xref: /linux/sound/core/seq/seq_clientmgr.c (revision 4bedea94545165364618d403d03b61d797acba0b)
1 /*
2  *  ALSA sequencer Client Manager
3  *  Copyright (c) 1998-2001 by Frank van de Pol <fvdpol@coil.demon.nl>
4  *                             Jaroslav Kysela <perex@suse.cz>
5  *                             Takashi Iwai <tiwai@suse.de>
6  *
7  *
8  *   This program is free software; you can redistribute it and/or modify
9  *   it under the terms of the GNU General Public License as published by
10  *   the Free Software Foundation; either version 2 of the License, or
11  *   (at your option) any later version.
12  *
13  *   This program is distributed in the hope that it will be useful,
14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *   GNU General Public License for more details.
17  *
18  *   You should have received a copy of the GNU General Public License
19  *   along with this program; if not, write to the Free Software
20  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
21  *
22  */
23 
24 #include <sound/driver.h>
25 #include <linux/init.h>
26 #include <linux/smp_lock.h>
27 #include <linux/slab.h>
28 #include <sound/core.h>
29 #include <sound/minors.h>
30 #include <linux/kmod.h>
31 
32 #include <sound/seq_kernel.h>
33 #include "seq_clientmgr.h"
34 #include "seq_memory.h"
35 #include "seq_queue.h"
36 #include "seq_timer.h"
37 #include "seq_info.h"
38 #include "seq_system.h"
39 #include <sound/seq_device.h>
40 #ifdef CONFIG_COMPAT
41 #include <linux/compat.h>
42 #endif
43 
44 /* Client Manager
45 
46  * this module handles the connections of userland and kernel clients
47  *
48  */
49 
50 #define SNDRV_SEQ_LFLG_INPUT	0x0001
51 #define SNDRV_SEQ_LFLG_OUTPUT	0x0002
52 #define SNDRV_SEQ_LFLG_OPEN	(SNDRV_SEQ_LFLG_INPUT|SNDRV_SEQ_LFLG_OUTPUT)
53 
54 static DEFINE_SPINLOCK(clients_lock);
55 static DECLARE_MUTEX(register_mutex);
56 
57 /*
58  * client table
59  */
60 static char clienttablock[SNDRV_SEQ_MAX_CLIENTS];
61 static client_t *clienttab[SNDRV_SEQ_MAX_CLIENTS];
62 static usage_t client_usage;
63 
64 /*
65  * prototypes
66  */
67 static int bounce_error_event(client_t *client, snd_seq_event_t *event, int err, int atomic, int hop);
68 static int snd_seq_deliver_single_event(client_t *client, snd_seq_event_t *event, int filter, int atomic, int hop);
69 
70 /*
71  */
72 
73 static inline mm_segment_t snd_enter_user(void)
74 {
75 	mm_segment_t fs = get_fs();
76 	set_fs(get_ds());
77 	return fs;
78 }
79 
80 static inline void snd_leave_user(mm_segment_t fs)
81 {
82 	set_fs(fs);
83 }
84 
85 /*
86  */
87 static inline unsigned short snd_seq_file_flags(struct file *file)
88 {
89         switch (file->f_mode & (FMODE_READ | FMODE_WRITE)) {
90         case FMODE_WRITE:
91                 return SNDRV_SEQ_LFLG_OUTPUT;
92         case FMODE_READ:
93                 return SNDRV_SEQ_LFLG_INPUT;
94         default:
95                 return SNDRV_SEQ_LFLG_OPEN;
96         }
97 }
98 
99 static inline int snd_seq_write_pool_allocated(client_t *client)
100 {
101 	return snd_seq_total_cells(client->pool) > 0;
102 }
103 
104 /* return pointer to client structure for specified id */
105 static client_t *clientptr(int clientid)
106 {
107 	if (clientid < 0 || clientid >= SNDRV_SEQ_MAX_CLIENTS) {
108 		snd_printd("Seq: oops. Trying to get pointer to client %d\n", clientid);
109 		return NULL;
110 	}
111 	return clienttab[clientid];
112 }
113 
114 extern int seq_client_load[];
115 
116 client_t *snd_seq_client_use_ptr(int clientid)
117 {
118 	unsigned long flags;
119 	client_t *client;
120 
121 	if (clientid < 0 || clientid >= SNDRV_SEQ_MAX_CLIENTS) {
122 		snd_printd("Seq: oops. Trying to get pointer to client %d\n", clientid);
123 		return NULL;
124 	}
125 	spin_lock_irqsave(&clients_lock, flags);
126 	client = clientptr(clientid);
127 	if (client)
128 		goto __lock;
129 	if (clienttablock[clientid]) {
130 		spin_unlock_irqrestore(&clients_lock, flags);
131 		return NULL;
132 	}
133 	spin_unlock_irqrestore(&clients_lock, flags);
134 #ifdef CONFIG_KMOD
135 	if (!in_interrupt() && current->fs->root) {
136 		static char client_requested[64];
137 		static char card_requested[SNDRV_CARDS];
138 		if (clientid < 64) {
139 			int idx;
140 
141 			if (! client_requested[clientid] && current->fs->root) {
142 				client_requested[clientid] = 1;
143 				for (idx = 0; idx < 64; idx++) {
144 					if (seq_client_load[idx] < 0)
145 						break;
146 					if (seq_client_load[idx] == clientid) {
147 						request_module("snd-seq-client-%i", clientid);
148 						break;
149 					}
150 				}
151 			}
152 		} else if (clientid >= 64 && clientid < 128) {
153 			int card = (clientid - 64) / 8;
154 			if (card < snd_ecards_limit) {
155 				if (! card_requested[card]) {
156 					card_requested[card] = 1;
157 					snd_request_card(card);
158 				}
159 				snd_seq_device_load_drivers();
160 			}
161 		}
162 		spin_lock_irqsave(&clients_lock, flags);
163 		client = clientptr(clientid);
164 		if (client)
165 			goto __lock;
166 		spin_unlock_irqrestore(&clients_lock, flags);
167 	}
168 #endif
169 	return NULL;
170 
171       __lock:
172 	snd_use_lock_use(&client->use_lock);
173 	spin_unlock_irqrestore(&clients_lock, flags);
174 	return client;
175 }
176 
177 static void usage_alloc(usage_t * res, int num)
178 {
179 	res->cur += num;
180 	if (res->cur > res->peak)
181 		res->peak = res->cur;
182 }
183 
184 static void usage_free(usage_t * res, int num)
185 {
186 	res->cur -= num;
187 }
188 
189 /* initialise data structures */
190 int __init client_init_data(void)
191 {
192 	/* zap out the client table */
193 	memset(&clienttablock, 0, sizeof(clienttablock));
194 	memset(&clienttab, 0, sizeof(clienttab));
195 	return 0;
196 }
197 
198 
199 static client_t *seq_create_client1(int client_index, int poolsize)
200 {
201 	unsigned long flags;
202 	int c;
203 	client_t *client;
204 
205 	/* init client data */
206 	client = kcalloc(1, sizeof(*client), GFP_KERNEL);
207 	if (client == NULL)
208 		return NULL;
209 	client->pool = snd_seq_pool_new(poolsize);
210 	if (client->pool == NULL) {
211 		kfree(client);
212 		return NULL;
213 	}
214 	client->type = NO_CLIENT;
215 	snd_use_lock_init(&client->use_lock);
216 	rwlock_init(&client->ports_lock);
217 	init_MUTEX(&client->ports_mutex);
218 	INIT_LIST_HEAD(&client->ports_list_head);
219 
220 	/* find free slot in the client table */
221 	spin_lock_irqsave(&clients_lock, flags);
222 	if (client_index < 0) {
223 		for (c = 128; c < SNDRV_SEQ_MAX_CLIENTS; c++) {
224 			if (clienttab[c] || clienttablock[c])
225 				continue;
226 			clienttab[client->number = c] = client;
227 			spin_unlock_irqrestore(&clients_lock, flags);
228 			return client;
229 		}
230 	} else {
231 		if (clienttab[client_index] == NULL && !clienttablock[client_index]) {
232 			clienttab[client->number = client_index] = client;
233 			spin_unlock_irqrestore(&clients_lock, flags);
234 			return client;
235 		}
236 	}
237 	spin_unlock_irqrestore(&clients_lock, flags);
238 	snd_seq_pool_delete(&client->pool);
239 	kfree(client);
240 	return NULL;	/* no free slot found or busy, return failure code */
241 }
242 
243 
244 static int seq_free_client1(client_t *client)
245 {
246 	unsigned long flags;
247 
248 	snd_assert(client != NULL, return -EINVAL);
249 	snd_seq_delete_all_ports(client);
250 	snd_seq_queue_client_leave(client->number);
251 	spin_lock_irqsave(&clients_lock, flags);
252 	clienttablock[client->number] = 1;
253 	clienttab[client->number] = NULL;
254 	spin_unlock_irqrestore(&clients_lock, flags);
255 	snd_use_lock_sync(&client->use_lock);
256 	snd_seq_queue_client_termination(client->number);
257 	if (client->pool)
258 		snd_seq_pool_delete(&client->pool);
259 	spin_lock_irqsave(&clients_lock, flags);
260 	clienttablock[client->number] = 0;
261 	spin_unlock_irqrestore(&clients_lock, flags);
262 	return 0;
263 }
264 
265 
266 static void seq_free_client(client_t * client)
267 {
268 	down(&register_mutex);
269 	switch (client->type) {
270 	case NO_CLIENT:
271 		snd_printk(KERN_WARNING "Seq: Trying to free unused client %d\n", client->number);
272 		break;
273 	case USER_CLIENT:
274 	case KERNEL_CLIENT:
275 		seq_free_client1(client);
276 		usage_free(&client_usage, 1);
277 		break;
278 
279 	default:
280 		snd_printk(KERN_ERR "Seq: Trying to free client %d with undefined type = %d\n", client->number, client->type);
281 	}
282 	up(&register_mutex);
283 
284 	snd_seq_system_client_ev_client_exit(client->number);
285 }
286 
287 
288 
289 /* -------------------------------------------------------- */
290 
291 /* create a user client */
292 static int snd_seq_open(struct inode *inode, struct file *file)
293 {
294 	int c, mode;			/* client id */
295 	client_t *client;
296 	user_client_t *user;
297 
298 	if (down_interruptible(&register_mutex))
299 		return -ERESTARTSYS;
300 	client = seq_create_client1(-1, SNDRV_SEQ_DEFAULT_EVENTS);
301 	if (client == NULL) {
302 		up(&register_mutex);
303 		return -ENOMEM;	/* failure code */
304 	}
305 
306 	mode = snd_seq_file_flags(file);
307 	if (mode & SNDRV_SEQ_LFLG_INPUT)
308 		client->accept_input = 1;
309 	if (mode & SNDRV_SEQ_LFLG_OUTPUT)
310 		client->accept_output = 1;
311 
312 	user = &client->data.user;
313 	user->fifo = NULL;
314 	user->fifo_pool_size = 0;
315 
316 	if (mode & SNDRV_SEQ_LFLG_INPUT) {
317 		user->fifo_pool_size = SNDRV_SEQ_DEFAULT_CLIENT_EVENTS;
318 		user->fifo = snd_seq_fifo_new(user->fifo_pool_size);
319 		if (user->fifo == NULL) {
320 			seq_free_client1(client);
321 			kfree(client);
322 			up(&register_mutex);
323 			return -ENOMEM;
324 		}
325 	}
326 
327 	usage_alloc(&client_usage, 1);
328 	client->type = USER_CLIENT;
329 	up(&register_mutex);
330 
331 	c = client->number;
332 	file->private_data = client;
333 
334 	/* fill client data */
335 	user->file = file;
336 	sprintf(client->name, "Client-%d", c);
337 
338 	/* make others aware this new client */
339 	snd_seq_system_client_ev_client_start(c);
340 
341 	return 0;
342 }
343 
344 /* delete a user client */
345 static int snd_seq_release(struct inode *inode, struct file *file)
346 {
347 	client_t *client = (client_t *) file->private_data;
348 
349 	if (client) {
350 		seq_free_client(client);
351 		if (client->data.user.fifo)
352 			snd_seq_fifo_delete(&client->data.user.fifo);
353 		kfree(client);
354 	}
355 
