virtio_blk: change to use __blk_end_request()

This patch converts virtio_blk to use __blk_end_request() directly
so that end_{queued|dequeued}_request() can be removed.
Related 'uptodate' argument is converted to 'error'.
Signed-off-by: NKiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

drivers/block/virtio_blk.c

@@ -47,20 +47,20 @@ static void blk_done(struct virtqueue *vq)
 
 	spin_lock_irqsave(&vblk->lock, flags);
 	while ((vbr = vblk->vq->vq_ops->get_buf(vblk->vq, &len)) != NULL) {
-		int uptodate;
+		int error;
 		switch (vbr->status) {
 		case VIRTIO_BLK_S_OK:
-			uptodate = 1;
+			error = 0;
 			break;
 		case VIRTIO_BLK_S_UNSUPP:
-			uptodate = -ENOTTY;
+			error = -ENOTTY;
 			break;
 		default:
-			uptodate = 0;
+			error = -EIO;
 			break;
 		}
 
-		end_dequeued_request(vbr->req, uptodate);
+		__blk_end_request(vbr->req, error, blk_rq_bytes(vbr->req));
 		list_del(&vbr->list);
 		mempool_free(vbr, vblk->pool);
 	}