1/*
2 * memory buffer pool support
3 */
4#ifndef _LINUX_MEMPOOL_H
5#define _LINUX_MEMPOOL_H
6
7#include <linux/wait.h>
8
9struct kmem_cache;
10
11typedef void * (mempool_alloc_t)(gfp_t gfp_mask, void *pool_data);
12typedef void (mempool_free_t)(void *element, void *pool_data);
13
14typedef struct mempool_s {
15	spinlock_t lock;
16	int min_nr;		/* nr of elements at *elements */
17	int curr_nr;		/* Current nr of elements at *elements */
18	void **elements;
19
20	void *pool_data;
21	mempool_alloc_t *alloc;
22	mempool_free_t *free;
23	wait_queue_head_t wait;
24} mempool_t;
25
26extern mempool_t *mempool_create(int min_nr, mempool_alloc_t *alloc_fn,
27			mempool_free_t *free_fn, void *pool_data);
28extern mempool_t *mempool_create_node(int min_nr, mempool_alloc_t *alloc_fn,
29			mempool_free_t *free_fn, void *pool_data,
30			gfp_t gfp_mask, int nid);
31
32extern int mempool_resize(mempool_t *pool, int new_min_nr);
33extern void mempool_destroy(mempool_t *pool);
34extern void * mempool_alloc(mempool_t *pool, gfp_t gfp_mask);
35extern void mempool_free(void *element, mempool_t *pool);
36
37/*
38 * A mempool_alloc_t and mempool_free_t that get the memory from
39 * a slab cache that is passed in through pool_data.
40 * Note: the slab cache may not have a ctor function.
41 */
42void *mempool_alloc_slab(gfp_t gfp_mask, void *pool_data);
43void mempool_free_slab(void *element, void *pool_data);
44static inline mempool_t *
45mempool_create_slab_pool(int min_nr, struct kmem_cache *kc)
46{
47	return mempool_create(min_nr, mempool_alloc_slab, mempool_free_slab,
48			      (void *) kc);
49}
50
51/*
52 * a mempool_alloc_t and a mempool_free_t to kmalloc and kfree the
53 * amount of memory specified by pool_data
54 */
55void *mempool_kmalloc(gfp_t gfp_mask, void *pool_data);
56void mempool_kfree(void *element, void *pool_data);
57static inline mempool_t *mempool_create_kmalloc_pool(int min_nr, size_t size)
58{
59	return mempool_create(min_nr, mempool_kmalloc, mempool_kfree,
60			      (void *) size);
61}
62
63/*
64 * A mempool_alloc_t and mempool_free_t for a simple page allocator that
65 * allocates pages of the order specified by pool_data
66 */
67void *mempool_alloc_pages(gfp_t gfp_mask, void *pool_data);
68void mempool_free_pages(void *element, void *pool_data);
69static inline mempool_t *mempool_create_page_pool(int min_nr, int order)
70{
71	return mempool_create(min_nr, mempool_alloc_pages, mempool_free_pages,
72			      (void *)(long)order);
73}
74
75#endif /* _LINUX_MEMPOOL_H */
76