ftrace: Use objtree for C version of recordmcount
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / sound / core / pcm_memory.c
blob917e4055ee30fdc37d6726e8af2f8d4d07506410
1 /*
2 * Digital Audio (PCM) abstract layer
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
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.
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.
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
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>
33 static int preallocate_dma = 1;
34 module_param(preallocate_dma, int, 0444);
35 MODULE_PARM_DESC(preallocate_dma, "Preallocate DMA memory when the PCM devices are initialized.");
37 static int maximum_substreams = 4;
38 module_param(maximum_substreams, int, 0444);
39 MODULE_PARM_DESC(maximum_substreams, "Maximum substreams with preallocated DMA memory.");
41 static const size_t snd_minimum_buffer = 16384;
45 * try to allocate as the large pages as possible.
46 * stores the resultant memory size in *res_size.
48 * the minimum size is snd_minimum_buffer. it should be power of 2.
50 static int preallocate_pcm_pages(struct snd_pcm_substream *substream, size_t size)
52 struct snd_dma_buffer *dmab = &substream->dma_buffer;
53 int err;
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;
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;
78 * release the preallocated buffer if not yet done.
80 static void snd_pcm_lib_preallocate_dma_free(struct snd_pcm_substream *substream)
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;
91 /**
92 * snd_pcm_lib_preallocate_free - release the preallocated buffer of the specified substream.
93 * @substream: the pcm substream instance
95 * Releases the pre-allocated buffer of the given substream.
97 * Returns zero if successful, or a negative error code on failure.
99 int snd_pcm_lib_preallocate_free(struct snd_pcm_substream *substream)
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;
112 * snd_pcm_lib_preallocate_free_for_all - release all pre-allocated buffers on the pcm
113 * @pcm: the pcm instance
115 * Releases all the pre-allocated buffers on the given pcm.
117 * Returns zero if successful, or a negative error code on failure.
119 int snd_pcm_lib_preallocate_free_for_all(struct snd_pcm *pcm)
121 struct snd_pcm_substream *substream;
122 int stream;
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;
130 EXPORT_SYMBOL(snd_pcm_lib_preallocate_free_for_all);
132 #ifdef CONFIG_SND_VERBOSE_PROCFS
134 * read callback for prealloc proc file
136 * prints the current allocated size in kB.
138 static void snd_pcm_lib_preallocate_proc_read(struct snd_info_entry *entry,
139 struct snd_info_buffer *buffer)
141 struct snd_pcm_substream *substream = entry->private_data;
142 snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_buffer.bytes / 1024);
146 * read callback for prealloc_max proc file
148 * prints the maximum allowed size in kB.
150 static void snd_pcm_lib_preallocate_max_proc_read(struct snd_info_entry *entry,
151 struct snd_info_buffer *buffer)
153 struct snd_pcm_substream *substream = entry->private_data;
154 snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_max / 1024);
158 * write callback for prealloc proc file
160 * accepts the preallocation size in kB.
162 static void snd_pcm_lib_preallocate_proc_write(struct snd_info_entry *entry,
163 struct snd_info_buffer *buffer)
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;
170 if (substream->runtime) {
171 buffer->error = -EBUSY;
172 return;
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;
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;
192 substream->buffer_bytes_max = size;
193 } else {
194 substream->buffer_bytes_max = UINT_MAX;
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;
204 static inline void preallocate_info_init(struct snd_pcm_substream *substream)
206 struct snd_info_entry *entry;
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;
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;
227 substream->proc_prealloc_max_entry = entry;
230 #else /* !CONFIG_SND_VERBOSE_PROCFS */
231 #define preallocate_info_init(s)
232 #endif /* CONFIG_SND_VERBOSE_PROCFS */
235 * pre-allocate the buffer and create a proc file for the substream
237 static int snd_pcm_lib_preallocate_pages1(struct snd_pcm_substream *substream,
238 size_t size, size_t max)
241 if (size > 0 && preallocate_dma && substream->number < maximum_substreams)
242 preallocate_pcm_pages(substream, size);
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;
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 dependant data
257 * @size: the requested pre-allocation size in bytes
258 * @max: the max. allowed pre-allocation size
260 * Do pre-allocation for the given DMA buffer type.
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().
267 * Returns zero if successful, or a negative error code on failure.
