xref: /freebsd/sys/vm/vm_map.h (revision 26f9a767)
1 /*
2  * Copyright (c) 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * The Mach Operating System project at Carnegie-Mellon University.
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  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)vm_map.h	8.3 (Berkeley) 3/15/94
37  *
38  *
39  * Copyright (c) 1987, 1990 Carnegie-Mellon University.
40  * All rights reserved.
41  *
42  * Authors: Avadis Tevanian, Jr., Michael Wayne Young
43  *
44  * Permission to use, copy, modify and distribute this software and
45  * its documentation is hereby granted, provided that both the copyright
46  * notice and this permission notice appear in all copies of the
47  * software, derivative works or modified versions, and any portions
48  * thereof, and that both notices appear in supporting documentation.
49  *
50  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
51  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
52  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
53  *
54  * Carnegie Mellon requests users of this software to return to
55  *
56  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
57  *  School of Computer Science
58  *  Carnegie Mellon University
59  *  Pittsburgh PA 15213-3890
60  *
61  * any improvements or extensions that they make and grant Carnegie the
62  * rights to redistribute these changes.
63  */
64 
65 /*
66  *	Virtual memory map module definitions.
67  */
68 
69 #ifndef	_VM_MAP_
70 #define	_VM_MAP_
71 
72 /*
73  *	Types defined:
74  *
75  *	vm_map_t		the high-level address map data structure.
76  *	vm_map_entry_t		an entry in an address map.
77  *	vm_map_version_t	a timestamp of a map, for use with vm_map_lookup
78  */
79 
80 /*
81  *	Objects which live in maps may be either VM objects, or
82  *	another map (called a "sharing map") which denotes read-write
83  *	sharing with other maps.
84  */
85 
86 union vm_map_object {
87 	struct vm_object	*vm_object;	/* object object */
88 	struct vm_map		*share_map;	/* share map */
89 	struct vm_map		*sub_map;	/* belongs to another map */
90 };
91 
92 /*
93  *	Address map entries consist of start and end addresses,
94  *	a VM object (or sharing map) and offset into that object,
95  *	and user-exported inheritance and protection information.
96  *	Also included is control information for virtual copy operations.
97  */
98 struct vm_map_entry {
99 	struct vm_map_entry	*prev;		/* previous entry */
100 	struct vm_map_entry	*next;		/* next entry */
101 	vm_offset_t		start;		/* start address */
102 	vm_offset_t		end;		/* end address */
103 	union vm_map_object	object;		/* object I point to */
104 	vm_offset_t		offset;		/* offset into object */
105 	boolean_t		is_a_map:1,	/* Is "object" a map? */
106 				is_sub_map:1,	/* Is "object" a submap? */
107 		/* Only in sharing maps: */
108 				copy_on_write:1,/* is data copy-on-write */
109 				needs_copy:1;	/* does object need to be copied */
110 		/* Only in task maps: */
111 	vm_prot_t		protection;	/* protection code */
112 	vm_prot_t		max_protection;	/* maximum protection */
113 	vm_inherit_t		inheritance;	/* inheritance */
114 	int			wired_count;	/* can be paged if = 0 */
115 };
116 
117 /*
118  *	Maps are doubly-linked lists of map entries, kept sorted
119  *	by address.  A single hint is provided to start
120  *	searches again from the last successful search,
121  *	insertion, or removal.
122  */
123 struct vm_map {
124 	struct pmap *		pmap;		/* Physical map */
125 	lock_data_t		lock;		/* Lock for map data */
126 	struct vm_map_entry	header;		/* List of entries */
127 	int			nentries;	/* Number of entries */
128 	vm_size_t		size;		/* virtual size */
129 	boolean_t		is_main_map;	/* Am I a main map? */
130 	int			ref_count;	/* Reference count */
131 	simple_lock_data_t	ref_lock;	/* Lock for ref_count field */
132 	vm_map_entry_t		hint;		/* hint for quick lookups */
133 	simple_lock_data_t	hint_lock;	/* lock for hint storage */
134 	vm_map_entry_t		first_free;	/* First free space hint */
135 	boolean_t		entries_pageable; /* map entries pageable?? */
136 	unsigned int		timestamp;	/* Version number */
137 #define	min_offset		header.start
138 #define max_offset		header.end
139 };
140 
141 /*
142  *	Map versions are used to validate a previous lookup attempt.
143  *
144  *	Since lookup operations may involve both a main map and
145  *	a sharing map, it is necessary to have a timestamp from each.
146  *	[If the main map timestamp has changed, the share_map and
147  *	associated timestamp are no longer valid; the map version
148  *	does not include a reference for the imbedded share_map.]
