1 /*********************************************************************
2 *
3 * Filename: irttp.c
4 * Version: 1.2
5 * Description: Tiny Transport Protocol (TTP) implementation
6 * Status: Stable
7 * Author: Dag Brattli <dagb@cs.uit.no>
8 * Created at: Sun Aug 31 20:14:31 1997
9 * Modified at: Wed Jan 5 11:31:27 2000
10 * Modified by: Dag Brattli <dagb@cs.uit.no>
11 *
12 * Copyright (c) 1998-2000 Dag Brattli <dagb@cs.uit.no>,
13 * All Rights Reserved.
14 * Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com>
15 *
16 * This program is free software; you can redistribute it and/or
17 * modify it under the terms of the GNU General Public License as
18 * published by the Free Software Foundation; either version 2 of
19 * the License, or (at your option) any later version.
20 *
21 * Neither Dag Brattli nor University of Tromsų admit liability nor
22 * provide warranty for any of this software. This material is
23 * provided "AS-IS" and at no charge.
24 *
25 ********************************************************************/
26
27 #include <linux/config.h>
28 #include <linux/skbuff.h>
29 #include <linux/init.h>
30 #include <linux/seq_file.h>
31
32 #include <asm/byteorder.h>
33 #include <asm/unaligned.h>
34
35 #include <net/irda/irda.h>
36 #include <net/irda/irlap.h>
37 #include <net/irda/irlmp.h>
38 #include <net/irda/parameters.h>
39 #include <net/irda/irttp.h>
40
41 static struct irttp_cb *irttp = NULL;
42
43 static void __irttp_close_tsap(struct tsap_cb *self);
44
45 static int irttp_data_indication(void *instance, void *sap,
46 struct sk_buff *skb);
47 static int irttp_udata_indication(void *instance, void *sap,
48 struct sk_buff *skb);
49 static void irttp_disconnect_indication(void *instance, void *sap,
50 LM_REASON reason, struct sk_buff *);
51 static void irttp_connect_indication(void *instance, void *sap,
52 struct qos_info *qos, __u32 max_sdu_size,
53 __u8 header_size, struct sk_buff *skb);
54 static void irttp_connect_confirm(void *instance, void *sap,
55 struct qos_info *qos, __u32 max_sdu_size,
56 __u8 header_size, struct sk_buff *skb);
57 static void irttp_run_tx_queue(struct tsap_cb *self);
58 static void irttp_run_rx_queue(struct tsap_cb *self);
59
60 static void irttp_flush_queues(struct tsap_cb *self);
61 static void irttp_fragment_skb(struct tsap_cb *self, struct sk_buff *skb);
62 static struct sk_buff *irttp_reassemble_skb(struct tsap_cb *self);
63 static void irttp_todo_expired(unsigned long data);
64 static int irttp_param_max_sdu_size(void *instance, irda_param_t *param,
65 int get);
66
67 static void irttp_flow_indication(void *instance, void *sap, LOCAL_FLOW flow);
68 static void irttp_status_indication(void *instance,
69 LINK_STATUS link, LOCK_STATUS lock);
70
71 /* Information for parsing parameters in IrTTP */
72 static pi_minor_info_t pi_minor_call_table[] = {
73 { NULL, 0 }, /* 0x00 */
74 { irttp_param_max_sdu_size, PV_INTEGER | PV_BIG_ENDIAN } /* 0x01 */
75 };
76 static pi_major_info_t pi_major_call_table[] = {{ pi_minor_call_table, 2 }};
77 static pi_param_info_t param_info = { pi_major_call_table, 1, 0x0f, 4 };
78
79 /************************ GLOBAL PROCEDURES ************************/
80
81 /*
82 * Function irttp_init (void)
83 *
84 * Initialize the IrTTP layer. Called by module initialization code
85 *
86 */
87 int __init irttp_init(void)
88 {
89 /* Initialize the irttp structure. */
90 if (irttp == NULL) {
91 irttp = kmalloc(sizeof(struct irttp_cb), GFP_KERNEL);
92 if (irttp == NULL)
93 return -ENOMEM;
94 }
95 memset(irttp, 0, sizeof(struct irttp_cb));
96
97 irttp->magic = TTP_MAGIC;
98
99 irttp->tsaps = hashbin_new(HB_LOCK);
100 if (!irttp->tsaps) {
101 ERROR("%s: can't allocate IrTTP hashbin!\n", __FUNCTION__);
102 return -ENOMEM;
103 }
104
105 return 0;
106 }
107
108 /*
109 * Function irttp_cleanup (void)
110 *
111 * Called by module destruction/cleanup code
112 *
113 */
114 void __exit irttp_cleanup(void)
115 {
116 /* Check for main structure */
117 ASSERT(irttp != NULL, return;);
118 ASSERT(irttp->magic == TTP_MAGIC, return;);
119
120 /*
121 * Delete hashbin and close all TSAP instances in it
122 */
123 hashbin_delete(irttp->tsaps, (FREE_FUNC) __irttp_close_tsap);
124
125 irttp->magic = 0;
126
127 /* De-allocate main structure */
128 kfree(irttp);
129
130 irttp = NULL;
131 }
132
133 /*************************** SUBROUTINES ***************************/
134
135 /*
136 * Function irttp_start_todo_timer (self, timeout)
137 *
138 * Start todo timer.
139 *
140 * Made it more effient and unsensitive to race conditions - Jean II
141 */
142 static inline void irttp_start_todo_timer(struct tsap_cb *self, int timeout)
143 {
144 /* Set new value for timer */
145 mod_timer(&self->todo_timer, jiffies + timeout);
146 }
147
148 /*
149 * Function irttp_todo_expired (data)
150 *
151 * Todo timer has expired!
152 *
153 * One of the restriction of the timer is that it is run only on the timer
154 * interrupt which run every 10ms. This mean that even if you set the timer
155 * with a delay of 0, it may take up to 10ms before it's run.
156 * So, to minimise latency and keep cache fresh, we try to avoid using
157 * it as much as possible.
158 * Note : we can't use tasklets, because they can't be asynchronously
159 * killed (need user context), and we can't guarantee that here...
160 * Jean II
161 */
162 static void irttp_todo_expired(unsigned long data)
163 {
164 struct tsap_cb *self = (struct tsap_cb *) data;
165
166 /* Check that we still exist */
167 if (!self || self->magic != TTP_TSAP_MAGIC)
168 return;
169
170 IRDA_DEBUG(4, "%s(instance=%p)\n", __FUNCTION__, self);
171
172 /* Try to make some progress, especially on Tx side - Jean II */
173 irttp_run_rx_queue(self);
174 irttp_run_tx_queue(self);
175
176 /* Check if time for disconnect */
177 if (test_bit(0, &self->disconnect_pend)) {
178 /* Check if it's possible to disconnect yet */
179 if (skb_queue_empty(&self->tx_queue)) {
180 /* Make sure disconnect is not pending anymore */
181 clear_bit(0, &self->disconnect_pend); /* FALSE */
182
183 /* Note : self->disconnect_skb may be NULL */
184 irttp_disconnect_request(self, self->disconnect_skb,
185 P_NORMAL);
186 self->disconnect_skb = NULL;
187 } else {
188 /* Try again later */
189 irttp_start_todo_timer(self, HZ/10);
190
191 /* No reason to try and close now */
192 return;
193 }
194 }
195
196 /* Check if it's closing time */
197 if (self->close_pend)
198 /* Finish cleanup */
199 irttp_close_tsap(self);
200 }
201
202 /*
203 * Function irttp_flush_queues (self)
204 *
205 * Flushes (removes all frames) in transitt-buffer (tx_list)
206 */
207 void irttp_flush_queues(struct tsap_cb *self)
208 {
209 struct sk_buff* skb;
210
211 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
212
213 ASSERT(self != NULL, return;);
214 ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
215
216 /* Deallocate frames waiting to be sent */
217 while ((skb = skb_dequeue(&self->tx_queue)) != NULL)
218 dev_kfree_skb(skb);
219
220 /* Deallocate received frames */
221 while ((skb = skb_dequeue(&self->rx_queue)) != NULL)
222 dev_kfree_skb(skb);
223
224 /* Deallocate received fragments */
225 while ((skb = skb_dequeue(&self->rx_fragments)) != NULL)
226 dev_kfree_skb(skb);
227 }
228
229 /*
230 * Function irttp_reassemble (self)
231 *
232 * Makes a new (continuous) skb of all the fragments in the fragment
233 * queue
234 *
235 */
236 static struct sk_buff *irttp_reassemble_skb(struct tsap_cb *self)
237 {
238 struct sk_buff *skb, *frag;
239 int n = 0; /* Fragment index */
240
241 ASSERT(self != NULL, return NULL;);
242 ASSERT(self->magic == TTP_TSAP_MAGIC, return NULL;);
243
244 IRDA_DEBUG(2, "%s(), self->rx_sdu_size=%d\n", __FUNCTION__,
245 self->rx_sdu_size);
246
247 skb = dev_alloc_skb(TTP_HEADER + self->rx_sdu_size);
248 if (!skb)
249 return NULL;
250
251 /*
252 * Need to reserve space for TTP header in case this skb needs to
253 * be requeued in case delivery failes
254 */
255 skb_reserve(skb, TTP_HEADER);
256 skb_put(skb, self->rx_sdu_size);
257
258 /*
259 * Copy all fragments to a new buffer
260 */
261 while ((frag = skb_dequeue(&self->rx_fragments)) != NULL) {
262 memcpy(skb->data+n, frag->data, frag->len);
263 n += frag->len;
264
265 dev_kfree_skb(frag);
266 }
267
268 IRDA_DEBUG(2,
269 "%s(), frame len=%d, rx_sdu_size=%d, rx_max_sdu_size=%d\n",
270 __FUNCTION__, n, self->rx_sdu_size, self->rx_max_sdu_size);
271 /* Note : irttp_run_rx_queue() calculate self->rx_sdu_size
272 * by summing the size of all fragments, so we should always
273 * have n == self->rx_sdu_size, except in cases where we
274 * droped the last fragment (when self->rx_sdu_size exceed
275 * self->rx_max_sdu_size), where n < self->rx_sdu_size.
