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, 6 insertions, 0 deletions

diff --git a/net/8021q/vlan_core.c b/net/8021q/vlan_core.c
index 35b3c192d7b9..3c32bd257b73 100644
--- a/net/8021q/vlan_core.c
+++ b/net/8021q/vlan_core.c
@@ -106,6 +106,12 @@ u16 vlan_dev_vlan_id(const struct net_device *dev)
 }
 EXPORT_SYMBOL(vlan_dev_vlan_id);
 
+__be16 vlan_dev_vlan_proto(const struct net_device *dev)
+{
+        return vlan_dev_priv(dev)->vlan_proto;
+}
+EXPORT_SYMBOL(vlan_dev_vlan_proto);
+
 static struct sk_buff *vlan_reorder_header(struct sk_buff *skb)
 {
         if (skb_cow(skb, skb_headroom(skb)) < 0)