC calculations on tags instead of
+	  just relying on the MTD.
+	  This behavior can also be overridden with tags_ecc_on and
+	  tags_ecc_off mount options.
+
+	  If unsure, say N.
+
+
+config YAFFS_DISABLE_WIDE_TNODES
+	bool "Turn off wide tnodes"
+	depends on YAFFS_FS
+	default n
+	help
+	  Wide tnodes are only used for NAND arrays >=32MB for 512-byte
+	  page devices and >=128MB for 2k page devices. They use slightly
+	  more RAM but are faster since they eliminate chunk group
+	  searching.
+
+	  Setting this to 'y' will force tnode width to 16 bits and save
+	  memory but make large arrays slower.
+
+	  If unsure, say N.
+
+config YAFFS_ALWAYS_CHECK_CHUNK_ERASED
+	bool "Force chunk erase check"
+	depends on YAFFS_FS
+	default n
+	help
+          Normally YAFFS only checks chunks before writing until an erased
+	  chunk is found. This helps to detect any partially written
+	  chunks that might have happened due to power loss.
+
+	  Enabling this forces on the test that chunks are erased in flash
+	  before writing to them. This takes more time but is potentially
+	  a bit more secure.
+
+	  Suggest setting Y during development and ironing out driver
+	  issues etc. Suggest setting to N if you want faster writing.
+
+	  If unsure, say Y.
+
+config YAFFS_SHORT_NAMES_IN_RAM
+	bool "Cache short names in RAM"
+	depends on YAFFS_FS
+	default y
+	help
+	  If this config is set, then short names are stored with the
+	  yaffs_Object.  This costs an extra 16 bytes of RAM per object,
+	  but makes look-ups faster.
+
+	  If unsure, say Y.
+
+config YAFFS_EMPTY_LOST_AND_FOUND
+	bool "Empty lost and found on boot"
+	depends on YAFFS_FS
+	default n
+	help
+	  If this is enabled then the contents of lost and found is
+	  automatically dumped at mount.
+
+	  If unsure, say N.
+
+config YAFFS_DISABLE_BLOCK_REFRESHING
+	bool "Disable yaffs2 block refreshing"
+	depends on YAFFS_FS
+	default n
+	help
+	 If this is set, then block refreshing is disabled.
+	 Block refreshing infrequently refreshes the oldest block in
+	 a yaffs2 file system. This mechanism helps to refresh flash to
+	 mitigate against data loss. This is particularly useful for MLC.
+
+	  If unsure, say N.
+
+config YAFFS_DISABLE_BACKGROUND
+	bool "Disable yaffs2 background processing"
+	depends on YAFFS_FS
+	default n
+	help
+	 If this is set, then background processing is disabled.
+	 Background processing makes many foreground activities faster.
+
+	  If unsure, say N.
+
+config YAFFS_XATTR
+	bool "Enable yaffs2 xattr support"
+	depends on YAFFS_FS
+	default y
+	help
+	 If this is set then yaffs2 will provide xattr support.
+	 If unsure, say Y.
+
+
diff --git a/drivers/staging/yaffs2/Makefile b/drivers/staging/yaffs2/Makefile
new file mode 100644
index 0000000..ac4a72d
--- /dev/null
+++ b/drivers/staging/yaffs2/Makefile
@@ -0,0 +1,18 @@
+#
+# Makefile for the linux YAFFS filesystem routines.
+#
+
+obj-$(CONFIG_YAFFS_FS) += yaffs.o
+
+yaffs-y := yaffs_ecc.o yaffs_vfs_glue.o yaffs_guts.o yaffs_checkptrw.o
+yaffs-y += yaffs_packedtags1.o yaffs_packedtags2.o yaffs_nand.o
+yaffs-y += yaffs_tagscompat.o yaffs_tagsvalidity.o
+yaffs-y += yaffs_mtdif.o yaffs_mtdif1.o yaffs_mtdif2.o
+yaffs-y += yaffs_nameval.o
+yaffs-y += yaffs_allocator.o
+yaffs-y += yaffs_yaffs1.o
+yaffs-y += yaffs_yaffs2.o
+yaffs-y += yaffs_bitmap.o
+yaffs-y += yaffs_verify.o
+
+
-- 
1.7.3.2.146.gca209

[PATCH 03/29] Staging: yaffs2: devextras.h: Add file

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/devextras.h |  101 ++++++++++++++++++++++++++++++++++++
 1 files changed, 101 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/devextras.h

diff --git a/drivers/staging/yaffs2/devextras.h b/drivers/staging/yaffs2/devextras.h
new file mode 100644
index 0000000..ce30c82
--- /dev/null
+++ b/drivers/staging/yaffs2/devextras.h
@@ -0,0 +1,101 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+/*
+ * This file is just holds extra declarations of macros that would normally
+ * be providesd in the Linux kernel. These macros have been written from
+ * scratch but are functionally equivalent to the Linux ones.
+ *
+ */
+
+#ifndef __EXTRAS_H__
+#define __EXTRAS_H__
+
+
+#include "yportenv.h"
+
+#if !(defined __KERNEL__)
+
+/* Definition of types */
+typedef unsigned char __u8;
+typedef unsigned short __u16;
+typedef unsigned __u32;
+
+#endif
+
+
+#if !(defined __KERNEL__)
+
+
+#ifndef WIN32
+#include <sys/stat.h>
+#endif
+
+
+#ifdef CONFIG_YAFFS_PROVIDE_DEFS
+/* File types */
+
+
+#define DT_UNKNOWN	0
+#define DT_FIFO		1
+#define DT_CHR		2
+#define DT_DIR		4
+#define DT_BLK		6
+#define DT_REG		8
+#define DT_LNK		10
+#define DT_SOCK		12
+#define DT_WHT		14
+
+
+#ifndef WIN32
+#include <sys/stat.h>
+#endif
+
+/*
+ * Attribute flags.  These should be or-ed together to figure out what
+ * has been changed!
+ */
+#define ATTR_MODE	1
+#define ATTR_UID	2
+#define ATTR_GID	4
+#define ATTR_SIZE	8
+#define ATTR_ATIME	16
+#define ATTR_MTIME	32
+#define ATTR_CTIME	64
+
+struct iattr {
+	unsigned int ia_valid;
+	unsigned ia_mode;
+	unsigned ia_uid;
+	unsigned ia_gid;
+	unsigned ia_size;
+	unsigned ia_atime;
+	unsigned ia_mtime;
+	unsigned ia_ctime;
+	unsigned int ia_attr_flags;
+};
+
+#endif
+
+#else
+
+#include <linux/types.h>
+#include <linux/fs.h>
+#include <linux/stat.h>
+
+#endif
+
+
+#endif
-- 
1.7.3.2.146.gca209

Re: [PATCH 03/29] Staging: yaffs2: devextras.h: Add file

[Pekka Enberg]

On Mon, Nov 1, 2010 at 8:40 PM, Tracey Dent <tdent48227@gmail.com> wrote:
> Adding files to yaffs2 directory.
>
> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> ---
>  drivers/staging/yaffs2/devextras.h |  101 ++++++++++++++++++++++++++++++++++++
>  1 files changed, 101 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/yaffs2/devextras.h
>
> diff --git a/drivers/staging/yaffs2/devextras.h b/drivers/staging/yaffs2/devextras.h
> new file mode 100644
> index 0000000..ce30c82
> --- /dev/null
> +++ b/drivers/staging/yaffs2/devextras.h
> @@ -0,0 +1,101 @@
> +/*
> + * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
> + *
> + * Copyright (C) 2002-2010 Aleph One Ltd.
> + *   for Toby Churchill Ltd and Brightstar Engineering
> + *
> + * Created by Charles Manning <charles@aleph1.co.uk>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU Lesser General Public License version 2.1 as
> + * published by the Free Software Foundation.
> + *
> + * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
> + */
> +
> +/*
> + * This file is just holds extra declarations of macros that would normally
> + * be providesd in the Linux kernel. These macros have been written from
> + * scratch but are functionally equivalent to the Linux ones.
> + *
> + */

Seriously, you're adding WIN32 #ifdefs. Why do we want to merge this
header to mainline?
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Re: [PATCH 03/29] Staging: yaffs2: devextras.h: Add file

[Greg KH]

On Mon, Nov 01, 2010 at 08:56:27PM +0200, Pekka Enberg wrote:
> On Mon, Nov 1, 2010 at 8:40 PM, Tracey Dent <tdent48227@gmail.com> wrote:
> > Adding files to yaffs2 directory.
> >
> > Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> > ---
> > ?drivers/staging/yaffs2/devextras.h | ?101 ++++++++++++++++++++++++++++++++++++
> > ?1 files changed, 101 insertions(+), 0 deletions(-)
> > ?create mode 100644 drivers/staging/yaffs2/devextras.h
> >
> > diff --git a/drivers/staging/yaffs2/devextras.h b/drivers/staging/yaffs2/devextras.h
> > new file mode 100644
> > index 0000000..ce30c82
> > --- /dev/null
> > +++ b/drivers/staging/yaffs2/devextras.h
> > @@ -0,0 +1,101 @@
> > +/*
> > + * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
> > + *
> > + * Copyright (C) 2002-2010 Aleph One Ltd.
> > + * ? for Toby Churchill Ltd and Brightstar Engineering
> > + *
> > + * Created by Charles Manning <charles@aleph1.co.uk>
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU Lesser General Public License version 2.1 as
> > + * published by the Free Software Foundation.
> > + *
> > + * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
> > + */
> > +
> > +/*
> > + * This file is just holds extra declarations of macros that would normally
> > + * be providesd in the Linux kernel. These macros have been written from
> > + * scratch but are functionally equivalent to the Linux ones.
> > + *
> > + */
> 
> Seriously, you're adding WIN32 #ifdefs. Why do we want to merge this
> header to mainline?

It would be in staging, and removed before going to the main portion of
the tree.  This happens all the time...

thanks,

greg k-h

[PATCH 04/29] Staging: yaffs2: moduleconfig.h: Add file

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/moduleconfig.h |   86 +++++++++++++++++++++++++++++++++
 1 files changed, 86 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/moduleconfig.h

diff --git a/drivers/staging/yaffs2/moduleconfig.h b/drivers/staging/yaffs2/moduleconfig.h
new file mode 100644
index 0000000..4b4d642
--- /dev/null
+++ b/drivers/staging/yaffs2/moduleconfig.h
@@ -0,0 +1,86 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Martin Fouts <Martin.Fouts@palmsource.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_CONFIG_H__
+#define __YAFFS_CONFIG_H__
+
+#ifdef YAFFS_OUT_OF_TREE
+
+/* DO NOT UNSET THESE THREE. YAFFS2 will not compile if you do. */
+#define CONFIG_YAFFS_FS
+#define CONFIG_YAFFS_YAFFS1
+#define CONFIG_YAFFS_YAFFS2
+
+/* These options are independent of each other.  Select those that matter. */
+
+/* Default: Not selected */
+/* Meaning: Yaffs does its own ECC, rather than using MTD ECC */
+/* #define CONFIG_YAFFS_DOES_ECC */
+
+/* Default: Selected */
+/* Meaning: Yaffs does its own ECC on tags for packed tags rather than use mtd */
+#define CONFIG_YAFFS_DOES_TAGS_ECC
+
+/* Default: Not selected */
+/* Meaning: ECC byte order is 'wrong'.  Only meaningful if */
+/*          CONFIG_YAFFS_DOES_ECC is set */
+/* #define CONFIG_YAFFS_ECC_WRONG_ORDER */
+
+/* Default: Not selected */
+/* Meaning: Always test whether chunks are erased before writing to them.
+	    Use during mtd debugging and init. */
+/* #define CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED */
+
+/* Default: Not Selected */
+/* Meaning: At mount automatically empty all files from lost and found. */
+/* This is done to fix an old problem where rmdir was not checking for an */
+/* empty directory. This can also be achieved with a mount option. */
+#define CONFIG_YAFFS_EMPTY_LOST_AND_FOUND
+
+/* Default: Selected */
+/* Meaning: Cache short names, taking more RAM, but faster look-ups */
+#define CONFIG_YAFFS_SHORT_NAMES_IN_RAM
+
+/* Default: Unselected */
+/* Meaning: Select to disable block refreshing. */
+/* Block Refreshing periodically rewrites the oldest block. */
+/* #define CONFIG_DISABLE_BLOCK_REFRESHING */
+
+/* Default: Unselected */
+/* Meaning: Select to disable background processing */
+/* #define CONFIG_DISABLE_BACKGROUND */
+
+
+/* Default: Selected */
+/* Meaning: Enable XATTR support */
+#define CONFIG_YAFFS_XATTR
+
+/*
+Older-style on-NAND data format has a "page_status" byte to record
+chunk/page state.  This byte is zeroed when the page is discarded.
+Choose this option if you have existing on-NAND data in this format
+that you need to continue to support.  New data written also uses the
+older-style format.
+Note: Use of this option generally requires that MTD's oob layout be
+adjusted to use the older-style format.  See notes on tags formats and
+MTD versions in yaffs_mtdif1.c.
+*/
+/* Default: Not selected */
+/* Meaning: Use older-style on-NAND data format with page_status byte */
+/* #define CONFIG_YAFFS_9BYTE_TAGS */
+
+#endif /* YAFFS_OUT_OF_TREE */
+
+#endif /* __YAFFS_CONFIG_H__ */
-- 
1.7.3.2.146.gca209

Re: [PATCH 04/29] Staging: yaffs2: moduleconfig.h: Add file

[Pekka Enberg]

On Mon, Nov 1, 2010 at 8:40 PM, Tracey Dent <tdent48227@gmail.com> wrote:
> Adding files to yaffs2 directory.
>
> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> ---
>  drivers/staging/yaffs2/moduleconfig.h |   86 +++++++++++++++++++++++++++++++++
>  1 files changed, 86 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/yaffs2/moduleconfig.h
>
> diff --git a/drivers/staging/yaffs2/moduleconfig.h b/drivers/staging/yaffs2/moduleconfig.h
> new file mode 100644
> index 0000000..4b4d642
> --- /dev/null
> +++ b/drivers/staging/yaffs2/moduleconfig.h
> @@ -0,0 +1,86 @@
> +/*
> + * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
> + *
> + * Copyright (C) 2002-2010 Aleph One Ltd.
> + *   for Toby Churchill Ltd and Brightstar Engineering
> + *
> + * Created by Martin Fouts <Martin.Fouts@palmsource.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU Lesser General Public License version 2.1 as
> + * published by the Free Software Foundation.
> + *
> + * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
> + */
> +
> +#ifndef __YAFFS_CONFIG_H__
> +#define __YAFFS_CONFIG_H__
> +
> +#ifdef YAFFS_OUT_OF_TREE

You probably want to drop this header as well...
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Re: [PATCH 04/29] Staging: yaffs2: moduleconfig.h: Add file

[Tracey Dent]

On 11/1/10, Pekka Enberg <penberg@kernel.org> wrote:
> On Mon, Nov 1, 2010 at 8:40 PM, Tracey Dent <tdent48227@gmail.com> wrote:
>> Adding files to yaffs2 directory.
>>
>> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
>> ---
>>  drivers/staging/yaffs2/moduleconfig.h |   86
>> +++++++++++++++++++++++++++++++++
>>  1 files changed, 86 insertions(+), 0 deletions(-)
>>  create mode 100644 drivers/staging/yaffs2/moduleconfig.h
>>
>> diff --git a/drivers/staging/yaffs2/moduleconfig.h
>> b/drivers/staging/yaffs2/moduleconfig.h
>> new file mode 100644
>> index 0000000..4b4d642
>> --- /dev/null
>> +++ b/drivers/staging/yaffs2/moduleconfig.h
>> @@ -0,0 +1,86 @@
>> +/*
>> + * YAFFS: Yet another Flash File System . A NAND-flash specific file
>> system.
>> + *
>> + * Copyright (C) 2002-2010 Aleph One Ltd.
>> + *   for Toby Churchill Ltd and Brightstar Engineering
>> + *
>> + * Created by Martin Fouts <Martin.Fouts@palmsource.com>
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU Lesser General Public License version
>> 2.1 as
>> + * published by the Free Software Foundation.
>> + *
>> + * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
>> + */
>> +
>> +#ifndef __YAFFS_CONFIG_H__
>> +#define __YAFFS_CONFIG_H__
>> +
>> +#ifdef YAFFS_OUT_OF_TREE
>
> You probably want to drop this header as well...
>
 Yes, I was going to make up a clean up patch set when or if this gets merge.

[PATCH 05/29] Staging: yaffs2: yaffs_allocator: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_allocator.c |  408 ++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_allocator.h |   30 +++
 2 files changed, 438 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_allocator.c
 create mode 100644 drivers/staging/yaffs2/yaffs_allocator.h

diff --git a/drivers/staging/yaffs2/yaffs_allocator.c b/drivers/staging/yaffs2/yaffs_allocator.c
new file mode 100644
index 0000000..024ee2a
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_allocator.c
@@ -0,0 +1,408 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+
+
+#include "yaffs_allocator.h"
+#include "yaffs_guts.h"
+#include "yaffs_trace.h"
+#include "yportenv.h"
+
+#ifdef CONFIG_YAFFS_YMALLOC_ALLOCATOR
+
+void yaffs_deinit_raw_tnodes_and_objs(yaffs_dev_t *dev)
+{
+	dev = dev;
+}
+
+void yaffs_init_raw_tnodes_and_objs(yaffs_dev_t *dev)
+{
+	dev = dev;
+}
+
+yaffs_tnode_t *yaffs_alloc_raw_tnode(yaffs_dev_t *dev)
+{
+	return (yaffs_tnode_t *)YMALLOC(dev->tnode_size);
+}
+
+void yaffs_free_raw_tnode(yaffs_dev_t *dev, yaffs_tnode_t *tn)
+{
+	dev = dev;
+	YFREE(tn);
+}
+
+void yaffs_init_raw_objs(yaffs_dev_t *dev)
+{
+	dev = dev;
+}
+
+void yaffs_deinit_raw_objs(yaffs_dev_t *dev)
+{
+	dev = dev;
+}
+
+yaffs_obj_t *yaffs_alloc_raw_obj(yaffs_dev_t *dev)
+{
+	dev = dev;
+	return (yaffs_obj_t *) YMALLOC(sizeof(yaffs_obj_t));
+}
+
+
+void yaffs_free_raw_obj(yaffs_dev_t *dev, yaffs_obj_t *obj)
+{
+
+	dev = dev;
+	YFREE(obj);
+}
+
+#else
+
+struct yaffs_tnode_list {
+	struct yaffs_tnode_list *next;
+	yaffs_tnode_t *tnodes;
+};
+
+typedef struct yaffs_tnode_list yaffs_tnodelist_t;
+
+struct yaffs_obj_list_struct {
+	yaffs_obj_t *objects;
+	struct yaffs_obj_list_struct *next;
+};
+
+typedef struct yaffs_obj_list_struct yaffs_obj_list;
+
+
+struct yaffs_AllocatorStruct {
+	int n_tnodesCreated;
+	yaffs_tnode_t *freeTnodes;
+	int nFreeTnodes;
+	yaffs_tnodelist_t *allocatedTnodeList;
+
+	int n_objCreated;
+	yaffs_obj_t *freeObjects;
+	int nFreeObjects;
+
+	yaffs_obj_list *allocated_list;
+};
+
+typedef struct yaffs_AllocatorStruct yaffs_Allocator;
+
+
+static void yaffs_deinit_raw_tnodes(yaffs_dev_t *dev)
+{
+
+	yaffs_Allocator *allocator = (yaffs_Allocator *)dev->allocator;
+
+	yaffs_tnodelist_t *tmp;
+
+	if(!allocator){
+		YBUG();
+		return;
+	}
+
+	while (allocator->allocatedTnodeList) {
+		tmp = allocator->allocatedTnodeList->next;
+
+		YFREE(allocator->allocatedTnodeList->tnodes);
+		YFREE(allocator->allocatedTnodeList);
+		allocator->allocatedTnodeList = tmp;
+
+	}
+
+	allocator->freeTnodes = NULL;
+	allocator->nFreeTnodes = 0;
+	allocator->n_tnodesCreated = 0;
+}
+
+static void yaffs_init_raw_tnodes(yaffs_dev_t *dev)
+{
+	yaffs_Allocator *allocator = dev->allocator;
+
+	if(allocator){
+		allocator->allocatedTnodeList = NULL;
+		allocator->freeTnodes = NULL;
+		allocator->nFreeTnodes = 0;
+		allocator->n_tnodesCreated = 0;
+	} else
+		YBUG();
+}
+
+static int yaffs_create_tnodes(yaffs_dev_t *dev, int n_tnodes)
+{
+	yaffs_Allocator *allocator = (yaffs_Allocator *)dev->allocator;
+	int i;
+	yaffs_tnode_t *newTnodes;
+	__u8 *mem;
+	yaffs_tnode_t *curr;
+	yaffs_tnode_t *next;
+	yaffs_tnodelist_t *tnl;
+
+	if(!allocator){
+		YBUG();
+		return YAFFS_FAIL;
+	}
+
+	if (n_tnodes < 1)
+		return YAFFS_OK;
+
+
+	/* make these things */
+
+	newTnodes = YMALLOC(n_tnodes * dev->tnode_size);
+	mem = (__u8 *)newTnodes;
+
+	if (!newTnodes) {
+		T(YAFFS_TRACE_ERROR,
+			(TSTR("yaffs: Could not allocate Tnodes" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	/* New hookup for wide tnodes */
+	for (i = 0; i < n_tnodes - 1; i++) {
+		curr = (yaffs_tnode_t *) &mem[i * dev->tnode_size];
+		next = (yaffs_tnode_t *) &mem[(i+1) * dev->tnode_size];
+		curr->internal[0] = next;
+	}
+
+	curr = (yaffs_tnode_t *) &mem[(n_tnodes - 1) * dev->tnode_size];
+	curr->internal[0] = allocator->freeTnodes;
+	allocator->freeTnodes = (yaffs_tnode_t *)mem;
+
+	allocator->nFreeTnodes += n_tnodes;
+	allocator->n_tnodesCreated += n_tnodes;
+
+	/* Now add this bunch of tnodes to a list for freeing up.
+	 * NB If we can't add this to the management list it isn't fatal
+	 * but it just means we can't free this bunch of tnodes later.
+	 */
+
+	tnl = YMALLOC(sizeof(yaffs_tnodelist_t));
+	if (!tnl) {
+		T(YAFFS_TRACE_ERROR,
+		  (TSTR
+		   ("yaffs: Could not add tnodes to management list" TENDSTR)));
+		   return YAFFS_FAIL;
+	} else {
+		tnl->tnodes = newTnodes;
+		tnl->next = allocator->allocatedTnodeList;
+		allocator->allocatedTnodeList = tnl;
+	}
+
+	T(YAFFS_TRACE_ALLOCATE, (TSTR("yaffs: Tnodes added" TENDSTR)));
+
+	return YAFFS_OK;
+}
+
+
+yaffs_tnode_t *yaffs_alloc_raw_tnode(yaffs_dev_t *dev)
+{
+	yaffs_Allocator *allocator = (yaffs_Allocator *)dev->allocator;
+	yaffs_tnode_t *tn = NULL;
+
+	if(!allocator){
+		YBUG();
+		return NULL;
+	}
+
+	/* If there are none left make more */
+	if (!allocator->freeTnodes)
+		yaffs_create_tnodes(dev, YAFFS_ALLOCATION_NTNODES);
+
+	if (allocator->freeTnodes) {
+		tn = allocator->freeTnodes;
+		allocator->freeTnodes = allocator->freeTnodes->internal[0];
+		allocator->nFreeTnodes--;
+	}
+
+	return tn;
+}
+
+/* FreeTnode frees up a tnode and puts it back on the free list */
+void yaffs_free_raw_tnode(yaffs_dev_t *dev, yaffs_tnode_t *tn)
+{
+	yaffs_Allocator *allocator = dev->allocator;
+
+	if(!allocator){
+		YBUG();
+		return;
+	}
+
+	if (tn) {
+		tn->internal[0] = allocator->freeTnodes;
+		allocator->freeTnodes = tn;
+		allocator->nFreeTnodes++;
+	}
+	dev->checkpoint_blocks_required = 0; /* force recalculation*/
+}
+
+
+
+static void yaffs_init_raw_objs(yaffs_dev_t *dev)
+{
+	yaffs_Allocator *allocator = dev->allocator;
+
+	if(allocator) {
+		allocator->allocated_list = NULL;
+		allocator->freeObjects = NULL;
+		allocator->nFreeObjects = 0;
+	} else
+		YBUG();
+}
+
+static void yaffs_deinit_raw_objs(yaffs_dev_t *dev)
+{
+	yaffs_Allocator *allocator = dev->allocator;
+	yaffs_obj_list *tmp;
+
+	if(!allocator){
+		YBUG();
+		return;
+	}
+
+	while (allocator->allocated_list) {
+		tmp = allocator->allocated_list->next;
+		YFREE(allocator->allocated_list->objects);
+		YFREE(allocator->allocated_list);
+
+		allocator->allocated_list = tmp;
+	}
+
+	allocator->freeObjects = NULL;
+	allocator->nFreeObjects = 0;
+	allocator->n_objCreated = 0;
+}
+
+
+static int yaffs_create_free_objs(yaffs_dev_t *dev, int n_obj)
+{
+	yaffs_Allocator *allocator = dev->allocator;
+
+	int i;
+	yaffs_obj_t *newObjects;
+	yaffs_obj_list *list;
+
+	if(!allocator){
+		YBUG();
+		return YAFFS_FAIL;
+	}
+
+	if (n_obj < 1)
+		return YAFFS_OK;
+
+	/* make these things */
+	newObjects = YMALLOC(n_obj * sizeof(yaffs_obj_t));
+	list = YMALLOC(sizeof(yaffs_obj_list));
+
+	if (!newObjects || !list) {
+		if (newObjects){
+			YFREE(newObjects);
+			newObjects = NULL;
+		}
+		if (list){
+			YFREE(list);
+			list = NULL;
+		}
+		T(YAFFS_TRACE_ALLOCATE,
+		  (TSTR("yaffs: Could not allocate more objects" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	/* Hook them into the free list */
+	for (i = 0; i < n_obj - 1; i++) {
+		newObjects[i].siblings.next =
+				(struct ylist_head *)(&newObjects[i + 1]);
+	}
+
+	newObjects[n_obj - 1].siblings.next = (void *)allocator->freeObjects;
+	allocator->freeObjects = newObjects;
+	allocator->nFreeObjects += n_obj;
+	allocator->n_objCreated += n_obj;
+
+	/* Now add this bunch of Objects to a list for freeing up. */
+
+	list->objects = newObjects;
+	list->next = allocator->allocated_list;
+	allocator->allocated_list = list;
+
+	return YAFFS_OK;
+}
+
+yaffs_obj_t *yaffs_alloc_raw_obj(yaffs_dev_t *dev)
+{
+	yaffs_obj_t *obj = NULL;
+	yaffs_Allocator *allocator = dev->allocator;
+
+	if(!allocator) {
+		YBUG();
+		return obj;
+	}
+
+	/* If there are none left make more */
+	if (!allocator->freeObjects)
+		yaffs_create_free_objs(dev, YAFFS_ALLOCATION_NOBJECTS);
+
+	if (allocator->freeObjects) {
+		obj = allocator->freeObjects;
+		allocator->freeObjects =
+			(yaffs_obj_t *) (allocator->freeObjects->siblings.next);
+		allocator->nFreeObjects--;
+	}
+
+	return obj;
+}
+
+
+void yaffs_free_raw_obj(yaffs_dev_t *dev, yaffs_obj_t *obj)
+{
+
+	yaffs_Allocator *allocator = dev->allocator;
+
+	if(!allocator)
+		YBUG();
+	else {
+		/* Link into the free list. */
+		obj->siblings.next = (struct ylist_head *)(allocator->freeObjects);
+		allocator->freeObjects = obj;
+		allocator->nFreeObjects++;
+	}
+}
+
+void yaffs_deinit_raw_tnodes_and_objs(yaffs_dev_t *dev)
+{
+	if(dev->allocator){
+		yaffs_deinit_raw_tnodes(dev);
+		yaffs_deinit_raw_objs(dev);
+
+		YFREE(dev->allocator);
+		dev->allocator=NULL;
+	} else
+		YBUG();
+}
+
+void yaffs_init_raw_tnodes_and_objs(yaffs_dev_t *dev)
+{
+	yaffs_Allocator *allocator;
+
+	if(!dev->allocator){
+		allocator = YMALLOC(sizeof(yaffs_Allocator));
+		if(allocator){
+			dev->allocator = allocator;
+			yaffs_init_raw_tnodes(dev);
+			yaffs_init_raw_objs(dev);
+		}
+	} else
+		YBUG();
+}
+
+
+#endif
diff --git a/drivers/staging/yaffs2/yaffs_allocator.h b/drivers/staging/yaffs2/yaffs_allocator.h
new file mode 100644
index 0000000..777f3b0
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_allocator.h
@@ -0,0 +1,30 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_ALLOCATOR_H__
+#define __YAFFS_ALLOCATOR_H__
+
+#include "yaffs_guts.h"
+
+void yaffs_init_raw_tnodes_and_objs(yaffs_dev_t *dev);
+void yaffs_deinit_raw_tnodes_and_objs(yaffs_dev_t *dev);
+
+yaffs_tnode_t *yaffs_alloc_raw_tnode(yaffs_dev_t *dev);
+void yaffs_free_raw_tnode(yaffs_dev_t *dev, yaffs_tnode_t *tn);
+
+yaffs_obj_t *yaffs_alloc_raw_obj(yaffs_dev_t *dev);
+void yaffs_free_raw_obj(yaffs_dev_t *dev, yaffs_obj_t *obj);
+
+#endif
-- 
1.7.3.2.146.gca209

Re: [PATCH 05/29] Staging: yaffs2: yaffs_allocator: Add files

[Pekka Enberg]

On Mon, Nov 1, 2010 at 8:40 PM, Tracey Dent <tdent48227@gmail.com> wrote:
> Adding files to yaffs2 directory.
>
> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> ---
>  drivers/staging/yaffs2/yaffs_allocator.c |  408 ++++++++++++++++++++++++++++++
>  drivers/staging/yaffs2/yaffs_allocator.h |   30 +++
>  2 files changed, 438 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/yaffs2/yaffs_allocator.c
>  create mode 100644 drivers/staging/yaffs2/yaffs_allocator.h
>
> diff --git a/drivers/staging/yaffs2/yaffs_allocator.c b/drivers/staging/yaffs2/yaffs_allocator.c
> new file mode 100644
> index 0000000..024ee2a
> --- /dev/null
> +++ b/drivers/staging/yaffs2/yaffs_allocator.c
> @@ -0,0 +1,408 @@
> +/*
> + * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
> + *
> + * Copyright (C) 2002-2010 Aleph One Ltd.
> + *   for Toby Churchill Ltd and Brightstar Engineering
> + *
> + * Created by Charles Manning <charles@aleph1.co.uk>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +
> +
> +#include "yaffs_allocator.h"
> +#include "yaffs_guts.h"
> +#include "yaffs_trace.h"
> +#include "yportenv.h"
> +
> +#ifdef CONFIG_YAFFS_YMALLOC_ALLOCATOR
> +
> +void yaffs_deinit_raw_tnodes_and_objs(yaffs_dev_t *dev)
> +{
> +       dev = dev;
> +}
> +
> +void yaffs_init_raw_tnodes_and_objs(yaffs_dev_t *dev)
> +{
> +       dev = dev;
> +}
> +
> +yaffs_tnode_t *yaffs_alloc_raw_tnode(yaffs_dev_t *dev)
> +{
> +       return (yaffs_tnode_t *)YMALLOC(dev->tnode_size);
> +}
> +
> +void yaffs_free_raw_tnode(yaffs_dev_t *dev, yaffs_tnode_t *tn)
> +{
> +       dev = dev;
> +       YFREE(tn);
> +}

So you have your own dynamic memory allocator? What's wrong with kmalloc()?
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Re: [PATCH 05/29] Staging: yaffs2: yaffs_allocator: Add files

[Charles Manning]

On Tuesday 02 November 2010 07:58:49 Pekka Enberg wrote:
> On Mon, Nov 1, 2010 at 8:40 PM, Tracey Dent <tdent48227@gmail.com> wrote:
> > Adding files to yaffs2 directory.
> >
> > Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> > ---
> >  drivers/staging/yaffs2/yaffs_allocator.c |  408
> > ++++++++++++++++++++++++++++++ drivers/staging/yaffs2/yaffs_allocator.h |
> >   30 +++
> >  2 files changed, 438 insertions(+), 0 deletions(-)
> >  create mode 100644 drivers/staging/yaffs2/yaffs_allocator.c
> >  create mode 100644 drivers/staging/yaffs2/yaffs_allocator.h
> >
> > diff --git a/drivers/staging/yaffs2/yaffs_allocator.c
> > b/drivers/staging/yaffs2/yaffs_allocator.c new file mode 100644
> > index 0000000..024ee2a
> > --- /dev/null
> > +++ b/drivers/staging/yaffs2/yaffs_allocator.c
> > @@ -0,0 +1,408 @@
> > +/*
> > + * YAFFS: Yet Another Flash File System. A NAND-flash specific file
> > system. + *
> > + * Copyright (C) 2002-2010 Aleph One Ltd.
> > + *   for Toby Churchill Ltd and Brightstar Engineering
> > + *
> > + * Created by Charles Manning <charles@aleph1.co.uk>
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License version 2 as
> > + * published by the Free Software Foundation.
> > + */
> > +
> > +
> > +
> > +#include "yaffs_allocator.h"
> > +#include "yaffs_guts.h"
> > +#include "yaffs_trace.h"
> > +#include "yportenv.h"
> > +
> > +#ifdef CONFIG_YAFFS_YMALLOC_ALLOCATOR
> > +
> > +void yaffs_deinit_raw_tnodes_and_objs(yaffs_dev_t *dev)
> > +{
> > +       dev = dev;
> > +}
> > +
> > +void yaffs_init_raw_tnodes_and_objs(yaffs_dev_t *dev)
> > +{
> > +       dev = dev;
> > +}
> > +
> > +yaffs_tnode_t *yaffs_alloc_raw_tnode(yaffs_dev_t *dev)
> > +{
> > +       return (yaffs_tnode_t *)YMALLOC(dev->tnode_size);
> > +}
> > +
> > +void yaffs_free_raw_tnode(yaffs_dev_t *dev, yaffs_tnode_t *tn)
> > +{
> > +       dev = dev;
> > +       YFREE(tn);
> > +}
>
> So you have your own dynamic memory allocator? What's wrong with kmalloc()?

No. YMALLOC() wraps kmalloc() to keep the code portable.

This code does a home-grown slab allocator. The reason for doing this is that 
Linux slab does not allow slab caches to be destroyed while objects exist. 

While that might sound like a dangerous practice, it does mean that when yaffs 
unmounts it can drop all the data structures without having to walk all the 
trees freeing the objects.



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Re: [PATCH 05/29] Staging: yaffs2: yaffs_allocator: Add files

[Pekka Enberg]

On Mon, Nov 1, 2010 at 9:19 PM, Charles Manning <manningc2@actrix.gen.nz> wrote:
> On Tuesday 02 November 2010 07:58:49 Pekka Enberg wrote:
>> On Mon, Nov 1, 2010 at 8:40 PM, Tracey Dent <tdent48227@gmail.com> wrote:
>> > Adding files to yaffs2 directory.
>> >
>> > Signed-off-by: Tracey Dent <tdent48227@gmail.com>
>> > ---
>> >  drivers/staging/yaffs2/yaffs_allocator.c |  408
>> > ++++++++++++++++++++++++++++++ drivers/staging/yaffs2/yaffs_allocator.h |
>> >   30 +++
>> >  2 files changed, 438 insertions(+), 0 deletions(-)
>> >  create mode 100644 drivers/staging/yaffs2/yaffs_allocator.c
>> >  create mode 100644 drivers/staging/yaffs2/yaffs_allocator.h
>> >
>> > diff --git a/drivers/staging/yaffs2/yaffs_allocator.c
>> > b/drivers/staging/yaffs2/yaffs_allocator.c new file mode 100644
>> > index 0000000..024ee2a
>> > --- /dev/null
>> > +++ b/drivers/staging/yaffs2/yaffs_allocator.c
>> > @@ -0,0 +1,408 @@
>> > +/*
>> > + * YAFFS: Yet Another Flash File System. A NAND-flash specific file
>> > system. + *
>> > + * Copyright (C) 2002-2010 Aleph One Ltd.
>> > + *   for Toby Churchill Ltd and Brightstar Engineering
>> > + *
>> > + * Created by Charles Manning <charles@aleph1.co.uk>
>> > + *
>> > + * This program is free software; you can redistribute it and/or modify
>> > + * it under the terms of the GNU General Public License version 2 as
>> > + * published by the Free Software Foundation.
>> > + */
>> > +
>> > +
>> > +
>> > +#include "yaffs_allocator.h"
>> > +#include "yaffs_guts.h"
>> > +#include "yaffs_trace.h"
>> > +#include "yportenv.h"
>> > +
>> > +#ifdef CONFIG_YAFFS_YMALLOC_ALLOCATOR
>> > +
>> > +void yaffs_deinit_raw_tnodes_and_objs(yaffs_dev_t *dev)
>> > +{
>> > +       dev = dev;
>> > +}
>> > +
>> > +void yaffs_init_raw_tnodes_and_objs(yaffs_dev_t *dev)
>> > +{
>> > +       dev = dev;
>> > +}
>> > +
>> > +yaffs_tnode_t *yaffs_alloc_raw_tnode(yaffs_dev_t *dev)
>> > +{
>> > +       return (yaffs_tnode_t *)YMALLOC(dev->tnode_size);
>> > +}
>> > +
>> > +void yaffs_free_raw_tnode(yaffs_dev_t *dev, yaffs_tnode_t *tn)
>> > +{
>> > +       dev = dev;
>> > +       YFREE(tn);
>> > +}
>>
>> So you have your own dynamic memory allocator? What's wrong with kmalloc()?
>
> No. YMALLOC() wraps kmalloc() to keep the code portable.
>
> This code does a home-grown slab allocator. The reason for doing this is that
> Linux slab does not allow slab caches to be destroyed while objects exist.
>
> While that might sound like a dangerous practice, it does mean that when yaffs
> unmounts it can drop all the data structures without having to walk all the
> trees freeing the objects.

Either way, your home-grown slab allocator is not going to be merged
this way. You should be using kmem_cache_alloc() and propose proper
patches on top of mm/sl?b.c.

Re: [PATCH 05/29] Staging: yaffs2: yaffs_allocator: Add files

[Pekka Enberg]

On Mon, Nov 1, 2010 at 9:23 PM, Pekka Enberg <penberg@kernel.org> wrote:
> On Mon, Nov 1, 2010 at 9:19 PM, Charles Manning <manningc2@actrix.gen.nz> wrote:
>> On Tuesday 02 November 2010 07:58:49 Pekka Enberg wrote:
>>> On Mon, Nov 1, 2010 at 8:40 PM, Tracey Dent <tdent48227@gmail.com> wrote:
>>> > Adding files to yaffs2 directory.
>>> >
>>> > Signed-off-by: Tracey Dent <tdent48227@gmail.com>
>>> > ---
>>> >  drivers/staging/yaffs2/yaffs_allocator.c |  408
>>> > ++++++++++++++++++++++++++++++ drivers/staging/yaffs2/yaffs_allocator.h |
>>> >   30 +++
>>> >  2 files changed, 438 insertions(+), 0 deletions(-)
>>> >  create mode 100644 drivers/staging/yaffs2/yaffs_allocator.c
>>> >  create mode 100644 drivers/staging/yaffs2/yaffs_allocator.h
>>> >
>>> > diff --git a/drivers/staging/yaffs2/yaffs_allocator.c
>>> > b/drivers/staging/yaffs2/yaffs_allocator.c new file mode 100644
>>> > index 0000000..024ee2a
>>> > --- /dev/null
>>> > +++ b/drivers/staging/yaffs2/yaffs_allocator.c
>>> > @@ -0,0 +1,408 @@
>>> > +/*
>>> > + * YAFFS: Yet Another Flash File System. A NAND-flash specific file
>>> > system. + *
>>> > + * Copyright (C) 2002-2010 Aleph One Ltd.
>>> > + *   for Toby Churchill Ltd and Brightstar Engineering
>>> > + *
>>> > + * Created by Charles Manning <charles@aleph1.co.uk>
>>> > + *
>>> > + * This program is free software; you can redistribute it and/or modify
>>> > + * it under the terms of the GNU General Public License version 2 as
>>> > + * published by the Free Software Foundation.
>>> > + */
>>> > +
>>> > +
>>> > +
>>> > +#include "yaffs_allocator.h"
>>> > +#include "yaffs_guts.h"
>>> > +#include "yaffs_trace.h"
>>> > +#include "yportenv.h"
>>> > +
>>> > +#ifdef CONFIG_YAFFS_YMALLOC_ALLOCATOR
>>> > +
>>> > +void yaffs_deinit_raw_tnodes_and_objs(yaffs_dev_t *dev)
>>> > +{
>>> > +       dev = dev;
>>> > +}
>>> > +
>>> > +void yaffs_init_raw_tnodes_and_objs(yaffs_dev_t *dev)
>>> > +{
>>> > +       dev = dev;
>>> > +}
>>> > +
>>> > +yaffs_tnode_t *yaffs_alloc_raw_tnode(yaffs_dev_t *dev)
>>> > +{
>>> > +       return (yaffs_tnode_t *)YMALLOC(dev->tnode_size);
>>> > +}
>>> > +
>>> > +void yaffs_free_raw_tnode(yaffs_dev_t *dev, yaffs_tnode_t *tn)
>>> > +{
>>> > +       dev = dev;
>>> > +       YFREE(tn);
>>> > +}
>>>
>>> So you have your own dynamic memory allocator? What's wrong with kmalloc()?
>>
>> No. YMALLOC() wraps kmalloc() to keep the code portable.
>>
>> This code does a home-grown slab allocator. The reason for doing this is that
>> Linux slab does not allow slab caches to be destroyed while objects exist.
>>
>> While that might sound like a dangerous practice, it does mean that when yaffs
>> unmounts it can drop all the data structures without having to walk all the
>> trees freeing the objects.
>
> Either way, your home-grown slab allocator is not going to be merged
> this way. You should be using kmem_cache_alloc() and propose proper
> patches on top of mm/sl?b.c.

Btw, just to clarify: Greg might not mind taking it in as-is but it'll
never be promoted to mainline proper this way.
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[PATCH 06/29] Staging: yaffs2: yaffs_bitmap: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_bitmap.c |  105 +++++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_bitmap.h |   33 ++++++++++
 2 files changed, 138 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_bitmap.c
 create mode 100644 drivers/staging/yaffs2/yaffs_bitmap.h

diff --git a/drivers/staging/yaffs2/yaffs_bitmap.c b/drivers/staging/yaffs2/yaffs_bitmap.c
new file mode 100644
index 0000000..85c8c1d
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_bitmap.c
@@ -0,0 +1,105 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_bitmap.h"
+#include "yaffs_trace.h"
+/*
+ * Chunk bitmap manipulations
+ */
+
+static Y_INLINE __u8 *yaffs_block_bits(yaffs_dev_t *dev, int blk)
+{
+	if (blk < dev->internal_start_block || blk > dev->internal_end_block) {
+		T(YAFFS_TRACE_ERROR,
+			(TSTR("**>> yaffs: BlockBits block %d is not valid" TENDSTR),
+			blk));
+		YBUG();
+	}
+	return dev->chunk_bits +
+		(dev->chunk_bit_stride * (blk - dev->internal_start_block));
+}
+
+void yaffs_verify_chunk_bit_id(yaffs_dev_t *dev, int blk, int chunk)
+{
+	if (blk < dev->internal_start_block || blk > dev->internal_end_block ||
+			chunk < 0 || chunk >= dev->param.chunks_per_block) {
+		T(YAFFS_TRACE_ERROR,
+		(TSTR("**>> yaffs: Chunk Id (%d:%d) invalid"TENDSTR),
+			blk, chunk));
+		YBUG();
+	}
+}
+
+void yaffs_clear_chunk_bits(yaffs_dev_t *dev, int blk)
+{
+	__u8 *blk_bits = yaffs_block_bits(dev, blk);
+
+	memset(blk_bits, 0, dev->chunk_bit_stride);
+}
+
+void yaffs_clear_chunk_bit(yaffs_dev_t *dev, int blk, int chunk)
+{
+	__u8 *blk_bits = yaffs_block_bits(dev, blk);
+
+	yaffs_verify_chunk_bit_id(dev, blk, chunk);
+
+	blk_bits[chunk / 8] &= ~(1 << (chunk & 7));
+}
+
+void yaffs_set_chunk_bit(yaffs_dev_t *dev, int blk, int chunk)
+{
+	__u8 *blk_bits = yaffs_block_bits(dev, blk);
+
+	yaffs_verify_chunk_bit_id(dev, blk, chunk);
+
+	blk_bits[chunk / 8] |= (1 << (chunk & 7));
+}
+
+int yaffs_check_chunk_bit(yaffs_dev_t *dev, int blk, int chunk)
+{
+	__u8 *blk_bits = yaffs_block_bits(dev, blk);
+	yaffs_verify_chunk_bit_id(dev, blk, chunk);
+
+	return (blk_bits[chunk / 8] & (1 << (chunk & 7))) ? 1 : 0;
+}
+
+int yaffs_still_some_chunks(yaffs_dev_t *dev, int blk)
+{
+	__u8 *blk_bits = yaffs_block_bits(dev, blk);
+	int i;
+	for (i = 0; i < dev->chunk_bit_stride; i++) {
+		if (*blk_bits)
+			return 1;
+		blk_bits++;
+	}
+	return 0;
+}
+
+int yaffs_count_chunk_bits(yaffs_dev_t *dev, int blk)
+{
+	__u8 *blk_bits = yaffs_block_bits(dev, blk);
+	int i;
+	int n = 0;
+	for (i = 0; i < dev->chunk_bit_stride; i++) {
+		__u8 x = *blk_bits;
+		while (x) {
+			if (x & 1)
+				n++;
+			x >>= 1;
+		}
+
+		blk_bits++;
+	}
+	return n;
+}
+
diff --git a/drivers/staging/yaffs2/yaffs_bitmap.h b/drivers/staging/yaffs2/yaffs_bitmap.h
new file mode 100644
index 0000000..ea755be
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_bitmap.h
@@ -0,0 +1,33 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+/*
+ * Chunk bitmap manipulations
+ */
+
+#ifndef __YAFFS_BITMAP_H__
+#define __YAFFS_BITMAP_H__
+
+#include "yaffs_guts.h"
+
+void yaffs_verify_chunk_bit_id(yaffs_dev_t *dev, int blk, int chunk);
+void yaffs_clear_chunk_bits(yaffs_dev_t *dev, int blk);
+void yaffs_clear_chunk_bit(yaffs_dev_t *dev, int blk, int chunk);
+void yaffs_set_chunk_bit(yaffs_dev_t *dev, int blk, int chunk);
+int yaffs_check_chunk_bit(yaffs_dev_t *dev, int blk, int chunk);
+int yaffs_still_some_chunks(yaffs_dev_t *dev, int blk);
+int yaffs_count_chunk_bits(yaffs_dev_t *dev, int blk);
+
+#endif
-- 
1.7.3.2.146.gca209

Re: [PATCH 06/29] Staging: yaffs2: yaffs_bitmap: Add files

[Pekka Enberg]

On Mon, Nov 1, 2010 at 8:40 PM, Tracey Dent <tdent48227@gmail.com> wrote:
> Adding files to yaffs2 directory.
>
> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> ---
>  drivers/staging/yaffs2/yaffs_bitmap.c |  105 +++++++++++++++++++++++++++++++++
>  drivers/staging/yaffs2/yaffs_bitmap.h |   33 ++++++++++
>  2 files changed, 138 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/yaffs2/yaffs_bitmap.c
>  create mode 100644 drivers/staging/yaffs2/yaffs_bitmap.h
>
> diff --git a/drivers/staging/yaffs2/yaffs_bitmap.c b/drivers/staging/yaffs2/yaffs_bitmap.c
> new file mode 100644
> index 0000000..85c8c1d
> --- /dev/null
> +++ b/drivers/staging/yaffs2/yaffs_bitmap.c
> @@ -0,0 +1,105 @@
> +/*
> + * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
> + *
> + * Copyright (C) 2002-2010 Aleph One Ltd.
> + *   for Toby Churchill Ltd and Brightstar Engineering
> + *
> + * Created by Charles Manning <charles@aleph1.co.uk>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include "yaffs_bitmap.h"
> +#include "yaffs_trace.h"
> +/*
> + * Chunk bitmap manipulations
> + */
> +
> +static Y_INLINE __u8 *yaffs_block_bits(yaffs_dev_t *dev, int blk)
> +{
> +       if (blk < dev->internal_start_block || blk > dev->internal_end_block) {
> +               T(YAFFS_TRACE_ERROR,
> +                       (TSTR("**>> yaffs: BlockBits block %d is not valid" TENDSTR),
> +                       blk));
> +               YBUG();
> +       }
> +       return dev->chunk_bits +
> +               (dev->chunk_bit_stride * (blk - dev->internal_start_block));
> +}

We have <linux/bitmap.h>. You should probably use it.
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[PATCH 07/29] Staging: yaffs2: yaffs_checkptrw: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_checkptrw.c |  400 ++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_checkptrw.h |   34 +++
 2 files changed, 434 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_checkptrw.c
 create mode 100644 drivers/staging/yaffs2/yaffs_checkptrw.h

diff --git a/drivers/staging/yaffs2/yaffs_checkptrw.c b/drivers/staging/yaffs2/yaffs_checkptrw.c
new file mode 100644
index 0000000..82d6874
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_checkptrw.c
@@ -0,0 +1,400 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_checkptrw.h"
+#include "yaffs_getblockinfo.h"
+
+static int yaffs2_checkpt_space_ok(yaffs_dev_t *dev)
+{
+	int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
+
+	T(YAFFS_TRACE_CHECKPOINT,
+		(TSTR("checkpt blocks available = %d" TENDSTR),
+		blocks_avail));
+
+	return (blocks_avail <= 0) ? 0 : 1;
+}
+
+
+static int yaffs_checkpt_erase(yaffs_dev_t *dev)
+{
+	int i;
+
+	if (!dev->param.erase_fn)
+		return 0;
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("checking blocks %d to %d"TENDSTR),
+		dev->internal_start_block, dev->internal_end_block));
+
+	for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
+		yaffs_block_info_t *bi = yaffs_get_block_info(dev, i);
+		if (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT) {
+			T(YAFFS_TRACE_CHECKPOINT, (TSTR("erasing checkpt block %d"TENDSTR), i));
+
+			dev->n_erasures++;
+
+			if (dev->param.erase_fn(dev, i - dev->block_offset /* realign */)) {
+				bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
+				dev->n_erased_blocks++;
+				dev->n_free_chunks += dev->param.chunks_per_block;
+			} else {
+				dev->param.bad_block_fn(dev, i);
+				bi->block_state = YAFFS_BLOCK_STATE_DEAD;
+			}
+		}
+	}
+
+	dev->blocks_in_checkpt = 0;
+
+	return 1;
+}
+
+
+static void yaffs2_checkpt_find_erased_block(yaffs_dev_t *dev)
+{
+	int  i;
+	int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
+	T(YAFFS_TRACE_CHECKPOINT,
+		(TSTR("allocating checkpt block: erased %d reserved %d avail %d next %d "TENDSTR),
+		dev->n_erased_blocks, dev->param.n_reserved_blocks, blocks_avail, dev->checkpt_next_block));
+
+	if (dev->checkpt_next_block >= 0 &&
+			dev->checkpt_next_block <= dev->internal_end_block &&
+			blocks_avail > 0) {
+
+		for (i = dev->checkpt_next_block; i <= dev->internal_end_block; i++) {
+			yaffs_block_info_t *bi = yaffs_get_block_info(dev, i);
+			if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
+				dev->checkpt_next_block = i + 1;
+				dev->checkpt_cur_block = i;
+				T(YAFFS_TRACE_CHECKPOINT, (TSTR("allocating checkpt block %d"TENDSTR), i));
+				return;
+			}
+		}
+	}
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("out of checkpt blocks"TENDSTR)));
+
+	dev->checkpt_next_block = -1;
+	dev->checkpt_cur_block = -1;
+}
+
+static void yaffs2_checkpt_find_block(yaffs_dev_t *dev)
+{
+	int  i;
+	yaffs_ext_tags tags;
+
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("find next checkpt block: start:  blocks %d next %d" TENDSTR),
+		dev->blocks_in_checkpt, dev->checkpt_next_block));
+
+	if (dev->blocks_in_checkpt < dev->checkpt_max_blocks)
+		for (i = dev->checkpt_next_block; i <= dev->internal_end_block; i++) {
+			int chunk = i * dev->param.chunks_per_block;
+			int realigned_chunk = chunk - dev->chunk_offset;
+
+			dev->param.read_chunk_tags_fn(dev, realigned_chunk,
+					NULL, &tags);
+			T(YAFFS_TRACE_CHECKPOINT, (TSTR("find next checkpt block: search: block %d oid %d seq %d eccr %d" TENDSTR),
+				i, tags.obj_id, tags.seq_number, tags.ecc_result));
+
+			if (tags.seq_number == YAFFS_SEQUENCE_CHECKPOINT_DATA) {
+				/* Right kind of block */
+				dev->checkpt_next_block = tags.obj_id;
+				dev->checkpt_cur_block = i;
+				dev->checkpt_block_list[dev->blocks_in_checkpt] = i;
+				dev->blocks_in_checkpt++;
+				T(YAFFS_TRACE_CHECKPOINT, (TSTR("found checkpt block %d"TENDSTR), i));
+				return;
+			}
+		}
+
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("found no more checkpt blocks"TENDSTR)));
+
+	dev->checkpt_next_block = -1;
+	dev->checkpt_cur_block = -1;
+}
+
+
+int yaffs2_checkpt_open(yaffs_dev_t *dev, int writing)
+{
+
+
+	dev->checkpt_open_write = writing;
+
+	/* Got the functions we need? */
+	if (!dev->param.write_chunk_tags_fn ||
+		!dev->param.read_chunk_tags_fn ||
+		!dev->param.erase_fn ||
+		!dev->param.bad_block_fn)
+		return 0;
+
+	if (writing && !yaffs2_checkpt_space_ok(dev))
+		return 0;
+
+	if (!dev->checkpt_buffer)
+		dev->checkpt_buffer = YMALLOC_DMA(dev->param.total_bytes_per_chunk);
+	if (!dev->checkpt_buffer)
+		return 0;
+
+
+	dev->checkpt_page_seq = 0;
+	dev->checkpt_byte_count = 0;
+	dev->checkpt_sum = 0;
+	dev->checkpt_xor = 0;
+	dev->checkpt_cur_block = -1;
+	dev->checkpt_cur_chunk = -1;
+	dev->checkpt_next_block = dev->internal_start_block;
+
+	/* Erase all the blocks in the checkpoint area */
+	if (writing) {
+		memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
+		dev->checkpt_byte_offs = 0;
+		return yaffs_checkpt_erase(dev);
+	} else {
+		int i;
+		/* Set to a value that will kick off a read */
+		dev->checkpt_byte_offs = dev->data_bytes_per_chunk;
+		/* A checkpoint block list of 1 checkpoint block per 16 block is (hopefully)
+		 * going to be way more than we need */
+		dev->blocks_in_checkpt = 0;
+		dev->checkpt_max_blocks = (dev->internal_end_block - dev->internal_start_block)/16 + 2;
+		dev->checkpt_block_list = YMALLOC(sizeof(int) * dev->checkpt_max_blocks);
+		if(!dev->checkpt_block_list)
+			return 0;
+
+		for (i = 0; i < dev->checkpt_max_blocks; i++)
+			dev->checkpt_block_list[i] = -1;
+	}
+
+	return 1;
+}
+
+int yaffs2_get_checkpt_sum(yaffs_dev_t *dev, __u32 *sum)
+{
+	__u32 composite_sum;
+	composite_sum =  (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xFF);
+	*sum = composite_sum;
+	return 1;
+}
+
+static int yaffs2_checkpt_flush_buffer(yaffs_dev_t *dev)
+{
+	int chunk;
+	int realigned_chunk;
+
+	yaffs_ext_tags tags;
+
+	if (dev->checkpt_cur_block < 0) {
+		yaffs2_checkpt_find_erased_block(dev);
+		dev->checkpt_cur_chunk = 0;
+	}
+
+	if (dev->checkpt_cur_block < 0)
+		return 0;
+
+	tags.is_deleted = 0;
+	tags.obj_id = dev->checkpt_next_block; /* Hint to next place to look */
+	tags.chunk_id = dev->checkpt_page_seq + 1;
+	tags.seq_number =  YAFFS_SEQUENCE_CHECKPOINT_DATA;
+	tags.n_bytes = dev->data_bytes_per_chunk;
+	if (dev->checkpt_cur_chunk == 0) {
+		/* First chunk we write for the block? Set block state to
+		   checkpoint */
+		yaffs_block_info_t *bi = yaffs_get_block_info(dev, dev->checkpt_cur_block);
+		bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
+		dev->blocks_in_checkpt++;
+	}
+
+	chunk = dev->checkpt_cur_block * dev->param.chunks_per_block + dev->checkpt_cur_chunk;
+
+
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint wite buffer nand %d(%d:%d) objid %d chId %d" TENDSTR),
+		chunk, dev->checkpt_cur_block, dev->checkpt_cur_chunk, tags.obj_id, tags.chunk_id));
+
+	realigned_chunk = chunk - dev->chunk_offset;
+
+	dev->n_page_writes++;
+
+	dev->param.write_chunk_tags_fn(dev, realigned_chunk,
+			dev->checkpt_buffer, &tags);
+	dev->checkpt_byte_offs = 0;
+	dev->checkpt_page_seq++;
+	dev->checkpt_cur_chunk++;
+	if (dev->checkpt_cur_chunk >= dev->param.chunks_per_block) {
+		dev->checkpt_cur_chunk = 0;
+		dev->checkpt_cur_block = -1;
+	}
+	memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
+
+	return 1;
+}
+
+
+int yaffs2_checkpt_wr(yaffs_dev_t *dev, const void *data, int n_bytes)
+{
+	int i = 0;
+	int ok = 1;
+
+
+	__u8 * data_bytes = (__u8 *)data;
+
+
+
+	if (!dev->checkpt_buffer)
+		return 0;
+
+	if (!dev->checkpt_open_write)
+		return -1;
+
+	while (i < n_bytes && ok) {
+		dev->checkpt_buffer[dev->checkpt_byte_offs] = *data_bytes;
+		dev->checkpt_sum += *data_bytes;
+		dev->checkpt_xor ^= *data_bytes;
+
+		dev->checkpt_byte_offs++;
+		i++;
+		data_bytes++;
+		dev->checkpt_byte_count++;
+
+
+		if (dev->checkpt_byte_offs < 0 ||
+		   dev->checkpt_byte_offs >= dev->data_bytes_per_chunk)
+			ok = yaffs2_checkpt_flush_buffer(dev);
+	}
+
+	return i;
+}
+
+int yaffs2_checkpt_rd(yaffs_dev_t *dev, void *data, int n_bytes)
+{
+	int i = 0;
+	int ok = 1;
+	yaffs_ext_tags tags;
+
+
+	int chunk;
+	int realigned_chunk;
+
+	__u8 *data_bytes = (__u8 *)data;
+
+	if (!dev->checkpt_buffer)
+		return 0;
+
+	if (dev->checkpt_open_write)
+		return -1;
+
+	while (i < n_bytes && ok) {
+
+
+		if (dev->checkpt_byte_offs < 0 ||
+			dev->checkpt_byte_offs >= dev->data_bytes_per_chunk) {
+
+			if (dev->checkpt_cur_block < 0) {
+				yaffs2_checkpt_find_block(dev);
+				dev->checkpt_cur_chunk = 0;
+			}
+
+			if (dev->checkpt_cur_block < 0)
+				ok = 0;
+			else {
+				chunk = dev->checkpt_cur_block *
+					dev->param.chunks_per_block +
+					dev->checkpt_cur_chunk;
+
+				realigned_chunk = chunk - dev->chunk_offset;
+				
+				dev->n_page_reads++;
+
+				/* read in the next chunk */
+				dev->param.read_chunk_tags_fn(dev,
+						realigned_chunk,
+						dev->checkpt_buffer,
+						&tags);
+
+				if (tags.chunk_id != (dev->checkpt_page_seq + 1) ||
+					tags.ecc_result > YAFFS_ECC_RESULT_FIXED ||
+					tags.seq_number != YAFFS_SEQUENCE_CHECKPOINT_DATA)
+					ok = 0;
+
+				dev->checkpt_byte_offs = 0;
+				dev->checkpt_page_seq++;
+				dev->checkpt_cur_chunk++;
+
+				if (dev->checkpt_cur_chunk >= dev->param.chunks_per_block)
+					dev->checkpt_cur_block = -1;
+			}
+		}
+
+		if (ok) {
+			*data_bytes = dev->checkpt_buffer[dev->checkpt_byte_offs];
+			dev->checkpt_sum += *data_bytes;
+			dev->checkpt_xor ^= *data_bytes;
+			dev->checkpt_byte_offs++;
+			i++;
+			data_bytes++;
+			dev->checkpt_byte_count++;
+		}
+	}
+
+	return 	i;
+}
+
+int yaffs_checkpt_close(yaffs_dev_t *dev)
+{
+
+	if (dev->checkpt_open_write) {
+		if (dev->checkpt_byte_offs != 0)
+			yaffs2_checkpt_flush_buffer(dev);
+	} else if(dev->checkpt_block_list){
+		int i;
+		for (i = 0; i < dev->blocks_in_checkpt && dev->checkpt_block_list[i] >= 0; i++) {
+			int blk = dev->checkpt_block_list[i];
+			yaffs_block_info_t *bi = NULL;
+			if( dev->internal_start_block <= blk && blk <= dev->internal_end_block)
+				bi = yaffs_get_block_info(dev, blk);
+			if (bi && bi->block_state == YAFFS_BLOCK_STATE_EMPTY)
+				bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
+			else {
+				/* Todo this looks odd... */
+			}
+		}
+		YFREE(dev->checkpt_block_list);
+		dev->checkpt_block_list = NULL;
+	}
+
+	dev->n_free_chunks -= dev->blocks_in_checkpt * dev->param.chunks_per_block;
+	dev->n_erased_blocks -= dev->blocks_in_checkpt;
+
+
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint byte count %d" TENDSTR),
+			dev->checkpt_byte_count));
+
+	if (dev->checkpt_buffer) {
+		/* free the buffer */
+		YFREE(dev->checkpt_buffer);
+		dev->checkpt_buffer = NULL;
+		return 1;
+	} else
+		return 0;
+}
+
+int yaffs2_checkpt_invalidate_stream(yaffs_dev_t *dev)
+{
+	/* Erase the checkpoint data */
+
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint invalidate of %d blocks"TENDSTR),
+		dev->blocks_in_checkpt));
+
+	return yaffs_checkpt_erase(dev);
+}
+
+
+
diff --git a/drivers/staging/yaffs2/yaffs_checkptrw.h b/drivers/staging/yaffs2/yaffs_checkptrw.h
new file mode 100644
index 0000000..582b89c
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_checkptrw.h
@@ -0,0 +1,34 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_CHECKPTRW_H__
+#define __YAFFS_CHECKPTRW_H__
+
+#include "yaffs_guts.h"
+
+int yaffs2_checkpt_open(yaffs_dev_t *dev, int writing);
+
+int yaffs2_checkpt_wr(yaffs_dev_t *dev, const void *data, int n_bytes);
+
+int yaffs2_checkpt_rd(yaffs_dev_t *dev, void *data, int n_bytes);
+
+int yaffs2_get_checkpt_sum(yaffs_dev_t *dev, __u32 *sum);
+
+int yaffs_checkpt_close(yaffs_dev_t *dev);
+
+int yaffs2_checkpt_invalidate_stream(yaffs_dev_t *dev);
+
+
+#endif
-- 
1.7.3.2.146.gca209

Re: [PATCH 07/29] Staging: yaffs2: yaffs_checkptrw: Add files

[Jesper Juhl]

On Mon, 1 Nov 2010, Tracey Dent wrote:

> Adding files to yaffs2 directory.
> 
> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> ---
>  drivers/staging/yaffs2/yaffs_checkptrw.c |  400 ++++++++++++++++++++++++++++++
>  drivers/staging/yaffs2/yaffs_checkptrw.h |   34 +++
>  2 files changed, 434 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/yaffs2/yaffs_checkptrw.c
>  create mode 100644 drivers/staging/yaffs2/yaffs_checkptrw.h
> 
> diff --git a/drivers/staging/yaffs2/yaffs_checkptrw.c b/drivers/staging/yaffs2/yaffs_checkptrw.c
> new file mode 100644
> index 0000000..82d6874
> --- /dev/null
> +++ b/drivers/staging/yaffs2/yaffs_checkptrw.c
[snip]
> +static void yaffs2_checkpt_find_erased_block(yaffs_dev_t *dev)
> +{
> +	int  i;
> +	int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
> +	T(YAFFS_TRACE_CHECKPOINT,
> +		(TSTR("allocating checkpt block: erased %d reserved %d avail %d next %d "TENDSTR),
> +		dev->n_erased_blocks, dev->param.n_reserved_blocks, blocks_avail, dev->checkpt_next_block));
> +
> +	if (dev->checkpt_next_block >= 0 &&
> +			dev->checkpt_next_block <= dev->internal_end_block &&
> +			blocks_avail > 0) {
> +

Ok, perhaps I've been writing C++ apps in userspace too much, but on first 
impulse I'd say that the 'i' variable should be declared here in this 
scope where it's first used and not in global function scope.

> +		for (i = dev->checkpt_next_block; i <= dev->internal_end_block; i++) {

[snip]
> +static void yaffs2_checkpt_find_block(yaffs_dev_t *dev)
> +{
> +	int  i;
> +	yaffs_ext_tags tags;
> +
> +	T(YAFFS_TRACE_CHECKPOINT, (TSTR("find next checkpt block: start:  blocks %d next %d" TENDSTR),
> +		dev->blocks_in_checkpt, dev->checkpt_next_block));
> +
> +	if (dev->blocks_in_checkpt < dev->checkpt_max_blocks)

same here.

> +		for (i = dev->checkpt_next_block; i <= dev->internal_end_block; i++) {


[snip]
> +int yaffs2_checkpt_open(yaffs_dev_t *dev, int writing)
> +{
> +
> +

Small thing, but I've seen this a lot in these patches - double blank 
lines (or more) where either a single one or zero would do just as well 
(or actually better).

It's a small thing, but the number of (relevant) code lines visible on the 
screen at once actually matters. Sure, a blank line between blocks often 
makes sense in order to visually seperate one block of code from another, 
but two (or more) lines often don't serve a purpose except prevent more 
relevant stuff to being visible - especially in cases like this where it's 
at the start of a function, I really don't see the point.


> +int yaffs2_get_checkpt_sum(yaffs_dev_t *dev, __u32 *sum)
> +{
> +	__u32 composite_sum;
> +	composite_sum =  (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xFF);
> +	*sum = composite_sum;
> +	return 1;
> +}

Why not

int yaffs2_get_checkpt_sum(yaffs_dev_t *dev, __u32 *sum)
{
     *sum  = (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xFF);
     return 1;
}

???


-- 
Jesper Juhl <jj@chaosbits.net>             http://www.chaosbits.net/
Plain text mails only, please      http://www.expita.com/nomime.html
Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html

Re: [PATCH 07/29] Staging: yaffs2: yaffs_checkptrw: Add files

[Jesper Juhl]

On Mon, 1 Nov 2010, Jesper Juhl wrote:

> On Mon, 1 Nov 2010, Tracey Dent wrote:
> 
[snip]
> 
> > +int yaffs2_get_checkpt_sum(yaffs_dev_t *dev, __u32 *sum)
> > +{
> > +	__u32 composite_sum;
> > +	composite_sum =  (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xFF);
> > +	*sum = composite_sum;
> > +	return 1;
> > +}
> 
> Why not
> 
> int yaffs2_get_checkpt_sum(yaffs_dev_t *dev, __u32 *sum)
> {
>      *sum  = (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xFF);
>      return 1;
> }
> 

And by the way, why is this function not returning 'void' so it just 
becomes:

void yaffs2_get_checkpt_sum(yaffs_dev_t *dev, __u32 *sum)
{
     *sum  = (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xFF);
}

Since it's always returning '1' I fail to see the point of the 'int' 
return value.

-- 
Jesper Juhl <jj@chaosbits.net>             http://www.chaosbits.net/
Plain text mails only, please      http://www.expita.com/nomime.html
Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html

[PATCH 08/29] Staging: yaffs2: yaffs_ecc: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_ecc.c |  323 ++++++++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_ecc.h |   44 +++++
 2 files changed, 367 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_ecc.c
 create mode 100644 drivers/staging/yaffs2/yaffs_ecc.h

diff --git a/drivers/staging/yaffs2/yaffs_ecc.c b/drivers/staging/yaffs2/yaffs_ecc.c
new file mode 100644
index 0000000..35f8747
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_ecc.c
@@ -0,0 +1,323 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/*
+ * This code implements the ECC algorithm used in SmartMedia.
+ *
+ * The ECC comprises 22 bits of parity information and is stuffed into 3 bytes.
+ * The two unused bit are set to 1.
+ * The ECC can correct single bit errors in a 256-byte page of data. Thus, two such ECC
+ * blocks are used on a 512-byte NAND page.
+ *
+ */
+
+/* Table generated by gen-ecc.c
+ * Using a table means we do not have to calculate p1..p4 and p1'..p4'
+ * for each byte of data. These are instead provided in a table in bits7..2.
+ * Bit 0 of each entry indicates whether the entry has an odd or even parity, and therefore
+ * this bytes influence on the line parity.
+ */
+
+#include "yportenv.h"
+
+#include "yaffs_ecc.h"
+
+static const unsigned char column_parity_table[] = {
+	0x00, 0x55, 0x59, 0x0c, 0x65, 0x30, 0x3c, 0x69,
+	0x69, 0x3c, 0x30, 0x65, 0x0c, 0x59, 0x55, 0x00,
+	0x95, 0xc0, 0xcc, 0x99, 0xf0, 0xa5, 0xa9, 0xfc,
+	0xfc, 0xa9, 0xa5, 0xf0, 0x99, 0xcc, 0xc0, 0x95,
+	0x99, 0xcc, 0xc0, 0x95, 0xfc, 0xa9, 0xa5, 0xf0,
+	0xf0, 0xa5, 0xa9, 0xfc, 0x95, 0xc0, 0xcc, 0x99,
+	0x0c, 0x59, 0x55, 0x00, 0x69, 0x3c, 0x30, 0x65,
+	0x65, 0x30, 0x3c, 0x69, 0x00, 0x55, 0x59, 0x0c,
+	0xa5, 0xf0, 0xfc, 0xa9, 0xc0, 0x95, 0x99, 0xcc,
+	0xcc, 0x99, 0x95, 0xc0, 0xa9, 0xfc, 0xf0, 0xa5,
+	0x30, 0x65, 0x69, 0x3c, 0x55, 0x00, 0x0c, 0x59,
+	0x59, 0x0c, 0x00, 0x55, 0x3c, 0x69, 0x65, 0x30,
+	0x3c, 0x69, 0x65, 0x30, 0x59, 0x0c, 0x00, 0x55,
+	0x55, 0x00, 0x0c, 0x59, 0x30, 0x65, 0x69, 0x3c,
+	0xa9, 0xfc, 0xf0, 0xa5, 0xcc, 0x99, 0x95, 0xc0,
+	0xc0, 0x95, 0x99, 0xcc, 0xa5, 0xf0, 0xfc, 0xa9,
+	0xa9, 0xfc, 0xf0, 0xa5, 0xcc, 0x99, 0x95, 0xc0,
+	0xc0, 0x95, 0x99, 0xcc, 0xa5, 0xf0, 0xfc, 0xa9,
+	0x3c, 0x69, 0x65, 0x30, 0x59, 0x0c, 0x00, 0x55,
+	0x55, 0x00, 0x0c, 0x59, 0x30, 0x65, 0x69, 0x3c,
+	0x30, 0x65, 0x69, 0x3c, 0x55, 0x00, 0x0c, 0x59,
+	0x59, 0x0c, 0x00, 0x55, 0x3c, 0x69, 0x65, 0x30,
+	0xa5, 0xf0, 0xfc, 0xa9, 0xc0, 0x95, 0x99, 0xcc,
+	0xcc, 0x99, 0x95, 0xc0, 0xa9, 0xfc, 0xf0, 0xa5,
+	0x0c, 0x59, 0x55, 0x00, 0x69, 0x3c, 0x30, 0x65,
+	0x65, 0x30, 0x3c, 0x69, 0x00, 0x55, 0x59, 0x0c,
+	0x99, 0xcc, 0xc0, 0x95, 0xfc, 0xa9, 0xa5, 0xf0,
+	0xf0, 0xa5, 0xa9, 0xfc, 0x95, 0xc0, 0xcc, 0x99,
+	0x95, 0xc0, 0xcc, 0x99, 0xf0, 0xa5, 0xa9, 0xfc,
+	0xfc, 0xa9, 0xa5, 0xf0, 0x99, 0xcc, 0xc0, 0x95,
+	0x00, 0x55, 0x59, 0x0c, 0x65, 0x30, 0x3c, 0x69,
+	0x69, 0x3c, 0x30, 0x65, 0x0c, 0x59, 0x55, 0x00,
+};
+
+/* Count the bits in an unsigned char or a U32 */
+
+static int yaffs_count_bits(unsigned char x)
+{
+	int r = 0;
+	while (x) {
+		if (x & 1)
+			r++;
+		x >>= 1;
+	}
+	return r;
+}
+
+static int yaffs_count_bits32(unsigned x)
+{
+	int r = 0;
+	while (x) {
+		if (x & 1)
+			r++;
+		x >>= 1;
+	}
+	return r;
+}
+
+/* Calculate the ECC for a 256-byte block of data */
+void yaffs_ecc_cacl(const unsigned char *data, unsigned char *ecc)
+{
+	unsigned int i;
+
+	unsigned char col_parity = 0;
+	unsigned char line_parity = 0;
+	unsigned char line_parity_prime = 0;
+	unsigned char t;
+	unsigned char b;
+
+	for (i = 0; i < 256; i++) {
+		b = column_parity_table[*data++];
+		col_parity ^= b;
+
+		if (b & 0x01) {		/* odd number of bits in the byte */
+			line_parity ^= i;
+			line_parity_prime ^= ~i;
+		}
+	}
+
+	ecc[2] = (~col_parity) | 0x03;
+
+	t = 0;
+	if (line_parity & 0x80)
+		t |= 0x80;
+	if (line_parity_prime & 0x80)
+		t |= 0x40;
+	if (line_parity & 0x40)
+		t |= 0x20;
+	if (line_parity_prime & 0x40)
+		t |= 0x10;
+	if (line_parity & 0x20)
+		t |= 0x08;
+	if (line_parity_prime & 0x20)
+		t |= 0x04;
+	if (line_parity & 0x10)
+		t |= 0x02;
+	if (line_parity_prime & 0x10)
+		t |= 0x01;
+	ecc[1] = ~t;
+
+	t = 0;
+	if (line_parity & 0x08)
+		t |= 0x80;
+	if (line_parity_prime & 0x08)
+		t |= 0x40;
+	if (line_parity & 0x04)
+		t |= 0x20;
+	if (line_parity_prime & 0x04)
+		t |= 0x10;
+	if (line_parity & 0x02)
+		t |= 0x08;
+	if (line_parity_prime & 0x02)
+		t |= 0x04;
+	if (line_parity & 0x01)
+		t |= 0x02;
+	if (line_parity_prime & 0x01)
+		t |= 0x01;
+	ecc[0] = ~t;
+
+#ifdef CONFIG_YAFFS_ECC_WRONG_ORDER
+	/* Swap the bytes into the wrong order */
+	t = ecc[0];
+	ecc[0] = ecc[1];
+	ecc[1] = t;
+#endif
+}
+
+
+/* Correct the ECC on a 256 byte block of data */
+
+int yaffs_ecc_correct(unsigned char *data, unsigned char *read_ecc,
+		     const unsigned char *test_ecc)
+{
+	unsigned char d0, d1, d2;	/* deltas */
+
+	d0 = read_ecc[0] ^ test_ecc[0];
+	d1 = read_ecc[1] ^ test_ecc[1];
+	d2 = read_ecc[2] ^ test_ecc[2];
+
+	if ((d0 | d1 | d2) == 0)
+		return 0; /* no error */
+
+	if (((d0 ^ (d0 >> 1)) & 0x55) == 0x55 &&
+	    ((d1 ^ (d1 >> 1)) & 0x55) == 0x55 &&
+	    ((d2 ^ (d2 >> 1)) & 0x54) == 0x54) {
+		/* Single bit (recoverable) error in data */
+
+		unsigned byte;
+		unsigned bit;
+
+#ifdef CONFIG_YAFFS_ECC_WRONG_ORDER
+		/* swap the bytes to correct for the wrong order */
+		unsigned char t;
+
+		t = d0;
+		d0 = d1;
+		d1 = t;
+#endif
+
+		bit = byte = 0;
+
+		if (d1 & 0x80)
+			byte |= 0x80;
+		if (d1 & 0x20)
+			byte |= 0x40;
+		if (d1 & 0x08)
+			byte |= 0x20;
+		if (d1 & 0x02)
+			byte |= 0x10;
+		if (d0 & 0x80)
+			byte |= 0x08;
+		if (d0 & 0x20)
+			byte |= 0x04;
+		if (d0 & 0x08)
+			byte |= 0x02;
+		if (d0 & 0x02)
+			byte |= 0x01;
+
+		if (d2 & 0x80)
+			bit |= 0x04;
+		if (d2 & 0x20)
+			bit |= 0x02;
+		if (d2 & 0x08)
+			bit |= 0x01;
+
+		data[byte] ^= (1 << bit);
+
+		return 1; /* Corrected the error */
+	}
+
+	if ((yaffs_count_bits(d0) +
+	     yaffs_count_bits(d1) +
+	     yaffs_count_bits(d2)) ==  1) {
+		/* Reccoverable error in ecc */
+
+		read_ecc[0] = test_ecc[0];
+		read_ecc[1] = test_ecc[1];
+		read_ecc[2] = test_ecc[2];
+
+		return 1; /* Corrected the error */
+	}
+
+	/* Unrecoverable error */
+
+	return -1;
+
+}
+
+
+/*
+ * ECCxxxOther does ECC calcs on arbitrary n bytes of data
+ */
+void yaffs_ecc_calc_other(const unsigned char *data, unsigned n_bytes,
+				yaffs_ecc_other *ecc_other)
+{
+	unsigned int i;
+
+	unsigned char col_parity = 0;
+	unsigned line_parity = 0;
+	unsigned line_parity_prime = 0;
+	unsigned char b;
+
+	for (i = 0; i < n_bytes; i++) {
+		b = column_parity_table[*data++];
+		col_parity ^= b;
+
+		if (b & 0x01)	 {
+			/* odd number of bits in the byte */
+			line_parity ^= i;
+			line_parity_prime ^= ~i;
+		}
+
+	}
+
+	ecc_other->col_parity = (col_parity >> 2) & 0x3f;
+	ecc_other->line_parity = line_parity;
+	ecc_other->line_parity_prime = line_parity_prime;
+}
+
+int yaffs_ecc_correct_other(unsigned char *data, unsigned n_bytes,
+			yaffs_ecc_other *read_ecc,
+			const yaffs_ecc_other *test_ecc)
+{
+	unsigned char delta_col;	/* column parity delta */
+	unsigned delta_line;	/* line parity delta */
+	unsigned delta_line_prime;	/* line parity delta */
+	unsigned bit;
+
+	delta_col = read_ecc->col_parity ^ test_ecc->col_parity;
+	delta_line = read_ecc->line_parity ^ test_ecc->line_parity;
+	delta_line_prime = read_ecc->line_parity_prime ^ test_ecc->line_parity_prime;
+
+	if ((delta_col | delta_line | delta_line_prime) == 0)
+		return 0; /* no error */
+
+	if (delta_line == ~delta_line_prime &&
+	    (((delta_col ^ (delta_col >> 1)) & 0x15) == 0x15)) {
+		/* Single bit (recoverable) error in data */
+
+		bit = 0;
+
+		if (delta_col & 0x20)
+			bit |= 0x04;
+		if (delta_col & 0x08)
+			bit |= 0x02;
+		if (delta_col & 0x02)
+			bit |= 0x01;
+
+		if (delta_line >= n_bytes)
+			return -1;
+
+		data[delta_line] ^= (1 << bit);
+
+		return 1; /* corrected */
+	}
+
+	if ((yaffs_count_bits32(delta_line) + yaffs_count_bits32(delta_line_prime) +
+			yaffs_count_bits(delta_col)) == 1) {
+		/* Reccoverable error in ecc */
+
+		*read_ecc = *test_ecc;
+		return 1; /* corrected */
+	}
+
+	/* Unrecoverable error */
+
+	return -1;
+}
diff --git a/drivers/staging/yaffs2/yaffs_ecc.h b/drivers/staging/yaffs2/yaffs_ecc.h
new file mode 100644
index 0000000..f505ab5
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_ecc.h
@@ -0,0 +1,44 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+/*
+ * This code implements the ECC algorithm used in SmartMedia.
+ *
+ * The ECC comprises 22 bits of parity information and is stuffed into 3 bytes.
+ * The two unused bit are set to 1.
+ * The ECC can correct single bit errors in a 256-byte page of data. Thus, two such ECC
+ * blocks are used on a 512-byte NAND page.
+ *
+ */
+
+#ifndef __YAFFS_ECC_H__
+#define __YAFFS_ECC_H__
+
+typedef struct {
+	unsigned char col_parity;
+	unsigned line_parity;
+	unsigned line_parity_prime;
+} yaffs_ecc_other;
+
+void yaffs_ecc_cacl(const unsigned char *data, unsigned char *ecc);
+int yaffs_ecc_correct(unsigned char *data, unsigned char *read_ecc,
+		const unsigned char *test_ecc);
+
+void yaffs_ecc_calc_other(const unsigned char *data, unsigned n_bytes,
+			yaffs_ecc_other *ecc);
+int yaffs_ecc_correct_other(unsigned char *data, unsigned n_bytes,
+			yaffs_ecc_other *read_ecc,
+			const yaffs_ecc_other *test_ecc);
+#endif
-- 
1.7.3.2.146.gca209

Re: [PATCH 08/29] Staging: yaffs2: yaffs_ecc: Add files

[Pekka Enberg]

On Mon, Nov 1, 2010 at 8:40 PM, Tracey Dent <tdent48227@gmail.com> wrote:
> Adding files to yaffs2 directory.
>
> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> ---
>  drivers/staging/yaffs2/yaffs_ecc.c |  323 ++++++++++++++++++++++++++++++++++++
>  drivers/staging/yaffs2/yaffs_ecc.h |   44 +++++
>  2 files changed, 367 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/yaffs2/yaffs_ecc.c
>  create mode 100644 drivers/staging/yaffs2/yaffs_ecc.h
>
> +
> +/* Count the bits in an unsigned char or a U32 */
> +
> +static int yaffs_count_bits(unsigned char x)
> +{
> +       int r = 0;
> +       while (x) {
> +               if (x & 1)
> +                       r++;
> +               x >>= 1;
> +       }
> +       return r;
> +}
> +
> +static int yaffs_count_bits32(unsigned x)
> +{
> +       int r = 0;
> +       while (x) {
> +               if (x & 1)
> +                       r++;
> +               x >>= 1;
> +       }
> +       return r;
> +}

Looks like bitmap_weight() to me.
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Re: [PATCH 08/29] Staging: yaffs2: yaffs_ecc: Add files

[Paul Mundt]

On Mon, Nov 01, 2010 at 02:40:56PM -0400, Tracey Dent wrote:
> +/*
> + * This code implements the ECC algorithm used in SmartMedia.
> + *
> + * The ECC comprises 22 bits of parity information and is stuffed into 3 bytes.
> + * The two unused bit are set to 1.
> + * The ECC can correct single bit errors in a 256-byte page of data. Thus, two such ECC
> + * blocks are used on a 512-byte NAND page.
> + *
> + */
> +
> +/* Table generated by gen-ecc.c
> + * Using a table means we do not have to calculate p1..p4 and p1'..p4'
> + * for each byte of data. These are instead provided in a table in bits7..2.
> + * Bit 0 of each entry indicates whether the entry has an odd or even parity, and therefore
> + * this bytes influence on the line parity.
> + */
> +
This all looks pretty generic. Have you considered just adding gen-ecc to
lib/, tying it in to hostprogs, and generating the tables during build
(see the crc32 code for reference)?

