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