aboutsummaryrefslogtreecommitdiffstats
path: root/net/irda/irttp.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/irda/irttp.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'net/irda/irttp.c')
-rw-r--r--net/irda/irttp.c1912
1 files changed, 1912 insertions, 0 deletions
diff --git a/net/irda/irttp.c b/net/irda/irttp.c
new file mode 100644
index 000000000000..d091ccf773b3
--- /dev/null
+++ b/net/irda/irttp.c
@@ -0,0 +1,1912 @@
1/*********************************************************************
2 *
3 * Filename: irttp.c
4 * Version: 1.2
5 * Description: Tiny Transport Protocol (TTP) implementation
6 * Status: Stable
7 * Author: Dag Brattli <dagb@cs.uit.no>
8 * Created at: Sun Aug 31 20:14:31 1997
9 * Modified at: Wed Jan 5 11:31:27 2000
10 * Modified by: Dag Brattli <dagb@cs.uit.no>
11 *
12 * Copyright (c) 1998-2000 Dag Brattli <dagb@cs.uit.no>,
13 * All Rights Reserved.
14 * Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com>
15 *
16 * This program is free software; you can redistribute it and/or
17 * modify it under the terms of the GNU General Public License as
18 * published by the Free Software Foundation; either version 2 of
19 * the License, or (at your option) any later version.
20 *
21 * Neither Dag Brattli nor University of Tromsų admit liability nor
22 * provide warranty for any of this software. This material is
23 * provided "AS-IS" and at no charge.
24 *
25 ********************************************************************/
26
27#include <linux/config.h>
28#include <linux/skbuff.h>
29#include <linux/init.h>
30#include <linux/seq_file.h>
31
32#include <asm/byteorder.h>
33#include <asm/unaligned.h>
34
35#include <net/irda/irda.h>
36#include <net/irda/irlap.h>
37#include <net/irda/irlmp.h>
38#include <net/irda/parameters.h>
39#include <net/irda/irttp.h>
40
41static struct irttp_cb *irttp = NULL;
42
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{
89 /* Initialize the irttp structure. */
90 if (irttp == NULL) {
91 irttp = kmalloc(sizeof(struct irttp_cb), GFP_KERNEL);
92 if (irttp == NULL)
93 return -ENOMEM;
94 }
95 memset(irttp, 0, sizeof(struct irttp_cb));
96
97 irttp->magic = TTP_MAGIC;
98
99 irttp->tsaps = hashbin_new(HB_LOCK);
100 if (!irttp->tsaps) {
101 IRDA_ERROR("%s: can't allocate IrTTP hashbin!\n",
102 __FUNCTION__);
103 return -ENOMEM;
104 }
105
106 return 0;
107}
108
109/*
110 * Function irttp_cleanup (void)
111 *
112 * Called by module destruction/cleanup code
113 *
114 */
115void __exit irttp_cleanup(void)
116{
117 /* Check for main structure */
118 IRDA_ASSERT(irttp != NULL, return;);
119 IRDA_ASSERT(irttp->magic == TTP_MAGIC, return;);
120
121 /*
122 * Delete hashbin and close all TSAP instances in it
123 */
124 hashbin_delete(irttp->tsaps, (FREE_FUNC) __irttp_close_tsap);
125
126 irttp->magic = 0;
127
128 /* De-allocate main structure */
129 kfree(irttp);
130
131 irttp = NULL;
132}
133
134/*************************** SUBROUTINES ***************************/
135
136/*
137 * Function irttp_start_todo_timer (self, timeout)
138 *
139 * Start todo timer.
140 *
141 * Made it more effient and unsensitive to race conditions - Jean II
142 */
143static inline void irttp_start_todo_timer(struct tsap_cb *self, int timeout)
144{
145 /* Set new value for timer */
146 mod_timer(&self->todo_timer, jiffies + timeout);
147}
148
149/*
150 * Function irttp_todo_expired (data)
151 *
152 * Todo timer has expired!
153 *
154 * One of the restriction of the timer is that it is run only on the timer
155 * interrupt which run every 10ms. This mean that even if you set the timer
156 * with a delay of 0, it may take up to 10ms before it's run.
157 * So, to minimise latency and keep cache fresh, we try to avoid using
158 * it as much as possible.
159 * Note : we can't use tasklets, because they can't be asynchronously
160 * killed (need user context), and we can't guarantee that here...
161 * Jean II
162 */
163static void irttp_todo_expired(unsigned long data)
164{
165 struct tsap_cb *self = (struct tsap_cb *) data;
166
167 /* Check that we still exist */
168 if (!self || self->magic != TTP_TSAP_MAGIC)
169 return;
170
171 IRDA_DEBUG(4, "%s(instance=%p)\n", __FUNCTION__, self);
172
173 /* Try to make some progress, especially on Tx side - Jean II */
174 irttp_run_rx_queue(self);
175 irttp_run_tx_queue(self);
176
177 /* Check if time for disconnect */
178 if (test_bit(0, &self->disconnect_pend)) {
179 /* Check if it's possible to disconnect yet */
180 if (skb_queue_empty(&self->tx_queue)) {
181 /* Make sure disconnect is not pending anymore */
182 clear_bit(0, &self->disconnect_pend); /* FALSE */
183
184 /* Note : self->disconnect_skb may be NULL */
185 irttp_disconnect_request(self, self->disconnect_skb,
186 P_NORMAL);
187 self->disconnect_skb = NULL;
188 } else {
189 /* Try again later */
190 irttp_start_todo_timer(self, HZ/10);
191
192 /* No reason to try and close now */
193 return;
194 }
195 }
196
197 /* Check if it's closing time */
198 if (self->close_pend)
199 /* Finish cleanup */
200 irttp_close_tsap(self);
201}
202
203/*
204 * Function irttp_flush_queues (self)
205 *
206 * Flushes (removes all frames) in transitt-buffer (tx_list)
207 */
208void irttp_flush_queues(struct tsap_cb *self)
209{
210 struct sk_buff* skb;
211
212 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
213
214 IRDA_ASSERT(self != NULL, return;);
215 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
216
217 /* Deallocate frames waiting to be sent */
218 while ((skb = skb_dequeue(&self->tx_queue)) != NULL)
219 dev_kfree_skb(skb);
220
221 /* Deallocate received frames */
222 while ((skb = skb_dequeue(&self->rx_queue)) != NULL)
223 dev_kfree_skb(skb);
224
225 /* Deallocate received fragments */
226 while ((skb = skb_dequeue(&self->rx_fragments)) != NULL)
227 dev_kfree_skb(skb);
228}
229
230/*
231 * Function irttp_reassemble (self)
232 *
233 * Makes a new (continuous) skb of all the fragments in the fragment
234 * queue
235 *
236 */
237static struct sk_buff *irttp_reassemble_skb(struct tsap_cb *self)
238{
239 struct sk_buff *skb, *frag;
240 int n = 0; /* Fragment index */
241
242 IRDA_ASSERT(self != NULL, return NULL;);
243 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return NULL;);
244
245 IRDA_DEBUG(2, "%s(), self->rx_sdu_size=%d\n", __FUNCTION__,
246 self->rx_sdu_size);
247
248 skb = dev_alloc_skb(TTP_HEADER + self->rx_sdu_size);
249 if (!skb)
250 return NULL;
251
252 /*
253 * Need to reserve space for TTP header in case this skb needs to
254 * be requeued in case delivery failes
255 */
256 skb_reserve(skb, TTP_HEADER);
257 skb_put(skb, self->rx_sdu_size);
258
259 /*
260 * Copy all fragments to a new buffer
261 */
262 while ((frag = skb_dequeue(&self->rx_fragments)) != NULL) {
263 memcpy(skb->data+n, frag->data, frag->len);
264 n += frag->len;
265
266 dev_kfree_skb(frag);
267 }
268
269 IRDA_DEBUG(2,
270 "%s(), frame len=%d, rx_sdu_size=%d, rx_max_sdu_size=%d\n",
271 __FUNCTION__, n, self->rx_sdu_size, self->rx_max_sdu_size);
272 /* Note : irttp_run_rx_queue() calculate self->rx_sdu_size
273 * by summing the size of all fragments, so we should always
274 * have n == self->rx_sdu_size, except in cases where we
275 * droped the last fragment (when self->rx_sdu_size exceed
276 * self->rx_max_sdu_size), where n < self->rx_sdu_size.
