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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>
29#include <linux/seq_file.h>
30
31#include <asm/byteorder.h>
32#include <asm/unaligned.h>
33
34#include <net/irda/irda.h>
35#include <net/irda/irlap.h>
36#include <net/irda/irlmp.h>
37#include <net/irda/parameters.h>
38#include <net/irda/irttp.h>
39
Alexey Dobriyan8689c072005-09-24 16:55:17 -070040static struct irttp_cb *irttp;
Linus Torvalds1da177e2005-04-16 15:20:36 -070041
42static void __irttp_close_tsap(struct tsap_cb *self);
43
44static int irttp_data_indication(void *instance, void *sap,
45 struct sk_buff *skb);
46static int irttp_udata_indication(void *instance, void *sap,
47 struct sk_buff *skb);
48static void irttp_disconnect_indication(void *instance, void *sap,
49 LM_REASON reason, struct sk_buff *);
50static void irttp_connect_indication(void *instance, void *sap,
51 struct qos_info *qos, __u32 max_sdu_size,
52 __u8 header_size, struct sk_buff *skb);
53static void irttp_connect_confirm(void *instance, void *sap,
54 struct qos_info *qos, __u32 max_sdu_size,
55 __u8 header_size, struct sk_buff *skb);
56static void irttp_run_tx_queue(struct tsap_cb *self);
57static void irttp_run_rx_queue(struct tsap_cb *self);
58
59static void irttp_flush_queues(struct tsap_cb *self);
60static void irttp_fragment_skb(struct tsap_cb *self, struct sk_buff *skb);
61static struct sk_buff *irttp_reassemble_skb(struct tsap_cb *self);
62static void irttp_todo_expired(unsigned long data);
63static int irttp_param_max_sdu_size(void *instance, irda_param_t *param,
64 int get);
65
66static void irttp_flow_indication(void *instance, void *sap, LOCAL_FLOW flow);
67static void irttp_status_indication(void *instance,
68 LINK_STATUS link, LOCK_STATUS lock);
69
70/* Information for parsing parameters in IrTTP */
71static pi_minor_info_t pi_minor_call_table[] = {
72 { NULL, 0 }, /* 0x00 */
73 { irttp_param_max_sdu_size, PV_INTEGER | PV_BIG_ENDIAN } /* 0x01 */
74};
75static pi_major_info_t pi_major_call_table[] = {{ pi_minor_call_table, 2 }};
76static pi_param_info_t param_info = { pi_major_call_table, 1, 0x0f, 4 };
77
78/************************ GLOBAL PROCEDURES ************************/
79
80/*
81 * Function irttp_init (void)
82 *
83 * Initialize the IrTTP layer. Called by module initialization code
84 *
85 */
86int __init irttp_init(void)
87{
Panagiotis Issaris0da974f2006-07-21 14:51:30 -070088 irttp = kzalloc(sizeof(struct irttp_cb), GFP_KERNEL);
Alexey Dobriyan8689c072005-09-24 16:55:17 -070089 if (irttp == NULL)
90 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -070091
92 irttp->magic = TTP_MAGIC;
93
94 irttp->tsaps = hashbin_new(HB_LOCK);
95 if (!irttp->tsaps) {
96 IRDA_ERROR("%s: can't allocate IrTTP hashbin!\n",
97 __FUNCTION__);
Alexey Dobriyan15166fadb2005-09-24 16:54:50 -070098 kfree(irttp);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099 return -ENOMEM;
100 }
101
102 return 0;
103}
104
105/*
106 * Function irttp_cleanup (void)
107 *
108 * Called by module destruction/cleanup code
109 *
110 */
111void __exit irttp_cleanup(void)
112{
113 /* Check for main structure */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114 IRDA_ASSERT(irttp->magic == TTP_MAGIC, return;);
115
116 /*
117 * Delete hashbin and close all TSAP instances in it
118 */
119 hashbin_delete(irttp->tsaps, (FREE_FUNC) __irttp_close_tsap);
120
121 irttp->magic = 0;
122
123 /* De-allocate main structure */
124 kfree(irttp);
125
126 irttp = NULL;
127}
128
129/*************************** SUBROUTINES ***************************/
130
131/*
132 * Function irttp_start_todo_timer (self, timeout)
133 *
134 * Start todo timer.
135 *
136 * Made it more effient and unsensitive to race conditions - Jean II
137 */
138static inline void irttp_start_todo_timer(struct tsap_cb *self, int timeout)
139{
140 /* Set new value for timer */
141 mod_timer(&self->todo_timer, jiffies + timeout);
142}
143
144/*
145 * Function irttp_todo_expired (data)
146 *
147 * Todo timer has expired!
148 *
149 * One of the restriction of the timer is that it is run only on the timer
150 * interrupt which run every 10ms. This mean that even if you set the timer
151 * with a delay of 0, it may take up to 10ms before it's run.
152 * So, to minimise latency and keep cache fresh, we try to avoid using
153 * it as much as possible.
154 * Note : we can't use tasklets, because they can't be asynchronously
155 * killed (need user context), and we can't guarantee that here...
156 * Jean II
157 */
158static void irttp_todo_expired(unsigned long data)
159{
160 struct tsap_cb *self = (struct tsap_cb *) data;
161
162 /* Check that we still exist */
163 if (!self || self->magic != TTP_TSAP_MAGIC)
164 return;
165
166 IRDA_DEBUG(4, "%s(instance=%p)\n", __FUNCTION__, self);
167
168 /* Try to make some progress, especially on Tx side - Jean II */
169 irttp_run_rx_queue(self);
170 irttp_run_tx_queue(self);
171
172 /* Check if time for disconnect */
173 if (test_bit(0, &self->disconnect_pend)) {
174 /* Check if it's possible to disconnect yet */
175 if (skb_queue_empty(&self->tx_queue)) {
176 /* Make sure disconnect is not pending anymore */
177 clear_bit(0, &self->disconnect_pend); /* FALSE */
178
179 /* Note : self->disconnect_skb may be NULL */
180 irttp_disconnect_request(self, self->disconnect_skb,
181 P_NORMAL);
182 self->disconnect_skb = NULL;
183 } else {
184 /* Try again later */
185 irttp_start_todo_timer(self, HZ/10);
186
187 /* No reason to try and close now */
188 return;
189 }
190 }
191
192 /* Check if it's closing time */
193 if (self->close_pend)
194 /* Finish cleanup */
195 irttp_close_tsap(self);
196}
197
198/*
199 * Function irttp_flush_queues (self)
200 *
201 * Flushes (removes all frames) in transitt-buffer (tx_list)
202 */
203void irttp_flush_queues(struct tsap_cb *self)
204{
205 struct sk_buff* skb;
206
207 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
208
209 IRDA_ASSERT(self != NULL, return;);
210 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
211
212 /* Deallocate frames waiting to be sent */
213 while ((skb = skb_dequeue(&self->tx_queue)) != NULL)
214 dev_kfree_skb(skb);
215
216 /* Deallocate received frames */
217 while ((skb = skb_dequeue(&self->rx_queue)) != NULL)
218 dev_kfree_skb(skb);
219
220 /* Deallocate received fragments */
221 while ((skb = skb_dequeue(&self->rx_fragments)) != NULL)
222 dev_kfree_skb(skb);
223}
224
225/*
226 * Function irttp_reassemble (self)
227 *
228 * Makes a new (continuous) skb of all the fragments in the fragment
229 * queue
230 *
231 */
232static struct sk_buff *irttp_reassemble_skb(struct tsap_cb *self)
233{
234 struct sk_buff *skb, *frag;
235 int n = 0; /* Fragment index */
236
237 IRDA_ASSERT(self != NULL, return NULL;);
238 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return NULL;);
239
240 IRDA_DEBUG(2, "%s(), self->rx_sdu_size=%d\n", __FUNCTION__,
241 self->rx_sdu_size);
242
243 skb = dev_alloc_skb(TTP_HEADER + self->rx_sdu_size);
244 if (!skb)
245 return NULL;
246
247 /*
248 * Need to reserve space for TTP header in case this skb needs to
249 * be requeued in case delivery failes
250 */
251 skb_reserve(skb, TTP_HEADER);
252 skb_put(skb, self->rx_sdu_size);
253
254 /*
255 * Copy all fragments to a new buffer
256 */
257 while ((frag = skb_dequeue(&self->rx_fragments)) != NULL) {
258 memcpy(skb->data+n, frag->data, frag->len);
259 n += frag->len;
260
261 dev_kfree_skb(frag);
262 }
263
264 IRDA_DEBUG(2,
265 "%s(), frame len=%d, rx_sdu_size=%d, rx_max_sdu_size=%d\n",
266 __FUNCTION__, n, self->rx_sdu_size, self->rx_max_sdu_size);
267 /* Note : irttp_run_rx_queue() calculate self->rx_sdu_size
268 * by summing the size of all fragments, so we should always
269 * have n == self->rx_sdu_size, except in cases where we
270 * droped the last fragment (when self->rx_sdu_size exceed
271 * self->rx_max_sdu_size), where n < self->rx_sdu_size.
