xref: /freebsd/sys/vm/vm_object.h (revision 282a3889ebf826db9839be296ff1dd903f6d6d6e)
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  * 4. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  *	from: @(#)vm_object.h	8.3 (Berkeley) 1/12/94
33  *
34  *
35  * Copyright (c) 1987, 1990 Carnegie-Mellon University.
36  * All rights reserved.
37  *
38  * Authors: Avadis Tevanian, Jr., Michael Wayne Young
39  *
40  * Permission to use, copy, modify and distribute this software and
41  * its documentation is hereby granted, provided that both the copyright
42  * notice and this permission notice appear in all copies of the
43  * software, derivative works or modified versions, and any portions
44  * thereof, and that both notices appear in supporting documentation.
45  *
46  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
47  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
48  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
49  *
50  * Carnegie Mellon requests users of this software to return to
51  *
52  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
53  *  School of Computer Science
54  *  Carnegie Mellon University
55  *  Pittsburgh PA 15213-3890
56  *
57  * any improvements or extensions that they make and grant Carnegie the
58  * rights to redistribute these changes.
59  *
60  * $FreeBSD$
61  */
62 
63 /*
64  *	Virtual memory object module definitions.
65  */
66 
67 #ifndef	_VM_OBJECT_
68 #define	_VM_OBJECT_
69 
70 #include <sys/queue.h>
71 #include <sys/_lock.h>
72 #include <sys/_mutex.h>
73 
74 /*
75  *	Types defined:
76  *
77  *	vm_object_t		Virtual memory object.
78  *
79  * List of locks
80  *	(c)	const until freed
81  *
82  */
83 
84 struct vm_object {
85 	struct mtx mtx;
86 	TAILQ_ENTRY(vm_object) object_list; /* list of all objects */
87 	LIST_HEAD(, vm_object) shadow_head; /* objects that this is a shadow for */
88 	LIST_ENTRY(vm_object) shadow_list; /* chain of shadow objects */
89 	TAILQ_HEAD(, vm_page) memq;	/* list of resident pages */
90 	vm_page_t root;			/* root of the resident page splay tree */
91 	vm_pindex_t size;		/* Object size */
92 	int generation;			/* generation ID */
93 	int ref_count;			/* How many refs?? */
94 	int shadow_count;		/* how many objects that this is a shadow for */
95 	objtype_t type;			/* type of pager */
96 	u_short flags;			/* see below */
97 	u_short pg_color;		/* (c) color of first page in obj */
98 	u_short paging_in_progress;	/* Paging (in or out) so don't collapse or destroy */
99 	int resident_page_count;	/* number of resident pages */
100 	struct vm_object *backing_object; /* object that I'm a shadow of */
101 	vm_ooffset_t backing_object_offset;/* Offset in backing object */
102 	TAILQ_ENTRY(vm_object) pager_object_list; /* list of all objects of this pager type */
103 	void *handle;
104 	union {
105 		/*
106 		 * VNode pager
107 		 *
108 		 *	vnp_size - current size of file
109 		 */
110 		struct {
111 			off_t vnp_size;
112 		} vnp;
113 
114 		/*
115 		 * Device pager
116 		 *
117 		 *	devp_pglist - list of allocated pages
118 		 */
119 		struct {
120 			TAILQ_HEAD(, vm_page) devp_pglist;
121 		} devp;
122 
123 		/*
124 		 * Swap pager
125 		 *
126 		 *	swp_bcount - number of swap 'swblock' metablocks, each
127 		 *		     contains up to 16 swapblk assignments.
