watchdog: Drop pointer to watchdog device from struct watchdog_device

The lifetime of the watchdog device pointer is different from the lifetime
of its character device. Remove it entirely to avoid race conditions.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

diff --git a/Documentation/watchdog/watchdog-kernel-api.txt b/Documentation/watchdog/watchdog-kernel-api.txt
index 312f60009c3e022f95e18a1b918b0d298d08fb15..55120a055a14d57f98053cb7147b25ad4c2a6214 100644 (file)
--- a/Documentation/watchdog/watchdog-kernel-api.txt
+++ b/Documentation/watchdog/watchdog-kernel-api.txt
@@ -44,7 +44,6 @@ The watchdog device structure looks like this:
 
 struct watchdog_device {
        int id;
-       struct device *dev;
        struct device *parent;
        const struct attribute_group **groups;
        const struct watchdog_info *info;
@@ -66,7 +65,6 @@ It contains following fields:
   /dev/watchdog0 cdev (dynamic major, minor 0) as well as the old
   /dev/watchdog miscdev. The id is set automatically when calling
   watchdog_register_device.
-* dev: device under the watchdog class (created by watchdog_register_device).
 * parent: set this to the parent device (or NULL) before calling
   watchdog_register_device.
 * groups: List of sysfs attribute groups to create when creating the watchdog

diff --git a/drivers/watchdog/watchdog_core.c b/drivers/watchdog/watchdog_core.c
index ec1ab6c1a80bfb2cfc3686c653d8b52d1e9a1f7a..e600fd93b7de50f359f68a6007275ef0a6530a09 100644 (file)
--- a/drivers/watchdog/watchdog_core.c
+++ b/drivers/watchdog/watchdog_core.c
@@ -249,8 +249,8 @@ static int __watchdog_register_device(struct watchdog_device *wdd)
 
                ret = register_reboot_notifier(&wdd->reboot_nb);
                if (ret) {
-                       dev_err(wdd->dev, "Cannot register reboot notifier (%d)\n",
-                               ret);
+                       pr_err("watchdog%d: Cannot register reboot notifier (%d)\n",
+                              wdd->id, ret);
                        watchdog_dev_unregister(wdd);
                        ida_simple_remove(&watchdog_ida, wdd->id);
                        return ret;
@@ -262,8 +262,8 @@ static int __watchdog_register_device(struct watchdog_device *wdd)
 
                ret = register_restart_handler(&wdd->restart_nb);
                if (ret)
-                       dev_warn(wdd->dev, "Cannot register restart handler (%d)\n",
-                                ret);
+                       pr_warn("watchog%d: Cannot register restart handler (%d)\n",
+                               wdd->id, ret);
        }
 
        return 0;

diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index e89ccb2e9603b7d8a19ff855d6ad96c902506cf5..ba2ecce4aae685df4ce30a8263fec56f3e0b729d 100644 (file)
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -143,7 +143,8 @@ static int watchdog_stop(struct watchdog_device *wdd)
                return 0;
 
        if (test_bit(WDOG_NO_WAY_OUT, &wdd->status)) {
-               dev_info(wdd->dev, "nowayout prevents watchdog being stopped!\n");
+               pr_info("watchdog%d: nowayout prevents watchdog being stopped!\n",
+                       wdd->id);
                return -EBUSY;
        }
 
@@ -604,7 +605,7 @@ static int watchdog_release(struct inode *inode, struct file *file)
 
        /* If the watchdog was not stopped, send a keepalive ping */
        if (err < 0) {
-               dev_crit(wdd->dev, "watchdog did not stop!\n");
+               pr_crit("watchdog%d: watchdog did not stop!\n", wdd->id);
                watchdog_ping(wdd);
        }
 
@@ -751,7 +752,6 @@ int watchdog_dev_register(struct watchdog_device *wdd)
                watchdog_cdev_unregister(wdd);
                return PTR_ERR(dev);
        }
-       wdd->dev = dev;
 
        return ret;
 }
@@ -766,8 +766,7 @@ int watchdog_dev_register(struct watchdog_device *wdd)
 
 void watchdog_dev_unregister(struct watchdog_device *wdd)
 {
-       device_destroy(&watchdog_class, wdd->dev->devt);
-       wdd->dev = NULL;
+       device_destroy(&watchdog_class, wdd->wd_data->cdev.dev);
        watchdog_cdev_unregister(wdd);
 }
 

diff --git a/include/linux/watchdog.h b/include/linux/watchdog.h
index 076df50ea0da158dce79d4e4463d4fd5cafcb418..b585fa2507eea4fd841b6cd27c4919e137e0a8ee 100644 (file)
--- a/include/linux/watchdog.h
+++ b/include/linux/watchdog.h
@@ -53,7 +53,6 @@ struct watchdog_ops {
 /** struct watchdog_device - The structure that defines a watchdog device
  *
  * @id:                The watchdog's ID. (Allocated by watchdog_register_device)
- * @dev:       The device for our watchdog
  * @parent:    The parent bus device
  * @groups:    List of sysfs attribute groups to create when creating the
  *             watchdog device.
@@ -82,7 +81,6 @@ struct watchdog_ops {
  */
 struct watchdog_device {
        int id;
-       struct device *dev;
        struct device *parent;
        const struct attribute_group **groups;
        const struct watchdog_info *info;