From: Kumar Gala <[EMAIL PROTECTED]> Allow the pfn to be offset by more than just PAGE_SHIFT in the pte. Today, PAGE_SHIFT tends to allow us to have 12-bits of flags in the pte. In the future if we have a larger pte we can allocate more bits for flags by offsetting the pfn even further.
Signed-off-by: Kumar Gala <[EMAIL PROTECTED]> Signed-off-by: Andrew Morton <[EMAIL PROTECTED]> --- 25-akpm/include/asm-ppc/pgtable.h | 9 +++++++-- 1 files changed, 7 insertions(+), 2 deletions(-) diff -puN include/asm-ppc/pgtable.h~ppc32-allow-adjust-of-pfn-offset-in-pte include/asm-ppc/pgtable.h --- 25/include/asm-ppc/pgtable.h~ppc32-allow-adjust-of-pfn-offset-in-pte 2005-04-12 03:21:11.573377480 -0700 +++ 25-akpm/include/asm-ppc/pgtable.h 2005-04-12 03:21:11.576377024 -0700 @@ -431,10 +431,15 @@ extern unsigned long bad_call_to_PMD_PAG * Conversions between PTE values and page frame numbers. */ -#define pte_pfn(x) (pte_val(x) >> PAGE_SHIFT) +/* in some case we want to additionaly adjust where the pfn is in the pte to + * allow room for more flags */ +#define PFN_SHIFT_OFFSET (PAGE_SHIFT) + +#define pte_pfn(x) (pte_val(x) >> PFN_SHIFT_OFFSET) #define pte_page(x) pfn_to_page(pte_pfn(x)) -#define pfn_pte(pfn, prot) __pte(((pte_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)) +#define pfn_pte(pfn, prot) __pte(((pte_basic_t)(pfn) << PFN_SHIFT_OFFSET) |\ + pgprot_val(prot)) #define mk_pte(page, prot) pfn_pte(page_to_pfn(page), prot) /* _ - 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/
