xref: /linux/sound/core/seq/seq_clientmgr.c (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
1 /*
2  *  ALSA sequencer Client Manager
3  *  Copyright (c) 1998-2001 by Frank van de Pol <fvdpol@coil.demon.nl>
4  *                             Jaroslav Kysela <perex@suse.cz>
5  *                             Takashi Iwai <tiwai@suse.de>
6  *
7  *
8  *   This program is free software; you can redistribute it and/or modify
9  *   it under the terms of the GNU General Public License as published by
10  *   the Free Software Foundation; either version 2 of the License, or
11  *   (at your option) any later version.
12  *
13  *   This program is distributed in the hope that it will be useful,
14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *   GNU General Public License for more details.
17  *
18  *   You should have received a copy of the GNU General Public License
19  *   along with this program; if not, write to the Free Software
20  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
21  *
22  */
23 
24 #include <sound/driver.h>
25 #include <linux/init.h>
26 #include <linux/smp_lock.h>
27 #include <linux/slab.h>
28 #include <sound/core.h>
29 #include <sound/minors.h>
30 #include <linux/kmod.h>
31 
32 #include <sound/seq_kernel.h>
33 #include "seq_clientmgr.h"
34 #include "seq_memory.h"
35 #include "seq_queue.h"
36 #include "seq_timer.h"
37 #include "seq_info.h"
38 #include "seq_system.h"
39 #include <sound/seq_device.h>
40 #ifdef CONFIG_COMPAT
41 #include <linux/compat.h>
42 #endif
43 
44 /* Client Manager
45 
46  * this module handles the connections of userland and kernel clients
47  *
48  */
49 
50 /*
51  * There are four ranges of client numbers (last two shared):
52  * 0..15: global clients
53  * 16..127: statically allocated client numbers for cards 0..27
54  * 128..191: dynamically allocated client numbers for cards 28..31
55  * 128..191: dynamically allocated client numbers for applications
56  */
57 
58 /* number of kernel non-card clients */
59 #define SNDRV_SEQ_GLOBAL_CLIENTS	16
60 /* clients per cards, for static clients */
61 #define SNDRV_SEQ_CLIENTS_PER_CARD	4
62 /* dynamically allocated client numbers (both kernel drivers and user space) */
63 #define SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN	128
64 
65 #define SNDRV_SEQ_LFLG_INPUT	0x0001
66 #define SNDRV_SEQ_LFLG_OUTPUT	0x0002
67 #define SNDRV_SEQ_LFLG_OPEN	(SNDRV_SEQ_LFLG_INPUT|SNDRV_SEQ_LFLG_OUTPUT)
68 
69 static DEFINE_SPINLOCK(clients_lock);
70 static DEFINE_MUTEX(register_mutex);
71 
72 /*
73  * client table
74  */
75 static char clienttablock[SNDRV_SEQ_MAX_CLIENTS];
76 static struct snd_seq_client *clienttab[SNDRV_SEQ_MAX_CLIENTS];
77 static struct snd_seq_usage client_usage;
78 
79 /*
80  * prototypes
81  */
82 static int bounce_error_event(struct snd_seq_client *client,
83 			      struct snd_seq_event *event,
84 			      int err, int atomic, int hop);
85 static int snd_seq_deliver_single_event(struct snd_seq_client *client,
86 					struct snd_seq_event *event,
87 					int filter, int atomic, int hop);
88 
89 /*
90  */
91 
92 static inline mm_segment_t snd_enter_user(void)
93 {
94 	mm_segment_t fs = get_fs();
95 	set_fs(get_ds());
96 	return fs;
97 }
98 
99 static inline void snd_leave_user(mm_segment_t fs)
100 {
101 	set_fs(fs);
102 }
103 
104 /*
105  */
106 static inline unsigned short snd_seq_file_flags(struct file *file)
107 {
108         switch (file->f_mode & (FMODE_READ | FMODE_WRITE)) {
109         case FMODE_WRITE:
110                 return SNDRV_SEQ_LFLG_OUTPUT;
111         case FMODE_READ:
112                 return SNDRV_SEQ_LFLG_INPUT;
113         default:
114                 return SNDRV_SEQ_LFLG_OPEN;
115         }
116 }
117 
118 static inline int snd_seq_write_pool_allocated(struct snd_seq_client *client)
119 {
120 	return snd_seq_total_cells(client->pool) > 0;
121 }
122 
123 /* return pointer to client structure for specified id */
124 static struct snd_seq_client *clientptr(int clientid)
125 {
126 	if (clientid < 0 || clientid >= SNDRV_SEQ_MAX_CLIENTS) {
127 		snd_printd("Seq: oops. Trying to get pointer to client %d\n",
128 			   clientid);
129 		return NULL;
130 	}
131 	return clienttab[clientid];
132 }
133 
134 extern int seq_client_load[];
135 
136 struct snd_seq_client *snd_seq_client_use_ptr(int clientid)
137 {
138 	unsigned long flags;
139 	struct snd_seq_client *client;
140 
141 	if (clientid < 0 || clientid >= SNDRV_SEQ_MAX_CLIENTS) {
142 		snd_printd("Seq: oops. Trying to get pointer to client %d\n",
143 			   clientid);
144 		return NULL;
145 	}
146 	spin_lock_irqsave(&clients_lock, flags);
147 	client = clientptr(clientid);
148 	if (client)
149 		goto __lock;
150 	if (clienttablock[clientid]) {
151 		spin_unlock_irqrestore(&clients_lock, flags);
152 		return NULL;
153 	}
154 	spin_unlock_irqrestore(&clients_lock, flags);
155 #ifdef CONFIG_KMOD
156 	if (!in_interrupt() && current->fs->root) {
157 		static char client_requested[SNDRV_SEQ_GLOBAL_CLIENTS];
158 		static char card_requested[SNDRV_CARDS];
159 		if (clientid < SNDRV_SEQ_GLOBAL_CLIENTS) {
160 			int idx;
161 
162 			if (! client_requested[clientid] && current->fs->root) {
163 				client_requested[clientid] = 1;
164 				for (idx = 0; idx < 15; idx++) {
165 					if (seq_client_load[idx] < 0)
166 						break;
167 					if (seq_client_load[idx] == clientid) {
168 						request_module("snd-seq-client-%i",
169 							       clientid);
170 						break;
171 					}
172 				}
173 			}
174 		} else if (clientid < SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN) {
175 			int card = (clientid - SNDRV_SEQ_GLOBAL_CLIENTS) /
176 				SNDRV_SEQ_CLIENTS_PER_CARD;
177 			if (card < snd_ecards_limit) {
178 				if (! card_requested[card]) {
179 					card_requested[card] = 1;
180 					snd_request_card(card);
181 				}
182 				snd_seq_device_load_drivers();
183 			}
184 		}
185 		spin_lock_irqsave(&clients_lock, flags);
186 		client = clientptr(clientid);
187 		if (client)
188 			goto __lock;
189 		spin_unlock_irqrestore(&clients_lock, flags);
190 	}
191 #endif
192 	return NULL;
193 
194       __lock:
195 	snd_use_lock_use(&client->use_lock);
196 	spin_unlock_irqrestore(&clients_lock, flags);
197 	return client;
198 }
199 
200 static void usage_alloc(struct snd_seq_usage *res, int num)
201 {
202 	res->cur += num;
203 	if (res->cur > res->peak)
204 		res->peak = res->cur;
205 }
206 
207 static void usage_free(struct snd_seq_usage *res, int num)
208 {
209 	res->cur -= num;
210 }
211 
212 /* initialise data structures */
213 int __init client_init_data(void)
214 {
215 	/* zap out the client table */
216 	memset(&clienttablock, 0, sizeof(clienttablock));
217 	memset(&clienttab, 0, sizeof(clienttab));
218 	return 0;
219 }
220 
221 
222 static struct snd_seq_client *seq_create_client1(int client_index, int poolsize)
223 {
224 	unsigned long flags;
225 	int c;
226 	struct snd_seq_client *client;
227 
228 	/* init client data */
229 	client = kzalloc(sizeof(*client), GFP_KERNEL);
230 	if (client == NULL)
231 		return NULL;
232 	client->pool = snd_seq_pool_new(poolsize);
233 	if (client->pool == NULL) {
234 		kfree(client);
235 		return NULL;
236 	}
237 	client->type = NO_CLIENT;
238 	snd_use_lock_init(&client->use_lock);
239 	rwlock_init(&client->ports_lock);
240 	mutex_init(&client->ports_mutex);
241 	INIT_LIST_HEAD(&client->ports_list_head);
242 
243 	/* find free slot in the client table */
244 	spin_lock_irqsave(&clients_lock, flags);
245 	if (client_index < 0) {
246 		for (c = SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN;
247 		     c < SNDRV_SEQ_MAX_CLIENTS;
248 		     c++) {
249 			if (clienttab[c] || clienttablock[c])
250 				continue;
251 			clienttab[client->number = c] = client;
252 			spin_unlock_irqrestore(&clients_lock, flags);
253 			return client;
254 		}
255 	} else {
256 		if (clienttab[client_index] == NULL && !clienttablock[client_index]) {
257 			clienttab[client->number = client_index] = client;
258 			spin_unlock_irqrestore(&clients_lock, flags);
259 			return client;
260 		}
261 	}
262 	spin_unlock_irqrestore(&clients_lock, flags);
263 	snd_seq_pool_delete(&client->pool);
264 	kfree(client);
265 	return NULL;	/* no free slot found or busy, return failure code */
266 }
267 
268 
269 static int seq_free_client1(struct snd_seq_client *client)
270 {
271 	unsigned long flags;
272 
273 	snd_assert(client != NULL, return -EINVAL);
274 	snd_seq_delete_all_ports(client);
275 	snd_seq_queue_client_leave(client->number);
276 	spin_lock_irqsave(&clients_lock, flags);
277 	clienttablock[client->number] = 1;
278 	clienttab[client->number] = NULL;
279 	spin_unlock_irqrestore(&clients_lock, flags);
280 	snd_use_lock_sync(&client->use_lock);
281 	snd_seq_queue_client_termination(client->number);
282 	if (client->pool)
283 		snd_seq_pool_delete(&client->pool);
284 	spin_lock_irqsave(&clients_lock, flags);
285 	clienttablock[client->number] = 0;
286 	spin_unlock_irqrestore(&clients_lock, flags);
287 	return 0;
288 }
289 
290 
291 static void seq_free_client(struct snd_seq_client * client)
292 {
293 	mutex_lock(&register_mutex);
294 	switch (client->type) {
295 	case NO_CLIENT:
296 		snd_printk(KERN_WARNING "Seq: Trying to free unused client %d\n",
297 			   client->number);
298 		break;
299 	case USER_CLIENT:
300 	case KERNEL_CLIENT:
301 		seq_free_client1(client);
302 		usage_free(&client_usage, 1);
303 		break;
304 
305 	default:
306 		snd_printk(KERN_ERR "Seq: Trying to free client %d with undefined type = %d\n",
307 			   client->number, client->type);
308 	}
309 	mutex_unlock(&register_mutex);
310 
311 	snd_seq_system_client_ev_client_exit(client->number);
312 }
313 
314 
315 
316 /* -------------------------------------------------------- */
317 
318 /* create a user client */
319 static int snd_seq_open(struct inode *inode, struct file *file)
320 {
321 	int c, mode;			/* client id */
322 	struct snd_seq_client *client;
323 	struct snd_seq_user_client *user;
324 
325 	if (mutex_lock_interruptible(&register_mutex))
326 		return -ERESTARTSYS;
327 	client = seq_create_client1(-1, SNDRV_SEQ_DEFAULT_EVENTS);
328 	if (client == NULL) {
329 		mutex_unlock(&register_mutex);
330 		return -ENOMEM;	/* failure code */
331 	}
332 
333 	mode = snd_seq_file_flags(file);
334 	if (mode & SNDRV_SEQ_LFLG_INPUT)
335 		client->accept_input = 1;
336 	if (mode & SNDRV_SEQ_LFLG_OUTPUT)
337 		client->accept_output = 1;
338 
339 	user = &client->data.user;
340 	user->fifo = NULL;
341 	user->fifo_pool_size = 0;
342 
343 	if (mode & SNDRV_SEQ_LFLG_INPUT) {
344 		user->fifo_pool_size = SNDRV_SEQ_DEFAULT_CLIENT_EVENTS;
345 		user->fifo = snd_seq_fifo_new(user->fifo_pool_size);
346 		if (user->fifo == NULL) {
347 			seq_free_client1(client);
348 			kfree(client);
349 			mutex_unlock(&register_mutex);
350 			return -ENOMEM;
351 		}
352 	}
353 
354 	usage_alloc(&client_usage, 1);
355 	client->type = USER_CLIENT;
356 	mutex_unlock(&register_mutex);
357 
358 	c = client->number;
359 	file->private_data = client;
360 
361 	/* fill client data */
362 	user->file = file;
363 	sprintf(client->name, "Client-%d", c);
364 
