bvec_iter_advance
bvec_iter_advance(bip->bip_vec, &bip->bip_iter, bytes);
bvec_iter_advance(bvecs, iter, bv.bv_len);
bvec_iter_advance(bvec, iter, bv.bv_len);
bvec_iter_advance(bio->bi_io_vec, &iter, this_step);
bvec_iter_advance(bip->bip_vec, &bip->bip_iter, tag_now);
bvec_iter_advance((struct bio_vec *)dp->context_ptr,
if (!bvec_iter_advance(bip->bip_vec, &bip->bip_iter, cur_len))
bvec_iter_advance(bio->bi_io_vec, iter, bytes);
bvec_iter_advance((it)->bvecs, &(it)->iter, (n)); \
bvec_iter_advance(src_bvec, &bi, offset);
bvec_iter_advance(bvecs, &cursor->bvec_iter, bytes);
bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);