xref: /linux/sound/core/seq/seq_clientmgr.c (revision ff64846bee0e7e3e7bc9363ebad3bab42dd27e24)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  ALSA sequencer Client Manager
4  *  Copyright (c) 1998-2001 by Frank van de Pol <fvdpol@coil.demon.nl>
5  *                             Jaroslav Kysela <perex@perex.cz>
6  *                             Takashi Iwai <tiwai@suse.de>
7  */
8 
9 #include <linux/init.h>
10 #include <linux/export.h>
11 #include <linux/slab.h>
12 #include <sound/core.h>
13 #include <sound/minors.h>
14 #include <linux/kmod.h>
15 
16 #include <sound/seq_kernel.h>
17 #include <sound/ump.h>
18 #include "seq_clientmgr.h"
19 #include "seq_memory.h"
20 #include "seq_queue.h"
21 #include "seq_timer.h"
22 #include "seq_info.h"
23 #include "seq_system.h"
24 #include "seq_ump_convert.h"
25 #include <sound/seq_device.h>
26 #ifdef CONFIG_COMPAT
27 #include <linux/compat.h>
28 #endif
29 
30 /* Client Manager
31 
32  * this module handles the connections of userland and kernel clients
33  *
34  */
35 
36 /*
37  * There are four ranges of client numbers (last two shared):
38  * 0..15: global clients
39  * 16..127: statically allocated client numbers for cards 0..27
40  * 128..191: dynamically allocated client numbers for cards 28..31
41  * 128..191: dynamically allocated client numbers for applications
42  */
43 
44 /* number of kernel non-card clients */
45 #define SNDRV_SEQ_GLOBAL_CLIENTS	16
46 /* clients per cards, for static clients */
47 #define SNDRV_SEQ_CLIENTS_PER_CARD	4
48 /* dynamically allocated client numbers (both kernel drivers and user space) */
49 #define SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN	128
50 
51 #define SNDRV_SEQ_LFLG_INPUT	0x0001
52 #define SNDRV_SEQ_LFLG_OUTPUT	0x0002
53 #define SNDRV_SEQ_LFLG_OPEN	(SNDRV_SEQ_LFLG_INPUT|SNDRV_SEQ_LFLG_OUTPUT)
54 
55 static DEFINE_SPINLOCK(clients_lock);
56 static DEFINE_MUTEX(register_mutex);
57 
58 /*
59  * client table
60  */
61 static char clienttablock[SNDRV_SEQ_MAX_CLIENTS];
62 static struct snd_seq_client *clienttab[SNDRV_SEQ_MAX_CLIENTS];
63 static struct snd_seq_usage client_usage;
64 
65 /*
66  * prototypes
67  */
68 static int bounce_error_event(struct snd_seq_client *client,
69 			      struct snd_seq_event *event,
70 			      int err, int atomic, int hop);
71 static int snd_seq_deliver_single_event(struct snd_seq_client *client,
72 					struct snd_seq_event *event,
73 					int atomic, int hop);
74 
75 #if IS_ENABLED(CONFIG_SND_SEQ_UMP)
76 static void free_ump_info(struct snd_seq_client *client);
77 #endif
78 
79 /*
80  */
81 static inline unsigned short snd_seq_file_flags(struct file *file)
82 {
83         switch (file->f_mode & (FMODE_READ | FMODE_WRITE)) {
84         case FMODE_WRITE:
85                 return SNDRV_SEQ_LFLG_OUTPUT;
86         case FMODE_READ:
87                 return SNDRV_SEQ_LFLG_INPUT;
88         default:
89                 return SNDRV_SEQ_LFLG_OPEN;
90         }
91 }
92 
93 static inline int snd_seq_write_pool_allocated(struct snd_seq_client *client)
94 {
95 	return snd_seq_total_cells(client->pool) > 0;
96 }
97 
98 /* return pointer to client structure for specified id */
99 static struct snd_seq_client *clientptr(int clientid)
100 {
101 	if (clientid < 0 || clientid >= SNDRV_SEQ_MAX_CLIENTS) {
102 		pr_debug("ALSA: seq: oops. Trying to get pointer to client %d\n",
103 			   clientid);
104 		return NULL;
105 	}
106 	return clienttab[clientid];
107 }
108 
109 struct snd_seq_client *snd_seq_client_use_ptr(int clientid)
110 {
111 	unsigned long flags;
112 	struct snd_seq_client *client;
113 
114 	if (clientid < 0 || clientid >= SNDRV_SEQ_MAX_CLIENTS) {
115 		pr_debug("ALSA: seq: oops. Trying to get pointer to client %d\n",
116 			   clientid);
117 		return NULL;
118 	}
119 	spin_lock_irqsave(&clients_lock, flags);
120 	client = clientptr(clientid);
121 	if (client)
122 		goto __lock;
123 	if (clienttablock[clientid]) {
124 		spin_unlock_irqrestore(&clients_lock, flags);
125 		return NULL;
126 	}
127 	spin_unlock_irqrestore(&clients_lock, flags);
128 #ifdef CONFIG_MODULES
129 	if (!in_interrupt()) {
130 		static DECLARE_BITMAP(client_requested, SNDRV_SEQ_GLOBAL_CLIENTS);
131 		static DECLARE_BITMAP(card_requested, SNDRV_CARDS);
132 
133 		if (clientid < SNDRV_SEQ_GLOBAL_CLIENTS) {
134 			int idx;
135 
136 			if (!test_and_set_bit(clientid, client_requested)) {
137 				for (idx = 0; idx < 15; idx++) {
138 					if (seq_client_load[idx] < 0)
139 						break;
140 					if (seq_client_load[idx] == clientid) {
141 						request_module("snd-seq-client-%i",
142 							       clientid);
143 						break;
144 					}
145 				}
146 			}
147 		} else if (clientid < SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN) {
148 			int card = (clientid - SNDRV_SEQ_GLOBAL_CLIENTS) /
149 				SNDRV_SEQ_CLIENTS_PER_CARD;
150 			if (card < snd_ecards_limit) {
151 				if (!test_and_set_bit(card, card_requested))
152 					snd_request_card(card);
153 				snd_seq_device_load_drivers();
154 			}
155 		}
156 		spin_lock_irqsave(&clients_lock, flags);
157 		client = clientptr(clientid);
158 		if (client)
159 			goto __lock;
160 		spin_unlock_irqrestore(&clients_lock, flags);
161 	}
162 #endif
163 	return NULL;
164 
165       __lock:
166 	snd_use_lock_use(&client->use_lock);
167 	spin_unlock_irqrestore(&clients_lock, flags);
168 	return client;
169 }
170 
171 /* Take refcount and perform ioctl_mutex lock on the given client;
172  * used only for OSS sequencer
173  * Unlock via snd_seq_client_ioctl_unlock() below
174  */
175 bool snd_seq_client_ioctl_lock(int clientid)
176 {
177 	struct snd_seq_client *client;
178 
179 	client = snd_seq_client_use_ptr(clientid);
180 	if (!client)
181 		return false;
182 	mutex_lock(&client->ioctl_mutex);
183 	/* The client isn't unrefed here; see snd_seq_client_ioctl_unlock() */
184 	return true;
185 }
186 EXPORT_SYMBOL_GPL(snd_seq_client_ioctl_lock);
187 
188 /* Unlock and unref the given client; for OSS sequencer use only */
189 void snd_seq_client_ioctl_unlock(int clientid)
190 {
191 	struct snd_seq_client *client;
192 
193 	client = snd_seq_client_use_ptr(clientid);
194 	if (WARN_ON(!client))
195 		return;
196 	mutex_unlock(&client->ioctl_mutex);
197 	/* The doubly unrefs below are intentional; the first one releases the
198 	 * leftover from snd_seq_client_ioctl_lock() above, and the second one
199 	 * is for releasing snd_seq_client_use_ptr() in this function
200 	 */
201 	snd_seq_client_unlock(client);
202 	snd_seq_client_unlock(client);
203 }
204 EXPORT_SYMBOL_GPL(snd_seq_client_ioctl_unlock);
205 
206 static void usage_alloc(struct snd_seq_usage *res, int num)
207 {
208 	res->cur += num;
209 	if (res->cur > res->peak)
210 		res->peak = res->cur;
211 }
212 
213 static void usage_free(struct snd_seq_usage *res, int num)
214 {
215 	res->cur -= num;
216 }
217 
218 /* initialise data structures */
219 int __init client_init_data(void)
220 {
221 	/* zap out the client table */
222 	memset(&clienttablock, 0, sizeof(clienttablock));
223 	memset(&clienttab, 0, sizeof(clienttab));
224 	return 0;
225 }
226 
227 
228 static struct snd_seq_client *seq_create_client1(int client_index, int poolsize)
229 {
230 	int c;
231 	struct snd_seq_client *client;
232 
233 	/* init client data */
234 	client = kzalloc(sizeof(*client), GFP_KERNEL);
235 	if (client == NULL)
236 		return NULL;
237 	client->pool = snd_seq_pool_new(poolsize);
238 	if (client->pool == NULL) {
239 		kfree(client);
240 		return NULL;
241 	}
242 	client->type = NO_CLIENT;
243 	snd_use_lock_init(&client->use_lock);
244 	rwlock_init(&client->ports_lock);
245 	mutex_init(&client->ports_mutex);
246 	INIT_LIST_HEAD(&client->ports_list_head);
247 	mutex_init(&client->ioctl_mutex);
248 	client->ump_endpoint_port = -1;
249 
250 	/* find free slot in the client table */
251 	spin_lock_irq(&clients_lock);
252 	if (client_index < 0) {
253 		for (c = SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN;
254 		     c < SNDRV_SEQ_MAX_CLIENTS;
255 		     c++) {
256 			if (clienttab[c] || clienttablock[c])
257 				continue;
258 			clienttab[client->number = c] = client;
259 			spin_unlock_irq(&clients_lock);
260 			return client;
261 		}
262 	} else {
263 		if (clienttab[client_index] == NULL && !clienttablock[client_index]) {
264 			clienttab[client->number = client_index] = client;
265 			spin_unlock_irq(&clients_lock);
266 			return client;
267 		}
268 	}
269 	spin_unlock_irq(&clients_lock);
270 	snd_seq_pool_delete(&client->pool);
271 	kfree(client);
272 	return NULL;	/* no free slot found or busy, return failure code */
273 }
274 
275 
276 static int seq_free_client1(struct snd_seq_client *client)
277 {
278 	if (!client)
279 		return 0;
280 	spin_lock_irq(&clients_lock);
281 	clienttablock[client->number] = 1;
282 	clienttab[client->number] = NULL;
283 	spin_unlock_irq(&clients_lock);
284 	snd_seq_delete_all_ports(client);
285 	snd_seq_queue_client_leave(client->number);
286 	snd_use_lock_sync(&client->use_lock);
287 	if (client->pool)
288 		snd_seq_pool_delete(&client->pool);
289 	spin_lock_irq(&clients_lock);
290 	clienttablock[client->number] = 0;
291 	spin_unlock_irq(&clients_lock);
292 	return 0;
293 }
294 
295 
296 static void seq_free_client(struct snd_seq_client * client)
297 {
298 	mutex_lock(&register_mutex);
299 	switch (client->type) {
300 	case NO_CLIENT:
301 		pr_warn("ALSA: seq: Trying to free unused client %d\n",
302 			client->number);
303 		break;
304 	case USER_CLIENT:
305 	case KERNEL_CLIENT:
306 		seq_free_client1(client);
307 		usage_free(&client_usage, 1);
308 		break;
309 
310 	default:
311 		pr_err("ALSA: seq: Trying to free client %d with undefined type = %d\n",
312 			   client->number, client->type);
313 	}
314 	mutex_unlock(&register_mutex);
315 
316 	snd_seq_system_client_ev_client_exit(client->number);
317 }
318 
319 
320 
321 /* -------------------------------------------------------- */
322 
323 /* create a user client */
324 static int snd_seq_open(struct inode *inode, struct file *file)
325 {
326 	int c, mode;			/* client id */
327 	struct snd_seq_client *client;
328 	struct snd_seq_user_client *user;
329 	int err;
330 
331 	err = stream_open(inode, file);
332 	if (err < 0)
333 		return err;
334 
335 	mutex_lock(&register_mutex);
336 	client = seq_create_client1(-1, SNDRV_SEQ_DEFAULT_EVENTS);
337 	if (!client) {
338 		mutex_unlock(&register_mutex);
339 		return -ENOMEM;	/* failure code */
340 	}
341 
342 	mode = snd_seq_file_flags(file);
343 	if (mode & SNDRV_SEQ_LFLG_INPUT)
344 		client->accept_input = 1;
345 	if (mode & SNDRV_SEQ_LFLG_OUTPUT)
346 		client->accept_output = 1;
347 
348 	user = &client->data.user;
349 	user->fifo = NULL;
350 	user->fifo_pool_size = 0;
351 
352 	if (mode & SNDRV_SEQ_LFLG_INPUT) {
353 		user->fifo_pool_size = SNDRV_SEQ_DEFAULT_CLIENT_EVENTS;
354 		user->fifo = snd_seq_fifo_new(user->fifo_pool_size);
355 		if (user->fifo == NULL) {
356 			seq_free_client1(client);
357 			kfree(client);
358 			mutex_unlock(&register_mutex);
359 			return -ENOMEM;
360 		}
361 	}
362 
363 	usage_alloc(&client_usage, 1);
364 	client->type = USER_CLIENT;
365 	mutex_unlock(&register_mutex);
366 
367 	c = client->number;
368 	file->private_data = client;
369 
370 	/* fill client data */
371 	user->file = file;
372 	sprintf(client->name, "Client-%d", c);
373 	client->data.user.owner = get_pid(task_pid(current));
374 
375 	/* make others aware this new client */
376 	snd_seq_system_client_ev_client_start(c);
377 
378 	return 0;
379 }
380 
381 /* delete a user client */
382 static int snd_seq_release(struct inode *inode, struct file *file)
383 {
384 	struct snd_seq_client *client = file->private_data;
385 
386 	if (client) {
387 		seq_free_client(client);
388 		if (client->data.user.fifo)
389 			snd_seq_fifo_delete(&client->data.user.fifo);
390 #if IS_ENABLED(CONFIG_SND_SEQ_UMP)
391 		free_ump_info(client);
392 #endif
393 		put_pid(client->data.user.owner);
394 		kfree(client);
395 	}
396 
397 	return 0;
398 }
399 
