229}
230
231void
232vm_object_set_flag(vm_object_t object, u_short bits)
233{
234 GIANT_REQUIRED;
235 object->flags |= bits;
236}
237
238void
239vm_object_clear_flag(vm_object_t object, u_short bits)
240{
241 GIANT_REQUIRED;
242 object->flags &= ~bits;
243}
244
245void
246vm_object_pip_add(vm_object_t object, short i)
247{
248 GIANT_REQUIRED;
249 object->paging_in_progress += i;
250}
251
252void
253vm_object_pip_subtract(vm_object_t object, short i)
254{
255 GIANT_REQUIRED;
256 object->paging_in_progress -= i;
257}
258
259void
260vm_object_pip_wakeup(vm_object_t object)
261{
262 GIANT_REQUIRED;
263 object->paging_in_progress--;
264 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
265 vm_object_clear_flag(object, OBJ_PIPWNT);
266 wakeup(object);
267 }
268}
269
270void
271vm_object_pip_wakeupn(vm_object_t object, short i)
272{
273 GIANT_REQUIRED;
274 if (i)
275 object->paging_in_progress -= i;
276 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
277 vm_object_clear_flag(object, OBJ_PIPWNT);
278 wakeup(object);
279 }
280}
281
282void
283vm_object_pip_sleep(vm_object_t object, char *waitid)
284{
285 GIANT_REQUIRED;
286 if (object->paging_in_progress) {
287 int s = splvm();
288 if (object->paging_in_progress) {
289 vm_object_set_flag(object, OBJ_PIPWNT);
290 tsleep(object, PVM, waitid, 0);
291 }
292 splx(s);
293 }
294}
295
296void
297vm_object_pip_wait(vm_object_t object, char *waitid)
298{
299 GIANT_REQUIRED;
300 while (object->paging_in_progress)
301 vm_object_pip_sleep(object, waitid);
302}
303
304/*
305 * vm_object_allocate:
306 *
307 * Returns a new object with the given size.
308 */
309vm_object_t
310vm_object_allocate(objtype_t type, vm_size_t size)
311{
312 vm_object_t result;
313
314 GIANT_REQUIRED;
315
316 result = (vm_object_t) zalloc(obj_zone);
317 _vm_object_allocate(type, size, result);
318
319 return (result);
320}
321
322
323/*
324 * vm_object_reference:
325 *
326 * Gets another reference to the given object.
327 */
328void
329vm_object_reference(vm_object_t object)
330{
331 GIANT_REQUIRED;
332
333 if (object == NULL)
334 return;
335
336#if 0
337 /* object can be re-referenced during final cleaning */
338 KASSERT(!(object->flags & OBJ_DEAD),
339 ("vm_object_reference: attempting to reference dead obj"));
340#endif
341
342 object->ref_count++;
343 if (object->type == OBJT_VNODE) {
344 while (vget((struct vnode *) object->handle, LK_RETRY|LK_NOOBJ, curthread)) {
345 printf("vm_object_reference: delay in getting object\n");
346 }
347 }
348}
349
350/*
351 * handle deallocating a object of type OBJT_VNODE
352 */
353void
354vm_object_vndeallocate(vm_object_t object)
355{
356 struct vnode *vp = (struct vnode *) object->handle;
357
358 GIANT_REQUIRED;
359 KASSERT(object->type == OBJT_VNODE,
360 ("vm_object_vndeallocate: not a vnode object"));
361 KASSERT(vp != NULL, ("vm_object_vndeallocate: missing vp"));
362#ifdef INVARIANTS
363 if (object->ref_count == 0) {
364 vprint("vm_object_vndeallocate", vp);
365 panic("vm_object_vndeallocate: bad object reference count");
366 }
367#endif
368
369 object->ref_count--;
370 if (object->ref_count == 0) {
371 vp->v_flag &= ~VTEXT;
372 vm_object_clear_flag(object, OBJ_OPT);
373 }
374 /*
375 * vrele may need a vop lock
376 */
377 vrele(vp);
378}
379
380/*
381 * vm_object_deallocate:
382 *
383 * Release a reference to the specified object,
384 * gained either through a vm_object_allocate
385 * or a vm_object_reference call. When all references
386 * are gone, storage associated with this object
387 * may be relinquished.
388 *
389 * No object may be locked.
390 */
391void
392vm_object_deallocate(vm_object_t object)
393{
394 vm_object_t temp;
395
396 GIANT_REQUIRED;
397
398 while (object != NULL) {
399
400 if (object->type == OBJT_VNODE) {
401 vm_object_vndeallocate(object);
402 return;
403 }
404
405 KASSERT(object->ref_count != 0,
406 ("vm_object_deallocate: object deallocated too many times: %d", object->type));
407
408 /*
409 * If the reference count goes to 0 we start calling
410 * vm_object_terminate() on the object chain.
411 * A ref count of 1 may be a special case depending on the
412 * shadow count being 0 or 1.
413 */
414 object->ref_count--;
415 if (object->ref_count > 1) {
416 return;
417 } else if (object->ref_count == 1) {
418 if (object->shadow_count == 0) {
419 vm_object_set_flag(object, OBJ_ONEMAPPING);
420 } else if ((object->shadow_count == 1) &&
421 (object->handle == NULL) &&
422 (object->type == OBJT_DEFAULT ||
423 object->type == OBJT_SWAP)) {
424 vm_object_t robject;
425
426 robject = TAILQ_FIRST(&object->shadow_head);
427 KASSERT(robject != NULL,
428 ("vm_object_deallocate: ref_count: %d, shadow_count: %d",
429 object->ref_count,
430 object->shadow_count));
431 if ((robject->handle == NULL) &&
432 (robject->type == OBJT_DEFAULT ||
433 robject->type == OBJT_SWAP)) {
434
435 robject->ref_count++;
436
437 while (
438 robject->paging_in_progress ||
439 object->paging_in_progress
440 ) {
441 vm_object_pip_sleep(robject, "objde1");
442 vm_object_pip_sleep(object, "objde2");
443 }
444
445 if (robject->ref_count == 1) {
446 robject->ref_count--;
447 object = robject;
448 goto doterm;
449 }
450
451 object = robject;
452 vm_object_collapse(object);
453 continue;
454 }
455 }
456
457 return;
458
459 }
460
461doterm:
462
463 temp = object->backing_object;
464 if (temp) {
465 TAILQ_REMOVE(&temp->shadow_head, object, shadow_list);
466 temp->shadow_count--;
467 if (temp->ref_count == 0)
468 vm_object_clear_flag(temp, OBJ_OPT);
469 temp->generation++;
470 object->backing_object = NULL;
471 }
472 /*
473 * Don't double-terminate, we could be in a termination
474 * recursion due to the terminate having to sync data
475 * to disk.
476 */
477 if ((object->flags & OBJ_DEAD) == 0)
478 vm_object_terminate(object);
479 object = temp;
480 }
481}
482
483/*
484 * vm_object_terminate actually destroys the specified object, freeing
485 * up all previously used resources.
486 *
487 * The object must be locked.
488 * This routine may block.
489 */
490void
491vm_object_terminate(vm_object_t object)
492{
493 vm_page_t p;
494 int s;
495
496 GIANT_REQUIRED;
497
498 /*
499 * Make sure no one uses us.
500 */
501 vm_object_set_flag(object, OBJ_DEAD);
502
503 /*
504 * wait for the pageout daemon to be done with the object
505 */
506 vm_object_pip_wait(object, "objtrm");
507
508 KASSERT(!object->paging_in_progress,
509 ("vm_object_terminate: pageout in progress"));
510
511 /*
512 * Clean and free the pages, as appropriate. All references to the
513 * object are gone, so we don't need to lock it.
514 */
515 if (object->type == OBJT_VNODE) {
516 struct vnode *vp;
517
518 /*
519 * Freeze optimized copies.
520 */
521 vm_freeze_copyopts(object, 0, object->size);
522
523 /*
524 * Clean pages and flush buffers.
525 */
526 vm_object_page_clean(object, 0, 0, OBJPC_SYNC);
527
528 vp = (struct vnode *) object->handle;
529 vinvalbuf(vp, V_SAVE, NOCRED, NULL, 0, 0);
530 }
531
532 KASSERT(object->ref_count == 0,
533 ("vm_object_terminate: object with references, ref_count=%d",
534 object->ref_count));
535
536 /*
537 * Now free any remaining pages. For internal objects, this also
538 * removes them from paging queues. Don't free wired pages, just
539 * remove them from the object.
540 */
541 s = splvm();
542 while ((p = TAILQ_FIRST(&object->memq)) != NULL) {
543 KASSERT(!p->busy && (p->flags & PG_BUSY) == 0,
544 ("vm_object_terminate: freeing busy page %p "
545 "p->busy = %d, p->flags %x\n", p, p->busy, p->flags));
546 if (p->wire_count == 0) {
547 vm_page_busy(p);
548 vm_page_free(p);
549 cnt.v_pfree++;
550 } else {
551 vm_page_busy(p);
552 vm_page_remove(p);
553 }
554 }
555 splx(s);
556
557 /*
558 * Let the pager know object is dead.
559 */
560 vm_pager_deallocate(object);
561
562 /*
563 * Remove the object from the global object list.
564 */
565 mtx_lock(&vm_object_list_mtx);
566 TAILQ_REMOVE(&vm_object_list, object, object_list);
567 mtx_unlock(&vm_object_list_mtx);
568
569 wakeup(object);
570
571 /*
572 * Free the space for the object.
573 */
574 zfree(obj_zone, object);
575}
576
577/*
578 * vm_object_page_clean
579 *
580 * Clean all dirty pages in the specified range of object. Leaves page
581 * on whatever queue it is currently on. If NOSYNC is set then do not
582 * write out pages with PG_NOSYNC set (originally comes from MAP_NOSYNC),
583 * leaving the object dirty.
584 *
585 * Odd semantics: if start == end, we clean everything.
586 *
587 * The object must be locked.
588 */
589void
590vm_object_page_clean(vm_object_t object, vm_pindex_t start, vm_pindex_t end, int flags)
591{
592 vm_page_t p, np;
593 vm_offset_t tstart, tend;
594 vm_pindex_t pi;
595 struct vnode *vp;
596 int clearobjflags;
597 int pagerflags;
598 int curgeneration;
599
600 GIANT_REQUIRED;
601
602 if (object->type != OBJT_VNODE ||
603 (object->flags & OBJ_MIGHTBEDIRTY) == 0)
604 return;
605
606 pagerflags = (flags & (OBJPC_SYNC | OBJPC_INVAL)) ? VM_PAGER_PUT_SYNC : 0;
607 pagerflags |= (flags & OBJPC_INVAL) ? VM_PAGER_PUT_INVAL : 0;
608
609 vp = object->handle;
610
611 vm_object_set_flag(object, OBJ_CLEANING);
612
613 tstart = start;
614 if (end == 0) {
615 tend = object->size;
616 } else {
617 tend = end;
618 }
619
620 /*
621 * If the caller is smart and only msync()s a range he knows is
622 * dirty, we may be able to avoid an object scan. This results in
623 * a phenominal improvement in performance. We cannot do this
624 * as a matter of course because the object may be huge - e.g.
