[PATCH] Get rid of "double zeroing" of allocated pages
[linux-2.6/verdex.git] / include / sound / memalloc.h
blob83489c3abbaf5f048293c4aea3041da63143a879
1 /*
2 * Copyright (c) by Jaroslav Kysela <perex@suse.cz>
3 * Takashi Iwai <tiwai@suse.de>
4 *
5 * Generic memory allocators
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 #ifndef __SOUND_MEMALLOC_H
25 #define __SOUND_MEMALLOC_H
27 struct device;
30 * buffer device info
32 struct snd_dma_device {
33 int type; /* SNDRV_DMA_TYPE_XXX */
34 struct device *dev; /* generic device */
37 #ifndef snd_dma_pci_data
38 #define snd_dma_pci_data(pci) (&(pci)->dev)
39 #define snd_dma_isa_data() NULL
40 #define snd_dma_sbus_data(sbus) ((struct device *)(sbus))
41 #define snd_dma_continuous_data(x) ((struct device *)(unsigned long)(x))
42 #endif
46 * buffer types
48 #define SNDRV_DMA_TYPE_UNKNOWN 0 /* not defined */
49 #define SNDRV_DMA_TYPE_CONTINUOUS 1 /* continuous no-DMA memory */
50 #define SNDRV_DMA_TYPE_DEV 2 /* generic device continuous */
51 #define SNDRV_DMA_TYPE_DEV_SG 3 /* generic device SG-buffer */
52 #define SNDRV_DMA_TYPE_SBUS 4 /* SBUS continuous */
55 * info for buffer allocation
57 struct snd_dma_buffer {
58 struct snd_dma_device dev; /* device type */
59 unsigned char *area; /* virtual pointer */
60 dma_addr_t addr; /* physical address */
61 size_t bytes; /* buffer size in bytes */
62 void *private_data; /* private for allocator; don't touch */
66 * Scatter-Gather generic device pages
68 struct snd_sg_page {
69 void *buf;
70 dma_addr_t addr;
73 struct snd_sg_buf {
74 int size; /* allocated byte size */
75 int pages; /* allocated pages */
76 int tblsize; /* allocated table size */
77 struct snd_sg_page *table; /* address table */
78 struct page **page_table; /* page table (for vmap/vunmap) */
79 struct device *dev;
83 * return the pages matching with the given byte size
85 static inline unsigned int snd_sgbuf_aligned_pages(size_t size)
87 return (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
91 * return the physical address at the corresponding offset
93 static inline dma_addr_t snd_sgbuf_get_addr(struct snd_sg_buf *sgbuf, size_t offset)
95 return sgbuf->table[offset >> PAGE_SHIFT].addr + offset % PAGE_SIZE;
99 /* allocate/release a buffer */
100 int snd_dma_alloc_pages(int type, struct device *dev, size_t size,
101 struct snd_dma_buffer *dmab);
102 int snd_dma_alloc_pages_fallback(int type, struct device *dev, size_t size,
103 struct snd_dma_buffer *dmab);
104 void snd_dma_free_pages(struct snd_dma_buffer *dmab);
106 /* buffer-preservation managements */
108 #define snd_dma_pci_buf_id(pci) (((unsigned int)(pci)->vendor << 16) | (pci)->device)
110 size_t snd_dma_get_reserved_buf(struct snd_dma_buffer *dmab, unsigned int id);
111 int snd_dma_reserve_buf(struct snd_dma_buffer *dmab, unsigned int id);
113 /* basic memory allocation functions */
114 void *snd_malloc_pages(size_t size, gfp_t gfp_flags);
115 void snd_free_pages(void *ptr, size_t size);
117 #endif /* __SOUND_MEMALLOC_H */