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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 <linux/export.h>
29 : : #include <sound/core.h>
30 : : #include <sound/pcm.h>
31 : : #include <sound/info.h>
32 : : #include <sound/initval.h>
33 : :
34 : : static int preallocate_dma = 1;
35 : : module_param(preallocate_dma, int, 0444);
36 : : MODULE_PARM_DESC(preallocate_dma, "Preallocate DMA memory when the PCM devices are initialized.");
37 : :
38 : : static int maximum_substreams = 4;
39 : : module_param(maximum_substreams, int, 0444);
40 : : MODULE_PARM_DESC(maximum_substreams, "Maximum substreams with preallocated DMA memory.");
41 : :
42 : : static 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 : : */
51 : 0 : static int preallocate_pcm_pages(struct snd_pcm_substream *substream, size_t size)
52 : : {
53 : 0 : struct snd_dma_buffer *dmab = &substream->dma_buffer;
54 : : size_t orig_size = size;
55 : : int err;
56 : :
57 : : do {
58 [ # # ]: 0 : if ((err = snd_dma_alloc_pages(dmab->dev.type, dmab->dev.dev,
59 : : size, dmab)) < 0) {
60 [ # # ]: 0 : if (err != -ENOMEM)
61 : : return err; /* fatal error */
62 : : } else
63 : : return 0;
64 : 0 : size >>= 1;
65 [ # # ]: 0 : } while (size >= snd_minimum_buffer);
66 : 0 : dmab->bytes = 0; /* tell error */
67 [ # # ]: 0 : 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 : 0 : return 0;
72 : : }
73 : :
74 : : /*
75 : : * release the preallocated buffer if not yet done.
76 : : */
77 : : static void snd_pcm_lib_preallocate_dma_free(struct snd_pcm_substream *substream)
78 : : {
79 [ # # ]: 0 : if (substream->dma_buffer.area == NULL)
80 : : return;
81 : 0 : snd_dma_free_pages(&substream->dma_buffer);
82 : 0 : 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 : : */
93 : 0 : int 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 : 0 : snd_info_free_entry(substream->proc_prealloc_max_entry);
98 : 0 : substream->proc_prealloc_max_entry = NULL;
99 : 0 : snd_info_free_entry(substream->proc_prealloc_entry);
100 : 0 : substream->proc_prealloc_entry = NULL;
101 : : #endif
102 : 0 : 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 : : */
113 : 0 : int snd_pcm_lib_preallocate_free_for_all(struct snd_pcm *pcm)
114 : : {
115 : : struct snd_pcm_substream *substream;
116 : : int stream;
117 : :
118 [ # # ]: 0 : for (stream = 0; stream < 2; stream++)
119 [ # # ]: 0 : for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
120 : 0 : snd_pcm_lib_preallocate_free(substream);
121 : 0 : return 0;
122 : : }
123 : :
124 : : EXPORT_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 : : */
132 : 0 : static void snd_pcm_lib_preallocate_proc_read(struct snd_info_entry *entry,
133 : : struct snd_info_buffer *buffer)
134 : : {
135 : 2 : struct snd_pcm_substream *substream = entry->private_data;
136 : 2 : snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_buffer.bytes / 1024);
137 : 2 : }
138 : :
139 : : /*
140 : : * read callback for prealloc_max proc file
141 : : *
142 : : * prints the maximum allowed size in kB.
143 : : */
144 : 0 : static void snd_pcm_lib_preallocate_max_proc_read(struct snd_info_entry *entry,
145 : : struct snd_info_buffer *buffer)
146 : : {
147 : 2 : struct snd_pcm_substream *substream = entry->private_data;
148 : 2 : snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_max / 1024);
149 : 2 : }
150 : :
151 : : /*
152 : : * write callback for prealloc proc file
153 : : *
154 : : * accepts the preallocation size in kB.
