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v3.1
  1/*********************************************************************
  2 *
  3 * Filename:      irlmp_frame.c
  4 * Version:       0.9
  5 * Description:   IrLMP frame implementation
  6 * Status:        Experimental.
  7 * Author:        Dag Brattli <dagb@cs.uit.no>
  8 * Created at:    Tue Aug 19 02:09:59 1997
  9 * Modified at:   Mon Dec 13 13:41:12 1999
 10 * Modified by:   Dag Brattli <dagb@cs.uit.no>
 11 *
 12 *     Copyright (c) 1998-1999 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
 27#include <linux/skbuff.h>
 28#include <linux/kernel.h>
 29
 30#include <net/irda/irda.h>
 31#include <net/irda/irlap.h>
 32#include <net/irda/timer.h>
 33#include <net/irda/irlmp.h>
 34#include <net/irda/irlmp_frame.h>
 35#include <net/irda/discovery.h>
 36
 37static struct lsap_cb *irlmp_find_lsap(struct lap_cb *self, __u8 dlsap,
 38				       __u8 slsap, int status, hashbin_t *);
 39
 40inline void irlmp_send_data_pdu(struct lap_cb *self, __u8 dlsap, __u8 slsap,
 41				int expedited, struct sk_buff *skb)
 42{
 43	skb->data[0] = dlsap;
 44	skb->data[1] = slsap;
 45
 46	if (expedited) {
 47		IRDA_DEBUG(4, "%s(), sending expedited data\n", __func__);
 48		irlap_data_request(self->irlap, skb, TRUE);
 49	} else
 50		irlap_data_request(self->irlap, skb, FALSE);
 51}
 52
 53/*
 54 * Function irlmp_send_lcf_pdu (dlsap, slsap, opcode,skb)
 55 *
 56 *    Send Link Control Frame to IrLAP
 57 */
 58void irlmp_send_lcf_pdu(struct lap_cb *self, __u8 dlsap, __u8 slsap,
 59			__u8 opcode, struct sk_buff *skb)
 60{
 61	__u8 *frame;
 62
 63	IRDA_DEBUG(2, "%s()\n", __func__);
 64
 65	IRDA_ASSERT(self != NULL, return;);
 66	IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
 67	IRDA_ASSERT(skb != NULL, return;);
 68
 69	frame = skb->data;
 70
 71	frame[0] = dlsap | CONTROL_BIT;
 72	frame[1] = slsap;
 73
 74	frame[2] = opcode;
 75
 76	if (opcode == DISCONNECT)
 77		frame[3] = 0x01; /* Service user request */
 78	else
 79		frame[3] = 0x00; /* rsvd */
 80
 81	irlap_data_request(self->irlap, skb, FALSE);
 82}
 83
 84/*
 85 * Function irlmp_input (skb)
 86 *
 87 *    Used by IrLAP to pass received data frames to IrLMP layer
 88 *
 89 */
 90void irlmp_link_data_indication(struct lap_cb *self, struct sk_buff *skb,
 91				int unreliable)
 92{
 93	struct lsap_cb *lsap;
 94	__u8   slsap_sel;   /* Source (this) LSAP address */
 95	__u8   dlsap_sel;   /* Destination LSAP address */
 96	__u8   *fp;
 97
 98	IRDA_DEBUG(4, "%s()\n", __func__);
 99
100	IRDA_ASSERT(self != NULL, return;);
101	IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
102	IRDA_ASSERT(skb->len > 2, return;);
103
104	fp = skb->data;
105
106	/*
107	 *  The next statements may be confusing, but we do this so that
108	 *  destination LSAP of received frame is source LSAP in our view
109	 */
110	slsap_sel = fp[0] & LSAP_MASK;
111	dlsap_sel = fp[1];
112
113	/*
114	 *  Check if this is an incoming connection, since we must deal with
115	 *  it in a different way than other established connections.
