v4.19.13 snapshot.
diff --git a/include/linux/aio.h b/include/linux/aio.h
new file mode 100644
index 0000000..b83e68d
--- /dev/null
+++ b/include/linux/aio.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __LINUX__AIO_H
+#define __LINUX__AIO_H
+
+#include <linux/aio_abi.h>
+
+struct kioctx;
+struct kiocb;
+struct mm_struct;
+
+typedef int (kiocb_cancel_fn)(struct kiocb *);
+
+/* prototypes */
+#ifdef CONFIG_AIO
+extern void exit_aio(struct mm_struct *mm);
+void kiocb_set_cancel_fn(struct kiocb *req, kiocb_cancel_fn *cancel);
+#else
+static inline void exit_aio(struct mm_struct *mm) { }
+static inline void kiocb_set_cancel_fn(struct kiocb *req,
+ kiocb_cancel_fn *cancel) { }
+#endif /* CONFIG_AIO */
+
+/* for sysctl: */
+extern unsigned long aio_nr;
+extern unsigned long aio_max_nr;
+
+#endif /* __LINUX__AIO_H */