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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*********************************************************************
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 Tromsø 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
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <linux/skbuff.h>
28#include <linux/init.h>
Al Virod7fe0f22006-12-03 23:15:30 -050029#include <linux/fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#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
Alexey Dobriyan8689c072005-09-24 16:55:17 -070041static struct irttp_cb *irttp;
Linus Torvalds1da177e2005-04-16 15:20:36 -070042
43static void __irttp_close_tsap(struct tsap_cb *self);
44
45static int irttp_data_indication(void *instance, void *sap,
46 struct sk_buff *skb);
47static int irttp_udata_indication(void *instance, void *sap,
48 struct sk_buff *skb);
49static void irttp_disconnect_indication(void *instance, void *sap,
50 LM_REASON reason, struct sk_buff *);
51static 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);
54static 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);
57static void irttp_run_tx_queue(struct tsap_cb *self);
58static void irttp_run_rx_queue(struct tsap_cb *self);
59
60static void irttp_flush_queues(struct tsap_cb *self);
61static void irttp_fragment_skb(struct tsap_cb *self, struct sk_buff *skb);
62static struct sk_buff *irttp_reassemble_skb(struct tsap_cb *self);
63static void irttp_todo_expired(unsigned long data);
64static int irttp_param_max_sdu_size(void *instance, irda_param_t *param,
65 int get);
66
67static void irttp_flow_indication(void *instance, void *sap, LOCAL_FLOW flow);
68static void irttp_status_indication(void *instance,
69 LINK_STATUS link, LOCK_STATUS lock);
70
71/* Information for parsing parameters in IrTTP */
72static 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};
76static pi_major_info_t pi_major_call_table[] = {{ pi_minor_call_table, 2 }};
77static 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 */
87int __init irttp_init(void)
88{
Panagiotis Issaris0da974f2006-07-21 14:51:30 -070089 irttp = kzalloc(sizeof(struct irttp_cb), GFP_KERNEL);
Alexey Dobriyan8689c072005-09-24 16:55:17 -070090 if (irttp == NULL)
91 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -070092
93 irttp->magic = TTP_MAGIC;
94
95 irttp->tsaps = hashbin_new(HB_LOCK);
96 if (!irttp->tsaps) {
97 IRDA_ERROR("%s: can't allocate IrTTP hashbin!\n",
98 __FUNCTION__);
Alexey Dobriyan15166fadb2005-09-24 16:54:50 -070099 kfree(irttp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 return -ENOMEM;
101 }
102
103 return 0;
104}
105
106/*
107 * Function irttp_cleanup (void)
108 *
109 * Called by module destruction/cleanup code
110 *
111 */
112void __exit irttp_cleanup(void)
113{
114 /* Check for main structure */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 IRDA_ASSERT(irttp->magic == TTP_MAGIC, return;);
116
117 /*
118 * Delete hashbin and close all TSAP instances in it
119 */
120 hashbin_delete(irttp->tsaps, (FREE_FUNC) __irttp_close_tsap);
121
122 irttp->magic = 0;
123
124 /* De-allocate main structure */
125 kfree(irttp);
126
127 irttp = NULL;
128}
129
130/*************************** SUBROUTINES ***************************/
131
132/*
133 * Function irttp_start_todo_timer (self, timeout)
134 *
135 * Start todo timer.
136 *
137 * Made it more effient and unsensitive to race conditions - Jean II
138 */
139static inline void irttp_start_todo_timer(struct tsap_cb *self, int timeout)
140{
141 /* Set new value for timer */
142 mod_timer(&self->todo_timer, jiffies + timeout);
143}
144
145/*
146 * Function irttp_todo_expired (data)
147 *
148 * Todo timer has expired!
149 *
150 * One of the restriction of the timer is that it is run only on the timer
151 * interrupt which run every 10ms. This mean that even if you set the timer
152 * with a delay of 0, it may take up to 10ms before it's run.
153 * So, to minimise latency and keep cache fresh, we try to avoid using
154 * it as much as possible.
155 * Note : we can't use tasklets, because they can't be asynchronously
156 * killed (need user context), and we can't guarantee that here...
157 * Jean II
158 */
159static void irttp_todo_expired(unsigned long data)
160{
161 struct tsap_cb *self = (struct tsap_cb *) data;
162
163 /* Check that we still exist */
164 if (!self || self->magic != TTP_TSAP_MAGIC)
165 return;
166
167 IRDA_DEBUG(4, "%s(instance=%p)\n", __FUNCTION__, self);
168
169 /* Try to make some progress, especially on Tx side - Jean II */
170 irttp_run_rx_queue(self);
171 irttp_run_tx_queue(self);
172
173 /* Check if time for disconnect */
174 if (test_bit(0, &self->disconnect_pend)) {
175 /* Check if it's possible to disconnect yet */
176 if (skb_queue_empty(&self->tx_queue)) {
177 /* Make sure disconnect is not pending anymore */
178 clear_bit(0, &self->disconnect_pend); /* FALSE */
179
180 /* Note : self->disconnect_skb may be NULL */
181 irttp_disconnect_request(self, self->disconnect_skb,
182 P_NORMAL);
183 self->disconnect_skb = NULL;
184 } else {
185 /* Try again later */
186 irttp_start_todo_timer(self, HZ/10);
187
188 /* No reason to try and close now */
189 return;
190 }
191 }
192
193 /* Check if it's closing time */
194 if (self->close_pend)
195 /* Finish cleanup */
196 irttp_close_tsap(self);
197}
198
199/*
200 * Function irttp_flush_queues (self)
201 *
202 * Flushes (removes all frames) in transitt-buffer (tx_list)
203 */
204void irttp_flush_queues(struct tsap_cb *self)
205{
206 struct sk_buff* skb;
207
208 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
209
210 IRDA_ASSERT(self != NULL, return;);
211 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
212
213 /* Deallocate frames waiting to be sent */
214 while ((skb = skb_dequeue(&self->tx_queue)) != NULL)
215 dev_kfree_skb(skb);
216
217 /* Deallocate received frames */
218 while ((skb = skb_dequeue(&self->rx_queue)) != NULL)
219 dev_kfree_skb(skb);
220
221 /* Deallocate received fragments */
222 while ((skb = skb_dequeue(&self->rx_fragments)) != NULL)
223 dev_kfree_skb(skb);
224}
225
226/*
227 * Function irttp_reassemble (self)
228 *
229 * Makes a new (continuous) skb of all the fragments in the fragment
230 * queue
231 *
232 */
233static struct sk_buff *irttp_reassemble_skb(struct tsap_cb *self)
234{
235 struct sk_buff *skb, *frag;
236 int n = 0; /* Fragment index */
237
238 IRDA_ASSERT(self != NULL, return NULL;);
239 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return NULL;);
240
241 IRDA_DEBUG(2, "%s(), self->rx_sdu_size=%d\n", __FUNCTION__,
242 self->rx_sdu_size);
243
244 skb = dev_alloc_skb(TTP_HEADER + self->rx_sdu_size);
245 if (!skb)
246 return NULL;
247
248 /*
249 * Need to reserve space for TTP header in case this skb needs to
250 * be requeued in case delivery failes
251 */
252 skb_reserve(skb, TTP_HEADER);
253 skb_put(skb, self->rx_sdu_size);
254
255 /*
256 * Copy all fragments to a new buffer
257 */
258 while ((frag = skb_dequeue(&self->rx_fragments)) != NULL) {
259 memcpy(skb->data+n, frag->data, frag->len);
260 n += frag->len;
261
262 dev_kfree_skb(frag);
263 }
264
265 IRDA_DEBUG(2,
266 "%s(), frame len=%d, rx_sdu_size=%d, rx_max_sdu_size=%d\n",
267 __FUNCTION__, n, self->rx_sdu_size, self->rx_max_sdu_size);
268 /* Note : irttp_run_rx_queue() calculate self->rx_sdu_size
269 * by summing the size of all fragments, so we should always
270 * have n == self->rx_sdu_size, except in cases where we
271 * droped the last fragment (when self->rx_sdu_size exceed
272 * self->rx_max_sdu_size), where n < self->rx_sdu_size.
