LXR linux/fs/proc/nommu.c

   1/* nommu.c: mmu-less 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/init.h>
  13#include <linux/module.h>
  14#include <linux/errno.h>
  15#include <linux/time.h>
  16#include <linux/kernel.h>
  17#include <linux/string.h>
  18#include <linux/mman.h>
  19#include <linux/proc_fs.h>
  20#include <linux/mm.h>
  21#include <linux/mmzone.h>
  22#include <linux/pagemap.h>
  23#include <linux/swap.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/*
  35 * display a single region to a sequenced file
  36 */
  37static int nommu_region_show(struct seq_file *m, struct vm_region *region)
  38{
  39        unsigned long ino = 0;
  40        struct file *file;
  41        dev_t dev = 0;
  42        int flags;
  43
  44        flags = region->vm_flags;
  45        file = region->vm_file;
  46
  47        if (file) {
  48                struct inode *inode = file_inode(region->vm_file);
  49                dev = inode->i_sb->s_dev;
  50                ino = inode->i_ino;
  51        }
  52
  53        seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
  54        seq_printf(m,
  55                   "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ",
  56                   region->vm_start,
  57                   region->vm_end,
  58                   flags & VM_READ ? 'r' : '-',
  59                   flags & VM_WRITE ? 'w' : '-',
  60                   flags & VM_EXEC ? 'x' : '-',
  61                   flags & VM_MAYSHARE ? flags & VM_SHARED ? 'S' : 's' : 'p',
  62                   ((loff_t)region->vm_pgoff) << PAGE_SHIFT,
  63                   MAJOR(dev), MINOR(dev), ino);
  64
  65        if (file) {
  66                seq_pad(m, ' ');
  67                seq_path(m, &file->f_path, "");
  68        }
  69
  70        seq_putc(m, '\n');
  71        return 0;
  72}
  73
  74/*
  75 * display a list of all the REGIONs the kernel knows about
  76 * - nommu kernels have a single flat list
  77 */
  78static int nommu_region_list_show(struct seq_file *m, void *_p)
  79{
  80        struct rb_node *p = _p;
  81
  82        return nommu_region_show(m, rb_entry(p, struct vm_region, vm_rb));
  83}
  84
  85static void *nommu_region_list_start(struct seq_file *m, loff_t *_pos)
  86{
  87        struct rb_node *p;
  88        loff_t pos = *_pos;
  89
  90        down_read(&nommu_region_sem);
  91
  92        for (p = rb_first(&nommu_region_tree); p; p = rb_next(p))
  93                if (pos-- == 0)
  94                        return p;
  95        return NULL;
  96}
  97
  98static void nommu_region_list_stop(struct seq_file *m, void *v)
  99{
 100        up_read(&nommu_region_sem);
 101}
 102
 103static void *nommu_region_list_next(struct seq_file *m, void *v, loff_t *pos)
 104{
 105        (*pos)++;
 106        return rb_next((struct rb_node *) v);
 107}
 108
 109static const struct seq_operations proc_nommu_region_list_seqop = {
 110        .start  = nommu_region_list_start,
 111        .next   = nommu_region_list_next,
 112        .stop   = nommu_region_list_stop,
 113        .show   = nommu_region_list_show
 114};
 115
 116static int proc_nommu_region_list_open(struct inode *inode, struct file *file)
 117{
 118        return seq_open(file, &proc_nommu_region_list_seqop);
 119}
 120
 121static const struct file_operations proc_nommu_region_list_operations = {
 122        .open    = proc_nommu_region_list_open,
 123        .read    = seq_read,
 124        .llseek  = seq_lseek,
 125        .release = seq_release,
 126};
 127
 128static int __init proc_nommu_init(void)
 129{
 130        proc_create("maps", S_IRUGO, NULL, &proc_nommu_region_list_operations);
 131        return 0;
 132}
 133
 134fs_initcall(proc_nommu_init);
 135