watchdog: softdog: convert to watchdog core (a5132caf) · Commits · jan.koester / Linux

drivers/watchdog/Kconfig

+1 −0

Original line number	Diff line number	Diff line
		@@ -55,6 +55,7 @@ comment "Watchdog Device Drivers"

		config SOFT_WATCHDOG
		tristate "Software watchdog"
		select WATCHDOG_CORE
		help
		A software monitoring watchdog. This will fail to reboot your system
		from some situations that the hardware watchdog will recover

drivers/watchdog/softdog.c

+36 −146

Original line number	Diff line number	Diff line
		/*
		* SoftDog 0.07: A Software Watchdog Device
		* SoftDog: A Software Watchdog Device
		*
		* (c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>,
		* All Rights Reserved.
		@@ -44,17 +44,15 @@
		#include <linux/timer.h>
		#include <linux/miscdevice.h>
		#include <linux/watchdog.h>
		#include <linux/fs.h>
		#include <linux/notifier.h>
		#include <linux/reboot.h>
		#include <linux/init.h>
		#include <linux/jiffies.h>
		#include <linux/uaccess.h>
		#include <linux/kernel.h>

		#define TIMER_MARGIN 60 /* Default is 60 seconds */
		static int soft_margin = TIMER_MARGIN; /* in seconds */
		module_param(soft_margin, int, 0);
		static unsigned int soft_margin = TIMER_MARGIN; /* in seconds */
		module_param(soft_margin, uint, 0);
		MODULE_PARM_DESC(soft_margin,
		"Watchdog soft_margin in seconds. (0 < soft_margin < 65536, default="
		__MODULE_STRING(TIMER_MARGIN) ")");
		@@ -65,16 +63,10 @@ MODULE_PARM_DESC(nowayout,
		"Watchdog cannot be stopped once started (default="
		__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");

		#ifdef ONLY_TESTING
		static int soft_noboot = 1;
		#else
		static int soft_noboot = 0;
		#endif /* ONLY_TESTING */

		module_param(soft_noboot, int, 0);
		MODULE_PARM_DESC(soft_noboot,
		"Softdog action, set to 1 to ignore reboots, 0 to reboot "
		"(default depends on ONLY_TESTING)");
		"Softdog action, set to 1 to ignore reboots, 0 to reboot (default=0)");

		static int soft_panic;
		module_param(soft_panic, int, 0);
		@@ -89,9 +81,6 @@ static void watchdog_fire(unsigned long);

		static struct timer_list watchdog_ticktock =
		TIMER_INITIALIZER(watchdog_fire, 0, 0);
		static unsigned long driver_open, orphan_timer;
		static char expect_close;


		/*
		* If the timer expires..
		@@ -99,9 +88,6 @@ static char expect_close;

		static void watchdog_fire(unsigned long data)
		{
		if (test_and_clear_bit(0, &orphan_timer))
		module_put(THIS_MODULE);

		if (soft_noboot)
		pr_crit("Triggered - Reboot ignored\n");
		else if (soft_panic) {
		@@ -118,126 +104,24 @@ static void watchdog_fire(unsigned long data)
		* Softdog operations
		*/

		static int softdog_keepalive(void)
		static int softdog_ping(struct watchdog_device *w)
		{
		mod_timer(&watchdog_ticktock, jiffies+(soft_margin*HZ));
		mod_timer(&watchdog_ticktock, jiffies+(w->timeout*HZ));
		return 0;
		}

		static int softdog_stop(void)
		static int softdog_stop(struct watchdog_device *w)
		{
		del_timer(&watchdog_ticktock);
		return 0;
		}

		static int softdog_set_heartbeat(int t)
		{
		if ((t < 0x0001) \|\| (t > 0xFFFF))
		return -EINVAL;

		soft_margin = t;
		return 0;
		}

		/*
		* /dev/watchdog handling
		*/

		static int softdog_open(struct inode inode, struct file file)
		{
		if (test_and_set_bit(0, &driver_open))
		return -EBUSY;
		if (!test_and_clear_bit(0, &orphan_timer))
		__module_get(THIS_MODULE);
		/*
		* Activate timer
		*/
		softdog_keepalive();
		return nonseekable_open(inode, file);
		}

		static int softdog_release(struct inode inode, struct file file)
		static int softdog_set_timeout(struct watchdog_device *w, unsigned int t)
		{
		/*
		* Shut off the timer.
		* Lock it in if it's a module and we set nowayout
		*/
		if (expect_close == 42) {
		softdog_stop();
		module_put(THIS_MODULE);
		} else {
		pr_crit("Unexpected close, not stopping watchdog!\n");
		set_bit(0, &orphan_timer);
		softdog_keepalive();
		}
		clear_bit(0, &driver_open);
		expect_close = 0;
		w->timeout = t;
		return 0;
		}

		static ssize_t softdog_write(struct file file, const char __user data,
		size_t len, loff_t *ppos)
		{
		/*
		* Refresh the timer.
		*/
		if (len) {
		if (!nowayout) {
		size_t i;

