xref: /dflybsd-src/sys/vm/vm_object.h (revision 96adc7538c33c47d4e6fce31d06ccf00f5aac3fa)
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  * $FreeBSD: src/sys/vm/vm_object.h,v 1.63.2.3 2003/05/26 19:17:56 alc Exp $
65  * $DragonFly: src/sys/vm/vm_object.h,v 1.14 2007/06/08 02:00:47 dillon Exp $
66  */
67 
68 /*
69  *	Virtual memory object module definitions.
70  */
71 
72 #ifndef	_VM_VM_OBJECT_H_
73 #define	_VM_VM_OBJECT_H_
74 
75 #ifndef _SYS_TYPES_H_
76 #include <sys/types.h>
77 #endif
78 #if defined(_KERNEL) && !defined(_SYS_SYSTM_H_)
79 #include <sys/systm.h>
80 #endif
81 #ifndef _SYS_QUEUE_H_
82 #include <sys/queue.h>
83 #endif
84 #ifndef _SYS_TREE_H_
85 #include <sys/tree.h>
86 #endif
87 #ifndef _MACHINE_ATOMIC_H_
88 #include <machine/atomic.h>
89 #endif
90 #ifndef _VM_VM_H_
91 #include <vm/vm.h>
92 #endif
93 #ifndef _VM_VM_PAGE_H_
94 #include <vm/vm_page.h>
95 #endif
96 
97 #ifdef _KERNEL
98 
99 #ifndef _SYS_THREAD2_H_
100 #include <sys/thread2.h>
101 #endif
102 
103 #endif
104 
105 struct swblock;
106 struct swblock_rb_tree;
107 int rb_swblock_compare(struct swblock *, struct swblock *);
108 
109 RB_PROTOTYPE2(swblock_rb_tree, swblock, swb_entry, rb_swblock_compare,
110 	      vm_pindex_t);
111 
112 enum obj_type {
113 	OBJT_DEFAULT,
114 	OBJT_SWAP,   	/* object backed by swap blocks */
115 	OBJT_VNODE, 	/* object backed by file pages (vnode) */
116 	OBJT_DEVICE, 	/* object backed by device pages */
117 	OBJT_PHYS,  	/* object backed by physical pages */
118 	OBJT_DEAD   	/* dead object */
119 };
120 typedef u_char objtype_t;
121 
122 /*
123  * vm_object_lock	A lock covering byte ranges within a VM object
124  *
125  */
126 struct vm_object_lock {
127 	struct vm_object_lock *next;
128 	int	type;			/* type of lock */
129 	int	waiting;		/* someone is waiting on the lock */
130 	off_t	base;			/* byte offset into object */
131 	off_t	bytes;			/* extent in bytes */
132 };
133 
134 #define VMOBJ_LOCK_SHARED	1
135 #define VMOBJ_LOCK_EXCL		2
136 
137 /*
138  * vm_object		A VM object which represents an arbitrarily sized
139  *			data store.
140  */
141 struct vm_object {
142 	TAILQ_ENTRY(vm_object) object_list; /* list of all objects */
143 	LIST_HEAD(, vm_object) shadow_head; /* objects that this is a shadow for */
144 	LIST_ENTRY(vm_object) shadow_list; /* chain of shadow objects */
145 	RB_HEAD(vm_page_rb_tree, vm_page) rb_memq;	/* resident pages */
146 	int generation;			/* generation ID */
147 	vm_size_t size;			/* Object size */
148 	int ref_count;			/* How many refs?? */
149 	int shadow_count;		/* how many objects that this is a shadow for */
150 	int hash_rand;			/* vm hash table randomizer	*/
151 	objtype_t type;			/* type of pager */
152 	u_short flags;			/* see below */
153 	u_short pg_color;		/* color of first page in obj */
154 	u_short paging_in_progress;	/* Paging (in or out) so don't collapse or destroy */
155 	int resident_page_count;	/* number of resident pages */
156 	struct vm_object *backing_object; /* object that I'm a shadow of */
157 	vm_ooffset_t backing_object_offset;/* Offset in backing object */
158 	TAILQ_ENTRY(vm_object) pager_object_list; /* list of all objects of this pager type */
159 	void *handle;
160 	vm_object_lock_t range_locks;
161 	union {
162 		/*
163 		 * Device pager
164 		 *
165 		 *	devp_pglist - list of allocated pages
166 		 */
167 		struct {
168 			TAILQ_HEAD(, vm_page) devp_pglist;
169 		} devp;
170 	} un_pager;
171 
172 	/*
173 	 * OBJT_SWAP and OBJT_VNODE VM objects may have swap backing
174 	 * store.  For vnodes the swap backing store acts as a fast
175 	 * data cache but the vnode contains the official data.