277 * Jean II */
278 IRDA_ASSERT(n <= self->rx_sdu_size, n = self->rx_sdu_size;);
279
280 /* Set the new length */
281 skb_trim(skb, n);
282
283 self->rx_sdu_size = 0;
284
285 return skb;
286}
287
288/*
289 * Function irttp_fragment_skb (skb)
290 *
291 * Fragments a frame and queues all the fragments for transmission
292 *
293 */
294static inline void irttp_fragment_skb(struct tsap_cb *self,
295 struct sk_buff *skb)
296{
297 struct sk_buff *frag;
298 __u8 *frame;
299
300 IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
301
302 IRDA_ASSERT(self != NULL, return;);
303 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
304 IRDA_ASSERT(skb != NULL, return;);
305
306 /*
307 * Split frame into a number of segments
308 */
309 while (skb->len > self->max_seg_size) {
310 IRDA_DEBUG(2, "%s(), fragmenting ...\n", __FUNCTION__);
311
312 /* Make new segment */
313 frag = dev_alloc_skb(self->max_seg_size+self->max_header_size);
314 if (!frag)
315 return;
316
317 skb_reserve(frag, self->max_header_size);
318
319 /* Copy data from the original skb into this fragment. */
320 memcpy(skb_put(frag, self->max_seg_size), skb->data,
321 self->max_seg_size);
322
323 /* Insert TTP header, with the more bit set */
324 frame = skb_push(frag, TTP_HEADER);
325 frame[0] = TTP_MORE;
326
327 /* Hide the copied data from the original skb */
328 skb_pull(skb, self->max_seg_size);
329
330 /* Queue fragment */
331 skb_queue_tail(&self->tx_queue, frag);
332 }
333 /* Queue what is left of the original skb */
334 IRDA_DEBUG(2, "%s(), queuing last segment\n", __FUNCTION__);
335
336 frame = skb_push(skb, TTP_HEADER);
337 frame[0] = 0x00; /* Clear more bit */
338
339 /* Queue fragment */
340 skb_queue_tail(&self->tx_queue, skb);
341}
342
343/*
344 * Function irttp_param_max_sdu_size (self, param)
345 *
346 * Handle the MaxSduSize parameter in the connect frames, this function
347 * will be called both when this parameter needs to be inserted into, and
348 * extracted from the connect frames
349 */
350static int irttp_param_max_sdu_size(void *instance, irda_param_t *param,
351 int get)
352{
353 struct tsap_cb *self;
354
355 self = (struct tsap_cb *) instance;
356
357 IRDA_ASSERT(self != NULL, return -1;);
358 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
359
360 if (get)
361 param->pv.i = self->tx_max_sdu_size;
362 else
363 self->tx_max_sdu_size = param->pv.i;
364
365 IRDA_DEBUG(1, "%s(), MaxSduSize=%d\n", __FUNCTION__, param->pv.i);
366
367 return 0;
368}
369
370/*************************** CLIENT CALLS ***************************/
371/************************** LMP CALLBACKS **************************/
372/* Everything is happily mixed up. Waiting for next clean up - Jean II */
373
374/*
375 * Function irttp_open_tsap (stsap, notify)
376 *
377 * Create TSAP connection endpoint,
378 */
379struct tsap_cb *irttp_open_tsap(__u8 stsap_sel, int credit, notify_t *notify)
380{
381 struct tsap_cb *self;
382 struct lsap_cb *lsap;
383 notify_t ttp_notify;
384
385 IRDA_ASSERT(irttp != NULL, return NULL;);
386 IRDA_ASSERT(irttp->magic == TTP_MAGIC, return NULL;);
387
388 /* The IrLMP spec (IrLMP 1.1 p10) says that we have the right to
389 * use only 0x01-0x6F. Of course, we can use LSAP_ANY as well.
390 * JeanII */
391 if((stsap_sel != LSAP_ANY) &&
392 ((stsap_sel < 0x01) || (stsap_sel >= 0x70))) {
393 IRDA_DEBUG(0, "%s(), invalid tsap!\n", __FUNCTION__);
394 return NULL;
395 }
396
397 self = kmalloc(sizeof(struct tsap_cb), GFP_ATOMIC);
398 if (self == NULL) {
399 IRDA_DEBUG(0, "%s(), unable to kmalloc!\n", __FUNCTION__);
400 return NULL;
401 }
402 memset(self, 0, sizeof(struct tsap_cb));
403 spin_lock_init(&self->lock);
404
405 /* Initialise todo timer */
406 init_timer(&self->todo_timer);
407 self->todo_timer.data = (unsigned long) self;
408 self->todo_timer.function = &irttp_todo_expired;
409
410 /* Initialize callbacks for IrLMP to use */
411 irda_notify_init(&ttp_notify);
412 ttp_notify.connect_confirm = irttp_connect_confirm;
413 ttp_notify.connect_indication = irttp_connect_indication;
414 ttp_notify.disconnect_indication = irttp_disconnect_indication;
415 ttp_notify.data_indication = irttp_data_indication;
416 ttp_notify.udata_indication = irttp_udata_indication;
417 ttp_notify.flow_indication = irttp_flow_indication;
418 if(notify->status_indication != NULL)
419 ttp_notify.status_indication = irttp_status_indication;
420 ttp_notify.instance = self;
421 strncpy(ttp_notify.name, notify->name, NOTIFY_MAX_NAME);
422
423 self->magic = TTP_TSAP_MAGIC;
424 self->connected = FALSE;
425
426 skb_queue_head_init(&self->rx_queue);
427 skb_queue_head_init(&self->tx_queue);
428 skb_queue_head_init(&self->rx_fragments);
429 /*
430 * Create LSAP at IrLMP layer
431 */
432 lsap = irlmp_open_lsap(stsap_sel, &ttp_notify, 0);
433 if (lsap == NULL) {
434 IRDA_WARNING("%s: unable to allocate LSAP!!\n", __FUNCTION__);
435 return NULL;
436 }
437
438 /*
439 * If user specified LSAP_ANY as source TSAP selector, then IrLMP
440 * will replace it with whatever source selector which is free, so
441 * the stsap_sel we have might not be valid anymore
442 */
443 self->stsap_sel = lsap->slsap_sel;
444 IRDA_DEBUG(4, "%s(), stsap_sel=%02x\n", __FUNCTION__, self->stsap_sel);
445
446 self->notify = *notify;
447 self->lsap = lsap;
448
449 hashbin_insert(irttp->tsaps, (irda_queue_t *) self, (long) self, NULL);
450
451 if (credit > TTP_RX_MAX_CREDIT)
452 self->initial_credit = TTP_RX_MAX_CREDIT;
453 else
454 self->initial_credit = credit;
455
456 return self;
457}
458EXPORT_SYMBOL(irttp_open_tsap);
459
460/*
461 * Function irttp_close (handle)
462 *
463 * Remove an instance of a TSAP. This function should only deal with the
464 * deallocation of the TSAP, and resetting of the TSAPs values;
465 *
466 */
467static void __irttp_close_tsap(struct tsap_cb *self)
468{
469 /* First make sure we're connected. */
470 IRDA_ASSERT(self != NULL, return;);
471 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
472
473 irttp_flush_queues(self);
474
475 del_timer(&self->todo_timer);
476
477 /* This one won't be cleaned up if we are disconnect_pend + close_pend
478 * and we receive a disconnect_indication */
479 if (self->disconnect_skb)
480 dev_kfree_skb(self->disconnect_skb);
481
482 self->connected = FALSE;
483 self->magic = ~TTP_TSAP_MAGIC;
484
485 kfree(self);
486}
487
488/*
489 * Function irttp_close (self)
490 *
491 * Remove TSAP from list of all TSAPs and then deallocate all resources
492 * associated with this TSAP
493 *
494 * Note : because we *free* the tsap structure, it is the responsibility
495 * of the caller to make sure we are called only once and to deal with
496 * possible race conditions. - Jean II
497 */
498int irttp_close_tsap(struct tsap_cb *self)
499{
500 struct tsap_cb *tsap;
501
502 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
503
504 IRDA_ASSERT(self != NULL, return -1;);
505 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
506
507 /* Make sure tsap has been disconnected */