400 static bool event_is_compatible(const struct snd_seq_client *client,
401 				const struct snd_seq_event *ev)
402 {
403 	if (snd_seq_ev_is_ump(ev) && !client->midi_version)
404 		return false;
405 	if (snd_seq_ev_is_ump(ev) && snd_seq_ev_is_variable(ev))
406 		return false;
407 	return true;
408 }
409 
410 /* handle client read() */
411 /* possible error values:
412  *	-ENXIO	invalid client or file open mode
413  *	-ENOSPC	FIFO overflow (the flag is cleared after this error report)
414  *	-EINVAL	no enough user-space buffer to write the whole event
415  *	-EFAULT	seg. fault during copy to user space
416  */
417 static ssize_t snd_seq_read(struct file *file, char __user *buf, size_t count,
418 			    loff_t *offset)
419 {
420 	struct snd_seq_client *client = file->private_data;
421 	struct snd_seq_fifo *fifo;
422 	size_t aligned_size;
423 	int err;
424 	long result = 0;
425 	struct snd_seq_event_cell *cell;
426 
427 	if (!(snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_INPUT))
428 		return -ENXIO;
429 
430 	if (!access_ok(buf, count))
431 		return -EFAULT;
432 
433 	/* check client structures are in place */
434 	if (snd_BUG_ON(!client))
435 		return -ENXIO;
436 
437 	if (!client->accept_input)
438 		return -ENXIO;
439 	fifo = client->data.user.fifo;
440 	if (!fifo)
441 		return -ENXIO;
442 
443 	if (atomic_read(&fifo->overflow) > 0) {
444 		/* buffer overflow is detected */
445 		snd_seq_fifo_clear(fifo);
446 		/* return error code */
447 		return -ENOSPC;
448 	}
449 
450 	cell = NULL;
451 	err = 0;
452 	snd_seq_fifo_lock(fifo);
453 
454 	if (IS_ENABLED(CONFIG_SND_SEQ_UMP) && client->midi_version > 0)
455 		aligned_size = sizeof(struct snd_seq_ump_event);
456 	else
457 		aligned_size = sizeof(struct snd_seq_event);
458 
459 	/* while data available in queue */
460 	while (count >= aligned_size) {
461 		int nonblock;
462 
463 		nonblock = (file->f_flags & O_NONBLOCK) || result > 0;
464 		err = snd_seq_fifo_cell_out(fifo, &cell, nonblock);
465 		if (err < 0)
466 			break;
467 		if (!event_is_compatible(client, &cell->event)) {
468 			snd_seq_cell_free(cell);
469 			cell = NULL;
470 			continue;
471 		}
472 		if (snd_seq_ev_is_variable(&cell->event)) {
473 			struct snd_seq_ump_event tmpev;
474 
475 			memcpy(&tmpev, &cell->event, aligned_size);
476 			tmpev.data.ext.len &= ~SNDRV_SEQ_EXT_MASK;
477 			if (copy_to_user(buf, &tmpev, aligned_size)) {
478 				err = -EFAULT;
479 				break;
480 			}
481 			count -= aligned_size;
482 			buf += aligned_size;
483 			err = snd_seq_expand_var_event(&cell->event, count,
484 						       (char __force *)buf, 0,
485 						       aligned_size);
486 			if (err < 0)
487 				break;
488 			result += err;
489 			count -= err;
490 			buf += err;
491 		} else {
492 			if (copy_to_user(buf, &cell->event, aligned_size)) {
493 				err = -EFAULT;
494 				break;
495 			}
496 			count -= aligned_size;
497 			buf += aligned_size;
498 		}
499 		snd_seq_cell_free(cell);
500 		cell = NULL; /* to be sure */
501 		result += aligned_size;
502 	}
503 
504 	if (err < 0) {
505 		if (cell)
506 			snd_seq_fifo_cell_putback(fifo, cell);
507 		if (err == -EAGAIN && result > 0)
508 			err = 0;
509 	}
510 	snd_seq_fifo_unlock(fifo);
511 
512 	return (err < 0) ? err : result;
513 }
514 
515 
516 /*
517  * check access permission to the port
518  */
519 static int check_port_perm(struct snd_seq_client_port *port, unsigned int flags)
520 {
521 	if ((port->capability & flags) != flags)
522 		return 0;
523 	return flags;
524 }
525 
526 /*
527  * check if the destination client is available, and return the pointer
528  */
529 static struct snd_seq_client *get_event_dest_client(struct snd_seq_event *event)
530 {
531 	struct snd_seq_client *dest;
532 
533 	dest = snd_seq_client_use_ptr(event->dest.client);
534 	if (dest == NULL)
535 		return NULL;
536 	if (! dest->accept_input)
537 		goto __not_avail;
538 	if (snd_seq_ev_is_ump(event))
539 		return dest; /* ok - no filter checks */
540 
541 	if ((dest->filter & SNDRV_SEQ_FILTER_USE_EVENT) &&
542 	    ! test_bit(event->type, dest->event_filter))
543 		goto __not_avail;
544 
545 	return dest; /* ok - accessible */
546 __not_avail:
547 	snd_seq_client_unlock(dest);
548 	return NULL;
549 }
550 
551 
552 /*
553  * Return the error event.
554  *
555  * If the receiver client is a user client, the original event is
556  * encapsulated in SNDRV_SEQ_EVENT_BOUNCE as variable length event.  If
557  * the original event is also variable length, the external data is
558  * copied after the event record.
559  * If the receiver client is a kernel client, the original event is
560  * quoted in SNDRV_SEQ_EVENT_KERNEL_ERROR, since this requires no extra
561  * kmalloc.
562  */
563 static int bounce_error_event(struct snd_seq_client *client,
564 			      struct snd_seq_event *event,
565 			      int err, int atomic, int hop)
566 {
567 	struct snd_seq_event bounce_ev;
568 	int result;
569 
570 	if (client == NULL ||
571 	    ! (client->filter & SNDRV_SEQ_FILTER_BOUNCE) ||
572 	    ! client->accept_input)
573 		return 0; /* ignored */
574 
575 	/* set up quoted error */
576 	memset(&bounce_ev, 0, sizeof(bounce_ev));
577 	bounce_ev.type = SNDRV_SEQ_EVENT_KERNEL_ERROR;
578 	bounce_ev.flags = SNDRV_SEQ_EVENT_LENGTH_FIXED;
579 	bounce_ev.queue = SNDRV_SEQ_QUEUE_DIRECT;
580 	bounce_ev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
581 	bounce_ev.source.port = SNDRV_SEQ_PORT_SYSTEM_ANNOUNCE;
582 	bounce_ev.dest.client = client->number;
583 	bounce_ev.dest.port = event->source.port;
584 	bounce_ev.data.quote.origin = event->dest;
585 	bounce_ev.data.quote.event = event;
586 	bounce_ev.data.quote.value = -err; /* use positive value */
587 	result = snd_seq_deliver_single_event(NULL, &bounce_ev, atomic, hop + 1);
588 	if (result < 0) {
589 		client->event_lost++;
590 		return result;
591 	}
592 
593 	return result;
594 }
595 
596 
597 /*
598  * rewrite the time-stamp of the event record with the curren time
599  * of the given queue.
600  * return non-zero if updated.
601  */
602 static int update_timestamp_of_queue(struct snd_seq_event *event,
603 				     int queue, int real_time)
604 {
605 	struct snd_seq_queue *q;
606 
607 	q = queueptr(queue);
608 	if (! q)
609 		return 0;
610 	event->queue = queue;
611 	event->flags &= ~SNDRV_SEQ_TIME_STAMP_MASK;
612 	if (real_time) {
613 		event->time.time = snd_seq_timer_get_cur_time(q->timer, true);
614 		event->flags |= SNDRV_SEQ_TIME_STAMP_REAL;
615 	} else {
616 		event->time.tick = snd_seq_timer_get_cur_tick(q->timer);
617 		event->flags |= SNDRV_SEQ_TIME_STAMP_TICK;
618 	}
619 	queuefree(q);
620 	return 1;
621 }
622 
623 /* deliver a single event; called from below and UMP converter */
624 int __snd_seq_deliver_single_event(struct snd_seq_client *dest,
625 				   struct snd_seq_client_port *dest_port,
626 				   struct snd_seq_event *event,
627 				   int atomic, int hop)
628 {
629 	switch (dest->type) {
630 	case USER_CLIENT:
631 		if (!dest->data.user.fifo)
632 			return 0;
633 		return snd_seq_fifo_event_in(dest->data.user.fifo, event);
634 	case KERNEL_CLIENT:
635 		if (!dest_port->event_input)
636 			return 0;
637 		return dest_port->event_input(event,
638 					      snd_seq_ev_is_direct(event),
639 					      dest_port->private_data,
640 					      atomic, hop);
641 	}
642 	return 0;
643 }
644 
645 /*
646  * deliver an event to the specified destination.
647  * if filter is non-zero, client filter bitmap is tested.
648  *
649  *  RETURN VALUE: 0 : if succeeded
650  *		 <0 : error
651  */
652 static int snd_seq_deliver_single_event(struct snd_seq_client *client,
653 					struct snd_seq_event *event,
654 					int atomic, int hop)
655 {
656 	struct snd_seq_client *dest = NULL;
657 	struct snd_seq_client_port *dest_port = NULL;
658 	int result = -ENOENT;
659 	int direct;
660 
661 	direct = snd_seq_ev_is_direct(event);
662 
663 	dest = get_event_dest_client(event);
664 	if (dest == NULL)
665 		goto __skip;
666 	dest_port = snd_seq_port_use_ptr(dest, event->dest.port);
667 	if (dest_port == NULL)
668 		goto __skip;
669 
670 	/* check permission */
671 	if (! check_port_perm(dest_port, SNDRV_SEQ_PORT_CAP_WRITE)) {
672 		result = -EPERM;
673 		goto __skip;
674 	}
675 
676 	if (dest_port->timestamping)
677 		update_timestamp_of_queue(event, dest_port->time_queue,
678 					  dest_port->time_real);
679 
680 #if IS_ENABLED(CONFIG_SND_SEQ_UMP)
681 	if (snd_seq_ev_is_ump(event)) {
682 		if (!(dest->filter & SNDRV_SEQ_FILTER_NO_CONVERT)) {
683 			result = snd_seq_deliver_from_ump(client, dest, dest_port,
684 							  event, atomic, hop);
685 			goto __skip;
686 		} else if (dest->type == USER_CLIENT &&
687 			   !snd_seq_client_is_ump(dest)) {
688 			result = 0; // drop the event
689 			goto __skip;
690 		}
691 	} else if (snd_seq_client_is_ump(dest)) {
692 		if (!(dest->filter & SNDRV_SEQ_FILTER_NO_CONVERT)) {
693 			result = snd_seq_deliver_to_ump(client, dest, dest_port,
694 							event, atomic, hop);
695 			goto __skip;
696 		}
697 	}
698 #endif /* CONFIG_SND_SEQ_UMP */
699 
700 	result = __snd_seq_deliver_single_event(dest, dest_port, event,
701 						atomic, hop);
702 
703   __skip:
704 	if (dest_port)
705 		snd_seq_port_unlock(dest_port);
706 	if (dest)
707 		snd_seq_client_unlock(dest);
708 
709 	if (result < 0 && !direct) {
710 		result = bounce_error_event(client, event, result, atomic, hop);
711 	}
712 	return result;
713 }
714 
715 
716 /*
717  * send the event to all subscribers:
718  */
719 static int __deliver_to_subscribers(struct snd_seq_client *client,
720 				    struct snd_seq_event *event,
721 				    struct snd_seq_client_port *src_port,
722 				    int atomic, int hop)
723 {
724 	struct snd_seq_subscribers *subs;
725 	int err, result = 0, num_ev = 0;
726 	union __snd_seq_event event_saved;
727 	size_t saved_size;
728 	struct snd_seq_port_subs_info *grp;
729 
730 	/* save original event record */
731 	saved_size = snd_seq_event_packet_size(event);
732 	memcpy(&event_saved, event, saved_size);
733 	grp = &src_port->c_src;
734 
735 	/* lock list */
736 	if (atomic)
737 		read_lock(&grp->list_lock);
738 	else
739 		down_read_nested(&grp->list_mutex, hop);
740 	list_for_each_entry(subs, &grp->list_head, src_list) {
741 		/* both ports ready? */
742 		if (atomic_read(&subs->ref_count) != 2)
743 			continue;
744 		event->dest = subs->info.dest;
745 		if (subs->info.flags & SNDRV_SEQ_PORT_SUBS_TIMESTAMP)
746 			/* convert time according to flag with subscription */
747 			update_timestamp_of_queue(event, subs->info.queue,
748 						  subs->info.flags & SNDRV_SEQ_PORT_SUBS_TIME_REAL);
749 		err = snd_seq_deliver_single_event(client, event, atomic, hop);
750 		if (err < 0) {
751 			/* save first error that occurs and continue */
752 			if (!result)
753 				result = err;
754 			continue;
755 		}
756 		num_ev++;
757 		/* restore original event record */
758 		memcpy(event, &event_saved, saved_size);
759 	}
760 	if (atomic)
761 		read_unlock(&grp->list_lock);
762 	else
763 		up_read(&grp->list_mutex);
764 	memcpy(event, &event_saved, saved_size);
765 	return (result < 0) ? result : num_ev;
766 }
767 
768 static int deliver_to_subscribers(struct snd_seq_client *client,
769 				  struct snd_seq_event *event,
770 				  int atomic, int hop)
771 {
772 	struct snd_seq_client_port *src_port;
773 	int ret = 0, ret2;
774 
775 	src_port = snd_seq_port_use_ptr(client, event->source.port);
776 	if (src_port) {
777 		ret = __deliver_to_subscribers(client, event, src_port, atomic, hop);
778 		snd_seq_port_unlock(src_port);
779 	}
780 
781 	if (client->ump_endpoint_port < 0 ||
782 	    event->source.port == client->ump_endpoint_port)
783 		return ret;
784 
785 	src_port = snd_seq_port_use_ptr(client, client->ump_endpoint_port);
786 	if (!src_port)
787 		return ret;
788 	ret2 = __deliver_to_subscribers(client, event, src_port, atomic, hop);
789 	snd_seq_port_unlock(src_port);
790 	return ret2 < 0 ? ret2 : ret;
791 }
792 
793 /* deliver an event to the destination port(s).
