xref: /linux/include/linux/mempool.h (revision b687034b1a4d85333ced0fe07f67b17276cccdc8)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * memory buffer pool support
4  */
5 #ifndef _LINUX_MEMPOOL_H
6 #define _LINUX_MEMPOOL_H
7 
8 #include <linux/sched.h>
9 #include <linux/alloc_tag.h>
10 #include <linux/wait.h>
11 #include <linux/compiler.h>
12 
13 struct kmem_cache;
14 
15 typedef void * (mempool_alloc_t)(gfp_t gfp_mask, void *pool_data);
16 typedef void (mempool_free_t)(void *element, void *pool_data);
17 
18 typedef struct mempool {
19 	spinlock_t lock;
20 	int min_nr;		/* nr of elements at *elements */
21 	int curr_nr;		/* Current nr of elements at *elements */
22 	void **elements;
23 
24 	void *pool_data;
25 	mempool_alloc_t *alloc;
26 	mempool_free_t *free;
27 	wait_queue_head_t wait;
28 } mempool_t;
29 
mempool_initialized(struct mempool * pool)30 static inline bool mempool_initialized(struct mempool *pool)
31 {
32 	return pool->elements != NULL;
33 }
34 
mempool_is_saturated(struct mempool * pool)35 static inline bool mempool_is_saturated(struct mempool *pool)
36 {
37 	return READ_ONCE(pool->curr_nr) >= pool->min_nr;
38 }
39 
40 void mempool_exit(struct mempool *pool);
41 int mempool_init_node(struct mempool *pool, int min_nr,
42 		mempool_alloc_t *alloc_fn, mempool_free_t *free_fn,
43 		void *pool_data, gfp_t gfp_mask, int node_id);
44 int mempool_init_noprof(struct mempool *pool, int min_nr,
45 		mempool_alloc_t *alloc_fn, mempool_free_t *free_fn,
46 		void *pool_data);
47 #define mempool_init(...)						\
48 	alloc_hooks(mempool_init_noprof(__VA_ARGS__))
49 
50 struct mempool *mempool_create(int min_nr, mempool_alloc_t *alloc_fn,
51 		mempool_free_t *free_fn, void *pool_data);
52 struct mempool *mempool_create_node_noprof(int min_nr,
53 		mempool_alloc_t *alloc_fn, mempool_free_t *free_fn,
54 		void *pool_data, gfp_t gfp_mask, int nid);
55 #define mempool_create_node(...)					\
56 	alloc_hooks(mempool_create_node_noprof(__VA_ARGS__))
57 
58 #define mempool_create(_min_nr, _alloc_fn, _free_fn, _pool_data)	\
59 	mempool_create_node(_min_nr, _alloc_fn, _free_fn, _pool_data,	\
60 			    GFP_KERNEL, NUMA_NO_NODE)
61 
62 int mempool_resize(struct mempool *pool, int new_min_nr);
63 void mempool_destroy(struct mempool *pool);
64 
65 void *mempool_alloc_noprof(struct mempool *pool, gfp_t gfp_mask) __malloc;
66 #define mempool_alloc(...)						\
67 	alloc_hooks(mempool_alloc_noprof(__VA_ARGS__))
68 int mempool_alloc_bulk_noprof(struct mempool *pool, void **elem,
69 		unsigned int count, unsigned int allocated);
70 #define mempool_alloc_bulk(...)						\
71 	alloc_hooks(mempool_alloc_bulk_noprof(__VA_ARGS__))
72 
73 void *mempool_alloc_preallocated(struct mempool *pool) __malloc;
74 void mempool_free(void *element, struct mempool *pool);
75 unsigned int mempool_free_bulk(struct mempool *pool, void **elem,
76 		unsigned int count);
77 
78 /*
79  * A mempool_alloc_t and mempool_free_t that get the memory from
80  * a slab cache that is passed in through pool_data.
81  * Note: the slab cache may not have a ctor function.
82  */
83 void *mempool_alloc_slab(gfp_t gfp_mask, void *pool_data);
84 void mempool_free_slab(void *element, void *pool_data);
85 
86 #define mempool_init_slab_pool(_pool, _min_nr, _kc)			\
87 	mempool_init(_pool, (_min_nr), mempool_alloc_slab, mempool_free_slab, (void *)(_kc))
88 #define mempool_create_slab_pool(_min_nr, _kc)			\
89 	mempool_create((_min_nr), mempool_alloc_slab, mempool_free_slab, (void *)(_kc))
90 
91 /*
92  * a mempool_alloc_t and a mempool_free_t to kmalloc and kfree the
93  * amount of memory specified by pool_data
94  */
95 void *mempool_kmalloc(gfp_t gfp_mask, void *pool_data);
96 void mempool_kfree(void *element, void *pool_data);
97 
98 #define mempool_init_kmalloc_pool(_pool, _min_nr, _size)		\
99 	mempool_init(_pool, (_min_nr), mempool_kmalloc, mempool_kfree,	\
100 		     (void *)(unsigned long)(_size))
101 #define mempool_create_kmalloc_pool(_min_nr, _size)			\
102 	mempool_create((_min_nr), mempool_kmalloc, mempool_kfree,	\
103 		       (void *)(unsigned long)(_size))
104 
105 /*
106  * A mempool_alloc_t and mempool_free_t for a simple page allocator that
107  * allocates pages of the order specified by pool_data
108  */
109 void *mempool_alloc_pages(gfp_t gfp_mask, void *pool_data);
110 void mempool_free_pages(void *element, void *pool_data);
111 
112 #define mempool_init_page_pool(_pool, _min_nr, _order)			\
113 	mempool_init(_pool, (_min_nr), mempool_alloc_pages,		\
114 		     mempool_free_pages, (void *)(long)(_order))
115 #define mempool_create_page_pool(_min_nr, _order)			\
116 	mempool_create((_min_nr), mempool_alloc_pages,			\
117 		       mempool_free_pages, (void *)(long)(_order))
118 
119 #endif /* _LINUX_MEMPOOL_H */
120