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 * Mach Operating System
30 * Copyright (c) 1987 Carnegie-Mellon University
31 * All rights reserved.  The CMU software License Agreement specifies
32 * the terms and conditions for use and redistribution.
33 */
34/*
35 *	File:	vm_pager.h
36 *	Author:	Avadis Tevanian, Jr., Michael Wayne Young
37 *
38 *	Copyright (C) 1986, Avadis Tevanian, Jr., Michael Wayne Young
39 *	Copyright (C) 1985, Avadis Tevanian, Jr., Michael Wayne Young
40 *
41 *	Pager routine interface definition
42 */
43
44#ifndef	_VM_PAGER_
45#define	_VM_PAGER_
46
47#include <mach/boolean.h>
48
49struct	pager_struct {
50	boolean_t	is_device;
51};
52typedef	struct pager_struct	*vm_pager_t;
53#define	vm_pager_null		((vm_pager_t) 0)
54
55#define	PAGER_SUCCESS		0  /* page read or written */
56#define	PAGER_ABSENT		1  /* pager does not have page */
57#define	PAGER_ERROR		2  /* pager unable to read or write page */
58
59#ifdef	KERNEL
60typedef	int		pager_return_t;
61
62extern vm_pager_t		vm_pager_allocate(void);
63extern void				vm_pager_deallocate(void);
64extern pager_return_t	vm_pager_get(void);
65extern pager_return_t	vm_pager_put(void);
66extern boolean_t		vm_pager_has_page(void);
67#endif	/* KERNEL */
68
69#endif	/* _VM_PAGER_ */
70