MP Implementation 1/2: Get the APIC code working again, sweetly integrate the
[dragonfly.git] / sys / vm / vm_object.c
CommitLineData
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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.c 8.5 (Berkeley) 3/22/94
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.c,v 1.171.2.8 2003/05/26 19:17:56 alc Exp $
8a8d5d85 65 * $DragonFly: src/sys/vm/vm_object.c,v 1.6 2003/07/06 21:23:56 dillon Exp $
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66 */
67
68/*
69 * Virtual memory object module.
70 */
71
72#include <sys/param.h>
73#include <sys/systm.h>
74#include <sys/proc.h> /* for curproc, pageproc */
75#include <sys/vnode.h>
76#include <sys/vmmeter.h>
77#include <sys/mman.h>
78#include <sys/mount.h>
79#include <sys/kernel.h>
80#include <sys/sysctl.h>
81
82#include <vm/vm.h>
83#include <vm/vm_param.h>
84#include <vm/pmap.h>
85#include <vm/vm_map.h>
86#include <vm/vm_object.h>
87#include <vm/vm_page.h>
88#include <vm/vm_pageout.h>
89#include <vm/vm_pager.h>
90#include <vm/swap_pager.h>
91#include <vm/vm_kern.h>
92#include <vm/vm_extern.h>
93#include <vm/vm_zone.h>
94
95#define EASY_SCAN_FACTOR 8
96
97#define MSYNC_FLUSH_HARDSEQ 0x01
98#define MSYNC_FLUSH_SOFTSEQ 0x02
99
100static int msync_flush_flags = MSYNC_FLUSH_HARDSEQ | MSYNC_FLUSH_SOFTSEQ;
101SYSCTL_INT(_vm, OID_AUTO, msync_flush_flags,
102 CTLFLAG_RW, &msync_flush_flags, 0, "");
103
104static void vm_object_qcollapse (vm_object_t object);
105static int vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int curgeneration, int pagerflags);
106
107/*
108 * Virtual memory objects maintain the actual data
109 * associated with allocated virtual memory. A given
110 * page of memory exists within exactly one object.
111 *
112 * An object is only deallocated when all "references"
113 * are given up. Only one "reference" to a given
114 * region of an object should be writeable.
115 *
116 * Associated with each object is a list of all resident
117 * memory pages belonging to that object; this list is
118 * maintained by the "vm_page" module, and locked by the object's
119 * lock.
120 *
121 * Each object also records a "pager" routine which is
122 * used to retrieve (and store) pages to the proper backing
123 * storage. In addition, objects may be backed by other
124 * objects from which they were virtual-copied.
125 *
126 * The only items within the object structure which are
127 * modified after time of creation are:
128 * reference count locked by object's lock
129 * pager routine locked by object's lock
130 *
131 */
132
133struct object_q vm_object_list;
8a8d5d85 134static struct lwkt_token vm_object_list_token;
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135static long vm_object_count; /* count of all objects */
136vm_object_t kernel_object;
137vm_object_t kmem_object;
138static struct vm_object kernel_object_store;
139static struct vm_object kmem_object_store;
140extern int vm_pageout_page_count;
141
142static long object_collapses;
143static long object_bypasses;
144static int next_index;
145static vm_zone_t obj_zone;
146static struct vm_zone obj_zone_store;
147static int object_hash_rand;
148#define VM_OBJECTS_INIT 256
149static struct vm_object vm_objects_init[VM_OBJECTS_INIT];
150
151void
152_vm_object_allocate(type, size, object)
153 objtype_t type;
154 vm_size_t size;
155 vm_object_t object;
156{
157 int incr;
158 TAILQ_INIT(&object->memq);
159 LIST_INIT(&object->shadow_head);
160
161 object->type = type;
162 object->size = size;
163 object->ref_count = 1;
164 object->flags = 0;
165 if ((object->type == OBJT_DEFAULT) || (object->type == OBJT_SWAP))
166 vm_object_set_flag(object, OBJ_ONEMAPPING);
167 object->paging_in_progress = 0;
168 object->resident_page_count = 0;
169 object->shadow_count = 0;
170 object->pg_color = next_index;
171 if ( size > (PQ_L2_SIZE / 3 + PQ_PRIME1))
172 incr = PQ_L2_SIZE / 3 + PQ_PRIME1;
173 else
174 incr = size;
175 next_index = (next_index + incr) & PQ_L2_MASK;
176 object->handle = NULL;
177 object->backing_object = NULL;
178 object->backing_object_offset = (vm_ooffset_t) 0;
179 /*
180 * Try to generate a number that will spread objects out in the
181 * hash table. We 'wipe' new objects across the hash in 128 page
182 * increments plus 1 more to offset it a little more by the time
183 * it wraps around.
184 */
185 object->hash_rand = object_hash_rand - 129;
186
187 object->generation++;
188
189 TAILQ_INSERT_TAIL(&vm_object_list, object, object_list);
190 vm_object_count++;
191 object_hash_rand = object->hash_rand;
192}
193
194/*
195 * vm_object_init:
196 *
197 * Initialize the VM objects module.
198 */
199void
200vm_object_init()
201{
202 TAILQ_INIT(&vm_object_list);
8a8d5d85 203 lwkt_inittoken(&vm_object_list_token);
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204 vm_object_count = 0;
205
206 kernel_object = &kernel_object_store;
207 _vm_object_allocate(OBJT_DEFAULT, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS),
208 kernel_object);
209
210 kmem_object = &kmem_object_store;
211 _vm_object_allocate(OBJT_DEFAULT, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS),
212 kmem_object);
213
214 obj_zone = &obj_zone_store;
215 zbootinit(obj_zone, "VM OBJECT", sizeof (struct vm_object),
216 vm_objects_init, VM_OBJECTS_INIT);
217}
218
219void
220vm_object_init2() {
221 zinitna(obj_zone, NULL, NULL, 0, 0, 0, 1);
222}
223
224/*
225 * vm_object_allocate:
226 *
227 * Returns a new object with the given size.
228 */
229
230vm_object_t
231vm_object_allocate(type, size)
232 objtype_t type;
233 vm_size_t size;
234{
235 vm_object_t result;
236
237 result = (vm_object_t) zalloc(obj_zone);
238
239 _vm_object_allocate(type, size, result);
240
241 return (result);
242}
243
244
245/*
246 * vm_object_reference:
247 *
248 * Gets another reference to the given object.
249 */
250void
251vm_object_reference(object)
252 vm_object_t object;
253{
254 if (object == NULL)
255 return;
256
257#if 0
258 /* object can be re-referenced during final cleaning */
259 KASSERT(!(object->flags & OBJ_DEAD),
260 ("vm_object_reference: attempting to reference dead obj"));
261#endif
262
263 object->ref_count++;
264 if (object->type == OBJT_VNODE) {
dadab5e9 265 while (vget((struct vnode *) object->handle, LK_RETRY|LK_NOOBJ, curthread)) {
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266 printf("vm_object_reference: delay in getting object\n");
267 }
268 }
269}
270
271void
272vm_object_vndeallocate(object)
273 vm_object_t object;
274{
275 struct vnode *vp = (struct vnode *) object->handle;
276
277 KASSERT(object->type == OBJT_VNODE,
278 ("vm_object_vndeallocate: not a vnode object"));
279 KASSERT(vp != NULL, ("vm_object_vndeallocate: missing vp"));
280#ifdef INVARIANTS
281 if (object->ref_count == 0) {
282 vprint("vm_object_vndeallocate", vp);
283 panic("vm_object_vndeallocate: bad object reference count");
284 }
285#endif
286
287 object->ref_count--;
288 if (object->ref_count == 0) {
289 vp->v_flag &= ~VTEXT;
290 vm_object_clear_flag(object, OBJ_OPT);
291 }
292 vrele(vp);
293}
294
295/*
296 * vm_object_deallocate:
297 *
298 * Release a reference to the specified object,
299 * gained either through a vm_object_allocate
300 * or a vm_object_reference call. When all references
301 * are gone, storage associated with this object
302 * may be relinquished.
