Adding bridge support to the batman-adv multicast optimization requires batman-adv knowing about the existence of bridged-in IGMP/MLD queriers to be able to reliably serve any multicast listener behind this same bridge.
Signed-off-by: Linus Lüssing linus.luessing@web.de --- include/linux/if_bridge.h | 1 + net/bridge/br_multicast.c | 72 +++++++++++++++++++++++++++++++++++++++++---- net/bridge/br_private.h | 1 + 3 files changed, 68 insertions(+), 6 deletions(-)
diff --git a/include/linux/if_bridge.h b/include/linux/if_bridge.h index 44d6eb0..fd22789 100644 --- a/include/linux/if_bridge.h +++ b/include/linux/if_bridge.h @@ -38,5 +38,6 @@ typedef int br_should_route_hook_t(struct sk_buff *skb); extern br_should_route_hook_t __rcu *br_should_route_hook; int br_multicast_list_adjacent(struct net_device *dev, struct list_head *br_ip_list); +bool br_multicast_has_querier_adjacent(struct net_device *dev, int proto);
#endif diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 772476b..cd3cf39 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -1081,6 +1081,7 @@ static int br_ip6_multicast_mld2_report(struct net_bridge *br, #endif
static bool br_ip4_multicast_select_querier(struct net_bridge *br, + struct net_bridge_port *port, __be32 saddr) { if (!timer_pending(&br->ip4_own_query.timer) && @@ -1098,11 +1099,15 @@ static bool br_ip4_multicast_select_querier(struct net_bridge *br, update: br->ip4_querier.addr.u.ip4 = saddr;
+ /* update protected by general multicast_lock by caller */ + rcu_assign_pointer(br->ip4_querier.port, port); + return true; }
#if IS_ENABLED(CONFIG_IPV6) static bool br_ip6_multicast_select_querier(struct net_bridge *br, + struct net_bridge_port *port, struct in6_addr *saddr) { if (!timer_pending(&br->ip6_own_query.timer) && @@ -1117,19 +1122,23 @@ static bool br_ip6_multicast_select_querier(struct net_bridge *br, update: br->ip6_querier.addr.u.ip6 = *saddr;
+ /* update protected by general multicast_lock by caller */ + rcu_assign_pointer(br->ip6_querier.port, port); + return true; } #endif
static bool br_multicast_select_querier(struct net_bridge *br, + struct net_bridge_port *port, struct br_ip *saddr) { switch (saddr->proto) { case htons(ETH_P_IP): - return br_ip4_multicast_select_querier(br, saddr->u.ip4); + return br_ip4_multicast_select_querier(br, port, saddr->u.ip4); #if IS_ENABLED(CONFIG_IPV6) case htons(ETH_P_IPV6): - return br_ip6_multicast_select_querier(br, &saddr->u.ip6); + return br_ip6_multicast_select_querier(br, port, &saddr->u.ip6); #endif }
@@ -1201,7 +1210,7 @@ static void br_multicast_query_received(struct net_bridge *br, struct br_ip *saddr, unsigned long max_delay) { - if (!br_multicast_select_querier(br, saddr)) + if (!br_multicast_select_querier(br, port, saddr)) return;
br_multicast_update_query_timer(br, query, max_delay); @@ -1804,12 +1813,14 @@ int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port, }
static void br_multicast_query_expired(struct net_bridge *br, - struct bridge_mcast_own_query *query) + struct bridge_mcast_own_query *query, + struct bridge_mcast_querier *querier) { spin_lock(&br->multicast_lock); if (query->startup_sent < br->multicast_startup_query_count) query->startup_sent++;
+ rcu_assign_pointer(querier, NULL); br_multicast_send_query(br, NULL, query); spin_unlock(&br->multicast_lock); } @@ -1818,7 +1829,7 @@ static void br_ip4_multicast_query_expired(unsigned long data) { struct net_bridge *br = (void *)data;
- br_multicast_query_expired(br, &br->ip4_own_query); + br_multicast_query_expired(br, &br->ip4_own_query, &br->ip4_querier); }
#if IS_ENABLED(CONFIG_IPV6) @@ -1826,7 +1837,7 @@ static void br_ip6_multicast_query_expired(unsigned long data) { struct net_bridge *br = (void *)data;
- br_multicast_query_expired(br, &br->ip6_own_query); + br_multicast_query_expired(br, &br->ip6_own_query, &br->ip6_querier); } #endif
@@ -1849,8 +1860,10 @@ void br_multicast_init(struct net_bridge *br) br->multicast_membership_interval = 260 * HZ;
br->ip4_other_query.delay_time = 0; + br->ip4_querier.port = NULL; #if IS_ENABLED(CONFIG_IPV6) br->ip6_other_query.delay_time = 0; + br->ip6_querier.port = NULL; #endif
spin_lock_init(&br->multicast_lock); @@ -2199,3 +2212,50 @@ unlock: return count; } EXPORT_SYMBOL_GPL(br_multicast_list_adjacent); + +/** + * 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 + * @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 selected querier is behind one of the other ports of this + * bridge. Otherwise returns false. + */ +bool br_multicast_has_querier_adjacent(struct net_device *dev, int proto) +{ + struct net_bridge *br; + struct net_bridge_port *port; + 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; + + switch (proto) { + case ETH_P_IP: + if (!timer_pending(&br->ip4_other_query.timer) || + rcu_dereference(br->ip4_querier.port) == port) + goto unlock; + break; + case ETH_P_IPV6: + if (!timer_pending(&br->ip6_other_query.timer) || + rcu_dereference(br->ip6_querier.port) == port) + goto unlock; + break; + default: + goto unlock; + } + + ret = true; +unlock: + rcu_read_unlock(); + return ret; +} +EXPORT_SYMBOL_GPL(br_multicast_has_querier_adjacent); diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 50e2ab0..8346e95 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -70,6 +70,7 @@ struct bridge_mcast_other_query { /* selected querier */ struct bridge_mcast_querier { struct br_ip addr; + struct net_bridge_port __rcu *port; }; #endif