diff options
Diffstat (limited to 'drivers/watchdog/softdog.c')
-rw-r--r-- | drivers/watchdog/softdog.c | 211 |
1 files changed, 47 insertions, 164 deletions
diff --git a/drivers/watchdog/softdog.c b/drivers/watchdog/softdog.c index bf16ffb4d21e..fe83beb8f1b7 100644 --- a/drivers/watchdog/softdog.c +++ b/drivers/watchdog/softdog.c | |||
@@ -1,5 +1,5 @@ | |||
1 | /* | 1 | /* |
2 | * SoftDog 0.07: A Software Watchdog Device | 2 | * SoftDog: A Software Watchdog Device |
3 | * | 3 | * |
4 | * (c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>, | 4 | * (c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>, |
5 | * All Rights Reserved. | 5 | * All Rights Reserved. |
@@ -36,45 +36,37 @@ | |||
36 | * Added Matt Domsch's nowayout module option. | 36 | * Added Matt Domsch's nowayout module option. |
37 | */ | 37 | */ |
38 | 38 | ||
39 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | ||
40 | |||
39 | #include <linux/module.h> | 41 | #include <linux/module.h> |
40 | #include <linux/moduleparam.h> | 42 | #include <linux/moduleparam.h> |
41 | #include <linux/types.h> | 43 | #include <linux/types.h> |
42 | #include <linux/timer.h> | 44 | #include <linux/timer.h> |
43 | #include <linux/miscdevice.h> | 45 | #include <linux/miscdevice.h> |
44 | #include <linux/watchdog.h> | 46 | #include <linux/watchdog.h> |
45 | #include <linux/fs.h> | ||
46 | #include <linux/notifier.h> | 47 | #include <linux/notifier.h> |
47 | #include <linux/reboot.h> | 48 | #include <linux/reboot.h> |
48 | #include <linux/init.h> | 49 | #include <linux/init.h> |
49 | #include <linux/jiffies.h> | 50 | #include <linux/jiffies.h> |
50 | #include <linux/uaccess.h> | ||
51 | #include <linux/kernel.h> | 51 | #include <linux/kernel.h> |
52 | 52 | ||
53 | #define PFX "SoftDog: " | ||
54 | |||
55 | #define TIMER_MARGIN 60 /* Default is 60 seconds */ | 53 | #define TIMER_MARGIN 60 /* Default is 60 seconds */ |
56 | static int soft_margin = TIMER_MARGIN; /* in seconds */ | 54 | static unsigned int soft_margin = TIMER_MARGIN; /* in seconds */ |
57 | module_param(soft_margin, int, 0); | 55 | module_param(soft_margin, uint, 0); |
58 | MODULE_PARM_DESC(soft_margin, | 56 | MODULE_PARM_DESC(soft_margin, |
59 | "Watchdog soft_margin in seconds. (0 < soft_margin < 65536, default=" | 57 | "Watchdog soft_margin in seconds. (0 < soft_margin < 65536, default=" |
60 | __MODULE_STRING(TIMER_MARGIN) ")"); | 58 | __MODULE_STRING(TIMER_MARGIN) ")"); |
61 | 59 | ||
62 | static int nowayout = WATCHDOG_NOWAYOUT; | 60 | static bool nowayout = WATCHDOG_NOWAYOUT; |
63 | module_param(nowayout, int, 0); | 61 | module_param(nowayout, bool, 0); |
64 | MODULE_PARM_DESC(nowayout, | 62 | MODULE_PARM_DESC(nowayout, |
65 | "Watchdog cannot be stopped once started (default=" | 63 | "Watchdog cannot be stopped once started (default=" |
66 | __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); | 64 | __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); |
67 | 65 | ||
68 | #ifdef ONLY_TESTING | ||
69 | static int soft_noboot = 1; | ||
70 | #else | ||
71 | static int soft_noboot = 0; | 66 | static int soft_noboot = 0; |
72 | #endif /* ONLY_TESTING */ | ||
73 | |||
74 | module_param(soft_noboot, int, 0); | 67 | module_param(soft_noboot, int, 0); |
75 | MODULE_PARM_DESC(soft_noboot, | 68 | MODULE_PARM_DESC(soft_noboot, |
76 | "Softdog action, set to 1 to ignore reboots, 0 to reboot " | 69 | "Softdog action, set to 1 to ignore reboots, 0 to reboot (default=0)"); |
77 | "(default depends on ONLY_TESTING)"); | ||
