inet: includes a sock_common in request_sock

TCP listener refactoring, part 5 :

We want to be able to insert request sockets (SYN_RECV) into main
ehash table instead of the per listener hash table to allow RCU
lookups and remove listener lock contention.

This patch includes the needed struct sock_common in front
of struct request_sock

This means there is no more inet6_request_sock IPv6 specific
structure.

Following inet_request_sock fields were renamed as they became
macros to reference fields from struct sock_common.
Prefix ir_ was chosen to avoid name collisions.

loc_port   -> ir_loc_port
loc_addr   -> ir_loc_addr
rmt_addr   -> ir_rmt_addr
rmt_port   -> ir_rmt_port
iif        -> ir_iif

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/inet6_connection_sock.c b/net/ipv6/inet6_connection_sock.c
index b7400b4..1317c56 100644
--- a/net/ipv6/inet6_connection_sock.c
+++ b/net/ipv6/inet6_connection_sock.c
@@ -70,20 +70,20 @@
 				      struct flowi6 *fl6,
 				      const struct request_sock *req)
 {
-	struct inet6_request_sock *treq = inet6_rsk(req);
+	struct inet_request_sock *ireq = inet_rsk(req);
 	struct ipv6_pinfo *np = inet6_sk(sk);
 	struct in6_addr *final_p, final;
 	struct dst_entry *dst;
 
 	memset(fl6, 0, sizeof(*fl6));
 	fl6->flowi6_proto = IPPROTO_TCP;
-	fl6->daddr = treq->rmt_addr;
+	fl6->daddr = ireq->ir_v6_rmt_addr;
 	final_p = fl6_update_dst(fl6, np->opt, &final);
-	fl6->saddr = treq->loc_addr;
-	fl6->flowi6_oif = treq->iif;
+	fl6->saddr = ireq->ir_v6_loc_addr;
+	fl6->flowi6_oif = ireq->ir_iif;
 	fl6->flowi6_mark = sk->sk_mark;
-	fl6->fl6_dport = inet_rsk(req)->rmt_port;
-	fl6->fl6_sport = inet_rsk(req)->loc_port;
+	fl6->fl6_dport = ireq->ir_rmt_port;
+	fl6->fl6_sport = ireq->ir_loc_port;
 	security_req_classify_flow(req, flowi6_to_flowi(fl6));
 
 	dst = ip6_dst_lookup_flow(sk, fl6, final_p, false);
@@ -129,13 +129,13 @@
 						     lopt->nr_table_entries)];
 	     (req = *prev) != NULL;
 	     prev = &req->dl_next) {
-		const struct inet6_request_sock *treq = inet6_rsk(req);
+		const struct inet_request_sock *ireq = inet_rsk(req);
 
-		if (inet_rsk(req)->rmt_port == rport &&
+		if (ireq->ir_rmt_port == rport &&
 		    req->rsk_ops->family == AF_INET6 &&
-		    ipv6_addr_equal(&treq->rmt_addr, raddr) &&
-		    ipv6_addr_equal(&treq->loc_addr, laddr) &&
-		    (!treq->iif || treq->iif == iif)) {
+		    ipv6_addr_equal(&ireq->ir_v6_rmt_addr, raddr) &&
+		    ipv6_addr_equal(&ireq->ir_v6_loc_addr, laddr) &&
+		    (!ireq->ir_iif || ireq->ir_iif == iif)) {
 			WARN_ON(req->sk != NULL);
 			*prevp = prev;
 			return req;
@@ -153,8 +153,8 @@
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
-	const u32 h = inet6_synq_hash(&inet6_rsk(req)->rmt_addr,
-				      inet_rsk(req)->rmt_port,
+	const u32 h = inet6_synq_hash(&inet_rsk(req)->ir_v6_rmt_addr,
+				      inet_rsk(req)->ir_rmt_port,
 				      lopt->hash_rnd, lopt->nr_table_entries);
 
 	reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout);
diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
index d703218..bc5698f9 100644
--- a/net/ipv6/syncookies.c
+++ b/net/ipv6/syncookies.c
@@ -150,7 +150,6 @@
 {
 	struct tcp_options_received tcp_opt;
 	struct inet_request_sock *ireq;
-	struct inet6_request_sock *ireq6;
 	struct tcp_request_sock *treq;
 	struct ipv6_pinfo *np = inet6_sk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
@@ -187,7 +186,6 @@
 		goto out;
 
 	ireq = inet_rsk(req);
-	ireq6 = inet6_rsk(req);
 	treq = tcp_rsk(req);
 	treq->listener = NULL;
 
