net: bridge: multicast: add vlan state initialization and control

Add helpers to enable/disable vlan multicast based on its flags, we need
two flags because we need to know if the vlan has multicast enabled
globally (user-controlled) and if it has it enabled on the specific device
(bridge or port). The new private vlan flags are:
 - BR_VLFLAG_MCAST_ENABLED: locally enabled multicast on the device, used
   when removing a vlan, toggling vlan mcast snooping and controlling
   single vlan (kernel-controlled, valid under RTNL and multicast_lock)
 - BR_VLFLAG_GLOBAL_MCAST_ENABLED: globally enabled multicast for the
   vlan, used to control the bridge-wide vlan mcast snooping for a
   single vlan (user-controlled, can be checked under any context)

Bridge vlan contexts are created with multicast snooping enabled by
default to be in line with the current bridge snooping defaults. In
order to actually activate per vlan snooping and context usage a
bridge-wide knob will be added later which will default to disabled.
If that knob is enabled then automatically all vlan snooping will be
enabled. All vlan contexts are initialized with the current bridge
multicast context defaults.

Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 110 insertions, 18 deletions

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 6f803f789217..ef4e7de3f18d 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -214,7 +214,7 @@ static void __fwd_add_star_excl(struct net_bridge_mcast_port *pmctx,
 	struct net_bridge_mcast *brmctx;
 
 	memset(&sg_key, 0, sizeof(sg_key));
-	brmctx = &pg->key.port->br->multicast_ctx;
+	brmctx = br_multicast_port_ctx_get_global(pmctx);
 	sg_key.port = pg->key.port;
 	sg_key.addr = *sg_ip;
 	if (br_sg_port_find(brmctx->br, &sg_key))
@@ -275,6 +275,7 @@ void br_multicast_star_g_handle_mode(struct net_bridge_port_group *pg,
 
 	memset(&sg_ip, 0, sizeof(sg_ip));
 	sg_ip = pg->key.addr;
+
 	for (pg_lst = mlock_dereference(mp->ports, br);
 	     pg_lst;
 	     pg_lst = mlock_dereference(pg_lst->next, br)) {
@@ -435,7 +436,7 @@ static void br_multicast_fwd_src_add(struct net_bridge_group_src *src)
 
 	memset(&sg_ip, 0, sizeof(sg_ip));
 	pmctx = &src->pg->key.port->multicast_ctx;
-	brmctx = &src->br->multicast_ctx;
+	brmctx = br_multicast_port_ctx_get_global(pmctx);
 	sg_ip = src->pg->key.addr;
 	sg_ip.src = src->addr.src;
 
@@ -1775,9 +1776,11 @@ static void br_multicast_enable(struct bridge_mcast_own_query *query)
 static void __br_multicast_enable_port_ctx(struct net_bridge_mcast_port *pmctx)
 {
 	struct net_bridge *br = pmctx->port->br;
-	struct net_bridge_mcast *brmctx = &pmctx->port->br->multicast_ctx;
+	struct net_bridge_mcast *brmctx;
 
-	if (!br_opt_get(br, BROPT_MULTICAST_ENABLED) || !netif_running(br->dev))
+	brmctx = br_multicast_port_ctx_get_global(pmctx);
+	if (!br_opt_get(br, BROPT_MULTICAST_ENABLED) ||
+	    !netif_running(br->dev))
 		return;
 
 	br_multicast_enable(&pmctx->ip4_own_query);
@@ -1799,18 +1802,17 @@ void br_multicast_enable_port(struct net_bridge_port *port)
 	spin_unlock(&br->multicast_lock);
 }
 
-void br_multicast_disable_port(struct net_bridge_port *port)
+static void __br_multicast_disable_port_ctx(struct net_bridge_mcast_port *pmctx)
 {
-	struct net_bridge_mcast_port *pmctx = &port->multicast_ctx;
-	struct net_bridge *br = port->br;
 	struct net_bridge_port_group *pg;
 	struct hlist_node *n;
 	bool del = false;
 
-	spin_lock(&br->multicast_lock);
-	hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
-		if (!(pg->flags & MDB_PG_FLAGS_PERMANENT))
-			br_multicast_find_del_pg(br, pg);
+	hlist_for_each_entry_safe(pg, n, &pmctx->port->mglist, mglist)
+		if (!(pg->flags & MDB_PG_FLAGS_PERMANENT) &&
+		    (!br_multicast_port_ctx_is_vlan(pmctx) ||
+		     pg->key.addr.vid == pmctx->vlan->vid))
+			br_multicast_find_del_pg(pmctx->port->br, pg);
 
 	del |= br_ip4_multicast_rport_del(pmctx);
 	del_timer(&pmctx->ip4_mc_router_timer);
@@ -1821,7 +1823,13 @@ void br_multicast_disable_port(struct net_bridge_port *port)
 	del_timer(&pmctx->ip6_own_query.timer);
 #endif
 	br_multicast_rport_del_notify(pmctx, del);
-	spin_unlock(&br->multicast_lock);
+}
+
+void br_multicast_disable_port(struct net_bridge_port *port)
+{
+	spin_lock(&port->br->multicast_lock);
+	__br_multicast_disable_port_ctx(&port->multicast_ctx);
+	spin_unlock(&port->br->multicast_lock);
 }
 
 static int __grp_src_delete_marked(struct net_bridge_port_group *pg)
@@ -3698,8 +3706,8 @@ void br_multicast_leave_snoopers(struct net_bridge *br)
 	br_ip6_multicast_leave_snoopers(br);
 }
 