625 * the size might be in the gigabytes or terrabytes.
626 */
627 if (msync_flush_flags & MSYNC_FLUSH_HARDSEQ) {
628 vm_offset_t tscan;
629 int scanlimit;
630 int scanreset;
631
632 scanreset = object->resident_page_count / EASY_SCAN_FACTOR;
633 if (scanreset < 16)
634 scanreset = 16;
635
636 scanlimit = scanreset;
637 tscan = tstart;
638 while (tscan < tend) {
639 curgeneration = object->generation;
640 p = vm_page_lookup(object, tscan);
641 if (p == NULL || p->valid == 0 ||
642 (p->queue - p->pc) == PQ_CACHE) {
643 if (--scanlimit == 0)
644 break;
645 ++tscan;
646 continue;
647 }
648 vm_page_test_dirty(p);
649 if ((p->dirty & p->valid) == 0) {
650 if (--scanlimit == 0)
651 break;
652 ++tscan;
653 continue;
654 }
655 /*
656 * If we have been asked to skip nosync pages and
657 * this is a nosync page, we can't continue.
658 */
659 if ((flags & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) {
660 if (--scanlimit == 0)
661 break;
662 ++tscan;
663 continue;
664 }
665 scanlimit = scanreset;
666
667 /*
668 * This returns 0 if it was unable to busy the first
669 * page (i.e. had to sleep).
670 */
671 tscan += vm_object_page_collect_flush(object, p, curgeneration, pagerflags);
672 }
673
674 /*
675 * If everything was dirty and we flushed it successfully,
676 * and the requested range is not the entire object, we
677 * don't have to mess with CLEANCHK or MIGHTBEDIRTY and can
678 * return immediately.
679 */
680 if (tscan >= tend && (tstart || tend < object->size)) {
681 vm_object_clear_flag(object, OBJ_CLEANING);
682 return;
683 }
684 }
685
686 /*
687 * Generally set CLEANCHK interlock and make the page read-only so
688 * we can then clear the object flags.
689 *
690 * However, if this is a nosync mmap then the object is likely to
691 * stay dirty so do not mess with the page and do not clear the
692 * object flags.
693 */
694 clearobjflags = 1;
695
696 TAILQ_FOREACH(p, &object->memq, listq) {
697 vm_page_flag_set(p, PG_CLEANCHK);
698 if ((flags & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC))
699 clearobjflags = 0;
700 else
701 vm_page_protect(p, VM_PROT_READ);
702 }
703
704 if (clearobjflags && (tstart == 0) && (tend == object->size)) {
705 struct vnode *vp;
706
707 vm_object_clear_flag(object, OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY);
708 if (object->type == OBJT_VNODE &&
709 (vp = (struct vnode *)object->handle) != NULL) {
710 if (vp->v_flag & VOBJDIRTY) {
711 mtx_lock(&vp->v_interlock);
712 vp->v_flag &= ~VOBJDIRTY;
713 mtx_unlock(&vp->v_interlock);
714 }
715 }
716 }
717
718rescan:
719 curgeneration = object->generation;
720
721 for (p = TAILQ_FIRST(&object->memq); p; p = np) {
722 int n;
723
724 np = TAILQ_NEXT(p, listq);
725
726again:
727 pi = p->pindex;
728 if (((p->flags & PG_CLEANCHK) == 0) ||
729 (pi < tstart) || (pi >= tend) ||
730 (p->valid == 0) ||
731 ((p->queue - p->pc) == PQ_CACHE)) {
732 vm_page_flag_clear(p, PG_CLEANCHK);
733 continue;
734 }
735
736 vm_page_test_dirty(p);
737 if ((p->dirty & p->valid) == 0) {
738 vm_page_flag_clear(p, PG_CLEANCHK);
739 continue;
740 }
741
742 /*
743 * If we have been asked to skip nosync pages and this is a
744 * nosync page, skip it. Note that the object flags were
745 * not cleared in this case so we do not have to set them.
746 */
747 if ((flags & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) {
748 vm_page_flag_clear(p, PG_CLEANCHK);
749 continue;
750 }
751
752 n = vm_object_page_collect_flush(object, p,
753 curgeneration, pagerflags);
754 if (n == 0)
755 goto rescan;
756
757 if (object->generation != curgeneration)
758 goto rescan;
759
760 /*
761 * Try to optimize the next page. If we can't we pick up
762 * our (random) scan where we left off.
763 */
764 if (msync_flush_flags & MSYNC_FLUSH_SOFTSEQ) {
765 if ((p = vm_page_lookup(object, pi + n)) != NULL)
766 goto again;
767 }
768 }
769
770#if 0
771 VOP_FSYNC(vp, NULL, (pagerflags & VM_PAGER_PUT_SYNC)?MNT_WAIT:0, curproc);
772#endif
773
774 vm_object_clear_flag(object, OBJ_CLEANING);
775 return;
776}
777
778static int
779vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int curgeneration, int pagerflags)
780{
781 int runlen;
782 int s;
783 int maxf;
784 int chkb;
785 int maxb;
786 int i;
787 vm_pindex_t pi;
788 vm_page_t maf[vm_pageout_page_count];
789 vm_page_t mab[vm_pageout_page_count];
790 vm_page_t ma[vm_pageout_page_count];
791
792 s = splvm();
793 pi = p->pindex;
794 while (vm_page_sleep_busy(p, TRUE, "vpcwai")) {
795 if (object->generation != curgeneration) {
796 splx(s);
797 return(0);
798 }
799 }
800
801 maxf = 0;
802 for(i = 1; i < vm_pageout_page_count; i++) {
803 vm_page_t tp;
804
805 if ((tp = vm_page_lookup(object, pi + i)) != NULL) {
806 if ((tp->flags & PG_BUSY) ||
807 (tp->flags & PG_CLEANCHK) == 0 ||
808 (tp->busy != 0))
809 break;
810 if((tp->queue - tp->pc) == PQ_CACHE) {
811 vm_page_flag_clear(tp, PG_CLEANCHK);
812 break;
813 }
814 vm_page_test_dirty(tp);
815 if ((tp->dirty & tp->valid) == 0) {
816 vm_page_flag_clear(tp, PG_CLEANCHK);
817 break;
818 }
819 maf[ i - 1 ] = tp;
820 maxf++;
821 continue;
822 }
823 break;
824 }
825
826 maxb = 0;
827 chkb = vm_pageout_page_count - maxf;
828 if (chkb) {
829 for(i = 1; i < chkb;i++) {
830 vm_page_t tp;
831
832 if ((tp = vm_page_lookup(object, pi - i)) != NULL) {
833 if ((tp->flags & PG_BUSY) ||
834 (tp->flags & PG_CLEANCHK) == 0 ||
835 (tp->busy != 0))
836 break;
837 if ((tp->queue - tp->pc) == PQ_CACHE) {
838 vm_page_flag_clear(tp, PG_CLEANCHK);
839 break;
840 }
841 vm_page_test_dirty(tp);
842 if ((tp->dirty & tp->valid) == 0) {
843 vm_page_flag_clear(tp, PG_CLEANCHK);
844 break;
845 }
846 mab[ i - 1 ] = tp;
847 maxb++;
848 continue;
849 }
850 break;
851 }
852 }
853
854 for(i = 0; i < maxb; i++) {
855 int index = (maxb - i) - 1;
856 ma[index] = mab[i];
857 vm_page_flag_clear(ma[index], PG_CLEANCHK);
858 }
859 vm_page_flag_clear(p, PG_CLEANCHK);
860 ma[maxb] = p;
861 for(i = 0; i < maxf; i++) {
862 int index = (maxb + i) + 1;
863 ma[index] = maf[i];
864 vm_page_flag_clear(ma[index], PG_CLEANCHK);
865 }
866 runlen = maxb + maxf + 1;
867
868 splx(s);
869 vm_pageout_flush(ma, runlen, pagerflags);
870 for (i = 0; i < runlen; i++) {
871 if (ma[i]->valid & ma[i]->dirty) {
872 vm_page_protect(ma[i], VM_PROT_READ);
873 vm_page_flag_set(ma[i], PG_CLEANCHK);
874
875 /*
876 * maxf will end up being the actual number of pages
877 * we wrote out contiguously, non-inclusive of the
878 * first page. We do not count look-behind pages.
879 */
880 if (i >= maxb + 1 && (maxf > i - maxb - 1))
881 maxf = i - maxb - 1;
882 }
883 }
884 return(maxf + 1);
885}
886
887/*
888 * Same as vm_object_pmap_copy, except range checking really
889 * works, and is meant for small sections of an object.
890 *
891 * This code protects resident pages by making them read-only
892 * and is typically called on a fork or split when a page
893 * is converted to copy-on-write.
894 *
895 * NOTE: If the page is already at VM_PROT_NONE, calling
896 * vm_page_protect will have no effect.
897 */
898void
899vm_object_pmap_copy_1(vm_object_t object, vm_pindex_t start, vm_pindex_t end)
900{
901 vm_pindex_t idx;
902 vm_page_t p;
903
904 GIANT_REQUIRED;
905
906 if (object == NULL || (object->flags & OBJ_WRITEABLE) == 0)
907 return;
908
909 for (idx = start; idx < end; idx++) {
910 p = vm_page_lookup(object, idx);
911 if (p == NULL)
912 continue;
913 vm_page_protect(p, VM_PROT_READ);
914 }
915}
916
917/*
918 * vm_object_pmap_remove:
919 *
920 * Removes all physical pages in the specified
921 * object range from all physical maps.
922 *
923 * The object must *not* be locked.
924 */
925void
926vm_object_pmap_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end)
927{
928 vm_page_t p;
929
930 GIANT_REQUIRED;
931 if (object == NULL)
932 return;
933 TAILQ_FOREACH(p, &object->memq, listq) {
934 if (p->pindex >= start && p->pindex < end)
935 vm_page_protect(p, VM_PROT_NONE);
936 }
937 if ((start == 0) && (object->size == end))
938 vm_object_clear_flag(object, OBJ_WRITEABLE);
939}
940
941/*
942 * vm_object_madvise:
943 *
944 * Implements the madvise function at the object/page level.
945 *
946 * MADV_WILLNEED (any object)
947 *
948 * Activate the specified pages if they are resident.
949 *
950 * MADV_DONTNEED (any object)
951 *
952 * Deactivate the specified pages if they are resident.
953 *
954 * MADV_FREE (OBJT_DEFAULT/OBJT_SWAP objects,
955 * OBJ_ONEMAPPING only)
956 *
957 * Deactivate and clean the specified pages if they are
958 * resident. This permits the process to reuse the pages
959 * without faulting or the kernel to reclaim the pages
960 * without I/O.
