xref: /openbmc/linux/sound/core/seq/seq_clientmgr.c (revision 8730046c)
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 
225 	/* find free slot in the client table */
226 	spin_lock_irqsave(&clients_lock, flags);
227 	if (client_index < 0) {
228 		for (c = SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN;
229 		     c < SNDRV_SEQ_MAX_CLIENTS;
230 		     c++) {
231 			if (clienttab[c] || clienttablock[c])
232 				continue;
233 			clienttab[client->number = c] = client;
234 			spin_unlock_irqrestore(&clients_lock, flags);
235 			return client;
236 		}
237 	} else {
238 		if (clienttab[client_index] == NULL && !clienttablock[client_index]) {
239 			clienttab[client->number = client_index] = client;
240 			spin_unlock_irqrestore(&clients_lock, flags);
241 			return client;
242 		}
243 	}
244 	spin_unlock_irqrestore(&clients_lock, flags);
245 	snd_seq_pool_delete(&client->pool);
246 	kfree(client);
247 	return NULL;	/* no free slot found or busy, return failure code */
248 }
249 
250 
251 static int seq_free_client1(struct snd_seq_client *client)
252 {
253 	unsigned long flags;
254 
255 	if (!client)
256 		return 0;
257 	snd_seq_delete_all_ports(client);
258 	snd_seq_queue_client_leave(client->number);
259 	spin_lock_irqsave(&clients_lock, flags);
260 	clienttablock[client->number] = 1;
261 	clienttab[client->number] = NULL;
262 	spin_unlock_irqrestore(&clients_lock, flags);
263 	snd_use_lock_sync(&client->use_lock);
264 	snd_seq_queue_client_termination(client->number);
265 	if (client->pool)
266 		snd_seq_pool_delete(&client->pool);
267 	spin_lock_irqsave(&clients_lock, flags);
268 	clienttablock[client->number] = 0;
269 	spin_unlock_irqrestore(&clients_lock, flags);
270 	return 0;
271 }
272 
273 
274 static void seq_free_client(struct snd_seq_client * client)
275 {
276 	mutex_lock(&register_mutex);
277 	switch (client->type) {
278 	case NO_CLIENT:
279 		pr_warn("ALSA: seq: Trying to free unused client %d\n",
280 			client->number);
281 		break;
282 	case USER_CLIENT:
283 	case KERNEL_CLIENT:
284 		seq_free_client1(client);
285 		usage_free(&client_usage, 1);
286 		break;
287 
288 	default:
289 		pr_err("ALSA: seq: Trying to free client %d with undefined type = %d\n",
290 			   client->number, client->type);
291 	}
292 	mutex_unlock(&register_mutex);
293 
294 	snd_seq_system_client_ev_client_exit(client->number);
295 }
296 
297 
298 
299 /* -------------------------------------------------------- */
300 
301 /* create a user client */
302 static int snd_seq_open(struct inode *inode, struct file *file)
303 {
304 	int c, mode;			/* client id */
305 	struct snd_seq_client *client;
306 	struct snd_seq_user_client *user;
307 	int err;
308 
309 	err = nonseekable_open(inode, file);
310 	if (err < 0)
311 		return err;
312 
313 	if (mutex_lock_interruptible(&register_mutex))
314 		return -ERESTARTSYS;
315 	client = seq_create_client1(-1, SNDRV_SEQ_DEFAULT_EVENTS);
316 	if (client == NULL) {
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(VERIFY_WRITE, 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(&grp->list_mutex);
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 (event->queue == SNDRV_SEQ_ADDRESS_SUBSCRIBERS ||
806 	    event->dest.client == SNDRV_SEQ_ADDRESS_SUBSCRIBERS)
807 		result = deliver_to_subscribers(client, event, atomic, hop);
808 #ifdef SUPPORT_BROADCAST
809 	else if (event->queue == SNDRV_SEQ_ADDRESS_BROADCAST ||
810 		 event->dest.client == SNDRV_SEQ_ADDRESS_BROADCAST)
811 		result = broadcast_event(client, event, atomic, hop);
812 	else if (event->dest.client >= SNDRV_SEQ_MAX_CLIENTS)
813 		result = multicast_event(client, event, atomic, hop);
814 	else if (event->dest.port == SNDRV_SEQ_ADDRESS_BROADCAST)
815 		result = port_broadcast_event(client, event, atomic, hop);
816 #endif
817 	else
818 		result = snd_seq_deliver_single_event(client, event, 0, atomic, hop);
819 
820 	return result;
821 }
822 
823 /*
824  * dispatch an event cell:
825  * This function is called only from queue check routines in timer
826  * interrupts or after enqueued.
827  * The event cell shall be released or re-queued in this function.
828  *
829  * RETURN VALUE: n > 0  : the number of delivered events.
830  *		 n == 0 : the event was not passed to any client.
831  *		 n < 0  : error - event was not processed.
832  */
833 int snd_seq_dispatch_event(struct snd_seq_event_cell *cell, int atomic, int hop)
834 {
835 	struct snd_seq_client *client;
836 	int result;
837 
838 	if (snd_BUG_ON(!cell))
839 		return -EINVAL;
840 
841 	client = snd_seq_client_use_ptr(cell->event.source.client);
842 	if (client == NULL) {
843 		snd_seq_cell_free(cell); /* release this cell */
844 		return -EINVAL;
845 	}
846 
847 	if (cell->event.type == SNDRV_SEQ_EVENT_NOTE) {
848 		/* NOTE event:
849 		 * the event cell is re-used as a NOTE-OFF event and
850 		 * enqueued again.
851 		 */
852 		struct snd_seq_event tmpev, *ev;
853 
854 		/* reserve this event to enqueue note-off later */
855 		tmpev = cell->event;
856 		tmpev.type = SNDRV_SEQ_EVENT_NOTEON;
857 		result = snd_seq_deliver_event(client, &tmpev, atomic, hop);
858 
859 		/*
860 		 * This was originally a note event.  We now re-use the
861 		 * cell for the note-off event.
862 		 */
863 
864 		ev = &cell->event;
865 		ev->type = SNDRV_SEQ_EVENT_NOTEOFF;
866 		ev->flags |= SNDRV_SEQ_PRIORITY_HIGH;
867 
868 		/* add the duration time */
869 		switch (ev->flags & SNDRV_SEQ_TIME_STAMP_MASK) {
870 		case SNDRV_SEQ_TIME_STAMP_TICK:
871 			ev->time.tick += ev->data.note.duration;
872 			break;
873 		case SNDRV_SEQ_TIME_STAMP_REAL:
874 			/* unit for duration is ms */
875 			ev->time.time.tv_nsec += 1000000 * (ev->data.note.duration % 1000);
876 			ev->time.time.tv_sec += ev->data.note.duration / 1000 +
877 						ev->time.time.tv_nsec / 1000000000;
878 			ev->time.time.tv_nsec %= 1000000000;
879 			break;
880 		}
881 		ev->data.note.velocity = ev->data.note.off_velocity;
882 
883 		/* Now queue this cell as the note off event */
884 		if (snd_seq_enqueue_event(cell, atomic, hop) < 0)
885 			snd_seq_cell_free(cell); /* release this cell */
886 
887 	} else {
888 		/* Normal events:
889 		 * event cell is freed after processing the event
890 		 */
891 
892 		result = snd_seq_deliver_event(client, &cell->event, atomic, hop);
893 		snd_seq_cell_free(cell);
894 	}
895 
896 	snd_seq_client_unlock(client);
897 	return result;
898 }
899 
900 
901 /* Allocate a cell from client pool and enqueue it to queue:
902  * if pool is empty and blocking is TRUE, sleep until a new cell is
903  * available.
904  */
905 static int snd_seq_client_enqueue_event(struct snd_seq_client *client,
906 					struct snd_seq_event *event,
907 					struct file *file, int blocking,
908 					int atomic, int hop)
909 {
910 	struct snd_seq_event_cell *cell;
911 	int err;
912 
913 	/* special queue values - force direct passing */
914 	if (event->queue == SNDRV_SEQ_ADDRESS_SUBSCRIBERS) {
915 		event->dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
916 		event->queue = SNDRV_SEQ_QUEUE_DIRECT;
917 	} else
918 #ifdef SUPPORT_BROADCAST
919 		if (event->queue == SNDRV_SEQ_ADDRESS_BROADCAST) {
920 			event->dest.client = SNDRV_SEQ_ADDRESS_BROADCAST;
921 			event->queue = SNDRV_SEQ_QUEUE_DIRECT;
922 		}
923 #endif
924 	if (event->dest.client == SNDRV_SEQ_ADDRESS_SUBSCRIBERS) {
925 		/* check presence of source port */
926 		struct snd_seq_client_port *src_port = snd_seq_port_use_ptr(client, event->source.port);
927 		if (src_port == NULL)
928 			return -EINVAL;
929 		snd_seq_port_unlock(src_port);
930 	}
931 
932 	/* direct event processing without enqueued */
933 	if (snd_seq_ev_is_direct(event)) {
934 		if (event->type == SNDRV_SEQ_EVENT_NOTE)
935 			return -EINVAL; /* this event must be enqueued! */
936 		return snd_seq_deliver_event(client, event, atomic, hop);
937 	}
938 
939 	/* Not direct, normal queuing */
940 	if (snd_seq_queue_is_used(event->queue, client->number) <= 0)
941 		return -EINVAL;  /* invalid queue */
942 	if (! snd_seq_write_pool_allocated(client))
943 		return -ENXIO; /* queue is not allocated */
944 
945 	/* allocate an event cell */
946 	err = snd_seq_event_dup(client->pool, event, &cell, !blocking || atomic, file);
947 	if (err < 0)
948 		return err;
949 
950 	/* we got a cell. enqueue it. */
951 	if ((err = snd_seq_enqueue_event(cell, atomic, hop)) < 0) {
952 		snd_seq_cell_free(cell);
953 		return err;
954 	}
955 
956 	return 0;
957 }
958 
959 
960 /*
961  * check validity of event type and data length.
