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Committer: Michael Beasley <mike@snafu.setup>
[mikesnafu-overlay.git] / sound / core / seq / seq_memory.c
blob0cf6ac4773187cca81cf511258083f060bd9cfc6
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
34 static inline int snd_seq_pool_available(struct snd_seq_pool *pool)
35 {
36 return pool->total_elements - atomic_read(&pool->counter);
37 }
38
39 static 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
70 static 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
78 int 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 __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
120 EXPORT_SYMBOL(snd_seq_dump_var_event);
121
122
123 /*
124 * exported:
125 * expand the variable length event to linear buffer space.
126 */
127
128 static 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
135 static 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
143 int 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 __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
171 EXPORT_SYMBOL(snd_seq_expand_var_event);
172
173 /*
174 * release this cell, free extended data if available
175 */
176
177 static 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
185 void snd_seq_cell_free(struct snd_seq_event_cell * cell)
186 {
187 unsigned long flags;
188 struct snd_seq_pool *pool;
189
190 snd_assert(cell != NULL, return);
191 pool = cell->pool;
192 snd_assert(pool != NULL, return);
193
194 spin_lock_irqsave(&pool->lock, flags);
195 free_cell(pool, cell);
196 if (snd_seq_ev_is_variable(&cell->event)) {
197 if (cell->event.data.ext.len & SNDRV_SEQ_EXT_CHAINED) {
198 struct snd_seq_event_cell *curp, *nextptr;
199 curp = cell->event.data.ext.ptr;
200 for (; curp; curp = nextptr) {
201 nextptr = curp->next;
202 curp->next = pool->free;
203 free_cell(pool, curp);
204 }
205 }
206 }
207 if (waitqueue_active(&pool->output_sleep)) {
208 /* has enough space now? */
209 if (snd_seq_output_ok(pool))
210 wake_up(&pool->output_sleep);
211 }
212 spin_unlock_irqrestore(&pool->lock, flags);
213 }
214
215
216 /*
217 * allocate an event cell.
218 */
219 static int snd_seq_cell_alloc(struct snd_seq_pool *pool,
220 struct snd_seq_event_cell **cellp,
221 int nonblock, struct file *file)
222 {
223 struct snd_seq_event_cell *cell;
224 unsigned long flags;
225 int err = -EAGAIN;
226 wait_queue_t wait;
227
228 if (pool == NULL)
229 return -EINVAL;
230
231 *cellp = NULL;
232
233 init_waitqueue_entry(&wait, current);
234 spin_lock_irqsave(&pool->lock, flags);
235 if (pool->ptr == NULL) { /* not initialized */
236 snd_printd("seq: pool is not initialized\n");
237 err = -EINVAL;
238 goto __error;
239 }
240 while (pool->free == NULL && ! nonblock && ! pool->closing) {
241
242 set_current_state(TASK_INTERRUPTIBLE);
243 add_wait_queue(&pool->output_sleep, &wait);
244 spin_unlock_irq(&pool->lock);
245 schedule();
246 spin_lock_irq(&pool->lock);
247 remove_wait_queue(&pool->output_sleep, &wait);
248 /* interrupted? */
249 if (signal_pending(current)) {
250 err = -ERESTARTSYS;
251 goto __error;
252 }
253 }
254 if (pool->closing) { /* closing.. */
255 err = -ENOMEM;
256 goto __error;
257 }
258
259 cell = pool->free;
260 if (cell) {
261 int used;
262 pool->free = cell->next;
263 atomic_inc(&pool->counter);
264 used = atomic_read(&pool->counter);
265 if (pool->max_used < used)
266 pool->max_used = used;
267 pool->event_alloc_success++;
268 /* clear cell pointers */
269 cell->next = NULL;
270 err = 0;
271 } else
272 pool->event_alloc_failures++;
273 *cellp = cell;
274
275 __error:
276 spin_unlock_irqrestore(&pool->lock, flags);
277 return err;
278 }
279
280
281 /*
282 * duplicate the event to a cell.
