Commit | Line | Data |
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1a59d1b8 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 LT |
2 | /* |
3 | * Digital Audio (PCM) abstract layer | |
c1017a4c | 4 | * Copyright (c) by Jaroslav Kysela <perex@perex.cz> |
1da177e4 LT |
5 | */ |
6 | ||
6cbbfe1c | 7 | #include <linux/io.h> |
1da177e4 LT |
8 | #include <linux/time.h> |
9 | #include <linux/init.h> | |
5a0e3ad6 | 10 | #include <linux/slab.h> |
1da177e4 | 11 | #include <linux/moduleparam.h> |
d81a6d71 | 12 | #include <linux/export.h> |
1da177e4 LT |
13 | #include <sound/core.h> |
14 | #include <sound/pcm.h> | |
15 | #include <sound/info.h> | |
16 | #include <sound/initval.h> | |
0821fd77 | 17 | #include "pcm_local.h" |
1da177e4 LT |
18 | |
19 | static int preallocate_dma = 1; | |
20 | module_param(preallocate_dma, int, 0444); | |
21 | MODULE_PARM_DESC(preallocate_dma, "Preallocate DMA memory when the PCM devices are initialized."); | |
22 | ||
23 | static int maximum_substreams = 4; | |
24 | module_param(maximum_substreams, int, 0444); | |
25 | MODULE_PARM_DESC(maximum_substreams, "Maximum substreams with preallocated DMA memory."); | |
26 | ||
27 | static const size_t snd_minimum_buffer = 16384; | |
28 | ||
d4cfb30f TI |
29 | static unsigned long max_alloc_per_card = 32UL * 1024UL * 1024UL; |
30 | module_param(max_alloc_per_card, ulong, 0644); | |
31 | MODULE_PARM_DESC(max_alloc_per_card, "Max total allocation bytes per card."); | |
32 | ||
bd55842e TI |
33 | static void __update_allocated_size(struct snd_card *card, ssize_t bytes) |
34 | { | |
35 | card->total_pcm_alloc_bytes += bytes; | |
36 | } | |
37 | ||
38 | static void update_allocated_size(struct snd_card *card, ssize_t bytes) | |
39 | { | |
dd0da75b | 40 | guard(mutex)(&card->memory_mutex); |
bd55842e | 41 | __update_allocated_size(card, bytes); |
bd55842e TI |
42 | } |
43 | ||
44 | static void decrease_allocated_size(struct snd_card *card, size_t bytes) | |
45 | { | |
dd0da75b | 46 | guard(mutex)(&card->memory_mutex); |
bd55842e TI |
47 | WARN_ON(card->total_pcm_alloc_bytes < bytes); |
48 | __update_allocated_size(card, -(ssize_t)bytes); | |
bd55842e TI |
49 | } |
50 | ||
d4cfb30f | 51 | static int do_alloc_pages(struct snd_card *card, int type, struct device *dev, |
a25684a9 | 52 | int str, size_t size, struct snd_dma_buffer *dmab) |
d4cfb30f | 53 | { |
a25684a9 | 54 | enum dma_data_direction dir; |
d4cfb30f TI |
55 | int err; |
56 | ||
bd55842e | 57 | /* check and reserve the requested size */ |
dd0da75b TI |
58 | scoped_guard(mutex, &card->memory_mutex) { |
59 | if (max_alloc_per_card && | |
60 | card->total_pcm_alloc_bytes + size > max_alloc_per_card) | |
61 | return -ENOMEM; | |
62 | __update_allocated_size(card, size); | |
bd55842e | 63 | } |
3ad796cb | 64 | |
a25684a9 TI |
65 | if (str == SNDRV_PCM_STREAM_PLAYBACK) |
66 | dir = DMA_TO_DEVICE; | |
67 | else | |
68 | dir = DMA_FROM_DEVICE; | |
69 | err = snd_dma_alloc_dir_pages(type, dev, dir, size, dmab); | |
d4cfb30f | 70 | if (!err) { |
bd55842e TI |
71 | /* the actual allocation size might be bigger than requested, |
