net: socket infrastructure for SO_TIMESTAMPING

[net-next-2.6.git] / net / ipv4 / ip_output.c

diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index d2a8f8bb78a677e5be6b9e39a4f2fe7c3b181a27..8ebe86dd72af159e2250bc315251cf61561cc38a 100644 (file)
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -430,7 +430,7 @@ static void ip_copy_metadata(struct sk_buff *to, struct sk_buff *from)
  *     single device frame, and queue such a frame for sending.
  */
 
-int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff*))
+int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
 {
        struct iphdr *iph;
        int raw = 0;
@@ -720,7 +720,7 @@ static inline int ip_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)
+                       int transhdrlen, int mtu, unsigned int flags)
 {
        struct sk_buff *skb;
        int err;
@@ -741,7 +741,7 @@ static inline int ip_ufo_append_data(struct sock *sk,
                skb_reserve(skb, hh_len);
 
                /* create space for UDP/IP header */
-               skb_put(skb,fragheaderlen + transhdrlen);
+               skb_put(skb, fragheaderlen + transhdrlen);
 
                /* initialize network header pointer */
                skb_reset_network_header(skb);
@@ -778,7 +778,7 @@ int ip_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 transhdrlen,
-                  struct ipcm_cookie *ipc, struct rtable *rt,
+                  struct ipcm_cookie *ipc, struct rtable **rtp,
                   unsigned int flags)
 {
        struct inet_sock *inet = inet_sk(sk);
@@ -793,6 +793,7 @@ int ip_append_data(struct sock *sk,
        int offset = 0;
        unsigned int maxfraglen, fragheaderlen;
        int csummode = CHECKSUM_NONE;
+       struct rtable *rt;
 
        if (flags&MSG_PROBE)
                return 0;
@@ -812,7 +813,11 @@ int ip_append_data(struct sock *sk,
                        inet->cork.flags |= IPCORK_OPT;
                        inet->cork.addr = ipc->addr;
                }
-               dst_hold(&rt->u.dst);
+               rt = *rtp;
+               /*
+                * We steal reference to this route, caller should not release it
+                */
+               *rtp = NULL;
                inet->cork.fragsize = mtu = inet->pmtudisc == IP_PMTUDISC_PROBE ?
                                            rt->u.dst.dev->mtu :
                                            dst_mtu(rt->u.dst.path);
@@ -1279,7 +1284,12 @@ int ip_push_pending_frames(struct sock *sk)
 
        skb->priority = sk->sk_priority;
        skb->mark = sk->sk_mark;
-       skb->dst = dst_clone(&rt->u.dst);
+       /*
+        * Steal rt from cork.dst to avoid a pair of atomic_inc/atomic_dec
+        * on dst refcount
+        */
+       inet->cork.dst = NULL;
+       skb->dst = &rt->u.dst;
 
        if (iph->protocol == IPPROTO_ICMP)
                icmp_out_count(net, ((struct icmphdr *)
@@ -1391,7 +1401,7 @@ void ip_send_reply(struct sock *sk, struct sk_buff *skb, struct ip_reply_arg *ar
        sk->sk_protocol = ip_hdr(skb)->protocol;
        sk->sk_bound_dev_if = arg->bound_dev_if;
        ip_append_data(sk, ip_reply_glue_bits, arg->iov->iov_base, len, 0,
-                      &ipc, rt, MSG_DONTWAIT);
+                      &ipc, &rt, MSG_DONTWAIT);
        if ((skb = skb_peek(&sk->sk_write_queue)) != NULL) {
                if (arg->csumoffset >= 0)
                        *((__sum16 *)skb_transport_header(skb) +