365 	/* make others aware this new client */
366 	snd_seq_system_client_ev_client_start(c);
367 
368 	return 0;
369 }
370 
371 /* delete a user client */
372 static int snd_seq_release(struct inode *inode, struct file *file)
373 {
374 	struct snd_seq_client *client = file->private_data;
375 
376 	if (client) {
377 		seq_free_client(client);
378 		if (client->data.user.fifo)
379 			snd_seq_fifo_delete(&client->data.user.fifo);
380 		kfree(client);
381 	}
382 
383 	return 0;
384 }
385 
386 
387 /* handle client read() */
388 /* possible error values:
389  *	-ENXIO	invalid client or file open mode
390  *	-ENOSPC	FIFO overflow (the flag is cleared after this error report)
391  *	-EINVAL	no enough user-space buffer to write the whole event
392  *	-EFAULT	seg. fault during copy to user space
393  */
394 static ssize_t snd_seq_read(struct file *file, char __user *buf, size_t count,
395 			    loff_t *offset)
396 {
397 	struct snd_seq_client *client = file->private_data;
398 	struct snd_seq_fifo *fifo;
399 	int err;
400 	long result = 0;
401 	struct snd_seq_event_cell *cell;
402 
403 	if (!(snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_INPUT))
404 		return -ENXIO;
405 
406 	if (!access_ok(VERIFY_WRITE, buf, count))
407 		return -EFAULT;
408 
409 	/* check client structures are in place */
410 	snd_assert(client != NULL, return -ENXIO);
411 
412 	if (!client->accept_input || (fifo = client->data.user.fifo) == NULL)
413 		return -ENXIO;
414 
415 	if (atomic_read(&fifo->overflow) > 0) {
416 		/* buffer overflow is detected */
417 		snd_seq_fifo_clear(fifo);
418 		/* return error code */
419 		return -ENOSPC;
420 	}
421 
422 	cell = NULL;
423 	err = 0;
424 	snd_seq_fifo_lock(fifo);
425 
426 	/* while data available in queue */
427 	while (count >= sizeof(struct snd_seq_event)) {
428 		int nonblock;
429 
430 		nonblock = (file->f_flags & O_NONBLOCK) || result > 0;
431 		if ((err = snd_seq_fifo_cell_out(fifo, &cell, nonblock)) < 0) {
432 			break;
433 		}
434 		if (snd_seq_ev_is_variable(&cell->event)) {
435 			struct snd_seq_event tmpev;
436 			tmpev = cell->event;
437 			tmpev.data.ext.len &= ~SNDRV_SEQ_EXT_MASK;
438 			if (copy_to_user(buf, &tmpev, sizeof(struct snd_seq_event))) {
439 				err = -EFAULT;
440 				break;
441 			}
442 			count -= sizeof(struct snd_seq_event);
443 			buf += sizeof(struct snd_seq_event);
444 			err = snd_seq_expand_var_event(&cell->event, count,
445 						       (char __force *)buf, 0,
446 						       sizeof(struct snd_seq_event));
447 			if (err < 0)
448 				break;
449 			result += err;
450 			count -= err;
451 			buf += err;
452 		} else {
453 			if (copy_to_user(buf, &cell->event, sizeof(struct snd_seq_event))) {
454 				err = -EFAULT;
455 				break;
456 			}
457 			count -= sizeof(struct snd_seq_event);
458 			buf += sizeof(struct snd_seq_event);
459 		}
460 		snd_seq_cell_free(cell);
461 		cell = NULL; /* to be sure */
462 		result += sizeof(struct snd_seq_event);
463 	}
464 
465 	if (err < 0) {
466 		if (cell)
467 			snd_seq_fifo_cell_putback(fifo, cell);
468 		if (err == -EAGAIN && result > 0)
469 			err = 0;
470 	}
471 	snd_seq_fifo_unlock(fifo);
472 
473 	return (err < 0) ? err : result;
474 }
475 
476 
477 /*
478  * check access permission to the port
479  */
480 static int check_port_perm(struct snd_seq_client_port *port, unsigned int flags)
481 {
482 	if ((port->capability & flags) != flags)
483 		return 0;
484 	return flags;
485 }
486 
487 /*
488  * check if the destination client is available, and return the pointer
489  * if filter is non-zero, client filter bitmap is tested.
490  */
491 static struct snd_seq_client *get_event_dest_client(struct snd_seq_event *event,
492 						    int filter)
493 {
494 	struct snd_seq_client *dest;
495 
496 	dest = snd_seq_client_use_ptr(event->dest.client);
497 	if (dest == NULL)
498 		return NULL;
499 	if (! dest->accept_input)
500 		goto __not_avail;
501 	if ((dest->filter & SNDRV_SEQ_FILTER_USE_EVENT) &&
502 	    ! test_bit(event->type, dest->event_filter))
503 		goto __not_avail;
504 	if (filter && !(dest->filter & filter))
505 		goto __not_avail;
506 
507 	return dest; /* ok - accessible */
508 __not_avail:
509 	snd_seq_client_unlock(dest);
510 	return NULL;
511 }
512 
513 
514 /*
515  * Return the error event.
516  *
517  * If the receiver client is a user client, the original event is
518  * encapsulated in SNDRV_SEQ_EVENT_BOUNCE as variable length event.  If
519  * the original event is also variable length, the external data is
520  * copied after the event record.
521  * If the receiver client is a kernel client, the original event is
522  * quoted in SNDRV_SEQ_EVENT_KERNEL_ERROR, since this requires no extra
523  * kmalloc.
524  */
525 static int bounce_error_event(struct snd_seq_client *client,
526 			      struct snd_seq_event *event,
527 			      int err, int atomic, int hop)
528 {
529 	struct snd_seq_event bounce_ev;
530 	int result;
531 
532 	if (client == NULL ||
533 	    ! (client->filter & SNDRV_SEQ_FILTER_BOUNCE) ||
534 	    ! client->accept_input)
535 		return 0; /* ignored */
536 
537 	/* set up quoted error */
538 	memset(&bounce_ev, 0, sizeof(bounce_ev));
539 	bounce_ev.type = SNDRV_SEQ_EVENT_KERNEL_ERROR;
540 	bounce_ev.flags = SNDRV_SEQ_EVENT_LENGTH_FIXED;
541 	bounce_ev.queue = SNDRV_SEQ_QUEUE_DIRECT;
542 	bounce_ev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
543 	bounce_ev.source.port = SNDRV_SEQ_PORT_SYSTEM_ANNOUNCE;
544 	bounce_ev.dest.client = client->number;
545 	bounce_ev.dest.port = event->source.port;
546 	bounce_ev.data.quote.origin = event->dest;
547 	bounce_ev.data.quote.event = event;
548 	bounce_ev.data.quote.value = -err; /* use positive value */
549 	result = snd_seq_deliver_single_event(NULL, &bounce_ev, 0, atomic, hop + 1);
550 	if (result < 0) {
551 		client->event_lost++;
552 		return result;
553 	}
554 
555 	return result;
556 }
557 
558 
559 /*
560  * rewrite the time-stamp of the event record with the curren time
561  * of the given queue.
562  * return non-zero if updated.
563  */
564 static int update_timestamp_of_queue(struct snd_seq_event *event,
565 				     int queue, int real_time)
566 {
567 	struct snd_seq_queue *q;
568 
569 	q = queueptr(queue);
570 	if (! q)
571 		return 0;
572 	event->queue = queue;
573 	event->flags &= ~SNDRV_SEQ_TIME_STAMP_MASK;
574 	if (real_time) {
575 		event->time.time = snd_seq_timer_get_cur_time(q->timer);
576 		event->flags |= SNDRV_SEQ_TIME_STAMP_REAL;
577 	} else {
578 		event->time.tick = snd_seq_timer_get_cur_tick(q->timer);
579 		event->flags |= SNDRV_SEQ_TIME_STAMP_TICK;
580 	}
581 	queuefree(q);
582 	return 1;
583 }
584 
585 
586 /*
587  * deliver an event to the specified destination.
588  * if filter is non-zero, client filter bitmap is tested.
589  *
590  *  RETURN VALUE: 0 : if succeeded
591  *		 <0 : error
592  */
593 static int snd_seq_deliver_single_event(struct snd_seq_client *client,
594 					struct snd_seq_event *event,
595 					int filter, int atomic, int hop)
596 {
597 	struct snd_seq_client *dest = NULL;
598 	struct snd_seq_client_port *dest_port = NULL;
599 	int result = -ENOENT;
600 	int direct;
601 
602 	direct = snd_seq_ev_is_direct(event);
603 
604 	dest = get_event_dest_client(event, filter);
605 	if (dest == NULL)
606 		goto __skip;
607 	dest_port = snd_seq_port_use_ptr(dest, event->dest.port);
608 	if (dest_port == NULL)
609 		goto __skip;
610 
611 	/* check permission */
612 	if (! check_port_perm(dest_port, SNDRV_SEQ_PORT_CAP_WRITE)) {
613 		result = -EPERM;
614 		goto __skip;
615 	}
616 
617 	if (dest_port->timestamping)
618 		update_timestamp_of_queue(event, dest_port->time_queue,
619 					  dest_port->time_real);
620 
621 	switch (dest->type) {
622 	case USER_CLIENT:
623 		if (dest->data.user.fifo)
624 			result = snd_seq_fifo_event_in(dest->data.user.fifo, event);
625 		break;
626 
627 	case KERNEL_CLIENT:
628 		if (dest_port->event_input == NULL)
629 			break;
630 		result = dest_port->event_input(event, direct,
631 						dest_port->private_data,
632 						atomic, hop);
633 		break;
634 	default:
635 		break;
636 	}
637 
638   __skip:
639 	if (dest_port)
640 		snd_seq_port_unlock(dest_port);
641 	if (dest)
642 		snd_seq_client_unlock(dest);
643 
644 	if (result < 0 && !direct) {
645 		result = bounce_error_event(client, event, result, atomic, hop);
646 	}
647 	return result;
648 }
649 
650 
651 /*
652  * send the event to all subscribers:
653  */
654 static int deliver_to_subscribers(struct snd_seq_client *client,
655 				  struct snd_seq_event *event,
656 				  int atomic, int hop)
657 {
658 	struct snd_seq_subscribers *subs;
659 	int err = 0, num_ev = 0;
660 	struct snd_seq_event event_saved;
661 	struct snd_seq_client_port *src_port;
662 	struct snd_seq_port_subs_info *grp;
663 
664 	src_port = snd_seq_port_use_ptr(client, event->source.port);
665 	if (src_port == NULL)
666 		return -EINVAL; /* invalid source port */
667 	/* save original event record */
668 	event_saved = *event;
669 	grp = &src_port->c_src;
670 
671 	/* lock list */
672 	if (atomic)
673 		read_lock(&grp->list_lock);
674 	else
675 		down_read(&grp->list_mutex);
676 	list_for_each_entry(subs, &grp->list_head, src_list) {
677 		event->dest = subs->info.dest;
678 		if (subs->info.flags & SNDRV_SEQ_PORT_SUBS_TIMESTAMP)
679 			/* convert time according to flag with subscription */
680 			update_timestamp_of_queue(event, subs->info.queue,
681 						  subs->info.flags & SNDRV_SEQ_PORT_SUBS_TIME_REAL);
682 		err = snd_seq_deliver_single_event(client, event,
683 						   0, atomic, hop);
684 		if (err < 0)
685 			break;
686 		num_ev++;
687 		/* restore original event record */
688 		*event = event_saved;
689 	}
690 	if (atomic)
691 		read_unlock(&grp->list_lock);
692 	else
693 		up_read(&grp->list_mutex);
694 	*event = event_saved; /* restore */
695 	snd_seq_port_unlock(src_port);
696 	return (err < 0) ? err : num_ev;
697 }
698 
699 
700 #ifdef SUPPORT_BROADCAST
701 /*
702  * broadcast to all ports:
703  */
704 static int port_broadcast_event(struct snd_seq_client *client,
705 				struct snd_seq_event *event,
706 				int atomic, int hop)
707 {
708 	int num_ev = 0, err = 0;
709 	struct snd_seq_client *dest_client;
710 	struct snd_seq_client_port *port;
711 
712 	dest_client = get_event_dest_client(event, SNDRV_SEQ_FILTER_BROADCAST);
713 	if (dest_client == NULL)
714 		return 0; /* no matching destination */
715 
716 	read_lock(&dest_client->ports_lock);
717 	list_for_each_entry(port, &dest_client->ports_list_head, list) {
718 		event->dest.port = port->addr.port;
719 		/* pass NULL as source client to avoid error bounce */
720 		err = snd_seq_deliver_single_event(NULL, event,
721 						   SNDRV_SEQ_FILTER_BROADCAST,
722 						   atomic, hop);
723 		if (err < 0)
724 			break;
725 		num_ev++;
726 	}
727 	read_unlock(&dest_client->ports_lock);
728 	snd_seq_client_unlock(dest_client);
729 	event->dest.port = SNDRV_SEQ_ADDRESS_BROADCAST; /* restore */
730 	return (err < 0) ? err : num_ev;
731 }
732 
733 /*
734  * send the event to all clients:
735  * if destination port is also ADDRESS_BROADCAST, deliver to all ports.
