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1/*
2 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3 *
2d21ac55 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
1c79356b 5 *
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6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
8f6c56a5 14 *
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15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
8f6c56a5
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20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
8f6c56a5 25 *
2d21ac55 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
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27 */
28/*
29 * @OSF_COPYRIGHT@
30 */
31/*
32 * Mach Operating System
33 * Copyright (c) 1991,1990,1989 Carnegie Mellon University
34 * All Rights Reserved.
35 *
36 * Permission to use, copy, modify and distribute this software and its
37 * documentation is hereby granted, provided that both the copyright
38 * notice and this permission notice appear in all copies of the
39 * software, derivative works or modified versions, and any portions
40 * thereof, and that both notices appear in supporting documentation.
41 *
42 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
43 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
44 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
45 *
46 * Carnegie Mellon requests users of this software to return to
47 *
48 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
49 * School of Computer Science
50 * Carnegie Mellon University
51 * Pittsburgh PA 15213-3890
52 *
53 * any improvements or extensions that they make and grant Carnegie Mellon
54 * the rights to redistribute these changes.
55 */
56/*
57 */
58
59#ifndef VM_VM_EXTERNAL_H_
60#define VM_VM_EXTERNAL_H_
61
62#include <mach/boolean.h>
63#include <mach/machine/vm_types.h>
64
65/*
66 * External page management hint technology
67 *
68 * The data structure exported by this module maintains
69 * a (potentially incomplete) map of the pages written
70 * to external storage for a range of virtual memory.
71 */
72
73typedef char *vm_external_map_t;
74#define VM_EXTERNAL_NULL ((char *) 0)
75
76/*
77 * The states that may be recorded for a page of external storage.
78 */
79
80typedef int vm_external_state_t;
81#define VM_EXTERNAL_STATE_EXISTS 1
82#define VM_EXTERNAL_STATE_UNKNOWN 2
83#define VM_EXTERNAL_STATE_ABSENT 3
84
85/*
86 * Useful macros
87 */
55e303ae 88#define stob(s) ((atop_32((s)) + 07) >> 3)
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89
90/*
91 * Routines exported by this module.
92 */
93 /* Initialize the module */
94extern void vm_external_module_initialize(void);
95
96
97extern vm_external_map_t vm_external_create(
98 /* Create a vm_external_map_t */
99 vm_offset_t size);
100
101extern void vm_external_destroy(
102 /* Destroy one */
103 vm_external_map_t map,
104 vm_size_t size);
105
106extern vm_size_t vm_external_map_size(
107 /* Return size of map in bytes */
108 vm_offset_t size);
109
110extern void vm_external_copy(
111 /* Copy one into another */
112 vm_external_map_t old_map,
113 vm_size_t old_size,
114 vm_external_map_t new_map);
115
116extern void vm_external_state_set(
117 /* Set state of a page to
118 * VM_EXTERNAL_STATE_EXISTS */
119 vm_external_map_t map,
120 vm_offset_t offset);
121
122extern void vm_external_state_clr(
123 /* clear page state
124 */
125 vm_external_map_t map,
126 vm_offset_t offset);
127
128#define vm_external_state_get(map, offset) \
129 (((map) != VM_EXTERNAL_NULL) ? \
130 _vm_external_state_get((map), (offset)) : \
131 VM_EXTERNAL_STATE_UNKNOWN)
132 /* Retrieve the state for a
133 * given page, if known. */
134
135extern vm_external_state_t _vm_external_state_get(
136 /* HIDDEN routine */
137 vm_external_map_t map,
138 vm_offset_t offset);
139
140boolean_t vm_external_within(
141 /* Check if new object size
142 * fits in current map */
143 vm_size_t new_size,
144 vm_size_t old_size);
145#endif /* VM_VM_EXTERNAL_H_ */