block: convert blkdev_issue_flush() to use empty barriers

Then we can get rid of ->issue_flush_fn() and all the driver private
implementations of that.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 0 insertions, 16 deletions

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 167765c47747..d837d37f6209 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -840,21 +840,6 @@ static int dm_request(struct request_queue *q, struct bio *bio)
         return 0;
 }
 
-static int dm_flush_all(struct request_queue *q, struct gendisk *disk,
-                        sector_t *error_sector)
-{
-        struct mapped_device *md = q->queuedata;
-        struct dm_table *map = dm_get_table(md);
-        int ret = -ENXIO;
-
-        if (map) {
-                ret = dm_table_flush_all(map);
-                dm_table_put(map);
-        }
-
-        return ret;
-}
-
 static void dm_unplug_all(struct request_queue *q)
 {
         struct mapped_device *md = q->queuedata;
@@ -1003,7 +988,6 @@ static struct mapped_device *alloc_dev(int minor)
         blk_queue_make_request(md->queue, dm_request);
         blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY);
         md->queue->unplug_fn = dm_unplug_all;
-        md->queue->issue_flush_fn = dm_flush_all;
 
         md->io_pool = mempool_create_slab_pool(MIN_IOS, _io_cache);
         if (!md->io_pool)