[PATCH v7 5/9] arm64: hugetlb: Handle swap entries in huge_pte_offset() for contiguous hugepages
From: Punit Agrawal <hidden>
Date: 2017-08-22 10:44:25
Also in:
linux-mm
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
huge_pte_offset() was updated to correctly handle swap entries for hugepages. With the addition of the size parameter, it is now possible to disambiguate whether the request is for a regular hugepage or a contiguous hugepage. Fix huge_pte_offset() for contiguous hugepages by using the size to find the correct page table entry. Signed-off-by: Punit Agrawal <redacted> Cc: David Woods <redacted> --- arch/arm64/mm/hugetlbpage.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 594232598cac..b95e24dc3477 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c@@ -214,6 +214,7 @@ pte_t *huge_pte_offset(struct mm_struct *mm, pgd_t *pgd; pud_t *pud; pmd_t *pmd; + pte_t *pte; pgd = pgd_offset(mm, addr); pr_debug("%s: addr:0x%lx pgd:%p\n", __func__, addr, pgd);
@@ -221,19 +222,29 @@ pte_t *huge_pte_offset(struct mm_struct *mm, return NULL; pud = pud_offset(pgd, addr); - if (pud_none(*pud)) + if (sz != PUD_SIZE && pud_none(*pud)) return NULL; - /* swap or huge page */ - if (!pud_present(*pud) || pud_huge(*pud)) + /* hugepage or swap? */ + if (pud_huge(*pud) || !pud_present(*pud)) return (pte_t *)pud; /* table; check the next level */ + if (sz == CONT_PMD_SIZE) + addr &= CONT_PMD_MASK; + pmd = pmd_offset(pud, addr); - if (pmd_none(*pmd)) + if (!(sz == PMD_SIZE || sz == CONT_PMD_SIZE) && + pmd_none(*pmd)) return NULL; - if (!pmd_present(*pmd) || pmd_huge(*pmd)) + if (pmd_huge(*pmd) || !pmd_present(*pmd)) return (pte_t *)pmd; + if (sz == CONT_PTE_SIZE) { + pte = pte_offset_kernel( + pmd, (addr & CONT_PTE_MASK)); + return pte; + } + return NULL; }
--
2.13.2