xref: /dragonfly/sys/vm/vm_object.h (revision 8a7bdfea)
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 _MACHINE_ATOMIC_H_
85 #include <machine/atomic.h>
86 #endif
87 #ifndef _VM_VM_H_
88 #include <vm/vm.h>
89 #endif
90 #ifndef _VM_VM_PAGE_H_
91 #include <vm/vm_page.h>
92 #endif
93 
94 #ifdef _KERNEL
95 
96 #ifndef _SYS_THREAD2_H_
97 #include <sys/thread2.h>
98 #endif
99 
100 #endif
101 
102 enum obj_type {
103 	OBJT_DEFAULT,
104 	OBJT_SWAP,   	/* object backed by swap blocks */
105 	OBJT_VNODE, 	/* object backed by file pages (vnode) */
106 	OBJT_DEVICE, 	/* object backed by device pages */
107 	OBJT_PHYS,  	/* object backed by physical pages */
108 	OBJT_DEAD   	/* dead object */
109 };
110 typedef u_char objtype_t;
111 
112 /*
113  * vm_object_lock	A lock covering byte ranges within a VM object
114  *
115  */
116 struct vm_object_lock {
117 	struct vm_object_lock *next;
118 	int	type;			/* type of lock */
119 	int	waiting;		/* someone is waiting on the lock */
120 	off_t	base;			/* byte offset into object */
121 	off_t	bytes;			/* extent in bytes */
122 };
123 
124 #define VMOBJ_LOCK_SHARED	1
125 #define VMOBJ_LOCK_EXCL		2
126 
127 /*
128  * vm_object		A VM object which represents an arbitrarily sized
129  *			data store.
130  */
131 struct vm_object {
132 	TAILQ_ENTRY(vm_object) object_list; /* list of all objects */
133 	LIST_HEAD(, vm_object) shadow_head; /* objects that this is a shadow for */
134 	LIST_ENTRY(vm_object) shadow_list; /* chain of shadow objects */
135 	RB_HEAD(vm_page_rb_tree, vm_page) rb_memq;	/* resident pages */
136 	int generation;			/* generation ID */
137 	vm_size_t size;			/* Object size */
138 	int ref_count;			/* How many refs?? */
139 	int shadow_count;		/* how many objects that this is a shadow for */
140 	int hash_rand;			/* vm hash table randomizer	*/
141 	objtype_t type;			/* type of pager */
142 	u_short flags;			/* see below */
143 	u_short pg_color;		/* color of first page in obj */
144 	u_short paging_in_progress;	/* Paging (in or out) so don't collapse or destroy */
145 	int resident_page_count;	/* number of resident pages */
146 	struct vm_object *backing_object; /* object that I'm a shadow of */
147 	vm_ooffset_t backing_object_offset;/* Offset in backing object */
148 	TAILQ_ENTRY(vm_object) pager_object_list; /* list of all objects of this pager type */
149 	void *handle;
150 	vm_object_lock_t range_locks;
151 	union {
152 		/*
153 		 * Device pager
154 		 *
155 		 *	devp_pglist - list of allocated pages
156 		 */
157 		struct {
158 			TAILQ_HEAD(, vm_page) devp_pglist;
159 		} devp;
160 
161 		/*
162 		 * Swap pager
163 		 *
164 		 *	swp_bcount - number of swap 'swblock' metablocks, each
165 		 *		     contains up to 16 swapblk assignments.
