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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Digital Audio (PCM) abstract layer
4 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5 */
6
7#include <linux/io.h>
8#include <linux/time.h>
9#include <linux/init.h>
10#include <linux/slab.h>
11#include <linux/moduleparam.h>
12#include <linux/vmalloc.h>
13#include <linux/export.h>
14#include <sound/core.h>
15#include <sound/pcm.h>
16#include <sound/info.h>
17#include <sound/initval.h>
18#include "pcm_local.h"
19
20static int preallocate_dma = 1;
21module_param(preallocate_dma, int, 0444);
22MODULE_PARM_DESC(preallocate_dma, "Preallocate DMA memory when the PCM devices are initialized.");
23
24static int maximum_substreams = 4;
25module_param(maximum_substreams, int, 0444);
26MODULE_PARM_DESC(maximum_substreams, "Maximum substreams with preallocated DMA memory.");
27
28static const size_t snd_minimum_buffer = 16384;
29
30static unsigned long max_alloc_per_card = 32UL * 1024UL * 1024UL;
31module_param(max_alloc_per_card, ulong, 0644);
32MODULE_PARM_DESC(max_alloc_per_card, "Max total allocation bytes per card.");
33
34static int do_alloc_pages(struct snd_card *card, int type, struct device *dev,
35 size_t size, struct snd_dma_buffer *dmab)
36{
37 int err;
38
39 if (max_alloc_per_card &&
40 card->total_pcm_alloc_bytes + size > max_alloc_per_card)
41 return -ENOMEM;
42
43 err = snd_dma_alloc_pages(type, dev, size, dmab);
44 if (!err) {
45 mutex_lock(&card->memory_mutex);
46 card->total_pcm_alloc_bytes += dmab->bytes;
47 mutex_unlock(&card->memory_mutex);
48 }
49 return err;
50}
51
52static void do_free_pages(struct snd_card *card, struct snd_dma_buffer *dmab)
53{
54 if (!dmab->area)
55 return;
56 mutex_lock(&card->memory_mutex);
57 WARN_ON(card->total_pcm_alloc_bytes < dmab->bytes);
58 card->total_pcm_alloc_bytes -= dmab->bytes;
59 mutex_unlock(&card->memory_mutex);
60 snd_dma_free_pages(dmab);
61 dmab->area = NULL;
62}
63
64/*
65 * try to allocate as the large pages as possible.
66 * stores the resultant memory size in *res_size.
67 *
68 * the minimum size is snd_minimum_buffer. it should be power of 2.
69 */
70static int preallocate_pcm_pages(struct snd_pcm_substream *substream, size_t size)
71{
72 struct snd_dma_buffer *dmab = &substream->dma_buffer;
73 struct snd_card *card = substream->pcm->card;
74 size_t orig_size = size;
75 int err;
76
77 do {
78 err = do_alloc_pages(card, dmab->dev.type, dmab->dev.dev,
79 size, dmab);
80 if (err != -ENOMEM)
81 return err;
82 size >>= 1;
83 } while (size >= snd_minimum_buffer);
84 dmab->bytes = 0; /* tell error */
85 pr_warn("ALSA pcmC%dD%d%c,%d:%s: cannot preallocate for size %zu\n",
86 substream->pcm->card->number, substream->pcm->device,
87 substream->stream ? 'c' : 'p', substream->number,
88 substream->pcm->name, orig_size);
89 return 0;
90}
91
92/*
93 * release the preallocated buffer if not yet done.
94 */
95static void snd_pcm_lib_preallocate_dma_free(struct snd_pcm_substream *substream)
96{
97 do_free_pages(substream->pcm->card, &substream->dma_buffer);
98}
99
100/**
101 * snd_pcm_lib_preallocate_free - release the preallocated buffer of the specified substream.
102 * @substream: the pcm substream instance
103 *
104 * Releases the pre-allocated buffer of the given substream.
105 */
106void snd_pcm_lib_preallocate_free(struct snd_pcm_substream *substream)
107{
108 snd_pcm_lib_preallocate_dma_free(substream);
109}
110
111/**
112 * snd_pcm_lib_preallocate_free_for_all - release all pre-allocated buffers on the pcm
113 * @pcm: the pcm instance
114 *
115 * Releases all the pre-allocated buffers on the given pcm.
116 */
117void snd_pcm_lib_preallocate_free_for_all(struct snd_pcm *pcm)
118{
119 struct snd_pcm_substream *substream;
120 int stream;
121
122 for (stream = 0; stream < 2; stream++)
123 for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
124 snd_pcm_lib_preallocate_free(substream);
125}
126EXPORT_SYMBOL(snd_pcm_lib_preallocate_free_for_all);
127
128#ifdef CONFIG_SND_VERBOSE_PROCFS
129/*
130 * read callback for prealloc proc file
131 *
132 * prints the current allocated size in kB.