283 * if the event has external data, the data is decomposed to additional
284 * cells.
285 */
286 int snd_seq_event_dup(struct snd_seq_pool *pool, struct snd_seq_event *event,
287 struct snd_seq_event_cell **cellp, int nonblock,
288 struct file *file)
289 {
290 int ncells, err;
291 unsigned int extlen;
292 struct snd_seq_event_cell *cell;
293
294 *cellp = NULL;
295
296 ncells = 0;
297 extlen = 0;
298 if (snd_seq_ev_is_variable(event)) {
299 extlen = event->data.ext.len & ~SNDRV_SEQ_EXT_MASK;
300 ncells = (extlen + sizeof(struct snd_seq_event) - 1) / sizeof(struct snd_seq_event);
301 }
302 if (ncells >= pool->total_elements)
303 return -ENOMEM;
304
305 err = snd_seq_cell_alloc(pool, &cell, nonblock, file);
306 if (err < 0)
307 return err;
308
309 /* copy the event */
310 cell->event = *event;
311
312 /* decompose */
313 if (snd_seq_ev_is_variable(event)) {
314 int len = extlen;
315 int is_chained = event->data.ext.len & SNDRV_SEQ_EXT_CHAINED;
316 int is_usrptr = event->data.ext.len & SNDRV_SEQ_EXT_USRPTR;
317 struct snd_seq_event_cell *src, *tmp, *tail;
318 char *buf;
319
320 cell->event.data.ext.len = extlen | SNDRV_SEQ_EXT_CHAINED;
321 cell->event.data.ext.ptr = NULL;
322
323 src = (struct snd_seq_event_cell *)event->data.ext.ptr;
324 buf = (char *)event->data.ext.ptr;
325 tail = NULL;
326
327 while (ncells-- > 0) {
328 int size = sizeof(struct snd_seq_event);
329 if (len < size)
330 size = len;
331 err = snd_seq_cell_alloc(pool, &tmp, nonblock, file);
332 if (err < 0)
333 goto __error;
334 if (cell->event.data.ext.ptr == NULL)
335 cell->event.data.ext.ptr = tmp;
336 if (tail)
337 tail->next = tmp;
338 tail = tmp;
339 /* copy chunk */
340 if (is_chained && src) {
341 tmp->event = src->event;
342 src = src->next;
343 } else if (is_usrptr) {
344 if (copy_from_user(&tmp->event, (char __user *)buf, size)) {
345 err = -EFAULT;
346 goto __error;
347 }
348 } else {
349 memcpy(&tmp->event, buf, size);
350 }
351 buf += size;
352 len -= size;
353 }
354 }
355
356 *cellp = cell;
357 return 0;
358
359 __error:
360 snd_seq_cell_free(cell);
361 return err;
362 }
363
364
365 /* poll wait */
366 int snd_seq_pool_poll_wait(struct snd_seq_pool *pool, struct file *file,
367 poll_table *wait)
368 {
369 poll_wait(file, &pool->output_sleep, wait);
370 return snd_seq_output_ok(pool);
371 }
372
373
374 /* allocate room specified number of events */
375 int snd_seq_pool_init(struct snd_seq_pool *pool)
376 {
377 int cell;
378 struct snd_seq_event_cell *cellptr;
379 unsigned long flags;
380
381 snd_assert(pool != NULL, return -EINVAL);
382 if (pool->ptr) /* should be atomic? */
383 return 0;
384
385 pool->ptr = vmalloc(sizeof(struct snd_seq_event_cell) * pool->size);
386 if (pool->ptr == NULL) {
387 snd_printd("seq: malloc for sequencer events failed\n");
388 return -ENOMEM;
389 }
390
391 /* add new cells to the free cell list */
392 spin_lock_irqsave(&pool->lock, flags);
393 pool->free = NULL;
394
395 for (cell = 0; cell < pool->size; cell++) {
396 cellptr = pool->ptr + cell;
397 cellptr->pool = pool;
398 cellptr->next = pool->free;
399 pool->free = cellptr;
