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v3.1
 
  1/*
  2 *  ALSA sequencer Memory Manager
  3 *  Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl>
  4 *                        Jaroslav Kysela <perex@perex.cz>
  5 *                2000 by Takashi Iwai <tiwai@suse.de>
  6 *
  7 *   This program is free software; you can redistribute it and/or modify
  8 *   it under the terms of the GNU General Public License as published by
  9 *   the Free Software Foundation; either version 2 of the License, or
 10 *   (at your option) any later version.
 11 *
 12 *   This program is distributed in the hope that it will be useful,
 13 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 14 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15 *   GNU General Public License for more details.
 16 *
 17 *   You should have received a copy of the GNU General Public License
 18 *   along with this program; if not, write to the Free Software
 19 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 20 *
 21 */
 22
 23#include <linux/init.h>
 
 24#include <linux/slab.h>
 25#include <linux/vmalloc.h>
 
 26#include <sound/core.h>
 27
 28#include <sound/seq_kernel.h>
 29#include "seq_memory.h"
 30#include "seq_queue.h"
 31#include "seq_info.h"
 32#include "seq_lock.h"
 33
 34static inline int snd_seq_pool_available(struct snd_seq_pool *pool)
 35{
 36	return pool->total_elements - atomic_read(&pool->counter);
 37}
 38
 39static inline int snd_seq_output_ok(struct snd_seq_pool *pool)
 40{
 41	return snd_seq_pool_available(pool) >= pool->room;
 42}
 43
 44/*
 45 * Variable length event:
 46 * The event like sysex uses variable length type.
 47 * The external data may be stored in three different formats.
 48 * 1) kernel space
 49 *    This is the normal case.
 50 *      ext.data.len = length
 51 *      ext.data.ptr = buffer pointer
 52 * 2) user space
 53 *    When an event is generated via read(), the external data is
 54 *    kept in user space until expanded.
 55 *      ext.data.len = length | SNDRV_SEQ_EXT_USRPTR
 56 *      ext.data.ptr = userspace pointer
 57 * 3) chained cells
 58 *    When the variable length event is enqueued (in prioq or fifo),
 59 *    the external data is decomposed to several cells.
 60 *      ext.data.len = length | SNDRV_SEQ_EXT_CHAINED
 61 *      ext.data.ptr = the additiona cell head
 62 *         -> cell.next -> cell.next -> ..
 63 */
 64
 65/*
 66 * exported:
 67 * call dump function to expand external data.
 68 */
 69
 70static int get_var_len(const struct snd_seq_event *event)
 71{
 72	if ((event->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE)
 73		return -EINVAL;
 74
 75	return event->data.ext.len & ~SNDRV_SEQ_EXT_MASK;
 76}
 77
 78int snd_seq_dump_var_event(const struct snd_seq_event *event,
 79			   snd_seq_dump_func_t func, void *private_data)
 
 80{
 81	int len, err;
 82	struct snd_seq_event_cell *cell;
 83
 84	if ((len = get_var_len(event)) <= 0)
 
 85		return len;
 
 
 
 
 86
 87	if (event->data.ext.len & SNDRV_SEQ_EXT_USRPTR) {
 88		char buf[32];
 89		char __user *curptr = (char __force __user *)event->data.ext.ptr;
 
 
 90		while (len > 0) {
 91			int size = sizeof(buf);
 92			if (len < size)
 93				size = len;
 94			if (copy_from_user(buf, curptr, size))
 95				return -EFAULT;
 96			err = func(private_data, buf, size);
 97			if (err < 0)
 98				return err;
 99			curptr += size;
100			len -= size;
101		}
102		return 0;
103	} if (! (event->data.ext.len & SNDRV_SEQ_EXT_CHAINED)) {
104		return func(private_data, event->data.ext.ptr, len);
105	}
 
 
 
106
107	cell = (struct snd_seq_event_cell *)event->data.ext.ptr;
108	for (; len > 0 && cell; cell = cell->next) {
109		int size = sizeof(struct snd_seq_event);
 
 
 
 
 
 
 
110		if (len < size)
111			size = len;
112		err = func(private_data, &cell->event, size);
113		if (err < 0)
114			return err;
 
115		len -= size;
116	}
117	return 0;
118}
119
 
 
 
 
 
120EXPORT_SYMBOL(snd_seq_dump_var_event);
121
122
123/*
124 * exported:
125 * expand the variable length event to linear buffer space.
126 */
127
128static int seq_copy_in_kernel(char **bufptr, const void *src, int size)
129{
 