166 		 *		     see vm/swap_pager.h
167 		 */
168 		struct {
169 			int swp_bcount;
170 		} swp;
171 	} un_pager;
172 };
173 
174 /*
175  * Flags
176  */
177 #define OBJ_ACTIVE	0x0004		/* active objects */
178 #define OBJ_DEAD	0x0008		/* dead objects (during rundown) */
179 #define	OBJ_NOSPLIT	0x0010		/* dont split this object */
180 #define OBJ_PIPWNT	0x0040		/* paging in progress wanted */
181 #define	OBJ_WRITEABLE	0x0080		/* object has been made writable */
182 #define OBJ_MIGHTBEDIRTY 0x0100		/* object might be dirty */
183 #define OBJ_CLEANING	0x0200
184 #define OBJ_DEADWNT	0x1000		/* waiting because object is dead */
185 #define	OBJ_ONEMAPPING	0x2000		/* One USE (a single, non-forked) mapping flag */
186 
187 #define IDX_TO_OFF(idx) (((vm_ooffset_t)(idx)) << PAGE_SHIFT)
188 #define OFF_TO_IDX(off) ((vm_pindex_t)(((vm_ooffset_t)(off)) >> PAGE_SHIFT))
189 
190 #ifdef	_KERNEL
191 
192 #define OBJPC_SYNC	0x1			/* sync I/O */
193 #define OBJPC_INVAL	0x2			/* invalidate */
194 #define OBJPC_NOSYNC	0x4			/* skip if PG_NOSYNC */
195 
196 TAILQ_HEAD(object_q, vm_object);
197 
198 extern struct object_q vm_object_list;	/* list of allocated objects */
199 
200  /* lock for object list and count */
201 
202 extern struct vm_object kernel_object;	/* the single kernel object */
203 
204 #endif				/* _KERNEL */
205 
206 #ifdef _KERNEL
207 
208 static __inline void
209 vm_object_set_flag(vm_object_t object, u_int bits)
210 {
211 	atomic_set_short(&object->flags, bits);
212 }
213 
214 static __inline void
215 vm_object_clear_flag(vm_object_t object, u_int bits)
216 {
217 	atomic_clear_short(&object->flags, bits);
218 }
219 
220 static __inline void
221 vm_object_pip_add(vm_object_t object, int i)
222 {
223 	atomic_add_short(&object->paging_in_progress, i);
224 }
225 
226 static __inline void
227 vm_object_pip_subtract(vm_object_t object, int i)
228 {
229 	atomic_subtract_short(&object->paging_in_progress, i);
230 }
231 
232 static __inline void
233 vm_object_pip_wakeup(vm_object_t object)
234 {
235 	atomic_subtract_short(&object->paging_in_progress, 1);
236 	if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
237 		vm_object_clear_flag(object, OBJ_PIPWNT);
238 		wakeup(object);
239 	}
240 }
241 
242 static __inline void
243 vm_object_pip_wakeupn(vm_object_t object, int i)
244 {
245 	if (i)
246 		atomic_subtract_short(&object->paging_in_progress, i);
247 	if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
248 		vm_object_clear_flag(object, OBJ_PIPWNT);
249 		wakeup(object);
250 	}
251 }
252 
253 static __inline void
254 vm_object_pip_sleep(vm_object_t object, char *waitid)
255 {
256 	if (object->paging_in_progress) {
257 		crit_enter();
258 		if (object->paging_in_progress) {
259 			vm_object_set_flag(object, OBJ_PIPWNT);
260 			tsleep(object, 0, waitid, 0);
261 		}
262 		crit_exit();
263 	}
264 }
265 
266 static __inline void
267 vm_object_pip_wait(vm_object_t object, char *waitid)
268 {
269 	while (object->paging_in_progress)
270 		vm_object_pip_sleep(object, waitid);
271 }
272 
273 vm_object_t vm_object_allocate (objtype_t, vm_size_t);
274 void _vm_object_allocate (objtype_t, vm_size_t, vm_object_t);
275 boolean_t vm_object_coalesce (vm_object_t, vm_pindex_t, vm_size_t, vm_size_t);
276 void vm_object_collapse (vm_object_t);
277 void vm_object_deallocate (vm_object_t);
278 void vm_object_terminate (vm_object_t);
279 void vm_object_set_writeable_dirty (vm_object_t);
280 void vm_object_init (void);
281 void vm_object_page_clean (vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t);
282 void vm_object_page_remove (vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t);
283 void vm_object_pmap_copy (vm_object_t, vm_pindex_t, vm_pindex_t);
284 void vm_object_pmap_copy_1 (vm_object_t, vm_pindex_t, vm_pindex_t);
285 void vm_object_pmap_remove (vm_object_t, vm_pindex_t, vm_pindex_t);
286 void vm_object_reference (vm_object_t);
287 void vm_object_shadow (vm_object_t *, vm_ooffset_t *, vm_size_t);
288 void vm_object_madvise (vm_object_t, vm_pindex_t, int, int);
289 void vm_object_init2 (void);
290 vm_page_t vm_fault_object_page(vm_object_t, vm_ooffset_t, vm_prot_t, int, int *);
291 void vm_object_dead_sleep(vm_object_t, const char *);
292 void vm_object_dead_wakeup(vm_object_t);
293 
294 #endif				/* _KERNEL */
295 
296 #endif				/* _VM_VM_OBJECT_H_ */
297