diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 77f37ef8ef06..617a2b3f7582 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1736,8 +1736,8 @@ out:
 
 /**
  * blkcg_schedule_throttle - this task needs to check for throttling
- * @q - the request queue IO was submitted on
- * @use_memdelay - do we charge this to memory delay for PSI
+ * @q: the request queue IO was submitted on
+ * @use_memdelay: do we charge this to memory delay for PSI
  *
  * This is called by the IO controller when we know there's delay accumulated
  * for the blkg for this task.  We do not pass the blkg because there are places
@@ -1769,8 +1769,9 @@ void blkcg_schedule_throttle(struct request_queue *q, bool use_memdelay)
 
 /**
  * blkcg_add_delay - add delay to this blkg
- * @now - the current time in nanoseconds
- * @delta - how many nanoseconds of delay to add
+ * @blkg: blkg of interest
+ * @now: the current time in nanoseconds
+ * @delta: how many nanoseconds of delay to add
  *
  * Charge @delta to the blkg's current delay accumulation.  This is used to
  * throttle tasks if an IO controller thinks we need more throttling.
diff --git a/block/blk-iolatency.c b/block/blk-iolatency.c
index 2620baa1f699..507212d75ee2 100644
--- a/block/blk-iolatency.c
+++ b/block/blk-iolatency.c
@@ -75,6 +75,7 @@
 #include <linux/blk-mq.h>
 #include "blk-rq-qos.h"
 #include "blk-stat.h"
+#include "blk.h"
 
 #define DEFAULT_SCALE_COOKIE 1000000U
 
diff --git a/block/blk-mq.c b/block/blk-mq.c
index a9c181603cbd..70b210a308c4 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -782,7 +782,6 @@ void blk_mq_add_to_requeue_list(struct request *rq, bool at_head,
 	if (kick_requeue_list)
 		blk_mq_kick_requeue_list(q);
 }
-EXPORT_SYMBOL(blk_mq_add_to_requeue_list);
 
 void blk_mq_kick_requeue_list(struct request_queue *q)
 {
@@ -1093,8 +1092,7 @@ static bool blk_mq_mark_tag_wait(struct blk_mq_hw_ctx *hctx,
 	bool ret;
 
 	if (!(hctx->flags & BLK_MQ_F_TAG_SHARED)) {
-		if (!test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state))
-			set_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state);
+		blk_mq_sched_mark_restart_hctx(hctx);
 
 		/*
 		 * It's possible that a tag was freed in the window between the
@@ -2857,7 +2855,7 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
 	/*
 	 * Default to classic polling
 	 */
-	q->poll_nsec = -1;
+	q->poll_nsec = BLK_MQ_POLL_CLASSIC;
 
 	blk_mq_init_cpu_queues(q, set->nr_hw_queues);
 	blk_mq_add_queue_tag_set(set, q);
@@ -3392,7 +3390,7 @@ static bool blk_mq_poll_hybrid(struct request_queue *q,
 {
 	struct request *rq;
 
-	if (q->poll_nsec == -1)
+	if (q->poll_nsec == BLK_MQ_POLL_CLASSIC)
 		return false;
 
 	if (!blk_qc_t_is_internal(cookie))
diff --git a/block/blk-mq.h b/block/blk-mq.h
index c11353a3749d..0ed8e5a8729f 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -41,6 +41,8 @@ void blk_mq_free_queue(struct request_queue *q);
 int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
 void blk_mq_wake_waiters(struct request_queue *q);
 bool blk_mq_dispatch_rq_list(struct request_queue *, struct list_head *, bool);
+void blk_mq_add_to_requeue_list(struct request *rq, bool at_head,
+				bool kick_requeue_list);
 void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);
 bool blk_mq_get_driver_tag(struct request *rq);
 struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 59685918167e..422327089e0f 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -360,8 +360,8 @@ static ssize_t queue_poll_delay_show(struct request_queue *q, char *page)
 {
 	int val;
 
-	if (q->poll_nsec == -1)
-		val = -1;
+	if (q->poll_nsec == BLK_MQ_POLL_CLASSIC)
+		val = BLK_MQ_POLL_CLASSIC;
 	else
 		val = q->poll_nsec / 1000;
 
@@ -380,10 +380,12 @@ static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page,
 	if (err < 0)
 		return err;
 