962  * return non-zero if invalid.
963  */
964 static int check_event_type_and_length(struct snd_seq_event *ev)
965 {
966 	switch (snd_seq_ev_length_type(ev)) {
967 	case SNDRV_SEQ_EVENT_LENGTH_FIXED:
968 		if (snd_seq_ev_is_variable_type(ev))
969 			return -EINVAL;
970 		break;
971 	case SNDRV_SEQ_EVENT_LENGTH_VARIABLE:
972 		if (! snd_seq_ev_is_variable_type(ev) ||
973 		    (ev->data.ext.len & ~SNDRV_SEQ_EXT_MASK) >= SNDRV_SEQ_MAX_EVENT_LEN)
974 			return -EINVAL;
975 		break;
976 	case SNDRV_SEQ_EVENT_LENGTH_VARUSR:
977 		if (! snd_seq_ev_is_direct(ev))
978 			return -EINVAL;
979 		break;
980 	}
981 	return 0;
982 }
983 
984 
985 /* handle write() */
986 /* possible error values:
987  *	-ENXIO	invalid client or file open mode
988  *	-ENOMEM	malloc failed
989  *	-EFAULT	seg. fault during copy from user space
990  *	-EINVAL	invalid event
991  *	-EAGAIN	no space in output pool
992  *	-EINTR	interrupts while sleep
993  *	-EMLINK	too many hops
994  *	others	depends on return value from driver callback
995  */
996 static ssize_t snd_seq_write(struct file *file, const char __user *buf,
997 			     size_t count, loff_t *offset)
998 {
999 	struct snd_seq_client *client = file->private_data;
1000 	int written = 0, len;
1001 	int err = -EINVAL;
1002 	struct snd_seq_event event;
1003 
1004 	if (!(snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_OUTPUT))
1005 		return -ENXIO;
1006 
1007 	/* check client structures are in place */
1008 	if (snd_BUG_ON(!client))
1009 		return -ENXIO;
1010 
1011 	if (!client->accept_output || client->pool == NULL)
1012 		return -ENXIO;
1013 
1014 	/* allocate the pool now if the pool is not allocated yet */
1015 	if (client->pool->size > 0 && !snd_seq_write_pool_allocated(client)) {
1016 		if (snd_seq_pool_init(client->pool) < 0)
1017 			return -ENOMEM;
1018 	}
1019 
1020 	/* only process whole events */
1021 	while (count >= sizeof(struct snd_seq_event)) {
1022 		/* Read in the event header from the user */
1023 		len = sizeof(event);
1024 		if (copy_from_user(&event, buf, len)) {
1025 			err = -EFAULT;
1026 			break;
1027 		}
1028 		event.source.client = client->number;	/* fill in client number */
1029 		/* Check for extension data length */
1030 		if (check_event_type_and_length(&event)) {
1031 			err = -EINVAL;
1032 			break;
1033 		}
1034 
1035 		/* check for special events */
1036 		if (event.type == SNDRV_SEQ_EVENT_NONE)
1037 			goto __skip_event;
1038 		else if (snd_seq_ev_is_reserved(&event)) {
1039 			err = -EINVAL;
1040 			break;
1041 		}
1042 
1043 		if (snd_seq_ev_is_variable(&event)) {
1044 			int extlen = event.data.ext.len & ~SNDRV_SEQ_EXT_MASK;
1045 			if ((size_t)(extlen + len) > count) {
1046 				/* back out, will get an error this time or next */
1047 				err = -EINVAL;
1048 				break;
1049 			}
1050 			/* set user space pointer */
1051 			event.data.ext.len = extlen | SNDRV_SEQ_EXT_USRPTR;
1052 			event.data.ext.ptr = (char __force *)buf
1053 						+ sizeof(struct snd_seq_event);
1054 			len += extlen; /* increment data length */
1055 		} else {
1056 #ifdef CONFIG_COMPAT
1057 			if (client->convert32 && snd_seq_ev_is_varusr(&event)) {
1058 				void *ptr = (void __force *)compat_ptr(event.data.raw32.d[1]);
1059 				event.data.ext.ptr = ptr;
1060 			}
1061 #endif
1062 		}
1063 
1064 		/* ok, enqueue it */
1065 		err = snd_seq_client_enqueue_event(client, &event, file,
1066 						   !(file->f_flags & O_NONBLOCK),
1067 						   0, 0);
1068 		if (err < 0)
1069 			break;
1070 
1071 	__skip_event:
1072 		/* Update pointers and counts */
1073 		count -= len;
1074 		buf += len;
1075 		written += len;
1076 	}
1077 
1078 	return written ? written : err;
1079 }
1080 
1081 
1082 /*
1083  * handle polling
1084  */
1085 static unsigned int snd_seq_poll(struct file *file, poll_table * wait)
1086 {
1087 	struct snd_seq_client *client = file->private_data;
1088 	unsigned int mask = 0;
1089 
1090 	/* check client structures are in place */
1091 	if (snd_BUG_ON(!client))
1092 		return -ENXIO;
1093 
1094 	if ((snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_INPUT) &&
1095 	    client->data.user.fifo) {
1096 
1097 		/* check if data is available in the outqueue */
1098 		if (snd_seq_fifo_poll_wait(client->data.user.fifo, file, wait))
1099 			mask |= POLLIN | POLLRDNORM;
1100 	}
1101 
1102 	if (snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_OUTPUT) {
1103 
1104 		/* check if data is available in the pool */
1105 		if (!snd_seq_write_pool_allocated(client) ||
1106 		    snd_seq_pool_poll_wait(client->pool, file, wait))
1107 			mask |= POLLOUT | POLLWRNORM;
1108 	}
1109 
1110 	return mask;
1111 }
1112 
1113 
1114 /*-----------------------------------------------------*/
1115 
1116 static int snd_seq_ioctl_pversion(struct snd_seq_client *client, void *arg)
1117 {
1118 	int *pversion = arg;
1119 
1120 	*pversion = SNDRV_SEQ_VERSION;
1121 	return 0;
1122 }
1123 
1124 static int snd_seq_ioctl_client_id(struct snd_seq_client *client, void *arg)
1125 {
1126 	int *client_id = arg;
1127 
1128 	*client_id = client->number;
1129 	return 0;
1130 }
1131 
1132 /* SYSTEM_INFO ioctl() */
1133 static int snd_seq_ioctl_system_info(struct snd_seq_client *client, void *arg)
1134 {
1135 	struct snd_seq_system_info *info = arg;
1136 
1137 	memset(info, 0, sizeof(*info));
1138 	/* fill the info fields */
1139 	info->queues = SNDRV_SEQ_MAX_QUEUES;
1140 	info->clients = SNDRV_SEQ_MAX_CLIENTS;
1141 	info->ports = SNDRV_SEQ_MAX_PORTS;
1142 	info->channels = 256;	/* fixed limit */
1143 	info->cur_clients = client_usage.cur;
1144 	info->cur_queues = snd_seq_queue_get_cur_queues();
1145 
1146 	return 0;
1147 }
1148 
1149 
1150 /* RUNNING_MODE ioctl() */
1151 static int snd_seq_ioctl_running_mode(struct snd_seq_client *client, void  *arg)
1152 {
1153 	struct snd_seq_running_info *info = arg;
1154 	struct snd_seq_client *cptr;
1155 	int err = 0;
1156 
1157 	/* requested client number */
1158 	cptr = snd_seq_client_use_ptr(info->client);
1159 	if (cptr == NULL)
1160 		return -ENOENT;		/* don't change !!! */
1161 
1162 #ifdef SNDRV_BIG_ENDIAN
1163 	if (!info->big_endian) {
1164 		err = -EINVAL;
1165 		goto __err;
1166 	}
1167 #else
1168 	if (info->big_endian) {
1169 		err = -EINVAL;
1170 		goto __err;
1171 	}
1172 
1173 #endif
1174 	if (info->cpu_mode > sizeof(long)) {
1175 		err = -EINVAL;
1176 		goto __err;
1177 	}
1178 	cptr->convert32 = (info->cpu_mode < sizeof(long));
1179  __err:
1180 	snd_seq_client_unlock(cptr);
1181 	return err;
1182 }
1183 
1184 /* CLIENT_INFO ioctl() */
1185 static void get_client_info(struct snd_seq_client *cptr,
1186 			    struct snd_seq_client_info *info)
1187 {
