diff options
| author | Jeff Mahoney <jeffm@suse.com> | 2007-10-18 23:39:27 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-19 11:53:35 -0700 |
| commit | cb680c1be62e9898fc2ca2a89d9fdba7c84a5c81 (patch) | |
| tree | 967eba31bdb120305697f5d0292964abead07962 /fs/reiserfs/resize.c | |
| parent | 4d20851d3757ba5bece263a4c8c5a2bd4983cb5d (diff) | |
reiserfs: ignore on disk s_bmap_nr value
Implement support for file systems larger than 8 TiB.
The reiserfs superblock contains a 16 bit value for counting the number of
bitmap blocks. The rest of the disk format supports file systems up to 2^32
blocks, but the bitmap block limitation artificially limits this to 8 TiB with
a 4KiB block size.
Rather than trust the superblock's 16-bit bitmap block count, we calculate it
dynamically based on the number of blocks in the file system. When an
incorrect value is observed in the superblock, it is zeroed out, ensuring that
older kernels will not be able to mount the file system.
Userspace support has already been implemented and shipped in reiserfsprogs
3.6.20.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/reiserfs/resize.c')
| -rw-r--r-- | fs/reiserfs/resize.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/fs/reiserfs/resize.c b/fs/reiserfs/resize.c index 66f1cda83a81..f71c3948edef 100644 --- a/fs/reiserfs/resize.c +++ b/fs/reiserfs/resize.c @@ -61,7 +61,8 @@ int reiserfs_resize(struct super_block *s, unsigned long block_count_new) } /* count used bits in last bitmap block */ - block_r = SB_BLOCK_COUNT(s) - (SB_BMAP_NR(s) - 1) * s->s_blocksize * 8; + block_r = SB_BLOCK_COUNT(s) - + (reiserfs_bmap_count(s) - 1) * s->s_blocksize * 8; /* count bitmap blocks in new fs */ bmap_nr_new = block_count_new / (s->s_blocksize * 8); @@ -73,7 +74,7 @@ int reiserfs_resize(struct super_block *s, unsigned long block_count_new) /* save old values */ block_count = SB_BLOCK_COUNT(s); - bmap_nr = SB_BMAP_NR(s); + bmap_nr = reiserfs_bmap_count(s); /* resizing of reiserfs bitmaps (journal and real), if needed */ if (bmap_nr_new > bmap_nr) { @@ -200,7 +201,7 @@ int reiserfs_resize(struct super_block *s, unsigned long block_count_new) free_blocks + (block_count_new - block_count - (bmap_nr_new - bmap_nr))); PUT_SB_BLOCK_COUNT(s, block_count_new); - PUT_SB_BMAP_NR(s, bmap_nr_new); + PUT_SB_BMAP_NR(s, bmap_would_wrap(bmap_nr_new) ? : bmap_nr_new); s->s_dirt = 1; journal_mark_dirty(&th, s, SB_BUFFER_WITH_SB(s)); |