The rest of this would probably also be better off living in lib/ and
simply being selected by the YAFFS code as necessary.

> +/* Calculate the ECC for a 256-byte block of data */
> +void yaffs_ecc_cacl(const unsigned char *data, unsigned char *ecc)
> +void yaffs_ecc_calc_other(const unsigned char *data, unsigned n_bytes,
> +				yaffs_ecc_other *ecc_other)

Is there some reason for this naming inconistency?

[PATCH 09/29] Staging: yaffs2: yaffs_getblockinfo.h: Add file

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_getblockinfo.h |   35 +++++++++++++++++++++++++++
 1 files changed, 35 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_getblockinfo.h

diff --git a/drivers/staging/yaffs2/yaffs_getblockinfo.h b/drivers/staging/yaffs2/yaffs_getblockinfo.h
new file mode 100644
index 0000000..1c43b6c
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_getblockinfo.h
@@ -0,0 +1,35 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_GETBLOCKINFO_H__
+#define __YAFFS_GETBLOCKINFO_H__
+
+#include "yaffs_guts.h"
+#include "yaffs_trace.h"
+
+/* Function to manipulate block info */
+static Y_INLINE yaffs_block_info_t *yaffs_get_block_info(yaffs_dev_t * dev, int blk)
+{
+	if (blk < dev->internal_start_block || blk > dev->internal_end_block) {
+		T(YAFFS_TRACE_ERROR,
+		  (TSTR
+		   ("**>> yaffs: get_block_info block %d is not valid" TENDSTR),
+		   blk));
+		YBUG();
+	}
+	return &dev->block_info[blk - dev->internal_start_block];
+}
+
+#endif
-- 
1.7.3.2.146.gca209

[PATCH 10/29] Staging: yaffs2: yaffs_guts: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_guts.c | 5544 +++++++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_guts.h |  969 ++++++
 2 files changed, 6513 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_guts.c
 create mode 100644 drivers/staging/yaffs2/yaffs_guts.h

