include/linux/mm_compat.h

   1 /*****************************************************************************\
   2  *  Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
   3  *  Copyright (C) 2007 The Regents of the University of California.
   4  *  Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
   5  *  Written by Brian Behlendorf <behlendorf1@llnl.gov>.
   6  *  UCRL-CODE-235197
   7  *
   8  *  This file is part of the SPL, Solaris Porting Layer.
   9  *  For details, see <http://github.com/behlendorf/spl/>.
  10  *
  11  *  The SPL is free software; you can redistribute it and/or modify it
  12  *  under the terms of the GNU General Public License as published by the
  13  *  Free Software Foundation; either version 2 of the License, or (at your
  14  *  option) any later version.
  15  *
  16  *  The SPL is distributed in the hope that it will be useful, but WITHOUT
  17  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  18  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  19  *  for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License along
  22  *  with the SPL.  If not, see <http://www.gnu.org/licenses/>.
  23 \*****************************************************************************/
  24
  25 #ifndef _SPL_MM_COMPAT_H
  26 #define _SPL_MM_COMPAT_H
  27
  28 #include <linux/mm.h>
  29 #include <linux/fs.h>
  30
  31 /*
  32  * Linux 2.6.31 API Change.
  33  * Individual pages_{min,low,high} moved in to watermark array.
  34  */
  35 #ifndef min_wmark_pages
  36 #define min_wmark_pages(z)      (z->pages_min)
  37 #endif
  38
  39 #ifndef low_wmark_pages
  40 #define low_wmark_pages(z)      (z->pages_low)
  41 #endif
  42
  43 #ifndef high_wmark_pages
  44 #define high_wmark_pages(z)     (z->pages_high)
  45 #endif
  46
  47 /*
  48  * 2.6.37 API compat,
  49  * The function invalidate_inodes() is no longer exported by the kernel.
  50  * The prototype however is still available which means it is safe
  51  * to acquire the symbol's address using spl_kallsyms_lookup_name().
  52  */
  53 #ifndef HAVE_INVALIDATE_INODES
  54 typedef int (*invalidate_inodes_t)(struct super_block *sb);
  55 extern invalidate_inodes_t invalidate_inodes_fn;
  56 #define invalidate_inodes(sb)   invalidate_inodes_fn(sb)
  57 #endif /* HAVE_INVALIDATE_INODES */
  58
  59 /*
  60  * 2.6.xx API compat,
  61  * There currently exists no exposed API to partially shrink the dcache.
  62  * The expected mechanism to shrink the cache is a registered shrinker
  63  * which is called during memory pressure.
  64  */
  65 #ifndef HAVE_SHRINK_DCACHE_MEMORY
  66 # ifdef HAVE_3ARGS_SHRINKER_CALLBACK
  67 typedef int (*shrink_dcache_memory_t)(struct shrinker *, int, gfp_t);
  68 extern shrink_dcache_memory_t shrink_dcache_memory_fn;
  69 #  define shrink_dcache_memory(nr, gfp) shrink_dcache_memory_fn(NULL, nr, gfp)
  70 # else
  71 typedef int (*shrink_dcache_memory_t)(int, gfp_t);
  72 extern shrink_dcache_memory_t shrink_dcache_memory_fn;
  73 #  define shrink_dcache_memory(nr, gfp) shrink_dcache_memory_fn(nr, gfp)
  74 # endif /* HAVE_3ARGS_SHRINKER_CALLBACK */
  75 #endif /* HAVE_SHRINK_DCACHE_MEMORY */
  76
  77 /*
  78  * 2.6.xx API compat,
  79  * There currently exists no exposed API to partially shrink the icache.
  80  * The expected mechanism to shrink the cache is a registered shrinker
  81  * which is called during memory pressure.
  82  */
  83 #ifndef HAVE_SHRINK_ICACHE_MEMORY
  84 # ifdef HAVE_3ARGS_SHRINKER_CALLBACK
  85 typedef int (*shrink_icache_memory_t)(struct shrinker *, int, gfp_t);
  86 extern shrink_icache_memory_t shrink_icache_memory_fn;
  87 #  define shrink_icache_memory(nr, gfp) shrink_icache_memory_fn(NULL, nr, gfp)
  88 # else
  89 typedef int (*shrink_icache_memory_t)(int, gfp_t);
  90 extern shrink_icache_memory_t shrink_icache_memory_fn;
  91 #  define shrink_icache_memory(nr, gfp) shrink_icache_memory_fn(nr, gfp)
  92 # endif /* HAVE_3ARGS_SHRINKER_CALLBACK */
  93 #endif /* HAVE_SHRINK_ICACHE_MEMORY */
  94
  95 #ifdef HAVE_SET_SHRINKER
  96 typedef struct spl_shrinker {
  97         struct shrinker *shrinker;
  98         shrinker_t fn;
  99         int seeks;
 100 } spl_shrinker_t;
 101
 102 static inline void
 103 spl_register_shrinker(spl_shrinker_t *ss)
 104 {
 105         ss->shrinker = set_shrinker(ss->seeks, ss->fn);
 106 }
 107
 108 static inline void
 109 spl_unregister_shrinker(spl_shrinker_t *ss)
 110 {
 111         remove_shrinker(ss->shrinker);
 112 }
 113
 114 # define SPL_SHRINKER_DECLARE(s, x, y) \
 115         static spl_shrinker_t s = { .shrinker = NULL, .fn = x, .seeks = y }
 116 # define SPL_SHRINKER_CALLBACK_PROTO(fn, x, y, z) \
 117         static int fn(int y, unsigned int z)
 118 # define spl_exec_shrinker(ss, nr, gfp) \
 119         ((spl_shrinker_t *)ss)->fn(nr, gfp)
 120
 121 #else /* HAVE_SET_SHRINKER */
 122
 123 # define spl_register_shrinker(x)       register_shrinker(x)
 124 # define spl_unregister_shrinker(x)     unregister_shrinker(x)
 125 # define SPL_SHRINKER_DECLARE(s, x, y) \
 126         static struct shrinker s = { .shrink = x, .seeks = y }
 127
 128 # ifdef HAVE_3ARGS_SHRINKER_CALLBACK
 129 #  define SPL_SHRINKER_CALLBACK_PROTO(fn, x, y, z) \
 130         static int fn(struct shrinker *x, int y, unsigned int z)
 131 #  define spl_exec_shrinker(ss, nr, gfp) \
 132         ((struct shrinker *)ss)->shrink(NULL, nr, gfp)
 133 # else /* HAVE_3ARGS_SHRINKER_CALLBACK */
 134 #  define SPL_SHRINKER_CALLBACK_PROTO(fn, x, y, z) \
 135         static int fn(int y, unsigned int z)
 136 #  define spl_exec_shrinker(ss, nr, gfp) \
 137         ((struct shrinker *)ss)->shrink(nr, gfp)
 138 # endif /* HAVE_3ARGS_SHRINKER_CALLBACK */
 139 #endif /* HAVE_SET_SHRINKER */
 140
 141 #endif /* SPL_MM_COMPAT_H */