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, 31 deletions

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 25a96c42bdb0..fc6607acb6e4 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -611,36 +611,6 @@ static void raid10_unplug(struct request_queue *q)
         md_wakeup_thread(mddev->thread);
 }
 
-static int raid10_issue_flush(struct request_queue *q, struct gendisk *disk,
-                             sector_t *error_sector)
-{
-        mddev_t *mddev = q->queuedata;
-        conf_t *conf = mddev_to_conf(mddev);
-        int i, ret = 0;
-
-        rcu_read_lock();
-        for (i=0; i<mddev->raid_disks && ret == 0; i++) {
-                mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
-                if (rdev && !test_bit(Faulty, &rdev->flags)) {
-                        struct block_device *bdev = rdev->bdev;
-                        struct request_queue *r_queue = bdev_get_queue(bdev);
-
-                        if (!r_queue->issue_flush_fn)
-                                ret = -EOPNOTSUPP;
-                        else {
-                                atomic_inc(&rdev->nr_pending);
-                                rcu_read_unlock();
-                                ret = r_queue->issue_flush_fn(r_queue, bdev->bd_disk,
-                                                              error_sector);
-                                rdev_dec_pending(rdev, mddev);
-                                rcu_read_lock();
-                        }
-                }
-        }
-        rcu_read_unlock();
-        return ret;
-}
-
 static int raid10_congested(void *data, int bits)
 {
         mddev_t *mddev = data;
@@ -2118,7 +2088,6 @@ static int run(mddev_t *mddev)
         mddev->resync_max_sectors = size << conf->chunk_shift;
 
         mddev->queue->unplug_fn = raid10_unplug;
-        mddev->queue->issue_flush_fn = raid10_issue_flush;
         mddev->queue->backing_dev_info.congested_fn = raid10_congested;
         mddev->queue->backing_dev_info.congested_data = mddev;