* [PATCH 01/20 take 4] UBI: on-flash data structures header
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
@ 2007-03-23 16:43 ` Artem Bityutskiy
2007-03-23 16:43 ` [PATCH 02/20 take 4] UBI: user-space API header Artem Bityutskiy
` (18 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:43 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 15817 bytes --]
diff -auNrp tmp-from/include/mtd/ubi-header.h tmp-to/include/mtd/ubi-header.h
--- tmp-from/include/mtd/ubi-header.h 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/include/mtd/ubi-header.h 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,360 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Thomas Gleixner
+ * Frank Haverkamp
+ * Oliver Lohmann
+ * Andreas Arnez
+ */
+
+/*
+ * This file defines the layout of UBI headers and all the other UBI on-flash
+ * data structures. May be included by user-space.
+ */
+
+#ifndef __UBI_HEADER_H__
+#define __UBI_HEADER_H__
+
+#include <asm/byteorder.h>
+
+/* The version of UBI images supported by this implementation */
+#define UBI_VERSION 1
+
+/* The highest erase counter value supported by this implementation */
+#define UBI_MAX_ERASECOUNTER 0x7FFFFFFF
+
+/* The initial CRC32 value used when calculating CRC checksums */
+#define UBI_CRC32_INIT 0xFFFFFFFFU
+
+/* Erase counter header magic number (ASCII "UBI#") */
+#define UBI_EC_HDR_MAGIC 0x55424923
+/* Volume identifier header magic number (ASCII "UBI!") */
+#define UBI_VID_HDR_MAGIC 0x55424921
+
+/*
+ * Volume type constants used in the volume identifier header.
+ *
+ * @UBI_VID_DYNAMIC: dynamic volume
+ * @UBI_VID_STATIC: static volume
+ */
+enum {
+ UBI_VID_DYNAMIC = 1,
+ UBI_VID_STATIC = 2
+};
+
+/*
+ * Compatibility constants used by internal volumes.
+ *
+ * @UBI_COMPAT_DELETE: delete this internal volume before anything is written
+ * to the flash
+ * @UBI_COMPAT_RO: attach this device in read-only mode
+ * @UBI_COMPAT_PRESERVE: preserve this internal volume - do not touch its
+ * physical eraseblocks, don't allow the wear-leveling unit to move them
+ * @UBI_COMPAT_REJECT: reject this UBI image
+ */
+enum {
+ UBI_COMPAT_DELETE = 1,
+ UBI_COMPAT_RO = 2,
+ UBI_COMPAT_PRESERVE = 4,
+ UBI_COMPAT_REJECT = 5
+};
+
+/*
+ * ubi16_t/ubi32_t/ubi64_t - 16, 32, and 64-bit integers used in UBI on-flash
+ * data structures.
+ */
+typedef struct {
+ uint16_t int16;
+} __attribute__ ((packed)) ubi16_t;
+
+typedef struct {
+ uint32_t int32;
+} __attribute__ ((packed)) ubi32_t;
+
+typedef struct {
+ uint64_t int64;
+} __attribute__ ((packed)) ubi64_t;
+
+/*
+ * In this implementation of UBI uses the big-endian format for on-flash
+ * integers. The below are the corresponding conversion macros.
+ */
+#define cpu_to_ubi16(x) ((ubi16_t){__cpu_to_be16(x)})
+#define ubi16_to_cpu(x) ((uint16_t)__be16_to_cpu((x).int16))
+
+#define cpu_to_ubi32(x) ((ubi32_t){__cpu_to_be32(x)})
+#define ubi32_to_cpu(x) ((uint32_t)__be32_to_cpu((x).int32))
+
+#define cpu_to_ubi64(x) ((ubi64_t){__cpu_to_be64(x)})
+#define ubi64_to_cpu(x) ((uint64_t)__be64_to_cpu((x).int64))
+
+/* Sizes of UBI headers */
+#define UBI_EC_HDR_SIZE sizeof(struct ubi_ec_hdr)
+#define UBI_VID_HDR_SIZE sizeof(struct ubi_vid_hdr)
+
+/* Sizes of UBI headers without the ending CRC */
+#define UBI_EC_HDR_SIZE_CRC (UBI_EC_HDR_SIZE - sizeof(ubi32_t))
+#define UBI_VID_HDR_SIZE_CRC (UBI_VID_HDR_SIZE - sizeof(ubi32_t))
+
+/**
+ * struct ubi_ec_hdr - UBI erase counter header.
+ * @magic: erase counter header magic number (%UBI_EC_HDR_MAGIC)
+ * @version: version of UBI implementation which is supposed to accept this
+ * UBI image
+ * @padding1: reserved for future, zeroes
+ * @ec: the erase counter
+ * @vid_hdr_offset: where the VID header starts
+ * @data_offset: where the user data start
+ * @padding2: reserved for future, zeroes
+ * @hdr_crc: erase counter header CRC checksum
+ *
+ * The erase counter header takes 64 bytes and has a plenty of unused space for
+ * future usage. The unused fields are zeroed. The @version field is used to
+ * indicate the version of UBI implementation which is supposed to be able to
+ * work with this UBI image. If @version is greater then the current UBI
+ * version, the image is rejected. This may be useful in future if something
+ * is changed radically. This field is duplicated in the volume identifier
+ * header.
+ *
+ * The @vid_hdr_offset and @data_offset fields contain the offset of the the
+ * volume identifier header and user data, relative to the beginning of the
+ * physical eraseblock. These values have to be the same for all physical
+ * eraseblocks.
+ */
+struct ubi_ec_hdr {
+ ubi32_t magic;
+ uint8_t version;
+ uint8_t padding1[3];
+ ubi64_t ec; /* Warning: the current limit is 31-bit anyway! */
+ ubi32_t vid_hdr_offset;
+ ubi32_t data_offset;
+ uint8_t padding2[36];
+ ubi32_t hdr_crc;
+} __attribute__ ((packed));
+
+/**
+ * struct ubi_vid_hdr - on-flash UBI volume identifier header.
+ * @magic: volume identifier header magic number (%UBI_VID_HDR_MAGIC)
+ * @version: UBI implementation version which is supposed to accept this UBI
+ * image (%UBI_VERSION)
+ * @vol_type: volume type (%UBI_VID_DYNAMIC or %UBI_VID_STATIC)
+ * @copy_flag: if this logical eraseblock was copied from another physical
+ * eraseblock (for wear-leveling reasons)
+ * @compat: compatibility of this volume (%0, %UBI_COMPAT_DELETE,
+ * %UBI_COMPAT_IGNORE, %UBI_COMPAT_PRESERVE, or %UBI_COMPAT_REJECT)
+ * @vol_id: ID of this volume
+ * @lnum: logical eraseblock number
+ * @leb_ver: version of this logical eraseblock (IMPORTANT: obsolete, to be
+ * removed, kept only for not breaking older UBI users)
+ * @data_size: how many bytes of data this logical eraseblock contains
+ * @used_ebs: total number of used logical eraseblocks in this volume
+ * @data_pad: how many bytes at the end of this physical eraseblock are not
+ * used
+ * @data_crc: CRC checksum of the data stored in this logical eraseblock
+ * @padding1: reserved for future, zeroes
+ * @sqnum: sequence number
+ * @padding2: reserved for future, zeroes
+ * @hdr_crc: volume identifier header CRC checksum
+ *
+ * The @sqnum is the value of the global sequence counter at the time when this
+ * VID header was created. The global sequence counter is incremented each time
+ * UBI writes a new VID header to the flash, i.e. when it maps a logical
+ * eraseblock to a new physical eraseblock. The global sequence counter is an
+ * unsigned 64-bit integer and we assume it never overflows. The @sqnum
+ * (sequence number) is used to distinguish between older and newer versions of
+ * logical eraseblocks.
+ *
+ * There are 2 situations when there may be more then one physical eraseblock
+ * corresponding to the same logical eraseblock, i.e., having the same @vol_id
+ * and @lnum values in the volume identifier header. Suppose we have a logical
+ * eraseblock L and it is mapped to the physical eraseblock P.
+ *
+ * 1. Because UBI may erase physical eraseblocks asynchronously, the following
+ * situation is possible: L is asynchronously erased, so P is scheduled for
+ * erasure, then L is written to,i.e. mapped to another physical eraseblock P1,
+ * so P1 is written to, then an unclean reboot happens. Result - there are 2
+ * physical eraseblocks P and P1 corresponding to the same logical eraseblock
+ * L. But P1 has greater sequence number, so UBI picks P1 when it attaches the
+ * flash.
+ *
+ * 2. From time to time UBI moves logical eraseblocks to other physical
+ * eraseblocks for wear-leveling reasons. If, for example, UBI moves L from P
+ * to P1, and an unclean reboot happens before P is physically erased, there
+ * are two physical eraseblocks P and P1 corresponding to L and UBI has to
+ * select one of them when the flash is attached. The @sqnum field says which
+ * PEB is the original (obviously P will have lower @sqnum) and the copy. But
+ * it is not enough to select the physical eraseblock with the higher sequence
+ * number, because the unclean reboot could have happen in the middle of the
+ * copying process, so the data in P is corrupted. It is also not enough to
+ * just select the physical eraseblock with lower sequence number, because the
+ * data there may be old (consider a case if more data was added to P1 after
+ * the copying). Moreover, the unclean reboot may happen when the erasure of P
+ * was just started, so it result in unstable P, which is "mostly" OK, but
+ * still has unstable bits.
+ *
+ * UBI uses the @copy_flag field to indicate that this logical eraseblock is a
+ * copy. UBI also calculates data CRC when the data is moved and stores it at
+ * the @data_crc field of the copy (P1). So when UBI needs to pick one physical
+ * eraseblock of two (P or P1), the @copy_flag of the newer one (P1) is
+ * examined. If it is cleared, the situation* is simple and the newer one is
+ * picked. If it is set, the data CRC of the copy (P1) is examined. If the CRC
+ * checksum is correct, this physical eraseblock is selected (P1). Otherwise
+ * the older one (P) is selected.
+ *
+ * Note, there is an obsolete @leb_ver field which was used instead of @sqnum
+ * in the past. But it is not used anymore and we keep it in order to be able
+ * to deal with old UBI images. It will be removed at some point.
+ *
+ * There are 2 sorts of volumes in UBI: user volumes and internal volumes.
+ * Internal volumes are not seen from outside and are used for various internal
+ * UBI purposes. In this implementation there is only one internal volume - the
+ * layout volume. Internal volumes are the main mechanism of UBI extensions.
+ * For example, in future one may introduce a journal internal volume. Internal
+ * volumes have their own reserved range of IDs.
+ *
+ * The @compat field is only used for internal volumes and contains the "degree
+ * of their compatibility". It is always zero for user volumes. This field
+ * provides a mechanism to introduce UBI extensions and to be still compatible
+ * with older UBI binaries. For example, if someone introduced a journal in
+ * future, he would probably use %UBI_COMPAT_DELETE compatibility for the
+ * journal volume. And in this case, older UBI binaries, which know nothing
+ * about the journal volume, would just delete this volume and work perfectly
+ * fine. This is similar to what Ext2fs does when it is fed by an Ext3fs image
+ * - it just ignores the Ext3fs journal.
+ *
+ * The @data_crc field contains the CRC checksum of the contents of the logical
+ * eraseblock if this is a static volume. In case of dynamic volumes, it does
+ * not contain the CRC checksum as a rule. The only exception is when the
+ * data of the physical eraseblock was moved by the wear-leveling unit, then
+ * the wear-leveling unit calculates the data CRC and stores it in the
+ * @data_crc field. And of course, the @copy_flag is %in this case.
+ *
+ * The @data_size field is used only for static volumes because UBI has to know
+ * how many bytes of data are stored in this eraseblock. For dynamic volumes,
+ * this field usually contains zero. The only exception is when the data of the
+ * physical eraseblock was moved to another physical eraseblock for
+ * wear-leveling reasons. In this case, UBI calculates CRC checksum of the
+ * contents and uses both @data_crc and @data_size fields. In this case, the
+ * @data_size field contains data size.
+ *
+ * The @used_ebs field is used only for static volumes and indicates how many
+ * eraseblocks the data of the volume takes. For dynamic volumes this field is
+ * not used and always contains zero.
+ *
+ * The @data_pad is calculated when volumes are created using the alignment
+ * parameter. So, effectively, the @data_pad field reduces the size of logical
+ * eraseblocks of this volume. This is very handy when one uses block-oriented
+ * software (say, cramfs) on top of the UBI volume.
+ */
+struct ubi_vid_hdr {
+ ubi32_t magic;
+ uint8_t version;
+ uint8_t vol_type;
+ uint8_t copy_flag;
+ uint8_t compat;
+ ubi32_t vol_id;
+ ubi32_t lnum;
+ ubi32_t leb_ver; /* obsolete, to be removed, don't use */
+ ubi32_t data_size;
+ ubi32_t used_ebs;
+ ubi32_t data_pad;
+ ubi32_t data_crc;
+ uint8_t padding1[4];
+ ubi64_t sqnum;
+ uint8_t padding2[12];
+ ubi32_t hdr_crc;
+} __attribute__ ((packed));
+
+/* Internal UBI volumes count */
+#define UBI_INT_VOL_COUNT 1
+
+/*
+ * Starting ID of internal volumes. There is reserved room for 4096 internal
+ * volumes.
+ */
+#define UBI_INTERNAL_VOL_START (0x7FFFFFFF - 4096)
+
+/* The layout volume contains the volume table */
+
+#define UBI_LAYOUT_VOL_ID UBI_INTERNAL_VOL_START
+#define UBI_LAYOUT_VOLUME_EBS 2
+#define UBI_LAYOUT_VOLUME_NAME "layout volume"
+#define UBI_LAYOUT_VOLUME_COMPAT UBI_COMPAT_REJECT
+
+/* The maximum number of volumes per one UBI device */
+#define UBI_MAX_VOLUMES 128
+
+/* The maximum volume name length */
+#define UBI_VOL_NAME_MAX 127
+
+/* Size of the volume table record */
+#define UBI_VTBL_RECORD_SIZE sizeof(struct ubi_vtbl_record)
+
+/* Size of the volume table record without the ending CRC */
+#define UBI_VTBL_RECORD_SIZE_CRC (UBI_VTBL_RECORD_SIZE - sizeof(ubi32_t))
+
+/**
+ * struct ubi_vtbl_record - a record in the volume table.
+ * @reserved_pebs: how many physical eraseblocks are reserved for this volume
+ * @alignment: volume alignment
+ * @data_pad: how many bytes are unused at the end of the each physical
+ * eraseblock to satisfy the requested alignment
+ * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
+ * @upd_marker: if volume update was started but not finished
+ * @name_len: volume name length
+ * @name: the volume name
+ * @padding2: reserved, zeroes
+ * @crc: a CRC32 checksum of the record
+ *
+ * The volume table records are stored in the volume table, which is stored in
+ * the layout volume. The layout volume consists of 2 logical eraseblock, each
+ * of which contains a copy of the volume table (i.e., the volume table is
+ * duplicated). The volume table is an array of &struct ubi_vtbl_record
+ * objects indexed by the volume ID.
+ *
+ * If the size of the logical eraseblock is large enough to fit
+ * %UBI_MAX_VOLUMES records, the volume table contains %UBI_MAX_VOLUMES
+ * records. Otherwise, it contains as many records as it can fit (i.e., size of
+ * logical eraseblock divided by sizeof(struct ubi_vtbl_record)).
+ *
+ * The @upd_marker flag is used to implement volume update. It is set to %1
+ * before update and set to %0 after the update. So if the update operation was
+ * interrupted, UBI knows that the volume is corrupted.
+ *
+ * The @alignment field is specified when the volume is created and cannot be
+ * later changed. It may be useful, for example, when a block-oriented file
+ * system works on top of UBI. The @data_pad field is calculated using the
+ * logical eraseblock size and @alignment. The alignment must be multiple to the
+ * minimal flash I/O unit. If @alignment is 1, all the available space of
+ * the physical eraseblocks is used.
+ *
+ * Empty records contain all zeroes and the CRC checksum of those zeroes.
+ */
+struct ubi_vtbl_record {
+ ubi32_t reserved_pebs;
+ ubi32_t alignment;
+ ubi32_t data_pad;
+ uint8_t vol_type;
+ uint8_t upd_marker;
+ ubi16_t name_len;
+ uint8_t name[UBI_VOL_NAME_MAX+1];
+ uint8_t padding2[24];
+ ubi32_t crc;
+} __attribute__ ((packed));
+
+#endif /* !__UBI_HEADER_H__ */
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 02/20 take 4] UBI: user-space API header
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
2007-03-23 16:43 ` [PATCH 01/20 take 4] UBI: on-flash data structures header Artem Bityutskiy
@ 2007-03-23 16:43 ` Artem Bityutskiy
2007-03-23 16:43 ` [PATCH 03/20 take 4] UBI: kernel-space " Artem Bityutskiy
` (17 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:43 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 6015 bytes --]
diff -auNrp tmp-from/include/mtd/ubi-user.h tmp-to/include/mtd/ubi-user.h
--- tmp-from/include/mtd/ubi-user.h 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/include/mtd/ubi-user.h 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,161 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+#ifndef __UBI_USER_H__
+#define __UBI_USER_H__
+
+/*
+ * UBI volume creation
+ * ~~~~~~~~~~~~~~~~~~~
+ *
+ * UBI volumes are created via the %UBI_IOCMKVOL IOCTL command of UBI character
+ * device. A &struct ubi_mkvol_req object has to be properly filled and a
+ * pointer to it has to be passed to the IOCTL.
+ *
+ * UBI volume deletion
+ * ~~~~~~~~~~~~~~~~~~~
+ *
+ * To delete a volume, the %UBI_IOCRMVOL IOCTL command of the UBI character
+ * device should be used. A pointer to the 32-bit volume ID hast to be passed
+ * to the IOCTL.
+ *
+ * UBI volume re-size
+ * ~~~~~~~~~~~~~~~~~~
+ *
+ * To re-size a volume, the %UBI_IOCRSVOL IOCTL command of the UBI character
+ * device should be used. A &struct ubi_rsvol_req object has to be properly
+ * filled and a pointer to it has to be passed to the IOCTL.
+ *
+ * UBI volume update
+ * ~~~~~~~~~~~~~~~~~
+ *
+ * Volume update should be done via the %UBI_IOCVOLUP IOCTL command of the
+ * corresponding UBI volume character device. A pointer to a 64-bit update
+ * size should be passed to the IOCTL. After then, UBI expects user to write
+ * this number of bytes to the volume character device. The update is finished
+ * when the claimed number of bytes is passed. So, the volume update sequence
+ * is something like:
+ *
+ * fd = open("/dev/my_volume");
+ * ioctl(fd, UBI_IOCVOLUP, &image_size);
+ * write(fd, buf, image_size);
+ * close(fd);
+ */
+
+/*
+ * When a new volume is created, users may either specify the volume number they
+ * want to create or to let UBI automatically assign a volume number using this
+ * constant.
+ */
+#define UBI_VOL_NUM_AUTO (-1)
+
+/* Maximum volume name length */
+#define UBI_MAX_VOLUME_NAME 127
+
+/* IOCTL commands of UBI character devices */
+
+#define UBI_IOC_MAGIC 'o'
+
+/* Create an UBI volume */
+#define UBI_IOCMKVOL _IOW(UBI_IOC_MAGIC, 0, struct ubi_mkvol_req)
+/* Remove an UBI volume */
+#define UBI_IOCRMVOL _IOW(UBI_IOC_MAGIC, 1, int32_t)
+/* Re-size an UBI volume */
+#define UBI_IOCRSVOL _IOW(UBI_IOC_MAGIC, 2, struct ubi_rsvol_req)
+
+/* IOCTL commands of UBI volume character devices */
+
+#define UBI_VOL_IOC_MAGIC 'O'
+
+/* Start UBI volume update */
+#define UBI_IOCVOLUP _IOW(UBI_VOL_IOC_MAGIC, 0, int64_t)
+/* An eraseblock erasure command, used for debugging, disabled by default */
+#define UBI_IOCEBER _IOW(UBI_VOL_IOC_MAGIC, 1, int32_t)
+
+/*
+ * UBI volume type constants.
+ *
+ * @UBI_DYNAMIC_VOLUME: dynamic volume
+ * @UBI_STATIC_VOLUME: static volume
+ */
+enum {
+ UBI_DYNAMIC_VOLUME = 3,
+ UBI_STATIC_VOLUME = 4
+};
+
+/**
+ * struct ubi_mkvol_req - volume description data structure used in
+ * volume creation requests.
+ * @vol_id: volume number
+ * @alignment: volume alignment
+ * @bytes: volume size in bytes
+ * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
+ * @padding1: reserved for future, not used
+ * @name_len: volume name length
+ * @padding2: reserved for future, not used
+ * @name: volume name
+ *
+ * This structure is used by userspace programs when creating new volumes. The
+ * @used_bytes field is only necessary when creating static volumes.
+ *
+ * The @alignment field specifies the required alignment of the volume logical
+ * eraseblock. This means, that the size of logical eraseblocks will be aligned
+ * to this number, i.e.,
+ * (UBI device logical eraseblock size) mod (@alignment) = 0.
+ *
+ * To put it differently, the logical eraseblock of this volume may be slightly
+ * shortened in order to make it properly aligned. The alignment has to be
+ * multiple of the flash minimal input/output unit, or %1 to utilize the entire
+ * available space of logical eraseblocks.
+ *
+ * The @alignment field may be useful, for example, when one wants to maintain
+ * a block device on top of an UBI volume. In this case, it is desirable to fit
+ * an integer number of blocks in logical eraseblocks of this UBI volume. With
+ * alignment it is possible to update this volume using plane UBI volume image
+ * BLOBs, without caring about how to properly align them.
+ */
+struct ubi_mkvol_req {
+ int32_t vol_id;
+ int32_t alignment;
+ int64_t bytes;
+ int8_t vol_type;
+ int8_t padding1;
+ int16_t name_len;
+ int8_t padding2[4];
+ char name[UBI_MAX_VOLUME_NAME+1];
+} __attribute__ ((packed));
+
+/**
+ * struct ubi_rsvol_req - a data structure used in volume re-size requests.
+ * @vol_id: ID of the volume to re-size
+ * @bytes: new size of the volume in bytes
+ *
+ * Re-sizing is possible for both dynamic and static volumes. But while dynamic
+ * volumes may be re-sized arbitrarily, static volumes cannot be made to be
+ * smaller then the number of bytes they bear. To arbitrarily shrink a static
+ * volume, it must be wiped out first (by means of volume update operation with
+ * zero number of bytes).
+ */
+struct ubi_rsvol_req {
+ int64_t bytes;
+ int32_t vol_id;
+} __attribute__ ((packed));
+
+#endif /* __UBI_USER_H__ */
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 03/20 take 4] UBI: kernel-space API header
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
2007-03-23 16:43 ` [PATCH 01/20 take 4] UBI: on-flash data structures header Artem Bityutskiy
2007-03-23 16:43 ` [PATCH 02/20 take 4] UBI: user-space API header Artem Bityutskiy
@ 2007-03-23 16:43 ` Artem Bityutskiy
2007-03-23 16:43 ` [PATCH 04/20 take 4] UBI: internal header Artem Bityutskiy
` (16 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:43 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
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diff -auNrp tmp-from/include/linux/mtd/ubi.h tmp-to/include/linux/mtd/ubi.h
--- tmp-from/include/linux/mtd/ubi.h 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/include/linux/mtd/ubi.h 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,191 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+#ifndef __LINUX_UBI_H__
+#define __LINUX_UBI_H__
+
+#include <asm/ioctl.h>
+#include <linux/types.h>
+#include <mtd/ubi-user.h>
+
+/*
+ * enum ubi_data_type - UBI data type hint constants.
+ *
+ * UBI_DATA_LONGTERM: long-term data
+ * UBI_DATA_SHORTTERM: short-term data
+ * UBI_DATA_UNKNOWN: data persistence is unknown
+ *
+ * These constants are used when data is written to UBI volumes in order to
+ * help the UBI wear-leveling unit to find more appropriate physical
+ * eraseblocks.
+ */
+enum ubi_data_type {
+ UBI_DATA_LONGTERM = 1,
+ UBI_DATA_SHORTTERM,
+ UBI_DATA_UNKNOWN
+};
+
+/*
+ * enum ubi_open_mode - UBI volume open mode constants.
+ *
+ * UBI_READONLY: read-only mode
+ * UBI_READWRITE: read-write mode
+ * UBI_EXCLUSIVE: exclusive mode
+ */
+enum ubi_open_mode {
+ UBI_READONLY = 1,
+ UBI_READWRITE,
+ UBI_EXCLUSIVE
+};
+
+/**
+ * struct ubi_volume_info - UBI volume description data structure.
+ * @vol_id: volume ID
+ * @ubi_num: UBI device number this volume belongs to
+ * @size: how many physical eraseblocks are reserved for this volume
+ * @used_bytes: how many bytes of data this volume contains
+ * @used_ebs: how many physical eraseblocks of this volume actually contain any
+ * data
+ * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
+ * @corrupted: non-zero if the volume is corrupted (static volumes only)
+ * @upd_marker: non-zero if the volume has update marker set
+ * @alignment: volume alignment
+ * @usable_leb_size: how many bytes are available in logical eraseblocks of
+ * this volume
+ * @name_len: volume name length
+ * @name: volume name
+ * @cdev: UBI volume character device major and minor numbers
+ *
+ * The @corrupted flag is only relevant to static volumes and is always zero
+ * for dynamic ones. This is because UBI does not care about dynamic volume
+ * data protection and only cares about protecting static volume data.
+ *
+ * The @upd_marker flag is set if the volume update operation was interrupted.
+ * Before touching the volume data during the update operation, UBI first sets
+ * the update marker flag for this volume. If the volume update operation was
+ * further interrupted, the update marker indicates this. If the update marker
+ * is set, the contents of the volume is certainly damaged and a new volume
+ * update operation has to be started.
+ *
+ * To put it differently, @corrupted and @upd_marker fields have different
+ * semantics:
+ * o the @corrupted flag means that this static volume is corrupted for some
+ * reasons, but not because an interrupted volume update
+ * o the @upd_marker field means that the volume is damaged because of an
+ * interrupted update operation.
+ *
+ * I.e., the @corrupted flag is never set if the @upd_marker flag is set.
+ *
+ * The @used_bytes and @used_ebs fields are only really needed for static
+ * volumes and contain the number of bytes stored in this static volume and how
+ * many eraseblock this data occupies. In case of dynamic volumes, the
+ * @used_bytes field is equivalent to @size*@usable_leb_size, and the @used_ebs
+ * field is equivalent to @size.
+ *
+ * In general, logical eraseblock size is a property of the UBI device, not
+ * of the UBI volume. Indeed, the logical eraseblock size depends on the
+ * physical eraseblock size and on how much bytes UBI headers consume. But
+ * because of the volume alignment (@alignment), the usable size of logical
+ * eraseblocks if a volume may be less. The following equation is true:
+ * @usable_leb_size = LEB size - (LEB size mod @alignment),
+ * where LEB size is the logical eraseblock size defined by the UBI device.
+ *
+ * The alignment is multiple to the minimal flash input/output unit size or %1
+ * if all the available space is used.
+ *
+ * To put this differently, alignment may be considered is a way to change
+ * volume logical eraseblock sizes.
+ */
+struct ubi_volume_info {
+ int ubi_num;
+ int vol_id;
+ int size;
+ long long used_bytes;
+ int used_ebs;
+ int vol_type;
+ int corrupted;
+ int upd_marker;
+ int alignment;
+ int usable_leb_size;
+ int name_len;
+ const char *name;
+ dev_t cdev;
+};
+
+/**
+ * struct ubi_device_info - UBI device description data structure.
+ * @ubi_num: ubi device number
+ * @leb_size: logical eraseblock size on this UBI device
+ * @min_io_size: minimal I/O unit size
+ * @ro_mode: if this device is in read-only mode
+ * @cdev: UBI character device major and minor numbers
+ *
+ * Note, @leb_size is the logical eraseblock size offered by the UBI device.
+ * Volumes of this UBI device may have smaller logical eraseblock size if their
+ * alignment is not equivalent to %1.
+ */
+struct ubi_device_info {
+ int ubi_num;
+ int leb_size;
+ int min_io_size;
+ int ro_mode;
+ dev_t cdev;
+};
+
+/* UBI descriptor given to users when they open UBI volumes */
+struct ubi_volume_desc;
+
+int ubi_get_device_info(int ubi_num, struct ubi_device_info *di);
+void ubi_get_volume_info(struct ubi_volume_desc *desc,
+ struct ubi_volume_info *vi);
+struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode);
+struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name,
+ int mode);
+void ubi_close_volume(struct ubi_volume_desc *desc);
+int ubi_eraseblock_read(struct ubi_volume_desc *desc, int lnum, char *buf,
+ int offset, int len, int check);
+int ubi_eraseblock_write(struct ubi_volume_desc *desc, int lnum,
+ const void *buf, int offset, int len, int dtype);
+int ubi_eraseblock_erase(struct ubi_volume_desc *desc, int lnum);
+int ubi_eraseblock_unmap(struct ubi_volume_desc *desc, int lnum);
+int ubi_eraseblock_is_mapped(struct ubi_volume_desc *desc, int lnum);
+
+/*
+ * This function is the same as the 'ubi_eraseblock_read()' function, but it
+ * does not provide the checking capability.
+ */
+static inline int ubi_read(struct ubi_volume_desc *desc, int lnum, char *buf,
+ int offset, int len)
+{
+ return ubi_eraseblock_read(desc, lnum, buf, offset, len, 0);
+}
+
+/*
+ * This function is the same as the 'ubi_eraseblock_write()' functions, but it
+ * does not have the data type argument.
+ */
+static inline int ubi_write(struct ubi_volume_desc *desc, int lnum,
+ const void *buf, int offset, int len)
+{
+ return ubi_eraseblock_write(desc, lnum, buf, offset, len,
+ UBI_DATA_UNKNOWN);
+}
+
+#endif /* !__LINUX_UBI_H__ */
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 04/20 take 4] UBI: internal header
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (2 preceding siblings ...)
2007-03-23 16:43 ` [PATCH 03/20 take 4] UBI: kernel-space " Artem Bityutskiy
@ 2007-03-23 16:43 ` Artem Bityutskiy
2007-03-23 16:43 ` [PATCH 05/20 take 4] UBI: startup code Artem Bityutskiy
` (15 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:43 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 19058 bytes --]
diff -auNrp tmp-from/drivers/mtd/ubi/ubi.h tmp-to/drivers/mtd/ubi/ubi.h
--- tmp-from/drivers/mtd/ubi/ubi.h 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/ubi.h 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,560 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ * Copyright (c) Nokia Corporation, 2006, 2007
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+#ifndef __UBI_UBI_H__
+#define __UBI_UBI_H__
+
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/rbtree.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/mutex.h>
+#include <linux/rwsem.h>
+#include <linux/spinlock.h>
+#include <linux/fs.h>
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/string.h>
+#include <linux/mtd/mtd.h>
+
+#include <mtd/ubi-header.h>
+#include <linux/mtd/ubi.h>
+
+#include "scan.h"
+#include "debug.h"
+
+/* Maximum number of supported UBI devices */
+#define UBI_MAX_DEVICES 32
+
+/* UBI name used for character devices, sysfs, etc */
+#define UBI_NAME_STR "ubi"
+
+/* Normal UBI messages */
+#define ubi_msg(fmt, ...) printk(KERN_NOTICE "UBI: " fmt "\n", ##__VA_ARGS__)
+/* UBI warning messages */
+#define ubi_warn(fmt, ...) printk(KERN_WARNING "UBI warning: %s: " fmt "\n", \
+ __FUNCTION__, ##__VA_ARGS__)
+/* UBI error messages */
+#define ubi_err(fmt, ...) printk(KERN_ERR "UBI error: %s: " fmt "\n", \
+ __FUNCTION__, ##__VA_ARGS__)
+
+/* Lowest number PEBs reserved for bad PEB handling */
+#define MIN_RESEVED_PEBS 2
+
+/* Background thread name pattern */
+#define UBI_BGT_NAME_PATTERN "ubi_bgt%dd"
+
+/* This marker in the EBA table means that the LEB is um-mapped */
+#define UBI_LEB_UNMAPPED -1
+
+/*
+ * In case of errors, UBI tries to repeat the operation several times before
+ * returning error. The below constant defines how many times UBI re-tries.
+ */
+#define UBI_IO_RETRIES 3
+
+/*
+ * Error codes returned by the I/O unit.
+ *
+ * UBI_IO_PEB_EMPTY: the physical eraseblock is empty, i.e. it contains only
+ * 0xFF bytes
+ * UBI_IO_PEB_FREE: the physical eraseblock is free, i.e. it contains only a
+ * valid erase counter header, and the rest are %0xFF bytes
+ * UBI_IO_BAD_EC_HDR: the erase counter header is corrupted (bad magic or CRC)
+ * UBI_IO_BAD_VID_HDR: the volume identifier header is corrupted (bad magic or
+ * CRC)
+ * UBI_IO_BITFLIPS: bit-flips were detected and corrected
+ */
+enum {
+ UBI_IO_PEB_EMPTY = 1,
+ UBI_IO_PEB_FREE,
+ UBI_IO_BAD_EC_HDR,
+ UBI_IO_BAD_VID_HDR,
+ UBI_IO_BITFLIPS
+};
+
+extern int ubi_devices_cnt;
+extern struct ubi_device *ubi_devices[];
+
+struct ubi_volume_desc;
+
+/**
+ * struct ubi_volume - UBI volume description data structure.
+ * @dev: device object to make use of the the Linux device model
+ * @cdev: character device object to create character device
+ * @ubi: reference to the UBI device description object
+ * @vol_id: volume ID
+ * @readers: number of users holding this volume in read-only mode
+ * @writers: number of users holding this volume in read-write mode
+ * @exclusive: whether somebody holds this volume in exclusive mode
+ * @removed: if the volume was removed
+ * @checked: if this static volume was checked
+ *
+ * @reserved_pebs: how many physical eraseblocks are reserved for this volume
+ * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
+ * @usable_leb_size: logical eraseblock size without padding
+ * @used_ebs: how many logical eraseblocks in this volume contain data
+ * @last_eb_bytes: how many bytes are stored in the last logical eraseblock
+ * @used_bytes: how many bytes of data this volume contains
+ * @upd_marker: non-zero if the update marker is set for this volume
+ * @corrupted: non-zero if the volume is corrupted (static volumes only)
+ * @alignment: volume alignment
+ * @data_pad: how many bytes are not used at the end of physical eraseblocks to
+ * satisfy the requested alignment
+ * @name_len: volume name length
+ * @name: volume name
+ *
+ * @updating: whether the volume is being updated
+ * @upd_ebs: how many eraseblocks are expected to be updated
+ * @upd_bytes: how many bytes are expected to be received
+ * @upd_received: how many update bytes were already received
+ * @upd_buf: update buffer which is used to collect update data
+ *
+ * @eba_tbl: EBA table of this volume (LEB->PEB mapping)
+ *
+ * @gluebi_desc: gluebi UBI volume descriptor
+ * @gluebi_refcount: reference count of the gluebi MTD device
+ * @gluebi_mtd: MTD device description object of the gluebi MTD device
+ *
+ * The @corrupted field indicates that the volume's contents is corrupted.
+ * Since UBI protects only static volumes, this field is not relevant to
+ * dynamic volumes - it is user's responsibility to assure their data
+ * integrity.
+ *
+ * The @upd_marker flag indicates that this volume is either being updated at
+ * the moment or is damaged because of an unclean reboot.
+ */
+struct ubi_volume {
+ struct device dev;
+ struct cdev cdev;
+ struct ubi_device *ubi;
+ int vol_id;
+ int readers;
+ int writers;
+ int exclusive;
+ int removed;
+ int checked;
+
+ int reserved_pebs;
+ int vol_type;
+ int usable_leb_size;
+ int used_ebs;
+ int last_eb_bytes;
+ long long used_bytes;
+ int upd_marker;
+ int corrupted;
+ int alignment;
+ int data_pad;
+ int name_len;
+ char name[UBI_VOL_NAME_MAX+1];
+
+ int updating;
+ int upd_ebs;
+ long long upd_bytes;
+ long long upd_received;
+ void *upd_buf;
+
+ int *eba_tbl;
+
+#ifdef CONFIG_MTD_UBI_GLUEBI
+ /* Gluebi-related stuff may be compiled out */
+ struct ubi_volume_desc *gluebi_desc;
+ int gluebi_refcount;
+ struct mtd_info gluebi_mtd;
+#endif
+};
+
+/**
+ * struct ubi_volume_desc - descriptor of the UBI volume returned when it is
+ * opened.
+ * @vol: reference to the corresponding volume description object
+ * @mode: open mode (%UBI_READONLY, %UBI_READWRITE, or %UBI_EXCLUSIVE)
+ */
+struct ubi_volume_desc {
+ struct ubi_volume *vol;
+ int mode;
+};
+
+struct ubi_wl_entry;
+
+/**
+ * struct ubi_device - UBI device description structure
+ * @dev: class device object to use the the Linux device model
+ * @cdev: character device object to create character device
+ * @ubi_num: UBI device number
+ * @ubi_name: UBI device name
+ * @major: character device major number
+ * @vol_count: number of volumes in this UBI device
+ * @volumes: volumes of this UBI device
+ * @volumes_lock: protects @volumes, @rsvd_pebs, @avail_pebs, beb_rsvd_pebs,
+ * @beb_rsvd_level, @bad_peb_count, @good_peb_count, @vol_count, @vol->readers,
+ * @vol->writers, @vol->exclusive, @vol->removed, @vol->mapping and
+ * @vol->eba_tbl.
+ *
+ * @rsvd_pebs: count of reserved physical eraseblocks
+ * @avail_pebs: count of available physical eraseblocks
+ * @beb_rsvd_pebs: how many physical eraseblocks are reserved for bad PEB
+ * handling
+ * @beb_rsvd_level: normal level of PEBs reserved for bad PEB handling
+ *
+ * @vtbl_slots: how many slots are available in the volume table
+ * @vtbl_size: size of the volume table in bytes
+ * @vtbl: in-RAM volume table copy
+ *
+ * @max_ec: current highest erase counter value
+ * @mean_ec: current mean erase counter value
+ *
+ * global_sqnum: global sequence number
+ * @ltree_lock: protects the lock tree and @global_sqnum
+ * @ltree: the lock tree
+ * @vtbl_mutex: protects on-flash volume table
+ *
+ * @used: RB-tree of used physical eraseblocks
+ * @free: RB-tree of free physical eraseblocks
+ * @scrub: RB-tree of physical eraseblocks which need scrubbing
+ * @prot: protection trees
+ * @prot.pnum: protection tree indexed by physical eraseblock numbers
+ * @prot.aec: protection tree indexed by absolute erase counter value
+ * @wl_lock: protects the @used, @free, @prot, @lookuptbl, @abs_ec, @move_from,
+ * @move_to, @move_to_put @erase_pending, @wl_scheduled, and @works
+ * fields
+ * @wl_scheduled: non-zero if the wear-leveling was scheduled
+ * @lookuptbl: a table to quickly find a &struct ubi_wl_entry object for any
+ * physical eraseblock
+ * @abs_ec: absolute erase counter
+ * @move_from: physical eraseblock from where the data is being moved
+ * @move_to: physical eraseblock where the data is being moved to
+ * @move_from_put: if the "from" PEB was put
+ * @move_to_put: if the "to" PEB was put
+ * @works: list of pending works
+ * @works_count: count of pending works
+ * @bgt_thread: background thread description object
+ * @thread_enabled: if the background thread is enabled
+ * @bgt_name: background thread name
+ *
+ * @flash_size: underlying MTD device size (in bytes)
+ * @peb_count: count of physical eraseblocks on the MTD device
+ * @peb_size: physical eraseblock size
+ * @bad_peb_count: count of bad physical eraseblocks
+ * @good_peb_count: count of good physical eraseblocks
+ * @min_io_size: minimal input/output unit size of the underlying MTD device
+ * @hdrs_min_io_size: minimal I/O unit size used for VID and EC headers
+ * @ro_mode: if the UBI device is in read-only mode
+ * @leb_size: logical eraseblock size
+ * @leb_start: starting offset of logical eraseblocks within physical
+ * eraseblocks
+ * @ec_hdr_alsize: size of the EC header aligned to @hdrs_min_io_size
+ * @vid_hdr_alsize: size of the VID header aligned to @hdrs_min_io_size
+ * @vid_hdr_offset: starting offset of the volume identifier header (might be
+ * unaligned)
+ * @vid_hdr_aloffset: starting offset of the VID header aligned to
+ * @hdrs_min_io_size
+ * @vid_hdr_shift: contains @vid_hdr_offset - @vid_hdr_aloffset
+ * @bad_allowed: whether the MTD device admits of bad physical eraseblocks or
+ * not
+ * @mtd: MTD device descriptor
+ */
+struct ubi_device {
+ struct cdev cdev;
+ struct device dev;
+ int ubi_num;
+ char ubi_name[sizeof(UBI_NAME_STR)+5];
+ int major;
+ int vol_count;
+ struct ubi_volume *volumes[UBI_MAX_VOLUMES+UBI_INT_VOL_COUNT];
+ spinlock_t volumes_lock;
+
+ int rsvd_pebs;
+ int avail_pebs;
+ int beb_rsvd_pebs;
+ int beb_rsvd_level;
+
+ int vtbl_slots;
+ int vtbl_size;
+ struct ubi_vtbl_record *vtbl;
+ struct mutex vtbl_mutex;
+
+ int max_ec;
+ int mean_ec;
+
+ /* EBA unit's stuff */
+ unsigned long long global_sqnum;
+ spinlock_t ltree_lock;
+ struct rb_root ltree;
+
+ /* Wear-leveling unit's stuff */
+ struct rb_root used;
+ struct rb_root free;
+ struct rb_root scrub;
+ struct {
+ struct rb_root pnum;
+ struct rb_root aec;
+ } prot;
+ spinlock_t wl_lock;
+ int wl_scheduled;
+ struct ubi_wl_entry **lookuptbl;
+ unsigned long long abs_ec;
+ struct ubi_wl_entry *move_from;
+ struct ubi_wl_entry *move_to;
+ int move_from_put;
+ int move_to_put;
+ struct list_head works;
+ int works_count;
+ struct task_struct *bgt_thread;
+ int thread_enabled;
+ char bgt_name[sizeof(UBI_BGT_NAME_PATTERN)+2];
+
+ /* I/O unit's stuff */
+ long long flash_size;
+ int peb_count;
+ int peb_size;
+ int bad_peb_count;
+ int good_peb_count;
+ int min_io_size;
+ int hdrs_min_io_size;
+ int ro_mode;
+ int leb_size;
+ int leb_start;
+ int ec_hdr_alsize;
+ int vid_hdr_alsize;
+ int vid_hdr_offset;
+ int vid_hdr_aloffset;
+ int vid_hdr_shift;
+ int bad_allowed;
+ struct mtd_info *mtd;
+};
+
+extern struct file_operations ubi_cdev_operations;
+extern struct file_operations ubi_vol_cdev_operations;
+extern struct class *ubi_class;
+
+/* vtbl.c */
+int ubi_change_vtbl_record(struct ubi_device *ubi, int idx,
+ struct ubi_vtbl_record *vtbl_rec);
+int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_scan_info *si);
+
+/* vmt.c */
+int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req);
+int ubi_remove_volume(struct ubi_volume_desc *desc);
+int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs);
+int ubi_add_volume(struct ubi_device *ubi, int vol_id);
+void ubi_free_volume(struct ubi_device *ubi, int vol_id);
+
+/* upd.c */
+int ubi_start_update(struct ubi_device *ubi, int vol_id, long long bytes);
+int ubi_more_update_data(struct ubi_device *ubi, int vol_id,
+ const void __user *buf, int count);
+
+/* misc.c */
+int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf, int length);
+int ubi_check_volume(struct ubi_device *ubi, int vol_id);
+void ubi_calculate_reserved(struct ubi_device *ubi);
+
+/* gluebi.c */
+#ifdef CONFIG_MTD_UBI_GLUEBI
+int ubi_create_gluebi(struct ubi_device *ubi, struct ubi_volume *vol);
+int ubi_destroy_gluebi(struct ubi_volume *vol);
+#else
+#define ubi_create_gluebi(ubi, vol) 0
+#define ubi_destroy_gluebi(vol) 0
+#endif
+
+/* eba.c */
+int ubi_eba_unmap_leb(struct ubi_device *ubi, int vol_id, int lnum);
+int ubi_eba_read_leb(struct ubi_device *ubi, int vol_id, int lnum, void *buf,
+ int offset, int len, int check);
+int ubi_eba_write_leb(struct ubi_device *ubi, int vol_id, int lnum,
+ const void *buf, int offset, int len,
+ enum ubi_data_type dtype);
+int ubi_eba_write_leb_st(struct ubi_device *ubi, int vol_id, int lnum,
+ const void *buf, int len, enum ubi_data_type dtype,
+ int used_ebs);
+int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
+ struct ubi_vid_hdr *vid_hdr);
+int ubi_eba_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si);
+void ubi_eba_close(const struct ubi_device *ubi);
+
+/* wl.c */
+int ubi_wl_get_peb(struct ubi_device *ubi, enum ubi_data_type dtype);
+int ubi_wl_put_peb(struct ubi_device *ubi, int pnum, int torture);
+int ubi_wl_flush(struct ubi_device *ubi);
+int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum);
+int ubi_wl_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si);
+void ubi_wl_close(struct ubi_device *ubi);
+
+/* io.c */
+int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset,
+ int len);
+int ubi_io_write(const struct ubi_device *ubi, const void *buf, int pnum,
+ int offset, int len);
+int ubi_io_sync_erase(const struct ubi_device *ubi, int pnum, int torture);
+int ubi_io_is_bad(const struct ubi_device *ubi, int pnum);
+int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum);
+int ubi_io_read_ec_hdr(const struct ubi_device *ubi, int pnum,
+ struct ubi_ec_hdr *ec_hdr, int verbose);
+int ubi_io_write_ec_hdr(const struct ubi_device *ubi, int pnum,
+ struct ubi_ec_hdr *ec_hdr);
+int ubi_io_read_vid_hdr(const struct ubi_device *ubi, int pnum,
+ struct ubi_vid_hdr *vid_hdr, int verbose);
+int ubi_io_write_vid_hdr(const struct ubi_device *ubi, int pnum,
+ struct ubi_vid_hdr *vid_hdr);
+
+/*
+ * ubi_rb_for_each_entry - walk an RB-tree.
+ * @rb: a pointer to type 'struct rb_node' to to use as a loop counter
+ * @pos: a pointer to RB-tree entry type to use as a loop counter
+ * @root: RB-tree's root
+ * @member: the name of the 'struct rb_node' within the RB-tree entry
+ */
+#define ubi_rb_for_each_entry(rb, pos, root, member) \
+ for (rb = rb_first(root), \
+ pos = (rb ? container_of(rb, typeof(*pos), member) : NULL); \
+ rb; \
+ rb = rb_next(rb), pos = container_of(rb, typeof(*pos), member))
+
+/**
+ * ubi_align_up - align an integer to another integer.
+ * @x: the integer to align
+ * @y: the integer to align to
+ *
+ * This function returns the lowest number which is multiple to @y and not less
+ * then @x.
+ */
+static inline int ubi_align_up(int x, int y)
+{
+ return y*(x/y) + (!!(x % y)) * y;
+}
+
+/**
+ * ubi_align_down - align an integer to another integer.
+ * @x: the integer to align
+ * @y: the integer to align to
+ *
+ * This function returns the highest number which is multiple to @y and not
+ * greater then @x.
+ */
+static inline int ubi_align_down(int x, int y)
+{
+ return y*(x/y);
+}
+
+/**
+ * ubi_zalloc_vid_hdr - allocate a volume identifier header object.
+ * @ubi: UBI device description object
+ *
+ * This function returns a pointer to the newly allocated and zero-filled
+ * volume identifier header object in case of success and %NULL in case of
+ * failure.
+ */
+static inline struct ubi_vid_hdr *ubi_zalloc_vid_hdr(const struct ubi_device *ubi)
+{
+ void *vid_hdr;
+
+ vid_hdr = kzalloc(ubi->vid_hdr_alsize, GFP_KERNEL);
+ if (unlikely(!vid_hdr))
+ return NULL;
+
+ /*
+ * VID headers may be stored at un-aligned flash offsets, so we shift
+ * the pointer.
+ */
+ return vid_hdr + ubi->vid_hdr_shift;
+}
+
+/**
+ * ubi_free_vid_hdr - free a volume identifier header object.
+ * @ubi: UBI device description object
+ * @vid_hdr: the object to free
+ */
+static inline void ubi_free_vid_hdr(const struct ubi_device *ubi,
+ struct ubi_vid_hdr *vid_hdr)
+{
+ void *p = vid_hdr;
+
+ if (unlikely(!p))
+ return;
+
+ kfree(p - ubi->vid_hdr_shift);
+}
+
+/*
+ * This function is equivalent to 'ubi_io_read()', but @offset is relative to
+ * the beginning of the logical eraseblock, not to the beginning of the
+ * physical eraseblock.
+ */
+static inline int ubi_io_read_data(const struct ubi_device *ubi, void *buf,
+ int pnum, int offset, int len)
+{
+ ubi_assert(offset >= 0);
+ return ubi_io_read(ubi, buf, pnum, offset + ubi->leb_start, len);
+}
+
+/*
+ * This function is equivalent to 'ubi_io_write()', but @offset is relative to
+ * the beginning of the logical eraseblock, not to the beginning of the
+ * physical eraseblock.
+ */
+static inline int ubi_io_write_data(const struct ubi_device *ubi, const void *buf,
+ int pnum, int offset, int len)
+{
+ ubi_assert(offset >= 0);
+ return ubi_io_write(ubi, buf, pnum, offset + ubi->leb_start, len);
+}
+
+/**
+ * ubi_ro_mode - switch to read-only mode.
+ * @ubi: UBI device description object
+ */
+static inline void ubi_ro_mode(struct ubi_device *ubi)
+{
+ ubi->ro_mode = 1;
+ ubi_warn("switch to read-only mode");
+}
+
+/**
+ * vol_id2idx - get table index by volume ID.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ */
+static inline int vol_id2idx(const struct ubi_device *ubi, int vol_id)
+{
+ if (vol_id >= UBI_INTERNAL_VOL_START)
+ return vol_id - UBI_INTERNAL_VOL_START + ubi->vtbl_slots;
+ else
+ return vol_id;
+}
+
+/**
+ * idx2vol_id - get volume ID by table index.
+ * @ubi: UBI device description object
+ * @idx: table index
+ */
+static inline int idx2vol_id(const struct ubi_device *ubi, int idx)
+{
+ if (idx >= ubi->vtbl_slots)
+ return idx - ubi->vtbl_slots + UBI_INTERNAL_VOL_START;
+ else
+ return idx;
+}
+
+#endif /* !__UBI_UBI_H__ */
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 05/20 take 4] UBI: startup code
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (3 preceding siblings ...)
2007-03-23 16:43 ` [PATCH 04/20 take 4] UBI: internal header Artem Bityutskiy
@ 2007-03-23 16:43 ` Artem Bityutskiy
2007-03-23 16:43 ` [PATCH 06/20 take 4] UBI: scanning unit Artem Bityutskiy
` (14 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:43 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 25560 bytes --]
diff -auNrp tmp-from/drivers/mtd/ubi/build.c tmp-to/drivers/mtd/ubi/build.c
--- tmp-from/drivers/mtd/ubi/build.c 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/build.c 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,843 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ * Copyright (c) Nokia Corporation, 2007
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём),
+ * Frank Haverkamp
+ */
+
+/*
+ * This file includes UBI initialization and building of UBI devices. At the
+ * moment UBI devices may only be added while UBI is initialized, but dynamic
+ * device add/remove functionality is planned. Also, at the moment we only
+ * attach UBI devices by scanning, which will become a bottleneck when flashes
+ * reach certain large size. Then one may improve UBI and add other methods.
+ */
+
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/stringify.h>
+#include <linux/stat.h>
+#include "ubi.h"
+
+/* Maximum length of the 'mtd=' parameter */
+#define MTD_PARAM_LEN_MAX 64
+
+/**
+ * struct mtd_dev_param - MTD device parameter description data structure.
+ * @name: MTD device name or number string
+ * @vid_hdr_offs: VID header offset
+ * @data_offs: data offset
+ */
+struct mtd_dev_param
+{
+ char name[MTD_PARAM_LEN_MAX];
+ int vid_hdr_offs;
+ int data_offs;
+};
+
+/* Numbers of elements set in the @mtd_dev_param array */
+static int mtd_devs = 0;
+
+/* MTD devices specification parameters */
+static struct mtd_dev_param mtd_dev_param[UBI_MAX_DEVICES];
+
+/* Number of UBI devices in system */
+int ubi_devices_cnt;
+
+/* All UBI devices in system */
+struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
+
+/* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
+struct class *ubi_class;
+
+/* "Show" method for files in '/<sysfs>/class/ubi/' */
+static ssize_t ubi_version_show(struct class *class, char *buf)
+{
+ return sprintf(buf, "%d\n", UBI_VERSION);
+}
+
+/* UBI version attribute ('/<sysfs>/class/ubi/version') */
+static struct class_attribute ubi_version =
+ __ATTR(version, S_IRUGO, ubi_version_show, NULL);
+
+static ssize_t dev_attribute_show(struct device *dev,
+ struct device_attribute *attr, char *buf);
+
+/* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
+static struct device_attribute dev_eraseblock_size =
+ __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
+static struct device_attribute dev_avail_eraseblocks =
+ __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
+static struct device_attribute dev_total_eraseblocks =
+ __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
+static struct device_attribute dev_volumes_count =
+ __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
+static struct device_attribute dev_max_ec =
+ __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
+static struct device_attribute dev_reserved_for_bad =
+ __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
+static struct device_attribute dev_bad_peb_count =
+ __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
+static struct device_attribute dev_max_vol_count =
+ __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
+static struct device_attribute dev_min_io_size =
+ __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
+static struct device_attribute dev_bgt_enabled =
+ __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
+
+/* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
+static ssize_t dev_attribute_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ const struct ubi_device *ubi;
+
+ ubi = container_of(dev, struct ubi_device, dev);
+ if (attr == &dev_eraseblock_size)
+ return sprintf(buf, "%d\n", ubi->leb_size);
+ else if (attr == &dev_avail_eraseblocks)
+ return sprintf(buf, "%d\n", ubi->avail_pebs);
+ else if (attr == &dev_total_eraseblocks)
+ return sprintf(buf, "%d\n", ubi->good_peb_count);
+ else if (attr == &dev_volumes_count)
+ return sprintf(buf, "%d\n", ubi->vol_count);
+ else if (attr == &dev_max_ec)
+ return sprintf(buf, "%d\n", ubi->max_ec);
+ else if (attr == &dev_reserved_for_bad)
+ return sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
+ else if (attr == &dev_bad_peb_count)
+ return sprintf(buf, "%d\n", ubi->bad_peb_count);
+ else if (attr == &dev_max_vol_count)
+ return sprintf(buf, "%d\n", ubi->vtbl_slots);
+ else if (attr == &dev_min_io_size)
+ return sprintf(buf, "%d\n", ubi->min_io_size);
+ else if (attr == &dev_bgt_enabled)
+ return sprintf(buf, "%d\n", ubi->thread_enabled);
+ else
+ BUG();
+
+ return 0;
+}
+
+/* Fake "release" method for UBI devices */
+static void dev_release(struct device *dev) { }
+
+/**
+ * ubi_sysfs_init - initialize sysfs for an UBI device.
