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v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *   ALSA sequencer Timing queue handling
  4 *   Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>
  5 *
  6 * MAJOR CHANGES
  7 *   Nov. 13, 1999	Takashi Iwai <iwai@ww.uni-erlangen.de>
  8 *     - Queues are allocated dynamically via ioctl.
  9 *     - When owner client is deleted, all owned queues are deleted, too.
 10 *     - Owner of unlocked queue is kept unmodified even if it is
 11 *	 manipulated by other clients.
 12 *     - Owner field in SET_QUEUE_OWNER ioctl must be identical with the
 13 *       caller client.  i.e. Changing owner to a third client is not
 14 *       allowed.
 15 *
 16 *  Aug. 30, 2000	Takashi Iwai
 17 *     - Queues are managed in static array again, but with better way.
 18 *       The API itself is identical.
 19 *     - The queue is locked when struct snd_seq_queue pointer is returned via
 20 *       queueptr().  This pointer *MUST* be released afterward by
 21 *       queuefree(ptr).
 22 *     - Addition of experimental sync support.
 23 */
 24
 25#include <linux/init.h>
 26#include <linux/slab.h>
 27#include <sound/core.h>
 28
 29#include "seq_memory.h"
 30#include "seq_queue.h"
 31#include "seq_clientmgr.h"
 32#include "seq_fifo.h"
 33#include "seq_timer.h"
 34#include "seq_info.h"
 35
 36/* list of allocated queues */
 37static struct snd_seq_queue *queue_list[SNDRV_SEQ_MAX_QUEUES];
 38static DEFINE_SPINLOCK(queue_list_lock);
 39/* number of queues allocated */
 40static int num_queues;
 41
 42int snd_seq_queue_get_cur_queues(void)
 43{
 44	return num_queues;
 45}
 46
 47/*----------------------------------------------------------------*/
 48
 49/* assign queue id and insert to list */
 50static int queue_list_add(struct snd_seq_queue *q)
 51{
 52	int i;
 53	unsigned long flags;
 54
 55	spin_lock_irqsave(&queue_list_lock, flags);
 56	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
 57		if (! queue_list[i]) {
 58			queue_list[i] = q;
 59			q->queue = i;
 60			num_queues++;
 61			spin_unlock_irqrestore(&queue_list_lock, flags);
 62			return i;
 63		}
 64	}
 65	spin_unlock_irqrestore(&queue_list_lock, flags);
 66	return -1;
 67}
 68
 69static struct snd_seq_queue *queue_list_remove(int id, int client)
 70{
 71	struct snd_seq_queue *q;
 72	unsigned long flags;
 73
 74	spin_lock_irqsave(&queue_list_lock, flags);
 75	q = queue_list[id];
 76	if (q) {
 77		spin_lock(&q->owner_lock);
 78		if (q->owner == client) {
 79			/* found */
 80			q->klocked = 1;
 81			spin_unlock(&q->owner_lock);
 82			queue_list[id] = NULL;
 83			num_queues--;
 84			spin_unlock_irqrestore(&queue_list_lock, flags);
 85			return q;
 86		}
 87		spin_unlock(&q->owner_lock);
 88	}
 89	spin_unlock_irqrestore(&queue_list_lock, flags);
 90	return NULL;
 91}
 92
 93/*----------------------------------------------------------------*/
 94
 95/* create new queue (constructor) */
 96static struct snd_seq_queue *queue_new(int owner, int locked)
 97{
 98	struct snd_seq_queue *q;
 99
100	q = kzalloc(sizeof(*q), GFP_KERNEL);
101	if (!q)
102		return NULL;
103
104	spin_lock_init(&q->owner_lock);
105	spin_lock_init(&q->check_lock);
106	mutex_init(&q->timer_mutex);
107	snd_use_lock_init(&q->use_lock);
108	q->queue = -1;
109
110	q->tickq = snd_seq_prioq_new();
111	q->timeq = snd_seq_prioq_new();
112	q->timer = snd_seq_timer_new();
113	if (q->tickq == NULL || q->timeq == NULL || q->timer == NULL) {
114		snd_seq_prioq_delete(&q->tickq);
115		snd_seq_prioq_delete(&q->timeq);
116		snd_seq_timer_delete(&q->timer);
117		kfree(q);
118		return NULL;
119	}
120
121	q->owner = owner;
122	q->locked = locked;
123	q->klocked = 0;
124
125	return q;
126}
127
128/* delete queue (destructor) */
129static void queue_delete(struct snd_seq_queue *q)
130{
131	/* stop and release the timer */
132	mutex_lock(&q->timer_mutex);
133	snd_seq_timer_stop(q->timer);
134	snd_seq_timer_close(q);
135	mutex_unlock(&q->timer_mutex);
136	/* wait until access free */
137	snd_use_lock_sync(&q->use_lock);
138	/* release resources... */
139	snd_seq_prioq_delete(&q->tickq);
140	snd_seq_prioq_delete(&q->timeq);
141	snd_seq_timer_delete(&q->timer);
142
143	kfree(q);
144}
145
146
147/*----------------------------------------------------------------*/
148
149/* delete all existing queues */
150void snd_seq_queues_delete(void)
151{
152	int i;
153
154	/* clear list */
155	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
156		if (queue_list[i])
157			queue_delete(queue_list[i]);
158	}
159}
160
161static void queue_use(struct snd_seq_queue *queue, int client, int use);
162
163/* allocate a new queue -
164 * return pointer to new queue or ERR_PTR(-errno) for error
165 * The new queue's use_lock is set to 1. It is the caller's responsibility to
166 * call snd_use_lock_free(&q->use_lock).