272 * Jean II */
273 IRDA_ASSERT(n <= self->rx_sdu_size, n = self->rx_sdu_size;);
274
275 /* Set the new length */
276 skb_trim(skb, n);
277
278 self->rx_sdu_size = 0;
279
280 return skb;
281}
282
283/*
284 * Function irttp_fragment_skb (skb)
285 *
286 * Fragments a frame and queues all the fragments for transmission
287 *
288 */
289static inline void irttp_fragment_skb(struct tsap_cb *self,
290 struct sk_buff *skb)
291{
292 struct sk_buff *frag;
293 __u8 *frame;
294
295 IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
296
297 IRDA_ASSERT(self != NULL, return;);
298 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
299 IRDA_ASSERT(skb != NULL, return;);
300
301 /*
302 * Split frame into a number of segments
303 */
304 while (skb->len > self->max_seg_size) {
305 IRDA_DEBUG(2, "%s(), fragmenting ...\n", __FUNCTION__);
306
307 /* Make new segment */
Samuel Ortiz485fb2c2006-07-21 14:50:41 -0700308 frag = alloc_skb(self->max_seg_size+self->max_header_size,
309 GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310 if (!frag)
311 return;
312
313 skb_reserve(frag, self->max_header_size);
314
315 /* Copy data from the original skb into this fragment. */
316 memcpy(skb_put(frag, self->max_seg_size), skb->data,
317 self->max_seg_size);
318
319 /* Insert TTP header, with the more bit set */
320 frame = skb_push(frag, TTP_HEADER);
321 frame[0] = TTP_MORE;
322
323 /* Hide the copied data from the original skb */
324 skb_pull(skb, self->max_seg_size);
325
326 /* Queue fragment */
327 skb_queue_tail(&self->tx_queue, frag);
328 }
329 /* Queue what is left of the original skb */
330 IRDA_DEBUG(2, "%s(), queuing last segment\n", __FUNCTION__);
331
332 frame = skb_push(skb, TTP_HEADER);
333 frame[0] = 0x00; /* Clear more bit */
334
335 /* Queue fragment */
336 skb_queue_tail(&self->tx_queue, skb);
337}
338
339/*
340 * Function irttp_param_max_sdu_size (self, param)
341 *
342 * Handle the MaxSduSize parameter in the connect frames, this function
343 * will be called both when this parameter needs to be inserted into, and
344 * extracted from the connect frames
345 */
346static int irttp_param_max_sdu_size(void *instance, irda_param_t *param,
347 int get)
348{
349 struct tsap_cb *self;
350
351 self = (struct tsap_cb *) instance;
352
353 IRDA_ASSERT(self != NULL, return -1;);
354 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
355
356 if (get)
357 param->pv.i = self->tx_max_sdu_size;
358 else
359 self->tx_max_sdu_size = param->pv.i;
360
361 IRDA_DEBUG(1, "%s(), MaxSduSize=%d\n", __FUNCTION__, param->pv.i);
362
363 return 0;
364}
365
366/*************************** CLIENT CALLS ***************************/
367/************************** LMP CALLBACKS **************************/
368/* Everything is happily mixed up. Waiting for next clean up - Jean II */
369
370/*
371 * Function irttp_open_tsap (stsap, notify)
372 *
373 * Create TSAP connection endpoint,
374 */
375struct tsap_cb *irttp_open_tsap(__u8 stsap_sel, int credit, notify_t *notify)
376{
377 struct tsap_cb *self;
378 struct lsap_cb *lsap;
379 notify_t ttp_notify;
380
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381 IRDA_ASSERT(irttp->magic == TTP_MAGIC, return NULL;);
382
383 /* The IrLMP spec (IrLMP 1.1 p10) says that we have the right to
384 * use only 0x01-0x6F. Of course, we can use LSAP_ANY as well.
385 * JeanII */
386 if((stsap_sel != LSAP_ANY) &&
387 ((stsap_sel < 0x01) || (stsap_sel >= 0x70))) {
388 IRDA_DEBUG(0, "%s(), invalid tsap!\n", __FUNCTION__);
389 return NULL;
390 }
391
Panagiotis Issaris0da974f2006-07-21 14:51:30 -0700392 self = kzalloc(sizeof(struct tsap_cb), GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393 if (self == NULL) {
394 IRDA_DEBUG(0, "%s(), unable to kmalloc!\n", __FUNCTION__);
395 return NULL;
396 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397 spin_lock_init(&self->lock);
398
399 /* Initialise todo timer */
400 init_timer(&self->todo_timer);
401 self->todo_timer.data = (unsigned long) self;
402 self->todo_timer.function = &irttp_todo_expired;
403
404 /* Initialize callbacks for IrLMP to use */
405 irda_notify_init(&ttp_notify);
406 ttp_notify.connect_confirm = irttp_connect_confirm;
407 ttp_notify.connect_indication = irttp_connect_indication;
408 ttp_notify.disconnect_indication = irttp_disconnect_indication;
409 ttp_notify.data_indication = irttp_data_indication;
410 ttp_notify.udata_indication = irttp_udata_indication;
411 ttp_notify.flow_indication = irttp_flow_indication;
412 if(notify->status_indication != NULL)
413 ttp_notify.status_indication = irttp_status_indication;
414 ttp_notify.instance = self;
415 strncpy(ttp_notify.name, notify->name, NOTIFY_MAX_NAME);
416
417 self->magic = TTP_TSAP_MAGIC;
418 self->connected = FALSE;
419
420 skb_queue_head_init(&self->rx_queue);
421 skb_queue_head_init(&self->tx_queue);
422 skb_queue_head_init(&self->rx_fragments);
423 /*
424 * Create LSAP at IrLMP layer
425 */
426 lsap = irlmp_open_lsap(stsap_sel, &ttp_notify, 0);
427 if (lsap == NULL) {
428 IRDA_WARNING("%s: unable to allocate LSAP!!\n", __FUNCTION__);
429 return NULL;
430 }
431
432 /*
433 * If user specified LSAP_ANY as source TSAP selector, then IrLMP
434 * will replace it with whatever source selector which is free, so
435 * the stsap_sel we have might not be valid anymore
436 */
437 self->stsap_sel = lsap->slsap_sel;
438 IRDA_DEBUG(4, "%s(), stsap_sel=%02x\n", __FUNCTION__, self->stsap_sel);
439
440 self->notify = *notify;
441 self->lsap = lsap;
442
443 hashbin_insert(irttp->tsaps, (irda_queue_t *) self, (long) self, NULL);
444
445 if (credit > TTP_RX_MAX_CREDIT)
446 self->initial_credit = TTP_RX_MAX_CREDIT;
447 else
448 self->initial_credit = credit;
449
450 return self;
451}
452EXPORT_SYMBOL(irttp_open_tsap);
453
454/*
455 * Function irttp_close (handle)
456 *
457 * Remove an instance of a TSAP. This function should only deal with the
458 * deallocation of the TSAP, and resetting of the TSAPs values;
459 *
460 */
461static void __irttp_close_tsap(struct tsap_cb *self)
462{
463 /* First make sure we're connected. */
464 IRDA_ASSERT(self != NULL, return;);
465 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
466
467 irttp_flush_queues(self);
468
469 del_timer(&self->todo_timer);
470
471 /* This one won't be cleaned up if we are disconnect_pend + close_pend
472 * and we receive a disconnect_indication */
473 if (self->disconnect_skb)
474 dev_kfree_skb(self->disconnect_skb);
475
476 self->connected = FALSE;
477 self->magic = ~TTP_TSAP_MAGIC;
478
479 kfree(self);
480}
481
482/*
483 * Function irttp_close (self)
484 *
485 * Remove TSAP from list of all TSAPs and then deallocate all resources
486 * associated with this TSAP
487 *
488 * Note : because we *free* the tsap structure, it is the responsibility
489 * of the caller to make sure we are called only once and to deal with
490 * possible race conditions. - Jean II
491 */
492int irttp_close_tsap(struct tsap_cb *self)
493{
494 struct tsap_cb *tsap;
