vm_object.h revision 6129 
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 1.5 1995/01/24 10:13:24 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
83struct vm_object {
84	struct pglist memq;		/* Resident memory */
85	TAILQ_HEAD(rslist, vm_object) reverse_shadow_head; /* objects that this is a shadow for */
86	TAILQ_ENTRY(vm_object) object_list; /* list of all objects */
87	TAILQ_ENTRY(vm_object) reverse_shadow_list; /* chain of objects that are shadowed */
88	TAILQ_ENTRY(vm_object) cached_list; /* for persistence */
89	vm_size_t size;			/* Object size */
90	int ref_count;			/* How many refs?? */
91	struct {
92		int recursion;		/* object locking */
93		struct proc *proc;	/* process owned */
94	} lock;
95	u_short flags;			/* see below */
96	u_short paging_in_progress;	/* Paging (in or out) so don't collapse or destroy */
97	int resident_page_count;	/* number of resident pages */
98	vm_pager_t pager;		/* Where to get data */
99	vm_offset_t paging_offset;	/* Offset into paging space */
100	struct vm_object *shadow;	/* My shadow */
101	vm_offset_t shadow_offset;	/* Offset in shadow */
102	struct vm_object *copy;		/* Object that holds copies of my changed pages */
103	vm_offset_t last_read;		/* last read in object -- detect seq behavior */
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
116TAILQ_HEAD(vm_object_hash_head, vm_object_hash_entry);
117
118struct 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
123typedef struct vm_object_hash_entry *vm_object_hash_entry_t;
124
125#ifdef	KERNEL
126TAILQ_HEAD(object_q, vm_object);
127
128struct object_q vm_object_cached_list;	/* list of objects persisting */
129int vm_object_cached;			/* size of cached list */
130simple_lock_data_t vm_cache_lock;	/* lock for object cache */
131
132struct object_q vm_object_list;		/* list of allocated objects */
133long vm_object_count;			/* count of all objects */
134simple_lock_data_t vm_object_list_lock;
135
136 /* lock for object list and count */
137
138vm_object_t kernel_object;		/* the single kernel object */
139vm_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
155static __inline void
156vm_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
166static __inline void
167vm_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
175static __inline int
176vm_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
188vm_object_t vm_object_allocate __P((vm_size_t));
189void vm_object_cache_clear __P((void));
190void vm_object_cache_trim __P((void));
191boolean_t vm_object_coalesce __P((vm_object_t, vm_object_t, vm_offset_t, vm_offset_t, vm_offset_t, vm_size_t));
192void vm_object_collapse __P((vm_object_t));
193void vm_object_copy __P((vm_object_t, vm_offset_t, vm_size_t, vm_object_t *, vm_offset_t *, boolean_t *));
194void vm_object_deactivate_pages __P((vm_object_t));
195void vm_object_deallocate __P((vm_object_t));
196void vm_object_enter __P((vm_object_t, vm_pager_t));
197void vm_object_init __P((vm_size_t));
198vm_object_t vm_object_lookup __P((vm_pager_t));
199boolean_t vm_object_page_clean __P((vm_object_t, vm_offset_t, vm_offset_t, boolean_t, boolean_t));
200void vm_object_page_remove __P((vm_object_t, vm_offset_t, vm_offset_t));
201void vm_object_pmap_copy __P((vm_object_t, vm_offset_t, vm_offset_t));
202void vm_object_pmap_remove __P((vm_object_t, vm_offset_t, vm_offset_t));
203void vm_object_print __P((vm_object_t, boolean_t));
204void vm_object_reference __P((vm_object_t));
205void vm_object_remove __P((vm_pager_t));
206void vm_object_setpager __P((vm_object_t, vm_pager_t, vm_offset_t, boolean_t));
207void vm_object_shadow __P((vm_object_t *, vm_offset_t *, vm_size_t));
208void vm_object_terminate __P((vm_object_t));
209
210#endif
211#endif				/* _VM_OBJECT_ */
212