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