1 /*********************************************************************
2 *
3 * Filename: irlap.c
4 * Version: 1.0
5 * Description: IrLAP implementation for Linux
6 * Status: Stable
7 * Author: Dag Brattli <dagb@cs.uit.no>
8 * Created at: Mon Aug 4 20:40:53 1997
9 * Modified at: Tue Dec 14 09:26:44 1999
10 * Modified by: Dag Brattli <dagb@cs.uit.no>
11 *
12 * Copyright (c) 1998-1999 Dag Brattli, All Rights Reserved.
13 * Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com>
14 *
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License as
17 * published by the Free Software Foundation; either version 2 of
18 * the License, or (at your option) any later version.
19 *
20 * This program is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 * GNU General Public License for more details.
24 *
25 * You should have received a copy of the GNU General Public License
26 * along with this program; if not, see <http://www.gnu.org/licenses/>.
27 *
28 ********************************************************************/
29
30 #include <linux/slab.h>
31 #include <linux/string.h>
32 #include <linux/skbuff.h>
33 #include <linux/delay.h>
34 #include <linux/proc_fs.h>
35 #include <linux/init.h>
36 #include <linux/random.h>
37 #include <linux/module.h>
38 #include <linux/seq_file.h>
39
40 #include <net/irda/irda.h>
41 #include <net/irda/irda_device.h>
42 #include <net/irda/irqueue.h>
43 #include <net/irda/irlmp.h>
44 #include <net/irda/irlmp_frame.h>
45 #include <net/irda/irlap_frame.h>
46 #include <net/irda/irlap.h>
47 #include <net/irda/timer.h>
48 #include <net/irda/qos.h>
49
50 static hashbin_t *irlap = NULL;
51 int sysctl_slot_timeout = SLOT_TIMEOUT * 1000 / HZ;
52
53 /* This is the delay of missed pf period before generating an event
54 * to the application. The spec mandate 3 seconds, but in some cases
55 * it's way too long. - Jean II */
56 int sysctl_warn_noreply_time = 3;
57
58 extern void irlap_queue_xmit(struct irlap_cb *self, struct sk_buff *skb);
59 static void __irlap_close(struct irlap_cb *self);
60 static void irlap_init_qos_capabilities(struct irlap_cb *self,
61 struct qos_info *qos_user);
62
63 static const char *const lap_reasons[] __maybe_unused = {
64 "ERROR, NOT USED",
65 "LAP_DISC_INDICATION",
66 "LAP_NO_RESPONSE",
67 "LAP_RESET_INDICATION",
68 "LAP_FOUND_NONE",
69 "LAP_MEDIA_BUSY",
70 "LAP_PRIMARY_CONFLICT",
71 "ERROR, NOT USED",
72 };
73
irlap_init(void)74 int __init irlap_init(void)
75 {
76 /* Check if the compiler did its job properly.
77 * May happen on some ARM configuration, check with Russell King. */
78 IRDA_ASSERT(sizeof(struct xid_frame) == 14, ;);
79 IRDA_ASSERT(sizeof(struct test_frame) == 10, ;);
80 IRDA_ASSERT(sizeof(struct ua_frame) == 10, ;);
81 IRDA_ASSERT(sizeof(struct snrm_frame) == 11, ;);
82
83 /* Allocate master array */
84 irlap = hashbin_new(HB_LOCK);
85 if (irlap == NULL) {
86 net_err_ratelimited("%s: can't allocate irlap hashbin!\n",
87 __func__);
88 return -ENOMEM;
89 }
90
91 return 0;
92 }
93
irlap_cleanup(void)94 void irlap_cleanup(void)
95 {
96 IRDA_ASSERT(irlap != NULL, return;);
97
98 hashbin_delete(irlap, (FREE_FUNC) __irlap_close);
99 }
100
101 /*
102 * Function irlap_open (driver)
103 *
104 * Initialize IrLAP layer
105 *
106 */
irlap_open(struct net_device * dev,struct qos_info * qos,const char * hw_name)107 struct irlap_cb *irlap_open(struct net_device *dev, struct qos_info *qos,
108 const char *hw_name)
109 {
110 struct irlap_cb *self;
111
112 /* Initialize the irlap structure. */
113 self = kzalloc(sizeof(struct irlap_cb), GFP_KERNEL);
114 if (self == NULL)
115 return NULL;
116
117 self->magic = LAP_MAGIC;
118
119 /* Make a binding between the layers */
120 self->netdev = dev;
121 self->qos_dev = qos;
122 /* Copy hardware name */
123 if(hw_name != NULL) {
124 strlcpy(self->hw_name, hw_name, sizeof(self->hw_name));
125 } else {
126 self->hw_name[0] = '\0';
127 }
128
129 /* FIXME: should we get our own field? */
130 dev->atalk_ptr = self;
131
132 self->state = LAP_OFFLINE;
133
134 /* Initialize transmit queue */
135 skb_queue_head_init(&self->txq);
136 skb_queue_head_init(&self->txq_ultra);
137 skb_queue_head_init(&self->wx_list);
138
139 /* My unique IrLAP device address! */
140 /* We don't want the broadcast address, neither the NULL address
141 * (most often used to signify "invalid"), and we don't want an
142 * address already in use (otherwise connect won't be able
143 * to select the proper link). - Jean II */
144 do {
145 get_random_bytes(&self->saddr, sizeof(self->saddr));
146 } while ((self->saddr == 0x0) || (self->saddr == BROADCAST) ||
147 (hashbin_lock_find(irlap, self->saddr, NULL)) );
148 /* Copy to the driver */
149 memcpy(dev->dev_addr, &self->saddr, 4);
150
151 init_timer(&self->slot_timer);
152 init_timer(&self->query_timer);
153 init_timer(&self->discovery_timer);
154 init_timer(&self->final_timer);
155 init_timer(&self->poll_timer);
156 init_timer(&self->wd_timer);
157 init_timer(&self->backoff_timer);
158 init_timer(&self->media_busy_timer);
159
160 irlap_apply_default_connection_parameters(self);
161
162 self->N3 = 3; /* # connections attempts to try before giving up */
163
164 self->state = LAP_NDM;
165
166 hashbin_insert(irlap, (irda_queue_t *) self, self->saddr, NULL);
167
168 irlmp_register_link(self, self->saddr, &self->notify);
169
170 return self;
171 }
172 EXPORT_SYMBOL(irlap_open);
173
174 /*
175 * Function __irlap_close (self)
176 *
177 * Remove IrLAP and all allocated memory. Stop any pending timers.