@@ -195,22 +193,22 @@
 		goto out_free;
 
 	req->mss = mss;
-	ireq->rmt_port = th->source;
-	ireq->loc_port = th->dest;
-	ireq6->rmt_addr = ipv6_hdr(skb)->saddr;
-	ireq6->loc_addr = ipv6_hdr(skb)->daddr;
+	ireq->ir_rmt_port = th->source;
+	ireq->ir_loc_port = th->dest;
+	ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
+	ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
 	if (ipv6_opt_accepted(sk, skb) ||
 	    np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
 	    np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
 		atomic_inc(&skb->users);
-		ireq6->pktopts = skb;
+		ireq->pktopts = skb;
 	}
 
-	ireq6->iif = sk->sk_bound_dev_if;
+	ireq->ir_iif = sk->sk_bound_dev_if;
 	/* So that link locals have meaning */
 	if (!sk->sk_bound_dev_if &&
-	    ipv6_addr_type(&ireq6->rmt_addr) & IPV6_ADDR_LINKLOCAL)
-		ireq6->iif = inet6_iif(skb);
+	    ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
+		ireq->ir_iif = inet6_iif(skb);
 
 	req->expires = 0UL;
 	req->num_retrans = 0;
@@ -234,12 +232,12 @@
 		struct flowi6 fl6;
 		memset(&fl6, 0, sizeof(fl6));
 		fl6.flowi6_proto = IPPROTO_TCP;
-		fl6.daddr = ireq6->rmt_addr;
+		fl6.daddr = ireq->ir_v6_rmt_addr;
 		final_p = fl6_update_dst(&fl6, np->opt, &final);
-		fl6.saddr = ireq6->loc_addr;
+		fl6.saddr = ireq->ir_v6_loc_addr;
 		fl6.flowi6_oif = sk->sk_bound_dev_if;
 		fl6.flowi6_mark = sk->sk_mark;
-		fl6.fl6_dport = inet_rsk(req)->rmt_port;
+		fl6.fl6_dport = ireq->ir_rmt_port;
 		fl6.fl6_sport = inet_sk(sk)->inet_sport;
 		security_req_classify_flow(req, flowi6_to_flowi(&fl6));
 
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 541dfc4..db234d6 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -465,7 +465,7 @@
 			      struct request_sock *req,
 			      u16 queue_mapping)
 {
-	struct inet6_request_sock *treq = inet6_rsk(req);
+	struct inet_request_sock *ireq = inet_rsk(req);
 	struct ipv6_pinfo *np = inet6_sk(sk);
 	struct sk_buff * skb;
 	int err = -ENOMEM;
@@ -477,9 +477,10 @@
 	skb = tcp_make_synack(sk, dst, req, NULL);
 
 	if (skb) {
-		__tcp_v6_send_check(skb, &treq->loc_addr, &treq->rmt_addr);
+		__tcp_v6_send_check(skb, &ireq->ir_v6_loc_addr,
+				    &ireq->ir_v6_rmt_addr);
 
-		fl6->daddr = treq->rmt_addr;
+		fl6->daddr = ireq->ir_v6_rmt_addr;
 		skb_set_queue_mapping(skb, queue_mapping);
 		err = ip6_xmit(sk, skb, fl6, np->opt, np->tclass);
 		err = net_xmit_eval(err);
@@ -502,7 +503,7 @@
 
 static void tcp_v6_reqsk_destructor(struct request_sock *req)
 {
-	kfree_skb(inet6_rsk(req)->pktopts);
+	kfree_skb(inet_rsk(req)->pktopts);
 }
 
 #ifdef CONFIG_TCP_MD5SIG
@@ -521,7 +522,7 @@
 static struct tcp_md5sig_key *tcp_v6_reqsk_md5_lookup(struct sock *sk,
 						      struct request_sock *req)
 {
-	return tcp_v6_md5_do_lookup(sk, &inet6_rsk(req)->rmt_addr);
+	return tcp_v6_md5_do_lookup(sk, &inet_rsk(req)->ir_v6_rmt_addr);
 }
 
 static int tcp_v6_parse_md5_keys (struct sock *sk, char __user *optval,
@@ -623,8 +624,8 @@
 		saddr = &inet6_sk(sk)->saddr;
 		daddr = &sk->sk_v6_daddr;
 	} else if (req) {
-		saddr = &inet6_rsk(req)->loc_addr;
-		daddr = &inet6_rsk(req)->rmt_addr;
+		saddr = &inet_rsk(req)->ir_v6_loc_addr;
+		daddr = &inet_rsk(req)->ir_v6_rmt_addr;
 	} else {
 		const struct ipv6hdr *ip6h = ipv6_hdr(skb);
 		saddr = &ip6h->saddr;
@@ -949,7 +950,7 @@
 {
 	struct tcp_options_received tmp_opt;
 	struct request_sock *req;
-	struct inet6_request_sock *treq;
+	struct inet_request_sock *ireq;
 	struct ipv6_pinfo *np = inet6_sk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 	__u32 isn = TCP_SKB_CB(skb)->when;
@@ -994,25 +995,25 @@
 	tmp_opt.tstamp_ok = tmp_opt.saw_tstamp;
 	tcp_openreq_init(req, &tmp_opt, skb);
 
