From: Zi Yan <[email protected]> This prepares for PUD THP support, which allocates 512 of such PMD pages when creating a PUD THP. These page table pages will be withdrawn during THP split.
Signed-off-by: Zi Yan <[email protected]> --- arch/x86/include/asm/pgalloc.h | 60 ++++++++++++++++++++++++++++++++++ arch/x86/mm/pgtable.c | 25 ++++++++++++++ include/linux/huge_mm.h | 3 ++ 3 files changed, 88 insertions(+) diff --git a/arch/x86/include/asm/pgalloc.h b/arch/x86/include/asm/pgalloc.h index 62ad61d6fefc..b24284522973 100644 --- a/arch/x86/include/asm/pgalloc.h +++ b/arch/x86/include/asm/pgalloc.h @@ -52,6 +52,19 @@ extern pgd_t *pgd_alloc(struct mm_struct *); extern void pgd_free(struct mm_struct *mm, pgd_t *pgd); extern pgtable_t pte_alloc_one(struct mm_struct *); +extern pgtable_t pte_alloc_order(struct mm_struct *mm, unsigned long address, + int order); + +static inline void pte_free_order(struct mm_struct *mm, struct page *pte, + int order) +{ + int i; + + for (i = 0; i < (1<<order); i++) { + pgtable_pte_page_dtor(&pte[i]); + __free_page(&pte[i]); + } +} extern void ___pte_free_tlb(struct mmu_gather *tlb, struct page *pte); @@ -87,6 +100,53 @@ static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd, #define pmd_pgtable(pmd) pmd_page(pmd) #if CONFIG_PGTABLE_LEVELS > 2 +static inline pmd_t *pmd_alloc_one_page_with_ptes(struct mm_struct *mm, unsigned long addr) +{ + pgtable_t pte_pgtables; + pmd_t *pmd; + spinlock_t *pmd_ptl; + int i; + + pte_pgtables = pte_alloc_order(mm, addr, + HPAGE_PUD_ORDER - HPAGE_PMD_ORDER); + if (!pte_pgtables) + return NULL; + + pmd = pmd_alloc_one(mm, addr); + if (unlikely(!pmd)) { + pte_free_order(mm, pte_pgtables, + HPAGE_PUD_ORDER - HPAGE_PMD_ORDER); + return NULL; + } + pmd_ptl = pmd_lock(mm, pmd); + + for (i = 0; i < (1<<(HPAGE_PUD_ORDER - HPAGE_PMD_ORDER)); i++) + pgtable_trans_huge_deposit(mm, pmd, pte_pgtables + i); + + spin_unlock(pmd_ptl); + + return pmd; +} + +static inline void pmd_free_page_with_ptes(struct mm_struct *mm, pmd_t *pmd) +{ + spinlock_t *pmd_ptl; + int i; + + BUG_ON((unsigned long)pmd & (PAGE_SIZE-1)); + pmd_ptl = pmd_lock(mm, pmd); + + for (i = 0; i < (1<<(HPAGE_PUD_ORDER - HPAGE_PMD_ORDER)); i++) { + pgtable_t pte_pgtable; + + pte_pgtable = pgtable_trans_huge_withdraw(mm, pmd); + pte_free(mm, pte_pgtable); + } + + spin_unlock(pmd_ptl); + pmd_free(mm, pmd); +} + extern void ___pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd); static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd, diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index dfd82f51ba66..7be73aee6183 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -33,6 +33,31 @@ pgtable_t pte_alloc_one(struct mm_struct *mm) return __pte_alloc_one(mm, __userpte_alloc_gfp); } +pgtable_t pte_alloc_order(struct mm_struct *mm, unsigned long address, int order) +{ + struct page *pte; + int i; + + pte = alloc_pages(__userpte_alloc_gfp, order); + if (!pte) + return NULL; + split_page(pte, order); + for (i = 1; i < (1 << order); i++) + set_page_private(pte + i, 0); + + for (i = 0; i < (1<<order); i++) { + if (!pgtable_pte_page_ctor(&pte[i])) { + __free_page(&pte[i]); + while (--i >= 0) { + pgtable_pte_page_dtor(&pte[i]); + __free_page(&pte[i]); + } + return NULL; + } + } + return pte; +} + static int __init setup_userpte(char *arg) { if (!arg) diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 8a8bc46a2432..e9d228d4fc69 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -115,6 +115,9 @@ extern struct kobj_attribute shmem_enabled_attr; #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT) #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER) +#define HPAGE_PUD_ORDER (HPAGE_PUD_SHIFT-PAGE_SHIFT) +#define HPAGE_PUD_NR (1<<HPAGE_PUD_ORDER) + #ifdef CONFIG_TRANSPARENT_HUGEPAGE #define HPAGE_PMD_SHIFT PMD_SHIFT #define HPAGE_PMD_SIZE ((1UL) << HPAGE_PMD_SHIFT) -- 2.28.0
