net: bridge: mcast: add support for group query retransmit

We need to be able to retransmit group-specific and group-and-source
specific queries. The new timer takes care of those.

v3: add IPv6 support

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index cfb9533..ab3ab75 100644 (file)
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -50,6 +50,7 @@ static void br_ip4_multicast_leave_group(struct net_bridge *br,
                                         __be32 group,
                                         __u16 vid,
                                         const unsigned char *src);
+static void br_multicast_port_group_rexmit(struct timer_list *t);
 
 static void __del_port_router(struct net_bridge_port *p);
 #if IS_ENABLED(CONFIG_IPV6)
@@ -184,6 +185,7 @@ void br_multicast_del_pg(struct net_bridge_mdb_entry *mp,
        rcu_assign_pointer(*pp, pg->next);
        hlist_del_init(&pg->mglist);
        del_timer(&pg->timer);
+       del_timer(&pg->rexmit_timer);
        hlist_for_each_entry_safe(ent, tmp, &pg->src_list, node)
                br_multicast_del_group_src(ent);
        br_mdb_notify(br->dev, pg->port, &pg->addr, RTM_DELMDB, pg->flags);
@@ -237,7 +239,8 @@ static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
                                                    struct net_bridge_port_group *pg,
                                                    __be32 ip_dst, __be32 group,
                                                    bool with_srcs, bool over_lmqt,
-                                                   u8 sflag, u8 *igmp_type)
+                                                   u8 sflag, u8 *igmp_type,
+                                                   bool *need_rexmit)
 {
        struct net_bridge_port *p = pg ? pg->port : NULL;
        struct net_bridge_group_src *ent;
@@ -352,6 +355,8 @@ static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
                            ent->src_query_rexmit_cnt > 0) {
                                ihv3->srcs[lmqt_srcs++] = ent->addr.u.ip4;
                                ent->src_query_rexmit_cnt--;
+                               if (need_rexmit && ent->src_query_rexmit_cnt)
+                                       *need_rexmit = true;
                        }
                }
                if (WARN_ON(lmqt_srcs != ntohs(ihv3->nsrcs))) {
@@ -380,7 +385,8 @@ static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
                                                    const struct in6_addr *ip6_dst,
                                                    const struct in6_addr *group,
                                                    bool with_srcs, bool over_llqt,
-                                                   u8 sflag, u8 *igmp_type)
+                                                   u8 sflag, u8 *igmp_type,
+                                                   bool *need_rexmit)
 {
        struct net_bridge_port *p = pg ? pg->port : NULL;
        struct net_bridge_group_src *ent;
@@ -510,6 +516,8 @@ static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
                            ent->src_query_rexmit_cnt > 0) {
                                mld2q->mld2q_srcs[llqt_srcs++] = ent->addr.u.ip6;
                                ent->src_query_rexmit_cnt--;
+                               if (need_rexmit && ent->src_query_rexmit_cnt)
+                                       *need_rexmit = true;
                        }
                }
                if (WARN_ON(llqt_srcs != ntohs(mld2q->mld2q_nsrcs))) {
@@ -540,7 +548,8 @@ static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
                                                struct br_ip *ip_dst,
                                                struct br_ip *group,
                                                bool with_srcs, bool over_lmqt,
-                                               u8 sflag, u8 *igmp_type)
+                                               u8 sflag, u8 *igmp_type,
+                                               bool *need_rexmit)
 {
        __be32 ip4_dst;
 
@@ -550,7 +559,8 @@ static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
                return br_ip4_multicast_alloc_query(br, pg,
                                                    ip4_dst, group->u.ip4,
                                                    with_srcs, over_lmqt,
-                                                   sflag, igmp_type);
+                                                   sflag, igmp_type,
+                                                   need_rexmit);
 #if IS_ENABLED(CONFIG_IPV6)
        case htons(ETH_P_IPV6): {
                struct in6_addr ip6_dst;
@@ -564,7 +574,8 @@ static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
                return br_ip6_multicast_alloc_query(br, pg,
                                                    &ip6_dst, &group->u.ip6,
                                                    with_srcs, over_lmqt,
-                                                   sflag, igmp_type);
+                                                   sflag, igmp_type,
+                                                   need_rexmit);
        }
 #endif
        }
@@ -708,8 +719,9 @@ struct net_bridge_port_group *br_multicast_new_port_group(
        p->filter_mode = filter_mode;
        INIT_HLIST_HEAD(&p->src_list);
        rcu_assign_pointer(p->next, next);
-       hlist_add_head(&p->mglist, &port->mglist);
        timer_setup(&p->timer, br_multicast_port_group_expired, 0);
+       timer_setup(&p->rexmit_timer, br_multicast_port_group_rexmit, 0);
+       hlist_add_head(&p->mglist, &port->mglist);
 
