LXR linux/arch/powerpc/kernel/proc

   1/*
   2 * Copyright (C) 2001 Mike Corrigan & Dave Engebretsen IBM Corporation
   3 *
   4 * This program is free software; you can redistribute it and/or modify
   5 * it under the terms of the GNU General Public License as published by
   6 * the Free Software Foundation; either version 2 of the License, or
   7 * (at your option) any later version.
   8 *
   9 * This program is distributed in the hope that it will 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 to the Free Software
  16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  17 */
  18
  19#include <linux/init.h>
  20#include <linux/mm.h>
  21#include <linux/proc_fs.h>
  22#include <linux/kernel.h>
  23
  24#include <asm/machdep.h>
  25#include <asm/vdso_datapage.h>
  26#include <asm/rtas.h>
  27#include <linux/uaccess.h>
  28#include <asm/prom.h>
  29
  30#ifdef CONFIG_PPC64
  31
  32static loff_t page_map_seek(struct file *file, loff_t off, int whence)
  33{
  34        return fixed_size_llseek(file, off, whence, PAGE_SIZE);
  35}
  36
  37static ssize_t page_map_read( struct file *file, char __user *buf, size_t nbytes,
  38                              loff_t *ppos)
  39{
  40        return simple_read_from_buffer(buf, nbytes, ppos,
  41                        PDE_DATA(file_inode(file)), PAGE_SIZE);
  42}
  43
  44static int page_map_mmap( struct file *file, struct vm_area_struct *vma )
  45{
  46        if ((vma->vm_end - vma->vm_start) > PAGE_SIZE)
  47                return -EINVAL;
  48
  49        remap_pfn_range(vma, vma->vm_start,
  50                        __pa(PDE_DATA(file_inode(file))) >> PAGE_SHIFT,
  51                        PAGE_SIZE, vma->vm_page_prot);
  52        return 0;
  53}
  54
  55static const struct file_operations page_map_fops = {
  56        .llseek = page_map_seek,
  57        .read   = page_map_read,
  58        .mmap   = page_map_mmap
  59};
  60
  61
  62static int __init proc_ppc64_init(void)
  63{
  64        struct proc_dir_entry *pde;
  65
  66        pde = proc_create_data("powerpc/systemcfg", S_IFREG|S_IRUGO, NULL,
  67                               &page_map_fops, vdso_data);
  68        if (!pde)
  69                return 1;
  70        proc_set_size(pde, PAGE_SIZE);
  71
  72        return 0;
  73}
  74__initcall(proc_ppc64_init);
  75
  76#endif /* CONFIG_PPC64 */
  77
  78/*
  79 * Create the ppc64 and ppc64/rtas directories early. This allows us to
  80 * assume that they have been previously created in drivers.
  81 */
  82static int __init proc_ppc64_create(void)
  83{
  84        struct proc_dir_entry *root;
  85
  86        root = proc_mkdir("powerpc", NULL);
  87        if (!root)
  88                return 1;
  89
  90#ifdef CONFIG_PPC64
  91        if (!proc_symlink("ppc64", NULL, "powerpc"))
  92                pr_err("Failed to create link /proc/ppc64 -> /proc/powerpc\n");
  93#endif
  94
  95        if (!of_find_node_by_path("/rtas"))
  96                return 0;
  97
  98        if (!proc_mkdir("rtas", root))
  99                return 1;
 100
 101        if (!proc_symlink("rtas", NULL, "powerpc/rtas"))
 102                return 1;
 103
 104        return 0;
 105}
 106core_initcall(proc_ppc64_create);
 107