133 */
134static void snd_pcm_lib_preallocate_proc_read(struct snd_info_entry *entry,
135 struct snd_info_buffer *buffer)
136{
137 struct snd_pcm_substream *substream = entry->private_data;
138 snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_buffer.bytes / 1024);
139}
140
141/*
142 * read callback for prealloc_max proc file
143 *
144 * prints the maximum allowed size in kB.
145 */
146static void snd_pcm_lib_preallocate_max_proc_read(struct snd_info_entry *entry,
147 struct snd_info_buffer *buffer)
148{
149 struct snd_pcm_substream *substream = entry->private_data;
150 snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_max / 1024);
151}
152
153/*
154 * write callback for prealloc proc file
155 *
156 * accepts the preallocation size in kB.
157 */
158static void snd_pcm_lib_preallocate_proc_write(struct snd_info_entry *entry,
159 struct snd_info_buffer *buffer)
160{
161 struct snd_pcm_substream *substream = entry->private_data;
162 struct snd_card *card = substream->pcm->card;
163 char line[64], str[64];
164 size_t size;
165 struct snd_dma_buffer new_dmab;
166
167 if (substream->runtime) {
168 buffer->error = -EBUSY;
169 return;
170 }
171 if (!snd_info_get_line(buffer, line, sizeof(line))) {
172 snd_info_get_str(str, line, sizeof(str));
173 size = simple_strtoul(str, NULL, 10) * 1024;
174 if ((size != 0 && size < 8192) || size > substream->dma_max) {
175 buffer->error = -EINVAL;
176 return;
177 }
178 if (substream->dma_buffer.bytes == size)
179 return;
180 memset(&new_dmab, 0, sizeof(new_dmab));
181 new_dmab.dev = substream->dma_buffer.dev;
182 if (size > 0) {
183 if (do_alloc_pages(card,
184 substream->dma_buffer.dev.type,
185 substream->dma_buffer.dev.dev,
186 size, &new_dmab) < 0) {
187 buffer->error = -ENOMEM;
188 return;
189 }
190 substream->buffer_bytes_max = size;
191 } else {
192 substream->buffer_bytes_max = UINT_MAX;
193 }
194 if (substream->dma_buffer.area)
195 do_free_pages(card, &substream->dma_buffer);
196 substream->dma_buffer = new_dmab;
197 } else {
198 buffer->error = -EINVAL;
199 }
200}
201
202static inline void preallocate_info_init(struct snd_pcm_substream *substream)
203{
204 struct snd_info_entry *entry;
205
206 entry = snd_info_create_card_entry(substream->pcm->card, "prealloc",
207 substream->proc_root);
208 if (entry) {
209 snd_info_set_text_ops(entry, substream,
210 snd_pcm_lib_preallocate_proc_read);
211 entry->c.text.write = snd_pcm_lib_preallocate_proc_write;
212 entry->mode |= 0200;
213 }
214 entry = snd_info_create_card_entry(substream->pcm->card, "prealloc_max",
215 substream->proc_root);
216 if (entry)
217 snd_info_set_text_ops(entry, substream,
218 snd_pcm_lib_preallocate_max_proc_read);
219}
220
221#else /* !CONFIG_SND_VERBOSE_PROCFS */
222#define preallocate_info_init(s)
223#endif /* CONFIG_SND_VERBOSE_PROCFS */
224
225/*
226 * pre-allocate the buffer and create a proc file for the substream
227 */
228static void preallocate_pages(struct snd_pcm_substream *substream,
229 int type, struct device *data,
230 size_t size, size_t max, bool managed)
231{
232 if (snd_BUG_ON(substream->dma_buffer.dev.type))
233 return;
234
235 substream->dma_buffer.dev.type = type;
236 substream->dma_buffer.dev.dev = data;
237
238 if (size > 0 && preallocate_dma && substream->number < maximum_substreams)
239 preallocate_pcm_pages(substream, size);
240
241 if (substream->dma_buffer.bytes > 0)
242 substream->buffer_bytes_max = substream->dma_buffer.bytes;
243 substream->dma_max = max;
244 if (max > 0)
245 preallocate_info_init(substream);
246 if (managed)
247 substream->managed_buffer_alloc = 1;
248}
249
250static void preallocate_pages_for_all(struct snd_pcm *pcm, int type,
251 void *data, size_t size, size_t max,
252 bool managed)
253{
254 struct snd_pcm_substream *substream;
255 int stream;
256
257 for (stream = 0; stream < 2; stream++)
258 for (substream = pcm->streams[stream].substream; substream;
259 substream = substream->next)
260 preallocate_pages(substream, type, data, size, max,
261 managed);
262}
263
264/**
265 * snd_pcm_lib_preallocate_pages - pre-allocation for the given DMA type
266 * @substream: the pcm substream instance
267 * @type: DMA type (SNDRV_DMA_TYPE_*)
268 * @data: DMA type dependent data
269 * @size: the requested pre-allocation size in bytes
270 * @max: the max. allowed pre-allocation size
271 *
272 * Do pre-allocation for the given DMA buffer type.
