net: bridge: vlan: add support for mcast querier global option

Add support to change and retrieve global vlan multicast querier state.
We just need to pass multicast context to br_multicast_set_querier
instead of bridge device and the rest of the logic remains the same.
Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/uapi/linux/if_bridge.h

@@ -560,6 +560,7 @@ enum {
 	BRIDGE_VLANDB_GOPTS_MCAST_QUERY_INTVL,
 	BRIDGE_VLANDB_GOPTS_MCAST_QUERY_RESPONSE_INTVL,
 	BRIDGE_VLANDB_GOPTS_MCAST_STARTUP_QUERY_INTVL,
+	BRIDGE_VLANDB_GOPTS_MCAST_QUERIER,
 	__BRIDGE_VLANDB_GOPTS_MAX
 };
 #define BRIDGE_VLANDB_GOPTS_MAX (__BRIDGE_VLANDB_GOPTS_MAX - 1)

net/bridge/br_multicast.c

@@ -4297,14 +4297,13 @@ bool br_multicast_router(const struct net_device *dev)
 }
 EXPORT_SYMBOL_GPL(br_multicast_router);
 
-int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
+int br_multicast_set_querier(struct net_bridge_mcast *brmctx, unsigned long val)
 {
-	struct net_bridge_mcast *brmctx = &br->multicast_ctx;
 	unsigned long max_delay;
 
 	val = !!val;
 
-	spin_lock_bh(&br->multicast_lock);
+	spin_lock_bh(&brmctx->br->multicast_lock);
 	if (brmctx->multicast_querier == val)
 		goto unlock;
 
@@ -4327,7 +4326,7 @@ int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
 #endif
 
 unlock:
-	spin_unlock_bh(&br->multicast_lock);
+	spin_unlock_bh(&brmctx->br->multicast_lock);
 
 	return 0;
 }

net/bridge/br_netlink.c

@@ -1309,7 +1309,8 @@ static int br_changelink(struct net_device *brdev, struct nlattr *tb[],
 	if (data[IFLA_BR_MCAST_QUERIER]) {
 		u8 mcast_querier = nla_get_u8(data[IFLA_BR_MCAST_QUERIER]);
 
-		err = br_multicast_set_querier(br, mcast_querier);
+		err = br_multicast_set_querier(&br->multicast_ctx,
+					       mcast_querier);
 		if (err)
 			return err;
 	}
@@ -1575,7 +1576,7 @@ static int br_fill_info(struct sk_buff *skb, const struct net_device *brdev)
 	    nla_put_u8(skb, IFLA_BR_MCAST_QUERY_USE_IFADDR,
 		       br_opt_get(br, BROPT_MULTICAST_QUERY_USE_IFADDR)) ||
 	    nla_put_u8(skb, IFLA_BR_MCAST_QUERIER,
-		       READ_ONCE(br->multicast_ctx.multicast_querier)) ||
+		       br->multicast_ctx.multicast_querier) ||
 	    nla_put_u8(skb, IFLA_BR_MCAST_STATS_ENABLED,
 		       br_opt_get(br, BROPT_MULTICAST_STATS_ENABLED)) ||
 	    nla_put_u32(skb, IFLA_BR_MCAST_HASH_ELASTICITY, RHT_ELASTICITY) ||

net/bridge/br_private.h

@@ -881,7 +881,7 @@ int br_multicast_set_router(struct net_bridge *br, unsigned long val);
 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val);
 int br_multicast_toggle(struct net_bridge *br, unsigned long val,
 			struct netlink_ext_ack *extack);
-int br_multicast_set_querier(struct net_bridge *br, unsigned long val);
+int br_multicast_set_querier(struct net_bridge_mcast *brmctx, unsigned long val);
 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val);
 int br_multicast_set_igmp_version(struct net_bridge_mcast *brmctx,
 				  unsigned long val);
@@ -1028,7 +1028,7 @@ __br_multicast_querier_exists(struct net_bridge_mcast *brmctx,
 {
 	bool own_querier_enabled;
 