736  */
737 static int broadcast_event(struct snd_seq_client *client,
738 			   struct snd_seq_event *event, int atomic, int hop)
739 {
740 	int err = 0, num_ev = 0;
741 	int dest;
742 	struct snd_seq_addr addr;
743 
744 	addr = event->dest; /* save */
745 
746 	for (dest = 0; dest < SNDRV_SEQ_MAX_CLIENTS; dest++) {
747 		/* don't send to itself */
748 		if (dest == client->number)
749 			continue;
750 		event->dest.client = dest;
751 		event->dest.port = addr.port;
752 		if (addr.port == SNDRV_SEQ_ADDRESS_BROADCAST)
753 			err = port_broadcast_event(client, event, atomic, hop);
754 		else
755 			/* pass NULL as source client to avoid error bounce */
756 			err = snd_seq_deliver_single_event(NULL, event,
757 							   SNDRV_SEQ_FILTER_BROADCAST,
758 							   atomic, hop);
759 		if (err < 0)
760 			break;
761 		num_ev += err;
762 	}
763 	event->dest = addr; /* restore */
764 	return (err < 0) ? err : num_ev;
765 }
766 
767 
768 /* multicast - not supported yet */
769 static int multicast_event(struct snd_seq_client *client, struct snd_seq_event *event,
770 			   int atomic, int hop)
771 {
772 	snd_printd("seq: multicast not supported yet.\n");
773 	return 0; /* ignored */
774 }
775 #endif /* SUPPORT_BROADCAST */
776 
777 
778 /* deliver an event to the destination port(s).
779  * if the event is to subscribers or broadcast, the event is dispatched
780  * to multiple targets.
781  *
782  * RETURN VALUE: n > 0  : the number of delivered events.
783  *               n == 0 : the event was not passed to any client.
784  *               n < 0  : error - event was not processed.
785  */
786 static int snd_seq_deliver_event(struct snd_seq_client *client, struct snd_seq_event *event,
787 				 int atomic, int hop)
788 {
789 	int result;
790 
791 	hop++;
792 	if (hop >= SNDRV_SEQ_MAX_HOPS) {
793 		snd_printd("too long delivery path (%d:%d->%d:%d)\n",
794 			   event->source.client, event->source.port,
795 			   event->dest.client, event->dest.port);
796 		return -EMLINK;
797 	}
798 
799 	if (event->queue == SNDRV_SEQ_ADDRESS_SUBSCRIBERS ||
800 	    event->dest.client == SNDRV_SEQ_ADDRESS_SUBSCRIBERS)
801 		result = deliver_to_subscribers(client, event, atomic, hop);
802 #ifdef SUPPORT_BROADCAST
803 	else if (event->queue == SNDRV_SEQ_ADDRESS_BROADCAST ||
804 		 event->dest.client == SNDRV_SEQ_ADDRESS_BROADCAST)
805 		result = broadcast_event(client, event, atomic, hop);
806 	else if (event->dest.client >= SNDRV_SEQ_MAX_CLIENTS)
807 		result = multicast_event(client, event, atomic, hop);
808 	else if (event->dest.port == SNDRV_SEQ_ADDRESS_BROADCAST)
809 		result = port_broadcast_event(client, event, atomic, hop);
810 #endif
811 	else
812 		result = snd_seq_deliver_single_event(client, event, 0, atomic, hop);
813 
814 	return result;
815 }
816 
817 /*
818  * dispatch an event cell:
819  * This function is called only from queue check routines in timer
820  * interrupts or after enqueued.
821  * The event cell shall be released or re-queued in this function.
822  *
823  * RETURN VALUE: n > 0  : the number of delivered events.
824  *		 n == 0 : the event was not passed to any client.
825  *		 n < 0  : error - event was not processed.
826  */
827 int snd_seq_dispatch_event(struct snd_seq_event_cell *cell, int atomic, int hop)
828 {
829 	struct snd_seq_client *client;
830 	int result;
831 
832 	snd_assert(cell != NULL, return -EINVAL);
833 
834 	client = snd_seq_client_use_ptr(cell->event.source.client);
835 	if (client == NULL) {
836 		snd_seq_cell_free(cell); /* release this cell */
837 		return -EINVAL;
838 	}
839 
840 	if (cell->event.type == SNDRV_SEQ_EVENT_NOTE) {
841 		/* NOTE event:
842 		 * the event cell is re-used as a NOTE-OFF event and
843 		 * enqueued again.
844 		 */
845 		struct snd_seq_event tmpev, *ev;
846 
847 		/* reserve this event to enqueue note-off later */
848 		tmpev = cell->event;
849 		tmpev.type = SNDRV_SEQ_EVENT_NOTEON;
850 		result = snd_seq_deliver_event(client, &tmpev, atomic, hop);
851 
852 		/*
853 		 * This was originally a note event.  We now re-use the
854 		 * cell for the note-off event.
855 		 */
856 
857 		ev = &cell->event;
858 		ev->type = SNDRV_SEQ_EVENT_NOTEOFF;
859 		ev->flags |= SNDRV_SEQ_PRIORITY_HIGH;
860 
861 		/* add the duration time */
862 		switch (ev->flags & SNDRV_SEQ_TIME_STAMP_MASK) {
863 		case SNDRV_SEQ_TIME_STAMP_TICK:
864 			ev->time.tick += ev->data.note.duration;
865 			break;
866 		case SNDRV_SEQ_TIME_STAMP_REAL:
867 			/* unit for duration is ms */
868 			ev->time.time.tv_nsec += 1000000 * (ev->data.note.duration % 1000);
869 			ev->time.time.tv_sec += ev->data.note.duration / 1000 +
870 						ev->time.time.tv_nsec / 1000000000;
871 			ev->time.time.tv_nsec %= 1000000000;
872 			break;
873 		}
874 		ev->data.note.velocity = ev->data.note.off_velocity;
875 
876 		/* Now queue this cell as the note off event */
877 		if (snd_seq_enqueue_event(cell, atomic, hop) < 0)
878 			snd_seq_cell_free(cell); /* release this cell */
879 
880 	} else {
881 		/* Normal events:
882 		 * event cell is freed after processing the event
883 		 */
884 
885 		result = snd_seq_deliver_event(client, &cell->event, atomic, hop);
886 		snd_seq_cell_free(cell);
887 	}
888 
889 	snd_seq_client_unlock(client);
890 	return result;
891 }
892 
893 
894 /* Allocate a cell from client pool and enqueue it to queue:
895  * if pool is empty and blocking is TRUE, sleep until a new cell is
896  * available.
897  */
898 static int snd_seq_client_enqueue_event(struct snd_seq_client *client,
899 					struct snd_seq_event *event,
900 					struct file *file, int blocking,
901 					int atomic, int hop)
902 {
903 	struct snd_seq_event_cell *cell;
904 	int err;
905 
906 	/* special queue values - force direct passing */
907 	if (event->queue == SNDRV_SEQ_ADDRESS_SUBSCRIBERS) {
908 		event->dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
909 		event->queue = SNDRV_SEQ_QUEUE_DIRECT;
910 	} else
911 #ifdef SUPPORT_BROADCAST
912 		if (event->queue == SNDRV_SEQ_ADDRESS_BROADCAST) {
913 			event->dest.client = SNDRV_SEQ_ADDRESS_BROADCAST;
914 			event->queue = SNDRV_SEQ_QUEUE_DIRECT;
915 		}
916 #endif
917 	if (event->dest.client == SNDRV_SEQ_ADDRESS_SUBSCRIBERS) {
918 		/* check presence of source port */
919 		struct snd_seq_client_port *src_port = snd_seq_port_use_ptr(client, event->source.port);
920 		if (src_port == NULL)
921 			return -EINVAL;
922 		snd_seq_port_unlock(src_port);
923 	}
924 
925 	/* direct event processing without enqueued */
926 	if (snd_seq_ev_is_direct(event)) {
927 		if (event->type == SNDRV_SEQ_EVENT_NOTE)
928 			return -EINVAL; /* this event must be enqueued! */
929 		return snd_seq_deliver_event(client, event, atomic, hop);
930 	}
931 
932 	/* Not direct, normal queuing */
933 	if (snd_seq_queue_is_used(event->queue, client->number) <= 0)
934 		return -EINVAL;  /* invalid queue */
935 	if (! snd_seq_write_pool_allocated(client))
936 		return -ENXIO; /* queue is not allocated */
937 
938 	/* allocate an event cell */
939 	err = snd_seq_event_dup(client->pool, event, &cell, !blocking || atomic, file);
940 	if (err < 0)
941 		return err;
942 
943 	/* we got a cell. enqueue it. */
944 	if ((err = snd_seq_enqueue_event(cell, atomic, hop)) < 0) {
945 		snd_seq_cell_free(cell);
946 		return err;
947 	}
948 
949 	return 0;
950 }
951 
952 
953 /*
954  * check validity of event type and data length.
955  * return non-zero if invalid.