+ * @ubi: UBI device description object
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int ubi_sysfs_init(struct ubi_device *ubi)
+{
+ int err;
+
+ ubi->dev.release = dev_release;
+ ubi->dev.devt = MKDEV(ubi->major, 0);
+ ubi->dev.class = ubi_class;
+ sprintf(&ubi->dev.bus_id[0], UBI_NAME_STR"%d", ubi->ubi_num);
+ err = device_register(&ubi->dev);
+ if (err)
+ goto out;
+
+ err = device_create_file(&ubi->dev, &dev_eraseblock_size);
+ if (err)
+ goto out_unregister;
+ err = device_create_file(&ubi->dev, &dev_avail_eraseblocks);
+ if (err)
+ goto out_eraseblock_size;
+ err = device_create_file(&ubi->dev, &dev_total_eraseblocks);
+ if (err)
+ goto out_avail_eraseblocks;
+ err = device_create_file(&ubi->dev, &dev_volumes_count);
+ if (err)
+ goto out_total_eraseblocks;
+ err = device_create_file(&ubi->dev, &dev_max_ec);
+ if (err)
+ goto out_volumes_count;
+ err = device_create_file(&ubi->dev, &dev_reserved_for_bad);
+ if (err)
+ goto out_volumes_max_ec;
+ err = device_create_file(&ubi->dev, &dev_bad_peb_count);
+ if (err)
+ goto out_reserved_for_bad;
+ err = device_create_file(&ubi->dev, &dev_max_vol_count);
+ if (err)
+ goto out_bad_peb_count;
+ err = device_create_file(&ubi->dev, &dev_min_io_size);
+ if (err)
+ goto out_max_vol_count;
+ err = device_create_file(&ubi->dev, &dev_bgt_enabled);
+ if (err)
+ goto out_min_io_size;
+
+ return 0;
+
+out_min_io_size:
+ device_remove_file(&ubi->dev, &dev_min_io_size);
+out_max_vol_count:
+ device_remove_file(&ubi->dev, &dev_max_vol_count);
+out_bad_peb_count:
+ device_remove_file(&ubi->dev, &dev_bad_peb_count);
+out_reserved_for_bad:
+ device_remove_file(&ubi->dev, &dev_reserved_for_bad);
+out_volumes_max_ec:
+ device_remove_file(&ubi->dev, &dev_max_ec);
+out_volumes_count:
+ device_remove_file(&ubi->dev, &dev_volumes_count);
+out_total_eraseblocks:
+ device_remove_file(&ubi->dev, &dev_total_eraseblocks);
+out_avail_eraseblocks:
+ device_remove_file(&ubi->dev, &dev_avail_eraseblocks);
+out_eraseblock_size:
+ device_remove_file(&ubi->dev, &dev_eraseblock_size);
+out_unregister:
+ device_unregister(&ubi->dev);
+out:
+ ubi_err("failed to initialize sysfs for %s", ubi->ubi_name);
+ return err;
+}
+
+/**
+ * ubi_sysfs_close - close sysfs for an UBI device.
+ * @ubi: UBI device description object
+ */
+static void ubi_sysfs_close(struct ubi_device *ubi)
+{
+ device_remove_file(&ubi->dev, &dev_bgt_enabled);
+ device_remove_file(&ubi->dev, &dev_min_io_size);
+ device_remove_file(&ubi->dev, &dev_max_vol_count);
+ device_remove_file(&ubi->dev, &dev_bad_peb_count);
+ device_remove_file(&ubi->dev, &dev_reserved_for_bad);
+ device_remove_file(&ubi->dev, &dev_max_ec);
+ device_remove_file(&ubi->dev, &dev_volumes_count);
+ device_remove_file(&ubi->dev, &dev_total_eraseblocks);
+ device_remove_file(&ubi->dev, &dev_avail_eraseblocks);
+ device_remove_file(&ubi->dev, &dev_eraseblock_size);
+ device_unregister(&ubi->dev);
+}
+
+/**
+ * kill_volumes - destroy all volumes.
+ * @ubi: UBI device description object
+ */
+static void kill_volumes(struct ubi_device *ubi)
+{
+ int i;
+
+ for (i = 0; i < ubi->vtbl_slots; i++)
+ if (ubi->volumes[i])
+ ubi_free_volume(ubi, i);
+}
+
+/**
+ * uif_init - initialize user interfaces for an UBI device.
+ * @ubi: UBI device description object
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int uif_init(struct ubi_device *ubi)
+{
+ int i, err;
+ dev_t dev;
+
+ mutex_init(&ubi->vtbl_mutex);
+ spin_lock_init(&ubi->volumes_lock);
+
+ sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
+
+ /*
+ * Major numbers for the UBI character devices are allocated
+ * dynamically. Major numbers of volume character devices are
+ * equivalent to ones of the corresponding UBI character device. Minor
+ * numbers of UBI character devices are 0, while minor numbers of
+ * volume character devices start from 1. Thus, we allocate one major
+ * number and ubi->vtbl_slots + 1 minor numbers.
+ */
+ err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
+ if (err) {
+ ubi_err("cannot register UBI character devices");
+ return err;
+ }
+
+ cdev_init(&ubi->cdev, &ubi_cdev_operations);
+ ubi->major = MAJOR(dev);
+ dbg_msg("%s major is %u", ubi->ubi_name, ubi->major);
+ ubi->cdev.owner = THIS_MODULE;
+
+ dev = MKDEV(ubi->major, 0);
+ err = cdev_add(&ubi->cdev, dev, 1);
+ if (err) {
+ ubi_err("cannot add character device %s", ubi->ubi_name);
+ goto out_unreg;
+ }
+
+ err = ubi_sysfs_init(ubi);
+ if (err)
+ goto out_cdev;
+
+ for (i = 0; i < ubi->vtbl_slots; i++)
+ if (ubi->volumes[i]) {
+ err = ubi_add_volume(ubi, i);
+ if (err)
+ goto out_volumes;
+ }
+
+ return 0;
+
+out_volumes:
+ kill_volumes(ubi);
+ ubi_sysfs_close(ubi);
+out_cdev:
+ cdev_del(&ubi->cdev);
+out_unreg:
+ unregister_chrdev_region(MKDEV(ubi->major, 0),
+ ubi->vtbl_slots + 1);
+ return err;
+}
+
+/**
+ * uif_close - close user interfaces for an UBI device.
+ * @ubi: UBI device description object
+ */
+static void uif_close(struct ubi_device *ubi)
+{
+ kill_volumes(ubi);
+ ubi_sysfs_close(ubi);
+ cdev_del(&ubi->cdev);
+ unregister_chrdev_region(MKDEV(ubi->major, 0), ubi->vtbl_slots + 1);
+}
+
+/**
+ * attach_by_scanning - attach an MTD device using scanning method.
+ * @ubi: UBI device descriptor
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ *
+ * Note, currently this is the only method to attach UBI devices. Hopefully in
+ * the future we'll have more scalable attaching methods and avoid full media
+ * scanning. But even in this case scanning will be needed as a fall-back
+ * attaching method if there are some on-flash table corruptions.
+ */
+static int attach_by_scanning(struct ubi_device *ubi)
+{
+ int err;
+ struct ubi_scan_info *si;
+
+ si = ubi_scan(ubi);
+ if (IS_ERR(si))
+ return PTR_ERR(si);
+
+ ubi->bad_peb_count = si->bad_peb_count;
+ ubi->good_peb_count = ubi->peb_count - ubi->bad_peb_count;
+ ubi->max_ec = si->max_ec;
+ ubi->mean_ec = si->mean_ec;
+
+ err = ubi_read_volume_table(ubi, si);
+ if (err)
+ goto out_si;
+
+ err = ubi_wl_init_scan(ubi, si);
+ if (err)
+ goto out_vtbl;
+
+ err = ubi_eba_init_scan(ubi, si);
+ if (err)
+ goto out_wl;
+
+ ubi_scan_destroy_si(si);
+ return 0;
+
+out_wl:
+ ubi_wl_close(ubi);
+out_vtbl:
+ kfree(ubi->vtbl);
+out_si:
+ ubi_scan_destroy_si(si);
+ return err;
+}
+
+/**
+ * io_init - initialize I/O unit for a given UBI device.
+ * @ubi: UBI device description object
+ *
+ * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
+ * assumed:
+ * o EC header is always at offset zero - this cannot be changed;
+ * o VID header starts just after the EC header at the closest address
+ * aligned to @io->@hdrs_min_io_size;
+ * o data starts just after the VID header at the closest address aligned to
+ * @io->@min_io_size
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int io_init(struct ubi_device *ubi)
+{
+ if (ubi->mtd->numeraseregions != 0) {
+ /*
+ * Some flashes have several erase regions. Different regions
+ * may have different eraseblock size and other
+ * characteristics. It looks like mostly multi-region flashes
+ * have one "main" region and one or more small regions to
+ * store boot loader code or boot parameters or whatever. I
+ * guess we should just pick the largest region. But this is
+ * not implemented.
+ */
+ ubi_err("multiple regions, not implemented");
+ return -EINVAL;
+ }
+
+ /*
+ * Note, in this implementation we support MTD devices with 0x7FFFFFFF
+ * physical eraseblocks maximum.
+ */
+
+ ubi->peb_size = ubi->mtd->erasesize;
+ ubi->peb_count = ubi->mtd->size / ubi->mtd->erasesize;
+ ubi->flash_size = ubi->mtd->size;
+
+ if (ubi->mtd->block_isbad && ubi->mtd->block_markbad)
+ ubi->bad_allowed = 1;
+
+ ubi->min_io_size = ubi->mtd->writesize;
+ ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
+
+ ubi_assert(ubi->hdrs_min_io_size > 0);
+ ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
+ ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
+
+ /* Calculate default aligned sizes of EC and VID headers */
+ ubi->ec_hdr_alsize = ubi_align_up(UBI_EC_HDR_SIZE,
+ ubi->hdrs_min_io_size);
+ ubi->vid_hdr_alsize = ubi_align_up(UBI_VID_HDR_SIZE,
+ ubi->hdrs_min_io_size);
+
+ dbg_msg("min_io_size %d", ubi->min_io_size);
+ dbg_msg("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
+ dbg_msg("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
+ dbg_msg("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
+
+ if (ubi->vid_hdr_offset == 0)
+ /* Default offset */
+ ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
+ ubi->ec_hdr_alsize;
+ else {
+ ubi->vid_hdr_aloffset = ubi_align_down(ubi->vid_hdr_offset,
+ ubi->hdrs_min_io_size);
+ ubi->vid_hdr_shift = ubi->vid_hdr_offset -
+ ubi->vid_hdr_aloffset;
+ }
+
+ /* Similar for the data offset */
+ if (ubi->leb_start == 0) {
+ ubi->leb_start = ubi->vid_hdr_offset + ubi->vid_hdr_alsize;
+ ubi->leb_start = ubi_align_up(ubi->leb_start, ubi->min_io_size);
+ }
+
+ dbg_msg("vid_hdr_offset %d", ubi->vid_hdr_offset);
+ dbg_msg("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
+ dbg_msg("vid_hdr_shift %d", ubi->vid_hdr_shift);
+ dbg_msg("leb_start %d", ubi->leb_start);
+
+ /* The shift must be aligned to 32-bit boundary */
+ if (ubi->vid_hdr_shift % 4) {
+ ubi_err("unaligned VID header shift %d",
+ ubi->vid_hdr_shift);
+ return -EINVAL;
+ }
+
+ /* Check sanity */
+ if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
+ ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
+ ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
+ ubi->leb_start % ubi->min_io_size) {
+ ubi_err("bad VID header (%d) or data offsets (%d)",
+ ubi->vid_hdr_offset, ubi->leb_start);
+ return -EINVAL;
+ }
+
+ /*
+ * It may happen that EC and VID headers are situated in one minimal
+ * I/O unit. In this case we can only accept this UBI image in
+ * read-only mode.
+ */
+ if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
+ ubi_warn("EC and VID headers are in the same minimal I/O unit, "
+ "switch to read-only mode");
+ ubi->ro_mode = 1;
+ }
+
+ ubi->leb_size = ubi->peb_size - ubi->leb_start;
+
+ if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
+ ubi_msg("MTD device %d is write-protected, attach in "
+ "read-only mode", ubi->mtd->index);
+ ubi->ro_mode = 1;
+ }
+
+ dbg_msg("leb_size %d", ubi->leb_size);
+ dbg_msg("ro_mode %d", ubi->ro_mode);
+
+ /*
+ * Note, ideally, we have to initialize ubi->bad_peb_count here. But
+ * unfortunately, MTD does not provide this information. We should loop
+ * over all physical eraseblocks and invoke mtd->block_is_bad() for
+ * each physical eraseblock. So, we skip ubi->bad_peb_count
+ * uninitialized and initialize it after scanning.
+ */
+
+ return 0;
+}
+
+/**
+ * attach_mtd_dev - attach an MTD device.
+ * @mtd_dev: MTD device name or number string
+ * @vid_hdr_offset: VID header offset
+ * @data_offset: data offset
+ *
+ * This function attaches an MTD device to UBI. It first treats @mtd_dev as the
+ * MTD device name, and tries to open it by this name. If it is unable to open,
+ * it tries to convert @mtd_dev to an integer and open the MTD device by its
+ * number. Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int attach_mtd_dev(const char *mtd_dev, int vid_hdr_offset,
+ int data_offset)
+{
+ struct ubi_device *ubi;
+ struct mtd_info *mtd;
+ int i, err;
+
+ mtd = get_mtd_device_nm(mtd_dev);
+ if (IS_ERR(mtd)) {
+ int mtd_num;
+ char *endp;
+
+ if (PTR_ERR(mtd) != -ENODEV)
+ return PTR_ERR(mtd);
+
+ /*
+ * Probably this is not MTD device name but MTD device number -
+ * check this out.
+ */
+ mtd_num = simple_strtoul(mtd_dev, &endp, 0);
+ if (*endp != '\0' || mtd_dev == endp) {
+ ubi_err("incorrect MTD device: \"%s\"", mtd_dev);
+ return -ENODEV;
+ }
+
+ mtd = get_mtd_device(NULL, mtd_num);
+ if (IS_ERR(mtd))
+ return PTR_ERR(mtd);
+ }
+
+ /* Check if we already have the same MTD device attached */
+ for (i = 0; i < ubi_devices_cnt; i++)
+ if (ubi_devices[i]->mtd->index == mtd->index) {
+ ubi_err("mtd%d is already attached to ubi%d",
+ mtd->index, i);
+ err = -EINVAL;
+ goto out_mtd;
+ }
+
+ ubi = ubi_devices[ubi_devices_cnt] = kzalloc(sizeof(struct ubi_device),
+ GFP_KERNEL);
+ if (!ubi) {
+ err = -ENOMEM;
+ goto out_mtd;
+ }
+
+ ubi->ubi_num = ubi_devices_cnt;
+ ubi->mtd = mtd;
+
+ dbg_msg("attaching mtd%d to ubi%d: VID header offset %d data offset %d",
+ ubi->mtd->index, ubi_devices_cnt, vid_hdr_offset, data_offset);
+
+ ubi->vid_hdr_offset = vid_hdr_offset;
+ ubi->leb_start = data_offset;
+ err = io_init(ubi);
+ if (err)
+ goto out_free;
+
+ err = attach_by_scanning(ubi);
+ if (err) {
+ dbg_err("failed to attach by scanning, error %d", err);
+ goto out_free;
+ }
+
+ err = uif_init(ubi);
+ if (err)
+ goto out_detach;
+
+ ubi_devices_cnt += 1;
+
+ ubi_msg("attached mtd%d to ubi%d", ubi->mtd->index, ubi_devices_cnt);
+ ubi_msg("MTD device name: \"%s\"", ubi->mtd->name);
+ ubi_msg("MTD device size: %llu MiB", ubi->flash_size >> 20);
+ ubi_msg("physical eraseblock size: %d bytes (%d KiB)",
+ ubi->peb_size, ubi->peb_size >> 10);
+ ubi_msg("logical eraseblock size: %d bytes", ubi->leb_size);
+ ubi_msg("number of good PEBs: %d", ubi->good_peb_count);
+ ubi_msg("number of bad PEBs: %d", ubi->bad_peb_count);
+ ubi_msg("smallest flash I/O unit: %d", ubi->min_io_size);
+ ubi_msg("VID header offset: %d (aligned %d)",
+ ubi->vid_hdr_offset, ubi->vid_hdr_aloffset);
+ ubi_msg("data offset: %d", ubi->leb_start);
+ ubi_msg("max. allowed volumes: %d", ubi->vtbl_slots);
+ ubi_msg("wear-leveling threshold: %d", CONFIG_MTD_UBI_WL_THRESHOLD);
+ ubi_msg("number of internal volumes: %d", UBI_INT_VOL_COUNT);
+ ubi_msg("number of user volumes: %d",
+ ubi->vol_count - UBI_INT_VOL_COUNT);
+ ubi_msg("available PEBs: %d", ubi->avail_pebs);
+ ubi_msg("total number of reserved PEBs: %d", ubi->rsvd_pebs);
+ ubi_msg("number of PEBs reserved for bad PEB handling: %d",
+ ubi->beb_rsvd_pebs);
+ ubi_msg("max/mean erase counter: %d/%d", ubi->max_ec, ubi->mean_ec);
+
+ /* Enable the background thread */
+ if (!DBG_DISABLE_BGT) {
+ ubi->thread_enabled = 1;
+ wake_up_process(ubi->bgt_thread);
+ }
+
+ return 0;
+
+out_detach:
+ ubi_eba_close(ubi);
+ ubi_wl_close(ubi);
+ kfree(ubi->vtbl);
+out_free:
+ kfree(ubi);
+out_mtd:
+ put_mtd_device(mtd);
+ ubi_devices[ubi_devices_cnt] = NULL;
+ return err;
+}
+
+/**
+ * detach_mtd_dev - detach an MTD device.
+ * @ubi: UBI device description object
+ */
+static void detach_mtd_dev(struct ubi_device *ubi)
+{
+ int ubi_num = ubi->ubi_num, mtd_num = ubi->mtd->index;
+
+ dbg_msg("detaching mtd%d from ubi%d", ubi->mtd->index, ubi_num);
+ uif_close(ubi);
+ ubi_eba_close(ubi);
+ ubi_wl_close(ubi);
+ kfree(ubi->vtbl);
+ put_mtd_device(ubi->mtd);
+ kfree(ubi_devices[ubi_num]);
+ ubi_devices[ubi_num] = NULL;
+ ubi_devices_cnt -= 1;
+ ubi_assert(ubi_devices_cnt >= 0);
+ ubi_msg("mtd% is detached from ubi%d", mtd_num, ubi_num);
+}
+
+static int __init ubi_init(void)
+{
+ int err, i, k;
+
+ /* Ensure that EC and VID headers have correct size */
+ BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
+ BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
+
+ if (mtd_devs > UBI_MAX_DEVICES) {
+ printk("UBI error: too many MTD devices, maximum is %d\n",
+ UBI_MAX_DEVICES);
+ return -EINVAL;
+ }
+
+ ubi_class = class_create(THIS_MODULE, UBI_NAME_STR);
+ if (IS_ERR(ubi_class))
+ return PTR_ERR(ubi_class);
+
+ err = class_create_file(ubi_class, &ubi_version);
+ if (err)
+ goto out_class;
+
+ /* Attach MTD devices */
+ for (i = 0; i < mtd_devs; i++) {
+ struct mtd_dev_param *p = &mtd_dev_param[i];
+
+ cond_resched();
+
+ if (!p->name) {
+ dbg_err("empty name");
+ err = -EINVAL;
+ goto out_detach;
+ }
+
+ err = attach_mtd_dev(p->name, p->vid_hdr_offs, p->data_offs);
+ if (err)
+ goto out_detach;
+ }
+
+ return 0;
+
+out_detach:
+ for (k = 0; k < i; k++)
+ detach_mtd_dev(ubi_devices[k]);
+ class_remove_file(ubi_class, &ubi_version);
+out_class:
+ class_destroy(ubi_class);
+ return err;
+}
+module_init(ubi_init);
+
+static void __exit ubi_exit(void)
+{
+ int i, n = ubi_devices_cnt;
+
+ for (i = 0; i < n; i++)
+ detach_mtd_dev(ubi_devices[i]);
+ class_remove_file(ubi_class, &ubi_version);
+ class_destroy(ubi_class);
+}
+module_exit(ubi_exit);
+
+/**
+ * bytes_str_to_int - convert a string representing number of bytes to an
+ * integer.
+ * @str: the string to convert
+ *
+ * This function returns positive resulting integer in case of success and a
+ * negative error code in case of failure.
+ */
+static int __init bytes_str_to_int(const char *str)
+{
+ char *endp;
+ unsigned long result;
+
+ result = simple_strtoul(str, &endp, 0);
+ if (str == endp || result < 0) {
+ printk("UBI error: incorrect bytes count: \"%s\"\n", str);
+ return -EINVAL;
+ }
+
+ switch (*endp) {
+ case 'G':
+ result *= 1024;
+ case 'M':
+ result *= 1024;
+ case 'K':
+ case 'k':
+ result *= 1024;
+ if (endp[1] == 'i' && (endp[2] == '\0' ||
+ endp[2] == 'B' || endp[2] == 'b'))
+ endp += 2;
+ case '\0':
+ break;
+ default:
+ printk("UBI error: incorrect bytes count: \"%s\"\n", str);
+ return -EINVAL;
+ }
+
+ return result;
+}
+
+/**
+ * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
+ * @val: the parameter value to parse
+ * @kp: not used
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of error.
+ */
+static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
+{
+ int i, len;
+ struct mtd_dev_param *p;
+ char buf[MTD_PARAM_LEN_MAX];
+ char *pbuf = &buf[0];
+ char *tokens[3] = {NULL, NULL, NULL};
+
+ if (mtd_devs == UBI_MAX_DEVICES) {
+ printk("UBI error: too many parameters, max. is %d\n",
+ UBI_MAX_DEVICES);
+ return -EINVAL;
+ }
+
+ len = strnlen(val, MTD_PARAM_LEN_MAX);
+ if (len == MTD_PARAM_LEN_MAX) {
+ printk("UBI error: parameter \"%s\" is too long, max. is %d\n",
+ val, MTD_PARAM_LEN_MAX);
+ return -EINVAL;
+ }
+
+ if (len == 0) {
+ printk("UBI warning: empty 'mtd=' parameter - ignored\n");
+ return 0;
+ }
+
+ strcpy(buf, val);
+
+ /* Get rid of the final newline */
+ if (buf[len - 1] == '\n')
+ buf[len - 1] = 0;
+
+ for (i = 0; i < 3; i++)
+ tokens[i] = strsep(&pbuf, ",");
+
+ if (pbuf) {
+ printk("UBI error: too many arguments at \"%s\"\n", val);
+ return -EINVAL;
+ }
+
+ if (tokens[0] == '\0')
+ return -EINVAL;
+
+ p = &mtd_dev_param[mtd_devs];
+ strcpy(&p->name[0], tokens[0]);
+
+ if (tokens[1])
+ p->vid_hdr_offs = bytes_str_to_int(tokens[1]);
+ if (tokens[2])
+ p->data_offs = bytes_str_to_int(tokens[2]);
+
+ if (p->vid_hdr_offs < 0)
+ return p->vid_hdr_offs;
+ if (p->data_offs < 0)
+ return p->data_offs;
+
+ mtd_devs += 1;
+ return 0;
+}
+
+module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 000);
+MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: "
+ "mtd=<name|num>[,<vid_hdr_offs>,<data_offs>]. "
+ "Multiple \"mtd\" parameters may be specified.\n"
+ "MTD devices may be specified by their number or name. "
+ "Optional \"vid_hdr_offs\" and \"data_offs\" parameters "
+ "specify UBI VID header position and data starting "
+ "position to be used by UBI.\n"
+ "Example: mtd=content,1984,2048 mtd=4 - attach MTD device"
+ "with name content using VID header offset 1984 and data "
+ "start 2048, and MTD device number 4 using default "
+ "offsets");
+
+MODULE_VERSION(__stringify(UBI_VERSION));
+MODULE_DESCRIPTION("UBI - Unsorted Block Images");
+MODULE_AUTHOR("Artem Bityutskiy");
+MODULE_LICENSE("GPL");
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 06/20 take 4] UBI: scanning unit
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (4 preceding siblings ...)
2007-03-23 16:43 ` [PATCH 05/20 take 4] UBI: startup code Artem Bityutskiy
@ 2007-03-23 16:43 ` Artem Bityutskiy
2007-03-23 16:43 ` [PATCH 07/20 take 4] UBI: I/O unit Artem Bityutskiy
` (13 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:43 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 43397 bytes --]
diff -auNrp tmp-from/drivers/mtd/ubi/scan.c tmp-to/drivers/mtd/ubi/scan.c
--- tmp-from/drivers/mtd/ubi/scan.c 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/scan.c 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,1374 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * UBI scanning unit.
+ *
+ * This unit is responsible for scanning the flash media, checking UBI
+ * headers and providing complete information about the UBI flash image.
+ *
+ * The scanning information is reoresented by a &struct ubi_scan_info' object.
+ * Information about found volumes is represented by &struct ubi_scan_volume
+ * objects which are kept in volume RB-tree with root at the @volumes field.
+ * The RB-tree is indexed by the volume ID.
+ *
+ * Found logical eraseblocks are represented by &struct ubi_scan_leb objects.
+ * These objects are kept in per-volume RB-trees with the root at the
+ * corresponding &struct ubi_scan_volume object. To put it differently, we keep
+ * an RB-tree of per-volume objects and each of these objects is the root of
+ * RB-tree of per-eraseblock objects.
+ *
+ * Corrupted physical eraseblocks are put to the @corr list, free physical
+ * eraseblocks are put to the @free list and the physical eraseblock to be
+ * erased are put to the @erase list.
+ */
+
+#include <linux/err.h>
+#include <linux/crc32.h>
+#include "ubi.h"
+
+#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
+static int paranoid_check_si(const struct ubi_device *ubi,
+ struct ubi_scan_info *si);
+#else
+#define paranoid_check_si(ubi, si) 0
+#endif
+
+/* Temporary variables used during scanning */
+static struct ubi_ec_hdr *ech;
+static struct ubi_vid_hdr *vidh;
+
+int ubi_scan_add_to_list(struct ubi_scan_info *si, int pnum, int ec,
+ struct list_head *list)
+{
+ struct ubi_scan_leb *seb;
+
+ if (list == &si->free)
+ dbg_bld("add to free: PEB %d, EC %d", pnum, ec);
+ else if (list == &si->erase)
+ dbg_bld("add to erase: PEB %d, EC %d", pnum, ec);
+ else if (list == &si->corr)
+ dbg_bld("add to corrupted: PEB %d, EC %d", pnum, ec);
+ else if (list == &si->alien)
+ dbg_bld("add to alien: PEB %d, EC %d", pnum, ec);
+ else
+ BUG();
+
+ seb = kmalloc(sizeof(struct ubi_scan_leb), GFP_KERNEL);
+ if (unlikely(!seb))
+ return -ENOMEM;
+
+ seb->pnum = pnum;
+ seb->ec = ec;
+ list_add_tail(&seb->u.list, list);
+ return 0;
+}
+
+/**
+ * commit_to_mean_value - commit intermediate results to the final mean erase
+ * counter value.
+ * @si: scanning information
+ *
+ * This is a helper function which calculates partial mean erase counter mean
+ * value and adds it to the resulting mean value. As we can work only in
+ * integer arithmetic and we want to calculate the mean value of erase counter
+ * accurately, we first sum erase counter values in @si->ec_sum variable and
+ * count these components in @si->ec_count. If this temporary @si->ec_sum is
+ * going to overflow, we calculate the partial mean value
+ * (@si->ec_sum/@si->ec_count) and add it to @si->mean_ec.
+ */
+static void commit_to_mean_value(struct ubi_scan_info *si)
+{
+ si->ec_sum /= si->ec_count;
+ if (si->ec_sum % si->ec_count >= si->ec_count / 2)
+ si->mean_ec += 1;
+ si->mean_ec += si->ec_sum;
+}
+
+/**
+ * validate_vid_hdr - check that volume identifier header is correct and
+ * consistent.
+ * @vid_hdr: the volume identifier header to check
+ * @sv: information about the volume this logical eraseblock belongs to
+ * @pnum: physical eraseblock number the VID header came from
+ *
+ * This function checks that data stored in @vid_hdr is consistent. Returns
+ * non-zero if an inconsistency was found and zero if not.
+ *
+ * Note, UBI does sanity check of everything it reads from the flash media.
+ * Most of the checks are done in the I/O unit. Here we check that the
+ * information in the VID header is consistent to the information in other VID
+ * headers of the same volume.
+ */
+static int validate_vid_hdr(const struct ubi_vid_hdr *vid_hdr,
+ const struct ubi_scan_volume *sv, int pnum)
+{
+ int vol_type = vid_hdr->vol_type;
+ int vol_id = ubi32_to_cpu(vid_hdr->vol_id);
+ int used_ebs = ubi32_to_cpu(vid_hdr->used_ebs);
+ int data_pad = ubi32_to_cpu(vid_hdr->data_pad);
+
+ if (sv->leb_count != 0) {
+ int sv_vol_type;
+
+ /*
+ * This is not the first logical eraseblock belonging to this
+ * volume. Ensure that the data in its VID header is consistent
+ * to the data in previous logical eraseblock headers.
+ */
+
+ if (unlikely(vol_id != sv->vol_id)) {
+ dbg_err("inconsistent vol_id");
+ goto bad;
+ }
+
+ if (sv->vol_type == UBI_STATIC_VOLUME)
+ sv_vol_type = UBI_VID_STATIC;
+ else
+ sv_vol_type = UBI_VID_DYNAMIC;
+
+ if (unlikely(vol_type != sv_vol_type)) {
+ dbg_err("inconsistent vol_type");
+ goto bad;
+ }
+
+ if (unlikely(used_ebs != sv->used_ebs)) {
+ dbg_err("inconsistent used_ebs");
+ goto bad;
+ }
+
+ if (unlikely(data_pad != sv->data_pad)) {
+ dbg_err("inconsistent data_pad");
+ goto bad;
+ }
+ }
+
+ return 0;
+
+bad:
+ ubi_err("inconsistent VID header at PEB %d", pnum);
+ ubi_dbg_dump_vid_hdr(vid_hdr);
+ ubi_dbg_dump_sv(sv);
+ return -EINVAL;
+}
+
+/**
+ * add_volume - add volume to the scanning information.
+ * @si: scanning information
+ * @vol_id: ID of the volume to add
+ * @pnum: physical eraseblock number
+ * @vid_hdr: volume identifier header
+ *
+ * If the volume corresponding to the @vid_hdr logical eraseblock is already
+ * present in the scanning information, this function does nothing. Otherwise
+ * it adds corresponding volume to the scanning information. Returns a pointer
+ * to the scanning volume object in case of success and a negative error code
+ * in case of failure.
+ */
+static struct ubi_scan_volume *add_volume(struct ubi_scan_info *si, int vol_id,
+ int pnum,
+ const struct ubi_vid_hdr *vid_hdr)
+{
+ struct ubi_scan_volume *sv;
+ struct rb_node **p = &si->volumes.rb_node, *parent = NULL;
+
+ ubi_assert(vol_id == ubi32_to_cpu(vid_hdr->vol_id));
+
+ /* Walk the volume RB-tree to look if this volume is already present */
+ while (*p) {
+ parent = *p;
+ sv = rb_entry(parent, struct ubi_scan_volume, rb);
+
+ if (vol_id == sv->vol_id)
+ return sv;
+
+ if (vol_id > sv->vol_id)
+ p = &(*p)->rb_left;
+ else
+ p = &(*p)->rb_right;
+ }
+
+ /* The volume is absent - add it */
+ sv = kmalloc(sizeof(struct ubi_scan_volume), GFP_KERNEL);
+ if (unlikely(!sv))
+ return ERR_PTR(-ENOMEM);
+
+ sv->highest_lnum = sv->leb_count = 0;
+ si->max_sqnum = 0;
+ sv->vol_id = vol_id;
+ sv->root = RB_ROOT;
+ sv->used_ebs = ubi32_to_cpu(vid_hdr->used_ebs);
+ sv->data_pad = ubi32_to_cpu(vid_hdr->data_pad);
+ sv->compat = vid_hdr->compat;
+ sv->vol_type = vid_hdr->vol_type == UBI_VID_DYNAMIC ? UBI_DYNAMIC_VOLUME
+ : UBI_STATIC_VOLUME;
+ if (vol_id > si->highest_vol_id)
+ si->highest_vol_id = vol_id;
+
+ rb_link_node(&sv->rb, parent, p);
+ rb_insert_color(&sv->rb, &si->volumes);
+ si->vols_found += 1;
+ dbg_bld("added volume %d", vol_id);
+ return sv;
+}
+
+/**
+ * compare_lebs - find out which logical eraseblock is newer.
+ * @ubi: UBI device description object
+ * @seb: first logical eraseblock to compare
+ * @pnum: physical eraseblock number of the second logical eraseblock to
+ * compare
+ * @vid_hdr: volume identifier header of the second logical eraseblock
+ *
+ * This function compares 2 copies of a LEB and informs which one is newer. In
+ * case of success this function returns a positive value, in case of failure, a
+ * negative error code is returned. The success return codes use the following
+ * bits:
+ * o bit 0 is cleared: the first PEB (described by @seb) is newer then the
+ * second PEB (described by @pnum and @vid_hdr);
+ * o bit 0 is set: the second PEB is newer;
+ * o bit 1 is cleared: no bit-flips were detected in the newer LEB;
+ * o bit 1 is set: bit-flips were detected in the newer LEB;
+ * o bit 2 is cleared: the older LEB is not corrupted;
+ * o bit 2 is set: the older LEB is corrupted.
+ */
+static int compare_lebs(const struct ubi_device *ubi,
+ const struct ubi_scan_leb *seb, int pnum,
+ const struct ubi_vid_hdr *vid_hdr)
+{
+ void *buf;
+ int len, err, second_is_newer, bitflips = 0, corrupted = 0;
+ uint32_t data_crc, crc;
+ struct ubi_vid_hdr *vidh = NULL;
+ unsigned long long sqnum2 = ubi64_to_cpu(vid_hdr->sqnum);
+
+ if (seb->sqnum == 0 && sqnum2 == 0) {
+ long long abs, v1 = seb->leb_ver, v2 = ubi32_to_cpu(vid_hdr->leb_ver);
+
+ /*
+ * UBI constantly increases the logical eraseblock version
+ * number and it can overflow. Thus, we have to bear in mind
+ * that versions that are close to %0xFFFFFFFF are less then
+ * versions that are close to %0.
+ *
+ * The UBI WL unit guarantees that the number of pending tasks
+ * is not greater then %0x7FFFFFFF. So, if the difference
+ * between any two versions is greater or equivalent to
+ * %0x7FFFFFFF, there was an overflow and the logical
+ * eraseblock with lower version is actually newer then the one
+ * with higher version.
+ *
+ * FIXME: but this is anyway obsolete and will be removed at
+ * some point.
+ */
+
+ dbg_bld("using old crappy leb_ver stuff");
+
+ abs = v1 - v2;
+ if (abs < 0)
+ abs = -abs;
+
+ if (likely(abs < 0x7FFFFFFF))
+ /* Non-overflow situation */
+ second_is_newer = (v2 > v1);
+ else
+ second_is_newer = (v2 < v1);
+ } else
+ /* Obviously the LEB with lower sequence counter is older */
+ second_is_newer = sqnum2 > seb->sqnum;
+
+ /*
+ * Now we know which copy is newer. If the copy flag of the PEB with
+ * newer version is not set, then we just return, otherwise we have to
+ * check data CRC. For the second PEB we already have the VID header,
+ * for the first one - we'll need to re-read it from flash.
+ *
+ * FIXME: this may be optimized so that we wouldn't read twice.
+ */
+
+ if (second_is_newer) {
+ if (!vid_hdr->copy_flag) {
+ /* It is not a copy, so it is newer */
+ dbg_bld("second PEB %d is newer, copy_flag is unset",
+ pnum);
+ return 1;
+ }
+ } else {
+ pnum = seb->pnum;
+
+ vidh = ubi_zalloc_vid_hdr(ubi);
+ if (!vidh)
+ return -ENOMEM;
+
+ err = ubi_io_read_vid_hdr(ubi, pnum, vidh, 0);
+ if (unlikely(err)) {
+ if (err == UBI_IO_BITFLIPS)
+ bitflips = 1;
+ else {
+ dbg_err("VID of PEB %d header is bad, but it "
+ "was OK earlier", pnum);
+ if (err > 0)
+ err = -EIO;
+
+ goto out_free_vidh;
+ }
+ }
+
+ if (!vidh->copy_flag) {
+ /* It is not a copy, so it is newer */
+ dbg_bld("first PEB %d is newer, copy_flag is unset",
+ pnum);
+ err = bitflips << 1;
+ goto out_free_vidh;
+ }
+
+ vid_hdr = vidh;
+ }
+
+ /* Read the data of the copy and check the CRC */
+
+ len = ubi32_to_cpu(vid_hdr->data_size);
+ buf = kmalloc(len, GFP_KERNEL);
+ if (unlikely(!buf)) {
+ err = -ENOMEM;
+ goto out_free_vidh;
+ }
+
+ err = ubi_io_read_data(ubi, buf, pnum, 0, len);
+ if (unlikely(err && err != UBI_IO_BITFLIPS))
+ goto out_free_buf;
+
+ data_crc = ubi32_to_cpu(vid_hdr->data_crc);
+ crc = crc32(UBI_CRC32_INIT, buf, len);
+ if (unlikely(crc != data_crc)) {
+ dbg_bld("PEB %d CRC error: calculated %#08x, must be %#08x",
+ pnum, crc, data_crc);
+ corrupted = 1;
+ bitflips = 0;
+ second_is_newer = !second_is_newer;
+ } else {
+ dbg_bld("PEB %d CRC is OK", pnum);
+ bitflips = !!err;
+ }
+
+ kfree(buf);
+ ubi_free_vid_hdr(ubi, vidh);
+
+ if (second_is_newer)
+ dbg_bld("second PEB %d is newer, copy_flag is set", pnum);
+ else
+ dbg_bld("first PEB %d is newer, copy_flag is set", pnum);
+
+ return second_is_newer | (bitflips << 1) | (corrupted << 2);
+
+out_free_buf:
+ kfree(buf);
+out_free_vidh:
+ ubi_free_vid_hdr(ubi, vidh);
+ ubi_assert(err < 0);
+ return err;
+}
+
+/**
+ * ubi_scan_add_used - add information about a physical eraseblock to the
+ * scanning information.
+ * @ubi: UBI device description object
+ * @si: scanning information
+ * @pnum: the physical eraseblock number
+ * @ec: erase counter
+ * @vid_hdr: the volume identifier header
+ * @bitflips: if bit-flips were detected when this physical eraseblock was read
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+int ubi_scan_add_used(const struct ubi_device *ubi, struct ubi_scan_info *si,
+ int pnum, int ec, const struct ubi_vid_hdr *vid_hdr,
+ int bitflips)
+{
+ int err, vol_id, lnum;
+ uint32_t leb_ver;
+ unsigned long long sqnum;
+ struct ubi_scan_volume *sv;
+ struct ubi_scan_leb *seb;
+ struct rb_node **p, *parent = NULL;
+
+ vol_id = ubi32_to_cpu(vid_hdr->vol_id);
+ lnum = ubi32_to_cpu(vid_hdr->lnum);
+ sqnum = ubi64_to_cpu(vid_hdr->sqnum);
+ leb_ver = ubi32_to_cpu(vid_hdr->leb_ver);
+
+ dbg_bld("PEB %d, LEB %d:%d, EC %d, sqnum %llu, ver %u, bitflips %d",
+ pnum, vol_id, lnum, ec, sqnum, leb_ver, bitflips);
+
+ sv = add_volume(si, vol_id, pnum, vid_hdr);
+ if (unlikely(IS_ERR(sv)) < 0)
+ return PTR_ERR(sv);
+
+ /*
+ * Walk the RB-tree of logical eraseblocks of volume @vol_id to look
+ * if this is the first instance of this logical eraseblock or not.
+ */
+ p = &sv->root.rb_node;
+ while (*p) {
+ int cmp_res;
+
+ parent = *p;
+ seb = rb_entry(parent, struct ubi_scan_leb, u.rb);
+ if (lnum != seb->lnum) {
+ if (lnum < seb->lnum)
+ p = &(*p)->rb_left;
+ else
+ p = &(*p)->rb_right;
+ continue;
+ }
+
+ /*
+ * There is already a physical eraseblock describing the same
+ * logical eraseblock present.
+ */
+
+ dbg_bld("this LEB already exists: PEB %d, sqnum %llu, "
+ "LEB ver %u, EC %d", seb->pnum, seb->sqnum,
+ seb->leb_ver, seb->ec);
+
+ /*
+ * Make sure that the logical eraseblocks have different
+ * versions. Otherwise the image is bad.
+ */
+ if (unlikely(seb->leb_ver == leb_ver && leb_ver != 0)) {
+ ubi_err("two LEBs with same version %u", leb_ver);
+ ubi_dbg_dump_seb(seb, 0);
+ ubi_dbg_dump_vid_hdr(vid_hdr);
+ return -EINVAL;
+ }
+
+ /*
+ * Make sure that the logical eraseblocks have different
+ * sequence numbers. Otherwise the image is bad.
+ *
+ * FIXME: remove 'sqnum != 0' check when leb_ver is removed.
+ */
+ if (unlikely(seb->sqnum == sqnum && sqnum != 0)) {
+ ubi_err("two LEBs with same sequence number %llu",
+ sqnum);
+ ubi_dbg_dump_seb(seb, 0);
+ ubi_dbg_dump_vid_hdr(vid_hdr);
+ return -EINVAL;
+ }
+
+ /*
+ * Now we have to drop the older one and preserve the newer
+ * one.
+ */
+ cmp_res = compare_lebs(ubi, seb, pnum, vid_hdr);
+ if (unlikely(cmp_res < 0))
+ return cmp_res;
+
+ if (cmp_res & 1) {
+ /*
+ * This logical eraseblock is newer then the one
+ * found earlier.
+ */
+ err = validate_vid_hdr(vid_hdr, sv, pnum);
+ if (unlikely(err))
+ return err;
+
+ if (cmp_res & 4)
+ err = ubi_scan_add_to_list(si, seb->pnum,
+ seb->ec, &si->corr);
+ else
+ err = ubi_scan_add_to_list(si, seb->pnum,
+ seb->ec, &si->erase);
+ if (unlikely(err))
+ return err;
+
+ seb->ec = ec;
+ seb->pnum = pnum;
+ seb->scrub = ((cmp_res & 2) || bitflips);
+ seb->sqnum = sqnum;
+ seb->leb_ver = leb_ver;
+
+ if (sv->highest_lnum == lnum)
+ sv->last_data_size =
+ ubi32_to_cpu(vid_hdr->data_size);
+
+ return 0;
+ } else {
+ /*
+ * This logical eraseblock is older then the one found
+ * previously.
+ */
+ if (cmp_res & 4)
+ return ubi_scan_add_to_list(si, pnum, ec,
+ &si->corr);
+ else
+ return ubi_scan_add_to_list(si, pnum, ec,
+ &si->erase);
+ }
+ }
+
+ /*
+ * We've met this logical eraseblock for the first time, add it to the
+ * scanning information.
+ */
+
+ err = validate_vid_hdr(vid_hdr, sv, pnum);
+ if (unlikely(err))
+ return err;
+
+ seb = kmalloc(sizeof(struct ubi_scan_leb), GFP_KERNEL);
+ if (unlikely(!seb))
+ return -ENOMEM;
+
+ seb->ec = ec;
+ seb->pnum = pnum;
+ seb->lnum = lnum;
+ seb->sqnum = sqnum;
+ seb->scrub = bitflips;
+ seb->leb_ver = leb_ver;
+
+ if (sv->highest_lnum <= lnum) {
+ sv->highest_lnum = lnum;
+ sv->last_data_size = ubi32_to_cpu(vid_hdr->data_size);
+ }
+
+ if (si->max_sqnum < sqnum)
+ si->max_sqnum = sqnum;
+
+ sv->leb_count += 1;
+ rb_link_node(&seb->u.rb, parent, p);
+ rb_insert_color(&seb->u.rb, &sv->root);
+ return 0;
+}
+
+/**
+ * ubi_scan_find_sv - find information about a particular volume in the
+ * scanning information.
+ * @si: scanning information
+ * @vol_id: the requested volume ID
+ *
+ * This function returns a pointer to the volume description or %NULL if there
+ * are no data about this volume in the scanning information.
+ */
+struct ubi_scan_volume *ubi_scan_find_sv(const struct ubi_scan_info *si,
+ int vol_id)
+{
+ struct ubi_scan_volume *sv;
+ struct rb_node *p = si->volumes.rb_node;
+
+ while (p) {
+ sv = rb_entry(p, struct ubi_scan_volume, rb);
+
+ if (vol_id == sv->vol_id)
+ return sv;
+
+ if (vol_id > sv->vol_id)
+ p = p->rb_left;
+ else
+ p = p->rb_right;
+ }
+
+ return NULL;
+}
+
+/**
+ * ubi_scan_find_seb - find information about a particular logical
+ * eraseblock in the volume scanning information.
+ * @sv: a pointer to the volume scanning information
+ * @lnum: the requested logical eraseblock
+ *
+ * This function returns a pointer to the scanning logical eraseblock or %NULL
+ * if there are no data about it in the scanning volume information.
+ */
+struct ubi_scan_leb *ubi_scan_find_seb(const struct ubi_scan_volume *sv,
+ int lnum)
+{
+ struct ubi_scan_leb *seb;
+ struct rb_node *p = sv->root.rb_node;
+
+ while (p) {
+ seb = rb_entry(p, struct ubi_scan_leb, u.rb);
+
+ if (lnum == seb->lnum)
+ return seb;
+
+ if (lnum > seb->lnum)
+ p = p->rb_left;
+ else
+ p = p->rb_right;
+ }
+
+ return NULL;
+}
+
+/**
+ * ubi_scan_rm_volume - delete scanning information about a volume.
+ * @si: scanning information
+ * @sv: the volume scanning information to delete
+ */
+void ubi_scan_rm_volume(struct ubi_scan_info *si, struct ubi_scan_volume *sv)
+{
+ struct rb_node *rb;
+ struct ubi_scan_leb *seb;
+
+ dbg_bld("remove scanning information about volume %d", sv->vol_id);
+
+ while ((rb = rb_first(&sv->root))) {
+ seb = rb_entry(rb, struct ubi_scan_leb, u.rb);
+ rb_erase(&seb->u.rb, &sv->root);
+ list_add_tail(&seb->u.list, &si->erase);
+ }
+
+ rb_erase(&sv->rb, &si->volumes);
+ kfree(sv);
+ si->vols_found -= 1;
+}
+
+/**
+ * ubi_scan_erase_peb - erase a physical eraseblock.
+ * @ubi: UBI device description object
+ * @si: scanning information
+ * @pnum: physical eraseblock number to erase;
+ * @ec: erase counter value to write (%UBI_SCAN_UNKNOWN_EC if it is unknown)
+ *
+ * This function erases physical eraseblock 'pnum', and writes the erase
+ * counter header to it. This function should only be used on UBI device
+ * initialization stages, when the EBA unit had not been yet initialized. This
+ * function returns zero in case of success and a negative error code in case
+ * of failure.
+ */
+int ubi_scan_erase_peb(const struct ubi_device *ubi,
+ const struct ubi_scan_info *si, int pnum, int ec)
+{
+ int err;
+ struct ubi_ec_hdr *ec_hdr;
+
+ ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
+ if (!ec_hdr)
+ return -ENOMEM;
+
+ if (unlikely((long long)ec >= UBI_MAX_ERASECOUNTER)) {
+ /*
+ * Erase counter overflow. Upgrade UBI and use 64-bit
+ * erase counters internally.
+ */
+ ubi_err("erase counter overflow at PEB %d, EC %d", pnum, ec);
+ return -EINVAL;
+ }
+
+ ec_hdr->ec = cpu_to_ubi64(ec);
+
+ err = ubi_io_sync_erase(ubi, pnum, 0);
+ if (unlikely(err < 0))
+ goto out_free;
+
+ err = ubi_io_write_ec_hdr(ubi, pnum, ec_hdr);
+
+out_free:
+ kfree(ec_hdr);
+ return err;
+}
+
+/**
+ * ubi_scan_get_free_peb - get a free physical eraseblock.
+ * @ubi: UBI device description object
+ * @si: scanning information
+ *
+ * This function returns a free physical eraseblock. It is supposed to be
+ * called on the UBI initialization stages when the wear-leveling unit is not
+ * initialized yet. This function picks a physical eraseblocks from one of the
+ * lists, writes the EC header if it is needed, and removes it from the list.
+ *
+ * This function returns scanning physical eraseblock information in case of
+ * success and an error code in case of failure.
+ */
+struct ubi_scan_leb *ubi_scan_get_free_peb(const struct ubi_device *ubi,
+ struct ubi_scan_info *si)
+{
+ int err = 0, i;
+ struct ubi_scan_leb *seb;
+
+ if (!list_empty(&si->free)) {
+ seb = list_entry(si->free.next, struct ubi_scan_leb, u.list);
+ list_del(&seb->u.list);
+ dbg_bld("return free PEB %d, EC %d", seb->pnum, seb->ec);
+ return seb;
+ }
+
+ for (i = 0; i < 2; i++) {
+ struct list_head *head;
+ struct ubi_scan_leb *tmp_seb;
+
+ if (i == 0)
+ head = &si->erase;
+ else
+ head = &si->corr;
+
+ /*
+ * We try to erase the first physical eraseblock from the @head
+ * list and pick it if we succeed, or try to erase the
+ * next one if not. And so forth. We don't want to take care
+ * about bad eraseblocks here - they'll be handled later.
+ */
+ list_for_each_entry_safe(seb, tmp_seb, head, u.list) {
+ if (seb->ec == UBI_SCAN_UNKNOWN_EC)
+ seb->ec = si->mean_ec;
+
+ err = ubi_scan_erase_peb(ubi, si, seb->pnum, seb->ec+1);
+ if (unlikely(err))
+ continue;
+
+ seb->ec += 1;
+ list_del(&seb->u.list);
+ dbg_bld("return PEB %d, EC %d", seb->pnum, seb->ec);
+ return seb;
+ }
+ }
+
+ ubi_err("no eraseblocks found");
+ return ERR_PTR(-ENOSPC);
+}
+
+/**
+ * process_eb - read UBI headers, check them and add corresponding data
+ * to the scanning information.
+ * @ubi: UBI device description object
+ * @si: scanning information
+ * @pnum: the physical eraseblock number
+ *
+ * This function returns a zero if the physical eraseblock was succesfully
+ * handled and a negative error code in case of failure.
+ */
+static int process_eb(struct ubi_device *ubi, struct ubi_scan_info *si, int pnum)
+{
+ long long ec;
+ int err, bitflips = 0, vol_id, ec_corr = 0;
+
+ dbg_bld("scan PEB %d", pnum);
+
+ /* Skip bad physical eraseblocks */
+ err = ubi_io_is_bad(ubi, pnum);
+ if (unlikely(err < 0))
+ return err;
+ else if (err) {
+ /*
+ * FIXME: this is actually duty of the I/O unit to initialize
+ * this, but MTD does not provide enough information.
+ */
+ si->bad_peb_count += 1;
+ return 0;
+ }
+
+ err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
+ if (unlikely(err < 0))
+ return err;
+ else if (unlikely(err == UBI_IO_BITFLIPS))
+ bitflips = 1;
+ else if (err == UBI_IO_PEB_EMPTY)
+ return ubi_scan_add_to_list(si, pnum, UBI_SCAN_UNKNOWN_EC,
+ &si->erase);
+ else if (err == UBI_IO_BAD_EC_HDR) {
+ /*
+ * We have to also look at the VID header, possibly it is not
+ * corrupted. Set %bitflips flag in order to make this PEB be
+ * moved and EC be re-created.
+ */
+ ec_corr = 1;
+ ec = UBI_SCAN_UNKNOWN_EC;
+ bitflips = 1;
+ }
+
+ si->is_empty = 0;
+
+ if (!ec_corr) {
+ /* Make sure UBI version is OK */
+ if (unlikely(ech->version != UBI_VERSION)) {
+ ubi_err("this UBI version is %d, image version is %d",
+ UBI_VERSION, (int)ech->version);
+ return -EINVAL;
+ }
+
+ ec = ubi64_to_cpu(ech->ec);
+ if (unlikely(ec > UBI_MAX_ERASECOUNTER)) {
+ /*
+ * Erase counter overflow. The EC headers have 64 bits
+ * reserved, but we anyway make use of only 31 bit
+ * values, as this seems to be enough for any existing
+ * flash. Upgrade UBI and use 64-bit erase counters
+ * internally.
