[deliverable/linux.git] / sound / core / pcm_memory.c

/*
 *  Digital Audio (PCM) abstract layer
 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 *
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#include <asm/io.h>
#include <linux/time.h>
#include <linux/init.h>
#include <linux/moduleparam.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/info.h>
#include <sound/initval.h>

static int preallocate_dma = 1;
module_param(preallocate_dma, int, 0444);
MODULE_PARM_DESC(preallocate_dma, "Preallocate DMA memory when the PCM devices are initialized.");

static int maximum_substreams = 4;
module_param(maximum_substreams, int, 0444);
MODULE_PARM_DESC(maximum_substreams, "Maximum substreams with preallocated DMA memory.");

static const size_t snd_minimum_buffer = 16384;


/*
 * try to allocate as the large pages as possible.
 * stores the resultant memory size in *res_size.
 *
 * the minimum size is snd_minimum_buffer.  it should be power of 2.
 */
static int preallocate_pcm_pages(struct snd_pcm_substream *substream, size_t size)
{
	struct snd_dma_buffer *dmab = &substream->dma_buffer;
	int err;

	/* already reserved? */
	if (snd_dma_get_reserved_buf(dmab, substream->dma_buf_id) > 0) {
		if (dmab->bytes >= size)
			return 0; /* yes */
		/* no, free the reserved block */
		snd_dma_free_pages(dmab);
		dmab->bytes = 0;
	}

	do {
		if ((err = snd_dma_alloc_pages(dmab->dev.type, dmab->dev.dev,
					       size, dmab)) < 0) {
			if (err != -ENOMEM)
				return err; /* fatal error */
		} else
			return 0;
		size >>= 1;
	} while (size >= snd_minimum_buffer);
	dmab->bytes = 0; /* tell error */
	return 0;
}

/*
 * release the preallocated buffer if not yet done.
 */
static void snd_pcm_lib_preallocate_dma_free(struct snd_pcm_substream *substream)
{
	if (substream->dma_buffer.area == NULL)
		return;
	if (substream->dma_buf_id)
		snd_dma_reserve_buf(&substream->dma_buffer, substream->dma_buf_id);
	else
		snd_dma_free_pages(&substream->dma_buffer);
	substream->dma_buffer.area = NULL;
}

/**
 * snd_pcm_lib_preallocate_free - release the preallocated buffer of the specified substream.
 * @substream: the pcm substream instance
 *
 * Releases the pre-allocated buffer of the given substream.
 *
 * Returns zero if successful, or a negative error code on failure.
 */
int snd_pcm_lib_preallocate_free(struct snd_pcm_substream *substream)
{
	snd_pcm_lib_preallocate_dma_free(substream);
#ifdef CONFIG_SND_VERBOSE_PROCFS
	snd_info_free_entry(substream->proc_prealloc_max_entry);
	substream->proc_prealloc_max_entry = NULL;
	snd_info_free_entry(substream->proc_prealloc_entry);
	substream->proc_prealloc_entry = NULL;
#endif
	return 0;
}

/**
 * snd_pcm_lib_preallocate_free_for_all - release all pre-allocated buffers on the pcm
 * @pcm: the pcm instance
 *
 * Releases all the pre-allocated buffers on the given pcm.
 *
 * Returns zero if successful, or a negative error code on failure.
 */
int snd_pcm_lib_preallocate_free_for_all(struct snd_pcm *pcm)
{
	struct snd_pcm_substream *substream;
	int stream;

	for (stream = 0; stream < 2; stream++)
		for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
			snd_pcm_lib_preallocate_free(substream);
	return 0;
}

EXPORT_SYMBOL(snd_pcm_lib_preallocate_free_for_all);

#ifdef CONFIG_SND_VERBOSE_PROCFS
/*
 * read callback for prealloc proc file
 *
 * prints the current allocated size in kB.
 */
static void snd_pcm_lib_preallocate_proc_read(struct snd_info_entry *entry,
					      struct snd_info_buffer *buffer)
{
	struct snd_pcm_substream *substream = entry->private_data;
	snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_buffer.bytes / 1024);
}

