Error out if no volumes are specified instead of core-dumping.
[dragonfly.git] / sys / vm / vm_page.h
blobb0405c6d908f5a43555b06a6de4236f978069553
1 /*
2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
6 * The Mach Operating System project at Carnegie-Mellon University.
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.
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.
36 * from: @(#)vm_page.h 8.2 (Berkeley) 12/13/93
39 * Copyright (c) 1987, 1990 Carnegie-Mellon University.
40 * All rights reserved.
42 * Authors: Avadis Tevanian, Jr., Michael Wayne Young
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.
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.
54 * Carnegie Mellon requests users of this software to return to
56 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
57 * School of Computer Science
58 * Carnegie Mellon University
59 * Pittsburgh PA 15213-3890
61 * any improvements or extensions that they make and grant Carnegie the
62 * rights to redistribute these changes.
64 * $FreeBSD: src/sys/vm/vm_page.h,v 1.75.2.8 2002/03/06 01:07:09 dillon Exp $
65 * $DragonFly: src/sys/vm/vm_page.h,v 1.28 2008/05/09 07:24:48 dillon Exp $
69 * Resident memory system definitions.
72 #ifndef _VM_VM_PAGE_H_
73 #define _VM_VM_PAGE_H_
75 #if !defined(KLD_MODULE) && defined(_KERNEL)
76 #include "opt_vmpage.h"
77 #endif
79 #ifndef _SYS_TYPES_H_
80 #include <sys/types.h>
81 #endif
82 #ifndef _SYS_TREE_H_
83 #include <sys/tree.h>
84 #endif
85 #ifndef _MACHINE_PMAP_H_
86 #include <machine/pmap.h>
87 #endif
88 #ifndef _VM_PMAP_H_
89 #include <vm/pmap.h>
90 #endif
91 #ifndef _MACHINE_ATOMIC_H_
92 #include <machine/atomic.h>
93 #endif
95 #ifdef _KERNEL
97 #ifndef _SYS_SYSTM_H_
98 #include <sys/systm.h>
99 #endif
100 #ifndef _SYS_THREAD2_H_
101 #include <sys/thread2.h>
102 #endif
104 #endif
106 typedef enum vm_page_event { VMEVENT_NONE, VMEVENT_COW } vm_page_event_t;
108 struct vm_page_action {
109 LIST_ENTRY(vm_page_action) entry;
110 vm_page_event_t event;
111 void (*func)(struct vm_page *,
112 struct vm_page_action *);
113 void *data;
116 typedef struct vm_page_action *vm_page_action_t;
119 * Management of resident (logical) pages.
121 * A small structure is kept for each resident
122 * page, indexed by page number. Each structure
123 * is an element of several lists:
125 * A hash table bucket used to quickly
126 * perform object/offset lookups
128 * A list of all pages for a given object,
129 * so they can be quickly deactivated at
130 * time of deallocation.
132 * An ordered list of pages due for pageout.
134 * In addition, the structure contains the object
135 * and offset to which this page belongs (for pageout),
136 * and sundry status bits.
138 * Fields in this structure are locked either by the lock on the
139 * object that the page belongs to (O) or by the lock on the page
140 * queues (P).
142 * The 'valid' and 'dirty' fields are distinct. A page may have dirty
143 * bits set without having associated valid bits set. This is used by
144 * NFS to implement piecemeal writes.
