net: move vlan pop/push functions into common code

So it can be used from out of openvswitch code.
Did couple of cosmetic changes on the way, namely variable naming and
adding support for 8021AD proto.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 77 deletions

diff --git a/net/openvswitch/actions.c b/net/openvswitch/actions.c
index 7ffa377..4e05ea1 100644
--- a/net/openvswitch/actions.c
+++ b/net/openvswitch/actions.c
@@ -206,93 +206,27 @@ static int set_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 	return 0;
 }
 
-/* remove VLAN header from packet and update csum accordingly. */
-static int __pop_vlan_tci(struct sk_buff *skb, __be16 *current_tci)
-{
-	struct vlan_hdr *vhdr;
-	int err;
-
-	err = skb_ensure_writable(skb, VLAN_ETH_HLEN);
-	if (unlikely(err))
-		return err;
-
-	skb_postpull_rcsum(skb, skb->data + (2 * ETH_ALEN), VLAN_HLEN);
-
-	vhdr = (struct vlan_hdr *)(skb->data + ETH_HLEN);
-	*current_tci = vhdr->h_vlan_TCI;
-
-	memmove(skb->data + VLAN_HLEN, skb->data, 2 * ETH_ALEN);
-	__skb_pull(skb, VLAN_HLEN);
-
-	vlan_set_encap_proto(skb, vhdr);
-	skb->mac_header += VLAN_HLEN;
-
-	if (skb_network_offset(skb) < ETH_HLEN)
-		skb_set_network_header(skb, ETH_HLEN);
-
-	/* Update mac_len for subsequent MPLS actions */
-	skb_reset_mac_len(skb);
-	return 0;
-}
-
 static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 {
-	__be16 tci;
 	int err;
 
-	if (likely(vlan_tx_tag_present(skb))) {
-		skb->vlan_tci = 0;
-	} else {
-		if (unlikely(skb->protocol != htons(ETH_P_8021Q) ||
-			     skb->len < VLAN_ETH_HLEN))
-			return 0;
-
-		err = __pop_vlan_tci(skb, &tci);
-		if (err)
-			return err;
-	}
-	/* move next vlan tag to hw accel tag */
-	if (likely(skb->protocol != htons(ETH_P_8021Q) ||
-		   skb->len < VLAN_ETH_HLEN)) {
+	err = skb_vlan_pop(skb);
+	if (vlan_tx_tag_present(skb))
+		invalidate_flow_key(key);
+	else
 		key->eth.tci = 0;
-		return 0;
-	}
-
-	invalidate_flow_key(key);
-	err = __pop_vlan_tci(skb, &tci);
-	if (unlikely(err))
-		return err;
-
-	__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), ntohs(tci));
-	return 0;
+	return err;
 }
 
 static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key,
 		     const struct ovs_action_push_vlan *vlan)
 {
-	if (unlikely(vlan_tx_tag_present(skb))) {
-		u16 current_tag;
-
-		/* push down current VLAN tag */
-		current_tag = vlan_tx_tag_get(skb);
-
-		skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
-						current_tag);
-		if (!skb)
-			return -ENOMEM;
-		/* Update mac_len for subsequent MPLS actions */
-		skb->mac_len += VLAN_HLEN;
-
-		if (skb->ip_summed == CHECKSUM_COMPLETE)
-			skb->csum = csum_add(skb->csum, csum_partial(skb->data
-					+ (2 * ETH_ALEN), VLAN_HLEN, 0));
-
+	if (vlan_tx_tag_present(skb))
 		invalidate_flow_key(key);
-	} else {
+	else
 		key->eth.tci = vlan->vlan_tci;
-	}
-	__vlan_hwaccel_put_tag(skb, vlan->vlan_tpid, ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT);
-	return 0;
+	return skb_vlan_push(skb, vlan->vlan_tpid,
+			     ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT);
 }
 
 static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *key,
@@ -858,8 +792,6 @@ static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
 
 		case OVS_ACTION_ATTR_PUSH_VLAN:
 			err = push_vlan(skb, key, nla_data(a));
-			if (unlikely(err)) /* skb already freed. */
-				return err;
 			break;
 
 		case OVS_ACTION_ATTR_POP_VLAN: