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memalloc.h
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1 /*
2  * Copyright (c) by Jaroslav Kysela <[email protected]>
3  * Takashi Iwai <[email protected]>
4  *
5  * Generic memory allocators
6  *
7  *
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.
12  *
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.
17  *
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
21  *
22  */
23 
24 #ifndef __SOUND_MEMALLOC_H
25 #define __SOUND_MEMALLOC_H
26 
27 struct device;
28 
29 /*
30  * buffer device info
31  */
33  int type; /* SNDRV_DMA_TYPE_XXX */
34  struct device *dev; /* generic device */
35 };
36 
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_continuous_data(x) ((struct device *)(unsigned long)(x))
41 #endif
42 
43 
44 /*
45  * buffer types
46  */
47 #define SNDRV_DMA_TYPE_UNKNOWN 0 /* not defined */
48 #define SNDRV_DMA_TYPE_CONTINUOUS 1 /* continuous no-DMA memory */
49 #define SNDRV_DMA_TYPE_DEV 2 /* generic device continuous */
50 #ifdef CONFIG_SND_DMA_SGBUF
51 #define SNDRV_DMA_TYPE_DEV_SG 3 /* generic device SG-buffer */
52 #else
53 #define SNDRV_DMA_TYPE_DEV_SG SNDRV_DMA_TYPE_DEV /* no SG-buf support */
54 #endif
55 
56 /*
57  * info for buffer allocation
58  */
60  struct snd_dma_device dev; /* device type */
61  unsigned char *area; /* virtual pointer */
62  dma_addr_t addr; /* physical address */
63  size_t bytes; /* buffer size in bytes */
64  void *private_data; /* private for allocator; don't touch */
65 };
66 
67 #ifdef CONFIG_SND_DMA_SGBUF
68 /*
69  * Scatter-Gather generic device pages
70  */
72  size_t size, struct snd_dma_buffer *dmab,
73  size_t *res_size);
74 int snd_free_sgbuf_pages(struct snd_dma_buffer *dmab);
75 
76 struct snd_sg_page {
77  void *buf;
79 };
80 
81 struct snd_sg_buf {
82  int size; /* allocated byte size */
83  int pages; /* allocated pages */
84  int tblsize; /* allocated table size */
85  struct snd_sg_page *table; /* address table */
86  struct page **page_table; /* page table (for vmap/vunmap) */
87  struct device *dev;
88 };
89 
90 /*
91  * return the pages matching with the given byte size
92  */
93 static inline unsigned int snd_sgbuf_aligned_pages(size_t size)
94 {
95  return (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
96 }
97 
98 /*
99  * return the physical address at the corresponding offset
100  */
101 static inline dma_addr_t snd_sgbuf_get_addr(struct snd_dma_buffer *dmab,
102  size_t offset)
103 {
104  struct snd_sg_buf *sgbuf = dmab->private_data;
105  dma_addr_t addr = sgbuf->table[offset >> PAGE_SHIFT].addr;
106  addr &= PAGE_MASK;
107  return addr + offset % PAGE_SIZE;
108 }
109 
110 /*
111  * return the virtual address at the corresponding offset
112  */
113 static inline void *snd_sgbuf_get_ptr(struct snd_dma_buffer *dmab,
114  size_t offset)
115 {
116  struct snd_sg_buf *sgbuf = dmab->private_data;
117  return sgbuf->table[offset >> PAGE_SHIFT].buf + offset % PAGE_SIZE;
118 }
119 
120 unsigned int snd_sgbuf_get_chunk_size(struct snd_dma_buffer *dmab,
121  unsigned int ofs, unsigned int size);
122 #else
123 /* non-SG versions */
124 static inline dma_addr_t snd_sgbuf_get_addr(struct snd_dma_buffer *dmab,
125  size_t offset)
126 {
127  return dmab->addr + offset;
128 }
129 
130 static inline void *snd_sgbuf_get_ptr(struct snd_dma_buffer *dmab,
131  size_t offset)
132 {
133  return dmab->area + offset;
134 }
135 
136 #define snd_sgbuf_get_chunk_size(dmab, ofs, size) (size)
137 
138 #endif /* CONFIG_SND_DMA_SGBUF */
139 
140 /* allocate/release a buffer */
141 int snd_dma_alloc_pages(int type, struct device *dev, size_t size,
142  struct snd_dma_buffer *dmab);
143 int snd_dma_alloc_pages_fallback(int type, struct device *dev, size_t size,
144  struct snd_dma_buffer *dmab);
145 void snd_dma_free_pages(struct snd_dma_buffer *dmab);
146 
147 /* buffer-preservation managements */
148 
149 #define snd_dma_pci_buf_id(pci) (((unsigned int)(pci)->vendor << 16) | (pci)->device)
150 
151 size_t snd_dma_get_reserved_buf(struct snd_dma_buffer *dmab, unsigned int id);
152 int snd_dma_reserve_buf(struct snd_dma_buffer *dmab, unsigned int id);
153 
154 /* basic memory allocation functions */
155 void *snd_malloc_pages(size_t size, gfp_t gfp_flags);
156 void snd_free_pages(void *ptr, size_t size);
157 
158 #endif /* __SOUND_MEMALLOC_H */
159