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v3.1
 
  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 */
 17
 
 
 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>
 32#include <linux/slab.h>
 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
 43static LIST_HEAD(lapb_list);
 44static DEFINE_RWLOCK(lapb_list_lock);
 45
 46/*
 47 *	Free an allocated lapb control block.
 48 */
 49static void lapb_free_cb(struct lapb_cb *lapb)
 50{
 51	kfree(lapb);
 52}
 53
 54static __inline__ void lapb_hold(struct lapb_cb *lapb)
 55{
 56	atomic_inc(&lapb->refcnt);
 57}
 58
 59static __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 */
 68static 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 */
 79static void __lapb_insert_cb(struct lapb_cb *lapb)
 80{
 81	list_add(&lapb->node, &lapb_list);
 82	lapb_hold(lapb);
 83}
 84
 85static 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
104static 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 */
117static struct lapb_cb *lapb_create_cb(void)
118{
119	struct lapb_cb *lapb = kzalloc(sizeof(*lapb), GFP_ATOMIC);
120
121
122	if (!lapb)
123		goto out;
124
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);
 
 
138out:
139	return lapb;
140}
141
142int lapb_register(struct net_device *dev, struct lapb_register_struct *callbacks)
 
143{
144	struct lapb_cb *lapb;
145	int rc = LAPB_BADTOKEN;
146
147	write_lock_bh(&lapb_list_lock);
148
149	lapb = __lapb_devtostruct(dev);
150	if (lapb) {
151		lapb_put(lapb);
152		goto out;
153	}
154
155	lapb = lapb_create_cb();
156	rc = LAPB_NOMEM;
157	if (!lapb)
158		goto out;
159
160	lapb->dev       = dev;
161	lapb->callbacks = *callbacks;
162
163	__lapb_insert_cb(lapb);
164
165	lapb_start_t1timer(lapb);
166
167	rc = LAPB_OK;
168out:
169	write_unlock_bh(&lapb_list_lock);
170	return rc;
171}
 
172
173int lapb_unregister(struct net_device *dev)
174{
175	struct lapb_cb *lapb;
176	int rc = LAPB_BADTOKEN;
177
178	write_lock_bh(&lapb_list_lock);
179	lapb = __lapb_devtostruct(dev);
180	if (!lapb)
181		goto out;
 
 
 
 
 
 
 
182
183	lapb_stop_t1timer(lapb);
184	lapb_stop_t2timer(lapb);
185
186	lapb_clear_queues(lapb);
187
 
 
 
 
 
 
188	__lapb_remove_cb(lapb);
189
190	lapb_put(lapb);
191	rc = LAPB_OK;
192out:
193	write_unlock_bh(&lapb_list_lock);
194	return rc;
195}
 
196
197int lapb_getparms(struct net_device *dev, struct lapb_parms_struct *parms)
198{
199	int rc = LAPB_BADTOKEN;
200	struct lapb_cb *lapb = lapb_devtostruct(dev);
201
202	if (!lapb)
203		goto out;
204
 
 
205	parms->t1      = lapb->t1 / HZ;
206	parms->t2      = lapb->t2 / HZ;
207	parms->n2      = lapb->n2;
208	parms->n2count = lapb->n2count;
209	parms->state   = lapb->state;
210	parms->window  = lapb->window;
211	parms->mode    = lapb->mode;
212
213	if (!timer_pending(&lapb->t1timer))
214		parms->t1timer = 0;
215	else
216		parms->t1timer = (lapb->t1timer.expires - jiffies) / HZ;
217
218	if (!timer_pending(&lapb->t2timer))
219		parms->t2timer = 0;
220	else
221		parms->t2timer = (lapb->t2timer.expires - jiffies) / HZ;
222
 
223	lapb_put(lapb);
224	rc = LAPB_OK;
225out:
226	return rc;
227}
 
228
229int lapb_setparms(struct net_device *dev, struct lapb_parms_struct *parms)
230{
231	int rc = LAPB_BADTOKEN;
232	struct lapb_cb *lapb = lapb_devtostruct(dev);
233
234	if (!lapb)
235		goto out;
236
 