276 * Jean II */
277 ASSERT(n <= self->rx_sdu_size, n = self->rx_sdu_size;);
278
279 /* Set the new length */
280 skb_trim(skb, n);
281
282 self->rx_sdu_size = 0;
283
284 return skb;
285 }
286
287 /*
288 * Function irttp_fragment_skb (skb)
289 *
290 * Fragments a frame and queues all the fragments for transmission
291 *
292 */
293 static inline void irttp_fragment_skb(struct tsap_cb *self,
294 struct sk_buff *skb)
295 {
296 struct sk_buff *frag;
297 __u8 *frame;
298
299 IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
300
301 ASSERT(self != NULL, return;);
302 ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
303 ASSERT(skb != NULL, return;);
304
305 /*
306 * Split frame into a number of segments
307 */
308 while (skb->len > self->max_seg_size) {
309 IRDA_DEBUG(2, "%s(), fragmenting ...\n", __FUNCTION__);
310
311 /* Make new segment */
312 frag = dev_alloc_skb(self->max_seg_size+self->max_header_size);
313 if (!frag)
314 return;
315
316 skb_reserve(frag, self->max_header_size);
317
318 /* Copy data from the original skb into this fragment. */
319 memcpy(skb_put(frag, self->max_seg_size), skb->data,
320 self->max_seg_size);
321
322 /* Insert TTP header, with the more bit set */
323 frame = skb_push(frag, TTP_HEADER);
324 frame[0] = TTP_MORE;
325
326 /* Hide the copied data from the original skb */
327 skb_pull(skb, self->max_seg_size);
328
329 /* Queue fragment */
330 skb_queue_tail(&self->tx_queue, frag);
331 }
332 /* Queue what is left of the original skb */
333 IRDA_DEBUG(2, "%s(), queuing last segment\n", __FUNCTION__);
334
335 frame = skb_push(skb, TTP_HEADER);
336 frame[0] = 0x00; /* Clear more bit */
337
338 /* Queue fragment */
339 skb_queue_tail(&self->tx_queue, skb);
340 }
341
342 /*
343 * Function irttp_param_max_sdu_size (self, param)
344 *
345 * Handle the MaxSduSize parameter in the connect frames, this function
346 * will be called both when this parameter needs to be inserted into, and
347 * extracted from the connect frames
348 */
349 static int irttp_param_max_sdu_size(void *instance, irda_param_t *param,
350 int get)
351 {
352 struct tsap_cb *self;
353
354 self = (struct tsap_cb *) instance;
355
356 ASSERT(self != NULL, return -1;);
357 ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
358
359 if (get)
360 param->pv.i = self->tx_max_sdu_size;
361 else
362 self->tx_max_sdu_size = param->pv.i;
363
364 IRDA_DEBUG(1, "%s(), MaxSduSize=%d\n", __FUNCTION__, param->pv.i);
365
366 return 0;
367 }
368
369 /*************************** CLIENT CALLS ***************************/
370 /************************** LMP CALLBACKS **************************/
371 /* Everything is happily mixed up. Waiting for next clean up - Jean II */
372
373 /*
374 * Function irttp_open_tsap (stsap, notify)
375 *
376 * Create TSAP connection endpoint,
377 */
378 struct tsap_cb *irttp_open_tsap(__u8 stsap_sel, int credit, notify_t *notify)
379 {
380 struct tsap_cb *self;
381 struct lsap_cb *lsap;
382 notify_t ttp_notify;
383
384 ASSERT(irttp != NULL, return NULL;);
385 ASSERT(irttp->magic == TTP_MAGIC, return NULL;);
386
387 /* The IrLMP spec (IrLMP 1.1 p10) says that we have the right to
388 * use only 0x01-0x6F. Of course, we can use LSAP_ANY as well.
389 * JeanII */
390 if((stsap_sel != LSAP_ANY) &&
391 ((stsap_sel < 0x01) || (stsap_sel >= 0x70))) {
392 IRDA_DEBUG(0, "%s(), invalid tsap!\n", __FUNCTION__);
393 return NULL;
394 }
395
396 self = kmalloc(sizeof(struct tsap_cb), GFP_ATOMIC);
397 if (self == NULL) {
398 IRDA_DEBUG(0, "%s(), unable to kmalloc!\n", __FUNCTION__);
399 return NULL;
400 }
401 memset(self, 0, sizeof(struct tsap_cb));
402 spin_lock_init(&self->lock);
403
404 /* Initialise todo timer */
405 init_timer(&self->todo_timer);
406 self->todo_timer.data = (unsigned long) self;
407 self->todo_timer.function = &irttp_todo_expired;
408
409 /* Initialize callbacks for IrLMP to use */
410 irda_notify_init(&ttp_notify);
411 ttp_notify.connect_confirm = irttp_connect_confirm;
412 ttp_notify.connect_indication = irttp_connect_indication;
413 ttp_notify.disconnect_indication = irttp_disconnect_indication;
414 ttp_notify.data_indication = irttp_data_indication;
415 ttp_notify.udata_indication = irttp_udata_indication;
416 ttp_notify.flow_indication = irttp_flow_indication;
417 if(notify->status_indication != NULL)
418 ttp_notify.status_indication = irttp_status_indication;
419 ttp_notify.instance = self;
420 strncpy(ttp_notify.name, notify->name, NOTIFY_MAX_NAME);
421
422 self->magic = TTP_TSAP_MAGIC;
423 self->connected = FALSE;
424
425 skb_queue_head_init(&self->rx_queue);
426 skb_queue_head_init(&self->tx_queue);
427 skb_queue_head_init(&self->rx_fragments);
428 /*
429 * Create LSAP at IrLMP layer
430 */
431 lsap = irlmp_open_lsap(stsap_sel, &ttp_notify, 0);
432 if (lsap == NULL) {
433 WARNING("%s: unable to allocate LSAP!!\n", __FUNCTION__);
434 return NULL;
435 }
436
437 /*
438 * If user specified LSAP_ANY as source TSAP selector, then IrLMP
439 * will replace it with whatever source selector which is free, so
440 * the stsap_sel we have might not be valid anymore
441 */
442 self->stsap_sel = lsap->slsap_sel;
443 IRDA_DEBUG(4, "%s(), stsap_sel=%02x\n", __FUNCTION__, self->stsap_sel);
444
445 self->notify = *notify;
446 self->lsap = lsap;
447
448 hashbin_insert(irttp->tsaps, (irda_queue_t *) self, (long) self, NULL);
449
450 if (credit > TTP_RX_MAX_CREDIT)
451 self->initial_credit = TTP_RX_MAX_CREDIT;
452 else
453 self->initial_credit = credit;
454
455 return self;
456 }
457 EXPORT_SYMBOL(irttp_open_tsap);
458
459 /*
460 * Function irttp_close (handle)
461 *
462 * Remove an instance of a TSAP. This function should only deal with the
463 * deallocation of the TSAP, and resetting of the TSAPs values;
464 *
465 */
466 static void __irttp_close_tsap(struct tsap_cb *self)
467 {
468 /* First make sure we're connected. */
469 ASSERT(self != NULL, return;);
470 ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
471
472 irttp_flush_queues(self);
473
474 del_timer(&self->todo_timer);
475
476 /* This one won't be cleaned up if we are disconnect_pend + close_pend
477 * and we receive a disconnect_indication */
478 if (self->disconnect_skb)
479 dev_kfree_skb(self->disconnect_skb);
480
481 self->connected = FALSE;
482 self->magic = ~TTP_TSAP_MAGIC;
483
484 kfree(self);
485 }
486
487 /*
488 * Function irttp_close (self)
489 *
490 * Remove TSAP from list of all TSAPs and then deallocate all resources
