ipv6: make lookups simpler and faster

TCP listener refactoring, part 4 :

To speed up inet lookups, we moved IPv4 addresses from inet to struct
sock_common

Now is time to do the same for IPv6, because it permits us to have fast
lookups for all kind of sockets, including upcoming SYN_RECV.

Getting IPv6 addresses in TCP lookups currently requires two extra cache
lines, plus a dereference (and memory stall).

inet6_sk(sk) does the dereference of inet_sk(__sk)->pinet6

This patch is way bigger than its IPv4 counter part, because for IPv4,
we could add aliases (inet_daddr, inet_rcv_saddr), while on IPv6,
it's not doable easily.

inet6_sk(sk)->daddr becomes sk->sk_v6_daddr
inet6_sk(sk)->rcv_saddr becomes sk->sk_v6_rcv_saddr

And timewait socket also have tw->tw_v6_daddr & tw->tw_v6_rcv_saddr
at the same offset.

We get rid of INET6_TW_MATCH() as INET6_MATCH() is now the generic
macro.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/security/lsm_audit.c b/security/lsm_audit.c
index 8d8d97d..80554fc 100644
--- a/security/lsm_audit.c
+++ b/security/lsm_audit.c
@@ -304,12 +304,11 @@
 			}
 			case AF_INET6: {
 				struct inet_sock *inet = inet_sk(sk);
-				struct ipv6_pinfo *inet6 = inet6_sk(sk);
 
-				print_ipv6_addr(ab, &inet6->rcv_saddr,
+				print_ipv6_addr(ab, &sk->sk_v6_rcv_saddr,
 						inet->inet_sport,
 						"laddr", "lport");
-				print_ipv6_addr(ab, &inet6->daddr,
+				print_ipv6_addr(ab, &sk->sk_v6_daddr,
 						inet->inet_dport,
 						"faddr", "fport");
 				break;