bridge: Encapsulate data path neighbor suppression logic

Currently, there are various places in the bridge data path that check
whether neighbor suppression is enabled on a given bridge port.

As a preparation for per-{Port, VLAN} neighbor suppression, encapsulate
this logic in a function and pass the VLAN ID of the packet as an
argument.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/bridge/br_arp_nd_proxy.c

@@ -158,7 +158,7 @@ void br_do_proxy_suppress_arp(struct sk_buff *skb, struct net_bridge *br,
 		return;
 
 	if (br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED)) {
-		if (p && (p->flags & BR_NEIGH_SUPPRESS))
+		if (br_is_neigh_suppress_enabled(p, vid))
 			return;
 		if (parp->ar_op != htons(ARPOP_RREQUEST) &&
 		    parp->ar_op != htons(ARPOP_RREPLY) &&
@@ -202,8 +202,8 @@ void br_do_proxy_suppress_arp(struct sk_buff *skb, struct net_bridge *br,
 			bool replied = false;
 
 			if ((p && (p->flags & BR_PROXYARP)) ||
-			    (f->dst && (f->dst->flags & (BR_PROXYARP_WIFI |
-							 BR_NEIGH_SUPPRESS)))) {
+			    (f->dst && (f->dst->flags & BR_PROXYARP_WIFI)) ||
+			    br_is_neigh_suppress_enabled(f->dst, vid)) {
 				if (!vid)
 					br_arp_send(br, p, skb->dev, sip, tip,
 						    sha, n->ha, sha, 0, 0);
@@ -407,7 +407,7 @@ void br_do_suppress_nd(struct sk_buff *skb, struct net_bridge *br,
 
 	BR_INPUT_SKB_CB(skb)->proxyarp_replied = 0;
 
-	if (p && (p->flags & BR_NEIGH_SUPPRESS))
+	if (br_is_neigh_suppress_enabled(p, vid))
 		return;
 
 	if (msg->icmph.icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT &&
@@ -461,7 +461,7 @@ void br_do_suppress_nd(struct sk_buff *skb, struct net_bridge *br,
 		if (f) {
 			bool replied = false;
 
-			if (f->dst && (f->dst->flags & BR_NEIGH_SUPPRESS)) {
+			if (br_is_neigh_suppress_enabled(f->dst, vid)) {
 				if (vid != 0)
 					br_nd_send(br, p, skb, n,
 						   skb->vlan_proto,
@@ -483,3 +483,8 @@ void br_do_suppress_nd(struct sk_buff *skb, struct net_bridge *br,
 	}
 }
 #endif
+
+bool br_is_neigh_suppress_enabled(const struct net_bridge_port *p, u16 vid)
+{
+	return p && (p->flags & BR_NEIGH_SUPPRESS);
+}

net/bridge/br_forward.c

@@ -226,7 +226,8 @@ void br_flood(struct net_bridge *br, struct sk_buff *skb,
 		if (p->flags & BR_PROXYARP)
 			continue;
 		if (BR_INPUT_SKB_CB(skb)->proxyarp_replied &&
-		    (p->flags & (BR_PROXYARP_WIFI | BR_NEIGH_SUPPRESS)))
+		    ((p->flags & BR_PROXYARP_WIFI) ||
+		     br_is_neigh_suppress_enabled(p, vid)))
 			continue;
 
 		prev = maybe_deliver(prev, p, skb, local_orig);

net/bridge/br_private.h

@@ -2220,4 +2220,5 @@ void br_do_proxy_suppress_arp(struct sk_buff *skb, struct net_bridge *br,
 void br_do_suppress_nd(struct sk_buff *skb, struct net_bridge *br,
 		       u16 vid, struct net_bridge_port *p, struct nd_msg *msg);
 struct nd_msg *br_is_nd_neigh_msg(struct sk_buff *skb, struct nd_msg *m);
+bool br_is_neigh_suppress_enabled(const struct net_bridge_port *p, u16 vid);
 #endif