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
47struct gnttab_free_callback {
48	struct gnttab_free_callback *next;
49	void (*fn)(void *);
50	void *arg;
51	uint16_t count;
52};
53
54int 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 */
60int 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 */
68int 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 */
76void 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 */
83void gnttab_end_foreign_access_references(u_int count, grant_ref_t *refs);
84
85int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn, grant_ref_t *result);
86
87unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref);
88unsigned long gnttab_end_foreign_transfer(grant_ref_t ref);
89
90int gnttab_query_foreign_access(grant_ref_t ref);
91
92/*
93 * operations on reserved batches of grant references
94 */
95int gnttab_alloc_grant_references(uint16_t count, grant_ref_t *pprivate_head);
96
97void gnttab_free_grant_reference(grant_ref_t ref);
98
99void gnttab_free_grant_references(grant_ref_t head);
100
101int gnttab_empty_grant_references(const grant_ref_t *pprivate_head);
102
103int gnttab_claim_grant_reference(grant_ref_t *pprivate_head);
104
105void gnttab_release_grant_reference(grant_ref_t *private_head,
106				    grant_ref_t release);
107
108void gnttab_request_free_callback(struct gnttab_free_callback *callback,
109				  void (*fn)(void *), void *arg, uint16_t count);
110void gnttab_cancel_free_callback(struct gnttab_free_callback *callback);
111
112void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
113				     unsigned long frame, int flags);
114
115void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid,
116				       unsigned long pfn);
117
118int gnttab_suspend(void);
119int gnttab_resume(void);
120
121#if 0
122
123#include <xen/features.h>
124
125static inline void
126gnttab_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
141static inline void
142gnttab_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
156static inline void
157gnttab_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