269 int snd_pcm_lib_preallocate_pages(struct snd_pcm_substream *substream,
270 int type, struct device *data,
271 size_t size, size_t max)
273 substream->dma_buffer.dev.type = type;
274 substream->dma_buffer.dev.dev = data;
275 return snd_pcm_lib_preallocate_pages1(substream, size, max);
278 EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages);
281 * snd_pcm_lib_preallocate_pages_for_all - pre-allocation for continous memory type (all substreams)
282 * @pcm: the pcm instance
283 * @type: DMA type (SNDRV_DMA_TYPE_*)
284 * @data: DMA type dependant data
285 * @size: the requested pre-allocation size in bytes
286 * @max: the max. allowed pre-allocation size
288 * Do pre-allocation to all substreams of the given pcm for the
289 * specified DMA type.
291 * Returns zero if successful, or a negative error code on failure.
293 int snd_pcm_lib_preallocate_pages_for_all(struct snd_pcm *pcm,
294 int type, void *data,
295 size_t size, size_t max)
297 struct snd_pcm_substream *substream;
298 int stream, err;
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;
307 EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages_for_all);
309 #ifdef CONFIG_SND_DMA_SGBUF
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
315 * Returns the page struct at the given buffer offset.
316 * Used as the page callback of PCM ops.
318 struct page *snd_pcm_sgbuf_ops_page(struct snd_pcm_substream *substream, unsigned long offset)
320 struct snd_sg_buf *sgbuf = snd_pcm_substream_sgbuf(substream);
322 unsigned int idx = offset >> PAGE_SHIFT;
323 if (idx >= (unsigned int)sgbuf->pages)
324 return NULL;
325 return sgbuf->page_table[idx];
328 EXPORT_SYMBOL(snd_pcm_sgbuf_ops_page);
331 * compute the max chunk size with continuous pages on sg-buffer
333 unsigned int snd_pcm_sgbuf_get_chunk_size(struct snd_pcm_substream *substream,
334 unsigned int ofs, unsigned int size)
336 struct snd_sg_buf *sg = snd_pcm_substream_sgbuf(substream);
337 unsigned int start, end, pg;
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;
351 /* ok, all on continuous pages */
352 return size;
354 EXPORT_SYMBOL(snd_pcm_sgbuf_get_chunk_size);
355 #endif /* CONFIG_SND_DMA_SGBUF */
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
362 * Allocates the DMA buffer on the BUS type given earlier to
363 * snd_pcm_lib_preallocate_xxx_pages().
365 * Returns 1 if the buffer is changed, 0 if not changed, or a negative
366 * code on failure.
368 int snd_pcm_lib_malloc_pages(struct snd_pcm_substream *substream, size_t size)
370 struct snd_pcm_runtime *runtime;
371 struct snd_dma_buffer *dmab = NULL;
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;
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 */
388 snd_pcm_lib_free_pages(substream);
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;
405 snd_pcm_set_runtime_buffer(substream, dmab);
406 runtime->dma_bytes = size;
407 return 1; /* area was changed */
410 EXPORT_SYMBOL(snd_pcm_lib_malloc_pages);
413 * snd_pcm_lib_free_pages - release the allocated DMA buffer.
414 * @substream: the substream to release the DMA buffer
416 * Releases the DMA buffer allocated via snd_pcm_lib_malloc_pages().
418 * Returns zero if successful, or a negative error code on failure.
420 int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream)
422 struct snd_pcm_runtime *runtime;
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);
434 snd_pcm_set_runtime_buffer(substream, NULL);
435 return 0;
438 EXPORT_SYMBOL(snd_pcm_lib_free_pages);
440 int _snd_pcm_lib_alloc_vmalloc_buffer(struct snd_pcm_substream *substream,
441 size_t size, gfp_t gfp_flags)
443 struct snd_pcm_runtime *runtime;
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);
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;
459 EXPORT_SYMBOL(_snd_pcm_lib_alloc_vmalloc_buffer);
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()
466 int snd_pcm_lib_free_vmalloc_buffer(struct snd_pcm_substream *substream)
468 struct snd_pcm_runtime *runtime;
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;
477 EXPORT_SYMBOL(snd_pcm_lib_free_vmalloc_buffer);
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
485 * This function is to be used as the page callback in the PCM ops.
487 struct page *snd_pcm_lib_get_vmalloc_page(struct snd_pcm_substream *substream,
488 unsigned long offset)
490 return vmalloc_to_page(substream->runtime->dma_area + offset);
492 EXPORT_SYMBOL(snd_pcm_lib_get_vmalloc_page);