vlan: Move vlan_set_encap_proto() to vlan header file

Open vSwitch needs this function for vlan handling.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

1 files changed, 34 insertions, 0 deletions

diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index 12d5543b14f2..070ac50c1d2d 100644
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -310,6 +310,40 @@ static inline __be16 vlan_get_protocol(const struct sk_buff *skb)
 
         return protocol;
 }
+
+static inline void vlan_set_encap_proto(struct sk_buff *skb,
+                                        struct vlan_hdr *vhdr)
+{
+        __be16 proto;
+        unsigned char *rawp;
+
+        /*
+         * Was a VLAN packet, grab the encapsulated protocol, which the layer
+         * three protocols care about.
+         */
+
+        proto = vhdr->h_vlan_encapsulated_proto;
+        if (ntohs(proto) >= 1536) {
+                skb->protocol = proto;
+                return;
+        }
+
+        rawp = skb->data;
+        if (*(unsigned short *) rawp == 0xFFFF)
+                /*
+                 * This is a magic hack to spot IPX packets. Older Novell
+                 * breaks the protocol design and runs IPX over 802.3 without
+                 * an 802.2 LLC layer. We look for FFFF which isn't a used
+                 * 802.2 SSAP/DSAP. This won't work for fault tolerant netware
+                 * but does for the rest.
+                 */
+                skb->protocol = htons(ETH_P_802_3);
+        else
+                /*
+                 * Real 802.2 LLC
+                 */
+                skb->protocol = htons(ETH_P_802_2);
+}
 #endif /* __KERNEL__ */
 
 /* VLAN IOCTLs are found in sockios.h */