1188 	info->client = cptr->number;
1189 
1190 	/* fill the info fields */
1191 	info->type = cptr->type;
1192 	strcpy(info->name, cptr->name);
1193 	info->filter = cptr->filter;
1194 	info->event_lost = cptr->event_lost;
1195 	memcpy(info->event_filter, cptr->event_filter, 32);
1196 	info->num_ports = cptr->num_ports;
1197 
1198 	if (cptr->type == USER_CLIENT)
1199 		info->pid = pid_vnr(cptr->data.user.owner);
1200 	else
1201 		info->pid = -1;
1202 
1203 	if (cptr->type == KERNEL_CLIENT)
1204 		info->card = cptr->data.kernel.card ? cptr->data.kernel.card->number : -1;
1205 	else
1206 		info->card = -1;
1207 
1208 	memset(info->reserved, 0, sizeof(info->reserved));
1209 }
1210 
1211 static int snd_seq_ioctl_get_client_info(struct snd_seq_client *client,
1212 					 void *arg)
1213 {
1214 	struct snd_seq_client_info *client_info = arg;
1215 	struct snd_seq_client *cptr;
1216 
1217 	/* requested client number */
1218 	cptr = snd_seq_client_use_ptr(client_info->client);
1219 	if (cptr == NULL)
1220 		return -ENOENT;		/* don't change !!! */
1221 
1222 	get_client_info(cptr, client_info);
1223 	snd_seq_client_unlock(cptr);
1224 
1225 	return 0;
1226 }
1227 
1228 
1229 /* CLIENT_INFO ioctl() */
1230 static int snd_seq_ioctl_set_client_info(struct snd_seq_client *client,
1231 					 void *arg)
1232 {
1233 	struct snd_seq_client_info *client_info = arg;
1234 
1235 	/* it is not allowed to set the info fields for an another client */
1236 	if (client->number != client_info->client)
1237 		return -EPERM;
1238 	/* also client type must be set now */
1239 	if (client->type != client_info->type)
1240 		return -EINVAL;
1241 
1242 	/* fill the info fields */
1243 	if (client_info->name[0])
1244 		strlcpy(client->name, client_info->name, sizeof(client->name));
1245 
1246 	client->filter = client_info->filter;
1247 	client->event_lost = client_info->event_lost;
1248 	memcpy(client->event_filter, client_info->event_filter, 32);
1249 
1250 	return 0;
1251 }
1252 
1253 
1254 /*
1255  * CREATE PORT ioctl()
1256  */
1257 static int snd_seq_ioctl_create_port(struct snd_seq_client *client, void *arg)
1258 {
1259 	struct snd_seq_port_info *info = arg;
1260 	struct snd_seq_client_port *port;
1261 	struct snd_seq_port_callback *callback;
1262 
1263 	/* it is not allowed to create the port for an another client */
1264 	if (info->addr.client != client->number)
1265 		return -EPERM;
1266 
1267 	port = snd_seq_create_port(client, (info->flags & SNDRV_SEQ_PORT_FLG_GIVEN_PORT) ? info->addr.port : -1);
1268 	if (port == NULL)
1269 		return -ENOMEM;
1270 
1271 	if (client->type == USER_CLIENT && info->kernel) {
1272 		snd_seq_delete_port(client, port->addr.port);
1273 		return -EINVAL;
1274 	}
1275 	if (client->type == KERNEL_CLIENT) {
1276 		if ((callback = info->kernel) != NULL) {
1277 			if (callback->owner)
1278 				port->owner = callback->owner;
1279 			port->private_data = callback->private_data;
1280 			port->private_free = callback->private_free;
1281 			port->event_input = callback->event_input;
1282 			port->c_src.open = callback->subscribe;
1283 			port->c_src.close = callback->unsubscribe;
1284 			port->c_dest.open = callback->use;
1285 			port->c_dest.close = callback->unuse;
1286 		}
1287 	}
1288 
1289 	info->addr = port->addr;
1290 
1291 	snd_seq_set_port_info(port, info);
1292 	snd_seq_system_client_ev_port_start(port->addr.client, port->addr.port);
1293 
1294 	return 0;
1295 }
1296 
1297 /*
1298  * DELETE PORT ioctl()
1299  */
1300 static int snd_seq_ioctl_delete_port(struct snd_seq_client *client, void *arg)
1301 {
1302 	struct snd_seq_port_info *info = arg;
1303 	int err;
1304 
1305 	/* it is not allowed to remove the port for an another client */
1306 	if (info->addr.client != client->number)
1307 		return -EPERM;
1308 
1309 	err = snd_seq_delete_port(client, info->addr.port);
1310 	if (err >= 0)
1311 		snd_seq_system_client_ev_port_exit(client->number, info->addr.port);
1312 	return err;
1313 }
1314 
1315 
1316 /*
1317  * GET_PORT_INFO ioctl() (on any client)
1318  */
1319 static int snd_seq_ioctl_get_port_info(struct snd_seq_client *client, void *arg)
1320 {
1321 	struct snd_seq_port_info *info = arg;
1322 	struct snd_seq_client *cptr;
1323 	struct snd_seq_client_port *port;
1324 
1325 	cptr = snd_seq_client_use_ptr(info->addr.client);
1326 	if (cptr == NULL)
1327 		return -ENXIO;
1328 
1329 	port = snd_seq_port_use_ptr(cptr, info->addr.port);
1330 	if (port == NULL) {
1331 		snd_seq_client_unlock(cptr);
1332 		return -ENOENT;			/* don't change */
1333 	}
1334 
1335 	/* get port info */
1336 	snd_seq_get_port_info(port, info);
1337 	snd_seq_port_unlock(port);
1338 	snd_seq_client_unlock(cptr);
1339 
1340 	return 0;
1341 }
1342 
1343 
1344 /*
1345  * SET_PORT_INFO ioctl() (only ports on this/own client)
1346  */
1347 static int snd_seq_ioctl_set_port_info(struct snd_seq_client *client, void *arg)
1348 {
1349 	struct snd_seq_port_info *info = arg;
1350 	struct snd_seq_client_port *port;
1351 
1352 	if (info->addr.client != client->number) /* only set our own ports ! */
1353 		return -EPERM;
1354 	port = snd_seq_port_use_ptr(client, info->addr.port);
1355 	if (port) {
1356 		snd_seq_set_port_info(port, info);
1357 		snd_seq_port_unlock(port);
1358 	}
1359 	return 0;
1360 }
1361 
1362 
1363 /*
1364  * port subscription (connection)
1365  */
1366 #define PERM_RD		(SNDRV_SEQ_PORT_CAP_READ|SNDRV_SEQ_PORT_CAP_SUBS_READ)
1367 #define PERM_WR		(SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_SUBS_WRITE)
1368 
1369 static int check_subscription_permission(struct snd_seq_client *client,
1370 					 struct snd_seq_client_port *sport,
1371 					 struct snd_seq_client_port *dport,
1372 					 struct snd_seq_port_subscribe *subs)
1373 {
1374 	if (client->number != subs->sender.client &&
1375 	    client->number != subs->dest.client) {
1376 		/* connection by third client - check export permission */
1377 		if (check_port_perm(sport, SNDRV_SEQ_PORT_CAP_NO_EXPORT))
1378 			return -EPERM;
1379 		if (check_port_perm(dport, SNDRV_SEQ_PORT_CAP_NO_EXPORT))
1380 			return -EPERM;
1381 	}
1382 
1383 	/* check read permission */
1384 	/* if sender or receiver is the subscribing client itself,
1385 	 * no permission check is necessary
1386 	 */
1387 	if (client->number != subs->sender.client) {
1388 		if (! check_port_perm(sport, PERM_RD))
1389 			return -EPERM;
1390 	}
1391 	/* check write permission */
1392 	if (client->number != subs->dest.client) {
1393 		if (! check_port_perm(dport, PERM_WR))
1394 			return -EPERM;
1395 	}
1396 	return 0;
1397 }
1398 
1399 /*
1400  * send an subscription notify event to user client:
1401  * client must be user client.
