linux/net/x25/x25_timer.c
Thomas Gleixner ee5d8f4d89 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 41
Based on 1 normalized pattern(s):

  this module is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 18 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170858.008906948@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:12 +02:00

170 lines
3.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* X.25 Packet Layer release 002
*
* This is ALPHA test software. This code may break your machine,
* randomly fail to work with new releases, misbehave and/or generally
* screw up. It might even work.
*
* This code REQUIRES 2.1.15 or higher
*
* History
* X.25 001 Jonathan Naylor Started coding.
* X.25 002 Jonathan Naylor New timer architecture.
* Centralised disconnection processing.
*/
#include <linux/errno.h>
#include <linux/jiffies.h>
#include <linux/timer.h>
#include <net/sock.h>
#include <net/tcp_states.h>
#include <net/x25.h>
static void x25_heartbeat_expiry(struct timer_list *t);
static void x25_timer_expiry(struct timer_list *t);
void x25_init_timers(struct sock *sk)
{
struct x25_sock *x25 = x25_sk(sk);
timer_setup(&x25->timer, x25_timer_expiry, 0);
/* initialized by sock_init_data */
sk->sk_timer.function = x25_heartbeat_expiry;
}
void x25_start_heartbeat(struct sock *sk)
{
mod_timer(&sk->sk_timer, jiffies + 5 * HZ);
}
void x25_stop_heartbeat(struct sock *sk)
{
del_timer(&sk->sk_timer);
}
void x25_start_t2timer(struct sock *sk)
{
struct x25_sock *x25 = x25_sk(sk);
mod_timer(&x25->timer, jiffies + x25->t2);
}
void x25_start_t21timer(struct sock *sk)
{
struct x25_sock *x25 = x25_sk(sk);
mod_timer(&x25->timer, jiffies + x25->t21);
}
void x25_start_t22timer(struct sock *sk)
{
struct x25_sock *x25 = x25_sk(sk);
mod_timer(&x25->timer, jiffies + x25->t22);
}
void x25_start_t23timer(struct sock *sk)
{
struct x25_sock *x25 = x25_sk(sk);
mod_timer(&x25->timer, jiffies + x25->t23);
}
void x25_stop_timer(struct sock *sk)
{
del_timer(&x25_sk(sk)->timer);
}
unsigned long x25_display_timer(struct sock *sk)
{
struct x25_sock *x25 = x25_sk(sk);
if (!timer_pending(&x25->timer))
return 0;
return x25->timer.expires - jiffies;
}
static void x25_heartbeat_expiry(struct timer_list *t)
{
struct sock *sk = from_timer(sk, t, sk_timer);
bh_lock_sock(sk);
if (sock_owned_by_user(sk)) /* can currently only occur in state 3 */
goto restart_heartbeat;
switch (x25_sk(sk)->state) {
case X25_STATE_0:
/*
* Magic here: If we listen() and a new link dies
* before it is accepted() it isn't 'dead' so doesn't
* get removed.
*/
if (sock_flag(sk, SOCK_DESTROY) ||
(sk->sk_state == TCP_LISTEN &&
sock_flag(sk, SOCK_DEAD))) {
bh_unlock_sock(sk);
x25_destroy_socket_from_timer(sk);
return;
}
break;
case X25_STATE_3:
/*
* Check for the state of the receive buffer.
*/
x25_check_rbuf(sk);
break;
}
restart_heartbeat:
x25_start_heartbeat(sk);
bh_unlock_sock(sk);
}
/*
* Timer has expired, it may have been T2, T21, T22, or T23. We can tell
* by the state machine state.
*/
static inline void x25_do_timer_expiry(struct sock * sk)
{
struct x25_sock *x25 = x25_sk(sk);
switch (x25->state) {
case X25_STATE_3: /* T2 */
if (x25->condition & X25_COND_ACK_PENDING) {
x25->condition &= ~X25_COND_ACK_PENDING;
x25_enquiry_response(sk);
}
break;
case X25_STATE_1: /* T21 */
case X25_STATE_4: /* T22 */
x25_write_internal(sk, X25_CLEAR_REQUEST);
x25->state = X25_STATE_2;
x25_start_t23timer(sk);
break;
case X25_STATE_2: /* T23 */
x25_disconnect(sk, ETIMEDOUT, 0, 0);
break;
}
}
static void x25_timer_expiry(struct timer_list *t)
{
struct x25_sock *x25 = from_timer(x25, t, timer);
struct sock *sk = &x25->sk;
bh_lock_sock(sk);
if (sock_owned_by_user(sk)) { /* can currently only occur in state 3 */
if (x25_sk(sk)->state == X25_STATE_3)
x25_start_t2timer(sk);
} else
x25_do_timer_expiry(sk);
bh_unlock_sock(sk);
}