diff --git a/drivers/md/md.c b/drivers/md/md.c
index d00ceffb881299f8e96bf6704424044ea91fe33b..6bc446686eefdb380aeb6b025c69bd6c52be258b 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -404,6 +404,10 @@ static DEFINE_SPINLOCK(all_mddevs_lock);
 		_tmp = _tmp->next;})					\
 		)
 
+static bool is_md_suspended(struct mddev *mddev)
+{
+	return percpu_ref_is_dying(&mddev->active_io);
+}
 /* Rather than calling directly into the personality make_request function,
  * IO requests come here first so that we can check if the device is
  * being suspended pending a reconfiguration.
@@ -413,7 +417,7 @@ static DEFINE_SPINLOCK(all_mddevs_lock);
  */
 static bool is_suspended(struct mddev *mddev, struct bio *bio)
 {
-	if (mddev->suspended)
+	if (is_md_suspended(mddev))
 		return true;
 	if (bio_data_dir(bio) != WRITE)
 		return false;
@@ -429,7 +433,6 @@ static bool is_suspended(struct mddev *mddev, struct bio *bio)
 void md_handle_request(struct mddev *mddev, struct bio *bio)
 {
 check_suspended:
-	rcu_read_lock();
 	if (is_suspended(mddev, bio)) {
 		DEFINE_WAIT(__wait);
 		for (;;) {
@@ -437,23 +440,19 @@ void md_handle_request(struct mddev *mddev, struct bio *bio)
 					TASK_UNINTERRUPTIBLE);
 			if (!is_suspended(mddev, bio))
 				break;
-			rcu_read_unlock();
 			schedule();
-			rcu_read_lock();
 		}
 		finish_wait(&mddev->sb_wait, &__wait);
 	}
-	atomic_inc(&mddev->active_io);
-	rcu_read_unlock();
+	if (!percpu_ref_tryget_live(&mddev->active_io))
+		goto check_suspended;
 
 	if (!mddev->pers->make_request(mddev, bio)) {
-		atomic_dec(&mddev->active_io);
-		wake_up(&mddev->sb_wait);
+		percpu_ref_put(&mddev->active_io);
 		goto check_suspended;
 	}
 
-	if (atomic_dec_and_test(&mddev->active_io) && mddev->suspended)
-		wake_up(&mddev->sb_wait);
+	percpu_ref_put(&mddev->active_io);
 }
 EXPORT_SYMBOL(md_handle_request);
 
@@ -503,11 +502,10 @@ void mddev_suspend(struct mddev *mddev)
 	WARN_ON_ONCE(thread && current == thread->tsk);
 	if (mddev->suspended++)
 		return;
-	synchronize_rcu();
 	wake_up(&mddev->sb_wait);
 	set_bit(MD_ALLOW_SB_UPDATE, &mddev->flags);
-	smp_mb__after_atomic();
-	wait_event(mddev->sb_wait, atomic_read(&mddev->active_io) == 0);
+	percpu_ref_kill(&mddev->active_io);
+	wait_event(mddev->sb_wait, percpu_ref_is_zero(&mddev->active_io));
 	mddev->pers->quiesce(mddev, 1);
 	clear_bit_unlock(MD_ALLOW_SB_UPDATE, &mddev->flags);
 	wait_event(mddev->sb_wait, !test_bit(MD_UPDATING_SB, &mddev->flags));
@@ -527,6 +525,7 @@ void mddev_resume(struct mddev *mddev)
 	/* entred the memalloc scope from mddev_suspend() */
 	memalloc_noio_restore(mddev->noio_flag);
 
+	percpu_ref_resurrect(&mddev->active_io);
 	wake_up(&mddev->sb_wait);
 	mddev->pers->quiesce(mddev, 0);
 
