diff options
| author | NeilBrown <neilb@suse.de> | 2013-07-16 16:50:47 +1000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-07-25 14:07:28 -0700 |
| commit | 2dc04d3333049098691eb652e06d52fbd80771d2 (patch) | |
| tree | 368daf6f090dbbb6402bcbcc5c287c8254617cbf | |
| parent | 4b5c14511c401edf5ea78e2592c7043456deb595 (diff) | |
md/raid10: fix two problems with RAID10 resync.
commit 7bb23c4934059c64cbee2e41d5d24ce122285176 upstream.
1/ When an different between blocks is found, data is copied from
one bio to the other. However bv_len is used as the length to
copy and this could be zero. So use r10_bio->sectors to calculate
length instead.
Using bv_len was probably always a bit dubious, but the introduction
of bio_advance made it much more likely to be a problem.
2/ When preparing some blocks for sync, we don't set BIO_UPTODATE
except on bios that we schedule for a read. This ensures that
missing/failed devices don't confuse the loop at the top of
sync_request write.
Commit 8be185f2c9d54d6 "raid10: Use bio_reset()"
removed a loop which set BIO_UPTDATE on all appropriate bios.
So we need to re-add that flag.
These bugs were introduced in 3.10, so this patch is suitable for
3.10-stable, and can remove a potential for data corruption.
Reported-by: Brassow Jonathan <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/md/raid10.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index d7bad6bc46d..d61eb7ea0d8 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -2075,11 +2075,17 @@ static void sync_request_write(struct mddev *mddev, struct r10bio *r10_bio) * both 'first' and 'i', so we just compare them. * All vec entries are PAGE_SIZE; */ - for (j = 0; j < vcnt; j++) + int sectors = r10_bio->sectors; + for (j = 0; j < vcnt; j++) { + int len = PAGE_SIZE; + if (sectors < (len / 512)) + len = sectors * 512; if (memcmp(page_address(fbio->bi_io_vec[j].bv_page), page_address(tbio->bi_io_vec[j].bv_page), - fbio->bi_io_vec[j].bv_len)) + len)) break; + sectors -= len/512; + } if (j == vcnt) continue; atomic64_add(r10_bio->sectors, &mddev->resync_mismatches); @@ -3385,6 +3391,7 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, if (bio->bi_end_io == end_sync_read) { md_sync_acct(bio->bi_bdev, nr_sectors); + set_bit(BIO_UPTODATE, &bio->bi_flags); generic_make_request(bio); } } |