273 * Jean II */
274 IRDA_ASSERT(n <= self->rx_sdu_size, n = self->rx_sdu_size;);
275
276 /* Set the new length */
277 skb_trim(skb, n);
278
279 self->rx_sdu_size = 0;
280
281 return skb;
282}
283
284/*
285 * Function irttp_fragment_skb (skb)
286 *
287 * Fragments a frame and queues all the fragments for transmission
288 *
289 */
290static inline void irttp_fragment_skb(struct tsap_cb *self,
291 struct sk_buff *skb)
292{
293 struct sk_buff *frag;
294 __u8 *frame;
295
296 IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
297
298 IRDA_ASSERT(self != NULL, return;);
299 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
300 IRDA_ASSERT(skb != NULL, return;);
301
302 /*
303 * Split frame into a number of segments
304 */
305 while (skb->len > self->max_seg_size) {
306 IRDA_DEBUG(2, "%s(), fragmenting ...\n", __FUNCTION__);
307
308 /* Make new segment */
Samuel Ortiz485fb2c2006-07-21 14:50:41 -0700309 frag = alloc_skb(self->max_seg_size+self->max_header_size,
310 GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311 if (!frag)
312 return;
313
314 skb_reserve(frag, self->max_header_size);
315
316 /* Copy data from the original skb into this fragment. */
317 memcpy(skb_put(frag, self->max_seg_size), skb->data,
318 self->max_seg_size);
319
320 /* Insert TTP header, with the more bit set */
321 frame = skb_push(frag, TTP_HEADER);
322 frame[0] = TTP_MORE;
323
324 /* Hide the copied data from the original skb */
325 skb_pull(skb, self->max_seg_size);
326
327 /* Queue fragment */
328 skb_queue_tail(&self->tx_queue, frag);
329 }
330 /* Queue what is left of the original skb */
331 IRDA_DEBUG(2, "%s(), queuing last segment\n", __FUNCTION__);
332
333 frame = skb_push(skb, TTP_HEADER);
334 frame[0] = 0x00; /* Clear more bit */
335
336 /* Queue fragment */
337 skb_queue_tail(&self->tx_queue, skb);
338}
339
340/*
341 * Function irttp_param_max_sdu_size (self, param)
342 *
343 * Handle the MaxSduSize parameter in the connect frames, this function
344 * will be called both when this parameter needs to be inserted into, and
345 * extracted from the connect frames
346 */
347static int irttp_param_max_sdu_size(void *instance, irda_param_t *param,
348 int get)
349{
350 struct tsap_cb *self;
351
352 self = (struct tsap_cb *) instance;
353
354 IRDA_ASSERT(self != NULL, return -1;);
355 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
356
357 if (get)
358 param->pv.i = self->tx_max_sdu_size;
359 else
360 self->tx_max_sdu_size = param->pv.i;
361
362 IRDA_DEBUG(1, "%s(), MaxSduSize=%d\n", __FUNCTION__, param->pv.i);
363
364 return 0;
365}
366
367/*************************** CLIENT CALLS ***************************/
368/************************** LMP CALLBACKS **************************/
369/* Everything is happily mixed up. Waiting for next clean up - Jean II */
370
371/*
372 * Function irttp_open_tsap (stsap, notify)
373 *
374 * Create TSAP connection endpoint,
375 */
376struct tsap_cb *irttp_open_tsap(__u8 stsap_sel, int credit, notify_t *notify)
377{
378 struct tsap_cb *self;
379 struct lsap_cb *lsap;
380 notify_t ttp_notify;
381
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382 IRDA_ASSERT(irttp->magic == TTP_MAGIC, return NULL;);
383
384 /* The IrLMP spec (IrLMP 1.1 p10) says that we have the right to
385 * use only 0x01-0x6F. Of course, we can use LSAP_ANY as well.
386 * JeanII */
387 if((stsap_sel != LSAP_ANY) &&
388 ((stsap_sel < 0x01) || (stsap_sel >= 0x70))) {
389 IRDA_DEBUG(0, "%s(), invalid tsap!\n", __FUNCTION__);
390 return NULL;
391 }
392
Panagiotis Issaris0da974f2006-07-21 14:51:30 -0700393 self = kzalloc(sizeof(struct tsap_cb), GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394 if (self == NULL) {
395 IRDA_DEBUG(0, "%s(), unable to kmalloc!\n", __FUNCTION__);
396 return NULL;
397 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 spin_lock_init(&self->lock);
399
400 /* Initialise todo timer */
401 init_timer(&self->todo_timer);
402 self->todo_timer.data = (unsigned long) self;
403 self->todo_timer.function = &irttp_todo_expired;
404
405 /* Initialize callbacks for IrLMP to use */
406 irda_notify_init(&ttp_notify);
407 ttp_notify.connect_confirm = irttp_connect_confirm;
408 ttp_notify.connect_indication = irttp_connect_indication;
409 ttp_notify.disconnect_indication = irttp_disconnect_indication;
410 ttp_notify.data_indication = irttp_data_indication;
411 ttp_notify.udata_indication = irttp_udata_indication;
412 ttp_notify.flow_indication = irttp_flow_indication;
413 if(notify->status_indication != NULL)
414 ttp_notify.status_indication = irttp_status_indication;
415 ttp_notify.instance = self;
416 strncpy(ttp_notify.name, notify->name, NOTIFY_MAX_NAME);
417
418 self->magic = TTP_TSAP_MAGIC;
419 self->connected = FALSE;
420
421 skb_queue_head_init(&self->rx_queue);
422 skb_queue_head_init(&self->tx_queue);
423 skb_queue_head_init(&self->rx_fragments);
424 /*
425 * Create LSAP at IrLMP layer
426 */
427 lsap = irlmp_open_lsap(stsap_sel, &ttp_notify, 0);
428 if (lsap == NULL) {
429 IRDA_WARNING("%s: unable to allocate LSAP!!\n", __FUNCTION__);
430 return NULL;
431 }
432
433 /*
434 * If user specified LSAP_ANY as source TSAP selector, then IrLMP
435 * will replace it with whatever source selector which is free, so
436 * the stsap_sel we have might not be valid anymore
437 */
438 self->stsap_sel = lsap->slsap_sel;
439 IRDA_DEBUG(4, "%s(), stsap_sel=%02x\n", __FUNCTION__, self->stsap_sel);
440
441 self->notify = *notify;
442 self->lsap = lsap;
443
444 hashbin_insert(irttp->tsaps, (irda_queue_t *) self, (long) self, NULL);
445
446 if (credit > TTP_RX_MAX_CREDIT)
447 self->initial_credit = TTP_RX_MAX_CREDIT;
448 else
449 self->initial_credit = credit;
450
451 return self;
452}
453EXPORT_SYMBOL(irttp_open_tsap);
454
455/*
456 * Function irttp_close (handle)
457 *
458 * Remove an instance of a TSAP. This function should only deal with the
459 * deallocation of the TSAP, and resetting of the TSAPs values;
460 *
461 */
462static void __irttp_close_tsap(struct tsap_cb *self)
463{
464 /* First make sure we're connected. */
465 IRDA_ASSERT(self != NULL, return;);
466 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
467
468 irttp_flush_queues(self);
469
470 del_timer(&self->todo_timer);
471
472 /* This one won't be cleaned up if we are disconnect_pend + close_pend
473 * and we receive a disconnect_indication */
474 if (self->disconnect_skb)
475 dev_kfree_skb(self->disconnect_skb);
476
477 self->connected = FALSE;
478 self->magic = ~TTP_TSAP_MAGIC;
479
480 kfree(self);
481}
482
483/*
484 * Function irttp_close (self)
485 *
486 * Remove TSAP from list of all TSAPs and then deallocate all resources
487 * associated with this TSAP
488 *
489 * Note : because we *free* the tsap structure, it is the responsibility
490 * of the caller to make sure we are called only once and to deal with
491 * possible race conditions. - Jean II
492 */
493int irttp_close_tsap(struct tsap_cb *self)
494{
495 struct tsap_cb *tsap;
496
497 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
498
499 IRDA_ASSERT(self != NULL, return -1;);
500 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
501
502 /* Make sure tsap has been disconnected */
503 if (self->connected) {
