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 #include "xfs_message.h"
  27
  28 /*
  29  * Greedy allocation.  May fail and may return vmalloced memory.
  30  *
  31  * Must be freed using kmem_free_large.
  32  */
  33 void *
  34 kmem_zalloc_greedy(size_t *size, size_t minsize, size_t maxsize)
  35 {
  36         void            *ptr;
  37         size_t          kmsize = maxsize;
  38
  39         while (!(ptr = kmem_zalloc_large(kmsize))) {
  40                 if ((kmsize >>= 1) <= minsize)
  41                         kmsize = minsize;
  42         }
  43         if (ptr)
  44                 *size = kmsize;
  45         return ptr;
  46 }
  47
  48 void *
  49 kmem_alloc(size_t size, unsigned int __nocast flags)
  50 {
  51         int     retries = 0;
  52         gfp_t   lflags = kmem_flags_convert(flags);
  53         void    *ptr;
  54
  55         do {
  56                 ptr = kmalloc(size, lflags);
  57                 if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP)))
  58                         return ptr;
  59                 if (!(++retries % 100))
  60                         xfs_err(NULL,
  61                 "possible memory allocation deadlock in %s (mode:0x%x)",
  62                                         __func__, lflags);
  63                 congestion_wait(BLK_RW_ASYNC, HZ/50);
  64         } while (1);
  65 }
  66
  67 void *
  68 kmem_zalloc(size_t size, unsigned int __nocast flags)
  69 {
  70         void    *ptr;
  71
  72         ptr = kmem_alloc(size, flags);
  73         if (ptr)
  74                 memset((char *)ptr, 0, (int)size);
  75         return ptr;
  76 }
  77
  78 void
  79 kmem_free(const void *ptr)
  80 {
  81         if (!is_vmalloc_addr(ptr)) {
  82                 kfree(ptr);
  83         } else {
  84                 vfree(ptr);
  85         }
  86 }
  87
  88 void *
  89 kmem_realloc(const void *ptr, size_t newsize, size_t oldsize,
  90              unsigned int __nocast flags)
  91 {
  92         void    *new;
  93
  94         new = kmem_alloc(newsize, flags);
  95         if (ptr) {
  96                 if (new)
  97                         memcpy(new, ptr,
  98                                 ((oldsize < newsize) ? oldsize : newsize));
  99                 kmem_free(ptr);
 100         }
 101         return new;
 102 }
 103
 104 void *
 105 kmem_zone_alloc(kmem_zone_t *zone, unsigned int __nocast flags)
 106 {
 107         int     retries = 0;
 108         gfp_t   lflags = kmem_flags_convert(flags);
 109         void    *ptr;
 110
 111         do {
 112                 ptr = kmem_cache_alloc(zone, lflags);
 113                 if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP)))
 114                         return ptr;
 115                 if (!(++retries % 100))
 116                         xfs_err(NULL,
 117                 "possible memory allocation deadlock in %s (mode:0x%x)",
 118                                         __func__, lflags);
 119                 congestion_wait(BLK_RW_ASYNC, HZ/50);
 120         } while (1);
 121 }
 122
 123 void *
 124 kmem_zone_zalloc(kmem_zone_t *zone, unsigned int __nocast flags)
 125 {
 126         void    *ptr;
 127
 128         ptr = kmem_zone_alloc(zone, flags);
 129         if (ptr)
 130                 memset((char *)ptr, 0, kmem_cache_size(zone));
 131         return ptr;
 132 }