diff --git a/block/blk-core.c b/block/blk-core.c
index 26d1ab95b91e..a33e47731806 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -45,6 +45,7 @@
 #include <trace/events/block.h>
 
 #include "blk.h"
+#include "blk-mq-debugfs.h"
 #include "blk-mq-sched.h"
 #include "blk-pm.h"
 #include "blk-cgroup.h"
@@ -1279,6 +1280,7 @@ int __init blk_dev_init(void)
 	blk_requestq_cachep = KMEM_CACHE(request_queue, SLAB_PANIC);
 
 	blk_debugfs_root = debugfs_create_dir("block", NULL);
+	blk_mq_debugfs_init();
 
 	return 0;
 }
diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
index 5463697a8442..1c5ade59c081 100644
--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c
@@ -829,3 +829,11 @@ void blk_mq_debugfs_unregister_sched_hctx(struct blk_mq_hw_ctx *hctx)
 	debugfs_remove_recursive(hctx->sched_debugfs_dir);
 	hctx->sched_debugfs_dir = NULL;
 }
+DEFINE_DEBUGFS_ATTRIBUTE(blk_sub_page_limit_queues_fops,
+			blk_sub_page_limit_queues_get, NULL, "%llu\n");
+
+void blk_mq_debugfs_init(void)
+{
+	debugfs_create_file("sub_page_limit_queues", 0400, blk_debugfs_root,
+			    NULL, &blk_sub_page_limit_queues_fops);
+}
diff --git a/block/blk-mq-debugfs.h b/block/blk-mq-debugfs.h
index c80e453e3014..0d1d18177946 100644
--- a/block/blk-mq-debugfs.h
+++ b/block/blk-mq-debugfs.h
@@ -17,6 +17,7 @@ struct blk_mq_debugfs_attr {
 	const struct seq_operations *seq_ops;
 };
 
+void blk_mq_debugfs_init(void);
 int __blk_mq_debugfs_rq_show(struct seq_file *m, struct request *rq);
 int blk_mq_debugfs_rq_show(struct seq_file *m, void *v);
 
@@ -36,6 +37,10 @@ void blk_mq_debugfs_unregister_sched_hctx(struct blk_mq_hw_ctx *hctx);
 void blk_mq_debugfs_register_rqos(struct rq_qos *rqos);
 void blk_mq_debugfs_unregister_rqos(struct rq_qos *rqos);
 #else
+static inline void blk_mq_debugfs_init(void)
+{
+}
+
 static inline void blk_mq_debugfs_register(struct request_queue *q)
 {
 }
diff --git a/block/blk-settings.c b/block/blk-settings.c
index 2d6555f05cc8..4e4c3b52b67a 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -225,6 +225,14 @@ unsupported:
 	lim->atomic_write_unit_max = 0;
 }
 
+/* For debugfs. */
+int blk_sub_page_limit_queues_get(void *data, u64 *val)
+{
+	*val = READ_ONCE(blk_nr_sub_page_limit_queues);
+
+	return 0;
+}
+
 /**
  * blk_enable_sub_page_limits - enable support for limits below the page size
  * @lim: request queue limits for which to enable support of these features.
diff --git a/block/blk.h b/block/blk.h
index 5fa343b8cb12..183446bc7d77 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -44,12 +44,12 @@ bool __blk_freeze_queue_start(struct request_queue *q,
 int __bio_queue_enter(struct request_queue *q, struct bio *bio);
 void submit_bio_noacct_nocheck(struct bio *bio);
 void bio_await_chain(struct bio *bio);
-
 static inline bool blk_queue_sub_page_limits(const struct queue_limits *lim)
 {
 	return static_branch_unlikely(&blk_sub_page_limits) &&
 		lim->sub_page_limits;
 }
+int blk_sub_page_limit_queues_get(void *data, u64 *val);
 void blk_disable_sub_page_limits(struct queue_limits *q);
 static inline bool blk_try_enter_queue(struct request_queue *q, bool pm)
 {