273 */
274void snd_pcm_lib_preallocate_pages(struct snd_pcm_substream *substream,
275 int type, struct device *data,
276 size_t size, size_t max)
277{
278 preallocate_pages(substream, type, data, size, max, false);
279}
280EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages);
281
282/**
283 * snd_pcm_lib_preallocate_pages_for_all - pre-allocation for continuous memory type (all substreams)
284 * @pcm: the pcm instance
285 * @type: DMA type (SNDRV_DMA_TYPE_*)
286 * @data: DMA type dependent data
287 * @size: the requested pre-allocation size in bytes
288 * @max: the max. allowed pre-allocation size
289 *
290 * Do pre-allocation to all substreams of the given pcm for the
291 * specified DMA type.
292 */
293void snd_pcm_lib_preallocate_pages_for_all(struct snd_pcm *pcm,
294 int type, void *data,
295 size_t size, size_t max)
296{
297 preallocate_pages_for_all(pcm, type, data, size, max, false);
298}
299EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages_for_all);
300
301/**
302 * snd_pcm_set_managed_buffer - set up buffer management for a substream
303 * @substream: the pcm substream instance
304 * @type: DMA type (SNDRV_DMA_TYPE_*)
305 * @data: DMA type dependent data
306 * @size: the requested pre-allocation size in bytes
307 * @max: the max. allowed pre-allocation size
308 *
309 * Do pre-allocation for the given DMA buffer type, and set the managed
310 * buffer allocation mode to the given substream.
311 * In this mode, PCM core will allocate a buffer automatically before PCM
312 * hw_params ops call, and release the buffer after PCM hw_free ops call
313 * as well, so that the driver doesn't need to invoke the allocation and
314 * the release explicitly in its callback.
315 * When a buffer is actually allocated before the PCM hw_params call, it
316 * turns on the runtime buffer_changed flag for drivers changing their h/w
317 * parameters accordingly.
318 */
319void snd_pcm_set_managed_buffer(struct snd_pcm_substream *substream, int type,
320 struct device *data, size_t size, size_t max)
321{
322 preallocate_pages(substream, type, data, size, max, true);
323}
324EXPORT_SYMBOL(snd_pcm_set_managed_buffer);
325
326/**
327 * snd_pcm_set_managed_buffer_all - set up buffer management for all substreams
328 * for all substreams
329 * @pcm: the pcm instance
330 * @type: DMA type (SNDRV_DMA_TYPE_*)
331 * @data: DMA type dependent data
332 * @size: the requested pre-allocation size in bytes
333 * @max: the max. allowed pre-allocation size
334 *
335 * Do pre-allocation to all substreams of the given pcm for the specified DMA
336 * type and size, and set the managed_buffer_alloc flag to each substream.
337 */
338void snd_pcm_set_managed_buffer_all(struct snd_pcm *pcm, int type,
339 struct device *data,
340 size_t size, size_t max)
341{
342 preallocate_pages_for_all(pcm, type, data, size, max, true);
343}
344EXPORT_SYMBOL(snd_pcm_set_managed_buffer_all);
345
346#ifdef CONFIG_SND_DMA_SGBUF
347/*
348 * snd_pcm_sgbuf_ops_page - get the page struct at the given offset
349 * @substream: the pcm substream instance
350 * @offset: the buffer offset
351 *
352 * Used as the page callback of PCM ops.
353 *
354 * Return: The page struct at the given buffer offset. %NULL on failure.
355 */
356struct page *snd_pcm_sgbuf_ops_page(struct snd_pcm_substream *substream, unsigned long offset)
357{
358 struct snd_sg_buf *sgbuf = snd_pcm_substream_sgbuf(substream);
359
360 unsigned int idx = offset >> PAGE_SHIFT;
361 if (idx >= (unsigned int)sgbuf->pages)
362 return NULL;
363 return sgbuf->page_table[idx];
364}
365#endif /* CONFIG_SND_DMA_SGBUF */
366
367/**
368 * snd_pcm_lib_malloc_pages - allocate the DMA buffer
369 * @substream: the substream to allocate the DMA buffer to
370 * @size: the requested buffer size in bytes
371 *
372 * Allocates the DMA buffer on the BUS type given earlier to
373 * snd_pcm_lib_preallocate_xxx_pages().