 
130	memcpy(*bufptr, src, size);
131	*bufptr += size;
132	return 0;
133}
134
135static int seq_copy_in_user(char __user **bufptr, const void *src, int size)
136{
 
 
137	if (copy_to_user(*bufptr, src, size))
138		return -EFAULT;
139	*bufptr += size;
140	return 0;
141}
142
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
143int snd_seq_expand_var_event(const struct snd_seq_event *event, int count, char *buf,
144			     int in_kernel, int size_aligned)
145{
146	int len, newlen;
147	int err;
148
149	if ((len = get_var_len(event)) < 0)
 
150		return len;
151	newlen = len;
152	if (size_aligned > 0)
153		newlen = roundup(len, size_aligned);
154	if (count < newlen)
155		return -EAGAIN;
156
157	if (event->data.ext.len & SNDRV_SEQ_EXT_USRPTR) {
158		if (! in_kernel)
159			return -EINVAL;
160		if (copy_from_user(buf, (void __force __user *)event->data.ext.ptr, len))
 
 
 
161			return -EFAULT;
162		return newlen;
163	}
164	err = snd_seq_dump_var_event(event,
165				     in_kernel ? (snd_seq_dump_func_t)seq_copy_in_kernel :
166				     (snd_seq_dump_func_t)seq_copy_in_user,
167				     &buf);
168	return err < 0 ? err : newlen;
169}
170
171EXPORT_SYMBOL(snd_seq_expand_var_event);
172
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
173/*
174 * release this cell, free extended data if available
175 */
176
177static inline void free_cell(struct snd_seq_pool *pool,
178			     struct snd_seq_event_cell *cell)
179{
180	cell->next = pool->free;
181	pool->free = cell;
182	atomic_dec(&pool->counter);
183}
184
185void snd_seq_cell_free(struct snd_seq_event_cell * cell)
186{
187	unsigned long flags;
188	struct snd_seq_pool *pool;
189
190	if (snd_BUG_ON(!cell))
191		return;
192	pool = cell->pool;
193	if (snd_BUG_ON(!pool))
194		return;
195
196	spin_lock_irqsave(&pool->lock, flags);
197	free_cell(pool, cell);
198	if (snd_seq_ev_is_variable(&cell->event)) {
199		if (cell->event.data.ext.len & SNDRV_SEQ_EXT_CHAINED) {
200			struct snd_seq_event_cell *curp, *nextptr;
201			curp = cell->event.data.ext.ptr;
202			for (; curp; curp = nextptr) {
203				nextptr = curp->next;
204				curp->next = pool->free;
205				free_cell(pool, curp);
206			}
207		}
208	}
209	if (waitqueue_active(&pool->output_sleep)) {
210		/* has enough space now? */
211		if (snd_seq_output_ok(pool))
212			wake_up(&pool->output_sleep);
213	}
214	spin_unlock_irqrestore(&pool->lock, flags);
215}
216
217
218/*
219 * allocate an event cell.
220 */
221static int snd_seq_cell_alloc(struct snd_seq_pool *pool,
222			      struct snd_seq_event_cell **cellp,
223			      int nonblock, struct file *file)
 
224{
225	struct snd_seq_event_cell *cell;
226	unsigned long flags;
227	int err = -EAGAIN;
228	wait_queue_t wait;
229
230	if (pool == NULL)
231		return -EINVAL;
232
233	*cellp = NULL;
234
235	init_waitqueue_entry(&wait, current);
236	spin_lock_irqsave(&pool->lock, flags);
237	if (pool->ptr == NULL) {	/* not initialized */
238		snd_printd("seq: pool is not initialized\n");
239		err = -EINVAL;
240		goto __error;
241	}
242	while (pool->free == NULL && ! nonblock && ! pool->closing) {
243
244		set_current_state(TASK_INTERRUPTIBLE);
245		add_wait_queue(&pool->output_sleep, &wait);
246		spin_unlock_irq(&pool->lock);
 
 
247		schedule();
248		spin_lock_irq(&pool->lock);
 
