[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, 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
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	/*
	88	* If we are a DCE, keep going DM .. DM .. DM
	89	*/
	90	case LAPB_STATE_0:
	91	if (lapb->mode & LAPB_DCE)
	92	lapb_send_control(lapb, LAPB_DM, LAPB_POLLOFF, LAPB_RESPONSE);
	93	break;
	94
	95	/*
	96	* Awaiting connection state, send SABM(E), up to N2 times.
	97	*/
56d6c3d7	98	case LAPB_STATE_1:
1da177e4 LT	99	if (lapb->n2count == lapb->n2) {
	100	lapb_clear_queues(lapb);
	101	lapb->state = LAPB_STATE_0;
	102	lapb_disconnect_indication(lapb, LAPB_TIMEDOUT);
a508da6c	103	lapb_dbg(0, "(%p) S1 -> S0\n", lapb->dev);
1da177e4 LT	104	return;
	105	} else {
	106	lapb->n2count++;
	107	if (lapb->mode & LAPB_EXTENDED) {
a508da6c JP	108	lapb_dbg(1, "(%p) S1 TX SABME(1)\n",
a508da6c JP	109	lapb->dev);
1da177e4 LT	110	lapb_send_control(lapb, LAPB_SABME, LAPB_POLLON, LAPB_COMMAND);
1da177e4 LT	111	} else {
a508da6c JP	112	lapb_dbg(1, "(%p) S1 TX SABM(1)\n",
a508da6c JP	113	lapb->dev);
1da177e4 LT	114	lapb_send_control(lapb, LAPB_SABM, LAPB_POLLON, LAPB_COMMAND);
	115	}
	116	}
	117	break;
	118
	119	/*
	120	* Awaiting disconnection state, send DISC, up to N2 times.
	121	*/
	122	case LAPB_STATE_2:
	123	if (lapb->n2count == lapb->n2) {
	124	lapb_clear_queues(lapb);
	125	lapb->state = LAPB_STATE_0;
	126	lapb_disconnect_confirmation(lapb, LAPB_TIMEDOUT);
a508da6c	127	lapb_dbg(0, "(%p) S2 -> S0\n", lapb->dev);
1da177e4 LT	128	return;
	129	} else {
	130	lapb->n2count++;
a508da6c	131	lapb_dbg(1, "(%p) S2 TX DISC(1)\n", lapb->dev);
1da177e4 LT	132	lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
	133	}
	134	break;
	135
	136	/*
	137	* Data transfer state, restransmit I frames, up to N2 times.
	138	*/
	139	case LAPB_STATE_3:
	140	if (lapb->n2count == lapb->n2) {
	141	lapb_clear_queues(lapb);
	142	lapb->state = LAPB_STATE_0;
	143	lapb_stop_t2timer(lapb);
	144	lapb_disconnect_indication(lapb, LAPB_TIMEDOUT);
a508da6c	145	lapb_dbg(0, "(%p) S3 -> S0\n", lapb->dev);
1da177e4 LT	146	return;
	147	} else {
	148	lapb->n2count++;
	149	lapb_requeue_frames(lapb);
a224bd36	150	lapb_kick(lapb);
1da177e4 LT	151	}
	152	break;
	153
	154	/*
	155	* Frame reject state, restransmit FRMR frames, up to N2 times.
	156	*/
	157	case LAPB_STATE_4:
	158	if (lapb->n2count == lapb->n2) {
	159	lapb_clear_queues(lapb);
	160	lapb->state = LAPB_STATE_0;
	161	lapb_disconnect_indication(lapb, LAPB_TIMEDOUT);
a508da6c	162	lapb_dbg(0, "(%p) S4 -> S0\n", lapb->dev);
1da177e4 LT	163	return;
	164	} else {
	165	lapb->n2count++;
	166	lapb_transmit_frmr(lapb);
	167	}
	168	break;
	169	}
	170
	171	lapb_start_t1timer(lapb);
	172	}