phys_gap_bit
rq->phys_gap_bit = bio_seg_gap(rq->q, rq->biotail, bio,
rq->phys_gap_bit);
rq->phys_gap_bit = bio->bi_bvec_gap_bit;
req->phys_gap_bit);
req->phys_gap_bit = bio_seg_gap(req->q, req->biotail, next->bio,
min_not_zero(next->phys_gap_bit,
req->phys_gap_bit));
req->phys_gap_bit = bio_seg_gap(req->q, req->biotail, bio,
req->phys_gap_bit);
req->phys_gap_bit = bio_seg_gap(req->q, bio, req->bio,
rq->phys_gap_bit = bio->bi_bvec_gap_bit;
rq->phys_gap_bit = rq_src->phys_gap_bit;
rq->phys_gap_bit = 0;
rq->phys_gap_bit = 0;
rq->phys_gap_bit = 0;
return ~(((1 << req->phys_gap_bit) >> 1) - 1);