+ */
+ ubi_err("erase counter overflow, max is %d",
+ UBI_MAX_ERASECOUNTER);
+ ubi_dbg_dump_ec_hdr(ech);
+ return -EINVAL;
+ }
+ }
+
+ /* OK, we've done with the EC header, let's look at the VID header */
+
+ err = ubi_io_read_vid_hdr(ubi, pnum, vidh, 0);
+ if (unlikely(err < 0))
+ return err;
+ else if (unlikely(err == UBI_IO_BITFLIPS))
+ bitflips = 1;
+ else if (unlikely(err == UBI_IO_BAD_VID_HDR ||
+ (err == UBI_IO_PEB_FREE && ec_corr))) {
+ /* VID header is corrupted */
+ err = ubi_scan_add_to_list(si, pnum, ec, &si->corr);
+ if (err)
+ return err;
+ goto adjust_mean_ec;
+ } else if (err == UBI_IO_PEB_FREE) {
+ /* No VID header - the physical eraseblock is free */
+ err = ubi_scan_add_to_list(si, pnum, ec, &si->free);
+ if (unlikely(err))
+ return err;
+ goto adjust_mean_ec;
+ }
+
+ vol_id = ubi32_to_cpu(vidh->vol_id);
+ if (vol_id > UBI_MAX_VOLUMES && vol_id != UBI_LAYOUT_VOL_ID) {
+ int lnum = ubi32_to_cpu(vidh->lnum);
+
+ /* Unsupported internal volume */
+ switch (vidh->compat) {
+ case UBI_COMPAT_DELETE:
+ ubi_msg("\"delete\" compatible internal volume %d:%d"
+ " found, remove it", vol_id, lnum);
+ err = ubi_scan_add_to_list(si, pnum, ec, &si->corr);
+ if (unlikely(err))
+ return err;
+ break;
+
+ case UBI_COMPAT_RO:
+ ubi_msg("read-only compatible internal volume %d:%d"
+ " found, switch to read-only mode",
+ vol_id, lnum);
+ ubi->ro_mode = 1;
+ break;
+
+ case UBI_COMPAT_PRESERVE:
+ ubi_msg("\"preserve\" compatible internal volume %d:%d"
+ " found", vol_id, lnum);
+ err = ubi_scan_add_to_list(si, pnum, ec, &si->alien);
+ if (unlikely(err))
+ return err;
+ si->alien_peb_count += 1;
+ return 0;
+
+ case UBI_COMPAT_REJECT:
+ ubi_err("incompatible internal volume %d:%d found",
+ vol_id, lnum);
+ return -EINVAL;
+ }
+ }
+
+ /* Both UBI headers seem to be fine */
+ err = ubi_scan_add_used(ubi, si, pnum, ec, vidh, bitflips);
+ if (unlikely(err))
+ return err;
+
+adjust_mean_ec:
+ if (!ec_corr) {
+ if (si->ec_sum + ec < ec) {
+ commit_to_mean_value(si);
+ si->ec_sum = 0;
+ si->ec_count = 0;
+ } else {
+ si->ec_sum += ec;
+ si->ec_count += 1;
+ }
+
+ if (ec > si->max_ec)
+ si->max_ec = ec;
+ if (ec < si->min_ec)
+ si->min_ec = ec;
+ }
+
+ return 0;
+}
+
+/**
+ * ubi_scan - scan an MTD device.
+ * @ubi: UBI device description object
+ *
+ * This function does full scanning of an MTD device and returns complete
+ * information about it. In case of failure, an error code is returned.
+ */
+struct ubi_scan_info *ubi_scan(struct ubi_device *ubi)
+{
+ int err, pnum;
+ struct rb_node *rb1, *rb2;
+ struct ubi_scan_volume *sv;
+ struct ubi_scan_leb *seb;
+ struct ubi_scan_info *si;
+
+ si = kzalloc(sizeof(struct ubi_scan_info), GFP_KERNEL);
+ if (!si)
+ return ERR_PTR(-ENOMEM);
+
+ INIT_LIST_HEAD(&si->corr);
+ INIT_LIST_HEAD(&si->free);
+ INIT_LIST_HEAD(&si->erase);
+ INIT_LIST_HEAD(&si->alien);
+ si->volumes = RB_ROOT;
+ si->is_empty = 1;
+
+ err = -ENOMEM;
+ ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
+ if (!ech)
+ goto out_si;
+
+ vidh = ubi_zalloc_vid_hdr(ubi);
+ if (!vidh)
+ goto out_ech;
+
+ for (pnum = 0; pnum < ubi->peb_count; pnum++) {
+ cond_resched();
+
+ dbg_msg("process PEB %d", pnum);
+ err = process_eb(ubi, si, pnum);
+ if (unlikely(err < 0))
+ goto out_vidh;
+ }
+
+ dbg_msg("scanning is finished");
+
+ /* Finish mean erase counter calculations */
+ if (si->ec_count)
+ commit_to_mean_value(si);
+
+ if (si->is_empty)
+ ubi_msg("empty MTD device detected");
+
+ /*
+ * In case of unknown erase counter we use the mean erase counter
+ * value.
+ */
+ ubi_rb_for_each_entry(rb1, sv, &si->volumes, rb) {
+ ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb)
+ if (seb->ec == UBI_SCAN_UNKNOWN_EC)
+ seb->ec = si->mean_ec;
+ }
+
+ list_for_each_entry(seb, &si->free, u.list) {
+ if (seb->ec == UBI_SCAN_UNKNOWN_EC)
+ seb->ec = si->mean_ec;
+ }
+
+ list_for_each_entry(seb, &si->corr, u.list)
+ if (seb->ec == UBI_SCAN_UNKNOWN_EC)
+ seb->ec = si->mean_ec;
+
+ list_for_each_entry(seb, &si->erase, u.list)
+ if (seb->ec == UBI_SCAN_UNKNOWN_EC)
+ seb->ec = si->mean_ec;
+
+ err = paranoid_check_si(ubi, si);
+ if (err) {
+ if (err > 0)
+ err = -EINVAL;
+ goto out_vidh;
+ }
+
+ ubi_free_vid_hdr(ubi, vidh);
+ kfree(ech);
+
+ return si;
+
+out_vidh:
+ ubi_free_vid_hdr(ubi, vidh);
+out_ech:
+ kfree(ech);
+out_si:
+ ubi_scan_destroy_si(si);
+ return ERR_PTR(err);
+}
+
+/**
+ * destroy_sv - free the scanning volume information
+ * @sv: scanning volume information
+ *
+ * This function destroys the volume RB-tree (@sv->root) and the scanning
+ * volume information.
+ */
+static void destroy_sv(struct ubi_scan_volume *sv)
+{
+ struct ubi_scan_leb *seb;
+ struct rb_node *this = sv->root.rb_node;
+
+ while (this) {
+ if (this->rb_left)
+ this = this->rb_left;
+ else if (this->rb_right)
+ this = this->rb_right;
+ else {
+ seb = rb_entry(this, struct ubi_scan_leb, u.rb);
+ this = rb_parent(this);
+ if (this) {
+ if (this->rb_left == &seb->u.rb)
+ this->rb_left = NULL;
+ else
+ this->rb_right = NULL;
+ }
+
+ kfree(seb);
+ }
+ }
+ kfree(sv);
+}
+
+/**
+ * ubi_scan_destroy_si - destroy scanning information.
+ * @si: scanning information
+ */
+void ubi_scan_destroy_si(struct ubi_scan_info *si)
+{
+ struct ubi_scan_leb *seb, *seb_tmp;
+ struct ubi_scan_volume *sv;
+ struct rb_node *rb;
+
+ list_for_each_entry_safe(seb, seb_tmp, &si->alien, u.list) {
+ list_del(&seb->u.list);
+ kfree(seb);
+ }
+ list_for_each_entry_safe(seb, seb_tmp, &si->erase, u.list) {
+ list_del(&seb->u.list);
+ kfree(seb);
+ }
+ list_for_each_entry_safe(seb, seb_tmp, &si->corr, u.list) {
+ list_del(&seb->u.list);
+ kfree(seb);
+ }
+ list_for_each_entry_safe(seb, seb_tmp, &si->free, u.list) {
+ list_del(&seb->u.list);
+ kfree(seb);
+ }
+
+ /* Destroy the volume RB-tree */
+ rb = si->volumes.rb_node;
+ while (rb) {
+ if (rb->rb_left)
+ rb = rb->rb_left;
+ else if (rb->rb_right)
+ rb = rb->rb_right;
+ else {
+ sv = rb_entry(rb, struct ubi_scan_volume, rb);
+
+ rb = rb_parent(rb);
+ if (rb) {
+ if (rb->rb_left == &sv->rb)
+ rb->rb_left = NULL;
+ else
+ rb->rb_right = NULL;
+ }
+
+ destroy_sv(sv);
+ }
+ }
+
+ kfree(si);
+}
+
+#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
+
+/**
+ * paranoid_check_si - check if the scanning information is correct and
+ * consistent.
+ * @ubi: UBI device description object
+ * @si: scanning information
+ *
+ * This function returns zero if the scanning information is all right, %1 if
+ * not and a negative error code if an error occurred.
+ */
+static int paranoid_check_si(const struct ubi_device *ubi,
+ struct ubi_scan_info *si)
+{
+ int pnum, err, vols_found = 0;
+ struct rb_node *rb1, *rb2;
+ struct ubi_scan_volume *sv;
+ struct ubi_scan_leb *seb, *last_seb;
+ uint8_t *buf;
+
+ /*
+ * At first, check that scanning information is ok.
+ */
+ ubi_rb_for_each_entry(rb1, sv, &si->volumes, rb) {
+ int leb_count = 0;
+
+ cond_resched();
+
+ vols_found += 1;
+
+ if (unlikely(si->is_empty)) {
+ ubi_err("bad is_empty flag");
+ goto bad_sv;
+ }
+
+ if (unlikely(sv->vol_id < 0 || sv->highest_lnum < 0 ||
+ sv->leb_count < 0 || sv->vol_type < 0 ||
+ sv->used_ebs < 0 || sv->data_pad < 0 ||
+ sv->last_data_size < 0)) {
+ ubi_err("negative values");
+ goto bad_sv;
+ }
+
+ if (unlikely(sv->vol_id >= UBI_MAX_VOLUMES &&
+ sv->vol_id < UBI_INTERNAL_VOL_START)) {
+ ubi_err("bad vol_id");
+ goto bad_sv;
+ }
+
+ if (unlikely(sv->vol_id > si->highest_vol_id)) {
+ ubi_err("highest_vol_id is %d, but vol_id %d is there",
+ si->highest_vol_id, sv->vol_id);
+ goto out;
+ }
+
+ if (unlikely(sv->vol_type != UBI_DYNAMIC_VOLUME &&
+ sv->vol_type != UBI_STATIC_VOLUME)) {
+ ubi_err("bad vol_type");
+ goto bad_sv;
+ }
+
+ if (unlikely(sv->data_pad > ubi->leb_size / 2)) {
+ ubi_err("bad data_pad");
+ goto bad_sv;
+ }
+
+ last_seb = NULL;
+ ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb) {
+ cond_resched();
+
+ last_seb = seb;
+ leb_count += 1;
+
+ if (unlikely(seb->pnum < 0 || seb->ec < 0)) {
+ ubi_err("negative values");
+ goto bad_seb;
+ }
+
+ if (unlikely(seb->ec < si->min_ec)) {
+ ubi_err("bad si->min_ec (%d), %d found",
+ si->min_ec, seb->ec);
+ goto bad_seb;
+ }
+
+ if (unlikely(seb->ec > si->max_ec)) {
+ ubi_err("bad si->max_ec (%d), %d found",
+ si->max_ec, seb->ec);
+ goto bad_seb;
+ }
+
+ if (unlikely(seb->pnum >= ubi->peb_count)) {
+ ubi_err("too high PEB number %d, total PEBs %d",
+ seb->pnum, ubi->peb_count);
+ goto bad_seb;
+ }
+
+ if (sv->vol_type == UBI_STATIC_VOLUME) {
+ if (unlikely(seb->lnum >= sv->used_ebs)) {
+ ubi_err("bad lnum or used_ebs");
+ goto bad_seb;
+ }
+ } else {
+ if (unlikely(sv->used_ebs != 0)) {
+ ubi_err("non-zero used_ebs");
+ goto bad_seb;
+ }
+ }
+
+ if (unlikely(seb->lnum > sv->highest_lnum)) {
+ ubi_err("incorrect highest_lnum or lnum");
+ goto bad_seb;
+ }
+ }
+
+ if (unlikely(sv->leb_count != leb_count)) {
+ ubi_err("bad leb_count, %d objects in the tree",
+ leb_count);
+ goto bad_sv;
+ }
+
+ if (!last_seb)
+ continue;
+
+ seb = last_seb;
+
+ if (unlikely(seb->lnum != sv->highest_lnum)) {
+ ubi_err("bad highest_lnum");
+ goto bad_seb;
+ }
+ }
+
+ if (vols_found != si->vols_found) {
+ ubi_err("bad si->vols_found %d, should be %d",
+ si->vols_found, vols_found);
+ goto out;
+ }
+
+ /* Check that scanning information is correct */
+ ubi_rb_for_each_entry(rb1, sv, &si->volumes, rb) {
+ last_seb = NULL;
+ ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb) {
+ int vol_type;
+
+ cond_resched();
+
+ last_seb = seb;
+
+ err = ubi_io_read_vid_hdr(ubi, seb->pnum, vidh, 1);
+ if (unlikely(err) && err != UBI_IO_BITFLIPS) {
+ ubi_err("VID header is not OK (%d)", err);
+ if (err > 0)
+ err = -EIO;
+ return err;
+ }
+
+ vol_type = vidh->vol_type == UBI_VID_DYNAMIC ?
+ UBI_DYNAMIC_VOLUME : UBI_STATIC_VOLUME;
+ if (unlikely(sv->vol_type != vol_type)) {
+ ubi_err("bad vol_type");
+ goto bad_vid_hdr;
+ }
+
+ if (unlikely(seb->sqnum != ubi64_to_cpu(vidh->sqnum))) {
+ ubi_err("bad sqnum %llu", seb->sqnum);
+ goto bad_vid_hdr;
+ }
+
+ if (unlikely(sv->vol_id !=
+ ubi32_to_cpu(vidh->vol_id))) {
+ ubi_err("bad vol_id %d", sv->vol_id);
+ goto bad_vid_hdr;
+ }
+
+ if (unlikely(sv->compat != vidh->compat)) {
+ ubi_err("bad compat %d", vidh->compat);
+ goto bad_vid_hdr;
+ }
+
+ if (unlikely(seb->lnum != ubi32_to_cpu(vidh->lnum))) {
+ ubi_err("bad lnum %d", seb->lnum);
+ goto bad_vid_hdr;
+ }
+
+ if (unlikely(sv->used_ebs !=
+ ubi32_to_cpu(vidh->used_ebs))) {
+ ubi_err("bad used_ebs %d", sv->used_ebs);
+ goto bad_vid_hdr;
+ }
+
+ if (unlikely(sv->data_pad !=
+ ubi32_to_cpu(vidh->data_pad))) {
+ ubi_err("bad data_pad %d", sv->data_pad);
+ goto bad_vid_hdr;
+ }
+
+ if (unlikely(seb->leb_ver !=
+ ubi32_to_cpu(vidh->leb_ver))) {
+ ubi_err("bad leb_ver %u", seb->leb_ver);
+ goto bad_vid_hdr;
+ }
+ }
+
+ if (!last_seb)
+ continue;
+
+ if (unlikely(sv->highest_lnum != ubi32_to_cpu(vidh->lnum))) {
+ ubi_err("bad highest_lnum %d", sv->highest_lnum);
+ goto bad_vid_hdr;
+ }
+
+ if (unlikely(sv->last_data_size !=
+ ubi32_to_cpu(vidh->data_size))) {
+ ubi_err("bad last_data_size %d", sv->last_data_size);
+ goto bad_vid_hdr;
+ }
+ }
+
+ /*
+ * Make sure that all the physical eraseblocks are in one of the lists
+ * or trees.
+ */
+ buf = kmalloc(ubi->peb_count, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ memset(buf, 1, ubi->peb_count);
+ for (pnum = 0; pnum < ubi->peb_count; pnum++) {
+ err = ubi_io_is_bad(ubi, pnum);
+ if (unlikely(err < 0))
+ return err;
+ else if (err)
+ buf[pnum] = 0;
+ }
+
+ ubi_rb_for_each_entry(rb1, sv, &si->volumes, rb)
+ ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb)
+ buf[seb->pnum] = 0;
+
+ list_for_each_entry(seb, &si->free, u.list)
+ buf[seb->pnum] = 0;
+
+ list_for_each_entry(seb, &si->corr, u.list)
+ buf[seb->pnum] = 0;
+
+ list_for_each_entry(seb, &si->erase, u.list)
+ buf[seb->pnum] = 0;
+
+ list_for_each_entry(seb, &si->alien, u.list)
+ buf[seb->pnum] = 0;
+
+ err = 0;
+ for (pnum = 0; pnum < ubi->peb_count; pnum++)
+ if (unlikely(buf[pnum])) {
+ ubi_err("PEB %d is not referred", pnum);
+ err = 1;
+ }
+
+ kfree(buf);
+ if (err)
+ goto out;
+ return 0;
+
+bad_seb:
+ ubi_err("bad scanning information about LEB %d", seb->lnum);
+ ubi_dbg_dump_seb(seb, 0);
+ ubi_dbg_dump_sv(sv);
+ goto out;
+
+bad_sv:
+ ubi_err("bad scanning information about volume %d", sv->vol_id);
+ ubi_dbg_dump_sv(sv);
+ goto out;
+
+bad_vid_hdr:
+ ubi_err("bad scanning information about volume %d", sv->vol_id);
+ ubi_dbg_dump_sv(sv);
+ ubi_dbg_dump_vid_hdr(vidh);
+
+out:
+ ubi_dbg_dump_stack();
+ return 1;
+}
+
+#endif /* CONFIG_MTD_UBI_DEBUG_PARANOID */
diff -auNrp tmp-from/drivers/mtd/ubi/scan.h tmp-to/drivers/mtd/ubi/scan.h
--- tmp-from/drivers/mtd/ubi/scan.h 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/scan.h 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,167 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+#ifndef __UBI_SCAN_H__
+#define __UBI_SCAN_H__
+
+/* The erase counter value for this physical eraseblock is unknown */
+#define UBI_SCAN_UNKNOWN_EC (-1)
+
+/**
+ * struct ubi_scan_leb - scanning information about a physical eraseblock.
+ * @ec: erase counter (%UBI_SCAN_UNKNOWN_EC if it is unknown)
+ * @pnum: physical eraseblock number
+ * @lnum: logical eraseblock number
+ * @scrub: if this physical eraseblock needs scrubbing
+ * @sqnum: sequence number
+ * @u: unions RB-tree or @list links
+ * @u.rb: link in the per-volume RB-tree of &struct ubi_scan_leb objects
+ * @u.list: link in one of the eraseblock lists
+ * @leb_ver: logical eraseblock version (obsolete)
+ *
+ * One object of this type is allocated for each physical eraseblock during
+ * scanning.
+ */
+struct ubi_scan_leb {
+ int ec;
+ int pnum;
+ int lnum;
+ int scrub;
+ unsigned long long sqnum;
+ union {
+ struct rb_node rb;
+ struct list_head list;
+ } u;
+ uint32_t leb_ver;
+};
+
+/**
+ * struct ubi_scan_volume - scanning information about a volume.
+ * @vol_id: volume ID
+ * @highest_lnum: highest logical eraseblock number in this volume
+ * @leb_count: number of logical eraseblocks in this volume
+ * @vol_type: volume type
+ * @used_ebs: number of used logical eraseblocks in this volume (only for
+ * static volumes)
+ * @last_data_size: amount of data in the last logical eraseblock of this
+ * volume (always equivalent to the usable logical eraseblock size in case of
+ * dynamic volumes)
+ * @data_pad: how many bytes at the end of logical eraseblocks of this volume
+ * are not used (due to volume alignment)
+ * @compat: compatibility flags of this volume
+ * @rb: link in the volume RB-tree
+ * @root: root of the RB-tree containing all the eraseblock belonging to this
+ * volume (&struct ubi_scan_leb objects)
+ *
+ * One object of this type is allocated for each volume during scanning.
+ */
+struct ubi_scan_volume {
+ int vol_id;
+ int highest_lnum;
+ int leb_count;
+ int vol_type;
+ int used_ebs;
+ int last_data_size;
+ int data_pad;
+ int compat;
+ struct rb_node rb;
+ struct rb_root root;
+};
+
+/**
+ * struct ubi_scan_info - UBI scanning information.
+ * @volumes: root of the volume RB-tree
+ * @corr: list of corrupted physical eraseblocks
+ * @free: list of free physical eraseblocks
+ * @erase: list of physical eraseblocks which have to be erased
+ * @alien: list of physical eraseblocks which should not be used by UBI (e.g.,
+ * @bad_peb_count: count of bad physical eraseblocks
+ * those belonging to "preserve"-compatible internal volumes)
+ * @vols_found: number of volumes found during scanning
+ * @highest_vol_id: highest volume ID
+ * @alien_peb_count: count of physical eraseblocks in the @alien list
+ * @is_empty: flag indicating whether the MTD device is empty or not
+ * @min_ec: lowest erase counter value
+ * @max_ec: highest erase counter value
+ * @max_sqnum: highest sequence number value
+ * @mean_ec: mean erase counter value
+ * @ec_sum: a temporary variable used when calculating @mean_ec
+ * @ec_count: a temporary variable used when calculating @mean_ec
+ *
+ * This data structure contains the result of scanning and may be used by other
+ * UBI units to build final UBI data structures, further error-recovery and so
+ * on.
+ */
+struct ubi_scan_info {
+ struct rb_root volumes;
+ struct list_head corr;
+ struct list_head free;
+ struct list_head erase;
+ struct list_head alien;
+ int bad_peb_count;
+ int vols_found;
+ int highest_vol_id;
+ int alien_peb_count;
+ int is_empty;
+ int min_ec;
+ int max_ec;
+ unsigned long long max_sqnum;
+ int mean_ec;
+ int ec_sum;
+ int ec_count;
+};
+
+struct ubi_device;
+struct ubi_vid_hdr;
+
+/*
+ * ubi_scan_move_to_list - move a physical eraseblock from the volume tree to a
+ * list.
+ *
+ * @sv: volume scanning information
+ * @seb: scanning eraseblock infprmation
+ * @list: the list to move to
+ */
+static inline void ubi_scan_move_to_list(struct ubi_scan_volume *sv,
+ struct ubi_scan_leb *seb,
+ struct list_head *list)
+{
+ rb_erase(&seb->u.rb, &sv->root);
+ list_add_tail(&seb->u.list, list);
+}
+
+int ubi_scan_add_to_list(struct ubi_scan_info *si, int pnum, int ec,
+ struct list_head *list);
+int ubi_scan_add_used(const struct ubi_device *ubi, struct ubi_scan_info *si,
+ int pnum, int ec, const struct ubi_vid_hdr *vid_hdr,
+ int bitflips);
+struct ubi_scan_volume *ubi_scan_find_sv(const struct ubi_scan_info *si,
+ int vol_id);
+struct ubi_scan_leb *ubi_scan_find_seb(const struct ubi_scan_volume *sv,
+ int lnum);
+void ubi_scan_rm_volume(struct ubi_scan_info *si, struct ubi_scan_volume *sv);
+struct ubi_scan_leb *ubi_scan_get_free_peb(const struct ubi_device *ubi,
+ struct ubi_scan_info *si);
+int ubi_scan_erase_peb(const struct ubi_device *ubi,
+ const struct ubi_scan_info *si, int pnum, int ec);
+struct ubi_scan_info *ubi_scan(struct ubi_device *ubi);
+void ubi_scan_destroy_si(struct ubi_scan_info *si);
+
+#endif /* !__UBI_SCAN_H__ */
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 07/20 take 4] UBI: I/O unit
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (5 preceding siblings ...)
2007-03-23 16:43 ` [PATCH 06/20 take 4] UBI: scanning unit Artem Bityutskiy
@ 2007-03-23 16:43 ` Artem Bityutskiy
2007-03-23 16:43 ` [PATCH 08/20 take 4] UBI: volume table unit Artem Bityutskiy
` (12 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:43 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 39779 bytes --]
diff -auNrp tmp-from/drivers/mtd/ubi/io.c tmp-to/drivers/mtd/ubi/io.c
--- tmp-from/drivers/mtd/ubi/io.c 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/io.c 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,1263 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ * Copyright (c) Nokia Corporation, 2006, 2007
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * UBI input/output unit.
+ *
+ * This unit provides a uniform way to work with all kinds of the underlying
+ * MTD devices. It also implements handy functions for reading and writing UBI
+ * headers.
+ *
+ * We are trying to have a paranoid mindset and not to trust to what we read
+ * from the flash media in order to be more secure and robust. So this unit
+ * validates every single header it reads from the flash media.
+ *
+ * Some words about how the eraseblock headers are stored.
+ *
+ * The erase counter header is always stored at offset zero. By default, the
+ * VID header is stored after the EC header at the closest aligned offset
+ * (i.e. aligned to the minimum I/O unit size). Data starts next to the VID
+ * header at the closest aligned offset. But this default layout may be
+ * changed. For example, for different reasons (e.g., optimization) UBI may be
+ * asked to put the VID header at further offset, and even at an unaligned
+ * offset. Of course, if the offset of the VID header is unaligned, UBI adds
+ * proper padding in front of it. Data offset may also be changed but it has to
+ * be aligned.
+ *
+ * About minimal I/O units. In general, UBI assumes flash device model where
+ * there is only one minimal I/O unit size. E.g., in case of NOR flash it is 1,
+ * in case of NAND flash it is a NAND page, etc. This is reported by MTD in the
+ * @ubi->mtd->writesize field. But as an exception, UBI admits of using another
+ * (smaller) minimal I/O unit size for EC and VID headers to make it possible
+ * to do different optimizations.
+ *
+ * This is extremely useful in case of NAND flashes which admit of several
+ * write operations to one NAND page. In this case UBI can fit EC and VID
+ * headers at one NAND page. Thus, UBI may use "sub-page" size as the minimal
+ * I/O unit for the headers (the @ubi->hdrs_min_io_size field). But it still
+ * reports NAND page size (@ubi->min_io_size) as a minimal I/O unit for the UBI
+ * users.
+ *
+ * Example: some Samsung NANDs with 2KiB pages allow 4x 512-byte writes, so
+ * although the minimal I/O unit is 2K, UBI uses 512 bytes for EC and VID
+ * headers.
+ *
+ * Q: why not just to treat sub-page as a minimal I/O unit of this flash
+ * device, e.g., make @ubi->min_io_size = 512 in the example above?
+ *
+ * A: because when writing a sub-page, MTD still writes a full 2K page but the
+ * bytes which are no relevant to the sub-page are 0xFF. So, basically, writing
+ * 4x512 sub-pages is 4 times slower then writing one 2KiB NAND page. Thus, we
+ * prefer to use sub-pages only for EV and VID headers.
+ *
+ * As it was noted above, the VID header may start at a non-aligned offset.
+ * For example, in case of a 2KiB page NAND flash with a 512 bytes sub-page,
+ * the VID header may reside at offset 1984 which is the last 64 bytes of the
+ * last sub-page (EC header is always at offset zero). This causes some
+ * difficulties when reading and writing VID headers.
+ *
+ * Suppose we have a 64-byte buffer and we read a VID header at it. We change
+ * the data and want to write this VID header out. As we can only write in
+ * 512-byte chunks, we have to allocate one more buffer and copy our VID header
+ * to offset 448 of this buffer.
+ *
+ * The I/O unit does the following trick in order to avoid this extra copy.
+ * It always allocates a @ubi->vid_hdr_alsize bytes buffer for the VID header
+ * and returns a pointer to offset @ubi->vid_hdr_shift of this buffer. When the
+ * VID header is being written out, it shifts the VID header pointer back and
+ * writes the whole sub-page.
+ */
+
+#include <linux/crc32.h>
+#include <linux/err.h>
+#include "ubi.h"
+
+#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
+static int paranoid_check_not_bad(const struct ubi_device *ubi, int pnum);
+static int paranoid_check_peb_ec_hdr(const struct ubi_device *ubi, int pnum);
+static int paranoid_check_ec_hdr(const struct ubi_device *ubi, int pnum,
+ const struct ubi_ec_hdr *ec_hdr);
+static int paranoid_check_peb_vid_hdr(const struct ubi_device *ubi, int pnum);
+static int paranoid_check_vid_hdr(const struct ubi_device *ubi, int pnum,
+ const struct ubi_vid_hdr *vid_hdr);
+static int paranoid_check_all_ff(const struct ubi_device *ubi, int pnum,
+ int offset, int len);
+#else
+#define paranoid_check_not_bad(ubi, pnum) 0
+#define paranoid_check_peb_ec_hdr(ubi, pnum) 0
+#define paranoid_check_ec_hdr(ubi, pnum, ec_hdr) 0
+#define paranoid_check_peb_vid_hdr(ubi, pnum) 0
+#define paranoid_check_vid_hdr(ubi, pnum, vid_hdr) 0
+#define paranoid_check_all_ff(ubi, pnum, offset, len) 0
+#endif
+
+/**
+ * ubi_io_read - read data from a physical eraseblock.
+ * @ubi: UBI device description object
+ * @buf: buffer where to store the read data
+ * @pnum: physical eraseblock number to read from
+ * @offset: offset within the physical eraseblock from where to read
+ * @len: how many bytes to read
+ *
+ * This function reads data from offset @offset of physical eraseblock @pnum
+ * and stores the read data in the @buf buffer. The following return codes are
+ * possible:
+ *
+ * o %0 if all the requested data were successfully read;
+ * o %UBI_IO_BITFLIPS if all the requested data were successfully read, but
+ * correctable bit-flips were detected; this is harmless but may indicate
+ * that this eraseblock may become bad soon (but do not have to);
+ * o %-EBADMSG if the MTD subsystem reported about data data integrity
+ * problems, for example it can me an ECC error in case of NAND; this most
+ * probably means that the data is corrupted;
+ * o %-EIO if some I/O error occurred;
+ * o other negative error codes in case of other errors.
+ */
+int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset,
+ int len)
+{
+ int err, retries = 0;
+ size_t read;
+ loff_t addr;
+
+ dbg_io("read %d bytes from PEB %d:%d", len, pnum, offset);
+
+ ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
+ ubi_assert(offset >= 0 && offset + len <= ubi->peb_size);
+ ubi_assert(len > 0);
+
+ err = paranoid_check_not_bad(ubi, pnum);
+ if (unlikely(err))
+ return err > 0 ? -EINVAL : err;
+
+ addr = (loff_t)pnum * ubi->peb_size + offset;
+retry:
+ err = ubi->mtd->read(ubi->mtd, addr, len, &read, buf);
+ if (unlikely(err)) {
+ if (err == -EUCLEAN) {
+ /*
+ * -EUCLEAN is reported if there was a bit-flip which
+ * was corrected, so this is harmless.
+ */
+ ubi_msg("fixable bit-flip detected at PEB %d", pnum);
+ ubi_assert(len == read);
+ return UBI_IO_BITFLIPS;
+ }
+
+ if (read != len && retries++ < UBI_IO_RETRIES) {
+ dbg_io("error %d while reading %d bytes from PEB %d:%d, "
+ "read only %zd bytes, retry",
+ err, len, pnum, offset, read);
+ yield();
+ goto retry;
+ }
+
+ ubi_err("error %d while reading %d bytes from PEB %d:%d, "
+ "read %zd bytes", err, len, pnum, offset, read);
+ ubi_dbg_dump_stack();
+ } else {
+ ubi_assert(len == read);
+
+ if (ubi_dbg_is_bitflip()) {
+ ubi_msg("bit-flip (emulated)");
+ err = UBI_IO_BITFLIPS;
+ }
+ }
+
+ return err;
+}
+
+/**
+ * ubi_io_write - write data to a physical eraseblock.
+ * @ubi: UBI device description object
+ * @buf: buffer with the data to write
+ * @pnum: physical eraseblock number to write to
+ * @offset: offset within the physical eraseblock where to write
+ * @len: how many bytes to write
+ *
+ * This function writes @len bytes of data from buffer @buf to offset @offset
+ * of physical eraseblock @pnum. If all the data were successfully written,
+ * zero is returned. If an error occurred, this function returns a negative
+ * error code. If %-EIO is returned, the physical eraseblock most probably went
+ * bad.
+ *
+ * Note, in case of an error, it is possible that something was still written
+ * to the flash media, but may be some garbage.
+ */
+int ubi_io_write(const struct ubi_device *ubi, const void *buf, int pnum,
+ int offset, int len)
+{
+ int err;
+ size_t written;
+ loff_t addr;
+
+ dbg_io("write %d bytes to PEB %d:%d", len, pnum, offset);
+
+ ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
+ ubi_assert(offset >= 0 && offset + len <= ubi->peb_size);
+ ubi_assert(offset % ubi->hdrs_min_io_size == 0);
+ ubi_assert(len > 0 && len % ubi->hdrs_min_io_size == 0);
+
+ if (unlikely(ubi->ro_mode)) {
+ ubi_err("read-only mode");
+ return -EROFS;
+ }
+
+ /* The below has to be compiled out if paranoid checks are disabled */
+
+ err = paranoid_check_not_bad(ubi, pnum);
+ if (unlikely(err))
+ return err > 0 ? -EINVAL : err;
+
+ /* The area we are writing to has to contain all 0xFF bytes */
+ err = paranoid_check_all_ff(ubi, pnum, offset, len);
+ if (unlikely(err))
+ return err > 0 ? -EINVAL : err;
+
+ if (offset >= ubi->leb_start) {
+ /*
+ * We write to the data area of the physical eraseblock. Make
+ * sure it has valid EC and VID headers.
+ */
+ err = paranoid_check_peb_ec_hdr(ubi, pnum);
+ if (unlikely(err))
+ return err > 0 ? -EINVAL : err;
+ err = paranoid_check_peb_vid_hdr(ubi, pnum);
+ if (unlikely(err))
+ return err > 0 ? -EINVAL : err;
+ }
+
+ if (ubi_dbg_is_write_failure()) {
+ ubi_err("cannot write %d bytes to PEB %d:%d "
+ "(emulated)", len, pnum, offset);
+ ubi_dbg_dump_stack();
+ return -EIO;
+ }
+
+ addr = (loff_t)pnum * ubi->peb_size + offset;
+ err = ubi->mtd->write(ubi->mtd, addr, len, &written, buf);
+ if (unlikely(err)) {
+ ubi_err("error %d while writing %d bytes to PEB %d:%d, written"
+ " %zd bytes", err, len, pnum, offset, written);
+ ubi_dbg_dump_stack();
+ } else
+ ubi_assert(written == len);
+
+ return err;
+}
+
+/**
+ * erase_callback - MTD erasure call-back.
+ * @ei: MTD erase information object.
+ *
+ * Note, even though MTD erase interface is asynchronous, all the current
+ * implementations are synchronous anyway.
+ */
+static void erase_callback(struct erase_info *ei)
+{
+ wake_up_interruptible((wait_queue_head_t *)ei->priv);
+}
+
+/**
+ * do_sync_erase - synchronously erase a physical eraseblock.
+ * @ubi: UBI device description object
+ * @pnum: the physical eraseblock number to erase
+ *
+ * This function synchronously erases physical eraseblock @pnum and returns
+ * zero in case of success and a negative error code in case of failure. If
+ * %-EIO is returned, the physical eraseblock most probably went bad.
+ */
+static int do_sync_erase(const struct ubi_device *ubi, int pnum)
+{
+ int err, retries = 0;
+ struct erase_info ei;
+ wait_queue_head_t wq;
+
+ dbg_io("erase PEB %d", pnum);
+
+retry:
+ init_waitqueue_head(&wq);
+ memset(&ei, 0, sizeof(struct erase_info));
+
+ ei.mtd = ubi->mtd;
+ ei.addr = pnum * ubi->peb_size;
+ ei.len = ubi->peb_size;
+ ei.callback = erase_callback;
+ ei.priv = (unsigned long)&wq;
+
+ err = ubi->mtd->erase(ubi->mtd, &ei);
+ if (unlikely(err)) {
+ if (retries++ < UBI_IO_RETRIES) {
+ dbg_io("error %d while erasing PEB %d, retry",
+ err, pnum);
+ yield();
+ goto retry;
+ }
+ ubi_err("cannot erase PEB %d, error %d", pnum, err);
+ ubi_dbg_dump_stack();
+ return err;
+ }
+
+ err = wait_event_interruptible(wq, ei.state == MTD_ERASE_DONE ||
+ ei.state == MTD_ERASE_FAILED);
+ if (unlikely(err)) {
+ ubi_err("interrupted PEB %d erasure", pnum);
+ return -EINTR;
+ }
+
+ if (unlikely(ei.state == MTD_ERASE_FAILED)) {
+ if (retries++ < UBI_IO_RETRIES) {
+ dbg_io("error while erasing PEB %d, retry", pnum);
+ yield();
+ goto retry;
+ }
+ ubi_err("cannot erase PEB %d", pnum);
+ ubi_dbg_dump_stack();
+ return -EIO;
+ }
+
+ err = paranoid_check_all_ff(ubi, pnum, 0, ubi->peb_size);
+ if (unlikely(err))
+ return err > 0 ? -EINVAL : err;
+
+ if (ubi_dbg_is_erase_failure() && !err) {
+ ubi_err("cannot erase PEB %d (emulated)", pnum);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+/**
+ * check_pattern - check if buffer contains only a certain byte pattern.
+ * @buf: buffer to check
+ * @patt: the pattern to check
+ * @size: buffer size in bytes
+ *
+ * This function returns %1 in there are only @patt bytes in @buf, and %0 if
+ * something else was also found.
+ */
+static int check_pattern(const void *buf, uint8_t patt, int size)
+{
+ int i;
+
+ for (i = 0; i < size; i++)
+ if (((const uint8_t *)buf)[i] != patt)
+ return 0;
+ return 1;
+}
+
+/* Patterns to write to a physical eraseblock when torturing it */
+static uint8_t patterns[] = {0xa5, 0x5a, 0x0};
+
+/**
+ * torture_peb - test a supposedly bad physical eraseblock.
+ * @ubi: UBI device description object
+ * @pnum: the physical eraseblock number to test
+ *
+ * This function returns %-EIO if the physical eraseblock did not pass the
+ * test, a positive number of erase operations done if the test was
+ * successfully passed, and other negative error codes in case of other errors.
+ */
+static int torture_peb(const struct ubi_device *ubi, int pnum)
+{
+ void *buf;
+ int err, i, patt_count;
+
+ buf = kmalloc(ubi->peb_size, GFP_KERNEL);
+ if (unlikely(!buf))
+ return -ENOMEM;
+
+ patt_count = ARRAY_SIZE(patterns);
+ ubi_assert(patt_count > 0);
+
+ for (i = 0; i < patt_count; i++) {
+ err = do_sync_erase(ubi, pnum);
+ if (unlikely(err))
+ goto out;
+
+ /* Make sure the PEB contains only 0xFF bytes */
+ err = ubi_io_read(ubi, buf, pnum, 0, ubi->peb_size);
+ if (unlikely(err))
+ goto out;
+
+ err = check_pattern(buf, 0xFF, ubi->peb_size);
+ if (unlikely(err == 0)) {
+ ubi_err("erased PEB %d, but a non-0xFF byte found",
+ pnum);
+ err = -EIO;
+ goto out;
+ }
+
+ /* Write a pattern and check it */
+ memset(buf, patterns[i], ubi->peb_size);
+ err = ubi_io_write(ubi, buf, pnum, 0, ubi->peb_size);
+ if (unlikely(err))
+ goto out;
+
+ memset(buf, ~patterns[i], ubi->peb_size);
+ err = ubi_io_read(ubi, buf, pnum, 0, ubi->peb_size);
+ if (unlikely(err))
+ goto out;
+
+ err = check_pattern(buf, patterns[i], ubi->peb_size);
+ if (unlikely(err == 0)) {
+ ubi_err("pattern %x checking failed for PEB %d",
+ patterns[i], pnum);
+ err = -EIO;
+ goto out;
+ }
+ }
+
+ err = patt_count;
+
+out:
+ if (unlikely(err == UBI_IO_BITFLIPS || err == -EBADMSG))
+ /*
+ * If a bit-flip or data integrity error was detected, the test
+ * has not passed because it happened on a freshly erased
+ * physical eraseblock which means something is wrong with it.
+ */
+ err = -EIO;
+ kfree(buf);
+ return err;
+}
+
+/**
+ * ubi_io_sync_erase - synchronously erase a physical eraseblock.
+ * @ubi: UBI device description object
+ * @pnum: physical eraseblock number to erase
+ * @torture: if this physical eraseblock has to be tortured
+ *
+ * This function synchronously erases physical eraseblock @pnum. If @torture
+ * flag is not zero, the physical eraseblock is checked by means of writing
+ * different patterns to it and reading them back. If the torturing is enabled,
+ * the physical eraseblock is erased more then once.
+ *
+ * This function returns the number of erasures made in case of success, %-EIO
+ * if the erasure failed or the torturing test failed, and other negative error
+ * codes in case of other errors. Note, %-EIO means that the physical
+ * eraseblock is bad.
+ */
+int ubi_io_sync_erase(const struct ubi_device *ubi, int pnum, int torture)
+{
+ int err, ret = 0;
+
+ ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
+
+ err = paranoid_check_not_bad(ubi, pnum);
+ if (unlikely(err != 0))
+ return err > 0 ? -EINVAL : err;
+
+ if (unlikely(ubi->ro_mode)) {
+ ubi_err("read-only mode");
+ return -EROFS;
+ }
+
+ if (torture) {
+ ret = torture_peb(ubi, pnum);
+ if (unlikely(ret < 0))
+ return ret;
+ }
+
+ err = do_sync_erase(ubi, pnum);
+ if (unlikely(err))
+ return err;
+
+ return ret + 1;
+}
+
+/**
+ * ubi_io_is_bad - check if a physical eraseblock is bad.
+ * @ubi: UBI device description object
+ * @pnum: the physical eraseblock number to check
+ *
+ * This function returns a positive number if the physical eraseblock is bad,
+ * zero if not, and a negative error code if an error occurred.
+ */
+int ubi_io_is_bad(const struct ubi_device *ubi, int pnum)
+{
+ struct mtd_info *mtd = ubi->mtd;
+
+ ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
+
+ if (ubi->bad_allowed) {
+ int ret;
+
+ ret = mtd->block_isbad(mtd, (loff_t)pnum * ubi->peb_size);
+ if (unlikely(ret < 0))
+ ubi_err("error %d while checking if PEB %d is bad",
+ ret, pnum);
+ else if (ret)
+ dbg_io("PEB %d is bad", pnum);
+ return ret;
+ }
+
+ return 0;
+}
+
+/**
+ * ubi_io_mark_bad - mark a physical eraseblock as bad.
+ * @ubi: UBI device description object
+ * @pnum: the physical eraseblock number to mark
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum)
+{
+ int err;
+ struct mtd_info *mtd = ubi->mtd;
+
+ ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
+
+ if (unlikely(ubi->ro_mode)) {
+ ubi_err("read-only mode");
+ return -EROFS;
+ }
+
+ if (!ubi->bad_allowed)
+ return 0;
+
+ err = mtd->block_markbad(mtd, (loff_t)pnum * ubi->peb_size);
+ if (unlikely(err))
+ ubi_err("cannot mark PEB %d bad, error %d", pnum, err);
+ return err;
+}
+
+/**
+ * validate_ec_hdr - validate an erase counter header.
+ * @ubi: UBI device description object
+ * @ec_hdr: the erase counter header to check
+ *
+ * This function returns zero if the erase counter header is OK, and %1 if
+ * not.
+ */
+static int validate_ec_hdr(const struct ubi_device *ubi,
+ const struct ubi_ec_hdr *ec_hdr)
+{
+ long long ec;
+ int vid_hdr_offset, leb_start;
+
+ ec = ubi64_to_cpu(ec_hdr->ec);
+ vid_hdr_offset = ubi32_to_cpu(ec_hdr->vid_hdr_offset);
+ leb_start = ubi32_to_cpu(ec_hdr->data_offset);
+
+ if (unlikely(ec_hdr->version != UBI_VERSION)) {
+ ubi_err("node with incompatible UBI version found: "
+ "this UBI version is %d, image version is %d",
+ UBI_VERSION, (int)ec_hdr->version);
+ goto bad;
+ }
+
+ if (unlikely(vid_hdr_offset != ubi->vid_hdr_offset)) {
+ ubi_err("bad VID header offset %d, expected %d",
+ vid_hdr_offset, ubi->vid_hdr_offset);
+ goto bad;
+ }
+
+ if (unlikely(leb_start != ubi->leb_start)) {
+ ubi_err("bad data offset %d, expected %d",
+ leb_start, ubi->leb_start);
+ goto bad;
+ }
+
+ if (unlikely(ec < 0 || ec > UBI_MAX_ERASECOUNTER)) {
+ ubi_err("bad erase counter %lld", ec);
+ goto bad;
+ }
+
+ return 0;
+
+bad:
+ ubi_err("bad EC header");
+ ubi_dbg_dump_ec_hdr(ec_hdr);
+ ubi_dbg_dump_stack();
+ return 1;
+}
+
+/**
+ * ubi_io_read_ec_hdr - read and check an erase counter header.
+ * @ubi: UBI device description object
+ * @pnum: physical eraseblock to read from
+ * @ec_hdr: a &struct ubi_ec_hdr object where to store the read erase counter
+ * header
+ * @verbose: be verbose if the header is corrupted or was not found
+ *
+ * This function reads erase counter header from physical eraseblock @pnum and
+ * stores it in @ec_hdr. This function also checks CRC checksum of the read
+ * erase counter header. The following codes may be returned:
+ *
+ * o %0 if the CRC checksum is correct and the header was successfully read;
+ * o %UBI_IO_BITFLIPS if the CRC is correct, but bit-flips were detected
+ * and corrected by the flash driver; this is harmless but may indicate that
+ * this eraseblock may become bad soon (but may be not);
+ * o %UBI_IO_BAD_EC_HDR if the erase counter header is corrupted (a CRC error);
+ * o %UBI_IO_PEB_EMPTY if the physical eraseblock is empty;
+ * o a negative error code in case of failure.
+ */
+int ubi_io_read_ec_hdr(const struct ubi_device *ubi, int pnum,
+ struct ubi_ec_hdr *ec_hdr, int verbose)
+{
+ int err, read_err = 0;
+ uint32_t crc, magic, hdr_crc;
+
+ dbg_io("read EC header from PEB %d", pnum);
+ ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
+
+ err = ubi_io_read(ubi, ec_hdr, pnum, 0, UBI_EC_HDR_SIZE);
+ if (unlikely(err)) {
+ if (err != UBI_IO_BITFLIPS && err != -EBADMSG)
+ return err;
+
+ /*
+ * We read all the data, but either a correctable bit-flip
+ * occurred, or MTD reported about some data integrity error,
+ * like an ECC error in case of NAND. The former is harmless,
+ * the later may mean that the read data is corrupted. But we
+ * have a CRC check-sum and we will detect this. If the EC
+ * header is still OK, we just report this as there was a
+ * bit-flip.
+ */
+ read_err = err;
+ }
+
+ magic = ubi32_to_cpu(ec_hdr->magic);
+ if (unlikely(magic != UBI_EC_HDR_MAGIC)) {
+ /*
+ * The magic field is wrong. Let's check if we have read all
+ * 0xFF. If yes, this physical eraseblock is assumed to be
+ * empty.
+ *
+ * But if there was a read error, we do not test it for all
+ * 0xFFs. Even if it does contain all 0xFFs, this error
+ * indicates that something is still wrong with this physical
+ * eraseblock and we anyway cannot treat it as empty.
+ */
+ if (read_err != -EBADMSG &&
+ check_pattern(ec_hdr, 0xFF, UBI_EC_HDR_SIZE)) {
+ /* The physical eraseblock is supposedly empty */
+
+ /*
+ * The below is just a paranoid check, it has to be
+ * compiled out if paranoid checks are disabled.
+ */
+ err = paranoid_check_all_ff(ubi, pnum, 0,
+ ubi->peb_size);
+ if (unlikely(err))
+ return err > 0 ? UBI_IO_BAD_EC_HDR : err;
+
+ if (verbose)
+ ubi_warn("no EC header found at PEB %d, "
+ "only 0xFF bytes", pnum);
+ return UBI_IO_PEB_EMPTY;
+ }
+
+ /*
+ * This is not a valid erase counter header, and these are not
+ * 0xFF bytes. Report that the header is corrupted.
+ */
+ if (verbose) {
+ ubi_warn("bad magic number at PEB %d: %08x instead of "
+ "%08x", pnum, magic, UBI_EC_HDR_MAGIC);
+ ubi_dbg_dump_ec_hdr(ec_hdr);
+ }
+ return UBI_IO_BAD_EC_HDR;
+ }
+
+ crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC);
+ hdr_crc = ubi32_to_cpu(ec_hdr->hdr_crc);
+
+ if (unlikely(hdr_crc != crc)) {
+ if (verbose) {
+ ubi_warn("bad EC header CRC at PEB %d, calculated %#08x,"
+ " read %#08x", pnum, crc, hdr_crc);
+ ubi_dbg_dump_ec_hdr(ec_hdr);
+ }
+ return UBI_IO_BAD_EC_HDR;
+ }
+
+ /* And of course validate what has just been read from the media */
+ err = validate_ec_hdr(ubi, ec_hdr);
+ if (unlikely(err)) {
+ ubi_err("validation failed for PEB %d", pnum);
+ return -EINVAL;
+ }
+
+ return read_err ? UBI_IO_BITFLIPS : 0;
+}
+
+/**
+ * ubi_io_write_ec_hdr - write an erase counter header.
+ * @ubi: UBI device description object
+ * @pnum: physical eraseblock to write to
+ * @ec_hdr: the erase counter header to write
+ *
+ * This function writes erase counter header described by @ec_hdr to physical
+ * eraseblock @pnum. It also fills most fields of @ec_hdr before writing, so
+ * the caller do not have to fill them. Callers must only fill the @ec_hdr->ec
+ * field.
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure. If %-EIO is returned, the physical eraseblock most probably
+ * went bad.
+ */
+int ubi_io_write_ec_hdr(const struct ubi_device *ubi, int pnum,
+ struct ubi_ec_hdr *ec_hdr)
+{
+ int err;
+ uint32_t crc;
+
+ dbg_io("write EC header to PEB %d", pnum);
+ ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
+
+ ec_hdr->magic = cpu_to_ubi32(UBI_EC_HDR_MAGIC);
+ ec_hdr->version = UBI_VERSION;
+ ec_hdr->vid_hdr_offset = cpu_to_ubi32(ubi->vid_hdr_offset);
+ ec_hdr->data_offset = cpu_to_ubi32(ubi->leb_start);
+ crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC);
+ ec_hdr->hdr_crc = cpu_to_ubi32(crc);
+
+ err = paranoid_check_ec_hdr(ubi, pnum, ec_hdr);
+ if (unlikely(err))
+ return -EINVAL;
+
+ err = ubi_io_write(ubi, ec_hdr, pnum, 0, ubi->ec_hdr_alsize);
+ return err;
+}
+
+/**
+ * validate_vid_hdr - validate a volume identifier header.
+ * @ubi: UBI device description object
+ * @vid_hdr: the volume identifier header to check
+ *
+ * This function checks that data stored in the volume identifier header
+ * @vid_hdr. Returns zero if the VID header is OK and %1 if not.
+ */
+static int validate_vid_hdr(const struct ubi_device *ubi,
+ const struct ubi_vid_hdr *vid_hdr)
+{
+ int vol_type = vid_hdr->vol_type;
+ int copy_flag = vid_hdr->copy_flag;
+ int vol_id = ubi32_to_cpu(vid_hdr->vol_id);
+ int lnum = ubi32_to_cpu(vid_hdr->lnum);
+ int compat = vid_hdr->compat;
+ int data_size = ubi32_to_cpu(vid_hdr->data_size);
+ int used_ebs = ubi32_to_cpu(vid_hdr->used_ebs);
+ int data_pad = ubi32_to_cpu(vid_hdr->data_pad);
+ int data_crc = ubi32_to_cpu(vid_hdr->data_crc);
+ int usable_leb_size = ubi->leb_size - data_pad;
+
+ if (unlikely(copy_flag != 0 && copy_flag != 1)) {
+ dbg_err("bad copy_flag");
+ goto bad;
+ }
+
+ if (unlikely(vol_id < 0 || lnum < 0 || data_size < 0 || used_ebs < 0 ||
+ data_pad < 0)) {
+ dbg_err("negative values");
+ goto bad;
+ }
+
+ if (unlikely(vol_id >= UBI_MAX_VOLUMES &&
+ vol_id < UBI_INTERNAL_VOL_START)) {
+ dbg_err("bad vol_id");
+ goto bad;
+ }
+
+ if (unlikely(vol_id < UBI_INTERNAL_VOL_START && compat != 0)) {
+ dbg_err("bad compat");
+ goto bad;
+ }
+
+ if (unlikely(vol_id >= UBI_INTERNAL_VOL_START &&
+ compat != UBI_COMPAT_DELETE &&
+ compat != UBI_COMPAT_RO &&
+ compat != UBI_COMPAT_PRESERVE &&
+ compat != UBI_COMPAT_REJECT)) {
+ dbg_err("bad compat");
+ goto bad;
+ }
+
+ if (unlikely(vol_type != UBI_VID_DYNAMIC &&
+ vol_type != UBI_VID_STATIC)) {
+ dbg_err("bad vol_type");
+ goto bad;
+ }
+
+ if (unlikely(data_pad >= ubi->leb_size / 2)) {
+ dbg_err("bad data_pad");
+ goto bad;
+ }
+
+ if (vol_type == UBI_VID_STATIC) {
+ /*
+ * Although from high-level point of view static volumes may
+ * contain zero bytes of data, but no VID headers can contain
+ * zero at these fields, because they empty volumes do not have
+ * mapped logical eraseblocks.
