tcp: Clean up some functions.

This patch adds no functional change and cleans up some functions
that the following patches touch around so that we make them tidy
and easy to review/revert.  The changes are

  - Keep reverse christmas tree order
  - Remove unnecessary init of port in inet_csk_find_open_port()
  - Use req_to_sk() once in reqsk_queue_unlink()
  - Use sock_net(sk) once in tcp_time_wait() and tcp_v[46]_connect()

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/ipv4/inet_connection_sock.c

@@ -286,15 +286,13 @@ inet_csk_find_open_port(const struct sock *sk, struct inet_bind_bucket **tb_ret,
 			struct inet_bind_hashbucket **head2_ret, int *port_ret)
 {
 	struct inet_hashinfo *hinfo = sk->sk_prot->h.hashinfo;
-	int port = 0;
+	int i, low, high, attempt_half, port, l3mdev;
 	struct inet_bind_hashbucket *head, *head2;
 	struct net *net = sock_net(sk);
-	bool relax = false;
-	int i, low, high, attempt_half;
 	struct inet_bind2_bucket *tb2;
 	struct inet_bind_bucket *tb;
 	u32 remaining, offset;
-	int l3mdev;
+	bool relax = false;
 
 	l3mdev = inet_sk_bound_l3mdev(sk);
 ports_exhausted:
@@ -471,15 +469,14 @@ int inet_csk_get_port(struct sock *sk, unsigned short snum)
 {
 	bool reuse = sk->sk_reuse && sk->sk_state != TCP_LISTEN;
 	struct inet_hashinfo *hinfo = sk->sk_prot->h.hashinfo;
-	int ret = 1, port = snum;
-	struct net *net = sock_net(sk);
 	bool found_port = false, check_bind_conflict = true;
 	bool bhash_created = false, bhash2_created = false;
 	struct inet_bind_hashbucket *head, *head2;
 	struct inet_bind2_bucket *tb2 = NULL;
 	struct inet_bind_bucket *tb = NULL;
 	bool head2_lock_acquired = false;
-	int l3mdev;
+	int ret = 1, port = snum, l3mdev;
+	struct net *net = sock_net(sk);
 
 	l3mdev = inet_sk_bound_l3mdev(sk);
 
@@ -909,14 +906,16 @@ static void reqsk_migrate_reset(struct request_sock *req)
 /* return true if req was found in the ehash table */
 static bool reqsk_queue_unlink(struct request_sock *req)
 {
-	struct inet_hashinfo *hashinfo = req_to_sk(req)->sk_prot->h.hashinfo;
+	struct sock *sk = req_to_sk(req);
 	bool found = false;
 
-	if (sk_hashed(req_to_sk(req))) {
-		spinlock_t *lock = inet_ehash_lockp(hashinfo, req->rsk_hash);
+	if (sk_hashed(sk)) {
+		struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
+		spinlock_t *lock;
 
+		lock = inet_ehash_lockp(hashinfo, req->rsk_hash);
 		spin_lock(lock);
-		found = __sk_nulls_del_node_init_rcu(req_to_sk(req));
+		found = __sk_nulls_del_node_init_rcu(sk);
 		spin_unlock(lock);
 	}
 	if (timer_pending(&req->rsk_timer) && del_timer_sync(&req->rsk_timer))

net/ipv4/inet_hashtables.c

@@ -169,13 +169,14 @@ void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb,
 static void __inet_put_port(struct sock *sk)
 {
 	struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
-	const int bhash = inet_bhashfn(sock_net(sk), inet_sk(sk)->inet_num,
-			hashinfo->bhash_size);
-	struct inet_bind_hashbucket *head = &hashinfo->bhash[bhash];
-	struct inet_bind_hashbucket *head2 =
-		inet_bhashfn_portaddr(hashinfo, sk, sock_net(sk),
-				      inet_sk(sk)->inet_num);
+	struct inet_bind_hashbucket *head, *head2;
+	struct net *net = sock_net(sk);
 	struct inet_bind_bucket *tb;
+	int bhash;
+
+	bhash = inet_bhashfn(net, inet_sk(sk)->inet_num, hashinfo->bhash_size);
+	head = &hashinfo->bhash[bhash];
+	head2 = inet_bhashfn_portaddr(hashinfo, sk, net, inet_sk(sk)->inet_num);
 