794  * if the event is to subscribers or broadcast, the event is dispatched
795  * to multiple targets.
796  *
797  * RETURN VALUE: n > 0  : the number of delivered events.
798  *               n == 0 : the event was not passed to any client.
799  *               n < 0  : error - event was not processed.
800  */
801 static int snd_seq_deliver_event(struct snd_seq_client *client, struct snd_seq_event *event,
802 				 int atomic, int hop)
803 {
804 	int result;
805 
806 	hop++;
807 	if (hop >= SNDRV_SEQ_MAX_HOPS) {
808 		pr_debug("ALSA: seq: too long delivery path (%d:%d->%d:%d)\n",
809 			   event->source.client, event->source.port,
810 			   event->dest.client, event->dest.port);
811 		return -EMLINK;
812 	}
813 
814 	if (snd_seq_ev_is_variable(event) &&
815 	    snd_BUG_ON(atomic && (event->data.ext.len & SNDRV_SEQ_EXT_USRPTR)))
816 		return -EINVAL;
817 
818 	if (event->queue == SNDRV_SEQ_ADDRESS_SUBSCRIBERS ||
819 	    event->dest.client == SNDRV_SEQ_ADDRESS_SUBSCRIBERS)
820 		result = deliver_to_subscribers(client, event, atomic, hop);
821 	else
822 		result = snd_seq_deliver_single_event(client, event, atomic, hop);
823 
824 	return result;
825 }
826 
827 /*
828  * dispatch an event cell:
829  * This function is called only from queue check routines in timer
830  * interrupts or after enqueued.
831  * The event cell shall be released or re-queued in this function.
832  *
833  * RETURN VALUE: n > 0  : the number of delivered events.
834  *		 n == 0 : the event was not passed to any client.
835  *		 n < 0  : error - event was not processed.
836  */
837 int snd_seq_dispatch_event(struct snd_seq_event_cell *cell, int atomic, int hop)
838 {
839 	struct snd_seq_client *client;
840 	int result;
841 
842 	if (snd_BUG_ON(!cell))
843 		return -EINVAL;
844 
845 	client = snd_seq_client_use_ptr(cell->event.source.client);
846 	if (client == NULL) {
847 		snd_seq_cell_free(cell); /* release this cell */
848 		return -EINVAL;
849 	}
850 
851 	if (!snd_seq_ev_is_ump(&cell->event) &&
852 	    cell->event.type == SNDRV_SEQ_EVENT_NOTE) {
853 		/* NOTE event:
854 		 * the event cell is re-used as a NOTE-OFF event and
855 		 * enqueued again.
856 		 */
857 		struct snd_seq_event tmpev, *ev;
858 
859 		/* reserve this event to enqueue note-off later */
860 		tmpev = cell->event;
861 		tmpev.type = SNDRV_SEQ_EVENT_NOTEON;
862 		result = snd_seq_deliver_event(client, &tmpev, atomic, hop);
863 
864 		/*
865 		 * This was originally a note event.  We now re-use the
866 		 * cell for the note-off event.
867 		 */
868 
869 		ev = &cell->event;
870 		ev->type = SNDRV_SEQ_EVENT_NOTEOFF;
871 		ev->flags |= SNDRV_SEQ_PRIORITY_HIGH;
872 
873 		/* add the duration time */
874 		switch (ev->flags & SNDRV_SEQ_TIME_STAMP_MASK) {
875 		case SNDRV_SEQ_TIME_STAMP_TICK:
876 			cell->event.time.tick += ev->data.note.duration;
877 			break;
878 		case SNDRV_SEQ_TIME_STAMP_REAL:
879 			/* unit for duration is ms */
880 			ev->time.time.tv_nsec += 1000000 * (ev->data.note.duration % 1000);
881 			ev->time.time.tv_sec += ev->data.note.duration / 1000 +
882 						ev->time.time.tv_nsec / 1000000000;
883 			ev->time.time.tv_nsec %= 1000000000;
884 			break;
885 		}
886 		ev->data.note.velocity = ev->data.note.off_velocity;
887 
888 		/* Now queue this cell as the note off event */
889 		if (snd_seq_enqueue_event(cell, atomic, hop) < 0)
890 			snd_seq_cell_free(cell); /* release this cell */
891 
892 	} else {
893 		/* Normal events:
894 		 * event cell is freed after processing the event
895 		 */
896 
897 		result = snd_seq_deliver_event(client, &cell->event, atomic, hop);
898 		snd_seq_cell_free(cell);
899 	}
900 
901 	snd_seq_client_unlock(client);
902 	return result;
903 }
904 
905 
906 /* Allocate a cell from client pool and enqueue it to queue:
907  * if pool is empty and blocking is TRUE, sleep until a new cell is
908  * available.
909  */
910 static int snd_seq_client_enqueue_event(struct snd_seq_client *client,
911 					struct snd_seq_event *event,
912 					struct file *file, int blocking,
913 					int atomic, int hop,
914 					struct mutex *mutexp)
915 {
916 	struct snd_seq_event_cell *cell;
917 	int err;
918 
919 	/* special queue values - force direct passing */
920 	if (event->queue == SNDRV_SEQ_ADDRESS_SUBSCRIBERS) {
921 		event->dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
922 		event->queue = SNDRV_SEQ_QUEUE_DIRECT;
923 	} else if (event->dest.client == SNDRV_SEQ_ADDRESS_SUBSCRIBERS) {
924 		/* check presence of source port */
925 		struct snd_seq_client_port *src_port = snd_seq_port_use_ptr(client, event->source.port);
926 		if (src_port == NULL)
927 			return -EINVAL;
928 		snd_seq_port_unlock(src_port);
929 	}
930 
931 	/* direct event processing without enqueued */
932 	if (snd_seq_ev_is_direct(event)) {
933 		if (!snd_seq_ev_is_ump(event) &&
934 		    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,
947 				file, mutexp);
948 	if (err < 0)
949 		return err;
950 
951 	/* we got a cell. enqueue it. */
952 	err = snd_seq_enqueue_event(cell, atomic, hop);
953 	if (err < 0) {
954 		snd_seq_cell_free(cell);
955 		return err;
956 	}
957 
958 	return 0;
959 }
960 
961 
962 /*
963  * check validity of event type and data length.
964  * return non-zero if invalid.
965  */
966 static int check_event_type_and_length(struct snd_seq_event *ev)
967 {
968 	switch (snd_seq_ev_length_type(ev)) {
969 	case SNDRV_SEQ_EVENT_LENGTH_FIXED:
970 		if (snd_seq_ev_is_variable_type(ev))
971 			return -EINVAL;
972 		break;
973 	case SNDRV_SEQ_EVENT_LENGTH_VARIABLE:
974 		if (! snd_seq_ev_is_variable_type(ev) ||
975 		    (ev->data.ext.len & ~SNDRV_SEQ_EXT_MASK) >= SNDRV_SEQ_MAX_EVENT_LEN)
976 			return -EINVAL;
977 		break;
978 	case SNDRV_SEQ_EVENT_LENGTH_VARUSR:
979 		if (! snd_seq_ev_is_direct(ev))
980 			return -EINVAL;
981 		break;
982 	}
983 	return 0;
984 }
985 
986 
987 /* handle write() */
988 /* possible error values:
989  *	-ENXIO	invalid client or file open mode
990  *	-ENOMEM	malloc failed
991  *	-EFAULT	seg. fault during copy from user space
992  *	-EINVAL	invalid event
993  *	-EAGAIN	no space in output pool
994  *	-EINTR	interrupts while sleep
995  *	-EMLINK	too many hops
996  *	others	depends on return value from driver callback
997  */
998 static ssize_t snd_seq_write(struct file *file, const char __user *buf,
999 			     size_t count, loff_t *offset)
1000 {
1001 	struct snd_seq_client *client = file->private_data;
1002 	int written = 0, len;
1003 	int err, handled;
1004 	union __snd_seq_event __event;
1005 	struct snd_seq_event *ev = &__event.legacy;
1006 
1007 	if (!(snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_OUTPUT))
1008 		return -ENXIO;
1009 
1010 	/* check client structures are in place */
1011 	if (snd_BUG_ON(!client))
1012 		return -ENXIO;
1013 
1014 	if (!client->accept_output || client->pool == NULL)
1015 		return -ENXIO;
1016 
1017  repeat:
1018 	handled = 0;
1019 	/* allocate the pool now if the pool is not allocated yet */
1020 	mutex_lock(&client->ioctl_mutex);
1021 	if (client->pool->size > 0 && !snd_seq_write_pool_allocated(client)) {
1022 		err = snd_seq_pool_init(client->pool);
1023 		if (err < 0)
1024 			goto out;
1025 	}
1026 
1027 	/* only process whole events */
1028 	err = -EINVAL;
1029 	while (count >= sizeof(struct snd_seq_event)) {
1030 		/* Read in the event header from the user */
1031 		len = sizeof(struct snd_seq_event);
1032 		if (copy_from_user(ev, buf, len)) {
1033 			err = -EFAULT;
1034 			break;
1035 		}
1036 		/* read in the rest bytes for UMP events */
1037 		if (snd_seq_ev_is_ump(ev)) {
1038 			if (count < sizeof(struct snd_seq_ump_event))
1039 				break;
1040 			if (copy_from_user((char *)ev + len, buf + len,
1041 					   sizeof(struct snd_seq_ump_event) - len)) {
1042 				err = -EFAULT;
1043 				break;
1044 			}
1045 			len = sizeof(struct snd_seq_ump_event);
1046 		}
1047 
1048 		ev->source.client = client->number;	/* fill in client number */
1049 		/* Check for extension data length */
1050 		if (check_event_type_and_length(ev)) {
1051 			err = -EINVAL;
1052 			break;
1053 		}
1054 
1055 		if (!event_is_compatible(client, ev)) {
1056 			err = -EINVAL;
1057 			break;
1058 		}
1059 
1060 		/* check for special events */
1061 		if (!snd_seq_ev_is_ump(ev)) {
1062 			if (ev->type == SNDRV_SEQ_EVENT_NONE)
1063 				goto __skip_event;
1064 			else if (snd_seq_ev_is_reserved(ev)) {
1065 				err = -EINVAL;
1066 				break;
1067 			}
1068 		}
1069 
1070 		if (snd_seq_ev_is_variable(ev)) {
1071 			int extlen = ev->data.ext.len & ~SNDRV_SEQ_EXT_MASK;
1072 			if ((size_t)(extlen + len) > count) {
1073 				/* back out, will get an error this time or next */
1074 				err = -EINVAL;
1075 				break;
1076 			}
1077 			/* set user space pointer */
1078 			ev->data.ext.len = extlen | SNDRV_SEQ_EXT_USRPTR;
1079 			ev->data.ext.ptr = (char __force *)buf + len;
1080 			len += extlen; /* increment data length */
1081 		} else {
1082 #ifdef CONFIG_COMPAT
1083 			if (client->convert32 && snd_seq_ev_is_varusr(ev))
1084 				ev->data.ext.ptr =
1085 					(void __force *)compat_ptr(ev->data.raw32.d[1]);
1086 #endif
1087 		}
1088 
1089 		/* ok, enqueue it */
1090 		err = snd_seq_client_enqueue_event(client, ev, file,
1091 						   !(file->f_flags & O_NONBLOCK),
1092 						   0, 0, &client->ioctl_mutex);
1093 		if (err < 0)
1094 			break;
1095 		handled++;
1096 
1097 	__skip_event:
1098 		/* Update pointers and counts */
1099 		count -= len;
1100 		buf += len;
1101 		written += len;
1102 
1103 		/* let's have a coffee break if too many events are queued */
1104 		if (++handled >= 200) {
1105 			mutex_unlock(&client->ioctl_mutex);
1106 			goto repeat;
1107 		}
1108 	}
1109 
1110  out:
1111 	mutex_unlock(&client->ioctl_mutex);
1112 	return written ? written : err;
1113 }
1114 
1115 
1116 /*
1117  * handle polling
1118  */
1119 static __poll_t snd_seq_poll(struct file *file, poll_table * wait)
1120 {
1121 	struct snd_seq_client *client = file->private_data;
1122 	__poll_t mask = 0;
1123 
1124 	/* check client structures are in place */
1125 	if (snd_BUG_ON(!client))
1126 		return EPOLLERR;
1127 
1128 	if ((snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_INPUT) &&
1129 	    client->data.user.fifo) {
1130 
1131 		/* check if data is available in the outqueue */
1132 		if (snd_seq_fifo_poll_wait(client->data.user.fifo, file, wait))
1133 			mask |= EPOLLIN | EPOLLRDNORM;
1134 	}
1135 
1136 	if (snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_OUTPUT) {
