drivers/base/power: add dpm_sysfs_change_owner()

Add a helper to change the owner of a device's power entries. This
needs to happen when the ownership of a device is changed, e.g. when
moving network devices between network namespaces.
This function will be used to correctly account for ownership changes,
e.g. when moving network devices between network namespaces.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 988f34ce2eb04d91209240709a75bf4d7a8183e1..fb8b7990f6fd7b855e7f7b89ffaf9e7013b4217b 100644 (file)
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -3552,6 +3552,10 @@ int device_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid)
        if (error)
                goto out;
 
+       error = dpm_sysfs_change_owner(dev, kuid, kgid);
+       if (error)
+               goto out;
+
 #ifdef CONFIG_BLOCK
        if (sysfs_deprecated && dev->class == &block_class)
                goto out;

diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h
index 444f5c169a0b9211fec64d3e044e2373b443fb31..54292cdd7808bda4d14280c271b37f943c8d21c2 100644 (file)
--- a/drivers/base/power/power.h
+++ b/drivers/base/power/power.h
@@ -74,6 +74,7 @@ extern int pm_qos_sysfs_add_flags(struct device *dev);
 extern void pm_qos_sysfs_remove_flags(struct device *dev);
 extern int pm_qos_sysfs_add_latency_tolerance(struct device *dev);
 extern void pm_qos_sysfs_remove_latency_tolerance(struct device *dev);
+extern int dpm_sysfs_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid);
 
 #else /* CONFIG_PM */
 
@@ -88,6 +89,8 @@ static inline void pm_runtime_remove(struct device *dev) {}
 
 static inline int dpm_sysfs_add(struct device *dev) { return 0; }
 static inline void dpm_sysfs_remove(struct device *dev) {}
+static inline int dpm_sysfs_change_owner(struct device *dev, kuid_t kuid,
+                                        kgid_t kgid) { return 0; }
 
 #endif
 

diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c
index d7d82db2e4bc401fb5a35c8eaa11090aa39ce01a..2b99fe1eb207dabd9737b28f11686ff514f942f6 100644 (file)
--- a/drivers/base/power/sysfs.c
+++ b/drivers/base/power/sysfs.c
@@ -480,6 +480,14 @@ static ssize_t wakeup_last_time_ms_show(struct device *dev,
        return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
 }
 
+static inline int dpm_sysfs_wakeup_change_owner(struct device *dev, kuid_t kuid,
+                                               kgid_t kgid)
+{
+       if (dev->power.wakeup && dev->power.wakeup->dev)
+               return device_change_owner(dev->power.wakeup->dev, kuid, kgid);
+       return 0;
+}
+
 static DEVICE_ATTR_RO(wakeup_last_time_ms);
 
 #ifdef CONFIG_PM_AUTOSLEEP
@@ -501,7 +509,13 @@ static ssize_t wakeup_prevent_sleep_time_ms_show(struct device *dev,
 
 static DEVICE_ATTR_RO(wakeup_prevent_sleep_time_ms);
 #endif /* CONFIG_PM_AUTOSLEEP */
-#endif /* CONFIG_PM_SLEEP */
+#else /* CONFIG_PM_SLEEP */
+static inline int dpm_sysfs_wakeup_change_owner(struct device *dev, kuid_t kuid,
+                                               kgid_t kgid)
+{
+       return 0;
+}
+#endif
 
 #ifdef CONFIG_PM_ADVANCED_DEBUG
 static ssize_t runtime_usage_show(struct device *dev,
@@ -684,6 +698,45 @@ int dpm_sysfs_add(struct device *dev)
        return rc;
 }
 
+int dpm_sysfs_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid)
+{
+       int rc;
+
+       if (device_pm_not_required(dev))
+               return 0;
+
+       rc = sysfs_group_change_owner(&dev->kobj, &pm_attr_group, kuid, kgid);
+       if (rc)
+               return rc;
+
+       if (pm_runtime_callbacks_present(dev)) {
+               rc = sysfs_group_change_owner(
+                       &dev->kobj, &pm_runtime_attr_group, kuid, kgid);
+               if (rc)
+                       return rc;
+       }
+
+       if (device_can_wakeup(dev)) {
+               rc = sysfs_group_change_owner(&dev->kobj, &pm_wakeup_attr_group,
+                                             kuid, kgid);
+               if (rc)
+                       return rc;
+
+               rc = dpm_sysfs_wakeup_change_owner(dev, kuid, kgid);
+               if (rc)
+                       return rc;
+       }
+
+       if (dev->power.set_latency_tolerance) {
+               rc = sysfs_group_change_owner(
+                       &dev->kobj, &pm_qos_latency_tolerance_attr_group, kuid,
+                       kgid);
+               if (rc)
+                       return rc;
+       }
+       return 0;
+}
+
 int wakeup_sysfs_add(struct device *dev)
 {
        return sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);