include/linux/mempool.h

   1 /*
   2  * memory buffer pool support
   3  */
   4 #ifndef _LINUX_MEMPOOL_H
   5 #define _LINUX_MEMPOOL_H
   6
   7 #include <linux/wait.h>
   8 #include <linux/compiler.h>
   9
  10 struct kmem_cache;
  11
  12 typedef void * (mempool_alloc_t)(gfp_t gfp_mask, void *pool_data);
  13 typedef void (mempool_free_t)(void *element, void *pool_data);
  14
  15 typedef struct mempool_s {
  16         spinlock_t lock;
  17         int min_nr;             /* nr of elements at *elements */
  18         int curr_nr;            /* Current nr of elements at *elements */
  19         void **elements;
  20
  21         void *pool_data;
  22         mempool_alloc_t *alloc;
  23         mempool_free_t *free;
  24         wait_queue_head_t wait;
  25 } mempool_t;
  26
  27 extern mempool_t *mempool_create(int min_nr, mempool_alloc_t *alloc_fn,
  28                         mempool_free_t *free_fn, void *pool_data);
  29 extern mempool_t *mempool_create_node(int min_nr, mempool_alloc_t *alloc_fn,
  30                         mempool_free_t *free_fn, void *pool_data,
  31                         gfp_t gfp_mask, int nid);
  32
  33 extern int mempool_resize(mempool_t *pool, int new_min_nr);
  34 extern void mempool_destroy(mempool_t *pool);
  35 extern void *mempool_alloc(mempool_t *pool, gfp_t gfp_mask) __malloc;
  36 extern void mempool_free(void *element, mempool_t *pool);
  37
  38 /*
  39  * A mempool_alloc_t and mempool_free_t that get the memory from
  40  * a slab cache that is passed in through pool_data.
  41  * Note: the slab cache may not have a ctor function.
  42  */
  43 void *mempool_alloc_slab(gfp_t gfp_mask, void *pool_data);
  44 void mempool_free_slab(void *element, void *pool_data);
  45 static inline mempool_t *
  46 mempool_create_slab_pool(int min_nr, struct kmem_cache *kc)
  47 {
  48         return mempool_create(min_nr, mempool_alloc_slab, mempool_free_slab,
  49                               (void *) kc);
  50 }
  51
  52 /*
  53  * a mempool_alloc_t and a mempool_free_t to kmalloc and kfree the
  54  * amount of memory specified by pool_data
  55  */
  56 void *mempool_kmalloc(gfp_t gfp_mask, void *pool_data);
  57 void mempool_kfree(void *element, void *pool_data);
  58 static inline mempool_t *mempool_create_kmalloc_pool(int min_nr, size_t size)
  59 {
  60         return mempool_create(min_nr, mempool_kmalloc, mempool_kfree,
  61                               (void *) size);
  62 }
  63
  64 /*
  65  * A mempool_alloc_t and mempool_free_t for a simple page allocator that
  66  * allocates pages of the order specified by pool_data
  67  */
  68 void *mempool_alloc_pages(gfp_t gfp_mask, void *pool_data);
  69 void mempool_free_pages(void *element, void *pool_data);
  70 static inline mempool_t *mempool_create_page_pool(int min_nr, int order)
  71 {
  72         return mempool_create(min_nr, mempool_alloc_pages, mempool_free_pages,
  73                               (void *)(long)order);
  74 }
  75
  76 #endif /* _LINUX_MEMPOOL_H */