[deliverable/linux.git] / net / lapb / lapb_iface.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.
 *	2000-10-29	Henner Eisen	lapb_data_indication() return status.
 */

#include <linux/module.h>
#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/if_arp.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/stat.h>
#include <linux/init.h>
#include <net/lapb.h>

static LIST_HEAD(lapb_list);
static DEFINE_RWLOCK(lapb_list_lock);

/*
 *	Free an allocated lapb control block.
 */
static void lapb_free_cb(struct lapb_cb *lapb)
{
	kfree(lapb);
}

static __inline__ void lapb_hold(struct lapb_cb *lapb)
{
	atomic_inc(&lapb->refcnt);
}

static __inline__ void lapb_put(struct lapb_cb *lapb)
{
	if (atomic_dec_and_test(&lapb->refcnt))
		lapb_free_cb(lapb);
}

/*
 *	Socket removal during an interrupt is now safe.
 */
static void __lapb_remove_cb(struct lapb_cb *lapb)
{
	if (lapb->node.next) {
		list_del(&lapb->node);
		lapb_put(lapb);
	}
}

/*
 *	Add a socket to the bound sockets list.
 */
static void __lapb_insert_cb(struct lapb_cb *lapb)
{
	list_add(&lapb->node, &lapb_list);
	lapb_hold(lapb);
}

static struct lapb_cb *__lapb_devtostruct(struct net_device *dev)
{
	struct list_head *entry;
	struct lapb_cb *lapb, *use = NULL;

	list_for_each(entry, &lapb_list) {
		lapb = list_entry(entry, struct lapb_cb, node);
		if (lapb->dev == dev) {
			use = lapb;
			break;
		}
	}

	if (use)
		lapb_hold(use);

	return use;
}

static struct lapb_cb *lapb_devtostruct(struct net_device *dev)
{
	struct lapb_cb *rc;

	read_lock_bh(&lapb_list_lock);
	rc = __lapb_devtostruct(dev);
	read_unlock_bh(&lapb_list_lock);

	return rc;
}
/*
 *	Create an empty LAPB control block.
 */
static struct lapb_cb *lapb_create_cb(void)
{
	struct lapb_cb *lapb = kzalloc(sizeof(*lapb), GFP_ATOMIC);


	if (!lapb)
		goto out;

	skb_queue_head_init(&lapb->write_queue);
	skb_queue_head_init(&lapb->ack_queue);

	init_timer(&lapb->t1timer);
	init_timer(&lapb->t2timer);

	lapb->t1      = LAPB_DEFAULT_T1;
	lapb->t2      = LAPB_DEFAULT_T2;
	lapb->n2      = LAPB_DEFAULT_N2;
	lapb->mode    = LAPB_DEFAULT_MODE;
	lapb->window  = LAPB_DEFAULT_WINDOW;
	lapb->state   = LAPB_STATE_0;
	atomic_set(&lapb->refcnt, 1);
out:
	return lapb;
}

int lapb_register(struct net_device *dev,
		  const struct lapb_register_struct *callbacks)
{
	struct lapb_cb *lapb;
	int rc = LAPB_BADTOKEN;

	write_lock_bh(&lapb_list_lock);

	lapb = __lapb_devtostruct(dev);
	if (lapb) {
		lapb_put(lapb);
		goto out;
	}

	lapb = lapb_create_cb();
	rc = LAPB_NOMEM;
	if (!lapb)
		goto out;

	lapb->dev       = dev;
	lapb->callbacks = callbacks;

	__lapb_insert_cb(lapb);

	lapb_start_t1timer(lapb);

	rc = LAPB_OK;
out:
	write_unlock_bh(&lapb_list_lock);
	return rc;
}

int lapb_unregister(struct net_device *dev)
{
	struct lapb_cb *lapb;
	int rc = LAPB_BADTOKEN;

	write_lock_bh(&lapb_list_lock);
	lapb = __lapb_devtostruct(dev);
	if (!lapb)
		goto out;

	lapb_stop_t1timer(lapb);
	lapb_stop_t2timer(lapb);

	lapb_clear_queues(lapb);

