bridge: netlink: add support for port's multicast_router attribute

Add IFLA_BRPORT_MULTICAST_ROUTER to allow setting/getting port's
multicast_router via netlink.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index 6468166..d78b442 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -138,6 +138,9 @@
 		+ nla_total_size(sizeof(u64))	/* IFLA_BRPORT_MESSAGE_AGE_TIMER */
 		+ nla_total_size(sizeof(u64))	/* IFLA_BRPORT_FORWARD_DELAY_TIMER */
 		+ nla_total_size(sizeof(u64))	/* IFLA_BRPORT_HOLD_TIMER */
+#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
+		+ nla_total_size(sizeof(u8))	/* IFLA_BRPORT_MULTICAST_ROUTER */
+#endif
 		+ 0;
 }
 
@@ -196,6 +199,12 @@
 	if (nla_put_u64(skb, IFLA_BRPORT_HOLD_TIMER, timerval))
 		return -EMSGSIZE;
 
+#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
+	if (nla_put_u8(skb, IFLA_BRPORT_MULTICAST_ROUTER,
+		       p->multicast_router))
+		return -EMSGSIZE;
+#endif
+
 	return 0;
 }
 
@@ -560,6 +569,7 @@
 	[IFLA_BRPORT_UNICAST_FLOOD] = { .type = NLA_U8 },
 	[IFLA_BRPORT_PROXYARP]	= { .type = NLA_U8 },
 	[IFLA_BRPORT_PROXYARP_WIFI] = { .type = NLA_U8 },
+	[IFLA_BRPORT_MULTICAST_ROUTER] = { .type = NLA_U8 },
 };
 
 /* Change the state of the port and notify spanning tree */
@@ -634,6 +644,15 @@
 	if (tb[IFLA_BRPORT_FLUSH])
 		br_fdb_delete_by_port(p->br, p, 0, 0);
 
+#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
+	if (tb[IFLA_BRPORT_MULTICAST_ROUTER]) {
+		u8 mcast_router = nla_get_u8(tb[IFLA_BRPORT_MULTICAST_ROUTER]);
+
+		err = br_multicast_set_port_router(p, mcast_router);
+		if (err)
+			return err;
+	}
+#endif
 	br_port_flags_change(p, old_flags ^ p->flags);
 	return 0;
 }