1/*
2 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
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.
14 *
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
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
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/vm_types.h>
64#include <mach/machine/vm_types.h>
65
66/*
67 *	External page management hint technology
68 *
69 *	The data structure exported by this module maintains
70 *	a (potentially incomplete) map of the pages written
71 *	to external storage for a range of virtual memory.
72 */
73
74typedef char	*vm_external_map_t;
75#define	VM_EXTERNAL_NULL	((char *) 0)
76
77/*
78 *	The states that may be recorded for a page of external storage.
79 */
80
81typedef int	vm_external_state_t;
82#define	VM_EXTERNAL_STATE_EXISTS		1
83#define	VM_EXTERNAL_STATE_UNKNOWN		2
84#define	VM_EXTERNAL_STATE_ABSENT		3
85
86/*
87 * Useful macros
88 */
89#define stob(s)	((atop_64((s)) + 07) >> 3)
90
91/*
92 *	Routines exported by this module.
93 */
94					/* Initialize the module */
95extern void			vm_external_module_initialize(void);
96
97
98extern vm_external_map_t	vm_external_create(
99					/* Create a vm_external_map_t */
100					vm_object_size_t	size);
101
102extern void			vm_external_destroy(
103					/* Destroy one */
104					vm_external_map_t	map,
105					vm_object_size_t	size);
106
107extern vm_object_size_t		vm_external_map_size(
108					/* Return size of map in bytes */
109					vm_object_size_t	size);
110
111extern void			vm_external_copy(
112					/* Copy one into another */
113					vm_external_map_t	old_map,
114					vm_object_size_t	old_size,
115					vm_external_map_t	new_map);
116
117extern void			vm_external_state_set(
118					/* Set state of a page to
119					 * VM_EXTERNAL_STATE_EXISTS */
120					vm_external_map_t	map,
121					vm_object_offset_t	offset);
122
123extern void			vm_external_state_clr(
124					/* clear page state
125					 */
126					vm_external_map_t	map,
127					vm_object_offset_t	offset);
128
129#define	vm_external_state_get(map, offset)			  	\
130			(((map) != VM_EXTERNAL_NULL) ? 			\
131			  _vm_external_state_get((map), (offset)) :	\
132			  VM_EXTERNAL_STATE_UNKNOWN)
133					/* Retrieve the state for a
134					 * given page, if known.  */
135
136extern vm_external_state_t	_vm_external_state_get(
137					/* HIDDEN routine */
138					vm_external_map_t	map,
139					vm_object_offset_t	offset);
140
141boolean_t			vm_external_within(
142					/* Check if new object size
143					 * fits in current map */
144					vm_object_size_t	new_size,
145					vm_object_size_t	old_size);
146
147#endif	/* VM_VM_EXTERNAL_H_ */
148