From 06743521d0eae1263a09bccb1a92a9fbb94660b3 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Wed, 5 Nov 2014 21:57:39 +0530 Subject: [PATCH] powerpc/mm: Add missing pmd accessors This patch add documentation and missing accessors. Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/pgtable-ppc64-4k.h | 16 +++++- arch/powerpc/include/asm/pgtable-ppc64-64k.h | 3 ++ arch/powerpc/include/asm/pgtable-ppc64.h | 51 +++++++++++++++----- arch/powerpc/mm/hugetlbpage.c | 3 ++ arch/powerpc/mm/pgtable_64.c | 22 +++++++-- 5 files changed, 78 insertions(+), 17 deletions(-) diff --git a/arch/powerpc/include/asm/pgtable-ppc64-4k.h b/arch/powerpc/include/asm/pgtable-ppc64-4k.h index 7b935683f268..132ee1d482c2 100644 --- a/arch/powerpc/include/asm/pgtable-ppc64-4k.h +++ b/arch/powerpc/include/asm/pgtable-ppc64-4k.h @@ -57,7 +57,21 @@ #define pgd_present(pgd) (pgd_val(pgd) != 0) #define pgd_clear(pgdp) (pgd_val(*(pgdp)) = 0) #define pgd_page_vaddr(pgd) (pgd_val(pgd) & ~PGD_MASKED_BITS) -#define pgd_page(pgd) virt_to_page(pgd_page_vaddr(pgd)) + +#ifndef __ASSEMBLY__ + +static inline pte_t pgd_pte(pgd_t pgd) +{ + return __pte(pgd_val(pgd)); +} + +static inline pgd_t pte_pgd(pte_t pte) +{ + return __pgd(pte_val(pte)); +} +extern struct page *pgd_page(pgd_t pgd); + +#endif /* !__ASSEMBLY__ */ #define pud_offset(pgdp, addr) \ (((pud_t *) pgd_page_vaddr(*(pgdp))) + \ diff --git a/arch/powerpc/include/asm/pgtable-ppc64-64k.h b/arch/powerpc/include/asm/pgtable-ppc64-64k.h index a56b82fb0609..1de35bbd02a6 100644 --- a/arch/powerpc/include/asm/pgtable-ppc64-64k.h +++ b/arch/powerpc/include/asm/pgtable-ppc64-64k.h @@ -38,4 +38,7 @@ /* Bits to mask out from a PGD/PUD to get to the PMD page */ #define PUD_MASKED_BITS 0x1ff +#define pgd_pte(pgd) (pud_pte(((pud_t){ pgd }))) +#define pte_pgd(pte) ((pgd_t)pte_pud(pte)) + #endif /* _ASM_POWERPC_PGTABLE_PPC64_64K_H */ diff --git a/arch/powerpc/include/asm/pgtable-ppc64.h b/arch/powerpc/include/asm/pgtable-ppc64.h index ae153c40ab7c..d12092420560 100644 --- a/arch/powerpc/include/asm/pgtable-ppc64.h +++ b/arch/powerpc/include/asm/pgtable-ppc64.h @@ -152,7 +152,7 @@ #define pmd_none(pmd) (!pmd_val(pmd)) #define pmd_bad(pmd) (!is_kernel_addr(pmd_val(pmd)) \ || (pmd_val(pmd) & PMD_BAD_BITS)) -#define pmd_present(pmd) (pmd_val(pmd) != 0) +#define pmd_present(pmd) (!pmd_none(pmd)) #define pmd_clear(pmdp) (pmd_val(*(pmdp)) = 0) #define pmd_page_vaddr(pmd) (pmd_val(pmd) & ~PMD_MASKED_BITS) extern struct page *pmd_page(pmd_t pmd); @@ -164,9 +164,21 @@ extern struct page *pmd_page(pmd_t pmd); #define pud_present(pud) (pud_val(pud) != 0) #define pud_clear(pudp) (pud_val(*(pudp)) = 0) #define pud_page_vaddr(pud) (pud_val(pud) & ~PUD_MASKED_BITS) -#define pud_page(pud) virt_to_page(pud_page_vaddr(pud)) +extern struct page *pud_page(pud_t pud); + +static inline pte_t pud_pte(pud_t pud) +{ + return __pte(pud_val(pud)); +} + +static inline pud_t pte_pud(pte_t pte) +{ + return __pud(pte_val(pte)); +} +#define pud_write(pud) pte_write(pud_pte(pud)) #define pgd_set(pgdp, pudp) ({pgd_val(*(pgdp)) = (unsigned long)(pudp);}) +#define pgd_write(pgd) pte_write(pgd_pte(pgd)) /* * Find an entry in a page-table-directory. We combine the address region @@ -422,7 +434,22 @@ extern