Bitfields for VDS flags: Bit(s) Description ) 0 reserved (zero) 1 data should be copied into buffer (ignored if 2 set) 2 buffer should not be allocated if region noncontiguous or crosses physical alignment boundary specified by 4-5 3 don't attempt automatic remap 4 region must not cross 64K physical alignment boundary 5 region must not cross 128K physical alignment boundary 6-15 reserved (zero)