include/linux/zsmalloc.h

   1 /*
   2  * zsmalloc memory allocator
   3  *
   4  * Copyright (C) 2011  Nitin Gupta
   5  * Copyright (C) 2012, 2013 Minchan Kim
   6  *
   7  * This code is released using a dual license strategy: BSD/GPL
   8  * You can choose the license that better fits your requirements.
   9  *
  10  * Released under the terms of 3-clause BSD License
  11  * Released under the terms of GNU General Public License Version 2.0
  12  */
  13
  14 #ifndef _ZS_MALLOC_H_
  15 #define _ZS_MALLOC_H_
  16
  17 #include <linux/types.h>
  18
  19 /*
  20  * zsmalloc mapping modes
  21  *
  22  * NOTE: These only make a difference when a mapped object spans pages.
  23  */
  24 enum zs_mapmode {
  25         ZS_MM_RW, /* normal read-write mapping */
  26         ZS_MM_RO, /* read-only (no copy-out at unmap time) */
  27         ZS_MM_WO /* write-only (no copy-in at map time) */
  28         /*
  29          * NOTE: ZS_MM_WO should only be used for initializing new
  30          * (uninitialized) allocations.  Partial writes to already
  31          * initialized allocations should use ZS_MM_RW to preserve the
  32          * existing data.
  33          */
  34 };
  35
  36 struct zs_pool_stats {
  37         /* How many pages were migrated (freed) */
  38         atomic_long_t pages_compacted;
  39 };
  40
  41 struct zs_pool;
  42
  43 struct zs_pool *zs_create_pool(const char *name);
  44 void zs_destroy_pool(struct zs_pool *pool);
  45
  46 unsigned long zs_malloc(struct zs_pool *pool, size_t size, gfp_t flags);
  47 void zs_free(struct zs_pool *pool, unsigned long obj);
  48
  49 size_t zs_huge_class_size(struct zs_pool *pool);
  50
  51 void *zs_map_object(struct zs_pool *pool, unsigned long handle,
  52                         enum zs_mapmode mm);
  53 void zs_unmap_object(struct zs_pool *pool, unsigned long handle);
  54
  55 unsigned long zs_get_total_pages(struct zs_pool *pool);
  56 unsigned long zs_compact(struct zs_pool *pool);
  57
  58 unsigned int zs_lookup_class_index(struct zs_pool *pool, unsigned int size);
  59
  60 void zs_pool_stats(struct zs_pool *pool, struct zs_pool_stats *stats);
  61 #endif