xref: /freebsd/sys/xen/gnttab.h (revision 4a5216a6dc0c3ce4cf5f2d3ee8af0c3ff3402c4f)
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 <machine/xen/hypervisor.h>
40 #include <xen/interface/grant_table.h>
41 #include <machine/xen/xen-os.h>
42 #include <machine/xen/hypervisor.h>
43 #include <machine/xen/features.h>
44 
45 struct gnttab_free_callback {
46 	struct gnttab_free_callback *next;
47 	void (*fn)(void *);
48 	void *arg;
49 	uint16_t count;
50 };
51 
52 int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
53 				int flags);
54 
55 /*
56  * End access through the given grant reference, iff the grant entry is no
57  * longer in use.  Return 1 if the grant entry was freed, 0 if it is still in
58  * use.
59  */
60 int gnttab_end_foreign_access_ref(grant_ref_t ref);
61 
62 /*
63  * Eventually end access through the given grant reference, and once that
64  * access has been ended, free the given page too.  Access will be ended
65  * immediately iff the grant entry is not in use, otherwise it will happen
66  * some time later.  page may be 0, in which case no freeing will occur.
67  */
68 void gnttab_end_foreign_access(grant_ref_t ref, void *page);
69 
70 int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn);
71 
72 unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref);
73 unsigned long gnttab_end_foreign_transfer(grant_ref_t ref);
74 
75 int gnttab_query_foreign_access(grant_ref_t ref);
76 
77 /*
78  * operations on reserved batches of grant references
79  */
80 int gnttab_alloc_grant_references(uint16_t count, grant_ref_t *pprivate_head);
81 
82 void gnttab_free_grant_reference(grant_ref_t ref);
83 
84 void gnttab_free_grant_references(grant_ref_t head);
85 
86 int gnttab_empty_grant_references(const grant_ref_t *pprivate_head);
87 
88 int gnttab_claim_grant_reference(grant_ref_t *pprivate_head);
89 
90 void gnttab_release_grant_reference(grant_ref_t *private_head,
91 				    grant_ref_t release);
92 
93 void gnttab_request_free_callback(struct gnttab_free_callback *callback,
94 				  void (*fn)(void *), void *arg, uint16_t count);
95 void gnttab_cancel_free_callback(struct gnttab_free_callback *callback);
96 
97 void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
98 				     unsigned long frame, int flags);
99 
100 void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid,
101 				       unsigned long pfn);
102 
103 int gnttab_suspend(void);
104 int gnttab_resume(void);
105 
106 static inline void
107 gnttab_set_map_op(struct gnttab_map_grant_ref *map, vm_paddr_t addr,
108 		  uint32_t flags, grant_ref_t ref, domid_t domid)
109 {
110 	if (flags & GNTMAP_contains_pte)
111 		map->host_addr = addr;
112 	else if (xen_feature(XENFEAT_auto_translated_physmap))
113 		map->host_addr = vtophys(addr);
114 	else
115 		map->host_addr = addr;
116 
117 	map->flags = flags;
118 	map->ref = ref;
119 	map->dom = domid;
120 }
121 
122 static inline void
123 gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, vm_paddr_t addr,
124 		    uint32_t flags, grant_handle_t handle)
125 {
126 	if (flags & GNTMAP_contains_pte)
127 		unmap->host_addr = addr;
128 	else if (xen_feature(XENFEAT_auto_translated_physmap))
129 		unmap->host_addr = vtophys(addr);
130 	else
131 		unmap->host_addr = addr;
132 
133 	unmap->handle = handle;
134 	unmap->dev_bus_addr = 0;
135 }
136 
137 static inline void
138 gnttab_set_replace_op(struct gnttab_unmap_and_replace *unmap, vm_paddr_t addr,
139 		      vm_paddr_t new_addr, grant_handle_t handle)
140 {
141 	if (xen_feature(XENFEAT_auto_translated_physmap)) {
142 		unmap->host_addr = vtophys(addr);
143 		unmap->new_addr = vtophys(new_addr);
144 	} else {
145 		unmap->host_addr = addr;
146 		unmap->new_addr = new_addr;
147 	}
148 
149 	unmap->handle = handle;
150 }
151 
152 #endif /* __ASM_GNTTAB_H__ */
153