xref: /freebsd/sys/xen/gnttab.h (revision 830940567b49bb0c08dfaed40418999e76616909)
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 struct gnttab_free_callback {
47 	struct gnttab_free_callback *next;
48 	void (*fn)(void *);
49 	void *arg;
50 	uint16_t count;
51 };
52 
53 int gnttab_init(void);
54 
55 /*
56  * Allocate a grant table reference and return it in *result. Returns
57  * zero on success or errno on error.
58  */
59 int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
60     int flags, grant_ref_t *result);
61 
62 /*
63  * End access through the given grant reference, iff the grant entry is no
64  * longer in use.  Return 1 if the grant entry was freed, 0 if it is still in
65  * use.
66  */
67 int gnttab_end_foreign_access_ref(grant_ref_t ref);
68 
69 /*
70  * Eventually end access through the given grant reference, and once that
71  * access has been ended, free the given page too.  Access will be ended
72  * immediately iff the grant entry is not in use, otherwise it will happen
73  * some time later.  page may be 0, in which case no freeing will occur.
74  */
75 void gnttab_end_foreign_access(grant_ref_t ref, void *page);
76 
77 int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn, grant_ref_t *result);
78 
79 unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref);
80 unsigned long gnttab_end_foreign_transfer(grant_ref_t ref);
81 
82 int gnttab_query_foreign_access(grant_ref_t ref);
83 
84 /*
85  * operations on reserved batches of grant references
86  */
87 int gnttab_alloc_grant_references(uint16_t count, grant_ref_t *pprivate_head);
88 
89 void gnttab_free_grant_reference(grant_ref_t ref);
90 
91 void gnttab_free_grant_references(grant_ref_t head);
92 
93 int gnttab_empty_grant_references(const grant_ref_t *pprivate_head);
94 
95 int gnttab_claim_grant_reference(grant_ref_t *pprivate_head);
96 
97 void gnttab_release_grant_reference(grant_ref_t *private_head,
98 				    grant_ref_t release);
99 
100 void gnttab_request_free_callback(struct gnttab_free_callback *callback,
101 				  void (*fn)(void *), void *arg, uint16_t count);
102 void gnttab_cancel_free_callback(struct gnttab_free_callback *callback);
103 
104 void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
105 				     unsigned long frame, int flags);
106 
107 void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid,
108 				       unsigned long pfn);
109 
110 int gnttab_suspend(void);
111 int gnttab_resume(void);
112 
113 #if 0
114 
115 #include <xen/features.h>
116 
117 static inline void
118 gnttab_set_map_op(struct gnttab_map_grant_ref *map, vm_paddr_t addr,
119 		  uint32_t flags, grant_ref_t ref, domid_t domid)
120 {
121 	if (flags & GNTMAP_contains_pte)
122 		map->host_addr = addr;
123 	else if (xen_feature(XENFEAT_auto_translated_physmap))
124 		map->host_addr = vtophys(addr);
125 	else
126 		map->host_addr = addr;
127 
128 	map->flags = flags;
129 	map->ref = ref;
130 	map->dom = domid;
131 }
132 
133 static inline void
134 gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, vm_paddr_t addr,
135 		    uint32_t flags, grant_handle_t handle)
136 {
137 	if (flags & GNTMAP_contains_pte)
138 		unmap->host_addr = addr;
139 	else if (xen_feature(XENFEAT_auto_translated_physmap))
140 		unmap->host_addr = vtophys(addr);
141 	else
142 		unmap->host_addr = addr;
143 
144 	unmap->handle = handle;
145 	unmap->dev_bus_addr = 0;
146 }
147 
148 static inline void
149 gnttab_set_replace_op(struct gnttab_unmap_and_replace *unmap, vm_paddr_t addr,
150 		      vm_paddr_t new_addr, grant_handle_t handle)
151 {
152 	if (xen_feature(XENFEAT_auto_translated_physmap)) {
153 		unmap->host_addr = vtophys(addr);
154 		unmap->new_addr = vtophys(new_addr);
155 	} else {
156 		unmap->host_addr = addr;
157 		unmap->new_addr = new_addr;
158 	}
159 
160 	unmap->handle = handle;
161 }
162 #endif
163 
164 #endif /* __ASM_GNTTAB_H__ */
165