-	treq = inet6_rsk(req);
-	treq->rmt_addr = ipv6_hdr(skb)->saddr;
-	treq->loc_addr = ipv6_hdr(skb)->daddr;
+	ireq = inet_rsk(req);
+	ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
+	ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
 	if (!want_cookie || tmp_opt.tstamp_ok)
 		TCP_ECN_create_request(req, skb, sock_net(sk));
 
-	treq->iif = sk->sk_bound_dev_if;
+	ireq->ir_iif = sk->sk_bound_dev_if;
 
 	/* So that link locals have meaning */
 	if (!sk->sk_bound_dev_if &&
-	    ipv6_addr_type(&treq->rmt_addr) & IPV6_ADDR_LINKLOCAL)
-		treq->iif = inet6_iif(skb);
+	    ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
+		ireq->ir_iif = inet6_iif(skb);
 
 	if (!isn) {
 		if (ipv6_opt_accepted(sk, skb) ||
 		    np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
 		    np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
 			atomic_inc(&skb->users);
-			treq->pktopts = skb;
+			ireq->pktopts = skb;
 		}
 
 		if (want_cookie) {
@@ -1051,7 +1052,7 @@
 			 * to the moment of synflood.
 			 */
 			LIMIT_NETDEBUG(KERN_DEBUG "TCP: drop open request from %pI6/%u\n",
-				       &treq->rmt_addr, ntohs(tcp_hdr(skb)->source));
+				       &ireq->ir_v6_rmt_addr, ntohs(tcp_hdr(skb)->source));
 			goto drop_and_release;
 		}
 
@@ -1086,7 +1087,7 @@
 					  struct request_sock *req,
 					  struct dst_entry *dst)
 {
-	struct inet6_request_sock *treq;
+	struct inet_request_sock *ireq;
 	struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 	struct tcp6_sock *newtcp6sk;
 	struct inet_sock *newinet;
@@ -1151,7 +1152,7 @@
 		return newsk;
 	}
 
-	treq = inet6_rsk(req);
+	ireq = inet_rsk(req);
 
 	if (sk_acceptq_is_full(sk))
 		goto out_overflow;
@@ -1185,10 +1186,10 @@
 
 	memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 
-	newsk->sk_v6_daddr = treq->rmt_addr;
-	newnp->saddr = treq->loc_addr;
-	newsk->sk_v6_rcv_saddr = treq->loc_addr;
-	newsk->sk_bound_dev_if = treq->iif;
+	newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr;
+	newnp->saddr = ireq->ir_v6_loc_addr;
+	newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr;
+	newsk->sk_bound_dev_if = ireq->ir_iif;
 
 	/* Now IPv6 options...
 
@@ -1203,11 +1204,11 @@
 
 	/* Clone pktoptions received with SYN */
 	newnp->pktoptions = NULL;
-	if (treq->pktopts != NULL) {
-		newnp->pktoptions = skb_clone(treq->pktopts,
+	if (ireq->pktopts != NULL) {
+		newnp->pktoptions = skb_clone(ireq->pktopts,
 					      sk_gfp_atomic(sk, GFP_ATOMIC));
-		consume_skb(treq->pktopts);
-		treq->pktopts = NULL;
+		consume_skb(ireq->pktopts);
+		ireq->pktopts = NULL;
 		if (newnp->pktoptions)
 			skb_set_owner_r(newnp->pktoptions, newsk);
 	}
@@ -1722,8 +1723,8 @@
 			 const struct sock *sk, struct request_sock *req, int i, kuid_t uid)
 {
 	int ttd = req->expires - jiffies;
-	const struct in6_addr *src = &inet6_rsk(req)->loc_addr;
-	const struct in6_addr *dest = &inet6_rsk(req)->rmt_addr;
+	const struct in6_addr *src = &inet_rsk(req)->ir_v6_loc_addr;
+	const struct in6_addr *dest = &inet_rsk(req)->ir_v6_rmt_addr;
 
 	if (ttd < 0)
 		ttd = 0;
@@ -1734,10 +1735,10 @@
 		   i,
 		   src->s6_addr32[0], src->s6_addr32[1],
 		   src->s6_addr32[2], src->s6_addr32[3],
-		   ntohs(inet_rsk(req)->loc_port),
+		   ntohs(inet_rsk(req)->ir_loc_port),
 		   dest->s6_addr32[0], dest->s6_addr32[1],
 		   dest->s6_addr32[2], dest->s6_addr32[3],
-		   ntohs(inet_rsk(req)->rmt_port),
+		   ntohs(inet_rsk(req)->ir_rmt_port),
 		   TCP_SYN_RECV,
 		   0,0, /* could print option size, but that is af dependent. */
 		   1,   /* timers active (only the expire timer) */