LXR linux/lib/test

   1/*
   2 * proc sysctl test driver
   3 *
   4 * Copyright (C) 2017 Luis R. Rodriguez <mcgrof@kernel.org>
   5 *
   6 * This program is free software; you can redistribute it and/or modify it
   7 * under the terms of the GNU General Public License as published by the Free
   8 * Software Foundation; either version 2 of the License, or at your option any
   9 * later version; or, when distributed separately from the Linux kernel or
  10 * when incorporated into other software packages, subject to the following
  11 * license:
  12 *
  13 * This program is free software; you can redistribute it and/or modify it
  14 * under the terms of copyleft-next (version 0.3.1 or later) as published
  15 * at http://copyleft-next.org/.
  16 */
  17
  18/*
  19 * This module provides an interface to the the proc sysctl interfaces.  This
  20 * driver requires CONFIG_PROC_SYSCTL. It will not normally be loaded by the
  21 * system unless explicitly requested by name. You can also build this driver
  22 * into your kernel.
  23 */
  24
  25#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  26
  27#include <linux/init.h>
  28#include <linux/list.h>
  29#include <linux/module.h>
  30#include <linux/printk.h>
  31#include <linux/fs.h>
  32#include <linux/miscdevice.h>
  33#include <linux/slab.h>
  34#include <linux/uaccess.h>
  35#include <linux/async.h>
  36#include <linux/delay.h>
  37#include <linux/vmalloc.h>
  38
  39static int i_zero;
  40static int i_one_hundred = 100;
  41
  42struct test_sysctl_data {
  43        int int_0001;
  44        int int_0002;
  45        int int_0003[4];
  46
  47        unsigned int uint_0001;
  48
  49        char string_0001[65];
  50};
  51
  52static struct test_sysctl_data test_data = {
  53        .int_0001 = 60,
  54        .int_0002 = 1,
  55
  56        .int_0003[0] = 0,
  57        .int_0003[1] = 1,
  58        .int_0003[2] = 2,
  59        .int_0003[3] = 3,
  60
  61        .uint_0001 = 314,
  62
  63        .string_0001 = "(none)",
  64};
  65
  66/* These are all under /proc/sys/debug/test_sysctl/ */
  67static struct ctl_table test_table[] = {
  68        {
  69                .procname       = "int_0001",
  70                .data           = &test_data.int_0001,
  71                .maxlen         = sizeof(int),
  72                .mode           = 0644,
  73                .proc_handler   = proc_dointvec_minmax,
  74                .extra1         = &i_zero,
  75                .extra2         = &i_one_hundred,
  76        },
  77        {
  78                .procname       = "int_0002",
  79                .data           = &test_data.int_0002,
  80                .maxlen         = sizeof(int),
  81                .mode           = 0644,
  82                .proc_handler   = proc_dointvec,
  83        },
  84        {
  85                .procname       = "int_0003",
  86                .data           = &test_data.int_0003,
  87                .maxlen         = sizeof(test_data.int_0003),
  88                .mode           = 0644,
  89                .proc_handler   = proc_dointvec,
  90        },
  91        {
  92                .procname       = "uint_0001",
  93                .data           = &test_data.uint_0001,
  94                .maxlen         = sizeof(unsigned int),
  95                .mode           = 0644,
  96                .proc_handler   = proc_douintvec,
  97        },
  98        {
  99                .procname       = "string_0001",
 100                .data           = &test_data.string_0001,
 101                .maxlen         = sizeof(test_data.string_0001),
 102                .mode           = 0644,
 103                .proc_handler   = proc_dostring,
 104        },
 105        { }
 106};
 107
 108static struct ctl_table test_sysctl_table[] = {
 109        {
 110                .procname       = "test_sysctl",
 111                .maxlen         = 0,
 112                .mode           = 0555,
 113                .child          = test_table,
 114        },
 115        { }
 116};
 117
 118static struct ctl_table test_sysctl_root_table[] = {
 119        {
 120                .procname       = "debug",
 121                .maxlen         = 0,
 122                .mode           = 0555,
 123                .child          = test_sysctl_table,
 124        },
 125        { }
 126};
 127
 128static struct ctl_table_header *test_sysctl_header;
 129
 130static int __init test_sysctl_init(void)
 131{
 132        test_sysctl_header = register_sysctl_table(test_sysctl_root_table);
 133        if (!test_sysctl_header)
 134                return -ENOMEM;
 135        return 0;
 136}
 137late_initcall(test_sysctl_init);
 138
 139static void __exit test_sysctl_exit(void)
 140{
 141        if (test_sysctl_header)
 142                unregister_sysctl_table(test_sysctl_header);
 143}
 144
 145module_exit(test_sysctl_exit);
 146
 147MODULE_AUTHOR("Luis R. Rodriguez <mcgrof@kernel.org>");
 148MODULE_LICENSE("GPL");
 149