kernfs_find_ns
kn = kernfs_find_ns(parent, dentry->d_name.name, ns);
kn = kernfs_find_ns(parent, name, ns);
if (kernfs_find_ns(new_parent, new_name, new_ns))
parent = kernfs_find_ns(parent, name, ns);
kn = kernfs_find_ns(parent, name, ns);