1 files changed, 73 insertions, 34 deletions

diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index d69f057..515a35e2 100644
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -282,28 +282,24 @@ static inline bool vlan_hw_offload_capable(netdev_features_t features,
 }
 
 /**
- * vlan_insert_tag - regular VLAN tag inserting
+ * __vlan_insert_tag - regular VLAN tag inserting
  * @skb: skbuff to tag
  * @vlan_proto: VLAN encapsulation protocol
  * @vlan_tci: VLAN TCI to insert
  *
  * Inserts the VLAN tag into @skb as part of the payload
- * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
- *
- * Following the skb_unshare() example, in case of error, the calling function
- * doesn't have to worry about freeing the original skb.
+ * Returns error if skb_cow_head failes.
  *
  * Does not change skb->protocol so this function can be used during receive.
  */
-static inline struct sk_buff *vlan_insert_tag(struct sk_buff *skb,
-					      __be16 vlan_proto, u16 vlan_tci)
+static inline int __vlan_insert_tag(struct sk_buff *skb,
+				    __be16 vlan_proto, u16 vlan_tci)
 {
 	struct vlan_ethhdr *veth;
 
-	if (skb_cow_head(skb, VLAN_HLEN) < 0) {
-		dev_kfree_skb_any(skb);
-		return NULL;
-	}
+	if (skb_cow_head(skb, VLAN_HLEN) < 0)
+		return -ENOMEM;
+
 	veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);
 
 	/* Move the mac addresses to the beginning of the new header. */
@@ -316,12 +312,40 @@ static inline struct sk_buff *vlan_insert_tag(struct sk_buff *skb,
 	/* now, the TCI */
 	veth->h_vlan_TCI = htons(vlan_tci);
 
+	return 0;
+}
+
+/**
+ * vlan_insert_tag - regular VLAN tag inserting
+ * @skb: skbuff to tag
+ * @vlan_proto: VLAN encapsulation protocol
+ * @vlan_tci: VLAN TCI to insert
+ *
+ * Inserts the VLAN tag into @skb as part of the payload
+ * Returns a VLAN tagged skb. If a new skb is created, @skb is freed.
+ *
+ * Following the skb_unshare() example, in case of error, the calling function
+ * doesn't have to worry about freeing the original skb.
+ *
+ * Does not change skb->protocol so this function can be used during receive.
+ */
+static inline struct sk_buff *vlan_insert_tag(struct sk_buff *skb,
+					      __be16 vlan_proto, u16 vlan_tci)
+{
+	int err;
+
+	err = __vlan_insert_tag(skb, vlan_proto, vlan_tci);
+	if (err) {
+		dev_kfree_skb_any(skb);
+		return NULL;
+	}
 	return skb;
 }
 
 /**
- * __vlan_put_tag - regular VLAN tag inserting
+ * vlan_insert_tag_set_proto - regular VLAN tag inserting
  * @skb: skbuff to tag
+ * @vlan_proto: VLAN encapsulation protocol
  * @vlan_tci: VLAN TCI to insert
  *
  * Inserts the VLAN tag into @skb as part of the payload
@@ -330,8 +354,9 @@ static inline struct sk_buff *vlan_insert_tag(struct sk_buff *skb,
  * 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_put_tag(struct sk_buff *skb,
-					     __be16 vlan_proto, u16 vlan_tci)
+static inline struct sk_buff *vlan_insert_tag_set_proto(struct sk_buff *skb,
+							__be16 vlan_proto,
+							u16 vlan_tci)
 {
 	skb = vlan_insert_tag(skb, vlan_proto, vlan_tci);
 	if (skb)
@@ -339,39 +364,53 @@ static inline struct sk_buff *__vlan_put_tag(struct sk_buff *skb,
 	return skb;
 }
 
-/**
- * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
+/*
+ * __vlan_hwaccel_push_inside - pushes vlan tag to the payload
  * @skb: skbuff to tag
- * @vlan_proto: VLAN encapsulation protocol
- * @vlan_tci: VLAN TCI to insert
  *
- * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest
+ * 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_put_tag(struct sk_buff *skb,
-						     __be16 vlan_proto,
-						     u16 vlan_tci)
+static inline struct sk_buff *__vlan_hwaccel_push_inside(struct sk_buff *skb)
 {
-	skb->vlan_proto = vlan_proto;
-	skb->vlan_tci = VLAN_TAG_PRESENT | vlan_tci;
+	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_put_tag - inserts VLAN tag according to device features
+ * __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
  * @skb: skbuff to tag
+ * @vlan_proto: VLAN encapsulation protocol
  * @vlan_tci: VLAN TCI to insert
  *
- * Assumes skb->dev is the target that will xmit this frame.
- * Returns a VLAN tagged skb.
+ * Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest
  */
-static inline struct sk_buff *vlan_put_tag(struct sk_buff *skb,
-					   __be16 vlan_proto, u16 vlan_tci)
+static inline void __vlan_hwaccel_put_tag(struct sk_buff *skb,
+					  __be16 vlan_proto, u16 vlan_tci)
 {
-	if (vlan_hw_offload_capable(skb->dev->features, vlan_proto)) {
-		return __vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci);
-	} else {
-		return __vlan_put_tag(skb, vlan_proto, vlan_tci);
-	}
+	skb->vlan_proto = vlan_proto;
+	skb->vlan_tci = VLAN_TAG_PRESENT | vlan_tci;
 }
 
 /**