116	 */
117	if ((fp[0] & CONTROL_BIT) && (fp[2] == CONNECT_CMD)) {
118		IRDA_DEBUG(3, "%s(), incoming connection, "
119			   "source LSAP=%d, dest LSAP=%d\n",
120			   __func__, slsap_sel, dlsap_sel);
121
122		/* Try to find LSAP among the unconnected LSAPs */
123		lsap = irlmp_find_lsap(self, dlsap_sel, slsap_sel, CONNECT_CMD,
124				       irlmp->unconnected_lsaps);
125
126		/* Maybe LSAP was already connected, so try one more time */
127		if (!lsap) {
128			IRDA_DEBUG(1, "%s(), incoming connection for LSAP already connected\n", __func__);
129			lsap = irlmp_find_lsap(self, dlsap_sel, slsap_sel, 0,
130					       self->lsaps);
131		}
132	} else
133		lsap = irlmp_find_lsap(self, dlsap_sel, slsap_sel, 0,
134				       self->lsaps);
135
136	if (lsap == NULL) {
137		IRDA_DEBUG(2, "IrLMP, Sorry, no LSAP for received frame!\n");
138		IRDA_DEBUG(2, "%s(), slsap_sel = %02x, dlsap_sel = %02x\n",
139			   __func__, slsap_sel, dlsap_sel);
140		if (fp[0] & CONTROL_BIT) {
141			IRDA_DEBUG(2, "%s(), received control frame %02x\n",
142				   __func__, fp[2]);
143		} else {
144			IRDA_DEBUG(2, "%s(), received data frame\n", __func__);
145		}
146		return;
147	}
148
149	/*
150	 *  Check if we received a control frame?
151	 */
152	if (fp[0] & CONTROL_BIT) {
153		switch (fp[2]) {
154		case CONNECT_CMD:
155			lsap->lap = self;
156			irlmp_do_lsap_event(lsap, LM_CONNECT_INDICATION, skb);
157			break;
158		case CONNECT_CNF:
159			irlmp_do_lsap_event(lsap, LM_CONNECT_CONFIRM, skb);
160			break;
161		case DISCONNECT:
162			IRDA_DEBUG(4, "%s(), Disconnect indication!\n",
163				   __func__);
164			irlmp_do_lsap_event(lsap, LM_DISCONNECT_INDICATION,
165					    skb);
166			break;
167		case ACCESSMODE_CMD:
168			IRDA_DEBUG(0, "Access mode cmd not implemented!\n");
169			break;
170		case ACCESSMODE_CNF:
171			IRDA_DEBUG(0, "Access mode cnf not implemented!\n");
172			break;
173		default:
174			IRDA_DEBUG(0, "%s(), Unknown control frame %02x\n",
175				   __func__, fp[2]);
176			break;
177		}
178	} else if (unreliable) {
179		/* Optimize and bypass the state machine if possible */
180		if (lsap->lsap_state == LSAP_DATA_TRANSFER_READY)
181			irlmp_udata_indication(lsap, skb);
182		else
183			irlmp_do_lsap_event(lsap, LM_UDATA_INDICATION, skb);
184	} else {
185		/* Optimize and bypass the state machine if possible */
186		if (lsap->lsap_state == LSAP_DATA_TRANSFER_READY)
187			irlmp_data_indication(lsap, skb);
188		else
189			irlmp_do_lsap_event(lsap, LM_DATA_INDICATION, skb);
190	}
191}
192
193/*
194 * Function irlmp_link_unitdata_indication (self, skb)
195 *
196 *
197 *
198 */
199#ifdef CONFIG_IRDA_ULTRA
200void irlmp_link_unitdata_indication(struct lap_cb *self, struct sk_buff *skb)
201{
202	struct lsap_cb *lsap;
203	__u8   slsap_sel;   /* Source (this) LSAP address */
204	__u8   dlsap_sel;   /* Destination LSAP address */
205	__u8   pid;         /* Protocol identifier */
206	__u8   *fp;
207	unsigned long flags;
208
209	IRDA_DEBUG(4, "%s()\n", __func__);
210
211	IRDA_ASSERT(self != NULL, return;);
212	IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
213	IRDA_ASSERT(skb->len > 2, return;);
214
215	fp = skb->data;
216
217	/*
218	 *  The next statements may be confusing, but we do this so that
219	 *  destination LSAP of received frame is source LSAP in our view
220	 */
221	slsap_sel = fp[0] & LSAP_MASK;
222	dlsap_sel = fp[1];
223	pid       = fp[2];
224
225	if (pid & 0x80) {
226		IRDA_DEBUG(0, "%s(), extension in PID not supp!\n",
227			   __func__);
228		return;
229	}
230
231	/* Check if frame is addressed to the connectionless LSAP */
232	if ((slsap_sel != LSAP_CONNLESS) || (dlsap_sel != LSAP_CONNLESS)) {
233		IRDA_DEBUG(0, "%s(), dropping frame!\n", __func__);
234		return;
235	}
236
237	/* Search the connectionless LSAP */
238	spin_lock_irqsave(&irlmp->unconnected_lsaps->hb_spinlock, flags);
239	lsap = (struct lsap_cb *) hashbin_get_first(irlmp->unconnected_lsaps);
240	while (lsap != NULL) {
241		/*
242		 *  Check if source LSAP and dest LSAP selectors and PID match.