303 *
304 * No object may be locked.
305 */
306void
307vm_object_deallocate(object)
308 vm_object_t object;
309{
310 vm_object_t temp;
311
312 while (object != NULL) {
313
314 if (object->type == OBJT_VNODE) {
315 vm_object_vndeallocate(object);
316 return;
317 }
318
319 if (object->ref_count == 0) {
320 panic("vm_object_deallocate: object deallocated too many times: %d", object->type);
321 } else if (object->ref_count > 2) {
322 object->ref_count--;
323 return;
324 }
325
326 /*
327 * Here on ref_count of one or two, which are special cases for
328 * objects.
329 */
330 if ((object->ref_count == 2) && (object->shadow_count == 0)) {
331 vm_object_set_flag(object, OBJ_ONEMAPPING);
332 object->ref_count--;
333 return;
334 } else if ((object->ref_count == 2) && (object->shadow_count == 1)) {
335 object->ref_count--;
336 if ((object->handle == NULL) &&
337 (object->type == OBJT_DEFAULT ||
338 object->type == OBJT_SWAP)) {
339 vm_object_t robject;
340
341 robject = LIST_FIRST(&object->shadow_head);
342 KASSERT(robject != NULL,
343 ("vm_object_deallocate: ref_count: %d, shadow_count: %d",
344 object->ref_count,
345 object->shadow_count));
346 if ((robject->handle == NULL) &&
347 (robject->type == OBJT_DEFAULT ||
348 robject->type == OBJT_SWAP)) {
349
350 robject->ref_count++;
351
352 while (
353 robject->paging_in_progress ||
354 object->paging_in_progress
355 ) {
356 vm_object_pip_sleep(robject, "objde1");
357 vm_object_pip_sleep(object, "objde2");
358 }
359
360 if (robject->ref_count == 1) {
361 robject->ref_count--;
362 object = robject;
363 goto doterm;
364 }
365
366 object = robject;
367 vm_object_collapse(object);
368 continue;
369 }
370 }
371
372 return;
373
374 } else {
375 object->ref_count--;
376 if (object->ref_count != 0)
377 return;
378 }
379
380doterm:
381
382 temp = object->backing_object;
383 if (temp) {
384 LIST_REMOVE(object, shadow_list);
385 temp->shadow_count--;
386 if (temp->ref_count == 0)
387 vm_object_clear_flag(temp, OBJ_OPT);
388 temp->generation++;
389 object->backing_object = NULL;
390 }
391
392 /*
393 * Don't double-terminate, we could be in a termination
394 * recursion due to the terminate having to sync data
395 * to disk.
396 */
397 if ((object->flags & OBJ_DEAD) == 0)
398 vm_object_terminate(object);
399 object = temp;
400 }
401}
402
403/*
404 * vm_object_terminate actually destroys the specified object, freeing
405 * up all previously used resources.
406 *
407 * The object must be locked.
408 * This routine may block.
409 */
410void
411vm_object_terminate(object)
412 vm_object_t object;
413{
414 vm_page_t p;
415 int s;
416
417 /*
418 * Make sure no one uses us.
419 */
420 vm_object_set_flag(object, OBJ_DEAD);
421
422 /*
423 * wait for the pageout daemon to be done with the object
424 */
425 vm_object_pip_wait(object, "objtrm");
426
427 KASSERT(!object->paging_in_progress,
428 ("vm_object_terminate: pageout in progress"));
429
430 /*
431 * Clean and free the pages, as appropriate. All references to the
432 * object are gone, so we don't need to lock it.
433 */
434 if (object->type == OBJT_VNODE) {
435 struct vnode *vp;
436
437 /*
438 * Freeze optimized copies.
439 */
440 vm_freeze_copyopts(object, 0, object->size);
441
442 /*
443 * Clean pages and flush buffers.
444 */
445 vm_object_page_clean(object, 0, 0, OBJPC_SYNC);
446
447 vp = (struct vnode *) object->handle;
3b568787 448 vinvalbuf(vp, V_SAVE, NULL, 0, 0);
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449 }
450
451 /*
452 * Wait for any I/O to complete, after which there had better not
453 * be any references left on the object.
454 */
455 vm_object_pip_wait(object, "objtrm");
456
457 if (object->ref_count != 0)
458 panic("vm_object_terminate: object with references, ref_count=%d", object->ref_count);
459
460 /*
461 * Now free any remaining pages. For internal objects, this also
462 * removes them from paging queues. Don't free wired pages, just
463 * remove them from the object.
464 */
465 s = splvm();
466 while ((p = TAILQ_FIRST(&object->memq)) != NULL) {
467 if (p->busy || (p->flags & PG_BUSY))
468 panic("vm_object_terminate: freeing busy page %p\n", p);
469 if (p->wire_count == 0) {
470 vm_page_busy(p);
471 vm_page_free(p);
12e4aaff 472 mycpu->gd_cnt.v_pfree++;
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473 } else {
474 vm_page_busy(p);
475 vm_page_remove(p);
476 }
477 }
478 splx(s);
479
480 /*
481 * Let the pager know object is dead.
482 */
483 vm_pager_deallocate(object);
484
485 /*
486 * Remove the object from the global object list.
487 */
8a8d5d85 488 lwkt_gettoken(&vm_object_list_token);
984263bc 489 TAILQ_REMOVE(&vm_object_list, object, object_list);
8a8d5d85 490 lwkt_reltoken(&vm_object_list_token);
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491
492 wakeup(object);
493
494 /*
495 * Free the space for the object.
496 */
497 zfree(obj_zone, object);
498}
499
500/*
501 * vm_object_page_clean
502 *
503 * Clean all dirty pages in the specified range of object. Leaves page
504 * on whatever queue it is currently on. If NOSYNC is set then do not
505 * write out pages with PG_NOSYNC set (originally comes from MAP_NOSYNC),
506 * leaving the object dirty.
507 *
508 * When stuffing pages asynchronously, allow clustering. XXX we need a
509 * synchronous clustering mode implementation.
510 *
511 * Odd semantics: if start == end, we clean everything.
512 *
513 * The object must be locked.
514 */
515
516void
517vm_object_page_clean(object, start, end, flags)
518 vm_object_t object;
519 vm_pindex_t start;
520 vm_pindex_t end;
521 int flags;
522{
523 vm_page_t p, np;
524 vm_offset_t tstart, tend;
525 vm_pindex_t pi;
526 struct vnode *vp;
527 int clearobjflags;
528 int pagerflags;
529 int curgeneration;
530
531 if (object->type != OBJT_VNODE ||
532 (object->flags & OBJ_MIGHTBEDIRTY) == 0)
533 return;
534
535 pagerflags = (flags & (OBJPC_SYNC | OBJPC_INVAL)) ? VM_PAGER_PUT_SYNC : VM_PAGER_CLUSTER_OK;
536 pagerflags |= (flags & OBJPC_INVAL) ? VM_PAGER_PUT_INVAL : 0;
537
538 vp = object->handle;
539
540 vm_object_set_flag(object, OBJ_CLEANING);
541
542 /*
543 * Handle 'entire object' case
544 */
545 tstart = start;
546 if (end == 0) {
547 tend = object->size;
548 } else {
549 tend = end;
550 }
551
552 /*
553 * If the caller is smart and only msync()s a range he knows is
554 * dirty, we may be able to avoid an object scan. This results in
555 * a phenominal improvement in performance. We cannot do this
556 * as a matter of course because the object may be huge - e.g.