178 *
179 */
__irlap_close(struct irlap_cb * self)180 static void __irlap_close(struct irlap_cb *self)
181 {
182 IRDA_ASSERT(self != NULL, return;);
183 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
184
185 /* Stop timers */
186 del_timer(&self->slot_timer);
187 del_timer(&self->query_timer);
188 del_timer(&self->discovery_timer);
189 del_timer(&self->final_timer);
190 del_timer(&self->poll_timer);
191 del_timer(&self->wd_timer);
192 del_timer(&self->backoff_timer);
193 del_timer(&self->media_busy_timer);
194
195 irlap_flush_all_queues(self);
196
197 self->magic = 0;
198
199 kfree(self);
200 }
201
202 /*
203 * Function irlap_close (self)
204 *
205 * Remove IrLAP instance
206 *
207 */
irlap_close(struct irlap_cb * self)208 void irlap_close(struct irlap_cb *self)
209 {
210 struct irlap_cb *lap;
211
212 IRDA_ASSERT(self != NULL, return;);
213 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
214
215 /* We used to send a LAP_DISC_INDICATION here, but this was
216 * racy. This has been move within irlmp_unregister_link()
217 * itself. Jean II */
218
219 /* Kill the LAP and all LSAPs on top of it */
220 irlmp_unregister_link(self->saddr);
221 self->notify.instance = NULL;
222
223 /* Be sure that we manage to remove ourself from the hash */
224 lap = hashbin_remove(irlap, self->saddr, NULL);
225 if (!lap) {
226 pr_debug("%s(), Didn't find myself!\n", __func__);
227 return;
228 }
229 __irlap_close(lap);
230 }
231 EXPORT_SYMBOL(irlap_close);
232
233 /*
234 * Function irlap_connect_indication (self, skb)
235 *
236 * Another device is attempting to make a connection
237 *
238 */
irlap_connect_indication(struct irlap_cb * self,struct sk_buff * skb)239 void irlap_connect_indication(struct irlap_cb *self, struct sk_buff *skb)
240 {
241 IRDA_ASSERT(self != NULL, return;);
242 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
243
244 irlap_init_qos_capabilities(self, NULL); /* No user QoS! */
245
246 irlmp_link_connect_indication(self->notify.instance, self->saddr,
247 self->daddr, &self->qos_tx, skb);
248 }
249
250 /*
251 * Function irlap_connect_response (self, skb)
252 *
253 * Service user has accepted incoming connection
254 *
255 */
irlap_connect_response(struct irlap_cb * self,struct sk_buff * userdata)256 void irlap_connect_response(struct irlap_cb *self, struct sk_buff *userdata)
257 {
258 irlap_do_event(self, CONNECT_RESPONSE, userdata, NULL);
259 }
260
261 /*
262 * Function irlap_connect_request (self, daddr, qos_user, sniff)
263 *
264 * Request connection with another device, sniffing is not implemented
265 * yet.
266 *
267 */
irlap_connect_request(struct irlap_cb * self,__u32 daddr,struct qos_info * qos_user,int sniff)268 void irlap_connect_request(struct irlap_cb *self, __u32 daddr,
269 struct qos_info *qos_user, int sniff)
270 {
271 pr_debug("%s(), daddr=0x%08x\n", __func__, daddr);
272
273 IRDA_ASSERT(self != NULL, return;);
274 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
275
276 self->daddr = daddr;
277
278 /*
279 * If the service user specifies QoS values for this connection,
280 * then use them
281 */
282 irlap_init_qos_capabilities(self, qos_user);
283
284 if ((self->state == LAP_NDM) && !self->media_busy)
285 irlap_do_event(self, CONNECT_REQUEST, NULL, NULL);
286 else
287 self->connect_pending = TRUE;
288 }
289
290 /*
291 * Function irlap_connect_confirm (self, skb)
292 *
293 * Connection request has been accepted
294 *
295 */
irlap_connect_confirm(struct irlap_cb * self,struct sk_buff * skb)296 void irlap_connect_confirm(struct irlap_cb *self, struct sk_buff *skb)
297 {
298 IRDA_ASSERT(self != NULL, return;);
299 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
300
301 irlmp_link_connect_confirm(self->notify.instance, &self->qos_tx, skb);
302 }
303
304 /*
305 * Function irlap_data_indication (self, skb)
306 *
307 * Received data frames from IR-port, so we just pass them up to
308 * IrLMP for further processing
309 *
310 */
irlap_data_indication(struct irlap_cb * self,struct sk_buff * skb,int unreliable)311 void irlap_data_indication(struct irlap_cb *self, struct sk_buff *skb,
312 int unreliable)
313 {
314 /* Hide LAP header from IrLMP layer */
315 skb_pull(skb, LAP_ADDR_HEADER+LAP_CTRL_HEADER);
316
317 irlmp_link_data_indication(self->notify.instance, skb, unreliable);
318 }
319
320
321 /*
322 * Function irlap_data_request (self, skb)
323 *
324 * Queue data for transmission, must wait until XMIT state
325 *
326 */
irlap_data_request(struct irlap_cb * self,struct sk_buff * skb,int unreliable)327 void irlap_data_request(struct irlap_cb *self, struct sk_buff *skb,
328 int unreliable)
329 {
330 IRDA_ASSERT(self != NULL, return;);
331 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
332
333 IRDA_ASSERT(skb_headroom(skb) >= (LAP_ADDR_HEADER+LAP_CTRL_HEADER),
334 return;);
335 skb_push(skb, LAP_ADDR_HEADER+LAP_CTRL_HEADER);
336
337 /*
338 * Must set frame format now so that the rest of the code knows
339 * if its dealing with an I or an UI frame
340 */
341 if (unreliable)
342 skb->data[1] = UI_FRAME;
343 else
344 skb->data[1] = I_FRAME;
345
346 /* Don't forget to refcount it - see irlmp_connect_request(). */
347 skb_get(skb);
348
349 /* Add at the end of the queue (keep ordering) - Jean II */
350 skb_queue_tail(&self->txq, skb);
351
352 /*
353 * Send event if this frame only if we are in the right state
354 * FIXME: udata should be sent first! (skb_queue_head?)
