FreeBSD/Linux Kernel Cross Reference
sys/vm/vm_object.h
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: releng/10.0/sys/vm/vm_object.h 254141 2013-08-09 11:28:55Z attilio $
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 #include <sys/_rwlock.h>
74
75 #include <vm/_vm_radix.h>
76
77 /*
78 * Types defined:
79 *
80 * vm_object_t Virtual memory object.
81 *
82 * The root of cached pages pool is protected by both the per-object lock
83 * and the free pages queue mutex.
84 * On insert in the cache radix trie, the per-object lock is expected
85 * to be already held and the free pages queue mutex will be
86 * acquired during the operation too.
87 * On remove and lookup from the cache radix trie, only the free
88 * pages queue mutex is expected to be locked.
89 * These rules allow for reliably checking for the presence of cached
90 * pages with only the per-object lock held, thereby reducing contention
91 * for the free pages queue mutex.
92 *
93 * List of locks
94 * (c) const until freed
95 * (o) per-object lock
96 * (f) free pages queue mutex
97 *
98 */
99
100 struct vm_object {
101 struct rwlock lock;
102 TAILQ_ENTRY(vm_object) object_list; /* list of all objects */
103 LIST_HEAD(, vm_object) shadow_head; /* objects that this is a shadow for */
104 LIST_ENTRY(vm_object) shadow_list; /* chain of shadow objects */
105 TAILQ_HEAD(respgs, vm_page) memq; /* list of resident pages */
106 struct vm_radix rtree; /* root of the resident page radix trie*/
107 vm_pindex_t size; /* Object size */
108 int generation; /* generation ID */
109 int ref_count; /* How many refs?? */
110 int shadow_count; /* how many objects that this is a shadow for */
111 vm_memattr_t memattr; /* default memory attribute for pages */
112 objtype_t type; /* type of pager */
113 u_short flags; /* see below */
114 u_short pg_color; /* (c) color of first page in obj */
115 u_int paging_in_progress; /* Paging (in or out) so don't collapse or destroy */
116 int resident_page_count; /* number of resident pages */
117 struct vm_object *backing_object; /* object that I'm a shadow of */
118 vm_ooffset_t backing_object_offset;/* Offset in backing object */
119 TAILQ_ENTRY(vm_object) pager_object_list; /* list of all objects of this pager type */
120 LIST_HEAD(, vm_reserv) rvq; /* list of reservations */
121 struct vm_radix cache; /* (o + f) root of the cache page radix trie */
122 void *handle;
123 union {
124 /*
125 * VNode pager
126 *
127 * vnp_size - current size of file
128 */
129 struct {
130 off_t vnp_size;
131 vm_ooffset_t writemappings;
132 } vnp;
133
134 /*
135 * Device pager
136 *
137 * devp_pglist - list of allocated pages
138 */
139 struct {
140 TAILQ_HEAD(, vm_page) devp_pglist;
141 struct cdev_pager_ops *ops;
142 struct cdev *dev;
143 } devp;
144
145 /*
146 * SG pager
147 *
148 * sgp_pglist - list of allocated pages
149 */
150 struct {
151 TAILQ_HEAD(, vm_page) sgp_pglist;
152 } sgp;
153
154 /*
155 * Swap pager
156 *
157 * swp_tmpfs - back-pointer to the tmpfs vnode,
158 * if any, which uses the vm object
159 * as backing store. The handle
160 * cannot be reused for linking,
161 * because the vnode can be
162 * reclaimed and recreated, making
163 * the handle changed and hash-chain
164 * invalid.
165 *
166 * swp_bcount - number of swap 'swblock' metablocks, each
167 * contains up to 16 swapblk assignments.
168 * see vm/swap_pager.h
169 */
170 struct {
171 void *swp_tmpfs;
172 int swp_bcount;
173 } swp;
174 } un_pager;
175 struct ucred *cred;
176 vm_ooffset_t charge;
177 };
178
179 /*
180 * Flags
181 */
182 #define OBJ_FICTITIOUS 0x0001 /* (c) contains fictitious pages */
183 #define OBJ_UNMANAGED 0x0002 /* (c) contains unmanaged pages */
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_MIGHTBEDIRTY 0x0100 /* object might be dirty, only for vnode */
189 #define OBJ_COLORED 0x1000 /* pg_color is defined */
190 #define OBJ_ONEMAPPING 0x2000 /* One USE (a single, non-forked) mapping flag */
191 #define OBJ_DISCONNECTWNT 0x4000 /* disconnect from vnode wanted */
192 #define OBJ_TMPFS 0x8000
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 /*
204 * The following options are supported by vm_object_page_remove().