 
249		remove_wait_queue(&pool->output_sleep, &wait);
250		/* interrupted? */
251		if (signal_pending(current)) {
252			err = -ERESTARTSYS;
253			goto __error;
254		}
255	}
256	if (pool->closing) { /* closing.. */
257		err = -ENOMEM;
258		goto __error;
259	}
260
261	cell = pool->free;
262	if (cell) {
263		int used;
264		pool->free = cell->next;
265		atomic_inc(&pool->counter);
266		used = atomic_read(&pool->counter);
267		if (pool->max_used < used)
268			pool->max_used = used;
269		pool->event_alloc_success++;
270		/* clear cell pointers */
271		cell->next = NULL;
272		err = 0;
273	} else
274		pool->event_alloc_failures++;
275	*cellp = cell;
276
277__error:
278	spin_unlock_irqrestore(&pool->lock, flags);
279	return err;
280}
281
282
283/*
284 * duplicate the event to a cell.
285 * if the event has external data, the data is decomposed to additional
286 * cells.
287 */
288int snd_seq_event_dup(struct snd_seq_pool *pool, struct snd_seq_event *event,
289		      struct snd_seq_event_cell **cellp, int nonblock,
290		      struct file *file)
291{
292	int ncells, err;
293	unsigned int extlen;
294	struct snd_seq_event_cell *cell;
 
295
296	*cellp = NULL;
297
298	ncells = 0;
299	extlen = 0;
300	if (snd_seq_ev_is_variable(event)) {
301		extlen = event->data.ext.len & ~SNDRV_SEQ_EXT_MASK;
302		ncells = (extlen + sizeof(struct snd_seq_event) - 1) / sizeof(struct snd_seq_event);
303	}
304	if (ncells >= pool->total_elements)
305		return -ENOMEM;
306
307	err = snd_seq_cell_alloc(pool, &cell, nonblock, file);
308	if (err < 0)
309		return err;
310
311	/* copy the event */
312	cell->event = *event;
 
 
 
 
 
313
314	/* decompose */
315	if (snd_seq_ev_is_variable(event)) {
316		int len = extlen;
317		int is_chained = event->data.ext.len & SNDRV_SEQ_EXT_CHAINED;
318		int is_usrptr = event->data.ext.len & SNDRV_SEQ_EXT_USRPTR;
319		struct snd_seq_event_cell *src, *tmp, *tail;
320		char *buf;
321
322		cell->event.data.ext.len = extlen | SNDRV_SEQ_EXT_CHAINED;
323		cell->event.data.ext.ptr = NULL;
324
325		src = (struct snd_seq_event_cell *)event->data.ext.ptr;
326		buf = (char *)event->data.ext.ptr;
327		tail = NULL;
328
329		while (ncells-- > 0) {
330			int size = sizeof(struct snd_seq_event);
331			if (len < size)
332				size = len;
333			err = snd_seq_cell_alloc(pool, &tmp, nonblock, file);
 
334			if (err < 0)
335				goto __error;
336			if (cell->event.data.ext.ptr == NULL)
337				cell->event.data.ext.ptr = tmp;
338			if (tail)
339				tail->next = tmp;
340			tail = tmp;
341			/* copy chunk */
342			if (is_chained && src) {
343				tmp->event = src->event;
344				src = src->next;
345			} else if (is_usrptr) {
346				if (copy_from_user(&tmp->event, (char __force __user *)buf, size)) {
347					err = -EFAULT;
348					goto __error;
349				}
350			} else {
351				memcpy(&tmp->event, buf, size);
352			}
353			buf += size;
354			len -= size;
355		}
356	}
357
358	*cellp = cell;
359	return 0;
360
361__error:
362	snd_seq_cell_free(cell);
363	return err;
364}
365  
366
367/* poll wait */
368int snd_seq_pool_poll_wait(struct snd_seq_pool *pool, struct file *file,
369			   poll_table *wait)
370{
371	poll_wait(file, &pool->output_sleep, wait);
372	return snd_seq_output_ok(pool);
373}
374
375
376/* allocate room specified number of events */
377int snd_seq_pool_init(struct snd_seq_pool *pool)
378{
379	int cell;
380	struct snd_seq_event_cell *cellptr;
381	unsigned long flags;
382
383	if (snd_BUG_ON(!pool))
384		return -EINVAL;
385	if (pool->ptr)			/* should be atomic? */
386		return 0;
387
388	pool->ptr = vmalloc(sizeof(struct snd_seq_event_cell) * pool->size);
389	if (pool->ptr == NULL) {
390		snd_printd("seq: malloc for sequencer events failed\n");
 
391		return -ENOMEM;
392	}
393
394	/* add new cells to the free cell list */
395	spin_lock_irqsave(&pool->lock, flags);
 
 
 
 
 
 
 