495
496 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
497
498 IRDA_ASSERT(self != NULL, return -1;);
499 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
500
501 /* Make sure tsap has been disconnected */
502 if (self->connected) {
503 /* Check if disconnect is not pending */
504 if (!test_bit(0, &self->disconnect_pend)) {
505 IRDA_WARNING("%s: TSAP still connected!\n",
506 __FUNCTION__);
507 irttp_disconnect_request(self, NULL, P_NORMAL);
508 }
509 self->close_pend = TRUE;
510 irttp_start_todo_timer(self, HZ/10);
511
512 return 0; /* Will be back! */
513 }
514
515 tsap = hashbin_remove(irttp->tsaps, (long) self, NULL);
516
517 IRDA_ASSERT(tsap == self, return -1;);
518
519 /* Close corresponding LSAP */
520 if (self->lsap) {
521 irlmp_close_lsap(self->lsap);
522 self->lsap = NULL;
523 }
524
525 __irttp_close_tsap(self);
526
527 return 0;
528}
529EXPORT_SYMBOL(irttp_close_tsap);
530
531/*
532 * Function irttp_udata_request (self, skb)
533 *
534 * Send unreliable data on this TSAP
535 *
536 */
537int irttp_udata_request(struct tsap_cb *self, struct sk_buff *skb)
538{
539 IRDA_ASSERT(self != NULL, return -1;);
540 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
541 IRDA_ASSERT(skb != NULL, return -1;);
542
543 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
544
545 /* Check that nothing bad happens */
546 if ((skb->len == 0) || (!self->connected)) {
547 IRDA_DEBUG(1, "%s(), No data, or not connected\n",
548 __FUNCTION__);
549 goto err;
550 }
551
552 if (skb->len > self->max_seg_size) {
553 IRDA_DEBUG(1, "%s(), UData is to large for IrLAP!\n",
554 __FUNCTION__);
555 goto err;
556 }
557
558 irlmp_udata_request(self->lsap, skb);
559 self->stats.tx_packets++;
560
561 return 0;
562
563err:
564 dev_kfree_skb(skb);
565 return -1;
566}
567EXPORT_SYMBOL(irttp_udata_request);
568
569
570/*
571 * Function irttp_data_request (handle, skb)
572 *
573 * Queue frame for transmission. If SAR is enabled, fragement the frame
574 * and queue the fragments for transmission
575 */
576int irttp_data_request(struct tsap_cb *self, struct sk_buff *skb)
577{
578 __u8 *frame;
579 int ret;
580
581 IRDA_ASSERT(self != NULL, return -1;);
582 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
583 IRDA_ASSERT(skb != NULL, return -1;);
584
585 IRDA_DEBUG(2, "%s() : queue len = %d\n", __FUNCTION__,
586 skb_queue_len(&self->tx_queue));
587
588 /* Check that nothing bad happens */
589 if ((skb->len == 0) || (!self->connected)) {
590 IRDA_WARNING("%s: No data, or not connected\n", __FUNCTION__);
591 ret = -ENOTCONN;
592 goto err;
593 }
594
595 /*
596 * Check if SAR is disabled, and the frame is larger than what fits
597 * inside an IrLAP frame
598 */
599 if ((self->tx_max_sdu_size == 0) && (skb->len > self->max_seg_size)) {
600 IRDA_ERROR("%s: SAR disabled, and data is to large for IrLAP!\n",
601 __FUNCTION__);
602 ret = -EMSGSIZE;
603 goto err;
604 }
605
606 /*
607 * Check if SAR is enabled, and the frame is larger than the
608 * TxMaxSduSize
609 */
610 if ((self->tx_max_sdu_size != 0) &&
611 (self->tx_max_sdu_size != TTP_SAR_UNBOUND) &&
612 (skb->len > self->tx_max_sdu_size))
613 {
614 IRDA_ERROR("%s: SAR enabled, but data is larger than TxMaxSduSize!\n",
615 __FUNCTION__);
616 ret = -EMSGSIZE;
617 goto err;
618 }
619 /*
620 * Check if transmit queue is full
621 */
622 if (skb_queue_len(&self->tx_queue) >= TTP_TX_MAX_QUEUE) {
623 /*
624 * Give it a chance to empty itself
625 */
626 irttp_run_tx_queue(self);
627
628 /* Drop packet. This error code should trigger the caller
629 * to resend the data in the client code - Jean II */
630 ret = -ENOBUFS;
631 goto err;
632 }
633
634 /* Queue frame, or queue frame segments */
635 if ((self->tx_max_sdu_size == 0) || (skb->len < self->max_seg_size)) {
636 /* Queue frame */
637 IRDA_ASSERT(skb_headroom(skb) >= TTP_HEADER, return -1;);
638 frame = skb_push(skb, TTP_HEADER);
639 frame[0] = 0x00; /* Clear more bit */
640
641 skb_queue_tail(&self->tx_queue, skb);
642 } else {
643 /*
644 * Fragment the frame, this function will also queue the
645 * fragments, we don't care about the fact the transmit
646 * queue may be overfilled by all the segments for a little
647 * while
648 */
649 irttp_fragment_skb(self, skb);
650 }
651
652 /* Check if we can accept more data from client */
653 if ((!self->tx_sdu_busy) &&
654 (skb_queue_len(&self->tx_queue) > TTP_TX_HIGH_THRESHOLD)) {
655 /* Tx queue filling up, so stop client. */
656 if (self->notify.flow_indication) {
657 self->notify.flow_indication(self->notify.instance,
658 self, FLOW_STOP);
659 }
660 /* self->tx_sdu_busy is the state of the client.
661 * Update state after notifying client to avoid
662 * race condition with irttp_flow_indication().
663 * If the queue empty itself after our test but before
664 * we set the flag, we will fix ourselves below in
665 * irttp_run_tx_queue().
666 * Jean II */
667 self->tx_sdu_busy = TRUE;
668 }
669
670 /* Try to make some progress */
671 irttp_run_tx_queue(self);
672
673 return 0;
674
675err:
676 dev_kfree_skb(skb);
677 return ret;
678}
679EXPORT_SYMBOL(irttp_data_request);
680
681/*
682 * Function irttp_run_tx_queue (self)
683 *
684 * Transmit packets queued for transmission (if possible)
685 *
686 */
687static void irttp_run_tx_queue(struct tsap_cb *self)
688{
689 struct sk_buff *skb;
690 unsigned long flags;
691 int n;
692
693 IRDA_DEBUG(2, "%s() : send_credit = %d, queue_len = %d\n",
694 __FUNCTION__,
695 self->send_credit, skb_queue_len(&self->tx_queue));
696
697 /* Get exclusive access to the tx queue, otherwise don't touch it */
698 if (irda_lock(&self->tx_queue_lock) == FALSE)
699 return;
700
701 /* Try to send out frames as long as we have credits
702 * and as long as LAP is not full. If LAP is full, it will
703 * poll us through irttp_flow_indication() - Jean II */
704 while ((self->send_credit > 0) &&
705 (!irlmp_lap_tx_queue_full(self->lsap)) &&
706 (skb = skb_dequeue(&self->tx_queue)))
707 {
708 /*
709 * Since we can transmit and receive frames concurrently,
710 * the code below is a critical region and we must assure that
711 * nobody messes with the credits while we update them.
712 */
713 spin_lock_irqsave(&self->lock, flags);
714
715 n = self->avail_credit;
716 self->avail_credit = 0;
717
718 /* Only room for 127 credits in frame */
719 if (n > 127) {
720 self->avail_credit = n-127;
721 n = 127;
722 }
723 self->remote_credit += n;
724 self->send_credit--;
725
726 spin_unlock_irqrestore(&self->lock, flags);
727
728 /*
729 * More bit must be set by the data_request() or fragment()
730 * functions
731 */
732 skb->data[0] |= (n & 0x7f);
733
734 /* Detach from socket.
735 * The current skb has a reference to the socket that sent
736 * it (skb->sk). When we pass it to IrLMP, the skb will be
737 * stored in in IrLAP (self->wx_list). When we are within
738 * IrLAP, we lose the notion of socket, so we should not
739 * have a reference to a socket. So, we drop it here.
740 *
741 * Why does it matter ?