1137 
1138 		/* check if data is available in the pool */
1139 		if (!snd_seq_write_pool_allocated(client) ||
1140 		    snd_seq_pool_poll_wait(client->pool, file, wait))
1141 			mask |= EPOLLOUT | EPOLLWRNORM;
1142 	}
1143 
1144 	return mask;
1145 }
1146 
1147 
1148 /*-----------------------------------------------------*/
1149 
1150 static int snd_seq_ioctl_pversion(struct snd_seq_client *client, void *arg)
1151 {
1152 	int *pversion = arg;
1153 
1154 	*pversion = SNDRV_SEQ_VERSION;
1155 	return 0;
1156 }
1157 
1158 static int snd_seq_ioctl_user_pversion(struct snd_seq_client *client, void *arg)
1159 {
1160 	client->user_pversion = *(unsigned int *)arg;
1161 	return 0;
1162 }
1163 
1164 static int snd_seq_ioctl_client_id(struct snd_seq_client *client, void *arg)
1165 {
1166 	int *client_id = arg;
1167 
1168 	*client_id = client->number;
1169 	return 0;
1170 }
1171 
1172 /* SYSTEM_INFO ioctl() */
1173 static int snd_seq_ioctl_system_info(struct snd_seq_client *client, void *arg)
1174 {
1175 	struct snd_seq_system_info *info = arg;
1176 
1177 	memset(info, 0, sizeof(*info));
1178 	/* fill the info fields */
1179 	info->queues = SNDRV_SEQ_MAX_QUEUES;
1180 	info->clients = SNDRV_SEQ_MAX_CLIENTS;
1181 	info->ports = SNDRV_SEQ_MAX_PORTS;
1182 	info->channels = 256;	/* fixed limit */
1183 	info->cur_clients = client_usage.cur;
1184 	info->cur_queues = snd_seq_queue_get_cur_queues();
1185 
1186 	return 0;
1187 }
1188 
1189 
1190 /* RUNNING_MODE ioctl() */
1191 static int snd_seq_ioctl_running_mode(struct snd_seq_client *client, void  *arg)
1192 {
1193 	struct snd_seq_running_info *info = arg;
1194 	struct snd_seq_client *cptr;
1195 	int err = 0;
1196 
1197 	/* requested client number */
1198 	cptr = snd_seq_client_use_ptr(info->client);
1199 	if (cptr == NULL)
1200 		return -ENOENT;		/* don't change !!! */
1201 
1202 #ifdef SNDRV_BIG_ENDIAN
1203 	if (!info->big_endian) {
1204 		err = -EINVAL;
1205 		goto __err;
1206 	}
1207 #else
1208 	if (info->big_endian) {
1209 		err = -EINVAL;
1210 		goto __err;
1211 	}
1212 
1213 #endif
1214 	if (info->cpu_mode > sizeof(long)) {
1215 		err = -EINVAL;
1216 		goto __err;
1217 	}
1218 	cptr->convert32 = (info->cpu_mode < sizeof(long));
1219  __err:
1220 	snd_seq_client_unlock(cptr);
1221 	return err;
1222 }
1223 
1224 /* CLIENT_INFO ioctl() */
1225 static void get_client_info(struct snd_seq_client *cptr,
1226 			    struct snd_seq_client_info *info)
1227 {
1228 	info->client = cptr->number;
1229 
1230 	/* fill the info fields */
1231 	info->type = cptr->type;
1232 	strcpy(info->name, cptr->name);
1233 	info->filter = cptr->filter;
1234 	info->event_lost = cptr->event_lost;
1235 	memcpy(info->event_filter, cptr->event_filter, 32);
1236 	info->group_filter = cptr->group_filter;
1237 	info->num_ports = cptr->num_ports;
1238 
1239 	if (cptr->type == USER_CLIENT)
1240 		info->pid = pid_vnr(cptr->data.user.owner);
1241 	else
1242 		info->pid = -1;
1243 
1244 	if (cptr->type == KERNEL_CLIENT)
1245 		info->card = cptr->data.kernel.card ? cptr->data.kernel.card->number : -1;
1246 	else
1247 		info->card = -1;
1248 
1249 	info->midi_version = cptr->midi_version;
1250 	memset(info->reserved, 0, sizeof(info->reserved));
1251 }
1252 
1253 static int snd_seq_ioctl_get_client_info(struct snd_seq_client *client,
1254 					 void *arg)
1255 {
1256 	struct snd_seq_client_info *client_info = arg;
1257 	struct snd_seq_client *cptr;
1258 
1259 	/* requested client number */
1260 	cptr = snd_seq_client_use_ptr(client_info->client);
1261 	if (cptr == NULL)
1262 		return -ENOENT;		/* don't change !!! */
1263 
1264 	get_client_info(cptr, client_info);
1265 	snd_seq_client_unlock(cptr);
1266 
1267 	return 0;
1268 }
1269 
1270 
1271 /* CLIENT_INFO ioctl() */
1272 static int snd_seq_ioctl_set_client_info(struct snd_seq_client *client,
1273 					 void *arg)
1274 {
1275 	struct snd_seq_client_info *client_info = arg;
1276 
1277 	/* it is not allowed to set the info fields for an another client */
1278 	if (client->number != client_info->client)
1279 		return -EPERM;
1280 	/* also client type must be set now */
1281 	if (client->type != client_info->type)
1282 		return -EINVAL;
1283 
1284 	if (client->user_pversion >= SNDRV_PROTOCOL_VERSION(1, 0, 3)) {
1285 		/* check validity of midi_version field */
1286 		if (client_info->midi_version > SNDRV_SEQ_CLIENT_UMP_MIDI_2_0)
1287 			return -EINVAL;
1288 
1289 		/* check if UMP is supported in kernel */
1290 		if (!IS_ENABLED(CONFIG_SND_SEQ_UMP) &&
1291 		    client_info->midi_version > 0)
1292 			return -EINVAL;
1293 	}
1294 
1295 	/* fill the info fields */
1296 	if (client_info->name[0])
1297 		strscpy(client->name, client_info->name, sizeof(client->name));
1298 
1299 	client->filter = client_info->filter;
1300 	client->event_lost = client_info->event_lost;
1301 	if (client->user_pversion >= SNDRV_PROTOCOL_VERSION(1, 0, 3))
1302 		client->midi_version = client_info->midi_version;
1303 	memcpy(client->event_filter, client_info->event_filter, 32);
1304 	client->group_filter = client_info->group_filter;
1305 
1306 	/* notify the change */
1307 	snd_seq_system_client_ev_client_change(client->number);
1308 
1309 	return 0;
1310 }
1311 
1312 
1313 /*
1314  * CREATE PORT ioctl()
1315  */
1316 static int snd_seq_ioctl_create_port(struct snd_seq_client *client, void *arg)
1317 {
1318 	struct snd_seq_port_info *info = arg;
1319 	struct snd_seq_client_port *port;
1320 	struct snd_seq_port_callback *callback;
1321 	int port_idx, err;
1322 
1323 	/* it is not allowed to create the port for an another client */
1324 	if (info->addr.client != client->number)
1325 		return -EPERM;
1326 	if (client->type == USER_CLIENT && info->kernel)
1327 		return -EINVAL;
1328 	if ((info->capability & SNDRV_SEQ_PORT_CAP_UMP_ENDPOINT) &&
1329 	    client->ump_endpoint_port >= 0)
1330 		return -EBUSY;
1331 
1332 	if (info->flags & SNDRV_SEQ_PORT_FLG_GIVEN_PORT)
1333 		port_idx = info->addr.port;
1334 	else
1335 		port_idx = -1;
1336 	if (port_idx >= SNDRV_SEQ_ADDRESS_UNKNOWN)
1337 		return -EINVAL;
1338 	err = snd_seq_create_port(client, port_idx, &port);
1339 	if (err < 0)
1340 		return err;
1341 
1342 	if (client->type == KERNEL_CLIENT) {
1343 		callback = info->kernel;
1344 		if (callback) {
1345 			if (callback->owner)
1346 				port->owner = callback->owner;
1347 			port->private_data = callback->private_data;
1348 			port->private_free = callback->private_free;
1349 			port->event_input = callback->event_input;
1350 			port->c_src.open = callback->subscribe;
1351 			port->c_src.close = callback->unsubscribe;
1352 			port->c_dest.open = callback->use;
1353 			port->c_dest.close = callback->unuse;
1354 		}
1355 	}
1356 
1357 	info->addr = port->addr;
1358 
1359 	snd_seq_set_port_info(port, info);
1360 	if (info->capability & SNDRV_SEQ_PORT_CAP_UMP_ENDPOINT)
1361 		client->ump_endpoint_port = port->addr.port;
1362 	snd_seq_system_client_ev_port_start(port->addr.client, port->addr.port);
1363 	snd_seq_port_unlock(port);
1364 
1365 	return 0;
1366 }
1367 
1368 /*
1369  * DELETE PORT ioctl()
1370  */
1371 static int snd_seq_ioctl_delete_port(struct snd_seq_client *client, void *arg)
1372 {
1373 	struct snd_seq_port_info *info = arg;
1374 	int err;
1375 
1376 	/* it is not allowed to remove the port for an another client */
1377 	if (info->addr.client != client->number)
1378 		return -EPERM;
1379 
1380 	err = snd_seq_delete_port(client, info->addr.port);
1381 	if (err >= 0) {
1382 		if (client->ump_endpoint_port == info->addr.port)
1383 			client->ump_endpoint_port = -1;
1384 		snd_seq_system_client_ev_port_exit(client->number, info->addr.port);
1385 	}
1386 	return err;
1387 }
1388 
1389 
1390 /*
1391  * GET_PORT_INFO ioctl() (on any client)
1392  */
1393 static int snd_seq_ioctl_get_port_info(struct snd_seq_client *client, void *arg)
1394 {
1395 	struct snd_seq_port_info *info = arg;
1396 	struct snd_seq_client *cptr;
1397 	struct snd_seq_client_port *port;
1398 
1399 	cptr = snd_seq_client_use_ptr(info->addr.client);
1400 	if (cptr == NULL)
1401 		return -ENXIO;
1402 
1403 	port = snd_seq_port_use_ptr(cptr, info->addr.port);
1404 	if (port == NULL) {
1405 		snd_seq_client_unlock(cptr);
1406 		return -ENOENT;			/* don't change */
1407 	}
1408 
1409 	/* get port info */
1410 	snd_seq_get_port_info(port, info);
1411 	snd_seq_port_unlock(port);
1412 	snd_seq_client_unlock(cptr);
1413 
1414 	return 0;
1415 }
1416 
1417 
1418 /*
1419  * SET_PORT_INFO ioctl() (only ports on this/own client)
1420  */
1421 static int snd_seq_ioctl_set_port_info(struct snd_seq_client *client, void *arg)
1422 {
1423 	struct snd_seq_port_info *info = arg;
1424 	struct snd_seq_client_port *port;
1425 
1426 	if (info->addr.client != client->number) /* only set our own ports ! */
1427 		return -EPERM;
1428 	port = snd_seq_port_use_ptr(client, info->addr.port);
1429 	if (port) {
1430 		snd_seq_set_port_info(port, info);
1431 		snd_seq_port_unlock(port);
1432 		/* notify the change */
1433 		snd_seq_system_client_ev_port_change(info->addr.client,
1434 						     info->addr.port);
1435 	}
1436 	return 0;
1437 }
1438 
1439 
1440 /*
1441  * port subscription (connection)
1442  */
1443 #define PERM_RD		(SNDRV_SEQ_PORT_CAP_READ|SNDRV_SEQ_PORT_CAP_SUBS_READ)
1444 #define PERM_WR		(SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_SUBS_WRITE)
1445 
1446 static int check_subscription_permission(struct snd_seq_client *client,
1447 					 struct snd_seq_client_port *sport,
1448 					 struct snd_seq_client_port *dport,
1449 					 struct snd_seq_port_subscribe *subs)
1450 {
1451 	if (client->number != subs->sender.client &&
1452 	    client->number != subs->dest.client) {
1453 		/* connection by third client - check export permission */
1454 		if (check_port_perm(sport, SNDRV_SEQ_PORT_CAP_NO_EXPORT))
1455 			return -EPERM;
1456 		if (check_port_perm(dport, SNDRV_SEQ_PORT_CAP_NO_EXPORT))
1457 			return -EPERM;
1458 	}
1459 
1460 	/* check read permission */
1461 	/* if sender or receiver is the subscribing client itself,
1462 	 * no permission check is necessary
1463 	 */
1464 	if (client->number != subs->sender.client) {
1465 		if (! check_port_perm(sport, PERM_RD))
1466 			return -EPERM;
1467 	}
1468 	/* check write permission */
1469 	if (client->number != subs->dest.client) {
1470 		if (! check_port_perm(dport, PERM_WR))
1471 			return -EPERM;
1472 	}
1473 	return 0;
1474 }
1475 
1476 /*
1477  * send an subscription notify event to user client:
1478  * client must be user client.