1402  */
1403 int snd_seq_client_notify_subscription(int client, int port,
1404 				       struct snd_seq_port_subscribe *info,
1405 				       int evtype)
1406 {
1407 	struct snd_seq_event event;
1408 
1409 	memset(&event, 0, sizeof(event));
1410 	event.type = evtype;
1411 	event.data.connect.dest = info->dest;
1412 	event.data.connect.sender = info->sender;
1413 
1414 	return snd_seq_system_notify(client, port, &event);  /* non-atomic */
1415 }
1416 
1417 
1418 /*
1419  * add to port's subscription list IOCTL interface
1420  */
1421 static int snd_seq_ioctl_subscribe_port(struct snd_seq_client *client,
1422 					void *arg)
1423 {
1424 	struct snd_seq_port_subscribe *subs = arg;
1425 	int result = -EINVAL;
1426 	struct snd_seq_client *receiver = NULL, *sender = NULL;
1427 	struct snd_seq_client_port *sport = NULL, *dport = NULL;
1428 
1429 	if ((receiver = snd_seq_client_use_ptr(subs->dest.client)) == NULL)
1430 		goto __end;
1431 	if ((sender = snd_seq_client_use_ptr(subs->sender.client)) == NULL)
1432 		goto __end;
1433 	if ((sport = snd_seq_port_use_ptr(sender, subs->sender.port)) == NULL)
1434 		goto __end;
1435 	if ((dport = snd_seq_port_use_ptr(receiver, subs->dest.port)) == NULL)
1436 		goto __end;
1437 
1438 	result = check_subscription_permission(client, sport, dport, subs);
1439 	if (result < 0)
1440 		goto __end;
1441 
1442 	/* connect them */
1443 	result = snd_seq_port_connect(client, sender, sport, receiver, dport, subs);
1444 	if (! result) /* broadcast announce */
1445 		snd_seq_client_notify_subscription(SNDRV_SEQ_ADDRESS_SUBSCRIBERS, 0,
1446 						   subs, SNDRV_SEQ_EVENT_PORT_SUBSCRIBED);
1447       __end:
1448       	if (sport)
1449 		snd_seq_port_unlock(sport);
1450 	if (dport)
1451 		snd_seq_port_unlock(dport);
1452 	if (sender)
1453 		snd_seq_client_unlock(sender);
1454 	if (receiver)
1455 		snd_seq_client_unlock(receiver);
1456 	return result;
1457 }
1458 
1459 
1460 /*
1461  * remove from port's subscription list
1462  */
1463 static int snd_seq_ioctl_unsubscribe_port(struct snd_seq_client *client,
1464 					  void *arg)
1465 {
1466 	struct snd_seq_port_subscribe *subs = arg;
1467 	int result = -ENXIO;
1468 	struct snd_seq_client *receiver = NULL, *sender = NULL;
1469 	struct snd_seq_client_port *sport = NULL, *dport = NULL;
1470 
1471 	if ((receiver = snd_seq_client_use_ptr(subs->dest.client)) == NULL)
1472 		goto __end;
1473 	if ((sender = snd_seq_client_use_ptr(subs->sender.client)) == NULL)
1474 		goto __end;
1475 	if ((sport = snd_seq_port_use_ptr(sender, subs->sender.port)) == NULL)
1476 		goto __end;
1477 	if ((dport = snd_seq_port_use_ptr(receiver, subs->dest.port)) == NULL)
1478 		goto __end;
1479 
1480 	result = check_subscription_permission(client, sport, dport, subs);
1481 	if (result < 0)
1482 		goto __end;
1483 
1484 	result = snd_seq_port_disconnect(client, sender, sport, receiver, dport, subs);
1485 	if (! result) /* broadcast announce */
1486 		snd_seq_client_notify_subscription(SNDRV_SEQ_ADDRESS_SUBSCRIBERS, 0,
1487 						   subs, SNDRV_SEQ_EVENT_PORT_UNSUBSCRIBED);
1488       __end:
1489       	if (sport)
1490 		snd_seq_port_unlock(sport);
1491 	if (dport)
1492 		snd_seq_port_unlock(dport);
1493 	if (sender)
1494 		snd_seq_client_unlock(sender);
1495 	if (receiver)
1496 		snd_seq_client_unlock(receiver);
1497 	return result;
1498 }
1499 
1500 
1501 /* CREATE_QUEUE ioctl() */
1502 static int snd_seq_ioctl_create_queue(struct snd_seq_client *client, void *arg)
1503 {
1504 	struct snd_seq_queue_info *info = arg;
1505 	int result;
1506 	struct snd_seq_queue *q;
1507 
1508 	result = snd_seq_queue_alloc(client->number, info->locked, info->flags);
1509 	if (result < 0)
1510 		return result;
1511 
1512 	q = queueptr(result);
1513 	if (q == NULL)
1514 		return -EINVAL;
1515 
1516 	info->queue = q->queue;
1517 	info->locked = q->locked;
1518 	info->owner = q->owner;
1519 
1520 	/* set queue name */
1521 	if (!info->name[0])
1522 		snprintf(info->name, sizeof(info->name), "Queue-%d", q->queue);
1523 	strlcpy(q->name, info->name, sizeof(q->name));
1524 	queuefree(q);
1525 
1526 	return 0;
1527 }
1528 
1529 /* DELETE_QUEUE ioctl() */
1530 static int snd_seq_ioctl_delete_queue(struct snd_seq_client *client, void *arg)
1531 {
1532 	struct snd_seq_queue_info *info = arg;
1533 
1534 	return snd_seq_queue_delete(client->number, info->queue);
1535 }
1536 
1537 /* GET_QUEUE_INFO ioctl() */
1538 static int snd_seq_ioctl_get_queue_info(struct snd_seq_client *client,
1539 					void *arg)
1540 {
1541 	struct snd_seq_queue_info *info = arg;
1542 	struct snd_seq_queue *q;
1543 
1544 	q = queueptr(info->queue);
1545 	if (q == NULL)
1546 		return -EINVAL;
1547 
1548 	memset(info, 0, sizeof(*info));
1549 	info->queue = q->queue;
1550 	info->owner = q->owner;
1551 	info->locked = q->locked;
1552 	strlcpy(info->name, q->name, sizeof(info->name));
1553 	queuefree(q);
1554 
1555 	return 0;
1556 }
1557 
1558 /* SET_QUEUE_INFO ioctl() */
1559 static int snd_seq_ioctl_set_queue_info(struct snd_seq_client *client,
1560 					void *arg)
1561 {
1562 	struct snd_seq_queue_info *info = arg;
1563 	struct snd_seq_queue *q;
1564 
1565 	if (info->owner != client->number)
1566 		return -EINVAL;
1567 
1568 	/* change owner/locked permission */
1569 	if (snd_seq_queue_check_access(info->queue, client->number)) {
1570 		if (snd_seq_queue_set_owner(info->queue, client->number, info->locked) < 0)
1571 			return -EPERM;
1572 		if (info->locked)
1573 			snd_seq_queue_use(info->queue, client->number, 1);
1574 	} else {
1575 		return -EPERM;
1576 	}
1577 
1578 	q = queueptr(info->queue);
1579 	if (! q)
1580 		return -EINVAL;
1581 	if (q->owner != client->number) {
1582 		queuefree(q);
1583 		return -EPERM;
1584 	}
1585 	strlcpy(q->name, info->name, sizeof(q->name));
1586 	queuefree(q);
1587 
1588 	return 0;
1589 }
1590 
1591 /* GET_NAMED_QUEUE ioctl() */
1592 static int snd_seq_ioctl_get_named_queue(struct snd_seq_client *client,
1593 					 void *arg)
1594 {
1595 	struct snd_seq_queue_info *info = arg;
1596 	struct snd_seq_queue *q;
1597 
1598 	q = snd_seq_queue_find_name(info->name);
1599 	if (q == NULL)
1600 		return -EINVAL;
1601 	info->queue = q->queue;
1602 	info->owner = q->owner;
1603 	info->locked = q->locked;
1604 	queuefree(q);
1605 
1606 	return 0;
1607 }
1608 
1609 /* GET_QUEUE_STATUS ioctl() */
1610 static int snd_seq_ioctl_get_queue_status(struct snd_seq_client *client,
1611 					  void *arg)
1612 {
1613 	struct snd_seq_queue_status *status = arg;
1614 	struct snd_seq_queue *queue;
1615 	struct snd_seq_timer *tmr;
1616 
1617 	queue = queueptr(status->queue);
1618 	if (queue == NULL)
1619 		return -EINVAL;
1620 	memset(status, 0, sizeof(*status));
1621 	status->queue = queue->queue;
1622 
1623 	tmr = queue->timer;
1624 	status->events = queue->tickq->cells + queue->timeq->cells;
1625 
1626 	status->time = snd_seq_timer_get_cur_time(tmr);
1627 	status->tick = snd_seq_timer_get_cur_tick(tmr);
1628 
1629 	status->running = tmr->running;
1630 
