This patch introduces pgprot_writethrough() for setting the WT type for a given pgprot_t.
Signed-off-by: Toshi Kani <[email protected]> --- arch/x86/include/asm/pgtable_types.h | 3 +++ arch/x86/mm/pat.c | 9 +++++++++ include/asm-generic/pgtable.h | 4 ++++ 3 files changed, 16 insertions(+) diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index 7b905cb..1fe8af7 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -343,6 +343,9 @@ extern int nx_enabled; #define pgprot_writecombine pgprot_writecombine extern pgprot_t pgprot_writecombine(pgprot_t prot); +#define pgprot_writethrough pgprot_writethrough +extern pgprot_t pgprot_writethrough(pgprot_t prot); + /* Indicate that x86 has its own track and untrack pfn vma functions */ #define __HAVE_PFNMAP_TRACKING diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index 8a8be17..a987071 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -796,6 +796,15 @@ pgprot_t pgprot_writecombine(pgprot_t prot) } EXPORT_SYMBOL_GPL(pgprot_writecombine); +pgprot_t pgprot_writethrough(pgprot_t prot) +{ + if (pat_enabled) + return __pgprot(pgprot_val(prot) | _PAGE_CACHE_WT); + else + return pgprot_noncached(prot); +} +EXPORT_SYMBOL_GPL(pgprot_writethrough); + #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT) static struct memtype *memtype_get_idx(loff_t pos) diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index 53b2acc..1af0ed9 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -249,6 +249,10 @@ static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b) #define pgprot_writecombine pgprot_noncached #endif +#ifndef pgprot_writethrough +#define pgprot_writethrough pgprot_noncached +#endif + /* * When walking page tables, get the address of the next boundary, * or the end address of the range if that comes earlier. Although no -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
