include/xen/interface/xencomm.h

   1 /*
   2  * Permission is hereby granted, free of charge, to any person obtaining a copy
   3  * of this software and associated documentation files (the "Software"), to
   4  * deal in the Software without restriction, including without limitation the
   5  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
   6  * sell copies of the Software, and to permit persons to whom the Software is
   7  * furnished to do so, subject to the following conditions:
   8  *
   9  * The above copyright notice and this permission notice shall be included in
  10  * all copies or substantial portions of the Software.
  11  *
  12  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  13  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  14  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  15  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  16  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  17  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  18  * DEALINGS IN THE SOFTWARE.
  19  *
  20  * Copyright (C) IBM Corp. 2006
  21  */
  22
  23 #ifndef _XEN_XENCOMM_H_
  24 #define _XEN_XENCOMM_H_
  25
  26 /* A xencomm descriptor is a scatter/gather list containing physical
  27  * addresses corresponding to a virtually contiguous memory area. The
  28  * hypervisor translates these physical addresses to machine addresses to copy
  29  * to and from the virtually contiguous area.
  30  */
  31
  32 #define XENCOMM_MAGIC 0x58434F4D /* 'XCOM' */
  33 #define XENCOMM_INVALID (~0UL)
  34
  35 struct xencomm_desc {
  36     uint32_t magic;
  37     uint32_t nr_addrs; /* the number of entries in address[] */
  38     uint64_t address[0];
  39 };
  40
  41 #endif /* _XEN_XENCOMM_H_ */