+ */
+ if (unlikely(used_ebs == 0)) {
+ dbg_err("zero used_ebs");
+ goto bad;
+ }
+ if (unlikely(data_size == 0)) {
+ dbg_err("zero data_size");
+ goto bad;
+ }
+ if (lnum < used_ebs - 1) {
+ if (unlikely(data_size != usable_leb_size)) {
+ dbg_err("bad data_size");
+ goto bad;
+ }
+ } else if (lnum == used_ebs - 1) {
+ if (unlikely(data_size == 0)) {
+ dbg_err("bad data_size at last LEB");
+ goto bad;
+ }
+ } else {
+ dbg_err("too high lnum");
+ goto bad;
+ }
+ } else {
+ if (copy_flag == 0) {
+ if (unlikely(data_crc != 0)) {
+ dbg_err("non-zero data CRC");
+ goto bad;
+ }
+ if (unlikely(data_size != 0)) {
+ dbg_err("non-zero data_size");
+ goto bad;
+ }
+ } else {
+ if (unlikely(data_size == 0)) {
+ dbg_err("zero data_size of copy");
+ goto bad;
+ }
+ }
+ if (unlikely(used_ebs != 0)) {
+ dbg_err("bad used_ebs");
+ goto bad;
+ }
+ }
+
+ return 0;
+
+bad:
+ ubi_err("bad VID header");
+ ubi_dbg_dump_vid_hdr(vid_hdr);
+ ubi_dbg_dump_stack();
+ return 1;
+}
+
+/**
+ * ubi_io_read_vid_hdr - read and check a volume identifier header.
+ * @ubi: UBI device description object
+ * @pnum: physical eraseblock number to read from
+ * @vid_hdr: &struct ubi_vid_hdr object where to store the read volume
+ * identifier header
+ * @verbose: be verbose if the header is corrupted or wasn't found
+ *
+ * This function reads the volume identifier header from physical eraseblock
+ * @pnum and stores it in @vid_hdr. It also checks CRC checksum of the read
+ * volume identifier header. The following codes may be returned:
+ *
+ * o %0 if the CRC checksum is correct and the header was successfully read;
+ * o %UBI_IO_BITFLIPS if the CRC is correct, but bit-flips were detected
+ * and corrected by the flash driver; this is harmless but may indicate that
+ * this eraseblock may become bad soon;
+ * o %UBI_IO_BAD_VID_HRD if the volume identifier header is corrupted (a CRC
+ * error detected);
+ * o %UBI_IO_PEB_FREE if the physical eraseblock is free (i.e., there is no VID
+ * header there);
+ * o a negative error code in case of failure.
+ */
+int ubi_io_read_vid_hdr(const struct ubi_device *ubi, int pnum,
+ struct ubi_vid_hdr *vid_hdr, int verbose)
+{
+ int err, read_err = 0;
+ uint32_t crc, magic, hdr_crc;
+ void *p;
+
+ dbg_io("read VID header from PEB %d", pnum);
+ ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
+
+ p = (char *)vid_hdr - ubi->vid_hdr_shift;
+ err = ubi_io_read(ubi, p, pnum, ubi->vid_hdr_aloffset,
+ ubi->vid_hdr_alsize);
+ if (unlikely(err)) {
+ if (err != UBI_IO_BITFLIPS && err != -EBADMSG)
+ return err;
+
+ /*
+ * We read all the data, but either a correctable bit-flip
+ * occurred, or MTD reported about some data integrity error,
+ * like an ECC error in case of NAND. The former is harmless,
+ * the later may mean the read data is corrupted. But we have a
+ * CRC check-sum and we will identify this. If the VID header is
+ * still OK, we just report this as there was a bit-flip.
+ */
+ read_err = err;
+ }
+
+ magic = ubi32_to_cpu(vid_hdr->magic);
+ if (unlikely(magic != UBI_VID_HDR_MAGIC)) {
+ /*
+ * If we have read all 0xFF bytes, the VID header probably does
+ * not exist and the physical eraseblock is assumed to be free.
+ *
+ * But if there was a read error, we do not test the data for
+ * 0xFFs. Even if it does contain all 0xFFs, this error
+ * indicates that something is still wrong with this physical
+ * eraseblock and it cannot be regarded as free.
+ */
+ if (likely(read_err != -EBADMSG) &&
+ check_pattern(vid_hdr, 0xFF, UBI_VID_HDR_SIZE)) {
+ /* The physical eraseblock is supposedly free */
+
+ /*
+ * The below is just a paranoid check, it has to be
+ * compiled out if paranoid checks are disabled.
+ */
+ err = paranoid_check_all_ff(ubi, pnum, ubi->leb_start,
+ ubi->leb_size);
+ if (unlikely(err))
+ return err > 0 ? UBI_IO_BAD_VID_HDR : err;
+
+ if (verbose)
+ ubi_warn("no VID header found at PEB %d, "
+ "only 0xFF bytes", pnum);
+ return UBI_IO_PEB_FREE;
+ }
+
+ /*
+ * This is not a valid VID header, and these are not 0xFF
+ * bytes. Report that the header is corrupted.
+ */
+ if (verbose) {
+ ubi_warn("bad magic number at PEB %d: %08x instead of "
+ "%08x", pnum, magic, UBI_VID_HDR_MAGIC);
+ ubi_dbg_dump_vid_hdr(vid_hdr);
+ }
+ return UBI_IO_BAD_VID_HDR;
+ }
+
+ crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC);
+ hdr_crc = ubi32_to_cpu(vid_hdr->hdr_crc);
+
+ if (unlikely(hdr_crc != crc)) {
+ if (verbose) {
+ ubi_warn("bad CRC at PEB %d, calculated %#08x, "
+ "read %#08x", pnum, crc, hdr_crc);
+ ubi_dbg_dump_vid_hdr(vid_hdr);
+ }
+ return UBI_IO_BAD_VID_HDR;
+ }
+
+ /* Validate the VID header that we have just read */
+ err = validate_vid_hdr(ubi, vid_hdr);
+ if (unlikely(err)) {
+ ubi_err("validation failed for PEB %d", pnum);
+ return -EINVAL;
+ }
+
+ return read_err ? UBI_IO_BITFLIPS : 0;
+}
+
+/**
+ * ubi_io_write_vid_hdr - write a volume identifier header.
+ * @ubi: UBI device description object
+ * @pnum: the physical eraseblock number to write to
+ * @vid_hdr: the volume identifier header to write
+ *
+ * This function writes the volume identifier header described by @vid_hdr to
+ * physical eraseblock @pnum. This function automatically fills the
+ * @vid_hdr->magic and the @vid_hdr->version fields, as well as calculates
+ * header CRC checksum and stores it at vid_hdr->hdr_crc.
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure. If %-EIO is returned, the physical eraseblock probably went
+ * bad.
+ */
+int ubi_io_write_vid_hdr(const struct ubi_device *ubi, int pnum,
+ struct ubi_vid_hdr *vid_hdr)
+{
+ int err;
+ uint32_t crc;
+ void *p;
+
+ dbg_io("write VID header to PEB %d", pnum);
+ ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
+
+ err = paranoid_check_peb_ec_hdr(ubi, pnum);
+ if (unlikely(err))
+ return err > 0 ? -EINVAL: err;
+
+ vid_hdr->magic = cpu_to_ubi32(UBI_VID_HDR_MAGIC);
+ vid_hdr->version = UBI_VERSION;
+ crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC);
+ vid_hdr->hdr_crc = cpu_to_ubi32(crc);
+
+ err = paranoid_check_vid_hdr(ubi, pnum, vid_hdr);
+ if (unlikely(err))
+ return -EINVAL;
+
+ p = (char *)vid_hdr - ubi->vid_hdr_shift;
+ err = ubi_io_write(ubi, p, pnum, ubi->vid_hdr_aloffset,
+ ubi->vid_hdr_alsize);
+ return err;
+}
+
+#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
+
+/**
+ * paranoid_check_not_bad - ensure that a physical eraseblock is not bad.
+ * @ubi: UBI device description object
+ * @pnum: physical eraseblock number to check
+ *
+ * This function returns zero if the physical eraseblock is good, a positive
+ * number if it is bad and a negative error code if an error occurred.
+ */
+static int paranoid_check_not_bad(const struct ubi_device *ubi, int pnum)
+{
+ int err;
+
+ err = ubi_io_is_bad(ubi, pnum);
+ if (likely(!err))
+ return err;
+
+ ubi_err("paranoid check failed for PEB %d", pnum);
+ ubi_dbg_dump_stack();
+ return err;
+}
+
+/**
+ * paranoid_check_ec_hdr - check if an erase counter header is all right.
+ * @ubi: UBI device description object
+ * @pnum: physical eraseblock number the erase counter header belongs to
+ * @ec_hdr: the erase counter header to check
+ *
+ * This function returns zero if the erase counter header contains valid
+ * values, and %1 if not.
+ */
+static int paranoid_check_ec_hdr(const struct ubi_device *ubi, int pnum,
+ const struct ubi_ec_hdr *ec_hdr)
+{
+ int err;
+ uint32_t magic;
+
+ magic = ubi32_to_cpu(ec_hdr->magic);
+ if (unlikely(magic != UBI_EC_HDR_MAGIC)) {
+ ubi_err("bad magic %#08x, must be %#08x",
+ magic, UBI_EC_HDR_MAGIC);
+ goto fail;
+ }
+
+ err = validate_ec_hdr(ubi, ec_hdr);
+ if (unlikely(err)) {
+ ubi_err("paranoid check failed for PEB %d", pnum);
+ goto fail;
+ }
+
+ return 0;
+
+fail:
+ ubi_dbg_dump_ec_hdr(ec_hdr);
+ ubi_dbg_dump_stack();
+ return 1;
+}
+
+/**
+ * paranoid_check_peb_ec_hdr - check that the erase counter header of a
+ * physical eraseblock is in-place and is all right.
+ * @ubi: UBI device description object
+ * @pnum: the physical eraseblock number to check
+ *
+ * This function returns zero if the erase counter header is all right, %1 if
+ * not, and a negative error code if an error occurred.
+ */
+static int paranoid_check_peb_ec_hdr(const struct ubi_device *ubi, int pnum)
+{
+ int err;
+ uint32_t crc, hdr_crc;
+ struct ubi_ec_hdr *ec_hdr;
+
+ ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
+ if (unlikely(!ec_hdr))
+ return -ENOMEM;
+
+ err = ubi_io_read(ubi, ec_hdr, pnum, 0, UBI_EC_HDR_SIZE);
+ if (unlikely(err) && err != UBI_IO_BITFLIPS && err != -EBADMSG)
+ goto exit;
+
+ crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC);
+ hdr_crc = ubi32_to_cpu(ec_hdr->hdr_crc);
+ if (unlikely(hdr_crc != crc)) {
+ ubi_err("bad CRC, calculated %#08x, read %#08x", crc, hdr_crc);
+ ubi_err("paranoid check failed for PEB %d", pnum);
+ ubi_dbg_dump_ec_hdr(ec_hdr);
+ ubi_dbg_dump_stack();
+ err = 1;
+ goto exit;
+ }
+
+ err = paranoid_check_ec_hdr(ubi, pnum, ec_hdr);
+
+exit:
+ kfree(ec_hdr);
+ return err;
+}
+
+/**
+ * paranoid_check_vid_hdr - check that a volume identifier header is all right.
+ * @ubi: UBI device description object
+ * @pnum: physical eraseblock number the volume identifier header belongs to
+ * @vid_hdr: the volume identifier header to check
+ *
+ * This function returns zero if the volume identifier header is all right, and
+ * %1 if not.
+ */
+static int paranoid_check_vid_hdr(const struct ubi_device *ubi, int pnum,
+ const struct ubi_vid_hdr *vid_hdr)
+{
+ int err;
+ uint32_t magic;
+
+ magic = ubi32_to_cpu(vid_hdr->magic);
+ if (unlikely(magic != UBI_VID_HDR_MAGIC)) {
+ ubi_err("bad VID header magic %#08x at PEB %d, must be %#08x",
+ magic, pnum, UBI_VID_HDR_MAGIC);
+ goto fail;
+ }
+
+ err = validate_vid_hdr(ubi, vid_hdr);
+ if (unlikely(err)) {
+ ubi_err("paranoid check failed for PEB %d", pnum);
+ goto fail;
+ }
+
+ return err;
+
+fail:
+ ubi_err("paranoid check failed for PEB %d", pnum);
+ ubi_dbg_dump_vid_hdr(vid_hdr);
+ ubi_dbg_dump_stack();
+ return 1;
+
+}
+
+/**
+ * paranoid_check_peb_vid_hdr - check that the volume identifier header of a
+ * physical eraseblock is in-place and is all right.
+ * @ubi: UBI device description object
+ * @pnum: the physical eraseblock number to check
+ *
+ * This function returns zero if the volume identifier header is all right,
+ * %1 if not, and a negative error code if an error occurred.
+ */
+static int paranoid_check_peb_vid_hdr(const struct ubi_device *ubi, int pnum)
+{
+ int err;
+ uint32_t crc, hdr_crc;
+ struct ubi_vid_hdr *vid_hdr;
+ void *p;
+
+ vid_hdr = ubi_zalloc_vid_hdr(ubi);
+ if (unlikely(!vid_hdr))
+ return -ENOMEM;
+
+ p = (char *)vid_hdr - ubi->vid_hdr_shift;
+ err = ubi_io_read(ubi, p, pnum, ubi->vid_hdr_aloffset,
+ ubi->vid_hdr_alsize);
+ if (unlikely(err) && err != UBI_IO_BITFLIPS && err != -EBADMSG)
+ goto exit;
+
+ crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_EC_HDR_SIZE_CRC);
+ hdr_crc = ubi32_to_cpu(vid_hdr->hdr_crc);
+ if (unlikely(hdr_crc != crc)) {
+ ubi_err("bad VID header CRC at PEB %d, calculated %#08x, "
+ "read %#08x", pnum, crc, hdr_crc);
+ ubi_err("paranoid check failed for PEB %d", pnum);
+ ubi_dbg_dump_vid_hdr(vid_hdr);
+ ubi_dbg_dump_stack();
+ err = 1;
+ goto exit;
+ }
+
+ err = paranoid_check_vid_hdr(ubi, pnum, vid_hdr);
+
+exit:
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return err;
+}
+
+/**
+ * paranoid_check_all_ff - check that a region of flash is empty.
+ * @ubi: UBI device description object
+ * @pnum: the physical eraseblock number to check
+ * @offset: the starting offset within the physical eraseblock to check
+ * @len: the length of the region to check
+ *
+ * This function returns zero if only 0xFF bytes are present at offset
+ * @offset of the physical eraseblock @pnum, %1 if not, and a negative error
+ * code if an error occurred.
+ */
+static int paranoid_check_all_ff(const struct ubi_device *ubi, int pnum,
+ int offset, int len)
+{
+ size_t read;
+ int err;
+ void *buf;
+ loff_t addr = (loff_t)pnum * ubi->peb_size + offset;
+
+ buf = kzalloc(len, GFP_KERNEL);
+ if (unlikely(!buf))
+ return -ENOMEM;
+
+ err = ubi->mtd->read(ubi->mtd, addr, len, &read, buf);
+ if (unlikely(err && err != -EUCLEAN)) {
+ ubi_err("error %d while reading %d bytes from PEB %d:%d, "
+ "read %zd bytes", err, len, pnum, offset, read);
+ goto error;
+ }
+
+ err = check_pattern(buf, 0xFF, len);
+ if (unlikely(err == 0)) {
+ ubi_err("flash region at PEB %d:%d, length %d does not "
+ "contain all 0xFF bytes", pnum, offset, len);
+ goto fail;
+ }
+
+ kfree(buf);
+ return 0;
+
+fail:
+ ubi_err("paranoid check failed for PEB %d", pnum);
+ dbg_err("hex dump of the %d-%d region", offset, offset + len);
+ ubi_dbg_hexdump(buf, len);
+ err = 1;
+error:
+ ubi_dbg_dump_stack();
+ kfree(buf);
+ return err;
+}
+
+#endif /* CONFIG_MTD_UBI_DEBUG_PARANOID */
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 08/20 take 4] UBI: volume table unit
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (6 preceding siblings ...)
2007-03-23 16:43 ` [PATCH 07/20 take 4] UBI: I/O unit Artem Bityutskiy
@ 2007-03-23 16:43 ` Artem Bityutskiy
2007-03-23 16:43 ` [PATCH 09/20 take 4] UBI: wear-leveling unit Artem Bityutskiy
` (11 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:43 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 23988 bytes --]
diff -auNrp tmp-from/drivers/mtd/ubi/vtbl.c tmp-to/drivers/mtd/ubi/vtbl.c
--- tmp-from/drivers/mtd/ubi/vtbl.c 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/vtbl.c 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,809 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ * Copyright (c) Nokia Corporation, 2006, 2007
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file includes volume table manipulation code. The volume table is an
+ * on-flash table containing volume meta-data like name, number of reserved
+ * physical eraseblocks, type, etc. The volume table is stored in the so-called
+ * "layout volume".
+ *
+ * The layout volume is an internal volume which is organized as follows. It
+ * consists of two logical eraseblocks - LEB 0 and LEB 1. Each logical
+ * eraseblock stores one volume table copy, i.e. LEB 0 and LEB 1 duplicate each
+ * other. This redundancy guarantees robustness to unclean reboots. The volume
+ * table is basically an array of volume table records. Each record contains
+ * full information about the volume and protected by a CRC checksum.
+ *
+ * The volume table is changed, it is first changed in RAM. Then LEB 0 is
+ * erased, and the updated volume table is written back to LEB 0. Then same for
+ * LEB 1. This scheme guarantees recoverability from unclean reboots.
+ *
+ * In this UBI implementation the on-flash volume table does not contain any
+ * information about how many data static volumes contain. This information may
+ * be found from the scanning data.
+ *
+ * But it would still be beneficial to store this information in the volume
+ * table. For example, suppose we have a static volume X, and all its physical
+ * eraseblocks became bad for some reasons. Suppose we are attaching the
+ * corresponding MTD device, the scanning has found no logical eraseblocks
+ * corresponding to the volume X. According to the volume table volume X does
+ * exist. So we don't know whether it is just empty or all its physical
+ * eraseblocks went bad. So we cannot alarm the user about this corruption.
+ *
+ * The volume table also stores so-called "update marker", which is used for
+ * volume updates. Before updating the volume, the update marker is set, and
+ * after the update operation is finished, the update marker is cleared. So if
+ * the update operation was interrupted (e.g. by an unclean reboot) - the
+ * update marker is still there and we know that the volume's contents is
+ * damaged.
+ */
+
+#include <linux/crc32.h>
+#include <linux/err.h>
+#include <asm/div64.h>
+#include "ubi.h"
+
+#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
+static void paranoid_vtbl_check(const struct ubi_device *ubi);
+#else
+#define paranoid_vtbl_check(ubi)
+#endif
+
+/* Empty volume table record */
+struct ubi_vtbl_record empty_vtbl_record;
+
+/**
+ * ubi_change_vtbl_record - change volume table record.
+ * @ubi: UBI device description object
+ * @idx: table index to change
+ * @vtbl_rec: new volume table record
+ *
+ * This function changes volume table record @idx. If @vtbl_rec is %NULL, empty
+ * volume table record is written. The caller does not have to calculate CRC of
+ * the record as it is done by this function. Returns zero in case of success
+ * and a negative error code in case of failure.
+ */
+int ubi_change_vtbl_record(struct ubi_device *ubi, int idx,
+ struct ubi_vtbl_record *vtbl_rec)
+{
+ int i, err;
+ uint32_t crc;
+
+ ubi_assert(idx >= 0 && idx < ubi->vtbl_slots);
+
+ if (!vtbl_rec)
+ vtbl_rec = &empty_vtbl_record;
+ else {
+ crc = crc32(UBI_CRC32_INIT, vtbl_rec, UBI_VTBL_RECORD_SIZE_CRC);
+ vtbl_rec->crc = cpu_to_ubi32(crc);
+ }
+
+ dbg_msg("change record %d", idx);
+ ubi_dbg_dump_vtbl_record(vtbl_rec, idx);
+
+ mutex_lock(&ubi->vtbl_mutex);
+ memcpy(&ubi->vtbl[idx], vtbl_rec, sizeof(struct ubi_vtbl_record));
+ for (i = 0; i < UBI_LAYOUT_VOLUME_EBS; i++) {
+ err = ubi_eba_unmap_leb(ubi, UBI_LAYOUT_VOL_ID, i);
+ if (err) {
+ mutex_unlock(&ubi->vtbl_mutex);
+ return err;
+ }
+ err = ubi_eba_write_leb(ubi, UBI_LAYOUT_VOL_ID, i, ubi->vtbl, 0,
+ ubi->vtbl_size, UBI_DATA_LONGTERM);
+ if (err) {
+ mutex_unlock(&ubi->vtbl_mutex);
+ return err;
+ }
+ }
+
+ paranoid_vtbl_check(ubi);
+ mutex_unlock(&ubi->vtbl_mutex);
+ return ubi_wl_flush(ubi);
+}
+
+/**
+ * vol_til_check - check if volume table is not corrupted and contains sensible
+ * data.
+ *
+ * @ubi: UBI device description object
+ * @vtbl: volume table
+ *
+ * This function returns zero if @vtbl is all right, %1 if CRC is incorrect,
+ * and %-EINVAL if it contains inconsistent data.
+ */
+static int vtbl_check(const struct ubi_device *ubi,
+ const struct ubi_vtbl_record *vtbl)
+{
+ int i, n, reserved_pebs, alignment, data_pad, vol_type, name_len;
+ int upd_marker;
+ uint32_t crc;
+ const char *name;
+
+ for (i = 0; i < ubi->vtbl_slots; i++) {
+ cond_resched();
+
+ reserved_pebs = ubi32_to_cpu(vtbl[i].reserved_pebs);
+ alignment = ubi32_to_cpu(vtbl[i].alignment);
+ data_pad = ubi32_to_cpu(vtbl[i].data_pad);
+ upd_marker = vtbl[i].upd_marker;
+ vol_type = vtbl[i].vol_type;
+ name_len = ubi16_to_cpu(vtbl[i].name_len);
+ name = &vtbl[i].name[0];
+
+ crc = crc32(UBI_CRC32_INIT, &vtbl[i], UBI_VTBL_RECORD_SIZE_CRC);
+ if (ubi32_to_cpu(vtbl[i].crc) != crc) {
+ ubi_err("bad CRC at record %u: %#08x, not %#08x",
+ i, crc, ubi32_to_cpu(vtbl[i].crc));
+ ubi_dbg_dump_vtbl_record(&vtbl[i], i);
+ return 1;
+ }
+
+ if (reserved_pebs == 0) {
+ if (memcmp(&vtbl[i], &empty_vtbl_record,
+ UBI_VTBL_RECORD_SIZE)) {
+ dbg_err("bad empty record");
+ goto bad;
+ }
+ continue;
+ }
+
+ if (reserved_pebs < 0 || alignment < 0 || data_pad < 0 ||
+ name_len < 0) {
+ dbg_err("negative values");
+ goto bad;
+ }
+
+ if (alignment > ubi->leb_size || alignment == 0) {
+ dbg_err("bad alignment");
+ goto bad;
+ }
+
+ n = alignment % ubi->min_io_size;
+ if (alignment != 1 && n) {
+ dbg_err("alignment is not multiple of min I/O unit");
+ goto bad;
+ }
+
+ n = ubi->leb_size % alignment;
+ if (data_pad != n) {
+ dbg_err("bad data_pad, has to be %d", n);
+ goto bad;
+ }
+
+ if (vol_type != UBI_VID_DYNAMIC && vol_type != UBI_VID_STATIC) {
+ dbg_err("bad vol_type");
+ goto bad;
+ }
+
+ if (upd_marker != 0 && upd_marker != 1) {
+ dbg_err("bad upd_marker");
+ goto bad;
+ }
+
+ if (reserved_pebs > ubi->good_peb_count) {
+ dbg_err("too large reserved_pebs, good PEBs %d",
+ ubi->good_peb_count);
+ goto bad;
+ }
+
+ if (name_len > UBI_VOL_NAME_MAX) {
+ dbg_err("too long volume name, max %d",
+ UBI_VOL_NAME_MAX);
+ goto bad;
+ }
+
+ if (name[0] == '\0') {
+ dbg_err("NULL volume name");
+ goto bad;
+ }
+
+ if (name_len != strnlen(name, name_len + 1)) {
+ dbg_err("bad name_len");
+ goto bad;
+ }
+ }
+
+ /* Checks that all names are unique */
+ for (i = 0; i < ubi->vtbl_slots - 1; i++) {
+ for (n = i + 1; n < ubi->vtbl_slots; n++) {
+ int len1 = ubi16_to_cpu(vtbl[i].name_len);
+ int len2 = ubi16_to_cpu(vtbl[n].name_len);
+
+ if (len1 > 0 && len1 == len2 &&
+ !strncmp(vtbl[i].name, vtbl[n].name, len1)) {
+ ubi_err("volumes %d and %d have the same name"
+ " \"%s\"", i, n, vtbl[i].name);
+ ubi_dbg_dump_vtbl_record(&vtbl[i], i);
+ ubi_dbg_dump_vtbl_record(&vtbl[n], n);
+ return -EINVAL;
+ }
+ }
+ }
+
+ return 0;
+
+bad:
+ ubi_err("volume table check failed, record %d", i);
+ ubi_dbg_dump_vtbl_record(&vtbl[i], i);
+ return -EINVAL;
+}
+
+/**
+ * create_vtbl - create a copy of volume table.
+ * @ubi: UBI device description object
+ * @si: scanning information
+ * @copy: number of the volume table copy
+ * @vtbl: contents of the volume table
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int create_vtbl(const struct ubi_device *ubi, struct ubi_scan_info *si,
+ int copy, void *vtbl)
+{
+ int err, tries = 0;
+ static struct ubi_vid_hdr *vid_hdr;
+ struct ubi_scan_volume *sv;
+ struct ubi_scan_leb *new_seb, *old_seb = NULL;
+
+ ubi_msg("create volume table (copy #%d)", copy + 1);
+
+ vid_hdr = ubi_zalloc_vid_hdr(ubi);
+ if (!vid_hdr)
+ return -ENOMEM;
+
+ /*
+ * Check if there is a logical eraseblock which would have to contain
+ * this volume table copy was found during scanning. It has to be wiped
+ * out.
+ */
+ sv = ubi_scan_find_sv(si, UBI_LAYOUT_VOL_ID);
+ if (sv)
+ old_seb = ubi_scan_find_seb(sv, copy);
+
+retry:
+ new_seb = ubi_scan_get_free_peb(ubi, si);
+ if (IS_ERR(new_seb)) {
+ err = PTR_ERR(new_seb);
+ goto out_free;
+ }
+
+ vid_hdr->vol_type = UBI_VID_DYNAMIC;
+ vid_hdr->vol_id = cpu_to_ubi32(UBI_LAYOUT_VOL_ID);
+ vid_hdr->compat = UBI_LAYOUT_VOLUME_COMPAT;
+ vid_hdr->data_size = vid_hdr->used_ebs =
+ vid_hdr->data_pad = cpu_to_ubi32(0);
+ vid_hdr->lnum = cpu_to_ubi32(copy);
+ vid_hdr->sqnum = cpu_to_ubi64(++si->max_sqnum);
+ vid_hdr->leb_ver = cpu_to_ubi32(old_seb ? old_seb->leb_ver + 1: 0);
+
+ /* The EC header is already there, write the VID header */
+ err = ubi_io_write_vid_hdr(ubi, new_seb->pnum, vid_hdr);
+ if (err)
+ goto write_error;
+
+ /* Write the layout volume contents */
+ err = ubi_io_write_data(ubi, vtbl, new_seb->pnum, 0, ubi->vtbl_size);
+ if (err)
+ goto write_error;
+
+ /*
+ * And add it to the scanning information. Don't delete the old
+ * @old_seb as it will be deleted and freed in 'ubi_scan_add_used()'.
+ */
+ err = ubi_scan_add_used(ubi, si, new_seb->pnum, new_seb->ec,
+ vid_hdr, 0);
+ kfree(new_seb);
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return err;
+
+write_error:
+ kfree(new_seb);
+ /* May be this physical eraseblock went bad, try to pick another one */
+ if (++tries <= 5) {
+ err = ubi_scan_add_to_list(si, new_seb->pnum, new_seb->ec,
+ &si->corr);
+ if (!err)
+ goto retry;
+ }
+out_free:
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return err;
+
+}
+
+/**
+ * process_lvol - process the layout volume.
+ * @ubi: UBI device description object
+ * @si: scanning information
+ * @sv: layout volume scanning information
+ *
+ * This function is responsible for reading the layout volume, ensuring it is
+ * not corrupted, and recovering from corruptions if needed. Returns volume
+ * table in case of success and a negative error code in case of failure.
+ */
+static struct ubi_vtbl_record *process_lvol(const struct ubi_device *ubi,
+ struct ubi_scan_info *si,
+ struct ubi_scan_volume *sv)
+{
+ int err;
+ struct rb_node *rb;
+ struct ubi_scan_leb *seb;
+ struct ubi_vtbl_record *leb[UBI_LAYOUT_VOLUME_EBS] = { NULL, NULL };
+ int leb_corrupted[UBI_LAYOUT_VOLUME_EBS] = {1, 1};
+
+ /*
+ * UBI goes through the following steps when it changes the layout
+ * volume:
+ * a. erase LEB 0;
+ * b. write new data to LEB 0;
+ * c. erase LEB 1;
+ * d. write new data to LEB 1.
+ *
+ * Before the change, both LEBs contain the same data.
+ *
+ * Due to unclean reboots, the contents of LEB 0 may be lost, but there
+ * should LEB 1. So it is OK if LEB 0 is corrupted while LEB 1 is not.
+ * Similarly, LEB 1 may be lost, but there should be LEB 0. And
+ * finally, unclean reboots may result in a situation when neither LEB
+ * 0 nor LEB 1 are corrupted, but they are different. In this case, LEB
+ * 0 contains more recent information.
+ *
+ * So the plan is to first check LEB 0. Then
+ * a. if LEB 0 is OK, it must be containing the most resent data; then
+ * we compare it with LEB 1, and if they are different, we copy LEB
+ * 0 to LEB 1;
+ * b. if LEB 0 is corrupted, but LEB 1 has to be OK, and we copy LEB 1
+ * to LEB 0.
+ */
+
+ dbg_msg("check layout volume");
+
+ /* Read both LEB 0 and LEB 1 into memory */
+ ubi_rb_for_each_entry(rb, seb, &sv->root, u.rb) {
+ leb[seb->lnum] = kzalloc(ubi->vtbl_size, GFP_KERNEL);
+ if (!leb[seb->lnum]) {
+ err = -ENOMEM;
+ goto out_free;
+ }
+
+ err = ubi_io_read_data(ubi, leb[seb->lnum], seb->pnum, 0,
+ ubi->vtbl_size);
+ if (err == UBI_IO_BITFLIPS || err == -EBADMSG)
+ /* Scrub the PEB later */
+ seb->scrub = 1;
+ else if (err)
+ goto out_free;
+ }
+
+ err = -EINVAL;
+ if (leb[0]) {
+ leb_corrupted[0] = vtbl_check(ubi, leb[0]);
+ if (leb_corrupted[0] < 0)
+ goto out_free;
+ }
+
+ if (!leb_corrupted[0]) {
+ /* LEB 0 is OK */
+ if (leb[1])
+ leb_corrupted[1] = memcmp(leb[0], leb[1], ubi->vtbl_size);
+ if (leb_corrupted[1]) {
+ ubi_warn("volume table copy #2 is corrupted");
+ err = create_vtbl(ubi, si, 1, leb[0]);
+ if (err)
+ goto out_free;
+ ubi_msg("volume table was restored");
+ }
+
+ /* Both LEB 1 and LEB 2 are OK and consistent */
+ kfree(leb[1]);
+ return leb[0];
+ } else {
+ /* LEB 0 is corrupted or does not exist */
+ if (leb[1]) {
+ leb_corrupted[1] = vtbl_check(ubi, leb[1]);
+ if (leb_corrupted[1] < 0)
+ goto out_free;
+ }
+ if (leb_corrupted[1]) {
+ /* Both LEB 0 and LEB 1 are corrupted */
+ ubi_err("both volume tables are corrupted");
+ goto out_free;
+ }
+
+ ubi_warn("volume table copy #1 is corrupted");
+ err = create_vtbl(ubi, si, 0, leb[1]);
+ if (err)
+ goto out_free;
+ ubi_msg("volume table was restored");
+
+ kfree(leb[0]);
+ return leb[1];
+ }
+
+out_free:
+ kfree(leb[0]);
+ kfree(leb[1]);
+ return ERR_PTR(err);
+}
+
+/**
+ * create_empty_lvol - create empty layout volume.
+ * @ubi: UBI device description object
+ * @si: scanning information
+ *
+ * This function returns volume table contents in case of success and a
+ * negative error code in case of failure.
+ */
+static struct ubi_vtbl_record *create_empty_lvol(const struct ubi_device *ubi,
+ struct ubi_scan_info *si)
+{
+ int i;
+ struct ubi_vtbl_record *vtbl;
+
+ vtbl = kzalloc(ubi->vtbl_size, GFP_KERNEL);
+ if (!vtbl)
+ return ERR_PTR(-ENOMEM);
+
+ for (i = 0; i < ubi->vtbl_slots; i++)
+ memcpy(&vtbl[i], &empty_vtbl_record, UBI_VTBL_RECORD_SIZE);
+
+ for (i = 0; i < UBI_LAYOUT_VOLUME_EBS; i++) {
+ int err;
+
+ err = create_vtbl(ubi, si, i, vtbl);
+ if (err) {
+ kfree(vtbl);
+ return ERR_PTR(err);
+ }
+ }
+
+ return vtbl;
+}
+
+/**
+ * init_volumes - initialize volume information for existing volumes.
+ * @ubi: UBI device description object
+ * @si: scanning information
+ * @vtbl: volume table
+ *
+ * This function allocates volume description objects for existing volumes.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int init_volumes(struct ubi_device *ubi, const struct ubi_scan_info *si,
+ const struct ubi_vtbl_record *vtbl)
+{
+ int i, reserved_pebs = 0;
+ struct ubi_scan_volume *sv;
+ struct ubi_volume *vol;
+
+ for (i = 0; i < ubi->vtbl_slots; i++) {
+ cond_resched();
+
+ if (ubi32_to_cpu(vtbl[i].reserved_pebs) == 0)
+ continue; /* Empty record */
+
+ vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL);
+ if (!vol)
+ return -ENOMEM;
+
+ vol->reserved_pebs = ubi32_to_cpu(vtbl[i].reserved_pebs);
+ vol->alignment = ubi32_to_cpu(vtbl[i].alignment);
+ vol->data_pad = ubi32_to_cpu(vtbl[i].data_pad);
+ vol->vol_type = vtbl[i].vol_type == UBI_VID_DYNAMIC ?
+ UBI_DYNAMIC_VOLUME : UBI_STATIC_VOLUME;
+ vol->name_len = ubi16_to_cpu(vtbl[i].name_len);
+ vol->usable_leb_size = ubi->leb_size - vol->data_pad;
+ memcpy(vol->name, vtbl[i].name, vol->name_len);
+ vol->name[vol->name_len] = '\0';
+ vol->vol_id = i;
+
+ ubi_assert(!ubi->volumes[i]);
+ ubi->volumes[i] = vol;
+ ubi->vol_count += 1;
+ vol->ubi = ubi;
+ reserved_pebs += vol->reserved_pebs;
+
+ /*
+ * In case of dynamic volume UBI knows nothing about how many
+ * data is stored there. So assume the whole volume is used.
+ */
+ if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
+ vol->used_ebs = vol->reserved_pebs;
+ vol->last_eb_bytes = vol->usable_leb_size;
+ vol->used_bytes = vol->used_ebs * vol->usable_leb_size;
+ continue;
+ }
+
+ /* Static volumes only */
+ sv = ubi_scan_find_sv(si, i);
+ if (!sv) {
+ /*
+ * No eraseblocks belonging to this volume found. We
+ * don't actually know whether this static volume is
+ * completely corrupted or just contains no data. And
+ * we cannot know this as long as data size is not
+ * stored on flash. So we just assume the volume is
+ * empty. FIXME: this should be handled.
+ */
+ continue;
+ }
+
+ if (unlikely(sv->leb_count != sv->used_ebs)) {
+ /*
+ * We found a static volume which misses several
+ * eraseblocks. Treat it as corrupted.
+ */
+ ubi_warn("static volume %d misses %d LEBs - corrupted",
+ sv->vol_id, sv->used_ebs - sv->leb_count);
+ vol->corrupted = 1;
+ continue;
+ }
+
+ vol->used_ebs = sv->used_ebs;
+ vol->used_bytes = (vol->used_ebs - 1) * vol->usable_leb_size;
+ vol->used_bytes += sv->last_data_size;
+ vol->last_eb_bytes = sv->last_data_size;
+ }
+
+ vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL);
+ if (!vol)
+ return -ENOMEM;
+
+ vol->reserved_pebs = UBI_LAYOUT_VOLUME_EBS;
+ vol->alignment = 1;
+ vol->vol_type = UBI_DYNAMIC_VOLUME;
+ vol->name_len = sizeof(UBI_LAYOUT_VOLUME_NAME) - 1;
+ memcpy(vol->name, UBI_LAYOUT_VOLUME_NAME, vol->name_len + 1);
+ vol->usable_leb_size = ubi->leb_size;
+ vol->used_ebs = vol->reserved_pebs;
+ vol->last_eb_bytes = vol->reserved_pebs;
+ vol->used_bytes = vol->used_ebs * (ubi->leb_size - vol->data_pad);
+ vol->vol_id = UBI_LAYOUT_VOL_ID;
+
+ ubi_assert(!ubi->volumes[i]);
+ ubi->volumes[vol_id2idx(ubi, vol->vol_id)] = vol;
+ reserved_pebs += vol->reserved_pebs;
+ ubi->vol_count += 1;
+ vol->ubi = ubi;
+
+ if (reserved_pebs > ubi->avail_pebs)
+ ubi_err("not enough PEBs, required %d, available %d",
+ reserved_pebs, ubi->avail_pebs);
+ ubi->rsvd_pebs += reserved_pebs;
+ ubi->avail_pebs -= reserved_pebs;
+
+ return 0;
+}
+
+/**
+ * check_sv - check volume scanning information.
+ * @vol: UBI volume description object
+ * @sv: volume scanning information
+ *
+ * This function returns zero if the volume scanning information is consistent
+ * to the data read from the volume tabla, and %-EINVAL if not.
+ */
+static int check_sv(const struct ubi_volume *vol,
+ const struct ubi_scan_volume *sv)
+{
+ if (sv->highest_lnum >= vol->reserved_pebs) {
+ dbg_err("bad highest_lnum");
+ goto bad;
+ }
+ if (sv->leb_count > vol->reserved_pebs) {
+ dbg_err("bad leb_count");
+ goto bad;
+ }
+ if (sv->vol_type != vol->vol_type) {
+ dbg_err("bad vol_type");
+ goto bad;
+ }
+ if (sv->used_ebs > vol->reserved_pebs) {
+ dbg_err("bad used_ebs");
+ goto bad;
+ }
+ if (sv->data_pad != vol->data_pad) {
+ dbg_err("bad data_pad");
+ goto bad;
+ }
+ return 0;
+
+bad:
+ ubi_err("bad scanning information");
+ ubi_dbg_dump_sv(sv);
+ ubi_dbg_dump_vol_info(vol);
+ return -EINVAL;
+}
+
+/**
+ * check_scanning_info - check that scanning information.
+ * @ubi: UBI device description object
+ * @si: scanning information
+ *
+ * Even though we protect on-flash data by CRC checksums, we still don't trust
+ * the media. This function ensures that scanning information is consistent to
+ * the information read from the volume table. Returns zero if the scanning
+ * information is OK and %-EINVAL if it is not.
+ */
+static int check_scanning_info(const struct ubi_device *ubi,
+ struct ubi_scan_info *si)
+{
+ int err, i;
+ struct ubi_scan_volume *sv;
+ struct ubi_volume *vol;
+
+ if (si->vols_found > UBI_INT_VOL_COUNT + ubi->vtbl_slots) {
+ ubi_err("scanning found %d volumes, maximum is %d + %d",
+ si->vols_found, UBI_INT_VOL_COUNT, ubi->vtbl_slots);
+ return -EINVAL;
+ }
+
+ if (si->highest_vol_id >= ubi->vtbl_slots + UBI_INT_VOL_COUNT&&
+ si->highest_vol_id < UBI_INTERNAL_VOL_START) {
+ ubi_err("too large volume ID %d found by scanning",
+ si->highest_vol_id);
+ return -EINVAL;
+ }
+
+
+ for (i = 0; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
+ cond_resched();
+
+ sv = ubi_scan_find_sv(si, i);
+ vol = ubi->volumes[i];
+ if (!vol) {
+ if (sv)
+ ubi_scan_rm_volume(si, sv);
+ continue;
+ }
+
+ if (vol->reserved_pebs == 0) {
+ ubi_assert(i < ubi->vtbl_slots);
+
+ if (!sv)
+ continue;
+
+ /*
+ * During scanning we found a volume which does not
+ * exist according to the information in the volume
+ * table. This must have happened due to an unclean
+ * reboot while the volume was being removed. Discard
+ * these eraseblocks.
+ */
+ ubi_msg("finish volume %d removal", sv->vol_id);
+ ubi_scan_rm_volume(si, sv);
+ } else if (sv) {
+ err = check_sv(vol, sv);
+ if (err)
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * ubi_read_volume_table - read volume table.
+ * information.
+ * @ubi: UBI device description object
+ * @si: scanning information
+ *
+ * This function reads volume table, checks it, recover from errors if needed,
+ * or creates it if needed. Returns zero in case of success and a negative
+ * error code in case of failure.
+ */
+int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_scan_info *si)
+{
+ int i, err;
+ struct ubi_scan_volume *sv;
+
+ empty_vtbl_record.crc = cpu_to_ubi32(0xf116c36b);
+
+ /*
+ * The number of supported volumes is limited by the eraseblock size
+ * and by the UBI_MAX_VOLUMES constant.
+ */
+ ubi->vtbl_slots = ubi->leb_size / UBI_VTBL_RECORD_SIZE;
+ if (ubi->vtbl_slots > UBI_MAX_VOLUMES)
+ ubi->vtbl_slots = UBI_MAX_VOLUMES;
+
+ ubi->vtbl_size = ubi->vtbl_slots * UBI_VTBL_RECORD_SIZE;
+ ubi->vtbl_size = ubi_align_up(ubi->vtbl_size, ubi->min_io_size);
+
+ sv = ubi_scan_find_sv(si, UBI_LAYOUT_VOL_ID);
+ if (!sv) {
+ /*
+ * No logical eraseblocks belonging to the layout volume were
+ * found. This could mean that the flash is just empty. In
+ * this case we create empty layout volume.
+ *
+ * But if flash is not empty this must be a corruption or the
+ * MTD device just contains garbage.
+ */
+ if (si->is_empty) {
+ ubi->vtbl = create_empty_lvol(ubi, si);
+ if (IS_ERR(ubi->vtbl))
+ return PTR_ERR(ubi->vtbl);
+ } else {
+ ubi_err("the layout volume was not found");
+ return -EINVAL;
+ }
+ } else {
+ if (sv->leb_count > UBI_LAYOUT_VOLUME_EBS) {
+ /* This must not happen with proper UBI images */
+ dbg_err("too many LEBs (%d) in layout volume",
+ sv->leb_count);
+ return -EINVAL;
+ }
+
+ ubi->vtbl = process_lvol(ubi, si, sv);
+ if (IS_ERR(ubi->vtbl))
+ return PTR_ERR(ubi->vtbl);
+ }
+
+ ubi->avail_pebs = ubi->good_peb_count;
+
+ /*
+ * The layout volume is OK, initialize the corresponding in-RAM data
+ * structures.
+ */
+ err = init_volumes(ubi, si, ubi->vtbl);
+ if (err)
+ goto out_free;
+
+ /*
+ * Get sure that the scanning information is consistent to the
+ * information stored in the volume table.
+ */
+ err = check_scanning_info(ubi, si);
+ if (err)
+ goto out_free;
+
+ return 0;
+
+out_free:
+ kfree(ubi->vtbl);
+ for (i = 0; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++)
+ if (ubi->volumes[i]) {
+ kfree(ubi->volumes[i]);
+ ubi->volumes[i] = NULL;
+ }
+ return err;
+}
+
+#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
+
+/**
+ * paranoid_vtbl_check - check volume table.
+ * @ubi: UBI device description object
+ */
+static void paranoid_vtbl_check(const struct ubi_device *ubi)
+{
+ if (vtbl_check(ubi, ubi->vtbl)) {
+ ubi_err("paranoid check failed");
+ BUG();
+ }
+}
+
+#endif /* CONFIG_MTD_UBI_DEBUG_PARANOID */
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 09/20 take 4] UBI: wear-leveling unit
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (7 preceding siblings ...)
2007-03-23 16:43 ` [PATCH 08/20 take 4] UBI: volume table unit Artem Bityutskiy
@ 2007-03-23 16:43 ` Artem Bityutskiy
2007-03-26 12:34 ` Frank Haverkamp
2007-03-23 16:43 ` [PATCH 10/20 take 4] UBI: EBA unit Artem Bityutskiy
` (10 subsequent siblings)
19 siblings, 1 reply; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:43 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 47273 bytes --]
diff -auNrp tmp-from/drivers/mtd/ubi/wl.c tmp-to/drivers/mtd/ubi/wl.c
--- tmp-from/drivers/mtd/ubi/wl.c 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/wl.c 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,1698 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём), Thomas Gleixner
+ */
+
+/*
+ * UBI wear-leveling unit.
+ *
+ * This unit is responsible for wear-leveling. It works in terms of physical
+ * eraseblocks and erase counters and knows nothing about logical eraseblocks,
+ * volumes, etc. From this unit's perspective all physical eraseblocks are of
+ * two types - used and free. Used physical eraseblocks are those that were
+ * "get" by the 'ubi_wl_get_peb()' function, and free physical eraseblocks are
+ * those that were put by the 'ubi_wl_put_peb()' function.
+ *
+ * Physical eraseblocks returned by 'ubi_wl_get_peb()' have only erase counter
+ * header. The rest of the physical eraseblock contains only 0xFF bytes.
+ *
+ * When physical eraseblocks are returned to the WL unit by means of the
+ * 'ubi_wl_put_peb()' function, they are scheduled for erasure. The erasure is
+ * done asynchronously in context of the per-UBI device background thread,
+ * which is also managed by the WL unit.
+ *
+ * The wear-leveling is ensured by means of moving the contents of used
+ * physical eraseblocks with low erase counter to free physical eraseblocks
+ * with high erase counter.
+ *
+ * The 'ubi_wl_get_peb()' function accepts data type hints which help to pick
+ * an "optimal" physical eraseblock. For example, when it is known that the
+ * physical eraseblock will be "put" soon because it contains short-term data,
+ * the WL unit may pick a free physical eraseblock with low erase counter, and
+ * so forth.
+ *
+ * If the WL unit fails to erase a physical eraseblock, it marks it as bad.
+ *
+ * This unit is also responsible for scrubbing. If a bit-flip is detected in a
+ * physical eraseblock, it has to be moved. Technically this is the same as
+ * moving it for wear-leveling reasons.
+ *
+ * As it was said, for the UBI unit all physical eraseblocks are either "free"
+ * or "used". Free eraseblock are kept in the @wl->free RB-tree, while used
+ * eraseblocks are kept in a set of different RB-trees: @wl->used,
+ * @wl->prot.pnum, @wl->prot.aec, and @wl->scrub.
+ *
+ * Note, in this implementation, we keep a small in-RAM object for each physical
+ * eraseblock. This is surely not a scalable solution. But it appears to be good
+ * enough for moderately large flashes and it is simple. In future, one may
+ * re-work this unit and make it more scalable.
+ *
+ * At the moment this unit does not utilize the sequence number, which was
+ * introduced relatively recently. But it would be wise to do this because the
+ * sequence number of a logical eraseblock characterizes how old is it. For
+ * example, when we move a PEB with low erase counter, and we need to pick the
+ * target PEB, we pick a PEB with the highest EC if our PEB is "old" and we
+ * pick target PEB with an average EC if our PEB is not very "old". This is a
+ * room for future re-works of the WL unit.
+ *
+ * FIXME: looks too complex, should be simplified (later).
+ */
+
+#include <linux/slab.h>
+#include <linux/crc32.h>
+#include <linux/freezer.h>
+#include <linux/kthread.h>
+#include "ubi.h"
+
+/* Number of physical eraseblocks reserved for wear-leveling purposes */
+#define WL_RESERVED_PEBS 1
+
+/*
+ * How many erase cycles are short term, unknown, and long term physical
+ * eraseblocks protected.
+ */
+#define ST_PROTECTION 16
+#define U_PROTECTION 10
+#define LT_PROTECTION 4
+
+/*
+ * Maximum difference between two erase counters. If this threshold is
+ * exceeded, the WL unit starts moving data from used physical eraseblocks with
+ * low erase counter to free physical eraseblocks with high erase counter.
+ */
+#define UBI_WL_THRESHOLD CONFIG_MTD_UBI_WL_THRESHOLD
+
+/*
+ * When a physical eraseblock is moved, the WL unit has to pick the target
+ * physical eraseblock to move to. The simplest way would be just to pick the
+ * one with the highest erase counter. But in certain workloads this could lead
+ * to an unlimited wear of one or few physical eraseblock. Indeed, imagine a
+ * situation when the picked physical eraseblock is constantly erased after the
+ * data is written to it. So, we have a constant which limits the highest erase
+ * counter of the free physical eraseblock to pick. Namely, the WL unit does
+ * not pick eraseblocks with erase counter greater then the lowest erase
+ * counter plus %WL_FREE_MAX_DIFF.
+ */
+#define WL_FREE_MAX_DIFF (2*UBI_WL_THRESHOLD)
+
+/*
+ * Maximum number of consecutive background thread failures which is enough to
+ * switch to read-only mode.
+ */
+#define WL_MAX_FAILURES 32
+
+/**
+ * struct ubi_wl_entry - wear-leveling entry.
+ * @rb: link in the corresponding RB-tree
+ * @ec: erase counter
+ * @pnum: physical eraseblock number
+ *
+ * Each physical eraseblock has a corresponding &struct wl_entry object which
+ * may be kept in different RB-trees.
+ */
+struct ubi_wl_entry {
+ struct rb_node rb;
+ int ec;
+ int pnum;
+};
+
+/**
+ * struct ubi_wl_prot_entry - PEB protection entry.
+ * @rb_pnum: link in the @wl->prot.pnum RB-tree
+ * @rb_aec: link in the @wl->prot.aec RB-tree
+ * @abs_ec: the absolute erase counter value when the protection ends
+ * @e: the wear-leveling entry of the physical eraseblock under protection
+ *
+ * When the WL unit returns a physical eraseblock, the physical eraseblock is
+ * protected from being moved for some "time". For this reason, the physical
+ * eraseblock is not directly moved from the @wl->free tree to the @wl->used
+ * tree. There is one more tree in between where this physical eraseblock is
+ * temporarily stored (@wl->prot).
+ *
+ * All this protection stuff is needed because:
+ * o we don't want to move physical eraseblocks just after we have given them
+ * to the user; instead, we first want to let users fill them up with data;
+ *
+ * o there is a chance that the user will put the physical eraseblock very
+ * soon, so it makes sense not to move it for some time, but wait; this is
+ * especially important in case of "short term" physical eraseblocks.
+ *
+ * Physical eraseblocks stay protected only for limited time. But the "time" is
+ * measured in erase cycles in this case. This is implemented with help of the
+ * absolute erase counter (@wl->abs_ec). When it reaches certain value, the
+ * physical eraseblocks are moved from the protection trees (@wl->prot.*) to
+ * the @wl->used tree.
+ *
+ * Protected physical eraseblocks are searched by physical eraseblock number
+ * (when they are put) and by the absolute erase counter (to check if it is
+ * time to move them to the @wl->used tree). So there are actually 2 RB-trees
+ * storing the protected physical eraseblocks: @wl->prot.pnum and
+ * @wl->prot.aec. They are referred to as the "protection" trees. The
+ * first one is indexed by the physical eraseblock number. The second one is
+ * indexed by the absolute erase counter. Both trees store
+ * &struct ubi_wl_prot_entry objects.
+ *
+ * Each physical eraseblock has 2 main states: free and used. The former state
+ * corresponds to the @wl->free tree. The latter state is split up on several
+ * sub-states:
+ * o the WL movement is allowed (@wl->used tree);
+ * o the WL movement is temporarily prohibited (@wl->prot.pnum and
+ * @wl->prot.aec trees);
+ * o scrubbing is needed (@wl->scrub tree).
+ *
+ * Depending on the sub-state, wear-leveling entries of the used physical
+ * eraseblocks may be kept in one of those trees.
+ */
+struct ubi_wl_prot_entry {
+ struct rb_node rb_pnum;
+ struct rb_node rb_aec;
+ unsigned long long abs_ec;
+ struct ubi_wl_entry *e;
+};
+
+/**
+ * struct ubi_work - UBI work description data structure.
+ * @list: a link in the list of pending works
+ * @func: worker function
+ * @priv: private data of the worker function
+ *
+ * @e: physical eraseblock to erase
+ * @torture: if the physical eraseblock has to be tortured
+ *
+ * The @func pointer points to the worker function. If the @cancel argument is
+ * not zero, the worker has to free the resources and exit immediately. The
+ * worker has to return zero in case of success and a negative error code in
+ * case of failure.
+ */
+struct ubi_work {
+ struct list_head list;
+ int (*func)(struct ubi_device *ubi, struct ubi_work *wrk, int cancel);
+ /* The below fields are only relevant to erasure works */
+ struct ubi_wl_entry *e;
+ int torture;
+};
+
+#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
+static int paranoid_check_ec(const struct ubi_device *ubi, int pnum, int ec);
+static int paranoid_check_in_wl_tree(struct ubi_wl_entry *e,
+ struct rb_root *root);
+#else
+#define paranoid_check_ec(ubi, pnum, ec) 0
+#define paranoid_check_in_wl_tree(e, root)
+#endif
+
+/* Slab cache for wear-leveling entries */
+static struct kmem_cache *wl_entries_slab;
+
+/**
+ * tree_empty - a helper function to check if an RB-tree is empty.
