inet: add IPv6 support to sk_ehashfn()

Intent is to converge IPv4 & IPv6 inet_hash functions to
factorize code.

IPv4 sockets initialize sk_rcv_saddr and sk_v6_daddr
in this patch, thanks to new sk_daddr_set() and sk_rcv_saddr_set()
helpers.

__inet6_hash can now use sk_ehashfn() instead of a private
inet6_sk_ehashfn() and will simply use __inet_hash() in a
following patch.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
index df7df99..ed5787b 100644
--- a/net/ipv6/inet6_hashtables.c
+++ b/net/ipv6/inet6_hashtables.c
@@ -23,11 +23,9 @@
 #include <net/secure_seq.h>
 #include <net/ip.h>
 
-static u32 inet6_ehashfn(const struct net *net,
-			 const struct in6_addr *laddr,
-			 const u16 lport,
-			 const struct in6_addr *faddr,
-			 const __be16 fport)
+u32 inet6_ehashfn(const struct net *net,
+		  const struct in6_addr *laddr, const u16 lport,
+		  const struct in6_addr *faddr, const __be16 fport)
 {
 	static u32 inet6_ehash_secret __read_mostly;
 	static u32 ipv6_hash_secret __read_mostly;
@@ -44,18 +42,6 @@
 			       inet6_ehash_secret + net_hash_mix(net));
 }
 
-static int inet6_sk_ehashfn(const struct sock *sk)
-{
-	const struct inet_sock *inet = inet_sk(sk);
-	const struct in6_addr *laddr = &sk->sk_v6_rcv_saddr;
-	const struct in6_addr *faddr = &sk->sk_v6_daddr;
-	const __u16 lport = inet->inet_num;
-	const __be16 fport = inet->inet_dport;
-	struct net *net = sock_net(sk);
-
-	return inet6_ehashfn(net, laddr, lport, faddr, fport);
-}
-
 int __inet6_hash(struct sock *sk, struct inet_timewait_sock *tw)
 {
 	struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
@@ -75,7 +61,7 @@
 		struct hlist_nulls_head *list;
 		spinlock_t *lock;
 
-		sk->sk_hash = hash = inet6_sk_ehashfn(sk);
+		sk->sk_hash = hash = sk_ehashfn(sk);
 		list = &inet_ehash_bucket(hashinfo, hash)->chain;
 		lock = inet_ehash_lockp(hashinfo, hash);
 		spin_lock(lock);