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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 : : int err;
55 : :
56 : : /* already reserved? */
57 [ # # ]: 0 : if (snd_dma_get_reserved_buf(dmab, substream->dma_buf_id) > 0) {
58 [ # # ]: 0 : if (dmab->bytes >= size)
59 : : return 0; /* yes */
60 : : /* no, free the reserved block */
61 : 0 : snd_dma_free_pages(dmab);
62 : 0 : dmab->bytes = 0;
63 : : }
64 : :
65 : : do {
66 [ # # ]: 0 : if ((err = snd_dma_alloc_pages(dmab->dev.type, dmab->dev.dev,
67 : : size, dmab)) < 0) {
68 [ # # ]: 0 : if (err != -ENOMEM)
69 : : return err; /* fatal error */
70 : : } else
71 : : return 0;
72 : 0 : size >>= 1;
73 [ # # ]: 0 : } while (size >= snd_minimum_buffer);
74 : 0 : dmab->bytes = 0; /* tell error */
75 : 0 : return 0;
76 : : }
77 : :
78 : : /*
79 : : * release the preallocated buffer if not yet done.
80 : : */
81 : 0 : static void snd_pcm_lib_preallocate_dma_free(struct snd_pcm_substream *substream)
82 : : {
83 [ # # ]: 0 : if (substream->dma_buffer.area == NULL)
84 : 0 : return;
85 [ # # ]: 0 : if (substream->dma_buf_id)
86 : 0 : snd_dma_reserve_buf(&substream->dma_buffer, substream->dma_buf_id);
87 : : else
88 : 0 : snd_dma_free_pages(&substream->dma_buffer);
89 : 0 : substream->dma_buffer.area = NULL;
90 : : }
91 : :
92 : : /**
93 : : * snd_pcm_lib_preallocate_free - release the preallocated buffer of the specified substream.
94 : : * @substream: the pcm substream instance
95 : : *
96 : : * Releases the pre-allocated buffer of the given substream.
97 : : *
98 : : * Return: Zero if successful, or a negative error code on failure.
99 : : */
100 : 0 : int snd_pcm_lib_preallocate_free(struct snd_pcm_substream *substream)
101 : : {
102 : 0 : snd_pcm_lib_preallocate_dma_free(substream);
103 : : #ifdef CONFIG_SND_VERBOSE_PROCFS
104 : 0 : snd_info_free_entry(substream->proc_prealloc_max_entry);
105 : 0 : substream->proc_prealloc_max_entry = NULL;
106 : 0 : snd_info_free_entry(substream->proc_prealloc_entry);
107 : 0 : substream->proc_prealloc_entry = NULL;
108 : : #endif
109 : 0 : return 0;
110 : : }
111 : :
112 : : /**
113 : : * snd_pcm_lib_preallocate_free_for_all - release all pre-allocated buffers on the pcm
114 : : * @pcm: the pcm instance
115 : : *
116 : : * Releases all the pre-allocated buffers on the given pcm.
117 : : *
118 : : * Return: Zero if successful, or a negative error code on failure.
119 : : */
120 : 0 : int snd_pcm_lib_preallocate_free_for_all(struct snd_pcm *pcm)
121 : : {
122 : : struct snd_pcm_substream *substream;
123 : : int stream;
124 : :
125 [ # # ]: 0 : for (stream = 0; stream < 2; stream++)
126 [ # # ]: 0 : for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
127 : 0 : snd_pcm_lib_preallocate_free(substream);
128 : 0 : return 0;
129 : : }
130 : :
131 : : EXPORT_SYMBOL(snd_pcm_lib_preallocate_free_for_all);
132 : :
133 : : #ifdef CONFIG_SND_VERBOSE_PROCFS
134 : : /*
135 : : * read callback for prealloc proc file
136 : : *
137 : : * prints the current allocated size in kB.