@@ -627,7 +626,6 @@ void mddev_init(struct mddev *mddev)
 	timer_setup(&mddev->safemode_timer, md_safemode_timeout, 0);
 	atomic_set(&mddev->active, 1);
 	atomic_set(&mddev->openers, 0);
-	atomic_set(&mddev->active_io, 0);
 	atomic_set(&mddev->sync_seq, 0);
 	spin_lock_init(&mddev->lock);
 	init_waitqueue_head(&mddev->sb_wait);
@@ -5656,6 +5654,7 @@ static void md_free(struct kobject *ko)
 	blk_cleanup_disk(mddev->gendisk);
 
 	percpu_ref_exit(&mddev->writes_pending);
+	percpu_ref_exit(&mddev->active_io);
 
 	bioset_exit(&mddev->bio_set);
 	bioset_exit(&mddev->sync_set);
@@ -5864,6 +5863,12 @@ static void md_safemode_timeout(struct timer_list *t)
 }
 
 static int start_dirty_degraded;
+static void active_io_release(struct percpu_ref *ref)
+{
+	struct mddev *mddev = container_of(ref, struct mddev, active_io);
+
+	wake_up(&mddev->sb_wait);
+}
 
 int md_run(struct mddev *mddev)
 {
@@ -5944,10 +5949,15 @@ int md_run(struct mddev *mddev)
 		sysfs_notify_dirent_safe(rdev->sysfs_state);
 	}
 
+	err = percpu_ref_init(&mddev->active_io, active_io_release,
+				PERCPU_REF_ALLOW_REINIT, GFP_KERNEL);
+	if (err)
+		return err;
+
 	if (!bioset_initialized(&mddev->bio_set)) {
 		err = bioset_init(&mddev->bio_set, BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS);
 		if (err)
-			return err;
+			goto exit_active_io;
 	}
 	if (!bioset_initialized(&mddev->sync_set)) {
 		err = bioset_init(&mddev->sync_set, BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS);
@@ -6141,6 +6151,8 @@ int md_run(struct mddev *mddev)
 	bioset_exit(&mddev->sync_set);
 exit_bio_set:
 	bioset_exit(&mddev->bio_set);
+exit_active_io:
+	percpu_ref_exit(&mddev->active_io);
 	return err;
 }
 EXPORT_SYMBOL_GPL(md_run);
@@ -6329,7 +6341,7 @@ EXPORT_SYMBOL_GPL(md_stop_writes);
 static void mddev_detach(struct mddev *mddev)
 {
 	md_bitmap_wait_behind_writes(mddev);
-	if (mddev->pers && mddev->pers->quiesce && !mddev->suspended) {
+	if (mddev->pers && mddev->pers->quiesce && !is_md_suspended(mddev)) {
 		mddev->pers->quiesce(mddev, 1);
 		mddev->pers->quiesce(mddev, 0);
 	}
@@ -6367,6 +6379,7 @@ void md_stop(struct mddev *mddev)
 	 */
 	__md_stop_writes(mddev);
 	__md_stop(mddev);
+	percpu_ref_exit(&mddev->active_io);
 	bioset_exit(&mddev->bio_set);
 	bioset_exit(&mddev->sync_set);
 	bioset_exit(&mddev->io_acct_set);
@@ -8641,7 +8654,7 @@ bool md_write_start(struct mddev *mddev, struct bio *bi)
 		return true;
 	wait_event(mddev->sb_wait,
 		   !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags) ||
-		   mddev->suspended);
+		   is_md_suspended(mddev));
 	if (test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags)) {
 		percpu_ref_put(&mddev->writes_pending);
 		return false;
@@ -9323,7 +9336,7 @@ void md_check_recovery(struct mddev *mddev)
 		wake_up(&mddev->sb_wait);
 	}
 
-	if (mddev->suspended)
+	if (is_md_suspended(mddev))
 		return;
 
 	if (mddev->bitmap)
diff --git a/drivers/md/md.h b/drivers/md/md.h
index e13d3654aef57ecc213e098aa11897cf1341a83e..34124ed86358c6c3b59b119576cd23c59d2490e8 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -309,7 +309,7 @@ struct mddev {
 	unsigned long			sb_flags;
 
 	int				suspended;
-	atomic_t			active_io;
+	struct percpu_ref		active_io;
 	int				ro;
 	int				sysfs_active; /* set when sysfs deletes
 						       * are happening, so run/