[mirror_ubuntu-focal-kernel.git] / net / lapb / lapb_timer.c

/*
 *	LAPB release 002
 *
 *	This code REQUIRES 2.1.15 or higher/ NET3.038
 *
 *	This module:
 *		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.
 *
 *	History
 *	LAPB 001	Jonathan Naylor	Started Coding
 *	LAPB 002	Jonathan Naylor	New timer architecture.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.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 <linux/inet.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>
#include <net/lapb.h>

static void lapb_t1timer_expiry(struct timer_list *);
static void lapb_t2timer_expiry(struct timer_list *);

void lapb_start_t1timer(struct lapb_cb *lapb)
{
	del_timer(&lapb->t1timer);

	lapb->t1timer.function = lapb_t1timer_expiry;
	lapb->t1timer.expires  = jiffies + lapb->t1;

	add_timer(&lapb->t1timer);
}

void lapb_start_t2timer(struct lapb_cb *lapb)
{
	del_timer(&lapb->t2timer);

	lapb->t2timer.function = lapb_t2timer_expiry;
	lapb->t2timer.expires  = jiffies + lapb->t2;

	add_timer(&lapb->t2timer);
}

void lapb_stop_t1timer(struct lapb_cb *lapb)
{
	del_timer(&lapb->t1timer);
}

void lapb_stop_t2timer(struct lapb_cb *lapb)
{
	del_timer(&lapb->t2timer);
}

int lapb_t1timer_running(struct lapb_cb *lapb)
{
	return timer_pending(&lapb->t1timer);
}

static void lapb_t2timer_expiry(struct timer_list *t)
{
	struct lapb_cb *lapb = from_timer(lapb, t, t2timer);

	if (lapb->condition & LAPB_ACK_PENDING_CONDITION) {
		lapb->condition &= ~LAPB_ACK_PENDING_CONDITION;
		lapb_timeout_response(lapb);
	}
}

static void lapb_t1timer_expiry(struct timer_list *t)
{
	struct lapb_cb *lapb = from_timer(lapb, t, t1timer);

	switch (lapb->state) {

		/*
		 *	If we are a DCE, keep going DM .. DM .. DM
		 */
		case LAPB_STATE_0:
			if (lapb->mode & LAPB_DCE)
				lapb_send_control(lapb, LAPB_DM, LAPB_POLLOFF, LAPB_RESPONSE);
			break;

		/*
		 *	Awaiting connection state, send SABM(E), up to N2 times.
		 */
		case LAPB_STATE_1:
			if (lapb->n2count == lapb->n2) {
				lapb_clear_queues(lapb);
				lapb->state = LAPB_STATE_0;
				lapb_disconnect_indication(lapb, LAPB_TIMEDOUT);
				lapb_dbg(0, "(%p) S1 -> S0\n", lapb->dev);
				return;
			} else {
				lapb->n2count++;
				if (lapb->mode & LAPB_EXTENDED) {
					lapb_dbg(1, "(%p) S1 TX SABME(1)\n",
						 lapb->dev);
					lapb_send_control(lapb, LAPB_SABME, LAPB_POLLON, LAPB_COMMAND);
				} else {
					lapb_dbg(1, "(%p) S1 TX SABM(1)\n",
						 lapb->dev);
					lapb_send_control(lapb, LAPB_SABM, LAPB_POLLON, LAPB_COMMAND);
				}
			}
			break;

		/*
		 *	Awaiting disconnection state, send DISC, up to N2 times.
		 */
		case LAPB_STATE_2:
			if (lapb->n2count == lapb->n2) {
				lapb_clear_queues(lapb);
				lapb->state = LAPB_STATE_0;
				lapb_disconnect_confirmation(lapb, LAPB_TIMEDOUT);
				lapb_dbg(0, "(%p) S2 -> S0\n", lapb->dev);
				return;
			} else {
				lapb->n2count++;
				lapb_dbg(1, "(%p) S2 TX DISC(1)\n", lapb->dev);
				lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
			}
			break;

