bridge: netlink: add support for default_pvid

Add IFLA_BR_VLAN_DEFAULT_PVID to allow setting/getting bridge's
default_pvid via netlink.

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

include/uapi/linux/if_link.h

@@ -262,6 +262,7 @@ enum {
 	IFLA_BR_NF_CALL_IPTABLES,
 	IFLA_BR_NF_CALL_IP6TABLES,
 	IFLA_BR_NF_CALL_ARPTABLES,
+	IFLA_BR_VLAN_DEFAULT_PVID,
 	__IFLA_BR_MAX,
 };
 

net/bridge/br_netlink.c

@@ -784,6 +784,7 @@ static const struct nla_policy br_policy[IFLA_BR_MAX + 1] = {
 	[IFLA_BR_NF_CALL_IPTABLES] = { .type = NLA_U8 },
 	[IFLA_BR_NF_CALL_IP6TABLES] = { .type = NLA_U8 },
 	[IFLA_BR_NF_CALL_ARPTABLES] = { .type = NLA_U8 },
+	[IFLA_BR_VLAN_DEFAULT_PVID] = { .type = NLA_U16 },
 };
 
 static int br_changelink(struct net_device *brdev, struct nlattr *tb[],
@@ -847,6 +848,14 @@ static int br_changelink(struct net_device *brdev, struct nlattr *tb[],
 		if (err)
 			return err;
 	}
+
+	if (data[IFLA_BR_VLAN_DEFAULT_PVID]) {
+		__u16 defpvid = nla_get_u16(data[IFLA_BR_VLAN_DEFAULT_PVID]);
+
+		err = __br_vlan_set_default_pvid(br, defpvid);
+		if (err)
+			return err;
+	}
 #endif
 
 	if (data[IFLA_BR_GROUP_FWD_MASK]) {
@@ -1007,6 +1016,7 @@ static size_t br_get_size(const struct net_device *brdev)
 	       nla_total_size(sizeof(u8)) +     /* IFLA_BR_VLAN_FILTERING */
 #ifdef CONFIG_BRIDGE_VLAN_FILTERING
 	       nla_total_size(sizeof(__be16)) +	/* IFLA_BR_VLAN_PROTOCOL */
+	       nla_total_size(sizeof(u16)) +    /* IFLA_BR_VLAN_DEFAULT_PVID */
 #endif
 	       nla_total_size(sizeof(u16)) +    /* IFLA_BR_GROUP_FWD_MASK */
 	       nla_total_size(sizeof(struct ifla_bridge_id)) +   /* IFLA_BR_ROOT_ID */
@@ -1094,7 +1104,8 @@ static int br_fill_info(struct sk_buff *skb, const struct net_device *brdev)
 		return -EMSGSIZE;
 
 #ifdef CONFIG_BRIDGE_VLAN_FILTERING
-	if (nla_put_be16(skb, IFLA_BR_VLAN_PROTOCOL, br->vlan_proto))
+	if (nla_put_be16(skb, IFLA_BR_VLAN_PROTOCOL, br->vlan_proto) ||
+	    nla_put_u16(skb, IFLA_BR_VLAN_DEFAULT_PVID, br->default_pvid))
 		return -EMSGSIZE;
 #endif
 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING

net/bridge/br_private.h

@@ -690,6 +690,7 @@ int __br_vlan_set_proto(struct net_bridge *br, __be16 proto);
 int br_vlan_set_proto(struct net_bridge *br, unsigned long val);
 int br_vlan_init(struct net_bridge *br);
 int br_vlan_set_default_pvid(struct net_bridge *br, unsigned long val);
+int __br_vlan_set_default_pvid(struct net_bridge *br, u16 pvid);
 int nbp_vlan_add(struct net_bridge_port *port, u16 vid, u16 flags);
 int nbp_vlan_delete(struct net_bridge_port *port, u16 vid);
 void nbp_vlan_flush(struct net_bridge_port *port);

net/bridge/br_vlan.c

@@ -727,7 +727,7 @@ static void br_vlan_disable_default_pvid(struct net_bridge *br)
 	br->default_pvid = 0;
 }
 
-static int __br_vlan_set_default_pvid(struct net_bridge *br, u16 pvid)
+int __br_vlan_set_default_pvid(struct net_bridge *br, u16 pvid)
 {
 	const struct net_bridge_vlan *pvent;
 	struct net_bridge_port *p;
@@ -735,6 +735,11 @@ static int __br_vlan_set_default_pvid(struct net_bridge *br, u16 pvid)
 	int err = 0;
 	unsigned long *changed;
 
+	if (!pvid) {
+		br_vlan_disable_default_pvid(br);
+		return 0;
+	}
+
 	changed = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
 			  GFP_KERNEL);
 	if (!changed)
@@ -825,12 +830,7 @@ int br_vlan_set_default_pvid(struct net_bridge *br, unsigned long val)
 		err = -EPERM;
 		goto unlock;
 	}
-
-	if (!pvid)
-		br_vlan_disable_default_pvid(br);
-	else
-		err = __br_vlan_set_default_pvid(br, pvid);
-
+	err = __br_vlan_set_default_pvid(br, pvid);
 unlock:
 	rtnl_unlock();
 	return err;