/*
 * read callback for prealloc_max proc file
 *
 * prints the maximum allowed size in kB.
 */
static void snd_pcm_lib_preallocate_max_proc_read(struct snd_info_entry *entry,
						  struct snd_info_buffer *buffer)
{
	struct snd_pcm_substream *substream = entry->private_data;
	snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_max / 1024);
}

/*
 * write callback for prealloc proc file
 *
 * accepts the preallocation size in kB.
 */
static void snd_pcm_lib_preallocate_proc_write(struct snd_info_entry *entry,
					       struct snd_info_buffer *buffer)
{
	struct snd_pcm_substream *substream = entry->private_data;
	char line[64], str[64];
	size_t size;
	struct snd_dma_buffer new_dmab;

	if (substream->runtime) {
		buffer->error = -EBUSY;
		return;
	}
	if (!snd_info_get_line(buffer, line, sizeof(line))) {
		snd_info_get_str(str, line, sizeof(str));
		size = simple_strtoul(str, NULL, 10) * 1024;
		if ((size != 0 && size < 8192) || size > substream->dma_max) {
			buffer->error = -EINVAL;
			return;
		}
		if (substream->dma_buffer.bytes == size)
			return;
		memset(&new_dmab, 0, sizeof(new_dmab));
		new_dmab.dev = substream->dma_buffer.dev;
		if (size > 0) {
			if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
						substream->dma_buffer.dev.dev,
						size, &new_dmab) < 0) {
				buffer->error = -ENOMEM;
				return;
			}
			substream->buffer_bytes_max = size;
		} else {
			substream->buffer_bytes_max = UINT_MAX;
		}
		if (substream->dma_buffer.area)
			snd_dma_free_pages(&substream->dma_buffer);
		substream->dma_buffer = new_dmab;
	} else {
		buffer->error = -EINVAL;
	}
}

static inline void preallocate_info_init(struct snd_pcm_substream *substream)
{
	struct snd_info_entry *entry;

	if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc", substream->proc_root)) != NULL) {
		entry->c.text.read = snd_pcm_lib_preallocate_proc_read;
		entry->c.text.write = snd_pcm_lib_preallocate_proc_write;
		entry->mode |= S_IWUSR;
		entry->private_data = substream;
		if (snd_info_register(entry) < 0) {
			snd_info_free_entry(entry);
			entry = NULL;
		}
	}
	substream->proc_prealloc_entry = entry;
	if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc_max", substream->proc_root)) != NULL) {
		entry->c.text.read = snd_pcm_lib_preallocate_max_proc_read;
		entry->private_data = substream;
		if (snd_info_register(entry) < 0) {
			snd_info_free_entry(entry);
			entry = NULL;
		}
	}
	substream->proc_prealloc_max_entry = entry;
}

#else /* !CONFIG_SND_VERBOSE_PROCFS */
#define preallocate_info_init(s)
#endif /* CONFIG_SND_VERBOSE_PROCFS */

/*
 * pre-allocate the buffer and create a proc file for the substream
 */
static int snd_pcm_lib_preallocate_pages1(struct snd_pcm_substream *substream,
					  size_t size, size_t max)
{

	if (size > 0 && preallocate_dma && substream->number < maximum_substreams)
		preallocate_pcm_pages(substream, size);

	if (substream->dma_buffer.bytes > 0)
		substream->buffer_bytes_max = substream->dma_buffer.bytes;
	substream->dma_max = max;
	preallocate_info_init(substream);
	return 0;
}


/**
 * snd_pcm_lib_preallocate_pages - pre-allocation for the given DMA type
 * @substream: the pcm substream instance
 * @type: DMA type (SNDRV_DMA_TYPE_*)
 * @data: DMA type dependant data
 * @size: the requested pre-allocation size in bytes
 * @max: the max. allowed pre-allocation size
 *
 * Do pre-allocation for the given DMA buffer type.
 *
 * When substream->dma_buf_id is set, the function tries to look for
 * the reserved buffer, and the buffer is not freed but reserved at
 * destruction time.  The dma_buf_id must be unique for all systems
 * (in the same DMA buffer type) e.g. using snd_dma_pci_buf_id().
 *
 * Returns zero if successful, or a negative error code on failure.
 */
int snd_pcm_lib_preallocate_pages(struct snd_pcm_substream *substream,
				  int type, struct device *data,
				  size_t size, size_t max)
{
	substream->dma_buffer.dev.type = type;
	substream->dma_buffer.dev.dev = data;
	return snd_pcm_lib_preallocate_pages1(substream, size, max);
}

EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages);

/**
 * snd_pcm_lib_preallocate_pages_for_all - pre-allocation for continous memory type (all substreams)
 * @pcm: the pcm instance
 * @type: DMA type (SNDRV_DMA_TYPE_*)
 * @data: DMA type dependant data
 * @size: the requested pre-allocation size in bytes
 * @max: the max. allowed pre-allocation size
 *
 * Do pre-allocation to all substreams of the given pcm for the
 * specified DMA type.
 *
 * Returns zero if successful, or a negative error code on failure.
 */
int snd_pcm_lib_preallocate_pages_for_all(struct snd_pcm *pcm,
					  int type, void *data,
					  size_t size, size_t max)
{
	struct snd_pcm_substream *substream;
	int stream, err;

	for (stream = 0; stream < 2; stream++)
		for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
			if ((err = snd_pcm_lib_preallocate_pages(substream, type, data, size, max)) < 0)
				return err;
	return 0;
}

EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages_for_all);

/**
 * snd_pcm_sgbuf_ops_page - get the page struct at the given offset
 * @substream: the pcm substream instance
 * @offset: the buffer offset
 *
 * Returns the page struct at the given buffer offset.
 * Used as the page callback of PCM ops.
 */
struct page *snd_pcm_sgbuf_ops_page(struct snd_pcm_substream *substream, unsigned long offset)
{
	struct snd_sg_buf *sgbuf = snd_pcm_substream_sgbuf(substream);

	unsigned int idx = offset >> PAGE_SHIFT;
	if (idx >= (unsigned int)sgbuf->pages)
		return NULL;
	return sgbuf->page_table[idx];
}

EXPORT_SYMBOL(snd_pcm_sgbuf_ops_page);

/*
 * compute the max chunk size with continuous pages on sg-buffer
 */
unsigned int snd_pcm_sgbuf_get_chunk_size(struct snd_pcm_substream *substream,
					  unsigned int ofs, unsigned int size)
{
	struct snd_sg_buf *sg = snd_pcm_substream_sgbuf(substream);
	unsigned int start, end, pg;

	start = ofs >> PAGE_SHIFT;
	end = (ofs + size - 1) >> PAGE_SHIFT;
	/* check page continuity */
	pg = sg->table[start].addr >> PAGE_SHIFT;
	for (;;) {
		start++;
		if (start > end)
			break;
		pg++;
		if ((sg->table[start].addr >> PAGE_SHIFT) != pg)
			return (start << PAGE_SHIFT) - ofs;
	}
	/* ok, all on continuous pages */
	return size;
}
EXPORT_SYMBOL(snd_pcm_sgbuf_get_chunk_size);

/**
 * snd_pcm_lib_malloc_pages - allocate the DMA buffer
 * @substream: the substream to allocate the DMA buffer to
 * @size: the requested buffer size in bytes
 *
 * Allocates the DMA buffer on the BUS type given earlier to
 * snd_pcm_lib_preallocate_xxx_pages().
 *
 * Returns 1 if the buffer is changed, 0 if not changed, or a negative
 * code on failure.
 */
int snd_pcm_lib_malloc_pages(struct snd_pcm_substream *substream, size_t size)
{
	struct snd_pcm_runtime *runtime;
	struct snd_dma_buffer *dmab = NULL;

	if (PCM_RUNTIME_CHECK(substream))
		return -EINVAL;
	if (snd_BUG_ON(substream->dma_buffer.dev.type ==
		       SNDRV_DMA_TYPE_UNKNOWN))
		return -EINVAL;
	runtime = substream->runtime;

