diff --git a/libc/kernel/uapi/xen/gntalloc.h b/libc/kernel/uapi/xen/gntalloc.h
new file mode 100644
index 0000000..2076843
--- /dev/null
+++ b/libc/kernel/uapi/xen/gntalloc.h
@@ -0,0 +1,49 @@
+/****************************************************************************
+ ****************************************************************************
+ ***
+ ***   This header was automatically generated from a Linux kernel header
+ ***   of the same name, to make information necessary for userspace to
+ ***   call into the kernel available to libc.  It contains only constants,
+ ***   structures, and macros generated from the original header, and thus,
+ ***   contains no copyrightable information.
+ ***
+ ***   To edit the content of this header, modify the corresponding
+ ***   source file (e.g. under external/kernel-headers/original/) then
+ ***   run bionic/libc/kernel/tools/update_all.py
+ ***
+ ***   Any manual change here will be lost the next time this script will
+ ***   be run. You've been warned!
+ ***
+ ****************************************************************************
+ ****************************************************************************/
+#ifndef __LINUX_PUBLIC_GNTALLOC_H__
+#define __LINUX_PUBLIC_GNTALLOC_H__
+#define IOCTL_GNTALLOC_ALLOC_GREF  _IOC(_IOC_NONE, 'G', 5, sizeof(struct ioctl_gntalloc_alloc_gref))
+struct ioctl_gntalloc_alloc_gref {
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
+ uint16_t domid;
+ uint16_t flags;
+ uint32_t count;
+ uint64_t index;
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
+ uint32_t gref_ids[1];
+};
+#define GNTALLOC_FLAG_WRITABLE 1
+#define IOCTL_GNTALLOC_DEALLOC_GREF  _IOC(_IOC_NONE, 'G', 6, sizeof(struct ioctl_gntalloc_dealloc_gref))
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
+struct ioctl_gntalloc_dealloc_gref {
+ uint64_t index;
+ uint32_t count;
+};
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
+#define IOCTL_GNTALLOC_SET_UNMAP_NOTIFY  _IOC(_IOC_NONE, 'G', 7, sizeof(struct ioctl_gntalloc_unmap_notify))
+struct ioctl_gntalloc_unmap_notify {
+ uint64_t index;
+ uint32_t action;
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
+ uint32_t event_channel_port;
+};
+#define UNMAP_NOTIFY_CLEAR_BYTE 0x1
+#define UNMAP_NOTIFY_SEND_EVENT 0x2
+/* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
+#endif