147 TAILQ_HEAD(pglist, vm_page);
149 struct msf_buf;
150 struct vm_object;
152 int rb_vm_page_compare(struct vm_page *, struct vm_page *);
154 struct vm_page_rb_tree;
155 RB_PROTOTYPE2(vm_page_rb_tree, vm_page, rb_entry, rb_vm_page_compare, vm_pindex_t);
157 struct vm_page {
158 TAILQ_ENTRY(vm_page) pageq; /* vm_page_queues[] list (P) */
159 RB_ENTRY(vm_page) rb_entry; /* Red-Black tree based at object */
161 struct vm_object *object; /* which object am I in (O,P)*/
162 vm_pindex_t pindex; /* offset into object (O,P) */
163 vm_paddr_t phys_addr; /* physical address of page */
164 struct md_page md; /* machine dependant stuff */
165 u_short queue; /* page queue index */
166 u_short flags; /* see below */
167 u_short pc; /* page color */
168 u_char act_count; /* page usage count */
169 u_char busy; /* page busy count */
170 u_int wire_count; /* wired down maps refs (P) */
171 int hold_count; /* page hold count */
174 * NOTE that these must support one bit per DEV_BSIZE in a page!!!
175 * so, on normal X86 kernels, they must be at least 8 bits wide.
177 #if PAGE_SIZE == 4096
178 u_char valid; /* map of valid DEV_BSIZE chunks */
179 u_char dirty; /* map of dirty DEV_BSIZE chunks */
180 #elif PAGE_SIZE == 8192
181 u_short valid; /* map of valid DEV_BSIZE chunks */
182 u_short dirty; /* map of dirty DEV_BSIZE chunks */
183 #endif
184 struct msf_buf *msf_hint; /* first page of an msfbuf map */
185 LIST_HEAD(,vm_page_action) action_list;
188 #ifndef __VM_PAGE_T_DEFINED__
189 #define __VM_PAGE_T_DEFINED__
190 typedef struct vm_page *vm_page_t;
191 #endif
194 * note: currently use SWAPBLK_NONE as an absolute value rather then
195 * a flag bit.
197 #define SWAPBLK_MASK ((daddr_t)((u_daddr_t)-1 >> 1)) /* mask */
198 #define SWAPBLK_NONE ((daddr_t)((u_daddr_t)SWAPBLK_MASK + 1))/* flag */
201 * Page coloring parameters. We default to a middle of the road optimization.
202 * Larger selections would not really hurt us but if a machine does not have
203 * a lot of memory it could cause vm_page_alloc() to eat more cpu cycles
204 * looking for free pages.
206 * Page coloring cannot be disabled. Modules do not have access to most PQ
207 * constants because they can change between builds.
209 #if defined(_KERNEL) && !defined(KLD_MODULE)
211 #if !defined(PQ_CACHESIZE)
212 #define PQ_CACHESIZE 256 /* max is 1024 (MB) */
213 #endif
215 #if PQ_CACHESIZE >= 1024
216 #define PQ_PRIME1 31 /* Prime number somewhat less than PQ_HASH_SIZE */
217 #define PQ_PRIME2 23 /* Prime number somewhat less than PQ_HASH_SIZE */
218 #define PQ_L2_SIZE 256 /* A number of colors opt for 1M cache */
220 #elif PQ_CACHESIZE >= 512
221 #define PQ_PRIME1 31 /* Prime number somewhat less than PQ_HASH_SIZE */
222 #define PQ_PRIME2 23 /* Prime number somewhat less than PQ_HASH_SIZE */
223 #define PQ_L2_SIZE 128 /* A number of colors opt for 512K cache */
225 #elif PQ_CACHESIZE >= 256
226 #define PQ_PRIME1 13 /* Prime number somewhat less than PQ_HASH_SIZE */
227 #define PQ_PRIME2 7 /* Prime number somewhat less than PQ_HASH_SIZE */
228 #define PQ_L2_SIZE 64 /* A number of colors opt for 256K cache */
230 #elif PQ_CACHESIZE >= 128
231 #define PQ_PRIME1 9 /* Produces a good PQ_L2_SIZE/3 + PQ_PRIME1 */
232 #define PQ_PRIME2 5 /* Prime number somewhat less than PQ_HASH_SIZE */
233 #define PQ_L2_SIZE 32 /* A number of colors opt for 128k cache */
235 #else
236 #define PQ_PRIME1 5 /* Prime number somewhat less than PQ_HASH_SIZE */
237 #define PQ_PRIME2 3 /* Prime number somewhat less than PQ_HASH_SIZE */
238 #define PQ_L2_SIZE 16 /* A reasonable number of colors (opt for 64K cache) */
240 #endif
242 #define PQ_L2_MASK (PQ_L2_SIZE - 1)
244 #endif /* KERNEL && !KLD_MODULE */
248 * The queue array is always based on PQ_MAXL2_SIZE regardless of the actual
249 * cache size chosen in order to present a uniform interface for modules.