374 *
375 * Return: 1 if the buffer is changed, 0 if not changed, or a negative
376 * code on failure.
377 */
378int snd_pcm_lib_malloc_pages(struct snd_pcm_substream *substream, size_t size)
379{
380 struct snd_card *card = substream->pcm->card;
381 struct snd_pcm_runtime *runtime;
382 struct snd_dma_buffer *dmab = NULL;
383
384 if (PCM_RUNTIME_CHECK(substream))
385 return -EINVAL;
386 if (snd_BUG_ON(substream->dma_buffer.dev.type ==
387 SNDRV_DMA_TYPE_UNKNOWN))
388 return -EINVAL;
389 runtime = substream->runtime;
390
391 if (runtime->dma_buffer_p) {
392 /* perphaps, we might free the large DMA memory region
393 to save some space here, but the actual solution
394 costs us less time */
395 if (runtime->dma_buffer_p->bytes >= size) {
396 runtime->dma_bytes = size;
397 return 0; /* ok, do not change */
398 }
399 snd_pcm_lib_free_pages(substream);
400 }
401 if (substream->dma_buffer.area != NULL &&
402 substream->dma_buffer.bytes >= size) {
403 dmab = &substream->dma_buffer; /* use the pre-allocated buffer */
404 } else {
405 dmab = kzalloc(sizeof(*dmab), GFP_KERNEL);
406 if (! dmab)
407 return -ENOMEM;
408 dmab->dev = substream->dma_buffer.dev;
409 if (do_alloc_pages(card,
410 substream->dma_buffer.dev.type,
411 substream->dma_buffer.dev.dev,
412 size, dmab) < 0) {
413 kfree(dmab);
414 return -ENOMEM;
415 }
416 }
417 snd_pcm_set_runtime_buffer(substream, dmab);
418 runtime->dma_bytes = size;
419 return 1; /* area was changed */
420}
421EXPORT_SYMBOL(snd_pcm_lib_malloc_pages);
422
423/**
424 * snd_pcm_lib_free_pages - release the allocated DMA buffer.
425 * @substream: the substream to release the DMA buffer
426 *
427 * Releases the DMA buffer allocated via snd_pcm_lib_malloc_pages().
428 *
429 * Return: Zero if successful, or a negative error code on failure.
430 */
431int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream)
432{
433 struct snd_card *card = substream->pcm->card;
434 struct snd_pcm_runtime *runtime;
435
436 if (PCM_RUNTIME_CHECK(substream))
437 return -EINVAL;
438 runtime = substream->runtime;
439 if (runtime->dma_area == NULL)
440 return 0;
441 if (runtime->dma_buffer_p != &substream->dma_buffer) {
442 /* it's a newly allocated buffer. release it now. */
443 do_free_pages(card, runtime->dma_buffer_p);
444 kfree(runtime->dma_buffer_p);
445 }
446 snd_pcm_set_runtime_buffer(substream, NULL);
447 return 0;
448}
449EXPORT_SYMBOL(snd_pcm_lib_free_pages);
450
451int _snd_pcm_lib_alloc_vmalloc_buffer(struct snd_pcm_substream *substream,
452 size_t size, gfp_t gfp_flags)
453{
454 struct snd_pcm_runtime *runtime;
455
456 if (PCM_RUNTIME_CHECK(substream))
457 return -EINVAL;
458 runtime = substream->runtime;
459 if (runtime->dma_area) {
460 if (runtime->dma_bytes >= size)
461 return 0; /* already large enough */
462 vfree(runtime->dma_area);
463 }
464 runtime->dma_area = __vmalloc(size, gfp_flags);
465 if (!runtime->dma_area)
466 return -ENOMEM;
467 runtime->dma_bytes = size;
468 return 1;
469}
470EXPORT_SYMBOL(_snd_pcm_lib_alloc_vmalloc_buffer);
471
472/**
473 * snd_pcm_lib_free_vmalloc_buffer - free vmalloc buffer
474 * @substream: the substream with a buffer allocated by
475 * snd_pcm_lib_alloc_vmalloc_buffer()
476 *
477 * Return: Zero if successful, or a negative error code on failure.