356 	return 0;
357 }
358 
359 
360 /* handle client read() */
361 /* possible error values:
362  *	-ENXIO	invalid client or file open mode
363  *	-ENOSPC	FIFO overflow (the flag is cleared after this error report)
364  *	-EINVAL	no enough user-space buffer to write the whole event
365  *	-EFAULT	seg. fault during copy to user space
366  */
367 static ssize_t snd_seq_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
368 {
369 	client_t *client = (client_t *) file->private_data;
370 	fifo_t *fifo;
371 	int err;
372 	long result = 0;
373 	snd_seq_event_cell_t *cell;
374 
375 	if (!(snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_INPUT))
376 		return -ENXIO;
377 
378 	if (!access_ok(VERIFY_WRITE, buf, count))
379 		return -EFAULT;
380 
381 	/* check client structures are in place */
382 	snd_assert(client != NULL, return -ENXIO);
383 
384 	if (!client->accept_input || (fifo = client->data.user.fifo) == NULL)
385 		return -ENXIO;
386 
387 	if (atomic_read(&fifo->overflow) > 0) {
388 		/* buffer overflow is detected */
389 		snd_seq_fifo_clear(fifo);
390 		/* return error code */
391 		return -ENOSPC;
392 	}
393 
394 	cell = NULL;
395 	err = 0;
396 	snd_seq_fifo_lock(fifo);
397 
398 	/* while data available in queue */
399 	while (count >= sizeof(snd_seq_event_t)) {
400 		int nonblock;
401 
402 		nonblock = (file->f_flags & O_NONBLOCK) || result > 0;
403 		if ((err = snd_seq_fifo_cell_out(fifo, &cell, nonblock)) < 0) {
404 			break;
405 		}
406 		if (snd_seq_ev_is_variable(&cell->event)) {
407 			snd_seq_event_t tmpev;
408 			tmpev = cell->event;
409 			tmpev.data.ext.len &= ~SNDRV_SEQ_EXT_MASK;
410 			if (copy_to_user(buf, &tmpev, sizeof(snd_seq_event_t))) {
411 				err = -EFAULT;
412 				break;
413 			}
414 			count -= sizeof(snd_seq_event_t);
415 			buf += sizeof(snd_seq_event_t);
416 			err = snd_seq_expand_var_event(&cell->event, count, (char *)buf, 0, sizeof(snd_seq_event_t));
417 			if (err < 0)
418 				break;
419 			result += err;
420 			count -= err;
421 			buf += err;
422 		} else {
423 			if (copy_to_user(buf, &cell->event, sizeof(snd_seq_event_t))) {
424 				err = -EFAULT;
425 				break;
426 			}
427 			count -= sizeof(snd_seq_event_t);
428 			buf += sizeof(snd_seq_event_t);
429 		}
430 		snd_seq_cell_free(cell);
431 		cell = NULL; /* to be sure */
432 		result += sizeof(snd_seq_event_t);
433 	}
434 
435 	if (err < 0) {
436 		if (cell)
437 			snd_seq_fifo_cell_putback(fifo, cell);
438 		if (err == -EAGAIN && result > 0)
439 			err = 0;
440 	}
441 	snd_seq_fifo_unlock(fifo);
442 
443 	return (err < 0) ? err : result;
444 }
445 
446 
447 /*
448  * check access permission to the port
449  */
450 static int check_port_perm(client_port_t *port, unsigned int flags)
451 {
452 	if ((port->capability & flags) != flags)
453 		return 0;
454 	return flags;
455 }
456 
457 /*
458  * check if the destination client is available, and return the pointer
459  * if filter is non-zero, client filter bitmap is tested.
460  */
461 static client_t *get_event_dest_client(snd_seq_event_t *event, int filter)
462 {
463 	client_t *dest;
464 
465 	dest = snd_seq_client_use_ptr(event->dest.client);
466 	if (dest == NULL)
467 		return NULL;
468 	if (! dest->accept_input)
469 		goto __not_avail;
470 	if ((dest->filter & SNDRV_SEQ_FILTER_USE_EVENT) &&
471 	    ! test_bit(event->type, dest->event_filter))
472 		goto __not_avail;
473 	if (filter && !(dest->filter & filter))
474 		goto __not_avail;
475 
476 	return dest; /* ok - accessible */
477 __not_avail:
478 	snd_seq_client_unlock(dest);
479 	return NULL;
480 }
481 
482 
483 /*
484  * Return the error event.
485  *
486  * If the receiver client is a user client, the original event is
487  * encapsulated in SNDRV_SEQ_EVENT_BOUNCE as variable length event.  If
488  * the original event is also variable length, the external data is
489  * copied after the event record.
490  * If the receiver client is a kernel client, the original event is
491  * quoted in SNDRV_SEQ_EVENT_KERNEL_ERROR, since this requires no extra
492  * kmalloc.
493  */
494 static int bounce_error_event(client_t *client, snd_seq_event_t *event,
495 			      int err, int atomic, int hop)
496 {
497 	snd_seq_event_t bounce_ev;
498 	int result;
499 
500 	if (client == NULL ||
501 	    ! (client->filter & SNDRV_SEQ_FILTER_BOUNCE) ||
502 	    ! client->accept_input)
503 		return 0; /* ignored */
504 
505 	/* set up quoted error */
506 	memset(&bounce_ev, 0, sizeof(bounce_ev));
507 	bounce_ev.type = SNDRV_SEQ_EVENT_KERNEL_ERROR;
508 	bounce_ev.flags = SNDRV_SEQ_EVENT_LENGTH_FIXED;
509 	bounce_ev.queue = SNDRV_SEQ_QUEUE_DIRECT;
510 	bounce_ev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
511 	bounce_ev.source.port = SNDRV_SEQ_PORT_SYSTEM_ANNOUNCE;
512 	bounce_ev.dest.client = client->number;
513 	bounce_ev.dest.port = event->source.port;
514 	bounce_ev.data.quote.origin = event->dest;
515 	bounce_ev.data.quote.event = event;
516 	bounce_ev.data.quote.value = -err; /* use positive value */
517 	result = snd_seq_deliver_single_event(NULL, &bounce_ev, 0, atomic, hop + 1);
518 	if (result < 0) {
519 		client->event_lost++;
520 		return result;
521 	}
522 
523 	return result;
524 }
525 
526 
527 /*
528  * rewrite the time-stamp of the event record with the curren time
529  * of the given queue.
530  * return non-zero if updated.
531  */
532 static int update_timestamp_of_queue(snd_seq_event_t *event, int queue, int real_time)
533 {
534 	queue_t *q;
535 
536 	q = queueptr(queue);
537 	if (! q)
538 		return 0;
539 	event->queue = queue;
540 	event->flags &= ~SNDRV_SEQ_TIME_STAMP_MASK;
541 	if (real_time) {
542 		event->time.time = snd_seq_timer_get_cur_time(q->timer);
543 		event->flags |= SNDRV_SEQ_TIME_STAMP_REAL;
544 	} else {
545 		event->time.tick = snd_seq_timer_get_cur_tick(q->timer);
546 		event->flags |= SNDRV_SEQ_TIME_STAMP_TICK;
547 	}
548 	queuefree(q);
549 	return 1;
550 }
551 
552 
553 /*
554  * deliver an event to the specified destination.
555  * if filter is non-zero, client filter bitmap is tested.
556  *
557  *  RETURN VALUE: 0 : if succeeded
558  *		 <0 : error
559  */
560 static int snd_seq_deliver_single_event(client_t *client,
561 					snd_seq_event_t *event,
562 					int filter, int atomic, int hop)
563 {
564 	client_t *dest = NULL;
565 	client_port_t *dest_port = NULL;
566 	int result = -ENOENT;
567 	int direct;
568 
569 	direct = snd_seq_ev_is_direct(event);
570 
571 	dest = get_event_dest_client(event, filter);
572 	if (dest == NULL)
573 		goto __skip;
574 	dest_port = snd_seq_port_use_ptr(dest, event->dest.port);
575 	if (dest_port == NULL)
576 		goto __skip;
577 
578 	/* check permission */
579 	if (! check_port_perm(dest_port, SNDRV_SEQ_PORT_CAP_WRITE)) {
580 		result = -EPERM;
581 		goto __skip;
582 	}
583 
584 	if (dest_port->timestamping)
585 		update_timestamp_of_queue(event, dest_port->time_queue,
586 					  dest_port->time_real);
587 
588 	switch (dest->type) {
589 	case USER_CLIENT:
590 		if (dest->data.user.fifo)
591 			result = snd_seq_fifo_event_in(dest->data.user.fifo, event);
592 		break;
593 
594 	case KERNEL_CLIENT:
595 		if (dest_port->event_input == NULL)
596 			break;
597 		result = dest_port->event_input(event, direct, dest_port->private_data, atomic, hop);
598 		break;
599 	default:
600 		break;
601 	}
602 
603   __skip:
604 	if (dest_port)
605 		snd_seq_port_unlock(dest_port);
606 	if (dest)
607 		snd_seq_client_unlock(dest);
608 
609 	if (result < 0 && !direct) {
610 		result = bounce_error_event(client, event, result, atomic, hop);
611 	}
612 	return result;
613 }
614 
615 
616 /*
617  * send the event to all subscribers:
618  */
619 static int deliver_to_subscribers(client_t *client,
620 				  snd_seq_event_t *event,
621 				  int atomic, int hop)
622 {
623 	subscribers_t *subs;
624 	int err = 0, num_ev = 0;
625 	snd_seq_event_t event_saved;
626 	client_port_t *src_port;
627 	struct list_head *p;
628 	port_subs_info_t *grp;
629 
630 	src_port = snd_seq_port_use_ptr(client, event->source.port);
631 	if (src_port == NULL)
632 		return -EINVAL; /* invalid source port */
633 	/* save original event record */
634 	event_saved = *event;
635 	grp = &src_port->c_src;
636 
637 	/* lock list */
638 	if (atomic)
639 		read_lock(&grp->list_lock);
640 	else
641 		down_read(&grp->list_mutex);
642 	list_for_each(p, &grp->list_head) {
643 		subs = list_entry(p, subscribers_t, src_list);
644 		event->dest = subs->info.dest;
645 		if (subs->info.flags & SNDRV_SEQ_PORT_SUBS_TIMESTAMP)
646 			/* convert time according to flag with subscription */
647 			update_timestamp_of_queue(event, subs->info.queue,
648 						  subs->info.flags & SNDRV_SEQ_PORT_SUBS_TIME_REAL);
649 		err = snd_seq_deliver_single_event(client, event,
650 						   0, atomic, hop);
651 		if (err < 0)
652 			break;
653 		num_ev++;
654 		/* restore original event record */
655 		*event = event_saved;
656 	}
657 	if (atomic)
658 		read_unlock(&grp->list_lock);
659 	else
660 		up_read(&grp->list_mutex);
661 	*event = event_saved; /* restore */
662 	snd_seq_port_unlock(src_port);
663 	return (err < 0) ? err : num_ev;
664 }
665 
666 
667 #ifdef SUPPORT_BROADCAST
668 /*
669  * broadcast to all ports:
670  */
671 static int port_broadcast_event(client_t *client,
672 				snd_seq_event_t *event,
673 				int atomic, int hop)
674 {
675 	int num_ev = 0, err = 0;
676 	client_t *dest_client;
677 	struct list_head *p;
678 
679 	dest_client = get_event_dest_client(event, SNDRV_SEQ_FILTER_BROADCAST);
680 	if (dest_client == NULL)
681 		return 0; /* no matching destination */
682 
683 	read_lock(&dest_client->ports_lock);
684 	list_for_each(p, &dest_client->ports_list_head) {
685 		client_port_t *port = list_entry(p, client_port_t, list);
686 		event->dest.port = port->addr.port;
687 		/* pass NULL as source client to avoid error bounce */
688 		err = snd_seq_deliver_single_event(NULL, event,
689 						   SNDRV_SEQ_FILTER_BROADCAST,
690 						   atomic, hop);
691 		if (err < 0)
692 			break;
693 		num_ev++;
694 	}
695 	read_unlock(&dest_client->ports_lock);
696 	snd_seq_client_unlock(dest_client);
697 	event->dest.port = SNDRV_SEQ_ADDRESS_BROADCAST; /* restore */
698 	return (err < 0) ? err : num_ev;
699 }
700 
701 /*
702  * send the event to all clients:
703  * if destination port is also ADDRESS_BROADCAST, deliver to all ports.
