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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
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
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
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
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;
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);
451
