fs/xfs/linux-2.6/kmem.h

   1 /*
   2  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   3  * All Rights Reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it would be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write the Free Software Foundation,
  16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18 #ifndef __XFS_SUPPORT_KMEM_H__
  19 #define __XFS_SUPPORT_KMEM_H__
  20
  21 #include <linux/slab.h>
  22 #include <linux/sched.h>
  23 #include <linux/mm.h>
  24
  25 /*
  26  * memory management routines
  27  */
  28 #define KM_SLEEP        0x0001u
  29 #define KM_NOSLEEP      0x0002u
  30 #define KM_NOFS         0x0004u
  31 #define KM_MAYFAIL      0x0008u
  32
  33 #define kmem_zone       kmem_cache
  34 #define kmem_zone_t     struct kmem_cache
  35
  36 typedef unsigned long xfs_pflags_t;
  37
  38 #define PFLAGS_TEST_NOIO()              (current->flags & PF_NOIO)
  39 #define PFLAGS_TEST_FSTRANS()           (current->flags & PF_FSTRANS)
  40
  41 #define PFLAGS_SET_NOIO() do {          \
  42         current->flags |= PF_NOIO;      \
  43 } while (0)
  44
  45 #define PFLAGS_CLEAR_NOIO() do {        \
  46         current->flags &= ~PF_NOIO;     \
  47 } while (0)
  48
  49 /* these could be nested, so we save state */
  50 #define PFLAGS_SET_FSTRANS(STATEP) do { \
  51         *(STATEP) = current->flags;     \
  52         current->flags |= PF_FSTRANS;   \
  53 } while (0)
  54
  55 #define PFLAGS_CLEAR_FSTRANS(STATEP) do { \
  56         *(STATEP) = current->flags;     \
  57         current->flags &= ~PF_FSTRANS;  \
  58 } while (0)
  59
  60 /* Restore the PF_FSTRANS state to what was saved in STATEP */
  61 #define PFLAGS_RESTORE_FSTRANS(STATEP) do {                     \
  62         current->flags = ((current->flags & ~PF_FSTRANS) |      \
  63                           (*(STATEP) & PF_FSTRANS));            \
  64 } while (0)
  65
  66 #define PFLAGS_DUP(OSTATEP, NSTATEP) do { \
  67         *(NSTATEP) = *(OSTATEP);        \
  68 } while (0)
  69
  70 static __inline gfp_t kmem_flags_convert(unsigned int __nocast flags)
  71 {
  72         gfp_t   lflags = __GFP_NOWARN;  /* we'll report problems, if need be */
  73
  74 #ifdef DEBUG
  75         if (unlikely(flags & ~(KM_SLEEP|KM_NOSLEEP|KM_NOFS|KM_MAYFAIL))) {
  76                 printk(KERN_WARNING
  77                     "XFS: memory allocation with wrong flags (%x)\n", flags);
  78                 BUG();
  79         }
  80 #endif
  81
  82         if (flags & KM_NOSLEEP) {
  83                 lflags |= GFP_ATOMIC;
  84         } else {
  85                 lflags |= GFP_KERNEL;
  86
  87                 /* avoid recusive callbacks to filesystem during transactions */
  88                 if (PFLAGS_TEST_FSTRANS() || (flags & KM_NOFS))
  89                         lflags &= ~__GFP_FS;
  90         }
  91
  92         return lflags;
  93 }
  94
  95 static __inline kmem_zone_t *
  96 kmem_zone_init(int size, char *zone_name)
  97 {
  98         return kmem_cache_create(zone_name, size, 0, 0, NULL, NULL);
  99 }
 100
 101 static __inline void
 102 kmem_zone_free(kmem_zone_t *zone, void *ptr)
 103 {
 104         kmem_cache_free(zone, ptr);
 105 }
 106
 107 static __inline void
 108 kmem_zone_destroy(kmem_zone_t *zone)
 109 {
 110         if (zone && kmem_cache_destroy(zone))
 111                 BUG();
 112 }
 113
 114 extern void *kmem_zone_zalloc(kmem_zone_t *, unsigned int __nocast);
 115 extern void *kmem_zone_alloc(kmem_zone_t *, unsigned int __nocast);
 116
 117 extern void *kmem_alloc(size_t, unsigned int __nocast);
 118 extern void *kmem_realloc(void *, size_t, size_t, unsigned int __nocast);
 119 extern void *kmem_zalloc(size_t, unsigned int __nocast);
 120 extern void  kmem_free(void *, size_t);
 121
 122 typedef struct shrinker *kmem_shaker_t;
 123 typedef int (*kmem_shake_func_t)(int, gfp_t);
 124
 125 static __inline kmem_shaker_t
 126 kmem_shake_register(kmem_shake_func_t sfunc)
 127 {
 128         return set_shrinker(DEFAULT_SEEKS, sfunc);
 129 }
 130
 131 static __inline void
 132 kmem_shake_deregister(kmem_shaker_t shrinker)
 133 {
 134         remove_shrinker(shrinker);
 135 }
 136
 137 static __inline int
 138 kmem_shake_allow(gfp_t gfp_mask)
 139 {
 140         return (gfp_mask & __GFP_WAIT);
 141 }
 142
 143 #endif /* __XFS_SUPPORT_KMEM_H__ */