From cd15fb64ee56192760ad5c1e2ad97a65e735b18b Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Thu, 15 Jun 2017 08:39:15 -0400 Subject: Revert "dm mirror: use all available legs on multiple failures" This reverts commit 12a7cf5ba6c776a2621d8972c7d42e8d3d959d20. This commit apparently attempted to fix an issue that didn't really exist, furthermore: this commit is the source of deadlocks and crashes seen in multiple cases related to failing the primary mirror dev while syncing. Reported-by: Jonathan Brassow Signed-off-by: Mike Snitzer --- drivers/md/dm-raid1.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) (limited to 'drivers/md') diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c index e61c45047c25..4da8858856fb 100644 --- a/drivers/md/dm-raid1.c +++ b/drivers/md/dm-raid1.c @@ -145,6 +145,7 @@ static void dispatch_bios(void *context, struct bio_list *bio_list) struct dm_raid1_bio_record { struct mirror *m; + /* if details->bi_bdev == NULL, details were not saved */ struct dm_bio_details details; region_t write_region; }; @@ -1198,6 +1199,8 @@ static int mirror_map(struct dm_target *ti, struct bio *bio) struct dm_raid1_bio_record *bio_record = dm_per_bio_data(bio, sizeof(struct dm_raid1_bio_record)); + bio_record->details.bi_bdev = NULL; + if (rw == WRITE) { /* Save region for mirror_end_io() handler */ bio_record->write_region = dm_rh_bio_to_region(ms->rh, bio); @@ -1256,12 +1259,22 @@ static int mirror_end_io(struct dm_target *ti, struct bio *bio, int error) } if (error == -EOPNOTSUPP) - return error; + goto out; if ((error == -EWOULDBLOCK) && (bio->bi_opf & REQ_RAHEAD)) - return error; + goto out; if (unlikely(error)) { + if (!bio_record->details.bi_bdev) { + /* + * There wasn't enough memory to record necessary + * information for a retry or there was no other + * mirror in-sync. + */ + DMERR_LIMIT("Mirror read failed."); + return -EIO; + } + m = bio_record->m; DMERR("Mirror read failed from %s. Trying alternative device.", @@ -1277,6 +1290,7 @@ static int mirror_end_io(struct dm_target *ti, struct bio *bio, int error) bd = &bio_record->details; dm_bio_restore(bd, bio); + bio_record->details.bi_bdev = NULL; bio->bi_error = 0; queue_bio(ms, bio, rw); @@ -1285,6 +1299,9 @@ static int mirror_end_io(struct dm_target *ti, struct bio *bio, int error) DMERR("All replicated volumes dead, failing I/O"); } +out: + bio_record->details.bi_bdev = NULL; + return error; } -- cgit v1.2.3-59-g8ed1b