167 */
168struct snd_seq_queue *snd_seq_queue_alloc(int client, int locked, unsigned int info_flags)
169{
170	struct snd_seq_queue *q;
171
172	q = queue_new(client, locked);
173	if (q == NULL)
174		return ERR_PTR(-ENOMEM);
175	q->info_flags = info_flags;
176	queue_use(q, client, 1);
177	snd_use_lock_use(&q->use_lock);
178	if (queue_list_add(q) < 0) {
179		snd_use_lock_free(&q->use_lock);
180		queue_delete(q);
181		return ERR_PTR(-ENOMEM);
182	}
183	return q;
184}
185
186/* delete a queue - queue must be owned by the client */
187int snd_seq_queue_delete(int client, int queueid)
188{
189	struct snd_seq_queue *q;
190
191	if (queueid < 0 || queueid >= SNDRV_SEQ_MAX_QUEUES)
192		return -EINVAL;
193	q = queue_list_remove(queueid, client);
194	if (q == NULL)
195		return -EINVAL;
196	queue_delete(q);
197
198	return 0;
199}
200
201
202/* return pointer to queue structure for specified id */
203struct snd_seq_queue *queueptr(int queueid)
204{
205	struct snd_seq_queue *q;
206	unsigned long flags;
207
208	if (queueid < 0 || queueid >= SNDRV_SEQ_MAX_QUEUES)
209		return NULL;
210	spin_lock_irqsave(&queue_list_lock, flags);
211	q = queue_list[queueid];
212	if (q)
213		snd_use_lock_use(&q->use_lock);
214	spin_unlock_irqrestore(&queue_list_lock, flags);
215	return q;
216}
217
218/* return the (first) queue matching with the specified name */
219struct snd_seq_queue *snd_seq_queue_find_name(char *name)
220{
221	int i;
222	struct snd_seq_queue *q;
223
224	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
225		if ((q = queueptr(i)) != NULL) {
226			if (strncmp(q->name, name, sizeof(q->name)) == 0)
227				return q;
228			queuefree(q);
229		}
230	}
231	return NULL;
232}
233
234
235/* -------------------------------------------------------- */
236
237void snd_seq_check_queue(struct snd_seq_queue *q, int atomic, int hop)
238{
239	unsigned long flags;
240	struct snd_seq_event_cell *cell;
 
 
241
242	if (q == NULL)
243		return;
244
245	/* make this function non-reentrant */
246	spin_lock_irqsave(&q->check_lock, flags);
247	if (q->check_blocked) {
248		q->check_again = 1;
249		spin_unlock_irqrestore(&q->check_lock, flags);
250		return;		/* other thread is already checking queues */
251	}
252	q->check_blocked = 1;
253	spin_unlock_irqrestore(&q->check_lock, flags);
254
255      __again:
256	/* Process tick queue... */
 
257	for (;;) {
258		cell = snd_seq_prioq_cell_out(q->tickq,
259					      &q->timer->tick.cur_tick);
260		if (!cell)
261			break;
262		snd_seq_dispatch_event(cell, atomic, hop);
263	}
264
265	/* Process time queue... */
 
266	for (;;) {
267		cell = snd_seq_prioq_cell_out(q->timeq, &q->timer->cur_time);
268		if (!cell)
269			break;
270		snd_seq_dispatch_event(cell, atomic, hop);
271	}
272
273	/* free lock */
274	spin_lock_irqsave(&q->check_lock, flags);
275	if (q->check_again) {
276		q->check_again = 0;
277		spin_unlock_irqrestore(&q->check_lock, flags);
278		goto __again;
279	}
280	q->check_blocked = 0;
281	spin_unlock_irqrestore(&q->check_lock, flags);
282}
283
284
285/* enqueue a event to singe queue */
286int snd_seq_enqueue_event(struct snd_seq_event_cell *cell, int atomic, int hop)
287{
288	int dest, err;
289	struct snd_seq_queue *q;
290
291	if (snd_BUG_ON(!cell))
292		return -EINVAL;
293	dest = cell->event.queue;	/* destination queue */
294	q = queueptr(dest);
295	if (q == NULL)
296		return -EINVAL;
297	/* handle relative time stamps, convert them into absolute */
298	if ((cell->event.flags & SNDRV_SEQ_TIME_MODE_MASK) == SNDRV_SEQ_TIME_MODE_REL) {
299		switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
300		case SNDRV_SEQ_TIME_STAMP_TICK:
301			cell->event.time.tick += q->timer->tick.cur_tick;
302			break;
303
304		case SNDRV_SEQ_TIME_STAMP_REAL:
305			snd_seq_inc_real_time(&cell->event.time.time,
306					      &q->timer->cur_time);
307			break;
308		}
309		cell->event.flags &= ~SNDRV_SEQ_TIME_MODE_MASK;
310		cell->event.flags |= SNDRV_SEQ_TIME_MODE_ABS;
311	}
312	/* enqueue event in the real-time or midi queue */
313	switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
314	case SNDRV_SEQ_TIME_STAMP_TICK:
315		err = snd_seq_prioq_cell_in(q->tickq, cell);
316		break;
317
318	case SNDRV_SEQ_TIME_STAMP_REAL:
319	default:
320		err = snd_seq_prioq_cell_in(q->timeq, cell);
321		break;
322	}
323
324	if (err < 0) {
325		queuefree(q); /* unlock */
326		return err;
327	}
328
329	/* trigger dispatching */
330	snd_seq_check_queue(q, atomic, hop);
331
332	queuefree(q); /* unlock */
333
334	return 0;
335}
336
337
338/*----------------------------------------------------------------*/
339
340static inline int check_access(struct snd_seq_queue *q, int client)
341{
342	return (q->owner == client) || (!q->locked && !q->klocked);
343}
344
345/* check if the client has permission to modify queue parameters.
