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/wait.h> 9 #include <linux/compiler.h> 10 11 struct kmem_cache; 12 13 typedef void * (mempool_alloc_t)(gfp_t gfp_mask, void *pool_data); 14 typedef void (mempool_free_t)(void *element, void *pool_data); 15 16 typedef struct mempool_s { 17 spinlock_t lock; 18 int min_nr; /* nr of elements at *elements */ 19 int curr_nr; /* Current nr of elements at *elements */ 20 void **elements; 21 22 void *pool_data; 23 mempool_alloc_t *alloc; 24 mempool_free_t *free; 25 wait_queue_head_t wait; 26 } mempool_t; 27 28 static inline bool mempool_initialized(mempool_t *pool) 29 { 30 return pool->elements != NULL; 31 } 32 33 static inline bool mempool_is_saturated(mempool_t *pool) 34 { 35 return READ_ONCE(pool->curr_nr) >= pool->min_nr; 36 } 37 38 void mempool_exit(mempool_t *pool); 39 int mempool_init_node(mempool_t *pool, int min_nr, mempool_alloc_t *alloc_fn, 40 mempool_free_t *free_fn, void *pool_data, 41 gfp_t gfp_mask, int node_id); 42 int mempool_init(mempool_t *pool, int min_nr, mempool_alloc_t *alloc_fn, 43 mempool_free_t *free_fn, void *pool_data); 44 45 extern mempool_t *mempool_create(int min_nr, mempool_alloc_t *alloc_fn, 46 mempool_free_t *free_fn, void *pool_data); 47 extern mempool_t *mempool_create_node(int min_nr, mempool_alloc_t *alloc_fn, 48 mempool_free_t *free_fn, void *pool_data, 49 gfp_t gfp_mask, int nid); 50 51 extern int mempool_resize(mempool_t *pool, int new_min_nr); 52 extern void mempool_destroy(mempool_t *pool); 53 extern void *mempool_alloc(mempool_t *pool, gfp_t gfp_mask) __malloc; 54 extern void *mempool_alloc_preallocated(mempool_t *pool) __malloc; 55 extern void mempool_free(void *element, mempool_t *pool); 56 57 /* 58 * A mempool_alloc_t and mempool_free_t that get the memory from 59 * a slab cache that is passed in through pool_data. 60 * Note: the slab cache may not have a ctor function. 61 */ 62 void *mempool_alloc_slab(gfp_t gfp_mask, void *pool_data); 63 void mempool_free_slab(void *element, void *pool_data); 64 65 static inline int 66 mempool_init_slab_pool(mempool_t *pool, int min_nr, struct kmem_cache *kc) 67 { 68 return mempool_init(pool, min_nr, mempool_alloc_slab, 69 mempool_free_slab, (void *) kc); 70 } 71 72 static inline mempool_t * 73 mempool_create_slab_pool(int min_nr, struct kmem_cache *kc) 74 { 75 return mempool_create(min_nr, mempool_alloc_slab, mempool_free_slab, 76 (void *) kc); 77 } 78 79 /* 80 * a mempool_alloc_t and a mempool_free_t to kmalloc and kfree the 81 * amount of memory specified by pool_data 82 */ 83 void *mempool_kmalloc(gfp_t gfp_mask, void *pool_data); 84 void mempool_kfree(void *element, void *pool_data); 85 86 static inline int mempool_init_kmalloc_pool(mempool_t *pool, int min_nr, size_t size) 87 { 88 return mempool_init(pool, min_nr, mempool_kmalloc, 89 mempool_kfree, (void *) size); 90 } 91 92 static inline mempool_t *mempool_create_kmalloc_pool(int min_nr, size_t size) 93 { 94 return mempool_create(min_nr, mempool_kmalloc, mempool_kfree, 95 (void *) size); 96 } 97 98 void *mempool_kvmalloc(gfp_t gfp_mask, void *pool_data); 99 void mempool_kvfree(void *element, void *pool_data); 100 101 static inline int mempool_init_kvmalloc_pool(mempool_t *pool, int min_nr, size_t size) 102 { 103 return mempool_init(pool, min_nr, mempool_kvmalloc, mempool_kvfree, (void *) size); 104 } 105 106 static inline mempool_t *mempool_create_kvmalloc_pool(int min_nr, size_t size) 107 { 108 return mempool_create(min_nr, mempool_kvmalloc, mempool_kvfree, (void *) size); 109 } 110 111 /* 112 * A mempool_alloc_t and mempool_free_t for a simple page allocator that 113 * allocates pages of the order specified by pool_data 114 */ 115 void *mempool_alloc_pages(gfp_t gfp_mask, void *pool_data); 116 void mempool_free_pages(void *element, void *pool_data); 117 118 static inline int mempool_init_page_pool(mempool_t *pool, int min_nr, int order) 119 { 120 return mempool_init(pool, min_nr, mempool_alloc_pages, 121 mempool_free_pages, (void *)(long)order); 122 } 123 124 static inline mempool_t *mempool_create_page_pool(int min_nr, int order) 125 { 126 return mempool_create(min_nr, mempool_alloc_pages, mempool_free_pages, 127 (void *)(long)order); 128 } 129 130 #endif /* _LINUX_MEMPOOL_H */ 131