400 }
401 pool->room = (pool->size + 1) / 2;
402
403 /* init statistics */
404 pool->max_used = 0;
405 pool->total_elements = pool->size;
406 spin_unlock_irqrestore(&pool->lock, flags);
407 return 0;
408 }
409
410 /* remove events */
411 int snd_seq_pool_done(struct snd_seq_pool *pool)
412 {
413 unsigned long flags;
414 struct snd_seq_event_cell *ptr;
415 int max_count = 5 * HZ;
416
417 snd_assert(pool != NULL, return -EINVAL);
418
419 /* wait for closing all threads */
420 spin_lock_irqsave(&pool->lock, flags);
421 pool->closing = 1;
422 spin_unlock_irqrestore(&pool->lock, flags);
423
424 if (waitqueue_active(&pool->output_sleep))
425 wake_up(&pool->output_sleep);
426
427 while (atomic_read(&pool->counter) > 0) {
428 if (max_count == 0) {
429 snd_printk(KERN_WARNING "snd_seq_pool_done timeout: %d cells remain\n", atomic_read(&pool->counter));
430 break;
431 }
432 schedule_timeout_uninterruptible(1);
433 max_count--;
434 }
435
436 /* release all resources */
437 spin_lock_irqsave(&pool->lock, flags);
438 ptr = pool->ptr;
439 pool->ptr = NULL;
440 pool->free = NULL;
441 pool->total_elements = 0;
442 spin_unlock_irqrestore(&pool->lock, flags);
443
444 vfree(ptr);
445
446 spin_lock_irqsave(&pool->lock, flags);
447 pool->closing = 0;
448 spin_unlock_irqrestore(&pool->lock, flags);
449
450 return 0;
451 }
452
453
454 /* init new memory pool */
455 struct snd_seq_pool *snd_seq_pool_new(int poolsize)
456 {
457 struct snd_seq_pool *pool;
458
459 /* create pool block */
460 pool = kzalloc(sizeof(*pool), GFP_KERNEL);
461 if (pool == NULL) {
462 snd_printd("seq: malloc failed for pool\n");
463 return NULL;
464 }
465 spin_lock_init(&pool->lock);
466 pool->ptr = NULL;
467 pool->free = NULL;
468 pool->total_elements = 0;
469 atomic_set(&pool->counter, 0);
470 pool->closing = 0;
471 init_waitqueue_head(&pool->output_sleep);
472
473 pool->size = poolsize;
474
475 /* init statistics */
476 pool->max_used = 0;
477 return pool;
478 }
479
480 /* remove memory pool */
481 int snd_seq_pool_delete(struct snd_seq_pool **ppool)
482 {
483 struct snd_seq_pool *pool = *ppool;
484
485 *ppool = NULL;
486 if (pool == NULL)
487 return 0;
488 snd_seq_pool_done(pool);
489 kfree(pool);
490 return 0;
491 }
492
493 /* initialize sequencer memory */
494 int __init snd_sequencer_memory_init(void)
495 {
496 return 0;
497 }
498
499 /* release sequencer memory */
500 void __exit snd_sequencer_memory_done(void)
501 {
502 }
503
504
505 /* exported to seq_clientmgr.c */
506 void snd_seq_info_pool(struct snd_info_buffer *buffer,
507 struct snd_seq_pool *pool, char *space)
508 {
509 if (pool == NULL)
510 return;
511 snd_iprintf(buffer, "%sPool size : %d\n", space, pool->total_elements);
512 snd_iprintf(buffer, "%sCells in use : %d\n", space, atomic_read(&pool->counter));
513 snd_iprintf(buffer, "%sPeak cells in use : %d\n", space, pool->max_used);
514 snd_iprintf(buffer, "%sAlloc success : %d\n", space, pool->event_alloc_success);
515 snd_iprintf(buffer, "%sAlloc failures : %d\n", space, pool->event_alloc_failures);
516 }
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