diff options
Diffstat (limited to 'drivers/watchdog')
| -rw-r--r-- | drivers/watchdog/Kconfig | 1 | ||||
| -rw-r--r-- | drivers/watchdog/softdog.c | 182 |
2 files changed, 37 insertions, 146 deletions
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 8f5c31763286..af7444188f5c 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -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 diff --git a/drivers/watchdog/softdog.c b/drivers/watchdog/softdog.c index da8620f829b2..fe83beb8f1b7 100644 --- a/drivers/watchdog/softdog.c +++ b/drivers/watchdog/softdog.c @@ -1,5 +1,5 @@ /* - * 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) { @@ -118,127 +104,25 @@ 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) +static int softdog_set_timeout(struct watchdog_device *w, unsigned int t) { - if ((t < 0x0001) || (t > 0xFFFF)) - return -EINVAL; - - soft_margin = t; + w->timeout = 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) -{ - /* - * 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; - 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); } |