961 */
962void
963vm_object_madvise(vm_object_t object, vm_pindex_t pindex, int count, int advise)
964{
965 vm_pindex_t end, tpindex;
966 vm_object_t tobject;
967 vm_page_t m;
968
969 GIANT_REQUIRED;
970 if (object == NULL)
971 return;
972
973 end = pindex + count;
974
975 /*
976 * Locate and adjust resident pages
977 */
978 for (; pindex < end; pindex += 1) {
979relookup:
980 tobject = object;
981 tpindex = pindex;
982shadowlookup:
983 /*
984 * MADV_FREE only operates on OBJT_DEFAULT or OBJT_SWAP pages
985 * and those pages must be OBJ_ONEMAPPING.
986 */
987 if (advise == MADV_FREE) {
988 if ((tobject->type != OBJT_DEFAULT &&
989 tobject->type != OBJT_SWAP) ||
990 (tobject->flags & OBJ_ONEMAPPING) == 0) {
991 continue;
992 }
993 }
994
995 m = vm_page_lookup(tobject, tpindex);
996
997 if (m == NULL) {
998 /*
999 * There may be swap even if there is no backing page
1000 */
1001 if (advise == MADV_FREE && tobject->type == OBJT_SWAP)
1002 swap_pager_freespace(tobject, tpindex, 1);
1003
1004 /*
1005 * next object
1006 */
1007 tobject = tobject->backing_object;
1008 if (tobject == NULL)
1009 continue;
1010 tpindex += OFF_TO_IDX(tobject->backing_object_offset);
1011 goto shadowlookup;
1012 }
1013
1014 /*
1015 * If the page is busy or not in a normal active state,
1016 * we skip it. If the page is not managed there are no
1017 * page queues to mess with. Things can break if we mess
1018 * with pages in any of the below states.
1019 */
1020 if (
1021 m->hold_count ||
1022 m->wire_count ||
1023 (m->flags & PG_UNMANAGED) ||
1024 m->valid != VM_PAGE_BITS_ALL
1025 ) {
1026 continue;
1027 }
1028
1029 if (vm_page_sleep_busy(m, TRUE, "madvpo"))
1030 goto relookup;
1031
1032 if (advise == MADV_WILLNEED) {
1033 vm_page_activate(m);
1034 } else if (advise == MADV_DONTNEED) {
1035 vm_page_dontneed(m);
1036 } else if (advise == MADV_FREE) {
1037 /*
1038 * Mark the page clean. This will allow the page
1039 * to be freed up by the system. However, such pages
1040 * are often reused quickly by malloc()/free()
1041 * so we do not do anything that would cause
1042 * a page fault if we can help it.
1043 *
1044 * Specifically, we do not try to actually free
1045 * the page now nor do we try to put it in the
1046 * cache (which would cause a page fault on reuse).
1047 *
1048 * But we do make the page is freeable as we
1049 * can without actually taking the step of unmapping
1050 * it.
1051 */
1052 pmap_clear_modify(m);
1053 m->dirty = 0;
1054 m->act_count = 0;
1055 vm_page_dontneed(m);
1056 if (tobject->type == OBJT_SWAP)
1057 swap_pager_freespace(tobject, tpindex, 1);
1058 }
1059 }
1060}
1061
1062/*
1063 * vm_object_shadow:
1064 *
1065 * Create a new object which is backed by the
1066 * specified existing object range. The source
1067 * object reference is deallocated.
1068 *
1069 * The new object and offset into that object
1070 * are returned in the source parameters.
1071 */
1072void
1073vm_object_shadow(
1074 vm_object_t *object, /* IN/OUT */
1075 vm_ooffset_t *offset, /* IN/OUT */
1076 vm_size_t length)
1077{
1078 vm_object_t source;
1079 vm_object_t result;
1080
1081 GIANT_REQUIRED;
1082 source = *object;
1083
1084 /*
1085 * Don't create the new object if the old object isn't shared.
1086 */
1087 if (source != NULL &&
1088 source->ref_count == 1 &&
1089 source->handle == NULL &&
1090 (source->type == OBJT_DEFAULT ||
1091 source->type == OBJT_SWAP))
1092 return;
1093
1094 /*
1095 * Allocate a new object with the given length
1096 */
1097 result = vm_object_allocate(OBJT_DEFAULT, length);
1098 KASSERT(result != NULL, ("vm_object_shadow: no object for shadowing"));
1099
1100 /*
1101 * The new object shadows the source object, adding a reference to it.
1102 * Our caller changes his reference to point to the new object,
1103 * removing a reference to the source object. Net result: no change
1104 * of reference count.
1105 *
1106 * Try to optimize the result object's page color when shadowing
1107 * in order to maintain page coloring consistency in the combined
1108 * shadowed object.
1109 */
1110 result->backing_object = source;
1111 if (source) {
1112 TAILQ_INSERT_TAIL(&source->shadow_head, result, shadow_list);
1113 source->shadow_count++;
1114 source->generation++;
1115 result->pg_color = (source->pg_color + OFF_TO_IDX(*offset)) & PQ_L2_MASK;
1116 }
1117
1118 /*
1119 * Store the offset into the source object, and fix up the offset into
1120 * the new object.
1121 */
1122 result->backing_object_offset = *offset;
1123
1124 /*
1125 * Return the new things
1126 */
1127 *offset = 0;
1128 *object = result;
1129}
1130
1131#define OBSC_TEST_ALL_SHADOWED 0x0001
1132#define OBSC_COLLAPSE_NOWAIT 0x0002
1133#define OBSC_COLLAPSE_WAIT 0x0004
1134
1135static __inline int
1136vm_object_backing_scan(vm_object_t object, int op)
1137{
1138 int s;
1139 int r = 1;
1140 vm_page_t p;
1141 vm_object_t backing_object;
1142 vm_pindex_t backing_offset_index;
1143
1144 s = splvm();
1145 GIANT_REQUIRED;
1146
1147 backing_object = object->backing_object;
1148 backing_offset_index = OFF_TO_IDX(object->backing_object_offset);
1149
1150 /*
1151 * Initial conditions
1152 */
1153 if (op & OBSC_TEST_ALL_SHADOWED) {
1154 /*
1155 * We do not want to have to test for the existence of
1156 * swap pages in the backing object. XXX but with the
1157 * new swapper this would be pretty easy to do.
1158 *
1159 * XXX what about anonymous MAP_SHARED memory that hasn't
1160 * been ZFOD faulted yet? If we do not test for this, the
1161 * shadow test may succeed! XXX
1162 */
1163 if (backing_object->type != OBJT_DEFAULT) {
1164 splx(s);
1165 return (0);
1166 }
1167 }
1168 if (op & OBSC_COLLAPSE_WAIT) {
1169 vm_object_set_flag(backing_object, OBJ_DEAD);
1170 }
1171
1172 /*
1173 * Our scan
1174 */
1175 p = TAILQ_FIRST(&backing_object->memq);
1176 while (p) {
1177 vm_page_t next = TAILQ_NEXT(p, listq);
1178 vm_pindex_t new_pindex = p->pindex - backing_offset_index;
1179
1180 if (op & OBSC_TEST_ALL_SHADOWED) {
1181 vm_page_t pp;
1182
1183 /*
1184 * Ignore pages outside the parent object's range
1185 * and outside the parent object's mapping of the
1186 * backing object.
1187 *
1188 * note that we do not busy the backing object's
1189 * page.
1190 */
1191 if (
1192 p->pindex < backing_offset_index ||
1193 new_pindex >= object->size
1194 ) {
1195 p = next;
1196 continue;
1197 }
1198
1199 /*
1200 * See if the parent has the page or if the parent's
1201 * object pager has the page. If the parent has the
1202 * page but the page is not valid, the parent's
1203 * object pager must have the page.
1204 *
1205 * If this fails, the parent does not completely shadow
1206 * the object and we might as well give up now.
1207 */
1208
1209 pp = vm_page_lookup(object, new_pindex);
1210 if (
1211 (pp == NULL || pp->valid == 0) &&
1212 !vm_pager_has_page(object, new_pindex, NULL, NULL)
1213 ) {
1214 r = 0;
1215 break;
1216 }
1217 }
1218
1219 /*
1220 * Check for busy page
1221 */
1222 if (op & (OBSC_COLLAPSE_WAIT | OBSC_COLLAPSE_NOWAIT)) {
1223 vm_page_t pp;
1224
1225 if (op & OBSC_COLLAPSE_NOWAIT) {
1226 if (
1227 (p->flags & PG_BUSY) ||
1228 !p->valid ||
1229 p->hold_count ||
1230 p->wire_count ||
1231 p->busy
1232 ) {
1233 p = next;
1234 continue;
1235 }
1236 } else if (op & OBSC_COLLAPSE_WAIT) {
1237 if (vm_page_sleep_busy(p, TRUE, "vmocol")) {
1238 /*
1239 * If we slept, anything could have
1240 * happened. Since the object is
1241 * marked dead, the backing offset
1242 * should not have changed so we
1243 * just restart our scan.
1244 */
1245 p = TAILQ_FIRST(&backing_object->memq);
1246 continue;
1247 }
1248 }
1249
1250 /*
1251 * Busy the page
1252 */
1253 vm_page_busy(p);
1254
1255 KASSERT(
1256 p->object == backing_object,
1257 ("vm_object_qcollapse(): object mismatch")
1258 );
1259
1260 /*
1261 * Destroy any associated swap
1262 */
1263 if (backing_object->type == OBJT_SWAP) {
1264 swap_pager_freespace(
1265 backing_object,
1266 p->pindex,
1267 1
1268 );
1269 }
1270
1271 if (
1272 p->pindex < backing_offset_index ||
1273 new_pindex >= object->size
1274 ) {
1275 /*
1276 * Page is out of the parent object's range, we
1277 * can simply destroy it.
1278 */
1279 vm_page_protect(p, VM_PROT_NONE);
1280 vm_page_free(p);
1281 p = next;
1282 continue;
1283 }
1284
1285 pp = vm_page_lookup(object, new_pindex);
1286 if (
1287 pp != NULL ||
1288 vm_pager_has_page(object, new_pindex, NULL, NULL)
1289 ) {
1290 /*
1291 * page already exists in parent OR swap exists
1292 * for this location in the parent. Destroy
1293 * the original page from the backing object.
1294 *
1295 * Leave the parent's page alone
1296 */
1297 vm_page_protect(p, VM_PROT_NONE);
1298 vm_page_free(p);
1299 p = next;
1300 continue;
1301 }
1302
1303 /*
1304 * Page does not exist in parent, rename the
1305 * page from the backing object to the main object.
1306 *
1307 * If the page was mapped to a process, it can remain
1308 * mapped through the rename.
1309 */
1310 if ((p->queue - p->pc) == PQ_CACHE)
1311 vm_page_deactivate(p);
1312
1313 vm_page_rename(p, object, new_pindex);
1314 /* page automatically made dirty by rename */
1315 }
1316 p = next;
1317 }
1318 splx(s);
1319 return (r);
1320}
1321
1322
1323/*
1324 * this version of collapse allows the operation to occur earlier and
1325 * when paging_in_progress is true for an object... This is not a complete
1326 * operation, but should plug 99.9% of the rest of the leaks.
