mac80211: improve cleanup when leaving mesh

It is not necessary to stop the mesh beacon in the mac80211 ndo_stop
handler, since cfg80211 has already left the mesh on NETDEV_GOING_DOWN
notification.

Also some improvements to ieee80211_stop_mesh():

 - flush mpath entries.
 - flush sta entries per-sdata so we don't remove entries belonging to
   other vifs on the same hw.
Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/iface.c

@@ -777,14 +777,6 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata,
 		synchronize_rcu();
 		skb_queue_purge(&sdata->skb_queue);
 
-		/*
-		 * Disable beaconing here for mesh only, AP and IBSS
-		 * are already taken care of.
-		 */
-		if (sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
-			ieee80211_bss_info_change_notify(sdata,
-				BSS_CHANGED_BEACON_ENABLED);
-
 		/*
 		 * Free all remaining keys, there shouldn't be any,
 		 * except maybe group keys in AP more or WDS?

net/mac80211/mesh.c

@@ -621,9 +621,13 @@ void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
 
 	netif_carrier_off(sdata->dev);
 
+	/* stop the beacon */
 	ifmsh->mesh_id_len = 0;
 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
-	sta_info_flush(local, NULL);
+
+	/* flush STAs and mpaths on this iface */
+	sta_info_flush(sdata->local, sdata);
+	mesh_path_flush_by_iface(sdata);
 
 	del_timer_sync(&sdata->u.mesh.housekeeping_timer);
 	del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);