72 | * and we need to correct the account | |
73 | */ | |
74 | if (dmab->bytes != size) | |
75 | update_allocated_size(card, dmab->bytes - size); | |
76 | } else { | |
77 | /* take back on allocation failure */ | |
78 | decrease_allocated_size(card, size); | |
d4cfb30f TI |
79 | } |
80 | return err; | |
81 | } | |
82 | ||
83 | static void do_free_pages(struct snd_card *card, struct snd_dma_buffer *dmab) | |
84 | { | |
85 | if (!dmab->area) | |
86 | return; | |
bd55842e | 87 | decrease_allocated_size(card, dmab->bytes); |
d4cfb30f TI |
88 | snd_dma_free_pages(dmab); |
89 | dmab->area = NULL; | |
90 | } | |
1da177e4 LT |
91 | |
92 | /* | |
93 | * try to allocate as the large pages as possible. | |
94 | * stores the resultant memory size in *res_size. | |
95 | * | |
96 | * the minimum size is snd_minimum_buffer. it should be power of 2. | |
97 | */ | |
ac9245a5 TI |
98 | static int preallocate_pcm_pages(struct snd_pcm_substream *substream, |
99 | size_t size, bool no_fallback) | |
1da177e4 LT |
100 | { |
101 | struct snd_dma_buffer *dmab = &substream->dma_buffer; | |
d4cfb30f | 102 | struct snd_card *card = substream->pcm->card; |
6ab08ced | 103 | size_t orig_size = size; |
1da177e4 LT |
104 | int err; |
105 | ||
1da177e4 | 106 | do { |
d4cfb30f | 107 | err = do_alloc_pages(card, dmab->dev.type, dmab->dev.dev, |
a25684a9 | 108 | substream->stream, size, dmab); |
d4cfb30f TI |
109 | if (err != -ENOMEM) |
110 | return err; | |
ac9245a5 TI |
111 | if (no_fallback) |
112 | break; | |
1da177e4 LT |
113 | size >>= 1; |
114 | } while (size >= snd_minimum_buffer); | |
115 | dmab->bytes = 0; /* tell error */ | |
6ab08ced TI |
116 | pr_warn("ALSA pcmC%dD%d%c,%d:%s: cannot preallocate for size %zu\n", |
117 | substream->pcm->card->number, substream->pcm->device, | |
118 | substream->stream ? 'c' : 'p', substream->number, | |
119 | substream->pcm->name, orig_size); | |
ac9245a5 | 120 | return -ENOMEM; |
1da177e4 LT |
121 | } |
122 | ||
1da177e4 LT |
123 | /** |
124 | * snd_pcm_lib_preallocate_free - release the preallocated buffer of the specified substream. | |
125 | * @substream: the pcm substream instance | |
126 | * | |
127 | * Releases the pre-allocated buffer of the given substream. | |
1da177e4 | 128 | */ |
bb580602 | 129 | void snd_pcm_lib_preallocate_free(struct snd_pcm_substream *substream) |
1da177e4 | 130 | { |
f2283366 | 131 | do_free_pages(substream->pcm->card, &substream->dma_buffer); |
1da177e4 LT |
132 | } |
133 | ||
134 | /** | |
135 | * snd_pcm_lib_preallocate_free_for_all - release all pre-allocated buffers on the pcm | |
136 | * @pcm: the pcm instance | |
137 | * | |
138 | * Releases all the pre-allocated buffers on the given pcm. | |
1da177e4 | 139 | */ |
bb580602 | 140 | void snd_pcm_lib_preallocate_free_for_all(struct snd_pcm *pcm) |
1da177e4 | 141 | { |
877211f5 | 142 | struct snd_pcm_substream *substream; |
1da177e4 LT |
143 | int stream; |
144 | ||
8d19b4e0 TI |
145 | for_each_pcm_substream(pcm, stream, substream) |
146 | snd_pcm_lib_preallocate_free(substream); | |
1da177e4 | 147 | } |
e88e8ae6 TI |
148 | EXPORT_SYMBOL(snd_pcm_lib_preallocate_free_for_all); |
