Avoid beyond bounds copy while caching ACL
[zen-stable.git] / include / xen / grant_table.h
blob15f8a00ff003953639a4caba0e97109b8db06b36
1 /******************************************************************************
2 * grant_table.h
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)
9 * Copyright (c) 2004-2005, K A Fraser
10 * Copyright (c) 2005, Christopher Clark
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:
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:
25 * The above copyright notice and this permission notice shall be included in
26 * all copies or substantial portions of the Software.
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.
37 #ifndef __ASM_GNTTAB_H__
38 #define __ASM_GNTTAB_H__
40 #include <asm/page.h>
42 #include <xen/interface/xen.h>
43 #include <xen/interface/grant_table.h>
45 #include <asm/xen/hypervisor.h>
47 #include <xen/features.h>
49 /* NR_GRANT_FRAMES must be less than or equal to that configured in Xen */
50 #define NR_GRANT_FRAMES 4
52 struct gnttab_free_callback {
53 struct gnttab_free_callback *next;
54 void (*fn)(void *);
55 void *arg;
56 u16 count;
59 int gnttab_init(void);
60 int gnttab_suspend(void);
61 int gnttab_resume(void);
63 int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
64 int readonly);
65 int gnttab_grant_foreign_access_subpage(domid_t domid, unsigned long frame,
66 int flags, unsigned page_off,
67 unsigned length);
68 int gnttab_grant_foreign_access_trans(domid_t domid, int flags,
69 domid_t trans_domid,
70 grant_ref_t trans_gref);
73 * Are sub-page grants available on this version of Xen? Returns true if they
74 * are, and false if they're not.
76 bool gnttab_subpage_grants_available(void);
79 * Are transitive grants available on this version of Xen? Returns true if they
80 * are, and false if they're not.
82 bool gnttab_trans_grants_available(void);
85 * End access through the given grant reference, iff the grant entry is no
86 * longer in use. Return 1 if the grant entry was freed, 0 if it is still in
87 * use.
89 int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly);
92 * Eventually end access through the given grant reference, and once that
93 * access has been ended, free the given page too. Access will be ended
94 * immediately iff the grant entry is not in use, otherwise it will happen
95 * some time later. page may be 0, in which case no freeing will occur.
97 void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
98 unsigned long page);
100 int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn);
102 unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref);
103 unsigned long gnttab_end_foreign_transfer(grant_ref_t ref);
105 int gnttab_query_foreign_access(grant_ref_t ref);
108 * operations on reserved batches of grant references
110 int gnttab_alloc_grant_references(u16 count, grant_ref_t *pprivate_head);
112 void gnttab_free_grant_reference(grant_ref_t ref);
114 void gnttab_free_grant_references(grant_ref_t head);
116 int gnttab_empty_grant_references(const grant_ref_t *pprivate_head);
118 int gnttab_claim_grant_reference(grant_ref_t *pprivate_head);
120 void gnttab_release_grant_reference(grant_ref_t *private_head,
121 grant_ref_t release);
123 void gnttab_request_free_callback(struct gnttab_free_callback *callback,
124 void (*fn)(void *), void *arg, u16 count);
125 void gnttab_cancel_free_callback(struct gnttab_free_callback *callback);
127 void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
128 unsigned long frame, int readonly);
129 int gnttab_grant_foreign_access_subpage_ref(grant_ref_t ref, domid_t domid,
130 unsigned long frame, int flags,
131 unsigned page_off,
132 unsigned length);
133 int gnttab_grant_foreign_access_trans_ref(grant_ref_t ref, domid_t domid,
134 int flags, domid_t trans_domid,
135 grant_ref_t trans_gref);
137 void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid,
138 unsigned long pfn);
140 static inline void
141 gnttab_set_map_op(struct gnttab_map_grant_ref *map, phys_addr_t addr,
142 uint32_t flags, grant_ref_t ref, domid_t domid)
144 if (flags & GNTMAP_contains_pte)
145 map->host_addr = addr;
146 else if (xen_feature(XENFEAT_auto_translated_physmap))
147 map->host_addr = __pa(addr);
148 else
149 map->host_addr = addr;
151 map->flags = flags;
152 map->ref = ref;
153 map->dom = domid;
156 static inline void
157 gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, phys_addr_t addr,
158 uint32_t flags, grant_handle_t handle)
160 if (flags & GNTMAP_contains_pte)
161 unmap->host_addr = addr;
162 else if (xen_feature(XENFEAT_auto_translated_physmap))
163 unmap->host_addr = __pa(addr);
164 else
165 unmap->host_addr = addr;
167 unmap->handle = handle;
168 unmap->dev_bus_addr = 0;
171 int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
172 unsigned long max_nr_gframes,
173 void **__shared);
174 int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes,
175 unsigned long max_nr_gframes,
176 grant_status_t **__shared);
177 void arch_gnttab_unmap(void *shared, unsigned long nr_gframes);
179 extern unsigned long xen_hvm_resume_frames;
180 unsigned int gnttab_max_grant_frames(void);
182 #define gnttab_map_vaddr(map) ((void *)(map.host_virt_addr))
184 int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
185 struct gnttab_map_grant_ref *kmap_ops,
186 struct page **pages, unsigned int count);
187 int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
188 struct page **pages, unsigned int count, bool clear_pte);
190 #endif /* __ASM_GNTTAB_H__ */