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/raid5.c b/drivers/md/raid5.c
index caaca9e178bc..8ee181a01f52 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -3204,36 +3204,6 @@ static void raid5_unplug_device(struct request_queue *q)
         unplug_slaves(mddev);
 }
 
-static int raid5_issue_flush(struct request_queue *q, struct gendisk *disk,
-                             sector_t *error_sector)
-{
-        mddev_t *mddev = q->queuedata;
-        raid5_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->disks[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 raid5_congested(void *data, int bits)
 {
         mddev_t *mddev = data;
@@ -4263,7 +4233,6 @@ static int run(mddev_t *mddev)
                        mdname(mddev));
 
         mddev->queue->unplug_fn = raid5_unplug_device;
-        mddev->queue->issue_flush_fn = raid5_issue_flush;
         mddev->queue->backing_dev_info.congested_data = mddev;
         mddev->queue->backing_dev_info.congested_fn = raid5_congested;