704  */
705 static int broadcast_event(client_t *client,
706 			   snd_seq_event_t *event, int atomic, int hop)
707 {
708 	int err = 0, num_ev = 0;
709 	int dest;
710 	snd_seq_addr_t addr;
711 
712 	addr = event->dest; /* save */
713 
714 	for (dest = 0; dest < SNDRV_SEQ_MAX_CLIENTS; dest++) {
715 		/* don't send to itself */
716 		if (dest == client->number)
717 			continue;
718 		event->dest.client = dest;
719 		event->dest.port = addr.port;
720 		if (addr.port == SNDRV_SEQ_ADDRESS_BROADCAST)
721 			err = port_broadcast_event(client, event, atomic, hop);
722 		else
723 			/* pass NULL as source client to avoid error bounce */
724 			err = snd_seq_deliver_single_event(NULL, event,
725 							   SNDRV_SEQ_FILTER_BROADCAST,
726 							   atomic, hop);
727 		if (err < 0)
728 			break;
729 		num_ev += err;
730 	}
731 	event->dest = addr; /* restore */
732 	return (err < 0) ? err : num_ev;
733 }
734 
735 
736 /* multicast - not supported yet */
737 static int multicast_event(client_t *client, snd_seq_event_t *event,
738 			   int atomic, int hop)
739 {
740 	snd_printd("seq: multicast not supported yet.\n");
741 	return 0; /* ignored */
742 }
743 #endif /* SUPPORT_BROADCAST */
744 
745 
746 /* deliver an event to the destination port(s).
747  * if the event is to subscribers or broadcast, the event is dispatched
748  * to multiple targets.
749  *
750  * RETURN VALUE: n > 0  : the number of delivered events.
751  *               n == 0 : the event was not passed to any client.
752  *               n < 0  : error - event was not processed.
753  */
754 static int snd_seq_deliver_event(client_t *client, snd_seq_event_t *event,
755 				 int atomic, int hop)
756 {
757 	int result;
758 
759 	hop++;
760 	if (hop >= SNDRV_SEQ_MAX_HOPS) {
761 		snd_printd("too long delivery path (%d:%d->%d:%d)\n",
762 			   event->source.client, event->source.port,
763 			   event->dest.client, event->dest.port);
764 		return -EMLINK;
765 	}
766 
767 	if (event->queue == SNDRV_SEQ_ADDRESS_SUBSCRIBERS ||
768 	    event->dest.client == SNDRV_SEQ_ADDRESS_SUBSCRIBERS)
769 		result = deliver_to_subscribers(client, event, atomic, hop);
770 #ifdef SUPPORT_BROADCAST
771 	else if (event->queue == SNDRV_SEQ_ADDRESS_BROADCAST ||
772 		 event->dest.client == SNDRV_SEQ_ADDRESS_BROADCAST)
773 		result = broadcast_event(client, event, atomic, hop);
774 	else if (event->dest.client >= SNDRV_SEQ_MAX_CLIENTS)
775 		result = multicast_event(client, event, atomic, hop);
776 	else if (event->dest.port == SNDRV_SEQ_ADDRESS_BROADCAST)
777 		result = port_broadcast_event(client, event, atomic, hop);
778 #endif
779 	else
780 		result = snd_seq_deliver_single_event(client, event, 0, atomic, hop);
781 
782 	return result;
783 }
784 
785 /*
786  * dispatch an event cell:
787  * This function is called only from queue check routines in timer
788  * interrupts or after enqueued.
789  * The event cell shall be released or re-queued in this function.
790  *
791  * RETURN VALUE: n > 0  : the number of delivered events.
792  *		 n == 0 : the event was not passed to any client.
793  *		 n < 0  : error - event was not processed.
794  */
795 int snd_seq_dispatch_event(snd_seq_event_cell_t *cell, int atomic, int hop)
796 {
797 	client_t *client;
798 	int result;
799 
800 	snd_assert(cell != NULL, return -EINVAL);
801 
802 	client = snd_seq_client_use_ptr(cell->event.source.client);
803 	if (client == NULL) {
804 		snd_seq_cell_free(cell); /* release this cell */
805 		return -EINVAL;
806 	}
807 
808 	if (cell->event.type == SNDRV_SEQ_EVENT_NOTE) {
809 		/* NOTE event:
810 		 * the event cell is re-used as a NOTE-OFF event and
811 		 * enqueued again.
812 		 */
813 		snd_seq_event_t tmpev, *ev;
814 
815 		/* reserve this event to enqueue note-off later */
816 		tmpev = cell->event;
817 		tmpev.type = SNDRV_SEQ_EVENT_NOTEON;
818 		result = snd_seq_deliver_event(client, &tmpev, atomic, hop);
819 
820 		/*
821 		 * This was originally a note event.  We now re-use the
822 		 * cell for the note-off event.
823 		 */
824 
825 		ev = &cell->event;
826 		ev->type = SNDRV_SEQ_EVENT_NOTEOFF;
827 		ev->flags |= SNDRV_SEQ_PRIORITY_HIGH;
828 
829 		/* add the duration time */
830 		switch (ev->flags & SNDRV_SEQ_TIME_STAMP_MASK) {
831 		case SNDRV_SEQ_TIME_STAMP_TICK:
832 			ev->time.tick += ev->data.note.duration;
833 			break;
834 		case SNDRV_SEQ_TIME_STAMP_REAL:
835 			/* unit for duration is ms */
836 			ev->time.time.tv_nsec += 1000000 * (ev->data.note.duration % 1000);
837 			ev->time.time.tv_sec += ev->data.note.duration / 1000 +
838 						ev->time.time.tv_nsec / 1000000000;
839 			ev->time.time.tv_nsec %= 1000000000;
840 			break;
841 		}
842 		ev->data.note.velocity = ev->data.note.off_velocity;
843 
844 		/* Now queue this cell as the note off event */
845 		if (snd_seq_enqueue_event(cell, atomic, hop) < 0)
846 			snd_seq_cell_free(cell); /* release this cell */
847 
848 	} else {
849 		/* Normal events:
850 		 * event cell is freed after processing the event
851 		 */
852 
853 		result = snd_seq_deliver_event(client, &cell->event, atomic, hop);
854 		snd_seq_cell_free(cell);
855 	}
856 
857 	snd_seq_client_unlock(client);
858 	return result;
859 }
860 
861 
862 /* Allocate a cell from client pool and enqueue it to queue:
863  * if pool is empty and blocking is TRUE, sleep until a new cell is
864  * available.
865  */
866 static int snd_seq_client_enqueue_event(client_t *client,
867 					snd_seq_event_t *event,
868 					struct file *file, int blocking,
869 					int atomic, int hop)
870 {
871 	snd_seq_event_cell_t *cell;
872 	int err;
873 
874 	/* special queue values - force direct passing */
875 	if (event->queue == SNDRV_SEQ_ADDRESS_SUBSCRIBERS) {
876 		event->dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
877 		event->queue = SNDRV_SEQ_QUEUE_DIRECT;
878 	} else
879 #ifdef SUPPORT_BROADCAST
880 		if (event->queue == SNDRV_SEQ_ADDRESS_BROADCAST) {
881 			event->dest.client = SNDRV_SEQ_ADDRESS_BROADCAST;
882 			event->queue = SNDRV_SEQ_QUEUE_DIRECT;
883 		}
884 #endif
885 	if (event->dest.client == SNDRV_SEQ_ADDRESS_SUBSCRIBERS) {
886 		/* check presence of source port */
887 		client_port_t *src_port = snd_seq_port_use_ptr(client, event->source.port);
888 		if (src_port == NULL)
889 			return -EINVAL;
890 		snd_seq_port_unlock(src_port);
891 	}
892 
893 	/* direct event processing without enqueued */
894 	if (snd_seq_ev_is_direct(event)) {
895 		if (event->type == SNDRV_SEQ_EVENT_NOTE)
896 			return -EINVAL; /* this event must be enqueued! */
897 		return snd_seq_deliver_event(client, event, atomic, hop);
898 	}
899 
900 	/* Not direct, normal queuing */
901 	if (snd_seq_queue_is_used(event->queue, client->number) <= 0)
902 		return -EINVAL;  /* invalid queue */
903 	if (! snd_seq_write_pool_allocated(client))
904 		return -ENXIO; /* queue is not allocated */
905 
906 	/* allocate an event cell */
907 	err = snd_seq_event_dup(client->pool, event, &cell, !blocking || atomic, file);
908 	if (err < 0)
909 		return err;
910 
911 	/* we got a cell. enqueue it. */
912 	if ((err = snd_seq_enqueue_event(cell, atomic, hop)) < 0) {
913 		snd_seq_cell_free(cell);
914 		return err;
915 	}
916 
917 	return 0;
918 }
919 
920 
921 /*
922  * check validity of event type and data length.
923  * return non-zero if invalid.