355 */
356 if ((self->state == LAP_XMIT_P) || (self->state == LAP_XMIT_S)) {
357 /* If we are not already processing the Tx queue, trigger
358 * transmission immediately - Jean II */
359 if((skb_queue_len(&self->txq) <= 1) && (!self->local_busy))
360 irlap_do_event(self, DATA_REQUEST, skb, NULL);
361 /* Otherwise, the packets will be sent normally at the
362 * next pf-poll - Jean II */
363 }
364 }
365
366 /*
367 * Function irlap_unitdata_request (self, skb)
368 *
369 * Send Ultra data. This is data that must be sent outside any connection
370 *
371 */
372 #ifdef CONFIG_IRDA_ULTRA
irlap_unitdata_request(struct irlap_cb * self,struct sk_buff * skb)373 void irlap_unitdata_request(struct irlap_cb *self, struct sk_buff *skb)
374 {
375 IRDA_ASSERT(self != NULL, return;);
376 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
377
378 IRDA_ASSERT(skb_headroom(skb) >= (LAP_ADDR_HEADER+LAP_CTRL_HEADER),
379 return;);
380 skb_push(skb, LAP_ADDR_HEADER+LAP_CTRL_HEADER);
381
382 skb->data[0] = CBROADCAST;
383 skb->data[1] = UI_FRAME;
384
385 /* Don't need to refcount, see irlmp_connless_data_request() */
386
387 skb_queue_tail(&self->txq_ultra, skb);
388
389 irlap_do_event(self, SEND_UI_FRAME, NULL, NULL);
390 }
391 #endif /*CONFIG_IRDA_ULTRA */
392
393 /*
394 * Function irlap_udata_indication (self, skb)
395 *
396 * Receive Ultra data. This is data that is received outside any connection
397 *
398 */
399 #ifdef CONFIG_IRDA_ULTRA
irlap_unitdata_indication(struct irlap_cb * self,struct sk_buff * skb)400 void irlap_unitdata_indication(struct irlap_cb *self, struct sk_buff *skb)
401 {
402 IRDA_ASSERT(self != NULL, return;);
403 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
404 IRDA_ASSERT(skb != NULL, return;);
405
406 /* Hide LAP header from IrLMP layer */
407 skb_pull(skb, LAP_ADDR_HEADER+LAP_CTRL_HEADER);
408
409 irlmp_link_unitdata_indication(self->notify.instance, skb);
410 }
411 #endif /* CONFIG_IRDA_ULTRA */
412
413 /*
414 * Function irlap_disconnect_request (void)
415 *
416 * Request to disconnect connection by service user
417 */
irlap_disconnect_request(struct irlap_cb * self)418 void irlap_disconnect_request(struct irlap_cb *self)
419 {
420 IRDA_ASSERT(self != NULL, return;);
421 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
422
423 /* Don't disconnect until all data frames are successfully sent */
424 if (!skb_queue_empty(&self->txq)) {
425 self->disconnect_pending = TRUE;
426 return;
427 }
428
429 /* Check if we are in the right state for disconnecting */
430 switch (self->state) {
431 case LAP_XMIT_P: /* FALLTHROUGH */
432 case LAP_XMIT_S: /* FALLTHROUGH */
433 case LAP_CONN: /* FALLTHROUGH */
434 case LAP_RESET_WAIT: /* FALLTHROUGH */
435 case LAP_RESET_CHECK:
436 irlap_do_event(self, DISCONNECT_REQUEST, NULL, NULL);
437 break;
438 default:
439 pr_debug("%s(), disconnect pending!\n", __func__);
440 self->disconnect_pending = TRUE;
441 break;
442 }
443 }
444
445 /*
446 * Function irlap_disconnect_indication (void)
447 *
448 * Disconnect request from other device
449 *
450 */
irlap_disconnect_indication(struct irlap_cb * self,LAP_REASON reason)451 void irlap_disconnect_indication(struct irlap_cb *self, LAP_REASON reason)
452 {
453 pr_debug("%s(), reason=%s\n", __func__, lap_reasons[reason]);
454
455 IRDA_ASSERT(self != NULL, return;);
456 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
457
458 /* Flush queues */
459 irlap_flush_all_queues(self);
460
461 switch (reason) {
462 case LAP_RESET_INDICATION:
463 pr_debug("%s(), Sending reset request!\n", __func__);
464 irlap_do_event(self, RESET_REQUEST, NULL, NULL);
465 break;
466 case LAP_NO_RESPONSE: /* FALLTHROUGH */
467 case LAP_DISC_INDICATION: /* FALLTHROUGH */
468 case LAP_FOUND_NONE: /* FALLTHROUGH */
469 case LAP_MEDIA_BUSY:
470 irlmp_link_disconnect_indication(self->notify.instance, self,
471 reason, NULL);
472 break;
473 default:
474 net_err_ratelimited("%s: Unknown reason %d\n",
475 __func__, reason);
476 }
477 }
478
479 /*
480 * Function irlap_discovery_request (gen_addr_bit)
481 *
482 * Start one single discovery operation.
