ovl_path_is_whiteout
positive = !ovl_path_is_whiteout(OVL_FS(dentry->d_sb), &path);
if (ovl_path_is_whiteout(ofs, &path)) {
bool ovl_path_is_whiteout(struct ovl_fs *ofs, const struct path *path);
return ovl_path_is_whiteout(ofs, &upperpath);