742 * When the skb is freed (kfree_skb), if it is associated
743 * with a socket, it release buffer space on the socket
744 * (through sock_wfree() and sock_def_write_space()).
745 * If the socket no longer exist, we may crash. Hard.
746 * When we close a socket, we make sure that associated packets
747 * in IrTTP are freed. However, we have no way to cancel
748 * the packet that we have passed to IrLAP. So, if a packet
749 * remains in IrLAP (retry on the link or else) after we
750 * close the socket, we are dead !
751 * Jean II */
752 if (skb->sk != NULL) {
753 /* IrSOCK application, IrOBEX, ... */
754 skb_orphan(skb);
755 }
756 /* IrCOMM over IrTTP, IrLAN, ... */
757
758 /* Pass the skb to IrLMP - done */
759 irlmp_data_request(self->lsap, skb);
760 self->stats.tx_packets++;
761 }
762
763 /* Check if we can accept more frames from client.
764 * We don't want to wait until the todo timer to do that, and we
765 * can't use tasklets (grr...), so we are obliged to give control
766 * to client. That's ok, this test will be true not too often
767 * (max once per LAP window) and we are called from places
768 * where we can spend a bit of time doing stuff. - Jean II */
769 if ((self->tx_sdu_busy) &&
770 (skb_queue_len(&self->tx_queue) < TTP_TX_LOW_THRESHOLD) &&
771 (!self->close_pend))
772 {
773 if (self->notify.flow_indication)
774 self->notify.flow_indication(self->notify.instance,
775 self, FLOW_START);
776
777 /* self->tx_sdu_busy is the state of the client.
778 * We don't really have a race here, but it's always safer
779 * to update our state after the client - Jean II */
780 self->tx_sdu_busy = FALSE;
781 }
782
783 /* Reset lock */
784 self->tx_queue_lock = 0;
785}
786
787/*
788 * Function irttp_give_credit (self)
789 *
790 * Send a dataless flowdata TTP-PDU and give available credit to peer
791 * TSAP
792 */
793static inline void irttp_give_credit(struct tsap_cb *self)
794{
795 struct sk_buff *tx_skb = NULL;
796 unsigned long flags;
797 int n;
798
799 IRDA_ASSERT(self != NULL, return;);
800 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
801
802 IRDA_DEBUG(4, "%s() send=%d,avail=%d,remote=%d\n",
803 __FUNCTION__,
804 self->send_credit, self->avail_credit, self->remote_credit);
805
806 /* Give credit to peer */
Samuel Ortiz1b0fee72006-09-27 20:06:44 -0700807 tx_skb = alloc_skb(TTP_MAX_HEADER, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808 if (!tx_skb)
809 return;
810
811 /* Reserve space for LMP, and LAP header */
Samuel Ortiz1b0fee72006-09-27 20:06:44 -0700812 skb_reserve(tx_skb, LMP_MAX_HEADER);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813
814 /*
815 * Since we can transmit and receive frames concurrently,
816 * the code below is a critical region and we must assure that
817 * nobody messes with the credits while we update them.
818 */
819 spin_lock_irqsave(&self->lock, flags);
820
821 n = self->avail_credit;
822 self->avail_credit = 0;
823
824 /* Only space for 127 credits in frame */
825 if (n > 127) {
826 self->avail_credit = n - 127;
827 n = 127;
828 }
829 self->remote_credit += n;
830
831 spin_unlock_irqrestore(&self->lock, flags);
832
833 skb_put(tx_skb, 1);
834 tx_skb->data[0] = (__u8) (n & 0x7f);
835
836 irlmp_data_request(self->lsap, tx_skb);
837 self->stats.tx_packets++;
838}
839
840/*
841 * Function irttp_udata_indication (instance, sap, skb)
842 *
843 * Received some unit-data (unreliable)
844 *
845 */
846static int irttp_udata_indication(void *instance, void *sap,
847 struct sk_buff *skb)
848{
849 struct tsap_cb *self;
850 int err;
851
852 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
853
854 self = (struct tsap_cb *) instance;
855
856 IRDA_ASSERT(self != NULL, return -1;);
857 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
858 IRDA_ASSERT(skb != NULL, return -1;);
859
860 self->stats.rx_packets++;
861
862 /* Just pass data to layer above */
863 if (self->notify.udata_indication) {
864 err = self->notify.udata_indication(self->notify.instance,
865 self,skb);
866 /* Same comment as in irttp_do_data_indication() */
867 if (!err)
868 return 0;
869 }
870 /* Either no handler, or handler returns an error */
871 dev_kfree_skb(skb);
872
873 return 0;
874}
875
876/*
877 * Function irttp_data_indication (instance, sap, skb)
878 *
879 * Receive segment from IrLMP.
880 *
881 */
882static int irttp_data_indication(void *instance, void *sap,
883 struct sk_buff *skb)
884{
885 struct tsap_cb *self;
886 unsigned long flags;
887 int n;
888
889 self = (struct tsap_cb *) instance;
890
891 n = skb->data[0] & 0x7f; /* Extract the credits */
892
893 self->stats.rx_packets++;
894
895 /* Deal with inbound credit
896 * Since we can transmit and receive frames concurrently,
897 * the code below is a critical region and we must assure that
898 * nobody messes with the credits while we update them.
899 */
900 spin_lock_irqsave(&self->lock, flags);
901 self->send_credit += n;
902 if (skb->len > 1)
903 self->remote_credit--;
904 spin_unlock_irqrestore(&self->lock, flags);
905
906 /*
907 * Data or dataless packet? Dataless frames contains only the
908 * TTP_HEADER.
909 */
910 if (skb->len > 1) {
911 /*
912 * We don't remove the TTP header, since we must preserve the
913 * more bit, so the defragment routing knows what to do
914 */
915 skb_queue_tail(&self->rx_queue, skb);
916 } else {
917 /* Dataless flowdata TTP-PDU */
918 dev_kfree_skb(skb);
919 }
920
921
922 /* Push data to the higher layer.
923 * We do it synchronously because running the todo timer for each
924 * receive packet would be too much overhead and latency.
925 * By passing control to the higher layer, we run the risk that
926 * it may take time or grab a lock. Most often, the higher layer
927 * will only put packet in a queue.
928 * Anyway, packets are only dripping through the IrDA, so we can
929 * have time before the next packet.
930 * Further, we are run from NET_BH, so the worse that can happen is
931 * us missing the optimal time to send back the PF bit in LAP.
932 * Jean II */
933 irttp_run_rx_queue(self);
934
935 /* We now give credits to peer in irttp_run_rx_queue().
936 * We need to send credit *NOW*, otherwise we are going
937 * to miss the next Tx window. The todo timer may take
938 * a while before it's run... - Jean II */
939
940 /*
941 * If the peer device has given us some credits and we didn't have
942 * anyone from before, then we need to shedule the tx queue.
943 * We need to do that because our Tx have stopped (so we may not
944 * get any LAP flow indication) and the user may be stopped as
945 * well. - Jean II
946 */
947 if (self->send_credit == n) {
948 /* Restart pushing stuff to LAP */
949 irttp_run_tx_queue(self);
950 /* Note : we don't want to schedule the todo timer
951 * because it has horrible latency. No tasklets
952 * because the tasklet API is broken. - Jean II */
953 }
954
955 return 0;
956}
957
958/*
959 * Function irttp_status_indication (self, reason)
960 *
961 * Status_indication, just pass to the higher layer...
962 *
963 */
964static void irttp_status_indication(void *instance,
965 LINK_STATUS link, LOCK_STATUS lock)
966{
967 struct tsap_cb *self;
968
969 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
970
971 self = (struct tsap_cb *) instance;
972
973 IRDA_ASSERT(self != NULL, return;);
974 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
975
976 /* Check if client has already closed the TSAP and gone away */
977 if (self->close_pend)
978 return;
979
980 /*
981 * Inform service user if he has requested it
982 */
983 if (self->notify.status_indication != NULL)
984 self->notify.status_indication(self->notify.instance,
985 link, lock);
986 else
987 IRDA_DEBUG(2, "%s(), no handler\n", __FUNCTION__);
988}
989
990/*
991 * Function irttp_flow_indication (self, reason)
992 *
993 * Flow_indication : IrLAP tells us to send more data.
