diff --git a/drivers/md/md.h b/drivers/md/md.h
index c88b047..5be0d69 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -29,6 +29,26 @@
 typedef struct mddev_s mddev_t;
 typedef struct mdk_rdev_s mdk_rdev_t;
 
+/* generic plugging support - like that provided with request_queue,
+ * but does not require a request_queue
+ */
+struct plug_handle {
+	void			(*unplug_fn)(struct plug_handle *);
+	struct timer_list	unplug_timer;
+	struct work_struct	unplug_work;
+	unsigned long		unplug_flag;
+};
+#define	PLUGGED_FLAG 1
+void plugger_init(struct plug_handle *plug,
+		  void (*unplug_fn)(struct plug_handle *));
+void plugger_set_plug(struct plug_handle *plug);
+int plugger_remove_plug(struct plug_handle *plug);
+static inline void plugger_flush(struct plug_handle *plug)
+{
+	del_timer_sync(&plug->unplug_timer);
+	cancel_work_sync(&plug->unplug_work);
+}
+
 /*
  * MD's 'extended' device
  */