sctp: cache the ipv6 source after route lookup

The ipv6 routing lookup does give us a source address,
but instead of filling it into the dst, it's stored in
the flowi.  We can use that instead of going through the
entire source address selection again.
Also the useless ->dst_saddr member of sctp_pf is removed.
And sctp_v6_dst_saddr() is removed, instead by introduce
sctp_v6_to_addr(), which can be reused to cleanup some dup
code.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 5 deletions

diff --git a/net/sctp/transport.c b/net/sctp/transport.c
index d3ae493d234..2544b9b21f8 100644
--- a/net/sctp/transport.c
+++ b/net/sctp/transport.c
@@ -211,11 +211,15 @@ void sctp_transport_set_owner(struct sctp_transport *transport,
 }
 
 /* Initialize the pmtu of a transport. */
-void sctp_transport_pmtu(struct sctp_transport *transport)
+void sctp_transport_pmtu(struct sctp_transport *transport, struct sock *sk)
 {
         struct dst_entry *dst;
+        struct flowi fl;
 
-        dst = transport->af_specific->get_dst(NULL, &transport->ipaddr, NULL);
+        dst = transport->af_specific->get_dst(transport->asoc,
+                                              &transport->ipaddr,
+                                              &transport->saddr,
+                                              &fl, sk);
 
         if (dst) {
                 transport->pathmtu = dst_mtu(dst);
@@ -272,15 +276,16 @@ void sctp_transport_route(struct sctp_transport *transport,
         struct sctp_af *af = transport->af_specific;
         union sctp_addr *daddr = &transport->ipaddr;
         struct dst_entry *dst;
+        struct flowi fl;
 
-        dst = af->get_dst(asoc, daddr, saddr);
+        dst = af->get_dst(asoc, daddr, saddr, &fl, sctp_opt2sk(opt));
+        transport->dst = dst;
 
         if (saddr)
                 memcpy(&transport->saddr, saddr, sizeof(union sctp_addr));
         else
-                af->get_saddr(opt, asoc, dst, daddr, &transport->saddr);
+                af->get_saddr(opt, transport, daddr, &fl);
 
-        transport->dst = dst;
         if ((transport->param_flags & SPP_PMTUD_DISABLE) && transport->pathmtu) {
                 return;
         }