994 *
995 */
996static void irttp_flow_indication(void *instance, void *sap, LOCAL_FLOW flow)
997{
998 struct tsap_cb *self;
999
1000 self = (struct tsap_cb *) instance;
1001
1002 IRDA_ASSERT(self != NULL, return;);
1003 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1004
1005 IRDA_DEBUG(4, "%s(instance=%p)\n", __FUNCTION__, self);
1006
1007 /* We are "polled" directly from LAP, and the LAP want to fill
1008 * its Tx window. We want to do our best to send it data, so that
1009 * we maximise the window. On the other hand, we want to limit the
1010 * amount of work here so that LAP doesn't hang forever waiting
1011 * for packets. - Jean II */
1012
1013 /* Try to send some packets. Currently, LAP calls us every time
1014 * there is one free slot, so we will send only one packet.
1015 * This allow the scheduler to do its round robin - Jean II */
1016 irttp_run_tx_queue(self);
1017
1018 /* Note regarding the interraction with higher layer.
1019 * irttp_run_tx_queue() may call the client when its queue
1020 * start to empty, via notify.flow_indication(). Initially.
1021 * I wanted this to happen in a tasklet, to avoid client
1022 * grabbing the CPU, but we can't use tasklets safely. And timer
1023 * is definitely too slow.
1024 * This will happen only once per LAP window, and usually at
1025 * the third packet (unless window is smaller). LAP is still
1026 * doing mtt and sending first packet so it's sort of OK
1027 * to do that. Jean II */
1028
1029 /* If we need to send disconnect. try to do it now */
1030 if(self->disconnect_pend)
1031 irttp_start_todo_timer(self, 0);
1032}
1033
1034/*
1035 * Function irttp_flow_request (self, command)
1036 *
1037 * This function could be used by the upper layers to tell IrTTP to stop
1038 * delivering frames if the receive queues are starting to get full, or
1039 * to tell IrTTP to start delivering frames again.
1040 */
1041void irttp_flow_request(struct tsap_cb *self, LOCAL_FLOW flow)
1042{
1043 IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
1044
1045 IRDA_ASSERT(self != NULL, return;);
1046 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1047
1048 switch (flow) {
1049 case FLOW_STOP:
1050 IRDA_DEBUG(1, "%s(), flow stop\n", __FUNCTION__);
1051 self->rx_sdu_busy = TRUE;
1052 break;
1053 case FLOW_START:
1054 IRDA_DEBUG(1, "%s(), flow start\n", __FUNCTION__);
1055 self->rx_sdu_busy = FALSE;
1056
1057 /* Client say he can accept more data, try to free our
1058 * queues ASAP - Jean II */
1059 irttp_run_rx_queue(self);
1060
1061 break;
1062 default:
1063 IRDA_DEBUG(1, "%s(), Unknown flow command!\n", __FUNCTION__);
1064 }
1065}
1066EXPORT_SYMBOL(irttp_flow_request);
1067
1068/*
1069 * Function irttp_connect_request (self, dtsap_sel, daddr, qos)
1070 *
1071 * Try to connect to remote destination TSAP selector
1072 *
1073 */
1074int irttp_connect_request(struct tsap_cb *self, __u8 dtsap_sel,
1075 __u32 saddr, __u32 daddr,
1076 struct qos_info *qos, __u32 max_sdu_size,
1077 struct sk_buff *userdata)
1078{
1079 struct sk_buff *tx_skb;
1080 __u8 *frame;
1081 __u8 n;
1082
1083 IRDA_DEBUG(4, "%s(), max_sdu_size=%d\n", __FUNCTION__, max_sdu_size);
1084
1085 IRDA_ASSERT(self != NULL, return -EBADR;);
1086 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -EBADR;);
1087
1088 if (self->connected) {
1089 if(userdata)
1090 dev_kfree_skb(userdata);
1091 return -EISCONN;
1092 }
1093
1094 /* Any userdata supplied? */
1095 if (userdata == NULL) {
Samuel Ortiz1b0fee72006-09-27 20:06:44 -07001096 tx_skb = alloc_skb(TTP_MAX_HEADER + TTP_SAR_HEADER,
1097 GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001098 if (!tx_skb)
1099 return -ENOMEM;
1100
1101 /* Reserve space for MUX_CONTROL and LAP header */
1102 skb_reserve(tx_skb, TTP_MAX_HEADER);
1103 } else {
1104 tx_skb = userdata;
1105 /*
1106 * Check that the client has reserved enough space for
1107 * headers
1108 */
1109 IRDA_ASSERT(skb_headroom(userdata) >= TTP_MAX_HEADER,
1110 { dev_kfree_skb(userdata); return -1; } );
1111 }
1112
1113 /* Initialize connection parameters */
1114 self->connected = FALSE;
1115 self->avail_credit = 0;
1116 self->rx_max_sdu_size = max_sdu_size;
1117 self->rx_sdu_size = 0;
1118 self->rx_sdu_busy = FALSE;
1119 self->dtsap_sel = dtsap_sel;
1120
1121 n = self->initial_credit;
1122
1123 self->remote_credit = 0;
1124 self->send_credit = 0;
1125
1126 /*
1127 * Give away max 127 credits for now
1128 */
1129 if (n > 127) {
1130 self->avail_credit=n-127;
1131 n = 127;
1132 }
1133
1134 self->remote_credit = n;
1135
1136 /* SAR enabled? */
1137 if (max_sdu_size > 0) {
1138 IRDA_ASSERT(skb_headroom(tx_skb) >= (TTP_MAX_HEADER + TTP_SAR_HEADER),
1139 { dev_kfree_skb(tx_skb); return -1; } );
1140
1141 /* Insert SAR parameters */
1142 frame = skb_push(tx_skb, TTP_HEADER+TTP_SAR_HEADER);
1143
1144 frame[0] = TTP_PARAMETERS | n;
1145 frame[1] = 0x04; /* Length */
1146 frame[2] = 0x01; /* MaxSduSize */
1147 frame[3] = 0x02; /* Value length */
1148
1149 put_unaligned(cpu_to_be16((__u16) max_sdu_size),
Al Viro448c31a2006-11-14 20:47:46 -08001150 (__be16 *)(frame+4));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001151 } else {
1152 /* Insert plain TTP header */
1153 frame = skb_push(tx_skb, TTP_HEADER);
1154
1155 /* Insert initial credit in frame */
1156 frame[0] = n & 0x7f;
1157 }
1158
1159 /* Connect with IrLMP. No QoS parameters for now */
1160 return irlmp_connect_request(self->lsap, dtsap_sel, saddr, daddr, qos,
1161 tx_skb);
1162}
1163EXPORT_SYMBOL(irttp_connect_request);
1164
1165/*
1166 * Function irttp_connect_confirm (handle, qos, skb)
1167 *
1168 * Sevice user confirms TSAP connection with peer.
1169 *
1170 */
1171static void irttp_connect_confirm(void *instance, void *sap,
1172 struct qos_info *qos, __u32 max_seg_size,
1173 __u8 max_header_size, struct sk_buff *skb)
1174{
1175 struct tsap_cb *self;
1176 int parameters;
1177 int ret;
1178 __u8 plen;
1179 __u8 n;
1180
1181 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
1182
1183 self = (struct tsap_cb *) instance;
1184
1185 IRDA_ASSERT(self != NULL, return;);
1186 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1187 IRDA_ASSERT(skb != NULL, return;);
1188
1189 self->max_seg_size = max_seg_size - TTP_HEADER;
1190 self->max_header_size = max_header_size + TTP_HEADER;
1191
1192 /*
1193 * Check if we have got some QoS parameters back! This should be the
1194 * negotiated QoS for the link.
