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>

7 files changed, 51 insertions, 44 deletions

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index bb8fbab438e8..64d45fa3d997 100644
--- a/drivers/net/vxlan.c
+++ b/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_insert_tag_set_proto(skb, skb->vlan_proto,
-                                                vlan_tx_tag_get(skb));
-                if (WARN_ON(!skb))
-                        return -ENOMEM;
-
-                skb->vlan_tci = 0;
-        }
+        skb = vlan_hwaccel_push_inside(skb);
+        if (WARN_ON(!skb))
+                return -ENOMEM;
 
         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_insert_tag_set_proto(skb, skb->vlan_proto,
-                                                vlan_tx_tag_get(skb));
-                if (WARN_ON(!skb))
-                        return -ENOMEM;
-
-                skb->vlan_tci = 0;
-        }
+        skb = vlan_hwaccel_push_inside(skb);
+        if (WARN_ON(!skb))
+                return -ENOMEM;
 
         vxh = (struct vxlanhdr *) __skb_push(skb, sizeof(*vxh));
         vxh->vx_flags = htonl(VXLAN_FLAGS);
diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index 46e4a15b9b55..291e6706876e 100644
--- a/include/linux/if_vlan.h
+++ b/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
diff --git a/net/core/dev.c b/net/core/dev.c
index 3611e60df407..ac4836241a96 100644
--- a/net/core/dev.c
+++ b/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)) {
-                skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
-                                                vlan_tx_tag_get(skb));
-                if (skb)
-                        skb->vlan_tci = 0;
-        }
+            !vlan_hw_offload_capable(features, skb->vlan_proto))
+                skb = __vlan_hwaccel_push_inside(skb);
         return skb;
 }
 
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index 65d372384a3f..e0ad5d16c9c5 100644
--- a/net/core/netpoll.c
+++ b/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,
-                                                vlan_tx_tag_get(skb));
+                skb = __vlan_hwaccel_push_inside(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);
diff --git a/net/ipv4/geneve.c b/net/ipv4/geneve.c
index fd430a6a1c37..a457232f0131 100644
--- a/net/ipv4/geneve.c
+++ b/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_insert_tag_set_proto(skb, skb->vlan_proto,
-                                                vlan_tx_tag_get(skb));
-                if (unlikely(!skb)
-                        return -ENOMEM;
-
-                skb->vlan_tci = 0;
-        }
+        skb = vlan_hwaccel_push_inside(skb);
+        if (unlikely(!skb))
+                return -ENOMEM;
 
         gnvh = (struct genevehdr *)__skb_push(skb, sizeof(*gnvh) + opt_len);
         geneve_build_header(gnvh, tun_flags, vni, opt_len, opt);
diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index c63e60e4d947..f37ca3e5824c 100644
--- a/net/openvswitch/datapath.c
+++ b/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,
-                                                 vlan_tx_tag_get(nskb));
+                nskb = __vlan_hwaccel_push_inside(nskb);
                 if (!nskb)
                         return -ENOMEM;
 
-                nskb->vlan_tci = 0;
                 skb = nskb;
         }
 
diff --git a/net/openvswitch/vport-gre.c b/net/openvswitch/vport-gre.c
index 777cd8c71d53..6b69df545b1d 100644
--- a/net/openvswitch/vport-gre.c
+++ b/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_insert_tag_set_proto(skb, skb->vlan_proto,
-                                                vlan_tx_tag_get(skb));
-                if (unlikely(!skb) {
-                        err = -ENOMEM;
-                        goto err_free_rt;
-                }
-                skb->vlan_tci = 0;
+        skb = vlan_hwaccel_push_inside(skb);
+        if (unlikely(!skb)) {
+                err = -ENOMEM;
+                goto err_free_rt;
         }
 
         /* Push Tunnel header. */