diff --git a/drivers/staging/yaffs2/yaffs_guts.c b/drivers/staging/yaffs2/yaffs_guts.c
new file mode 100644
index 0000000..eea828a
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_guts.c
@@ -0,0 +1,5544 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yportenv.h"
+#include "yaffs_trace.h"
+
+#include "yaffs_guts.h"
+#include "yaffs_tagsvalidity.h"
+#include "yaffs_getblockinfo.h"
+
+#include "yaffs_tagscompat.h"
+
+#include "yaffs_nand.h"
+
+#include "yaffs_yaffs1.h"
+#include "yaffs_yaffs2.h"
+#include "yaffs_bitmap.h"
+#include "yaffs_verify.h"
+
+#include "yaffs_nand.h"
+#include "yaffs_packedtags2.h"
+
+#include "yaffs_nameval.h"
+#include "yaffs_allocator.h"
+
+/* Note YAFFS_GC_GOOD_ENOUGH must be <= YAFFS_GC_PASSIVE_THRESHOLD */
+#define YAFFS_GC_GOOD_ENOUGH 2
+#define YAFFS_GC_PASSIVE_THRESHOLD 4
+
+#include "yaffs_ecc.h"
+
+
+
+/* Robustification (if it ever comes about...) */
+static void yaffs_retire_block(yaffs_dev_t *dev, int flash_block);
+static void yaffs_handle_chunk_wr_error(yaffs_dev_t *dev, int nand_chunk,
+		int erased_ok);
+static void yaffs_handle_chunk_wr_ok(yaffs_dev_t *dev, int nand_chunk,
+				const __u8 *data,
+				const yaffs_ext_tags *tags);
+static void yaffs_handle_chunk_update(yaffs_dev_t *dev, int nand_chunk,
+				const yaffs_ext_tags *tags);
+
+/* Other local prototypes */
+static void yaffs_update_parent(yaffs_obj_t *obj);
+static int yaffs_unlink_obj(yaffs_obj_t *obj);
+static int yaffs_obj_cache_dirty(yaffs_obj_t *obj);
+
+static int yaffs_write_new_chunk(yaffs_dev_t *dev,
+					const __u8 *buffer,
+					yaffs_ext_tags *tags,
+					int use_reserver);
+
+
+static yaffs_obj_t *yaffs_new_obj(yaffs_dev_t *dev, int number,
+					yaffs_obj_type type);
+
+
+static int yaffs_apply_xattrib_mod(yaffs_obj_t *obj, char *buffer, yaffs_xattr_mod *xmod);
+
+static void yaffs_remove_obj_from_dir(yaffs_obj_t *obj);
+static int yaffs_check_structures(void);
+static int yaffs_generic_obj_del(yaffs_obj_t *in);
+
+static int yaffs_check_chunk_erased(struct yaffs_dev_s *dev,
+				int nand_chunk);
+
+static int yaffs_unlink_worker(yaffs_obj_t *obj);
+
+static int yaffs_tags_match(const yaffs_ext_tags *tags, int obj_id,
+			int chunk_obj);
+
+static int yaffs_alloc_chunk(yaffs_dev_t *dev, int use_reserver,
+				yaffs_block_info_t **block_ptr);
+
+static void yaffs_check_obj_details_loaded(yaffs_obj_t *in);
+
+static void yaffs_invalidate_whole_cache(yaffs_obj_t *in);
+static void yaffs_invalidate_chunk_cache(yaffs_obj_t *object, int chunk_id);
+
+static int yaffs_find_chunk_in_file(yaffs_obj_t *in, int inode_chunk,
+				yaffs_ext_tags *tags);
+
+static int yaffs_verify_chunk_written(yaffs_dev_t *dev,
+					int nand_chunk,
+					const __u8 *data,
+					yaffs_ext_tags *tags);
+
+
+static void yaffs_load_name_from_oh(yaffs_dev_t *dev,YCHAR *name, const YCHAR *oh_name, int buff_size);
+static void yaffs_load_oh_from_name(yaffs_dev_t *dev,YCHAR *oh_name, const YCHAR *name);
+
+
+/* Function to calculate chunk and offset */
+
+static void yaffs_addr_to_chunk(yaffs_dev_t *dev, loff_t addr, int *chunk_out,
+		__u32 *offset_out)
+{
+	int chunk;
+	__u32 offset;
+
+	chunk  = (__u32)(addr >> dev->chunk_shift);
+
+	if (dev->chunk_div == 1) {
+		/* easy power of 2 case */
+		offset = (__u32)(addr & dev->chunk_mask);
+	} else {
+		/* Non power-of-2 case */
+
+		loff_t chunk_base;
+
+		chunk /= dev->chunk_div;
+
+		chunk_base = ((loff_t)chunk) * dev->data_bytes_per_chunk;
+		offset = (__u32)(addr - chunk_base);
+	}
+
+	*chunk_out = chunk;
+	*offset_out = offset;
+}
+
+/* Function to return the number of shifts for a power of 2 greater than or
+ * equal to the given number
+ * Note we don't try to cater for all possible numbers and this does not have to
+ * be hellishly efficient.
+ */
+
+static __u32 calc_shifts_ceiling(__u32 x)
+{
+	int extra_bits;
+	int shifts;
+
+	shifts = extra_bits = 0;
+
+	while (x > 1) {
+		if (x & 1)
+			extra_bits++;
+		x >>= 1;
+		shifts++;
+	}
+
+	if (extra_bits)
+		shifts++;
+
+	return shifts;
+}
+
+/* Function to return the number of shifts to get a 1 in bit 0
+ */
+
+static __u32 calc_shifts(__u32 x)
+{
+	__u32 shifts;
+
+	shifts =  0;
+
+	if (!x)
+		return 0;
+
+	while (!(x&1)) {
+		x >>= 1;
+		shifts++;
+	}
+
+	return shifts;
+}
+
+
+
+/*
+ * Temporary buffer manipulations.
+ */
+
+static int yaffs_init_tmp_buffers(yaffs_dev_t *dev)
+{
+	int i;
+	__u8 *buf = (__u8 *)1;
+
+	memset(dev->temp_buffer, 0, sizeof(dev->temp_buffer));
+
+	for (i = 0; buf && i < YAFFS_N_TEMP_BUFFERS; i++) {
+		dev->temp_buffer[i].line = 0;	/* not in use */
+		dev->temp_buffer[i].buffer = buf =
+		    YMALLOC_DMA(dev->param.total_bytes_per_chunk);
+	}
+
+	return buf ? YAFFS_OK : YAFFS_FAIL;
+}
+
+__u8 *yaffs_get_temp_buffer(yaffs_dev_t *dev, int line_no)
+{
+	int i, j;
+
+	dev->temp_in_use++;
+	if (dev->temp_in_use > dev->max_temp)
+		dev->max_temp = dev->temp_in_use;
+
+	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
+		if (dev->temp_buffer[i].line == 0) {
+			dev->temp_buffer[i].line = line_no;
+			if ((i + 1) > dev->max_temp) {
+				dev->max_temp = i + 1;
+				for (j = 0; j <= i; j++)
+					dev->temp_buffer[j].max_line =
+					    dev->temp_buffer[j].line;
+			}
+
+			return dev->temp_buffer[i].buffer;
+		}
+	}
+
+	T(YAFFS_TRACE_BUFFERS,
+	  (TSTR("Out of temp buffers at line %d, other held by lines:"),
+	   line_no));
+	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
+		T(YAFFS_TRACE_BUFFERS, (TSTR(" %d "), dev->temp_buffer[i].line));
+
+	T(YAFFS_TRACE_BUFFERS, (TSTR(" " TENDSTR)));
+
+	/*
+	 * If we got here then we have to allocate an unmanaged one
+	 * This is not good.
+	 */
+
+	dev->unmanaged_buffer_allocs++;
+	return YMALLOC(dev->data_bytes_per_chunk);
+
+}
+
+void yaffs_release_temp_buffer(yaffs_dev_t *dev, __u8 *buffer,
+				    int line_no)
+{
+	int i;
+
+	dev->temp_in_use--;
+
+	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
+		if (dev->temp_buffer[i].buffer == buffer) {
+			dev->temp_buffer[i].line = 0;
+			return;
+		}
+	}
+
+	if (buffer) {
+		/* assume it is an unmanaged one. */
+		T(YAFFS_TRACE_BUFFERS,
+		  (TSTR("Releasing unmanaged temp buffer in line %d" TENDSTR),
+		   line_no));
+		YFREE(buffer);
+		dev->unmanaged_buffer_deallocs++;
+	}
+
+}
+
+/*
+ * Determine if we have a managed buffer.
+ */
+int yaffs_is_managed_tmp_buffer(yaffs_dev_t *dev, const __u8 *buffer)
+{
+	int i;
+
+	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
+		if (dev->temp_buffer[i].buffer == buffer)
+			return 1;
+	}
+
+	for (i = 0; i < dev->param.n_caches; i++) {
+		if (dev->cache[i].data == buffer)
+			return 1;
+	}
+
+	if (buffer == dev->checkpt_buffer)
+		return 1;
+
+	T(YAFFS_TRACE_ALWAYS,
+		(TSTR("yaffs: unmaged buffer detected.\n" TENDSTR)));
+	return 0;
+}
+
+/*
+ * Verification code
+ */
+
+
+
+
+/*
+ *  Simple hash function. Needs to have a reasonable spread
+ */
+
+static Y_INLINE int yaffs_hash_fn(int n)
+{
+	n = abs(n);
+	return n % YAFFS_NOBJECT_BUCKETS;
+}
+
+/*
+ * Access functions to useful fake objects.
+ * Note that root might have a presence in NAND if permissions are set.
+ */
+
+yaffs_obj_t *yaffs_root(yaffs_dev_t *dev)
+{
+	return dev->root_dir;
+}
+
+yaffs_obj_t *yaffs_lost_n_found(yaffs_dev_t *dev)
+{
+	return dev->lost_n_found;
+}
+
+
+/*
+ *  Erased NAND checking functions
+ */
+
+int yaffs_check_ff(__u8 *buffer, int n_bytes)
+{
+	/* Horrible, slow implementation */
+	while (n_bytes--) {
+		if (*buffer != 0xFF)
+			return 0;
+		buffer++;
+	}
+	return 1;
+}
+
+static int yaffs_check_chunk_erased(struct yaffs_dev_s *dev,
+				int nand_chunk)
+{
+	int retval = YAFFS_OK;
+	__u8 *data = yaffs_get_temp_buffer(dev, __LINE__);
+	yaffs_ext_tags tags;
+	int result;
+
+	result = yaffs_rd_chunk_tags_nand(dev, nand_chunk, data, &tags);
+
+	if (tags.ecc_result > YAFFS_ECC_RESULT_NO_ERROR)
+		retval = YAFFS_FAIL;
+
+	if (!yaffs_check_ff(data, dev->data_bytes_per_chunk) || tags.chunk_used) {
+		T(YAFFS_TRACE_NANDACCESS,
+		  (TSTR("Chunk %d not erased" TENDSTR), nand_chunk));
+		retval = YAFFS_FAIL;
+	}
+
+	yaffs_release_temp_buffer(dev, data, __LINE__);
+
+	return retval;
+
+}
+
+
+static int yaffs_verify_chunk_written(yaffs_dev_t *dev,
+					int nand_chunk,
+					const __u8 *data,
+					yaffs_ext_tags *tags)
+{
+	int retval = YAFFS_OK;
+	yaffs_ext_tags temp_tags;
+	__u8 *buffer = yaffs_get_temp_buffer(dev,__LINE__);
+	int result;
+	
+	result = yaffs_rd_chunk_tags_nand(dev,nand_chunk,buffer,&temp_tags);
+	if(memcmp(buffer,data,dev->data_bytes_per_chunk) ||
+		temp_tags.obj_id != tags->obj_id ||
+		temp_tags.chunk_id  != tags->chunk_id ||
+		temp_tags.n_bytes != tags->n_bytes)
+		retval = YAFFS_FAIL;
+
+	yaffs_release_temp_buffer(dev, buffer, __LINE__);
+
+	return retval;
+}
+
+static int yaffs_write_new_chunk(struct yaffs_dev_s *dev,
+					const __u8 *data,
+					yaffs_ext_tags *tags,
+					int use_reserver)
+{
+	int attempts = 0;
+	int write_ok = 0;
+	int chunk;
+
+	yaffs2_checkpt_invalidate(dev);
+
+	do {
+		yaffs_block_info_t *bi = 0;
+		int erased_ok = 0;
+
+		chunk = yaffs_alloc_chunk(dev, use_reserver, &bi);
+		if (chunk < 0) {
+			/* no space */
+			break;
+		}
+
+		/* First check this chunk is erased, if it needs
+		 * checking.  The checking policy (unless forced
+		 * always on) is as follows:
+		 *
+		 * Check the first page we try to write in a block.
+		 * If the check passes then we don't need to check any
+		 * more.	If the check fails, we check again...
+		 * If the block has been erased, we don't need to check.
+		 *
+		 * However, if the block has been prioritised for gc,
+		 * then we think there might be something odd about
+		 * this block and stop using it.
+		 *
+		 * Rationale: We should only ever see chunks that have
+		 * not been erased if there was a partially written
+		 * chunk due to power loss.  This checking policy should
+		 * catch that case with very few checks and thus save a
+		 * lot of checks that are most likely not needed.
+		 *
+		 * Mods to the above
+		 * If an erase check fails or the write fails we skip the 
+		 * rest of the block.
+		 */
+
+		/* let's give it a try */
+		attempts++;
+
+		if(dev->param.always_check_erased)
+			bi->skip_erased_check = 0;
+
+		if (!bi->skip_erased_check) {
+			erased_ok = yaffs_check_chunk_erased(dev, chunk);
+			if (erased_ok != YAFFS_OK) {
+				T(YAFFS_TRACE_ERROR,
+				(TSTR("**>> yaffs chunk %d was not erased"
+				TENDSTR), chunk));
+
+				/* If not erased, delete this one,
+				 * skip rest of block and
+				 * try another chunk */
+				 yaffs_chunk_del(dev,chunk,1,__LINE__);
+				 yaffs_skip_rest_of_block(dev);
+				continue;
+			}
+		}
+
+		write_ok = yaffs_wr_chunk_tags_nand(dev, chunk,
+				data, tags);
+
+		if(!bi->skip_erased_check)
+			write_ok = yaffs_verify_chunk_written(dev, chunk, data, tags);
+
+		if (write_ok != YAFFS_OK) {
+			/* Clean up aborted write, skip to next block and
+			 * try another chunk */
+			yaffs_handle_chunk_wr_error(dev, chunk, erased_ok);
+			continue;
+		}
+
+		bi->skip_erased_check = 1;
+
+		/* Copy the data into the robustification buffer */
+		yaffs_handle_chunk_wr_ok(dev, chunk, data, tags);
+
+	} while (write_ok != YAFFS_OK &&
+		(yaffs_wr_attempts <= 0 || attempts <= yaffs_wr_attempts));
+
+	if (!write_ok)
+		chunk = -1;
+
+	if (attempts > 1) {
+		T(YAFFS_TRACE_ERROR,
+			(TSTR("**>> yaffs write required %d attempts" TENDSTR),
+			attempts));
+
+		dev->n_retired_writes += (attempts - 1);
+	}
+
+	return chunk;
+}
+
+
+ 
+/*
+ * Block retiring for handling a broken block.
+ */
+
+static void yaffs_retire_block(yaffs_dev_t *dev, int flash_block)
+{
+	yaffs_block_info_t *bi = yaffs_get_block_info(dev, flash_block);
+
+	yaffs2_checkpt_invalidate(dev);
+	
+	yaffs2_clear_oldest_dirty_seq(dev,bi);
+
+	if (yaffs_mark_bad(dev, flash_block) != YAFFS_OK) {
+		if (yaffs_erase_block(dev, flash_block) != YAFFS_OK) {
+			T(YAFFS_TRACE_ALWAYS, (TSTR(
+				"yaffs: Failed to mark bad and erase block %d"
+				TENDSTR), flash_block));
+		} else {
+			yaffs_ext_tags tags;
+			int chunk_id = flash_block * dev->param.chunks_per_block;
+
+			__u8 *buffer = yaffs_get_temp_buffer(dev, __LINE__);
+
+			memset(buffer, 0xff, dev->data_bytes_per_chunk);
+			yaffs_init_tags(&tags);
+			tags.seq_number = YAFFS_SEQUENCE_BAD_BLOCK;
+			if (dev->param.write_chunk_tags_fn(dev, chunk_id -
+				dev->chunk_offset, buffer, &tags) != YAFFS_OK)
+				T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Failed to "
+					TCONT("write bad block marker to block %d")
+					TENDSTR), flash_block));
+
+			yaffs_release_temp_buffer(dev, buffer, __LINE__);
+		}
+	}
+
+	bi->block_state = YAFFS_BLOCK_STATE_DEAD;
+	bi->gc_prioritise = 0;
+	bi->needs_retiring = 0;
+
+	dev->n_retired_blocks++;
+}
+
+/*
+ * Functions for robustisizing TODO
+ *
+ */
+
+static void yaffs_handle_chunk_wr_ok(yaffs_dev_t *dev, int nand_chunk,
+				const __u8 *data,
+				const yaffs_ext_tags *tags)
+{
+	dev=dev;
+	nand_chunk=nand_chunk;
+	data=data;
+	tags=tags;
+}
+
+static void yaffs_handle_chunk_update(yaffs_dev_t *dev, int nand_chunk,
+				const yaffs_ext_tags *tags)
+{
+	dev=dev;
+	nand_chunk=nand_chunk;
+	tags=tags;
+}
+
+void yaffs_handle_chunk_error(yaffs_dev_t *dev, yaffs_block_info_t *bi)
+{
+	if (!bi->gc_prioritise) {
+		bi->gc_prioritise = 1;
+		dev->has_pending_prioritised_gc = 1;
+		bi->chunk_error_strikes++;
+
+		if (bi->chunk_error_strikes > 3) {
+			bi->needs_retiring = 1; /* Too many stikes, so retire this */
+			T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Block struck out" TENDSTR)));
+
+		}
+	}
+}
+
+static void yaffs_handle_chunk_wr_error(yaffs_dev_t *dev, int nand_chunk,
+		int erased_ok)
+{
+	int flash_block = nand_chunk / dev->param.chunks_per_block;
+	yaffs_block_info_t *bi = yaffs_get_block_info(dev, flash_block);
+
+	yaffs_handle_chunk_error(dev, bi);
+
+	if (erased_ok) {
+		/* Was an actual write failure, so mark the block for retirement  */
+		bi->needs_retiring = 1;
+		T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
+		  (TSTR("**>> Block %d needs retiring" TENDSTR), flash_block));
+	}
+
+	/* Delete the chunk */
+	yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
+	yaffs_skip_rest_of_block(dev);
+}
+
+
+/*---------------- Name handling functions ------------*/
+
+static __u16 yaffs_calc_name_sum(const YCHAR *name)
+{
+	__u16 sum = 0;
+	__u16 i = 1;
+
+	const YUCHAR *bname = (const YUCHAR *) name;
+	if (bname) {
+		while ((*bname) && (i < (YAFFS_MAX_NAME_LENGTH/2))) {
+
+#ifdef CONFIG_YAFFS_CASE_INSENSITIVE
+			sum += yaffs_toupper(*bname) * i;
+#else
+			sum += (*bname) * i;
+#endif
+			i++;
+			bname++;
+		}
+	}
+	return sum;
+}
+
+void yaffs_set_obj_name(yaffs_obj_t *obj, const YCHAR *name)
+{
+#ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
+	memset(obj->short_name, 0, sizeof(YCHAR) * (YAFFS_SHORT_NAME_LENGTH+1));
+	if (name && yaffs_strnlen(name,YAFFS_SHORT_NAME_LENGTH+1) <= YAFFS_SHORT_NAME_LENGTH)
+		yaffs_strcpy(obj->short_name, name);
+	else
+		obj->short_name[0] = _Y('\0');
+#endif
+	obj->sum = yaffs_calc_name_sum(name);
+}
+
+void yaffs_set_obj_name_from_oh(yaffs_obj_t *obj, const yaffs_obj_header *oh)
+{
+#ifdef CONFIG_YAFFS_AUTO_UNICODE
+	YCHAR tmp_name[YAFFS_MAX_NAME_LENGTH+1];
+	memset(tmp_name,0,sizeof(tmp_name));
+	yaffs_load_name_from_oh(obj->my_dev,tmp_name,oh->name,YAFFS_MAX_NAME_LENGTH+1);
+	yaffs_set_obj_name(obj,tmp_name);
+#else
+	yaffs_set_obj_name(obj,oh->name);
+#endif
+}
+
+/*-------------------- TNODES -------------------
+
+ * List of spare tnodes
+ * The list is hooked together using the first pointer
+ * in the tnode.
+ */
+
+
+yaffs_tnode_t *yaffs_get_tnode(yaffs_dev_t *dev)
+{
+	yaffs_tnode_t *tn = yaffs_alloc_raw_tnode(dev);
+	if (tn){
+		memset(tn, 0, dev->tnode_size);
+		dev->n_tnodes++;
+	}
+
+	dev->checkpoint_blocks_required = 0; /* force recalculation*/
+
+	return tn;
+}
+
+/* FreeTnode frees up a tnode and puts it back on the free list */
+static void yaffs_free_tnode(yaffs_dev_t *dev, yaffs_tnode_t *tn)
+{
+	yaffs_free_raw_tnode(dev,tn);
+	dev->n_tnodes--;
+	dev->checkpoint_blocks_required = 0; /* force recalculation*/
+}
+
+static void yaffs_deinit_tnodes_and_objs(yaffs_dev_t *dev)
+{
+	yaffs_deinit_raw_tnodes_and_objs(dev);
+	dev->n_obj = 0;
+	dev->n_tnodes = 0;
+}
+
+
+void yaffs_load_tnode_0(yaffs_dev_t *dev, yaffs_tnode_t *tn, unsigned pos,
+		unsigned val)
+{
+	__u32 *map = (__u32 *)tn;
+	__u32 bit_in_map;
+	__u32 bit_in_word;
+	__u32 word_in_map;
+	__u32 mask;
+
+	pos &= YAFFS_TNODES_LEVEL0_MASK;
+	val >>= dev->chunk_grp_bits;
+
+	bit_in_map = pos * dev->tnode_width;
+	word_in_map = bit_in_map / 32;
+	bit_in_word = bit_in_map & (32 - 1);
+
+	mask = dev->tnode_mask << bit_in_word;
+
+	map[word_in_map] &= ~mask;
+	map[word_in_map] |= (mask & (val << bit_in_word));
+
+	if (dev->tnode_width > (32 - bit_in_word)) {
+		bit_in_word = (32 - bit_in_word);
+		word_in_map++;;
+		mask = dev->tnode_mask >> (/*dev->tnode_width -*/ bit_in_word);
+		map[word_in_map] &= ~mask;
+		map[word_in_map] |= (mask & (val >> bit_in_word));
+	}
+}
+
+__u32 yaffs_get_group_base(yaffs_dev_t *dev, yaffs_tnode_t *tn,
+		unsigned pos)
+{
+	__u32 *map = (__u32 *)tn;
+	__u32 bit_in_map;
+	__u32 bit_in_word;
+	__u32 word_in_map;
+	__u32 val;
+
+	pos &= YAFFS_TNODES_LEVEL0_MASK;
+
+	bit_in_map = pos * dev->tnode_width;
+	word_in_map = bit_in_map / 32;
+	bit_in_word = bit_in_map & (32 - 1);
+
+	val = map[word_in_map] >> bit_in_word;
+
+	if	(dev->tnode_width > (32 - bit_in_word)) {
+		bit_in_word = (32 - bit_in_word);
+		word_in_map++;;
+		val |= (map[word_in_map] << bit_in_word);
+	}
+
+	val &= dev->tnode_mask;
+	val <<= dev->chunk_grp_bits;
+
+	return val;
+}
+
+/* ------------------- End of individual tnode manipulation -----------------*/
+
+/* ---------Functions to manipulate the look-up tree (made up of tnodes) ------
+ * The look up tree is represented by the top tnode and the number of top_level
+ * in the tree. 0 means only the level 0 tnode is in the tree.
+ */
+
+/* FindLevel0Tnode finds the level 0 tnode, if one exists. */
+yaffs_tnode_t *yaffs_find_tnode_0(yaffs_dev_t *dev,
+					yaffs_file_s *file_struct,
+					__u32 chunk_id)
+{
+	yaffs_tnode_t *tn = file_struct->top;
+	__u32 i;
+	int required_depth;
+	int level = file_struct->top_level;
+
+	dev=dev;
+
+	/* Check sane level and chunk Id */
+	if (level < 0 || level > YAFFS_TNODES_MAX_LEVEL)
+		return NULL;
+
+	if (chunk_id > YAFFS_MAX_CHUNK_ID)
+		return NULL;
+
+	/* First check we're tall enough (ie enough top_level) */
+
+	i = chunk_id >> YAFFS_TNODES_LEVEL0_BITS;
+	required_depth = 0;
+	while (i) {
+		i >>= YAFFS_TNODES_INTERNAL_BITS;
+		required_depth++;
+	}
+
+	if (required_depth > file_struct->top_level)
+		return NULL; /* Not tall enough, so we can't find it */
+
+	/* Traverse down to level 0 */
+	while (level > 0 && tn) {
+		tn = tn->internal[(chunk_id >>
+			(YAFFS_TNODES_LEVEL0_BITS +
+				(level - 1) *
+				YAFFS_TNODES_INTERNAL_BITS)) &
+			YAFFS_TNODES_INTERNAL_MASK];
+		level--;
+	}
+
+	return tn;
+}
+
+/* AddOrFindLevel0Tnode finds the level 0 tnode if it exists, otherwise first expands the tree.
+ * This happens in two steps:
+ *  1. If the tree isn't tall enough, then make it taller.
+ *  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
+ *
+ * Used when modifying the tree.
+ *
+ *  If the tn argument is NULL, then a fresh tnode will be added otherwise the specified tn will
+ *  be plugged into the ttree.
+ */
+
+yaffs_tnode_t *yaffs_add_find_tnode_0(yaffs_dev_t *dev,
+					yaffs_file_s *file_struct,
+					__u32 chunk_id,
+					yaffs_tnode_t *passed_tn)
+{
+	int required_depth;
+	int i;
+	int l;
+	yaffs_tnode_t *tn;
+
+	__u32 x;
+
+
+	/* Check sane level and page Id */
+	if (file_struct->top_level < 0 || file_struct->top_level > YAFFS_TNODES_MAX_LEVEL)
+		return NULL;
+
+	if (chunk_id > YAFFS_MAX_CHUNK_ID)
+		return NULL;
+
+	/* First check we're tall enough (ie enough top_level) */
+
+	x = chunk_id >> YAFFS_TNODES_LEVEL0_BITS;
+	required_depth = 0;
+	while (x) {
+		x >>= YAFFS_TNODES_INTERNAL_BITS;
+		required_depth++;
+	}
+
+
+	if (required_depth > file_struct->top_level) {
+		/* Not tall enough, gotta make the tree taller */
+		for (i = file_struct->top_level; i < required_depth; i++) {
+
+			tn = yaffs_get_tnode(dev);
+
+			if (tn) {
+				tn->internal[0] = file_struct->top;
+				file_struct->top = tn;
+				file_struct->top_level++;
+			} else {
+				T(YAFFS_TRACE_ERROR,
+					(TSTR("yaffs: no more tnodes" TENDSTR)));
+				return NULL;
+			}
+		}
+	}
+
+	/* Traverse down to level 0, adding anything we need */
+
+	l = file_struct->top_level;
+	tn = file_struct->top;
+
+	if (l > 0) {
+		while (l > 0 && tn) {
+			x = (chunk_id >>
+			     (YAFFS_TNODES_LEVEL0_BITS +
+			      (l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
+			    YAFFS_TNODES_INTERNAL_MASK;
+
+
+			if ((l > 1) && !tn->internal[x]) {
+				/* Add missing non-level-zero tnode */
+				tn->internal[x] = yaffs_get_tnode(dev);
+				if(!tn->internal[x])
+					return NULL;
+			} else if (l == 1) {
+				/* Looking from level 1 at level 0 */
+				if (passed_tn) {
+					/* If we already have one, then release it.*/
+					if (tn->internal[x])
+						yaffs_free_tnode(dev, tn->internal[x]);
+					tn->internal[x] = passed_tn;
+
+				} else if (!tn->internal[x]) {
+					/* Don't have one, none passed in */
+					tn->internal[x] = yaffs_get_tnode(dev);
+					if(!tn->internal[x])
+						return NULL;
+				}
+			}
+
+			tn = tn->internal[x];
+			l--;
+		}
+	} else {
+		/* top is level 0 */
+		if (passed_tn) {
+			memcpy(tn, passed_tn, (dev->tnode_width * YAFFS_NTNODES_LEVEL0)/8);
+			yaffs_free_tnode(dev, passed_tn);
+		}
+	}
+
+	return tn;
+}
+
+static int yaffs_find_chunk_in_group(yaffs_dev_t *dev, int the_chunk,
+				yaffs_ext_tags *tags, int obj_id,
+				int inode_chunk)
+{
+	int j;
+
+	for (j = 0; the_chunk && j < dev->chunk_grp_size; j++) {
+		if (yaffs_check_chunk_bit(dev, the_chunk / dev->param.chunks_per_block,
+				the_chunk % dev->param.chunks_per_block)) {
+			
+			if(dev->chunk_grp_size == 1)
+				return the_chunk;
+			else {
+				yaffs_rd_chunk_tags_nand(dev, the_chunk, NULL,
+								tags);
+				if (yaffs_tags_match(tags, obj_id, inode_chunk)) {
+					/* found it; */
+					return the_chunk;
+				}
+			}
+		}
+		the_chunk++;
+	}
+	return -1;
+}
+
+#if 0
+/* Experimental code not being used yet. Might speed up file deletion */
+/* DeleteWorker scans backwards through the tnode tree and deletes all the
+ * chunks and tnodes in the file.
+ * Returns 1 if the tree was deleted.
+ * Returns 0 if it stopped early due to hitting the limit and the delete is incomplete.
+ */
+
+static int yaffs_del_worker(yaffs_obj_t *in, yaffs_tnode_t *tn, __u32 level,
+			      int chunk_offset, int *limit)
+{
+	int i;
+	int inode_chunk;
+	int the_chunk;
+	yaffs_ext_tags tags;
+	int found_chunk;
+	yaffs_dev_t *dev = in->my_dev;
+
+	int all_done = 1;
+
+	if (tn) {
+		if (level > 0) {
+			for (i = YAFFS_NTNODES_INTERNAL - 1; all_done && i >= 0;
+			     i--) {
+				if (tn->internal[i]) {
+					if (limit && (*limit) < 0) {
+						all_done = 0;
+					} else {
+						all_done =
+							yaffs_del_worker(in,
+								tn->
+								internal
+								[i],
+								level -
+								1,
+								(chunk_offset
+									<<
+									YAFFS_TNODES_INTERNAL_BITS)
+								+ i,
+								limit);
+					}
+					if (all_done) {
+						yaffs_free_tnode(dev,
+								tn->
+								internal[i]);
+						tn->internal[i] = NULL;
+					}
+				}
+			}
+			return (all_done) ? 1 : 0;
+		} else if (level == 0) {
+			int hit_limit = 0;
+
+			for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0 && !hit_limit;
+					i--) {
+				the_chunk = yaffs_get_group_base(dev, tn, i);
+				if (the_chunk) {
+
+					inode_chunk = (chunk_offset <<
+						YAFFS_TNODES_LEVEL0_BITS) + i;
+
+					found_chunk =
+						yaffs_find_chunk_in_group(dev,
+								the_chunk,
+								&tags,
+								in->obj_id,
+								inode_chunk);
+
+					if (found_chunk > 0) {
+						yaffs_chunk_del(dev,
+								  found_chunk, 1,
+								  __LINE__);
+						in->n_data_chunks--;
+						if (limit) {
+							*limit = *limit - 1;
+							if (*limit <= 0)
+								hit_limit = 1;
+						}
+
+					}
+
+					yaffs_load_tnode_0(dev, tn, i, 0);
+				}
+
+			}
+			return (i < 0) ? 1 : 0;
+
+		}
+
+	}
+
+	return 1;
+
+}
+
+#endif
+
+static void yaffs_soft_del_chunk(yaffs_dev_t *dev, int chunk)
+{
+	yaffs_block_info_t *the_block;
+	unsigned block_no;
+
+	T(YAFFS_TRACE_DELETION, (TSTR("soft delete chunk %d" TENDSTR), chunk));
+
+	block_no =  chunk / dev->param.chunks_per_block;
+	the_block = yaffs_get_block_info(dev, block_no);
+	if (the_block) {
+		the_block->soft_del_pages++;
+		dev->n_free_chunks++;
+		yaffs2_update_oldest_dirty_seq(dev, block_no, the_block);
+	}
+}
+
+/* SoftDeleteWorker scans backwards through the tnode tree and soft deletes all the chunks in the file.
+ * All soft deleting does is increment the block's softdelete count and pulls the chunk out
+ * of the tnode.
+ * Thus, essentially this is the same as DeleteWorker except that the chunks are soft deleted.
+ */
+
+static int yaffs_soft_del_worker(yaffs_obj_t *in, yaffs_tnode_t *tn,
+				  __u32 level, int chunk_offset)
+{
+	int i;
+	int the_chunk;
+	int all_done = 1;
+	yaffs_dev_t *dev = in->my_dev;
+
+	if (tn) {
+		if (level > 0) {
+
+			for (i = YAFFS_NTNODES_INTERNAL - 1; all_done && i >= 0;
+			     i--) {
+				if (tn->internal[i]) {
+					all_done =
+					    yaffs_soft_del_worker(in,
+								   tn->
+								   internal[i],
+								   level - 1,
+								   (chunk_offset
+								    <<
+								    YAFFS_TNODES_INTERNAL_BITS)
+								   + i);
+					if (all_done) {
+						yaffs_free_tnode(dev,
+								tn->
+								internal[i]);
+						tn->internal[i] = NULL;
+					} else {
+						/* Hoosterman... how could this happen? */
+					}
+				}
+			}
+			return (all_done) ? 1 : 0;
+		} else if (level == 0) {
+
+			for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
+				the_chunk = yaffs_get_group_base(dev, tn, i);
+				if (the_chunk) {
+					/* Note this does not find the real chunk, only the chunk group.
+					 * We make an assumption that a chunk group is not larger than
+					 * a block.
+					 */
+					yaffs_soft_del_chunk(dev, the_chunk);
+					yaffs_load_tnode_0(dev, tn, i, 0);
+				}
+
+			}
+			return 1;
+
+		}
+
+	}
+
+	return 1;
+
+}
+
+static void yaffs_soft_del_file(yaffs_obj_t *obj)
+{
+	if (obj->deleted &&
+	    obj->variant_type == YAFFS_OBJECT_TYPE_FILE && !obj->soft_del) {
+		if (obj->n_data_chunks <= 0) {
+			/* Empty file with no duplicate object headers, just delete it immediately */
+			yaffs_free_tnode(obj->my_dev,
+					obj->variant.file_variant.top);
+			obj->variant.file_variant.top = NULL;
+			T(YAFFS_TRACE_TRACING,
+			  (TSTR("yaffs: Deleting empty file %d" TENDSTR),
+			   obj->obj_id));
+			yaffs_generic_obj_del(obj);
+		} else {
+			yaffs_soft_del_worker(obj,
+					       obj->variant.file_variant.top,
+					       obj->variant.file_variant.
+					       top_level, 0);
+			obj->soft_del = 1;
+		}
+	}
+}
+
+/* Pruning removes any part of the file structure tree that is beyond the
+ * bounds of the file (ie that does not point to chunks).
+ *
+ * A file should only get pruned when its size is reduced.
+ *
+ * Before pruning, the chunks must be pulled from the tree and the
+ * level 0 tnode entries must be zeroed out.
+ * Could also use this for file deletion, but that's probably better handled
+ * by a special case.
+ *
+ * This function is recursive. For levels > 0 the function is called again on
+ * any sub-tree. For level == 0 we just check if the sub-tree has data.
+ * If there is no data in a subtree then it is pruned.
+ */
+
+static yaffs_tnode_t *yaffs_prune_worker(yaffs_dev_t *dev, yaffs_tnode_t *tn,
+				__u32 level, int del0)
+{
+	int i;
+	int has_data;
+
+	if (tn) {
+		has_data = 0;
+
+		if(level > 0){
+			for (i = 0; i < YAFFS_NTNODES_INTERNAL; i++) {
+				if (tn->internal[i]) {
+					tn->internal[i] =
+						yaffs_prune_worker(dev, tn->internal[i],
+							level - 1,
+							(i == 0) ? del0 : 1);
+				}
+
+				if (tn->internal[i])
+					has_data++;
+			}
+		} else {
+			int tnode_size_u32 = dev->tnode_size/sizeof(__u32);
+			__u32 *map = (__u32 *)tn;
+
+                        for(i = 0; !has_data && i < tnode_size_u32; i++){
+                                if(map[i])
+                                        has_data++;
+                        }
+                }
+
+		if (has_data == 0 && del0) {
+			/* Free and return NULL */
+
+			yaffs_free_tnode(dev, tn);
+			tn = NULL;
+		}
+
+	}
+
+	return tn;
+
+}
+
+static int yaffs_prune_tree(yaffs_dev_t *dev,
+				yaffs_file_s *file_struct)
+{
+	int i;
+	int has_data;
+	int done = 0;
+	yaffs_tnode_t *tn;
+
+	if (file_struct->top_level > 0) {
+		file_struct->top =
+		    yaffs_prune_worker(dev, file_struct->top, file_struct->top_level, 0);
+
+		/* Now we have a tree with all the non-zero branches NULL but the height
+		 * is the same as it was.
+		 * Let's see if we can trim internal tnodes to shorten the tree.
+		 * We can do this if only the 0th element in the tnode is in use
+		 * (ie all the non-zero are NULL)
+		 */
+
+		while (file_struct->top_level && !done) {
+			tn = file_struct->top;
+
+			has_data = 0;
+			for (i = 1; i < YAFFS_NTNODES_INTERNAL; i++) {
+				if (tn->internal[i])
+					has_data++;
+			}
+
+			if (!has_data) {
+				file_struct->top = tn->internal[0];
+				file_struct->top_level--;
+				yaffs_free_tnode(dev, tn);
+			} else {
+				done = 1;
+			}
+		}
+	}
+
+	return YAFFS_OK;
+}
+
+/*-------------------- End of File Structure functions.-------------------*/
+
+
+/* AllocateEmptyObject gets us a clean Object. Tries to make allocate more if we run out */
+static yaffs_obj_t *yaffs_alloc_empty_obj(yaffs_dev_t *dev)
+{
+	yaffs_obj_t *obj = yaffs_alloc_raw_obj(dev);
+
+	if (obj) {
+		dev->n_obj++;
+
+		/* Now sweeten it up... */
+
+		memset(obj, 0, sizeof(yaffs_obj_t));
+		obj->being_created = 1;
+
+		obj->my_dev = dev;
+		obj->hdr_chunk = 0;
+		obj->variant_type = YAFFS_OBJECT_TYPE_UNKNOWN;
+		YINIT_LIST_HEAD(&(obj->hard_links));
+		YINIT_LIST_HEAD(&(obj->hash_link));
+		YINIT_LIST_HEAD(&obj->siblings);
+
+
+		/* Now make the directory sane */
+		if (dev->root_dir) {
+			obj->parent = dev->root_dir;
+			ylist_add(&(obj->siblings), &dev->root_dir->variant.dir_variant.children);
+		}
+
+		/* Add it to the lost and found directory.
+		 * NB Can't put root or lost-n-found in lost-n-found so
+		 * check if lost-n-found exists first
+		 */
+		if (dev->lost_n_found)
+			yaffs_add_obj_to_dir(dev->lost_n_found, obj);
+
+		obj->being_created = 0;
+	}
+
+	dev->checkpoint_blocks_required = 0; /* force recalculation*/
+
+	return obj;
+}
+
+static yaffs_obj_t *yaffs_create_fake_dir(yaffs_dev_t *dev, int number,
+					       __u32 mode)
+{
+
+	yaffs_obj_t *obj =
+	    yaffs_new_obj(dev, number, YAFFS_OBJECT_TYPE_DIRECTORY);
+	if (obj) {
+		obj->fake = 1;		/* it is fake so it might have no NAND presence... */
+		obj->rename_allowed = 0;	/* ... and we're not allowed to rename it... */
+		obj->unlink_allowed = 0;	/* ... or unlink it */
+		obj->deleted = 0;
+		obj->unlinked = 0;
+		obj->yst_mode = mode;
+		obj->my_dev = dev;
+		obj->hdr_chunk = 0;	/* Not a valid chunk. */
+	}
+
+	return obj;
+
+}
+
+static void yaffs_unhash_obj(yaffs_obj_t *obj)
+{
+	int bucket;
+	yaffs_dev_t *dev = obj->my_dev;
+
+	/* If it is still linked into the bucket list, free from the list */
+	if (!ylist_empty(&obj->hash_link)) {
+		ylist_del_init(&obj->hash_link);
+		bucket = yaffs_hash_fn(obj->obj_id);
+		dev->obj_bucket[bucket].count--;
+	}
+}
+
+/*  FreeObject frees up a Object and puts it back on the free list */
+static void yaffs_free_obj(yaffs_obj_t *obj)
+{
+	yaffs_dev_t *dev = obj->my_dev;
+
+	T(YAFFS_TRACE_OS, (TSTR("FreeObject %p inode %p"TENDSTR), obj, obj->my_inode));
+
+	if (!obj)
+		YBUG();
+	if (obj->parent)
+		YBUG();
+	if (!ylist_empty(&obj->siblings))
+		YBUG();
+
+
+	if (obj->my_inode) {
+		/* We're still hooked up to a cached inode.
+		 * Don't delete now, but mark for later deletion
+		 */
+		obj->defered_free = 1;
+		return;
+	}
+
+	yaffs_unhash_obj(obj);
+
+	yaffs_free_raw_obj(dev,obj);
+	dev->n_obj--;
+	dev->checkpoint_blocks_required = 0; /* force recalculation*/
+}
+
+
+void yaffs_handle_defered_free(yaffs_obj_t *obj)
+{
+	if (obj->defered_free)
+		yaffs_free_obj(obj);
+}
+
+static void yaffs_init_tnodes_and_objs(yaffs_dev_t *dev)
+{
+	int i;
+
+	dev->n_obj = 0;
+	dev->n_tnodes = 0;
+
+	yaffs_init_raw_tnodes_and_objs(dev);
+
+	for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
+		YINIT_LIST_HEAD(&dev->obj_bucket[i].list);
+		dev->obj_bucket[i].count = 0;
+	}
+}
+
+static int yaffs_find_nice_bucket(yaffs_dev_t *dev)
+{
+	int i;
+	int l = 999;
+	int lowest = 999999;
+
+
+	/* Search for the shortest list or one that
+	 * isn't too long.
+	 */
+
+	for (i = 0; i < 10 && lowest > 4; i++) {
+		dev->bucket_finder++;
+		dev->bucket_finder %= YAFFS_NOBJECT_BUCKETS;
+		if (dev->obj_bucket[dev->bucket_finder].count < lowest) {
+			lowest = dev->obj_bucket[dev->bucket_finder].count;
+			l = dev->bucket_finder;
+		}
+
+	}
+
+	return l;
+}
+
+static int yaffs_new_obj_id(yaffs_dev_t *dev)
+{
+	int bucket = yaffs_find_nice_bucket(dev);
+
+	/* Now find an object value that has not already been taken
+	 * by scanning the list.
+	 */
+
+	int found = 0;
+	struct ylist_head *i;
+
+	__u32 n = (__u32) bucket;
+
+	/* yaffs_check_obj_hash_sane();  */
+
+	while (!found) {
+		found = 1;
+		n += YAFFS_NOBJECT_BUCKETS;
+		if (1 || dev->obj_bucket[bucket].count > 0) {
+			ylist_for_each(i, &dev->obj_bucket[bucket].list) {
+				/* If there is already one in the list */
+				if (i && ylist_entry(i, yaffs_obj_t,
+						hash_link)->obj_id == n) {
+					found = 0;
+				}
+			}
+		}
+	}
+
+	return n;
+}
+
+static void yaffs_hash_obj(yaffs_obj_t *in)
+{
+	int bucket = yaffs_hash_fn(in->obj_id);
+	yaffs_dev_t *dev = in->my_dev;
+
+	ylist_add(&in->hash_link, &dev->obj_bucket[bucket].list);
+	dev->obj_bucket[bucket].count++;
+}
+
+yaffs_obj_t *yaffs_find_by_number(yaffs_dev_t *dev, __u32 number)
+{
+	int bucket = yaffs_hash_fn(number);
+	struct ylist_head *i;
+	yaffs_obj_t *in;
+
+	ylist_for_each(i, &dev->obj_bucket[bucket].list) {
+		/* Look if it is in the list */
+		if (i) {
+			in = ylist_entry(i, yaffs_obj_t, hash_link);
+			if (in->obj_id == number) {
+
+				/* Don't tell the VFS about this one if it is defered free */
+				if (in->defered_free)
+					return NULL;
+
+				return in;
+			}
+		}
+	}
+
+	return NULL;
+}
+
+yaffs_obj_t *yaffs_new_obj(yaffs_dev_t *dev, int number,
+				    yaffs_obj_type type)
+{
+	yaffs_obj_t *the_obj=NULL;
+	yaffs_tnode_t *tn = NULL;
+
+	if (number < 0)
+		number = yaffs_new_obj_id(dev);
+
+	if (type == YAFFS_OBJECT_TYPE_FILE) {
+		tn = yaffs_get_tnode(dev);
+		if (!tn)
+			return NULL;
+	}
+
+	the_obj = yaffs_alloc_empty_obj(dev);
+	if (!the_obj){
+		if(tn)
+			yaffs_free_tnode(dev,tn);
+		return NULL;
+	}
+
+
+	if (the_obj) {
+		the_obj->fake = 0;
+		the_obj->rename_allowed = 1;
+		the_obj->unlink_allowed = 1;
+		the_obj->obj_id = number;
+		yaffs_hash_obj(the_obj);
+		the_obj->variant_type = type;
+#ifdef CONFIG_YAFFS_WINCE
+		yfsd_win_file_time_now(the_obj->win_atime);
+		the_obj->win_ctime[0] = the_obj->win_mtime[0] =
+		    the_obj->win_atime[0];
+		the_obj->win_ctime[1] = the_obj->win_mtime[1] =
+		    the_obj->win_atime[1];
+
+#else
+
+		the_obj->yst_atime = the_obj->yst_mtime =
+		    the_obj->yst_ctime = Y_CURRENT_TIME;
+#endif
+		switch (type) {
+		case YAFFS_OBJECT_TYPE_FILE:
+			the_obj->variant.file_variant.file_size = 0;
+			the_obj->variant.file_variant.scanned_size = 0;
+			the_obj->variant.file_variant.shrink_size = 0xFFFFFFFF;	/* max __u32 */
+			the_obj->variant.file_variant.top_level = 0;
+			the_obj->variant.file_variant.top = tn;
+			break;
+		case YAFFS_OBJECT_TYPE_DIRECTORY:
+			YINIT_LIST_HEAD(&the_obj->variant.dir_variant.
+					children);
+			YINIT_LIST_HEAD(&the_obj->variant.dir_variant.
+					dirty);
+			break;
+		case YAFFS_OBJECT_TYPE_SYMLINK:
+		case YAFFS_OBJECT_TYPE_HARDLINK:
+		case YAFFS_OBJECT_TYPE_SPECIAL:
+			/* No action required */
+			break;
+		case YAFFS_OBJECT_TYPE_UNKNOWN:
+			/* todo this should not happen */
+			break;
+		}
+	}
+
+	return the_obj;
+}
+
+yaffs_obj_t *yaffs_find_or_create_by_number(yaffs_dev_t *dev,
+						int number,
+						yaffs_obj_type type)
+{
+	yaffs_obj_t *the_obj = NULL;
+
+	if (number > 0)
+		the_obj = yaffs_find_by_number(dev, number);
+
+	if (!the_obj)
+		the_obj = yaffs_new_obj(dev, number, type);
+
+	return the_obj;
+
+}
+
+
+YCHAR *yaffs_clone_str(const YCHAR *str)
+{
+	YCHAR *new_str = NULL;
+	int len;
+
+	if (!str)
+		str = _Y("");
+
+	len = yaffs_strnlen(str,YAFFS_MAX_ALIAS_LENGTH);
+	new_str = YMALLOC((len + 1) * sizeof(YCHAR));
+	if (new_str){
+		yaffs_strncpy(new_str, str,len);
+		new_str[len] = 0;
+	}
+	return new_str;
+
+}
+
+/*
+ * Mknod (create) a new object.
+ * equiv_obj only has meaning for a hard link;
+ * alias_str only has meaning for a symlink.
+ * rdev only has meaning for devices (a subset of special objects)
+ */
+
+static yaffs_obj_t *yaffs_create_obj(yaffs_obj_type type,
+				       yaffs_obj_t *parent,
+				       const YCHAR *name,
+				       __u32 mode,
+				       __u32 uid,
+				       __u32 gid,
+				       yaffs_obj_t *equiv_obj,
+				       const YCHAR *alias_str, __u32 rdev)
+{
+	yaffs_obj_t *in;
+	YCHAR *str = NULL;
+
+	yaffs_dev_t *dev = parent->my_dev;
+
+	/* Check if the entry exists. If it does then fail the call since we don't want a dup.*/
+	if (yaffs_find_by_name(parent, name))
+		return NULL;
+
+	if (type == YAFFS_OBJECT_TYPE_SYMLINK) {
+		str = yaffs_clone_str(alias_str);
+		if (!str)
+			return NULL;
+	}
+
+	in = yaffs_new_obj(dev, -1, type);
+
+	if (!in){
+		if(str)
+			YFREE(str);
+		return NULL;
+	}
+
+
+
+
+
+	if (in) {
+		in->hdr_chunk = 0;
+		in->valid = 1;
+		in->variant_type = type;
+
+		in->yst_mode = mode;
+
+#ifdef CONFIG_YAFFS_WINCE
+		yfsd_win_file_time_now(in->win_atime);
+		in->win_ctime[0] = in->win_mtime[0] = in->win_atime[0];
+		in->win_ctime[1] = in->win_mtime[1] = in->win_atime[1];
+
+#else
+		in->yst_atime = in->yst_mtime = in->yst_ctime = Y_CURRENT_TIME;
+
+		in->yst_rdev = rdev;
+		in->yst_uid = uid;
+		in->yst_gid = gid;
+#endif
+		in->n_data_chunks = 0;
+
+		yaffs_set_obj_name(in, name);
+		in->dirty = 1;
+
+		yaffs_add_obj_to_dir(parent, in);
+
+		in->my_dev = parent->my_dev;
+
+		switch (type) {
+		case YAFFS_OBJECT_TYPE_SYMLINK:
+			in->variant.symlink_variant.alias = str;
+			break;
+		case YAFFS_OBJECT_TYPE_HARDLINK:
+			in->variant.hardlink_variant.equiv_obj =
+				equiv_obj;
+			in->variant.hardlink_variant.equiv_id =
+				equiv_obj->obj_id;
+			ylist_add(&in->hard_links, &equiv_obj->hard_links);
+			break;
+		case YAFFS_OBJECT_TYPE_FILE:
+		case YAFFS_OBJECT_TYPE_DIRECTORY:
+		case YAFFS_OBJECT_TYPE_SPECIAL:
+		case YAFFS_OBJECT_TYPE_UNKNOWN:
+			/* do nothing */
+			break;
+		}
+
+		if (yaffs_update_oh(in, name, 0, 0, 0, NULL) < 0) {
+			/* Could not create the object header, fail the creation */
+			yaffs_del_obj(in);
+			in = NULL;
+		}
+
+		yaffs_update_parent(parent);
+	}
+
+	return in;
+}
+
+yaffs_obj_t *yaffs_create_file(yaffs_obj_t *parent, const YCHAR *name,
+			__u32 mode, __u32 uid, __u32 gid)
+{
+	return yaffs_create_obj(YAFFS_OBJECT_TYPE_FILE, parent, name, mode,
+				uid, gid, NULL, NULL, 0);
+}
+
+yaffs_obj_t *yaffs_create_dir(yaffs_obj_t *parent, const YCHAR *name,
+				__u32 mode, __u32 uid, __u32 gid)
+{
+	return yaffs_create_obj(YAFFS_OBJECT_TYPE_DIRECTORY, parent, name,
+				 mode, uid, gid, NULL, NULL, 0);
+}
+
+yaffs_obj_t *yaffs_create_special(yaffs_obj_t *parent, const YCHAR *name,
+				__u32 mode, __u32 uid, __u32 gid, __u32 rdev)
+{
+	return yaffs_create_obj(YAFFS_OBJECT_TYPE_SPECIAL, parent, name, mode,
+				 uid, gid, NULL, NULL, rdev);
+}
+
+yaffs_obj_t *yaffs_create_symlink(yaffs_obj_t *parent, const YCHAR *name,
+				__u32 mode, __u32 uid, __u32 gid,
+				const YCHAR *alias)
+{
+	return yaffs_create_obj(YAFFS_OBJECT_TYPE_SYMLINK, parent, name, mode,
+				uid, gid, NULL, alias, 0);
+}
+
+/* yaffs_link_obj returns the object id of the equivalent object.*/
+yaffs_obj_t *yaffs_link_obj(yaffs_obj_t *parent, const YCHAR *name,
+			yaffs_obj_t *equiv_obj)
+{
+	/* Get the real object in case we were fed a hard link as an equivalent object */
+	equiv_obj = yaffs_get_equivalent_obj(equiv_obj);
+
+	if (yaffs_create_obj
+	    (YAFFS_OBJECT_TYPE_HARDLINK, parent, name, 0, 0, 0,
+	     equiv_obj, NULL, 0)) {
+		return equiv_obj;
+	} else {
+		return NULL;
+	}
+
+}
+
+static int yaffs_change_obj_name(yaffs_obj_t *obj, yaffs_obj_t *new_dir,
+				const YCHAR *new_name, int force, int shadows)
+{
+	int unlink_op;
+	int del_op;
+
+	yaffs_obj_t *existing_target;
+
+	if (new_dir == NULL)
+		new_dir = obj->parent;	/* use the old directory */
+
+	if (new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("tragedy: yaffs_change_obj_name: new_dir is not a directory"
+		    TENDSTR)));
+		YBUG();
+	}
+
+	/* TODO: Do we need this different handling for YAFFS2 and YAFFS1?? */
+	if (obj->my_dev->param.is_yaffs2)
+		unlink_op = (new_dir == obj->my_dev->unlinked_dir);
+	else
+		unlink_op = (new_dir == obj->my_dev->unlinked_dir
+			    && obj->variant_type == YAFFS_OBJECT_TYPE_FILE);
+
+	del_op = (new_dir == obj->my_dev->del_dir);
+
+	existing_target = yaffs_find_by_name(new_dir, new_name);
+
+	/* If the object is a file going into the unlinked directory,
+	 *   then it is OK to just stuff it in since duplicate names are allowed.
+	 *   else only proceed if the new name does not exist and if we're putting
+	 *   it into a directory.
+	 */
+	if ((unlink_op ||
+	     del_op ||
+	     force ||
+	     (shadows > 0) ||
+	     !existing_target) &&
+	    new_dir->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY) {
+		yaffs_set_obj_name(obj, new_name);
+		obj->dirty = 1;
+
+		yaffs_add_obj_to_dir(new_dir, obj);
+
+		if (unlink_op)
+			obj->unlinked = 1;
+
+		/* If it is a deletion then we mark it as a shrink for gc purposes. */
+		if (yaffs_update_oh(obj, new_name, 0, del_op, shadows, NULL) >= 0)
+			return YAFFS_OK;
+	}
+
+	return YAFFS_FAIL;
+}
+
+int yaffs_rename_obj(yaffs_obj_t *old_dir, const YCHAR *old_name,
+		yaffs_obj_t *new_dir, const YCHAR *new_name)
+{
+	yaffs_obj_t *obj = NULL;
+	yaffs_obj_t *existing_target = NULL;
+	int force = 0;
+	int result;
+	yaffs_dev_t *dev;
+
+
+	if (!old_dir || old_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
+		YBUG();
+	if (!new_dir || new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
+		YBUG();
+
+	dev = old_dir->my_dev;
+
+#ifdef CONFIG_YAFFS_CASE_INSENSITIVE
+	/* Special case for case insemsitive systems (eg. WinCE).
+	 * While look-up is case insensitive, the name isn't.
+	 * Therefore we might want to change x.txt to X.txt
+	*/
+	if (old_dir == new_dir && yaffs_strcmp(old_name, new_name) == 0)
+		force = 1;
+#endif
+
+	if(yaffs_strnlen(new_name,YAFFS_MAX_NAME_LENGTH+1) > YAFFS_MAX_NAME_LENGTH)
+		/* ENAMETOOLONG */
+		return YAFFS_FAIL;
+
+	obj = yaffs_find_by_name(old_dir, old_name);
+
+	if (obj && obj->rename_allowed) {
+
+		/* Now do the handling for an existing target, if there is one */
+
+		existing_target = yaffs_find_by_name(new_dir, new_name);
+		if (existing_target &&
+			existing_target->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY &&
+			!ylist_empty(&existing_target->variant.dir_variant.children)) {
+			/* There is a target that is a non-empty directory, so we fail */
+			return YAFFS_FAIL;	/* EEXIST or ENOTEMPTY */
+		} else if (existing_target && existing_target != obj) {
+			/* Nuke the target first, using shadowing,
+			 * but only if it isn't the same object.
+			 *
+			 * Note we must disable gc otherwise it can mess up the shadowing.
+			 *
+			 */
+			dev->gc_disable=1;
+			yaffs_change_obj_name(obj, new_dir, new_name, force,
+						existing_target->obj_id);
+			existing_target->is_shadowed = 1;
+			yaffs_unlink_obj(existing_target);
+			dev->gc_disable=0;
+		}
+
+		result = yaffs_change_obj_name(obj, new_dir, new_name, 1, 0);
+
+		yaffs_update_parent(old_dir);
+		if(new_dir != old_dir)
+			yaffs_update_parent(new_dir);
+		
+		return result;
+	}
+	return YAFFS_FAIL;
+}
+
+/*------------------------- Block Management and Page Allocation ----------------*/
+
+static int yaffs_init_blocks(yaffs_dev_t *dev)
+{
+	int n_blocks = dev->internal_end_block - dev->internal_start_block + 1;
+
+	dev->block_info = NULL;
+	dev->chunk_bits = NULL;
+
+	dev->alloc_block = -1;	/* force it to get a new one */
+
+	/* If the first allocation strategy fails, thry the alternate one */
+	dev->block_info = YMALLOC(n_blocks * sizeof(yaffs_block_info_t));
+	if (!dev->block_info) {
+		dev->block_info = YMALLOC_ALT(n_blocks * sizeof(yaffs_block_info_t));
+		dev->block_info_alt = 1;
+	} else
+		dev->block_info_alt = 0;
+
+	if (dev->block_info) {
+		/* Set up dynamic blockinfo stuff. */
+		dev->chunk_bit_stride = (dev->param.chunks_per_block + 7) / 8; /* round up bytes */
+		dev->chunk_bits = YMALLOC(dev->chunk_bit_stride * n_blocks);
+		if (!dev->chunk_bits) {
+			dev->chunk_bits = YMALLOC_ALT(dev->chunk_bit_stride * n_blocks);
+			dev->chunk_bits_alt = 1;
+		} else
+			dev->chunk_bits_alt = 0;
+	}
+
+	if (dev->block_info && dev->chunk_bits) {
+		memset(dev->block_info, 0, n_blocks * sizeof(yaffs_block_info_t));
+		memset(dev->chunk_bits, 0, dev->chunk_bit_stride * n_blocks);
+		return YAFFS_OK;
+	}
+
+	return YAFFS_FAIL;
+}
+
+static void yaffs_deinit_blocks(yaffs_dev_t *dev)
+{
+	if (dev->block_info_alt && dev->block_info)
+		YFREE_ALT(dev->block_info);
+	else if (dev->block_info)
+		YFREE(dev->block_info);
+
+	dev->block_info_alt = 0;
+
+	dev->block_info = NULL;
+
+	if (dev->chunk_bits_alt && dev->chunk_bits)
+		YFREE_ALT(dev->chunk_bits);
+	else if (dev->chunk_bits)
+		YFREE(dev->chunk_bits);
+	dev->chunk_bits_alt = 0;
+	dev->chunk_bits = NULL;
+}
+
+void yaffs_block_became_dirty(yaffs_dev_t *dev, int block_no)
+{
+	yaffs_block_info_t *bi = yaffs_get_block_info(dev, block_no);
+
+	int erased_ok = 0;
+
+	/* If the block is still healthy erase it and mark as clean.
+	 * If the block has had a data failure, then retire it.
+	 */
+
+	T(YAFFS_TRACE_GC | YAFFS_TRACE_ERASE,
+		(TSTR("yaffs_block_became_dirty block %d state %d %s"TENDSTR),
+		block_no, bi->block_state, (bi->needs_retiring) ? "needs retiring" : ""));
+
+	yaffs2_clear_oldest_dirty_seq(dev,bi);
+
+	bi->block_state = YAFFS_BLOCK_STATE_DIRTY;
+
+	/* If this is the block being garbage collected then stop gc'ing this block */
+	if(block_no == dev->gc_block)
+		dev->gc_block = 0;
+
+	/* If this block is currently the best candidate for gc then drop as a candidate */
+	if(block_no == dev->gc_dirtiest){
+		dev->gc_dirtiest = 0;
+		dev->gc_pages_in_use = 0;
+	}
+
+	if (!bi->needs_retiring) {
+		yaffs2_checkpt_invalidate(dev);
+		erased_ok = yaffs_erase_block(dev, block_no);
+		if (!erased_ok) {
+			dev->n_erase_failures++;
+			T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
+			  (TSTR("**>> Erasure failed %d" TENDSTR), block_no));
+		}
+	}
+
+	if (erased_ok &&
+	    ((yaffs_trace_mask & YAFFS_TRACE_ERASE) || !yaffs_skip_verification(dev))) {
+		int i;
+		for (i = 0; i < dev->param.chunks_per_block; i++) {
+			if (!yaffs_check_chunk_erased
+			    (dev, block_no * dev->param.chunks_per_block + i)) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   (">>Block %d erasure supposedly OK, but chunk %d not erased"
+				    TENDSTR), block_no, i));
+			}
+		}
+	}
+
+	if (erased_ok) {
+		/* Clean it up... */
+		bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
+		bi->seq_number = 0;
+		dev->n_erased_blocks++;
+		bi->pages_in_use = 0;
+		bi->soft_del_pages = 0;
+		bi->has_shrink_hdr = 0;
+		bi->skip_erased_check = 1;  /* This is clean, so no need to check */
+		bi->gc_prioritise = 0;
+		yaffs_clear_chunk_bits(dev, block_no);
+
+		T(YAFFS_TRACE_ERASE,
+		  (TSTR("Erased block %d" TENDSTR), block_no));
+	} else {
+		dev->n_free_chunks -= dev->param.chunks_per_block;	/* We lost a block of free space */
+
+		yaffs_retire_block(dev, block_no);
+		T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
+		  (TSTR("**>> Block %d retired" TENDSTR), block_no));
+	}
+}
+
+static int yaffs_find_alloc_block(yaffs_dev_t *dev)
+{
+	int i;
+
+	yaffs_block_info_t *bi;
+
+	if (dev->n_erased_blocks < 1) {
+		/* Hoosterman we've got a problem.
+		 * Can't get space to gc
+		 */
+		T(YAFFS_TRACE_ERROR,
+		  (TSTR("yaffs tragedy: no more erased blocks" TENDSTR)));
+
+		return -1;
+	}
+
+	/* Find an empty block. */
+
+	for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
+		dev->alloc_block_finder++;
+		if (dev->alloc_block_finder < dev->internal_start_block
+		    || dev->alloc_block_finder > dev->internal_end_block) {
+			dev->alloc_block_finder = dev->internal_start_block;
+		}
+
+		bi = yaffs_get_block_info(dev, dev->alloc_block_finder);
+
+		if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
+			bi->block_state = YAFFS_BLOCK_STATE_ALLOCATING;
+			dev->seq_number++;
+			bi->seq_number = dev->seq_number;
+			dev->n_erased_blocks--;
+			T(YAFFS_TRACE_ALLOCATE,
+			  (TSTR("Allocated block %d, seq  %d, %d left" TENDSTR),
+			   dev->alloc_block_finder, dev->seq_number,
+			   dev->n_erased_blocks));
+			return dev->alloc_block_finder;
+		}
+	}
+
+	T(YAFFS_TRACE_ALWAYS,
+	  (TSTR
+	   ("yaffs tragedy: no more erased blocks, but there should have been %d"
+	    TENDSTR), dev->n_erased_blocks));
+
+	return -1;
+}
+
+
+/*
+ * Check if there's space to allocate...
+ * Thinks.... do we need top make this ths same as yaffs_get_free_chunks()?
+ */
+int yaffs_check_alloc_available(yaffs_dev_t *dev, int n_chunks)
+{
+	int reserved_chunks;
+	int reserved_blocks = dev->param.n_reserved_blocks;
+	int checkpt_blocks;
+
+	checkpt_blocks = yaffs_calc_checkpt_blocks_required(dev);
+
+	reserved_chunks = ((reserved_blocks + checkpt_blocks) * dev->param.chunks_per_block);
+
+	return (dev->n_free_chunks > (reserved_chunks + n_chunks));
+}
+
+static int yaffs_alloc_chunk(yaffs_dev_t *dev, int use_reserver,
+		yaffs_block_info_t **block_ptr)
+{
+	int ret_val;
+	yaffs_block_info_t *bi;
+
+	if (dev->alloc_block < 0) {
+		/* Get next block to allocate off */
+		dev->alloc_block = yaffs_find_alloc_block(dev);
+		dev->alloc_page = 0;
+	}
+
+	if (!use_reserver && !yaffs_check_alloc_available(dev, 1)) {
+		/* Not enough space to allocate unless we're allowed to use the reserve. */
+		return -1;
+	}
+
+	if (dev->n_erased_blocks < dev->param.n_reserved_blocks
+			&& dev->alloc_page == 0) {
+		T(YAFFS_TRACE_ALLOCATE, (TSTR("Allocating reserve" TENDSTR)));
+	}
+
+	/* Next page please.... */
+	if (dev->alloc_block >= 0) {
+		bi = yaffs_get_block_info(dev, dev->alloc_block);
+
+		ret_val = (dev->alloc_block * dev->param.chunks_per_block) +
+			dev->alloc_page;
+		bi->pages_in_use++;
+		yaffs_set_chunk_bit(dev, dev->alloc_block,
+				dev->alloc_page);
+
+		dev->alloc_page++;
+
+		dev->n_free_chunks--;
+
+		/* If the block is full set the state to full */
+		if (dev->alloc_page >= dev->param.chunks_per_block) {
+			bi->block_state = YAFFS_BLOCK_STATE_FULL;
+			dev->alloc_block = -1;
+		}
+
+		if (block_ptr)
+			*block_ptr = bi;
+
+		return ret_val;
+	}
+
+	T(YAFFS_TRACE_ERROR,
+			(TSTR("!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!" TENDSTR)));
+
+	return -1;
+}
+
+static int yaffs_get_erased_chunks(yaffs_dev_t *dev)
+{
+	int n;
+
+	n = dev->n_erased_blocks * dev->param.chunks_per_block;
+
+	if (dev->alloc_block > 0)
+		n += (dev->param.chunks_per_block - dev->alloc_page);
+
+	return n;
+
+}
+
+/*
+ * yaffs_skip_rest_of_block() skips over the rest of the allocation block
+ * if we don't want to write to it.
+ */
+void yaffs_skip_rest_of_block(yaffs_dev_t *dev)
+{
+	if(dev->alloc_block > 0){
+		yaffs_block_info_t *bi = yaffs_get_block_info(dev, dev->alloc_block);
+		if(bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING){
+			bi->block_state = YAFFS_BLOCK_STATE_FULL;
+			dev->alloc_block = -1;
+		}
+	}
+}
+
+
+static int yaffs_gc_block(yaffs_dev_t *dev, int block,
+		int whole_block)
+{
+	int old_chunk;
+	int new_chunk;
+	int mark_flash;
+	int ret_val = YAFFS_OK;
+	int i;
+	int is_checkpt_block;
+	int matching_chunk;
+	int max_copies;
+
+	int chunks_before = yaffs_get_erased_chunks(dev);
+	int chunks_after;
+
+	yaffs_ext_tags tags;
+
+	yaffs_block_info_t *bi = yaffs_get_block_info(dev, block);
+
+	yaffs_obj_t *object;
+
+	is_checkpt_block = (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT);
+
+
+	T(YAFFS_TRACE_TRACING,
+			(TSTR("Collecting block %d, in use %d, shrink %d, whole_block %d" TENDSTR),
+			 block,
+			 bi->pages_in_use,
+			 bi->has_shrink_hdr,
+			 whole_block));
+
+	/*yaffs_verify_free_chunks(dev); */
+
+	if(bi->block_state == YAFFS_BLOCK_STATE_FULL)
+		bi->block_state = YAFFS_BLOCK_STATE_COLLECTING;
+	
+	bi->has_shrink_hdr = 0;	/* clear the flag so that the block can erase */
+
+	dev->gc_disable = 1;
+
+	if (is_checkpt_block ||
+			!yaffs_still_some_chunks(dev, block)) {
+		T(YAFFS_TRACE_TRACING,
+				(TSTR
+				 ("Collecting block %d that has no chunks in use" TENDSTR),
+				 block));
+		yaffs_block_became_dirty(dev, block);
+	} else {
+
+		__u8 *buffer = yaffs_get_temp_buffer(dev, __LINE__);
+
+		yaffs_verify_blk(dev, bi, block);
+
+		max_copies = (whole_block) ? dev->param.chunks_per_block : 5;
+		old_chunk = block * dev->param.chunks_per_block + dev->gc_chunk;
+
+		for (/* init already done */;
+		     ret_val == YAFFS_OK &&
+		     dev->gc_chunk < dev->param.chunks_per_block &&
+		     (bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) &&
+		     max_copies > 0;
+		     dev->gc_chunk++, old_chunk++) {
+			if (yaffs_check_chunk_bit(dev, block, dev->gc_chunk)) {
+
+				/* This page is in use and might need to be copied off */
+
+				max_copies--;
+
+				mark_flash = 1;
+
+				yaffs_init_tags(&tags);
+
+				yaffs_rd_chunk_tags_nand(dev, old_chunk,
+								buffer, &tags);
+
+				object =
+				    yaffs_find_by_number(dev,
+							     tags.obj_id);
+
+				T(YAFFS_TRACE_GC_DETAIL,
+				  (TSTR
+				   ("Collecting chunk in block %d, %d %d %d " TENDSTR),
+				   dev->gc_chunk, tags.obj_id, tags.chunk_id,
+				   tags.n_bytes));
+
+				if (object && !yaffs_skip_verification(dev)) {
+					if (tags.chunk_id == 0)
+						matching_chunk = object->hdr_chunk;
+					else if (object->soft_del)
+						matching_chunk = old_chunk; /* Defeat the test */
+					else
+						matching_chunk = yaffs_find_chunk_in_file(object, tags.chunk_id, NULL);
+
+					if (old_chunk != matching_chunk)
+						T(YAFFS_TRACE_ERROR,
+						  (TSTR("gc: page in gc mismatch: %d %d %d %d"TENDSTR),
+						  old_chunk, matching_chunk, tags.obj_id, tags.chunk_id));
+
+				}
+
+				if (!object) {
+					T(YAFFS_TRACE_ERROR,
+					  (TSTR
+					   ("page %d in gc has no object: %d %d %d "
+					    TENDSTR), old_chunk,
+					    tags.obj_id, tags.chunk_id, tags.n_bytes));
+				}
+
+				if (object &&
+				    object->deleted &&
+				    object->soft_del &&
+				    tags.chunk_id != 0) {
+					/* Data chunk in a soft deleted file, throw it away
+					 * It's a soft deleted data chunk,
+					 * No need to copy this, just forget about it and
+					 * fix up the object.
+					 */
+					 
+					/* Free chunks already includes softdeleted chunks.
+					 * How ever this chunk is going to soon be really deleted
+					 * which will increment free chunks.
+					 * We have to decrement free chunks so this works out properly.
+					 */
+					dev->n_free_chunks--;
+					bi->soft_del_pages--;
+
+					object->n_data_chunks--;
+
+					if (object->n_data_chunks <= 0) {
+						/* remeber to clean up the object */
+						dev->gc_cleanup_list[dev->n_clean_ups] =
+						    tags.obj_id;
+						dev->n_clean_ups++;
+					}
+					mark_flash = 0;
+				} else if (0) {
+					/* Todo object && object->deleted && object->n_data_chunks == 0 */
+					/* Deleted object header with no data chunks.
+					 * Can be discarded and the file deleted.
+					 */
+					object->hdr_chunk = 0;
+					yaffs_free_tnode(object->my_dev,
+							object->variant.
+							file_variant.top);
+					object->variant.file_variant.top = NULL;
+					yaffs_generic_obj_del(object);
+
+				} else if (object) {
+					/* It's either a data chunk in a live file or
+					 * an ObjectHeader, so we're interested in it.
+					 * NB Need to keep the ObjectHeaders of deleted files
+					 * until the whole file has been deleted off
+					 */
+					tags.serial_number++;
+
+					dev->n_gc_copies++;
+
+					if (tags.chunk_id == 0) {
+						/* It is an object Id,
+						 * We need to nuke the shrinkheader flags first
+						 * Also need to clean up shadowing.
+						 * We no longer want the shrink_header flag since its work is done
+						 * and if it is left in place it will mess up scanning.
+						 */
+
+						yaffs_obj_header *oh;
+						oh = (yaffs_obj_header *)buffer;
+
+						oh->is_shrink = 0;
+						tags.extra_is_shrink = 0;
+
+						oh->shadows_obj = 0;
+						oh->inband_shadowed_obj_id = 0;
+						tags.extra_shadows = 0;
+
+						/* Update file size */
+						if(object->variant_type == YAFFS_OBJECT_TYPE_FILE){
+							oh->file_size = object->variant.file_variant.file_size;
+							tags.extra_length = oh->file_size;
+						}
+
+						yaffs_verify_oh(object, oh, &tags, 1);
+						new_chunk =
+						    yaffs_write_new_chunk(dev,(__u8 *) oh, &tags, 1);
+					} else
+						new_chunk =
+						    yaffs_write_new_chunk(dev, buffer, &tags, 1);
+
+					if (new_chunk < 0) {
+						ret_val = YAFFS_FAIL;
+					} else {
+
+						/* Ok, now fix up the Tnodes etc. */
+
+						if (tags.chunk_id == 0) {
+							/* It's a header */
+							object->hdr_chunk =  new_chunk;
+							object->serial =   tags.serial_number;
+						} else {
+							/* It's a data chunk */
+							int ok;
+							ok = yaffs_put_chunk_in_file
+							    (object,
+							     tags.chunk_id,
+							     new_chunk, 0);
+						}
+					}
+				}
+
+				if (ret_val == YAFFS_OK)
+					yaffs_chunk_del(dev, old_chunk, mark_flash, __LINE__);
+
+			}
+		}
+
+		yaffs_release_temp_buffer(dev, buffer, __LINE__);
+
+
+
+	}
+
+	yaffs_verify_collected_blk(dev, bi, block);
+
+
+
+	if (bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) {
+		/*
+		 * The gc did not complete. Set block state back to FULL
+		 * because checkpointing does not restore gc.
+		 */
+		bi->block_state = YAFFS_BLOCK_STATE_FULL;
+	} else {
+		/* The gc completed. */
+		/* Do any required cleanups */
+		for (i = 0; i < dev->n_clean_ups; i++) {
+			/* Time to delete the file too */
+			object =
+			    yaffs_find_by_number(dev,
+						     dev->gc_cleanup_list[i]);
+			if (object) {
+				yaffs_free_tnode(dev,
+						object->variant.file_variant.
+						top);
+				object->variant.file_variant.top = NULL;
+				T(YAFFS_TRACE_GC,
+				  (TSTR
+				   ("yaffs: About to finally delete object %d"
+				    TENDSTR), object->obj_id));
+				yaffs_generic_obj_del(object);
+				object->my_dev->n_deleted_files--;
+			}
+
+		}
+
+
+		chunks_after = yaffs_get_erased_chunks(dev);
+		if (chunks_before >= chunks_after) {
+			T(YAFFS_TRACE_GC,
+			  (TSTR
+			   ("gc did not increase free chunks before %d after %d"
+			    TENDSTR), chunks_before, chunks_after));
+		}
+		dev->gc_block = 0;
+		dev->gc_chunk = 0;
+		dev->n_clean_ups = 0;
+	}
+
+	dev->gc_disable = 0;
+
+	return ret_val;
+}
+
+/*
+ * FindBlockForgarbageCollection is used to select the dirtiest block (or close enough)
+ * for garbage collection.
+ */
+
+static unsigned yaffs_find_gc_block(yaffs_dev_t *dev,
+					int aggressive,
+					int background)
+{
+	int i;
+	int iterations;
+	unsigned selected = 0;
+	int prioritised = 0;
+	int prioritised_exist = 0;
+	yaffs_block_info_t *bi;
+	int threshold;
+
+	/* First let's see if we need to grab a prioritised block */
+	if (dev->has_pending_prioritised_gc && !aggressive) {
+		dev->gc_dirtiest = 0;
+		bi = dev->block_info;
+		for (i = dev->internal_start_block;
+			i <= dev->internal_end_block && !selected;
+			i++) {
+
+			if (bi->gc_prioritise) {
+				prioritised_exist = 1;
+				if (bi->block_state == YAFFS_BLOCK_STATE_FULL &&
+				   yaffs_block_ok_for_gc(dev, bi)) {
+					selected = i;
+					prioritised = 1;
+				}
+			}
+			bi++;
+		}
+
+		/*
+		 * If there is a prioritised block and none was selected then
+		 * this happened because there is at least one old dirty block gumming
+		 * up the works. Let's gc the oldest dirty block.
+		 */
+
+		if(prioritised_exist &&
+			!selected &&
+			dev->oldest_dirty_block > 0)
+			selected = dev->oldest_dirty_block;
+
+		if (!prioritised_exist) /* None found, so we can clear this */
+			dev->has_pending_prioritised_gc = 0;
+	}
+
+	/* If we're doing aggressive GC then we are happy to take a less-dirty block, and
+	 * search harder.
+	 * else (we're doing a leasurely gc), then we only bother to do this if the
+	 * block has only a few pages in use.
+	 */
+
+	if (!selected){
+		int pages_used;
+		int n_blocks = dev->internal_end_block - dev->internal_start_block + 1;
+		if (aggressive){
+			threshold = dev->param.chunks_per_block;
+			iterations = n_blocks;
+		} else {
+			int max_threshold;
+
+			if(background)
+				max_threshold = dev->param.chunks_per_block/2;
+			else
+				max_threshold = dev->param.chunks_per_block/8;
+
+			if(max_threshold <  YAFFS_GC_PASSIVE_THRESHOLD)
+				max_threshold = YAFFS_GC_PASSIVE_THRESHOLD;
+
+			threshold = background ?
+				(dev->gc_not_done + 2) * 2 : 0;
+			if(threshold <YAFFS_GC_PASSIVE_THRESHOLD)
+				threshold = YAFFS_GC_PASSIVE_THRESHOLD;
+			if(threshold > max_threshold)
+				threshold = max_threshold;
+
+			iterations = n_blocks / 16 + 1;
+			if (iterations > 100)
+				iterations = 100;
+		}
+
+		for (i = 0;
+			i < iterations &&
+			(dev->gc_dirtiest < 1 ||
+				dev->gc_pages_in_use > YAFFS_GC_GOOD_ENOUGH);
+			i++) {
+			dev->gc_block_finder++;
+			if (dev->gc_block_finder < dev->internal_start_block ||
+				dev->gc_block_finder > dev->internal_end_block)
+				dev->gc_block_finder = dev->internal_start_block;
+
+			bi = yaffs_get_block_info(dev, dev->gc_block_finder);
+
+			pages_used = bi->pages_in_use - bi->soft_del_pages;
+
+			if (bi->block_state == YAFFS_BLOCK_STATE_FULL &&
+				pages_used < dev->param.chunks_per_block &&
+				(dev->gc_dirtiest < 1 || pages_used < dev->gc_pages_in_use) &&
+				yaffs_block_ok_for_gc(dev, bi)) {
+				dev->gc_dirtiest = dev->gc_block_finder;
+				dev->gc_pages_in_use = pages_used;
+			}
+		}
+
+		if(dev->gc_dirtiest > 0 && dev->gc_pages_in_use <= threshold)
+			selected = dev->gc_dirtiest;
+	}
+
+	/*
+	 * If nothing has been selected for a while, try selecting the oldest dirty
+	 * because that's gumming up the works.
+	 */
+
+	if(!selected && dev->param.is_yaffs2 &&
+		dev->gc_not_done >= ( background ? 10 : 20)){
+		yaffs2_find_oldest_dirty_seq(dev);
+		if(dev->oldest_dirty_block > 0) {
+			selected = dev->oldest_dirty_block;
+			dev->gc_dirtiest = selected;
+			dev->oldest_dirty_gc_count++;
+			bi = yaffs_get_block_info(dev, selected);
+			dev->gc_pages_in_use =  bi->pages_in_use - bi->soft_del_pages;
+		} else
+			dev->gc_not_done = 0;
+	}
+
+	if(selected){
+		T(YAFFS_TRACE_GC,
+		  (TSTR("GC Selected block %d with %d free, prioritised:%d" TENDSTR),
+		  selected,
+		  dev->param.chunks_per_block - dev->gc_pages_in_use,
+		  prioritised));
+
+		dev->n_gc_blocks++;
+		if(background)
+			dev->bg_gcs++;
+
+		dev->gc_dirtiest = 0;
+		dev->gc_pages_in_use = 0;
+		dev->gc_not_done = 0;
+		if(dev->refresh_skip > 0)
+			dev->refresh_skip--;
+	} else{
+		dev->gc_not_done++;
+		T(YAFFS_TRACE_GC,
+		  (TSTR("GC none: finder %d skip %d threshold %d dirtiest %d using %d oldest %d%s" TENDSTR),
+		  dev->gc_block_finder, dev->gc_not_done,
+		  threshold,
+		  dev->gc_dirtiest, dev->gc_pages_in_use,
+		  dev->oldest_dirty_block,
+		  background ? " bg" : ""));
+	}
+
+	return selected;
+}
+
+/* New garbage collector
+ * If we're very low on erased blocks then we do aggressive garbage collection
+ * otherwise we do "leasurely" garbage collection.
+ * Aggressive gc looks further (whole array) and will accept less dirty blocks.
+ * Passive gc only inspects smaller areas and will only accept more dirty blocks.
+ *
+ * The idea is to help clear out space in a more spread-out manner.
+ * Dunno if it really does anything useful.
+ */
+static int yaffs_check_gc(yaffs_dev_t *dev, int background)
+{
+	int aggressive = 0;
+	int gc_ok = YAFFS_OK;
+	int max_tries = 0;
+	int min_erased;
+	int erased_chunks;
+	int checkpt_block_adjust;
+
+	if(dev->param.gc_control &&
+		(dev->param.gc_control(dev) & 1) == 0)
+		return YAFFS_OK;
+
+	if (dev->gc_disable) {
+		/* Bail out so we don't get recursive gc */
+		return YAFFS_OK;
+	}
+
+	/* This loop should pass the first time.
+	 * We'll only see looping here if the collection does not increase space.
+	 */
+
+	do {
+		max_tries++;
+
+		checkpt_block_adjust = yaffs_calc_checkpt_blocks_required(dev);
+
+		min_erased  = dev->param.n_reserved_blocks + checkpt_block_adjust + 1;
+		erased_chunks = dev->n_erased_blocks * dev->param.chunks_per_block;
+
+		/* If we need a block soon then do aggressive gc.*/
+		if (dev->n_erased_blocks < min_erased)
+			aggressive = 1;
+		else {
+			if(!background && erased_chunks > (dev->n_free_chunks / 4))
+				break;
+
+			if(dev->gc_skip > 20)
+				dev->gc_skip = 20;
+			if(erased_chunks < dev->n_free_chunks/2 ||
+				dev->gc_skip < 1 ||
+				background)
+				aggressive = 0;
+			else {
+				dev->gc_skip--;
+				break;
+			}
+		}
+
+		dev->gc_skip = 5;
+
+                /* If we don't already have a block being gc'd then see if we should start another */
+
+		if (dev->gc_block < 1 && !aggressive) {
+			dev->gc_block = yaffs2_find_refresh_block(dev);
+			dev->gc_chunk = 0;
+			dev->n_clean_ups=0;
+		}
+		if (dev->gc_block < 1) {
+			dev->gc_block = yaffs_find_gc_block(dev, aggressive, background);
+			dev->gc_chunk = 0;
+			dev->n_clean_ups=0;
+		}
+
+		if (dev->gc_block > 0) {
+			dev->all_gcs++;
+			if (!aggressive)
+				dev->passive_gc_count++;
+
+			T(YAFFS_TRACE_GC,
+			  (TSTR
+			   ("yaffs: GC n_erased_blocks %d aggressive %d" TENDSTR),
+			   dev->n_erased_blocks, aggressive));
+
+			gc_ok = yaffs_gc_block(dev, dev->gc_block, aggressive);
+		}
+
+		if (dev->n_erased_blocks < (dev->param.n_reserved_blocks) && dev->gc_block > 0) {
+			T(YAFFS_TRACE_GC,
+			  (TSTR
+			   ("yaffs: GC !!!no reclaim!!! n_erased_blocks %d after try %d block %d"
+			    TENDSTR), dev->n_erased_blocks, max_tries, dev->gc_block));
+		}
+	} while ((dev->n_erased_blocks < dev->param.n_reserved_blocks) &&
+		 (dev->gc_block > 0) &&
+		 (max_tries < 2));
+
+	return aggressive ? gc_ok : YAFFS_OK;
+}
+
+/*
+ * yaffs_bg_gc()
+ * Garbage collects. Intended to be called from a background thread.
+ * Returns non-zero if at least half the free chunks are erased.
+ */
+int yaffs_bg_gc(yaffs_dev_t *dev, unsigned urgency)
+{
+	int erased_chunks = dev->n_erased_blocks * dev->param.chunks_per_block;
+
+	T(YAFFS_TRACE_BACKGROUND, (TSTR("Background gc %u" TENDSTR),urgency));
+
+	yaffs_check_gc(dev, 1);
+	return erased_chunks > dev->n_free_chunks/2;
+}
+
+/*-------------------------  TAGS --------------------------------*/
+
+static int yaffs_tags_match(const yaffs_ext_tags *tags, int obj_id,
+			   int chunk_obj)
+{
+	return (tags->chunk_id == chunk_obj &&
+		tags->obj_id == obj_id && !tags->is_deleted) ? 1 : 0;
+
+}
+
+
+/*-------------------- Data file manipulation -----------------*/
+
+static int yaffs_find_chunk_in_file(yaffs_obj_t *in, int inode_chunk,
+				 yaffs_ext_tags *tags)
+{
+	/*Get the Tnode, then get the level 0 offset chunk offset */
+	yaffs_tnode_t *tn;
+	int the_chunk = -1;
+	yaffs_ext_tags local_tags;
+	int ret_val = -1;
+
+	yaffs_dev_t *dev = in->my_dev;
+
+	if (!tags) {
+		/* Passed a NULL, so use our own tags space */
+		tags = &local_tags;
+	}
+
+	tn = yaffs_find_tnode_0(dev, &in->variant.file_variant, inode_chunk);
+
+	if (tn) {
+		the_chunk = yaffs_get_group_base(dev, tn, inode_chunk);
+
+		ret_val =
+		    yaffs_find_chunk_in_group(dev, the_chunk, tags, in->obj_id,
+					   inode_chunk);
+	}
+	return ret_val;
+}
+
+static int yaffs_find_del_file_chunk(yaffs_obj_t *in, int inode_chunk,
+					  yaffs_ext_tags *tags)
+{
+	/* Get the Tnode, then get the level 0 offset chunk offset */
+	yaffs_tnode_t *tn;
+	int the_chunk = -1;
+	yaffs_ext_tags local_tags;
+
+	yaffs_dev_t *dev = in->my_dev;
+	int ret_val = -1;
+
+	if (!tags) {
+		/* Passed a NULL, so use our own tags space */
+		tags = &local_tags;
+	}
+
+	tn = yaffs_find_tnode_0(dev, &in->variant.file_variant, inode_chunk);
+
+	if (tn) {
+
+		the_chunk = yaffs_get_group_base(dev, tn, inode_chunk);
+
+		ret_val =
+		    yaffs_find_chunk_in_group(dev, the_chunk, tags, in->obj_id,
+					   inode_chunk);
+
+		/* Delete the entry in the filestructure (if found) */
+		if (ret_val != -1)
+			yaffs_load_tnode_0(dev, tn, inode_chunk, 0);
+	}
+
+	return ret_val;
+}
+
+
+int yaffs_put_chunk_in_file(yaffs_obj_t *in, int inode_chunk,
+			        int nand_chunk, int in_scan)
+{
+	/* NB in_scan is zero unless scanning.
+	 * For forward scanning, in_scan is > 0;
+	 * for backward scanning in_scan is < 0
+	 *
+	 * nand_chunk = 0 is a dummy insert to make sure the tnodes are there.
+	 */
+
+	yaffs_tnode_t *tn;
+	yaffs_dev_t *dev = in->my_dev;
+	int existing_cunk;
+	yaffs_ext_tags existing_tags;
+	yaffs_ext_tags new_tags;
+	unsigned existing_serial, new_serial;
+
+	if (in->variant_type != YAFFS_OBJECT_TYPE_FILE) {
+		/* Just ignore an attempt at putting a chunk into a non-file during scanning
+		 * If it is not during Scanning then something went wrong!
+		 */
+		if (!in_scan) {
+			T(YAFFS_TRACE_ERROR,
+			  (TSTR
+			   ("yaffs tragedy:attempt to put data chunk into a non-file"
+			    TENDSTR)));
+			YBUG();
+		}
+
+		yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
+		return YAFFS_OK;
+	}
+
+	tn = yaffs_add_find_tnode_0(dev,
+					&in->variant.file_variant,
+					inode_chunk,
+					NULL);
+	if (!tn)
+		return YAFFS_FAIL;
+	
+	if(!nand_chunk)
+		/* Dummy insert, bail now */
+		return YAFFS_OK;
+
+	existing_cunk = yaffs_get_group_base(dev, tn, inode_chunk);
+
+	if (in_scan != 0) {
+		/* If we're scanning then we need to test for duplicates
+		 * NB This does not need to be efficient since it should only ever
+		 * happen when the power fails during a write, then only one
+		 * chunk should ever be affected.
+		 *
+		 * Correction for YAFFS2: This could happen quite a lot and we need to think about efficiency! TODO
+		 * Update: For backward scanning we don't need to re-read tags so this is quite cheap.
+		 */
+
+		if (existing_cunk > 0) {
+			/* NB Right now existing chunk will not be real chunk_id if the chunk group size > 1
+			 *    thus we have to do a FindChunkInFile to get the real chunk id.
+			 *
+			 * We have a duplicate now we need to decide which one to use:
+			 *
+			 * Backwards scanning YAFFS2: The old one is what we use, dump the new one.
+			 * Forward scanning YAFFS2: The new one is what we use, dump the old one.
+			 * YAFFS1: Get both sets of tags and compare serial numbers.
+			 */
+
+			if (in_scan > 0) {
+				/* Only do this for forward scanning */
+				yaffs_rd_chunk_tags_nand(dev,
+								nand_chunk,
+								NULL, &new_tags);
+
+				/* Do a proper find */
+				existing_cunk =
+				    yaffs_find_chunk_in_file(in, inode_chunk,
+							  &existing_tags);
+			}
+
+			if (existing_cunk <= 0) {
+				/*Hoosterman - how did this happen? */
+
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("yaffs tragedy: existing chunk < 0 in scan"
+				    TENDSTR)));
+
+			}
+
+			/* NB The deleted flags should be false, otherwise the chunks will
+			 * not be loaded during a scan
+			 */
+
+			if (in_scan > 0) {
+				new_serial = new_tags.serial_number;
+				existing_serial = existing_tags.serial_number;
+			}
+
+			if ((in_scan > 0) &&
+			    (existing_cunk <= 0 ||
+			     ((existing_serial + 1) & 3) == new_serial)) {
+				/* Forward scanning.
+				 * Use new
+				 * Delete the old one and drop through to update the tnode
+				 */
+				yaffs_chunk_del(dev, existing_cunk, 1,
+						  __LINE__);
+			} else {
+				/* Backward scanning or we want to use the existing one
+				 * Use existing.
+				 * Delete the new one and return early so that the tnode isn't changed
+				 */
+				yaffs_chunk_del(dev, nand_chunk, 1,
+						  __LINE__);
+				return YAFFS_OK;
+			}
+		}
+
+	}
+
+	if (existing_cunk == 0)
+		in->n_data_chunks++;
+
+	yaffs_load_tnode_0(dev, tn, inode_chunk, nand_chunk);
+
+	return YAFFS_OK;
+}
+
+static int yaffs_rd_data_obj(yaffs_obj_t *in, int inode_chunk,
+					__u8 *buffer)
+{
+	int nand_chunk = yaffs_find_chunk_in_file(in, inode_chunk, NULL);
+
+	if (nand_chunk >= 0)
+		return yaffs_rd_chunk_tags_nand(in->my_dev, nand_chunk,
+						buffer, NULL);
+	else {
+		T(YAFFS_TRACE_NANDACCESS,
+		  (TSTR("Chunk %d not found zero instead" TENDSTR),
+		   nand_chunk));
+		/* get sane (zero) data if you read a hole */
+		memset(buffer, 0, in->my_dev->data_bytes_per_chunk);
+		return 0;
+	}
+
+}
+
+void yaffs_chunk_del(yaffs_dev_t *dev, int chunk_id, int mark_flash, int lyn)
+{
+	int block;
+	int page;
+	yaffs_ext_tags tags;
+	yaffs_block_info_t *bi;
+
+	if (chunk_id <= 0)
+		return;
+
+	dev->n_deletions++;
+	block = chunk_id / dev->param.chunks_per_block;
+	page = chunk_id % dev->param.chunks_per_block;
+
+
+	if (!yaffs_check_chunk_bit(dev, block, page))
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Deleting invalid chunk %d"TENDSTR),
+			 chunk_id));
+
+	bi = yaffs_get_block_info(dev, block);
+	
+	yaffs2_update_oldest_dirty_seq(dev, block, bi);
+
+	T(YAFFS_TRACE_DELETION,
+	  (TSTR("line %d delete of chunk %d" TENDSTR), lyn, chunk_id));
+
+	if (!dev->param.is_yaffs2 && mark_flash &&
+	    bi->block_state != YAFFS_BLOCK_STATE_COLLECTING) {
+
+		yaffs_init_tags(&tags);
+
+		tags.is_deleted = 1;
+
+		yaffs_wr_chunk_tags_nand(dev, chunk_id, NULL, &tags);
+		yaffs_handle_chunk_update(dev, chunk_id, &tags);
+	} else {
+		dev->n_unmarked_deletions++;
+	}
+
+	/* Pull out of the management area.
+	 * If the whole block became dirty, this will kick off an erasure.
+	 */
+	if (bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING ||
+	    bi->block_state == YAFFS_BLOCK_STATE_FULL ||
+	    bi->block_state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
+	    bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) {
+		dev->n_free_chunks++;
+
+		yaffs_clear_chunk_bit(dev, block, page);
+
+		bi->pages_in_use--;
+
+		if (bi->pages_in_use == 0 &&
+		    !bi->has_shrink_hdr &&
+		    bi->block_state != YAFFS_BLOCK_STATE_ALLOCATING &&
+		    bi->block_state != YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
+			yaffs_block_became_dirty(dev, block);
+		}
+
+	}
+
+}
+
+static int yaffs_wr_data_obj(yaffs_obj_t *in, int inode_chunk,
+					const __u8 *buffer, int n_bytes,
+					int use_reserve)
+{
+	/* Find old chunk Need to do this to get serial number
+	 * Write new one and patch into tree.
+	 * Invalidate old tags.
+	 */
+
+	int prev_chunk_id;
+	yaffs_ext_tags prev_tags;
+
+	int new_chunk_id;
+	yaffs_ext_tags new_tags;
+
+	yaffs_dev_t *dev = in->my_dev;
+
+	yaffs_check_gc(dev,0);
+
+	/* Get the previous chunk at this location in the file if it exists.
+	 * If it does not exist then put a zero into the tree. This creates
+	 * the tnode now, rather than later when it is harder to clean up.
+	 */
+	prev_chunk_id = yaffs_find_chunk_in_file(in, inode_chunk, &prev_tags);
+	if(prev_chunk_id < 1 &&
+		!yaffs_put_chunk_in_file(in, inode_chunk, 0, 0))
+		return 0;
+
+	/* Set up new tags */
+	yaffs_init_tags(&new_tags);
+
+	new_tags.chunk_id = inode_chunk;
+	new_tags.obj_id = in->obj_id;
+	new_tags.serial_number =
+	    (prev_chunk_id > 0) ? prev_tags.serial_number + 1 : 1;
+	new_tags.n_bytes = n_bytes;
+
+	if (n_bytes < 1 || n_bytes > dev->param.total_bytes_per_chunk) {
+		T(YAFFS_TRACE_ERROR,
+		(TSTR("Writing %d bytes to chunk!!!!!!!!!" TENDSTR), n_bytes));
+		YBUG();
+	}
+	
+		
+	new_chunk_id =
+	    yaffs_write_new_chunk(dev, buffer, &new_tags,
+					      use_reserve);
+
+	if (new_chunk_id > 0) {
+		yaffs_put_chunk_in_file(in, inode_chunk, new_chunk_id, 0);
+
+		if (prev_chunk_id > 0)
+			yaffs_chunk_del(dev, prev_chunk_id, 1, __LINE__);
+
+		yaffs_verify_file_sane(in);
+	}
+	return new_chunk_id;
+
+}
+
+/* UpdateObjectHeader updates the header on NAND for an object.
+ * If name is not NULL, then that new name is used.
+ */
+int yaffs_update_oh(yaffs_obj_t *in, const YCHAR *name, int force,
+			     int is_shrink, int shadows, yaffs_xattr_mod *xmod)
+{
+
+	yaffs_block_info_t *bi;
+
+	yaffs_dev_t *dev = in->my_dev;
+
+	int prev_chunk_id;
+	int ret_val = 0;
+	int result = 0;
+
+	int new_chunk_id;
+	yaffs_ext_tags new_tags;
+	yaffs_ext_tags old_tags;
+	const YCHAR *alias = NULL;
+
+	__u8 *buffer = NULL;
+	YCHAR old_name[YAFFS_MAX_NAME_LENGTH + 1];
+
+	yaffs_obj_header *oh = NULL;
+
+	yaffs_strcpy(old_name, _Y("silly old name"));
+
+
+	if (!in->fake ||
+		in == dev->root_dir || /* The root_dir should also be saved */
+		force  || xmod) {
+
+		yaffs_check_gc(dev,0);
+		yaffs_check_obj_details_loaded(in);
+
+		buffer = yaffs_get_temp_buffer(in->my_dev, __LINE__);
+		oh = (yaffs_obj_header *) buffer;
+
+		prev_chunk_id = in->hdr_chunk;
+
+		if (prev_chunk_id > 0) {
+			result = yaffs_rd_chunk_tags_nand(dev, prev_chunk_id,
+							buffer, &old_tags);
+
+			yaffs_verify_oh(in, oh, &old_tags, 0);
+
+			memcpy(old_name, oh->name, sizeof(oh->name));
+			memset(buffer, 0xFF, sizeof(yaffs_obj_header));
+		} else
+			memset(buffer, 0xFF, dev->data_bytes_per_chunk);
+
+		oh->type = in->variant_type;
+		oh->yst_mode = in->yst_mode;
+		oh->shadows_obj = oh->inband_shadowed_obj_id = shadows;
+
+#ifdef CONFIG_YAFFS_WINCE
+		oh->win_atime[0] = in->win_atime[0];
+		oh->win_ctime[0] = in->win_ctime[0];
+		oh->win_mtime[0] = in->win_mtime[0];
+		oh->win_atime[1] = in->win_atime[1];
+		oh->win_ctime[1] = in->win_ctime[1];
+		oh->win_mtime[1] = in->win_mtime[1];
+#else
+		oh->yst_uid = in->yst_uid;
+		oh->yst_gid = in->yst_gid;
+		oh->yst_atime = in->yst_atime;
+		oh->yst_mtime = in->yst_mtime;
+		oh->yst_ctime = in->yst_ctime;
+		oh->yst_rdev = in->yst_rdev;
+#endif
+		if (in->parent)
+			oh->parent_obj_id = in->parent->obj_id;
+		else
+			oh->parent_obj_id = 0;
+
+		if (name && *name) {
+			memset(oh->name, 0, sizeof(oh->name));
+			yaffs_load_oh_from_name(dev,oh->name,name);
+		} else if (prev_chunk_id > 0)
+			memcpy(oh->name, old_name, sizeof(oh->name));
+		else
+			memset(oh->name, 0, sizeof(oh->name));
+
+		oh->is_shrink = is_shrink;
+
+		switch (in->variant_type) {
+		case YAFFS_OBJECT_TYPE_UNKNOWN:
+			/* Should not happen */
+			break;
+		case YAFFS_OBJECT_TYPE_FILE:
+			oh->file_size =
+			    (oh->parent_obj_id == YAFFS_OBJECTID_DELETED
+			     || oh->parent_obj_id ==
+			     YAFFS_OBJECTID_UNLINKED) ? 0 : in->variant.
+			    file_variant.file_size;
+			break;
+		case YAFFS_OBJECT_TYPE_HARDLINK:
+			oh->equiv_id =
+			    in->variant.hardlink_variant.equiv_id;
+			break;
+		case YAFFS_OBJECT_TYPE_SPECIAL:
+			/* Do nothing */
+			break;
+		case YAFFS_OBJECT_TYPE_DIRECTORY:
+			/* Do nothing */
+			break;
+		case YAFFS_OBJECT_TYPE_SYMLINK:
+			alias = in->variant.symlink_variant.alias;
+			if(!alias)
+				alias = _Y("no alias");
+			yaffs_strncpy(oh->alias,
+					alias,
+				      YAFFS_MAX_ALIAS_LENGTH);
+			oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
+			break;
+		}
+
+		/* process any xattrib modifications */
+		if(xmod)
+			yaffs_apply_xattrib_mod(in, (char *)buffer, xmod);
+
+
+		/* Tags */
+		yaffs_init_tags(&new_tags);
+		in->serial++;
+		new_tags.chunk_id = 0;
+		new_tags.obj_id = in->obj_id;
+		new_tags.serial_number = in->serial;
+
+		/* Add extra info for file header */
+
+		new_tags.extra_available = 1;
+		new_tags.extra_parent_id = oh->parent_obj_id;
+		new_tags.extra_length = oh->file_size;
+		new_tags.extra_is_shrink = oh->is_shrink;
+		new_tags.extra_equiv_id = oh->equiv_id;
+		new_tags.extra_shadows = (oh->shadows_obj > 0) ? 1 : 0;
+		new_tags.extra_obj_type = in->variant_type;
+
+		yaffs_verify_oh(in, oh, &new_tags, 1);
+
+		/* Create new chunk in NAND */
+		new_chunk_id =
+		    yaffs_write_new_chunk(dev, buffer, &new_tags,
+						      (prev_chunk_id > 0) ? 1 : 0);
+
+		if (new_chunk_id >= 0) {
+
+			in->hdr_chunk = new_chunk_id;
+
+			if (prev_chunk_id > 0) {
+				yaffs_chunk_del(dev, prev_chunk_id, 1,
+						  __LINE__);
+			}
+
+			if (!yaffs_obj_cache_dirty(in))
+				in->dirty = 0;
+
+			/* If this was a shrink, then mark the block that the chunk lives on */
+			if (is_shrink) {
+				bi = yaffs_get_block_info(in->my_dev,
+					new_chunk_id / in->my_dev->param.chunks_per_block);
+				bi->has_shrink_hdr = 1;
+			}
+
+		}
+
+		ret_val = new_chunk_id;
+
+	}
+
+	if (buffer)
+		yaffs_release_temp_buffer(dev, buffer, __LINE__);
+
+	return ret_val;
+}
+
+/*------------------------ Short Operations Cache ----------------------------------------
+ *   In many situations where there is no high level buffering (eg WinCE) a lot of
+ *   reads might be short sequential reads, and a lot of writes may be short
+ *   sequential writes. eg. scanning/writing a jpeg file.
+ *   In these cases, a short read/write cache can provide a huge perfomance benefit
+ *   with dumb-as-a-rock code.
+ *   In Linux, the page cache provides read buffering aand the short op cache provides write
+ *   buffering.
+ *
+ *   There are a limited number (~10) of cache chunks per device so that we don't
+ *   need a very intelligent search.
+ */
+
+static int yaffs_obj_cache_dirty(yaffs_obj_t *obj)
+{
+	yaffs_dev_t *dev = obj->my_dev;
+	int i;
+	yaffs_cache_t *cache;
+	int n_caches = obj->my_dev->param.n_caches;
+
+	for (i = 0; i < n_caches; i++) {
+		cache = &dev->cache[i];
+		if (cache->object == obj &&
+		    cache->dirty)
+			return 1;
+	}
+
+	return 0;
+}
+
+
+static void yaffs_flush_file_cache(yaffs_obj_t *obj)
+{
+	yaffs_dev_t *dev = obj->my_dev;
+	int lowest = -99;	/* Stop compiler whining. */
+	int i;
+	yaffs_cache_t *cache;
+	int chunk_written = 0;
+	int n_caches = obj->my_dev->param.n_caches;
+
+	if (n_caches > 0) {
+		do {
+			cache = NULL;
+
+			/* Find the dirty cache for this object with the lowest chunk id. */
+			for (i = 0; i < n_caches; i++) {
+				if (dev->cache[i].object == obj &&
+				    dev->cache[i].dirty) {
+					if (!cache
+					    || dev->cache[i].chunk_id <
+					    lowest) {
+						cache = &dev->cache[i];
+						lowest = cache->chunk_id;
+					}
+				}
+			}
+
+			if (cache && !cache->locked) {
+				/* Write it out and free it up */
+
+				chunk_written =
+				    yaffs_wr_data_obj(cache->object,
+								 cache->chunk_id,
+								 cache->data,
+								 cache->n_bytes,
+								 1);
+				cache->dirty = 0;
+				cache->object = NULL;
+			}
+
+		} while (cache && chunk_written > 0);
+
+		if (cache) {
+			/* Hoosterman, disk full while writing cache out. */
+			T(YAFFS_TRACE_ERROR,
+			  (TSTR("yaffs tragedy: no space during cache write" TENDSTR)));
+
+		}
+	}
+
+}
+
+/*yaffs_flush_whole_cache(dev)
+ *
+ *
+ */
+
+void yaffs_flush_whole_cache(yaffs_dev_t *dev)
+{
+	yaffs_obj_t *obj;
+	int n_caches = dev->param.n_caches;
+	int i;
+
+	/* Find a dirty object in the cache and flush it...
+	 * until there are no further dirty objects.
+	 */
+	do {
+		obj = NULL;
+		for (i = 0; i < n_caches && !obj; i++) {
+			if (dev->cache[i].object &&
+			    dev->cache[i].dirty)
+				obj = dev->cache[i].object;
+
+		}
+		if (obj)
+			yaffs_flush_file_cache(obj);
+
+	} while (obj);
+
+}
+
+
+/* Grab us a cache chunk for use.
+ * First look for an empty one.
+ * Then look for the least recently used non-dirty one.
+ * Then look for the least recently used dirty one...., flush and look again.
+ */
+static yaffs_cache_t *yaffs_grab_chunk_worker(yaffs_dev_t *dev)
+{
+	int i;
+
+	if (dev->param.n_caches > 0) {
+		for (i = 0; i < dev->param.n_caches; i++) {
+			if (!dev->cache[i].object)
+				return &dev->cache[i];
+		}
+	}
+
+	return NULL;
+}
+
+static yaffs_cache_t *yaffs_grab_chunk_cache(yaffs_dev_t *dev)
+{
+	yaffs_cache_t *cache;
+	yaffs_obj_t *the_obj;
+	int usage;
+	int i;
+	int pushout;
+
+	if (dev->param.n_caches > 0) {
+		/* Try find a non-dirty one... */
+
+		cache = yaffs_grab_chunk_worker(dev);
+
+		if (!cache) {
+			/* They were all dirty, find the last recently used object and flush
+			 * its cache, then  find again.
+			 * NB what's here is not very accurate, we actually flush the object
+			 * the last recently used page.
+			 */
+
+			/* With locking we can't assume we can use entry zero */
+
+			the_obj = NULL;
+			usage = -1;
+			cache = NULL;
+			pushout = -1;
+
+			for (i = 0; i < dev->param.n_caches; i++) {
+				if (dev->cache[i].object &&
+				    !dev->cache[i].locked &&
+				    (dev->cache[i].last_use < usage || !cache)) {
+					usage = dev->cache[i].last_use;
+					the_obj = dev->cache[i].object;
+					cache = &dev->cache[i];
+					pushout = i;
+				}
+			}
+
+			if (!cache || cache->dirty) {
+				/* Flush and try again */
+				yaffs_flush_file_cache(the_obj);
+				cache = yaffs_grab_chunk_worker(dev);
+			}
+
+		}
+		return cache;
+	} else
+		return NULL;
+
+}
+
+/* Find a cached chunk */
+static yaffs_cache_t *yaffs_find_chunk_cache(const yaffs_obj_t *obj,
+					      int chunk_id)
+{
+	yaffs_dev_t *dev = obj->my_dev;
+	int i;
+	if (dev->param.n_caches > 0) {
+		for (i = 0; i < dev->param.n_caches; i++) {
+			if (dev->cache[i].object == obj &&
+			    dev->cache[i].chunk_id == chunk_id) {
+				dev->cache_hits++;
+
+				return &dev->cache[i];
+			}
+		}
+	}
+	return NULL;
+}
+
+/* Mark the chunk for the least recently used algorithym */
+static void yaffs_use_cache(yaffs_dev_t *dev, yaffs_cache_t *cache,
+				int is_write)
+{
+
+	if (dev->param.n_caches > 0) {
+		if (dev->cache_last_use < 0 || dev->cache_last_use > 100000000) {
+			/* Reset the cache usages */
+			int i;
+			for (i = 1; i < dev->param.n_caches; i++)
+				dev->cache[i].last_use = 0;
+
+			dev->cache_last_use = 0;
+		}
+
+		dev->cache_last_use++;
+
+		cache->last_use = dev->cache_last_use;
+
+		if (is_write)
+			cache->dirty = 1;
+	}
+}
+
+/* Invalidate a single cache page.
+ * Do this when a whole page gets written,
+ * ie the short cache for this page is no longer valid.
+ */
+static void yaffs_invalidate_chunk_cache(yaffs_obj_t *object, int chunk_id)
+{
+	if (object->my_dev->param.n_caches > 0) {
+		yaffs_cache_t *cache = yaffs_find_chunk_cache(object, chunk_id);
+
+		if (cache)
+			cache->object = NULL;
+	}
+}
+
+/* Invalidate all the cache pages associated with this object
+ * Do this whenever ther file is deleted or resized.
+ */
+static void yaffs_invalidate_whole_cache(yaffs_obj_t *in)
+{
+	int i;
+	yaffs_dev_t *dev = in->my_dev;
+
+	if (dev->param.n_caches > 0) {
+		/* Invalidate it. */
+		for (i = 0; i < dev->param.n_caches; i++) {
+			if (dev->cache[i].object == in)
+				dev->cache[i].object = NULL;
+		}
+	}
+}
+
+
+/*--------------------- File read/write ------------------------
+ * Read and write have very similar structures.
+ * In general the read/write has three parts to it
+ * An incomplete chunk to start with (if the read/write is not chunk-aligned)
+ * Some complete chunks
+ * An incomplete chunk to end off with
+ *
+ * Curve-balls: the first chunk might also be the last chunk.
+ */
+
+int yaffs_file_rd(yaffs_obj_t *in, __u8 *buffer, loff_t offset,
+			int n_bytes)
+{
+
+	int chunk;
+	__u32 start;
+	int n_copy;
+	int n = n_bytes;
+	int n_done = 0;
+	yaffs_cache_t *cache;
+
+	yaffs_dev_t *dev;
+
+	dev = in->my_dev;
+
+	while (n > 0) {
+		/* chunk = offset / dev->data_bytes_per_chunk + 1; */
+		/* start = offset % dev->data_bytes_per_chunk; */
+		yaffs_addr_to_chunk(dev, offset, &chunk, &start);
+		chunk++;
+
+		/* OK now check for the curveball where the start and end are in
+		 * the same chunk.
+		 */
+		if ((start + n) < dev->data_bytes_per_chunk)
+			n_copy = n;
+		else
+			n_copy = dev->data_bytes_per_chunk - start;
+
+		cache = yaffs_find_chunk_cache(in, chunk);
+
+		/* If the chunk is already in the cache or it is less than a whole chunk
+		 * or we're using inband tags then use the cache (if there is caching)
+		 * else bypass the cache.
+		 */
+		if (cache || n_copy != dev->data_bytes_per_chunk || dev->param.inband_tags) {
+			if (dev->param.n_caches > 0) {
+
+				/* If we can't find the data in the cache, then load it up. */
+
+				if (!cache) {
+					cache = yaffs_grab_chunk_cache(in->my_dev);
+					cache->object = in;
+					cache->chunk_id = chunk;
+					cache->dirty = 0;
+					cache->locked = 0;
+					yaffs_rd_data_obj(in, chunk,
+								      cache->
+								      data);
+					cache->n_bytes = 0;
+				}
+
+				yaffs_use_cache(dev, cache, 0);
+
+				cache->locked = 1;
+
+
+				memcpy(buffer, &cache->data[start], n_copy);
+
+				cache->locked = 0;
+			} else {
+				/* Read into the local buffer then copy..*/
+
+				__u8 *local_buffer =
+				    yaffs_get_temp_buffer(dev, __LINE__);
+				yaffs_rd_data_obj(in, chunk,
+							      local_buffer);
+
+				memcpy(buffer, &local_buffer[start], n_copy);
+
+
+				yaffs_release_temp_buffer(dev, local_buffer,
+							__LINE__);
+			}
+
+		} else {
+
+			/* A full chunk. Read directly into the supplied buffer. */
+			yaffs_rd_data_obj(in, chunk, buffer);
+
+		}
+
+		n -= n_copy;
+		offset += n_copy;
+		buffer += n_copy;
+		n_done += n_copy;
+
+	}
+
+	return n_done;
+}
+
+int yaffs_do_file_wr(yaffs_obj_t *in, const __u8 *buffer, loff_t offset,
+			int n_bytes, int write_trhrough)
+{
+
+	int chunk;
+	__u32 start;
+	int n_copy;
+	int n = n_bytes;
+	int n_done = 0;
+	int n_writeback;
+	int start_write = offset;
+	int chunk_written = 0;
+	__u32 n_bytes_read;
+	__u32 chunk_start;
+
+	yaffs_dev_t *dev;
+
+	dev = in->my_dev;
+
+	while (n > 0 && chunk_written >= 0) {
+		yaffs_addr_to_chunk(dev, offset, &chunk, &start);
+
+		if (chunk * dev->data_bytes_per_chunk + start != offset ||
+				start >= dev->data_bytes_per_chunk) {
+			T(YAFFS_TRACE_ERROR, (
+			   TSTR("AddrToChunk of offset %d gives chunk %d start %d"
+			   TENDSTR),
+			   (int)offset, chunk, start));
+		}
+		chunk++; /* File pos to chunk in file offset */
+
+		/* OK now check for the curveball where the start and end are in
+		 * the same chunk.
+		 */
+
+		if ((start + n) < dev->data_bytes_per_chunk) {
+			n_copy = n;
+
+			/* Now folks, to calculate how many bytes to write back....
+			 * If we're overwriting and not writing to then end of file then
+			 * we need to write back as much as was there before.
+			 */
+
+			chunk_start = ((chunk - 1) * dev->data_bytes_per_chunk);
+
+			if (chunk_start > in->variant.file_variant.file_size)
+				n_bytes_read = 0; /* Past end of file */
+			else
+				n_bytes_read = in->variant.file_variant.file_size - chunk_start;
+
+			if (n_bytes_read > dev->data_bytes_per_chunk)
+				n_bytes_read = dev->data_bytes_per_chunk;
+
+			n_writeback =
+			    (n_bytes_read >
+			     (start + n)) ? n_bytes_read : (start + n);
+
+			if (n_writeback < 0 || n_writeback > dev->data_bytes_per_chunk)
+				YBUG();
+
+		} else {
+			n_copy = dev->data_bytes_per_chunk - start;
+			n_writeback = dev->data_bytes_per_chunk;
+		}
+
+		if (n_copy != dev->data_bytes_per_chunk || dev->param.inband_tags) {
+			/* An incomplete start or end chunk (or maybe both start and end chunk),
+			 * or we're using inband tags, so we want to use the cache buffers.
+			 */
+			if (dev->param.n_caches > 0) {
+				yaffs_cache_t *cache;
+				/* If we can't find the data in the cache, then load the cache */
+				cache = yaffs_find_chunk_cache(in, chunk);
+
+				if (!cache
+				    && yaffs_check_alloc_available(dev, 1)) {
+					cache = yaffs_grab_chunk_cache(dev);
+					cache->object = in;
+					cache->chunk_id = chunk;
+					cache->dirty = 0;
+					cache->locked = 0;
+					yaffs_rd_data_obj(in, chunk,
+								      cache->data);
+				} else if (cache &&
+					!cache->dirty &&
+					!yaffs_check_alloc_available(dev, 1)) {
+					/* Drop the cache if it was a read cache item and
+					 * no space check has been made for it.
+					 */
+					 cache = NULL;
+				}
+
+				if (cache) {
+					yaffs_use_cache(dev, cache, 1);
+					cache->locked = 1;
+
+
+					memcpy(&cache->data[start], buffer,
+					       n_copy);
+
+
+					cache->locked = 0;
+					cache->n_bytes = n_writeback;
+
+					if (write_trhrough) {
+						chunk_written =
+						    yaffs_wr_data_obj
+						    (cache->object,
+						     cache->chunk_id,
+						     cache->data, cache->n_bytes,
+						     1);
+						cache->dirty = 0;
+					}
+
+				} else {
+					chunk_written = -1;	/* fail the write */
+				}
+			} else {
+				/* An incomplete start or end chunk (or maybe both start and end chunk)
+				 * Read into the local buffer then copy, then copy over and write back.
+				 */
+
+				__u8 *local_buffer =
+				    yaffs_get_temp_buffer(dev, __LINE__);
+
+				yaffs_rd_data_obj(in, chunk,
+							      local_buffer);
+
+
+
+				memcpy(&local_buffer[start], buffer, n_copy);
+
+				chunk_written =
+				    yaffs_wr_data_obj(in, chunk,
+								 local_buffer,
+								 n_writeback,
+								 0);
+
+				yaffs_release_temp_buffer(dev, local_buffer,
+							__LINE__);
+
+			}
+
+		} else {
+			/* A full chunk. Write directly from the supplied buffer. */
+
+
+
+			chunk_written =
+			    yaffs_wr_data_obj(in, chunk, buffer,
+							 dev->data_bytes_per_chunk,
+							 0);
+
+			/* Since we've overwritten the cached data, we better invalidate it. */
+			yaffs_invalidate_chunk_cache(in, chunk);
+		}
+
+		if (chunk_written >= 0) {
+			n -= n_copy;
+			offset += n_copy;
+			buffer += n_copy;
+			n_done += n_copy;
+		}
+
+	}
+
+	/* Update file object */
+
+	if ((start_write + n_done) > in->variant.file_variant.file_size)
+		in->variant.file_variant.file_size = (start_write + n_done);
+
+	in->dirty = 1;
+
+	return n_done;
+}
+
+int yaffs_wr_file(yaffs_obj_t *in, const __u8 *buffer, loff_t offset,
+			int n_bytes, int write_trhrough)
+{
+	yaffs2_handle_hole(in,offset);
+	return yaffs_do_file_wr(in,buffer,offset,n_bytes,write_trhrough);
+}
+
+
+
+/* ---------------------- File resizing stuff ------------------ */
+
+static void yaffs_prune_chunks(yaffs_obj_t *in, int new_size)
+{
+
+	yaffs_dev_t *dev = in->my_dev;
+	int old_size = in->variant.file_variant.file_size;
+
+	int last_del = 1 + (old_size - 1) / dev->data_bytes_per_chunk;
+
+	int start_del = 1 + (new_size + dev->data_bytes_per_chunk - 1) /
+	    dev->data_bytes_per_chunk;
+	int i;
+	int chunk_id;
+
+	/* Delete backwards so that we don't end up with holes if
+	 * power is lost part-way through the operation.
+	 */
+	for (i = last_del; i >= start_del; i--) {
+		/* NB this could be optimised somewhat,
+		 * eg. could retrieve the tags and write them without
+		 * using yaffs_chunk_del
+		 */
+
+		chunk_id = yaffs_find_del_file_chunk(in, i, NULL);
+		if (chunk_id > 0) {
+			if (chunk_id <
+			    (dev->internal_start_block * dev->param.chunks_per_block)
+			    || chunk_id >=
+			    ((dev->internal_end_block +
+			      1) * dev->param.chunks_per_block)) {
+				T(YAFFS_TRACE_ALWAYS,
+				  (TSTR("Found daft chunk_id %d for %d" TENDSTR),
+				   chunk_id, i));
+			} else {
+				in->n_data_chunks--;
+				yaffs_chunk_del(dev, chunk_id, 1, __LINE__);
+			}
+		}
+	}
+
+}
+
+
+void yaffs_resize_file_down( yaffs_obj_t *obj, loff_t new_size)
+{
+	int new_full;
+	__u32 new_partial;
+	yaffs_dev_t *dev = obj->my_dev;
+
+	yaffs_addr_to_chunk(dev, new_size, &new_full, &new_partial);
+
+	yaffs_prune_chunks(obj, new_size);
+
+	if (new_partial != 0) {
+		int last_chunk = 1 + new_full;
+		__u8 *local_buffer = yaffs_get_temp_buffer(dev, __LINE__);
+
+		/* Got to read and rewrite the last chunk with its new size and zero pad */
+		yaffs_rd_data_obj(obj, last_chunk, local_buffer);
+		memset(local_buffer + new_partial, 0,
+			dev->data_bytes_per_chunk - new_partial);
+
+		yaffs_wr_data_obj(obj, last_chunk, local_buffer,
+					     new_partial, 1);
+
+		yaffs_release_temp_buffer(dev, local_buffer, __LINE__);
+	}
+
+	obj->variant.file_variant.file_size = new_size;
+
+	yaffs_prune_tree(dev, &obj->variant.file_variant);
+}
+
+
+int yaffs_resize_file(yaffs_obj_t *in, loff_t new_size)
+{
+	yaffs_dev_t *dev = in->my_dev;
+	int old_size = in->variant.file_variant.file_size;
+
+	yaffs_flush_file_cache(in);
+	yaffs_invalidate_whole_cache(in);
+
+	yaffs_check_gc(dev,0);
+
+	if (in->variant_type != YAFFS_OBJECT_TYPE_FILE)
+		return YAFFS_FAIL;
+
+	if (new_size == old_size)
+		return YAFFS_OK;
+		
+	if(new_size > old_size){
+		yaffs2_handle_hole(in,new_size);
+		in->variant.file_variant.file_size = new_size;
+	} else {
+		/* new_size < old_size */ 
+		yaffs_resize_file_down(in, new_size);
+	} 
+
+	/* Write a new object header to reflect the resize.
+	 * show we've shrunk the file, if need be
+	 * Do this only if the file is not in the deleted directories
+	 * and is not shadowed.
+	 */
+	if (in->parent &&
+	    !in->is_shadowed &&
+	    in->parent->obj_id != YAFFS_OBJECTID_UNLINKED &&
+	    in->parent->obj_id != YAFFS_OBJECTID_DELETED)
+		yaffs_update_oh(in, NULL, 0, 0, 0, NULL);
+
+
+	return YAFFS_OK;
+}
+
+loff_t yaffs_get_file_size(yaffs_obj_t *obj)
+{
+	YCHAR *alias = NULL;
+	obj = yaffs_get_equivalent_obj(obj);
+
+	switch (obj->variant_type) {
+	case YAFFS_OBJECT_TYPE_FILE:
+		return obj->variant.file_variant.file_size;
+	case YAFFS_OBJECT_TYPE_SYMLINK:
+		alias = obj->variant.symlink_variant.alias;
+		if(!alias)
+			return 0;
+		return yaffs_strnlen(alias,YAFFS_MAX_ALIAS_LENGTH);
+	default:
+		return 0;
+	}
+}
+
+
+
+int yaffs_flush_file(yaffs_obj_t *in, int update_time, int data_sync)
+{
+	int ret_val;
+	if (in->dirty) {
+		yaffs_flush_file_cache(in);
+		if(data_sync) /* Only sync data */
+			ret_val=YAFFS_OK;
+		else {
+			if (update_time) {
+#ifdef CONFIG_YAFFS_WINCE
+				yfsd_win_file_time_now(in->win_mtime);
+#else
+
+				in->yst_mtime = Y_CURRENT_TIME;
+
+#endif
+			}
+
+			ret_val = (yaffs_update_oh(in, NULL, 0, 0, 0, NULL) >=
+				0) ? YAFFS_OK : YAFFS_FAIL;
+		}
+	} else {
+		ret_val = YAFFS_OK;
+	}
+
+	return ret_val;
+
+}
+
+static int yaffs_generic_obj_del(yaffs_obj_t *in)
+{
+
+	/* First off, invalidate the file's data in the cache, without flushing. */
+	yaffs_invalidate_whole_cache(in);
+
+	if (in->my_dev->param.is_yaffs2 && (in->parent != in->my_dev->del_dir)) {
+		/* Move to the unlinked directory so we have a record that it was deleted. */
+		yaffs_change_obj_name(in, in->my_dev->del_dir, _Y("deleted"), 0, 0);
+
+	}
+
+	yaffs_remove_obj_from_dir(in);
+	yaffs_chunk_del(in->my_dev, in->hdr_chunk, 1, __LINE__);
+	in->hdr_chunk = 0;
+
+	yaffs_free_obj(in);
+	return YAFFS_OK;
+
+}
+
+/* yaffs_del_file deletes the whole file data
+ * and the inode associated with the file.
+ * It does not delete the links associated with the file.
+ */
+static int yaffs_unlink_file_if_needed(yaffs_obj_t *in)
+{
+
+	int ret_val;
+	int del_now = 0;
+	yaffs_dev_t *dev = in->my_dev;
+
+	if (!in->my_inode)
+		del_now = 1;
+
+	if (del_now) {
+		ret_val =
+		    yaffs_change_obj_name(in, in->my_dev->del_dir,
+					   _Y("deleted"), 0, 0);
+		T(YAFFS_TRACE_TRACING,
+		  (TSTR("yaffs: immediate deletion of file %d" TENDSTR),
+		   in->obj_id));
+		in->deleted = 1;
+		in->my_dev->n_deleted_files++;
+		if (dev->param.disable_soft_del || dev->param.is_yaffs2)
+			yaffs_resize_file(in, 0);
+		yaffs_soft_del_file(in);
+	} else {
+		ret_val =
+		    yaffs_change_obj_name(in, in->my_dev->unlinked_dir,
+					   _Y("unlinked"), 0, 0);
+	}
+
+
+	return ret_val;
+}
+
+int yaffs_del_file(yaffs_obj_t *in)
+{
+	int ret_val = YAFFS_OK;
+	int deleted; /* Need to cache value on stack if in is freed */
+	yaffs_dev_t *dev = in->my_dev;
+
+	if (dev->param.disable_soft_del || dev->param.is_yaffs2)
+		yaffs_resize_file(in, 0);
+
+	if (in->n_data_chunks > 0) {
+		/* Use soft deletion if there is data in the file.
+		 * That won't be the case if it has been resized to zero.
+		 */
+		if (!in->unlinked)
+			ret_val = yaffs_unlink_file_if_needed(in);
+
+		deleted = in->deleted;
+
+		if (ret_val == YAFFS_OK && in->unlinked && !in->deleted) {
+			in->deleted = 1;
+			deleted = 1;
+			in->my_dev->n_deleted_files++;
+			yaffs_soft_del_file(in);
+		}
+		return deleted ? YAFFS_OK : YAFFS_FAIL;
+	} else {
+		/* The file has no data chunks so we toss it immediately */
+		yaffs_free_tnode(in->my_dev, in->variant.file_variant.top);
+		in->variant.file_variant.top = NULL;
+		yaffs_generic_obj_del(in);
+
+		return YAFFS_OK;
+	}
+}
+
+static int yaffs_is_non_empty_dir(yaffs_obj_t *obj)
+{
+	return (obj->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY) &&
+		!(ylist_empty(&obj->variant.dir_variant.children));
+}
+
+static int yaffs_del_dir(yaffs_obj_t *obj)
+{
+	/* First check that the directory is empty. */
+	if (yaffs_is_non_empty_dir(obj))
+		return YAFFS_FAIL;
+
+	return yaffs_generic_obj_del(obj);
+}
+
+static int yaffs_del_symlink(yaffs_obj_t *in)
+{
+	if(in->variant.symlink_variant.alias)
+		YFREE(in->variant.symlink_variant.alias);
+	in->variant.symlink_variant.alias=NULL;
+
+	return yaffs_generic_obj_del(in);
+}
+
+static int yaffs_del_link(yaffs_obj_t *in)
+{
+	/* remove this hardlink from the list assocaited with the equivalent
+	 * object
+	 */
+	ylist_del_init(&in->hard_links);
+	return yaffs_generic_obj_del(in);
+}
+
+int yaffs_del_obj(yaffs_obj_t *obj)
+{
+int ret_val = -1;
+	switch (obj->variant_type) {
+	case YAFFS_OBJECT_TYPE_FILE:
+		ret_val = yaffs_del_file(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_DIRECTORY:
+		if(!ylist_empty(&obj->variant.dir_variant.dirty)){
+			T(YAFFS_TRACE_BACKGROUND, (TSTR("Remove object %d from dirty directories" TENDSTR),obj->obj_id));
+			ylist_del_init(&obj->variant.dir_variant.dirty);
+		}
+		return yaffs_del_dir(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_SYMLINK:
+		ret_val = yaffs_del_symlink(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_HARDLINK:
+		ret_val = yaffs_del_link(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_SPECIAL:
+		ret_val = yaffs_generic_obj_del(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_UNKNOWN:
+		ret_val = 0;
+		break;		/* should not happen. */
+	}
+
+	return ret_val;
+}
+
+static int yaffs_unlink_worker(yaffs_obj_t *obj)
+{
+
+	int del_now = 0;
+
+	if (!obj->my_inode)
+		del_now = 1;
+
+	if(obj)
+		yaffs_update_parent(obj->parent);
+
+	if (obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) {
+		return yaffs_del_link(obj);
+	} else if (!ylist_empty(&obj->hard_links)) {
+		/* Curve ball: We're unlinking an object that has a hardlink.
+		 *
+		 * This problem arises because we are not strictly following
+		 * The Linux link/inode model.
+		 *
+		 * We can't really delete the object.
+		 * Instead, we do the following:
+		 * - Select a hardlink.
+		 * - Unhook it from the hard links
+		 * - Move it from its parent directory (so that the rename can work)
+		 * - Rename the object to the hardlink's name.
+		 * - Delete the hardlink
+		 */
+
+		yaffs_obj_t *hl;
+		yaffs_obj_t *parent;
+		int ret_val;
+		YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
+
+		hl = ylist_entry(obj->hard_links.next, yaffs_obj_t, hard_links);
+
+		yaffs_get_obj_name(hl, name, YAFFS_MAX_NAME_LENGTH + 1);
+		parent = hl->parent;
+
+		ylist_del_init(&hl->hard_links);
+
+ 		yaffs_add_obj_to_dir(obj->my_dev->unlinked_dir, hl);
+
+		ret_val = yaffs_change_obj_name(obj,parent, name, 0, 0);
+
+		if (ret_val == YAFFS_OK)
+			ret_val = yaffs_generic_obj_del(hl);
+
+		return ret_val;
+
+	} else if (del_now) {
+		switch (obj->variant_type) {
+		case YAFFS_OBJECT_TYPE_FILE:
+			return yaffs_del_file(obj);
+			break;
+		case YAFFS_OBJECT_TYPE_DIRECTORY:
+			ylist_del_init(&obj->variant.dir_variant.dirty);
+			return yaffs_del_dir(obj);
+			break;
+		case YAFFS_OBJECT_TYPE_SYMLINK:
+			return yaffs_del_symlink(obj);
+			break;
+		case YAFFS_OBJECT_TYPE_SPECIAL:
+			return yaffs_generic_obj_del(obj);
+			break;
+		case YAFFS_OBJECT_TYPE_HARDLINK:
+		case YAFFS_OBJECT_TYPE_UNKNOWN:
+		default:
+			return YAFFS_FAIL;
+		}
+	} else if(yaffs_is_non_empty_dir(obj))
+		return YAFFS_FAIL;
+	else
+		return yaffs_change_obj_name(obj, obj->my_dev->unlinked_dir,
+					   _Y("unlinked"), 0, 0);
+}
+
+
+static int yaffs_unlink_obj(yaffs_obj_t *obj)
+{
+
+	if (obj && obj->unlink_allowed)
+		return yaffs_unlink_worker(obj);
+
+	return YAFFS_FAIL;
+
+}
+int yaffs_unlinker(yaffs_obj_t *dir, const YCHAR *name)
+{
+	yaffs_obj_t *obj;
+
+	obj = yaffs_find_by_name(dir, name);
+	return yaffs_unlink_obj(obj);
+}
+
+/*----------------------- Initialisation Scanning ---------------------- */
+
+void yaffs_handle_shadowed_obj(yaffs_dev_t *dev, int obj_id,
+				int backward_scanning)
+{
+	yaffs_obj_t *obj;
+
+	if (!backward_scanning) {
+		/* Handle YAFFS1 forward scanning case
+		 * For YAFFS1 we always do the deletion
+		 */
+
+	} else {
+		/* Handle YAFFS2 case (backward scanning)
+		 * If the shadowed object exists then ignore.
+		 */
+		obj = yaffs_find_by_number(dev, obj_id);
+		if(obj)
+			return;
+	}
+
+	/* Let's create it (if it does not exist) assuming it is a file so that it can do shrinking etc.
+	 * We put it in unlinked dir to be cleaned up after the scanning
+	 */
+	obj =
+	    yaffs_find_or_create_by_number(dev, obj_id,
+					     YAFFS_OBJECT_TYPE_FILE);
+	if (!obj)
+		return;
+	obj->is_shadowed = 1;
+	yaffs_add_obj_to_dir(dev->unlinked_dir, obj);
+	obj->variant.file_variant.shrink_size = 0;
+	obj->valid = 1;		/* So that we don't read any other info for this file */
+
+}
+
+
+void yaffs_link_fixup(yaffs_dev_t *dev, yaffs_obj_t *hard_list)
+{
+	yaffs_obj_t *hl;
+	yaffs_obj_t *in;
+
+	while (hard_list) {
+		hl = hard_list;
+		hard_list = (yaffs_obj_t *) (hard_list->hard_links.next);
+
+		in = yaffs_find_by_number(dev,
+					      hl->variant.hardlink_variant.
+					      equiv_id);
+
+		if (in) {
+			/* Add the hardlink pointers */
+			hl->variant.hardlink_variant.equiv_obj = in;
+			ylist_add(&hl->hard_links, &in->hard_links);
+		} else {
+			/* Todo Need to report/handle this better.
+			 * Got a problem... hardlink to a non-existant object
+			 */
+			hl->variant.hardlink_variant.equiv_obj = NULL;
+			YINIT_LIST_HEAD(&hl->hard_links);
+
+		}
+	}
+}
+
+
+static void yaffs_strip_deleted_objs(yaffs_dev_t *dev)
+{
+	/*
+	*  Sort out state of unlinked and deleted objects after scanning.
+	*/
+	struct ylist_head *i;
+	struct ylist_head *n;
+	yaffs_obj_t *l;
+
+	if (dev->read_only)
+		return;
+
+	/* Soft delete all the unlinked files */
+	ylist_for_each_safe(i, n,
+		&dev->unlinked_dir->variant.dir_variant.children) {
+		if (i) {
+			l = ylist_entry(i, yaffs_obj_t, siblings);
+			yaffs_del_obj(l);
+		}
+	}
+
+	ylist_for_each_safe(i, n,
+		&dev->del_dir->variant.dir_variant.children) {
+		if (i) {
+			l = ylist_entry(i, yaffs_obj_t, siblings);
+			yaffs_del_obj(l);
+		}
+	}
+
+}
+
+/*
+ * This code iterates through all the objects making sure that they are rooted.
+ * Any unrooted objects are re-rooted in lost+found.
+ * An object needs to be in one of:
+ * - Directly under deleted, unlinked
+ * - Directly or indirectly under root.
+ *
+ * Note:
+ *  This code assumes that we don't ever change the current relationships between
+ *  directories:
+ *   root_dir->parent == unlinked_dir->parent == del_dir->parent == NULL
+ *   lost-n-found->parent == root_dir
+ *
+ * This fixes the problem where directories might have inadvertently been deleted
+ * leaving the object "hanging" without being rooted in the directory tree.
+ */
+ 
+static int yaffs_has_null_parent(yaffs_dev_t *dev, yaffs_obj_t *obj)
+{
+	return (obj == dev->del_dir ||
+		obj == dev->unlinked_dir||
+		obj == dev->root_dir);
+}
+
+static void yaffs_fix_hanging_objs(yaffs_dev_t *dev)
+{
+	yaffs_obj_t *obj;
+	yaffs_obj_t *parent;
+	int i;
+	struct ylist_head *lh;
+	struct ylist_head *n;
+	int depth_limit;
+	int hanging;
+
+	if (dev->read_only)
+		return;
+
+	/* Iterate through the objects in each hash entry,
+	 * looking at each object.
+	 * Make sure it is rooted.
+	 */
+
+	for (i = 0; i <  YAFFS_NOBJECT_BUCKETS; i++) {
+		ylist_for_each_safe(lh, n, &dev->obj_bucket[i].list) {
+			if (lh) {
+				obj = ylist_entry(lh, yaffs_obj_t, hash_link);
+				parent= obj->parent;
+				
+				if(yaffs_has_null_parent(dev,obj)){
+					/* These directories are not hanging */
+					hanging = 0;
+				}
+				else if(!parent || parent->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
+					hanging = 1;
+				else if(yaffs_has_null_parent(dev,parent))
+					hanging = 0;
+				else {
+					/*
+					 * Need to follow the parent chain to see if it is hanging.
+					 */
+					hanging = 0;
+					depth_limit=100;
+
+					while(parent != dev->root_dir &&
+						parent->parent &&
+						parent->parent->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY &&
+						depth_limit > 0){
+						parent = parent->parent;
+						depth_limit--;
+					}
+					if(parent != dev->root_dir)
+						hanging = 1;
+				}
+				if(hanging){
+					T(YAFFS_TRACE_SCAN,
+					  (TSTR("Hanging object %d moved to lost and found" TENDSTR),
+					  	obj->obj_id));
+					yaffs_add_obj_to_dir(dev->lost_n_found,obj);
+				}
+			}
+		}
+	}
+}
+
+
+/*
+ * Delete directory contents for cleaning up lost and found.
+ */
+static void yaffs_del_dir_contents(yaffs_obj_t *dir)
+{
+	yaffs_obj_t *obj;
+	struct ylist_head *lh;
+	struct ylist_head *n;
+
+	if(dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
+		YBUG();
+	
+	ylist_for_each_safe(lh, n, &dir->variant.dir_variant.children) {
+		if (lh) {
+			obj = ylist_entry(lh, yaffs_obj_t, siblings);
+			if(obj->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY)
+				yaffs_del_dir_contents(obj);
+
+			T(YAFFS_TRACE_SCAN,
+				(TSTR("Deleting lost_found object %d" TENDSTR),
+				obj->obj_id));
+
+			/* Need to use UnlinkObject since Delete would not handle
+			 * hardlinked objects correctly.
+			 */
+			yaffs_unlink_obj(obj); 
+		}
+	}
+			
+}
+
+static void yaffs_empty_l_n_f(yaffs_dev_t *dev)
+{
+	yaffs_del_dir_contents(dev->lost_n_found);
+}
+
+static void yaffs_check_obj_details_loaded(yaffs_obj_t *in)
+{
+	__u8 *chunk_data;
+	yaffs_obj_header *oh;
+	yaffs_dev_t *dev;
+	yaffs_ext_tags tags;
+	int result;
+	int alloc_failed = 0;
+
+	if (!in)
+		return;
+
+	dev = in->my_dev;
+
+#if 0
+	T(YAFFS_TRACE_SCAN, (TSTR("details for object %d %s loaded" TENDSTR),
+		in->obj_id,
+		in->lazy_loaded ? "not yet" : "already"));
+#endif
+
+	if (in->lazy_loaded && in->hdr_chunk > 0) {
+		in->lazy_loaded = 0;
+		chunk_data = yaffs_get_temp_buffer(dev, __LINE__);
+
+		result = yaffs_rd_chunk_tags_nand(dev, in->hdr_chunk, chunk_data, &tags);
+		oh = (yaffs_obj_header *) chunk_data;
+
+		in->yst_mode = oh->yst_mode;
+#ifdef CONFIG_YAFFS_WINCE
+		in->win_atime[0] = oh->win_atime[0];
+		in->win_ctime[0] = oh->win_ctime[0];
+		in->win_mtime[0] = oh->win_mtime[0];
+		in->win_atime[1] = oh->win_atime[1];
+		in->win_ctime[1] = oh->win_ctime[1];
+		in->win_mtime[1] = oh->win_mtime[1];
+#else
+		in->yst_uid = oh->yst_uid;
+		in->yst_gid = oh->yst_gid;
+		in->yst_atime = oh->yst_atime;
+		in->yst_mtime = oh->yst_mtime;
+		in->yst_ctime = oh->yst_ctime;
+		in->yst_rdev = oh->yst_rdev;
+
+#endif
+		yaffs_set_obj_name_from_oh(in, oh);
+
+		if (in->variant_type == YAFFS_OBJECT_TYPE_SYMLINK) {
+			in->variant.symlink_variant.alias =
+						    yaffs_clone_str(oh->alias);
+			if (!in->variant.symlink_variant.alias)
+				alloc_failed = 1; /* Not returned to caller */
+		}
+
+		yaffs_release_temp_buffer(dev, chunk_data, __LINE__);
+	}
+}
+
+/*------------------------------  Directory Functions ----------------------------- */
+
+/*
+ *yaffs_update_parent() handles fixing a directories mtime and ctime when a new
+ * link (ie. name) is created or deleted in the directory.
+ *
+ * ie.
+ *   create dir/a : update dir's mtime/ctime
+ *   rm dir/a:   update dir's mtime/ctime
+ *   modify dir/a: don't update dir's mtimme/ctime
+ *
+ * This can be handled immediately or defered. Defering helps reduce the number
+ * of updates when many files in a directory are changed within a brief period.
+ *
+ * If the directory updating is defered then yaffs_update_dirty_dirs must be
+ * called periodically.
+ */
+ 
+static void yaffs_update_parent(yaffs_obj_t *obj)
+{
+	yaffs_dev_t *dev;
+	if(!obj)
+		return;
+#ifndef CONFIG_YAFFS_WINCE
+
+	dev = obj->my_dev;
+	obj->dirty = 1;
+	obj->yst_mtime = obj->yst_ctime = Y_CURRENT_TIME;
+	if(dev->param.defered_dir_update){
+		struct ylist_head *link = &obj->variant.dir_variant.dirty; 
+	
+		if(ylist_empty(link)){
+			ylist_add(link,&dev->dirty_dirs);
+			T(YAFFS_TRACE_BACKGROUND, (TSTR("Added object %d to dirty directories" TENDSTR),obj->obj_id));
+		}
+
+	} else
+		yaffs_update_oh(obj, NULL, 0, 0, 0, NULL);
+#endif
+}
+
+void yaffs_update_dirty_dirs(yaffs_dev_t *dev)
+{
+	struct ylist_head *link;
+	yaffs_obj_t *obj;
+	yaffs_dir_s *d_s;
+	yaffs_obj_variant *o_v;
+
+	T(YAFFS_TRACE_BACKGROUND, (TSTR("Update dirty directories" TENDSTR)));
+
+	while(!ylist_empty(&dev->dirty_dirs)){
+		link = dev->dirty_dirs.next;
+		ylist_del_init(link);
+		
+		d_s=ylist_entry(link,yaffs_dir_s,dirty);
+		o_v = ylist_entry(d_s,yaffs_obj_variant,dir_variant);
+		obj = ylist_entry(o_v,yaffs_obj_t,variant);
+
+		T(YAFFS_TRACE_BACKGROUND, (TSTR("Update directory %d" TENDSTR), obj->obj_id));
+
+		if(obj->dirty)
+			yaffs_update_oh(obj, NULL, 0, 0, 0, NULL);
+	}
+}
+
+static void yaffs_remove_obj_from_dir(yaffs_obj_t *obj)
+{
+	yaffs_dev_t *dev = obj->my_dev;
+	yaffs_obj_t *parent;
+
+	yaffs_verify_obj_in_dir(obj);
+	parent = obj->parent;
+
+	yaffs_verify_dir(parent);
+
+	if (dev && dev->param.remove_obj_fn)
+		dev->param.remove_obj_fn(obj);
+
+
+	ylist_del_init(&obj->siblings);
+	obj->parent = NULL;
+	
+	yaffs_verify_dir(parent);
+}
+
+void yaffs_add_obj_to_dir(yaffs_obj_t *directory,
+					yaffs_obj_t *obj)
+{
+	if (!directory) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("tragedy: Trying to add an object to a null pointer directory"
+		    TENDSTR)));
+		YBUG();
+		return;
+	}
+	if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("tragedy: Trying to add an object to a non-directory"
+		    TENDSTR)));
+		YBUG();
+	}
+
+	if (obj->siblings.prev == NULL) {
+		/* Not initialised */
+		YBUG();
+	}
+
+
+	yaffs_verify_dir(directory);
+
+	yaffs_remove_obj_from_dir(obj);
+
+
+	/* Now add it */
+	ylist_add(&obj->siblings, &directory->variant.dir_variant.children);
+	obj->parent = directory;
+
+	if (directory == obj->my_dev->unlinked_dir
+			|| directory == obj->my_dev->del_dir) {
+		obj->unlinked = 1;
+		obj->my_dev->n_unlinked_files++;
+		obj->rename_allowed = 0;
+	}
+
+	yaffs_verify_dir(directory);
+	yaffs_verify_obj_in_dir(obj);
+}
+
+yaffs_obj_t *yaffs_find_by_name(yaffs_obj_t *directory,
+				     const YCHAR *name)
+{
+	int sum;
+
+	struct ylist_head *i;
+	YCHAR buffer[YAFFS_MAX_NAME_LENGTH + 1];
+
+	yaffs_obj_t *l;
+
+	if (!name)
+		return NULL;
+
+	if (!directory) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("tragedy: yaffs_find_by_name: null pointer directory"
+		    TENDSTR)));
+		YBUG();
+		return NULL;
+	}
+	if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("tragedy: yaffs_find_by_name: non-directory" TENDSTR)));
+		YBUG();
+	}
+
+	sum = yaffs_calc_name_sum(name);
+
+	ylist_for_each(i, &directory->variant.dir_variant.children) {
+		if (i) {
+			l = ylist_entry(i, yaffs_obj_t, siblings);
+
+			if (l->parent != directory)
+				YBUG();
+
+			yaffs_check_obj_details_loaded(l);
+
+			/* Special case for lost-n-found */
+			if (l->obj_id == YAFFS_OBJECTID_LOSTNFOUND) {
+				if (yaffs_strcmp(name, YAFFS_LOSTNFOUND_NAME) == 0)
+					return l;
+			} else if (yaffs_sum_cmp(l->sum, sum) || l->hdr_chunk <= 0) {
+				/* LostnFound chunk called Objxxx
+				 * Do a real check
+				 */
+				yaffs_get_obj_name(l, buffer,
+						    YAFFS_MAX_NAME_LENGTH + 1);
+				if (yaffs_strncmp(name, buffer, YAFFS_MAX_NAME_LENGTH) == 0)
+					return l;
+			}
+		}
+	}
+
+	return NULL;
+}
+
+
+#if 0
+int yaffs_ApplyToDirectoryChildren(yaffs_obj_t *the_dir,
+					int (*fn) (yaffs_obj_t *))
+{
+	struct ylist_head *i;
+	yaffs_obj_t *l;
+
+	if (!the_dir) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("tragedy: yaffs_find_by_name: null pointer directory"
+		    TENDSTR)));
+		YBUG();
+		return YAFFS_FAIL;
+	}
+	if (the_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("tragedy: yaffs_find_by_name: non-directory" TENDSTR)));
+		YBUG();
+		return YAFFS_FAIL;
+	}
+
+	ylist_for_each(i, &the_dir->variant.dir_variant.children) {
+		if (i) {
+			l = ylist_entry(i, yaffs_obj_t, siblings);
+			if (l && !fn(l))
+				return YAFFS_FAIL;
+		}
+	}
+
+	return YAFFS_OK;
+
+}
+#endif
+
+/* GetEquivalentObject dereferences any hard links to get to the
+ * actual object.
+ */
+
+yaffs_obj_t *yaffs_get_equivalent_obj(yaffs_obj_t *obj)
+{
+	if (obj && obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) {
+		/* We want the object id of the equivalent object, not this one */
+		obj = obj->variant.hardlink_variant.equiv_obj;
+		yaffs_check_obj_details_loaded(obj);
+	}
+	return obj;
+}
+
+/*
+ *  A note or two on object names.
+ *  * If the object name is missing, we then make one up in the form objnnn
+ *
+ *  * ASCII names are stored in the object header's name field from byte zero
+ *  * Unicode names are historically stored starting from byte zero.
+ *
+ * Then there are automatic Unicode names...
+ * The purpose of these is to save names in a way that can be read as
+ * ASCII or Unicode names as appropriate, thus allowing a Unicode and ASCII
+ * system to share files.
+ *
+ * These automatic unicode are stored slightly differently...
+ *  - If the name can fit in the ASCII character space then they are saved as 
+ *    ascii names as per above.
+ *  - If the name needs Unicode then the name is saved in Unicode
+ *    starting at oh->name[1].
+
+ */
+static void yaffs_fix_null_name(yaffs_obj_t * obj,YCHAR * name, int buffer_size)
+{
+	/* Create an object name if we could not find one. */
+	if(yaffs_strnlen(name,YAFFS_MAX_NAME_LENGTH) == 0){
+		YCHAR local_name[20];
+		YCHAR num_string[20];
+		YCHAR *x = &num_string[19];
+		unsigned v = obj->obj_id;
+		num_string[19] = 0;
+		while(v>0){
+			x--;
+			*x = '0' + (v % 10);
+			v /= 10;
+		}
+		/* make up a name */
+		yaffs_strcpy(local_name, YAFFS_LOSTNFOUND_PREFIX);
+		yaffs_strcat(local_name,x);
+		yaffs_strncpy(name, local_name, buffer_size - 1);
+	}
+}
+
+static void yaffs_load_name_from_oh(yaffs_dev_t *dev,YCHAR *name, const YCHAR *oh_name, int buff_size)
+{
+#ifdef CONFIG_YAFFS_AUTO_UNICODE
+	if(dev->param.auto_unicode){
+		if(*oh_name){
+			/* It is an ASCII name, so do an ASCII to unicode conversion */
+			const char *ascii_oh_name = (const char *)oh_name;
+			int n = buff_size - 1;
+			while(n > 0 && *ascii_oh_name){
+				*name = *ascii_oh_name;
+				name++;
+				ascii_oh_name++;
+				n--;
+			}
+		} else 
+			yaffs_strncpy(name,oh_name+1, buff_size -1);
+	} else
+#endif
+		yaffs_strncpy(name, oh_name, buff_size - 1);
+}
+
+
+static void yaffs_load_oh_from_name(yaffs_dev_t *dev, YCHAR *oh_name, const YCHAR *name)
+{
+#ifdef CONFIG_YAFFS_AUTO_UNICODE
+
+	int is_ascii;
+	YCHAR *w;
+
+	if(dev->param.auto_unicode){
+
+		is_ascii = 1;
+		w = name;
+	
+		/* Figure out if the name will fit in ascii character set */
+		while(is_ascii && *w){
+			if((*w) & 0xff00)
+				is_ascii = 0;
+			w++;
+		}
+
+		if(is_ascii){
+			/* It is an ASCII name, so do a unicode to ascii conversion */
+			char *ascii_oh_name = (char *)oh_name;
+			int n = YAFFS_MAX_NAME_LENGTH  - 1;
+			while(n > 0 && *name){
+				*ascii_oh_name= *name;
+				name++;
+				ascii_oh_name++;
+				n--;
+			}
+		} else{
+			/* It is a unicode name, so save starting at the second YCHAR */
+			*oh_name = 0;
+			yaffs_strncpy(oh_name+1,name, YAFFS_MAX_NAME_LENGTH -2);
+		}
+	}
+	else 
+#endif
+		yaffs_strncpy(oh_name,name, YAFFS_MAX_NAME_LENGTH - 1);
+
+}
+
+int yaffs_get_obj_name(yaffs_obj_t * obj, YCHAR * name, int buffer_size)
+{
+	memset(name, 0, buffer_size * sizeof(YCHAR));
+	
+	yaffs_check_obj_details_loaded(obj);
+
+	if (obj->obj_id == YAFFS_OBJECTID_LOSTNFOUND) {
+		yaffs_strncpy(name, YAFFS_LOSTNFOUND_NAME, buffer_size - 1);
+	} 
+#ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
+	else if (obj->short_name[0]) {
+		yaffs_strcpy(name, obj->short_name);
+	}
+#endif
+	else if(obj->hdr_chunk > 0) {
+		int result;
+		__u8 *buffer = yaffs_get_temp_buffer(obj->my_dev, __LINE__);
+
+		yaffs_obj_header *oh = (yaffs_obj_header *) buffer;
+
+		memset(buffer, 0, obj->my_dev->data_bytes_per_chunk);
+
+		if (obj->hdr_chunk > 0) {
+			result = yaffs_rd_chunk_tags_nand(obj->my_dev,
+							obj->hdr_chunk, buffer,
+							NULL);
+		}
+		yaffs_load_name_from_oh(obj->my_dev,name,oh->name,buffer_size);
+
+		yaffs_release_temp_buffer(obj->my_dev, buffer, __LINE__);
+	}
+
+	yaffs_fix_null_name(obj,name,buffer_size);
+
+	return yaffs_strnlen(name,YAFFS_MAX_NAME_LENGTH);
+}
+
+
+int yaffs_get_obj_length(yaffs_obj_t *obj)
+{
+	/* Dereference any hard linking */
+	obj = yaffs_get_equivalent_obj(obj);
+
+	if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE)
+		return obj->variant.file_variant.file_size;
+	if (obj->variant_type == YAFFS_OBJECT_TYPE_SYMLINK){
+		if(!obj->variant.symlink_variant.alias)
+			return 0;
+		return yaffs_strnlen(obj->variant.symlink_variant.alias,YAFFS_MAX_ALIAS_LENGTH);
+	} else {
+		/* Only a directory should drop through to here */
+		return obj->my_dev->data_bytes_per_chunk;
+	}
+}
+
+int yaffs_get_obj_link_count(yaffs_obj_t *obj)
+{
+	int count = 0;
+	struct ylist_head *i;
+
+	if (!obj->unlinked)
+		count++;		/* the object itself */
+
+	ylist_for_each(i, &obj->hard_links)
+		count++;		/* add the hard links; */
+
+	return count;
+}
+
+int yaffs_get_obj_inode(yaffs_obj_t *obj)
+{
+	obj = yaffs_get_equivalent_obj(obj);
+
+	return obj->obj_id;
+}
+
+unsigned yaffs_get_obj_type(yaffs_obj_t *obj)
+{
+	obj = yaffs_get_equivalent_obj(obj);
+
+	switch (obj->variant_type) {
+	case YAFFS_OBJECT_TYPE_FILE:
+		return DT_REG;
+		break;
+	case YAFFS_OBJECT_TYPE_DIRECTORY:
+		return DT_DIR;
+		break;
+	case YAFFS_OBJECT_TYPE_SYMLINK:
+		return DT_LNK;
+		break;
+	case YAFFS_OBJECT_TYPE_HARDLINK:
+		return DT_REG;
+		break;
+	case YAFFS_OBJECT_TYPE_SPECIAL:
+		if (S_ISFIFO(obj->yst_mode))
+			return DT_FIFO;
+		if (S_ISCHR(obj->yst_mode))
+			return DT_CHR;
+		if (S_ISBLK(obj->yst_mode))
+			return DT_BLK;
+		if (S_ISSOCK(obj->yst_mode))
+			return DT_SOCK;
+	default:
+		return DT_REG;
+		break;
+	}
+}
+
+YCHAR *yaffs_get_symlink_alias(yaffs_obj_t *obj)
+{
+	obj = yaffs_get_equivalent_obj(obj);
+	if (obj->variant_type == YAFFS_OBJECT_TYPE_SYMLINK)
+		return yaffs_clone_str(obj->variant.symlink_variant.alias);
+	else
+		return yaffs_clone_str(_Y(""));
+}
+
+#ifndef CONFIG_YAFFS_WINCE
+
+int yaffs_set_attribs(yaffs_obj_t *obj, struct iattr *attr)
+{
+	unsigned int valid = attr->ia_valid;
+
+	if (valid & ATTR_MODE)
+		obj->yst_mode = attr->ia_mode;
+	if (valid & ATTR_UID)
+		obj->yst_uid = attr->ia_uid;
+	if (valid & ATTR_GID)
+		obj->yst_gid = attr->ia_gid;
+
+	if (valid & ATTR_ATIME)
+		obj->yst_atime = Y_TIME_CONVERT(attr->ia_atime);
+	if (valid & ATTR_CTIME)
+		obj->yst_ctime = Y_TIME_CONVERT(attr->ia_ctime);
+	if (valid & ATTR_MTIME)
+		obj->yst_mtime = Y_TIME_CONVERT(attr->ia_mtime);
+
+	if (valid & ATTR_SIZE)
+		yaffs_resize_file(obj, attr->ia_size);
+
+	yaffs_update_oh(obj, NULL, 1, 0, 0, NULL);
+
+	return YAFFS_OK;
+
+}
+int yaffs_get_attribs(yaffs_obj_t *obj, struct iattr *attr)
+{
+	unsigned int valid = 0;
+
+	attr->ia_mode = obj->yst_mode;
+	valid |= ATTR_MODE;
+	attr->ia_uid = obj->yst_uid;
+	valid |= ATTR_UID;
+	attr->ia_gid = obj->yst_gid;
+	valid |= ATTR_GID;
+
+	Y_TIME_CONVERT(attr->ia_atime) = obj->yst_atime;
+	valid |= ATTR_ATIME;
+	Y_TIME_CONVERT(attr->ia_ctime) = obj->yst_ctime;
+	valid |= ATTR_CTIME;
+	Y_TIME_CONVERT(attr->ia_mtime) = obj->yst_mtime;
+	valid |= ATTR_MTIME;
+
+	attr->ia_size = yaffs_get_file_size(obj);
+	valid |= ATTR_SIZE;
+
+	attr->ia_valid = valid;
+
+	return YAFFS_OK;
+}
+
+#endif
+
+
+static int yaffs_do_xattrib_mod(yaffs_obj_t *obj, int set, const YCHAR *name, const void *value, int size, int flags)
+{
+	yaffs_xattr_mod xmod;
+
+	int result;
+
+	xmod.set = set;
+	xmod.name = name;
+	xmod.data = value;
+	xmod.size =  size;
+	xmod.flags = flags;
+	xmod.result = -ENOSPC;
+
+	result = yaffs_update_oh(obj, NULL, 0, 0, 0, &xmod);
+
+	if(result > 0)
+		return xmod.result;
+	else
+		return -ENOSPC;
+}
+
+static int yaffs_apply_xattrib_mod(yaffs_obj_t *obj, char *buffer, yaffs_xattr_mod *xmod)
+{
+	int retval = 0;
+	int x_offs = sizeof(yaffs_obj_header);
+	yaffs_dev_t *dev = obj->my_dev;
+	int x_size = dev->data_bytes_per_chunk - sizeof(yaffs_obj_header);
+
+	char * x_buffer = buffer + x_offs;
+
+	if(xmod->set)
+		retval = nval_set(x_buffer, x_size, xmod->name, xmod->data, xmod->size, xmod->flags);
+	else
+		retval = nval_del(x_buffer, x_size, xmod->name);
+
+	obj->has_xattr = nval_hasvalues(x_buffer, x_size);
+	obj->xattr_known = 1;
+
+	xmod->result = retval;
+
+	return retval;
+}
+
+static int yaffs_do_xattrib_fetch(yaffs_obj_t *obj, const YCHAR *name, void *value, int size)
+{
+	char *buffer = NULL;
+	int result;
+	yaffs_ext_tags tags;
+	yaffs_dev_t *dev = obj->my_dev;
+	int x_offs = sizeof(yaffs_obj_header);
+	int x_size = dev->data_bytes_per_chunk - sizeof(yaffs_obj_header);
+
+	char * x_buffer;
+
+	int retval = 0;
+
+	if(obj->hdr_chunk < 1)
+		return -ENODATA;
+
+	/* If we know that the object has no xattribs then don't do all the
+	 * reading and parsing.
+	 */
+	if(obj->xattr_known && !obj->has_xattr){
+		if(name)
+			return -ENODATA;
+		else
+			return 0;
+	}
+
+	buffer = (char *) yaffs_get_temp_buffer(dev, __LINE__);
+	if(!buffer)
+		return -ENOMEM;
+
+	result = yaffs_rd_chunk_tags_nand(dev,obj->hdr_chunk, (__u8 *)buffer, &tags);
+
+	if(result != YAFFS_OK)
+		retval = -ENOENT;
+	else{
+		x_buffer =  buffer + x_offs;
+
+		if (!obj->xattr_known){
+			obj->has_xattr = nval_hasvalues(x_buffer, x_size);
+			obj->xattr_known = 1;
+		}
+
+		if(name)
+			retval = nval_get(x_buffer, x_size, name, value, size);
+		else
+			retval = nval_list(x_buffer, x_size, value,size);
+	}
+	yaffs_release_temp_buffer(dev,(__u8 *)buffer,__LINE__);
+	return retval;
+}
+
+int yaffs_set_xattrib(yaffs_obj_t *obj, const YCHAR *name, const void * value, int size, int flags)
+{
+	return yaffs_do_xattrib_mod(obj, 1, name, value, size, flags);
+}
+
+int yaffs_remove_xattrib(yaffs_obj_t *obj, const YCHAR *name)
+{
+	return yaffs_do_xattrib_mod(obj, 0, name, NULL, 0, 0);
+}
+
+int yaffs_get_xattrib(yaffs_obj_t *obj, const YCHAR *name, void *value, int size)
+{
+	return yaffs_do_xattrib_fetch(obj, name, value, size);
+}
+
+int yaffs_list_xattrib(yaffs_obj_t *obj, char *buffer, int size)
+{
+	return yaffs_do_xattrib_fetch(obj, NULL, buffer,size);
+}
+
+
+
+#if 0
+int yaffs_dump_obj(yaffs_obj_t *obj)
+{
+	YCHAR name[257];
+
+	yaffs_get_obj_name(obj, name, YAFFS_MAX_NAME_LENGTH + 1);
+
+	T(YAFFS_TRACE_ALWAYS,
+	  (TSTR
+	   ("Object %d, inode %d \"%s\"\n dirty %d valid %d serial %d sum %d"
+	    " chunk %d type %d size %d\n"
+	    TENDSTR), obj->obj_id, yaffs_get_obj_inode(obj), name,
+	   obj->dirty, obj->valid, obj->serial, obj->sum, obj->hdr_chunk,
+	   yaffs_get_obj_type(obj), yaffs_get_obj_length(obj)));
+
+	return YAFFS_OK;
+}
+#endif
+
+/*---------------------------- Initialisation code -------------------------------------- */
+
+static int yaffs_cehck_dev_fns(const yaffs_dev_t *dev)
+{
+
+	/* Common functions, gotta have */
+	if (!dev->param.erase_fn || !dev->param.initialise_flash_fn)
+		return 0;
+
+#ifdef CONFIG_YAFFS_YAFFS2
+
+	/* Can use the "with tags" style interface for yaffs1 or yaffs2 */
+	if (dev->param.write_chunk_tags_fn &&
+	    dev->param.read_chunk_tags_fn &&
+	    !dev->param.write_chunk_fn &&
+	    !dev->param.read_chunk_fn &&
+	    dev->param.bad_block_fn &&
+	    dev->param.query_block_fn)
+		return 1;
+#endif
+
+	/* Can use the "spare" style interface for yaffs1 */
+	if (!dev->param.is_yaffs2 &&
+	    !dev->param.write_chunk_tags_fn &&
+	    !dev->param.read_chunk_tags_fn &&
+	    dev->param.write_chunk_fn &&
+	    dev->param.read_chunk_fn &&
+	    !dev->param.bad_block_fn &&
+	    !dev->param.query_block_fn)
+		return 1;
+
+	return 0;	/* bad */
+}
+
+
+static int yaffs_create_initial_dir(yaffs_dev_t *dev)
+{
+	/* Initialise the unlinked, deleted, root and lost and found directories */
+
+	dev->lost_n_found = dev->root_dir =  NULL;
+	dev->unlinked_dir = dev->del_dir = NULL;
+
+	dev->unlinked_dir =
+	    yaffs_create_fake_dir(dev, YAFFS_OBJECTID_UNLINKED, S_IFDIR);
+
+	dev->del_dir =
+	    yaffs_create_fake_dir(dev, YAFFS_OBJECTID_DELETED, S_IFDIR);
+
+	dev->root_dir =
+	    yaffs_create_fake_dir(dev, YAFFS_OBJECTID_ROOT,
+				      YAFFS_ROOT_MODE | S_IFDIR);
+	dev->lost_n_found =
+	    yaffs_create_fake_dir(dev, YAFFS_OBJECTID_LOSTNFOUND,
+				      YAFFS_LOSTNFOUND_MODE | S_IFDIR);
+
+	if (dev->lost_n_found && dev->root_dir && dev->unlinked_dir && dev->del_dir) {
+		yaffs_add_obj_to_dir(dev->root_dir, dev->lost_n_found);
+		return YAFFS_OK;
+	}
+
+	return YAFFS_FAIL;
+}
+
+int yaffs_guts_initialise(yaffs_dev_t *dev)
+{
+	int init_failed = 0;
+	unsigned x;
+	int bits;
+
+	T(YAFFS_TRACE_TRACING, (TSTR("yaffs: yaffs_guts_initialise()" TENDSTR)));
+
+	/* Check stuff that must be set */
+
+	if (!dev) {
+		T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Need a device" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	dev->internal_start_block = dev->param.start_block;
+	dev->internal_end_block = dev->param.end_block;
+	dev->block_offset = 0;
+	dev->chunk_offset = 0;
+	dev->n_free_chunks = 0;
+
+	dev->gc_block = 0;
+
+	if (dev->param.start_block == 0) {
+		dev->internal_start_block = dev->param.start_block + 1;
+		dev->internal_end_block = dev->param.end_block + 1;
+		dev->block_offset = 1;
+		dev->chunk_offset = dev->param.chunks_per_block;
+	}
+
+	/* Check geometry parameters. */
+
+	if ((!dev->param.inband_tags && dev->param.is_yaffs2 && dev->param.total_bytes_per_chunk < 1024) ||
+	    (!dev->param.is_yaffs2 && dev->param.total_bytes_per_chunk < 512) ||
+	    (dev->param.inband_tags && !dev->param.is_yaffs2) ||
+	     dev->param.chunks_per_block < 2 ||
+	     dev->param.n_reserved_blocks < 2 ||
+	     dev->internal_start_block <= 0 ||
+	     dev->internal_end_block <= 0 ||
+	     dev->internal_end_block <= (dev->internal_start_block + dev->param.n_reserved_blocks + 2)) {	/* otherwise it is too small */
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("yaffs: NAND geometry problems: chunk size %d, type is yaffs%s, inband_tags %d "
+		    TENDSTR), dev->param.total_bytes_per_chunk, dev->param.is_yaffs2 ? "2" : "", dev->param.inband_tags));
+		return YAFFS_FAIL;
+	}
+
+	if (yaffs_init_nand(dev) != YAFFS_OK) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR("yaffs: InitialiseNAND failed" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	/* Sort out space for inband tags, if required */
+	if (dev->param.inband_tags)
+		dev->data_bytes_per_chunk = dev->param.total_bytes_per_chunk - sizeof(yaffs_packed_tags2_tags_only);
+	else
+		dev->data_bytes_per_chunk = dev->param.total_bytes_per_chunk;
+
+	/* Got the right mix of functions? */
+	if (!yaffs_cehck_dev_fns(dev)) {
+		/* Function missing */
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("yaffs: device function(s) missing or wrong\n" TENDSTR)));
+
+		return YAFFS_FAIL;
+	}
+
+	/* This is really a compilation check. */
+	if (!yaffs_check_structures()) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR("yaffs_check_structures failed\n" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	if (dev->is_mounted) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR("yaffs: device already mounted\n" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	/* Finished with most checks. One or two more checks happen later on too. */
+
+	dev->is_mounted = 1;
+
+	/* OK now calculate a few things for the device */
+
+	/*
+	 *  Calculate all the chunk size manipulation numbers:
+	 */
+	x = dev->data_bytes_per_chunk;
+	/* We always use dev->chunk_shift and dev->chunk_div */
+	dev->chunk_shift = calc_shifts(x);
+	x >>= dev->chunk_shift;
+	dev->chunk_div = x;
+	/* We only use chunk mask if chunk_div is 1 */
+	dev->chunk_mask = (1<<dev->chunk_shift) - 1;
+
+	/*
+	 * Calculate chunk_grp_bits.
+	 * We need to find the next power of 2 > than internal_end_block
+	 */
+
+	x = dev->param.chunks_per_block * (dev->internal_end_block + 1);
+
+	bits = calc_shifts_ceiling(x);
+
+	/* Set up tnode width if wide tnodes are enabled. */
+	if (!dev->param.wide_tnodes_disabled) {
+		/* bits must be even so that we end up with 32-bit words */
+		if (bits & 1)
+			bits++;
+		if (bits < 16)
+			dev->tnode_width = 16;
+		else
+			dev->tnode_width = bits;
+	} else
+		dev->tnode_width = 16;
+
+	dev->tnode_mask = (1<<dev->tnode_width)-1;
+
+	/* Level0 Tnodes are 16 bits or wider (if wide tnodes are enabled),
+	 * so if the bitwidth of the
+	 * chunk range we're using is greater than 16 we need
+	 * to figure out chunk shift and chunk_grp_size
+	 */
+
+	if (bits <= dev->tnode_width)
+		dev->chunk_grp_bits = 0;
+	else
+		dev->chunk_grp_bits = bits - dev->tnode_width;
+
+	dev->tnode_size = (dev->tnode_width * YAFFS_NTNODES_LEVEL0)/8;
+	if(dev->tnode_size < sizeof(yaffs_tnode_t))
+		dev->tnode_size = sizeof(yaffs_tnode_t);
+
+	dev->chunk_grp_size = 1 << dev->chunk_grp_bits;
+
+	if (dev->param.chunks_per_block < dev->chunk_grp_size) {
+		/* We have a problem because the soft delete won't work if
+		 * the chunk group size > chunks per block.
+		 * This can be remedied by using larger "virtual blocks".
+		 */
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR("yaffs: chunk group too large\n" TENDSTR)));
+
+		return YAFFS_FAIL;
+	}
+
+	/* OK, we've finished verifying the device, lets continue with initialisation */
+
+	/* More device initialisation */
+	dev->all_gcs = 0;
+	dev->passive_gc_count = 0;
+	dev->oldest_dirty_gc_count = 0;
+	dev->bg_gcs = 0;
+	dev->gc_block_finder = 0;
+	dev->buffered_block = -1;
+	dev->doing_buffered_block_rewrite = 0;
+	dev->n_deleted_files = 0;
+	dev->n_bg_deletions = 0;
+	dev->n_unlinked_files = 0;
+	dev->n_ecc_fixed = 0;
+	dev->n_ecc_unfixed = 0;
+	dev->n_tags_ecc_fixed = 0;
+	dev->n_tags_ecc_unfixed = 0;
+	dev->n_erase_failures = 0;
+	dev->n_erased_blocks = 0;
+	dev->gc_disable= 0;
+	dev->has_pending_prioritised_gc = 1; /* Assume the worst for now, will get fixed on first GC */
+	YINIT_LIST_HEAD(&dev->dirty_dirs);
+	dev->oldest_dirty_seq = 0;
+	dev->oldest_dirty_block = 0;
+
+	/* Initialise temporary buffers and caches. */
+	if (!yaffs_init_tmp_buffers(dev))
+		init_failed = 1;
+
+	dev->cache = NULL;
+	dev->gc_cleanup_list = NULL;
+
+
+	if (!init_failed &&
+	    dev->param.n_caches > 0) {
+		int i;
+		void *buf;
+		int cache_bytes = dev->param.n_caches * sizeof(yaffs_cache_t);
+
+		if (dev->param.n_caches > YAFFS_MAX_SHORT_OP_CACHES)
+			dev->param.n_caches = YAFFS_MAX_SHORT_OP_CACHES;
+
+		dev->cache =  YMALLOC(cache_bytes);
+
+		buf = (__u8 *) dev->cache;
+
+		if (dev->cache)
+			memset(dev->cache, 0, cache_bytes);
+
+		for (i = 0; i < dev->param.n_caches && buf; i++) {
+			dev->cache[i].object = NULL;
+			dev->cache[i].last_use = 0;
+			dev->cache[i].dirty = 0;
+			dev->cache[i].data = buf = YMALLOC_DMA(dev->param.total_bytes_per_chunk);
+		}
+		if (!buf)
+			init_failed = 1;
+
+		dev->cache_last_use = 0;
+	}
+
+	dev->cache_hits = 0;
+
+	if (!init_failed) {
+		dev->gc_cleanup_list = YMALLOC(dev->param.chunks_per_block * sizeof(__u32));
+		if (!dev->gc_cleanup_list)
+			init_failed = 1;
+	}
+
+	if (dev->param.is_yaffs2)
+		dev->param.use_header_file_size = 1;
+
+	if (!init_failed && !yaffs_init_blocks(dev))
+		init_failed = 1;
+
+	yaffs_init_tnodes_and_objs(dev);
+
+	if (!init_failed && !yaffs_create_initial_dir(dev))
+		init_failed = 1;
+
+
+	if (!init_failed) {
+		/* Now scan the flash. */
+		if (dev->param.is_yaffs2) {
+			if (yaffs2_checkpt_restore(dev)) {
+				yaffs_check_obj_details_loaded(dev->root_dir);
+				T(YAFFS_TRACE_ALWAYS,
+				  (TSTR("yaffs: restored from checkpoint" TENDSTR)));
+			} else {
+
+				/* Clean up the mess caused by an aborted checkpoint load
+				 * and scan backwards.
+				 */
+				yaffs_deinit_blocks(dev);
+
+				yaffs_deinit_tnodes_and_objs(dev);
+
+				dev->n_erased_blocks = 0;
+				dev->n_free_chunks = 0;
+				dev->alloc_block = -1;
+				dev->alloc_page = -1;
+				dev->n_deleted_files = 0;
+				dev->n_unlinked_files = 0;
+				dev->n_bg_deletions = 0;
+
+				if (!init_failed && !yaffs_init_blocks(dev))
+					init_failed = 1;
+
+				yaffs_init_tnodes_and_objs(dev);
+
+				if (!init_failed && !yaffs_create_initial_dir(dev))
+					init_failed = 1;
+
+				if (!init_failed && !yaffs2_scan_backwards(dev))
+					init_failed = 1;
+			}
+		} else if (!yaffs1_scan(dev))
+				init_failed = 1;
+
+		yaffs_strip_deleted_objs(dev);
+		yaffs_fix_hanging_objs(dev);
+		if(dev->param.empty_lost_n_found)
+			yaffs_empty_l_n_f(dev);
+	}
+
+	if (init_failed) {
+		/* Clean up the mess */
+		T(YAFFS_TRACE_TRACING,
+		  (TSTR("yaffs: yaffs_guts_initialise() aborted.\n" TENDSTR)));
+
+		yaffs_deinitialise(dev);
+		return YAFFS_FAIL;
+	}
+
+	/* Zero out stats */
+	dev->n_page_reads = 0;
+	dev->n_page_writes = 0;
+	dev->n_erasures = 0;
+	dev->n_gc_copies = 0;
+	dev->n_retired_writes = 0;
+
+	dev->n_retired_blocks = 0;
+
+	yaffs_verify_free_chunks(dev);
+	yaffs_verify_blocks(dev);
+
+	/* Clean up any aborted checkpoint data */
+	if(!dev->is_checkpointed && dev->blocks_in_checkpt > 0)
+		yaffs2_checkpt_invalidate(dev);
+
+	T(YAFFS_TRACE_TRACING,
+	  (TSTR("yaffs: yaffs_guts_initialise() done.\n" TENDSTR)));
+	return YAFFS_OK;
+
+}
+
+void yaffs_deinitialise(yaffs_dev_t *dev)
+{
+	if (dev->is_mounted) {
+		int i;
+
+		yaffs_deinit_blocks(dev);
+		yaffs_deinit_tnodes_and_objs(dev);
+		if (dev->param.n_caches > 0 &&
+		    dev->cache) {
+
+			for (i = 0; i < dev->param.n_caches; i++) {
+				if (dev->cache[i].data)
+					YFREE(dev->cache[i].data);
+				dev->cache[i].data = NULL;
+			}
+
+			YFREE(dev->cache);
+			dev->cache = NULL;
+		}
+
+		YFREE(dev->gc_cleanup_list);
+
+		for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
+			YFREE(dev->temp_buffer[i].buffer);
+
+		dev->is_mounted = 0;
+
+		if (dev->param.deinitialise_flash_fn)
+			dev->param.deinitialise_flash_fn(dev);
+	}
+}
+
+int yaffs_count_free_chunks(yaffs_dev_t *dev)
+{
+	int n_free=0;
+	int b;
+
+	yaffs_block_info_t *blk;
+
+	blk = dev->block_info;
+	for (b = dev->internal_start_block; b <= dev->internal_end_block; b++) {
+		switch (blk->block_state) {
+		case YAFFS_BLOCK_STATE_EMPTY:
+		case YAFFS_BLOCK_STATE_ALLOCATING:
+		case YAFFS_BLOCK_STATE_COLLECTING:
+		case YAFFS_BLOCK_STATE_FULL:
+			n_free +=
+			    (dev->param.chunks_per_block - blk->pages_in_use +
+			     blk->soft_del_pages);
+			break;
+		default:
+			break;
+		}
+		blk++;
+	}
+
+	return n_free;
+}
+
+int yaffs_get_n_free_chunks(yaffs_dev_t *dev)
+{
+	/* This is what we report to the outside world */
+
+	int n_free;
+	int n_dirty_caches;
+	int blocks_for_checkpt;
+	int i;
+
+#if 1
+	n_free = dev->n_free_chunks;
+#else
+	n_free = yaffs_count_free_chunks(dev);
+#endif
+
+	n_free += dev->n_deleted_files;
+
+	/* Now count the number of dirty chunks in the cache and subtract those */
+
+	for (n_dirty_caches = 0, i = 0; i < dev->param.n_caches; i++) {
+		if (dev->cache[i].dirty)
+			n_dirty_caches++;
+	}
+
+	n_free -= n_dirty_caches;
+
+	n_free -= ((dev->param.n_reserved_blocks + 1) * dev->param.chunks_per_block);
+
+	/* Now we figure out how much to reserve for the checkpoint and report that... */
+	blocks_for_checkpt = yaffs_calc_checkpt_blocks_required(dev);
+
+	n_free -= (blocks_for_checkpt * dev->param.chunks_per_block);
+
+	if (n_free < 0)
+		n_free = 0;
+
+	return n_free;
+
+}
+
+
+/*---------------------------------------- YAFFS test code ----------------------*/
+
+#define yaffs_check_struct(structure, syze, name) \
+	do { \
+		if (sizeof(structure) != syze) { \
+			T(YAFFS_TRACE_ALWAYS, (TSTR("%s should be %d but is %d\n" TENDSTR),\
+				name, syze, (int) sizeof(structure))); \
+			return YAFFS_FAIL; \
+		} \
+	} while (0)
+
+static int yaffs_check_structures(void)
+{
+/*      yaffs_check_struct(yaffs_tags_t,8,"yaffs_tags_t"); */
+/*      yaffs_check_struct(yaffs_tags_union_t,8,"yaffs_tags_union_t"); */
+/*      yaffs_check_struct(yaffs_spare,16,"yaffs_spare"); */
+/*	yaffs_check_struct(yaffs_tnode_t, 2 * YAFFS_NTNODES_LEVEL0, "yaffs_tnode_t"); */
+
+#ifndef CONFIG_YAFFS_WINCE
+	yaffs_check_struct(yaffs_obj_header, 512, "yaffs_obj_header");
+#endif
+	return YAFFS_OK;
+}
diff --git a/drivers/staging/yaffs2/yaffs_guts.h b/drivers/staging/yaffs2/yaffs_guts.h
new file mode 100644
index 0000000..2668b99
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_guts.h
@@ -0,0 +1,969 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_GUTS_H__
+#define __YAFFS_GUTS_H__
+
+#include "yportenv.h"
+#include "devextras.h"
+#include "yaffs_list.h"
+
+#define YAFFS_OK	1
+#define YAFFS_FAIL  0
+
+/* Give us a  Y=0x59,
+ * Give us an A=0x41,
+ * Give us an FF=0xFF
+ * Give us an S=0x53
+ * And what have we got...
+ */
+#define YAFFS_MAGIC			0x5941FF53
+
+#define YAFFS_NTNODES_LEVEL0	  	16
+#define YAFFS_TNODES_LEVEL0_BITS	4
+#define YAFFS_TNODES_LEVEL0_MASK	0xf
+
+#define YAFFS_NTNODES_INTERNAL 		(YAFFS_NTNODES_LEVEL0 / 2)
+#define YAFFS_TNODES_INTERNAL_BITS 	(YAFFS_TNODES_LEVEL0_BITS - 1)
+#define YAFFS_TNODES_INTERNAL_MASK	0x7
+#define YAFFS_TNODES_MAX_LEVEL		6
+
+#ifndef CONFIG_YAFFS_NO_YAFFS1
+#define YAFFS_BYTES_PER_SPARE		16
+#define YAFFS_BYTES_PER_CHUNK		512
+#define YAFFS_CHUNK_SIZE_SHIFT		9
+#define YAFFS_CHUNKS_PER_BLOCK		32
+#define YAFFS_BYTES_PER_BLOCK		(YAFFS_CHUNKS_PER_BLOCK*YAFFS_BYTES_PER_CHUNK)
+#endif
+
+#define YAFFS_MIN_YAFFS2_CHUNK_SIZE 	1024
+#define YAFFS_MIN_YAFFS2_SPARE_SIZE	32
+
+#define YAFFS_MAX_CHUNK_ID		0x000FFFFF
+
+
+#define YAFFS_ALLOCATION_NOBJECTS	100
+#define YAFFS_ALLOCATION_NTNODES	100
+#define YAFFS_ALLOCATION_NLINKS		100
+
+#define YAFFS_NOBJECT_BUCKETS		256
+
+
+#define YAFFS_OBJECT_SPACE		0x40000
+#define YAFFS_MAX_OBJECT_ID		(YAFFS_OBJECT_SPACE -1)
+
+#define YAFFS_CHECKPOINT_VERSION 	4
+
+#ifdef CONFIG_YAFFS_UNICODE
+#define YAFFS_MAX_NAME_LENGTH		127
+#define YAFFS_MAX_ALIAS_LENGTH		79
+#else
+#define YAFFS_MAX_NAME_LENGTH		255
+#define YAFFS_MAX_ALIAS_LENGTH		159
+#endif
+
+#define YAFFS_SHORT_NAME_LENGTH		15
+
+/* Some special object ids for pseudo objects */
+#define YAFFS_OBJECTID_ROOT		1
+#define YAFFS_OBJECTID_LOSTNFOUND	2
+#define YAFFS_OBJECTID_UNLINKED		3
+#define YAFFS_OBJECTID_DELETED		4
+
+/* Pseudo object ids for checkpointing */
+#define YAFFS_OBJECTID_SB_HEADER	0x10
+#define YAFFS_OBJECTID_CHECKPOINT_DATA	0x20
+#define YAFFS_SEQUENCE_CHECKPOINT_DATA  0x21
+
+
+#define YAFFS_MAX_SHORT_OP_CACHES	20
+
+#define YAFFS_N_TEMP_BUFFERS		6
+
+/* We limit the number attempts at sucessfully saving a chunk of data.
+ * Small-page devices have 32 pages per block; large-page devices have 64.
+ * Default to something in the order of 5 to 10 blocks worth of chunks.
+ */
+#define YAFFS_WR_ATTEMPTS		(5*64)
+
+/* Sequence numbers are used in YAFFS2 to determine block allocation order.
+ * The range is limited slightly to help distinguish bad numbers from good.
+ * This also allows us to perhaps in the future use special numbers for
+ * special purposes.
+ * EFFFFF00 allows the allocation of 8 blocks per second (~1Mbytes) for 15 years,
+ * and is a larger number than the lifetime of a 2GB device.
+ */
+#define YAFFS_LOWEST_SEQUENCE_NUMBER	0x00001000
+#define YAFFS_HIGHEST_SEQUENCE_NUMBER	0xEFFFFF00
+
+/* Special sequence number for bad block that failed to be marked bad */
+#define YAFFS_SEQUENCE_BAD_BLOCK	0xFFFF0000
+
+/* ChunkCache is used for short read/write operations.*/
+typedef struct {
+	struct yaffs_obj_s *object;
+	int chunk_id;
+	int last_use;
+	int dirty;
+	int n_bytes;		/* Only valid if the cache is dirty */
+	int locked;		/* Can't push out or flush while locked. */
+	__u8 *data;
+} yaffs_cache_t;
+
+
+
+/* Tags structures in RAM
+ * NB This uses bitfield. Bitfields should not straddle a u32 boundary otherwise
+ * the structure size will get blown out.
+ */
+
+#ifndef CONFIG_YAFFS_NO_YAFFS1
+typedef struct {
+	unsigned chunk_id:20;
+	unsigned serial_number:2;
+	unsigned n_bytes_lsb:10;
+	unsigned obj_id:18;
+	unsigned ecc:12;
+	unsigned n_bytes_msb:2;
+} yaffs_tags_t;
+
+typedef union {
+	yaffs_tags_t as_tags;
+	__u8 as_bytes[8];
+} yaffs_tags_union_t;
+
+#endif
+
+/* Stuff used for extended tags in YAFFS2 */
+
+typedef enum {
+	YAFFS_ECC_RESULT_UNKNOWN,
+	YAFFS_ECC_RESULT_NO_ERROR,
+	YAFFS_ECC_RESULT_FIXED,
+	YAFFS_ECC_RESULT_UNFIXED
+} yaffs_ecc_result;
+
+typedef enum {
+	YAFFS_OBJECT_TYPE_UNKNOWN,
+	YAFFS_OBJECT_TYPE_FILE,
+	YAFFS_OBJECT_TYPE_SYMLINK,
+	YAFFS_OBJECT_TYPE_DIRECTORY,
+	YAFFS_OBJECT_TYPE_HARDLINK,
+	YAFFS_OBJECT_TYPE_SPECIAL
+} yaffs_obj_type;
+
+#define YAFFS_OBJECT_TYPE_MAX YAFFS_OBJECT_TYPE_SPECIAL
+
+typedef struct {
+
+	unsigned validity1;
+	unsigned chunk_used;	/*  Status of the chunk: used or unused */
+	unsigned obj_id;	/* If 0 then this is not part of an object (unused) */
+	unsigned chunk_id;	/* If 0 then this is a header, else a data chunk */
+	unsigned n_bytes;	/* Only valid for data chunks */
+
+	/* The following stuff only has meaning when we read */
+	yaffs_ecc_result ecc_result;
+	unsigned block_bad;
+
+	/* YAFFS 1 stuff */
+	unsigned is_deleted;	/* The chunk is marked deleted */
+	unsigned serial_number;	/* Yaffs1 2-bit serial number */
+
+	/* YAFFS2 stuff */
+	unsigned seq_number;	/* The sequence number of this block */
+
+	/* Extra info if this is an object header (YAFFS2 only) */
+
+	unsigned extra_available;	/* There is extra info available if this is not zero */
+	unsigned extra_parent_id;	/* The parent object */
+	unsigned extra_is_shrink;	/* Is it a shrink header? */
+	unsigned extra_shadows;		/* Does this shadow another object? */
+
+	yaffs_obj_type extra_obj_type;	/* What object type? */
+
+	unsigned extra_length;		/* Length if it is a file */
+	unsigned extra_equiv_id;	/* Equivalent object Id if it is a hard link */
+
+	unsigned validty1;
+
+} yaffs_ext_tags;
+
+/* Spare structure for YAFFS1 */
+typedef struct {
+	__u8 tb0;
+	__u8 tb1;
+	__u8 tb2;
+	__u8 tb3;
+	__u8 page_status;	/* set to 0 to delete the chunk */
+	__u8 block_status;
+	__u8 tb4;
+	__u8 tb5;
+	__u8 ecc1[3];
+	__u8 tb6;
+	__u8 tb7;
+	__u8 ecc2[3];
+} yaffs_spare;
+
+/*Special structure for passing through to mtd */
+struct yaffs_nand_spare {
+	yaffs_spare spare;
+	int eccres1;
+	int eccres2;
+};
+
+/* Block data in RAM */
+
+typedef enum {
+	YAFFS_BLOCK_STATE_UNKNOWN = 0,
+
+	YAFFS_BLOCK_STATE_SCANNING,
+        /* Being scanned */
+
+	YAFFS_BLOCK_STATE_NEEDS_SCANNING,
+	/* The block might have something on it (ie it is allocating or full, perhaps empty)
+	 * but it needs to be scanned to determine its true state.
+	 * This state is only valid during scanning.
+	 * NB We tolerate empty because the pre-scanner might be incapable of deciding
+	 * However, if this state is returned on a YAFFS2 device, then we expect a sequence number
+	 */
+
+	YAFFS_BLOCK_STATE_EMPTY,
+	/* This block is empty */
+
+	YAFFS_BLOCK_STATE_ALLOCATING,
+	/* This block is partially allocated.
+	 * At least one page holds valid data.
+	 * This is the one currently being used for page
+	 * allocation. Should never be more than one of these.
+         * If a block is only partially allocated at mount it is treated as full.
+	 */
+
+	YAFFS_BLOCK_STATE_FULL,
+	/* All the pages in this block have been allocated.
+         * If a block was only partially allocated when mounted we treat
+         * it as fully allocated.
+	 */
+
+	YAFFS_BLOCK_STATE_DIRTY,
+	/* The block was full and now all chunks have been deleted.
+	 * Erase me, reuse me.
+	 */
+
+	YAFFS_BLOCK_STATE_CHECKPOINT,
+	/* This block is assigned to holding checkpoint data. */
+
+	YAFFS_BLOCK_STATE_COLLECTING,
+	/* This block is being garbage collected */
+
+	YAFFS_BLOCK_STATE_DEAD
+	/* This block has failed and is not in use */
+} yaffs_block_state_t;
+
+#define	YAFFS_NUMBER_OF_BLOCK_STATES (YAFFS_BLOCK_STATE_DEAD + 1)
+
+
+typedef struct {
+
+	int soft_del_pages:10;	/* number of soft deleted pages */
+	int pages_in_use:10;	/* number of pages in use */
+	unsigned block_state:4;	/* One of the above block states. NB use unsigned because enum is sometimes an int */
+	__u32 needs_retiring:1;	/* Data has failed on this block, need to get valid data off */
+				/* and retire the block. */
+	__u32 skip_erased_check:1; /* If this is set we can skip the erased check on this block */
+	__u32 gc_prioritise:1; 	/* An ECC check or blank check has failed on this block.
+				   It should be prioritised for GC */
+	__u32 chunk_error_strikes:3; /* How many times we've had ecc etc failures on this block and tried to reuse it */
+
+#ifdef CONFIG_YAFFS_YAFFS2
+	__u32 has_shrink_hdr:1; /* This block has at least one shrink object header */
+	__u32 seq_number;	 /* block sequence number for yaffs2 */
+#endif
+
+} yaffs_block_info_t;
+
+/* -------------------------- Object structure -------------------------------*/
+/* This is the object structure as stored on NAND */
+
+typedef struct {
+	yaffs_obj_type type;
+
+	/* Apply to everything  */
+	int parent_obj_id;
+	__u16 sum_no_longer_used;        /* checksum of name. No longer used */
+	YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
+
+	/* The following apply to directories, files, symlinks - not hard links */
+	__u32 yst_mode;         /* protection */
+
+#ifdef CONFIG_YAFFS_WINCE
+	__u32 not_for_wince[5];
+#else
+	__u32 yst_uid;
+	__u32 yst_gid;
+	__u32 yst_atime;
+	__u32 yst_mtime;
+	__u32 yst_ctime;
+#endif
+
+	/* File size  applies to files only */
+	int file_size;
+
+	/* Equivalent object id applies to hard links only. */
+	int equiv_id;
+
+	/* Alias is for symlinks only. */
+	YCHAR alias[YAFFS_MAX_ALIAS_LENGTH + 1];
+
+	__u32 yst_rdev;		/* device stuff for block and char devices (major/min) */
+
+#ifdef CONFIG_YAFFS_WINCE
+	__u32 win_ctime[2];
+	__u32 win_atime[2];
+	__u32 win_mtime[2];
+#else
+	__u32 room_to_grow[6];
+
+#endif
+	__u32 inband_shadowed_obj_id;
+	__u32 inband_is_shrink;
+
+	__u32 reserved[2];
+	int shadows_obj;	/* This object header shadows the specified object if > 0 */
+
+	/* is_shrink applies to object headers written when we shrink the file (ie resize) */
+	__u32 is_shrink;
+
+} yaffs_obj_header;
+
+/*--------------------------- Tnode -------------------------- */
+
+union yaffs_tnode_union {
+	union yaffs_tnode_union *internal[YAFFS_NTNODES_INTERNAL];
+
+};
+
+typedef union yaffs_tnode_union yaffs_tnode_t;
+
+
+/*------------------------  Object -----------------------------*/
+/* An object can be one of:
+ * - a directory (no data, has children links
+ * - a regular file (data.... not prunes :->).
+ * - a symlink [symbolic link] (the alias).
+ * - a hard link
+ */
+
+typedef struct {
+	__u32 file_size;
+	__u32 scanned_size;
+	__u32 shrink_size;
+	int top_level;
+	yaffs_tnode_t *top;
+} yaffs_file_s;
+
+typedef struct {
+	struct ylist_head children;     /* list of child links */
+	struct ylist_head dirty;	/* Entry for list of dirty directories */
+} yaffs_dir_s;
+
+typedef struct {
+	YCHAR *alias;
+} yaffs_symlink_t;
+
+typedef struct {
+	struct yaffs_obj_s *equiv_obj;
+	__u32 equiv_id;
+} yaffs_hard_link_s;
+
+typedef union {
+	yaffs_file_s file_variant;
+	yaffs_dir_s dir_variant;
+	yaffs_symlink_t symlink_variant;
+	yaffs_hard_link_s hardlink_variant;
+} yaffs_obj_variant;
+
+
+
+struct yaffs_obj_s {
+	__u8 deleted:1;		/* This should only apply to unlinked files. */
+	__u8 soft_del:1;	/* it has also been soft deleted */
+	__u8 unlinked:1;	/* An unlinked file. The file should be in the unlinked directory.*/
+	__u8 fake:1;		/* A fake object has no presence on NAND. */
+	__u8 rename_allowed:1;	/* Some objects are not allowed to be renamed. */
+	__u8 unlink_allowed:1;
+	__u8 dirty:1;		/* the object needs to be written to flash */
+	__u8 valid:1;		/* When the file system is being loaded up, this
+				 * object might be created before the data
+				 * is available (ie. file data records appear before the header).
+				 */
+	__u8 lazy_loaded:1;	/* This object has been lazy loaded and is missing some detail */
+
+	__u8 defered_free:1;	/* For Linux kernel. Object is removed from NAND, but is
+				 * still in the inode cache. Free of object is defered.
+				 * until the inode is released.
+				 */
+	__u8 being_created:1;	/* This object is still being created so skip some checks. */
+	__u8 is_shadowed:1;	/* This object is shadowed on the way to being renamed. */
+
+	__u8 xattr_known:1;	/* We know if this has object has xattribs or not. */
+	__u8 has_xattr:1;	/* This object has xattribs. Valid if xattr_known. */
+
+	__u8 serial;		/* serial number of chunk in NAND. Cached here */
+	__u16 sum;		/* sum of the name to speed searching */
+
+	struct yaffs_dev_s *my_dev;       /* The device I'm on */
+
+	struct ylist_head hash_link;     /* list of objects in this hash bucket */
+
+	struct ylist_head hard_links;    /* all the equivalent hard linked objects */
+
+	/* directory structure stuff */
+	/* also used for linking up the free list */
+	struct yaffs_obj_s *parent;
+	struct ylist_head siblings;
+
+	/* Where's my object header in NAND? */
+	int hdr_chunk;
+
+	int n_data_chunks;	/* Number of data chunks attached to the file. */
+
+	__u32 obj_id;		/* the object id value */
+
+	__u32 yst_mode;
+
+#ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
+	YCHAR short_name[YAFFS_SHORT_NAME_LENGTH + 1];
+#endif
+
+#ifdef CONFIG_YAFFS_WINCE
+	__u32 win_ctime[2];
+	__u32 win_mtime[2];
+	__u32 win_atime[2];
+#else
+	__u32 yst_uid;
+	__u32 yst_gid;
+	__u32 yst_atime;
+	__u32 yst_mtime;
+	__u32 yst_ctime;
+#endif
+
+	__u32 yst_rdev;
+
+	void *my_inode;
+
+	yaffs_obj_type variant_type;
+
+	yaffs_obj_variant variant;
+
+};
+
+typedef struct yaffs_obj_s yaffs_obj_t;
+
+typedef struct {
+	struct ylist_head list;
+	int count;
+} yaffs_obj_bucket;
+
+
+/* yaffs_checkpt_obj_t holds the definition of an object as dumped
+ * by checkpointing.
+ */
+
+typedef struct {
+	int struct_type;
+	__u32 obj_id;
+	__u32 parent_id;
+	int hdr_chunk;
+	yaffs_obj_type variant_type:3;
+	__u8 deleted:1;
+	__u8 soft_del:1;
+	__u8 unlinked:1;
+	__u8 fake:1;
+	__u8 rename_allowed:1;
+	__u8 unlink_allowed:1;
+	__u8 serial;
+
+	int n_data_chunks;
+	__u32 size_or_equiv_obj;
+} yaffs_checkpt_obj_t;
+
+/*--------------------- Temporary buffers ----------------
+ *
+ * These are chunk-sized working buffers. Each device has a few
+ */
+
+typedef struct {
+	__u8 *buffer;
+	int line;	/* track from whence this buffer was allocated */
+	int max_line;
+} yaffs_buffer_t;
+
+/*----------------- Device ---------------------------------*/
+
+
+struct yaffs_param_s {
+	const YCHAR *name;
+
+	/*
+         * Entry parameters set up way early. Yaffs sets up the rest.
+         * The structure should be zeroed out before use so that unused
+         * and defualt values are zero.
+         */
+
+	int inband_tags;          /* Use unband tags */
+	__u32 total_bytes_per_chunk; /* Should be >= 512, does not need to be a power of 2 */
+	int chunks_per_block;	/* does not need to be a power of 2 */
+	int spare_bytes_per_chunk;	/* spare area size */
+	int start_block;		/* Start block we're allowed to use */
+	int end_block;		/* End block we're allowed to use */
+	int n_reserved_blocks;	/* We want this tuneable so that we can reduce */
+				/* reserved blocks on NOR and RAM. */
+
+
+	int n_caches;	/* If <= 0, then short op caching is disabled, else
+				 * the number of short op caches (don't use too many).
+                                 * 10 to 20 is a good bet.
+				 */
+	int use_nand_ecc;		/* Flag to decide whether or not to use NANDECC on data (yaffs1) */
+	int no_tags_ecc;		/* Flag to decide whether or not to do ECC on packed tags (yaffs2) */ 
+
+	int is_yaffs2;           /* Use yaffs2 mode on this device */
+
+	int empty_lost_n_found;  /* Auto-empty lost+found directory on mount */
+
+	int refresh_period;	/* How often we should check to do a block refresh */
+
+	/* Checkpoint control. Can be set before or after initialisation */
+	__u8 skip_checkpt_rd;
+	__u8 skip_checkpt_wr;
+
+	int enable_xattr;	/* Enable xattribs */
+
+	/* NAND access functions (Must be set before calling YAFFS)*/
+
+	int (*write_chunk_fn) (struct yaffs_dev_s *dev,
+					int nand_chunk, const __u8 *data,
+					const yaffs_spare *spare);
+	int (*read_chunk_fn) (struct yaffs_dev_s *dev,
+					int nand_chunk, __u8 *data,
+					yaffs_spare *spare);
+	int (*erase_fn) (struct yaffs_dev_s *dev,
+					int flash_block);
+	int (*initialise_flash_fn) (struct yaffs_dev_s *dev);
+	int (*deinitialise_flash_fn) (struct yaffs_dev_s *dev);
+
+#ifdef CONFIG_YAFFS_YAFFS2
+	int (*write_chunk_tags_fn) (struct yaffs_dev_s *dev,
+					 int nand_chunk, const __u8 *data,
+					 const yaffs_ext_tags *tags);
+	int (*read_chunk_tags_fn) (struct yaffs_dev_s *dev,
+					  int nand_chunk, __u8 *data,
+					  yaffs_ext_tags *tags);
+	int (*bad_block_fn) (struct yaffs_dev_s *dev, int block_no);
+	int (*query_block_fn) (struct yaffs_dev_s *dev, int block_no,
+			       yaffs_block_state_t *state, __u32 *seq_number);
+#endif
+
+	/* The remove_obj_fn function must be supplied by OS flavours that
+	 * need it.
+         * yaffs direct uses it to implement the faster readdir.
+         * Linux uses it to protect the directory during unlocking.
+	 */
+	void (*remove_obj_fn)(struct yaffs_obj_s *obj);
+
+	/* Callback to mark the superblock dirty */
+	void (*sb_dirty_fn)(struct yaffs_dev_s *dev);
+	
+	/*  Callback to control garbage collection. */
+	unsigned (*gc_control)(struct yaffs_dev_s *dev);
+
+        /* Debug control flags. Don't use unless you know what you're doing */
+	int use_header_file_size;	/* Flag to determine if we should use file sizes from the header */
+	int disable_lazy_load;	/* Disable lazy loading on this device */
+	int wide_tnodes_disabled; /* Set to disable wide tnodes */
+	int disable_soft_del;  /* yaffs 1 only: Set to disable the use of softdeletion. */
+	
+	int defered_dir_update; /* Set to defer directory updates */
+
+#ifdef CONFIG_YAFFS_AUTO_UNICODE
+	int auto_unicode;
+#endif
+	int always_check_erased; /* Force chunk erased check always on */
+};
+
+typedef struct yaffs_param_s yaffs_param_t;
+
+struct yaffs_dev_s {
+	struct yaffs_param_s param;
+
+        /* Context storage. Holds extra OS specific data for this device */
+
+	void *os_context;
+	void *driver_context;
+
+	struct ylist_head dev_list;
+
+	/* Runtime parameters. Set up by YAFFS. */
+	int data_bytes_per_chunk;	
+
+        /* Non-wide tnode stuff */
+	__u16 chunk_grp_bits;	/* Number of bits that need to be resolved if
+                                 * the tnodes are not wide enough.
+                                 */
+	__u16 chunk_grp_size;	/* == 2^^chunk_grp_bits */
+
+	/* Stuff to support wide tnodes */
+	__u32 tnode_width;
+	__u32 tnode_mask;
+	__u32 tnode_size;
+
+	/* Stuff for figuring out file offset to chunk conversions */
+	__u32 chunk_shift; /* Shift value */
+	__u32 chunk_div;   /* Divisor after shifting: 1 for power-of-2 sizes */
+	__u32 chunk_mask;  /* Mask to use for power-of-2 case */
+
+
+
+	int is_mounted;
+	int read_only;
+	int is_checkpointed;
+
+
+	/* Stuff to support block offsetting to support start block zero */
+	int internal_start_block;
+	int internal_end_block;
+	int block_offset;
+	int chunk_offset;
+
+
+	/* Runtime checkpointing stuff */
+	int checkpt_page_seq;   /* running sequence number of checkpoint pages */
+	int checkpt_byte_count;
+	int checkpt_byte_offs;
+	__u8 *checkpt_buffer;
+	int checkpt_open_write;
+	int blocks_in_checkpt;
+	int checkpt_cur_chunk;
+	int checkpt_cur_block;
+	int checkpt_next_block;
+	int *checkpt_block_list;
+	int checkpt_max_blocks;
+	__u32 checkpt_sum;
+	__u32 checkpt_xor;
+
+	int checkpoint_blocks_required; /* Number of blocks needed to store current checkpoint set */
+
+	/* Block Info */
+	yaffs_block_info_t *block_info;
+	__u8 *chunk_bits;	/* bitmap of chunks in use */
+	unsigned block_info_alt:1;	/* was allocated using alternative strategy */
+	unsigned chunk_bits_alt:1;	/* was allocated using alternative strategy */
+	int chunk_bit_stride;	/* Number of bytes of chunk_bits per block.
+				 * Must be consistent with chunks_per_block.
+				 */
+
+	int n_erased_blocks;
+	int alloc_block;	/* Current block being allocated off */
+	__u32 alloc_page;
+	int alloc_block_finder;	/* Used to search for next allocation block */
+
+	/* Object and Tnode memory management */
+	void *allocator;
+	int n_obj;
+	int n_tnodes;
+
+	int n_hardlinks;
+
+	yaffs_obj_bucket obj_bucket[YAFFS_NOBJECT_BUCKETS];
+	__u32 bucket_finder;
+
+	int n_free_chunks;
+
+	/* Garbage collection control */
+	__u32 *gc_cleanup_list;	/* objects to delete at the end of a GC. */
+	__u32 n_clean_ups;
+
+	unsigned has_pending_prioritised_gc; /* We think this device might have pending prioritised gcs */
+	unsigned gc_disable;
+	unsigned gc_block_finder;
+	unsigned gc_dirtiest;
+	unsigned gc_pages_in_use;
+	unsigned gc_not_done;
+	unsigned gc_block;
+	unsigned gc_chunk;
+	unsigned gc_skip;
+
+	/* Special directories */
+	yaffs_obj_t *root_dir;
+	yaffs_obj_t *lost_n_found;
+
+	/* Buffer areas for storing data to recover from write failures TODO
+	 *      __u8            buffered_data[YAFFS_CHUNKS_PER_BLOCK][YAFFS_BYTES_PER_CHUNK];
+	 *      yaffs_spare buffered_spare[YAFFS_CHUNKS_PER_BLOCK];
+	 */
+
+	int buffered_block;	/* Which block is buffered here? */
+	int doing_buffered_block_rewrite;
+
+	yaffs_cache_t *cache;
+	int cache_last_use;
+
+	/* Stuff for background deletion and unlinked files.*/
+	yaffs_obj_t *unlinked_dir;	/* Directory where unlinked and deleted files live. */
+	yaffs_obj_t *del_dir;	/* Directory where deleted objects are sent to disappear. */
+	yaffs_obj_t *unlinked_deletion;	/* Current file being background deleted.*/
+	int n_deleted_files;		/* Count of files awaiting deletion;*/
+	int n_unlinked_files;		/* Count of unlinked files. */
+	int n_bg_deletions;	/* Count of background deletions. */
+
+	/* Temporary buffer management */
+	yaffs_buffer_t temp_buffer[YAFFS_N_TEMP_BUFFERS];
+	int max_temp;
+	int temp_in_use;
+	int unmanaged_buffer_allocs;
+	int unmanaged_buffer_deallocs;
+
+	/* yaffs2 runtime stuff */
+	unsigned seq_number;	/* Sequence number of currently allocating block */
+	unsigned oldest_dirty_seq;
+	unsigned oldest_dirty_block;
+
+	/* Block refreshing */
+	int refresh_skip;	/* A skip down counter. Refresh happens when this gets to zero. */
+
+	/* Dirty directory handling */
+	struct ylist_head dirty_dirs; /* List of dirty directories */
+
+
+	/* Statistcs */
+	__u32 n_page_writes;
+	__u32 n_page_reads;
+	__u32 n_erasures;
+	__u32 n_erase_failures;
+	__u32 n_gc_copies;
+	__u32 all_gcs;
+	__u32 passive_gc_count;
+	__u32 oldest_dirty_gc_count;
+	__u32 n_gc_blocks;
+	__u32 bg_gcs;
+	__u32 n_retired_writes;
+	__u32 n_retired_blocks;
+	__u32 n_ecc_fixed;
+	__u32 n_ecc_unfixed;
+	__u32 n_tags_ecc_fixed;
+	__u32 n_tags_ecc_unfixed;
+	__u32 n_deletions;
+	__u32 n_unmarked_deletions;
+	__u32 refresh_count;
+	__u32 cache_hits;
+
+};
+
+typedef struct yaffs_dev_s yaffs_dev_t;
+
+/* The static layout of block usage etc is stored in the super block header */
+typedef struct {
+	int StructType;
+	int version;
+	int checkpt_start_block;
+	int checkpt_end_block;
+	int start_block;
+	int end_block;
+	int rfu[100];
+} yaffs_sb_header;
+
+/* The CheckpointDevice structure holds the device information that changes at runtime and
+ * must be preserved over unmount/mount cycles.
+ */
+typedef struct {
+	int struct_type;
+	int n_erased_blocks;
+	int alloc_block;	/* Current block being allocated off */
+	__u32 alloc_page;
+	int n_free_chunks;
+
+	int n_deleted_files;		/* Count of files awaiting deletion;*/
+	int n_unlinked_files;		/* Count of unlinked files. */
+	int n_bg_deletions;	/* Count of background deletions. */
+
+	/* yaffs2 runtime stuff */
+	unsigned seq_number;	/* Sequence number of currently allocating block */
+
+} yaffs_checkpt_dev_t;
+
+
+typedef struct {
+	int struct_type;
+	__u32 magic;
+	__u32 version;
+	__u32 head;
+} yaffs_checkpt_validty_t;
+
+
+struct yaffs_shadow_fixer_s {
+	int obj_id;
+	int shadowed_id;
+	struct yaffs_shadow_fixer_s *next;
+};
+
+/* Structure for doing xattr modifications */
+typedef struct {
+	int set; /* If 0 then this is a deletion */
+	const YCHAR *name;
+	const void *data;
+	int size;
+	int flags;
+	int result;
+}yaffs_xattr_mod;
+
+
+/*----------------------- YAFFS Functions -----------------------*/
+
+int yaffs_guts_initialise(yaffs_dev_t *dev);
+void yaffs_deinitialise(yaffs_dev_t *dev);
+
+int yaffs_get_n_free_chunks(yaffs_dev_t *dev);
+
+int yaffs_rename_obj(yaffs_obj_t *old_dir, const YCHAR *old_name,
+		       yaffs_obj_t *new_dir, const YCHAR *new_name);
+
+int yaffs_unlinker(yaffs_obj_t *dir, const YCHAR *name);
+int yaffs_del_obj(yaffs_obj_t *obj);
+
+int yaffs_get_obj_name(yaffs_obj_t *obj, YCHAR *name, int buffer_size);
+int yaffs_get_obj_length(yaffs_obj_t *obj);
+int yaffs_get_obj_inode(yaffs_obj_t *obj);
+unsigned yaffs_get_obj_type(yaffs_obj_t *obj);
+int yaffs_get_obj_link_count(yaffs_obj_t *obj);
+
+int yaffs_set_attribs(yaffs_obj_t *obj, struct iattr *attr);
+int yaffs_get_attribs(yaffs_obj_t *obj, struct iattr *attr);
+
+/* File operations */
+int yaffs_file_rd(yaffs_obj_t *obj, __u8 *buffer, loff_t offset,
+				int n_bytes);
+int yaffs_wr_file(yaffs_obj_t *obj, const __u8 *buffer, loff_t offset,
+				int n_bytes, int write_trhrough);
+int yaffs_resize_file(yaffs_obj_t *obj, loff_t new_size);
+
+yaffs_obj_t *yaffs_create_file(yaffs_obj_t *parent, const YCHAR *name,
+				__u32 mode, __u32 uid, __u32 gid);
+
+int yaffs_flush_file(yaffs_obj_t *obj, int update_time, int data_sync);
+
+/* Flushing and checkpointing */
+void yaffs_flush_whole_cache(yaffs_dev_t *dev);
+
+int yaffs_checkpoint_save(yaffs_dev_t *dev);
+int yaffs_checkpoint_restore(yaffs_dev_t *dev);
+
+/* Directory operations */
+yaffs_obj_t *yaffs_create_dir(yaffs_obj_t *parent, const YCHAR *name,
+				__u32 mode, __u32 uid, __u32 gid);
+yaffs_obj_t *yaffs_find_by_name(yaffs_obj_t *the_dir, const YCHAR *name);
+int yaffs_ApplyToDirectoryChildren(yaffs_obj_t *the_dir,
+				   int (*fn) (yaffs_obj_t *));
+
+yaffs_obj_t *yaffs_find_by_number(yaffs_dev_t *dev, __u32 number);
+
+/* Link operations */
+yaffs_obj_t *yaffs_link_obj(yaffs_obj_t *parent, const YCHAR *name,
+			 yaffs_obj_t *equiv_obj);
+
+yaffs_obj_t *yaffs_get_equivalent_obj(yaffs_obj_t *obj);
+
+/* Symlink operations */
+yaffs_obj_t *yaffs_create_symlink(yaffs_obj_t *parent, const YCHAR *name,
+				 __u32 mode, __u32 uid, __u32 gid,
+				 const YCHAR *alias);
+YCHAR *yaffs_get_symlink_alias(yaffs_obj_t *obj);
+
+/* Special inodes (fifos, sockets and devices) */
+yaffs_obj_t *yaffs_create_special(yaffs_obj_t *parent, const YCHAR *name,
+				 __u32 mode, __u32 uid, __u32 gid, __u32 rdev);
+
+
+int yaffs_set_xattrib(yaffs_obj_t *obj, const YCHAR *name, const void * value, int size, int flags);
+int yaffs_get_xattrib(yaffs_obj_t *obj, const YCHAR *name, void *value, int size);
+int yaffs_list_xattrib(yaffs_obj_t *obj, char *buffer, int size);
+int yaffs_remove_xattrib(yaffs_obj_t *obj, const YCHAR *name);
+
+/* Special directories */
+yaffs_obj_t *yaffs_root(yaffs_dev_t *dev);
+yaffs_obj_t *yaffs_lost_n_found(yaffs_dev_t *dev);
+
+#ifdef CONFIG_YAFFS_WINCE
+/* CONFIG_YAFFS_WINCE special stuff */
+void yfsd_win_file_time_now(__u32 target[2]);
+#endif
+
+void yaffs_handle_defered_free(yaffs_obj_t *obj);
+
+void yaffs_update_dirty_dirs(yaffs_dev_t *dev);
+
+int yaffs_bg_gc(yaffs_dev_t *dev, unsigned urgency);
+
+/* Debug dump  */
+int yaffs_dump_obj(yaffs_obj_t *obj);
+
+void yaffs_guts_test(yaffs_dev_t *dev);
+
+/* A few useful functions to be used within the core files*/
+void yaffs_chunk_del(yaffs_dev_t *dev, int chunk_id, int mark_flash, int lyn);
+int yaffs_check_ff(__u8 *buffer, int n_bytes);
+void yaffs_handle_chunk_error(yaffs_dev_t *dev, yaffs_block_info_t *bi);
+
+__u8 *yaffs_get_temp_buffer(yaffs_dev_t *dev, int line_no);
+void yaffs_release_temp_buffer(yaffs_dev_t *dev, __u8 *buffer, int line_no);
+
+yaffs_obj_t *yaffs_find_or_create_by_number(yaffs_dev_t *dev,
+					        int number,
+					        yaffs_obj_type type);
+int yaffs_put_chunk_in_file(yaffs_obj_t *in, int inode_chunk,
+			        int nand_chunk, int in_scan);
+void yaffs_set_obj_name(yaffs_obj_t *obj, const YCHAR *name);
+void yaffs_set_obj_name_from_oh(yaffs_obj_t *obj, const yaffs_obj_header *oh);
+void yaffs_add_obj_to_dir(yaffs_obj_t *directory,
+					yaffs_obj_t *obj);
+YCHAR *yaffs_clone_str(const YCHAR *str);
+void yaffs_link_fixup(yaffs_dev_t *dev, yaffs_obj_t *hard_list);
+void yaffs_block_became_dirty(yaffs_dev_t *dev, int block_no);
+int yaffs_update_oh(yaffs_obj_t *in, const YCHAR *name,
+				int force, int is_shrink, int shadows,
+                                yaffs_xattr_mod *xop);
+void yaffs_handle_shadowed_obj(yaffs_dev_t *dev, int obj_id,
+				int backward_scanning);
+int yaffs_check_alloc_available(yaffs_dev_t *dev, int n_chunks);
+yaffs_tnode_t *yaffs_get_tnode(yaffs_dev_t *dev);
+yaffs_tnode_t *yaffs_add_find_tnode_0(yaffs_dev_t *dev,
+					yaffs_file_s *file_struct,
+					__u32 chunk_id,
+					yaffs_tnode_t *passed_tn);
+
+int yaffs_do_file_wr(yaffs_obj_t *in, const __u8 *buffer, loff_t offset,
+			int n_bytes, int write_trhrough);
+void yaffs_resize_file_down( yaffs_obj_t *obj, loff_t new_size);
+void yaffs_skip_rest_of_block(yaffs_dev_t *dev);
+
+int yaffs_count_free_chunks(yaffs_dev_t *dev);
+
+yaffs_tnode_t *yaffs_find_tnode_0(yaffs_dev_t *dev,
+				yaffs_file_s *file_struct,
+				__u32 chunk_id);
+
+__u32 yaffs_get_group_base(yaffs_dev_t *dev, yaffs_tnode_t *tn, unsigned pos);
+
+#endif
-- 
1.7.3.2.146.gca209