-	if (READ_ONCE(brmctx->multicast_querier)) {
+	if (brmctx->multicast_querier) {
 		if (is_ipv6 && !br_opt_get(brmctx->br, BROPT_HAS_IPV6_ADDR))
 			own_querier_enabled = false;
 		else
@@ -1190,6 +1190,7 @@ br_multicast_ctx_options_equal(const struct net_bridge_mcast *brmctx1,
 	       brmctx2->multicast_query_response_interval &&
 	       brmctx1->multicast_startup_query_interval ==
 	       brmctx2->multicast_startup_query_interval &&
+	       brmctx1->multicast_querier == brmctx2->multicast_querier &&
 #if IS_ENABLED(CONFIG_IPV6)
 	       brmctx1->multicast_mld_version ==
 	       brmctx2->multicast_mld_version &&

net/bridge/br_sysfs_br.c

@@ -447,13 +447,13 @@ static ssize_t multicast_querier_show(struct device *d,
 				      char *buf)
 {
 	struct net_bridge *br = to_bridge(d);
-	return sprintf(buf, "%d\n", READ_ONCE(br->multicast_ctx.multicast_querier));
+	return sprintf(buf, "%d\n", br->multicast_ctx.multicast_querier);
 }
 
 static int set_multicast_querier(struct net_bridge *br, unsigned long val,
 				 struct netlink_ext_ack *extack)
 {
-	return br_multicast_set_querier(br, val);
+	return br_multicast_set_querier(&br->multicast_ctx, val);
 }
 
 static ssize_t multicast_querier_store(struct device *d,

net/bridge/br_vlan_options.c

@@ -294,7 +294,9 @@ bool br_vlan_global_opts_fill(struct sk_buff *skb, u16 vid, u16 vid_range,
 	    nla_put_u32(skb, BRIDGE_VLANDB_GOPTS_MCAST_LAST_MEMBER_CNT,
 			v_opts->br_mcast_ctx.multicast_last_member_count) ||
 	    nla_put_u32(skb, BRIDGE_VLANDB_GOPTS_MCAST_STARTUP_QUERY_CNT,
-			v_opts->br_mcast_ctx.multicast_startup_query_count))
+			v_opts->br_mcast_ctx.multicast_startup_query_count) ||
+	    nla_put_u8(skb, BRIDGE_VLANDB_GOPTS_MCAST_QUERIER,
+		       v_opts->br_mcast_ctx.multicast_querier))
 		goto out_err;
 
 	clockval = jiffies_to_clock_t(v_opts->br_mcast_ctx.multicast_last_member_interval);
@@ -355,6 +357,7 @@ static size_t rtnl_vlan_global_opts_nlmsg_size(void)
 		+ nla_total_size(sizeof(u64)) /* BRIDGE_VLANDB_GOPTS_MCAST_QUERY_INTVL */
 		+ nla_total_size(sizeof(u64)) /* BRIDGE_VLANDB_GOPTS_MCAST_QUERY_RESPONSE_INTVL */
 		+ nla_total_size(sizeof(u64)) /* BRIDGE_VLANDB_GOPTS_MCAST_STARTUP_QUERY_INTVL */
+		+ nla_total_size(sizeof(u8)) /* BRIDGE_VLANDB_GOPTS_MCAST_QUERIER */
 #endif
 		+ nla_total_size(sizeof(u16)); /* BRIDGE_VLANDB_GOPTS_RANGE */
 }
@@ -485,6 +488,15 @@ static int br_vlan_process_global_one_opts(const struct net_bridge *br,
 		v->br_mcast_ctx.multicast_startup_query_interval = clock_t_to_jiffies(val);
 		*changed = true;
 	}
+	if (tb[BRIDGE_VLANDB_GOPTS_MCAST_QUERIER]) {
+		u8 val;
+
+		val = nla_get_u8(tb[BRIDGE_VLANDB_GOPTS_MCAST_QUERIER]);
+		err = br_multicast_set_querier(&v->br_mcast_ctx, val);
+		if (err)
+			return err;
+		*changed = true;
+	}
 #if IS_ENABLED(CONFIG_IPV6)
 	if (tb[BRIDGE_VLANDB_GOPTS_MCAST_MLD_VERSION]) {
 		u8 ver;
@@ -507,6 +519,7 @@ static const struct nla_policy br_vlan_db_gpol[BRIDGE_VLANDB_GOPTS_MAX + 1] = {
 	[BRIDGE_VLANDB_GOPTS_MCAST_SNOOPING]	= { .type = NLA_U8 },
 	[BRIDGE_VLANDB_GOPTS_MCAST_MLD_VERSION]	= { .type = NLA_U8 },
 	[BRIDGE_VLANDB_GOPTS_MCAST_QUERY_INTVL]	= { .type = NLA_U64 },
+	[BRIDGE_VLANDB_GOPTS_MCAST_QUERIER]	= { .type = NLA_U8 },
 	[BRIDGE_VLANDB_GOPTS_MCAST_IGMP_VERSION]	= { .type = NLA_U8 },
 	[BRIDGE_VLANDB_GOPTS_MCAST_LAST_MEMBER_CNT]	= { .type = NLA_U32 },
 	[BRIDGE_VLANDB_GOPTS_MCAST_STARTUP_QUERY_CNT]	= { .type = NLA_U32 },