PMD_MASK           12 arch/x86/include/asm/pgtable_32_types.h # define PMD_MASK	(~(PMD_SIZE - 1))
PMD_MASK           50 arch/x86/include/asm/pgtable_64_types.h #define PMD_MASK	(~(PMD_SIZE - 1))
PMD_MASK           22 include/asm-generic/pgtable-nopmd.h #define PMD_MASK  	(~(PMD_SIZE-1))