1327 */
1328static void
1329vm_object_qcollapse(vm_object_t object)
1330{
1331 vm_object_t backing_object = object->backing_object;
1332
1333 GIANT_REQUIRED;
1334
1335 if (backing_object->ref_count != 1)
1336 return;
1337
1338 backing_object->ref_count += 2;
1339
1340 vm_object_backing_scan(object, OBSC_COLLAPSE_NOWAIT);
1341
1342 backing_object->ref_count -= 2;
1343}
1344
1345/*
1346 * vm_object_collapse:
1347 *
1348 * Collapse an object with the object backing it.
1349 * Pages in the backing object are moved into the
1350 * parent, and the backing object is deallocated.
1351 */
1352void
1353vm_object_collapse(vm_object_t object)
1354{
1355 GIANT_REQUIRED;
1356
1357 while (TRUE) {
1358 vm_object_t backing_object;
1359
1360 /*
1361 * Verify that the conditions are right for collapse:
1362 *
1363 * The object exists and the backing object exists.
1364 */
1365 if (object == NULL)
1366 break;
1367
1368 if ((backing_object = object->backing_object) == NULL)
1369 break;
1370
1371 /*
1372 * we check the backing object first, because it is most likely
1373 * not collapsable.
1374 */
1375 if (backing_object->handle != NULL ||
1376 (backing_object->type != OBJT_DEFAULT &&
1377 backing_object->type != OBJT_SWAP) ||
1378 (backing_object->flags & OBJ_DEAD) ||
1379 object->handle != NULL ||
1380 (object->type != OBJT_DEFAULT &&
1381 object->type != OBJT_SWAP) ||
1382 (object->flags & OBJ_DEAD)) {
1383 break;
1384 }
1385
1386 if (
1387 object->paging_in_progress != 0 ||
1388 backing_object->paging_in_progress != 0
1389 ) {
1390 vm_object_qcollapse(object);
1391 break;
1392 }
1393
1394 /*
1395 * We know that we can either collapse the backing object (if
1396 * the parent is the only reference to it) or (perhaps) have
1397 * the parent bypass the object if the parent happens to shadow
1398 * all the resident pages in the entire backing object.
1399 *
1400 * This is ignoring pager-backed pages such as swap pages.
1401 * vm_object_backing_scan fails the shadowing test in this
1402 * case.
1403 */
1404 if (backing_object->ref_count == 1) {
1405 /*
1406 * If there is exactly one reference to the backing
1407 * object, we can collapse it into the parent.
1408 */
1409 vm_object_backing_scan(object, OBSC_COLLAPSE_WAIT);
1410
1411 /*
1412 * Move the pager from backing_object to object.
1413 */
1414 if (backing_object->type == OBJT_SWAP) {
1415 vm_object_pip_add(backing_object, 1);
1416
1417 /*
1418 * scrap the paging_offset junk and do a
1419 * discrete copy. This also removes major
1420 * assumptions about how the swap-pager
1421 * works from where it doesn't belong. The
1422 * new swapper is able to optimize the
1423 * destroy-source case.
1424 */
1425 vm_object_pip_add(object, 1);
1426 swap_pager_copy(
1427 backing_object,
1428 object,
1429 OFF_TO_IDX(object->backing_object_offset), TRUE);
1430 vm_object_pip_wakeup(object);
1431
1432 vm_object_pip_wakeup(backing_object);
1433 }
1434 /*
1435 * Object now shadows whatever backing_object did.
1436 * Note that the reference to
1437 * backing_object->backing_object moves from within
1438 * backing_object to within object.
1439 */
1440 TAILQ_REMOVE(
1441 &object->backing_object->shadow_head,
1442 object,
1443 shadow_list
1444 );
1445 object->backing_object->shadow_count--;
1446 object->backing_object->generation++;
1447 if (backing_object->backing_object) {
1448 TAILQ_REMOVE(
1449 &backing_object->backing_object->shadow_head,
1450 backing_object,
1451 shadow_list
1452 );
1453 backing_object->backing_object->shadow_count--;
1454 backing_object->backing_object->generation++;
1455 }
1456 object->backing_object = backing_object->backing_object;
1457 if (object->backing_object) {
1458 TAILQ_INSERT_TAIL(
1459 &object->backing_object->shadow_head,
1460 object,
1461 shadow_list
1462 );
1463 object->backing_object->shadow_count++;
1464 object->backing_object->generation++;
1465 }
1466
1467 object->backing_object_offset +=
1468 backing_object->backing_object_offset;
1469
1470 /*
1471 * Discard backing_object.
1472 *
1473 * Since the backing object has no pages, no pager left,
1474 * and no object references within it, all that is
1475 * necessary is to dispose of it.
1476 */
1477 KASSERT(backing_object->ref_count == 1, ("backing_object %p was somehow re-referenced during collapse!", backing_object));
1478 KASSERT(TAILQ_FIRST(&backing_object->memq) == NULL, ("backing_object %p somehow has left over pages during collapse!", backing_object));
1479
1480 TAILQ_REMOVE(
1481 &vm_object_list,
1482 backing_object,
1483 object_list
1484 );
1485
1486 zfree(obj_zone, backing_object);
1487
1488 object_collapses++;
1489 } else {
1490 vm_object_t new_backing_object;
1491
1492 /*
1493 * If we do not entirely shadow the backing object,
1494 * there is nothing we can do so we give up.
1495 */
1496 if (vm_object_backing_scan(object, OBSC_TEST_ALL_SHADOWED) == 0) {
1497 break;
1498 }
1499
1500 /*
1501 * Make the parent shadow the next object in the
1502 * chain. Deallocating backing_object will not remove
1503 * it, since its reference count is at least 2.
1504 */
1505 TAILQ_REMOVE(
1506 &backing_object->shadow_head,
1507 object,
1508 shadow_list
1509 );
1510 backing_object->shadow_count--;
1511 backing_object->generation++;
1512
1513 new_backing_object = backing_object->backing_object;
1514 if ((object->backing_object = new_backing_object) != NULL) {
1515 vm_object_reference(new_backing_object);
1516 TAILQ_INSERT_TAIL(
1517 &new_backing_object->shadow_head,
1518 object,
1519 shadow_list
1520 );
1521 new_backing_object->shadow_count++;
1522 new_backing_object->generation++;
1523 object->backing_object_offset +=
1524 backing_object->backing_object_offset;
1525 }
1526
1527 /*
1528 * Drop the reference count on backing_object. Since
1529 * its ref_count was at least 2, it will not vanish;
1530 * so we don't need to call vm_object_deallocate, but
1531 * we do anyway.
1532 */
1533 vm_object_deallocate(backing_object);
1534 object_bypasses++;
1535 }
1536
1537 /*
1538 * Try again with this object's new backing object.
1539 */
1540 }
1541}
1542
1543/*
1544 * vm_object_page_remove: [internal]
1545 *
1546 * Removes all physical pages in the specified
1547 * object range from the object's list of pages.
1548 *
1549 * The object must be locked.
1550 */
1551void
1552vm_object_page_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end, boolean_t clean_only)
1553{
1554 vm_page_t p, next;
1555 unsigned int size;
1556 int all;
1557
1558 GIANT_REQUIRED;
1559
1560 if (object == NULL ||
1561 object->resident_page_count == 0)
1562 return;
1563
1564 all = ((end == 0) && (start == 0));
1565
1566 /*
1567 * Since physically-backed objects do not use managed pages, we can't
1568 * remove pages from the object (we must instead remove the page
1569 * references, and then destroy the object).
1570 */
1571 KASSERT(object->type != OBJT_PHYS, ("attempt to remove pages from a physical object"));
1572
1573 vm_object_pip_add(object, 1);
1574again:
1575 size = end - start;
1576 if (all || size > object->resident_page_count / 4) {
1577 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = next) {
1578 next = TAILQ_NEXT(p, listq);
1579 if (all || ((start <= p->pindex) && (p->pindex < end))) {
1580 if (p->wire_count != 0) {
1581 vm_page_protect(p, VM_PROT_NONE);
1582 if (!clean_only)
1583 p->valid = 0;
1584 continue;
1585 }
1586
1587 /*
1588 * The busy flags are only cleared at
1589 * interrupt -- minimize the spl transitions
1590 */
1591 if (vm_page_sleep_busy(p, TRUE, "vmopar"))
1592 goto again;
1593
1594 if (clean_only && p->valid) {
1595 vm_page_test_dirty(p);
1596 if (p->valid & p->dirty)
1597 continue;
1598 }
1599
1600 vm_page_busy(p);
1601 vm_page_protect(p, VM_PROT_NONE);
1602 vm_page_free(p);
1603 }
1604 }
1605 } else {
1606 while (size > 0) {
1607 if ((p = vm_page_lookup(object, start)) != 0) {
1608
1609 if (p->wire_count != 0) {
1610 vm_page_protect(p, VM_PROT_NONE);
1611 if (!clean_only)
1612 p->valid = 0;
1613 start += 1;
1614 size -= 1;
1615 continue;
1616 }
1617
1618 /*
1619 * The busy flags are only cleared at
1620 * interrupt -- minimize the spl transitions
1621 */
1622 if (vm_page_sleep_busy(p, TRUE, "vmopar"))
1623 goto again;
1624
1625 if (clean_only && p->valid) {
1626 vm_page_test_dirty(p);
1627 if (p->valid & p->dirty) {
1628 start += 1;
1629 size -= 1;
1630 continue;
1631 }
1632 }
1633
1634 vm_page_busy(p);
1635 vm_page_protect(p, VM_PROT_NONE);
1636 vm_page_free(p);
1637 }
1638 start += 1;
1639 size -= 1;
1640 }
1641 }
1642 vm_object_pip_wakeup(object);
1643}
1644
1645/*
1646 * Routine: vm_object_coalesce
1647 * Function: Coalesces two objects backing up adjoining
1648 * regions of memory into a single object.
1649 *
1650 * returns TRUE if objects were combined.
1651 *
1652 * NOTE: Only works at the moment if the second object is NULL -
1653 * if it's not, which object do we lock first?
1654 *
1655 * Parameters:
1656 * prev_object First object to coalesce
1657 * prev_offset Offset into prev_object
1658 * next_object Second object into coalesce
1659 * next_offset Offset into next_object
1660 *
1661 * prev_size Size of reference to prev_object
1662 * next_size Size of reference to next_object
1663 *
1664 * Conditions:
1665 * The object must *not* be locked.
