gro: Avoid copying headers of unmerged packets

[safe/jmp/linux-2.6] / net / core / skbuff.c

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 2e5f2ca..f9f4065 100644 (file)
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -2584,17 +2584,21 @@ int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb)
        struct sk_buff *p = *head;
        struct sk_buff *nskb;
        unsigned int headroom;
-       unsigned int hlen = p->data - skb_mac_header(p);
-       unsigned int len = skb->len;
+       unsigned int len = skb_gro_len(skb);
 
-       if (hlen + p->len + len >= 65536)
+       if (p->len + len >= 65536)
                return -E2BIG;
 
        if (skb_shinfo(p)->frag_list)
                goto merge;
-       else if (!skb_headlen(p) && !skb_headlen(skb) &&
-                skb_shinfo(p)->nr_frags + skb_shinfo(skb)->nr_frags <
+       else if (skb_headlen(skb) <= skb_gro_offset(skb) &&
+                skb_shinfo(p)->nr_frags + skb_shinfo(skb)->nr_frags <=
                 MAX_SKB_FRAGS) {
+               skb_shinfo(skb)->frags[0].page_offset +=
+                       skb_gro_offset(skb) - skb_headlen(skb);
+               skb_shinfo(skb)->frags[0].size -=
+                       skb_gro_offset(skb) - skb_headlen(skb);
+
                memcpy(skb_shinfo(p)->frags + skb_shinfo(p)->nr_frags,
                       skb_shinfo(skb)->frags,
                       skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t));
@@ -2611,7 +2615,7 @@ int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb)
        }
 
        headroom = skb_headroom(p);
-       nskb = netdev_alloc_skb(p->dev, headroom);
+       nskb = netdev_alloc_skb(p->dev, headroom + skb_gro_offset(p));
        if (unlikely(!nskb))
                return -ENOMEM;
 
@@ -2619,12 +2623,15 @@ int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb)
        nskb->mac_len = p->mac_len;
 
        skb_reserve(nskb, headroom);
+       __skb_put(nskb, skb_gro_offset(p));
 
-       skb_set_mac_header(nskb, -hlen);
+       skb_set_mac_header(nskb, skb_mac_header(p) - p->data);
        skb_set_network_header(nskb, skb_network_offset(p));
        skb_set_transport_header(nskb, skb_transport_offset(p));
 
-       memcpy(skb_mac_header(nskb), skb_mac_header(p), hlen);
+       __skb_pull(p, skb_gro_offset(p));
+       memcpy(skb_mac_header(nskb), skb_mac_header(p),
+              p->data - skb_mac_header(p));
 
        *NAPI_GRO_CB(nskb) = *NAPI_GRO_CB(p);
        skb_shinfo(nskb)->frag_list = p;