Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  *  net/dccp/timer.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  *  An implementation of the DCCP protocol
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  *  Arnaldo Carvalho de Melo <acme@conectiva.com.br>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) #include <linux/dccp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) #include <linux/skbuff.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) #include <linux/export.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include "dccp.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) /* sysctl variables governing numbers of retransmission attempts */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) int  sysctl_dccp_request_retries	__read_mostly = TCP_SYN_RETRIES;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) int  sysctl_dccp_retries1		__read_mostly = TCP_RETR1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) int  sysctl_dccp_retries2		__read_mostly = TCP_RETR2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) static void dccp_write_err(struct sock *sk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) 	sk->sk_err = sk->sk_err_soft ? : ETIMEDOUT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) 	sk->sk_error_report(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) 	dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) 	dccp_done(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) 	__DCCP_INC_STATS(DCCP_MIB_ABORTONTIMEOUT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) /* A write timeout has occurred. Process the after effects. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) static int dccp_write_timeout(struct sock *sk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 	const struct inet_connection_sock *icsk = inet_csk(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 	int retry_until;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 	if (sk->sk_state == DCCP_REQUESTING || sk->sk_state == DCCP_PARTOPEN) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 		if (icsk->icsk_retransmits != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 			dst_negative_advice(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 		retry_until = icsk->icsk_syn_retries ?
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 			    : sysctl_dccp_request_retries;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 		if (icsk->icsk_retransmits >= sysctl_dccp_retries1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 			/* NOTE. draft-ietf-tcpimpl-pmtud-01.txt requires pmtu
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 			   black hole detection. :-(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 			   It is place to make it. It is not made. I do not want
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 			   to make it. It is disguisting. It does not work in any
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 			   case. Let me to cite the same draft, which requires for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 			   us to implement this:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51)    "The one security concern raised by this memo is that ICMP black holes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52)    are often caused by over-zealous security administrators who block
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53)    all ICMP messages.  It is vitally important that those who design and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54)    deploy security systems understand the impact of strict filtering on
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55)    upper-layer protocols.  The safest web site in the world is worthless
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56)    if most TCP implementations cannot transfer data from it.  It would
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57)    be far nicer to have all of the black holes fixed rather than fixing
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58)    all of the TCP implementations."
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 			   Golden words :-).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 		   */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 			dst_negative_advice(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 		retry_until = sysctl_dccp_retries2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 		/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 		 * FIXME: see tcp_write_timout and tcp_out_of_resources
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 		 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 	if (icsk->icsk_retransmits >= retry_until) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 		/* Has it gone just too far? */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 		dccp_write_err(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 		return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81)  *	The DCCP retransmit timer.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) static void dccp_retransmit_timer(struct sock *sk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 	struct inet_connection_sock *icsk = inet_csk(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 	 * More than 4MSL (8 minutes) has passed, a RESET(aborted) was
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 	 * sent, no need to retransmit, this sock is dead.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 	if (dccp_write_timeout(sk))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 	 * We want to know the number of packets retransmitted, not the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 	 * total number of retransmissions of clones of original packets.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 	if (icsk->icsk_retransmits == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 		__DCCP_INC_STATS(DCCP_MIB_TIMEOUTS);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 	if (dccp_retransmit_skb(sk) != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 		/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 		 * Retransmission failed because of local congestion,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 		 * do not backoff.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 		 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 		if (--icsk->icsk_retransmits == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 			icsk->icsk_retransmits = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 		inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 					  min(icsk->icsk_rto,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 					      TCP_RESOURCE_PROBE_INTERVAL),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 					  DCCP_RTO_MAX);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 	icsk->icsk_backoff++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 	icsk->icsk_rto = min(icsk->icsk_rto << 1, DCCP_RTO_MAX);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 	inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, icsk->icsk_rto,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 				  DCCP_RTO_MAX);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 	if (icsk->icsk_retransmits > sysctl_dccp_retries1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 		__sk_dst_reset(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) static void dccp_write_timer(struct timer_list *t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 	struct inet_connection_sock *icsk =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 			from_timer(icsk, t, icsk_retransmit_timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 	struct sock *sk = &icsk->icsk_inet.sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 	int event = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	