478 */
479int snd_pcm_lib_free_vmalloc_buffer(struct snd_pcm_substream *substream)
480{
481 struct snd_pcm_runtime *runtime;
482
483 if (PCM_RUNTIME_CHECK(substream))
484 return -EINVAL;
485 runtime = substream->runtime;
486 vfree(runtime->dma_area);
487 runtime->dma_area = NULL;
488 return 0;
489}
490EXPORT_SYMBOL(snd_pcm_lib_free_vmalloc_buffer);
491
492/**
493 * snd_pcm_lib_get_vmalloc_page - map vmalloc buffer offset to page struct
494 * @substream: the substream with a buffer allocated by
495 * snd_pcm_lib_alloc_vmalloc_buffer()
496 * @offset: offset in the buffer
497 *
498 * This function is to be used as the page callback in the PCM ops.
499 *
500 * Return: The page struct, or %NULL on failure.
501 */
502struct page *snd_pcm_lib_get_vmalloc_page(struct snd_pcm_substream *substream,
503 unsigned long offset)
504{
505 return vmalloc_to_page(substream->runtime->dma_area + offset);
506}
507EXPORT_SYMBOL(snd_pcm_lib_get_vmalloc_page);
1/*
2 * Digital Audio (PCM) abstract layer
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 *
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 */
21
22#include <asm/io.h>
23#include <linux/time.h>
24#include <linux/init.h>
25#include <linux/slab.h>
26#include <linux/moduleparam.h>
27#include <linux/vmalloc.h>
28#include <sound/core.h>
29#include <sound/pcm.h>
30#include <sound/info.h>
31#include <sound/initval.h>
32
33static int preallocate_dma = 1;
34module_param(preallocate_dma, int, 0444);
35MODULE_PARM_DESC(preallocate_dma, "Preallocate DMA memory when the PCM devices are initialized.");
36
37static int maximum_substreams = 4;
38module_param(maximum_substreams, int, 0444);
39MODULE_PARM_DESC(maximum_substreams, "Maximum substreams with preallocated DMA memory.");
40
41static const size_t snd_minimum_buffer = 16384;
42
43
44/*
45 * try to allocate as the large pages as possible.
46 * stores the resultant memory size in *res_size.
47 *
48 * the minimum size is snd_minimum_buffer. it should be power of 2.
49 */
50static int preallocate_pcm_pages(struct snd_pcm_substream *substream, size_t size)
51{
52 struct snd_dma_buffer *dmab = &substream->dma_buffer;
53 int err;
54
55 /* already reserved? */
56 if (snd_dma_get_reserved_buf(dmab, substream->dma_buf_id) > 0) {
57 if (dmab->bytes >= size)
58 return 0; /* yes */
59 /* no, free the reserved block */
60 snd_dma_free_pages(dmab);
61 dmab->bytes = 0;
62 }
63
64 do {
65 if ((err = snd_dma_alloc_pages(dmab->dev.type, dmab->dev.dev,
66 size, dmab)) < 0) {
67 if (err != -ENOMEM)
68 return err; /* fatal error */
69 } else
70 return 0;
71 size >>= 1;
72 } while (size >= snd_minimum_buffer);
73 dmab->bytes = 0; /* tell error */
74 return 0;
75}
76
77/*
78 * release the preallocated buffer if not yet done.
79 */
80static void snd_pcm_lib_preallocate_dma_free(struct snd_pcm_substream *substream)
81{
82 if (substream->dma_buffer.area == NULL)
83 return;
84 if (substream->dma_buf_id)
85 snd_dma_reserve_buf(&substream->dma_buffer, substream->dma_buf_id);
86 else
87 snd_dma_free_pages(&substream->dma_buffer);
88 substream->dma_buffer.area = NULL;
89}
90
91/**
92 * snd_pcm_lib_preallocate_free - release the preallocated buffer of the specified substream.
93 * @substream: the pcm substream instance
94 *
95 * Releases the pre-allocated buffer of the given substream.
96 *
97 * Returns zero if successful, or a negative error code on failure.
98 */
99int snd_pcm_lib_preallocate_free(struct snd_pcm_substream *substream)
100{
101 snd_pcm_lib_preallocate_dma_free(substream);
102#ifdef CONFIG_SND_VERBOSE_PROCFS
103 snd_info_free_entry(substream->proc_prealloc_max_entry);
104 substream->proc_prealloc_max_entry = NULL;
105 snd_info_free_entry(substream->proc_prealloc_entry);
106 substream->proc_prealloc_entry = NULL;
107#endif
108 return 0;
109}
110
111/**
112 * snd_pcm_lib_preallocate_free_for_all - release all pre-allocated buffers on the pcm
113 * @pcm: the pcm instance
114 *
115 * Releases all the pre-allocated buffers on the given pcm.
116 *
117 * Returns zero if successful, or a negative error code on failure.