155 : : */
156 : 0 : static void snd_pcm_lib_preallocate_proc_write(struct snd_info_entry *entry,
157 : : struct snd_info_buffer *buffer)
158 : : {
159 : 0 : 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 [ # # ]: 0 : if (substream->runtime) {
165 : 0 : buffer->error = -EBUSY;
166 : 0 : return;
167 : : }
168 [ # # ]: 0 : if (!snd_info_get_line(buffer, line, sizeof(line))) {
169 : 0 : snd_info_get_str(str, line, sizeof(str));
170 : 0 : size = simple_strtoul(str, NULL, 10) * 1024;
171 [ # # ][ # # ]: 0 : if ((size != 0 && size < 8192) || size > substream->dma_max) {
172 : 0 : buffer->error = -EINVAL;
173 : 0 : return;
174 : : }
175 [ # # ]: 0 : if (substream->dma_buffer.bytes == size)
176 : : return;
177 : 0 : memset(&new_dmab, 0, sizeof(new_dmab));
178 : 0 : new_dmab.dev = substream->dma_buffer.dev;
179 [ # # ]: 0 : if (size > 0) {
180 [ # # ]: 0 : if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
181 : : substream->dma_buffer.dev.dev,
182 : : size, &new_dmab) < 0) {
183 : 0 : buffer->error = -ENOMEM;
184 : 0 : return;
185 : : }
186 : 0 : substream->buffer_bytes_max = size;
187 : : } else {
188 : 0 : substream->buffer_bytes_max = UINT_MAX;
189 : : }
190 [ # # ]: 0 : if (substream->dma_buffer.area)
191 : 0 : snd_dma_free_pages(&substream->dma_buffer);
192 : 0 : substream->dma_buffer = new_dmab;
193 : : } else {
194 : 0 : buffer->error = -EINVAL;
195 : : }
196 : : }
197 : :
198 : : static inline void preallocate_info_init(struct snd_pcm_substream *substream)
199 : : {
200 : : struct snd_info_entry *entry;
201 : :
202 [ # # ]: 0 : if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc", substream->proc_root)) != NULL) {
203 : 0 : entry->c.text.read = snd_pcm_lib_preallocate_proc_read;
204 : 0 : entry->c.text.write = snd_pcm_lib_preallocate_proc_write;
205 : 0 : entry->mode |= S_IWUSR;
206 : 0 : entry->private_data = substream;
207 [ # # ]: 0 : if (snd_info_register(entry) < 0) {
208 : 0 : snd_info_free_entry(entry);
209 : : entry = NULL;
210 : : }
211 : : }
212 : 0 : substream->proc_prealloc_entry = entry;
213 [ # # ]: 0 : if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc_max", substream->proc_root)) != NULL) {
214 : 0 : entry->c.text.read = snd_pcm_lib_preallocate_max_proc_read;
215 : 0 : entry->private_data = substream;
216 [ # # ]: 0 : if (snd_info_register(entry) < 0) {
217 : 0 : snd_info_free_entry(entry);
218 : : entry = NULL;
219 : : }
220 : : }
221 : 0 : 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 : : */
231 : 0 : static int snd_pcm_lib_preallocate_pages1(struct snd_pcm_substream *substream,
232 : : size_t size, size_t max)
233 : : {
234 : :
235 [ # # ][ # # ]: 0 : if (size > 0 && preallocate_dma && substream->number < maximum_substreams)
[ # # ]
236 : 0 : preallocate_pcm_pages(substream, size);
237 : :
238 [ # # ]: 0 : if (substream->dma_buffer.bytes > 0)
239 : 0 : substream->buffer_bytes_max = substream->dma_buffer.bytes;
240 : 0 : substream->dma_max = max;
241 : : preallocate_info_init(substream);
242 : 0 : 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 : : */
258 : 0 : int 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 : 0 : substream->dma_buffer.dev.type = type;
263 : 0 : substream->dma_buffer.dev.dev = data;
264 : 0 : return snd_pcm_lib_preallocate_pages1(substream, size, max);
265 : : }
266 : :
267 : : EXPORT_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 : : */
282 : 0 : int 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 [ # # ]: 0 : for (stream = 0; stream < 2; stream++)
290 [ # # ]: 0 : for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
291 [ # # ]: 0 : if ((err = snd_pcm_lib_preallocate_pages(substream, type, data, size, max)) < 0)
292 : : return err;
293 : : return 0;
294 : : }
295 : :
