1 files changed, 2 insertions, 9 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index 971dd2cb77d2..79bcc9f92e48 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -612,8 +612,6 @@ static unsigned long count_vma_pages_range(struct mm_struct *mm,
 void __vma_link_rb(struct mm_struct *mm, struct vm_area_struct *vma,
                 struct rb_node **rb_link, struct rb_node *rb_parent)
 {
-        WARN_ONCE(vma->vm_file && !vma->vm_ops, "missing vma->vm_ops");
-
         /* Update tracking information for the gap following the new vma. */
         if (vma->vm_next)
                 vma_gap_update(vma->vm_next);
@@ -1492,13 +1490,14 @@ SYSCALL_DEFINE1(old_mmap, struct mmap_arg_struct __user *, arg)
 int vma_wants_writenotify(struct vm_area_struct *vma)
 {
         vm_flags_t vm_flags = vma->vm_flags;
+        const struct vm_operations_struct *vm_ops = vma->vm_ops;
 
         /* If it was private or non-writable, the write bit is already clear */
         if ((vm_flags & (VM_WRITE|VM_SHARED)) != ((VM_WRITE|VM_SHARED)))
                 return 0;
 
         /* The backer wishes to know when pages are first written to? */
-        if (vma->vm_ops && vma->vm_ops->page_mkwrite)
+        if (vm_ops && (vm_ops->page_mkwrite || vm_ops->pfn_mkwrite))
                 return 1;
 
         /* The open routine did something to the protections that pgprot_modify
@@ -1638,12 +1637,6 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
                  */
                 WARN_ON_ONCE(addr != vma->vm_start);
 
-                /* All file mapping must have ->vm_ops set */
-                if (!vma->vm_ops) {
-                        static const struct vm_operations_struct dummy_ops = {};
-                        vma->vm_ops = &dummy_ops;
-                }
-
                 addr = vma->vm_start;
                 vm_flags = vma->vm_flags;
         } else if (vm_flags & VM_SHARED) {