956  */
957 static int check_event_type_and_length(struct snd_seq_event *ev)
958 {
959 	switch (snd_seq_ev_length_type(ev)) {
960 	case SNDRV_SEQ_EVENT_LENGTH_FIXED:
961 		if (snd_seq_ev_is_variable_type(ev))
962 			return -EINVAL;
963 		break;
964 	case SNDRV_SEQ_EVENT_LENGTH_VARIABLE:
965 		if (! snd_seq_ev_is_variable_type(ev) ||
966 		    (ev->data.ext.len & ~SNDRV_SEQ_EXT_MASK) >= SNDRV_SEQ_MAX_EVENT_LEN)
967 			return -EINVAL;
968 		break;
969 	case SNDRV_SEQ_EVENT_LENGTH_VARUSR:
970 		if (! snd_seq_ev_is_instr_type(ev) ||
971 		    ! snd_seq_ev_is_direct(ev))
972 			return -EINVAL;
973 		break;
974 	}
975 	return 0;
976 }
977 
978 
979 /* handle write() */
980 /* possible error values:
981  *	-ENXIO	invalid client or file open mode
982  *	-ENOMEM	malloc failed
983  *	-EFAULT	seg. fault during copy from user space
984  *	-EINVAL	invalid event
985  *	-EAGAIN	no space in output pool
986  *	-EINTR	interrupts while sleep
987  *	-EMLINK	too many hops
988  *	others	depends on return value from driver callback
989  */
990 static ssize_t snd_seq_write(struct file *file, const char __user *buf,
991 			     size_t count, loff_t *offset)
992 {
993 	struct snd_seq_client *client = file->private_data;
994 	int written = 0, len;
995 	int err = -EINVAL;
996 	struct snd_seq_event event;
997 
998 	if (!(snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_OUTPUT))
999 		return -ENXIO;
1000 
1001 	/* check client structures are in place */
1002 	snd_assert(client != NULL, return -ENXIO);
1003 
1004 	if (!client->accept_output || client->pool == NULL)
1005 		return -ENXIO;
1006 
1007 	/* allocate the pool now if the pool is not allocated yet */
1008 	if (client->pool->size > 0 && !snd_seq_write_pool_allocated(client)) {
1009 		if (snd_seq_pool_init(client->pool) < 0)
1010 			return -ENOMEM;
1011 	}
1012 
1013 	/* only process whole events */
1014 	while (count >= sizeof(struct snd_seq_event)) {
1015 		/* Read in the event header from the user */
1016 		len = sizeof(event);
1017 		if (copy_from_user(&event, buf, len)) {
1018 			err = -EFAULT;
1019 			break;
1020 		}
1021 		event.source.client = client->number;	/* fill in client number */
1022 		/* Check for extension data length */
1023 		if (check_event_type_and_length(&event)) {
1024 			err = -EINVAL;
1025 			break;
1026 		}
1027 
1028 		/* check for special events */
1029 		if (event.type == SNDRV_SEQ_EVENT_NONE)
1030 			goto __skip_event;
1031 		else if (snd_seq_ev_is_reserved(&event)) {
1032 			err = -EINVAL;
1033 			break;
1034 		}
1035 
1036 		if (snd_seq_ev_is_variable(&event)) {
1037 			int extlen = event.data.ext.len & ~SNDRV_SEQ_EXT_MASK;
1038 			if ((size_t)(extlen + len) > count) {
1039 				/* back out, will get an error this time or next */
1040 				err = -EINVAL;
1041 				break;
1042 			}
1043 			/* set user space pointer */
1044 			event.data.ext.len = extlen | SNDRV_SEQ_EXT_USRPTR;
1045 			event.data.ext.ptr = (char __force *)buf
1046 						+ sizeof(struct snd_seq_event);
1047 			len += extlen; /* increment data length */
1048 		} else {
1049 #ifdef CONFIG_COMPAT
1050 			if (client->convert32 && snd_seq_ev_is_varusr(&event)) {
1051 				void *ptr = compat_ptr(event.data.raw32.d[1]);
1052 				event.data.ext.ptr = ptr;
1053 			}
1054 #endif
1055 		}
1056 
1057 		/* ok, enqueue it */
1058 		err = snd_seq_client_enqueue_event(client, &event, file,
1059 						   !(file->f_flags & O_NONBLOCK),
1060 						   0, 0);
1061 		if (err < 0)
1062 			break;
1063 
1064 	__skip_event:
1065 		/* Update pointers and counts */
1066 		count -= len;
1067 		buf += len;
1068 		written += len;
1069 	}
1070 
1071 	return written ? written : err;
1072 }
1073 
1074 
1075 /*
1076  * handle polling
1077  */
1078 static unsigned int snd_seq_poll(struct file *file, poll_table * wait)
1079 {
1080 	struct snd_seq_client *client = file->private_data;
1081 	unsigned int mask = 0;
1082 
1083 	/* check client structures are in place */
1084 	snd_assert(client != NULL, return -ENXIO);
1085 
1086 	if ((snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_INPUT) &&
1087 	    client->data.user.fifo) {
1088 
1089 		/* check if data is available in the outqueue */
1090 		if (snd_seq_fifo_poll_wait(client->data.user.fifo, file, wait))
1091 			mask |= POLLIN | POLLRDNORM;
1092 	}
1093 
1094 	if (snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_OUTPUT) {
1095 
1096 		/* check if data is available in the pool */
1097 		if (!snd_seq_write_pool_allocated(client) ||
1098 		    snd_seq_pool_poll_wait(client->pool, file, wait))
1099 			mask |= POLLOUT | POLLWRNORM;
1100 	}
1101 
1102 	return mask;
1103 }
1104 
1105 
1106 /*-----------------------------------------------------*/
1107 
1108 
1109 /* SYSTEM_INFO ioctl() */
1110 static int snd_seq_ioctl_system_info(struct snd_seq_client *client, void __user *arg)
1111 {
1112 	struct snd_seq_system_info info;
1113 
1114 	memset(&info, 0, sizeof(info));
1115 	/* fill the info fields */
1116 	info.queues = SNDRV_SEQ_MAX_QUEUES;
1117 	info.clients = SNDRV_SEQ_MAX_CLIENTS;
1118 	info.ports = 256;	/* fixed limit */
1119 	info.channels = 256;	/* fixed limit */
1120 	info.cur_clients = client_usage.cur;
1121 	info.cur_queues = snd_seq_queue_get_cur_queues();
1122 
1123 	if (copy_to_user(arg, &info, sizeof(info)))
1124 		return -EFAULT;
1125 	return 0;
1126 }
1127 
1128 
1129 /* RUNNING_MODE ioctl() */
1130 static int snd_seq_ioctl_running_mode(struct snd_seq_client *client, void __user *arg)
1131 {
1132 	struct snd_seq_running_info info;
1133 	struct snd_seq_client *cptr;
1134 	int err = 0;
1135 
1136 	if (copy_from_user(&info, arg, sizeof(info)))
1137 		return -EFAULT;
1138 
1139 	/* requested client number */
1140 	cptr = snd_seq_client_use_ptr(info.client);
1141 	if (cptr == NULL)
1142 		return -ENOENT;		/* don't change !!! */
1143 
1144 #ifdef SNDRV_BIG_ENDIAN
1145 	if (! info.big_endian) {
1146 		err = -EINVAL;
1147 		goto __err;
1148 	}
1149 #else
1150 	if (info.big_endian) {
1151 		err = -EINVAL;
1152 		goto __err;
1153 	}
1154 
1155 #endif
1156 	if (info.cpu_mode > sizeof(long)) {
1157 		err = -EINVAL;
1158 		goto __err;
1159 	}
1160 	cptr->convert32 = (info.cpu_mode < sizeof(long));
1161  __err:
1162 	snd_seq_client_unlock(cptr);
1163 	return err;
1164 }
1165 
1166 /* CLIENT_INFO ioctl() */
1167 static void get_client_info(struct snd_seq_client *cptr,
1168 			    struct snd_seq_client_info *info)
1169 {
1170 	info->client = cptr->number;
1171 
1172 	/* fill the info fields */
1173 	info->type = cptr->type;
1174 	strcpy(info->name, cptr->name);
1175 	info->filter = cptr->filter;
1176 	info->event_lost = cptr->event_lost;
1177 	memcpy(info->event_filter, cptr->event_filter, 32);
1178 	info->num_ports = cptr->num_ports;
1179 	memset(info->reserved, 0, sizeof(info->reserved));
1180 }
1181 
1182 static int snd_seq_ioctl_get_client_info(struct snd_seq_client *client,
1183 					 void __user *arg)
1184 {
1185 	struct snd_seq_client *cptr;
1186 	struct snd_seq_client_info client_info;
1187 
1188 	if (copy_from_user(&client_info, arg, sizeof(client_info)))
1189 		return -EFAULT;
1190 
1191 	/* requested client number */
1192 	cptr = snd_seq_client_use_ptr(client_info.client);
1193 	if (cptr == NULL)
1194 		return -ENOENT;		/* don't change !!! */
1195 
1196 	get_client_info(cptr, &client_info);
1197 	snd_seq_client_unlock(cptr);
1198 
1199 	if (copy_to_user(arg, &client_info, sizeof(client_info)))
1200 		return -EFAULT;
1201 	return 0;
1202 }
1203 
1204 
1205 /* CLIENT_INFO ioctl() */
1206 static int snd_seq_ioctl_set_client_info(struct snd_seq_client *client,
1207 					 void __user *arg)
1208 {
1209 	struct snd_seq_client_info client_info;
1210 
1211 	if (copy_from_user(&client_info, arg, sizeof(client_info)))
1212 		return -EFAULT;
1213 
1214 	/* it is not allowed to set the info fields for an another client */
1215 	if (client->number != client_info.client)
1216 		return -EPERM;
1217 	/* also client type must be set now */
1218 	if (client->type != client_info.type)
1219 		return -EINVAL;
1220 
1221 	/* fill the info fields */
1222 	if (client_info.name[0])
1223 		strlcpy(client->name, client_info.name, sizeof(client->name));
1224 
1225 	client->filter = client_info.filter;
1226 	client->event_lost = client_info.event_lost;
1227 	memcpy(client->event_filter, client_info.event_filter, 32);
1228 
1229 	return 0;
1230 }
1231 
1232 
1233 /*
1234  * CREATE PORT ioctl()
1235  */
1236 static int snd_seq_ioctl_create_port(struct snd_seq_client *client,
1237 				     void __user *arg)
1238 {
1239 	struct snd_seq_client_port *port;
1240 	struct snd_seq_port_info info;
1241 	struct snd_seq_port_callback *callback;
1242 
1243 	if (copy_from_user(&info, arg, sizeof(info)))
1244 		return -EFAULT;
1245 
1246 	/* it is not allowed to create the port for an another client */
1247 	if (info.addr.client != client->number)
1248 		return -EPERM;
1249 
1250 	port = snd_seq_create_port(client, (info.flags & SNDRV_SEQ_PORT_FLG_GIVEN_PORT) ? info.addr.port : -1);
1251 	if (port == NULL)
1252 		return -ENOMEM;
1253 
1254 	if (client->type == USER_CLIENT && info.kernel) {
1255 		snd_seq_delete_port(client, port->addr.port);
1256 		return -EINVAL;
1257 	}
1258 	if (client->type == KERNEL_CLIENT) {
1259 		if ((callback = info.kernel) != NULL) {
1260 			if (callback->owner)
1261 				port->owner = callback->owner;
1262 			port->private_data = callback->private_data;
1263 			port->private_free = callback->private_free;
1264 			port->callback_all = callback->callback_all;
1265 			port->event_input = callback->event_input;
1266 			port->c_src.open = callback->subscribe;
1267 			port->c_src.close = callback->unsubscribe;
1268 			port->c_dest.open = callback->use;
1269 			port->c_dest.close = callback->unuse;
1270 		}
1271 	}
1272 
1273 	info.addr = port->addr;
1274 
1275 	snd_seq_set_port_info(port, &info);
1276 	snd_seq_system_client_ev_port_start(port->addr.client, port->addr.port);
1277 
1278 	if (copy_to_user(arg, &info, sizeof(info)))
1279 		return -EFAULT;
1280 
1281 	return 0;
1282 }
1283 
1284 /*
1285  * DELETE PORT ioctl()
1286  */
1287 static int snd_seq_ioctl_delete_port(struct snd_seq_client *client,
1288 				     void __user *arg)
1289 {
1290 	struct snd_seq_port_info info;
1291 	int err;
1292 
1293 	/* set passed parameters */
1294 	if (copy_from_user(&info, arg, sizeof(info)))
1295 		return -EFAULT;
1296 
1297 	/* it is not allowed to remove the port for an another client */
1298 	if (info.addr.client != client->number)
1299 		return -EPERM;
1300 
1301 	err = snd_seq_delete_port(client, info.addr.port);
1302 	if (err >= 0)
1303 		snd_seq_system_client_ev_port_exit(client->number, info.addr.port);
1304 	return err;
1305 }
1306 
1307 
1308 /*
1309  * GET_PORT_INFO ioctl() (on any client)
1310  */
1311 static int snd_seq_ioctl_get_port_info(struct snd_seq_client *client,
1312 				       void __user *arg)
1313 {
1314 	struct snd_seq_client *cptr;
1315 	struct snd_seq_client_port *port;
1316 	struct snd_seq_port_info info;
1317 
1318 	if (copy_from_user(&info, arg, sizeof(info)))
1319 		return -EFAULT;
1320 	cptr = snd_seq_client_use_ptr(info.addr.client);
1321 	if (cptr == NULL)
1322 		return -ENXIO;
1323 
1324 	port = snd_seq_port_use_ptr(cptr, info.addr.port);
1325 	if (port == NULL) {
1326 		snd_seq_client_unlock(cptr);
1327 		return -ENOENT;			/* don't change */
1328 	}
1329 
1330 	/* get port info */
1331 	snd_seq_get_port_info(port, &info);
1332 	snd_seq_port_unlock(port);
1333 	snd_seq_client_unlock(cptr);
1334 
1335 	if (copy_to_user(arg, &info, sizeof(info)))
1336 		return -EFAULT;
1337 	return 0;
1338 }
1339 
1340 
1341 /*
1342  * SET_PORT_INFO ioctl() (only ports on this/own client)
1343  */
1344 static int snd_seq_ioctl_set_port_info(struct snd_seq_client *client,
1345 				       void __user *arg)
1346 {
1347 	struct snd_seq_client_port *port;
1348 	struct snd_seq_port_info info;
1349 
1350 	if (copy_from_user(&info, arg, sizeof(info)))
1351 		return -EFAULT;
1352 
1353 	if (info.addr.client != client->number) /* only set our own ports ! */
1354 		return -EPERM;
1355 	port = snd_seq_port_use_ptr(client, info.addr.port);
1356 	if (port) {
1357 		snd_seq_set_port_info(port, &info);
1358 		snd_seq_port_unlock(port);
1359 	}
1360 	return 0;
1361 }
1362 
1363 
1364 /*
1365  * port subscription (connection)
1366  */
1367 #define PERM_RD		(SNDRV_SEQ_PORT_CAP_READ|SNDRV_SEQ_PORT_CAP_SUBS_READ)
1368 #define PERM_WR		(SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_SUBS_WRITE)
1369 
1370 static int check_subscription_permission(struct snd_seq_client *client,
1371 					 struct snd_seq_client_port *sport,
1372 					 struct snd_seq_client_port *dport,
1373 					 struct snd_seq_port_subscribe *subs)
1374 {
1375 	if (client->number != subs->sender.client &&
1376 	    client->number != subs->dest.client) {
1377 		/* connection by third client - check export permission */
1378 		if (check_port_perm(sport, SNDRV_SEQ_PORT_CAP_NO_EXPORT))
1379 			return -EPERM;
1380 		if (check_port_perm(dport, SNDRV_SEQ_PORT_CAP_NO_EXPORT))
1381 			return -EPERM;
1382 	}
1383 
1384 	/* check read permission */
1385 	/* if sender or receiver is the subscribing client itself,
1386 	 * no permission check is necessary
1387 	 */
1388 	if (client->number != subs->sender.client) {
1389 		if (! check_port_perm(sport, PERM_RD))
1390 			return -EPERM;
1391 	}
1392 	/* check write permission */
1393 	if (client->number != subs->dest.client) {
1394 		if (! check_port_perm(dport, PERM_WR))
1395 			return -EPERM;
1396 	}
1397 	return 0;
1398 }
1399 
1400 /*
1401  * send an subscription notify event to user client:
1402  * client must be user client.
