include/linux/genalloc.h

   1 /*
   2  * Basic general purpose allocator for managing special purpose memory
   3  * not managed by the regular kmalloc/kfree interface.
   4  * Uses for this includes on-device special memory, uncached memory
   5  * etc.
   6  *
   7  * This code is based on the buddy allocator found in the sym53c8xx_2
   8  * driver, adapted for general purpose use.
   9  *
  10  * This source code is licensed under the GNU General Public License,
  11  * Version 2.  See the file COPYING for more details.
  12  */
  13
  14 #include <linux/spinlock.h>
  15
  16 #define ALLOC_MIN_SHIFT         5 /* 32 bytes minimum */
  17 /*
  18  *  Link between free memory chunks of a given size.
  19  */
  20 struct gen_pool_link {
  21         struct gen_pool_link *next;
  22 };
  23
  24 /*
  25  *  Memory pool descriptor.
  26  */
  27 struct gen_pool {
  28         spinlock_t lock;
  29         unsigned long (*get_new_chunk)(struct gen_pool *);
  30         struct gen_pool *next;
  31         struct gen_pool_link *h;
  32         unsigned long private;
  33         int max_chunk_shift;
  34 };
  35
  36 unsigned long gen_pool_alloc(struct gen_pool *poolp, int size);
  37 void gen_pool_free(struct gen_pool *mp, unsigned long ptr, int size);
  38 struct gen_pool *gen_pool_create(int nr_chunks, int max_chunk_shift,
  39                                  unsigned long (*fp)(struct gen_pool *),
  40                                  unsigned long data);