346 * if it does, lock the queue
347 */
348static int queue_access_lock(struct snd_seq_queue *q, int client)
349{
350	unsigned long flags;
351	int access_ok;
352	
353	spin_lock_irqsave(&q->owner_lock, flags);
354	access_ok = check_access(q, client);
355	if (access_ok)
356		q->klocked = 1;
357	spin_unlock_irqrestore(&q->owner_lock, flags);
358	return access_ok;
359}
360
361/* unlock the queue */
362static inline void queue_access_unlock(struct snd_seq_queue *q)
363{
364	unsigned long flags;
365
366	spin_lock_irqsave(&q->owner_lock, flags);
367	q->klocked = 0;
368	spin_unlock_irqrestore(&q->owner_lock, flags);
369}
370
371/* exported - only checking permission */
372int snd_seq_queue_check_access(int queueid, int client)
373{
374	struct snd_seq_queue *q = queueptr(queueid);
375	int access_ok;
376	unsigned long flags;
377
378	if (! q)
379		return 0;
380	spin_lock_irqsave(&q->owner_lock, flags);
381	access_ok = check_access(q, client);
382	spin_unlock_irqrestore(&q->owner_lock, flags);
383	queuefree(q);
384	return access_ok;
385}
386
387/*----------------------------------------------------------------*/
388
389/*
390 * change queue's owner and permission
391 */
392int snd_seq_queue_set_owner(int queueid, int client, int locked)
393{
394	struct snd_seq_queue *q = queueptr(queueid);
 
395
396	if (q == NULL)
397		return -EINVAL;
398
399	if (! queue_access_lock(q, client)) {
400		queuefree(q);
401		return -EPERM;
402	}
403
 
404	q->locked = locked ? 1 : 0;
405	q->owner = client;
 
406	queue_access_unlock(q);
407	queuefree(q);
408
409	return 0;
410}
411
412
413/*----------------------------------------------------------------*/
414
415/* open timer -
416 * q->use mutex should be down before calling this function to avoid
417 * confliction with snd_seq_queue_use()
418 */
419int snd_seq_queue_timer_open(int queueid)
420{
421	int result = 0;
422	struct snd_seq_queue *queue;
423	struct snd_seq_timer *tmr;
424
425	queue = queueptr(queueid);
426	if (queue == NULL)
427		return -EINVAL;
428	tmr = queue->timer;
429	if ((result = snd_seq_timer_open(queue)) < 0) {
430		snd_seq_timer_defaults(tmr);
431		result = snd_seq_timer_open(queue);
432	}
433	queuefree(queue);
434	return result;
435}
436
437/* close timer -
438 * q->use mutex should be down before calling this function
439 */
440int snd_seq_queue_timer_close(int queueid)
441{
442	struct snd_seq_queue *queue;
443	int result = 0;
444
445	queue = queueptr(queueid);
446	if (queue == NULL)
447		return -EINVAL;
448	snd_seq_timer_close(queue);
449	queuefree(queue);
450	return result;
451}
452
453/* change queue tempo and ppq */
454int snd_seq_queue_timer_set_tempo(int queueid, int client,
455				  struct snd_seq_queue_tempo *info)
456{
457	struct snd_seq_queue *q = queueptr(queueid);
458	int result;
459
460	if (q == NULL)
461		return -EINVAL;
462	if (! queue_access_lock(q, client)) {
463		queuefree(q);
464		return -EPERM;
465	}
466
467	result = snd_seq_timer_set_tempo_ppq(q->timer, info->tempo, info->ppq);
468	if (result >= 0 && info->skew_base > 0)
469		result = snd_seq_timer_set_skew(q->timer, info->skew_value,
470						info->skew_base);
471	queue_access_unlock(q);
472	queuefree(q);
473	return result;
474}
475
476/* use or unuse this queue */
477static void queue_use(struct snd_seq_queue *queue, int client, int use)
478{
479	if (use) {
480		if (!test_and_set_bit(client, queue->clients_bitmap))
481			queue->clients++;
482	} else {
483		if (test_and_clear_bit(client, queue->clients_bitmap))
484			queue->clients--;
485	}
486	if (queue->clients) {
487		if (use && queue->clients == 1)
488			snd_seq_timer_defaults(queue->timer);
489		snd_seq_timer_open(queue);
490	} else {
491		snd_seq_timer_close(queue);
492	}
493}
494
495/* use or unuse this queue -
496 * if it is the first client, starts the timer.
497 * if it is not longer used by any clients, stop the timer.
498 */
499int snd_seq_queue_use(int queueid, int client, int use)
500{
501	struct snd_seq_queue *queue;
502
503	queue = queueptr(queueid);
504	if (queue == NULL)
505		return -EINVAL;
506	mutex_lock(&queue->timer_mutex);
507	queue_use(queue, client, use);
508	mutex_unlock(&queue->timer_mutex);
509	queuefree(queue);
510	return 0;
511}
512
513/*
514 * check if queue is used by the client
515 * return negative value if the queue is invalid.
516 * return 0 if not used, 1 if used.
517 */
518int snd_seq_queue_is_used(int queueid, int client)
519{
520	struct snd_seq_queue *q;
521	int result;
522
523	q = queueptr(queueid);
524	if (q == NULL)
525		return -EINVAL; /* invalid queue */
526	result = test_bit(client, q->clients_bitmap) ? 1 : 0;
527	queuefree(q);
528	return result;
529}
530
531
532/*----------------------------------------------------------------*/
533
534/* notification that client has left the system -
535 * stop the timer on all queues owned by this client
536 */
537void snd_seq_queue_client_termination(int client)
538{
539	unsigned long flags;
540	int i;
541	struct snd_seq_queue *q;
 
542
543	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
544		if ((q = queueptr(i)) == NULL)
545			continue;
546		spin_lock_irqsave(&q->owner_lock, flags);
547		if (q->owner == client)
 
548			q->klocked = 1;
549		spin_unlock_irqrestore(&q->owner_lock, flags);
550		if (q->owner == client) {
551			if (q->timer->running)
552				snd_seq_timer_stop(q->timer);
553			snd_seq_timer_reset(q->timer);
554		}
555		queuefree(q);
556	}
557}
558
559/* final stage notification -
560 * remove cells for no longer exist client (for non-owned queue)
561 * or delete this queue (for owned queue)
562 */
563void snd_seq_queue_client_leave(int client)
564{
565	int i;
566	struct snd_seq_queue *q;
567
568	/* delete own queues from queue list */
569	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
570		if ((q = queue_list_remove(i, client)) != NULL)
571			queue_delete(q);
572	}
573
574	/* remove cells from existing queues -
575	 * they are not owned by this client
576	 */
577	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
578		if ((q = queueptr(i)) == NULL)
579			continue;
580		if (test_bit(client, q->clients_bitmap)) {
581			snd_seq_prioq_leave(q->tickq, client, 0);
582			snd_seq_prioq_leave(q->timeq, client, 0);
583			snd_seq_queue_use(q->queue, client, 0);
584		}
585		queuefree(q);
586	}
587}
588
589
590
591/*----------------------------------------------------------------*/
592
593/* remove cells from all queues */
594void snd_seq_queue_client_leave_cells(int client)
595{
596	int i;
597	struct snd_seq_queue *q;
598
599	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
600		if ((q = queueptr(i)) == NULL)
601			continue;
602		snd_seq_prioq_leave(q->tickq, client, 0);
603		snd_seq_prioq_leave(q->timeq, client, 0);
604		queuefree(q);
605	}
606}
607
608/* remove cells based on flush criteria */
609void snd_seq_queue_remove_cells(int client, struct snd_seq_remove_events *info)
610{
611	int i;
612	struct snd_seq_queue *q;
613
614	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
615		if ((q = queueptr(i)) == NULL)
616			continue;
617		if (test_bit(client, q->clients_bitmap) &&
618		    (! (info->remove_mode & SNDRV_SEQ_REMOVE_DEST) ||
619		     q->queue == info->queue)) {
620			snd_seq_prioq_remove_events(q->tickq, client, info);
621			snd_seq_prioq_remove_events(q->timeq, client, info);
622		}
623		queuefree(q);
624	}
625}
626
627/*----------------------------------------------------------------*/
628
629/*
630 * send events to all subscribed ports
631 */
632static void queue_broadcast_event(struct snd_seq_queue *q, struct snd_seq_event *ev,
633				  int atomic, int hop)
634{
635	struct snd_seq_event sev;
636
637	sev = *ev;
638	
639	sev.flags = SNDRV_SEQ_TIME_STAMP_TICK|SNDRV_SEQ_TIME_MODE_ABS;
640	sev.time.tick = q->timer->tick.cur_tick;
641	sev.queue = q->queue;
642	sev.data.queue.queue = q->queue;
643
644	/* broadcast events from Timer port */
645	sev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
646	sev.source.port = SNDRV_SEQ_PORT_SYSTEM_TIMER;
647	sev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
648	snd_seq_kernel_client_dispatch(SNDRV_SEQ_CLIENT_SYSTEM, &sev, atomic, hop);
649}
650
651/*
652 * process a received queue-control event.
