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#define SYSCTL_TEST_BITMAP_SIZE 65536
  52        unsigned long *bitmap_0001;
  53};
  54
  55static struct test_sysctl_data test_data = {
  56        .int_0001 = 60,
  57        .int_0002 = 1,
  58
  59        .int_0003[0] = 0,
  60        .int_0003[1] = 1,
  61        .int_0003[2] = 2,
  62        .int_0003[3] = 3,
  63
  64        .uint_0001 = 314,
  65
  66        .string_0001 = "(none)",
  67};
  68
  69/* These are all under /proc/sys/debug/test_sysctl/ */
  70static struct ctl_table test_table[] = {
  71        {
  72                .procname       = "int_0001",
  73                .data           = &test_data.int_0001,
  74                .maxlen         = sizeof(int),
  75                .mode           = 0644,
  76                .proc_handler   = proc_dointvec_minmax,
  77                .extra1         = &i_zero,
  78                .extra2         = &i_one_hundred,
  79        },
  80        {
  81                .procname       = "int_0002",
  82                .data           = &test_data.int_0002,
  83                .maxlen         = sizeof(int),
  84                .mode           = 0644,
  85                .proc_handler   = proc_dointvec,
  86        },
  87        {
  88                .procname       = "int_0003",
  89                .data           = &test_data.int_0003,
  90                .maxlen         = sizeof(test_data.int_0003),
  91                .mode           = 0644,
  92                .proc_handler   = proc_dointvec,
  93        },
  94        {
  95                .procname       = "uint_0001",
  96                .data           = &test_data.uint_0001,
  97                .maxlen         = sizeof(unsigned int),
  98                .mode           = 0644,
  99                .proc_handler   = proc_douintvec,
 100        },
 101        {
 102                .procname       = "string_0001",
 103                .data           = &test_data.string_0001,
 104                .maxlen         = sizeof(test_data.string_0001),
 105                .mode           = 0644,
 106                .proc_handler   = proc_dostring,
 107        },
 108        {
 109                .procname       = "bitmap_0001",
 110                .data           = &test_data.bitmap_0001,
 111                .maxlen         = SYSCTL_TEST_BITMAP_SIZE,
 112                .mode           = 0644,
 113                .proc_handler   = proc_do_large_bitmap,
 114        },
 115        { }
 116};
 117
 118static struct ctl_table test_sysctl_table[] = {
 119        {
 120                .procname       = "test_sysctl",
 121                .maxlen         = 0,
 122                .mode           = 0555,
 123                .child          = test_table,
 124        },
 125        { }
 126};
 127
 128static struct ctl_table test_sysctl_root_table[] = {
 129        {
 130                .procname       = "debug",
 131                .maxlen         = 0,
 132                .mode           = 0555,
 133                .child          = test_sysctl_table,
 134        },
 135        { }
 136};
 137
 138static struct ctl_table_header *test_sysctl_header;
 139
 140static int __init test_sysctl_init(void)
 141{
 142        test_data.bitmap_0001 = kzalloc(SYSCTL_TEST_BITMAP_SIZE/8, GFP_KERNEL);
 143        if (!test_data.bitmap_0001)
 144                return -ENOMEM;
 145        test_sysctl_header = register_sysctl_table(test_sysctl_root_table);
 146        if (!test_sysctl_header) {
 147                kfree(test_data.bitmap_0001);
 148                return -ENOMEM;
 149        }
 150        return 0;
 151}
 152late_initcall(test_sysctl_init);
 153
 154static void __exit test_sysctl_exit(void)
 155{
 156        kfree(test_data.bitmap_0001);
 157        if (test_sysctl_header)
 158                unregister_sysctl_table(test_sysctl_header);
 159}
 160
 161module_exit(test_sysctl_exit);
 162
 163MODULE_AUTHOR("Luis R. Rodriguez <mcgrof@kernel.org>");
 164MODULE_LICENSE("GPL");
 165