296 : : EXPORT_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 : : */
308 : : struct 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 : :
318 : : EXPORT_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 : : */
332 : 0 : int 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 [ # # ][ # # ]: 0 : if (PCM_RUNTIME_CHECK(substream))
[ # # ]
338 : : return -EINVAL;
339 [ # # ]: 0 : if (snd_BUG_ON(substream->dma_buffer.dev.type ==
340 : : SNDRV_DMA_TYPE_UNKNOWN))
341 : : return -EINVAL;
342 : 0 : runtime = substream->runtime;
343 : :
344 [ # # ]: 0 : 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 [ # # ]: 0 : if (runtime->dma_buffer_p->bytes >= size) {
349 : 0 : runtime->dma_bytes = size;
350 : 0 : return 0; /* ok, do not change */
351 : : }
352 : 0 : snd_pcm_lib_free_pages(substream);
353 : : }
354 [ # # ][ # # ]: 0 : if (substream->dma_buffer.area != NULL &&
355 : 0 : substream->dma_buffer.bytes >= size) {
356 : 0 : dmab = &substream->dma_buffer; /* use the pre-allocated buffer */
357 : : } else {
358 : : dmab = kzalloc(sizeof(*dmab), GFP_KERNEL);
359 [ # # ]: 0 : if (! dmab)
360 : : return -ENOMEM;
361 : 0 : dmab->dev = substream->dma_buffer.dev;
362 [ # # ]: 0 : if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
363 : : substream->dma_buffer.dev.dev,
364 : : size, dmab) < 0) {
365 : 0 : kfree(dmab);
366 : 0 : return -ENOMEM;
367 : : }
368 : : }
369 : : snd_pcm_set_runtime_buffer(substream, dmab);
370 : 0 : runtime->dma_bytes = size;
371 : 0 : return 1; /* area was changed */
372 : : }
373 : :
374 : : EXPORT_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 : : */
384 : 0 : int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream)
385 : : {
386 : : struct snd_pcm_runtime *runtime;
387 : :
388 [ # # ][ # # ]: 0 : if (PCM_RUNTIME_CHECK(substream))
[ # # ]
389 : : return -EINVAL;
390 : 0 : runtime = substream->runtime;
391 [ # # ]: 0 : if (runtime->dma_area == NULL)
392 : : return 0;
393 [ # # ]: 0 : if (runtime->dma_buffer_p != &substream->dma_buffer) {
394 : : /* it's a newly allocated buffer. release it now. */
395 : 0 : snd_dma_free_pages(runtime->dma_buffer_p);
396 : 0 : kfree(runtime->dma_buffer_p);
397 : : }
398 : : snd_pcm_set_runtime_buffer(substream, NULL);
399 : 0 : return 0;
400 : : }
401 : :
402 : : EXPORT_SYMBOL(snd_pcm_lib_free_pages);
403 : :
404 : 0 : int _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 [ # # ][ # # ]: 0 : if (PCM_RUNTIME_CHECK(substream))
[ # # ]
410 : : return -EINVAL;
411 : 0 : runtime = substream->runtime;
412 [ # # ]: 0 : if (runtime->dma_area) {
413 [ # # ]: 0 : if (runtime->dma_bytes >= size)
414 : : return 0; /* already large enough */
415 : 0 : vfree(runtime->dma_area);
416 : : }
417 : 0 : runtime->dma_area = __vmalloc(size, gfp_flags, PAGE_KERNEL);
418 [ # # ]: 0 : if (!runtime->dma_area)
419 : : return -ENOMEM;
420 : 0 : runtime->dma_bytes = size;
421 : 0 : return 1;
422 : : }
423 : : EXPORT_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 : : */
432 : 0 : int snd_pcm_lib_free_vmalloc_buffer(struct snd_pcm_substream *substream)
433 : : {
434 : : struct snd_pcm_runtime *runtime;
435 : :
436 [ # # ][ # # ]: 0 : if (PCM_RUNTIME_CHECK(substream))
[ # # ]
437 : : return -EINVAL;
438 : 0 : runtime = substream->runtime;
439 : 0 : vfree(runtime->dma_area);
440 : 0 : runtime->dma_area = NULL;
441 : 0 : return 0;
442 : : }
443 : : EXPORT_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 : : */
455 : 0 : struct page *snd_pcm_lib_get_vmalloc_page(struct snd_pcm_substream *substream,
456 : : unsigned long offset)
457 : : {
458 : 0 : return vmalloc_to_page(substream->runtime->dma_area + offset);
459 : : }
460 : : EXPORT_SYMBOL(snd_pcm_lib_get_vmalloc_page);
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