396	pool->free = NULL;
397
398	for (cell = 0; cell < pool->size; cell++) {
399		cellptr = pool->ptr + cell;
400		cellptr->pool = pool;
401		cellptr->next = pool->free;
402		pool->free = cellptr;
403	}
404	pool->room = (pool->size + 1) / 2;
405
406	/* init statistics */
407	pool->max_used = 0;
408	pool->total_elements = pool->size;
409	spin_unlock_irqrestore(&pool->lock, flags);
410	return 0;
411}
412
 
 
 
 
 
 
 
 
 
 
 
 
413/* remove events */
414int snd_seq_pool_done(struct snd_seq_pool *pool)
415{
416	unsigned long flags;
417	struct snd_seq_event_cell *ptr;
418	int max_count = 5 * HZ;
419
420	if (snd_BUG_ON(!pool))
421		return -EINVAL;
422
423	/* wait for closing all threads */
424	spin_lock_irqsave(&pool->lock, flags);
425	pool->closing = 1;
426	spin_unlock_irqrestore(&pool->lock, flags);
427
428	if (waitqueue_active(&pool->output_sleep))
429		wake_up(&pool->output_sleep);
430
431	while (atomic_read(&pool->counter) > 0) {
432		if (max_count == 0) {
433			snd_printk(KERN_WARNING "snd_seq_pool_done timeout: %d cells remain\n", atomic_read(&pool->counter));
434			break;
435		}
436		schedule_timeout_uninterruptible(1);
437		max_count--;
438	}
439	
440	/* release all resources */
441	spin_lock_irqsave(&pool->lock, flags);
442	ptr = pool->ptr;
443	pool->ptr = NULL;
444	pool->free = NULL;
445	pool->total_elements = 0;
446	spin_unlock_irqrestore(&pool->lock, flags);
447
448	vfree(ptr);
449
450	spin_lock_irqsave(&pool->lock, flags);
451	pool->closing = 0;
452	spin_unlock_irqrestore(&pool->lock, flags);
453
454	return 0;
455}
456
457
458/* init new memory pool */
459struct snd_seq_pool *snd_seq_pool_new(int poolsize)
460{
461	struct snd_seq_pool *pool;
462
463	/* create pool block */
464	pool = kzalloc(sizeof(*pool), GFP_KERNEL);
465	if (pool == NULL) {
466		snd_printd("seq: malloc failed for pool\n");
467		return NULL;
468	}
469	spin_lock_init(&pool->lock);
470	pool->ptr = NULL;
471	pool->free = NULL;
472	pool->total_elements = 0;
473	atomic_set(&pool->counter, 0);
474	pool->closing = 0;
475	init_waitqueue_head(&pool->output_sleep);
476	
477	pool->size = poolsize;
478
479	/* init statistics */
480	pool->max_used = 0;
481	return pool;
482}
483
484/* remove memory pool */
485int snd_seq_pool_delete(struct snd_seq_pool **ppool)
486{
487	struct snd_seq_pool *pool = *ppool;
488
489	*ppool = NULL;
490	if (pool == NULL)
491		return 0;
 