1631 	status->flags = queue->flags;
1632 	queuefree(queue);
1633 
1634 	return 0;
1635 }
1636 
1637 
1638 /* GET_QUEUE_TEMPO ioctl() */
1639 static int snd_seq_ioctl_get_queue_tempo(struct snd_seq_client *client,
1640 					 void *arg)
1641 {
1642 	struct snd_seq_queue_tempo *tempo = arg;
1643 	struct snd_seq_queue *queue;
1644 	struct snd_seq_timer *tmr;
1645 
1646 	queue = queueptr(tempo->queue);
1647 	if (queue == NULL)
1648 		return -EINVAL;
1649 	memset(tempo, 0, sizeof(*tempo));
1650 	tempo->queue = queue->queue;
1651 
1652 	tmr = queue->timer;
1653 
1654 	tempo->tempo = tmr->tempo;
1655 	tempo->ppq = tmr->ppq;
1656 	tempo->skew_value = tmr->skew;
1657 	tempo->skew_base = tmr->skew_base;
1658 	queuefree(queue);
1659 
1660 	return 0;
1661 }
1662 
1663 
1664 /* SET_QUEUE_TEMPO ioctl() */
1665 int snd_seq_set_queue_tempo(int client, struct snd_seq_queue_tempo *tempo)
1666 {
1667 	if (!snd_seq_queue_check_access(tempo->queue, client))
1668 		return -EPERM;
1669 	return snd_seq_queue_timer_set_tempo(tempo->queue, client, tempo);
1670 }
1671 
1672 EXPORT_SYMBOL(snd_seq_set_queue_tempo);
1673 
1674 static int snd_seq_ioctl_set_queue_tempo(struct snd_seq_client *client,
1675 					 void *arg)
1676 {
1677 	struct snd_seq_queue_tempo *tempo = arg;
1678 	int result;
1679 
1680 	result = snd_seq_set_queue_tempo(client->number, tempo);
1681 	return result < 0 ? result : 0;
1682 }
1683 
1684 
1685 /* GET_QUEUE_TIMER ioctl() */
1686 static int snd_seq_ioctl_get_queue_timer(struct snd_seq_client *client,
1687 					 void *arg)
1688 {
1689 	struct snd_seq_queue_timer *timer = arg;
1690 	struct snd_seq_queue *queue;
1691 	struct snd_seq_timer *tmr;
1692 
1693 	queue = queueptr(timer->queue);
1694 	if (queue == NULL)
1695 		return -EINVAL;
1696 
1697 	if (mutex_lock_interruptible(&queue->timer_mutex)) {
1698 		queuefree(queue);
1699 		return -ERESTARTSYS;
1700 	}
1701 	tmr = queue->timer;
1702 	memset(timer, 0, sizeof(*timer));
1703 	timer->queue = queue->queue;
1704 
1705 	timer->type = tmr->type;
1706 	if (tmr->type == SNDRV_SEQ_TIMER_ALSA) {
1707 		timer->u.alsa.id = tmr->alsa_id;
1708 		timer->u.alsa.resolution = tmr->preferred_resolution;
1709 	}
1710 	mutex_unlock(&queue->timer_mutex);
1711 	queuefree(queue);
1712 
1713 	return 0;
1714 }
1715 
1716 
1717 /* SET_QUEUE_TIMER ioctl() */
1718 static int snd_seq_ioctl_set_queue_timer(struct snd_seq_client *client,
1719 					 void *arg)
1720 {
1721 	struct snd_seq_queue_timer *timer = arg;
1722 	int result = 0;
1723 
1724 	if (timer->type != SNDRV_SEQ_TIMER_ALSA)
1725 		return -EINVAL;
1726 
1727 	if (snd_seq_queue_check_access(timer->queue, client->number)) {
1728 		struct snd_seq_queue *q;
1729 		struct snd_seq_timer *tmr;
1730 
1731 		q = queueptr(timer->queue);
1732 		if (q == NULL)
1733 			return -ENXIO;
1734 		if (mutex_lock_interruptible(&q->timer_mutex)) {
1735 			queuefree(q);
1736 			return -ERESTARTSYS;
1737 		}
1738 		tmr = q->timer;
1739 		snd_seq_queue_timer_close(timer->queue);
1740 		tmr->type = timer->type;
1741 		if (tmr->type == SNDRV_SEQ_TIMER_ALSA) {
1742 			tmr->alsa_id = timer->u.alsa.id;
1743 			tmr->preferred_resolution = timer->u.alsa.resolution;
1744 		}
1745 		result = snd_seq_queue_timer_open(timer->queue);
1746 		mutex_unlock(&q->timer_mutex);
1747 		queuefree(q);
1748 	} else {
1749 		return -EPERM;
1750 	}
1751 
1752 	return result;
1753 }
1754 
1755 
1756 /* GET_QUEUE_CLIENT ioctl() */
1757 static int snd_seq_ioctl_get_queue_client(struct snd_seq_client *client,
1758 					  void *arg)
1759 {
1760 	struct snd_seq_queue_client *info = arg;
1761 	int used;
1762 
1763 	used = snd_seq_queue_is_used(info->queue, client->number);
1764 	if (used < 0)
1765 		return -EINVAL;
1766 	info->used = used;
1767 	info->client = client->number;
1768 
1769 	return 0;
1770 }
1771 
1772 
1773 /* SET_QUEUE_CLIENT ioctl() */
1774 static int snd_seq_ioctl_set_queue_client(struct snd_seq_client *client,
1775 					  void *arg)
1776 {
1777 	struct snd_seq_queue_client *info = arg;
1778 	int err;
1779 
1780 	if (info->used >= 0) {
1781 		err = snd_seq_queue_use(info->queue, client->number, info->used);
1782 		if (err < 0)
1783 			return err;
1784 	}
1785 
1786 	return snd_seq_ioctl_get_queue_client(client, arg);
1787 }
1788 
1789 
1790 /* GET_CLIENT_POOL ioctl() */
1791 static int snd_seq_ioctl_get_client_pool(struct snd_seq_client *client,
1792 					 void *arg)
1793 {
1794 	struct snd_seq_client_pool *info = arg;
1795 	struct snd_seq_client *cptr;
1796 
1797 	cptr = snd_seq_client_use_ptr(info->client);
1798 	if (cptr == NULL)
1799 		return -ENOENT;
1800 	memset(info, 0, sizeof(*info));
1801 	info->client = cptr->number;
1802 	info->output_pool = cptr->pool->size;
1803 	info->output_room = cptr->pool->room;
1804 	info->output_free = info->output_pool;
1805 	info->output_free = snd_seq_unused_cells(cptr->pool);
1806 	if (cptr->type == USER_CLIENT) {
1807 		info->input_pool = cptr->data.user.fifo_pool_size;
1808 		info->input_free = info->input_pool;
1809 		if (cptr->data.user.fifo)
1810 			info->input_free = snd_seq_unused_cells(cptr->data.user.fifo->pool);
1811 	} else {
1812 		info->input_pool = 0;
1813 		info->input_free = 0;
1814 	}
1815 	snd_seq_client_unlock(cptr);
1816 
1817 	return 0;
1818 }
1819 
1820 /* SET_CLIENT_POOL ioctl() */
1821 static int snd_seq_ioctl_set_client_pool(struct snd_seq_client *client,
1822 					 void *arg)
1823 {
1824 	struct snd_seq_client_pool *info = arg;
1825 	int rc;
1826 
1827 	if (client->number != info->client)
1828 		return -EINVAL; /* can't change other clients */
1829 
1830 	if (info->output_pool >= 1 && info->output_pool <= SNDRV_SEQ_MAX_EVENTS &&
1831 	    (! snd_seq_write_pool_allocated(client) ||
1832 	     info->output_pool != client->pool->size)) {
1833 		if (snd_seq_write_pool_allocated(client)) {
1834 			/* remove all existing cells */
1835 			snd_seq_queue_client_leave_cells(client->number);
1836 			snd_seq_pool_done(client->pool);
1837 		}
1838 		client->pool->size = info->output_pool;
1839 		rc = snd_seq_pool_init(client->pool);
1840 		if (rc < 0)
1841 			return rc;
1842 	}
1843 	if (client->type == USER_CLIENT && client->data.user.fifo != NULL &&
1844 	    info->input_pool >= 1 &&
1845 	    info->input_pool <= SNDRV_SEQ_MAX_CLIENT_EVENTS &&
1846 	    info->input_pool != client->data.user.fifo_pool_size) {
1847 		/* change pool size */
1848 		rc = snd_seq_fifo_resize(client->data.user.fifo, info->input_pool);
1849 		if (rc < 0)
1850 			return rc;
1851 		client->data.user.fifo_pool_size = info->input_pool;
1852 	}
1853 	if (info->output_room >= 1 &&
1854 	    info->output_room <= client->pool->size) {
1855 		client->pool->room  = info->output_room;
1856 	}
1857 
1858 	return snd_seq_ioctl_get_client_pool(client, arg);
1859 }
1860 
1861 
1862 /* REMOVE_EVENTS ioctl() */
1863 static int snd_seq_ioctl_remove_events(struct snd_seq_client *client,
1864 				       void *arg)
1865 {
1866 	struct snd_seq_remove_events *info = arg;
1867 
1868 	/*
1869 	 * Input mostly not implemented XXX.
