xref: /linux/sound/core/seq/seq_clientmgr.c (revision 18f90d372cf35b387663f1567de701e5393f6eb5)
1 /*
2  *  ALSA sequencer Client Manager
3  *  Copyright (c) 1998-2001 by Frank van de Pol <fvdpol@coil.demon.nl>
4  *                             Jaroslav Kysela <perex@perex.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 <linux/init.h>
25 #include <linux/export.h>
26 #include <linux/slab.h>
27 #include <sound/core.h>
28 #include <sound/minors.h>
29 #include <linux/kmod.h>
30 
31 #include <sound/seq_kernel.h>
32 #include "seq_clientmgr.h"
33 #include "seq_memory.h"
34 #include "seq_queue.h"
35 #include "seq_timer.h"
36 #include "seq_info.h"
37 #include "seq_system.h"
38 #include <sound/seq_device.h>
39 #ifdef CONFIG_COMPAT
40 #include <linux/compat.h>
41 #endif
42 
43 /* Client Manager
44 
45  * this module handles the connections of userland and kernel clients
46  *
47  */
48 
49 /*
50  * There are four ranges of client numbers (last two shared):
51  * 0..15: global clients
52  * 16..127: statically allocated client numbers for cards 0..27
53  * 128..191: dynamically allocated client numbers for cards 28..31
54  * 128..191: dynamically allocated client numbers for applications
55  */
56 
57 /* number of kernel non-card clients */
58 #define SNDRV_SEQ_GLOBAL_CLIENTS	16
59 /* clients per cards, for static clients */
60 #define SNDRV_SEQ_CLIENTS_PER_CARD	4
61 /* dynamically allocated client numbers (both kernel drivers and user space) */
62 #define SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN	128
63 
64 #define SNDRV_SEQ_LFLG_INPUT	0x0001
65 #define SNDRV_SEQ_LFLG_OUTPUT	0x0002
66 #define SNDRV_SEQ_LFLG_OPEN	(SNDRV_SEQ_LFLG_INPUT|SNDRV_SEQ_LFLG_OUTPUT)
67 
68 static DEFINE_SPINLOCK(clients_lock);
69 static DEFINE_MUTEX(register_mutex);
70 
71 /*
72  * client table
73  */
74 static char clienttablock[SNDRV_SEQ_MAX_CLIENTS];
75 static struct snd_seq_client *clienttab[SNDRV_SEQ_MAX_CLIENTS];
76 static struct snd_seq_usage client_usage;
77 
78 /*
79  * prototypes
80  */
81 static int bounce_error_event(struct snd_seq_client *client,
82 			      struct snd_seq_event *event,
83 			      int err, int atomic, int hop);
84 static int snd_seq_deliver_single_event(struct snd_seq_client *client,
85 					struct snd_seq_event *event,
86 					int filter, int atomic, int hop);
87 
88 /*
89  */
90 static inline unsigned short snd_seq_file_flags(struct file *file)
91 {
92         switch (file->f_mode & (FMODE_READ | FMODE_WRITE)) {
93         case FMODE_WRITE:
94                 return SNDRV_SEQ_LFLG_OUTPUT;
95         case FMODE_READ:
96                 return SNDRV_SEQ_LFLG_INPUT;
97         default:
98                 return SNDRV_SEQ_LFLG_OPEN;
99         }
100 }
101 
102 static inline int snd_seq_write_pool_allocated(struct snd_seq_client *client)
103 {
104 	return snd_seq_total_cells(client->pool) > 0;
105 }
106 
107 /* return pointer to client structure for specified id */
108 static struct snd_seq_client *clientptr(int clientid)
109 {
110 	if (clientid < 0 || clientid >= SNDRV_SEQ_MAX_CLIENTS) {
111 		pr_debug("ALSA: seq: oops. Trying to get pointer to client %d\n",
112 			   clientid);
113 		return NULL;
114 	}
115 	return clienttab[clientid];
116 }
117 
118 struct snd_seq_client *snd_seq_client_use_ptr(int clientid)
119 {
120 	unsigned long flags;
121 	struct snd_seq_client *client;
122 
123 	if (clientid < 0 || clientid >= SNDRV_SEQ_MAX_CLIENTS) {
124 		pr_debug("ALSA: seq: oops. Trying to get pointer to client %d\n",
125 			   clientid);
126 		return NULL;
127 	}
128 	spin_lock_irqsave(&clients_lock, flags);
129 	client = clientptr(clientid);
130 	if (client)
131 		goto __lock;
132 	if (clienttablock[clientid]) {
133 		spin_unlock_irqrestore(&clients_lock, flags);
134 		return NULL;
135 	}
136 	spin_unlock_irqrestore(&clients_lock, flags);
137 #ifdef CONFIG_MODULES
138 	if (!in_interrupt()) {
139 		static char client_requested[SNDRV_SEQ_GLOBAL_CLIENTS];
140 		static char card_requested[SNDRV_CARDS];
141 		if (clientid < SNDRV_SEQ_GLOBAL_CLIENTS) {
142 			int idx;
143 
144 			if (!client_requested[clientid]) {
145 				client_requested[clientid] = 1;
146 				for (idx = 0; idx < 15; idx++) {
147 					if (seq_client_load[idx] < 0)
148 						break;
149 					if (seq_client_load[idx] == clientid) {
150 						request_module("snd-seq-client-%i",
151 							       clientid);
152 						break;
153 					}
154 				}
155 			}
156 		} else if (clientid < SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN) {
157 			int card = (clientid - SNDRV_SEQ_GLOBAL_CLIENTS) /
158 				SNDRV_SEQ_CLIENTS_PER_CARD;
159 			if (card < snd_ecards_limit) {
160 				if (! card_requested[card]) {
161 					card_requested[card] = 1;
162 					snd_request_card(card);
163 				}
164 				snd_seq_device_load_drivers();
165 			}
166 		}
167 		spin_lock_irqsave(&clients_lock, flags);
168 		client = clientptr(clientid);
169 		if (client)
170 			goto __lock;
171 		spin_unlock_irqrestore(&clients_lock, flags);
172 	}
173 #endif
174 	return NULL;
175 
176       __lock:
177 	snd_use_lock_use(&client->use_lock);
178 	spin_unlock_irqrestore(&clients_lock, flags);
179 	return client;
180 }
181 
182 static void usage_alloc(struct snd_seq_usage *res, int num)
183 {
184 	res->cur += num;
185 	if (res->cur > res->peak)
186 		res->peak = res->cur;
187 }
188 
189 static void usage_free(struct snd_seq_usage *res, int num)
190 {
191 	res->cur -= num;
192 }
193 
194 /* initialise data structures */
195 int __init client_init_data(void)
196 {
197 	/* zap out the client table */
198 	memset(&clienttablock, 0, sizeof(clienttablock));
199 	memset(&clienttab, 0, sizeof(clienttab));
200 	return 0;
201 }
202 
203 
204 static struct snd_seq_client *seq_create_client1(int client_index, int poolsize)
205 {
206 	unsigned long flags;
207 	int c;
208 	struct snd_seq_client *client;
209 
210 	/* init client data */
211 	client = kzalloc(sizeof(*client), GFP_KERNEL);
212 	if (client == NULL)
213 		return NULL;
214 	client->pool = snd_seq_pool_new(poolsize);
215 	if (client->pool == NULL) {
216 		kfree(client);
217 		return NULL;
218 	}
219 	client->type = NO_CLIENT;
220 	snd_use_lock_init(&client->use_lock);
221 	rwlock_init(&client->ports_lock);
222 	mutex_init(&client->ports_mutex);
223 	INIT_LIST_HEAD(&client->ports_list_head);
224 	mutex_init(&client->ioctl_mutex);
225 
226 	/* find free slot in the client table */
227 	spin_lock_irqsave(&clients_lock, flags);
228 	if (client_index < 0) {
229 		for (c = SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN;
230 		     c < SNDRV_SEQ_MAX_CLIENTS;
231 		     c++) {
232 			if (clienttab[c] || clienttablock[c])
233 				continue;
234 			clienttab[client->number = c] = client;
235 			spin_unlock_irqrestore(&clients_lock, flags);
236 			return client;
237 		}
238 	} else {
239 		if (clienttab[client_index] == NULL && !clienttablock[client_index]) {
240 			clienttab[client->number = client_index] = client;
241 			spin_unlock_irqrestore(&clients_lock, flags);
242 			return client;
243 		}
244 	}
245 	spin_unlock_irqrestore(&clients_lock, flags);
246 	snd_seq_pool_delete(&client->pool);
247 	kfree(client);
248 	return NULL;	/* no free slot found or busy, return failure code */
249 }
250 
251 
252 static int seq_free_client1(struct snd_seq_client *client)
253 {
254 	unsigned long flags;
255 
256 	if (!client)
257 		return 0;
258 	spin_lock_irqsave(&clients_lock, flags);
259 	clienttablock[client->number] = 1;
260 	clienttab[client->number] = NULL;
261 	spin_unlock_irqrestore(&clients_lock, flags);
262 	snd_seq_delete_all_ports(client);
263 	snd_seq_queue_client_leave(client->number);
264 	snd_use_lock_sync(&client->use_lock);
265 	snd_seq_queue_client_termination(client->number);
266 	if (client->pool)
267 		snd_seq_pool_delete(&client->pool);
268 	spin_lock_irqsave(&clients_lock, flags);
269 	clienttablock[client->number] = 0;
270 	spin_unlock_irqrestore(&clients_lock, flags);
271 	return 0;
272 }
273 
274 
275 static void seq_free_client(struct snd_seq_client * client)
276 {
277 	mutex_lock(&register_mutex);
278 	switch (client->type) {
279 	case NO_CLIENT:
280 		pr_warn("ALSA: seq: Trying to free unused client %d\n",
281 			client->number);
282 		break;
283 	case USER_CLIENT:
284 	case KERNEL_CLIENT:
285 		seq_free_client1(client);
286 		usage_free(&client_usage, 1);
287 		break;
288 
289 	default:
290 		pr_err("ALSA: seq: Trying to free client %d with undefined type = %d\n",
291 			   client->number, client->type);
292 	}
293 	mutex_unlock(&register_mutex);
294 
295 	snd_seq_system_client_ev_client_exit(client->number);
296 }
297 
298 
299 
300 /* -------------------------------------------------------- */
301 
302 /* create a user client */
303 static int snd_seq_open(struct inode *inode, struct file *file)
304 {
305 	int c, mode;			/* client id */
306 	struct snd_seq_client *client;
307 	struct snd_seq_user_client *user;
308 	int err;
309 
310 	err = nonseekable_open(inode, file);
311 	if (err < 0)
312 		return err;
313 
314 	mutex_lock(&register_mutex);
315 	client = seq_create_client1(-1, SNDRV_SEQ_DEFAULT_EVENTS);
316 	if (!client) {
317 		mutex_unlock(&register_mutex);
318 		return -ENOMEM;	/* failure code */
319 	}
320 
321 	mode = snd_seq_file_flags(file);
322 	if (mode & SNDRV_SEQ_LFLG_INPUT)
323 		client->accept_input = 1;
324 	if (mode & SNDRV_SEQ_LFLG_OUTPUT)
325 		client->accept_output = 1;
326 
327 	user = &client->data.user;
328 	user->fifo = NULL;
329 	user->fifo_pool_size = 0;
330 
331 	if (mode & SNDRV_SEQ_LFLG_INPUT) {
332 		user->fifo_pool_size = SNDRV_SEQ_DEFAULT_CLIENT_EVENTS;
333 		user->fifo = snd_seq_fifo_new(user->fifo_pool_size);
334 		if (user->fifo == NULL) {
335 			seq_free_client1(client);
336 			kfree(client);
337 			mutex_unlock(&register_mutex);
338 			return -ENOMEM;
339 		}
340 	}
341 
342 	usage_alloc(&client_usage, 1);
343 	client->type = USER_CLIENT;
344 	mutex_unlock(&register_mutex);
345 
346 	c = client->number;
347 	file->private_data = client;
348 
349 	/* fill client data */
350 	user->file = file;
351 	sprintf(client->name, "Client-%d", c);
352 	client->data.user.owner = get_pid(task_pid(current));
353 
354 	/* make others aware this new client */
355 	snd_seq_system_client_ev_client_start(c);
356 
357 	return 0;
358 }
359 
360 /* delete a user client */
361 static int snd_seq_release(struct inode *inode, struct file *file)
362 {
363 	struct snd_seq_client *client = file->private_data;
364 
365 	if (client) {
366 		seq_free_client(client);
367 		if (client->data.user.fifo)
368 			snd_seq_fifo_delete(&client->data.user.fifo);
369 		put_pid(client->data.user.owner);
370 		kfree(client);
371 	}
372 
373 	return 0;
374 }
375 
376 
377 /* handle client read() */
378 /* possible error values:
379  *	-ENXIO	invalid client or file open mode