557 * the size might be in the gigabytes or terrabytes.
558 */
559 if (msync_flush_flags & MSYNC_FLUSH_HARDSEQ) {
560 vm_offset_t tscan;
561 int scanlimit;
562 int scanreset;
563
564 scanreset = object->resident_page_count / EASY_SCAN_FACTOR;
565 if (scanreset < 16)
566 scanreset = 16;
567 pagerflags |= VM_PAGER_IGNORE_CLEANCHK;
568
569 scanlimit = scanreset;
570 tscan = tstart;
571 while (tscan < tend) {
572 curgeneration = object->generation;
573 p = vm_page_lookup(object, tscan);
574 if (p == NULL || p->valid == 0 ||
575 (p->queue - p->pc) == PQ_CACHE) {
576 if (--scanlimit == 0)
577 break;
578 ++tscan;
579 continue;
580 }
581 vm_page_test_dirty(p);
582 if ((p->dirty & p->valid) == 0) {
583 if (--scanlimit == 0)
584 break;
585 ++tscan;
586 continue;
587 }
588 /*
589 * If we have been asked to skip nosync pages and
590 * this is a nosync page, we can't continue.
591 */
592 if ((flags & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) {
593 if (--scanlimit == 0)
594 break;
595 ++tscan;
596 continue;
597 }
598 scanlimit = scanreset;
599
600 /*
601 * This returns 0 if it was unable to busy the first
602 * page (i.e. had to sleep).
603 */
604 tscan += vm_object_page_collect_flush(object, p, curgeneration, pagerflags);
605 }
606
607 /*
608 * If everything was dirty and we flushed it successfully,
609 * and the requested range is not the entire object, we
610 * don't have to mess with CLEANCHK or MIGHTBEDIRTY and can
611 * return immediately.
612 */
613 if (tscan >= tend && (tstart || tend < object->size)) {
614 vm_object_clear_flag(object, OBJ_CLEANING);
615 return;
616 }
617 pagerflags &= ~VM_PAGER_IGNORE_CLEANCHK;
618 }
619
620 /*
621 * Generally set CLEANCHK interlock and make the page read-only so
622 * we can then clear the object flags.
623 *
624 * However, if this is a nosync mmap then the object is likely to
625 * stay dirty so do not mess with the page and do not clear the
626 * object flags.
627 */
628
629 clearobjflags = 1;
630
631 for(p = TAILQ_FIRST(&object->memq); p; p = TAILQ_NEXT(p, listq)) {
632 vm_page_flag_set(p, PG_CLEANCHK);
633 if ((flags & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC))
634 clearobjflags = 0;
635 else
636 vm_page_protect(p, VM_PROT_READ);
637 }
638
639 if (clearobjflags && (tstart == 0) && (tend == object->size)) {
640 struct vnode *vp;
641
642 vm_object_clear_flag(object, OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY);
643 if (object->type == OBJT_VNODE &&
644 (vp = (struct vnode *)object->handle) != NULL) {
645 if (vp->v_flag & VOBJDIRTY) {
8a8d5d85 646 lwkt_gettoken(&vp->v_interlock);
984263bc 647 vp->v_flag &= ~VOBJDIRTY;
8a8d5d85 648 lwkt_reltoken(&vp->v_interlock);
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649 }
650 }
651 }
652
653rescan:
654 curgeneration = object->generation;
655
656 for(p = TAILQ_FIRST(&object->memq); p; p = np) {
657 int n;
658
659 np = TAILQ_NEXT(p, listq);
660
661again:
662 pi = p->pindex;
663 if (((p->flags & PG_CLEANCHK) == 0) ||
664 (pi < tstart) || (pi >= tend) ||
665 (p->valid == 0) ||
666 ((p->queue - p->pc) == PQ_CACHE)) {
667 vm_page_flag_clear(p, PG_CLEANCHK);
668 continue;
669 }
670
671 vm_page_test_dirty(p);
672 if ((p->dirty & p->valid) == 0) {
673 vm_page_flag_clear(p, PG_CLEANCHK);
674 continue;
675 }
676
677 /*
678 * If we have been asked to skip nosync pages and this is a
679 * nosync page, skip it. Note that the object flags were
680 * not cleared in this case so we do not have to set them.
681 */
682 if ((flags & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) {
683 vm_page_flag_clear(p, PG_CLEANCHK);
684 continue;
685 }
686
687 n = vm_object_page_collect_flush(object, p,
688 curgeneration, pagerflags);
689 if (n == 0)
690 goto rescan;
691 if (object->generation != curgeneration)
692 goto rescan;
693
694 /*
695 * Try to optimize the next page. If we can't we pick up
696 * our (random) scan where we left off.
697 */
698 if (msync_flush_flags & MSYNC_FLUSH_SOFTSEQ) {
699 if ((p = vm_page_lookup(object, pi + n)) != NULL)
700 goto again;
701 }
702 }
703
704#if 0
705 VOP_FSYNC(vp, NULL, (pagerflags & VM_PAGER_PUT_SYNC)?MNT_WAIT:0, curproc);
706#endif
707
708 vm_object_clear_flag(object, OBJ_CLEANING);
709 return;
710}
711
712static int
713vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int curgeneration, int pagerflags)
714{
715 int runlen;
716 int s;
717 int maxf;
718 int chkb;
719 int maxb;
720 int i;
721 vm_pindex_t pi;
722 vm_page_t maf[vm_pageout_page_count];
723 vm_page_t mab[vm_pageout_page_count];
724 vm_page_t ma[vm_pageout_page_count];
725
726 s = splvm();
727 pi = p->pindex;
728 while (vm_page_sleep_busy(p, TRUE, "vpcwai")) {
729 if (object->generation != curgeneration) {
730 splx(s);
731 return(0);
732 }
733 }
734
735 maxf = 0;
736 for(i = 1; i < vm_pageout_page_count; i++) {
737 vm_page_t tp;
738
739 if ((tp = vm_page_lookup(object, pi + i)) != NULL) {
740 if ((tp->flags & PG_BUSY) ||
741 ((pagerflags & VM_PAGER_IGNORE_CLEANCHK) == 0 &&
742 (tp->flags & PG_CLEANCHK) == 0) ||
743 (tp->busy != 0))
744 break;
745 if((tp->queue - tp->pc) == PQ_CACHE) {
746 vm_page_flag_clear(tp, PG_CLEANCHK);
747 break;
748 }
749 vm_page_test_dirty(tp);
750 if ((tp->dirty & tp->valid) == 0) {
751 vm_page_flag_clear(tp, PG_CLEANCHK);
752 break;
753 }
754 maf[ i - 1 ] = tp;
755 maxf++;
756 continue;
757 }
758 break;
759 }
760
761 maxb = 0;
762 chkb = vm_pageout_page_count - maxf;
763 if (chkb) {
764 for(i = 1; i < chkb;i++) {
765 vm_page_t tp;
766
767 if ((tp = vm_page_lookup(object, pi - i)) != NULL) {
768 if ((tp->flags & PG_BUSY) ||
769 ((pagerflags & VM_PAGER_IGNORE_CLEANCHK) == 0 &&
770 (tp->flags & PG_CLEANCHK) == 0) ||
771 (tp->busy != 0))
772 break;
773 if((tp->queue - tp->pc) == PQ_CACHE) {
774 vm_page_flag_clear(tp, PG_CLEANCHK);
775 break;
776 }
777 vm_page_test_dirty(tp);
778 if ((tp->dirty & tp->valid) == 0) {
779 vm_page_flag_clear(tp, PG_CLEANCHK);
780 break;
781 }
782 mab[ i - 1 ] = tp;
783 maxb++;
784 continue;
785 }
786 break;
787 }
788 }
789
790 for(i = 0; i < maxb; i++) {
791 int index = (maxb - i) - 1;
792 ma[index] = mab[i];
793 vm_page_flag_clear(ma[index], PG_CLEANCHK);
794 }
795 vm_page_flag_clear(p, PG_CLEANCHK);
796 ma[maxb] = p;
797 for(i = 0; i < maxf; i++) {
798 int index = (maxb + i) + 1;
799 ma[index] = maf[i];
800 vm_page_flag_clear(ma[index], PG_CLEANCHK);
801 }
802 runlen = maxb + maxf + 1;
803
804 splx(s);
805 vm_pageout_flush(ma, runlen, pagerflags);
806 for (i = 0; i < runlen; i++) {
807 if (ma[i]->valid & ma[i]->dirty) {
808 vm_page_protect(ma[i], VM_PROT_READ);
809 vm_page_flag_set(ma[i], PG_CLEANCHK);
810
811 /*
812 * maxf will end up being the actual number of pages
813 * we wrote out contiguously, non-inclusive of the
814 * first page. We do not count look-behind pages.
