1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * sysctl.c - Code for sysctl handling in NTFS Linux kernel driver. Part of 4 * the Linux-NTFS project. Adapted from the old NTFS driver, 5 * Copyright (C) 1997 Martin von Löwis, Régis Duchesne 6 * 7 * Copyright (c) 2002-2005 Anton Altaparmakov 8 */ 9 10 #ifdef DEBUG 11 12 #include <linux/module.h> 13 14 #ifdef CONFIG_SYSCTL 15 16 #include <linux/proc_fs.h> 17 #include <linux/sysctl.h> 18 19 #include "sysctl.h" 20 #include "debug.h" 21 22 /* Definition of the ntfs sysctl. */ 23 static struct ctl_table ntfs_sysctls[] = { 24 { 25 .procname = "ntfs-debug", 26 .data = &debug_msgs, /* Data pointer and size. */ 27 .maxlen = sizeof(debug_msgs), 28 .mode = 0644, /* Mode, proc handler. */ 29 .proc_handler = proc_dointvec 30 }, 31 {} 32 }; 33 34 /* Storage for the sysctls header. */ 35 static struct ctl_table_header *sysctls_root_table; 36 37 /** 38 * ntfs_sysctl - add or remove the debug sysctl 39 * @add: add (1) or remove (0) the sysctl 40 * 41 * Add or remove the debug sysctl. Return 0 on success or -errno on error. 42 */ 43 int ntfs_sysctl(int add) 44 { 45 if (add) { 46 BUG_ON(sysctls_root_table); 47 sysctls_root_table = register_sysctl("fs", ntfs_sysctls); 48 if (!sysctls_root_table) 49 return -ENOMEM; 50 } else { 51 BUG_ON(!sysctls_root_table); 52 unregister_sysctl_table(sysctls_root_table); 53 sysctls_root_table = NULL; 54 } 55 return 0; 56 } 57 58 #endif /* CONFIG_SYSCTL */ 59 #endif /* DEBUG */ 60