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);
70 #define mempool_alloc_bulk(...) \
71 alloc_hooks(mempool_alloc_bulk_noprof(__VA_ARGS__))
72
73 /*
74 * Allocate a new element without dipping into the pool's reserves or
75 * waiting. Returns NULL on failure.
76 */
77 #define mempool_alloc_noreserve(_pool, _gfp) \
78 alloc_hooks((_pool)->alloc(_gfp, (_pool)->pool_data))
79
80 void *mempool_alloc_preallocated(struct mempool *pool) __malloc;
81 void mempool_free(void *element, struct mempool *pool);
82 unsigned int mempool_free_bulk(struct mempool *pool, void **elem,
83 unsigned int count);
84
85 /*
86 * A mempool_alloc_t and mempool_free_t that get the memory from
87 * a slab cache that is passed in through pool_data.
88 * Note: the slab cache may not have a ctor function.
89 */
90 void *mempool_alloc_slab(gfp_t gfp_mask, void *pool_data);
91 void mempool_free_slab(void *element, void *pool_data);
92
93 #define mempool_init_slab_pool(_pool, _min_nr, _kc) \
94 mempool_init(_pool, (_min_nr), mempool_alloc_slab, mempool_free_slab, (void *)(_kc))
95 #define mempool_create_slab_pool(_min_nr, _kc) \
96 mempool_create((_min_nr), mempool_alloc_slab, mempool_free_slab, (void *)(_kc))
97
98 /*
99 * a mempool_alloc_t and a mempool_free_t to kmalloc and kfree the
100 * amount of memory specified by pool_data
101 */
102 void *mempool_kmalloc(gfp_t gfp_mask, void *pool_data);
103 void mempool_kfree(void *element, void *pool_data);
104
105 #define mempool_init_kmalloc_pool(_pool, _min_nr, _size) \
106 mempool_init(_pool, (_min_nr), mempool_kmalloc, mempool_kfree, \
107 (void *)(unsigned long)(_size))
108 #define mempool_create_kmalloc_pool(_min_nr, _size) \
109 mempool_create((_min_nr), mempool_kmalloc, mempool_kfree, \
110 (void *)(unsigned long)(_size))
111
112 /*
113 * A mempool_alloc_t and mempool_free_t for a simple page allocator that
114 * allocates pages of the order specified by pool_data
115 */
116 void *mempool_alloc_pages(gfp_t gfp_mask, void *pool_data);
117 void mempool_free_pages(void *element, void *pool_data);
118
119 #define mempool_init_page_pool(_pool, _min_nr, _order) \
120 mempool_init(_pool, (_min_nr), mempool_alloc_pages, \
121 mempool_free_pages, (void *)(long)(_order))
122 #define mempool_create_page_pool(_min_nr, _order) \
123 mempool_create((_min_nr), mempool_alloc_pages, \
124 mempool_free_pages, (void *)(long)(_order))
125
126 #endif /* _LINUX_MEMPOOL_H */
127