[linux-2.6-block.git] / net / lapb / lapb_timer.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *	LAPB release 002
 *
 *	This code REQUIRES 2.1.15 or higher/ NET3.038
 *
 *	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, send DM up to N2 times, then switch to
		 *	STATE_1 and send SABM(E).
		 */
		case LAPB_STATE_0:
			if (lapb->mode & LAPB_DCE &&
			    lapb->n2count != lapb->n2) {
				lapb->n2count++;
				lapb_send_control(lapb, LAPB_DM, LAPB_POLLOFF, LAPB_RESPONSE);
			} else {
				lapb->state = LAPB_STATE_1;
				lapb_establish_data_link(lapb);
			}
			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
ee5d8f4d	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4 LT	2	/*
	3	* LAPB release 002
	4	*
	5	* This code REQUIRES 2.1.15 or higher/ NET3.038
	6	*
1da177e4 LT	7	* History
	8	* LAPB 001 Jonathan Naylor Started Coding
	9	* LAPB 002 Jonathan Naylor New timer architecture.
	10	*/
	11
a508da6c JP	12	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
a508da6c JP	13
1da177e4 LT	14	#include <linux/errno.h>
	15	#include <linux/types.h>
	16	#include <linux/socket.h>
	17	#include <linux/in.h>
	18	#include <linux/kernel.h>
	19	#include <linux/jiffies.h>
	20	#include <linux/timer.h>
	21	#include <linux/string.h>
	22	#include <linux/sockios.h>
	23	#include <linux/net.h>
	24	#include <linux/inet.h>
	25	#include <linux/skbuff.h>
	26	#include <net/sock.h>
7c0f6ba6	27	#include <linux/uaccess.h>
1da177e4 LT	28	#include <linux/fcntl.h>
	29	#include <linux/mm.h>
	30	#include <linux/interrupt.h>
	31	#include <net/lapb.h>
	32
83a37b32 KC	33	static void lapb_t1timer_expiry(struct timer_list *);
83a37b32 KC	34	static void lapb_t2timer_expiry(struct timer_list *);
1da177e4 LT	35
	36	void lapb_start_t1timer(struct lapb_cb *lapb)
	37	{
	38	del_timer(&lapb->t1timer);
	39
841b86f3	40	lapb->t1timer.function = lapb_t1timer_expiry;
1da177e4 LT	41	lapb->t1timer.expires = jiffies + lapb->t1;
	42
	43	add_timer(&lapb->t1timer);
	44	}
	45
	46	void lapb_start_t2timer(struct lapb_cb *lapb)
	47	{
	48	del_timer(&lapb->t2timer);
	49
841b86f3	50	lapb->t2timer.function = lapb_t2timer_expiry;
1da177e4 LT	51	lapb->t2timer.expires = jiffies + lapb->t2;
	52
	53	add_timer(&lapb->t2timer);
	54	}
	55
	56	void lapb_stop_t1timer(struct lapb_cb *lapb)
	57	{
	58	del_timer(&lapb->t1timer);
	59	}
	60
	61	void lapb_stop_t2timer(struct lapb_cb *lapb)
	62	{
	63	del_timer(&lapb->t2timer);
	64	}
	65
	66	int lapb_t1timer_running(struct lapb_cb *lapb)
	67	{
	68	return timer_pending(&lapb->t1timer);
	69	}
	70
83a37b32	71	static void lapb_t2timer_expiry(struct timer_list *t)
1da177e4	72	{
83a37b32	73	struct lapb_cb *lapb = from_timer(lapb, t, t2timer);
1da177e4 LT	74
	75	if (lapb->condition & LAPB_ACK_PENDING_CONDITION) {
	76	lapb->condition &= ~LAPB_ACK_PENDING_CONDITION;
	77	lapb_timeout_response(lapb);
	78	}
	79	}
	80
83a37b32	81	static void lapb_t1timer_expiry(struct timer_list *t)
1da177e4	82	{
83a37b32	83	struct lapb_cb *lapb = from_timer(lapb, t, t1timer);
1da177e4 LT	84
	85	switch (lapb->state) {
	86
	87	/*
62480b99 MS	88	* If we are a DCE, send DM up to N2 times, then switch to
62480b99 MS	89	* STATE_1 and send SABM(E).
