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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/*
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 <linux/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 <linux/export.h>
29#include <sound/core.h>
30#include <sound/pcm.h>
31#include <sound/info.h>
32#include <sound/initval.h>
33
34static int preallocate_dma = 1;
35module_param(preallocate_dma, int, 0444);
36MODULE_PARM_DESC(preallocate_dma, "Preallocate DMA memory when the PCM devices are initialized.");
37
38static int maximum_substreams = 4;
39module_param(maximum_substreams, int, 0444);
40MODULE_PARM_DESC(maximum_substreams, "Maximum substreams with preallocated DMA memory.");
41
42static const size_t snd_minimum_buffer = 16384;
43
44
45/*
46 * try to allocate as the large pages as possible.
47 * stores the resultant memory size in *res_size.
48 *
49 * the minimum size is snd_minimum_buffer. it should be power of 2.
50 */
51static int preallocate_pcm_pages(struct snd_pcm_substream *substream, size_t size)
52{
53 struct snd_dma_buffer *dmab = &substream->dma_buffer;
54 size_t orig_size = size;
55 int err;
56
57 do {
58 if ((err = snd_dma_alloc_pages(dmab->dev.type, dmab->dev.dev,
59 size, dmab)) < 0) {
60 if (err != -ENOMEM)
61 return err; /* fatal error */
62 } else
63 return 0;
64 size >>= 1;
65 } while (size >= snd_minimum_buffer);
66 dmab->bytes = 0; /* tell error */
67 pr_warn("ALSA pcmC%dD%d%c,%d:%s: cannot preallocate for size %zu\n",
68 substream->pcm->card->number, substream->pcm->device,
69 substream->stream ? 'c' : 'p', substream->number,
70 substream->pcm->name, orig_size);
71 return 0;
72}
73
74/*
75 * release the preallocated buffer if not yet done.
76 */
77static void snd_pcm_lib_preallocate_dma_free(struct snd_pcm_substream *substream)
78{
79 if (substream->dma_buffer.area == NULL)
80 return;
81 snd_dma_free_pages(&substream->dma_buffer);
82 substream->dma_buffer.area = NULL;
83}
84
85/**
86 * snd_pcm_lib_preallocate_free - release the preallocated buffer of the specified substream.
87 * @substream: the pcm substream instance
88 *
89 * Releases the pre-allocated buffer of the given substream.
90 *
91 * Return: Zero if successful, or a negative error code on failure.
92 */
93int snd_pcm_lib_preallocate_free(struct snd_pcm_substream *substream)
94{
95 snd_pcm_lib_preallocate_dma_free(substream);
96#ifdef CONFIG_SND_VERBOSE_PROCFS
97 snd_info_free_entry(substream->proc_prealloc_max_entry);
98 substream->proc_prealloc_max_entry = NULL;
99 snd_info_free_entry(substream->proc_prealloc_entry);
100 substream->proc_prealloc_entry = NULL;
101#endif
102 return 0;
103}
104
105/**
106 * snd_pcm_lib_preallocate_free_for_all - release all pre-allocated buffers on the pcm
107 * @pcm: the pcm instance
108 *
109 * Releases all the pre-allocated buffers on the given pcm.
110 *
111 * Return: Zero if successful, or a negative error code on failure.
112 */
113int snd_pcm_lib_preallocate_free_for_all(struct snd_pcm *pcm)
114{
115 struct snd_pcm_substream *substream;
116 int stream;
117
118 for (stream = 0; stream < 2; stream++)
119 for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
120 snd_pcm_lib_preallocate_free(substream);
121 return 0;
122}
123
124EXPORT_SYMBOL(snd_pcm_lib_preallocate_free_for_all);
125
126#ifdef CONFIG_SND_VERBOSE_PROCFS
127/*
128 * read callback for prealloc proc file
129 *
130 * prints the current allocated size in kB.
131 */
132static void snd_pcm_lib_preallocate_proc_read(struct snd_info_entry *entry,
133 struct snd_info_buffer *buffer)
134{
135 struct snd_pcm_substream *substream = entry->private_data;
136 snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_buffer.bytes / 1024);
137}
138
139/*
140 * read callback for prealloc_max proc file
141 *
142 * prints the maximum allowed size in kB.
