On Thu, Apr 04, 2013 at 11:27:57AM +0530, Aneesh Kumar K.V wrote: > From: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxxxxxxx> > > HUGETLB clear the top bit of PMD entries and use that to indicate > a HUGETLB page directory. Since we store pfns in PMDs for THP, > we would have the top bit cleared by default. Add the top bit mask > for THP PMD entries and clear that when we are looking for pmd_pfn. > > @@ -44,6 +44,14 @@ struct mm_struct; > #define PMD_HUGE_RPN_SHIFT PTE_RPN_SHIFT > #define HUGE_PAGE_SIZE (ASM_CONST(1) << 24) > #define HUGE_PAGE_MASK (~(HUGE_PAGE_SIZE - 1)) > +/* > + * HugeTLB looks at the top bit of the Linux page table entries to > + * decide whether it is a huge page directory or not. Mark HUGE > + * PMD to differentiate > + */ > +#define PMD_HUGE_NOT_HUGETLB (ASM_CONST(1) << 63) > +#define PMD_ISHUGE (_PMD_ISHUGE | PMD_HUGE_NOT_HUGETLB) > +#define PMD_HUGE_PROTBITS (0xfff | PMD_HUGE_NOT_HUGETLB) > > #ifndef __ASSEMBLY__ > extern void hpte_need_hugepage_flush(struct mm_struct *mm, unsigned long addr, > @@ -84,7 +93,8 @@ static inline unsigned long pmd_pfn(pmd_t pmd) > /* > * Only called for hugepage pmd > */ > - return pmd_val(pmd) >> PMD_HUGE_RPN_SHIFT; > + unsigned long val = pmd_val(pmd) & ~PMD_HUGE_PROTBITS; > + return val >> PMD_HUGE_RPN_SHIFT; > } This is breaking the 32-bit build for me (pmac32_defconfig): arch/powerpc/include/asm/pgtable.h:123:2: error: left shift count >= width of type [-Werror] cheers -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>