118 */
119int snd_pcm_lib_preallocate_free_for_all(struct snd_pcm *pcm)
120{
121 struct snd_pcm_substream *substream;
122 int stream;
123
124 for (stream = 0; stream < 2; stream++)
125 for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
126 snd_pcm_lib_preallocate_free(substream);
127 return 0;
128}
129
130EXPORT_SYMBOL(snd_pcm_lib_preallocate_free_for_all);
131
132#ifdef CONFIG_SND_VERBOSE_PROCFS
133/*
134 * read callback for prealloc proc file
135 *
136 * prints the current allocated size in kB.
137 */
138static void snd_pcm_lib_preallocate_proc_read(struct snd_info_entry *entry,
139 struct snd_info_buffer *buffer)
140{
141 struct snd_pcm_substream *substream = entry->private_data;
142 snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_buffer.bytes / 1024);
143}
144
145/*
146 * read callback for prealloc_max proc file
147 *
148 * prints the maximum allowed size in kB.
149 */
150static void snd_pcm_lib_preallocate_max_proc_read(struct snd_info_entry *entry,
151 struct snd_info_buffer *buffer)
152{
153 struct snd_pcm_substream *substream = entry->private_data;
154 snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_max / 1024);
155}
156
157/*
158 * write callback for prealloc proc file
159 *
160 * accepts the preallocation size in kB.
161 */
162static void snd_pcm_lib_preallocate_proc_write(struct snd_info_entry *entry,
163 struct snd_info_buffer *buffer)
164{
165 struct snd_pcm_substream *substream = entry->private_data;
166 char line[64], str[64];
167 size_t size;
168 struct snd_dma_buffer new_dmab;
169
170 if (substream->runtime) {
171 buffer->error = -EBUSY;
172 return;
173 }
174 if (!snd_info_get_line(buffer, line, sizeof(line))) {
175 snd_info_get_str(str, line, sizeof(str));
176 size = simple_strtoul(str, NULL, 10) * 1024;
177 if ((size != 0 && size < 8192) || size > substream->dma_max) {
178 buffer->error = -EINVAL;
179 return;
180 }
181 if (substream->dma_buffer.bytes == size)
182 return;
183 memset(&new_dmab, 0, sizeof(new_dmab));
184 new_dmab.dev = substream->dma_buffer.dev;
185 if (size > 0) {
186 if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
187 substream->dma_buffer.dev.dev,
188 size, &new_dmab) < 0) {
189 buffer->error = -ENOMEM;
190 return;
191 }
192 substream->buffer_bytes_max = size;
193 } else {
194 substream->buffer_bytes_max = UINT_MAX;
195 }
196 if (substream->dma_buffer.area)
197 snd_dma_free_pages(&substream->dma_buffer);
198 substream->dma_buffer = new_dmab;
199 } else {
200 buffer->error = -EINVAL;
201 }
202}
203
204static inline void preallocate_info_init(struct snd_pcm_substream *substream)
205{
206 struct snd_info_entry *entry;
207
208 if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc", substream->proc_root)) != NULL) {
209 entry->c.text.read = snd_pcm_lib_preallocate_proc_read;
210 entry->c.text.write = snd_pcm_lib_preallocate_proc_write;
211 entry->mode |= S_IWUSR;
212 entry->private_data = substream;
213 if (snd_info_register(entry) < 0) {
214 snd_info_free_entry(entry);
215 entry = NULL;
216 }
217 }
218 substream->proc_prealloc_entry = entry;
219 if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc_max", substream->proc_root)) != NULL) {
220 entry->c.text.read = snd_pcm_lib_preallocate_max_proc_read;
221 entry->private_data = substream;
222 if (snd_info_register(entry) < 0) {
223 snd_info_free_entry(entry);
224 entry = NULL;
225 }
226 }
227 substream->proc_prealloc_max_entry = entry;
228}
229
230#else /* !CONFIG_SND_VERBOSE_PROCFS */
231#define preallocate_info_init(s)
232#endif /* CONFIG_SND_VERBOSE_PROCFS */
233
234/*
235 * pre-allocate the buffer and create a proc file for the substream
236 */
237static int snd_pcm_lib_preallocate_pages1(struct snd_pcm_substream *substream,
238 size_t size, size_t max)
239{
240
241 if (size > 0 && preallocate_dma && substream->number < maximum_substreams)
242 preallocate_pcm_pages(substream, size);
243
244 if (substream->dma_buffer.bytes > 0)
245 substream->buffer_bytes_max = substream->dma_buffer.bytes;
246 substream->dma_max = max;
247 preallocate_info_init(substream);
248 return 0;
249}
250
251
252/**
253 * snd_pcm_lib_preallocate_pages - pre-allocation for the given DMA type
254 * @substream: the pcm substream instance
255 * @type: DMA type (SNDRV_DMA_TYPE_*)
256 * @data: DMA type dependent data
257 * @size: the requested pre-allocation size in bytes
258 * @max: the max. allowed pre-allocation size
259 *
260 * Do pre-allocation for the given DMA buffer type.