78 | 70 | ||
79 | static int soft_panic; | 71 | static int soft_panic; |
80 | module_param(soft_panic, int, 0); | 72 | module_param(soft_panic, int, 0); |
@@ -89,9 +81,6 @@ static void watchdog_fire(unsigned long); | |||
89 | 81 | ||
90 | static struct timer_list watchdog_ticktock = | 82 | static struct timer_list watchdog_ticktock = |
91 | TIMER_INITIALIZER(watchdog_fire, 0, 0); | 83 | TIMER_INITIALIZER(watchdog_fire, 0, 0); |
92 | static unsigned long driver_open, orphan_timer; | ||
93 | static char expect_close; | ||
94 | |||
95 | 84 | ||
96 | /* | 85 | /* |
97 | * If the timer expires.. | 86 | * If the timer expires.. |
@@ -99,18 +88,15 @@ static char expect_close; | |||
99 | 88 | ||
100 | static void watchdog_fire(unsigned long data) | 89 | static void watchdog_fire(unsigned long data) |
101 | { | 90 | { |
102 | if (test_and_clear_bit(0, &orphan_timer)) | ||
103 | module_put(THIS_MODULE); | ||
104 | |||
105 | if (soft_noboot) | 91 | if (soft_noboot) |
106 | printk(KERN_CRIT PFX "Triggered - Reboot ignored.\n"); | 92 | pr_crit("Triggered - Reboot ignored\n"); |
107 | else if (soft_panic) { | 93 | else if (soft_panic) { |
108 | printk(KERN_CRIT PFX "Initiating panic.\n"); | 94 | pr_crit("Initiating panic\n"); |
109 | panic("Software Watchdog Timer expired."); | 95 | panic("Software Watchdog Timer expired"); |
110 | } else { | 96 | } else { |
111 | printk(KERN_CRIT PFX "Initiating system reboot.\n"); | 97 | pr_crit("Initiating system reboot\n"); |
112 | emergency_restart(); | 98 | emergency_restart(); |
113 | printk(KERN_CRIT PFX "Reboot didn't ?????\n"); | 99 | pr_crit("Reboot didn't ?????\n"); |
114 | } | 100 | } |
115 | } | 101 | } |
116 | 102 | ||
@@ -118,127 +104,24 @@ static void watchdog_fire(unsigned long data) | |||
118 | * Softdog operations | 104 | * Softdog operations |
119 | */ | 105 | */ |
120 | 106 | ||
121 | static int softdog_keepalive(void) | 107 | static int softdog_ping(struct watchdog_device *w) |
122 | { | 108 | { |
123 | mod_timer(&watchdog_ticktock, jiffies+(soft_margin*HZ)); | 109 | mod_timer(&watchdog_ticktock, jiffies+(w->timeout*HZ)); |
124 | return 0; | 110 | return 0; |
125 | } | 111 | } |
126 | 112 | ||
127 | static int softdog_stop(void) | 113 | static int softdog_stop(struct watchdog_device *w) |
128 | { | 114 | { |
129 | del_timer(&watchdog_ticktock); | 115 | del_timer(&watchdog_ticktock); |
130 | return 0; | 116 | return 0; |
131 | } | 117 | } |
132 | 118 | ||
133 | static int softdog_set_heartbeat(int t) | 119 | static int softdog_set_timeout(struct watchdog_device *w, unsigned int t) |
134 | { | ||
135 | if ((t < 0x0001) || (t > 0xFFFF)) | ||
136 | return -EINVAL; | ||
137 | |||
138 | soft_margin = t; | ||
139 | return 0; | ||
140 | } | ||
141 | |||
142 | /* | ||
143 | * /dev/watchdog handling | ||
144 | */ | ||
145 | |||
146 | static int softdog_open(struct inode *inode, struct file *file) | ||
147 | { | ||
148 | if (test_and_set_bit(0, &driver_open)) | ||
149 | return -EBUSY; | ||
150 | if (!test_and_clear_bit(0, &orphan_timer)) | ||
151 | __module_get(THIS_MODULE); | ||
152 | /* | ||
153 | * Activate timer | ||
154 | */ | ||
155 | softdog_keepalive(); | ||
156 | return nonseekable_open(inode, file); | ||
157 | } | ||
158 | |||
159 | static int softdog_release(struct inode *inode, struct file *file) | ||
160 | { | 120 | { |
161 | /* | 121 | w->timeout = t; |
162 | * Shut off the timer. | ||
163 | * Lock it in if it's a module and we set nowayout | ||
164 | */ | ||
165 | if (expect_close == 42) { | ||