483 *
484 */
irlap_discovery_request(struct irlap_cb * self,discovery_t * discovery)485 void irlap_discovery_request(struct irlap_cb *self, discovery_t *discovery)
486 {
487 struct irlap_info info;
488
489 IRDA_ASSERT(self != NULL, return;);
490 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
491 IRDA_ASSERT(discovery != NULL, return;);
492
493 pr_debug("%s(), nslots = %d\n", __func__, discovery->nslots);
494
495 IRDA_ASSERT((discovery->nslots == 1) || (discovery->nslots == 6) ||
496 (discovery->nslots == 8) || (discovery->nslots == 16),
497 return;);
498
499 /* Discovery is only possible in NDM mode */
500 if (self->state != LAP_NDM) {
501 pr_debug("%s(), discovery only possible in NDM mode\n",
502 __func__);
503 irlap_discovery_confirm(self, NULL);
504 /* Note : in theory, if we are not in NDM, we could postpone
505 * the discovery like we do for connection request.
506 * In practice, it's not worth it. If the media was busy,
507 * it's likely next time around it won't be busy. If we are
508 * in REPLY state, we will get passive discovery info & event.
509 * Jean II */
510 return;
511 }
512
513 /* Check if last discovery request finished in time, or if
514 * it was aborted due to the media busy flag. */
515 if (self->discovery_log != NULL) {
516 hashbin_delete(self->discovery_log, (FREE_FUNC) kfree);
517 self->discovery_log = NULL;
518 }
519
520 /* All operations will occur at predictable time, no need to lock */
521 self->discovery_log = hashbin_new(HB_NOLOCK);
522
523 if (self->discovery_log == NULL) {
524 net_warn_ratelimited("%s(), Unable to allocate discovery log!\n",
525 __func__);
526 return;
527 }
528
529 info.S = discovery->nslots; /* Number of slots */
530 info.s = 0; /* Current slot */
531
532 self->discovery_cmd = discovery;
533 info.discovery = discovery;
534
535 /* sysctl_slot_timeout bounds are checked in irsysctl.c - Jean II */
536 self->slot_timeout = msecs_to_jiffies(sysctl_slot_timeout);
537
538 irlap_do_event(self, DISCOVERY_REQUEST, NULL, &info);
539 }
540
541 /*
542 * Function irlap_discovery_confirm (log)
543 *
544 * A device has been discovered in front of this station, we
545 * report directly to LMP.
546 */
irlap_discovery_confirm(struct irlap_cb * self,hashbin_t * discovery_log)547 void irlap_discovery_confirm(struct irlap_cb *self, hashbin_t *discovery_log)
548 {
549 IRDA_ASSERT(self != NULL, return;);
550 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
551
552 IRDA_ASSERT(self->notify.instance != NULL, return;);
553
554 /*
555 * Check for successful discovery, since we are then allowed to clear
556 * the media busy condition (IrLAP 6.13.4 - p.94). This should allow
557 * us to make connection attempts much faster and easier (i.e. no
558 * collisions).
559 * Setting media busy to false will also generate an event allowing
560 * to process pending events in NDM state machine.
561 * Note : the spec doesn't define what's a successful discovery is.
562 * If we want Ultra to work, it's successful even if there is
563 * nobody discovered - Jean II
564 */
565 if (discovery_log)
566 irda_device_set_media_busy(self->netdev, FALSE);
567
568 /* Inform IrLMP */
569 irlmp_link_discovery_confirm(self->notify.instance, discovery_log);
570 }
571
572 /*
573 * Function irlap_discovery_indication (log)
574 *
575 * Somebody is trying to discover us!
576 *
577 */
irlap_discovery_indication(struct irlap_cb * self,discovery_t * discovery)578 void irlap_discovery_indication(struct irlap_cb *self, discovery_t *discovery)
579 {
580 IRDA_ASSERT(self != NULL, return;);
581 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
582 IRDA_ASSERT(discovery != NULL, return;);
583
584 IRDA_ASSERT(self->notify.instance != NULL, return;);
585
586 /* A device is very likely to connect immediately after it performs
587 * a successful discovery. This means that in our case, we are much
588 * more likely to receive a connection request over the medium.
589 * So, we backoff to avoid collisions.
590 * IrLAP spec 6.13.4 suggest 100ms...
591 * Note : this little trick actually make a *BIG* difference. If I set
592 * my Linux box with discovery enabled and one Ultra frame sent every
593 * second, my Palm has no trouble connecting to it every time !