251 #define PQ_MAXL2_SIZE 256 /* fixed maximum (in pages) / module compat */
253 #if PQ_L2_SIZE > PQ_MAXL2_SIZE
254 #error "Illegal PQ_L2_SIZE"
255 #endif
257 #define PQ_NONE 0
258 #define PQ_FREE 1
259 #define PQ_INACTIVE (1 + 1*PQ_MAXL2_SIZE)
260 #define PQ_ACTIVE (2 + 1*PQ_MAXL2_SIZE)
261 #define PQ_CACHE (3 + 1*PQ_MAXL2_SIZE)
262 #define PQ_HOLD (3 + 2*PQ_MAXL2_SIZE)
263 #define PQ_COUNT (4 + 2*PQ_MAXL2_SIZE)
266 * Scan support
268 struct vm_map;
270 struct rb_vm_page_scan_info {
271 vm_pindex_t start_pindex;
272 vm_pindex_t end_pindex;
273 int limit;
274 int desired;
275 int error;
276 int pagerflags;
277 vm_offset_t addr;
278 vm_pindex_t backing_offset_index;
279 struct vm_object *object;
280 struct vm_object *backing_object;
281 struct vm_page *mpte;
282 struct pmap *pmap;
283 struct vm_map *map;
286 int rb_vm_page_scancmp(struct vm_page *, void *);
288 struct vpgqueues {
289 struct pglist pl;
290 int *cnt;
291 int lcnt;
292 int flipflop; /* probably not the best place */
295 extern struct vpgqueues vm_page_queues[PQ_COUNT];
298 * These are the flags defined for vm_page.
300 * PG_UNMANAGED (used by OBJT_PHYS) indicates that the page is
301 * not under PV management but otherwise should be treated as a
302 * normal page. Pages not under PV management cannot be paged out
303 * via the object/vm_page_t because there is no knowledge of their
304 * pte mappings, nor can they be removed from their objects via
305 * the object, and such pages are also not on any PQ queue. The
306 * PG_MAPPED and PG_WRITEABLE flags are not applicable.
308 * PG_MAPPED only applies to managed pages, indicating whether the page
309 * is mapped onto one or more pmaps. A page might still be mapped to
310 * special pmaps in an unmanaged fashion, for example when mapped into a
311 * buffer cache buffer, without setting PG_MAPPED.
313 * PG_WRITEABLE indicates that there may be a writeable managed pmap entry
314 * somewhere, and that the page can be dirtied by hardware at any time
315 * and may have to be tested for that. The modified bit in unmanaged
316 * mappings or in the special clean map is not tested.
318 #define PG_BUSY 0x0001 /* page is in transit (O) */
319 #define PG_WANTED 0x0002 /* someone is waiting for page (O) */
320 #define PG_WINATCFLS 0x0004 /* flush dirty page on inactive q */
321 #define PG_FICTITIOUS 0x0008 /* physical page doesn't exist (O) */
322 #define PG_WRITEABLE 0x0010 /* page is writeable */
323 #define PG_MAPPED 0x0020 /* page is mapped (managed) */
324 #define PG_ZERO 0x0040 /* page is zeroed */
325 #define PG_REFERENCED 0x0080 /* page has been referenced */
326 #define PG_CLEANCHK 0x0100 /* page will be checked for cleaning */
327 #define PG_SWAPINPROG 0x0200 /* swap I/O in progress on page */
328 #define PG_NOSYNC 0x0400 /* do not collect for syncer */
329 #define PG_UNMANAGED 0x0800 /* No PV management for page */
330 #define PG_MARKER 0x1000 /* special queue marker page */
333 * Misc constants.
