fs/ntfs/sysctl.c

   1 /*
   2  * sysctl.c - Code for sysctl handling in NTFS Linux kernel driver. Part of
   3  *            the Linux-NTFS project. Adapted from the old NTFS driver,
   4  *            Copyright (C) 1997 Martin von Löwis, Régis Duchesne
   5  *
   6  * Copyright (c) 2002-2005 Anton Altaparmakov
   7  *
   8  * This program/include file is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as published
  10  * by the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program/include file is distributed in the hope that it will be
  14  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  15  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program (in the main directory of the Linux-NTFS
  20  * distribution in the file COPYING); if not, write to the Free Software
  21  * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  22  */
  23
  24 #ifdef DEBUG
  25
  26 #include <linux/module.h>
  27
  28 #ifdef CONFIG_SYSCTL
  29
  30 #include <linux/proc_fs.h>
  31 #include <linux/sysctl.h>
  32
  33 #include "sysctl.h"
  34 #include "debug.h"
  35
  36 /* Definition of the ntfs sysctl. */
  37 static ctl_table ntfs_sysctls[] = {
  38         {
  39                 .ctl_name       = CTL_UNNUMBERED,       /* Binary and text IDs. */
  40                 .procname       = "ntfs-debug",
  41                 .data           = &debug_msgs,          /* Data pointer and size. */
  42                 .maxlen         = sizeof(debug_msgs),
  43                 .mode           = 0644,                 /* Mode, proc handler. */
  44                 .proc_handler   = &proc_dointvec
  45         },
  46         {}
  47 };
  48
  49 /* Define the parent directory /proc/sys/fs. */
  50 static ctl_table sysctls_root[] = {
  51         {
  52                 .ctl_name       = CTL_FS,
  53                 .procname       = "fs",
  54                 .mode           = 0555,
  55                 .child          = ntfs_sysctls
  56         },
  57         {}
  58 };
  59
  60 /* Storage for the sysctls header. */
  61 static struct ctl_table_header *sysctls_root_table = NULL;
  62
  63 /**
  64  * ntfs_sysctl - add or remove the debug sysctl
  65  * @add:        add (1) or remove (0) the sysctl
  66  *
  67  * Add or remove the debug sysctl. Return 0 on success or -errno on error.
  68  */
  69 int ntfs_sysctl(int add)
  70 {
  71         if (add) {
  72                 BUG_ON(sysctls_root_table);
  73                 sysctls_root_table = register_sysctl_table(sysctls_root);
  74                 if (!sysctls_root_table)
  75                         return -ENOMEM;
  76         } else {
  77                 BUG_ON(!sysctls_root_table);
  78                 unregister_sysctl_table(sysctls_root_table);
  79                 sysctls_root_table = NULL;
  80         }
  81         return 0;
  82 }
  83
  84 #endif /* CONFIG_SYSCTL */
  85 #endif /* DEBUG */