138 : : */
139 : 0 : static void snd_pcm_lib_preallocate_proc_read(struct snd_info_entry *entry,
140 : : struct snd_info_buffer *buffer)
141 : : {
142 : 2 : struct snd_pcm_substream *substream = entry->private_data;
143 : 2 : snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_buffer.bytes / 1024);
144 : 2 : }
145 : :
146 : : /*
147 : : * read callback for prealloc_max proc file
148 : : *
149 : : * prints the maximum allowed size in kB.
150 : : */
151 : 0 : static void snd_pcm_lib_preallocate_max_proc_read(struct snd_info_entry *entry,
152 : : struct snd_info_buffer *buffer)
153 : : {
154 : 2 : struct snd_pcm_substream *substream = entry->private_data;
155 : 2 : snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_max / 1024);
156 : 2 : }
157 : :
158 : : /*
159 : : * write callback for prealloc proc file
160 : : *
161 : : * accepts the preallocation size in kB.
162 : : */
163 : 0 : static void snd_pcm_lib_preallocate_proc_write(struct snd_info_entry *entry,
164 : : struct snd_info_buffer *buffer)
165 : : {
166 : 0 : struct snd_pcm_substream *substream = entry->private_data;
167 : : char line[64], str[64];
168 : : size_t size;
169 : : struct snd_dma_buffer new_dmab;
170 : :
171 [ # # ]: 0 : if (substream->runtime) {
172 : 0 : buffer->error = -EBUSY;
173 : 0 : return;
174 : : }
175 [ # # ]: 0 : if (!snd_info_get_line(buffer, line, sizeof(line))) {
176 : 0 : snd_info_get_str(str, line, sizeof(str));
177 : 0 : size = simple_strtoul(str, NULL, 10) * 1024;
178 [ # # ][ # # ]: 0 : if ((size != 0 && size < 8192) || size > substream->dma_max) {
179 : 0 : buffer->error = -EINVAL;
180 : 0 : return;
181 : : }
182 [ # # ]: 0 : if (substream->dma_buffer.bytes == size)
183 : : return;
184 : 0 : memset(&new_dmab, 0, sizeof(new_dmab));
185 : 0 : new_dmab.dev = substream->dma_buffer.dev;
186 [ # # ]: 0 : if (size > 0) {
187 [ # # ]: 0 : if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
188 : : substream->dma_buffer.dev.dev,
189 : : size, &new_dmab) < 0) {
190 : 0 : buffer->error = -ENOMEM;
191 : 0 : return;
192 : : }
193 : 0 : substream->buffer_bytes_max = size;
194 : : } else {
195 : 0 : substream->buffer_bytes_max = UINT_MAX;
196 : : }
197 [ # # ]: 0 : if (substream->dma_buffer.area)
198 : 0 : snd_dma_free_pages(&substream->dma_buffer);
199 : 0 : substream->dma_buffer = new_dmab;
200 : : } else {
201 : 0 : buffer->error = -EINVAL;
202 : : }
203 : : }
204 : :
205 : : static inline void preallocate_info_init(struct snd_pcm_substream *substream)
206 : : {
207 : : struct snd_info_entry *entry;
208 : :
209 [ # # ]: 0 : if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc", substream->proc_root)) != NULL) {
210 : 0 : entry->c.text.read = snd_pcm_lib_preallocate_proc_read;
211 : 0 : entry->c.text.write = snd_pcm_lib_preallocate_proc_write;
212 : 0 : entry->mode |= S_IWUSR;
213 : 0 : entry->private_data = substream;
214 [ # # ]: 0 : if (snd_info_register(entry) < 0) {
215 : 0 : snd_info_free_entry(entry);
216 : : entry = NULL;
217 : : }
218 : : }
219 : 0 : substream->proc_prealloc_entry = entry;
220 [ # # ]: 0 : if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc_max", substream->proc_root)) != NULL) {
221 : 0 : entry->c.text.read = snd_pcm_lib_preallocate_max_proc_read;
222 : 0 : entry->private_data = substream;
223 [ # # ]: 0 : if (snd_info_register(entry) < 0) {
224 : 0 : snd_info_free_entry(entry);
225 : : entry = NULL;
226 : : }
227 : : }
228 : 0 : substream->proc_prealloc_max_entry = entry;
229 : : }