261 *
262 * When substream->dma_buf_id is set, the function tries to look for
263 * the reserved buffer, and the buffer is not freed but reserved at
264 * destruction time. The dma_buf_id must be unique for all systems
265 * (in the same DMA buffer type) e.g. using snd_dma_pci_buf_id().
266 *
267 * Returns zero if successful, or a negative error code on failure.
268 */
269int snd_pcm_lib_preallocate_pages(struct snd_pcm_substream *substream,
270 int type, struct device *data,
271 size_t size, size_t max)
272{
273 substream->dma_buffer.dev.type = type;
274 substream->dma_buffer.dev.dev = data;
275 return snd_pcm_lib_preallocate_pages1(substream, size, max);
276}
277
278EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages);
279
280/**
281 * snd_pcm_lib_preallocate_pages_for_all - pre-allocation for continuous memory type (all substreams)
282 * @pcm: the pcm instance
283 * @type: DMA type (SNDRV_DMA_TYPE_*)
284 * @data: DMA type dependent data
285 * @size: the requested pre-allocation size in bytes
286 * @max: the max. allowed pre-allocation size
287 *
288 * Do pre-allocation to all substreams of the given pcm for the
289 * specified DMA type.
290 *
291 * Returns zero if successful, or a negative error code on failure.
292 */
293int snd_pcm_lib_preallocate_pages_for_all(struct snd_pcm *pcm,
294 int type, void *data,
295 size_t size, size_t max)
296{
297 struct snd_pcm_substream *substream;
298 int stream, err;
299
300 for (stream = 0; stream < 2; stream++)
301 for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
302 if ((err = snd_pcm_lib_preallocate_pages(substream, type, data, size, max)) < 0)
303 return err;
304 return 0;
305}
306
307EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages_for_all);
308
309#ifdef CONFIG_SND_DMA_SGBUF
310/**
311 * snd_pcm_sgbuf_ops_page - get the page struct at the given offset
312 * @substream: the pcm substream instance
313 * @offset: the buffer offset
314 *
315 * Returns the page struct at the given buffer offset.
316 * Used as the page callback of PCM ops.
317 */
318struct page *snd_pcm_sgbuf_ops_page(struct snd_pcm_substream *substream, unsigned long offset)
319{
320 struct snd_sg_buf *sgbuf = snd_pcm_substream_sgbuf(substream);
321
322 unsigned int idx = offset >> PAGE_SHIFT;
323 if (idx >= (unsigned int)sgbuf->pages)
324 return NULL;
325 return sgbuf->page_table[idx];
326}
327
328EXPORT_SYMBOL(snd_pcm_sgbuf_ops_page);
329
330/*
331 * compute the max chunk size with continuous pages on sg-buffer
332 */
333unsigned int snd_pcm_sgbuf_get_chunk_size(struct snd_pcm_substream *substream,
334 unsigned int ofs, unsigned int size)
335{
336 struct snd_sg_buf *sg = snd_pcm_substream_sgbuf(substream);
337 unsigned int start, end, pg;
338
339 start = ofs >> PAGE_SHIFT;
340 end = (ofs + size - 1) >> PAGE_SHIFT;
341 /* check page continuity */
342 pg = sg->table[start].addr >> PAGE_SHIFT;
343 for (;;) {
344 start++;
345 if (start > end)
346 break;
347 pg++;
348 if ((sg->table[start].addr >> PAGE_SHIFT) != pg)
349 return (start << PAGE_SHIFT) - ofs;
350 }
351 /* ok, all on continuous pages */
352 return size;
353}
354EXPORT_SYMBOL(snd_pcm_sgbuf_get_chunk_size);
355#endif /* CONFIG_SND_DMA_SGBUF */
356
357/**
358 * snd_pcm_lib_malloc_pages - allocate the DMA buffer
359 * @substream: the substream to allocate the DMA buffer to
360 * @size: the requested buffer size in bytes
361 *
362 * Allocates the DMA buffer on the BUS type given earlier to
363 * snd_pcm_lib_preallocate_xxx_pages().
364 *
365 * Returns 1 if the buffer is changed, 0 if not changed, or a negative
366 * code on failure.