	if (runtime->dma_buffer_p) {
		/* perphaps, we might free the large DMA memory region
		   to save some space here, but the actual solution
		   costs us less time */
		if (runtime->dma_buffer_p->bytes >= size) {
			runtime->dma_bytes = size;
			return 0;	/* ok, do not change */
		}
		snd_pcm_lib_free_pages(substream);
	}
	if (substream->dma_buffer.area != NULL &&
	    substream->dma_buffer.bytes >= size) {
		dmab = &substream->dma_buffer; /* use the pre-allocated buffer */
	} else {
		dmab = kzalloc(sizeof(*dmab), GFP_KERNEL);
		if (! dmab)
			return -ENOMEM;
		dmab->dev = substream->dma_buffer.dev;
		if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
					substream->dma_buffer.dev.dev,
					size, dmab) < 0) {
			kfree(dmab);
			return -ENOMEM;
		}
	}
	snd_pcm_set_runtime_buffer(substream, dmab);
	runtime->dma_bytes = size;
	return 1;			/* area was changed */
}

EXPORT_SYMBOL(snd_pcm_lib_malloc_pages);

/**
 * snd_pcm_lib_free_pages - release the allocated DMA buffer.
 * @substream: the substream to release the DMA buffer
 *
 * Releases the DMA buffer allocated via snd_pcm_lib_malloc_pages().
 *
 * Returns zero if successful, or a negative error code on failure.
 */
int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime;

	if (PCM_RUNTIME_CHECK(substream))
		return -EINVAL;
	runtime = substream->runtime;
	if (runtime->dma_area == NULL)
		return 0;
	if (runtime->dma_buffer_p != &substream->dma_buffer) {
		/* it's a newly allocated buffer.  release it now. */
		snd_dma_free_pages(runtime->dma_buffer_p);
		kfree(runtime->dma_buffer_p);
	}
	snd_pcm_set_runtime_buffer(substream, NULL);
	return 0;
}