Re: [PATCH 10/29] Staging: yaffs2: yaffs_guts: Add files

[Jesper Juhl]

On Mon, 1 Nov 2010, Tracey Dent wrote:

> Adding files to yaffs2 directory.
>    
> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> ---
>  drivers/staging/yaffs2/yaffs_guts.c | 5544 
+++++++++++++++++++++++++++++++++++
>  drivers/staging/yaffs2/yaffs_guts.h |  969 ++++++
>  2 files changed, 6513 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/yaffs2/yaffs_guts.c
>  create mode 100644 drivers/staging/yaffs2/yaffs_guts.h
>  
> diff --git a/drivers/staging/yaffs2/yaffs_guts.c 
b/drivers/staging/yaffs2/yaffs_guts.c
> new file mode 100644
> index 0000000..eea828a
> --- /dev/null
> +++ b/drivers/staging/yaffs2/yaffs_guts.c
> @@ -0,0 +1,5544 @@
> +/*
> + * YAFFS: Yet Another Flash File System. A NAND-flash specific file 
system.
> + *
> + * Copyright (C) 2002-2010 Aleph One Ltd.
> + *   for Toby Churchill Ltd and Brightstar Engineering
> + *
> + * Created by Charles Manning <charles@aleph1.co.uk>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include "yportenv.h"
> +#include "yaffs_trace.h"
> +
> +#include "yaffs_guts.h"
> +#include "yaffs_tagsvalidity.h" 
> +#include "yaffs_getblockinfo.h"
> +
> +#include "yaffs_tagscompat.h"
> +
> +#include "yaffs_nand.h"

   ^--- here

> +
> +#include "yaffs_yaffs1.h"
> +#include "yaffs_yaffs2.h"
> +#include "yaffs_bitmap.h"
> +#include "yaffs_verify.h"
> +
> +#include "yaffs_nand.h"

   ^--- and here

duplicate inclusion of "yaffs_nand.h" header.