243		 */
244		if ((lsap->slsap_sel == slsap_sel) &&
245		    (lsap->dlsap_sel == dlsap_sel) &&
246		    (lsap->pid == pid))
247		{
248			break;
249		}
250		lsap = (struct lsap_cb *) hashbin_get_next(irlmp->unconnected_lsaps);
251	}
252	spin_unlock_irqrestore(&irlmp->unconnected_lsaps->hb_spinlock, flags);
253
254	if (lsap)
255		irlmp_connless_data_indication(lsap, skb);
256	else {
257		IRDA_DEBUG(0, "%s(), found no matching LSAP!\n", __func__);
258	}
259}
260#endif /* CONFIG_IRDA_ULTRA */
261
262/*
263 * Function irlmp_link_disconnect_indication (reason, userdata)
264 *
265 *    IrLAP has disconnected
266 *
267 */
268void irlmp_link_disconnect_indication(struct lap_cb *lap,
269				      struct irlap_cb *irlap,
270				      LAP_REASON reason,
271				      struct sk_buff *skb)
272{
273	IRDA_DEBUG(2, "%s()\n", __func__);
274
275	IRDA_ASSERT(lap != NULL, return;);
276	IRDA_ASSERT(lap->magic == LMP_LAP_MAGIC, return;);
277
278	lap->reason = reason;
279	lap->daddr = DEV_ADDR_ANY;
280
281	/* FIXME: must do something with the skb if any */
282
283	/*
284	 *  Inform station state machine
285	 */
286	irlmp_do_lap_event(lap, LM_LAP_DISCONNECT_INDICATION, NULL);
287}
288
289/*
290 * Function irlmp_link_connect_indication (qos)
291 *
292 *    Incoming LAP connection!
293 *
294 */
295void irlmp_link_connect_indication(struct lap_cb *self, __u32 saddr,
296				   __u32 daddr, struct qos_info *qos,
297				   struct sk_buff *skb)
298{
299	IRDA_DEBUG(4, "%s()\n", __func__);
300
301	/* Copy QoS settings for this session */
302	self->qos = qos;
303
304	/* Update destination device address */
305	self->daddr = daddr;
306	IRDA_ASSERT(self->saddr == saddr, return;);
307
308	irlmp_do_lap_event(self, LM_LAP_CONNECT_INDICATION, skb);
309}
310
311/*
312 * Function irlmp_link_connect_confirm (qos)
313 *
314 *    LAP connection confirmed!
315 *
316 */
317void irlmp_link_connect_confirm(struct lap_cb *self, struct qos_info *qos,
318				struct sk_buff *skb)
319{
320	IRDA_DEBUG(4, "%s()\n", __func__);
321
322	IRDA_ASSERT(self != NULL, return;);
323	IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
324	IRDA_ASSERT(qos != NULL, return;);
325
326	/* Don't need use the skb for now */
327
328	/* Copy QoS settings for this session */
329	self->qos = qos;
330
331	irlmp_do_lap_event(self, LM_LAP_CONNECT_CONFIRM, NULL);
332}
333
334/*
335 * Function irlmp_link_discovery_indication (self, log)
336 *
337 *    Device is discovering us
338 *
339 * It's not an answer to our own discoveries, just another device trying
340 * to perform discovery, but we don't want to miss the opportunity
341 * to exploit this information, because :
342 *	o We may not actively perform discovery (just passive discovery)
343 *	o This type of discovery is much more reliable. In some cases, it
344 *	  seem that less than 50% of our discoveries get an answer, while
345 *	  we always get ~100% of these.
346 *	o Make faster discovery, statistically divide time of discovery
347 *	  events by 2 (important for the latency aspect and user feel)
348 *	o Even is we do active discovery, the other node might not
349 *	  answer our discoveries (ex: Palm). The Palm will just perform
350 *	  one active discovery and connect directly to us.
351 *
352 * However, when both devices discover each other, they might attempt to
353 * connect to each other following the discovery event, and it would create
354 * collisions on the medium (SNRM battle).
355 * The "fix" for that is to disable all connection requests in IrLAP
356 * for 100ms after a discovery indication by setting the media_busy flag.
357 * Previously, we used to postpone the event which was quite ugly. Now
358 * that IrLAP takes care of this problem, just pass the event up...
