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. */
37static struct ctl_table ntfs_sysctls[] = {
38	{
39		.procname	= "ntfs-debug",
40		.data		= &debug_msgs,		/* Data pointer and size. */
41		.maxlen		= sizeof(debug_msgs),
42		.mode		= 0644,			/* Mode, proc handler. */
43		.proc_handler	= proc_dointvec
44	},
45	{}
46};
47
48/* Define the parent directory /proc/sys/fs. */
49static struct ctl_table sysctls_root[] = {
50	{
51		.procname	= "fs",
52		.mode		= 0555,
53		.child		= ntfs_sysctls
54	},
55	{}
56};
57
58/* Storage for the sysctls header. */
59static struct ctl_table_header *sysctls_root_table;
60
61/**
62 * ntfs_sysctl - add or remove the debug sysctl
63 * @add:	add (1) or remove (0) the sysctl
64 *
65 * Add or remove the debug sysctl. Return 0 on success or -errno on error.
66 */
67int ntfs_sysctl(int add)
68{
69	if (add) {
70		BUG_ON(sysctls_root_table);
71		sysctls_root_table = register_sysctl_table(sysctls_root);
72		if (!sysctls_root_table)
73			return -ENOMEM;
74	} else {
75		BUG_ON(!sysctls_root_table);
76		unregister_sysctl_table(sysctls_root_table);
77		sysctls_root_table = NULL;
78	}
79	return 0;
80}
81
82#endif /* CONFIG_SYSCTL */
83#endif /* DEBUG */
84