924  */
925 static int check_event_type_and_length(snd_seq_event_t *ev)
926 {
927 	switch (snd_seq_ev_length_type(ev)) {
928 	case SNDRV_SEQ_EVENT_LENGTH_FIXED:
929 		if (snd_seq_ev_is_variable_type(ev))
930 			return -EINVAL;
931 		break;
932 	case SNDRV_SEQ_EVENT_LENGTH_VARIABLE:
933 		if (! snd_seq_ev_is_variable_type(ev) ||
934 		    (ev->data.ext.len & ~SNDRV_SEQ_EXT_MASK) >= SNDRV_SEQ_MAX_EVENT_LEN)
935 			return -EINVAL;
936 		break;
937 	case SNDRV_SEQ_EVENT_LENGTH_VARUSR:
938 		if (! snd_seq_ev_is_instr_type(ev) ||
939 		    ! snd_seq_ev_is_direct(ev))
940 			return -EINVAL;
941 		break;
942 	}
943 	return 0;
944 }
945 
946 
947 /* handle write() */
948 /* possible error values:
949  *	-ENXIO	invalid client or file open mode
950  *	-ENOMEM	malloc failed
951  *	-EFAULT	seg. fault during copy from user space
952  *	-EINVAL	invalid event
953  *	-EAGAIN	no space in output pool
954  *	-EINTR	interrupts while sleep
955  *	-EMLINK	too many hops
956  *	others	depends on return value from driver callback
957  */
958 static ssize_t snd_seq_write(struct file *file, const char __user *buf, size_t count, loff_t *offset)
959 {
960 	client_t *client = (client_t *) file->private_data;
961 	int written = 0, len;
962 	int err = -EINVAL;
963 	snd_seq_event_t event;
964 
965 	if (!(snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_OUTPUT))
966 		return -ENXIO;
967 
968 	/* check client structures are in place */
969 	snd_assert(client != NULL, return -ENXIO);
970 
971 	if (!client->accept_output || client->pool == NULL)
972 		return -ENXIO;
973 
974 	/* allocate the pool now if the pool is not allocated yet */
975 	if (client->pool->size > 0 && !snd_seq_write_pool_allocated(client)) {
976 		if (snd_seq_pool_init(client->pool) < 0)
977 			return -ENOMEM;
978 	}
979 
980 	/* only process whole events */
981 	while (count >= sizeof(snd_seq_event_t)) {
982 		/* Read in the event header from the user */
983 		len = sizeof(event);
984 		if (copy_from_user(&event, buf, len)) {
985 			err = -EFAULT;
986 			break;
987 		}
988 		event.source.client = client->number;	/* fill in client number */
989 		/* Check for extension data length */
990 		if (check_event_type_and_length(&event)) {
991 			err = -EINVAL;
992 			break;
993 		}
994 
995 		/* check for special events */
996 		if (event.type == SNDRV_SEQ_EVENT_NONE)
997 			goto __skip_event;
998 		else if (snd_seq_ev_is_reserved(&event)) {
999 			err = -EINVAL;
1000 			break;
1001 		}
1002 
1003 		if (snd_seq_ev_is_variable(&event)) {
1004 			int extlen = event.data.ext.len & ~SNDRV_SEQ_EXT_MASK;
1005 			if ((size_t)(extlen + len) > count) {
1006 				/* back out, will get an error this time or next */
1007 				err = -EINVAL;
1008 				break;
1009 			}
1010 			/* set user space pointer */
1011 			event.data.ext.len = extlen | SNDRV_SEQ_EXT_USRPTR;
1012 			event.data.ext.ptr = (char*)buf + sizeof(snd_seq_event_t);
1013 			len += extlen; /* increment data length */
1014 		} else {
1015 #ifdef CONFIG_COMPAT
1016 			if (client->convert32 && snd_seq_ev_is_varusr(&event)) {
1017 				void *ptr = compat_ptr(event.data.raw32.d[1]);
1018 				event.data.ext.ptr = ptr;
1019 			}
1020 #endif
1021 		}
1022 
1023 		/* ok, enqueue it */
1024 		err = snd_seq_client_enqueue_event(client, &event, file,
1025 						   !(file->f_flags & O_NONBLOCK),
1026 						   0, 0);
1027 		if (err < 0)
1028 			break;
1029 
1030 	__skip_event:
1031 		/* Update pointers and counts */
1032 		count -= len;
1033 		buf += len;
1034 		written += len;
1035 	}
1036 
1037 	return written ? written : err;
1038 }
1039 
1040 
1041 /*
1042  * handle polling
1043  */
1044 static unsigned int snd_seq_poll(struct file *file, poll_table * wait)
1045 {
1046 	client_t *client = (client_t *) file->private_data;
1047 	unsigned int mask = 0;
1048 
1049 	/* check client structures are in place */
1050 	snd_assert(client != NULL, return -ENXIO);
1051 
1052 	if ((snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_INPUT) &&
1053 	    client->data.user.fifo) {
1054 
1055 		/* check if data is available in the outqueue */
1056 		if (snd_seq_fifo_poll_wait(client->data.user.fifo, file, wait))
1057 			mask |= POLLIN | POLLRDNORM;
1058 	}
1059 
1060 	if (snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_OUTPUT) {
1061 
1062 		/* check if data is available in the pool */
1063 		if (!snd_seq_write_pool_allocated(client) ||
1064 		    snd_seq_pool_poll_wait(client->pool, file, wait))
1065 			mask |= POLLOUT | POLLWRNORM;
1066 	}
1067 
1068 	return mask;
1069 }
1070 
1071 
1072 /*-----------------------------------------------------*/
1073 
1074 
1075 /* SYSTEM_INFO ioctl() */
1076 static int snd_seq_ioctl_system_info(client_t *client, void __user *arg)
1077 {
1078 	snd_seq_system_info_t info;
1079 
1080 	memset(&info, 0, sizeof(info));
1081 	/* fill the info fields */
1082 	info.queues = SNDRV_SEQ_MAX_QUEUES;
1083 	info.clients = SNDRV_SEQ_MAX_CLIENTS;
1084 	info.ports = 256;	/* fixed limit */
1085 	info.channels = 256;	/* fixed limit */
1086 	info.cur_clients = client_usage.cur;
1087 	info.cur_queues = snd_seq_queue_get_cur_queues();
1088 
1089 	if (copy_to_user(arg, &info, sizeof(info)))
1090 		return -EFAULT;
1091 	return 0;
1092 }
1093 
1094 
1095 /* RUNNING_MODE ioctl() */
1096 static int snd_seq_ioctl_running_mode(client_t *client, void __user *arg)
1097 {
1098 	struct sndrv_seq_running_info info;
1099 	client_t *cptr;
1100 	int err = 0;
1101 
1102 	if (copy_from_user(&info, arg, sizeof(info)))
1103 		return -EFAULT;
1104 
1105 	/* requested client number */
1106 	cptr = snd_seq_client_use_ptr(info.client);
1107 	if (cptr == NULL)
1108 		return -ENOENT;		/* don't change !!! */
1109 
1110 #ifdef SNDRV_BIG_ENDIAN
1111 	if (! info.big_endian) {
1112 		err = -EINVAL;
1113 		goto __err;
1114 	}
1115 #else
1116 	if (info.big_endian) {
1117 		err = -EINVAL;
1118 		goto __err;
1119 	}
1120 
1121 #endif
1122 	if (info.cpu_mode > sizeof(long)) {
1123 		err = -EINVAL;
1124 		goto __err;
1125 	}
1126 	cptr->convert32 = (info.cpu_mode < sizeof(long));
1127  __err:
1128 	snd_seq_client_unlock(cptr);
1129 	return err;
1130 }
1131 
1132 /* CLIENT_INFO ioctl() */
1133 static void get_client_info(client_t *cptr, snd_seq_client_info_t *info)
1134 {
1135 	info->client = cptr->number;
1136 
1137 	/* fill the info fields */
1138 	info->type = cptr->type;
1139 	strcpy(info->name, cptr->name);
1140 	info->filter = cptr->filter;
1141 	info->event_lost = cptr->event_lost;
1142 	memcpy(info->event_filter, cptr->event_filter, 32);
1143 	info->num_ports = cptr->num_ports;
1144 	memset(info->reserved, 0, sizeof(info->reserved));
1145 }
1146 
1147 static int snd_seq_ioctl_get_client_info(client_t * client, void __user *arg)
1148 {
1149 	client_t *cptr;
1150 	snd_seq_client_info_t client_info;
1151 
1152 	if (copy_from_user(&client_info, arg, sizeof(client_info)))
1153 		return -EFAULT;
1154 
1155 	/* requested client number */
1156 	cptr = snd_seq_client_use_ptr(client_info.client);
1157 	if (cptr == NULL)
1158 		return -ENOENT;		/* don't change !!! */
1159 
1160 	get_client_info(cptr, &client_info);
1161 	snd_seq_client_unlock(cptr);
1162 
1163 	if (copy_to_user(arg, &client_info, sizeof(client_info)))
1164 		return -EFAULT;
1165 	return 0;
1166 }
1167 
1168 
1169 /* CLIENT_INFO ioctl() */
1170 static int snd_seq_ioctl_set_client_info(client_t * client, void __user *arg)
1171 {
1172 	snd_seq_client_info_t client_info;
1173 
1174 	if (copy_from_user(&client_info, arg, sizeof(client_info)))
1175 		return -EFAULT;
1176 
1177 	/* it is not allowed to set the info fields for an another client */
1178 	if (client->number != client_info.client)
1179 		return -EPERM;
1180 	/* also client type must be set now */
1181 	if (client->type != client_info.type)
1182 		return -EINVAL;
1183 
1184 	/* fill the info fields */
1185 	if (client_info.name[0])
1186 		strlcpy(client->name, client_info.name, sizeof(client->name));
1187 
1188 	client->filter = client_info.filter;
1189 	client->event_lost = client_info.event_lost;
1190 	memcpy(client->event_filter, client_info.event_filter, 32);
1191 
1192 	return 0;
1193 }
1194 
1195 
1196 /*
1197  * CREATE PORT ioctl()
1198  */
1199 static int snd_seq_ioctl_create_port(client_t * client, void __user *arg)
1200 {
1201 	client_port_t *port;
1202 	snd_seq_port_info_t info;
1203 	snd_seq_port_callback_t *callback;
1204 
1205 	if (copy_from_user(&info, arg, sizeof(info)))
1206 		return -EFAULT;
1207 
1208 	/* it is not allowed to create the port for an another client */
1209 	if (info.addr.client != client->number)
1210 		return -EPERM;
1211 
1212 	port = snd_seq_create_port(client, (info.flags & SNDRV_SEQ_PORT_FLG_GIVEN_PORT) ? info.addr.port : -1);
1213 	if (port == NULL)
1214 		return -ENOMEM;
1215 
1216 	if (client->type == USER_CLIENT && info.kernel) {
1217 		snd_seq_delete_port(client, port->addr.port);
1218 		return -EINVAL;
1219 	}
1220 	if (client->type == KERNEL_CLIENT) {
1221 		if ((callback = info.kernel) != NULL) {
1222 			if (callback->owner)
1223 				port->owner = callback->owner;
1224 			port->private_data = callback->private_data;
1225 			port->private_free = callback->private_free;
1226 			port->callback_all = callback->callback_all;
1227 			port->event_input = callback->event_input;
1228 			port->c_src.open = callback->subscribe;
1229 			port->c_src.close = callback->unsubscribe;
1230 			port->c_dest.open = callback->use;
1231 			port->c_dest.close = callback->unuse;
1232 		}
1233 	}
1234 
1235 	info.addr = port->addr;
1236 
1237 	snd_seq_set_port_info(port, &info);
1238 	snd_seq_system_client_ev_port_start(port->addr.client, port->addr.port);
1239 
1240 	if (copy_to_user(arg, &info, sizeof(info)))
1241 		return -EFAULT;
1242 
1243 	return 0;
1244 }
1245 
1246 /*
1247  * DELETE PORT ioctl()
1248  */
1249 static int snd_seq_ioctl_delete_port(client_t * client, void __user *arg)
1250 {
1251 	snd_seq_port_info_t info;
1252 	int err;
1253 
1254 	/* set passed parameters */
1255 	if (copy_from_user(&info, arg, sizeof(info)))
1256 		return -EFAULT;
1257 
1258 	/* it is not allowed to remove the port for an another client */
1259 	if (info.addr.client != client->number)
1260 		return -EPERM;
1261 
1262 	err = snd_seq_delete_port(client, info.addr.port);
1263 	if (err >= 0)
1264 		snd_seq_system_client_ev_port_exit(client->number, info.addr.port);
1265 	return err;
1266 }
1267 
1268 
1269 /*
1270  * GET_PORT_INFO ioctl() (on any client)
1271  */
1272 static int snd_seq_ioctl_get_port_info(client_t *client, void __user *arg)
1273 {
1274 	client_t *cptr;
1275 	client_port_t *port;
1276 	snd_seq_port_info_t info;
1277 
1278 	if (copy_from_user(&info, arg, sizeof(info)))
1279 		return -EFAULT;
1280 	cptr = snd_seq_client_use_ptr(info.addr.client);
1281 	if (cptr == NULL)
1282 		return -ENXIO;
1283 
1284 	port = snd_seq_port_use_ptr(cptr, info.addr.port);
1285 	if (port == NULL) {
1286 		snd_seq_client_unlock(cptr);
1287 		return -ENOENT;			/* don't change */
1288 	}
1289 
1290 	/* get port info */
1291 	snd_seq_get_port_info(port, &info);
1292 	snd_seq_port_unlock(port);
1293 	snd_seq_client_unlock(cptr);
1294 
1295 	if (copy_to_user(arg, &info, sizeof(info)))
1296 		return -EFAULT;
1297 	return 0;
1298 }
1299 
1300 
1301 /*
1302  * SET_PORT_INFO ioctl() (only ports on this/own client)
1303  */
1304 static int snd_seq_ioctl_set_port_info(client_t * client, void __user *arg)
1305 {
1306 	client_port_t *port;
1307 	snd_seq_port_info_t info;
1308 
1309 	if (copy_from_user(&info, arg, sizeof(info)))
1310 		return -EFAULT;
1311 
1312 	if (info.addr.client != client->number) /* only set our own ports ! */
1313 		return -EPERM;
1314 	port = snd_seq_port_use_ptr(client, info.addr.port);
1315 	if (port) {
1316 		snd_seq_set_port_info(port, &info);
1317 		snd_seq_port_unlock(port);
1318 	}
1319 	return 0;
1320 }
1321 
1322 
1323 /*
1324  * port subscription (connection)
1325  */
1326 #define PERM_RD		(SNDRV_SEQ_PORT_CAP_READ|SNDRV_SEQ_PORT_CAP_SUBS_READ)
1327 #define PERM_WR		(SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_SUBS_WRITE)
1328 
1329 static int check_subscription_permission(client_t *client, client_port_t *sport,
1330 					 client_port_t *dport,
1331 					 snd_seq_port_subscribe_t *subs)
1332 {
1333 	if (client->number != subs->sender.client &&
1334 	    client->number != subs->dest.client) {
1335 		/* connection by third client - check export permission */
1336 		if (check_port_perm(sport, SNDRV_SEQ_PORT_CAP_NO_EXPORT))
1337 			return -EPERM;
1338 		if (check_port_perm(dport, SNDRV_SEQ_PORT_CAP_NO_EXPORT))
1339 			return -EPERM;
1340 	}
1341 
1342 	/* check read permission */
1343 	/* if sender or receiver is the subscribing client itself,
1344 	 * no permission check is necessary
1345 	 */
1346 	if (client->number != subs->sender.client) {
1347 		if (! check_port_perm(sport, PERM_RD))
1348 			return -EPERM;
1349 	}
1350 	/* check write permission */
1351 	if (client->number != subs->dest.client) {
1352 		if (! check_port_perm(dport, PERM_WR))
1353 			return -EPERM;
1354 	}
1355 	return 0;
1356 }
1357 
1358 /*
1359  * send an subscription notify event to user client:
1360  * client must be user client.
