Commit Graph

68 Commits

Author SHA1 Message Date
Jan Schmidt 5da6fcbc4e btrfs: integrating raid-repair and scrub-fixup-nodatasum
This ties nodatasum fixup in scrub together with raid repair patches. While
both series are working fine alone, scrub will report uncorrectable errors
if they occur in a nodatasum extent *and* the page is in the page cache.

Previously, we would have triggered readpage to find good data and do the
repair. However, readpage wouldn't read anything in the case where the page
is up to date in the cache. So, we simply take that good data we have and
call repair_io_failure directly (unless the page in the cache is dirty).

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2011-09-29 13:38:43 +02:00
Jan Schmidt a1d3c4786a btrfs: btrfs_multi_bio replaced with btrfs_bio
btrfs_bio is a bio abstraction able to split and not complete after the last
bio has returned (like the old btrfs_multi_bio). Additionally, btrfs_bio
tracks the mirror_num used to read data which can be used for error
correction purposes.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2011-09-29 13:38:42 +02:00
Jan Schmidt 0ef8e45158 btrfs scrub: add fixup code for errors on nodatasum files
This removes a FIXME comment and introduces the first part of nodatasum
fixup: It gets the corresponding inode for a logical address and triggers a
regular readpage for the corrupted sector.

Once we have on-the-fly error correction our error will be automatically
corrected. The correction code is expected to clear the newly introduced
EXTENT_DAMAGED flag, making scrub report that error as "corrected" instead
of "uncorrectable" eventually.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2011-09-29 12:54:28 +02:00
Jan Schmidt e12fa9cd39 btrfs scrub: use int for mirror_num, not u64
the rest of the code uses int mirror_num, and so should scrub

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2011-09-29 12:54:28 +02:00
Jan Schmidt 193ea74b27 btrfs scrub: bugfix: mirror_num off by one
Fix the mirror_num determination in scrub_stripe. The rest of the scrub code
did not use mirror_num for anything important and that error went unnoticed.
The nodatasum fixup patch of this set depends on a correct mirror_num.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2011-09-29 12:54:28 +02:00
Jan Schmidt 558540c177 btrfs scrub: print paths of corrupted files
While scrubbing, we may encounter various errors. Previously, a logical
address was printed to the log only. Now, all paths belonging to that
address are resolved and printed separately. That should work for hardlinks
as well as reflinks.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2011-09-29 12:54:28 +02:00
Jan Schmidt 13db62b7a1 btrfs scrub: added unverified_errors
In normal operation, scrub is reading data sequentially in large portions.
In case of an i/o error, we try to find the corrupted area(s) by issuing
page sized read requests. With this commit we increment the
unverified_errors counter if all of the small size requests succeed.

Userland patches carrying such conspicous events to the administrator should
already be around.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2011-09-29 12:54:27 +02:00
Arne Jansen 6eef312588 btrfs: remove unneeded includes from scrub.c
Signed-off-by: Arne Jansen <sensille@gmx.net>
2011-06-10 14:59:52 +02:00
Arne Jansen 632dd772fc btrfs: reinitialize scrub workers
Scrub starts the workers each time a scrub starts and stops them after it
finished. This patch adds an initialization for the workers before each
start, otherwise the workers behave strangely.

Signed-off-by: Arne Jansen <sensille@gmx.net>
2011-06-10 12:14:13 +02:00
Arne Jansen 8c51032f97 btrfs: scrub: errors in tree enumeration
due to the semantics of btrfs_search_slot the path can point to an
invalid slot when ret > 0. This condition went unnoticed, which in
turn could have led to an incomplete scrubbing.

Signed-off-by: Arne Jansen <sensille@gmx.net>
2011-06-10 12:14:13 +02:00
David Sterba 7841cb2898 btrfs: add helper for fs_info->closing
wrap checking of filesystem 'closing' flag and fix a few missing memory
barriers.

Signed-off-by: David Sterba <dsterba@suse.cz>
2011-06-04 08:11:22 -04:00
Arne Jansen e7786c3ae5 btrfs: scrub: add explicit plugging
With the removal of the implicit plugging scrub ends up doing more and
smaller I/O than necessary. This patch adds explicit plugging per chunk.

Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-06-04 08:03:46 -04:00
Arne Jansen 1bc8779349 btrfs: scrub: don't reuse bios and pages
The current scrub implementation reuses bios and pages as often as possible,
allocating them only on start and releasing them when finished. This leads
to more problems with the block layer than it's worth. The elevator gets
confused when there are more pages added to the bio than bi_size suggests.
This patch completely rips out the reuse of bios and pages and allocates
them freshly for each submit.

Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Chris Maosn <chris.mason@oracle.com>
2011-06-04 08:03:17 -04:00
Arne Jansen 00d01bc17c btrfs scrub: don't coalesce pages that are logically discontiguous
scrub_page collects several pages into one bio as long as they are physically
contiguous. As we only save one logical address for the whole bio, don't
collect pages that are physically contiguous but logically discontiguous.

Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-26 17:52:52 -04:00
Chris Mason 712673339a Merge branch 'for-chris' of git://git.kernel.org/pub/scm/linux/kernel/git/arne/btrfs-unstable-arne into inode_numbers
Conflicts:
	fs/btrfs/Makefile
	fs/btrfs/ctree.h
	fs/btrfs/volumes.h

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-23 06:30:52 -04:00
Arne Jansen 8628764e1a btrfs: add readonly flag
setting the readonly flag prevents writes in case an error is detected

Signed-off-by: Arne Jansen <sensille@gmx.net>
2011-05-12 14:48:31 +02:00
Ilya Dryomov 96e369208e btrfs scrub: make fixups sync
btrfs scrub - make fixups sync, don't reuse fixup bios

Fixups are already sync for csum failures, this patch makes them sync
for EIO case as well.

Fixups are now sharing pages with the parent sbio - instead of
allocating a separate page to do a fixup we grab the page from the sbio
buffer.

Fixup bios are no longer reused.

struct fixup is no longer needed, instead pass [sbio pointer, index].

Originally this was added to look at the possibility of sharing the code
between drive swap and scrub, but it actually fixes a serious bug in
scrub code where errors that could be corrected were ignored and
reported as uncorrectable.

btrfs scrub - restore bios properly after media errors

The current code reallocates a bio after a media error.  This is a
temporary measure introduced in v3 after a serious problem related to
bio reuse was found in v2 of scrub patchset.

Basically we did not reset bv_offset and bv_len fields of the bio_vec
structure.  They are changed in case I/O error happens, for example, at
offset 512 or 1024 into the page.  Also bi_flags field wasn't properly
setup before reusing the bio.

Signed-off-by: Arne Jansen <sensille@gmx.net>
2011-05-12 14:48:28 +02:00
Arne Jansen a2de733c78 btrfs: scrub
This adds an initial implementation for scrub. It works quite
straightforward. The usermode issues an ioctl for each device in the
fs. For each device, it enumerates the allocated device chunks. For
each chunk, the contained extents are enumerated and the data checksums
fetched. The extents are read sequentially and the checksums verified.
If an error occurs (checksum or EIO), a good copy is searched for. If
one is found, the bad copy will be rewritten.
All enumerations happen from the commit roots. During a transaction
commit, the scrubs get paused and afterwards continue from the new
roots.

This commit is based on the series originally posted to linux-btrfs
with some improvements that resulted from comments from David Sterba,
Ilya Dryomov and Jan Schmidt.

Signed-off-by: Arne Jansen <sensille@gmx.net>
2011-05-12 14:45:20 +02:00