vm_object.h revision 76827
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: head/sys/vm/vm_object.h 76827 2001-05-19 01:28:09Z alfred $
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#include <machine/atomic.h>
76
77enum obj_type { OBJT_DEFAULT, OBJT_SWAP, OBJT_VNODE, OBJT_DEVICE, OBJT_PHYS,
78		OBJT_DEAD };
79typedef u_char objtype_t;
80
81/*
82 *	Types defined:
83 *
84 *	vm_object_t		Virtual memory object.
85 *
86 */
87
88struct vm_object {
89	TAILQ_ENTRY(vm_object) object_list; /* list of all objects */
90	TAILQ_HEAD(, vm_object) shadow_head; /* objects that this is a shadow for */
91	TAILQ_ENTRY(vm_object) shadow_list; /* chain of shadow objects */
92	TAILQ_HEAD(, vm_page) memq;	/* list of resident pages */
93	int generation;			/* generation ID */
94	vm_size_t size;			/* Object size */
95	int ref_count;			/* How many refs?? */
96	int shadow_count;		/* how many objects that this is a shadow for */
97	int hash_rand;			/* vm hash table randomizer	*/
98	objtype_t type;			/* type of pager */
99	u_short flags;			/* see below */
100	u_short pg_color;		/* color of first page in obj */
101	u_short paging_in_progress;	/* Paging (in or out) so don't collapse or destroy */
102	int resident_page_count;	/* number of resident pages */
103	struct vm_object *backing_object; /* object that I'm a shadow of */
104	vm_ooffset_t backing_object_offset;/* Offset in backing object */
105	TAILQ_ENTRY(vm_object) pager_object_list; /* list of all objects of this pager type */
106	void *handle;
107	union {
108		/*
109		 * VNode pager
110		 *
111		 *	vnp_size - current size of file
112		 */
113		struct {
114			off_t vnp_size;
115		} vnp;
116
117		/*
118		 * Device pager
119		 *
120		 *	devp_pglist - list of allocated pages
121		 */
122		struct {
123			TAILQ_HEAD(, vm_page) devp_pglist;
124		} devp;
125
126		/*
127		 * Swap pager
128		 *
129		 *	swp_bcount - number of swap 'swblock' metablocks, each
130		 *		     contains up to 16 swapblk assignments.
131		 *		     see vm/swap_pager.h
132		 */
133		struct {
134			int swp_bcount;
135		} swp;
136	} un_pager;
137};
138
139/*
140 * Flags
141 */
142#define OBJ_ACTIVE	0x0004		/* active objects */
143#define OBJ_DEAD	0x0008		/* dead objects (during rundown) */
144#define	OBJ_NOSPLIT	0x0010		/* dont split this object */
145#define OBJ_PIPWNT	0x0040		/* paging in progress wanted */
146#define	OBJ_WRITEABLE	0x0080		/* object has been made writable */
147#define OBJ_MIGHTBEDIRTY 0x0100		/* object might be dirty */
148#define OBJ_CLEANING	0x0200
149#define OBJ_OPT		0x1000		/* I/O optimization */
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
161TAILQ_HEAD(object_q, vm_object);
162
163extern struct object_q vm_object_list;	/* list of allocated objects */
164
165extern vm_object_t kernel_object;	/* the single kernel object */
166extern vm_object_t kmem_object;
167
168#endif				/* _KERNEL */
169
170#ifdef _KERNEL
171
172/*
173 * For now a global vm lock.
174 */
175#define	VM_OBJECT_MTX(object)	(&vm_mtx)
176
177static __inline void
178vm_object_set_flag(vm_object_t object, u_short bits)
179{
180
181	mtx_assert(VM_OBJECT_MTX(object), MA_OWNED);
182	object->flags |= bits;
183}
184
185static __inline void
186vm_object_clear_flag(vm_object_t object, u_short bits)
187{
188
189	mtx_assert(VM_OBJECT_MTX(object), MA_OWNED);
190	object->flags &= ~bits;
191}
192
193static __inline void
194vm_object_pip_add(vm_object_t object, short i)
195{
196
197	mtx_assert(VM_OBJECT_MTX(object), MA_OWNED);
198	object->paging_in_progress += i;
199}
200
201static __inline void
202vm_object_pip_subtract(vm_object_t object, short i)
203{
204
205	mtx_assert(VM_OBJECT_MTX(object), MA_OWNED);
206	object->paging_in_progress -= i;
207}
208
209static __inline void
210vm_object_pip_wakeup(vm_object_t object)
211{
212
213	mtx_assert(VM_OBJECT_MTX(object), MA_OWNED);
214	object->paging_in_progress--;
215	if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
216		vm_object_clear_flag(object, OBJ_PIPWNT);
217		wakeup(object);
218	}
219}
220
221static __inline void
222vm_object_pip_wakeupn(vm_object_t object, short i)
223{
224
225	mtx_assert(VM_OBJECT_MTX(object), MA_OWNED);
226	if (i)
227		object->paging_in_progress -= i;
228	if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
229		vm_object_clear_flag(object, OBJ_PIPWNT);
230		wakeup(object);
231	}
232}
233
234static __inline void
235vm_object_pip_sleep(vm_object_t object, char *waitid)
236{
237
238	mtx_assert(VM_OBJECT_MTX(object), MA_OWNED);
239	if (object->paging_in_progress) {
240		int s = splvm();
241		if (object->paging_in_progress) {
242			vm_object_set_flag(object, OBJ_PIPWNT);
243			msleep(object, VM_OBJECT_MTX(object), PVM, waitid, 0);
244		}
245		splx(s);
246	}
247}
248
249static __inline void
250vm_object_pip_wait(vm_object_t object, char *waitid)
251{
252
253	mtx_assert(VM_OBJECT_MTX(object), MA_OWNED);
254	while (object->paging_in_progress)
255		vm_object_pip_sleep(object, waitid);
256}
257
258vm_object_t vm_object_allocate __P((objtype_t, vm_size_t));
259void _vm_object_allocate __P((objtype_t, vm_size_t, vm_object_t));
260boolean_t vm_object_coalesce __P((vm_object_t, vm_pindex_t, vm_size_t, vm_size_t));
261void vm_object_collapse __P((vm_object_t));
262void vm_object_deallocate __P((vm_object_t));
263void vm_object_terminate __P((vm_object_t));
264void vm_object_vndeallocate __P((vm_object_t));
265void vm_object_init __P((void));
266void vm_object_page_clean __P((vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t));
267void vm_object_page_remove __P((vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t));
268void vm_object_pmap_copy __P((vm_object_t, vm_pindex_t, vm_pindex_t));
269void vm_object_pmap_copy_1 __P((vm_object_t, vm_pindex_t, vm_pindex_t));
270void vm_object_pmap_remove __P((vm_object_t, vm_pindex_t, vm_pindex_t));
271void vm_object_reference __P((vm_object_t));
272void vm_object_shadow __P((vm_object_t *, vm_ooffset_t *, vm_size_t));
273void vm_object_madvise __P((vm_object_t, vm_pindex_t, int, int));
274void vm_object_init2 __P((void));
275#endif				/* _KERNEL */
276
277#endif				/* _VM_OBJECT_ */
278