Merge tag 'locks-v3.17-2' of git://git.samba.org/jlayton/linux

[karo-tx-linux.git] / net / bridge / br_multicast.c

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index abfa0b65a1118eb0abae4dd69f78e7285537acd8..7751c92c8c57fc24b0c18e4d20a095bfa02e9ff0 100644 (file)
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -1174,7 +1174,7 @@ static void br_multicast_add_router(struct net_bridge *br,
        }
 
        if (slot)
-               hlist_add_after_rcu(slot, &port->rlist);
+               hlist_add_behind_rcu(&port->rlist, slot);
        else
                hlist_add_head_rcu(&port->rlist, &br->router_list);
 }
@@ -2215,6 +2215,43 @@ unlock:
 }
 EXPORT_SYMBOL_GPL(br_multicast_list_adjacent);
 
+/**
+ * br_multicast_has_querier_anywhere - Checks for a querier on a bridge
+ * @dev: The bridge port providing the bridge on which to check for a querier
+ * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
+ *
+ * Checks whether the given interface has a bridge on top and if so returns
+ * true if a valid querier exists anywhere on the bridged link layer.
+ * Otherwise returns false.
+ */
+bool br_multicast_has_querier_anywhere(struct net_device *dev, int proto)
+{
+       struct net_bridge *br;
+       struct net_bridge_port *port;
+       struct ethhdr eth;
+       bool ret = false;
+
+       rcu_read_lock();
+       if (!br_port_exists(dev))
+               goto unlock;
+
+       port = br_port_get_rcu(dev);
+       if (!port || !port->br)
+               goto unlock;
+
+       br = port->br;
+
+       memset(&eth, 0, sizeof(eth));
+       eth.h_proto = htons(proto);
+
+       ret = br_multicast_querier_exists(br, &eth);
+
+unlock:
+       rcu_read_unlock();
+       return ret;
+}
+EXPORT_SYMBOL_GPL(br_multicast_has_querier_anywhere);
+
 /**
  * br_multicast_has_querier_adjacent - Checks for a querier behind a bridge port
  * @dev: The bridge port adjacent to which to check for a querier