1666 */
1667boolean_t
1668vm_object_coalesce(vm_object_t prev_object, vm_pindex_t prev_pindex, vm_size_t prev_size, vm_size_t next_size)
1669{
1670 vm_pindex_t next_pindex;
1671
1672 GIANT_REQUIRED;
1673
1674 if (prev_object == NULL) {
1675 return (TRUE);
1676 }
1677
1678 if (prev_object->type != OBJT_DEFAULT &&
1679 prev_object->type != OBJT_SWAP) {
1680 return (FALSE);
1681 }
1682
1683 /*
1684 * Try to collapse the object first
1685 */
1686 vm_object_collapse(prev_object);
1687
1688 /*
1689 * Can't coalesce if: . more than one reference . paged out . shadows
1690 * another object . has a copy elsewhere (any of which mean that the
1691 * pages not mapped to prev_entry may be in use anyway)
1692 */
1693 if (prev_object->backing_object != NULL) {
1694 return (FALSE);
1695 }
1696
1697 prev_size >>= PAGE_SHIFT;
1698 next_size >>= PAGE_SHIFT;
1699 next_pindex = prev_pindex + prev_size;
1700
1701 if ((prev_object->ref_count > 1) &&
1702 (prev_object->size != next_pindex)) {
1703 return (FALSE);
1704 }
1705
1706 /*
1707 * Remove any pages that may still be in the object from a previous
1708 * deallocation.
1709 */
1710 if (next_pindex < prev_object->size) {
1711 vm_object_page_remove(prev_object,
1712 next_pindex,
1713 next_pindex + next_size, FALSE);
1714 if (prev_object->type == OBJT_SWAP)
1715 swap_pager_freespace(prev_object,
1716 next_pindex, next_size);
1717 }
1718
1719 /*
1720 * Extend the object if necessary.
1721 */
1722 if (next_pindex + next_size > prev_object->size)
1723 prev_object->size = next_pindex + next_size;
1724
1725 return (TRUE);
1726}
1727
1728void
1729vm_object_set_writeable_dirty(vm_object_t object)
1730{
1731 struct vnode *vp;
1732
1733 vm_object_set_flag(object, OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY);
1734 if (object->type == OBJT_VNODE &&
1735 (vp = (struct vnode *)object->handle) != NULL) {
1736 if ((vp->v_flag & VOBJDIRTY) == 0) {
1737 mtx_lock(&vp->v_interlock);
1738 vp->v_flag |= VOBJDIRTY;
1739 mtx_unlock(&vp->v_interlock);
1740 }
1741 }
1742}
1743
1744#include "opt_ddb.h"
1745#ifdef DDB
1746#include <sys/kernel.h>
1747
1748#include <sys/cons.h>
1749
1750#include <ddb/ddb.h>
1751
1752static int
1753_vm_object_in_map(vm_map_t map, vm_object_t object, vm_map_entry_t entry)
1754{
1755 vm_map_t tmpm;
1756 vm_map_entry_t tmpe;
1757 vm_object_t obj;
1758 int entcount;
1759
1760 if (map == 0)
1761 return 0;
1762
1763 if (entry == 0) {
1764 tmpe = map->header.next;
1765 entcount = map->nentries;
1766 while (entcount-- && (tmpe != &map->header)) {
1767 if (_vm_object_in_map(map, object, tmpe)) {
1768 return 1;
1769 }
1770 tmpe = tmpe->next;
1771 }
1772 } else if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) {
1773 tmpm = entry->object.sub_map;
1774 tmpe = tmpm->header.next;
1775 entcount = tmpm->nentries;
1776 while (entcount-- && tmpe != &tmpm->header) {
1777 if (_vm_object_in_map(tmpm, object, tmpe)) {
1778 return 1;
1779 }
1780 tmpe = tmpe->next;
1781 }
1782 } else if ((obj = entry->object.vm_object) != NULL) {
1783 for (; obj; obj = obj->backing_object)
1784 if (obj == object) {
1785 return 1;
1786 }
1787 }
1788 return 0;
1789}
1790
1791static int
1792vm_object_in_map(vm_object_t object)
1793{
1794 struct proc *p;
1795
1796 /* sx_slock(&allproc_lock); */
1797 LIST_FOREACH(p, &allproc, p_list) {
1798 if (!p->p_vmspace /* || (p->p_flag & (P_SYSTEM|P_WEXIT)) */)
1799 continue;
1800 if (_vm_object_in_map(&p->p_vmspace->vm_map, object, 0)) {
1801 /* sx_sunlock(&allproc_lock); */
1802 return 1;
1803 }
1804 }
1805 /* sx_sunlock(&allproc_lock); */
1806 if (_vm_object_in_map(kernel_map, object, 0))
1807 return 1;
1808 if (_vm_object_in_map(kmem_map, object, 0))
1809 return 1;
1810 if (_vm_object_in_map(pager_map, object, 0))
1811 return 1;
1812 if (_vm_object_in_map(buffer_map, object, 0))
1813 return 1;
1814 return 0;
1815}
1816
1817DB_SHOW_COMMAND(vmochk, vm_object_check)
1818{
1819 vm_object_t object;
1820
1821 /*
1822 * make sure that internal objs are in a map somewhere
1823 * and none have zero ref counts.
1824 */
1825 TAILQ_FOREACH(object, &vm_object_list, object_list) {
1826 if (object->handle == NULL &&
1827 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) {
1828 if (object->ref_count == 0) {
1829 db_printf("vmochk: internal obj has zero ref count: %ld\n",
1830 (long)object->size);
1831 }
1832 if (!vm_object_in_map(object)) {
1833 db_printf(
1834 "vmochk: internal obj is not in a map: "
1835 "ref: %d, size: %lu: 0x%lx, backing_object: %p\n",
1836 object->ref_count, (u_long)object->size,
1837 (u_long)object->size,
1838 (void *)object->backing_object);
1839 }
1840 }
1841 }
1842}
1843
1844/*
1845 * vm_object_print: [ debug ]
1846 */
1847DB_SHOW_COMMAND(object, vm_object_print_static)
1848{
1849 /* XXX convert args. */
1850 vm_object_t object = (vm_object_t)addr;
1851 boolean_t full = have_addr;
1852
1853 vm_page_t p;
1854
1855 /* XXX count is an (unused) arg. Avoid shadowing it. */
1856#define count was_count
1857
1858 int count;
1859
1860 if (object == NULL)
1861 return;
1862
1863 db_iprintf(
1864 "Object %p: type=%d, size=0x%lx, res=%d, ref=%d, flags=0x%x\n",
1865 object, (int)object->type, (u_long)object->size,
1866 object->resident_page_count, object->ref_count, object->flags);
1867 /*
1868 * XXX no %qd in kernel. Truncate object->backing_object_offset.
1869 */
1870 db_iprintf(" sref=%d, backing_object(%d)=(%p)+0x%lx\n",
1871 object->shadow_count,
1872 object->backing_object ? object->backing_object->ref_count : 0,
1873 object->backing_object, (long)object->backing_object_offset);
1874
1875 if (!full)
1876 return;
1877
1878 db_indent += 2;
1879 count = 0;
1880 TAILQ_FOREACH(p, &object->memq, listq) {
1881 if (count == 0)
1882 db_iprintf("memory:=");
1883 else if (count == 6) {
1884 db_printf("\n");
1885 db_iprintf(" ...");
1886 count = 0;
1887 } else
1888 db_printf(",");
1889 count++;
1890
1891 db_printf("(off=0x%lx,page=0x%lx)",
1892 (u_long) p->pindex, (u_long) VM_PAGE_TO_PHYS(p));
1893 }
1894 if (count != 0)
1895 db_printf("\n");
1896 db_indent -= 2;
1897}
1898
1899/* XXX. */
1900#undef count
1901
1902/* XXX need this non-static entry for calling from vm_map_print. */
1903void
1904vm_object_print(
1905 /* db_expr_t */ long addr,
1906 boolean_t have_addr,
1907 /* db_expr_t */ long count,
1908 char *modif)
1909{
1910 vm_object_print_static(addr, have_addr, count, modif);
1911}
1912
1913DB_SHOW_COMMAND(vmopag, vm_object_print_pages)
1914{
1915 vm_object_t object;
1916 int nl = 0;
1917 int c;
1918
1919 TAILQ_FOREACH(object, &vm_object_list, object_list) {
1920 vm_pindex_t idx, fidx;
1921 vm_pindex_t osize;
1922 vm_offset_t pa = -1, padiff;
1923 int rcount;
1924 vm_page_t m;
1925
1926 db_printf("new object: %p\n", (void *)object);
1927 if (nl > 18) {
1928 c = cngetc();
1929 if (c != ' ')
1930 return;
1931 nl = 0;
1932 }
1933 nl++;
1934 rcount = 0;
1935 fidx = 0;
1936 osize = object->size;
1937 if (osize > 128)
1938 osize = 128;
1939 for (idx = 0; idx < osize; idx++) {
1940 m = vm_page_lookup(object, idx);
1941 if (m == NULL) {
1942 if (rcount) {
1943 db_printf(" index(%ld)run(%d)pa(0x%lx)\n",
1944 (long)fidx, rcount, (long)pa);
1945 if (nl > 18) {
1946 c = cngetc();
1947 if (c != ' ')
1948 return;
1949 nl = 0;
1950 }
1951 nl++;
1952 rcount = 0;
1953 }
1954 continue;
1955 }
1956
1957
1958 if (rcount &&
1959 (VM_PAGE_TO_PHYS(m) == pa + rcount * PAGE_SIZE)) {
1960 ++rcount;
1961 continue;
1962 }
1963 if (rcount) {
1964 padiff = pa + rcount * PAGE_SIZE - VM_PAGE_TO_PHYS(m);
1965 padiff >>= PAGE_SHIFT;
1966 padiff &= PQ_L2_MASK;
1967 if (padiff == 0) {
1968 pa = VM_PAGE_TO_PHYS(m) - rcount * PAGE_SIZE;
1969 ++rcount;
1970 continue;
1971 }
1972 db_printf(" index(%ld)run(%d)pa(0x%lx)",
1973 (long)fidx, rcount, (long)pa);
1974 db_printf("pd(%ld)\n", (long)padiff);
1975 if (nl > 18) {
1976 c = cngetc();
1977 if (c != ' ')
1978 return;
1979 nl = 0;
1980 }
1981 nl++;
1982 }
1983 fidx = idx;
1984 pa = VM_PAGE_TO_PHYS(m);
1985 rcount = 1;
1986 }
1987 if (rcount) {
1988 db_printf(" index(%ld)run(%d)pa(0x%lx)\n",
1989 (long)fidx, rcount, (long)pa);
1990 if (nl > 18) {
1991 c = cngetc();
1992 if (c != ' ')
1993 return;
1994 nl = 0;
1995 }
1996 nl++;
1997 }
1998 }
1999}
2000#endif /* DDB */
| 263}
264
265void
266vm_object_set_flag(vm_object_t object, u_short bits)
267{
268 GIANT_REQUIRED;
269 object->flags |= bits;
270}
271
272void
273vm_object_clear_flag(vm_object_t object, u_short bits)
274{
275 GIANT_REQUIRED;
276 object->flags &= ~bits;
277}
278
279void
280vm_object_pip_add(vm_object_t object, short i)
281{
282 GIANT_REQUIRED;
283 object->paging_in_progress += i;
284}
285
286void
287vm_object_pip_subtract(vm_object_t object, short i)
288{
289 GIANT_REQUIRED;
290 object->paging_in_progress -= i;
291}
292
293void
294vm_object_pip_wakeup(vm_object_t object)
295{
296 GIANT_REQUIRED;
297 object->paging_in_progress--;
298 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
299 vm_object_clear_flag(object, OBJ_PIPWNT);
300 wakeup(object);
301 }
302}
303
304void
305vm_object_pip_wakeupn(vm_object_t object, short i)
306{
307 GIANT_REQUIRED;
308 if (i)
309 object->paging_in_progress -= i;
310 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
311 vm_object_clear_flag(object, OBJ_PIPWNT);
312 wakeup(object);
313 }
314}
315
316void
317vm_object_pip_sleep(vm_object_t object, char *waitid)
318{
319 GIANT_REQUIRED;
320 if (object->paging_in_progress) {
321 int s = splvm();
322 if (object->paging_in_progress) {
323 vm_object_set_flag(object, OBJ_PIPWNT);
324 tsleep(object, PVM, waitid, 0);
325 }
326 splx(s);
327 }
328}
329
330void
331vm_object_pip_wait(vm_object_t object, char *waitid)
332{
333 GIANT_REQUIRED;
334 while (object->paging_in_progress)
335 vm_object_pip_sleep(object, waitid);
336}
337
338/*
339 * vm_object_allocate:
340 *
341 * Returns a new object with the given size.