1403  */
1404 int snd_seq_client_notify_subscription(int client, int port,
1405 				       struct snd_seq_port_subscribe *info,
1406 				       int evtype)
1407 {
1408 	struct snd_seq_event event;
1409 
1410 	memset(&event, 0, sizeof(event));
1411 	event.type = evtype;
1412 	event.data.connect.dest = info->dest;
1413 	event.data.connect.sender = info->sender;
1414 
1415 	return snd_seq_system_notify(client, port, &event);  /* non-atomic */
1416 }
1417 
1418 
1419 /*
1420  * add to port's subscription list IOCTL interface
1421  */
1422 static int snd_seq_ioctl_subscribe_port(struct snd_seq_client *client,
1423 					void __user *arg)
1424 {
1425 	int result = -EINVAL;
1426 	struct snd_seq_client *receiver = NULL, *sender = NULL;
1427 	struct snd_seq_client_port *sport = NULL, *dport = NULL;
1428 	struct snd_seq_port_subscribe subs;
1429 
1430 	if (copy_from_user(&subs, arg, sizeof(subs)))
1431 		return -EFAULT;
1432 
1433 	if ((receiver = snd_seq_client_use_ptr(subs.dest.client)) == NULL)
1434 		goto __end;
1435 	if ((sender = snd_seq_client_use_ptr(subs.sender.client)) == NULL)
1436 		goto __end;
1437 	if ((sport = snd_seq_port_use_ptr(sender, subs.sender.port)) == NULL)
1438 		goto __end;
1439 	if ((dport = snd_seq_port_use_ptr(receiver, subs.dest.port)) == NULL)
1440 		goto __end;
1441 
1442 	result = check_subscription_permission(client, sport, dport, &subs);
1443 	if (result < 0)
1444 		goto __end;
1445 
1446 	/* connect them */
1447 	result = snd_seq_port_connect(client, sender, sport, receiver, dport, &subs);
1448 	if (! result) /* broadcast announce */
1449 		snd_seq_client_notify_subscription(SNDRV_SEQ_ADDRESS_SUBSCRIBERS, 0,
1450 						   &subs, SNDRV_SEQ_EVENT_PORT_SUBSCRIBED);
1451       __end:
1452       	if (sport)
1453 		snd_seq_port_unlock(sport);
1454 	if (dport)
1455 		snd_seq_port_unlock(dport);
1456 	if (sender)
1457 		snd_seq_client_unlock(sender);
1458 	if (receiver)
1459 		snd_seq_client_unlock(receiver);
1460 	return result;
1461 }
1462 
1463 
1464 /*
1465  * remove from port's subscription list
1466  */
1467 static int snd_seq_ioctl_unsubscribe_port(struct snd_seq_client *client,
1468 					  void __user *arg)
1469 {
1470 	int result = -ENXIO;
1471 	struct snd_seq_client *receiver = NULL, *sender = NULL;
1472 	struct snd_seq_client_port *sport = NULL, *dport = NULL;
1473 	struct snd_seq_port_subscribe subs;
1474 
1475 	if (copy_from_user(&subs, arg, sizeof(subs)))
1476 		return -EFAULT;
1477 
1478 	if ((receiver = snd_seq_client_use_ptr(subs.dest.client)) == NULL)
1479 		goto __end;
1480 	if ((sender = snd_seq_client_use_ptr(subs.sender.client)) == NULL)
1481 		goto __end;
1482 	if ((sport = snd_seq_port_use_ptr(sender, subs.sender.port)) == NULL)
1483 		goto __end;
1484 	if ((dport = snd_seq_port_use_ptr(receiver, subs.dest.port)) == NULL)
1485 		goto __end;
1486 
1487 	result = check_subscription_permission(client, sport, dport, &subs);
1488 	if (result < 0)
1489 		goto __end;
1490 
1491 	result = snd_seq_port_disconnect(client, sender, sport, receiver, dport, &subs);
1492 	if (! result) /* broadcast announce */
1493 		snd_seq_client_notify_subscription(SNDRV_SEQ_ADDRESS_SUBSCRIBERS, 0,
1494 						   &subs, SNDRV_SEQ_EVENT_PORT_UNSUBSCRIBED);
1495       __end:
1496       	if (sport)
1497 		snd_seq_port_unlock(sport);
1498 	if (dport)
1499 		snd_seq_port_unlock(dport);
1500 	if (sender)
1501 		snd_seq_client_unlock(sender);
1502 	if (receiver)
1503 		snd_seq_client_unlock(receiver);
1504 	return result;
1505 }
1506 
1507 
1508 /* CREATE_QUEUE ioctl() */
1509 static int snd_seq_ioctl_create_queue(struct snd_seq_client *client,
1510 				      void __user *arg)
1511 {
1512 	struct snd_seq_queue_info info;
1513 	int result;
1514 	struct snd_seq_queue *q;
1515 
1516 	if (copy_from_user(&info, arg, sizeof(info)))
1517 		return -EFAULT;
1518 
1519 	result = snd_seq_queue_alloc(client->number, info.locked, info.flags);
1520 	if (result < 0)
1521 		return result;
1522 
1523 	q = queueptr(result);
1524 	if (q == NULL)
1525 		return -EINVAL;
1526 
1527 	info.queue = q->queue;
1528 	info.locked = q->locked;
1529 	info.owner = q->owner;
1530 
1531 	/* set queue name */
1532 	if (! info.name[0])
1533 		snprintf(info.name, sizeof(info.name), "Queue-%d", q->queue);
1534 	strlcpy(q->name, info.name, sizeof(q->name));
1535 	queuefree(q);
1536 
1537 	if (copy_to_user(arg, &info, sizeof(info)))
1538 		return -EFAULT;
1539 
1540 	return 0;
1541 }
1542 
1543 /* DELETE_QUEUE ioctl() */
1544 static int snd_seq_ioctl_delete_queue(struct snd_seq_client *client,
1545 				      void __user *arg)
1546 {
1547 	struct snd_seq_queue_info info;
1548 
1549 	if (copy_from_user(&info, arg, sizeof(info)))
1550 		return -EFAULT;
1551 
1552 	return snd_seq_queue_delete(client->number, info.queue);
1553 }
1554 
1555 /* GET_QUEUE_INFO ioctl() */
1556 static int snd_seq_ioctl_get_queue_info(struct snd_seq_client *client,
1557 					void __user *arg)
1558 {
1559 	struct snd_seq_queue_info info;
1560 	struct snd_seq_queue *q;
1561 
1562 	if (copy_from_user(&info, arg, sizeof(info)))
1563 		return -EFAULT;
1564 
1565 	q = queueptr(info.queue);
1566 	if (q == NULL)
1567 		return -EINVAL;
1568 
1569 	memset(&info, 0, sizeof(info));
1570 	info.queue = q->queue;
1571 	info.owner = q->owner;
1572 	info.locked = q->locked;
1573 	strlcpy(info.name, q->name, sizeof(info.name));
1574 	queuefree(q);
1575 
1576 	if (copy_to_user(arg, &info, sizeof(info)))
1577 		return -EFAULT;
1578 
1579 	return 0;
1580 }
1581 
1582 /* SET_QUEUE_INFO ioctl() */
1583 static int snd_seq_ioctl_set_queue_info(struct snd_seq_client *client,
1584 					void __user *arg)
1585 {
1586 	struct snd_seq_queue_info info;
1587 	struct snd_seq_queue *q;
1588 
1589 	if (copy_from_user(&info, arg, sizeof(info)))
1590 		return -EFAULT;
1591 
1592 	if (info.owner != client->number)
1593 		return -EINVAL;
1594 
1595 	/* change owner/locked permission */
1596 	if (snd_seq_queue_check_access(info.queue, client->number)) {
1597 		if (snd_seq_queue_set_owner(info.queue, client->number, info.locked) < 0)
1598 			return -EPERM;
1599 		if (info.locked)
1600 			snd_seq_queue_use(info.queue, client->number, 1);
1601 	} else {
1602 		return -EPERM;
1603 	}
1604 
1605 	q = queueptr(info.queue);
1606 	if (! q)
1607 		return -EINVAL;
1608 	if (q->owner != client->number) {
1609 		queuefree(q);
1610 		return -EPERM;
1611 	}
1612 	strlcpy(q->name, info.name, sizeof(q->name));
1613 	queuefree(q);
1614 
1615 	return 0;
1616 }
1617 
1618 /* GET_NAMED_QUEUE ioctl() */
1619 static int snd_seq_ioctl_get_named_queue(struct snd_seq_client *client, void __user *arg)
1620 {
1621 	struct snd_seq_queue_info info;
1622 	struct snd_seq_queue *q;
1623 
1624 	if (copy_from_user(&info, arg, sizeof(info)))
1625 		return -EFAULT;
1626 
1627 	q = snd_seq_queue_find_name(info.name);
1628 	if (q == NULL)
1629 		return -EINVAL;
1630 	info.queue = q->queue;
1631 	info.owner = q->owner;
1632 	info.locked = q->locked;
1633 	queuefree(q);
1634 
1635 	if (copy_to_user(arg, &info, sizeof(info)))
1636 		return -EFAULT;
1637 
1638 	return 0;
1639 }
1640 
1641 /* GET_QUEUE_STATUS ioctl() */
1642 static int snd_seq_ioctl_get_queue_status(struct snd_seq_client *client,
1643 					  void __user *arg)
1644 {
1645 	struct snd_seq_queue_status status;
1646 	struct snd_seq_queue *queue;
1647 	struct snd_seq_timer *tmr;
1648 
1649 	if (copy_from_user(&status, arg, sizeof(status)))
1650 		return -EFAULT;
1651 
1652 	queue = queueptr(status.queue);
1653 	if (queue == NULL)
1654 		return -EINVAL;
1655 	memset(&status, 0, sizeof(status));
1656 	status.queue = queue->queue;
1657 
1658 	tmr = queue->timer;
1659 	status.events = queue->tickq->cells + queue->timeq->cells;
1660 
1661 	status.time = snd_seq_timer_get_cur_time(tmr);
1662 	status.tick = snd_seq_timer_get_cur_tick(tmr);
1663 
1664 	status.running = tmr->running;
1665 
1666 	status.flags = queue->flags;
1667 	queuefree(queue);
1668 
