kset: convert struct bus_device->devices to use kset_create

Dynamically create the kset instead of declaring it statically.

Having 3 static kobjects in one structure is not only foolish, but ripe
for nasty race conditions if handled improperly.  We also rename the
field to catch any potential users of it (not that there should be
outside of the driver core...)

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/base/bus.c

@@ -449,7 +449,7 @@ int bus_add_device(struct device * dev)
 		error = device_add_attrs(bus, dev);
 		if (error)
 			goto out_put;
-		error = sysfs_create_link(&bus->devices.kobj,
+		error = sysfs_create_link(&bus->devices_kset->kobj,
 						&dev->kobj, dev->bus_id);
 		if (error)
 			goto out_id;
@@ -466,7 +466,7 @@ int bus_add_device(struct device * dev)
 out_deprecated:
 	sysfs_remove_link(&dev->kobj, "subsystem");
 out_subsys:
-	sysfs_remove_link(&bus->devices.kobj, dev->bus_id);
+	sysfs_remove_link(&bus->devices_kset->kobj, dev->bus_id);
 out_id:
 	device_remove_attrs(bus, dev);
 out_put:
@@ -512,7 +512,7 @@ void bus_remove_device(struct device * dev)
 	if (dev->bus) {
 		sysfs_remove_link(&dev->kobj, "subsystem");
 		remove_deprecated_bus_links(dev);
-		sysfs_remove_link(&dev->bus->devices.kobj, dev->bus_id);
+		sysfs_remove_link(&dev->bus->devices_kset->kobj, dev->bus_id);
 		device_remove_attrs(dev->bus, dev);
 		if (dev->is_registered) {
 			dev->is_registered = 0;
@@ -862,11 +862,12 @@ int bus_register(struct bus_type * bus)
 	if (retval)
 		goto bus_uevent_fail;
 
-	kobject_set_name(&bus->devices.kobj, "devices");
-	bus->devices.kobj.parent = &bus->subsys.kobj;
-	retval = kset_register(&bus->devices);
-	if (retval)
+	bus->devices_kset = kset_create_and_add("devices", NULL,
+						&bus->subsys.kobj);
+	if (!bus->devices_kset) {
+		retval = -ENOMEM;
 		goto bus_devices_fail;
+	}
 
 	kobject_set_name(&bus->drivers.kobj, "drivers");
 	bus->drivers.kobj.parent = &bus->subsys.kobj;
@@ -894,7 +895,7 @@ int bus_register(struct bus_type * bus)
 bus_probe_files_fail:
 	kset_unregister(&bus->drivers);
 bus_drivers_fail:
-	kset_unregister(&bus->devices);
+	kset_unregister(bus->devices_kset);
 bus_devices_fail:
 	bus_remove_file(bus, &bus_attr_uevent);
 bus_uevent_fail:
@@ -916,7 +917,7 @@ void bus_unregister(struct bus_type * bus)
 	bus_remove_attrs(bus);
 	remove_probe_files(bus);
 	kset_unregister(&bus->drivers);
-	kset_unregister(&bus->devices);
+	kset_unregister(bus->devices_kset);
 	bus_remove_file(bus, &bus_attr_uevent);
 	subsystem_unregister(&bus->subsys);
 }

include/linux/device.h

@@ -55,7 +55,7 @@ struct bus_type {
 
 	struct kset		subsys;
 	struct kset		drivers;
-	struct kset		devices;
+	struct kset		*devices_kset;
 	struct klist		klist_devices;
 	struct klist		klist_drivers;