166 | softdog_stop(); | ||
167 | module_put(THIS_MODULE); | ||
168 | } else { | ||
169 | printk(KERN_CRIT PFX | ||
170 | "Unexpected close, not stopping watchdog!\n"); | ||
171 | set_bit(0, &orphan_timer); | ||
172 | softdog_keepalive(); | ||
173 | } | ||
174 | clear_bit(0, &driver_open); | ||
175 | expect_close = 0; | ||
176 | return 0; | 122 | return 0; |
177 | } | 123 | } |
178 | 124 | ||
179 | static ssize_t softdog_write(struct file *file, const char __user *data, | ||
180 | size_t len, loff_t *ppos) | ||
181 | { | ||
182 | /* | ||
183 | * Refresh the timer. | ||
184 | */ | ||
185 | if (len) { | ||
186 | if (!nowayout) { | ||
187 | size_t i; | ||
188 | |||
189 | /* In case it was set long ago */ | ||
190 | expect_close = 0; | ||
191 | |||
192 | for (i = 0; i != len; i++) { | ||
193 | char c; | ||
194 | |||
195 | if (get_user(c, data + i)) | ||
196 | return -EFAULT; | ||
197 | if (c == 'V') | ||
198 | expect_close = 42; | ||
199 | } | ||
200 | } | ||
201 | softdog_keepalive(); | ||
202 | } | ||
203 | return len; | ||
204 | } | ||
205 | |||
206 | static long softdog_ioctl(struct file *file, unsigned int cmd, | ||
207 | unsigned long arg) | ||
208 | { | ||
209 | void __user *argp = (void __user *)arg; | ||
210 | int __user *p = argp; | ||
211 | int new_margin; | ||
212 | static const struct watchdog_info ident = { | ||
213 | .options = WDIOF_SETTIMEOUT | | ||
214 | WDIOF_KEEPALIVEPING | | ||
215 | WDIOF_MAGICCLOSE, | ||
216 | .firmware_version = 0, | ||
217 | .identity = "Software Watchdog", | ||
218 | }; | ||
219 | switch (cmd) { | ||
220 | case WDIOC_GETSUPPORT: | ||
221 | return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0; | ||
222 | case WDIOC_GETSTATUS: | ||
223 | case WDIOC_GETBOOTSTATUS: | ||
224 | return put_user(0, p); | ||
225 | case WDIOC_KEEPALIVE: | ||
226 | softdog_keepalive(); | ||
227 | return 0; | ||
228 | case WDIOC_SETTIMEOUT: | ||
229 | if (get_user(new_margin, p)) | ||
230 | return -EFAULT; | ||
231 | if (softdog_set_heartbeat(new_margin)) | ||
232 | return -EINVAL; | ||
233 | softdog_keepalive(); | ||
234 | /* Fall */ | ||
235 | case WDIOC_GETTIMEOUT: | ||
236 | return put_user(soft_margin, p); | ||
237 | default: | ||
238 | return -ENOTTY; | ||
239 | } | ||
240 | } | ||
241 | |||
242 | /* | 125 | /* |
243 | * Notifier for system down | 126 | * Notifier for system down |
244 | */ | 127 | */ |
@@ -248,7 +131,7 @@ static int softdog_notify_sys(struct notifier_block *this, unsigned long code, | |||
248 | { | 131 | { |
249 | if (code == SYS_DOWN || code == SYS_HALT) | 132 | if (code == SYS_DOWN || code == SYS_HALT) |
250 | /* Turn the WDT off */ | 133 | /* Turn the WDT off */ |
251 | softdog_stop(); | 134 | softdog_stop(NULL); |
252 | return NOTIFY_DONE; | 135 | return NOTIFY_DONE; |
253 | } | 136 | } |
254 | 137 | ||
@@ -256,28 +139,29 @@ static int softdog_notify_sys(struct notifier_block *this, unsigned long code, | |||
256 | * Kernel Interfaces | 139 | * Kernel Interfaces |
257 | */ | 140 | */ |
258 | 141 | ||
259 | static const struct file_operations softdog_fops = { | 142 | static struct notifier_block softdog_notifier = { |
260 | .owner = THIS_MODULE, | 143 | .notifier_call = softdog_notify_sys, |
261 | .llseek = no_llseek, | ||
262 | .write = softdog_write, | ||
263 | .unlocked_ioctl = softdog_ioctl, | ||
264 | .open = softdog_open, | ||
265 | .release = softdog_release, | ||
266 | }; | 144 | }; |
267 | 145 | ||
268 | static struct miscdevice softdog_miscdev = { | 146 | static struct watchdog_info softdog_info = { |