		/*
		 *	Data transfer state, restransmit I frames, up to N2 times.
		 */
		case LAPB_STATE_3:
			if (lapb->n2count == lapb->n2) {
				lapb_clear_queues(lapb);
				lapb->state = LAPB_STATE_0;
				lapb_stop_t2timer(lapb);
				lapb_disconnect_indication(lapb, LAPB_TIMEDOUT);
				lapb_dbg(0, "(%p) S3 -> S0\n", lapb->dev);
				return;
			} else {
				lapb->n2count++;
				lapb_requeue_frames(lapb);
				lapb_kick(lapb);
			}
			break;

		/*
		 *	Frame reject state, restransmit FRMR frames, up to N2 times.
		 */
		case LAPB_STATE_4:
			if (lapb->n2count == lapb->n2) {
				lapb_clear_queues(lapb);
				lapb->state = LAPB_STATE_0;
				lapb_disconnect_indication(lapb, LAPB_TIMEDOUT);
				lapb_dbg(0, "(%p) S4 -> S0\n", lapb->dev);
				return;
			} else {
				lapb->n2count++;
				lapb_transmit_frmr(lapb);
			}
			break;
	}

	lapb_start_t1timer(lapb);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* LAPB release 002
	3	*
	4	* This code REQUIRES 2.1.15 or higher/ NET3.038
	5	*
	6	* This module:
	7	* This module is free software; you can redistribute it and/or
	8	* modify it under the terms of the GNU General Public License
	9	* as published by the Free Software Foundation; either version
	10	* 2 of the License, or (at your option) any later version.
	11	*
	12	* History
	13	* LAPB 001 Jonathan Naylor Started Coding
	14	* LAPB 002 Jonathan Naylor New timer architecture.
	15	*/
	16
a508da6c JP	17	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
a508da6c JP	18
1da177e4 LT	19	#include <linux/errno.h>
	20	#include <linux/types.h>
	21	#include <linux/socket.h>
	22	#include <linux/in.h>
	23	#include <linux/kernel.h>
	24	#include <linux/jiffies.h>
	25	#include <linux/timer.h>
	26	#include <linux/string.h>
	27	#include <linux/sockios.h>
	28	#include <linux/net.h>
	29	#include <linux/inet.h>
	30	#include <linux/skbuff.h>
	31	#include <net/sock.h>
7c0f6ba6	32	#include <linux/uaccess.h>
1da177e4 LT	33	#include <linux/fcntl.h>
	34	#include <linux/mm.h>
	35	#include <linux/interrupt.h>
	36	#include <net/lapb.h>
	37
83a37b32 KC	38	static void lapb_t1timer_expiry(struct timer_list *);
83a37b32 KC	39	static void lapb_t2timer_expiry(struct timer_list *);
1da177e4 LT	40
	41	void lapb_start_t1timer(struct lapb_cb *lapb)
	42	{
	43	del_timer(&lapb->t1timer);
	44
841b86f3	45	lapb->t1timer.function = lapb_t1timer_expiry;
1da177e4 LT	46	lapb->t1timer.expires = jiffies + lapb->t1;
	47
	48	add_timer(&lapb->t1timer);
	49	}
	50
	51	void lapb_start_t2timer(struct lapb_cb *lapb)
	52	{
	53	del_timer(&lapb->t2timer);
	54
841b86f3	55	lapb->t2timer.function = lapb_t2timer_expiry;
1da177e4 LT	56	lapb->t2timer.expires = jiffies + lapb->t2;
	57
	58	add_timer(&lapb->t2timer);
	59	}
	60
	61	void lapb_stop_t1timer(struct lapb_cb *lapb)
	62	{
	63	del_timer(&lapb->t1timer);
	64	}
	65
	66	void lapb_stop_t2timer(struct lapb_cb *lapb)
	67	{
	68	del_timer(&lapb->t2timer);
	69	}
	70
	71	int lapb_t1timer_running(struct lapb_cb *lapb)
	72	{
	73	return timer_pending(&lapb->t1timer);
	74	}
	75
