s390/vmlogrdr: cleanup driver attribute usage

Let the driver core handle driver attribute creation and removal. This
will simplify the code and eliminates races between attribute
availability and userspace notification via uevents.

Signed-off-by: Sebastian Ott <[e-mail]>
Signed-off-by: Martin Schwidefsky <[e-mail]>

drivers/s390/char/vmlogrdr.c

···
 	len = strlen(buf);
 	return len;
 }
-
-
 static DRIVER_ATTR(recording_status, 0444, vmlogrdr_recording_status_show,
 		   NULL);
+static struct attribute *vmlogrdr_drv_attrs[] = {
+	&driver_attr_recording_status.attr,
+	NULL,
+};
+static struct attribute_group vmlogrdr_drv_attr_group = {
+	.attrs = vmlogrdr_drv_attrs,
+};
+static const struct attribute_group *vmlogrdr_drv_attr_groups[] = {
+	&vmlogrdr_drv_attr_group,
+	NULL,
+};
 
 static struct attribute *vmlogrdr_attrs[] = {
 	&dev_attr_autopurge.attr,
···
 	.name = "vmlogrdr",
 	.bus  = &iucv_bus,
 	.pm = &vmlogrdr_pm_ops,
+	.groups = vmlogrdr_drv_attr_groups,
 };
-
 
 static int vmlogrdr_register_driver(void)
 {
···
 	if (ret)
 		goto out_iucv;
 
-	ret = driver_create_file(&vmlogrdr_driver,
-				 &driver_attr_recording_status);
-	if (ret)
-		goto out_driver;
-
 	vmlogrdr_class = class_create(THIS_MODULE, "vmlogrdr");
 	if (IS_ERR(vmlogrdr_class)) {
 		ret = PTR_ERR(vmlogrdr_class);
 		vmlogrdr_class = NULL;
-		goto out_attr;
+		goto out_driver;
 	}
 	return 0;
 
-out_attr:
-	driver_remove_file(&vmlogrdr_driver, &driver_attr_recording_status);
 out_driver:
 	driver_unregister(&vmlogrdr_driver);
 out_iucv:
···
 {
 	class_destroy(vmlogrdr_class);
 	vmlogrdr_class = NULL;
-	driver_remove_file(&vmlogrdr_driver, &driver_attr_recording_status);
 	driver_unregister(&vmlogrdr_driver);
 	iucv_unregister(&vmlogrdr_iucv_handler, 1);
 }