watchdog: softdog: convert to watchdog core
authorAlan Cox <alan@linux.intel.com>
Tue, 28 Feb 2012 22:48:11 +0000 (22:48 +0000)
committerWim Van Sebroeck <wim@iguana.be>
Tue, 27 Mar 2012 18:07:21 +0000 (20:07 +0200)
Convert softdog.c to the new watchdog API.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
drivers/watchdog/Kconfig
drivers/watchdog/softdog.c

index 8f5c317632866d0f699fcdf96226b1a740d71aec..af7444188f5cb5346e9fdc2be4e7a7056edb7fcc 100644 (file)
@@ -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
index da8620f829b28e4430a596927c3ff624b8902a10..fe83beb8f1b7c3f5a0c6b679f209145df77e644f 100644 (file)
@@ -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.
 #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)
+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);
 }