	__lapb_remove_cb(lapb);

	lapb_put(lapb);
	rc = LAPB_OK;
out:
	write_unlock_bh(&lapb_list_lock);
	return rc;
}

int lapb_getparms(struct net_device *dev, struct lapb_parms_struct *parms)
{
	int rc = LAPB_BADTOKEN;
	struct lapb_cb *lapb = lapb_devtostruct(dev);

	if (!lapb)
		goto out;

	parms->t1      = lapb->t1 / HZ;
	parms->t2      = lapb->t2 / HZ;
	parms->n2      = lapb->n2;
	parms->n2count = lapb->n2count;
	parms->state   = lapb->state;
	parms->window  = lapb->window;
	parms->mode    = lapb->mode;

	if (!timer_pending(&lapb->t1timer))
		parms->t1timer = 0;
	else
		parms->t1timer = (lapb->t1timer.expires - jiffies) / HZ;

	if (!timer_pending(&lapb->t2timer))
		parms->t2timer = 0;
	else
		parms->t2timer = (lapb->t2timer.expires - jiffies) / HZ;

	lapb_put(lapb);
	rc = LAPB_OK;
out:
	return rc;
}

int lapb_setparms(struct net_device *dev, struct lapb_parms_struct *parms)
{
	int rc = LAPB_BADTOKEN;
	struct lapb_cb *lapb = lapb_devtostruct(dev);

	if (!lapb)
		goto out;

	rc = LAPB_INVALUE;
	if (parms->t1 < 1 || parms->t2 < 1 || parms->n2 < 1)
		goto out_put;

	if (lapb->state == LAPB_STATE_0) {
		if (parms->mode & LAPB_EXTENDED) {
			if (parms->window < 1 || parms->window > 127)
				goto out_put;
		} else {
			if (parms->window < 1 || parms->window > 7)
				goto out_put;
		}
		lapb->mode    = parms->mode;
		lapb->window  = parms->window;
	}

	lapb->t1    = parms->t1 * HZ;
	lapb->t2    = parms->t2 * HZ;
	lapb->n2    = parms->n2;

	rc = LAPB_OK;
out_put:
	lapb_put(lapb);
out:
	return rc;
}

int lapb_connect_request(struct net_device *dev)
{
	struct lapb_cb *lapb = lapb_devtostruct(dev);
	int rc = LAPB_BADTOKEN;

	if (!lapb)
		goto out;

	rc = LAPB_OK;
	if (lapb->state == LAPB_STATE_1)
		goto out_put;

	rc = LAPB_CONNECTED;
	if (lapb->state == LAPB_STATE_3 || lapb->state == LAPB_STATE_4)
		goto out_put;

	lapb_establish_data_link(lapb);

#if LAPB_DEBUG > 0
	printk(KERN_DEBUG "lapb: (%p) S0 -> S1\n", lapb->dev);
#endif
	lapb->state = LAPB_STATE_1;

	rc = LAPB_OK;
out_put:
	lapb_put(lapb);
out:
	return rc;
}

int lapb_disconnect_request(struct net_device *dev)
{
	struct lapb_cb *lapb = lapb_devtostruct(dev);
	int rc = LAPB_BADTOKEN;

	if (!lapb)
		goto out;

	switch (lapb->state) {
	case LAPB_STATE_0:
		rc = LAPB_NOTCONNECTED;
		goto out_put;

	case LAPB_STATE_1:
#if LAPB_DEBUG > 1
		printk(KERN_DEBUG "lapb: (%p) S1 TX DISC(1)\n", lapb->dev);
#endif
#if LAPB_DEBUG > 0
		printk(KERN_DEBUG "lapb: (%p) S1 -> S0\n", lapb->dev);
#endif
		lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
		lapb->state = LAPB_STATE_0;
		lapb_start_t1timer(lapb);
		rc = LAPB_NOTCONNECTED;
		goto out_put;

	case LAPB_STATE_2:
		rc = LAPB_OK;
		goto out_put;
	}

	lapb_clear_queues(lapb);
	lapb->n2count = 0;
	lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
	lapb_start_t1timer(lapb);
	lapb_stop_t2timer(lapb);
	lapb->state = LAPB_STATE_2;