492	snd_seq_pool_done(pool);
493	kfree(pool);
494	return 0;
495}
496
497/* initialize sequencer memory */
498int __init snd_sequencer_memory_init(void)
499{
500	return 0;
501}
502
503/* release sequencer memory */
504void __exit snd_sequencer_memory_done(void)
505{
506}
507
508
509/* exported to seq_clientmgr.c */
510void snd_seq_info_pool(struct snd_info_buffer *buffer,
511		       struct snd_seq_pool *pool, char *space)
512{
513	if (pool == NULL)
514		return;
515	snd_iprintf(buffer, "%sPool size          : %d\n", space, pool->total_elements);
516	snd_iprintf(buffer, "%sCells in use       : %d\n", space, atomic_read(&pool->counter));
517	snd_iprintf(buffer, "%sPeak cells in use  : %d\n", space, pool->max_used);
518	snd_iprintf(buffer, "%sAlloc success      : %d\n", space, pool->event_alloc_success);
519	snd_iprintf(buffer, "%sAlloc failures     : %d\n", space, pool->event_alloc_failures);
520}
v6.8
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  ALSA sequencer Memory Manager
  4 *  Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl>
  5 *                        Jaroslav Kysela <perex@perex.cz>
  6 *                2000 by Takashi Iwai <tiwai@suse.de>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  7 */
  8
  9#include <linux/init.h>
 10#include <linux/export.h>
 11#include <linux/slab.h>
 12#include <linux/sched/signal.h>
 13#include <linux/mm.h>
 14#include <sound/core.h>
 15
 16#include <sound/seq_kernel.h>
 17#include "seq_memory.h"
 18#include "seq_queue.h"
 19#include "seq_info.h"
 20#include "seq_lock.h"
 21
 22static inline int snd_seq_pool_available(struct snd_seq_pool *pool)
 23{
 24	return pool->total_elements - atomic_read(&pool->counter);
 25}
 26
 27static inline int snd_seq_output_ok(struct snd_seq_pool *pool)
 28{
 29	return snd_seq_pool_available(pool) >= pool->room;
 30}
 31
 32/*
 33 * Variable length event:
 34 * The event like sysex uses variable length type.
 35 * The external data may be stored in three different formats.
 36 * 1) kernel space
 37 *    This is the normal case.
 38 *      ext.data.len = length
 39 *      ext.data.ptr = buffer pointer
 40 * 2) user space
 41 *    When an event is generated via read(), the external data is
 42 *    kept in user space until expanded.
 43 *      ext.data.len = length | SNDRV_SEQ_EXT_USRPTR
 44 *      ext.data.ptr = userspace pointer
 45 * 3) chained cells
 46 *    When the variable length event is enqueued (in prioq or fifo),
 47 *    the external data is decomposed to several cells.
 48 *      ext.data.len = length | SNDRV_SEQ_EXT_CHAINED
 49 *      ext.data.ptr = the additiona cell head
 50 *         -> cell.next -> cell.next -> ..
 51 */
 52
 53/*
 54 * exported:
 55 * call dump function to expand external data.
 56 */
 57
 58static int get_var_len(const struct snd_seq_event *event)
 59{
 60	if ((event->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE)
 61		return -EINVAL;
 62
 63	return event->data.ext.len & ~SNDRV_SEQ_EXT_MASK;
 64}
 65
 66static int dump_var_event(const struct snd_seq_event *event,
 67			  snd_seq_dump_func_t func, void *private_data,
 68			  int offset, int maxlen)
 69{
 70	int len, err;
 71	struct snd_seq_event_cell *cell;
 72
 73	len = get_var_len(event);
 74	if (len <= 0)
 75		return len;
 76	if (len <= offset)
 77		return 0;
 78	if (maxlen && len > offset + maxlen)
 79		len = offset + maxlen;
 80
 81	if (event->data.ext.len & SNDRV_SEQ_EXT_USRPTR) {
 82		char buf[32];
 83		char __user *curptr = (char __force __user *)event->data.ext.ptr;
 84		curptr += offset;
 85		len -= offset;
 86		while (len > 0) {
 87			int size = sizeof(buf);
 88			if (len < size)
 89				size = len;
 90			if (copy_from_user(buf, curptr, size))
 91				return -EFAULT;
 92			err = func(private_data, buf, size);
 93			if (err < 0)
 94				return err;
 95			curptr += size;
 96			len -= size;
 97		}
 98		return 0;
 
 
 99	}
100	if (!(event->data.ext.len & SNDRV_SEQ_EXT_CHAINED))
101		return func(private_data, event->data.ext.ptr + offset,
102			    len - offset);
103
104	cell = (struct snd_seq_event_cell *)event->data.ext.ptr;
105	for (; len > 0 && cell; cell = cell->next) {
106		int size = sizeof(struct snd_seq_event);
107		char *curptr = (char *)&cell->event;
108
109		if (offset >= size) {
110			offset -= size;
111			len -= size;
112			continue;
113		}
114		if (len < size)
115			size = len;
116		err = func(private_data, curptr + offset, size - offset);
117		if (err < 0)
118			return err;
119		offset = 0;
120		len -= size;
121	}
122	return 0;
123}
124
125int snd_seq_dump_var_event(const struct snd_seq_event *event,
126			   snd_seq_dump_func_t func, void *private_data)
127{
128	return dump_var_event(event, func, private_data, 0, 0);
129}
130EXPORT_SYMBOL(snd_seq_dump_var_event);
131
132
133/*
134 * exported:
135 * expand the variable length event to linear buffer space.
136 */
137
138static int seq_copy_in_kernel(void *ptr, void *src, int size)
139{
140	char **bufptr = ptr;
141
142	memcpy(*bufptr, src, size);
143	*bufptr += size;
144	return 0;
145}
146
147static int seq_copy_in_user(void *ptr, void *src, int size)
148{
149	char __user **bufptr = ptr;
150
151	if (copy_to_user(*bufptr, src, size))
152		return -EFAULT;
153	*bufptr += size;
154	return 0;
155}
156
157static int expand_var_event(const struct snd_seq_event *event,
158			    int offset, int size, char *buf, bool in_kernel)
159{
160	if (event->data.ext.len & SNDRV_SEQ_EXT_USRPTR) {
161		if (! in_kernel)
162			return -EINVAL;
163		if (copy_from_user(buf,
164				   (char __force __user *)event->data.ext.ptr + offset,
165				   size))
166			return -EFAULT;
167		return 0;
168	}
169	return dump_var_event(event,
170			     in_kernel ? seq_copy_in_kernel : seq_copy_in_user,
171			     &buf, offset, size);
172}
173
174int snd_seq_expand_var_event(const struct snd_seq_event *event, int count, char *buf,
175			     int in_kernel, int size_aligned)
176{
177	int len, newlen, err;
 