EXPORT_SYMBOL(snd_pcm_lib_free_pages);
Commit	Line	Data
1da177e4 LT	1	/*
1da177e4 LT	2	* Digital Audio (PCM) abstract layer
c1017a4c	3	* Copyright (c) by Jaroslav Kysela <perex@perex.cz>
1da177e4 LT	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
1da177e4 LT	22	#include <asm/io.h>
	23	#include <linux/time.h>
	24	#include <linux/init.h>
	25	#include <linux/moduleparam.h>
	26	#include <sound/core.h>
	27	#include <sound/pcm.h>
	28	#include <sound/info.h>
	29	#include <sound/initval.h>
	30
	31	static int preallocate_dma = 1;
	32	module_param(preallocate_dma, int, 0444);
	33	MODULE_PARM_DESC(preallocate_dma, "Preallocate DMA memory when the PCM devices are initialized.");
	34
	35	static int maximum_substreams = 4;
	36	module_param(maximum_substreams, int, 0444);
	37	MODULE_PARM_DESC(maximum_substreams, "Maximum substreams with preallocated DMA memory.");
	38
	39	static const size_t snd_minimum_buffer = 16384;
	40
	41
	42	/*
	43	* try to allocate as the large pages as possible.
	44	* stores the resultant memory size in *res_size.
	45	*
	46	* the minimum size is snd_minimum_buffer. it should be power of 2.
	47	*/
877211f5	48	static int preallocate_pcm_pages(struct snd_pcm_substream *substream, size_t size)
1da177e4 LT	49	{
	50	struct snd_dma_buffer *dmab = &substream->dma_buffer;
	51	int err;
	52
1da177e4 LT	53	/* already reserved? */
	54	if (snd_dma_get_reserved_buf(dmab, substream->dma_buf_id) > 0) {
	55	if (dmab->bytes >= size)
	56	return 0; /* yes */
	57	/* no, free the reserved block */
	58	snd_dma_free_pages(dmab);
	59	dmab->bytes = 0;
	60	}
	61
	62	do {
	63	if ((err = snd_dma_alloc_pages(dmab->dev.type, dmab->dev.dev,
	64	size, dmab)) < 0) {
	65	if (err != -ENOMEM)
	66	return err; /* fatal error */
	67	} else
	68	return 0;
	69	size >>= 1;
	70	} while (size >= snd_minimum_buffer);
	71	dmab->bytes = 0; /* tell error */
	72	return 0;
	73	}
	74
	75	/*
	76	* release the preallocated buffer if not yet done.
	77	*/
877211f5	78	static void snd_pcm_lib_preallocate_dma_free(struct snd_pcm_substream *substream)
1da177e4 LT	79	{
	80	if (substream->dma_buffer.area == NULL)
	81	return;
	82	if (substream->dma_buf_id)
	83	snd_dma_reserve_buf(&substream->dma_buffer, substream->dma_buf_id);
	84	else
	85	snd_dma_free_pages(&substream->dma_buffer);
	86	substream->dma_buffer.area = NULL;
	87	}
	88
	89	/**
	90	* snd_pcm_lib_preallocate_free - release the preallocated buffer of the specified substream.
	91	* @substream: the pcm substream instance
	92	*
	93	* Releases the pre-allocated buffer of the given substream.
	94	*
	95	* Returns zero if successful, or a negative error code on failure.
	96	*/
877211f5	97	int snd_pcm_lib_preallocate_free(struct snd_pcm_substream *substream)
1da177e4 LT	98	{
1da177e4 LT	99	snd_pcm_lib_preallocate_dma_free(substream);
b7d90a35	100	#ifdef CONFIG_SND_VERBOSE_PROCFS
c7132aeb JK	101	snd_info_free_entry(substream->proc_prealloc_max_entry);
c7132aeb JK	102	substream->proc_prealloc_max_entry = NULL;
746d4a02	103	snd_info_free_entry(substream->proc_prealloc_entry);
e28563cc	104	substream->proc_prealloc_entry = NULL;
b7d90a35	105	#endif
1da177e4 LT	106	return 0;
	107	}
	108
	109	/**
	110	* snd_pcm_lib_preallocate_free_for_all - release all pre-allocated buffers on the pcm
	111	* @pcm: the pcm instance
	112	*
	113	* Releases all the pre-allocated buffers on the given pcm.
	114	*
	115	* Returns zero if successful, or a negative error code on failure.
	116	*/
877211f5	117	int snd_pcm_lib_preallocate_free_for_all(struct snd_pcm *pcm)
1da177e4	118	{
877211f5	119	struct snd_pcm_substream *substream;
1da177e4 LT	120	int stream;
	121
	122	for (stream = 0; stream < 2; stream++)
	123	for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