143 */
144static void snd_pcm_lib_preallocate_max_proc_read(struct snd_info_entry *entry,
145 struct snd_info_buffer *buffer)
146{
147 struct snd_pcm_substream *substream = entry->private_data;
148 snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_max / 1024);
149}
150
151/*
152 * write callback for prealloc proc file
153 *
154 * accepts the preallocation size in kB.
155 */
156static void snd_pcm_lib_preallocate_proc_write(struct snd_info_entry *entry,
157 struct snd_info_buffer *buffer)
158{
159 struct snd_pcm_substream *substream = entry->private_data;
160 char line[64], str[64];
161 size_t size;
162 struct snd_dma_buffer new_dmab;
163
164 if (substream->runtime) {
165 buffer->error = -EBUSY;
166 return;
167 }
168 if (!snd_info_get_line(buffer, line, sizeof(line))) {
169 snd_info_get_str(str, line, sizeof(str));
170 size = simple_strtoul(str, NULL, 10) * 1024;
171 if ((size != 0 && size < 8192) || size > substream->dma_max) {
172 buffer->error = -EINVAL;
173 return;
174 }
175 if (substream->dma_buffer.bytes == size)
176 return;
177 memset(&new_dmab, 0, sizeof(new_dmab));
178 new_dmab.dev = substream->dma_buffer.dev;
179 if (size > 0) {
180 if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
181 substream->dma_buffer.dev.dev,
182 size, &new_dmab) < 0) {
183 buffer->error = -ENOMEM;
184 return;
185 }
186 substream->buffer_bytes_max = size;
187 } else {
188 substream->buffer_bytes_max = UINT_MAX;
189 }
190 if (substream->dma_buffer.area)
191 snd_dma_free_pages(&substream->dma_buffer);
192 substream->dma_buffer = new_dmab;
193 } else {
194 buffer->error = -EINVAL;
195 }
196}
197
198static inline void preallocate_info_init(struct snd_pcm_substream *substream)
199{
200 struct snd_info_entry *entry;
201
202 if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc", substream->proc_root)) != NULL) {
203 entry->c.text.read = snd_pcm_lib_preallocate_proc_read;
204 entry->c.text.write = snd_pcm_lib_preallocate_proc_write;
205 entry->mode |= S_IWUSR;
206 entry->private_data = substream;
207 if (snd_info_register(entry) < 0) {
208 snd_info_free_entry(entry);
209 entry = NULL;
210 }
211 }
212 substream->proc_prealloc_entry = entry;
213 if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc_max", substream->proc_root)) != NULL) {
214 entry->c.text.read = snd_pcm_lib_preallocate_max_proc_read;
215 entry->private_data = substream;
216 if (snd_info_register(entry) < 0) {
217 snd_info_free_entry(entry);
218 entry = NULL;
219 }
220 }
221 substream->proc_prealloc_max_entry = entry;
222}
223
224#else /* !CONFIG_SND_VERBOSE_PROCFS */
225#define preallocate_info_init(s)
226#endif /* CONFIG_SND_VERBOSE_PROCFS */
227
228/*
229 * pre-allocate the buffer and create a proc file for the substream
230 */
231static int snd_pcm_lib_preallocate_pages1(struct snd_pcm_substream *substream,
232 size_t size, size_t max)
233{
234
235 if (size > 0 && preallocate_dma && substream->number < maximum_substreams)
236 preallocate_pcm_pages(substream, size);
237
238 if (substream->dma_buffer.bytes > 0)
239 substream->buffer_bytes_max = substream->dma_buffer.bytes;
240 substream->dma_max = max;
241 preallocate_info_init(substream);
242 return 0;
243}
244
245
246/**
247 * snd_pcm_lib_preallocate_pages - pre-allocation for the given DMA type
248 * @substream: the pcm substream instance
249 * @type: DMA type (SNDRV_DMA_TYPE_*)
250 * @data: DMA type dependent data
251 * @size: the requested pre-allocation size in bytes
252 * @max: the max. allowed pre-allocation size
253 *
254 * Do pre-allocation for the given DMA buffer type.