380  *	-ENOSPC	FIFO overflow (the flag is cleared after this error report)
381  *	-EINVAL	no enough user-space buffer to write the whole event
382  *	-EFAULT	seg. fault during copy to user space
383  */
384 static ssize_t snd_seq_read(struct file *file, char __user *buf, size_t count,
385 			    loff_t *offset)
386 {
387 	struct snd_seq_client *client = file->private_data;
388 	struct snd_seq_fifo *fifo;
389 	int err;
390 	long result = 0;
391 	struct snd_seq_event_cell *cell;
392 
393 	if (!(snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_INPUT))
394 		return -ENXIO;
395 
396 	if (!access_ok(buf, count))
397 		return -EFAULT;
398 
399 	/* check client structures are in place */
400 	if (snd_BUG_ON(!client))
401 		return -ENXIO;
402 
403 	if (!client->accept_input || (fifo = client->data.user.fifo) == NULL)
404 		return -ENXIO;
405 
406 	if (atomic_read(&fifo->overflow) > 0) {
407 		/* buffer overflow is detected */
408 		snd_seq_fifo_clear(fifo);
409 		/* return error code */
410 		return -ENOSPC;
411 	}
412 
413 	cell = NULL;
414 	err = 0;
415 	snd_seq_fifo_lock(fifo);
416 
417 	/* while data available in queue */
418 	while (count >= sizeof(struct snd_seq_event)) {
419 		int nonblock;
420 
421 		nonblock = (file->f_flags & O_NONBLOCK) || result > 0;
422 		if ((err = snd_seq_fifo_cell_out(fifo, &cell, nonblock)) < 0) {
423 			break;
424 		}
425 		if (snd_seq_ev_is_variable(&cell->event)) {
426 			struct snd_seq_event tmpev;
427 			tmpev = cell->event;
428 			tmpev.data.ext.len &= ~SNDRV_SEQ_EXT_MASK;
429 			if (copy_to_user(buf, &tmpev, sizeof(struct snd_seq_event))) {
430 				err = -EFAULT;
431 				break;
432 			}
433 			count -= sizeof(struct snd_seq_event);
434 			buf += sizeof(struct snd_seq_event);
435 			err = snd_seq_expand_var_event(&cell->event, count,
436 						       (char __force *)buf, 0,
437 						       sizeof(struct snd_seq_event));
438 			if (err < 0)
439 				break;
440 			result += err;
441 			count -= err;
442 			buf += err;
443 		} else {
444 			if (copy_to_user(buf, &cell->event, sizeof(struct snd_seq_event))) {
445 				err = -EFAULT;
446 				break;
447 			}
448 			count -= sizeof(struct snd_seq_event);
449 			buf += sizeof(struct snd_seq_event);
450 		}
451 		snd_seq_cell_free(cell);
452 		cell = NULL; /* to be sure */
453 		result += sizeof(struct snd_seq_event);
454 	}
455 
456 	if (err < 0) {
457 		if (cell)
458 			snd_seq_fifo_cell_putback(fifo, cell);
459 		if (err == -EAGAIN && result > 0)
460 			err = 0;
461 	}
462 	snd_seq_fifo_unlock(fifo);
463 
464 	return (err < 0) ? err : result;
465 }
466 
467 
468 /*
469  * check access permission to the port
470  */
471 static int check_port_perm(struct snd_seq_client_port *port, unsigned int flags)
472 {
473 	if ((port->capability & flags) != flags)
474 		return 0;
475 	return flags;
476 }
477 
478 /*
479  * check if the destination client is available, and return the pointer
480  * if filter is non-zero, client filter bitmap is tested.
481  */
482 static struct snd_seq_client *get_event_dest_client(struct snd_seq_event *event,
483 						    int filter)
484 {
485 	struct snd_seq_client *dest;
486 
487 	dest = snd_seq_client_use_ptr(event->dest.client);
488 	if (dest == NULL)
489 		return NULL;
490 	if (! dest->accept_input)
491 		goto __not_avail;
492 	if ((dest->filter & SNDRV_SEQ_FILTER_USE_EVENT) &&
493 	    ! test_bit(event->type, dest->event_filter))
494 		goto __not_avail;
495 	if (filter && !(dest->filter & filter))
496 		goto __not_avail;
497 
498 	return dest; /* ok - accessible */
499 __not_avail:
500 	snd_seq_client_unlock(dest);
501 	return NULL;
502 }
503 
504 
505 /*
506  * Return the error event.
507  *
508  * If the receiver client is a user client, the original event is
509  * encapsulated in SNDRV_SEQ_EVENT_BOUNCE as variable length event.  If
510  * the original event is also variable length, the external data is
511  * copied after the event record.
512  * If the receiver client is a kernel client, the original event is
513  * quoted in SNDRV_SEQ_EVENT_KERNEL_ERROR, since this requires no extra
514  * kmalloc.
515  */
516 static int bounce_error_event(struct snd_seq_client *client,
517 			      struct snd_seq_event *event,
518 			      int err, int atomic, int hop)
519 {
520 	struct snd_seq_event bounce_ev;
521 	int result;
522 
523 	if (client == NULL ||
524 	    ! (client->filter & SNDRV_SEQ_FILTER_BOUNCE) ||
525 	    ! client->accept_input)
526 		return 0; /* ignored */
527 
528 	/* set up quoted error */
529 	memset(&bounce_ev, 0, sizeof(bounce_ev));
530 	bounce_ev.type = SNDRV_SEQ_EVENT_KERNEL_ERROR;
531 	bounce_ev.flags = SNDRV_SEQ_EVENT_LENGTH_FIXED;
532 	bounce_ev.queue = SNDRV_SEQ_QUEUE_DIRECT;
533 	bounce_ev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
534 	bounce_ev.source.port = SNDRV_SEQ_PORT_SYSTEM_ANNOUNCE;
535 	bounce_ev.dest.client = client->number;
536 	bounce_ev.dest.port = event->source.port;
537 	bounce_ev.data.quote.origin = event->dest;
538 	bounce_ev.data.quote.event = event;
539 	bounce_ev.data.quote.value = -err; /* use positive value */
540 	result = snd_seq_deliver_single_event(NULL, &bounce_ev, 0, atomic, hop + 1);
541 	if (result < 0) {
542 		client->event_lost++;
543 		return result;
544 	}
545 
546 	return result;
547 }
548 
549 
550 /*
551  * rewrite the time-stamp of the event record with the curren time
552  * of the given queue.
553  * return non-zero if updated.
554  */
555 static int update_timestamp_of_queue(struct snd_seq_event *event,
556 				     int queue, int real_time)
557 {
558 	struct snd_seq_queue *q;
559 
560 	q = queueptr(queue);
561 	if (! q)
562 		return 0;
563 	event->queue = queue;
564 	event->flags &= ~SNDRV_SEQ_TIME_STAMP_MASK;
565 	if (real_time) {
566 		event->time.time = snd_seq_timer_get_cur_time(q->timer);
567 		event->flags |= SNDRV_SEQ_TIME_STAMP_REAL;
568 	} else {
569 		event->time.tick = snd_seq_timer_get_cur_tick(q->timer);
570 		event->flags |= SNDRV_SEQ_TIME_STAMP_TICK;
571 	}
572 	queuefree(q);
573 	return 1;
574 }
575 
576 
577 /*
578  * deliver an event to the specified destination.
579  * if filter is non-zero, client filter bitmap is tested.
580  *
581  *  RETURN VALUE: 0 : if succeeded
582  *		 <0 : error
583  */
584 static int snd_seq_deliver_single_event(struct snd_seq_client *client,
585 					struct snd_seq_event *event,
586 					int filter, int atomic, int hop)
587 {
588 	struct snd_seq_client *dest = NULL;
589 	struct snd_seq_client_port *dest_port = NULL;
590 	int result = -ENOENT;
591 	int direct;
592 
593 	direct = snd_seq_ev_is_direct(event);
594 
595 	dest = get_event_dest_client(event, filter);
596 	if (dest == NULL)
597 		goto __skip;
598 	dest_port = snd_seq_port_use_ptr(dest, event->dest.port);
599 	if (dest_port == NULL)
600 		goto __skip;
601 
602 	/* check permission */
603 	if (! check_port_perm(dest_port, SNDRV_SEQ_PORT_CAP_WRITE)) {
604 		result = -EPERM;
605 		goto __skip;
606 	}
607 
608 	if (dest_port->timestamping)
609 		update_timestamp_of_queue(event, dest_port->time_queue,
610 					  dest_port->time_real);
611 
612 	switch (dest->type) {
613 	case USER_CLIENT:
614 		if (dest->data.user.fifo)
615 			result = snd_seq_fifo_event_in(dest->data.user.fifo, event);
616 		break;
617 
618 	case KERNEL_CLIENT:
619 		if (dest_port->event_input == NULL)
620 			break;
621 		result = dest_port->event_input(event, direct,
622 						dest_port->private_data,
623 						atomic, hop);
624 		break;
625 	default:
626 		break;
627 	}
628 
629   __skip:
630 	if (dest_port)
631 		snd_seq_port_unlock(dest_port);
632 	if (dest)
633 		snd_seq_client_unlock(dest);
634 
635 	if (result < 0 && !direct) {
636 		result = bounce_error_event(client, event, result, atomic, hop);
637 	}
638 	return result;
639 }
640 
641 
642 /*
643  * send the event to all subscribers:
644  */
645 static int deliver_to_subscribers(struct snd_seq_client *client,
646 				  struct snd_seq_event *event,
647 				  int atomic, int hop)
648 {
649 	struct snd_seq_subscribers *subs;
650 	int err, result = 0, num_ev = 0;
651 	struct snd_seq_event event_saved;
652 	struct snd_seq_client_port *src_port;
653 	struct snd_seq_port_subs_info *grp;
654 
655 	src_port = snd_seq_port_use_ptr(client, event->source.port);
656 	if (src_port == NULL)
657 		return -EINVAL; /* invalid source port */
658 	/* save original event record */
659 	event_saved = *event;
660 	grp = &src_port->c_src;
661 
662 	/* lock list */
663 	if (atomic)
664 		read_lock(&grp->list_lock);
665 	else
666 		down_read_nested(&grp->list_mutex, hop);
667 	list_for_each_entry(subs, &grp->list_head, src_list) {
668 		/* both ports ready? */
669 		if (atomic_read(&subs->ref_count) != 2)
670 			continue;
671 		event->dest = subs->info.dest;
672 		if (subs->info.flags & SNDRV_SEQ_PORT_SUBS_TIMESTAMP)
673 			/* convert time according to flag with subscription */
674 			update_timestamp_of_queue(event, subs->info.queue,
675 						  subs->info.flags & SNDRV_SEQ_PORT_SUBS_TIME_REAL);
676 		err = snd_seq_deliver_single_event(client, event,
677 						   0, atomic, hop);
678 		if (err < 0) {
679 			/* save first error that occurs and continue */
680 			if (!result)
681 				result = err;
682 			continue;
683 		}
684 		num_ev++;
685 		/* restore original event record */
686 		*event = event_saved;
687 	}
688 	if (atomic)
689 		read_unlock(&grp->list_lock);
690 	else
691 		up_read(&grp->list_mutex);
692 	*event = event_saved; /* restore */
693 	snd_seq_port_unlock(src_port);
694 	return (result < 0) ? result : num_ev;
695 }
696 
697 
698 #ifdef SUPPORT_BROADCAST
699 /*
700  * broadcast to all ports:
701  */
702 static int port_broadcast_event(struct snd_seq_client *client,
703 				struct snd_seq_event *event,
704 				int atomic, int hop)
705 {
706 	int num_ev = 0, err, result = 0;
707 	struct snd_seq_client *dest_client;
708 	struct snd_seq_client_port *port;
709 
710 	dest_client = get_event_dest_client(event, SNDRV_SEQ_FILTER_BROADCAST);
711 	if (dest_client == NULL)
712 		return 0; /* no matching destination */
713 
714 	read_lock(&dest_client->ports_lock);
715 	list_for_each_entry(port, &dest_client->ports_list_head, list) {
716 		event->dest.port = port->addr.port;
717 		/* pass NULL as source client to avoid error bounce */
718 		err = snd_seq_deliver_single_event(NULL, event,
719 						   SNDRV_SEQ_FILTER_BROADCAST,
720 						   atomic, hop);
721 		if (err < 0) {
722 			/* save first error that occurs and continue */
723 			if (!result)
724 				result = err;
725 			continue;
726 		}
727 		num_ev++;
728 	}
729 	read_unlock(&dest_client->ports_lock);
730 	snd_seq_client_unlock(dest_client);
731 	event->dest.port = SNDRV_SEQ_ADDRESS_BROADCAST; /* restore */
732 	return (result < 0) ? result : num_ev;
733 }
734 
735 /*
736  * send the event to all clients:
737  * if destination port is also ADDRESS_BROADCAST, deliver to all ports.
