xref: /linux/include/linux/dmapool.h (revision ab93e0dd72c37d378dd936f031ffb83ff2bd87ce)
1 /*
2  * include/linux/dmapool.h
3  *
4  * Allocation pools for DMAable (coherent) memory.
5  *
6  * This file is licensed under  the terms of the GNU General Public
7  * License version 2. This program is licensed "as is" without any
8  * warranty of any kind, whether express or implied.
9  */
10 
11 #ifndef LINUX_DMAPOOL_H
12 #define	LINUX_DMAPOOL_H
13 
14 #include <linux/nodemask_types.h>
15 #include <linux/scatterlist.h>
16 #include <asm/io.h>
17 
18 struct device;
19 
20 #ifdef CONFIG_HAS_DMA
21 
22 struct dma_pool *dma_pool_create_node(const char *name, struct device *dev,
23 		size_t size, size_t align, size_t boundary, int node);
24 
25 void dma_pool_destroy(struct dma_pool *pool);
26 
27 void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags,
28 		     dma_addr_t *handle);
29 void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t addr);
30 
31 /*
32  * Managed DMA pool
33  */
34 struct dma_pool *dmam_pool_create(const char *name, struct device *dev,
35 				  size_t size, size_t align, size_t allocation);
36 void dmam_pool_destroy(struct dma_pool *pool);
37 
38 #else /* !CONFIG_HAS_DMA */
dma_pool_create_node(const char * name,struct device * dev,size_t size,size_t align,size_t boundary,int node)39 static inline struct dma_pool *dma_pool_create_node(const char *name,
40 		struct device *dev, size_t size, size_t align, size_t boundary,
41 		int node)
42 {
43 	return NULL;
44 }
dma_pool_destroy(struct dma_pool * pool)45 static inline void dma_pool_destroy(struct dma_pool *pool) { }
dma_pool_alloc(struct dma_pool * pool,gfp_t mem_flags,dma_addr_t * handle)46 static inline void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags,
47 				   dma_addr_t *handle) { return NULL; }
dma_pool_free(struct dma_pool * pool,void * vaddr,dma_addr_t addr)48 static inline void dma_pool_free(struct dma_pool *pool, void *vaddr,
49 				 dma_addr_t addr) { }
dmam_pool_create(const char * name,struct device * dev,size_t size,size_t align,size_t allocation)50 static inline struct dma_pool *dmam_pool_create(const char *name,
51 	struct device *dev, size_t size, size_t align, size_t allocation)
52 { return NULL; }
dmam_pool_destroy(struct dma_pool * pool)53 static inline void dmam_pool_destroy(struct dma_pool *pool) { }
54 #endif /* !CONFIG_HAS_DMA */
55 
dma_pool_create(const char * name,struct device * dev,size_t size,size_t align,size_t boundary)56 static inline struct dma_pool *dma_pool_create(const char *name,
57 		struct device *dev, size_t size, size_t align, size_t boundary)
58 {
59 	return dma_pool_create_node(name, dev, size, align, boundary,
60 				    NUMA_NO_NODE);
61 }
62 
63 /**
64  * dma_pool_zalloc - Get a zero-initialized block of DMA coherent memory.
65  * @pool: dma pool that will produce the block
66  * @mem_flags: GFP_* bitmask
67  * @handle: pointer to dma address of block
68  *
69  * Same as dma_pool_alloc(), but the returned memory is zeroed.
70  */
dma_pool_zalloc(struct dma_pool * pool,gfp_t mem_flags,dma_addr_t * handle)71 static inline void *dma_pool_zalloc(struct dma_pool *pool, gfp_t mem_flags,
72 				    dma_addr_t *handle)
73 {
74 	return dma_pool_alloc(pool, mem_flags | __GFP_ZERO, handle);
75 }
76 
77 #endif
78 
79