26 static u32 tcp_clamp_rto_to_user_timeout(const struct sock *sk)  in tcp_clamp_rto_to_user_timeout()  argument
28 	struct inet_connection_sock *icsk = inet_csk(sk);  in tcp_clamp_rto_to_user_timeout()
32 	start_ts = tcp_sk(sk)->retrans_stamp;  in tcp_clamp_rto_to_user_timeout()
35 	elapsed = tcp_time_stamp(tcp_sk(sk)) - start_ts;  in tcp_clamp_rto_to_user_timeout()
43 u32 tcp_clamp_probe0_to_user_timeout(const struct sock *sk, u32 when)  in tcp_clamp_probe0_to_user_timeout()  argument
45 	struct inet_connection_sock *icsk = inet_csk(sk);  in tcp_clamp_probe0_to_user_timeout()
68 static void tcp_write_err(struct sock *sk)  in tcp_write_err()  argument
70 	sk->sk_err = sk->sk_err_soft ? : ETIMEDOUT;  in tcp_write_err()
71 	sk_error_report(sk);  in tcp_write_err()
73 	tcp_write_queue_purge(sk);  in tcp_write_err()
74 	tcp_done(sk);  in tcp_write_err()
75 	__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONTIMEOUT);  in tcp_write_err()
102 static int tcp_out_of_resources(struct sock *sk, bool do_reset)  in tcp_out_of_resources()  argument
104 	struct tcp_sock *tp = tcp_sk(sk);  in tcp_out_of_resources()
113 	if (sk->sk_err_soft)  in tcp_out_of_resources()
116 	if (tcp_check_oom(sk, shift)) {  in tcp_out_of_resources()
124 			tcp_send_active_reset(sk, GFP_ATOMIC);  in tcp_out_of_resources()
125 		tcp_done(sk);  in tcp_out_of_resources()
126 		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONMEMORY);  in tcp_out_of_resources()
130 	if (!check_net(sock_net(sk))) {  in tcp_out_of_resources()
132 		tcp_done(sk);  in tcp_out_of_resources()
144 static int tcp_orphan_retries(struct sock *sk, bool alive)  in tcp_orphan_retries()  argument
146 	int retries = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_orphan_retries); /* May be zero. */  in tcp_orphan_retries()
149 	if (sk->sk_err_soft && !alive)  in tcp_orphan_retries()
160 static void tcp_mtu_probing(struct inet_connection_sock *icsk, struct sock *sk)  in tcp_mtu_probing()  argument
162 	const struct net *net = sock_net(sk);  in tcp_mtu_probing()
173 		mss = tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_low) >> 1;  in tcp_mtu_probing()
177 		icsk->icsk_mtup.search_low = tcp_mss_to_mtu(sk, mss);  in tcp_mtu_probing()
179 	tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);  in tcp_mtu_probing()
182 static unsigned int tcp_model_timeout(struct sock *sk,  in tcp_model_timeout()  argument
209 static bool retransmits_timed_out(struct sock *sk,  in retransmits_timed_out()  argument
215 	if (!inet_csk(sk)->icsk_retransmits)  in retransmits_timed_out()
218 	start_ts = tcp_sk(sk)->retrans_stamp;  in retransmits_timed_out()
222 		if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV))  in retransmits_timed_out()
223 			rto_base = tcp_timeout_init(sk);  in retransmits_timed_out()
224 		timeout = tcp_model_timeout(sk, boundary, rto_base);  in retransmits_timed_out()
227 	return (s32)(tcp_time_stamp(tcp_sk(sk)) - start_ts - timeout) >= 0;  in retransmits_timed_out()
231 static int tcp_write_timeout(struct sock *sk)  in tcp_write_timeout()  argument
233 	struct inet_connection_sock *icsk = inet_csk(sk);  in tcp_write_timeout()
234 	struct tcp_sock *tp = tcp_sk(sk);  in tcp_write_timeout()
235 	struct net *net = sock_net(sk);  in tcp_write_timeout()
239 	if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {  in tcp_write_timeout()
