__PHYSICAL_MASK_SHIFT 12 arch/x86/include/asm/page_types.h #define __PHYSICAL_MASK ((phys_addr_t)((1ULL << __PHYSICAL_MASK_SHIFT) - 1)) __PHYSICAL_MASK_SHIFT 139 arch/x86/include/asm/pgtable_64.h #define PTE_FILE_MAX_BITS __PHYSICAL_MASK_SHIFT