359 *
360 * Jean II
361 */
362void irlmp_link_discovery_indication(struct lap_cb *self,
363				     discovery_t *discovery)
364{
365	IRDA_ASSERT(self != NULL, return;);
366	IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
367
368	/* Add to main log, cleanup */
369	irlmp_add_discovery(irlmp->cachelog, discovery);
370
371	/* Just handle it the same way as a discovery confirm,
372	 * bypass the LM_LAP state machine (see below) */
373	irlmp_discovery_confirm(irlmp->cachelog, DISCOVERY_PASSIVE);
374}
375
376/*
377 * Function irlmp_link_discovery_confirm (self, log)
378 *
379 *    Called by IrLAP with a list of discoveries after the discovery
380 *    request has been carried out. A NULL log is received if IrLAP
381 *    was unable to carry out the discovery request
382 *
383 */
384void irlmp_link_discovery_confirm(struct lap_cb *self, hashbin_t *log)
385{
386	IRDA_DEBUG(4, "%s()\n", __func__);
387
388	IRDA_ASSERT(self != NULL, return;);
389	IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
390
391	/* Add to main log, cleanup */
392	irlmp_add_discovery_log(irlmp->cachelog, log);
393
394	/* Propagate event to various LSAPs registered for it.
395	 * We bypass the LM_LAP state machine because
396	 *	1) We do it regardless of the LM_LAP state
397	 *	2) It doesn't affect the LM_LAP state
398	 *	3) Faster, slimer, simpler, ...
399	 * Jean II */
400	irlmp_discovery_confirm(irlmp->cachelog, DISCOVERY_ACTIVE);
401}
402
403#ifdef CONFIG_IRDA_CACHE_LAST_LSAP
404static inline void irlmp_update_cache(struct lap_cb *lap,
405				      struct lsap_cb *lsap)
406{
407	/* Prevent concurrent read to get garbage */
408	lap->cache.valid = FALSE;
409	/* Update cache entry */
410	lap->cache.dlsap_sel = lsap->dlsap_sel;
411	lap->cache.slsap_sel = lsap->slsap_sel;
412	lap->cache.lsap = lsap;
413	lap->cache.valid = TRUE;
414}
415#endif
416
417/*
418 * Function irlmp_find_handle (self, dlsap_sel, slsap_sel, status, queue)
419 *
420 *    Find handle associated with destination and source LSAP
421 *
422 * Any IrDA connection (LSAP/TSAP) is uniquely identified by
423 * 3 parameters, the local lsap, the remote lsap and the remote address.
424 * We may initiate multiple connections to the same remote service
425 * (they will have different local lsap), a remote device may initiate
426 * multiple connections to the same local service (they will have
427 * different remote lsap), or multiple devices may connect to the same
428 * service and may use the same remote lsap (and they will have
429 * different remote address).
430 * So, where is the remote address ? Each LAP connection is made with
431 * a single remote device, so imply a specific remote address.
432 * Jean II
433 */
434static struct lsap_cb *irlmp_find_lsap(struct lap_cb *self, __u8 dlsap_sel,
435				       __u8 slsap_sel, int status,
436				       hashbin_t *queue)
437{
438	struct lsap_cb *lsap;
439	unsigned long flags;
440
441	/*
442	 *  Optimize for the common case. We assume that the last frame
443	 *  received is in the same connection as the last one, so check in
444	 *  cache first to avoid the linear search
445	 */
446#ifdef CONFIG_IRDA_CACHE_LAST_LSAP
447	if ((self->cache.valid) &&
448	    (self->cache.slsap_sel == slsap_sel) &&
449	    (self->cache.dlsap_sel == dlsap_sel))
450	{
451		return self->cache.lsap;
452	}
453#endif
454
455	spin_lock_irqsave(&queue->hb_spinlock, flags);
456
457	lsap = (struct lsap_cb *) hashbin_get_first(queue);
458	while (lsap != NULL) {
459		/*
460		 *  If this is an incoming connection, then the destination
461		 *  LSAP selector may have been specified as LM_ANY so that
462		 *  any client can connect. In that case we only need to check
463		 *  if the source LSAP (in our view!) match!
464		 */
465		if ((status == CONNECT_CMD) &&
466		    (lsap->slsap_sel == slsap_sel) &&
467		    (lsap->dlsap_sel == LSAP_ANY)) {
468			/* This is where the dest lsap sel is set on incoming
469			 * lsaps */
470			lsap->dlsap_sel = dlsap_sel;
471			break;
472		}
473		/*
474		 *  Check if source LSAP and dest LSAP selectors match.
475		 */
476		if ((lsap->slsap_sel == slsap_sel) &&
477		    (lsap->dlsap_sel == dlsap_sel))
478			break;
479
480		lsap = (struct lsap_cb *) hashbin_get_next(queue);
481	}
482#ifdef CONFIG_IRDA_CACHE_LAST_LSAP
483	if(lsap)
484		irlmp_update_cache(self, lsap);
485#endif
486	spin_unlock_irqrestore(&queue->hb_spinlock, flags);
487
488	/* Return what we've found or NULL */
489	return lsap;
490}
v3.5.6
  1/*********************************************************************
  2 *
  3 * Filename:      irlmp_frame.c
  4 * Version:       0.9
  5 * Description:   IrLMP frame implementation
  6 * Status:        Experimental.
