ntfs: set the attribute list size before reserving space for it

ntfs_attrlist_update_locked() resizes the attribute list and then, for
$MFT, tries to reserve the maximum list size.  When that allocation
fails with -ENOSPC it falls back to ntfs_attrlist_repack(), which reads
the list through ntfs_inode_attr_pread().  The read stops at i_size,
but i_size is only updated after the reserve, so when the list has just
grown the repack gets a short read and returns -EIO.  Only -ENOSPC from
the reserve is ignored, so the -EIO fails the $MFT extension and with
it the file creation that needed a new mft record.

On a 32 MiB volume with 512-byte clusters whose $MFT has a non-resident
attribute list, 591 of 1500 creations of empty files succeed and the
rest fail with EIO while 742 KiB is still free:

  ntfs: (device vda): ntfs_attrlist_update_locked(): Failed to reserve attribute list space
  ntfs: Failed add attr entry to attrlist
  ntfs: MP update failed
  ntfs: (device vda): ntfs_mft_record_alloc(): Failed to extend mft data allocation.

Update i_size as soon as the list has been resized.  File creation then
goes on until the volume is full and fails with ENOSPC.

Fixes: b1d732e62a5b ("ntfs: repack $MFT/$ATTRIBUTE LIST")
Signed-off-by: Matthias Goergens <matthias.goergens@gmail.com>
Reviewed-by: Baolin Liu <liubaolin@kylinos.cn>
Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>

0 files changed, 0 insertions, 0 deletions