508 if (self->connected) {
509 /* Check if disconnect is not pending */
510 if (!test_bit(0, &self->disconnect_pend)) {
511 IRDA_WARNING("%s: TSAP still connected!\n",
512 __FUNCTION__);
513 irttp_disconnect_request(self, NULL, P_NORMAL);
514 }
515 self->close_pend = TRUE;
516 irttp_start_todo_timer(self, HZ/10);
517
518 return 0; /* Will be back! */
519 }
520
521 tsap = hashbin_remove(irttp->tsaps, (long) self, NULL);
522
523 IRDA_ASSERT(tsap == self, return -1;);
524
525 /* Close corresponding LSAP */
526 if (self->lsap) {
527 irlmp_close_lsap(self->lsap);
528 self->lsap = NULL;
529 }
530
531 __irttp_close_tsap(self);
532
533 return 0;
534}
535EXPORT_SYMBOL(irttp_close_tsap);
536
537/*
538 * Function irttp_udata_request (self, skb)
539 *
540 * Send unreliable data on this TSAP
541 *
542 */
543int irttp_udata_request(struct tsap_cb *self, struct sk_buff *skb)
544{
545 IRDA_ASSERT(self != NULL, return -1;);
546 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
547 IRDA_ASSERT(skb != NULL, return -1;);
548
549 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
550
551 /* Check that nothing bad happens */
552 if ((skb->len == 0) || (!self->connected)) {
553 IRDA_DEBUG(1, "%s(), No data, or not connected\n",
554 __FUNCTION__);
555 goto err;
556 }
557
558 if (skb->len > self->max_seg_size) {
559 IRDA_DEBUG(1, "%s(), UData is to large for IrLAP!\n",
560 __FUNCTION__);
561 goto err;
562 }
563
564 irlmp_udata_request(self->lsap, skb);
565 self->stats.tx_packets++;
566
567 return 0;
568
569err:
570 dev_kfree_skb(skb);
571 return -1;
572}
573EXPORT_SYMBOL(irttp_udata_request);
574
575
576/*
577 * Function irttp_data_request (handle, skb)
578 *
579 * Queue frame for transmission. If SAR is enabled, fragement the frame
580 * and queue the fragments for transmission
581 */
582int irttp_data_request(struct tsap_cb *self, struct sk_buff *skb)
583{
584 __u8 *frame;
585 int ret;
586
587 IRDA_ASSERT(self != NULL, return -1;);
588 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
589 IRDA_ASSERT(skb != NULL, return -1;);
590
591 IRDA_DEBUG(2, "%s() : queue len = %d\n", __FUNCTION__,
592 skb_queue_len(&self->tx_queue));
593
594 /* Check that nothing bad happens */
595 if ((skb->len == 0) || (!self->connected)) {
596 IRDA_WARNING("%s: No data, or not connected\n", __FUNCTION__);
597 ret = -ENOTCONN;
598 goto err;
599 }
600
601 /*
602 * Check if SAR is disabled, and the frame is larger than what fits
603 * inside an IrLAP frame
604 */
605 if ((self->tx_max_sdu_size == 0) && (skb->len > self->max_seg_size)) {
606 IRDA_ERROR("%s: SAR disabled, and data is to large for IrLAP!\n",
607 __FUNCTION__);
608 ret = -EMSGSIZE;
609 goto err;
610 }
611
612 /*
613 * Check if SAR is enabled, and the frame is larger than the
614 * TxMaxSduSize
615 */
616 if ((self->tx_max_sdu_size != 0) &&
617 (self->tx_max_sdu_size != TTP_SAR_UNBOUND) &&
618 (skb->len > self->tx_max_sdu_size))
619 {
620 IRDA_ERROR("%s: SAR enabled, but data is larger than TxMaxSduSize!\n",
621 __FUNCTION__);
622 ret = -EMSGSIZE;
623 goto err;
624 }
625 /*
626 * Check if transmit queue is full
627 */
628 if (skb_queue_len(&self->tx_queue) >= TTP_TX_MAX_QUEUE) {
629 /*
630 * Give it a chance to empty itself
631 */
632 irttp_run_tx_queue(self);
633
634 /* Drop packet. This error code should trigger the caller
635 * to resend the data in the client code - Jean II */
636 ret = -ENOBUFS;
637 goto err;
638 }
639
640 /* Queue frame, or queue frame segments */
641 if ((self->tx_max_sdu_size == 0) || (skb->len < self->max_seg_size)) {
642 /* Queue frame */
643 IRDA_ASSERT(skb_headroom(skb) >= TTP_HEADER, return -1;);
644 frame = skb_push(skb, TTP_HEADER);
645 frame[0] = 0x00; /* Clear more bit */
646
647 skb_queue_tail(&self->tx_queue, skb);
648 } else {
649 /*
650 * Fragment the frame, this function will also queue the
651 * fragments, we don't care about the fact the transmit
652 * queue may be overfilled by all the segments for a little
653 * while
654 */
655 irttp_fragment_skb(self, skb);
656 }
657
658 /* Check if we can accept more data from client */
659 if ((!self->tx_sdu_busy) &&
660 (skb_queue_len(&self->tx_queue) > TTP_TX_HIGH_THRESHOLD)) {
661 /* Tx queue filling up, so stop client. */
662 if (self->notify.flow_indication) {
663 self->notify.flow_indication(self->notify.instance,
664 self, FLOW_STOP);
665 }
666 /* self->tx_sdu_busy is the state of the client.
667 * Update state after notifying client to avoid
668 * race condition with irttp_flow_indication().
669 * If the queue empty itself after our test but before
670 * we set the flag, we will fix ourselves below in
671 * irttp_run_tx_queue().
672 * Jean II */
673 self->tx_sdu_busy = TRUE;
674 }
675
676 /* Try to make some progress */
677 irttp_run_tx_queue(self);
678
679 return 0;
680
681err:
682 dev_kfree_skb(skb);
683 return ret;
684}
685EXPORT_SYMBOL(irttp_data_request);
686
687/*
688 * Function irttp_run_tx_queue (self)
689 *
690 * Transmit packets queued for transmission (if possible)
691 *
692 */
693static void irttp_run_tx_queue(struct tsap_cb *self)
694{
695 struct sk_buff *skb;
696 unsigned long flags;
697 int n;
698
699 IRDA_DEBUG(2, "%s() : send_credit = %d, queue_len = %d\n",
700 __FUNCTION__,
701 self->send_credit, skb_queue_len(&self->tx_queue));
702
703 /* Get exclusive access to the tx queue, otherwise don't touch it */
704 if (irda_lock(&self->tx_queue_lock) == FALSE)
705 return;
706
707 /* Try to send out frames as long as we have credits
708 * and as long as LAP is not full. If LAP is full, it will
709 * poll us through irttp_flow_indication() - Jean II */
710 while ((self->send_credit > 0) &&
711 (!irlmp_lap_tx_queue_full(self->lsap)) &&
712 (skb = skb_dequeue(&self->tx_queue)))
713 {
714 /*
715 * Since we can transmit and receive frames concurrently,
716 * the code below is a critical region and we must assure that
717 * nobody messes with the credits while we update them.
718 */
719 spin_lock_irqsave(&self->lock, flags);
720
721 n = self->avail_credit;
722 self->avail_credit = 0;
723
724 /* Only room for 127 credits in frame */
725 if (n > 127) {
726 self->avail_credit = n-127;
727 n = 127;
728 }
729 self->remote_credit += n;
730 self->send_credit--;
731
732 spin_unlock_irqrestore(&self->lock, flags);
733
734 /*
735 * More bit must be set by the data_request() or fragment()
736 * functions
737 */
738 skb->data[0] |= (n & 0x7f);
739
740 /* Detach from socket.
741 * The current skb has a reference to the socket that sent
742 * it (skb->sk). When we pass it to IrLMP, the skb will be
743 * stored in in IrLAP (self->wx_list). When we are within
744 * IrLAP, we lose the notion of socket, so we should not
745 * have a reference to a socket. So, we drop it here.
746 *
747 * Why does it matter ?
748 * When the skb is freed (kfree_skb), if it is associated
749 * with a socket, it release buffer space on the socket
750 * (through sock_wfree() and sock_def_write_space()).
751 * If the socket no longer exist, we may crash. Hard.