1195 */
1196 if (qos) {
1197 IRDA_DEBUG(4, "IrTTP, Negotiated BAUD_RATE: %02x\n",
1198 qos->baud_rate.bits);
1199 IRDA_DEBUG(4, "IrTTP, Negotiated BAUD_RATE: %d bps.\n",
1200 qos->baud_rate.value);
1201 }
1202
1203 n = skb->data[0] & 0x7f;
1204
1205 IRDA_DEBUG(4, "%s(), Initial send_credit=%d\n", __FUNCTION__, n);
1206
1207 self->send_credit = n;
1208 self->tx_max_sdu_size = 0;
1209 self->connected = TRUE;
1210
1211 parameters = skb->data[0] & 0x80;
1212
1213 IRDA_ASSERT(skb->len >= TTP_HEADER, return;);
1214 skb_pull(skb, TTP_HEADER);
1215
1216 if (parameters) {
1217 plen = skb->data[0];
1218
1219 ret = irda_param_extract_all(self, skb->data+1,
1220 IRDA_MIN(skb->len-1, plen),
1221 &param_info);
1222
1223 /* Any errors in the parameter list? */
1224 if (ret < 0) {
1225 IRDA_WARNING("%s: error extracting parameters\n",
1226 __FUNCTION__);
1227 dev_kfree_skb(skb);
1228
1229 /* Do not accept this connection attempt */
1230 return;
1231 }
1232 /* Remove parameters */
1233 skb_pull(skb, IRDA_MIN(skb->len, plen+1));
1234 }
1235
1236 IRDA_DEBUG(4, "%s() send=%d,avail=%d,remote=%d\n", __FUNCTION__,
1237 self->send_credit, self->avail_credit, self->remote_credit);
1238
1239 IRDA_DEBUG(2, "%s(), MaxSduSize=%d\n", __FUNCTION__,
1240 self->tx_max_sdu_size);
1241
1242 if (self->notify.connect_confirm) {
1243 self->notify.connect_confirm(self->notify.instance, self, qos,
1244 self->tx_max_sdu_size,
1245 self->max_header_size, skb);
1246 } else
1247 dev_kfree_skb(skb);
1248}
1249
1250/*
1251 * Function irttp_connect_indication (handle, skb)
1252 *
1253 * Some other device is connecting to this TSAP
1254 *
1255 */
1256void irttp_connect_indication(void *instance, void *sap, struct qos_info *qos,
1257 __u32 max_seg_size, __u8 max_header_size,
1258 struct sk_buff *skb)
1259{
1260 struct tsap_cb *self;
1261 struct lsap_cb *lsap;
1262 int parameters;
1263 int ret;
1264 __u8 plen;
1265 __u8 n;
1266
1267 self = (struct tsap_cb *) instance;
1268
1269 IRDA_ASSERT(self != NULL, return;);
1270 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1271 IRDA_ASSERT(skb != NULL, return;);
1272
1273 lsap = (struct lsap_cb *) sap;
1274
1275 self->max_seg_size = max_seg_size - TTP_HEADER;
1276 self->max_header_size = max_header_size+TTP_HEADER;
1277
1278 IRDA_DEBUG(4, "%s(), TSAP sel=%02x\n", __FUNCTION__, self->stsap_sel);
1279
1280 /* Need to update dtsap_sel if its equal to LSAP_ANY */
1281 self->dtsap_sel = lsap->dlsap_sel;
1282
1283 n = skb->data[0] & 0x7f;
1284
1285 self->send_credit = n;
1286 self->tx_max_sdu_size = 0;
1287
1288 parameters = skb->data[0] & 0x80;
1289
1290 IRDA_ASSERT(skb->len >= TTP_HEADER, return;);
1291 skb_pull(skb, TTP_HEADER);
1292
1293 if (parameters) {
1294 plen = skb->data[0];
1295
1296 ret = irda_param_extract_all(self, skb->data+1,
1297 IRDA_MIN(skb->len-1, plen),
1298 &param_info);
1299
1300 /* Any errors in the parameter list? */
1301 if (ret < 0) {
1302 IRDA_WARNING("%s: error extracting parameters\n",
1303 __FUNCTION__);
1304 dev_kfree_skb(skb);
1305
1306 /* Do not accept this connection attempt */
1307 return;
1308 }
1309
1310 /* Remove parameters */
1311 skb_pull(skb, IRDA_MIN(skb->len, plen+1));
1312 }
1313
1314 if (self->notify.connect_indication) {
1315 self->notify.connect_indication(self->notify.instance, self,
1316 qos, self->tx_max_sdu_size,
1317 self->max_header_size, skb);
1318 } else
1319 dev_kfree_skb(skb);
1320}
1321
1322/*
1323 * Function irttp_connect_response (handle, userdata)
1324 *
1325 * Service user is accepting the connection, just pass it down to
1326 * IrLMP!
1327 *
1328 */
1329int irttp_connect_response(struct tsap_cb *self, __u32 max_sdu_size,
1330 struct sk_buff *userdata)
1331{
1332 struct sk_buff *tx_skb;
1333 __u8 *frame;
1334 int ret;
1335 __u8 n;
1336
1337 IRDA_ASSERT(self != NULL, return -1;);
1338 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
1339
1340 IRDA_DEBUG(4, "%s(), Source TSAP selector=%02x\n", __FUNCTION__,
1341 self->stsap_sel);
1342
1343 /* Any userdata supplied? */
1344 if (userdata == NULL) {
Samuel Ortiz1b0fee72006-09-27 20:06:44 -07001345 tx_skb = alloc_skb(TTP_MAX_HEADER + TTP_SAR_HEADER,
1346 GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001347 if (!tx_skb)
1348 return -ENOMEM;
1349
1350 /* Reserve space for MUX_CONTROL and LAP header */
1351 skb_reserve(tx_skb, TTP_MAX_HEADER);
1352 } else {
1353 tx_skb = userdata;
1354 /*
1355 * Check that the client has reserved enough space for
1356 * headers
1357 */
1358 IRDA_ASSERT(skb_headroom(userdata) >= TTP_MAX_HEADER,
1359 { dev_kfree_skb(userdata); return -1; } );
1360 }
1361
1362 self->avail_credit = 0;
1363 self->remote_credit = 0;
1364 self->rx_max_sdu_size = max_sdu_size;
1365 self->rx_sdu_size = 0;
1366 self->rx_sdu_busy = FALSE;
1367
1368 n = self->initial_credit;
1369
1370 /* Frame has only space for max 127 credits (7 bits) */
1371 if (n > 127) {
1372 self->avail_credit = n - 127;
1373 n = 127;
1374 }
1375
1376 self->remote_credit = n;
1377 self->connected = TRUE;
1378
1379 /* SAR enabled? */
1380 if (max_sdu_size > 0) {
1381 IRDA_ASSERT(skb_headroom(tx_skb) >= (TTP_MAX_HEADER + TTP_SAR_HEADER),
1382 { dev_kfree_skb(tx_skb); return -1; } );
1383
1384 /* Insert TTP header with SAR parameters */
1385 frame = skb_push(tx_skb, TTP_HEADER+TTP_SAR_HEADER);
1386
1387 frame[0] = TTP_PARAMETERS | n;
1388 frame[1] = 0x04; /* Length */
1389
1390 /* irda_param_insert(self, IRTTP_MAX_SDU_SIZE, frame+1, */
1391/* TTP_SAR_HEADER, &param_info) */
1392
1393 frame[2] = 0x01; /* MaxSduSize */
1394 frame[3] = 0x02; /* Value length */
1395
1396 put_unaligned(cpu_to_be16((__u16) max_sdu_size),
Al Viro448c31a2006-11-14 20:47:46 -08001397 (__be16 *)(frame+4));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001398 } else {
1399 /* Insert TTP header */
1400 frame = skb_push(tx_skb, TTP_HEADER);
1401
1402 frame[0] = n & 0x7f;
1403 }
1404
1405 ret = irlmp_connect_response(self->lsap, tx_skb);
1406
1407 return ret;
1408}
1409EXPORT_SYMBOL(irttp_connect_response);
1410
1411/*
1412 * Function irttp_dup (self, instance)
1413 *
1414 * Duplicate TSAP, can be used by servers to confirm a connection on a
1415 * new TSAP so it can keep listening on the old one.
