diff --git a/fs/dax.c b/fs/dax.c index 9593f4bee32774e06fa5c8be7d1b24634cb8d0c0..d778e5f1a01cf3ff76e4f222f43bed90bf5d2774 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 f9b612fec4dd8242ca20fe2d0e45c8b520ad273f..ecb080d6ff42077513f03b95537dc108bded9e07 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 96dfd9d81fcb2231209167f402b4c9f9f2308fbc..3e574efad8f853eb0545490d9a4b0ce4ef909df4 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) {