255 *
256 * Return: Zero if successful, or a negative error code on failure.
257 */
258int snd_pcm_lib_preallocate_pages(struct snd_pcm_substream *substream,
259 int type, struct device *data,
260 size_t size, size_t max)
261{
262 substream->dma_buffer.dev.type = type;
263 substream->dma_buffer.dev.dev = data;
264 return snd_pcm_lib_preallocate_pages1(substream, size, max);
265}
266
267EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages);
268
269/**
270 * snd_pcm_lib_preallocate_pages_for_all - pre-allocation for continuous memory type (all substreams)
271 * @pcm: the pcm instance
272 * @type: DMA type (SNDRV_DMA_TYPE_*)
273 * @data: DMA type dependent data
274 * @size: the requested pre-allocation size in bytes
275 * @max: the max. allowed pre-allocation size
276 *
277 * Do pre-allocation to all substreams of the given pcm for the
278 * specified DMA type.
279 *
280 * Return: Zero if successful, or a negative error code on failure.
281 */
282int snd_pcm_lib_preallocate_pages_for_all(struct snd_pcm *pcm,
283 int type, void *data,
284 size_t size, size_t max)
285{
286 struct snd_pcm_substream *substream;
287 int stream, err;
288
289 for (stream = 0; stream < 2; stream++)
290 for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
291 if ((err = snd_pcm_lib_preallocate_pages(substream, type, data, size, max)) < 0)
292 return err;
293 return 0;
294}
295
296EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages_for_all);
297
298#ifdef CONFIG_SND_DMA_SGBUF
299/**
300 * snd_pcm_sgbuf_ops_page - get the page struct at the given offset
301 * @substream: the pcm substream instance
302 * @offset: the buffer offset
303 *
304 * Used as the page callback of PCM ops.
305 *
306 * Return: The page struct at the given buffer offset. %NULL on failure.
307 */
308struct page *snd_pcm_sgbuf_ops_page(struct snd_pcm_substream *substream, unsigned long offset)
309{
310 struct snd_sg_buf *sgbuf = snd_pcm_substream_sgbuf(substream);
311
312 unsigned int idx = offset >> PAGE_SHIFT;
313 if (idx >= (unsigned int)sgbuf->pages)
314 return NULL;
315 return sgbuf->page_table[idx];
316}
317
318EXPORT_SYMBOL(snd_pcm_sgbuf_ops_page);
319#endif /* CONFIG_SND_DMA_SGBUF */
320
321/**
322 * snd_pcm_lib_malloc_pages - allocate the DMA buffer
323 * @substream: the substream to allocate the DMA buffer to
324 * @size: the requested buffer size in bytes
325 *
326 * Allocates the DMA buffer on the BUS type given earlier to
327 * snd_pcm_lib_preallocate_xxx_pages().
328 *
329 * Return: 1 if the buffer is changed, 0 if not changed, or a negative
330 * code on failure.
331 */
332int snd_pcm_lib_malloc_pages(struct snd_pcm_substream *substream, size_t size)
333{
334 struct snd_pcm_runtime *runtime;
335 struct snd_dma_buffer *dmab = NULL;
336
337 if (PCM_RUNTIME_CHECK(substream))
338 return -EINVAL;
339 if (snd_BUG_ON(substream->dma_buffer.dev.type ==
340 SNDRV_DMA_TYPE_UNKNOWN))
341 return -EINVAL;
342 runtime = substream->runtime;
343
344 if (runtime->dma_buffer_p) {
345 /* perphaps, we might free the large DMA memory region
346 to save some space here, but the actual solution
347 costs us less time */
348 if (runtime->dma_buffer_p->bytes >= size) {
349 runtime->dma_bytes = size;
350 return 0; /* ok, do not change */
351 }
352 snd_pcm_lib_free_pages(substream);
353 }
354 if (substream->dma_buffer.area != NULL &&
355 substream->dma_buffer.bytes >= size) {
356 dmab = &substream->dma_buffer; /* use the pre-allocated buffer */
357 } else {
358 dmab = kzalloc(sizeof(*dmab), GFP_KERNEL);
359 if (! dmab)
360 return -ENOMEM;
361 dmab->dev = substream->dma_buffer.dev;
362 if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
363 substream->dma_buffer.dev.dev,
364 size, dmab) < 0) {
365 kfree(dmab);
366 return -ENOMEM;
367 }
368 }
369 snd_pcm_set_runtime_buffer(substream, dmab);
370 runtime->dma_bytes = size;
371 return 1; /* area was changed */
372}
373
374EXPORT_SYMBOL(snd_pcm_lib_malloc_pages);
375
376/**
377 * snd_pcm_lib_free_pages - release the allocated DMA buffer.