1361  */
1362 int snd_seq_client_notify_subscription(int client, int port,
1363 				       snd_seq_port_subscribe_t *info, int evtype)
1364 {
1365 	snd_seq_event_t event;
1366 
1367 	memset(&event, 0, sizeof(event));
1368 	event.type = evtype;
1369 	event.data.connect.dest = info->dest;
1370 	event.data.connect.sender = info->sender;
1371 
1372 	return snd_seq_system_notify(client, port, &event);  /* non-atomic */
1373 }
1374 
1375 
1376 /*
1377  * add to port's subscription list IOCTL interface
1378  */
1379 static int snd_seq_ioctl_subscribe_port(client_t * client, void __user *arg)
1380 {
1381 	int result = -EINVAL;
1382 	client_t *receiver = NULL, *sender = NULL;
1383 	client_port_t *sport = NULL, *dport = NULL;
1384 	snd_seq_port_subscribe_t subs;
1385 
1386 	if (copy_from_user(&subs, arg, sizeof(subs)))
1387 		return -EFAULT;
1388 
1389 	if ((receiver = snd_seq_client_use_ptr(subs.dest.client)) == NULL)
1390 		goto __end;
1391 	if ((sender = snd_seq_client_use_ptr(subs.sender.client)) == NULL)
1392 		goto __end;
1393 	if ((sport = snd_seq_port_use_ptr(sender, subs.sender.port)) == NULL)
1394 		goto __end;
1395 	if ((dport = snd_seq_port_use_ptr(receiver, subs.dest.port)) == NULL)
1396 		goto __end;
1397 
1398 	result = check_subscription_permission(client, sport, dport, &subs);
1399 	if (result < 0)
1400 		goto __end;
1401 
1402 	/* connect them */
1403 	result = snd_seq_port_connect(client, sender, sport, receiver, dport, &subs);
1404 	if (! result) /* broadcast announce */
1405 		snd_seq_client_notify_subscription(SNDRV_SEQ_ADDRESS_SUBSCRIBERS, 0,
1406 						   &subs, SNDRV_SEQ_EVENT_PORT_SUBSCRIBED);
1407       __end:
1408       	if (sport)
1409 		snd_seq_port_unlock(sport);
1410 	if (dport)
1411 		snd_seq_port_unlock(dport);
1412 	if (sender)
1413 		snd_seq_client_unlock(sender);
1414 	if (receiver)
1415 		snd_seq_client_unlock(receiver);
1416 	return result;
1417 }
1418 
1419 
1420 /*
1421  * remove from port's subscription list
1422  */
1423 static int snd_seq_ioctl_unsubscribe_port(client_t * client, void __user *arg)
1424 {
1425 	int result = -ENXIO;
1426 	client_t *receiver = NULL, *sender = NULL;
1427 	client_port_t *sport = NULL, *dport = NULL;
1428 	snd_seq_port_subscribe_t subs;
1429 
1430 	if (copy_from_user(&subs, arg, sizeof(subs)))
1431 		return -EFAULT;
1432 
1433 	if ((receiver = snd_seq_client_use_ptr(subs.dest.client)) == NULL)
1434 		goto __end;
1435 	if ((sender = snd_seq_client_use_ptr(subs.sender.client)) == NULL)
1436 		goto __end;
1437 	if ((sport = snd_seq_port_use_ptr(sender, subs.sender.port)) == NULL)
1438 		goto __end;
1439 	if ((dport = snd_seq_port_use_ptr(receiver, subs.dest.port)) == NULL)
1440 		goto __end;
1441 
1442 	result = check_subscription_permission(client, sport, dport, &subs);
1443 	if (result < 0)
1444 		goto __end;
1445 
1446 	result = snd_seq_port_disconnect(client, sender, sport, receiver, dport, &subs);
1447 	if (! result) /* broadcast announce */
1448 		snd_seq_client_notify_subscription(SNDRV_SEQ_ADDRESS_SUBSCRIBERS, 0,
1449 						   &subs, SNDRV_SEQ_EVENT_PORT_UNSUBSCRIBED);
1450       __end:
1451       	if (sport)
1452 		snd_seq_port_unlock(sport);
1453 	if (dport)
1454 		snd_seq_port_unlock(dport);
1455 	if (sender)
1456 		snd_seq_client_unlock(sender);
1457 	if (receiver)
1458 		snd_seq_client_unlock(receiver);
1459 	return result;
1460 }
1461 
1462 
1463 /* CREATE_QUEUE ioctl() */
1464 static int snd_seq_ioctl_create_queue(client_t *client, void __user *arg)
1465 {
1466 	snd_seq_queue_info_t info;
1467 	int result;
1468 	queue_t *q;
1469 
1470 	if (copy_from_user(&info, arg, sizeof(info)))
1471 		return -EFAULT;
1472 
1473 	result = snd_seq_queue_alloc(client->number, info.locked, info.flags);
1474 	if (result < 0)
1475 		return result;
1476 
1477 	q = queueptr(result);
1478 	if (q == NULL)
1479 		return -EINVAL;
1480 
1481 	info.queue = q->queue;
1482 	info.locked = q->locked;
1483 	info.owner = q->owner;
1484 
1485 	/* set queue name */
1486 	if (! info.name[0])
1487 		snprintf(info.name, sizeof(info.name), "Queue-%d", q->queue);
1488 	strlcpy(q->name, info.name, sizeof(q->name));
1489 	queuefree(q);
1490 
1491 	if (copy_to_user(arg, &info, sizeof(info)))
1492 		return -EFAULT;
1493 
1494 	return 0;
1495 }
1496 
1497 /* DELETE_QUEUE ioctl() */
1498 static int snd_seq_ioctl_delete_queue(client_t *client, void __user *arg)
1499 {
1500 	snd_seq_queue_info_t info;
1501 
1502 	if (copy_from_user(&info, arg, sizeof(info)))
1503 		return -EFAULT;
1504 
1505 	return snd_seq_queue_delete(client->number, info.queue);
1506 }
1507 
1508 /* GET_QUEUE_INFO ioctl() */
1509 static int snd_seq_ioctl_get_queue_info(client_t *client, void __user *arg)
1510 {
1511 	snd_seq_queue_info_t info;
1512 	queue_t *q;
1513 
1514 	if (copy_from_user(&info, arg, sizeof(info)))
1515 		return -EFAULT;
1516 
1517 	q = queueptr(info.queue);
1518 	if (q == NULL)
1519 		return -EINVAL;
1520 
1521 	memset(&info, 0, sizeof(info));
1522 	info.queue = q->queue;
1523 	info.owner = q->owner;
1524 	info.locked = q->locked;
1525 	strlcpy(info.name, q->name, sizeof(info.name));
1526 	queuefree(q);
1527 
1528 	if (copy_to_user(arg, &info, sizeof(info)))
1529 		return -EFAULT;
1530 
1531 	return 0;
1532 }
1533 
1534 /* SET_QUEUE_INFO ioctl() */
1535 static int snd_seq_ioctl_set_queue_info(client_t *client, void __user *arg)
1536 {
1537 	snd_seq_queue_info_t info;
1538 	queue_t *q;
1539 
1540 	if (copy_from_user(&info, arg, sizeof(info)))
1541 		return -EFAULT;
1542 
1543 	if (info.owner != client->number)
1544 		return -EINVAL;
1545 
1546 	/* change owner/locked permission */
1547 	if (snd_seq_queue_check_access(info.queue, client->number)) {
1548 		if (snd_seq_queue_set_owner(info.queue, client->number, info.locked) < 0)
1549 			return -EPERM;
1550 		if (info.locked)
1551 			snd_seq_queue_use(info.queue, client->number, 1);
1552 	} else {
1553 		return -EPERM;
1554 	}
1555 
1556 	q = queueptr(info.queue);
1557 	if (! q)
1558 		return -EINVAL;
1559 	if (q->owner != client->number) {
1560 		queuefree(q);
1561 		return -EPERM;
1562 	}
1563 	strlcpy(q->name, info.name, sizeof(q->name));
1564 	queuefree(q);
1565 
1566 	return 0;
1567 }
1568 
1569 /* GET_NAMED_QUEUE ioctl() */
1570 static int snd_seq_ioctl_get_named_queue(client_t *client, void __user *arg)
1571 {
1572 	snd_seq_queue_info_t info;
1573 	queue_t *q;
1574 
1575 	if (copy_from_user(&info, arg, sizeof(info)))
1576 		return -EFAULT;
1577 
1578 	q = snd_seq_queue_find_name(info.name);
1579 	if (q == NULL)
1580 		return -EINVAL;
1581 	info.queue = q->queue;
1582 	info.owner = q->owner;
1583 	info.locked = q->locked;
1584 	queuefree(q);
1585 
1586 	if (copy_to_user(arg, &info, sizeof(info)))
1587 		return -EFAULT;
1588 
1589 	return 0;
1590 }
1591 
1592 /* GET_QUEUE_STATUS ioctl() */
1593 static int snd_seq_ioctl_get_queue_status(client_t * client, void __user *arg)
1594 {
1595 	snd_seq_queue_status_t status;
1596 	queue_t *queue;
1597 	seq_timer_t *tmr;
1598 
1599 	if (copy_from_user(&status, arg, sizeof(status)))
1600 		return -EFAULT;
1601 
1602 	queue = queueptr(status.queue);
1603 	if (queue == NULL)
1604 		return -EINVAL;
1605 	memset(&status, 0, sizeof(status));
1606 	status.queue = queue->queue;
1607 
1608 	tmr = queue->timer;
1609 	status.events = queue->tickq->cells + queue->timeq->cells;
1610 
1611 	status.time = snd_seq_timer_get_cur_time(tmr);
1612 	status.tick = snd_seq_timer_get_cur_tick(tmr);