1669 	if (copy_to_user(arg, &status, sizeof(status)))
1670 		return -EFAULT;
1671 	return 0;
1672 }
1673 
1674 
1675 /* GET_QUEUE_TEMPO ioctl() */
1676 static int snd_seq_ioctl_get_queue_tempo(struct snd_seq_client *client,
1677 					 void __user *arg)
1678 {
1679 	struct snd_seq_queue_tempo tempo;
1680 	struct snd_seq_queue *queue;
1681 	struct snd_seq_timer *tmr;
1682 
1683 	if (copy_from_user(&tempo, arg, sizeof(tempo)))
1684 		return -EFAULT;
1685 
1686 	queue = queueptr(tempo.queue);
1687 	if (queue == NULL)
1688 		return -EINVAL;
1689 	memset(&tempo, 0, sizeof(tempo));
1690 	tempo.queue = queue->queue;
1691 
1692 	tmr = queue->timer;
1693 
1694 	tempo.tempo = tmr->tempo;
1695 	tempo.ppq = tmr->ppq;
1696 	tempo.skew_value = tmr->skew;
1697 	tempo.skew_base = tmr->skew_base;
1698 	queuefree(queue);
1699 
1700 	if (copy_to_user(arg, &tempo, sizeof(tempo)))
1701 		return -EFAULT;
1702 	return 0;
1703 }
1704 
1705 
1706 /* SET_QUEUE_TEMPO ioctl() */
1707 int snd_seq_set_queue_tempo(int client, struct snd_seq_queue_tempo *tempo)
1708 {
1709 	if (!snd_seq_queue_check_access(tempo->queue, client))
1710 		return -EPERM;
1711 	return snd_seq_queue_timer_set_tempo(tempo->queue, client, tempo);
1712 }
1713 
1714 EXPORT_SYMBOL(snd_seq_set_queue_tempo);
1715 
1716 static int snd_seq_ioctl_set_queue_tempo(struct snd_seq_client *client,
1717 					 void __user *arg)
1718 {
1719 	int result;
1720 	struct snd_seq_queue_tempo tempo;
1721 
1722 	if (copy_from_user(&tempo, arg, sizeof(tempo)))
1723 		return -EFAULT;
1724 
1725 	result = snd_seq_set_queue_tempo(client->number, &tempo);
1726 	return result < 0 ? result : 0;
1727 }
1728 
1729 
1730 /* GET_QUEUE_TIMER ioctl() */
1731 static int snd_seq_ioctl_get_queue_timer(struct snd_seq_client *client,
1732 					 void __user *arg)
1733 {
1734 	struct snd_seq_queue_timer timer;
1735 	struct snd_seq_queue *queue;
1736 	struct snd_seq_timer *tmr;
1737 
1738 	if (copy_from_user(&timer, arg, sizeof(timer)))
1739 		return -EFAULT;
1740 
1741 	queue = queueptr(timer.queue);
1742 	if (queue == NULL)
1743 		return -EINVAL;
1744 
1745 	if (mutex_lock_interruptible(&queue->timer_mutex)) {
1746 		queuefree(queue);
1747 		return -ERESTARTSYS;
1748 	}
1749 	tmr = queue->timer;
1750 	memset(&timer, 0, sizeof(timer));
1751 	timer.queue = queue->queue;
1752 
1753 	timer.type = tmr->type;
1754 	if (tmr->type == SNDRV_SEQ_TIMER_ALSA) {
1755 		timer.u.alsa.id = tmr->alsa_id;
1756 		timer.u.alsa.resolution = tmr->preferred_resolution;
1757 	}
1758 	mutex_unlock(&queue->timer_mutex);
1759 	queuefree(queue);
1760 
1761 	if (copy_to_user(arg, &timer, sizeof(timer)))
1762 		return -EFAULT;
1763 	return 0;
1764 }
1765 
1766 
1767 /* SET_QUEUE_TIMER ioctl() */
1768 static int snd_seq_ioctl_set_queue_timer(struct snd_seq_client *client,
1769 					 void __user *arg)
1770 {
1771 	int result = 0;
1772 	struct snd_seq_queue_timer timer;
1773 
1774 	if (copy_from_user(&timer, arg, sizeof(timer)))
1775 		return -EFAULT;
1776 
1777 	if (timer.type != SNDRV_SEQ_TIMER_ALSA)
1778 		return -EINVAL;
1779 
1780 	if (snd_seq_queue_check_access(timer.queue, client->number)) {
1781 		struct snd_seq_queue *q;
1782 		struct snd_seq_timer *tmr;
1783 
1784 		q = queueptr(timer.queue);
1785 		if (q == NULL)
1786 			return -ENXIO;
1787 		if (mutex_lock_interruptible(&q->timer_mutex)) {
1788 			queuefree(q);
1789 			return -ERESTARTSYS;
1790 		}
1791 		tmr = q->timer;
1792 		snd_seq_queue_timer_close(timer.queue);
1793 		tmr->type = timer.type;
1794 		if (tmr->type == SNDRV_SEQ_TIMER_ALSA) {
1795 			tmr->alsa_id = timer.u.alsa.id;
1796 			tmr->preferred_resolution = timer.u.alsa.resolution;
1797 		}
1798 		result = snd_seq_queue_timer_open(timer.queue);
1799 		mutex_unlock(&q->timer_mutex);
1800 		queuefree(q);
1801 	} else {
1802 		return -EPERM;
1803 	}
1804 
1805 	return result;
1806 }
1807 
1808 
1809 /* GET_QUEUE_CLIENT ioctl() */
1810 static int snd_seq_ioctl_get_queue_client(struct snd_seq_client *client,
1811 					  void __user *arg)
1812 {
1813 	struct snd_seq_queue_client info;
1814 	int used;
1815 
1816 	if (copy_from_user(&info, arg, sizeof(info)))
1817 		return -EFAULT;
1818 
1819 	used = snd_seq_queue_is_used(info.queue, client->number);
1820 	if (used < 0)
1821 		return -EINVAL;
1822 	info.used = used;
1823 	info.client = client->number;
1824 
1825 	if (copy_to_user(arg, &info, sizeof(info)))
1826 		return -EFAULT;
1827 	return 0;
1828 }
1829 
1830 
1831 /* SET_QUEUE_CLIENT ioctl() */
1832 static int snd_seq_ioctl_set_queue_client(struct snd_seq_client *client,
1833 					  void __user *arg)
1834 {
1835 	int err;
1836 	struct snd_seq_queue_client info;
1837 
1838 	if (copy_from_user(&info, arg, sizeof(info)))
1839 		return -EFAULT;
1840 
1841 	if (info.used >= 0) {
1842 		err = snd_seq_queue_use(info.queue, client->number, info.used);
1843 		if (err < 0)
1844 			return err;
1845 	}
1846 
1847 	return snd_seq_ioctl_get_queue_client(client, arg);
1848 }
1849 
1850 
1851 /* GET_CLIENT_POOL ioctl() */
1852 static int snd_seq_ioctl_get_client_pool(struct snd_seq_client *client,
1853 					 void __user *arg)
1854 {
1855 	struct snd_seq_client_pool info;
1856 	struct snd_seq_client *cptr;
1857 
1858 	if (copy_from_user(&info, arg, sizeof(info)))
1859 		return -EFAULT;
1860 
1861 	cptr = snd_seq_client_use_ptr(info.client);
1862 	if (cptr == NULL)
1863 		return -ENOENT;
1864 	memset(&info, 0, sizeof(info));
1865 	info.output_pool = cptr->pool->size;
1866 	info.output_room = cptr->pool->room;
1867 	info.output_free = info.output_pool;
1868 	info.output_free = snd_seq_unused_cells(cptr->pool);
1869 	if (cptr->type == USER_CLIENT) {
1870 		info.input_pool = cptr->data.user.fifo_pool_size;
1871 		info.input_free = info.input_pool;
1872 		if (cptr->data.user.fifo)
1873 			info.input_free = snd_seq_unused_cells(cptr->data.user.fifo->pool);
1874 	} else {
1875 		info.input_pool = 0;
1876 		info.input_free = 0;
1877 	}
1878 	snd_seq_client_unlock(cptr);
1879 
1880 	if (copy_to_user(arg, &info, sizeof(info)))
1881 		return -EFAULT;
1882 	return 0;
1883 }
1884 
1885 /* SET_CLIENT_POOL ioctl() */
1886 static int snd_seq_ioctl_set_client_pool(struct snd_seq_client *client,
1887 					 void __user *arg)
1888 {
1889 	struct snd_seq_client_pool info;
1890 	int rc;
1891 
1892 	if (copy_from_user(&info, arg, sizeof(info)))
1893 		return -EFAULT;
1894 
1895 	if (client->number != info.client)
1896 		return -EINVAL; /* can't change other clients */
1897 
1898 	if (info.output_pool >= 1 && info.output_pool <= SNDRV_SEQ_MAX_EVENTS &&
1899 	    (! snd_seq_write_pool_allocated(client) ||
1900 	     info.output_pool != client->pool->size)) {
1901 		if (snd_seq_write_pool_allocated(client)) {
1902 			/* remove all existing cells */
1903 			snd_seq_queue_client_leave_cells(client->number);
1904 			snd_seq_pool_done(client->pool);
1905 		}
1906 		client->pool->size = info.output_pool;
1907 		rc = snd_seq_pool_init(client->pool);
1908 		if (rc < 0)
1909 			return rc;
1910 	}
1911 	if (client->type == USER_CLIENT && client->data.user.fifo != NULL &&
1912 	    info.input_pool >= 1 &&
1913 	    info.input_pool <= SNDRV_SEQ_MAX_CLIENT_EVENTS &&
1914 	    info.input_pool != client->data.user.fifo_pool_size) {
1915 		/* change pool size */
1916 		rc = snd_seq_fifo_resize(client->data.user.fifo, info.input_pool);
1917 		if (rc < 0)
1918 			return rc;
1919 		client->data.user.fifo_pool_size = info.input_pool;
1920 	}
1921 	if (info.output_room >= 1 &&
1922 	    info.output_room <= client->pool->size) {
1923 		client->pool->room  = info.output_room;
1924 	}
1925 
1926 	return snd_seq_ioctl_get_client_pool(client, arg);
1927 }
1928 
1929 
1930 /* REMOVE_EVENTS ioctl() */
1931 static int snd_seq_ioctl_remove_events(struct snd_seq_client *client,
1932 				       void __user *arg)
1933 {
1934 	struct snd_seq_remove_events info;
1935 
1936 	if (copy_from_user(&info, arg, sizeof(info)))
1937 		return -EFAULT;
1938 
1939 	/*
1940 	 * Input mostly not implemented XXX.
