The next 4 patches support large block size (up to PAGESIZE, max 64KB) for ext2/3/4, originally from Takashi Sato. http://marc.info/?l=linux-ext4&m=115768873518400&w=2 It's quite simple to support large block size in ext2/3/4, mostly just enlarge the block size limit. But it is NOT possible to have 64kB blocksize on ext2/3/4 without some changes to the directory handling code. The reason is that an empty 64kB directory block would have a rec_len == (__u16)2^16 == 0, and this would cause an error to be hit in the filesystem. The proposed solution is to put 2 empty records in such a directory, or to special-case an impossible value like rec_len = 0xffff to handle this. The Patch-set consists of the following 4 patches. [1/4] ext2/3/4: enlarge blocksize - Allow blocksize up to pagesize [2/4] ext2: fix rec_len overflow - prevent rec_len from overflow with 64KB blocksize [3/4] ext3: fix rec_len overflow - prevent rec_len from overflow with 64KB blocksize [4/4] ext4: fix rec_len overflow - prevent rec_len from overflow with 64KB blocksize Just rebase to 2.6.23-rc4 and against the ext4 patch queue. Compile tested only. Next steps: Need a e2fsprogs changes to able test this feature. As mkfs needs to be educated not assuming rec_len to be blocksize all the time. Will try it with Christoph Lameter's large block patch next. Signed-off-by: Takashi Sato <sho@xxxxxxxxxxxxxx> Signed-off-by: Mingming Cao <cmm@xxxxxxxxxx> --- --- fs/ext2/super.c | 2 +- fs/ext3/super.c | 5 ++++- fs/ext4/super.c | 5 +++++ include/linux/ext2_fs.h | 4 ++-- include/linux/ext3_fs.h | 4 ++-- include/linux/ext4_fs.h | 4 ++-- 6 files changed, 16 insertions(+), 8 deletions(-) Index: linux-2.6.23-rc3/fs/ext2/super.c =================================================================== --- linux-2.6.23-rc3.orig/fs/ext2/super.c 2007-08-12 21:25:24.000000000 -0700 +++ linux-2.6.23-rc3/fs/ext2/super.c 2007-08-29 15:22:29.000000000 -0700 @@ -775,7 +775,7 @@ static int ext2_fill_super(struct super_ brelse(bh); if (!sb_set_blocksize(sb, blocksize)) { - printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n"); + printk(KERN_ERR "EXT2-fs: bad blocksize %d.\n", blocksize); goto failed_sbi; } Index: linux-2.6.23-rc3/fs/ext3/super.c =================================================================== --- linux-2.6.23-rc3.orig/fs/ext3/super.c 2007-08-12 21:25:24.000000000 -0700 +++ linux-2.6.23-rc3/fs/ext3/super.c 2007-08-29 15:22:29.000000000 -0700 @@ -1549,7 +1549,10 @@ static int ext3_fill_super (struct super } brelse (bh); - sb_set_blocksize(sb, blocksize); + if (!sb_set_blocksize(sb, blocksize)) { + printk(KERN_ERR "EXT3-fs: bad blocksize %d.\n", blocksize); + goto out_fail; + } logic_sb_block = (sb_block * EXT3_MIN_BLOCK_SIZE) / blocksize; offset = (sb_block * EXT3_MIN_BLOCK_SIZE) % blocksize; bh = sb_bread(sb, logic_sb_block); Index: linux-2.6.23-rc3/fs/ext4/super.c =================================================================== --- linux-2.6.23-rc3.orig/fs/ext4/super.c 2007-08-28 11:09:40.000000000 -0700 +++ linux-2.6.23-rc3/fs/ext4/super.c 2007-08-29 15:24:08.000000000 -0700 @@ -1626,6 +1626,11 @@ static int ext4_fill_super (struct super goto out_fail; } + if (!sb_set_blocksize(sb, blocksize)) { + printk(KERN_ERR "EXT4-fs: bad blocksize %d.\n", blocksize); + goto out_fail; + } + /* * The ext4 superblock will not be buffer aligned for other than 1kB * block sizes. We need to calculate the offset from buffer start. Index: linux-2.6.23-rc3/include/linux/ext2_fs.h =================================================================== --- linux-2.6.23-rc3.orig/include/linux/ext2_fs.h 2007-08-12 21:25:24.000000000 -0700 +++ linux-2.6.23-rc3/include/linux/ext2_fs.h 2007-08-29 15:22:29.000000000 -0700 @@ -86,8 +86,8 @@ static inline struct ext2_sb_info *EXT2_ * Macro-instructions used to manage several block sizes */ #define EXT2_MIN_BLOCK_SIZE 1024 -#define EXT2_MAX_BLOCK_SIZE 4096 -#define EXT2_MIN_BLOCK_LOG_SIZE 10 +#define EXT2_MAX_BLOCK_SIZE 65536 +#define EXT2_MIN_BLOCK_LOG_SIZE 10 #ifdef __KERNEL__ # define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize) #else Index: linux-2.6.23-rc3/include/linux/ext3_fs.h =================================================================== --- linux-2.6.23-rc3.orig/include/linux/ext3_fs.h 2007-08-12 21:25:24.000000000 -0700 +++ linux-2.6.23-rc3/include/linux/ext3_fs.h 2007-08-29 15:22:29.000000000 -0700 @@ -76,8 +76,8 @@ * Macro-instructions used to manage several block sizes */ #define EXT3_MIN_BLOCK_SIZE 1024 -#define EXT3_MAX_BLOCK_SIZE 4096 -#define EXT3_MIN_BLOCK_LOG_SIZE 10 +#define EXT3_MAX_BLOCK_SIZE 65536 +#define EXT3_MIN_BLOCK_LOG_SIZE 10 #ifdef __KERNEL__ # define EXT3_BLOCK_SIZE(s) ((s)->s_blocksize) #else Index: linux-2.6.23-rc3/include/linux/ext4_fs.h =================================================================== --- linux-2.6.23-rc3.orig/include/linux/ext4_fs.h 2007-08-28 11:09:40.000000000 -0700 +++ linux-2.6.23-rc3/include/linux/ext4_fs.h 2007-08-29 15:22:29.000000000 -0700 @@ -104,8 +104,8 @@ struct ext4_allocation_request { * Macro-instructions used to manage several block sizes */ #define EXT4_MIN_BLOCK_SIZE 1024 -#define EXT4_MAX_BLOCK_SIZE 4096 -#define EXT4_MIN_BLOCK_LOG_SIZE 10 +#define EXT4_MAX_BLOCK_SIZE 65536 +#define EXT4_MIN_BLOCK_LOG_SIZE 10 #ifdef __KERNEL__ # define EXT4_BLOCK_SIZE(s) ((s)->s_blocksize) #else - To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
