[PATCH v4 0/6] ext4: fix a inode checksum error

[Zhang Yi <yi.zhang@huawei.com>]

We find a checksum error and a inode corruption problem while doing
stress test, this 6 patches address to fix them. The first patch is
relate to the error simulation, and the 2-5 patches are prepare to
do the fix. The last patch fix these two issue.

 - Checksum error

    EXT4-fs error (device sda): ext4_lookup:1784: inode #131074: comm cat: iget: checksum invalid

 - Inode corruption

    e2fsck 1.46.0 (29-Jan-2020)
    Pass 1: Checking inodes, blocks, and sizes
    Pass 2: Checking directory structure
    Entry 'foo' in / (2) has deleted/unused inode 17.  Clear<y>? yes
    Pass 3: Checking directory connectivity
    Pass 4: Checking reference counts
    Pass 5: Checking group summary information
    Inode bitmap differences:  -17
    Fix<y>? yes
    Free inodes count wrong for group #0 (32750, counted=32751).
    Fix<y>? yes
    Free inodes count wrong (32750, counted=32751).
    Fix<y>? yes

Changes since v3:
 - Postpone initialization to ext4_do_update_inode() may cause zeroout
   newly set xattr entry. So switch to do initialization in
   __ext4_get_inode_loc().

Changes since v2:
 - Instead of using WARN_ON_ONCE to prevent ext4_do_update_inode()
   return before filling the inode buffer, keep the error and postpone
   the report after the updating in the third patch.
 - Fix some language mistacks in the last patch.

Changes since v1:
 - Add a patch to prevent ext4_do_update_inode() return before filling
   the inode buffer.
 - Do not use BH_New flag to indicate the empty buffer, postpone the
   zero and uptodate logic into ext4_do_update_inode() before filling
   the inode buffer.

Thanks,
Yi.

Zhang Yi (6):
  ext4: move inode eio simulation behind io completeion
  ext4: remove an unnecessary if statement in __ext4_get_inode_loc()
  ext4: make the updating inode data procedure atomic
  ext4: factor out ext4_fill_raw_inode()
  ext4: move ext4_fill_raw_inode() related functions
  ext4: prevent getting empty inode buffer

 fs/ext4/inode.c | 490 +++++++++++++++++++++++++-----------------------
 1 file changed, 257 insertions(+), 233 deletions(-)

-- 
2.31.1