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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
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
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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 int err;
55
56
57 if (snd_dma_get_reserved_buf(dmab, substream->dma_buf_id) > 0) {
58 if (dmab->bytes >= size)
59 return 0;
60
61 snd_dma_free_pages(dmab);
62 dmab->bytes = 0;
63 }
64
65 do {
66 if ((err = snd_dma_alloc_pages(dmab->dev.type, dmab->dev.dev,
67 size, dmab)) < 0) {
68 if (err != -ENOMEM)
69 return err;
70 } else
71 return 0;
72 size >>= 1;
73 } while (size >= snd_minimum_buffer);
74 dmab->bytes = 0;
75 return 0;
76}
77
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79
80
81static void snd_pcm_lib_preallocate_dma_free(struct snd_pcm_substream *substream)
82{
83 if (substream->dma_buffer.area == NULL)
84 return;
85 if (substream->dma_buf_id)
86 snd_dma_reserve_buf(&substream->dma_buffer, substream->dma_buf_id);
87 else
88 snd_dma_free_pages(&substream->dma_buffer);
89 substream->dma_buffer.area = NULL;
90}
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99
100int snd_pcm_lib_preallocate_free(struct snd_pcm_substream *substream)
101{
102 snd_pcm_lib_preallocate_dma_free(substream);
103#ifdef CONFIG_SND_VERBOSE_PROCFS
104 snd_info_free_entry(substream->proc_prealloc_max_entry);
105 substream->proc_prealloc_max_entry = NULL;
106 snd_info_free_entry(substream->proc_prealloc_entry);
107 substream->proc_prealloc_entry = NULL;
108#endif
109 return 0;
110}
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119
120int snd_pcm_lib_preallocate_free_for_all(struct snd_pcm *pcm)
121{
122 struct snd_pcm_substream *substream;
123 int stream;
124
125 for (stream = 0; stream < 2; stream++)
126 for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
127 snd_pcm_lib_preallocate_free(substream);
128 return 0;
129}
130
131EXPORT_SYMBOL(snd_pcm_lib_preallocate_free_for_all);
132
133#ifdef CONFIG_SND_VERBOSE_PROCFS
134
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137
138
139static void snd_pcm_lib_preallocate_proc_read(struct snd_info_entry *entry,
140 struct snd_info_buffer *buffer)
141{
142 struct snd_pcm_substream *substream = entry->private_data;
143 snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_buffer.bytes / 1024);
144}
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150
151static void snd_pcm_lib_preallocate_max_proc_read(struct snd_info_entry *entry,
152 struct snd_info_buffer *buffer)
153{
154 struct snd_pcm_substream *substream = entry->private_data;
155 snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_max / 1024);
156}
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162
163static void snd_pcm_lib_preallocate_proc_write(struct snd_info_entry *entry,
164 struct snd_info_buffer *buffer)
165{
166 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 if (substream->runtime) {
172 buffer->error = -EBUSY;
173 return;
174 }
175 if (!snd_info_get_line(buffer, line, sizeof(line))) {
176 snd_info_get_str(str, line, sizeof(str));
177 size = simple_strtoul(str, NULL, 10) * 1024;
178 if ((size != 0 && size < 8192) || size > substream->dma_max) {
179 buffer->error = -EINVAL;
180 return;
181 }
182 if (substream->dma_buffer.bytes == size)
183 return;
184 memset(&new_dmab, 0, sizeof(new_dmab));
185 new_dmab.dev = substream->dma_buffer.dev;
186 if (size > 0) {
187 if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
188 substream->dma_buffer.dev.dev,
189 size, &new_dmab) < 0) {
190 buffer->error = -ENOMEM;
191 return;
192 }
193 substream->buffer_bytes_max = size;
194 } else {
195 substream->buffer_bytes_max = UINT_MAX;
196 }
197 if (substream->dma_buffer.area)
198 snd_dma_free_pages(&substream->dma_buffer);
199 substream->dma_buffer = new_dmab;
200 } else {
201 buffer->error = -EINVAL;
202 }
203}
204
205static inline void preallocate_info_init(struct snd_pcm_substream *substream)
206{
207 struct snd_info_entry *entry;
208
209 if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc", substream->proc_root)) != NULL) {
210 entry->c.text.read = snd_pcm_lib_preallocate_proc_read;
211 entry->c.text.write = snd_pcm_lib_preallocate_proc_write;
212 entry->mode |= S_IWUSR;
213 entry->private_data = substream;
214 if (snd_info_register(entry) < 0) {
215 snd_info_free_entry(entry);
216 entry = NULL;
217 }
218 }
219 substream->proc_prealloc_entry = entry;
220 if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc_max", substream->proc_root)) != NULL) {