149 | ||
b7d90a35 | 150 | #ifdef CONFIG_SND_VERBOSE_PROCFS |
1da177e4 LT |
151 | /* |
152 | * read callback for prealloc proc file | |
153 | * | |
154 | * prints the current allocated size in kB. | |
155 | */ | |
877211f5 TI |
156 | static void snd_pcm_lib_preallocate_proc_read(struct snd_info_entry *entry, |
157 | struct snd_info_buffer *buffer) | |
1da177e4 | 158 | { |
877211f5 | 159 | struct snd_pcm_substream *substream = entry->private_data; |
1da177e4 LT |
160 | snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_buffer.bytes / 1024); |
161 | } | |
162 | ||
c7132aeb JK |
163 | /* |
164 | * read callback for prealloc_max proc file | |
165 | * | |
166 | * prints the maximum allowed size in kB. | |
167 | */ | |
168 | static void snd_pcm_lib_preallocate_max_proc_read(struct snd_info_entry *entry, | |
169 | struct snd_info_buffer *buffer) | |
170 | { | |
171 | struct snd_pcm_substream *substream = entry->private_data; | |
172 | snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_max / 1024); | |
173 | } | |
174 | ||
1da177e4 LT |
175 | /* |
176 | * write callback for prealloc proc file | |
177 | * | |
178 | * accepts the preallocation size in kB. | |
179 | */ | |
877211f5 TI |
180 | static void snd_pcm_lib_preallocate_proc_write(struct snd_info_entry *entry, |
181 | struct snd_info_buffer *buffer) | |
1da177e4 | 182 | { |
877211f5 | 183 | struct snd_pcm_substream *substream = entry->private_data; |
d4cfb30f | 184 | struct snd_card *card = substream->pcm->card; |
1da177e4 | 185 | char line[64], str[64]; |
43b42ed4 | 186 | unsigned long size; |
1da177e4 LT |
187 | struct snd_dma_buffer new_dmab; |
188 | ||
dd0da75b | 189 | guard(mutex)(&substream->pcm->open_mutex); |
1da177e4 LT |
190 | if (substream->runtime) { |
191 | buffer->error = -EBUSY; | |
dd0da75b | 192 | return; |
1da177e4 LT |
193 | } |
194 | if (!snd_info_get_line(buffer, line, sizeof(line))) { | |
195 | snd_info_get_str(str, line, sizeof(str)); | |
61bc4def HL |
196 | buffer->error = kstrtoul(str, 10, &size); |
197 | if (buffer->error != 0) | |
198 | return; | |
199 | size *= 1024; | |
1da177e4 LT |
200 | if ((size != 0 && size < 8192) || size > substream->dma_max) { |
201 | buffer->error = -EINVAL; | |
dd0da75b | 202 | return; |
1da177e4 LT |
203 | } |
204 | if (substream->dma_buffer.bytes == size) | |
dd0da75b | 205 | return; |
1da177e4 LT |
206 | memset(&new_dmab, 0, sizeof(new_dmab)); |
207 | new_dmab.dev = substream->dma_buffer.dev; | |
208 | if (size > 0) { | |
d4cfb30f TI |
209 | if (do_alloc_pages(card, |
210 | substream->dma_buffer.dev.type, | |
211 | substream->dma_buffer.dev.dev, | |
a25684a9 | 212 | substream->stream, |
d4cfb30f | 213 | size, &new_dmab) < 0) { |
1da177e4 | 214 | buffer->error = -ENOMEM; |
3606f92d | 215 | pr_debug("ALSA pcmC%dD%d%c,%d:%s: cannot preallocate for size %lu\n", |
dc85fc9d AS |
216 | substream->pcm->card->number, substream->pcm->device, |
217 | substream->stream ? 'c' : 'p', substream->number, | |
218 | substream->pcm->name, size); | |
dd0da75b | 219 | return; |
1da177e4 LT |
220 | } |
221 | substream->buffer_bytes_max = size; | |
