MCX_SQ_SEGS_PER_SLOT
1 + ((MCX_SQ_ENTRY_MAX_SLOTS-1) * MCX_SQ_SEGS_PER_SLOT)
slots += (map->dm_nsegs+2) / MCX_SQ_SEGS_PER_SLOT;
nseg = MCX_SQ_SEGS_PER_SLOT;