v4.19.13 snapshot.
diff --git a/include/xen/interface/io/xenbus.h b/include/xen/interface/io/xenbus.h
new file mode 100644
index 0000000..aaf2951
--- /dev/null
+++ b/include/xen/interface/io/xenbus.h
@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*****************************************************************************
+ * xenbus.h
+ *
+ * Xenbus protocol details.
+ *
+ * Copyright (C) 2005 XenSource Ltd.
+ */
+
+#ifndef _XEN_PUBLIC_IO_XENBUS_H
+#define _XEN_PUBLIC_IO_XENBUS_H
+
+/* The state of either end of the Xenbus, i.e. the current communication
+   status of initialisation across the bus.  States here imply nothing about
+   the state of the connection between the driver and the kernel's device
+   layers.  */
+enum xenbus_state
+{
+	XenbusStateUnknown      = 0,
+	XenbusStateInitialising = 1,
+	XenbusStateInitWait     = 2,  /* Finished early
+					 initialisation, but waiting
+					 for information from the peer
+					 or hotplug scripts. */
+	XenbusStateInitialised  = 3,  /* Initialised and waiting for a
+					 connection from the peer. */
+	XenbusStateConnected    = 4,
+	XenbusStateClosing      = 5,  /* The device is being closed
+					 due to an error or an unplug
+					 event. */
+	XenbusStateClosed       = 6,
+
+	/*
+	* Reconfiguring: The device is being reconfigured.
+	*/
+	XenbusStateReconfiguring = 7,
+
+	XenbusStateReconfigured  = 8
+};
+
+#endif /* _XEN_PUBLIC_IO_XENBUS_H */
+
+/*
+ * Local variables:
+ *  c-file-style: "linux"
+ *  indent-tabs-mode: t
+ *  c-indent-level: 8
+ *  c-basic-offset: 8
+ *  tab-width: 8
+ * End:
+ */