221 entry->c.text.read = snd_pcm_lib_preallocate_max_proc_read;
222 entry->private_data = substream;
223 if (snd_info_register(entry) < 0) {
224 snd_info_free_entry(entry);
225 entry = NULL;
226 }
227 }
228 substream->proc_prealloc_max_entry = entry;
229}
230
231#else
232#define preallocate_info_init(s)
233#endif
234
235
236
237
238static int snd_pcm_lib_preallocate_pages1(struct snd_pcm_substream *substream,
239 size_t size, size_t max)
240{
241
242 if (size > 0 && preallocate_dma && substream->number < maximum_substreams)
243 preallocate_pcm_pages(substream, size);
244
245 if (substream->dma_buffer.bytes > 0)
246 substream->buffer_bytes_max = substream->dma_buffer.bytes;
247 substream->dma_max = max;
248 preallocate_info_init(substream);
249 return 0;
250}
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270int 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 substream->dma_buffer.dev.type = type;
275 substream->dma_buffer.dev.dev = data;
276 return snd_pcm_lib_preallocate_pages1(substream, size, max);
277}
278
279EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages);
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294int 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 for (stream = 0; stream < 2; stream++)
302 for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
303 if ((err = snd_pcm_lib_preallocate_pages(substream, type, data, size, max)) < 0)
304 return err;
305 return 0;
306}
307
308EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages_for_all);
309
310#ifdef CONFIG_SND_DMA_SGBUF
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320struct 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
330EXPORT_SYMBOL(snd_pcm_sgbuf_ops_page);
331#endif
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343
344int 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 if (PCM_RUNTIME_CHECK(substream))
350 return -EINVAL;
351 if (snd_BUG_ON(substream->dma_buffer.dev.type ==
352 SNDRV_DMA_TYPE_UNKNOWN))
353 return -EINVAL;
354 runtime = substream->runtime;
355
356 if (runtime->dma_buffer_p) {
357
358
359
360 if (runtime->dma_buffer_p->bytes >= size) {
361 runtime->dma_bytes = size;
362 return 0;
363 }
364 snd_pcm_lib_free_pages(substream);
365 }
366 if (substream->dma_buffer.area != NULL &&
367 substream->dma_buffer.bytes >= size) {
368 dmab = &substream->dma_buffer;
369 } else {
370 dmab = kzalloc(sizeof(*dmab), GFP_KERNEL);
371 if (! dmab)
372 return -ENOMEM;
373 dmab->dev = substream->dma_buffer.dev;
374 if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
375 substream->dma_buffer.dev.dev,
376 size, dmab) < 0) {
377 kfree(dmab);
378 return -ENOMEM;
379 }
380 }
381 snd_pcm_set_runtime_buffer(substream, dmab);
382 runtime->dma_bytes = size;
383 return 1;
384}
385
386EXPORT_SYMBOL(snd_pcm_lib_malloc_pages);
387
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396int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream)
397{
398 struct snd_pcm_runtime *runtime;
399
400 if (PCM_RUNTIME_CHECK(substream))
401 return -EINVAL;
402 runtime = substream->runtime;
403 if (runtime->dma_area == NULL)
404 return 0;
405 if (runtime->dma_buffer_p != &substream->dma_buffer) {
406
407 snd_dma_free_pages(runtime->dma_buffer_p);
408 kfree(runtime->dma_buffer_p);
409 }
410 snd_pcm_set_runtime_buffer(substream, NULL);
411 return 0;
412}
413
414EXPORT_SYMBOL(snd_pcm_lib_free_pages);
415
416int _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 if (PCM_RUNTIME_CHECK(substream))
422 return -EINVAL;
423 runtime = substream->runtime;
424 if (runtime->dma_area) {
425 if (runtime->dma_bytes >= size)
426 return 0;
427 vfree(runtime->dma_area);
428 }
429 runtime->dma_area = __vmalloc(size, gfp_flags, PAGE_KERNEL);
430 if (!runtime->dma_area)
431 return -ENOMEM;
432 runtime->dma_bytes = size;
433 return 1;
434}
435EXPORT_SYMBOL(_snd_pcm_lib_alloc_vmalloc_buffer);
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444int snd_pcm_lib_free_vmalloc_buffer(struct snd_pcm_substream *substream)
445{
446 struct snd_pcm_runtime *runtime;
447
448 if (PCM_RUNTIME_CHECK(substream))
449 return -EINVAL;
450 runtime = substream->runtime;
451 vfree(runtime->dma_area);
452 runtime->dma_area = NULL;
453 return 0;
454}
455EXPORT_SYMBOL(snd_pcm_lib_free_vmalloc_buffer);
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467struct page *snd_pcm_lib_get_vmalloc_page(struct snd_pcm_substream *substream,
468 unsigned long offset)
469{
470 return vmalloc_to_page(substream->runtime->dma_area + offset);
471}
472EXPORT_SYMBOL(snd_pcm_lib_get_vmalloc_page);
473