[00/11] xfs_scrub: fix IO error reporting

Message

Darrick J. Wong Sept. 25, 2019, 9:36 p.m. UTC

Hi all,

The scrub media error reporting could use some improvements -- first,
scrub can calculate the exact offset of media errors in file mappings,
so we should report more precise offsets.  Second, we only need to scan
the rmap once after assembling the io error bitmap to look for destroyed
metadata (instead of once per error!).  Third, we can filter out
unwritten and attr/cow fork extents from what we report since sector
remapping takes care of unwritten/cow extents and attr media errors
should be detected by phase 3.  Finally, we introduce a new category of
errors that are unfixable by scrub, and assign to this class all the
media errors since there's nothing XFS can do.

If you're going to start using this mess, you probably ought to just
pull from my git trees, which are linked below.

This is an extraordinary way to destroy everything.  Enjoy!
Comments and questions are, as always, welcome.

--D

xfsprogs git tree:
https://git.kernel.org/cgit/linux/kernel/git/djwong/xfsprogs-dev.git/log/?h=scrub-media-error-reporting

fstests git tree:
https://git.kernel.org/cgit/linux/kernel/git/djwong/xfstests-dev.git/log/?h=scrub-media-error-reporting