fs/proc/mmu.c

   1 /* mmu.c: mmu memory info files
   2  *
   3  * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <linux/types.h>
  13 #include <linux/errno.h>
  14 #include <linux/time.h>
  15 #include <linux/kernel.h>
  16 #include <linux/string.h>
  17 #include <linux/mman.h>
  18 #include <linux/proc_fs.h>
  19 #include <linux/mm.h>
  20 #include <linux/mmzone.h>
  21 #include <linux/pagemap.h>
  22 #include <linux/swap.h>
  23 #include <linux/slab.h>
  24 #include <linux/smp.h>
  25 #include <linux/seq_file.h>
  26 #include <linux/hugetlb.h>
  27 #include <linux/vmalloc.h>
  28 #include <asm/uaccess.h>
  29 #include <asm/pgtable.h>
  30 #include <asm/tlb.h>
  31 #include <asm/div64.h>
  32 #include "internal.h"
  33
  34 void get_vmalloc_info(struct vmalloc_info *vmi)
  35 {
  36         struct vm_struct *vma;
  37         unsigned long free_area_size;
  38         unsigned long prev_end;
  39
  40         vmi->used = 0;
  41
  42         if (!vmlist) {
  43                 vmi->largest_chunk = VMALLOC_TOTAL;
  44         }
  45         else {
  46                 vmi->largest_chunk = 0;
  47
  48                 prev_end = VMALLOC_START;
  49
  50                 read_lock(&vmlist_lock);
  51
  52                 for (vma = vmlist; vma; vma = vma->next) {
  53                         unsigned long addr = (unsigned long) vma->addr;
  54
  55                         /*
  56                          * Some archs keep another range for modules in vmlist
  57                          */
  58                         if (addr < VMALLOC_START)
  59                                 continue;
  60                         if (addr >= VMALLOC_END)
  61                                 break;
  62
  63                         vmi->used += vma->size;
  64
  65                         free_area_size = addr - prev_end;
  66                         if (vmi->largest_chunk < free_area_size)
  67                                 vmi->largest_chunk = free_area_size;
  68
  69                         prev_end = vma->size + addr;
  70                 }
  71
  72                 if (VMALLOC_END - prev_end > vmi->largest_chunk)
  73                         vmi->largest_chunk = VMALLOC_END - prev_end;
  74
  75                 read_unlock(&vmlist_lock);
  76         }
  77 }