xref: /titanic_51/usr/src/uts/common/xen/sys/gnttab.h (revision dd51520e127b452179a2ce4ea3bd8dee949f9afe)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #ifndef	_SYS_GNTTAB_H
28 #define	_SYS_GNTTAB_H
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 /*
33  * gnttab.h
34  *
35  * Two sets of functionality:
36  * 1. Granting foreign access to our memory reservation.
37  * 2. Accessing others' memory reservations via grant references.
38  * (i.e., mechanisms for both sender and recipient of grant references)
39  *
40  * Copyright (c) 2004-2005, K A Fraser
41  * Copyright (c) 2005, Christopher Clark
42  *
43  * This program is free software; you can redistribute it and/or
44  * modify it under the terms of the GNU General Public License version 2
45  * as published by the Free Software Foundation; or, when distributed
46  * separately from the Linux kernel or incorporated into other
47  * software packages, subject to the following license:
48  *
49  * Permission is hereby granted, free of charge, to any person obtaining a copy
50  * of this source file (the "Software"), to deal in the Software without
51  * restriction, including without limitation the rights to use, copy, modify,
52  * merge, publish, distribute, sublicense, and/or sell copies of the Software,
53  * and to permit persons to whom the Software is furnished to do so, subject to
54  * the following conditions:
55  *
56  * The above copyright notice and this permission notice shall be included in
57  * all copies or substantial portions of the Software.
58  *
59  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
60  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
61  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
62  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
63  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
64  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
65  * IN THE SOFTWARE.
66  */
67 
68 #include <sys/hypervisor.h>
69 #include <xen/public/grant_table.h>
70 #include <xen/public/features.h>
71 
72 #ifdef __cplusplus
73 extern "C" {
74 #endif
75 
76 struct gnttab_free_callback {
77 	struct gnttab_free_callback *next;
78 	void (*fn)(void *);
79 	void *arg;
80 	uint16_t count;
81 };
82 
83 /*
84  * For i86xpv the "frames" in grant table terminology are really MFNs.
85  */
86 typedef mfn_t gnttab_frame_t;
87 #define	FRAME_TO_MA(f)	((maddr_t)(f) << PAGESHIFT)
88 
89 int gnttab_grant_foreign_access(domid_t, gnttab_frame_t, int readonly);
90 
91 /*
92  * End access through the given grant reference, iff the grant entry is no
93  * longer in use.  Return 1 if the grant entry was freed, 0 if it is still in
94  * use.
95  */
96 int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly);
97 
98 /*
99  * Eventually end access through the given grant reference, and once that
100  * access has been ended, free the given page too.  Access will be ended
101  * immediately iff the grant entry is not in use, otherwise it will happen
102  * some time later.  page may be 0, in which case no freeing will occur.
103  */
104 void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
105 	gnttab_frame_t page);
106 
107 int gnttab_grant_foreign_transfer(domid_t domid, pfn_t pfn);
108 
109 gnttab_frame_t gnttab_end_foreign_transfer_ref(grant_ref_t ref);
110 gnttab_frame_t gnttab_end_foreign_transfer(grant_ref_t ref);
111 
112 int gnttab_query_foreign_access(grant_ref_t ref);
113 
114 /*
115  * operations on reserved batches of grant references
116  */
117 int gnttab_alloc_grant_references(uint16_t count, grant_ref_t *pprivate_head);
118 
119 void gnttab_free_grant_reference(grant_ref_t ref);
120 
121 void gnttab_free_grant_references(grant_ref_t head);
122 
123 int gnttab_empty_grant_references(const grant_ref_t *pprivate_head);
124 
125 int gnttab_claim_grant_reference(grant_ref_t *pprivate_head);
126 
127 void gnttab_release_grant_reference(grant_ref_t *private_head,
128 	grant_ref_t release);
129 
130 void gnttab_request_free_callback(struct gnttab_free_callback *callback,
131 	void (*fn)(void *), void *arg, uint16_t count);
132 
133 void gnttab_cancel_free_callback(struct gnttab_free_callback *callback);
134 
135 void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
136 	gnttab_frame_t frame, int readonly);
137 
138 void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid,
139 	pfn_t pfn);
140 
141 #define	gnttab_map_vaddr(map) ((void *)(map.host_virt_addr))
142 
143 /*
144  * framework
145  */
146 void gnttab_init(void);
147 void gnttab_suspend(void);
148 void gnttab_resume(void);
149 
150 #ifdef	__cplusplus
151 }
152 #endif
153 
154 #endif /* _SYS_GNTTAB_H */
155