  7 * Author:        Dag Brattli <dagb@cs.uit.no>
  8 * Created at:    Tue Aug 19 02:09:59 1997
  9 * Modified at:   Mon Dec 13 13:41:12 1999
 10 * Modified by:   Dag Brattli <dagb@cs.uit.no>
 11 *
 12 *     Copyright (c) 1998-1999 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
 27#include <linux/skbuff.h>
 28#include <linux/kernel.h>
 29
 30#include <net/irda/irda.h>
 31#include <net/irda/irlap.h>
 32#include <net/irda/timer.h>
 33#include <net/irda/irlmp.h>
 34#include <net/irda/irlmp_frame.h>
 35#include <net/irda/discovery.h>
 36
 37static struct lsap_cb *irlmp_find_lsap(struct lap_cb *self, __u8 dlsap,
 38				       __u8 slsap, int status, hashbin_t *);
 39
 40inline void irlmp_send_data_pdu(struct lap_cb *self, __u8 dlsap, __u8 slsap,
 41				int expedited, struct sk_buff *skb)
 42{
 43	skb->data[0] = dlsap;
 44	skb->data[1] = slsap;
 45
 46	if (expedited) {
 47		IRDA_DEBUG(4, "%s(), sending expedited data\n", __func__);
 48		irlap_data_request(self->irlap, skb, TRUE);
 49	} else
 50		irlap_data_request(self->irlap, skb, FALSE);
 51}
 52
 53/*
 54 * Function irlmp_send_lcf_pdu (dlsap, slsap, opcode,skb)
 55 *
 56 *    Send Link Control Frame to IrLAP
 57 */
 58void irlmp_send_lcf_pdu(struct lap_cb *self, __u8 dlsap, __u8 slsap,
 59			__u8 opcode, struct sk_buff *skb)
 60{
 61	__u8 *frame;
 62
 63	IRDA_DEBUG(2, "%s()\n", __func__);
 64
 65	IRDA_ASSERT(self != NULL, return;);
 66	IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
 67	IRDA_ASSERT(skb != NULL, return;);
 68
 69	frame = skb->data;
 70
 71	frame[0] = dlsap | CONTROL_BIT;
 72	frame[1] = slsap;
 73
 74	frame[2] = opcode;
 75
 76	if (opcode == DISCONNECT)
 77		frame[3] = 0x01; /* Service user request */
 78	else
 79		frame[3] = 0x00; /* rsvd */
 80
 81	irlap_data_request(self->irlap, skb, FALSE);
 82}
 83
 84/*
 85 * Function irlmp_input (skb)
 86 *
 87 *    Used by IrLAP to pass received data frames to IrLMP layer
 88 *
 89 */
 90void irlmp_link_data_indication(struct lap_cb *self, struct sk_buff *skb,
 91				int unreliable)
 92{
 93	struct lsap_cb *lsap;
 94	__u8   slsap_sel;   /* Source (this) LSAP address */
 95	__u8   dlsap_sel;   /* Destination LSAP address */
 96	__u8   *fp;
 97
 98	IRDA_DEBUG(4, "%s()\n", __func__);
 99
100	IRDA_ASSERT(self != NULL, return;);
101	IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
102	IRDA_ASSERT(skb->len > 2, return;);
103
104	fp = skb->data;
105
106	/*
107	 *  The next statements may be confusing, but we do this so that
108	 *  destination LSAP of received frame is source LSAP in our view
109	 */
110	slsap_sel = fp[0] & LSAP_MASK;
111	dlsap_sel = fp[1];
112
113	/*
114	 *  Check if this is an incoming connection, since we must deal with
115	 *  it in a different way than other established connections.
116	 */
117	if ((fp[0] & CONTROL_BIT) && (fp[2] == CONNECT_CMD)) {
118		IRDA_DEBUG(3, "%s(), incoming connection, "
119			   "source LSAP=%d, dest LSAP=%d\n",
120			   __func__, slsap_sel, dlsap_sel);
121
122		/* Try to find LSAP among the unconnected LSAPs */
123		lsap = irlmp_find_lsap(self, dlsap_sel, slsap_sel, CONNECT_CMD,
124				       irlmp->unconnected_lsaps);
125
126		/* Maybe LSAP was already connected, so try one more time */
127		if (!lsap) {
128			IRDA_DEBUG(1, "%s(), incoming connection for LSAP already connected\n", __func__);
129			lsap = irlmp_find_lsap(self, dlsap_sel, slsap_sel, 0,
130					       self->lsaps);
131		}
132	} else
133		lsap = irlmp_find_lsap(self, dlsap_sel, slsap_sel, 0,
134				       self->lsaps);
135
136	if (lsap == NULL) {
137		IRDA_DEBUG(2, "IrLMP, Sorry, no LSAP for received frame!\n");
138		IRDA_DEBUG(2, "%s(), slsap_sel = %02x, dlsap_sel = %02x\n",
139			   __func__, slsap_sel, dlsap_sel);
140		if (fp[0] & CONTROL_BIT) {
141			IRDA_DEBUG(2, "%s(), received control frame %02x\n",
142				   __func__, fp[2]);
143		} else {
144			IRDA_DEBUG(2, "%s(), received data frame\n", __func__);
145		}
146		return;
147	}
148
149	/*
150	 *  Check if we received a control frame?