 
237	rc = LAPB_INVALUE;
238	if (parms->t1 < 1 || parms->t2 < 1 || parms->n2 < 1)
239		goto out_put;
240
241	if (lapb->state == LAPB_STATE_0) {
242		if (parms->mode & LAPB_EXTENDED) {
243			if (parms->window < 1 || parms->window > 127)
244				goto out_put;
245		} else {
246			if (parms->window < 1 || parms->window > 7)
247				goto out_put;
248		}
249		lapb->mode    = parms->mode;
250		lapb->window  = parms->window;
251	}
252
253	lapb->t1    = parms->t1 * HZ;
254	lapb->t2    = parms->t2 * HZ;
255	lapb->n2    = parms->n2;
256
257	rc = LAPB_OK;
258out_put:
 
259	lapb_put(lapb);
260out:
261	return rc;
262}
 
263
264int lapb_connect_request(struct net_device *dev)
265{
266	struct lapb_cb *lapb = lapb_devtostruct(dev);
267	int rc = LAPB_BADTOKEN;
268
269	if (!lapb)
270		goto out;
271
 
 
272	rc = LAPB_OK;
273	if (lapb->state == LAPB_STATE_1)
274		goto out_put;
275
276	rc = LAPB_CONNECTED;
277	if (lapb->state == LAPB_STATE_3 || lapb->state == LAPB_STATE_4)
278		goto out_put;
279
280	lapb_establish_data_link(lapb);
281
282#if LAPB_DEBUG > 0
283	printk(KERN_DEBUG "lapb: (%p) S0 -> S1\n", lapb->dev);
284#endif
285	lapb->state = LAPB_STATE_1;
286
287	rc = LAPB_OK;
288out_put:
 
289	lapb_put(lapb);
290out:
291	return rc;
292}
 
293
294int lapb_disconnect_request(struct net_device *dev)
295{
296	struct lapb_cb *lapb = lapb_devtostruct(dev);
297	int rc = LAPB_BADTOKEN;
298
299	if (!lapb)
300		goto out;
301
302	switch (lapb->state) {
303	case LAPB_STATE_0:
304		rc = LAPB_NOTCONNECTED;
305		goto out_put;
306
307	case LAPB_STATE_1:
308#if LAPB_DEBUG > 1
309		printk(KERN_DEBUG "lapb: (%p) S1 TX DISC(1)\n", lapb->dev);
310#endif
311#if LAPB_DEBUG > 0
312		printk(KERN_DEBUG "lapb: (%p) S1 -> S0\n", lapb->dev);
313#endif
314		lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
315		lapb->state = LAPB_STATE_0;
316		lapb_start_t1timer(lapb);
317		rc = LAPB_NOTCONNECTED;
318		goto out_put;
319
320	case LAPB_STATE_2:
321		rc = LAPB_OK;
322		goto out_put;
323	}
324
325	lapb_clear_queues(lapb);
326	lapb->n2count = 0;
327	lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
328	lapb_start_t1timer(lapb);
329	lapb_stop_t2timer(lapb);
330	lapb->state = LAPB_STATE_2;
331
332#if LAPB_DEBUG > 1
333	printk(KERN_DEBUG "lapb: (%p) S3 DISC(1)\n", lapb->dev);
334#endif
335#if LAPB_DEBUG > 0
336	printk(KERN_DEBUG "lapb: (%p) S3 -> S2\n", lapb->dev);
337#endif
338
339	rc = LAPB_OK;
340out_put:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
341	lapb_put(lapb);
342out:
343	return rc;
344}
 
345
346int lapb_data_request(struct net_device *dev, struct sk_buff *skb)
347{
348	struct lapb_cb *lapb = lapb_devtostruct(dev);
349	int rc = LAPB_BADTOKEN;
350
351	if (!lapb)
352		goto out;
353
 
 
354	rc = LAPB_NOTCONNECTED;
355	if (lapb->state != LAPB_STATE_3 && lapb->state != LAPB_STATE_4)
356		goto out_put;
357
358	skb_queue_tail(&lapb->write_queue, skb);
359	lapb_kick(lapb);
360	rc = LAPB_OK;
361out_put:
 