-- 
Jesper Juhl <jj@chaosbits.net>             http://www.chaosbits.net/
Plain text mails only, please      http://www.expita.com/nomime.html
Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html

[PATCH 11/29] Staging: yaffs2: yaffs_linux.h: Add file

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_linux.h |   43 ++++++++++++++++++++++++++++++++++
 1 files changed, 43 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_linux.h

diff --git a/drivers/staging/yaffs2/yaffs_linux.h b/drivers/staging/yaffs2/yaffs_linux.h
new file mode 100644
index 0000000..a8e3f85
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_linux.h
@@ -0,0 +1,43 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_LINUX_H__
+#define __YAFFS_LINUX_H__
+
+#include "devextras.h"
+#include "yportenv.h"
+
+struct yaffs_linux_context {
+	struct ylist_head	context_list; /* List of these we have mounted */
+	struct yaffs_dev_s *dev;
+	struct super_block * super;
+	struct task_struct *bg_thread; /* Background thread for this device */
+	int bg_running;
+        struct semaphore gross_lock;     /* Gross locking semaphore */
+	__u8 *spare_buffer;      /* For mtdif2 use. Don't know the size of the buffer
+				 * at compile time so we have to allocate it.
+				 */
+	struct ylist_head search_contexts;
+	void (*put_super_fn)(struct super_block *sb);
+
+	struct task_struct *readdir_process;
+	unsigned mount_id;
+};
+
+#define yaffs_dev_to_lc(dev) ((struct yaffs_linux_context *)((dev)->os_context))
+#define yaffs_dev_to_mtd(dev) ((struct mtd_info *)((dev)->driver_context))
+
+#endif
+
-- 
1.7.3.2.146.gca209

[PATCH 12/29] Staging: yaffs2: yaffs_list.h: add file

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_list.h |  127 +++++++++++++++++++++++++++++++++++
 1 files changed, 127 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_list.h

diff --git a/drivers/staging/yaffs2/yaffs_list.h b/drivers/staging/yaffs2/yaffs_list.h
new file mode 100644
index 0000000..145a1c5
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_list.h
@@ -0,0 +1,127 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+/*
+ * This file is just holds extra declarations of macros that would normally
+ * be providesd in the Linux kernel. These macros have been written from
+ * scratch but are functionally equivalent to the Linux ones.
+ *
+ */
+
+#ifndef __YAFFS_LIST_H__
+#define __YAFFS_LIST_H__
+
+
+#include "yportenv.h"
+
+/*
+ * This is a simple doubly linked list implementation that matches the
+ * way the Linux kernel doubly linked list implementation works.
+ */
+
+struct ylist_head {
+	struct ylist_head *next; /* next in chain */
+	struct ylist_head *prev; /* previous in chain */
+};
+
+
+/* Initialise a static list */
+#define YLIST_HEAD(name) \
+struct ylist_head name = { &(name), &(name)}
+
+
+
+/* Initialise a list head to an empty list */
+#define YINIT_LIST_HEAD(p) \
+do { \
+	(p)->next = (p);\
+	(p)->prev = (p); \
+} while (0)
+
+
+/* Add an element to a list */
+static Y_INLINE void ylist_add(struct ylist_head *new_entry,
+				struct ylist_head *list)
+{
+	struct ylist_head *list_next = list->next;
+
+	list->next = new_entry;
+	new_entry->prev = list;
+	new_entry->next = list_next;
+	list_next->prev = new_entry;
+
+}
+
+static Y_INLINE void ylist_add_tail(struct ylist_head *new_entry,
+				 struct ylist_head *list)
+{
+	struct ylist_head *list_prev = list->prev;
+
+	list->prev = new_entry;
+	new_entry->next = list;
+	new_entry->prev = list_prev;
+	list_prev->next = new_entry;
+
+}
+
+
+/* Take an element out of its current list, with or without
+ * reinitialising the links.of the entry*/
+static Y_INLINE void ylist_del(struct ylist_head *entry)
+{
+	struct ylist_head *list_next = entry->next;
+	struct ylist_head *list_prev = entry->prev;
+
+	list_next->prev = list_prev;
+	list_prev->next = list_next;
+
+}
+
+static Y_INLINE void ylist_del_init(struct ylist_head *entry)
+{
+	ylist_del(entry);
+	entry->next = entry->prev = entry;
+}
+
+
+/* Test if the list is empty */
+static Y_INLINE int ylist_empty(struct ylist_head *entry)
+{
+	return (entry->next == entry);
+}
+
+
+/* ylist_entry takes a pointer to a list entry and offsets it to that
+ * we can find a pointer to the object it is embedded in.
+ */
+
+
+#define ylist_entry(entry, type, member) \
+	((type *)((char *)(entry)-(unsigned long)(&((type *)NULL)->member)))
+
+
+/* ylist_for_each and list_for_each_safe  iterate over lists.
+ * ylist_for_each_safe uses temporary storage to make the list delete safe
+ */
+
+#define ylist_for_each(itervar, list) \
+	for (itervar = (list)->next; itervar != (list); itervar = itervar->next)
+
+#define ylist_for_each_safe(itervar, save_var, list) \
+	for (itervar = (list)->next, save_var = (list)->next->next; \
+		itervar != (list); itervar = save_var, save_var = save_var->next)
+
+
+#endif
-- 
1.7.3.2.146.gca209

Re: [PATCH 12/29] Staging: yaffs2: yaffs_list.h: add file

[Pekka Enberg]

On Mon, Nov 1, 2010 at 8:41 PM, Tracey Dent <tdent48227@gmail.com> wrote:
> Adding files to yaffs2 directory.
>
> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> ---
>  drivers/staging/yaffs2/yaffs_list.h |  127 +++++++++++++++++++++++++++++++++++
>  1 files changed, 127 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/yaffs2/yaffs_list.h
>
> diff --git a/drivers/staging/yaffs2/yaffs_list.h b/drivers/staging/yaffs2/yaffs_list.h
> new file mode 100644
> index 0000000..145a1c5
> --- /dev/null
> +++ b/drivers/staging/yaffs2/yaffs_list.h
> +/*
> + * This file is just holds extra declarations of macros that would normally
> + * be providesd in the Linux kernel. These macros have been written from
> + * scratch but are functionally equivalent to the Linux ones.
> + *
> + */

This header needs to die.
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[PATCH 13/29] Staging: yaffs2: yaffs_mtdif: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_mtdif.c |   56 ++++++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_mtdif.h |   27 ++++++++++++++++
 2 files changed, 83 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_mtdif.c
 create mode 100644 drivers/staging/yaffs2/yaffs_mtdif.h

diff --git a/drivers/staging/yaffs2/yaffs_mtdif.c b/drivers/staging/yaffs2/yaffs_mtdif.c
new file mode 100644
index 0000000..4fd8994
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_mtdif.c
@@ -0,0 +1,56 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yportenv.h"
+
+
+#include "yaffs_mtdif.h"
+
+#include "linux/mtd/mtd.h"
+#include "linux/types.h"
+#include "linux/time.h"
+#include "linux/mtd/nand.h"
+
+#include "yaffs_linux.h"
+
+int nandmtd_erase_block(yaffs_dev_t *dev, int block_no)
+{
+	struct mtd_info *mtd = yaffs_dev_to_mtd(dev);
+	__u32 addr =
+	    ((loff_t) block_no) * dev->param.total_bytes_per_chunk
+		* dev->param.chunks_per_block;
+	struct erase_info ei;
+	
+	int retval = 0;
+
+	ei.mtd = mtd;
+	ei.addr = addr;
+	ei.len = dev->param.total_bytes_per_chunk * dev->param.chunks_per_block;
+	ei.time = 1000;
+	ei.retries = 2;
+	ei.callback = NULL;
+	ei.priv = (u_long) dev;
+
+	retval = mtd->erase(mtd, &ei);
+
+	if (retval == 0)
+		return YAFFS_OK;
+	else
+		return YAFFS_FAIL;
+}
+
+int nandmtd_initialise(yaffs_dev_t *dev)
+{
+	return YAFFS_OK;
+}
+
diff --git a/drivers/staging/yaffs2/yaffs_mtdif.h b/drivers/staging/yaffs2/yaffs_mtdif.h
new file mode 100644
index 0000000..919d354
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_mtdif.h
@@ -0,0 +1,27 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_MTDIF_H__
+#define __YAFFS_MTDIF_H__
+
+#include "yaffs_guts.h"
+
+#if (MTD_VERSION_CODE < MTD_VERSION(2, 6, 18))
+extern struct nand_oobinfo yaffs_oobinfo;
+extern struct nand_oobinfo yaffs_noeccinfo;
+#endif
+int nandmtd_erase_block(yaffs_dev_t *dev, int block_no);
+int nandmtd_initialise(yaffs_dev_t *dev);
+#endif
-- 
1.7.3.2.146.gca209

[PATCH 14/29] Staging: yaffs2: yaffs_mtdif1: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_mtdif1.c |  362 +++++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_mtdif1.h |   28 +++
 2 files changed, 390 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_mtdif1.c
 create mode 100644 drivers/staging/yaffs2/yaffs_mtdif1.h

diff --git a/drivers/staging/yaffs2/yaffs_mtdif1.c b/drivers/staging/yaffs2/yaffs_mtdif1.c
new file mode 100644
index 0000000..6380999
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_mtdif1.c
@@ -0,0 +1,362 @@
+/*
+ * YAFFS: Yet another FFS. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/*
+ * This module provides the interface between yaffs_nand.c and the
+ * MTD API.  This version is used when the MTD interface supports the
+ * 'mtd_oob_ops' style calls to read_oob and write_oob, circa 2.6.17,
+ * and we have small-page NAND device.
+ *
+ * These functions are invoked via function pointers in yaffs_nand.c.
+ * This replaces functionality provided by functions in yaffs_mtdif.c
+ * and the yaffs_tags_tCompatability functions in yaffs_tagscompat.c that are
+ * called in yaffs_mtdif.c when the function pointers are NULL.
+ * We assume the MTD layer is performing ECC (use_nand_ecc is true).
+ */
+
+#include "yportenv.h"
+#include "yaffs_trace.h"
+#include "yaffs_guts.h"
+#include "yaffs_packedtags1.h"
+#include "yaffs_tagscompat.h"	/* for yaffs_calc_tags_ecc */
+#include "yaffs_linux.h"
+
+#include "linux/kernel.h"
+#include "linux/version.h"
+#include "linux/types.h"
+#include "linux/mtd/mtd.h"
+
+/* Don't compile this module if we don't have MTD's mtd_oob_ops interface */
+#if (MTD_VERSION_CODE > MTD_VERSION(2, 6, 17))
+
+#ifndef CONFIG_YAFFS_9BYTE_TAGS
+# define YTAG1_SIZE 8
+#else
+# define YTAG1_SIZE 9
+#endif
+
+#if 0
+/* Use the following nand_ecclayout with MTD when using
+ * CONFIG_YAFFS_9BYTE_TAGS and the older on-NAND tags layout.
+ * If you have existing Yaffs images and the byte order differs from this,
+ * adjust 'oobfree' to match your existing Yaffs data.
+ *
+ * This nand_ecclayout scatters/gathers to/from the old-yaffs layout with the
+ * page_status byte (at NAND spare offset 4) scattered/gathered from/to
+ * the 9th byte.
+ *
+ * Old-style on-NAND format: T0,T1,T2,T3,P,B,T4,T5,E0,E1,E2,T6,T7,E3,E4,E5
+ * We have/need packed_tags1 plus page_status: T0,T1,T2,T3,T4,T5,T6,T7,P
+ * where Tn are the tag bytes, En are MTD's ECC bytes, P is the page_status
+ * byte and B is the small-page bad-block indicator byte.
+ */
+static struct nand_ecclayout nand_oob_16 = {
+	.eccbytes = 6,
+	.eccpos = { 8, 9, 10, 13, 14, 15 },
+	.oobavail = 9,
+	.oobfree = { { 0, 4 }, { 6, 2 }, { 11, 2 }, { 4, 1 } }
+};
+#endif
+
+/* Write a chunk (page) of data to NAND.
+ *
+ * Caller always provides ExtendedTags data which are converted to a more
+ * compact (packed) form for storage in NAND.  A mini-ECC runs over the
+ * contents of the tags meta-data; used to valid the tags when read.
+ *
+ *  - Pack ExtendedTags to packed_tags1 form
+ *  - Compute mini-ECC for packed_tags1
+ *  - Write data and packed tags to NAND.
+ *
+ * Note: Due to the use of the packed_tags1 meta-data which does not include
+ * a full sequence number (as found in the larger packed_tags2 form) it is
+ * necessary for Yaffs to re-write a chunk/page (just once) to mark it as
+ * discarded and dirty.  This is not ideal: newer NAND parts are supposed
+ * to be written just once.  When Yaffs performs this operation, this
+ * function is called with a NULL data pointer -- calling MTD write_oob
+ * without data is valid usage (2.6.17).
+ *
+ * Any underlying MTD error results in YAFFS_FAIL.
+ * Returns YAFFS_OK or YAFFS_FAIL.
+ */
+int nandmtd1_write_chunk_tags(yaffs_dev_t *dev,
+	int nand_chunk, const __u8 *data, const yaffs_ext_tags *etags)
+{
+	struct mtd_info *mtd = yaffs_dev_to_mtd(dev);
+	int chunk_bytes = dev->data_bytes_per_chunk;
+	loff_t addr = ((loff_t)nand_chunk) * chunk_bytes;
+	struct mtd_oob_ops ops;
+	yaffs_packed_tags1 pt1;
+	int retval;
+
+	/* we assume that packed_tags1 and yaffs_tags_t are compatible */
+	compile_time_assertion(sizeof(yaffs_packed_tags1) == 12);
+	compile_time_assertion(sizeof(yaffs_tags_t) == 8);
+
+	yaffs_pack_tags1(&pt1, etags);
+	yaffs_calc_tags_ecc((yaffs_tags_t *)&pt1);
+
+	/* When deleting a chunk, the upper layer provides only skeletal
+	 * etags, one with is_deleted set.  However, we need to update the
+	 * tags, not erase them completely.  So we use the NAND write property
+	 * that only zeroed-bits stick and set tag bytes to all-ones and
+	 * zero just the (not) deleted bit.
+	 */
+#ifndef CONFIG_YAFFS_9BYTE_TAGS
+	if (etags->is_deleted) {
+		memset(&pt1, 0xff, 8);
+		/* clear delete status bit to indicate deleted */
+		pt1.deleted = 0;
+	}
+#else
+	((__u8 *)&pt1)[8] = 0xff;
+	if (etags->is_deleted) {
+		memset(&pt1, 0xff, 8);
+		/* zero page_status byte to indicate deleted */
+		((__u8 *)&pt1)[8] = 0;
+	}
+#endif
+
+	memset(&ops, 0, sizeof(ops));
+	ops.mode = MTD_OOB_AUTO;
+	ops.len = (data) ? chunk_bytes : 0;
+	ops.ooblen = YTAG1_SIZE;
+	ops.datbuf = (__u8 *)data;
+	ops.oobbuf = (__u8 *)&pt1;
+
+	retval = mtd->write_oob(mtd, addr, &ops);
+	if (retval) {
+		T(YAFFS_TRACE_MTD,
+			(TSTR("write_oob failed, chunk %d, mtd error %d"TENDSTR),
+			nand_chunk, retval));
+	}
+	return retval ? YAFFS_FAIL : YAFFS_OK;
+}
+
+/* Return with empty ExtendedTags but add ecc_result.
+ */
+static int rettags(yaffs_ext_tags *etags, int ecc_result, int retval)
+{
+	if (etags) {
+		memset(etags, 0, sizeof(*etags));
+		etags->ecc_result = ecc_result;
+	}
+	return retval;
+}
+
+/* Read a chunk (page) from NAND.
+ *
+ * Caller expects ExtendedTags data to be usable even on error; that is,
+ * all members except ecc_result and block_bad are zeroed.
+ *
+ *  - Check ECC results for data (if applicable)
+ *  - Check for blank/erased block (return empty ExtendedTags if blank)
+ *  - Check the packed_tags1 mini-ECC (correct if necessary/possible)
+ *  - Convert packed_tags1 to ExtendedTags
+ *  - Update ecc_result and block_bad members to refect state.
+ *
+ * Returns YAFFS_OK or YAFFS_FAIL.
+ */
+int nandmtd1_read_chunk_tags(yaffs_dev_t *dev,
+	int nand_chunk, __u8 *data, yaffs_ext_tags *etags)
+{
+	struct mtd_info *mtd = yaffs_dev_to_mtd(dev);
+	int chunk_bytes = dev->data_bytes_per_chunk;
+	loff_t addr = ((loff_t)nand_chunk) * chunk_bytes;
+	int eccres = YAFFS_ECC_RESULT_NO_ERROR;
+	struct mtd_oob_ops ops;
+	yaffs_packed_tags1 pt1;
+	int retval;
+	int deleted;
+
+	memset(&ops, 0, sizeof(ops));
+	ops.mode = MTD_OOB_AUTO;
+	ops.len = (data) ? chunk_bytes : 0;
+	ops.ooblen = YTAG1_SIZE;
+	ops.datbuf = data;
+	ops.oobbuf = (__u8 *)&pt1;
+
+#if (MTD_VERSION_CODE < MTD_VERSION(2, 6, 20))
+	/* In MTD 2.6.18 to 2.6.19 nand_base.c:nand_do_read_oob() has a bug;
+	 * help it out with ops.len = ops.ooblen when ops.datbuf == NULL.
+	 */
+	ops.len = (ops.datbuf) ? ops.len : ops.ooblen;
+#endif
+	/* Read page and oob using MTD.
+	 * Check status and determine ECC result.
+	 */
+	retval = mtd->read_oob(mtd, addr, &ops);
+	if (retval) {
+		T(YAFFS_TRACE_MTD,
+			(TSTR("read_oob failed, chunk %d, mtd error %d"TENDSTR),
+			nand_chunk, retval));
+	}
+
+	switch (retval) {
+	case 0:
+		/* no error */
+		break;
+
+	case -EUCLEAN:
+		/* MTD's ECC fixed the data */
+		eccres = YAFFS_ECC_RESULT_FIXED;
+		dev->n_ecc_fixed++;
+		break;
+
+	case -EBADMSG:
+		/* MTD's ECC could not fix the data */
+		dev->n_ecc_unfixed++;
+		/* fall into... */
+	default:
+		rettags(etags, YAFFS_ECC_RESULT_UNFIXED, 0);
+		etags->block_bad = (mtd->block_isbad)(mtd, addr);
+		return YAFFS_FAIL;
+	}
+
+	/* Check for a blank/erased chunk.
+	 */
+	if (yaffs_check_ff((__u8 *)&pt1, 8)) {
+		/* when blank, upper layers want ecc_result to be <= NO_ERROR */
+		return rettags(etags, YAFFS_ECC_RESULT_NO_ERROR, YAFFS_OK);
+	}
+
+#ifndef CONFIG_YAFFS_9BYTE_TAGS
+	/* Read deleted status (bit) then return it to it's non-deleted
+	 * state before performing tags mini-ECC check. pt1.deleted is
+	 * inverted.
+	 */
+	deleted = !pt1.deleted;
+	pt1.deleted = 1;
+#else
+	deleted = (yaffs_count_bits(((__u8 *)&pt1)[8]) < 7);
+#endif
+
+	/* Check the packed tags mini-ECC and correct if necessary/possible.
+	 */
+	retval = yaffs_check_tags_ecc((yaffs_tags_t *)&pt1);
+	switch (retval) {
+	case 0:
+		/* no tags error, use MTD result */
+		break;
+	case 1:
+		/* recovered tags-ECC error */
+		dev->n_tags_ecc_fixed++;
+		if (eccres == YAFFS_ECC_RESULT_NO_ERROR)
+			eccres = YAFFS_ECC_RESULT_FIXED;
+		break;
+	default:
+		/* unrecovered tags-ECC error */
+		dev->n_tags_ecc_unfixed++;
+		return rettags(etags, YAFFS_ECC_RESULT_UNFIXED, YAFFS_FAIL);
+	}
+
+	/* Unpack the tags to extended form and set ECC result.
+	 * [set should_be_ff just to keep yaffs_unpack_tags1 happy]
+	 */
+	pt1.should_be_ff = 0xFFFFFFFF;
+	yaffs_unpack_tags1(etags, &pt1);
+	etags->ecc_result = eccres;
+
+	/* Set deleted state */
+	etags->is_deleted = deleted;
+	return YAFFS_OK;
+}
+
+/* Mark a block bad.
+ *
+ * This is a persistant state.
+ * Use of this function should be rare.
+ *
+ * Returns YAFFS_OK or YAFFS_FAIL.
+ */
+int nandmtd1_mark_block_bad(struct yaffs_dev_s *dev, int block_no)
+{
+	struct mtd_info *mtd = yaffs_dev_to_mtd(dev);
+	int blocksize = dev->param.chunks_per_block * dev->data_bytes_per_chunk;
+	int retval;
+
+	T(YAFFS_TRACE_BAD_BLOCKS,(TSTR("marking block %d bad"TENDSTR), block_no));
+
+	retval = mtd->block_markbad(mtd, (loff_t)blocksize * block_no);
+	return (retval) ? YAFFS_FAIL : YAFFS_OK;
+}
+
+/* Check any MTD prerequists.
+ *
+ * Returns YAFFS_OK or YAFFS_FAIL.
+ */
+static int nandmtd1_test_prerequists(struct mtd_info *mtd)
+{
+	/* 2.6.18 has mtd->ecclayout->oobavail */
+	/* 2.6.21 has mtd->ecclayout->oobavail and mtd->oobavail */
+	int oobavail = mtd->ecclayout->oobavail;
+
+	if (oobavail < YTAG1_SIZE) {
+		T(YAFFS_TRACE_ERROR,
+			(TSTR("mtd device has only %d bytes for tags, need %d"TENDSTR),
+			oobavail, YTAG1_SIZE));
+		return YAFFS_FAIL;
+	}
+	return YAFFS_OK;
+}
+
+/* Query for the current state of a specific block.
+ *
+ * Examine the tags of the first chunk of the block and return the state:
+ *  - YAFFS_BLOCK_STATE_DEAD, the block is marked bad
+ *  - YAFFS_BLOCK_STATE_NEEDS_SCANNING, the block is in use
+ *  - YAFFS_BLOCK_STATE_EMPTY, the block is clean
+ *
+ * Always returns YAFFS_OK.
+ */
+int nandmtd1_query_block(struct yaffs_dev_s *dev, int block_no,
+	yaffs_block_state_t *state_ptr, __u32 *seq_ptr)
+{
+	struct mtd_info *mtd = yaffs_dev_to_mtd(dev);
+	int chunk_num = block_no * dev->param.chunks_per_block;
+	loff_t addr = (loff_t)chunk_num * dev->data_bytes_per_chunk;
+	yaffs_ext_tags etags;
+	int state = YAFFS_BLOCK_STATE_DEAD;
+	int seqnum = 0;
+	int retval;
+
+	/* We don't yet have a good place to test for MTD config prerequists.
+	 * Do it here as we are called during the initial scan.
+	 */
+	if (nandmtd1_test_prerequists(mtd) != YAFFS_OK)
+		return YAFFS_FAIL;
+
+	retval = nandmtd1_read_chunk_tags(dev, chunk_num, NULL, &etags);
+	etags.block_bad = (mtd->block_isbad)(mtd, addr);
+	if (etags.block_bad) {
+		T(YAFFS_TRACE_BAD_BLOCKS,
+			(TSTR("block %d is marked bad"TENDSTR), block_no));
+		state = YAFFS_BLOCK_STATE_DEAD;
+	} else if (etags.ecc_result != YAFFS_ECC_RESULT_NO_ERROR) {
+		/* bad tags, need to look more closely */
+		state = YAFFS_BLOCK_STATE_NEEDS_SCANNING;
+	} else if (etags.chunk_used) {
+		state = YAFFS_BLOCK_STATE_NEEDS_SCANNING;
+		seqnum = etags.seq_number;
+	} else {
+		state = YAFFS_BLOCK_STATE_EMPTY;
+	}
+
+	*state_ptr = state;
+	*seq_ptr = seqnum;
+
+	/* query always succeeds */
+	return YAFFS_OK;
+}
+
+#endif /*MTD_VERSION*/
diff --git a/drivers/staging/yaffs2/yaffs_mtdif1.h b/drivers/staging/yaffs2/yaffs_mtdif1.h
new file mode 100644
index 0000000..01a8ec4
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_mtdif1.h
@@ -0,0 +1,28 @@
+/*
+ * YAFFS: Yet another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_MTDIF1_H__
+#define __YAFFS_MTDIF1_H__
+
+int nandmtd1_write_chunk_tags(yaffs_dev_t *dev, int nand_chunk,
+	const __u8 *data, const yaffs_ext_tags *tags);
+
+int nandmtd1_read_chunk_tags(yaffs_dev_t *dev, int nand_chunk,
+	__u8 *data, yaffs_ext_tags *tags);
+
+int nandmtd1_mark_block_bad(struct yaffs_dev_s *dev, int block_no);
+
+int nandmtd1_query_block(struct yaffs_dev_s *dev, int block_no,
+	yaffs_block_state_t *state, __u32 *seq_number);
+
+#endif
-- 
1.7.3.2.146.gca209

[PATCH 15/29] Staging: yaffs2: yaffs_mtdif2: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_mtdif2.c |  256 +++++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_mtdif2.h |   29 ++++
 2 files changed, 285 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_mtdif2.c
 create mode 100644 drivers/staging/yaffs2/yaffs_mtdif2.h

diff --git a/drivers/staging/yaffs2/yaffs_mtdif2.c b/drivers/staging/yaffs2/yaffs_mtdif2.c
new file mode 100644
index 0000000..1c60a44
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_mtdif2.c
@@ -0,0 +1,256 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/* mtd interface for YAFFS2 */
+
+#include "yportenv.h"
+#include "yaffs_trace.h"
+
+#include "yaffs_mtdif2.h"
+
+#include "linux/mtd/mtd.h"
+#include "linux/types.h"
+#include "linux/time.h"
+
+#include "yaffs_packedtags2.h"
+
+#include "yaffs_linux.h"
+
+/* NB For use with inband tags....
+ * We assume that the data buffer is of size total_bytes_per_chunk so that we can also
+ * use it to load the tags.
+ */
+int nandmtd2_write_chunk_tags(yaffs_dev_t *dev, int nand_chunk,
+				      const __u8 *data,
+				      const yaffs_ext_tags *tags)
+{
+	struct mtd_info *mtd = yaffs_dev_to_mtd(dev);
+#if (MTD_VERSION_CODE > MTD_VERSION(2, 6, 17))
+	struct mtd_oob_ops ops;
+#else
+	size_t dummy;
+#endif
+	int retval = 0;
+
+	loff_t addr;
+
+	yaffs_packed_tags2 pt;
+
+	int packed_tags_size = dev->param.no_tags_ecc ? sizeof(pt.t) : sizeof(pt);
+	void * packed_tags_ptr = dev->param.no_tags_ecc ? (void *) &pt.t : (void *)&pt;
+
+	T(YAFFS_TRACE_MTD,
+	  (TSTR
+	   ("nandmtd2_write_chunk_tags chunk %d data %p tags %p"
+	    TENDSTR), nand_chunk, data, tags));
+
+
+	addr  = ((loff_t) nand_chunk) * dev->param.total_bytes_per_chunk;
+
+	/* For yaffs2 writing there must be both data and tags.
+	 * If we're using inband tags, then the tags are stuffed into
+	 * the end of the data buffer.
+	 */
+	if (!data || !tags)
+		BUG();
+	else if (dev->param.inband_tags) {
+		yaffs_packed_tags2_tags_only *pt2tp;
+		pt2tp = (yaffs_packed_tags2_tags_only *)(data + dev->data_bytes_per_chunk);
+		yaffs_pack_tags2_tags_only(pt2tp, tags);
+	} else
+		yaffs_pack_tags2(&pt, tags, !dev->param.no_tags_ecc);
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+	ops.mode = MTD_OOB_AUTO;
+	ops.ooblen = (dev->param.inband_tags) ? 0 : packed_tags_size;
+	ops.len = dev->param.total_bytes_per_chunk;
+	ops.ooboffs = 0;
+	ops.datbuf = (__u8 *)data;
+	ops.oobbuf = (dev->param.inband_tags) ? NULL : packed_tags_ptr;
+	retval = mtd->write_oob(mtd, addr, &ops);
+
+#else
+	if (!dev->param.inband_tags) {
+		retval =
+		    mtd->write_ecc(mtd, addr, dev->data_bytes_per_chunk,
+				   &dummy, data, (__u8 *) packed_tags_ptr, NULL);
+	} else {
+		retval =
+		    mtd->write(mtd, addr, dev->param.total_bytes_per_chunk, &dummy,
+			       data);
+	}
+#endif
+
+	if (retval == 0)
+		return YAFFS_OK;
+	else
+		return YAFFS_FAIL;
+}
+
+int nandmtd2_read_chunk_tags(yaffs_dev_t *dev, int nand_chunk,
+				       __u8 *data, yaffs_ext_tags *tags)
+{
+	struct mtd_info *mtd = yaffs_dev_to_mtd(dev);
+#if (MTD_VERSION_CODE > MTD_VERSION(2, 6, 17))
+	struct mtd_oob_ops ops;
+#endif
+	size_t dummy;
+	int retval = 0;
+	int local_data = 0;
+
+	loff_t addr = ((loff_t) nand_chunk) * dev->param.total_bytes_per_chunk;
+
+	yaffs_packed_tags2 pt;
+
+	int packed_tags_size = dev->param.no_tags_ecc ? sizeof(pt.t) : sizeof(pt);
+	void * packed_tags_ptr = dev->param.no_tags_ecc ? (void *) &pt.t: (void *)&pt;
+
+	T(YAFFS_TRACE_MTD,
+	  (TSTR
+	   ("nandmtd2_read_chunk_tags chunk %d data %p tags %p"
+	    TENDSTR), nand_chunk, data, tags));
+
+	if (dev->param.inband_tags) {
+
+		if (!data) {
+			local_data = 1;
+			data = yaffs_get_temp_buffer(dev, __LINE__);
+		}
+
+
+	}
+
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+	if (dev->param.inband_tags || (data && !tags))
+		retval = mtd->read(mtd, addr, dev->param.total_bytes_per_chunk,
+				&dummy, data);
+	else if (tags) {
+		ops.mode = MTD_OOB_AUTO;
+		ops.ooblen = packed_tags_size;
+		ops.len = data ? dev->data_bytes_per_chunk : packed_tags_size;
+		ops.ooboffs = 0;
+		ops.datbuf = data;
+		ops.oobbuf = yaffs_dev_to_lc(dev)->spare_buffer;
+		retval = mtd->read_oob(mtd, addr, &ops);
+	}
+#else
+	if (!dev->param.inband_tags && data && tags) {
+
+		retval = mtd->read_ecc(mtd, addr, dev->data_bytes_per_chunk,
+					  &dummy, data, dev->spare_buffer,
+					  NULL);
+	} else {
+		if (data)
+			retval =
+			    mtd->read(mtd, addr, dev->data_bytes_per_chunk, &dummy,
+				      data);
+		if (!dev->param.inband_tags && tags)
+			retval =
+			    mtd->read_oob(mtd, addr, mtd->oobsize, &dummy,
+					  dev->spare_buffer);
+	}
+#endif
+
+
+	if (dev->param.inband_tags) {
+		if (tags) {
+			yaffs_packed_tags2_tags_only *pt2tp;
+			pt2tp = (yaffs_packed_tags2_tags_only *)&data[dev->data_bytes_per_chunk];
+			yaffs_unpack_tags2_tags_only(tags, pt2tp);
+		}
+	} else {
+		if (tags) {
+			memcpy(packed_tags_ptr, yaffs_dev_to_lc(dev)->spare_buffer, packed_tags_size);
+			yaffs_unpack_tags2(tags, &pt, !dev->param.no_tags_ecc);
+		}
+	}
+
+	if (local_data)
+		yaffs_release_temp_buffer(dev, data, __LINE__);
+
+	if (tags && retval == -EBADMSG && tags->ecc_result == YAFFS_ECC_RESULT_NO_ERROR) {
+		tags->ecc_result = YAFFS_ECC_RESULT_UNFIXED;
+		dev->n_ecc_unfixed++;
+	}
+	if(tags && retval == -EUCLEAN && tags->ecc_result == YAFFS_ECC_RESULT_NO_ERROR) {
+		tags->ecc_result = YAFFS_ECC_RESULT_FIXED;
+		dev->n_ecc_fixed++;
+	}
+	if (retval == 0)
+		return YAFFS_OK;
+	else
+		return YAFFS_FAIL;
+}
+
+int nandmtd2_mark_block_bad(struct yaffs_dev_s *dev, int block_no)
+{
+	struct mtd_info *mtd = yaffs_dev_to_mtd(dev);
+	int retval;
+	T(YAFFS_TRACE_MTD,
+	  (TSTR("nandmtd2_mark_block_bad %d" TENDSTR), block_no));
+
+	retval =
+	    mtd->block_markbad(mtd,
+			       block_no * dev->param.chunks_per_block *
+			       dev->param.total_bytes_per_chunk);
+
+	if (retval == 0)
+		return YAFFS_OK;
+	else
+		return YAFFS_FAIL;
+
+}
+
+int nandmtd2_query_block(struct yaffs_dev_s *dev, int block_no,
+			    yaffs_block_state_t *state, __u32 *seq_number)
+{
+	struct mtd_info *mtd = yaffs_dev_to_mtd(dev);
+	int retval;
+
+	T(YAFFS_TRACE_MTD,
+	  (TSTR("nandmtd2_query_block %d" TENDSTR), block_no));
+	retval =
+	    mtd->block_isbad(mtd,
+			     block_no * dev->param.chunks_per_block *
+			     dev->param.total_bytes_per_chunk);
+
+	if (retval) {
+		T(YAFFS_TRACE_MTD, (TSTR("block is bad" TENDSTR)));
+
+		*state = YAFFS_BLOCK_STATE_DEAD;
+		*seq_number = 0;
+	} else {
+		yaffs_ext_tags t;
+		nandmtd2_read_chunk_tags(dev, block_no *
+						   dev->param.chunks_per_block, NULL,
+						   &t);
+
+		if (t.chunk_used) {
+			*seq_number = t.seq_number;
+			*state = YAFFS_BLOCK_STATE_NEEDS_SCANNING;
+		} else {
+			*seq_number = 0;
+			*state = YAFFS_BLOCK_STATE_EMPTY;
+		}
+	}
+	T(YAFFS_TRACE_MTD,
+	  (TSTR("block is bad seq %d state %d" TENDSTR), *seq_number,
+	   *state));
+
+	if (retval == 0)
+		return YAFFS_OK;
+	else
+		return YAFFS_FAIL;
+}
+
diff --git a/drivers/staging/yaffs2/yaffs_mtdif2.h b/drivers/staging/yaffs2/yaffs_mtdif2.h
new file mode 100644
index 0000000..b33b84d
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_mtdif2.h
@@ -0,0 +1,29 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_MTDIF2_H__
+#define __YAFFS_MTDIF2_H__
+
+#include "yaffs_guts.h"
+int nandmtd2_write_chunk_tags(yaffs_dev_t *dev, int nand_chunk,
+				const __u8 *data,
+				const yaffs_ext_tags *tags);
+int nandmtd2_read_chunk_tags(yaffs_dev_t *dev, int nand_chunk,
+				__u8 *data, yaffs_ext_tags *tags);
+int nandmtd2_mark_block_bad(struct yaffs_dev_s *dev, int block_no);
+int nandmtd2_query_block(struct yaffs_dev_s *dev, int block_no,
+			yaffs_block_state_t *state, __u32 *seq_number);
+
+#endif
-- 
1.7.3.2.146.gca209

Re: [PATCH 15/29] Staging: yaffs2: yaffs_mtdif2: Add files

[Jesper Juhl]

On Mon, 1 Nov 2010, Tracey Dent wrote:

> Adding files to yaffs2 directory.
> 
> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> ---
>  drivers/staging/yaffs2/yaffs_mtdif2.c |  256 +++++++++++++++++++++++++++++++++
>  drivers/staging/yaffs2/yaffs_mtdif2.h |   29 ++++
>  2 files changed, 285 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/yaffs2/yaffs_mtdif2.c
>  create mode 100644 drivers/staging/yaffs2/yaffs_mtdif2.h
> 
> diff --git a/drivers/staging/yaffs2/yaffs_mtdif2.c b/drivers/staging/yaffs2/yaffs_mtdif2.c
> new file mode 100644
> index 0000000..1c60a44
> --- /dev/null
> +++ b/drivers/staging/yaffs2/yaffs_mtdif2.c
...
> +#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
> +	ops.mode = MTD_OOB_AUTO;
> +	ops.ooblen = (dev->param.inband_tags) ? 0 : packed_tags_size;
> +	ops.len = dev->param.total_bytes_per_chunk;
> +	ops.ooboffs = 0;
> +	ops.datbuf = (__u8 *)data;
> +	ops.oobbuf = (dev->param.inband_tags) ? NULL : packed_tags_ptr;
> +	retval = mtd->write_oob(mtd, addr, &ops);
> +
> +#else
...
> +#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
> +	if (dev->param.inband_tags || (data && !tags))
> +		retval = mtd->read(mtd, addr, dev->param.total_bytes_per_chunk,
> +				&dummy, data);
> +	else if (tags) {
> +		ops.mode = MTD_OOB_AUTO;
> +		ops.ooblen = packed_tags_size;
> +		ops.len = data ? dev->data_bytes_per_chunk : packed_tags_size;
> +		ops.ooboffs = 0;
> +		ops.datbuf = data;
> +		ops.oobbuf = yaffs_dev_to_lc(dev)->spare_buffer;
> +		retval = mtd->read_oob(mtd, addr, &ops);
> +	}
> +#else
...

If/when this code gets merged it will definitely be into a kernel with a 
version greater than 2.6.17, so I believe you should just get rid of the 
#ifdef and the code in the #else parts.

-- 
Jesper Juhl <jj@chaosbits.net>             http://www.chaosbits.net/
Plain text mails only, please      http://www.expita.com/nomime.html
Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html

[PATCH 16/29] Staging: yaffs2: yaffs_nameval: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_nameval.c |  197 ++++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_nameval.h |   26 ++++
 2 files changed, 223 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_nameval.c
 create mode 100644 drivers/staging/yaffs2/yaffs_nameval.h

diff --git a/drivers/staging/yaffs2/yaffs_nameval.c b/drivers/staging/yaffs2/yaffs_nameval.c
new file mode 100644
index 0000000..a4ed297
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_nameval.c
@@ -0,0 +1,197 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/*
+ * This simple implementation of a name-value store assumes a small number of values and fits
+ * into a small finite buffer.
+ *
+ * Each attribute is stored as a record:
+ *  sizeof(int) bytes   record size.
+ *  strnlen+1 bytes name null terminated.
+ *  nbytes    value.
+ *  ----------
+ *  total size  stored in record size 
+ *
+ * This code has not been tested with unicode yet.
+ */
+
+
+#include "yaffs_nameval.h"
+
+#include "yportenv.h"
+ 
+static int nval_find(const char *xb, int xb_size, const YCHAR *name,
+		int *exist_size)
+{
+	int pos=0;
+	int size;
+
+	memcpy(&size,xb,sizeof(int));
+	while(size > 0 && (size < xb_size) && (pos + size < xb_size)){
+		if(yaffs_strncmp((YCHAR *)(xb+pos+sizeof(int)),name,size) == 0){
+			if(exist_size)
+				*exist_size = size;
+			return pos;
+		}
+		pos += size;
+		if(pos < xb_size -sizeof(int))
+			memcpy(&size,xb + pos,sizeof(int));
+		else
+			size = 0;
+	}
+	if(exist_size)
+		*exist_size = 0;
+	return -1;
+}
+
+static int nval_used(const char *xb, int xb_size)
+{
+	int pos=0;
+	int size;
+
+	memcpy(&size,xb + pos,sizeof(int));
+	while(size > 0 && (size < xb_size) && (pos + size < xb_size)){
+		pos += size;
+		if(pos < xb_size -sizeof(int))
+			memcpy(&size,xb + pos,sizeof(int));
+		else
+			size = 0;
+	}
+	return pos;
+}
+
+int nval_del(char *xb, int xb_size, const YCHAR *name)
+{
+	int pos  = nval_find(xb, xb_size, name, NULL);
+	int size;
+	
+	if(pos >= 0 && pos < xb_size){
+		/* Find size, shift rest over this record, then zero out the rest of buffer */
+		memcpy(&size,xb+pos,sizeof(int));
+		memcpy(xb + pos, xb + pos + size, xb_size - (pos + size));
+		memset(xb + (xb_size - size),0,size);
+		return 0;
+	} else
+		return -ENODATA;
+}
+
+int nval_set(char *xb, int xb_size, const YCHAR *name, const char *buf, int bsize, int flags)
+{
+	int pos;
+	int namelen = yaffs_strnlen(name,xb_size);
+	int reclen;
+	int size_exist = 0;
+	int space;
+	int start;
+
+	pos = nval_find(xb,xb_size,name, &size_exist);
+
+	if(flags & XATTR_CREATE && pos >= 0)
+		return -EEXIST;
+	if(flags & XATTR_REPLACE && pos < 0)
+		return -ENODATA;
+
+	start = nval_used(xb,xb_size);
+	space = xb_size - start + size_exist;
+
+	reclen = (sizeof(int) + namelen + 1 + bsize);
+
+	if(reclen > space)
+		return -ENOSPC;
+
+	if(pos >= 0){
+		nval_del(xb,xb_size,name);
+		start = nval_used(xb, xb_size);
+	}
+
+	pos = start;
+
+	memcpy(xb + pos,&reclen,sizeof(int));
+	pos +=sizeof(int);
+	yaffs_strncpy((YCHAR *)(xb + pos), name, reclen);
+	pos+= (namelen+1);
+	memcpy(xb + pos,buf,bsize);
+	return 0;
+}
+
+int nval_get(const char *xb, int xb_size, const YCHAR *name, char *buf, int bsize)
+{
+	int pos = nval_find(xb,xb_size,name,NULL);
+	int size;
+	
+	if(pos >= 0 && pos< xb_size){
+		
+		memcpy(&size,xb +pos,sizeof(int));
+		pos+=sizeof(int); /* advance past record length */
+		size -= sizeof(int);
+
+		/* Advance over name string */
+		while(xb[pos] && size > 0 && pos < xb_size){
+			pos++;
+			size--;
+		}
+		/*Advance over NUL */
+		pos++;
+		size--;
+
+		if(size <= bsize){
+			memcpy(buf,xb + pos,size);
+			return size;
+		}
+		
+	}
+	if(pos >= 0)
+		return -ERANGE;
+	else
+		return -ENODATA;
+}
+
+int nval_list(const char *xb, int xb_size, char *buf, int bsize)
+{
+	int pos = 0;
+	int size;
+	int name_len;
+	int ncopied = 0;
+	int filled = 0;
+
+	memcpy(&size,xb + pos,sizeof(int));
+	while(size > sizeof(int) && size <= xb_size && (pos + size) < xb_size && !filled){
+		pos+= sizeof(int);
+		size-=sizeof(int);
+		name_len = yaffs_strnlen((YCHAR *)(xb + pos), size);
+		if(ncopied + name_len + 1 < bsize){
+			memcpy(buf,xb+pos,name_len * sizeof(YCHAR));
+			buf+= name_len;
+			*buf = '\0';
+			buf++;
+			if(sizeof(YCHAR) > 1){
+				*buf = '\0';
+				buf++;
+			}
+			ncopied += (name_len+1);
+		} else
+			filled = 1;
+		pos+=size;
+		if(pos < xb_size -sizeof(int))
+			memcpy(&size,xb + pos,sizeof(int));
+		else
+			size = 0;
+	}
+	return ncopied;
+}
+
+
+int nval_hasvalues(const char *xb, int xb_size)
+{
+	return nval_used(xb, xb_size) > 0;
+}
diff --git a/drivers/staging/yaffs2/yaffs_nameval.h b/drivers/staging/yaffs2/yaffs_nameval.h
new file mode 100644
index 0000000..bd80859
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_nameval.h
@@ -0,0 +1,26 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __NAMEVAL_H__
+#define __NAMEVAL_H__
+
+#include "yportenv.h"
+
+int nval_del(char *xb, int xb_size, const YCHAR *name);
+int nval_set(char *xb, int xb_size, const YCHAR *name, const char *buf, int bsize, int flags);
+int nval_get(const char *xb, int xb_size, const YCHAR *name, char *buf, int bsize);
+int nval_list(const char *xb, int xb_size, char *buf, int bsize);
+int nval_hasvalues(const char *xb, int xb_size);
+#endif
-- 
1.7.3.2.146.gca209

[PATCH 17/29] Staging: yaffs2: yaffs_nand: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_nand.c |  140 +++++++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_nand.h |   44 +++++++++++
 2 files changed, 184 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_nand.c
 create mode 100644 drivers/staging/yaffs2/yaffs_nand.h

diff --git a/drivers/staging/yaffs2/yaffs_nand.c b/drivers/staging/yaffs2/yaffs_nand.c
new file mode 100644
index 0000000..d721fa6
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_nand.c
@@ -0,0 +1,140 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_nand.h"
+#include "yaffs_tagscompat.h"
+#include "yaffs_tagsvalidity.h"
+
+#include "yaffs_getblockinfo.h"
+
+int yaffs_rd_chunk_tags_nand(yaffs_dev_t *dev, int nand_chunk,
+					   __u8 *buffer,
+					   yaffs_ext_tags *tags)
+{
+	int result;
+	yaffs_ext_tags local_tags;
+
+	int realigned_chunk = nand_chunk - dev->chunk_offset;
+
+	dev->n_page_reads++;
+
+	/* If there are no tags provided, use local tags to get prioritised gc working */
+	if (!tags)
+		tags = &local_tags;
+
+	if (dev->param.read_chunk_tags_fn)
+		result = dev->param.read_chunk_tags_fn(dev, realigned_chunk, buffer,
+						      tags);
+	else
+		result = yaffs_tags_compat_rd(dev,
+									realigned_chunk,
+									buffer,
+									tags);
+	if (tags &&
+	   tags->ecc_result > YAFFS_ECC_RESULT_NO_ERROR) {
+
+		yaffs_block_info_t *bi;
+		bi = yaffs_get_block_info(dev, nand_chunk/dev->param.chunks_per_block);
+		yaffs_handle_chunk_error(dev, bi);
+	}
+
+	return result;
+}
+
+int yaffs_wr_chunk_tags_nand(yaffs_dev_t *dev,
+						   int nand_chunk,
+						   const __u8 *buffer,
+						   yaffs_ext_tags *tags)
+{
+
+	dev->n_page_writes++;
+
+	nand_chunk -= dev->chunk_offset;
+
+
+	if (tags) {
+		tags->seq_number = dev->seq_number;
+		tags->chunk_used = 1;
+		if (!yaffs_validate_tags(tags)) {
+			T(YAFFS_TRACE_ERROR,
+			  (TSTR("Writing uninitialised tags" TENDSTR)));
+			YBUG();
+		}
+		T(YAFFS_TRACE_WRITE,
+		  (TSTR("Writing chunk %d tags %d %d" TENDSTR), nand_chunk,
+		   tags->obj_id, tags->chunk_id));
+	} else {
+		T(YAFFS_TRACE_ERROR, (TSTR("Writing with no tags" TENDSTR)));
+		YBUG();
+	}
+
+	if (dev->param.write_chunk_tags_fn)
+		return dev->param.write_chunk_tags_fn(dev, nand_chunk, buffer,
+						     tags);
+	else
+		return yaffs_tags_compat_wr(dev,
+								       nand_chunk,
+								       buffer,
+								       tags);
+}
+
+int yaffs_mark_bad(yaffs_dev_t *dev, int block_no)
+{
+	block_no -= dev->block_offset;
+
+
+	if (dev->param.bad_block_fn)
+		return dev->param.bad_block_fn(dev, block_no);
+	else
+		return yaffs_tags_compat_mark_bad(dev, block_no);
+}
+
+int yaffs_query_init_block_state(yaffs_dev_t *dev,
+						 int block_no,
+						 yaffs_block_state_t *state,
+						 __u32 *seq_number)
+{
+	block_no -= dev->block_offset;
+
+	if (dev->param.query_block_fn)
+		return dev->param.query_block_fn(dev, block_no, state, seq_number);
+	else
+		return yaffs_tags_compat_query_block(dev, block_no,
+							     state,
+							     seq_number);
+}
+
+
+int yaffs_erase_block(struct yaffs_dev_s *dev,
+				  int flash_block)
+{
+	int result;
+
+	flash_block -= dev->block_offset;
+
+	dev->n_erasures++;
+
+	result = dev->param.erase_fn(dev, flash_block);
+
+	return result;
+}
+
+int yaffs_init_nand(struct yaffs_dev_s *dev)
+{
+	if(dev->param.initialise_flash_fn)
+		return dev->param.initialise_flash_fn(dev);
+	return YAFFS_OK;
+}
+
+
+
diff --git a/drivers/staging/yaffs2/yaffs_nand.h b/drivers/staging/yaffs2/yaffs_nand.h
new file mode 100644
index 0000000..24cd147
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_nand.h
@@ -0,0 +1,44 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_NAND_H__
+#define __YAFFS_NAND_H__
+#include "yaffs_guts.h"
+
+
+
+int yaffs_rd_chunk_tags_nand(yaffs_dev_t *dev, int nand_chunk,
+					__u8 *buffer,
+					yaffs_ext_tags *tags);
+
+int yaffs_wr_chunk_tags_nand(yaffs_dev_t *dev,
+						int nand_chunk,
+						const __u8 *buffer,
+						yaffs_ext_tags *tags);
+
+int yaffs_mark_bad(yaffs_dev_t *dev, int block_no);
+
+int yaffs_query_init_block_state(yaffs_dev_t *dev,
+						int block_no,
+						yaffs_block_state_t *state,
+						unsigned *seq_number);
+
+int yaffs_erase_block(struct yaffs_dev_s *dev,
+				  int flash_block);
+
+int yaffs_init_nand(struct yaffs_dev_s *dev);
+
+#endif
+
-- 
1.7.3.2.146.gca209

[PATCH 18/29] Staging: yaffs2: yaffs_packedtags1: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_packedtags1.c |   50 ++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_packedtags1.h |   37 ++++++++++++++++++++
 2 files changed, 87 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_packedtags1.c
 create mode 100644 drivers/staging/yaffs2/yaffs_packedtags1.h

diff --git a/drivers/staging/yaffs2/yaffs_packedtags1.c b/drivers/staging/yaffs2/yaffs_packedtags1.c
new file mode 100644
index 0000000..2ce873f
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_packedtags1.c
@@ -0,0 +1,50 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_packedtags1.h"
+#include "yportenv.h"
+
+void yaffs_pack_tags1(yaffs_packed_tags1 *pt, const yaffs_ext_tags *t)
+{
+	pt->chunk_id = t->chunk_id;
+	pt->serial_number = t->serial_number;
+	pt->n_bytes = t->n_bytes;
+	pt->obj_id = t->obj_id;
+	pt->ecc = 0;
+	pt->deleted = (t->is_deleted) ? 0 : 1;
+	pt->unused_stuff = 0;
+	pt->should_be_ff = 0xFFFFFFFF;
+
+}
+
+void yaffs_unpack_tags1(yaffs_ext_tags *t, const yaffs_packed_tags1 *pt)
+{
+	static const __u8 all_ff[] =
+	    { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+0xff };
+
+	if (memcmp(all_ff, pt, sizeof(yaffs_packed_tags1))) {
+		t->block_bad = 0;
+		if (pt->should_be_ff != 0xFFFFFFFF)
+			t->block_bad = 1;
+		t->chunk_used = 1;
+		t->obj_id = pt->obj_id;
+		t->chunk_id = pt->chunk_id;
+		t->n_bytes = pt->n_bytes;
+		t->ecc_result = YAFFS_ECC_RESULT_NO_ERROR;
+		t->is_deleted = (pt->deleted) ? 0 : 1;
+		t->serial_number = pt->serial_number;
+	} else {
+		memset(t, 0, sizeof(yaffs_ext_tags));
+	}
+}
diff --git a/drivers/staging/yaffs2/yaffs_packedtags1.h b/drivers/staging/yaffs2/yaffs_packedtags1.h
new file mode 100644
index 0000000..50f32e8
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_packedtags1.h
@@ -0,0 +1,37 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+/* This is used to pack YAFFS1 tags, not YAFFS2 tags. */
+
+#ifndef __YAFFS_PACKEDTAGS1_H__
+#define __YAFFS_PACKEDTAGS1_H__
+
+#include "yaffs_guts.h"
+
+typedef struct {
+	unsigned chunk_id:20;
+	unsigned serial_number:2;
+	unsigned n_bytes:10;
+	unsigned obj_id:18;
+	unsigned ecc:12;
+	unsigned deleted:1;
+	unsigned unused_stuff:1;
+	unsigned should_be_ff;
+
+} yaffs_packed_tags1;
+
+void yaffs_pack_tags1(yaffs_packed_tags1 *pt, const yaffs_ext_tags *t);
+void yaffs_unpack_tags1(yaffs_ext_tags *t, const yaffs_packed_tags1 *pt);
+#endif
-- 
1.7.3.2.146.gca209

[PATCH 19/29] Staging: yaffs2: yaffs_packedtags2: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_packedtags2.c |  198 ++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_packedtags2.h |   43 ++++++
 2 files changed, 241 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_packedtags2.c
 create mode 100644 drivers/staging/yaffs2/yaffs_packedtags2.h

diff --git a/drivers/staging/yaffs2/yaffs_packedtags2.c b/drivers/staging/yaffs2/yaffs_packedtags2.c
new file mode 100644
index 0000000..4873f78
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_packedtags2.c
@@ -0,0 +1,198 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_packedtags2.h"
+#include "yportenv.h"
+#include "yaffs_trace.h"
+#include "yaffs_tagsvalidity.h"
+
+/* This code packs a set of extended tags into a binary structure for
+ * NAND storage
+ */
+
+/* Some of the information is "extra" struff which can be packed in to
+ * speed scanning
+ * This is defined by having the EXTRA_HEADER_INFO_FLAG set.
+ */
+
+/* Extra flags applied to chunk_id */
+
+#define EXTRA_HEADER_INFO_FLAG	0x80000000
+#define EXTRA_SHRINK_FLAG	0x40000000
+#define EXTRA_SHADOWS_FLAG	0x20000000
+#define EXTRA_SPARE_FLAGS	0x10000000
+
+#define ALL_EXTRA_FLAGS		0xF0000000
+
+/* Also, the top 4 bits of the object Id are set to the object type. */
+#define EXTRA_OBJECT_TYPE_SHIFT (28)
+#define EXTRA_OBJECT_TYPE_MASK  ((0x0F) << EXTRA_OBJECT_TYPE_SHIFT)
+
+
+static void yaffs_dump_packed_tags2_tags_only(const yaffs_packed_tags2_tags_only *ptt)
+{
+	T(YAFFS_TRACE_MTD,
+	  (TSTR("packed tags obj %d chunk %d byte %d seq %d" TENDSTR),
+	   ptt->obj_id, ptt->chunk_id, ptt->n_bytes,
+	   ptt->seq_number));
+}
+static void yaffs_dump_packed_tags2(const yaffs_packed_tags2 *pt)
+{
+	yaffs_dump_packed_tags2_tags_only(&pt->t);
+}
+
+static void yaffs_dump_tags2(const yaffs_ext_tags *t)
+{
+	T(YAFFS_TRACE_MTD,
+	  (TSTR
+	   ("ext.tags eccres %d blkbad %d chused %d obj %d chunk%d byte %d del %d ser %d seq %d"
+	    TENDSTR), t->ecc_result, t->block_bad, t->chunk_used, t->obj_id,
+	   t->chunk_id, t->n_bytes, t->is_deleted, t->serial_number,
+	   t->seq_number));
+
+}
+
+void yaffs_pack_tags2_tags_only(yaffs_packed_tags2_tags_only *ptt,
+		const yaffs_ext_tags *t)
+{
+	ptt->chunk_id = t->chunk_id;
+	ptt->seq_number = t->seq_number;
+	ptt->n_bytes = t->n_bytes;
+	ptt->obj_id = t->obj_id;
+
+	if (t->chunk_id == 0 && t->extra_available) {
+		/* Store the extra header info instead */
+		/* We save the parent object in the chunk_id */
+		ptt->chunk_id = EXTRA_HEADER_INFO_FLAG
+			| t->extra_parent_id;
+		if (t->extra_is_shrink)
+			ptt->chunk_id |= EXTRA_SHRINK_FLAG;
+		if (t->extra_shadows)
+			ptt->chunk_id |= EXTRA_SHADOWS_FLAG;
+
+		ptt->obj_id &= ~EXTRA_OBJECT_TYPE_MASK;
+		ptt->obj_id |=
+		    (t->extra_obj_type << EXTRA_OBJECT_TYPE_SHIFT);
+
+		if (t->extra_obj_type == YAFFS_OBJECT_TYPE_HARDLINK)
+			ptt->n_bytes = t->extra_equiv_id;
+		else if (t->extra_obj_type == YAFFS_OBJECT_TYPE_FILE)
+			ptt->n_bytes = t->extra_length;
+		else
+			ptt->n_bytes = 0;
+	}
+
+	yaffs_dump_packed_tags2_tags_only(ptt);
+	yaffs_dump_tags2(t);
+}
+
+
+void yaffs_pack_tags2(yaffs_packed_tags2 *pt, const yaffs_ext_tags *t, int tags_ecc)
+{
+	yaffs_pack_tags2_tags_only(&pt->t, t);
+
+	if(tags_ecc)
+		yaffs_ecc_calc_other((unsigned char *)&pt->t,
+					sizeof(yaffs_packed_tags2_tags_only),
+					&pt->ecc);
+}
+
+
+void yaffs_unpack_tags2_tags_only(yaffs_ext_tags *t,
+		yaffs_packed_tags2_tags_only *ptt)
+{
+
+	memset(t, 0, sizeof(yaffs_ext_tags));
+
+	yaffs_init_tags(t);
+
+	if (ptt->seq_number != 0xFFFFFFFF) {
+		t->block_bad = 0;
+		t->chunk_used = 1;
+		t->obj_id = ptt->obj_id;
+		t->chunk_id = ptt->chunk_id;
+		t->n_bytes = ptt->n_bytes;
+		t->is_deleted = 0;
+		t->serial_number = 0;
+		t->seq_number = ptt->seq_number;
+
+		/* Do extra header info stuff */
+
+		if (ptt->chunk_id & EXTRA_HEADER_INFO_FLAG) {
+			t->chunk_id = 0;
+			t->n_bytes = 0;
+
+			t->extra_available = 1;
+			t->extra_parent_id =
+			    ptt->chunk_id & (~(ALL_EXTRA_FLAGS));
+			t->extra_is_shrink =
+			    (ptt->chunk_id & EXTRA_SHRINK_FLAG) ? 1 : 0;
+			t->extra_shadows =
+			    (ptt->chunk_id & EXTRA_SHADOWS_FLAG) ? 1 : 0;
+			t->extra_obj_type =
+			    ptt->obj_id >> EXTRA_OBJECT_TYPE_SHIFT;
+			t->obj_id &= ~EXTRA_OBJECT_TYPE_MASK;
+
+			if (t->extra_obj_type == YAFFS_OBJECT_TYPE_HARDLINK)
+				t->extra_equiv_id = ptt->n_bytes;
+			else
+				t->extra_length = ptt->n_bytes;
+		}
+	}
+
+	yaffs_dump_packed_tags2_tags_only(ptt);
+	yaffs_dump_tags2(t);
+
+}
+
+
+void yaffs_unpack_tags2(yaffs_ext_tags *t, yaffs_packed_tags2 *pt, int tags_ecc)
+{
+
+	yaffs_ecc_result ecc_result = YAFFS_ECC_RESULT_NO_ERROR;
+
+	if (pt->t.seq_number != 0xFFFFFFFF &&
+	    tags_ecc){
+		/* Chunk is in use and we need to do ECC */
+		
+		yaffs_ecc_other ecc;
+		int result;
+		yaffs_ecc_calc_other((unsigned char *)&pt->t,
+					sizeof(yaffs_packed_tags2_tags_only),
+					&ecc);
+		result = yaffs_ecc_correct_other((unsigned char *)&pt->t,
+						sizeof(yaffs_packed_tags2_tags_only),
+						&pt->ecc, &ecc);
+		switch (result) {
+			case 0:
+				ecc_result = YAFFS_ECC_RESULT_NO_ERROR;
+				break;
+			case 1:
+				ecc_result = YAFFS_ECC_RESULT_FIXED;
+				break;
+			case -1:
+				ecc_result = YAFFS_ECC_RESULT_UNFIXED;
+				break;
+			default:
+				ecc_result = YAFFS_ECC_RESULT_UNKNOWN;
+		}
+	}
+
+	yaffs_unpack_tags2_tags_only(t, &pt->t);
+
+	t->ecc_result = ecc_result;
+
+	yaffs_dump_packed_tags2(pt);
+	yaffs_dump_tags2(t);
+}
+
diff --git a/drivers/staging/yaffs2/yaffs_packedtags2.h b/drivers/staging/yaffs2/yaffs_packedtags2.h
new file mode 100644
index 0000000..fd7a239
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_packedtags2.h
@@ -0,0 +1,43 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+/* This is used to pack YAFFS2 tags, not YAFFS1tags. */
+
+#ifndef __YAFFS_PACKEDTAGS2_H__
+#define __YAFFS_PACKEDTAGS2_H__
+
+#include "yaffs_guts.h"
+#include "yaffs_ecc.h"
+
+typedef struct {
+	unsigned seq_number;
+	unsigned obj_id;
+	unsigned chunk_id;
+	unsigned n_bytes;
+} yaffs_packed_tags2_tags_only;
+
+typedef struct {
+	yaffs_packed_tags2_tags_only t;
+	yaffs_ecc_other ecc;
+} yaffs_packed_tags2;
+
+/* Full packed tags with ECC, used for oob tags */
+void yaffs_pack_tags2(yaffs_packed_tags2 *pt, const yaffs_ext_tags *t, int tags_ecc);
+void yaffs_unpack_tags2(yaffs_ext_tags *t, yaffs_packed_tags2 *pt, int tags_ecc);
+
+/* Only the tags part (no ECC for use with inband tags */
+void yaffs_pack_tags2_tags_only(yaffs_packed_tags2_tags_only *pt, const yaffs_ext_tags *t);
+void yaffs_unpack_tags2_tags_only(yaffs_ext_tags *t, yaffs_packed_tags2_tags_only *pt);
+#endif
-- 
1.7.3.2.146.gca209

[PATCH 20/29] Staging: yaffs2: yaffs_qsort.h: Add file

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_qsort.h |   34 ++++++++++++++++++++++++++++++++++
 1 files changed, 34 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_qsort.h

diff --git a/drivers/staging/yaffs2/yaffs_qsort.h b/drivers/staging/yaffs2/yaffs_qsort.h
new file mode 100644
index 0000000..4a4981b
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_qsort.h
@@ -0,0 +1,34 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+
+#ifndef __YAFFS_QSORT_H__
+#define __YAFFS_QSORT_H__
+
+#ifdef __KERNEL__
+#include <linux/sort.h>
+
+extern void yaffs_qsort(void *const base, size_t total_elems, size_t size,
+			int (*cmp)(const void *, const void *)){
+	sort(base, total_elems, size, cmp, NULL);
+}
+
+#else
+
+extern void yaffs_qsort(void *const base, size_t total_elems, size_t size,
+			int (*cmp)(const void *, const void *));
+
+#endif
+#endif
-- 
1.7.3.2.146.gca209

Re: [PATCH 20/29] Staging: yaffs2: yaffs_qsort.h: Add file

[Pekka Enberg]

On Mon, Nov 1, 2010 at 8:41 PM, Tracey Dent <tdent48227@gmail.com> wrote:
> Adding files to yaffs2 directory.
>
> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> ---
>  drivers/staging/yaffs2/yaffs_qsort.h |   34 ++++++++++++++++++++++++++++++++++
>  1 files changed, 34 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/yaffs2/yaffs_qsort.h
>
> diff --git a/drivers/staging/yaffs2/yaffs_qsort.h b/drivers/staging/yaffs2/yaffs_qsort.h
> new file mode 100644
> index 0000000..4a4981b
> --- /dev/null
> +++ b/drivers/staging/yaffs2/yaffs_qsort.h
> +#ifndef __YAFFS_QSORT_H__
> +#define __YAFFS_QSORT_H__
> +
> +#ifdef __KERNEL__
> +#include <linux/sort.h>
> +
> +extern void yaffs_qsort(void *const base, size_t total_elems, size_t size,
> +                       int (*cmp)(const void *, const void *)){
> +       sort(base, total_elems, size, cmp, NULL);
> +}
> +
> +#else
> +
> +extern void yaffs_qsort(void *const base, size_t total_elems, size_t size,
> +                       int (*cmp)(const void *, const void *));
> +
> +#endif
> +#endif

Kill this wrapper.
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[PATCH 21/29] Staging: yaffs2: yaffs_tagscompact: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_tagscompat.c |  539 +++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_tagscompat.h |   39 ++
 2 files changed, 578 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_tagscompat.c
 create mode 100644 drivers/staging/yaffs2/yaffs_tagscompat.h

diff --git a/drivers/staging/yaffs2/yaffs_tagscompat.c b/drivers/staging/yaffs2/yaffs_tagscompat.c
new file mode 100644
index 0000000..1e910f2
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_tagscompat.c
@@ -0,0 +1,539 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_guts.h"
+#include "yaffs_tagscompat.h"
+#include "yaffs_ecc.h"
+#include "yaffs_getblockinfo.h"
+#include "yaffs_trace.h"
+
+static void yaffs_handle_rd_data_error(yaffs_dev_t *dev, int nand_chunk);
+#ifdef NOTYET
+static void yaffs_check_written_block(yaffs_dev_t *dev, int nand_chunk);
+static void yaffs_handle_chunk_wr_ok(yaffs_dev_t *dev, int nand_chunk,
+				     const __u8 *data,
+				     const yaffs_spare *spare);
+static void yaffs_handle_chunk_update(yaffs_dev_t *dev, int nand_chunk,
+				    const yaffs_spare *spare);
+static void yaffs_handle_chunk_wr_error(yaffs_dev_t *dev, int nand_chunk);
+#endif
+
+static const char yaffs_count_bits_table[256] = {
+	0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4,
+	1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+	1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+	2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+	1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+	2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+	2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+	3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+	1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+	2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+	2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+	3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+	2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+	3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+	3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+	4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8
+};
+
+int yaffs_count_bits(__u8 x)
+{
+	int ret_val;
+	ret_val = yaffs_count_bits_table[x];
+	return ret_val;
+}
+
+/********** Tags ECC calculations  *********/
+
+void yaffs_calc_ecc(const __u8 *data, yaffs_spare *spare)
+{
+	yaffs_ecc_cacl(data, spare->ecc1);
+	yaffs_ecc_cacl(&data[256], spare->ecc2);
+}
+
+void yaffs_calc_tags_ecc(yaffs_tags_t *tags)
+{
+	/* Calculate an ecc */
+
+	unsigned char *b = ((yaffs_tags_union_t *) tags)->as_bytes;
+	unsigned i, j;
+	unsigned ecc = 0;
+	unsigned bit = 0;
+
+	tags->ecc = 0;
+
+	for (i = 0; i < 8; i++) {
+		for (j = 1; j & 0xff; j <<= 1) {
+			bit++;
+			if (b[i] & j)
+				ecc ^= bit;
+		}
+	}
+
+	tags->ecc = ecc;
+
+}
+
+int yaffs_check_tags_ecc(yaffs_tags_t *tags)
+{
+	unsigned ecc = tags->ecc;
+
+	yaffs_calc_tags_ecc(tags);
+
+	ecc ^= tags->ecc;
+
+	if (ecc && ecc <= 64) {
+		/* TODO: Handle the failure better. Retire? */
+		unsigned char *b = ((yaffs_tags_union_t *) tags)->as_bytes;
+
+		ecc--;
+
+		b[ecc / 8] ^= (1 << (ecc & 7));
+
+		/* Now recvalc the ecc */
+		yaffs_calc_tags_ecc(tags);
+
+		return 1;	/* recovered error */
+	} else if (ecc) {
+		/* Wierd ecc failure value */
+		/* TODO Need to do somethiong here */
+		return -1;	/* unrecovered error */
+	}
+
+	return 0;
+}
+
+/********** Tags **********/
+
+static void yaffs_load_tags_to_spare(yaffs_spare *spare_ptr,
+				yaffs_tags_t *tags_ptr)
+{
+	yaffs_tags_union_t *tu = (yaffs_tags_union_t *) tags_ptr;
+
+	yaffs_calc_tags_ecc(tags_ptr);
+
+	spare_ptr->tb0 = tu->as_bytes[0];
+	spare_ptr->tb1 = tu->as_bytes[1];
+	spare_ptr->tb2 = tu->as_bytes[2];
+	spare_ptr->tb3 = tu->as_bytes[3];
+	spare_ptr->tb4 = tu->as_bytes[4];
+	spare_ptr->tb5 = tu->as_bytes[5];
+	spare_ptr->tb6 = tu->as_bytes[6];
+	spare_ptr->tb7 = tu->as_bytes[7];
+}
+
+static void yaffs_get_tags_from_spare(yaffs_dev_t *dev, yaffs_spare *spare_ptr,
+				yaffs_tags_t *tags_ptr)
+{
+	yaffs_tags_union_t *tu = (yaffs_tags_union_t *) tags_ptr;
+	int result;
+
+	tu->as_bytes[0] = spare_ptr->tb0;
+	tu->as_bytes[1] = spare_ptr->tb1;
+	tu->as_bytes[2] = spare_ptr->tb2;
+	tu->as_bytes[3] = spare_ptr->tb3;
+	tu->as_bytes[4] = spare_ptr->tb4;
+	tu->as_bytes[5] = spare_ptr->tb5;
+	tu->as_bytes[6] = spare_ptr->tb6;
+	tu->as_bytes[7] = spare_ptr->tb7;
+
+	result = yaffs_check_tags_ecc(tags_ptr);
+	if (result > 0)
+		dev->n_tags_ecc_fixed++;
+	else if (result < 0)
+		dev->n_tags_ecc_unfixed++;
+}
+
+static void yaffs_spare_init(yaffs_spare *spare)
+{
+	memset(spare, 0xFF, sizeof(yaffs_spare));
+}
+
+static int yaffs_wr_nand(struct yaffs_dev_s *dev,
+				int nand_chunk, const __u8 *data,
+				yaffs_spare *spare)
+{
+	if (nand_chunk < dev->param.start_block * dev->param.chunks_per_block) {
+		T(YAFFS_TRACE_ERROR,
+		  (TSTR("**>> yaffs chunk %d is not valid" TENDSTR),
+		   nand_chunk));
+		return YAFFS_FAIL;
+	}
+
+	return dev->param.write_chunk_fn(dev, nand_chunk, data, spare);
+}
+
+static int yaffs_rd_chunk_nand(struct yaffs_dev_s *dev,
+				   int nand_chunk,
+				   __u8 *data,
+				   yaffs_spare *spare,
+				   yaffs_ecc_result *ecc_result,
+				   int correct_errors)
+{
+	int ret_val;
+	yaffs_spare local_spare;
+
+	if (!spare && data) {
+		/* If we don't have a real spare, then we use a local one. */
+		/* Need this for the calculation of the ecc */
+		spare = &local_spare;
+	}
+
+	if (!dev->param.use_nand_ecc) {
+		ret_val = dev->param.read_chunk_fn(dev, nand_chunk, data, spare);
+		if (data && correct_errors) {
+			/* Do ECC correction */
+			/* Todo handle any errors */
+			int ecc_result1, ecc_result2;
+			__u8 calc_ecc[3];
+
+			yaffs_ecc_cacl(data, calc_ecc);
+			ecc_result1 =
+			    yaffs_ecc_correct(data, spare->ecc1, calc_ecc);
+			yaffs_ecc_cacl(&data[256], calc_ecc);
+			ecc_result2 =
+			    yaffs_ecc_correct(&data[256], spare->ecc2, calc_ecc);
+
+			if (ecc_result1 > 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>yaffs ecc error fix performed on chunk %d:0"
+				    TENDSTR), nand_chunk));
+				dev->n_ecc_fixed++;
+			} else if (ecc_result1 < 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>yaffs ecc error unfixed on chunk %d:0"
+				    TENDSTR), nand_chunk));
+				dev->n_ecc_unfixed++;
+			}
+
+			if (ecc_result2 > 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>yaffs ecc error fix performed on chunk %d:1"
+				    TENDSTR), nand_chunk));
+				dev->n_ecc_fixed++;
+			} else if (ecc_result2 < 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>yaffs ecc error unfixed on chunk %d:1"
+				    TENDSTR), nand_chunk));
+				dev->n_ecc_unfixed++;
+			}
+
+			if (ecc_result1 || ecc_result2) {
+				/* We had a data problem on this page */
+				yaffs_handle_rd_data_error(dev, nand_chunk);
+			}
+
+			if (ecc_result1 < 0 || ecc_result2 < 0)
+				*ecc_result = YAFFS_ECC_RESULT_UNFIXED;
+			else if (ecc_result1 > 0 || ecc_result2 > 0)
+				*ecc_result = YAFFS_ECC_RESULT_FIXED;
+			else
+				*ecc_result = YAFFS_ECC_RESULT_NO_ERROR;
+		}
+	} else {
+		/* Must allocate enough memory for spare+2*sizeof(int) */
+		/* for ecc results from device. */
+		struct yaffs_nand_spare nspare;
+
+		memset(&nspare, 0, sizeof(nspare));
+
+		ret_val = dev->param.read_chunk_fn(dev, nand_chunk, data,
+					(yaffs_spare *) &nspare);
+		memcpy(spare, &nspare, sizeof(yaffs_spare));
+		if (data && correct_errors) {
+			if (nspare.eccres1 > 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>mtd ecc error fix performed on chunk %d:0"
+				    TENDSTR), nand_chunk));
+			} else if (nspare.eccres1 < 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>mtd ecc error unfixed on chunk %d:0"
+				    TENDSTR), nand_chunk));
+			}
+
+			if (nspare.eccres2 > 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>mtd ecc error fix performed on chunk %d:1"
+				    TENDSTR), nand_chunk));
+			} else if (nspare.eccres2 < 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>mtd ecc error unfixed on chunk %d:1"
+				    TENDSTR), nand_chunk));
+			}
+
+			if (nspare.eccres1 || nspare.eccres2) {
+				/* We had a data problem on this page */
+				yaffs_handle_rd_data_error(dev, nand_chunk);
+			}
+
+			if (nspare.eccres1 < 0 || nspare.eccres2 < 0)
+				*ecc_result = YAFFS_ECC_RESULT_UNFIXED;
+			else if (nspare.eccres1 > 0 || nspare.eccres2 > 0)
+				*ecc_result = YAFFS_ECC_RESULT_FIXED;
+			else
+				*ecc_result = YAFFS_ECC_RESULT_NO_ERROR;
+
+		}
+	}
+	return ret_val;
+}
+
+#ifdef NOTYET
+static int yaffs_check_chunk_erased(struct yaffs_dev_s *dev,
+				  int nand_chunk)
+{
+	static int init;
+	static __u8 cmpbuf[YAFFS_BYTES_PER_CHUNK];
+	static __u8 data[YAFFS_BYTES_PER_CHUNK];
+	/* Might as well always allocate the larger size for */
+	/* dev->param.use_nand_ecc == true; */
+	static __u8 spare[sizeof(struct yaffs_nand_spare)];
+
+	dev->param.read_chunk_fn(dev, nand_chunk, data, (yaffs_spare *) spare);
+
+	if (!init) {
+		memset(cmpbuf, 0xff, YAFFS_BYTES_PER_CHUNK);
+		init = 1;
+	}
+
+	if (memcmp(cmpbuf, data, YAFFS_BYTES_PER_CHUNK))
+		return YAFFS_FAIL;
+	if (memcmp(cmpbuf, spare, 16))
+		return YAFFS_FAIL;
+
+	return YAFFS_OK;
+
+}
+#endif
+
+/*
+ * Functions for robustisizing
+ */
+
+static void yaffs_handle_rd_data_error(yaffs_dev_t *dev, int nand_chunk)
+{
+	int flash_block = nand_chunk / dev->param.chunks_per_block;
+
+	/* Mark the block for retirement */
+	yaffs_get_block_info(dev, flash_block + dev->block_offset)->needs_retiring = 1;
+	T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
+	  (TSTR("**>>Block %d marked for retirement" TENDSTR), flash_block));
+
+	/* TODO:
+	 * Just do a garbage collection on the affected block
+	 * then retire the block
+	 * NB recursion
+	 */
+}
+
+#ifdef NOTYET
+static void yaffs_check_written_block(yaffs_dev_t *dev, int nand_chunk)
+{
+}
+
+static void yaffs_handle_chunk_wr_ok(yaffs_dev_t *dev, int nand_chunk,
+				     const __u8 *data,
+				     const yaffs_spare *spare)
+{
+}
+
+static void yaffs_handle_chunk_update(yaffs_dev_t *dev, int nand_chunk,
+				    const yaffs_spare *spare)
+{
+}
+
+static void yaffs_handle_chunk_wr_error(yaffs_dev_t *dev, int nand_chunk)
+{
+	int flash_block = nand_chunk / dev->param.chunks_per_block;
+
+	/* Mark the block for retirement */
+	yaffs_get_block_info(dev, flash_block)->needs_retiring = 1;
+	/* Delete the chunk */
+	yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
+}
+
+static int yaffs_verify_cmp(const __u8 *d0, const __u8 *d1,
+			       const yaffs_spare *s0, const yaffs_spare *s1)
+{
+
+	if (memcmp(d0, d1, YAFFS_BYTES_PER_CHUNK) != 0 ||
+	    s0->tb0 != s1->tb0 ||
+	    s0->tb1 != s1->tb1 ||
+	    s0->tb2 != s1->tb2 ||
+	    s0->tb3 != s1->tb3 ||
+	    s0->tb4 != s1->tb4 ||
+	    s0->tb5 != s1->tb5 ||
+	    s0->tb6 != s1->tb6 ||
+	    s0->tb7 != s1->tb7 ||
+	    s0->ecc1[0] != s1->ecc1[0] ||
+	    s0->ecc1[1] != s1->ecc1[1] ||
+	    s0->ecc1[2] != s1->ecc1[2] ||
+	    s0->ecc2[0] != s1->ecc2[0] ||
+	    s0->ecc2[1] != s1->ecc2[1] || s0->ecc2[2] != s1->ecc2[2]) {
+		return 0;
+	}
+
+	return 1;
+}
+#endif				/* NOTYET */
+
+int yaffs_tags_compat_wr(yaffs_dev_t *dev,
+						int nand_chunk,
+						const __u8 *data,
+						const yaffs_ext_tags *ext_tags)
+{
+	yaffs_spare spare;
+	yaffs_tags_t tags;
+
+	yaffs_spare_init(&spare);
+
+	if (ext_tags->is_deleted)
+		spare.page_status = 0;
+	else {
+		tags.obj_id = ext_tags->obj_id;
+		tags.chunk_id = ext_tags->chunk_id;
+
+		tags.n_bytes_lsb = ext_tags->n_bytes & 0x3ff;
+
+		if (dev->data_bytes_per_chunk >= 1024)
+			tags.n_bytes_msb = (ext_tags->n_bytes >> 10) & 3;
+		else
+			tags.n_bytes_msb = 3;
+
+
+		tags.serial_number = ext_tags->serial_number;
+
+		if (!dev->param.use_nand_ecc && data)
+			yaffs_calc_ecc(data, &spare);
+
+		yaffs_load_tags_to_spare(&spare, &tags);
+
+	}
+
+	return yaffs_wr_nand(dev, nand_chunk, data, &spare);
+}
+
+int yaffs_tags_compat_rd(yaffs_dev_t *dev,
+						     int nand_chunk,
+						     __u8 *data,
+						     yaffs_ext_tags *ext_tags)
+{
+
+	yaffs_spare spare;
+	yaffs_tags_t tags;
+	yaffs_ecc_result ecc_result = YAFFS_ECC_RESULT_UNKNOWN;
+
+	static yaffs_spare spare_ff;
+	static int init;
+
+	if (!init) {
+		memset(&spare_ff, 0xFF, sizeof(spare_ff));
+		init = 1;
+	}
+
+	if (yaffs_rd_chunk_nand
+	    (dev, nand_chunk, data, &spare, &ecc_result, 1)) {
+		/* ext_tags may be NULL */
+		if (ext_tags) {
+
+			int deleted =
+			    (yaffs_count_bits(spare.page_status) < 7) ? 1 : 0;
+
+			ext_tags->is_deleted = deleted;
+			ext_tags->ecc_result = ecc_result;
+			ext_tags->block_bad = 0;	/* We're reading it */
+			/* therefore it is not a bad block */
+			ext_tags->chunk_used =
+			    (memcmp(&spare_ff, &spare, sizeof(spare_ff)) !=
+			     0) ? 1 : 0;
+
+			if (ext_tags->chunk_used) {
+				yaffs_get_tags_from_spare(dev, &spare, &tags);
+
+				ext_tags->obj_id = tags.obj_id;
+				ext_tags->chunk_id = tags.chunk_id;
+				ext_tags->n_bytes = tags.n_bytes_lsb;
+
+				if (dev->data_bytes_per_chunk >= 1024)
+					ext_tags->n_bytes |= (((unsigned) tags.n_bytes_msb) << 10);
+
+				ext_tags->serial_number = tags.serial_number;
+			}
+		}
+
+		return YAFFS_OK;
+	} else {
+		return YAFFS_FAIL;
+	}
+}
+
+int yaffs_tags_compat_mark_bad(struct yaffs_dev_s *dev,
+					    int flash_block)
+{
+
+	yaffs_spare spare;
+
+	memset(&spare, 0xff, sizeof(yaffs_spare));
+
+	spare.block_status = 'Y';
+
+	yaffs_wr_nand(dev, flash_block * dev->param.chunks_per_block, NULL,
+			       &spare);
+	yaffs_wr_nand(dev, flash_block * dev->param.chunks_per_block + 1,
+			       NULL, &spare);
+
+	return YAFFS_OK;
+
+}
+
+int yaffs_tags_compat_query_block(struct yaffs_dev_s *dev,
+					  int block_no,
+					  yaffs_block_state_t *state,
+					  __u32 *seq_number)
+{
+
+	yaffs_spare spare0, spare1;
+	static yaffs_spare spare_ff;
+	static int init;
+	yaffs_ecc_result dummy;
+
+	if (!init) {
+		memset(&spare_ff, 0xFF, sizeof(spare_ff));
+		init = 1;
+	}
+
+	*seq_number = 0;
+
+	yaffs_rd_chunk_nand(dev, block_no * dev->param.chunks_per_block, NULL,
+				&spare0, &dummy, 1);
+	yaffs_rd_chunk_nand(dev, block_no * dev->param.chunks_per_block + 1, NULL,
+				&spare1, &dummy, 1);
+
+	if (yaffs_count_bits(spare0.block_status & spare1.block_status) < 7)
+		*state = YAFFS_BLOCK_STATE_DEAD;
+	else if (memcmp(&spare_ff, &spare0, sizeof(spare_ff)) == 0)
+		*state = YAFFS_BLOCK_STATE_EMPTY;
+	else
+		*state = YAFFS_BLOCK_STATE_NEEDS_SCANNING;
+
+	return YAFFS_OK;
+}
diff --git a/drivers/staging/yaffs2/yaffs_tagscompat.h b/drivers/staging/yaffs2/yaffs_tagscompat.h
new file mode 100644
index 0000000..889bf5f4
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_tagscompat.h
@@ -0,0 +1,39 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_TAGSCOMPAT_H__
+#define __YAFFS_TAGSCOMPAT_H__
+
+#include "yaffs_guts.h"
+int yaffs_tags_compat_wr(yaffs_dev_t *dev,
+						int nand_chunk,
+						const __u8 *data,
+						const yaffs_ext_tags *tags);
+int yaffs_tags_compat_rd(yaffs_dev_t *dev,
+						int nand_chunk,
+						__u8 *data,
+						yaffs_ext_tags *tags);
+int yaffs_tags_compat_mark_bad(struct yaffs_dev_s *dev,
+					    int block_no);
+int yaffs_tags_compat_query_block(struct yaffs_dev_s *dev,
+					  int block_no,
+					  yaffs_block_state_t *state,
+					  __u32 *seq_number);
+
+void yaffs_calc_tags_ecc(yaffs_tags_t *tags);
+int yaffs_check_tags_ecc(yaffs_tags_t *tags);
+int yaffs_count_bits(__u8 byte);
+
+#endif
-- 
1.7.3.2.146.gca209

Re: [PATCH 21/29] Staging: yaffs2: yaffs_tagscompact: Add files

[Jesper Juhl]

On Mon, 1 Nov 2010, Tracey Dent wrote:

> Adding files to yaffs2 directory.
> 
> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> ---
>  drivers/staging/yaffs2/yaffs_tagscompat.c |  539 +++++++++++++++++++++++++++++
>  drivers/staging/yaffs2/yaffs_tagscompat.h |   39 ++
>  2 files changed, 578 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/yaffs2/yaffs_tagscompat.c
>  create mode 100644 drivers/staging/yaffs2/yaffs_tagscompat.h
> 
> diff --git a/drivers/staging/yaffs2/yaffs_tagscompat.c b/drivers/staging/yaffs2/yaffs_tagscompat.c
> new file mode 100644
> index 0000000..1e910f2
> --- /dev/null
> +++ b/drivers/staging/yaffs2/yaffs_tagscompat.c
[snip]
> +int yaffs_count_bits(__u8 x)
> +{
> +	int ret_val;
> +	ret_val = yaffs_count_bits_table[x];
> +	return ret_val;

How about just getting rid of the unneeded temporary variable and just 
doing:

int yaffs_count_bits(__u8 x)
{
     return yaffs_count_bits_table[x];
}

??

[snip]
> +void yaffs_calc_tags_ecc(yaffs_tags_t *tags)
> +{
> +	/* Calculate an ecc */
> +
> +	unsigned char *b = ((yaffs_tags_union_t *) tags)->as_bytes;
> +	unsigned i, j;
> +	unsigned ecc = 0;
> +	unsigned bit = 0;
> +
> +	tags->ecc = 0;

tags->ecc is not touched between here

> +
> +	for (i = 0; i < 8; i++) {
> +		for (j = 1; j & 0xff; j <<= 1) {
> +			bit++;
> +			if (b[i] & j)
> +				ecc ^= bit;
> +		}
> +	}
> +
> +	tags->ecc = ecc;

and this assignment here, so the first 'tags->ecc = 0' assignment is 
pointless and should just go away IMHO.

> +int yaffs_tags_compat_wr(yaffs_dev_t *dev,
> +						int nand_chunk,
> +						const __u8 *data,
> +						const yaffs_ext_tags *ext_tags)
> +{
> +	yaffs_spare spare;
> +	yaffs_tags_t tags;
> +
> +	yaffs_spare_init(&spare);
> +
> +	if (ext_tags->is_deleted)
> +		spare.page_status = 0;
> +	else {

purely a minor style issue, but I believe the kernel coding style here is 
to put curly braces for both the 'if' and 'else' branches if either 
requires them, so

if (ext_tags->is_deleted) {
        spare.page_status = 0;
} else {
        ...
        ...
}


[snip]
> +int yaffs_tags_compat_rd(yaffs_dev_t *dev,
> +						     int nand_chunk,
> +						     __u8 *data,
> +						     yaffs_ext_tags *ext_tags)
> +{
> +
> +	yaffs_spare spare;
> +	yaffs_tags_t tags;
> +	yaffs_ecc_result ecc_result = YAFFS_ECC_RESULT_UNKNOWN;
> +
> +	static yaffs_spare spare_ff;
> +	static int init;
> +
> +	if (!init) {
> +		memset(&spare_ff, 0xFF, sizeof(spare_ff));
> +		init = 1;
> +	}
> +
> +	if (yaffs_rd_chunk_nand
> +	    (dev, nand_chunk, data, &spare, &ecc_result, 1)) {
> +		/* ext_tags may be NULL */
> +		if (ext_tags) {
> +
> +			int deleted =
> +			    (yaffs_count_bits(spare.page_status) < 7) ? 1 : 0;
> +
> +			ext_tags->is_deleted = deleted;
> +			ext_tags->ecc_result = ecc_result;
> +			ext_tags->block_bad = 0;	/* We're reading it */
> +			/* therefore it is not a bad block */
> +			ext_tags->chunk_used =
> +			    (memcmp(&spare_ff, &spare, sizeof(spare_ff)) !=
> +			     0) ? 1 : 0;
> +
> +			if (ext_tags->chunk_used) {
> +				yaffs_get_tags_from_spare(dev, &spare, &tags);
> +
> +				ext_tags->obj_id = tags.obj_id;
> +				ext_tags->chunk_id = tags.chunk_id;
> +				ext_tags->n_bytes = tags.n_bytes_lsb;
> +
> +				if (dev->data_bytes_per_chunk >= 1024)
> +					ext_tags->n_bytes |= (((unsigned) tags.n_bytes_msb) << 10);
> +
> +				ext_tags->serial_number = tags.serial_number;
> +			}
> +		}
> +
> +		return YAFFS_OK;
> +	} else {
> +		return YAFFS_FAIL;
> +	}
> +}

Indentation could be reduced with no negative effect by doing

if (!yaffs_rd_chunk_nand
         (dev, nand_chunk, data, &spare, &ecc_result, 1))
        return YAFFS_FAIL;
...rest of function...


> +int yaffs_tags_compat_mark_bad(struct yaffs_dev_s *dev,
> +					    int flash_block)
> +{
> +
> +	yaffs_spare spare;
> +
> +	memset(&spare, 0xff, sizeof(yaffs_spare));
> +

Why is memset() used directly here, but elsewhere the yaffs_spare_init() 
function is used?