738  */
739 static int broadcast_event(struct snd_seq_client *client,
740 			   struct snd_seq_event *event, int atomic, int hop)
741 {
742 	int err, result = 0, num_ev = 0;
743 	int dest;
744 	struct snd_seq_addr addr;
745 
746 	addr = event->dest; /* save */
747 
748 	for (dest = 0; dest < SNDRV_SEQ_MAX_CLIENTS; dest++) {
749 		/* don't send to itself */
750 		if (dest == client->number)
751 			continue;
752 		event->dest.client = dest;
753 		event->dest.port = addr.port;
754 		if (addr.port == SNDRV_SEQ_ADDRESS_BROADCAST)
755 			err = port_broadcast_event(client, event, atomic, hop);
756 		else
757 			/* pass NULL as source client to avoid error bounce */
758 			err = snd_seq_deliver_single_event(NULL, event,
759 							   SNDRV_SEQ_FILTER_BROADCAST,
760 							   atomic, hop);
761 		if (err < 0) {
762 			/* save first error that occurs and continue */
763 			if (!result)
764 				result = err;
765 			continue;
766 		}
767 		num_ev += err;
768 	}
769 	event->dest = addr; /* restore */
770 	return (result < 0) ? result : num_ev;
771 }
772 
773 
774 /* multicast - not supported yet */
775 static int multicast_event(struct snd_seq_client *client, struct snd_seq_event *event,
776 			   int atomic, int hop)
777 {
778 	pr_debug("ALSA: seq: multicast not supported yet.\n");
779 	return 0; /* ignored */
780 }
781 #endif /* SUPPORT_BROADCAST */
782 
783 
784 /* deliver an event to the destination port(s).
785  * if the event is to subscribers or broadcast, the event is dispatched
786  * to multiple targets.
787  *
788  * RETURN VALUE: n > 0  : the number of delivered events.
789  *               n == 0 : the event was not passed to any client.
790  *               n < 0  : error - event was not processed.
791  */
792 static int snd_seq_deliver_event(struct snd_seq_client *client, struct snd_seq_event *event,
793 				 int atomic, int hop)
794 {
795 	int result;
796 
797 	hop++;
798 	if (hop >= SNDRV_SEQ_MAX_HOPS) {
799 		pr_debug("ALSA: seq: too long delivery path (%d:%d->%d:%d)\n",
800 			   event->source.client, event->source.port,
801 			   event->dest.client, event->dest.port);
802 		return -EMLINK;
803 	}
804 
805 	if (snd_seq_ev_is_variable(event) &&
806 	    snd_BUG_ON(atomic && (event->data.ext.len & SNDRV_SEQ_EXT_USRPTR)))
807 		return -EINVAL;
808 
809 	if (event->queue == SNDRV_SEQ_ADDRESS_SUBSCRIBERS ||
810 	    event->dest.client == SNDRV_SEQ_ADDRESS_SUBSCRIBERS)
811 		result = deliver_to_subscribers(client, event, atomic, hop);
812 #ifdef SUPPORT_BROADCAST
813 	else if (event->queue == SNDRV_SEQ_ADDRESS_BROADCAST ||
814 		 event->dest.client == SNDRV_SEQ_ADDRESS_BROADCAST)
815 		result = broadcast_event(client, event, atomic, hop);
816 	else if (event->dest.client >= SNDRV_SEQ_MAX_CLIENTS)
817 		result = multicast_event(client, event, atomic, hop);
818 	else if (event->dest.port == SNDRV_SEQ_ADDRESS_BROADCAST)
819 		result = port_broadcast_event(client, event, atomic, hop);
820 #endif
821 	else
822 		result = snd_seq_deliver_single_event(client, event, 0, atomic, hop);
823 
824 	return result;
825 }
826 
827 /*
828  * dispatch an event cell:
829  * This function is called only from queue check routines in timer
830  * interrupts or after enqueued.
831  * The event cell shall be released or re-queued in this function.
832  *
833  * RETURN VALUE: n > 0  : the number of delivered events.
834  *		 n == 0 : the event was not passed to any client.
835  *		 n < 0  : error - event was not processed.
836  */
837 int snd_seq_dispatch_event(struct snd_seq_event_cell *cell, int atomic, int hop)
838 {
839 	struct snd_seq_client *client;
840 	int result;
841 
842 	if (snd_BUG_ON(!cell))
843 		return -EINVAL;
844 
845 	client = snd_seq_client_use_ptr(cell->event.source.client);
846 	if (client == NULL) {
847 		snd_seq_cell_free(cell); /* release this cell */
848 		return -EINVAL;
849 	}
850 
851 	if (cell->event.type == SNDRV_SEQ_EVENT_NOTE) {
852 		/* NOTE event:
853 		 * the event cell is re-used as a NOTE-OFF event and
854 		 * enqueued again.
855 		 */
856 		struct snd_seq_event tmpev, *ev;
857 
858 		/* reserve this event to enqueue note-off later */
859 		tmpev = cell->event;
860 		tmpev.type = SNDRV_SEQ_EVENT_NOTEON;
861 		result = snd_seq_deliver_event(client, &tmpev, atomic, hop);
862 
863 		/*
864 		 * This was originally a note event.  We now re-use the
865 		 * cell for the note-off event.
866 		 */
867 
868 		ev = &cell->event;
869 		ev->type = SNDRV_SEQ_EVENT_NOTEOFF;
870 		ev->flags |= SNDRV_SEQ_PRIORITY_HIGH;
871 
872 		/* add the duration time */
873 		switch (ev->flags & SNDRV_SEQ_TIME_STAMP_MASK) {
874 		case SNDRV_SEQ_TIME_STAMP_TICK:
875 			ev->time.tick += ev->data.note.duration;
876 			break;
877 		case SNDRV_SEQ_TIME_STAMP_REAL:
878 			/* unit for duration is ms */
879 			ev->time.time.tv_nsec += 1000000 * (ev->data.note.duration % 1000);
880 			ev->time.time.tv_sec += ev->data.note.duration / 1000 +
881 						ev->time.time.tv_nsec / 1000000000;
882 			ev->time.time.tv_nsec %= 1000000000;
883 			break;
884 		}
885 		ev->data.note.velocity = ev->data.note.off_velocity;
886 
887 		/* Now queue this cell as the note off event */
888 		if (snd_seq_enqueue_event(cell, atomic, hop) < 0)
889 			snd_seq_cell_free(cell); /* release this cell */
890 
891 	} else {
892 		/* Normal events:
893 		 * event cell is freed after processing the event
894 		 */
895 
896 		result = snd_seq_deliver_event(client, &cell->event, atomic, hop);
897 		snd_seq_cell_free(cell);
898 	}
899 
900 	snd_seq_client_unlock(client);
901 	return result;
902 }
903 
904 
905 /* Allocate a cell from client pool and enqueue it to queue:
906  * if pool is empty and blocking is TRUE, sleep until a new cell is
907  * available.
908  */
909 static int snd_seq_client_enqueue_event(struct snd_seq_client *client,
910 					struct snd_seq_event *event,
911 					struct file *file, int blocking,
912 					int atomic, int hop,
913 					struct mutex *mutexp)
914 {
915 	struct snd_seq_event_cell *cell;
916 	int err;
917 
918 	/* special queue values - force direct passing */
919 	if (event->queue == SNDRV_SEQ_ADDRESS_SUBSCRIBERS) {
920 		event->dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
921 		event->queue = SNDRV_SEQ_QUEUE_DIRECT;
922 	} else
923 #ifdef SUPPORT_BROADCAST
924 		if (event->queue == SNDRV_SEQ_ADDRESS_BROADCAST) {
925 			event->dest.client = SNDRV_SEQ_ADDRESS_BROADCAST;
926 			event->queue = SNDRV_SEQ_QUEUE_DIRECT;
927 		}
928 #endif
929 	if (event->dest.client == SNDRV_SEQ_ADDRESS_SUBSCRIBERS) {
930 		/* check presence of source port */
931 		struct snd_seq_client_port *src_port = snd_seq_port_use_ptr(client, event->source.port);
932 		if (src_port == NULL)
933 			return -EINVAL;
934 		snd_seq_port_unlock(src_port);
935 	}
936 
937 	/* direct event processing without enqueued */
938 	if (snd_seq_ev_is_direct(event)) {
939 		if (event->type == SNDRV_SEQ_EVENT_NOTE)
940 			return -EINVAL; /* this event must be enqueued! */
941 		return snd_seq_deliver_event(client, event, atomic, hop);
942 	}
943 
944 	/* Not direct, normal queuing */
945 	if (snd_seq_queue_is_used(event->queue, client->number) <= 0)
946 		return -EINVAL;  /* invalid queue */
947 	if (! snd_seq_write_pool_allocated(client))
948 		return -ENXIO; /* queue is not allocated */
949 
950 	/* allocate an event cell */
951 	err = snd_seq_event_dup(client->pool, event, &cell, !blocking || atomic,
952 				file, mutexp);
953 	if (err < 0)
954 		return err;
955 
956 	/* we got a cell. enqueue it. */
957 	if ((err = snd_seq_enqueue_event(cell, atomic, hop)) < 0) {
958 		snd_seq_cell_free(cell);
959 		return err;
960 	}
961 
962 	return 0;
963 }
964 
965 
966 /*
967  * check validity of event type and data length.
968  * return non-zero if invalid.