362	lapb_put(lapb);
363out:
364	return rc;
365}
 
366
367int lapb_data_received(struct net_device *dev, struct sk_buff *skb)
368{
369	struct lapb_cb *lapb = lapb_devtostruct(dev);
370	int rc = LAPB_BADTOKEN;
371
372	if (lapb) {
 
373		lapb_data_input(lapb, skb);
 
374		lapb_put(lapb);
375		rc = LAPB_OK;
376	}
377
378	return rc;
379}
 
380
381void lapb_connect_confirmation(struct lapb_cb *lapb, int reason)
382{
383	if (lapb->callbacks.connect_confirmation)
384		lapb->callbacks.connect_confirmation(lapb->dev, reason);
385}
386
387void lapb_connect_indication(struct lapb_cb *lapb, int reason)
388{
389	if (lapb->callbacks.connect_indication)
390		lapb->callbacks.connect_indication(lapb->dev, reason);
391}
392
393void lapb_disconnect_confirmation(struct lapb_cb *lapb, int reason)
394{
395	if (lapb->callbacks.disconnect_confirmation)
396		lapb->callbacks.disconnect_confirmation(lapb->dev, reason);
397}
398
399void lapb_disconnect_indication(struct lapb_cb *lapb, int reason)
400{
401	if (lapb->callbacks.disconnect_indication)
402		lapb->callbacks.disconnect_indication(lapb->dev, reason);
403}
404
405int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *skb)
406{
407	if (lapb->callbacks.data_indication)
408		return lapb->callbacks.data_indication(lapb->dev, skb);
409
410	kfree_skb(skb);
411	return NET_RX_SUCCESS; /* For now; must be != NET_RX_DROP */
412}
413
414int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *skb)
415{
416	int used = 0;
417
418	if (lapb->callbacks.data_transmit) {
419		lapb->callbacks.data_transmit(lapb->dev, skb);
420		used = 1;
421	}
422
423	return used;
424}
425
426EXPORT_SYMBOL(lapb_register);
427EXPORT_SYMBOL(lapb_unregister);
428EXPORT_SYMBOL(lapb_getparms);
429EXPORT_SYMBOL(lapb_setparms);
430EXPORT_SYMBOL(lapb_connect_request);
431EXPORT_SYMBOL(lapb_disconnect_request);
432EXPORT_SYMBOL(lapb_data_request);
433EXPORT_SYMBOL(lapb_data_received);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
434
435static int __init lapb_init(void)
436{
437	return 0;
438}
439
440static void __exit lapb_exit(void)
441{
442	WARN_ON(!list_empty(&lapb_list));
 
 
443}
444
445MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
446MODULE_DESCRIPTION("The X.25 Link Access Procedure B link layer protocol");
447MODULE_LICENSE("GPL");
448
449module_init(lapb_init);
450module_exit(lapb_exit);
v6.2
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *	LAPB release 002
  4 *
  5 *	This code REQUIRES 2.1.15 or higher/ NET3.038
  6 *
 
 
 
 
 
 
  7 *	History
  8 *	LAPB 001	Jonathan Naylor	Started Coding
  9 *	LAPB 002	Jonathan Naylor	New timer architecture.
 10 *	2000-10-29	Henner Eisen	lapb_data_indication() return status.
 11 */
 12
 13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 14
 15#include <linux/module.h>
 16#include <linux/errno.h>
 17#include <linux/types.h>
 18#include <linux/socket.h>
 19#include <linux/in.h>
 20#include <linux/kernel.h>
 21#include <linux/jiffies.h>
 22#include <linux/timer.h>
 23#include <linux/string.h>
 24#include <linux/sockios.h>
 25#include <linux/net.h>
 26#include <linux/inet.h>
 27#include <linux/if_arp.h>
 28#include <linux/skbuff.h>
 29#include <linux/slab.h>
 30#include <net/sock.h>
 31#include <linux/uaccess.h>
 