1613 
1614 	status.running = tmr->running;
1615 
1616 	status.flags = queue->flags;
1617 	queuefree(queue);
1618 
1619 	if (copy_to_user(arg, &status, sizeof(status)))
1620 		return -EFAULT;
1621 	return 0;
1622 }
1623 
1624 
1625 /* GET_QUEUE_TEMPO ioctl() */
1626 static int snd_seq_ioctl_get_queue_tempo(client_t * client, void __user *arg)
1627 {
1628 	snd_seq_queue_tempo_t tempo;
1629 	queue_t *queue;
1630 	seq_timer_t *tmr;
1631 
1632 	if (copy_from_user(&tempo, arg, sizeof(tempo)))
1633 		return -EFAULT;
1634 
1635 	queue = queueptr(tempo.queue);
1636 	if (queue == NULL)
1637 		return -EINVAL;
1638 	memset(&tempo, 0, sizeof(tempo));
1639 	tempo.queue = queue->queue;
1640 
1641 	tmr = queue->timer;
1642 
1643 	tempo.tempo = tmr->tempo;
1644 	tempo.ppq = tmr->ppq;
1645 	tempo.skew_value = tmr->skew;
1646 	tempo.skew_base = tmr->skew_base;
1647 	queuefree(queue);
1648 
1649 	if (copy_to_user(arg, &tempo, sizeof(tempo)))
1650 		return -EFAULT;
1651 	return 0;
1652 }
1653 
1654 
1655 /* SET_QUEUE_TEMPO ioctl() */
1656 int snd_seq_set_queue_tempo(int client, snd_seq_queue_tempo_t *tempo)
1657 {
1658 	if (!snd_seq_queue_check_access(tempo->queue, client))
1659 		return -EPERM;
1660 	return snd_seq_queue_timer_set_tempo(tempo->queue, client, tempo);
1661 }
1662 
1663 static int snd_seq_ioctl_set_queue_tempo(client_t * client, void __user *arg)
1664 {
1665 	int result;
1666 	snd_seq_queue_tempo_t tempo;
1667 
1668 	if (copy_from_user(&tempo, arg, sizeof(tempo)))
1669 		return -EFAULT;
1670 
1671 	result = snd_seq_set_queue_tempo(client->number, &tempo);
1672 	return result < 0 ? result : 0;
1673 }
1674 
1675 
1676 /* GET_QUEUE_TIMER ioctl() */
1677 static int snd_seq_ioctl_get_queue_timer(client_t * client, void __user *arg)
1678 {
1679 	snd_seq_queue_timer_t timer;
1680 	queue_t *queue;
1681 	seq_timer_t *tmr;
1682 
1683 	if (copy_from_user(&timer, arg, sizeof(timer)))
1684 		return -EFAULT;
1685 
1686 	queue = queueptr(timer.queue);
1687 	if (queue == NULL)
1688 		return -EINVAL;
1689 
1690 	if (down_interruptible(&queue->timer_mutex)) {
1691 		queuefree(queue);
1692 		return -ERESTARTSYS;
1693 	}
1694 	tmr = queue->timer;
1695 	memset(&timer, 0, sizeof(timer));
1696 	timer.queue = queue->queue;
1697 
1698 	timer.type = tmr->type;
1699 	if (tmr->type == SNDRV_SEQ_TIMER_ALSA) {
1700 		timer.u.alsa.id = tmr->alsa_id;
1701 		timer.u.alsa.resolution = tmr->preferred_resolution;
1702 	}
1703 	up(&queue->timer_mutex);
1704 	queuefree(queue);
1705 
1706 	if (copy_to_user(arg, &timer, sizeof(timer)))
1707 		return -EFAULT;
1708 	return 0;
1709 }
1710 
1711 
1712 /* SET_QUEUE_TIMER ioctl() */
1713 static int snd_seq_ioctl_set_queue_timer(client_t * client, void __user *arg)
1714 {
1715 	int result = 0;
1716 	snd_seq_queue_timer_t timer;
1717 
1718 	if (copy_from_user(&timer, arg, sizeof(timer)))
1719 		return -EFAULT;
1720 
1721 	if (timer.type != SNDRV_SEQ_TIMER_ALSA)
1722 		return -EINVAL;
1723 
1724 	if (snd_seq_queue_check_access(timer.queue, client->number)) {
1725 		queue_t *q;
1726 		seq_timer_t *tmr;
1727 
1728 		q = queueptr(timer.queue);
1729 		if (q == NULL)
1730 			return -ENXIO;
1731 		if (down_interruptible(&q->timer_mutex)) {
1732 			queuefree(q);
1733 			return -ERESTARTSYS;
1734 		}
1735 		tmr = q->timer;
1736 		snd_seq_queue_timer_close(timer.queue);
1737 		tmr->type = timer.type;
1738 		if (tmr->type == SNDRV_SEQ_TIMER_ALSA) {
1739 			tmr->alsa_id = timer.u.alsa.id;
1740 			tmr->preferred_resolution = timer.u.alsa.resolution;
1741 		}
1742 		result = snd_seq_queue_timer_open(timer.queue);
1743 		up(&q->timer_mutex);
1744 		queuefree(q);
1745 	} else {
1746 		return -EPERM;
1747 	}
1748 
1749 	return result;
1750 }
1751 
1752 
1753 /* GET_QUEUE_CLIENT ioctl() */
1754 static int snd_seq_ioctl_get_queue_client(client_t * client, void __user *arg)
1755 {
1756 	snd_seq_queue_client_t info;
1757 	int used;
1758 
1759 	if (copy_from_user(&info, arg, sizeof(info)))
1760 		return -EFAULT;
1761 
1762 	used = snd_seq_queue_is_used(info.queue, client->number);
1763 	if (used < 0)
1764 		return -EINVAL;
1765 	info.used = used;
1766 	info.client = client->number;
1767 
1768 	if (copy_to_user(arg, &info, sizeof(info)))
1769 		return -EFAULT;
1770 	return 0;
1771 }
1772 
1773 
1774 /* SET_QUEUE_CLIENT ioctl() */
1775 static int snd_seq_ioctl_set_queue_client(client_t * client, void __user *arg)
1776 {
1777 	int err;
1778 	snd_seq_queue_client_t info;
1779 
1780 	if (copy_from_user(&info, arg, sizeof(info)))
1781 		return -EFAULT;
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(client_t * client, void __user *arg)
1795 {
1796 	snd_seq_client_pool_t info;
1797 	client_t *cptr;
1798 
1799 	if (copy_from_user(&info, arg, sizeof(info)))
1800 		return -EFAULT;
1801 
1802 	cptr = snd_seq_client_use_ptr(info.client);
1803 	if (cptr == NULL)
1804 		return -ENOENT;
1805 	memset(&info, 0, sizeof(info));
1806 	info.output_pool = cptr->pool->size;
1807 	info.output_room = cptr->pool->room;
1808 	info.output_free = info.output_pool;
1809 	if (cptr->pool)
1810 		info.output_free = snd_seq_unused_cells(cptr->pool);
1811 	if (cptr->type == USER_CLIENT) {
1812 		info.input_pool = cptr->data.user.fifo_pool_size;
1813 		info.input_free = info.input_pool;
1814 		if (cptr->data.user.fifo)
1815 			info.input_free = snd_seq_unused_cells(cptr->data.user.fifo->pool);
1816 	} else {
1817 		info.input_pool = 0;
1818 		info.input_free = 0;
1819 	}
1820 	snd_seq_client_unlock(cptr);
1821 
1822 	if (copy_to_user(arg, &info, sizeof(info)))
1823 		return -EFAULT;
1824 	return 0;
1825 }
1826 
1827 /* SET_CLIENT_POOL ioctl() */
1828 static int snd_seq_ioctl_set_client_pool(client_t * client, void __user *arg)
1829 {
1830 	snd_seq_client_pool_t info;
1831 	int rc;
1832 
1833 	if (copy_from_user(&info, arg, sizeof(info)))
1834 		return -EFAULT;
1835 
1836 	if (client->number != info.client)
1837 		return -EINVAL; /* can't change other clients */
1838 
1839 	if (info.output_pool >= 1 && info.output_pool <= SNDRV_SEQ_MAX_EVENTS &&
1840 	    (! snd_seq_write_pool_allocated(client) ||
1841 	     info.output_pool != client->pool->size)) {
1842 		if (snd_seq_write_pool_allocated(client)) {
1843 			/* remove all existing cells */
1844 			snd_seq_queue_client_leave_cells(client->number);
1845 			snd_seq_pool_done(client->pool);
1846 		}
1847 		client->pool->size = info.output_pool;
1848 		rc = snd_seq_pool_init(client->pool);
1849 		if (rc < 0)
1850 			return rc;
1851 	}
1852 	if (client->type == USER_CLIENT && client->data.user.fifo != NULL &&
1853 	    info.input_pool >= 1 &&
1854 	    info.input_pool <= SNDRV_SEQ_MAX_CLIENT_EVENTS &&
1855 	    info.input_pool != client->data.user.fifo_pool_size) {
1856 		/* change pool size */
1857 		rc = snd_seq_fifo_resize(client->data.user.fifo, info.input_pool);
1858 		if (rc < 0)
1859 			return rc;
1860 		client->data.user.fifo_pool_size = info.input_pool;
1861 	}
1862 	if (info.output_room >= 1 &&
1863 	    info.output_room <= client->pool->size) {
1864 		client->pool->room  = info.output_room;
1865 	}
1866 
1867 	return snd_seq_ioctl_get_client_pool(client, arg);
1868 }
1869 
1870 
1871 /* REMOVE_EVENTS ioctl() */
1872 static int snd_seq_ioctl_remove_events(client_t * client, void __user *arg)
1873 {
1874 	snd_seq_remove_events_t info;
1875 
1876 	if (copy_from_user(&info, arg, sizeof(info)))
1877 		return -EFAULT;
1878 
1879 	/*
1880 	 * Input mostly not implemented XXX.