241 			__dst_negative_advice(sk);  in tcp_write_timeout()
246 		if (retransmits_timed_out(sk, READ_ONCE(net->ipv4.sysctl_tcp_retries1), 0)) {  in tcp_write_timeout()
248 			tcp_mtu_probing(icsk, sk);  in tcp_write_timeout()
250 			__dst_negative_advice(sk);  in tcp_write_timeout()
254 		if (sock_flag(sk, SOCK_DEAD)) {  in tcp_write_timeout()
257 			retry_until = tcp_orphan_retries(sk, alive);  in tcp_write_timeout()
259 				!retransmits_timed_out(sk, retry_until, 0);  in tcp_write_timeout()
261 			if (tcp_out_of_resources(sk, do_reset))  in tcp_write_timeout()
266 		expired = retransmits_timed_out(sk, retry_until,  in tcp_write_timeout()
268 	tcp_fastopen_active_detect_blackhole(sk, expired);  in tcp_write_timeout()
271 		tcp_call_bpf_3arg(sk, BPF_SOCK_OPS_RTO_CB,  in tcp_write_timeout()
277 		tcp_write_err(sk);  in tcp_write_timeout()
281 	if (sk_rethink_txhash(sk)) {  in tcp_write_timeout()
283 		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPTIMEOUTREHASH);  in tcp_write_timeout()
290 void tcp_delack_timer_handler(struct sock *sk)  in tcp_delack_timer_handler()  argument
292 	struct inet_connection_sock *icsk = inet_csk(sk);  in tcp_delack_timer_handler()
294 	if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN)) ||  in tcp_delack_timer_handler()
299 		sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout);  in tcp_delack_timer_handler()
304 	if (inet_csk_ack_scheduled(sk)) {  in tcp_delack_timer_handler()
305 		if (!inet_csk_in_pingpong_mode(sk)) {  in tcp_delack_timer_handler()
312 			inet_csk_exit_pingpong_mode(sk);  in tcp_delack_timer_handler()
315 		tcp_mstamp_refresh(tcp_sk(sk));  in tcp_delack_timer_handler()
316 		tcp_send_ack(sk);  in tcp_delack_timer_handler()
317 		__NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKS);  in tcp_delack_timer_handler()
335 	struct sock *sk = &icsk->icsk_inet.sk;  in tcp_delack_timer()  local
337 	bh_lock_sock(sk);  in tcp_delack_timer()
338 	if (!sock_owned_by_user(sk)) {  in tcp_delack_timer()
339 		tcp_delack_timer_handler(sk);  in tcp_delack_timer()
341 		__NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOCKED);  in tcp_delack_timer()
343 		if (!test_and_set_bit(TCP_DELACK_TIMER_DEFERRED, &sk->sk_tsq_flags))  in tcp_delack_timer()
344 			sock_hold(sk);  in tcp_delack_timer()
346 	bh_unlock_sock(sk);  in tcp_delack_timer()
347 	sock_put(sk);  in tcp_delack_timer()
350 static void tcp_probe_timer(struct sock *sk)  in tcp_probe_timer()  argument
352 	struct inet_connection_sock *icsk = inet_csk(sk);  in tcp_probe_timer()
353 	struct sk_buff *skb = tcp_send_head(sk);  in tcp_probe_timer()
354 	struct tcp_sock *tp = tcp_sk(sk);  in tcp_probe_timer()
378 	max_probes = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_retries2);  in tcp_probe_timer()
379 	if (sock_flag(sk, SOCK_DEAD)) {  in tcp_probe_timer()
382 		max_probes = tcp_orphan_retries(sk, alive);  in tcp_probe_timer()
385 		if (tcp_out_of_resources(sk, true))  in tcp_probe_timer()
390 abort:		tcp_write_err(sk);  in tcp_probe_timer()
393 		tcp_send_probe0(sk);  in tcp_probe_timer()
401 static void tcp_fastopen_synack_timer(struct sock *sk, struct request_sock *req)  in tcp_fastopen_synack_timer()  argument
403 	struct inet_connection_sock *icsk = inet_csk(sk);  in tcp_fastopen_synack_timer()
