From 4226ab93d8ae3fd895abe45879fe34d489a98718 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Mon, 26 May 2008 23:30:58 +0100 Subject: [PATCH] x86: use pteval_t for _PAGE_FOO Rather than making _PAGE_* constants signed, and then relying on sign-extension to make sure that masks derived from them are wide enough, just explicitly type them pteval_t. This guarantees that they and any derived values are the right size for the current pte format. The reliance on sign extension is fragile, and invokes some very subtle corners of the C type system. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Thomas Gleixner --- include/asm-x86/pgtable.h | 49 ++++++++++++++++++--------------------- 1 file changed, 22 insertions(+), 27 deletions(-) diff --git a/include/asm-x86/pgtable.h b/include/asm-x86/pgtable.h index 97c271b291..fab3ecb54b 100644 --- a/include/asm-x86/pgtable.h +++ b/include/asm-x86/pgtable.h @@ -20,30 +20,25 @@ #define _PAGE_BIT_PAT_LARGE 12 /* On 2MB or 1GB pages */ #define _PAGE_BIT_NX 63 /* No execute: only valid after cpuid check */ -/* - * Note: we use _AC(1, L) instead of _AC(1, UL) so that we get a - * sign-extended value on 32-bit with all 1's in the upper word, - * which preserves the upper pte values on 64-bit ptes: - */ -#define _PAGE_PRESENT (_AC(1, L)<<_PAGE_BIT_PRESENT) -#define _PAGE_RW (_AC(1, L)<<_PAGE_BIT_RW) -#define _PAGE_USER (_AC(1, L)<<_PAGE_BIT_USER) -#define _PAGE_PWT (_AC(1, L)<<_PAGE_BIT_PWT) -#define _PAGE_PCD (_AC(1, L)<<_PAGE_BIT_PCD) -#define _PAGE_ACCESSED (_AC(1, L)<<_PAGE_BIT_ACCESSED) -#define _PAGE_DIRTY (_AC(1, L)<<_PAGE_BIT_DIRTY) -#define _PAGE_PSE (_AC(1, L)<<_PAGE_BIT_PSE) /* 2MB page */ -#define _PAGE_GLOBAL (_AC(1, L)<<_PAGE_BIT_GLOBAL) /* Global TLB entry */ -#define _PAGE_UNUSED1 (_AC(1, L)<<_PAGE_BIT_UNUSED1) -#define _PAGE_UNUSED2 (_AC(1, L)<<_PAGE_BIT_UNUSED2) -#define _PAGE_UNUSED3 (_AC(1, L)<<_PAGE_BIT_UNUSED3) -#define _PAGE_PAT (_AC(1, L)<<_PAGE_BIT_PAT) -#define _PAGE_PAT_LARGE (_AC(1, L)<<_PAGE_BIT_PAT_LARGE) +#define _PAGE_PRESENT (_AT(pteval_t, 1) << _PAGE_BIT_PRESENT) +#define _PAGE_RW (_AT(pteval_t, 1) << _PAGE_BIT_RW) +#define _PAGE_USER (_AT(pteval_t, 1) << _PAGE_BIT_USER) +#define _PAGE_PWT (_AT(pteval_t, 1) << _PAGE_BIT_PWT) +#define _PAGE_PCD (_AT(pteval_t, 1) << _PAGE_BIT_PCD) +#define _PAGE_ACCESSED (_AT(pteval_t, 1) << _PAGE_BIT_ACCESSED) +#define _PAGE_DIRTY (_AT(pteval_t, 1) << _PAGE_BIT_DIRTY) +#define _PAGE_PSE (_AT(pteval_t, 1) << _PAGE_BIT_PSE) +#define _PAGE_GLOBAL (_AT(pteval_t, 1) << _PAGE_BIT_GLOBAL) +#define _PAGE_UNUSED1 (_AT(pteval_t, 1) << _PAGE_BIT_UNUSED1) +#define _PAGE_UNUSED2 (_AT(pteval_t, 1) << _PAGE_BIT_UNUSED2) +#define _PAGE_UNUSED3 (_AT(pteval_t, 1) << _PAGE_BIT_UNUSED3) +#define _PAGE_PAT (_AT(pteval_t, 1) << _PAGE_BIT_PAT) +#define _PAGE_PAT_LARGE (_AT(pteval_t, 1) << _PAGE_BIT_PAT_LARGE) #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE) -#define _PAGE_NX (_AC(1, ULL) << _PAGE_BIT_NX) +#define _PAGE_NX (_AT(pteval_t, 1) << _PAGE_BIT_NX) #else -#define _PAGE_NX 0 +#define _PAGE_NX (_AT(pteval_t, 0)) #endif /* If _PAGE_PRESENT is clear, we use these: */ @@ -210,22 +205,22 @@ static inline int pmd_large(pmd_t pte) static inline pte_t pte_mkclean(pte_t pte) { - return __pte(pte_val(pte) & ~(pteval_t)_PAGE_DIRTY); + return __pte(pte_val(pte) & ~_PAGE_DIRTY); } static inline pte_t pte_mkold(pte_t pte) { - return __pte(pte_val(pte) & ~(pteval_t)_PAGE_ACCESSED); + return __pte(pte_val(pte) & ~_PAGE_ACCESSED); } static inline pte_t pte_wrprotect(pte_t pte) { - return __pte(pte_val(pte) & ~(pteval_t)_PAGE_RW); + return __pte(pte_val(pte) & ~_PAGE_RW); } static inline pte_t pte_mkexec(pte_t pte) { - return __pte(pte_val(pte) & ~(pteval_t)_PAGE_NX); + return __pte(pte_val(pte) & ~_PAGE_NX); } static inline pte_t pte_mkdirty(pte_t pte) @@ -250,7 +245,7 @@ static inline pte_t pte_mkhuge(pte_t pte) static inline pte_t pte_clrhuge(pte_t pte) { - return __pte(pte_val(pte) & ~(pteval_t)_PAGE_PSE); + return __pte(pte_val(pte) & ~_PAGE_PSE); } static inline pte_t pte_mkglobal(pte_t pte) @@ -260,7 +255,7 @@ static inline pte_t pte_mkglobal(pte_t pte) static inline pte_t pte_clrglobal(pte_t pte) { - return __pte(pte_val(pte) & ~(pteval_t)_PAGE_GLOBAL); + return __pte(pte_val(pte) & ~_PAGE_GLOBAL); } static inline pte_t pte_mkspecial(pte_t pte) -- 2.39.5