815 */
816 if (i >= maxb + 1 && (maxf > i - maxb - 1))
817 maxf = i - maxb - 1;
818 }
819 }
820 return(maxf + 1);
821}
822
823#ifdef not_used
824/* XXX I cannot tell if this should be an exported symbol */
825/*
826 * vm_object_deactivate_pages
827 *
828 * Deactivate all pages in the specified object. (Keep its pages
829 * in memory even though it is no longer referenced.)
830 *
831 * The object must be locked.
832 */
833static void
834vm_object_deactivate_pages(object)
835 vm_object_t object;
836{
837 vm_page_t p, next;
838
839 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = next) {
840 next = TAILQ_NEXT(p, listq);
841 vm_page_deactivate(p);
842 }
843}
844#endif
845
846/*
847 * Same as vm_object_pmap_copy, except range checking really
848 * works, and is meant for small sections of an object.
849 *
850 * This code protects resident pages by making them read-only
851 * and is typically called on a fork or split when a page
852 * is converted to copy-on-write.
853 *
854 * NOTE: If the page is already at VM_PROT_NONE, calling
855 * vm_page_protect will have no effect.
856 */
857
858void
859vm_object_pmap_copy_1(object, start, end)
860 vm_object_t object;
861 vm_pindex_t start;
862 vm_pindex_t end;
863{
864 vm_pindex_t idx;
865 vm_page_t p;
866
867 if (object == NULL || (object->flags & OBJ_WRITEABLE) == 0)
868 return;
869
870 for (idx = start; idx < end; idx++) {
871 p = vm_page_lookup(object, idx);
872 if (p == NULL)
873 continue;
874 vm_page_protect(p, VM_PROT_READ);
875 }
876}
877
878/*
879 * vm_object_pmap_remove:
880 *
881 * Removes all physical pages in the specified
882 * object range from all physical maps.
883 *
884 * The object must *not* be locked.
885 */
886void
887vm_object_pmap_remove(object, start, end)
888 vm_object_t object;
889 vm_pindex_t start;
890 vm_pindex_t end;
891{
892 vm_page_t p;
893
894 if (object == NULL)
895 return;
896 for (p = TAILQ_FIRST(&object->memq);
897 p != NULL;
898 p = TAILQ_NEXT(p, listq)) {
899 if (p->pindex >= start && p->pindex < end)
900 vm_page_protect(p, VM_PROT_NONE);
901 }
902 if ((start == 0) && (object->size == end))
903 vm_object_clear_flag(object, OBJ_WRITEABLE);
904}
905
906/*
907 * vm_object_madvise:
908 *
909 * Implements the madvise function at the object/page level.
910 *
911 * MADV_WILLNEED (any object)
912 *
913 * Activate the specified pages if they are resident.
914 *
915 * MADV_DONTNEED (any object)
916 *
917 * Deactivate the specified pages if they are resident.
918 *
919 * MADV_FREE (OBJT_DEFAULT/OBJT_SWAP objects,
920 * OBJ_ONEMAPPING only)
921 *
922 * Deactivate and clean the specified pages if they are
923 * resident. This permits the process to reuse the pages
924 * without faulting or the kernel to reclaim the pages
925 * without I/O.
926 */
927void
928vm_object_madvise(object, pindex, count, advise)
929 vm_object_t object;
930 vm_pindex_t pindex;
931 int count;
932 int advise;
933{
934 vm_pindex_t end, tpindex;
935 vm_object_t tobject;
936 vm_page_t m;
937
938 if (object == NULL)
939 return;
940
941 end = pindex + count;
942
943 /*
944 * Locate and adjust resident pages
945 */
946
947 for (; pindex < end; pindex += 1) {
948relookup:
949 tobject = object;
950 tpindex = pindex;
951shadowlookup:
952 /*
953 * MADV_FREE only operates on OBJT_DEFAULT or OBJT_SWAP pages
954 * and those pages must be OBJ_ONEMAPPING.
955 */
956 if (advise == MADV_FREE) {
957 if ((tobject->type != OBJT_DEFAULT &&
958 tobject->type != OBJT_SWAP) ||
959 (tobject->flags & OBJ_ONEMAPPING) == 0) {
960 continue;
961 }
962 }
963
964 m = vm_page_lookup(tobject, tpindex);
965
966 if (m == NULL) {
967 /*
968 * There may be swap even if there is no backing page
969 */
970 if (advise == MADV_FREE && tobject->type == OBJT_SWAP)
971 swap_pager_freespace(tobject, tpindex, 1);
972
973 /*
974 * next object
975 */
976 tobject = tobject->backing_object;
977 if (tobject == NULL)
978 continue;
979 tpindex += OFF_TO_IDX(tobject->backing_object_offset);
980 goto shadowlookup;
981 }
982
983 /*
984 * If the page is busy or not in a normal active state,
985 * we skip it. If the page is not managed there are no
986 * page queues to mess with. Things can break if we mess
987 * with pages in any of the below states.
988 */
989 if (
990 m->hold_count ||
991 m->wire_count ||
992 (m->flags & PG_UNMANAGED) ||
993 m->valid != VM_PAGE_BITS_ALL
994 ) {
995 continue;
996 }
997
998 if (vm_page_sleep_busy(m, TRUE, "madvpo"))
999 goto relookup;
1000
1001 if (advise == MADV_WILLNEED) {
1002 vm_page_activate(m);
1003 } else if (advise == MADV_DONTNEED) {
1004 vm_page_dontneed(m);
1005 } else if (advise == MADV_FREE) {
1006 /*
1007 * Mark the page clean. This will allow the page
1008 * to be freed up by the system. However, such pages
1009 * are often reused quickly by malloc()/free()
1010 * so we do not do anything that would cause
1011 * a page fault if we can help it.
1012 *
1013 * Specifically, we do not try to actually free
1014 * the page now nor do we try to put it in the
1015 * cache (which would cause a page fault on reuse).
1016 *
1017 * But we do make the page is freeable as we
1018 * can without actually taking the step of unmapping
1019 * it.
