FIRST_OBJ_PAGE_TYPE_MASK
return zpdesc->first_obj_offset & FIRST_OBJ_PAGE_TYPE_MASK;
VM_WARN_ON_ONCE(offset & ~FIRST_OBJ_PAGE_TYPE_MASK);
zpdesc->first_obj_offset &= ~FIRST_OBJ_PAGE_TYPE_MASK;
zpdesc->first_obj_offset |= offset & FIRST_OBJ_PAGE_TYPE_MASK;