+ * @root: the root of the tree
+ *
+ * This function returns non-zero if the RB-tree is empty and zero if not.
+ */
+static inline int tree_empty(struct rb_root *root)
+{
+ return root->rb_node == NULL;
+}
+
+/**
+ * wl_tree_add - add a wear-leveling entry to a WL RB-tree.
+ * @e: the wear-leveling entry to add
+ * @root: the root of the tree
+ *
+ * Note, we use (erase counter, physical eraseblock number) pairs as keys in
+ * the @ubi->used and @ubi->free RB-trees.
+ */
+static void wl_tree_add(struct ubi_wl_entry *e, struct rb_root *root)
+{
+ struct rb_node **p, *parent = NULL;
+
+ p = &root->rb_node;
+ while (*p) {
+ struct ubi_wl_entry *e1;
+
+ parent = *p;
+ e1 = rb_entry(parent, struct ubi_wl_entry, rb);
+
+ if (e->ec < e1->ec)
+ p = &(*p)->rb_left;
+ else if (e->ec > e1->ec)
+ p = &(*p)->rb_right;
+ else {
+ ubi_assert(e->pnum != e1->pnum);
+ if (e->pnum < e1->pnum)
+ p = &(*p)->rb_left;
+ else
+ p = &(*p)->rb_right;
+ }
+ }
+
+ rb_link_node(&e->rb, parent, p);
+ rb_insert_color(&e->rb, root);
+}
+
+
+/*
+ * Helper functions to add and delete wear-leveling entries from different
+ * trees.
+ */
+
+static void free_tree_add(struct ubi_device *ubi, struct ubi_wl_entry *e)
+{
+ wl_tree_add(e, &ubi->free);
+}
+static inline void used_tree_add(struct ubi_device *ubi,
+ struct ubi_wl_entry *e)
+{
+ wl_tree_add(e, &ubi->used);
+}
+static inline void scrub_tree_add(struct ubi_device *ubi,
+ struct ubi_wl_entry *e)
+{
+ wl_tree_add(e, &ubi->scrub);
+}
+static inline void free_tree_del(struct ubi_device *ubi,
+ struct ubi_wl_entry *e)
+{
+ paranoid_check_in_wl_tree(e, &ubi->free);
+ rb_erase(&e->rb, &ubi->free);
+}
+static inline void used_tree_del(struct ubi_device *ubi,
+ struct ubi_wl_entry *e)
+{
+ paranoid_check_in_wl_tree(e, &ubi->used);
+ rb_erase(&e->rb, &ubi->used);
+}
+static inline void scrub_tree_del(struct ubi_device *ubi,
+ struct ubi_wl_entry *e)
+{
+ paranoid_check_in_wl_tree(e, &ubi->scrub);
+ rb_erase(&e->rb, &ubi->scrub);
+}
+
+/**
+ * do_work - do one pending work.
+ * @ubi: UBI device description object
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int do_work(struct ubi_device *ubi)
+{
+ int err;
+ struct ubi_work *wrk;
+
+ spin_lock(&ubi->wl_lock);
+
+ if (list_empty(&ubi->works)) {
+ spin_unlock(&ubi->wl_lock);
+ return 0;
+ }
+
+ wrk = list_entry(ubi->works.next, struct ubi_work, list);
+ list_del(&wrk->list);
+ spin_unlock(&ubi->wl_lock);
+
+ /*
+ * Call the worker function. Do not touch the work structure
+ * after this call as it will have been freed or reused by that
+ * time by the worker function.
+ */
+ err = wrk->func(ubi, wrk, 0);
+ if (unlikely(err))
+ ubi_err("work failed with error code %d", err);
+
+ spin_lock(&ubi->wl_lock);
+ ubi->works_count -= 1;
+ ubi_assert(ubi->works_count >= 0);
+ spin_unlock(&ubi->wl_lock);
+ return err;
+}
+
+/**
+ * produce_free_peb - produce a free physical eraseblock.
+ * @ubi: UBI device description object
+ *
+ * This function tries to make a free PEB by means of synchronous execution of
+ * pending works. This may be needed if, for example the background thread is
+ * disabled. Returns zero in case of success and a negative error code in case
+ * of failure.
+ */
+static int produce_free_peb(struct ubi_device *ubi)
+{
+ int err;
+
+ spin_lock(&ubi->wl_lock);
+ while (tree_empty(&ubi->free)) {
+ spin_unlock(&ubi->wl_lock);
+
+ dbg_wl("do one work synchronously");
+ err = do_work(ubi);
+ if (unlikely(err))
+ return err;
+
+ spin_lock(&ubi->wl_lock);
+ }
+ spin_unlock(&ubi->wl_lock);
+
+ return 0;
+}
+
+/**
+ * in_wl_tree - check if wear-leveling entry is present in a WL RB-tree.
+ * @e: the wear-leveling entry to check
+ * @root: the root of the tree
+ *
+ * This function returns non-zero if @e is in the @root RB-tree and zero if it
+ * is not.
+ */
+static int in_wl_tree(struct ubi_wl_entry *e, struct rb_root *root)
+{
+ struct rb_node *p;
+
+ p = root->rb_node;
+ while (p) {
+ struct ubi_wl_entry *e1;
+
+ e1 = rb_entry(p, struct ubi_wl_entry, rb);
+
+ if (e->pnum == e1->pnum) {
+ ubi_assert(e == e1);
+ return 1;
+ }
+
+ if (e->ec < e1->ec)
+ p = p->rb_left;
+ else if (e->ec > e1->ec)
+ p = p->rb_right;
+ else {
+ ubi_assert(e->pnum != e1->pnum);
+ if (e->pnum < e1->pnum)
+ p = p->rb_left;
+ else
+ p = p->rb_right;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * prot_tree_add - add physical eraseblock to protection trees.
+ * @ubi: UBI device description object
+ * @e: the physical eraseblock to add
+ * @pe: protection entry object to use
+ * @abs_ec: absolute erase counter value when this physical eraseblock has
+ * to be removed from the protection trees.
+ *
+ * @wl->lock has to be locked.
+ */
+static void prot_tree_add(struct ubi_device *ubi, struct ubi_wl_entry *e,
+ struct ubi_wl_prot_entry *pe, int abs_ec)
+{
+ struct rb_node **p, *parent = NULL;
+ struct ubi_wl_prot_entry *pe1;
+
+ pe->e = e;
+ pe->abs_ec = ubi->abs_ec + abs_ec;
+
+ p = &ubi->prot.pnum.rb_node;
+ while (*p) {
+ parent = *p;
+ pe1 = rb_entry(parent, struct ubi_wl_prot_entry, rb_pnum);
+
+ if (e->pnum < pe1->e->pnum)
+ p = &(*p)->rb_left;
+ else
+ p = &(*p)->rb_right;
+ }
+ rb_link_node(&pe->rb_pnum, parent, p);
+ rb_insert_color(&pe->rb_pnum, &ubi->prot.pnum);
+
+ p = &ubi->prot.aec.rb_node;
+ parent = NULL;
+ while (*p) {
+ parent = *p;
+ pe1 = rb_entry(parent, struct ubi_wl_prot_entry, rb_aec);
+
+ if (pe->abs_ec < pe1->abs_ec)
+ p = &(*p)->rb_left;
+ else
+ p = &(*p)->rb_right;
+ }
+ rb_link_node(&pe->rb_aec, parent, p);
+ rb_insert_color(&pe->rb_aec, &ubi->prot.aec);
+}
+
+/**
+ * find_wl_entry - find wear-leveling entry closest to certain erase counter.
+ * @root: the RB-tree where to look for
+ * @max: highest possible erase counter
+ *
+ * This function looks for a wear leveling entry with erase counter closest to
+ * @max and less then @max.
+ */
+static struct ubi_wl_entry *find_wl_entry(struct rb_root *root, int max)
+{
+ struct rb_node *p;
+ struct ubi_wl_entry *e;
+
+ e = rb_entry(rb_first(root), struct ubi_wl_entry, rb);
+ max += e->ec;
+
+ p = root->rb_node;
+ while (p) {
+ struct ubi_wl_entry *e1;
+
+ e1 = rb_entry(p, struct ubi_wl_entry, rb);
+ if (e1->ec >= max)
+ p = p->rb_left;
+ else {
+ p = p->rb_right;
+ e = e1;
+ }
+ }
+
+ return e;
+}
+
+/**
+ * pick_unknown - select an "unknown" physical eraseblock.
+ * @ubi: UBI device description object
+ *
+ * This function returns a physical eraseblock for "unknown" data. The wl->lock
+ * must be locked. The @wl->free list must not be empty.
+ */
+static struct ubi_wl_entry *pick_unknown(struct ubi_device *ubi)
+{
+ int medium_ec;
+ struct rb_node *p;
+ struct ubi_wl_entry *first, *last, *e;
+
+ /*
+ * For unknown data we are trying to pick a physical eraseblock with
+ * medium erase counter. But we by no means can pick a physical
+ * eraseblock with erase counter greater or equivalent then the the
+ * lowest erase counter plus %WL_FREE_MAX_DIFF.
+ */
+
+ first = rb_entry(rb_first(&ubi->free), struct ubi_wl_entry, rb);
+ last = rb_entry(rb_last(&ubi->free), struct ubi_wl_entry, rb);
+
+ if (last->ec - first->ec < WL_FREE_MAX_DIFF)
+ return rb_entry(ubi->free.rb_node, struct ubi_wl_entry, rb);
+
+ medium_ec = (first->ec + WL_FREE_MAX_DIFF)/2;
+ e = first;
+
+ p = ubi->free.rb_node;
+ while (p) {
+ struct ubi_wl_entry *e1;
+
+ e1 = rb_entry(p, struct ubi_wl_entry, rb);
+ if (e1->ec >= medium_ec)
+ p = p->rb_left;
+ else {
+ p = p->rb_right;
+ e = e1;
+ }
+ }
+
+ return e;
+}
+
+/**
+ * ubi_wl_get_peb - get a physical eraseblock.
+ * @ubi: UBI device description object
+ * @dtype: type of data which will be stored in this physical eraseblock
+ *
+ * This function returns a physical eraseblock in case of success and a
+ * negative error code in case of failure. Might sleep.
+ */
+int ubi_wl_get_peb(struct ubi_device *ubi, enum ubi_data_type dtype)
+{
+ int err, protect;
+ struct ubi_wl_entry *e;
+ struct ubi_wl_prot_entry *pe;
+
+ ubi_assert(dtype == UBI_DATA_LONGTERM || dtype == UBI_DATA_SHORTTERM ||
+ dtype == UBI_DATA_UNKNOWN);
+
+ pe = kmalloc(sizeof(struct ubi_wl_prot_entry), GFP_KERNEL);
+ if (unlikely(!pe))
+ return -ENOMEM;
+
+retry:
+ spin_lock(&ubi->wl_lock);
+ if (unlikely(tree_empty(&ubi->free))) {
+ if (unlikely(ubi->works_count == 0)) {
+ ubi_assert(list_empty(&ubi->works));
+ ubi_err("no free eraseblocks");
+ spin_unlock(&ubi->wl_lock);
+ kfree(pe);
+ return -ENOSPC;
+ }
+ spin_unlock(&ubi->wl_lock);
+
+ err = produce_free_peb(ubi);
+ if (unlikely(err < 0)) {
+ kfree(pe);
+ return err;
+ }
+ goto retry;
+ }
+
+ switch (dtype) {
+ case UBI_DATA_LONGTERM:
+ /*
+ * For long term data we pick a physical eraseblock
+ * with high erase counter. But the highest erase
+ * counter we can pick is bounded by the the lowest
+ * erase counter plus %WL_FREE_MAX_DIFF.
+ */
+ e = find_wl_entry(&ubi->free, WL_FREE_MAX_DIFF);
+ protect = LT_PROTECTION;
+ break;
+ case UBI_DATA_UNKNOWN:
+ e = pick_unknown(ubi);
+ protect = U_PROTECTION;
+ break;
+ case UBI_DATA_SHORTTERM:
+ /*
+ * For short term data we pick a physical eraseblock
+ * with the lowest erase counter as we expect it will
+ * be erased soon.
+ */
+ e = rb_entry(rb_first(&ubi->free),
+ struct ubi_wl_entry, rb);
+ protect = ST_PROTECTION;
+ break;
+ default:
+ protect = 0;
+ e = NULL;
+ BUG();
+ }
+
+ /*
+ * Move the physical eraseblock to the protection trees where it will
+ * be protected from being moved for some time.
+ */
+ free_tree_del(ubi, e);
+ prot_tree_add(ubi, e, pe, protect);
+
+ dbg_wl("PEB %d EC %d, protection %d", e->pnum, e->ec, protect);
+ spin_unlock(&ubi->wl_lock);
+
+ return e->pnum;
+}
+
+/**
+ * prot_tree_del - remove a physical eraseblock from the protection trees
+ * @ubi: UBI device description object
+ * @pnum: the physical eraseblock to remove
+ */
+static void prot_tree_del(struct ubi_device *ubi, int pnum)
+{
+ struct rb_node *p;
+ struct ubi_wl_prot_entry *pe = NULL;
+
+ p = ubi->prot.pnum.rb_node;
+ while (p) {
+
+ pe = rb_entry(p, struct ubi_wl_prot_entry, rb_pnum);
+
+ if (pnum == pe->e->pnum)
+ break;
+
+ if (pnum < pe->e->pnum)
+ p = p->rb_left;
+ else
+ p = p->rb_right;
+ }
+
+ ubi_assert(pe->e->pnum == pnum);
+ rb_erase(&pe->rb_aec, &ubi->prot.aec);
+ rb_erase(&pe->rb_pnum, &ubi->prot.pnum);
+ kfree(pe);
+}
+
+/**
+ * sync_erase - synchronously erase a physical eraseblock.
+ * @ubi: UBI device description object
+ * @e: the the physical eraseblock to erase
+ * @torture: if the physical eraseblock has to be tortured
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int sync_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, int torture)
+{
+ int err;
+ struct ubi_ec_hdr *ec_hdr;
+ unsigned long long ec = e->ec;
+
+ dbg_wl("erase PEB %d, old EC %llu", e->pnum, ec);
+
+ err = paranoid_check_ec(ubi, e->pnum, e->ec);
+ if (unlikely(err > 0))
+ return -EINVAL;
+
+ ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
+ if (unlikely(!ec_hdr))
+ return -ENOMEM;
+
+ err = ubi_io_sync_erase(ubi, e->pnum, torture);
+ if (unlikely(err < 0))
+ goto out_free;
+
+ ec += err;
+ if (unlikely(ec > UBI_MAX_ERASECOUNTER)) {
+ /*
+ * Erase counter overflow. Upgrade UBI and use 64-bit
+ * erase counters internally.
+ */
+ ubi_err("erase counter overflow at PEB %d, EC %llu",
+ e->pnum, ec);
+ err = -EINVAL;
+ goto out_free;
+ }
+
+ dbg_wl("erased PEB %d, new EC %llu", e->pnum, ec);
+
+ ec_hdr->ec = cpu_to_ubi64(ec);
+
+ err = ubi_io_write_ec_hdr(ubi, e->pnum, ec_hdr);
+ if (unlikely(err))
+ goto out_free;
+
+ e->ec = ec;
+ spin_lock(&ubi->wl_lock);
+ if (e->ec > ubi->max_ec)
+ ubi->max_ec = e->ec;
+ spin_unlock(&ubi->wl_lock);
+
+out_free:
+ kfree(ec_hdr);
+ return err;
+}
+
+/**
+ * check_protection_over - check if it is time to stop protecting some
+ * physical eraseblocks.
+ * @ubi: UBI device description object
+ *
+ * This function is called after each erase operation, when the absolute erase
+ * counter is incremented, to check if some physical eraseblock have not to be
+ * protected any longer. These physical eraseblocks are moved from the
+ * protection trees to the used tree.
+ */
+static void check_protection_over(struct ubi_device *ubi)
+{
+ struct ubi_wl_prot_entry *pe;
+
+ /*
+ * There may be several protected physical eraseblock to remove,
+ * process them all.
+ */
+ while (1) {
+ spin_lock(&ubi->wl_lock);
+ if (tree_empty(&ubi->prot.aec)) {
+ spin_unlock(&ubi->wl_lock);
+ break;
+ }
+
+ pe = rb_entry(rb_first(&ubi->prot.aec),
+ struct ubi_wl_prot_entry, rb_aec);
+
+ if (pe->abs_ec > ubi->abs_ec) {
+ spin_unlock(&ubi->wl_lock);
+ break;
+ }
+
+ dbg_wl("PEB %d protection over, abs_ec %llu, PEB abs_ec %llu",
+ pe->e->pnum, ubi->abs_ec, pe->abs_ec);
+ rb_erase(&pe->rb_aec, &ubi->prot.aec);
+ rb_erase(&pe->rb_pnum, &ubi->prot.pnum);
+ used_tree_add(ubi, pe->e);
+ spin_unlock(&ubi->wl_lock);
+
+ kfree(pe);
+ cond_resched();
+ }
+}
+
+/**
+ * schedule_ubi_work - schedule a work.
+ * @ubi: UBI device description object
+ * @wrk: the work to schedule
+ *
+ * This function enqueues a work defined by @wrk to the tail of the pending
+ * works list.
+ */
+static void schedule_ubi_work(struct ubi_device *ubi, struct ubi_work *wrk)
+{
+ spin_lock(&ubi->wl_lock);
+ list_add_tail(&wrk->list, &ubi->works);
+ ubi_assert(ubi->works_count >= 0);
+ ubi->works_count += 1;
+ if (ubi->thread_enabled)
+ wake_up_process(ubi->bgt_thread);
+ spin_unlock(&ubi->wl_lock);
+}
+
+static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk,
+ int cancel);
+
+/**
+ * schedule_erase - schedule an erase work.
+ * @ubi: UBI device description object
+ * @e: the WL entry of the physical eraseblock to erase
+ * @torture: if the physical eraseblock has to be tortured
+ *
+ * This function returns zero in case of success and a %-ENOMEM in case of
+ * failure.
+ */
+static int schedule_erase(struct ubi_device *ubi, struct ubi_wl_entry *e,
+ int torture)
+{
+ struct ubi_work *wl_wrk;
+
+ dbg_wl("schedule erasure of PEB %d, EC %d, torture %d",
+ e->pnum, e->ec, torture);
+
+ wl_wrk = kmalloc(sizeof(struct ubi_work), GFP_KERNEL);
+ if (unlikely(!wl_wrk))
+ return -ENOMEM;
+
+ wl_wrk->func = &erase_worker;
+ wl_wrk->e = e;
+ wl_wrk->torture = torture;
+
+ schedule_ubi_work(ubi, wl_wrk);
+ return 0;
+}
+
+/**
+ * wear_leveling_worker - wear-leveling worker function.
+ * @ubi: UBI device description object
+ * @wrk: the work object
+ * @cancel: non-zero if the worker has to free memory and exit
+ *
+ * This function copies a more worn out physical eraseblock to a less worn out
+ * one. Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int wear_leveling_worker(struct ubi_device *ubi, struct ubi_work *wrk,
+ int cancel)
+{
+ int err, put = 0;
+ struct ubi_wl_entry *e1, *e2;
+ struct ubi_vid_hdr *vid_hdr;
+
+ kfree(wrk);
+
+ if (unlikely(cancel))
+ return 0;
+
+ vid_hdr = ubi_zalloc_vid_hdr(ubi);
+ if (unlikely(!vid_hdr))
+ return -ENOMEM;
+
+ spin_lock(&ubi->wl_lock);
+
+ /*
+ * Only one WL worker at a time is supported at this implementation, so
+ * make sure a PEB is not being moved already.
+ */
+ if (ubi->move_to || tree_empty(&ubi->free) ||
+ (tree_empty(&ubi->used) && tree_empty(&ubi->scrub))) {
+ /*
+ * Only one WL worker at a time is supported at this
+ * implementation, so if a LEB is already being moved, cancel.
+ *
+ * No free physical eraseblocks? Well, we cancel wear-leveling
+ * then. It will be triggered again when a free physical
+ * eraseblock appears.
+ *
+ * No used physical eraseblocks? They must be temporarily
+ * protected from being moved. They will be moved to the
+ * @ubi->used tree later and the wear-leveling will be
+ * triggered again.
+ */
+ dbg_wl("cancel WL, a list is empty: free %d, used %d",
+ tree_empty(&ubi->free), tree_empty(&ubi->used));
+ ubi->wl_scheduled = 0;
+ spin_unlock(&ubi->wl_lock);
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return 0;
+ }
+
+ if (tree_empty(&ubi->scrub)) {
+ /*
+ * Now pick the least worn-out used physical eraseblock and a
+ * highly worn-out free physical eraseblock. If the erase
+ * counters differ much enough, start wear-leveling.
+ */
+ e1 = rb_entry(rb_first(&ubi->used), struct ubi_wl_entry, rb);
+ e2 = find_wl_entry(&ubi->free, WL_FREE_MAX_DIFF);
+
+ if (!(e2->ec - e1->ec >= UBI_WL_THRESHOLD)) {
+ dbg_wl("no WL needed: min used EC %d, max free EC %d",
+ e1->ec, e2->ec);
+ ubi->wl_scheduled = 0;
+ spin_unlock(&ubi->wl_lock);
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return 0;
+ }
+ used_tree_del(ubi, e1);
+ dbg_wl("move PEB %d EC %d to PEB %d EC %d",
+ e1->pnum, e1->ec, e2->pnum, e2->ec);
+ } else {
+ e1 = rb_entry(rb_first(&ubi->scrub), struct ubi_wl_entry, rb);
+ e2 = find_wl_entry(&ubi->free, WL_FREE_MAX_DIFF);
+ scrub_tree_del(ubi, e1);
+ dbg_wl("scrub PEB %d to PEB %d", e1->pnum, e2->pnum);
+ }
+
+ free_tree_del(ubi, e2);
+ ubi_assert(!ubi->move_from && !ubi->move_to);
+ ubi_assert(!ubi->move_to_put && !ubi->move_from_put);
+ ubi->move_from = e1;
+ ubi->move_to = e2;
+ spin_unlock(&ubi->wl_lock);
+
+ /*
+ * Now we are going to copy physical eraseblock @e1->pnum to @e2->pnum.
+ * We so far do not know which logical eraseblock our physical
+ * eraseblock (@e1) belongs to. We have to read the volume identifier
+ * header first.
+ */
+
+ err = ubi_io_read_vid_hdr(ubi, e1->pnum, vid_hdr, 0);
+ if (unlikely(err && err != UBI_IO_BITFLIPS)) {
+ if (err == UBI_IO_PEB_FREE) {
+ /*
+ * We are trying to move PEB without a VID header. UBI
+ * always write VID headers shortly after the PEB was
+ * given, so we have a situation when it did not have
+ * chance to write it down because it was preempted.
+ * Just re-schedule the work, so that next time it will
+ * likely have the VID header in place.
+ */
+ dbg_wl("PEB %d has no VID header", e1->pnum);
+ err = 0;
+ } else {
+ ubi_err("error %d while reading VID header from PEB %d",
+ err, e1->pnum);
+ if (err > 0)
+ err = -EIO;
+ }
+ goto error;
+ }
+
+ err = ubi_eba_copy_leb(ubi, e1->pnum, e2->pnum, vid_hdr);
+ if (unlikely(err)) {
+ if (err == UBI_IO_BITFLIPS)
+ err = 0;
+ goto error;
+ }
+
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ spin_lock(&ubi->wl_lock);
+ if (unlikely(!ubi->move_to_put))
+ used_tree_add(ubi, e2);
+ else
+ put = 1;
+ ubi->move_from = ubi->move_to = NULL;
+ ubi->move_from_put = ubi->move_to_put = 0;
+ ubi->wl_scheduled = 0;
+ spin_unlock(&ubi->wl_lock);
+
+ if (unlikely(put)) {
+ /*
+ * Well, the target PEB was put meanwhile, schedule it for
+ * erasure.
+ */
+ dbg_wl("PEB %d was put meanwhile, erase", e2->pnum);
+ err = schedule_erase(ubi, e2, 0);
+ if (unlikely(err)) {
+ kmem_cache_free(wl_entries_slab, e2);
+ ubi_ro_mode(ubi);
+ }
+ }
+
+ err = schedule_erase(ubi, e1, 0);
+ if (unlikely(err)) {
+ kmem_cache_free(wl_entries_slab, e1);
+ ubi_ro_mode(ubi);
+ }
+
+ dbg_wl("done");
+ return err;
+
+ /*
+ * Some error occurred. @e1 was not changed, so return it back. @e2
+ * might be changed, schedule it for erasure.
+ */
+error:
+ if (err)
+ dbg_wl("error %d occurred, cancel operation", err);
+ ubi_assert(err <= 0);
+
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ spin_lock(&ubi->wl_lock);
+ ubi->wl_scheduled = 0;
+ if (ubi->move_from_put)
+ put = 1;
+ else
+ used_tree_add(ubi, e1);
+ ubi->move_from = ubi->move_to = NULL;
+ ubi->move_from_put = ubi->move_to_put = 0;
+ spin_unlock(&ubi->wl_lock);
+
+ if (put) {
+ /*
+ * Well, the target PEB was put meanwhile, schedule it for
+ * erasure.
+ */
+ dbg_wl("PEB %d was put meanwhile, erase", e1->pnum);
+ err = schedule_erase(ubi, e1, 0);
+ if (unlikely(err)) {
+ kmem_cache_free(wl_entries_slab, e1);
+ ubi_ro_mode(ubi);
+ }
+ }
+
+ err = schedule_erase(ubi, e2, 0);
+ if (unlikely(err)) {
+ kmem_cache_free(wl_entries_slab, e2);
+ ubi_ro_mode(ubi);
+ }
+
+ yield();
+ return err;
+}
+
+/**
+ * ensure_wear_leveling - schedule wear-leveling if it is needed.
+ * @ubi: UBI device description object
+ *
+ * This function checks if it is time to start wear-leveling and schedules it
+ * if yes. This function returns zero in case of success and a negative error
+ * code in case of failure.
+ */
+static int ensure_wear_leveling(struct ubi_device *ubi)
+{
+ int err = 0;
+ struct ubi_wl_entry *e1;
+ struct ubi_wl_entry *e2;
+ struct ubi_work *wrk;
+
+ spin_lock(&ubi->wl_lock);
+ if (ubi->wl_scheduled)
+ /* Wear-leveling is already in the work queue */
+ goto out_unlock;
+
+ /*
+ * If the ubi->scrub tree is not empty, scrubbing is needed, and the
+ * the WL worker has to be scheduled anyway.
+ */
+ if (tree_empty(&ubi->scrub)) {
+ if (tree_empty(&ubi->used) || tree_empty(&ubi->free))
+ /* No physical eraseblocks - no deal */
+ goto out_unlock;
+
+ /*
+ * We schedule wear-leveling only if the difference between the
+ * lowest erase counter of used physical eraseblocks and a high
+ * erase counter of free physical eraseblocks is greater then
+ * %UBI_WL_THRESHOLD.
+ */
+ e1 = rb_entry(rb_first(&ubi->used), struct ubi_wl_entry, rb);
+ e2 = find_wl_entry(&ubi->free, WL_FREE_MAX_DIFF);
+
+ if (!(e2->ec - e1->ec >= UBI_WL_THRESHOLD))
+ goto out_unlock;
+ dbg_wl("schedule wear-leveling");
+ } else
+ dbg_wl("schedule scrubbing");
+
+ ubi->wl_scheduled = 1;
+ spin_unlock(&ubi->wl_lock);
+
+ wrk = kmalloc(sizeof(struct ubi_work), GFP_KERNEL);
+ if (unlikely(!wrk)) {
+ err = -ENOMEM;
+ goto out_cancel;
+ }
+
+ wrk->func = &wear_leveling_worker;
+ schedule_ubi_work(ubi, wrk);
+ return err;
+
+out_cancel:
+ spin_lock(&ubi->wl_lock);
+ ubi->wl_scheduled = 0;
+out_unlock:
+ spin_unlock(&ubi->wl_lock);
+ return err;
+}
+
+/**
+ * erase_worker - physical eraseblock erase worker function.
+ * @ubi: UBI device description object
+ * @wl_wrk: the work object
+ * @cancel: non-zero if the worker has to free memory and exit
+ *
+ * This function erases a physical eraseblock and perform torture testing if
+ * needed. It also takes care about marking the physical eraseblock bad if
+ * needed. Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk,
+ int cancel)
+{
+ int err;
+ struct ubi_wl_entry *e = wl_wrk->e;
+ int pnum = e->pnum;
+
+ if (unlikely(cancel)) {
+ dbg_wl("cancel erasure of PEB %d EC %d", pnum, e->ec);
+ kfree(wl_wrk);
+ kmem_cache_free(wl_entries_slab, e);
+ return 0;
+ }
+
+ dbg_wl("erase PEB %d EC %d", pnum, e->ec);
+
+ err = sync_erase(ubi, e, wl_wrk->torture);
+ if (likely(!err)) {
+ /* Fine, we've erased it successfully */
+ kfree(wl_wrk);
+
+ spin_lock(&ubi->wl_lock);
+ ubi->abs_ec += 1;
+ free_tree_add(ubi, e);
+ spin_unlock(&ubi->wl_lock);
+
+ /*
+ * One more erase operation has happened, take care about protected
+ * physical eraseblocks.
+ */
+ check_protection_over(ubi);
+
+ /* And take care about wear-leveling */
+ err = ensure_wear_leveling(ubi);
+ return err;
+ }
+
+ kfree(wl_wrk);
+ kmem_cache_free(wl_entries_slab, e);
+
+ if (err != -EIO) {
+ /*
+ * If this is not %-EIO, we have no idea what to do. Scheduling
+ * this physical eraseblock for erasure again would cause
+ * errors again and again. Well, lets switch to RO mode.
+ */
+ ubi_ro_mode(ubi);
+ return err;
+ }
+
+ /* It is %-EIO, the PEB went bad */
+
+ if (!ubi->bad_allowed) {
+ ubi_err("bad physical eraseblock %d detected", pnum);
+ ubi_ro_mode(ubi);
+ err = -EIO;
+ } else {
+ int need;
+
+ spin_lock(&ubi->volumes_lock);
+ need = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs + 1;
+ if (need > 0) {
+ need = ubi->avail_pebs >= need ? need : ubi->avail_pebs;
+ ubi->avail_pebs -= need;
+ ubi->rsvd_pebs += need;
+ ubi->beb_rsvd_pebs += need;
+ if (need > 0)
+ ubi_msg("reserve more %d PEBs", need);
+ }
+
+ if (ubi->beb_rsvd_pebs == 0) {
+ spin_unlock(&ubi->volumes_lock);
+ ubi_err("no reserved physical eraseblocks");
+ ubi_ro_mode(ubi);
+ return -EIO;
+ }
+
+ spin_unlock(&ubi->volumes_lock);
+ ubi_msg("mark PEB %d as bad", pnum);
+
+ err = ubi_io_mark_bad(ubi, pnum);
+ if (err) {
+ ubi_ro_mode(ubi);
+ return err;
+ }
+
+ spin_lock(&ubi->volumes_lock);
+ ubi->beb_rsvd_pebs -= 1;
+ ubi->bad_peb_count += 1;
+ ubi->good_peb_count -= 1;
+ ubi_calculate_reserved(ubi);
+ if (ubi->beb_rsvd_pebs == 0)
+ ubi_warn("last PEB from the reserved pool was used");
+ spin_unlock(&ubi->volumes_lock);
+ }
+
+ return err;
+}
+
+/**
+ * ubi_wl_put_peb - return a physical eraseblock to the wear-leveling
+ * unit.
+ * @ubi: UBI device description object
+ * @pnum: physical eraseblock to return
+ * @torture: if this physical eraseblock has to be tortured
+ *
+ * This function is called to return physical eraseblock @pnum to the pool of
+ * free physical eraseblocks. The @torture flag has to be set if an I/O error
+ * occurred to this @pnum and it has to be tested. This function returns zero
+ * in case of success and a negative error code in case of failure.
+ */
+int ubi_wl_put_peb(struct ubi_device *ubi, int pnum, int torture)
+{
+ int err;
+ struct ubi_wl_entry *e;
+
+ dbg_wl("PEB %d", pnum);
+ ubi_assert(pnum >= 0);
+ ubi_assert(pnum < ubi->peb_count);
+
+ spin_lock(&ubi->wl_lock);
+
+ e = ubi->lookuptbl[pnum];
+ if (unlikely(e == ubi->move_from)) {
+ /*
+ * User is putting the physical eraseblock which was selected to
+ * be moved. It will be scheduled for erasure in the
+ * wear-leveling worker.
+ */
+ dbg_wl("PEB %d is being moved", pnum);
+ ubi_assert(!ubi->move_from_put);
+ ubi->move_from_put = 1;
+ spin_unlock(&ubi->wl_lock);
+ return 0;
+ } else if (unlikely(e == ubi->move_to)) {
+ /*
+ * User is putting the physical eraseblock which was selected
+ * as the target the data is moved to. It may happen if the EBA
+ * unit already re-mapped the LEB but the WL unit did has not
+ * put the PEB to the "used" tree.
+ */
+ dbg_wl("PEB %d is the target of data moving", pnum);
+ ubi_assert(!ubi->move_to_put);
+ ubi->move_to_put = 1;
+ spin_unlock(&ubi->wl_lock);
+ return 0;
+ } else {
+ if (in_wl_tree(e, &ubi->used))
+ used_tree_del(ubi, e);
+ else if (unlikely(in_wl_tree(e, &ubi->scrub)))
+ scrub_tree_del(ubi, e);
+ else
+ prot_tree_del(ubi, e->pnum);
+ }
+ spin_unlock(&ubi->wl_lock);
+
+ err = schedule_erase(ubi, e, torture);
+ if (unlikely(err)) {
+ spin_lock(&ubi->wl_lock);
+ used_tree_add(ubi, e);
+ spin_unlock(&ubi->wl_lock);
+ }
+
+ return err;
+}
+
+/**
+ * ubi_wl_scrub_peb - schedule a physical eraseblock for scrubbing.
+ * @ubi: UBI device description object
+ * @pnum: the physical eraseblock to schedule
+ *
+ * If a bit-flip in a physical eraseblock is detected, this physical eraseblock
+ * needs scrubbing. This function schedules a physical eraseblock for
+ * scrubbing which is done in background. This function returns zero in case of
+ * success and a negative error code in case of failure.
+ */
+int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum)
+{
+ struct ubi_wl_entry *e;
+
+ ubi_msg("schedule PEB %d for scrubbing", pnum);
+
+retry:
+ spin_lock(&ubi->wl_lock);
+ e = ubi->lookuptbl[pnum];
+ if (unlikely(e == ubi->move_from) || in_wl_tree(e, &ubi->scrub)) {
+ spin_unlock(&ubi->wl_lock);
+ return 0;
+ }
+
+ if (unlikely(e == ubi->move_to)) {
+ /*
+ * This physical eraseblock was used to move data to. The data
+ * was moved but the PEB was not yet inserted to the proper
+ * tree. We should just wait a little and let the WL worker
+ * proceed.
+ */
+ spin_unlock(&ubi->wl_lock);
+ dbg_wl("the PEB %d is not in proper tree, retry", pnum);
+ yield();
+ goto retry;
+ }
+
+ if (in_wl_tree(e, &ubi->used))
+ used_tree_del(ubi, e);
+ else
+ prot_tree_del(ubi, pnum);
+
+ scrub_tree_add(ubi, e);
+ spin_unlock(&ubi->wl_lock);
+
+ /*
+ * Technically scrubbing is the same as wear-leveling, so it is done
+ * by the WL worker.
+ */
+ return ensure_wear_leveling(ubi);
+}
+
+/**
+ * ubi_wl_flush - flush all pending works.
+ * @ubi: UBI device description object
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+int ubi_wl_flush(struct ubi_device *ubi)
+{
+ int err, pending_count;
+
+ pending_count = ubi->works_count;
+
+ dbg_wl("flush (%d pending works)", pending_count);
+
+ /*
+ * Erase while the pending works queue is not empty, but not more then
+ * the number of currently pending works.
+ */
+ while (pending_count-- > 0) {
+ err = do_work(ubi);
+ if (unlikely(err))
+ return err;
+ }
+
+ return 0;
+}
+
+/**
+ * tree_destroy - destroy an RB-tree.
+ * @root: the root of the tree to destroy
+ */
+static void tree_destroy(struct rb_root *root)
+{
+ struct rb_node *rb;
+ struct ubi_wl_entry *e;
+
+ rb = root->rb_node;
+ while (rb) {
+ if (rb->rb_left)
+ rb = rb->rb_left;
+ else if (rb->rb_right)
+ rb = rb->rb_right;
+ else {
+ e = rb_entry(rb, struct ubi_wl_entry, rb);
+
+ rb = rb_parent(rb);
+ if (rb) {
+ if (rb->rb_left == &e->rb)
+ rb->rb_left = NULL;
+ else
+ rb->rb_right = NULL;
+ }
+
+ kmem_cache_free(wl_entries_slab, e);
+ }
+ }
+}
+
+/**
+ * ubi_thread - UBI background thread.
+ * @u: the UBI device description object pointer
+ */
+static int ubi_thread(void *u)
+{
+ int failures = 0;
+ struct ubi_device *ubi = u;
+
+ ubi_msg("background thread \"%s\" started, PID %d",
+ ubi->bgt_name, current->pid);
+
+ for (;;) {
+ int err;
+
+ if (kthread_should_stop())
+ goto out;
+
+ if (try_to_freeze())
+ continue;
+
+ spin_lock(&ubi->wl_lock);
+ if (list_empty(&ubi->works) || ubi->ro_mode ||
+ !ubi->thread_enabled) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ spin_unlock(&ubi->wl_lock);
+ schedule();
+ continue;
+ }
+ spin_unlock(&ubi->wl_lock);
+
+ err = do_work(ubi);
+ if (unlikely(err)) {
+ ubi_err("%s: work failed with error code %d",
+ ubi->bgt_name, err);
+ if (failures++ > WL_MAX_FAILURES) {
+ /*
+ * Too many failures, disable the thread and
+ * switch to read-only mode.
+ */
+ ubi_msg("%s: %d consecutive failures",
+ ubi->bgt_name, WL_MAX_FAILURES);
+ ubi_ro_mode(ubi);
+ break;
+ }
+ } else
+ failures = 0;
+
+ cond_resched();
+ }
+
+out:
+ dbg_wl("background thread \"%s\" is killed", ubi->bgt_name);
+ return 0;
+}
+
+/**
+ * cancel_pnding - cancel all pending works.
+ * @ubi: UBI device description object
+ */
+static void cancel_pnding(struct ubi_device *ubi)
+{
+ while (!list_empty(&ubi->works)) {
+ struct ubi_work *wrk;
+
+ wrk = list_entry(ubi->works.next, struct ubi_work, list);
+ list_del(&wrk->list);
+ wrk->func(ubi, wrk, 1);
+ ubi->works_count -= 1;
+ ubi_assert(ubi->works_count >= 0);
+ }
+}
+
+/**
+ * ubi_wl_init_scan - initialize the wear-leveling unit using scanning
+ * information.
+ * @ubi: UBI device description object
+ * @si: scanning information
+ *
+ * This function returns zero in case of success, and a negative error code in
+ * case of failure.
+ */
+int ubi_wl_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si)
+{
+ int err;
+ struct rb_node *rb1, *rb2;
+ struct ubi_scan_volume *sv;
+ struct ubi_scan_leb *seb, *tmp;
+ struct ubi_wl_entry *e;
+
+
+ ubi->used = ubi->free = ubi->scrub = RB_ROOT;
+ ubi->prot.pnum = ubi->prot.aec = RB_ROOT;
+ spin_lock_init(&ubi->wl_lock);
+ ubi->max_ec = si->max_ec;
+ INIT_LIST_HEAD(&ubi->works);
+
+ sprintf(ubi->bgt_name, UBI_BGT_NAME_PATTERN, ubi->ubi_num);
+
+ ubi->bgt_thread = kthread_create(ubi_thread, ubi, ubi->bgt_name);
+ if (IS_ERR(ubi->bgt_thread)) {
+ err = PTR_ERR(ubi->bgt_thread);
+ ubi_err("cannot spawn \"%s\", error %d", ubi->bgt_name,
+ err);
+ return err;
+ }
+
+ if (ubi_devices_cnt == 0) {
+ wl_entries_slab = kmem_cache_create("ubi_wl_entry_slab",
+ sizeof(struct ubi_wl_entry),
+ 0, 0, NULL, NULL);
+ if (!wl_entries_slab)
+ return -ENOMEM;
+ }
+
+ err = -ENOMEM;
+ ubi->lookuptbl = kzalloc(ubi->peb_count * sizeof(void *), GFP_KERNEL);
+ if (!ubi->lookuptbl)
+ goto out_free;
+
+ list_for_each_entry_safe(seb, tmp, &si->erase, u.list) {
+ cond_resched();
+
+ e = kmem_cache_alloc(wl_entries_slab, GFP_KERNEL);
+ if (unlikely(!e))
+ goto out_free;
+
+ e->pnum = seb->pnum;
+ e->ec = seb->ec;
+ ubi->lookuptbl[e->pnum] = e;
+ if (schedule_erase(ubi, e, 0)) {
+ kmem_cache_free(wl_entries_slab, e);
+ goto out_free;
+ }
+ }
+
+ list_for_each_entry(seb, &si->free, u.list) {
+ cond_resched();
+
+ e = kmem_cache_alloc(wl_entries_slab, GFP_KERNEL);
+ if (unlikely(!e))
+ goto out_free;
+
+ e->pnum = seb->pnum;
+ e->ec = seb->ec;
+ ubi_assert(e->ec >= 0);
+ free_tree_add(ubi, e);
+ ubi->lookuptbl[e->pnum] = e;
+ }
+
+ list_for_each_entry(seb, &si->corr, u.list) {
+ cond_resched();
+
+ e = kmem_cache_alloc(wl_entries_slab, GFP_KERNEL);
+ if (unlikely(!e))
+ goto out_free;
+
+ e->pnum = seb->pnum;
+ e->ec = seb->ec;
+ ubi->lookuptbl[e->pnum] = e;
+ if (schedule_erase(ubi, e, 0)) {
+ kmem_cache_free(wl_entries_slab, e);
+ goto out_free;
+ }
+ }
+
+ ubi_rb_for_each_entry(rb1, sv, &si->volumes, rb) {
+ ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb) {
+ cond_resched();
+
+ e = kmem_cache_alloc(wl_entries_slab, GFP_KERNEL);
+ if (unlikely(!e))
+ goto out_free;
+
+ e->pnum = seb->pnum;
+ e->ec = seb->ec;
+ ubi->lookuptbl[e->pnum] = e;
+ if (!seb->scrub) {
+ dbg_wl("add PEB %d EC %d to the used tree",
+ e->pnum, e->ec);
+ used_tree_add(ubi, e);
+ } else {
+ dbg_wl("add PEB %d EC %d to the scrub tree",
+ e->pnum, e->ec);
+ scrub_tree_add(ubi, e);
+ }
+ }
+ }
+
+ if (WL_RESERVED_PEBS > ubi->avail_pebs) {
+ ubi_err("no enough physical eraseblocks (%d, need %d)",
+ ubi->avail_pebs, WL_RESERVED_PEBS);
+ goto out_free;
+ }
+ ubi->avail_pebs -= WL_RESERVED_PEBS;
+ ubi->rsvd_pebs += WL_RESERVED_PEBS;
+
+ /* Schedule wear-leveling if needed */
+ err = ensure_wear_leveling(ubi);
+ if (err)
+ goto out_free;
+
+ return 0;
+
+out_free:
+ cancel_pnding(ubi);
+ tree_destroy(&ubi->used);
+ tree_destroy(&ubi->free);
+ tree_destroy(&ubi->scrub);
+ kfree(ubi->lookuptbl);
+ if (ubi_devices_cnt == 0)
+ kmem_cache_destroy(wl_entries_slab);
+ return err;
+}
+
+/**
+ * protection_trees_destroy - destroy the protection RB-trees.
+ * @ubi: UBI device description object
+ */
+static void protection_trees_destroy(struct ubi_device *ubi)
+{
+ struct rb_node *rb;
+ struct ubi_wl_prot_entry *pe;
+
+ rb = ubi->prot.aec.rb_node;
+ while (rb) {
+ if (rb->rb_left)
+ rb = rb->rb_left;
+ else if (rb->rb_right)
+ rb = rb->rb_right;
+ else {
+ pe = rb_entry(rb, struct ubi_wl_prot_entry, rb_aec);
+
+ rb = rb_parent(rb);
+ if (rb) {
+ if (rb->rb_left == &pe->rb_aec)
+ rb->rb_left = NULL;
+ else
+ rb->rb_right = NULL;
+ }
+
+ kmem_cache_free(wl_entries_slab, pe->e);
+ kfree(pe);
+ }
+ }
+}
+
+/**
+ * ubi_wl_close - close the wear-leveling unit.
+ * @ubi: UBI device description object
+ */
+void ubi_wl_close(struct ubi_device *ubi)
+{
+ dbg_wl("disable \"%s\"", ubi->bgt_name);
+ if (ubi->bgt_thread)
+ kthread_stop(ubi->bgt_thread);
+
+ dbg_wl("close the UBI wear-leveling unit");
+
+ cancel_pnding(ubi);
+ protection_trees_destroy(ubi);
+ tree_destroy(&ubi->used);
+ tree_destroy(&ubi->free);
+ tree_destroy(&ubi->scrub);
+ kfree(ubi->lookuptbl);
+ if (ubi_devices_cnt == 1)
+ kmem_cache_destroy(wl_entries_slab);
+}
+
+#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
+
+/**
+ * paranoid_check_ec - make sure that the erase counter of a physical eraseblock
+ * is correct.
+ * @ubi: UBI device description object
+ * @pnum: the physical eraseblock number to check
+ * @ec: the erase counter to check
+ *
+ * This function returns zero if the erase counter of physical eraseblock @pnum
+ * is equivalent to @ec, %1 if not, and a negative error code if an error
+ * occurred.
+ */
+static int paranoid_check_ec(const struct ubi_device *ubi, int pnum, int ec)
+{
+ int err;
+ long long read_ec;
+ struct ubi_ec_hdr *ec_hdr;
+
+ ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
+ if (unlikely(!ec_hdr))
+ return -ENOMEM;
+
+ err = ubi_io_read_ec_hdr(ubi, pnum, ec_hdr, 0);
+ if (unlikely(err) && err != UBI_IO_BITFLIPS) {
+ /* The header does not have to exist */
+ err = 0;
+ goto out_free;
+ }
+
+ read_ec = ubi64_to_cpu(ec_hdr->ec);
+ if (unlikely(ec != read_ec)) {
+ ubi_err("paranoid check failed for PEB %d", pnum);
+ ubi_err("read EC is %lld, should be %d", read_ec, ec);
+ ubi_dbg_dump_stack();
+ err = 1;
+ } else
+ err = 0;
+
+out_free:
+ kfree(ec_hdr);
+ return err;
+}
+
+/**
+ * paranoid_check_in_wl_tree - make sure that a wear-leveling entry is present
+ * in a WL RB-tree.
+ * @e: the wear-leveling entry to check
+ * @root: the root of the tree
+ *
+ * This function returns zero if @e is in the @root RB-tree and %1 if it
+ * is not.
+ */
+static int paranoid_check_in_wl_tree(struct ubi_wl_entry *e,
+ struct rb_root *root)
+{
+ if (likely(in_wl_tree(e, root)))
+ return 0;
+
+ ubi_err("paranoid check failed for PEB %d, EC %d, RB-tree %p ",
+ e->pnum, e->ec, root);
+ ubi_dbg_dump_stack();
+ return 1;
+}
+
+#endif /* CONFIG_MTD_UBI_DEBUG_PARANOID */
^ permalink raw reply [flat|nested] 22+ messages in thread* Re: [PATCH 09/20 take 4] UBI: wear-leveling unit
2007-03-23 16:43 ` [PATCH 09/20 take 4] UBI: wear-leveling unit Artem Bityutskiy
@ 2007-03-26 12:34 ` Frank Haverkamp
0 siblings, 0 replies; 22+ messages in thread
From: Frank Haverkamp @ 2007-03-26 12:34 UTC (permalink / raw)
To: Artem Bityutskiy
Cc: Linux Kernel Mailing List, David Woodhouse, Josh Boyer,
Alexander Schmidt
Hi,
I wonder if a generic wear-leveling infrastructure makes sense. Artem is
showing us here his example of how he is attacking the problem for UBI.
The wear-leveling described here is only one approach out of many
possible. A different one, I think, is used where e.g. filesystems do
their own approach, because they have deeper knowledge on how the blocks
are used.
I think this is something special and out of the scope of what I try to
point out here.
Artems approach for UBI, as far as I can see, uses currently the hints:
erase counts per block a sequence number and a full view of all existing
blocks. If a block is requested the user can give following information:
LONGTERM, UNKNOWN, and SHORTTERM. Internally it has trees containing:
free blocks, used blocks, and blocks to scrub.
Let me try to illustrate how I think that a generic aproach might look
like:
struct wlevel_block {
phys_block_num;
erase_count;
sequence_number;
... /* which other hints are reasonable?
maybe other devices -> other hints? */
};
struct wlevel {
int (* erase_block)(phys_num, priv_data); /* callback */
/* more callbacks needed? */
...
void *priv_data;
};
wlevel_init(struct wlevel *wl);
wlevel_add(struct wlevel *wl, struct block_info *bi); /* add block info
e.g. during scan */
wlevel_put(struct wlevel *wl, block); /* free/erase a block */
wlevel_scrub(struct wlevel *wl, block);
enum characteristics {
WL_DATA_LONGTERM,
WL_DATA_UNKNOWN,
WL_DATA_SHORTTERM,
};
wlevel_get(struct wlevel *wl, enum characteristics ch);
...
wlevel_destroy(struct wlevel *wl);
I do not hope that throwing this topic into the discussion might lead to
more itzi-bitsi-ness, and obsolete interfaces in the code (which were
just removed), but it might be worth a discussion on the side, to
explore if there are other people trying to solve similar problems like
we try here for the FLASH example, and if a common approach for this
problem makes sense or not - and of course if so how it could look like.
Regards,
Frank
^ permalink raw reply [flat|nested] 22+ messages in thread
* [PATCH 10/20 take 4] UBI: EBA unit
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (8 preceding siblings ...)
2007-03-23 16:43 ` [PATCH 09/20 take 4] UBI: wear-leveling unit Artem Bityutskiy
@ 2007-03-23 16:43 ` Artem Bityutskiy
2007-03-23 16:43 ` [PATCH 11/20 take 4] UBI: kernel API functions Artem Bityutskiy
` (9 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:43 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 31901 bytes --]
diff -auNrp tmp-from/drivers/mtd/ubi/eba.c tmp-to/drivers/mtd/ubi/eba.c
--- tmp-from/drivers/mtd/ubi/eba.c 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/eba.c 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,1132 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * The UBI Eraseblock Association (EBA) unit.
+ *
+ * This unit is responsible for I/O to/from logical eraseblock.
+ *
+ * Although in this implementation the EBA table is fully kept and managed in
+ * RAM, which assumes poor scalability, it might be (partially) maintained on
+ * flash in future implementations.
+ *
+ * The EBA unit implements per-logical eraseblock locking. Before accessing a
+ * logical eraseblock it is locked for reading or writing. The per-logical
+ * eraseblock locking is implemented by means of the lock tree. The lock tree
+ * is an RB-tree which refers all the currently locked logical eraseblocks. The
+ * lock tree elements are &struct ltree_entry objects. They are indexed by
+ * (@vol_id, @lnum) pairs.
+ *
+ * EBA also maintains the global sequence counter which is incremented each
+ * time a logical eraseblock is mapped to a physical eraseblock and it is
+ * stored in the volume identifier header. This means that each VID header has
+ * a unique sequence number. The sequence number is only increased an we assume
+ * 64 bits is enough to never overflow.
+ */
+
+#include <linux/slab.h>
+#include <linux/crc32.h>
+#include <linux/err.h>
+#include "ubi.h"
+
+/**
+ * struct ltree_entry - an entry in the lock tree.
+ * @rb: links RB-tree nodes
+ * @vol_id: volume ID of the locked logical eraseblock
+ * @lnum: locked logical eraseblock number
+ * @users: how many tasks are using this logical eraseblock or wait for it
+ * @mutex: read/write mutex to implement read/write access serialization to
+ * the (@vol_id, @lnum) logical eraseblock
+ *
+ * When a logical eraseblock is being locked - corresponding &struct ltree_entry
+ * object is inserted to the lock tree (@ubi->ltree).
+ */
+struct ltree_entry {
+ struct rb_node rb;
+ int vol_id;
+ int lnum;
+ int users;
+ struct rw_semaphore mutex;
+};
+
+/* Slab cache for lock-tree entries */
+static struct kmem_cache *ltree_slab;
+
+/**
+ * next_sqnum - get next sequence number.
+ * @ubi: UBI device description object
+ *
+ * This function returns next sequence number to use, which is just the current
+ * global sequence counter value. It also increases the global sequence
+ * counter.
+ */
+static unsigned long long next_sqnum(struct ubi_device *ubi)
+{
+ unsigned long long sqnum;
+
+ spin_lock(&ubi->ltree_lock);
+ sqnum = ubi->global_sqnum++;
+ spin_unlock(&ubi->ltree_lock);
+
+ return sqnum;
+}
+
+/**
+ * ubi_get_compat - get compatibility flags of a volume.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ *
+ * This function returns compatibility flags for an internal volume. User
+ * volumes have no compatibility flags, so %0 is returned.
+ */
+static int ubi_get_compat(const struct ubi_device *ubi, int vol_id)
+{
+ if (vol_id == UBI_LAYOUT_VOL_ID)
+ return UBI_LAYOUT_VOLUME_COMPAT;
+ return 0;
+}
+
+/**
+ * ltree_lookup - look up the lock tree.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ * @lnum: logical eraseblock number
+ *
+ * This function returns a pointer to the corresponding &struct ltree_entry
+ * object if the logical eraseblock is locked and %NULL if it is not.
+ * @ubi->ltree_lock has to be locked.
