xref: /freebsd/sys/xen/gnttab.h (revision 38f0b757fd84d17d0fc24739a7cda160c4516d81)
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/xen-os.h>
40 #include <xen/hypervisor.h>
41 #include <xen/features.h>
42 
43 #include <xen/interface/grant_table.h>
44 
45 #define GNTTAB_LIST_END GRANT_REF_INVALID
46 
47 struct gnttab_free_callback {
48 	struct gnttab_free_callback *next;
49 	void (*fn)(void *);
50 	void *arg;
51 	uint16_t count;
52 };
53 
54 int gnttab_init(void);
55 
56 /*
57  * Allocate a grant table reference and return it in *result. Returns
58  * zero on success or errno on error.
59  */
60 int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
61     int flags, grant_ref_t *result);
62 
63 /*
64  * End access through the given grant reference, iff the grant entry is no
65  * longer in use.  Return 1 if the grant entry was freed, 0 if it is still in
66  * use.
67  */
68 int gnttab_end_foreign_access_ref(grant_ref_t ref);
69 
70 /*
71  * Eventually end access through the given grant reference, and once that
72  * access has been ended, free the given page too.  Access will be ended
73  * immediately iff the grant entry is not in use, otherwise it will happen
74  * some time later.  page may be 0, in which case no freeing will occur.
75  */
76 void gnttab_end_foreign_access(grant_ref_t ref, void *page);
77 
78 /*
79  * Eventually end access through the given array of grant references.
80  * Access will be ended immediately iff the grant entry is not in use,
81  * otherwise it will happen some time later
82  */
83 void gnttab_end_foreign_access_references(u_int count, grant_ref_t *refs);
84 
85 int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn, grant_ref_t *result);
86 
87 unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref);
88 unsigned long gnttab_end_foreign_transfer(grant_ref_t ref);
89 
90 int gnttab_query_foreign_access(grant_ref_t ref);
91 
92 /*
93  * operations on reserved batches of grant references
94  */
95 int gnttab_alloc_grant_references(uint16_t count, grant_ref_t *pprivate_head);
96 
97 void gnttab_free_grant_reference(grant_ref_t ref);
98 
99 void gnttab_free_grant_references(grant_ref_t head);
100 
101 int gnttab_empty_grant_references(const grant_ref_t *pprivate_head);
102 
103 int gnttab_claim_grant_reference(grant_ref_t *pprivate_head);
104 
105 void gnttab_release_grant_reference(grant_ref_t *private_head,
106 				    grant_ref_t release);
107 
108 void gnttab_request_free_callback(struct gnttab_free_callback *callback,
109 				  void (*fn)(void *), void *arg, uint16_t count);
110 void gnttab_cancel_free_callback(struct gnttab_free_callback *callback);
111 
112 void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
113 				     unsigned long frame, int flags);
114 
115 void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid,
116 				       unsigned long pfn);
117 
118 int gnttab_suspend(void);
119 int gnttab_resume(void);
120 
121 #if 0
122 
123 #include <xen/features.h>
124 
125 static inline void
126 gnttab_set_map_op(struct gnttab_map_grant_ref *map, vm_paddr_t addr,
127 		  uint32_t flags, grant_ref_t ref, domid_t domid)
128 {
129 	if (flags & GNTMAP_contains_pte)
130 		map->host_addr = addr;
131 	else if (xen_feature(XENFEAT_auto_translated_physmap))
132 		map->host_addr = vtophys(addr);
133 	else
134 		map->host_addr = addr;
135 
136 	map->flags = flags;
137 	map->ref = ref;
138 	map->dom = domid;
139 }
140 
141 static inline void
142 gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, vm_paddr_t addr,
143 		    uint32_t flags, grant_handle_t handle)
144 {
145 	if (flags & GNTMAP_contains_pte)
146 		unmap->host_addr = addr;
147 	else if (xen_feature(XENFEAT_auto_translated_physmap))
148 		unmap->host_addr = vtophys(addr);
149 	else
150 		unmap->host_addr = addr;
151 
152 	unmap->handle = handle;
153 	unmap->dev_bus_addr = 0;
154 }
155 
156 static inline void
157 gnttab_set_replace_op(struct gnttab_unmap_and_replace *unmap, vm_paddr_t addr,
158 		      vm_paddr_t new_addr, grant_handle_t handle)
159 {
160 	if (xen_feature(XENFEAT_auto_translated_physmap)) {
161 		unmap->host_addr = vtophys(addr);
162 		unmap->new_addr = vtophys(new_addr);
163 	} else {
164 		unmap->host_addr = addr;
165 		unmap->new_addr = new_addr;
166 	}
167 
168 	unmap->handle = handle;
169 }
170 #endif
171 
172 #endif /* __ASM_GNTTAB_H__ */
173