-static void __br_multicast_open(struct net_bridge *br,
-				struct bridge_mcast_own_query *query)
+static void __br_multicast_open_query(struct net_bridge *br,
+				      struct bridge_mcast_own_query *query)
 {
 	query->startup_sent = 0;
 
@@ -3709,14 +3717,36 @@ static void __br_multicast_open(struct net_bridge *br,
 	mod_timer(&query->timer, jiffies);
 }
 
-void br_multicast_open(struct net_bridge *br)
+static void __br_multicast_open(struct net_bridge_mcast *brmctx)
 {
-	__br_multicast_open(br, &br->multicast_ctx.ip4_own_query);
+	__br_multicast_open_query(brmctx->br, &brmctx->ip4_own_query);
 #if IS_ENABLED(CONFIG_IPV6)
-	__br_multicast_open(br, &br->multicast_ctx.ip6_own_query);
+	__br_multicast_open_query(brmctx->br, &brmctx->ip6_own_query);
 #endif
 }
 
+void br_multicast_open(struct net_bridge *br)
+{
+	struct net_bridge_vlan_group *vg;
+	struct net_bridge_vlan *vlan;
+
+	ASSERT_RTNL();
+
+	vg = br_vlan_group(br);
+	if (vg) {
+		list_for_each_entry(vlan, &vg->vlan_list, vlist) {
+			struct net_bridge_mcast *brmctx;
+
+			brmctx = &vlan->br_mcast_ctx;
+			if (br_vlan_is_brentry(vlan) &&
+			    !br_multicast_ctx_vlan_disabled(brmctx))
+				__br_multicast_open(&vlan->br_mcast_ctx);
+		}
+	}
+
+	__br_multicast_open(&br->multicast_ctx);
+}
+
 static void __br_multicast_stop(struct net_bridge_mcast *brmctx)
 {
 	del_timer_sync(&brmctx->ip4_mc_router_timer);
@@ -3729,8 +3759,70 @@ static void __br_multicast_stop(struct net_bridge_mcast *brmctx)
 #endif
 }
 
+void br_multicast_toggle_one_vlan(struct net_bridge_vlan *vlan, bool on)
+{
+	struct net_bridge *br;
+
+	/* it's okay to check for the flag without the multicast lock because it
+	 * can only change under RTNL -> multicast_lock, we need the latter to
+	 * sync with timers and packets
+	 */
+	if (on == !!(vlan->priv_flags & BR_VLFLAG_MCAST_ENABLED))
+		return;
+
+	if (br_vlan_is_master(vlan)) {
+		br = vlan->br;
+
+		if (!br_vlan_is_brentry(vlan) ||
+		    (on &&
+		     br_multicast_ctx_vlan_global_disabled(&vlan->br_mcast_ctx)))
+			return;
+
+		spin_lock_bh(&br->multicast_lock);
+		vlan->priv_flags ^= BR_VLFLAG_MCAST_ENABLED;
+		spin_unlock_bh(&br->multicast_lock);
+
+		if (on)
+			__br_multicast_open(&vlan->br_mcast_ctx);
+		else
+			__br_multicast_stop(&vlan->br_mcast_ctx);
+	} else {
+		struct net_bridge_mcast *brmctx;
+
+		brmctx = br_multicast_port_ctx_get_global(&vlan->port_mcast_ctx);
+		if (on && br_multicast_ctx_vlan_global_disabled(brmctx))
+			return;
+
+		br = vlan->port->br;
+		spin_lock_bh(&br->multicast_lock);
+		vlan->priv_flags ^= BR_VLFLAG_MCAST_ENABLED;
+		if (on)
+			__br_multicast_enable_port_ctx(&vlan->port_mcast_ctx);
+		else
+			__br_multicast_disable_port_ctx(&vlan->port_mcast_ctx);
+		spin_unlock_bh(&br->multicast_lock);
+	}
+}
+
 void br_multicast_stop(struct net_bridge *br)
 {
+	struct net_bridge_vlan_group *vg;
+	struct net_bridge_vlan *vlan;
+
+	ASSERT_RTNL();
+
+	vg = br_vlan_group(br);
+	if (vg) {
+		list_for_each_entry(vlan, &vg->vlan_list, vlist) {
+			struct net_bridge_mcast *brmctx;
+
+			brmctx = &vlan->br_mcast_ctx;
+			if (br_vlan_is_brentry(vlan) &&
+			    !br_multicast_ctx_vlan_disabled(brmctx))
+				__br_multicast_stop(&vlan->br_mcast_ctx);
+		}
+	}
+
 	__br_multicast_stop(&br->multicast_ctx);
 }
 
@@ -3876,7 +3968,7 @@ static void br_multicast_start_querier(struct net_bridge_mcast *brmctx,
 {
 	struct net_bridge_port *port;
 
-	__br_multicast_open(brmctx->br, query);
+	__br_multicast_open_query(brmctx->br, query);
 
 	rcu_read_lock();
 	list_for_each_entry_rcu(port, &brmctx->br->port_list, list) {