1479  */
1480 int snd_seq_client_notify_subscription(int client, int port,
1481 				       struct snd_seq_port_subscribe *info,
1482 				       int evtype)
1483 {
1484 	struct snd_seq_event event;
1485 
1486 	memset(&event, 0, sizeof(event));
1487 	event.type = evtype;
1488 	event.data.connect.dest = info->dest;
1489 	event.data.connect.sender = info->sender;
1490 
1491 	return snd_seq_system_notify(client, port, &event, false);  /* non-atomic */
1492 }
1493 
1494 
1495 /*
1496  * add to port's subscription list IOCTL interface
1497  */
1498 static int snd_seq_ioctl_subscribe_port(struct snd_seq_client *client,
1499 					void *arg)
1500 {
1501 	struct snd_seq_port_subscribe *subs = arg;
1502 	int result = -EINVAL;
1503 	struct snd_seq_client *receiver = NULL, *sender = NULL;
1504 	struct snd_seq_client_port *sport = NULL, *dport = NULL;
1505 
1506 	receiver = snd_seq_client_use_ptr(subs->dest.client);
1507 	if (!receiver)
1508 		goto __end;
1509 	sender = snd_seq_client_use_ptr(subs->sender.client);
1510 	if (!sender)
1511 		goto __end;
1512 	sport = snd_seq_port_use_ptr(sender, subs->sender.port);
1513 	if (!sport)
1514 		goto __end;
1515 	dport = snd_seq_port_use_ptr(receiver, subs->dest.port);
1516 	if (!dport)
1517 		goto __end;
1518 
1519 	result = check_subscription_permission(client, sport, dport, subs);
1520 	if (result < 0)
1521 		goto __end;
1522 
1523 	/* connect them */
1524 	result = snd_seq_port_connect(client, sender, sport, receiver, dport, subs);
1525 	if (! result) /* broadcast announce */
1526 		snd_seq_client_notify_subscription(SNDRV_SEQ_ADDRESS_SUBSCRIBERS, 0,
1527 						   subs, SNDRV_SEQ_EVENT_PORT_SUBSCRIBED);
1528       __end:
1529       	if (sport)
1530 		snd_seq_port_unlock(sport);
1531 	if (dport)
1532 		snd_seq_port_unlock(dport);
1533 	if (sender)
1534 		snd_seq_client_unlock(sender);
1535 	if (receiver)
1536 		snd_seq_client_unlock(receiver);
1537 	return result;
1538 }
1539 
1540 
1541 /*
1542  * remove from port's subscription list
1543  */
1544 static int snd_seq_ioctl_unsubscribe_port(struct snd_seq_client *client,
1545 					  void *arg)
1546 {
1547 	struct snd_seq_port_subscribe *subs = arg;
1548 	int result = -ENXIO;
1549 	struct snd_seq_client *receiver = NULL, *sender = NULL;
1550 	struct snd_seq_client_port *sport = NULL, *dport = NULL;
1551 
1552 	receiver = snd_seq_client_use_ptr(subs->dest.client);
1553 	if (!receiver)
1554 		goto __end;
1555 	sender = snd_seq_client_use_ptr(subs->sender.client);
1556 	if (!sender)
1557 		goto __end;
1558 	sport = snd_seq_port_use_ptr(sender, subs->sender.port);
1559 	if (!sport)
1560 		goto __end;
1561 	dport = snd_seq_port_use_ptr(receiver, subs->dest.port);
1562 	if (!dport)
1563 		goto __end;
1564 
1565 	result = check_subscription_permission(client, sport, dport, subs);
1566 	if (result < 0)
1567 		goto __end;
1568 
1569 	result = snd_seq_port_disconnect(client, sender, sport, receiver, dport, subs);
1570 	if (! result) /* broadcast announce */
1571 		snd_seq_client_notify_subscription(SNDRV_SEQ_ADDRESS_SUBSCRIBERS, 0,
1572 						   subs, SNDRV_SEQ_EVENT_PORT_UNSUBSCRIBED);
1573       __end:
1574       	if (sport)
1575 		snd_seq_port_unlock(sport);
1576 	if (dport)
1577 		snd_seq_port_unlock(dport);
1578 	if (sender)
1579 		snd_seq_client_unlock(sender);
1580 	if (receiver)
1581 		snd_seq_client_unlock(receiver);
1582 	return result;
1583 }
1584 
1585 
1586 /* CREATE_QUEUE ioctl() */
1587 static int snd_seq_ioctl_create_queue(struct snd_seq_client *client, void *arg)
1588 {
1589 	struct snd_seq_queue_info *info = arg;
1590 	struct snd_seq_queue *q;
1591 
1592 	q = snd_seq_queue_alloc(client->number, info->locked, info->flags);
1593 	if (IS_ERR(q))
1594 		return PTR_ERR(q);
1595 
1596 	info->queue = q->queue;
1597 	info->locked = q->locked;
1598 	info->owner = q->owner;
1599 
1600 	/* set queue name */
1601 	if (!info->name[0])
1602 		snprintf(info->name, sizeof(info->name), "Queue-%d", q->queue);
1603 	strscpy(q->name, info->name, sizeof(q->name));
1604 	snd_use_lock_free(&q->use_lock);
1605 
1606 	return 0;
1607 }
1608 
1609 /* DELETE_QUEUE ioctl() */
1610 static int snd_seq_ioctl_delete_queue(struct snd_seq_client *client, void *arg)
1611 {
1612 	struct snd_seq_queue_info *info = arg;
1613 
1614 	return snd_seq_queue_delete(client->number, info->queue);
1615 }
1616 
1617 /* GET_QUEUE_INFO ioctl() */
1618 static int snd_seq_ioctl_get_queue_info(struct snd_seq_client *client,
1619 					void *arg)
1620 {
1621 	struct snd_seq_queue_info *info = arg;
1622 	struct snd_seq_queue *q;
1623 
1624 	q = queueptr(info->queue);
1625 	if (q == NULL)
1626 		return -EINVAL;
1627 
1628 	memset(info, 0, sizeof(*info));
1629 	info->queue = q->queue;
1630 	info->owner = q->owner;
1631 	info->locked = q->locked;
1632 	strscpy(info->name, q->name, sizeof(info->name));
1633 	queuefree(q);
1634 
1635 	return 0;
1636 }
1637 
1638 /* SET_QUEUE_INFO ioctl() */
1639 static int snd_seq_ioctl_set_queue_info(struct snd_seq_client *client,
1640 					void *arg)
1641 {
1642 	struct snd_seq_queue_info *info = arg;
1643 	struct snd_seq_queue *q;
1644 
1645 	if (info->owner != client->number)
1646 		return -EINVAL;
1647 
1648 	/* change owner/locked permission */
1649 	if (snd_seq_queue_check_access(info->queue, client->number)) {
1650 		if (snd_seq_queue_set_owner(info->queue, client->number, info->locked) < 0)
1651 			return -EPERM;
1652 		if (info->locked)
1653 			snd_seq_queue_use(info->queue, client->number, 1);
1654 	} else {
1655 		return -EPERM;
1656 	}
1657 
1658 	q = queueptr(info->queue);
1659 	if (! q)
1660 		return -EINVAL;
1661 	if (q->owner != client->number) {
1662 		queuefree(q);
1663 		return -EPERM;
1664 	}
1665 	strscpy(q->name, info->name, sizeof(q->name));
1666 	queuefree(q);
1667 
1668 	return 0;
1669 }
1670 
1671 /* GET_NAMED_QUEUE ioctl() */
1672 static int snd_seq_ioctl_get_named_queue(struct snd_seq_client *client,
1673 					 void *arg)
1674 {
1675 	struct snd_seq_queue_info *info = arg;
1676 	struct snd_seq_queue *q;
1677 
1678 	q = snd_seq_queue_find_name(info->name);
1679 	if (q == NULL)
1680 		return -EINVAL;
1681 	info->queue = q->queue;
1682 	info->owner = q->owner;
1683 	info->locked = q->locked;
1684 	queuefree(q);
1685 
1686 	return 0;
1687 }
1688 
1689 /* GET_QUEUE_STATUS ioctl() */
1690 static int snd_seq_ioctl_get_queue_status(struct snd_seq_client *client,
1691 					  void *arg)
1692 {
1693 	struct snd_seq_queue_status *status = arg;
1694 	struct snd_seq_queue *queue;
1695 	struct snd_seq_timer *tmr;
1696 
1697 	queue = queueptr(status->queue);
1698 	if (queue == NULL)
1699 		return -EINVAL;
1700 	memset(status, 0, sizeof(*status));
1701 	status->queue = queue->queue;
1702 
1703 	tmr = queue->timer;
1704 	status->events = queue->tickq->cells + queue->timeq->cells;
1705 
1706 	status->time = snd_seq_timer_get_cur_time(tmr, true);
1707 	status->tick = snd_seq_timer_get_cur_tick(tmr);
1708 
1709 	status->running = tmr->running;
1710 
1711 	status->flags = queue->flags;
1712 	queuefree(queue);
1713 
1714 	return 0;
1715 }
1716 
1717 
1718 /* GET_QUEUE_TEMPO ioctl() */
1719 static int snd_seq_ioctl_get_queue_tempo(struct snd_seq_client *client,
1720 					 void *arg)
1721 {
1722 	struct snd_seq_queue_tempo *tempo = arg;
1723 	struct snd_seq_queue *queue;
1724 	struct snd_seq_timer *tmr;
1725 
1726 	queue = queueptr(tempo->queue);
1727 	if (queue == NULL)
1728 		return -EINVAL;
1729 	memset(tempo, 0, sizeof(*tempo));
1730 	tempo->queue = queue->queue;
1731 
1732 	tmr = queue->timer;
1733 
1734 	tempo->tempo = tmr->tempo;
1735 	tempo->ppq = tmr->ppq;
1736 	tempo->skew_value = tmr->skew;
1737 	tempo->skew_base = tmr->skew_base;
1738 	if (client->user_pversion >= SNDRV_PROTOCOL_VERSION(1, 0, 4))
1739 		tempo->tempo_base = tmr->tempo_base;
1740 	queuefree(queue);
1741 
1742 	return 0;
1743 }
1744 
1745 
1746 /* SET_QUEUE_TEMPO ioctl() */
1747 int snd_seq_set_queue_tempo(int client, struct snd_seq_queue_tempo *tempo)
1748 {
1749 	if (!snd_seq_queue_check_access(tempo->queue, client))
1750 		return -EPERM;
1751 	return snd_seq_queue_timer_set_tempo(tempo->queue, client, tempo);
1752 }
1753 EXPORT_SYMBOL(snd_seq_set_queue_tempo);
1754 
1755 static int snd_seq_ioctl_set_queue_tempo(struct snd_seq_client *client,
1756 					 void *arg)
1757 {
1758 	struct snd_seq_queue_tempo *tempo = arg;
1759 	int result;
1760 
1761 	if (client->user_pversion < SNDRV_PROTOCOL_VERSION(1, 0, 4))
1762 		tempo->tempo_base = 0;
1763 	result = snd_seq_set_queue_tempo(client->number, tempo);
1764 	return result < 0 ? result : 0;
1765 }
1766 
1767 
1768 /* GET_QUEUE_TIMER ioctl() */
1769 static int snd_seq_ioctl_get_queue_timer(struct snd_seq_client *client,
1770 					 void *arg)
1771 {
1772 	struct snd_seq_queue_timer *timer = arg;
1773 	struct snd_seq_queue *queue;
1774 	struct snd_seq_timer *tmr;
1775 
1776 	queue = queueptr(timer->queue);
1777 	if (queue == NULL)
1778 		return -EINVAL;
1779 
1780 	mutex_lock(&queue->timer_mutex);
1781 	tmr = queue->timer;
1782 	memset(timer, 0, sizeof(*timer));
1783 	timer->queue = queue->queue;
1784 
1785 	timer->type = tmr->type;
1786 	if (tmr->type == SNDRV_SEQ_TIMER_ALSA) {
1787 		timer->u.alsa.id = tmr->alsa_id;
1788 		timer->u.alsa.resolution = tmr->preferred_resolution;
1789 	}
1790 	mutex_unlock(&queue->timer_mutex);
1791 	queuefree(queue);
1792 
1793 	return 0;
1794 }
1795 
1796 
1797 /* SET_QUEUE_TIMER ioctl() */
1798 static int snd_seq_ioctl_set_queue_timer(struct snd_seq_client *client,
1799 					 void *arg)
1800 {
1801 	struct snd_seq_queue_timer *timer = arg;
1802 	int result = 0;
1803 
1804 	if (timer->type != SNDRV_SEQ_TIMER_ALSA)
1805 		return -EINVAL;
1806 
1807 	if (snd_seq_queue_check_access(timer->queue, client->number)) {
1808 		struct snd_seq_queue *q;
1809 		struct snd_seq_timer *tmr;
1810 
1811 		q = queueptr(timer->queue);
1812 		if (q == NULL)
1813 			return -ENXIO;
1814 		mutex_lock(&q->timer_mutex);
1815 		tmr = q->timer;
1816 		snd_seq_queue_timer_close(timer->queue);
1817 		tmr->type = timer->type;
1818 		if (tmr->type == SNDRV_SEQ_TIMER_ALSA) {
1819 			tmr->alsa_id = timer->u.alsa.id;
1820 			tmr->preferred_resolution = timer->u.alsa.resolution;
1821 		}
1822 		result = snd_seq_queue_timer_open(timer->queue);
1823 		mutex_unlock(&q->timer_mutex);
1824 		queuefree(q);
1825 	} else {
1826 		return -EPERM;
1827 	}
1828 
1829 	return result;
1830 }
1831 
1832 
1833 /* GET_QUEUE_CLIENT ioctl() */
1834 static int snd_seq_ioctl_get_queue_client(struct snd_seq_client *client,
1835 					  void *arg)