594 * Jean II */
595 irda_device_set_media_busy(self->netdev, SMALL);
596
597 irlmp_link_discovery_indication(self->notify.instance, discovery);
598 }
599
600 /*
601 * Function irlap_status_indication (quality_of_link)
602 */
irlap_status_indication(struct irlap_cb * self,int quality_of_link)603 void irlap_status_indication(struct irlap_cb *self, int quality_of_link)
604 {
605 switch (quality_of_link) {
606 case STATUS_NO_ACTIVITY:
607 net_info_ratelimited("IrLAP, no activity on link!\n");
608 break;
609 case STATUS_NOISY:
610 net_info_ratelimited("IrLAP, noisy link!\n");
611 break;
612 default:
613 break;
614 }
615 irlmp_status_indication(self->notify.instance,
616 quality_of_link, LOCK_NO_CHANGE);
617 }
618
619 /*
620 * Function irlap_reset_indication (void)
621 */
irlap_reset_indication(struct irlap_cb * self)622 void irlap_reset_indication(struct irlap_cb *self)
623 {
624 IRDA_ASSERT(self != NULL, return;);
625 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
626
627 if (self->state == LAP_RESET_WAIT)
628 irlap_do_event(self, RESET_REQUEST, NULL, NULL);
629 else
630 irlap_do_event(self, RESET_RESPONSE, NULL, NULL);
631 }
632
633 /*
634 * Function irlap_reset_confirm (void)
635 */
irlap_reset_confirm(void)636 void irlap_reset_confirm(void)
637 {
638 }
639
640 /*
641 * Function irlap_generate_rand_time_slot (S, s)
642 *
643 * Generate a random time slot between s and S-1 where
644 * S = Number of slots (0 -> S-1)
645 * s = Current slot
646 */
irlap_generate_rand_time_slot(int S,int s)647 int irlap_generate_rand_time_slot(int S, int s)
648 {
649 static int rand;
650 int slot;
651
652 IRDA_ASSERT((S - s) > 0, return 0;);
653
654 rand += jiffies;
655 rand ^= (rand << 12);
656 rand ^= (rand >> 20);
657
658 slot = s + rand % (S-s);
659
660 IRDA_ASSERT((slot >= s) || (slot < S), return 0;);
661
662 return slot;
663 }
664
665 /*
666 * Function irlap_update_nr_received (nr)
667 *
668 * Remove all acknowledged frames in current window queue. This code is
669 * not intuitive and you should not try to change it. If you think it
670 * contains bugs, please mail a patch to the author instead.
671 */
irlap_update_nr_received(struct irlap_cb * self,int nr)672 void irlap_update_nr_received(struct irlap_cb *self, int nr)
673 {
674 struct sk_buff *skb = NULL;
675 int count = 0;
676
677 /*
678 * Remove all the ack-ed frames from the window queue.
679 */
680
681 /*
682 * Optimize for the common case. It is most likely that the receiver
683 * will acknowledge all the frames we have sent! So in that case we
684 * delete all frames stored in window.
685 */
686 if (nr == self->vs) {
687 while ((skb = skb_dequeue(&self->wx_list)) != NULL) {
688 dev_kfree_skb(skb);
689 }
690 /* The last acked frame is the next to send minus one */
691 self->va = nr - 1;
692 } else {
693 /* Remove all acknowledged frames in current window */
694 while ((skb_peek(&self->wx_list) != NULL) &&
695 (((self->va+1) % 8) != nr))
696 {
697 skb = skb_dequeue(&self->wx_list);
698 dev_kfree_skb(skb);
699
700 self->va = (self->va + 1) % 8;
701 count++;
702 }
703 }
704
705 /* Advance window */
706 self->window = self->window_size - skb_queue_len(&self->wx_list);
707 }
708
709 /*
710 * Function irlap_validate_ns_received (ns)
711 *
712 * Validate the next to send (ns) field from received frame.
713 */
irlap_validate_ns_received(struct irlap_cb * self,int ns)714 int irlap_validate_ns_received(struct irlap_cb *self, int ns)
715 {
716 /* ns as expected? */
717 if (ns == self->vr)
718 return NS_EXPECTED;
719 /*
720 * Stations are allowed to treat invalid NS as unexpected NS
721 * IrLAP, Recv ... with-invalid-Ns. p. 84
722 */
723 return NS_UNEXPECTED;
724
725 /* return NR_INVALID; */
726 }
727 /*
728 * Function irlap_validate_nr_received (nr)
729 *
730 * Validate the next to receive (nr) field from received frame.
731 *
732 */
irlap_validate_nr_received(struct irlap_cb * self,int nr)733 int irlap_validate_nr_received(struct irlap_cb *self, int nr)
734 {
735 /* nr as expected? */
736 if (nr == self->vs) {
737 pr_debug("%s(), expected!\n", __func__);
738 return NR_EXPECTED;
739 }
740
741 /*
742 * unexpected nr? (but within current window), first we check if the
743 * ns numbers of the frames in the current window wrap.
744 */
745 if (self->va < self->vs) {
746 if ((nr >= self->va) && (nr <= self->vs))
747 return NR_UNEXPECTED;
748 } else {
749 if ((nr >= self->va) || (nr <= self->vs))
750 return NR_UNEXPECTED;
751 }
752
753 /* Invalid nr! */
754 return NR_INVALID;
755 }
756
757 /*
758 * Function irlap_initiate_connection_state ()
759 *
760 * Initialize the connection state parameters
761 *
762 */
irlap_initiate_connection_state(struct irlap_cb * self)763 void irlap_initiate_connection_state(struct irlap_cb *self)
764 {
765 IRDA_ASSERT(self != NULL, return;);
766 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
767
768 /* Next to send and next to receive */
769 self->vs = self->vr = 0;
770
771 /* Last frame which got acked (0 - 1) % 8 */
772 self->va = 7;
773
774 self->window = 1;
775
776 self->remote_busy = FALSE;
777 self->retry_count = 0;
778 }
779
780 /*
781 * Function irlap_wait_min_turn_around (self, qos)
782 *
783 * Wait negotiated minimum turn around time, this function actually sets
784 * the number of BOS's that must be sent before the next transmitted
785 * frame in order to delay for the specified amount of time. This is
786 * done to avoid using timers, and the forbidden udelay!