#if LAPB_DEBUG > 1
	printk(KERN_DEBUG "lapb: (%p) S3 DISC(1)\n", lapb->dev);
#endif
#if LAPB_DEBUG > 0
	printk(KERN_DEBUG "lapb: (%p) S3 -> S2\n", lapb->dev);
#endif

	rc = LAPB_OK;
out_put:
	lapb_put(lapb);
out:
	return rc;
}

int lapb_data_request(struct net_device *dev, struct sk_buff *skb)
{
	struct lapb_cb *lapb = lapb_devtostruct(dev);
	int rc = LAPB_BADTOKEN;

	if (!lapb)
		goto out;

	rc = LAPB_NOTCONNECTED;
	if (lapb->state != LAPB_STATE_3 && lapb->state != LAPB_STATE_4)
		goto out_put;

	skb_queue_tail(&lapb->write_queue, skb);
	lapb_kick(lapb);
	rc = LAPB_OK;
out_put:
	lapb_put(lapb);
out:
	return rc;
}

int lapb_data_received(struct net_device *dev, struct sk_buff *skb)
{
	struct lapb_cb *lapb = lapb_devtostruct(dev);
	int rc = LAPB_BADTOKEN;

	if (lapb) {
		lapb_data_input(lapb, skb);
		lapb_put(lapb);
		rc = LAPB_OK;
	}

	return rc;
}

void lapb_connect_confirmation(struct lapb_cb *lapb, int reason)
{
	if (lapb->callbacks->connect_confirmation)
		lapb->callbacks->connect_confirmation(lapb->dev, reason);
}

void lapb_connect_indication(struct lapb_cb *lapb, int reason)
{
	if (lapb->callbacks->connect_indication)
		lapb->callbacks->connect_indication(lapb->dev, reason);
}

void lapb_disconnect_confirmation(struct lapb_cb *lapb, int reason)
{
	if (lapb->callbacks->disconnect_confirmation)
		lapb->callbacks->disconnect_confirmation(lapb->dev, reason);
}

void lapb_disconnect_indication(struct lapb_cb *lapb, int reason)
{
	if (lapb->callbacks->disconnect_indication)
		lapb->callbacks->disconnect_indication(lapb->dev, reason);
}

int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *skb)
{
	if (lapb->callbacks->data_indication)
		return lapb->callbacks->data_indication(lapb->dev, skb);

	kfree_skb(skb);
	return NET_RX_SUCCESS; /* For now; must be != NET_RX_DROP */
}

int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *skb)
{
	int used = 0;

	if (lapb->callbacks->data_transmit) {
		lapb->callbacks->data_transmit(lapb->dev, skb);
		used = 1;
	}

	return used;
}

EXPORT_SYMBOL(lapb_register);
EXPORT_SYMBOL(lapb_unregister);
EXPORT_SYMBOL(lapb_getparms);
EXPORT_SYMBOL(lapb_setparms);
EXPORT_SYMBOL(lapb_connect_request);
EXPORT_SYMBOL(lapb_disconnect_request);
EXPORT_SYMBOL(lapb_data_request);
EXPORT_SYMBOL(lapb_data_received);

static int __init lapb_init(void)
{
	return 0;
}

static void __exit lapb_exit(void)
{
	WARN_ON(!list_empty(&lapb_list));
}

MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
MODULE_DESCRIPTION("The X.25 Link Access Procedure B link layer protocol");
MODULE_LICENSE("GPL");