-- 
Jesper Juhl <jj@chaosbits.net>             http://www.chaosbits.net/
Plain text mails only, please      http://www.expita.com/nomime.html
Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html

[PATCH 22/29] Staging: yaffs2: yaffs_tagsvalidity: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_tagsvalidity.c |   28 +++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_tagsvalidity.h |   24 +++++++++++++++++++++++
 2 files changed, 52 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_tagsvalidity.c
 create mode 100644 drivers/staging/yaffs2/yaffs_tagsvalidity.h

diff --git a/drivers/staging/yaffs2/yaffs_tagsvalidity.c b/drivers/staging/yaffs2/yaffs_tagsvalidity.c
new file mode 100644
index 0000000..787cdba
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_tagsvalidity.c
@@ -0,0 +1,28 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_tagsvalidity.h"
+
+void yaffs_init_tags(yaffs_ext_tags *tags)
+{
+	memset(tags, 0, sizeof(yaffs_ext_tags));
+	tags->validity1 = 0xAAAAAAAA;
+	tags->validty1 = 0x55555555;
+}
+
+int yaffs_validate_tags(yaffs_ext_tags *tags)
+{
+	return (tags->validity1 == 0xAAAAAAAA &&
+		tags->validty1 == 0x55555555);
+
+}
diff --git a/drivers/staging/yaffs2/yaffs_tagsvalidity.h b/drivers/staging/yaffs2/yaffs_tagsvalidity.h
new file mode 100644
index 0000000..085056c
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_tagsvalidity.h
@@ -0,0 +1,24 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+
+#ifndef __YAFFS_TAGS_VALIDITY_H__
+#define __YAFFS_TAGS_VALIDITY_H__
+
+#include "yaffs_guts.h"
+
+void yaffs_init_tags(yaffs_ext_tags *tags);
+int yaffs_validate_tags(yaffs_ext_tags *tags);
+#endif
-- 
1.7.3.2.146.gca209

[PATCH 23/29] Staging: yaffs2: yaffs_trace.h: Add file

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_trace.h |   60 ++++++++++++++++++++++++++++++++++
 1 files changed, 60 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_trace.h

diff --git a/drivers/staging/yaffs2/yaffs_trace.h b/drivers/staging/yaffs2/yaffs_trace.h
new file mode 100644
index 0000000..9fe7214
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_trace.h
@@ -0,0 +1,60 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+
+#ifndef __YTRACE_H__
+#define __YTRACE_H__
+
+extern unsigned int yaffs_trace_mask;
+extern unsigned int yaffs_wr_attempts;
+
+/*
+ * Tracing flags.
+ * The flags masked in YAFFS_TRACE_ALWAYS are always traced.
+ */
+
+#define YAFFS_TRACE_OS			0x00000002
+#define YAFFS_TRACE_ALLOCATE		0x00000004
+#define YAFFS_TRACE_SCAN		0x00000008
+#define YAFFS_TRACE_BAD_BLOCKS		0x00000010
+#define YAFFS_TRACE_ERASE		0x00000020
+#define YAFFS_TRACE_GC			0x00000040
+#define YAFFS_TRACE_WRITE		0x00000080
+#define YAFFS_TRACE_TRACING		0x00000100
+#define YAFFS_TRACE_DELETION		0x00000200
+#define YAFFS_TRACE_BUFFERS		0x00000400
+#define YAFFS_TRACE_NANDACCESS		0x00000800
+#define YAFFS_TRACE_GC_DETAIL		0x00001000
+#define YAFFS_TRACE_SCAN_DEBUG		0x00002000
+#define YAFFS_TRACE_MTD			0x00004000
+#define YAFFS_TRACE_CHECKPOINT		0x00008000
+
+#define YAFFS_TRACE_VERIFY		0x00010000
+#define YAFFS_TRACE_VERIFY_NAND		0x00020000
+#define YAFFS_TRACE_VERIFY_FULL		0x00040000
+#define YAFFS_TRACE_VERIFY_ALL		0x000F0000
+
+#define YAFFS_TRACE_SYNC		0x00100000
+#define YAFFS_TRACE_BACKGROUND		0x00200000
+#define YAFFS_TRACE_LOCK		0x00400000
+
+#define YAFFS_TRACE_ERROR		0x40000000
+#define YAFFS_TRACE_BUG			0x80000000
+#define YAFFS_TRACE_ALWAYS		0xF0000000
+
+
+#define T(mask, p) do { if ((mask) & (yaffs_trace_mask | YAFFS_TRACE_ALWAYS)) TOUT(p); } while (0)
+
+#endif
-- 
1.7.3.2.146.gca209

[PATCH 24/29] Staging: yaffs2: yaffs_verify: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_verify.c |  631 +++++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_verify.h |   41 +++
 2 files changed, 672 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_verify.c
 create mode 100644 drivers/staging/yaffs2/yaffs_verify.h

diff --git a/drivers/staging/yaffs2/yaffs_verify.c b/drivers/staging/yaffs2/yaffs_verify.c
new file mode 100644
index 0000000..89e730b
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_verify.c
@@ -0,0 +1,631 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+
+#include "yaffs_verify.h"
+#include "yaffs_trace.h"
+#include "yaffs_bitmap.h"
+#include "yaffs_getblockinfo.h"
+#include "yaffs_nand.h"
+
+int yaffs_skip_verification(yaffs_dev_t *dev)
+{
+	dev=dev;
+	return !(yaffs_trace_mask & (YAFFS_TRACE_VERIFY | YAFFS_TRACE_VERIFY_FULL));
+}
+
+static int yaffs_skip_full_verification(yaffs_dev_t *dev)
+{
+	dev=dev;
+	return !(yaffs_trace_mask & (YAFFS_TRACE_VERIFY_FULL));
+}
+
+static int yaffs_skip_nand_verification(yaffs_dev_t *dev)
+{
+	dev=dev;
+	return !(yaffs_trace_mask & (YAFFS_TRACE_VERIFY_NAND));
+}
+
+
+static const char *block_state_name[] = {
+"Unknown",
+"Needs scanning",
+"Scanning",
+"Empty",
+"Allocating",
+"Full",
+"Dirty",
+"Checkpoint",
+"Collecting",
+"Dead"
+};
+
+
+void yaffs_verify_blk(yaffs_dev_t *dev, yaffs_block_info_t *bi, int n)
+{
+	int actually_used;
+	int in_use;
+
+	if (yaffs_skip_verification(dev))
+		return;
+
+	/* Report illegal runtime states */
+	if (bi->block_state >= YAFFS_NUMBER_OF_BLOCK_STATES)
+		T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has undefined state %d"TENDSTR), n, bi->block_state));
+
+	switch (bi->block_state) {
+	case YAFFS_BLOCK_STATE_UNKNOWN:
+	case YAFFS_BLOCK_STATE_SCANNING:
+	case YAFFS_BLOCK_STATE_NEEDS_SCANNING:
+		T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has bad run-state %s"TENDSTR),
+		n, block_state_name[bi->block_state]));
+	}
+
+	/* Check pages in use and soft deletions are legal */
+
+	actually_used = bi->pages_in_use - bi->soft_del_pages;
+
+	if (bi->pages_in_use < 0 || bi->pages_in_use > dev->param.chunks_per_block ||
+	   bi->soft_del_pages < 0 || bi->soft_del_pages > dev->param.chunks_per_block ||
+	   actually_used < 0 || actually_used > dev->param.chunks_per_block)
+		T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has illegal values pages_in_used %d soft_del_pages %d"TENDSTR),
+		n, bi->pages_in_use, bi->soft_del_pages));
+
+
+	/* Check chunk bitmap legal */
+	in_use = yaffs_count_chunk_bits(dev, n);
+	if (in_use != bi->pages_in_use)
+		T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has inconsistent values pages_in_use %d counted chunk bits %d"TENDSTR),
+			n, bi->pages_in_use, in_use));
+
+}
+
+
+
+void yaffs_verify_collected_blk(yaffs_dev_t *dev, yaffs_block_info_t *bi, int n)
+{
+	yaffs_verify_blk(dev, bi, n);
+
+	/* After collection the block should be in the erased state */
+
+	if (bi->block_state != YAFFS_BLOCK_STATE_COLLECTING &&
+			bi->block_state != YAFFS_BLOCK_STATE_EMPTY) {
+		T(YAFFS_TRACE_ERROR, (TSTR("Block %d is in state %d after gc, should be erased"TENDSTR),
+			n, bi->block_state));
+	}
+}
+
+void yaffs_verify_blocks(yaffs_dev_t *dev)
+{
+	int i;
+	int state_count[YAFFS_NUMBER_OF_BLOCK_STATES];
+	int illegal_states = 0;
+
+	if (yaffs_skip_verification(dev))
+		return;
+
+	memset(state_count, 0, sizeof(state_count));
+
+	for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
+		yaffs_block_info_t *bi = yaffs_get_block_info(dev, i);
+		yaffs_verify_blk(dev, bi, i);
+
+		if (bi->block_state < YAFFS_NUMBER_OF_BLOCK_STATES)
+			state_count[bi->block_state]++;
+		else
+			illegal_states++;
+	}
+
+	T(YAFFS_TRACE_VERIFY, (TSTR(""TENDSTR)));
+	T(YAFFS_TRACE_VERIFY, (TSTR("Block summary"TENDSTR)));
+
+	T(YAFFS_TRACE_VERIFY, (TSTR("%d blocks have illegal states"TENDSTR), illegal_states));
+	if (state_count[YAFFS_BLOCK_STATE_ALLOCATING] > 1)
+		T(YAFFS_TRACE_VERIFY, (TSTR("Too many allocating blocks"TENDSTR)));
+
+	for (i = 0; i < YAFFS_NUMBER_OF_BLOCK_STATES; i++)
+		T(YAFFS_TRACE_VERIFY,
+		  (TSTR("%s %d blocks"TENDSTR),
+		  block_state_name[i], state_count[i]));
+
+	if (dev->blocks_in_checkpt != state_count[YAFFS_BLOCK_STATE_CHECKPOINT])
+		T(YAFFS_TRACE_VERIFY,
+		 (TSTR("Checkpoint block count wrong dev %d count %d"TENDSTR),
+		 dev->blocks_in_checkpt, state_count[YAFFS_BLOCK_STATE_CHECKPOINT]));
+
+	if (dev->n_erased_blocks != state_count[YAFFS_BLOCK_STATE_EMPTY])
+		T(YAFFS_TRACE_VERIFY,
+		 (TSTR("Erased block count wrong dev %d count %d"TENDSTR),
+		 dev->n_erased_blocks, state_count[YAFFS_BLOCK_STATE_EMPTY]));
+
+	if (state_count[YAFFS_BLOCK_STATE_COLLECTING] > 1)
+		T(YAFFS_TRACE_VERIFY,
+		 (TSTR("Too many collecting blocks %d (max is 1)"TENDSTR),
+		 state_count[YAFFS_BLOCK_STATE_COLLECTING]));
+
+	T(YAFFS_TRACE_VERIFY, (TSTR(""TENDSTR)));
+
+}
+
+/*
+ * Verify the object header. oh must be valid, but obj and tags may be NULL in which
+ * case those tests will not be performed.
+ */
+void yaffs_verify_oh(yaffs_obj_t *obj, yaffs_obj_header *oh, yaffs_ext_tags *tags, int parent_check)
+{
+	if (obj && yaffs_skip_verification(obj->my_dev))
+		return;
+
+	if (!(tags && obj && oh)) {
+		T(YAFFS_TRACE_VERIFY,
+				(TSTR("Verifying object header tags %p obj %p oh %p"TENDSTR),
+				tags, obj, oh));
+		return;
+	}
+
+	if (oh->type <= YAFFS_OBJECT_TYPE_UNKNOWN ||
+			oh->type > YAFFS_OBJECT_TYPE_MAX)
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d header type is illegal value 0x%x"TENDSTR),
+			tags->obj_id, oh->type));
+
+	if (tags->obj_id != obj->obj_id)
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d header mismatch obj_id %d"TENDSTR),
+			tags->obj_id, obj->obj_id));
+
+
+	/*
+	 * Check that the object's parent ids match if parent_check requested.
+	 *
+	 * Tests do not apply to the root object.
+	 */
+
+	if (parent_check && tags->obj_id > 1 && !obj->parent)
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d header mismatch parent_id %d obj->parent is NULL"TENDSTR),
+			tags->obj_id, oh->parent_obj_id));
+
+	if (parent_check && obj->parent &&
+			oh->parent_obj_id != obj->parent->obj_id &&
+			(oh->parent_obj_id != YAFFS_OBJECTID_UNLINKED ||
+			obj->parent->obj_id != YAFFS_OBJECTID_DELETED))
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d header mismatch parent_id %d parent_obj_id %d"TENDSTR),
+			tags->obj_id, oh->parent_obj_id, obj->parent->obj_id));
+
+	if (tags->obj_id > 1 && oh->name[0] == 0) /* Null name */
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d header name is NULL"TENDSTR),
+			obj->obj_id));
+
+	if (tags->obj_id > 1 && ((__u8)(oh->name[0])) == 0xff) /* Trashed name */
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d header name is 0xFF"TENDSTR),
+			obj->obj_id));
+}
+
+
+#if 0
+/* Not being used, but don't want to throw away yet */
+int yaffs_verify_tnode_worker(yaffs_obj_t *obj, yaffs_tnode_t *tn,
+					__u32 level, int chunk_offset)
+{
+	int i;
+	yaffs_dev_t *dev = obj->my_dev;
+	int ok = 1;
+
+	if (tn) {
+		if (level > 0) {
+
+			for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++) {
+				if (tn->internal[i]) {
+					ok = yaffs_verify_tnode_worker(obj,
+							tn->internal[i],
+							level - 1,
+							(chunk_offset<<YAFFS_TNODES_INTERNAL_BITS) + i);
+				}
+			}
+		} else if (level == 0) {
+			yaffs_ext_tags tags;
+			__u32 obj_id = obj->obj_id;
+
+			chunk_offset <<=  YAFFS_TNODES_LEVEL0_BITS;
+
+			for (i = 0; i < YAFFS_NTNODES_LEVEL0; i++) {
+				__u32 the_chunk = yaffs_get_group_base(dev, tn, i);
+
+				if (the_chunk > 0) {
+					/* T(~0,(TSTR("verifying (%d:%d) %d"TENDSTR),tags.obj_id,tags.chunk_id,the_chunk)); */
+					yaffs_rd_chunk_tags_nand(dev, the_chunk, NULL, &tags);
+					if (tags.obj_id != obj_id || tags.chunk_id != chunk_offset) {
+						T(~0, (TSTR("Object %d chunk_id %d NAND mismatch chunk %d tags (%d:%d)"TENDSTR),
+							obj_id, chunk_offset, the_chunk,
+							tags.obj_id, tags.chunk_id));
+					}
+				}
+				chunk_offset++;
+			}
+		}
+	}
+
+	return ok;
+
+}
+
+#endif
+
+void yaffs_verify_file(yaffs_obj_t *obj)
+{
+	int required_depth;
+	int actual_depth;
+	__u32 last_chunk;
+	__u32 x;
+	__u32 i;
+	yaffs_dev_t *dev;
+	yaffs_ext_tags tags;
+	yaffs_tnode_t *tn;
+	__u32 obj_id;
+
+	if (!obj)
+		return;
+
+	if (yaffs_skip_verification(obj->my_dev))
+		return;
+
+	dev = obj->my_dev;
+	obj_id = obj->obj_id;
+
+	/* Check file size is consistent with tnode depth */
+	last_chunk =  obj->variant.file_variant.file_size / dev->data_bytes_per_chunk + 1;
+	x = last_chunk >> YAFFS_TNODES_LEVEL0_BITS;
+	required_depth = 0;
+	while (x > 0) {
+		x >>= YAFFS_TNODES_INTERNAL_BITS;
+		required_depth++;
+	}
+
+	actual_depth = obj->variant.file_variant.top_level;
+
+	/* Check that the chunks in the tnode tree are all correct.
+	 * We do this by scanning through the tnode tree and
+	 * checking the tags for every chunk match.
+	 */
+
+	if (yaffs_skip_nand_verification(dev))
+		return;
+
+	for (i = 1; i <= last_chunk; i++) {
+		tn = yaffs_find_tnode_0(dev, &obj->variant.file_variant, i);
+
+		if (tn) {
+			__u32 the_chunk = yaffs_get_group_base(dev, tn, i);
+			if (the_chunk > 0) {
+				/* T(~0,(TSTR("verifying (%d:%d) %d"TENDSTR),obj_id,i,the_chunk)); */
+				yaffs_rd_chunk_tags_nand(dev, the_chunk, NULL, &tags);
+				if (tags.obj_id != obj_id || tags.chunk_id != i) {
+					T(~0, (TSTR("Object %d chunk_id %d NAND mismatch chunk %d tags (%d:%d)"TENDSTR),
+						obj_id, i, the_chunk,
+						tags.obj_id, tags.chunk_id));
+				}
+			}
+		}
+	}
+}
+
+
+void yaffs_verify_link(yaffs_obj_t *obj)
+{
+	if (obj && yaffs_skip_verification(obj->my_dev))
+		return;
+
+	/* Verify sane equivalent object */
+}
+
+void yaffs_verify_symlink(yaffs_obj_t *obj)
+{
+	if (obj && yaffs_skip_verification(obj->my_dev))
+		return;
+
+	/* Verify symlink string */
+}
+
+void yaffs_verify_special(yaffs_obj_t *obj)
+{
+	if (obj && yaffs_skip_verification(obj->my_dev))
+		return;
+}
+
+void yaffs_verify_obj(yaffs_obj_t *obj)
+{
+	yaffs_dev_t *dev;
+
+	__u32 chunk_min;
+	__u32 chunk_max;
+
+	__u32 chunk_id_ok;
+	__u32 chunk_in_range;
+	__u32 chunk_wrongly_deleted;
+	__u32 chunk_valid;
+
+	if (!obj)
+		return;
+
+	if (obj->being_created)
+		return;
+
+	dev = obj->my_dev;
+
+	if (yaffs_skip_verification(dev))
+		return;
+
+	/* Check sane object header chunk */
+
+	chunk_min = dev->internal_start_block * dev->param.chunks_per_block;
+	chunk_max = (dev->internal_end_block+1) * dev->param.chunks_per_block - 1;
+
+	chunk_in_range = (((unsigned)(obj->hdr_chunk)) >= chunk_min && 
+	                ((unsigned)(obj->hdr_chunk)) <= chunk_max);
+	chunk_id_ok = chunk_in_range || (obj->hdr_chunk == 0);
+	chunk_valid = chunk_in_range &&
+			yaffs_check_chunk_bit(dev,
+					obj->hdr_chunk / dev->param.chunks_per_block,
+					obj->hdr_chunk % dev->param.chunks_per_block);
+	chunk_wrongly_deleted = chunk_in_range && !chunk_valid;
+
+	if (!obj->fake &&
+			(!chunk_id_ok || chunk_wrongly_deleted)) {
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d has chunk_id %d %s %s"TENDSTR),
+			obj->obj_id, obj->hdr_chunk,
+			chunk_id_ok ? "" : ",out of range",
+			chunk_wrongly_deleted ? ",marked as deleted" : ""));
+	}
+
+	if (chunk_valid && !yaffs_skip_nand_verification(dev)) {
+		yaffs_ext_tags tags;
+		yaffs_obj_header *oh;
+		__u8 *buffer = yaffs_get_temp_buffer(dev, __LINE__);
+
+		oh = (yaffs_obj_header *)buffer;
+
+		yaffs_rd_chunk_tags_nand(dev, obj->hdr_chunk, buffer,
+				&tags);
+
+		yaffs_verify_oh(obj, oh, &tags, 1);
+
+		yaffs_release_temp_buffer(dev, buffer, __LINE__);
+	}
+
+	/* Verify it has a parent */
+	if (obj && !obj->fake &&
+			(!obj->parent || obj->parent->my_dev != dev)) {
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d has parent pointer %p which does not look like an object"TENDSTR),
+			obj->obj_id, obj->parent));
+	}
+
+	/* Verify parent is a directory */
+	if (obj->parent && obj->parent->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d's parent is not a directory (type %d)"TENDSTR),
+			obj->obj_id, obj->parent->variant_type));
+	}
+
+	switch (obj->variant_type) {
+	case YAFFS_OBJECT_TYPE_FILE:
+		yaffs_verify_file(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_SYMLINK:
+		yaffs_verify_symlink(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_DIRECTORY:
+		yaffs_verify_dir(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_HARDLINK:
+		yaffs_verify_link(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_SPECIAL:
+		yaffs_verify_special(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_UNKNOWN:
+	default:
+		T(YAFFS_TRACE_VERIFY,
+		(TSTR("Obj %d has illegaltype %d"TENDSTR),
+		obj->obj_id, obj->variant_type));
+		break;
+	}
+}
+
+void yaffs_verify_objects(yaffs_dev_t *dev)
+{
+	yaffs_obj_t *obj;
+	int i;
+	struct ylist_head *lh;
+
+	if (yaffs_skip_verification(dev))
+		return;
+
+	/* Iterate through the objects in each hash entry */
+
+	for (i = 0; i <  YAFFS_NOBJECT_BUCKETS; i++) {
+		ylist_for_each(lh, &dev->obj_bucket[i].list) {
+			if (lh) {
+				obj = ylist_entry(lh, yaffs_obj_t, hash_link);
+				yaffs_verify_obj(obj);
+			}
+		}
+	}
+}
+
+
+void yaffs_verify_obj_in_dir(yaffs_obj_t *obj)
+{
+	struct ylist_head *lh;
+	yaffs_obj_t *list_obj;
+
+	int count = 0;
+
+	if (!obj) {
+		T(YAFFS_TRACE_ALWAYS, (TSTR("No object to verify" TENDSTR)));
+		YBUG();
+		return;
+	}
+
+	if (yaffs_skip_verification(obj->my_dev))
+		return;
+
+	if (!obj->parent) {
+		T(YAFFS_TRACE_ALWAYS, (TSTR("Object does not have parent" TENDSTR)));
+		YBUG();
+		return;
+	}
+
+	if (obj->parent->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
+		T(YAFFS_TRACE_ALWAYS, (TSTR("Parent is not directory" TENDSTR)));
+		YBUG();
+	}
+
+	/* Iterate through the objects in each hash entry */
+
+	ylist_for_each(lh, &obj->parent->variant.dir_variant.children) {
+		if (lh) {
+			list_obj = ylist_entry(lh, yaffs_obj_t, siblings);
+			yaffs_verify_obj(list_obj);
+			if (obj == list_obj)
+				count++;
+		}
+	 }
+
+	if (count != 1) {
+		T(YAFFS_TRACE_ALWAYS, (TSTR("Object in directory %d times" TENDSTR), count));
+		YBUG();
+	}
+}
+
+void yaffs_verify_dir(yaffs_obj_t *directory)
+{
+	struct ylist_head *lh;
+	yaffs_obj_t *list_obj;
+
+	if (!directory) {
+		YBUG();
+		return;
+	}
+
+	if (yaffs_skip_full_verification(directory->my_dev))
+		return;
+
+	if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
+		T(YAFFS_TRACE_ALWAYS,
+		(TSTR("Directory has wrong type: %d" TENDSTR),
+		directory->variant_type));
+		YBUG();
+	}
+
+	/* Iterate through the objects in each hash entry */
+
+	ylist_for_each(lh, &directory->variant.dir_variant.children) {
+		if (lh) {
+			list_obj = ylist_entry(lh, yaffs_obj_t, siblings);
+			if (list_obj->parent != directory) {
+				T(YAFFS_TRACE_ALWAYS, (
+				TSTR("Object in directory list has wrong parent %p" TENDSTR),
+				list_obj->parent));
+				YBUG();
+			}
+			yaffs_verify_obj_in_dir(list_obj);
+		}
+	}
+}
+
+static int yaffs_free_verification_failures;
+
+void yaffs_verify_free_chunks(yaffs_dev_t *dev)
+{
+	int counted;
+	int difference;
+
+	if (yaffs_skip_verification(dev))
+		return;
+
+	counted = yaffs_count_free_chunks(dev);
+
+	difference = dev->n_free_chunks - counted;
+
+	if (difference) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR("Freechunks verification failure %d %d %d" TENDSTR),
+		   dev->n_free_chunks, counted, difference));
+		yaffs_free_verification_failures++;
+	}
+}
+
+int yaffs_verify_file_sane(yaffs_obj_t *in)
+{
+#if 0
+	int chunk;
+	int n_chunks;
+	int file_size;
+	int failed = 0;
+	int obj_id;
+	yaffs_tnode_t *tn;
+	yaffs_tags_t local_tags;
+	yaffs_tags_t *tags = &local_tags;
+	int the_chunk;
+	int is_deleted;
+
+	if (in->variant_type != YAFFS_OBJECT_TYPE_FILE)
+		return YAFFS_FAIL;
+
+	obj_id = in->obj_id;
+	file_size = in->variant.file_variant.file_size;
+	n_chunks =
+	    (file_size + in->my_dev->data_bytes_per_chunk - 1) / in->my_dev->data_bytes_per_chunk;
+
+	for (chunk = 1; chunk <= n_chunks; chunk++) {
+		tn = yaffs_find_tnode_0(in->my_dev, &in->variant.file_variant,
+					   chunk);
+
+		if (tn) {
+
+			the_chunk = yaffs_get_group_base(dev, tn, chunk);
+
+			if (yaffs_check_chunk_bits
+			    (dev, the_chunk / dev->param.chunks_per_block,
+			     the_chunk % dev->param.chunks_per_block)) {
+
+				yaffs_rd_chunk_tags_nand(in->my_dev, the_chunk,
+							    tags,
+							    &is_deleted);
+				if (yaffs_tags_match
+				    (tags, in->obj_id, chunk, is_deleted)) {
+					/* found it; */
+
+				}
+			} else {
+
+				failed = 1;
+			}
+
+		} else {
+			/* T(("No level 0 found for %d\n", chunk)); */
+		}
+	}
+
+	return failed ? YAFFS_FAIL : YAFFS_OK;
+#else
+	in=in;
+	return YAFFS_OK;
+#endif
+}
diff --git a/drivers/staging/yaffs2/yaffs_verify.h b/drivers/staging/yaffs2/yaffs_verify.h
new file mode 100644
index 0000000..6118afd
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_verify.h
@@ -0,0 +1,41 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_VERIFY_H__
+#define __YAFFS_VERIFY_H__
+
+#include "yaffs_guts.h"
+
+void yaffs_verify_blk(yaffs_dev_t *dev, yaffs_block_info_t *bi, int n);
+void yaffs_verify_collected_blk(yaffs_dev_t *dev, yaffs_block_info_t *bi, int n);
+void yaffs_verify_blocks(yaffs_dev_t *dev);
+
+void yaffs_verify_oh(yaffs_obj_t *obj, yaffs_obj_header *oh, yaffs_ext_tags *tags, int parent_check);
+void yaffs_verify_file(yaffs_obj_t *obj);
+void yaffs_verify_link(yaffs_obj_t *obj);
+void yaffs_verify_symlink(yaffs_obj_t *obj);
+void yaffs_verify_special(yaffs_obj_t *obj);
+void yaffs_verify_obj(yaffs_obj_t *obj);
+void yaffs_verify_objects(yaffs_dev_t *dev);
+void yaffs_verify_obj_in_dir(yaffs_obj_t *obj);
+void yaffs_verify_dir(yaffs_obj_t *directory);
+void yaffs_verify_free_chunks(yaffs_dev_t *dev);
+
+int yaffs_verify_file_sane(yaffs_obj_t *obj);
+
+int yaffs_skip_verification(yaffs_dev_t *dev);
+
+#endif
+
-- 
1.7.3.2.146.gca209

Re: [PATCH 24/29] Staging: yaffs2: yaffs_verify: Add files

[Jesper Juhl]

On Mon, 1 Nov 2010, Tracey Dent wrote:

> Adding files to yaffs2 directory.
> 
> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> ---
>  drivers/staging/yaffs2/yaffs_verify.c |  631 +++++++++++++++++++++++++++++++++
>  drivers/staging/yaffs2/yaffs_verify.h |   41 +++
>  2 files changed, 672 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/yaffs2/yaffs_verify.c
>  create mode 100644 drivers/staging/yaffs2/yaffs_verify.h
> 
> diff --git a/drivers/staging/yaffs2/yaffs_verify.c b/drivers/staging/yaffs2/yaffs_verify.c
> new file mode 100644
> index 0000000..89e730b
> --- /dev/null
> +++ b/drivers/staging/yaffs2/yaffs_verify.c
...
> +#if 0

Why are you trying to merge new code that's under '#if 0' (and not just 
here, but elsewhere as well)?
Either it shouldn't be here, in which case it should just be omitted from 
the patch, or it needs to be here eventually in which case it should be 
fixed up so the '#if 0' can go away or simply just be added later when it 
has been fixed up.

 > +/* Not being used, but don't want to throw away yet 
*/ > +int yaffs_verify_tnode_worker(yaffs_obj_t *obj, yaffs_tnode_t *tn,
> +					__u32 level, int chunk_offset)
> +{
> +	int i;
> +	yaffs_dev_t *dev = obj->my_dev;
> +	int ok = 1;
> +
> +	if (tn) {
> +		if (level > 0) {
> +
> +			for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++) {
> +				if (tn->internal[i]) {
> +					ok = yaffs_verify_tnode_worker(obj,
> +							tn->internal[i],
> +							level - 1,
> +							(chunk_offset<<YAFFS_TNODES_INTERNAL_BITS) + i);
> +				}
> +			}
> +		} else if (level == 0) {
> +			yaffs_ext_tags tags;
> +			__u32 obj_id = obj->obj_id;
> +
> +			chunk_offset <<=  YAFFS_TNODES_LEVEL0_BITS;
> +
> +			for (i = 0; i < YAFFS_NTNODES_LEVEL0; i++) {
> +				__u32 the_chunk = yaffs_get_group_base(dev, tn, i);
> +
> +				if (the_chunk > 0) {
> +					/* T(~0,(TSTR("verifying (%d:%d) %d"TENDSTR),tags.obj_id,tags.chunk_id,the_chunk)); */
> +					yaffs_rd_chunk_tags_nand(dev, the_chunk, NULL, &tags);
> +					if (tags.obj_id != obj_id || tags.chunk_id != chunk_offset) {
> +						T(~0, (TSTR("Object %d chunk_id %d NAND mismatch chunk %d tags (%d:%d)"TENDSTR),
> +							obj_id, chunk_offset, the_chunk,
> +							tags.obj_id, tags.chunk_id));
> +					}
> +				}
> +				chunk_offset++;
> +			}
> +		}
> +	}
> +
> +	return ok;

Here I think it would be nice to reduce the indentation level a bit by by 
doing something like:

int yaffs_verify_tnode_worker(yaffs_obj_t *obj, yaffs_tnode_t *tn,
                                     __u32 level, int chunk_offset)
{
     int i;
     yaffs_dev_t *dev = obj->my_dev;
     int ok = 1;
                     
     if (!tn)
          goto out; /* or simply  return ok;  */

     ... all the stuff currently inside the if() ...

 out:
     return ok;
}


-- 
Jesper Juhl <jj@chaosbits.net>             http://www.chaosbits.net/
Plain text mails only, please      http://www.expita.com/nomime.html
Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html

Re: [PATCH 24/29] Staging: yaffs2: yaffs_verify: Add files

[Pekka Enberg]

On Mon, Nov 1, 2010 at 9:16 PM, Jesper Juhl <jj@chaosbits.net> wrote:
> On Mon, 1 Nov 2010, Tracey Dent wrote:
>
>> Adding files to yaffs2 directory.
>>
>> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
>> ---
>>  drivers/staging/yaffs2/yaffs_verify.c |  631 +++++++++++++++++++++++++++++++++
>>  drivers/staging/yaffs2/yaffs_verify.h |   41 +++
>>  2 files changed, 672 insertions(+), 0 deletions(-)
>>  create mode 100644 drivers/staging/yaffs2/yaffs_verify.c
>>  create mode 100644 drivers/staging/yaffs2/yaffs_verify.h
>>
>> diff --git a/drivers/staging/yaffs2/yaffs_verify.c b/drivers/staging/yaffs2/yaffs_verify.c
>> new file mode 100644
>> index 0000000..89e730b
>> --- /dev/null
>> +++ b/drivers/staging/yaffs2/yaffs_verify.c
> ...
>> +#if 0
>
> Why are you trying to merge new code that's under '#if 0' (and not just
> here, but elsewhere as well)?
> Either it shouldn't be here, in which case it should just be omitted from
> the patch, or it needs to be here eventually in which case it should be
> fixed up so the '#if 0' can go away or simply just be added later when it
> has been fixed up.

You can do all sorts of crazy things under drivers/staging. So no, the
code doesn't need to be cleaned up prior to merging. You are, however,
correct on what needs to be done for this piece of code to be promoted
to mainline proper at some point in time.
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[PATCH 25/29] Staging: yaffs2: yaffs_vfs_glue.c: Add file

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_vfs_glue.c | 3019 +++++++++++++++++++++++++++++++
 1 files changed, 3019 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_vfs_glue.c

