diff --git a/fs/9p/v9fs_vfs.h b/fs/9p/v9fs_vfs.h
index f867b8d..450b0c1 100644
--- a/fs/9p/v9fs_vfs.h
+++ b/fs/9p/v9fs_vfs.h
@@ -38,7 +38,7 @@
  */
 
 extern struct file_system_type v9fs_fs_type;
-extern struct address_space_operations v9fs_addr_operations;
+extern const struct address_space_operations v9fs_addr_operations;
 extern const struct file_operations v9fs_file_operations;
 extern const struct file_operations v9fs_dir_operations;
 extern struct dentry_operations v9fs_dentry_operations;