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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);
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 int str, size_t size, struct snd_dma_buffer *dmab)
36{
37 enum dma_data_direction dir;
38 int err;
39
40 if (max_alloc_per_card &&
41 card->total_pcm_alloc_bytes + size > max_alloc_per_card)
42 return -ENOMEM;
43
44 if (str == SNDRV_PCM_STREAM_PLAYBACK)
45 dir = DMA_TO_DEVICE;
46 else
47 dir = DMA_FROM_DEVICE;
48 err = snd_dma_alloc_dir_pages(type, dev, dir, size, dmab);
49 if (!err) {
50 mutex_lock(&card->memory_mutex);
51 card->total_pcm_alloc_bytes += dmab->bytes;
52 mutex_unlock(&card->memory_mutex);
53 }
54 return err;
55}
56
57static void do_free_pages(struct snd_card *card, struct snd_dma_buffer *dmab)
58{
59 if (!dmab->area)
60 return;
61 mutex_lock(&card->memory_mutex);
62 WARN_ON(card->total_pcm_alloc_bytes < dmab->bytes);
63 card->total_pcm_alloc_bytes -= dmab->bytes;
64 mutex_unlock(&card->memory_mutex);
65 snd_dma_free_pages(dmab);
66 dmab->area = NULL;
67}
68
69/*
70 * try to allocate as the large pages as possible.
71 * stores the resultant memory size in *res_size.
72 *
73 * the minimum size is snd_minimum_buffer. it should be power of 2.
74 */
75static int preallocate_pcm_pages(struct snd_pcm_substream *substream,
76 size_t size, bool no_fallback)
77{
78 struct snd_dma_buffer *dmab = &substream->dma_buffer;
79 struct snd_card *card = substream->pcm->card;
80 size_t orig_size = size;
81 int err;
82
83 do {
84 err = do_alloc_pages(card, dmab->dev.type, dmab->dev.dev,
85 substream->stream, size, dmab);
86 if (err != -ENOMEM)
87 return err;
88 if (no_fallback)
89 break;
90 size >>= 1;
91 } while (size >= snd_minimum_buffer);
92 dmab->bytes = 0; /* tell error */
93 pr_warn("ALSA pcmC%dD%d%c,%d:%s: cannot preallocate for size %zu\n",
94 substream->pcm->card->number, substream->pcm->device,
95 substream->stream ? 'c' : 'p', substream->number,
96 substream->pcm->name, orig_size);
97 return -ENOMEM;
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 do_free_pages(substream->pcm->card, &substream->dma_buffer);
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_each_pcm_substream(pcm, stream, substream)
123 snd_pcm_lib_preallocate_free(substream);
124}
125EXPORT_SYMBOL(snd_pcm_lib_preallocate_free_for_all);
126
127#ifdef CONFIG_SND_VERBOSE_PROCFS
128/*
129 * read callback for prealloc proc file
130 *
131 * prints the current allocated size in kB.
132 */
133static void snd_pcm_lib_preallocate_proc_read(struct snd_info_entry *entry,
134 struct snd_info_buffer *buffer)
135{
136 struct snd_pcm_substream *substream = entry->private_data;
137 snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_buffer.bytes / 1024);
138}
139
140/*
141 * read callback for prealloc_max proc file
142 *
143 * prints the maximum allowed size in kB.
144 */
145static void snd_pcm_lib_preallocate_max_proc_read(struct snd_info_entry *entry,
146 struct snd_info_buffer *buffer)
147{
148 struct snd_pcm_substream *substream = entry->private_data;
149 snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_max / 1024);
150}
151
152/*
153 * write callback for prealloc proc file
154 *
155 * accepts the preallocation size in kB.