491 * associated with this TSAP
492 *
493 * Note : because we *free* the tsap structure, it is the responsibility
494 * of the caller to make sure we are called only once and to deal with
495 * possible race conditions. - Jean II
496 */
497 int irttp_close_tsap(struct tsap_cb *self)
498 {
499 struct tsap_cb *tsap;
500
501 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
502
503 ASSERT(self != NULL, return -1;);
504 ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
505
506 /* Make sure tsap has been disconnected */
507 if (self->connected) {
508 /* Check if disconnect is not pending */
509 if (!test_bit(0, &self->disconnect_pend)) {
510 WARNING("%s: TSAP still connected!\n", __FUNCTION__);
511 irttp_disconnect_request(self, NULL, P_NORMAL);
512 }
513 self->close_pend = TRUE;
514 irttp_start_todo_timer(self, HZ/10);
515
516 return 0; /* Will be back! */
517 }
518
519 tsap = hashbin_remove(irttp->tsaps, (long) self, NULL);
520
521 ASSERT(tsap == self, return -1;);
522
523 /* Close corresponding LSAP */
524 if (self->lsap) {
525 irlmp_close_lsap(self->lsap);
526 self->lsap = NULL;
527 }
528
529 __irttp_close_tsap(self);
530
531 return 0;
532 }
533 EXPORT_SYMBOL(irttp_close_tsap);
534
535 /*
536 * Function irttp_udata_request (self, skb)
537 *
538 * Send unreliable data on this TSAP
539 *
540 */
541 int irttp_udata_request(struct tsap_cb *self, struct sk_buff *skb)
542 {
543 ASSERT(self != NULL, return -1;);
544 ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
545 ASSERT(skb != NULL, return -1;);
546
547 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
548
549 /* Check that nothing bad happens */
550 if ((skb->len == 0) || (!self->connected)) {
551 IRDA_DEBUG(1, "%s(), No data, or not connected\n",
552 __FUNCTION__);
553 goto err;
554 }
555
556 if (skb->len > self->max_seg_size) {
557 IRDA_DEBUG(1, "%s(), UData is to large for IrLAP!\n",
558 __FUNCTION__);
559 goto err;
560 }
561
562 irlmp_udata_request(self->lsap, skb);
563 self->stats.tx_packets++;
564
565 return 0;
566
567 err:
568 dev_kfree_skb(skb);
569 return -1;
570 }
571 EXPORT_SYMBOL(irttp_udata_request);
572
573
574 /*
575 * Function irttp_data_request (handle, skb)
576 *
577 * Queue frame for transmission. If SAR is enabled, fragement the frame
578 * and queue the fragments for transmission
579 */
580 int irttp_data_request(struct tsap_cb *self, struct sk_buff *skb)
581 {
582 __u8 *frame;
583 int ret;
584
585 ASSERT(self != NULL, return -1;);
586 ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
587 ASSERT(skb != NULL, return -1;);
588
589 IRDA_DEBUG(2, "%s() : queue len = %d\n", __FUNCTION__,
590 skb_queue_len(&self->tx_queue));
591
592 /* Check that nothing bad happens */
593 if ((skb->len == 0) || (!self->connected)) {
594 WARNING("%s: No data, or not connected\n", __FUNCTION__);
595 ret = -ENOTCONN;
596 goto err;
597 }
598
599 /*
600 * Check if SAR is disabled, and the frame is larger than what fits
601 * inside an IrLAP frame
602 */
603 if ((self->tx_max_sdu_size == 0) && (skb->len > self->max_seg_size)) {
604 ERROR("%s: SAR disabled, and data is to large for IrLAP!\n",
605 __FUNCTION__);
606 ret = -EMSGSIZE;
607 goto err;
608 }
609
610 /*
611 * Check if SAR is enabled, and the frame is larger than the
612 * TxMaxSduSize
613 */
614 if ((self->tx_max_sdu_size != 0) &&
615 (self->tx_max_sdu_size != TTP_SAR_UNBOUND) &&
616 (skb->len > self->tx_max_sdu_size))
617 {
618 ERROR("%s: SAR enabled, but data is larger than TxMaxSduSize!\n",
619 __FUNCTION__);
620 ret = -EMSGSIZE;
621 goto err;
622 }
623 /*
624 * Check if transmit queue is full
625 */
626 if (skb_queue_len(&self->tx_queue) >= TTP_TX_MAX_QUEUE) {
627 /*
628 * Give it a chance to empty itself
629 */
630 irttp_run_tx_queue(self);
631
632 /* Drop packet. This error code should trigger the caller
633 * to resend the data in the client code - Jean II */
634 ret = -ENOBUFS;
635 goto err;
636 }
637
638 /* Queue frame, or queue frame segments */
639 if ((self->tx_max_sdu_size == 0) || (skb->len < self->max_seg_size)) {
640 /* Queue frame */
641 ASSERT(skb_headroom(skb) >= TTP_HEADER, return -1;);
642 frame = skb_push(skb, TTP_HEADER);
643 frame[0] = 0x00; /* Clear more bit */
644
645 skb_queue_tail(&self->tx_queue, skb);
646 } else {
647 /*
648 * Fragment the frame, this function will also queue the
649 * fragments, we don't care about the fact the transmit
650 * queue may be overfilled by all the segments for a little
651 * while
652 */
653 irttp_fragment_skb(self, skb);
654 }
655
656 /* Check if we can accept more data from client */
657 if ((!self->tx_sdu_busy) &&
658 (skb_queue_len(&self->tx_queue) > TTP_TX_HIGH_THRESHOLD)) {
659 /* Tx queue filling up, so stop client. */
660 if (self->notify.flow_indication) {
661 self->notify.flow_indication(self->notify.instance,
662 self, FLOW_STOP);
663 }
664 /* self->tx_sdu_busy is the state of the client.
665 * Update state after notifying client to avoid
666 * race condition with irttp_flow_indication().
667 * If the queue empty itself after our test but before
668 * we set the flag, we will fix ourselves below in
669 * irttp_run_tx_queue().
670 * Jean II */
671 self->tx_sdu_busy = TRUE;
672 }
673
674 /* Try to make some progress */
675 irttp_run_tx_queue(self);
676
677 return 0;
678
679 err:
680 dev_kfree_skb(skb);
681 return ret;
682 }
683 EXPORT_SYMBOL(irttp_data_request);
684
685 /*
686 * Function irttp_run_tx_queue (self)
687 *
688 * Transmit packets queued for transmission (if possible)
689 *
690 */
691 static void irttp_run_tx_queue(struct tsap_cb *self)
692 {
693 struct sk_buff *skb;
694 unsigned long flags;
695 int n;
696
697 IRDA_DEBUG(2, "%s() : send_credit = %d, queue_len = %d\n",
698 __FUNCTION__,
699 self->send_credit, skb_queue_len(&self->tx_queue));
700
701 /* Get exclusive access to the tx queue, otherwise don't touch it */
702 if (irda_lock(&self->tx_queue_lock) == FALSE)
703 return;
704
705 /* Try to send out frames as long as we have credits
706 * and as long as LAP is not full. If LAP is full, it will
707 * poll us through irttp_flow_indication() - Jean II */
708 while ((self->send_credit > 0) &&
709 (!irlmp_lap_tx_queue_full(self->lsap)) &&
710 (skb = skb_dequeue(&self->tx_queue)))
711 {
712 /*
713 * Since we can transmit and receive frames concurrently,
714 * the code below is a critical region and we must assure that
715 * nobody messes with the credits while we update them.
