fork: defer linking file vma until vma is fully initialized

[linux-2.6-block.git] / kernel / fork.c

diff --git a/kernel/fork.c b/kernel/fork.c
index 39a5046c2f0bf49e1bcade15c4c3c5574742b09d..aebb3e6c96dc62e5818ce16e31779868ea669067 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -714,6 +714,23 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
                } else if (anon_vma_fork(tmp, mpnt))
                        goto fail_nomem_anon_vma_fork;
                vm_flags_clear(tmp, VM_LOCKED_MASK);
+               /*
+                * Copy/update hugetlb private vma information.
+                */
+               if (is_vm_hugetlb_page(tmp))
+                       hugetlb_dup_vma_private(tmp);
+
+               /*
+                * Link the vma into the MT. After using __mt_dup(), memory
+                * allocation is not necessary here, so it cannot fail.
+                */
+               vma_iter_bulk_store(&vmi, tmp);
+
+               mm->map_count++;
+
+               if (tmp->vm_ops && tmp->vm_ops->open)
+                       tmp->vm_ops->open(tmp);
+
                file = tmp->vm_file;
                if (file) {
                        struct address_space *mapping = file->f_mapping;
@@ -730,25 +747,9 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
                        i_mmap_unlock_write(mapping);
                }
 
-               /*
-                * Copy/update hugetlb private vma information.
-                */
-               if (is_vm_hugetlb_page(tmp))
-                       hugetlb_dup_vma_private(tmp);
-
-               /*
-                * Link the vma into the MT. After using __mt_dup(), memory
-                * allocation is not necessary here, so it cannot fail.
-                */
-               vma_iter_bulk_store(&vmi, tmp);
-
-               mm->map_count++;
                if (!(tmp->vm_flags & VM_WIPEONFORK))
                        retval = copy_page_range(tmp, mpnt);
 
-               if (tmp->vm_ops && tmp->vm_ops->open)
-                       tmp->vm_ops->open(tmp);
-
                if (retval) {
                        mpnt = vma_next(&vmi);
                        goto loop_out;