149  */
150 typedef struct {
151 	int		main_timestamp;
152 	vm_map_t	share_map;
153 	int		share_timestamp;
154 } vm_map_version_t;
155 
156 /*
157  *	Macros:		vm_map_lock, etc.
158  *	Function:
159  *		Perform locking on the data portion of a map.
160  */
161 
162 #define	vm_map_lock(map) { \
163 	lock_write(&(map)->lock); \
164 	(map)->timestamp++; \
165 }
166 #define	vm_map_unlock(map)	lock_write_done(&(map)->lock)
167 #define	vm_map_lock_read(map)	lock_read(&(map)->lock)
168 #define	vm_map_unlock_read(map)	lock_read_done(&(map)->lock)
169 
170 /*
171  *	Functions implemented as macros
172  */
173 #define		vm_map_min(map)		((map)->min_offset)
174 #define		vm_map_max(map)		((map)->max_offset)
175 #define		vm_map_pmap(map)	((map)->pmap)
176 
177 /* XXX: number of kernel maps and entries to statically allocate */
178 #define MAX_KMAP	10
179 #define	MAX_KMAPENT	128
180 
181 #ifdef KERNEL
182 boolean_t	 vm_map_check_protection __P((vm_map_t,
183 		    vm_offset_t, vm_offset_t, vm_prot_t));
184 int		 vm_map_copy __P((vm_map_t, vm_map_t, vm_offset_t,
185 		    vm_size_t, vm_offset_t, boolean_t, boolean_t));
186 void		 vm_map_copy_entry __P((vm_map_t,
187 		    vm_map_t, vm_map_entry_t, vm_map_entry_t));
188 struct pmap;
189 vm_map_t	 vm_map_create __P((struct pmap *,
190 		    vm_offset_t, vm_offset_t, boolean_t));
191 void		 vm_map_deallocate __P((vm_map_t));
192 int		 vm_map_delete __P((vm_map_t, vm_offset_t, vm_offset_t));
193 vm_map_entry_t	 vm_map_entry_create __P((vm_map_t));
194 void		 vm_map_entry_delete __P((vm_map_t, vm_map_entry_t));
195 void		 vm_map_entry_dispose __P((vm_map_t, vm_map_entry_t));
196 void		 vm_map_entry_unwire __P((vm_map_t, vm_map_entry_t));
197 int		 vm_map_find __P((vm_map_t, vm_object_t,
198 		    vm_offset_t, vm_offset_t *, vm_size_t, boolean_t));
199 int		 vm_map_findspace __P((vm_map_t,
200 		    vm_offset_t, vm_size_t, vm_offset_t *));
201 int		 vm_map_inherit __P((vm_map_t,
202 		    vm_offset_t, vm_offset_t, vm_inherit_t));
203 void		 vm_map_init __P((struct vm_map *,
204 		    vm_offset_t, vm_offset_t, boolean_t));
205 int		 vm_map_insert __P((vm_map_t,
206 		    vm_object_t, vm_offset_t, vm_offset_t, vm_offset_t));
207 int		 vm_map_lookup __P((vm_map_t *, vm_offset_t, vm_prot_t,
208 		    vm_map_entry_t *, vm_object_t *, vm_offset_t *, vm_prot_t *,
209 		    boolean_t *, boolean_t *));
210 void		 vm_map_lookup_done __P((vm_map_t, vm_map_entry_t));
211 boolean_t	 vm_map_lookup_entry __P((vm_map_t,
212 		    vm_offset_t, vm_map_entry_t *));
213 int		 vm_map_pageable __P((vm_map_t,
214 		    vm_offset_t, vm_offset_t, boolean_t));
215 int		 vm_map_clean __P((vm_map_t,
216 		    vm_offset_t, vm_offset_t, boolean_t, boolean_t));
217 void		 vm_map_print __P((vm_map_t, boolean_t));
218 int		 vm_map_protect __P((vm_map_t,
219 		    vm_offset_t, vm_offset_t, vm_prot_t, boolean_t));
220 void		 vm_map_reference __P((vm_map_t));
221 int		 vm_map_remove __P((vm_map_t, vm_offset_t, vm_offset_t));
222 void		 vm_map_simplify __P((vm_map_t, vm_offset_t));
223 void		 vm_map_simplify_entry __P((vm_map_t, vm_map_entry_t));
224 void		 vm_map_startup __P((void));
225 int		 vm_map_submap __P((vm_map_t,
226 		    vm_offset_t, vm_offset_t, vm_map_t));
227 #endif
228 #endif /* _VM_MAP_ */
229