Re: [PATCH] block: Fix LSF default inconsistency

[Jens Axboe <jens.axboe@oracle.com>]

On Fri, Dec 12 2008, Jean Delvare wrote:
> Hi Jens,
> 
> On Thu, 11 Dec 2008 13:50:01 +0100, Jens Axboe wrote:
> > Oh right, that's pretty dumb. Lets just do the former, then a later
> > patch can replace it completely if wanted.
> > 
> > diff --git a/block/Kconfig b/block/Kconfig
> > index 1ab7c15..a785e65 100644
> > --- a/block/Kconfig
> > +++ b/block/Kconfig
> > @@ -23,22 +23,22 @@ menuconfig BLOCK
> >  
> >  if BLOCK
> >  
> > +config LSF
> > +	bool
> > +
> >  config LBD
> > -	bool "Support for Large Block Devices"
> > +	bool "Support for Large Block Devices and files"
> 
> It might be the right time to drop the extra capital letters, for
> consistency.

Agree, it's pretty ugly. Modified patch below, it drops CONFIG_LSF
completely as it's basically only used in a single spot.

> >  	depends on !64BIT
> > +	select LSF
> >  	help
> > -	  Enable block devices of size 2TB and larger.
> > +	  Enable block devices or files of size 2TB and larger.
> >  
> >  	  This option is required to support the full capacity of large
> >  	  (2TB+) block devices, including RAID, disk, Network Block Device,
> >  	  Logical Volume Manager (LVM) and loopback.
> > -
> > -	  For example, RAID devices are frequently bigger than the capacity
> > -	  of the largest individual hard drive.
> > -
> > -	  This option is not required if you have individual disk drives
> > -	  which total 2TB+ and you are not aggregating the capacity into
> > -	  a large block device (e.g. using RAID or LVM).
> > +	
> > +	  This option also enables support for single files larger than
> > +	  2TB.
> >  
> >  	  If unsure, say N.
> >  
> > @@ -57,15 +57,6 @@ config BLK_DEV_IO_TRACE
> >  
> >  	  If unsure, say N.
> >  
> > -config LSF
> > -	bool "Support for Large Single Files"
> > -	depends on !64BIT
> > -	help
> > -	  Say Y here if you want to be able to handle very large files (2TB
> > -	  and larger), otherwise say N.
> > -
> > -	  If unsure, say Y.
> > -
> >  config BLK_DEV_BSG
> >  	bool "Block layer SG support v4 (EXPERIMENTAL)"
> >  	depends on EXPERIMENTAL
> > 
> 
> Acked-by: Jean Delvare <khali@linux-fr.org>
> 
> As a side note, someone will have to tell me why changing the value of
> option LSF triggers a full kernel rebuild.

It changes types.h, I guess pretty much everything has that included :-)

diff --git a/block/Kconfig b/block/Kconfig
index 1ab7c15..195968e 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -24,21 +24,17 @@ menuconfig BLOCK
 if BLOCK
 
 config LBD
-	bool "Support for Large Block Devices"
+	bool "Support for large block devices and files"
 	depends on !64BIT
 	help
-	  Enable block devices of size 2TB and larger.
+	  Enable block devices or files of size 2TB and larger.
 
 	  This option is required to support the full capacity of large
 	  (2TB+) block devices, including RAID, disk, Network Block Device,
 	  Logical Volume Manager (LVM) and loopback.
-
-	  For example, RAID devices are frequently bigger than the capacity
-	  of the largest individual hard drive.
-
-	  This option is not required if you have individual disk drives
-	  which total 2TB+ and you are not aggregating the capacity into
-	  a large block device (e.g. using RAID or LVM).
+	
+	  This option also enables support for single files larger than
+	  2TB.
 
 	  If unsure, say N.
 
@@ -57,15 +53,6 @@ config BLK_DEV_IO_TRACE
 
 	  If unsure, say N.
 
-config LSF
-	bool "Support for Large Single Files"
-	depends on !64BIT
-	help
-	  Say Y here if you want to be able to handle very large files (2TB
-	  and larger), otherwise say N.
-
-	  If unsure, say Y.
-
 config BLK_DEV_BSG
 	bool "Block layer SG support v4 (EXPERIMENTAL)"
 	depends on EXPERIMENTAL
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index e4a241c..04158ad 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1721,7 +1721,7 @@ static loff_t ext4_max_size(int blkbits, int has_huge_files)
 	/* small i_blocks in vfs inode? */
 	if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
 		/*
-		 * CONFIG_LSF is not enabled implies the inode
+		 * CONFIG_LBD is not enabled implies the inode
 		 * i_block represent total blocks in 512 bytes
 		 * 32 == size of vfs inode i_blocks * 8
 		 */
@@ -1764,7 +1764,7 @@ static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
 
 	if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
 		/*
-		 * !has_huge_files or CONFIG_LSF is not enabled
+		 * !has_huge_files or CONFIG_LBD is not enabled
 		 * implies the inode i_block represent total blocks in
 		 * 512 bytes 32 == size of vfs inode i_blocks * 8
 		 */
@@ -2021,13 +2021,13 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 	if (has_huge_files) {
 		/*
 		 * Large file size enabled file system can only be
-		 * mount if kernel is build with CONFIG_LSF
+		 * mount if kernel is build with CONFIG_LBD
 		 */
 		if (sizeof(root->i_blocks) < sizeof(u64) &&
 				!(sb->s_flags & MS_RDONLY)) {
 			printk(KERN_ERR "EXT4-fs: %s: Filesystem with huge "
 					"files cannot be mounted read-write "
-					"without CONFIG_LSF.\n", sb->s_id);
+					"without CONFIG_LBD.\n", sb->s_id);
 			goto failed_mount;
 		}
 	}
diff --git a/include/linux/types.h b/include/linux/types.h
index 1d98330..121f349 100644
--- a/include/linux/types.h
+++ b/include/linux/types.h
@@ -135,19 +135,14 @@ typedef		__s64		int64_t;
  *
  * Linux always considers sectors to be 512 bytes long independently
  * of the devices real block size.
+ *
+ * blkcnt_t is the type of the inode's block count.
  */
 #ifdef CONFIG_LBD
 typedef u64 sector_t;
-#else
-typedef unsigned long sector_t;
-#endif
-
-/*
- * The type of the inode's block count.
- */
-#ifdef CONFIG_LSF
 typedef u64 blkcnt_t;
 #else
+typedef unsigned long sector_t;
 typedef unsigned long blkcnt_t;
 #endif
 

-- 
Jens Axboe