151	 */
152	if (fp[0] & CONTROL_BIT) {
153		switch (fp[2]) {
154		case CONNECT_CMD:
155			lsap->lap = self;
156			irlmp_do_lsap_event(lsap, LM_CONNECT_INDICATION, skb);
157			break;
158		case CONNECT_CNF:
159			irlmp_do_lsap_event(lsap, LM_CONNECT_CONFIRM, skb);
160			break;
161		case DISCONNECT:
162			IRDA_DEBUG(4, "%s(), Disconnect indication!\n",
163				   __func__);
164			irlmp_do_lsap_event(lsap, LM_DISCONNECT_INDICATION,
165					    skb);
166			break;
167		case ACCESSMODE_CMD:
168			IRDA_DEBUG(0, "Access mode cmd not implemented!\n");
169			break;
170		case ACCESSMODE_CNF:
171			IRDA_DEBUG(0, "Access mode cnf not implemented!\n");
172			break;
173		default:
174			IRDA_DEBUG(0, "%s(), Unknown control frame %02x\n",
175				   __func__, fp[2]);
176			break;
177		}
178	} else if (unreliable) {
179		/* Optimize and bypass the state machine if possible */
180		if (lsap->lsap_state == LSAP_DATA_TRANSFER_READY)
181			irlmp_udata_indication(lsap, skb);
182		else
183			irlmp_do_lsap_event(lsap, LM_UDATA_INDICATION, skb);
184	} else {
185		/* Optimize and bypass the state machine if possible */
186		if (lsap->lsap_state == LSAP_DATA_TRANSFER_READY)
187			irlmp_data_indication(lsap, skb);
188		else
189			irlmp_do_lsap_event(lsap, LM_DATA_INDICATION, skb);
190	}
191}
192
193/*
194 * Function irlmp_link_unitdata_indication (self, skb)
195 *
196 *
197 *
198 */
199#ifdef CONFIG_IRDA_ULTRA
200void irlmp_link_unitdata_indication(struct lap_cb *self, struct sk_buff *skb)
201{
202	struct lsap_cb *lsap;
203	__u8   slsap_sel;   /* Source (this) LSAP address */
204	__u8   dlsap_sel;   /* Destination LSAP address */
205	__u8   pid;         /* Protocol identifier */
206	__u8   *fp;
207	unsigned long flags;
208
209	IRDA_DEBUG(4, "%s()\n", __func__);
210
211	IRDA_ASSERT(self != NULL, return;);
212	IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
213	IRDA_ASSERT(skb->len > 2, return;);
214
215	fp = skb->data;
216
217	/*
218	 *  The next statements may be confusing, but we do this so that
219	 *  destination LSAP of received frame is source LSAP in our view
220	 */
221	slsap_sel = fp[0] & LSAP_MASK;
222	dlsap_sel = fp[1];
223	pid       = fp[2];
224
225	if (pid & 0x80) {
226		IRDA_DEBUG(0, "%s(), extension in PID not supp!\n",
227			   __func__);
228		return;
229	}
230
231	/* Check if frame is addressed to the connectionless LSAP */
232	if ((slsap_sel != LSAP_CONNLESS) || (dlsap_sel != LSAP_CONNLESS)) {
233		IRDA_DEBUG(0, "%s(), dropping frame!\n", __func__);
234		return;
235	}
236
237	/* Search the connectionless LSAP */
238	spin_lock_irqsave(&irlmp->unconnected_lsaps->hb_spinlock, flags);
239	lsap = (struct lsap_cb *) hashbin_get_first(irlmp->unconnected_lsaps);
240	while (lsap != NULL) {
241		/*
242		 *  Check if source LSAP and dest LSAP selectors and PID match.