336 #define ACT_DECLINE 1
337 #define ACT_ADVANCE 3
338 #define ACT_INIT 5
339 #define ACT_MAX 64
341 #ifdef _KERNEL
343 * Each pageable resident page falls into one of four lists:
345 * free
346 * Available for allocation now.
348 * The following are all LRU sorted:
350 * cache
351 * Almost available for allocation. Still in an
352 * object, but clean and immediately freeable at
353 * non-interrupt times.
355 * inactive
356 * Low activity, candidates for reclamation.
357 * This is the list of pages that should be
358 * paged out next.
360 * active
361 * Pages that are "active" i.e. they have been
362 * recently referenced.
364 * zero
365 * Pages that are really free and have been pre-zeroed
369 extern int vm_page_zero_count;
370 extern struct vm_page *vm_page_array; /* First resident page in table */
371 extern int vm_page_array_size; /* number of vm_page_t's */
372 extern long first_page; /* first physical page number */
374 #define VM_PAGE_TO_PHYS(entry) \
375 ((entry)->phys_addr)
377 #define PHYS_TO_VM_PAGE(pa) \
378 (&vm_page_array[atop(pa) - first_page])
381 * Functions implemented as macros
384 static __inline void
385 vm_page_flag_set(vm_page_t m, unsigned int bits)
387 atomic_set_short(&(m)->flags, bits);
390 static __inline void
391 vm_page_flag_clear(vm_page_t m, unsigned int bits)
393 atomic_clear_short(&(m)->flags, bits);
396 static __inline void
397 vm_page_busy(vm_page_t m)
399 KASSERT((m->flags & PG_BUSY) == 0,
400 ("vm_page_busy: page already busy!!!"));
401 vm_page_flag_set(m, PG_BUSY);
405 * vm_page_flash:
407 * wakeup anyone waiting for the page.
410 static __inline void
411 vm_page_flash(vm_page_t m)
413 if (m->flags & PG_WANTED) {
414 vm_page_flag_clear(m, PG_WANTED);
415 wakeup(m);
420 * Clear the PG_BUSY flag and wakeup anyone waiting for the page. This
421 * is typically the last call you make on a page before moving onto
422 * other things.
424 static __inline void
425 vm_page_wakeup(vm_page_t m)
427 KASSERT(m->flags & PG_BUSY, ("vm_page_wakeup: page not busy!!!"));
428 vm_page_flag_clear(m, PG_BUSY);
429 vm_page_flash(m);
433 * These routines manipulate the 'soft busy' count for a page. A soft busy
434 * is almost like PG_BUSY except that it allows certain compatible operations
435 * to occur on the page while it is busy. For example, a page undergoing a
436 * write can still be mapped read-only.
438 static __inline void
439 vm_page_io_start(vm_page_t m)
441 atomic_add_char(&(m)->busy, 1);
444 static __inline void
445 vm_page_io_finish(vm_page_t m)
447 atomic_subtract_char(&m->busy, 1);
448 if (m->busy == 0)
449 vm_page_flash(m);
453 #if PAGE_SIZE == 4096
454 #define VM_PAGE_BITS_ALL 0xff
455 #endif
457 #if PAGE_SIZE == 8192
458 #define VM_PAGE_BITS_ALL 0xffff
459 #endif
462 * Note: the code will always use nominally free pages from the free list
463 * before trying other flag-specified sources.
465 * At least one of VM_ALLOC_NORMAL|VM_ALLOC_SYSTEM|VM_ALLOC_INTERRUPT
466 * must be specified. VM_ALLOC_RETRY may only be specified if VM_ALLOC_NORMAL
467 * is also specified.
