ipv4: Add a socket release callback for datagram sockets
[~shefty/rdma-dev.git] / net / ipv4 / datagram.c
index 424fafbc8cb02c49fb2dd3551f3583290f2fc330..b28e863fe0a7143b199bee51cfdf242c125f31cf 100644 (file)
@@ -85,3 +85,28 @@ out:
        return err;
 }
 EXPORT_SYMBOL(ip4_datagram_connect);
+
+void ip4_datagram_release_cb(struct sock *sk)
+{
+       const struct inet_sock *inet = inet_sk(sk);
+       const struct ip_options_rcu *inet_opt;
+       __be32 daddr = inet->inet_daddr;
+       struct flowi4 fl4;
+       struct rtable *rt;
+
+       if (! __sk_dst_get(sk) || __sk_dst_check(sk, 0))
+               return;
+
+       rcu_read_lock();
+       inet_opt = rcu_dereference(inet->inet_opt);
+       if (inet_opt && inet_opt->opt.srr)
+               daddr = inet_opt->opt.faddr;
+       rt = ip_route_output_ports(sock_net(sk), &fl4, sk, daddr,
+                                  inet->inet_saddr, inet->inet_dport,
+                                  inet->inet_sport, sk->sk_protocol,
+                                  RT_CONN_FLAGS(sk), sk->sk_bound_dev_if);
+       if (!IS_ERR(rt))
+               __sk_dst_set(sk, &rt->dst);
+       rcu_read_unlock();
+}
+EXPORT_SYMBOL_GPL(ip4_datagram_release_cb);