 32#include <linux/fcntl.h>
 33#include <linux/mm.h>
 34#include <linux/interrupt.h>
 35#include <linux/stat.h>
 36#include <linux/init.h>
 37#include <net/lapb.h>
 38
 39static LIST_HEAD(lapb_list);
 40static DEFINE_RWLOCK(lapb_list_lock);
 41
 42/*
 43 *	Free an allocated lapb control block.
 44 */
 45static void lapb_free_cb(struct lapb_cb *lapb)
 46{
 47	kfree(lapb);
 48}
 49
 50static __inline__ void lapb_hold(struct lapb_cb *lapb)
 51{
 52	refcount_inc(&lapb->refcnt);
 53}
 54
 55static __inline__ void lapb_put(struct lapb_cb *lapb)
 56{
 57	if (refcount_dec_and_test(&lapb->refcnt))
 58		lapb_free_cb(lapb);
 59}
 60
 61/*
 62 *	Socket removal during an interrupt is now safe.
 63 */
 64static void __lapb_remove_cb(struct lapb_cb *lapb)
 65{
 66	if (lapb->node.next) {
 67		list_del(&lapb->node);
 68		lapb_put(lapb);
 69	}
 70}
 71
 72/*
 73 *	Add a socket to the bound sockets list.
 74 */
 75static void __lapb_insert_cb(struct lapb_cb *lapb)
 76{
 77	list_add(&lapb->node, &lapb_list);
 78	lapb_hold(lapb);
 79}
 80
 81static struct lapb_cb *__lapb_devtostruct(struct net_device *dev)
 82{
 
 83	struct lapb_cb *lapb, *use = NULL;
 84
 85	list_for_each_entry(lapb, &lapb_list, node) {
 
 86		if (lapb->dev == dev) {
 87			use = lapb;
 88			break;
 89		}
 90	}
 91
 92	if (use)
 93		lapb_hold(use);
 94
 95	return use;
 96}
 97
 98static struct lapb_cb *lapb_devtostruct(struct net_device *dev)
 99{
100	struct lapb_cb *rc;
101
102	read_lock_bh(&lapb_list_lock);
103	rc = __lapb_devtostruct(dev);
104	read_unlock_bh(&lapb_list_lock);
105
106	return rc;
107}
108/*
109 *	Create an empty LAPB control block.
110 */
111static struct lapb_cb *lapb_create_cb(void)
112{
113	struct lapb_cb *lapb = kzalloc(sizeof(*lapb), GFP_ATOMIC);
114
 
