linux-stable/net/ax25/ax25_ds_timer.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program 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 3029 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/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

235 lines
5.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
*
* Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
* Copyright (C) Joerg Reuter DL1BKE (jreuter@yaina.de)
*/
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/spinlock.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/jiffies.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <net/tcp_states.h>
#include <net/ax25.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/uaccess.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
static void ax25_ds_timeout(struct timer_list *);
/*
* Add DAMA slave timeout timer to timer list.
* Unlike the connection based timers the timeout function gets
* triggered every second. Please note that NET_AX25_DAMA_SLAVE_TIMEOUT
* (aka /proc/sys/net/ax25/{dev}/dama_slave_timeout) is still in
* 1/10th of a second.
*/
void ax25_ds_setup_timer(ax25_dev *ax25_dev)
{
timer_setup(&ax25_dev->dama.slave_timer, ax25_ds_timeout, 0);
}
void ax25_ds_del_timer(ax25_dev *ax25_dev)
{
if (ax25_dev)
del_timer(&ax25_dev->dama.slave_timer);
}
void ax25_ds_set_timer(ax25_dev *ax25_dev)
{
if (ax25_dev == NULL) /* paranoia */
return;
ax25_dev->dama.slave_timeout =
msecs_to_jiffies(ax25_dev->values[AX25_VALUES_DS_TIMEOUT]) / 10;
mod_timer(&ax25_dev->dama.slave_timer, jiffies + HZ);
}
/*
* DAMA Slave Timeout
* Silently discard all (slave) connections in case our master forgot us...
*/
static void ax25_ds_timeout(struct timer_list *t)
{
ax25_dev *ax25_dev = from_timer(ax25_dev, t, dama.slave_timer);
ax25_cb *ax25;
if (ax25_dev == NULL || !ax25_dev->dama.slave)
return; /* Yikes! */
if (!ax25_dev->dama.slave_timeout || --ax25_dev->dama.slave_timeout) {
ax25_ds_set_timer(ax25_dev);
return;
}
spin_lock(&ax25_list_lock);
ax25_for_each(ax25, &ax25_list) {
if (ax25->ax25_dev != ax25_dev || !(ax25->condition & AX25_COND_DAMA_MODE))
continue;
ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
ax25_disconnect(ax25, ETIMEDOUT);
}
spin_unlock(&ax25_list_lock);
ax25_dev_dama_off(ax25_dev);
}
void ax25_ds_heartbeat_expiry(ax25_cb *ax25)
{
struct sock *sk=ax25->sk;
if (sk)
bh_lock_sock(sk);
switch (ax25->state) {
case AX25_STATE_0:
case AX25_STATE_2:
/* Magic here: If we listen() and a new link dies before it
is accepted() it isn't 'dead' so doesn't get removed. */
if (!sk || sock_flag(sk, SOCK_DESTROY) ||
(sk->sk_state == TCP_LISTEN &&
sock_flag(sk, SOCK_DEAD))) {
if (sk) {
sock_hold(sk);
ax25_destroy_socket(ax25);
bh_unlock_sock(sk);
/* Ungrab socket and destroy it */
sock_put(sk);
} else
ax25_destroy_socket(ax25);
return;
}
break;
case AX25_STATE_3:
/*
* Check the state of the receive buffer.
*/
if (sk != NULL) {
if (atomic_read(&sk->sk_rmem_alloc) <
(sk->sk_rcvbuf >> 1) &&
(ax25->condition & AX25_COND_OWN_RX_BUSY)) {
ax25->condition &= ~AX25_COND_OWN_RX_BUSY;
ax25->condition &= ~AX25_COND_ACK_PENDING;
break;
}
}
break;
}
if (sk)
bh_unlock_sock(sk);
ax25_start_heartbeat(ax25);
}
/* dl1bke 960114: T3 works much like the IDLE timeout, but
* gets reloaded with every frame for this
* connection.
*/
void ax25_ds_t3timer_expiry(ax25_cb *ax25)
{
ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
ax25_dama_off(ax25);
ax25_disconnect(ax25, ETIMEDOUT);
}
/* dl1bke 960228: close the connection when IDLE expires.
* unlike T3 this timer gets reloaded only on
* I frames.
*/
void ax25_ds_idletimer_expiry(ax25_cb *ax25)
{
ax25_clear_queues(ax25);
ax25->n2count = 0;
ax25->state = AX25_STATE_2;
ax25_calculate_t1(ax25);
ax25_start_t1timer(ax25);
ax25_stop_t3timer(ax25);
if (ax25->sk != NULL) {
bh_lock_sock(ax25->sk);
ax25->sk->sk_state = TCP_CLOSE;
ax25->sk->sk_err = 0;
ax25->sk->sk_shutdown |= SEND_SHUTDOWN;
if (!sock_flag(ax25->sk, SOCK_DEAD)) {
ax25->sk->sk_state_change(ax25->sk);
sock_set_flag(ax25->sk, SOCK_DEAD);
}
bh_unlock_sock(ax25->sk);
}
}
/* dl1bke 960114: The DAMA protocol requires to send data and SABM/DISC
* within the poll of any connected channel. Remember
* that we are not allowed to send anything unless we
* get polled by the Master.
*
* Thus we'll have to do parts of our T1 handling in
* ax25_enquiry_response().
*/
void ax25_ds_t1_timeout(ax25_cb *ax25)
{
switch (ax25->state) {
case AX25_STATE_1:
if (ax25->n2count == ax25->n2) {
if (ax25->modulus == AX25_MODULUS) {
ax25_disconnect(ax25, ETIMEDOUT);
return;
} else {
ax25->modulus = AX25_MODULUS;
ax25->window = ax25->ax25_dev->values[AX25_VALUES_WINDOW];
ax25->n2count = 0;
ax25_send_control(ax25, AX25_SABM, AX25_POLLOFF, AX25_COMMAND);
}
} else {
ax25->n2count++;
if (ax25->modulus == AX25_MODULUS)
ax25_send_control(ax25, AX25_SABM, AX25_POLLOFF, AX25_COMMAND);
else
ax25_send_control(ax25, AX25_SABME, AX25_POLLOFF, AX25_COMMAND);
}
break;
case AX25_STATE_2:
if (ax25->n2count == ax25->n2) {
ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
if (!sock_flag(ax25->sk, SOCK_DESTROY))
ax25_disconnect(ax25, ETIMEDOUT);
return;
} else {
ax25->n2count++;
}
break;
case AX25_STATE_3:
if (ax25->n2count == ax25->n2) {
ax25_send_control(ax25, AX25_DM, AX25_POLLON, AX25_RESPONSE);
ax25_disconnect(ax25, ETIMEDOUT);
return;
} else {
ax25->n2count++;
}
break;
}
ax25_calculate_t1(ax25);
ax25_start_t1timer(ax25);
}