Use kobj_to_dev() instead of container_of() Signed-off-by: Tian Tao <tiantao6@hisilicon.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>