vlan: make a new function vlan_dev_vlan_proto() and export

The vlan support 2 proto: 802.1q and 802.1ad, so make a new function
called vlan_dev_vlan_proto() which could return the vlan proto for
input dev.

Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 0 deletions

diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index d3d2306f00bf..13bbbde00e68 100644
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -110,6 +110,7 @@ extern struct net_device *__vlan_find_dev_deep(struct net_device *real_dev,
                                                __be16 vlan_proto, u16 vlan_id);
 extern struct net_device *vlan_dev_real_dev(const struct net_device *dev);
 extern u16 vlan_dev_vlan_id(const struct net_device *dev);
+extern __be16 vlan_dev_vlan_proto(const struct net_device *dev);
 
 /**
  *      struct vlan_priority_tci_mapping - vlan egress priority mappings
@@ -216,6 +217,12 @@ static inline u16 vlan_dev_vlan_id(const struct net_device *dev)
         return 0;
 }
 
+static inline __be16 vlan_dev_vlan_proto(const struct net_device *dev)
+{
+        BUG();
+        return 0;
+}
+
 static inline u16 vlan_dev_get_egress_qos_mask(struct net_device *dev,
                                                u32 skprio)
 {