1870 	 */
1871 	if (info->remove_mode & SNDRV_SEQ_REMOVE_INPUT) {
1872 		/*
1873 		 * No restrictions so for a user client we can clear
1874 		 * the whole fifo
1875 		 */
1876 		if (client->type == USER_CLIENT && client->data.user.fifo)
1877 			snd_seq_fifo_clear(client->data.user.fifo);
1878 	}
1879 
1880 	if (info->remove_mode & SNDRV_SEQ_REMOVE_OUTPUT)
1881 		snd_seq_queue_remove_cells(client->number, info);
1882 
1883 	return 0;
1884 }
1885 
1886 
1887 /*
1888  * get subscription info
1889  */
1890 static int snd_seq_ioctl_get_subscription(struct snd_seq_client *client,
1891 					  void *arg)
1892 {
1893 	struct snd_seq_port_subscribe *subs = arg;
1894 	int result;
1895 	struct snd_seq_client *sender = NULL;
1896 	struct snd_seq_client_port *sport = NULL;
1897 	struct snd_seq_subscribers *p;
1898 
1899 	result = -EINVAL;
1900 	if ((sender = snd_seq_client_use_ptr(subs->sender.client)) == NULL)
1901 		goto __end;
1902 	if ((sport = snd_seq_port_use_ptr(sender, subs->sender.port)) == NULL)
1903 		goto __end;
1904 	p = snd_seq_port_get_subscription(&sport->c_src, &subs->dest);
1905 	if (p) {
1906 		result = 0;
1907 		*subs = p->info;
1908 	} else
1909 		result = -ENOENT;
1910 
1911       __end:
1912       	if (sport)
1913 		snd_seq_port_unlock(sport);
1914 	if (sender)
1915 		snd_seq_client_unlock(sender);
1916 
1917 	return result;
1918 }
1919 
1920 
1921 /*
1922  * get subscription info - check only its presence
1923  */
1924 static int snd_seq_ioctl_query_subs(struct snd_seq_client *client, void *arg)
1925 {
1926 	struct snd_seq_query_subs *subs = arg;
1927 	int result = -ENXIO;
1928 	struct snd_seq_client *cptr = NULL;
1929 	struct snd_seq_client_port *port = NULL;
1930 	struct snd_seq_port_subs_info *group;
1931 	struct list_head *p;
1932 	int i;
1933 
1934 	if ((cptr = snd_seq_client_use_ptr(subs->root.client)) == NULL)
1935 		goto __end;
1936 	if ((port = snd_seq_port_use_ptr(cptr, subs->root.port)) == NULL)
1937 		goto __end;
1938 
1939 	switch (subs->type) {
1940 	case SNDRV_SEQ_QUERY_SUBS_READ:
1941 		group = &port->c_src;
1942 		break;
1943 	case SNDRV_SEQ_QUERY_SUBS_WRITE:
1944 		group = &port->c_dest;
1945 		break;
1946 	default:
1947 		goto __end;
1948 	}
1949 
1950 	down_read(&group->list_mutex);
1951 	/* search for the subscriber */
1952 	subs->num_subs = group->count;
1953 	i = 0;
1954 	result = -ENOENT;
1955 	list_for_each(p, &group->list_head) {
1956 		if (i++ == subs->index) {
1957 			/* found! */
1958 			struct snd_seq_subscribers *s;
1959 			if (subs->type == SNDRV_SEQ_QUERY_SUBS_READ) {
1960 				s = list_entry(p, struct snd_seq_subscribers, src_list);
1961 				subs->addr = s->info.dest;
1962 			} else {
1963 				s = list_entry(p, struct snd_seq_subscribers, dest_list);
1964 				subs->addr = s->info.sender;
1965 			}
1966 			subs->flags = s->info.flags;
1967 			subs->queue = s->info.queue;
1968 			result = 0;
1969 			break;
1970 		}
1971 	}
1972 	up_read(&group->list_mutex);
1973 
1974       __end:
1975    	if (port)
1976 		snd_seq_port_unlock(port);
1977 	if (cptr)
1978 		snd_seq_client_unlock(cptr);
1979 
1980 	return result;
1981 }
1982 
1983 
1984 /*
1985  * query next client
1986  */
1987 static int snd_seq_ioctl_query_next_client(struct snd_seq_client *client,
1988 					   void *arg)
1989 {
1990 	struct snd_seq_client_info *info = arg;
1991 	struct snd_seq_client *cptr = NULL;
1992 
1993 	/* search for next client */
1994 	info->client++;
1995 	if (info->client < 0)
1996 		info->client = 0;
1997 	for (; info->client < SNDRV_SEQ_MAX_CLIENTS; info->client++) {
1998 		cptr = snd_seq_client_use_ptr(info->client);
1999 		if (cptr)
2000 			break; /* found */
2001 	}
2002 	if (cptr == NULL)
2003 		return -ENOENT;
2004 
2005 	get_client_info(cptr, info);
2006 	snd_seq_client_unlock(cptr);
2007 
2008 	return 0;
2009 }
2010 
2011 /*
2012  * query next port
2013  */
2014 static int snd_seq_ioctl_query_next_port(struct snd_seq_client *client,
2015 					 void *arg)
2016 {
2017 	struct snd_seq_port_info *info = arg;
2018 	struct snd_seq_client *cptr;
2019 	struct snd_seq_client_port *port = NULL;
2020 
2021 	cptr = snd_seq_client_use_ptr(info->addr.client);
2022 	if (cptr == NULL)
2023 		return -ENXIO;
2024 
2025 	/* search for next port */
2026 	info->addr.port++;
2027 	port = snd_seq_port_query_nearest(cptr, info);
2028 	if (port == NULL) {
2029 		snd_seq_client_unlock(cptr);
2030 		return -ENOENT;
2031 	}
2032 
2033 	/* get port info */
2034 	info->addr = port->addr;
2035 	snd_seq_get_port_info(port, info);
2036 	snd_seq_port_unlock(port);
2037 	snd_seq_client_unlock(cptr);
2038 
2039 	return 0;
2040 }
2041 
2042 /* -------------------------------------------------------- */
2043 
2044 static const struct ioctl_handler {
2045 	unsigned int cmd;
2046 	int (*func)(struct snd_seq_client *client, void *arg);
2047 } ioctl_handlers[] = {
2048 	{ SNDRV_SEQ_IOCTL_PVERSION, snd_seq_ioctl_pversion },
2049 	{ SNDRV_SEQ_IOCTL_CLIENT_ID, snd_seq_ioctl_client_id },
2050 	{ SNDRV_SEQ_IOCTL_SYSTEM_INFO, snd_seq_ioctl_system_info },
2051 	{ SNDRV_SEQ_IOCTL_RUNNING_MODE, snd_seq_ioctl_running_mode },
2052 	{ SNDRV_SEQ_IOCTL_GET_CLIENT_INFO, snd_seq_ioctl_get_client_info },
2053 	{ SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, snd_seq_ioctl_set_client_info },
2054 	{ SNDRV_SEQ_IOCTL_CREATE_PORT, snd_seq_ioctl_create_port },
2055 	{ SNDRV_SEQ_IOCTL_DELETE_PORT, snd_seq_ioctl_delete_port },
2056 	{ SNDRV_SEQ_IOCTL_GET_PORT_INFO, snd_seq_ioctl_get_port_info },
2057 	{ SNDRV_SEQ_IOCTL_SET_PORT_INFO, snd_seq_ioctl_set_port_info },
2058 	{ SNDRV_SEQ_IOCTL_SUBSCRIBE_PORT, snd_seq_ioctl_subscribe_port },
2059 	{ SNDRV_SEQ_IOCTL_UNSUBSCRIBE_PORT, snd_seq_ioctl_unsubscribe_port },
2060 	{ SNDRV_SEQ_IOCTL_CREATE_QUEUE, snd_seq_ioctl_create_queue },
2061 	{ SNDRV_SEQ_IOCTL_DELETE_QUEUE, snd_seq_ioctl_delete_queue },
2062 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_INFO, snd_seq_ioctl_get_queue_info },
2063 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_INFO, snd_seq_ioctl_set_queue_info },
2064 	{ SNDRV_SEQ_IOCTL_GET_NAMED_QUEUE, snd_seq_ioctl_get_named_queue },
2065 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_STATUS, snd_seq_ioctl_get_queue_status },
2066 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_TEMPO, snd_seq_ioctl_get_queue_tempo },
2067 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_TEMPO, snd_seq_ioctl_set_queue_tempo },
2068 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_TIMER, snd_seq_ioctl_get_queue_timer },
2069 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_TIMER, snd_seq_ioctl_set_queue_timer },
2070 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_CLIENT, snd_seq_ioctl_get_queue_client },
2071 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_CLIENT, snd_seq_ioctl_set_queue_client },
2072 	{ SNDRV_SEQ_IOCTL_GET_CLIENT_POOL, snd_seq_ioctl_get_client_pool },
2073 	{ SNDRV_SEQ_IOCTL_SET_CLIENT_POOL, snd_seq_ioctl_set_client_pool },
2074 	{ SNDRV_SEQ_IOCTL_GET_SUBSCRIPTION, snd_seq_ioctl_get_subscription },
2075 	{ SNDRV_SEQ_IOCTL_QUERY_NEXT_CLIENT, snd_seq_ioctl_query_next_client },
2076 	{ SNDRV_SEQ_IOCTL_QUERY_NEXT_PORT, snd_seq_ioctl_query_next_port },
2077 	{ SNDRV_SEQ_IOCTL_REMOVE_EVENTS, snd_seq_ioctl_remove_events },
2078 	{ SNDRV_SEQ_IOCTL_QUERY_SUBS, snd_seq_ioctl_query_subs },
2079 	{ 0, NULL },
2080 };
2081 
2082 static long snd_seq_ioctl(struct file *file, unsigned int cmd,
2083 			  unsigned long arg)
2084 {
2085 	struct snd_seq_client *client = file->private_data;
2086 	/* To use kernel stack for ioctl data. */
2087 	union {
2088 		int pversion;
2089 		int client_id;
2090 		struct snd_seq_system_info	system_info;
2091 		struct snd_seq_running_info	running_info;
2092 		struct snd_seq_client_info	client_info;
2093 		struct snd_seq_port_info	port_info;
2094 		struct snd_seq_port_subscribe	port_subscribe;
2095 		struct snd_seq_queue_info	queue_info;
2096 		struct snd_seq_queue_status	queue_status;
2097 		struct snd_seq_queue_tempo	tempo;
2098 		struct snd_seq_queue_timer	queue_timer;
2099 		struct snd_seq_queue_client	queue_client;
2100 		struct snd_seq_client_pool	client_pool;
2101 		struct snd_seq_remove_events	remove_events;
2102 		struct snd_seq_query_subs	query_subs;
2103 	} buf;
2104 	const struct ioctl_handler *handler;
2105 	unsigned long size;
2106 	int err;
2107 
2108 	if (snd_BUG_ON(!client))
2109 		return -ENXIO;
2110 
2111 	for (handler = ioctl_handlers; handler->cmd > 0; ++handler) {
2112 		if (handler->cmd == cmd)
2113 			break;
2114 	}
2115 	if (handler->cmd == 0)
2116 		return -ENOTTY;
2117 
2118 	memset(&buf, 0, sizeof(buf));
2119 
2120 	/*
2121 	 * All of ioctl commands for ALSA sequencer get an argument of size
2122 	 * within 13 bits. We can safely pick up the size from the command.