156 */
157static void snd_pcm_lib_preallocate_proc_write(struct snd_info_entry *entry,
158 struct snd_info_buffer *buffer)
159{
160 struct snd_pcm_substream *substream = entry->private_data;
161 struct snd_card *card = substream->pcm->card;
162 char line[64], str[64];
163 size_t size;
164 struct snd_dma_buffer new_dmab;
165
166 mutex_lock(&substream->pcm->open_mutex);
167 if (substream->runtime) {
168 buffer->error = -EBUSY;
169 goto unlock;
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 goto unlock;
177 }
178 if (substream->dma_buffer.bytes == size)
179 goto unlock;
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 substream->stream,
187 size, &new_dmab) < 0) {
188 buffer->error = -ENOMEM;
189 pr_debug("ALSA pcmC%dD%d%c,%d:%s: cannot preallocate for size %zu\n",
190 substream->pcm->card->number, substream->pcm->device,
191 substream->stream ? 'c' : 'p', substream->number,
192 substream->pcm->name, size);
193 goto unlock;
194 }
195 substream->buffer_bytes_max = size;
196 } else {
197 substream->buffer_bytes_max = UINT_MAX;
198 }
199 if (substream->dma_buffer.area)
200 do_free_pages(card, &substream->dma_buffer);
201 substream->dma_buffer = new_dmab;
202 } else {
203 buffer->error = -EINVAL;
204 }
205 unlock:
206 mutex_unlock(&substream->pcm->open_mutex);
207}
208
209static inline void preallocate_info_init(struct snd_pcm_substream *substream)
210{
211 struct snd_info_entry *entry;
212
213 entry = snd_info_create_card_entry(substream->pcm->card, "prealloc",
214 substream->proc_root);
215 if (entry) {
216 snd_info_set_text_ops(entry, substream,
217 snd_pcm_lib_preallocate_proc_read);
218 entry->c.text.write = snd_pcm_lib_preallocate_proc_write;
219 entry->mode |= 0200;
220 }
221 entry = snd_info_create_card_entry(substream->pcm->card, "prealloc_max",
222 substream->proc_root);
223 if (entry)
224 snd_info_set_text_ops(entry, substream,
225 snd_pcm_lib_preallocate_max_proc_read);
226}
227
228#else /* !CONFIG_SND_VERBOSE_PROCFS */
229static inline void preallocate_info_init(struct snd_pcm_substream *substream)
230{
231}
232#endif /* CONFIG_SND_VERBOSE_PROCFS */
233
234/*
235 * pre-allocate the buffer and create a proc file for the substream
236 */
237static int preallocate_pages(struct snd_pcm_substream *substream,
238 int type, struct device *data,
239 size_t size, size_t max, bool managed)
240{
241 int err;
242
243 if (snd_BUG_ON(substream->dma_buffer.dev.type))
244 return -EINVAL;
245
246 substream->dma_buffer.dev.type = type;
247 substream->dma_buffer.dev.dev = data;
248
249 if (size > 0) {
250 if (!max) {
251 /* no fallback, only also inform -ENOMEM */
252 err = preallocate_pcm_pages(substream, size, true);
253 if (err < 0)
254 return err;
255 } else if (preallocate_dma &&
256 substream->number < maximum_substreams) {
257 err = preallocate_pcm_pages(substream, size, false);
258 if (err < 0 && err != -ENOMEM)
259 return err;
260 }
261 }
262
263 if (substream->dma_buffer.bytes > 0)
264 substream->buffer_bytes_max = substream->dma_buffer.bytes;
265 substream->dma_max = max;
266 if (max > 0)
267 preallocate_info_init(substream);
268 if (managed)
269 substream->managed_buffer_alloc = 1;
270 return 0;
271}
272
273static int preallocate_pages_for_all(struct snd_pcm *pcm, int type,
274 void *data, size_t size, size_t max,
275 bool managed)
276{
277 struct snd_pcm_substream *substream;
278 int stream, err;
279
280 for_each_pcm_substream(pcm, stream, substream) {
281 err = preallocate_pages(substream, type, data, size, max, managed);
282 if (err < 0)
283 return err;
284 }
285 return 0;
286}
287
288/**
289 * snd_pcm_lib_preallocate_pages - pre-allocation for the given DMA type
290 * @substream: the pcm substream instance
291 * @type: DMA type (SNDRV_DMA_TYPE_*)
292 * @data: DMA type dependent data
293 * @size: the requested pre-allocation size in bytes
294 * @max: the max. allowed pre-allocation size
295 *
296 * Do pre-allocation for the given DMA buffer type.
297 */
298void snd_pcm_lib_preallocate_pages(struct snd_pcm_substream *substream,
299 int type, struct device *data,
300 size_t size, size_t max)
301{
302 preallocate_pages(substream, type, data, size, max, false);
303}
304EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages);
305
306/**
307 * snd_pcm_lib_preallocate_pages_for_all - pre-allocation for continuous memory type (all substreams)
308 * @pcm: the pcm instance
309 * @type: DMA type (SNDRV_DMA_TYPE_*)
310 * @data: DMA type dependent data
311 * @size: the requested pre-allocation size in bytes
312 * @max: the max. allowed pre-allocation size
313 *
314 * Do pre-allocation to all substreams of the given pcm for the
315 * specified DMA type.