+ */
+static struct ltree_entry *ltree_lookup(struct ubi_device *ubi, int vol_id,
+ int lnum)
+{
+ struct rb_node *p;
+
+ p = ubi->ltree.rb_node;
+ while (p) {
+ struct ltree_entry *le;
+
+ le = rb_entry(p, struct ltree_entry, rb);
+
+ if (vol_id < le->vol_id)
+ p = p->rb_left;
+ else if (vol_id > le->vol_id)
+ p = p->rb_right;
+ else {
+ if (lnum < le->lnum)
+ p = p->rb_left;
+ else if (lnum > le->lnum)
+ p = p->rb_right;
+ else
+ return le;
+ }
+ }
+
+ return NULL;
+}
+
+/**
+ * ltree_add_entry - add new entry to the lock tree.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ * @lnum: logical eraseblock number
+ *
+ * This function adds new entry for logical eraseblock (@vol_id, @lnum) to the
+ * lock tree. If such entry is already there, its usage counter is increased.
+ * Returns pointer to the lock tree entry or %-ENOMEM if memory allocation
+ * failed.
+ */
+static struct ltree_entry *ltree_add_entry(struct ubi_device *ubi, int vol_id,
+ int lnum)
+{
+ struct ltree_entry *le, *le1, *le_free;
+
+ le = kmem_cache_alloc(ltree_slab, GFP_KERNEL);
+ if (unlikely(!le))
+ return ERR_PTR(-ENOMEM);
+
+ le->vol_id = vol_id;
+ le->lnum = lnum;
+
+ spin_lock(&ubi->ltree_lock);
+ le1 = ltree_lookup(ubi, vol_id, lnum);
+
+ if (le1) {
+ /*
+ * This logical eraseblock is already locked. The newly
+ * allocated lock entry is not needed.
+ */
+ le_free = le;
+ le = le1;
+ } else {
+ struct rb_node **p, *parent = NULL;
+
+ /*
+ * No lock entry, add the newly allocated one to the
+ * @ubi->ltree RB-tree.
+ */
+ le_free = NULL;
+
+ p = &ubi->ltree.rb_node;
+ while (*p) {
+ parent = *p;
+ le1 = rb_entry(parent, struct ltree_entry, rb);
+
+ if (vol_id < le1->vol_id)
+ p = &(*p)->rb_left;
+ else if (vol_id > le1->vol_id)
+ p = &(*p)->rb_right;
+ else {
+ ubi_assert(lnum != le1->lnum);
+ if (lnum < le1->lnum)
+ p = &(*p)->rb_left;
+ else
+ p = &(*p)->rb_right;
+ }
+ }
+
+ rb_link_node(&le->rb, parent, p);
+ rb_insert_color(&le->rb, &ubi->ltree);
+ }
+ le->users += 1;
+ spin_unlock(&ubi->ltree_lock);
+
+ if (le_free)
+ kmem_cache_free(ltree_slab, le_free);
+
+ return le;
+}
+
+/**
+ * leb_read_lock - lock logical eraseblock for reading.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ * @lnum: logical eraseblock number
+ *
+ * This function locks a logical eraseblock for reading. Returns zero in case
+ * of success and a negative error code in case of failure.
+ */
+static int leb_read_lock(struct ubi_device *ubi, int vol_id, int lnum)
+{
+ struct ltree_entry *le;
+
+ le = ltree_add_entry(ubi, vol_id, lnum);
+ if (unlikely(IS_ERR(le)))
+ return PTR_ERR(le);
+ down_read(&le->mutex);
+ return 0;
+}
+
+/**
+ * leb_read_unlock - unlock logical eraseblock.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ * @lnum: logical eraseblock number
+ */
+static void leb_read_unlock(struct ubi_device *ubi, int vol_id, int lnum)
+{
+ int free = 0;
+ struct ltree_entry *le;
+
+ spin_lock(&ubi->ltree_lock);
+ le = ltree_lookup(ubi, vol_id, lnum);
+ le->users -= 1;
+ ubi_assert(le->users >= 0);
+ if (le->users == 0) {
+ rb_erase(&le->rb, &ubi->ltree);
+ free = 1;
+ }
+ spin_unlock(&ubi->ltree_lock);
+
+ up_read(&le->mutex);
+ if (free)
+ kmem_cache_free(ltree_slab, le);
+}
+
+/**
+ * leb_write_lock - lock logical eraseblock for writing.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ * @lnum: logical eraseblock number
+ *
+ * This function locks a logical eraseblock for writing. Returns zero in case
+ * of success and a negative error code in case of failure.
+ */
+static int leb_write_lock(struct ubi_device *ubi, int vol_id, int lnum)
+{
+ struct ltree_entry *le;
+
+ le = ltree_add_entry(ubi, vol_id, lnum);
+ if (unlikely(IS_ERR(le)))
+ return PTR_ERR(le);
+ down_write(&le->mutex);
+ return 0;
+}
+
+/**
+ * leb_write_unlock - unlock logical eraseblock.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ * @lnum: logical eraseblock number
+ */
+static void leb_write_unlock(struct ubi_device *ubi, int vol_id, int lnum)
+{
+ int free;
+ struct ltree_entry *le;
+
+ spin_lock(&ubi->ltree_lock);
+ le = ltree_lookup(ubi, vol_id, lnum);
+ le->users -= 1;
+ ubi_assert(le->users >= 0);
+ if (le->users == 0) {
+ rb_erase(&le->rb, &ubi->ltree);
+ free = 1;
+ } else
+ free = 0;
+ spin_unlock(&ubi->ltree_lock);
+
+ up_write(&le->mutex);
+ if (free)
+ kmem_cache_free(ltree_slab, le);
+}
+
+/**
+ * ubi_eba_unmap_leb - un-map logical eraseblock.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ * @lnum: logical eraseblock number
+ *
+ * This function un-maps logical eraseblock @lnum and schedules corresponding
+ * physical eraseblock for erasure. Returns zero in case of success and a
+ * negative error code in case of failure.
+ */
+int ubi_eba_unmap_leb(struct ubi_device *ubi, int vol_id, int lnum)
+{
+ int idx = vol_id2idx(ubi, vol_id), err, pnum;
+ struct ubi_volume *vol = ubi->volumes[idx];
+
+ if (unlikely(ubi->ro_mode))
+ return -EROFS;
+
+ err = leb_write_lock(ubi, vol_id, lnum);
+ if (unlikely(err))
+ return err;
+
+ pnum = vol->eba_tbl[lnum];
+ if (pnum < 0)
+ /* This logical eraseblock is already unmapped */
+ goto out_unlock;
+
+ dbg_eba("erase LEB %d:%d, PEB %d", vol_id, lnum, pnum);
+
+ vol->eba_tbl[lnum] = UBI_LEB_UNMAPPED;
+ err = ubi_wl_put_peb(ubi, pnum, 0);
+
+out_unlock:
+ leb_write_unlock(ubi, vol_id, lnum);
+ return err;
+}
+
+/**
+ * ubi_eba_read_leb - read data.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ * @lnum: logical eraseblock number
+ * @buf: buffer to store the read data
+ * @offset: offset from where to read
+ * @len: how many bytes to read
+ * @check: data CRC check flag
+ *
+ * If the logical eraseblock @lnum is unmapped, @buf is filled with 0xFF
+ * bytes. The @check flag only makes sense for static volumes and forces
+ * eraseblock data CRC checking.
+ *
+ * In case of success this function returns zero. In case of a static volume,
+ * if data CRC mismatches - %-EBADMSG is returned. %-EBADMSG may also be
+ * returned for any volume type if an ECC error was detected by the MTD device
+ * driver. Other negative error cored may be returned in case of other errors.
+ */
+int ubi_eba_read_leb(struct ubi_device *ubi, int vol_id, int lnum, void *buf,
+ int offset, int len, int check)
+{
+ int err, pnum, scrub = 0, idx = vol_id2idx(ubi, vol_id);
+ struct ubi_vid_hdr *vid_hdr;
+ struct ubi_volume *vol = ubi->volumes[idx];
+ uint32_t crc, crc1;
+
+ err = leb_read_lock(ubi, vol_id, lnum);
+ if (unlikely(err))
+ return err;
+
+ pnum = vol->eba_tbl[lnum];
+ if (pnum < 0) {
+ /*
+ * The logical eraseblock is not mapped, fill the whole buffer
+ * with 0xFF bytes. The exception is static volumes for which
+ * it is an error to read unmapped logical eraseblocks.
+ */
+ dbg_eba("read %d bytes from offset %d of LEB %d:%d (unmapped)",
+ len, offset, vol_id, lnum);
+ leb_read_unlock(ubi, vol_id, lnum);
+ ubi_assert(vol->vol_type != UBI_STATIC_VOLUME);
+ memset(buf, 0xFF, len);
+ return 0;
+ }
+
+ dbg_eba("read %d bytes from offset %d of LEB %d:%d, PEB %d",
+ len, offset, vol_id, lnum, pnum);
+
+ if (vol->vol_type == UBI_DYNAMIC_VOLUME)
+ check = 0;
+
+retry:
+ if (check) {
+ vid_hdr = ubi_zalloc_vid_hdr(ubi);
+ if (unlikely(!vid_hdr)) {
+ err = -ENOMEM;
+ goto out_unlock;
+ }
+
+ err = ubi_io_read_vid_hdr(ubi, pnum, vid_hdr, 1);
+ if (unlikely(err) && err != UBI_IO_BITFLIPS) {
+ if (err > 0) {
+ /*
+ * The header is either absent or corrupted.
+ * The former case means there is a bug -
+ * switch to read-only mode just in case.
+ * The latter case means a real corruption - we
+ * may try to recover data. FIXME: but this is
+ * not implemented.
+ */
+ if (err == UBI_IO_BAD_VID_HDR) {
+ ubi_warn("bad VID header at PEB %d, LEB"
+ "%d:%d", pnum, vol_id, lnum);
+ err = -EBADMSG;
+ } else
+ ubi_ro_mode(ubi);
+ }
+ goto out_free;
+ } else if (unlikely(err == UBI_IO_BITFLIPS))
+ scrub = 1;
+
+ ubi_assert(lnum < ubi32_to_cpu(vid_hdr->used_ebs));
+ ubi_assert(len == ubi32_to_cpu(vid_hdr->data_size));
+
+ crc = ubi32_to_cpu(vid_hdr->data_crc);
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ }
+
+ err = ubi_io_read_data(ubi, buf, pnum, offset, len);
+ if (unlikely(err)) {
+ if (err == UBI_IO_BITFLIPS) {
+ scrub = 1;
+ err = 0;
+ } else if (err == -EBADMSG) {
+ if (vol->vol_type == UBI_DYNAMIC_VOLUME)
+ goto out_unlock;
+ scrub = 1;
+ if (!check) {
+ ubi_msg("force data checking");
+ check = 1;
+ goto retry;
+ }
+ } else
+ goto out_unlock;
+ }
+
+ if (check) {
+ crc1 = crc32(UBI_CRC32_INIT, buf, len);
+ if (unlikely(crc1 != crc)) {
+ ubi_warn("CRC error: calculated %#08x, must be %#08x",
+ crc1, crc);
+ err = -EBADMSG;
+ goto out_unlock;
+ }
+ }
+
+ if (unlikely(scrub))
+ err = ubi_wl_scrub_peb(ubi, pnum);
+
+ leb_read_unlock(ubi, vol_id, lnum);
+ return err;
+
+out_free:
+ ubi_free_vid_hdr(ubi, vid_hdr);
+out_unlock:
+ leb_read_unlock(ubi, vol_id, lnum);
+ return err;
+}
+
+/**
+ * recover_peb - recover from write failure.
+ * @ubi: UBI device description object
+ * @pnum: the physical eraseblock to recover
+ * @vol_id: volume ID
+ * @lnum: logical eraseblock number
+ * @buf: data which was not written because of the write failure
+ * @offset: offset of the failed write
+ * @len: how many bytes should have been written
+ *
+ * This function is called in case of a write failure and moves all good data
+ * from the potentially bad physical eraseblock to a good physical eraseblock.
+ * This function also writes the data which was not written due to the failure.
+ * Returns new physical eraseblock number in case of success, and a negative
+ * error code in case of failure.
+ */
+int recover_peb(struct ubi_device *ubi, int pnum, int vol_id, int lnum,
+ const void *buf, int offset, int len)
+{
+ int err, idx = vol_id2idx(ubi, vol_id), new_pnum, data_size, tries = 0;
+ struct ubi_volume *vol = ubi->volumes[idx];
+ struct ubi_vid_hdr *vid_hdr;
+ unsigned char *new_buf;
+
+ vid_hdr = ubi_zalloc_vid_hdr(ubi);
+ if (!vid_hdr) {
+ return -ENOMEM;
+ }
+
+retry:
+ new_pnum = ubi_wl_get_peb(ubi, UBI_DATA_UNKNOWN);
+ if (new_pnum < 0) {
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return new_pnum;
+ }
+
+ ubi_msg("recover PEB %d, move data to PEB %d", pnum, new_pnum);
+
+ err = ubi_io_read_vid_hdr(ubi, pnum, vid_hdr, 1);
+ if (err && err != UBI_IO_BITFLIPS) {
+ if (err > 0)
+ err = -EIO;
+ goto out_put;
+ }
+
+ vid_hdr->sqnum = cpu_to_ubi64(next_sqnum(ubi));
+ err = ubi_io_write_vid_hdr(ubi, new_pnum, vid_hdr);
+ if (err)
+ goto write_error;
+
+ data_size = offset + len;
+ new_buf = kmalloc(data_size, GFP_KERNEL);
+ if (unlikely(!new_buf)) {
+ err = -ENOMEM;
+ goto out_put;
+ }
+ memset(new_buf + offset, 0xFF, len);
+
+ /* Read everything before the area where the write failure happened */
+ if (offset > 0) {
+ err = ubi_io_read_data(ubi, new_buf, pnum, 0, offset);
+ if (err && err != UBI_IO_BITFLIPS) {
+ kfree(new_buf);
+ goto out_put;
+ }
+ }
+
+ memcpy(new_buf + offset, buf, len);
+
+ err = ubi_io_write_data(ubi, new_buf, new_pnum, 0, data_size);
+ if (err) {
+ kfree(new_buf);
+ goto write_error;
+ }
+
+ kfree(new_buf);
+ ubi_free_vid_hdr(ubi, vid_hdr);
+
+ vol->eba_tbl[lnum] = new_pnum;
+ ubi_wl_put_peb(ubi, pnum, 1);
+
+ ubi_msg("data was successfully recovered");
+ return 0;
+
+out_put:
+ ubi_wl_put_peb(ubi, new_pnum, 1);
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return err;
+
+write_error:
+ /*
+ * Bad luck? This physical eraseblock is bad too? Crud. Let's try to
+ * get another one.
+ */
+ ubi_warn("failed to write to PEB %d", new_pnum);
+ ubi_wl_put_peb(ubi, new_pnum, 1);
+ if (++tries > UBI_IO_RETRIES) {
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return err;
+ }
+ ubi_msg("try again");
+ goto retry;
+}
+
+/**
+ * ubi_eba_write_leb - write data to dynamic volume.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ * @lnum: logical eraseblock number
+ * @buf: the data to write
+ * @offset: offset within the logical eraseblock where to write
+ * @len: how many bytes to write
+ * @dtype: data type
+ *
+ * This function writes data to logical eraseblock @lnum of a dynamic volume
+ * @vol_id. Returns zero in case of success and a negative error code in case
+ * of failure. In case of error, it is possible that something was still
+ * written to the flash media, but may be some garbage.
+ */
+int ubi_eba_write_leb(struct ubi_device *ubi, int vol_id, int lnum,
+ const void *buf, int offset, int len,
+ enum ubi_data_type dtype)
+{
+ int idx = vol_id2idx(ubi, vol_id), err, pnum, tries = 0;
+ struct ubi_volume *vol = ubi->volumes[idx];
+ struct ubi_vid_hdr *vid_hdr;
+
+ if (unlikely(ubi->ro_mode))
+ return -EROFS;
+
+ err = leb_write_lock(ubi, vol_id, lnum);
+ if (unlikely(err))
+ return err;
+
+ pnum = vol->eba_tbl[lnum];
+ if (pnum >= 0) {
+ dbg_eba("write %d bytes at offset %d of LEB %d:%d, PEB %d",
+ len, offset, vol_id, lnum, pnum);
+
+ err = ubi_io_write_data(ubi, buf, pnum, offset, len);
+ if (unlikely(err)) {
+ ubi_warn("failed to write data to PEB %d", pnum);
+ if (err == -EIO && ubi->bad_allowed)
+ err = recover_peb(ubi, pnum, vol_id, lnum, buf, offset, len);
+ if (err)
+ ubi_ro_mode(ubi);
+ }
+ leb_write_unlock(ubi, vol_id, lnum);
+ return err;
+ }
+
+ /*
+ * The logical eraseblock is not mapped. We have to get a free physical
+ * eraseblock and write the volume identifier header there first.
+ */
+ vid_hdr = ubi_zalloc_vid_hdr(ubi);
+ if (unlikely(!vid_hdr)) {
+ leb_write_unlock(ubi, vol_id, lnum);
+ return -ENOMEM;
+ }
+
+ vid_hdr->vol_type = UBI_VID_DYNAMIC;
+ vid_hdr->sqnum = cpu_to_ubi64(next_sqnum(ubi));
+ vid_hdr->vol_id = cpu_to_ubi32(vol_id);
+ vid_hdr->lnum = cpu_to_ubi32(lnum);
+ vid_hdr->compat = ubi_get_compat(ubi, vol_id);
+ vid_hdr->data_pad = cpu_to_ubi32(vol->data_pad);
+
+retry:
+ pnum = ubi_wl_get_peb(ubi, dtype);
+ if (unlikely(pnum < 0)) {
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ leb_write_unlock(ubi, vol_id, lnum);
+ return pnum;
+ }
+
+ dbg_eba("write VID hdr and %d bytes at offset %d of LEB %d:%d, PEB %d",
+ len, offset, vol_id, lnum, pnum);
+
+ err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr);
+ if (unlikely(err)) {
+ ubi_warn("failed to write VID header to LEB %d:%d, PEB %d",
+ vol_id, lnum, pnum);
+ goto write_error;
+ }
+
+ err = ubi_io_write_data(ubi, buf, pnum, offset, len);
+ if (unlikely(err)) {
+ ubi_warn("failed to write %d bytes at offset %d of LEB %d:%d, "
+ "PEB %d", len, offset, vol_id, lnum, pnum);
+ goto write_error;
+ }
+
+ vol->eba_tbl[lnum] = pnum;
+
+ leb_write_unlock(ubi, vol_id, lnum);
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return 0;
+
+write_error:
+ if (err != -EIO || !ubi->bad_allowed) {
+ ubi_ro_mode(ubi);
+ leb_write_unlock(ubi, vol_id, lnum);
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return err;
+ }
+
+ /*
+ * Fortunately, this is the first write operation to this physical
+ * eraseblock, so just put it and request a new one. We assume that if
+ * this physical eraseblock went bad, the erase code will handle that.
+ */
+ err = ubi_wl_put_peb(ubi, pnum, 1);
+ if (err || ++tries > UBI_IO_RETRIES) {
+ ubi_ro_mode(ubi);
+ leb_write_unlock(ubi, vol_id, lnum);
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return err;
+ }
+
+ vid_hdr->sqnum = cpu_to_ubi64(next_sqnum(ubi));
+ ubi_msg("try another PEB");
+ goto retry;
+}
+
+/**
+ * ubi_eba_write_leb_st - write data to static volume.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ * @lnum: logical eraseblock number
+ * @buf: data to write
+ * @len: how many bytes to write
+ * @dtype: data type
+ * @used_ebs: how many logical eraseblocks will this volume contain
+ *
+ * This function writes data to logical eraseblock @lnum of static volume
+ * @vol_id. The @used_ebs argument should contain total number of logical
+ * eraseblock in this static volume.
+ *
+ * When writing to the last logical eraseblock, the @len argument doesn't have
+ * to be aligned to the minimal I/O unit size. Instead, it has to be equivalent
+ * to the real data size, although the @buf buffer has to contain the
+ * alignment. In all other cases, @len has to be aligned.
+ *
+ * It is prohibited to write more then once to logical eraseblocks of static
+ * volumes. This function returns zero in case of success and a negative error
+ * code in case of failure.
+ */
+int ubi_eba_write_leb_st(struct ubi_device *ubi, int vol_id, int lnum,
+ const void *buf, int len, enum ubi_data_type dtype,
+ int used_ebs)
+{
+ int err, pnum, tries = 0, data_size = len;
+ int idx = vol_id2idx(ubi, vol_id);
+ struct ubi_volume *vol = ubi->volumes[idx];
+ struct ubi_vid_hdr *vid_hdr;
+ uint32_t crc;
+
+ if (unlikely(ubi->ro_mode))
+ return -EROFS;
+
+ if (lnum == used_ebs - 1)
+ /* If this is the last LEB @len may be unaligned */
+ len = ubi_align_up(data_size, ubi->min_io_size);
+ else
+ ubi_assert(len % ubi->min_io_size == 0);
+
+ vid_hdr = ubi_zalloc_vid_hdr(ubi);
+ if (unlikely(!vid_hdr))
+ return -ENOMEM;
+
+ err = leb_write_lock(ubi, vol_id, lnum);
+ if (unlikely(err)) {
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return err;
+ }
+
+ vid_hdr->sqnum = cpu_to_ubi64(next_sqnum(ubi));
+ vid_hdr->vol_id = cpu_to_ubi32(vol_id);
+ vid_hdr->lnum = cpu_to_ubi32(lnum);
+ vid_hdr->compat = ubi_get_compat(ubi, vol_id);
+ vid_hdr->data_pad = cpu_to_ubi32(vol->data_pad);
+
+ crc = crc32(UBI_CRC32_INIT, buf, data_size);
+ vid_hdr->vol_type = UBI_VID_STATIC;
+ vid_hdr->data_size = cpu_to_ubi32(data_size);
+ vid_hdr->used_ebs = cpu_to_ubi32(used_ebs);
+ vid_hdr->data_crc = cpu_to_ubi32(crc);
+
+retry:
+ pnum = ubi_wl_get_peb(ubi, dtype);
+ if (unlikely(pnum < 0)) {
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ leb_write_unlock(ubi, vol_id, lnum);
+ return pnum;
+ }
+
+ dbg_eba("write VID hdr and %d bytes at LEB %d:%d, PEB %d, used_ebs %d",
+ len, vol_id, lnum, pnum, used_ebs);
+
+ err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr);
+ if (unlikely(err)) {
+ ubi_warn("failed to write VID header to LEB %d:%d, PEB %d",
+ vol_id, lnum, pnum);
+ goto write_error;
+ }
+
+ err = ubi_io_write_data(ubi, buf, pnum, 0, len);
+ if (unlikely(err)) {
+ ubi_warn("failed to write %d bytes of data to PEB %d",
+ len, pnum);
+ goto write_error;
+ }
+
+ ubi_assert(vol->eba_tbl[lnum] < 0);
+ vol->eba_tbl[lnum] = pnum;
+
+ leb_write_unlock(ubi, vol_id, lnum);
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return 0;
+
+write_error:
+ if (err != -EIO || !ubi->bad_allowed) {
+ /*
+ * This flash device does not admit of bad eraseblocks or
+ * something nasty and unexpected happened. Switch to read-only
+ * mode just in case.
+ */
+ ubi_ro_mode(ubi);
+ leb_write_unlock(ubi, vol_id, lnum);
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return err;
+ }
+
+ err = ubi_wl_put_peb(ubi, pnum, 1);
+ if (err || ++tries > UBI_IO_RETRIES) {
+ ubi_ro_mode(ubi);
+ leb_write_unlock(ubi, vol_id, lnum);
+ ubi_free_vid_hdr(ubi, vid_hdr);
+ return err;
+ }
+
+ vid_hdr->sqnum = cpu_to_ubi64(next_sqnum(ubi));
+ ubi_msg("try another PEB");
+ goto retry;
+}
+
+/**
+ * ltree_entry_ctor - lock tree entries slab cache constructor.
+ * @obj: the lock-tree entry to construct
+ * @cache: the lock tree entry slab cache
+ * @flags: constructor flags
+ */
+static void ltree_entry_ctor(void *obj, struct kmem_cache *cache,
+ unsigned long flags)
+{
+ struct ltree_entry *le = obj;
+
+ if ((flags & (SLAB_CTOR_VERIFY | SLAB_CTOR_CONSTRUCTOR)) !=
+ SLAB_CTOR_CONSTRUCTOR)
+ return;
+
+ le->users = 0;
+ init_rwsem(&le->mutex);
+}
+
+/**
+ * ubi_eba_copy_leb - copy logical eraseblock.
+ * @ubi: UBI device description object
+ * @from: physical eraseblock number from where to copy
+ * @to: physical eraseblock number where to copy
+ * @vid_hdr: VID header of the @from physical eraseblock
+ *
+ * This function copies logical eraseblock from physical eraseblock @from to
+ * physical eraseblock @to. The @vid_hdr buffer may be changed by this
+ * function. Returns zero in case of success, %UBI_IO_BITFLIPS if the operation
+ * was canceled because bit-flips were detected at the target PEB, and a
+ * negative error code in case of failure.
+ */
+int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
+ struct ubi_vid_hdr *vid_hdr)
+{
+ int err, vol_id, lnum, data_size, aldata_size, pnum, idx;
+ struct ubi_volume *vol;
+ uint32_t crc;
+ void *buf, *buf1 = NULL;
+
+ vol_id = ubi32_to_cpu(vid_hdr->vol_id);
+ lnum = ubi32_to_cpu(vid_hdr->lnum);
+
+ dbg_eba("copy LEB %d:%d, PEB %d to PEB %d", vol_id, lnum, from, to);
+
+ if (vid_hdr->vol_type == UBI_VID_STATIC) {
+ data_size = ubi32_to_cpu(vid_hdr->data_size);
+ aldata_size = ubi_align_up(data_size, ubi->min_io_size);
+ } else
+ data_size = aldata_size =
+ ubi->leb_size - ubi32_to_cpu(vid_hdr->data_pad);
+
+ buf = kmalloc(aldata_size, GFP_KERNEL);
+ if (unlikely(!buf))
+ return -ENOMEM;
+
+ /*
+ * We do not want anybody to write to this logical eraseblock while we
+ * are moving it, so we lock it.
+ */
+ err = leb_write_lock(ubi, vol_id, lnum);
+ if (unlikely(err)) {
+ kfree(buf);
+ return err;
+ }
+
+ /*
+ * But the logical eraseblock might have been put by this time.
+ * Cancel if it is true.
+ */
+ idx = vol_id2idx(ubi, vol_id);
+
+ /*
+ * We may race with volume deletion/resize, so we have to hold
+ * @ubi->volumes_lock.
+ */
+ spin_lock(&ubi->volumes_lock);
+ vol = ubi->volumes[idx];
+ if (!vol) {
+ dbg_eba("volume %d was removed meanwhile", vol_id);
+ spin_unlock(&ubi->volumes_lock);
+ goto out_unlock;
+ }
+
+ pnum = vol->eba_tbl[lnum];
+ if (pnum != from) {
+ dbg_eba("LEB %d:%d is no longer mapped to PEB %d, mapped to "
+ "PEB %d, cancel", vol_id, lnum, from, pnum);
+ spin_unlock(&ubi->volumes_lock);
+ goto out_unlock;
+ }
+ spin_unlock(&ubi->volumes_lock);
+
+ /* OK, now the LEB is locked and we can safely start moving it */
+
+ dbg_eba("read %d bytes of data", aldata_size);
+ err = ubi_io_read_data(ubi, buf, from, 0, aldata_size);
+ if (unlikely(err) && err != UBI_IO_BITFLIPS) {
+ ubi_warn("error %d while reading data from PEB %d",
+ err, from);
+ goto out_unlock;
+ }
+
+ /*
+ * Now we have got to calculate how much data we have to to copy. In
+ * case of a static volume it is fairly easy - the VID header contains
+ * the data size. In case of a dynamic volume it is more difficult - we
+ * have to read the contents, cut 0xFF bytes from the end and copy only
+ * the first part. We must do this to avoid writing 0xFF bytes as it
+ * may have some side-effects. And not only this. It is important not
+ * to include those 0xFFs to CRC because later the they may be filled
+ * by data.
+ */
+ if (vid_hdr->vol_type == UBI_VID_DYNAMIC)
+ aldata_size = data_size =
+ ubi_calc_data_len(ubi, buf, data_size);
+
+ cond_resched();
+ crc = crc32(UBI_CRC32_INIT, buf, data_size);
+ cond_resched();
+
+ /*
+ * It may turn out to me that the whole @from physical eraseblock
+ * contains only 0xFF bytes. Then we have to only write the VID header
+ * and do not write any data. This also means we should not set
+ * @vid_hdr->copy_flag, @vid_hdr->data_size, and @vid_hdr->data_crc.
+ */
+ if (likely(data_size > 0)) {
+ vid_hdr->copy_flag = 1;
+ vid_hdr->data_size = cpu_to_ubi32(data_size);
+ vid_hdr->data_crc = cpu_to_ubi32(crc);
+ }
+ vid_hdr->sqnum = cpu_to_ubi64(next_sqnum(ubi));
+
+ err = ubi_io_write_vid_hdr(ubi, to, vid_hdr);
+ if (unlikely(err))
+ goto out_unlock;
+
+ cond_resched();
+
+ /* Read the VID header back and check if it was written correctly */
+ err = ubi_io_read_vid_hdr(ubi, to, vid_hdr, 1);
+ if (unlikely(err)) {
+ if (err != UBI_IO_BITFLIPS)
+ ubi_warn("cannot read VID header back from PEB %d", to);
+ goto out_unlock;
+ }
+
+ if (likely(data_size > 0)) {
+ err = ubi_io_write_data(ubi, buf, to, 0, aldata_size);
+ if (unlikely(err))
+ goto out_unlock;
+
+ /*
+ * We've written the data and are going to read it back to make
+ * sure it was written correctly.
+ */
+ buf1 = kmalloc(aldata_size, GFP_KERNEL);
+ if (unlikely(!buf1)) {
+ err = -ENOMEM;
+ goto out_unlock;
+ }
+
+ cond_resched();
+
+ err = ubi_io_read_data(ubi, buf1, to, 0, aldata_size);
+ if (unlikely(err)) {
+ if (err != UBI_IO_BITFLIPS)
+ ubi_warn("cannot read data back from PEB %d",
+ to);
+ goto out_unlock;
+ }
+
+ cond_resched();
+
+ if (unlikely(memcmp(buf, buf1, aldata_size))) {
+ ubi_warn("read data back from PEB %d - it is different",
+ to);
+ goto out_unlock;
+ }
+ }
+
+ ubi_assert(vol->eba_tbl[lnum] == from);
+ vol->eba_tbl[lnum] = to;
+
+ leb_write_unlock(ubi, vol_id, lnum);
+ kfree(buf);
+ kfree(buf1);
+
+ return 0;
+
+out_unlock:
+ leb_write_unlock(ubi, vol_id, lnum);
+ kfree(buf);
+ kfree(buf1);
+ return err;
+}
+
+/**
+ * ubi_eba_init_scan - initialize the EBA unit using scanning information.
+ * @ubi: UBI device description object
+ * @si: scanning information
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+int ubi_eba_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si)
+{
+ int i, j, err, num_volumes;
+ struct ubi_scan_volume *sv;
+ struct ubi_volume *vol;
+ struct ubi_scan_leb *seb;
+ struct rb_node *rb;
+
+ dbg_eba("initialize EBA unit");
+
+ spin_lock_init(&ubi->ltree_lock);
+ ubi->ltree = RB_ROOT;
+
+ if (ubi_devices_cnt == 0) {
+ ltree_slab = kmem_cache_create("ubi_ltree_slab",
+ sizeof(struct ltree_entry), 0,
+ 0, <ree_entry_ctor, NULL);
+ if (!ltree_slab)
+ return -ENOMEM;
+ }
+
+ ubi->global_sqnum = si->max_sqnum + 1;
+ num_volumes = ubi->vtbl_slots + UBI_INT_VOL_COUNT;
+
+ for (i = 0; i < num_volumes; i++) {
+ vol = ubi->volumes[i];
+ if (!vol)
+ continue;
+
+ cond_resched();
+
+ vol->eba_tbl = kmalloc(vol->reserved_pebs * sizeof(int),
+ GFP_KERNEL);
+ if (unlikely(!vol->eba_tbl)) {
+ err = -ENOMEM;
+ goto out_free;
+ }
+
+ for (j = 0; j < vol->reserved_pebs; j++)
+ vol->eba_tbl[j] = UBI_LEB_UNMAPPED;
+
+ sv = ubi_scan_find_sv(si, idx2vol_id(ubi, i));
+ if (!sv)
+ continue;
+
+ ubi_rb_for_each_entry(rb, seb, &sv->root, u.rb) {
+ if (seb->lnum >= vol->reserved_pebs)
+ /*
+ * This may happen in case of an unclean reboot
+ * during re-size.
+ */
+ ubi_scan_move_to_list(sv, seb, &si->erase);
+ vol->eba_tbl[seb->lnum] = seb->pnum;
+ }
+ }
+
+ if (ubi->bad_allowed) {
+ ubi_calculate_reserved(ubi);
+
+ if (ubi->avail_pebs < ubi->beb_rsvd_level) {
+ /* No enough free physical eraseblocks */
+ ubi->beb_rsvd_pebs = ubi->avail_pebs;
+ ubi_warn("cannot reserve enough PEBs for bad PEB "
+ "handling, reserved %d, need %d",
+ ubi->beb_rsvd_pebs, ubi->beb_rsvd_level);
+ } else
+ ubi->beb_rsvd_pebs = ubi->beb_rsvd_level;
+
+ ubi->avail_pebs -= ubi->beb_rsvd_pebs;
+ ubi->rsvd_pebs += ubi->beb_rsvd_pebs;
+ }
+
+ dbg_eba("EBA unit is initialized");
+ return 0;
+
+out_free:
+ for (i = 0; i < num_volumes; i++) {
+ if (!ubi->volumes[i])
+ continue;
+ kfree(ubi->volumes[i]->eba_tbl);
+ }
+ if (ubi_devices_cnt == 0)
+ kmem_cache_destroy(ltree_slab);
+ return err;
+}
+
+/**
+ * ubi_eba_close - close EBA unit.
+ * @ubi: UBI device description object
+ */
+void ubi_eba_close(const struct ubi_device *ubi)
+{
+ int i, num_volumes = ubi->vtbl_slots + UBI_INT_VOL_COUNT;
+
+ dbg_eba("close EBA unit");
+
+ for (i = 0; i < num_volumes; i++) {
+ if (!ubi->volumes[i])
+ continue;
+ kfree(ubi->volumes[i]->eba_tbl);
+ }
+ if (ubi_devices_cnt == 1)
+ kmem_cache_destroy(ltree_slab);
+}
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 11/20 take 4] UBI: kernel API functions
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (9 preceding siblings ...)
2007-03-23 16:43 ` [PATCH 10/20 take 4] UBI: EBA unit Artem Bityutskiy
@ 2007-03-23 16:43 ` Artem Bityutskiy
2007-03-23 16:43 ` [PATCH 12/20 take 4] UBI: update functionality Artem Bityutskiy
` (8 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:43 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 17600 bytes --]
diff -auNrp tmp-from/drivers/mtd/ubi/kapi.c tmp-to/drivers/mtd/ubi/kapi.c
--- tmp-from/drivers/mtd/ubi/kapi.c 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/kapi.c 2007-03-23 18:20:02.000000000 +0200
@@ -0,0 +1,545 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/* This file mostly implements UBI kernel API functions */
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <asm/div64.h>
+#include "ubi.h"
+
+/**
+ * ubi_get_device_info - get information about UBI device.
+ * @ubi_num: UBI device number
+ * @di: the information is stored here
+ *
+ * This function returns %0 in case of success and a %-ENODEV if there is no
+ * such UBI device.
+ */
+int ubi_get_device_info(int ubi_num, struct ubi_device_info *di)
+{
+ const struct ubi_device *ubi;
+
+ if (!try_module_get(THIS_MODULE))
+ return -ENODEV;
+
+ if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES ||
+ !ubi_devices[ubi_num]) {
+ module_put(THIS_MODULE);
+ return -ENODEV;
+ }
+
+ ubi = ubi_devices[ubi_num];
+ di->ubi_num = ubi->ubi_num;
+ di->leb_size = ubi->leb_size;
+ di->min_io_size = ubi->min_io_size;
+ di->ro_mode = ubi->ro_mode;
+ di->cdev = MKDEV(ubi->major, 0);
+ module_put(THIS_MODULE);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ubi_get_device_info);
+
+/**
+ * ubi_get_volume_info - get information about UBI volume.
+ * @desc: volume descriptor
+ * @vi: the information is stored here
+ */
+void ubi_get_volume_info(struct ubi_volume_desc *desc,
+ struct ubi_volume_info *vi)
+{
+ const struct ubi_volume *vol = desc->vol;
+ const struct ubi_device *ubi = vol->ubi;
+
+ vi->vol_id = vol->vol_id;
+ vi->ubi_num = ubi->ubi_num;
+ vi->size = vol->reserved_pebs;
+ vi->used_bytes = vol->used_bytes;
+ vi->vol_type = vol->vol_type;
+ vi->corrupted = vol->corrupted;
+ vi->upd_marker = vol->upd_marker;
+ vi->alignment = vol->alignment;
+ vi->usable_leb_size = vol->usable_leb_size;
+ vi->name_len = vol->name_len;
+ vi->name = vol->name;
+ vi->cdev = MKDEV(ubi->major, vi->vol_id + 1);
+}
+EXPORT_SYMBOL_GPL(ubi_get_volume_info);
+
+/**
+ * ubi_open_volume - open UBI volume.
+ * @ubi_num: UBI device number
+ * @vol_id: volume ID
+ * @mode: open mode
+ *
+ * The @mode parameter specifies if the volume should be opened in read-only
+ * mode, read-write mode, or exclusive mode. The exclusive mode guarantees that
+ * nobody else will be able to open this volume. UBI allows to have many volume
+ * readers and one writer at a time.
+ *
+ * If a static volume is being opened for the first time since boot, it will be
+ * checked by this function, which means it will be fully read and the CRC
+ * checksum of each logical eraseblock will be checked.
+ *
+ * This function returns volume descriptor in case of success and a negative
+ * error code in case of failure.
+ */
+struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode)
+{
+ int err;
+ struct ubi_volume_desc *desc;
+ struct ubi_device *ubi = ubi_devices[ubi_num];
+ struct ubi_volume *vol;
+
+ dbg_msg("open device %d volume %d, mode %d", ubi_num, vol_id, mode);
+
+ err = -ENODEV;
+ if (!try_module_get(THIS_MODULE))
+ return ERR_PTR(err);
+
+ if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES || !ubi)
+ goto out_put;
+
+ err = -EINVAL;
+ if (vol_id < 0 || vol_id >= ubi->vtbl_slots)
+ goto out_put;
+ if (mode != UBI_READONLY && mode != UBI_READWRITE &&
+ mode != UBI_EXCLUSIVE)
+ goto out_put;
+
+ desc = kmalloc(sizeof(struct ubi_volume_desc), GFP_KERNEL);
+ if (!desc) {
+ err = -ENOMEM;
+ goto out_put;
+ }
+
+ spin_lock(&ubi->volumes_lock);
+ vol = ubi->volumes[vol_id];
+ if (!vol) {
+ err = -ENODEV;
+ goto out_unlock;
+ }
+
+ err = -EBUSY;
+ switch (mode) {
+ case UBI_READONLY:
+ if (vol->exclusive)
+ goto out_unlock;
+ vol->readers += 1;
+ break;
+
+ case UBI_READWRITE:
+ if (vol->exclusive || vol->writers > 0)
+ goto out_unlock;
+ vol->writers += 1;
+ break;
+
+ case UBI_EXCLUSIVE:
+ if (vol->exclusive || vol->writers || vol->readers)
+ goto out_unlock;
+ vol->exclusive = 1;
+ break;
+ }
+ spin_unlock(&ubi->volumes_lock);
+
+ desc->vol = vol;
+ desc->mode = mode;
+
+ /*
+ * To prevent simultaneous checks of the same volume we use @vtbl_mutex,
+ * although it is not the purpose it was introduced for.
+ */
+ mutex_lock(&ubi->vtbl_mutex);
+ if (!vol->checked) {
+ /*
+ * This is the first open - check the volume. If it is
+ * corrupted, still return success, but mark it as corrupted,
+ * so %-EUCLEAN will be returned on any further read.
+ */
+ err = ubi_check_volume(ubi, vol_id);
+ if (err < 0) {
+ mutex_unlock(&ubi->vtbl_mutex);
+ ubi_close_volume(desc);
+ return ERR_PTR(err);
+ }
+ if (err == 1) {
+ ubi_warn("volume %d on UBI device %d is corrupted",
+ vol_id, ubi->ubi_num);
+ vol->corrupted = 1;
+ }
+ vol->checked = 1;
+ }
+ mutex_unlock(&ubi->vtbl_mutex);
+ return desc;
+
+out_unlock:
+ spin_unlock(&ubi->volumes_lock);
+ kfree(desc);
+out_put:
+ module_put(THIS_MODULE);
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(ubi_open_volume);
+
+/**
+ * ubi_open_volume_nm - open UBI volume by name.
+ * @ubi_num: UBI device number
+ * @name: volume name
+ * @mode: open mode
+ *
+ * This function is similar to 'ubi_open_volume()', but opens a volume by name.
+ */
+struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name,
+ int mode)
+{
+ int i, vol_id = -1, len;
+ struct ubi_volume_desc *ret;
+ struct ubi_device *ubi;
+
+ dbg_msg("open volume %s, mode %d", name, mode);
+
+ if (!name)
+ return ERR_PTR(-EINVAL);
+
+ len = strnlen(name, UBI_VOL_NAME_MAX + 1);
+ if (len > UBI_VOL_NAME_MAX)
+ return ERR_PTR(-EINVAL);
+
+ ret = ERR_PTR(-ENODEV);
+ if (!try_module_get(THIS_MODULE))
+ return ret;
+
+ if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES || !ubi_devices[ubi_num])
+ goto out_put;
+
+ ubi = ubi_devices[ubi_num];
+
+ spin_lock(&ubi->volumes_lock);
+ /* Walk all volumes of this UBI device */
+ for (i = 0; i < ubi->vtbl_slots; i++) {
+ struct ubi_volume *vol = ubi->volumes[i];
+
+ if (vol && len == vol->name_len && !strcmp(name, vol->name)) {
+ vol_id = i;
+ break;
+ }
+ }
+ spin_unlock(&ubi->volumes_lock);
+
+ if (vol_id < 0)
+ goto out_put;
+
+ ret = ubi_open_volume(ubi_num, vol_id, mode);
+
+out_put:
+ module_put(THIS_MODULE);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ubi_open_volume_nm);
+
+/**
+ * ubi_close_volume - close UBI volume.
+ * @desc: volume descriptor
+ */
+void ubi_close_volume(struct ubi_volume_desc *desc)
+{
+ struct ubi_volume *vol = desc->vol;
+
+ dbg_msg("close volume %d, mode %d", vol->vol_id, desc->mode);
+
+ spin_lock(&vol->ubi->volumes_lock);
+ switch (desc->mode) {
+ case UBI_READONLY:
+ vol->readers -= 1;
+ break;
+ case UBI_READWRITE:
+ vol->writers -= 1;
+ break;
+ case UBI_EXCLUSIVE:
+ vol->exclusive = 0;
+ }
+ spin_unlock(&vol->ubi->volumes_lock);
+
+ kfree(desc);
+ module_put(THIS_MODULE);
+}
+EXPORT_SYMBOL_GPL(ubi_close_volume);
+
+/**
+ * ubi_eraseblock_read - read data.
+ * @desc: volume descriptor
+ * @lnum: logical eraseblock number to read from
+ * @buf: buffer where to store the read data
+ * @offset: offset within the logical eraseblock to read from
+ * @len: how many bytes to read
+ * @check: whether UBI has to check the read data's CRC or not.
+ *
+ * This function reads data from offset @offset of logical eraseblock @lnum and
+ * stores the data at @buf. When reading from static volumes, @check specifies
+ * whether the data has to be checked or not. If yes, the whole logical
+ * eraseblock will be read and its CRC checksum will be checked (i.e., the CRC
+ * checksum is per-eraseblock). So checking may substantially slow down the
+ * read speed. The @check argument is ignored for dynamic volumes.
+ *
+ * In case of success, this function returns zero. In case of failure, this
+ * function returns a negative error code.
+ *
+ * %-EBADMSG error code is returned:
+ * o for both static and dynamic volumes if MTD driver has detected a data
+ * integrity problem (unrecoverable ECC checksum mismatch in case of NAND);
+ * o for static volumes in case of data CRC mismatch.
+ *
+ * If a corrupted UBI volume is read, this function never returns zero, but
+ * %-EUCLEAN is returned instead, even though the data was read without errors
+ * because the corruption did not affect this particular piece of data
+ * *otherwise %-EBADMSG would have been returned). Thus, %-EUCLEAN just means
+ * that the read static volume is corrupted, but the read data is actually OK.
+ * %-EUCLEAN is not returned for dynamic volumes, because UBI does not protect
+ * their contents.
+ *
+ * If the volume is damaged because of an interrupted update this function just
+ * returns immediately with %-EBADF error code.
+ */
+int ubi_eraseblock_read(struct ubi_volume_desc *desc, int lnum, char *buf,
+ int offset, int len, int check)
+{
+ struct ubi_volume *vol = desc->vol;
+ struct ubi_device *ubi = vol->ubi;
+ int err, vol_id = vol->vol_id;
+
+ dbg_msg("read %d bytes from LEB %d:%d:%d", len, vol_id, lnum, offset);
+
+ if (unlikely(vol_id < 0 || vol_id >= ubi->vtbl_slots ||
+ lnum < 0 || lnum >= vol->used_ebs || offset < 0 ||
+ len < 0 || offset + len > vol->usable_leb_size))
+ return -EINVAL;
+
+ if (unlikely(vol->vol_type == UBI_STATIC_VOLUME &&
+ lnum == vol->used_ebs - 1 &&
+ offset + len > vol->last_eb_bytes))
+ return -EINVAL;
+
+ if (unlikely(vol->upd_marker))
+ return -EBADF;
+ if (unlikely(len == 0))
+ return 0;
+
+ err = ubi_eba_read_leb(ubi, vol_id, lnum, buf, offset, len, check);
+ if (unlikely(err && err == -EBADMSG
+ && vol->vol_type == UBI_STATIC_VOLUME)) {
+ ubi_warn("mark volume %d as corrupted", vol_id);
+ vol->corrupted = 1;
+ err = -EUCLEAN;
+ }
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(ubi_eraseblock_read);
+
+/**
+ * ubi_eraseblock_write - write data.
+ * @desc: volume descriptor
+ * @lnum: logical eraseblock number to write to
+ * @buf: data to write
+ * @offset: offset within the logical eraseblock where to write
+ * @len: how many bytes to write
+ * @dtype: expected data type
+ *
+ * This function writes @len bytes of data from @buf to offset @offset of
+ * logical eraseblock @lnum. The @dtype argument describes expected lifetime of
+ * the data.
+ *
+ * This function takes care of physical eraseblock write failures. If write to
+ * the physical eraseblock write operation fails, the logical eraseblock is
+ * re-mapped to another physical eraseblock, the data is recovered, and the
+ * write finishes. UBI has a pool of reserved physical eraseblocks for this.
+ *
+ * If all the data were successfully written, zero is returned. If an error
+ * occurred and UBI has not been able to recover from it, this function returns
+ * a negative error code. Note, in case of an error, it is possible that
+ * something was still written to the flash media, but that may be some
+ * garbage.
+ *
+ * If the volume is damaged because of an interrupted update this function just
+ * returns immediately with %-EBADF code.
+ */
+int ubi_eraseblock_write(struct ubi_volume_desc *desc, int lnum,
+ const void *buf, int offset, int len, int dtype)
+{
+ struct ubi_volume *vol = desc->vol;
+ struct ubi_device *ubi = vol->ubi;
+ int vol_id = vol->vol_id;
+
+ dbg_msg("write %d bytes to LEB %d:%d:%d", len, vol_id, lnum, offset);
+
+ if (unlikely(vol_id < 0 || vol_id >= ubi->vtbl_slots))
+ return -EINVAL;
+
+ if (unlikely(desc->mode == UBI_READONLY ||
+ vol->vol_type == UBI_STATIC_VOLUME))
+ return -EROFS;
+
+ if (unlikely(lnum < 0 || lnum >= vol->reserved_pebs || offset < 0 ||
+ len < 0 || offset + len > vol->usable_leb_size ||
+ offset % ubi->min_io_size || len % ubi->min_io_size))
+ return -EINVAL;
+
+ if (unlikely(dtype != UBI_DATA_LONGTERM &&
+ dtype != UBI_DATA_SHORTTERM &&
+ dtype != UBI_DATA_UNKNOWN))
+ return -EINVAL;
+
+ if (unlikely(vol->upd_marker))
+ return -EBADF;
+
+ if (unlikely(len == 0))
+ return 0;
+
+ return ubi_eba_write_leb(ubi, vol_id, lnum, buf, offset, len, dtype);
+}
+EXPORT_SYMBOL_GPL(ubi_eraseblock_write);
+
+/**
+ * ubi_eraseblock_erase - erase logical eraseblock.
+ * @desc: volume descriptor
+ * @lnum: logical eraseblock number
+ *
+ * This function un-maps logical eraseblock @lnum and synchronously erases the
+ * correspondent physical eraseblock. Returns zero in case of success and a
+ * negative error code in case of failure.
+ *
+ * If the volume is damaged because of an interrupted update this function just
+ * returns immediately with %-EBADF code.
+ */
+int ubi_eraseblock_erase(struct ubi_volume_desc *desc, int lnum)
+{
+ struct ubi_volume *vol = desc->vol;
+ struct ubi_device *ubi = vol->ubi;
+ int err, vol_id = vol->vol_id;
+
+ dbg_msg("erase LEB %d:%d", vol_id, lnum);
+
+ if (unlikely(desc->mode == UBI_READONLY ||
+ vol->vol_type == UBI_STATIC_VOLUME))
+ return -EROFS;
+
+ if (unlikely(lnum < 0 || lnum >= vol->reserved_pebs))
+ return -EINVAL;
+
+ if (unlikely(vol->upd_marker))
+ return -EBADF;
+
+ err = ubi_eba_unmap_leb(ubi, vol_id, lnum);
+ if (unlikely(err))
+ return err;
+
+ return ubi_wl_flush(ubi);
+}
+EXPORT_SYMBOL_GPL(ubi_eraseblock_erase);
+
+/**
+ * ubi_eraseblock_unmap - un-map logical eraseblock.
+ * @desc: volume descriptor
+ * @lnum: logical eraseblock number
+ *
+ * This function un-maps logical eraseblock @lnum and schedules the
+ * corresponding physical eraseblock for erasure, so that it will eventually be
+ * physically erased in background. This operation is much faster then the
+ * erase operation.
+ *
+ * Unlike erase, the un-map operation does not guarantee that the logical
+ * eraseblock will contain all 0xFF bytes when UBI is initialized again. For
+ * example, if several logical eraseblocks are un-mapped, and an unclean reboot
+ * happens after this, the logical eraseblocks will not necessarily be
+ * un-mapped again when this MTD device is attached. They may actually be
+ * mapped to the same physical eraseblocks again. So, this function has to be
+ * used with care.
+ *
+ * In other words, when un-mapping a logical eraseblock, UBI does not store
+ * any information about this on the flash media, it just marks the logical
+ * eraseblock as "un-mapped" in RAM. If UBI is detached before the physical
+ * eraseblock is physically erased, it will be mapped again to the same logical
+ * eraseblock when the MTD device is attached again.
+ *
+ * The main and obvious use-case of this function is when the contents of a
+ * logical eraseblock has to be re-written. Then it is much more efficient to
+ * first un-map it, then write new data, rather then first erase it, then write
+ * new data. Note, once new data has been written to the logical eraseblock,
+ * UBI guarantees that the old contents has gone forever. In other words, if an
+ * unclean reboot happens after the logical eraseblock has been un-mapped and
+ * then written to, it will contain the last written data.
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure. If the volume is damaged because of an interrupted update
+ * this function just returns immediately with %-EBADF code.
+ */
+int ubi_eraseblock_unmap(struct ubi_volume_desc *desc, int lnum)
+{
+ struct ubi_volume *vol = desc->vol;
+ struct ubi_device *ubi = vol->ubi;
+ int vol_id = vol->vol_id;
+
+ dbg_msg("unmap LEB %d:%d", vol_id, lnum);
+
+ if (unlikely(desc->mode == UBI_READONLY ||
+ vol->vol_type == UBI_STATIC_VOLUME))
+ return -EROFS;
+
+ if (unlikely(lnum < 0 || lnum >= vol->reserved_pebs))
+ return -EINVAL;
+
+ if (unlikely(vol->upd_marker))
+ return -EBADF;
+
+ return ubi_eba_unmap_leb(ubi, vol_id, lnum);
+}
+EXPORT_SYMBOL_GPL(ubi_eraseblock_unmap);
+
+/**
+ * ubi_eraseblock_is_mapped - check if logical eraseblock is mapped.
+ * @desc: volume descriptor
+ * @lnum: logical eraseblock number
+ *
+ * This function checks if logical eraseblock @lnum is mapped to a physical
+ * eraseblock. If a logical eraseblock is un-mapped, this does not necessarily
+ * mean it will still be un-mapped after the UBI device is re-attached. The
+ * logical eraseblock may become mapped to the physical eraseblock it was last
+ * mapped to.
+ *
+ * This function returns %1 if the LEB is mapped, %0 if not, and a negative
+ * error code in case of failure. If the volume is damaged because of an
+ * interrupted update this function just returns immediately with %-EBADF error
+ * code.
+ */
+int ubi_eraseblock_is_mapped(struct ubi_volume_desc *desc, int lnum)
+{
+ struct ubi_volume *vol = desc->vol;
+
+ dbg_msg("test LEB %d:%d", vol->vol_id, lnum);
+
+ if (unlikely(lnum < 0 || lnum >= vol->reserved_pebs))
+ return -EINVAL;
+
+ if (unlikely(vol->upd_marker))
+ return -EBADF;
+
+ return !!vol->eba_tbl[lnum];
+}
+EXPORT_SYMBOL_GPL(ubi_eraseblock_is_mapped);
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 12/20 take 4] UBI: update functionality
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (10 preceding siblings ...)