342 */
343vm_object_t
344vm_object_allocate(objtype_t type, vm_size_t size)
345{
346 vm_object_t result;
347
348 GIANT_REQUIRED;
349
350 result = (vm_object_t) zalloc(obj_zone);
351 _vm_object_allocate(type, size, result);
352
353 return (result);
354}
355
356
357/*
358 * vm_object_reference:
359 *
360 * Gets another reference to the given object.
361 */
362void
363vm_object_reference(vm_object_t object)
364{
365 GIANT_REQUIRED;
366
367 if (object == NULL)
368 return;
369
370#if 0
371 /* object can be re-referenced during final cleaning */
372 KASSERT(!(object->flags & OBJ_DEAD),
373 ("vm_object_reference: attempting to reference dead obj"));
374#endif
375
376 object->ref_count++;
377 if (object->type == OBJT_VNODE) {
378 while (vget((struct vnode *) object->handle, LK_RETRY|LK_NOOBJ, curthread)) {
379 printf("vm_object_reference: delay in getting object\n");
380 }
381 }
382}
383
384/*
385 * handle deallocating a object of type OBJT_VNODE
386 */
387void
388vm_object_vndeallocate(vm_object_t object)
389{
390 struct vnode *vp = (struct vnode *) object->handle;
391
392 GIANT_REQUIRED;
393 KASSERT(object->type == OBJT_VNODE,
394 ("vm_object_vndeallocate: not a vnode object"));
395 KASSERT(vp != NULL, ("vm_object_vndeallocate: missing vp"));
396#ifdef INVARIANTS
397 if (object->ref_count == 0) {
398 vprint("vm_object_vndeallocate", vp);
399 panic("vm_object_vndeallocate: bad object reference count");
400 }
401#endif
402
403 object->ref_count--;
404 if (object->ref_count == 0) {
405 vp->v_flag &= ~VTEXT;
406 vm_object_clear_flag(object, OBJ_OPT);
407 }
408 /*
409 * vrele may need a vop lock
410 */
411 vrele(vp);
412}
413
414/*
415 * vm_object_deallocate:
416 *
417 * Release a reference to the specified object,
418 * gained either through a vm_object_allocate
419 * or a vm_object_reference call. When all references
420 * are gone, storage associated with this object
421 * may be relinquished.
422 *
423 * No object may be locked.
424 */
425void
426vm_object_deallocate(vm_object_t object)
427{
428 vm_object_t temp;
429
430 GIANT_REQUIRED;
431
432 while (object != NULL) {
433
434 if (object->type == OBJT_VNODE) {
435 vm_object_vndeallocate(object);
436 return;
437 }
438
439 KASSERT(object->ref_count != 0,
440 ("vm_object_deallocate: object deallocated too many times: %d", object->type));
441
442 /*
443 * If the reference count goes to 0 we start calling
444 * vm_object_terminate() on the object chain.
445 * A ref count of 1 may be a special case depending on the
446 * shadow count being 0 or 1.
447 */
448 object->ref_count--;
449 if (object->ref_count > 1) {
450 return;
451 } else if (object->ref_count == 1) {
452 if (object->shadow_count == 0) {
453 vm_object_set_flag(object, OBJ_ONEMAPPING);
454 } else if ((object->shadow_count == 1) &&
455 (object->handle == NULL) &&
456 (object->type == OBJT_DEFAULT ||
457 object->type == OBJT_SWAP)) {
458 vm_object_t robject;
459
460 robject = TAILQ_FIRST(&object->shadow_head);
461 KASSERT(robject != NULL,
462 ("vm_object_deallocate: ref_count: %d, shadow_count: %d",
463 object->ref_count,
464 object->shadow_count));
465 if ((robject->handle == NULL) &&
466 (robject->type == OBJT_DEFAULT ||
467 robject->type == OBJT_SWAP)) {
468
469 robject->ref_count++;
470
471 while (
472 robject->paging_in_progress ||
473 object->paging_in_progress
474 ) {
475 vm_object_pip_sleep(robject, "objde1");
476 vm_object_pip_sleep(object, "objde2");
477 }
478
479 if (robject->ref_count == 1) {
480 robject->ref_count--;
481 object = robject;
482 goto doterm;
483 }
484
485 object = robject;
486 vm_object_collapse(object);
487 continue;
488 }
489 }
490
491 return;
492
493 }
494
495doterm:
496
497 temp = object->backing_object;
498 if (temp) {
499 TAILQ_REMOVE(&temp->shadow_head, object, shadow_list);
500 temp->shadow_count--;
501 if (temp->ref_count == 0)
502 vm_object_clear_flag(temp, OBJ_OPT);
503 temp->generation++;
504 object->backing_object = NULL;
505 }
506 /*
507 * Don't double-terminate, we could be in a termination
508 * recursion due to the terminate having to sync data
509 * to disk.
510 */
511 if ((object->flags & OBJ_DEAD) == 0)
512 vm_object_terminate(object);
513 object = temp;
514 }
515}
516
517/*
518 * vm_object_terminate actually destroys the specified object, freeing
519 * up all previously used resources.
520 *
521 * The object must be locked.
522 * This routine may block.
523 */
524void
525vm_object_terminate(vm_object_t object)
526{
527 vm_page_t p;
528 int s;
529
530 GIANT_REQUIRED;
531
532 /*
533 * Make sure no one uses us.
534 */
535 vm_object_set_flag(object, OBJ_DEAD);
536
537 /*
538 * wait for the pageout daemon to be done with the object
539 */
540 vm_object_pip_wait(object, "objtrm");
541
542 KASSERT(!object->paging_in_progress,
543 ("vm_object_terminate: pageout in progress"));
544
545 /*
546 * Clean and free the pages, as appropriate. All references to the
547 * object are gone, so we don't need to lock it.
548 */
549 if (object->type == OBJT_VNODE) {
550 struct vnode *vp;
551
552 /*
553 * Freeze optimized copies.
554 */
555 vm_freeze_copyopts(object, 0, object->size);
556
557 /*
558 * Clean pages and flush buffers.
559 */
560 vm_object_page_clean(object, 0, 0, OBJPC_SYNC);
561
562 vp = (struct vnode *) object->handle;
563 vinvalbuf(vp, V_SAVE, NOCRED, NULL, 0, 0);
564 }
565
566 KASSERT(object->ref_count == 0,
567 ("vm_object_terminate: object with references, ref_count=%d",
568 object->ref_count));
569
570 /*
571 * Now free any remaining pages. For internal objects, this also
572 * removes them from paging queues. Don't free wired pages, just
573 * remove them from the object.
574 */
575 s = splvm();
576 while ((p = TAILQ_FIRST(&object->memq)) != NULL) {
577 KASSERT(!p->busy && (p->flags & PG_BUSY) == 0,
578 ("vm_object_terminate: freeing busy page %p "
579 "p->busy = %d, p->flags %x\n", p, p->busy, p->flags));
580 if (p->wire_count == 0) {
581 vm_page_busy(p);
582 vm_page_free(p);
583 cnt.v_pfree++;
584 } else {
585 vm_page_busy(p);
586 vm_page_remove(p);
587 }
588 }
589 splx(s);
590
591 /*
592 * Let the pager know object is dead.
593 */
594 vm_pager_deallocate(object);
595
596 /*
597 * Remove the object from the global object list.
598 */
599 mtx_lock(&vm_object_list_mtx);
600 TAILQ_REMOVE(&vm_object_list, object, object_list);
601 mtx_unlock(&vm_object_list_mtx);
602
603 wakeup(object);
604
605 /*
606 * Free the space for the object.
607 */
608 zfree(obj_zone, object);
609}
610
611/*
612 * vm_object_page_clean
613 *
614 * Clean all dirty pages in the specified range of object. Leaves page
615 * on whatever queue it is currently on. If NOSYNC is set then do not
616 * write out pages with PG_NOSYNC set (originally comes from MAP_NOSYNC),
617 * leaving the object dirty.
618 *
619 * Odd semantics: if start == end, we clean everything.
620 *
621 * The object must be locked.
622 */
623void
624vm_object_page_clean(vm_object_t object, vm_pindex_t start, vm_pindex_t end, int flags)
625{
626 vm_page_t p, np;
627 vm_offset_t tstart, tend;
628 vm_pindex_t pi;
629 struct vnode *vp;
630 int clearobjflags;
631 int pagerflags;
632 int curgeneration;
633
634 GIANT_REQUIRED;
635
636 if (object->type != OBJT_VNODE ||
637 (object->flags & OBJ_MIGHTBEDIRTY) == 0)
638 return;
639
640 pagerflags = (flags & (OBJPC_SYNC | OBJPC_INVAL)) ? VM_PAGER_PUT_SYNC : 0;
641 pagerflags |= (flags & OBJPC_INVAL) ? VM_PAGER_PUT_INVAL : 0;
642
643 vp = object->handle;
644
645 vm_object_set_flag(object, OBJ_CLEANING);
646
647 tstart = start;
648 if (end == 0) {
649 tend = object->size;
650 } else {
651 tend = end;
652 }
653
654 /*
655 * If the caller is smart and only msync()s a range he knows is
656 * dirty, we may be able to avoid an object scan. This results in
657 * a phenominal improvement in performance. We cannot do this
658 * as a matter of course because the object may be huge - e.g.
659 * the size might be in the gigabytes or terrabytes.