	124	snd_pcm_lib_preallocate_free(substream);
	125	return 0;
	126	}
	127
e88e8ae6 TI	128	EXPORT_SYMBOL(snd_pcm_lib_preallocate_free_for_all);
e88e8ae6 TI	129
b7d90a35	130	#ifdef CONFIG_SND_VERBOSE_PROCFS
1da177e4 LT	131	/*
	132	* read callback for prealloc proc file
	133	*
	134	* prints the current allocated size in kB.
	135	*/
877211f5 TI	136	static void snd_pcm_lib_preallocate_proc_read(struct snd_info_entry *entry,
877211f5 TI	137	struct snd_info_buffer *buffer)
1da177e4	138	{
877211f5	139	struct snd_pcm_substream *substream = entry->private_data;
1da177e4 LT	140	snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_buffer.bytes / 1024);
	141	}
	142
c7132aeb JK	143	/*
	144	* read callback for prealloc_max proc file
	145	*
	146	* prints the maximum allowed size in kB.
	147	*/
	148	static void snd_pcm_lib_preallocate_max_proc_read(struct snd_info_entry *entry,
	149	struct snd_info_buffer *buffer)
	150	{
	151	struct snd_pcm_substream *substream = entry->private_data;
	152	snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_max / 1024);
	153	}
	154
1da177e4 LT	155	/*
	156	* write callback for prealloc proc file
	157	*
	158	* accepts the preallocation size in kB.
	159	*/
877211f5 TI	160	static void snd_pcm_lib_preallocate_proc_write(struct snd_info_entry *entry,
877211f5 TI	161	struct snd_info_buffer *buffer)
1da177e4	162	{
877211f5	163	struct snd_pcm_substream *substream = entry->private_data;
1da177e4 LT	164	char line[64], str[64];
	165	size_t size;
	166	struct snd_dma_buffer new_dmab;
	167
	168	if (substream->runtime) {
	169	buffer->error = -EBUSY;
	170	return;
	171	}
	172	if (!snd_info_get_line(buffer, line, sizeof(line))) {
	173	snd_info_get_str(str, line, sizeof(str));
	174	size = simple_strtoul(str, NULL, 10) * 1024;
	175	if ((size != 0 && size < 8192) \|\| size > substream->dma_max) {
	176	buffer->error = -EINVAL;
	177	return;
	178	}
	179	if (substream->dma_buffer.bytes == size)
	180	return;
	181	memset(&new_dmab, 0, sizeof(new_dmab));
	182	new_dmab.dev = substream->dma_buffer.dev;
	183	if (size > 0) {
	184	if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
	185	substream->dma_buffer.dev.dev,
	186	size, &new_dmab) < 0) {
	187	buffer->error = -ENOMEM;
	188	return;
	189	}
	190	substream->buffer_bytes_max = size;
	191	} else {
	192	substream->buffer_bytes_max = UINT_MAX;
	193	}
	194	if (substream->dma_buffer.area)
	195	snd_dma_free_pages(&substream->dma_buffer);
	196	substream->dma_buffer = new_dmab;
	197	} else {
	198	buffer->error = -EINVAL;
	199	}
	200	}
	201
e28563cc	202	static inline void preallocate_info_init(struct snd_pcm_substream *substream)
1da177e4	203	{
877211f5	204	struct snd_info_entry *entry;
1da177e4	205
1da177e4	206	if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc", substream->proc_root)) != NULL) {
1da177e4	207	entry->c.text.read = snd_pcm_lib_preallocate_proc_read;
1da177e4	208	entry->c.text.write = snd_pcm_lib_preallocate_proc_write;
bd7bf042	209	entry->mode \|= S_IWUSR;
1da177e4 LT	210	entry->private_data = substream;
	211	if (snd_info_register(entry) < 0) {
	212	snd_info_free_entry(entry);
	213	entry = NULL;
	214	}
	215	}
	216	substream->proc_prealloc_entry = entry;
c7132aeb JK	217	if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc_max", substream->proc_root)) != NULL) {
	218	entry->c.text.read = snd_pcm_lib_preallocate_max_proc_read;
	219	entry->private_data = substream;
	220	if (snd_info_register(entry) < 0) {
	221	snd_info_free_entry(entry);
	222	entry = NULL;
	223	}
	224	}
	225	substream->proc_prealloc_max_entry = entry;
e28563cc TI	226	}
e28563cc TI	227
b7d90a35	228	#else /* !CONFIG_SND_VERBOSE_PROCFS */
e28563cc	229	#define preallocate_info_init(s)
b7d90a35	230	#endif /* CONFIG_SND_VERBOSE_PROCFS */