504 /* Check if disconnect is not pending */
505 if (!test_bit(0, &self->disconnect_pend)) {
506 IRDA_WARNING("%s: TSAP still connected!\n",
507 __FUNCTION__);
508 irttp_disconnect_request(self, NULL, P_NORMAL);
509 }
510 self->close_pend = TRUE;
511 irttp_start_todo_timer(self, HZ/10);
512
513 return 0; /* Will be back! */
514 }
515
516 tsap = hashbin_remove(irttp->tsaps, (long) self, NULL);
517
518 IRDA_ASSERT(tsap == self, return -1;);
519
520 /* Close corresponding LSAP */
521 if (self->lsap) {
522 irlmp_close_lsap(self->lsap);
523 self->lsap = NULL;
524 }
525
526 __irttp_close_tsap(self);
527
528 return 0;
529}
530EXPORT_SYMBOL(irttp_close_tsap);
531
532/*
533 * Function irttp_udata_request (self, skb)
534 *
535 * Send unreliable data on this TSAP
536 *
537 */
538int irttp_udata_request(struct tsap_cb *self, struct sk_buff *skb)
539{
540 IRDA_ASSERT(self != NULL, return -1;);
541 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
542 IRDA_ASSERT(skb != NULL, return -1;);
543
544 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
545
546 /* Check that nothing bad happens */
547 if ((skb->len == 0) || (!self->connected)) {
548 IRDA_DEBUG(1, "%s(), No data, or not connected\n",
549 __FUNCTION__);
550 goto err;
551 }
552
553 if (skb->len > self->max_seg_size) {
554 IRDA_DEBUG(1, "%s(), UData is to large for IrLAP!\n",
555 __FUNCTION__);
556 goto err;
557 }
558
559 irlmp_udata_request(self->lsap, skb);
560 self->stats.tx_packets++;
561
562 return 0;
563
564err:
565 dev_kfree_skb(skb);
566 return -1;
567}
568EXPORT_SYMBOL(irttp_udata_request);
569
570
571/*
572 * Function irttp_data_request (handle, skb)
573 *
574 * Queue frame for transmission. If SAR is enabled, fragement the frame
575 * and queue the fragments for transmission
576 */
577int irttp_data_request(struct tsap_cb *self, struct sk_buff *skb)
578{
579 __u8 *frame;
580 int ret;
581
582 IRDA_ASSERT(self != NULL, return -1;);
583 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
584 IRDA_ASSERT(skb != NULL, return -1;);
585
586 IRDA_DEBUG(2, "%s() : queue len = %d\n", __FUNCTION__,
587 skb_queue_len(&self->tx_queue));
588
589 /* Check that nothing bad happens */
590 if ((skb->len == 0) || (!self->connected)) {
591 IRDA_WARNING("%s: No data, or not connected\n", __FUNCTION__);
592 ret = -ENOTCONN;
593 goto err;
594 }
595
596 /*
597 * Check if SAR is disabled, and the frame is larger than what fits
598 * inside an IrLAP frame
599 */
600 if ((self->tx_max_sdu_size == 0) && (skb->len > self->max_seg_size)) {
601 IRDA_ERROR("%s: SAR disabled, and data is to large for IrLAP!\n",
602 __FUNCTION__);
603 ret = -EMSGSIZE;
604 goto err;
605 }
606
607 /*
608 * Check if SAR is enabled, and the frame is larger than the
609 * TxMaxSduSize
610 */
611 if ((self->tx_max_sdu_size != 0) &&
612 (self->tx_max_sdu_size != TTP_SAR_UNBOUND) &&
613 (skb->len > self->tx_max_sdu_size))
614 {
615 IRDA_ERROR("%s: SAR enabled, but data is larger than TxMaxSduSize!\n",
616 __FUNCTION__);
617 ret = -EMSGSIZE;
618 goto err;
619 }
620 /*
621 * Check if transmit queue is full
622 */
623 if (skb_queue_len(&self->tx_queue) >= TTP_TX_MAX_QUEUE) {
624 /*
625 * Give it a chance to empty itself
626 */
627 irttp_run_tx_queue(self);
628
629 /* Drop packet. This error code should trigger the caller
630 * to resend the data in the client code - Jean II */
631 ret = -ENOBUFS;
632 goto err;
633 }
634
635 /* Queue frame, or queue frame segments */
636 if ((self->tx_max_sdu_size == 0) || (skb->len < self->max_seg_size)) {
637 /* Queue frame */
638 IRDA_ASSERT(skb_headroom(skb) >= TTP_HEADER, return -1;);
639 frame = skb_push(skb, TTP_HEADER);
640 frame[0] = 0x00; /* Clear more bit */
641
642 skb_queue_tail(&self->tx_queue, skb);
643 } else {
644 /*
645 * Fragment the frame, this function will also queue the
646 * fragments, we don't care about the fact the transmit
647 * queue may be overfilled by all the segments for a little
648 * while
649 */
650 irttp_fragment_skb(self, skb);
651 }
652
653 /* Check if we can accept more data from client */
654 if ((!self->tx_sdu_busy) &&
655 (skb_queue_len(&self->tx_queue) > TTP_TX_HIGH_THRESHOLD)) {
656 /* Tx queue filling up, so stop client. */
657 if (self->notify.flow_indication) {
658 self->notify.flow_indication(self->notify.instance,
659 self, FLOW_STOP);
660 }
661 /* self->tx_sdu_busy is the state of the client.
662 * Update state after notifying client to avoid
663 * race condition with irttp_flow_indication().
664 * If the queue empty itself after our test but before
665 * we set the flag, we will fix ourselves below in
666 * irttp_run_tx_queue().
667 * Jean II */
668 self->tx_sdu_busy = TRUE;
669 }
670
671 /* Try to make some progress */
672 irttp_run_tx_queue(self);
673
674 return 0;
675
676err:
677 dev_kfree_skb(skb);
678 return ret;
679}
680EXPORT_SYMBOL(irttp_data_request);
681
682/*
683 * Function irttp_run_tx_queue (self)
684 *
685 * Transmit packets queued for transmission (if possible)
686 *
687 */
688static void irttp_run_tx_queue(struct tsap_cb *self)
689{
690 struct sk_buff *skb;
691 unsigned long flags;
692 int n;
693
694 IRDA_DEBUG(2, "%s() : send_credit = %d, queue_len = %d\n",
695 __FUNCTION__,
696 self->send_credit, skb_queue_len(&self->tx_queue));
697
698 /* Get exclusive access to the tx queue, otherwise don't touch it */
699 if (irda_lock(&self->tx_queue_lock) == FALSE)
700 return;
701
702 /* Try to send out frames as long as we have credits
703 * and as long as LAP is not full. If LAP is full, it will
704 * poll us through irttp_flow_indication() - Jean II */
705 while ((self->send_credit > 0) &&
706 (!irlmp_lap_tx_queue_full(self->lsap)) &&
707 (skb = skb_dequeue(&self->tx_queue)))
708 {
709 /*
710 * Since we can transmit and receive frames concurrently,
711 * the code below is a critical region and we must assure that
712 * nobody messes with the credits while we update them.
713 */
714 spin_lock_irqsave(&self->lock, flags);
715
716 n = self->avail_credit;
717 self->avail_credit = 0;
718
719 /* Only room for 127 credits in frame */
720 if (n > 127) {
721 self->avail_credit = n-127;
722 n = 127;
723 }
724 self->remote_credit += n;
725 self->send_credit--;
726
727 spin_unlock_irqrestore(&self->lock, flags);
728
729 /*
730 * More bit must be set by the data_request() or fragment()
731 * functions
732 */
733 skb->data[0] |= (n & 0x7f);
734
735 /* Detach from socket.
736 * The current skb has a reference to the socket that sent
737 * it (skb->sk). When we pass it to IrLMP, the skb will be
738 * stored in in IrLAP (self->wx_list). When we are within
739 * IrLAP, we lose the notion of socket, so we should not
740 * have a reference to a socket. So, we drop it here.
741 *
742 * Why does it matter ?
743 * When the skb is freed (kfree_skb), if it is associated
744 * with a socket, it release buffer space on the socket
745 * (through sock_wfree() and sock_def_write_space()).
746 * If the socket no longer exist, we may crash. Hard.
747 * When we close a socket, we make sure that associated packets
748 * in IrTTP are freed. However, we have no way to cancel
749 * the packet that we have passed to IrLAP. So, if a packet
750 * remains in IrLAP (retry on the link or else) after we
751 * close the socket, we are dead !