378 * @substream: the substream to release the DMA buffer
379 *
380 * Releases the DMA buffer allocated via snd_pcm_lib_malloc_pages().
381 *
382 * Return: Zero if successful, or a negative error code on failure.
383 */
384int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream)
385{
386 struct snd_pcm_runtime *runtime;
387
388 if (PCM_RUNTIME_CHECK(substream))
389 return -EINVAL;
390 runtime = substream->runtime;
391 if (runtime->dma_area == NULL)
392 return 0;
393 if (runtime->dma_buffer_p != &substream->dma_buffer) {
394 /* it's a newly allocated buffer. release it now. */
395 snd_dma_free_pages(runtime->dma_buffer_p);
396 kfree(runtime->dma_buffer_p);
397 }
398 snd_pcm_set_runtime_buffer(substream, NULL);
399 return 0;
400}
401
402EXPORT_SYMBOL(snd_pcm_lib_free_pages);
403
404int _snd_pcm_lib_alloc_vmalloc_buffer(struct snd_pcm_substream *substream,
405 size_t size, gfp_t gfp_flags)
406{
407 struct snd_pcm_runtime *runtime;
408
409 if (PCM_RUNTIME_CHECK(substream))
410 return -EINVAL;
411 runtime = substream->runtime;
412 if (runtime->dma_area) {
413 if (runtime->dma_bytes >= size)
414 return 0; /* already large enough */
415 vfree(runtime->dma_area);
416 }
417 runtime->dma_area = __vmalloc(size, gfp_flags, PAGE_KERNEL);
418 if (!runtime->dma_area)
419 return -ENOMEM;
420 runtime->dma_bytes = size;
421 return 1;
422}
423EXPORT_SYMBOL(_snd_pcm_lib_alloc_vmalloc_buffer);
424
425/**
426 * snd_pcm_lib_free_vmalloc_buffer - free vmalloc buffer
427 * @substream: the substream with a buffer allocated by
428 * snd_pcm_lib_alloc_vmalloc_buffer()
429 *
430 * Return: Zero if successful, or a negative error code on failure.
431 */
432int snd_pcm_lib_free_vmalloc_buffer(struct snd_pcm_substream *substream)
433{
434 struct snd_pcm_runtime *runtime;
435
436 if (PCM_RUNTIME_CHECK(substream))
437 return -EINVAL;
438 runtime = substream->runtime;
439 vfree(runtime->dma_area);
440 runtime->dma_area = NULL;
441 return 0;
442}
443EXPORT_SYMBOL(snd_pcm_lib_free_vmalloc_buffer);
444
445/**
446 * snd_pcm_lib_get_vmalloc_page - map vmalloc buffer offset to page struct
447 * @substream: the substream with a buffer allocated by
448 * snd_pcm_lib_alloc_vmalloc_buffer()
449 * @offset: offset in the buffer
450 *
451 * This function is to be used as the page callback in the PCM ops.
452 *
453 * Return: The page struct, or %NULL on failure.
454 */
455struct page *snd_pcm_lib_get_vmalloc_page(struct snd_pcm_substream *substream,
456 unsigned long offset)
457{
458 return vmalloc_to_page(substream->runtime->dma_area + offset);
459}
460EXPORT_SYMBOL(snd_pcm_lib_get_vmalloc_page);