752 * When we close a socket, we make sure that associated packets
753 * in IrTTP are freed. However, we have no way to cancel
754 * the packet that we have passed to IrLAP. So, if a packet
755 * remains in IrLAP (retry on the link or else) after we
756 * close the socket, we are dead !
757 * Jean II */
758 if (skb->sk != NULL) {
759 /* IrSOCK application, IrOBEX, ... */
760 skb_orphan(skb);
761 }
762 /* IrCOMM over IrTTP, IrLAN, ... */
763
764 /* Pass the skb to IrLMP - done */
765 irlmp_data_request(self->lsap, skb);
766 self->stats.tx_packets++;
767 }
768
769 /* Check if we can accept more frames from client.
770 * We don't want to wait until the todo timer to do that, and we
771 * can't use tasklets (grr...), so we are obliged to give control
772 * to client. That's ok, this test will be true not too often
773 * (max once per LAP window) and we are called from places
774 * where we can spend a bit of time doing stuff. - Jean II */
775 if ((self->tx_sdu_busy) &&
776 (skb_queue_len(&self->tx_queue) < TTP_TX_LOW_THRESHOLD) &&
777 (!self->close_pend))
778 {
779 if (self->notify.flow_indication)
780 self->notify.flow_indication(self->notify.instance,
781 self, FLOW_START);
782
783 /* self->tx_sdu_busy is the state of the client.
784 * We don't really have a race here, but it's always safer
785 * to update our state after the client - Jean II */
786 self->tx_sdu_busy = FALSE;
787 }
788
789 /* Reset lock */
790 self->tx_queue_lock = 0;
791}
792
793/*
794 * Function irttp_give_credit (self)
795 *
796 * Send a dataless flowdata TTP-PDU and give available credit to peer
797 * TSAP
798 */
799static inline void irttp_give_credit(struct tsap_cb *self)
800{
801 struct sk_buff *tx_skb = NULL;
802 unsigned long flags;
803 int n;
804
805 IRDA_ASSERT(self != NULL, return;);
806 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
807
808 IRDA_DEBUG(4, "%s() send=%d,avail=%d,remote=%d\n",
809 __FUNCTION__,
810 self->send_credit, self->avail_credit, self->remote_credit);
811
812 /* Give credit to peer */
813 tx_skb = dev_alloc_skb(64);
814 if (!tx_skb)
815 return;
816
817 /* Reserve space for LMP, and LAP header */
818 skb_reserve(tx_skb, self->max_header_size);
819
820 /*
821 * Since we can transmit and receive frames concurrently,
822 * the code below is a critical region and we must assure that
823 * nobody messes with the credits while we update them.
824 */
825 spin_lock_irqsave(&self->lock, flags);
826
827 n = self->avail_credit;
828 self->avail_credit = 0;
829
830 /* Only space for 127 credits in frame */
831 if (n > 127) {
832 self->avail_credit = n - 127;
833 n = 127;
834 }
835 self->remote_credit += n;
836
837 spin_unlock_irqrestore(&self->lock, flags);
838
839 skb_put(tx_skb, 1);
840 tx_skb->data[0] = (__u8) (n & 0x7f);
841
842 irlmp_data_request(self->lsap, tx_skb);
843 self->stats.tx_packets++;
844}
845
846/*
847 * Function irttp_udata_indication (instance, sap, skb)
848 *
849 * Received some unit-data (unreliable)
850 *
851 */
852static int irttp_udata_indication(void *instance, void *sap,
853 struct sk_buff *skb)
854{
855 struct tsap_cb *self;
856 int err;
857
858 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
859
860 self = (struct tsap_cb *) instance;
861
862 IRDA_ASSERT(self != NULL, return -1;);
863 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
864 IRDA_ASSERT(skb != NULL, return -1;);
865
866 self->stats.rx_packets++;
867
868 /* Just pass data to layer above */
869 if (self->notify.udata_indication) {
870 err = self->notify.udata_indication(self->notify.instance,
871 self,skb);
872 /* Same comment as in irttp_do_data_indication() */
873 if (!err)
874 return 0;
875 }
876 /* Either no handler, or handler returns an error */
877 dev_kfree_skb(skb);
878
879 return 0;
880}
881
882/*
883 * Function irttp_data_indication (instance, sap, skb)
884 *
885 * Receive segment from IrLMP.
886 *
887 */
888static int irttp_data_indication(void *instance, void *sap,
889 struct sk_buff *skb)
890{
891 struct tsap_cb *self;
892 unsigned long flags;
893 int n;
894
895 self = (struct tsap_cb *) instance;
896
897 n = skb->data[0] & 0x7f; /* Extract the credits */
898
899 self->stats.rx_packets++;
900
901 /* Deal with inbound credit
902 * Since we can transmit and receive frames concurrently,
903 * the code below is a critical region and we must assure that
904 * nobody messes with the credits while we update them.
905 */
906 spin_lock_irqsave(&self->lock, flags);
907 self->send_credit += n;
908 if (skb->len > 1)
909 self->remote_credit--;
910 spin_unlock_irqrestore(&self->lock, flags);
911
912 /*
913 * Data or dataless packet? Dataless frames contains only the
914 * TTP_HEADER.
915 */
916 if (skb->len > 1) {
917 /*
918 * We don't remove the TTP header, since we must preserve the
919 * more bit, so the defragment routing knows what to do
920 */
921 skb_queue_tail(&self->rx_queue, skb);
922 } else {
923 /* Dataless flowdata TTP-PDU */
924 dev_kfree_skb(skb);
925 }
926
927
928 /* Push data to the higher layer.
929 * We do it synchronously because running the todo timer for each
930 * receive packet would be too much overhead and latency.
931 * By passing control to the higher layer, we run the risk that
932 * it may take time or grab a lock. Most often, the higher layer
933 * will only put packet in a queue.
934 * Anyway, packets are only dripping through the IrDA, so we can
935 * have time before the next packet.
936 * Further, we are run from NET_BH, so the worse that can happen is
937 * us missing the optimal time to send back the PF bit in LAP.
938 * Jean II */
939 irttp_run_rx_queue(self);
940
941 /* We now give credits to peer in irttp_run_rx_queue().
942 * We need to send credit *NOW*, otherwise we are going
943 * to miss the next Tx window. The todo timer may take
944 * a while before it's run... - Jean II */
945
946 /*
947 * If the peer device has given us some credits and we didn't have
948 * anyone from before, then we need to shedule the tx queue.
949 * We need to do that because our Tx have stopped (so we may not
950 * get any LAP flow indication) and the user may be stopped as
951 * well. - Jean II
952 */
953 if (self->send_credit == n) {
954 /* Restart pushing stuff to LAP */
955 irttp_run_tx_queue(self);
956 /* Note : we don't want to schedule the todo timer
957 * because it has horrible latency. No tasklets
958 * because the tasklet API is broken. - Jean II */
959 }
960
961 return 0;
962}
963
964/*
965 * Function irttp_status_indication (self, reason)
966 *
967 * Status_indication, just pass to the higher layer...
968 *
969 */
970static void irttp_status_indication(void *instance,
971 LINK_STATUS link, LOCK_STATUS lock)
972{
973 struct tsap_cb *self;
974
975 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
976
977 self = (struct tsap_cb *) instance;
978
979 IRDA_ASSERT(self != NULL, return;);
980 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
981
982 /* Check if client has already closed the TSAP and gone away */
983 if (self->close_pend)
984 return;
985
986 /*
987 * Inform service user if he has requested it
988 */
989 if (self->notify.status_indication != NULL)
990 self->notify.status_indication(self->notify.instance,
991 link, lock);
992 else
993 IRDA_DEBUG(2, "%s(), no handler\n", __FUNCTION__);
994}
995
996/*
997 * Function irttp_flow_indication (self, reason)
998 *
999 * Flow_indication : IrLAP tells us to send more data.
1000 *
1001 */
1002static void irttp_flow_indication(void *instance, void *sap, LOCAL_FLOW flow)
1003{
1004 struct tsap_cb *self;
1005
1006 self = (struct tsap_cb *) instance;
1007
1008 IRDA_ASSERT(self != NULL, return;);
1009 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1010
1011 IRDA_DEBUG(4, "%s(instance=%p)\n", __FUNCTION__, self);
1012
1013 /* We are "polled" directly from LAP, and the LAP want to fill
1014 * its Tx window. We want to do our best to send it data, so that
1015 * we maximise the window. On the other hand, we want to limit the
1016 * amount of work here so that LAP doesn't hang forever waiting
1017 * for packets. - Jean II */
1018
1019 /* Try to send some packets. Currently, LAP calls us every time
1020 * there is one free slot, so we will send only one packet.
