xref: /openbsd/sys/uvm/uvm_pager.h (revision d6b79e51)
1 /*	$OpenBSD: uvm_pager.h,v 1.33 2021/10/12 07:38:22 mpi Exp $	*/
2 /*	$NetBSD: uvm_pager.h,v 1.20 2000/11/27 08:40:05 chs Exp $	*/
3 
4 /*
5  * Copyright (c) 1997 Charles D. Cranor and Washington University.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  *
28  * from: Id: uvm_pager.h,v 1.1.2.14 1998/01/13 19:00:50 chuck Exp
29  */
30 
31 /*
32  * Copyright (c) 1990 University of Utah.
33  * Copyright (c) 1991, 1993
34  *	The Regents of the University of California.  All rights reserved.
35  *
36  * This code is derived from software contributed to Berkeley by
37  * the Systems Programming Group of the University of Utah Computer
38  * Science Department.
39  *
40  * Redistribution and use in source and binary forms, with or without
41  * modification, are permitted provided that the following conditions
42  * are met:
43  * 1. Redistributions of source code must retain the above copyright
44  *    notice, this list of conditions and the following disclaimer.
45  * 2. Redistributions in binary form must reproduce the above copyright
46  *    notice, this list of conditions and the following disclaimer in the
47  *    documentation and/or other materials provided with the distribution.
48  * 3. Neither the name of the University nor the names of its contributors
49  *    may be used to endorse or promote products derived from this software
50  *    without specific prior written permission.
51  *
52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62  * SUCH DAMAGE.
63  *
64  *	@(#)vm_pager.h	8.5 (Berkeley) 7/7/94
65  */
66 
67 #ifndef _UVM_UVM_PAGER_H_
68 #define _UVM_UVM_PAGER_H_
69 
70 #ifdef _KERNEL
71 
72 struct uvm_pagerops {
73 						/* init pager */
74 	void			(*pgo_init)(void);
75 						/* add reference to obj */
76 	void			(*pgo_reference)(struct uvm_object *);
77 						/* drop reference to obj */
78 	void			(*pgo_detach)(struct uvm_object *);
79 						/* special nonstd fault fn */
80 	int			(*pgo_fault)(struct uvm_faultinfo *, vaddr_t,
81 				 vm_page_t *, int, int, vm_fault_t,
82 				 vm_prot_t, int);
83 						/* flush pages out of obj */
84 	boolean_t		(*pgo_flush)(struct uvm_object *, voff_t,
85 				 voff_t, int);
86 						/* get/read page */
87 	int			(*pgo_get)(struct uvm_object *, voff_t,
88 				 vm_page_t *, int *, int, vm_prot_t, int, int);
89 						/* put/write page */
90 	int			(*pgo_put)(struct uvm_object *, vm_page_t *,
91 				 int, boolean_t);
92 						/* return range of cluster */
93 	void			(*pgo_cluster)(struct uvm_object *, voff_t,
94 				 voff_t *, voff_t *);
95 						/* make "put" cluster */
96 	struct vm_page **	(*pgo_mk_pcluster)(struct uvm_object *,
97 				 struct vm_page **, int *, struct vm_page *,
98 				 int, voff_t, voff_t);
99 };
100 
101 /* pager flags [mostly for flush] */
102 
103 #define PGO_CLEANIT	0x001	/* write dirty pages to backing store */
104 #define PGO_SYNCIO	0x002	/* if PGO_CLEANIT: use sync I/O? */
105 #define PGO_DEACTIVATE	0x004	/* deactivate flushed pages */
106 #define PGO_FREE	0x008	/* free flushed pages */
107 /* if PGO_FREE is not set then the pages stay where they are. */
108 
109 #define PGO_ALLPAGES	0x010	/* flush whole object/get all pages */
110 #define PGO_DOACTCLUST	0x020	/* flag to mk_pcluster to include active */
111 #define PGO_LOCKED	0x040	/* fault data structures are locked [get] */
112 #define PGO_PDFREECLUST	0x080	/* daemon's free cluster flag [uvm_pager_put] */
113 #define PGO_REALLOCSWAP	0x100	/* reallocate swap area [pager_dropcluster] */
114 #define PGO_NOWAIT	0x200	/* do not wait for inode lock */
115 
116 /* page we are not interested in getting */
117 #define PGO_DONTCARE ((struct vm_page *) -1L)	/* [get only] */
118 
119 /*
120  * prototypes
121  */
122 
123 void		uvm_pager_dropcluster(struct uvm_object *, struct vm_page *,
124 		    struct vm_page **, int *, int);
125 void		uvm_pager_init(void);
126 int		uvm_pager_put(struct uvm_object *, struct vm_page *,
127 		    struct vm_page ***, int *, int, voff_t, voff_t);
128 
129 
130 vaddr_t		uvm_pagermapin(struct vm_page **, int, int);
131 void		uvm_pagermapout(vaddr_t, int);
132 struct vm_page **uvm_mk_pcluster(struct uvm_object *, struct vm_page **,
133 		    int *, struct vm_page *, int, voff_t, voff_t);
134 
135 /* Flags to uvm_pagermapin() */
136 #define	UVMPAGER_MAPIN_WAITOK	0x01	/* it's okay to wait */
137 #define	UVMPAGER_MAPIN_READ	0x02	/* host <- device */
138 #define	UVMPAGER_MAPIN_WRITE	0x00	/* device -> host (pseudo flag) */
139 
140 /*
141  * get/put return values
142  * OK	   operation was successful
143  * BAD	   specified data was out of the accepted range
144  * FAIL	   specified data was in range, but doesn't exist
145  * PEND	   operations was initiated but not completed
146  * ERROR   error while accessing data that is in range and exists
147  * AGAIN   temporary resource shortage prevented operation from happening
148  * UNLOCK  unlock the map and try again
149  * REFAULT [uvm_fault internal use only!] unable to relock data structures,
150  *         thus the mapping needs to be reverified before we can proceed
151  */
152 #define	VM_PAGER_OK		0
153 #define	VM_PAGER_BAD		1
154 #define	VM_PAGER_FAIL		2
155 #define	VM_PAGER_PEND		3
156 #define	VM_PAGER_ERROR		4
157 #define VM_PAGER_AGAIN		5
158 #define VM_PAGER_UNLOCK		6
159 #define VM_PAGER_REFAULT	7
160 
161 /*
162  * XXX
163  * this is needed until the device strategy interface
164  * is changed to do physically-addressed i/o.
165  */
166 
167 #ifndef PAGER_MAP_SIZE
168 #define PAGER_MAP_SIZE       (16 * 1024 * 1024)
169 #endif
170 
171 #endif /* _KERNEL */
172 
173 #endif /* _UVM_UVM_PAGER_H_ */
174