module_init(lapb_init);
module_exit(lapb_exit);
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	* 2000-10-29 Henner Eisen lapb_data_indication() return status.
	16	*/
56d6c3d7	17
1da177e4 LT	18	#include <linux/module.h>
	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/if_arp.h>
	31	#include <linux/skbuff.h>
5a0e3ad6	32	#include <linux/slab.h>
1da177e4 LT	33	#include <net/sock.h>
	34	#include <asm/uaccess.h>
	35	#include <asm/system.h>
	36	#include <linux/fcntl.h>
	37	#include <linux/mm.h>
	38	#include <linux/interrupt.h>
	39	#include <linux/stat.h>
	40	#include <linux/init.h>
	41	#include <net/lapb.h>
	42
14d0e7b7	43	static LIST_HEAD(lapb_list);
1da177e4 LT	44	static DEFINE_RWLOCK(lapb_list_lock);
	45
	46	/*
56d6c3d7	47	* Free an allocated lapb control block.
1da177e4 LT	48	*/
	49	static void lapb_free_cb(struct lapb_cb *lapb)
	50	{
	51	kfree(lapb);
	52	}
	53
	54	static __inline__ void lapb_hold(struct lapb_cb *lapb)
	55	{
	56	atomic_inc(&lapb->refcnt);
	57	}
	58
	59	static __inline__ void lapb_put(struct lapb_cb *lapb)
	60	{
	61	if (atomic_dec_and_test(&lapb->refcnt))
	62	lapb_free_cb(lapb);
	63	}
	64
	65	/*
	66	* Socket removal during an interrupt is now safe.
	67	*/
	68	static void __lapb_remove_cb(struct lapb_cb *lapb)
	69	{
	70	if (lapb->node.next) {
	71	list_del(&lapb->node);
	72	lapb_put(lapb);
	73	}
	74	}
	75
	76	/*
	77	* Add a socket to the bound sockets list.
	78	*/
	79	static void __lapb_insert_cb(struct lapb_cb *lapb)
	80	{
	81	list_add(&lapb->node, &lapb_list);
	82	lapb_hold(lapb);
	83	}
	84
	85	static struct lapb_cb __lapb_devtostruct(struct net_device dev)
	86	{
	87	struct list_head *entry;
	88	struct lapb_cb lapb, use = NULL;
	89
	90	list_for_each(entry, &lapb_list) {
	91	lapb = list_entry(entry, struct lapb_cb, node);
	92	if (lapb->dev == dev) {
	93	use = lapb;
	94	break;
	95	}
	96	}
	97
	98	if (use)
	99	lapb_hold(use);
	100
	101	return use;
	102	}
	103
	104	static struct lapb_cb lapb_devtostruct(struct net_device dev)
	105	{
	106	struct lapb_cb *rc;
	107
	108	read_lock_bh(&lapb_list_lock);
	109	rc = __lapb_devtostruct(dev);
	110	read_unlock_bh(&lapb_list_lock);
	111
112	return rc;
113	}
114	/*
115	* Create an empty LAPB control block.
116	*/
117	static struct lapb_cb *lapb_create_cb(void)
118	{
0da974f4	119	struct lapb_cb lapb = kzalloc(sizeof(lapb), GFP_ATOMIC);
1da177e4 LT	120
	121
	122	if (!lapb)
	123	goto out;
	124
1da177e4 LT	125	skb_queue_head_init(&lapb->write_queue);
	126	skb_queue_head_init(&lapb->ack_queue);
	127
	128	init_timer(&lapb->t1timer);
	129	init_timer(&lapb->t2timer);
	130
	131	lapb->t1 = LAPB_DEFAULT_T1;
	132	lapb->t2 = LAPB_DEFAULT_T2;
	133	lapb->n2 = LAPB_DEFAULT_N2;
