Merge tag 'spi-nor/for-5.5' into mtd/next

SPI NOR core changes:
- introduce 'struct spi_nor_controller_ops',
- clean the Register Operations methods,
- use dev_dbg insted of dev_err for low level info,
- fix retlen handling in sst_write(),
- fix silent truncations in spi_nor_read and spi_nor_read_raw(),
- fix the clearing of QE bit on lock()/unlock(),
- rework the disabling of the block write protection,
- rework the Quad Enable methods,
- make sure nor->spimem and nor->controller_ops are mutually exclusive,
- set default Quad Enable method for ISSI flashes,
- add support for few flashes.

SPI NOR controller drivers changes:
- intel-spi:
	- support chips without software sequencer,
	- add support for Intel Cannon Lake and Intel Comet Lake-H flashes.

1 files changed, 9 insertions, 3 deletions

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 6e3b15f70cd7..ec791156e9cc 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1992,10 +1992,14 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
 		/* bypass scheduler for flush rq */
 		blk_insert_flush(rq);
 		blk_mq_run_hw_queue(data.hctx, true);
-	} else if (plug && (q->nr_hw_queues == 1 || q->mq_ops->commit_rqs)) {
+	} else if (plug && (q->nr_hw_queues == 1 || q->mq_ops->commit_rqs ||
+				!blk_queue_nonrot(q))) {
 		/*
 		 * Use plugging if we have a ->commit_rqs() hook as well, as
 		 * we know the driver uses bd->last in a smart fashion.
+		 *
+		 * Use normal plugging if this disk is slow HDD, as sequential
+		 * IO may benefit a lot from plug merging.
 		 */
 		unsigned int request_count = plug->rq_count;
 		struct request *last = NULL;
@@ -2012,6 +2016,8 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
 		}
 
 		blk_add_rq_to_plug(plug, rq);
+	} else if (q->elevator) {
+		blk_mq_sched_insert_request(rq, false, true, true);
 	} else if (plug && !blk_queue_nomerges(q)) {
 		/*
 		 * We do limited plugging. If the bio can be merged, do that.
@@ -2035,8 +2041,8 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
 			blk_mq_try_issue_directly(data.hctx, same_queue_rq,
 					&cookie);
 		}
-	} else if ((q->nr_hw_queues > 1 && is_sync) || (!q->elevator &&
-			!data.hctx->dispatch_busy)) {
+	} else if ((q->nr_hw_queues > 1 && is_sync) ||
+			!data.hctx->dispatch_busy) {
 		blk_mq_try_issue_directly(data.hctx, rq, &cookie);
 	} else {
 		blk_mq_sched_insert_request(rq, false, true, true);