1020 */
1021 pmap_clear_modify(m);
1022 m->dirty = 0;
1023 m->act_count = 0;
1024 vm_page_dontneed(m);
1025 if (tobject->type == OBJT_SWAP)
1026 swap_pager_freespace(tobject, tpindex, 1);
1027 }
1028 }
1029}
1030
1031/*
1032 * vm_object_shadow:
1033 *
1034 * Create a new object which is backed by the
1035 * specified existing object range. The source
1036 * object reference is deallocated.
1037 *
1038 * The new object and offset into that object
1039 * are returned in the source parameters.
1040 */
1041
1042void
1043vm_object_shadow(object, offset, length)
1044 vm_object_t *object; /* IN/OUT */
1045 vm_ooffset_t *offset; /* IN/OUT */
1046 vm_size_t length;
1047{
1048 vm_object_t source;
1049 vm_object_t result;
1050
1051 source = *object;
1052
1053 /*
1054 * Don't create the new object if the old object isn't shared.
1055 */
1056
1057 if (source != NULL &&
1058 source->ref_count == 1 &&
1059 source->handle == NULL &&
1060 (source->type == OBJT_DEFAULT ||
1061 source->type == OBJT_SWAP))
1062 return;
1063
1064 /*
1065 * Allocate a new object with the given length
1066 */
1067
1068 if ((result = vm_object_allocate(OBJT_DEFAULT, length)) == NULL)
1069 panic("vm_object_shadow: no object for shadowing");
1070
1071 /*
1072 * The new object shadows the source object, adding a reference to it.
1073 * Our caller changes his reference to point to the new object,
1074 * removing a reference to the source object. Net result: no change
1075 * of reference count.
1076 *
1077 * Try to optimize the result object's page color when shadowing
1078 * in order to maintain page coloring consistency in the combined
1079 * shadowed object.
1080 */
1081 result->backing_object = source;
1082 if (source) {
1083 LIST_INSERT_HEAD(&source->shadow_head, result, shadow_list);
1084 source->shadow_count++;
1085 source->generation++;
1086 result->pg_color = (source->pg_color + OFF_TO_IDX(*offset)) & PQ_L2_MASK;
1087 }
1088
1089 /*
1090 * Store the offset into the source object, and fix up the offset into
1091 * the new object.
1092 */
1093
1094 result->backing_object_offset = *offset;
1095
1096 /*
1097 * Return the new things
1098 */
1099
1100 *offset = 0;
1101 *object = result;
1102}
1103
1104#define OBSC_TEST_ALL_SHADOWED 0x0001
1105#define OBSC_COLLAPSE_NOWAIT 0x0002
1106#define OBSC_COLLAPSE_WAIT 0x0004
1107
1108static __inline int
1109vm_object_backing_scan(vm_object_t object, int op)
1110{
1111 int s;
1112 int r = 1;
1113 vm_page_t p;
1114 vm_object_t backing_object;
1115 vm_pindex_t backing_offset_index;
1116
1117 s = splvm();
1118
1119 backing_object = object->backing_object;
1120 backing_offset_index = OFF_TO_IDX(object->backing_object_offset);
1121
1122 /*
1123 * Initial conditions
1124 */
1125
1126 if (op & OBSC_TEST_ALL_SHADOWED) {
1127 /*
1128 * We do not want to have to test for the existence of
1129 * swap pages in the backing object. XXX but with the
1130 * new swapper this would be pretty easy to do.
1131 *
1132 * XXX what about anonymous MAP_SHARED memory that hasn't
1133 * been ZFOD faulted yet? If we do not test for this, the
1134 * shadow test may succeed! XXX
1135 */
1136 if (backing_object->type != OBJT_DEFAULT) {
1137 splx(s);
1138 return(0);
1139 }
1140 }
1141 if (op & OBSC_COLLAPSE_WAIT) {
1142 vm_object_set_flag(backing_object, OBJ_DEAD);
1143 }
1144
1145 /*
1146 * Our scan
1147 */
1148
1149 p = TAILQ_FIRST(&backing_object->memq);
1150 while (p) {
1151 vm_page_t next = TAILQ_NEXT(p, listq);
1152 vm_pindex_t new_pindex = p->pindex - backing_offset_index;
1153
1154 if (op & OBSC_TEST_ALL_SHADOWED) {
1155 vm_page_t pp;
1156
1157 /*
1158 * Ignore pages outside the parent object's range
1159 * and outside the parent object's mapping of the
1160 * backing object.
1161 *
1162 * note that we do not busy the backing object's
1163 * page.
1164 */
1165
1166 if (
1167 p->pindex < backing_offset_index ||
1168 new_pindex >= object->size
1169 ) {
1170 p = next;
1171 continue;
1172 }
1173
1174 /*
1175 * See if the parent has the page or if the parent's
1176 * object pager has the page. If the parent has the
1177 * page but the page is not valid, the parent's
1178 * object pager must have the page.
1179 *
1180 * If this fails, the parent does not completely shadow
1181 * the object and we might as well give up now.
1182 */
1183
1184 pp = vm_page_lookup(object, new_pindex);
1185 if (
1186 (pp == NULL || pp->valid == 0) &&
1187 !vm_pager_has_page(object, new_pindex, NULL, NULL)
1188 ) {
1189 r = 0;
1190 break;
1191 }
1192 }
1193
1194 /*
1195 * Check for busy page
1196 */
1197
1198 if (op & (OBSC_COLLAPSE_WAIT | OBSC_COLLAPSE_NOWAIT)) {
1199 vm_page_t pp;
1200
1201 if (op & OBSC_COLLAPSE_NOWAIT) {
1202 if (
1203 (p->flags & PG_BUSY) ||
1204 !p->valid ||
1205 p->hold_count ||
1206 p->wire_count ||
1207 p->busy
1208 ) {
1209 p = next;
1210 continue;
1211 }
1212 } else if (op & OBSC_COLLAPSE_WAIT) {
1213 if (vm_page_sleep_busy(p, TRUE, "vmocol")) {
1214 /*
1215 * If we slept, anything could have
1216 * happened. Since the object is
1217 * marked dead, the backing offset
1218 * should not have changed so we
1219 * just restart our scan.
1220 */
1221 p = TAILQ_FIRST(&backing_object->memq);
1222 continue;
1223 }
1224 }
1225
1226 /*
1227 * Busy the page
1228 */
1229 vm_page_busy(p);
1230
1231 KASSERT(
1232 p->object == backing_object,
1233 ("vm_object_qcollapse(): object mismatch")
1234 );
1235
1236 /*
1237 * Destroy any associated swap
1238 */
1239 if (backing_object->type == OBJT_SWAP) {
1240 swap_pager_freespace(
1241 backing_object,
1242 p->pindex,
1243 1
1244 );
1245 }
1246
1247 if (
1248 p->pindex < backing_offset_index ||
1249 new_pindex >= object->size
1250 ) {
1251 /*
1252 * Page is out of the parent object's range, we
1253 * can simply destroy it.
1254 */
1255 vm_page_protect(p, VM_PROT_NONE);
1256 vm_page_free(p);
1257 p = next;
1258 continue;
1259 }
1260
1261 pp = vm_page_lookup(object, new_pindex);
1262 if (
1263 pp != NULL ||
1264 vm_pager_has_page(object, new_pindex, NULL, NULL)
1265 ) {
1266 /*
1267 * page already exists in parent OR swap exists
1268 * for this location in the parent. Destroy
1269 * the original page from the backing object.