115	if (!lapb)
116		goto out;
117
118	skb_queue_head_init(&lapb->write_queue);
119	skb_queue_head_init(&lapb->ack_queue);
120
121	timer_setup(&lapb->t1timer, NULL, 0);
122	timer_setup(&lapb->t2timer, NULL, 0);
123	lapb->t1timer_running = false;
124	lapb->t2timer_running = false;
125
126	lapb->t1      = LAPB_DEFAULT_T1;
127	lapb->t2      = LAPB_DEFAULT_T2;
128	lapb->n2      = LAPB_DEFAULT_N2;
129	lapb->mode    = LAPB_DEFAULT_MODE;
130	lapb->window  = LAPB_DEFAULT_WINDOW;
131	lapb->state   = LAPB_STATE_0;
132
133	spin_lock_init(&lapb->lock);
134	refcount_set(&lapb->refcnt, 1);
135out:
136	return lapb;
137}
138
139int lapb_register(struct net_device *dev,
140		  const struct lapb_register_struct *callbacks)
141{
142	struct lapb_cb *lapb;
143	int rc = LAPB_BADTOKEN;
144
145	write_lock_bh(&lapb_list_lock);
146
147	lapb = __lapb_devtostruct(dev);
148	if (lapb) {
149		lapb_put(lapb);
150		goto out;
151	}
152
153	lapb = lapb_create_cb();
154	rc = LAPB_NOMEM;
155	if (!lapb)
156		goto out;
157
158	lapb->dev       = dev;
159	lapb->callbacks = callbacks;
160
161	__lapb_insert_cb(lapb);
162
163	lapb_start_t1timer(lapb);
164
165	rc = LAPB_OK;
166out:
167	write_unlock_bh(&lapb_list_lock);
168	return rc;
169}
170EXPORT_SYMBOL(lapb_register);
171
172int lapb_unregister(struct net_device *dev)
173{
174	struct lapb_cb *lapb;
175	int rc = LAPB_BADTOKEN;
176
177	write_lock_bh(&lapb_list_lock);
178	lapb = __lapb_devtostruct(dev);
179	if (!lapb)
180		goto out;
181	lapb_put(lapb);
182
183	/* Wait for other refs to "lapb" to drop */
184	while (refcount_read(&lapb->refcnt) > 2)
185		usleep_range(1, 10);
186
187	spin_lock_bh(&lapb->lock);
188
189	lapb_stop_t1timer(lapb);
190	lapb_stop_t2timer(lapb);
191
192	lapb_clear_queues(lapb);
193
194	spin_unlock_bh(&lapb->lock);
195
196	/* Wait for running timers to stop */
197	del_timer_sync(&lapb->t1timer);
198	del_timer_sync(&lapb->t2timer);
199
200	__lapb_remove_cb(lapb);
201
202	lapb_put(lapb);
203	rc = LAPB_OK;
204out:
205	write_unlock_bh(&lapb_list_lock);
206	return rc;
207}
208EXPORT_SYMBOL(lapb_unregister);
209
210int lapb_getparms(struct net_device *dev, struct lapb_parms_struct *parms)
211{
212	int rc = LAPB_BADTOKEN;
213	struct lapb_cb *lapb = lapb_devtostruct(dev);
214
215	if (!lapb)
216		goto out;
217
218	spin_lock_bh(&lapb->lock);
219
220	parms->t1      = lapb->t1 / HZ;
221	parms->t2      = lapb->t2 / HZ;
222	parms->n2      = lapb->n2;
223	parms->n2count = lapb->n2count;
224	parms->state   = lapb->state;
225	parms->window  = lapb->window;
226	parms->mode    = lapb->mode;
227
228	if (!timer_pending(&lapb->t1timer))
229		parms->t1timer = 0;
230	else
231		parms->t1timer = (lapb->t1timer.expires - jiffies) / HZ;
232
233	if (!timer_pending(&lapb->t2timer))
234		parms->t2timer = 0;
235	else
236		parms->t2timer = (lapb->t2timer.expires - jiffies) / HZ;
237
238	spin_unlock_bh(&lapb->lock);
239	lapb_put(lapb);
240	rc = LAPB_OK;
241out:
242	return rc;
243}
244EXPORT_SYMBOL(lapb_getparms);
245
246int lapb_setparms(struct net_device *dev, struct lapb_parms_struct *parms)
247{
248	int rc = LAPB_BADTOKEN;
249	struct lapb_cb *lapb = lapb_devtostruct(dev);
250
251	if (!lapb)
252		goto out;
253
254	spin_lock_bh(&lapb->lock);
255
256	rc = LAPB_INVALUE;
257	if (parms->t1 < 1 || parms->t2 < 1 || parms->n2 < 1)
258		goto out_put;
259
260	if (lapb->state == LAPB_STATE_0) {
261		if (parms->mode & LAPB_EXTENDED) {
262			if (parms->window < 1 || parms->window > 127)
263				goto out_put;
264		} else {
265			if (parms->window < 1 || parms->window > 7)
266				goto out_put;
267		}
268		lapb->mode    = parms->mode;
269		lapb->window  = parms->window;
270	}
271
272	lapb->t1    = parms->t1 * HZ;
273	lapb->t2    = parms->t2 * HZ;
274	lapb->n2    = parms->n2;
275
276	rc = LAPB_OK;
277out_put:
278	spin_unlock_bh(&lapb->lock);
279	lapb_put(lapb);
280out:
281	return rc;
282}
283EXPORT_SYMBOL(lapb_setparms);
284
285int lapb_connect_request(struct net_device *dev)
286{
287	struct lapb_cb *lapb = lapb_devtostruct(dev);
288	int rc = LAPB_BADTOKEN;
289
290	if (!lapb)
291		goto out;
292
293	spin_lock_bh(&lapb->lock);
294
295	rc = LAPB_OK;
296	if (lapb->state == LAPB_STATE_1)
297		goto out_put;
298
299	rc = LAPB_CONNECTED;
300	if (lapb->state == LAPB_STATE_3 || lapb->state == LAPB_STATE_4)
301		goto out_put;
302
303	lapb_establish_data_link(lapb);
304
305	lapb_dbg(0, "(%p) S0 -> S1\n", lapb->dev);
 
