1 files changed, 5 insertions, 28 deletions

diff --git a/block/blk-mq.c b/block/blk-mq.c
index d020fffbbcc6..23a53b67cf0d 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1698,15 +1698,6 @@ static blk_status_t __blk_mq_issue_directly(struct blk_mq_hw_ctx *hctx,
 		break;
 	case BLK_STS_RESOURCE:
 	case BLK_STS_DEV_RESOURCE:
-		/*
-		 * If direct dispatch fails, we cannot allow any merging on
-		 * this IO. Drivers (like SCSI) may have set up permanent state
-		 * for this request, like SG tables and mappings, and if we
-		 * merge to it later on then we'll still only do IO to the
-		 * original part.
-		 */
-		rq->cmd_flags |= REQ_NOMERGE;
-
 		blk_mq_update_dispatch_busy(hctx, true);
 		__blk_mq_requeue_request(rq);
 		break;
@@ -1719,18 +1710,6 @@ static blk_status_t __blk_mq_issue_directly(struct blk_mq_hw_ctx *hctx,
 	return ret;
 }
 
-/*
- * Don't allow direct dispatch of anything but regular reads/writes,
- * as some of the other commands can potentially share request space
- * with data we need for the IO scheduler. If we attempt a direct dispatch
- * on those and fail, we can't safely add it to the scheduler afterwards
- * without potentially overwriting data that the driver has already written.
- */
-static bool blk_rq_can_direct_dispatch(struct request *rq)
-{
-	return req_op(rq) == REQ_OP_READ || req_op(rq) == REQ_OP_WRITE;
-}
-
 static blk_status_t __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
 						struct request *rq,
 						blk_qc_t *cookie,
@@ -1752,7 +1731,7 @@ static blk_status_t __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
 		goto insert;
 	}
 
-	if (!blk_rq_can_direct_dispatch(rq) || (q->elevator && !bypass_insert))
+	if (q->elevator && !bypass_insert)
 		goto insert;
 
 	if (!blk_mq_get_dispatch_budget(hctx))
@@ -1768,7 +1747,7 @@ insert:
 	if (bypass_insert)
 		return BLK_STS_RESOURCE;
 
-	blk_mq_sched_insert_request(rq, false, run_queue, false);
+	blk_mq_request_bypass_insert(rq, run_queue);
 	return BLK_STS_OK;
 }
 
@@ -1784,7 +1763,7 @@ static void blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
 
 	ret = __blk_mq_try_issue_directly(hctx, rq, cookie, false);
 	if (ret == BLK_STS_RESOURCE || ret == BLK_STS_DEV_RESOURCE)
-		blk_mq_sched_insert_request(rq, false, true, false);
+		blk_mq_request_bypass_insert(rq, true);
 	else if (ret != BLK_STS_OK)
 		blk_mq_end_request(rq, ret);
 
@@ -1814,15 +1793,13 @@ void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx,
 		struct request *rq = list_first_entry(list, struct request,
 				queuelist);
 
-		if (!blk_rq_can_direct_dispatch(rq))
-			break;
-
 		list_del_init(&rq->queuelist);
 		ret = blk_mq_request_issue_directly(rq);
 		if (ret != BLK_STS_OK) {
 			if (ret == BLK_STS_RESOURCE ||
 					ret == BLK_STS_DEV_RESOURCE) {
-				list_add(&rq->queuelist, list);
+				blk_mq_request_bypass_insert(rq,
+							list_empty(list));
 				break;
 			}
 			blk_mq_end_request(rq, ret);