222 | } else { | |
223 | substream->buffer_bytes_max = UINT_MAX; | |
224 | } | |
225 | if (substream->dma_buffer.area) | |
d4cfb30f | 226 | do_free_pages(card, &substream->dma_buffer); |
1da177e4 LT |
227 | substream->dma_buffer = new_dmab; |
228 | } else { | |
229 | buffer->error = -EINVAL; | |
230 | } | |
231 | } | |
232 | ||
e28563cc | 233 | static inline void preallocate_info_init(struct snd_pcm_substream *substream) |
1da177e4 | 234 | { |
877211f5 | 235 | struct snd_info_entry *entry; |
1da177e4 | 236 | |
a8d14981 TI |
237 | entry = snd_info_create_card_entry(substream->pcm->card, "prealloc", |
238 | substream->proc_root); | |
239 | if (entry) { | |
240 | snd_info_set_text_ops(entry, substream, | |
241 | snd_pcm_lib_preallocate_proc_read); | |
1da177e4 | 242 | entry->c.text.write = snd_pcm_lib_preallocate_proc_write; |
6a73cf46 | 243 | entry->mode |= 0200; |
c7132aeb | 244 | } |
a8d14981 TI |
245 | entry = snd_info_create_card_entry(substream->pcm->card, "prealloc_max", |
246 | substream->proc_root); | |
247 | if (entry) | |
248 | snd_info_set_text_ops(entry, substream, | |
249 | snd_pcm_lib_preallocate_max_proc_read); | |
e28563cc TI |
250 | } |
251 | ||
b7d90a35 | 252 | #else /* !CONFIG_SND_VERBOSE_PROCFS */ |
940ba1f5 AB |
253 | static inline void preallocate_info_init(struct snd_pcm_substream *substream) |
254 | { | |
255 | } | |
b7d90a35 | 256 | #endif /* CONFIG_SND_VERBOSE_PROCFS */ |
e28563cc TI |
257 | |
258 | /* | |
259 | * pre-allocate the buffer and create a proc file for the substream | |
260 | */ | |
ac9245a5 | 261 | static int preallocate_pages(struct snd_pcm_substream *substream, |
0dba808e TI |
262 | int type, struct device *data, |
263 | size_t size, size_t max, bool managed) | |
e28563cc | 264 | { |
ac9245a5 TI |
265 | int err; |
266 | ||
0dba808e | 267 | if (snd_BUG_ON(substream->dma_buffer.dev.type)) |
ac9245a5 | 268 | return -EINVAL; |
0dba808e TI |
269 | |
270 | substream->dma_buffer.dev.type = type; | |
271 | substream->dma_buffer.dev.dev = data; | |
e28563cc | 272 | |
ac9245a5 TI |
273 | if (size > 0) { |
274 | if (!max) { | |
275 | /* no fallback, only also inform -ENOMEM */ | |
276 | err = preallocate_pcm_pages(substream, size, true); | |
277 | if (err < 0) | |
278 | return err; | |
279 | } else if (preallocate_dma && | |
280 | substream->number < maximum_substreams) { | |
281 | err = preallocate_pcm_pages(substream, size, false); | |
282 | if (err < 0 && err != -ENOMEM) | |
283 | return err; | |
284 | } | |
285 | } | |
e28563cc TI |
286 | |
287 | if (substream->dma_buffer.bytes > 0) | |
288 | substream->buffer_bytes_max = substream->dma_buffer.bytes; | |
289 | substream->dma_max = max; | |
d3978991 TI |
290 | if (max > 0) |
291 | preallocate_info_init(substream); | |
0dba808e TI |
292 | if (managed) |
293 | substream->managed_buffer_alloc = 1; | |
ac9245a5 | 294 | return 0; |
1da177e4 LT |
295 | } |
296 | ||
ac9245a5 | 297 | static int preallocate_pages_for_all(struct snd_pcm *pcm, int type, |
0dba808e TI |
298 | void *data, size_t size, size_t max, |
299 | bool managed) | |
300 | { | |
301 | struct snd_pcm_substream *substream; | |