e28563cc TI	231
	232	/*
	233	* pre-allocate the buffer and create a proc file for the substream
	234	*/
	235	static int snd_pcm_lib_preallocate_pages1(struct snd_pcm_substream *substream,
	236	size_t size, size_t max)
	237	{
	238
	239	if (size > 0 && preallocate_dma && substream->number < maximum_substreams)
	240	preallocate_pcm_pages(substream, size);
	241
	242	if (substream->dma_buffer.bytes > 0)
	243	substream->buffer_bytes_max = substream->dma_buffer.bytes;
	244	substream->dma_max = max;
	245	preallocate_info_init(substream);
1da177e4 LT	246	return 0;
	247	}
	248
	249
	250	/**
	251	* snd_pcm_lib_preallocate_pages - pre-allocation for the given DMA type
	252	* @substream: the pcm substream instance
	253	* @type: DMA type (SNDRV_DMA_TYPE_*)
	254	* @data: DMA type dependant data
	255	* @size: the requested pre-allocation size in bytes
	256	* @max: the max. allowed pre-allocation size
	257	*
	258	* Do pre-allocation for the given DMA buffer type.
	259	*
	260	* When substream->dma_buf_id is set, the function tries to look for
	261	* the reserved buffer, and the buffer is not freed but reserved at
	262	* destruction time. The dma_buf_id must be unique for all systems
	263	* (in the same DMA buffer type) e.g. using snd_dma_pci_buf_id().
	264	*
	265	* Returns zero if successful, or a negative error code on failure.
	266	*/
877211f5	267	int snd_pcm_lib_preallocate_pages(struct snd_pcm_substream *substream,
1da177e4 LT	268	int type, struct device *data,
	269	size_t size, size_t max)
	270	{
	271	substream->dma_buffer.dev.type = type;
	272	substream->dma_buffer.dev.dev = data;
	273	return snd_pcm_lib_preallocate_pages1(substream, size, max);
	274	}
	275
e88e8ae6 TI	276	EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages);
e88e8ae6 TI	277
1da177e4 LT	278	/**
1da177e4 LT	279	* snd_pcm_lib_preallocate_pages_for_all - pre-allocation for continous memory type (all substreams)
df8db936	280	* @pcm: the pcm instance
1da177e4 LT	281	* @type: DMA type (SNDRV_DMA_TYPE_*)
	282	* @data: DMA type dependant data
	283	* @size: the requested pre-allocation size in bytes
	284	* @max: the max. allowed pre-allocation size
	285	*
	286	* Do pre-allocation to all substreams of the given pcm for the
	287	* specified DMA type.
	288	*
	289	* Returns zero if successful, or a negative error code on failure.
	290	*/
877211f5	291	int snd_pcm_lib_preallocate_pages_for_all(struct snd_pcm *pcm,
1da177e4 LT	292	int type, void *data,
	293	size_t size, size_t max)
	294	{
877211f5	295	struct snd_pcm_substream *substream;
1da177e4 LT	296	int stream, err;
	297
	298	for (stream = 0; stream < 2; stream++)
	299	for (substream = pcm->streams[stream].substream; substream; substream = substream->next)
	300	if ((err = snd_pcm_lib_preallocate_pages(substream, type, data, size, max)) < 0)
	301	return err;
	302	return 0;
	303	}
	304
e88e8ae6 TI	305	EXPORT_SYMBOL(snd_pcm_lib_preallocate_pages_for_all);
e88e8ae6 TI	306
1da177e4 LT	307	/**
	308	* snd_pcm_sgbuf_ops_page - get the page struct at the given offset
	309	* @substream: the pcm substream instance
	310	* @offset: the buffer offset
	311	*
	312	* Returns the page struct at the given buffer offset.
	313	* Used as the page callback of PCM ops.
	314	*/
877211f5	315	struct page snd_pcm_sgbuf_ops_page(struct snd_pcm_substream substream, unsigned long offset)
1da177e4 LT	316	{
	317	struct snd_sg_buf *sgbuf = snd_pcm_substream_sgbuf(substream);
	318
	319	unsigned int idx = offset >> PAGE_SHIFT;
	320	if (idx >= (unsigned int)sgbuf->pages)
	321	return NULL;
	322	return sgbuf->page_table[idx];
	323	}
	324
e88e8ae6 TI	325	EXPORT_SYMBOL(snd_pcm_sgbuf_ops_page);
e88e8ae6 TI	326
51e9f2e6 TI	327	/*