        if (src)
                memcpy(p->eth_addr, src, ETH_ALEN);
@@ -943,7 +955,8 @@ static void __br_multicast_send_query(struct net_bridge *br,
                                      struct br_ip *ip_dst,
                                      struct br_ip *group,
                                      bool with_srcs,
-                                     u8 sflag)
+                                     u8 sflag,
+                                     bool *need_rexmit)
 {
        bool over_lmqt = !!sflag;
        struct sk_buff *skb;
@@ -951,7 +964,8 @@ static void __br_multicast_send_query(struct net_bridge *br,
 
 again_under_lmqt:
        skb = br_multicast_alloc_query(br, pg, ip_dst, group, with_srcs,
-                                      over_lmqt, sflag, &igmp_type);
+                                      over_lmqt, sflag, &igmp_type,
+                                      need_rexmit);
        if (!skb)
                return;
 
@@ -1004,7 +1018,8 @@ static void br_multicast_send_query(struct net_bridge *br,
        if (!other_query || timer_pending(&other_query->timer))
                return;
 
-       __br_multicast_send_query(br, port, NULL, NULL, &br_group, false, 0);
+       __br_multicast_send_query(br, port, NULL, NULL, &br_group, false, 0,
+                                 NULL);
 
        time = jiffies;
        time += own_query->startup_sent < br->multicast_startup_query_count ?
@@ -1049,6 +1064,44 @@ static void br_ip6_multicast_port_query_expired(struct timer_list *t)
 }
 #endif
 
+static void br_multicast_port_group_rexmit(struct timer_list *t)
+{
+       struct net_bridge_port_group *pg = from_timer(pg, t, rexmit_timer);
+       struct bridge_mcast_other_query *other_query = NULL;
+       struct net_bridge *br = pg->port->br;
+       bool need_rexmit = false;
+
+       spin_lock(&br->multicast_lock);
+       if (!netif_running(br->dev) || hlist_unhashed(&pg->mglist) ||
+           !br_opt_get(br, BROPT_MULTICAST_ENABLED) ||
+           !br_opt_get(br, BROPT_MULTICAST_QUERIER))
+               goto out;
+
+       if (pg->addr.proto == htons(ETH_P_IP))
+               other_query = &br->ip4_other_query;
+#if IS_ENABLED(CONFIG_IPV6)
+       else
+               other_query = &br->ip6_other_query;
+#endif
+
+       if (!other_query || timer_pending(&other_query->timer))
+               goto out;
+
+       if (pg->grp_query_rexmit_cnt) {
+               pg->grp_query_rexmit_cnt--;
+               __br_multicast_send_query(br, pg->port, pg, &pg->addr,
+                                         &pg->addr, false, 1, NULL);
+       }
+       __br_multicast_send_query(br, pg->port, pg, &pg->addr,
+                                 &pg->addr, true, 0, &need_rexmit);
+
+       if (pg->grp_query_rexmit_cnt || need_rexmit)
+               mod_timer(&pg->rexmit_timer, jiffies +
+                                            br->multicast_last_member_interval);
+out:
+       spin_unlock(&br->multicast_lock);
+}
+
 static void br_mc_disabled_update(struct net_device *dev, bool value)
 {
        struct switchdev_attr attr = {
@@ -1658,7 +1711,7 @@ br_multicast_leave_group(struct net_bridge *br,
 
        if (br_opt_get(br, BROPT_MULTICAST_QUERIER)) {
                __br_multicast_send_query(br, port, NULL, NULL, &mp->addr,
-                                         false, 0);
+                                         false, 0, NULL);
 
                time = jiffies + br->multicast_last_member_count *
                                 br->multicast_last_member_interval;

diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index e063272..da8df27 100644 (file)
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -240,10 +240,12 @@ struct net_bridge_port_group {
        unsigned char                   eth_addr[ETH_ALEN] __aligned(2);
        unsigned char                   flags;
        unsigned char                   filter_mode;
+       unsigned char                   grp_query_rexmit_cnt;
 
        struct hlist_head               src_list;
        unsigned int                    src_ents;
        struct timer_list               timer;
+       struct timer_list               rexmit_timer;
        struct hlist_node               mglist;
 
        struct rcu_head                 rcu;
@@ -868,6 +870,12 @@ static inline int br_multicast_igmp_type(const struct sk_buff *skb)
 {
        return BR_INPUT_SKB_CB(skb)->igmp;
 }
+
+static inline unsigned long br_multicast_lmqt(const struct net_bridge *br)
+{
+       return br->multicast_last_member_interval *
+              br->multicast_last_member_count;
+}
 #else
 static inline int br_multicast_rcv(struct net_bridge *br,
                                   struct net_bridge_port *port,