752 * Jean II */
753 if (skb->sk != NULL) {
754 /* IrSOCK application, IrOBEX, ... */
755 skb_orphan(skb);
756 }
757 /* IrCOMM over IrTTP, IrLAN, ... */
758
759 /* Pass the skb to IrLMP - done */
760 irlmp_data_request(self->lsap, skb);
761 self->stats.tx_packets++;
762 }
763
764 /* Check if we can accept more frames from client.
765 * We don't want to wait until the todo timer to do that, and we
766 * can't use tasklets (grr...), so we are obliged to give control
767 * to client. That's ok, this test will be true not too often
768 * (max once per LAP window) and we are called from places
769 * where we can spend a bit of time doing stuff. - Jean II */
770 if ((self->tx_sdu_busy) &&
771 (skb_queue_len(&self->tx_queue) < TTP_TX_LOW_THRESHOLD) &&
772 (!self->close_pend))
773 {
774 if (self->notify.flow_indication)
775 self->notify.flow_indication(self->notify.instance,
776 self, FLOW_START);
777
778 /* self->tx_sdu_busy is the state of the client.
779 * We don't really have a race here, but it's always safer
780 * to update our state after the client - Jean II */
781 self->tx_sdu_busy = FALSE;
782 }
783
784 /* Reset lock */
785 self->tx_queue_lock = 0;
786}
787
788/*
789 * Function irttp_give_credit (self)
790 *
791 * Send a dataless flowdata TTP-PDU and give available credit to peer
792 * TSAP
793 */
794static inline void irttp_give_credit(struct tsap_cb *self)
795{
796 struct sk_buff *tx_skb = NULL;
797 unsigned long flags;
798 int n;
799
800 IRDA_ASSERT(self != NULL, return;);
801 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
802
803 IRDA_DEBUG(4, "%s() send=%d,avail=%d,remote=%d\n",
804 __FUNCTION__,
805 self->send_credit, self->avail_credit, self->remote_credit);
806
807 /* Give credit to peer */
Samuel Ortiz1b0fee72006-09-27 20:06:44 -0700808 tx_skb = alloc_skb(TTP_MAX_HEADER, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809 if (!tx_skb)
810 return;
811
812 /* Reserve space for LMP, and LAP header */
Samuel Ortiz1b0fee72006-09-27 20:06:44 -0700813 skb_reserve(tx_skb, LMP_MAX_HEADER);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700814
815 /*
816 * Since we can transmit and receive frames concurrently,
817 * the code below is a critical region and we must assure that
818 * nobody messes with the credits while we update them.
819 */
820 spin_lock_irqsave(&self->lock, flags);
821
822 n = self->avail_credit;
823 self->avail_credit = 0;
824
825 /* Only space for 127 credits in frame */
826 if (n > 127) {
827 self->avail_credit = n - 127;
828 n = 127;
829 }
830 self->remote_credit += n;
831
832 spin_unlock_irqrestore(&self->lock, flags);
833
834 skb_put(tx_skb, 1);
835 tx_skb->data[0] = (__u8) (n & 0x7f);
836
837 irlmp_data_request(self->lsap, tx_skb);
838 self->stats.tx_packets++;
839}
840
841/*
842 * Function irttp_udata_indication (instance, sap, skb)
843 *
844 * Received some unit-data (unreliable)
845 *
846 */
847static int irttp_udata_indication(void *instance, void *sap,
848 struct sk_buff *skb)
849{
850 struct tsap_cb *self;
851 int err;
852
853 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
854
855 self = (struct tsap_cb *) instance;
856
857 IRDA_ASSERT(self != NULL, return -1;);
858 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
859 IRDA_ASSERT(skb != NULL, return -1;);
860
861 self->stats.rx_packets++;
862
863 /* Just pass data to layer above */
864 if (self->notify.udata_indication) {
865 err = self->notify.udata_indication(self->notify.instance,
866 self,skb);
867 /* Same comment as in irttp_do_data_indication() */
868 if (!err)
869 return 0;
870 }
871 /* Either no handler, or handler returns an error */
872 dev_kfree_skb(skb);
873
874 return 0;
875}
876
877/*
878 * Function irttp_data_indication (instance, sap, skb)
879 *
880 * Receive segment from IrLMP.
881 *
882 */
883static int irttp_data_indication(void *instance, void *sap,
884 struct sk_buff *skb)
885{
886 struct tsap_cb *self;
887 unsigned long flags;
888 int n;
889
890 self = (struct tsap_cb *) instance;
891
892 n = skb->data[0] & 0x7f; /* Extract the credits */
893
894 self->stats.rx_packets++;
895
896 /* Deal with inbound credit
897 * Since we can transmit and receive frames concurrently,
898 * the code below is a critical region and we must assure that
899 * nobody messes with the credits while we update them.
900 */
901 spin_lock_irqsave(&self->lock, flags);
902 self->send_credit += n;
903 if (skb->len > 1)
904 self->remote_credit--;
905 spin_unlock_irqrestore(&self->lock, flags);
906
907 /*
908 * Data or dataless packet? Dataless frames contains only the
909 * TTP_HEADER.
910 */
911 if (skb->len > 1) {
912 /*
913 * We don't remove the TTP header, since we must preserve the
914 * more bit, so the defragment routing knows what to do
915 */
916 skb_queue_tail(&self->rx_queue, skb);
917 } else {
918 /* Dataless flowdata TTP-PDU */
919 dev_kfree_skb(skb);
920 }
921
922
923 /* Push data to the higher layer.
924 * We do it synchronously because running the todo timer for each
925 * receive packet would be too much overhead and latency.
926 * By passing control to the higher layer, we run the risk that
927 * it may take time or grab a lock. Most often, the higher layer
928 * will only put packet in a queue.
929 * Anyway, packets are only dripping through the IrDA, so we can
930 * have time before the next packet.
931 * Further, we are run from NET_BH, so the worse that can happen is
932 * us missing the optimal time to send back the PF bit in LAP.
933 * Jean II */
934 irttp_run_rx_queue(self);
935
936 /* We now give credits to peer in irttp_run_rx_queue().
937 * We need to send credit *NOW*, otherwise we are going
938 * to miss the next Tx window. The todo timer may take
939 * a while before it's run... - Jean II */
940
941 /*
942 * If the peer device has given us some credits and we didn't have
943 * anyone from before, then we need to shedule the tx queue.
944 * We need to do that because our Tx have stopped (so we may not
945 * get any LAP flow indication) and the user may be stopped as
946 * well. - Jean II
947 */
948 if (self->send_credit == n) {
949 /* Restart pushing stuff to LAP */
950 irttp_run_tx_queue(self);
951 /* Note : we don't want to schedule the todo timer
952 * because it has horrible latency. No tasklets
953 * because the tasklet API is broken. - Jean II */
954 }
955
956 return 0;
957}
958
959/*
960 * Function irttp_status_indication (self, reason)
961 *
962 * Status_indication, just pass to the higher layer...
963 *
964 */
965static void irttp_status_indication(void *instance,
966 LINK_STATUS link, LOCK_STATUS lock)
967{
968 struct tsap_cb *self;
969
970 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
971
972 self = (struct tsap_cb *) instance;
973
974 IRDA_ASSERT(self != NULL, return;);
975 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
976
977 /* Check if client has already closed the TSAP and gone away */
978 if (self->close_pend)
979 return;
980
981 /*
982 * Inform service user if he has requested it
983 */
984 if (self->notify.status_indication != NULL)
985 self->notify.status_indication(self->notify.instance,
986 link, lock);
987 else
988 IRDA_DEBUG(2, "%s(), no handler\n", __FUNCTION__);
989}
990
991/*
992 * Function irttp_flow_indication (self, reason)
993 *
994 * Flow_indication : IrLAP tells us to send more data.
995 *
996 */
997static void irttp_flow_indication(void *instance, void *sap, LOCAL_FLOW flow)
998{
999 struct tsap_cb *self;
1000
1001 self = (struct tsap_cb *) instance;
1002
1003 IRDA_ASSERT(self != NULL, return;);
1004 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1005
1006 IRDA_DEBUG(4, "%s(instance=%p)\n", __FUNCTION__, self);
1007
1008 /* We are "polled" directly from LAP, and the LAP want to fill
1009 * its Tx window. We want to do our best to send it data, so that
1010 * we maximise the window. On the other hand, we want to limit the
1011 * amount of work here so that LAP doesn't hang forever waiting
1012 * for packets. - Jean II */
1013
1014 /* Try to send some packets. Currently, LAP calls us every time
1015 * there is one free slot, so we will send only one packet.
