[00/11] xfs_scrub: fix IO error detection during media verify

Message

Darrick J. Wong Sept. 6, 2019, 3:37 a.m. UTC

Hi all,

The existing scrub media scan code (phase 6) has a lot of problems
dealing with errors.  It treats runtime errors (e.g. ENOMEM) as disk
errors, it fails to handle short reads properly, it reports entire
extents as failed when the read returns EIO instead of single-stepping
filesystem blocks to find the bad ones, and there's no good way to test
that it works.

This series fixes each of those problems and adds a couple of debugging
knobs so that we can simulate disk errors and short reads to make sure
that the media scan code actually detects media errors correctly.

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-detection