787 */
irlap_wait_min_turn_around(struct irlap_cb * self,struct qos_info * qos)788 void irlap_wait_min_turn_around(struct irlap_cb *self, struct qos_info *qos)
789 {
790 __u32 min_turn_time;
791 __u32 speed;
792
793 /* Get QoS values. */
794 speed = qos->baud_rate.value;
795 min_turn_time = qos->min_turn_time.value;
796
797 /* No need to calculate XBOFs for speeds over 115200 bps */
798 if (speed > 115200) {
799 self->mtt_required = min_turn_time;
800 return;
801 }
802
803 /*
804 * Send additional BOF's for the next frame for the requested
805 * min turn time, so now we must calculate how many chars (XBOF's) we
806 * must send for the requested time period (min turn time)
807 */
808 self->xbofs_delay = irlap_min_turn_time_in_bytes(speed, min_turn_time);
809 }
810
811 /*
812 * Function irlap_flush_all_queues (void)
813 *
814 * Flush all queues
815 *
816 */
irlap_flush_all_queues(struct irlap_cb * self)817 void irlap_flush_all_queues(struct irlap_cb *self)
818 {
819 struct sk_buff* skb;
820
821 IRDA_ASSERT(self != NULL, return;);
822 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
823
824 /* Free transmission queue */
825 while ((skb = skb_dequeue(&self->txq)) != NULL)
826 dev_kfree_skb(skb);
827
828 while ((skb = skb_dequeue(&self->txq_ultra)) != NULL)
829 dev_kfree_skb(skb);
830
831 /* Free sliding window buffered packets */
832 while ((skb = skb_dequeue(&self->wx_list)) != NULL)
833 dev_kfree_skb(skb);
834 }
835
836 /*
837 * Function irlap_setspeed (self, speed)
838 *
839 * Change the speed of the IrDA port
840 *
841 */
irlap_change_speed(struct irlap_cb * self,__u32 speed,int now)842 static void irlap_change_speed(struct irlap_cb *self, __u32 speed, int now)
843 {
844 struct sk_buff *skb;
845
846 pr_debug("%s(), setting speed to %d\n", __func__, speed);
847
848 IRDA_ASSERT(self != NULL, return;);
849 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
850
851 self->speed = speed;
852
853 /* Change speed now, or just piggyback speed on frames */
854 if (now) {
855 /* Send down empty frame to trigger speed change */
856 skb = alloc_skb(0, GFP_ATOMIC);
857 if (skb)
858 irlap_queue_xmit(self, skb);
859 }
860 }
861
862 /*
863 * Function irlap_init_qos_capabilities (self, qos)
864 *
865 * Initialize QoS for this IrLAP session, What we do is to compute the
866 * intersection of the QoS capabilities for the user, driver and for
867 * IrLAP itself. Normally, IrLAP will not specify any values, but it can
868 * be used to restrict certain values.
869 */
irlap_init_qos_capabilities(struct irlap_cb * self,struct qos_info * qos_user)870 static void irlap_init_qos_capabilities(struct irlap_cb *self,
871 struct qos_info *qos_user)
872 {
873 IRDA_ASSERT(self != NULL, return;);
874 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
875 IRDA_ASSERT(self->netdev != NULL, return;);
876
877 /* Start out with the maximum QoS support possible */
878 irda_init_max_qos_capabilies(&self->qos_rx);
879
880 /* Apply drivers QoS capabilities */
881 irda_qos_compute_intersection(&self->qos_rx, self->qos_dev);
882
883 /*
884 * Check for user supplied QoS parameters. The service user is only
885 * allowed to supply these values. We check each parameter since the
886 * user may not have set all of them.
887 */
888 if (qos_user) {
889 pr_debug("%s(), Found user specified QoS!\n", __func__);
890
891 if (qos_user->baud_rate.bits)
892 self->qos_rx.baud_rate.bits &= qos_user->baud_rate.bits;
893
894 if (qos_user->max_turn_time.bits)
895 self->qos_rx.max_turn_time.bits &= qos_user->max_turn_time.bits;
896 if (qos_user->data_size.bits)
897 self->qos_rx.data_size.bits &= qos_user->data_size.bits;
898
899 if (qos_user->link_disc_time.bits)
900 self->qos_rx.link_disc_time.bits &= qos_user->link_disc_time.bits;
901 }
902
903 /* Use 500ms in IrLAP for now */
904 self->qos_rx.max_turn_time.bits &= 0x01;
905
906 /* Set data size */
907 /*self->qos_rx.data_size.bits &= 0x03;*/
908
909 irda_qos_bits_to_value(&self->qos_rx);
910 }
911
912 /*
913 * Function irlap_apply_default_connection_parameters (void, now)
914 *
915 * Use the default connection and transmission parameters
916 */
irlap_apply_default_connection_parameters(struct irlap_cb * self)917 void irlap_apply_default_connection_parameters(struct irlap_cb *self)
918 {
919 IRDA_ASSERT(self != NULL, return;);
920 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
921
922 /* xbofs : Default value in NDM */
923 self->next_bofs = 12;
924 self->bofs_count = 12;
925
926 /* NDM Speed is 9600 */
927 irlap_change_speed(self, 9600, TRUE);
928
929 /* Set mbusy when going to NDM state */
930 irda_device_set_media_busy(self->netdev, TRUE);
931
932 /*
933 * Generate random connection address for this session, which must
934 * be 7 bits wide and different from 0x00 and 0xfe
935 */
936 while ((self->caddr == 0x00) || (self->caddr == 0xfe)) {
937 get_random_bytes(&self->caddr, sizeof(self->caddr));
938 self->caddr &= 0xfe;
939 }
940
941 /* Use default values until connection has been negitiated */
942 self->slot_timeout = sysctl_slot_timeout;
943 self->final_timeout = FINAL_TIMEOUT;
944 self->poll_timeout = POLL_TIMEOUT;
945 self->wd_timeout = WD_TIMEOUT;
946
947 /* Set some default values */
948 self->qos_tx.baud_rate.value = 9600;
949 self->qos_rx.baud_rate.value = 9600;
950 self->qos_tx.max_turn_time.value = 0;
951 self->qos_rx.max_turn_time.value = 0;
952 self->qos_tx.min_turn_time.value = 0;
953 self->qos_rx.min_turn_time.value = 0;
954 self->qos_tx.data_size.value = 64;
955 self->qos_rx.data_size.value = 64;
956 self->qos_tx.window_size.value = 1;
957 self->qos_rx.window_size.value = 1;
958 self->qos_tx.additional_bofs.value = 12;
959 self->qos_rx.additional_bofs.value = 12;
960 self->qos_tx.link_disc_time.value = 0;
961 self->qos_rx.link_disc_time.value = 0;
962
963 irlap_flush_all_queues(self);
964
965 self->disconnect_pending = FALSE;
966 self->connect_pending = FALSE;
967 }
968
969 /*
970 * Function irlap_apply_connection_parameters (qos, now)
971 *
972 * Initialize IrLAP with the negotiated QoS values
973 *
974 * If 'now' is false, the speed and xbofs will be changed after the next
975 * frame is sent.
