xref: /freebsd/sys/vm/vm_object.h (revision 11afcc8f9f96d657b8e6f7547c02c1957331fc96)
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 1.49 1998/05/04 17:12:53 dyson Exp $
65  */
66 
67 /*
68  *	Virtual memory object module definitions.
69  */
70 
71 #ifndef	_VM_OBJECT_
72 #define	_VM_OBJECT_
73 
74 #include <sys/queue.h>
75 
76 enum obj_type { OBJT_DEFAULT, OBJT_SWAP, OBJT_VNODE, OBJT_DEVICE, OBJT_DEAD };
77 typedef enum obj_type objtype_t;
78 
79 /*
80  *	Types defined:
81  *
82  *	vm_object_t		Virtual memory object.
83  */
84 
85 struct vm_object {
86 	TAILQ_ENTRY(vm_object) object_list; /* list of all objects */
87 	TAILQ_HEAD(, vm_object) shadow_head; /* objects that this is a shadow for */
88 	TAILQ_ENTRY(vm_object) shadow_list; /* chain of shadow objects */
89 	TAILQ_HEAD(, vm_page) memq;	/* list of resident pages */
90 	int generation;			/* generation ID */
91 	objtype_t type;			/* type of pager */
92 	vm_size_t size;			/* Object size */
93 	int ref_count;			/* How many refs?? */
94 	int shadow_count;		/* how many objects that this is a shadow for */
95 	int pg_color;			/* color of first page in obj */
96 	int	id;					/* ID for no purpose, other than info */
97 	u_short flags;			/* see below */
98 	u_short paging_in_progress;	/* Paging (in or out) so don't collapse or destroy */
99 	u_short	behavior;		/* see below */
100 	int resident_page_count;	/* number of resident pages */
101 	int cache_count;			/* number of cached pages */
102 	int	wire_count;			/* number of wired pages */
103 	vm_ooffset_t paging_offset;	/* Offset into paging space */
104 	struct vm_object *backing_object; /* object that I'm a shadow of */
105 	vm_ooffset_t backing_object_offset;/* Offset in backing object */
106 	vm_offset_t last_read;		/* last read in object -- detect seq behavior */
107 	vm_page_t page_hint;		/* hint for last looked-up or allocated page */
108 	TAILQ_ENTRY(vm_object) pager_object_list; /* list of all objects of this pager type */
109 	void *handle;
110 	union {
111 		struct {
112 			off_t vnp_size; /* Current size of file */
113 		} vnp;
114 		struct {
115 			TAILQ_HEAD(, vm_page) devp_pglist; /* list of pages allocated */
116 		} devp;
117 		struct {
118 			int swp_nblocks;
119 			int swp_allocsize;
120 			struct swblock *swp_blocks;
121 			short swp_poip;
122 		} swp;
123 	} un_pager;
124 };
125 
126 /*
127  * Flags
128  */
129 #define OBJ_ACTIVE	0x0004		/* active objects */
130 #define OBJ_DEAD	0x0008		/* dead objects (during rundown) */
131 #define	OBJ_NOSPLIT	0x0010		/* dont split this object */
132 #define OBJ_PIPWNT	0x0040		/* paging in progress wanted */
133 #define	OBJ_WRITEABLE	0x0080		/* object has been made writable */
134 #define OBJ_MIGHTBEDIRTY	0x0100	/* object might be dirty */
135 #define OBJ_CLEANING	0x0200
136 #define OBJ_OPT		0x1000		/* I/O optimization */
137 #define	OBJ_ONEMAPPING	0x2000		/* One USE (a single, non-forked) mapping flag */
138 
139 #define OBJ_NORMAL	0x0		/* default behavior */
140 #define OBJ_SEQUENTIAL	0x1		/* expect sequential accesses */
141 #define OBJ_RANDOM	0x2		/* expect random accesses */
142 
143 #define IDX_TO_OFF(idx) (((vm_ooffset_t)(idx)) << PAGE_SHIFT)
144 #define OFF_TO_IDX(off) ((vm_pindex_t)(((vm_ooffset_t)(off)) >> PAGE_SHIFT))
145 
146 #ifdef	KERNEL
147 
148 #define	OBJPC_SYNC	0x1			/* sync I/O */
149 #define	OBJPC_INVAL	0x2			/* invalidate */
150 
151 TAILQ_HEAD(object_q, vm_object);
152 
153 extern struct object_q vm_object_list;	/* list of allocated objects */
154 
155  /* lock for object list and count */
156 
157 extern vm_object_t kernel_object;	/* the single kernel object */
158 extern vm_object_t kmem_object;
159 
160 #endif				/* KERNEL */
161 
162 #ifdef KERNEL
163 
164 static __inline void
165 vm_object_pip_add(vm_object_t object, int i)
166 {
167 	int s = splvm();
168 	object->paging_in_progress += i;
169 	splx(s);
170 }
171 
172 static __inline void
173 vm_object_pip_wakeup(vm_object_t object)
174 {
175 	int s = splvm();
176 	object->paging_in_progress--;
177 	splx(s);
178 	if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
179 		object->flags &= ~OBJ_PIPWNT;
180 		wakeup(object);
181 	}
182 }
183 
184 static __inline void
185 vm_object_pip_sleep(vm_object_t object, char *waitid)
186 {
187 	int s;
188 
189 	if (object->paging_in_progress) {
190 		s = splvm();
191 		if (object->paging_in_progress) {
192 			object->flags |= OBJ_PIPWNT;
193 			tsleep(object, PVM, waitid, 0);
194 		}
195 		splx(s);
196 	}
197 }
198 
199 static __inline void
200 vm_object_pip_wait(vm_object_t object, char *waitid)
201 {
202 	while (object->paging_in_progress)
203 		vm_object_pip_sleep(object, waitid);
204 }
205 
206 vm_object_t vm_object_allocate __P((objtype_t, vm_size_t));
207 void _vm_object_allocate __P((objtype_t, vm_size_t, vm_object_t));
208 boolean_t vm_object_coalesce __P((vm_object_t, vm_pindex_t, vm_size_t, vm_size_t));
209 void vm_object_collapse __P((vm_object_t));
210 void vm_object_copy __P((vm_object_t, vm_pindex_t, vm_object_t *, vm_pindex_t *, boolean_t *));
211 void vm_object_deallocate __P((vm_object_t));
212 void vm_object_terminate __P((vm_object_t));
213 void vm_object_vndeallocate __P((vm_object_t));
214 void vm_object_init __P((void));
215 void vm_object_page_clean __P((vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t));
216 void vm_object_page_remove __P((vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t));
217 void vm_object_pmap_copy __P((vm_object_t, vm_pindex_t, vm_pindex_t));
218 void vm_object_pmap_copy_1 __P((vm_object_t, vm_pindex_t, vm_pindex_t));
219 void vm_object_pmap_remove __P((vm_object_t, vm_pindex_t, vm_pindex_t));
220 void vm_object_reference __P((vm_object_t));
221 void vm_object_shadow __P((vm_object_t *, vm_ooffset_t *, vm_size_t));
222 void vm_object_madvise __P((vm_object_t, vm_pindex_t, int, int));
223 void vm_object_init2 __P((void));
224 #endif				/* KERNEL */
225 
226 #endif				/* _VM_OBJECT_ */
227