net: bridge: add per-port multicast flood flag

Add a per-port flag to control the unknown multicast flood, similar to the
unknown unicast flood flag and break a few long lines in the netlink flag
exports.
Signed-off-by: NNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/linux/if_bridge.h

@@ -45,6 +45,7 @@ struct br_ip_list {
 #define BR_PROXYARP		BIT(8)
 #define BR_LEARNING_SYNC	BIT(9)
 #define BR_PROXYARP_WIFI	BIT(10)
+#define BR_MCAST_FLOOD		BIT(11)
 
 #define BR_DEFAULT_AGEING_TIME	(300 * HZ)
 

include/uapi/linux/if_link.h

@@ -318,6 +318,7 @@ enum {
 	IFLA_BRPORT_FLUSH,
 	IFLA_BRPORT_MULTICAST_ROUTER,
 	IFLA_BRPORT_PAD,
+	IFLA_BRPORT_MCAST_FLOOD,
 	__IFLA_BRPORT_MAX
 };
 #define IFLA_BRPORT_MAX (__IFLA_BRPORT_MAX - 1)

net/bridge/br_forward.c

@@ -186,6 +186,9 @@ void br_flood(struct net_bridge *br, struct sk_buff *skb,
 		/* Do not flood unicast traffic to ports that turn it off */
 		if (pkt_type == BR_PKT_UNICAST && !(p->flags & BR_FLOOD))
 			continue;
+		if (pkt_type == BR_PKT_MULTICAST &&
+		    !(p->flags & BR_MCAST_FLOOD))
+			continue;
 
 		/* Do not flood to ports that enable proxy ARP */
 		if (p->flags & BR_PROXYARP)

net/bridge/br_if.c

@@ -362,7 +362,7 @@ static struct net_bridge_port *new_nbp(struct net_bridge *br,
 	p->path_cost = port_cost(dev);
 	p->priority = 0x8000 >> BR_PORT_BITS;
 	p->port_no = index;
-	p->flags = BR_LEARNING | BR_FLOOD;
+	p->flags = BR_LEARNING | BR_FLOOD | BR_MCAST_FLOOD;
 	br_init_port(p);
 	br_set_state(p, BR_STATE_DISABLED);
 	br_stp_port_timer_init(p);

net/bridge/br_netlink.c

@@ -169,10 +169,15 @@ static int br_port_fill_attrs(struct sk_buff *skb,
 	    nla_put_u32(skb, IFLA_BRPORT_COST, p->path_cost) ||
 	    nla_put_u8(skb, IFLA_BRPORT_MODE, mode) ||
 	    nla_put_u8(skb, IFLA_BRPORT_GUARD, !!(p->flags & BR_BPDU_GUARD)) ||
-	    nla_put_u8(skb, IFLA_BRPORT_PROTECT, !!(p->flags & BR_ROOT_BLOCK)) ||
-	    nla_put_u8(skb, IFLA_BRPORT_FAST_LEAVE, !!(p->flags & BR_MULTICAST_FAST_LEAVE)) ||
+	    nla_put_u8(skb, IFLA_BRPORT_PROTECT,
+		       !!(p->flags & BR_ROOT_BLOCK)) ||
+	    nla_put_u8(skb, IFLA_BRPORT_FAST_LEAVE,
+		       !!(p->flags & BR_MULTICAST_FAST_LEAVE)) ||
 	    nla_put_u8(skb, IFLA_BRPORT_LEARNING, !!(p->flags & BR_LEARNING)) ||
-	    nla_put_u8(skb, IFLA_BRPORT_UNICAST_FLOOD, !!(p->flags & BR_FLOOD)) ||
+	    nla_put_u8(skb, IFLA_BRPORT_UNICAST_FLOOD,
+		       !!(p->flags & BR_FLOOD)) ||
+	    nla_put_u8(skb, IFLA_BRPORT_MCAST_FLOOD,
+		       !!(p->flags & BR_MCAST_FLOOD)) ||
 	    nla_put_u8(skb, IFLA_BRPORT_PROXYARP, !!(p->flags & BR_PROXYARP)) ||
 	    nla_put_u8(skb, IFLA_BRPORT_PROXYARP_WIFI,
 		       !!(p->flags & BR_PROXYARP_WIFI)) ||
@@ -630,6 +635,7 @@ static int br_setport(struct net_bridge_port *p, struct nlattr *tb[])
 	br_set_port_flag(p, tb, IFLA_BRPORT_PROTECT, BR_ROOT_BLOCK);
 	br_set_port_flag(p, tb, IFLA_BRPORT_LEARNING, BR_LEARNING);
 	br_set_port_flag(p, tb, IFLA_BRPORT_UNICAST_FLOOD, BR_FLOOD);
+	br_set_port_flag(p, tb, IFLA_BRPORT_MCAST_FLOOD, BR_MCAST_FLOOD);
 	br_set_port_flag(p, tb, IFLA_BRPORT_PROXYARP, BR_PROXYARP);
 	br_set_port_flag(p, tb, IFLA_BRPORT_PROXYARP_WIFI, BR_PROXYARP_WIFI);
 

net/bridge/br_sysfs_if.c

@@ -171,6 +171,7 @@ BRPORT_ATTR_FLAG(learning, BR_LEARNING);
 BRPORT_ATTR_FLAG(unicast_flood, BR_FLOOD);
 BRPORT_ATTR_FLAG(proxyarp, BR_PROXYARP);
 BRPORT_ATTR_FLAG(proxyarp_wifi, BR_PROXYARP_WIFI);
+BRPORT_ATTR_FLAG(multicast_flood, BR_MCAST_FLOOD);
 
 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)