176 	 */
177 	RB_HEAD(swblock_rb_tree, swblock) swblock_root;
178 	int	swblock_count;
179 };
180 
181 /*
182  * Flags
183  */
184 #define OBJ_ACTIVE	0x0004		/* active objects */
185 #define OBJ_DEAD	0x0008		/* dead objects (during rundown) */
186 #define	OBJ_NOSPLIT	0x0010		/* dont split this object */
187 #define OBJ_PIPWNT	0x0040		/* paging in progress wanted */
188 #define	OBJ_WRITEABLE	0x0080		/* object has been made writable */
189 #define OBJ_MIGHTBEDIRTY 0x0100		/* object might be dirty */
190 #define OBJ_CLEANING	0x0200
191 #define OBJ_DEADWNT	0x1000		/* waiting because object is dead */
192 #define	OBJ_ONEMAPPING	0x2000		/* One USE (a single, non-forked) mapping flag */
193 
194 #define IDX_TO_OFF(idx) (((vm_ooffset_t)(idx)) << PAGE_SHIFT)
195 #define OFF_TO_IDX(off) ((vm_pindex_t)(((vm_ooffset_t)(off)) >> PAGE_SHIFT))
196 
197 #ifdef	_KERNEL
198 
199 #define OBJPC_SYNC	0x1			/* sync I/O */
200 #define OBJPC_INVAL	0x2			/* invalidate */
201 #define OBJPC_NOSYNC	0x4			/* skip if PG_NOSYNC */
202 
203 TAILQ_HEAD(object_q, vm_object);
204 
205 extern struct object_q vm_object_list;	/* list of allocated objects */
206 
207  /* lock for object list and count */
208 
209 extern struct vm_object kernel_object;	/* the single kernel object */
210 
211 #endif				/* _KERNEL */
212 
213 #ifdef _KERNEL
214 
215 static __inline void
216 vm_object_set_flag(vm_object_t object, u_int bits)
217 {
218 	atomic_set_short(&object->flags, bits);
219 }
220 
221 static __inline void
222 vm_object_clear_flag(vm_object_t object, u_int bits)
223 {
224 	atomic_clear_short(&object->flags, bits);
225 }
226 
227 static __inline void
228 vm_object_pip_add(vm_object_t object, int i)
229 {
230 	atomic_add_short(&object->paging_in_progress, i);
231 }
232 
233 static __inline void
234 vm_object_pip_subtract(vm_object_t object, int i)
235 {
236 	atomic_subtract_short(&object->paging_in_progress, i);
237 }
238 
239 static __inline void
240 vm_object_pip_wakeup(vm_object_t object)
241 {
242 	atomic_subtract_short(&object->paging_in_progress, 1);
243 	if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
244 		vm_object_clear_flag(object, OBJ_PIPWNT);
245 		wakeup(object);
246 	}
247 }
248 
249 static __inline void
250 vm_object_pip_wakeupn(vm_object_t object, int i)
251 {
252 	if (i)
253 		atomic_subtract_short(&object->paging_in_progress, i);
254 	if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
255 		vm_object_clear_flag(object, OBJ_PIPWNT);
256 		wakeup(object);
257 	}
258 }
259 
260 static __inline void
261 vm_object_pip_sleep(vm_object_t object, char *waitid)
262 {
263 	if (object->paging_in_progress) {
264 		crit_enter();
265 		if (object->paging_in_progress) {
266 			vm_object_set_flag(object, OBJ_PIPWNT);
267 			tsleep(object, 0, waitid, 0);
268 		}
269 		crit_exit();
270 	}
271 }
272 
273 static __inline void
274 vm_object_pip_wait(vm_object_t object, char *waitid)
275 {
276 	while (object->paging_in_progress)
277 		vm_object_pip_sleep(object, waitid);
278 }
279 
280 vm_object_t vm_object_allocate (objtype_t, vm_size_t);
281 void _vm_object_allocate (objtype_t, vm_size_t, vm_object_t);
282 boolean_t vm_object_coalesce (vm_object_t, vm_pindex_t, vm_size_t, vm_size_t);
283 void vm_object_collapse (vm_object_t);
284 void vm_object_deallocate (vm_object_t);
285 void vm_object_terminate (vm_object_t);
286 void vm_object_set_writeable_dirty (vm_object_t);
287 void vm_object_init (void);
288 void vm_object_page_clean (vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t);
289 void vm_object_page_remove (vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t);
290 void vm_object_pmap_copy (vm_object_t, vm_pindex_t, vm_pindex_t);
291 void vm_object_pmap_copy_1 (vm_object_t, vm_pindex_t, vm_pindex_t);
292 void vm_object_pmap_remove (vm_object_t, vm_pindex_t, vm_pindex_t);
293 void vm_object_reference (vm_object_t);
294 void vm_object_shadow (vm_object_t *, vm_ooffset_t *, vm_size_t);
295 void vm_object_madvise (vm_object_t, vm_pindex_t, int, int);
296 void vm_object_init2 (void);
297 vm_page_t vm_fault_object_page(vm_object_t, vm_ooffset_t, vm_prot_t, int, int *);
298 void vm_object_dead_sleep(vm_object_t, const char *);
299 void vm_object_dead_wakeup(vm_object_t);
300 
301 #endif				/* _KERNEL */
302 
303 #endif				/* _VM_VM_OBJECT_H_ */
304