ac9245a5 | 302 | int stream, err; |
0dba808e | 303 | |
ac9245a5 TI |
304 | for_each_pcm_substream(pcm, stream, substream) { |
305 | err = preallocate_pages(substream, type, data, size, max, managed); | |
306 | if (err < 0) | |
307 | return err; | |
308 | } | |
309 | return 0; | |
0dba808e | 310 | } |
1da177e4 LT |
311 | |
312 | /** | |
313 | * snd_pcm_lib_preallocate_pages - pre-allocation for the given DMA type | |
314 | * @substream: the pcm substream instance | |
315 | * @type: DMA type (SNDRV_DMA_TYPE_*) | |
25985edc | 316 | * @data: DMA type dependent data |
1da177e4 LT |
317 | * @size: the requested pre-allocation size in bytes |
318 | * @max: the max. allowed pre-allocation size | |
319 | * | |
320 | * Do pre-allocation for the given DMA buffer type. | |
1da177e4 | 321 | */ |
bb580602 | 322 | void snd_pcm_lib_preallocate_pages(struct snd_pcm_substream *substream, |
1da177e4 LT |
323 | int type, struct device *data, |
324 | size_t size, size_t max) | |
325 | { | |
0dba808e | 326 | preallocate_pages(substream, type, data, size, max, false); |
1da177e4 | 327 | } |
e88e8ae6 TI |
328 | EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages); |
329 | ||
1da177e4 | 330 | /** |
25985edc | 331 | * snd_pcm_lib_preallocate_pages_for_all - pre-allocation for continuous memory type (all substreams) |
df8db936 | 332 | * @pcm: the pcm instance |
1da177e4 | 333 | * @type: DMA type (SNDRV_DMA_TYPE_*) |
25985edc | 334 | * @data: DMA type dependent data |
1da177e4 LT |
335 | * @size: the requested pre-allocation size in bytes |
336 | * @max: the max. allowed pre-allocation size | |
337 | * | |
338 | * Do pre-allocation to all substreams of the given pcm for the | |
339 | * specified DMA type. | |
1da177e4 | 340 | */ |
bb580602 | 341 | void snd_pcm_lib_preallocate_pages_for_all(struct snd_pcm *pcm, |
1da177e4 LT |
342 | int type, void *data, |
343 | size_t size, size_t max) | |
344 | { | |
0dba808e | 345 | preallocate_pages_for_all(pcm, type, data, size, max, false); |
1da177e4 | 346 | } |
e88e8ae6 TI |
347 | EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages_for_all); |
348 | ||
0dba808e TI |
349 | /** |
350 | * snd_pcm_set_managed_buffer - set up buffer management for a substream | |
351 | * @substream: the pcm substream instance | |
352 | * @type: DMA type (SNDRV_DMA_TYPE_*) | |
353 | * @data: DMA type dependent data | |
354 | * @size: the requested pre-allocation size in bytes | |
355 | * @max: the max. allowed pre-allocation size | |
356 | * | |
357 | * Do pre-allocation for the given DMA buffer type, and set the managed | |
358 | * buffer allocation mode to the given substream. | |
359 | * In this mode, PCM core will allocate a buffer automatically before PCM | |
360 | * hw_params ops call, and release the buffer after PCM hw_free ops call | |
361 | * as well, so that the driver doesn't need to invoke the allocation and | |
362 | * the release explicitly in its callback. | |
363 | * When a buffer is actually allocated before the PCM hw_params call, it | |
364 | * turns on the runtime buffer_changed flag for drivers changing their h/w | |