404 	struct tcp_sock *tp = tcp_sk(sk);  in tcp_fastopen_synack_timer()
411 		READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_synack_retries) + 1;  in tcp_fastopen_synack_timer()
414 		tcp_write_err(sk);  in tcp_fastopen_synack_timer()
419 		tcp_enter_loss(sk);  in tcp_fastopen_synack_timer()
425 	inet_rtx_syn_ack(sk, req);  in tcp_fastopen_synack_timer()
430 	inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,  in tcp_fastopen_synack_timer()
446 void tcp_retransmit_timer(struct sock *sk)  in tcp_retransmit_timer()  argument
448 	struct tcp_sock *tp = tcp_sk(sk);  in tcp_retransmit_timer()
449 	struct net *net = sock_net(sk);  in tcp_retransmit_timer()
450 	struct inet_connection_sock *icsk = inet_csk(sk);  in tcp_retransmit_timer()
455 					lockdep_sock_is_held(sk));  in tcp_retransmit_timer()
457 		WARN_ON_ONCE(sk->sk_state != TCP_SYN_RECV &&  in tcp_retransmit_timer()
458 			     sk->sk_state != TCP_FIN_WAIT1);  in tcp_retransmit_timer()
459 		tcp_fastopen_synack_timer(sk, req);  in tcp_retransmit_timer()
469 	skb = tcp_rtx_queue_head(sk);  in tcp_retransmit_timer()
475 	if (!tp->snd_wnd && !sock_flag(sk, SOCK_DEAD) &&  in tcp_retransmit_timer()
476 	    !((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV))) {  in tcp_retransmit_timer()
482 		struct inet_sock *inet = inet_sk(sk);  in tcp_retransmit_timer()
483 		if (sk->sk_family == AF_INET) {  in tcp_retransmit_timer()
491 		else if (sk->sk_family == AF_INET6) {  in tcp_retransmit_timer()
493 					    &sk->sk_v6_daddr,  in tcp_retransmit_timer()
500 			tcp_write_err(sk);  in tcp_retransmit_timer()
503 		tcp_enter_loss(sk);  in tcp_retransmit_timer()
504 		tcp_retransmit_skb(sk, skb, 1);  in tcp_retransmit_timer()
505 		__sk_dst_reset(sk);  in tcp_retransmit_timer()
509 	__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPTIMEOUTS);  in tcp_retransmit_timer()
510 	if (tcp_write_timeout(sk))  in tcp_retransmit_timer()
531 			__NET_INC_STATS(sock_net(sk), mib_idx);  in tcp_retransmit_timer()
534 	tcp_enter_loss(sk);  in tcp_retransmit_timer()
537 	if (tcp_retransmit_skb(sk, tcp_rtx_queue_head(sk), 1) > 0) {  in tcp_retransmit_timer()
541 		inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,  in tcp_retransmit_timer()
574 	if (sk->sk_state == TCP_ESTABLISHED &&  in tcp_retransmit_timer()
584 	inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,  in tcp_retransmit_timer()
585 				  tcp_clamp_rto_to_user_timeout(sk), TCP_RTO_MAX);  in tcp_retransmit_timer()
586 	if (retransmits_timed_out(sk, READ_ONCE(net->ipv4.sysctl_tcp_retries1) + 1, 0))  in tcp_retransmit_timer()
587 		__sk_dst_reset(sk);  in tcp_retransmit_timer()
594 void tcp_write_timer_handler(struct sock *sk)  in tcp_write_timer_handler()  argument
596 	struct inet_connection_sock *icsk = inet_csk(sk);  in tcp_write_timer_handler()
599 	if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN)) ||  in tcp_write_timer_handler()
604 		sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout);  in tcp_write_timer_handler()
608 	tcp_mstamp_refresh(tcp_sk(sk));  in tcp_write_timer_handler()
613 		tcp_rack_reo_timeout(sk);  in tcp_write_timer_handler()
616 		tcp_send_loss_probe(sk);  in tcp_write_timer_handler()
620 		tcp_retransmit_timer(sk);  in tcp_write_timer_handler()
624 		tcp_probe_timer(sk);  in tcp_write_timer_handler()
633 	struct sock *sk = &icsk->icsk_inet.sk;  in tcp_write_timer()  local
