VSCSIIF_SG_GRANT
for (i = 0; i < (shadow->nr_segments & ~VSCSIIF_SG_GRANT); i++)
shadow->nr_segments = VSCSIIF_SG_GRANT | seg_grants;
nr_segments &= ~VSCSIIF_SG_GRANT;
if (ring_req->nr_segments & VSCSIIF_SG_GRANT) {