dm: rename DM_TYPE_MQ_REQUEST_BASED to DM_TYPE_REQUEST_BASED

Now that request-based DM is only using blk-mq, there is no need to
differentiate between legacy "rq" and new "mq".  We're back to a single
request-based DM -- and there was much rejoicing!
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

drivers/md/dm-mpath.c

@@ -203,7 +203,7 @@ static struct multipath *alloc_multipath(struct dm_target *ti)
 static int alloc_multipath_stage2(struct dm_target *ti, struct multipath *m)
 {
 	if (m->queue_mode == DM_TYPE_NONE) {
-		m->queue_mode = DM_TYPE_MQ_REQUEST_BASED;
+		m->queue_mode = DM_TYPE_REQUEST_BASED;
 	} else if (m->queue_mode == DM_TYPE_BIO_BASED) {
 		INIT_WORK(&m->process_queued_bios, process_queued_bios);
 		/*
@@ -658,7 +658,7 @@ static int multipath_map_bio(struct dm_target *ti, struct bio *bio)
 
 static void process_queued_io_list(struct multipath *m)
 {
-	if (m->queue_mode == DM_TYPE_MQ_REQUEST_BASED)
+	if (m->queue_mode == DM_TYPE_REQUEST_BASED)
 		dm_mq_kick_requeue_list(dm_table_get_md(m->ti->table));
 	else if (m->queue_mode == DM_TYPE_BIO_BASED)
 		queue_work(kmultipathd, &m->process_queued_bios);
@@ -1079,10 +1079,9 @@ static int parse_features(struct dm_arg_set *as, struct multipath *m)
 
 			if (!strcasecmp(queue_mode_name, "bio"))
 				m->queue_mode = DM_TYPE_BIO_BASED;
-			else if (!strcasecmp(queue_mode_name, "rq"))
+			else if (!strcasecmp(queue_mode_name, "rq") ||
+				 !strcasecmp(queue_mode_name, "mq"))
 				m->queue_mode = DM_TYPE_REQUEST_BASED;
-			else if (!strcasecmp(queue_mode_name, "mq"))
-				m->queue_mode = DM_TYPE_MQ_REQUEST_BASED;
 			else {
 				ti->error = "Unknown 'queue_mode' requested";
 				r = -EINVAL;
@@ -1716,9 +1715,6 @@ static void multipath_status(struct dm_target *ti, status_type_t type,
 			case DM_TYPE_BIO_BASED:
 				DMEMIT("queue_mode bio ");
 				break;
-			case DM_TYPE_MQ_REQUEST_BASED:
-				DMEMIT("queue_mode mq ");
-				break;
 			default:
 				WARN_ON_ONCE(true);
 				break;
@@ -1962,7 +1958,7 @@ static int multipath_busy(struct dm_target *ti)
 
 	/* no paths available, for blk-mq: rely on IO mapping to delay requeue */
 	if (!atomic_read(&m->nr_valid_paths) && test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags))
-		return (m->queue_mode != DM_TYPE_MQ_REQUEST_BASED);
+		return (m->queue_mode != DM_TYPE_REQUEST_BASED);
 
 	/* Guess which priority_group will be used at next mapping time */
 	pg = READ_ONCE(m->current_pg);

drivers/md/dm-table.c

@@ -871,8 +871,7 @@ static bool __table_type_bio_based(enum dm_queue_mode table_type)
 
 static bool __table_type_request_based(enum dm_queue_mode table_type)
 {
-	return (table_type == DM_TYPE_REQUEST_BASED ||
-		table_type == DM_TYPE_MQ_REQUEST_BASED);
+	return table_type == DM_TYPE_REQUEST_BASED;
 }
 
 void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type)
@@ -986,10 +985,6 @@ static int dm_table_determine_type(struct dm_table *t)
 
 	BUG_ON(!request_based); /* No targets in this table */
 
-	/*
-	 * The only way to establish DM_TYPE_MQ_REQUEST_BASED is by
-	 * having a compatible target use dm_table_set_type.
-	 */
 	t->type = DM_TYPE_REQUEST_BASED;
 
 verify_rq_based:

drivers/md/dm.c

@@ -2213,7 +2213,6 @@ int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t)
 
 	switch (type) {
 	case DM_TYPE_REQUEST_BASED:
-	case DM_TYPE_MQ_REQUEST_BASED:
 		r = dm_mq_init_request_queue(md, t);
 		if (r) {
 			DMERR("Cannot initialize queue for request-based dm-mq mapped device");
@@ -2946,7 +2945,6 @@ struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_qu
 			goto out;
 		break;
 	case DM_TYPE_REQUEST_BASED:
-	case DM_TYPE_MQ_REQUEST_BASED:
 		pool_size = max(dm_get_reserved_rq_based_ios(), min_pool_size);
 		front_pad = offsetof(struct dm_rq_clone_bio_info, clone);
 		/* per_io_data_size is used for blk-mq pdu at queue allocation */

include/linux/device-mapper.h

@@ -26,9 +26,8 @@ enum dm_queue_mode {
 	DM_TYPE_NONE		 = 0,
 	DM_TYPE_BIO_BASED	 = 1,
 	DM_TYPE_REQUEST_BASED	 = 2,
-	DM_TYPE_MQ_REQUEST_BASED = 3,
-	DM_TYPE_DAX_BIO_BASED	 = 4,
-	DM_TYPE_NVME_BIO_BASED	 = 5,
+	DM_TYPE_DAX_BIO_BASED	 = 3,
+	DM_TYPE_NVME_BIO_BASED	 = 4,
 };
 
 typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE } status_type_t;