976 * If 'now' is true, the speed and xbofs is changed immediately
977 */
irlap_apply_connection_parameters(struct irlap_cb * self,int now)978 void irlap_apply_connection_parameters(struct irlap_cb *self, int now)
979 {
980 IRDA_ASSERT(self != NULL, return;);
981 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
982
983 /* Set the negotiated xbofs value */
984 self->next_bofs = self->qos_tx.additional_bofs.value;
985 if (now)
986 self->bofs_count = self->next_bofs;
987
988 /* Set the negotiated link speed (may need the new xbofs value) */
989 irlap_change_speed(self, self->qos_tx.baud_rate.value, now);
990
991 self->window_size = self->qos_tx.window_size.value;
992 self->window = self->qos_tx.window_size.value;
993
994 #ifdef CONFIG_IRDA_DYNAMIC_WINDOW
995 /*
996 * Calculate how many bytes it is possible to transmit before the
997 * link must be turned around
998 */
999 self->line_capacity =
1000 irlap_max_line_capacity(self->qos_tx.baud_rate.value,
1001 self->qos_tx.max_turn_time.value);
1002 self->bytes_left = self->line_capacity;
1003 #endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1004
1005
1006 /*
1007 * Initialize timeout values, some of the rules are listed on
1008 * page 92 in IrLAP.
1009 */
1010 IRDA_ASSERT(self->qos_tx.max_turn_time.value != 0, return;);
1011 IRDA_ASSERT(self->qos_rx.max_turn_time.value != 0, return;);
1012 /* The poll timeout applies only to the primary station.
1013 * It defines the maximum time the primary stay in XMIT mode
1014 * before timeout and turning the link around (sending a RR).
1015 * Or, this is how much we can keep the pf bit in primary mode.
1016 * Therefore, it must be lower or equal than our *OWN* max turn around.
1017 * Jean II */
1018 self->poll_timeout = msecs_to_jiffies(
1019 self->qos_tx.max_turn_time.value);
1020 /* The Final timeout applies only to the primary station.
1021 * It defines the maximum time the primary wait (mostly in RECV mode)
1022 * for an answer from the secondary station before polling it again.
1023 * Therefore, it must be greater or equal than our *PARTNER*
1024 * max turn around time - Jean II */
1025 self->final_timeout = msecs_to_jiffies(
1026 self->qos_rx.max_turn_time.value);
1027 /* The Watchdog Bit timeout applies only to the secondary station.
1028 * It defines the maximum time the secondary wait (mostly in RECV mode)
1029 * for poll from the primary station before getting annoyed.
1030 * Therefore, it must be greater or equal than our *PARTNER*
1031 * max turn around time - Jean II */
1032 self->wd_timeout = self->final_timeout * 2;
1033
1034 /*
1035 * N1 and N2 are maximum retry count for *both* the final timer
1036 * and the wd timer (with a factor 2) as defined above.
1037 * After N1 retry of a timer, we give a warning to the user.
1038 * After N2 retry, we consider the link dead and disconnect it.
1039 * Jean II
1040 */
1041
1042 /*
1043 * Set N1 to 0 if Link Disconnect/Threshold Time = 3 and set it to
1044 * 3 seconds otherwise. See page 71 in IrLAP for more details.