469 #define VM_ALLOC_NORMAL 0x01 /* ok to use cache pages */
470 #define VM_ALLOC_SYSTEM 0x02 /* ok to exhaust most of free list */
471 #define VM_ALLOC_INTERRUPT 0x04 /* ok to exhaust entire free list */
472 #define VM_ALLOC_ZERO 0x08 /* req pre-zero'd memory if avail */
473 #define VM_ALLOC_RETRY 0x80 /* indefinite block (vm_page_grab()) */
475 void vm_page_unhold(vm_page_t mem);
476 void vm_page_activate (vm_page_t);
477 vm_page_t vm_page_alloc (struct vm_object *, vm_pindex_t, int);
478 vm_page_t vm_page_grab (struct vm_object *, vm_pindex_t, int);
479 void vm_page_cache (vm_page_t);
480 int vm_page_try_to_cache (vm_page_t);
481 int vm_page_try_to_free (vm_page_t);
482 void vm_page_dontneed (vm_page_t);
483 void vm_page_deactivate (vm_page_t);
484 void vm_page_insert (vm_page_t, struct vm_object *, vm_pindex_t);
485 vm_page_t vm_page_lookup (struct vm_object *, vm_pindex_t);
486 void vm_page_remove (vm_page_t);
487 void vm_page_rename (vm_page_t, struct vm_object *, vm_pindex_t);
488 vm_offset_t vm_page_startup (vm_offset_t);
489 vm_page_t vm_add_new_page (vm_paddr_t pa);
490 void vm_page_unmanage (vm_page_t);
491 void vm_page_unwire (vm_page_t, int);
492 void vm_page_wire (vm_page_t);
493 void vm_page_unqueue (vm_page_t);
494 void vm_page_unqueue_nowakeup (vm_page_t);
495 void vm_page_set_validclean (vm_page_t, int, int);
496 void vm_page_set_dirty (vm_page_t, int, int);
497 void vm_page_clear_dirty (vm_page_t, int, int);
498 void vm_page_set_invalid (vm_page_t, int, int);
499 int vm_page_is_valid (vm_page_t, int, int);
500 void vm_page_test_dirty (vm_page_t);
501 int vm_page_bits (int, int);
502 vm_page_t vm_page_list_find(int basequeue, int index, boolean_t prefer_zero);
503 void vm_page_zero_invalid(vm_page_t m, boolean_t setvalid);
504 void vm_page_free_toq(vm_page_t m);
505 vm_offset_t vm_contig_pg_kmap(int, u_long, vm_map_t, int);
506 void vm_contig_pg_free(int, u_long);
507 void vm_page_event_internal(vm_page_t, vm_page_event_t);
508 void vm_page_dirty(vm_page_t m);
511 * Holding a page keeps it from being reused. Other parts of the system
512 * can still disassociate the page from its current object and free it, or
513 * perform read or write I/O on it and/or otherwise manipulate the page,
514 * but if the page is held the VM system will leave the page and its data
515 * intact and not reuse the page for other purposes until the last hold
516 * reference is released. (see vm_page_wire() if you want to prevent the
517 * page from being disassociated from its object too).
519 * This routine must be called while at splvm() or better.
521 * The caller must still validate the contents of the page and, if necessary,
522 * wait for any pending I/O (e.g. vm_page_sleep_busy() loop) to complete
523 * before manipulating the page.
525 static __inline void
526 vm_page_hold(vm_page_t mem)
528 mem->hold_count++;
532 * Reduce the protection of a page. This routine never raises the
533 * protection and therefore can be safely called if the page is already
534 * at VM_PROT_NONE (it will be a NOP effectively ).