653 * this function is exported for seq_sync.c.
654 */
655static void snd_seq_queue_process_event(struct snd_seq_queue *q,
656					struct snd_seq_event *ev,
657					int atomic, int hop)
658{
659	switch (ev->type) {
660	case SNDRV_SEQ_EVENT_START:
661		snd_seq_prioq_leave(q->tickq, ev->source.client, 1);
662		snd_seq_prioq_leave(q->timeq, ev->source.client, 1);
663		if (! snd_seq_timer_start(q->timer))
664			queue_broadcast_event(q, ev, atomic, hop);
665		break;
666
667	case SNDRV_SEQ_EVENT_CONTINUE:
668		if (! snd_seq_timer_continue(q->timer))
669			queue_broadcast_event(q, ev, atomic, hop);
670		break;
671
672	case SNDRV_SEQ_EVENT_STOP:
673		snd_seq_timer_stop(q->timer);
674		queue_broadcast_event(q, ev, atomic, hop);
675		break;
676
677	case SNDRV_SEQ_EVENT_TEMPO:
678		snd_seq_timer_set_tempo(q->timer, ev->data.queue.param.value);
679		queue_broadcast_event(q, ev, atomic, hop);
680		break;
681
682	case SNDRV_SEQ_EVENT_SETPOS_TICK:
683		if (snd_seq_timer_set_position_tick(q->timer, ev->data.queue.param.time.tick) == 0) {
684			queue_broadcast_event(q, ev, atomic, hop);
685		}
686		break;
687
688	case SNDRV_SEQ_EVENT_SETPOS_TIME:
689		if (snd_seq_timer_set_position_time(q->timer, ev->data.queue.param.time.time) == 0) {
690			queue_broadcast_event(q, ev, atomic, hop);
691		}
692		break;
693	case SNDRV_SEQ_EVENT_QUEUE_SKEW:
694		if (snd_seq_timer_set_skew(q->timer,
695					   ev->data.queue.param.skew.value,
696					   ev->data.queue.param.skew.base) == 0) {
697			queue_broadcast_event(q, ev, atomic, hop);
698		}
699		break;
700	}
701}
702
703
704/*
705 * Queue control via timer control port:
706 * this function is exported as a callback of timer port.
707 */
708int snd_seq_control_queue(struct snd_seq_event *ev, int atomic, int hop)
709{
710	struct snd_seq_queue *q;
711
712	if (snd_BUG_ON(!ev))
713		return -EINVAL;
714	q = queueptr(ev->data.queue.queue);
715
716	if (q == NULL)
717		return -EINVAL;
718
719	if (! queue_access_lock(q, ev->source.client)) {
720		queuefree(q);
721		return -EPERM;
722	}
723
724	snd_seq_queue_process_event(q, ev, atomic, hop);
725
726	queue_access_unlock(q);
727	queuefree(q);
728	return 0;
729}
730
731
732/*----------------------------------------------------------------*/
733
734#ifdef CONFIG_SND_PROC_FS
735/* exported to seq_info.c */
736void snd_seq_info_queues_read(struct snd_info_entry *entry, 
737			      struct snd_info_buffer *buffer)
738{
739	int i, bpm;
740	struct snd_seq_queue *q;
741	struct snd_seq_timer *tmr;
 
 
742
743	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
744		if ((q = queueptr(i)) == NULL)
745			continue;
746
747		tmr = q->timer;
748		if (tmr->tempo)
749			bpm = 60000000 / tmr->tempo;
750		else
751			bpm = 0;
752
 
 
 
 
 
753		snd_iprintf(buffer, "queue %d: [%s]\n", q->queue, q->name);
754		snd_iprintf(buffer, "owned by client    : %d\n", q->owner);
755		snd_iprintf(buffer, "lock status        : %s\n", q->locked ? "Locked" : "Free");
756		snd_iprintf(buffer, "queued time events : %d\n", snd_seq_prioq_avail(q->timeq));
757		snd_iprintf(buffer, "queued tick events : %d\n", snd_seq_prioq_avail(q->tickq));
758		snd_iprintf(buffer, "timer state        : %s\n", tmr->running ? "Running" : "Stopped");
759		snd_iprintf(buffer, "timer PPQ          : %d\n", tmr->ppq);
760		snd_iprintf(buffer, "current tempo      : %d\n", tmr->tempo);
761		snd_iprintf(buffer, "current BPM        : %d\n", bpm);
762		snd_iprintf(buffer, "current time       : %d.%09d s\n", tmr->cur_time.tv_sec, tmr->cur_time.tv_nsec);
763		snd_iprintf(buffer, "current tick       : %d\n", tmr->tick.cur_tick);
764		snd_iprintf(buffer, "\n");
765		queuefree(q);
766	}
767}
768#endif /* CONFIG_SND_PROC_FS */
769
v5.9
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *   ALSA sequencer Timing queue handling
  4 *   Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>
  5 *
  6 * MAJOR CHANGES
  7 *   Nov. 13, 1999	Takashi Iwai <iwai@ww.uni-erlangen.de>
  8 *     - Queues are allocated dynamically via ioctl.