365 | * parameters accordingly. | |
ac9245a5 TI |
366 | * |
367 | * When @size is non-zero and @max is zero, this tries to allocate for only | |
368 | * the exact buffer size without fallback, and may return -ENOMEM. | |
369 | * Otherwise, the function tries to allocate smaller chunks if the allocation | |
370 | * fails. This is the behavior of snd_pcm_set_fixed_buffer(). | |
371 | * | |
372 | * When both @size and @max are zero, the function only sets up the buffer | |
373 | * for later dynamic allocations. It's used typically for buffers with | |
374 | * SNDRV_DMA_TYPE_VMALLOC type. | |
375 | * | |
376 | * Upon successful buffer allocation and setup, the function returns 0. | |
4e2b7067 TI |
377 | * |
378 | * Return: zero if successful, or a negative error code | |
0dba808e | 379 | */ |
ac9245a5 | 380 | int snd_pcm_set_managed_buffer(struct snd_pcm_substream *substream, int type, |
0dba808e TI |
381 | struct device *data, size_t size, size_t max) |
382 | { | |
ac9245a5 | 383 | return preallocate_pages(substream, type, data, size, max, true); |
0dba808e TI |
384 | } |
385 | EXPORT_SYMBOL(snd_pcm_set_managed_buffer); | |
386 | ||
387 | /** | |
388 | * snd_pcm_set_managed_buffer_all - set up buffer management for all substreams | |
389 | * for all substreams | |
390 | * @pcm: the pcm instance | |
391 | * @type: DMA type (SNDRV_DMA_TYPE_*) | |
392 | * @data: DMA type dependent data | |
393 | * @size: the requested pre-allocation size in bytes | |
394 | * @max: the max. allowed pre-allocation size | |
395 | * | |
396 | * Do pre-allocation to all substreams of the given pcm for the specified DMA | |
397 | * type and size, and set the managed_buffer_alloc flag to each substream. | |
4e2b7067 TI |
398 | * |
399 | * Return: zero if successful, or a negative error code | |
0dba808e | 400 | */ |
ac9245a5 TI |
401 | int snd_pcm_set_managed_buffer_all(struct snd_pcm *pcm, int type, |
402 | struct device *data, | |
403 | size_t size, size_t max) | |
0dba808e | 404 | { |
ac9245a5 | 405 | return preallocate_pages_for_all(pcm, type, data, size, max, true); |
0dba808e TI |
406 | } |
407 | EXPORT_SYMBOL(snd_pcm_set_managed_buffer_all); | |
408 | ||
1da177e4 LT |
409 | /** |
410 | * snd_pcm_lib_malloc_pages - allocate the DMA buffer | |
411 | * @substream: the substream to allocate the DMA buffer to | |
412 | * @size: the requested buffer size in bytes | |
413 | * | |
414 | * Allocates the DMA buffer on the BUS type given earlier to | |
415 | * snd_pcm_lib_preallocate_xxx_pages(). | |
416 | * | |
eb7c06e8 | 417 | * Return: 1 if the buffer is changed, 0 if not changed, or a negative |
1da177e4 LT |
418 | * code on failure. |
419 | */ | |
877211f5 | 420 | int snd_pcm_lib_malloc_pages(struct snd_pcm_substream *substream, size_t size) |
1da177e4 | 421 | { |
b658cbab | 422 | struct snd_card *card; |
877211f5 | 423 | struct snd_pcm_runtime *runtime; |
1da177e4 LT |
424 | struct snd_dma_buffer *dmab = NULL; |
425 | ||
7eaa943c TI |
426 | if (PCM_RUNTIME_CHECK(substream)) |
427 | return -EINVAL; | |
428 | if (snd_BUG_ON(substream->dma_buffer.dev.type == | |
429 | SNDRV_DMA_TYPE_UNKNOWN)) | |
