net: vlan: prepare for 802.1ad support

Make the encapsulation protocol value a property of VLAN devices and change
the device lookup functions to take the protocol value into account.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/8021q/vlan_mvrp.c b/net/8021q/vlan_mvrp.c
index d9ec1d5..e0fe091 100644
--- a/net/8021q/vlan_mvrp.c
+++ b/net/8021q/vlan_mvrp.c
@@ -38,6 +38,8 @@
 	const struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
 	__be16 vlan_id = htons(vlan->vlan_id);
 
+	if (vlan->vlan_proto != htons(ETH_P_8021Q))
+		return 0;
 	return mrp_request_join(vlan->real_dev, &vlan_mrp_app,
 				&vlan_id, sizeof(vlan_id), MVRP_ATTR_VID);
 }
@@ -47,6 +49,8 @@
 	const struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
 	__be16 vlan_id = htons(vlan->vlan_id);
 
+	if (vlan->vlan_proto != htons(ETH_P_8021Q))
+		return;
 	mrp_request_leave(vlan->real_dev, &vlan_mrp_app,
 			  &vlan_id, sizeof(vlan_id), MVRP_ATTR_VID);
 }