fs/xfs/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 #include <linux/vmalloc.h>
  25
  26 /*
  27  * General memory allocation interfaces
  28  */
  29
  30 typedef unsigned __bitwise xfs_km_flags_t;
  31 #define KM_SLEEP        ((__force xfs_km_flags_t)0x0001u)
  32 #define KM_NOSLEEP      ((__force xfs_km_flags_t)0x0002u)
  33 #define KM_NOFS         ((__force xfs_km_flags_t)0x0004u)
  34 #define KM_MAYFAIL      ((__force xfs_km_flags_t)0x0008u)
  35 #define KM_ZERO         ((__force xfs_km_flags_t)0x0010u)
  36
  37 /*
  38  * We use a special process flag to avoid recursive callbacks into
  39  * the filesystem during transactions.  We will also issue our own
  40  * warnings, so we explicitly skip any generic ones (silly of us).
  41  */
  42 static inline gfp_t
  43 kmem_flags_convert(xfs_km_flags_t flags)
  44 {
  45         gfp_t   lflags;
  46
  47         BUG_ON(flags & ~(KM_SLEEP|KM_NOSLEEP|KM_NOFS|KM_MAYFAIL|KM_ZERO));
  48
  49         if (flags & KM_NOSLEEP) {
  50                 lflags = GFP_ATOMIC | __GFP_NOWARN;
  51         } else {
  52                 lflags = GFP_KERNEL | __GFP_NOWARN;
  53                 if (flags & KM_NOFS)
  54                         lflags &= ~__GFP_FS;
  55         }
  56
  57         /*
  58          * Default page/slab allocator behavior is to retry for ever
  59          * for small allocations. We can override this behavior by using
  60          * __GFP_RETRY_MAYFAIL which will tell the allocator to retry as long
  61          * as it is feasible but rather fail than retry forever for all
  62          * request sizes.
  63          */
  64         if (flags & KM_MAYFAIL)
  65                 lflags |= __GFP_RETRY_MAYFAIL;
  66
  67         if (flags & KM_ZERO)
  68                 lflags |= __GFP_ZERO;
  69
  70         return lflags;
  71 }
  72
  73 extern void *kmem_alloc(size_t, xfs_km_flags_t);
  74 extern void *kmem_zalloc_large(size_t size, xfs_km_flags_t);
  75 extern void *kmem_realloc(const void *, size_t, xfs_km_flags_t);
  76 static inline void  kmem_free(const void *ptr)
  77 {
  78         kvfree(ptr);
  79 }
  80
  81
  82 static inline void *
  83 kmem_zalloc(size_t size, xfs_km_flags_t flags)
  84 {
  85         return kmem_alloc(size, flags | KM_ZERO);
  86 }
  87
  88 /*
  89  * Zone interfaces
  90  */
  91
  92 #define KM_ZONE_HWALIGN SLAB_HWCACHE_ALIGN
  93 #define KM_ZONE_RECLAIM SLAB_RECLAIM_ACCOUNT
  94 #define KM_ZONE_SPREAD  SLAB_MEM_SPREAD
  95 #define KM_ZONE_ACCOUNT SLAB_ACCOUNT
  96
  97 #define kmem_zone       kmem_cache
  98 #define kmem_zone_t     struct kmem_cache
  99
 100 static inline kmem_zone_t *
 101 kmem_zone_init(int size, char *zone_name)
 102 {
 103         return kmem_cache_create(zone_name, size, 0, 0, NULL);
 104 }
 105
 106 static inline kmem_zone_t *
 107 kmem_zone_init_flags(int size, char *zone_name, unsigned long flags,
 108                      void (*construct)(void *))
 109 {
 110         return kmem_cache_create(zone_name, size, 0, flags, construct);
 111 }
 112
 113 static inline void
 114 kmem_zone_free(kmem_zone_t *zone, void *ptr)
 115 {
 116         kmem_cache_free(zone, ptr);
 117 }
 118
 119 static inline void
 120 kmem_zone_destroy(kmem_zone_t *zone)
 121 {
 122         if (zone)
 123                 kmem_cache_destroy(zone);
 124 }
 125
 126 extern void *kmem_zone_alloc(kmem_zone_t *, xfs_km_flags_t);
 127
 128 static inline void *
 129 kmem_zone_zalloc(kmem_zone_t *zone, xfs_km_flags_t flags)
 130 {
 131         return kmem_zone_alloc(zone, flags | KM_ZERO);
 132 }
 133
 134 #endif /* __XFS_SUPPORT_KMEM_H__ */