1836 {
1837 	struct snd_seq_queue_client *info = arg;
1838 	int used;
1839 
1840 	used = snd_seq_queue_is_used(info->queue, client->number);
1841 	if (used < 0)
1842 		return -EINVAL;
1843 	info->used = used;
1844 	info->client = client->number;
1845 
1846 	return 0;
1847 }
1848 
1849 
1850 /* SET_QUEUE_CLIENT ioctl() */
1851 static int snd_seq_ioctl_set_queue_client(struct snd_seq_client *client,
1852 					  void *arg)
1853 {
1854 	struct snd_seq_queue_client *info = arg;
1855 	int err;
1856 
1857 	if (info->used >= 0) {
1858 		err = snd_seq_queue_use(info->queue, client->number, info->used);
1859 		if (err < 0)
1860 			return err;
1861 	}
1862 
1863 	return snd_seq_ioctl_get_queue_client(client, arg);
1864 }
1865 
1866 
1867 /* GET_CLIENT_POOL ioctl() */
1868 static int snd_seq_ioctl_get_client_pool(struct snd_seq_client *client,
1869 					 void *arg)
1870 {
1871 	struct snd_seq_client_pool *info = arg;
1872 	struct snd_seq_client *cptr;
1873 
1874 	cptr = snd_seq_client_use_ptr(info->client);
1875 	if (cptr == NULL)
1876 		return -ENOENT;
1877 	memset(info, 0, sizeof(*info));
1878 	info->client = cptr->number;
1879 	info->output_pool = cptr->pool->size;
1880 	info->output_room = cptr->pool->room;
1881 	info->output_free = info->output_pool;
1882 	info->output_free = snd_seq_unused_cells(cptr->pool);
1883 	if (cptr->type == USER_CLIENT) {
1884 		info->input_pool = cptr->data.user.fifo_pool_size;
1885 		info->input_free = info->input_pool;
1886 		info->input_free = snd_seq_fifo_unused_cells(cptr->data.user.fifo);
1887 	} else {
1888 		info->input_pool = 0;
1889 		info->input_free = 0;
1890 	}
1891 	snd_seq_client_unlock(cptr);
1892 
1893 	return 0;
1894 }
1895 
1896 /* SET_CLIENT_POOL ioctl() */
1897 static int snd_seq_ioctl_set_client_pool(struct snd_seq_client *client,
1898 					 void *arg)
1899 {
1900 	struct snd_seq_client_pool *info = arg;
1901 	int rc;
1902 
1903 	if (client->number != info->client)
1904 		return -EINVAL; /* can't change other clients */
1905 
1906 	if (info->output_pool >= 1 && info->output_pool <= SNDRV_SEQ_MAX_EVENTS &&
1907 	    (! snd_seq_write_pool_allocated(client) ||
1908 	     info->output_pool != client->pool->size)) {
1909 		if (snd_seq_write_pool_allocated(client)) {
1910 			/* is the pool in use? */
1911 			if (atomic_read(&client->pool->counter))
1912 				return -EBUSY;
1913 			/* remove all existing cells */
1914 			snd_seq_pool_mark_closing(client->pool);
1915 			snd_seq_pool_done(client->pool);
1916 		}
1917 		client->pool->size = info->output_pool;
1918 		rc = snd_seq_pool_init(client->pool);
1919 		if (rc < 0)
1920 			return rc;
1921 	}
1922 	if (client->type == USER_CLIENT && client->data.user.fifo != NULL &&
1923 	    info->input_pool >= 1 &&
1924 	    info->input_pool <= SNDRV_SEQ_MAX_CLIENT_EVENTS &&
1925 	    info->input_pool != client->data.user.fifo_pool_size) {
1926 		/* change pool size */
1927 		rc = snd_seq_fifo_resize(client->data.user.fifo, info->input_pool);
1928 		if (rc < 0)
1929 			return rc;
1930 		client->data.user.fifo_pool_size = info->input_pool;
1931 	}
1932 	if (info->output_room >= 1 &&
1933 	    info->output_room <= client->pool->size) {
1934 		client->pool->room  = info->output_room;
1935 	}
1936 
1937 	return snd_seq_ioctl_get_client_pool(client, arg);
1938 }
1939 
1940 
1941 /* REMOVE_EVENTS ioctl() */
1942 static int snd_seq_ioctl_remove_events(struct snd_seq_client *client,
1943 				       void *arg)
1944 {
1945 	struct snd_seq_remove_events *info = arg;
1946 
1947 	/*
1948 	 * Input mostly not implemented XXX.
1949 	 */
1950 	if (info->remove_mode & SNDRV_SEQ_REMOVE_INPUT) {
1951 		/*
1952 		 * No restrictions so for a user client we can clear
1953 		 * the whole fifo
1954 		 */
1955 		if (client->type == USER_CLIENT && client->data.user.fifo)
1956 			snd_seq_fifo_clear(client->data.user.fifo);
1957 	}
1958 
1959 	if (info->remove_mode & SNDRV_SEQ_REMOVE_OUTPUT)
1960 		snd_seq_queue_remove_cells(client->number, info);
1961 
1962 	return 0;
1963 }
1964 
1965 
1966 /*
1967  * get subscription info
1968  */
1969 static int snd_seq_ioctl_get_subscription(struct snd_seq_client *client,
1970 					  void *arg)
1971 {
1972 	struct snd_seq_port_subscribe *subs = arg;
1973 	int result;
1974 	struct snd_seq_client *sender = NULL;
1975 	struct snd_seq_client_port *sport = NULL;
1976 
1977 	result = -EINVAL;
1978 	sender = snd_seq_client_use_ptr(subs->sender.client);
1979 	if (!sender)
1980 		goto __end;
1981 	sport = snd_seq_port_use_ptr(sender, subs->sender.port);
1982 	if (!sport)
1983 		goto __end;
1984 	result = snd_seq_port_get_subscription(&sport->c_src, &subs->dest,
1985 					       subs);
1986       __end:
1987       	if (sport)
1988 		snd_seq_port_unlock(sport);
1989 	if (sender)
1990 		snd_seq_client_unlock(sender);
1991 
1992 	return result;
1993 }
1994 
1995 
1996 /*
1997  * get subscription info - check only its presence
1998  */
1999 static int snd_seq_ioctl_query_subs(struct snd_seq_client *client, void *arg)
2000 {
2001 	struct snd_seq_query_subs *subs = arg;
2002 	int result = -ENXIO;
2003 	struct snd_seq_client *cptr = NULL;
2004 	struct snd_seq_client_port *port = NULL;
2005 	struct snd_seq_port_subs_info *group;
2006 	struct list_head *p;
2007 	int i;
2008 
2009 	cptr = snd_seq_client_use_ptr(subs->root.client);
2010 	if (!cptr)
2011 		goto __end;
2012 	port = snd_seq_port_use_ptr(cptr, subs->root.port);
2013 	if (!port)
2014 		goto __end;
2015 
2016 	switch (subs->type) {
2017 	case SNDRV_SEQ_QUERY_SUBS_READ:
2018 		group = &port->c_src;
2019 		break;
2020 	case SNDRV_SEQ_QUERY_SUBS_WRITE:
2021 		group = &port->c_dest;
2022 		break;
2023 	default:
2024 		goto __end;
2025 	}
2026 
2027 	down_read(&group->list_mutex);
2028 	/* search for the subscriber */
2029 	subs->num_subs = group->count;
2030 	i = 0;
2031 	result = -ENOENT;
2032 	list_for_each(p, &group->list_head) {
2033 		if (i++ == subs->index) {
2034 			/* found! */
2035 			struct snd_seq_subscribers *s;
2036 			if (subs->type == SNDRV_SEQ_QUERY_SUBS_READ) {
2037 				s = list_entry(p, struct snd_seq_subscribers, src_list);
2038 				subs->addr = s->info.dest;
2039 			} else {
2040 				s = list_entry(p, struct snd_seq_subscribers, dest_list);
2041 				subs->addr = s->info.sender;
2042 			}
2043 			subs->flags = s->info.flags;
2044 			subs->queue = s->info.queue;
2045 			result = 0;
2046 			break;
2047 		}
2048 	}
2049 	up_read(&group->list_mutex);
2050 
2051       __end:
2052    	if (port)
2053 		snd_seq_port_unlock(port);
2054 	if (cptr)
2055 		snd_seq_client_unlock(cptr);
2056 
2057 	return result;
2058 }
2059 
2060 
2061 /*
2062  * query next client
2063  */
2064 static int snd_seq_ioctl_query_next_client(struct snd_seq_client *client,
2065 					   void *arg)
2066 {
2067 	struct snd_seq_client_info *info = arg;
2068 	struct snd_seq_client *cptr = NULL;
2069 
2070 	/* search for next client */
2071 	if (info->client < INT_MAX)
2072 		info->client++;
2073 	if (info->client < 0)
2074 		info->client = 0;
2075 	for (; info->client < SNDRV_SEQ_MAX_CLIENTS; info->client++) {
2076 		cptr = snd_seq_client_use_ptr(info->client);
2077 		if (cptr)
2078 			break; /* found */
2079 	}
2080 	if (cptr == NULL)
2081 		return -ENOENT;
2082 
2083 	get_client_info(cptr, info);
2084 	snd_seq_client_unlock(cptr);
2085 
2086 	return 0;
2087 }
2088 
2089 /*
2090  * query next port
2091  */
2092 static int snd_seq_ioctl_query_next_port(struct snd_seq_client *client,
2093 					 void *arg)
2094 {
2095 	struct snd_seq_port_info *info = arg;
2096 	struct snd_seq_client *cptr;
2097 	struct snd_seq_client_port *port = NULL;
2098 
2099 	cptr = snd_seq_client_use_ptr(info->addr.client);
2100 	if (cptr == NULL)
2101 		return -ENXIO;
2102 
2103 	/* search for next port */
2104 	info->addr.port++;
2105 	port = snd_seq_port_query_nearest(cptr, info);
2106 	if (port == NULL) {
2107 		snd_seq_client_unlock(cptr);
2108 		return -ENOENT;
2109 	}
2110 
2111 	/* get port info */
2112 	info->addr = port->addr;
2113 	snd_seq_get_port_info(port, info);
2114 	snd_seq_port_unlock(port);
2115 	snd_seq_client_unlock(cptr);
2116 
2117 	return 0;
2118 }
2119 
2120 #if IS_ENABLED(CONFIG_SND_SEQ_UMP)
2121 #define NUM_UMP_INFOS (SNDRV_UMP_MAX_BLOCKS + 1)
2122 
2123 static void free_ump_info(struct snd_seq_client *client)
2124 {
2125 	int i;
2126 
2127 	if (!client->ump_info)
2128 		return;
2129 	for (i = 0; i < NUM_UMP_INFOS; i++)
2130 		kfree(client->ump_info[i]);
2131 	kfree(client->ump_info);
2132 	client->ump_info = NULL;
2133 }
2134 
2135 static void terminate_ump_info_strings(void *p, int type)
2136 {
2137 	if (type == SNDRV_SEQ_CLIENT_UMP_INFO_ENDPOINT) {
2138 		struct snd_ump_endpoint_info *ep = p;
2139 		ep->name[sizeof(ep->name) - 1] = 0;
2140 	} else {
2141 		struct snd_ump_block_info *bp = p;
2142 		bp->name[sizeof(bp->name) - 1] = 0;
2143 	}
2144 }
2145 
2146 #ifdef CONFIG_SND_PROC_FS
2147 static void dump_ump_info(struct snd_info_buffer *buffer,
2148 			  struct snd_seq_client *client)
2149 {
2150 	struct snd_ump_endpoint_info *ep;
2151 	struct snd_ump_block_info *bp;
2152 	int i;
2153 
2154 	if (!client->ump_info)
2155 		return;
2156 	ep = client->ump_info[SNDRV_SEQ_CLIENT_UMP_INFO_ENDPOINT];
2157 	if (ep && *ep->name)
2158 		snd_iprintf(buffer, "  UMP Endpoint: \"%s\"\n", ep->name);
2159 	for (i = 0; i < SNDRV_UMP_MAX_BLOCKS; i++) {
2160 		bp = client->ump_info[i + 1];
2161 		if (bp && *bp->name) {
2162 			snd_iprintf(buffer, "  UMP Block %d: \"%s\" [%s]\n",
2163 				    i, bp->name,
2164 				    bp->active ? "Active" : "Inactive");
2165 			snd_iprintf(buffer, "    Groups: %d-%d\n",
2166 				    bp->first_group + 1,
2167 				    bp->first_group + bp->num_groups);
2168 		}
2169 	}
2170 }
2171 #endif
2172 
2173 /* UMP-specific ioctls -- called directly without data copy */
2174 static int snd_seq_ioctl_client_ump_info(struct snd_seq_client *caller,
2175 					 unsigned int cmd,
2176 					 unsigned long arg)
2177 {
2178 	struct snd_seq_client_ump_info __user *argp =
2179 		(struct snd_seq_client_ump_info __user *)arg;
2180 	struct snd_seq_client *cptr;
2181 	int client, type, err = 0;
2182 	size_t size;
2183 	void *p;
2184 
2185 	if (get_user(client, &argp->client) || get_user(type, &argp->type))
2186 		return -EFAULT;
2187 	if (cmd == SNDRV_SEQ_IOCTL_SET_CLIENT_UMP_INFO &&
2188 	    caller->number != client)
2189 		return -EPERM;
2190 	if (type < 0 || type >= NUM_UMP_INFOS)
2191 		return -EINVAL;
2192 	if (type == SNDRV_SEQ_CLIENT_UMP_INFO_ENDPOINT)
2193 		size = sizeof(struct snd_ump_endpoint_info);
2194 	else
