diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c
index 909f0517f8..0d0e807216 100644
--- a/block/dirty-bitmap.c
+++ b/block/dirty-bitmap.c
@@ -234,6 +234,14 @@ int bdrv_dirty_bitmap_create_successor(BlockDriverState *bs,
     return 0;
 }
 
+/* Called with BQL taken. */
+void bdrv_dirty_bitmap_enable_successor(BdrvDirtyBitmap *bitmap)
+{
+    qemu_mutex_lock(bitmap->mutex);
+    bdrv_enable_dirty_bitmap(bitmap->successor);
+    qemu_mutex_unlock(bitmap->mutex);
+}
+
 /**
  * For a bitmap with a successor, yield our name to the successor,
  * delete the old bitmap, and return a handle to the new bitmap.
diff --git a/include/block/dirty-bitmap.h b/include/block/dirty-bitmap.h
index 09efec609f..e0ebc96b01 100644
--- a/include/block/dirty-bitmap.h
+++ b/include/block/dirty-bitmap.h
@@ -21,6 +21,7 @@ BdrvDirtyBitmap *bdrv_dirty_bitmap_abdicate(BlockDriverState *bs,
 BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,
                                            BdrvDirtyBitmap *bitmap,
                                            Error **errp);
+void bdrv_dirty_bitmap_enable_successor(BdrvDirtyBitmap *bitmap);
 BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs,
                                         const char *name);
 void bdrv_dirty_bitmap_make_anon(BdrvDirtyBitmap *bitmap);