diff --git a/include/linux/dax.h b/include/linux/dax.h
index bbe79ed..28e398f 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -78,6 +78,8 @@
 void *dax_get_private(struct dax_device *dax_dev);
 long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
 		void **kaddr, pfn_t *pfn);
+size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
+		size_t bytes, struct iov_iter *i);
 
 /*
  * We use lowest available bit in exceptional entry for locking, one bit for