1270 *
1271 * Leave the parent's page alone
1272 */
1273 vm_page_protect(p, VM_PROT_NONE);
1274 vm_page_free(p);
1275 p = next;
1276 continue;
1277 }
1278
1279 /*
1280 * Page does not exist in parent, rename the
1281 * page from the backing object to the main object.
1282 *
1283 * If the page was mapped to a process, it can remain
1284 * mapped through the rename.
1285 */
1286 if ((p->queue - p->pc) == PQ_CACHE)
1287 vm_page_deactivate(p);
1288
1289 vm_page_rename(p, object, new_pindex);
1290 /* page automatically made dirty by rename */
1291 }
1292 p = next;
1293 }
1294 splx(s);
1295 return(r);
1296}
1297
1298
1299/*
1300 * this version of collapse allows the operation to occur earlier and
1301 * when paging_in_progress is true for an object... This is not a complete
1302 * operation, but should plug 99.9% of the rest of the leaks.
1303 */
1304static void
1305vm_object_qcollapse(object)
1306 vm_object_t object;
1307{
1308 vm_object_t backing_object = object->backing_object;
1309
1310 if (backing_object->ref_count != 1)
1311 return;
1312
1313 backing_object->ref_count += 2;
1314
1315 vm_object_backing_scan(object, OBSC_COLLAPSE_NOWAIT);
1316
1317 backing_object->ref_count -= 2;
1318}
1319
1320/*
1321 * vm_object_collapse:
1322 *
1323 * Collapse an object with the object backing it.
1324 * Pages in the backing object are moved into the
1325 * parent, and the backing object is deallocated.
1326 */
1327void
1328vm_object_collapse(object)
1329 vm_object_t object;
1330{
1331 while (TRUE) {
1332 vm_object_t backing_object;
1333
1334 /*
1335 * Verify that the conditions are right for collapse:
1336 *
1337 * The object exists and the backing object exists.
1338 */
1339 if (object == NULL)
1340 break;
1341
1342 if ((backing_object = object->backing_object) == NULL)
1343 break;
1344
1345 /*
1346 * we check the backing object first, because it is most likely
1347 * not collapsable.
1348 */
1349 if (backing_object->handle != NULL ||
1350 (backing_object->type != OBJT_DEFAULT &&
1351 backing_object->type != OBJT_SWAP) ||
1352 (backing_object->flags & OBJ_DEAD) ||
1353 object->handle != NULL ||
1354 (object->type != OBJT_DEFAULT &&
1355 object->type != OBJT_SWAP) ||
1356 (object->flags & OBJ_DEAD)) {
1357 break;
1358 }
1359
1360 if (
1361 object->paging_in_progress != 0 ||
1362 backing_object->paging_in_progress != 0
1363 ) {
1364 vm_object_qcollapse(object);
1365 break;
1366 }
1367
1368 /*
1369 * We know that we can either collapse the backing object (if
1370 * the parent is the only reference to it) or (perhaps) have
1371 * the parent bypass the object if the parent happens to shadow
1372 * all the resident pages in the entire backing object.
1373 *
1374 * This is ignoring pager-backed pages such as swap pages.
1375 * vm_object_backing_scan fails the shadowing test in this
1376 * case.
1377 */
1378
1379 if (backing_object->ref_count == 1) {
1380 /*
1381 * If there is exactly one reference to the backing
1382 * object, we can collapse it into the parent.
1383 */
1384
1385 vm_object_backing_scan(object, OBSC_COLLAPSE_WAIT);
1386
1387 /*
1388 * Move the pager from backing_object to object.
1389 */
1390
1391 if (backing_object->type == OBJT_SWAP) {
1392 vm_object_pip_add(backing_object, 1);
1393
1394 /*
1395 * scrap the paging_offset junk and do a
1396 * discrete copy. This also removes major
1397 * assumptions about how the swap-pager
1398 * works from where it doesn't belong. The
1399 * new swapper is able to optimize the
1400 * destroy-source case.
1401 */
1402
1403 vm_object_pip_add(object, 1);
1404 swap_pager_copy(
1405 backing_object,
1406 object,
1407 OFF_TO_IDX(object->backing_object_offset), TRUE);
1408 vm_object_pip_wakeup(object);
1409
1410 vm_object_pip_wakeup(backing_object);
1411 }
1412 /*
1413 * Object now shadows whatever backing_object did.
1414 * Note that the reference to
1415 * backing_object->backing_object moves from within
1416 * backing_object to within object.
1417 */
1418
1419 LIST_REMOVE(object, shadow_list);
1420 object->backing_object->shadow_count--;
1421 object->backing_object->generation++;
1422 if (backing_object->backing_object) {
1423 LIST_REMOVE(backing_object, shadow_list);
1424 backing_object->backing_object->shadow_count--;
1425 backing_object->backing_object->generation++;
1426 }
1427 object->backing_object = backing_object->backing_object;
1428 if (object->backing_object) {
1429 LIST_INSERT_HEAD(
1430 &object->backing_object->shadow_head,
1431 object,
1432 shadow_list
1433 );
1434 object->backing_object->shadow_count++;
1435 object->backing_object->generation++;
1436 }
1437
1438 object->backing_object_offset +=
1439 backing_object->backing_object_offset;
1440
1441 /*
1442 * Discard backing_object.
1443 *
1444 * Since the backing object has no pages, no pager left,
1445 * and no object references within it, all that is
1446 * necessary is to dispose of it.
1447 */
1448
1449 KASSERT(backing_object->ref_count == 1, ("backing_object %p was somehow re-referenced during collapse!", backing_object));
1450 KASSERT(TAILQ_FIRST(&backing_object->memq) == NULL, ("backing_object %p somehow has left over pages during collapse!", backing_object));
1451 TAILQ_REMOVE(
1452 &vm_object_list,
1453 backing_object,
1454 object_list
1455 );
1456 vm_object_count--;
1457
1458 zfree(obj_zone, backing_object);
1459
1460 object_collapses++;
1461 } else {
1462 vm_object_t new_backing_object;
1463
1464 /*
1465 * If we do not entirely shadow the backing object,
1466 * there is nothing we can do so we give up.
1467 */
1468
1469 if (vm_object_backing_scan(object, OBSC_TEST_ALL_SHADOWED) == 0) {
1470 break;
1471 }
1472
1473 /*
1474 * Make the parent shadow the next object in the
1475 * chain. Deallocating backing_object will not remove
1476 * it, since its reference count is at least 2.
1477 */
1478
1479 LIST_REMOVE(object, shadow_list);
1480 backing_object->shadow_count--;
1481 backing_object->generation++;
1482
1483 new_backing_object = backing_object->backing_object;
1484 if ((object->backing_object = new_backing_object) != NULL) {
1485 vm_object_reference(new_backing_object);
1486 LIST_INSERT_HEAD(
1487 &new_backing_object->shadow_head,
1488 object,
1489 shadow_list
1490 );
1491 new_backing_object->shadow_count++;
1492 new_backing_object->generation++;
1493 object->backing_object_offset +=
1494 backing_object->backing_object_offset;
1495 }
1496
1497 /*
1498 * Drop the reference count on backing_object. Since
1499 * its ref_count was at least 2, it will not vanish;
1500 * so we don't need to call vm_object_deallocate, but
1501 * we do anyway.
1502 */
1503 vm_object_deallocate(backing_object);
1504 object_bypasses++;
1505 }
1506
1507 /*
1508 * Try again with this object's new backing object.
1509 */
1510 }
1511}
1512
1513/*
1514 * vm_object_page_remove: [internal]
1515 *
1516 * Removes all physical pages in the specified
1517 * object range from the object's list of pages.