178
179	len = get_var_len(event);
180	if (len < 0)
181		return len;
182	newlen = len;
183	if (size_aligned > 0)
184		newlen = roundup(len, size_aligned);
185	if (count < newlen)
186		return -EAGAIN;
187	err = expand_var_event(event, 0, len, buf, in_kernel);
188	if (err < 0)
189		return err;
190	if (len != newlen) {
191		if (in_kernel)
192			memset(buf + len, 0, newlen - len);
193		else if (clear_user((__force void __user *)buf + len,
194				    newlen - len))
195			return -EFAULT;
 
196	}
197	return newlen;
 
 
 
 
198}
 
199EXPORT_SYMBOL(snd_seq_expand_var_event);
200
201int snd_seq_expand_var_event_at(const struct snd_seq_event *event, int count,
202				char *buf, int offset)
203{
204	int len, err;
205
206	len = get_var_len(event);
207	if (len < 0)
208		return len;
209	if (len <= offset)
210		return 0;
211	len -= offset;
212	if (len > count)
213		len = count;
214	err = expand_var_event(event, offset, count, buf, true);
215	if (err < 0)
216		return err;
217	return len;
218}
219EXPORT_SYMBOL_GPL(snd_seq_expand_var_event_at);
220
221/*
222 * release this cell, free extended data if available
223 */
224
225static inline void free_cell(struct snd_seq_pool *pool,
226			     struct snd_seq_event_cell *cell)
227{
228	cell->next = pool->free;
229	pool->free = cell;
230	atomic_dec(&pool->counter);
231}
232
233void snd_seq_cell_free(struct snd_seq_event_cell * cell)
234{
235	unsigned long flags;
236	struct snd_seq_pool *pool;
237
238	if (snd_BUG_ON(!cell))
239		return;
240	pool = cell->pool;
241	if (snd_BUG_ON(!pool))
242		return;
243
244	spin_lock_irqsave(&pool->lock, flags);
245	free_cell(pool, cell);
246	if (snd_seq_ev_is_variable(&cell->event)) {
247		if (cell->event.data.ext.len & SNDRV_SEQ_EXT_CHAINED) {
248			struct snd_seq_event_cell *curp, *nextptr;
249			curp = cell->event.data.ext.ptr;
250			for (; curp; curp = nextptr) {
251				nextptr = curp->next;
252				curp->next = pool->free;
253				free_cell(pool, curp);
254			}
255		}
256	}
257	if (waitqueue_active(&pool->output_sleep)) {
258		/* has enough space now? */
259		if (snd_seq_output_ok(pool))
260			wake_up(&pool->output_sleep);
261	}
262	spin_unlock_irqrestore(&pool->lock, flags);
263}
264
265
266/*
267 * allocate an event cell.
268 */
269static int snd_seq_cell_alloc(struct snd_seq_pool *pool,
270			      struct snd_seq_event_cell **cellp,
271			      int nonblock, struct file *file,
272			      struct mutex *mutexp)
273{
274	struct snd_seq_event_cell *cell;
275	unsigned long flags;
276	int err = -EAGAIN;
277	wait_queue_entry_t wait;
278
279	if (pool == NULL)
280		return -EINVAL;
281
282	*cellp = NULL;
283
284	init_waitqueue_entry(&wait, current);
285	spin_lock_irqsave(&pool->lock, flags);
286	if (pool->ptr == NULL) {	/* not initialized */
287		pr_debug("ALSA: seq: pool is not initialized\n");
288		err = -EINVAL;
289		goto __error;
290	}
291	while (pool->free == NULL && ! nonblock && ! pool->closing) {
292
293		set_current_state(TASK_INTERRUPTIBLE);
294		add_wait_queue(&pool->output_sleep, &wait);
295		spin_unlock_irqrestore(&pool->lock, flags);
296		if (mutexp)
297			mutex_unlock(mutexp);
298		schedule();
299		if (mutexp)
300			mutex_lock(mutexp);
301		spin_lock_irqsave(&pool->lock, flags);
302		remove_wait_queue(&pool->output_sleep, &wait);
303		/* interrupted? */
304		if (signal_pending(current)) {
305			err = -ERESTARTSYS;
306			goto __error;
307		}
308	}