230 : :
231 : : #else /* !CONFIG_SND_VERBOSE_PROCFS */
232 : : #define preallocate_info_init(s)
233 : : #endif /* CONFIG_SND_VERBOSE_PROCFS */
234 : :
235 : : /*
236 : : * pre-allocate the buffer and create a proc file for the substream
237 : : */
238 : 0 : static int snd_pcm_lib_preallocate_pages1(struct snd_pcm_substream *substream,
239 : : size_t size, size_t max)
240 : : {
241 : :
242 [ # # ][ # # ]: 0 : if (size > 0 && preallocate_dma && substream->number < maximum_substreams)
[ # # ]
243 : 0 : preallocate_pcm_pages(substream, size);
244 : :
245 [ # # ]: 0 : if (substream->dma_buffer.bytes > 0)
246 : 0 : substream->buffer_bytes_max = substream->dma_buffer.bytes;
247 : 0 : substream->dma_max = max;
248 : : preallocate_info_init(substream);
249 : 0 : return 0;
250 : : }
251 : :
252 : :
253 : : /**
254 : : * snd_pcm_lib_preallocate_pages - pre-allocation for the given DMA type
255 : : * @substream: the pcm substream instance
256 : : * @type: DMA type (SNDRV_DMA_TYPE_*)
257 : : * @data: DMA type dependent data
258 : : * @size: the requested pre-allocation size in bytes
259 : : * @max: the max. allowed pre-allocation size
260 : : *
261 : : * Do pre-allocation for the given DMA buffer type.
262 : : *
263 : : * When substream->dma_buf_id is set, the function tries to look for
264 : : * the reserved buffer, and the buffer is not freed but reserved at
265 : : * destruction time. The dma_buf_id must be unique for all systems
266 : : * (in the same DMA buffer type) e.g. using snd_dma_pci_buf_id().
267 : : *
268 : : * Return: Zero if successful, or a negative error code on failure.
269 : : */
270 : 0 : int snd_pcm_lib_preallocate_pages(struct snd_pcm_substream *substream,
271 : : int type, struct device *data,
272 : : size_t size, size_t max)
273 : : {
274 : 0 : substream->dma_buffer.dev.type = type;
275 : 0 : substream->dma_buffer.dev.dev = data;
276 : 0 : return snd_pcm_lib_preallocate_pages1(substream, size, max);
277 : : }
278 : :
279 : : EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages);
280 : :
281 : : /**
282 : : * snd_pcm_lib_preallocate_pages_for_all - pre-allocation for continuous memory type (all substreams)
283 : : * @pcm: the pcm instance
284 : : * @type: DMA type (SNDRV_DMA_TYPE_*)
285 : : * @data: DMA type dependent data
286 : : * @size: the requested pre-allocation size in bytes
287 : : * @max: the max. allowed pre-allocation size
288 : : *
289 : : * Do pre-allocation to all substreams of the given pcm for the
290 : : * specified DMA type.
291 : : *
292 : : * Return: Zero if successful, or a negative error code on failure.
293 : : */
294 : 0 : int snd_pcm_lib_preallocate_pages_for_all(struct snd_pcm *pcm,
295 : : int type, void *data,
296 : : size_t size, size_t max)
297 : : {
298 : : struct snd_pcm_substream *substream;
299 : : int stream, err;
300 : :
301 [ # # ]: 0 : for (stream = 0; stream < 2; stream++)
302 [ # # ]: 0 : for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
303 [ # # ]: 0 : if ((err = snd_pcm_lib_preallocate_pages(substream, type, data, size, max)) < 0)
304 : : return err;
305 : : return 0;
306 : : }
307 : :
308 : : EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages_for_all);
309 : :
310 : : #ifdef CONFIG_SND_DMA_SGBUF
311 : : /**
312 : : * snd_pcm_sgbuf_ops_page - get the page struct at the given offset
313 : : * @substream: the pcm substream instance
314 : : * @offset: the buffer offset
315 : : *
316 : : * Used as the page callback of PCM ops.