1016 * This allow the scheduler to do its round robin - Jean II */
1017 irttp_run_tx_queue(self);
1018
1019 /* Note regarding the interraction with higher layer.
1020 * irttp_run_tx_queue() may call the client when its queue
1021 * start to empty, via notify.flow_indication(). Initially.
1022 * I wanted this to happen in a tasklet, to avoid client
1023 * grabbing the CPU, but we can't use tasklets safely. And timer
1024 * is definitely too slow.
1025 * This will happen only once per LAP window, and usually at
1026 * the third packet (unless window is smaller). LAP is still
1027 * doing mtt and sending first packet so it's sort of OK
1028 * to do that. Jean II */
1029
1030 /* If we need to send disconnect. try to do it now */
1031 if(self->disconnect_pend)
1032 irttp_start_todo_timer(self, 0);
1033}
1034
1035/*
1036 * Function irttp_flow_request (self, command)
1037 *
1038 * This function could be used by the upper layers to tell IrTTP to stop
1039 * delivering frames if the receive queues are starting to get full, or
1040 * to tell IrTTP to start delivering frames again.
1041 */
1042void irttp_flow_request(struct tsap_cb *self, LOCAL_FLOW flow)
1043{
1044 IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
1045
1046 IRDA_ASSERT(self != NULL, return;);
1047 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1048
1049 switch (flow) {
1050 case FLOW_STOP:
1051 IRDA_DEBUG(1, "%s(), flow stop\n", __FUNCTION__);
1052 self->rx_sdu_busy = TRUE;
1053 break;
1054 case FLOW_START:
1055 IRDA_DEBUG(1, "%s(), flow start\n", __FUNCTION__);
1056 self->rx_sdu_busy = FALSE;
1057
1058 /* Client say he can accept more data, try to free our
1059 * queues ASAP - Jean II */
1060 irttp_run_rx_queue(self);
1061
1062 break;
1063 default:
1064 IRDA_DEBUG(1, "%s(), Unknown flow command!\n", __FUNCTION__);
1065 }
1066}
1067EXPORT_SYMBOL(irttp_flow_request);
1068
1069/*
1070 * Function irttp_connect_request (self, dtsap_sel, daddr, qos)
1071 *
1072 * Try to connect to remote destination TSAP selector
1073 *
1074 */
1075int irttp_connect_request(struct tsap_cb *self, __u8 dtsap_sel,
1076 __u32 saddr, __u32 daddr,
1077 struct qos_info *qos, __u32 max_sdu_size,
1078 struct sk_buff *userdata)
1079{
1080 struct sk_buff *tx_skb;
1081 __u8 *frame;
1082 __u8 n;
1083
1084 IRDA_DEBUG(4, "%s(), max_sdu_size=%d\n", __FUNCTION__, max_sdu_size);
1085
1086 IRDA_ASSERT(self != NULL, return -EBADR;);
1087 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -EBADR;);
1088
1089 if (self->connected) {
1090 if(userdata)
1091 dev_kfree_skb(userdata);
1092 return -EISCONN;
1093 }
1094
1095 /* Any userdata supplied? */
1096 if (userdata == NULL) {
Samuel Ortiz1b0fee72006-09-27 20:06:44 -07001097 tx_skb = alloc_skb(TTP_MAX_HEADER + TTP_SAR_HEADER,
1098 GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099 if (!tx_skb)
1100 return -ENOMEM;
1101
1102 /* Reserve space for MUX_CONTROL and LAP header */
1103 skb_reserve(tx_skb, TTP_MAX_HEADER);
1104 } else {
1105 tx_skb = userdata;
1106 /*
1107 * Check that the client has reserved enough space for
1108 * headers
1109 */
1110 IRDA_ASSERT(skb_headroom(userdata) >= TTP_MAX_HEADER,
1111 { dev_kfree_skb(userdata); return -1; } );
1112 }
1113
1114 /* Initialize connection parameters */
1115 self->connected = FALSE;
1116 self->avail_credit = 0;
1117 self->rx_max_sdu_size = max_sdu_size;
1118 self->rx_sdu_size = 0;
1119 self->rx_sdu_busy = FALSE;
1120 self->dtsap_sel = dtsap_sel;
1121
1122 n = self->initial_credit;
1123
1124 self->remote_credit = 0;
1125 self->send_credit = 0;
1126
1127 /*
1128 * Give away max 127 credits for now
1129 */
1130 if (n > 127) {
1131 self->avail_credit=n-127;
1132 n = 127;
1133 }
1134
1135 self->remote_credit = n;
1136
1137 /* SAR enabled? */
1138 if (max_sdu_size > 0) {
1139 IRDA_ASSERT(skb_headroom(tx_skb) >= (TTP_MAX_HEADER + TTP_SAR_HEADER),
1140 { dev_kfree_skb(tx_skb); return -1; } );
1141
1142 /* Insert SAR parameters */
1143 frame = skb_push(tx_skb, TTP_HEADER+TTP_SAR_HEADER);
1144
1145 frame[0] = TTP_PARAMETERS | n;
1146 frame[1] = 0x04; /* Length */
1147 frame[2] = 0x01; /* MaxSduSize */
1148 frame[3] = 0x02; /* Value length */
1149
1150 put_unaligned(cpu_to_be16((__u16) max_sdu_size),
Al Viro448c31a2006-11-14 20:47:46 -08001151 (__be16 *)(frame+4));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001152 } else {
1153 /* Insert plain TTP header */
1154 frame = skb_push(tx_skb, TTP_HEADER);
1155
1156 /* Insert initial credit in frame */
1157 frame[0] = n & 0x7f;
1158 }
1159
1160 /* Connect with IrLMP. No QoS parameters for now */
1161 return irlmp_connect_request(self->lsap, dtsap_sel, saddr, daddr, qos,
1162 tx_skb);
1163}
1164EXPORT_SYMBOL(irttp_connect_request);
1165
1166/*
1167 * Function irttp_connect_confirm (handle, qos, skb)
1168 *
1169 * Sevice user confirms TSAP connection with peer.
1170 *
1171 */
1172static void irttp_connect_confirm(void *instance, void *sap,
1173 struct qos_info *qos, __u32 max_seg_size,
1174 __u8 max_header_size, struct sk_buff *skb)
1175{
1176 struct tsap_cb *self;
1177 int parameters;
1178 int ret;
1179 __u8 plen;
1180 __u8 n;
1181
1182 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
1183
1184 self = (struct tsap_cb *) instance;
1185
1186 IRDA_ASSERT(self != NULL, return;);
1187 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1188 IRDA_ASSERT(skb != NULL, return;);
1189
1190 self->max_seg_size = max_seg_size - TTP_HEADER;
1191 self->max_header_size = max_header_size + TTP_HEADER;
1192
1193 /*
1194 * Check if we have got some QoS parameters back! This should be the
1195 * negotiated QoS for the link.