969  */
970 static int check_event_type_and_length(struct snd_seq_event *ev)
971 {
972 	switch (snd_seq_ev_length_type(ev)) {
973 	case SNDRV_SEQ_EVENT_LENGTH_FIXED:
974 		if (snd_seq_ev_is_variable_type(ev))
975 			return -EINVAL;
976 		break;
977 	case SNDRV_SEQ_EVENT_LENGTH_VARIABLE:
978 		if (! snd_seq_ev_is_variable_type(ev) ||
979 		    (ev->data.ext.len & ~SNDRV_SEQ_EXT_MASK) >= SNDRV_SEQ_MAX_EVENT_LEN)
980 			return -EINVAL;
981 		break;
982 	case SNDRV_SEQ_EVENT_LENGTH_VARUSR:
983 		if (! snd_seq_ev_is_direct(ev))
984 			return -EINVAL;
985 		break;
986 	}
987 	return 0;
988 }
989 
990 
991 /* handle write() */
992 /* possible error values:
993  *	-ENXIO	invalid client or file open mode
994  *	-ENOMEM	malloc failed
995  *	-EFAULT	seg. fault during copy from user space
996  *	-EINVAL	invalid event
997  *	-EAGAIN	no space in output pool
998  *	-EINTR	interrupts while sleep
999  *	-EMLINK	too many hops
1000  *	others	depends on return value from driver callback
1001  */
1002 static ssize_t snd_seq_write(struct file *file, const char __user *buf,
1003 			     size_t count, loff_t *offset)
1004 {
1005 	struct snd_seq_client *client = file->private_data;
1006 	int written = 0, len;
1007 	int err;
1008 	struct snd_seq_event event;
1009 
1010 	if (!(snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_OUTPUT))
1011 		return -ENXIO;
1012 
1013 	/* check client structures are in place */
1014 	if (snd_BUG_ON(!client))
1015 		return -ENXIO;
1016 
1017 	if (!client->accept_output || client->pool == NULL)
1018 		return -ENXIO;
1019 
1020 	/* allocate the pool now if the pool is not allocated yet */
1021 	mutex_lock(&client->ioctl_mutex);
1022 	if (client->pool->size > 0 && !snd_seq_write_pool_allocated(client)) {
1023 		err = snd_seq_pool_init(client->pool);
1024 		if (err < 0)
1025 			goto out;
1026 	}
1027 
1028 	/* only process whole events */
1029 	err = -EINVAL;
1030 	while (count >= sizeof(struct snd_seq_event)) {
1031 		/* Read in the event header from the user */
1032 		len = sizeof(event);
1033 		if (copy_from_user(&event, buf, len)) {
1034 			err = -EFAULT;
1035 			break;
1036 		}
1037 		event.source.client = client->number;	/* fill in client number */
1038 		/* Check for extension data length */
1039 		if (check_event_type_and_length(&event)) {
1040 			err = -EINVAL;
1041 			break;
1042 		}
1043 
1044 		/* check for special events */
1045 		if (event.type == SNDRV_SEQ_EVENT_NONE)
1046 			goto __skip_event;
1047 		else if (snd_seq_ev_is_reserved(&event)) {
1048 			err = -EINVAL;
1049 			break;
1050 		}
1051 
1052 		if (snd_seq_ev_is_variable(&event)) {
1053 			int extlen = event.data.ext.len & ~SNDRV_SEQ_EXT_MASK;
1054 			if ((size_t)(extlen + len) > count) {
1055 				/* back out, will get an error this time or next */
1056 				err = -EINVAL;
1057 				break;
1058 			}
1059 			/* set user space pointer */
1060 			event.data.ext.len = extlen | SNDRV_SEQ_EXT_USRPTR;
1061 			event.data.ext.ptr = (char __force *)buf
1062 						+ sizeof(struct snd_seq_event);
1063 			len += extlen; /* increment data length */
1064 		} else {
1065 #ifdef CONFIG_COMPAT
1066 			if (client->convert32 && snd_seq_ev_is_varusr(&event)) {
1067 				void *ptr = (void __force *)compat_ptr(event.data.raw32.d[1]);
1068 				event.data.ext.ptr = ptr;
1069 			}
1070 #endif
1071 		}
1072 
1073 		/* ok, enqueue it */
1074 		err = snd_seq_client_enqueue_event(client, &event, file,
1075 						   !(file->f_flags & O_NONBLOCK),
1076 						   0, 0, &client->ioctl_mutex);
1077 		if (err < 0)
1078 			break;
1079 
1080 	__skip_event:
1081 		/* Update pointers and counts */
1082 		count -= len;
1083 		buf += len;
1084 		written += len;
1085 	}
1086 
1087  out:
1088 	mutex_unlock(&client->ioctl_mutex);
1089 	return written ? written : err;
1090 }
1091 
1092 
1093 /*
1094  * handle polling
1095  */
1096 static __poll_t snd_seq_poll(struct file *file, poll_table * wait)
1097 {
1098 	struct snd_seq_client *client = file->private_data;
1099 	__poll_t mask = 0;
1100 
1101 	/* check client structures are in place */
1102 	if (snd_BUG_ON(!client))
1103 		return EPOLLERR;
1104 
1105 	if ((snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_INPUT) &&
1106 	    client->data.user.fifo) {
1107 
1108 		/* check if data is available in the outqueue */
1109 		if (snd_seq_fifo_poll_wait(client->data.user.fifo, file, wait))
1110 			mask |= EPOLLIN | EPOLLRDNORM;
1111 	}
1112 
1113 	if (snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_OUTPUT) {
1114 
1115 		/* check if data is available in the pool */
1116 		if (!snd_seq_write_pool_allocated(client) ||
1117 		    snd_seq_pool_poll_wait(client->pool, file, wait))
1118 			mask |= EPOLLOUT | EPOLLWRNORM;
1119 	}
1120 
1121 	return mask;
1122 }
1123 
1124 
1125 /*-----------------------------------------------------*/
1126 
1127 static int snd_seq_ioctl_pversion(struct snd_seq_client *client, void *arg)
1128 {
1129 	int *pversion = arg;
1130 
1131 	*pversion = SNDRV_SEQ_VERSION;
1132 	return 0;
1133 }
1134 
1135 static int snd_seq_ioctl_client_id(struct snd_seq_client *client, void *arg)
1136 {
1137 	int *client_id = arg;
1138 
1139 	*client_id = client->number;
1140 	return 0;
1141 }
1142 
1143 /* SYSTEM_INFO ioctl() */
1144 static int snd_seq_ioctl_system_info(struct snd_seq_client *client, void *arg)
1145 {
1146 	struct snd_seq_system_info *info = arg;
1147 
1148 	memset(info, 0, sizeof(*info));
1149 	/* fill the info fields */
1150 	info->queues = SNDRV_SEQ_MAX_QUEUES;
1151 	info->clients = SNDRV_SEQ_MAX_CLIENTS;
1152 	info->ports = SNDRV_SEQ_MAX_PORTS;
1153 	info->channels = 256;	/* fixed limit */
1154 	info->cur_clients = client_usage.cur;
1155 	info->cur_queues = snd_seq_queue_get_cur_queues();
1156 
1157 	return 0;
1158 }
1159 
1160 
1161 /* RUNNING_MODE ioctl() */
1162 static int snd_seq_ioctl_running_mode(struct snd_seq_client *client, void  *arg)
1163 {
1164 	struct snd_seq_running_info *info = arg;
1165 	struct snd_seq_client *cptr;
1166 	int err = 0;
1167 
1168 	/* requested client number */
1169 	cptr = snd_seq_client_use_ptr(info->client);
1170 	if (cptr == NULL)
1171 		return -ENOENT;		/* don't change !!! */
1172 
1173 #ifdef SNDRV_BIG_ENDIAN
1174 	if (!info->big_endian) {
1175 		err = -EINVAL;
1176 		goto __err;
1177 	}
1178 #else
1179 	if (info->big_endian) {
1180 		err = -EINVAL;
1181 		goto __err;
1182 	}
1183 
1184 #endif
1185 	if (info->cpu_mode > sizeof(long)) {
1186 		err = -EINVAL;
1187 		goto __err;
1188 	}
1189 	cptr->convert32 = (info->cpu_mode < sizeof(long));
1190  __err:
1191 	snd_seq_client_unlock(cptr);
1192 	return err;
1193 }
1194 
1195 /* CLIENT_INFO ioctl() */
1196 static void get_client_info(struct snd_seq_client *cptr,
1197 			    struct snd_seq_client_info *info)
1198 {
1199 	info->client = cptr->number;
1200 
1201 	/* fill the info fields */
1202 	info->type = cptr->type;
1203 	strcpy(info->name, cptr->name);
1204 	info->filter = cptr->filter;
1205 	info->event_lost = cptr->event_lost;
1206 	memcpy(info->event_filter, cptr->event_filter, 32);
1207 	info->num_ports = cptr->num_ports;
1208 
1209 	if (cptr->type == USER_CLIENT)
1210 		info->pid = pid_vnr(cptr->data.user.owner);
1211 	else
1212 		info->pid = -1;
1213 
1214 	if (cptr->type == KERNEL_CLIENT)
1215 		info->card = cptr->data.kernel.card ? cptr->data.kernel.card->number : -1;
1216 	else
1217 		info->card = -1;
1218 
1219 	memset(info->reserved, 0, sizeof(info->reserved));
1220 }
1221 
1222 static int snd_seq_ioctl_get_client_info(struct snd_seq_client *client,
1223 					 void *arg)
1224 {
1225 	struct snd_seq_client_info *client_info = arg;
1226 	struct snd_seq_client *cptr;
1227 
1228 	/* requested client number */
1229 	cptr = snd_seq_client_use_ptr(client_info->client);
1230 	if (cptr == NULL)
1231 		return -ENOENT;		/* don't change !!! */
1232 
1233 	get_client_info(cptr, client_info);
1234 	snd_seq_client_unlock(cptr);
1235 
1236 	return 0;
1237 }
1238 
1239 
1240 /* CLIENT_INFO ioctl() */
1241 static int snd_seq_ioctl_set_client_info(struct snd_seq_client *client,
1242 					 void *arg)
1243 {
1244 	struct snd_seq_client_info *client_info = arg;
1245 
1246 	/* it is not allowed to set the info fields for an another client */
1247 	if (client->number != client_info->client)
1248 		return -EPERM;
1249 	/* also client type must be set now */
1250 	if (client->type != client_info->type)
1251 		return -EINVAL;
1252 
1253 	/* fill the info fields */
1254 	if (client_info->name[0])
1255 		strscpy(client->name, client_info->name, sizeof(client->name));
1256 
1257 	client->filter = client_info->filter;
1258 	client->event_lost = client_info->event_lost;
1259 	memcpy(client->event_filter, client_info->event_filter, 32);
1260 
1261 	return 0;
1262 }
1263 
1264 
1265 /*
1266  * CREATE PORT ioctl()
1267  */
1268 static int snd_seq_ioctl_create_port(struct snd_seq_client *client, void *arg)
1269 {
1270 	struct snd_seq_port_info *info = arg;
1271 	struct snd_seq_client_port *port;
1272 	struct snd_seq_port_callback *callback;
1273 	int port_idx;
1274 
1275 	/* it is not allowed to create the port for an another client */
1276 	if (info->addr.client != client->number)
1277 		return -EPERM;
1278 
1279 	port = snd_seq_create_port(client, (info->flags & SNDRV_SEQ_PORT_FLG_GIVEN_PORT) ? info->addr.port : -1);
1280 	if (port == NULL)
1281 		return -ENOMEM;
1282 
1283 	if (client->type == USER_CLIENT && info->kernel) {
1284 		port_idx = port->addr.port;
1285 		snd_seq_port_unlock(port);
1286 		snd_seq_delete_port(client, port_idx);
1287 		return -EINVAL;
1288 	}
1289 	if (client->type == KERNEL_CLIENT) {
1290 		if ((callback = info->kernel) != NULL) {
1291 			if (callback->owner)
1292 				port->owner = callback->owner;
1293 			port->private_data = callback->private_data;
1294 			port->private_free = callback->private_free;
1295 			port->event_input = callback->event_input;
1296 			port->c_src.open = callback->subscribe;
1297 			port->c_src.close = callback->unsubscribe;
1298 			port->c_dest.open = callback->use;
1299 			port->c_dest.close = callback->unuse;
1300 		}
1301 	}
1302 
1303 	info->addr = port->addr;
1304 
1305 	snd_seq_set_port_info(port, info);
1306 	snd_seq_system_client_ev_port_start(port->addr.client, port->addr.port);
1307 	snd_seq_port_unlock(port);
1308 
1309 	return 0;
1310 }
1311 
1312 /*
1313  * DELETE PORT ioctl()
1314  */
1315 static int snd_seq_ioctl_delete_port(struct snd_seq_client *client, void *arg)
1316 {
1317 	struct snd_seq_port_info *info = arg;
1318 	int err;
1319 
1320 	/* it is not allowed to remove the port for an another client */
1321 	if (info->addr.client != client->number)
1322 		return -EPERM;
1323 
1324 	err = snd_seq_delete_port(client, info->addr.port);
1325 	if (err >= 0)
1326 		snd_seq_system_client_ev_port_exit(client->number, info->addr.port);
1327 	return err;
1328 }
1329 
1330 
1331 /*
1332  * GET_PORT_INFO ioctl() (on any client)
1333  */
1334 static int snd_seq_ioctl_get_port_info(struct snd_seq_client *client, void *arg)
1335 {
1336 	struct snd_seq_port_info *info = arg;
1337 	struct snd_seq_client *cptr;
1338 	struct snd_seq_client_port *port;
1339 
1340 	cptr = snd_seq_client_use_ptr(info->addr.client);
1341 	if (cptr == NULL)
1342 		return -ENXIO;
1343 
1344 	port = snd_seq_port_use_ptr(cptr, info->addr.port);
1345 	if (port == NULL) {
1346 		snd_seq_client_unlock(cptr);
1347 		return -ENOENT;			/* don't change */
1348 	}
1349 
1350 	/* get port info */
1351 	snd_seq_get_port_info(port, info);
1352 	snd_seq_port_unlock(port);
1353 	snd_seq_client_unlock(cptr);
1354 
1355 	return 0;
1356 }
1357 
1358 
1359 /*
1360  * SET_PORT_INFO ioctl() (only ports on this/own client)
1361  */
1362 static int snd_seq_ioctl_set_port_info(struct snd_seq_client *client, void *arg)
1363 {
1364 	struct snd_seq_port_info *info = arg;
1365 	struct snd_seq_client_port *port;
1366 
1367 	if (info->addr.client != client->number) /* only set our own ports ! */
1368 		return -EPERM;
1369 	port = snd_seq_port_use_ptr(client, info->addr.port);
1370 	if (port) {
1371 		snd_seq_set_port_info(port, info);
1372 		snd_seq_port_unlock(port);
1373 	}
1374 	return 0;
1375 }
1376 
1377 
1378 /*
1379  * port subscription (connection)
1380  */
1381 #define PERM_RD		(SNDRV_SEQ_PORT_CAP_READ|SNDRV_SEQ_PORT_CAP_SUBS_READ)
1382 #define PERM_WR		(SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_SUBS_WRITE)
1383 
1384 static int check_subscription_permission(struct snd_seq_client *client,
1385 					 struct snd_seq_client_port *sport,
1386 					 struct snd_seq_client_port *dport,
1387 					 struct snd_seq_port_subscribe *subs)
1388 {
1389 	if (client->number != subs->sender.client &&
1390 	    client->number != subs->dest.client) {
1391 		/* connection by third client - check export permission */
1392 		if (check_port_perm(sport, SNDRV_SEQ_PORT_CAP_NO_EXPORT))
1393 			return -EPERM;
1394 		if (check_port_perm(dport, SNDRV_SEQ_PORT_CAP_NO_EXPORT))
1395 			return -EPERM;
1396 	}
1397 
1398 	/* check read permission */
1399 	/* if sender or receiver is the subscribing client itself,
1400 	 * no permission check is necessary
1401 	 */
1402 	if (client->number != subs->sender.client) {
1403 		if (! check_port_perm(sport, PERM_RD))
1404 			return -EPERM;
1405 	}
1406 	/* check write permission */
1407 	if (client->number != subs->dest.client) {
1408 		if (! check_port_perm(dport, PERM_WR))
1409 			return -EPERM;
1410 	}
1411 	return 0;
1412 }
1413 
1414 /*
1415  * send an subscription notify event to user client:
1416  * client must be user client.
