xref: /freebsd/sys/xen/gnttab.h (revision 93e779a26c651610ac6e7986d67ecc9ed2cadcbf)
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 /*
55  * Allocate a grant table reference and return it in *result. Returns
56  * zero on success or errno on error.
57  */
58 int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
59     int flags, grant_ref_t *result);
60 
61 /*
62  * End access through the given grant reference, iff the grant entry is no
63  * longer in use.  Return 1 if the grant entry was freed, 0 if it is still in
64  * use.
65  */
66 int gnttab_end_foreign_access_ref(grant_ref_t ref);
67 
68 /*
69  * Eventually end access through the given grant reference, and once that
70  * access has been ended, free the given page too.  Access will be ended
71  * immediately iff the grant entry is not in use, otherwise it will happen
72  * some time later.  page may be 0, in which case no freeing will occur.
73  */
74 void gnttab_end_foreign_access(grant_ref_t ref, void *page);
75 
76 /*
77  * Eventually end access through the given array of grant references.
78  * Access will be ended immediately iff the grant entry is not in use,
79  * otherwise it will happen some time later
80  */
81 void gnttab_end_foreign_access_references(u_int count, grant_ref_t *refs);
82 
83 int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn, grant_ref_t *result);
84 
85 unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref);
86 unsigned long gnttab_end_foreign_transfer(grant_ref_t ref);
87 
88 int gnttab_query_foreign_access(grant_ref_t ref);
89 
90 /*
91  * operations on reserved batches of grant references
92  */
93 int gnttab_alloc_grant_references(uint16_t count, grant_ref_t *pprivate_head);
94 
95 void gnttab_free_grant_reference(grant_ref_t ref);
96 
97 void gnttab_free_grant_references(grant_ref_t head);
98 
99 int gnttab_empty_grant_references(const grant_ref_t *pprivate_head);
100 
101 int gnttab_claim_grant_reference(grant_ref_t *pprivate_head);
102 
103 void gnttab_release_grant_reference(grant_ref_t *private_head,
104 				    grant_ref_t release);
105 
106 void gnttab_request_free_callback(struct gnttab_free_callback *callback,
107 				  void (*fn)(void *), void *arg, uint16_t count);
108 void gnttab_cancel_free_callback(struct gnttab_free_callback *callback);
109 
110 void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
111 				     unsigned long frame, int flags);
112 
113 void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid,
114 				       unsigned long pfn);
115 
116 int gnttab_suspend(void);
117 int gnttab_resume(device_t);
118 
119 #if 0
120 
121 #include <xen/features.h>
122 
123 static inline void
124 gnttab_set_map_op(struct gnttab_map_grant_ref *map, vm_paddr_t addr,
125 		  uint32_t flags, grant_ref_t ref, domid_t domid)
126 {
127 	if (flags & GNTMAP_contains_pte)
128 		map->host_addr = addr;
129 	else
130 		map->host_addr = vtophys(addr);
131 
132 	map->flags = flags;
133 	map->ref = ref;
134 	map->dom = domid;
135 }
136 
137 static inline void
138 gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, vm_paddr_t addr,
139 		    uint32_t flags, grant_handle_t handle)
140 {
141 	if (flags & GNTMAP_contains_pte)
142 		unmap->host_addr = addr;
143 	else
144 		unmap->host_addr = vtophys(addr);
145 
146 	unmap->handle = handle;
147 	unmap->dev_bus_addr = 0;
148 }
149 
150 static inline void
151 gnttab_set_replace_op(struct gnttab_unmap_and_replace *unmap, vm_paddr_t addr,
152 		      vm_paddr_t new_addr, grant_handle_t handle)
153 {
154 	unmap->host_addr = vtophys(addr);
155 	unmap->new_addr = vtophys(new_addr);
156 
157 	unmap->handle = handle;
158 }
159 #endif
160 
161 #endif /* __ASM_GNTTAB_H__ */
162