1021 * This allow the scheduler to do its round robin - Jean II */
1022 irttp_run_tx_queue(self);
1023
1024 /* Note regarding the interraction with higher layer.
1025 * irttp_run_tx_queue() may call the client when its queue
1026 * start to empty, via notify.flow_indication(). Initially.
1027 * I wanted this to happen in a tasklet, to avoid client
1028 * grabbing the CPU, but we can't use tasklets safely. And timer
1029 * is definitely too slow.
1030 * This will happen only once per LAP window, and usually at
1031 * the third packet (unless window is smaller). LAP is still
1032 * doing mtt and sending first packet so it's sort of OK
1033 * to do that. Jean II */
1034
1035 /* If we need to send disconnect. try to do it now */
1036 if(self->disconnect_pend)
1037 irttp_start_todo_timer(self, 0);
1038}
1039
1040/*
1041 * Function irttp_flow_request (self, command)
1042 *
1043 * This function could be used by the upper layers to tell IrTTP to stop
1044 * delivering frames if the receive queues are starting to get full, or
1045 * to tell IrTTP to start delivering frames again.
1046 */
1047void irttp_flow_request(struct tsap_cb *self, LOCAL_FLOW flow)
1048{
1049 IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
1050
1051 IRDA_ASSERT(self != NULL, return;);
1052 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1053
1054 switch (flow) {
1055 case FLOW_STOP:
1056 IRDA_DEBUG(1, "%s(), flow stop\n", __FUNCTION__);
1057 self->rx_sdu_busy = TRUE;
1058 break;
1059 case FLOW_START:
1060 IRDA_DEBUG(1, "%s(), flow start\n", __FUNCTION__);
1061 self->rx_sdu_busy = FALSE;
1062
1063 /* Client say he can accept more data, try to free our
1064 * queues ASAP - Jean II */
1065 irttp_run_rx_queue(self);
1066
1067 break;
1068 default:
1069 IRDA_DEBUG(1, "%s(), Unknown flow command!\n", __FUNCTION__);
1070 }
1071}
1072EXPORT_SYMBOL(irttp_flow_request);
1073
1074/*
1075 * Function irttp_connect_request (self, dtsap_sel, daddr, qos)
1076 *
1077 * Try to connect to remote destination TSAP selector
1078 *
1079 */
1080int irttp_connect_request(struct tsap_cb *self, __u8 dtsap_sel,
1081 __u32 saddr, __u32 daddr,
1082 struct qos_info *qos, __u32 max_sdu_size,
1083 struct sk_buff *userdata)
1084{
1085 struct sk_buff *tx_skb;
1086 __u8 *frame;
1087 __u8 n;
1088
1089 IRDA_DEBUG(4, "%s(), max_sdu_size=%d\n", __FUNCTION__, max_sdu_size);
1090
1091 IRDA_ASSERT(self != NULL, return -EBADR;);
1092 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -EBADR;);
1093
1094 if (self->connected) {
1095 if(userdata)
1096 dev_kfree_skb(userdata);
1097 return -EISCONN;
1098 }
1099
1100 /* Any userdata supplied? */
1101 if (userdata == NULL) {
1102 tx_skb = dev_alloc_skb(64);
1103 if (!tx_skb)
1104 return -ENOMEM;
1105
1106 /* Reserve space for MUX_CONTROL and LAP header */
1107 skb_reserve(tx_skb, TTP_MAX_HEADER);
1108 } else {
1109 tx_skb = userdata;
1110 /*
1111 * Check that the client has reserved enough space for
1112 * headers
1113 */
1114 IRDA_ASSERT(skb_headroom(userdata) >= TTP_MAX_HEADER,
1115 { dev_kfree_skb(userdata); return -1; } );
1116 }
1117
1118 /* Initialize connection parameters */
1119 self->connected = FALSE;
1120 self->avail_credit = 0;
1121 self->rx_max_sdu_size = max_sdu_size;
1122 self->rx_sdu_size = 0;
1123 self->rx_sdu_busy = FALSE;
1124 self->dtsap_sel = dtsap_sel;
1125
1126 n = self->initial_credit;
1127
1128 self->remote_credit = 0;
1129 self->send_credit = 0;
1130
1131 /*
1132 * Give away max 127 credits for now
1133 */
1134 if (n > 127) {
1135 self->avail_credit=n-127;
1136 n = 127;
1137 }
1138
1139 self->remote_credit = n;
1140
1141 /* SAR enabled? */
1142 if (max_sdu_size > 0) {
1143 IRDA_ASSERT(skb_headroom(tx_skb) >= (TTP_MAX_HEADER + TTP_SAR_HEADER),
1144 { dev_kfree_skb(tx_skb); return -1; } );
1145
1146 /* Insert SAR parameters */
1147 frame = skb_push(tx_skb, TTP_HEADER+TTP_SAR_HEADER);
1148
1149 frame[0] = TTP_PARAMETERS | n;
1150 frame[1] = 0x04; /* Length */
1151 frame[2] = 0x01; /* MaxSduSize */
1152 frame[3] = 0x02; /* Value length */
1153
1154 put_unaligned(cpu_to_be16((__u16) max_sdu_size),
1155 (__u16 *)(frame+4));
1156 } else {
1157 /* Insert plain TTP header */
1158 frame = skb_push(tx_skb, TTP_HEADER);
1159
1160 /* Insert initial credit in frame */
1161 frame[0] = n & 0x7f;
1162 }
1163
1164 /* Connect with IrLMP. No QoS parameters for now */
1165 return irlmp_connect_request(self->lsap, dtsap_sel, saddr, daddr, qos,
1166 tx_skb);
1167}
1168EXPORT_SYMBOL(irttp_connect_request);
1169
1170/*
1171 * Function irttp_connect_confirm (handle, qos, skb)
1172 *
1173 * Sevice user confirms TSAP connection with peer.
1174 *
1175 */
1176static void irttp_connect_confirm(void *instance, void *sap,
1177 struct qos_info *qos, __u32 max_seg_size,
1178 __u8 max_header_size, struct sk_buff *skb)
1179{
1180 struct tsap_cb *self;
1181 int parameters;
1182 int ret;
1183 __u8 plen;
1184 __u8 n;
1185
1186 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
1187
1188 self = (struct tsap_cb *) instance;
1189
1190 IRDA_ASSERT(self != NULL, return;);
1191 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1192 IRDA_ASSERT(skb != NULL, return;);
1193
1194 self->max_seg_size = max_seg_size - TTP_HEADER;
1195 self->max_header_size = max_header_size + TTP_HEADER;
1196
1197 /*
1198 * Check if we have got some QoS parameters back! This should be the
1199 * negotiated QoS for the link.