1196 */
1197 if (qos) {
1198 IRDA_DEBUG(4, "IrTTP, Negotiated BAUD_RATE: %02x\n",
1199 qos->baud_rate.bits);
1200 IRDA_DEBUG(4, "IrTTP, Negotiated BAUD_RATE: %d bps.\n",
1201 qos->baud_rate.value);
1202 }
1203
1204 n = skb->data[0] & 0x7f;
1205
1206 IRDA_DEBUG(4, "%s(), Initial send_credit=%d\n", __FUNCTION__, n);
1207
1208 self->send_credit = n;
1209 self->tx_max_sdu_size = 0;
1210 self->connected = TRUE;
1211
1212 parameters = skb->data[0] & 0x80;
1213
1214 IRDA_ASSERT(skb->len >= TTP_HEADER, return;);
1215 skb_pull(skb, TTP_HEADER);
1216
1217 if (parameters) {
1218 plen = skb->data[0];
1219
1220 ret = irda_param_extract_all(self, skb->data+1,
1221 IRDA_MIN(skb->len-1, plen),
1222 &param_info);
1223
1224 /* Any errors in the parameter list? */
1225 if (ret < 0) {
1226 IRDA_WARNING("%s: error extracting parameters\n",
1227 __FUNCTION__);
1228 dev_kfree_skb(skb);
1229
1230 /* Do not accept this connection attempt */
1231 return;
1232 }
1233 /* Remove parameters */
1234 skb_pull(skb, IRDA_MIN(skb->len, plen+1));
1235 }
1236
1237 IRDA_DEBUG(4, "%s() send=%d,avail=%d,remote=%d\n", __FUNCTION__,
1238 self->send_credit, self->avail_credit, self->remote_credit);
1239
1240 IRDA_DEBUG(2, "%s(), MaxSduSize=%d\n", __FUNCTION__,
1241 self->tx_max_sdu_size);
1242
1243 if (self->notify.connect_confirm) {
1244 self->notify.connect_confirm(self->notify.instance, self, qos,
1245 self->tx_max_sdu_size,
1246 self->max_header_size, skb);
1247 } else
1248 dev_kfree_skb(skb);
1249}
1250
1251/*
1252 * Function irttp_connect_indication (handle, skb)
1253 *
1254 * Some other device is connecting to this TSAP
1255 *
1256 */
1257void irttp_connect_indication(void *instance, void *sap, struct qos_info *qos,
1258 __u32 max_seg_size, __u8 max_header_size,
1259 struct sk_buff *skb)
1260{
1261 struct tsap_cb *self;
1262 struct lsap_cb *lsap;
1263 int parameters;
1264 int ret;
1265 __u8 plen;
1266 __u8 n;
1267
1268 self = (struct tsap_cb *) instance;
1269
1270 IRDA_ASSERT(self != NULL, return;);
1271 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1272 IRDA_ASSERT(skb != NULL, return;);
1273
1274 lsap = (struct lsap_cb *) sap;
1275
1276 self->max_seg_size = max_seg_size - TTP_HEADER;
1277 self->max_header_size = max_header_size+TTP_HEADER;
1278
1279 IRDA_DEBUG(4, "%s(), TSAP sel=%02x\n", __FUNCTION__, self->stsap_sel);
1280
1281 /* Need to update dtsap_sel if its equal to LSAP_ANY */
1282 self->dtsap_sel = lsap->dlsap_sel;
1283
1284 n = skb->data[0] & 0x7f;
1285
1286 self->send_credit = n;
1287 self->tx_max_sdu_size = 0;
1288
1289 parameters = skb->data[0] & 0x80;
1290
1291 IRDA_ASSERT(skb->len >= TTP_HEADER, return;);
1292 skb_pull(skb, TTP_HEADER);
1293
1294 if (parameters) {
1295 plen = skb->data[0];
1296
1297 ret = irda_param_extract_all(self, skb->data+1,
1298 IRDA_MIN(skb->len-1, plen),
1299 &param_info);
1300
1301 /* Any errors in the parameter list? */
1302 if (ret < 0) {
1303 IRDA_WARNING("%s: error extracting parameters\n",
1304 __FUNCTION__);
1305 dev_kfree_skb(skb);
1306
1307 /* Do not accept this connection attempt */
1308 return;
1309 }
1310
1311 /* Remove parameters */
1312 skb_pull(skb, IRDA_MIN(skb->len, plen+1));
1313 }
1314
1315 if (self->notify.connect_indication) {
1316 self->notify.connect_indication(self->notify.instance, self,
1317 qos, self->tx_max_sdu_size,
1318 self->max_header_size, skb);
1319 } else
1320 dev_kfree_skb(skb);
1321}
1322
1323/*
1324 * Function irttp_connect_response (handle, userdata)
1325 *
1326 * Service user is accepting the connection, just pass it down to
1327 * IrLMP!
1328 *
1329 */
1330int irttp_connect_response(struct tsap_cb *self, __u32 max_sdu_size,
1331 struct sk_buff *userdata)
1332{
1333 struct sk_buff *tx_skb;
1334 __u8 *frame;
1335 int ret;
1336 __u8 n;
1337
1338 IRDA_ASSERT(self != NULL, return -1;);
1339 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
1340
1341 IRDA_DEBUG(4, "%s(), Source TSAP selector=%02x\n", __FUNCTION__,
1342 self->stsap_sel);
1343
1344 /* Any userdata supplied? */
1345 if (userdata == NULL) {
Samuel Ortiz1b0fee72006-09-27 20:06:44 -07001346 tx_skb = alloc_skb(TTP_MAX_HEADER + TTP_SAR_HEADER,
1347 GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001348 if (!tx_skb)
1349 return -ENOMEM;
1350
1351 /* Reserve space for MUX_CONTROL and LAP header */
1352 skb_reserve(tx_skb, TTP_MAX_HEADER);
1353 } else {
1354 tx_skb = userdata;
1355 /*
1356 * Check that the client has reserved enough space for
1357 * headers
1358 */
1359 IRDA_ASSERT(skb_headroom(userdata) >= TTP_MAX_HEADER,
1360 { dev_kfree_skb(userdata); return -1; } );
1361 }
1362
1363 self->avail_credit = 0;
1364 self->remote_credit = 0;
1365 self->rx_max_sdu_size = max_sdu_size;
1366 self->rx_sdu_size = 0;
1367 self->rx_sdu_busy = FALSE;
1368
1369 n = self->initial_credit;
1370
1371 /* Frame has only space for max 127 credits (7 bits) */
1372 if (n > 127) {
1373 self->avail_credit = n - 127;
1374 n = 127;
1375 }
1376
1377 self->remote_credit = n;
1378 self->connected = TRUE;
1379
1380 /* SAR enabled? */
1381 if (max_sdu_size > 0) {
1382 IRDA_ASSERT(skb_headroom(tx_skb) >= (TTP_MAX_HEADER + TTP_SAR_HEADER),
1383 { dev_kfree_skb(tx_skb); return -1; } );
1384
1385 /* Insert TTP header with SAR parameters */
1386 frame = skb_push(tx_skb, TTP_HEADER+TTP_SAR_HEADER);
1387
1388 frame[0] = TTP_PARAMETERS | n;
1389 frame[1] = 0x04; /* Length */
1390
1391 /* irda_param_insert(self, IRTTP_MAX_SDU_SIZE, frame+1, */
1392/* TTP_SAR_HEADER, &param_info) */
1393
1394 frame[2] = 0x01; /* MaxSduSize */
1395 frame[3] = 0x02; /* Value length */
1396
1397 put_unaligned(cpu_to_be16((__u16) max_sdu_size),
Al Viro448c31a2006-11-14 20:47:46 -08001398 (__be16 *)(frame+4));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001399 } else {
1400 /* Insert TTP header */
1401 frame = skb_push(tx_skb, TTP_HEADER);
1402
1403 frame[0] = n & 0x7f;
1404 }
1405
1406 ret = irlmp_connect_response(self->lsap, tx_skb);
1407
1408 return ret;
1409}
1410EXPORT_SYMBOL(irttp_connect_response);
1411
1412/*
1413 * Function irttp_dup (self, instance)
1414 *
1415 * Duplicate TSAP, can be used by servers to confirm a connection on a
1416 * new TSAP so it can keep listening on the old one.
1417 */
1418struct tsap_cb *irttp_dup(struct tsap_cb *orig, void *instance)
1419{
1420 struct tsap_cb *new;
1421 unsigned long flags;
1422
1423 IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
1424
1425 /* Protect our access to the old tsap instance */
1426 spin_lock_irqsave(&irttp->tsaps->hb_spinlock, flags);
1427
1428 /* Find the old instance */
1429 if (!hashbin_find(irttp->tsaps, (long) orig, NULL)) {
1430 IRDA_DEBUG(0, "%s(), unable to find TSAP\n", __FUNCTION__);
1431 spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
1432 return NULL;
1433 }
1434
1435 /* Allocate a new instance */
1436 new = kmalloc(sizeof(struct tsap_cb), GFP_ATOMIC);
1437 if (!new) {
1438 IRDA_DEBUG(0, "%s(), unable to kmalloc\n", __FUNCTION__);
1439 spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
1440 return NULL;
1441 }
1442 /* Dup */
1443 memcpy(new, orig, sizeof(struct tsap_cb));
1444
1445 /* We don't need the old instance any more */
1446 spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
1447
1448 /* Try to dup the LSAP (may fail if we were too slow) */
1449 new->lsap = irlmp_dup(orig->lsap, new);
1450 if (!new->lsap) {
1451 IRDA_DEBUG(0, "%s(), dup failed!\n", __FUNCTION__);
1452 kfree(new);
1453 return NULL;
1454 }
1455
1456 /* Not everything should be copied */
1457 new->notify.instance = instance;
1458 init_timer(&new->todo_timer);
1459
1460 skb_queue_head_init(&new->rx_queue);
1461 skb_queue_head_init(&new->tx_queue);
1462 skb_queue_head_init(&new->rx_fragments);
1463
1464 /* This is locked */
1465 hashbin_insert(irttp->tsaps, (irda_queue_t *) new, (long) new, NULL);
1466
1467 return new;
1468}
1469EXPORT_SYMBOL(irttp_dup);
1470
1471/*
1472 * Function irttp_disconnect_request (self)
1473 *
1474 * Close this connection please! If priority is high, the queued data
1475 * segments, if any, will be deallocated first
1476 *
1477 */
1478int irttp_disconnect_request(struct tsap_cb *self, struct sk_buff *userdata,
1479 int priority)
1480{
1481 int ret;
1482
1483 IRDA_ASSERT(self != NULL, return -1;);
1484 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
1485
1486 /* Already disconnected? */
1487 if (!self->connected) {
1488 IRDA_DEBUG(4, "%s(), already disconnected!\n", __FUNCTION__);
1489 if (userdata)
1490 dev_kfree_skb(userdata);
1491 return -1;
1492 }
1493
1494 /* Disconnect already pending ?