  9 *     - When owner client is deleted, all owned queues are deleted, too.
 10 *     - Owner of unlocked queue is kept unmodified even if it is
 11 *	 manipulated by other clients.
 12 *     - Owner field in SET_QUEUE_OWNER ioctl must be identical with the
 13 *       caller client.  i.e. Changing owner to a third client is not
 14 *       allowed.
 15 *
 16 *  Aug. 30, 2000	Takashi Iwai
 17 *     - Queues are managed in static array again, but with better way.
 18 *       The API itself is identical.
 19 *     - The queue is locked when struct snd_seq_queue pointer is returned via
 20 *       queueptr().  This pointer *MUST* be released afterward by
 21 *       queuefree(ptr).
 22 *     - Addition of experimental sync support.
 23 */
 24
 25#include <linux/init.h>
 26#include <linux/slab.h>
 27#include <sound/core.h>
 28
 29#include "seq_memory.h"
 30#include "seq_queue.h"
 31#include "seq_clientmgr.h"
 32#include "seq_fifo.h"
 33#include "seq_timer.h"
 34#include "seq_info.h"
 35
 36/* list of allocated queues */
 37static struct snd_seq_queue *queue_list[SNDRV_SEQ_MAX_QUEUES];
 38static DEFINE_SPINLOCK(queue_list_lock);
 39/* number of queues allocated */
 40static int num_queues;
 41
 42int snd_seq_queue_get_cur_queues(void)
 43{
 44	return num_queues;
 45}
 46
 47/*----------------------------------------------------------------*/
 48
 49/* assign queue id and insert to list */
 50static int queue_list_add(struct snd_seq_queue *q)
 51{
 52	int i;
 53	unsigned long flags;
 54
 55	spin_lock_irqsave(&queue_list_lock, flags);
 56	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
 57		if (! queue_list[i]) {
 58			queue_list[i] = q;
 59			q->queue = i;
 60			num_queues++;
 61			spin_unlock_irqrestore(&queue_list_lock, flags);
 62			return i;
 63		}
 64	}
 65	spin_unlock_irqrestore(&queue_list_lock, flags);
 66	return -1;
 67}
 68
 69static struct snd_seq_queue *queue_list_remove(int id, int client)
 70{
 71	struct snd_seq_queue *q;
 72	unsigned long flags;
 73
 74	spin_lock_irqsave(&queue_list_lock, flags);
 75	q = queue_list[id];
 76	if (q) {
 77		spin_lock(&q->owner_lock);
 78		if (q->owner == client) {
 79			/* found */
 80			q->klocked = 1;
 81			spin_unlock(&q->owner_lock);
 82			queue_list[id] = NULL;
 83			num_queues--;
 84			spin_unlock_irqrestore(&queue_list_lock, flags);
 85			return q;
 86		}
 87		spin_unlock(&q->owner_lock);
 88	}
 89	spin_unlock_irqrestore(&queue_list_lock, flags);
 90	return NULL;
 91}
 92
 93/*----------------------------------------------------------------*/
 94
 95/* create new queue (constructor) */
 96static struct snd_seq_queue *queue_new(int owner, int locked)
 97{
 98	struct snd_seq_queue *q;
 99
100	q = kzalloc(sizeof(*q), GFP_KERNEL);
101	if (!q)
102		return NULL;
103
104	spin_lock_init(&q->owner_lock);
105	spin_lock_init(&q->check_lock);
106	mutex_init(&q->timer_mutex);
107	snd_use_lock_init(&q->use_lock);
108	q->queue = -1;
109
110	q->tickq = snd_seq_prioq_new();
111	q->timeq = snd_seq_prioq_new();
112	q->timer = snd_seq_timer_new();
113	if (q->tickq == NULL || q->timeq == NULL || q->timer == NULL) {
114		snd_seq_prioq_delete(&q->tickq);
115		snd_seq_prioq_delete(&q->timeq);
116		snd_seq_timer_delete(&q->timer);
117		kfree(q);
118		return NULL;
119	}
120
121	q->owner = owner;
122	q->locked = locked;
123	q->klocked = 0;
124
125	return q;
126}
127
128/* delete queue (destructor) */
129static void queue_delete(struct snd_seq_queue *q)
130{
131	/* stop and release the timer */
132	mutex_lock(&q->timer_mutex);
133	snd_seq_timer_stop(q->timer);
134	snd_seq_timer_close(q);
135	mutex_unlock(&q->timer_mutex);
136	/* wait until access free */
137	snd_use_lock_sync(&q->use_lock);
138	/* release resources... */
139	snd_seq_prioq_delete(&q->tickq);
140	snd_seq_prioq_delete(&q->timeq);
141	snd_seq_timer_delete(&q->timer);
142
143	kfree(q);
144}
145
146
147/*----------------------------------------------------------------*/
148
149/* delete all existing queues */
150void snd_seq_queues_delete(void)
151{
152	int i;
153
154	/* clear list */
155	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
156		if (queue_list[i])
157			queue_delete(queue_list[i]);
158	}
159}
160
161static void queue_use(struct snd_seq_queue *queue, int client, int use);
162
163/* allocate a new queue -
164 * return pointer to new queue or ERR_PTR(-errno) for error
165 * The new queue's use_lock is set to 1. It is the caller's responsibility to
166 * call snd_use_lock_free(&q->use_lock).