716 */
717 spin_lock_irqsave(&self->lock, flags);
718
719 n = self->avail_credit;
720 self->avail_credit = 0;
721
722 /* Only room for 127 credits in frame */
723 if (n > 127) {
724 self->avail_credit = n-127;
725 n = 127;
726 }
727 self->remote_credit += n;
728 self->send_credit--;
729
730 spin_unlock_irqrestore(&self->lock, flags);
731
732 /*
733 * More bit must be set by the data_request() or fragment()
734 * functions
735 */
736 skb->data[0] |= (n & 0x7f);
737
738 /* Detach from socket.
739 * The current skb has a reference to the socket that sent
740 * it (skb->sk). When we pass it to IrLMP, the skb will be
741 * stored in in IrLAP (self->wx_list). When we are within
742 * IrLAP, we lose the notion of socket, so we should not
743 * have a reference to a socket. So, we drop it here.
744 *
745 * Why does it matter ?
746 * When the skb is freed (kfree_skb), if it is associated
747 * with a socket, it release buffer space on the socket
748 * (through sock_wfree() and sock_def_write_space()).
749 * If the socket no longer exist, we may crash. Hard.
750 * When we close a socket, we make sure that associated packets
751 * in IrTTP are freed. However, we have no way to cancel
752 * the packet that we have passed to IrLAP. So, if a packet
753 * remains in IrLAP (retry on the link or else) after we
754 * close the socket, we are dead !
755 * Jean II */
756 if (skb->sk != NULL) {
757 /* IrSOCK application, IrOBEX, ... */
758 skb_orphan(skb);
759 }
760 /* IrCOMM over IrTTP, IrLAN, ... */
761
762 /* Pass the skb to IrLMP - done */
763 irlmp_data_request(self->lsap, skb);
764 self->stats.tx_packets++;
765 }
766
767 /* Check if we can accept more frames from client.
768 * We don't want to wait until the todo timer to do that, and we
769 * can't use tasklets (grr...), so we are obliged to give control
770 * to client. That's ok, this test will be true not too often
771 * (max once per LAP window) and we are called from places
772 * where we can spend a bit of time doing stuff. - Jean II */
773 if ((self->tx_sdu_busy) &&
774 (skb_queue_len(&self->tx_queue) < TTP_TX_LOW_THRESHOLD) &&
775 (!self->close_pend))
776 {
777 if (self->notify.flow_indication)
778 self->notify.flow_indication(self->notify.instance,
779 self, FLOW_START);
780
781 /* self->tx_sdu_busy is the state of the client.
782 * We don't really have a race here, but it's always safer
783 * to update our state after the client - Jean II */
784 self->tx_sdu_busy = FALSE;
785 }
786
787 /* Reset lock */
788 self->tx_queue_lock = 0;
789 }
790
791 /*
792 * Function irttp_give_credit (self)
793 *
794 * Send a dataless flowdata TTP-PDU and give available credit to peer
795 * TSAP
796 */
797 static inline void irttp_give_credit(struct tsap_cb *self)
798 {
799 struct sk_buff *tx_skb = NULL;
800 unsigned long flags;
801 int n;
802
803 ASSERT(self != NULL, return;);
804 ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
805
806 IRDA_DEBUG(4, "%s() send=%d,avail=%d,remote=%d\n",
807 __FUNCTION__,
808 self->send_credit, self->avail_credit, self->remote_credit);
809
810 /* Give credit to peer */
811 tx_skb = dev_alloc_skb(64);
812 if (!tx_skb)
813 return;
814
815 /* Reserve space for LMP, and LAP header */
816 skb_reserve(tx_skb, self->max_header_size);
817
818 /*
819 * Since we can transmit and receive frames concurrently,
820 * the code below is a critical region and we must assure that
821 * nobody messes with the credits while we update them.
822 */
823 spin_lock_irqsave(&self->lock, flags);
824
825 n = self->avail_credit;
826 self->avail_credit = 0;
827
828 /* Only space for 127 credits in frame */
829 if (n > 127) {
830 self->avail_credit = n - 127;
831 n = 127;
832 }
833 self->remote_credit += n;
834
835 spin_unlock_irqrestore(&self->lock, flags);
836
837 skb_put(tx_skb, 1);
838 tx_skb->data[0] = (__u8) (n & 0x7f);
839
840 irlmp_data_request(self->lsap, tx_skb);
841 self->stats.tx_packets++;
842 }
843
844 /*
845 * Function irttp_udata_indication (instance, sap, skb)
846 *
847 * Received some unit-data (unreliable)
848 *
849 */
850 static int irttp_udata_indication(void *instance, void *sap,
851 struct sk_buff *skb)
852 {
853 struct tsap_cb *self;
854 int err;
855
856 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
857
858 self = (struct tsap_cb *) instance;
859
860 ASSERT(self != NULL, return -1;);
861 ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
862 ASSERT(skb != NULL, return -1;);
863
864 self->stats.rx_packets++;
865
866 /* Just pass data to layer above */
867 if (self->notify.udata_indication) {
868 err = self->notify.udata_indication(self->notify.instance,
869 self,skb);
870 /* Same comment as in irttp_do_data_indication() */
871 if (!err)
872 return 0;
873 }
874 /* Either no handler, or handler returns an error */
875 dev_kfree_skb(skb);
876
877 return 0;
878 }
879
880 /*
881 * Function irttp_data_indication (instance, sap, skb)
882 *
883 * Receive segment from IrLMP.
884 *
885 */
886 static int irttp_data_indication(void *instance, void *sap,
887 struct sk_buff *skb)
888 {
889 struct tsap_cb *self;
890 unsigned long flags;
891 int n;
892
893 self = (struct tsap_cb *) instance;
894
895 n = skb->data[0] & 0x7f; /* Extract the credits */
896
897 self->stats.rx_packets++;
898
899 /* Deal with inbound credit
900 * Since we can transmit and receive frames concurrently,
901 * the code below is a critical region and we must assure that
902 * nobody messes with the credits while we update them.
903 */
904 spin_lock_irqsave(&self->lock, flags);
905 self->send_credit += n;
906 if (skb->len > 1)
907 self->remote_credit--;
908 spin_unlock_irqrestore(&self->lock, flags);
909
910 /*
911 * Data or dataless packet? Dataless frames contains only the
912 * TTP_HEADER.
913 */
914 if (skb->len > 1) {
915 /*
916 * We don't remove the TTP header, since we must preserve the
917 * more bit, so the defragment routing knows what to do
918 */
919 skb_queue_tail(&self->rx_queue, skb);
920 } else {
921 /* Dataless flowdata TTP-PDU */
922 dev_kfree_skb(skb);
923 }
924
925
926 /* Push data to the higher layer.
927 * We do it synchronously because running the todo timer for each
928 * receive packet would be too much overhead and latency.
929 * By passing control to the higher layer, we run the risk that
930 * it may take time or grab a lock. Most often, the higher layer
931 * will only put packet in a queue.
932 * Anyway, packets are only dripping through the IrDA, so we can
933 * have time before the next packet.
934 * Further, we are run from NET_BH, so the worse that can happen is
935 * us missing the optimal time to send back the PF bit in LAP.
936 * Jean II */
937 irttp_run_rx_queue(self);
938
939 /* We now give credits to peer in irttp_run_rx_queue().
940 * We need to send credit *NOW*, otherwise we are going
941 * to miss the next Tx window. The todo timer may take
942 * a while before it's run... - Jean II */
943
944 /*
945 * If the peer device has given us some credits and we didn't have
946 * anyone from before, then we need to shedule the tx queue.
947 * We need to do that because our Tx have stopped (so we may not
948 * get any LAP flow indication) and the user may be stopped as
949 * well. - Jean II
950 */
951 if (self->send_credit == n) {
952 /* Restart pushing stuff to LAP */
953 irttp_run_tx_queue(self);
954 /* Note : we don't want to schedule the todo timer
955 * because it has horrible latency. No tasklets
956 * because the tasklet API is broken. - Jean II */
957 }
958
959 return 0;
960 }
961
962 /*
963 * Function irttp_status_indication (self, reason)
964 *
965 * Status_indication, just pass to the higher layer...
966 *
967 */
968 static void irttp_status_indication(void *instance,
969 LINK_STATUS link, LOCK_STATUS lock)
970 {
971 struct tsap_cb *self;
972
973 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
974
975 self = (struct tsap_cb *) instance;
976
977 ASSERT(self != NULL, return;);
978 ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
979
980 /* Check if client has already closed the TSAP and gone away */
981 if (self->close_pend)
982 return;
983
984 /*
985 * Inform service user if he has requested it
986 */
987 if (self->notify.status_indication != NULL)
988 self->notify.status_indication(self->notify.instance,
989 link, lock);
990 else
991 IRDA_DEBUG(2, "%s(), no handler\n", __FUNCTION__);
992 }
993
994 /*
995 * Function irttp_flow_indication (self, reason)
996 *
997 * Flow_indication : IrLAP tells us to send more data.
