From d295e3415a88ae63a37a22652808b20c7fcb970e Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Tue, 8 Sep 2015 14:59:34 -0700 Subject: [PATCH] dax: don't use set_huge_zero_page() This is another place where DAX assumed that pgtable_t was a pointer. Open code the important parts of set_huge_zero_page() in DAX and make set_huge_zero_page() static again. Signed-off-by: Kirill A. Shutemov Signed-off-by: Matthew Wilcox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/dax.c | 18 ++++++++++++------ include/linux/huge_mm.h | 3 --- mm/huge_memory.c | 2 +- 3 files changed, 13 insertions(+), 10 deletions(-) diff --git a/fs/dax.c b/fs/dax.c index 9593f4b..d778e5f 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -572,18 +572,24 @@ int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address, unmap_mapping_range(mapping, pgoff << PAGE_SHIFT, PMD_SIZE, 0); if (!write && !buffer_mapped(&bh) && buffer_uptodate(&bh)) { - bool set; spinlock_t *ptl; - struct mm_struct *mm = vma->vm_mm; + pmd_t entry; struct page *zero_page = get_huge_zero_page(); + if (unlikely(!zero_page)) goto fallback; - ptl = pmd_lock(mm, pmd); - set = set_huge_zero_page(NULL, mm, vma, pmd_addr, pmd, - zero_page); - spin_unlock(ptl); + ptl = pmd_lock(vma->vm_mm, pmd); + if (!pmd_none(*pmd)) { + spin_unlock(ptl); + goto fallback; + } + + entry = mk_pmd(zero_page, vma->vm_page_prot); + entry = pmd_mkhuge(entry); + set_pmd_at(vma->vm_mm, pmd_addr, pmd, entry); result = VM_FAULT_NOPAGE; + spin_unlock(ptl); } else { sector = bh.b_blocknr << (blkbits - 9); length = bdev_direct_access(bh.b_bdev, sector, &kaddr, &pfn, diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index f9b612f..ecb080d 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -163,9 +163,6 @@ static inline bool is_huge_zero_pmd(pmd_t pmd) } struct page *get_huge_zero_page(void); -bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm, - struct vm_area_struct *vma, unsigned long haddr, - pmd_t *pmd, struct page *zero_page); #else /* CONFIG_TRANSPARENT_HUGEPAGE */ #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; }) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 96dfd9d..3e574ef 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -790,7 +790,7 @@ static inline gfp_t alloc_hugepage_gfpmask(int defrag, gfp_t extra_gfp) } /* Caller must hold page table lock. */ -bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm, +static bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm, struct vm_area_struct *vma, unsigned long haddr, pmd_t *pmd, struct page *zero_page) { -- 2.7.4