2123 	 */
2124 	size = _IOC_SIZE(handler->cmd);
2125 	if (handler->cmd & IOC_IN) {
2126 		if (copy_from_user(&buf, (const void __user *)arg, size))
2127 			return -EFAULT;
2128 	}
2129 
2130 	err = handler->func(client, &buf);
2131 	if (err >= 0) {
2132 		/* Some commands includes a bug in 'dir' field. */
2133 		if (handler->cmd == SNDRV_SEQ_IOCTL_SET_QUEUE_CLIENT ||
2134 		    handler->cmd == SNDRV_SEQ_IOCTL_SET_CLIENT_POOL ||
2135 		    (handler->cmd & IOC_OUT))
2136 			if (copy_to_user((void __user *)arg, &buf, size))
2137 				return -EFAULT;
2138 	}
2139 
2140 	return err;
2141 }
2142 
2143 #ifdef CONFIG_COMPAT
2144 #include "seq_compat.c"
2145 #else
2146 #define snd_seq_ioctl_compat	NULL
2147 #endif
2148 
2149 /* -------------------------------------------------------- */
2150 
2151 
2152 /* exported to kernel modules */
2153 int snd_seq_create_kernel_client(struct snd_card *card, int client_index,
2154 				 const char *name_fmt, ...)
2155 {
2156 	struct snd_seq_client *client;
2157 	va_list args;
2158 
2159 	if (snd_BUG_ON(in_interrupt()))
2160 		return -EBUSY;
2161 
2162 	if (card && client_index >= SNDRV_SEQ_CLIENTS_PER_CARD)
2163 		return -EINVAL;
2164 	if (card == NULL && client_index >= SNDRV_SEQ_GLOBAL_CLIENTS)
2165 		return -EINVAL;
2166 
2167 	if (mutex_lock_interruptible(&register_mutex))
2168 		return -ERESTARTSYS;
2169 
2170 	if (card) {
2171 		client_index += SNDRV_SEQ_GLOBAL_CLIENTS
2172 			+ card->number * SNDRV_SEQ_CLIENTS_PER_CARD;
2173 		if (client_index >= SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN)
2174 			client_index = -1;
2175 	}
2176 
2177 	/* empty write queue as default */
2178 	client = seq_create_client1(client_index, 0);
2179 	if (client == NULL) {
2180 		mutex_unlock(&register_mutex);
2181 		return -EBUSY;	/* failure code */
2182 	}
2183 	usage_alloc(&client_usage, 1);
2184 
2185 	client->accept_input = 1;
2186 	client->accept_output = 1;
2187 	client->data.kernel.card = card;
2188 
2189 	va_start(args, name_fmt);
2190 	vsnprintf(client->name, sizeof(client->name), name_fmt, args);
2191 	va_end(args);
2192 
2193 	client->type = KERNEL_CLIENT;
2194 	mutex_unlock(&register_mutex);
2195 
2196 	/* make others aware this new client */
2197 	snd_seq_system_client_ev_client_start(client->number);
2198 
2199 	/* return client number to caller */
2200 	return client->number;
2201 }
2202 
2203 EXPORT_SYMBOL(snd_seq_create_kernel_client);
2204 
2205 /* exported to kernel modules */
2206 int snd_seq_delete_kernel_client(int client)
2207 {
2208 	struct snd_seq_client *ptr;
2209 
2210 	if (snd_BUG_ON(in_interrupt()))
2211 		return -EBUSY;
2212 
2213 	ptr = clientptr(client);
2214 	if (ptr == NULL)
2215 		return -EINVAL;
2216 
2217 	seq_free_client(ptr);
2218 	kfree(ptr);
2219 	return 0;
2220 }
2221 
2222 EXPORT_SYMBOL(snd_seq_delete_kernel_client);
2223 
2224 /* skeleton to enqueue event, called from snd_seq_kernel_client_enqueue
2225  * and snd_seq_kernel_client_enqueue_blocking
2226  */
2227 static int kernel_client_enqueue(int client, struct snd_seq_event *ev,
2228 				 struct file *file, int blocking,
2229 				 int atomic, int hop)
2230 {
2231 	struct snd_seq_client *cptr;
2232 	int result;
2233 
2234 	if (snd_BUG_ON(!ev))
2235 		return -EINVAL;
2236 
2237 	if (ev->type == SNDRV_SEQ_EVENT_NONE)
2238 		return 0; /* ignore this */
2239 	if (ev->type == SNDRV_SEQ_EVENT_KERNEL_ERROR)
2240 		return -EINVAL; /* quoted events can't be enqueued */
2241 
2242 	/* fill in client number */
2243 	ev->source.client = client;
2244 
2245 	if (check_event_type_and_length(ev))
2246 		return -EINVAL;
2247 
2248 	cptr = snd_seq_client_use_ptr(client);
2249 	if (cptr == NULL)
2250 		return -EINVAL;
2251 
2252 	if (! cptr->accept_output)
2253 		result = -EPERM;
2254 	else /* send it */
2255 		result = snd_seq_client_enqueue_event(cptr, ev, file, blocking, atomic, hop);
2256 
2257 	snd_seq_client_unlock(cptr);
2258 	return result;
2259 }
2260 
2261 /*
2262  * exported, called by kernel clients to enqueue events (w/o blocking)
2263  *
2264  * RETURN VALUE: zero if succeed, negative if error
2265  */
2266 int snd_seq_kernel_client_enqueue(int client, struct snd_seq_event * ev,
2267 				  int atomic, int hop)
2268 {
2269 	return kernel_client_enqueue(client, ev, NULL, 0, atomic, hop);
2270 }
2271 
2272 EXPORT_SYMBOL(snd_seq_kernel_client_enqueue);
2273 
2274 /*
2275  * exported, called by kernel clients to enqueue events (with blocking)
2276  *
2277  * RETURN VALUE: zero if succeed, negative if error
2278  */
2279 int snd_seq_kernel_client_enqueue_blocking(int client, struct snd_seq_event * ev,
2280 					   struct file *file,
2281 					   int atomic, int hop)
2282 {
2283 	return kernel_client_enqueue(client, ev, file, 1, atomic, hop);
2284 }
2285 
2286 EXPORT_SYMBOL(snd_seq_kernel_client_enqueue_blocking);
2287 
2288 /*
2289  * exported, called by kernel clients to dispatch events directly to other
2290  * clients, bypassing the queues.  Event time-stamp will be updated.
2291  *
2292  * RETURN VALUE: negative = delivery failed,
2293  *		 zero, or positive: the number of delivered events
2294  */
2295 int snd_seq_kernel_client_dispatch(int client, struct snd_seq_event * ev,
2296 				   int atomic, int hop)
2297 {
2298 	struct snd_seq_client *cptr;
2299 	int result;
2300 
2301 	if (snd_BUG_ON(!ev))
2302 		return -EINVAL;
2303 
2304 	/* fill in client number */
2305 	ev->queue = SNDRV_SEQ_QUEUE_DIRECT;
2306 	ev->source.client = client;
2307 
2308 	if (check_event_type_and_length(ev))
2309 		return -EINVAL;
2310 
2311 	cptr = snd_seq_client_use_ptr(client);
2312 	if (cptr == NULL)
2313 		return -EINVAL;
2314 
2315 	if (!cptr->accept_output)
2316 		result = -EPERM;
2317 	else
2318 		result = snd_seq_deliver_event(cptr, ev, atomic, hop);
2319 
2320 	snd_seq_client_unlock(cptr);
2321 	return result;
2322 }
2323 
2324 EXPORT_SYMBOL(snd_seq_kernel_client_dispatch);
2325 
2326 /**
2327  * snd_seq_kernel_client_ctl - operate a command for a client with data in
2328  *			       kernel space.
2329  * @clientid:	A numerical ID for a client.
2330  * @cmd:	An ioctl(2) command for ALSA sequencer operation.
2331  * @arg:	A pointer to data in kernel space.
