diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/md/dm.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 7d9ca709433..badb7519ccc 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -750,6 +750,40 @@ static struct bio *clone_bio(struct bio *bio, sector_t sector, return clone; } +static void __flush_target(struct clone_info *ci, struct dm_target *ti, + unsigned flush_nr) +{ + struct dm_target_io *tio = alloc_tio(ci->md); + struct bio *clone; + + tio->io = ci->io; + tio->ti = ti; + + memset(&tio->info, 0, sizeof(tio->info)); + tio->info.flush_request = flush_nr; + + clone = bio_alloc_bioset(GFP_NOIO, 0, ci->md->bs); + __bio_clone(clone, ci->bio); + clone->bi_destructor = dm_bio_destructor; + + __map_bio(ti, clone, tio); +} + +static int __clone_and_map_empty_barrier(struct clone_info *ci) +{ + unsigned target_nr = 0, flush_nr; + struct dm_target *ti; + + while ((ti = dm_table_get_target(ci->map, target_nr++))) + for (flush_nr = 0; flush_nr < ti->num_flush_requests; + flush_nr++) + __flush_target(ci, ti, flush_nr); + + ci->sector_count = 0; + + return 0; +} + static int __clone_and_map(struct clone_info *ci) { struct bio *clone, *bio = ci->bio; @@ -757,6 +791,9 @@ static int __clone_and_map(struct clone_info *ci) sector_t len = 0, max; struct dm_target_io *tio; + if (unlikely(bio_empty_barrier(bio))) + return __clone_and_map_empty_barrier(ci); + ti = dm_table_find_target(ci->map, ci->sector); if (!dm_target_is_valid(ti)) return -EIO; @@ -877,6 +914,8 @@ static void __split_and_process_bio(struct mapped_device *md, struct bio *bio) ci.io->md = md; ci.sector = bio->bi_sector; ci.sector_count = bio_sectors(bio); + if (unlikely(bio_empty_barrier(bio))) + ci.sector_count = 1; ci.idx = bio->bi_idx; start_io_acct(ci.io); |