205 */
206 #define OBJPR_CLEANONLY 0x1 /* Don't remove dirty pages. */
207 #define OBJPR_NOTMAPPED 0x2 /* Don't unmap pages. */
208 #define OBJPR_NOTWIRED 0x4 /* Don't remove wired pages. */
209
210 TAILQ_HEAD(object_q, vm_object);
211
212 extern struct object_q vm_object_list; /* list of allocated objects */
213 extern struct mtx vm_object_list_mtx; /* lock for object list and count */
214
215 extern struct vm_object kernel_object_store;
216 extern struct vm_object kmem_object_store;
217
218 #define kernel_object (&kernel_object_store)
219 #define kmem_object (&kmem_object_store)
220
221 #define VM_OBJECT_ASSERT_LOCKED(object) \
222 rw_assert(&(object)->lock, RA_LOCKED)
223 #define VM_OBJECT_ASSERT_RLOCKED(object) \
224 rw_assert(&(object)->lock, RA_RLOCKED)
225 #define VM_OBJECT_ASSERT_WLOCKED(object) \
226 rw_assert(&(object)->lock, RA_WLOCKED)
227 #define VM_OBJECT_LOCK_DOWNGRADE(object) \
228 rw_downgrade(&(object)->lock)
229 #define VM_OBJECT_RLOCK(object) \
230 rw_rlock(&(object)->lock)
231 #define VM_OBJECT_RUNLOCK(object) \
232 rw_runlock(&(object)->lock)
233 #define VM_OBJECT_SLEEP(object, wchan, pri, wmesg, timo) \
234 rw_sleep((wchan), &(object)->lock, (pri), (wmesg), (timo))
235 #define VM_OBJECT_TRYRLOCK(object) \
236 rw_try_rlock(&(object)->lock)
237 #define VM_OBJECT_TRYWLOCK(object) \
238 rw_try_wlock(&(object)->lock)
239 #define VM_OBJECT_WLOCK(object) \
240 rw_wlock(&(object)->lock)
241 #define VM_OBJECT_WUNLOCK(object) \
242 rw_wunlock(&(object)->lock)
243
244 /*
245 * The object must be locked or thread private.
246 */
247 static __inline void
248 vm_object_set_flag(vm_object_t object, u_short bits)
249 {
250
251 object->flags |= bits;
252 }
253
254 void vm_object_clear_flag(vm_object_t object, u_short bits);
255 void vm_object_pip_add(vm_object_t object, short i);
256 void vm_object_pip_subtract(vm_object_t object, short i);
257 void vm_object_pip_wakeup(vm_object_t object);
258 void vm_object_pip_wakeupn(vm_object_t object, short i);
259 void vm_object_pip_wait(vm_object_t object, char *waitid);
260
261 static __inline boolean_t
262 vm_object_cache_is_empty(vm_object_t object)
263 {
264
265 return (vm_radix_is_empty(&object->cache));
266 }
267
268 vm_object_t vm_object_allocate (objtype_t, vm_pindex_t);
269 boolean_t vm_object_coalesce(vm_object_t, vm_ooffset_t, vm_size_t, vm_size_t,
270 boolean_t);
271 void vm_object_collapse (vm_object_t);
272 void vm_object_deallocate (vm_object_t);
273 void vm_object_destroy (vm_object_t);
274 void vm_object_terminate (vm_object_t);
275 void vm_object_set_writeable_dirty (vm_object_t);
276 void vm_object_init (void);
277 void vm_object_madvise(vm_object_t, vm_pindex_t, vm_pindex_t, int);
278 void vm_object_page_cache(vm_object_t object, vm_pindex_t start,
279 vm_pindex_t end);
280 boolean_t vm_object_page_clean(vm_object_t object, vm_ooffset_t start,
281 vm_ooffset_t end, int flags);
282 void vm_object_page_remove(vm_object_t object, vm_pindex_t start,
283 vm_pindex_t end, int options);
284 boolean_t vm_object_populate(vm_object_t, vm_pindex_t, vm_pindex_t);
285 void vm_object_print(long addr, boolean_t have_addr, long count, char *modif);
286 void vm_object_reference (vm_object_t);
287 void vm_object_reference_locked(vm_object_t);
288 int vm_object_set_memattr(vm_object_t object, vm_memattr_t memattr);
289 void vm_object_shadow (vm_object_t *, vm_ooffset_t *, vm_size_t);
290 void vm_object_split(vm_map_entry_t);
291 boolean_t vm_object_sync(vm_object_t, vm_ooffset_t, vm_size_t, boolean_t,
292 boolean_t);
293 #endif /* _KERNEL */
294
295 #endif /* _VM_OBJECT_ */
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