block: implement and enforce request peek/start/fetch

[mirror_ubuntu-bionic-kernel.git] / drivers / s390 / char / tape_block.c

diff --git a/drivers/s390/char/tape_block.c b/drivers/s390/char/tape_block.c
index 5d035e4939dc0df81f4c3a7ce0dc8d8ae6d3b54d..1e796767598056616ed6b3265ed27855fd77d40a 100644 (file)
--- a/drivers/s390/char/tape_block.c
+++ b/drivers/s390/char/tape_block.c
@@ -93,7 +93,7 @@ __tapeblock_end_request(struct tape_request *ccw_req, void *data)
                device->blk_data.block_position = -1;
        device->discipline->free_bread(ccw_req);
        if (!list_empty(&device->req_queue) ||
-           elv_next_request(device->blk_data.request_queue))
+           blk_peek_request(device->blk_data.request_queue))
                tapeblock_trigger_requeue(device);
 }
 
@@ -162,19 +162,16 @@ tapeblock_requeue(struct work_struct *work) {
        spin_lock_irq(&device->blk_data.request_queue_lock);
        while (
                !blk_queue_plugged(queue) &&
-               elv_next_request(queue)   &&
+               (req = blk_fetch_request(queue)) &&
                nr_queued < TAPEBLOCK_MIN_REQUEUE
        ) {
-               req = elv_next_request(queue);
                if (rq_data_dir(req) == WRITE) {
                        DBF_EVENT(1, "TBLOCK: Rejecting write request\n");
-                       blkdev_dequeue_request(req);
                        spin_unlock_irq(&device->blk_data.request_queue_lock);
                        blk_end_request_all(req, -EIO);
                        spin_lock_irq(&device->blk_data.request_queue_lock);
                        continue;
                }
-               blkdev_dequeue_request(req);
                nr_queued++;
                spin_unlock_irq(&device->blk_data.request_queue_lock);
                rc = tapeblock_start_request(device, req);