1495 * We need to use an atomic operation to prevent reentry. This
1496 * function may be called from various context, like user, timer
1497 * for following a disconnect_indication() (i.e. net_bh).
1498 * Jean II */
1499 if(test_and_set_bit(0, &self->disconnect_pend)) {
1500 IRDA_DEBUG(0, "%s(), disconnect already pending\n",
1501 __FUNCTION__);
1502 if (userdata)
1503 dev_kfree_skb(userdata);
1504
1505 /* Try to make some progress */
1506 irttp_run_tx_queue(self);
1507 return -1;
1508 }
1509
1510 /*
1511 * Check if there is still data segments in the transmit queue
1512 */
David S. Millerb03efcf2005-07-08 14:57:23 -07001513 if (!skb_queue_empty(&self->tx_queue)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001514 if (priority == P_HIGH) {
1515 /*
1516 * No need to send the queued data, if we are
1517 * disconnecting right now since the data will
1518 * not have any usable connection to be sent on
1519 */
1520 IRDA_DEBUG(1, "%s(): High priority!!()\n", __FUNCTION__);
1521 irttp_flush_queues(self);
1522 } else if (priority == P_NORMAL) {
1523 /*
1524 * Must delay disconnect until after all data segments
1525 * have been sent and the tx_queue is empty
1526 */
1527 /* We'll reuse this one later for the disconnect */
1528 self->disconnect_skb = userdata; /* May be NULL */
1529
1530 irttp_run_tx_queue(self);
1531
1532 irttp_start_todo_timer(self, HZ/10);
1533 return -1;
1534 }
1535 }
1536 /* Note : we don't need to check if self->rx_queue is full and the
1537 * state of self->rx_sdu_busy because the disconnect response will
1538 * be sent at the LMP level (so even if the peer has its Tx queue
1539 * full of data). - Jean II */
1540
1541 IRDA_DEBUG(1, "%s(), Disconnecting ...\n", __FUNCTION__);
1542 self->connected = FALSE;
1543
1544 if (!userdata) {
1545 struct sk_buff *tx_skb;
Samuel Ortiz1b0fee72006-09-27 20:06:44 -07001546 tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001547 if (!tx_skb)
1548 return -ENOMEM;
1549
1550 /*
1551 * Reserve space for MUX and LAP header
1552 */
Samuel Ortiz1b0fee72006-09-27 20:06:44 -07001553 skb_reserve(tx_skb, LMP_MAX_HEADER);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001554
1555 userdata = tx_skb;
1556 }
1557 ret = irlmp_disconnect_request(self->lsap, userdata);
1558
1559 /* The disconnect is no longer pending */
1560 clear_bit(0, &self->disconnect_pend); /* FALSE */
1561
1562 return ret;
1563}
1564EXPORT_SYMBOL(irttp_disconnect_request);
1565
1566/*
1567 * Function irttp_disconnect_indication (self, reason)
1568 *
1569 * Disconnect indication, TSAP disconnected by peer?
1570 *
1571 */
1572void irttp_disconnect_indication(void *instance, void *sap, LM_REASON reason,
1573 struct sk_buff *skb)
1574{
1575 struct tsap_cb *self;
1576
1577 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
1578
1579 self = (struct tsap_cb *) instance;
1580
1581 IRDA_ASSERT(self != NULL, return;);
1582 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1583
1584 /* Prevent higher layer to send more data */
1585 self->connected = FALSE;
1586
1587 /* Check if client has already tried to close the TSAP */
1588 if (self->close_pend) {
1589 /* In this case, the higher layer is probably gone. Don't
1590 * bother it and clean up the remains - Jean II */
1591 if (skb)
1592 dev_kfree_skb(skb);
1593 irttp_close_tsap(self);
1594 return;
1595 }
1596
1597 /* If we are here, we assume that is the higher layer is still
1598 * waiting for the disconnect notification and able to process it,
1599 * even if he tried to disconnect. Otherwise, it would have already
1600 * attempted to close the tsap and self->close_pend would be TRUE.
1601 * Jean II */
1602
1603 /* No need to notify the client if has already tried to disconnect */
1604 if(self->notify.disconnect_indication)
1605 self->notify.disconnect_indication(self->notify.instance, self,
1606 reason, skb);
1607 else
1608 if (skb)
1609 dev_kfree_skb(skb);
1610}
1611
1612/*
1613 * Function irttp_do_data_indication (self, skb)
1614 *
1615 * Try to deliver reassembled skb to layer above, and requeue it if that
1616 * for some reason should fail. We mark rx sdu as busy to apply back
1617 * pressure is necessary.
1618 */
1619static void irttp_do_data_indication(struct tsap_cb *self, struct sk_buff *skb)
1620{
1621 int err;
1622
1623 /* Check if client has already closed the TSAP and gone away */
1624 if (self->close_pend) {
1625 dev_kfree_skb(skb);
1626 return;
1627 }
1628
1629 err = self->notify.data_indication(self->notify.instance, self, skb);
1630
1631 /* Usually the layer above will notify that it's input queue is
1632 * starting to get filled by using the flow request, but this may
1633 * be difficult, so it can instead just refuse to eat it and just
1634 * give an error back
1635 */
1636 if (err) {
1637 IRDA_DEBUG(0, "%s() requeueing skb!\n", __FUNCTION__);
1638
1639 /* Make sure we take a break */
1640 self->rx_sdu_busy = TRUE;
1641
1642 /* Need to push the header in again */
1643 skb_push(skb, TTP_HEADER);
1644 skb->data[0] = 0x00; /* Make sure MORE bit is cleared */
1645
1646 /* Put skb back on queue */
1647 skb_queue_head(&self->rx_queue, skb);
1648 }
1649}
1650
1651/*
1652 * Function irttp_run_rx_queue (self)
1653 *
1654 * Check if we have any frames to be transmitted, or if we have any
1655 * available credit to give away.
1656 */
1657void irttp_run_rx_queue(struct tsap_cb *self)
1658{
1659 struct sk_buff *skb;
1660 int more = 0;
1661
1662 IRDA_DEBUG(2, "%s() send=%d,avail=%d,remote=%d\n", __FUNCTION__,
1663 self->send_credit, self->avail_credit, self->remote_credit);
1664
1665 /* Get exclusive access to the rx queue, otherwise don't touch it */
1666 if (irda_lock(&self->rx_queue_lock) == FALSE)
1667 return;
1668
1669 /*
1670 * Reassemble all frames in receive queue and deliver them
1671 */
1672 while (!self->rx_sdu_busy && (skb = skb_dequeue(&self->rx_queue))) {
1673 /* This bit will tell us if it's the last fragment or not */
1674 more = skb->data[0] & 0x80;
1675
1676 /* Remove TTP header */
1677 skb_pull(skb, TTP_HEADER);
1678
1679 /* Add the length of the remaining data */
1680 self->rx_sdu_size += skb->len;
1681
1682 /*
1683 * If SAR is disabled, or user has requested no reassembly
1684 * of received fragments then we just deliver them
1685 * immediately. This can be requested by clients that
1686 * implements byte streams without any message boundaries
1687 */
1688 if (self->rx_max_sdu_size == TTP_SAR_DISABLE) {
1689 irttp_do_data_indication(self, skb);
1690 self->rx_sdu_size = 0;
1691
1692 continue;
1693 }
1694
1695 /* Check if this is a fragment, and not the last fragment */
1696 if (more) {
1697 /*
1698 * Queue the fragment if we still are within the
1699 * limits of the maximum size of the rx_sdu
1700 */
1701 if (self->rx_sdu_size <= self->rx_max_sdu_size) {
1702 IRDA_DEBUG(4, "%s(), queueing frag\n",
1703 __FUNCTION__);
1704 skb_queue_tail(&self->rx_fragments, skb);
1705 } else {
1706 /* Free the part of the SDU that is too big */
1707 dev_kfree_skb(skb);
1708 }
1709 continue;
1710 }
1711 /*
1712 * This is the last fragment, so time to reassemble!
