fs/xfs/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 void *
  32 kmem_zalloc_greedy(size_t *size, size_t minsize, size_t maxsize)
  33 {
  34         void            *ptr;
  35         size_t          kmsize = maxsize;
  36
  37         while (!(ptr = vzalloc(kmsize))) {
  38                 if ((kmsize >>= 1) <= minsize)
  39                         kmsize = minsize;
  40         }
  41         if (ptr)
  42                 *size = kmsize;
  43         return ptr;
  44 }
  45
  46 void *
  47 kmem_alloc(size_t size, xfs_km_flags_t flags)
  48 {
  49         int     retries = 0;
  50         gfp_t   lflags = kmem_flags_convert(flags);
  51         void    *ptr;
  52
  53         do {
  54                 ptr = kmalloc(size, lflags);
  55                 if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP)))
  56                         return ptr;
  57                 if (!(++retries % 100))
  58                         xfs_err(NULL,
  59                 "possible memory allocation deadlock in %s (mode:0x%x)",
  60                                         __func__, lflags);
  61                 congestion_wait(BLK_RW_ASYNC, HZ/50);
  62         } while (1);
  63 }
  64
  65 void *
  66 kmem_zalloc_large(size_t size, xfs_km_flags_t flags)
  67 {
  68         void    *ptr;
  69
  70         ptr = kmem_zalloc(size, flags | KM_MAYFAIL);
  71         if (ptr)
  72                 return ptr;
  73         return vzalloc(size);
  74 }
  75
  76 void
  77 kmem_free(const void *ptr)
  78 {
  79         if (!is_vmalloc_addr(ptr)) {
  80                 kfree(ptr);
  81         } else {
  82                 vfree(ptr);
  83         }
  84 }
  85
  86 void *
  87 kmem_realloc(const void *ptr, size_t newsize, size_t oldsize,
  88              xfs_km_flags_t flags)
  89 {
  90         void    *new;
  91
  92         new = kmem_alloc(newsize, flags);
  93         if (ptr) {
  94                 if (new)
  95                         memcpy(new, ptr,
  96                                 ((oldsize < newsize) ? oldsize : newsize));
  97                 kmem_free(ptr);
  98         }
  99         return new;
 100 }
 101
 102 void *
 103 kmem_zone_alloc(kmem_zone_t *zone, xfs_km_flags_t flags)
 104 {
 105         int     retries = 0;
 106         gfp_t   lflags = kmem_flags_convert(flags);
 107         void    *ptr;
 108
 109         do {
 110                 ptr = kmem_cache_alloc(zone, lflags);
 111                 if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP)))
 112                         return ptr;
 113                 if (!(++retries % 100))
 114                         xfs_err(NULL,
 115                 "possible memory allocation deadlock in %s (mode:0x%x)",
 116                                         __func__, lflags);
 117                 congestion_wait(BLK_RW_ASYNC, HZ/50);
 118         } while (1);
 119 }