summaryrefslogtreecommitdiff
path: root/sys/vm/vm_pager.h
blob: 53faf42aaabe2af61baf5cad368e81d4209e4f1e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
/*	$OpenBSD: vm_pager.h,v 1.3 1997/10/06 15:28:57 csapuntz Exp $	*/
/*	$NetBSD: vm_pager.h,v 1.10 1995/03/26 20:39:15 jtc Exp $	*/

/*
 * Copyright (c) 1990 University of Utah.
 * Copyright (c) 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * the Systems Programming Group of the University of Utah Computer
 * Science Department.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)vm_pager.h	8.5 (Berkeley) 7/7/94
 */

/*
 * Pager routine interface definition.
 * For BSD we use a cleaner version of the internal pager interface.
 */

#ifndef	_VM_PAGER_
#define	_VM_PAGER_

TAILQ_HEAD(pagerlst, pager_struct);

struct	pager_struct {
	TAILQ_ENTRY(pager_struct) pg_list;	/* links for list management */
	caddr_t			  pg_handle;	/* ext. handle (vp, dev, fp) */
	int			  pg_type;	/* type of pager */
	int			  pg_flags;	/* flags */
	struct pagerops		  *pg_ops;	/* pager operations */
	void			  *pg_data;	/* private pager data */
};

/* pager types */
#define PG_DFLT		-1
#define	PG_SWAP		0
#define	PG_VNODE	1
#define PG_DEVICE	2

/* flags */
#define PG_CLUSTERGET	1
#define PG_CLUSTERPUT	2

struct	pagerops {
	void		(*pgo_init)		/* Initialize pager. */
			    __P((void));
	vm_pager_t	(*pgo_alloc)		/* Allocate pager. */
			    __P((caddr_t, vm_size_t, vm_prot_t, vm_offset_t));
	void		(*pgo_dealloc)		/* Disassociate. */
			    __P((vm_pager_t));
	int		(*pgo_getpages)		/* Get (read) pages. */
			    __P((vm_pager_t, vm_page_t *, int, boolean_t));
	int		(*pgo_putpages)		/* Put (write) pages. */
			    __P((vm_pager_t, vm_page_t *, int, boolean_t));
	boolean_t  	(*pgo_haspage)		/* Does pager have page? */
			    __P((vm_pager_t, vm_offset_t));
	void		(*pgo_cluster)		/* Return range of cluster. */
			    __P((vm_pager_t, vm_offset_t,
				 vm_offset_t *, vm_offset_t *));
	/*
	 *	The following are an extension to the original Mach pager
	 *	interface first seen in BSD/OS 2.1 (at least as far as I am
	 *	aware).  As compatibility is a good thing (tm) I choose to
	 *	use that interface extension instead of coming up with one
	 *	of my own (the interface must be extended to make the
	 *	object collapse operation work in the presense of pagers).
	 *	-- Niklas Hallqvist (niklas@appli.se).
	 */
	int		(*pgo_remove)		/* Don't manage range anymore */
			    __P((vm_pager_t, vm_offset_t, vm_offset_t));
	vm_offset_t	(*pgo_next)		/* Find next page in pager. */
			    __P((vm_pager_t, vm_offset_t));
	int		(*pgo_count)		/* How many pages in pager? */
			    __P((vm_pager_t));
};

/*
 * get/put return values
 * OK	 operation was successful
 * BAD	 specified data was out of the accepted range
 * FAIL	 specified data was in range, but doesn't exist
 * PEND	 operations was initiated but not completed
 * ERROR error while accessing data that is in range and exists
 * AGAIN temporary resource shortage prevented operation from happening
 */
#define	VM_PAGER_OK	0
#define	VM_PAGER_BAD	1
#define	VM_PAGER_FAIL	2
#define	VM_PAGER_PEND	3
#define	VM_PAGER_ERROR	4
#define VM_PAGER_AGAIN	5

#ifdef _KERNEL
extern struct pagerops *dfltpagerops;

vm_pager_t	vm_pager_allocate
		    __P((int, caddr_t, vm_size_t, vm_prot_t, vm_offset_t));
vm_page_t	vm_pager_atop __P((vm_offset_t));
void		vm_pager_cluster
		    __P((vm_pager_t, vm_offset_t,
			 vm_offset_t *, vm_offset_t *));
void		vm_pager_clusternull
		    __P((vm_pager_t, vm_offset_t,
			 vm_offset_t *, vm_offset_t *));
void		vm_pager_deallocate __P((vm_pager_t));
int		vm_pager_remove
		    __P((vm_pager_t, vm_offset_t, vm_offset_t));
int		vm_pager_count __P((vm_pager_t));
vm_offset_t	vm_pager_next __P((vm_pager_t, vm_offset_t));
int		vm_pager_get_pages
		    __P((vm_pager_t, vm_page_t *, int, boolean_t));
boolean_t	vm_pager_has_page __P((vm_pager_t, vm_offset_t));
void		vm_pager_init __P((void));
vm_pager_t	vm_pager_lookup __P((struct pagerlst *, caddr_t));
vm_offset_t	vm_pager_map_pages __P((vm_page_t *, int, boolean_t));
int		vm_pager_put_pages
		    __P((vm_pager_t, vm_page_t *, int, boolean_t));
void		vm_pager_sync __P((void));
void		vm_pager_unmap_pages __P((vm_offset_t, int));

#define vm_pager_cancluster(p, b)	((p)->pg_flags & (b))

/*
 * XXX compat with old interface
 */
int		vm_pager_get __P((vm_pager_t, vm_page_t, boolean_t));
int		vm_pager_put __P((vm_pager_t, vm_page_t, boolean_t));
#endif

#endif	/* _VM_PAGER_ */