430 | return -EINVAL; | |
1da177e4 | 431 | runtime = substream->runtime; |
b658cbab | 432 | card = substream->pcm->card; |
1da177e4 LT |
433 | |
434 | if (runtime->dma_buffer_p) { | |
435 | /* perphaps, we might free the large DMA memory region | |
436 | to save some space here, but the actual solution | |
437 | costs us less time */ | |
438 | if (runtime->dma_buffer_p->bytes >= size) { | |
439 | runtime->dma_bytes = size; | |
440 | return 0; /* ok, do not change */ | |
441 | } | |
442 | snd_pcm_lib_free_pages(substream); | |
443 | } | |
877211f5 TI |
444 | if (substream->dma_buffer.area != NULL && |
445 | substream->dma_buffer.bytes >= size) { | |
1da177e4 LT |
446 | dmab = &substream->dma_buffer; /* use the pre-allocated buffer */ |
447 | } else { | |
ac9245a5 TI |
448 | /* dma_max=0 means the fixed size preallocation */ |
449 | if (substream->dma_buffer.area && !substream->dma_max) | |
450 | return -ENOMEM; | |
ca2c0966 | 451 | dmab = kzalloc(sizeof(*dmab), GFP_KERNEL); |
1da177e4 LT |
452 | if (! dmab) |
453 | return -ENOMEM; | |
454 | dmab->dev = substream->dma_buffer.dev; | |
d4cfb30f TI |
455 | if (do_alloc_pages(card, |
456 | substream->dma_buffer.dev.type, | |
457 | substream->dma_buffer.dev.dev, | |
a25684a9 | 458 | substream->stream, |
d4cfb30f | 459 | size, dmab) < 0) { |
1da177e4 | 460 | kfree(dmab); |
dc85fc9d AS |
461 | pr_debug("ALSA pcmC%dD%d%c,%d:%s: cannot preallocate for size %zu\n", |
462 | substream->pcm->card->number, substream->pcm->device, | |
463 | substream->stream ? 'c' : 'p', substream->number, | |
464 | substream->pcm->name, size); | |
1da177e4 LT |
465 | return -ENOMEM; |
466 | } | |
467 | } | |
468 | snd_pcm_set_runtime_buffer(substream, dmab); | |
469 | runtime->dma_bytes = size; | |
470 | return 1; /* area was changed */ | |
471 | } | |
e88e8ae6 TI |
472 | EXPORT_SYMBOL(snd_pcm_lib_malloc_pages); |
473 | ||
1da177e4 LT |
474 | /** |
475 | * snd_pcm_lib_free_pages - release the allocated DMA buffer. | |
476 | * @substream: the substream to release the DMA buffer | |
477 | * | |
478 | * Releases the DMA buffer allocated via snd_pcm_lib_malloc_pages(). | |
479 | * | |
eb7c06e8 | 480 | * Return: Zero if successful, or a negative error code on failure. |
1da177e4 | 481 | */ |
877211f5 | 482 | int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream) |
1da177e4 | 483 | { |
877211f5 | 484 | struct snd_pcm_runtime *runtime; |
1da177e4 | 485 | |
7eaa943c TI |
486 | if (PCM_RUNTIME_CHECK(substream)) |
487 | return -EINVAL; | |
1da177e4 | 488 | runtime = substream->runtime; |
1da177e4 LT |
489 | if (runtime->dma_area == NULL) |
490 | return 0; | |
491 | if (runtime->dma_buffer_p != &substream->dma_buffer) { | |
011b559b CIK |
492 | struct snd_card *card = substream->pcm->card; |
493 | ||
1da177e4 | 494 | /* it's a newly allocated buffer. release it now. */ |
d4cfb30f | 495 | do_free_pages(card, runtime->dma_buffer_p); |
1da177e4 LT |
496 | kfree(runtime->dma_buffer_p); |
497 | } | |
498 | snd_pcm_set_runtime_buffer(substream, NULL); | |
499 | return 0; | |
500 | } | |
e88e8ae6 | 501 | EXPORT_SYMBOL(snd_pcm_lib_free_pages); |