 
306	lapb->state = LAPB_STATE_1;
307
308	rc = LAPB_OK;
309out_put:
310	spin_unlock_bh(&lapb->lock);
311	lapb_put(lapb);
312out:
313	return rc;
314}
315EXPORT_SYMBOL(lapb_connect_request);
316
317static int __lapb_disconnect_request(struct lapb_cb *lapb)
318{
 
 
 
 
 
 
319	switch (lapb->state) {
320	case LAPB_STATE_0:
321		return LAPB_NOTCONNECTED;
 
322
323	case LAPB_STATE_1:
324		lapb_dbg(1, "(%p) S1 TX DISC(1)\n", lapb->dev);
325		lapb_dbg(0, "(%p) S1 -> S0\n", lapb->dev);
 
 
 
 
326		lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
327		lapb->state = LAPB_STATE_0;
328		lapb_start_t1timer(lapb);
329		return LAPB_NOTCONNECTED;
 
330
331	case LAPB_STATE_2:
332		return LAPB_OK;
 
333	}
334
335	lapb_clear_queues(lapb);
336	lapb->n2count = 0;
337	lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
338	lapb_start_t1timer(lapb);
339	lapb_stop_t2timer(lapb);
340	lapb->state = LAPB_STATE_2;
341
342	lapb_dbg(1, "(%p) S3 DISC(1)\n", lapb->dev);
343	lapb_dbg(0, "(%p) S3 -> S2\n", lapb->dev);
 
 
 