660 */
661 if (msync_flush_flags & MSYNC_FLUSH_HARDSEQ) {
662 vm_offset_t tscan;
663 int scanlimit;
664 int scanreset;
665
666 scanreset = object->resident_page_count / EASY_SCAN_FACTOR;
667 if (scanreset < 16)
668 scanreset = 16;
669
670 scanlimit = scanreset;
671 tscan = tstart;
672 while (tscan < tend) {
673 curgeneration = object->generation;
674 p = vm_page_lookup(object, tscan);
675 if (p == NULL || p->valid == 0 ||
676 (p->queue - p->pc) == PQ_CACHE) {
677 if (--scanlimit == 0)
678 break;
679 ++tscan;
680 continue;
681 }
682 vm_page_test_dirty(p);
683 if ((p->dirty & p->valid) == 0) {
684 if (--scanlimit == 0)
685 break;
686 ++tscan;
687 continue;
688 }
689 /*
690 * If we have been asked to skip nosync pages and
691 * this is a nosync page, we can't continue.
692 */
693 if ((flags & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) {
694 if (--scanlimit == 0)
695 break;
696 ++tscan;
697 continue;
698 }
699 scanlimit = scanreset;
700
701 /*
702 * This returns 0 if it was unable to busy the first
703 * page (i.e. had to sleep).
704 */
705 tscan += vm_object_page_collect_flush(object, p, curgeneration, pagerflags);
706 }
707
708 /*
709 * If everything was dirty and we flushed it successfully,
710 * and the requested range is not the entire object, we
711 * don't have to mess with CLEANCHK or MIGHTBEDIRTY and can
712 * return immediately.
713 */
714 if (tscan >= tend && (tstart || tend < object->size)) {
715 vm_object_clear_flag(object, OBJ_CLEANING);
716 return;
717 }
718 }
719
720 /*
721 * Generally set CLEANCHK interlock and make the page read-only so
722 * we can then clear the object flags.
723 *
724 * However, if this is a nosync mmap then the object is likely to
725 * stay dirty so do not mess with the page and do not clear the
726 * object flags.
727 */
728 clearobjflags = 1;
729
730 TAILQ_FOREACH(p, &object->memq, listq) {
731 vm_page_flag_set(p, PG_CLEANCHK);
732 if ((flags & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC))
733 clearobjflags = 0;
734 else
735 vm_page_protect(p, VM_PROT_READ);
736 }
737
738 if (clearobjflags && (tstart == 0) && (tend == object->size)) {
739 struct vnode *vp;
740
741 vm_object_clear_flag(object, OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY);
742 if (object->type == OBJT_VNODE &&
743 (vp = (struct vnode *)object->handle) != NULL) {
744 if (vp->v_flag & VOBJDIRTY) {
745 mtx_lock(&vp->v_interlock);
746 vp->v_flag &= ~VOBJDIRTY;
747 mtx_unlock(&vp->v_interlock);
748 }
749 }
750 }
751
752rescan:
753 curgeneration = object->generation;
754
755 for (p = TAILQ_FIRST(&object->memq); p; p = np) {
756 int n;
757
758 np = TAILQ_NEXT(p, listq);
759
760again:
761 pi = p->pindex;
762 if (((p->flags & PG_CLEANCHK) == 0) ||
763 (pi < tstart) || (pi >= tend) ||
764 (p->valid == 0) ||
765 ((p->queue - p->pc) == PQ_CACHE)) {
766 vm_page_flag_clear(p, PG_CLEANCHK);
767 continue;
768 }
769
770 vm_page_test_dirty(p);
771 if ((p->dirty & p->valid) == 0) {
772 vm_page_flag_clear(p, PG_CLEANCHK);
773 continue;
774 }
775
776 /*
777 * If we have been asked to skip nosync pages and this is a
778 * nosync page, skip it. Note that the object flags were
779 * not cleared in this case so we do not have to set them.
780 */
781 if ((flags & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) {
782 vm_page_flag_clear(p, PG_CLEANCHK);
783 continue;
784 }
785
786 n = vm_object_page_collect_flush(object, p,
787 curgeneration, pagerflags);
788 if (n == 0)
789 goto rescan;
790
791 if (object->generation != curgeneration)
792 goto rescan;
793
794 /*
795 * Try to optimize the next page. If we can't we pick up
796 * our (random) scan where we left off.
797 */
798 if (msync_flush_flags & MSYNC_FLUSH_SOFTSEQ) {
799 if ((p = vm_page_lookup(object, pi + n)) != NULL)
800 goto again;
801 }
802 }
803
804#if 0
805 VOP_FSYNC(vp, NULL, (pagerflags & VM_PAGER_PUT_SYNC)?MNT_WAIT:0, curproc);
806#endif
807
808 vm_object_clear_flag(object, OBJ_CLEANING);
809 return;
810}
811
812static int
813vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int curgeneration, int pagerflags)
814{
815 int runlen;
816 int s;
817 int maxf;
818 int chkb;
819 int maxb;
820 int i;
821 vm_pindex_t pi;
822 vm_page_t maf[vm_pageout_page_count];
823 vm_page_t mab[vm_pageout_page_count];
824 vm_page_t ma[vm_pageout_page_count];
825
826 s = splvm();
827 pi = p->pindex;
828 while (vm_page_sleep_busy(p, TRUE, "vpcwai")) {
829 if (object->generation != curgeneration) {
830 splx(s);
831 return(0);
832 }
833 }
834
835 maxf = 0;
836 for(i = 1; i < vm_pageout_page_count; i++) {
837 vm_page_t tp;
838
839 if ((tp = vm_page_lookup(object, pi + i)) != NULL) {
840 if ((tp->flags & PG_BUSY) ||
841 (tp->flags & PG_CLEANCHK) == 0 ||
842 (tp->busy != 0))
843 break;
844 if((tp->queue - tp->pc) == PQ_CACHE) {
845 vm_page_flag_clear(tp, PG_CLEANCHK);
846 break;
847 }
848 vm_page_test_dirty(tp);
849 if ((tp->dirty & tp->valid) == 0) {
850 vm_page_flag_clear(tp, PG_CLEANCHK);
851 break;
852 }
853 maf[ i - 1 ] = tp;
854 maxf++;
855 continue;
856 }
857 break;
858 }
859
860 maxb = 0;
861 chkb = vm_pageout_page_count - maxf;
862 if (chkb) {
863 for(i = 1; i < chkb;i++) {
864 vm_page_t tp;
865
866 if ((tp = vm_page_lookup(object, pi - i)) != NULL) {
867 if ((tp->flags & PG_BUSY) ||
868 (tp->flags & PG_CLEANCHK) == 0 ||
869 (tp->busy != 0))
870 break;
871 if ((tp->queue - tp->pc) == PQ_CACHE) {
872 vm_page_flag_clear(tp, PG_CLEANCHK);
873 break;
874 }
875 vm_page_test_dirty(tp);
876 if ((tp->dirty & tp->valid) == 0) {
877 vm_page_flag_clear(tp, PG_CLEANCHK);
878 break;
879 }
880 mab[ i - 1 ] = tp;
881 maxb++;
882 continue;
883 }
884 break;
885 }
886 }
887
888 for(i = 0; i < maxb; i++) {
889 int index = (maxb - i) - 1;
890 ma[index] = mab[i];
891 vm_page_flag_clear(ma[index], PG_CLEANCHK);
892 }
893 vm_page_flag_clear(p, PG_CLEANCHK);
894 ma[maxb] = p;
895 for(i = 0; i < maxf; i++) {
896 int index = (maxb + i) + 1;
897 ma[index] = maf[i];
898 vm_page_flag_clear(ma[index], PG_CLEANCHK);
899 }
900 runlen = maxb + maxf + 1;
901
902 splx(s);
903 vm_pageout_flush(ma, runlen, pagerflags);
904 for (i = 0; i < runlen; i++) {
905 if (ma[i]->valid & ma[i]->dirty) {
906 vm_page_protect(ma[i], VM_PROT_READ);
907 vm_page_flag_set(ma[i], PG_CLEANCHK);
908
909 /*
910 * maxf will end up being the actual number of pages
911 * we wrote out contiguously, non-inclusive of the
912 * first page. We do not count look-behind pages.
913 */
914 if (i >= maxb + 1 && (maxf > i - maxb - 1))
915 maxf = i - maxb - 1;
916 }
917 }
918 return(maxf + 1);
919}
920
921/*
922 * Same as vm_object_pmap_copy, except range checking really
923 * works, and is meant for small sections of an object.
924 *
925 * This code protects resident pages by making them read-only
926 * and is typically called on a fork or split when a page
927 * is converted to copy-on-write.
928 *
929 * NOTE: If the page is already at VM_PROT_NONE, calling
930 * vm_page_protect will have no effect.
931 */
932void
933vm_object_pmap_copy_1(vm_object_t object, vm_pindex_t start, vm_pindex_t end)
934{
935 vm_pindex_t idx;
936 vm_page_t p;
937
938 GIANT_REQUIRED;
939
940 if (object == NULL || (object->flags & OBJ_WRITEABLE) == 0)
941 return;
942
943 for (idx = start; idx < end; idx++) {
944 p = vm_page_lookup(object, idx);
945 if (p == NULL)
946 continue;
947 vm_page_protect(p, VM_PROT_READ);
948 }
949}
950
951/*
952 * vm_object_pmap_remove:
953 *
954 * Removes all physical pages in the specified
955 * object range from all physical maps.
956 *
957 * The object must *not* be locked.
958 */
959void
960vm_object_pmap_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end)
961{
962 vm_page_t p;
963
964 GIANT_REQUIRED;
965 if (object == NULL)
966 return;
967 TAILQ_FOREACH(p, &object->memq, listq) {
968 if (p->pindex >= start && p->pindex < end)
969 vm_page_protect(p, VM_PROT_NONE);
970 }
971 if ((start == 0) && (object->size == end))
972 vm_object_clear_flag(object, OBJ_WRITEABLE);
973}
974
975/*
976 * vm_object_madvise:
977 *
978 * Implements the madvise function at the object/page level.
979 *
980 * MADV_WILLNEED (any object)
981 *
982 * Activate the specified pages if they are resident.
983 *
984 * MADV_DONTNEED (any object)
985 *
986 * Deactivate the specified pages if they are resident.
987 *
988 * MADV_FREE (OBJT_DEFAULT/OBJT_SWAP objects,
989 * OBJ_ONEMAPPING only)
990 *
991 * Deactivate and clean the specified pages if they are
992 * resident. This permits the process to reuse the pages
993 * without faulting or the kernel to reclaim the pages
994 * without I/O.
995 */
996void
997vm_object_madvise(vm_object_t object, vm_pindex_t pindex, int count, int advise)
998{
999 vm_pindex_t end, tpindex;
1000 vm_object_t tobject;
1001 vm_page_t m;
1002
1003 GIANT_REQUIRED;
1004 if (object == NULL)
1005 return;
1006
1007 end = pindex + count;
1008
1009 /*
1010 * Locate and adjust resident pages
1011 */
1012 for (; pindex < end; pindex += 1) {
1013relookup:
1014 tobject = object;
1015 tpindex = pindex;
1016shadowlookup:
1017 /*
1018 * MADV_FREE only operates on OBJT_DEFAULT or OBJT_SWAP pages
1019 * and those pages must be OBJ_ONEMAPPING.
