--- /dev/null
+/*
+ * Copyright (C) 2006 Hollis Blanchard <hollisb@us.ibm.com>, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef _XEN_XENCOMM_H_
+#define _XEN_XENCOMM_H_
+
+/* A xencomm descriptor is a scatter/gather list containing physical
+ * addresses corresponding to a virtually contiguous memory area. The
+ * hypervisor translates these physical addresses to machine addresses to copy
+ * to and from the virtually contiguous area.
+ */
+
+#define XENCOMM_MAGIC 0x58434F4D /* 'XCOM' */
+#define XENCOMM_INVALID (~0UL)
+
+struct xencomm_desc {
+ uint32_t magic;
+ uint32_t nr_addrs; /* the number of entries in address[] */
+ uint64_t address[0];
+};
+
+#endif /* _XEN_XENCOMM_H_ */