diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 67a71191136e..38633864a93e 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2008,7 +2008,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, entry = huge_ptep_get(ptep); if (huge_pte_none(entry)) { ret = hugetlb_no_page(mm, vma, address, ptep, write_access); - goto out_unlock; + goto out_mutex; } ret = 0; @@ -2024,7 +2024,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, if (write_access && !pte_write(entry)) { if (vma_needs_reservation(h, vma, address) < 0) { ret = VM_FAULT_OOM; - goto out_unlock; + goto out_mutex; } if (!(vma->vm_flags & VM_SHARED)) @@ -2034,10 +2034,23 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, spin_lock(&mm->page_table_lock); /* Check for a racing update before calling hugetlb_cow */ - if (likely(pte_same(entry, huge_ptep_get(ptep)))) - if (write_access && !pte_write(entry)) + if (unlikely(!pte_same(entry, huge_ptep_get(ptep)))) + goto out_page_table_lock; + + + if (write_access) { + if (!pte_write(entry)) { ret = hugetlb_cow(mm, vma, address, ptep, entry, pagecache_page); + goto out_page_table_lock; + } + entry = pte_mkdirty(entry); + } + entry = pte_mkyoung(entry); + if (huge_ptep_set_access_flags(vma, address, ptep, entry, write_access)) + update_mmu_cache(vma, address, entry); + +out_page_table_lock: spin_unlock(&mm->page_table_lock); if (pagecache_page) { @@ -2045,7 +2058,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, put_page(pagecache_page); } -out_unlock: +out_mutex: mutex_unlock(&hugetlb_instantiation_mutex); return ret;