1da177e4 LT	90	*/
1da177e4 LT	91	case LAPB_STATE_0:
62480b99 MS	92	if (lapb->mode & LAPB_DCE &&
	93	lapb->n2count != lapb->n2) {
	94	lapb->n2count++;
1da177e4	95	lapb_send_control(lapb, LAPB_DM, LAPB_POLLOFF, LAPB_RESPONSE);
62480b99 MS	96	} else {
	97	lapb->state = LAPB_STATE_1;
	98	lapb_establish_data_link(lapb);
	99	}
1da177e4 LT	100	break;
	101
	102	/*
	103	* Awaiting connection state, send SABM(E), up to N2 times.
	104	*/
56d6c3d7	105	case LAPB_STATE_1:
1da177e4 LT	106	if (lapb->n2count == lapb->n2) {
	107	lapb_clear_queues(lapb);
	108	lapb->state = LAPB_STATE_0;
	109	lapb_disconnect_indication(lapb, LAPB_TIMEDOUT);
a508da6c	110	lapb_dbg(0, "(%p) S1 -> S0\n", lapb->dev);
1da177e4 LT	111	return;
	112	} else {
	113	lapb->n2count++;
	114	if (lapb->mode & LAPB_EXTENDED) {
a508da6c JP	115	lapb_dbg(1, "(%p) S1 TX SABME(1)\n",
a508da6c JP	116	lapb->dev);
1da177e4 LT	117	lapb_send_control(lapb, LAPB_SABME, LAPB_POLLON, LAPB_COMMAND);
1da177e4 LT	118	} else {
a508da6c JP	119	lapb_dbg(1, "(%p) S1 TX SABM(1)\n",
a508da6c JP	120	lapb->dev);
1da177e4 LT	121	lapb_send_control(lapb, LAPB_SABM, LAPB_POLLON, LAPB_COMMAND);
	122	}
	123	}
	124	break;
	125
	126	/*
	127	* Awaiting disconnection state, send DISC, up to N2 times.
	128	*/
	129	case LAPB_STATE_2:
	130	if (lapb->n2count == lapb->n2) {
	131	lapb_clear_queues(lapb);
	132	lapb->state = LAPB_STATE_0;
	133	lapb_disconnect_confirmation(lapb, LAPB_TIMEDOUT);
a508da6c	134	lapb_dbg(0, "(%p) S2 -> S0\n", lapb->dev);
1da177e4 LT	135	return;
	136	} else {
	137	lapb->n2count++;
a508da6c	138	lapb_dbg(1, "(%p) S2 TX DISC(1)\n", lapb->dev);
1da177e4 LT	139	lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
	140	}
	141	break;
	142
	143	/*
	144	* Data transfer state, restransmit I frames, up to N2 times.
	145	*/
	146	case LAPB_STATE_3:
	147	if (lapb->n2count == lapb->n2) {
	148	lapb_clear_queues(lapb);
	149	lapb->state = LAPB_STATE_0;
	150	lapb_stop_t2timer(lapb);
	151	lapb_disconnect_indication(lapb, LAPB_TIMEDOUT);
a508da6c	152	lapb_dbg(0, "(%p) S3 -> S0\n", lapb->dev);
1da177e4 LT	153	return;
	154	} else {
	155	lapb->n2count++;
	156	lapb_requeue_frames(lapb);
a224bd36	157	lapb_kick(lapb);
1da177e4 LT	158	}
	159	break;
	160
	161	/*
	162	* Frame reject state, restransmit FRMR frames, up to N2 times.
	163	*/
	164	case LAPB_STATE_4:
	165	if (lapb->n2count == lapb->n2) {
	166	lapb_clear_queues(lapb);
	167	lapb->state = LAPB_STATE_0;
	168	lapb_disconnect_indication(lapb, LAPB_TIMEDOUT);
a508da6c	169	lapb_dbg(0, "(%p) S4 -> S0\n", lapb->dev);
1da177e4 LT	170	return;
	171	} else {
	172	lapb->n2count++;
	173	lapb_transmit_frmr(lapb);
	174	}
	175	break;
	176	}
	177
	178	lapb_start_t1timer(lapb);
	179	}