1417  */
1418 int snd_seq_client_notify_subscription(int client, int port,
1419 				       struct snd_seq_port_subscribe *info,
1420 				       int evtype)
1421 {
1422 	struct snd_seq_event event;
1423 
1424 	memset(&event, 0, sizeof(event));
1425 	event.type = evtype;
1426 	event.data.connect.dest = info->dest;
1427 	event.data.connect.sender = info->sender;
1428 
1429 	return snd_seq_system_notify(client, port, &event);  /* non-atomic */
1430 }
1431 
1432 
1433 /*
1434  * add to port's subscription list IOCTL interface
1435  */
1436 static int snd_seq_ioctl_subscribe_port(struct snd_seq_client *client,
1437 					void *arg)
1438 {
1439 	struct snd_seq_port_subscribe *subs = arg;
1440 	int result = -EINVAL;
1441 	struct snd_seq_client *receiver = NULL, *sender = NULL;
1442 	struct snd_seq_client_port *sport = NULL, *dport = NULL;
1443 
1444 	if ((receiver = snd_seq_client_use_ptr(subs->dest.client)) == NULL)
1445 		goto __end;
1446 	if ((sender = snd_seq_client_use_ptr(subs->sender.client)) == NULL)
1447 		goto __end;
1448 	if ((sport = snd_seq_port_use_ptr(sender, subs->sender.port)) == NULL)
1449 		goto __end;
1450 	if ((dport = snd_seq_port_use_ptr(receiver, subs->dest.port)) == NULL)
1451 		goto __end;
1452 
1453 	result = check_subscription_permission(client, sport, dport, subs);
1454 	if (result < 0)
1455 		goto __end;
1456 
1457 	/* connect them */
1458 	result = snd_seq_port_connect(client, sender, sport, receiver, dport, subs);
1459 	if (! result) /* broadcast announce */
1460 		snd_seq_client_notify_subscription(SNDRV_SEQ_ADDRESS_SUBSCRIBERS, 0,
1461 						   subs, SNDRV_SEQ_EVENT_PORT_SUBSCRIBED);
1462       __end:
1463       	if (sport)
1464 		snd_seq_port_unlock(sport);
1465 	if (dport)
1466 		snd_seq_port_unlock(dport);
1467 	if (sender)
1468 		snd_seq_client_unlock(sender);
1469 	if (receiver)
1470 		snd_seq_client_unlock(receiver);
1471 	return result;
1472 }
1473 
1474 
1475 /*
1476  * remove from port's subscription list
1477  */
1478 static int snd_seq_ioctl_unsubscribe_port(struct snd_seq_client *client,
1479 					  void *arg)
1480 {
1481 	struct snd_seq_port_subscribe *subs = arg;
1482 	int result = -ENXIO;
1483 	struct snd_seq_client *receiver = NULL, *sender = NULL;
1484 	struct snd_seq_client_port *sport = NULL, *dport = NULL;
1485 
1486 	if ((receiver = snd_seq_client_use_ptr(subs->dest.client)) == NULL)
1487 		goto __end;
1488 	if ((sender = snd_seq_client_use_ptr(subs->sender.client)) == NULL)
1489 		goto __end;
1490 	if ((sport = snd_seq_port_use_ptr(sender, subs->sender.port)) == NULL)
1491 		goto __end;
1492 	if ((dport = snd_seq_port_use_ptr(receiver, subs->dest.port)) == NULL)
1493 		goto __end;
1494 
1495 	result = check_subscription_permission(client, sport, dport, subs);
1496 	if (result < 0)
1497 		goto __end;
1498 
1499 	result = snd_seq_port_disconnect(client, sender, sport, receiver, dport, subs);
1500 	if (! result) /* broadcast announce */
1501 		snd_seq_client_notify_subscription(SNDRV_SEQ_ADDRESS_SUBSCRIBERS, 0,
1502 						   subs, SNDRV_SEQ_EVENT_PORT_UNSUBSCRIBED);
1503       __end:
1504       	if (sport)
1505 		snd_seq_port_unlock(sport);
1506 	if (dport)
1507 		snd_seq_port_unlock(dport);
1508 	if (sender)
1509 		snd_seq_client_unlock(sender);
1510 	if (receiver)
1511 		snd_seq_client_unlock(receiver);
1512 	return result;
1513 }
1514 
1515 
1516 /* CREATE_QUEUE ioctl() */
1517 static int snd_seq_ioctl_create_queue(struct snd_seq_client *client, void *arg)
1518 {
1519 	struct snd_seq_queue_info *info = arg;
1520 	struct snd_seq_queue *q;
1521 
1522 	q = snd_seq_queue_alloc(client->number, info->locked, info->flags);
1523 	if (IS_ERR(q))
1524 		return PTR_ERR(q);
1525 
1526 	info->queue = q->queue;
1527 	info->locked = q->locked;
1528 	info->owner = q->owner;
1529 
1530 	/* set queue name */
1531 	if (!info->name[0])
1532 		snprintf(info->name, sizeof(info->name), "Queue-%d", q->queue);
1533 	strscpy(q->name, info->name, sizeof(q->name));
1534 	snd_use_lock_free(&q->use_lock);
1535 
1536 	return 0;
1537 }
1538 
1539 /* DELETE_QUEUE ioctl() */
1540 static int snd_seq_ioctl_delete_queue(struct snd_seq_client *client, void *arg)
1541 {
1542 	struct snd_seq_queue_info *info = arg;
1543 
1544 	return snd_seq_queue_delete(client->number, info->queue);
1545 }
1546 
1547 /* GET_QUEUE_INFO ioctl() */
1548 static int snd_seq_ioctl_get_queue_info(struct snd_seq_client *client,
1549 					void *arg)
1550 {
1551 	struct snd_seq_queue_info *info = arg;
1552 	struct snd_seq_queue *q;
1553 
1554 	q = queueptr(info->queue);
1555 	if (q == NULL)
1556 		return -EINVAL;
1557 
1558 	memset(info, 0, sizeof(*info));
1559 	info->queue = q->queue;
1560 	info->owner = q->owner;
1561 	info->locked = q->locked;
1562 	strlcpy(info->name, q->name, sizeof(info->name));
1563 	queuefree(q);
1564 
1565 	return 0;
1566 }
1567 
1568 /* SET_QUEUE_INFO ioctl() */
1569 static int snd_seq_ioctl_set_queue_info(struct snd_seq_client *client,
1570 					void *arg)
1571 {
1572 	struct snd_seq_queue_info *info = arg;
1573 	struct snd_seq_queue *q;
1574 
1575 	if (info->owner != client->number)
1576 		return -EINVAL;
1577 
1578 	/* change owner/locked permission */
1579 	if (snd_seq_queue_check_access(info->queue, client->number)) {
1580 		if (snd_seq_queue_set_owner(info->queue, client->number, info->locked) < 0)
1581 			return -EPERM;
1582 		if (info->locked)
1583 			snd_seq_queue_use(info->queue, client->number, 1);
1584 	} else {
1585 		return -EPERM;
1586 	}
1587 
1588 	q = queueptr(info->queue);
1589 	if (! q)
1590 		return -EINVAL;
1591 	if (q->owner != client->number) {
1592 		queuefree(q);
1593 		return -EPERM;
1594 	}
1595 	strscpy(q->name, info->name, sizeof(q->name));
1596 	queuefree(q);
1597 
1598 	return 0;
1599 }
1600 
1601 /* GET_NAMED_QUEUE ioctl() */
1602 static int snd_seq_ioctl_get_named_queue(struct snd_seq_client *client,
1603 					 void *arg)
1604 {
1605 	struct snd_seq_queue_info *info = arg;
1606 	struct snd_seq_queue *q;
1607 
1608 	q = snd_seq_queue_find_name(info->name);
1609 	if (q == NULL)
1610 		return -EINVAL;
1611 	info->queue = q->queue;
1612 	info->owner = q->owner;
1613 	info->locked = q->locked;
1614 	queuefree(q);
1615 
1616 	return 0;
1617 }
1618 
1619 /* GET_QUEUE_STATUS ioctl() */
1620 static int snd_seq_ioctl_get_queue_status(struct snd_seq_client *client,
1621 					  void *arg)
1622 {
1623 	struct snd_seq_queue_status *status = arg;
1624 	struct snd_seq_queue *queue;
1625 	struct snd_seq_timer *tmr;
1626 
1627 	queue = queueptr(status->queue);
1628 	if (queue == NULL)
1629 		return -EINVAL;
1630 	memset(status, 0, sizeof(*status));
1631 	status->queue = queue->queue;
1632 
1633 	tmr = queue->timer;
1634 	status->events = queue->tickq->cells + queue->timeq->cells;
1635 
1636 	status->time = snd_seq_timer_get_cur_time(tmr);
1637 	status->tick = snd_seq_timer_get_cur_tick(tmr);
1638 
1639 	status->running = tmr->running;
1640 
1641 	status->flags = queue->flags;
1642 	queuefree(queue);
1643 
1644 	return 0;
1645 }
1646 
1647 
1648 /* GET_QUEUE_TEMPO ioctl() */
1649 static int snd_seq_ioctl_get_queue_tempo(struct snd_seq_client *client,
1650 					 void *arg)
1651 {
1652 	struct snd_seq_queue_tempo *tempo = arg;
1653 	struct snd_seq_queue *queue;
1654 	struct snd_seq_timer *tmr;
1655 
1656 	queue = queueptr(tempo->queue);
1657 	if (queue == NULL)
1658 		return -EINVAL;
1659 	memset(tempo, 0, sizeof(*tempo));
1660 	tempo->queue = queue->queue;
1661 
1662 	tmr = queue->timer;
1663 
1664 	tempo->tempo = tmr->tempo;
1665 	tempo->ppq = tmr->ppq;
1666 	tempo->skew_value = tmr->skew;
1667 	tempo->skew_base = tmr->skew_base;
1668 	queuefree(queue);
1669 
1670 	return 0;
1671 }
1672 
1673 
1674 /* SET_QUEUE_TEMPO ioctl() */
1675 int snd_seq_set_queue_tempo(int client, struct snd_seq_queue_tempo *tempo)
1676 {
1677 	if (!snd_seq_queue_check_access(tempo->queue, client))
1678 		return -EPERM;
1679 	return snd_seq_queue_timer_set_tempo(tempo->queue, client, tempo);
1680 }
1681 EXPORT_SYMBOL(snd_seq_set_queue_tempo);
1682 
1683 static int snd_seq_ioctl_set_queue_tempo(struct snd_seq_client *client,
1684 					 void *arg)
1685 {
1686 	struct snd_seq_queue_tempo *tempo = arg;
1687 	int result;
1688 
1689 	result = snd_seq_set_queue_tempo(client->number, tempo);
1690 	return result < 0 ? result : 0;
1691 }
1692 
1693 
1694 /* GET_QUEUE_TIMER ioctl() */
1695 static int snd_seq_ioctl_get_queue_timer(struct snd_seq_client *client,
1696 					 void *arg)
1697 {
1698 	struct snd_seq_queue_timer *timer = arg;
1699 	struct snd_seq_queue *queue;
1700 	struct snd_seq_timer *tmr;
1701 
1702 	queue = queueptr(timer->queue);
1703 	if (queue == NULL)
1704 		return -EINVAL;
1705 
1706 	mutex_lock(&queue->timer_mutex);
1707 	tmr = queue->timer;
1708 	memset(timer, 0, sizeof(*timer));
1709 	timer->queue = queue->queue;
1710 
1711 	timer->type = tmr->type;
1712 	if (tmr->type == SNDRV_SEQ_TIMER_ALSA) {
1713 		timer->u.alsa.id = tmr->alsa_id;
1714 		timer->u.alsa.resolution = tmr->preferred_resolution;
1715 	}
1716 	mutex_unlock(&queue->timer_mutex);
1717 	queuefree(queue);
1718 
1719 	return 0;
1720 }
1721 
1722 
1723 /* SET_QUEUE_TIMER ioctl() */
1724 static int snd_seq_ioctl_set_queue_timer(struct snd_seq_client *client,
