drbd: Implemented conn_lowest_conn()

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

drivers/block/drbd/drbd_nl.c

@@ -1590,7 +1590,7 @@ int drbd_adm_attach(struct sk_buff *skb, struct genl_info *info)
 
 static int adm_detach(struct drbd_conf *mdev)
 {
-	enum drbd_ret_code retcode;
+	enum drbd_state_rv retcode;
 	drbd_suspend_io(mdev); /* so no-one is stuck in drbd_al_begin_io */
 	retcode = drbd_request_state(mdev, NS(disk, D_DISKLESS));
 	wait_event(mdev->misc_wait,

drivers/block/drbd/drbd_state.c

@@ -133,6 +133,18 @@ enum drbd_disk_state conn_highest_pdsk(struct drbd_tconn *tconn)
 	return ds;
 }
 
+enum drbd_conns conn_lowest_conn(struct drbd_tconn *tconn)
+{
+	enum drbd_conns conn = C_MASK;
+	struct drbd_conf *mdev;
+	int vnr;
+
+	idr_for_each_entry(&tconn->volumes, mdev, vnr)
+		conn = min_t(enum drbd_conns, conn, mdev->state.conn);
+
+	return conn;
+}
+
 /**
  * cl_wide_st_chg() - true if the state change is a cluster wide one
  * @mdev:	DRBD device.

drivers/block/drbd/drbd_state.h

@@ -154,5 +154,6 @@ enum drbd_role conn_highest_role(struct drbd_tconn *tconn);
 enum drbd_role conn_highest_peer(struct drbd_tconn *tconn);
 enum drbd_disk_state conn_highest_disk(struct drbd_tconn *tconn);
 enum drbd_disk_state conn_highest_pdsk(struct drbd_tconn *tconn);
+enum drbd_conns conn_lowest_conn(struct drbd_tconn *tconn);
 
 #endif