void set_pmd_at(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp, pmd_t pmd); extern void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long addr, pmd_t *pmd); - +/* + * + * For core kernel code by design pmd_trans_huge is never run on any hugetlbfs + * page. The hugetlbfs page table walking and mangling paths are totally + * separated form the core VM paths and they're differentiated by + * VM_HUGETLB being set on vm_flags well before any pmd_trans_huge could run. + * + * pmd_trans_huge() is defined as false at build time if + * CONFIG_TRANSPARENT_HUGEPAGE=n to optimize away code blocks at build + * time in such case. + * + * For ppc64 we need to differntiate from explicit hugepages from THP, because + * for THP we also track the subpage details at the pmd level. We don't do + * that for explicit huge pages. + * + */ static inline int pmd_trans_huge(pmd_t pmd) { /* @@ -431,16 +458,6 @@ static inline int pmd_trans_huge(pmd_t pmd) return (pmd_val(pmd) & 0x3) && (pmd_val(pmd) & _PAGE_THP_HUGE); } -static inline int pmd_large(pmd_t pmd) -{ - /* - * leaf pte for huge page, bottom two bits != 00 - */ - if (pmd_trans_huge(pmd)) - return pmd_val(pmd) & _PAGE_PRESENT; - return 0; -} - static inline int pmd_trans_splitting(pmd_t pmd) { if (pmd_trans_huge(pmd)) @@ -451,6 +468,14 @@ static inline int pmd_trans_splitting(pmd_t pmd) extern int has_transparent_hugepage(void); #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ +static inline int pmd_large(pmd_t pmd) +{ + /* + * leaf pte for huge page, bottom two bits != 00 + */ + return ((pmd_val(pmd) & 0x3) != 0x0); +} + static inline pte_t pmd_pte(pmd_t pmd) { return __pte(pmd_val(pmd)); diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c index b460e723f0ec..2b8e5ed28831 100644 --- a/arch/powerpc/mm/hugetlbpage.c +++ b/arch/powerpc/mm/hugetlbpage.c @@ -62,6 +62,9 @@ static unsigned nr_gpages; /* * We have PGD_INDEX_SIZ = 12 and PTE_INDEX_SIZE = 8, so that we can have * 16GB hugepage pte in PGD and 16MB hugepage pte at PMD; + * + * Defined in such a way that we can optimize away code block at build time + * if CONFIG_HUGETLB_PAGE=n. */ int pmd_huge(pmd_t pmd) { diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c index e0c718543174..87ff0c1908a9 100644 --- a/arch/powerpc/mm/pgtable_64.c +++ b/arch/powerpc/mm/pgtable_64.c @@ -35,6 +35,7 @@ #include #include #include +#include #include #include @@ -344,16 +345,31 @@ EXPORT_SYMBOL(iounmap); EXPORT_SYMBOL(__iounmap); EXPORT_SYMBOL(__iounmap_at); +#ifndef __PAGETABLE_PUD_FOLDED +/* 4 level page table */ +struct page *pgd_page(pgd_t pgd) +{ + if (pgd_huge(pgd)) + return pte_page(pgd_pte(pgd)); + return virt_to_page(pgd_page_vaddr(pgd)); +} +#endif + +struct page *pud_page(pud_t pud) +{ + if (pud_huge(pud)) + return pte_page(pud_pte(pud)); + return virt_to_page(pud_page_vaddr(pud)); +} + /* * For hugepage we have pfn in the pmd, we use PTE_RPN_SHIFT bits for flags * For PTE page, we have a PTE_FRAG_SIZE (4K) aligned virtual address. */ struct page *pmd_page(pmd_t pmd) { -#ifdef CONFIG_TRANSPARENT_HUGEPAGE - if (pmd_trans_huge(pmd)) + if (pmd_trans_huge(pmd) || pmd_huge(pmd)) return pfn_to_page(pmd_pfn(pmd)); -#endif return virt_to_page(pmd_page_vaddr(pmd)); } -- 2.20.1