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-rw-r--r--drivers/char/watchdog/softdog.c310
1 files changed, 0 insertions, 310 deletions
diff --git a/drivers/char/watchdog/softdog.c b/drivers/char/watchdog/softdog.c
deleted file mode 100644
index 9c3694909243..000000000000
--- a/drivers/char/watchdog/softdog.c
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@@ -1,310 +0,0 @@
1/*
2 * SoftDog 0.07: A Software Watchdog Device
3 *
4 * (c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved.
5 * http://www.redhat.com
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 *
12 * Neither Alan Cox nor CymruNet Ltd. admit liability nor provide
13 * warranty for any of this software. This material is provided
14 * "AS-IS" and at no charge.
15 *
16 * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk>
17 *
18 * Software only watchdog driver. Unlike its big brother the WDT501P
19 * driver this won't always recover a failed machine.
20 *
21 * 03/96: Angelo Haritsis <ah@doc.ic.ac.uk> :
22 * Modularised.
23 * Added soft_margin; use upon insmod to change the timer delay.
24 * NB: uses same minor as wdt (WATCHDOG_MINOR); we could use separate
25 * minors.
26 *
27 * 19980911 Alan Cox
28 * Made SMP safe for 2.3.x
29 *
30 * 20011127 Joel Becker (jlbec@evilplan.org>
31 * Added soft_noboot; Allows testing the softdog trigger without
32 * requiring a recompile.
33 * Added WDIOC_GETTIMEOUT and WDIOC_SETTIMOUT.
34 *
35 * 20020530 Joel Becker <joel.becker@oracle.com>
36 * Added Matt Domsch's nowayout module option.
37 */
38
39#include <linux/module.h>
40#include <linux/moduleparam.h>
41#include <linux/types.h>
42#include <linux/timer.h>
43#include <linux/miscdevice.h>
44#include <linux/watchdog.h>
45#include <linux/fs.h>
46#include <linux/notifier.h>
47#include <linux/reboot.h>
48#include <linux/init.h>
49#include <linux/jiffies.h>
50
51#include <asm/uaccess.h>
52
53#define PFX "SoftDog: "
54
55#define TIMER_MARGIN 60 /* Default is 60 seconds */
56static int soft_margin = TIMER_MARGIN; /* in seconds */
57module_param(soft_margin, int, 0);
58MODULE_PARM_DESC(soft_margin, "Watchdog soft_margin in seconds. (0<soft_margin<65536, default=" __MODULE_STRING(TIMER_MARGIN) ")");
59
60static int nowayout = WATCHDOG_NOWAYOUT;
61module_param(nowayout, int, 0);
62MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
63
64#ifdef ONLY_TESTING
65static int soft_noboot = 1;
66#else
67static int soft_noboot = 0;
68#endif /* ONLY_TESTING */
69
70module_param(soft_noboot, int, 0);
71MODULE_PARM_DESC(soft_noboot, "Softdog action, set to 1 to ignore reboots, 0 to reboot (default depends on ONLY_TESTING)");
72
73/*
74 * Our timer
75 */
76
77static void watchdog_fire(unsigned long);
78
79static struct timer_list watchdog_ticktock =
80 TIMER_INITIALIZER(watchdog_fire, 0, 0);
81static unsigned long driver_open, orphan_timer;
82static char expect_close;
83
84
85/*
86 * If the timer expires..
87 */
88
89static void watchdog_fire(unsigned long data)
90{
91 if (test_and_clear_bit(0, &orphan_timer))
92 module_put(THIS_MODULE);
93
94 if (soft_noboot)
95 printk(KERN_CRIT PFX "Triggered - Reboot ignored.\n");
96 else
97 {
98 printk(KERN_CRIT PFX "Initiating system reboot.\n");
99 emergency_restart();
100 printk(KERN_CRIT PFX "Reboot didn't ?????\n");
101 }
102}
103
104/*
105 * Softdog operations
106 */
107
108static int softdog_keepalive(void)
109{
110 mod_timer(&watchdog_ticktock, jiffies+(soft_margin*HZ));
111 return 0;
112}
113
114static int softdog_stop(void)
115{
116 del_timer(&watchdog_ticktock);
117 return 0;
118}
119
120static int softdog_set_heartbeat(int t)
121{
122 if ((t < 0x0001) || (t > 0xFFFF))
123 return -EINVAL;
124
125 soft_margin = t;
126 return 0;
127}
128
129/*
130 * /dev/watchdog handling
131 */
132
133static int softdog_open(struct inode *inode, struct file *file)
134{
135 if (test_and_set_bit(0, &driver_open))
136 return -EBUSY;
137 if (!test_and_clear_bit(0, &orphan_timer))
138 __module_get(THIS_MODULE);
139 /*
140 * Activate timer
141 */
142 softdog_keepalive();
143 return nonseekable_open(inode, file);
144}
145
146static int softdog_release(struct inode *inode, struct file *file)
147{
148 /*
149 * Shut off the timer.