1881 	 */
1882 	if (info.remove_mode & SNDRV_SEQ_REMOVE_INPUT) {
1883 		/*
1884 		 * No restrictions so for a user client we can clear
1885 		 * the whole fifo
1886 		 */
1887 		if (client->type == USER_CLIENT)
1888 			snd_seq_fifo_clear(client->data.user.fifo);
1889 	}
1890 
1891 	if (info.remove_mode & SNDRV_SEQ_REMOVE_OUTPUT)
1892 		snd_seq_queue_remove_cells(client->number, &info);
1893 
1894 	return 0;
1895 }
1896 
1897 
1898 /*
1899  * get subscription info
1900  */
1901 static int snd_seq_ioctl_get_subscription(client_t *client, void __user *arg)
1902 {
1903 	int result;
1904 	client_t *sender = NULL;
1905 	client_port_t *sport = NULL;
1906 	snd_seq_port_subscribe_t subs;
1907 	subscribers_t *p;
1908 
1909 	if (copy_from_user(&subs, arg, sizeof(subs)))
1910 		return -EFAULT;
1911 
1912 	result = -EINVAL;
1913 	if ((sender = snd_seq_client_use_ptr(subs.sender.client)) == NULL)
1914 		goto __end;
1915 	if ((sport = snd_seq_port_use_ptr(sender, subs.sender.port)) == NULL)
1916 		goto __end;
1917 	p = snd_seq_port_get_subscription(&sport->c_src, &subs.dest);
1918 	if (p) {
1919 		result = 0;
1920 		subs = p->info;
1921 	} else
1922 		result = -ENOENT;
1923 
1924       __end:
1925       	if (sport)
1926 		snd_seq_port_unlock(sport);
1927 	if (sender)
1928 		snd_seq_client_unlock(sender);
1929 	if (result >= 0) {
1930 		if (copy_to_user(arg, &subs, sizeof(subs)))
1931 			return -EFAULT;
1932 	}
1933 	return result;
1934 }
1935 
1936 
1937 /*
1938  * get subscription info - check only its presence
1939  */
1940 static int snd_seq_ioctl_query_subs(client_t *client, void __user *arg)
1941 {
1942 	int result = -ENXIO;
1943 	client_t *cptr = NULL;
1944 	client_port_t *port = NULL;
1945 	snd_seq_query_subs_t subs;
1946 	port_subs_info_t *group;
1947 	struct list_head *p;
1948 	int i;
1949 
1950 	if (copy_from_user(&subs, arg, sizeof(subs)))
1951 		return -EFAULT;
1952 
1953 	if ((cptr = snd_seq_client_use_ptr(subs.root.client)) == NULL)
1954 		goto __end;
1955 	if ((port = snd_seq_port_use_ptr(cptr, subs.root.port)) == NULL)
1956 		goto __end;
1957 
1958 	switch (subs.type) {
1959 	case SNDRV_SEQ_QUERY_SUBS_READ:
1960 		group = &port->c_src;
1961 		break;
1962 	case SNDRV_SEQ_QUERY_SUBS_WRITE:
1963 		group = &port->c_dest;
1964 		break;
1965 	default:
1966 		goto __end;
1967 	}
1968 
1969 	down_read(&group->list_mutex);
1970 	/* search for the subscriber */
1971 	subs.num_subs = group->count;
1972 	i = 0;
1973 	result = -ENOENT;
1974 	list_for_each(p, &group->list_head) {
1975 		if (i++ == subs.index) {
1976 			/* found! */
1977 			subscribers_t *s;
1978 			if (subs.type == SNDRV_SEQ_QUERY_SUBS_READ) {
1979 				s = list_entry(p, subscribers_t, src_list);
1980 				subs.addr = s->info.dest;
1981 			} else {
1982 				s = list_entry(p, subscribers_t, dest_list);
1983 				subs.addr = s->info.sender;
1984 			}
1985 			subs.flags = s->info.flags;
1986 			subs.queue = s->info.queue;
1987 			result = 0;
1988 			break;
1989 		}
1990 	}
1991 	up_read(&group->list_mutex);
1992 
1993       __end:
1994    	if (port)
1995 		snd_seq_port_unlock(port);
1996 	if (cptr)
1997 		snd_seq_client_unlock(cptr);
1998 	if (result >= 0) {
1999 		if (copy_to_user(arg, &subs, sizeof(subs)))
2000 			return -EFAULT;
2001 	}
2002 	return result;
2003 }
2004 
2005 
2006 /*
2007  * query next client
2008  */
2009 static int snd_seq_ioctl_query_next_client(client_t *client, void __user *arg)
2010 {
2011 	client_t *cptr = NULL;
2012 	snd_seq_client_info_t info;
2013 
2014 	if (copy_from_user(&info, arg, sizeof(info)))
2015 		return -EFAULT;
2016 
2017 	/* search for next client */
2018 	info.client++;
2019 	if (info.client < 0)
2020 		info.client = 0;
2021 	for (; info.client < SNDRV_SEQ_MAX_CLIENTS; info.client++) {
2022 		cptr = snd_seq_client_use_ptr(info.client);
2023 		if (cptr)
2024 			break; /* found */
2025 	}
2026 	if (cptr == NULL)
2027 		return -ENOENT;
2028 
2029 	get_client_info(cptr, &info);
2030 	snd_seq_client_unlock(cptr);
2031 
2032 	if (copy_to_user(arg, &info, sizeof(info)))
2033 		return -EFAULT;
2034 	return 0;
2035 }
2036 
2037 /*
2038  * query next port
2039  */
2040 static int snd_seq_ioctl_query_next_port(client_t *client, void __user *arg)
2041 {
2042 	client_t *cptr;
2043 	client_port_t *port = NULL;
2044 	snd_seq_port_info_t info;
2045 
2046 	if (copy_from_user(&info, arg, sizeof(info)))
2047 		return -EFAULT;
2048 	cptr = snd_seq_client_use_ptr(info.addr.client);
2049 	if (cptr == NULL)
2050 		return -ENXIO;
2051 
2052 	/* search for next port */
2053 	info.addr.port++;
2054 	port = snd_seq_port_query_nearest(cptr, &info);
2055 	if (port == NULL) {
2056 		snd_seq_client_unlock(cptr);
2057 		return -ENOENT;
2058 	}
2059 
2060 	/* get port info */
2061 	info.addr = port->addr;
2062 	snd_seq_get_port_info(port, &info);
2063 	snd_seq_port_unlock(port);
2064 	snd_seq_client_unlock(cptr);
2065 
2066 	if (copy_to_user(arg, &info, sizeof(info)))
2067 		return -EFAULT;
2068 	return 0;
2069 }
2070 
2071 /* -------------------------------------------------------- */
2072 
2073 static struct seq_ioctl_table {
2074 	unsigned int cmd;
2075 	int (*func)(client_t *client, void __user * arg);
2076 } ioctl_tables[] = {
2077 	{ SNDRV_SEQ_IOCTL_SYSTEM_INFO, snd_seq_ioctl_system_info },
2078 	{ SNDRV_SEQ_IOCTL_RUNNING_MODE, snd_seq_ioctl_running_mode },
2079 	{ SNDRV_SEQ_IOCTL_GET_CLIENT_INFO, snd_seq_ioctl_get_client_info },
2080 	{ SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, snd_seq_ioctl_set_client_info },
2081 	{ SNDRV_SEQ_IOCTL_CREATE_PORT, snd_seq_ioctl_create_port },
2082 	{ SNDRV_SEQ_IOCTL_DELETE_PORT, snd_seq_ioctl_delete_port },
2083 	{ SNDRV_SEQ_IOCTL_GET_PORT_INFO, snd_seq_ioctl_get_port_info },
2084 	{ SNDRV_SEQ_IOCTL_SET_PORT_INFO, snd_seq_ioctl_set_port_info },
2085 	{ SNDRV_SEQ_IOCTL_SUBSCRIBE_PORT, snd_seq_ioctl_subscribe_port },
2086 	{ SNDRV_SEQ_IOCTL_UNSUBSCRIBE_PORT, snd_seq_ioctl_unsubscribe_port },
2087 	{ SNDRV_SEQ_IOCTL_CREATE_QUEUE, snd_seq_ioctl_create_queue },
2088 	{ SNDRV_SEQ_IOCTL_DELETE_QUEUE, snd_seq_ioctl_delete_queue },
2089 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_INFO, snd_seq_ioctl_get_queue_info },
2090 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_INFO, snd_seq_ioctl_set_queue_info },
2091 	{ SNDRV_SEQ_IOCTL_GET_NAMED_QUEUE, snd_seq_ioctl_get_named_queue },
2092 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_STATUS, snd_seq_ioctl_get_queue_status },
2093 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_TEMPO, snd_seq_ioctl_get_queue_tempo },
2094 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_TEMPO, snd_seq_ioctl_set_queue_tempo },
2095 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_TIMER, snd_seq_ioctl_get_queue_timer },
2096 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_TIMER, snd_seq_ioctl_set_queue_timer },
2097 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_CLIENT, snd_seq_ioctl_get_queue_client },
2098 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_CLIENT, snd_seq_ioctl_set_queue_client },
2099 	{ SNDRV_SEQ_IOCTL_GET_CLIENT_POOL, snd_seq_ioctl_get_client_pool },
2100 	{ SNDRV_SEQ_IOCTL_SET_CLIENT_POOL, snd_seq_ioctl_set_client_pool },
2101 	{ SNDRV_SEQ_IOCTL_GET_SUBSCRIPTION, snd_seq_ioctl_get_subscription },
2102 	{ SNDRV_SEQ_IOCTL_QUERY_NEXT_CLIENT, snd_seq_ioctl_query_next_client },
2103 	{ SNDRV_SEQ_IOCTL_QUERY_NEXT_PORT, snd_seq_ioctl_query_next_port },
2104 	{ SNDRV_SEQ_IOCTL_REMOVE_EVENTS, snd_seq_ioctl_remove_events },
2105 	{ SNDRV_SEQ_IOCTL_QUERY_SUBS, snd_seq_ioctl_query_subs },
2106 	{ 0, NULL },
2107 };
2108 
2109 static int snd_seq_do_ioctl(client_t *client, unsigned int cmd, void __user *arg)
2110 {
2111 	struct seq_ioctl_table *p;
2112 
2113 	switch (cmd) {
2114 	case SNDRV_SEQ_IOCTL_PVERSION:
2115 		/* return sequencer version number */
2116 		return put_user(SNDRV_SEQ_VERSION, (int __user *)arg) ? -EFAULT : 0;
2117 	case SNDRV_SEQ_IOCTL_CLIENT_ID:
2118 		/* return the id of this client */
2119 		return put_user(client->number, (int __user *)arg) ? -EFAULT : 0;
2120 	}
2121 
2122 	if (! arg)
2123 		return -EFAULT;
2124 	for (p = ioctl_tables; p->cmd; p++) {
2125 		if (p->cmd == cmd)
2126 			return p->func(client, arg);
2127 	}
2128 	snd_printd("seq unknown ioctl() 0x%x (type='%c', number=0x%2x)\n",
2129 		   cmd, _IOC_TYPE(cmd), _IOC_NR(cmd));
2130 	return -ENOTTY;
2131 }
2132 
2133 
2134 static long snd_seq_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2135 {
2136 	client_t *client = (client_t *) file->private_data;
2137 
2138 	snd_assert(client != NULL, return -ENXIO);
2139 
2140 	return snd_seq_do_ioctl(client, cmd, (void __user *) arg);
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(snd_card_t *card, int client_index, snd_seq_client_callback_t * callback)
2154 {
2155 	client_t *client;
2156 
2157 	snd_assert(! in_interrupt(), return -EBUSY);
2158 
2159 	if (callback == NULL)
2160 		return -EINVAL;
2161 	if (card && client_index > 7)
2162 		return -EINVAL;
2163 	if (card == NULL && client_index > 63)
2164 		return -EINVAL;
2165 	if (card)
2166 		client_index += 64 + (card->number << 3);
2167 
2168 	if (down_interruptible(&register_mutex))
2169 		return -ERESTARTSYS;
2170 	/* empty write queue as default */
2171 	client = seq_create_client1(client_index, 0);
2172 	if (client == NULL) {
2173 		up(&register_mutex);
2174 		return -EBUSY;	/* failure code */
2175 	}
2176 	usage_alloc(&client_usage, 1);
2177 
2178 	client->accept_input = callback->allow_output;
2179 	client->accept_output = callback->allow_input;
2180 
2181 	/* fill client data */
2182 	client->data.kernel.card = card;
2183 	client->data.kernel.private_data = callback->private_data;
2184 	sprintf(client->name, "Client-%d", client->number);
2185 
2186 	client->type = KERNEL_CLIENT;
2187 	up(&register_mutex);
2188 
2189 	/* make others aware this new client */
2190 	snd_seq_system_client_ev_client_start(client->number);
2191 
2192 	/* return client number to caller */
2193 	return client->number;
2194 }
2195 
2196 /* exported to kernel modules */
2197 int snd_seq_delete_kernel_client(int client)
2198 {
2199 	client_t *ptr;
2200 
2201 	snd_assert(! in_interrupt(), return -EBUSY);
2202 
2203 	ptr = clientptr(client);
2204 	if (ptr == NULL)
2205 		return -EINVAL;
2206 
2207 	seq_free_client(ptr);
2208 	kfree(ptr);
2209 	return 0;
2210 }
2211 
2212 
2213 /* skeleton to enqueue event, called from snd_seq_kernel_client_enqueue
2214  * and snd_seq_kernel_client_enqueue_blocking
2215  */
2216 static int kernel_client_enqueue(int client, snd_seq_event_t *ev,
2217 				 struct file *file, int blocking,
2218 				 int atomic, int hop)
2219 {
2220 	client_t *cptr;
2221 	int result;
2222 
2223 	snd_assert(ev != NULL, return -EINVAL);
2224 
2225 	if (ev->type == SNDRV_SEQ_EVENT_NONE)
2226 		return 0; /* ignore this */
2227 	if (ev->type == SNDRV_SEQ_EVENT_KERNEL_ERROR)
2228 		return -EINVAL; /* quoted events can't be enqueued */
2229 
2230 	/* fill in client number */
2231 	ev->source.client = client;
2232 
2233 	if (check_event_type_and_length(ev))
2234 		return -EINVAL;
2235 
2236 	cptr = snd_seq_client_use_ptr(client);
2237 	if (cptr == NULL)
2238 		return -EINVAL;
2239 
2240 	if (! cptr->accept_output)
2241 		result = -EPERM;
2242 	else /* send it */
2243 		result = snd_seq_client_enqueue_event(cptr, ev, file, blocking, atomic, hop);
2244 
2245 	snd_seq_client_unlock(cptr);
2246 	return result;
2247 }
2248 
2249 /*
2250  * exported, called by kernel clients to enqueue events (w/o blocking)
2251  *
2252  * RETURN VALUE: zero if succeed, negative if error
2253  */
2254 int snd_seq_kernel_client_enqueue(int client, snd_seq_event_t * ev,
2255 				  int atomic, int hop)
2256 {
2257 	return kernel_client_enqueue(client, ev, NULL, 0, atomic, hop);
2258 }
2259 
2260 /*
2261  * exported, called by kernel clients to enqueue events (with blocking)
2262  *
2263  * RETURN VALUE: zero if succeed, negative if error
2264  */
2265 int snd_seq_kernel_client_enqueue_blocking(int client, snd_seq_event_t * ev,
2266 					   struct file *file,
2267 					   int atomic, int hop)
2268 {
2269 	return kernel_client_enqueue(client, ev, file, 1, atomic, hop);
2270 }
2271 
2272 
2273 /*
2274  * exported, called by kernel clients to dispatch events directly to other
2275  * clients, bypassing the queues.  Event time-stamp will be updated.