	328	* compute the max chunk size with continuous pages on sg-buffer
	329	*/
	330	unsigned int snd_pcm_sgbuf_get_chunk_size(struct snd_pcm_substream *substream,
	331	unsigned int ofs, unsigned int size)
	332	{
	333	struct snd_sg_buf *sg = snd_pcm_substream_sgbuf(substream);
	334	unsigned int start, end, pg;
	335
	336	start = ofs >> PAGE_SHIFT;
	337	end = (ofs + size - 1) >> PAGE_SHIFT;
	338	/* check page continuity */
	339	pg = sg->table[start].addr >> PAGE_SHIFT;
	340	for (;;) {
	341	start++;
	342	if (start > end)
	343	break;
	344	pg++;
	345	if ((sg->table[start].addr >> PAGE_SHIFT) != pg)
	346	return (start << PAGE_SHIFT) - ofs;
	347	}
	348	/* ok, all on continuous pages */
	349	return size;
	350	}
	351	EXPORT_SYMBOL(snd_pcm_sgbuf_get_chunk_size);
	352
1da177e4 LT	353	/**
	354	* snd_pcm_lib_malloc_pages - allocate the DMA buffer
	355	* @substream: the substream to allocate the DMA buffer to
	356	* @size: the requested buffer size in bytes
	357	*
	358	* Allocates the DMA buffer on the BUS type given earlier to
	359	* snd_pcm_lib_preallocate_xxx_pages().
	360	*
	361	* Returns 1 if the buffer is changed, 0 if not changed, or a negative
	362	* code on failure.
	363	*/
877211f5	364	int snd_pcm_lib_malloc_pages(struct snd_pcm_substream *substream, size_t size)
1da177e4	365	{
877211f5	366	struct snd_pcm_runtime *runtime;
1da177e4 LT	367	struct snd_dma_buffer *dmab = NULL;
1da177e4 LT	368
7eaa943c TI	369	if (PCM_RUNTIME_CHECK(substream))
	370	return -EINVAL;
	371	if (snd_BUG_ON(substream->dma_buffer.dev.type ==
	372	SNDRV_DMA_TYPE_UNKNOWN))
	373	return -EINVAL;
1da177e4	374	runtime = substream->runtime;
1da177e4 LT	375
	376	if (runtime->dma_buffer_p) {
	377	/* perphaps, we might free the large DMA memory region
	378	to save some space here, but the actual solution
	379	costs us less time */
	380	if (runtime->dma_buffer_p->bytes >= size) {
	381	runtime->dma_bytes = size;
	382	return 0; /* ok, do not change */
	383	}
	384	snd_pcm_lib_free_pages(substream);
	385	}
877211f5 TI	386	if (substream->dma_buffer.area != NULL &&
877211f5 TI	387	substream->dma_buffer.bytes >= size) {
1da177e4 LT	388	dmab = &substream->dma_buffer; /* use the pre-allocated buffer */
1da177e4 LT	389	} else {
ca2c0966	390	dmab = kzalloc(sizeof(*dmab), GFP_KERNEL);
1da177e4 LT	391	if (! dmab)
	392	return -ENOMEM;
	393	dmab->dev = substream->dma_buffer.dev;
	394	if (snd_dma_alloc_pages(substream->dma_buffer.dev.type,
	395	substream->dma_buffer.dev.dev,
	396	size, dmab) < 0) {
	397	kfree(dmab);
	398	return -ENOMEM;
	399	}
	400	}
	401	snd_pcm_set_runtime_buffer(substream, dmab);
	402	runtime->dma_bytes = size;
	403	return 1; /* area was changed */
	404	}
	405
e88e8ae6 TI	406	EXPORT_SYMBOL(snd_pcm_lib_malloc_pages);
e88e8ae6 TI	407
1da177e4 LT	408	/**
	409	* snd_pcm_lib_free_pages - release the allocated DMA buffer.
	410	* @substream: the substream to release the DMA buffer
	411	*
	412	* Releases the DMA buffer allocated via snd_pcm_lib_malloc_pages().
	413	*
	414	* Returns zero if successful, or a negative error code on failure.
	415	*/
877211f5	416	int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream)
1da177e4	417	{
877211f5	418	struct snd_pcm_runtime *runtime;
1da177e4	419
7eaa943c TI	420	if (PCM_RUNTIME_CHECK(substream))
7eaa943c TI	421	return -EINVAL;
1da177e4	422	runtime = substream->runtime;
1da177e4 LT	423	if (runtime->dma_area == NULL)
	424	return 0;
	425	if (runtime->dma_buffer_p != &substream->dma_buffer) {
	426	/* it's a newly allocated buffer. release it now. */
	427	snd_dma_free_pages(runtime->dma_buffer_p);
	428	kfree(runtime->dma_buffer_p);
	429	}
	430	snd_pcm_set_runtime_buffer(substream, NULL);
	431	return 0;
	432	}
e88e8ae6 TI	433
e88e8ae6 TI	434	EXPORT_SYMBOL(snd_pcm_lib_free_pages);