	134	lapb->mode = LAPB_DEFAULT_MODE;
	135	lapb->window = LAPB_DEFAULT_WINDOW;
	136	lapb->state = LAPB_STATE_0;
	137	atomic_set(&lapb->refcnt, 1);
	138	out:
	139	return lapb;
	140	}
	141
d97a077a	142	int lapb_register(struct net_device *dev,
d97a077a	143	const struct lapb_register_struct *callbacks)
1da177e4 LT	144	{
	145	struct lapb_cb *lapb;
	146	int rc = LAPB_BADTOKEN;
	147
	148	write_lock_bh(&lapb_list_lock);
	149
	150	lapb = __lapb_devtostruct(dev);
	151	if (lapb) {
	152	lapb_put(lapb);
	153	goto out;
	154	}
	155
	156	lapb = lapb_create_cb();
	157	rc = LAPB_NOMEM;
	158	if (!lapb)
	159	goto out;
	160
	161	lapb->dev = dev;
d97a077a	162	lapb->callbacks = callbacks;
1da177e4 LT	163
	164	__lapb_insert_cb(lapb);
	165
	166	lapb_start_t1timer(lapb);
	167
	168	rc = LAPB_OK;
	169	out:
	170	write_unlock_bh(&lapb_list_lock);
	171	return rc;
	172	}
	173
	174	int lapb_unregister(struct net_device *dev)
	175	{
	176	struct lapb_cb *lapb;
	177	int rc = LAPB_BADTOKEN;
	178
	179	write_lock_bh(&lapb_list_lock);
	180	lapb = __lapb_devtostruct(dev);
	181	if (!lapb)
	182	goto out;
	183
	184	lapb_stop_t1timer(lapb);
	185	lapb_stop_t2timer(lapb);
	186
	187	lapb_clear_queues(lapb);
	188
	189	__lapb_remove_cb(lapb);
	190
	191	lapb_put(lapb);
	192	rc = LAPB_OK;
	193	out:
	194	write_unlock_bh(&lapb_list_lock);
	195	return rc;
	196	}
	197
	198	int lapb_getparms(struct net_device dev, struct lapb_parms_struct parms)
	199	{
	200	int rc = LAPB_BADTOKEN;
	201	struct lapb_cb *lapb = lapb_devtostruct(dev);
	202
	203	if (!lapb)
	204	goto out;
	205
	206	parms->t1 = lapb->t1 / HZ;
	207	parms->t2 = lapb->t2 / HZ;
	208	parms->n2 = lapb->n2;
	209	parms->n2count = lapb->n2count;
	210	parms->state = lapb->state;
	211	parms->window = lapb->window;
	212	parms->mode = lapb->mode;
	213
	214	if (!timer_pending(&lapb->t1timer))
	215	parms->t1timer = 0;
	216	else
	217	parms->t1timer = (lapb->t1timer.expires - jiffies) / HZ;
	218
	219	if (!timer_pending(&lapb->t2timer))
	220	parms->t2timer = 0;
	221	else
	222	parms->t2timer = (lapb->t2timer.expires - jiffies) / HZ;
	223
	224	lapb_put(lapb);
	225	rc = LAPB_OK;
	226	out:
227	return rc;
228	}
229
230	int lapb_setparms(struct net_device dev, struct lapb_parms_struct parms)
231	{
232	int rc = LAPB_BADTOKEN;
233	struct lapb_cb *lapb = lapb_devtostruct(dev);
234
235	if (!lapb)
236	goto out;
237
238	rc = LAPB_INVALUE;
239	if (parms->t1 < 1 \|\| parms->t2 < 1 \|\| parms->n2 < 1)
240	goto out_put;
241
242	if (lapb->state == LAPB_STATE_0) {
558e10a5 DC	243	if (parms->mode & LAPB_EXTENDED) {
	244	if (parms->window < 1 \|\| parms->window > 127)
	245	goto out_put;
	246	} else {
	247	if (parms->window < 1 \|\| parms->window > 7)