998 *
999 */
1000 static void irttp_flow_indication(void *instance, void *sap, LOCAL_FLOW flow)
1001 {
1002 struct tsap_cb *self;
1003
1004 self = (struct tsap_cb *) instance;
1005
1006 ASSERT(self != NULL, return;);
1007 ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1008
1009 IRDA_DEBUG(4, "%s(instance=%p)\n", __FUNCTION__, self);
1010
1011 /* We are "polled" directly from LAP, and the LAP want to fill
1012 * its Tx window. We want to do our best to send it data, so that
1013 * we maximise the window. On the other hand, we want to limit the
1014 * amount of work here so that LAP doesn't hang forever waiting
1015 * for packets. - Jean II */
1016
1017 /* Try to send some packets. Currently, LAP calls us every time
1018 * there is one free slot, so we will send only one packet.
1019 * This allow the scheduler to do its round robin - Jean II */
1020 irttp_run_tx_queue(self);
1021
1022 /* Note regarding the interraction with higher layer.
1023 * irttp_run_tx_queue() may call the client when its queue
1024 * start to empty, via notify.flow_indication(). Initially.
1025 * I wanted this to happen in a tasklet, to avoid client
1026 * grabbing the CPU, but we can't use tasklets safely. And timer
1027 * is definitely too slow.
1028 * This will happen only once per LAP window, and usually at
1029 * the third packet (unless window is smaller). LAP is still
1030 * doing mtt and sending first packet so it's sort of OK
1031 * to do that. Jean II */
1032
1033 /* If we need to send disconnect. try to do it now */
1034 if(self->disconnect_pend)
1035 irttp_start_todo_timer(self, 0);
1036 }
1037
1038 /*
1039 * Function irttp_flow_request (self, command)
1040 *
1041 * This function could be used by the upper layers to tell IrTTP to stop
1042 * delivering frames if the receive queues are starting to get full, or
1043 * to tell IrTTP to start delivering frames again.
1044 */
1045 void irttp_flow_request(struct tsap_cb *self, LOCAL_FLOW flow)
1046 {
1047 IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
1048
1049 ASSERT(self != NULL, return;);
1050 ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1051
1052 switch (flow) {
1053 case FLOW_STOP:
1054 IRDA_DEBUG(1, "%s(), flow stop\n", __FUNCTION__);
1055 self->rx_sdu_busy = TRUE;
1056 break;
1057 case FLOW_START:
1058 IRDA_DEBUG(1, "%s(), flow start\n", __FUNCTION__);
1059 self->rx_sdu_busy = FALSE;
1060
1061 /* Client say he can accept more data, try to free our
1062 * queues ASAP - Jean II */
1063 irttp_run_rx_queue(self);
1064
1065 break;
1066 default:
1067 IRDA_DEBUG(1, "%s(), Unknown flow command!\n", __FUNCTION__);
1068 }
1069 }
1070 EXPORT_SYMBOL(irttp_flow_request);
1071
1072 /*
1073 * Function irttp_connect_request (self, dtsap_sel, daddr, qos)
1074 *
1075 * Try to connect to remote destination TSAP selector
1076 *
1077 */
1078 int irttp_connect_request(struct tsap_cb *self, __u8 dtsap_sel,
1079 __u32 saddr, __u32 daddr,
1080 struct qos_info *qos, __u32 max_sdu_size,
1081 struct sk_buff *userdata)
1082 {
1083 struct sk_buff *tx_skb;
1084 __u8 *frame;
1085 __u8 n;
1086
1087 IRDA_DEBUG(4, "%s(), max_sdu_size=%d\n", __FUNCTION__, max_sdu_size);
1088
1089 ASSERT(self != NULL, return -EBADR;);
1090 ASSERT(self->magic == TTP_TSAP_MAGIC, return -EBADR;);
1091
1092 if (self->connected) {
1093 if(userdata)
1094 dev_kfree_skb(userdata);
1095 return -EISCONN;
1096 }
1097
1098 /* Any userdata supplied? */
1099 if (userdata == NULL) {
1100 tx_skb = dev_alloc_skb(64);
1101 if (!tx_skb)
1102 return -ENOMEM;
1103
1104 /* Reserve space for MUX_CONTROL and LAP header */
1105 skb_reserve(tx_skb, TTP_MAX_HEADER);
1106 } else {
1107 tx_skb = userdata;
1108 /*
1109 * Check that the client has reserved enough space for
1110 * headers
1111 */
1112 ASSERT(skb_headroom(userdata) >= TTP_MAX_HEADER,
1113 { dev_kfree_skb(userdata); return -1; } );
1114 }
1115
1116 /* Initialize connection parameters */
1117 self->connected = FALSE;
1118 self->avail_credit = 0;
1119 self->rx_max_sdu_size = max_sdu_size;
1120 self->rx_sdu_size = 0;
1121 self->rx_sdu_busy = FALSE;
1122 self->dtsap_sel = dtsap_sel;
1123
1124 n = self->initial_credit;
1125
1126 self->remote_credit = 0;
1127 self->send_credit = 0;
1128
1129 /*
1130 * Give away max 127 credits for now
1131 */
1132 if (n > 127) {
1133 self->avail_credit=n-127;
1134 n = 127;
1135 }
1136
1137 self->remote_credit = n;
1138
1139 /* SAR enabled? */
1140 if (max_sdu_size > 0) {
1141 ASSERT(skb_headroom(tx_skb) >= (TTP_MAX_HEADER + TTP_SAR_HEADER),
1142 { dev_kfree_skb(tx_skb); return -1; } );
1143
1144 /* Insert SAR parameters */
1145 frame = skb_push(tx_skb, TTP_HEADER+TTP_SAR_HEADER);
1146
1147 frame[0] = TTP_PARAMETERS | n;
1148 frame[1] = 0x04; /* Length */
1149 frame[2] = 0x01; /* MaxSduSize */
1150 frame[3] = 0x02; /* Value length */
1151
1152 put_unaligned(cpu_to_be16((__u16) max_sdu_size),
1153 (__u16 *)(frame+4));
1154 } else {
1155 /* Insert plain TTP header */
1156 frame = skb_push(tx_skb, TTP_HEADER);
1157
1158 /* Insert initial credit in frame */
1159 frame[0] = n & 0x7f;
1160 }
1161
1162 /* Connect with IrLMP. No QoS parameters for now */
1163 return irlmp_connect_request(self->lsap, dtsap_sel, saddr, daddr, qos,
1164 tx_skb);
1165 }
1166 EXPORT_SYMBOL(irttp_connect_request);
1167
1168 /*
1169 * Function irttp_connect_confirm (handle, qos, skb)
1170 *
1171 * Sevice user confirms TSAP connection with peer.
1172 *
1173 */
1174 static void irttp_connect_confirm(void *instance, void *sap,
1175 struct qos_info *qos, __u32 max_seg_size,
1176 __u8 max_header_size, struct sk_buff *skb)
1177 {
1178 struct tsap_cb *self;
1179 int parameters;
1180 int ret;
1181 __u8 plen;
1182 __u8 n;
1183
1184 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
1185
1186 self = (struct tsap_cb *) instance;
1187
1188 ASSERT(self != NULL, return;);
1189 ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1190 ASSERT(skb != NULL, return;);
1191
1192 self->max_seg_size = max_seg_size - TTP_HEADER;
1193 self->max_header_size = max_header_size + TTP_HEADER;
1194
1195 /*
1196 * Check if we have got some QoS parameters back! This should be the
1197 * negotiated QoS for the link.
