xref: /freebsd/sys/vm/vm_object.h (revision 8e6b01171e30297084bb0b4457c4183c2746aacc)
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 1.21 1995/07/29 11:44:28 bde Exp $
65  */
66 
67 /*
68  *	Virtual memory object module definitions.
69  */
70 
71 #ifndef	_VM_OBJECT_
72 #define	_VM_OBJECT_
73 
74 #ifdef KERNEL
75 #include <sys/proc.h>		/* XXX for wakeup() */
76 #endif
77 
78 enum obj_type { OBJT_DEFAULT, OBJT_SWAP, OBJT_VNODE, OBJT_DEVICE };
79 typedef enum obj_type objtype_t;
80 
81 /*
82  *	Types defined:
83  *
84  *	vm_object_t		Virtual memory object.
85  */
86 
87 struct vm_object {
88 	TAILQ_ENTRY(vm_object) object_list; /* list of all objects */
89 	TAILQ_ENTRY(vm_object) cached_list; /* list of cached (persistent) objects */
90 	TAILQ_HEAD(, vm_object) shadow_head; /* objects that this is a shadow for */
91 	TAILQ_ENTRY(vm_object) shadow_list; /* chain of shadow objects */
92 	TAILQ_HEAD(, vm_page) memq;	/* list of resident pages */
93 	objtype_t type;			/* type of pager */
94 	vm_size_t size;			/* Object size */
95 	int ref_count;			/* How many refs?? */
96 	u_short flags;			/* see below */
97 	u_short paging_in_progress;	/* Paging (in or out) so don't collapse or destroy */
98 	int resident_page_count;	/* number of resident pages */
99 	vm_offset_t paging_offset;	/* Offset into paging space */
100 	struct vm_object *backing_object; /* object that I'm a shadow of */
101 	vm_offset_t backing_object_offset;/* Offset in backing object */
102 	vm_offset_t last_read;		/* last read in object -- detect seq behavior */
103 	TAILQ_ENTRY(vm_object) pager_object_list; /* list of all objects of this pager type */
104 	void *handle;
105 	union {
106 		struct {
107 			vm_size_t vnp_size; /* Current size of file */
108 		} vnp;
109 		struct {
110 			TAILQ_HEAD(, vm_page) devp_pglist; /* list of pages allocated */
111 		} devp;
112 		struct {
113 			int swp_nblocks;
114 			int swp_allocsize;
115 			struct swblock *swp_blocks;
116 			short swp_poip;
117 		} swp;
118 	} un_pager;
119 };
120 
121 /*
122  * Flags
123  */
124 #define OBJ_CANPERSIST	0x0001		/* allow to persist */
125 #define OBJ_ACTIVE	0x0004		/* active objects */
126 #define OBJ_DEAD	0x0008		/* dead objects (during rundown) */
127 #define	OBJ_PIPWNT	0x0040		/* paging in progress wanted */
128 #define	OBJ_WRITEABLE	0x0080		/* object has been made writable */
129 
130 
131 #ifdef	KERNEL
132 extern int vm_object_cache_max;
133 
134 TAILQ_HEAD(object_q, vm_object);
135 
136 extern struct object_q vm_object_cached_list; /* list of objects persisting */
137 extern int vm_object_cached;		/* size of cached list */
138 
139 extern struct object_q vm_object_list;	/* list of allocated objects */
140 extern long vm_object_count;		/* count of all objects */
141 
142  /* lock for object list and count */
143 
144 extern vm_object_t kernel_object;	/* the single kernel object */
145 extern vm_object_t kmem_object;
146 
147 #endif				/* KERNEL */
148 
149 #ifdef KERNEL
150 static __inline void
151 vm_object_pip_wakeup(vm_object_t object)
152 {
153 	object->paging_in_progress--;
154 	if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
155 		object->flags &= ~OBJ_PIPWNT;
156 		wakeup(object);
157 	}
158 }
159 
160 vm_object_t vm_object_allocate __P((objtype_t, vm_size_t));
161 void vm_object_cache_clear __P((void));
162 void vm_object_cache_trim __P((void));
163 boolean_t vm_object_coalesce __P((vm_object_t, vm_object_t, vm_offset_t, vm_offset_t, vm_offset_t, vm_size_t));
164 void vm_object_collapse __P((vm_object_t));
165 void vm_object_copy __P((vm_object_t, vm_offset_t, vm_size_t, vm_object_t *, vm_offset_t *, boolean_t *));
166 void vm_object_deactivate_pages __P((vm_object_t));
167 void vm_object_deallocate __P((vm_object_t));
168 void vm_object_init __P((vm_size_t));
169 void vm_object_page_clean __P((vm_object_t, vm_offset_t, vm_offset_t, boolean_t, boolean_t));
170 void vm_object_page_remove __P((vm_object_t, vm_offset_t, vm_offset_t, boolean_t));
171 void vm_object_pmap_copy __P((vm_object_t, vm_offset_t, vm_offset_t));
172 void vm_object_pmap_remove __P((vm_object_t, vm_offset_t, vm_offset_t));
173 #ifdef DDB
174 void vm_object_print __P((/* db_expr_t */ int, boolean_t, /* db_expr_t */ int,
175 			  char *));
176 #endif
177 void vm_object_reference __P((vm_object_t));
178 void vm_object_shadow __P((vm_object_t *, vm_offset_t *, vm_size_t));
179 void vm_object_terminate __P((vm_object_t));
180 #endif				/* KERNEL */
181 
182 #endif				/* _VM_OBJECT_ */
183