317 : : *
318 : : * Return: The page struct at the given buffer offset. %NULL on failure.
319 : : */
320 : : struct page *snd_pcm_sgbuf_ops_page(struct snd_pcm_substream *substream, unsigned long offset)
321 : : {
322 : : struct snd_sg_buf *sgbuf = snd_pcm_substream_sgbuf(substream);
323 : :
324 : : unsigned int idx = offset >> PAGE_SHIFT;
325 : : if (idx >= (unsigned int)sgbuf->pages)
326 : : return NULL;
327 : : return sgbuf->page_table[idx];
328 : : }
329 : :
330 : : EXPORT_SYMBOL(snd_pcm_sgbuf_ops_page);
331 : : #endif /* CONFIG_SND_DMA_SGBUF */
332 : :
333 : : /**
334 : : * snd_pcm_lib_malloc_pages - allocate the DMA buffer
335 : : * @substream: the substream to allocate the DMA buffer to
336 : : * @size: the requested buffer size in bytes
337 : : *
338 : : * Allocates the DMA buffer on the BUS type given earlier to
339 : : * snd_pcm_lib_preallocate_xxx_pages().
340 : : *
341 : : * Return: 1 if the buffer is changed, 0 if not changed, or a negative
342 : : * code on failure.
343 : : */
344 : 0 : int snd_pcm_lib_malloc_pages(struct snd_pcm_substream *substream, size_t size)
345 : : {
346 : : struct snd_pcm_runtime *runtime;
347 : : struct snd_dma_buffer *dmab = NULL;
348 : :
349 [ # # ][ # # ]: 0 : if (PCM_RUNTIME_CHECK(substream))
[ # # ]
350 : : return -EINVAL;
351 [ # # ]: 0 : if (snd_BUG_ON(substream->dma_buffer.dev.type ==
352 : : SNDRV_DMA_TYPE_UNKNOWN))
353 : : return -EINVAL;
354 : 0 : runtime = substream->runtime;
355 : :
356 [ # # ]: 0 : if (runtime->dma_buffer_p) {
357 : : /* perphaps, we might free the large DMA memory region
358 : : to save some space here, but the actual solution
359 : : costs us less time */
360 [ # # ]: 0 : if (runtime->dma_buffer_p->bytes >= size) {
361 : 0 : runtime->dma_bytes = size;
362 : 0 : return 0; /* ok, do not change */
363 : : }
364 : 0 : snd_pcm_lib_free_pages(substream);
365 : : }
366 [ # # ][ # # ]: 0 : if (substream->dma_buffer.area != NULL &&
367 : 0 : substream->dma_buffer.bytes >= size) {
368 : 0 : dmab = &substream->dma_buffer; /* use the pre-allocated buffer */
369 : : } else {
370 : : dmab = kzalloc(sizeof(*dmab), GFP_KERNEL);
371 [ # # ]: 0 : if (! dmab)
372 : : return -ENOMEM;
373 : 0 : dmab->dev = substream->dma_buffer.dev;
374 [ # # ]: 0 : if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
375 : : substream->dma_buffer.dev.dev,
376 : : size, dmab) < 0) {
377 : 0 : kfree(dmab);
378 : 0 : return -ENOMEM;
379 : : }
380 : : }
381 : : snd_pcm_set_runtime_buffer(substream, dmab);
382 : 0 : runtime->dma_bytes = size;
383 : 0 : return 1; /* area was changed */
384 : : }
385 : :
386 : : EXPORT_SYMBOL(snd_pcm_lib_malloc_pages);
387 : :
388 : : /**
389 : : * snd_pcm_lib_free_pages - release the allocated DMA buffer.
390 : : * @substream: the substream to release the DMA buffer
391 : : *
392 : : * Releases the DMA buffer allocated via snd_pcm_lib_malloc_pages().