1198 */
1199 if (qos) {
1200 IRDA_DEBUG(4, "IrTTP, Negotiated BAUD_RATE: %02x\n",
1201 qos->baud_rate.bits);
1202 IRDA_DEBUG(4, "IrTTP, Negotiated BAUD_RATE: %d bps.\n",
1203 qos->baud_rate.value);
1204 }
1205
1206 n = skb->data[0] & 0x7f;
1207
1208 IRDA_DEBUG(4, "%s(), Initial send_credit=%d\n", __FUNCTION__, n);
1209
1210 self->send_credit = n;
1211 self->tx_max_sdu_size = 0;
1212 self->connected = TRUE;
1213
1214 parameters = skb->data[0] & 0x80;
1215
1216 ASSERT(skb->len >= TTP_HEADER, return;);
1217 skb_pull(skb, TTP_HEADER);
1218
1219 if (parameters) {
1220 plen = skb->data[0];
1221
1222 ret = irda_param_extract_all(self, skb->data+1,
1223 IRDA_MIN(skb->len-1, plen),
1224 ¶m_info);
1225
1226 /* Any errors in the parameter list? */
1227 if (ret < 0) {
1228 WARNING("%s: error extracting parameters\n",
1229 __FUNCTION__);
1230 dev_kfree_skb(skb);
1231
1232 /* Do not accept this connection attempt */
1233 return;
1234 }
1235 /* Remove parameters */
1236 skb_pull(skb, IRDA_MIN(skb->len, plen+1));
1237 }
1238
1239 IRDA_DEBUG(4, "%s() send=%d,avail=%d,remote=%d\n", __FUNCTION__,
1240 self->send_credit, self->avail_credit, self->remote_credit);
1241
1242 IRDA_DEBUG(2, "%s(), MaxSduSize=%d\n", __FUNCTION__,
1243 self->tx_max_sdu_size);
1244
1245 if (self->notify.connect_confirm) {
1246 self->notify.connect_confirm(self->notify.instance, self, qos,
1247 self->tx_max_sdu_size,
1248 self->max_header_size, skb);
1249 } else
1250 dev_kfree_skb(skb);
1251 }
1252
1253 /*
1254 * Function irttp_connect_indication (handle, skb)
1255 *
1256 * Some other device is connecting to this TSAP
1257 *
1258 */
1259 void irttp_connect_indication(void *instance, void *sap, struct qos_info *qos,
1260 __u32 max_seg_size, __u8 max_header_size,
1261 struct sk_buff *skb)
1262 {
1263 struct tsap_cb *self;
1264 struct lsap_cb *lsap;
1265 int parameters;
1266 int ret;
1267 __u8 plen;
1268 __u8 n;
1269
1270 self = (struct tsap_cb *) instance;
1271
1272 ASSERT(self != NULL, return;);
1273 ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1274 ASSERT(skb != NULL, return;);
1275
1276 lsap = (struct lsap_cb *) sap;
1277
1278 self->max_seg_size = max_seg_size - TTP_HEADER;
1279 self->max_header_size = max_header_size+TTP_HEADER;
1280
1281 IRDA_DEBUG(4, "%s(), TSAP sel=%02x\n", __FUNCTION__, self->stsap_sel);
1282
1283 /* Need to update dtsap_sel if its equal to LSAP_ANY */
1284 self->dtsap_sel = lsap->dlsap_sel;
1285
1286 n = skb->data[0] & 0x7f;
1287
1288 self->send_credit = n;
1289 self->tx_max_sdu_size = 0;
1290
1291 parameters = skb->data[0] & 0x80;
1292
1293 ASSERT(skb->len >= TTP_HEADER, return;);
1294 skb_pull(skb, TTP_HEADER);
1295
1296 if (parameters) {
1297 plen = skb->data[0];
1298
1299 ret = irda_param_extract_all(self, skb->data+1,
1300 IRDA_MIN(skb->len-1, plen),
1301 ¶m_info);
1302
1303 /* Any errors in the parameter list? */
1304 if (ret < 0) {
1305 WARNING("%s: error extracting parameters\n",
1306 __FUNCTION__);
1307 dev_kfree_skb(skb);
1308
1309 /* Do not accept this connection attempt */
1310 return;
1311 }
1312
1313 /* Remove parameters */
1314 skb_pull(skb, IRDA_MIN(skb->len, plen+1));
1315 }
1316
1317 if (self->notify.connect_indication) {
1318 self->notify.connect_indication(self->notify.instance, self,
1319 qos, self->tx_max_sdu_size,
1320 self->max_header_size, skb);
1321 } else
1322 dev_kfree_skb(skb);
1323 }
1324
1325 /*
1326 * Function irttp_connect_response (handle, userdata)
1327 *
1328 * Service user is accepting the connection, just pass it down to
1329 * IrLMP!
1330 *
1331 */
1332 int irttp_connect_response(struct tsap_cb *self, __u32 max_sdu_size,
1333 struct sk_buff *userdata)
1334 {
1335 struct sk_buff *tx_skb;
1336 __u8 *frame;
1337 int ret;
1338 __u8 n;
1339
1340 ASSERT(self != NULL, return -1;);
1341 ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
1342
1343 IRDA_DEBUG(4, "%s(), Source TSAP selector=%02x\n", __FUNCTION__,
1344 self->stsap_sel);
1345
1346 /* Any userdata supplied? */
1347 if (userdata == NULL) {
1348 tx_skb = dev_alloc_skb(64);
1349 if (!tx_skb)
1350 return -ENOMEM;
1351
1352 /* Reserve space for MUX_CONTROL and LAP header */
1353 skb_reserve(tx_skb, TTP_MAX_HEADER);
1354 } else {
1355 tx_skb = userdata;
1356 /*
1357 * Check that the client has reserved enough space for
1358 * headers
1359 */
1360 ASSERT(skb_headroom(userdata) >= TTP_MAX_HEADER,
1361 { dev_kfree_skb(userdata); return -1; } );
1362 }
1363
1364 self->avail_credit = 0;
1365 self->remote_credit = 0;
1366 self->rx_max_sdu_size = max_sdu_size;
1367 self->rx_sdu_size = 0;
1368 self->rx_sdu_busy = FALSE;
1369
1370 n = self->initial_credit;
1371
1372 /* Frame has only space for max 127 credits (7 bits) */
1373 if (n > 127) {
1374 self->avail_credit = n - 127;
1375 n = 127;
1376 }
1377
1378 self->remote_credit = n;
1379 self->connected = TRUE;
1380
1381 /* SAR enabled? */
1382 if (max_sdu_size > 0) {
1383 ASSERT(skb_headroom(tx_skb) >= (TTP_MAX_HEADER + TTP_SAR_HEADER),
1384 { dev_kfree_skb(tx_skb); return -1; } );
1385
1386 /* Insert TTP header with SAR parameters */
1387 frame = skb_push(tx_skb, TTP_HEADER+TTP_SAR_HEADER);
1388
1389 frame[0] = TTP_PARAMETERS | n;
1390 frame[1] = 0x04; /* Length */
1391
1392 /* irda_param_insert(self, IRTTP_MAX_SDU_SIZE, frame+1, */
1393 /* TTP_SAR_HEADER, ¶m_info) */
1394
1395 frame[2] = 0x01; /* MaxSduSize */
1396 frame[3] = 0x02; /* Value length */
1397
1398 put_unaligned(cpu_to_be16((__u16) max_sdu_size),
1399 (__u16 *)(frame+4));
1400 } else {
1401 /* Insert TTP header */
1402 frame = skb_push(tx_skb, TTP_HEADER);
1403
1404 frame[0] = n & 0x7f;
1405 }
1406
1407 ret = irlmp_connect_response(self->lsap, tx_skb);
1408
1409 return ret;
1410 }
1411 EXPORT_SYMBOL(irttp_connect_response);
1412
1413 /*
1414 * Function irttp_dup (self, instance)
1415 *
1416 * Duplicate TSAP, can be used by servers to confirm a connection on a
1417 * new TSAP so it can keep listening on the old one.
