vm_object.h revision 12110 
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 1.22 1995/08/26 23:19:49 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
78enum obj_type { OBJT_DEFAULT, OBJT_SWAP, OBJT_VNODE, OBJT_DEVICE };
79typedef enum obj_type objtype_t;
80
81/*
82 *	Types defined:
83 *
84 *	vm_object_t		Virtual memory object.
85 */
86
87struct 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#define	OBJ_MIGHTBEDIRTY	0x0100	/* object might be dirty */
130#define OBJ_CLEANING	0x0200
131
132
133#ifdef	KERNEL
134extern int vm_object_cache_max;
135
136TAILQ_HEAD(object_q, vm_object);
137
138extern struct object_q vm_object_cached_list; /* list of objects persisting */
139extern int vm_object_cached;		/* size of cached list */
140
141extern struct object_q vm_object_list;	/* list of allocated objects */
142extern long vm_object_count;		/* count of all objects */
143
144 /* lock for object list and count */
145
146extern vm_object_t kernel_object;	/* the single kernel object */
147extern vm_object_t kmem_object;
148
149#endif				/* KERNEL */
150
151#ifdef KERNEL
152static __inline void
153vm_object_pip_wakeup(vm_object_t object)
154{
155	object->paging_in_progress--;
156	if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
157		object->flags &= ~OBJ_PIPWNT;
158		wakeup(object);
159	}
160}
161
162vm_object_t vm_object_allocate __P((objtype_t, vm_size_t));
163void vm_object_cache_clear __P((void));
164void vm_object_cache_trim __P((void));
165boolean_t vm_object_coalesce __P((vm_object_t, vm_object_t, vm_offset_t, vm_offset_t, vm_offset_t, vm_size_t));
166void vm_object_collapse __P((vm_object_t));
167void vm_object_copy __P((vm_object_t, vm_offset_t, vm_size_t, vm_object_t *, vm_offset_t *, boolean_t *));
168void vm_object_deactivate_pages __P((vm_object_t));
169void vm_object_deallocate __P((vm_object_t));
170void vm_object_init __P((vm_size_t));
171void vm_object_page_clean __P((vm_object_t, vm_offset_t, vm_offset_t, boolean_t, boolean_t));
172void vm_object_page_remove __P((vm_object_t, vm_offset_t, vm_offset_t, boolean_t));
173void vm_object_pmap_copy __P((vm_object_t, vm_offset_t, vm_offset_t));
174void vm_object_pmap_remove __P((vm_object_t, vm_offset_t, vm_offset_t));
175#ifdef DDB
176void vm_object_print __P((/* db_expr_t */ int, boolean_t, /* db_expr_t */ int,
177			  char *));
178#endif
179void vm_object_reference __P((vm_object_t));
180void vm_object_shadow __P((vm_object_t *, vm_offset_t *, vm_size_t));
181void vm_object_terminate __P((vm_object_t));
182#endif				/* KERNEL */
183
184#endif				/* _VM_OBJECT_ */
185