REQ_F_INFLIGHT
if (req->flags & REQ_F_INFLIGHT)
REQ_F_INFLIGHT | REQ_F_CREDS | REQ_F_ASYNC_DATA)
if (req->flags & REQ_F_INFLIGHT)
if (!(req->flags & REQ_F_INFLIGHT)) {
req->flags |= REQ_F_INFLIGHT;
if (req->flags & REQ_F_INFLIGHT)