 	spin_lock(&head->lock);
 	tb = inet_csk(sk)->icsk_bind_hash;
@@ -209,17 +210,17 @@ int __inet_inherit_port(const struct sock *sk, struct sock *child)
 {
 	struct inet_hashinfo *table = sk->sk_prot->h.hashinfo;
 	unsigned short port = inet_sk(child)->inet_num;
-	const int bhash = inet_bhashfn(sock_net(sk), port,
-			table->bhash_size);
-	struct inet_bind_hashbucket *head = &table->bhash[bhash];
-	struct inet_bind_hashbucket *head2 =
-		inet_bhashfn_portaddr(table, child, sock_net(sk), port);
+	struct inet_bind_hashbucket *head, *head2;
 	bool created_inet_bind_bucket = false;
-	bool update_fastreuse = false;
 	struct net *net = sock_net(sk);
+	bool update_fastreuse = false;
 	struct inet_bind2_bucket *tb2;
 	struct inet_bind_bucket *tb;
-	int l3mdev;
+	int bhash, l3mdev;
+
+	bhash = inet_bhashfn(net, port, table->bhash_size);
+	head = &table->bhash[bhash];
+	head2 = inet_bhashfn_portaddr(table, child, net, port);
 
 	spin_lock(&head->lock);
 	spin_lock(&head2->lock);
@@ -629,8 +630,8 @@ static bool inet_ehash_lookup_by_sk(struct sock *sk,
 bool inet_ehash_insert(struct sock *sk, struct sock *osk, bool *found_dup_sk)
 {
 	struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
-	struct hlist_nulls_head *list;
 	struct inet_ehash_bucket *head;
+	struct hlist_nulls_head *list;
 	spinlock_t *lock;
 	bool ret = true;
 

net/ipv4/tcp_ipv4.c

@@ -201,15 +201,16 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 {
 	struct inet_bind_hashbucket *prev_addr_hashbucket = NULL;
 	struct sockaddr_in *usin = (struct sockaddr_in *)uaddr;
+	struct inet_timewait_death_row *tcp_death_row;
 	__be32 daddr, nexthop, prev_sk_rcv_saddr;
 	struct inet_sock *inet = inet_sk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
+	struct ip_options_rcu *inet_opt;
+	struct net *net = sock_net(sk);
 	__be16 orig_sport, orig_dport;
 	struct flowi4 *fl4;
 	struct rtable *rt;
 	int err;
-	struct ip_options_rcu *inet_opt;
-	struct inet_timewait_death_row *tcp_death_row = sock_net(sk)->ipv4.tcp_death_row;
 
 	if (addr_len < sizeof(struct sockaddr_in))
 		return -EINVAL;
@@ -235,7 +236,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	if (IS_ERR(rt)) {
 		err = PTR_ERR(rt);
 		if (err == -ENETUNREACH)
-			IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
+			IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
 		return err;
 	}
 
@@ -250,8 +251,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	if (!inet->inet_saddr) {
 		if (inet_csk(sk)->icsk_bind2_hash) {
 			prev_addr_hashbucket = inet_bhashfn_portaddr(&tcp_hashinfo,
-								     sk, sock_net(sk),
-								     inet->inet_num);
+								     sk, net, inet->inet_num);
 			prev_sk_rcv_saddr = sk->sk_rcv_saddr;
 		}
 		inet->inet_saddr = fl4->saddr;
@@ -292,6 +292,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	 * complete initialization after this.
 	 */
 	tcp_set_state(sk, TCP_SYN_SENT);
+	tcp_death_row = net->ipv4.tcp_death_row;
 	err = inet_hash_connect(tcp_death_row, sk);
 	if (err)
 		goto failure;
@@ -317,8 +318,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 						  inet->inet_daddr,
 						  inet->inet_sport,
 						  usin->sin_port));
-		tp->tsoffset = secure_tcp_ts_off(sock_net(sk),
-						 inet->inet_saddr,
+		tp->tsoffset = secure_tcp_ts_off(net, inet->inet_saddr,
 						 inet->inet_daddr);
 	}
 
