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  * 2.6.39 API compat,
  54  * As for 2.6.39 invalidate_inodes() was updated to take a second
  55  * argument which controls how dirty inodes should be handled.
  56  */
  57 #ifdef HAVE_INVALIDATE_INODES
  58 # ifdef HAVE_2ARGS_INVALIDATE_INODES
  59 #  define spl_invalidate_inodes(sb, kd) invalidate_inodes(sb, kd)
  60 # else
  61 #  define spl_invalidate_inodes(sb, kd) invalidate_inodes(sb)
  62 # endif /* HAVE_2ARGS_INVALIDATE_INODES */
  63 #else
  64 # ifdef HAVE_2ARGS_INVALIDATE_INODES
  65 typedef int (*invalidate_inodes_t)(struct super_block *sb, bool kd);
  66 extern invalidate_inodes_t invalidate_inodes_fn;
  67 #  define spl_invalidate_inodes(sb, kd) invalidate_inodes_fn(sb, kd)
  68 # else
  69 typedef int (*invalidate_inodes_t)(struct super_block *sb);
  70 extern invalidate_inodes_t invalidate_inodes_fn;
  71 #  define spl_invalidate_inodes(sb, kd) invalidate_inodes_fn(sb)
  72 # endif /* HAVE_2ARGS_INVALIDATE_INODES */
  73 #endif /* HAVE_INVALIDATE_INODES */
  74
  75 /*
  76  * 2.6.xx API compat,
  77  * There currently exists no exposed API to partially shrink the dcache.
  78  * The expected mechanism to shrink the cache is a registered shrinker
  79  * which is called during memory pressure.
  80  */
  81 #ifndef HAVE_SHRINK_DCACHE_MEMORY
  82 # ifdef HAVE_3ARGS_SHRINKER_CALLBACK
  83 typedef int (*shrink_dcache_memory_t)(struct shrinker *, int, gfp_t);
  84 extern shrink_dcache_memory_t shrink_dcache_memory_fn;
  85 #  define shrink_dcache_memory(nr, gfp) shrink_dcache_memory_fn(NULL, nr, gfp)
  86 # else
  87 typedef int (*shrink_dcache_memory_t)(int, gfp_t);
  88 extern shrink_dcache_memory_t shrink_dcache_memory_fn;
  89 #  define shrink_dcache_memory(nr, gfp) shrink_dcache_memory_fn(nr, gfp)
  90 # endif /* HAVE_3ARGS_SHRINKER_CALLBACK */
  91 #endif /* HAVE_SHRINK_DCACHE_MEMORY */
  92
  93 /*
  94  * 2.6.xx API compat,
  95  * There currently exists no exposed API to partially shrink the icache.
  96  * The expected mechanism to shrink the cache is a registered shrinker
  97  * which is called during memory pressure.
  98  */
  99 #ifndef HAVE_SHRINK_ICACHE_MEMORY
 100 # ifdef HAVE_3ARGS_SHRINKER_CALLBACK
 101 typedef int (*shrink_icache_memory_t)(struct shrinker *, int, gfp_t);
 102 extern shrink_icache_memory_t shrink_icache_memory_fn;
 103 #  define shrink_icache_memory(nr, gfp) shrink_icache_memory_fn(NULL, nr, gfp)
 104 # else
 105 typedef int (*shrink_icache_memory_t)(int, gfp_t);
 106 extern shrink_icache_memory_t shrink_icache_memory_fn;
 107 #  define shrink_icache_memory(nr, gfp) shrink_icache_memory_fn(nr, gfp)
 108 # endif /* HAVE_3ARGS_SHRINKER_CALLBACK */
 109 #endif /* HAVE_SHRINK_ICACHE_MEMORY */
 110
 111 #ifdef HAVE_SET_SHRINKER
 112 typedef struct spl_shrinker {
 113         struct shrinker *shrinker;
 114         shrinker_t fn;
 115         int seeks;
 116 } spl_shrinker_t;
 117
 118 static inline void
 119 spl_register_shrinker(spl_shrinker_t *ss)
 120 {
 121         ss->shrinker = set_shrinker(ss->seeks, ss->fn);
 122 }
 123
 124 static inline void
 125 spl_unregister_shrinker(spl_shrinker_t *ss)
 126 {
 127         remove_shrinker(ss->shrinker);
 128 }
 129
 130 # define SPL_SHRINKER_DECLARE(s, x, y) \
 131         static spl_shrinker_t s = { .shrinker = NULL, .fn = x, .seeks = y }
 132 # define SPL_SHRINKER_CALLBACK_PROTO(fn, x, y, z) \
 133         static int fn(int y, unsigned int z)
 134 # define spl_exec_shrinker(ss, nr, gfp) \
 135         ((spl_shrinker_t *)ss)->fn(nr, gfp)
 136
 137 #else /* HAVE_SET_SHRINKER */
 138
 139 # define spl_register_shrinker(x)       register_shrinker(x)
 140 # define spl_unregister_shrinker(x)     unregister_shrinker(x)
 141 # define SPL_SHRINKER_DECLARE(s, x, y) \
 142         static struct shrinker s = { .shrink = x, .seeks = y }
 143
 144 # ifdef HAVE_3ARGS_SHRINKER_CALLBACK
 145 #  define SPL_SHRINKER_CALLBACK_PROTO(fn, x, y, z) \
 146         static int fn(struct shrinker *x, int y, unsigned int z)
 147 #  define spl_exec_shrinker(ss, nr, gfp) \
 148         ((struct shrinker *)ss)->shrink(NULL, nr, gfp)
 149 # else /* HAVE_3ARGS_SHRINKER_CALLBACK */
 150 #  define SPL_SHRINKER_CALLBACK_PROTO(fn, x, y, z) \
 151         static int fn(int y, unsigned int z)
 152 #  define spl_exec_shrinker(ss, nr, gfp) \
 153         ((struct shrinker *)ss)->shrink(nr, gfp)
 154 # endif /* HAVE_3ARGS_SHRINKER_CALLBACK */
 155 #endif /* HAVE_SET_SHRINKER */
 156
 157 #endif /* SPL_MM_COMPAT_H */