243		 */
244		if ((lsap->slsap_sel == slsap_sel) &&
245		    (lsap->dlsap_sel == dlsap_sel) &&
246		    (lsap->pid == pid))
247		{
248			break;
249		}
250		lsap = (struct lsap_cb *) hashbin_get_next(irlmp->unconnected_lsaps);
251	}
252	spin_unlock_irqrestore(&irlmp->unconnected_lsaps->hb_spinlock, flags);
253
254	if (lsap)
255		irlmp_connless_data_indication(lsap, skb);
256	else {
257		IRDA_DEBUG(0, "%s(), found no matching LSAP!\n", __func__);
258	}
259}
260#endif /* CONFIG_IRDA_ULTRA */
261
262/*
263 * Function irlmp_link_disconnect_indication (reason, userdata)
264 *
265 *    IrLAP has disconnected
266 *
267 */
268void irlmp_link_disconnect_indication(struct lap_cb *lap,
269				      struct irlap_cb *irlap,
270				      LAP_REASON reason,
271				      struct sk_buff *skb)
272{
273	IRDA_DEBUG(2, "%s()\n", __func__);
274
275	IRDA_ASSERT(lap != NULL, return;);
276	IRDA_ASSERT(lap->magic == LMP_LAP_MAGIC, return;);
277
278	lap->reason = reason;
279	lap->daddr = DEV_ADDR_ANY;
280
281	/* FIXME: must do something with the skb if any */
282
283	/*
284	 *  Inform station state machine
285	 */
286	irlmp_do_lap_event(lap, LM_LAP_DISCONNECT_INDICATION, NULL);
287}
288
289/*
290 * Function irlmp_link_connect_indication (qos)
291 *
292 *    Incoming LAP connection!
293 *
294 */
295void irlmp_link_connect_indication(struct lap_cb *self, __u32 saddr,
296				   __u32 daddr, struct qos_info *qos,
297				   struct sk_buff *skb)
298{
299	IRDA_DEBUG(4, "%s()\n", __func__);
300
301	/* Copy QoS settings for this session */
302	self->qos = qos;
303
304	/* Update destination device address */
305	self->daddr = daddr;
306	IRDA_ASSERT(self->saddr == saddr, return;);
307
308	irlmp_do_lap_event(self, LM_LAP_CONNECT_INDICATION, skb);
309}
310
311/*
312 * Function irlmp_link_connect_confirm (qos)
313 *
314 *    LAP connection confirmed!
315 *
316 */
317void irlmp_link_connect_confirm(struct lap_cb *self, struct qos_info *qos,
318				struct sk_buff *skb)
319{
320	IRDA_DEBUG(4, "%s()\n", __func__);
321
322	IRDA_ASSERT(self != NULL, return;);
323	IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
324	IRDA_ASSERT(qos != NULL, return;);
325
326	/* Don't need use the skb for now */
327
328	/* Copy QoS settings for this session */
329	self->qos = qos;
330
331	irlmp_do_lap_event(self, LM_LAP_CONNECT_CONFIRM, NULL);
332}
333
334/*
335 * Function irlmp_link_discovery_indication (self, log)
336 *
337 *    Device is discovering us
338 *
339 * It's not an answer to our own discoveries, just another device trying
340 * to perform discovery, but we don't want to miss the opportunity
341 * to exploit this information, because :
342 *	o We may not actively perform discovery (just passive discovery)
343 *	o This type of discovery is much more reliable. In some cases, it
344 *	  seem that less than 50% of our discoveries get an answer, while
345 *	  we always get ~100% of these.
346 *	o Make faster discovery, statistically divide time of discovery
347 *	  events by 2 (important for the latency aspect and user feel)
348 *	o Even is we do active discovery, the other node might not
349 *	  answer our discoveries (ex: Palm). The Palm will just perform
350 *	  one active discovery and connect directly to us.
351 *
352 * However, when both devices discover each other, they might attempt to
353 * connect to each other following the discovery event, and it would create
354 * collisions on the medium (SNRM battle).
355 * The "fix" for that is to disable all connection requests in IrLAP
356 * for 100ms after a discovery indication by setting the media_busy flag.
357 * Previously, we used to postpone the event which was quite ugly. Now
358 * that IrLAP takes care of this problem, just pass the event up...
