vm_pager.h revision 7090
1
2/*
3 * Copyright (c) 1990 University of Utah.
4 * Copyright (c) 1991, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * the Systems Programming Group of the University of Utah Computer
9 * Science Department.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 *    must display the following acknowledgement:
21 *	This product includes software developed by the University of
22 *	California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 *    may be used to endorse or promote products derived from this software
25 *    without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 *	@(#)vm_pager.h	8.4 (Berkeley) 1/12/94
40 * $Id: vm_pager.h,v 1.5 1995/01/09 16:05:56 davidg Exp $
41 */
42
43/*
44 * Pager routine interface definition.
45 * For BSD we use a cleaner version of the internal pager interface.
46 */
47
48#ifndef	_VM_PAGER_
49#define	_VM_PAGER_
50
51TAILQ_HEAD(pagerlst, pager_struct);
52
53struct pager_struct {
54	TAILQ_ENTRY(pager_struct) pg_list;	/* links for list management */
55	caddr_t pg_handle;		/* ext. handle (vp, dev, fp) */
56	int pg_type;			/* type of pager */
57	struct pagerops *pg_ops;	/* pager operations */
58	void *pg_data;			/* private pager data */
59};
60
61/* pager types */
62#define PG_DFLT		-1
63#define	PG_SWAP		0
64#define	PG_VNODE	1
65#define PG_DEVICE	2
66
67/* flags */
68#define PG_CLUSTERGET	1
69#define PG_CLUSTERPUT	2
70
71struct pagerops {
72	void (*pgo_init) __P((void));		/* Initialize pager. */
73	vm_pager_t(*pgo_alloc) __P((caddr_t, vm_size_t, vm_prot_t, vm_offset_t));	/* Allocate pager. */
74	void (*pgo_dealloc) __P((vm_pager_t));	/* Disassociate. */
75	int (*pgo_getpage) __P((vm_pager_t, vm_page_t, boolean_t));
76	int (*pgo_getpages) __P((vm_pager_t, vm_page_t *, int, int, boolean_t));	/* Get (read) page. */
77	int (*pgo_putpage) __P((vm_pager_t, vm_page_t, boolean_t));
78	int (*pgo_putpages) __P((vm_pager_t, vm_page_t *, int, boolean_t, int *)); /* Put (write) page. */
79	boolean_t(*pgo_haspage) __P((vm_pager_t, vm_offset_t)); /* Does pager have page? */
80};
81
82#define	VM_PAGER_ALLOC(h, s, p, o)		(*(pg)->pg_ops->pgo_alloc)(h, s, p, o)
83#define	VM_PAGER_DEALLOC(pg)		(*(pg)->pg_ops->pgo_dealloc)(pg)
84#define	VM_PAGER_GET(pg, m, s)		(*(pg)->pg_ops->pgo_getpage)(pg, m, s)
85#define	VM_PAGER_GET_MULTI(pg, m, c, r, s)	(*(pg)->pg_ops->pgo_getpages)(pg, m, c, r, s)
86#define	VM_PAGER_PUT(pg, m, s)		(*(pg)->pg_ops->pgo_putpage)(pg, m, s)
87#define	VM_PAGER_PUT_MULTI(pg, m, c, s, rtval)		(*(pg)->pg_ops->pgo_putpages)(pg, m, c, s, rtval)
88#define	VM_PAGER_HASPAGE(pg, o)		(*(pg)->pg_ops->pgo_haspage)(pg, o)
89
90/*
91 * get/put return values
92 * OK	 operation was successful
93 * BAD	 specified data was out of the accepted range
94 * FAIL	 specified data was in range, but doesn't exist
95 * PEND	 operations was initiated but not completed
96 * ERROR error while accessing data that is in range and exists
97 * AGAIN temporary resource shortage prevented operation from happening
98 */
99#define	VM_PAGER_OK	0
100#define	VM_PAGER_BAD	1
101#define	VM_PAGER_FAIL	2
102#define	VM_PAGER_PEND	3
103#define	VM_PAGER_ERROR	4
104#define VM_PAGER_AGAIN	5
105
106#ifdef KERNEL
107extern struct pagerops *dfltpagerops;
108
109vm_pager_t vm_pager_allocate __P((int, caddr_t, vm_size_t, vm_prot_t, vm_offset_t));
110vm_page_t vm_pager_atop __P((vm_offset_t));
111void vm_pager_bufferinit __P((void));
112void vm_pager_deallocate __P((vm_pager_t));
113int vm_pager_get_pages __P((vm_pager_t, vm_page_t *, int, int, boolean_t));
114boolean_t vm_pager_has_page __P((vm_pager_t, vm_offset_t));
115void vm_pager_init __P((void));
116vm_pager_t vm_pager_lookup __P((struct pagerlst *, caddr_t));
117vm_offset_t vm_pager_map_pages __P((vm_page_t *, int, boolean_t));
118vm_offset_t vm_pager_map_page __P((vm_page_t));
119int vm_pager_put_pages __P((vm_pager_t, vm_page_t *, int, boolean_t, int *));
120void vm_pager_sync __P((void));
121void vm_pager_unmap_pages __P((vm_offset_t, int));
122void vm_pager_unmap_page __P((vm_offset_t));
123
124/*
125 * XXX compat with old interface
126 */
127#define vm_pager_get(p, m, s) \
128({ \
129	vm_page_t ml[1]; \
130	ml[0] = (m); \
131	vm_pager_get_pages(p, ml, 1, 0, s); \
132})
133
134#define vm_pager_put(p, m, s) \
135({ \
136	int rtval; \
137	vm_page_t ml[1]; \
138	ml[0] = (m); \
139	vm_pager_put_pages(p, ml, 1, s, &rtval); \
140	rtval; \
141})
142#endif
143
144#endif				/* _VM_PAGER_ */
145