1416 */
1417struct tsap_cb *irttp_dup(struct tsap_cb *orig, void *instance)
1418{
1419 struct tsap_cb *new;
1420 unsigned long flags;
1421
1422 IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
1423
1424 /* Protect our access to the old tsap instance */
1425 spin_lock_irqsave(&irttp->tsaps->hb_spinlock, flags);
1426
1427 /* Find the old instance */
1428 if (!hashbin_find(irttp->tsaps, (long) orig, NULL)) {
1429 IRDA_DEBUG(0, "%s(), unable to find TSAP\n", __FUNCTION__);
1430 spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
1431 return NULL;
1432 }
1433
1434 /* Allocate a new instance */
1435 new = kmalloc(sizeof(struct tsap_cb), GFP_ATOMIC);
1436 if (!new) {
1437 IRDA_DEBUG(0, "%s(), unable to kmalloc\n", __FUNCTION__);
1438 spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
1439 return NULL;
1440 }
1441 /* Dup */
1442 memcpy(new, orig, sizeof(struct tsap_cb));
1443
1444 /* We don't need the old instance any more */
1445 spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
1446
1447 /* Try to dup the LSAP (may fail if we were too slow) */
1448 new->lsap = irlmp_dup(orig->lsap, new);
1449 if (!new->lsap) {
1450 IRDA_DEBUG(0, "%s(), dup failed!\n", __FUNCTION__);
1451 kfree(new);
1452 return NULL;
1453 }
1454
1455 /* Not everything should be copied */
1456 new->notify.instance = instance;
1457 init_timer(&new->todo_timer);
1458
1459 skb_queue_head_init(&new->rx_queue);
1460 skb_queue_head_init(&new->tx_queue);
1461 skb_queue_head_init(&new->rx_fragments);
1462
1463 /* This is locked */
1464 hashbin_insert(irttp->tsaps, (irda_queue_t *) new, (long) new, NULL);
1465
1466 return new;
1467}
1468EXPORT_SYMBOL(irttp_dup);
1469
1470/*
1471 * Function irttp_disconnect_request (self)
1472 *
1473 * Close this connection please! If priority is high, the queued data
1474 * segments, if any, will be deallocated first
1475 *
1476 */
1477int irttp_disconnect_request(struct tsap_cb *self, struct sk_buff *userdata,
1478 int priority)
1479{
1480 int ret;
1481
1482 IRDA_ASSERT(self != NULL, return -1;);
1483 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
1484
1485 /* Already disconnected? */
1486 if (!self->connected) {
1487 IRDA_DEBUG(4, "%s(), already disconnected!\n", __FUNCTION__);
1488 if (userdata)
1489 dev_kfree_skb(userdata);
1490 return -1;
1491 }
1492
1493 /* Disconnect already pending ?
1494 * We need to use an atomic operation to prevent reentry. This
1495 * function may be called from various context, like user, timer
1496 * for following a disconnect_indication() (i.e. net_bh).
1497 * Jean II */
1498 if(test_and_set_bit(0, &self->disconnect_pend)) {
1499 IRDA_DEBUG(0, "%s(), disconnect already pending\n",
1500 __FUNCTION__);
1501 if (userdata)
1502 dev_kfree_skb(userdata);
1503
1504 /* Try to make some progress */
1505 irttp_run_tx_queue(self);
1506 return -1;
1507 }
1508
1509 /*
1510 * Check if there is still data segments in the transmit queue
1511 */
David S. Millerb03efcf2005-07-08 14:57:23 -07001512 if (!skb_queue_empty(&self->tx_queue)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001513 if (priority == P_HIGH) {
1514 /*
1515 * No need to send the queued data, if we are
1516 * disconnecting right now since the data will
1517 * not have any usable connection to be sent on
1518 */
1519 IRDA_DEBUG(1, "%s(): High priority!!()\n", __FUNCTION__);
1520 irttp_flush_queues(self);
1521 } else if (priority == P_NORMAL) {
1522 /*
1523 * Must delay disconnect until after all data segments
1524 * have been sent and the tx_queue is empty
1525 */
1526 /* We'll reuse this one later for the disconnect */
1527 self->disconnect_skb = userdata; /* May be NULL */
1528
1529 irttp_run_tx_queue(self);
1530
1531 irttp_start_todo_timer(self, HZ/10);
1532 return -1;
1533 }
1534 }
1535 /* Note : we don't need to check if self->rx_queue is full and the
1536 * state of self->rx_sdu_busy because the disconnect response will
1537 * be sent at the LMP level (so even if the peer has its Tx queue
1538 * full of data). - Jean II */
1539
1540 IRDA_DEBUG(1, "%s(), Disconnecting ...\n", __FUNCTION__);
1541 self->connected = FALSE;
1542
1543 if (!userdata) {
1544 struct sk_buff *tx_skb;
Samuel Ortiz1b0fee72006-09-27 20:06:44 -07001545 tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001546 if (!tx_skb)
1547 return -ENOMEM;
1548
1549 /*
1550 * Reserve space for MUX and LAP header
1551 */
Samuel Ortiz1b0fee72006-09-27 20:06:44 -07001552 skb_reserve(tx_skb, LMP_MAX_HEADER);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001553
1554 userdata = tx_skb;
1555 }
1556 ret = irlmp_disconnect_request(self->lsap, userdata);
1557
1558 /* The disconnect is no longer pending */
1559 clear_bit(0, &self->disconnect_pend); /* FALSE */
1560
1561 return ret;
1562}
1563EXPORT_SYMBOL(irttp_disconnect_request);
1564
1565/*
1566 * Function irttp_disconnect_indication (self, reason)
1567 *
1568 * Disconnect indication, TSAP disconnected by peer?
1569 *
1570 */
1571void irttp_disconnect_indication(void *instance, void *sap, LM_REASON reason,
1572 struct sk_buff *skb)
1573{
1574 struct tsap_cb *self;
1575
1576 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
1577
1578 self = (struct tsap_cb *) instance;
1579
1580 IRDA_ASSERT(self != NULL, return;);
1581 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1582
1583 /* Prevent higher layer to send more data */
1584 self->connected = FALSE;
1585
1586 /* Check if client has already tried to close the TSAP */
1587 if (self->close_pend) {
1588 /* In this case, the higher layer is probably gone. Don't
1589 * bother it and clean up the remains - Jean II */
1590 if (skb)
1591 dev_kfree_skb(skb);
1592 irttp_close_tsap(self);
1593 return;
1594 }
1595
1596 /* If we are here, we assume that is the higher layer is still
1597 * waiting for the disconnect notification and able to process it,
1598 * even if he tried to disconnect. Otherwise, it would have already
1599 * attempted to close the tsap and self->close_pend would be TRUE.
1600 * Jean II */
1601
1602 /* No need to notify the client if has already tried to disconnect */
1603 if(self->notify.disconnect_indication)
1604 self->notify.disconnect_indication(self->notify.instance, self,
1605 reason, skb);
1606 else
1607 if (skb)
1608 dev_kfree_skb(skb);
1609}
1610
1611/*
1612 * Function irttp_do_data_indication (self, skb)
1613 *
1614 * Try to deliver reassembled skb to layer above, and requeue it if that
1615 * for some reason should fail. We mark rx sdu as busy to apply back
1616 * pressure is necessary.
1617 */
1618static void irttp_do_data_indication(struct tsap_cb *self, struct sk_buff *skb)
1619{
1620 int err;
1621
1622 /* Check if client has already closed the TSAP and gone away */
1623 if (self->close_pend) {
1624 dev_kfree_skb(skb);
1625 return;
1626 }
1627
1628 err = self->notify.data_indication(self->notify.instance, self, skb);
1629
1630 /* Usually the layer above will notify that it's input queue is
1631 * starting to get filled by using the flow request, but this may
1632 * be difficult, so it can instead just refuse to eat it and just
1633 * give an error back
1634 */
1635 if (err) {
1636 IRDA_DEBUG(0, "%s() requeueing skb!\n", __FUNCTION__);
1637
1638 /* Make sure we take a break */
1639 self->rx_sdu_busy = TRUE;
1640
1641 /* Need to push the header in again */
1642 skb_push(skb, TTP_HEADER);
1643 skb->data[0] = 0x00; /* Make sure MORE bit is cleared */
1644
1645 /* Put skb back on queue */
1646 skb_queue_head(&self->rx_queue, skb);
1647 }
1648}
1649
1650/*
1651 * Function irttp_run_rx_queue (self)
1652 *
1653 * Check if we have any frames to be transmitted, or if we have any
1654 * available credit to give away.