128 		 *		     see vm/swap_pager.h
129 		 */
130 		struct {
131 			int swp_bcount;
132 		} swp;
133 	} un_pager;
134 };
135 
136 /*
137  * Flags
138  */
139 #define OBJ_ACTIVE	0x0004		/* active objects */
140 #define OBJ_DEAD	0x0008		/* dead objects (during rundown) */
141 #define	OBJ_NOSPLIT	0x0010		/* dont split this object */
142 #define OBJ_PIPWNT	0x0040		/* paging in progress wanted */
143 #define OBJ_MIGHTBEDIRTY 0x0100		/* object might be dirty */
144 #define OBJ_CLEANING	0x0200
145 #define	OBJ_ONEMAPPING	0x2000		/* One USE (a single, non-forked) mapping flag */
146 #define	OBJ_DISCONNECTWNT 0x4000	/* disconnect from vnode wanted */
147 #define	OBJ_NEEDGIANT	0x8000		/* object requires Giant */
148 
149 #define IDX_TO_OFF(idx) (((vm_ooffset_t)(idx)) << PAGE_SHIFT)
150 #define OFF_TO_IDX(off) ((vm_pindex_t)(((vm_ooffset_t)(off)) >> PAGE_SHIFT))
151 
152 #ifdef	_KERNEL
153 
154 #define OBJPC_SYNC	0x1			/* sync I/O */
155 #define OBJPC_INVAL	0x2			/* invalidate */
156 #define OBJPC_NOSYNC	0x4			/* skip if PG_NOSYNC */
157 
158 TAILQ_HEAD(object_q, vm_object);
159 
160 extern struct object_q vm_object_list;	/* list of allocated objects */
161 extern struct mtx vm_object_list_mtx;	/* lock for object list and count */
162 
163 extern struct vm_object kernel_object_store;
164 extern struct vm_object kmem_object_store;
165 
166 #define	kernel_object	(&kernel_object_store)
167 #define	kmem_object	(&kmem_object_store)
168 
169 #define	VM_OBJECT_LOCK(object)		mtx_lock(&(object)->mtx)
170 #define	VM_OBJECT_LOCK_ASSERT(object, type) \
171 					mtx_assert(&(object)->mtx, (type))
172 #define	VM_OBJECT_LOCK_INIT(object, type) \
173 					mtx_init(&(object)->mtx, "vm object", \
174 					    (type), MTX_DEF | MTX_DUPOK)
175 #define	VM_OBJECT_LOCKED(object)	mtx_owned(&(object)->mtx)
176 #define	VM_OBJECT_MTX(object)		(&(object)->mtx)
177 #define	VM_OBJECT_TRYLOCK(object)	mtx_trylock(&(object)->mtx)
178 #define	VM_OBJECT_UNLOCK(object)	mtx_unlock(&(object)->mtx)
179 
180 /*
181  *	The object must be locked or thread private.
182  */
183 static __inline void
184 vm_object_set_flag(vm_object_t object, u_short bits)
185 {
186 
187 	object->flags |= bits;
188 }
189 
190 void vm_object_clear_flag(vm_object_t object, u_short bits);
191 void vm_object_pip_add(vm_object_t object, short i);
192 void vm_object_pip_subtract(vm_object_t object, short i);
193 void vm_object_pip_wakeup(vm_object_t object);
194 void vm_object_pip_wakeupn(vm_object_t object, short i);
195 void vm_object_pip_wait(vm_object_t object, char *waitid);
196 
197 vm_object_t vm_object_allocate (objtype_t, vm_pindex_t);
198 void _vm_object_allocate (objtype_t, vm_pindex_t, vm_object_t);
199 boolean_t vm_object_coalesce(vm_object_t, vm_ooffset_t, vm_size_t, vm_size_t);
200 void vm_object_collapse (vm_object_t);
201 void vm_object_deallocate (vm_object_t);
202 void vm_object_terminate (vm_object_t);
203 void vm_object_set_writeable_dirty (vm_object_t);
204 void vm_object_init (void);
205 void vm_object_page_clean (vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t);
206 void vm_object_page_remove (vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t);
207 void vm_object_reference (vm_object_t);
208 void vm_object_reference_locked(vm_object_t);
209 void vm_object_shadow (vm_object_t *, vm_ooffset_t *, vm_size_t);
210 void vm_object_split(vm_map_entry_t);
211 void vm_object_sync(vm_object_t, vm_ooffset_t, vm_size_t, boolean_t,
212     boolean_t);
213 void vm_object_madvise (vm_object_t, vm_pindex_t, int, int);
214 #endif				/* _KERNEL */
215 
216 #endif				/* _VM_OBJECT_ */
217