-	if (val == -1)
-		q->poll_nsec = -1;
-	else
+	if (val == BLK_MQ_POLL_CLASSIC)
+		q->poll_nsec = BLK_MQ_POLL_CLASSIC;
+	else if (val >= 0)
 		q->poll_nsec = val * 1000;
+	else
+		return -EINVAL;
 
 	return count;
 }
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 1e6edd568214..bf1c61cab8eb 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -656,7 +656,7 @@ static int loop_validate_file(struct file *file, struct block_device *bdev)
 			return -EBADF;
 
 		l = f->f_mapping->host->i_bdev->bd_disk->private_data;
-		if (l->lo_state == Lo_unbound) {
+		if (l->lo_state != Lo_bound) {
 			return -EINVAL;
 		}
 		f = l->lo_backing_file;
diff --git a/drivers/block/paride/pcd.c b/drivers/block/paride/pcd.c
index 96670eefaeb2..377a694dc228 100644
--- a/drivers/block/paride/pcd.c
+++ b/drivers/block/paride/pcd.c
@@ -749,8 +749,12 @@ static int pcd_detect(void)
 		return 0;
 
 	printk("%s: No CD-ROM drive found\n", name);
-	for (unit = 0, cd = pcd; unit < PCD_UNITS; unit++, cd++)
+	for (unit = 0, cd = pcd; unit < PCD_UNITS; unit++, cd++) {
+		blk_cleanup_queue(cd->disk->queue);
+		cd->disk->queue = NULL;
+		blk_mq_free_tag_set(&cd->tag_set);
 		put_disk(cd->disk);
+	}
 	pi_unregister_driver(par_drv);
 	return -1;
 }
diff --git a/drivers/block/paride/pf.c b/drivers/block/paride/pf.c
index e92e7a8eeeb2..103b617cdc31 100644
--- a/drivers/block/paride/pf.c
+++ b/drivers/block/paride/pf.c
@@ -761,8 +761,12 @@ static int pf_detect(void)
 		return 0;
 
 	printk("%s: No ATAPI disk detected\n", name);
-	for (pf = units, unit = 0; unit < PF_UNITS; pf++, unit++)
+	for (pf = units, unit = 0; unit < PF_UNITS; pf++, unit++) {
+		blk_cleanup_queue(pf->disk->queue);
+		pf->disk->queue = NULL;
+		blk_mq_free_tag_set(&pf->tag_set);
 		put_disk(pf->disk);
+	}
 	pi_unregister_driver(par_drv);
 	return -1;
 }
@@ -1047,13 +1051,15 @@ static void __exit pf_exit(void)
 	int unit;
 	unregister_blkdev(major, name);
 	for (pf = units, unit = 0; unit < PF_UNITS; pf++, unit++) {
-		if (!pf->present)
-			continue;
-		del_gendisk(pf->disk);
+		if (pf->present)
+			del_gendisk(pf->disk);
+
 		blk_cleanup_queue(pf->disk->queue);
 		blk_mq_free_tag_set(&pf->tag_set);
 		put_disk(pf->disk);
-		pi_release(pf->pi);
+
+		if (pf->present)
+			pi_release(pf->pi);
 	}
 }
 
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index b0c814bcc7e3..cb2aa7ecafff 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -57,7 +57,6 @@ struct blk_mq_hw_ctx {
 	unsigned int		queue_num;
 
 	atomic_t		nr_active;
-	unsigned int		nr_expired;
 
 	struct hlist_node	cpuhp_dead;
 	struct kobject		kobj;
@@ -300,8 +299,6 @@ void blk_mq_end_request(struct request *rq, blk_status_t error);
 void __blk_mq_end_request(struct request *rq, blk_status_t error);
 
 void blk_mq_requeue_request(struct request *rq, bool kick_requeue_list);
-void blk_mq_add_to_requeue_list(struct request *rq, bool at_head,
-				bool kick_requeue_list);
 void blk_mq_kick_requeue_list(struct request_queue *q);
 void blk_mq_delay_kick_requeue_list(struct request_queue *q, unsigned long msecs);
 bool blk_mq_complete_request(struct request *rq);
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 0de92b29f589..5c58a3b2bf00 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -50,6 +50,9 @@ struct blk_stat_callback;
 /* Must be consistent with blk_mq_poll_stats_bkt() */
 #define BLK_MQ_POLL_STATS_BKTS 16
 
+/* Doing classic polling */
+#define BLK_MQ_POLL_CLASSIC -1
+
 /*
  * Maximum number of blkcg policies allowed to be registered concurrently.
  * Defined here to simplify include dependency.
diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h
index 14d558146aea..20f3e3f029b9 100644
--- a/include/linux/sbitmap.h
+++ b/include/linux/sbitmap.h
@@ -330,7 +330,7 @@ static inline void sbitmap_clear_bit(struct sbitmap *sb, unsigned int bitnr)
 /*
  * This one is special, since it doesn't actually clear the bit, rather it
  * sets the corresponding bit in the ->cleared mask instead. Paired with
- * the caller doing sbitmap_batch_clear() if a given index is full, which
+ * the caller doing sbitmap_deferred_clear() if a given index is full, which
  * will clear the previously freed entries in the corresponding ->word.
  */
 static inline void sbitmap_deferred_clear_bit(struct sbitmap *sb, unsigned int bitnr)