2195 		size = sizeof(struct snd_ump_block_info);
2196 	cptr = snd_seq_client_use_ptr(client);
2197 	if (!cptr)
2198 		return -ENOENT;
2199 
2200 	mutex_lock(&cptr->ioctl_mutex);
2201 	if (!cptr->midi_version) {
2202 		err = -EBADFD;
2203 		goto error;
2204 	}
2205 
2206 	if (cmd == SNDRV_SEQ_IOCTL_GET_CLIENT_UMP_INFO) {
2207 		if (!cptr->ump_info)
2208 			p = NULL;
2209 		else
2210 			p = cptr->ump_info[type];
2211 		if (!p) {
2212 			err = -ENODEV;
2213 			goto error;
2214 		}
2215 		if (copy_to_user(argp->info, p, size)) {
2216 			err = -EFAULT;
2217 			goto error;
2218 		}
2219 	} else {
2220 		if (cptr->type != USER_CLIENT) {
2221 			err = -EBADFD;
2222 			goto error;
2223 		}
2224 		if (!cptr->ump_info) {
2225 			cptr->ump_info = kcalloc(NUM_UMP_INFOS,
2226 						 sizeof(void *), GFP_KERNEL);
2227 			if (!cptr->ump_info) {
2228 				err = -ENOMEM;
2229 				goto error;
2230 			}
2231 		}
2232 		p = memdup_user(argp->info, size);
2233 		if (IS_ERR(p)) {
2234 			err = PTR_ERR(p);
2235 			goto error;
2236 		}
2237 		kfree(cptr->ump_info[type]);
2238 		terminate_ump_info_strings(p, type);
2239 		cptr->ump_info[type] = p;
2240 	}
2241 
2242  error:
2243 	mutex_unlock(&cptr->ioctl_mutex);
2244 	snd_seq_client_unlock(cptr);
2245 	if (!err && cmd == SNDRV_SEQ_IOCTL_SET_CLIENT_UMP_INFO) {
2246 		if (type == SNDRV_SEQ_CLIENT_UMP_INFO_ENDPOINT)
2247 			snd_seq_system_ump_notify(client, 0,
2248 						  SNDRV_SEQ_EVENT_UMP_EP_CHANGE,
2249 						  false);
2250 		else
2251 			snd_seq_system_ump_notify(client, type - 1,
2252 						  SNDRV_SEQ_EVENT_UMP_BLOCK_CHANGE,
2253 						  false);
2254 	}
2255 	return err;
2256 }
2257 #endif
2258 
2259 /* -------------------------------------------------------- */
2260 
2261 static const struct ioctl_handler {
2262 	unsigned int cmd;
2263 	int (*func)(struct snd_seq_client *client, void *arg);
2264 } ioctl_handlers[] = {
2265 	{ SNDRV_SEQ_IOCTL_PVERSION, snd_seq_ioctl_pversion },
2266 	{ SNDRV_SEQ_IOCTL_USER_PVERSION, snd_seq_ioctl_user_pversion },
2267 	{ SNDRV_SEQ_IOCTL_CLIENT_ID, snd_seq_ioctl_client_id },
2268 	{ SNDRV_SEQ_IOCTL_SYSTEM_INFO, snd_seq_ioctl_system_info },
2269 	{ SNDRV_SEQ_IOCTL_RUNNING_MODE, snd_seq_ioctl_running_mode },
2270 	{ SNDRV_SEQ_IOCTL_GET_CLIENT_INFO, snd_seq_ioctl_get_client_info },
2271 	{ SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, snd_seq_ioctl_set_client_info },
2272 	{ SNDRV_SEQ_IOCTL_CREATE_PORT, snd_seq_ioctl_create_port },
2273 	{ SNDRV_SEQ_IOCTL_DELETE_PORT, snd_seq_ioctl_delete_port },
2274 	{ SNDRV_SEQ_IOCTL_GET_PORT_INFO, snd_seq_ioctl_get_port_info },
2275 	{ SNDRV_SEQ_IOCTL_SET_PORT_INFO, snd_seq_ioctl_set_port_info },
2276 	{ SNDRV_SEQ_IOCTL_SUBSCRIBE_PORT, snd_seq_ioctl_subscribe_port },
2277 	{ SNDRV_SEQ_IOCTL_UNSUBSCRIBE_PORT, snd_seq_ioctl_unsubscribe_port },
2278 	{ SNDRV_SEQ_IOCTL_CREATE_QUEUE, snd_seq_ioctl_create_queue },
2279 	{ SNDRV_SEQ_IOCTL_DELETE_QUEUE, snd_seq_ioctl_delete_queue },
2280 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_INFO, snd_seq_ioctl_get_queue_info },
2281 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_INFO, snd_seq_ioctl_set_queue_info },
2282 	{ SNDRV_SEQ_IOCTL_GET_NAMED_QUEUE, snd_seq_ioctl_get_named_queue },
2283 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_STATUS, snd_seq_ioctl_get_queue_status },
2284 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_TEMPO, snd_seq_ioctl_get_queue_tempo },
2285 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_TEMPO, snd_seq_ioctl_set_queue_tempo },
2286 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_TIMER, snd_seq_ioctl_get_queue_timer },
2287 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_TIMER, snd_seq_ioctl_set_queue_timer },
2288 	{ SNDRV_SEQ_IOCTL_GET_QUEUE_CLIENT, snd_seq_ioctl_get_queue_client },
2289 	{ SNDRV_SEQ_IOCTL_SET_QUEUE_CLIENT, snd_seq_ioctl_set_queue_client },
2290 	{ SNDRV_SEQ_IOCTL_GET_CLIENT_POOL, snd_seq_ioctl_get_client_pool },
2291 	{ SNDRV_SEQ_IOCTL_SET_CLIENT_POOL, snd_seq_ioctl_set_client_pool },
2292 	{ SNDRV_SEQ_IOCTL_GET_SUBSCRIPTION, snd_seq_ioctl_get_subscription },
2293 	{ SNDRV_SEQ_IOCTL_QUERY_NEXT_CLIENT, snd_seq_ioctl_query_next_client },
2294 	{ SNDRV_SEQ_IOCTL_QUERY_NEXT_PORT, snd_seq_ioctl_query_next_port },
2295 	{ SNDRV_SEQ_IOCTL_REMOVE_EVENTS, snd_seq_ioctl_remove_events },
2296 	{ SNDRV_SEQ_IOCTL_QUERY_SUBS, snd_seq_ioctl_query_subs },
2297 	{ 0, NULL },
2298 };
2299 
2300 static long snd_seq_ioctl(struct file *file, unsigned int cmd,
2301 			  unsigned long arg)
2302 {
2303 	struct snd_seq_client *client = file->private_data;
2304 	/* To use kernel stack for ioctl data. */
2305 	union {
2306 		int pversion;
2307 		int client_id;
2308 		struct snd_seq_system_info	system_info;
2309 		struct snd_seq_running_info	running_info;
2310 		struct snd_seq_client_info	client_info;
2311 		struct snd_seq_port_info	port_info;
2312 		struct snd_seq_port_subscribe	port_subscribe;
2313 		struct snd_seq_queue_info	queue_info;
2314 		struct snd_seq_queue_status	queue_status;
2315 		struct snd_seq_queue_tempo	tempo;
2316 		struct snd_seq_queue_timer	queue_timer;
2317 		struct snd_seq_queue_client	queue_client;
2318 		struct snd_seq_client_pool	client_pool;
2319 		struct snd_seq_remove_events	remove_events;
2320 		struct snd_seq_query_subs	query_subs;
2321 	} buf;
2322 	const struct ioctl_handler *handler;
2323 	unsigned long size;
2324 	int err;
2325 
2326 	if (snd_BUG_ON(!client))
2327 		return -ENXIO;
2328 
2329 #if IS_ENABLED(CONFIG_SND_SEQ_UMP)
2330 	/* exception - handling large data */
2331 	switch (cmd) {
2332 	case SNDRV_SEQ_IOCTL_GET_CLIENT_UMP_INFO:
2333 	case SNDRV_SEQ_IOCTL_SET_CLIENT_UMP_INFO:
2334 		return snd_seq_ioctl_client_ump_info(client, cmd, arg);
2335 	}
2336 #endif
2337 
2338 	for (handler = ioctl_handlers; handler->cmd > 0; ++handler) {
2339 		if (handler->cmd == cmd)
2340 			break;
2341 	}
2342 	if (handler->cmd == 0)
2343 		return -ENOTTY;
2344 
2345 	memset(&buf, 0, sizeof(buf));
2346 
2347 	/*
2348 	 * All of ioctl commands for ALSA sequencer get an argument of size
2349 	 * within 13 bits. We can safely pick up the size from the command.
2350 	 */
2351 	size = _IOC_SIZE(handler->cmd);
2352 	if (handler->cmd & IOC_IN) {
2353 		if (copy_from_user(&buf, (const void __user *)arg, size))
2354 			return -EFAULT;
2355 	}
2356 
2357 	mutex_lock(&client->ioctl_mutex);
2358 	err = handler->func(client, &buf);
2359 	mutex_unlock(&client->ioctl_mutex);
2360 	if (err >= 0) {
2361 		/* Some commands includes a bug in 'dir' field. */
2362 		if (handler->cmd == SNDRV_SEQ_IOCTL_SET_QUEUE_CLIENT ||
2363 		    handler->cmd == SNDRV_SEQ_IOCTL_SET_CLIENT_POOL ||
2364 		    (handler->cmd & IOC_OUT))
2365 			if (copy_to_user((void __user *)arg, &buf, size))
2366 				return -EFAULT;
2367 	}
2368 
2369 	return err;
2370 }
2371 
2372 #ifdef CONFIG_COMPAT
2373 #include "seq_compat.c"
2374 #else
2375 #define snd_seq_ioctl_compat	NULL
2376 #endif
2377 
2378 /* -------------------------------------------------------- */
2379 
2380 
2381 /* exported to kernel modules */
2382 int snd_seq_create_kernel_client(struct snd_card *card, int client_index,
2383 				 const char *name_fmt, ...)
2384 {
2385 	struct snd_seq_client *client;
2386 	va_list args;
2387 
2388 	if (snd_BUG_ON(in_interrupt()))
2389 		return -EBUSY;
2390 
2391 	if (card && client_index >= SNDRV_SEQ_CLIENTS_PER_CARD)
2392 		return -EINVAL;
2393 	if (card == NULL && client_index >= SNDRV_SEQ_GLOBAL_CLIENTS)
2394 		return -EINVAL;
2395 
2396 	mutex_lock(&register_mutex);
2397 
2398 	if (card) {
2399 		client_index += SNDRV_SEQ_GLOBAL_CLIENTS
2400 			+ card->number * SNDRV_SEQ_CLIENTS_PER_CARD;
2401 		if (client_index >= SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN)
2402 			client_index = -1;
2403 	}
2404 
2405 	/* empty write queue as default */
2406 	client = seq_create_client1(client_index, 0);
2407 	if (client == NULL) {
2408 		mutex_unlock(&register_mutex);
2409 		return -EBUSY;	/* failure code */
2410 	}
2411 	usage_alloc(&client_usage, 1);
2412 
2413 	client->accept_input = 1;
2414 	client->accept_output = 1;
2415 	client->data.kernel.card = card;
2416 	client->user_pversion = SNDRV_SEQ_VERSION;
2417 
2418 	va_start(args, name_fmt);
2419 	vsnprintf(client->name, sizeof(client->name), name_fmt, args);
2420 	va_end(args);
2421 
2422 	client->type = KERNEL_CLIENT;
2423 	mutex_unlock(&register_mutex);
2424 
2425 	/* make others aware this new client */
2426 	snd_seq_system_client_ev_client_start(client->number);
2427 
2428 	/* return client number to caller */
2429 	return client->number;
2430 }
2431 EXPORT_SYMBOL(snd_seq_create_kernel_client);
2432 
2433 /* exported to kernel modules */
2434 int snd_seq_delete_kernel_client(int client)
2435 {
2436 	struct snd_seq_client *ptr;
2437 
2438 	if (snd_BUG_ON(in_interrupt()))
2439 		return -EBUSY;
2440 
2441 	ptr = clientptr(client);
2442 	if (ptr == NULL)
2443 		return -EINVAL;
2444 
2445 	seq_free_client(ptr);
2446 	kfree(ptr);
2447 	return 0;
2448 }
2449 EXPORT_SYMBOL(snd_seq_delete_kernel_client);
2450 
2451 /*
2452  * exported, called by kernel clients to enqueue events (w/o blocking)
2453  *
2454  * RETURN VALUE: zero if succeed, negative if error
2455  */
2456 int snd_seq_kernel_client_enqueue(int client, struct snd_seq_event *ev,
2457 				  struct file *file, bool blocking)
2458 {
2459 	struct snd_seq_client *cptr;
2460 	int result;
2461 
2462 	if (snd_BUG_ON(!ev))
2463 		return -EINVAL;
2464 
2465 	if (!snd_seq_ev_is_ump(ev)) {
2466 		if (ev->type == SNDRV_SEQ_EVENT_NONE)
2467 			return 0; /* ignore this */
2468 		if (ev->type == SNDRV_SEQ_EVENT_KERNEL_ERROR)
2469 			return -EINVAL; /* quoted events can't be enqueued */
2470 	}
2471 
2472 	/* fill in client number */
2473 	ev->source.client = client;
2474 
2475 	if (check_event_type_and_length(ev))
2476 		return -EINVAL;
2477 
2478 	cptr = snd_seq_client_use_ptr(client);
2479 	if (cptr == NULL)
2480 		return -EINVAL;
2481 
2482 	if (!cptr->accept_output) {
2483 		result = -EPERM;
2484 	} else { /* send it */
2485 		mutex_lock(&cptr->ioctl_mutex);
2486 		result = snd_seq_client_enqueue_event(cptr, ev, file, blocking,
2487 						      false, 0,
2488 						      &cptr->ioctl_mutex);
2489 		mutex_unlock(&cptr->ioctl_mutex);
2490 	}
2491 
2492 	snd_seq_client_unlock(cptr);
2493 	return result;
2494 }
2495 EXPORT_SYMBOL(snd_seq_kernel_client_enqueue);
2496 
2497 /*
2498  * exported, called by kernel clients to dispatch events directly to other
2499  * clients, bypassing the queues.  Event time-stamp will be updated.
