ublk_req_build_flags
iod->op_flags = ublk_op | ublk_req_build_flags(req);
static inline unsigned int ublk_req_build_flags(struct request *req);
iod->op_flags = ublk_op | ublk_req_build_flags(req);
iod->op_flags = ublk_op | ublk_req_build_flags(req);