316 */
317void snd_pcm_lib_preallocate_pages_for_all(struct snd_pcm *pcm,
318 int type, void *data,
319 size_t size, size_t max)
320{
321 preallocate_pages_for_all(pcm, type, data, size, max, false);
322}
323EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages_for_all);
324
325/**
326 * snd_pcm_set_managed_buffer - set up buffer management for a substream
327 * @substream: the pcm substream instance
328 * @type: DMA type (SNDRV_DMA_TYPE_*)
329 * @data: DMA type dependent data
330 * @size: the requested pre-allocation size in bytes
331 * @max: the max. allowed pre-allocation size
332 *
333 * Do pre-allocation for the given DMA buffer type, and set the managed
334 * buffer allocation mode to the given substream.
335 * In this mode, PCM core will allocate a buffer automatically before PCM
336 * hw_params ops call, and release the buffer after PCM hw_free ops call
337 * as well, so that the driver doesn't need to invoke the allocation and
338 * the release explicitly in its callback.
339 * When a buffer is actually allocated before the PCM hw_params call, it
340 * turns on the runtime buffer_changed flag for drivers changing their h/w
341 * parameters accordingly.
342 *
343 * When @size is non-zero and @max is zero, this tries to allocate for only
344 * the exact buffer size without fallback, and may return -ENOMEM.
345 * Otherwise, the function tries to allocate smaller chunks if the allocation
346 * fails. This is the behavior of snd_pcm_set_fixed_buffer().
347 *
348 * When both @size and @max are zero, the function only sets up the buffer
349 * for later dynamic allocations. It's used typically for buffers with
350 * SNDRV_DMA_TYPE_VMALLOC type.
351 *
352 * Upon successful buffer allocation and setup, the function returns 0.
353 *
354 * Return: zero if successful, or a negative error code
355 */
356int snd_pcm_set_managed_buffer(struct snd_pcm_substream *substream, int type,
357 struct device *data, size_t size, size_t max)
358{
359 return preallocate_pages(substream, type, data, size, max, true);
360}
361EXPORT_SYMBOL(snd_pcm_set_managed_buffer);
362
363/**
364 * snd_pcm_set_managed_buffer_all - set up buffer management for all substreams
365 * for all substreams
366 * @pcm: the pcm instance
367 * @type: DMA type (SNDRV_DMA_TYPE_*)
368 * @data: DMA type dependent data
369 * @size: the requested pre-allocation size in bytes
370 * @max: the max. allowed pre-allocation size
371 *
372 * Do pre-allocation to all substreams of the given pcm for the specified DMA
373 * type and size, and set the managed_buffer_alloc flag to each substream.
374 *
375 * Return: zero if successful, or a negative error code
376 */
377int snd_pcm_set_managed_buffer_all(struct snd_pcm *pcm, int type,
378 struct device *data,
379 size_t size, size_t max)
380{
381 return preallocate_pages_for_all(pcm, type, data, size, max, true);
382}
383EXPORT_SYMBOL(snd_pcm_set_managed_buffer_all);
384
385/**
386 * snd_pcm_lib_malloc_pages - allocate the DMA buffer
387 * @substream: the substream to allocate the DMA buffer to
388 * @size: the requested buffer size in bytes
389 *
390 * Allocates the DMA buffer on the BUS type given earlier to
391 * snd_pcm_lib_preallocate_xxx_pages().
392 *
393 * Return: 1 if the buffer is changed, 0 if not changed, or a negative
394 * code on failure.