393 : : *
394 : : * Return: Zero if successful, or a negative error code on failure.
395 : : */
396 : 0 : int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream)
397 : : {
398 : : struct snd_pcm_runtime *runtime;
399 : :
400 [ # # ][ # # ]: 0 : if (PCM_RUNTIME_CHECK(substream))
[ # # ]
401 : : return -EINVAL;
402 : 0 : runtime = substream->runtime;
403 [ # # ]: 0 : if (runtime->dma_area == NULL)
404 : : return 0;
405 [ # # ]: 0 : if (runtime->dma_buffer_p != &substream->dma_buffer) {
406 : : /* it's a newly allocated buffer. release it now. */
407 : 0 : snd_dma_free_pages(runtime->dma_buffer_p);
408 : 0 : kfree(runtime->dma_buffer_p);
409 : : }
410 : : snd_pcm_set_runtime_buffer(substream, NULL);
411 : 0 : return 0;
412 : : }
413 : :
414 : : EXPORT_SYMBOL(snd_pcm_lib_free_pages);
415 : :
416 : 0 : int _snd_pcm_lib_alloc_vmalloc_buffer(struct snd_pcm_substream *substream,
417 : : size_t size, gfp_t gfp_flags)
418 : : {
419 : : struct snd_pcm_runtime *runtime;
420 : :
421 [ # # ][ # # ]: 0 : if (PCM_RUNTIME_CHECK(substream))
[ # # ]
422 : : return -EINVAL;
423 : 0 : runtime = substream->runtime;
424 [ # # ]: 0 : if (runtime->dma_area) {
425 [ # # ]: 0 : if (runtime->dma_bytes >= size)
426 : : return 0; /* already large enough */
427 : 0 : vfree(runtime->dma_area);
428 : : }
429 : 0 : runtime->dma_area = __vmalloc(size, gfp_flags, PAGE_KERNEL);
430 [ # # ]: 0 : if (!runtime->dma_area)
431 : : return -ENOMEM;
432 : 0 : runtime->dma_bytes = size;
433 : 0 : return 1;
434 : : }
435 : : EXPORT_SYMBOL(_snd_pcm_lib_alloc_vmalloc_buffer);
436 : :
437 : : /**
438 : : * snd_pcm_lib_free_vmalloc_buffer - free vmalloc buffer
439 : : * @substream: the substream with a buffer allocated by
440 : : * snd_pcm_lib_alloc_vmalloc_buffer()
441 : : *
442 : : * Return: Zero if successful, or a negative error code on failure.
443 : : */
444 : 0 : int snd_pcm_lib_free_vmalloc_buffer(struct snd_pcm_substream *substream)
445 : : {
446 : : struct snd_pcm_runtime *runtime;
447 : :
448 [ # # ][ # # ]: 0 : if (PCM_RUNTIME_CHECK(substream))
[ # # ]
449 : : return -EINVAL;
450 : 0 : runtime = substream->runtime;
451 : 0 : vfree(runtime->dma_area);
452 : 0 : runtime->dma_area = NULL;
453 : 0 : return 0;
454 : : }
455 : : EXPORT_SYMBOL(snd_pcm_lib_free_vmalloc_buffer);
456 : :
457 : : /**
458 : : * snd_pcm_lib_get_vmalloc_page - map vmalloc buffer offset to page struct
459 : : * @substream: the substream with a buffer allocated by
460 : : * snd_pcm_lib_alloc_vmalloc_buffer()
461 : : * @offset: offset in the buffer
462 : : *
463 : : * This function is to be used as the page callback in the PCM ops.
464 : : *
465 : : * Return: The page struct, or %NULL on failure.
466 : : */
467 : 0 : struct page *snd_pcm_lib_get_vmalloc_page(struct snd_pcm_substream *substream,
468 : : unsigned long offset)
469 : : {
470 : 0 : return vmalloc_to_page(substream->runtime->dma_area + offset);
471 : : }
472 : : EXPORT_SYMBOL(snd_pcm_lib_get_vmalloc_page);
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