1725 					 void *arg)
1726 {
1727 	struct snd_seq_queue_timer *timer = arg;
1728 	int result = 0;
1729 
1730 	if (timer->type != SNDRV_SEQ_TIMER_ALSA)
1731 		return -EINVAL;
1732 
1733 	if (snd_seq_queue_check_access(timer->queue, client->number)) {
1734 		struct snd_seq_queue *q;
1735 		struct snd_seq_timer *tmr;
1736 
1737 		q = queueptr(timer->queue);
1738 		if (q == NULL)
1739 			return -ENXIO;
1740 		mutex_lock(&q->timer_mutex);
1741 		tmr = q->timer;
1742 		snd_seq_queue_timer_close(timer->queue);
1743 		tmr->type = timer->type;
1744 		if (tmr->type == SNDRV_SEQ_TIMER_ALSA) {
1745 			tmr->alsa_id = timer->u.alsa.id;
1746 			tmr->preferred_resolution = timer->u.alsa.resolution;
1747 		}
1748 		result = snd_seq_queue_timer_open(timer->queue);
1749 		mutex_unlock(&q->timer_mutex);
1750 		queuefree(q);
1751 	} else {
1752 		return -EPERM;
1753 	}
1754 
1755 	return result;
1756 }
1757 
1758 
1759 /* GET_QUEUE_CLIENT ioctl() */
1760 static int snd_seq_ioctl_get_queue_client(struct snd_seq_client *client,
1761 					  void *arg)
1762 {
1763 	struct snd_seq_queue_client *info = arg;
1764 	int used;
1765 
1766 	used = snd_seq_queue_is_used(info->queue, client->number);
1767 	if (used < 0)
1768 		return -EINVAL;
1769 	info->used = used;
1770 	info->client = client->number;
1771 
1772 	return 0;
1773 }
1774 
1775 
1776 /* SET_QUEUE_CLIENT ioctl() */
1777 static int snd_seq_ioctl_set_queue_client(struct snd_seq_client *client,
1778 					  void *arg)
1779 {
1780 	struct snd_seq_queue_client *info = arg;
1781 	int err;
1782 
1783 	if (info->used >= 0) {
1784 		err = snd_seq_queue_use(info->queue, client->number, info->used);
1785 		if (err < 0)
1786 			return err;
1787 	}
1788 
1789 	return snd_seq_ioctl_get_queue_client(client, arg);
1790 }
1791 
1792 
1793 /* GET_CLIENT_POOL ioctl() */
1794 static int snd_seq_ioctl_get_client_pool(struct snd_seq_client *client,
1795 					 void *arg)
1796 {
1797 	struct snd_seq_client_pool *info = arg;
1798 	struct snd_seq_client *cptr;
1799 
1800 	cptr = snd_seq_client_use_ptr(info->client);
1801 	if (cptr == NULL)
1802 		return -ENOENT;
1803 	memset(info, 0, sizeof(*info));
1804 	info->client = cptr->number;
1805 	info->output_pool = cptr->pool->size;
1806 	info->output_room = cptr->pool->room;
1807 	info->output_free = info->output_pool;
1808 	info->output_free = snd_seq_unused_cells(cptr->pool);
1809 	if (cptr->type == USER_CLIENT) {
1810 		info->input_pool = cptr->data.user.fifo_pool_size;
1811 		info->input_free = info->input_pool;
1812 		if (cptr->data.user.fifo)
1813 			info->input_free = snd_seq_unused_cells(cptr->data.user.fifo->pool);
1814 	} else {
1815 		info->input_pool = 0;
1816 		info->input_free = 0;
1817 	}
1818 	snd_seq_client_unlock(cptr);
1819 
1820 	return 0;
1821 }
1822 
1823 /* SET_CLIENT_POOL ioctl() */
1824 static int snd_seq_ioctl_set_client_pool(struct snd_seq_client *client,
1825 					 void *arg)
1826 {
1827 	struct snd_seq_client_pool *info = arg;
1828 	int rc;
1829 
1830 	if (client->number != info->client)
1831 		return -EINVAL; /* can't change other clients */
1832 
1833 	if (info->output_pool >= 1 && info->output_pool <= SNDRV_SEQ_MAX_EVENTS &&
1834 	    (! snd_seq_write_pool_allocated(client) ||
1835 	     info->output_pool != client->pool->size)) {
1836 		if (snd_seq_write_pool_allocated(client)) {
1837 			/* is the pool in use? */
1838 			if (atomic_read(&client->pool->counter))
1839 				return -EBUSY;
1840 			/* remove all existing cells */
1841 			snd_seq_pool_mark_closing(client->pool);
1842 			snd_seq_pool_done(client->pool);
1843 		}
1844 		client->pool->size = info->output_pool;
1845 		rc = snd_seq_pool_init(client->pool);
1846 		if (rc < 0)
1847 			return rc;
1848 	}
1849 	if (client->type == USER_CLIENT && client->data.user.fifo != NULL &&
1850 	    info->input_pool >= 1 &&
1851 	    info->input_pool <= SNDRV_SEQ_MAX_CLIENT_EVENTS &&
1852 	    info->input_pool != client->data.user.fifo_pool_size) {
1853 		/* change pool size */
1854 		rc = snd_seq_fifo_resize(client->data.user.fifo, info->input_pool);
1855 		if (rc < 0)
1856 			return rc;
1857 		client->data.user.fifo_pool_size = info->input_pool;
1858 	}
1859 	if (info->output_room >= 1 &&
1860 	    info->output_room <= client->pool->size) {
1861 		client->pool->room  = info->output_room;
1862 	}
1863 
1864 	return snd_seq_ioctl_get_client_pool(client, arg);
1865 }
1866 
1867 
1868 /* REMOVE_EVENTS ioctl() */
1869 static int snd_seq_ioctl_remove_events(struct snd_seq_client *client,
1870 				       void *arg)
1871 {
1872 	struct snd_seq_remove_events *info = arg;
1873 
1874 	/*
1875 	 * Input mostly not implemented XXX.
1876 	 */
1877 	if (info->remove_mode & SNDRV_SEQ_REMOVE_INPUT) {
1878 		/*
1879 		 * No restrictions so for a user client we can clear
1880 		 * the whole fifo
1881 		 */
1882 		if (client->type == USER_CLIENT && client->data.user.fifo)
1883 			snd_seq_fifo_clear(client->data.user.fifo);
1884 	}
1885 
1886 	if (info->remove_mode & SNDRV_SEQ_REMOVE_OUTPUT)
1887 		snd_seq_queue_remove_cells(client->number, info);
1888 
1889 	return 0;
1890 }
1891 
1892 
1893 /*
1894  * get subscription info
1895  */
1896 static int snd_seq_ioctl_get_subscription(struct snd_seq_client *client,
1897 					  void *arg)
1898 {
1899 	struct snd_seq_port_subscribe *subs = arg;
1900 	int result;
1901 	struct snd_seq_client *sender = NULL;
1902 	struct snd_seq_client_port *sport = NULL;
1903 	struct snd_seq_subscribers *p;
1904 
1905 	result = -EINVAL;
1906 	if ((sender = snd_seq_client_use_ptr(subs->sender.client)) == NULL)
1907 		goto __end;
1908 	if ((sport = snd_seq_port_use_ptr(sender, subs->sender.port)) == NULL)
1909 		goto __end;
1910 	p = snd_seq_port_get_subscription(&sport->c_src, &subs->dest);
1911 	if (p) {
1912 		result = 0;
1913 		*subs = p->info;
1914 	} else
1915 		result = -ENOENT;
1916 
1917       __end:
1918       	if (sport)
1919 		snd_seq_port_unlock(sport);
1920 	if (sender)
1921 		snd_seq_client_unlock(sender);
1922 
1923 	return result;
1924 }
1925 
1926 
1927 /*
1928  * get subscription info - check only its presence
1929  */
1930 static int snd_seq_ioctl_query_subs(struct snd_seq_client *client, void *arg)
1931 {
1932 	struct snd_seq_query_subs *subs = arg;
1933 	int result = -ENXIO;
1934 	struct snd_seq_client *cptr = NULL;
1935 	struct snd_seq_client_port *port = NULL;
1936 	struct snd_seq_port_subs_info *group;
1937 	struct list_head *p;
1938 	int i;
1939 
1940 	if ((cptr = snd_seq_client_use_ptr(subs->root.client)) == NULL)
1941 		goto __end;
1942 	if ((port = snd_seq_port_use_ptr(cptr, subs->root.port)) == NULL)
1943 		goto __end;
1944 
1945 	switch (subs->type) {
1946 	case SNDRV_SEQ_QUERY_SUBS_READ:
1947 		group = &port->c_src;
1948 		break;
1949 	case SNDRV_SEQ_QUERY_SUBS_WRITE:
1950 		group = &port->c_dest;
1951 		break;
1952 	default:
1953 		goto __end;
1954 	}
1955 
1956 	down_read(&group->list_mutex);
1957 	/* search for the subscriber */
1958 	subs->num_subs = group->count;
1959 	i = 0;
1960 	result = -ENOENT;
1961 	list_for_each(p, &group->list_head) {
1962 		if (i++ == subs->index) {
1963 			/* found! */
1964 			struct snd_seq_subscribers *s;
1965 			if (subs->type == SNDRV_SEQ_QUERY_SUBS_READ) {
1966 				s = list_entry(p, struct snd_seq_subscribers, src_list);
1967 				subs->addr = s->info.dest;
1968 			} else {
1969 				s = list_entry(p, struct snd_seq_subscribers, dest_list);
1970 				subs->addr = s->info.sender;
1971 			}
1972 			subs->flags = s->info.flags;
1973 			subs->queue = s->info.queue;
1974 			result = 0;
1975 			break;
1976 		}
1977 	}
1978 	up_read(&group->list_mutex);
1979 
1980       __end:
1981    	if (port)
1982 		snd_seq_port_unlock(port);
1983 	if (cptr)
1984 		snd_seq_client_unlock(cptr);
1985 
1986 	return result;
1987 }
1988 
1989 
1990 /*
1991  * query next client
1992  */
1993 static int snd_seq_ioctl_query_next_client(struct snd_seq_client *client,
1994 					   void *arg)
1995 {
1996 	struct snd_seq_client_info *info = arg;
1997 	struct snd_seq_client *cptr = NULL;
1998 
1999 	/* search for next client */
2000 	if (info->client < INT_MAX)
2001 		info->client++;
2002 	if (info->client < 0)
2003 		info->client = 0;
2004 	for (; info->client < SNDRV_SEQ_MAX_CLIENTS; info->client++) {
2005 		cptr = snd_seq_client_use_ptr(info->client);
2006 		if (cptr)
2007 			break; /* found */
2008 	}
2009 	if (cptr == NULL)
2010 		return -ENOENT;
2011 
2012 	get_client_info(cptr, info);
2013 	snd_seq_client_unlock(cptr);
2014 
2015 	return 0;
2016 }
2017 
2018 /*
2019  * query next port
2020  */
2021 static int snd_seq_ioctl_query_next_port(struct snd_seq_client *client,
2022 					 void *arg)
2023 {
2024 	struct snd_seq_port_info *info = arg;
2025 	struct snd_seq_client *cptr;
2026 	struct snd_seq_client_port *port = NULL;
2027 
2028 	cptr = snd_seq_client_use_ptr(info->addr.client);
2029 	if (cptr == NULL)
2030 		return -ENXIO;
2031 
2032 	/* search for next port */
2033 	info->addr.port++;
2034 	port = snd_seq_port_query_nearest(cptr, info);
2035 	if (port == NULL) {
2036 		snd_seq_client_unlock(cptr);
2037 		return -ENOENT;
2038 	}
2039 
2040 	/* get port info */
2041 	info->addr = port->addr;
2042 	snd_seq_get_port_info(port, info);
2043 	snd_seq_port_unlock(port);
