xref: /freebsd/sys/vm/vm_pager.h (revision e627b39baccd1ec9129690167cf5e6d860509655)
1 /*
2  * Copyright (c) 1990 University of Utah.
3  * Copyright (c) 1991, 1993
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * the Systems Programming Group of the University of Utah Computer
8  * Science Department.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  *	@(#)vm_pager.h	8.4 (Berkeley) 1/12/94
39  * $Id: vm_pager.h,v 1.10 1995/11/20 12:19:16 phk Exp $
40  */
41 
42 /*
43  * Pager routine interface definition.
44  */
45 
46 #ifndef	_VM_PAGER_
47 #define	_VM_PAGER_
48 
49 TAILQ_HEAD(pagerlst, vm_object);
50 
51 struct pagerops {
52 	void (*pgo_init) __P((void));		/* Initialize pager. */
53 	vm_object_t (*pgo_alloc) __P((void *, vm_size_t, vm_prot_t, vm_ooffset_t));	/* Allocate pager. */
54 	void (*pgo_dealloc) __P((vm_object_t));	/* Disassociate. */
55 	int (*pgo_getpages) __P((vm_object_t, vm_page_t *, int, int));	/* Get (read) page. */
56 	int (*pgo_putpages) __P((vm_object_t, vm_page_t *, int, boolean_t, int *)); /* Put (write) page. */
57 	boolean_t (*pgo_haspage) __P((vm_object_t, vm_pindex_t, int *, int *)); /* Does pager have page? */
58 	void (*pgo_sync) __P((void));
59 };
60 
61 /*
62  * get/put return values
63  * OK	 operation was successful
64  * BAD	 specified data was out of the accepted range
65  * FAIL	 specified data was in range, but doesn't exist
66  * PEND	 operations was initiated but not completed
67  * ERROR error while accessing data that is in range and exists
68  * AGAIN temporary resource shortage prevented operation from happening
69  */
70 #define	VM_PAGER_OK	0
71 #define	VM_PAGER_BAD	1
72 #define	VM_PAGER_FAIL	2
73 #define	VM_PAGER_PEND	3
74 #define	VM_PAGER_ERROR	4
75 #define VM_PAGER_AGAIN	5
76 
77 #ifdef KERNEL
78 extern vm_map_t pager_map;
79 extern int pager_map_size;
80 
81 vm_object_t vm_pager_allocate __P((objtype_t, void *, vm_size_t, vm_prot_t, vm_ooffset_t));
82 void vm_pager_bufferinit __P((void));
83 void vm_pager_deallocate __P((vm_object_t));
84 int vm_pager_get_pages __P((vm_object_t, vm_page_t *, int, int));
85 boolean_t vm_pager_has_page __P((vm_object_t, vm_pindex_t, int *, int *));
86 void vm_pager_init __P((void));
87 vm_object_t vm_pager_object_lookup __P((struct pagerlst *, void *));
88 vm_offset_t vm_pager_map_pages __P((vm_page_t *, int, boolean_t));
89 vm_offset_t vm_pager_map_page __P((vm_page_t));
90 int vm_pager_put_pages __P((vm_object_t, vm_page_t *, int, boolean_t, int *));
91 void vm_pager_sync __P((void));
92 void vm_pager_unmap_pages __P((vm_offset_t, int));
93 void vm_pager_unmap_page __P((vm_offset_t));
94 #endif
95 
96 #endif				/* _VM_PAGER_ */
97