HAMMER_BLOCKMAP_LAYER2_INDEX
HAMMER_BLOCKMAP_LAYER2_INDEX(zone_offset),
i = HAMMER_BLOCKMAP_LAYER2_INDEX(offset);
HAMMER_BLOCKMAP_LAYER2_INDEX(offset),
HAMMER_BLOCKMAP_LAYER2_INDEX(offset),
j = HAMMER_BLOCKMAP_LAYER2_INDEX(offset);
(HAMMER_BLOCKMAP_LAYER2_INDEX(zone2_offset) * \