367 */
368int snd_pcm_lib_malloc_pages(struct snd_pcm_substream *substream, size_t size)
369{
370 struct snd_pcm_runtime *runtime;
371 struct snd_dma_buffer *dmab = NULL;
372
373 if (PCM_RUNTIME_CHECK(substream))
374 return -EINVAL;
375 if (snd_BUG_ON(substream->dma_buffer.dev.type ==
376 SNDRV_DMA_TYPE_UNKNOWN))
377 return -EINVAL;
378 runtime = substream->runtime;
379
380 if (runtime->dma_buffer_p) {
381 /* perphaps, we might free the large DMA memory region
382 to save some space here, but the actual solution
383 costs us less time */
384 if (runtime->dma_buffer_p->bytes >= size) {
385 runtime->dma_bytes = size;
386 return 0; /* ok, do not change */
387 }
388 snd_pcm_lib_free_pages(substream);
389 }
390 if (substream->dma_buffer.area != NULL &&
391 substream->dma_buffer.bytes >= size) {
392 dmab = &substream->dma_buffer; /* use the pre-allocated buffer */
393 } else {
394 dmab = kzalloc(sizeof(*dmab), GFP_KERNEL);
395 if (! dmab)
396 return -ENOMEM;
397 dmab->dev = substream->dma_buffer.dev;
398 if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
399 substream->dma_buffer.dev.dev,
400 size, dmab) < 0) {
401 kfree(dmab);
402 return -ENOMEM;
403 }
404 }
405 snd_pcm_set_runtime_buffer(substream, dmab);
406 runtime->dma_bytes = size;
407 return 1; /* area was changed */
408}
409
410EXPORT_SYMBOL(snd_pcm_lib_malloc_pages);
411
412/**
413 * snd_pcm_lib_free_pages - release the allocated DMA buffer.
414 * @substream: the substream to release the DMA buffer
415 *
416 * Releases the DMA buffer allocated via snd_pcm_lib_malloc_pages().
417 *
418 * Returns zero if successful, or a negative error code on failure.
419 */
420int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream)
421{
422 struct snd_pcm_runtime *runtime;
423
424 if (PCM_RUNTIME_CHECK(substream))
425 return -EINVAL;
426 runtime = substream->runtime;
427 if (runtime->dma_area == NULL)
428 return 0;
429 if (runtime->dma_buffer_p != &substream->dma_buffer) {
430 /* it's a newly allocated buffer. release it now. */
431 snd_dma_free_pages(runtime->dma_buffer_p);
432 kfree(runtime->dma_buffer_p);
433 }
434 snd_pcm_set_runtime_buffer(substream, NULL);
435 return 0;
436}
437
438EXPORT_SYMBOL(snd_pcm_lib_free_pages);
439
440int _snd_pcm_lib_alloc_vmalloc_buffer(struct snd_pcm_substream *substream,
441 size_t size, gfp_t gfp_flags)
442{
443 struct snd_pcm_runtime *runtime;
444
445 if (PCM_RUNTIME_CHECK(substream))
446 return -EINVAL;
447 runtime = substream->runtime;
448 if (runtime->dma_area) {
449 if (runtime->dma_bytes >= size)
450 return 0; /* already large enough */
451 vfree(runtime->dma_area);
452 }
453 runtime->dma_area = __vmalloc(size, gfp_flags, PAGE_KERNEL);
454 if (!runtime->dma_area)
455 return -ENOMEM;
456 runtime->dma_bytes = size;
457 return 1;
458}
459EXPORT_SYMBOL(_snd_pcm_lib_alloc_vmalloc_buffer);
460
461/**
462 * snd_pcm_lib_free_vmalloc_buffer - free vmalloc buffer
463 * @substream: the substream with a buffer allocated by
464 * snd_pcm_lib_alloc_vmalloc_buffer()
465 */
466int snd_pcm_lib_free_vmalloc_buffer(struct snd_pcm_substream *substream)
467{
468 struct snd_pcm_runtime *runtime;
469
470 if (PCM_RUNTIME_CHECK(substream))
471 return -EINVAL;
472 runtime = substream->runtime;
473 vfree(runtime->dma_area);
474 runtime->dma_area = NULL;
475 return 0;
476}
477EXPORT_SYMBOL(snd_pcm_lib_free_vmalloc_buffer);
478
479/**
480 * snd_pcm_lib_get_vmalloc_page - map vmalloc buffer offset to page struct
481 * @substream: the substream with a buffer allocated by
482 * snd_pcm_lib_alloc_vmalloc_buffer()
483 * @offset: offset in the buffer
484 *
485 * This function is to be used as the page callback in the PCM ops.
486 */
487struct page *snd_pcm_lib_get_vmalloc_page(struct snd_pcm_substream *substream,
488 unsigned long offset)
489{
490 return vmalloc_to_page(substream->runtime->dma_area + offset);
491}
492EXPORT_SYMBOL(snd_pcm_lib_get_vmalloc_page);