1655 */
1656void irttp_run_rx_queue(struct tsap_cb *self)
1657{
1658 struct sk_buff *skb;
1659 int more = 0;
1660
1661 IRDA_DEBUG(2, "%s() send=%d,avail=%d,remote=%d\n", __FUNCTION__,
1662 self->send_credit, self->avail_credit, self->remote_credit);
1663
1664 /* Get exclusive access to the rx queue, otherwise don't touch it */
1665 if (irda_lock(&self->rx_queue_lock) == FALSE)
1666 return;
1667
1668 /*
1669 * Reassemble all frames in receive queue and deliver them
1670 */
1671 while (!self->rx_sdu_busy && (skb = skb_dequeue(&self->rx_queue))) {
1672 /* This bit will tell us if it's the last fragment or not */
1673 more = skb->data[0] & 0x80;
1674
1675 /* Remove TTP header */
1676 skb_pull(skb, TTP_HEADER);
1677
1678 /* Add the length of the remaining data */
1679 self->rx_sdu_size += skb->len;
1680
1681 /*
1682 * If SAR is disabled, or user has requested no reassembly
1683 * of received fragments then we just deliver them
1684 * immediately. This can be requested by clients that
1685 * implements byte streams without any message boundaries
1686 */
1687 if (self->rx_max_sdu_size == TTP_SAR_DISABLE) {
1688 irttp_do_data_indication(self, skb);
1689 self->rx_sdu_size = 0;
1690
1691 continue;
1692 }
1693
1694 /* Check if this is a fragment, and not the last fragment */
1695 if (more) {
1696 /*
1697 * Queue the fragment if we still are within the
1698 * limits of the maximum size of the rx_sdu
1699 */
1700 if (self->rx_sdu_size <= self->rx_max_sdu_size) {
1701 IRDA_DEBUG(4, "%s(), queueing frag\n",
1702 __FUNCTION__);
1703 skb_queue_tail(&self->rx_fragments, skb);
1704 } else {
1705 /* Free the part of the SDU that is too big */
1706 dev_kfree_skb(skb);
1707 }
1708 continue;
1709 }
1710 /*
1711 * This is the last fragment, so time to reassemble!
1712 */
1713 if ((self->rx_sdu_size <= self->rx_max_sdu_size) ||
1714 (self->rx_max_sdu_size == TTP_SAR_UNBOUND))
1715 {
1716 /*
1717 * A little optimizing. Only queue the fragment if
1718 * there are other fragments. Since if this is the
1719 * last and only fragment, there is no need to
1720 * reassemble :-)
1721 */
1722 if (!skb_queue_empty(&self->rx_fragments)) {
1723 skb_queue_tail(&self->rx_fragments,
1724 skb);
1725
1726 skb = irttp_reassemble_skb(self);
1727 }
1728
1729 /* Now we can deliver the reassembled skb */
1730 irttp_do_data_indication(self, skb);
1731 } else {
1732 IRDA_DEBUG(1, "%s(), Truncated frame\n", __FUNCTION__);
1733
1734 /* Free the part of the SDU that is too big */
1735 dev_kfree_skb(skb);
1736
1737 /* Deliver only the valid but truncated part of SDU */
1738 skb = irttp_reassemble_skb(self);
1739
1740 irttp_do_data_indication(self, skb);
1741 }
1742 self->rx_sdu_size = 0;
1743 }
1744
1745 /*
1746 * It's not trivial to keep track of how many credits are available
1747 * by incrementing at each packet, because delivery may fail
1748 * (irttp_do_data_indication() may requeue the frame) and because
1749 * we need to take care of fragmentation.
1750 * We want the other side to send up to initial_credit packets.
1751 * We have some frames in our queues, and we have already allowed it
1752 * to send remote_credit.
1753 * No need to spinlock, write is atomic and self correcting...
1754 * Jean II
1755 */
1756 self->avail_credit = (self->initial_credit -
1757 (self->remote_credit +
1758 skb_queue_len(&self->rx_queue) +
1759 skb_queue_len(&self->rx_fragments)));
1760
1761 /* Do we have too much credits to send to peer ? */
1762 if ((self->remote_credit <= TTP_RX_MIN_CREDIT) &&
1763 (self->avail_credit > 0)) {
1764 /* Send explicit credit frame */
1765 irttp_give_credit(self);
1766 /* Note : do *NOT* check if tx_queue is non-empty, that
1767 * will produce deadlocks. I repeat : send a credit frame
1768 * even if we have something to send in our Tx queue.
1769 * If we have credits, it means that our Tx queue is blocked.
1770 *
1771 * Let's suppose the peer can't keep up with our Tx. He will
1772 * flow control us by not sending us any credits, and we
1773 * will stop Tx and start accumulating credits here.
1774 * Up to the point where the peer will stop its Tx queue,
1775 * for lack of credits.
1776 * Let's assume the peer application is single threaded.
1777 * It will block on Tx and never consume any Rx buffer.
1778 * Deadlock. Guaranteed. - Jean II
1779 */
1780 }
1781
1782 /* Reset lock */
1783 self->rx_queue_lock = 0;
1784}
1785
1786#ifdef CONFIG_PROC_FS
1787struct irttp_iter_state {
1788 int id;
1789};
1790
1791static void *irttp_seq_start(struct seq_file *seq, loff_t *pos)
1792{
1793 struct irttp_iter_state *iter = seq->private;
1794 struct tsap_cb *self;
1795
1796 /* Protect our access to the tsap list */
1797 spin_lock_irq(&irttp->tsaps->hb_spinlock);
1798 iter->id = 0;
1799
1800 for (self = (struct tsap_cb *) hashbin_get_first(irttp->tsaps);
1801 self != NULL;
1802 self = (struct tsap_cb *) hashbin_get_next(irttp->tsaps)) {
1803 if (iter->id == *pos)
1804 break;
1805 ++iter->id;
1806 }
1807
1808 return self;
1809}
1810
1811static void *irttp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1812{
1813 struct irttp_iter_state *iter = seq->private;
1814
1815 ++*pos;
1816 ++iter->id;
1817 return (void *) hashbin_get_next(irttp->tsaps);
1818}
1819
1820static void irttp_seq_stop(struct seq_file *seq, void *v)
1821{
1822 spin_unlock_irq(&irttp->tsaps->hb_spinlock);
1823}
1824
1825static int irttp_seq_show(struct seq_file *seq, void *v)
1826{
1827 const struct irttp_iter_state *iter = seq->private;
1828 const struct tsap_cb *self = v;
1829
1830 seq_printf(seq, "TSAP %d, ", iter->id);
1831 seq_printf(seq, "stsap_sel: %02x, ",
1832 self->stsap_sel);
1833 seq_printf(seq, "dtsap_sel: %02x\n",
1834 self->dtsap_sel);
1835 seq_printf(seq, " connected: %s, ",
1836 self->connected? "TRUE":"FALSE");
1837 seq_printf(seq, "avail credit: %d, ",
1838 self->avail_credit);
1839 seq_printf(seq, "remote credit: %d, ",
1840 self->remote_credit);
1841 seq_printf(seq, "send credit: %d\n",
1842 self->send_credit);
1843 seq_printf(seq, " tx packets: %ld, ",
1844 self->stats.tx_packets);
1845 seq_printf(seq, "rx packets: %ld, ",
1846 self->stats.rx_packets);
1847 seq_printf(seq, "tx_queue len: %d ",
1848 skb_queue_len(&self->tx_queue));
1849 seq_printf(seq, "rx_queue len: %d\n",
1850 skb_queue_len(&self->rx_queue));
1851 seq_printf(seq, " tx_sdu_busy: %s, ",
1852 self->tx_sdu_busy? "TRUE":"FALSE");
1853 seq_printf(seq, "rx_sdu_busy: %s\n",
1854 self->rx_sdu_busy? "TRUE":"FALSE");
1855 seq_printf(seq, " max_seg_size: %d, ",
1856 self->max_seg_size);
1857 seq_printf(seq, "tx_max_sdu_size: %d, ",
1858 self->tx_max_sdu_size);
1859 seq_printf(seq, "rx_max_sdu_size: %d\n",
1860 self->rx_max_sdu_size);
1861
1862 seq_printf(seq, " Used by (%s)\n\n",
1863 self->notify.name);
1864 return 0;
1865}
1866
1867static struct seq_operations irttp_seq_ops = {
1868 .start = irttp_seq_start,
1869 .next = irttp_seq_next,
1870 .stop = irttp_seq_stop,
1871 .show = irttp_seq_show,
1872};
1873
1874static int irttp_seq_open(struct inode *inode, struct file *file)
1875{
1876 struct seq_file *seq;
1877 int rc = -ENOMEM;
1878 struct irttp_iter_state *s;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001879
Panagiotis Issaris0da974f2006-07-21 14:51:30 -07001880 s = kzalloc(sizeof(*s), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001881 if (!s)
1882 goto out;
1883
1884 rc = seq_open(file, &irttp_seq_ops);
1885 if (rc)
1886 goto out_kfree;
1887
1888 seq = file->private_data;
1889 seq->private = s;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001890out:
1891 return rc;
1892out_kfree:
1893 kfree(s);
1894 goto out;
1895}
1896
1897struct file_operations irttp_seq_fops = {
1898 .owner = THIS_MODULE,
1899 .open = irttp_seq_open,
1900 .read = seq_read,
1901 .llseek = seq_lseek,
1902 .release = seq_release_private,
1903};
1904
1905#endif /* PROC_FS */