2 * Copyright (c) 1990 University of Utah.
3 * Copyright (c) 1991, 1993
4 * The Regents of the University of California. All rights reserved.
6 * This code is derived from software contributed to Berkeley by
7 * the Systems Programming Group of the University of Utah Computer
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
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.
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
38 * @(#)vm_pager.h 8.4 (Berkeley) 1/12/94
39 * $FreeBSD: src/sys/vm/vm_pager.h,v 1.24.2.2 2002/12/31 09:34:51 dillon Exp $
40 * $DragonFly: src/sys/vm/vm_pager.h,v 1.9 2006/12/28 21:24:02 dillon Exp $
44 * Pager routine interface definition.
47 #ifndef _VM_VM_PAGER_H_
48 #define _VM_VM_PAGER_H_
51 #include <sys/queue.h>
53 #ifndef _VM_VM_PAGE_H_
54 #include <vm/vm_page.h>
56 #ifndef _VM_VM_OBJECT_H_
57 #include <vm/vm_object.h>
64 void (*pgo_dealloc
) (vm_object_t
);
65 int (*pgo_getpage
) (vm_object_t
, vm_page_t
*, int);
66 void (*pgo_putpages
) (vm_object_t
, vm_page_t
*, int, int, int *);
67 boolean_t (*pgo_haspage
) (vm_object_t
, vm_pindex_t
);
71 * get/put return values
72 * OK operation was successful
73 * BAD specified data was out of the accepted range
74 * FAIL specified data was in range, but doesn't exist
75 * PEND operations was initiated but not completed
76 * ERROR error while accessing data that is in range and exists
77 * AGAIN temporary resource shortage prevented operation from happening
80 #define VM_PAGER_BAD 1
81 #define VM_PAGER_FAIL 2
82 #define VM_PAGER_PEND 3
83 #define VM_PAGER_ERROR 4
84 #define VM_PAGER_AGAIN 5
86 #define VM_PAGER_PUT_SYNC 0x0001
87 #define VM_PAGER_PUT_INVAL 0x0002
88 #define VM_PAGER_IGNORE_CLEANCHK 0x0004
89 #define VM_PAGER_CLUSTER_OK 0x0008
94 MALLOC_DECLARE(M_VMPGDATA
);
99 extern struct vm_map pager_map
;
100 extern int pager_map_size
;
101 extern struct pagerops
*pagertab
[];
103 vm_object_t
default_pager_alloc(void *, off_t
, vm_prot_t
, off_t
);
104 vm_object_t
dev_pager_alloc(void *, off_t
, vm_prot_t
, off_t
);
105 vm_object_t
phys_pager_alloc(void *, off_t
, vm_prot_t
, off_t
);
106 vm_object_t
swap_pager_alloc(void *, off_t
, vm_prot_t
, off_t
);
107 vm_object_t
vnode_pager_alloc (void *, off_t
, vm_prot_t
, off_t
, int, int);
108 vm_object_t
vnode_pager_reference (struct vnode
*);
110 void vm_pager_bufferinit (void);
111 void vm_pager_deallocate (vm_object_t
);
112 static __inline
int vm_pager_get_page (vm_object_t
, vm_page_t
*, int);
113 static __inline boolean_t
vm_pager_has_page (vm_object_t
, vm_pindex_t
);
114 void vm_pager_sync (void);
115 struct buf
*getchainbuf(struct buf
*bp
, struct vnode
*vp
, int flags
);
116 void flushchainbuf(struct buf
*nbp
);
117 void waitchainbuf(struct buf
*bp
, int count
, int done
);
118 void autochaindone(struct buf
*bp
);
119 void swap_pager_strategy(vm_object_t object
, struct bio
*bio
);
120 void swap_pager_unswapped (vm_page_t m
);
125 * Retrieve the contents of the page from the object pager. Note that the
126 * object pager might replace the page.
128 * If the pagein was successful, we must fully validate it so it can be
133 vm_pager_get_page(vm_object_t object
, vm_page_t
*m
, int seqaccess
)
137 r
= (*pagertab
[object
->type
]->pgo_getpage
)(object
, m
, seqaccess
);
138 if (r
== VM_PAGER_OK
&& (*m
)->valid
!= VM_PAGE_BITS_ALL
) {
139 vm_page_zero_invalid(*m
, TRUE
);
152 (*pagertab
[object
->type
]->pgo_putpages
)
153 (object
, m
, count
, flags
, rtvals
);
159 * Check to see if an object's pager has the requested page. The
160 * object's pager will also set before and after to give the caller
161 * some idea of the number of pages before and after the requested
162 * page can be I/O'd efficiently.
164 * This routine does not have to be called at any particular spl.
167 static __inline boolean_t
168 vm_pager_has_page(vm_object_t object
, vm_pindex_t offset
)
170 return ((*pagertab
[object
->type
]->pgo_haspage
)(object
, offset
));
175 #endif /* _VM_VM_PAGER_H_ */