395 */
396int snd_pcm_lib_malloc_pages(struct snd_pcm_substream *substream, size_t size)
397{
398 struct snd_card *card;
399 struct snd_pcm_runtime *runtime;
400 struct snd_dma_buffer *dmab = NULL;
401
402 if (PCM_RUNTIME_CHECK(substream))
403 return -EINVAL;
404 if (snd_BUG_ON(substream->dma_buffer.dev.type ==
405 SNDRV_DMA_TYPE_UNKNOWN))
406 return -EINVAL;
407 runtime = substream->runtime;
408 card = substream->pcm->card;
409
410 if (runtime->dma_buffer_p) {
411 /* perphaps, we might free the large DMA memory region
412 to save some space here, but the actual solution
413 costs us less time */
414 if (runtime->dma_buffer_p->bytes >= size) {
415 runtime->dma_bytes = size;
416 return 0; /* ok, do not change */
417 }
418 snd_pcm_lib_free_pages(substream);
419 }
420 if (substream->dma_buffer.area != NULL &&
421 substream->dma_buffer.bytes >= size) {
422 dmab = &substream->dma_buffer; /* use the pre-allocated buffer */
423 } else {
424 /* dma_max=0 means the fixed size preallocation */
425 if (substream->dma_buffer.area && !substream->dma_max)
426 return -ENOMEM;
427 dmab = kzalloc(sizeof(*dmab), GFP_KERNEL);
428 if (! dmab)
429 return -ENOMEM;
430 dmab->dev = substream->dma_buffer.dev;
431 if (do_alloc_pages(card,
432 substream->dma_buffer.dev.type,
433 substream->dma_buffer.dev.dev,
434 substream->stream,
435 size, dmab) < 0) {
436 kfree(dmab);
437 pr_debug("ALSA pcmC%dD%d%c,%d:%s: cannot preallocate for size %zu\n",
438 substream->pcm->card->number, substream->pcm->device,
439 substream->stream ? 'c' : 'p', substream->number,
440 substream->pcm->name, size);
441 return -ENOMEM;
442 }
443 }
444 snd_pcm_set_runtime_buffer(substream, dmab);
445 runtime->dma_bytes = size;
446 return 1; /* area was changed */
447}
448EXPORT_SYMBOL(snd_pcm_lib_malloc_pages);
449
450/**
451 * snd_pcm_lib_free_pages - release the allocated DMA buffer.
452 * @substream: the substream to release the DMA buffer
453 *
454 * Releases the DMA buffer allocated via snd_pcm_lib_malloc_pages().
455 *
456 * Return: Zero if successful, or a negative error code on failure.
457 */
458int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream)
459{
460 struct snd_pcm_runtime *runtime;
461
462 if (PCM_RUNTIME_CHECK(substream))
463 return -EINVAL;
464 runtime = substream->runtime;
465 if (runtime->dma_area == NULL)
466 return 0;
467 if (runtime->dma_buffer_p != &substream->dma_buffer) {
468 struct snd_card *card = substream->pcm->card;
469
470 /* it's a newly allocated buffer. release it now. */
471 do_free_pages(card, runtime->dma_buffer_p);
472 kfree(runtime->dma_buffer_p);
473 }
474 snd_pcm_set_runtime_buffer(substream, NULL);
475 return 0;
476}
477EXPORT_SYMBOL(snd_pcm_lib_free_pages);
478
479int _snd_pcm_lib_alloc_vmalloc_buffer(struct snd_pcm_substream *substream,
480 size_t size, gfp_t gfp_flags)
481{
482 struct snd_pcm_runtime *runtime;
483
484 if (PCM_RUNTIME_CHECK(substream))
485 return -EINVAL;
486 runtime = substream->runtime;
487 if (runtime->dma_area) {
488 if (runtime->dma_bytes >= size)
489 return 0; /* already large enough */
490 vfree(runtime->dma_area);
491 }
492 runtime->dma_area = __vmalloc(size, gfp_flags);
493 if (!runtime->dma_area)
494 return -ENOMEM;
495 runtime->dma_bytes = size;
496 return 1;
497}
498EXPORT_SYMBOL(_snd_pcm_lib_alloc_vmalloc_buffer);
499
500/**
501 * snd_pcm_lib_free_vmalloc_buffer - free vmalloc buffer
502 * @substream: the substream with a buffer allocated by
503 * snd_pcm_lib_alloc_vmalloc_buffer()
504 *
505 * Return: Zero if successful, or a negative error code on failure.
506 */
507int snd_pcm_lib_free_vmalloc_buffer(struct snd_pcm_substream *substream)
508{
509 struct snd_pcm_runtime *runtime;
510
511 if (PCM_RUNTIME_CHECK(substream))
512 return -EINVAL;
513 runtime = substream->runtime;
514 vfree(runtime->dma_area);
515 runtime->dma_area = NULL;
516 return 0;
517}
518EXPORT_SYMBOL(snd_pcm_lib_free_vmalloc_buffer);
519
520/**
521 * snd_pcm_lib_get_vmalloc_page - map vmalloc buffer offset to page struct
522 * @substream: the substream with a buffer allocated by
523 * snd_pcm_lib_alloc_vmalloc_buffer()
524 * @offset: offset in the buffer
525 *
526 * This function is to be used as the page callback in the PCM ops.
527 *
528 * Return: The page struct, or %NULL on failure.
529 */
530struct page *snd_pcm_lib_get_vmalloc_page(struct snd_pcm_substream *substream,
531 unsigned long offset)
532{
533 return vmalloc_to_page(substream->runtime->dma_area + offset);
534}
535EXPORT_SYMBOL(snd_pcm_lib_get_vmalloc_page);