 
344
345	return LAPB_OK;
346}
347
348int lapb_disconnect_request(struct net_device *dev)
349{
350	struct lapb_cb *lapb = lapb_devtostruct(dev);
351	int rc = LAPB_BADTOKEN;
352
353	if (!lapb)
354		goto out;
355
356	spin_lock_bh(&lapb->lock);
357
358	rc = __lapb_disconnect_request(lapb);
359
360	spin_unlock_bh(&lapb->lock);
361	lapb_put(lapb);
362out:
363	return rc;
364}
365EXPORT_SYMBOL(lapb_disconnect_request);
366
367int lapb_data_request(struct net_device *dev, struct sk_buff *skb)
368{
369	struct lapb_cb *lapb = lapb_devtostruct(dev);
370	int rc = LAPB_BADTOKEN;
371
372	if (!lapb)
373		goto out;
374
375	spin_lock_bh(&lapb->lock);
376
377	rc = LAPB_NOTCONNECTED;
378	if (lapb->state != LAPB_STATE_3 && lapb->state != LAPB_STATE_4)
379		goto out_put;
380
381	skb_queue_tail(&lapb->write_queue, skb);
382	lapb_kick(lapb);
383	rc = LAPB_OK;
384out_put:
385	spin_unlock_bh(&lapb->lock);
386	lapb_put(lapb);
387out:
388	return rc;
389}
390EXPORT_SYMBOL(lapb_data_request);
391
392int lapb_data_received(struct net_device *dev, struct sk_buff *skb)
393{
394	struct lapb_cb *lapb = lapb_devtostruct(dev);
395	int rc = LAPB_BADTOKEN;
396
397	if (lapb) {
398		spin_lock_bh(&lapb->lock);
399		lapb_data_input(lapb, skb);
400		spin_unlock_bh(&lapb->lock);
401		lapb_put(lapb);
402		rc = LAPB_OK;
403	}
404
405	return rc;
406}
407EXPORT_SYMBOL(lapb_data_received);
408
409void lapb_connect_confirmation(struct lapb_cb *lapb, int reason)
410{
411	if (lapb->callbacks->connect_confirmation)
412		lapb->callbacks->connect_confirmation(lapb->dev, reason);
413}
414
415void lapb_connect_indication(struct lapb_cb *lapb, int reason)
416{
417	if (lapb->callbacks->connect_indication)
418		lapb->callbacks->connect_indication(lapb->dev, reason);
419}
420
421void lapb_disconnect_confirmation(struct lapb_cb *lapb, int reason)
422{
423	if (lapb->callbacks->disconnect_confirmation)
424		lapb->callbacks->disconnect_confirmation(lapb->dev, reason);
425}
426
427void lapb_disconnect_indication(struct lapb_cb *lapb, int reason)
428{
429	if (lapb->callbacks->disconnect_indication)
430		lapb->callbacks->disconnect_indication(lapb->dev, reason);
431}
432
433int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *skb)
434{
435	if (lapb->callbacks->data_indication)
436		return lapb->callbacks->data_indication(lapb->dev, skb);
437
438	kfree_skb(skb);
439	return NET_RX_SUCCESS; /* For now; must be != NET_RX_DROP */
440}
441
442int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *skb)
443{
444	int used = 0;
445
446	if (lapb->callbacks->data_transmit) {
447		lapb->callbacks->data_transmit(lapb->dev, skb);
448		used = 1;
449	}
450
451	return used;
452}
453
454/* Handle device status changes. */
455static int lapb_device_event(struct notifier_block *this, unsigned long event,
456			     void *ptr)
457{
458	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
459	struct lapb_cb *lapb;
460
461	if (!net_eq(dev_net(dev), &init_net))
462		return NOTIFY_DONE;
463
464	if (dev->type != ARPHRD_X25)
465		return NOTIFY_DONE;
466
467	lapb = lapb_devtostruct(dev);
468	if (!lapb)
469		return NOTIFY_DONE;
470
471	spin_lock_bh(&lapb->lock);
472
473	switch (event) {
474	case NETDEV_UP:
475		lapb_dbg(0, "(%p) Interface up: %s\n", dev, dev->name);
476
477		if (netif_carrier_ok(dev)) {
478			lapb_dbg(0, "(%p): Carrier is already up: %s\n", dev,
479				 dev->name);
480			if (lapb->mode & LAPB_DCE) {
481				lapb_start_t1timer(lapb);
482			} else {
483				if (lapb->state == LAPB_STATE_0) {
484					lapb->state = LAPB_STATE_1;
485					lapb_establish_data_link(lapb);
486				}
487			}
488		}
489		break;
490	case NETDEV_GOING_DOWN:
491		if (netif_carrier_ok(dev))
492			__lapb_disconnect_request(lapb);
493		break;
494	case NETDEV_DOWN:
495		lapb_dbg(0, "(%p) Interface down: %s\n", dev, dev->name);
496		lapb_dbg(0, "(%p) S%d -> S0\n", dev, lapb->state);
497		lapb_clear_queues(lapb);
498		lapb->state = LAPB_STATE_0;
499		lapb->n2count   = 0;
500		lapb_stop_t1timer(lapb);
501		lapb_stop_t2timer(lapb);
502		break;
503	case NETDEV_CHANGE:
504		if (netif_carrier_ok(dev)) {
505			lapb_dbg(0, "(%p): Carrier detected: %s\n", dev,
506				 dev->name);
507			if (lapb->mode & LAPB_DCE) {
508				lapb_start_t1timer(lapb);
509			} else {
510				if (lapb->state == LAPB_STATE_0) {
511					lapb->state = LAPB_STATE_1;
512					lapb_establish_data_link(lapb);
513				}
514			}
515		} else {
516			lapb_dbg(0, "(%p) Carrier lost: %s\n", dev, dev->name);
517			lapb_dbg(0, "(%p) S%d -> S0\n", dev, lapb->state);
518			lapb_clear_queues(lapb);
519			lapb->state = LAPB_STATE_0;
520			lapb->n2count   = 0;
521			lapb_stop_t1timer(lapb);
522			lapb_stop_t2timer(lapb);
523		}
524		break;
525	}
526
527	spin_unlock_bh(&lapb->lock);
528	lapb_put(lapb);
529	return NOTIFY_DONE;
530}
531
532static struct notifier_block lapb_dev_notifier = {
533	.notifier_call = lapb_device_event,
534};
535
536static int __init lapb_init(void)
537{
538	return register_netdevice_notifier(&lapb_dev_notifier);
539}
540
541static void __exit lapb_exit(void)
542{
543	WARN_ON(!list_empty(&lapb_list));
544
545	unregister_netdevice_notifier(&lapb_dev_notifier);
546}
547
548MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
549MODULE_DESCRIPTION("The X.25 Link Access Procedure B link layer protocol");
550MODULE_LICENSE("GPL");
551
552module_init(lapb_init);
553module_exit(lapb_exit);