2007-03-23 16:43 ` [PATCH 11/20 take 4] UBI: kernel API functions Artem Bityutskiy
@ 2007-03-23 16:43 ` Artem Bityutskiy
2007-03-23 16:44 ` [PATCH 13/20 take 4] UBI: volume management functionality Artem Bityutskiy
` (7 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:43 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 11030 bytes --]
diff -auNrp tmp-from/drivers/mtd/ubi/upd.c tmp-to/drivers/mtd/ubi/upd.c
--- tmp-from/drivers/mtd/ubi/upd.c 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/upd.c 2007-03-23 18:20:02.000000000 +0200
@@ -0,0 +1,348 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ * Copyright (c) Nokia Corporation, 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ *
+ * Jan 2007: Alexander Schmidt, hacked per-volume update.
+ */
+
+/*
+ * This file contains implementation of the volume update functionality.
+ *
+ * The update operation is based on the per-volume update marker which is
+ * stored in the volume table. The update marker is set before the update
+ * starts, and removed after the update has been finished. So if the update was
+ * interrupted by an unclean re-boot or due to some other reasons, the update
+ * marker stays on the flash media and UBI finds it when it attaches the MTD
+ * device next time. If the update marker is set for a volume, the volume is
+ * treated as damaged and most I/O operations are prohibited. Only a new update
+ * operation is allowed.
+ *
+ * Note, in general it is possible to implement the update operation as a
+ * transaction with a roll-back capability.
+ */
+
+#include <linux/err.h>
+#include <asm/uaccess.h>
+#include <asm/div64.h>
+#include "ubi.h"
+
+/**
+ * set_update_marker - set update marker.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ *
+ * This function sets the update marker flag for volume @vol_id. Returns zero
+ * in case of success and a negative error code in case of failure.
+ */
+static int set_update_marker(struct ubi_device *ubi, int vol_id)
+{
+ int err;
+ struct ubi_vtbl_record vtbl_rec;
+ struct ubi_volume *vol = ubi->volumes[vol_id];
+
+ dbg_msg("set update marker for volume %d", vol_id);
+
+ if (vol->upd_marker) {
+ ubi_assert(ubi->vtbl[vol_id].upd_marker);
+ dbg_msg("already set");
+ return 0;
+ }
+
+ memcpy(&vtbl_rec, &ubi->vtbl[vol_id], sizeof(struct ubi_vtbl_record));
+ vtbl_rec.upd_marker = 1;
+
+ err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
+ vol->upd_marker = 1;
+ return err;
+}
+
+/**
+ * clear_update_marker - clear update marker.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ * @bytes: new data size in bytes
+ *
+ * This function clears the update marker for volume @vol_id, sets new volume
+ * data size and clears the "corrupted" flag (static volumes only). Returns
+ * zero in case of success and a negative error code in case of failure.
+ */
+static int clear_update_marker(struct ubi_device *ubi, int vol_id, long long bytes)
+{
+ int err;
+ uint64_t tmp;
+ struct ubi_vtbl_record vtbl_rec;
+ struct ubi_volume *vol = ubi->volumes[vol_id];
+
+ dbg_msg("clear update marker for volume %d", vol_id);
+
+ memcpy(&vtbl_rec, &ubi->vtbl[vol_id], sizeof(struct ubi_vtbl_record));
+ ubi_assert(vol->upd_marker && vtbl_rec.upd_marker);
+ vtbl_rec.upd_marker = 0;
+
+ if (vol->vol_type == UBI_STATIC_VOLUME) {
+ vol->corrupted = 0;
+ vol->used_bytes = tmp = bytes;
+ vol->last_eb_bytes = do_div(tmp, vol->usable_leb_size);
+ vol->used_ebs = tmp;
+ if (vol->last_eb_bytes)
+ vol->used_ebs += 1;
+ else
+ vol->last_eb_bytes = vol->usable_leb_size;
+ }
+
+ err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
+ vol->upd_marker = 0;
+ return err;
+}
+
+/**
+ * ubi_start_update - start volume update.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ * @bytes: update bytes
+ *
+ * This function starts volume update operation. If @bytes is zero, the volume
+ * is just wiped out. Returns zero in case of success and a negative error code
+ * in case of failure.
+ */
+int ubi_start_update(struct ubi_device *ubi, int vol_id, long long bytes)
+{
+ int i, err;
+ uint64_t tmp;
+ struct ubi_volume *vol = ubi->volumes[vol_id];
+
+ dbg_msg("start update of volume %d, %llu bytes", vol_id, bytes);
+ vol->updating = 1;
+
+ err = set_update_marker(ubi, vol_id);
+ if (err)
+ return err;
+
+ /* Before updating - wipe out the volume */
+ for (i = 0; i < vol->reserved_pebs; i++) {
+ err = ubi_eba_unmap_leb(ubi, vol_id, i);
+ if (err)
+ return err;
+ }
+
+ if (bytes == 0) {
+ err = clear_update_marker(ubi, vol_id, 0);
+ if (err)
+ return err;
+ err = ubi_wl_flush(ubi);
+ if (!err)
+ vol->updating = 0;
+ }
+
+ vol->upd_buf = kmalloc(ubi->leb_size, GFP_KERNEL);
+ if (!vol->upd_buf)
+ return -ENOMEM;
+
+ tmp = bytes;
+ vol->upd_ebs = !!do_div(tmp, vol->usable_leb_size);
+ vol->upd_ebs += tmp;
+ vol->upd_bytes = bytes;
+ vol->upd_received = 0;
+ return 0;
+}
+
+/**
+ * write_leb - write update data.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ * @lnum: logical eraseblock number
+ * @buf: data to write
+ * @len: data size
+ * @used_ebs: how many logical eraseblocks will this volume contain (static
+ * volumes only)
+ *
+ * This function writes update data to corresponding logical eraseblock. In
+ * case of dynamic volume, this function checks if the data contains 0xFF bytes
+ * at the end. If yes, the 0xFF bytes are cut and not written. So if the whole
+ * buffer contains only 0xFF bytes, the LEB is left unmapped.
+ *
+ * The reason why we skip the trailing 0xFF bytes in case of dynamic volume is
+ * that we want to make sure that more data may be appended to the logical
+ * eraseblock in future. Indeed, writing 0xFF bytes may have side effects and
+ * this PEB won't be writable anymore. So if one writes the file-system image
+ * to the UBI volume where 0xFFs mean free space - UBI makes sure this free
+ * space is writable after the update.
+ *
+ * We do not do this for static volumes because they are read-only. But this
+ * also cannot be done because we have to store per-LEB CRC and the correct
+ * data length.
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int write_leb(struct ubi_device *ubi, int vol_id, int lnum, void *buf,
+ int len, int used_ebs)
+{
+ int err, l;
+ struct ubi_volume *vol = ubi->volumes[vol_id];
+
+ if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
+ l = ubi_align_up(len, ubi->min_io_size);
+ memset(buf + len, 0xFF, l - len);
+
+ l = ubi_calc_data_len(ubi, buf, l);
+ if (l == 0) {
+ dbg_msg("all %d bytes contain 0xFF - skip", len);
+ return 0;
+ }
+ if (len != l)
+ dbg_msg("skip last %d bytes (0xFF)", len - l);
+
+ err = ubi_eba_write_leb(ubi, vol_id, lnum, buf, 0, l,
+ UBI_DATA_UNKNOWN);
+ } else {
+ /*
+ * When writing static volume, and this is the last logical
+ * eraseblock, the length (@len) does not have to be aligned to
+ * the minimal flash I/O unit. The 'ubi_eba_write_leb_st()'
+ * function accepts exact (unaligned) length and stores it in
+ * the VID header. And it takes care of proper alignment by
+ * padding the buffer. Here we just make sure the padding will
+ * contain zeros, not random trash.
+ */
+ memset(buf + len, 0, vol->usable_leb_size - len);
+ err = ubi_eba_write_leb_st(ubi, vol_id, lnum, buf, len,
+ UBI_DATA_UNKNOWN, used_ebs);
+ }
+
+ return err;
+}
+
+/**
+ * ubi_more_update_data - write more update data.
+ * @vol: volume description object
+ * @buf: write data (user-space memory buffer)
+ * @count: how much bytes to write
+ *
+ * This function writes more data to the volume which is being updated. It may
+ * be called arbitrary number of times until all of the update data arrive.
+ * This function returns %0 in case of success, number of bytes written during
+ * the last call if the whole volume update was successfully finished, and a
+ * negative error code in case of failure.
+ */
+int ubi_more_update_data(struct ubi_device *ubi, int vol_id,
+ const void __user *buf, int count)
+{
+ uint64_t tmp;
+ struct ubi_volume *vol = ubi->volumes[vol_id];
+ int lnum, offs, err = 0, len, to_write = count;
+
+ dbg_msg("write %d of %lld bytes, %lld already passed",
+ count, vol->upd_bytes, vol->upd_received);
+
+ if (unlikely(ubi->ro_mode))
+ return -EROFS;
+
+ tmp = vol->upd_received;
+ offs = do_div(tmp, vol->usable_leb_size);
+ lnum = tmp;
+
+ if (vol->upd_received + count > vol->upd_bytes)
+ to_write = count = vol->upd_bytes - vol->upd_received;
+
+ /*
+ * When updating volumes, we accumulate whole logical eraseblock of
+ * data and write it at once.
+ */
+ if (offs != 0) {
+ /*
+ * This is a write to the middle of the logical eraseblock. We
+ * copy the data to our update buffer and wait for more data or
+ * flush it if the whole eraseblock is written or the update
+ * is finished.
+ */
+
+ len = vol->usable_leb_size - offs;
+ if (len > count)
+ len = count;
+
+ err = copy_from_user(vol->upd_buf + offs, buf, len);
+ if (unlikely(err))
+ return -EFAULT;
+
+ if (offs + len == vol->usable_leb_size ||
+ vol->upd_received + len == vol->upd_bytes) {
+ int flush_len = offs + len;
+
+ /*
+ * OK, we gathered either the whole eraseblock or this
+ * is the last chunk, it's time to flush the buffer.
+ */
+ ubi_assert(flush_len <= vol->usable_leb_size);
+ err = write_leb(ubi, vol_id, lnum, vol->upd_buf,
+ flush_len, vol->upd_ebs);
+ if (err)
+ return err;
+ }
+
+ vol->upd_received += len;
+ count -= len;
+ buf += len;
+ lnum += 1;
+ }
+
+ /*
+ * If we've got more to write, let's continue. At this point we know we
+ * are starting from the beginning of an eraseblock.
+ */
+ while (count) {
+ if (count > vol->usable_leb_size)
+ len = vol->usable_leb_size;
+ else
+ len = count;
+
+ err = copy_from_user(vol->upd_buf, buf, len);
+ if (unlikely(err))
+ return -EFAULT;
+
+ if (len == vol->usable_leb_size ||
+ vol->upd_received + len == vol->upd_bytes) {
+ err = write_leb(ubi, vol_id, lnum, vol->upd_buf, len,
+ vol->upd_ebs);
+ if (unlikely(err))
+ break;
+ }
+
+ vol->upd_received += len;
+ count -= len;
+ lnum += 1;
+ buf += len;
+ }
+
+ ubi_assert(vol->upd_received <= vol->upd_bytes);
+ if (vol->upd_received == vol->upd_bytes) {
+ /* The update is finished, clear the update marker */
+ err = clear_update_marker(ubi, vol_id, vol->upd_bytes);
+ if (err)
+ return err;
+ err = ubi_wl_flush(ubi);
+ if (err == 0) {
+ err = to_write;
+ kfree(vol->upd_buf);
+ vol->updating = 0;
+ }
+ }
+
+ return err;
+}
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 13/20 take 4] UBI: volume management functionality
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (11 preceding siblings ...)
2007-03-23 16:43 ` [PATCH 12/20 take 4] UBI: update functionality Artem Bityutskiy
@ 2007-03-23 16:44 ` Artem Bityutskiy
2007-03-23 16:44 ` [PATCH 14/20 take 4] UBI: character devices functionality Artem Bityutskiy
` (6 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:44 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 23189 bytes --]
diff -auNrp tmp-from/drivers/mtd/ubi/vmt.c tmp-to/drivers/mtd/ubi/vmt.c
--- tmp-from/drivers/mtd/ubi/vmt.c 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/vmt.c 2007-03-23 18:20:02.000000000 +0200
@@ -0,0 +1,811 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file contains implementation of volume creation, deletion, updating and
+ * resizing.
+ */
+
+#include <linux/err.h>
+#include <asm/div64.h>
+#include "ubi.h"
+
+#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
+static void paranoid_check_volumes(struct ubi_device *ubi);
+#else
+#define paranoid_check_volumes(ubi)
+#endif
+
+static ssize_t vol_attribute_show(struct device *dev,
+ struct device_attribute *attr, char *buf);
+
+/* Device attributes corresponding to files in '/<sysfs>/class/ubi/ubiX_Y' */
+static struct device_attribute vol_reserved_ebs =
+ __ATTR(reserved_ebs, S_IRUGO, vol_attribute_show, NULL);
+static struct device_attribute vol_type =
+ __ATTR(type, S_IRUGO, vol_attribute_show, NULL);
+static struct device_attribute vol_name =
+ __ATTR(name, S_IRUGO, vol_attribute_show, NULL);
+static struct device_attribute vol_corrupted =
+ __ATTR(corrupted, S_IRUGO, vol_attribute_show, NULL);
+static struct device_attribute vol_alignment =
+ __ATTR(alignment, S_IRUGO, vol_attribute_show, NULL);
+static struct device_attribute vol_usable_eb_size =
+ __ATTR(usable_eb_size, S_IRUGO, vol_attribute_show, NULL);
+static struct device_attribute vol_data_bytes =
+ __ATTR(data_bytes, S_IRUGO, vol_attribute_show, NULL);
+static struct device_attribute vol_upd_marker =
+ __ATTR(upd_marker, S_IRUGO, vol_attribute_show, NULL);
+
+/*
+ * "Show" method for files in '/<sysfs>/class/ubi/ubiX_Y/'.
+ *
+ * Consider a situation:
+ * A. process 1 opens a sysfs file related to volume Y, say
+ * /<sysfs>/class/ubi/ubiX_Y/reserved_ebs;
+ * B. process 2 removes volume Y;
+ * C. process 1 starts reading the /<sysfs>/class/ubi/ubiX_Y/reserved_ebs file;
+ *
+ * What we want to do in a situation like that is to return error when the file
+ * is read. This is done by means of the 'removed' flag and the 'vol_lock' of
+ * the UBI volume description object.
+ */
+static ssize_t vol_attribute_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int ret;
+ struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
+
+ spin_lock(&vol->ubi->volumes_lock);
+ if (vol->removed) {
+ spin_unlock(&vol->ubi->volumes_lock);
+ return -ENODEV;
+ }
+ if (attr == &vol_reserved_ebs)
+ ret = sprintf(buf, "%d\n", vol->reserved_pebs);
+ else if (attr == &vol_type) {
+ const char *tp;
+ tp = vol->vol_type == UBI_DYNAMIC_VOLUME ? "dynamic" : "static";
+ ret = sprintf(buf, "%s\n", tp);
+ } else if (attr == &vol_name)
+ ret = sprintf(buf, "%s\n", vol->name);
+ else if (attr == &vol_corrupted)
+ ret = sprintf(buf, "%d\n", vol->corrupted);
+ else if (attr == &vol_alignment)
+ ret = sprintf(buf, "%d\n", vol->alignment);
+ else if (attr == &vol_usable_eb_size) {
+ ret = sprintf(buf, "%d\n", vol->usable_leb_size);
+ } else if (attr == &vol_data_bytes)
+ ret = sprintf(buf, "%lld\n", vol->used_bytes);
+ else if (attr == &vol_upd_marker)
+ ret = sprintf(buf, "%d\n", vol->upd_marker);
+ else
+ BUG();
+ spin_unlock(&vol->ubi->volumes_lock);
+ return ret;
+}
+
+/* Release method for volume devices */
+static void vol_release(struct device *dev)
+{
+ struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
+ ubi_assert(vol->removed);
+ kfree(vol);
+}
+
+/**
+ * volume_sysfs_init - initialize sysfs for new volume.
+ * @ubi: UBI device description object
+ * @vol: volume description object
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ *
+ * Note, this function does not free allocated resources in case of failure -
+ * the caller does it. This is because this would cause release() here and the
+ * caller would oops.
+ */
+static int volume_sysfs_init(struct ubi_device *ubi, struct ubi_volume *vol)
+{
+ int err;
+
+ err = device_create_file(&vol->dev, &vol_reserved_ebs);
+ if (err)
+ return err;
+ err = device_create_file(&vol->dev, &vol_type);
+ if (err)
+ return err;
+ err = device_create_file(&vol->dev, &vol_name);
+ if (err)
+ return err;
+ err = device_create_file(&vol->dev, &vol_corrupted);
+ if (err)
+ return err;
+ err = device_create_file(&vol->dev, &vol_alignment);
+ if (err)
+ return err;
+ err = device_create_file(&vol->dev, &vol_usable_eb_size);
+ if (err)
+ return err;
+ err = device_create_file(&vol->dev, &vol_data_bytes);
+ if (err)
+ return err;
+ err = device_create_file(&vol->dev, &vol_upd_marker);
+ if (err)
+ return err;
+ return 0;
+}
+
+/**
+ * volume_sysfs_close - close sysfs for a volume.
+ * @vol: volume description object
+ */
+static void volume_sysfs_close(struct ubi_volume *vol)
+{
+ device_remove_file(&vol->dev, &vol_upd_marker);
+ device_remove_file(&vol->dev, &vol_data_bytes);
+ device_remove_file(&vol->dev, &vol_usable_eb_size);
+ device_remove_file(&vol->dev, &vol_alignment);
+ device_remove_file(&vol->dev, &vol_corrupted);
+ device_remove_file(&vol->dev, &vol_name);
+ device_remove_file(&vol->dev, &vol_type);
+ device_remove_file(&vol->dev, &vol_reserved_ebs);
+ device_unregister(&vol->dev);
+}
+
+/**
+ * ubi_create_volume - create volume.
+ * @ubi: UBI device description object
+ * @req: volume creation request
+ *
+ * This function creates volume described by @req. If @req->vol_id id
+ * %UBI_VOL_NUM_AUTO, this function automatically assigne ID to the new volume
+ * and saves it in @req->vol_id. Returns zero in case of success and a negative
+ * error code in case of failure.
+ */
+int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req)
+{
+ int i, err, vol_id = req->vol_id;
+ struct ubi_volume *vol;
+ struct ubi_vtbl_record vtbl_rec;
+ uint64_t bytes;
+
+ if (ubi->ro_mode)
+ return -EROFS;
+
+ vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL);
+ if (!vol)
+ return -ENOMEM;
+
+ spin_lock(&ubi->volumes_lock);
+
+ if (vol_id == UBI_VOL_NUM_AUTO) {
+ /* Find unused volume ID */
+ dbg_msg("search for vacant volume ID");
+ for (i = 0; i < ubi->vtbl_slots; i++)
+ if (!ubi->volumes[i]) {
+ vol_id = i;
+ break;
+ }
+
+ if (vol_id == UBI_VOL_NUM_AUTO) {
+ dbg_err("out of volume IDs");
+ err = -ENOSPC;
+ goto out_unlock;
+ }
+ req->vol_id = vol_id;
+ }
+
+ dbg_msg("volume ID %d, %llu bytes, type %d, name %s",
+ vol_id, (unsigned long long)req->bytes,
+ (int)req->vol_type, req->name);
+
+ /* Ensure that this volume does not exist */
+ err = -EEXIST;
+ if (ubi->volumes[vol_id]) {
+ dbg_err("volume %d already exists", vol_id);
+ goto out_unlock;
+ }
+
+ /* Ensure that the name is unique */
+ for (i = 0; i < ubi->vtbl_slots; i++)
+ if (ubi->volumes[i] &&
+ ubi->volumes[i]->name_len == req->name_len &&
+ strcmp(ubi->volumes[i]->name, req->name) == 0) {
+ dbg_err("volume \"%s\" exists (ID %d)", req->name, i);
+ goto out_unlock;
+ }
+
+ /* Calculate how many eraseblocks are requested */
+ vol->usable_leb_size = ubi->leb_size - ubi->leb_size % req->alignment;
+ bytes = req->bytes;
+ if (do_div(bytes, vol->usable_leb_size))
+ vol->reserved_pebs = 1;
+ vol->reserved_pebs += bytes;
+
+ /* Reserve physical eraseblocks */
+ if (vol->reserved_pebs > ubi->avail_pebs) {
+ dbg_err("not enough PEBs, only %d available", ubi->avail_pebs);
+ spin_unlock(&ubi->volumes_lock);
+ err = -ENOSPC;
+ goto out_unlock;
+ }
+ ubi->avail_pebs -= vol->reserved_pebs;
+ ubi->rsvd_pebs += vol->reserved_pebs;
+
+ vol->vol_id = vol_id;
+ vol->alignment = req->alignment;
+ vol->data_pad = ubi->leb_size % vol->alignment;
+ vol->vol_type = req->vol_type;
+ vol->name_len = req->name_len;
+ memcpy(vol->name, req->name, vol->name_len + 1);
+ vol->exclusive = 1;
+ vol->ubi = ubi;
+ ubi->volumes[vol_id] = vol;
+ spin_unlock(&ubi->volumes_lock);
+
+ /*
+ * Finish all pending erases because there may be some LEBs belonging
+ * to the same volume ID.
+ */
+ err = ubi_wl_flush(ubi);
+ if (err)
+ goto out_acc;
+
+ vol->eba_tbl = kmalloc(vol->reserved_pebs * sizeof(int), GFP_KERNEL);
+ if (!vol->eba_tbl) {
+ err = -ENOMEM;
+ goto out_acc;
+ }
+
+ for (i = 0; i < vol->reserved_pebs; i++)
+ vol->eba_tbl[i] = UBI_LEB_UNMAPPED;
+
+ if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
+ vol->used_ebs = vol->reserved_pebs;
+ vol->last_eb_bytes = vol->usable_leb_size;
+ vol->used_bytes = vol->used_ebs * vol->usable_leb_size;
+ } else {
+ bytes = vol->used_bytes;
+ vol->last_eb_bytes = do_div(bytes, vol->usable_leb_size);
+ vol->used_ebs = bytes;
+ if (vol->last_eb_bytes)
+ vol->used_ebs += 1;
+ else
+ vol->last_eb_bytes = vol->usable_leb_size;
+ }
+
+ /* Register character device for the volume */
+ cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
+ vol->cdev.owner = THIS_MODULE;
+ err = cdev_add(&vol->cdev, MKDEV(ubi->major, vol_id + 1), 1);
+ if (err) {
+ ubi_err("cannot add character device for volume %d", vol_id);
+ goto out_mapping;
+ }
+
+ err = ubi_create_gluebi(ubi, vol);
+ if (err)
+ goto out_cdev;
+
+ vol->dev.release = vol_release;
+ vol->dev.parent = &ubi->dev;
+ vol->dev.devt = MKDEV(ubi->major, vol->vol_id + 1);
+ vol->dev.class = ubi_class;
+ sprintf(&vol->dev.bus_id[0], "%s_%d", ubi->ubi_name, vol->vol_id);
+ err = device_register(&vol->dev);
+ if (err)
+ goto out_gluebi;
+
+ err = volume_sysfs_init(ubi, vol);
+ if (err)
+ goto out_sysfs;
+
+ /* Fill volume table record */
+ memset(&vtbl_rec, 0, sizeof(struct ubi_vtbl_record));
+ vtbl_rec.reserved_pebs = cpu_to_ubi32(vol->reserved_pebs);
+ vtbl_rec.alignment = cpu_to_ubi32(vol->alignment);
+ vtbl_rec.data_pad = cpu_to_ubi32(vol->data_pad);
+ vtbl_rec.name_len = cpu_to_ubi16(vol->name_len);
+ if (vol->vol_type == UBI_DYNAMIC_VOLUME)
+ vtbl_rec.vol_type = UBI_VID_DYNAMIC;
+ else
+ vtbl_rec.vol_type = UBI_VID_STATIC;
+ memcpy(vtbl_rec.name, vol->name, vol->name_len + 1);
+
+ err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
+ if (err)
+ goto out_sysfs;
+
+ spin_lock(&ubi->volumes_lock);
+ ubi->vol_count += 1;
+ vol->exclusive = 0;
+ spin_unlock(&ubi->volumes_lock);
+
+ paranoid_check_volumes(ubi);
+ return 0;
+
+out_gluebi:
+ err = ubi_destroy_gluebi(vol);
+out_cdev:
+ cdev_del(&vol->cdev);
+out_mapping:
+ kfree(vol->eba_tbl);
+out_acc:
+ spin_lock(&ubi->volumes_lock);
+ ubi->rsvd_pebs -= vol->reserved_pebs;
+ ubi->avail_pebs += vol->reserved_pebs;
+out_unlock:
+ spin_unlock(&ubi->volumes_lock);
+ kfree(vol);
+ return err;
+
+ /*
+ * We are registered, so @vol is destroyed in the release function and
+ * we have to de-initialize differently.
+ */
+out_sysfs:
+ err = ubi_destroy_gluebi(vol);
+ cdev_del(&vol->cdev);
+ kfree(vol->eba_tbl);
+ spin_lock(&ubi->volumes_lock);
+ ubi->rsvd_pebs -= vol->reserved_pebs;
+ ubi->avail_pebs += vol->reserved_pebs;
+ spin_unlock(&ubi->volumes_lock);
+ volume_sysfs_close(vol);
+ return err;
+}
+
+/**
+ * ubi_remove_volume - remove volume.
+ * @desc: volume descriptor
+ *
+ * This function removes volume described by @desc. The volume has to be opened
+ * in "exclusive" mode. Returns zero in case of success and a negative error
+ * code in case of failure.
+ */
+int ubi_remove_volume(struct ubi_volume_desc *desc)
+{
+ struct ubi_volume *vol = desc->vol;
+ struct ubi_device *ubi = vol->ubi;
+ int i, err, vol_id = vol->vol_id, reserved_pebs = vol->reserved_pebs;
+
+ dbg_msg("remove UBI volume %d", vol_id);
+ ubi_assert(desc->mode == UBI_EXCLUSIVE);
+ ubi_assert(vol == ubi->volumes[vol_id]);
+
+ if (ubi->ro_mode)
+ return -EROFS;
+
+ err = ubi_destroy_gluebi(vol);
+ if (err)
+ return err;
+
+ err = ubi_change_vtbl_record(ubi, vol_id, NULL);
+ if (err)
+ return err;
+
+ for (i = 0; i < vol->reserved_pebs; i++) {
+ err = ubi_eba_unmap_leb(ubi, vol_id, i);
+ if (err)
+ return err;
+ }
+
+ spin_lock(&ubi->volumes_lock);
+ vol->removed = 1;
+ ubi->volumes[vol_id] = NULL;
+ spin_unlock(&ubi->volumes_lock);
+
+ kfree(vol->eba_tbl);
+ vol->eba_tbl = NULL;
+ cdev_del(&vol->cdev);
+ volume_sysfs_close(vol);
+ kfree(desc);
+
+ spin_lock(&ubi->volumes_lock);
+ ubi->rsvd_pebs -= reserved_pebs;
+ ubi->avail_pebs += reserved_pebs;
+ i = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs;
+ if (i > 0) {
+ i = ubi->avail_pebs >= i ? i : ubi->avail_pebs;
+ ubi->avail_pebs -= i;
+ ubi->rsvd_pebs += i;
+ ubi->beb_rsvd_pebs += i;
+ if (i > 0)
+ ubi_msg("reserve more %d PEBs", i);
+ }
+ ubi->vol_count -= 1;
+ spin_unlock(&ubi->volumes_lock);
+
+ paranoid_check_volumes(ubi);
+ module_put(THIS_MODULE);
+ return 0;
+}
+
+/**
+ * ubi_resize_volume - re-size volume.
+ * @desc: volume descriptor
+ * @reserved_pebs: new size in physical eraseblocks
+ *
+ * This function returns zero in case of success, and a negative error code in
+ * case of failure.
+ */
+int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs)
+{
+ int i, err, pebs, *new_mapping;
+ struct ubi_volume *vol = desc->vol;
+ struct ubi_device *ubi = vol->ubi;
+ struct ubi_vtbl_record vtbl_rec;
+ int vol_id = vol->vol_id;
+
+ if (ubi->ro_mode)
+ return -EROFS;
+
+ dbg_msg("re-size volume %d to from %d to %d PEBs",
+ vol_id, vol->reserved_pebs, reserved_pebs);
+ ubi_assert(desc->mode == UBI_EXCLUSIVE);
+ ubi_assert(vol == ubi->volumes[vol_id]);
+
+ if (vol->vol_type == UBI_STATIC_VOLUME &&
+ reserved_pebs < vol->used_ebs) {
+ dbg_err("too small size %d, %d LEBs contain data",
+ reserved_pebs, vol->used_ebs);
+ return -EINVAL;
+ }
+
+ /* If the size is the same, we have nothing to do */
+ if (reserved_pebs == vol->reserved_pebs)
+ return 0;
+
+ new_mapping = kmalloc(reserved_pebs * sizeof(int), GFP_KERNEL);
+ if (!new_mapping)
+ return -ENOMEM;
+
+ for (i = 0; i < reserved_pebs; i++)
+ new_mapping[i] = UBI_LEB_UNMAPPED;
+
+ /* Reserve physical eraseblocks */
+ pebs = reserved_pebs - vol->reserved_pebs;
+ if (pebs > 0) {
+ spin_lock(&ubi->volumes_lock);
+ if (pebs > ubi->avail_pebs) {
+ dbg_err("not enough PEBs: requested %d, available %d",
+ pebs, ubi->avail_pebs);
+ spin_unlock(&ubi->volumes_lock);
+ err = -ENOSPC;
+ goto out_free;
+ }
+ ubi->avail_pebs -= pebs;
+ ubi->rsvd_pebs += pebs;
+ for (i = 0; i < vol->reserved_pebs; i++)
+ new_mapping[i] = vol->eba_tbl[i];
+ kfree(vol->eba_tbl);
+ vol->eba_tbl = new_mapping;
+ spin_unlock(&ubi->volumes_lock);
+ }
+
+ /* Change volume table record */
+ memcpy(&vtbl_rec, &ubi->vtbl[vol_id], sizeof(struct ubi_vtbl_record));
+ vtbl_rec.reserved_pebs = cpu_to_ubi32(reserved_pebs);
+ err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
+ if (err)
+ goto out_acc;
+
+ if (pebs < 0) {
+ for (i = 0; i < -pebs; i++) {
+ err = ubi_eba_unmap_leb(ubi, vol_id, reserved_pebs + i);
+ if (err)
+ goto out_acc;
+ }
+ spin_lock(&ubi->volumes_lock);
+ ubi->rsvd_pebs += pebs;
+ ubi->avail_pebs -= pebs;
+ pebs = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs;
+ if (pebs > 0) {
+ pebs = ubi->avail_pebs >= pebs ? pebs : ubi->avail_pebs;
+ ubi->avail_pebs -= pebs;
+ ubi->rsvd_pebs += pebs;
+ ubi->beb_rsvd_pebs += pebs;
+ if (pebs > 0)
+ ubi_msg("reserve more %d PEBs", pebs);
+ }
+ for (i = 0; i < reserved_pebs; i++)
+ new_mapping[i] = vol->eba_tbl[i];
+ kfree(vol->eba_tbl);
+ vol->eba_tbl = new_mapping;
+ spin_unlock(&ubi->volumes_lock);
+ }
+
+ vol->reserved_pebs = reserved_pebs;
+ if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
+ vol->used_ebs = reserved_pebs;
+ vol->last_eb_bytes = vol->usable_leb_size;
+ vol->used_bytes = vol->used_ebs * vol->usable_leb_size;
+ }
+
+ paranoid_check_volumes(ubi);
+ return 0;
+
+out_acc:
+ if (pebs > 0) {
+ spin_lock(&ubi->volumes_lock);
+ ubi->rsvd_pebs -= pebs;
+ ubi->avail_pebs += pebs;
+ spin_unlock(&ubi->volumes_lock);
+ }
+out_free:
+ kfree(new_mapping);
+ return err;
+}
+
+/**
+ * ubi_add_volume - add volume.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ *
+ * This function adds an existin volume and initializes all its data
+ * structures. Returnes zero in case of success and a negative error code in
+ * case of failure.
+ */
+int ubi_add_volume(struct ubi_device *ubi, int vol_id)
+{
+ int err;
+ struct ubi_volume *vol = ubi->volumes[vol_id];
+
+ dbg_msg("add volume %d", vol_id);
+ ubi_dbg_dump_vol_info(vol);
+ ubi_assert(vol);
+
+ /* Register character device for the volume */
+ cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
+ vol->cdev.owner = THIS_MODULE;
+ err = cdev_add(&vol->cdev, MKDEV(ubi->major, vol->vol_id + 1), 1);
+ if (err) {
+ ubi_err("cannot add character device for volume %d", vol_id);
+ return err;
+ }
+
+ err = ubi_create_gluebi(ubi, vol);
+ if (err)
+ goto out_cdev;
+
+ vol->dev.release = vol_release;
+ vol->dev.parent = &ubi->dev;
+ vol->dev.devt = MKDEV(ubi->major, vol->vol_id + 1);
+ vol->dev.class = ubi_class;
+ sprintf(&vol->dev.bus_id[0], "%s_%d", ubi->ubi_name, vol->vol_id);
+ err = device_register(&vol->dev);
+ if (err)
+ goto out_gluebi;
+
+ err = volume_sysfs_init(ubi, vol);
+ if (err) {
+ cdev_del(&vol->cdev);
+ err = ubi_destroy_gluebi(vol);
+ volume_sysfs_close(vol);
+ return err;
+ }
+
+ paranoid_check_volumes(ubi);
+ return 0;
+
+out_gluebi:
+ err = ubi_destroy_gluebi(vol);
+out_cdev:
+ cdev_del(&vol->cdev);
+ return err;
+}
+
+/**
+ * ubi_free_volume - free volume.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ *
+ * This function frees all resources for volume @vol_id but does not remove it.
+ * Used only when the UBI device is detached.
+ */
+void ubi_free_volume(struct ubi_device *ubi, int vol_id)
+{
+ int err;
+ struct ubi_volume *vol = ubi->volumes[vol_id];
+
+ dbg_msg("free volume %d", vol_id);
+ ubi_assert(vol);
+
+ vol->removed = 1;
+ err = ubi_destroy_gluebi(vol);
+ ubi->volumes[vol_id] = NULL;
+ cdev_del(&vol->cdev);
+ volume_sysfs_close(vol);
+}
+
+#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
+
+/**
+ * paranoid_check_volume - check volume information.
+ * @ubi: UBI device description object
+ * @vol_id: volume ID
+ */
+static void paranoid_check_volume(const struct ubi_device *ubi, int vol_id)
+{
+ int idx = vol_id2idx(ubi, vol_id);
+ int reserved_pebs, alignment, data_pad, vol_type, name_len, upd_marker;
+ const struct ubi_volume *vol = ubi->volumes[idx];
+ long long n;
+ const char *name;
+
+ reserved_pebs = ubi32_to_cpu(ubi->vtbl[vol_id].reserved_pebs);
+
+ if (!vol) {
+ if (reserved_pebs) {
+ ubi_err("no volume info, but volume exists");
+ goto fail;
+ }
+ return;
+ }
+
+ if (unlikely(vol->reserved_pebs < 0 || vol->alignment < 0 ||
+ vol->data_pad < 0 || vol->name_len < 0)) {
+ ubi_err("negative values");
+ goto fail;
+ }
+ if (unlikely(vol->alignment > ubi->leb_size ||
+ vol->alignment == 0)) {
+ ubi_err("bad alignment");
+ goto fail;
+ }
+
+ n = vol->alignment % ubi->min_io_size;
+ if (vol->alignment != 1 && unlikely(n)) {
+ ubi_err("alignment is not multiple of min I/O unit");
+ goto fail;
+ }
+
+ n = ubi->leb_size % vol->alignment;
+ if (unlikely(vol->data_pad != n)) {
+ ubi_err("bad data_pad, has to be %lld", n);
+ goto fail;
+ }
+
+ if (unlikely(vol->vol_type != UBI_DYNAMIC_VOLUME &&
+ vol->vol_type != UBI_STATIC_VOLUME)) {
+ ubi_err("bad vol_type");
+ goto fail;
+ }
+
+ if (unlikely(vol->upd_marker != 0 && vol->upd_marker != 1)) {
+ ubi_err("bad upd_marker");
+ goto fail;
+ }
+
+ if (unlikely(vol->upd_marker && vol->corrupted)) {
+ dbg_err("update marker and corrupted simultaneously");
+ goto fail;
+ }
+
+ if (unlikely(vol->reserved_pebs > ubi->good_peb_count)) {
+ ubi_err("too large reserved_pebs");
+ goto fail;
+ }
+
+ n = ubi->leb_size - vol->data_pad;
+ if (unlikely(vol->usable_leb_size != ubi->leb_size - vol->data_pad)) {
+ ubi_err("bad usable_leb_size, has to be %lld", n);
+ goto fail;
+ }
+
+ if (unlikely(vol->name_len > UBI_VOL_NAME_MAX)) {
+ ubi_err("too long volume name, max is %d", UBI_VOL_NAME_MAX);
+ goto fail;
+ }
+
+ if (unlikely(!vol->name)) {
+ ubi_err("NULL volume name");
+ goto fail;
+ }
+
+ n = strnlen(vol->name, vol->name_len + 1);
+ if (unlikely(n != vol->name_len)) {
+ ubi_err("bad name_len %lld", n);
+ goto fail;
+ }
+
+ n = vol->used_ebs * vol->usable_leb_size;
+ if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
+ if (unlikely(vol->corrupted != 0)) {
+ ubi_err("corrupted dynamic volume");
+ goto fail;
+ }
+ if (unlikely(vol->used_ebs != vol->reserved_pebs)) {
+ ubi_err("bad used_ebs");
+ goto fail;
+ }
+ if (unlikely(vol->last_eb_bytes != vol->usable_leb_size)) {
+ ubi_err("bad last_eb_bytes");
+ goto fail;
+ }
+ if (unlikely(vol->used_bytes != n)) {
+ ubi_err("bad used_bytes");
+ goto fail;
+ }
+ } else {
+ if (unlikely(vol->corrupted != 0 && vol->corrupted != 1)) {
+ ubi_err("bad corrupted");
+ goto fail;
+ }
+ if (unlikely(vol->used_ebs < 0 ||
+ vol->used_ebs > vol->reserved_pebs)) {
+ ubi_err("bad used_ebs");
+ goto fail;
+ }
+ if (unlikely(vol->last_eb_bytes < 0 ||
+ vol->last_eb_bytes > vol->usable_leb_size)) {
+ ubi_err("bad last_eb_bytes");
+ goto fail;
+ }
+ if (unlikely(vol->used_bytes < 0 || vol->used_bytes > n ||
+ vol->used_bytes < n - vol->usable_leb_size)) {
+ ubi_err("bad used_bytes");
+ goto fail;
+ }
+ }
+
+ alignment = ubi32_to_cpu(ubi->vtbl[vol_id].alignment);
+ data_pad = ubi32_to_cpu(ubi->vtbl[vol_id].data_pad);
+ name_len = ubi16_to_cpu(ubi->vtbl[vol_id].name_len);
+ upd_marker = ubi->vtbl[vol_id].upd_marker;
+ name = &ubi->vtbl[vol_id].name[0];
+ if (ubi->vtbl[vol_id].vol_type == UBI_VID_DYNAMIC)
+ vol_type = UBI_DYNAMIC_VOLUME;
+ else
+ vol_type = UBI_STATIC_VOLUME;
+
+ if (alignment != vol->alignment || data_pad != vol->data_pad ||
+ upd_marker != vol->upd_marker || vol_type != vol->vol_type ||
+ name_len!= vol->name_len || strncmp(name, vol->name, name_len)) {
+ ubi_err("volume info is different");
+ goto fail;
+ }
+
+ return;
+
+fail:
+ ubi_err("paranoid check failed");
+ ubi_dbg_dump_vol_info(vol);
+ ubi_dbg_dump_vtbl_record(&ubi->vtbl[vol_id], vol_id);
+ BUG();
+}
+
+/**
+ * paranoid_check_volumes - check information about all volumes.
+ * @ubi: UBI device description object
+ */
+static void paranoid_check_volumes(struct ubi_device *ubi)
+{
+ int i;
+
+ mutex_lock(&ubi->vtbl_mutex);
+ spin_lock(&ubi->volumes_lock);
+ for (i = 0; i < ubi->vtbl_slots; i++)
+ paranoid_check_volume(ubi, i);
+ spin_unlock(&ubi->volumes_lock);
+ mutex_unlock(&ubi->vtbl_mutex);
+}
+#endif
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 14/20 take 4] UBI: character devices functionality
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (12 preceding siblings ...)
2007-03-23 16:44 ` [PATCH 13/20 take 4] UBI: volume management functionality Artem Bityutskiy
@ 2007-03-23 16:44 ` Artem Bityutskiy
2007-03-23 16:44 ` [PATCH 15/20 take 4] UBI: gluebi functionality Artem Bityutskiy
` (5 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:44 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 17119 bytes --]
diff -auNrp tmp-from/drivers/mtd/ubi/cdev.c tmp-to/drivers/mtd/ubi/cdev.c
--- tmp-from/drivers/mtd/ubi/cdev.c 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/cdev.c 2007-03-23 18:20:02.000000000 +0200
@@ -0,0 +1,724 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file includes implementation of UBI character device operations.
+ *
+ * There are two kinds of character devices in UBI: UBI character devices and
+ * UBI volume character devices. UBI character devices allow users to
+ * manipulate whole volumes: create, remove, and re-size them. Volume character
+ * devices provide volume I/O capabilities.
+ *
+ * Major and minor numbers are assigned dynamically to both UBI and volume
+ * character devices.
+ */
+
+#include <linux/module.h>
+#include <linux/stat.h>
+#include <linux/ioctl.h>
+#include <linux/capability.h>
+#include <mtd/ubi-user.h>
+#include <asm/uaccess.h>
+#include <asm/div64.h>
+#include "ubi.h"
+
+/*
+ * Maximum sequence numbers of UBI and volume character device IOCTLs (direct
+ * logical eraseblock erase is a debug-only feature).
+ */
+#define UBI_CDEV_IOC_MAX_SEQ 2
+#ifndef CONFIG_MTD_UBI_DEBUG_USERSPACE_IO
+#define VOL_CDEV_IOC_MAX_SEQ 1
+#else
+#define VOL_CDEV_IOC_MAX_SEQ 2
+#endif
+
+/**
+ * major_to_device - get UBI device object by character device major number.
+ * @major: major number
+ *
+ * This function returns a pointer to the UBI device object.
+ */
+static struct ubi_device *major_to_device(int major)
+{
+ int i;
+
+ for (i = 0; i < ubi_devices_cnt; i++)
+ if (ubi_devices[i] && ubi_devices[i]->major == major)
+ return ubi_devices[i];
+ BUG();
+}
+
+/**
+ * get_exclusive - get exclusive access to an UBI volume.
+ * @desc: volume descriptor
+ *
+ * This function changes UBI volume open mode to "exclusive". Returns previous
+ * mode value (positive integer) in case of success and a negative error code
+ * in case of failure.
+ */
+static int get_exclusive(struct ubi_volume_desc *desc)
+{
+ int users, err;
+ struct ubi_volume *vol = desc->vol;
+
+ spin_lock(&vol->ubi->volumes_lock);
+ users = vol->readers + vol->writers + vol->exclusive;
+ ubi_assert(users > 0);
+ if (users > 1) {
+ dbg_err("%d users for volume %d", users, vol->vol_id);
+ err = -EBUSY;
+ } else {
+ vol->readers = vol->writers = 0;
+ vol->exclusive = 1;
+ err = desc->mode;
+ desc->mode = UBI_EXCLUSIVE;
+ }
+ spin_unlock(&vol->ubi->volumes_lock);
+
+ return err;
+}
+
+/**
+ * revoke_exclusive - revoke exclusive mode.
+ * @desc: volume descriptor
+ * @mode: new mode to switch to
+ */
+static void revoke_exclusive(struct ubi_volume_desc *desc, int mode)
+{
+ struct ubi_volume *vol = desc->vol;
+
+ spin_lock(&vol->ubi->volumes_lock);
+ ubi_assert(vol->readers == 0 && vol->writers == 0);
+ ubi_assert(vol->exclusive == 1 && desc->mode == UBI_EXCLUSIVE);
+ vol->exclusive = 0;
+ if (mode == UBI_READONLY)
+ vol->readers = 1;
+ else if (mode == UBI_READWRITE)
+ vol->writers = 1;
+ else
+ vol->exclusive = 1;
+ spin_unlock(&vol->ubi->volumes_lock);
+
+ desc->mode = mode;
+}
+
+static int vol_cdev_open(struct inode *inode, struct file *file)
+{
+ struct ubi_volume_desc *desc;
+ const struct ubi_device *ubi = major_to_device(imajor(inode));
+ int vol_id = iminor(inode) - 1;
+ int mode;
+
+ if (file->f_mode & FMODE_WRITE)
+ mode = UBI_READWRITE;
+ else
+ mode = UBI_READONLY;
+
+ dbg_msg("open volume %d, mode %d", vol_id, mode);
+
+ desc = ubi_open_volume(ubi->ubi_num, vol_id, mode);
+ if (IS_ERR(desc))
+ return PTR_ERR(desc);
+
+ file->private_data = desc;
+ return 0;
+}
+
+static int vol_cdev_release(struct inode *inode, struct file *file)
+{
+ struct ubi_volume_desc *desc = file->private_data;
+ struct ubi_volume *vol = desc->vol;
+
+ dbg_msg("release volume %d, mode %d", vol->vol_id, desc->mode);
+
+ if (vol->updating) {
+ ubi_warn("update of volume %d not finished, volume is damaged",
+ vol->vol_id);
+ vol->updating = 0;
+ kfree(vol->upd_buf);
+ }
+
+ ubi_close_volume(desc);
+ return 0;
+}
+
+static loff_t vol_cdev_llseek(struct file *file, loff_t offset, int origin)
+{
+ struct ubi_volume_desc *desc = file->private_data;
+ struct ubi_volume *vol = desc->vol;
+ loff_t new_offset;
+
+ if (vol->updating) {
+ /* Update is in progress, seeking is prohibited */
+ dbg_err("updating");
+ return -EBUSY;
+ }
+
+ switch (origin) {
+ case 0: /* SEEK_SET */
+ new_offset = offset;
+ break;
+ case 1: /* SEEK_CUR */
+ new_offset = file->f_pos + offset;
+ break;
+ case 2: /* SEEK_END */
+ new_offset = vol->used_bytes + offset;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (new_offset < 0 || new_offset > vol->used_bytes) {
+ dbg_err("bad seek %lld", new_offset);
+ return -EINVAL;
+ }
+
+ dbg_msg("seek volume %d, offset %lld, origin %d, new offset %lld",
+ vol->vol_id, offset, origin, new_offset);
+
+ file->f_pos = new_offset;
+ return new_offset;
+}
+
+static ssize_t vol_cdev_read(struct file *file, __user char *buf, size_t count,
+ loff_t *offp)
+{
+ struct ubi_volume_desc *desc = file->private_data;
+ struct ubi_volume *vol = desc->vol;
+ struct ubi_device *ubi = vol->ubi;
+ int err, lnum, off, len, vol_id = desc->vol->vol_id, tbuf_size;
+ size_t count_save = count;
+ void *tbuf;
+ uint64_t tmp;
+
+ dbg_msg("read %zd bytes from offset %lld of volume %d",
+ count, *offp, vol_id);
+
+ if (vol->updating) {
+ dbg_err("updating");
+ return -EBUSY;
+ }
+ if (vol->upd_marker) {
+ dbg_err("damaged volume, update marker is set");
+ return -EBADF;
+ }
+ if (*offp == vol->used_bytes || count == 0)
+ return 0;
+
+ if (vol->corrupted)
+ dbg_msg("read from corrupted volume %d", vol_id);
+
+ if (*offp + count > vol->used_bytes)
+ count_save = count = vol->used_bytes - *offp;
+
+ tbuf_size = vol->usable_leb_size;
+ if (count < tbuf_size)
+ tbuf_size = ubi_align_up(count, ubi->min_io_size);
+ tbuf = kmalloc(tbuf_size, GFP_KERNEL);
+ if (!tbuf)
+ return -ENOMEM;
+
+ len = count > tbuf_size ? tbuf_size : count;
+
+ tmp = *offp;
+ off = do_div(tmp, vol->usable_leb_size);
+ lnum = tmp;
+
+ do {
+ cond_resched();
+
+ if (off + len >= vol->usable_leb_size)
+ len = vol->usable_leb_size - off;
+
+ err = ubi_eba_read_leb(ubi, vol_id, lnum, tbuf, off, len, 0);
+ if (unlikely(err))
+ break;
+
+ off += len;
+ if (off == vol->usable_leb_size) {
+ lnum += 1;
+ off -= vol->usable_leb_size;
+ }
+
+ count -= len;
+ *offp += len;
+
+ err = copy_to_user(buf, tbuf, len);
+ if (unlikely(err)) {
+ err = -EFAULT;
+ break;
+ }
+
+ buf += len;
+ len = count > tbuf_size ? tbuf_size : count;
+ } while (count);
+
+ kfree(tbuf);
+ return err ? err : count_save - count;
+}
+
+#ifdef CONFIG_MTD_UBI_DEBUG_USERSPACE_IO
+
+/*
+ * This function allows to directly write to dynamic UBI volumes, without
+ * issuing the volume update operation. Available only as a debugging feature.
+ * Very useful for testing UBI.
+ */
+static ssize_t vol_cdev_direct_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *offp)
+{
+ struct ubi_volume_desc *desc = file->private_data;
+ struct ubi_volume *vol = desc->vol;
+ struct ubi_device *ubi = vol->ubi;
+ int lnum, off, len, tbuf_size, vol_id = vol->vol_id, err = 0;
+ size_t count_save = count;
+ char *tbuf;
+ uint64_t tmp;
+
+ dbg_msg("requested: write %zd bytes to offset %lld of volume %u",
+ count, *offp, desc->vol->vol_id);
+
+ if (vol->vol_type == UBI_STATIC_VOLUME)
+ return -EROFS;
+
+ tmp = *offp;
+ off = do_div(tmp, vol->usable_leb_size);
+ lnum = tmp;
+
+ if (off % ubi->min_io_size) {
+ dbg_err("unaligned position");
+ return -EINVAL;
+ }
+
+ if (*offp + count > vol->used_bytes)
+ count_save = count = vol->used_bytes - *offp;
+
+ /* We can write only in fractions of the minimum I/O unit */
+ if (count % ubi->min_io_size) {
+ dbg_err("unaligned write length");
+ return -EINVAL;
+ }
+
+ tbuf_size = vol->usable_leb_size;
+ if (count < tbuf_size)
+ tbuf_size = ubi_align_up(count, ubi->min_io_size);
+ tbuf = kmalloc(tbuf_size, GFP_KERNEL);
+ if (!tbuf)
+ return -ENOMEM;
+
+ len = count > tbuf_size ? tbuf_size : count;
+
+ while (count) {
+ cond_resched();
+
+ if (off + len >= vol->usable_leb_size)
+ len = vol->usable_leb_size - off;
+
+ err = copy_from_user(tbuf, buf, len);
+ if (err) {
+ err = -EFAULT;
+ break;
+ }
+
+ err = ubi_eba_write_leb(ubi, vol_id, lnum, tbuf, off, len,
+ UBI_DATA_UNKNOWN);
+ if (unlikely(err))
+ break;
+
+ off += len;
+ if (off == vol->usable_leb_size) {
+ lnum += 1;
+ off -= vol->usable_leb_size;
+ }
+
+ count -= len;
+ *offp += len;
+ buf += len;
+ len = count > tbuf_size ? tbuf_size : count;
+ }
+
+ kfree(tbuf);
+ return err ? err : count_save - count;
+}
+
+#else
+#define vol_cdev_direct_write(file, buf, count, offp) -EPERM
+#endif /* CONFIG_MTD_UBI_DEBUG_USERSPACE_IO */
+
+static ssize_t vol_cdev_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *offp)
+{
+ int err = 0;
+ struct ubi_volume_desc *desc = file->private_data;
+ struct ubi_volume *vol = desc->vol;
+ struct ubi_device *ubi = vol->ubi;
+
+ if (!vol->updating)
+ return vol_cdev_direct_write(file, buf, count, offp);
+
+ err = ubi_more_update_data(ubi, vol->vol_id, buf, count);
+ if (err < 0) {
+ ubi_err("cannot write %zd bytes of update data", count);
+ return err;
+ }
+
+ if (err) {
+ /*
+ * Update is finished, @err contains number of actually written
+ * bytes now.