	248	goto out_put;
	249	}
1da177e4 LT	250	lapb->mode = parms->mode;
	251	lapb->window = parms->window;
	252	}
	253
	254	lapb->t1 = parms->t1 * HZ;
	255	lapb->t2 = parms->t2 * HZ;
	256	lapb->n2 = parms->n2;
	257
	258	rc = LAPB_OK;
	259	out_put:
	260	lapb_put(lapb);
	261	out:
	262	return rc;
	263	}
	264
	265	int lapb_connect_request(struct net_device *dev)
	266	{
	267	struct lapb_cb *lapb = lapb_devtostruct(dev);
	268	int rc = LAPB_BADTOKEN;
	269
	270	if (!lapb)
	271	goto out;
	272
	273	rc = LAPB_OK;
	274	if (lapb->state == LAPB_STATE_1)
	275	goto out_put;
	276
	277	rc = LAPB_CONNECTED;
	278	if (lapb->state == LAPB_STATE_3 \|\| lapb->state == LAPB_STATE_4)
	279	goto out_put;
	280
	281	lapb_establish_data_link(lapb);
	282
	283	#if LAPB_DEBUG > 0
	284	printk(KERN_DEBUG "lapb: (%p) S0 -> S1\n", lapb->dev);
	285	#endif
	286	lapb->state = LAPB_STATE_1;
	287
	288	rc = LAPB_OK;
	289	out_put:
	290	lapb_put(lapb);
	291	out:
	292	return rc;
	293	}
	294
	295	int lapb_disconnect_request(struct net_device *dev)
	296	{
	297	struct lapb_cb *lapb = lapb_devtostruct(dev);
	298	int rc = LAPB_BADTOKEN;
	299
	300	if (!lapb)
	301	goto out;
	302
	303	switch (lapb->state) {
fcb261f3 JP	304	case LAPB_STATE_0:
	305	rc = LAPB_NOTCONNECTED;
	306	goto out_put;
1da177e4	307
fcb261f3	308	case LAPB_STATE_1:
1da177e4	309	#if LAPB_DEBUG > 1
fcb261f3	310	printk(KERN_DEBUG "lapb: (%p) S1 TX DISC(1)\n", lapb->dev);
1da177e4 LT	311	#endif
1da177e4 LT	312	#if LAPB_DEBUG > 0
fcb261f3	313	printk(KERN_DEBUG "lapb: (%p) S1 -> S0\n", lapb->dev);
1da177e4	314	#endif
fcb261f3 JP	315	lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
	316	lapb->state = LAPB_STATE_0;
	317	lapb_start_t1timer(lapb);
	318	rc = LAPB_NOTCONNECTED;
	319	goto out_put;
	320
	321	case LAPB_STATE_2:
	322	rc = LAPB_OK;
	323	goto out_put;
1da177e4 LT	324	}
	325
	326	lapb_clear_queues(lapb);
	327	lapb->n2count = 0;
	328	lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
	329	lapb_start_t1timer(lapb);
	330	lapb_stop_t2timer(lapb);
	331	lapb->state = LAPB_STATE_2;
	332
	333	#if LAPB_DEBUG > 1
	334	printk(KERN_DEBUG "lapb: (%p) S3 DISC(1)\n", lapb->dev);
	335	#endif
	336	#if LAPB_DEBUG > 0
	337	printk(KERN_DEBUG "lapb: (%p) S3 -> S2\n", lapb->dev);
	338	#endif
	339
	340	rc = LAPB_OK;
	341	out_put:
	342	lapb_put(lapb);
	343	out:
	344	return rc;
	345	}
	346
	347	int lapb_data_request(struct net_device dev, struct sk_buff skb)
	348	{
	349	struct lapb_cb *lapb = lapb_devtostruct(dev);
	350	int rc = LAPB_BADTOKEN;
	351
	352	if (!lapb)
	353	goto out;
	354
	355	rc = LAPB_NOTCONNECTED;
	356	if (lapb->state != LAPB_STATE_3 && lapb->state != LAPB_STATE_4)
	357	goto out_put;
	358
	359	skb_queue_tail(&lapb->write_queue, skb);