diff --git a/drivers/staging/yaffs2/yaffs_vfs_glue.c b/drivers/staging/yaffs2/yaffs_vfs_glue.c
new file mode 100644
index 0000000..b1b6840
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_vfs_glue.c
@@ -0,0 +1,3019 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ * Acknowledgements:
+ * Luc van OostenRyck for numerous patches.
+ * Nick Bane for numerous patches.
+ * Nick Bane for 2.5/2.6 integration.
+ * Andras Toth for mknod rdev issue.
+ * Michael Fischer for finding the problem with inode inconsistency.
+ * Some code bodily lifted from JFFS
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/*
+ *
+ * This is the file system front-end to YAFFS that hooks it up to
+ * the VFS.
+ *
+ * Special notes:
+ * >> 2.4: sb->u.generic_sbp points to the yaffs_dev_t associated with
+ *         this superblock
+ * >> 2.6: sb->s_fs_info  points to the yaffs_dev_t associated with this
+ *         superblock
+ * >> inode->u.generic_ip points to the associated yaffs_obj_t.
+ */
+
+/*
+ * NB There are two variants of Linux VFS glue code. This variant supports
+ * a single version and should not include any multi-version code.
+ */
+#include <linux/version.h>
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/proc_fs.h>
+#include <linux/smp_lock.h>
+#include <linux/pagemap.h>
+#include <linux/mtd/mtd.h>
+#include <linux/interrupt.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/namei.h>
+#include <linux/exportfs.h>
+#include <linux/kthread.h>
+#include <linux/delay.h>
+#include <linux/freezer.h>
+
+#include <asm/div64.h>
+
+
+#include <linux/statfs.h>
+
+#define UnlockPage(p) unlock_page(p)
+#define Page_Uptodate(page)	test_bit(PG_uptodate, &(page)->flags)
+
+#define yaffs_devname(sb, buf)	bdevname(sb->s_bdev, buf)
+
+#define YPROC_ROOT  NULL
+
+#define Y_INIT_TIMER(a)	init_timer_on_stack(a)
+
+#define WRITE_SIZE_STR "writesize"
+#define WRITE_SIZE(mtd) ((mtd)->writesize)
+
+
+static uint32_t YCALCBLOCKS(uint64_t partition_size, uint32_t block_size)
+{
+	uint64_t result = partition_size;
+	do_div(result, block_size);
+	return (uint32_t)result;
+}
+
+#include <linux/uaccess.h>
+#include <linux/mtd/mtd.h>
+
+#include "yportenv.h"
+#include "yaffs_trace.h"
+#include "yaffs_guts.h"
+
+#include "yaffs_linux.h"
+
+#include "yaffs_mtdif.h"
+#include "yaffs_mtdif1.h"
+#include "yaffs_mtdif2.h"
+
+unsigned int yaffs_trace_mask = YAFFS_TRACE_BAD_BLOCKS | YAFFS_TRACE_ALWAYS;
+unsigned int yaffs_wr_attempts = YAFFS_WR_ATTEMPTS;
+unsigned int yaffs_auto_checkpoint = 1;
+unsigned int yaffs_gc_control = 1;
+unsigned int yaffs_bg_enable = 1;
+
+/* Module Parameters */
+module_param(yaffs_trace_mask, uint, 0644);
+module_param(yaffs_wr_attempts, uint, 0644);
+module_param(yaffs_auto_checkpoint, uint, 0644);
+module_param(yaffs_gc_control, uint, 0644);
+module_param(yaffs_bg_enable, uint, 0644);
+
+#define Y_IGET(sb, inum) yaffs_iget((sb), (inum))
+
+static struct inode *yaffs_iget(struct super_block *sb, unsigned long ino);
+
+#define yaffs_inode_to_obj_lv(iptr) ((iptr)->i_private)
+#define yaffs_inode_to_obj(iptr) ((yaffs_obj_t *)(yaffs_inode_to_obj_lv(iptr)))
+#define yaffs_dentry_to_obj(dptr) yaffs_inode_to_obj((dptr)->d_inode)
+#define yaffs_super_to_dev(sb)	((yaffs_dev_t *)sb->s_fs_info)
+
+
+#define update_dir_time(dir) do {\
+			(dir)->i_ctime = (dir)->i_mtime = CURRENT_TIME; \
+		} while(0)
+		
+static void yaffs_put_super(struct super_block *sb);
+
+static ssize_t yaffs_file_write(struct file *f, const char *buf, size_t n,
+				loff_t *pos);
+static ssize_t yaffs_hold_space(struct file *f);
+static void yaffs_release_space(struct file *f);
+
+static int yaffs_file_flush(struct file *file, fl_owner_t id);
+
+static int yaffs_sync_object(struct file *file, int datasync);
+
+static int yaffs_readdir(struct file *f, void *dirent, filldir_t filldir);
+
+static int yaffs_create(struct inode *dir, struct dentry *dentry, int mode,
+			struct nameidata *n);
+static struct dentry *yaffs_lookup(struct inode *dir, struct dentry *dentry,
+					struct nameidata *n);
+static int yaffs_link(struct dentry *old_dentry, struct inode *dir,
+			struct dentry *dentry);
+static int yaffs_unlink(struct inode *dir, struct dentry *dentry);
+static int yaffs_symlink(struct inode *dir, struct dentry *dentry,
+			const char *symname);
+static int yaffs_mkdir(struct inode *dir, struct dentry *dentry, int mode);
+
+static int yaffs_mknod(struct inode *dir, struct dentry *dentry, int mode,
+			dev_t dev);
+static int yaffs_rename(struct inode *old_dir, struct dentry *old_dentry,
+			struct inode *new_dir, struct dentry *new_dentry);
+static int yaffs_setattr(struct dentry *dentry, struct iattr *attr);
+
+static int yaffs_sync_fs(struct super_block *sb, int wait);
+static void yaffs_write_super(struct super_block *sb);
+
+static int yaffs_statfs(struct dentry *dentry, struct kstatfs *buf);
+
+#ifdef YAFFS_HAS_PUT_INODE
+static void yaffs_put_inode(struct inode *inode);
+#endif
+
+static void yaffs_evict_inode(struct inode *);
+
+static int yaffs_readpage(struct file *file, struct page *page);
+static int yaffs_writepage(struct page *page, struct writeback_control *wbc);
+
+#ifdef CONFIG_YAFFS_XATTR
+int yaffs_setxattr(struct dentry *dentry, const char *name,
+			const void *value, size_t size, int flags);
+ssize_t yaffs_getxattr(struct dentry *dentry, const char *name, void *buff,
+			size_t size);
+int yaffs_removexattr(struct dentry *dentry, const char *name);
+ssize_t yaffs_listxattr(struct dentry *dentry, char *buff, size_t size);
+#endif
+
+
+static int yaffs_write_begin(struct file *filp, struct address_space *mapping,
+				loff_t pos, unsigned len, unsigned flags,
+				struct page **pagep, void **fsdata);
+static int yaffs_write_end(struct file *filp, struct address_space *mapping,
+				loff_t pos, unsigned len, unsigned copied,
+				struct page *pg, void *fsdadata);
+
+static int yaffs_readlink(struct dentry *dentry, char __user *buffer,
+				int buflen);
+void yaffs_put_link(struct dentry *dentry, struct nameidata *nd, void *alias);
+static void *yaffs_follow_link(struct dentry *dentry, struct nameidata *nd);
+
+static void yaffs_touch_super(yaffs_dev_t *dev);
+
+static loff_t yaffs_dir_llseek(struct file *file, loff_t offset, int origin);
+
+static int yaffs_vfs_setattr(struct inode *, struct iattr *);
+
+
+static struct address_space_operations yaffs_file_address_operations = {
+	.readpage = yaffs_readpage,
+	.writepage = yaffs_writepage,
+	.write_begin = yaffs_write_begin,
+	.write_end = yaffs_write_end,
+};
+
+
+static const struct file_operations yaffs_file_operations = {
+	.read = do_sync_read,
+	.write = do_sync_write,
+	.aio_read = generic_file_aio_read,
+	.aio_write = generic_file_aio_write,
+	.mmap = generic_file_mmap,
+	.flush = yaffs_file_flush,
+	.fsync = yaffs_sync_object,
+	.splice_read = generic_file_splice_read,
+	.splice_write = generic_file_splice_write,
+	.llseek = generic_file_llseek,
+};
+
+
+
+static const struct inode_operations yaffs_file_inode_operations = {
+	.setattr = yaffs_setattr,
+#ifdef CONFIG_YAFFS_XATTR
+	.setxattr = yaffs_setxattr,
+	.getxattr = yaffs_getxattr,
+	.listxattr = yaffs_listxattr,
+	.removexattr = yaffs_removexattr,
+#endif
+};
+
+static const struct inode_operations yaffs_symlink_inode_operations = {
+	.readlink = yaffs_readlink,
+	.follow_link = yaffs_follow_link,
+	.put_link = yaffs_put_link,
+	.setattr = yaffs_setattr,
+#ifdef CONFIG_YAFFS_XATTR
+	.setxattr = yaffs_setxattr,
+	.getxattr = yaffs_getxattr,
+	.listxattr = yaffs_listxattr,
+	.removexattr = yaffs_removexattr,
+#endif
+};
+
+static const struct inode_operations yaffs_dir_inode_operations = {
+	.create = yaffs_create,
+	.lookup = yaffs_lookup,
+	.link = yaffs_link,
+	.unlink = yaffs_unlink,
+	.symlink = yaffs_symlink,
+	.mkdir = yaffs_mkdir,
+	.rmdir = yaffs_unlink,
+	.mknod = yaffs_mknod,
+	.rename = yaffs_rename,
+	.setattr = yaffs_setattr,
+#ifdef CONFIG_YAFFS_XATTR
+	.setxattr = yaffs_setxattr,
+	.getxattr = yaffs_getxattr,
+	.listxattr = yaffs_listxattr,
+	.removexattr = yaffs_removexattr,
+#endif
+};
+
+static const struct file_operations yaffs_dir_operations = {
+	.read = generic_read_dir,
+	.readdir = yaffs_readdir,
+	.fsync = yaffs_sync_object,
+	.llseek = yaffs_dir_llseek,
+};
+
+static const struct super_operations yaffs_super_ops = {
+	.statfs = yaffs_statfs,
+#ifdef YAFFS_HAS_PUT_INODE
+	.put_inode = yaffs_put_inode,
+#endif
+	.put_super = yaffs_put_super,
+	.evict_inode = yaffs_evict_inode,
+	.sync_fs = yaffs_sync_fs,
+	.write_super = yaffs_write_super,
+};
+
+
+static  int yaffs_vfs_setattr(struct inode *inode, struct iattr *attr)
+{
+	setattr_copy(inode,attr);
+	return 0;
+}
+
+static  int yaffs_vfs_setsize(struct inode *inode, loff_t newsize)
+{
+	truncate_setsize(inode,newsize);
+	return 0;
+}
+
+static unsigned yaffs_gc_control_callback(yaffs_dev_t *dev)
+{
+	return yaffs_gc_control;
+}
+                	                                                                                          	
+static void yaffs_gross_lock(yaffs_dev_t *dev)
+{
+	T(YAFFS_TRACE_LOCK, (TSTR("yaffs locking %p\n"), current));
+	down(&(yaffs_dev_to_lc(dev)->gross_lock));
+	T(YAFFS_TRACE_LOCK, (TSTR("yaffs locked %p\n"), current));
+}
+
+static void yaffs_gross_unlock(yaffs_dev_t *dev)
+{
+	T(YAFFS_TRACE_LOCK, (TSTR("yaffs unlocking %p\n"), current));
+	up(&(yaffs_dev_to_lc(dev)->gross_lock));
+}
+
+
+
+/* ExportFS support */
+static struct inode *
+yaffs2_nfs_get_inode(struct super_block *sb, uint64_t ino, uint32_t generation)
+{
+	return Y_IGET(sb, ino);
+}
+
+static struct dentry *
+yaffs2_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len, int fh_type)
+{
+	return generic_fh_to_dentry(sb, fid, fh_len, fh_type, yaffs2_nfs_get_inode) ;
+}
+
+static struct dentry *
+ yaffs2_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len, int fh_type)
+{
+	return generic_fh_to_parent(sb, fid, fh_len, fh_type, yaffs2_nfs_get_inode);
+}
+
+struct dentry *yaffs2_get_parent(struct dentry *dentry)
+{
+
+	struct super_block *sb = dentry->d_inode->i_sb;
+	struct dentry *parent = ERR_PTR(-ENOENT);
+	struct inode *inode;
+	unsigned long parent_ino;
+	yaffs_obj_t *d_obj;
+	yaffs_obj_t *parent_obj;
+
+	d_obj = yaffs_inode_to_obj(dentry->d_inode);
+
+	if (d_obj) {
+		parent_obj = d_obj->parent;
+		if (parent_obj) {
+			parent_ino = yaffs_get_obj_inode(parent_obj);
+			inode = Y_IGET(sb, parent_ino);
+
+			if (IS_ERR(inode)) {
+				parent = ERR_CAST(inode);
+			} else {
+				parent = d_obtain_alias(inode);
+				if (!IS_ERR(parent)) {
+					parent = ERR_PTR(-ENOMEM);
+					iput(inode);
+				}
+			}
+		}
+	}
+
+	return parent;
+}
+
+/* Just declare a zero structure as a NULL value implies
+ * using the default functions of exportfs.
+ */
+
+static struct export_operations yaffs_export_ops =
+{
+	.fh_to_dentry = yaffs2_fh_to_dentry,
+	.fh_to_parent = yaffs2_fh_to_parent,
+	.get_parent = yaffs2_get_parent,
+} ;
+
+/*-----------------------------------------------------------------*/
+/* Directory search context allows us to unlock access to yaffs during
+ * filldir without causing problems with the directory being modified.
+ * This is similar to the tried and tested mechanism used in yaffs direct.
+ *
+ * A search context iterates along a doubly linked list of siblings in the
+ * directory. If the iterating object is deleted then this would corrupt
+ * the list iteration, likely causing a crash. The search context avoids
+ * this by using the remove_obj_fn to move the search context to the
+ * next object before the object is deleted.
+ *
+ * Many readdirs (and thus seach conexts) may be alive simulateously so
+ * each yaffs_dev_t has a list of these.
+ *
+ * A seach context lives for the duration of a readdir.
+ *
+ * All these functions must be called while yaffs is locked.
+ */
+
+struct yaffs_search_context {
+	yaffs_dev_t *dev;
+	yaffs_obj_t *dir_obj;
+	yaffs_obj_t *next_return;
+	struct ylist_head others;
+};
+
+/*
+ * yaffs_new_search() creates a new search context, initialises it and
+ * adds it to the device's search context list.
+ *
+ * Called at start of readdir.
+ */
+static struct yaffs_search_context * yaffs_new_search(yaffs_obj_t *dir)
+{
+	yaffs_dev_t *dev = dir->my_dev;
+	struct yaffs_search_context *sc = YMALLOC(sizeof(struct yaffs_search_context));
+	if(sc){
+		sc->dir_obj = dir;
+		sc->dev = dev;
+		if( ylist_empty(&sc->dir_obj->variant.dir_variant.children))
+			sc->next_return = NULL;
+		else
+			sc->next_return = ylist_entry(
+                                dir->variant.dir_variant.children.next,
+				yaffs_obj_t,siblings);
+		YINIT_LIST_HEAD(&sc->others);
+		ylist_add(&sc->others,&(yaffs_dev_to_lc(dev)->search_contexts));
+	}
+	return sc;
+}
+
+/*
+ * yaffs_search_end() disposes of a search context and cleans up.
+ */
+static void yaffs_search_end(struct yaffs_search_context * sc)
+{
+	if(sc){
+		ylist_del(&sc->others);
+		YFREE(sc);
+	}
+}
+
+/*
+ * yaffs_search_advance() moves a search context to the next object.
+ * Called when the search iterates or when an object removal causes
+ * the search context to be moved to the next object.
+ */
+static void yaffs_search_advance(struct yaffs_search_context *sc)
+{
+        if(!sc)
+                return;
+
+        if( sc->next_return == NULL ||
+                ylist_empty(&sc->dir_obj->variant.dir_variant.children))
+                sc->next_return = NULL;
+        else {
+                struct ylist_head *next = sc->next_return->siblings.next;
+
+                if( next == &sc->dir_obj->variant.dir_variant.children)
+                        sc->next_return = NULL; /* end of list */
+                else
+                        sc->next_return = ylist_entry(next,yaffs_obj_t,siblings);
+        }
+}
+
+/*
+ * yaffs_remove_obj_callback() is called when an object is unlinked.
+ * We check open search contexts and advance any which are currently
+ * on the object being iterated.
+ */
+static void yaffs_remove_obj_callback(yaffs_obj_t *obj)
+{
+
+        struct ylist_head *i;
+        struct yaffs_search_context *sc;
+        struct ylist_head *search_contexts = &(yaffs_dev_to_lc(obj->my_dev)->search_contexts);
+
+
+        /* Iterate through the directory search contexts.
+         * If any are currently on the object being removed, then advance
+         * the search context to the next object to prevent a hanging pointer.
+         */
+         ylist_for_each(i, search_contexts) {
+                if (i) {
+                        sc = ylist_entry(i, struct yaffs_search_context,others);
+                        if(sc->next_return == obj)
+                                yaffs_search_advance(sc);
+                }
+	}
+
+}
+
+
+/*-----------------------------------------------------------------*/
+
+static int yaffs_readlink(struct dentry *dentry, char __user *buffer,
+			int buflen)
+{
+	unsigned char *alias;
+	int ret;
+
+	yaffs_dev_t *dev = yaffs_dentry_to_obj(dentry)->my_dev;
+
+	yaffs_gross_lock(dev);
+
+	alias = yaffs_get_symlink_alias(yaffs_dentry_to_obj(dentry));
+
+	yaffs_gross_unlock(dev);
+
+	if (!alias)
+		return -ENOMEM;
+
+	ret = vfs_readlink(dentry, buffer, buflen, alias);
+	kfree(alias);
+	return ret;
+}
+
+static void *yaffs_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+	unsigned char *alias;
+	void *ret;
+	yaffs_dev_t *dev = yaffs_dentry_to_obj(dentry)->my_dev;
+
+	yaffs_gross_lock(dev);
+
+	alias = yaffs_get_symlink_alias(yaffs_dentry_to_obj(dentry));
+	yaffs_gross_unlock(dev);
+
+	if (!alias) {
+		ret = ERR_PTR(-ENOMEM);
+		goto out;
+	}
+
+	nd_set_link(nd, alias);
+	ret = (void *)alias;
+out:
+	return ret;
+}
+
+void yaffs_put_link(struct dentry *dentry, struct nameidata *nd, void *alias) {
+	kfree(alias);
+}
+
+struct inode *yaffs_get_inode(struct super_block *sb, int mode, int dev,
+				yaffs_obj_t *obj);
+
+/*
+ * Lookup is used to find objects in the fs
+ */
+
+static struct dentry *yaffs_lookup(struct inode *dir, struct dentry *dentry,
+				struct nameidata *n)
+{
+	yaffs_obj_t *obj;
+	struct inode *inode = NULL;	/* NCB 2.5/2.6 needs NULL here */
+
+	yaffs_dev_t *dev = yaffs_inode_to_obj(dir)->my_dev;
+
+	if(current != yaffs_dev_to_lc(dev)->readdir_process)
+		yaffs_gross_lock(dev);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_lookup for %d:%s\n"),
+		yaffs_inode_to_obj(dir)->obj_id, dentry->d_name.name));
+
+	obj = yaffs_find_by_name(yaffs_inode_to_obj(dir),
+					dentry->d_name.name);
+
+	obj = yaffs_get_equivalent_obj(obj);	/* in case it was a hardlink */
+
+	/* Can't hold gross lock when calling yaffs_get_inode() */
+	if(current != yaffs_dev_to_lc(dev)->readdir_process)
+		yaffs_gross_unlock(dev);
+
+	if (obj) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_lookup found %d\n"), obj->obj_id));
+
+		inode = yaffs_get_inode(dir->i_sb, obj->yst_mode, 0, obj);
+
+		if (inode) {
+			T(YAFFS_TRACE_OS,
+				(TSTR("yaffs_loookup dentry \n")));
+/* #if 0 asserted by NCB for 2.5/6 compatability - falls through to
+ * d_add even if NULL inode */
+#if 0
+			/*dget(dentry); // try to solve directory bug */
+			d_add(dentry, inode);
+
+			/* return dentry; */
+			return NULL;
+#endif
+		}
+
+	} else {
+		T(YAFFS_TRACE_OS,(TSTR("yaffs_lookup not found\n")));
+
+	}
+
+/* added NCB for 2.5/6 compatability - forces add even if inode is
+ * NULL which creates dentry hash */
+	d_add(dentry, inode);
+
+	return NULL;
+}
+
+
+#ifdef YAFFS_HAS_PUT_INODE
+
+/* For now put inode is just for debugging
+ * Put inode is called when the inode **structure** is put.
+ */
+static void yaffs_put_inode(struct inode *inode)
+{
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_put_inode: ino %d, count %d\n"), (int)inode->i_ino,
+		atomic_read(&inode->i_count)));
+
+}
+#endif
+
+
+static void yaffs_unstitch_obj(struct inode *inode, yaffs_obj_t *obj)
+{
+	/* Clear the association between the inode and
+	 * the yaffs_obj_t.
+	 */
+	obj->my_inode = NULL;
+	yaffs_inode_to_obj_lv(inode) = NULL;
+
+	/* If the object freeing was deferred, then the real
+	 * free happens now.
+	 * This should fix the inode inconsistency problem.
+	 */
+	yaffs_handle_defered_free(obj);
+}
+
+/* yaffs_evict_inode combines into one operation what was previously done in
+ * yaffs_clear_inode() and yaffs_delete_inode()
+ *
+ */
+static void yaffs_evict_inode( struct inode *inode)
+{
+	yaffs_obj_t *obj;
+	yaffs_dev_t *dev;
+	int deleteme = 0;
+
+	obj = yaffs_inode_to_obj(inode);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_evict_inode: ino %d, count %d %s\n"), (int)inode->i_ino,
+		atomic_read(&inode->i_count),
+		obj ? "object exists" : "null object"));
+
+	if (!inode->i_nlink && !is_bad_inode(inode))
+		deleteme = 1;
+	truncate_inode_pages(&inode->i_data,0);
+	end_writeback(inode);
+
+	if(deleteme && obj){
+		dev = obj->my_dev;
+		yaffs_gross_lock(dev);
+		yaffs_del_obj(obj);
+		yaffs_gross_unlock(dev);
+	}
+	if (obj) {
+		dev = obj->my_dev;
+		yaffs_gross_lock(dev);
+		yaffs_unstitch_obj(inode,obj);
+		yaffs_gross_unlock(dev);
+	}
+
+
+}
+
+
+static int yaffs_file_flush(struct file *file, fl_owner_t id)
+{
+	yaffs_obj_t *obj = yaffs_dentry_to_obj(file->f_dentry);
+
+	yaffs_dev_t *dev = obj->my_dev;
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_file_flush object %d (%s)\n"), obj->obj_id,
+		obj->dirty ? "dirty" : "clean"));
+
+	yaffs_gross_lock(dev);
+
+	yaffs_flush_file(obj, 1, 0);
+
+	yaffs_gross_unlock(dev);
+
+	return 0;
+}
+
+static int yaffs_readpage_nolock(struct file *f, struct page *pg)
+{
+	/* Lifted from jffs2 */
+
+	yaffs_obj_t *obj;
+	unsigned char *pg_buf;
+	int ret;
+
+	yaffs_dev_t *dev;
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_readpage_nolock at %08x, size %08x\n"),
+		(unsigned)(pg->index << PAGE_CACHE_SHIFT),
+		(unsigned)PAGE_CACHE_SIZE));
+
+	obj = yaffs_dentry_to_obj(f->f_dentry);
+
+	dev = obj->my_dev;
+
+	BUG_ON(!PageLocked(pg));
+
+	pg_buf = kmap(pg);
+	/* FIXME: Can kmap fail? */
+
+	yaffs_gross_lock(dev);
+
+	ret = yaffs_file_rd(obj, pg_buf,
+				pg->index << PAGE_CACHE_SHIFT,
+				PAGE_CACHE_SIZE);
+
+	yaffs_gross_unlock(dev);
+
+	if (ret >= 0)
+		ret = 0;
+
+	if (ret) {
+		ClearPageUptodate(pg);
+		SetPageError(pg);
+	} else {
+		SetPageUptodate(pg);
+		ClearPageError(pg);
+	}
+
+	flush_dcache_page(pg);
+	kunmap(pg);
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_readpage_nolock done\n")));
+	return ret;
+}
+
+static int yaffs_readpage_unlock(struct file *f, struct page *pg)
+{
+	int ret = yaffs_readpage_nolock(f, pg);
+	UnlockPage(pg);
+	return ret;
+}
+
+static int yaffs_readpage(struct file *f, struct page *pg)
+{
+	int ret;
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_readpage\n")));
+	ret=yaffs_readpage_unlock(f, pg);
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_readpage done\n")));
+	return ret;
+}
+
+/* writepage inspired by/stolen from smbfs */
+
+static int yaffs_writepage(struct page *page, struct writeback_control *wbc)
+{
+	yaffs_dev_t *dev;
+	struct address_space *mapping = page->mapping;
+	struct inode *inode;
+	unsigned long end_index;
+	char *buffer;
+	yaffs_obj_t *obj;
+	int n_written = 0;
+	unsigned n_bytes;
+	loff_t i_size;
+
+	if (!mapping)
+		BUG();
+	inode = mapping->host;
+	if (!inode)
+		BUG();
+	i_size = i_size_read(inode);
+
+	end_index = i_size >> PAGE_CACHE_SHIFT;
+
+	if(page->index < end_index)
+		n_bytes = PAGE_CACHE_SIZE;
+	else {
+		n_bytes = i_size & (PAGE_CACHE_SIZE -1);
+
+		if (page->index > end_index || !n_bytes) {
+			T(YAFFS_TRACE_OS,
+				(TSTR("yaffs_writepage at %08x, inode size = %08x!!!\n"),
+				(unsigned)(page->index << PAGE_CACHE_SHIFT),
+				(unsigned)inode->i_size));
+			T(YAFFS_TRACE_OS,
+				(TSTR("                -> don't care!!\n")));
+
+			zero_user_segment(page,0,PAGE_CACHE_SIZE);
+			set_page_writeback(page);
+			unlock_page(page);
+			end_page_writeback(page);
+			return 0;
+		}
+	}
+
+	if(n_bytes != PAGE_CACHE_SIZE)
+		zero_user_segment(page,n_bytes,PAGE_CACHE_SIZE);
+
+	get_page(page);
+
+	buffer = kmap(page);
+
+	obj = yaffs_inode_to_obj(inode);
+	dev = obj->my_dev;
+	yaffs_gross_lock(dev);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_writepage at %08x, size %08x\n"),
+		(unsigned)(page->index << PAGE_CACHE_SHIFT), n_bytes));
+	T(YAFFS_TRACE_OS,
+		(TSTR("writepag0: obj = %05x, ino = %05x\n"),
+		(int)obj->variant.file_variant.file_size, (int)inode->i_size));
+
+	n_written = yaffs_wr_file(obj, buffer,
+			page->index << PAGE_CACHE_SHIFT, n_bytes, 0);
+
+	yaffs_touch_super(dev);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("writepag1: obj = %05x, ino = %05x\n"),
+		(int)obj->variant.file_variant.file_size, (int)inode->i_size));
+
+	yaffs_gross_unlock(dev);
+
+	kunmap(page);
+	set_page_writeback(page);
+	unlock_page(page);
+	end_page_writeback(page);
+	put_page(page);
+
+	return (n_written == n_bytes) ? 0 : -ENOSPC;
+}
+
+
+static int yaffs_write_begin(struct file *filp, struct address_space *mapping,
+				loff_t pos, unsigned len, unsigned flags,
+				struct page **pagep, void **fsdata)
+{
+	struct page *pg = NULL;
+	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+
+	int ret = 0;
+	int space_held = 0;
+
+	/* Get a page */
+	pg = grab_cache_page_write_begin(mapping, index, flags);
+
+	*pagep = pg;
+	if (!pg) {
+		ret =  -ENOMEM;
+		goto out;
+	}
+	T(YAFFS_TRACE_OS,
+		(TSTR("start yaffs_write_begin index %d(%x) uptodate %d\n"),
+		(int)index,(int)index,Page_Uptodate(pg) ? 1 : 0));
+
+	/* Get fs space */
+	space_held = yaffs_hold_space(filp);
+
+	if (!space_held) {
+		ret = -ENOSPC;
+		goto out;
+	}
+
+	/* Update page if required */
+
+	if (!Page_Uptodate(pg))
+		ret = yaffs_readpage_nolock(filp, pg);
+
+	if (ret)
+		goto out;
+
+	/* Happy path return */
+	T(YAFFS_TRACE_OS, (TSTR("end yaffs_write_begin - ok\n")));
+
+	return 0;
+
+out:
+	T(YAFFS_TRACE_OS,
+		(TSTR("end yaffs_write_begin fail returning %d\n"), ret));
+	if (space_held)
+		yaffs_release_space(filp);
+	if (pg) {
+		unlock_page(pg);
+		page_cache_release(pg);
+	}
+	return ret;
+}
+
+
+static int yaffs_write_end(struct file *filp, struct address_space *mapping,
+				loff_t pos, unsigned len, unsigned copied,
+				struct page *pg, void *fsdadata)
+{
+	int ret = 0;
+	void *addr, *kva;
+	uint32_t offset_into_page = pos & (PAGE_CACHE_SIZE - 1);
+
+	kva = kmap(pg);
+	addr = kva + offset_into_page;
+
+	T(YAFFS_TRACE_OS,
+		("yaffs_write_end addr %p pos %x n_bytes %d\n",
+		addr,(unsigned)pos, copied));
+
+	ret = yaffs_file_write(filp, addr, copied, &pos);
+
+	if (ret != copied) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_write_end not same size ret %d  copied %d\n"),
+			ret, copied));
+		SetPageError(pg);
+	} else {
+		/* Nothing */
+	}
+
+	kunmap(pg);
+
+	yaffs_release_space(filp);
+	unlock_page(pg);
+	page_cache_release(pg);
+	return ret;
+}
+
+
+static void yaffs_fill_inode_from_obj(struct inode *inode, yaffs_obj_t *obj)
+{
+	if (inode && obj) {
+
+
+		/* Check mode against the variant type and attempt to repair if broken. */
+		__u32 mode = obj->yst_mode;
+		switch (obj->variant_type) {
+		case YAFFS_OBJECT_TYPE_FILE:
+			if (!S_ISREG(mode)) {
+				obj->yst_mode &= ~S_IFMT;
+				obj->yst_mode |= S_IFREG;
+			}
+
+			break;
+		case YAFFS_OBJECT_TYPE_SYMLINK:
+			if (!S_ISLNK(mode)) {
+				obj->yst_mode &= ~S_IFMT;
+				obj->yst_mode |= S_IFLNK;
+			}
+
+			break;
+		case YAFFS_OBJECT_TYPE_DIRECTORY:
+			if (!S_ISDIR(mode)) {
+				obj->yst_mode &= ~S_IFMT;
+				obj->yst_mode |= S_IFDIR;
+			}
+
+			break;
+		case YAFFS_OBJECT_TYPE_UNKNOWN:
+		case YAFFS_OBJECT_TYPE_HARDLINK:
+		case YAFFS_OBJECT_TYPE_SPECIAL:
+		default:
+			/* TODO? */
+			break;
+		}
+
+		inode->i_flags |= S_NOATIME;
+
+		inode->i_ino = obj->obj_id;
+		inode->i_mode = obj->yst_mode;
+		inode->i_uid = obj->yst_uid;
+		inode->i_gid = obj->yst_gid;
+
+		inode->i_rdev = old_decode_dev(obj->yst_rdev);
+
+		inode->i_atime.tv_sec = (time_t) (obj->yst_atime);
+		inode->i_atime.tv_nsec = 0;
+		inode->i_mtime.tv_sec = (time_t) obj->yst_mtime;
+		inode->i_mtime.tv_nsec = 0;
+		inode->i_ctime.tv_sec = (time_t) obj->yst_ctime;
+		inode->i_ctime.tv_nsec = 0;
+		inode->i_size = yaffs_get_obj_length(obj);
+		inode->i_blocks = (inode->i_size + 511) >> 9;
+
+		inode->i_nlink = yaffs_get_obj_link_count(obj);
+
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_fill_inode mode %x uid %d gid %d size %d count %d\n"),
+			inode->i_mode, inode->i_uid, inode->i_gid,
+			(int)inode->i_size, atomic_read(&inode->i_count)));
+
+		switch (obj->yst_mode & S_IFMT) {
+		default:	/* fifo, device or socket */
+			init_special_inode(inode, obj->yst_mode,
+					old_decode_dev(obj->yst_rdev));
+			break;
+		case S_IFREG:	/* file */
+			inode->i_op = &yaffs_file_inode_operations;
+			inode->i_fop = &yaffs_file_operations;
+			inode->i_mapping->a_ops =
+				&yaffs_file_address_operations;
+			break;
+		case S_IFDIR:	/* directory */
+			inode->i_op = &yaffs_dir_inode_operations;
+			inode->i_fop = &yaffs_dir_operations;
+			break;
+		case S_IFLNK:	/* symlink */
+			inode->i_op = &yaffs_symlink_inode_operations;
+			break;
+		}
+
+		yaffs_inode_to_obj_lv(inode) = obj;
+
+		obj->my_inode = inode;
+
+	} else {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_fill_inode invalid parameters\n")));
+	}
+
+}
+
+struct inode *yaffs_get_inode(struct super_block *sb, int mode, int dev,
+				yaffs_obj_t *obj)
+{
+	struct inode *inode;
+
+	if (!sb) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_get_inode for NULL super_block!!\n")));
+		return NULL;
+
+	}
+
+	if (!obj) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_get_inode for NULL object!!\n")));
+		return NULL;
+
+	}
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_get_inode for object %d\n"), obj->obj_id));
+
+	inode = Y_IGET(sb, obj->obj_id);
+	if (IS_ERR(inode))
+		return NULL;
+
+	/* NB Side effect: iget calls back to yaffs_read_inode(). */
+	/* iget also increments the inode's i_count */
+	/* NB You can't be holding gross_lock or deadlock will happen! */
+
+	return inode;
+}
+
+static ssize_t yaffs_file_write(struct file *f, const char *buf, size_t n,
+				loff_t *pos)
+{
+	yaffs_obj_t *obj;
+	int n_written, ipos;
+	struct inode *inode;
+	yaffs_dev_t *dev;
+
+	obj = yaffs_dentry_to_obj(f->f_dentry);
+
+	dev = obj->my_dev;
+
+	yaffs_gross_lock(dev);
+
+	inode = f->f_dentry->d_inode;
+
+	if (!S_ISBLK(inode->i_mode) && f->f_flags & O_APPEND)
+		ipos = inode->i_size;
+	else
+		ipos = *pos;
+
+	if (!obj)
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_file_write: hey obj is null!\n")));
+	else
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_file_write about to write writing %u(%x) bytes"
+			"to object %d at %d(%x)\n"),
+			(unsigned) n, (unsigned) n, obj->obj_id, ipos,ipos));
+
+	n_written = yaffs_wr_file(obj, buf, ipos, n, 0);
+
+	yaffs_touch_super(dev);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_file_write: %d(%x) bytes written\n"),
+		(unsigned )n,(unsigned)n));
+
+	if (n_written > 0) {
+		ipos += n_written;
+		*pos = ipos;
+		if (ipos > inode->i_size) {
+			inode->i_size = ipos;
+			inode->i_blocks = (ipos + 511) >> 9;
+
+			T(YAFFS_TRACE_OS,
+				(TSTR("yaffs_file_write size updated to %d bytes, "
+				"%d blocks\n"),
+				ipos, (int)(inode->i_blocks)));
+		}
+
+	}
+	yaffs_gross_unlock(dev);
+	return (n_written == 0) && (n > 0) ? -ENOSPC : n_written;
+}
+
+/* Space holding and freeing is done to ensure we have space available for write_begin/end */
+/* For now we just assume few parallel writes and check against a small number. */
+/* Todo: need to do this with a counter to handle parallel reads better */
+
+static ssize_t yaffs_hold_space(struct file *f)
+{
+	yaffs_obj_t *obj;
+	yaffs_dev_t *dev;
+
+	int n_free_chunks;
+
+
+	obj = yaffs_dentry_to_obj(f->f_dentry);
+
+	dev = obj->my_dev;
+
+	yaffs_gross_lock(dev);
+
+	n_free_chunks = yaffs_get_n_free_chunks(dev);
+
+	yaffs_gross_unlock(dev);
+
+	return (n_free_chunks > 20) ? 1 : 0;
+}
+
+static void yaffs_release_space(struct file *f)
+{
+	yaffs_obj_t *obj;
+	yaffs_dev_t *dev;
+
+
+	obj = yaffs_dentry_to_obj(f->f_dentry);
+
+	dev = obj->my_dev;
+
+	yaffs_gross_lock(dev);
+
+
+	yaffs_gross_unlock(dev);
+}
+
+
+static loff_t yaffs_dir_llseek(struct file *file, loff_t offset, int origin)
+{
+	long long retval;
+
+	lock_kernel();
+
+	switch (origin){
+	case 2:
+		offset += i_size_read(file->f_path.dentry->d_inode);
+		break;
+	case 1:
+		offset += file->f_pos;
+	}
+	retval = -EINVAL;
+
+	if (offset >= 0){
+		if (offset != file->f_pos)
+			file->f_pos = offset;
+
+		retval = offset;
+	}
+	unlock_kernel();
+	return retval;
+}
+
+
+static int yaffs_readdir(struct file *f, void *dirent, filldir_t filldir)
+{
+	yaffs_obj_t *obj;
+	yaffs_dev_t *dev;
+        struct yaffs_search_context *sc;
+	struct inode *inode = f->f_dentry->d_inode;
+	unsigned long offset, curoffs;
+	yaffs_obj_t *l;
+        int ret_val = 0;
+
+	char name[YAFFS_MAX_NAME_LENGTH + 1];
+
+	obj = yaffs_dentry_to_obj(f->f_dentry);
+	dev = obj->my_dev;
+
+	yaffs_gross_lock(dev);
+
+	yaffs_dev_to_lc(dev)->readdir_process = current;
+
+	offset = f->f_pos;
+
+        sc = yaffs_new_search(obj);
+        if(!sc){
+                ret_val = -ENOMEM;
+                goto out;
+        }
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_readdir: starting at %d\n"), (int)offset));
+
+	if (offset == 0) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_readdir: entry . ino %d \n"),
+			(int)inode->i_ino));
+		yaffs_gross_unlock(dev);
+		if (filldir(dirent, ".", 1, offset, inode->i_ino, DT_DIR) < 0){
+			yaffs_gross_lock(dev);
+			goto out;
+		}
+		yaffs_gross_lock(dev);
+		offset++;
+		f->f_pos++;
+	}
+	if (offset == 1) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_readdir: entry .. ino %d \n"),
+			(int)f->f_dentry->d_parent->d_inode->i_ino));
+		yaffs_gross_unlock(dev);
+		if (filldir(dirent, "..", 2, offset,
+			f->f_dentry->d_parent->d_inode->i_ino, DT_DIR) < 0){
+			yaffs_gross_lock(dev);
+			goto out;
+		}
+		yaffs_gross_lock(dev);
+		offset++;
+		f->f_pos++;
+	}
+
+	curoffs = 1;
+
+	/* If the directory has changed since the open or last call to
+	   readdir, rewind to after the 2 canned entries. */
+	if (f->f_version != inode->i_version) {
+		offset = 2;
+		f->f_pos = offset;
+		f->f_version = inode->i_version;
+	}
+
+	while(sc->next_return){
+		curoffs++;
+                l = sc->next_return;
+		if (curoffs >= offset) {
+                        int this_inode = yaffs_get_obj_inode(l);
+                        int this_type = yaffs_get_obj_type(l);
+
+			yaffs_get_obj_name(l, name,
+					    YAFFS_MAX_NAME_LENGTH + 1);
+			T(YAFFS_TRACE_OS,
+			  (TSTR("yaffs_readdir: %s inode %d\n"),
+			  name, yaffs_get_obj_inode(l)));
+
+                        yaffs_gross_unlock(dev);
+
+			if (filldir(dirent,
+					name,
+					strlen(name),
+					offset,
+					this_inode,
+					this_type) < 0){
+				yaffs_gross_lock(dev);
+				goto out;
+			}
+
+                        yaffs_gross_lock(dev);
+
+			offset++;
+			f->f_pos++;
+		}
+                yaffs_search_advance(sc);
+	}
+
+out:
+	yaffs_search_end(sc);
+	yaffs_dev_to_lc(dev)->readdir_process = NULL;
+	yaffs_gross_unlock(dev);
+
+	return ret_val;
+}
+
+
+
+/*
+ * File creation. Allocate an inode, and we're done..
+ */
+
+#define YCRED(x) (x->cred)
+
+static int yaffs_mknod(struct inode *dir, struct dentry *dentry, int mode,
+			dev_t rdev)
+{
+	struct inode *inode;
+
+	yaffs_obj_t *obj = NULL;
+	yaffs_dev_t *dev;
+
+	yaffs_obj_t *parent = yaffs_inode_to_obj(dir);
+
+	int error = -ENOSPC;
+	uid_t uid = YCRED(current)->fsuid;
+	gid_t gid = (dir->i_mode & S_ISGID) ? dir->i_gid : YCRED(current)->fsgid;
+
+	if ((dir->i_mode & S_ISGID) && S_ISDIR(mode))
+		mode |= S_ISGID;
+
+	if (parent) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_mknod: parent object %d type %d\n"),
+			parent->obj_id, parent->variant_type));
+	} else {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_mknod: could not get parent object\n")));
+		return -EPERM;
+	}
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_mknod: making oject for %s, "
+			"mode %x dev %x\n"),
+			dentry->d_name.name, mode, rdev));
+
+	dev = parent->my_dev;
+
+	yaffs_gross_lock(dev);
+
+	switch (mode & S_IFMT) {
+	default:
+		/* Special (socket, fifo, device...) */
+		T(YAFFS_TRACE_OS, (TSTR("yaffs_mknod: making special\n")));
+		obj = yaffs_create_special(parent, dentry->d_name.name, mode, uid,
+				gid, old_encode_dev(rdev));
+		break;
+	case S_IFREG:		/* file          */
+		T(YAFFS_TRACE_OS, (TSTR("yaffs_mknod: making file\n")));
+		obj = yaffs_create_file(parent, dentry->d_name.name, mode, uid,
+				gid);
+		break;
+	case S_IFDIR:		/* directory */
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_mknod: making directory\n")));
+		obj = yaffs_create_dir(parent, dentry->d_name.name, mode,
+					uid, gid);
+		break;
+	case S_IFLNK:		/* symlink */
+		T(YAFFS_TRACE_OS, (TSTR("yaffs_mknod: making symlink\n")));
+		obj = NULL;	/* Do we ever get here? */
+		break;
+	}
+
+	/* Can not call yaffs_get_inode() with gross lock held */
+	yaffs_gross_unlock(dev);
+
+	if (obj) {
+		inode = yaffs_get_inode(dir->i_sb, mode, rdev, obj);
+		d_instantiate(dentry, inode);
+		update_dir_time(dir);
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_mknod created object %d count = %d\n"),
+			obj->obj_id, atomic_read(&inode->i_count)));
+		error = 0;
+		yaffs_fill_inode_from_obj(dir,parent);
+	} else {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_mknod failed making object\n")));
+		error = -ENOMEM;
+	}
+
+	return error;
+}
+
+static int yaffs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+{
+	int ret_val;
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_mkdir\n")));
+	ret_val = yaffs_mknod(dir, dentry, mode | S_IFDIR, 0);
+	return ret_val;
+}
+
+static int yaffs_create(struct inode *dir, struct dentry *dentry, int mode,
+			struct nameidata *n)
+{
+	T(YAFFS_TRACE_OS,(TSTR("yaffs_create\n")));
+	return yaffs_mknod(dir, dentry, mode | S_IFREG, 0);
+}
+
+static int yaffs_unlink(struct inode *dir, struct dentry *dentry)
+{
+	int ret_val;
+
+	yaffs_dev_t *dev;
+	yaffs_obj_t *obj;
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_unlink %d:%s\n"),
+		(int)(dir->i_ino),
+		dentry->d_name.name));
+	obj = yaffs_inode_to_obj(dir);
+	dev = obj->my_dev;
+
+	yaffs_gross_lock(dev);
+
+	ret_val = yaffs_unlinker(obj, dentry->d_name.name);
+
+	if (ret_val == YAFFS_OK) {
+		dentry->d_inode->i_nlink--;
+		dir->i_version++;
+		yaffs_gross_unlock(dev);
+		mark_inode_dirty(dentry->d_inode);
+		update_dir_time(dir);
+		return 0;
+	}
+	yaffs_gross_unlock(dev);
+	return -ENOTEMPTY;
+}
+
+/*
+ * Create a link...
+ */
+static int yaffs_link(struct dentry *old_dentry, struct inode *dir,
+			struct dentry *dentry)
+{
+	struct inode *inode = old_dentry->d_inode;
+	yaffs_obj_t *obj = NULL;
+	yaffs_obj_t *link = NULL;
+	yaffs_dev_t *dev;
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_link\n")));
+
+	obj = yaffs_inode_to_obj(inode);
+	dev = obj->my_dev;
+
+	yaffs_gross_lock(dev);
+
+	if (!S_ISDIR(inode->i_mode))		/* Don't link directories */
+		link = yaffs_link_obj(yaffs_inode_to_obj(dir), dentry->d_name.name,
+			obj);
+
+	if (link) {
+		old_dentry->d_inode->i_nlink = yaffs_get_obj_link_count(obj);
+		d_instantiate(dentry, old_dentry->d_inode);
+		atomic_inc(&old_dentry->d_inode->i_count);
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_link link count %d i_count %d\n"),
+			old_dentry->d_inode->i_nlink,
+			atomic_read(&old_dentry->d_inode->i_count)));
+	}
+
+	yaffs_gross_unlock(dev);
+
+	if (link){
+		update_dir_time(dir);
+		return 0;
+	}
+
+	return -EPERM;
+}
+
+static int yaffs_symlink(struct inode *dir, struct dentry *dentry,
+				const char *symname)
+{
+	yaffs_obj_t *obj;
+	yaffs_dev_t *dev;
+	uid_t uid = YCRED(current)->fsuid;
+	gid_t gid = (dir->i_mode & S_ISGID) ? dir->i_gid : YCRED(current)->fsgid;
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_symlink\n")));
+
+	dev = yaffs_inode_to_obj(dir)->my_dev;
+	yaffs_gross_lock(dev);
+	obj = yaffs_create_symlink(yaffs_inode_to_obj(dir), dentry->d_name.name,
+				S_IFLNK | S_IRWXUGO, uid, gid, symname);
+	yaffs_gross_unlock(dev);
+
+	if (obj) {
+		struct inode *inode;
+
+		inode = yaffs_get_inode(dir->i_sb, obj->yst_mode, 0, obj);
+		d_instantiate(dentry, inode);
+		update_dir_time(dir);
+		T(YAFFS_TRACE_OS, (TSTR("symlink created OK\n")));
+		return 0;
+	} else {
+		T(YAFFS_TRACE_OS, (TSTR("symlink not created\n")));
+	}
+
+	return -ENOMEM;
+}
+
+static int yaffs_sync_object(struct file *file, int datasync)
+{
+
+	yaffs_obj_t *obj;
+	yaffs_dev_t *dev;
+	struct dentry *dentry = file->f_path.dentry;
+
+	obj = yaffs_dentry_to_obj(dentry);
+
+	dev = obj->my_dev;
+
+	T(YAFFS_TRACE_OS | YAFFS_TRACE_SYNC,
+		(TSTR("yaffs_sync_object\n")));
+	yaffs_gross_lock(dev);
+	yaffs_flush_file(obj, 1, datasync);
+	yaffs_gross_unlock(dev);
+	return 0;
+}
+
+/*
+ * The VFS layer already does all the dentry stuff for rename.
+ *
+ * NB: POSIX says you can rename an object over an old object of the same name
+ */
+static int yaffs_rename(struct inode *old_dir, struct dentry *old_dentry,
+			struct inode *new_dir, struct dentry *new_dentry)
+{
+	yaffs_dev_t *dev;
+	int ret_val = YAFFS_FAIL;
+	yaffs_obj_t *target;
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_rename\n")));
+	dev = yaffs_inode_to_obj(old_dir)->my_dev;
+
+	yaffs_gross_lock(dev);
+
+	/* Check if the target is an existing directory that is not empty. */
+	target = yaffs_find_by_name(yaffs_inode_to_obj(new_dir),
+				new_dentry->d_name.name);
+
+
+
+	if (target && target->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY &&
+		!ylist_empty(&target->variant.dir_variant.children)) {
+
+		T(YAFFS_TRACE_OS, (TSTR("target is non-empty dir\n")));
+
+		ret_val = YAFFS_FAIL;
+	} else {
+		/* Now does unlinking internally using shadowing mechanism */
+		T(YAFFS_TRACE_OS, (TSTR("calling yaffs_rename_obj\n")));
+
+		ret_val = yaffs_rename_obj(yaffs_inode_to_obj(old_dir),
+				old_dentry->d_name.name,
+				yaffs_inode_to_obj(new_dir),
+				new_dentry->d_name.name);
+	}
+	yaffs_gross_unlock(dev);
+
+	if (ret_val == YAFFS_OK) {
+		if (target) {
+			new_dentry->d_inode->i_nlink--;
+			mark_inode_dirty(new_dentry->d_inode);
+		}
+		
+		update_dir_time(old_dir);
+		if(old_dir != new_dir)
+			update_dir_time(new_dir);
+		return 0;
+	} else {
+		return -ENOTEMPTY;
+	}
+}
+
+static int yaffs_setattr(struct dentry *dentry, struct iattr *attr)
+{
+	struct inode *inode = dentry->d_inode;
+	int error = 0;
+	yaffs_dev_t *dev;
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_setattr of object %d\n"),
+		yaffs_inode_to_obj(inode)->obj_id));
+
+	/* Fail if a requested resize >= 2GB */		
+	if (attr->ia_valid & ATTR_SIZE &&
+		(attr->ia_size >> 31))
+		error = -EINVAL;
+
+	if (error == 0)
+		error = inode_change_ok(inode, attr);
+	if (error == 0) {
+		int result;
+		if (!error){
+			error = yaffs_vfs_setattr(inode, attr);
+			T(YAFFS_TRACE_OS,(TSTR("inode_setattr called\n")));
+			if (attr->ia_valid & ATTR_SIZE){
+                        	yaffs_vfs_setsize(inode,attr->ia_size);
+                        	inode->i_blocks = (inode->i_size + 511) >> 9;
+			}
+		}
+		dev = yaffs_inode_to_obj(inode)->my_dev;
+		if (attr->ia_valid & ATTR_SIZE){
+			T(YAFFS_TRACE_OS,(TSTR("resize to %d(%x)\n"),
+				(int)(attr->ia_size),(int)(attr->ia_size)));
+		}
+		yaffs_gross_lock(dev);
+		result = yaffs_set_attribs(yaffs_inode_to_obj(inode), attr);
+		if(result == YAFFS_OK) {
+			error = 0;
+		} else {
+			error = -EPERM;
+		}
+		yaffs_gross_unlock(dev);
+
+	}
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_setattr done returning %d\n"),error));
+
+	return error;
+}
+
+#ifdef CONFIG_YAFFS_XATTR
+int yaffs_setxattr(struct dentry *dentry, const char *name,
+			const void *value, size_t size, int flags)
+{
+	struct inode *inode = dentry->d_inode;
+	int error = 0;
+	yaffs_dev_t *dev;
+	yaffs_obj_t *obj = yaffs_inode_to_obj(inode);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_setxattr of object %d\n"),
+		obj->obj_id));
+
+
+	if (error == 0) {
+		int result;
+		dev = obj->my_dev;
+		yaffs_gross_lock(dev);
+		result = yaffs_set_xattrib(obj, name, value, size, flags);
+		if(result == YAFFS_OK)
+			error = 0;
+		else if(result < 0)
+			error = result;
+		yaffs_gross_unlock(dev);
+
+	}
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_setxattr done returning %d\n"),error));
+
+	return error;
+}
+
+
+ssize_t yaffs_getxattr(struct dentry *dentry, const char *name, void *buff,
+			size_t size)
+{
+	struct inode *inode = dentry->d_inode;
+	int error = 0;
+	yaffs_dev_t *dev;
+	yaffs_obj_t *obj = yaffs_inode_to_obj(inode);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_getxattr \"%s\" from object %d\n"),
+		name, obj->obj_id));
+
+	if (error == 0) {
+		dev = obj->my_dev;
+		yaffs_gross_lock(dev);
+		error = yaffs_get_xattrib(obj, name, buff, size);
+		yaffs_gross_unlock(dev);
+
+	}
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_getxattr done returning %d\n"),error));
+
+	return error;
+}
+
+int yaffs_removexattr(struct dentry *dentry, const char *name)
+{
+	struct inode *inode = dentry->d_inode;
+	int error = 0;
+	yaffs_dev_t *dev;
+	yaffs_obj_t *obj = yaffs_inode_to_obj(inode);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_removexattr of object %d\n"),
+		obj->obj_id));
+
+
+	if (error == 0) {
+		int result;
+		dev = obj->my_dev;
+		yaffs_gross_lock(dev);
+		result = yaffs_remove_xattrib(obj, name);
+		if(result == YAFFS_OK)
+			error = 0;
+		else if(result < 0)
+			error = result;
+		yaffs_gross_unlock(dev);
+
+	}
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_removexattr done returning %d\n"),error));
+
+	return error;
+}
+
+ssize_t yaffs_listxattr(struct dentry *dentry, char *buff, size_t size)
+{
+	struct inode *inode = dentry->d_inode;
+	int error = 0;
+	yaffs_dev_t *dev;
+	yaffs_obj_t *obj = yaffs_inode_to_obj(inode);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_listxattr of object %d\n"),
+		obj->obj_id));
+
+
+	if (error == 0) {
+		dev = obj->my_dev;
+		yaffs_gross_lock(dev);
+		error = yaffs_list_xattrib(obj, buff, size);
+		yaffs_gross_unlock(dev);
+
+	}
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_listxattr done returning %d\n"),error));
+
+	return error;
+}
+
+#endif
+
+
+static int yaffs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	yaffs_dev_t *dev = yaffs_dentry_to_obj(dentry)->my_dev;
+	struct super_block *sb = dentry->d_sb;
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_statfs\n")));
+
+	yaffs_gross_lock(dev);
+
+	buf->f_type = YAFFS_MAGIC;
+	buf->f_bsize = sb->s_blocksize;
+	buf->f_namelen = 255;
+
+	if (dev->data_bytes_per_chunk & (dev->data_bytes_per_chunk - 1)) {
+		/* Do this if chunk size is not a power of 2 */
+
+		uint64_t bytes_in_dev;
+		uint64_t bytes_free;
+
+		bytes_in_dev = ((uint64_t)((dev->param.end_block - dev->param.start_block + 1))) *
+			((uint64_t)(dev->param.chunks_per_block * dev->data_bytes_per_chunk));
+
+		do_div(bytes_in_dev, sb->s_blocksize); /* bytes_in_dev becomes the number of blocks */
+		buf->f_blocks = bytes_in_dev;
+
+		bytes_free  = ((uint64_t)(yaffs_get_n_free_chunks(dev))) *
+			((uint64_t)(dev->data_bytes_per_chunk));
+
+		do_div(bytes_free, sb->s_blocksize);
+
+		buf->f_bfree = bytes_free;
+
+	} else if (sb->s_blocksize > dev->data_bytes_per_chunk) {
+
+		buf->f_blocks =
+			(dev->param.end_block - dev->param.start_block + 1) *
+			dev->param.chunks_per_block /
+			(sb->s_blocksize / dev->data_bytes_per_chunk);
+		buf->f_bfree =
+			yaffs_get_n_free_chunks(dev) /
+			(sb->s_blocksize / dev->data_bytes_per_chunk);
+	} else {
+		buf->f_blocks =
+			(dev->param.end_block - dev->param.start_block + 1) *
+			dev->param.chunks_per_block *
+			(dev->data_bytes_per_chunk / sb->s_blocksize);
+
+		buf->f_bfree =
+			yaffs_get_n_free_chunks(dev) *
+			(dev->data_bytes_per_chunk / sb->s_blocksize);
+	}
+
+	buf->f_files = 0;
+	buf->f_ffree = 0;
+	buf->f_bavail = buf->f_bfree;
+
+	yaffs_gross_unlock(dev);
+	return 0;
+}
+
+
+
+static void yaffs_flush_inodes(struct super_block *sb)
+{
+	struct inode *iptr;
+	yaffs_obj_t *obj;
+	
+	list_for_each_entry(iptr,&sb->s_inodes, i_sb_list){
+		obj = yaffs_inode_to_obj(iptr);
+		if(obj){
+			T(YAFFS_TRACE_OS, (TSTR("flushing obj %d\n"),
+				obj->obj_id));
+			yaffs_flush_file(obj,1,0);
+		}
+	}
+}
+
+
+static void yaffs_flush_super(struct super_block *sb, int do_checkpoint)
+{
+	yaffs_dev_t *dev = yaffs_super_to_dev(sb);	
+	if(!dev)
+		return;
+	
+	yaffs_flush_inodes(sb);
+	yaffs_update_dirty_dirs(dev);
+	yaffs_flush_whole_cache(dev);
+	if(do_checkpoint)
+		yaffs_checkpoint_save(dev);
+}
+
+
+static unsigned yaffs_bg_gc_urgency(yaffs_dev_t *dev)
+{
+	unsigned erased_chunks = dev->n_erased_blocks * dev->param.chunks_per_block;
+	struct yaffs_linux_context *context = yaffs_dev_to_lc(dev);
+	unsigned scattered = 0; /* Free chunks not in an erased block */
+
+	if(erased_chunks < dev->n_free_chunks)
+		scattered = (dev->n_free_chunks - erased_chunks);
+
+	if(!context->bg_running)
+		return 0;
+	else if(scattered < (dev->param.chunks_per_block * 2))
+		return 0;
+	else if(erased_chunks > dev->n_free_chunks/2)
+		return 0;
+	else if(erased_chunks > dev->n_free_chunks/4)
+		return 1;
+	else
+		return 2;
+}
+
+static int yaffs_do_sync_fs(struct super_block *sb,
+				int request_checkpoint)
+{
+
+	yaffs_dev_t *dev = yaffs_super_to_dev(sb);
+	unsigned int oneshot_checkpoint = (yaffs_auto_checkpoint & 4);
+	unsigned gc_urgent = yaffs_bg_gc_urgency(dev);
+	int do_checkpoint;
+
+	T(YAFFS_TRACE_OS | YAFFS_TRACE_SYNC | YAFFS_TRACE_BACKGROUND,
+		(TSTR("yaffs_do_sync_fs: gc-urgency %d %s %s%s\n"),
+		gc_urgent,
+		sb->s_dirt ? "dirty" : "clean",
+		request_checkpoint ? "checkpoint requested" : "no checkpoint",
+		oneshot_checkpoint ? " one-shot" : "" ));
+
+	yaffs_gross_lock(dev);
+	do_checkpoint = ((request_checkpoint && !gc_urgent) ||
+			oneshot_checkpoint) &&
+			!dev->is_checkpointed;
+
+	if (sb->s_dirt || do_checkpoint) {
+		yaffs_flush_super(sb, !dev->is_checkpointed && do_checkpoint);
+		sb->s_dirt = 0;
+		if(oneshot_checkpoint)
+			yaffs_auto_checkpoint &= ~4;
+	}
+	yaffs_gross_unlock(dev);
+
+	return 0;
+}
+
+/*
+ * yaffs background thread functions .
+ * yaffs_bg_thread_fn() the thread function
+ * yaffs_bg_start() launches the background thread.
+ * yaffs_bg_stop() cleans up the background thread.
+ *
+ * NB: 
+ * The thread should only run after the yaffs is initialised
+ * The thread should be stopped before yaffs is unmounted.
+ * The thread should not do any writing while the fs is in read only.
+ */
+
+
+void yaffs_background_waker(unsigned long data)
+{
+	wake_up_process((struct task_struct *)data);
+}
+
+static int yaffs_bg_thread_fn(void *data)
+{
+	yaffs_dev_t *dev = (yaffs_dev_t *)data;
+	struct yaffs_linux_context *context = yaffs_dev_to_lc(dev);
+	unsigned long now = jiffies;
+	unsigned long next_dir_update = now;
+	unsigned long next_gc = now;
+	unsigned long expires;
+	unsigned int urgency;
+
+	int gc_result;
+	struct timer_list timer;
+
+	T(YAFFS_TRACE_BACKGROUND,
+		(TSTR("yaffs_background starting for dev %p\n"),
+		(void *)dev));
+
+	set_freezable();
+	while(context->bg_running){
+		T(YAFFS_TRACE_BACKGROUND,
+			(TSTR("yaffs_background\n")));
+
+		if(kthread_should_stop())
+			break;
+
+		if(try_to_freeze())
+			continue;
+
+		yaffs_gross_lock(dev);
+
+		now = jiffies;
+
+		if(time_after(now, next_dir_update) && yaffs_bg_enable){
+			yaffs_update_dirty_dirs(dev);
+			next_dir_update = now + HZ;
+		}
+
+		if(time_after(now,next_gc) && yaffs_bg_enable){
+			if(!dev->is_checkpointed){
+				urgency = yaffs_bg_gc_urgency(dev);
+				gc_result = yaffs_bg_gc(dev, urgency);
+				if(urgency > 1)
+					next_gc = now + HZ/20+1;
+				else if(urgency > 0)
+					next_gc = now + HZ/10+1;
+				else
+					next_gc = now + HZ * 2;
+			} else /*
+				* gc not running so set to next_dir_update
+				* to cut down on wake ups
+				*/
+				next_gc = next_dir_update;
+		}
+		yaffs_gross_unlock(dev);
+		expires = next_dir_update;
+		if (time_before(next_gc,expires))
+			expires = next_gc;
+		if(time_before(expires,now))
+			expires = now + HZ;
+
+		Y_INIT_TIMER(&timer);
+		timer.expires = expires+1;
+		timer.data = (unsigned long) current;
+		timer.function = yaffs_background_waker;
+
+                set_current_state(TASK_INTERRUPTIBLE);
+		add_timer(&timer);
+		schedule();
+		del_timer_sync(&timer);
+	}
+
+	return 0;
+}
+
+static int yaffs_bg_start(yaffs_dev_t *dev)
+{
+	int retval = 0;
+	struct yaffs_linux_context *context = yaffs_dev_to_lc(dev);
+
+	if(dev->read_only)
+		return -1;
+
+	context->bg_running = 1;
+
+	context->bg_thread = kthread_run(yaffs_bg_thread_fn,
+	                        (void *)dev,"yaffs-bg-%d",context->mount_id);
+
+	if(IS_ERR(context->bg_thread)){
+		retval = PTR_ERR(context->bg_thread);
+		context->bg_thread = NULL;
+		context->bg_running = 0;
+	}
+	return retval;
+}
+
+static void yaffs_bg_stop(yaffs_dev_t *dev)
+{
+	struct yaffs_linux_context *ctxt = yaffs_dev_to_lc(dev);
+
+	ctxt->bg_running = 0;
+
+	if( ctxt->bg_thread){
+		kthread_stop(ctxt->bg_thread);
+		ctxt->bg_thread = NULL;
+	}
+}
+
+
+static void yaffs_write_super(struct super_block *sb)
+{
+	unsigned request_checkpoint = (yaffs_auto_checkpoint >= 2);
+
+	T(YAFFS_TRACE_OS | YAFFS_TRACE_SYNC | YAFFS_TRACE_BACKGROUND,
+		(TSTR("yaffs_write_super%s\n"),
+		request_checkpoint ? " checkpt" : ""));
+
+	yaffs_do_sync_fs(sb, request_checkpoint);
+
+}
+
+
+static int yaffs_sync_fs(struct super_block *sb, int wait)
+{
+	unsigned request_checkpoint = (yaffs_auto_checkpoint >= 1);
+
+	T(YAFFS_TRACE_OS | YAFFS_TRACE_SYNC,
+		(TSTR("yaffs_sync_fs%s\n"),
+		request_checkpoint ? " checkpt" : ""));
+
+	yaffs_do_sync_fs(sb, request_checkpoint);
+
+	return 0;
+}
+
+static struct inode *yaffs_iget(struct super_block *sb, unsigned long ino)
+{
+	struct inode *inode;
+	yaffs_obj_t *obj;
+	yaffs_dev_t *dev = yaffs_super_to_dev(sb);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_iget for %lu\n"), ino));
+
+	inode = iget_locked(sb, ino);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+	if (!(inode->i_state & I_NEW))
+		return inode;
+
+	/* NB This is called as a side effect of other functions, but
+	 * we had to release the lock to prevent deadlocks, so
+	 * need to lock again.
+	 */
+
+	yaffs_gross_lock(dev);
+
+	obj = yaffs_find_by_number(dev, inode->i_ino);
+
+	yaffs_fill_inode_from_obj(inode, obj);
+
+	yaffs_gross_unlock(dev);
+
+	unlock_new_inode(inode);
+	return inode;
+}
+
+static YLIST_HEAD(yaffs_context_list);
+struct semaphore yaffs_context_lock;
+
+static void yaffs_put_super(struct super_block *sb)
+{
+	yaffs_dev_t *dev = yaffs_super_to_dev(sb);
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_put_super\n")));
+
+	T(YAFFS_TRACE_OS | YAFFS_TRACE_BACKGROUND,
+		(TSTR("Shutting down yaffs background thread\n")));
+	yaffs_bg_stop(dev);
+	T(YAFFS_TRACE_OS | YAFFS_TRACE_BACKGROUND,
+		(TSTR("yaffs background thread shut down\n")));
+
+	yaffs_gross_lock(dev);
+
+	yaffs_flush_super(sb,1);
+
+	if (yaffs_dev_to_lc(dev)->put_super_fn)
+		yaffs_dev_to_lc(dev)->put_super_fn(sb);
+
+
+	yaffs_deinitialise(dev);
+
+	yaffs_gross_unlock(dev);
+
+	down(&yaffs_context_lock);
+	ylist_del_init(&(yaffs_dev_to_lc(dev)->context_list));
+	up(&yaffs_context_lock);
+
+	if (yaffs_dev_to_lc(dev)->spare_buffer) {
+		YFREE(yaffs_dev_to_lc(dev)->spare_buffer);
+		yaffs_dev_to_lc(dev)->spare_buffer = NULL;
+	}
+
+	kfree(dev);
+}
+
+
+static void yaffs_mtd_put_super(struct super_block *sb)
+{
+	struct mtd_info *mtd = yaffs_dev_to_mtd(yaffs_super_to_dev(sb));
+
+	if (mtd->sync)
+		mtd->sync(mtd);
+
+	put_mtd_device(mtd);
+}
+
+
+static void yaffs_touch_super(yaffs_dev_t *dev)
+{
+	struct super_block *sb = yaffs_dev_to_lc(dev)->super;
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_touch_super() sb = %p\n"), sb));
+	if (sb)
+		sb->s_dirt = 1;
+}
+
+typedef struct {
+	int inband_tags;
+	int skip_checkpoint_read;
+	int skip_checkpoint_write;
+	int no_cache;
+	int tags_ecc_on;
+	int tags_ecc_overridden;
+	int lazy_loading_enabled;
+	int lazy_loading_overridden;
+	int empty_lost_and_found;
+	int empty_lost_and_found_overridden;
+} yaffs_options;
+
+#define MAX_OPT_LEN 30
+static int yaffs_parse_options(yaffs_options *options, const char *options_str)
+{
+	char cur_opt[MAX_OPT_LEN + 1];
+	int p;
+	int error = 0;
+
+	/* Parse through the options which is a comma seperated list */
+
+	while (options_str && *options_str && !error) {
+		memset(cur_opt, 0, MAX_OPT_LEN + 1);
+		p = 0;
+
+		while(*options_str == ',')
+			options_str++;
+
+		while (*options_str && *options_str != ',') {
+			if (p < MAX_OPT_LEN) {
+				cur_opt[p] = *options_str;
+				p++;
+			}
+			options_str++;
+		}
+
+		if (!strcmp(cur_opt, "inband-tags"))
+			options->inband_tags = 1;
+		else if (!strcmp(cur_opt, "tags-ecc-off")){
+			options->tags_ecc_on = 0;
+			options->tags_ecc_overridden=1;
+		} else if (!strcmp(cur_opt, "tags-ecc-on")){
+			options->tags_ecc_on = 1;
+			options->tags_ecc_overridden = 1;
+		} else if (!strcmp(cur_opt, "lazy-loading-off")){
+			options->lazy_loading_enabled = 0;
+			options->lazy_loading_overridden=1;
+		} else if (!strcmp(cur_opt, "lazy-loading-on")){
+			options->lazy_loading_enabled = 1;
+			options->lazy_loading_overridden = 1;
+		} else if (!strcmp(cur_opt, "empty-lost-and-found-off")){
+			options->empty_lost_and_found = 0;
+			options->empty_lost_and_found_overridden=1;
+		} else if (!strcmp(cur_opt, "empty-lost-and-found-on")){
+			options->empty_lost_and_found = 1;
+			options->empty_lost_and_found_overridden=1;
+		} else if (!strcmp(cur_opt, "no-cache"))
+			options->no_cache = 1;
+		else if (!strcmp(cur_opt, "no-checkpoint-read"))
+			options->skip_checkpoint_read = 1;
+		else if (!strcmp(cur_opt, "no-checkpoint-write"))
+			options->skip_checkpoint_write = 1;
+		else if (!strcmp(cur_opt, "no-checkpoint")) {
+			options->skip_checkpoint_read = 1;
+			options->skip_checkpoint_write = 1;
+		} else {
+			printk(KERN_INFO "yaffs: Bad mount option \"%s\"\n",
+					cur_opt);
+			error = 1;
+		}
+	}
+
+	return error;
+}
+
+static struct super_block *yaffs_internal_read_super(int yaffs_version,
+						struct super_block *sb,
+						void *data, int silent)
+{
+	int nBlocks;
+	struct inode *inode = NULL;
+	struct dentry *root;
+	yaffs_dev_t *dev = 0;
+	char devname_buf[BDEVNAME_SIZE + 1];
+	struct mtd_info *mtd;
+	int err;
+	char *data_str = (char *)data;
+	struct yaffs_linux_context *context = NULL;
+	yaffs_param_t *param;
+
+	int read_only = 0;
+
+	yaffs_options options;
+
+	unsigned mount_id;
+	int found;
+	struct yaffs_linux_context *context_iterator;
+	struct ylist_head *l;
+
+	sb->s_magic = YAFFS_MAGIC;
+	sb->s_op = &yaffs_super_ops;
+	sb->s_flags |= MS_NOATIME;
+
+	read_only =((sb->s_flags & MS_RDONLY) != 0);
+
+	sb->s_export_op = &yaffs_export_ops;
+
+	if (!sb)
+		printk(KERN_INFO "yaffs: sb is NULL\n");
+	else if (!sb->s_dev)
+		printk(KERN_INFO "yaffs: sb->s_dev is NULL\n");
+	else if (!yaffs_devname(sb, devname_buf))
+		printk(KERN_INFO "yaffs: devname is NULL\n");
+	else
+		printk(KERN_INFO "yaffs: dev is %d name is \"%s\" %s\n",
+		       sb->s_dev,
+		       yaffs_devname(sb, devname_buf),
+		       read_only ? "ro" : "rw");
+
+	if (!data_str)
+		data_str = "";
+
+	printk(KERN_INFO "yaffs: passed flags \"%s\"\n", data_str);
+
+	memset(&options, 0, sizeof(options));
+
+	if (yaffs_parse_options(&options, data_str)) {
+		/* Option parsing failed */
+		return NULL;
+	}
+
+
+	sb->s_blocksize = PAGE_CACHE_SIZE;
+	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_read_super: Using yaffs%d\n"), yaffs_version));
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_read_super: block size %d\n"),
+		(int)(sb->s_blocksize)));
+
+	T(YAFFS_TRACE_ALWAYS,
+		(TSTR("yaffs: Attempting MTD mount of %u.%u,\"%s\"\n"),
+	       MAJOR(sb->s_dev), MINOR(sb->s_dev),
+	       yaffs_devname(sb, devname_buf)));
+
+	/* Check it's an mtd device..... */
+	if (MAJOR(sb->s_dev) != MTD_BLOCK_MAJOR)
+		return NULL;	/* This isn't an mtd device */
+
+	/* Get the device */
+	mtd = get_mtd_device(NULL, MINOR(sb->s_dev));
+	if (!mtd) {
+		T(YAFFS_TRACE_ALWAYS,
+			(TSTR("yaffs: MTD device #%u doesn't appear to exist\n"),
+			MINOR(sb->s_dev)));
+		return NULL;
+	}
+	/* Check it's NAND */
+	if (mtd->type != MTD_NANDFLASH) {
+		T(YAFFS_TRACE_ALWAYS,
+			(TSTR("yaffs: MTD device is not NAND it's type %d\n"),
+			mtd->type));
+		return NULL;
+	}
+
+	T(YAFFS_TRACE_OS, (TSTR(" erase %p\n"), mtd->erase));
+	T(YAFFS_TRACE_OS, (TSTR(" read %p\n"), mtd->read));
+	T(YAFFS_TRACE_OS, (TSTR(" write %p\n"), mtd->write));
+	T(YAFFS_TRACE_OS, (TSTR(" readoob %p\n"), mtd->read_oob));
+	T(YAFFS_TRACE_OS, (TSTR(" writeoob %p\n"), mtd->write_oob));
+	T(YAFFS_TRACE_OS, (TSTR(" block_isbad %p\n"), mtd->block_isbad));
+	T(YAFFS_TRACE_OS, (TSTR(" block_markbad %p\n"), mtd->block_markbad));
+	T(YAFFS_TRACE_OS, (TSTR(" %s %d\n"), WRITE_SIZE_STR, WRITE_SIZE(mtd)));
+	T(YAFFS_TRACE_OS, (TSTR(" oobsize %d\n"), mtd->oobsize));
+	T(YAFFS_TRACE_OS, (TSTR(" erasesize %d\n"), mtd->erasesize));
+	T(YAFFS_TRACE_OS, (TSTR(" size %lld\n"), mtd->size));
+
+#ifdef CONFIG_YAFFS_AUTO_YAFFS2
+
+	if (yaffs_version == 1 && WRITE_SIZE(mtd) >= 2048) {
+		T(YAFFS_TRACE_ALWAYS,
+			(TSTR("yaffs: auto selecting yaffs2\n")));
+		yaffs_version = 2;
+	}
+
+	/* Added NCB 26/5/2006 for completeness */
+	if (yaffs_version == 2 && !options.inband_tags && WRITE_SIZE(mtd) == 512) {
+		T(YAFFS_TRACE_ALWAYS,
+			(TSTR("yaffs: auto selecting yaffs1\n")));
+		yaffs_version = 1;
+	}
+
+#endif
+
+	if (yaffs_version == 2) {
+		/* Check for version 2 style functions */
+		if (!mtd->erase ||
+		    !mtd->block_isbad ||
+		    !mtd->block_markbad ||
+		    !mtd->read ||
+		    !mtd->write ||
+		    !mtd->read_oob || !mtd->write_oob) {
+			T(YAFFS_TRACE_ALWAYS,
+			  (TSTR("yaffs: MTD device does not support required "
+			   "functions\n")));
+			return NULL;
+		}
+
+		if ((WRITE_SIZE(mtd) < YAFFS_MIN_YAFFS2_CHUNK_SIZE ||
+		    mtd->oobsize < YAFFS_MIN_YAFFS2_SPARE_SIZE) &&
+		    !options.inband_tags) {
+			T(YAFFS_TRACE_ALWAYS,
+			  (TSTR("yaffs: MTD device does not have the "
+			   "right page sizes\n")));
+			return NULL;
+		}
+	} else {
+		/* Check for V1 style functions */
+		if (!mtd->erase ||
+		    !mtd->read ||
+		    !mtd->write ||
+		    !mtd->read_oob || !mtd->write_oob) {
+			T(YAFFS_TRACE_ALWAYS,
+			  (TSTR("yaffs: MTD device does not support required "
+			   "functions\n")));
+			return NULL;
+		}
+
+		if (WRITE_SIZE(mtd) < YAFFS_BYTES_PER_CHUNK ||
+		    mtd->oobsize != YAFFS_BYTES_PER_SPARE) {
+			T(YAFFS_TRACE_ALWAYS,
+			  (TSTR("yaffs: MTD device does not support have the "
+			   "right page sizes\n")));
+			return NULL;
+		}
+	}
+
+	/* OK, so if we got here, we have an MTD that's NAND and looks
+	 * like it has the right capabilities
+	 * Set the yaffs_dev_t up for mtd
+	 */
+
+	if (!read_only && !(mtd->flags & MTD_WRITEABLE)){
+		read_only = 1;
+		printk(KERN_INFO "yaffs: mtd is read only, setting superblock read only");
+		sb->s_flags |= MS_RDONLY;
+	}
+
+	dev = kmalloc(sizeof(yaffs_dev_t), GFP_KERNEL);
+	context = kmalloc(sizeof(struct yaffs_linux_context),GFP_KERNEL);
+	
+	if(!dev || !context ){
+		if(dev)
+			kfree(dev);
+		if(context)
+			kfree(context);
+		dev = NULL;
+		context = NULL;
+	}
+
+	if (!dev) {
+		/* Deep shit could not allocate device structure */
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR("yaffs_read_super: Failed trying to allocate "
+		   "yaffs_dev_t. \n")));
+		return NULL;
+	}
+	memset(dev, 0, sizeof(yaffs_dev_t));
+	param = &(dev->param);
+
+	memset(context,0,sizeof(struct yaffs_linux_context));
+	dev->os_context = context;
+	YINIT_LIST_HEAD(&(context->context_list));
+	context->dev = dev;
+	context->super = sb;
+
+	dev->read_only = read_only;
+
+	sb->s_fs_info = dev;
+	
+	dev->driver_context = mtd;
+	param->name = mtd->name;
+
+	/* Set up the memory size parameters.... */
+
+	nBlocks = YCALCBLOCKS(mtd->size, (YAFFS_CHUNKS_PER_BLOCK * YAFFS_BYTES_PER_CHUNK));
+
+	param->start_block = 0;
+	param->end_block = nBlocks - 1;
+	param->chunks_per_block = YAFFS_CHUNKS_PER_BLOCK;
+	param->total_bytes_per_chunk = YAFFS_BYTES_PER_CHUNK;
+	param->n_reserved_blocks = 5;
+	param->n_caches = (options.no_cache) ? 0 : 10;
+	param->inband_tags = options.inband_tags;
+
+#ifdef CONFIG_YAFFS_DISABLE_LAZY_LOAD
+	param->disable_lazy_load = 1;
+#endif
+#ifdef CONFIG_YAFFS_XATTR
+	param->enable_xattr = 1;
+#endif
+	if(options.lazy_loading_overridden)
+		param->disable_lazy_load = !options.lazy_loading_enabled;
+
+#ifdef CONFIG_YAFFS_DISABLE_TAGS_ECC
+	param->no_tags_ecc = 1;
+#endif
+
+#ifdef CONFIG_YAFFS_DISABLE_BACKGROUND
+#else
+	param->defered_dir_update = 1;
+#endif
+
+	if(options.tags_ecc_overridden)
+		param->no_tags_ecc = !options.tags_ecc_on;
+
+#ifdef CONFIG_YAFFS_EMPTY_LOST_AND_FOUND
+	param->empty_lost_n_found = 1;
+#endif
+
+#ifdef CONFIG_YAFFS_DISABLE_BLOCK_REFRESHING
+	param->refresh_period = 0;
+#else
+	param->refresh_period = 500;
+#endif
+
+#ifdef CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED
+	param->always_check_erased = 1;
+#endif
+
+	if(options.empty_lost_and_found_overridden)
+		param->empty_lost_n_found = options.empty_lost_and_found;
+
+	/* ... and the functions. */
+	if (yaffs_version == 2) {
+		param->write_chunk_tags_fn =
+		    nandmtd2_write_chunk_tags;
+		param->read_chunk_tags_fn =
+		    nandmtd2_read_chunk_tags;
+		param->bad_block_fn = nandmtd2_mark_block_bad;
+		param->query_block_fn = nandmtd2_query_block;
+		yaffs_dev_to_lc(dev)->spare_buffer = YMALLOC(mtd->oobsize);
+		param->is_yaffs2 = 1;
+		param->total_bytes_per_chunk = mtd->writesize;
+		param->chunks_per_block = mtd->erasesize / mtd->writesize;
+		nBlocks = YCALCBLOCKS(mtd->size, mtd->erasesize);
+
+		param->start_block = 0;
+		param->end_block = nBlocks - 1;
+	} else {
+		/* use the MTD interface in yaffs_mtdif1.c */
+		param->write_chunk_tags_fn =
+			nandmtd1_write_chunk_tags;
+		param->read_chunk_tags_fn =
+			nandmtd1_read_chunk_tags;
+		param->bad_block_fn = nandmtd1_mark_block_bad;
+		param->query_block_fn = nandmtd1_query_block;
+		param->is_yaffs2 = 0;
+	}
+	/* ... and common functions */
+	param->erase_fn = nandmtd_erase_block;
+	param->initialise_flash_fn = nandmtd_initialise;
+
+	yaffs_dev_to_lc(dev)->put_super_fn = yaffs_mtd_put_super;
+
+	param->sb_dirty_fn = yaffs_touch_super;
+	param->gc_control = yaffs_gc_control_callback;
+
+	yaffs_dev_to_lc(dev)->super= sb;
+	
+
+#ifndef CONFIG_YAFFS_DOES_ECC
+	param->use_nand_ecc = 1;
+#endif
+
+#ifdef CONFIG_YAFFS_DISABLE_WIDE_TNODES
+	param->wide_tnodes_disabled = 1;
+#endif
+
+	param->skip_checkpt_rd = options.skip_checkpoint_read;
+	param->skip_checkpt_wr = options.skip_checkpoint_write;
+
+	down(&yaffs_context_lock);
+	/* Get a mount id */
+	found = 0;
+	for(mount_id=0; ! found; mount_id++){
+		found = 1;
+		ylist_for_each(l,&yaffs_context_list){
+			context_iterator = ylist_entry(l,struct yaffs_linux_context,context_list);
+			if(context_iterator->mount_id == mount_id)
+				found = 0;
+		}
+	}
+	context->mount_id = mount_id;
+
+	ylist_add_tail(&(yaffs_dev_to_lc(dev)->context_list), &yaffs_context_list);
+	up(&yaffs_context_lock);
+
+        /* Directory search handling...*/
+        YINIT_LIST_HEAD(&(yaffs_dev_to_lc(dev)->search_contexts));
+        param->remove_obj_fn = yaffs_remove_obj_callback;
+
+	init_MUTEX(&(yaffs_dev_to_lc(dev)->gross_lock));
+
+	yaffs_gross_lock(dev);
+
+	err = yaffs_guts_initialise(dev);
+
+	T(YAFFS_TRACE_OS,
+	  (TSTR("yaffs_read_super: guts initialised %s\n"),
+	   (err == YAFFS_OK) ? "OK" : "FAILED"));
+	   
+	if(err == YAFFS_OK)
+		yaffs_bg_start(dev);
+		
+	if(!context->bg_thread)
+		param->defered_dir_update = 0;
+
+
+	/* Release lock before yaffs_get_inode() */
+	yaffs_gross_unlock(dev);
+
+	/* Create root inode */
+	if (err == YAFFS_OK)
+		inode = yaffs_get_inode(sb, S_IFDIR | 0755, 0,
+					yaffs_root(dev));
+
+	if (!inode)
+		return NULL;
+
+	inode->i_op = &yaffs_dir_inode_operations;
+	inode->i_fop = &yaffs_dir_operations;
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_read_super: got root inode\n")));
+
+	root = d_alloc_root(inode);
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_read_super: d_alloc_root done\n")));
+
+	if (!root) {
+		iput(inode);
+		return NULL;
+	}
+	sb->s_root = root;
+	sb->s_dirt = !dev->is_checkpointed;
+	T(YAFFS_TRACE_ALWAYS,
+		(TSTR("yaffs_read_super: is_checkpointed %d\n"),
+		dev->is_checkpointed));
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_read_super: done\n")));
+	return sb;
+}
+
+
+static int yaffs_internal_read_super_mtd(struct super_block *sb, void *data,
+					 int silent)
+{
+	return yaffs_internal_read_super(1, sb, data, silent) ? 0 : -EINVAL;
+}
+
+static int yaffs_read_super(struct file_system_type *fs,
+			    int flags, const char *dev_name,
+			    void *data, struct vfsmount *mnt)
+{
+
+	return get_sb_bdev(fs, flags, dev_name, data,
+			   yaffs_internal_read_super_mtd, mnt);
+}
+
+static struct file_system_type yaffs_fs_type = {
+	.owner = THIS_MODULE,
+	.name = "yaffs",
+	.get_sb = yaffs_read_super,
+	.kill_sb = kill_block_super,
+	.fs_flags = FS_REQUIRES_DEV,
+};
+
+
+#ifdef CONFIG_YAFFS_YAFFS2
+
+static int yaffs2_internal_read_super_mtd(struct super_block *sb, void *data,
+					  int silent)
+{
+	return yaffs_internal_read_super(2, sb, data, silent) ? 0 : -EINVAL;
+}
+
+static int yaffs2_read_super(struct file_system_type *fs,
+			int flags, const char *dev_name, void *data,
+			struct vfsmount *mnt)
+{
+	return get_sb_bdev(fs, flags, dev_name, data,
+			yaffs2_internal_read_super_mtd, mnt);
+}
+
+static struct file_system_type yaffs2_fs_type = {
+	.owner = THIS_MODULE,
+	.name = "yaffs2",
+	.get_sb = yaffs2_read_super,
+	.kill_sb = kill_block_super,
+	.fs_flags = FS_REQUIRES_DEV,
+};
+#endif				/* CONFIG_YAFFS_YAFFS2 */
+
+static struct proc_dir_entry *my_proc_entry;
+static struct proc_dir_entry *debug_proc_entry;
+
+static char *yaffs_dump_dev_part0(char *buf, yaffs_dev_t * dev)
+{
+	buf += sprintf(buf, "start_block........... %d\n", dev->param.start_block);
+	buf += sprintf(buf, "end_block............. %d\n", dev->param.end_block);
+	buf += sprintf(buf, "total_bytes_per_chunk. %d\n", dev->param.total_bytes_per_chunk);
+	buf += sprintf(buf, "use_nand_ecc.......... %d\n", dev->param.use_nand_ecc);
+	buf += sprintf(buf, "no_tags_ecc........... %d\n", dev->param.no_tags_ecc);
+	buf += sprintf(buf, "is_yaffs2............. %d\n", dev->param.is_yaffs2);
+	buf += sprintf(buf, "inband_tags........... %d\n", dev->param.inband_tags);
+	buf += sprintf(buf, "empty_lost_n_found.... %d\n", dev->param.empty_lost_n_found);
+	buf += sprintf(buf, "disable_lazy_load..... %d\n", dev->param.disable_lazy_load);
+	buf += sprintf(buf, "refresh_period........ %d\n", dev->param.refresh_period);
+	buf += sprintf(buf, "n_caches.............. %d\n", dev->param.n_caches);
+	buf += sprintf(buf, "n_reserved_blocks..... %d\n", dev->param.n_reserved_blocks);
+	buf += sprintf(buf, "always_check_erased... %d\n", dev->param.always_check_erased);
+
+	buf += sprintf(buf, "\n");
+
+	return buf;
+}
+
+
+static char *yaffs_dump_dev_part1(char *buf, yaffs_dev_t * dev)
+{
+	buf += sprintf(buf, "data_bytes_per_chunk.. %d\n", dev->data_bytes_per_chunk);
+	buf += sprintf(buf, "chunk_grp_bits........ %d\n", dev->chunk_grp_bits);
+	buf += sprintf(buf, "chunk_grp_size........ %d\n", dev->chunk_grp_size);
+	buf += sprintf(buf, "n_erased_blocks....... %d\n", dev->n_erased_blocks);
+	buf += sprintf(buf, "blocks_in_checkpt..... %d\n", dev->blocks_in_checkpt);
+	buf += sprintf(buf, "\n");
+	buf += sprintf(buf, "n_tnodes.............. %d\n", dev->n_tnodes);
+	buf += sprintf(buf, "n_obj................. %d\n", dev->n_obj);
+	buf += sprintf(buf, "n_free_chunks......... %d\n", dev->n_free_chunks);
+	buf += sprintf(buf, "\n");
+	buf += sprintf(buf, "n_page_writes......... %u\n", dev->n_page_writes);
+	buf += sprintf(buf, "n_page_reads.......... %u\n", dev->n_page_reads);
+	buf += sprintf(buf, "n_erasures............ %u\n", dev->n_erasures);
+	buf += sprintf(buf, "n_gc_copies........... %u\n", dev->n_gc_copies);
+	buf += sprintf(buf, "all_gcs............... %u\n", dev->all_gcs);
+	buf += sprintf(buf, "passive_gc_count...... %u\n", dev->passive_gc_count);
+	buf += sprintf(buf, "oldest_dirty_gc_count. %u\n", dev->oldest_dirty_gc_count);
+	buf += sprintf(buf, "n_gc_blocks........... %u\n", dev->n_gc_blocks);
+	buf += sprintf(buf, "bg_gcs................ %u\n", dev->bg_gcs);
+	buf += sprintf(buf, "n_retired_writes...... %u\n", dev->n_retired_writes);
+	buf += sprintf(buf, "n_retired_blocks...... %u\n", dev->n_retired_blocks);
+	buf += sprintf(buf, "n_ecc_fixed........... %u\n", dev->n_ecc_fixed);
+	buf += sprintf(buf, "n_ecc_unfixed......... %u\n", dev->n_ecc_unfixed);
+	buf += sprintf(buf, "n_tags_ecc_fixed...... %u\n", dev->n_tags_ecc_fixed);
+	buf += sprintf(buf, "n_tags_ecc_unfixed.... %u\n", dev->n_tags_ecc_unfixed);
+	buf += sprintf(buf, "cache_hits............ %u\n", dev->cache_hits);
+	buf += sprintf(buf, "n_deleted_files....... %u\n", dev->n_deleted_files);
+	buf += sprintf(buf, "n_unlinked_files...... %u\n", dev->n_unlinked_files);
+	buf += sprintf(buf, "refresh_count......... %u\n", dev->refresh_count);
+	buf += sprintf(buf, "n_bg_deletions........ %u\n", dev->n_bg_deletions);
+
+	return buf;
+}
+
+static int yaffs_proc_read(char *page,
+			   char **start,
+			   off_t offset, int count, int *eof, void *data)
+{
+	struct ylist_head *item;
+	char *buf = page;
+	int step = offset;
+	int n = 0;
+
+	/* Get proc_file_read() to step 'offset' by one on each sucessive call.
+	 * We use 'offset' (*ppos) to indicate where we are in dev_list.
+	 * This also assumes the user has posted a read buffer large
+	 * enough to hold the complete output; but that's life in /proc.
+	 */
+
+	*(int *)start = 1;
+
+	/* Print header first */
+	if (step == 0)
+		buf += sprintf(buf, "YAFFS built:" __DATE__ " " __TIME__"\n");
+	else if (step == 1)
+		buf += sprintf(buf,"\n");
+	else {
+		step-=2;
+		
+		down(&yaffs_context_lock);
+
+		/* Locate and print the Nth entry.  Order N-squared but N is small. */
+		ylist_for_each(item, &yaffs_context_list) {
+			struct yaffs_linux_context *dc = ylist_entry(item, struct yaffs_linux_context, context_list);
+			yaffs_dev_t *dev = dc->dev;
+
+			if (n < (step & ~1)) {
+				n+=2;
+				continue;
+			}
+			if((step & 1)==0){
+				buf += sprintf(buf, "\nDevice %d \"%s\"\n", n, dev->param.name);
+				buf = yaffs_dump_dev_part0(buf, dev);
+			} else
+				buf = yaffs_dump_dev_part1(buf, dev);
+			
+			break;
+		}
+		up(&yaffs_context_lock);
+	}
+
+	return buf - page < count ? buf - page : count;
+}
+
+static int yaffs_stats_proc_read(char *page,
+				char **start,
+				off_t offset, int count, int *eof, void *data)
+{
+	struct ylist_head *item;
+	char *buf = page;
+	int n = 0;
+
+	down(&yaffs_context_lock);
+
+	/* Locate and print the Nth entry.  Order N-squared but N is small. */
+	ylist_for_each(item, &yaffs_context_list) {
+		struct yaffs_linux_context *dc = ylist_entry(item, struct yaffs_linux_context, context_list);
+		yaffs_dev_t *dev = dc->dev;
+
+		int erased_chunks;
+
+		erased_chunks = dev->n_erased_blocks * dev->param.chunks_per_block;
+		
+		buf += sprintf(buf,"%d, %d, %d, %u, %u, %u, %u\n",
+				n, dev->n_free_chunks, erased_chunks,
+				dev->bg_gcs, dev->oldest_dirty_gc_count,
+				dev->n_obj, dev->n_tnodes);
+	}
+	up(&yaffs_context_lock);
+
+
+	return buf - page < count ? buf - page : count;
+}
+
+/**
+ * Set the verbosity of the warnings and error messages.
+ *
+ * Note that the names can only be a..z or _ with the current code.
+ */
+
+static struct {
+	char *mask_name;
+	unsigned mask_bitfield;
+} mask_flags[] = {
+	{"allocate", YAFFS_TRACE_ALLOCATE},
+	{"always", YAFFS_TRACE_ALWAYS},
+	{"background", YAFFS_TRACE_BACKGROUND},
+	{"bad_blocks", YAFFS_TRACE_BAD_BLOCKS},
+	{"buffers", YAFFS_TRACE_BUFFERS},
+	{"bug", YAFFS_TRACE_BUG},
+	{"checkpt", YAFFS_TRACE_CHECKPOINT},
+	{"deletion", YAFFS_TRACE_DELETION},
+	{"erase", YAFFS_TRACE_ERASE},
+	{"error", YAFFS_TRACE_ERROR},
+	{"gc_detail", YAFFS_TRACE_GC_DETAIL},
+	{"gc", YAFFS_TRACE_GC},
+	{"lock", YAFFS_TRACE_LOCK},
+	{"mtd", YAFFS_TRACE_MTD},
+	{"nandaccess", YAFFS_TRACE_NANDACCESS},
+	{"os", YAFFS_TRACE_OS},
+	{"scan_debug", YAFFS_TRACE_SCAN_DEBUG},
+	{"scan", YAFFS_TRACE_SCAN},
+	{"tracing", YAFFS_TRACE_TRACING},
+	{"sync", YAFFS_TRACE_SYNC},
+	{"write", YAFFS_TRACE_WRITE},
+
+	{"verify", YAFFS_TRACE_VERIFY},
+	{"verify_nand", YAFFS_TRACE_VERIFY_NAND},
+	{"verify_full", YAFFS_TRACE_VERIFY_FULL},
+	{"verify_all", YAFFS_TRACE_VERIFY_ALL},
+
+	{"all", 0xffffffff},
+	{"none", 0},
+	{NULL, 0},
+};
+
+#define MAX_MASK_NAME_LENGTH 40
+static int yaffs_proc_write_trace_options(struct file *file, const char *buf,
+					 unsigned long count, void *data)
+{
+	unsigned rg = 0, mask_bitfield;
+	char *end;
+	char *mask_name;
+	const char *x;
+	char substring[MAX_MASK_NAME_LENGTH + 1];
+	int i;
+	int done = 0;
+	int add, len = 0;
+	int pos = 0;
+
+	rg = yaffs_trace_mask;
+
+	while (!done && (pos < count)) {
+		done = 1;
+		while ((pos < count) && isspace(buf[pos]))
+			pos++;
+
+		switch (buf[pos]) {
+		case '+':
+		case '-':
+		case '=':
+			add = buf[pos];
+			pos++;
+			break;
+
+		default:
+			add = ' ';
+			break;
+		}
+		mask_name = NULL;
+
+		mask_bitfield = simple_strtoul(buf + pos, &end, 0);
+
+		if (end > buf + pos) {
+			mask_name = "numeral";
+			len = end - (buf + pos);
+			pos += len;
+			done = 0;
+		} else {
+			for (x = buf + pos, i = 0;
+			    (*x == '_' || (*x >= 'a' && *x <= 'z')) &&
+			    i < MAX_MASK_NAME_LENGTH; x++, i++, pos++)
+				substring[i] = *x;
+			substring[i] = '\0';
+
+			for (i = 0; mask_flags[i].mask_name != NULL; i++) {
+				if (strcmp(substring, mask_flags[i].mask_name) == 0) {
+					mask_name = mask_flags[i].mask_name;
+					mask_bitfield = mask_flags[i].mask_bitfield;
+					done = 0;
+					break;
+				}
+			}
+		}
+
+		if (mask_name != NULL) {
+			done = 0;
+			switch (add) {
+			case '-':
+				rg &= ~mask_bitfield;
+				break;
+			case '+':
+				rg |= mask_bitfield;
+				break;
+			case '=':
+				rg = mask_bitfield;
+				break;
+			default:
+				rg |= mask_bitfield;
+				break;
+			}
+		}
+	}
+
+	yaffs_trace_mask = rg | YAFFS_TRACE_ALWAYS;
+
+	printk(KERN_DEBUG "new trace = 0x%08X\n", yaffs_trace_mask);
+
+	if (rg & YAFFS_TRACE_ALWAYS) {
+		for (i = 0; mask_flags[i].mask_name != NULL; i++) {
+			char flag;
+			flag = ((rg & mask_flags[i].mask_bitfield) ==
+				mask_flags[i].mask_bitfield) ? '+' : '-';
+			printk(KERN_DEBUG "%c%s\n", flag, mask_flags[i].mask_name);
+		}
+	}
+
+	return count;
+}
+
+
+static int yaffs_proc_write(struct file *file, const char *buf,
+					 unsigned long count, void *data)
+{
+        return yaffs_proc_write_trace_options(file, buf, count, data);
+}
+
+/* Stuff to handle installation of file systems */
+struct file_system_to_install {
+	struct file_system_type *fst;
+	int installed;
+};
+
+static struct file_system_to_install fs_to_install[] = {
+	{&yaffs_fs_type, 0},
+	{&yaffs2_fs_type, 0},
+	{NULL, 0}
+};
+
+static int __init init_yaffs_fs(void)
+{
+	int error = 0;
+	struct file_system_to_install *fsinst;
+
+	T(YAFFS_TRACE_ALWAYS,
+	  (TSTR("yaffs built " __DATE__ " " __TIME__ " Installing. \n")));
+
+#ifdef CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED
+	T(YAFFS_TRACE_ALWAYS,
+	  (TSTR(" \n\n\n\nYAFFS-WARNING CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED selected.\n\n\n\n")));
+#endif
+
+
+
+
+	init_MUTEX(&yaffs_context_lock);
+
+	/* Install the proc_fs entries */
+	my_proc_entry = create_proc_entry("yaffs",
+					       S_IRUGO | S_IFREG,
+					       YPROC_ROOT);
+
+	if (my_proc_entry) {
+		my_proc_entry->write_proc = yaffs_proc_write;
+		my_proc_entry->read_proc = yaffs_proc_read;
+		my_proc_entry->data = NULL;
+	} else
+		return -ENOMEM;
+
+	debug_proc_entry = create_proc_entry("yaffs_stats",
+					       S_IRUGO | S_IFREG,
+					       YPROC_ROOT);
+
+	if (debug_proc_entry) {
+		debug_proc_entry->write_proc = NULL;
+		debug_proc_entry->read_proc = yaffs_stats_proc_read;
+		debug_proc_entry->data = NULL;
+	} else
+		return -ENOMEM;
+
+	/* Now add the file system entries */
+
+	fsinst = fs_to_install;
+
+	while (fsinst->fst && !error) {
+		error = register_filesystem(fsinst->fst);
+		if (!error)
+			fsinst->installed = 1;
+		fsinst++;
+	}
+
+	/* Any errors? uninstall  */
+	if (error) {
+		fsinst = fs_to_install;
+
+		while (fsinst->fst) {
+			if (fsinst->installed) {
+				unregister_filesystem(fsinst->fst);
+				fsinst->installed = 0;
+			}
+			fsinst++;
+		}
+	}
+
+	return error;
+}
+
+static void __exit exit_yaffs_fs(void)
+{
+
+	struct file_system_to_install *fsinst;
+
+	T(YAFFS_TRACE_ALWAYS,
+		(TSTR("yaffs built " __DATE__ " " __TIME__ " removing. \n")));
+
+	remove_proc_entry("yaffs", YPROC_ROOT);
+	remove_proc_entry("yaffs_stats", YPROC_ROOT);
+
+	fsinst = fs_to_install;
+
+	while (fsinst->fst) {
+		if (fsinst->installed) {
+			unregister_filesystem(fsinst->fst);
+			fsinst->installed = 0;
+		}
+		fsinst++;
+	}
+}
+
+module_init(init_yaffs_fs)
+module_exit(exit_yaffs_fs)
+
+MODULE_DESCRIPTION("YAFFS2 - a NAND specific flash file system");
+MODULE_AUTHOR("Charles Manning, Aleph One Ltd., 2002-2010");
+MODULE_LICENSE("GPL");
-- 
1.7.3.2.146.gca209

[PATCH 26/29] Staging: yaffs2: yaffs_yaffs1: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_yaffs1.c |  457 +++++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_yaffs1.h |   22 ++
 2 files changed, 479 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_yaffs1.c
 create mode 100644 drivers/staging/yaffs2/yaffs_yaffs1.h

diff --git a/drivers/staging/yaffs2/yaffs_yaffs1.c b/drivers/staging/yaffs2/yaffs_yaffs1.c
new file mode 100644
index 0000000..21933dc
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_yaffs1.c
@@ -0,0 +1,457 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_yaffs1.h"
+#include "yportenv.h"
+#include "yaffs_trace.h"
+#include "yaffs_bitmap.h"
+#include "yaffs_getblockinfo.h"
+#include "yaffs_nand.h"
+
+
+int yaffs1_scan(yaffs_dev_t *dev)
+{
+	yaffs_ext_tags tags;
+	int blk;
+	int result;
+
+	int chunk;
+	int c;
+	int deleted;
+	yaffs_block_state_t state;
+	yaffs_obj_t *hard_list = NULL;
+	yaffs_block_info_t *bi;
+	__u32 seq_number;
+	yaffs_obj_header *oh;
+	yaffs_obj_t *in;
+	yaffs_obj_t *parent;
+
+	int alloc_failed = 0;
+
+	struct yaffs_shadow_fixer_s *shadow_fixers = NULL;
+
+
+	__u8 *chunk_data;
+
+
+
+	T(YAFFS_TRACE_SCAN,
+	  (TSTR("yaffs1_scan starts  intstartblk %d intendblk %d..." TENDSTR),
+	   dev->internal_start_block, dev->internal_end_block));
+
+	chunk_data = yaffs_get_temp_buffer(dev, __LINE__);
+
+	dev->seq_number = YAFFS_LOWEST_SEQUENCE_NUMBER;
+
+	/* Scan all the blocks to determine their state */
+	bi = dev->block_info;
+	for (blk = dev->internal_start_block; blk <= dev->internal_end_block; blk++) {
+		yaffs_clear_chunk_bits(dev, blk);
+		bi->pages_in_use = 0;
+		bi->soft_del_pages = 0;
+
+		yaffs_query_init_block_state(dev, blk, &state, &seq_number);
+
+		bi->block_state = state;
+		bi->seq_number = seq_number;
+
+		if (bi->seq_number == YAFFS_SEQUENCE_BAD_BLOCK)
+			bi->block_state = state = YAFFS_BLOCK_STATE_DEAD;
+
+		T(YAFFS_TRACE_SCAN_DEBUG,
+		  (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
+		   state, seq_number));
+
+		if (state == YAFFS_BLOCK_STATE_DEAD) {
+			T(YAFFS_TRACE_BAD_BLOCKS,
+			  (TSTR("block %d is bad" TENDSTR), blk));
+		} else if (state == YAFFS_BLOCK_STATE_EMPTY) {
+			T(YAFFS_TRACE_SCAN_DEBUG,
+			  (TSTR("Block empty " TENDSTR)));
+			dev->n_erased_blocks++;
+			dev->n_free_chunks += dev->param.chunks_per_block;
+		}
+		bi++;
+	}
+
+	/* For each block.... */
+	for (blk= dev->internal_start_block; 
+		!alloc_failed && blk <= dev->internal_end_block;
+		blk++) {
+
+		YYIELD();
+
+		bi = yaffs_get_block_info(dev, blk);
+		state = bi->block_state;
+
+		deleted = 0;
+
+		/* For each chunk in each block that needs scanning....*/
+		for (c = 0; !alloc_failed && c < dev->param.chunks_per_block &&
+		     state == YAFFS_BLOCK_STATE_NEEDS_SCANNING; c++) {
+			/* Read the tags and decide what to do */
+			chunk = blk * dev->param.chunks_per_block + c;
+
+			result = yaffs_rd_chunk_tags_nand(dev, chunk, NULL,
+							&tags);
+
+			/* Let's have a good look at this chunk... */
+
+			if (tags.ecc_result == YAFFS_ECC_RESULT_UNFIXED || tags.is_deleted) {
+				/* YAFFS1 only...
+				 * A deleted chunk
+				 */
+				deleted++;
+				dev->n_free_chunks++;
+				/*T((" %d %d deleted\n",blk,c)); */
+			} else if (!tags.chunk_used) {
+				/* An unassigned chunk in the block
+				 * This means that either the block is empty or
+				 * this is the one being allocated from
+				 */
+
+				if (c == 0) {
+					/* We're looking at the first chunk in the block so the block is unused */
+					state = YAFFS_BLOCK_STATE_EMPTY;
+					dev->n_erased_blocks++;
+				} else {
+					/* this is the block being allocated from */
+					T(YAFFS_TRACE_SCAN,
+					  (TSTR
+					   (" Allocating from %d %d" TENDSTR),
+					   blk, c));
+					state = YAFFS_BLOCK_STATE_ALLOCATING;
+					dev->alloc_block = blk;
+					dev->alloc_page = c;
+					dev->alloc_block_finder = blk;
+					/* Set block finder here to encourage the allocator to go forth from here. */
+
+				}
+
+				dev->n_free_chunks += (dev->param.chunks_per_block - c);
+			} else if (tags.chunk_id > 0) {
+				/* chunk_id > 0 so it is a data chunk... */
+				unsigned int endpos;
+
+				yaffs_set_chunk_bit(dev, blk, c);
+				bi->pages_in_use++;
+
+				in = yaffs_find_or_create_by_number(dev,
+								      tags.
+								      obj_id,
+								      YAFFS_OBJECT_TYPE_FILE);
+				/* PutChunkIntoFile checks for a clash (two data chunks with
+				 * the same chunk_id).
+				 */
+
+				if (!in)
+					alloc_failed = 1;
+
+				if (in) {
+					if (!yaffs_put_chunk_in_file(in, tags.chunk_id, chunk, 1))
+						alloc_failed = 1;
+				}
+
+				endpos =
+				    (tags.chunk_id - 1) * dev->data_bytes_per_chunk +
+				    tags.n_bytes;
+				if (in &&
+				    in->variant_type == YAFFS_OBJECT_TYPE_FILE
+				    && in->variant.file_variant.scanned_size <
+				    endpos) {
+					in->variant.file_variant.
+					    scanned_size = endpos;
+					if (!dev->param.use_header_file_size) {
+						in->variant.file_variant.
+						    file_size =
+						    in->variant.file_variant.
+						    scanned_size;
+					}
+
+				}
+				/* T((" %d %d data %d %d\n",blk,c,tags.obj_id,tags.chunk_id));   */
+			} else {
+				/* chunk_id == 0, so it is an ObjectHeader.
+				 * Thus, we read in the object header and make the object
+				 */
+				yaffs_set_chunk_bit(dev, blk, c);
+				bi->pages_in_use++;
+
+				result = yaffs_rd_chunk_tags_nand(dev, chunk,
+								chunk_data,
+								NULL);
+
+				oh = (yaffs_obj_header *) chunk_data;
+
+				in = yaffs_find_by_number(dev,
+							      tags.obj_id);
+				if (in && in->variant_type != oh->type) {
+					/* This should not happen, but somehow
+					 * Wev'e ended up with an obj_id that has been reused but not yet
+					 * deleted, and worse still it has changed type. Delete the old object.
+					 */
+
+					yaffs_del_obj(in);
+
+					in = 0;
+				}
+
+				in = yaffs_find_or_create_by_number(dev,
+								      tags.
+								      obj_id,
+								      oh->type);
+
+				if (!in)
+					alloc_failed = 1;
+
+				if (in && oh->shadows_obj > 0) {
+
+					struct yaffs_shadow_fixer_s *fixer;
+					fixer = YMALLOC(sizeof(struct yaffs_shadow_fixer_s));
+					if (fixer) {
+						fixer->next = shadow_fixers;
+						shadow_fixers = fixer;
+						fixer->obj_id = tags.obj_id;
+						fixer->shadowed_id = oh->shadows_obj;
+						T(YAFFS_TRACE_SCAN,
+						  (TSTR
+						   (" Shadow fixer: %d shadows %d" TENDSTR),
+						   fixer->obj_id, fixer->shadowed_id));
+
+					}
+
+				}
+
+				if (in && in->valid) {
+					/* We have already filled this one. We have a duplicate and need to resolve it. */
+
+					unsigned existing_serial = in->serial;
+					unsigned new_serial = tags.serial_number;
+
+					if (((existing_serial + 1) & 3) == new_serial) {
+						/* Use new one - destroy the exisiting one */
+						yaffs_chunk_del(dev,
+								  in->hdr_chunk,
+								  1, __LINE__);
+						in->valid = 0;
+					} else {
+						/* Use existing - destroy this one. */
+						yaffs_chunk_del(dev, chunk, 1,
+								  __LINE__);
+					}
+				}
+
+				if (in && !in->valid &&
+				    (tags.obj_id == YAFFS_OBJECTID_ROOT ||
+				     tags.obj_id == YAFFS_OBJECTID_LOSTNFOUND)) {
+					/* We only load some info, don't fiddle with directory structure */
+					in->valid = 1;
+					in->variant_type = oh->type;
+
+					in->yst_mode = oh->yst_mode;
+#ifdef CONFIG_YAFFS_WINCE
+					in->win_atime[0] = oh->win_atime[0];
+					in->win_ctime[0] = oh->win_ctime[0];
+					in->win_mtime[0] = oh->win_mtime[0];
+					in->win_atime[1] = oh->win_atime[1];
+					in->win_ctime[1] = oh->win_ctime[1];
+					in->win_mtime[1] = oh->win_mtime[1];
+#else
+					in->yst_uid = oh->yst_uid;
+					in->yst_gid = oh->yst_gid;
+					in->yst_atime = oh->yst_atime;
+					in->yst_mtime = oh->yst_mtime;
+					in->yst_ctime = oh->yst_ctime;
+					in->yst_rdev = oh->yst_rdev;
+#endif
+					in->hdr_chunk = chunk;
+					in->serial = tags.serial_number;
+
+				} else if (in && !in->valid) {
+					/* we need to load this info */
+
+					in->valid = 1;
+					in->variant_type = oh->type;
+
+					in->yst_mode = oh->yst_mode;
+#ifdef CONFIG_YAFFS_WINCE
+					in->win_atime[0] = oh->win_atime[0];
+					in->win_ctime[0] = oh->win_ctime[0];
+					in->win_mtime[0] = oh->win_mtime[0];
+					in->win_atime[1] = oh->win_atime[1];
+					in->win_ctime[1] = oh->win_ctime[1];
+					in->win_mtime[1] = oh->win_mtime[1];
+#else
+					in->yst_uid = oh->yst_uid;
+					in->yst_gid = oh->yst_gid;
+					in->yst_atime = oh->yst_atime;
+					in->yst_mtime = oh->yst_mtime;
+					in->yst_ctime = oh->yst_ctime;
+					in->yst_rdev = oh->yst_rdev;
+#endif
+					in->hdr_chunk = chunk;
+					in->serial = tags.serial_number;
+
+					yaffs_set_obj_name_from_oh(in, oh);
+					in->dirty = 0;
+
+					/* directory stuff...
+					 * hook up to parent
+					 */
+
+					parent =
+					    yaffs_find_or_create_by_number
+					    (dev, oh->parent_obj_id,
+					     YAFFS_OBJECT_TYPE_DIRECTORY);
+					if (!parent)
+						alloc_failed = 1;
+					if (parent && parent->variant_type ==
+					    YAFFS_OBJECT_TYPE_UNKNOWN) {
+						/* Set up as a directory */
+						parent->variant_type =
+							YAFFS_OBJECT_TYPE_DIRECTORY;
+						YINIT_LIST_HEAD(&parent->variant.
+								dir_variant.
+								children);
+					} else if (!parent || parent->variant_type !=
+						   YAFFS_OBJECT_TYPE_DIRECTORY) {
+						/* Hoosterman, another problem....
+						 * We're trying to use a non-directory as a directory
+						 */
+
+						T(YAFFS_TRACE_ERROR,
+						  (TSTR
+						   ("yaffs tragedy: attempting to use non-directory as a directory in scan. Put in lost+found."
+						    TENDSTR)));
+						parent = dev->lost_n_found;
+					}
+
+					yaffs_add_obj_to_dir(parent, in);
+
+					if (0 && (parent == dev->del_dir ||
+						  parent == dev->unlinked_dir)) {
+						in->deleted = 1;	/* If it is unlinked at start up then it wants deleting */
+						dev->n_deleted_files++;
+					}
+					/* Note re hardlinks.
+					 * Since we might scan a hardlink before its equivalent object is scanned
+					 * we put them all in a list.
+					 * After scanning is complete, we should have all the objects, so we run through this
+					 * list and fix up all the chains.
+					 */
+
+					switch (in->variant_type) {
+					case YAFFS_OBJECT_TYPE_UNKNOWN:
+						/* Todo got a problem */
+						break;
+					case YAFFS_OBJECT_TYPE_FILE:
+						if (dev->param.use_header_file_size)
+
+							in->variant.file_variant.
+							    file_size =
+							    oh->file_size;
+
+						break;
+					case YAFFS_OBJECT_TYPE_HARDLINK:
+						in->variant.hardlink_variant.
+							equiv_id =
+							oh->equiv_id;
+						in->hard_links.next =
+							(struct ylist_head *)
+							hard_list;
+						hard_list = in;
+						break;
+					case YAFFS_OBJECT_TYPE_DIRECTORY:
+						/* Do nothing */
+						break;
+					case YAFFS_OBJECT_TYPE_SPECIAL:
+						/* Do nothing */
+						break;
+					case YAFFS_OBJECT_TYPE_SYMLINK:
+						in->variant.symlink_variant.alias =
+						    yaffs_clone_str(oh->alias);
+						if (!in->variant.symlink_variant.alias)
+							alloc_failed = 1;
+						break;
+					}
+
+				}
+			}
+		}
+
+		if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
+			/* If we got this far while scanning, then the block is fully allocated.*/
+			state = YAFFS_BLOCK_STATE_FULL;
+		}
+
+		if (state == YAFFS_BLOCK_STATE_ALLOCATING) {
+			/* If the block was partially allocated then treat it as fully allocated.*/
+			state = YAFFS_BLOCK_STATE_FULL;
+			dev->alloc_block = -1;
+		}
+
+		bi->block_state = state;
+
+		/* Now let's see if it was dirty */
+		if (bi->pages_in_use == 0 &&
+		    !bi->has_shrink_hdr &&
+		    bi->block_state == YAFFS_BLOCK_STATE_FULL) {
+			yaffs_block_became_dirty(dev, blk);
+		}
+
+	}
+
+
+	/* Ok, we've done all the scanning.
+	 * Fix up the hard link chains.
+	 * We should now have scanned all the objects, now it's time to add these
+	 * hardlinks.
+	 */
+
+	yaffs_link_fixup(dev, hard_list);
+
+	/* Fix up any shadowed objects */
+	{
+		struct yaffs_shadow_fixer_s *fixer;
+		yaffs_obj_t *obj;
+
+		while (shadow_fixers) {
+			fixer = shadow_fixers;
+			shadow_fixers = fixer->next;
+			/* Complete the rename transaction by deleting the shadowed object
+			 * then setting the object header to unshadowed.
+			 */
+			obj = yaffs_find_by_number(dev, fixer->shadowed_id);
+			if (obj)
+				yaffs_del_obj(obj);
+
+			obj = yaffs_find_by_number(dev, fixer->obj_id);
+
+			if (obj)
+				yaffs_update_oh(obj, NULL, 1, 0, 0, NULL);
+
+			YFREE(fixer);
+		}
+	}
+
+	yaffs_release_temp_buffer(dev, chunk_data, __LINE__);
+
+	if (alloc_failed)
+		return YAFFS_FAIL;
+
+	T(YAFFS_TRACE_SCAN, (TSTR("yaffs1_scan ends" TENDSTR)));
+
+
+	return YAFFS_OK;
+}
+
diff --git a/drivers/staging/yaffs2/yaffs_yaffs1.h b/drivers/staging/yaffs2/yaffs_yaffs1.h
new file mode 100644
index 0000000..1f60b0c
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_yaffs1.h
@@ -0,0 +1,22 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_YAFFS1_H__
+#define __YAFFS_YAFFS1_H__
+
+#include "yaffs_guts.h"
+int yaffs1_scan(yaffs_dev_t *dev);
+
+#endif
-- 
1.7.3.2.146.gca209