1941 	 */
1942 	if (info.remove_mode & SNDRV_SEQ_REMOVE_INPUT) {
1943 		/*
1944 		 * No restrictions so for a user client we can clear
1945 		 * the whole fifo
1946 		 */
1947 		if (client->type == USER_CLIENT)
1948 			snd_seq_fifo_clear(client->data.user.fifo);
1949 	}
1950 
1951 	if (info.remove_mode & SNDRV_SEQ_REMOVE_OUTPUT)
1952 		snd_seq_queue_remove_cells(client->number, &info);
1953 
1954 	return 0;
1955 }
1956 
1957 
1958 /*
1959  * get subscription info
1960  */
1961 static int snd_seq_ioctl_get_subscription(struct snd_seq_client *client,
1962 					  void __user *arg)
1963 {
1964 	int result;
1965 	struct snd_seq_client *sender = NULL;
1966 	struct snd_seq_client_port *sport = NULL;
1967 	struct snd_seq_port_subscribe subs;
1968 	struct snd_seq_subscribers *p;
1969 
1970 	if (copy_from_user(&subs, arg, sizeof(subs)))
1971 		return -EFAULT;
1972 
1973 	result = -EINVAL;
1974 	if ((sender = snd_seq_client_use_ptr(subs.sender.client)) == NULL)
1975 		goto __end;
1976 	if ((sport = snd_seq_port_use_ptr(sender, subs.sender.port)) == NULL)
1977 		goto __end;
1978 	p = snd_seq_port_get_subscription(&sport->c_src, &subs.dest);
1979 	if (p) {
1980 		result = 0;
1981 		subs = p->info;
1982 	} else
1983 		result = -ENOENT;
1984 
1985       __end:
1986       	if (sport)
1987 		snd_seq_port_unlock(sport);
1988 	if (sender)
1989 		snd_seq_client_unlock(sender);
1990 	if (result >= 0) {
1991 		if (copy_to_user(arg, &subs, sizeof(subs)))
1992 			return -EFAULT;
1993 	}
1994 	return result;
1995 }
1996 
1997 
1998 /*
1999  * get subscription info - check only its presence
2000  */
2001 static int snd_seq_ioctl_query_subs(struct snd_seq_client *client,
2002 				    void __user *arg)
2003 {
2004 	int result = -ENXIO;
2005 	struct snd_seq_client *cptr = NULL;
2006 	struct snd_seq_client_port *port = NULL;
2007 	struct snd_seq_query_subs subs;
2008 	struct snd_seq_port_subs_info *group;
2009 	struct list_head *p;
2010 	int i;
2011 
2012 	if (copy_from_user(&subs, arg, sizeof(subs)))
2013 		return -EFAULT;
2014 
2015 	if ((cptr = snd_seq_client_use_ptr(subs.root.client)) == NULL)
2016 		goto __end;
2017 	if ((port = snd_seq_port_use_ptr(cptr, subs.root.port)) == NULL)
2018 		goto __end;
2019 
2020 	switch (subs.type) {
2021 	case SNDRV_SEQ_QUERY_SUBS_READ:
2022 		group = &port->c_src;
2023 		break;
2024 	case SNDRV_SEQ_QUERY_SUBS_WRITE:
2025 		group = &port->c_dest;
2026 		break;
2027 	default:
2028 		goto __end;
2029 	}
2030 
2031 	down_read(&group->list_mutex);
2032 	/* search for the subscriber */
2033 	subs.num_subs = group->count;
2034 	i = 0;
2035 	result = -ENOENT;
2036 	list_for_each(p, &group->list_head) {
2037 		if (i++ == subs.index) {
2038 			/* found! */
2039 			struct snd_seq_subscribers *s;
2040 			if (subs.type == SNDRV_SEQ_QUERY_SUBS_READ) {
2041 				s = list_entry(p, struct snd_seq_subscribers, src_list);
2042 				subs.addr = s->info.dest;
2043 			} else {
2044 				s = list_entry(p, struct snd_seq_subscribers, dest_list);
2045 				subs.addr = s->info.sender;
2046 			}
2047 			subs.flags = s->info.flags;
2048 			subs.queue = s->info.queue;
2049 			result = 0;
2050 			break;
2051 		}
2052 	}
2053 	up_read(&group->list_mutex);
2054 
2055       __end:
2056    	if (port)
2057 		snd_seq_port_unlock(port);
2058 	if (cptr)
2059 		snd_seq_client_unlock(cptr);
2060 	if (result >= 0) {
2061 		if (copy_to_user(arg, &subs, sizeof(subs)))
2062 			return -EFAULT;
2063 	}
2064 	return result;
2065 }
2066 
2067 
2068 /*
2069  * query next client
2070  */
2071 static int snd_seq_ioctl_query_next_client(struct snd_seq_client *client,
2072 					   void __user *arg)
2073 {
2074 	struct snd_seq_client *cptr = NULL;
2075 	struct snd_seq_client_info info;
2076 
2077 	if (copy_from_user(&info, arg, sizeof(info)))
2078 		return -EFAULT;
2079 
2080 	/* search for next client */
2081 	info.client++;
2082 	if (info.client < 0)
2083 		info.client = 0;
2084 	for (; info.client < SNDRV_SEQ_MAX_CLIENTS; info.client++) {
2085 		cptr = snd_seq_client_use_ptr(info.client);
2086 		if (cptr)
2087 			break; /* found */
2088 	}
2089 	if (cptr == NULL)
2090 		return -ENOENT;
2091 
2092 	get_client_info(cptr, &info);
2093 	snd_seq_client_unlock(cptr);
2094 
2095 	if (copy_to_user(arg, &info, sizeof(info)))
2096 		return -EFAULT;
2097 	return 0;
2098 }
2099 
2100 /*
2101  * query next port
2102  */
2103 static int snd_seq_ioctl_query_next_port(struct snd_seq_client *client,
2104 					 void __user *arg)
2105 {
2106 	struct snd_seq_client *cptr;
2107 	struct snd_seq_client_port *port = NULL;
2108 	struct snd_seq_port_info info;
2109 
2110 	if (copy_from_user(&info, arg, sizeof(info)))
2111 		return -EFAULT;
2112 	cptr = snd_seq_client_use_ptr(info.addr.client);
2113 	if (cptr == NULL)
2114 		return -ENXIO;
2115 
2116 	/* search for next port */
2117 	info.addr.port++;
2118 	port = snd_seq_port_query_nearest(cptr, &info);
2119 	if (port == NULL) {
2120 		snd_seq_client_unlock(cptr);
2121 		return -ENOENT;
2122 	}
2123 
2124 	/* get port info */
2125 	info.addr = port->addr;
2126 	snd_seq_get_port_info(port, &info);
2127 	snd_seq_port_unlock(port);
2128 	snd_seq_client_unlock(cptr);
2129 
2130 	if (copy_to_user(arg, &info, sizeof(info)))
2131 		return -EFAULT;
2132 	return 0;
2133 }
2134 
2135 /* -------------------------------------------------------- */
2136 
2137 static struct seq_ioctl_table {
2138 	unsigned int cmd;
2139 	int (*func)(struct snd_seq_client *client, void __user * arg);
2140 } ioctl_tables[] = {
2141 	{ SNDRV_SEQ_IOCTL_SYSTEM_INFO, snd_seq_ioctl_system_info },
2142 	{ SNDRV_SEQ_IOCTL_RUNNING_MODE, snd_seq_ioctl_running_mode },
2143 	{ SNDRV_SEQ_IOCTL_GET_CLIENT_INFO, snd_seq_ioctl_get_client_info },
2144 	{ SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, snd_seq_ioctl_set_client_info },
2145 	{ SNDRV_SEQ_IOCTL_CREATE_PORT, snd_seq_ioctl_create_port },
2146 	{ SNDRV_SEQ_IOCTL_DELETE_PORT, snd_seq_ioctl_delete_port },
2147 	{ SNDRV_SEQ_IOCTL_GET_PORT_INFO, snd_seq_ioctl_get_port_info },
2148 	{ SNDRV_SEQ_IOCTL_SET_PORT_INFO, snd_seq_ioctl_set_port_info },
2149 	{ SNDRV_SEQ_IOCTL_SUBSCRIBE_PORT, snd_seq_ioctl_subscribe_port },
2150 	{ SNDRV_SEQ_IOCTL_UNSUBSCRIBE_PORT, snd_seq_ioctl_unsubscribe_port },
2151 	{ SNDRV_SEQ_IOCTL_CREATE_QUEUE, snd_seq_ioctl_create_queue },
2152 	{ SNDRV_SEQ_IOCTL_DELETE_QUEUE, snd_seq_ioctl_delete_queue },
2153 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_INFO, snd_seq_ioctl_get_queue_info },
2154 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_INFO, snd_seq_ioctl_set_queue_info },
2155 	{ SNDRV_SEQ_IOCTL_GET_NAMED_QUEUE, snd_seq_ioctl_get_named_queue },
2156 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_STATUS, snd_seq_ioctl_get_queue_status },
2157 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_TEMPO, snd_seq_ioctl_get_queue_tempo },
2158 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_TEMPO, snd_seq_ioctl_set_queue_tempo },
2159 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_TIMER, snd_seq_ioctl_get_queue_timer },
2160 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_TIMER, snd_seq_ioctl_set_queue_timer },
2161 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_CLIENT, snd_seq_ioctl_get_queue_client },
2162 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_CLIENT, snd_seq_ioctl_set_queue_client },
2163 	{ SNDRV_SEQ_IOCTL_GET_CLIENT_POOL, snd_seq_ioctl_get_client_pool },
2164 	{ SNDRV_SEQ_IOCTL_SET_CLIENT_POOL, snd_seq_ioctl_set_client_pool },
2165 	{ SNDRV_SEQ_IOCTL_GET_SUBSCRIPTION, snd_seq_ioctl_get_subscription },
2166 	{ SNDRV_SEQ_IOCTL_QUERY_NEXT_CLIENT, snd_seq_ioctl_query_next_client },
2167 	{ SNDRV_SEQ_IOCTL_QUERY_NEXT_PORT, snd_seq_ioctl_query_next_port },
2168 	{ SNDRV_SEQ_IOCTL_REMOVE_EVENTS, snd_seq_ioctl_remove_events },
2169 	{ SNDRV_SEQ_IOCTL_QUERY_SUBS, snd_seq_ioctl_query_subs },
2170 	{ 0, NULL },
2171 };
2172 
2173 static int snd_seq_do_ioctl(struct snd_seq_client *client, unsigned int cmd,
2174 			    void __user *arg)
2175 {
2176 	struct seq_ioctl_table *p;
2177 
2178 	switch (cmd) {
2179 	case SNDRV_SEQ_IOCTL_PVERSION:
2180 		/* return sequencer version number */
2181 		return put_user(SNDRV_SEQ_VERSION, (int __user *)arg) ? -EFAULT : 0;
2182 	case SNDRV_SEQ_IOCTL_CLIENT_ID:
2183 		/* return the id of this client */
2184 		return put_user(client->number, (int __user *)arg) ? -EFAULT : 0;
2185 	}
2186 
2187 	if (! arg)
2188 		return -EFAULT;
2189 	for (p = ioctl_tables; p->cmd; p++) {
2190 		if (p->cmd == cmd)
2191 			return p->func(client, arg);
2192 	}
2193 	snd_printd("seq unknown ioctl() 0x%x (type='%c', number=0x%2x)\n",
2194 		   cmd, _IOC_TYPE(cmd), _IOC_NR(cmd));
2195 	return -ENOTTY;
2196 }
2197 
2198 
2199 static long snd_seq_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2200 {
2201 	struct snd_seq_client *client = file->private_data;
2202 
2203 	snd_assert(client != NULL, return -ENXIO);
2204 
2205 	return snd_seq_do_ioctl(client, cmd, (void __user *) arg);
2206 }
2207 
2208 #ifdef CONFIG_COMPAT
2209 #include "seq_compat.c"
2210 #else
2211 #define snd_seq_ioctl_compat	NULL
2212 #endif
2213 
2214 /* -------------------------------------------------------- */
2215 
2216 
2217 /* exported to kernel modules */
2218 int snd_seq_create_kernel_client(struct snd_card *card, int client_index,
2219 				 const char *name_fmt, ...)