	360	lapb_kick(lapb);
	361	rc = LAPB_OK;
	362	out_put:
	363	lapb_put(lapb);
	364	out:
	365	return rc;
	366	}
	367
	368	int lapb_data_received(struct net_device dev, struct sk_buff skb)
	369	{
	370	struct lapb_cb *lapb = lapb_devtostruct(dev);
	371	int rc = LAPB_BADTOKEN;
	372
	373	if (lapb) {
	374	lapb_data_input(lapb, skb);
	375	lapb_put(lapb);
	376	rc = LAPB_OK;
	377	}
	378
	379	return rc;
	380	}
	381
	382	void lapb_connect_confirmation(struct lapb_cb *lapb, int reason)
	383	{
d97a077a	384	if (lapb->callbacks->connect_confirmation)
d97a077a	385	lapb->callbacks->connect_confirmation(lapb->dev, reason);
1da177e4 LT	386	}
	387
	388	void lapb_connect_indication(struct lapb_cb *lapb, int reason)
	389	{
d97a077a	390	if (lapb->callbacks->connect_indication)
d97a077a	391	lapb->callbacks->connect_indication(lapb->dev, reason);
1da177e4 LT	392	}
	393
	394	void lapb_disconnect_confirmation(struct lapb_cb *lapb, int reason)
	395	{
d97a077a	396	if (lapb->callbacks->disconnect_confirmation)
d97a077a	397	lapb->callbacks->disconnect_confirmation(lapb->dev, reason);
1da177e4 LT	398	}
	399
	400	void lapb_disconnect_indication(struct lapb_cb *lapb, int reason)
	401	{
d97a077a	402	if (lapb->callbacks->disconnect_indication)
d97a077a	403	lapb->callbacks->disconnect_indication(lapb->dev, reason);
1da177e4 LT	404	}
	405
	406	int lapb_data_indication(struct lapb_cb lapb, struct sk_buff skb)
	407	{
d97a077a	408	if (lapb->callbacks->data_indication)
d97a077a	409	return lapb->callbacks->data_indication(lapb->dev, skb);
1da177e4 LT	410
1da177e4 LT	411	kfree_skb(skb);
0e8635a8	412	return NET_RX_SUCCESS; /* For now; must be != NET_RX_DROP */
1da177e4 LT	413	}
	414
	415	int lapb_data_transmit(struct lapb_cb lapb, struct sk_buff skb)
	416	{
	417	int used = 0;
	418
d97a077a	419	if (lapb->callbacks->data_transmit) {
d97a077a	420	lapb->callbacks->data_transmit(lapb->dev, skb);
1da177e4 LT	421	used = 1;
	422	}
	423
	424	return used;
	425	}
	426
	427	EXPORT_SYMBOL(lapb_register);
	428	EXPORT_SYMBOL(lapb_unregister);
	429	EXPORT_SYMBOL(lapb_getparms);
	430	EXPORT_SYMBOL(lapb_setparms);
	431	EXPORT_SYMBOL(lapb_connect_request);
	432	EXPORT_SYMBOL(lapb_disconnect_request);
	433	EXPORT_SYMBOL(lapb_data_request);
	434	EXPORT_SYMBOL(lapb_data_received);
	435
	436	static int __init lapb_init(void)
	437	{
	438	return 0;
	439	}
	440
	441	static void __exit lapb_exit(void)
	442	{
	443	WARN_ON(!list_empty(&lapb_list));
	444	}
	445
	446	MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
	447	MODULE_DESCRIPTION("The X.25 Link Access Procedure B link layer protocol");
	448	MODULE_LICENSE("GPL");
	449
	450	module_init(lapb_init);
	451	module_exit(lapb_exit);