1518 *
1519 * The object must be locked.
1520 */
1521void
1522vm_object_page_remove(object, start, end, clean_only)
1523 vm_object_t object;
1524 vm_pindex_t start;
1525 vm_pindex_t end;
1526 boolean_t clean_only;
1527{
1528 vm_page_t p, next;
1529 unsigned int size;
1530 int all;
1531
1532 if (object == NULL ||
1533 object->resident_page_count == 0)
1534 return;
1535
1536 all = ((end == 0) && (start == 0));
1537
1538 /*
1539 * Since physically-backed objects do not use managed pages, we can't
1540 * remove pages from the object (we must instead remove the page
1541 * references, and then destroy the object).
1542 */
1543 KASSERT(object->type != OBJT_PHYS, ("attempt to remove pages from a physical object"));
1544
1545 vm_object_pip_add(object, 1);
1546again:
1547 size = end - start;
1548 if (all || size > object->resident_page_count / 4) {
1549 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = next) {
1550 next = TAILQ_NEXT(p, listq);
1551 if (all || ((start <= p->pindex) && (p->pindex < end))) {
1552 if (p->wire_count != 0) {
1553 vm_page_protect(p, VM_PROT_NONE);
1554 if (!clean_only)
1555 p->valid = 0;
1556 continue;
1557 }
1558
1559 /*
1560 * The busy flags are only cleared at
1561 * interrupt -- minimize the spl transitions
1562 */
1563
1564 if (vm_page_sleep_busy(p, TRUE, "vmopar"))
1565 goto again;
1566
1567 if (clean_only && p->valid) {
1568 vm_page_test_dirty(p);
1569 if (p->valid & p->dirty)
1570 continue;
1571 }
1572
1573 vm_page_busy(p);
1574 vm_page_protect(p, VM_PROT_NONE);
1575 vm_page_free(p);
1576 }
1577 }
1578 } else {
1579 while (size > 0) {
1580 if ((p = vm_page_lookup(object, start)) != 0) {
1581
1582 if (p->wire_count != 0) {
1583 vm_page_protect(p, VM_PROT_NONE);
1584 if (!clean_only)
1585 p->valid = 0;
1586 start += 1;
1587 size -= 1;
1588 continue;
1589 }
1590
1591 /*
1592 * The busy flags are only cleared at
1593 * interrupt -- minimize the spl transitions
1594 */
1595 if (vm_page_sleep_busy(p, TRUE, "vmopar"))
1596 goto again;
1597
1598 if (clean_only && p->valid) {
1599 vm_page_test_dirty(p);
1600 if (p->valid & p->dirty) {
1601 start += 1;
1602 size -= 1;
1603 continue;
1604 }
1605 }
1606
1607 vm_page_busy(p);
1608 vm_page_protect(p, VM_PROT_NONE);
1609 vm_page_free(p);
1610 }
1611 start += 1;
1612 size -= 1;
1613 }
1614 }
1615 vm_object_pip_wakeup(object);
1616}
1617
1618/*
1619 * Routine: vm_object_coalesce
1620 * Function: Coalesces two objects backing up adjoining
1621 * regions of memory into a single object.
1622 *
1623 * returns TRUE if objects were combined.
1624 *
1625 * NOTE: Only works at the moment if the second object is NULL -
1626 * if it's not, which object do we lock first?
1627 *
1628 * Parameters:
1629 * prev_object First object to coalesce
1630 * prev_offset Offset into prev_object
1631 * next_object Second object into coalesce
1632 * next_offset Offset into next_object
1633 *
1634 * prev_size Size of reference to prev_object
1635 * next_size Size of reference to next_object
1636 *
1637 * Conditions:
1638 * The object must *not* be locked.
1639 */
1640boolean_t
1641vm_object_coalesce(prev_object, prev_pindex, prev_size, next_size)
1642 vm_object_t prev_object;
1643 vm_pindex_t prev_pindex;
1644 vm_size_t prev_size, next_size;
1645{
1646 vm_pindex_t next_pindex;
1647
1648 if (prev_object == NULL) {
1649 return (TRUE);
1650 }
1651
1652 if (prev_object->type != OBJT_DEFAULT &&
1653 prev_object->type != OBJT_SWAP) {
1654 return (FALSE);
1655 }
1656
1657 /*
1658 * Try to collapse the object first
1659 */
1660 vm_object_collapse(prev_object);
1661
1662 /*
1663 * Can't coalesce if: . more than one reference . paged out . shadows
1664 * another object . has a copy elsewhere (any of which mean that the
1665 * pages not mapped to prev_entry may be in use anyway)
1666 */
1667
1668 if (prev_object->backing_object != NULL) {
1669 return (FALSE);
1670 }
1671
1672 prev_size >>= PAGE_SHIFT;
1673 next_size >>= PAGE_SHIFT;
1674 next_pindex = prev_pindex + prev_size;
1675
1676 if ((prev_object->ref_count > 1) &&
1677 (prev_object->size != next_pindex)) {
1678 return (FALSE);
1679 }
1680
1681 /*
1682 * Remove any pages that may still be in the object from a previous
1683 * deallocation.
1684 */
1685 if (next_pindex < prev_object->size) {
1686 vm_object_page_remove(prev_object,
1687 next_pindex,
1688 next_pindex + next_size, FALSE);
1689 if (prev_object->type == OBJT_SWAP)
1690 swap_pager_freespace(prev_object,
1691 next_pindex, next_size);
1692 }
1693
1694 /*
1695 * Extend the object if necessary.
1696 */
1697 if (next_pindex + next_size > prev_object->size)
1698 prev_object->size = next_pindex + next_size;
1699
1700 return (TRUE);
1701}
1702
1703void
1704vm_object_set_writeable_dirty(vm_object_t object)
1705{
1706 struct vnode *vp;
1707
1708 vm_object_set_flag(object, OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY);
1709 if (object->type == OBJT_VNODE &&
1710 (vp = (struct vnode *)object->handle) != NULL) {
1711 if ((vp->v_flag & VOBJDIRTY) == 0) {
8a8d5d85 1712 lwkt_gettoken(&vp->v_interlock);
984263bc 1713 vp->v_flag |= VOBJDIRTY;
8a8d5d85 1714 lwkt_reltoken(&vp->v_interlock);
984263bc
MD
1715 }
1716 }
1717}
1718
1719
1720
1721#include "opt_ddb.h"
1722#ifdef DDB
1723#include <sys/kernel.h>
1724
1725#include <sys/cons.h>
1726
1727#include <ddb/ddb.h>
1728
1729static int _vm_object_in_map __P((vm_map_t map, vm_object_t object,
1730 vm_map_entry_t entry));
1731static int vm_object_in_map __P((vm_object_t object));
1732
1733static int
1734_vm_object_in_map(map, object, entry)
1735 vm_map_t map;
1736 vm_object_t object;
1737 vm_map_entry_t entry;
1738{
1739 vm_map_t tmpm;
1740 vm_map_entry_t tmpe;
1741 vm_object_t obj;
1742 int entcount;
1743
1744 if (map == 0)
1745 return 0;
1746
1747 if (entry == 0) {
1748 tmpe = map->header.next;
1749 entcount = map->nentries;
1750 while (entcount-- && (tmpe != &map->header)) {
1751 if( _vm_object_in_map(map, object, tmpe)) {
1752 return 1;
1753 }
1754 tmpe = tmpe->next;
1755 }
1756 } else if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) {
1757 tmpm = entry->object.sub_map;
1758 tmpe = tmpm->header.next;
1759 entcount = tmpm->nentries;
1760 while (entcount-- && tmpe != &tmpm->header) {
1761 if( _vm_object_in_map(tmpm, object, tmpe)) {
1762 return 1;
1763 }
1764 tmpe = tmpe->next;
1765 }
1766 } else if ((obj = entry->object.vm_object) != NULL) {
1767 for(; obj; obj=obj->backing_object)
1768 if( obj == object) {
1769 return 1;
1770 }
1771 }
1772 return 0;
1773}
1774
1775static int
1776vm_object_in_map( object)
1777 vm_object_t object;
1778{
1779 struct proc *p;
1780 for (p = allproc.lh_first; p != 0; p = p->p_list.le_next) {
1781 if( !p->p_vmspace /* || (p->p_flag & (P_SYSTEM|P_WEXIT)) */)
1782 continue;
1783 if( _vm_object_in_map(&p->p_vmspace->vm_map, object, 0))
1784 return 1;
1785 }
1786 if( _vm_object_in_map( kernel_map, object, 0))
1787 return 1;
1788 if( _vm_object_in_map( kmem_map, object, 0))
1789 return 1;
1790 if( _vm_object_in_map( pager_map, object, 0))
1791 return 1;
1792 if( _vm_object_in_map( buffer_map, object, 0))
1793 return 1;
1794 if( _vm_object_in_map( mb_map, object, 0))
1795 return 1;
1796 return 0;
1797}
1798
1799DB_SHOW_COMMAND(vmochk, vm_object_check)
1800{
1801 vm_object_t object;
1802
1803 /*
1804 * make sure that internal objs are in a map somewhere
1805 * and none have zero ref counts.