269 | .minor = WATCHDOG_MINOR, | 147 | .identity = "Software Watchdog", |
270 | .name = "watchdog", | 148 | .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, |
271 | .fops = &softdog_fops, | ||
272 | }; | 149 | }; |
273 | 150 | ||
274 | static struct notifier_block softdog_notifier = { | 151 | static struct watchdog_ops softdog_ops = { |
275 | .notifier_call = softdog_notify_sys, | 152 | .owner = THIS_MODULE, |
153 | .start = softdog_ping, | ||
154 | .stop = softdog_stop, | ||
155 | .ping = softdog_ping, | ||
156 | .set_timeout = softdog_set_timeout, | ||
276 | }; | 157 | }; |
277 | 158 | ||
278 | static char banner[] __initdata = KERN_INFO "Software Watchdog Timer: 0.07 " | 159 | static struct watchdog_device softdog_dev = { |
279 | "initialized. soft_noboot=%d soft_margin=%d sec soft_panic=%d " | 160 | .info = &softdog_info, |
280 | "(nowayout= %d)\n"; | 161 | .ops = &softdog_ops, |
162 | .min_timeout = 1, | ||
163 | .max_timeout = 0xFFFF | ||
164 | }; | ||
281 | 165 | ||
282 | static int __init watchdog_init(void) | 166 | static int __init watchdog_init(void) |
283 | { | 167 | { |
@@ -285,37 +169,36 @@ static int __init watchdog_init(void) | |||
285 | 169 | ||
286 | /* Check that the soft_margin value is within it's range; | 170 | /* Check that the soft_margin value is within it's range; |
287 | if not reset to the default */ | 171 | if not reset to the default */ |
288 | if (softdog_set_heartbeat(soft_margin)) { | 172 | if (soft_margin < 1 || soft_margin > 65535) { |
289 | softdog_set_heartbeat(TIMER_MARGIN); | 173 | pr_info("soft_margin must be 0 < soft_margin < 65536, using %d\n", |
290 | printk(KERN_INFO PFX | ||
291 | "soft_margin must be 0 < soft_margin < 65536, using %d\n", | ||
292 | TIMER_MARGIN); | 174 | TIMER_MARGIN); |
175 | return -EINVAL; | ||
293 | } | 176 | } |
177 | softdog_dev.timeout = soft_margin; | ||
178 | |||
179 | watchdog_set_nowayout(&softdog_dev, nowayout); | ||
294 | 180 | ||
295 | ret = register_reboot_notifier(&softdog_notifier); | 181 | ret = register_reboot_notifier(&softdog_notifier); |
296 | if (ret) { | 182 | if (ret) { |
297 | printk(KERN_ERR PFX | 183 | pr_err("cannot register reboot notifier (err=%d)\n", ret); |
298 | "cannot register reboot notifier (err=%d)\n", ret); | ||
299 | return ret; | 184 | return ret; |
300 | } | 185 | } |
301 | 186 | ||
302 | ret = misc_register(&softdog_miscdev); | 187 | ret = watchdog_register_device(&softdog_dev); |
303 | if (ret) { | 188 | if (ret) { |
304 | printk(KERN_ERR PFX | ||
305 | "cannot register miscdev on minor=%d (err=%d)\n", | ||
306 | WATCHDOG_MINOR, ret); | ||
307 | unregister_reboot_notifier(&softdog_notifier); | 189 | unregister_reboot_notifier(&softdog_notifier); |
308 | return ret; | 190 | return ret; |
309 | } | 191 | } |
310 | 192 | ||
311 | printk(banner, soft_noboot, soft_margin, soft_panic, nowayout); | 193 | pr_info("Software Watchdog Timer: 0.08 initialized. soft_noboot=%d soft_margin=%d sec soft_panic=%d (nowayout=%d)\n", |
194 | soft_noboot, soft_margin, soft_panic, nowayout); | ||
312 | 195 | ||
313 | return 0; | 196 | return 0; |
314 | } | 197 | } |
315 | 198 | ||
316 | static void __exit watchdog_exit(void) | 199 | static void __exit watchdog_exit(void) |
317 | { | 200 | { |
318 | misc_deregister(&softdog_miscdev); | 201 | watchdog_unregister_device(&softdog_dev); |
319 | unregister_reboot_notifier(&softdog_notifier); | 202 | unregister_reboot_notifier(&softdog_notifier); |
320 | } | 203 | } |
321 | 204 | ||