sctp: clean up route lookup calls

Change the call to take the transport parameter and set the
cached 'dst' appropriately inside the get_dst() function calls.

This will allow us in the future  to clean up source address
storage as well.

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>
diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c
index a1913a4..500875f 100644
--- a/net/sctp/ipv6.c
+++ b/net/sctp/ipv6.c
@@ -247,17 +247,16 @@
 /* Returns the dst cache entry for the given source and destination ip
  * addresses.
  */
-static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
-					 union sctp_addr *daddr,
-					 union sctp_addr *saddr,
-					 struct flowi *fl,
-					 struct sock *sk)
+static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
+			    struct flowi *fl, struct sock *sk)
 {
+	struct sctp_association *asoc = t->asoc;
 	struct dst_entry *dst = NULL;
 	struct flowi6 *fl6 = &fl->u.ip6;
 	struct sctp_bind_addr *bp;
 	struct sctp_sockaddr_entry *laddr;
 	union sctp_addr *baddr = NULL;
+	union sctp_addr *daddr = &t->ipaddr;
 	union sctp_addr dst_saddr;
 	__u8 matchlen = 0;
 	__u8 bmatchlen;
@@ -270,7 +269,6 @@
 	if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 		fl6->flowi6_oif = daddr->v6.sin6_scope_id;
 
-
 	SCTP_DEBUG_PRINTK("%s: DST=%pI6 ", __func__, &fl6->daddr);
 
 	if (asoc)
@@ -343,12 +341,13 @@
 	if (!IS_ERR(dst)) {
 		struct rt6_info *rt;
 		rt = (struct rt6_info *)dst;
+		t->dst = dst;
 		SCTP_DEBUG_PRINTK("rt6_dst:%pI6 rt6_src:%pI6\n",
 			&rt->rt6i_dst.addr, &fl6->saddr);
-		return dst;
+	} else {
+		t->dst = NULL;
+		SCTP_DEBUG_PRINTK("NO ROUTE\n");
 	}
-	SCTP_DEBUG_PRINTK("NO ROUTE\n");
-	return NULL;
 }
 
 /* Returns the number of consecutive initial bits that match in the 2 ipv6