1200 */
1201 if (qos) {
1202 IRDA_DEBUG(4, "IrTTP, Negotiated BAUD_RATE: %02x\n",
1203 qos->baud_rate.bits);
1204 IRDA_DEBUG(4, "IrTTP, Negotiated BAUD_RATE: %d bps.\n",
1205 qos->baud_rate.value);
1206 }
1207
1208 n = skb->data[0] & 0x7f;
1209
1210 IRDA_DEBUG(4, "%s(), Initial send_credit=%d\n", __FUNCTION__, n);
1211
1212 self->send_credit = n;
1213 self->tx_max_sdu_size = 0;
1214 self->connected = TRUE;
1215
1216 parameters = skb->data[0] & 0x80;
1217
1218 IRDA_ASSERT(skb->len >= TTP_HEADER, return;);
1219 skb_pull(skb, TTP_HEADER);
1220
1221 if (parameters) {
1222 plen = skb->data[0];
1223
1224 ret = irda_param_extract_all(self, skb->data+1,
1225 IRDA_MIN(skb->len-1, plen),
1226 &param_info);
1227
1228 /* Any errors in the parameter list? */
1229 if (ret < 0) {
1230 IRDA_WARNING("%s: error extracting parameters\n",
1231 __FUNCTION__);
1232 dev_kfree_skb(skb);
1233
1234 /* Do not accept this connection attempt */
1235 return;
1236 }
1237 /* Remove parameters */
1238 skb_pull(skb, IRDA_MIN(skb->len, plen+1));
1239 }
1240
1241 IRDA_DEBUG(4, "%s() send=%d,avail=%d,remote=%d\n", __FUNCTION__,
1242 self->send_credit, self->avail_credit, self->remote_credit);
1243
1244 IRDA_DEBUG(2, "%s(), MaxSduSize=%d\n", __FUNCTION__,
1245 self->tx_max_sdu_size);
1246
1247 if (self->notify.connect_confirm) {
1248 self->notify.connect_confirm(self->notify.instance, self, qos,
1249 self->tx_max_sdu_size,
1250 self->max_header_size, skb);
1251 } else
1252 dev_kfree_skb(skb);
1253}
1254
1255/*
1256 * Function irttp_connect_indication (handle, skb)
1257 *
1258 * Some other device is connecting to this TSAP
1259 *
1260 */
1261void irttp_connect_indication(void *instance, void *sap, struct qos_info *qos,
1262 __u32 max_seg_size, __u8 max_header_size,
1263 struct sk_buff *skb)
1264{
1265 struct tsap_cb *self;
1266 struct lsap_cb *lsap;
1267 int parameters;
1268 int ret;
1269 __u8 plen;
1270 __u8 n;
1271
1272 self = (struct tsap_cb *) instance;
1273
1274 IRDA_ASSERT(self != NULL, return;);
1275 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1276 IRDA_ASSERT(skb != NULL, return;);
1277
1278 lsap = (struct lsap_cb *) sap;
1279
1280 self->max_seg_size = max_seg_size - TTP_HEADER;
1281 self->max_header_size = max_header_size+TTP_HEADER;
1282
1283 IRDA_DEBUG(4, "%s(), TSAP sel=%02x\n", __FUNCTION__, self->stsap_sel);
1284
1285 /* Need to update dtsap_sel if its equal to LSAP_ANY */
1286 self->dtsap_sel = lsap->dlsap_sel;
1287
1288 n = skb->data[0] & 0x7f;
1289
1290 self->send_credit = n;
1291 self->tx_max_sdu_size = 0;
1292
1293 parameters = skb->data[0] & 0x80;
1294
1295 IRDA_ASSERT(skb->len >= TTP_HEADER, return;);
1296 skb_pull(skb, TTP_HEADER);
1297
1298 if (parameters) {
1299 plen = skb->data[0];
1300
1301 ret = irda_param_extract_all(self, skb->data+1,
1302 IRDA_MIN(skb->len-1, plen),
1303 &param_info);
1304
1305 /* Any errors in the parameter list? */
1306 if (ret < 0) {
1307 IRDA_WARNING("%s: error extracting parameters\n",
1308 __FUNCTION__);
1309 dev_kfree_skb(skb);
1310
1311 /* Do not accept this connection attempt */
1312 return;
1313 }
1314
1315 /* Remove parameters */
1316 skb_pull(skb, IRDA_MIN(skb->len, plen+1));
1317 }
1318
1319 if (self->notify.connect_indication) {
1320 self->notify.connect_indication(self->notify.instance, self,
1321 qos, self->tx_max_sdu_size,
1322 self->max_header_size, skb);
1323 } else
1324 dev_kfree_skb(skb);
1325}
1326
1327/*
1328 * Function irttp_connect_response (handle, userdata)
1329 *
1330 * Service user is accepting the connection, just pass it down to
1331 * IrLMP!
1332 *
1333 */
1334int irttp_connect_response(struct tsap_cb *self, __u32 max_sdu_size,
1335 struct sk_buff *userdata)
1336{
1337 struct sk_buff *tx_skb;
1338 __u8 *frame;
1339 int ret;
1340 __u8 n;
1341
1342 IRDA_ASSERT(self != NULL, return -1;);
1343 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
1344
1345 IRDA_DEBUG(4, "%s(), Source TSAP selector=%02x\n", __FUNCTION__,
1346 self->stsap_sel);
1347
1348 /* Any userdata supplied? */
1349 if (userdata == NULL) {
1350 tx_skb = dev_alloc_skb(64);
1351 if (!tx_skb)
1352 return -ENOMEM;
1353
1354 /* Reserve space for MUX_CONTROL and LAP header */
1355 skb_reserve(tx_skb, TTP_MAX_HEADER);
1356 } else {
1357 tx_skb = userdata;
1358 /*
1359 * Check that the client has reserved enough space for
1360 * headers
1361 */
1362 IRDA_ASSERT(skb_headroom(userdata) >= TTP_MAX_HEADER,
1363 { dev_kfree_skb(userdata); return -1; } );
1364 }
1365
1366 self->avail_credit = 0;
1367 self->remote_credit = 0;
1368 self->rx_max_sdu_size = max_sdu_size;
1369 self->rx_sdu_size = 0;
1370 self->rx_sdu_busy = FALSE;
1371
1372 n = self->initial_credit;
1373
1374 /* Frame has only space for max 127 credits (7 bits) */
1375 if (n > 127) {
1376 self->avail_credit = n - 127;
1377 n = 127;
1378 }
1379
1380 self->remote_credit = n;
1381 self->connected = TRUE;
1382
1383 /* SAR enabled? */
1384 if (max_sdu_size > 0) {
1385 IRDA_ASSERT(skb_headroom(tx_skb) >= (TTP_MAX_HEADER + TTP_SAR_HEADER),
1386 { dev_kfree_skb(tx_skb); return -1; } );
1387
1388 /* Insert TTP header with SAR parameters */
1389 frame = skb_push(tx_skb, TTP_HEADER+TTP_SAR_HEADER);
1390
1391 frame[0] = TTP_PARAMETERS | n;
1392 frame[1] = 0x04; /* Length */
1393
1394 /* irda_param_insert(self, IRTTP_MAX_SDU_SIZE, frame+1, */
1395/* TTP_SAR_HEADER, &param_info) */
1396
1397 frame[2] = 0x01; /* MaxSduSize */
1398 frame[3] = 0x02; /* Value length */
1399
1400 put_unaligned(cpu_to_be16((__u16) max_sdu_size),
1401 (__u16 *)(frame+4));
1402 } else {
1403 /* Insert TTP header */
1404 frame = skb_push(tx_skb, TTP_HEADER);
1405
1406 frame[0] = n & 0x7f;
1407 }
1408
1409 ret = irlmp_connect_response(self->lsap, tx_skb);
1410
1411 return ret;
1412}
1413EXPORT_SYMBOL(irttp_connect_response);
1414
1415/*
1416 * Function irttp_dup (self, instance)
1417 *
1418 * Duplicate TSAP, can be used by servers to confirm a connection on a
1419 * new TSAP so it can keep listening on the old one.
1420 */
1421struct tsap_cb *irttp_dup(struct tsap_cb *orig, void *instance)
1422{
1423 struct tsap_cb *new;
1424 unsigned long flags;
1425
1426 IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
1427
1428 /* Protect our access to the old tsap instance */
1429 spin_lock_irqsave(&irttp->tsaps->hb_spinlock, flags);
1430
1431 /* Find the old instance */
1432 if (!hashbin_find(irttp->tsaps, (long) orig, NULL)) {
1433 IRDA_DEBUG(0, "%s(), unable to find TSAP\n", __FUNCTION__);
1434 spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
1435 return NULL;
1436 }
1437
1438 /* Allocate a new instance */
1439 new = kmalloc(sizeof(struct tsap_cb), GFP_ATOMIC);
1440 if (!new) {
1441 IRDA_DEBUG(0, "%s(), unable to kmalloc\n", __FUNCTION__);
1442 spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
1443 return NULL;
1444 }
1445 /* Dup */
1446 memcpy(new, orig, sizeof(struct tsap_cb));
1447
1448 /* We don't need the old instance any more */
1449 spin_unlock_irqrestore(&irttp->tsaps->hb_spinlock, flags);
1450
1451 /* Try to dup the LSAP (may fail if we were too slow) */
1452 new->lsap = irlmp_dup(orig->lsap, new);
1453 if (!new->lsap) {
1454 IRDA_DEBUG(0, "%s(), dup failed!\n", __FUNCTION__);
1455 kfree(new);
1456 return NULL;
1457 }
1458
1459 /* Not everything should be copied */
1460 new->notify.instance = instance;
1461 init_timer(&new->todo_timer);
1462
1463 skb_queue_head_init(&new->rx_queue);
1464 skb_queue_head_init(&new->tx_queue);
1465 skb_queue_head_init(&new->rx_fragments);
1466
1467 /* This is locked */
1468 hashbin_insert(irttp->tsaps, (irda_queue_t *) new, (long) new, NULL);
1469
1470 return new;
1471}
1472EXPORT_SYMBOL(irttp_dup);
1473
1474/*
1475 * Function irttp_disconnect_request (self)
1476 *
1477 * Close this connection please! If priority is high, the queued data
1478 * segments, if any, will be deallocated first
1479 *
1480 */
1481int irttp_disconnect_request(struct tsap_cb *self, struct sk_buff *userdata,
1482 int priority)
1483{
1484 int ret;
1485
1486 IRDA_ASSERT(self != NULL, return -1;);
1487 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return -1;);
1488
1489 /* Already disconnected? */
1490 if (!self->connected) {
1491 IRDA_DEBUG(4, "%s(), already disconnected!\n", __FUNCTION__);
1492 if (userdata)
1493 dev_kfree_skb(userdata);
1494 return -1;
1495 }
1496
1497 /* Disconnect already pending ?
