From 07f8ac4a1e26e8283542cdaf658a6e2a12fd6980 Mon Sep 17 00:00:00 2001 From: Linus Lüssing Date: Sat, 7 Jun 2014 18:26:28 +0200 Subject: bridge: add export of multicast database adjacent to net_dev MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit With this new, exported function br_multicast_list_adjacent(net_dev) a list of IPv4/6 addresses is returned. This list contains all multicast addresses sensed by the bridge multicast snooping feature on all bridge ports of the bridge interface of net_dev, excluding addresses from the specified net_device itself. Adding bridge support to the batman-adv multicast optimization requires batman-adv knowing about the existence of bridged-in multicast listeners to be able to reliably serve them with multicast packets. Signed-off-by: Linus Lüssing Signed-off-by: David S. Miller --- net/bridge/br_multicast.c | 58 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) (limited to 'net/bridge/br_multicast.c') diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index b3f17c9b4d06..772476b7c4b7 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -11,6 +11,7 @@ */ #include +#include #include #include #include @@ -2141,3 +2142,60 @@ unlock: return err; } + +/** + * br_multicast_list_adjacent - Returns snooped multicast addresses + * @dev: The bridge port adjacent to which to retrieve addresses + * @br_ip_list: The list to store found, snooped multicast IP addresses in + * + * Creates a list of IP addresses (struct br_ip_list) sensed by the multicast + * snooping feature on all bridge ports of dev's bridge device, excluding + * the addresses from dev itself. + * + * Returns the number of items added to br_ip_list. + * + * Notes: + * - br_ip_list needs to be initialized by caller + * - br_ip_list might contain duplicates in the end + * (needs to be taken care of by caller) + * - br_ip_list needs to be freed by caller + */ +int br_multicast_list_adjacent(struct net_device *dev, + struct list_head *br_ip_list) +{ + struct net_bridge *br; + struct net_bridge_port *port; + struct net_bridge_port_group *group; + struct br_ip_list *entry; + int count = 0; + + rcu_read_lock(); + if (!br_ip_list || !br_port_exists(dev)) + goto unlock; + + port = br_port_get_rcu(dev); + if (!port || !port->br) + goto unlock; + + br = port->br; + + list_for_each_entry_rcu(port, &br->port_list, list) { + if (!port->dev || port->dev == dev) + continue; + + hlist_for_each_entry_rcu(group, &port->mglist, mglist) { + entry = kmalloc(sizeof(*entry), GFP_ATOMIC); + if (!entry) + goto unlock; + + entry->addr = group->addr; + list_add(&entry->list, br_ip_list); + count++; + } + } + +unlock: + rcu_read_unlock(); + return count; +} +EXPORT_SYMBOL_GPL(br_multicast_list_adjacent); -- cgit v1.2.3-59-g8ed1b