1418 */
1419 struct tsap_cb *irttp_dup(struct tsap_cb *orig, void *instance)
1420 {
1421 struct tsap_cb *new;
1422 unsigned long flags;
1423
1424 IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
1425
1426 /* Protect our access to the old tsap instance */
1427 spin_lock_irqsave(&irttp->tsaps->hb_spinlock, flags);
1428
1429 /* Find the old instance */
1430 if (!hashbin_find(irttp->tsaps, (long) orig, NULL)) {
1431 IRDA_DEBUG(0, "%s(), unable to find TSAP\n", __FUNCTION__);
1432 spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
1433 return NULL;
1434 }
1435
1436 /* Allocate a new instance */
1437 new = kmalloc(sizeof(struct tsap_cb), GFP_ATOMIC);
1438 if (!new) {
1439 IRDA_DEBUG(0, "%s(), unable to kmalloc\n", __FUNCTION__);
1440 spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
1441 return NULL;
1442 }
1443 /* Dup */
1444 memcpy(new, orig, sizeof(struct tsap_cb));
1445
1446 /* We don't need the old instance any more */
1447 spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
1448
1449 /* Try to dup the LSAP (may fail if we were too slow) */
1450 new->lsap = irlmp_dup(orig->lsap, new);
1451 if (!new->lsap) {
1452 IRDA_DEBUG(0, "%s(), dup failed!\n", __FUNCTION__);
1453 kfree(new);
1454 return NULL;
1455 }
1456
1457 /* Not everything should be copied */
1458 new->notify.instance = instance;
1459 init_timer(&new->todo_timer);
1460
1461 skb_queue_head_init(&new->rx_queue);
1462 skb_queue_head_init(&new->tx_queue);
1463 skb_queue_head_init(&new->rx_fragments);
1464
1465 /* This is locked */
1466 hashbin_insert(irttp->tsaps, (irda_queue_t *) new, (long) new, NULL);
1467
1468 return new;
1469 }
1470 EXPORT_SYMBOL(irttp_dup);
1471
1472 /*
1473 * Function irttp_disconnect_request (self)
1474 *
1475 * Close this connection please! If priority is high, the queued data
1476 * segments, if any, will be deallocated first
1477 *
1478 */
1479 int irttp_disconnect_request(struct tsap_cb *self, struct sk_buff *userdata,
1480 int priority)
1481 {
1482 int ret;
1483
1484 ASSERT(self != NULL, return -1;);
1485 ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
1486
1487 /* Already disconnected? */
1488 if (!self->connected) {
1489 IRDA_DEBUG(4, "%s(), already disconnected!\n", __FUNCTION__);
1490 if (userdata)
1491 dev_kfree_skb(userdata);
1492 return -1;
1493 }
1494
1495 /* Disconnect already pending ?
1496 * We need to use an atomic operation to prevent reentry. This
1497 * function may be called from various context, like user, timer
1498 * for following a disconnect_indication() (i.e. net_bh).
1499 * Jean II */
1500 if(test_and_set_bit(0, &self->disconnect_pend)) {
1501 IRDA_DEBUG(0, "%s(), disconnect already pending\n",
1502 __FUNCTION__);
1503 if (userdata)
1504 dev_kfree_skb(userdata);
1505
1506 /* Try to make some progress */
1507 irttp_run_tx_queue(self);
1508 return -1;
1509 }
1510
1511 /*
1512 * Check if there is still data segments in the transmit queue
1513 */
1514 if (skb_queue_len(&self->tx_queue) > 0) {
1515 if (priority == P_HIGH) {
1516 /*
1517 * No need to send the queued data, if we are
1518 * disconnecting right now since the data will
1519 * not have any usable connection to be sent on
1520 */
1521 IRDA_DEBUG(1, "%s(): High priority!!()\n", __FUNCTION__);
1522 irttp_flush_queues(self);
1523 } else if (priority == P_NORMAL) {
1524 /*
1525 * Must delay disconnect until after all data segments
1526 * have been sent and the tx_queue is empty
1527 */
1528 /* We'll reuse this one later for the disconnect */
1529 self->disconnect_skb = userdata; /* May be NULL */
1530
1531 irttp_run_tx_queue(self);
1532
1533 irttp_start_todo_timer(self, HZ/10);
1534 return -1;
1535 }
1536 }
1537 /* Note : we don't need to check if self->rx_queue is full and the
1538 * state of self->rx_sdu_busy because the disconnect response will
1539 * be sent at the LMP level (so even if the peer has its Tx queue
1540 * full of data). - Jean II */
1541
1542 IRDA_DEBUG(1, "%s(), Disconnecting ...\n", __FUNCTION__);
1543 self->connected = FALSE;
1544
1545 if (!userdata) {
1546 struct sk_buff *tx_skb;
1547 tx_skb = dev_alloc_skb(64);
1548 if (!tx_skb)
1549 return -ENOMEM;
1550
1551 /*
1552 * Reserve space for MUX and LAP header
1553 */
1554 skb_reserve(tx_skb, TTP_MAX_HEADER);
1555
1556 userdata = tx_skb;
1557 }
1558 ret = irlmp_disconnect_request(self->lsap, userdata);
1559
1560 /* The disconnect is no longer pending */
1561 clear_bit(0, &self->disconnect_pend); /* FALSE */
1562
1563 return ret;
1564 }
1565 EXPORT_SYMBOL(irttp_disconnect_request);
1566
1567 /*
1568 * Function irttp_disconnect_indication (self, reason)
1569 *
1570 * Disconnect indication, TSAP disconnected by peer?
1571 *
1572 */
1573 void irttp_disconnect_indication(void *instance, void *sap, LM_REASON reason,
1574 struct sk_buff *skb)
1575 {
1576 struct tsap_cb *self;
1577
1578 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
1579
1580 self = (struct tsap_cb *) instance;
1581
1582 ASSERT(self != NULL, return;);
1583 ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1584
1585 /* Prevent higher layer to send more data */
1586 self->connected = FALSE;
1587
1588 /* Check if client has already tried to close the TSAP */
1589 if (self->close_pend) {
1590 /* In this case, the higher layer is probably gone. Don't
1591 * bother it and clean up the remains - Jean II */
1592 if (skb)
1593 dev_kfree_skb(skb);
1594 irttp_close_tsap(self);
1595 return;
1596 }
1597
1598 /* If we are here, we assume that is the higher layer is still
1599 * waiting for the disconnect notification and able to process it,
1600 * even if he tried to disconnect. Otherwise, it would have already
1601 * attempted to close the tsap and self->close_pend would be TRUE.
1602 * Jean II */
1603
1604 /* No need to notify the client if has already tried to disconnect */
1605 if(self->notify.disconnect_indication)
1606 self->notify.disconnect_indication(self->notify.instance, self,
1607 reason, skb);
1608 else
1609 if (skb)
1610 dev_kfree_skb(skb);
1611 }
1612
1613 /*
1614 * Function irttp_do_data_indication (self, skb)
1615 *
1616 * Try to deliver reassembled skb to layer above, and requeue it if that
1617 * for some reason should fail. We mark rx sdu as busy to apply back
1618 * pressure is necessary.
1619 */
1620 static void irttp_do_data_indication(struct tsap_cb *self, struct sk_buff *skb)
1621 {
1622 int err;
1623
1624 /* Check if client has already closed the TSAP and gone away */
1625 if (self->close_pend) {
1626 dev_kfree_skb(skb);
1627 return;
1628 }
1629
1630 err = self->notify.data_indication(self->notify.instance, self, skb);
1631
1632 /* Usually the layer above will notify that it's input queue is
1633 * starting to get filled by using the flow request, but this may
1634 * be difficult, so it can instead just refuse to eat it and just
1635 * give an error back
1636 */
1637 if (err) {
1638 IRDA_DEBUG(0, "%s() requeueing skb!\n", __FUNCTION__);
1639
1640 /* Make sure we take a break */
1641 self->rx_sdu_busy = TRUE;
1642
1643 /* Need to push the header in again */
1644 skb_push(skb, TTP_HEADER);
1645 skb->data[0] = 0x00; /* Make sure MORE bit is cleared */
1646
1647 /* Put skb back on queue */
1648 skb_queue_head(&self->rx_queue, skb);
1649 }
1650 }
1651
1652 /*
1653 * Function irttp_run_rx_queue (self)
1654 *
1655 * Check if we have any frames to be transmitted, or if we have any
1656 * available credit to give away.
1657 */
1658 void irttp_run_rx_queue(struct tsap_cb *self)
1659 {
1660 struct sk_buff *skb;
1661 int more = 0;
1662
1663 IRDA_DEBUG(2, "%s() send=%d,avail=%d,remote=%d\n", __FUNCTION__,
1664 self->send_credit, self->avail_credit, self->remote_credit);
1665
1666 /* Get exclusive access to the rx queue, otherwise don't touch it */
1667 if (irda_lock(&self->rx_queue_lock) == FALSE)
1668 return;
1669
1670 /*
1671 * Reassemble all frames in receive queue and deliver them
1672 */
1673 while (!self->rx_sdu_busy && (skb = skb_dequeue(&self->rx_queue))) {
1674 /* This bit will tell us if it's the last fragment or not */
1675 more = skb->data[0] & 0x80;
1676
1677 /* Remove TTP header */
1678 skb_pull(skb, TTP_HEADER);
1679
1680 /* Add the length of the remaining data */
1681 self->rx_sdu_size += skb->len;
1682
1683 /*
1684 * If SAR is disabled, or user has requested no reassembly
1685 * of received fragments then we just deliver them
1686 * immediately. This can be requested by clients that
1687 * implements byte streams without any message boundaries
1688 */
1689 if (self->rx_max_sdu_size == TTP_SAR_DISABLE) {
1690 irttp_do_data_indication(self, skb);
1691 self->rx_sdu_size = 0;
1692
1693 continue;
1694 }
1695
1696 /* Check if this is a fragment, and not the last fragment */
1697 if (more) {
1698 /*
1699 * Queue the fragment if we still are within the
1700 * limits of the maximum size of the rx_sdu
1701 */
1702 if (self->rx_sdu_size <= self->rx_max_sdu_size) {
1703 IRDA_DEBUG(4, "%s(), queueing frag\n",
1704 __FUNCTION__);
1705 skb_queue_tail(&self->rx_fragments, skb);
1706 } else {
1707 /* Free the part of the SDU that is too big */
1708 dev_kfree_skb(skb);
1709 }
1710 continue;
1711 }
1712 /*
1713 * This is the last fragment, so time to reassemble!
