net: move vlan pop/push functions into common code
authorJiri Pirko <jiri@resnulli.us>
Wed, 19 Nov 2014 13:05:02 +0000 (14:05 +0100)
committerDavid S. Miller <davem@davemloft.net>
Fri, 21 Nov 2014 19:20:18 +0000 (14:20 -0500)
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>
include/linux/skbuff.h
net/core/skbuff.c
net/openvswitch/actions.c

index e045516891a909683ce3a3315c1cb21fe2a632d4..78c299f40baccc13f2f099e188ffb3a5dcdc0c26 100644 (file)
@@ -2679,6 +2679,8 @@ unsigned int skb_gso_transport_seglen(const struct sk_buff *skb);
 struct sk_buff *skb_segment(struct sk_buff *skb, netdev_features_t features);
 struct sk_buff *skb_vlan_untag(struct sk_buff *skb);
 int skb_ensure_writable(struct sk_buff *skb, int write_len);
+int skb_vlan_pop(struct sk_buff *skb);
+int skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci);
 
 struct skb_checksum_ops {
        __wsum (*update)(const void *mem, int len, __wsum wsum);
index d11bbe0da355e6b3417dd77f3ddf04fd7faa4050..c906c5f4bf692518df26928ad54739cfdb1d358c 100644 (file)
@@ -4163,6 +4163,101 @@ int skb_ensure_writable(struct sk_buff *skb, int write_len)
 }
 EXPORT_SYMBOL(skb_ensure_writable);
 
+/* remove VLAN header from packet and update csum accordingly. */
+static int __skb_vlan_pop(struct sk_buff *skb, u16 *vlan_tci)
+{
+       struct vlan_hdr *vhdr;
+       unsigned int offset = skb->data - skb_mac_header(skb);
+       int err;
+
+       __skb_push(skb, offset);
+       err = skb_ensure_writable(skb, VLAN_ETH_HLEN);
+       if (unlikely(err))
+               goto pull;
+
+       skb_postpull_rcsum(skb, skb->data + (2 * ETH_ALEN), VLAN_HLEN);
+
+       vhdr = (struct vlan_hdr *)(skb->data + ETH_HLEN);
+       *vlan_tci = ntohs(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);
+
+       skb_reset_mac_len(skb);
+pull:
+       __skb_pull(skb, offset);
+
+       return err;
+}
+
+int skb_vlan_pop(struct sk_buff *skb)
+{
+       u16 vlan_tci;
+       __be16 vlan_proto;
+       int err;
+
+       if (likely(vlan_tx_tag_present(skb))) {
+               skb->vlan_tci = 0;
+       } else {
+               if (unlikely((skb->protocol != htons(ETH_P_8021Q) &&
+                             skb->protocol != htons(ETH_P_8021AD)) ||
+                            skb->len < VLAN_ETH_HLEN))
+                       return 0;
+
+               err = __skb_vlan_pop(skb, &vlan_tci);
+               if (err)
+                       return err;
+       }
+       /* move next vlan tag to hw accel tag */
+       if (likely((skb->protocol != htons(ETH_P_8021Q) &&
+                   skb->protocol != htons(ETH_P_8021AD)) ||
+                  skb->len < VLAN_ETH_HLEN))
+               return 0;
+
+       vlan_proto = skb->protocol;
+       err = __skb_vlan_pop(skb, &vlan_tci);
+       if (unlikely(err))
+               return err;
+
+       __vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci);
+       return 0;
+}
+EXPORT_SYMBOL(skb_vlan_pop);
+
+int skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci)
+{
+       if (vlan_tx_tag_present(skb)) {
+               unsigned int offset = skb->data - skb_mac_header(skb);
+               int err;
+
+               /* __vlan_insert_tag expect skb->data pointing to mac header.
+                * So change skb->data before calling it and change back to
+                * original position later
+                */
+               __skb_push(skb, offset);
+               err = __vlan_insert_tag(skb, skb->vlan_proto,
+                                       vlan_tx_tag_get(skb));
+               if (err)
+                       return err;
+               skb->protocol = skb->vlan_proto;
+               skb->mac_len += VLAN_HLEN;
+               __skb_pull(skb, offset);
+
+               if (skb->ip_summed == CHECKSUM_COMPLETE)
+                       skb->csum = csum_add(skb->csum, csum_partial(skb->data
+                                       + (2 * ETH_ALEN), VLAN_HLEN, 0));
+       }
+       __vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci);
+       return 0;
+}
+EXPORT_SYMBOL(skb_vlan_push);
+
 /**
  * alloc_skb_with_frags - allocate skb with page frags
  *
index 7ffa3771626569856f9997cf764bf91e3bd13502..4e05ea1c2d11c2aec9aeff98d6ff7ecdec6c6aa6 100644 (file)
@@ -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: