include/linux/mempool.h

   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_s {
  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
  30 static inline bool mempool_initialized(mempool_t *pool)
  31 {
  32         return pool->elements != NULL;
  33 }
  34
  35 static inline bool mempool_is_saturated(mempool_t *pool)
  36 {
  37         return READ_ONCE(pool->curr_nr) >= pool->min_nr;
  38 }
  39
  40 void mempool_exit(mempool_t *pool);
  41 int mempool_init_node(mempool_t *pool, int min_nr, mempool_alloc_t *alloc_fn,
  42                       mempool_free_t *free_fn, void *pool_data,
  43                       gfp_t gfp_mask, int node_id);
  44
  45 int mempool_init_noprof(mempool_t *pool, int min_nr, mempool_alloc_t *alloc_fn,
  46                  mempool_free_t *free_fn, void *pool_data);
  47 #define mempool_init(...)                                               \
  48         alloc_hooks(mempool_init_noprof(__VA_ARGS__))
  49
  50 extern mempool_t *mempool_create(int min_nr, mempool_alloc_t *alloc_fn,
  51                         mempool_free_t *free_fn, void *pool_data);
  52
  53 extern mempool_t *mempool_create_node_noprof(int min_nr, mempool_alloc_t *alloc_fn,
  54                         mempool_free_t *free_fn, void *pool_data,
  55                         gfp_t gfp_mask, int nid);
  56 #define mempool_create_node(...)                                        \
  57         alloc_hooks(mempool_create_node_noprof(__VA_ARGS__))
  58
  59 #define mempool_create(_min_nr, _alloc_fn, _free_fn, _pool_data)        \
  60         mempool_create_node(_min_nr, _alloc_fn, _free_fn, _pool_data,   \
  61                             GFP_KERNEL, NUMA_NO_NODE)
  62
  63 extern int mempool_resize(mempool_t *pool, int new_min_nr);
  64 extern void mempool_destroy(mempool_t *pool);
  65
  66 extern void *mempool_alloc_noprof(mempool_t *pool, gfp_t gfp_mask) __malloc;
  67 #define mempool_alloc(...)                                              \
  68         alloc_hooks(mempool_alloc_noprof(__VA_ARGS__))
  69
  70 extern void *mempool_alloc_preallocated(mempool_t *pool) __malloc;
  71 extern void mempool_free(void *element, mempool_t *pool);
  72
  73 /*
  74  * A mempool_alloc_t and mempool_free_t that get the memory from
  75  * a slab cache that is passed in through pool_data.
  76  * Note: the slab cache may not have a ctor function.
  77  */
  78 void *mempool_alloc_slab(gfp_t gfp_mask, void *pool_data);
  79 void mempool_free_slab(void *element, void *pool_data);
  80
  81 #define mempool_init_slab_pool(_pool, _min_nr, _kc)                     \
  82         mempool_init(_pool, (_min_nr), mempool_alloc_slab, mempool_free_slab, (void *)(_kc))
  83 #define mempool_create_slab_pool(_min_nr, _kc)                  \
  84         mempool_create((_min_nr), mempool_alloc_slab, mempool_free_slab, (void *)(_kc))
  85
  86 /*
  87  * a mempool_alloc_t and a mempool_free_t to kmalloc and kfree the
  88  * amount of memory specified by pool_data
  89  */
  90 void *mempool_kmalloc(gfp_t gfp_mask, void *pool_data);
  91 void mempool_kfree(void *element, void *pool_data);
  92
  93 #define mempool_init_kmalloc_pool(_pool, _min_nr, _size)                \
  94         mempool_init(_pool, (_min_nr), mempool_kmalloc, mempool_kfree,  \
  95                      (void *)(unsigned long)(_size))
  96 #define mempool_create_kmalloc_pool(_min_nr, _size)                     \
  97         mempool_create((_min_nr), mempool_kmalloc, mempool_kfree,       \
  98                        (void *)(unsigned long)(_size))
  99
 100 void *mempool_kvmalloc(gfp_t gfp_mask, void *pool_data);
 101 void mempool_kvfree(void *element, void *pool_data);
 102
 103 static inline int mempool_init_kvmalloc_pool(mempool_t *pool, int min_nr, size_t size)
 104 {
 105         return mempool_init(pool, min_nr, mempool_kvmalloc, mempool_kvfree, (void *) size);
 106 }
 107
 108 static inline mempool_t *mempool_create_kvmalloc_pool(int min_nr, size_t size)
 109 {
 110         return mempool_create(min_nr, mempool_kvmalloc, mempool_kvfree, (void *) size);
 111 }
 112
 113 /*
 114  * A mempool_alloc_t and mempool_free_t for a simple page allocator that
 115  * allocates pages of the order specified by pool_data
 116  */
 117 void *mempool_alloc_pages(gfp_t gfp_mask, void *pool_data);
 118 void mempool_free_pages(void *element, void *pool_data);
 119
 120 #define mempool_init_page_pool(_pool, _min_nr, _order)                  \
 121         mempool_init(_pool, (_min_nr), mempool_alloc_pages,             \
 122                      mempool_free_pages, (void *)(long)(_order))
 123 #define mempool_create_page_pool(_min_nr, _order)                       \
 124         mempool_create((_min_nr), mempool_alloc_pages,                  \
 125                        mempool_free_pages, (void *)(long)(_order))
 126
 127 #endif /* _LINUX_MEMPOOL_H */