xref: /freebsd/sys/vm/vm_object.h (revision 74bf4e164ba5851606a27d4feff27717452583e5)
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 enum obj_type { OBJT_DEFAULT, OBJT_SWAP, OBJT_VNODE, OBJT_DEVICE, OBJT_PHYS,
75 		OBJT_DEAD };
76 typedef u_char objtype_t;
77 
78 /*
79  *	Types defined:
80  *
81  *	vm_object_t		Virtual memory object.
82  *
83  * List of locks
84  *	(c)	const until freed
85  *
86  */
87 
88 struct vm_object {
89 	struct mtx mtx;
90 	TAILQ_ENTRY(vm_object) object_list; /* list of all objects */
91 	LIST_HEAD(, vm_object) shadow_head; /* objects that this is a shadow for */
92 	LIST_ENTRY(vm_object) shadow_list; /* chain of shadow objects */
93 	TAILQ_HEAD(, vm_page) memq;	/* list of resident pages */
94 	vm_page_t root;			/* root of the resident page splay tree */
95 	vm_pindex_t size;		/* Object size */
96 	int generation;			/* generation ID */
97 	int ref_count;			/* How many refs?? */
98 	int shadow_count;		/* how many objects that this is a shadow for */
99 	objtype_t type;			/* type of pager */
100 	u_short flags;			/* see below */
101 	u_short pg_color;		/* (c) color of first page in obj */
102 	u_short paging_in_progress;	/* Paging (in or out) so don't collapse or destroy */
103 	int resident_page_count;	/* number of resident pages */
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 	TAILQ_ENTRY(vm_object) pager_object_list; /* list of all objects of this pager type */
107 	void *handle;
108 	union {
109 		/*
110 		 * VNode pager
111 		 *
112 		 *	vnp_size - current size of file
113 		 */
114 		struct {
115 			off_t vnp_size;
116 		} vnp;
117 
118 		/*
119 		 * Device pager
120 		 *
121 		 *	devp_pglist - list of allocated pages
122 		 */
123 		struct {
124 			TAILQ_HEAD(, vm_page) devp_pglist;
125 		} devp;
126 
127 		/*
128 		 * Swap pager
129 		 *
130 		 *	swp_bcount - number of swap 'swblock' metablocks, each
131 		 *		     contains up to 16 swapblk assignments.
132 		 *		     see vm/swap_pager.h
133 		 */
134 		struct {
135 			int swp_bcount;
136 		} swp;
137 	} un_pager;
138 };
139 
140 /*
141  * Flags
142  */
143 #define OBJ_ACTIVE	0x0004		/* active objects */
144 #define OBJ_DEAD	0x0008		/* dead objects (during rundown) */
145 #define	OBJ_NOSPLIT	0x0010		/* dont split this object */
146 #define OBJ_PIPWNT	0x0040		/* paging in progress wanted */
147 #define	OBJ_WRITEABLE	0x0080		/* object has been made writable */
148 #define OBJ_MIGHTBEDIRTY 0x0100		/* object might be dirty */
149 #define OBJ_CLEANING	0x0200
150 #define	OBJ_ONEMAPPING	0x2000		/* One USE (a single, non-forked) mapping flag */
151 
152 #define IDX_TO_OFF(idx) (((vm_ooffset_t)(idx)) << PAGE_SHIFT)
153 #define OFF_TO_IDX(off) ((vm_pindex_t)(((vm_ooffset_t)(off)) >> PAGE_SHIFT))
154 
155 #ifdef	_KERNEL
156 
157 #define OBJPC_SYNC	0x1			/* sync I/O */
158 #define OBJPC_INVAL	0x2			/* invalidate */
159 #define OBJPC_NOSYNC	0x4			/* skip if PG_NOSYNC */
160 
161 TAILQ_HEAD(object_q, vm_object);
162 
163 extern struct object_q vm_object_list;	/* list of allocated objects */
164 extern struct mtx vm_object_list_mtx;	/* lock for object list and count */
165 
166 extern struct vm_object kernel_object_store;
167 extern struct vm_object kmem_object_store;
168 
169 #define	kernel_object	(&kernel_object_store)
170 #define	kmem_object	(&kmem_object_store)
171 
172 #define	VM_OBJECT_LOCK(object)		mtx_lock(&(object)->mtx)
173 #define	VM_OBJECT_LOCK_ASSERT(object, type) \
174 					mtx_assert(&(object)->mtx, (type))
175 #define	VM_OBJECT_LOCK_INIT(object, type) \
176 					mtx_init(&(object)->mtx, "vm object", \
177 					    (type), MTX_DEF | MTX_DUPOK)
178 #define	VM_OBJECT_LOCKED(object)	mtx_owned(&(object)->mtx)
179 #define	VM_OBJECT_MTX(object)		(&(object)->mtx)
180 #define	VM_OBJECT_TRYLOCK(object)	mtx_trylock(&(object)->mtx)
181 #define	VM_OBJECT_UNLOCK(object)	mtx_unlock(&(object)->mtx)
182 
183 /*
184  *	The object must be locked or thread private.
185  */
186 static __inline void
187 vm_object_set_flag(vm_object_t object, u_short bits)
188 {
189 
190 	object->flags |= bits;
191 }
192 
193 void vm_object_clear_flag(vm_object_t object, u_short bits);
194 void vm_object_pip_add(vm_object_t object, short i);
195 void vm_object_pip_subtract(vm_object_t object, short i);
196 void vm_object_pip_wakeup(vm_object_t object);
197 void vm_object_pip_wakeupn(vm_object_t object, short i);
198 void vm_object_pip_wait(vm_object_t object, char *waitid);
199 
200 vm_object_t vm_object_allocate (objtype_t, vm_pindex_t);
201 vm_object_t vm_object_allocate_wait (objtype_t, vm_pindex_t, int);
202 void _vm_object_allocate (objtype_t, vm_pindex_t, vm_object_t);
203 boolean_t vm_object_coalesce(vm_object_t, vm_ooffset_t, vm_size_t, vm_size_t);
204 void vm_object_collapse (vm_object_t);
205 void vm_object_deallocate (vm_object_t);
206 void vm_object_terminate (vm_object_t);
207 void vm_object_vndeallocate (vm_object_t);
208 void vm_object_set_writeable_dirty (vm_object_t);
209 void vm_object_init (void);
210 void vm_object_page_clean (vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t);
211 void vm_object_page_remove (vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t);
212 void vm_object_reference (vm_object_t);
213 void vm_object_reference_locked(vm_object_t);
214 void vm_object_shadow (vm_object_t *, vm_ooffset_t *, vm_size_t);
215 void vm_object_split(vm_map_entry_t);
216 void vm_object_sync(vm_object_t, vm_ooffset_t, vm_size_t, boolean_t,
217     boolean_t);
218 void vm_object_madvise (vm_object_t, vm_pindex_t, int, int);
219 #endif				/* _KERNEL */
220 
221 #endif				/* _VM_OBJECT_ */
222