driver core: Introduce device_move(): move a device to a new parent.

Provide a function device_move() to move a device to a new parent device. Add
auxilliary functions kobject_move() and sysfs_move_dir().
kobject_move() generates a new uevent of type KOBJ_MOVE, containing the
previous path (DEVPATH_OLD) in addition to the usual values. For this, a new
interface kobject_uevent_env() is created that allows to add further
environmental data to the uevent at the kobject layer.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

3 files changed, 17 insertions, 0 deletions

diff --git a/include/linux/device.h b/include/linux/device.h
index 0a0370c7418..583a341e016 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -424,6 +424,7 @@ extern int device_for_each_child(struct device *, void *,
 extern struct device *device_find_child(struct device *, void *data,
 					int (*match)(struct device *, void *));
 extern int device_rename(struct device *dev, char *new_name);
+extern int device_move(struct device *dev, struct device *new_parent);
 
 /*
  * Manual binding of a device to driver. See drivers/base/bus.c
diff --git a/include/linux/kobject.h b/include/linux/kobject.h
index bcd9cd173c2..d1c8d28fa92 100644
--- a/include/linux/kobject.h
+++ b/include/linux/kobject.h
@@ -47,6 +47,7 @@ enum kobject_action {
 	KOBJ_UMOUNT	= (__force kobject_action_t) 0x05,	/* umount event for block devices (broken) */
 	KOBJ_OFFLINE	= (__force kobject_action_t) 0x06,	/* device offline */
 	KOBJ_ONLINE	= (__force kobject_action_t) 0x07,	/* device online */
+	KOBJ_MOVE	= (__force kobject_action_t) 0x08,	/* device move */
 };
 
 struct kobject {
@@ -76,6 +77,7 @@ extern int __must_check kobject_add(struct kobject *);
 extern void kobject_del(struct kobject *);
 
 extern int __must_check kobject_rename(struct kobject *, const char *new_name);
+extern int __must_check kobject_move(struct kobject *, struct kobject *);
 
 extern int __must_check kobject_register(struct kobject *);
 extern void kobject_unregister(struct kobject *);
@@ -264,6 +266,8 @@ extern int __must_check subsys_create_file(struct subsystem * ,
 
 #if defined(CONFIG_HOTPLUG)
 void kobject_uevent(struct kobject *kobj, enum kobject_action action);
+void kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
+			char *envp[]);
 
 int add_uevent_var(char **envp, int num_envp, int *cur_index,
 			char *buffer, int buffer_size, int *cur_len,
@@ -271,6 +275,10 @@ int add_uevent_var(char **envp, int num_envp, int *cur_index,
 	__attribute__((format (printf, 7, 8)));
 #else
 static inline void kobject_uevent(struct kobject *kobj, enum kobject_action action) { }
+static inline void kobject_uevent_env(struct kobject *kobj,
+				      enum kobject_action action,
+				      char *envp[])
+{ }
 
 static inline int add_uevent_var(char **envp, int num_envp, int *cur_index,
 				      char *buffer, int buffer_size, int *cur_len, 
diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h
index 6d5c43d31de..2129d1b6c87 100644
--- a/include/linux/sysfs.h
+++ b/include/linux/sysfs.h
@@ -97,6 +97,9 @@ extern int __must_check
 sysfs_rename_dir(struct kobject *, const char *new_name);
 
 extern int __must_check
+sysfs_move_dir(struct kobject *, struct kobject *);
+
+extern int __must_check
 sysfs_create_file(struct kobject *, const struct attribute *);
 
 extern int __must_check
@@ -142,6 +145,11 @@ static inline int sysfs_rename_dir(struct kobject * k, const char *new_name)
 	return 0;
 }
 
+static inline int sysfs_move_dir(struct kobject * k, struct kobject * new_parent)
+{
+	return 0;
+}
+
 static inline int sysfs_create_file(struct kobject * k, const struct attribute * a)
 {
 	return 0;