vlan: introduce *vlan_hwaccel_push_inside helpers

Use them to push skb->vlan_tci into the payload and avoid code
duplication.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/vxlan.c

@@ -1599,14 +1599,9 @@ static int vxlan6_xmit_skb(struct vxlan_sock *vs,
 	if (unlikely(err))
 		return err;
 
-	if (vlan_tx_tag_present(skb)) {
+	skb = vlan_hwaccel_push_inside(skb);
-		skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
+	if (WARN_ON(!skb))
-						vlan_tx_tag_get(skb));
+		return -ENOMEM;
-		if (WARN_ON(!skb))
-			return -ENOMEM;
-
-		skb->vlan_tci = 0;
-	}
 
 	vxh = (struct vxlanhdr *) __skb_push(skb, sizeof(*vxh));
 	vxh->vx_flags = htonl(VXLAN_FLAGS);
@@ -1643,14 +1638,9 @@ int vxlan_xmit_skb(struct vxlan_sock *vs,
 	if (unlikely(err))
 		return err;
 
-	if (vlan_tx_tag_present(skb)) {
+	skb = vlan_hwaccel_push_inside(skb);
-		skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
+	if (WARN_ON(!skb))
-						vlan_tx_tag_get(skb));
+		return -ENOMEM;
-		if (WARN_ON(!skb))
-			return -ENOMEM;
-
-		skb->vlan_tci = 0;
-	}
 
 	vxh = (struct vxlanhdr *) __skb_push(skb, sizeof(*vxh));
 	vxh->vx_flags = htonl(VXLAN_FLAGS);

include/linux/if_vlan.h

@@ -341,6 +341,40 @@ static inline struct sk_buff *vlan_insert_tag_set_proto(struct sk_buff *skb,
 	return skb;
 }
 
+/*
+ * __vlan_hwaccel_push_inside - pushes vlan tag to the payload
+ * @skb: skbuff to tag
+ *
+ * Pushes the VLAN tag from @skb->vlan_tci inside to the payload.
+ *
+ * Following the skb_unshare() example, in case of error, the calling function
+ * doesn't have to worry about freeing the original skb.
+ */
+static inline struct sk_buff *__vlan_hwaccel_push_inside(struct sk_buff *skb)
+{
+	skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
+					vlan_tx_tag_get(skb));
+	if (likely(skb))
+		skb->vlan_tci = 0;
+	return skb;
+}
+/*
+ * vlan_hwaccel_push_inside - pushes vlan tag to the payload
+ * @skb: skbuff to tag
+ *
+ * Checks is tag is present in @skb->vlan_tci and if it is, it pushes the
+ * VLAN tag from @skb->vlan_tci inside to the payload.
+ *
+ * Following the skb_unshare() example, in case of error, the calling function
+ * doesn't have to worry about freeing the original skb.
+ */
+static inline struct sk_buff *vlan_hwaccel_push_inside(struct sk_buff *skb)
+{
+	if (vlan_tx_tag_present(skb))
+		skb = __vlan_hwaccel_push_inside(skb);
+	return skb;
+}
+
 /**
  * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
  * @skb: skbuff to tag

net/core/dev.c

@@ -2644,12 +2644,8 @@ static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
 					  netdev_features_t features)
 {
 	if (vlan_tx_tag_present(skb) &&
-	    !vlan_hw_offload_capable(features, skb->vlan_proto)) {
+	    !vlan_hw_offload_capable(features, skb->vlan_proto))
-		skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
+		skb = __vlan_hwaccel_push_inside(skb);
-						vlan_tx_tag_get(skb));
-		if (skb)
-			skb->vlan_tci = 0;
-	}
 	return skb;
 }
 

net/core/netpoll.c

@@ -79,8 +79,7 @@ static int netpoll_start_xmit(struct sk_buff *skb, struct net_device *dev,
 
 	if (vlan_tx_tag_present(skb) &&
 	    !vlan_hw_offload_capable(features, skb->vlan_proto)) {
-		skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
+		skb = __vlan_hwaccel_push_inside(skb);
-						vlan_tx_tag_get(skb));
 		if (unlikely(!skb)) {
 			/* This is actually a packet drop, but we
 			 * don't want the code that calls this
@@ -88,7 +87,6 @@ static int netpoll_start_xmit(struct sk_buff *skb, struct net_device *dev,
 			 */
 			goto out;
 		}
-		skb->vlan_tci = 0;
 	}
 
 	status = netdev_start_xmit(skb, dev, txq, false);

net/ipv4/geneve.c

@@ -131,14 +131,9 @@ int geneve_xmit_skb(struct geneve_sock *gs, struct rtable *rt,
 	if (unlikely(err))
 		return err;
 
-	if (vlan_tx_tag_present(skb)) {
+	skb = vlan_hwaccel_push_inside(skb);
-		skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
+	if (unlikely(!skb))
-						vlan_tx_tag_get(skb));
+		return -ENOMEM;
-		if (unlikely(!skb)
-			return -ENOMEM;
-
-		skb->vlan_tci = 0;
-	}
 
 	gnvh = (struct genevehdr *)__skb_push(skb, sizeof(*gnvh) + opt_len);
 	geneve_build_header(gnvh, tun_flags, vni, opt_len, opt);

net/openvswitch/datapath.c

@@ -425,12 +425,10 @@ static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
 		if (!nskb)
 			return -ENOMEM;
 
-		nskb = vlan_insert_tag_set_proto(nskb, nskb->vlan_proto,
+		nskb = __vlan_hwaccel_push_inside(nskb);
-						 vlan_tx_tag_get(nskb));
 		if (!nskb)
 			return -ENOMEM;
 
-		nskb->vlan_tci = 0;
 		skb = nskb;
 	}
 

net/openvswitch/vport-gre.c

@@ -175,14 +175,10 @@ static int gre_tnl_send(struct vport *vport, struct sk_buff *skb)
 			goto err_free_rt;
 	}
 
-	if (vlan_tx_tag_present(skb)) {
+	skb = vlan_hwaccel_push_inside(skb);
-		skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
+	if (unlikely(!skb)) {
-						vlan_tx_tag_get(skb));
+		err = -ENOMEM;
-		if (unlikely(!skb) {
+		goto err_free_rt;
-			err = -ENOMEM;
-			goto err_free_rt;
-		}
-		skb->vlan_tci = 0;
 	}
 
 	/* Push Tunnel header. */