LXR linux/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 * Must be freed using kmem_free_large.
  32 */
  33void *
  34kmem_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
  48void *
  49kmem_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
  67void *
  68kmem_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
  78void
  79kmem_free(const void *ptr)
  80{
  81        if (!is_vmalloc_addr(ptr)) {
  82                kfree(ptr);
  83        } else {
  84                vfree(ptr);
  85        }
  86}
  87
  88void *
  89kmem_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
 104void *
 105kmem_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
 123void *
 124kmem_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}
 133