536 * VM_PROT_NONE will remove all user mappings of a page. This is often
537 * necessary when a page changes state (for example, turns into a copy-on-write
538 * page or needs to be frozen for write I/O) in order to force a fault, or
539 * to force a page's dirty bits to be synchronized and avoid hardware
540 * (modified/accessed) bit update races with pmap changes.
542 * Since 'prot' is usually a constant, this inline usually winds up optimizing
543 * out the primary conditional.
545 * WARNING: VM_PROT_NONE can block, but will loop until all mappings have
546 * been cleared. Callers should be aware that other page related elements
547 * might have changed, however.
549 static __inline void
550 vm_page_protect(vm_page_t mem, int prot)
552 if (prot == VM_PROT_NONE) {
553 if (mem->flags & (PG_WRITEABLE|PG_MAPPED)) {
554 pmap_page_protect(mem, VM_PROT_NONE);
555 /* PG_WRITEABLE & PG_MAPPED cleared by call */
557 } else if ((prot == VM_PROT_READ) && (mem->flags & PG_WRITEABLE)) {
558 pmap_page_protect(mem, VM_PROT_READ);
559 /* PG_WRITEABLE cleared by call */
564 * Zero-fill the specified page. The entire contents of the page will be
565 * zero'd out.
567 static __inline boolean_t
568 vm_page_zero_fill(vm_page_t m)
570 pmap_zero_page(VM_PAGE_TO_PHYS(m));
571 return (TRUE);
575 * Copy the contents of src_m to dest_m. The pages must be stable but spl
576 * and other protections depend on context.
578 static __inline void
579 vm_page_copy(vm_page_t src_m, vm_page_t dest_m)
581 pmap_copy_page(VM_PAGE_TO_PHYS(src_m), VM_PAGE_TO_PHYS(dest_m));
582 dest_m->valid = VM_PAGE_BITS_ALL;
583 dest_m->dirty = VM_PAGE_BITS_ALL;
587 * Free a page. The page must be marked BUSY.
589 * The clearing of PG_ZERO is a temporary safety until the code can be
590 * reviewed to determine that PG_ZERO is being properly cleared on
591 * write faults or maps. PG_ZERO was previously cleared in
592 * vm_page_alloc().
594 static __inline void
595 vm_page_free(vm_page_t m)
597 vm_page_flag_clear(m, PG_ZERO);
598 vm_page_free_toq(m);
602 * Free a page to the zerod-pages queue
604 static __inline void
605 vm_page_free_zero(vm_page_t m)
607 vm_page_flag_set(m, PG_ZERO);
608 vm_page_free_toq(m);
612 * Wait until page is no longer PG_BUSY or (if also_m_busy is TRUE)
613 * m->busy is zero. Returns TRUE if it had to sleep ( including if
614 * it almost had to sleep and made temporary spl*() mods), FALSE
615 * otherwise.
617 * This routine assumes that interrupts can only remove the busy
618 * status from a page, not set the busy status or change it from
619 * PG_BUSY to m->busy or vise versa (which would create a timing
620 * window).
622 * Note: as an inline, 'also_m_busy' is usually a constant and well
623 * optimized.
625 static __inline int
626 vm_page_sleep_busy(vm_page_t m, int also_m_busy, const char *msg)
628 if ((m->flags & PG_BUSY) || (also_m_busy && m->busy)) {
629 crit_enter();
630 if ((m->flags & PG_BUSY) || (also_m_busy && m->busy)) {
632 * Page is busy. Wait and retry.
634 vm_page_flag_set(m, PG_WANTED | PG_REFERENCED);
635 tsleep(m, 0, msg, 0);
637 crit_exit();
638 return(TRUE);
639 /* not reached */
641 return(FALSE);
645 * Set page to not be dirty. Note: does not clear pmap modify bits .
647 static __inline void
648 vm_page_undirty(vm_page_t m)
650 m->dirty = 0;
653 #endif /* _KERNEL */
654 #endif /* !_VM_VM_PAGE_H_ */