ptr_unpack_bits
syncobj = ptr_unpack_bits(fences[n], &flags, 2);
syncobj = ptr_unpack_bits(fences[n], &flags, 2);
#define page_unpack_bits(ptr, bits) ptr_unpack_bits(ptr, bits, PAGE_SHIFT)
#define port_unpack(p, count) ptr_unpack_bits((p)->request_count, count, EXECLIST_COUNT_BITS)