diff options
| author | Tao Ma <boyu.mt@taobao.com> | 2012-05-28 18:20:59 -0400 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2012-05-28 18:20:59 -0400 |
| commit | 6f2e9f0e7d795214b9cf5a47724a273b705fd113 (patch) | |
| tree | c33979cd8d907b0eab9e3d9eada09a09e222e54a /fs/ext4/ialloc.c | |
| parent | 8563000d3bf3ccfccce335c092a7c43078be8ffd (diff) | |
| download | linux-6f2e9f0e7d795214b9cf5a47724a273b705fd113.tar.gz linux-6f2e9f0e7d795214b9cf5a47724a273b705fd113.tar.bz2 linux-6f2e9f0e7d795214b9cf5a47724a273b705fd113.zip | |
ext4: protect group inode free counting with group lock
Now when we set the group inode free count, we don't have a proper
group lock so that multiple threads may decrease the inode free
count at the same time. And e2fsck will complain something like:
Free inodes count wrong for group #1 (1, counted=0).
Fix? no
Free inodes count wrong for group #2 (3, counted=0).
Fix? no
Directories count wrong for group #2 (780, counted=779).
Fix? no
Free inodes count wrong for group #3 (2272, counted=2273).
Fix? no
So this patch try to protect it with the ext4_lock_group.
btw, it is found by xfstests test case 269 and the volume is
mkfsed with the parameter
"-O ^resize_inode,^uninit_bg,extent,meta_bg,flex_bg,ext_attr"
and I have run it 100 times and the error in e2fsck doesn't
show up again.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Diffstat (limited to 'fs/ext4/ialloc.c')
| -rw-r--r-- | fs/ext4/ialloc.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index ea32d7e1d6e3..03583ab52e0e 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -797,7 +797,10 @@ got: ext4_itable_unused_set(sb, gdp, (EXT4_INODES_PER_GROUP(sb) - ino)); up_read(&grp->alloc_sem); + } else { + ext4_lock_group(sb, group); } + ext4_free_inodes_set(sb, gdp, ext4_free_inodes_count(sb, gdp) - 1); if (S_ISDIR(mode)) { ext4_used_dirs_set(sb, gdp, ext4_used_dirs_count(sb, gdp) + 1); @@ -811,8 +814,8 @@ got: ext4_inode_bitmap_csum_set(sb, group, gdp, inode_bitmap_bh, EXT4_INODES_PER_GROUP(sb) / 8); ext4_group_desc_csum_set(sb, group, gdp); - ext4_unlock_group(sb, group); } + ext4_unlock_group(sb, group); BUFFER_TRACE(inode_bitmap_bh, "call ext4_handle_dirty_metadata"); err = ext4_handle_dirty_metadata(handle, NULL, inode_bitmap_bh); |