2044 	snd_seq_client_unlock(cptr);
2045 
2046 	return 0;
2047 }
2048 
2049 /* -------------------------------------------------------- */
2050 
2051 static const struct ioctl_handler {
2052 	unsigned int cmd;
2053 	int (*func)(struct snd_seq_client *client, void *arg);
2054 } ioctl_handlers[] = {
2055 	{ SNDRV_SEQ_IOCTL_PVERSION, snd_seq_ioctl_pversion },
2056 	{ SNDRV_SEQ_IOCTL_CLIENT_ID, snd_seq_ioctl_client_id },
2057 	{ SNDRV_SEQ_IOCTL_SYSTEM_INFO, snd_seq_ioctl_system_info },
2058 	{ SNDRV_SEQ_IOCTL_RUNNING_MODE, snd_seq_ioctl_running_mode },
2059 	{ SNDRV_SEQ_IOCTL_GET_CLIENT_INFO, snd_seq_ioctl_get_client_info },
2060 	{ SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, snd_seq_ioctl_set_client_info },
2061 	{ SNDRV_SEQ_IOCTL_CREATE_PORT, snd_seq_ioctl_create_port },
2062 	{ SNDRV_SEQ_IOCTL_DELETE_PORT, snd_seq_ioctl_delete_port },
2063 	{ SNDRV_SEQ_IOCTL_GET_PORT_INFO, snd_seq_ioctl_get_port_info },
2064 	{ SNDRV_SEQ_IOCTL_SET_PORT_INFO, snd_seq_ioctl_set_port_info },
2065 	{ SNDRV_SEQ_IOCTL_SUBSCRIBE_PORT, snd_seq_ioctl_subscribe_port },
2066 	{ SNDRV_SEQ_IOCTL_UNSUBSCRIBE_PORT, snd_seq_ioctl_unsubscribe_port },
2067 	{ SNDRV_SEQ_IOCTL_CREATE_QUEUE, snd_seq_ioctl_create_queue },
2068 	{ SNDRV_SEQ_IOCTL_DELETE_QUEUE, snd_seq_ioctl_delete_queue },
2069 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_INFO, snd_seq_ioctl_get_queue_info },
2070 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_INFO, snd_seq_ioctl_set_queue_info },
2071 	{ SNDRV_SEQ_IOCTL_GET_NAMED_QUEUE, snd_seq_ioctl_get_named_queue },
2072 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_STATUS, snd_seq_ioctl_get_queue_status },
2073 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_TEMPO, snd_seq_ioctl_get_queue_tempo },
2074 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_TEMPO, snd_seq_ioctl_set_queue_tempo },
2075 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_TIMER, snd_seq_ioctl_get_queue_timer },
2076 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_TIMER, snd_seq_ioctl_set_queue_timer },
2077 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_CLIENT, snd_seq_ioctl_get_queue_client },
2078 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_CLIENT, snd_seq_ioctl_set_queue_client },
2079 	{ SNDRV_SEQ_IOCTL_GET_CLIENT_POOL, snd_seq_ioctl_get_client_pool },
2080 	{ SNDRV_SEQ_IOCTL_SET_CLIENT_POOL, snd_seq_ioctl_set_client_pool },
2081 	{ SNDRV_SEQ_IOCTL_GET_SUBSCRIPTION, snd_seq_ioctl_get_subscription },
2082 	{ SNDRV_SEQ_IOCTL_QUERY_NEXT_CLIENT, snd_seq_ioctl_query_next_client },
2083 	{ SNDRV_SEQ_IOCTL_QUERY_NEXT_PORT, snd_seq_ioctl_query_next_port },
2084 	{ SNDRV_SEQ_IOCTL_REMOVE_EVENTS, snd_seq_ioctl_remove_events },
2085 	{ SNDRV_SEQ_IOCTL_QUERY_SUBS, snd_seq_ioctl_query_subs },
2086 	{ 0, NULL },
2087 };
2088 
2089 static long snd_seq_ioctl(struct file *file, unsigned int cmd,
2090 			  unsigned long arg)
2091 {
2092 	struct snd_seq_client *client = file->private_data;
2093 	/* To use kernel stack for ioctl data. */
2094 	union {
2095 		int pversion;
2096 		int client_id;
2097 		struct snd_seq_system_info	system_info;
2098 		struct snd_seq_running_info	running_info;
2099 		struct snd_seq_client_info	client_info;
2100 		struct snd_seq_port_info	port_info;
2101 		struct snd_seq_port_subscribe	port_subscribe;
2102 		struct snd_seq_queue_info	queue_info;
2103 		struct snd_seq_queue_status	queue_status;
2104 		struct snd_seq_queue_tempo	tempo;
2105 		struct snd_seq_queue_timer	queue_timer;
2106 		struct snd_seq_queue_client	queue_client;
2107 		struct snd_seq_client_pool	client_pool;
2108 		struct snd_seq_remove_events	remove_events;
2109 		struct snd_seq_query_subs	query_subs;
2110 	} buf;
2111 	const struct ioctl_handler *handler;
2112 	unsigned long size;
2113 	int err;
2114 
2115 	if (snd_BUG_ON(!client))
2116 		return -ENXIO;
2117 
2118 	for (handler = ioctl_handlers; handler->cmd > 0; ++handler) {
2119 		if (handler->cmd == cmd)
2120 			break;
2121 	}
2122 	if (handler->cmd == 0)
2123 		return -ENOTTY;
2124 
2125 	memset(&buf, 0, sizeof(buf));
2126 
2127 	/*
2128 	 * All of ioctl commands for ALSA sequencer get an argument of size
2129 	 * within 13 bits. We can safely pick up the size from the command.
2130 	 */
2131 	size = _IOC_SIZE(handler->cmd);
2132 	if (handler->cmd & IOC_IN) {
2133 		if (copy_from_user(&buf, (const void __user *)arg, size))
2134 			return -EFAULT;
2135 	}
2136 
2137 	mutex_lock(&client->ioctl_mutex);
2138 	err = handler->func(client, &buf);
2139 	mutex_unlock(&client->ioctl_mutex);
2140 	if (err >= 0) {
2141 		/* Some commands includes a bug in 'dir' field. */
2142 		if (handler->cmd == SNDRV_SEQ_IOCTL_SET_QUEUE_CLIENT ||
2143 		    handler->cmd == SNDRV_SEQ_IOCTL_SET_CLIENT_POOL ||
2144 		    (handler->cmd & IOC_OUT))
2145 			if (copy_to_user((void __user *)arg, &buf, size))
2146 				return -EFAULT;
2147 	}
2148 
2149 	return err;
2150 }
2151 
2152 #ifdef CONFIG_COMPAT
2153 #include "seq_compat.c"
2154 #else
2155 #define snd_seq_ioctl_compat	NULL
2156 #endif
2157 
2158 /* -------------------------------------------------------- */
2159 
2160 
2161 /* exported to kernel modules */
2162 int snd_seq_create_kernel_client(struct snd_card *card, int client_index,
2163 				 const char *name_fmt, ...)
2164 {
2165 	struct snd_seq_client *client;
2166 	va_list args;
2167 
2168 	if (snd_BUG_ON(in_interrupt()))
2169 		return -EBUSY;
2170 
2171 	if (card && client_index >= SNDRV_SEQ_CLIENTS_PER_CARD)
2172 		return -EINVAL;
2173 	if (card == NULL && client_index >= SNDRV_SEQ_GLOBAL_CLIENTS)
2174 		return -EINVAL;
2175 
2176 	mutex_lock(&register_mutex);
2177 
2178 	if (card) {
2179 		client_index += SNDRV_SEQ_GLOBAL_CLIENTS
2180 			+ card->number * SNDRV_SEQ_CLIENTS_PER_CARD;
2181 		if (client_index >= SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN)
2182 			client_index = -1;
2183 	}
2184 
2185 	/* empty write queue as default */
2186 	client = seq_create_client1(client_index, 0);
2187 	if (client == NULL) {
2188 		mutex_unlock(&register_mutex);
2189 		return -EBUSY;	/* failure code */
2190 	}
2191 	usage_alloc(&client_usage, 1);
2192 
2193 	client->accept_input = 1;
2194 	client->accept_output = 1;
2195 	client->data.kernel.card = card;
2196 
2197 	va_start(args, name_fmt);
2198 	vsnprintf(client->name, sizeof(client->name), name_fmt, args);
2199 	va_end(args);
2200 
2201 	client->type = KERNEL_CLIENT;
2202 	mutex_unlock(&register_mutex);
2203 
2204 	/* make others aware this new client */
2205 	snd_seq_system_client_ev_client_start(client->number);
2206 
2207 	/* return client number to caller */
2208 	return client->number;
2209 }
2210 EXPORT_SYMBOL(snd_seq_create_kernel_client);
2211 
2212 /* exported to kernel modules */
2213 int snd_seq_delete_kernel_client(int client)
2214 {
2215 	struct snd_seq_client *ptr;
2216 
2217 	if (snd_BUG_ON(in_interrupt()))
2218 		return -EBUSY;
2219 
2220 	ptr = clientptr(client);
2221 	if (ptr == NULL)
2222 		return -EINVAL;
2223 
2224 	seq_free_client(ptr);
2225 	kfree(ptr);
2226 	return 0;
2227 }
2228 EXPORT_SYMBOL(snd_seq_delete_kernel_client);
2229 
2230 /* skeleton to enqueue event, called from snd_seq_kernel_client_enqueue
2231  * and snd_seq_kernel_client_enqueue_blocking
2232  */
2233 static int kernel_client_enqueue(int client, struct snd_seq_event *ev,
2234 				 struct file *file, int blocking,
2235 				 int atomic, int hop)
2236 {
2237 	struct snd_seq_client *cptr;
2238 	int result;
2239 
2240 	if (snd_BUG_ON(!ev))
2241 		return -EINVAL;
2242 
2243 	if (ev->type == SNDRV_SEQ_EVENT_NONE)
2244 		return 0; /* ignore this */
2245 	if (ev->type == SNDRV_SEQ_EVENT_KERNEL_ERROR)
2246 		return -EINVAL; /* quoted events can't be enqueued */
2247 
2248 	/* fill in client number */
2249 	ev->source.client = client;
2250 
2251 	if (check_event_type_and_length(ev))
2252 		return -EINVAL;
2253 
2254 	cptr = snd_seq_client_use_ptr(client);
2255 	if (cptr == NULL)
2256 		return -EINVAL;
2257 
2258 	if (! cptr->accept_output)
2259 		result = -EPERM;
2260 	else /* send it */
2261 		result = snd_seq_client_enqueue_event(cptr, ev, file, blocking,
2262 						      atomic, hop, NULL);
2263 
2264 	snd_seq_client_unlock(cptr);
2265 	return result;
2266 }
2267 
2268 /*
2269  * exported, called by kernel clients to enqueue events (w/o blocking)
2270  *
2271  * RETURN VALUE: zero if succeed, negative if error
2272  */
2273 int snd_seq_kernel_client_enqueue(int client, struct snd_seq_event * ev,
2274 				  int atomic, int hop)
2275 {
2276 	return kernel_client_enqueue(client, ev, NULL, 0, atomic, hop);
2277 }
2278 EXPORT_SYMBOL(snd_seq_kernel_client_enqueue);
2279 
2280 /*
2281  * exported, called by kernel clients to enqueue events (with blocking)
2282  *
2283  * RETURN VALUE: zero if succeed, negative if error
2284  */
2285 int snd_seq_kernel_client_enqueue_blocking(int client, struct snd_seq_event * ev,
2286 					   struct file *file,
2287 					   int atomic, int hop)
2288 {
2289 	return kernel_client_enqueue(client, ev, file, 1, atomic, hop);
2290 }
2291 EXPORT_SYMBOL(snd_seq_kernel_client_enqueue_blocking);
2292 
2293 /*
2294  * exported, called by kernel clients to dispatch events directly to other
2295  * clients, bypassing the queues.  Event time-stamp will be updated.