83a37b32	76	static void lapb_t2timer_expiry(struct timer_list *t)
1da177e4	77	{
83a37b32	78	struct lapb_cb *lapb = from_timer(lapb, t, t2timer);
1da177e4 LT	79
	80	if (lapb->condition & LAPB_ACK_PENDING_CONDITION) {
	81	lapb->condition &= ~LAPB_ACK_PENDING_CONDITION;
	82	lapb_timeout_response(lapb);
	83	}
	84	}
	85
83a37b32	86	static void lapb_t1timer_expiry(struct timer_list *t)
1da177e4	87	{
83a37b32	88	struct lapb_cb *lapb = from_timer(lapb, t, t1timer);
1da177e4 LT	89
	90	switch (lapb->state) {
	91
	92	/*
	93	* If we are a DCE, keep going DM .. DM .. DM
	94	*/
	95	case LAPB_STATE_0:
	96	if (lapb->mode & LAPB_DCE)
	97	lapb_send_control(lapb, LAPB_DM, LAPB_POLLOFF, LAPB_RESPONSE);
	98	break;
	99
	100	/*
	101	* Awaiting connection state, send SABM(E), up to N2 times.
	102	*/
56d6c3d7	103	case LAPB_STATE_1:
1da177e4 LT	104	if (lapb->n2count == lapb->n2) {
	105	lapb_clear_queues(lapb);
	106	lapb->state = LAPB_STATE_0;
	107	lapb_disconnect_indication(lapb, LAPB_TIMEDOUT);
a508da6c	108	lapb_dbg(0, "(%p) S1 -> S0\n", lapb->dev);
1da177e4 LT	109	return;
	110	} else {
	111	lapb->n2count++;
	112	if (lapb->mode & LAPB_EXTENDED) {
a508da6c JP	113	lapb_dbg(1, "(%p) S1 TX SABME(1)\n",
a508da6c JP	114	lapb->dev);
1da177e4 LT	115	lapb_send_control(lapb, LAPB_SABME, LAPB_POLLON, LAPB_COMMAND);
1da177e4 LT	116	} else {
a508da6c JP	117	lapb_dbg(1, "(%p) S1 TX SABM(1)\n",
a508da6c JP	118	lapb->dev);
1da177e4 LT	119	lapb_send_control(lapb, LAPB_SABM, LAPB_POLLON, LAPB_COMMAND);
	120	}
	121	}
	122	break;
	123
	124	/*
	125	* Awaiting disconnection state, send DISC, up to N2 times.
	126	*/
	127	case LAPB_STATE_2:
	128	if (lapb->n2count == lapb->n2) {
	129	lapb_clear_queues(lapb);
	130	lapb->state = LAPB_STATE_0;
	131	lapb_disconnect_confirmation(lapb, LAPB_TIMEDOUT);
a508da6c	132	lapb_dbg(0, "(%p) S2 -> S0\n", lapb->dev);
1da177e4 LT	133	return;
	134	} else {
	135	lapb->n2count++;
a508da6c	136	lapb_dbg(1, "(%p) S2 TX DISC(1)\n", lapb->dev);
1da177e4 LT	137	lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
	138	}
	139	break;
	140
	141	/*
	142	* Data transfer state, restransmit I frames, up to N2 times.
	143	*/
	144	case LAPB_STATE_3:
	145	if (lapb->n2count == lapb->n2) {
	146	lapb_clear_queues(lapb);
	147	lapb->state = LAPB_STATE_0;
	148	lapb_stop_t2timer(lapb);
	149	lapb_disconnect_indication(lapb, LAPB_TIMEDOUT);
a508da6c	150	lapb_dbg(0, "(%p) S3 -> S0\n", lapb->dev);
1da177e4 LT	151	return;
	152	} else {
	153	lapb->n2count++;
	154	lapb_requeue_frames(lapb);
a224bd36	155	lapb_kick(lapb);
1da177e4 LT	156	}
	157	break;
	158
	159	/*
	160	* Frame reject state, restransmit FRMR frames, up to N2 times.
	161	*/
	162	case LAPB_STATE_4:
	163	if (lapb->n2count == lapb->n2) {
	164	lapb_clear_queues(lapb);
	165	lapb->state = LAPB_STATE_0;
	166	lapb_disconnect_indication(lapb, LAPB_TIMEDOUT);
a508da6c	167	lapb_dbg(0, "(%p) S4 -> S0\n", lapb->dev);
1da177e4 LT	168	return;
	169	} else {
	170	lapb->n2count++;
	171	lapb_transmit_frmr(lapb);
	172	}
	173	break;
	174	}
	175
	176	lapb_start_t1timer(lapb);
	177	}