[PATCH 27/29] Staging: yaffs2: yaffs_yaffs2: Add files

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_yaffs2.c | 1541 +++++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_yaffs2.h |   38 +
 2 files changed, 1579 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_yaffs2.c
 create mode 100644 drivers/staging/yaffs2/yaffs_yaffs2.h

diff --git a/drivers/staging/yaffs2/yaffs_yaffs2.c b/drivers/staging/yaffs2/yaffs_yaffs2.c
new file mode 100644
index 0000000..76623ad
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_yaffs2.c
@@ -0,0 +1,1541 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+
+#include "yaffs_guts.h"
+#include "yaffs_trace.h"
+#include "yaffs_yaffs2.h"
+#include "yaffs_checkptrw.h"
+#include "yaffs_bitmap.h"
+#include "yaffs_qsort.h"
+#include "yaffs_nand.h"
+#include "yaffs_getblockinfo.h"
+#include "yaffs_verify.h"
+
+/*
+ * Checkpoints are really no benefit on very small partitions.
+ *
+ * To save space on small partitions don't bother with checkpoints unless
+ * the partition is at least this big.
+ */
+#define YAFFS_CHECKPOINT_MIN_BLOCKS 60
+
+#define YAFFS_SMALL_HOLE_THRESHOLD 4
+
+
+/*
+ * Oldest Dirty Sequence Number handling.
+ */
+ 
+/* yaffs_calc_oldest_dirty_seq()
+ * yaffs2_find_oldest_dirty_seq()
+ * Calculate the oldest dirty sequence number if we don't know it.
+ */
+void yaffs_calc_oldest_dirty_seq(yaffs_dev_t *dev)
+{
+	int i;
+	unsigned seq;
+	unsigned block_no = 0;
+	yaffs_block_info_t *b;
+
+	if(!dev->param.is_yaffs2)
+		return;
+
+	/* Find the oldest dirty sequence number. */
+	seq = dev->seq_number + 1;
+	b = dev->block_info;
+	for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
+		if (b->block_state == YAFFS_BLOCK_STATE_FULL &&
+			(b->pages_in_use - b->soft_del_pages) < dev->param.chunks_per_block &&
+			b->seq_number < seq) {
+			seq = b->seq_number;
+			block_no = i;
+		}
+		b++;
+	}
+
+	if(block_no){
+		dev->oldest_dirty_seq = seq;
+		dev->oldest_dirty_block = block_no;
+	}
+
+}
+
+
+void yaffs2_find_oldest_dirty_seq(yaffs_dev_t *dev)
+{
+	if(!dev->param.is_yaffs2)
+		return;
+
+	if(!dev->oldest_dirty_seq)
+		yaffs_calc_oldest_dirty_seq(dev);
+}
+
+/*
+ * yaffs_clear_oldest_dirty_seq()
+ * Called when a block is erased or marked bad. (ie. when its seq_number
+ * becomes invalid). If the value matches the oldest then we clear 
+ * dev->oldest_dirty_seq to force its recomputation.
+ */
+void yaffs2_clear_oldest_dirty_seq(yaffs_dev_t *dev, yaffs_block_info_t *bi)
+{
+
+	if(!dev->param.is_yaffs2)
+		return;
+
+	if(!bi || bi->seq_number == dev->oldest_dirty_seq){
+		dev->oldest_dirty_seq = 0;
+		dev->oldest_dirty_block = 0;
+	}
+}
+
+/*
+ * yaffs2_update_oldest_dirty_seq()
+ * Update the oldest dirty sequence number whenever we dirty a block.
+ * Only do this if the oldest_dirty_seq is actually being tracked.
+ */
+void yaffs2_update_oldest_dirty_seq(yaffs_dev_t *dev, unsigned block_no, yaffs_block_info_t *bi)
+{
+	if(!dev->param.is_yaffs2)
+		return;
+
+	if(dev->oldest_dirty_seq){
+		if(dev->oldest_dirty_seq > bi->seq_number){
+			dev->oldest_dirty_seq = bi->seq_number;
+			dev->oldest_dirty_block = block_no;
+		}
+	}
+}
+
+int yaffs_block_ok_for_gc(yaffs_dev_t *dev,
+					yaffs_block_info_t *bi)
+{
+
+	if (!dev->param.is_yaffs2)
+		return 1;	/* disqualification only applies to yaffs2. */
+
+	if (!bi->has_shrink_hdr)
+		return 1;	/* can gc */
+
+	yaffs2_find_oldest_dirty_seq(dev);
+
+	/* Can't do gc of this block if there are any blocks older than this one that have
+	 * discarded pages.
+	 */
+	return (bi->seq_number <= dev->oldest_dirty_seq);
+}
+
+/*
+ * yaffs2_find_refresh_block()
+ * periodically finds the oldest full block by sequence number for refreshing.
+ * Only for yaffs2.
+ */
+__u32 yaffs2_find_refresh_block(yaffs_dev_t *dev)
+{
+	__u32 b ;
+
+	__u32 oldest = 0;
+	__u32 oldest_seq = 0;
+
+	yaffs_block_info_t *bi;
+
+	if(!dev->param.is_yaffs2)
+		return oldest;
+
+	/*
+	 * If refresh period < 10 then refreshing is disabled.
+	 */
+	if(dev->param.refresh_period < 10)
+	        return oldest;
+
+        /*
+         * Fix broken values.
+         */
+        if(dev->refresh_skip > dev->param.refresh_period)
+                dev->refresh_skip = dev->param.refresh_period;
+
+	if(dev->refresh_skip > 0)
+	        return oldest;
+
+	/*
+	 * Refresh skip is now zero.
+	 * We'll do a refresh this time around....
+	 * Update the refresh skip and find the oldest block.
+	 */
+	dev->refresh_skip = dev->param.refresh_period;
+	dev->refresh_count++;
+	bi = dev->block_info;
+	for (b = dev->internal_start_block; b <=dev->internal_end_block; b++){
+
+		if (bi->block_state == YAFFS_BLOCK_STATE_FULL){
+
+			if(oldest < 1 ||
+                                bi->seq_number < oldest_seq){
+                                oldest = b;
+                                oldest_seq = bi->seq_number;
+                        }
+		}
+		bi++;
+	}
+
+	if (oldest > 0) {
+		T(YAFFS_TRACE_GC,
+		  (TSTR("GC refresh count %d selected block %d with seq_number %d" TENDSTR),
+		   dev->refresh_count, oldest, oldest_seq));
+	}
+
+	return oldest;
+}
+
+int yaffs2_checkpt_required(yaffs_dev_t *dev)
+{
+	int nblocks;
+	
+	if(!dev->param.is_yaffs2)
+		return 0;
+	
+	nblocks = dev->internal_end_block - dev->internal_start_block + 1 ;
+
+	return 	!dev->param.skip_checkpt_wr &&
+		!dev->read_only &&
+		(nblocks >= YAFFS_CHECKPOINT_MIN_BLOCKS);
+}
+
+int yaffs_calc_checkpt_blocks_required(yaffs_dev_t *dev)
+{
+	int retval;
+
+	if(!dev->param.is_yaffs2)
+		return 0;
+
+	if (!dev->checkpoint_blocks_required &&
+		yaffs2_checkpt_required(dev)){
+		/* Not a valid value so recalculate */
+		int n_bytes = 0;
+		int n_blocks;
+		int dev_blocks = (dev->param.end_block - dev->param.start_block + 1);
+
+		n_bytes += sizeof(yaffs_checkpt_validty_t);
+		n_bytes += sizeof(yaffs_checkpt_dev_t);
+		n_bytes += dev_blocks * sizeof(yaffs_block_info_t);
+		n_bytes += dev_blocks * dev->chunk_bit_stride;
+		n_bytes += (sizeof(yaffs_checkpt_obj_t) + sizeof(__u32)) * (dev->n_obj);
+		n_bytes += (dev->tnode_size + sizeof(__u32)) * (dev->n_tnodes);
+		n_bytes += sizeof(yaffs_checkpt_validty_t);
+		n_bytes += sizeof(__u32); /* checksum*/
+
+		/* Round up and add 2 blocks to allow for some bad blocks, so add 3 */
+
+		n_blocks = (n_bytes/(dev->data_bytes_per_chunk * dev->param.chunks_per_block)) + 3;
+
+		dev->checkpoint_blocks_required = n_blocks;
+	}
+
+	retval = dev->checkpoint_blocks_required - dev->blocks_in_checkpt;
+	if(retval < 0)
+		retval = 0;
+	return retval;
+}
+
+/*--------------------- Checkpointing --------------------*/
+
+
+static int yaffs2_wr_checkpt_validity_marker(yaffs_dev_t *dev, int head)
+{
+	yaffs_checkpt_validty_t cp;
+
+	memset(&cp, 0, sizeof(cp));
+
+	cp.struct_type = sizeof(cp);
+	cp.magic = YAFFS_MAGIC;
+	cp.version = YAFFS_CHECKPOINT_VERSION;
+	cp.head = (head) ? 1 : 0;
+
+	return (yaffs2_checkpt_wr(dev, &cp, sizeof(cp)) == sizeof(cp)) ?
+		1 : 0;
+}
+
+static int yaffs2_rd_checkpt_validty_marker(yaffs_dev_t *dev, int head)
+{
+	yaffs_checkpt_validty_t cp;
+	int ok;
+
+	ok = (yaffs2_checkpt_rd(dev, &cp, sizeof(cp)) == sizeof(cp));
+
+	if (ok)
+		ok = (cp.struct_type == sizeof(cp)) &&
+		     (cp.magic == YAFFS_MAGIC) &&
+		     (cp.version == YAFFS_CHECKPOINT_VERSION) &&
+		     (cp.head == ((head) ? 1 : 0));
+	return ok ? 1 : 0;
+}
+
+static void yaffs2_dev_to_checkpt_dev(yaffs_checkpt_dev_t *cp,
+					   yaffs_dev_t *dev)
+{
+	cp->n_erased_blocks = dev->n_erased_blocks;
+	cp->alloc_block = dev->alloc_block;
+	cp->alloc_page = dev->alloc_page;
+	cp->n_free_chunks = dev->n_free_chunks;
+
+	cp->n_deleted_files = dev->n_deleted_files;
+	cp->n_unlinked_files = dev->n_unlinked_files;
+	cp->n_bg_deletions = dev->n_bg_deletions;
+	cp->seq_number = dev->seq_number;
+
+}
+
+static void yaffs_checkpt_dev_to_dev(yaffs_dev_t *dev,
+					   yaffs_checkpt_dev_t *cp)
+{
+	dev->n_erased_blocks = cp->n_erased_blocks;
+	dev->alloc_block = cp->alloc_block;
+	dev->alloc_page = cp->alloc_page;
+	dev->n_free_chunks = cp->n_free_chunks;
+
+	dev->n_deleted_files = cp->n_deleted_files;
+	dev->n_unlinked_files = cp->n_unlinked_files;
+	dev->n_bg_deletions = cp->n_bg_deletions;
+	dev->seq_number = cp->seq_number;
+}
+
+
+static int yaffs2_wr_checkpt_dev(yaffs_dev_t *dev)
+{
+	yaffs_checkpt_dev_t cp;
+	__u32 n_bytes;
+	__u32 n_blocks = (dev->internal_end_block - dev->internal_start_block + 1);
+
+	int ok;
+
+	/* Write device runtime values*/
+	yaffs2_dev_to_checkpt_dev(&cp, dev);
+	cp.struct_type = sizeof(cp);
+
+	ok = (yaffs2_checkpt_wr(dev, &cp, sizeof(cp)) == sizeof(cp));
+
+	/* Write block info */
+	if (ok) {
+		n_bytes = n_blocks * sizeof(yaffs_block_info_t);
+		ok = (yaffs2_checkpt_wr(dev, dev->block_info, n_bytes) == n_bytes);
+	}
+
+	/* Write chunk bits */
+	if (ok) {
+		n_bytes = n_blocks * dev->chunk_bit_stride;
+		ok = (yaffs2_checkpt_wr(dev, dev->chunk_bits, n_bytes) == n_bytes);
+	}
+	return	 ok ? 1 : 0;
+
+}
+
+static int yaffs2_rd_checkpt_dev(yaffs_dev_t *dev)
+{
+	yaffs_checkpt_dev_t cp;
+	__u32 n_bytes;
+	__u32 n_blocks = (dev->internal_end_block - dev->internal_start_block + 1);
+
+	int ok;
+
+	ok = (yaffs2_checkpt_rd(dev, &cp, sizeof(cp)) == sizeof(cp));
+	if (!ok)
+		return 0;
+
+	if (cp.struct_type != sizeof(cp))
+		return 0;
+
+
+	yaffs_checkpt_dev_to_dev(dev, &cp);
+
+	n_bytes = n_blocks * sizeof(yaffs_block_info_t);
+
+	ok = (yaffs2_checkpt_rd(dev, dev->block_info, n_bytes) == n_bytes);
+
+	if (!ok)
+		return 0;
+	n_bytes = n_blocks * dev->chunk_bit_stride;
+
+	ok = (yaffs2_checkpt_rd(dev, dev->chunk_bits, n_bytes) == n_bytes);
+
+	return ok ? 1 : 0;
+}
+
+static void yaffs2_obj_checkpt_obj(yaffs_checkpt_obj_t *cp,
+					   yaffs_obj_t *obj)
+{
+
+	cp->obj_id = obj->obj_id;
+	cp->parent_id = (obj->parent) ? obj->parent->obj_id : 0;
+	cp->hdr_chunk = obj->hdr_chunk;
+	cp->variant_type = obj->variant_type;
+	cp->deleted = obj->deleted;
+	cp->soft_del = obj->soft_del;
+	cp->unlinked = obj->unlinked;
+	cp->fake = obj->fake;
+	cp->rename_allowed = obj->rename_allowed;
+	cp->unlink_allowed = obj->unlink_allowed;
+	cp->serial = obj->serial;
+	cp->n_data_chunks = obj->n_data_chunks;
+
+	if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE)
+		cp->size_or_equiv_obj = obj->variant.file_variant.file_size;
+	else if (obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK)
+		cp->size_or_equiv_obj = obj->variant.hardlink_variant.equiv_id;
+}
+
+static int taffs2_checkpt_obj_to_obj(yaffs_obj_t *obj, yaffs_checkpt_obj_t *cp)
+{
+
+	yaffs_obj_t *parent;
+
+	if (obj->variant_type != cp->variant_type) {
+		T(YAFFS_TRACE_ERROR, (TSTR("Checkpoint read object %d type %d "
+			TCONT("chunk %d does not match existing object type %d")
+			TENDSTR), cp->obj_id, cp->variant_type, cp->hdr_chunk,
+			obj->variant_type));
+		return 0;
+	}
+
+	obj->obj_id = cp->obj_id;
+
+	if (cp->parent_id)
+		parent = yaffs_find_or_create_by_number(
+					obj->my_dev,
+					cp->parent_id,
+					YAFFS_OBJECT_TYPE_DIRECTORY);
+	else
+		parent = NULL;
+
+	if (parent) {
+		if (parent->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
+			T(YAFFS_TRACE_ALWAYS, (TSTR("Checkpoint read object %d parent %d type %d"
+				TCONT(" chunk %d Parent type, %d, not directory")
+				TENDSTR),
+				cp->obj_id, cp->parent_id, cp->variant_type,
+				cp->hdr_chunk, parent->variant_type));
+			return 0;
+		}
+		yaffs_add_obj_to_dir(parent, obj);
+	}
+
+	obj->hdr_chunk = cp->hdr_chunk;
+	obj->variant_type = cp->variant_type;
+	obj->deleted = cp->deleted;
+	obj->soft_del = cp->soft_del;
+	obj->unlinked = cp->unlinked;
+	obj->fake = cp->fake;
+	obj->rename_allowed = cp->rename_allowed;
+	obj->unlink_allowed = cp->unlink_allowed;
+	obj->serial = cp->serial;
+	obj->n_data_chunks = cp->n_data_chunks;
+
+	if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE)
+		obj->variant.file_variant.file_size = cp->size_or_equiv_obj;
+	else if (obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK)
+		obj->variant.hardlink_variant.equiv_id = cp->size_or_equiv_obj;
+
+	if (obj->hdr_chunk > 0)
+		obj->lazy_loaded = 1;
+	return 1;
+}
+
+
+
+static int yaffs2_checkpt_tnode_worker(yaffs_obj_t *in, yaffs_tnode_t *tn,
+					__u32 level, int chunk_offset)
+{
+	int i;
+	yaffs_dev_t *dev = in->my_dev;
+	int ok = 1;
+
+	if (tn) {
+		if (level > 0) {
+
+			for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++) {
+				if (tn->internal[i]) {
+					ok = yaffs2_checkpt_tnode_worker(in,
+							tn->internal[i],
+							level - 1,
+							(chunk_offset<<YAFFS_TNODES_INTERNAL_BITS) + i);
+				}
+			}
+		} else if (level == 0) {
+			__u32 base_offset = chunk_offset <<  YAFFS_TNODES_LEVEL0_BITS;
+			ok = (yaffs2_checkpt_wr(dev, &base_offset, sizeof(base_offset)) == 
+			        sizeof(base_offset));
+			if (ok)
+				ok = (yaffs2_checkpt_wr(dev, tn, dev->tnode_size) == dev->tnode_size);
+		}
+	}
+
+	return ok;
+
+}
+
+static int yaffs2_wr_checkpt_tnodes(yaffs_obj_t *obj)
+{
+	__u32 end_marker = ~0;
+	int ok = 1;
+
+	if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE) {
+		ok = yaffs2_checkpt_tnode_worker(obj,
+					    obj->variant.file_variant.top,
+					    obj->variant.file_variant.top_level,
+					    0);
+		if (ok)
+			ok = (yaffs2_checkpt_wr(obj->my_dev, &end_marker, sizeof(end_marker)) ==
+				sizeof(end_marker));
+	}
+
+	return ok ? 1 : 0;
+}
+
+static int yaffs2_rd_checkpt_tnodes(yaffs_obj_t *obj)
+{
+	__u32 base_chunk;
+	int ok = 1;
+	yaffs_dev_t *dev = obj->my_dev;
+	yaffs_file_s *file_stuct_ptr = &obj->variant.file_variant;
+	yaffs_tnode_t *tn;
+	int nread = 0;
+
+	ok = (yaffs2_checkpt_rd(dev, &base_chunk, sizeof(base_chunk)) == sizeof(base_chunk));
+
+	while (ok && (~base_chunk)) {
+		nread++;
+		/* Read level 0 tnode */
+
+
+		tn = yaffs_get_tnode(dev);
+		if (tn){
+			ok = (yaffs2_checkpt_rd(dev, tn, dev->tnode_size) == dev->tnode_size);
+		} else
+			ok = 0;
+
+		if (tn && ok)
+			ok = yaffs_add_find_tnode_0(dev,
+							file_stuct_ptr,
+							base_chunk,
+							tn) ? 1 : 0;
+
+		if (ok)
+			ok = (yaffs2_checkpt_rd(dev, &base_chunk, sizeof(base_chunk)) == sizeof(base_chunk));
+
+	}
+
+	T(YAFFS_TRACE_CHECKPOINT, (
+		TSTR("Checkpoint read tnodes %d records, last %d. ok %d" TENDSTR),
+		nread, base_chunk, ok));
+
+	return ok ? 1 : 0;
+}
+
+
+static int yaffs2_wr_checkpt_objs(yaffs_dev_t *dev)
+{
+	yaffs_obj_t *obj;
+	yaffs_checkpt_obj_t cp;
+	int i;
+	int ok = 1;
+	struct ylist_head *lh;
+
+
+	/* Iterate through the objects in each hash entry,
+	 * dumping them to the checkpointing stream.
+	 */
+
+	for (i = 0; ok &&  i <  YAFFS_NOBJECT_BUCKETS; i++) {
+		ylist_for_each(lh, &dev->obj_bucket[i].list) {
+			if (lh) {
+				obj = ylist_entry(lh, yaffs_obj_t, hash_link);
+				if (!obj->defered_free) {
+					yaffs2_obj_checkpt_obj(&cp, obj);
+					cp.struct_type = sizeof(cp);
+
+					T(YAFFS_TRACE_CHECKPOINT, (
+						TSTR("Checkpoint write object %d parent %d type %d chunk %d obj addr %p" TENDSTR),
+						cp.obj_id, cp.parent_id, cp.variant_type, cp.hdr_chunk, obj));
+
+					ok = (yaffs2_checkpt_wr(dev, &cp, sizeof(cp)) == sizeof(cp));
+
+					if (ok && obj->variant_type == YAFFS_OBJECT_TYPE_FILE)
+						ok = yaffs2_wr_checkpt_tnodes(obj);
+				}
+			}
+		}
+	}
+
+	/* Dump end of list */
+	memset(&cp, 0xFF, sizeof(yaffs_checkpt_obj_t));
+	cp.struct_type = sizeof(cp);
+
+	if (ok)
+		ok = (yaffs2_checkpt_wr(dev, &cp, sizeof(cp)) == sizeof(cp));
+
+	return ok ? 1 : 0;
+}
+
+static int yaffs2_rd_checkpt_objs(yaffs_dev_t *dev)
+{
+	yaffs_obj_t *obj;
+	yaffs_checkpt_obj_t cp;
+	int ok = 1;
+	int done = 0;
+	yaffs_obj_t *hard_list = NULL;
+
+	while (ok && !done) {
+		ok = (yaffs2_checkpt_rd(dev, &cp, sizeof(cp)) == sizeof(cp));
+		if (cp.struct_type != sizeof(cp)) {
+			T(YAFFS_TRACE_CHECKPOINT, (TSTR("struct size %d instead of %d ok %d"TENDSTR),
+				cp.struct_type, (int)sizeof(cp), ok));
+			ok = 0;
+		}
+
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("Checkpoint read object %d parent %d type %d chunk %d " TENDSTR),
+			cp.obj_id, cp.parent_id, cp.variant_type, cp.hdr_chunk));
+
+		if (ok && cp.obj_id == ~0)
+			done = 1;
+		else if (ok) {
+			obj = yaffs_find_or_create_by_number(dev, cp.obj_id, cp.variant_type);
+			if (obj) {
+				ok = taffs2_checkpt_obj_to_obj(obj, &cp);
+				if (!ok)
+					break;
+				if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE) {
+					ok = yaffs2_rd_checkpt_tnodes(obj);
+				} else if (obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) {
+					obj->hard_links.next =
+						(struct ylist_head *) hard_list;
+					hard_list = obj;
+				}
+			} else
+				ok = 0;
+		}
+	}
+
+	if (ok)
+		yaffs_link_fixup(dev, hard_list);
+
+	return ok ? 1 : 0;
+}
+
+static int yaffs2_wr_checkpt_sum(yaffs_dev_t *dev)
+{
+	__u32 checkpt_sum;
+	int ok;
+
+	yaffs2_get_checkpt_sum(dev, &checkpt_sum);
+
+	ok = (yaffs2_checkpt_wr(dev, &checkpt_sum, sizeof(checkpt_sum)) == sizeof(checkpt_sum));
+
+	if (!ok)
+		return 0;
+
+	return 1;
+}
+
+static int yaffs2_rd_checkpt_sum(yaffs_dev_t *dev)
+{
+	__u32 checkpt_sum0;
+	__u32 checkpt_sum1;
+	int ok;
+
+	yaffs2_get_checkpt_sum(dev, &checkpt_sum0);
+
+	ok = (yaffs2_checkpt_rd(dev, &checkpt_sum1, sizeof(checkpt_sum1)) == sizeof(checkpt_sum1));
+
+	if (!ok)
+		return 0;
+
+	if (checkpt_sum0 != checkpt_sum1)
+		return 0;
+
+	return 1;
+}
+
+
+static int yaffs2_wr_checkpt_data(yaffs_dev_t *dev)
+{
+	int ok = 1;
+
+	if (!yaffs2_checkpt_required(dev)) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("skipping checkpoint write" TENDSTR)));
+		ok = 0;
+	}
+
+	if (ok)
+		ok = yaffs2_checkpt_open(dev, 1);
+
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("write checkpoint validity" TENDSTR)));
+		ok = yaffs2_wr_checkpt_validity_marker(dev, 1);
+	}
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("write checkpoint device" TENDSTR)));
+		ok = yaffs2_wr_checkpt_dev(dev);
+	}
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("write checkpoint objects" TENDSTR)));
+		ok = yaffs2_wr_checkpt_objs(dev);
+	}
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("write checkpoint validity" TENDSTR)));
+		ok = yaffs2_wr_checkpt_validity_marker(dev, 0);
+	}
+
+	if (ok)
+		ok = yaffs2_wr_checkpt_sum(dev);
+
+	if (!yaffs_checkpt_close(dev))
+		ok = 0;
+
+	if (ok)
+		dev->is_checkpointed = 1;
+	else
+		dev->is_checkpointed = 0;
+
+	return dev->is_checkpointed;
+}
+
+static int yaffs2_rd_checkpt_data(yaffs_dev_t *dev)
+{
+	int ok = 1;
+	
+	if(!dev->param.is_yaffs2)
+		ok = 0;
+
+	if (ok && dev->param.skip_checkpt_rd) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("skipping checkpoint read" TENDSTR)));
+		ok = 0;
+	}
+
+	if (ok)
+		ok = yaffs2_checkpt_open(dev, 0); /* open for read */
+
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("read checkpoint validity" TENDSTR)));
+		ok = yaffs2_rd_checkpt_validty_marker(dev, 1);
+	}
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("read checkpoint device" TENDSTR)));
+		ok = yaffs2_rd_checkpt_dev(dev);
+	}
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("read checkpoint objects" TENDSTR)));
+		ok = yaffs2_rd_checkpt_objs(dev);
+	}
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("read checkpoint validity" TENDSTR)));
+		ok = yaffs2_rd_checkpt_validty_marker(dev, 0);
+	}
+
+	if (ok) {
+		ok = yaffs2_rd_checkpt_sum(dev);
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("read checkpoint checksum %d" TENDSTR), ok));
+	}
+
+	if (!yaffs_checkpt_close(dev))
+		ok = 0;
+
+	if (ok)
+		dev->is_checkpointed = 1;
+	else
+		dev->is_checkpointed = 0;
+
+	return ok ? 1 : 0;
+
+}
+
+void yaffs2_checkpt_invalidate(yaffs_dev_t *dev)
+{
+	if (dev->is_checkpointed ||
+			dev->blocks_in_checkpt > 0) {
+		dev->is_checkpointed = 0;
+		yaffs2_checkpt_invalidate_stream(dev);
+	}
+	if (dev->param.sb_dirty_fn)
+		dev->param.sb_dirty_fn(dev);
+}
+
+
+int yaffs_checkpoint_save(yaffs_dev_t *dev)
+{
+
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("save entry: is_checkpointed %d"TENDSTR), dev->is_checkpointed));
+
+	yaffs_verify_objects(dev);
+	yaffs_verify_blocks(dev);
+	yaffs_verify_free_chunks(dev);
+
+	if (!dev->is_checkpointed) {
+		yaffs2_checkpt_invalidate(dev);
+		yaffs2_wr_checkpt_data(dev);
+	}
+
+	T(YAFFS_TRACE_ALWAYS, (TSTR("save exit: is_checkpointed %d"TENDSTR), dev->is_checkpointed));
+
+	return dev->is_checkpointed;
+}
+
+int yaffs2_checkpt_restore(yaffs_dev_t *dev)
+{
+	int retval;
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("restore entry: is_checkpointed %d"TENDSTR), dev->is_checkpointed));
+
+	retval = yaffs2_rd_checkpt_data(dev);
+
+	if (dev->is_checkpointed) {
+		yaffs_verify_objects(dev);
+		yaffs_verify_blocks(dev);
+		yaffs_verify_free_chunks(dev);
+	}
+
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("restore exit: is_checkpointed %d"TENDSTR), dev->is_checkpointed));
+
+	return retval;
+}
+
+int yaffs2_handle_hole(yaffs_obj_t *obj, loff_t new_size)
+{
+	/* if new_size > old_file_size.
+	 * We're going to be writing a hole.
+	 * If the hole is small then write zeros otherwise write a start of hole marker.
+	 */
+		
+
+	loff_t old_file_size;
+	int increase;
+	int small_hole   ;
+	int result = YAFFS_OK;
+	yaffs_dev_t *dev = NULL;
+
+	__u8 *local_buffer = NULL;
+	
+	int small_increase_ok = 0;
+	
+	if(!obj)
+		return YAFFS_FAIL;
+
+	if(obj->variant_type != YAFFS_OBJECT_TYPE_FILE)
+		return YAFFS_FAIL;
+	
+	dev = obj->my_dev;
+	
+	/* Bail out if not yaffs2 mode */
+	if(!dev->param.is_yaffs2)
+		return YAFFS_OK;
+
+	old_file_size = obj->variant.file_variant.file_size;
+
+	if (new_size <= old_file_size)
+		return YAFFS_OK;
+
+	increase = new_size - old_file_size;
+
+	if(increase < YAFFS_SMALL_HOLE_THRESHOLD * dev->data_bytes_per_chunk &&
+		yaffs_check_alloc_available(dev, YAFFS_SMALL_HOLE_THRESHOLD + 1))
+		small_hole = 1;
+	else
+		small_hole = 0;
+
+	if(small_hole)
+		local_buffer= yaffs_get_temp_buffer(dev, __LINE__);
+	
+	if(local_buffer){
+		/* fill hole with zero bytes */
+		int pos = old_file_size;
+		int this_write;
+		int written;
+		memset(local_buffer,0,dev->data_bytes_per_chunk);
+		small_increase_ok = 1;
+
+		while(increase > 0 && small_increase_ok){
+			this_write = increase;
+			if(this_write > dev->data_bytes_per_chunk)
+				this_write = dev->data_bytes_per_chunk;
+			written = yaffs_do_file_wr(obj,local_buffer,pos,this_write,0);
+			if(written == this_write){
+				pos += this_write;
+				increase -= this_write;
+			} else
+				small_increase_ok = 0;
+		}
+
+		yaffs_release_temp_buffer(dev,local_buffer,__LINE__);
+
+		/* If we were out of space then reverse any chunks we've added */		
+		if(!small_increase_ok)
+			yaffs_resize_file_down(obj, old_file_size);
+	}
+	
+	if (!small_increase_ok &&
+		obj->parent &&
+		obj->parent->obj_id != YAFFS_OBJECTID_UNLINKED &&
+		obj->parent->obj_id != YAFFS_OBJECTID_DELETED){
+		/* Write a hole start header with the old file size */
+		yaffs_update_oh(obj, NULL, 0, 1, 0, NULL);
+	}
+
+	return result;
+
+}
+
+
+typedef struct {
+	int seq;
+	int block;
+} yaffs_block_index;
+
+
+static int yaffs2_ybicmp(const void *a, const void *b)
+{
+	register int aseq = ((yaffs_block_index *)a)->seq;
+	register int bseq = ((yaffs_block_index *)b)->seq;
+	register int ablock = ((yaffs_block_index *)a)->block;
+	register int bblock = ((yaffs_block_index *)b)->block;
+	if (aseq == bseq)
+		return ablock - bblock;
+	else
+		return aseq - bseq;
+}
+
+int yaffs2_scan_backwards(yaffs_dev_t *dev)
+{
+	yaffs_ext_tags tags;
+	int blk;
+	int block_iter;
+	int start_iter;
+	int end_iter;
+	int n_to_scan = 0;
+
+	int chunk;
+	int result;
+	int c;
+	int deleted;
+	yaffs_block_state_t state;
+	yaffs_obj_t *hard_list = NULL;
+	yaffs_block_info_t *bi;
+	__u32 seq_number;
+	yaffs_obj_header *oh;
+	yaffs_obj_t *in;
+	yaffs_obj_t *parent;
+	int n_blocks = dev->internal_end_block - dev->internal_start_block + 1;
+	int is_unlinked;
+	__u8 *chunk_data;
+
+	int file_size;
+	int is_shrink;
+	int found_chunks;
+	int equiv_id;
+	int alloc_failed = 0;
+
+
+	yaffs_block_index *block_index = NULL;
+	int alt_block_index = 0;
+
+	T(YAFFS_TRACE_SCAN,
+	  (TSTR
+	   ("yaffs2_scan_backwards starts  intstartblk %d intendblk %d..."
+	    TENDSTR), dev->internal_start_block, dev->internal_end_block));
+
+
+	dev->seq_number = YAFFS_LOWEST_SEQUENCE_NUMBER;
+
+	block_index = YMALLOC(n_blocks * sizeof(yaffs_block_index));
+
+	if (!block_index) {
+		block_index = YMALLOC_ALT(n_blocks * sizeof(yaffs_block_index));
+		alt_block_index = 1;
+	}
+
+	if (!block_index) {
+		T(YAFFS_TRACE_SCAN,
+		  (TSTR("yaffs2_scan_backwards() could not allocate block index!" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	dev->blocks_in_checkpt = 0;
+
+	chunk_data = yaffs_get_temp_buffer(dev, __LINE__);
+
+	/* Scan all the blocks to determine their state */
+	bi = dev->block_info;
+	for (blk = dev->internal_start_block; blk <= dev->internal_end_block; blk++) {
+		yaffs_clear_chunk_bits(dev, blk);
+		bi->pages_in_use = 0;
+		bi->soft_del_pages = 0;
+
+		yaffs_query_init_block_state(dev, blk, &state, &seq_number);
+
+		bi->block_state = state;
+		bi->seq_number = seq_number;
+
+		if (bi->seq_number == YAFFS_SEQUENCE_CHECKPOINT_DATA)
+			bi->block_state = state = YAFFS_BLOCK_STATE_CHECKPOINT;
+		if (bi->seq_number == YAFFS_SEQUENCE_BAD_BLOCK)
+			bi->block_state = state = YAFFS_BLOCK_STATE_DEAD;
+
+		T(YAFFS_TRACE_SCAN_DEBUG,
+		  (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
+		   state, seq_number));
+
+
+		if (state == YAFFS_BLOCK_STATE_CHECKPOINT) {
+			dev->blocks_in_checkpt++;
+
+		} else if (state == YAFFS_BLOCK_STATE_DEAD) {
+			T(YAFFS_TRACE_BAD_BLOCKS,
+			  (TSTR("block %d is bad" TENDSTR), blk));
+		} else if (state == YAFFS_BLOCK_STATE_EMPTY) {
+			T(YAFFS_TRACE_SCAN_DEBUG,
+			  (TSTR("Block empty " TENDSTR)));
+			dev->n_erased_blocks++;
+			dev->n_free_chunks += dev->param.chunks_per_block;
+		} else if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
+
+			/* Determine the highest sequence number */
+			if (seq_number >= YAFFS_LOWEST_SEQUENCE_NUMBER &&
+			    seq_number < YAFFS_HIGHEST_SEQUENCE_NUMBER) {
+
+				block_index[n_to_scan].seq = seq_number;
+				block_index[n_to_scan].block = blk;
+
+				n_to_scan++;
+
+				if (seq_number >= dev->seq_number)
+					dev->seq_number = seq_number;
+			} else {
+				/* TODO: Nasty sequence number! */
+				T(YAFFS_TRACE_SCAN,
+				  (TSTR
+				   ("Block scanning block %d has bad sequence number %d"
+				    TENDSTR), blk, seq_number));
+
+			}
+		}
+		bi++;
+	}
+
+	T(YAFFS_TRACE_SCAN,
+	(TSTR("%d blocks to be sorted..." TENDSTR), n_to_scan));
+
+
+
+	YYIELD();
+
+	/* Sort the blocks by sequence number*/
+	yaffs_qsort(block_index, n_to_scan, sizeof(yaffs_block_index), yaffs2_ybicmp);
+
+	YYIELD();
+
+	T(YAFFS_TRACE_SCAN, (TSTR("...done" TENDSTR)));
+
+	/* Now scan the blocks looking at the data. */
+	start_iter = 0;
+	end_iter = n_to_scan - 1;
+	T(YAFFS_TRACE_SCAN_DEBUG,
+	  (TSTR("%d blocks to be scanned" TENDSTR), n_to_scan));
+
+	/* For each block.... backwards */
+	for (block_iter = end_iter; !alloc_failed && block_iter >= start_iter;
+			block_iter--) {
+		/* Cooperative multitasking! This loop can run for so
+		   long that watchdog timers expire. */
+		YYIELD();
+
+		/* get the block to scan in the correct order */
+		blk = block_index[block_iter].block;
+
+		bi = yaffs_get_block_info(dev, blk);
+
+
+		state = bi->block_state;
+
+		deleted = 0;
+
+		/* For each chunk in each block that needs scanning.... */
+		found_chunks = 0;
+		for (c = dev->param.chunks_per_block - 1;
+		     !alloc_failed && c >= 0 &&
+		     (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
+		      state == YAFFS_BLOCK_STATE_ALLOCATING); c--) {
+			/* Scan backwards...
+			 * Read the tags and decide what to do
+			 */
+
+			chunk = blk * dev->param.chunks_per_block + c;
+
+			result = yaffs_rd_chunk_tags_nand(dev, chunk, NULL,
+							&tags);
+
+			/* Let's have a good look at this chunk... */
+
+			if (!tags.chunk_used) {
+				/* An unassigned chunk in the block.
+				 * If there are used chunks after this one, then
+				 * it is a chunk that was skipped due to failing the erased
+				 * check. Just skip it so that it can be deleted.
+				 * But, more typically, We get here when this is an unallocated
+				 * chunk and his means that either the block is empty or
+				 * this is the one being allocated from
+				 */
+
+				if (found_chunks) {
+					/* This is a chunk that was skipped due to failing the erased check */
+				} else if (c == 0) {
+					/* We're looking at the first chunk in the block so the block is unused */
+					state = YAFFS_BLOCK_STATE_EMPTY;
+					dev->n_erased_blocks++;
+				} else {
+					if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
+					    state == YAFFS_BLOCK_STATE_ALLOCATING) {
+						if (dev->seq_number == bi->seq_number) {
+							/* this is the block being allocated from */
+
+							T(YAFFS_TRACE_SCAN,
+							  (TSTR
+							   (" Allocating from %d %d"
+							    TENDSTR), blk, c));
+
+							state = YAFFS_BLOCK_STATE_ALLOCATING;
+							dev->alloc_block = blk;
+							dev->alloc_page = c;
+							dev->alloc_block_finder = blk;
+						} else {
+							/* This is a partially written block that is not
+							 * the current allocation block.
+							 */
+
+							 T(YAFFS_TRACE_SCAN,
+							 (TSTR("Partially written block %d detected" TENDSTR),
+							 blk));
+						}
+					}
+				}
+
+				dev->n_free_chunks++;
+
+			} else if (tags.ecc_result == YAFFS_ECC_RESULT_UNFIXED) {
+				T(YAFFS_TRACE_SCAN,
+				  (TSTR(" Unfixed ECC in chunk(%d:%d), chunk ignored"TENDSTR),
+				  blk, c));
+
+				  dev->n_free_chunks++;
+
+			} else if (tags.obj_id > YAFFS_MAX_OBJECT_ID ||
+				tags.chunk_id > YAFFS_MAX_CHUNK_ID ||
+				(tags.chunk_id > 0 && tags.n_bytes > dev->data_bytes_per_chunk) ||
+				tags.seq_number != bi->seq_number ) {
+				T(YAFFS_TRACE_SCAN,
+				  (TSTR("Chunk (%d:%d) with bad tags:obj = %d, chunk_id = %d, n_bytes = %d, ignored"TENDSTR),
+				  blk, c,tags.obj_id, tags.chunk_id, tags.n_bytes));
+
+				  dev->n_free_chunks++;
+
+			} else if (tags.chunk_id > 0) {
+				/* chunk_id > 0 so it is a data chunk... */
+				unsigned int endpos;
+				__u32 chunk_base =
+				    (tags.chunk_id - 1) * dev->data_bytes_per_chunk;
+
+				found_chunks = 1;
+
+
+				yaffs_set_chunk_bit(dev, blk, c);
+				bi->pages_in_use++;
+
+				in = yaffs_find_or_create_by_number(dev,
+								      tags.
+								      obj_id,
+								      YAFFS_OBJECT_TYPE_FILE);
+				if (!in) {
+					/* Out of memory */
+					alloc_failed = 1;
+				}
+
+				if (in &&
+				    in->variant_type == YAFFS_OBJECT_TYPE_FILE
+				    && chunk_base < in->variant.file_variant.shrink_size) {
+					/* This has not been invalidated by a resize */
+					if (!yaffs_put_chunk_in_file(in, tags.chunk_id, chunk, -1)) {
+						alloc_failed = 1;
+					}
+
+					/* File size is calculated by looking at the data chunks if we have not
+					 * seen an object header yet. Stop this practice once we find an object header.
+					 */
+					endpos = chunk_base + tags.n_bytes;
+
+					if (!in->valid &&	/* have not got an object header yet */
+					    in->variant.file_variant.scanned_size < endpos) {
+						in->variant.file_variant.scanned_size = endpos;
+						in->variant.file_variant.file_size = endpos;
+					}
+
+				} else if (in) {
+					/* This chunk has been invalidated by a resize, or a past file deletion
+					 * so delete the chunk*/
+					yaffs_chunk_del(dev, chunk, 1, __LINE__);
+
+				}
+			} else {
+				/* chunk_id == 0, so it is an ObjectHeader.
+				 * Thus, we read in the object header and make the object
+				 */
+				found_chunks = 1;
+
+				yaffs_set_chunk_bit(dev, blk, c);
+				bi->pages_in_use++;
+
+				oh = NULL;
+				in = NULL;
+
+				if (tags.extra_available) {
+					in = yaffs_find_or_create_by_number(dev,
+						tags.obj_id,
+						tags.extra_obj_type);
+					if (!in)
+						alloc_failed = 1;
+				}
+
+				if (!in ||
+				    (!in->valid && dev->param.disable_lazy_load) ||
+				    tags.extra_shadows ||
+				    (!in->valid &&
+				    (tags.obj_id == YAFFS_OBJECTID_ROOT ||
+				     tags.obj_id == YAFFS_OBJECTID_LOSTNFOUND))) {
+
+					/* If we don't have  valid info then we need to read the chunk
+					 * TODO In future we can probably defer reading the chunk and
+					 * living with invalid data until needed.
+					 */
+
+					result = yaffs_rd_chunk_tags_nand(dev,
+									chunk,
+									chunk_data,
+									NULL);
+
+					oh = (yaffs_obj_header *) chunk_data;
+
+					if (dev->param.inband_tags) {
+						/* Fix up the header if they got corrupted by inband tags */
+						oh->shadows_obj = oh->inband_shadowed_obj_id;
+						oh->is_shrink = oh->inband_is_shrink;
+					}
+
+					if (!in) {
+						in = yaffs_find_or_create_by_number(dev, tags.obj_id, oh->type);
+						if (!in)
+							alloc_failed = 1;
+					}
+
+				}
+
+				if (!in) {
+					/* TODO Hoosterman we have a problem! */
+					T(YAFFS_TRACE_ERROR,
+					  (TSTR
+					   ("yaffs tragedy: Could not make object for object  %d at chunk %d during scan"
+					    TENDSTR), tags.obj_id, chunk));
+					continue;
+				}
+
+				if (in->valid) {
+					/* We have already filled this one.
+					 * We have a duplicate that will be discarded, but
+					 * we first have to suck out resize info if it is a file.
+					 */
+
+					if ((in->variant_type == YAFFS_OBJECT_TYPE_FILE) &&
+					     ((oh &&
+					       oh->type == YAFFS_OBJECT_TYPE_FILE) ||
+					      (tags.extra_available  &&
+					       tags.extra_obj_type == YAFFS_OBJECT_TYPE_FILE))) {
+						__u32 this_size =
+						    (oh) ? oh->file_size : tags.
+						    extra_length;
+						__u32 parent_obj_id =
+						    (oh) ? oh->
+						    parent_obj_id : tags.
+						    extra_parent_id;
+
+
+						is_shrink =
+						    (oh) ? oh->is_shrink : tags.
+						    extra_is_shrink;
+
+						/* If it is deleted (unlinked at start also means deleted)
+						 * we treat the file size as being zeroed at this point.
+						 */
+						if (parent_obj_id ==
+						    YAFFS_OBJECTID_DELETED
+						    || parent_obj_id ==
+						    YAFFS_OBJECTID_UNLINKED) {
+							this_size = 0;
+							is_shrink = 1;
+						}
+
+						if (is_shrink && in->variant.file_variant.shrink_size > this_size)
+							in->variant.file_variant.shrink_size = this_size;
+
+						if (is_shrink)
+							bi->has_shrink_hdr = 1;
+
+					}
+					/* Use existing - destroy this one. */
+					yaffs_chunk_del(dev, chunk, 1, __LINE__);
+
+				}
+
+				if (!in->valid && in->variant_type !=
+				    (oh ? oh->type : tags.extra_obj_type))
+					T(YAFFS_TRACE_ERROR, (
+						TSTR("yaffs tragedy: Bad object type, "
+					    TCONT("%d != %d, for object %d at chunk ")
+					    TCONT("%d during scan")
+						TENDSTR), oh ?
+					    oh->type : tags.extra_obj_type,
+					    in->variant_type, tags.obj_id,
+					    chunk));
+
+				if (!in->valid &&
+				    (tags.obj_id == YAFFS_OBJECTID_ROOT ||
+				     tags.obj_id ==
+				     YAFFS_OBJECTID_LOSTNFOUND)) {
+					/* We only load some info, don't fiddle with directory structure */
+					in->valid = 1;
+
+					if (oh) {
+
+						in->yst_mode = oh->yst_mode;
+#ifdef CONFIG_YAFFS_WINCE
+						in->win_atime[0] = oh->win_atime[0];
+						in->win_ctime[0] = oh->win_ctime[0];
+						in->win_mtime[0] = oh->win_mtime[0];
+						in->win_atime[1] = oh->win_atime[1];
+						in->win_ctime[1] = oh->win_ctime[1];
+						in->win_mtime[1] = oh->win_mtime[1];
+#else
+						in->yst_uid = oh->yst_uid;
+						in->yst_gid = oh->yst_gid;
+						in->yst_atime = oh->yst_atime;
+						in->yst_mtime = oh->yst_mtime;
+						in->yst_ctime = oh->yst_ctime;
+						in->yst_rdev = oh->yst_rdev;
+
+						in->lazy_loaded = 0;
+
+#endif
+					} else
+						in->lazy_loaded = 1;
+
+					in->hdr_chunk = chunk;
+
+				} else if (!in->valid) {
+					/* we need to load this info */
+
+					in->valid = 1;
+					in->hdr_chunk = chunk;
+
+					if (oh) {
+						in->variant_type = oh->type;
+
+						in->yst_mode = oh->yst_mode;
+#ifdef CONFIG_YAFFS_WINCE
+						in->win_atime[0] = oh->win_atime[0];
+						in->win_ctime[0] = oh->win_ctime[0];
+						in->win_mtime[0] = oh->win_mtime[0];
+						in->win_atime[1] = oh->win_atime[1];
+						in->win_ctime[1] = oh->win_ctime[1];
+						in->win_mtime[1] = oh->win_mtime[1];
+#else
+						in->yst_uid = oh->yst_uid;
+						in->yst_gid = oh->yst_gid;
+						in->yst_atime = oh->yst_atime;
+						in->yst_mtime = oh->yst_mtime;
+						in->yst_ctime = oh->yst_ctime;
+						in->yst_rdev = oh->yst_rdev;
+#endif
+
+						if (oh->shadows_obj > 0)
+							yaffs_handle_shadowed_obj(dev,
+									   oh->
+									   shadows_obj,
+									   1);
+							
+
+
+						yaffs_set_obj_name_from_oh(in, oh);
+						parent =
+						    yaffs_find_or_create_by_number
+							(dev, oh->parent_obj_id,
+							 YAFFS_OBJECT_TYPE_DIRECTORY);
+
+						 file_size = oh->file_size;
+						 is_shrink = oh->is_shrink;
+						 equiv_id = oh->equiv_id;
+
+					} else {
+						in->variant_type = tags.extra_obj_type;
+						parent =
+						    yaffs_find_or_create_by_number
+							(dev, tags.extra_parent_id,
+							 YAFFS_OBJECT_TYPE_DIRECTORY);
+						 file_size = tags.extra_length;
+						 is_shrink = tags.extra_is_shrink;
+						 equiv_id = tags.extra_equiv_id;
+						in->lazy_loaded = 1;
+
+					}
+					in->dirty = 0;
+
+					if (!parent)
+						alloc_failed = 1;
+
+					/* directory stuff...
+					 * hook up to parent
+					 */
+
+					if (parent && parent->variant_type ==
+					    YAFFS_OBJECT_TYPE_UNKNOWN) {
+						/* Set up as a directory */
+						parent->variant_type =
+							YAFFS_OBJECT_TYPE_DIRECTORY;
+						YINIT_LIST_HEAD(&parent->variant.
+							dir_variant.
+							children);
+					} else if (!parent || parent->variant_type !=
+						   YAFFS_OBJECT_TYPE_DIRECTORY) {
+						/* Hoosterman, another problem....
+						 * We're trying to use a non-directory as a directory
+						 */
+
+						T(YAFFS_TRACE_ERROR,
+						  (TSTR
+						   ("yaffs tragedy: attempting to use non-directory as a directory in scan. Put in lost+found."
+						    TENDSTR)));
+						parent = dev->lost_n_found;
+					}
+
+					yaffs_add_obj_to_dir(parent, in);
+
+					is_unlinked = (parent == dev->del_dir) ||
+						      (parent == dev->unlinked_dir);
+
+					if (is_shrink) {
+						/* Mark the block as having a shrink header */
+						bi->has_shrink_hdr = 1;
+					}
+
+					/* Note re hardlinks.
+					 * Since we might scan a hardlink before its equivalent object is scanned
+					 * we put them all in a list.
+					 * After scanning is complete, we should have all the objects, so we run
+					 * through this list and fix up all the chains.
+					 */
+
+					switch (in->variant_type) {
+					case YAFFS_OBJECT_TYPE_UNKNOWN:
+						/* Todo got a problem */
+						break;
+					case YAFFS_OBJECT_TYPE_FILE:
+
+						if (in->variant.file_variant.
+						    scanned_size < file_size) {
+							/* This covers the case where the file size is greater
+							 * than where the data is
+							 * This will happen if the file is resized to be larger
+							 * than its current data extents.
+							 */
+							in->variant.file_variant.file_size = file_size;
+							in->variant.file_variant.scanned_size = file_size;
+						}
+
+						if (in->variant.file_variant.shrink_size > file_size)
+							in->variant.file_variant.shrink_size = file_size;
+				
+
+						break;
+					case YAFFS_OBJECT_TYPE_HARDLINK:
+						if (!is_unlinked) {
+							in->variant.hardlink_variant.equiv_id =
+								equiv_id;
+							in->hard_links.next =
+								(struct ylist_head *) hard_list;
+							hard_list = in;
+						}
+						break;
+					case YAFFS_OBJECT_TYPE_DIRECTORY:
+						/* Do nothing */
+						break;
+					case YAFFS_OBJECT_TYPE_SPECIAL:
+						/* Do nothing */
+						break;
+					case YAFFS_OBJECT_TYPE_SYMLINK:
+						if (oh) {
+							in->variant.symlink_variant.alias =
+								yaffs_clone_str(oh->alias);
+							if (!in->variant.symlink_variant.alias)
+								alloc_failed = 1;
+						}
+						break;
+					}
+
+				}
+
+			}
+
+		} /* End of scanning for each chunk */
+
+		if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
+			/* If we got this far while scanning, then the block is fully allocated. */
+			state = YAFFS_BLOCK_STATE_FULL;
+		}
+
+
+		bi->block_state = state;
+
+		/* Now let's see if it was dirty */
+		if (bi->pages_in_use == 0 &&
+		    !bi->has_shrink_hdr &&
+		    bi->block_state == YAFFS_BLOCK_STATE_FULL) {
+			yaffs_block_became_dirty(dev, blk);
+		}
+
+	}
+	
+	yaffs_skip_rest_of_block(dev);
+
+	if (alt_block_index)
+		YFREE_ALT(block_index);
+	else
+		YFREE(block_index);
+
+	/* Ok, we've done all the scanning.
+	 * Fix up the hard link chains.
+	 * We should now have scanned all the objects, now it's time to add these
+	 * hardlinks.
+	 */
+	yaffs_link_fixup(dev, hard_list);
+
+
+	yaffs_release_temp_buffer(dev, chunk_data, __LINE__);
+
+	if (alloc_failed)
+		return YAFFS_FAIL;
+
+	T(YAFFS_TRACE_SCAN, (TSTR("yaffs2_scan_backwards ends" TENDSTR)));
+
+	return YAFFS_OK;
+}
diff --git a/drivers/staging/yaffs2/yaffs_yaffs2.h b/drivers/staging/yaffs2/yaffs_yaffs2.h
new file mode 100644
index 0000000..ce1fa9d
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_yaffs2.h
@@ -0,0 +1,38 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_YAFFS2_H__
+#define __YAFFS_YAFFS2_H__
+
+#include "yaffs_guts.h"
+
+void yaffs_calc_oldest_dirty_seq(yaffs_dev_t *dev);
+void yaffs2_find_oldest_dirty_seq(yaffs_dev_t *dev);
+void yaffs2_clear_oldest_dirty_seq(yaffs_dev_t *dev, yaffs_block_info_t *bi);
+void yaffs2_update_oldest_dirty_seq(yaffs_dev_t *dev, unsigned block_no, yaffs_block_info_t *bi);
+int yaffs_block_ok_for_gc(yaffs_dev_t *dev, yaffs_block_info_t *bi);
+__u32 yaffs2_find_refresh_block(yaffs_dev_t *dev);
+int yaffs2_checkpt_required(yaffs_dev_t *dev);
+int yaffs_calc_checkpt_blocks_required(yaffs_dev_t *dev);
+
+
+void yaffs2_checkpt_invalidate(yaffs_dev_t *dev);
+int yaffs2_checkpt_save(yaffs_dev_t *dev);
+int yaffs2_checkpt_restore(yaffs_dev_t *dev);
+
+int yaffs2_handle_hole(yaffs_obj_t *obj, loff_t new_size);
+int yaffs2_scan_backwards(yaffs_dev_t *dev);
+
+#endif
-- 
1.7.3.2.146.gca209

[PATCH 28/29] Staging: yaffs2: yportenv.h: Add file

[Tracey Dent]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yportenv.h |  333 +++++++++++++++++++++++++++++++++++++
 1 files changed, 333 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yportenv.h

diff --git a/drivers/staging/yaffs2/yportenv.h b/drivers/staging/yaffs2/yportenv.h
new file mode 100644
index 0000000..2f9063b
--- /dev/null
+++ b/drivers/staging/yaffs2/yportenv.h
@@ -0,0 +1,333 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+
+#ifndef __YPORTENV_H__
+#define __YPORTENV_H__
+
+/*
+ * Define the MTD version in terms of Linux Kernel versions
+ * This allows yaffs to be used independantly of the kernel
+ * as well as with it.
+ */
+
+#define MTD_VERSION(a, b, c) (((a) << 16) + ((b) << 8) + (c))
+
+#if defined CONFIG_YAFFS_WINCE
+
+#include "ywinceenv.h"
+
+#elif defined __KERNEL__
+
+#include "moduleconfig.h"
+
+/* Linux kernel */
+
+#include <linux/version.h>
+#define MTD_VERSION_CODE LINUX_VERSION_CODE
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 19))
+#include <linux/config.h>
+#endif
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/xattr.h>
+
+#define YCHAR char
+#define YUCHAR unsigned char
+#define _Y(x)     x
+#define yaffs_strcat(a, b)     strcat(a, b)
+#define yaffs_strcpy(a, b)     strcpy(a, b)
+#define yaffs_strncpy(a, b, c) strncpy(a, b, c)
+#define yaffs_strncmp(a, b, c) strncmp(a, b, c)
+#define yaffs_strnlen(s,m)	strnlen(s,m)
+#define yaffs_sprintf	       sprintf
+#define yaffs_toupper(a)       toupper(a)
+
+#define Y_INLINE __inline__
+
+#define YAFFS_LOSTNFOUND_NAME		"lost+found"
+#define YAFFS_LOSTNFOUND_PREFIX		"obj"
+
+/* #define YPRINTF(x) printk x */
+#define YMALLOC(x) kmalloc(x, GFP_NOFS)
+#define YFREE(x)   kfree(x)
+#define YMALLOC_ALT(x) vmalloc(x)
+#define YFREE_ALT(x)   vfree(x)
+#define YMALLOC_DMA(x) YMALLOC(x)
+
+#define YYIELD() schedule()
+#define Y_DUMP_STACK() dump_stack()
+
+#define YAFFS_ROOT_MODE			0755
+#define YAFFS_LOSTNFOUND_MODE		0700
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+#define Y_CURRENT_TIME CURRENT_TIME.tv_sec
+#define Y_TIME_CONVERT(x) (x).tv_sec
+#else
+#define Y_CURRENT_TIME CURRENT_TIME
+#define Y_TIME_CONVERT(x) (x)
+#endif
+
+#define yaffs_sum_cmp(x, y) ((x) == (y))
+#define yaffs_strcmp(a, b) strcmp(a, b)
+
+#define TENDSTR "\n"
+#define TSTR(x) KERN_DEBUG x
+#define TCONT(x) x
+#define TOUT(p) printk p
+
+#define compile_time_assertion(assertion) \
+	({ int x = __builtin_choose_expr(assertion, 0, (void)0); (void) x; })
+
+#elif defined CONFIG_YAFFS_DIRECT
+
+#define MTD_VERSION_CODE MTD_VERSION(2, 6, 22)
+
+/* Direct interface */
+#include "ydirectenv.h"
+
+#elif defined CONFIG_YAFFS_UTIL
+
+/* Stuff for YAFFS utilities */
+
+#include "stdlib.h"
+#include "stdio.h"
+#include "string.h"
+
+
+#define YMALLOC(x) malloc(x)
+#define YFREE(x)   free(x)
+#define YMALLOC_ALT(x) malloc(x)
+#define YFREE_ALT(x) free(x)
+
+#define YCHAR char
+#define YUCHAR unsigned char
+#define _Y(x)     x
+#define yaffs_strcat(a, b)     strcat(a, b)
+#define yaffs_strcpy(a, b)     strcpy(a, b)
+#define yaffs_strncpy(a, b, c) strncpy(a, b, c)
+#define yaffs_strnlen(s,m)	       strnlen(s,m)
+#define yaffs_sprintf	       sprintf
+#define yaffs_toupper(a)       toupper(a)
+
+#define Y_INLINE inline
+
+/* #define YINFO(s) YPRINTF(( __FILE__ " %d %s\n",__LINE__,s)) */
+/* #define YALERT(s) YINFO(s) */
+
+#define TENDSTR "\n"
+#define TSTR(x) x
+#define TOUT(p) printf p
+
+#define YAFFS_LOSTNFOUND_NAME		"lost+found"
+#define YAFFS_LOSTNFOUND_PREFIX		"obj"
+/* #define YPRINTF(x) printf x */
+
+#define YAFFS_ROOT_MODE			0755
+#define YAFFS_LOSTNFOUND_MODE		0700
+
+#define yaffs_sum_cmp(x, y) ((x) == (y))
+#define yaffs_strcmp(a, b) strcmp(a, b)
+
+#else
+/* Should have specified a configuration type */
+#error Unknown configuration
+
+#endif
+
+#if defined(CONFIG_YAFFS_DIRECT) || defined(CONFIG_YAFFS_WINCE)
+
+#ifdef CONFIG_YAFFSFS_PROVIDE_VALUES
+
+#ifndef O_RDONLY
+#define O_RDONLY        00
+#endif
+
+#ifndef O_WRONLY
+#define O_WRONLY	01
+#endif
+
+#ifndef O_RDWR
+#define O_RDWR		02
+#endif
+
+#ifndef O_CREAT		
+#define O_CREAT 	0100
+#endif
+
+#ifndef O_EXCL
+#define O_EXCL		0200
+#endif
+
+#ifndef O_TRUNC
+#define O_TRUNC		01000
+#endif
+
+#ifndef O_APPEND
+#define O_APPEND	02000
+#endif
+
+#ifndef SEEK_SET
+#define SEEK_SET	0
+#endif
+
+#ifndef SEEK_CUR
+#define SEEK_CUR	1
+#endif
+
+#ifndef SEEK_END
+#define SEEK_END	2
+#endif
+
+#ifndef EBUSY
+#define EBUSY	16
+#endif
+
+#ifndef ENODEV
+#define ENODEV	19
+#endif
+
+#ifndef EINVAL
+#define EINVAL	22
+#endif
+
+#ifndef EBADF
+#define EBADF	9
+#endif
+
+#ifndef EACCES
+#define EACCES	13
+#endif
+
+#ifndef EXDEV	
+#define EXDEV	18
+#endif
+
+#ifndef ENOENT
+#define ENOENT	2
+#endif
+
+#ifndef ENOSPC
+#define ENOSPC	28
+#endif
+
+#ifndef ERANGE
+#define ERANGE 34
+#endif
+
+#ifndef ENODATA
+#define ENODATA 61
+#endif
+
+#ifndef ENOTEMPTY
+#define ENOTEMPTY 39
+#endif
+
+#ifndef ENAMETOOLONG
+#define ENAMETOOLONG 36
+#endif
+
+#ifndef ENOMEM
+#define ENOMEM 12
+#endif
+
+#ifndef EEXIST
+#define EEXIST 17
+#endif
+
+#ifndef ENOTDIR
+#define ENOTDIR 20
+#endif
+
+#ifndef EISDIR
+#define EISDIR 21
+#endif
+
+
+// Mode flags
+
+#ifndef S_IFMT
+#define S_IFMT		0170000
+#endif
+
+#ifndef S_IFLNK
+#define S_IFLNK		0120000
+#endif
+
+#ifndef S_IFDIR
+#define S_IFDIR		0040000
+#endif
+
+#ifndef S_IFREG
+#define S_IFREG		0100000
+#endif
+
+#ifndef S_IREAD 
+#define S_IREAD		0000400
+#endif
+
+#ifndef S_IWRITE
+#define	S_IWRITE	0000200
+#endif
+
+#ifndef S_IEXEC
+#define	S_IEXEC	0000100
+#endif
+
+#ifndef XATTR_CREATE
+#define XATTR_CREATE 1
+#endif
+
+#ifndef XATTR_REPLACE
+#define XATTR_REPLACE 2
+#endif
+
+#ifndef R_OK
+#define R_OK	4
+#define W_OK	2
+#define X_OK	1
+#define F_OK	0
+#endif
+
+#else
+#include <errno.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#endif
+
+#endif
+
+#ifndef Y_DUMP_STACK
+#define Y_DUMP_STACK() do { } while (0)
+#endif
+
+#ifndef YBUG
+#define YBUG() do {\
+	T(YAFFS_TRACE_BUG,\
+		(TSTR("==>> yaffs bug: " __FILE__ " %d" TENDSTR),\
+		__LINE__));\
+	Y_DUMP_STACK();\
+} while (0)
+#endif
+
+
+#endif
-- 
1.7.3.2.146.gca209

Re: [PATCH 28/29] Staging: yaffs2: yportenv.h: Add file

[Pekka Enberg]

On Mon, Nov 1, 2010 at 8:41 PM, Tracey Dent <tdent48227@gmail.com> wrote:
> Adding files to yaffs2 directory.
>
> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> ---
>  drivers/staging/yaffs2/yportenv.h |  333 +++++++++++++++++++++++++++++++++++++
>  1 files changed, 333 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/yaffs2/yportenv.h
>
> diff --git a/drivers/staging/yaffs2/yportenv.h b/drivers/staging/yaffs2/yportenv.h
> new file mode 100644
> index 0000000..2f9063b
> --- /dev/null
> +++ b/drivers/staging/yaffs2/yportenv.h
> +#define YCHAR char
> +#define YUCHAR unsigned char
> +#define _Y(x)     x
> +#define yaffs_strcat(a, b)     strcat(a, b)
> +#define yaffs_strcpy(a, b)     strcpy(a, b)
> +#define yaffs_strncpy(a, b, c) strncpy(a, b, c)
> +#define yaffs_strncmp(a, b, c) strncmp(a, b, c)
> +#define yaffs_strnlen(s,m)     strnlen(s,m)
> +#define yaffs_sprintf         sprintf
> +#define yaffs_toupper(a)       toupper(a)
> +
> +#define Y_INLINE __inline__
> +
> +#define YAFFS_LOSTNFOUND_NAME          "lost+found"
> +#define YAFFS_LOSTNFOUND_PREFIX                "obj"
> +
> +/* #define YPRINTF(x) printk x */
> +#define YMALLOC(x) kmalloc(x, GFP_NOFS)
> +#define YFREE(x)   kfree(x)
> +#define YMALLOC_ALT(x) vmalloc(x)
> +#define YFREE_ALT(x)   vfree(x)
> +#define YMALLOC_DMA(x) YMALLOC(x)
> +
> +#define YYIELD() schedule()
> +#define Y_DUMP_STACK() dump_stack()

[snip]

Pretty much all wrappers in this header file want to be killed.
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[PATCH 29/29] Staging: yaffs2: TODO: Add TODO file

[Tracey Dent]

Inital TODO file.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/TODO |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/TODO

diff --git a/drivers/staging/yaffs2/TODO b/drivers/staging/yaffs2/TODO
new file mode 100644
index 0000000..be6a836
--- /dev/null
+++ b/drivers/staging/yaffs2/TODO
@@ -0,0 +1,6 @@
+TODO :
+
+	* checkpatch.pl fixes
+	* sparse fixes
+
+Plase send patches to Greg Kroah-Hartman <greg@kroah.com>
-- 
1.7.3.2.146.gca209

Re: [PATCH 29/29] Staging: yaffs2: TODO: Add TODO file

[Pekka Enberg]

On Mon, Nov 1, 2010 at 8:41 PM, Tracey Dent <tdent48227@gmail.com> wrote:
> Inital TODO file.
>
> Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> ---
>  drivers/staging/yaffs2/TODO |    6 ++++++
>  1 files changed, 6 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/yaffs2/TODO
>
> diff --git a/drivers/staging/yaffs2/TODO b/drivers/staging/yaffs2/TODO
> new file mode 100644
> index 0000000..be6a836
> --- /dev/null
> +++ b/drivers/staging/yaffs2/TODO
> @@ -0,0 +1,6 @@
> +TODO :
> +
> +       * checkpatch.pl fixes
> +       * sparse fixes

 * drop typedefs
 * drop Linux kernel version compatibility macros
 * drop other strange compatibility macros
 * fix formatting with Lindent
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Re: [PATCH 29/29] Staging: yaffs2: TODO: Add TODO file

[Charles Manning]

On Tuesday 02 November 2010 08:20:27 Pekka Enberg wrote:
> On Mon, Nov 1, 2010 at 8:41 PM, Tracey Dent <tdent48227@gmail.com> wrote:
> > Inital TODO file.
> >
> > Signed-off-by: Tracey Dent <tdent48227@gmail.com>
> > ---
> >  drivers/staging/yaffs2/TODO |    6 ++++++
> >  1 files changed, 6 insertions(+), 0 deletions(-)
> >  create mode 100644 drivers/staging/yaffs2/TODO
> >
> > diff --git a/drivers/staging/yaffs2/TODO b/drivers/staging/yaffs2/TODO
> > new file mode 100644
> > index 0000000..be6a836
> > --- /dev/null
> > +++ b/drivers/staging/yaffs2/TODO
> > @@ -0,0 +1,6 @@
> > +TODO :
> > +
> > +       * checkpatch.pl fixes
> > +       * sparse fixes
>
>  * drop typedefs
>  * drop Linux kernel version compatibility macros
>  * drop other strange compatibility macros
>  * fix formatting with Lindent

I am in the process of making up a new patch set for release within 24 hours 
that does the following:

* drops typedefs
* drops the last few camel case names
* replaces __u32 with u32 etc
* drops few remaining kernel version compatibility macros.
* cleans up #if 0 code
* clean up some of the headers etc reported today.

It is my goal to keep the code portable which is going to be a bit of a 
challenge, but I want to at least make an effort to do this.

Thanks to all for their comments etc. I appreciate the effort.

I shall be pushing this to git as well as sending out patches.


-- CHarles





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Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[David Daney]

On 11/01/2010 11:40 AM, Tracey Dent wrote:
> The patch sets puts the yaffs2 filesystem in the staging directory.
> It is all based on Charles git tree(http://github.com/cdhmanning/linux-yaffs-integration/).
> Everything is compile tested and it builds.
>
> This only the inital support and I will be sending more cleanup patches.
>
> Greg can you add the patch set into your staging-next tree.
> Also, It doesn't affect anything other than itself.
>
> Thanks,
>
> Tracey Dent

I am confused.

Are you and Charles Manning working together on this?

Did you write all this code or did Charles?  If it was Charles, why are 
there no From: and Signed-off-by headers for him?

Thanks in advance for enlightening us as to what is going on here,
David Daney

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[Greg KH]

On Mon, Nov 01, 2010 at 11:55:39AM -0700, David Daney wrote:
> On 11/01/2010 11:40 AM, Tracey Dent wrote:
>> The patch sets puts the yaffs2 filesystem in the staging directory.
>> It is all based on Charles git tree(http://github.com/cdhmanning/linux-yaffs-integration/).
>> Everything is compile tested and it builds.
>>
>> This only the inital support and I will be sending more cleanup patches.
>>
>> Greg can you add the patch set into your staging-next tree.
>> Also, It doesn't affect anything other than itself.
>>
>> Thanks,
>>
>> Tracey Dent
>
> I am confused.
>
> Are you and Charles Manning working together on this?
>
> Did you write all this code or did Charles?  If it was Charles, why are 
> there no From: and Signed-off-by headers for him?

Yeah, we need to get the authorship correct here.  Charles, do you ack
these patches?

thanks,

greg k-h

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[Charles Manning]

On Tuesday 02 November 2010 07:55:39 David Daney wrote:
> On 11/01/2010 11:40 AM, Tracey Dent wrote:
> > The patch sets puts the yaffs2 filesystem in the staging directory.
> > It is all based on Charles git
> > tree(http://github.com/cdhmanning/linux-yaffs-integration/). Everything
> > is compile tested and it builds.
> >
> > This only the inital support and I will be sending more cleanup patches.
> >
> > Greg can you add the patch set into your staging-next tree.
> > Also, It doesn't affect anything other than itself.
> >
> > Thanks,
> >
> > Tracey Dent
>
> I am confused.
>
> Are you and Charles Manning working together on this?
>
> Did you write all this code or did Charles?  If it was Charles, why are
> there no From: and Signed-off-by headers for him?
>
> Thanks in advance for enlightening us as to what is going on here,
> David Daney

We are not working together on this, but I do appreciate the effort in helping 
bring to a head what people like/dislike.

I am trying to keep the kernel yaffs consistent with the yaffs.net yaffs so 
that it is easier to add changes from yaffs.net.

-- Charles

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[Tracey Dent]

On 11/1/10, Charles Manning <manningc2@actrix.gen.nz> wrote:
> On Tuesday 02 November 2010 07:55:39 David Daney wrote:
>> On 11/01/2010 11:40 AM, Tracey Dent wrote:
>> > The patch sets puts the yaffs2 filesystem in the staging directory.
>> > It is all based on Charles git
>> > tree(http://github.com/cdhmanning/linux-yaffs-integration/). Everything
>> > is compile tested and it builds.
>> >
>> > This only the inital support and I will be sending more cleanup patches.
>> >
>> > Greg can you add the patch set into your staging-next tree.
>> > Also, It doesn't affect anything other than itself.
>> >
>> > Thanks,
>> >
>> > Tracey Dent
>>
>> I am confused.
>>
>> Are you and Charles Manning working together on this?
>>
>> Did you write all this code or did Charles?  If it was Charles, why are
>> there no From: and Signed-off-by headers for him?

Yeah I forgot to change that. By adding a signed off line by him.

>>
>> Thanks in advance for enlightening us as to what is going on here,
>> David Daney
>
> We are not working together on this, but I do appreciate the effort in
> helping
> bring to a head what people like/dislike.
>
> I am trying to keep the kernel yaffs consistent with the yaffs.net yaffs so
> that it is easier to add changes from yaffs.net.

All I did was take your tree and put it in patch form. So nothing
should change, except I added a general *TODO file.

So you can ack this and get it in Greg'ss Staging-next tree, if you want?
>
> -- Charles
>
>

Regards,

Tracey Dent

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[David Daney]

On 11/01/2010 12:14 PM, Charles Manning wrote:
> On Tuesday 02 November 2010 07:55:39 David Daney wrote:
>> On 11/01/2010 11:40 AM, Tracey Dent wrote:
>>> The patch sets puts the yaffs2 filesystem in the staging directory.
>>> It is all based on Charles git
>>> tree(http://github.com/cdhmanning/linux-yaffs-integration/). Everything
>>> is compile tested and it builds.
>>>
>>> This only the inital support and I will be sending more cleanup patches.
>>>
>>> Greg can you add the patch set into your staging-next tree.
>>> Also, It doesn't affect anything other than itself.
>>>
>>> Thanks,
>>>
>>> Tracey Dent
>>
>> I am confused.
>>
>> Are you and Charles Manning working together on this?
>>
>> Did you write all this code or did Charles?  If it was Charles, why are
>> there no From: and Signed-off-by headers for him?
>>
>> Thanks in advance for enlightening us as to what is going on here,
>> David Daney
>
> We are not working together on this, but I do appreciate the effort in helping
> bring to a head what people like/dislike.
>
> I am trying to keep the kernel yaffs consistent with the yaffs.net yaffs so
> that it is easier to add changes from yaffs.net.
>

Great.  Thanks for clearing things up.

I will offer my unsolicited opinion:

Charles has obviously expended great effort on yaffs2.  He has a git 
repository hosting the code, and has expressed a desire to get the code 
fit for merging.  For Tracey Dent to come along and hijack the entire 
effort, would anger me if I were in Charles' place.

Having used yaffs2 in the past, I would like to see the code in the 
kernel.  Having it come via Charles would seem to make sense.

David Daney

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[Charles Manning]

On Tuesday 02 November 2010 08:24:42 David Daney wrote:
> On 11/01/2010 12:14 PM, Charles Manning wrote:
> > On Tuesday 02 November 2010 07:55:39 David Daney wrote:
> >> On 11/01/2010 11:40 AM, Tracey Dent wrote:
> >>> The patch sets puts the yaffs2 filesystem in the staging directory.
> >>> It is all based on Charles git
> >>> tree(http://github.com/cdhmanning/linux-yaffs-integration/). Everything
> >>> is compile tested and it builds.
> >>>
> >>> This only the inital support and I will be sending more cleanup
> >>> patches.
> >>>
> >>> Greg can you add the patch set into your staging-next tree.
> >>> Also, It doesn't affect anything other than itself.
> >>>
> >>> Thanks,
> >>>
> >>> Tracey Dent
> >>
> >> I am confused.
> >>
> >> Are you and Charles Manning working together on this?
> >>
> >> Did you write all this code or did Charles?  If it was Charles, why are
> >> there no From: and Signed-off-by headers for him?
> >>
> >> Thanks in advance for enlightening us as to what is going on here,
> >> David Daney
> >
> > We are not working together on this, but I do appreciate the effort in
> > helping bring to a head what people like/dislike.
> >
> > I am trying to keep the kernel yaffs consistent with the yaffs.net yaffs
> > so that it is easier to add changes from yaffs.net.
>
> Great.  Thanks for clearing things up.
>
> I will offer my unsolicited opinion:
>
> Charles has obviously expended great effort on yaffs2.  He has a git
> repository hosting the code, and has expressed a desire to get the code
> fit for merging.  For Tracey Dent to come along and hijack the entire
> effort, would anger me if I were in Charles' place.

I don't see any malicious intent from Tracey, but I do wish to see some 
recognition for 8+ years of effort :-).

> Having used yaffs2 in the past, I would like to see the code in the
> kernel.  Having it come via Charles would seem to make sense.
>

A prime consideration from me is to try keep the kernel and yaffs.net versions 
of yaffs very close to consistent. That will allow me to continue to use my 
existing out-of-kernel dev tools and have other benefits.


-- CHarles

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[Tracey Dent]

On 11/1/10, Charles Manning <manningc2@actrix.gen.nz> wrote:
> On Tuesday 02 November 2010 08:24:42 David Daney wrote:
>> On 11/01/2010 12:14 PM, Charles Manning wrote:
>> > On Tuesday 02 November 2010 07:55:39 David Daney wrote:
>> >> On 11/01/2010 11:40 AM, Tracey Dent wrote:
>> >>> The patch sets puts the yaffs2 filesystem in the staging directory.
>> >>> It is all based on Charles git
>> >>> tree(http://github.com/cdhmanning/linux-yaffs-integration/).
>> >>> Everything
>> >>> is compile tested and it builds.
>> >>>
>> >>> This only the inital support and I will be sending more cleanup
>> >>> patches.
>> >>>
>> >>> Greg can you add the patch set into your staging-next tree.
>> >>> Also, It doesn't affect anything other than itself.
>> >>>
>> >>> Thanks,
>> >>>
>> >>> Tracey Dent
>> >>
>> >> I am confused.
>> >>
>> >> Are you and Charles Manning working together on this?
>> >>
>> >> Did you write all this code or did Charles?  If it was Charles, why are
>> >> there no From: and Signed-off-by headers for him?
>> >>
>> >> Thanks in advance for enlightening us as to what is going on here,
>> >> David Daney
>> >
>> > We are not working together on this, but I do appreciate the effort in
>> > helping bring to a head what people like/dislike.
>> >
>> > I am trying to keep the kernel yaffs consistent with the yaffs.net yaffs
>> > so that it is easier to add changes from yaffs.net.
>>
>> Great.  Thanks for clearing things up.
>>
>> I will offer my unsolicited opinion:
>>
>> Charles has obviously expended great effort on yaffs2.  He has a git
>> repository hosting the code, and has expressed a desire to get the code
>> fit for merging.  For Tracey Dent to come along and hijack the entire
>> effort, would anger me if I were in Charles' place.
>
> I don't see any malicious intent from Tracey, but I do wish to see some
> recognition for 8+ years of effort :-).
>

I can resend it with your signed-off-by line instead of mine.

>> Having used yaffs2 in the past, I would like to see the code in the
>> kernel.  Having it come via Charles would seem to make sense.
>>
>
> A prime consideration from me is to try keep the kernel and yaffs.net
> versions
> of yaffs very close to consistent. That will allow me to continue to use my
> existing out-of-kernel dev tools and have other benefits.
>
Like I said its exactly from the git
tree(http://github.com/cdhmanning/linux-yaffs-integration/). It should
still be compatible with all the existing tools.

>
> -- CHarles
>
>


Tracey Dent

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[Greg KH]

On Mon, Nov 01, 2010 at 03:36:13PM -0400, Tracey Dent wrote:
> On 11/1/10, Charles Manning <manningc2@actrix.gen.nz> wrote:
> > On Tuesday 02 November 2010 08:24:42 David Daney wrote:
> >> On 11/01/2010 12:14 PM, Charles Manning wrote:
> >> > On Tuesday 02 November 2010 07:55:39 David Daney wrote:
> >> >> On 11/01/2010 11:40 AM, Tracey Dent wrote:
> >> >>> The patch sets puts the yaffs2 filesystem in the staging directory.
> >> >>> It is all based on Charles git
> >> >>> tree(http://github.com/cdhmanning/linux-yaffs-integration/).
> >> >>> Everything
> >> >>> is compile tested and it builds.
> >> >>>
> >> >>> This only the inital support and I will be sending more cleanup
> >> >>> patches.
> >> >>>
> >> >>> Greg can you add the patch set into your staging-next tree.
> >> >>> Also, It doesn't affect anything other than itself.
> >> >>>
> >> >>> Thanks,
> >> >>>
> >> >>> Tracey Dent
> >> >>
> >> >> I am confused.
> >> >>
> >> >> Are you and Charles Manning working together on this?
> >> >>
> >> >> Did you write all this code or did Charles?  If it was Charles, why are
> >> >> there no From: and Signed-off-by headers for him?
> >> >>
> >> >> Thanks in advance for enlightening us as to what is going on here,
> >> >> David Daney
> >> >
> >> > We are not working together on this, but I do appreciate the effort in
> >> > helping bring to a head what people like/dislike.
> >> >
> >> > I am trying to keep the kernel yaffs consistent with the yaffs.net yaffs
> >> > so that it is easier to add changes from yaffs.net.
> >>
> >> Great.  Thanks for clearing things up.
> >>
> >> I will offer my unsolicited opinion:
> >>
> >> Charles has obviously expended great effort on yaffs2.  He has a git
> >> repository hosting the code, and has expressed a desire to get the code
> >> fit for merging.  For Tracey Dent to come along and hijack the entire
> >> effort, would anger me if I were in Charles' place.
> >
> > I don't see any malicious intent from Tracey, but I do wish to see some
> > recognition for 8+ years of effort :-).
> >
> 
> I can resend it with your signed-off-by line instead of mine.

You need to properly credit _who_ did the code in the first place.  And
your patches did not do that at all, which is very bad, and rude, and
something that we care deeply about.

Please read the file, Documentation/SubmittingPatches for how to
properly attribute the author of the patch when you send it out.

I'm not going to take this as-is because of this problem, and neither
will any other maintainer.  Someone can resend it with the proper author
and signed-off-by stuff and I'll be glad to look at it again then.

thanks,

greg k-h

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[Tracey Dent]

On 11/1/10, Greg KH <greg@kroah.com> wrote:
> On Mon, Nov 01, 2010 at 03:36:13PM -0400, Tracey Dent wrote:
>> On 11/1/10, Charles Manning <manningc2@actrix.gen.nz> wrote:
>> > On Tuesday 02 November 2010 08:24:42 David Daney wrote:
>> >> On 11/01/2010 12:14 PM, Charles Manning wrote:
>> >> > On Tuesday 02 November 2010 07:55:39 David Daney wrote:
>> >> >> On 11/01/2010 11:40 AM, Tracey Dent wrote:
>> >> >>> The patch sets puts the yaffs2 filesystem in the staging directory.
>> >> >>> It is all based on Charles git
>> >> >>> tree(http://github.com/cdhmanning/linux-yaffs-integration/).
>> >> >>> Everything
>> >> >>> is compile tested and it builds.
>> >> >>>
>> >> >>> This only the inital support and I will be sending more cleanup
>> >> >>> patches.
>> >> >>>
>> >> >>> Greg can you add the patch set into your staging-next tree.
>> >> >>> Also, It doesn't affect anything other than itself.
>> >> >>>
>> >> >>> Thanks,
>> >> >>>
>> >> >>> Tracey Dent
>> >> >>
>> >> >> I am confused.
>> >> >>
>> >> >> Are you and Charles Manning working together on this?
>> >> >>
>> >> >> Did you write all this code or did Charles?  If it was Charles, why
>> >> >> are
>> >> >> there no From: and Signed-off-by headers for him?
>> >> >>
>> >> >> Thanks in advance for enlightening us as to what is going on here,
>> >> >> David Daney
>> >> >
>> >> > We are not working together on this, but I do appreciate the effort
>> >> > in
>> >> > helping bring to a head what people like/dislike.
>> >> >
>> >> > I am trying to keep the kernel yaffs consistent with the yaffs.net
>> >> > yaffs
>> >> > so that it is easier to add changes from yaffs.net.
>> >>
>> >> Great.  Thanks for clearing things up.
>> >>
>> >> I will offer my unsolicited opinion:
>> >>
>> >> Charles has obviously expended great effort on yaffs2.  He has a git
>> >> repository hosting the code, and has expressed a desire to get the code
>> >> fit for merging.  For Tracey Dent to come along and hijack the entire
>> >> effort, would anger me if I were in Charles' place.
>> >
>> > I don't see any malicious intent from Tracey, but I do wish to see some
>> > recognition for 8+ years of effort :-).
>> >
>>
>> I can resend it with your signed-off-by line instead of mine.
>
> You need to properly credit _who_ did the code in the first place.  And
> your patches did not do that at all, which is very bad, and rude, and
> something that we care deeply about.
>
> Please read the file, Documentation/SubmittingPatches for how to
> properly attribute the author of the patch when you send it out.
>
> I'm not going to take this as-is because of this problem, and neither
> will any other maintainer.  Someone can resend it with the proper author
> and signed-off-by stuff and I'll be glad to look at it again then.
>

Sorry for not giving credit. I will resend following patch set with
proper credits.

> thanks,
>
> greg k-h

Sorry,

Tracey Dent

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[David Daney]

On 11/01/2010 01:46 PM, Tracey Dent wrote:
> On 11/1/10, Greg KH<greg@kroah.com>  wrote:
[...]
>>
>> You need to properly credit _who_ did the code in the first place.  And
>> your patches did not do that at all, which is very bad, and rude, and
>> something that we care deeply about.
>>
>> Please read the file, Documentation/SubmittingPatches for how to
>> properly attribute the author of the patch when you send it out.
>>
>> I'm not going to take this as-is because of this problem, and neither
>> will any other maintainer.  Someone can resend it with the proper author
>> and signed-off-by stuff and I'll be glad to look at it again then.
>>
>
> Sorry for not giving credit. I will resend following patch set with
> proper credits.
>

It is not a race to see who can spam lkml first.  Please consider 
coordinating with Charles, and perhaps even defer to him if he wishes to 
send the patches (or even have them pulled from his git repository).

David Daney.

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[Tracey Dent]

Sorry for all the noise. It wont happen again. I just did something
without thinking.

regards

Tracey

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[Greg KH]

On Mon, Nov 01, 2010 at 09:37:33PM -0400, Tracey Dent wrote:
> Sorry for all the noise. It wont happen again. I just did something
> without thinking.

There's nothing wrong with that, just get the patches correct next time
and all will be fine :)

thanks,

greg k-h

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[Tracey Dent]

On 11/1/10, Greg KH <greg@kroah.com> wrote:
> On Mon, Nov 01, 2010 at 09:37:33PM -0400, Tracey Dent wrote:
>> Sorry for all the noise. It wont happen again. I just did something
>> without thinking.
>
> There's nothing wrong with that, just get the patches correct next time
> and all will be fine :)

But what about what David had said, that I never even
coordinated with Charles to see if he even wanted me to do
this patch set.

>
> thanks,
>
> greg k-h
>

regard

tracey d

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[Tracey Dent]

On 11/1/10, David Daney <ddaney@caviumnetworks.com> wrote:
> On 11/01/2010 12:14 PM, Charles Manning wrote:
>> On Tuesday 02 November 2010 07:55:39 David Daney wrote:
>>> On 11/01/2010 11:40 AM, Tracey Dent wrote:
>>>> The patch sets puts the yaffs2 filesystem in the staging directory.
>>>> It is all based on Charles git
>>>> tree(http://github.com/cdhmanning/linux-yaffs-integration/). Everything
>>>> is compile tested and it builds.
>>>>
>>>> This only the inital support and I will be sending more cleanup patches.
>>>>
>>>> Greg can you add the patch set into your staging-next tree.
>>>> Also, It doesn't affect anything other than itself.
>>>>
>>>> Thanks,
>>>>
>>>> Tracey Dent
>>>
>>> I am confused.
>>>
>>> Are you and Charles Manning working together on this?
>>>
>>> Did you write all this code or did Charles?  If it was Charles, why are
>>> there no From: and Signed-off-by headers for him?
>>>
>>> Thanks in advance for enlightening us as to what is going on here,
>>> David Daney
>>
>> We are not working together on this, but I do appreciate the effort in
>> helping
>> bring to a head what people like/dislike.
>>
>> I am trying to keep the kernel yaffs consistent with the yaffs.net yaffs
>> so
>> that it is easier to add changes from yaffs.net.
>>
>
> Great.  Thanks for clearing things up.
>
> I will offer my unsolicited opinion:
>
> Charles has obviously expended great effort on yaffs2.  He has a git
> repository hosting the code, and has expressed a desire to get the code
> fit for merging.  For Tracey Dent to come along and hijack the entire
> effort, would anger me if I were in Charles' place.

I didn't mean to hijack, I was just trying to help. :(

>
> Having used yaffs2 in the past, I would like to see the code in the
> kernel.  Having it come via Charles would seem to make sense.
>

But regardless it shouldn't matter who submitted the patches, as long
as we can get it into mainline.
> David Daney
>

Tracey Dent

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[David Daney]

On 11/01/2010 12:34 PM, Tracey Dent wrote:
> On 11/1/10, David Daney<ddaney@caviumnetworks.com>  wrote:
>> On 11/01/2010 12:14 PM, Charles Manning wrote:
>>> On Tuesday 02 November 2010 07:55:39 David Daney wrote:
>>>> On 11/01/2010 11:40 AM, Tracey Dent wrote:
>>>>> The patch sets puts the yaffs2 filesystem in the staging directory.
>>>>> It is all based on Charles git
>>>>> tree(http://github.com/cdhmanning/linux-yaffs-integration/). Everything
>>>>> is compile tested and it builds.
>>>>>
>>>>> This only the inital support and I will be sending more cleanup patches.
>>>>>
>>>>> Greg can you add the patch set into your staging-next tree.
>>>>> Also, It doesn't affect anything other than itself.
>>>>>
>>>>> Thanks,
>>>>>
>>>>> Tracey Dent
>>>>
>>>> I am confused.
>>>>
>>>> Are you and Charles Manning working together on this?
>>>>
>>>> Did you write all this code or did Charles?  If it was Charles, why are
>>>> there no From: and Signed-off-by headers for him?
>>>>
>>>> Thanks in advance for enlightening us as to what is going on here,
>>>> David Daney
>>>
>>> We are not working together on this, but I do appreciate the effort in
>>> helping
>>> bring to a head what people like/dislike.
>>>
>>> I am trying to keep the kernel yaffs consistent with the yaffs.net yaffs
>>> so
>>> that it is easier to add changes from yaffs.net.
>>>
>>
>> Great.  Thanks for clearing things up.
>>
>> I will offer my unsolicited opinion:
>>
>> Charles has obviously expended great effort on yaffs2.  He has a git
>> repository hosting the code, and has expressed a desire to get the code
>> fit for merging.  For Tracey Dent to come along and hijack the entire
>> effort, would anger me if I were in Charles' place.
>
> I didn't mean to hijack, I was just trying to help. :(
>
>>
>> Having used yaffs2 in the past, I would like to see the code in the
>> kernel.  Having it come via Charles would seem to make sense.
>>
>
> But regardless it shouldn't matter who submitted the patches, as long
> as we can get it into mainline.

In the very real world we live in, proper attribution of kernel patch 
authorship can make a concrete difference in employment decisions.  And 
even without the monetary considerations, the health of the 'ecosystem' 
in which we operate is damaged if credit is not granted where due.

David Daney

Re: [PATCH 0/29] Staging: Add yaffs2 filesystem

[Pekka Enberg]

On Mon, Nov 1, 2010 at 8:40 PM, Tracey Dent <tdent48227@gmail.com> wrote:
> The patch sets puts the yaffs2 filesystem in the staging directory.
> It is all based on Charles git tree(http://github.com/cdhmanning/linux-yaffs-integration/).
> Everything is compile tested and it builds.
>
> This only the inital support and I will be sending more cleanup patches.
>
> Greg can you add the patch set into your staging-next tree.
> Also, It doesn't affect anything other than itself.

I know Greg is happy to take this in but it would also be interesting
to know what's the benefit of YAFFS2 over existing filesystems.