diff options
Diffstat (limited to 'drivers/md/dm.c')
| -rw-r--r-- | drivers/md/dm.c | 35 |
1 files changed, 25 insertions, 10 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index dddbca63e140..f588a6a83d80 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1420,11 +1420,11 @@ static int __send_empty_flush(struct clone_info *ci) struct dm_target *ti; /* - * Empty flush uses a statically initialized bio, &md->flush_bio, as - * the base for cloning. However, blkg association requires that a - * bdev is associated with a gendisk, which doesn't happen until the - * bdev is opened. So, blkg association is done at issue time of the - * flush rather than when the device is created in alloc_dev(). + * Empty flush uses a statically initialized bio, as the base for + * cloning. However, blkg association requires that a bdev is + * associated with a gendisk, which doesn't happen until the bdev is + * opened. So, blkg association is done at issue time of the flush + * rather than when the device is created in alloc_dev(). */ bio_set_dev(ci->bio, ci->io->md->bdev); @@ -1609,7 +1609,16 @@ static blk_qc_t __split_and_process_bio(struct mapped_device *md, init_clone_info(&ci, md, map, bio); if (bio->bi_opf & REQ_PREFLUSH) { - ci.bio = &ci.io->md->flush_bio; + struct bio flush_bio; + + /* + * Use an on-stack bio for this, it's safe since we don't + * need to reference it after submit. It's just used as + * the basis for the clone(s). + */ + bio_init(&flush_bio, NULL, 0); + flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC; + ci.bio = &flush_bio; ci.sector_count = 0; error = __send_empty_flush(&ci); /* dec_pending submits any data associated with flush */ @@ -1665,7 +1674,16 @@ static blk_qc_t __process_bio(struct mapped_device *md, init_clone_info(&ci, md, map, bio); if (bio->bi_opf & REQ_PREFLUSH) { - ci.bio = &ci.io->md->flush_bio; + struct bio flush_bio; + + /* + * Use an on-stack bio for this, it's safe since we don't + * need to reference it after submit. It's just used as + * the basis for the clone(s). + */ + bio_init(&flush_bio, NULL, 0); + flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC; + ci.bio = &flush_bio; ci.sector_count = 0; error = __send_empty_flush(&ci); /* dec_pending submits any data associated with flush */ @@ -1949,9 +1967,6 @@ static struct mapped_device *alloc_dev(int minor) if (!md->bdev) goto bad; - bio_init(&md->flush_bio, NULL, 0); - md->flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC; - dm_stats_init(&md->stats); /* Populate the mapping, nobody knows we exist yet */ |