dm-clone: use blkdev_issue_flush in commit_metadata

Use blkdev_issue_flush instead of open coding it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/md/dm-clone-target.c

@@ -85,12 +85,6 @@ struct clone {
 
 	struct dm_clone_metadata *cmd;
 
-	/*
-	 * bio used to flush the destination device, before committing the
-	 * metadata.
-	 */
-	struct bio flush_bio;
-
 	/* Region hydration hash table */
 	struct hash_table_bucket *ht;
 
@@ -1155,11 +1149,7 @@ static int commit_metadata(struct clone *clone, bool *dest_dev_flushed)
 		goto out;
 	}
 
-	bio_reset(&clone->flush_bio);
-	bio_set_dev(&clone->flush_bio, clone->dest_dev->bdev);
-	clone->flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH;
-
-	r = submit_bio_wait(&clone->flush_bio);
+	r = blkdev_issue_flush(clone->dest_dev->bdev);
 	if (unlikely(r)) {
 		__metadata_operation_failed(clone, "flush destination device", r);
 		goto out;
@@ -1886,7 +1876,6 @@ static int clone_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	bio_list_init(&clone->deferred_flush_completions);
 	clone->hydration_offset = 0;
 	atomic_set(&clone->hydrations_in_flight, 0);
-	bio_init(&clone->flush_bio, NULL, 0);
 
 	clone->wq = alloc_workqueue("dm-" DM_MSG_PREFIX, WQ_MEM_RECLAIM, 0);
 	if (!clone->wq) {
@@ -1958,7 +1947,6 @@ static void clone_dtr(struct dm_target *ti)
 	struct clone *clone = ti->private;
 
 	mutex_destroy(&clone->commit_lock);
-	bio_uninit(&clone->flush_bio);
 
 	for (i = 0; i < clone->nr_ctr_args; i++)
 		kfree(clone->ctr_args[i]);