xref: /freebsd/sys/xen/gnttab.h (revision fb2971ccd2bab42f5406f919812ceb8e014773ea)
1 /******************************************************************************
2  * gnttab.h
3  *
4  * Two sets of functionality:
5  * 1. Granting foreign access to our memory reservation.
6  * 2. Accessing others' memory reservations via grant references.
7  * (i.e., mechanisms for both sender and recipient of grant references)
8  *
9  * Copyright (c) 2004-2005, K A Fraser
10  * Copyright (c) 2005, Christopher Clark
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License version 2
14  * as published by the Free Software Foundation; or, when distributed
15  * separately from the Linux kernel or incorporated into other
16  * software packages, subject to the following license:
17  *
18  * Permission is hereby granted, free of charge, to any person obtaining a copy
19  * of this source file (the "Software"), to deal in the Software without
20  * restriction, including without limitation the rights to use, copy, modify,
21  * merge, publish, distribute, sublicense, and/or sell copies of the Software,
22  * and to permit persons to whom the Software is furnished to do so, subject to
23  * the following conditions:
24  *
25  * The above copyright notice and this permission notice shall be included in
26  * all copies or substantial portions of the Software.
27  *
28  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
29  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
30  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
31  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
32  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
33  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
34  * IN THE SOFTWARE.
35  */
36 
37 #ifndef __ASM_GNTTAB_H__
38 
39 #include <xen/interface/grant_table.h>
40 
41 #include <xen/hypervisor.h>
42 #include <xen/interface/grant_table.h>
43 #include <machine/xen/xen-os.h>
44 #include <xen/features.h>
45 
46 #define GNTTAB_LIST_END GRANT_REF_INVALID
47 
48 struct gnttab_free_callback {
49 	struct gnttab_free_callback *next;
50 	void (*fn)(void *);
51 	void *arg;
52 	uint16_t count;
53 };
54 
55 int gnttab_init(void);
56 
57 /*
58  * Allocate a grant table reference and return it in *result. Returns
59  * zero on success or errno on error.
60  */
61 int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
62     int flags, grant_ref_t *result);
63 
64 /*
65  * End access through the given grant reference, iff the grant entry is no
66  * longer in use.  Return 1 if the grant entry was freed, 0 if it is still in
67  * use.
68  */
69 int gnttab_end_foreign_access_ref(grant_ref_t ref);
70 
71 /*
72  * Eventually end access through the given grant reference, and once that
73  * access has been ended, free the given page too.  Access will be ended
74  * immediately iff the grant entry is not in use, otherwise it will happen
75  * some time later.  page may be 0, in which case no freeing will occur.
76  */
77 void gnttab_end_foreign_access(grant_ref_t ref, void *page);
78 
79 /*
80  * Eventually end access through the given array of grant references.
81  * Access will be ended immediately iff the grant entry is not in use,
82  * otherwise it will happen some time later
83  */
84 void gnttab_end_foreign_access_references(u_int count, grant_ref_t *refs);
85 
86 int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn, grant_ref_t *result);
87 
88 unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref);
89 unsigned long gnttab_end_foreign_transfer(grant_ref_t ref);
90 
91 int gnttab_query_foreign_access(grant_ref_t ref);
92 
93 /*
94  * operations on reserved batches of grant references
95  */
96 int gnttab_alloc_grant_references(uint16_t count, grant_ref_t *pprivate_head);
97 
98 void gnttab_free_grant_reference(grant_ref_t ref);
99 
100 void gnttab_free_grant_references(grant_ref_t head);
101 
102 int gnttab_empty_grant_references(const grant_ref_t *pprivate_head);
103 
104 int gnttab_claim_grant_reference(grant_ref_t *pprivate_head);
105 
106 void gnttab_release_grant_reference(grant_ref_t *private_head,
107 				    grant_ref_t release);
108 
109 void gnttab_request_free_callback(struct gnttab_free_callback *callback,
110 				  void (*fn)(void *), void *arg, uint16_t count);
111 void gnttab_cancel_free_callback(struct gnttab_free_callback *callback);
112 
113 void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
114 				     unsigned long frame, int flags);
115 
116 void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid,
117 				       unsigned long pfn);
118 
119 int gnttab_suspend(void);
120 int gnttab_resume(void);
121 
122 #if 0
123 
124 #include <xen/features.h>
125 
126 static inline void
127 gnttab_set_map_op(struct gnttab_map_grant_ref *map, vm_paddr_t addr,
128 		  uint32_t flags, grant_ref_t ref, domid_t domid)
129 {
130 	if (flags & GNTMAP_contains_pte)
131 		map->host_addr = addr;
132 	else if (xen_feature(XENFEAT_auto_translated_physmap))
133 		map->host_addr = vtophys(addr);
134 	else
135 		map->host_addr = addr;
136 
137 	map->flags = flags;
138 	map->ref = ref;
139 	map->dom = domid;
140 }
141 
142 static inline void
143 gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, vm_paddr_t addr,
144 		    uint32_t flags, grant_handle_t handle)
145 {
146 	if (flags & GNTMAP_contains_pte)
147 		unmap->host_addr = addr;
148 	else if (xen_feature(XENFEAT_auto_translated_physmap))
149 		unmap->host_addr = vtophys(addr);
150 	else
151 		unmap->host_addr = addr;
152 
153 	unmap->handle = handle;
154 	unmap->dev_bus_addr = 0;
155 }
156 
157 static inline void
158 gnttab_set_replace_op(struct gnttab_unmap_and_replace *unmap, vm_paddr_t addr,
159 		      vm_paddr_t new_addr, grant_handle_t handle)
160 {
161 	if (xen_feature(XENFEAT_auto_translated_physmap)) {
162 		unmap->host_addr = vtophys(addr);
163 		unmap->new_addr = vtophys(new_addr);
164 	} else {
165 		unmap->host_addr = addr;
166 		unmap->new_addr = new_addr;
167 	}
168 
169 	unmap->handle = handle;
170 }
171 #endif
172 
173 #endif /* __ASM_GNTTAB_H__ */
174