1045 * Actually, it's not always 3 seconds, as we allow to set
1046 * it via sysctl... Max maxtt is 500ms, and N1 need to be multiple
1047 * of 2, so 1 second is minimum we can allow. - Jean II
1048 */
1049 if (self->qos_tx.link_disc_time.value == sysctl_warn_noreply_time)
1050 /*
1051 * If we set N1 to 0, it will trigger immediately, which is
1052 * not what we want. What we really want is to disable it,
1053 * Jean II
1054 */
1055 self->N1 = -2; /* Disable - Need to be multiple of 2*/
1056 else
1057 self->N1 = sysctl_warn_noreply_time * 1000 /
1058 self->qos_rx.max_turn_time.value;
1059
1060 pr_debug("Setting N1 = %d\n", self->N1);
1061
1062 /* Set N2 to match our own disconnect time */
1063 self->N2 = self->qos_tx.link_disc_time.value * 1000 /
1064 self->qos_rx.max_turn_time.value;
1065 pr_debug("Setting N2 = %d\n", self->N2);
1066 }
1067
1068 #ifdef CONFIG_PROC_FS
1069 struct irlap_iter_state {
1070 int id;
1071 };
1072
irlap_seq_start(struct seq_file * seq,loff_t * pos)1073 static void *irlap_seq_start(struct seq_file *seq, loff_t *pos)
1074 {
1075 struct irlap_iter_state *iter = seq->private;
1076 struct irlap_cb *self;
1077
1078 /* Protect our access to the tsap list */
1079 spin_lock_irq(&irlap->hb_spinlock);
1080 iter->id = 0;
1081
1082 for (self = (struct irlap_cb *) hashbin_get_first(irlap);
1083 self; self = (struct irlap_cb *) hashbin_get_next(irlap)) {
1084 if (iter->id == *pos)
1085 break;
1086 ++iter->id;
1087 }
1088
1089 return self;
1090 }
1091
irlap_seq_next(struct seq_file * seq,void * v,loff_t * pos)1092 static void *irlap_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1093 {
1094 struct irlap_iter_state *iter = seq->private;
1095
1096 ++*pos;
1097 ++iter->id;
1098 return (void *) hashbin_get_next(irlap);
1099 }
1100
irlap_seq_stop(struct seq_file * seq,void * v)1101 static void irlap_seq_stop(struct seq_file *seq, void *v)
1102 {
1103 spin_unlock_irq(&irlap->hb_spinlock);
1104 }
1105
irlap_seq_show(struct seq_file * seq,void * v)1106 static int irlap_seq_show(struct seq_file *seq, void *v)
1107 {
1108 const struct irlap_iter_state *iter = seq->private;
1109 const struct irlap_cb *self = v;
1110
1111 IRDA_ASSERT(self->magic == LAP_MAGIC, return -EINVAL;);
1112
1113 seq_printf(seq, "irlap%d ", iter->id);
1114 seq_printf(seq, "state: %s\n",
1115 irlap_state[self->state]);
1116
1117 seq_printf(seq, " device name: %s, ",
1118 (self->netdev) ? self->netdev->name : "bug");
1119 seq_printf(seq, "hardware name: %s\n", self->hw_name);
1120
1121 seq_printf(seq, " caddr: %#02x, ", self->caddr);
1122 seq_printf(seq, "saddr: %#08x, ", self->saddr);
1123 seq_printf(seq, "daddr: %#08x\n", self->daddr);
1124
1125 seq_printf(seq, " win size: %d, ",
1126 self->window_size);
1127 seq_printf(seq, "win: %d, ", self->window);
1128 #ifdef CONFIG_IRDA_DYNAMIC_WINDOW
1129 seq_printf(seq, "line capacity: %d, ",
1130 self->line_capacity);
1131 seq_printf(seq, "bytes left: %d\n", self->bytes_left);
1132 #endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1133 seq_printf(seq, " tx queue len: %d ",
1134 skb_queue_len(&self->txq));
1135 seq_printf(seq, "win queue len: %d ",
1136 skb_queue_len(&self->wx_list));
1137 seq_printf(seq, "rbusy: %s", self->remote_busy ?
1138 "TRUE" : "FALSE");
1139 seq_printf(seq, " mbusy: %s\n", self->media_busy ?
1140 "TRUE" : "FALSE");
1141
1142 seq_printf(seq, " retrans: %d ", self->retry_count);
1143 seq_printf(seq, "vs: %d ", self->vs);
1144 seq_printf(seq, "vr: %d ", self->vr);
1145 seq_printf(seq, "va: %d\n", self->va);
1146
1147 seq_printf(seq, " qos\tbps\tmaxtt\tdsize\twinsize\taddbofs\tmintt\tldisc\tcomp\n");
1148
1149 seq_printf(seq, " tx\t%d\t",
1150 self->qos_tx.baud_rate.value);
1151 seq_printf(seq, "%d\t",
1152 self->qos_tx.max_turn_time.value);
1153 seq_printf(seq, "%d\t",
1154 self->qos_tx.data_size.value);
1155 seq_printf(seq, "%d\t",
1156 self->qos_tx.window_size.value);
1157 seq_printf(seq, "%d\t",
1158 self->qos_tx.additional_bofs.value);
1159 seq_printf(seq, "%d\t",
1160 self->qos_tx.min_turn_time.value);
1161 seq_printf(seq, "%d\t",
1162 self->qos_tx.link_disc_time.value);
1163 seq_printf(seq, "\n");
1164
1165 seq_printf(seq, " rx\t%d\t",
1166 self->qos_rx.baud_rate.value);
1167 seq_printf(seq, "%d\t",
1168 self->qos_rx.max_turn_time.value);
1169 seq_printf(seq, "%d\t",
1170 self->qos_rx.data_size.value);
1171 seq_printf(seq, "%d\t",
1172 self->qos_rx.window_size.value);
1173 seq_printf(seq, "%d\t",
1174 self->qos_rx.additional_bofs.value);
1175 seq_printf(seq, "%d\t",
1176 self->qos_rx.min_turn_time.value);
1177 seq_printf(seq, "%d\n",
1178 self->qos_rx.link_disc_time.value);
1179
1180 return 0;
1181 }
1182
1183 static const struct seq_operations irlap_seq_ops = {
1184 .start = irlap_seq_start,
1185 .next = irlap_seq_next,
1186 .stop = irlap_seq_stop,
1187 .show = irlap_seq_show,
1188 };
1189
irlap_seq_open(struct inode * inode,struct file * file)1190 static int irlap_seq_open(struct inode *inode, struct file *file)
1191 {
1192 if (irlap == NULL)
1193 return -EINVAL;
1194
1195 return seq_open_private(file, &irlap_seq_ops,
1196 sizeof(struct irlap_iter_state));
1197 }
1198
1199 const struct file_operations irlap_seq_fops = {
1200 .owner = THIS_MODULE,
1201 .open = irlap_seq_open,
1202 .read = seq_read,
1203 .llseek = seq_lseek,
1204 .release = seq_release_private,
1205 };
1206
1207 #endif /* CONFIG_PROC_FS */
1208