359 *
360 * Jean II
361 */
362void irlmp_link_discovery_indication(struct lap_cb *self,
363				     discovery_t *discovery)
364{
365	IRDA_ASSERT(self != NULL, return;);
366	IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
367
368	/* Add to main log, cleanup */
369	irlmp_add_discovery(irlmp->cachelog, discovery);
370
371	/* Just handle it the same way as a discovery confirm,
372	 * bypass the LM_LAP state machine (see below) */
373	irlmp_discovery_confirm(irlmp->cachelog, DISCOVERY_PASSIVE);
374}
375
376/*
377 * Function irlmp_link_discovery_confirm (self, log)
378 *
379 *    Called by IrLAP with a list of discoveries after the discovery
380 *    request has been carried out. A NULL log is received if IrLAP
381 *    was unable to carry out the discovery request
382 *
383 */
384void irlmp_link_discovery_confirm(struct lap_cb *self, hashbin_t *log)
385{
386	IRDA_DEBUG(4, "%s()\n", __func__);
387
388	IRDA_ASSERT(self != NULL, return;);
389	IRDA_ASSERT(self->magic == LMP_LAP_MAGIC, return;);
390
391	/* Add to main log, cleanup */
392	irlmp_add_discovery_log(irlmp->cachelog, log);
393
394	/* Propagate event to various LSAPs registered for it.
395	 * We bypass the LM_LAP state machine because
396	 *	1) We do it regardless of the LM_LAP state
397	 *	2) It doesn't affect the LM_LAP state
398	 *	3) Faster, slimer, simpler, ...
399	 * Jean II */
400	irlmp_discovery_confirm(irlmp->cachelog, DISCOVERY_ACTIVE);
401}
402
403#ifdef CONFIG_IRDA_CACHE_LAST_LSAP
404static inline void irlmp_update_cache(struct lap_cb *lap,
405				      struct lsap_cb *lsap)
406{
407	/* Prevent concurrent read to get garbage */
408	lap->cache.valid = FALSE;
409	/* Update cache entry */
410	lap->cache.dlsap_sel = lsap->dlsap_sel;
411	lap->cache.slsap_sel = lsap->slsap_sel;
412	lap->cache.lsap = lsap;
413	lap->cache.valid = TRUE;
414}
415#endif
416
417/*
418 * Function irlmp_find_handle (self, dlsap_sel, slsap_sel, status, queue)
419 *
420 *    Find handle associated with destination and source LSAP
421 *
422 * Any IrDA connection (LSAP/TSAP) is uniquely identified by
423 * 3 parameters, the local lsap, the remote lsap and the remote address.
424 * We may initiate multiple connections to the same remote service
425 * (they will have different local lsap), a remote device may initiate
426 * multiple connections to the same local service (they will have
427 * different remote lsap), or multiple devices may connect to the same
428 * service and may use the same remote lsap (and they will have
429 * different remote address).
430 * So, where is the remote address ? Each LAP connection is made with
431 * a single remote device, so imply a specific remote address.
432 * Jean II
433 */
434static struct lsap_cb *irlmp_find_lsap(struct lap_cb *self, __u8 dlsap_sel,
435				       __u8 slsap_sel, int status,
436				       hashbin_t *queue)
437{
438	struct lsap_cb *lsap;
439	unsigned long flags;
440
441	/*
442	 *  Optimize for the common case. We assume that the last frame
443	 *  received is in the same connection as the last one, so check in
444	 *  cache first to avoid the linear search
445	 */
446#ifdef CONFIG_IRDA_CACHE_LAST_LSAP
447	if ((self->cache.valid) &&
448	    (self->cache.slsap_sel == slsap_sel) &&
449	    (self->cache.dlsap_sel == dlsap_sel))
450	{
451		return self->cache.lsap;
452	}
453#endif
454
455	spin_lock_irqsave(&queue->hb_spinlock, flags);
456
457	lsap = (struct lsap_cb *) hashbin_get_first(queue);
458	while (lsap != NULL) {
459		/*
460		 *  If this is an incoming connection, then the destination
461		 *  LSAP selector may have been specified as LM_ANY so that
462		 *  any client can connect. In that case we only need to check
463		 *  if the source LSAP (in our view!) match!
464		 */
465		if ((status == CONNECT_CMD) &&
466		    (lsap->slsap_sel == slsap_sel) &&
467		    (lsap->dlsap_sel == LSAP_ANY)) {
468			/* This is where the dest lsap sel is set on incoming
469			 * lsaps */
470			lsap->dlsap_sel = dlsap_sel;
471			break;
472		}
473		/*
474		 *  Check if source LSAP and dest LSAP selectors match.
475		 */
476		if ((lsap->slsap_sel == slsap_sel) &&
477		    (lsap->dlsap_sel == dlsap_sel))
478			break;
479
480		lsap = (struct lsap_cb *) hashbin_get_next(queue);
481	}
482#ifdef CONFIG_IRDA_CACHE_LAST_LSAP
483	if(lsap)
484		irlmp_update_cache(self, lsap);
485#endif
486	spin_unlock_irqrestore(&queue->hb_spinlock, flags);
487
488	/* Return what we've found or NULL */
489	return lsap;
490}