167 */
168struct snd_seq_queue *snd_seq_queue_alloc(int client, int locked, unsigned int info_flags)
169{
170	struct snd_seq_queue *q;
171
172	q = queue_new(client, locked);
173	if (q == NULL)
174		return ERR_PTR(-ENOMEM);
175	q->info_flags = info_flags;
176	queue_use(q, client, 1);
177	snd_use_lock_use(&q->use_lock);
178	if (queue_list_add(q) < 0) {
179		snd_use_lock_free(&q->use_lock);
180		queue_delete(q);
181		return ERR_PTR(-ENOMEM);
182	}
183	return q;
184}
185
186/* delete a queue - queue must be owned by the client */
187int snd_seq_queue_delete(int client, int queueid)
188{
189	struct snd_seq_queue *q;
190
191	if (queueid < 0 || queueid >= SNDRV_SEQ_MAX_QUEUES)
192		return -EINVAL;
193	q = queue_list_remove(queueid, client);
194	if (q == NULL)
195		return -EINVAL;
196	queue_delete(q);
197
198	return 0;
199}
200
201
202/* return pointer to queue structure for specified id */
203struct snd_seq_queue *queueptr(int queueid)
204{
205	struct snd_seq_queue *q;
206	unsigned long flags;
207
208	if (queueid < 0 || queueid >= SNDRV_SEQ_MAX_QUEUES)
209		return NULL;
210	spin_lock_irqsave(&queue_list_lock, flags);
211	q = queue_list[queueid];
212	if (q)
213		snd_use_lock_use(&q->use_lock);
214	spin_unlock_irqrestore(&queue_list_lock, flags);
215	return q;
216}
217
218/* return the (first) queue matching with the specified name */
219struct snd_seq_queue *snd_seq_queue_find_name(char *name)
220{
221	int i;
222	struct snd_seq_queue *q;
223
224	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
225		if ((q = queueptr(i)) != NULL) {
226			if (strncmp(q->name, name, sizeof(q->name)) == 0)
227				return q;
228			queuefree(q);
229		}
230	}
231	return NULL;
232}
233
234
235/* -------------------------------------------------------- */
236
237void snd_seq_check_queue(struct snd_seq_queue *q, int atomic, int hop)
238{
239	unsigned long flags;
240	struct snd_seq_event_cell *cell;
241	snd_seq_tick_time_t cur_tick;
242	snd_seq_real_time_t cur_time;
243
244	if (q == NULL)
245		return;
246
247	/* make this function non-reentrant */
248	spin_lock_irqsave(&q->check_lock, flags);
249	if (q->check_blocked) {
250		q->check_again = 1;
251		spin_unlock_irqrestore(&q->check_lock, flags);
252		return;		/* other thread is already checking queues */
253	}
254	q->check_blocked = 1;
255	spin_unlock_irqrestore(&q->check_lock, flags);
256
257      __again:
258	/* Process tick queue... */
259	cur_tick = snd_seq_timer_get_cur_tick(q->timer);
260	for (;;) {
261		cell = snd_seq_prioq_cell_out(q->tickq, &cur_tick);
 
262		if (!cell)
263			break;
264		snd_seq_dispatch_event(cell, atomic, hop);
265	}
266
267	/* Process time queue... */
268	cur_time = snd_seq_timer_get_cur_time(q->timer, false);
269	for (;;) {
270		cell = snd_seq_prioq_cell_out(q->timeq, &cur_time);
271		if (!cell)
272			break;
273		snd_seq_dispatch_event(cell, atomic, hop);
274	}
275
276	/* free lock */
277	spin_lock_irqsave(&q->check_lock, flags);
278	if (q->check_again) {
279		q->check_again = 0;
280		spin_unlock_irqrestore(&q->check_lock, flags);
281		goto __again;
282	}
283	q->check_blocked = 0;
284	spin_unlock_irqrestore(&q->check_lock, flags);
285}
286
287
288/* enqueue a event to singe queue */
289int snd_seq_enqueue_event(struct snd_seq_event_cell *cell, int atomic, int hop)
290{
291	int dest, err;
292	struct snd_seq_queue *q;
293
294	if (snd_BUG_ON(!cell))
295		return -EINVAL;
296	dest = cell->event.queue;	/* destination queue */
297	q = queueptr(dest);
298	if (q == NULL)
299		return -EINVAL;
300	/* handle relative time stamps, convert them into absolute */
301	if ((cell->event.flags & SNDRV_SEQ_TIME_MODE_MASK) == SNDRV_SEQ_TIME_MODE_REL) {
302		switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
303		case SNDRV_SEQ_TIME_STAMP_TICK:
304			cell->event.time.tick += q->timer->tick.cur_tick;
305			break;
306
307		case SNDRV_SEQ_TIME_STAMP_REAL:
308			snd_seq_inc_real_time(&cell->event.time.time,
309					      &q->timer->cur_time);
310			break;
311		}
312		cell->event.flags &= ~SNDRV_SEQ_TIME_MODE_MASK;
313		cell->event.flags |= SNDRV_SEQ_TIME_MODE_ABS;
314	}
315	/* enqueue event in the real-time or midi queue */
316	switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
317	case SNDRV_SEQ_TIME_STAMP_TICK:
318		err = snd_seq_prioq_cell_in(q->tickq, cell);
319		break;
320
321	case SNDRV_SEQ_TIME_STAMP_REAL:
322	default:
323		err = snd_seq_prioq_cell_in(q->timeq, cell);
324		break;
325	}
326
327	if (err < 0) {
328		queuefree(q); /* unlock */
329		return err;
330	}
331
332	/* trigger dispatching */
333	snd_seq_check_queue(q, atomic, hop);
334
335	queuefree(q); /* unlock */
336
337	return 0;
338}
339
340
341/*----------------------------------------------------------------*/
342
343static inline int check_access(struct snd_seq_queue *q, int client)
344{
345	return (q->owner == client) || (!q->locked && !q->klocked);
346}
347
348/* check if the client has permission to modify queue parameters.
