xref: /freebsd/sys/vm/vm_object.h (revision a316b26e50bbed7cf655fbba726ab87d8ab7599d)
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  *	from: @(#)vm_object.h	8.3 (Berkeley) 1/12/94
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  * $Id: vm_object.h,v 1.3 1994/11/06 05:07:52 davidg Exp $
65  */
66 
67 /*
68  *	Virtual memory object module definitions.
69  */
70 
71 #ifndef	_VM_OBJECT_
72 #define	_VM_OBJECT_
73 
74 #include <vm/vm_page.h>
75 #include <vm/vm_pager.h>
76 
77 /*
78  *	Types defined:
79  *
80  *	vm_object_t		Virtual memory object.
81  */
82 
83 struct vm_object {
84 	struct pglist memq;		/* Resident memory */
85 	 TAILQ_ENTRY(vm_object) object_list; /* list of all objects */
86 	u_short flags;			/* see below */
87 	u_short paging_in_progress;	/* Paging (in or out) so don't collapse or destroy */
88 	int ref_count;			/* How many refs?? */
89 	struct {
90 		int recursion;		/* object locking */
91 		struct proc *proc;	/* process owned */
92 	} lock;
93 	vm_size_t size;			/* Object size */
94 	int resident_page_count;
95 	/* number of resident pages */
96 	struct vm_object *copy;		/* Object that holds copies of my changed pages */
97 	vm_pager_t pager;		/* Where to get data */
98 	vm_offset_t paging_offset;	/* Offset into paging space */
99 	struct vm_object *shadow;	/* My shadow */
100 	vm_offset_t shadow_offset;	/* Offset in shadow */
101 	TAILQ_ENTRY(vm_object) cached_list; /* for persistence */
102 	TAILQ_ENTRY(vm_object) reverse_shadow_list; /* chain of objects that are shadowed */
103 	TAILQ_HEAD(rslist, vm_object) reverse_shadow_head; /* objects that this is a shadow for */
104 };
105 
106 /*
107  * Flags
108  */
109 #define OBJ_CANPERSIST	0x0001		/* allow to persist */
110 #define OBJ_INTERNAL	0x0002		/* internally created object */
111 #define OBJ_ACTIVE	0x0004		/* used to mark active objects */
112 #define OBJ_DEAD	0x0008		/* used to mark dead objects during rundown */
113 #define OBJ_ILOCKED	0x0010		/* lock from modification */
114 #define OBJ_ILOCKWT	0x0020		/* wait for lock from modification */
115 
116 TAILQ_HEAD(vm_object_hash_head, vm_object_hash_entry);
117 
118 struct vm_object_hash_entry {
119 	TAILQ_ENTRY(vm_object_hash_entry) hash_links;	/* hash chain links */
120 	vm_object_t object;		/* object represened */
121 };
122 
123 typedef struct vm_object_hash_entry *vm_object_hash_entry_t;
124 
125 #ifdef	KERNEL
126 TAILQ_HEAD(object_q, vm_object);
127 
128 struct object_q vm_object_cached_list;	/* list of objects persisting */
129 int vm_object_cached;			/* size of cached list */
130 simple_lock_data_t vm_cache_lock;	/* lock for object cache */
131 
132 struct object_q vm_object_list;		/* list of allocated objects */
133 long vm_object_count;			/* count of all objects */
134 simple_lock_data_t vm_object_list_lock;
135 
136  /* lock for object list and count */
137 
138 vm_object_t kernel_object;		/* the single kernel object */
139 vm_object_t kmem_object;
140 
141 #define	vm_object_cache_lock()		simple_lock(&vm_cache_lock)
142 #define	vm_object_cache_unlock()	simple_unlock(&vm_cache_lock)
143 #endif				/* KERNEL */
144 
145 #define	vm_object_sleep(event, object, interruptible) \
146 					thread_sleep((event), &(object)->Lock, (interruptible))
147 #if 0
148 #define	vm_object_lock_init(object)	simple_lock_init(&(object)->Lock)
149 #define	vm_object_lock(object)		simple_lock(&(object)->Lock)
150 #define	vm_object_unlock(object)	simple_unlock(&(object)->Lock)
151 #define	vm_object_lock_try(object)	simple_lock_try(&(object)->Lock)
152 #endif
153 #define	vm_object_lock_init(object) (object->flags &= ~OBJ_ILOCKED, object->lock.recursion = 0, object->lock.proc = 0)
154 
155 static __inline void
156 vm_object_lock(vm_object_t obj)
157 {
158 	if (obj->flags & OBJ_ILOCKED) {
159 		++obj->lock.recursion;
160 		return;
161 	}
162 	obj->flags |= OBJ_ILOCKED;
163 	obj->lock.recursion = 1;
164 }
165 
166 static __inline void
167 vm_object_unlock(vm_object_t obj)
168 {
169 	--obj->lock.recursion;
170 	if (obj->lock.recursion != 0)
171 		return;
172 	obj->flags &= ~OBJ_ILOCKED;
173 }
174 
175 static __inline int
176 vm_object_lock_try(vm_object_t obj)
177 {
178 	if (obj->flags & OBJ_ILOCKED) {
179 		++obj->lock.recursion;
180 		return 1;
181 	}
182 	obj->flags |= OBJ_ILOCKED;
183 	obj->lock.recursion = 1;
184 	return 1;
185 }
186 
187 #ifdef KERNEL
188 vm_object_t vm_object_allocate __P((vm_size_t));
189 void vm_object_cache_clear __P((void));
190 void vm_object_cache_trim __P((void));
191 boolean_t vm_object_coalesce __P((vm_object_t, vm_object_t, vm_offset_t, vm_offset_t, vm_offset_t, vm_size_t));
192 void vm_object_collapse __P((vm_object_t));
193 void vm_object_copy __P((vm_object_t, vm_offset_t, vm_size_t, vm_object_t *, vm_offset_t *, boolean_t *));
194 void vm_object_deactivate_pages __P((vm_object_t));
195 void vm_object_deallocate __P((vm_object_t));
196 void vm_object_enter __P((vm_object_t, vm_pager_t));
197 void vm_object_init __P((vm_size_t));
198 vm_object_t vm_object_lookup __P((vm_pager_t));
199 boolean_t vm_object_page_clean __P((vm_object_t, vm_offset_t, vm_offset_t, boolean_t, boolean_t));
200 void vm_object_page_remove __P((vm_object_t, vm_offset_t, vm_offset_t));
201 void vm_object_pmap_copy __P((vm_object_t, vm_offset_t, vm_offset_t));
202 void vm_object_pmap_remove __P((vm_object_t, vm_offset_t, vm_offset_t));
203 void vm_object_print __P((vm_object_t, boolean_t));
204 void vm_object_reference __P((vm_object_t));
205 void vm_object_remove __P((vm_pager_t));
206 void vm_object_setpager __P((vm_object_t, vm_pager_t, vm_offset_t, boolean_t));
207 void vm_object_shadow __P((vm_object_t *, vm_offset_t *, vm_size_t));
208 void vm_object_terminate __P((vm_object_t));
209 
210 #endif
211 #endif				/* _VM_OBJECT_ */
212