release/src-rt-6.x.4708/linux/linux-2.6.36/fs/xfs/linux-2.6/kmem.c

   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 #include <linux/mm.h>
  19 #include <linux/highmem.h>
  20 #include <linux/slab.h>
  21 #include <linux/swap.h>
  22 #include <linux/blkdev.h>
  23 #include <linux/backing-dev.h>
  24 #include "time.h"
  25 #include "kmem.h"
  26
  27 /*
  28  * Greedy allocation.  May fail and may return vmalloced memory.
  29  *
  30  * Must be freed using kmem_free_large.
  31  */
  32 void *
  33 kmem_zalloc_greedy(size_t *size, size_t minsize, size_t maxsize)
  34 {
  35         void            *ptr;
  36         size_t          kmsize = maxsize;
  37
  38         while (!(ptr = kmem_zalloc_large(kmsize))) {
  39                 if ((kmsize >>= 1) <= minsize)
  40                         kmsize = minsize;
  41         }
  42         if (ptr)
  43                 *size = kmsize;
  44         return ptr;
  45 }
  46
  47 void *
  48 kmem_alloc(size_t size, unsigned int __nocast flags)
  49 {
  50         int     retries = 0;
  51         gfp_t   lflags = kmem_flags_convert(flags);
  52         void    *ptr;
  53
  54         do {
  55                 ptr = kmalloc(size, lflags);
  56                 if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP)))
  57                         return ptr;
  58                 if (!(++retries % 100))
  59                         printk(KERN_ERR "XFS: possible memory allocation "
  60                                         "deadlock in %s (mode:0x%x)\n",
  61                                         __func__, lflags);
  62                 congestion_wait(BLK_RW_ASYNC, HZ/50);
  63         } while (1);
  64 }
  65
  66 void *
  67 kmem_zalloc(size_t size, unsigned int __nocast flags)
  68 {
  69         void    *ptr;
  70
  71         ptr = kmem_alloc(size, flags);
  72         if (ptr)
  73                 memset((char *)ptr, 0, (int)size);
  74         return ptr;
  75 }
  76
  77 void
  78 kmem_free(const void *ptr)
  79 {
  80         if (!is_vmalloc_addr(ptr)) {
  81                 kfree(ptr);
  82         } else {
  83                 vfree(ptr);
  84         }
  85 }
  86
  87 void *
  88 kmem_realloc(const void *ptr, size_t newsize, size_t oldsize,
  89              unsigned int __nocast flags)
  90 {
  91         void    *new;
  92
  93         new = kmem_alloc(newsize, flags);
  94         if (ptr) {
  95                 if (new)
  96                         memcpy(new, ptr,
  97                                 ((oldsize < newsize) ? oldsize : newsize));
  98                 kmem_free(ptr);
  99         }
 100         return new;
 101 }
 102
 103 void *
 104 kmem_zone_alloc(kmem_zone_t *zone, unsigned int __nocast flags)
 105 {
 106         int     retries = 0;
 107         gfp_t   lflags = kmem_flags_convert(flags);
 108         void    *ptr;
 109
 110         do {
 111                 ptr = kmem_cache_alloc(zone, lflags);
 112                 if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP)))
 113                         return ptr;
 114                 if (!(++retries % 100))
 115                         printk(KERN_ERR "XFS: possible memory allocation "
 116                                         "deadlock in %s (mode:0x%x)\n",
 117                                         __func__, lflags);
 118                 congestion_wait(BLK_RW_ASYNC, HZ/50);
 119         } while (1);
 120 }
 121
 122 void *
 123 kmem_zone_zalloc(kmem_zone_t *zone, unsigned int __nocast flags)
 124 {
 125         void    *ptr;
 126
 127         ptr = kmem_zone_alloc(zone, flags);
 128         if (ptr)
 129                 memset((char *)ptr, 0, kmem_cache_size(zone));
 130         return ptr;
 131 }