349 * if it does, lock the queue
350 */
351static int queue_access_lock(struct snd_seq_queue *q, int client)
352{
353	unsigned long flags;
354	int access_ok;
355	
356	spin_lock_irqsave(&q->owner_lock, flags);
357	access_ok = check_access(q, client);
358	if (access_ok)
359		q->klocked = 1;
360	spin_unlock_irqrestore(&q->owner_lock, flags);
361	return access_ok;
362}
363
364/* unlock the queue */
365static inline void queue_access_unlock(struct snd_seq_queue *q)
366{
367	unsigned long flags;
368
369	spin_lock_irqsave(&q->owner_lock, flags);
370	q->klocked = 0;
371	spin_unlock_irqrestore(&q->owner_lock, flags);
372}
373
374/* exported - only checking permission */
375int snd_seq_queue_check_access(int queueid, int client)
376{
377	struct snd_seq_queue *q = queueptr(queueid);
378	int access_ok;
379	unsigned long flags;
380
381	if (! q)
382		return 0;
383	spin_lock_irqsave(&q->owner_lock, flags);
384	access_ok = check_access(q, client);
385	spin_unlock_irqrestore(&q->owner_lock, flags);
386	queuefree(q);
387	return access_ok;
388}
389
390/*----------------------------------------------------------------*/
391
392/*
393 * change queue's owner and permission
394 */
395int snd_seq_queue_set_owner(int queueid, int client, int locked)
396{
397	struct snd_seq_queue *q = queueptr(queueid);
398	unsigned long flags;
399
400	if (q == NULL)
401		return -EINVAL;
402
403	if (! queue_access_lock(q, client)) {
404		queuefree(q);
405		return -EPERM;
406	}
407
408	spin_lock_irqsave(&q->owner_lock, flags);
409	q->locked = locked ? 1 : 0;
410	q->owner = client;
411	spin_unlock_irqrestore(&q->owner_lock, flags);
412	queue_access_unlock(q);
413	queuefree(q);
414
415	return 0;
416}
417
418
419/*----------------------------------------------------------------*/
420
421/* open timer -
422 * q->use mutex should be down before calling this function to avoid
423 * confliction with snd_seq_queue_use()
424 */
425int snd_seq_queue_timer_open(int queueid)
426{
427	int result = 0;
428	struct snd_seq_queue *queue;
429	struct snd_seq_timer *tmr;
430
431	queue = queueptr(queueid);
432	if (queue == NULL)
433		return -EINVAL;
434	tmr = queue->timer;
435	if ((result = snd_seq_timer_open(queue)) < 0) {
436		snd_seq_timer_defaults(tmr);
437		result = snd_seq_timer_open(queue);
438	}
439	queuefree(queue);
440	return result;
441}
442
443/* close timer -
444 * q->use mutex should be down before calling this function
445 */
446int snd_seq_queue_timer_close(int queueid)
447{
448	struct snd_seq_queue *queue;
449	int result = 0;
450
451	queue = queueptr(queueid);
452	if (queue == NULL)
453		return -EINVAL;
454	snd_seq_timer_close(queue);
455	queuefree(queue);
456	return result;
457}
458
459/* change queue tempo and ppq */
460int snd_seq_queue_timer_set_tempo(int queueid, int client,
461				  struct snd_seq_queue_tempo *info)
462{
463	struct snd_seq_queue *q = queueptr(queueid);
464	int result;
465
466	if (q == NULL)
467		return -EINVAL;
468	if (! queue_access_lock(q, client)) {
469		queuefree(q);
470		return -EPERM;
471	}
472
473	result = snd_seq_timer_set_tempo_ppq(q->timer, info->tempo, info->ppq);
474	if (result >= 0 && info->skew_base > 0)
475		result = snd_seq_timer_set_skew(q->timer, info->skew_value,
476						info->skew_base);
477	queue_access_unlock(q);
478	queuefree(q);
479	return result;
480}
481
482/* use or unuse this queue */
483static void queue_use(struct snd_seq_queue *queue, int client, int use)
484{
485	if (use) {
486		if (!test_and_set_bit(client, queue->clients_bitmap))
487			queue->clients++;
488	} else {
489		if (test_and_clear_bit(client, queue->clients_bitmap))
490			queue->clients--;
491	}
492	if (queue->clients) {
493		if (use && queue->clients == 1)
494			snd_seq_timer_defaults(queue->timer);
495		snd_seq_timer_open(queue);
496	} else {
497		snd_seq_timer_close(queue);
498	}
499}
500
501/* use or unuse this queue -
502 * if it is the first client, starts the timer.
503 * if it is not longer used by any clients, stop the timer.
504 */
505int snd_seq_queue_use(int queueid, int client, int use)
506{
507	struct snd_seq_queue *queue;
508
509	queue = queueptr(queueid);
510	if (queue == NULL)
511		return -EINVAL;
512	mutex_lock(&queue->timer_mutex);
513	queue_use(queue, client, use);
514	mutex_unlock(&queue->timer_mutex);
515	queuefree(queue);
516	return 0;
517}
518
519/*
520 * check if queue is used by the client
521 * return negative value if the queue is invalid.
522 * return 0 if not used, 1 if used.
523 */
524int snd_seq_queue_is_used(int queueid, int client)
525{
526	struct snd_seq_queue *q;
527	int result;
528
529	q = queueptr(queueid);
530	if (q == NULL)
531		return -EINVAL; /* invalid queue */
532	result = test_bit(client, q->clients_bitmap) ? 1 : 0;
533	queuefree(q);
534	return result;
535}
536
537
538/*----------------------------------------------------------------*/
539
540/* notification that client has left the system -
541 * stop the timer on all queues owned by this client
542 */
543void snd_seq_queue_client_termination(int client)
544{
545	unsigned long flags;
546	int i;
547	struct snd_seq_queue *q;
548	bool matched;
549
550	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
551		if ((q = queueptr(i)) == NULL)
552			continue;
553		spin_lock_irqsave(&q->owner_lock, flags);
554		matched = (q->owner == client);
555		if (matched)
556			q->klocked = 1;
557		spin_unlock_irqrestore(&q->owner_lock, flags);
558		if (matched) {
559			if (q->timer->running)
560				snd_seq_timer_stop(q->timer);
561			snd_seq_timer_reset(q->timer);
562		}
563		queuefree(q);
564	}
565}
566
567/* final stage notification -
568 * remove cells for no longer exist client (for non-owned queue)
569 * or delete this queue (for owned queue)
570 */
571void snd_seq_queue_client_leave(int client)
572{
573	int i;
574	struct snd_seq_queue *q;
575
576	/* delete own queues from queue list */
577	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
578		if ((q = queue_list_remove(i, client)) != NULL)
579			queue_delete(q);
580	}
581
582	/* remove cells from existing queues -
583	 * they are not owned by this client
584	 */
585	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
586		if ((q = queueptr(i)) == NULL)
587			continue;
588		if (test_bit(client, q->clients_bitmap)) {
589			snd_seq_prioq_leave(q->tickq, client, 0);
590			snd_seq_prioq_leave(q->timeq, client, 0);
591			snd_seq_queue_use(q->queue, client, 0);
592		}
593		queuefree(q);
594	}
595}
596
597
598
599/*----------------------------------------------------------------*/
600
601/* remove cells from all queues */
602void snd_seq_queue_client_leave_cells(int client)
603{
604	int i;
605	struct snd_seq_queue *q;
606
607	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
608		if ((q = queueptr(i)) == NULL)
609			continue;
610		snd_seq_prioq_leave(q->tickq, client, 0);
611		snd_seq_prioq_leave(q->timeq, client, 0);
612		queuefree(q);
613	}
614}
615
616/* remove cells based on flush criteria */
617void snd_seq_queue_remove_cells(int client, struct snd_seq_remove_events *info)
618{
619	int i;
620	struct snd_seq_queue *q;
621
622	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
623		if ((q = queueptr(i)) == NULL)
624			continue;
625		if (test_bit(client, q->clients_bitmap) &&
626		    (! (info->remove_mode & SNDRV_SEQ_REMOVE_DEST) ||
627		     q->queue == info->queue)) {
628			snd_seq_prioq_remove_events(q->tickq, client, info);
629			snd_seq_prioq_remove_events(q->timeq, client, info);
630		}
631		queuefree(q);
632	}
633}
634
635/*----------------------------------------------------------------*/
636
637/*
638 * send events to all subscribed ports
639 */
640static void queue_broadcast_event(struct snd_seq_queue *q, struct snd_seq_event *ev,
641				  int atomic, int hop)
642{
643	struct snd_seq_event sev;
644
645	sev = *ev;
646	
647	sev.flags = SNDRV_SEQ_TIME_STAMP_TICK|SNDRV_SEQ_TIME_MODE_ABS;
648	sev.time.tick = q->timer->tick.cur_tick;
649	sev.queue = q->queue;
650	sev.data.queue.queue = q->queue;
651
652	/* broadcast events from Timer port */
653	sev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
654	sev.source.port = SNDRV_SEQ_PORT_SYSTEM_TIMER;
655	sev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
656	snd_seq_kernel_client_dispatch(SNDRV_SEQ_CLIENT_SYSTEM, &sev, atomic, hop);
657}
658
659/*
660 * process a received queue-control event.