2296  *
2297  * RETURN VALUE: negative = delivery failed,
2298  *		 zero, or positive: the number of delivered events
2299  */
2300 int snd_seq_kernel_client_dispatch(int client, struct snd_seq_event * ev,
2301 				   int atomic, int hop)
2302 {
2303 	struct snd_seq_client *cptr;
2304 	int result;
2305 
2306 	if (snd_BUG_ON(!ev))
2307 		return -EINVAL;
2308 
2309 	/* fill in client number */
2310 	ev->queue = SNDRV_SEQ_QUEUE_DIRECT;
2311 	ev->source.client = client;
2312 
2313 	if (check_event_type_and_length(ev))
2314 		return -EINVAL;
2315 
2316 	cptr = snd_seq_client_use_ptr(client);
2317 	if (cptr == NULL)
2318 		return -EINVAL;
2319 
2320 	if (!cptr->accept_output)
2321 		result = -EPERM;
2322 	else
2323 		result = snd_seq_deliver_event(cptr, ev, atomic, hop);
2324 
2325 	snd_seq_client_unlock(cptr);
2326 	return result;
2327 }
2328 EXPORT_SYMBOL(snd_seq_kernel_client_dispatch);
2329 
2330 /**
2331  * snd_seq_kernel_client_ctl - operate a command for a client with data in
2332  *			       kernel space.
2333  * @clientid:	A numerical ID for a client.
2334  * @cmd:	An ioctl(2) command for ALSA sequencer operation.
2335  * @arg:	A pointer to data in kernel space.
2336  *
2337  * Against its name, both kernel/application client can be handled by this
2338  * kernel API. A pointer of 'arg' argument should be in kernel space.
2339  *
2340  * Return: 0 at success. Negative error code at failure.
2341  */
2342 int snd_seq_kernel_client_ctl(int clientid, unsigned int cmd, void *arg)
2343 {
2344 	const struct ioctl_handler *handler;
2345 	struct snd_seq_client *client;
2346 
2347 	client = clientptr(clientid);
2348 	if (client == NULL)
2349 		return -ENXIO;
2350 
2351 	for (handler = ioctl_handlers; handler->cmd > 0; ++handler) {
2352 		if (handler->cmd == cmd)
2353 			return handler->func(client, arg);
2354 	}
2355 
2356 	pr_debug("ALSA: seq unknown ioctl() 0x%x (type='%c', number=0x%02x)\n",
2357 		 cmd, _IOC_TYPE(cmd), _IOC_NR(cmd));
2358 	return -ENOTTY;
2359 }
2360 EXPORT_SYMBOL(snd_seq_kernel_client_ctl);
2361 
2362 /* exported (for OSS emulator) */
2363 int snd_seq_kernel_client_write_poll(int clientid, struct file *file, poll_table *wait)
2364 {
2365 	struct snd_seq_client *client;
2366 
2367 	client = clientptr(clientid);
2368 	if (client == NULL)
2369 		return -ENXIO;
2370 
2371 	if (! snd_seq_write_pool_allocated(client))
2372 		return 1;
2373 	if (snd_seq_pool_poll_wait(client->pool, file, wait))
2374 		return 1;
2375 	return 0;
2376 }
2377 EXPORT_SYMBOL(snd_seq_kernel_client_write_poll);
2378 
2379 /*---------------------------------------------------------------------------*/
2380 
2381 #ifdef CONFIG_SND_PROC_FS
2382 /*
2383  *  /proc interface
2384  */
2385 static void snd_seq_info_dump_subscribers(struct snd_info_buffer *buffer,
2386 					  struct snd_seq_port_subs_info *group,
2387 					  int is_src, char *msg)
2388 {
2389 	struct list_head *p;
2390 	struct snd_seq_subscribers *s;
2391 	int count = 0;
2392 
2393 	down_read(&group->list_mutex);
2394 	if (list_empty(&group->list_head)) {
2395 		up_read(&group->list_mutex);
2396 		return;
2397 	}
2398 	snd_iprintf(buffer, msg);
2399 	list_for_each(p, &group->list_head) {
2400 		if (is_src)
2401 			s = list_entry(p, struct snd_seq_subscribers, src_list);
2402 		else
2403 			s = list_entry(p, struct snd_seq_subscribers, dest_list);
2404 		if (count++)
2405 			snd_iprintf(buffer, ", ");
2406 		snd_iprintf(buffer, "%d:%d",
2407 			    is_src ? s->info.dest.client : s->info.sender.client,
2408 			    is_src ? s->info.dest.port : s->info.sender.port);
2409 		if (s->info.flags & SNDRV_SEQ_PORT_SUBS_TIMESTAMP)
2410 			snd_iprintf(buffer, "[%c:%d]", ((s->info.flags & SNDRV_SEQ_PORT_SUBS_TIME_REAL) ? 'r' : 't'), s->info.queue);
2411 		if (group->exclusive)
2412 			snd_iprintf(buffer, "[ex]");
2413 	}
2414 	up_read(&group->list_mutex);
2415 	snd_iprintf(buffer, "\n");
2416 }
2417 
2418 #define FLAG_PERM_RD(perm) ((perm) & SNDRV_SEQ_PORT_CAP_READ ? ((perm) & SNDRV_SEQ_PORT_CAP_SUBS_READ ? 'R' : 'r') : '-')
2419 #define FLAG_PERM_WR(perm) ((perm) & SNDRV_SEQ_PORT_CAP_WRITE ? ((perm) & SNDRV_SEQ_PORT_CAP_SUBS_WRITE ? 'W' : 'w') : '-')
2420 #define FLAG_PERM_EX(perm) ((perm) & SNDRV_SEQ_PORT_CAP_NO_EXPORT ? '-' : 'e')
2421 
2422 #define FLAG_PERM_DUPLEX(perm) ((perm) & SNDRV_SEQ_PORT_CAP_DUPLEX ? 'X' : '-')
2423 
2424 static void snd_seq_info_dump_ports(struct snd_info_buffer *buffer,
2425 				    struct snd_seq_client *client)
2426 {
2427 	struct snd_seq_client_port *p;
2428 
2429 	mutex_lock(&client->ports_mutex);
2430 	list_for_each_entry(p, &client->ports_list_head, list) {
2431 		snd_iprintf(buffer, "  Port %3d : \"%s\" (%c%c%c%c)\n",
2432 			    p->addr.port, p->name,
2433 			    FLAG_PERM_RD(p->capability),
2434 			    FLAG_PERM_WR(p->capability),
2435 			    FLAG_PERM_EX(p->capability),
2436 			    FLAG_PERM_DUPLEX(p->capability));
2437 		snd_seq_info_dump_subscribers(buffer, &p->c_src, 1, "    Connecting To: ");
2438 		snd_seq_info_dump_subscribers(buffer, &p->c_dest, 0, "    Connected From: ");
2439 	}
2440 	mutex_unlock(&client->ports_mutex);
2441 }
2442 
2443 
2444 /* exported to seq_info.c */
2445 void snd_seq_info_clients_read(struct snd_info_entry *entry,
2446 			       struct snd_info_buffer *buffer)
2447 {
2448 	int c;
2449 	struct snd_seq_client *client;
2450 
2451 	snd_iprintf(buffer, "Client info\n");
2452 	snd_iprintf(buffer, "  cur  clients : %d\n", client_usage.cur);
2453 	snd_iprintf(buffer, "  peak clients : %d\n", client_usage.peak);
2454 	snd_iprintf(buffer, "  max  clients : %d\n", SNDRV_SEQ_MAX_CLIENTS);
2455 	snd_iprintf(buffer, "\n");
2456 
2457 	/* list the client table */
2458 	for (c = 0; c < SNDRV_SEQ_MAX_CLIENTS; c++) {
2459 		client = snd_seq_client_use_ptr(c);
2460 		if (client == NULL)
2461 			continue;
2462 		if (client->type == NO_CLIENT) {
2463 			snd_seq_client_unlock(client);
2464 			continue;
2465 		}
2466 
2467 		snd_iprintf(buffer, "Client %3d : \"%s\" [%s]\n",
2468 			    c, client->name,
2469 			    client->type == USER_CLIENT ? "User" : "Kernel");
2470 		snd_seq_info_dump_ports(buffer, client);
2471 		if (snd_seq_write_pool_allocated(client)) {
2472 			snd_iprintf(buffer, "  Output pool :\n");
2473 			snd_seq_info_pool(buffer, client->pool, "    ");
2474 		}
2475 		if (client->type == USER_CLIENT && client->data.user.fifo &&
2476 		    client->data.user.fifo->pool) {
2477 			snd_iprintf(buffer, "  Input pool :\n");
2478 			snd_seq_info_pool(buffer, client->data.user.fifo->pool, "    ");
2479 		}
2480 		snd_seq_client_unlock(client);
2481 	}
2482 }
2483 #endif /* CONFIG_SND_PROC_FS */
2484 
2485 /*---------------------------------------------------------------------------*/
2486 
2487 
2488 /*
2489  *  REGISTRATION PART
2490  */
2491 
2492 static const struct file_operations snd_seq_f_ops =
2493 {
2494 	.owner =	THIS_MODULE,
2495 	.read =		snd_seq_read,
2496 	.write =	snd_seq_write,
2497 	.open =		snd_seq_open,
2498 	.release =	snd_seq_release,
2499 	.llseek =	no_llseek,
2500 	.poll =		snd_seq_poll,
2501 	.unlocked_ioctl =	snd_seq_ioctl,
2502 	.compat_ioctl =	snd_seq_ioctl_compat,
2503 };
2504 
2505 static struct device seq_dev;
2506 
2507 /*
2508  * register sequencer device
2509  */
2510 int __init snd_sequencer_device_init(void)
2511 {
2512 	int err;
2513 
2514 	snd_device_initialize(&seq_dev, NULL);
2515 	dev_set_name(&seq_dev, "seq");
2516 
2517 	mutex_lock(&register_mutex);
2518 	err = snd_register_device(SNDRV_DEVICE_TYPE_SEQUENCER, NULL, 0,
2519 				  &snd_seq_f_ops, NULL, &seq_dev);
2520 	mutex_unlock(&register_mutex);
2521 	if (err < 0) {
2522 		put_device(&seq_dev);
2523 		return err;
2524 	}
2525 
2526 	return 0;
2527 }
2528 
2529 
2530 
2531 /*
2532  * unregister sequencer device
2533  */
2534 void snd_sequencer_device_done(void)
2535 {
2536 	snd_unregister_device(&seq_dev);
2537 	put_device(&seq_dev);
2538 }
2539