1498 * We need to use an atomic operation to prevent reentry. This
1499 * function may be called from various context, like user, timer
1500 * for following a disconnect_indication() (i.e. net_bh).
1501 * Jean II */
1502 if(test_and_set_bit(0, &self->disconnect_pend)) {
1503 IRDA_DEBUG(0, "%s(), disconnect already pending\n",
1504 __FUNCTION__);
1505 if (userdata)
1506 dev_kfree_skb(userdata);
1507
1508 /* Try to make some progress */
1509 irttp_run_tx_queue(self);
1510 return -1;
1511 }
1512
1513 /*
1514 * Check if there is still data segments in the transmit queue
1515 */
1516 if (skb_queue_len(&self->tx_queue) > 0) {
1517 if (priority == P_HIGH) {
1518 /*
1519 * No need to send the queued data, if we are
1520 * disconnecting right now since the data will
1521 * not have any usable connection to be sent on
1522 */
1523 IRDA_DEBUG(1, "%s(): High priority!!()\n", __FUNCTION__);
1524 irttp_flush_queues(self);
1525 } else if (priority == P_NORMAL) {
1526 /*
1527 * Must delay disconnect until after all data segments
1528 * have been sent and the tx_queue is empty
1529 */
1530 /* We'll reuse this one later for the disconnect */
1531 self->disconnect_skb = userdata; /* May be NULL */
1532
1533 irttp_run_tx_queue(self);
1534
1535 irttp_start_todo_timer(self, HZ/10);
1536 return -1;
1537 }
1538 }
1539 /* Note : we don't need to check if self->rx_queue is full and the
1540 * state of self->rx_sdu_busy because the disconnect response will
1541 * be sent at the LMP level (so even if the peer has its Tx queue
1542 * full of data). - Jean II */
1543
1544 IRDA_DEBUG(1, "%s(), Disconnecting ...\n", __FUNCTION__);
1545 self->connected = FALSE;
1546
1547 if (!userdata) {
1548 struct sk_buff *tx_skb;
1549 tx_skb = dev_alloc_skb(64);
1550 if (!tx_skb)
1551 return -ENOMEM;
1552
1553 /*
1554 * Reserve space for MUX and LAP header
1555 */
1556 skb_reserve(tx_skb, TTP_MAX_HEADER);
1557
1558 userdata = tx_skb;
1559 }
1560 ret = irlmp_disconnect_request(self->lsap, userdata);
1561
1562 /* The disconnect is no longer pending */
1563 clear_bit(0, &self->disconnect_pend); /* FALSE */
1564
1565 return ret;
1566}
1567EXPORT_SYMBOL(irttp_disconnect_request);
1568
1569/*
1570 * Function irttp_disconnect_indication (self, reason)
1571 *
1572 * Disconnect indication, TSAP disconnected by peer?
1573 *
1574 */
1575void irttp_disconnect_indication(void *instance, void *sap, LM_REASON reason,
1576 struct sk_buff *skb)
1577{
1578 struct tsap_cb *self;
1579
1580 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
1581
1582 self = (struct tsap_cb *) instance;
1583
1584 IRDA_ASSERT(self != NULL, return;);
1585 IRDA_ASSERT(self->magic == TTP_TSAP_MAGIC, return;);
1586
1587 /* Prevent higher layer to send more data */
1588 self->connected = FALSE;
1589
1590 /* Check if client has already tried to close the TSAP */
1591 if (self->close_pend) {
1592 /* In this case, the higher layer is probably gone. Don't
1593 * bother it and clean up the remains - Jean II */
1594 if (skb)
1595 dev_kfree_skb(skb);
1596 irttp_close_tsap(self);
1597 return;
1598 }
1599
1600 /* If we are here, we assume that is the higher layer is still
1601 * waiting for the disconnect notification and able to process it,
1602 * even if he tried to disconnect. Otherwise, it would have already
1603 * attempted to close the tsap and self->close_pend would be TRUE.
1604 * Jean II */
1605
1606 /* No need to notify the client if has already tried to disconnect */
1607 if(self->notify.disconnect_indication)
1608 self->notify.disconnect_indication(self->notify.instance, self,
1609 reason, skb);
1610 else
1611 if (skb)
1612 dev_kfree_skb(skb);
1613}
1614
1615/*
1616 * Function irttp_do_data_indication (self, skb)
1617 *
1618 * Try to deliver reassembled skb to layer above, and requeue it if that
1619 * for some reason should fail. We mark rx sdu as busy to apply back
1620 * pressure is necessary.
1621 */
1622static void irttp_do_data_indication(struct tsap_cb *self, struct sk_buff *skb)
1623{
1624 int err;
1625
1626 /* Check if client has already closed the TSAP and gone away */
1627 if (self->close_pend) {
1628 dev_kfree_skb(skb);
1629 return;
1630 }
1631
1632 err = self->notify.data_indication(self->notify.instance, self, skb);
1633
1634 /* Usually the layer above will notify that it's input queue is
1635 * starting to get filled by using the flow request, but this may
1636 * be difficult, so it can instead just refuse to eat it and just
1637 * give an error back
1638 */
1639 if (err) {
1640 IRDA_DEBUG(0, "%s() requeueing skb!\n", __FUNCTION__);
1641
1642 /* Make sure we take a break */
1643 self->rx_sdu_busy = TRUE;
1644
1645 /* Need to push the header in again */
1646 skb_push(skb, TTP_HEADER);
1647 skb->data[0] = 0x00; /* Make sure MORE bit is cleared */
1648
1649 /* Put skb back on queue */
1650 skb_queue_head(&self->rx_queue, skb);
1651 }
1652}
1653
1654/*
1655 * Function irttp_run_rx_queue (self)
1656 *
1657 * Check if we have any frames to be transmitted, or if we have any
1658 * available credit to give away.
1659 */
1660void irttp_run_rx_queue(struct tsap_cb *self)
1661{
1662 struct sk_buff *skb;
1663 int more = 0;
1664
1665 IRDA_DEBUG(2, "%s() send=%d,avail=%d,remote=%d\n", __FUNCTION__,
1666 self->send_credit, self->avail_credit, self->remote_credit);
1667
1668 /* Get exclusive access to the rx queue, otherwise don't touch it */
1669 if (irda_lock(&self->rx_queue_lock) == FALSE)
1670 return;
1671
1672 /*
1673 * Reassemble all frames in receive queue and deliver them
1674 */
1675 while (!self->rx_sdu_busy && (skb = skb_dequeue(&self->rx_queue))) {
1676 /* This bit will tell us if it's the last fragment or not */
1677 more = skb->data[0] & 0x80;
1678
1679 /* Remove TTP header */
1680 skb_pull(skb, TTP_HEADER);
1681
1682 /* Add the length of the remaining data */
1683 self->rx_sdu_size += skb->len;
1684
1685 /*
1686 * If SAR is disabled, or user has requested no reassembly
1687 * of received fragments then we just deliver them
1688 * immediately. This can be requested by clients that
1689 * implements byte streams without any message boundaries
1690 */
1691 if (self->rx_max_sdu_size == TTP_SAR_DISABLE) {
1692 irttp_do_data_indication(self, skb);
1693 self->rx_sdu_size = 0;
1694
1695 continue;
1696 }
1697
1698 /* Check if this is a fragment, and not the last fragment */
1699 if (more) {
1700 /*
1701 * Queue the fragment if we still are within the
1702 * limits of the maximum size of the rx_sdu
1703 */
1704 if (self->rx_sdu_size <= self->rx_max_sdu_size) {
1705 IRDA_DEBUG(4, "%s(), queueing frag\n",
1706 __FUNCTION__);
1707 skb_queue_tail(&self->rx_fragments, skb);
1708 } else {
1709 /* Free the part of the SDU that is too big */
1710 dev_kfree_skb(skb);
1711 }
1712 continue;
1713 }
1714 /*
1715 * This is the last fragment, so time to reassemble!