661 * this function is exported for seq_sync.c.
662 */
663static void snd_seq_queue_process_event(struct snd_seq_queue *q,
664					struct snd_seq_event *ev,
665					int atomic, int hop)
666{
667	switch (ev->type) {
668	case SNDRV_SEQ_EVENT_START:
669		snd_seq_prioq_leave(q->tickq, ev->source.client, 1);
670		snd_seq_prioq_leave(q->timeq, ev->source.client, 1);
671		if (! snd_seq_timer_start(q->timer))
672			queue_broadcast_event(q, ev, atomic, hop);
673		break;
674
675	case SNDRV_SEQ_EVENT_CONTINUE:
676		if (! snd_seq_timer_continue(q->timer))
677			queue_broadcast_event(q, ev, atomic, hop);
678		break;
679
680	case SNDRV_SEQ_EVENT_STOP:
681		snd_seq_timer_stop(q->timer);
682		queue_broadcast_event(q, ev, atomic, hop);
683		break;
684
685	case SNDRV_SEQ_EVENT_TEMPO:
686		snd_seq_timer_set_tempo(q->timer, ev->data.queue.param.value);
687		queue_broadcast_event(q, ev, atomic, hop);
688		break;
689
690	case SNDRV_SEQ_EVENT_SETPOS_TICK:
691		if (snd_seq_timer_set_position_tick(q->timer, ev->data.queue.param.time.tick) == 0) {
692			queue_broadcast_event(q, ev, atomic, hop);
693		}
694		break;
695
696	case SNDRV_SEQ_EVENT_SETPOS_TIME:
697		if (snd_seq_timer_set_position_time(q->timer, ev->data.queue.param.time.time) == 0) {
698			queue_broadcast_event(q, ev, atomic, hop);
699		}
700		break;
701	case SNDRV_SEQ_EVENT_QUEUE_SKEW:
702		if (snd_seq_timer_set_skew(q->timer,
703					   ev->data.queue.param.skew.value,
704					   ev->data.queue.param.skew.base) == 0) {
705			queue_broadcast_event(q, ev, atomic, hop);
706		}
707		break;
708	}
709}
710
711
712/*
713 * Queue control via timer control port:
714 * this function is exported as a callback of timer port.
715 */
716int snd_seq_control_queue(struct snd_seq_event *ev, int atomic, int hop)
717{
718	struct snd_seq_queue *q;
719
720	if (snd_BUG_ON(!ev))
721		return -EINVAL;
722	q = queueptr(ev->data.queue.queue);
723
724	if (q == NULL)
725		return -EINVAL;
726
727	if (! queue_access_lock(q, ev->source.client)) {
728		queuefree(q);
729		return -EPERM;
730	}
731
732	snd_seq_queue_process_event(q, ev, atomic, hop);
733
734	queue_access_unlock(q);
735	queuefree(q);
736	return 0;
737}
738
739
740/*----------------------------------------------------------------*/
741
742#ifdef CONFIG_SND_PROC_FS
743/* exported to seq_info.c */
744void snd_seq_info_queues_read(struct snd_info_entry *entry, 
745			      struct snd_info_buffer *buffer)
746{
747	int i, bpm;
748	struct snd_seq_queue *q;
749	struct snd_seq_timer *tmr;
750	bool locked;
751	int owner;
752
753	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
754		if ((q = queueptr(i)) == NULL)
755			continue;
756
757		tmr = q->timer;
758		if (tmr->tempo)
759			bpm = 60000000 / tmr->tempo;
760		else
761			bpm = 0;
762
763		spin_lock_irq(&q->owner_lock);
764		locked = q->locked;
765		owner = q->owner;
766		spin_unlock_irq(&q->owner_lock);
767
768		snd_iprintf(buffer, "queue %d: [%s]\n", q->queue, q->name);
769		snd_iprintf(buffer, "owned by client    : %d\n", owner);
770		snd_iprintf(buffer, "lock status        : %s\n", locked ? "Locked" : "Free");
771		snd_iprintf(buffer, "queued time events : %d\n", snd_seq_prioq_avail(q->timeq));
772		snd_iprintf(buffer, "queued tick events : %d\n", snd_seq_prioq_avail(q->tickq));
773		snd_iprintf(buffer, "timer state        : %s\n", tmr->running ? "Running" : "Stopped");
774		snd_iprintf(buffer, "timer PPQ          : %d\n", tmr->ppq);
775		snd_iprintf(buffer, "current tempo      : %d\n", tmr->tempo);
776		snd_iprintf(buffer, "current BPM        : %d\n", bpm);
777		snd_iprintf(buffer, "current time       : %d.%09d s\n", tmr->cur_time.tv_sec, tmr->cur_time.tv_nsec);
778		snd_iprintf(buffer, "current tick       : %d\n", tmr->tick.cur_tick);
779		snd_iprintf(buffer, "\n");
780		queuefree(q);
781	}
782}
783#endif /* CONFIG_SND_PROC_FS */
784