309	if (pool->closing) { /* closing.. */
310		err = -ENOMEM;
311		goto __error;
312	}
313
314	cell = pool->free;
315	if (cell) {
316		int used;
317		pool->free = cell->next;
318		atomic_inc(&pool->counter);
319		used = atomic_read(&pool->counter);
320		if (pool->max_used < used)
321			pool->max_used = used;
322		pool->event_alloc_success++;
323		/* clear cell pointers */
324		cell->next = NULL;
325		err = 0;
326	} else
327		pool->event_alloc_failures++;
328	*cellp = cell;
329
330__error:
331	spin_unlock_irqrestore(&pool->lock, flags);
332	return err;
333}
334
335
336/*
337 * duplicate the event to a cell.
338 * if the event has external data, the data is decomposed to additional
339 * cells.
340 */
341int snd_seq_event_dup(struct snd_seq_pool *pool, struct snd_seq_event *event,
342		      struct snd_seq_event_cell **cellp, int nonblock,
343		      struct file *file, struct mutex *mutexp)
344{
345	int ncells, err;
346	unsigned int extlen;
347	struct snd_seq_event_cell *cell;
348	int size;
349
350	*cellp = NULL;
351
352	ncells = 0;
353	extlen = 0;
354	if (snd_seq_ev_is_variable(event)) {
355		extlen = event->data.ext.len & ~SNDRV_SEQ_EXT_MASK;
356		ncells = DIV_ROUND_UP(extlen, sizeof(struct snd_seq_event));
357	}
358	if (ncells >= pool->total_elements)
359		return -ENOMEM;
360
361	err = snd_seq_cell_alloc(pool, &cell, nonblock, file, mutexp);
362	if (err < 0)
363		return err;
364
365	/* copy the event */
366	size = snd_seq_event_packet_size(event);
367	memcpy(&cell->ump, event, size);
368#if IS_ENABLED(CONFIG_SND_SEQ_UMP)
369	if (size < sizeof(cell->event))
370		cell->ump.raw.extra = 0;
371#endif
372
373	/* decompose */
374	if (snd_seq_ev_is_variable(event)) {
375		int len = extlen;
376		int is_chained = event->data.ext.len & SNDRV_SEQ_EXT_CHAINED;
377		int is_usrptr = event->data.ext.len & SNDRV_SEQ_EXT_USRPTR;
378		struct snd_seq_event_cell *src, *tmp, *tail;
379		char *buf;
380
381		cell->event.data.ext.len = extlen | SNDRV_SEQ_EXT_CHAINED;
382		cell->event.data.ext.ptr = NULL;
383
384		src = (struct snd_seq_event_cell *)event->data.ext.ptr;
385		buf = (char *)event->data.ext.ptr;
386		tail = NULL;
387
388		while (ncells-- > 0) {
389			size = sizeof(struct snd_seq_event);
390			if (len < size)
391				size = len;
392			err = snd_seq_cell_alloc(pool, &tmp, nonblock, file,
393						 mutexp);
394			if (err < 0)
395				goto __error;
396			if (cell->event.data.ext.ptr == NULL)
397				cell->event.data.ext.ptr = tmp;
398			if (tail)
399				tail->next = tmp;
400			tail = tmp;
401			/* copy chunk */
402			if (is_chained && src) {
403				tmp->event = src->event;
404				src = src->next;
405			} else if (is_usrptr) {
406				if (copy_from_user(&tmp->event, (char __force __user *)buf, size)) {
407					err = -EFAULT;
408					goto __error;
409				}
410			} else {
411				memcpy(&tmp->event, buf, size);
412			}
413			buf += size;
414			len -= size;
415		}
416	}
417
418	*cellp = cell;
419	return 0;
420
421__error:
422	snd_seq_cell_free(cell);
423	return err;
424}
425  
426
427/* poll wait */
428int snd_seq_pool_poll_wait(struct snd_seq_pool *pool, struct file *file,
429			   poll_table *wait)
430{
431	poll_wait(file, &pool->output_sleep, wait);
432	return snd_seq_output_ok(pool);
433}
434
435
436/* allocate room specified number of events */
437int snd_seq_pool_init(struct snd_seq_pool *pool)
438{
439	int cell;
440	struct snd_seq_event_cell *cellptr;
 