1716 */
1717 if ((self->rx_sdu_size <= self->rx_max_sdu_size) ||
1718 (self->rx_max_sdu_size == TTP_SAR_UNBOUND))
1719 {
1720 /*
1721 * A little optimizing. Only queue the fragment if
1722 * there are other fragments. Since if this is the
1723 * last and only fragment, there is no need to
1724 * reassemble :-)
1725 */
1726 if (!skb_queue_empty(&self->rx_fragments)) {
1727 skb_queue_tail(&self->rx_fragments,
1728 skb);
1729
1730 skb = irttp_reassemble_skb(self);
1731 }
1732
1733 /* Now we can deliver the reassembled skb */
1734 irttp_do_data_indication(self, skb);
1735 } else {
1736 IRDA_DEBUG(1, "%s(), Truncated frame\n", __FUNCTION__);
1737
1738 /* Free the part of the SDU that is too big */
1739 dev_kfree_skb(skb);
1740
1741 /* Deliver only the valid but truncated part of SDU */
1742 skb = irttp_reassemble_skb(self);
1743
1744 irttp_do_data_indication(self, skb);
1745 }
1746 self->rx_sdu_size = 0;
1747 }
1748
1749 /*
1750 * It's not trivial to keep track of how many credits are available
1751 * by incrementing at each packet, because delivery may fail
1752 * (irttp_do_data_indication() may requeue the frame) and because
1753 * we need to take care of fragmentation.
1754 * We want the other side to send up to initial_credit packets.
1755 * We have some frames in our queues, and we have already allowed it
1756 * to send remote_credit.
1757 * No need to spinlock, write is atomic and self correcting...
1758 * Jean II
1759 */
1760 self->avail_credit = (self->initial_credit -
1761 (self->remote_credit +
1762 skb_queue_len(&self->rx_queue) +
1763 skb_queue_len(&self->rx_fragments)));
1764
1765 /* Do we have too much credits to send to peer ? */
1766 if ((self->remote_credit <= TTP_RX_MIN_CREDIT) &&
1767 (self->avail_credit > 0)) {
1768 /* Send explicit credit frame */
1769 irttp_give_credit(self);
1770 /* Note : do *NOT* check if tx_queue is non-empty, that
1771 * will produce deadlocks. I repeat : send a credit frame
1772 * even if we have something to send in our Tx queue.
1773 * If we have credits, it means that our Tx queue is blocked.
1774 *
1775 * Let's suppose the peer can't keep up with our Tx. He will
1776 * flow control us by not sending us any credits, and we
1777 * will stop Tx and start accumulating credits here.
1778 * Up to the point where the peer will stop its Tx queue,
1779 * for lack of credits.
1780 * Let's assume the peer application is single threaded.
1781 * It will block on Tx and never consume any Rx buffer.
1782 * Deadlock. Guaranteed. - Jean II
1783 */
1784 }
1785
1786 /* Reset lock */
1787 self->rx_queue_lock = 0;
1788}
1789
1790#ifdef CONFIG_PROC_FS
1791struct irttp_iter_state {
1792 int id;
1793};
1794
1795static void *irttp_seq_start(struct seq_file *seq, loff_t *pos)
1796{
1797 struct irttp_iter_state *iter = seq->private;
1798 struct tsap_cb *self;
1799
1800 /* Protect our access to the tsap list */
1801 spin_lock_irq(&irttp->tsaps->hb_spinlock);
1802 iter->id = 0;
1803
1804 for (self = (struct tsap_cb *) hashbin_get_first(irttp->tsaps);
1805 self != NULL;
1806 self = (struct tsap_cb *) hashbin_get_next(irttp->tsaps)) {
1807 if (iter->id == *pos)
1808 break;
1809 ++iter->id;
1810 }
1811
1812 return self;
1813}
1814
1815static void *irttp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1816{
1817 struct irttp_iter_state *iter = seq->private;
1818
1819 ++*pos;
1820 ++iter->id;
1821 return (void *) hashbin_get_next(irttp->tsaps);
1822}
1823
1824static void irttp_seq_stop(struct seq_file *seq, void *v)
1825{
1826 spin_unlock_irq(&irttp->tsaps->hb_spinlock);
1827}
1828
1829static int irttp_seq_show(struct seq_file *seq, void *v)
1830{
1831 const struct irttp_iter_state *iter = seq->private;
1832 const struct tsap_cb *self = v;
1833
1834 seq_printf(seq, "TSAP %d, ", iter->id);
1835 seq_printf(seq, "stsap_sel: %02x, ",
1836 self->stsap_sel);
1837 seq_printf(seq, "dtsap_sel: %02x\n",
1838 self->dtsap_sel);
1839 seq_printf(seq, " connected: %s, ",
1840 self->connected? "TRUE":"FALSE");
1841 seq_printf(seq, "avail credit: %d, ",
1842 self->avail_credit);
1843 seq_printf(seq, "remote credit: %d, ",
1844 self->remote_credit);
1845 seq_printf(seq, "send credit: %d\n",
1846 self->send_credit);
1847 seq_printf(seq, " tx packets: %ld, ",
1848 self->stats.tx_packets);
1849 seq_printf(seq, "rx packets: %ld, ",
1850 self->stats.rx_packets);
1851 seq_printf(seq, "tx_queue len: %d ",
1852 skb_queue_len(&self->tx_queue));
1853 seq_printf(seq, "rx_queue len: %d\n",
1854 skb_queue_len(&self->rx_queue));
1855 seq_printf(seq, " tx_sdu_busy: %s, ",
1856 self->tx_sdu_busy? "TRUE":"FALSE");
1857 seq_printf(seq, "rx_sdu_busy: %s\n",
1858 self->rx_sdu_busy? "TRUE":"FALSE");
1859 seq_printf(seq, " max_seg_size: %d, ",
1860 self->max_seg_size);
1861 seq_printf(seq, "tx_max_sdu_size: %d, ",
1862 self->tx_max_sdu_size);
1863 seq_printf(seq, "rx_max_sdu_size: %d\n",
1864 self->rx_max_sdu_size);
1865
1866 seq_printf(seq, " Used by (%s)\n\n",
1867 self->notify.name);
1868 return 0;
1869}
1870
1871static struct seq_operations irttp_seq_ops = {
1872 .start = irttp_seq_start,
1873 .next = irttp_seq_next,
1874 .stop = irttp_seq_stop,
1875 .show = irttp_seq_show,
1876};
1877
1878static int irttp_seq_open(struct inode *inode, struct file *file)
1879{
1880 struct seq_file *seq;
1881 int rc = -ENOMEM;
1882 struct irttp_iter_state *s;
1883
1884 IRDA_ASSERT(irttp != NULL, return -EINVAL;);
1885
1886 s = kmalloc(sizeof(*s), GFP_KERNEL);
1887 if (!s)
1888 goto out;
1889
1890 rc = seq_open(file, &irttp_seq_ops);
1891 if (rc)
1892 goto out_kfree;
1893
1894 seq = file->private_data;
1895 seq->private = s;
1896 memset(s, 0, sizeof(*s));
1897out:
1898 return rc;
1899out_kfree:
1900 kfree(s);
1901 goto out;
1902}
1903
1904struct file_operations irttp_seq_fops = {
1905 .owner = THIS_MODULE,
1906 .open = irttp_seq_open,
1907 .read = seq_read,
1908 .llseek = seq_lseek,
1909 .release = seq_release_private,
1910};
1911
1912#endif /* PROC_FS */
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-19 03:21:23 -0500