		/* In case it was set long ago */
		expect_close = 0;

		for (i = 0; i != len; i++) {
		char c;

		if (get_user(c, data + i))
		return -EFAULT;
		if (c == 'V')
		expect_close = 42;
		}
		}
		softdog_keepalive();
		}
		return len;
		}

		static long softdog_ioctl(struct file *file, unsigned int cmd,
		unsigned long arg)
		{
		void __user argp = (void __user )arg;
		int __user *p = argp;
		int new_margin;
		static const struct watchdog_info ident = {
		.options = WDIOF_SETTIMEOUT \|
		WDIOF_KEEPALIVEPING \|
		WDIOF_MAGICCLOSE,
		.firmware_version = 0,
		.identity = "Software Watchdog",
		};
		switch (cmd) {
		case WDIOC_GETSUPPORT:
		return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
		case WDIOC_GETSTATUS:
		case WDIOC_GETBOOTSTATUS:
		return put_user(0, p);
		case WDIOC_KEEPALIVE:
		softdog_keepalive();
		return 0;
		case WDIOC_SETTIMEOUT:
		if (get_user(new_margin, p))
		return -EFAULT;
		if (softdog_set_heartbeat(new_margin))
		return -EINVAL;
		softdog_keepalive();
		/* Fall */
		case WDIOC_GETTIMEOUT:
		return put_user(soft_margin, p);
		default:
		return -ENOTTY;
		}
		}

		/*
		* Notifier for system down
		*/
		@@ -247,7 +131,7 @@ static int softdog_notify_sys(struct notifier_block *this, unsigned long code,
		{
		if (code == SYS_DOWN \|\| code == SYS_HALT)
		/* Turn the WDT off */
		softdog_stop();
		softdog_stop(NULL);
		return NOTIFY_DONE;
		}

		@@ -255,23 +139,28 @@ static int softdog_notify_sys(struct notifier_block *this, unsigned long code,
		* Kernel Interfaces
		*/

		static const struct file_operations softdog_fops = {
		.owner = THIS_MODULE,
		.llseek = no_llseek,
		.write = softdog_write,
		.unlocked_ioctl = softdog_ioctl,
		.open = softdog_open,
		.release = softdog_release,
		static struct notifier_block softdog_notifier = {
		.notifier_call = softdog_notify_sys,
		};

		static struct miscdevice softdog_miscdev = {
		.minor = WATCHDOG_MINOR,
		.name = "watchdog",
		.fops = &softdog_fops,
		static struct watchdog_info softdog_info = {
		.identity = "Software Watchdog",
		.options = WDIOF_SETTIMEOUT \| WDIOF_KEEPALIVEPING \| WDIOF_MAGICCLOSE,
		};

		static struct notifier_block softdog_notifier = {
		.notifier_call = softdog_notify_sys,
		static struct watchdog_ops softdog_ops = {
		.owner = THIS_MODULE,
		.start = softdog_ping,
		.stop = softdog_stop,
		.ping = softdog_ping,
		.set_timeout = softdog_set_timeout,
		};

		static struct watchdog_device softdog_dev = {
		.info = &softdog_info,
		.ops = &softdog_ops,
		.min_timeout = 1,
		.max_timeout = 0xFFFF
		};

		static int __init watchdog_init(void)
		@@ -280,11 +169,14 @@ static int __init watchdog_init(void)

		/* Check that the soft_margin value is within it's range;
		if not reset to the default */
		if (softdog_set_heartbeat(soft_margin)) {
		softdog_set_heartbeat(TIMER_MARGIN);
		if (soft_margin < 1 \|\| soft_margin > 65535) {
		pr_info("soft_margin must be 0 < soft_margin < 65536, using %d\n",
		TIMER_MARGIN);
		return -EINVAL;
		}
		softdog_dev.timeout = soft_margin;

		watchdog_set_nowayout(&softdog_dev, nowayout);

		ret = register_reboot_notifier(&softdog_notifier);
		if (ret) {
		@@ -292,15 +184,13 @@ static int __init watchdog_init(void)
		return ret;
		}

		ret = misc_register(&softdog_miscdev);
		ret = watchdog_register_device(&softdog_dev);
		if (ret) {
		pr_err("cannot register miscdev on minor=%d (err=%d)\n",
		WATCHDOG_MINOR, ret);
		unregister_reboot_notifier(&softdog_notifier);
		return ret;
		}

		pr_info("Software Watchdog Timer: 0.07 initialized. soft_noboot=%d soft_margin=%d sec soft_panic=%d (nowayout= %d)\n",
		pr_info("Software Watchdog Timer: 0.08 initialized. soft_noboot=%d soft_margin=%d sec soft_panic=%d (nowayout=%d)\n",
		soft_noboot, soft_margin, soft_panic, nowayout);

		return 0;
		@@ -308,7 +198,7 @@ static int __init watchdog_init(void)

		static void __exit watchdog_exit(void)
		{
		misc_deregister(&softdog_miscdev);
		watchdog_unregister_device(&softdog_dev);
		unregister_reboot_notifier(&softdog_notifier);
		}