1806 */
1807 for (object = TAILQ_FIRST(&vm_object_list);
1808 object != NULL;
1809 object = TAILQ_NEXT(object, object_list)) {
1810 if (object->handle == NULL &&
1811 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) {
1812 if (object->ref_count == 0) {
1813 db_printf("vmochk: internal obj has zero ref count: %ld\n",
1814 (long)object->size);
1815 }
1816 if (!vm_object_in_map(object)) {
1817 db_printf(
1818 "vmochk: internal obj is not in a map: "
1819 "ref: %d, size: %lu: 0x%lx, backing_object: %p\n",
1820 object->ref_count, (u_long)object->size,
1821 (u_long)object->size,
1822 (void *)object->backing_object);
1823 }
1824 }
1825 }
1826}
1827
1828/*
1829 * vm_object_print: [ debug ]
1830 */
1831DB_SHOW_COMMAND(object, vm_object_print_static)
1832{
1833 /* XXX convert args. */
1834 vm_object_t object = (vm_object_t)addr;
1835 boolean_t full = have_addr;
1836
1837 vm_page_t p;
1838
1839 /* XXX count is an (unused) arg. Avoid shadowing it. */
1840#define count was_count
1841
1842 int count;
1843
1844 if (object == NULL)
1845 return;
1846
1847 db_iprintf(
1848 "Object %p: type=%d, size=0x%lx, res=%d, ref=%d, flags=0x%x\n",
1849 object, (int)object->type, (u_long)object->size,
1850 object->resident_page_count, object->ref_count, object->flags);
1851 /*
1852 * XXX no %qd in kernel. Truncate object->backing_object_offset.
1853 */
1854 db_iprintf(" sref=%d, backing_object(%d)=(%p)+0x%lx\n",
1855 object->shadow_count,
1856 object->backing_object ? object->backing_object->ref_count : 0,
1857 object->backing_object, (long)object->backing_object_offset);
1858
1859 if (!full)
1860 return;
1861
1862 db_indent += 2;
1863 count = 0;
1864 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = TAILQ_NEXT(p, listq)) {
1865 if (count == 0)
1866 db_iprintf("memory:=");
1867 else if (count == 6) {
1868 db_printf("\n");
1869 db_iprintf(" ...");
1870 count = 0;
1871 } else
1872 db_printf(",");
1873 count++;
1874
1875 db_printf("(off=0x%lx,page=0x%lx)",
1876 (u_long) p->pindex, (u_long) VM_PAGE_TO_PHYS(p));
1877 }
1878 if (count != 0)
1879 db_printf("\n");
1880 db_indent -= 2;
1881}
1882
1883/* XXX. */
1884#undef count
1885
1886/* XXX need this non-static entry for calling from vm_map_print. */
1887void
1888vm_object_print(addr, have_addr, count, modif)
1889 /* db_expr_t */ long addr;
1890 boolean_t have_addr;
1891 /* db_expr_t */ long count;
1892 char *modif;
1893{
1894 vm_object_print_static(addr, have_addr, count, modif);
1895}
1896
1897DB_SHOW_COMMAND(vmopag, vm_object_print_pages)
1898{
1899 vm_object_t object;
1900 int nl = 0;
1901 int c;
1902 for (object = TAILQ_FIRST(&vm_object_list);
1903 object != NULL;
1904 object = TAILQ_NEXT(object, object_list)) {
1905 vm_pindex_t idx, fidx;
1906 vm_pindex_t osize;
1907 vm_offset_t pa = -1, padiff;
1908 int rcount;
1909 vm_page_t m;
1910
1911 db_printf("new object: %p\n", (void *)object);
1912 if ( nl > 18) {
1913 c = cngetc();
1914 if (c != ' ')
1915 return;
1916 nl = 0;
1917 }
1918 nl++;
1919 rcount = 0;
1920 fidx = 0;
1921 osize = object->size;
1922 if (osize > 128)
1923 osize = 128;
1924 for(idx=0;idx<osize;idx++) {
1925 m = vm_page_lookup(object, idx);
1926 if (m == NULL) {
1927 if (rcount) {
1928 db_printf(" index(%ld)run(%d)pa(0x%lx)\n",
1929 (long)fidx, rcount, (long)pa);
1930 if ( nl > 18) {
1931 c = cngetc();
1932 if (c != ' ')
1933 return;
1934 nl = 0;
1935 }
1936 nl++;
1937 rcount = 0;
1938 }
1939 continue;
1940 }
1941
1942
1943 if (rcount &&
1944 (VM_PAGE_TO_PHYS(m) == pa + rcount * PAGE_SIZE)) {
1945 ++rcount;
1946 continue;
1947 }
1948 if (rcount) {
1949 padiff = pa + rcount * PAGE_SIZE - VM_PAGE_TO_PHYS(m);
1950 padiff >>= PAGE_SHIFT;
1951 padiff &= PQ_L2_MASK;
1952 if (padiff == 0) {
1953 pa = VM_PAGE_TO_PHYS(m) - rcount * PAGE_SIZE;
1954 ++rcount;
1955 continue;
1956 }
1957 db_printf(" index(%ld)run(%d)pa(0x%lx)",
1958 (long)fidx, rcount, (long)pa);
1959 db_printf("pd(%ld)\n", (long)padiff);
1960 if ( nl > 18) {
1961 c = cngetc();
1962 if (c != ' ')
1963 return;
1964 nl = 0;
1965 }
1966 nl++;
1967 }
1968 fidx = idx;
1969 pa = VM_PAGE_TO_PHYS(m);
1970 rcount = 1;
1971 }
1972 if (rcount) {
1973 db_printf(" index(%ld)run(%d)pa(0x%lx)\n",
1974 (long)fidx, rcount, (long)pa);
1975 if ( nl > 18) {
1976 c = cngetc();
1977 if (c != ' ')
1978 return;
1979 nl = 0;
1980 }
1981 nl++;
1982 }
1983 }
1984}
1985#endif /* DDB */