+/*
+ * Apply policy to a single VMA
+ * This must be called with the mmap_sem held for writing.
+ */
+static int vma_replace_policy(struct vm_area_struct *vma,
+ struct mempolicy *pol)
+{
+ int err;
+ struct mempolicy *old;
+ struct mempolicy *new;
+
+ pr_debug("vma %lx-%lx/%lx vm_ops %p vm_file %p set_policy %p\n",
+ vma->vm_start, vma->vm_end, vma->vm_pgoff,
+ vma->vm_ops, vma->vm_file,
+ vma->vm_ops ? vma->vm_ops->set_policy : NULL);
+
+ new = mpol_dup(pol);
+ if (IS_ERR(new))
+ return PTR_ERR(new);
+
+ if (vma->vm_ops && vma->vm_ops->set_policy) {
+ err = vma->vm_ops->set_policy(vma, new);
+ if (err)
+ goto err_out;
+ }
+
+ old = vma->vm_policy;
+ vma->vm_policy = new; /* protected by mmap_sem */
+ mpol_put(old);
+
+ return 0;
+ err_out:
+ mpol_put(new);
+ return err;
+}
+