@@ -2406,9 +2406,9 @@ static void *established_get_first(struct seq_file *seq)
 
 static void *established_get_next(struct seq_file *seq, void *cur)
 {
-	struct sock *sk = cur;
-	struct hlist_nulls_node *node;
 	struct tcp_iter_state *st = seq->private;
+	struct hlist_nulls_node *node;
+	struct sock *sk = cur;
 
 	++st->num;
 	++st->offset;

net/ipv4/tcp_minisocks.c

@@ -247,10 +247,10 @@ void tcp_time_wait(struct sock *sk, int state, int timeo)
 {
 	const struct inet_connection_sock *icsk = inet_csk(sk);
 	const struct tcp_sock *tp = tcp_sk(sk);
+	struct net *net = sock_net(sk);
 	struct inet_timewait_sock *tw;
-	struct inet_timewait_death_row *tcp_death_row = sock_net(sk)->ipv4.tcp_death_row;
 
-	tw = inet_twsk_alloc(sk, tcp_death_row, state);
+	tw = inet_twsk_alloc(sk, net->ipv4.tcp_death_row, state);
 
 	if (tw) {
 		struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw);
@@ -326,7 +326,7 @@ void tcp_time_wait(struct sock *sk, int state, int timeo)
 		 * socket up.  We've got bigger problems than
 		 * non-graceful socket closings.
 		 */
-		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPTIMEWAITOVERFLOW);
+		NET_INC_STATS(net, LINUX_MIB_TCPTIMEWAITOVERFLOW);
 	}
 
 	tcp_update_metrics(sk);

net/ipv6/tcp_ipv6.c

@@ -146,15 +146,16 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 			  int addr_len)
 {
 	struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
-	struct inet_sock *inet = inet_sk(sk);
 	struct inet_connection_sock *icsk = inet_csk(sk);
+	struct in6_addr *saddr = NULL, *final_p, final;
 	struct inet_timewait_death_row *tcp_death_row;
 	struct ipv6_pinfo *np = tcp_inet6_sk(sk);
+	struct inet_sock *inet = inet_sk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
-	struct in6_addr *saddr = NULL, *final_p, final;
+	struct net *net = sock_net(sk);
 	struct ipv6_txoptions *opt;
-	struct flowi6 fl6;
 	struct dst_entry *dst;
+	struct flowi6 fl6;
 	int addr_type;
 	int err;
 
@@ -280,7 +281,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 
 	security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
 
-	dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
+	dst = ip6_dst_lookup_flow(net, sk, &fl6, final_p);
 	if (IS_ERR(dst)) {
 		err = PTR_ERR(dst);
 		goto failure;
@@ -292,8 +293,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 
 		if (icsk->icsk_bind2_hash) {
 			prev_addr_hashbucket = inet_bhashfn_portaddr(&tcp_hashinfo,
-								     sk, sock_net(sk),
-								     inet->inet_num);
+								     sk, net, inet->inet_num);
 			prev_v6_rcv_saddr = sk->sk_v6_rcv_saddr;
 		}
 		saddr = &fl6.saddr;
@@ -325,7 +325,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 	inet->inet_dport = usin->sin6_port;
 
 	tcp_set_state(sk, TCP_SYN_SENT);
-	tcp_death_row = sock_net(sk)->ipv4.tcp_death_row;
+	tcp_death_row = net->ipv4.tcp_death_row;
 	err = inet6_hash_connect(tcp_death_row, sk);
 	if (err)
 		goto late_failure;
@@ -339,8 +339,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 						    sk->sk_v6_daddr.s6_addr32,
 						    inet->inet_sport,
 						    inet->inet_dport));
-		tp->tsoffset = secure_tcpv6_ts_off(sock_net(sk),
-						   np->saddr.s6_addr32,
+		tp->tsoffset = secure_tcpv6_ts_off(net, np->saddr.s6_addr32,
 						   sk->sk_v6_daddr.s6_addr32);
 	}