2276  *
2277  * RETURN VALUE: negative = delivery failed,
2278  *		 zero, or positive: the number of delivered events
2279  */
2280 int snd_seq_kernel_client_dispatch(int client, snd_seq_event_t * ev,
2281 				   int atomic, int hop)
2282 {
2283 	client_t *cptr;
2284 	int result;
2285 
2286 	snd_assert(ev != NULL, return -EINVAL);
2287 
2288 	/* fill in client number */
2289 	ev->queue = SNDRV_SEQ_QUEUE_DIRECT;
2290 	ev->source.client = client;
2291 
2292 	if (check_event_type_and_length(ev))
2293 		return -EINVAL;
2294 
2295 	cptr = snd_seq_client_use_ptr(client);
2296 	if (cptr == NULL)
2297 		return -EINVAL;
2298 
2299 	if (!cptr->accept_output)
2300 		result = -EPERM;
2301 	else
2302 		result = snd_seq_deliver_event(cptr, ev, atomic, hop);
2303 
2304 	snd_seq_client_unlock(cptr);
2305 	return result;
2306 }
2307 
2308 
2309 /*
2310  * exported, called by kernel clients to perform same functions as with
2311  * userland ioctl()
2312  */
2313 int snd_seq_kernel_client_ctl(int clientid, unsigned int cmd, void *arg)
2314 {
2315 	client_t *client;
2316 	mm_segment_t fs;
2317 	int result;
2318 
2319 	client = clientptr(clientid);
2320 	if (client == NULL)
2321 		return -ENXIO;
2322 	fs = snd_enter_user();
2323 	result = snd_seq_do_ioctl(client, cmd, (void __user *)arg);
2324 	snd_leave_user(fs);
2325 	return result;
2326 }
2327 
2328 
2329 /* exported (for OSS emulator) */
2330 int snd_seq_kernel_client_write_poll(int clientid, struct file *file, poll_table *wait)
2331 {
2332 	client_t *client;
2333 
2334 	client = clientptr(clientid);
2335 	if (client == NULL)
2336 		return -ENXIO;
2337 
2338 	if (! snd_seq_write_pool_allocated(client))
2339 		return 1;
2340 	if (snd_seq_pool_poll_wait(client->pool, file, wait))
2341 		return 1;
2342 	return 0;
2343 }
2344 
2345 /*---------------------------------------------------------------------------*/
2346 
2347 /*
2348  *  /proc interface
2349  */
2350 static void snd_seq_info_dump_subscribers(snd_info_buffer_t *buffer, port_subs_info_t *group, int is_src, char *msg)
2351 {
2352 	struct list_head *p;
2353 	subscribers_t *s;
2354 	int count = 0;
2355 
2356 	down_read(&group->list_mutex);
2357 	if (list_empty(&group->list_head)) {
2358 		up_read(&group->list_mutex);
2359 		return;
2360 	}
2361 	snd_iprintf(buffer, msg);
2362 	list_for_each(p, &group->list_head) {
2363 		if (is_src)
2364 			s = list_entry(p, subscribers_t, src_list);
2365 		else
2366 			s = list_entry(p, subscribers_t, dest_list);
2367 		if (count++)
2368 			snd_iprintf(buffer, ", ");
2369 		snd_iprintf(buffer, "%d:%d",
2370 			    is_src ? s->info.dest.client : s->info.sender.client,
2371 			    is_src ? s->info.dest.port : s->info.sender.port);
2372 		if (s->info.flags & SNDRV_SEQ_PORT_SUBS_TIMESTAMP)
2373 			snd_iprintf(buffer, "[%c:%d]", ((s->info.flags & SNDRV_SEQ_PORT_SUBS_TIME_REAL) ? 'r' : 't'), s->info.queue);
2374 		if (group->exclusive)
2375 			snd_iprintf(buffer, "[ex]");
2376 	}
2377 	up_read(&group->list_mutex);
2378 	snd_iprintf(buffer, "\n");
2379 }
2380 
2381 #define FLAG_PERM_RD(perm) ((perm) & SNDRV_SEQ_PORT_CAP_READ ? ((perm) & SNDRV_SEQ_PORT_CAP_SUBS_READ ? 'R' : 'r') : '-')
2382 #define FLAG_PERM_WR(perm) ((perm) & SNDRV_SEQ_PORT_CAP_WRITE ? ((perm) & SNDRV_SEQ_PORT_CAP_SUBS_WRITE ? 'W' : 'w') : '-')
2383 #define FLAG_PERM_EX(perm) ((perm) & SNDRV_SEQ_PORT_CAP_NO_EXPORT ? '-' : 'e')
2384 
2385 #define FLAG_PERM_DUPLEX(perm) ((perm) & SNDRV_SEQ_PORT_CAP_DUPLEX ? 'X' : '-')
2386 
2387 static void snd_seq_info_dump_ports(snd_info_buffer_t *buffer, client_t *client)
2388 {
2389 	struct list_head *l;
2390 
2391 	down(&client->ports_mutex);
2392 	list_for_each(l, &client->ports_list_head) {
2393 		client_port_t *p = list_entry(l, client_port_t, list);
2394 		snd_iprintf(buffer, "  Port %3d : \"%s\" (%c%c%c%c)\n",
2395 			    p->addr.port, p->name,
2396 			    FLAG_PERM_RD(p->capability),
2397 			    FLAG_PERM_WR(p->capability),
2398 			    FLAG_PERM_EX(p->capability),
2399 			    FLAG_PERM_DUPLEX(p->capability));
2400 		snd_seq_info_dump_subscribers(buffer, &p->c_src, 1, "    Connecting To: ");
2401 		snd_seq_info_dump_subscribers(buffer, &p->c_dest, 0, "    Connected From: ");
2402 	}
2403 	up(&client->ports_mutex);
2404 }
2405 
2406 
2407 /* exported to seq_info.c */
2408 void snd_seq_info_clients_read(snd_info_entry_t *entry,
2409 			       snd_info_buffer_t * buffer)
2410 {
2411 	extern void snd_seq_info_pool(snd_info_buffer_t * buffer, pool_t * pool, char *space);
2412 	int c;
2413 	client_t *client;
2414 
2415 	snd_iprintf(buffer, "Client info\n");
2416 	snd_iprintf(buffer, "  cur  clients : %d\n", client_usage.cur);
2417 	snd_iprintf(buffer, "  peak clients : %d\n", client_usage.peak);
2418 	snd_iprintf(buffer, "  max  clients : %d\n", SNDRV_SEQ_MAX_CLIENTS);
2419 	snd_iprintf(buffer, "\n");
2420 
2421 	/* list the client table */
2422 	for (c = 0; c < SNDRV_SEQ_MAX_CLIENTS; c++) {
2423 		client = snd_seq_client_use_ptr(c);
2424 		if (client == NULL)
2425 			continue;
2426 		if (client->type == NO_CLIENT) {
2427 			snd_seq_client_unlock(client);
2428 			continue;
2429 		}
2430 
2431 		snd_iprintf(buffer, "Client %3d : \"%s\" [%s]\n",
2432 			    c, client->name,
2433 			    client->type == USER_CLIENT ? "User" : "Kernel");
2434 		snd_seq_info_dump_ports(buffer, client);
2435 		if (snd_seq_write_pool_allocated(client)) {
2436 			snd_iprintf(buffer, "  Output pool :\n");
2437 			snd_seq_info_pool(buffer, client->pool, "    ");
2438 		}
2439 		if (client->type == USER_CLIENT && client->data.user.fifo &&
2440 		    client->data.user.fifo->pool) {
2441 			snd_iprintf(buffer, "  Input pool :\n");
2442 			snd_seq_info_pool(buffer, client->data.user.fifo->pool, "    ");
2443 		}
2444 		snd_seq_client_unlock(client);
2445 	}
2446 }
2447 
2448 
2449 /*---------------------------------------------------------------------------*/
2450 
2451 
2452 /*
2453  *  REGISTRATION PART
2454  */
2455 
2456 static struct file_operations snd_seq_f_ops =
2457 {
2458 	.owner =	THIS_MODULE,
2459 	.read =		snd_seq_read,
2460 	.write =	snd_seq_write,
2461 	.open =		snd_seq_open,
2462 	.release =	snd_seq_release,
2463 	.poll =		snd_seq_poll,
2464 	.unlocked_ioctl =	snd_seq_ioctl,
2465 	.compat_ioctl =	snd_seq_ioctl_compat,
2466 };
2467 
2468 static snd_minor_t snd_seq_reg =
2469 {
2470 	.comment =	"sequencer",
2471 	.f_ops =	&snd_seq_f_ops,
2472 };
2473 
2474 
2475 /*
2476  * register sequencer device
2477  */
2478 int __init snd_sequencer_device_init(void)
2479 {
2480 	int err;
2481 
2482 	if (down_interruptible(&register_mutex))
2483 		return -ERESTARTSYS;
2484 
2485 	if ((err = snd_register_device(SNDRV_DEVICE_TYPE_SEQUENCER, NULL, 0, &snd_seq_reg, "seq")) < 0) {
2486 		up(&register_mutex);
2487 		return err;
2488 	}
2489 
2490 	up(&register_mutex);
2491 
2492 	return 0;
2493 }
2494 
2495 
2496 
2497 /*
2498  * unregister sequencer device
2499  */
2500 void __exit snd_sequencer_device_done(void)
2501 {
2502 	snd_unregister_device(SNDRV_DEVICE_TYPE_SEQUENCER, NULL, 0);
2503 }
2504