Patchset can be fetched from github:
https://github.com/adam900710/linux/tree/write_time_tree_checker
Which is based on v5.1-rc1 tag.
This patchset has the following 3 features:
- Tree block validation output enhancement
* Output validation failure timing (write time or read time)
* Always output tree block level/key mismatch error message
This part is already submitted and reviewed.
- Write time tree block validation check
To catch memory corruption either from hardware or kernel.
Example output would be:
BTRFS critical (device dm-3): corrupt leaf: root=2 block=1350630375424
slot=68, bad key order, prev (10510212874240 169 0) current (1714119868416 169
0)
BTRFS error (device dm-3): block=1350630375424 write time tree block
corruption detected
BTRFS: error (device dm-3) in btrfs_commit_transaction:2220: errno=-5 IO
failure (Error while writing out transaction)
BTRFS info (device dm-3): forced readonly
BTRFS warning (device dm-3): Skipping commit of aborted transaction.
BTRFS: error (device dm-3) in cleanup_transaction:1839: errno=-5 IO failure
BTRFS info (device dm-3): delayed_refs has NO entry
- Better error handling before calling flush_write_bio()
One hidden reason of calling flush_write_bio() under all cases is,
flush_write_bio() will trigger endio function and endio function of
epd->bio will free the bio under all cases.
So we're in fact abusing flush_write_bio() as cleanup.
Since now flush_write_bio() has its own return value, we shouldn't call
flush_write_bio() no-brain, here we introduce proper cleanup helper,
end_write_bio(). Now we call flush_write_bio() like:
New | Old
--------------------------------------------------------------
ret = do_some_evil(&epd); | ret = do_some_evil(&epd);
if (ret < 0) { | flush_write_bio(&epd);
end_write_bio(&epd, ret); | ^^^ submitting half-backed epd->bio?
return ret; | return ret;
} |
ret = flush_write_bio(&epd); |
return ret; |
Above code should be more streamline for the error handling part.
Changelog:
v2:
- Unlock locked pages in lock_extent_buffer_for_io() for error handling.
- Added Reviewed-by tags.
v3:
- Remove duplicated error message.
- Use IS_ENABLED() macro to replace #ifdef.
- Added Reviewed-by tags.
v4:
- Re-organized patch split
Now each BUG_ON() cleanup has its own patch
- Dig much further into the call sites to eliminate unexpected >0 return
May be a little paranoid and abuse some ASSERT(), but it should be
much safer against further code change.
- Fix the false alert caused by balance and memory pressure
The fix it skip owner checker for non-essential tree at write time.
Since owner root can't always be reliable, either due to commit root
created in current transaction or balance + memory pressure.
v5:
- Do proper error-out handling other than relying on flush_write_bio()
to clean up.
This has a side effect that no Reviewed-by tags for modified patches.
- New comment for why we don't need to do anything about ebp->bio when
submit_one_bio() fails.
- Add some Reviewed-by tag.
v5.1:
- Add "block=%llu " output for write/read time error line.
- Also output read time error message for fsid/start/level check.
v5.2:
- Fix a missing page_unlock() in error hanlding
v5.3:
- Rebase to v5.1-rc1 tag
Qu Wenruo (11):
btrfs: Always output error message when key/level verification fails
btrfs: disk-io: Show the timing of corrupted tree block explicitly
btrfs: extent_io: Move the BUG_ON() in flush_write_bio() one level up
btrfs: extent_io: Handle error better in extent_write_full_page()
btrfs: extent_io: Handle error better in btree_write_cache_pages()
btrfs: extent_io: Kill the dead branch in extent_write_cache_pages()
btrfs: extent_io: Handle error better in extent_write_locked_range()
btrfs: extent_io: Kill the BUG_ON() in lock_extent_buffer_for_io()
btrfs: extent_io: Kill the BUG_ON() in extent_write_cache_pages()
btrfs: extent_io: Handle error better in extent_writepages()
btrfs: Do mandatory tree block check before submitting bio
fs/btrfs/disk-io.c | 24 ++++++---
fs/btrfs/extent_io.c | 109 +++++++++++++++++++++++++++++++++-------
fs/btrfs/tree-checker.c | 24 +++++++--
fs/btrfs/tree-checker.h | 8 +++
4 files changed, 137 insertions(+), 28 deletions(-)
--
2.21.0