1713 */
1714 if ((self->rx_sdu_size <= self->rx_max_sdu_size) ||
1715 (self->rx_max_sdu_size == TTP_SAR_UNBOUND))
1716 {
1717 /*
1718 * A little optimizing. Only queue the fragment if
1719 * there are other fragments. Since if this is the
1720 * last and only fragment, there is no need to
1721 * reassemble :-)
1722 */
1723 if (!skb_queue_empty(&self->rx_fragments)) {
1724 skb_queue_tail(&self->rx_fragments,
1725 skb);
1726
1727 skb = irttp_reassemble_skb(self);
1728 }
1729
1730 /* Now we can deliver the reassembled skb */
1731 irttp_do_data_indication(self, skb);
1732 } else {
1733 IRDA_DEBUG(1, "%s(), Truncated frame\n", __FUNCTION__);
1734
1735 /* Free the part of the SDU that is too big */
1736 dev_kfree_skb(skb);
1737
1738 /* Deliver only the valid but truncated part of SDU */
1739 skb = irttp_reassemble_skb(self);
1740
1741 irttp_do_data_indication(self, skb);
1742 }
1743 self->rx_sdu_size = 0;
1744 }
1745
1746 /*
1747 * It's not trivial to keep track of how many credits are available
1748 * by incrementing at each packet, because delivery may fail
1749 * (irttp_do_data_indication() may requeue the frame) and because
1750 * we need to take care of fragmentation.
1751 * We want the other side to send up to initial_credit packets.
1752 * We have some frames in our queues, and we have already allowed it
1753 * to send remote_credit.
1754 * No need to spinlock, write is atomic and self correcting...
1755 * Jean II
1756 */
1757 self->avail_credit = (self->initial_credit -
1758 (self->remote_credit +
1759 skb_queue_len(&self->rx_queue) +
1760 skb_queue_len(&self->rx_fragments)));
1761
1762 /* Do we have too much credits to send to peer ? */
1763 if ((self->remote_credit <= TTP_RX_MIN_CREDIT) &&
1764 (self->avail_credit > 0)) {
1765 /* Send explicit credit frame */
1766 irttp_give_credit(self);
1767 /* Note : do *NOT* check if tx_queue is non-empty, that
1768 * will produce deadlocks. I repeat : send a credit frame
1769 * even if we have something to send in our Tx queue.
1770 * If we have credits, it means that our Tx queue is blocked.
1771 *
1772 * Let's suppose the peer can't keep up with our Tx. He will
1773 * flow control us by not sending us any credits, and we
1774 * will stop Tx and start accumulating credits here.
1775 * Up to the point where the peer will stop its Tx queue,
1776 * for lack of credits.
1777 * Let's assume the peer application is single threaded.
1778 * It will block on Tx and never consume any Rx buffer.
1779 * Deadlock. Guaranteed. - Jean II
1780 */
1781 }
1782
1783 /* Reset lock */
1784 self->rx_queue_lock = 0;
1785}
1786
1787#ifdef CONFIG_PROC_FS
1788struct irttp_iter_state {
1789 int id;
1790};
1791
1792static void *irttp_seq_start(struct seq_file *seq, loff_t *pos)
1793{
1794 struct irttp_iter_state *iter = seq->private;
1795 struct tsap_cb *self;
1796
1797 /* Protect our access to the tsap list */
1798 spin_lock_irq(&irttp->tsaps->hb_spinlock);
1799 iter->id = 0;
1800
1801 for (self = (struct tsap_cb *) hashbin_get_first(irttp->tsaps);
1802 self != NULL;
1803 self = (struct tsap_cb *) hashbin_get_next(irttp->tsaps)) {
1804 if (iter->id == *pos)
1805 break;
1806 ++iter->id;
1807 }
1808
1809 return self;
1810}
1811
1812static void *irttp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1813{
1814 struct irttp_iter_state *iter = seq->private;
1815
1816 ++*pos;
1817 ++iter->id;
1818 return (void *) hashbin_get_next(irttp->tsaps);
1819}
1820
1821static void irttp_seq_stop(struct seq_file *seq, void *v)
1822{
1823 spin_unlock_irq(&irttp->tsaps->hb_spinlock);
1824}
1825
1826static int irttp_seq_show(struct seq_file *seq, void *v)
1827{
1828 const struct irttp_iter_state *iter = seq->private;
1829 const struct tsap_cb *self = v;
1830
1831 seq_printf(seq, "TSAP %d, ", iter->id);
1832 seq_printf(seq, "stsap_sel: %02x, ",
1833 self->stsap_sel);
1834 seq_printf(seq, "dtsap_sel: %02x\n",
1835 self->dtsap_sel);
1836 seq_printf(seq, " connected: %s, ",
1837 self->connected? "TRUE":"FALSE");
1838 seq_printf(seq, "avail credit: %d, ",
1839 self->avail_credit);
1840 seq_printf(seq, "remote credit: %d, ",
1841 self->remote_credit);
1842 seq_printf(seq, "send credit: %d\n",
1843 self->send_credit);
1844 seq_printf(seq, " tx packets: %ld, ",
1845 self->stats.tx_packets);
1846 seq_printf(seq, "rx packets: %ld, ",
1847 self->stats.rx_packets);
1848 seq_printf(seq, "tx_queue len: %d ",
1849 skb_queue_len(&self->tx_queue));
1850 seq_printf(seq, "rx_queue len: %d\n",
1851 skb_queue_len(&self->rx_queue));
1852 seq_printf(seq, " tx_sdu_busy: %s, ",
1853 self->tx_sdu_busy? "TRUE":"FALSE");
1854 seq_printf(seq, "rx_sdu_busy: %s\n",
1855 self->rx_sdu_busy? "TRUE":"FALSE");
1856 seq_printf(seq, " max_seg_size: %d, ",
1857 self->max_seg_size);
1858 seq_printf(seq, "tx_max_sdu_size: %d, ",
1859 self->tx_max_sdu_size);
1860 seq_printf(seq, "rx_max_sdu_size: %d\n",
1861 self->rx_max_sdu_size);
1862
1863 seq_printf(seq, " Used by (%s)\n\n",
1864 self->notify.name);
1865 return 0;
1866}
1867
1868static struct seq_operations irttp_seq_ops = {
1869 .start = irttp_seq_start,
1870 .next = irttp_seq_next,
1871 .stop = irttp_seq_stop,
1872 .show = irttp_seq_show,
1873};
1874
1875static int irttp_seq_open(struct inode *inode, struct file *file)
1876{
1877 struct seq_file *seq;
1878 int rc = -ENOMEM;
1879 struct irttp_iter_state *s;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001880
Panagiotis Issaris0da974f2006-07-21 14:51:30 -07001881 s = kzalloc(sizeof(*s), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001882 if (!s)
1883 goto out;
1884
1885 rc = seq_open(file, &irttp_seq_ops);
1886 if (rc)
1887 goto out_kfree;
1888
1889 seq = file->private_data;
1890 seq->private = s;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001891out:
1892 return rc;
1893out_kfree:
1894 kfree(s);
1895 goto out;
1896}
1897
1898struct file_operations irttp_seq_fops = {
1899 .owner = THIS_MODULE,
1900 .open = irttp_seq_open,
1901 .read = seq_read,
1902 .llseek = seq_lseek,
1903 .release = seq_release_private,
1904};
1905
1906#endif /* PROC_FS */