2332  *
2333  * Against its name, both kernel/application client can be handled by this
2334  * kernel API. A pointer of 'arg' argument should be in kernel space.
2335  *
2336  * Return: 0 at success. Negative error code at failure.
2337  */
2338 int snd_seq_kernel_client_ctl(int clientid, unsigned int cmd, void *arg)
2339 {
2340 	const struct ioctl_handler *handler;
2341 	struct snd_seq_client *client;
2342 
2343 	client = clientptr(clientid);
2344 	if (client == NULL)
2345 		return -ENXIO;
2346 
2347 	for (handler = ioctl_handlers; handler->cmd > 0; ++handler) {
2348 		if (handler->cmd == cmd)
2349 			return handler->func(client, arg);
2350 	}
2351 
2352 	pr_debug("ALSA: seq unknown ioctl() 0x%x (type='%c', number=0x%02x)\n",
2353 		 cmd, _IOC_TYPE(cmd), _IOC_NR(cmd));
2354 	return -ENOTTY;
2355 }
2356 
2357 EXPORT_SYMBOL(snd_seq_kernel_client_ctl);
2358 
2359 /* exported (for OSS emulator) */
2360 int snd_seq_kernel_client_write_poll(int clientid, struct file *file, poll_table *wait)
2361 {
2362 	struct snd_seq_client *client;
2363 
2364 	client = clientptr(clientid);
2365 	if (client == NULL)
2366 		return -ENXIO;
2367 
2368 	if (! snd_seq_write_pool_allocated(client))
2369 		return 1;
2370 	if (snd_seq_pool_poll_wait(client->pool, file, wait))
2371 		return 1;
2372 	return 0;
2373 }
2374 
2375 EXPORT_SYMBOL(snd_seq_kernel_client_write_poll);
2376 
2377 /*---------------------------------------------------------------------------*/
2378 
2379 #ifdef CONFIG_SND_PROC_FS
2380 /*
2381  *  /proc interface
2382  */
2383 static void snd_seq_info_dump_subscribers(struct snd_info_buffer *buffer,
2384 					  struct snd_seq_port_subs_info *group,
2385 					  int is_src, char *msg)
2386 {
2387 	struct list_head *p;
2388 	struct snd_seq_subscribers *s;
2389 	int count = 0;
2390 
2391 	down_read(&group->list_mutex);
2392 	if (list_empty(&group->list_head)) {
2393 		up_read(&group->list_mutex);
2394 		return;
2395 	}
2396 	snd_iprintf(buffer, msg);
2397 	list_for_each(p, &group->list_head) {
2398 		if (is_src)
2399 			s = list_entry(p, struct snd_seq_subscribers, src_list);
2400 		else
2401 			s = list_entry(p, struct snd_seq_subscribers, dest_list);
2402 		if (count++)
2403 			snd_iprintf(buffer, ", ");
2404 		snd_iprintf(buffer, "%d:%d",
2405 			    is_src ? s->info.dest.client : s->info.sender.client,
2406 			    is_src ? s->info.dest.port : s->info.sender.port);
2407 		if (s->info.flags & SNDRV_SEQ_PORT_SUBS_TIMESTAMP)
2408 			snd_iprintf(buffer, "[%c:%d]", ((s->info.flags & SNDRV_SEQ_PORT_SUBS_TIME_REAL) ? 'r' : 't'), s->info.queue);
2409 		if (group->exclusive)
2410 			snd_iprintf(buffer, "[ex]");
2411 	}
2412 	up_read(&group->list_mutex);
2413 	snd_iprintf(buffer, "\n");
2414 }
2415 
2416 #define FLAG_PERM_RD(perm) ((perm) & SNDRV_SEQ_PORT_CAP_READ ? ((perm) & SNDRV_SEQ_PORT_CAP_SUBS_READ ? 'R' : 'r') : '-')
2417 #define FLAG_PERM_WR(perm) ((perm) & SNDRV_SEQ_PORT_CAP_WRITE ? ((perm) & SNDRV_SEQ_PORT_CAP_SUBS_WRITE ? 'W' : 'w') : '-')
2418 #define FLAG_PERM_EX(perm) ((perm) & SNDRV_SEQ_PORT_CAP_NO_EXPORT ? '-' : 'e')
2419 
2420 #define FLAG_PERM_DUPLEX(perm) ((perm) & SNDRV_SEQ_PORT_CAP_DUPLEX ? 'X' : '-')
2421 
2422 static void snd_seq_info_dump_ports(struct snd_info_buffer *buffer,
2423 				    struct snd_seq_client *client)
2424 {
2425 	struct snd_seq_client_port *p;
2426 
2427 	mutex_lock(&client->ports_mutex);
2428 	list_for_each_entry(p, &client->ports_list_head, list) {
2429 		snd_iprintf(buffer, "  Port %3d : \"%s\" (%c%c%c%c)\n",
2430 			    p->addr.port, p->name,
2431 			    FLAG_PERM_RD(p->capability),
2432 			    FLAG_PERM_WR(p->capability),
2433 			    FLAG_PERM_EX(p->capability),
2434 			    FLAG_PERM_DUPLEX(p->capability));
2435 		snd_seq_info_dump_subscribers(buffer, &p->c_src, 1, "    Connecting To: ");
2436 		snd_seq_info_dump_subscribers(buffer, &p->c_dest, 0, "    Connected From: ");
2437 	}
2438 	mutex_unlock(&client->ports_mutex);
2439 }
2440 
2441 
2442 /* exported to seq_info.c */
2443 void snd_seq_info_clients_read(struct snd_info_entry *entry,
2444 			       struct snd_info_buffer *buffer)
2445 {
2446 	int c;
2447 	struct snd_seq_client *client;
2448 
2449 	snd_iprintf(buffer, "Client info\n");
2450 	snd_iprintf(buffer, "  cur  clients : %d\n", client_usage.cur);
2451 	snd_iprintf(buffer, "  peak clients : %d\n", client_usage.peak);
2452 	snd_iprintf(buffer, "  max  clients : %d\n", SNDRV_SEQ_MAX_CLIENTS);
2453 	snd_iprintf(buffer, "\n");
2454 
2455 	/* list the client table */
2456 	for (c = 0; c < SNDRV_SEQ_MAX_CLIENTS; c++) {
2457 		client = snd_seq_client_use_ptr(c);
2458 		if (client == NULL)
2459 			continue;
2460 		if (client->type == NO_CLIENT) {
2461 			snd_seq_client_unlock(client);
2462 			continue;
2463 		}
2464 
2465 		snd_iprintf(buffer, "Client %3d : \"%s\" [%s]\n",
2466 			    c, client->name,
2467 			    client->type == USER_CLIENT ? "User" : "Kernel");
2468 		snd_seq_info_dump_ports(buffer, client);
2469 		if (snd_seq_write_pool_allocated(client)) {
2470 			snd_iprintf(buffer, "  Output pool :\n");
2471 			snd_seq_info_pool(buffer, client->pool, "    ");
2472 		}
2473 		if (client->type == USER_CLIENT && client->data.user.fifo &&
2474 		    client->data.user.fifo->pool) {
2475 			snd_iprintf(buffer, "  Input pool :\n");
2476 			snd_seq_info_pool(buffer, client->data.user.fifo->pool, "    ");
2477 		}
2478 		snd_seq_client_unlock(client);
2479 	}
2480 }
2481 #endif /* CONFIG_SND_PROC_FS */
2482 
2483 /*---------------------------------------------------------------------------*/
2484 
2485 
2486 /*
2487  *  REGISTRATION PART
2488  */
2489 
2490 static const struct file_operations snd_seq_f_ops =
2491 {
2492 	.owner =	THIS_MODULE,
2493 	.read =		snd_seq_read,
2494 	.write =	snd_seq_write,
2495 	.open =		snd_seq_open,
2496 	.release =	snd_seq_release,
2497 	.llseek =	no_llseek,
2498 	.poll =		snd_seq_poll,
2499 	.unlocked_ioctl =	snd_seq_ioctl,
2500 	.compat_ioctl =	snd_seq_ioctl_compat,
2501 };
2502 
2503 static struct device seq_dev;
2504 
2505 /*
2506  * register sequencer device
2507  */
2508 int __init snd_sequencer_device_init(void)
2509 {
2510 	int err;
2511 
2512 	snd_device_initialize(&seq_dev, NULL);
2513 	dev_set_name(&seq_dev, "seq");
2514 
2515 	if (mutex_lock_interruptible(&register_mutex))
2516 		return -ERESTARTSYS;
2517 
2518 	err = snd_register_device(SNDRV_DEVICE_TYPE_SEQUENCER, NULL, 0,
2519 				  &snd_seq_f_ops, NULL, &seq_dev);
2520 	if (err < 0) {
2521 		mutex_unlock(&register_mutex);
2522 		put_device(&seq_dev);
2523 		return err;
2524 	}
2525 
2526 	mutex_unlock(&register_mutex);
2527 
2528 	return 0;
2529 }
2530 
2531 
2532 
2533 /*
2534  * unregister sequencer device
2535  */
2536 void __exit snd_sequencer_device_done(void)
2537 {
2538 	snd_unregister_device(&seq_dev);
2539 	put_device(&seq_dev);
2540 }
2541