return 0;
struct onenand_chip *this = mtd->priv; int ret;  ret = onenand_block_isbad(mtd, ofs); if (ret) {  if (ret > 0) return 0; return ret; }  return this->block_markbad(mtd, ofs);
static int onenand_block_markbad(struct mtd_info *mtd, loff_t ofs){	/* see above */	return 0;}