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  * General memory allocation interfaces
  27  */
  28
  29 #define KM_SLEEP        0x0001u
  30 #define KM_NOSLEEP      0x0002u
  31 #define KM_NOFS         0x0004u
  32 #define KM_MAYFAIL      0x0008u
  33 #define KM_LARGE        0x0010u
  34
  35 /*
  36  * We use a special process flag to avoid recursive callbacks into
  37  * the filesystem during transactions.  We will also issue our own
  38  * warnings, so we explicitly skip any generic ones (silly of us).
  39  */
  40 static inline gfp_t
  41 kmem_flags_convert(unsigned int __nocast flags)
  42 {
  43         gfp_t   lflags;
  44
  45         BUG_ON(flags & ~(KM_SLEEP|KM_NOSLEEP|KM_NOFS|KM_MAYFAIL|KM_LARGE));
  46
  47         if (flags & KM_NOSLEEP) {
  48                 lflags = GFP_ATOMIC | __GFP_NOWARN;
  49         } else {
  50                 lflags = GFP_KERNEL | __GFP_NOWARN;
  51                 if ((current->flags & PF_FSTRANS) || (flags & KM_NOFS))
  52                         lflags &= ~__GFP_FS;
  53         }
  54         return lflags;
  55 }
  56
  57 extern void *kmem_alloc(size_t, unsigned int __nocast);
  58 extern void *kmem_zalloc(size_t, unsigned int __nocast);
  59 extern void *kmem_zalloc_greedy(size_t *, size_t, size_t, unsigned int __nocast);
  60 extern void *kmem_realloc(void *, size_t, size_t, unsigned int __nocast);
  61 extern void  kmem_free(void *, size_t);
  62
  63 /*
  64  * Zone interfaces
  65  */
  66
  67 #define KM_ZONE_HWALIGN SLAB_HWCACHE_ALIGN
  68 #define KM_ZONE_RECLAIM SLAB_RECLAIM_ACCOUNT
  69 #define KM_ZONE_SPREAD  SLAB_MEM_SPREAD
  70
  71 #define kmem_zone       kmem_cache
  72 #define kmem_zone_t     struct kmem_cache
  73
  74 static inline kmem_zone_t *
  75 kmem_zone_init(int size, char *zone_name)
  76 {
  77         return kmem_cache_create(zone_name, size, 0, 0, NULL, NULL);
  78 }
  79
  80 static inline kmem_zone_t *
  81 kmem_zone_init_flags(int size, char *zone_name, unsigned long flags,
  82                      void (*construct)(void *, kmem_zone_t *, unsigned long))
  83 {
  84         return kmem_cache_create(zone_name, size, 0, flags, construct, NULL);
  85 }
  86
  87 static inline void
  88 kmem_zone_free(kmem_zone_t *zone, void *ptr)
  89 {
  90         kmem_cache_free(zone, ptr);
  91 }
  92
  93 static inline void
  94 kmem_zone_destroy(kmem_zone_t *zone)
  95 {
  96         if (zone)
  97                 kmem_cache_destroy(zone);
  98 }
  99
 100 extern void *kmem_zone_alloc(kmem_zone_t *, unsigned int __nocast);
 101 extern void *kmem_zone_zalloc(kmem_zone_t *, unsigned int __nocast);
 102
 103 /*
 104  * Low memory cache shrinkers
 105  */
 106
 107 typedef struct shrinker *kmem_shaker_t;
 108 typedef int (*kmem_shake_func_t)(int, gfp_t);
 109
 110 static inline kmem_shaker_t
 111 kmem_shake_register(kmem_shake_func_t sfunc)
 112 {
 113         return set_shrinker(DEFAULT_SEEKS, sfunc);
 114 }
 115
 116 static inline void
 117 kmem_shake_deregister(kmem_shaker_t shrinker)
 118 {
 119         remove_shrinker(shrinker);
 120 }
 121
 122 static inline int
 123 kmem_shake_allow(gfp_t gfp_mask)
 124 {
 125         return (gfp_mask & __GFP_WAIT);
 126 }
 127
 128 #endif /* __XFS_SUPPORT_KMEM_H__ */