2500  *
2501  * RETURN VALUE: negative = delivery failed,
2502  *		 zero, or positive: the number of delivered events
2503  */
2504 int snd_seq_kernel_client_dispatch(int client, struct snd_seq_event * ev,
2505 				   int atomic, int hop)
2506 {
2507 	struct snd_seq_client *cptr;
2508 	int result;
2509 
2510 	if (snd_BUG_ON(!ev))
2511 		return -EINVAL;
2512 
2513 	/* fill in client number */
2514 	ev->queue = SNDRV_SEQ_QUEUE_DIRECT;
2515 	ev->source.client = client;
2516 
2517 	if (check_event_type_and_length(ev))
2518 		return -EINVAL;
2519 
2520 	cptr = snd_seq_client_use_ptr(client);
2521 	if (cptr == NULL)
2522 		return -EINVAL;
2523 
2524 	if (!cptr->accept_output)
2525 		result = -EPERM;
2526 	else
2527 		result = snd_seq_deliver_event(cptr, ev, atomic, hop);
2528 
2529 	snd_seq_client_unlock(cptr);
2530 	return result;
2531 }
2532 EXPORT_SYMBOL(snd_seq_kernel_client_dispatch);
2533 
2534 /**
2535  * snd_seq_kernel_client_ctl - operate a command for a client with data in
2536  *			       kernel space.
2537  * @clientid:	A numerical ID for a client.
2538  * @cmd:	An ioctl(2) command for ALSA sequencer operation.
2539  * @arg:	A pointer to data in kernel space.
2540  *
2541  * Against its name, both kernel/application client can be handled by this
2542  * kernel API. A pointer of 'arg' argument should be in kernel space.
2543  *
2544  * Return: 0 at success. Negative error code at failure.
2545  */
2546 int snd_seq_kernel_client_ctl(int clientid, unsigned int cmd, void *arg)
2547 {
2548 	const struct ioctl_handler *handler;
2549 	struct snd_seq_client *client;
2550 
2551 	client = clientptr(clientid);
2552 	if (client == NULL)
2553 		return -ENXIO;
2554 
2555 	for (handler = ioctl_handlers; handler->cmd > 0; ++handler) {
2556 		if (handler->cmd == cmd)
2557 			return handler->func(client, arg);
2558 	}
2559 
2560 	pr_debug("ALSA: seq unknown ioctl() 0x%x (type='%c', number=0x%02x)\n",
2561 		 cmd, _IOC_TYPE(cmd), _IOC_NR(cmd));
2562 	return -ENOTTY;
2563 }
2564 EXPORT_SYMBOL(snd_seq_kernel_client_ctl);
2565 
2566 /* exported (for OSS emulator) */
2567 int snd_seq_kernel_client_write_poll(int clientid, struct file *file, poll_table *wait)
2568 {
2569 	struct snd_seq_client *client;
2570 
2571 	client = clientptr(clientid);
2572 	if (client == NULL)
2573 		return -ENXIO;
2574 
2575 	if (! snd_seq_write_pool_allocated(client))
2576 		return 1;
2577 	if (snd_seq_pool_poll_wait(client->pool, file, wait))
2578 		return 1;
2579 	return 0;
2580 }
2581 EXPORT_SYMBOL(snd_seq_kernel_client_write_poll);
2582 
2583 /* get a sequencer client object; for internal use from a kernel client */
2584 struct snd_seq_client *snd_seq_kernel_client_get(int id)
2585 {
2586 	return snd_seq_client_use_ptr(id);
2587 }
2588 EXPORT_SYMBOL_GPL(snd_seq_kernel_client_get);
2589 
2590 /* put a sequencer client object; for internal use from a kernel client */
2591 void snd_seq_kernel_client_put(struct snd_seq_client *cptr)
2592 {
2593 	if (cptr)
2594 		snd_seq_client_unlock(cptr);
2595 }
2596 EXPORT_SYMBOL_GPL(snd_seq_kernel_client_put);
2597 
2598 /*---------------------------------------------------------------------------*/
2599 
2600 #ifdef CONFIG_SND_PROC_FS
2601 /*
2602  *  /proc interface
2603  */
2604 static void snd_seq_info_dump_subscribers(struct snd_info_buffer *buffer,
2605 					  struct snd_seq_port_subs_info *group,
2606 					  int is_src, char *msg)
2607 {
2608 	struct list_head *p;
2609 	struct snd_seq_subscribers *s;
2610 	int count = 0;
2611 
2612 	down_read(&group->list_mutex);
2613 	if (list_empty(&group->list_head)) {
2614 		up_read(&group->list_mutex);
2615 		return;
2616 	}
2617 	snd_iprintf(buffer, msg);
2618 	list_for_each(p, &group->list_head) {
2619 		if (is_src)
2620 			s = list_entry(p, struct snd_seq_subscribers, src_list);
2621 		else
2622 			s = list_entry(p, struct snd_seq_subscribers, dest_list);
2623 		if (count++)
2624 			snd_iprintf(buffer, ", ");
2625 		snd_iprintf(buffer, "%d:%d",
2626 			    is_src ? s->info.dest.client : s->info.sender.client,
2627 			    is_src ? s->info.dest.port : s->info.sender.port);
2628 		if (s->info.flags & SNDRV_SEQ_PORT_SUBS_TIMESTAMP)
2629 			snd_iprintf(buffer, "[%c:%d]", ((s->info.flags & SNDRV_SEQ_PORT_SUBS_TIME_REAL) ? 'r' : 't'), s->info.queue);
2630 		if (group->exclusive)
2631 			snd_iprintf(buffer, "[ex]");
2632 	}
2633 	up_read(&group->list_mutex);
2634 	snd_iprintf(buffer, "\n");
2635 }
2636 
2637 #define FLAG_PERM_RD(perm) ((perm) & SNDRV_SEQ_PORT_CAP_READ ? ((perm) & SNDRV_SEQ_PORT_CAP_SUBS_READ ? 'R' : 'r') : '-')
2638 #define FLAG_PERM_WR(perm) ((perm) & SNDRV_SEQ_PORT_CAP_WRITE ? ((perm) & SNDRV_SEQ_PORT_CAP_SUBS_WRITE ? 'W' : 'w') : '-')
2639 #define FLAG_PERM_EX(perm) ((perm) & SNDRV_SEQ_PORT_CAP_NO_EXPORT ? '-' : 'e')
2640 
2641 #define FLAG_PERM_DUPLEX(perm) ((perm) & SNDRV_SEQ_PORT_CAP_DUPLEX ? 'X' : '-')
2642 
2643 static const char *port_direction_name(unsigned char dir)
2644 {
2645 	static const char *names[4] = {
2646 		"-", "In", "Out", "In/Out"
2647 	};
2648 
2649 	if (dir > SNDRV_SEQ_PORT_DIR_BIDIRECTION)
2650 		return "Invalid";
2651 	return names[dir];
2652 }
2653 
2654 static void snd_seq_info_dump_ports(struct snd_info_buffer *buffer,
2655 				    struct snd_seq_client *client)
2656 {
2657 	struct snd_seq_client_port *p;
2658 
2659 	mutex_lock(&client->ports_mutex);
2660 	list_for_each_entry(p, &client->ports_list_head, list) {
2661 		if (p->capability & SNDRV_SEQ_PORT_CAP_INACTIVE)
2662 			continue;
2663 		snd_iprintf(buffer, "  Port %3d : \"%s\" (%c%c%c%c) [%s]",
2664 			    p->addr.port, p->name,
2665 			    FLAG_PERM_RD(p->capability),
2666 			    FLAG_PERM_WR(p->capability),
2667 			    FLAG_PERM_EX(p->capability),
2668 			    FLAG_PERM_DUPLEX(p->capability),
2669 			    port_direction_name(p->direction));
2670 #if IS_ENABLED(CONFIG_SND_SEQ_UMP)
2671 		if (snd_seq_client_is_midi2(client) && p->is_midi1)
2672 			snd_iprintf(buffer, " [MIDI1]");
2673 #endif
2674 		snd_iprintf(buffer, "\n");
2675 		snd_seq_info_dump_subscribers(buffer, &p->c_src, 1, "    Connecting To: ");
2676 		snd_seq_info_dump_subscribers(buffer, &p->c_dest, 0, "    Connected From: ");
2677 	}
2678 	mutex_unlock(&client->ports_mutex);
2679 }
2680 
2681 static const char *midi_version_string(unsigned int version)
2682 {
2683 	switch (version) {
2684 	case SNDRV_SEQ_CLIENT_LEGACY_MIDI:
2685 		return "Legacy";
2686 	case SNDRV_SEQ_CLIENT_UMP_MIDI_1_0:
2687 		return "UMP MIDI1";
2688 	case SNDRV_SEQ_CLIENT_UMP_MIDI_2_0:
2689 		return "UMP MIDI2";
2690 	default:
2691 		return "Unknown";
2692 	}
2693 }
2694 
2695 /* exported to seq_info.c */
2696 void snd_seq_info_clients_read(struct snd_info_entry *entry,
2697 			       struct snd_info_buffer *buffer)
2698 {
2699 	int c;
2700 	struct snd_seq_client *client;
2701 
2702 	snd_iprintf(buffer, "Client info\n");
2703 	snd_iprintf(buffer, "  cur  clients : %d\n", client_usage.cur);
2704 	snd_iprintf(buffer, "  peak clients : %d\n", client_usage.peak);
2705 	snd_iprintf(buffer, "  max  clients : %d\n", SNDRV_SEQ_MAX_CLIENTS);
2706 	snd_iprintf(buffer, "\n");
2707 
2708 	/* list the client table */
2709 	for (c = 0; c < SNDRV_SEQ_MAX_CLIENTS; c++) {
2710 		client = snd_seq_client_use_ptr(c);
2711 		if (client == NULL)
2712 			continue;
2713 		if (client->type == NO_CLIENT) {
2714 			snd_seq_client_unlock(client);
2715 			continue;
2716 		}
2717 
2718 		snd_iprintf(buffer, "Client %3d : \"%s\" [%s %s]\n",
2719 			    c, client->name,
2720 			    client->type == USER_CLIENT ? "User" : "Kernel",
2721 			    midi_version_string(client->midi_version));
2722 #if IS_ENABLED(CONFIG_SND_SEQ_UMP)
2723 		dump_ump_info(buffer, client);
2724 #endif
2725 		snd_seq_info_dump_ports(buffer, client);
2726 		if (snd_seq_write_pool_allocated(client)) {
2727 			snd_iprintf(buffer, "  Output pool :\n");
2728 			snd_seq_info_pool(buffer, client->pool, "    ");
2729 		}
2730 		if (client->type == USER_CLIENT && client->data.user.fifo &&
2731 		    client->data.user.fifo->pool) {
2732 			snd_iprintf(buffer, "  Input pool :\n");
2733 			snd_seq_info_pool(buffer, client->data.user.fifo->pool, "    ");
2734 		}
2735 		snd_seq_client_unlock(client);
2736 	}
2737 }
2738 #endif /* CONFIG_SND_PROC_FS */
2739 
2740 /*---------------------------------------------------------------------------*/
2741 
2742 
2743 /*
2744  *  REGISTRATION PART
2745  */
2746 
2747 static const struct file_operations snd_seq_f_ops =
2748 {
2749 	.owner =	THIS_MODULE,
2750 	.read =		snd_seq_read,
2751 	.write =	snd_seq_write,
2752 	.open =		snd_seq_open,
2753 	.release =	snd_seq_release,
2754 	.poll =		snd_seq_poll,
2755 	.unlocked_ioctl =	snd_seq_ioctl,
2756 	.compat_ioctl =	snd_seq_ioctl_compat,
2757 };
2758 
2759 static struct device *seq_dev;
2760 
2761 /*
2762  * register sequencer device
2763  */
2764 int __init snd_sequencer_device_init(void)
2765 {
2766 	int err;
2767 
2768 	err = snd_device_alloc(&seq_dev, NULL);
2769 	if (err < 0)
2770 		return err;
2771 	dev_set_name(seq_dev, "seq");
2772 
2773 	mutex_lock(&register_mutex);
2774 	err = snd_register_device(SNDRV_DEVICE_TYPE_SEQUENCER, NULL, 0,
2775 				  &snd_seq_f_ops, NULL, seq_dev);
2776 	mutex_unlock(&register_mutex);
2777 	if (err < 0) {
2778 		put_device(seq_dev);
2779 		return err;
2780 	}
2781 
2782 	return 0;
2783 }
2784 
2785 
2786 
2787 /*
2788  * unregister sequencer device
2789  */
2790 void snd_sequencer_device_done(void)
2791 {
2792 	snd_unregister_device(seq_dev);
2793 	put_device(seq_dev);
2794 }
2795