xref: /netbsd-src/sys/arch/xen/include/xen_shm.h (revision c24c993fe4cf289234b8ce9b47d92eb1278cfbda)
1 /*      $NetBSD: xen_shm.h,v 1.12 2020/04/25 15:26:17 bouyer Exp $      */
2 
3 /*
4  * Copyright (c) 2005 Manuel Bouyer.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  *
26  */
27 
28 #include "opt_xen.h"
29 
30 #define XENSHM_MAX_PAGES_PER_REQUEST ((MAXPHYS + PAGE_SIZE) >> PAGE_SHIFT)
31 
32 /*
33  * Helper routines for the backend drivers. This implement the necessary
34  * functions to map a bunch of pages from foreign domains in our kernel VM
35  * space, do I/O to it, and unmap it.
36  */
37 
38 int  xen_shm_map(int, int, grant_ref_t *, vaddr_t, grant_handle_t *, int);
39 void xen_shm_unmap(vaddr_t, int, grant_handle_t *);
40 
41 /* flags for xen_shm_map() */
42 #define XSHM_RO 0x02		/* map the guest's memory read-only */
43