2220 {
2221 	struct snd_seq_client *client;
2222 	va_list args;
2223 
2224 	snd_assert(! in_interrupt(), return -EBUSY);
2225 
2226 	if (card && client_index >= SNDRV_SEQ_CLIENTS_PER_CARD)
2227 		return -EINVAL;
2228 	if (card == NULL && client_index >= SNDRV_SEQ_GLOBAL_CLIENTS)
2229 		return -EINVAL;
2230 
2231 	if (mutex_lock_interruptible(&register_mutex))
2232 		return -ERESTARTSYS;
2233 
2234 	if (card) {
2235 		client_index += SNDRV_SEQ_GLOBAL_CLIENTS
2236 			+ card->number * SNDRV_SEQ_CLIENTS_PER_CARD;
2237 		if (client_index >= SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN)
2238 			client_index = -1;
2239 	}
2240 
2241 	/* empty write queue as default */
2242 	client = seq_create_client1(client_index, 0);
2243 	if (client == NULL) {
2244 		mutex_unlock(&register_mutex);
2245 		return -EBUSY;	/* failure code */
2246 	}
2247 	usage_alloc(&client_usage, 1);
2248 
2249 	client->accept_input = 1;
2250 	client->accept_output = 1;
2251 
2252 	va_start(args, name_fmt);
2253 	vsnprintf(client->name, sizeof(client->name), name_fmt, args);
2254 	va_end(args);
2255 
2256 	client->type = KERNEL_CLIENT;
2257 	mutex_unlock(&register_mutex);
2258 
2259 	/* make others aware this new client */
2260 	snd_seq_system_client_ev_client_start(client->number);
2261 
2262 	/* return client number to caller */
2263 	return client->number;
2264 }
2265 
2266 EXPORT_SYMBOL(snd_seq_create_kernel_client);
2267 
2268 /* exported to kernel modules */
2269 int snd_seq_delete_kernel_client(int client)
2270 {
2271 	struct snd_seq_client *ptr;
2272 
2273 	snd_assert(! in_interrupt(), return -EBUSY);
2274 
2275 	ptr = clientptr(client);
2276 	if (ptr == NULL)
2277 		return -EINVAL;
2278 
2279 	seq_free_client(ptr);
2280 	kfree(ptr);
2281 	return 0;
2282 }
2283 
2284 EXPORT_SYMBOL(snd_seq_delete_kernel_client);
2285 
2286 /* skeleton to enqueue event, called from snd_seq_kernel_client_enqueue
2287  * and snd_seq_kernel_client_enqueue_blocking
2288  */
2289 static int kernel_client_enqueue(int client, struct snd_seq_event *ev,
2290 				 struct file *file, int blocking,
2291 				 int atomic, int hop)
2292 {
2293 	struct snd_seq_client *cptr;
2294 	int result;
2295 
2296 	snd_assert(ev != NULL, return -EINVAL);
2297 
2298 	if (ev->type == SNDRV_SEQ_EVENT_NONE)
2299 		return 0; /* ignore this */
2300 	if (ev->type == SNDRV_SEQ_EVENT_KERNEL_ERROR)
2301 		return -EINVAL; /* quoted events can't be enqueued */
2302 
2303 	/* fill in client number */
2304 	ev->source.client = client;
2305 
2306 	if (check_event_type_and_length(ev))
2307 		return -EINVAL;
2308 
2309 	cptr = snd_seq_client_use_ptr(client);
2310 	if (cptr == NULL)
2311 		return -EINVAL;
2312 
2313 	if (! cptr->accept_output)
2314 		result = -EPERM;
2315 	else /* send it */
2316 		result = snd_seq_client_enqueue_event(cptr, ev, file, blocking, atomic, hop);
2317 
2318 	snd_seq_client_unlock(cptr);
2319 	return result;
2320 }
2321 
2322 /*
2323  * exported, called by kernel clients to enqueue events (w/o blocking)
2324  *
2325  * RETURN VALUE: zero if succeed, negative if error
2326  */
2327 int snd_seq_kernel_client_enqueue(int client, struct snd_seq_event * ev,
2328 				  int atomic, int hop)
2329 {
2330 	return kernel_client_enqueue(client, ev, NULL, 0, atomic, hop);
2331 }
2332 
2333 EXPORT_SYMBOL(snd_seq_kernel_client_enqueue);
2334 
2335 /*
2336  * exported, called by kernel clients to enqueue events (with blocking)
2337  *
2338  * RETURN VALUE: zero if succeed, negative if error
2339  */
2340 int snd_seq_kernel_client_enqueue_blocking(int client, struct snd_seq_event * ev,
2341 					   struct file *file,
2342 					   int atomic, int hop)
2343 {
2344 	return kernel_client_enqueue(client, ev, file, 1, atomic, hop);
2345 }
2346 
2347 EXPORT_SYMBOL(snd_seq_kernel_client_enqueue_blocking);
2348 
2349 /*
2350  * exported, called by kernel clients to dispatch events directly to other
2351  * clients, bypassing the queues.  Event time-stamp will be updated.
2352  *
2353  * RETURN VALUE: negative = delivery failed,
2354  *		 zero, or positive: the number of delivered events
2355  */
2356 int snd_seq_kernel_client_dispatch(int client, struct snd_seq_event * ev,
2357 				   int atomic, int hop)
2358 {
2359 	struct snd_seq_client *cptr;
2360 	int result;
2361 
2362 	snd_assert(ev != NULL, return -EINVAL);
2363 
2364 	/* fill in client number */
2365 	ev->queue = SNDRV_SEQ_QUEUE_DIRECT;
2366 	ev->source.client = client;
2367 
2368 	if (check_event_type_and_length(ev))
2369 		return -EINVAL;
2370 
2371 	cptr = snd_seq_client_use_ptr(client);
2372 	if (cptr == NULL)
2373 		return -EINVAL;
2374 
2375 	if (!cptr->accept_output)
2376 		result = -EPERM;
2377 	else
2378 		result = snd_seq_deliver_event(cptr, ev, atomic, hop);
2379 
2380 	snd_seq_client_unlock(cptr);
2381 	return result;
2382 }
2383 
2384 EXPORT_SYMBOL(snd_seq_kernel_client_dispatch);
2385 
2386 /*
2387  * exported, called by kernel clients to perform same functions as with
2388  * userland ioctl()
2389  */
2390 int snd_seq_kernel_client_ctl(int clientid, unsigned int cmd, void *arg)
2391 {
2392 	struct snd_seq_client *client;
2393 	mm_segment_t fs;
2394 	int result;
2395 
2396 	client = clientptr(clientid);
2397 	if (client == NULL)
2398 		return -ENXIO;
2399 	fs = snd_enter_user();
2400 	result = snd_seq_do_ioctl(client, cmd, (void __user *)arg);
2401 	snd_leave_user(fs);
2402 	return result;
2403 }
2404 
2405 EXPORT_SYMBOL(snd_seq_kernel_client_ctl);
2406 
2407 /* exported (for OSS emulator) */
2408 int snd_seq_kernel_client_write_poll(int clientid, struct file *file, poll_table *wait)
2409 {
2410 	struct snd_seq_client *client;
2411 
2412 	client = clientptr(clientid);
2413 	if (client == NULL)
2414 		return -ENXIO;
2415 
2416 	if (! snd_seq_write_pool_allocated(client))
2417 		return 1;
2418 	if (snd_seq_pool_poll_wait(client->pool, file, wait))
2419 		return 1;
2420 	return 0;
2421 }
2422 
2423 EXPORT_SYMBOL(snd_seq_kernel_client_write_poll);
2424 
2425 /*---------------------------------------------------------------------------*/
2426 
2427 #ifdef CONFIG_PROC_FS
2428 /*
2429  *  /proc interface
2430  */
2431 static void snd_seq_info_dump_subscribers(struct snd_info_buffer *buffer,
2432 					  struct snd_seq_port_subs_info *group,
2433 					  int is_src, char *msg)
2434 {
2435 	struct list_head *p;
2436 	struct snd_seq_subscribers *s;
2437 	int count = 0;
2438 
2439 	down_read(&group->list_mutex);
2440 	if (list_empty(&group->list_head)) {
2441 		up_read(&group->list_mutex);
2442 		return;
2443 	}
2444 	snd_iprintf(buffer, msg);
2445 	list_for_each(p, &group->list_head) {
2446 		if (is_src)
2447 			s = list_entry(p, struct snd_seq_subscribers, src_list);
2448 		else
2449 			s = list_entry(p, struct snd_seq_subscribers, dest_list);
2450 		if (count++)
2451 			snd_iprintf(buffer, ", ");
2452 		snd_iprintf(buffer, "%d:%d",
2453 			    is_src ? s->info.dest.client : s->info.sender.client,
2454 			    is_src ? s->info.dest.port : s->info.sender.port);
2455 		if (s->info.flags & SNDRV_SEQ_PORT_SUBS_TIMESTAMP)
2456 			snd_iprintf(buffer, "[%c:%d]", ((s->info.flags & SNDRV_SEQ_PORT_SUBS_TIME_REAL) ? 'r' : 't'), s->info.queue);
2457 		if (group->exclusive)
2458 			snd_iprintf(buffer, "[ex]");
2459 	}
2460 	up_read(&group->list_mutex);
2461 	snd_iprintf(buffer, "\n");
2462 }
2463 
2464 #define FLAG_PERM_RD(perm) ((perm) & SNDRV_SEQ_PORT_CAP_READ ? ((perm) & SNDRV_SEQ_PORT_CAP_SUBS_READ ? 'R' : 'r') : '-')
2465 #define FLAG_PERM_WR(perm) ((perm) & SNDRV_SEQ_PORT_CAP_WRITE ? ((perm) & SNDRV_SEQ_PORT_CAP_SUBS_WRITE ? 'W' : 'w') : '-')
2466 #define FLAG_PERM_EX(perm) ((perm) & SNDRV_SEQ_PORT_CAP_NO_EXPORT ? '-' : 'e')
2467 
2468 #define FLAG_PERM_DUPLEX(perm) ((perm) & SNDRV_SEQ_PORT_CAP_DUPLEX ? 'X' : '-')
2469 
2470 static void snd_seq_info_dump_ports(struct snd_info_buffer *buffer,
2471 				    struct snd_seq_client *client)
2472 {
2473 	struct snd_seq_client_port *p;
2474 
2475 	mutex_lock(&client->ports_mutex);
2476 	list_for_each_entry(p, &client->ports_list_head, list) {
2477 		snd_iprintf(buffer, "  Port %3d : \"%s\" (%c%c%c%c)\n",
2478 			    p->addr.port, p->name,
2479 			    FLAG_PERM_RD(p->capability),
2480 			    FLAG_PERM_WR(p->capability),
2481 			    FLAG_PERM_EX(p->capability),
2482 			    FLAG_PERM_DUPLEX(p->capability));
2483 		snd_seq_info_dump_subscribers(buffer, &p->c_src, 1, "    Connecting To: ");
2484 		snd_seq_info_dump_subscribers(buffer, &p->c_dest, 0, "    Connected From: ");
2485 	}
2486 	mutex_unlock(&client->ports_mutex);
2487 }
2488 
2489 
2490 void snd_seq_info_pool(struct snd_info_buffer *buffer,
2491 		       struct snd_seq_pool *pool, char *space);
2492 
2493 /* exported to seq_info.c */
2494 void snd_seq_info_clients_read(struct snd_info_entry *entry,
2495 			       struct snd_info_buffer *buffer)
2496 {
2497 	int c;
2498 	struct snd_seq_client *client;
2499 
2500 	snd_iprintf(buffer, "Client info\n");
2501 	snd_iprintf(buffer, "  cur  clients : %d\n", client_usage.cur);
2502 	snd_iprintf(buffer, "  peak clients : %d\n", client_usage.peak);
2503 	snd_iprintf(buffer, "  max  clients : %d\n", SNDRV_SEQ_MAX_CLIENTS);
2504 	snd_iprintf(buffer, "\n");
2505 
2506 	/* list the client table */
2507 	for (c = 0; c < SNDRV_SEQ_MAX_CLIENTS; c++) {
2508 		client = snd_seq_client_use_ptr(c);
2509 		if (client == NULL)
2510 			continue;
2511 		if (client->type == NO_CLIENT) {
2512 			snd_seq_client_unlock(client);
2513 			continue;
2514 		}
2515 
2516 		snd_iprintf(buffer, "Client %3d : \"%s\" [%s]\n",
2517 			    c, client->name,
2518 			    client->type == USER_CLIENT ? "User" : "Kernel");
2519 		snd_seq_info_dump_ports(buffer, client);
2520 		if (snd_seq_write_pool_allocated(client)) {
2521 			snd_iprintf(buffer, "  Output pool :\n");
2522 			snd_seq_info_pool(buffer, client->pool, "    ");
2523 		}
2524 		if (client->type == USER_CLIENT && client->data.user.fifo &&
2525 		    client->data.user.fifo->pool) {
2526 			snd_iprintf(buffer, "  Input pool :\n");
2527 			snd_seq_info_pool(buffer, client->data.user.fifo->pool, "    ");
2528 		}
2529 		snd_seq_client_unlock(client);
2530 	}
2531 }
2532 #endif /* CONFIG_PROC_FS */
2533 
2534 /*---------------------------------------------------------------------------*/
2535 
2536 
2537 /*
2538  *  REGISTRATION PART
2539  */
2540 
2541 static const struct file_operations snd_seq_f_ops =
2542 {
2543 	.owner =	THIS_MODULE,
2544 	.read =		snd_seq_read,
2545 	.write =	snd_seq_write,
2546 	.open =		snd_seq_open,
2547 	.release =	snd_seq_release,
2548 	.poll =		snd_seq_poll,
2549 	.unlocked_ioctl =	snd_seq_ioctl,
2550 	.compat_ioctl =	snd_seq_ioctl_compat,
2551 };
2552 
2553 /*
2554  * register sequencer device
2555  */
2556 int __init snd_sequencer_device_init(void)
2557 {
2558 	int err;
2559 
2560 	if (mutex_lock_interruptible(&register_mutex))
2561 		return -ERESTARTSYS;
2562 
2563 	if ((err = snd_register_device(SNDRV_DEVICE_TYPE_SEQUENCER, NULL, 0,
2564 				       &snd_seq_f_ops, NULL, "seq")) < 0) {
2565 		mutex_unlock(&register_mutex);
2566 		return err;
2567 	}
2568 
2569 	mutex_unlock(&register_mutex);
2570 
2571 	return 0;
2572 }
2573 
2574 
2575 
2576 /*
2577  * unregister sequencer device
2578  */
2579 void __exit snd_sequencer_device_done(void)
2580 {
2581 	snd_unregister_device(SNDRV_DEVICE_TYPE_SEQUENCER, NULL, 0);
2582 }
2583