1714 */
1715 if ((self->rx_sdu_size <= self->rx_max_sdu_size) ||
1716 (self->rx_max_sdu_size == TTP_SAR_UNBOUND))
1717 {
1718 /*
1719 * A little optimizing. Only queue the fragment if
1720 * there are other fragments. Since if this is the
1721 * last and only fragment, there is no need to
1722 * reassemble :-)
1723 */
1724 if (!skb_queue_empty(&self->rx_fragments)) {
1725 skb_queue_tail(&self->rx_fragments,
1726 skb);
1727
1728 skb = irttp_reassemble_skb(self);
1729 }
1730
1731 /* Now we can deliver the reassembled skb */
1732 irttp_do_data_indication(self, skb);
1733 } else {
1734 IRDA_DEBUG(1, "%s(), Truncated frame\n", __FUNCTION__);
1735
1736 /* Free the part of the SDU that is too big */
1737 dev_kfree_skb(skb);
1738
1739 /* Deliver only the valid but truncated part of SDU */
1740 skb = irttp_reassemble_skb(self);
1741
1742 irttp_do_data_indication(self, skb);
1743 }
1744 self->rx_sdu_size = 0;
1745 }
1746
1747 /*
1748 * It's not trivial to keep track of how many credits are available
1749 * by incrementing at each packet, because delivery may fail
1750 * (irttp_do_data_indication() may requeue the frame) and because
1751 * we need to take care of fragmentation.
1752 * We want the other side to send up to initial_credit packets.
1753 * We have some frames in our queues, and we have already allowed it
1754 * to send remote_credit.
1755 * No need to spinlock, write is atomic and self correcting...
1756 * Jean II
1757 */
1758 self->avail_credit = (self->initial_credit -
1759 (self->remote_credit +
1760 skb_queue_len(&self->rx_queue) +
1761 skb_queue_len(&self->rx_fragments)));
1762
1763 /* Do we have too much credits to send to peer ? */
1764 if ((self->remote_credit <= TTP_RX_MIN_CREDIT) &&
1765 (self->avail_credit > 0)) {
1766 /* Send explicit credit frame */
1767 irttp_give_credit(self);
1768 /* Note : do *NOT* check if tx_queue is non-empty, that
1769 * will produce deadlocks. I repeat : send a credit frame
1770 * even if we have something to send in our Tx queue.
1771 * If we have credits, it means that our Tx queue is blocked.
1772 *
1773 * Let's suppose the peer can't keep up with our Tx. He will
1774 * flow control us by not sending us any credits, and we
1775 * will stop Tx and start accumulating credits here.
1776 * Up to the point where the peer will stop its Tx queue,
1777 * for lack of credits.
1778 * Let's assume the peer application is single threaded.
1779 * It will block on Tx and never consume any Rx buffer.
1780 * Deadlock. Guaranteed. - Jean II
1781 */
1782 }
1783
1784 /* Reset lock */
1785 self->rx_queue_lock = 0;
1786 }
1787
1788 #ifdef CONFIG_PROC_FS
1789 struct irttp_iter_state {
1790 int id;
1791 };
1792
1793 static void *irttp_seq_start(struct seq_file *seq, loff_t *pos)
1794 {
1795 struct irttp_iter_state *iter = seq->private;
1796 struct tsap_cb *self;
1797
1798 /* Protect our access to the tsap list */
1799 spin_lock_irq(&irttp->tsaps->hb_spinlock);
1800 iter->id = 0;
1801
1802 for (self = (struct tsap_cb *) hashbin_get_first(irttp->tsaps);
1803 self != NULL;
1804 self = (struct tsap_cb *) hashbin_get_next(irttp->tsaps)) {
1805 if (iter->id == *pos)
1806 break;
1807 ++iter->id;
1808 }
1809
1810 return self;
1811 }
1812
1813 static void *irttp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1814 {
1815 struct irttp_iter_state *iter = seq->private;
1816
1817 ++*pos;
1818 ++iter->id;
1819 return (void *) hashbin_get_next(irttp->tsaps);
1820 }
1821
1822 static void irttp_seq_stop(struct seq_file *seq, void *v)
1823 {
1824 spin_unlock_irq(&irttp->tsaps->hb_spinlock);
1825 }
1826
1827 static int irttp_seq_show(struct seq_file *seq, void *v)
1828 {
1829 const struct irttp_iter_state *iter = seq->private;
1830 const struct tsap_cb *self = v;
1831
1832 seq_printf(seq, "TSAP %d, ", iter->id);
1833 seq_printf(seq, "stsap_sel: %02x, ",
1834 self->stsap_sel);
1835 seq_printf(seq, "dtsap_sel: %02x\n",
1836 self->dtsap_sel);
1837 seq_printf(seq, " connected: %s, ",
1838 self->connected? "TRUE":"FALSE");
1839 seq_printf(seq, "avail credit: %d, ",
1840 self->avail_credit);
1841 seq_printf(seq, "remote credit: %d, ",
1842 self->remote_credit);
1843 seq_printf(seq, "send credit: %d\n",
1844 self->send_credit);
1845 seq_printf(seq, " tx packets: %ld, ",
1846 self->stats.tx_packets);
1847 seq_printf(seq, "rx packets: %ld, ",
1848 self->stats.rx_packets);
1849 seq_printf(seq, "tx_queue len: %d ",
1850 skb_queue_len(&self->tx_queue));
1851 seq_printf(seq, "rx_queue len: %d\n",
1852 skb_queue_len(&self->rx_queue));
1853 seq_printf(seq, " tx_sdu_busy: %s, ",
1854 self->tx_sdu_busy? "TRUE":"FALSE");
1855 seq_printf(seq, "rx_sdu_busy: %s\n",
1856 self->rx_sdu_busy? "TRUE":"FALSE");
1857 seq_printf(seq, " max_seg_size: %d, ",
1858 self->max_seg_size);
1859 seq_printf(seq, "tx_max_sdu_size: %d, ",
1860 self->tx_max_sdu_size);
1861 seq_printf(seq, "rx_max_sdu_size: %d\n",
1862 self->rx_max_sdu_size);
1863
1864 seq_printf(seq, " Used by (%s)\n\n",
1865 self->notify.name);
1866 return 0;
1867 }
1868
1869 static struct seq_operations irttp_seq_ops = {
1870 .start = irttp_seq_start,
1871 .next = irttp_seq_next,
1872 .stop = irttp_seq_stop,
1873 .show = irttp_seq_show,
1874 };
1875
1876 static int irttp_seq_open(struct inode *inode, struct file *file)
1877 {
1878 struct seq_file *seq;
1879 int rc = -ENOMEM;
1880 struct irttp_iter_state *s;
1881
1882 ASSERT(irttp != NULL, return -EINVAL;);
1883
1884 s = kmalloc(sizeof(*s), GFP_KERNEL);
1885 if (!s)
1886 goto out;
1887
1888 rc = seq_open(file, &irttp_seq_ops);
1889 if (rc)
1890 goto out_kfree;
1891
1892 seq = file->private_data;
1893 seq->private = s;
1894 memset(s, 0, sizeof(*s));
1895 out:
1896 return rc;
1897 out_kfree:
1898 kfree(s);
1899 goto out;
1900 }
1901
1902 struct file_operations irttp_seq_fops = {
1903 .owner = THIS_MODULE,
1904 .open = irttp_seq_open,
1905 .read = seq_read,
1906 .llseek = seq_lseek,
1907 .release = seq_release_private,
1908 };
1909
1910 #endif /* PROC_FS */
1911
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