[IPv4/IPv6]: UFO Scatter-gather approach

[safe/jmp/linux-2.6] / net / ipv6 / ip6_output.c

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 563b442..614296a 100644 (file)
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -147,7 +147,8 @@ static int ip6_output2(struct sk_buff *skb)
 
 int ip6_output(struct sk_buff *skb)
 {
-       if (skb->len > dst_mtu(skb->dst) || dst_allfrag(skb->dst))
+       if ((skb->len > dst_mtu(skb->dst) && !skb_shinfo(skb)->ufo_size) ||
+                               dst_allfrag(skb->dst))
                return ip6_fragment(skb, ip6_output2);
        else
                return ip6_output2(skb);
@@ -768,6 +769,65 @@ out_err_release:
        *dst = NULL;
        return err;
 }
+inline int ip6_ufo_append_data(struct sock *sk,
+                       int getfrag(void *from, char *to, int offset, int len,
+                       int odd, struct sk_buff *skb),
+                       void *from, int length, int hh_len, int fragheaderlen,
+                       int transhdrlen, int mtu,unsigned int flags)
+
+{
+       struct sk_buff *skb;
+       int err;
+
+       /* There is support for UDP large send offload by network
+        * device, so create one single skb packet containing complete
+        * udp datagram
+        */
+       if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) {
+               skb = sock_alloc_send_skb(sk,
+                       hh_len + fragheaderlen + transhdrlen + 20,
+                       (flags & MSG_DONTWAIT), &err);
+               if (skb == NULL)
+                       return -ENOMEM;
+
+               /* reserve space for Hardware header */
+               skb_reserve(skb, hh_len);
+
+               /* create space for UDP/IP header */
+               skb_put(skb,fragheaderlen + transhdrlen);
+
+               /* initialize network header pointer */
+               skb->nh.raw = skb->data;
+
+               /* initialize protocol header pointer */
+               skb->h.raw = skb->data + fragheaderlen;
+
+               skb->ip_summed = CHECKSUM_HW;
+               skb->csum = 0;
+               sk->sk_sndmsg_off = 0;
+       }
+
+       err = skb_append_datato_frags(sk,skb, getfrag, from,
+                                     (length - transhdrlen));
+       if (!err) {
+               struct frag_hdr fhdr;
+
+               /* specify the length of each IP datagram fragment*/
+               skb_shinfo(skb)->ufo_size = (mtu - fragheaderlen) - 
+                                               sizeof(struct frag_hdr);
+               ipv6_select_ident(skb, &fhdr);
+               skb_shinfo(skb)->ip6_frag_id = fhdr.identification;
+               __skb_queue_tail(&sk->sk_write_queue, skb);
+
+               return 0;
+       }
+       /* There is not enough support do UPD LSO,
+        * so follow normal path
+        */
+       kfree_skb(skb);
+
+       return err;
+}
 
 int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
        int offset, int len, int odd, struct sk_buff *skb),
@@ -860,6 +920,15 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
         */
 
        inet->cork.length += length;
+       if (((length > mtu) && (sk->sk_protocol == IPPROTO_UDP)) &&
+           (rt->u.dst.dev->features & NETIF_F_UFO)) {
+
+               if(ip6_ufo_append_data(sk, getfrag, from, length, hh_len,
+                               fragheaderlen, transhdrlen, mtu, flags))
+                       goto error;
+
+               return 0;
+       }
 
        if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL)
                goto alloc_new_skb;