dm: send empty barriers to targets in dm_flush

Pass empty barrier flushes to the targets in dm_flush().

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This commit is contained in:
Mikulas Patocka 2009-06-22 10:12:21 +01:00 committed by Alasdair G Kergon
parent 9015df24a8
commit 52b1fd5a27

View File

@ -164,6 +164,9 @@ struct mapped_device {
/* sysfs handle */
struct kobject kobj;
/* zero-length barrier that will be cloned and submitted to targets */
struct bio barrier_bio;
};
#define MIN_IOS 256
@ -1477,6 +1480,13 @@ static int dm_wait_for_completion(struct mapped_device *md, int interruptible)
static void dm_flush(struct mapped_device *md)
{
dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE);
bio_init(&md->barrier_bio);
md->barrier_bio.bi_bdev = md->bdev;
md->barrier_bio.bi_rw = WRITE_BARRIER;
__split_and_process_bio(md, &md->barrier_bio);
dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE);
}
static void process_barrier(struct mapped_device *md, struct bio *bio)