diff --git a/mm/swapfile.c b/mm/swapfile.c
index ecb069e..f5ccc47 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -574,6 +574,7 @@
 
 	/* free if no reference */
 	if (!usage) {
+		struct gendisk *disk = p->bdev->bd_disk;
 		if (offset < p->lowest_bit)
 			p->lowest_bit = offset;
 		if (offset > p->highest_bit)
@@ -583,6 +584,9 @@
 			swap_list.next = p->type;
 		nr_swap_pages++;
 		p->inuse_pages--;
+		if ((p->flags & SWP_BLKDEV) &&
+				disk->fops->swap_slot_free_notify)
+			disk->fops->swap_slot_free_notify(p->bdev, offset);
 	}
 
 	return usage;