441
442	if (snd_BUG_ON(!pool))
443		return -EINVAL;
 
 
444
445	cellptr = kvmalloc_array(pool->size,
446				 sizeof(struct snd_seq_event_cell),
447				 GFP_KERNEL);
448	if (!cellptr)
449		return -ENOMEM;
 
450
451	/* add new cells to the free cell list */
452	spin_lock_irq(&pool->lock);
453	if (pool->ptr) {
454		spin_unlock_irq(&pool->lock);
455		kvfree(cellptr);
456		return 0;
457	}
458
459	pool->ptr = cellptr;
460	pool->free = NULL;
461
462	for (cell = 0; cell < pool->size; cell++) {
463		cellptr = pool->ptr + cell;
464		cellptr->pool = pool;
465		cellptr->next = pool->free;
466		pool->free = cellptr;
467	}
468	pool->room = (pool->size + 1) / 2;
469
470	/* init statistics */
471	pool->max_used = 0;
472	pool->total_elements = pool->size;
473	spin_unlock_irq(&pool->lock);
474	return 0;
475}
476
477/* refuse the further insertion to the pool */
478void snd_seq_pool_mark_closing(struct snd_seq_pool *pool)
479{
480	unsigned long flags;
481
482	if (snd_BUG_ON(!pool))
483		return;
484	spin_lock_irqsave(&pool->lock, flags);
485	pool->closing = 1;
486	spin_unlock_irqrestore(&pool->lock, flags);
487}
488
489/* remove events */
490int snd_seq_pool_done(struct snd_seq_pool *pool)
491{
 
492	struct snd_seq_event_cell *ptr;
 
493
494	if (snd_BUG_ON(!pool))
495		return -EINVAL;
496
497	/* wait for closing all threads */
 
 
 
 
498	if (waitqueue_active(&pool->output_sleep))
499		wake_up(&pool->output_sleep);
500
501	while (atomic_read(&pool->counter) > 0)
 
 
 
 
502		schedule_timeout_uninterruptible(1);
 
 
503	
504	/* release all resources */
505	spin_lock_irq(&pool->lock);
506	ptr = pool->ptr;
507	pool->ptr = NULL;
508	pool->free = NULL;
509	pool->total_elements = 0;
510	spin_unlock_irq(&pool->lock);
511
512	kvfree(ptr);
513
514	spin_lock_irq(&pool->lock);
515	pool->closing = 0;
516	spin_unlock_irq(&pool->lock);
517
518	return 0;
519}
520
521
522/* init new memory pool */
523struct snd_seq_pool *snd_seq_pool_new(int poolsize)
524{
525	struct snd_seq_pool *pool;
526
527	/* create pool block */
528	pool = kzalloc(sizeof(*pool), GFP_KERNEL);
529	if (!pool)
 
530		return NULL;
 
531	spin_lock_init(&pool->lock);
532	pool->ptr = NULL;
533	pool->free = NULL;
534	pool->total_elements = 0;
535	atomic_set(&pool->counter, 0);
536	pool->closing = 0;
537	init_waitqueue_head(&pool->output_sleep);
538	
539	pool->size = poolsize;
540
541	/* init statistics */
542	pool->max_used = 0;
543	return pool;
544}
545
546/* remove memory pool */
547int snd_seq_pool_delete(struct snd_seq_pool **ppool)
548{
549	struct snd_seq_pool *pool = *ppool;
550
551	*ppool = NULL;
552	if (pool == NULL)
553		return 0;
554	snd_seq_pool_mark_closing(pool);
555	snd_seq_pool_done(pool);
556	kfree(pool);
557	return 0;
558}
 
 
 
 
 
 
 
 
 
 
 
 
559
560/* exported to seq_clientmgr.c */
561void snd_seq_info_pool(struct snd_info_buffer *buffer,
562		       struct snd_seq_pool *pool, char *space)
563{
564	if (pool == NULL)
565		return;
566	snd_iprintf(buffer, "%sPool size          : %d\n", space, pool->total_elements);
567	snd_iprintf(buffer, "%sCells in use       : %d\n", space, atomic_read(&pool->counter));
568	snd_iprintf(buffer, "%sPeak cells in use  : %d\n", space, pool->max_used);
569	snd_iprintf(buffer, "%sAlloc success      : %d\n", space, pool->event_alloc_success);
570	snd_iprintf(buffer, "%sAlloc failures     : %d\n", space, pool->event_alloc_failures);
571}