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
 13struct kmem_cache;
 14
 15typedef void * (mempool_alloc_t)(gfp_t gfp_mask, void *pool_data);
 16typedef void (mempool_free_t)(void *element, void *pool_data);
 17
 18typedef 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
 30static inline bool mempool_initialized(struct mempool *pool)
 31{
 32	return pool->elements != NULL;
 33}
 34
 35static inline bool mempool_is_saturated(struct mempool *pool)
 36{
 37	return READ_ONCE(pool->curr_nr) >= pool->min_nr;
 38}
 39
 40void mempool_exit(struct mempool *pool);
 41int 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);
 44int 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
 50struct mempool *mempool_create(int min_nr, mempool_alloc_t *alloc_fn,
 51		mempool_free_t *free_fn, void *pool_data);
 52struct 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
 62int mempool_resize(struct mempool *pool, int new_min_nr);
 63void mempool_destroy(struct mempool *pool);
 64
 65void *mempool_alloc_noprof(struct mempool *pool, gfp_t gfp_mask) __malloc;
 66#define mempool_alloc(...)						\
 67	alloc_hooks(mempool_alloc_noprof(__VA_ARGS__))
 68int 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
 73void *mempool_alloc_preallocated(struct mempool *pool) __malloc;
 74void mempool_free(void *element, struct mempool *pool);
 75unsigned 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 */
 83void *mempool_alloc_slab(gfp_t gfp_mask, void *pool_data);
 84void 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 */
 95void *mempool_kmalloc(gfp_t gfp_mask, void *pool_data);
 96void 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 */
109void *mempool_alloc_pages(gfp_t gfp_mask, void *pool_data);
110void 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 */