635 	bh_lock_sock(sk);  in tcp_write_timer()
636 	if (!sock_owned_by_user(sk)) {  in tcp_write_timer()
637 		tcp_write_timer_handler(sk);  in tcp_write_timer()
640 		if (!test_and_set_bit(TCP_WRITE_TIMER_DEFERRED, &sk->sk_tsq_flags))  in tcp_write_timer()
641 			sock_hold(sk);  in tcp_write_timer()
643 	bh_unlock_sock(sk);  in tcp_write_timer()
644 	sock_put(sk);  in tcp_write_timer()
655 void tcp_set_keepalive(struct sock *sk, int val)  in tcp_set_keepalive()  argument
657 	if ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))  in tcp_set_keepalive()
660 	if (val && !sock_flag(sk, SOCK_KEEPOPEN))  in tcp_set_keepalive()
661 		inet_csk_reset_keepalive_timer(sk, keepalive_time_when(tcp_sk(sk)));  in tcp_set_keepalive()
663 		inet_csk_delete_keepalive_timer(sk);  in tcp_set_keepalive()
670 	struct sock *sk = from_timer(sk, t, sk_timer);  in tcp_keepalive_timer()  local
671 	struct inet_connection_sock *icsk = inet_csk(sk);  in tcp_keepalive_timer()
672 	struct tcp_sock *tp = tcp_sk(sk);  in tcp_keepalive_timer()
676 	bh_lock_sock(sk);  in tcp_keepalive_timer()
677 	if (sock_owned_by_user(sk)) {  in tcp_keepalive_timer()
679 		inet_csk_reset_keepalive_timer (sk, HZ/20);  in tcp_keepalive_timer()
683 	if (sk->sk_state == TCP_LISTEN) {  in tcp_keepalive_timer()
689 	if (sk->sk_state == TCP_FIN_WAIT2 && sock_flag(sk, SOCK_DEAD)) {  in tcp_keepalive_timer()
691 			const int tmo = tcp_fin_time(sk) - TCP_TIMEWAIT_LEN;  in tcp_keepalive_timer()
694 				tcp_time_wait(sk, TCP_FIN_WAIT2, tmo);  in tcp_keepalive_timer()
698 		tcp_send_active_reset(sk, GFP_ATOMIC);  in tcp_keepalive_timer()
702 	if (!sock_flag(sk, SOCK_KEEPOPEN) ||  in tcp_keepalive_timer()
703 	    ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)))  in tcp_keepalive_timer()
709 	if (tp->packets_out || !tcp_write_queue_empty(sk))  in tcp_keepalive_timer()
723 			tcp_send_active_reset(sk, GFP_ATOMIC);  in tcp_keepalive_timer()
724 			tcp_write_err(sk);  in tcp_keepalive_timer()
727 		if (tcp_write_wakeup(sk, LINUX_MIB_TCPKEEPALIVE) <= 0) {  in tcp_keepalive_timer()
742 	inet_csk_reset_keepalive_timer (sk, elapsed);  in tcp_keepalive_timer()
746 	tcp_done(sk);  in tcp_keepalive_timer()
749 	bh_unlock_sock(sk);  in tcp_keepalive_timer()
750 	sock_put(sk);  in tcp_keepalive_timer()
756 	struct sock *sk = (struct sock *)tp;  in tcp_compressed_ack_kick()  local
758 	bh_lock_sock(sk);  in tcp_compressed_ack_kick()
759 	if (!sock_owned_by_user(sk)) {  in tcp_compressed_ack_kick()
766 			tcp_send_ack(sk);  in tcp_compressed_ack_kick()
770 				      &sk->sk_tsq_flags))  in tcp_compressed_ack_kick()
771 			sock_hold(sk);  in tcp_compressed_ack_kick()
773 	bh_unlock_sock(sk);  in tcp_compressed_ack_kick()
775 	sock_put(sk);  in tcp_compressed_ack_kick()
780 void tcp_init_xmit_timers(struct sock *sk)  in tcp_init_xmit_timers()  argument
782 	inet_csk_init_xmit_timers(sk, &tcp_write_timer, &tcp_delack_timer,  in tcp_init_xmit_timers()
784 	hrtimer_init(&tcp_sk(sk)->pacing_timer, CLOCK_MONOTONIC,  in tcp_init_xmit_timers()
786 	tcp_sk(sk)->pacing_timer.function = tcp_pace_kick;  in tcp_init_xmit_timers()
788 	hrtimer_init(&tcp_sk(sk)->compressed_ack_timer, CLOCK_MONOTONIC,  in tcp_init_xmit_timers()
790 	tcp_sk(sk)->compressed_ack_timer.function = tcp_compressed_ack_kick;  in tcp_init_xmit_timers()