+ */
+ count = err;
+
+ err = ubi_check_volume(ubi, vol->vol_id);
+ if (err < 0)
+ return err;
+
+ if (err) {
+ ubi_warn("volume %d on UBI device %d is corrupted",
+ vol->vol_id, ubi->ubi_num);
+ vol->corrupted = 1;
+ }
+ vol->checked = 1;
+ revoke_exclusive(desc, UBI_READWRITE);
+ }
+
+ *offp += count;
+ return count;
+}
+
+static int vol_cdev_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ int err = 0;
+ struct ubi_volume_desc *desc = file->private_data;
+ struct ubi_volume *vol = desc->vol;
+ struct ubi_device *ubi = vol->ubi;
+ void __user *argp = (void __user *)arg;
+
+ if (_IOC_NR(cmd) > VOL_CDEV_IOC_MAX_SEQ ||
+ _IOC_TYPE(cmd) != UBI_VOL_IOC_MAGIC)
+ return -ENOTTY;
+
+ if (_IOC_DIR(cmd) && _IOC_READ)
+ err = !access_ok(VERIFY_WRITE, argp, _IOC_SIZE(cmd));
+ else if (_IOC_DIR(cmd) && _IOC_WRITE)
+ err = !access_ok(VERIFY_READ, argp, _IOC_SIZE(cmd));
+ if (err)
+ return -EFAULT;
+
+ switch (cmd) {
+
+ /* Volume update command */
+ case UBI_IOCVOLUP:
+ {
+ int64_t bytes, rsvd_bytes;
+
+ if (!capable(CAP_SYS_RESOURCE)) {
+ err = -EPERM;
+ break;
+ }
+
+ err = copy_from_user(&bytes, argp, sizeof(int64_t));
+ if (err) {
+ err = -EFAULT;
+ break;
+ }
+
+ if (desc->mode == UBI_READONLY) {
+ err = -EROFS;
+ break;
+ }
+
+ rsvd_bytes = vol->reserved_pebs * (ubi->leb_size-vol->data_pad);
+ if (bytes < 0 || bytes > rsvd_bytes) {
+ err = -EINVAL;
+ break;
+ }
+
+ err = get_exclusive(desc);
+ if (err < 0)
+ break;
+
+ err = ubi_start_update(ubi, vol->vol_id, bytes);
+ if (bytes == 0)
+ revoke_exclusive(desc, UBI_READWRITE);
+
+ file->f_pos = 0;
+ break;
+ }
+
+#ifdef CONFIG_MTD_UBI_DEBUG_USERSPACE_IO
+ /* Logical eraseblock erasure command */
+ case UBI_IOCEBER:
+ {
+ int32_t lnum;
+
+ err = __get_user(lnum, (__user int32_t *)argp);
+ if (err) {
+ err = -EFAULT;
+ break;
+ }
+
+ if (desc->mode == UBI_READONLY) {
+ err = -EROFS;
+ break;
+ }
+
+ if (lnum < 0 || lnum >= vol->reserved_pebs) {
+ err = -EINVAL;
+ break;
+ }
+
+ if (vol->vol_type != UBI_DYNAMIC_VOLUME) {
+ err = -EROFS;
+ break;
+ }
+
+ dbg_msg("erase LEB %d:%d", vol->vol_id, lnum);
+ err = ubi_eba_unmap_leb(ubi, vol->vol_id, lnum);
+ if (err)
+ break;
+
+ err = ubi_wl_flush(ubi);
+ break;
+ }
+#endif
+
+ default:
+ err = -ENOTTY;
+ break;
+ }
+
+ return err;
+}
+
+/**
+ * verify_mkvol_req - verify volume creation request.
+ * @ubi: UBI device description object
+ * @req: the request to check
+ *
+ * This function zero if the request is correct, and %-EINVAL if not.
+ */
+static int verify_mkvol_req(const struct ubi_device *ubi,
+ const struct ubi_mkvol_req *req)
+{
+ int n;
+
+ if (req->bytes < 0 || req->alignment < 0 || req->vol_type < 0 ||
+ req->name_len < 0)
+ goto bad;
+
+ if ((req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots) &&
+ req->vol_id != UBI_VOL_NUM_AUTO)
+ goto bad;
+
+ if (req->alignment == 0)
+ goto bad;
+
+ if (req->bytes == 0)
+ goto bad;
+
+ if (req->vol_type != UBI_DYNAMIC_VOLUME &&
+ req->vol_type != UBI_STATIC_VOLUME)
+ goto bad;
+
+ if (req->alignment > ubi->leb_size)
+ goto bad;
+
+ n = req->alignment % ubi->min_io_size;
+ if (req->alignment != 1 && n)
+ goto bad;
+
+ if (req->name_len > UBI_VOL_NAME_MAX)
+ goto bad;
+
+ return 0;
+
+bad:
+ dbg_err("bad volume creation request");
+ ubi_dbg_dump_mkvol_req(req);
+ return -EINVAL;
+}
+
+/**
+ * verify_rsvol_req - verify volume re-size request.
+ * @ubi: UBI device description object
+ * @req: the request to check
+ *
+ * This function returns zero if the request is correct, and %-EINVAL if not.
+ */
+static int verify_rsvol_req(const struct ubi_device *ubi,
+ const struct ubi_rsvol_req *req)
+{
+ if (req->bytes <= 0)
+ return -EINVAL;
+
+ if (req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int ubi_cdev_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ int err = 0;
+ struct ubi_device *ubi;
+ struct ubi_volume_desc *desc;
+ void __user *argp = (void __user *)arg;
+
+ if (_IOC_NR(cmd) > UBI_CDEV_IOC_MAX_SEQ ||
+ _IOC_TYPE(cmd) != UBI_IOC_MAGIC)
+ return -ENOTTY;
+
+ if (_IOC_DIR(cmd) && _IOC_READ)
+ err = !access_ok(VERIFY_WRITE, argp, _IOC_SIZE(cmd));
+ else if (_IOC_DIR(cmd) && _IOC_WRITE)
+ err = !access_ok(VERIFY_READ, argp, _IOC_SIZE(cmd));
+ if (err)
+ return -EFAULT;
+
+ if (!capable(CAP_SYS_RESOURCE))
+ return -EPERM;
+
+ ubi = major_to_device(imajor(inode));
+ if (IS_ERR(ubi))
+ return PTR_ERR(ubi);
+
+ switch (cmd) {
+ /* Create volume command */
+ case UBI_IOCMKVOL:
+ {
+ struct ubi_mkvol_req req;
+
+ dbg_msg("create volume");
+ err = __copy_from_user(&req, argp,
+ sizeof(struct ubi_mkvol_req));
+ if (err) {
+ err = -EFAULT;
+ break;
+ }
+
+ err = verify_mkvol_req(ubi, &req);
+ if (err)
+ break;
+
+ req.name[req.name_len] = '\0';
+
+ err = ubi_create_volume(ubi, &req);
+ if (err)
+ break;
+
+ err = __put_user(req.vol_id, (__user int32_t *)argp);
+ if (err)
+ err = -EFAULT;
+
+ break;
+ }
+
+ /* Remove volume command */
+ case UBI_IOCRMVOL:
+ {
+ int vol_id;
+
+ dbg_msg("remove volume");
+ err = __get_user(vol_id, (__user int32_t *)argp);
+ if (err) {
+ err = -EFAULT;
+ break;
+ }
+
+ desc = ubi_open_volume(ubi->ubi_num, vol_id, UBI_EXCLUSIVE);
+ if (IS_ERR(desc)) {
+ err = PTR_ERR(desc);
+ break;
+ }
+
+ err = ubi_remove_volume(desc);
+ if (err)
+ ubi_close_volume(desc);
+
+ break;
+ }
+
+ /* Re-size volume command */
+ case UBI_IOCRSVOL:
+ {
+ int pebs;
+ uint64_t tmp;
+ struct ubi_rsvol_req req;
+
+ dbg_msg("re-size volume");
+ err = __copy_from_user(&req, argp,
+ sizeof(struct ubi_rsvol_req));
+ if (err) {
+ err = -EFAULT;
+ break;
+ }
+
+ err = verify_rsvol_req(ubi, &req);
+ if (err)
+ break;
+
+ desc = ubi_open_volume(ubi->ubi_num, req.vol_id, UBI_EXCLUSIVE);
+ if (IS_ERR(desc)) {
+ err = PTR_ERR(desc);
+ break;
+ }
+
+ tmp = req.bytes;
+ pebs = !!do_div(tmp, desc->vol->usable_leb_size);
+ pebs += tmp;
+
+dbg_msg("desc %p", desc);
+dbg_msg("desc->vol %p", desc->vol);
+dbg_msg("desc->vol->vol_id %d", desc->vol->vol_id);
+dbg_msg("desc->vol->ubi %d", desc->vol->ubi);
+ err = ubi_resize_volume(desc, pebs);
+ ubi_close_volume(desc);
+ break;
+ }
+
+ default:
+ err = -ENOTTY;
+ break;
+ }
+
+ return err;
+}
+
+/* UBI character device operations */
+struct file_operations ubi_cdev_operations = {
+ .owner = THIS_MODULE,
+ .ioctl = ubi_cdev_ioctl,
+ .llseek = no_llseek
+};
+
+/* UBI volume character device operations */
+struct file_operations ubi_vol_cdev_operations = {
+ .owner = THIS_MODULE,
+ .open = vol_cdev_open,
+ .release = vol_cdev_release,
+ .llseek = vol_cdev_llseek,
+ .read = vol_cdev_read,
+ .write = vol_cdev_write,
+ .ioctl = vol_cdev_ioctl
+};
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 15/20 take 4] UBI: gluebi functionality
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (13 preceding siblings ...)
2007-03-23 16:44 ` [PATCH 14/20 take 4] UBI: character devices functionality Artem Bityutskiy
@ 2007-03-23 16:44 ` Artem Bityutskiy
2007-03-23 16:44 ` [PATCH 16/20 take 4] UBI: misc stuff Artem Bityutskiy
` (4 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:44 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 9836 bytes --]
diff -auNrp tmp-from/drivers/mtd/ubi/gluebi.c tmp-to/drivers/mtd/ubi/gluebi.c
--- tmp-from/drivers/mtd/ubi/gluebi.c 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/gluebi.c 2007-03-23 18:20:02.000000000 +0200
@@ -0,0 +1,337 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём), Joern Engel
+ */
+
+/*
+ * This file includes implementation of fake MTD devices for each UBI volume.
+ * This sounds strange, but it is in fact quite useful to make MTD-oriented
+ * software (including all the legacy software) to work on top of UBI.
+ *
+ * Gluebi emulates MTD devices of "MTD_UBIVOLUME" type. Their minimal I/O unit
+ * size (mtd->writesize) is equivalent to the UBI minimal I/O unit. The
+ * eraseblock size is equivalent to the logical eraseblock size of the volume.
+ */
+
+#include <asm/div64.h>
+#include "ubi.h"
+
+/**
+ * gluebi_get_device - get MTD device reference.
+ * @mtd: the MTD device description object
+ *
+ * This function is called every time the MTD device is being opened and
+ * implements the MTD get_device() operation. Returns zero in case of success
+ * and a negative error code in case of failure.
+ */
+static int gluebi_get_device(struct mtd_info *mtd)
+{
+ struct ubi_volume *vol;
+
+ vol = container_of(mtd, struct ubi_volume, gluebi_mtd);
+
+ /*
+ * We do not introduce locks for gluebi reference count because the
+ * get_device()/put_device() calls are already serialized at MTD.
+ */
+ if (vol->gluebi_refcount > 0) {
+ /*
+ * The MTD device is already referenced and this is just one
+ * more reference. MTD allows many users to open the same
+ * volume simultaneously and do not distinguish between
+ * readers/writers/exclusive openers as UBI does. So we do not
+ * open the UBI volume again - just increase the reference
+ * counter and return.
+ */
+ vol->gluebi_refcount += 1;
+ return 0;
+ }
+
+ /*
+ * This is the first reference to this UBI volume via the MTD device
+ * interface. Open the corresponding volume in read-write mode.
+ */
+ vol->gluebi_desc = ubi_open_volume(vol->ubi->ubi_num, vol->vol_id,
+ UBI_READWRITE);
+ if (IS_ERR(vol->gluebi_desc))
+ return PTR_ERR(vol->gluebi_desc);
+ vol->gluebi_refcount += 1;
+ return 0;
+}
+
+/**
+ * gluebi_put_device - put MTD device reference.
+ * @mtd: the MTD device description object
+ *
+ * This function is called every time the MTD device is being put. Returns
+ * zero in case of success and a negative error code in case of failure.
+ */
+static void gluebi_put_device(struct mtd_info *mtd)
+{
+ struct ubi_volume *vol;
+
+ vol = container_of(mtd, struct ubi_volume, gluebi_mtd);
+ vol->gluebi_refcount -= 1;
+ ubi_assert(vol->gluebi_refcount >= 0);
+ if (vol->gluebi_refcount == 0)
+ ubi_close_volume(vol->gluebi_desc);
+}
+
+/**
+ * gluebi_read - read operation of emulated MTD devices.
+ * @mtd: MTD device description object
+ * @from: absolute offset from where to read
+ * @len: how many bytes to read
+ * @retlen: count of read bytes is returned here
+ * @buf: buffer to store the read data
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int gluebi_read(struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, unsigned char *buf)
+{
+ int err = 0, lnum, offs, total_read;
+ struct ubi_volume *vol;
+ struct ubi_device *ubi;
+ uint64_t tmp = from;
+
+ dbg_msg("read %zd bytes from offset %lld", len, from);
+
+ if (unlikely(len < 0 || from < 0 || from + len > mtd->size))
+ return -EINVAL;
+
+ vol = container_of(mtd, struct ubi_volume, gluebi_mtd);
+ ubi = vol->ubi;
+
+ offs = do_div(tmp, mtd->erasesize);
+ lnum = tmp;
+
+ total_read = len;
+ while (total_read) {
+ size_t to_read = mtd->erasesize - offs;
+
+ if (to_read > total_read)
+ to_read = total_read;
+
+ err = ubi_eba_read_leb(ubi, vol->vol_id, lnum, buf, offs,
+ to_read, 0);
+ if (unlikely(err))
+ break;
+
+ lnum += 1;
+ offs = 0;
+ total_read -= to_read;
+ buf += to_read;
+ }
+
+ *retlen = len - total_read;
+ return err;
+}
+
+/**
+ * gluebi_write - write operation of emulated MTD devices.
+ * @mtd: MTD device description object
+ * @to: absolute offset where to write
+ * @len: how many bytes to write
+ * @retlen: count of written bytes is returned here
+ * @buf: buffer with data to write
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int gluebi_write(struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, const u_char *buf)
+{
+ int err = 0, lnum, offs, total_written;
+ struct ubi_volume *vol;
+ struct ubi_device *ubi;
+ uint64_t tmp = to;
+
+ dbg_msg("write %zd bytes to offset %lld", len, to);
+
+ if (unlikely(len < 0 || to < 0 || len + to > mtd->size))
+ return -EINVAL;
+
+ vol = container_of(mtd, struct ubi_volume, gluebi_mtd);
+ ubi = vol->ubi;
+
+ if (unlikely(ubi->ro_mode))
+ return -EROFS;
+
+ offs = do_div(tmp, mtd->erasesize);
+ lnum = tmp;
+
+ if (unlikely(len % mtd->writesize || offs % mtd->writesize))
+ return -EINVAL;
+
+ total_written = len;
+ while (total_written) {
+ size_t to_write = mtd->erasesize - offs;
+
+ if (to_write > total_written)
+ to_write = total_written;
+
+ err = ubi_eba_write_leb(ubi, vol->vol_id, lnum, buf, offs,
+ to_write, UBI_DATA_UNKNOWN);
+ if (unlikely(err))
+ break;
+
+ lnum += 1;
+ offs = 0;
+ total_written -= to_write;
+ buf += to_write;
+ }
+
+ *retlen = len - total_written;
+ return err;
+}
+
+/**
+ * gluebi_erase - erase operation of emulated MTD devices.
+ * @mtd: the MTD device description object
+ * @instr: the erase operation description
+ *
+ * This function calls the erase callback when finishes. Returns zero in case
+ * of success and a negative error code in case of failure.
+ */
+static int gluebi_erase(struct mtd_info *mtd, struct erase_info *instr)
+{
+ int err, i, lnum, count;
+ struct ubi_volume *vol;
+ struct ubi_device *ubi;
+
+ dbg_msg("erase %u bytes at offset %u", instr->len, instr->addr);
+
+ if (unlikely(instr->addr < 0 ||
+ instr->addr > mtd->size - mtd->erasesize))
+ return -EINVAL;
+
+ if (unlikely(instr->len < 0 ||
+ instr->addr + instr->len > mtd->size))
+ return -EINVAL;
+
+ if (unlikely(instr->addr % mtd->writesize ||
+ instr->len % mtd->writesize))
+ return -EINVAL;
+
+ lnum = instr->addr / mtd->erasesize;
+ count = instr->len / mtd->erasesize;
+
+ vol = container_of(mtd, struct ubi_volume, gluebi_mtd);
+ ubi = vol->ubi;
+
+ if (unlikely(ubi->ro_mode))
+ return -EROFS;
+
+ for (i = 0; i < count; i++) {
+ err = ubi_eba_unmap_leb(ubi, vol->vol_id, lnum + i);
+ if (unlikely(err))
+ goto out_err;
+ }
+
+ /*
+ * MTD erase operations are synchronous, so we have to make sure the
+ * physical eraseblock is wiped out.
+ */
+ err = ubi_wl_flush(ubi);
+ if (unlikely(err))
+ goto out_err;
+
+ instr->state = MTD_ERASE_DONE;
+ mtd_erase_callback(instr);
+ return 0;
+
+out_err:
+ instr->state = MTD_ERASE_FAILED;
+ instr->fail_addr = lnum * mtd->erasesize;
+ return err;
+}
+
+/**
+ * ubi_create_gluebi - initialize gluebi for an UBI volume.
+ * @ubi: UBI device description object
+ * @vol: volume description object
+ *
+ * This function is called when an UBI volume is created in order to create
+ * corresponding fake MTD device. Returns zero in case of success and a
+ * negative error code in case of failure.
+ */
+int ubi_create_gluebi(struct ubi_device *ubi, struct ubi_volume *vol)
+{
+ int err;
+ struct mtd_info *mtd = &vol->gluebi_mtd;
+
+ mtd->name = kmemdup(vol->name, vol->name_len + 1, GFP_KERNEL);
+ if (!mtd->name)
+ return -ENOMEM;
+
+ mtd->type = MTD_UBIVOLUME;
+ if (!ubi->ro_mode)
+ mtd->flags = MTD_WRITEABLE;
+ mtd->writesize = ubi->min_io_size;
+ mtd->owner = THIS_MODULE;
+ mtd->size = vol->usable_leb_size * vol->reserved_pebs;
+ mtd->erasesize = vol->usable_leb_size;
+ mtd->read = gluebi_read;
+ mtd->write = gluebi_write;
+ mtd->erase = gluebi_erase;
+ mtd->get_device = gluebi_get_device;
+ mtd->put_device = gluebi_put_device;
+
+ if (add_mtd_device(mtd)) {
+ ubi_err("cannot not add MTD device\n");
+
+ /*
+ * Unfortunately, add_mtd_device() does not return sane error
+ * code. So, let's name it -ENOMEM;
+ */
+ err = -ENOMEM;
+ goto out_free;
+ }
+
+ dbg_msg("added mtd%d (\"%s\"), size %u, EB size %u",
+ mtd->index, mtd->name, mtd->size, mtd->erasesize);
+
+ return 0;
+
+out_free:
+ kfree(mtd->name);
+ return err;
+}
+
+/**
+ * ubi_destroy_gluebi - close gluebi for an UBI volume.
+ * @vol: volume description object
+ *
+ * This function is called when an UBI volume is removed in order to remove
+ * corresponding fake MTD device. Returns zero in case of success and a
+ * negative error code in case of failure.
+ */
+int ubi_destroy_gluebi(struct ubi_volume *vol)
+{
+ int err;
+ struct mtd_info *mtd = &vol->gluebi_mtd;
+
+ dbg_msg("remove mtd%d", mtd->index);
+ err = del_mtd_device(mtd);
+ if (err)
+ return err;
+ kfree(mtd->name);
+ return 0;
+}
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 16/20 take 4] UBI: misc stuff
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (14 preceding siblings ...)
2007-03-23 16:44 ` [PATCH 15/20 take 4] UBI: gluebi functionality Artem Bityutskiy
@ 2007-03-23 16:44 ` Artem Bityutskiy
2007-03-23 16:44 ` [PATCH 17/20 take 4] UBI: debugging stuff Artem Bityutskiy
` (3 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:44 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 3475 bytes --]
diff -auNrp tmp-from/drivers/mtd/ubi/misc.c tmp-to/drivers/mtd/ubi/misc.c
--- tmp-from/drivers/mtd/ubi/misc.c 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/misc.c 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,105 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/* Here we keep miscellaneous functions which are used all over the UBI code */
+
+#include "ubi.h"
+
+/**
+ * calc_data_len - calculate how much real data is stored in a buffer.
+ * @ubi: UBI device description object
+ * @buf: a buffer with the contents of the physical eraseblock
+ * @length: the buffer length
+ *
+ * This function calculates how much "real data" is stored in @buf and returnes
+ * the length. Continuous 0xFF bytes at the end of the buffer are not
+ * considered as "real data".
+ */
+int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf,
+ int length)
+{
+ int i;
+
+ ubi_assert(length % ubi->min_io_size == 0);
+
+ for (i = length - 1; i >= 0; i--)
+ if (((const uint8_t *)buf)[i] != 0xFF)
+ break;
+
+ /* The resulting length must be aligned to the minimum flash I/O size */
+ length = ubi_align_up(i + 1, ubi->min_io_size);
+ return length;
+}
+
+/**
+ * ubi_check_volume - check the contents of a static volume.
+ * @ubi: UBI device description object
+ * @vol_id: ID of the volume to check
+ *
+ * This function checks if static volume @vol_id is corrupted by fully reading
+ * it and checking data CRC. This function returns %0 if the volume is not
+ * corrupted, %1 if it is corrupted and a negative error code in case of
+ * failure. Dynamic volumes are not checked and zero is returned immediately.
+ */
+int ubi_check_volume(struct ubi_device *ubi, int vol_id)
+{
+ void *buf;
+ int err = 0, i;
+ struct ubi_volume *vol = ubi->volumes[vol_id];
+
+ if (vol->vol_type != UBI_STATIC_VOLUME)
+ return 0;
+
+ buf = kmalloc(vol->usable_leb_size, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ for (i = 0; i < vol->used_ebs; i++) {
+ int size;
+
+ if (i == vol->used_ebs - 1)
+ size = vol->last_eb_bytes;
+ else
+ size = vol->usable_leb_size;
+
+ err = ubi_eba_read_leb(ubi, vol_id, i, buf, 0, size, 1);
+ if (err) {
+ if (err == -EBADMSG)
+ err = 1;
+ break;
+ }
+ }
+
+ kfree(buf);
+ return err;
+}
+
+/**
+ * ubi_calculate_rsvd_pool - calculate how many PEBs must be reserved for bad
+ * eraseblock handling.
+ * @ubi: UBI device description object
+ */
+void ubi_calculate_reserved(struct ubi_device *ubi)
+{
+ ubi->beb_rsvd_level = ubi->good_peb_count/100;
+ ubi->beb_rsvd_level *= CONFIG_MTD_UBI_BEB_RESERVE;
+ if (ubi->beb_rsvd_level < MIN_RESEVED_PEBS)
+ ubi->beb_rsvd_level = MIN_RESEVED_PEBS;
+}
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 17/20 take 4] UBI: debugging stuff
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (15 preceding siblings ...)
2007-03-23 16:44 ` [PATCH 16/20 take 4] UBI: misc stuff Artem Bityutskiy
@ 2007-03-23 16:44 ` Artem Bityutskiy
2007-03-23 16:44 ` [PATCH 18/20 take 4] UBI: JFFS2 UBI support Artem Bityutskiy
` (2 subsequent siblings)
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:44 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 12824 bytes --]
diff -auNrp tmp-from/drivers/mtd/ubi/debug.c tmp-to/drivers/mtd/ubi/debug.c
--- tmp-from/drivers/mtd/ubi/debug.c 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/debug.c 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,224 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * Here we keep all the UBI debugging stuff which should normally be disabled
+ * and compiled-out, but it is extremely helpful when hunting bugs or doing big
+ * changes.
+ */
+
+#ifdef CONFIG_MTD_UBI_DEBUG_MSG
+
+#include "ubi.h"
+
+/**
+ * ubi_dbg_dump_ec_hdr - dump an erase counter header.
+ * @ec_hdr: the erase counter header to dump
+ */
+void ubi_dbg_dump_ec_hdr(const struct ubi_ec_hdr *ec_hdr)
+{
+ dbg_msg("erase counter header dump:");
+ dbg_msg("magic %#08x", ubi32_to_cpu(ec_hdr->magic));
+ dbg_msg("version %d", (int)ec_hdr->version);
+ dbg_msg("ec %llu", (long long)ubi64_to_cpu(ec_hdr->ec));
+ dbg_msg("vid_hdr_offset %d", ubi32_to_cpu(ec_hdr->vid_hdr_offset));
+ dbg_msg("data_offset %d", ubi32_to_cpu(ec_hdr->data_offset));
+ dbg_msg("hdr_crc %#08x", ubi32_to_cpu(ec_hdr->hdr_crc));
+ dbg_msg("erase counter header hexdump:");
+ ubi_dbg_hexdump(ec_hdr, UBI_EC_HDR_SIZE);
+}
+
+/**
+ * ubi_dbg_dump_vid_hdr - dump a volume identifier header.
+ * @vid_hdr: the volume identifier header to dump
+ */
+void ubi_dbg_dump_vid_hdr(const struct ubi_vid_hdr *vid_hdr)
+{
+ dbg_msg("volume identifier header dump:");
+ dbg_msg("magic %08x", ubi32_to_cpu(vid_hdr->magic));
+ dbg_msg("version %d", (int)vid_hdr->version);
+ dbg_msg("vol_type %d", (int)vid_hdr->vol_type);
+ dbg_msg("copy_flag %d", (int)vid_hdr->copy_flag);
+ dbg_msg("compat %d", (int)vid_hdr->compat);
+ dbg_msg("vol_id %d", ubi32_to_cpu(vid_hdr->vol_id));
+ dbg_msg("lnum %d", ubi32_to_cpu(vid_hdr->lnum));
+ dbg_msg("leb_ver %u", ubi32_to_cpu(vid_hdr->leb_ver));
+ dbg_msg("data_size %d", ubi32_to_cpu(vid_hdr->data_size));
+ dbg_msg("used_ebs %d", ubi32_to_cpu(vid_hdr->used_ebs));
+ dbg_msg("data_pad %d", ubi32_to_cpu(vid_hdr->data_pad));
+ dbg_msg("sqnum %llu",
+ (unsigned long long)ubi64_to_cpu(vid_hdr->sqnum));
+ dbg_msg("hdr_crc %08x", ubi32_to_cpu(vid_hdr->hdr_crc));
+ dbg_msg("volume identifier header hexdump:");
+}
+
+/**
+ * ubi_dbg_dump_vol_info- dump volume information.
+ * @vol: UBI volume description object
+ */
+void ubi_dbg_dump_vol_info(const struct ubi_volume *vol)
+{
+ dbg_msg("volume information dump:");
+ dbg_msg("vol_id %d", vol->vol_id);
+ dbg_msg("reserved_pebs %d", vol->reserved_pebs);
+ dbg_msg("alignment %d", vol->alignment);
+ dbg_msg("data_pad %d", vol->data_pad);
+ dbg_msg("vol_type %d", vol->vol_type);
+ dbg_msg("name_len %d", vol->name_len);
+ dbg_msg("usable_leb_size %d", vol->usable_leb_size);
+ dbg_msg("used_ebs %d", vol->used_ebs);
+ dbg_msg("used_bytes %lld", vol->used_bytes);
+ dbg_msg("last_eb_bytes %d", vol->last_eb_bytes);
+ dbg_msg("corrupted %d", vol->corrupted);
+ dbg_msg("upd_marker %d", vol->upd_marker);
+
+ if (vol->name_len <= UBI_VOL_NAME_MAX &&
+ strnlen(vol->name, vol->name_len + 1) == vol->name_len) {
+ dbg_msg("name %s", vol->name);
+ } else {
+ dbg_msg("the 1st 5 characters of the name: %c%c%c%c%c",
+ vol->name[0], vol->name[1], vol->name[2],
+ vol->name[3], vol->name[4]);
+ }
+}
+
+/**
+ * ubi_dbg_dump_vtbl_record - dump a &struct ubi_vtbl_record object.
+ * @r: the object to dump
+ * @idx: volume table index
+ */
+void ubi_dbg_dump_vtbl_record(const struct ubi_vtbl_record *r, int idx)
+{
+ int name_len = ubi16_to_cpu(r->name_len);
+
+ dbg_msg("volume table record %d dump:", idx);
+ dbg_msg("reserved_pebs %d", ubi32_to_cpu(r->reserved_pebs));
+ dbg_msg("alignment %d", ubi32_to_cpu(r->alignment));
+ dbg_msg("data_pad %d", ubi32_to_cpu(r->data_pad));
+ dbg_msg("vol_type %d", (int)r->vol_type);
+ dbg_msg("upd_marker %d", (int)r->upd_marker);
+ dbg_msg("name_len %d", name_len);
+
+ if (r->name[0] == '\0') {
+ dbg_msg("name NULL");
+ return;
+ }
+
+ if (name_len <= UBI_VOL_NAME_MAX &&
+ strnlen(&r->name[0], name_len + 1) == name_len) {
+ dbg_msg("name %s", &r->name[0]);
+ } else {
+ dbg_msg("1st 5 characters of the name: %c%c%c%c%c",
+ r->name[0], r->name[1], r->name[2], r->name[3],
+ r->name[4]);
+ }
+ dbg_msg("crc %#08x", ubi32_to_cpu(r->crc));
+}
+
+/**
+ * ubi_dbg_dump_sv - dump a &struct ubi_scan_volume object.
+ * @sv: the object to dump
+ */
+void ubi_dbg_dump_sv(const struct ubi_scan_volume *sv)
+{
+ dbg_msg("volume scanning information dump:");
+ dbg_msg("vol_id %d", sv->vol_id);
+ dbg_msg("highest_lnum %d", sv->highest_lnum);
+ dbg_msg("leb_count %d", sv->leb_count);
+ dbg_msg("compat %d", sv->compat);
+ dbg_msg("vol_type %d", sv->vol_type);
+ dbg_msg("used_ebs %d", sv->used_ebs);
+ dbg_msg("last_data_size %d", sv->last_data_size);
+ dbg_msg("data_pad %d", sv->data_pad);
+}
+
+/**
+ * ubi_dbg_dump_seb - dump a &struct ubi_scan_leb object.
+ * @seb: the object to dump
+ * @type: object type: 0 - not corrupted, 1 - corrupted
+ */
+void ubi_dbg_dump_seb(const struct ubi_scan_leb *seb, int type)
+{
+ dbg_msg("eraseblock scanning information dump:");
+ dbg_msg("ec %d", seb->ec);
+ dbg_msg("pnum %d", seb->pnum);
+ if (type == 0) {
+ dbg_msg("lnum %d", seb->lnum);
+ dbg_msg("scrub %d", seb->scrub);
+ dbg_msg("sqnum %llu", seb->sqnum);
+ dbg_msg("leb_ver %u", seb->leb_ver);
+ }
+}
+
+/**
+ * ubi_dbg_dump_mkvol_req - dump a &struct ubi_mkvol_req object.
+ * @req: the object to dump
+ */
+void ubi_dbg_dump_mkvol_req(const struct ubi_mkvol_req *req)
+{
+ char nm[17];
+
+ dbg_msg("volume creation request dump:");
+ dbg_msg("vol_id %d", req->vol_id);
+ dbg_msg("alignment %d", req->alignment);
+ dbg_msg("bytes %lld", (long long)req->bytes);
+ dbg_msg("vol_type %d", req->vol_type);
+ dbg_msg("name_len %d", req->name_len);
+
+ memcpy(nm, req->name, 16);
+ nm[16] = 0;
+ dbg_msg("the 1st 16 characters of the name: %s", nm);
+}
+
+#define BYTES_PER_LINE 32
+
+/**
+ * ubi_dbg_hexdump - dump a buffer.
+ * @ptr: the buffer to dump
+ * @size: buffer size which must be multiple of 4 bytes
+ */
+void ubi_dbg_hexdump(const void *ptr, int size)
+{
+ int i, k = 0, rows, columns;
+ const uint8_t *p = ptr;
+
+ size = ALIGN(size, 4);
+ rows = size/BYTES_PER_LINE + size % BYTES_PER_LINE;
+ for (i = 0; i < rows; i++) {
+ int j;
+
+ cond_resched();
+ columns = min(size - k, BYTES_PER_LINE) / 4;
+ if (columns == 0)
+ break;
+ printk(KERN_DEBUG "%5d: ", i * BYTES_PER_LINE);
+ for (j = 0; j < columns; j++) {
+ int n, N;
+
+ N = size - k > 4 ? 4 : size - k;
+ for (n = 0; n < N; n++)
+ printk("%02x", p[k++]);
+ printk(" ");
+ }
+ printk("\n");
+ }
+}
+
+#endif /* CONFIG_MTD_UBI_DEBUG_MSG */
diff -auNrp tmp-from/drivers/mtd/ubi/debug.h tmp-to/drivers/mtd/ubi/debug.h
--- tmp-from/drivers/mtd/ubi/debug.h 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/debug.h 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,161 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+#ifndef __UBI_DEBUG_H__
+#define __UBI_DEBUG_H__
+
+#ifdef CONFIG_MTD_UBI_DEBUG
+#include <linux/random.h>
+
+#define ubi_assert(expr) BUG_ON(!(expr))
+#define dbg_err(fmt, ...) ubi_err(fmt, ##__VA_ARGS__)
+#else
+#define ubi_assert(expr) ({})
+#define dbg_err(fmt, ...) ({})
+#endif
+
+#ifdef CONFIG_MTD_UBI_DEBUG_DISABLE_BGT
+#define DBG_DISABLE_BGT 1
+#else
+#define DBG_DISABLE_BGT 0
+#endif
+
+#ifdef CONFIG_MTD_UBI_DEBUG_MSG
+/* Generic debugging message */
+#define dbg_msg(fmt, ...) \
+ printk(KERN_DEBUG "UBI DBG: %s: " fmt "\n", __FUNCTION__, ##__VA_ARGS__)
+
+#define ubi_dbg_dump_stack() dump_stack()
+
+struct ubi_ec_hdr;
+struct ubi_vid_hdr;
+struct ubi_volume;
+struct ubi_vtbl_record;
+struct ubi_scan_volume;
+struct ubi_scan_leb;
+struct ubi_mkvol_req;
+
+void ubi_dbg_print(int type, const char *func, const char *fmt, ...);
+void ubi_dbg_dump_ec_hdr(const struct ubi_ec_hdr *ec_hdr);
+void ubi_dbg_dump_vid_hdr(const struct ubi_vid_hdr *vid_hdr);
+void ubi_dbg_dump_vol_info(const struct ubi_volume *vol);
+void ubi_dbg_dump_vtbl_record(const struct ubi_vtbl_record *r, int idx);
+void ubi_dbg_dump_sv(const struct ubi_scan_volume *sv);
+void ubi_dbg_dump_seb(const struct ubi_scan_leb *seb, int type);
+void ubi_dbg_dump_mkvol_req(const struct ubi_mkvol_req *req);
+void ubi_dbg_hexdump(const void *buf, int size);
+
+#else
+
+#define dbg_msg(fmt, ...) ({})
+#define ubi_dbg_dump_stack() ({})
+#define ubi_dbg_print(func, fmt, ...) ({})
+#define ubi_dbg_dump_ec_hdr(ec_hdr) ({})
+#define ubi_dbg_dump_vid_hdr(vid_hdr) ({})
+#define ubi_dbg_dump_vol_info(vol) ({})
+#define ubi_dbg_dump_vtbl_record(r, idx) ({})
+#define ubi_dbg_dump_sv(sv) ({})
+#define ubi_dbg_dump_seb(seb, type) ({})
+#define ubi_dbg_dump_mkvol_req(req) ({})
+#define ubi_dbg_hexdump(buf, size) ({})
+
+#endif /* CONFIG_MTD_UBI_DEBUG_MSG */
+
+#ifdef CONFIG_MTD_UBI_DEBUG_MSG_EBA
+/* Messages from the eraseblock association unit */
+#define dbg_eba(fmt, ...) \
+ printk(KERN_DEBUG "UBI DBG eba: %s: " fmt "\n", __FUNCTION__, \
+ ##__VA_ARGS__)
+#else
+#define dbg_eba(fmt, ...) ({})
+#endif
+
+#ifdef CONFIG_MTD_UBI_DEBUG_MSG_WL
+/* Messages from the wear-leveling unit */
+#define dbg_wl(fmt, ...) \
+ printk(KERN_DEBUG "UBI DBG wl: %s: " fmt "\n", __FUNCTION__, \
+ ##__VA_ARGS__)
+#else
+#define dbg_wl(fmt, ...) ({})
+#endif
+
+#ifdef CONFIG_MTD_UBI_DEBUG_MSG_IO
+/* Messages from the input/output unit */
+#define dbg_io(fmt, ...) \
+ printk(KERN_DEBUG "UBI DBG io: %s: " fmt "\n", __FUNCTION__, \
+ ##__VA_ARGS__)
+#else
+#define dbg_io(fmt, ...) ({})
+#endif
+
+#ifdef CONFIG_MTD_UBI_DEBUG_MSG_BLD
+/* Initialization and build messages */
+#define dbg_bld(fmt, ...) \
+ printk(KERN_DEBUG "UBI DBG bld: %s: " fmt "\n", __FUNCTION__, \
+ ##__VA_ARGS__)
+#else
+#define dbg_bld(fmt, ...) ({})
+#endif
+
+#ifdef CONFIG_MTD_UBI_DEBUG_EMULATE_BITFLIPS
+/**
+ * ubi_dbg_is_bitflip - if it is time to emulate a bit-flip.
+ *
+ * Returns non-zero if a bit-flip should be emulated, otherwise returns zero.
+ */
+static inline int ubi_dbg_is_bitflip(void)
+{
+ return !(random32() % 200);
+}
+#else
+#define ubi_dbg_is_bitflip() 0
+#endif
+
+#ifdef CONFIG_MTD_UBI_DEBUG_EMULATE_WRITE_FAILURES
+/**
+ * ubi_dbg_is_write_failure - if it is time to emulate a write failure.
+ *
+ * Returns non-zero if a write failure should be emulated, otherwise returns
+ * zero.
+ */
+static inline int ubi_dbg_is_write_failure(void)
+{
+ return !(random32() % 500);
+}
+#else
+#define ubi_dbg_is_write_failure() 0
+#endif
+
+#ifdef CONFIG_MTD_UBI_DEBUG_EMULATE_ERASE_FAILURES
+/**
+ * ubi_dbg_is_erase_failure - if its time to emulate an erase failure.
+ *
+ * Returns non-zero if an erase failure should be emulated, otherwise returns
+ * zero.
+ */
+static inline int ubi_dbg_is_erase_failure(void)
+{
+ return !(random32() % 400);
+}
+#else
+#define ubi_dbg_is_erase_failure() 0
+#endif
+
+#endif /* !__UBI_DEBUG_H__ */
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 18/20 take 4] UBI: JFFS2 UBI support
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (16 preceding siblings ...)
2007-03-23 16:44 ` [PATCH 17/20 take 4] UBI: debugging stuff Artem Bityutskiy
@ 2007-03-23 16:44 ` Artem Bityutskiy
2007-03-23 16:44 ` [PATCH 19/20 take 4] UBI: update MAINTAINERS Artem Bityutskiy
2007-03-23 16:44 ` [PATCH 20/20 take 4] UBI: linux build integration Artem Bityutskiy
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:44 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
diff -auNrp tmp-from/fs/jffs2/fs.c tmp-to/fs/jffs2/fs.c
--- tmp-from/fs/jffs2/fs.c 2007-03-23 18:20:01.000000000 +0200
+++ tmp-to/fs/jffs2/fs.c 2007-03-23 18:20:02.000000000 +0200
@@ -672,6 +672,13 @@ static int jffs2_flash_setup(struct jffs
return ret;
}
+ /* and an UBI volume */
+ if (jffs2_ubivol(c)) {
+ ret = jffs2_ubivol_setup(c);
+ if (ret)
+ return ret;
+ }
+
return ret;
}
@@ -690,4 +697,9 @@ void jffs2_flash_cleanup(struct jffs2_sb
if (jffs2_nor_wbuf_flash(c)) {
jffs2_nor_wbuf_flash_cleanup(c);
}
+
+ /* and an UBI volume */
+ if (jffs2_ubivol(c)) {
+ jffs2_ubivol_cleanup(c);
+ }
}
diff -auNrp tmp-from/fs/jffs2/os-linux.h tmp-to/fs/jffs2/os-linux.h
--- tmp-from/fs/jffs2/os-linux.h 2007-03-23 18:20:01.000000000 +0200
+++ tmp-to/fs/jffs2/os-linux.h 2007-03-23 18:20:02.000000000 +0200
@@ -98,6 +98,9 @@ static inline void jffs2_init_inode_info
#define jffs2_nor_wbuf_flash(c) (0)
#define jffs2_nor_wbuf_flash_setup(c) (0)
#define jffs2_nor_wbuf_flash_cleanup(c) do {} while (0)
+#define jffs2_ubivol(c) (0)
+#define jffs2_ubivol_setup(c) (0)
+#define jffs2_ubivol_cleanup(c) do {} while (0)
#else /* NAND and/or ECC'd NOR support present */
@@ -133,6 +136,9 @@ void jffs2_nand_flash_cleanup(struct jff
#define jffs2_dataflash(c) (c->mtd->type == MTD_DATAFLASH)
int jffs2_dataflash_setup(struct jffs2_sb_info *c);
void jffs2_dataflash_cleanup(struct jffs2_sb_info *c);
+#define jffs2_ubivol(c) (c->mtd->type == MTD_UBIVOLUME)
+int jffs2_ubivol_setup(struct jffs2_sb_info *c);
+void jffs2_ubivol_cleanup(struct jffs2_sb_info *c);
#define jffs2_nor_wbuf_flash(c) (c->mtd->type == MTD_NORFLASH && ! (c->mtd->flags & MTD_BIT_WRITEABLE))
int jffs2_nor_wbuf_flash_setup(struct jffs2_sb_info *c);
diff -auNrp tmp-from/fs/jffs2/wbuf.c tmp-to/fs/jffs2/wbuf.c
--- tmp-from/fs/jffs2/wbuf.c 2007-03-23 18:20:01.000000000 +0200
+++ tmp-to/fs/jffs2/wbuf.c 2007-03-23 18:20:02.000000000 +0200
@@ -1274,3 +1274,27 @@ int jffs2_nor_wbuf_flash_setup(struct jf
void jffs2_nor_wbuf_flash_cleanup(struct jffs2_sb_info *c) {
kfree(c->wbuf);
}
+
+int jffs2_ubivol_setup(struct jffs2_sb_info *c) {
+ c->cleanmarker_size = 0;
+
+ if (c->mtd->writesize == 1)
+ /* We do not need write-buffer */
+ return 0;
+
+ init_rwsem(&c->wbuf_sem);
+
+ c->wbuf_pagesize = c->mtd->writesize;
+ c->wbuf_ofs = 0xFFFFFFFF;
+ c->wbuf = kmalloc(c->wbuf_pagesize, GFP_KERNEL);
+ if (!c->wbuf)
+ return -ENOMEM;
+
+ printk(KERN_INFO "JFFS2 write-buffering enabled buffer (%d) erasesize (%d)\n", c->wbuf_pagesize, c->sector_size);
+
+ return 0;
+}
+
+void jffs2_ubivol_cleanup(struct jffs2_sb_info *c) {
+ kfree(c->wbuf);
+}
diff -auNrp tmp-from/include/mtd/mtd-abi.h tmp-to/include/mtd/mtd-abi.h
--- tmp-from/include/mtd/mtd-abi.h 2007-03-23 18:20:01.000000000 +0200
+++ tmp-to/include/mtd/mtd-abi.h 2007-03-23 18:20:02.000000000 +0200
@@ -24,6 +24,7 @@ struct mtd_oob_buf {
#define MTD_NORFLASH 3
#define MTD_NANDFLASH 4
#define MTD_DATAFLASH 6
+#define MTD_UBIVOLUME 7
#define MTD_WRITEABLE 0x400 /* Device is writeable */
#define MTD_BIT_WRITEABLE 0x800 /* Single bits can be flipped */
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 19/20 take 4] UBI: update MAINTAINERS
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (17 preceding siblings ...)
2007-03-23 16:44 ` [PATCH 18/20 take 4] UBI: JFFS2 UBI support Artem Bityutskiy
@ 2007-03-23 16:44 ` Artem Bityutskiy
2007-03-23 16:44 ` [PATCH 20/20 take 4] UBI: linux build integration Artem Bityutskiy
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:44 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
diff -auNrp tmp-from/MAINTAINERS tmp-to/MAINTAINERS
--- tmp-from/MAINTAINERS 2007-03-23 18:20:01.000000000 +0200
+++ tmp-to/MAINTAINERS 2007-03-23 18:20:02.000000000 +0200
@@ -2176,6 +2176,14 @@ L: linux-mtd@lists.infradead.org
T: git git://git.infradead.org/mtd-2.6.git
S: Maintained
+UNSORTED BLOCK IMAGES (UBI)
+P: Artem Bityutskiy
+M: dedekind@infradead.org
+W: http://www.linux-mtd.infradead.org/
+L: linux-mtd@lists.infradead.org
+T: git git://git.infradead.org/ubi-2.6.git
+S: Maintained
+
MICROTEK X6 SCANNER
P: Oliver Neukum
M: oliver@neukum.name
^ permalink raw reply [flat|nested] 22+ messages in thread* [PATCH 20/20 take 4] UBI: linux build integration
2007-03-23 16:42 [PATCH 00/20 take 4] UBI: Unsorted Block Images Artem Bityutskiy
` (18 preceding siblings ...)
2007-03-23 16:44 ` [PATCH 19/20 take 4] UBI: update MAINTAINERS Artem Bityutskiy
@ 2007-03-23 16:44 ` Artem Bityutskiy
19 siblings, 0 replies; 22+ messages in thread
From: Artem Bityutskiy @ 2007-03-23 16:44 UTC (permalink / raw)
To: Linux Kernel Mailing List
Cc: Frank Haverkamp, David Woodhouse, Josh Boyer, Artem Bityutskiy
diff -auNrp tmp-from/drivers/mtd/Kconfig tmp-to/drivers/mtd/Kconfig
--- tmp-from/drivers/mtd/Kconfig 2007-03-23 18:20:01.000000000 +0200
+++ tmp-to/drivers/mtd/Kconfig 2007-03-23 18:20:01.000000000 +0200
@@ -292,5 +292,7 @@ source "drivers/mtd/nand/Kconfig"
source "drivers/mtd/onenand/Kconfig"
+source "drivers/mtd/ubi/Kconfig"
+
endmenu
diff -auNrp tmp-from/drivers/mtd/Makefile tmp-to/drivers/mtd/Makefile
--- tmp-from/drivers/mtd/Makefile 2007-03-23 18:20:01.000000000 +0200
+++ tmp-to/drivers/mtd/Makefile 2007-03-23 18:20:01.000000000 +0200
@@ -28,3 +28,5 @@ nftl-objs := nftlcore.o nftlmount.o
inftl-objs := inftlcore.o inftlmount.o
obj-y += chips/ maps/ devices/ nand/ onenand/
+
+obj-$(CONFIG_MTD_UBI) += ubi/
diff -auNrp tmp-from/drivers/mtd/ubi/Kconfig tmp-to/drivers/mtd/ubi/Kconfig
--- tmp-from/drivers/mtd/ubi/Kconfig 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/Kconfig 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,58 @@
+# drivers/mtd/ubi/Kconfig
+
+menu "UBI - Unsorted block images"
+ depends on MTD
+
+config MTD_UBI
+ tristate "Enable UBI"
+ depends on MTD
+ select CRC32
+ help
+ UBI is a software layer above MTD layer which admits of LVM-like
+ logical volumes on top of MTD devices, hides some complexities of
+ flash chips like wear and bad blocks and provides some other useful
+ capabilities. Please, consult the MTD web site for more details
+ (www.linux-mtd.infradead.org).
+
+config MTD_UBI_WL_THRESHOLD
+ int "UBI wear-leveling threshold"
+ default 4096
+ range 2 65536
+ depends on MTD_UBI
+ help
+ This parameter defines the maximum difference between the highest
+ erase counter value and the lowest erase counter value of eraseblocks
+ of UBI devices. When this threshold is exceeded, UBI starts performing
+ wear leveling by means of moving data from eraseblock with low erase
+ counter to eraseblocks with high erase counter. Leave the default
+ value if unsure.
+
+config MTD_UBI_BEB_RESERVE
+ int "Percentage of reserved eraseblocks for bad eraseblocks handling"
+ default 1
+ range 0 25
+ depends on MTD_UBI
+ help
+ If the MTD device admits of bad eraseblocks (e.g. NAND flash), UBI
+ reserves some amount of physical eraseblocks to handle new bad
+ eraseblocks. For example, if a flash physical eraseblock becomes bad,
+ UBI uses these reserved physical eraseblocks to relocate the bad one.
+ This option specifies how many physical eraseblocks will be reserved
+ for bad eraseblock handling (percents of total number of good flash
+ eraseblocks). If the underlying flash does not admit of bad
+ eraseblocks (e.g. NOR flash), this value is ignored and nothing is
+ reserved. Leave the default value if unsure.
+
+config MTD_UBI_GLUEBI
+ bool "Emulate MTD devices"
+ default n
+ depends on MTD_UBI
+ help
+ This option enables MTD devices emulation on top of UBI volumes: for
+ each UBI volumes an MTD device is created, and all I/O to this MTD
+ device is redirected to the UBI volume. This is handy to make
+ MTD-oriented software (like JFFS2) work on top of UBI. Do not enable
+ this if no legacy software will be used.
+
+source "drivers/mtd/ubi/Kconfig.debug"
+endmenu
diff -auNrp tmp-from/drivers/mtd/ubi/Kconfig.debug tmp-to/drivers/mtd/ubi/Kconfig.debug
--- tmp-from/drivers/mtd/ubi/Kconfig.debug 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/Kconfig.debug 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,104 @@
+comment "UBI debugging options"
+ depends on MTD_UBI
+
+config MTD_UBI_DEBUG
+ bool "UBI debugging"
+ depends on SYSFS
+ depends on MTD_UBI
+ select DEBUG_FS
+ select KALLSYMS_ALL
+ help
+ This option enables UBI debugging.
+
+config MTD_UBI_DEBUG_MSG
+ bool "UBI debugging messages"
+ depends on MTD_UBI_DEBUG
+ default n
+ help
+ This option enables UBI debugging messages.
+
+config MTD_UBI_DEBUG_PARANOID
+ bool "Extra self-checks"
+ default n
+ depends on MTD_UBI_DEBUG
+ help
+ This option enables extra checks in UBI code. Note this slows UBI down
+ significantly.
+
+config MTD_UBI_DEBUG_DISABLE_BGT
+ bool "Do not enable the UBI background thread"
+ depends on MTD_UBI_DEBUG
+ default n
+ help
+ This option switches the background thread off by default. The thread
+ may be also be enabled/disabled via UBI sysfs.
+
+config MTD_UBI_DEBUG_USERSPACE_IO
+ bool "Direct user-space write/erase support"
+ default n
+ depends on MTD_UBI_DEBUG
+ help
+ By default, users cannot directly write and erase individual
+ eraseblocks of dynamic volumes, and have to use update operation
+ instead. This option enables this capability - it is very useful for
+ debugging and testing.
+
+config MTD_UBI_DEBUG_EMULATE_BITFLIPS
+ bool "Emulate flash bit-flips"
+ depends on MTD_UBI_DEBUG
+ default n
+ help
+ This option emulates bit-flips with probability 1/50, which in turn
+ causes scrubbing. Useful for debugging and stressing UBI.
+
+config MTD_UBI_DEBUG_EMULATE_WRITE_FAILURES
+ bool "Emulate flash write failures"
+ depends on MTD_UBI_DEBUG
+ default n
+ help
+ This option emulates write failures with probability 1/100. Useful for
+ debugging and testing how UBI handlines errors.
+
+config MTD_UBI_DEBUG_EMULATE_ERASE_FAILURES
+ bool "Emulate flash erase failures"
+ depends on MTD_UBI_DEBUG
+ default n
+ help
+ This option emulates erase failures with probability 1/100. Useful for
+ debugging and testing how UBI handlines errors.
+
+menu "Additional UBI debugging messages"
+ depends on MTD_UBI_DEBUG
+
+config MTD_UBI_DEBUG_MSG_BLD
+ bool "Additional UBI initialization and build messages"
+ default n
+ depends on MTD_UBI_DEBUG
+ help
+ This option enables detailed UBI initialization and device build
+ debugging messages.
+
+config MTD_UBI_DEBUG_MSG_EBA
+ bool "Eraseblock association unit messages"
+ default n
+ depends on MTD_UBI_DEBUG
+ help
+ This option enables debugging messages from the UBI eraseblock
+ association unit.
+
+config MTD_UBI_DEBUG_MSG_WL
+ bool "Wear-leveling unit messages"
+ default n
+ depends on MTD_UBI_DEBUG
+ help
+ This option enables debugging messages from the UBI wear-leveling
+ unit.
+
+config MTD_UBI_DEBUG_MSG_IO
+ bool "Input/output unit messages"
+ default n
+ depends on MTD_UBI_DEBUG
+ help
+ This option enables debugging messages from the UBI input/output unit.
+
+endmenu # UBI debugging messages
diff -auNrp tmp-from/drivers/mtd/ubi/Makefile tmp-to/drivers/mtd/ubi/Makefile
--- tmp-from/drivers/mtd/ubi/Makefile 1970-01-01 02:00:00.000000000 +0200
+++ tmp-to/drivers/mtd/ubi/Makefile 2007-03-23 18:20:01.000000000 +0200
@@ -0,0 +1,7 @@
+obj-$(CONFIG_MTD_UBI) += ubi.o
+
+ubi-y += vtbl.o vmt.o upd.o build.o cdev.o kapi.o eba.o io.o wl.o scan.o
+ubi-y += misc.o
+
+ubi-$(CONFIG_MTD_UBI_DEBUG) += debug.o
+ubi-$(CONFIG_MTD_UBI_GLUEBI) += gluebi.o
diff -auNrp tmp-from/include/mtd/Kbuild tmp-to/include/mtd/Kbuild
--- tmp-from/include/mtd/Kbuild 2007-03-23 18:20:01.000000000 +0200
+++ tmp-to/include/mtd/Kbuild 2007-03-23 18:20:01.000000000 +0200
@@ -3,3 +3,5 @@ header-y += jffs2-user.h
header-y += mtd-abi.h
header-y += mtd-user.h
header-y += nftl-user.h
+header-y += ubi-header.h
+header-y += ubi-user.h
^ permalink raw reply [flat|nested] 22+ messages in thread