150 * Lock it in if it's a module and we set nowayout
151 */
152 if (expect_close == 42) {
153 softdog_stop();
154 module_put(THIS_MODULE);
155 } else {
156 printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
157 set_bit(0, &orphan_timer);
158 softdog_keepalive();
159 }
160 clear_bit(0, &driver_open);
161 expect_close = 0;
162 return 0;
163}
164
165static ssize_t softdog_write(struct file *file, const char __user *data, size_t len, loff_t *ppos)
166{
167 /*
168 * Refresh the timer.
169 */
170 if(len) {
171 if (!nowayout) {
172 size_t i;
173
174 /* In case it was set long ago */
175 expect_close = 0;
176
177 for (i = 0; i != len; i++) {
178 char c;
179
180 if (get_user(c, data + i))
181 return -EFAULT;
182 if (c == 'V')
183 expect_close = 42;
184 }
185 }
186 softdog_keepalive();
187 }
188 return len;
189}
190
191static int softdog_ioctl(struct inode *inode, struct file *file,
192 unsigned int cmd, unsigned long arg)
193{
194 void __user *argp = (void __user *)arg;
195 int __user *p = argp;
196 int new_margin;
197 static struct watchdog_info ident = {
198 .options = WDIOF_SETTIMEOUT |
199 WDIOF_KEEPALIVEPING |
200 WDIOF_MAGICCLOSE,
201 .firmware_version = 0,
202 .identity = "Software Watchdog",
203 };
204 switch (cmd) {
205 default:
206 return -ENOTTY;
207 case WDIOC_GETSUPPORT:
208 return copy_to_user(argp, &ident,
209 sizeof(ident)) ? -EFAULT : 0;
210 case WDIOC_GETSTATUS:
211 case WDIOC_GETBOOTSTATUS:
212 return put_user(0, p);
213 case WDIOC_KEEPALIVE:
214 softdog_keepalive();
215 return 0;
216 case WDIOC_SETTIMEOUT:
217 if (get_user(new_margin, p))
218 return -EFAULT;
219 if (softdog_set_heartbeat(new_margin))
220 return -EINVAL;
221 softdog_keepalive();
222 /* Fall */
223 case WDIOC_GETTIMEOUT:
224 return put_user(soft_margin, p);
225 }
226}
227
228/*
229 * Notifier for system down
230 */
231
232static int softdog_notify_sys(struct notifier_block *this, unsigned long code,
233 void *unused)
234{
235 if(code==SYS_DOWN || code==SYS_HALT) {
236 /* Turn the WDT off */
237 softdog_stop();
238 }
239 return NOTIFY_DONE;
240}
241
242/*
243 * Kernel Interfaces
244 */
245
246static const struct file_operations softdog_fops = {
247 .owner = THIS_MODULE,
248 .llseek = no_llseek,
249 .write = softdog_write,
250 .ioctl = softdog_ioctl,
251 .open = softdog_open,
252 .release = softdog_release,
253};
254
255static struct miscdevice softdog_miscdev = {
256 .minor = WATCHDOG_MINOR,
257 .name = "watchdog",
258 .fops = &softdog_fops,
259};
260
261static struct notifier_block softdog_notifier = {
262 .notifier_call = softdog_notify_sys,
263};
264
265static char banner[] __initdata = KERN_INFO "Software Watchdog Timer: 0.07 initialized. soft_noboot=%d soft_margin=%d sec (nowayout= %d)\n";
266
267static int __init watchdog_init(void)
268{
269 int ret;
270
271 /* Check that the soft_margin value is within it's range ; if not reset to the default */
272 if (softdog_set_heartbeat(soft_margin)) {
273 softdog_set_heartbeat(TIMER_MARGIN);
274 printk(KERN_INFO PFX "soft_margin value must be 0<soft_margin<65536, using %d\n",
275 TIMER_MARGIN);
276 }
277
278 ret = register_reboot_notifier(&softdog_notifier);
279 if (ret) {
280 printk (KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
281 ret);
282 return ret;
283 }
284
285 ret = misc_register(&softdog_miscdev);
286 if (ret) {
287 printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
288 WATCHDOG_MINOR, ret);
289 unregister_reboot_notifier(&softdog_notifier);
290 return ret;
291 }
292
293 printk(banner, soft_noboot, soft_margin, nowayout);
294
295 return 0;
296}
297
298static void __exit watchdog_exit(void)
299{
300 misc_deregister(&softdog_miscdev);
301 unregister_reboot_notifier(&softdog_notifier);
302}
303
304module_init(watchdog_init);
305module_exit(watchdog_exit);
306
307MODULE_AUTHOR("Alan Cox");
308MODULE_DESCRIPTION("Software Watchdog Device Driver");
309MODULE_LICENSE("GPL");
310MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-18 10:14:51 -0500