linux/include/sound/memalloc.h
Takashi Iwai 2a1f3368bf ALSA: memalloc: Make SG-buffer helper usable for continuous buffer, too
We have a few helper functions for making the access to the buffer
address easier on SG-buffer.  Those are specific to the buffer that is
allocated with SG-buffer type, and it makes hard to use both SG and
non-SG buffers in the same code.

This patch adds a few simple checks and lets the helpers to deal with
both SG- and continuous buffers gracefully.  It's a preliminary step
for the upcoming patch that mimics the buffer type on the fly.

Link: https://lore.kernel.org/r/20200615160045.2703-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-06-15 18:01:52 +02:00

148 lines
3.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copyright (c) by Jaroslav Kysela <perex@perex.cz>
* Takashi Iwai <tiwai@suse.de>
*
* Generic memory allocators
*/
#ifndef __SOUND_MEMALLOC_H
#define __SOUND_MEMALLOC_H
#include <asm/page.h>
struct device;
/*
* buffer device info
*/
struct snd_dma_device {
int type; /* SNDRV_DMA_TYPE_XXX */
struct device *dev; /* generic device */
};
#define snd_dma_continuous_data(x) ((struct device *)(__force unsigned long)(x))
/*
* buffer types
*/
#define SNDRV_DMA_TYPE_UNKNOWN 0 /* not defined */
#define SNDRV_DMA_TYPE_CONTINUOUS 1 /* continuous no-DMA memory */
#define SNDRV_DMA_TYPE_DEV 2 /* generic device continuous */
#define SNDRV_DMA_TYPE_DEV_UC 5 /* continuous non-cahced */
#ifdef CONFIG_SND_DMA_SGBUF
#define SNDRV_DMA_TYPE_DEV_SG 3 /* generic device SG-buffer */
#define SNDRV_DMA_TYPE_DEV_UC_SG 6 /* SG non-cached */
#else
#define SNDRV_DMA_TYPE_DEV_SG SNDRV_DMA_TYPE_DEV /* no SG-buf support */
#define SNDRV_DMA_TYPE_DEV_UC_SG SNDRV_DMA_TYPE_DEV_UC
#endif
#ifdef CONFIG_GENERIC_ALLOCATOR
#define SNDRV_DMA_TYPE_DEV_IRAM 4 /* generic device iram-buffer */
#else
#define SNDRV_DMA_TYPE_DEV_IRAM SNDRV_DMA_TYPE_DEV
#endif
#define SNDRV_DMA_TYPE_VMALLOC 7 /* vmalloc'ed buffer */
/*
* info for buffer allocation
*/
struct snd_dma_buffer {
struct snd_dma_device dev; /* device type */
unsigned char *area; /* virtual pointer */
dma_addr_t addr; /* physical address */
size_t bytes; /* buffer size in bytes */
void *private_data; /* private for allocator; don't touch */
};
/*
* return the pages matching with the given byte size
*/
static inline unsigned int snd_sgbuf_aligned_pages(size_t size)
{
return (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
}
#ifdef CONFIG_SND_DMA_SGBUF
/*
* Scatter-Gather generic device pages
*/
void *snd_malloc_sgbuf_pages(struct device *device,
size_t size, struct snd_dma_buffer *dmab,
size_t *res_size);
int snd_free_sgbuf_pages(struct snd_dma_buffer *dmab);
struct snd_sg_page {
void *buf;
dma_addr_t addr;
};
struct snd_sg_buf {
int size; /* allocated byte size */
int pages; /* allocated pages */
int tblsize; /* allocated table size */
struct snd_sg_page *table; /* address table */
struct page **page_table; /* page table (for vmap/vunmap) */
struct device *dev;
};
/*
* return the physical address at the corresponding offset
*/
static inline dma_addr_t snd_sgbuf_get_addr(struct snd_dma_buffer *dmab,
size_t offset)
{
struct snd_sg_buf *sgbuf = dmab->private_data;
dma_addr_t addr;
if (!sgbuf)
return dmab->addr + offset;
addr = sgbuf->table[offset >> PAGE_SHIFT].addr;
addr &= ~((dma_addr_t)PAGE_SIZE - 1);
return addr + offset % PAGE_SIZE;
}
/*
* return the virtual address at the corresponding offset
*/
static inline void *snd_sgbuf_get_ptr(struct snd_dma_buffer *dmab,
size_t offset)
{
struct snd_sg_buf *sgbuf = dmab->private_data;
if (!sgbuf)
return dmab->area + offset;
return sgbuf->table[offset >> PAGE_SHIFT].buf + offset % PAGE_SIZE;
}
unsigned int snd_sgbuf_get_chunk_size(struct snd_dma_buffer *dmab,
unsigned int ofs, unsigned int size);
#else
/* non-SG versions */
static inline dma_addr_t snd_sgbuf_get_addr(struct snd_dma_buffer *dmab,
size_t offset)
{
return dmab->addr + offset;
}
static inline void *snd_sgbuf_get_ptr(struct snd_dma_buffer *dmab,
size_t offset)
{
return dmab->area + offset;
}
#define snd_sgbuf_get_chunk_size(dmab, ofs, size) (size)
#endif /* CONFIG_SND_DMA_SGBUF */
/* allocate/release a buffer */
int snd_dma_alloc_pages(int type, struct device *dev, size_t size,
struct snd_dma_buffer *dmab);
int snd_dma_alloc_pages_fallback(int type, struct device *dev, size_t size,
struct snd_dma_buffer *dmab);
void snd_dma_free_pages(struct snd_dma_buffer *dmab);
#endif /* __SOUND_MEMALLOC_H */