From: Baokun Li <libaokun1@xxxxxxxxxx>
Changes since v1:
* Patch 5: Make data_err=abort work for all Buffer IO, not just add
support in dioread_nolock mode.
* Add patch 3,4,6.
* Collect RVB from Jan Kara and Zhang Yi.(Thanks for your review!)
v1: https://lore.kernel.org/r/20241220060757.1781418-1-libaokun@xxxxxxxxxxxxxxx
Recently some of our customers remounted ext4 from
"dioread_nolock,data_err=abort" to "dioread_lock,data_err=abort" and the
ext4 filesystem became read-only.
Then I found that "data_err=abort" is not working in dioread_nolock mode,
when data writeback fails, the error is always recorded in inode mapping,
but no one will check it, not even when converting unwritten to written,
which could expose stale data. When remounted with dioread_lock, the error
recorded in the inode mapping was checked and the journal aborted, and the
file system became read-only later.
Patch 1: Clean up duplicate code and ensure that an warning is printed
when data may be lost;
Patch 2: Fix an issue that could expose stale data when data writeback
fails;
Patch 3: Reject data_err=abort in nojournal mode to ensure
sbi->s_journal != NULL when DATA_ERR_ABORT set.
Patch 4: Add the ext4_check_nojournal_options() helper to
reduce code duplication.
Patch 5: Make data_err=abort work for all Buffer IO, not just order mode.
Patch 6: Update the description of data_err=abort|ignore in the DOC.
Patch 7: Remove useless i_unwritten and related code.
Patch 8: Pack holes in ext4_inode_info to save memory.
Comments and questions are, as always, welcome.
Thanks,
Baokun
Baokun Li (8):
ext4: replace opencoded ext4_end_io_end() in ext4_put_io_end()
ext4: do not convert the unwritten extents if data writeback fails
ext4: reject the 'data_err=abort' option in nojournal mode
ext4: extract ext4_check_nojournal_options() from __ext4_fill_super()
ext4: abort journal on data writeback failure if in data_err=abort mode
ext4: update the descriptions of data_err=abort and data_err=ignore
ext4: remove unused member 'i_unwritten' from 'ext4_inode_info'
ext4: pack holes in ext4_inode_info
Documentation/admin-guide/ext4.rst | 7 ++-
fs/ext4/ext4.h | 34 ++++----------
fs/ext4/inode.c | 2 +-
fs/ext4/page-io.c | 75 ++++++++++++++++++++----------
fs/ext4/super.c | 61 +++++++++++++-----------
5 files changed, 98 insertions(+), 81 deletions(-)
--
2.39.2