bh_lock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 	if (sock_owned_by_user(sk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 		/* Try again later */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 		sk_reset_timer(sk, &icsk->icsk_retransmit_timer,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 			       jiffies + (HZ / 20));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 	if (sk->sk_state == DCCP_CLOSED || !icsk->icsk_pending)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 	if (time_after(icsk->icsk_timeout, jiffies)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 		sk_reset_timer(sk, &icsk->icsk_retransmit_timer,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 			       icsk->icsk_timeout);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	event = icsk->icsk_pending;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 	icsk->icsk_pending = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 	switch (event) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 	case ICSK_TIME_RETRANS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 		dccp_retransmit_timer(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 	bh_unlock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 	sock_put(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) static void dccp_keepalive_timer(struct timer_list *t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 	struct sock *sk = from_timer(sk, t, sk_timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 	pr_err("dccp should not use a keepalive timer !\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 	sock_put(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) /* This is the same as tcp_delack_timer, sans prequeue & mem_reclaim stuff */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) static void dccp_delack_timer(struct timer_list *t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 	struct inet_connection_sock *icsk =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 			from_timer(icsk, t, icsk_delack_timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 	struct sock *sk = &icsk->icsk_inet.sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 	bh_lock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 	if (sock_owned_by_user(sk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 		/* Try again later. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 		__NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOCKED);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 		sk_reset_timer(sk, &icsk->icsk_delack_timer,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 			       jiffies + TCP_DELACK_MIN);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 	if (sk->sk_state == DCCP_CLOSED ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 	    !(icsk->icsk_ack.pending & ICSK_ACK_TIMER))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 	if (time_after(icsk->icsk_ack.timeout, jiffies)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 		sk_reset_timer(sk, &icsk->icsk_delack_timer,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 			       icsk->icsk_ack.timeout);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 	icsk->icsk_ack.pending &= ~ICSK_ACK_TIMER;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 	if (inet_csk_ack_scheduled(sk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) 		if (!inet_csk_in_pingpong_mode(sk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) 			/* Delayed ACK missed: inflate ATO. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 			icsk->icsk_ack.ato = min(icsk->icsk_ack.ato << 1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) 						 icsk->icsk_rto);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) 		} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) 			/* Delayed ACK missed: leave pingpong mode and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) 			 * deflate ATO.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) 			 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) 			inet_csk_exit_pingpong_mode(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) 			icsk->icsk_ack.ato = TCP_ATO_MIN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) 		dccp_send_ack(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) 		__NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKS);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) 	bh_unlock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) 	sock_put(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217)  * dccp_write_xmitlet  -  Workhorse for CCID packet dequeueing interface
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218)  * @data: Socket to act on
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220)  * See the comments above %ccid_dequeueing_decision for supported modes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) static void dccp_write_xmitlet(unsigned long data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) 	struct sock *sk = (struct sock *)data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) 	bh_lock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) 	if (sock_owned_by_user(sk))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) 		sk_reset_timer(sk, &dccp_sk(sk)->dccps_xmit_timer, jiffies + 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) 	else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) 		dccp_write_xmit(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) 	bh_unlock_sock(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) 	sock_put(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) static void dccp_write_xmit_timer(struct timer_list *t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) 	struct dccp_sock *dp = from_timer(dp, t, dccps_xmit_timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) 	struct sock *sk = &dp->dccps_inet_connection.icsk_inet.sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) 	dccp_write_xmitlet((unsigned long)sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) void dccp_init_xmit_timers(struct sock *sk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) 	struct dccp_sock *dp = dccp_sk(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) 	tasklet_init(&dp->dccps_xmitlet, dccp_write_xmitlet, (unsigned long)sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) 	timer_setup(&dp->dccps_xmit_timer, dccp_write_xmit_timer, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) 	inet_csk_init_xmit_timers(sk, &dccp_write_timer, &dccp_delack_timer,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) 				  &dccp_keepalive_timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) static ktime_t dccp_timestamp_seed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255)  * dccp_timestamp  -  10s of microseconds time source
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256)  * Returns the number of 10s of microseconds since loading DCCP. This is native
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257)  * DCCP time difference format (RFC 4340, sec. 13).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258)  * Please note: This will wrap around about circa every 11.9 hours.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) u32 dccp_timestamp(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) 	u64 delta = (u64)ktime_us_delta(ktime_get_real(), dccp_timestamp_seed);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) 	do_div(delta, 10);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) 	return delta;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) EXPORT_SYMBOL_GPL(dccp_timestamp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) void __init dccp_timestamping_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) 	dccp_timestamp_seed = ktime_get_real();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) }