1020 */
1021 if (advise == MADV_FREE) {
1022 if ((tobject->type != OBJT_DEFAULT &&
1023 tobject->type != OBJT_SWAP) ||
1024 (tobject->flags & OBJ_ONEMAPPING) == 0) {
1025 continue;
1026 }
1027 }
1028
1029 m = vm_page_lookup(tobject, tpindex);
1030
1031 if (m == NULL) {
1032 /*
1033 * There may be swap even if there is no backing page
1034 */
1035 if (advise == MADV_FREE && tobject->type == OBJT_SWAP)
1036 swap_pager_freespace(tobject, tpindex, 1);
1037
1038 /*
1039 * next object
1040 */
1041 tobject = tobject->backing_object;
1042 if (tobject == NULL)
1043 continue;
1044 tpindex += OFF_TO_IDX(tobject->backing_object_offset);
1045 goto shadowlookup;
1046 }
1047
1048 /*
1049 * If the page is busy or not in a normal active state,
1050 * we skip it. If the page is not managed there are no
1051 * page queues to mess with. Things can break if we mess
1052 * with pages in any of the below states.
1053 */
1054 if (
1055 m->hold_count ||
1056 m->wire_count ||
1057 (m->flags & PG_UNMANAGED) ||
1058 m->valid != VM_PAGE_BITS_ALL
1059 ) {
1060 continue;
1061 }
1062
1063 if (vm_page_sleep_busy(m, TRUE, "madvpo"))
1064 goto relookup;
1065
1066 if (advise == MADV_WILLNEED) {
1067 vm_page_activate(m);
1068 } else if (advise == MADV_DONTNEED) {
1069 vm_page_dontneed(m);
1070 } else if (advise == MADV_FREE) {
1071 /*
1072 * Mark the page clean. This will allow the page
1073 * to be freed up by the system. However, such pages
1074 * are often reused quickly by malloc()/free()
1075 * so we do not do anything that would cause
1076 * a page fault if we can help it.
1077 *
1078 * Specifically, we do not try to actually free
1079 * the page now nor do we try to put it in the
1080 * cache (which would cause a page fault on reuse).
1081 *
1082 * But we do make the page is freeable as we
1083 * can without actually taking the step of unmapping
1084 * it.
1085 */
1086 pmap_clear_modify(m);
1087 m->dirty = 0;
1088 m->act_count = 0;
1089 vm_page_dontneed(m);
1090 if (tobject->type == OBJT_SWAP)
1091 swap_pager_freespace(tobject, tpindex, 1);
1092 }
1093 }
1094}
1095
1096/*
1097 * vm_object_shadow:
1098 *
1099 * Create a new object which is backed by the
1100 * specified existing object range. The source
1101 * object reference is deallocated.
1102 *
1103 * The new object and offset into that object
1104 * are returned in the source parameters.
1105 */
1106void
1107vm_object_shadow(
1108 vm_object_t *object, /* IN/OUT */
1109 vm_ooffset_t *offset, /* IN/OUT */
1110 vm_size_t length)
1111{
1112 vm_object_t source;
1113 vm_object_t result;
1114
1115 GIANT_REQUIRED;
1116 source = *object;
1117
1118 /*
1119 * Don't create the new object if the old object isn't shared.
1120 */
1121 if (source != NULL &&
1122 source->ref_count == 1 &&
1123 source->handle == NULL &&
1124 (source->type == OBJT_DEFAULT ||
1125 source->type == OBJT_SWAP))
1126 return;
1127
1128 /*
1129 * Allocate a new object with the given length
1130 */
1131 result = vm_object_allocate(OBJT_DEFAULT, length);
1132 KASSERT(result != NULL, ("vm_object_shadow: no object for shadowing"));
1133
1134 /*
1135 * The new object shadows the source object, adding a reference to it.
1136 * Our caller changes his reference to point to the new object,
1137 * removing a reference to the source object. Net result: no change
1138 * of reference count.
1139 *
1140 * Try to optimize the result object's page color when shadowing
1141 * in order to maintain page coloring consistency in the combined
1142 * shadowed object.
1143 */
1144 result->backing_object = source;
1145 if (source) {
1146 TAILQ_INSERT_TAIL(&source->shadow_head, result, shadow_list);
1147 source->shadow_count++;
1148 source->generation++;
1149 result->pg_color = (source->pg_color + OFF_TO_IDX(*offset)) & PQ_L2_MASK;
1150 }
1151
1152 /*
1153 * Store the offset into the source object, and fix up the offset into
1154 * the new object.
1155 */
1156 result->backing_object_offset = *offset;
1157
1158 /*
1159 * Return the new things
1160 */
1161 *offset = 0;
1162 *object = result;
1163}
1164
1165#define OBSC_TEST_ALL_SHADOWED 0x0001
1166#define OBSC_COLLAPSE_NOWAIT 0x0002
1167#define OBSC_COLLAPSE_WAIT 0x0004
1168
1169static __inline int
1170vm_object_backing_scan(vm_object_t object, int op)
1171{
1172 int s;
1173 int r = 1;
1174 vm_page_t p;
1175 vm_object_t backing_object;
1176 vm_pindex_t backing_offset_index;
1177
1178 s = splvm();
1179 GIANT_REQUIRED;
1180
1181 backing_object = object->backing_object;
1182 backing_offset_index = OFF_TO_IDX(object->backing_object_offset);
1183
1184 /*
1185 * Initial conditions
1186 */
1187 if (op & OBSC_TEST_ALL_SHADOWED) {
1188 /*
1189 * We do not want to have to test for the existence of
1190 * swap pages in the backing object. XXX but with the
1191 * new swapper this would be pretty easy to do.
1192 *
1193 * XXX what about anonymous MAP_SHARED memory that hasn't
1194 * been ZFOD faulted yet? If we do not test for this, the
1195 * shadow test may succeed! XXX
1196 */
1197 if (backing_object->type != OBJT_DEFAULT) {
1198 splx(s);
1199 return (0);
1200 }
1201 }
1202 if (op & OBSC_COLLAPSE_WAIT) {
1203 vm_object_set_flag(backing_object, OBJ_DEAD);
1204 }
1205
1206 /*
1207 * Our scan
1208 */
1209 p = TAILQ_FIRST(&backing_object->memq);
1210 while (p) {
1211 vm_page_t next = TAILQ_NEXT(p, listq);
1212 vm_pindex_t new_pindex = p->pindex - backing_offset_index;
1213
1214 if (op & OBSC_TEST_ALL_SHADOWED) {
1215 vm_page_t pp;
1216
1217 /*
1218 * Ignore pages outside the parent object's range
1219 * and outside the parent object's mapping of the
1220 * backing object.
1221 *
1222 * note that we do not busy the backing object's
1223 * page.
1224 */
1225 if (
1226 p->pindex < backing_offset_index ||
1227 new_pindex >= object->size
1228 ) {
1229 p = next;
1230 continue;
1231 }
1232
1233 /*
1234 * See if the parent has the page or if the parent's
1235 * object pager has the page. If the parent has the
1236 * page but the page is not valid, the parent's
1237 * object pager must have the page.
1238 *
1239 * If this fails, the parent does not completely shadow
1240 * the object and we might as well give up now.
1241 */
1242
1243 pp = vm_page_lookup(object, new_pindex);
1244 if (
1245 (pp == NULL || pp->valid == 0) &&
1246 !vm_pager_has_page(object, new_pindex, NULL, NULL)
1247 ) {
1248 r = 0;
1249 break;
1250 }
1251 }
1252
1253 /*
1254 * Check for busy page
1255 */
1256 if (op & (OBSC_COLLAPSE_WAIT | OBSC_COLLAPSE_NOWAIT)) {
1257 vm_page_t pp;
1258
1259 if (op & OBSC_COLLAPSE_NOWAIT) {
1260 if (
1261 (p->flags & PG_BUSY) ||
1262 !p->valid ||
1263 p->hold_count ||
1264 p->wire_count ||
1265 p->busy
1266 ) {
1267 p = next;
1268 continue;
1269 }
1270 } else if (op & OBSC_COLLAPSE_WAIT) {
1271 if (vm_page_sleep_busy(p, TRUE, "vmocol")) {
1272 /*
1273 * If we slept, anything could have
1274 * happened. Since the object is
1275 * marked dead, the backing offset
1276 * should not have changed so we
1277 * just restart our scan.
1278 */
1279 p = TAILQ_FIRST(&backing_object->memq);
1280 continue;
1281 }
1282 }
1283
1284 /*
1285 * Busy the page
1286 */
1287 vm_page_busy(p);
1288
1289 KASSERT(
1290 p->object == backing_object,
1291 ("vm_object_qcollapse(): object mismatch")
1292 );
1293
1294 /*
1295 * Destroy any associated swap
1296 */
1297 if (backing_object->type == OBJT_SWAP) {
1298 swap_pager_freespace(
1299 backing_object,
1300 p->pindex,
1301 1
1302 );
1303 }
1304
1305 if (
1306 p->pindex < backing_offset_index ||
1307 new_pindex >= object->size
1308 ) {
1309 /*
1310 * Page is out of the parent object's range, we
1311 * can simply destroy it.
1312 */
1313 vm_page_protect(p, VM_PROT_NONE);
1314 vm_page_free(p);
1315 p = next;
1316 continue;
1317 }
1318
1319 pp = vm_page_lookup(object, new_pindex);
1320 if (
1321 pp != NULL ||
1322 vm_pager_has_page(object, new_pindex, NULL, NULL)
1323 ) {
1324 /*
1325 * page already exists in parent OR swap exists
1326 * for this location in the parent. Destroy
1327 * the original page from the backing object.
1328 *
1329 * Leave the parent's page alone
1330 */
1331 vm_page_protect(p, VM_PROT_NONE);
1332 vm_page_free(p);
1333 p = next;
1334 continue;
1335 }
1336
1337 /*
1338 * Page does not exist in parent, rename the
1339 * page from the backing object to the main object.
1340 *
1341 * If the page was mapped to a process, it can remain
1342 * mapped through the rename.
1343 */
1344 if ((p->queue - p->pc) == PQ_CACHE)
1345 vm_page_deactivate(p);
1346
1347 vm_page_rename(p, object, new_pindex);
1348 /* page automatically made dirty by rename */
1349 }
1350 p = next;
1351 }
1352 splx(s);
1353 return (r);
1354}
1355
1356
1357/*
1358 * this version of collapse allows the operation to occur earlier and
1359 * when paging_in_progress is true for an object... This is not a complete
1360 * operation, but should plug 99.9% of the rest of the leaks.
1361 */
1362static void
1363vm_object_qcollapse(vm_object_t object)
1364{
1365 vm_object_t backing_object = object->backing_object;
1366
1367 GIANT_REQUIRED;
1368
1369 if (backing_object->ref_count != 1)
1370 return;
1371
1372 backing_object->ref_count += 2;
1373
1374 vm_object_backing_scan(object, OBSC_COLLAPSE_NOWAIT);
1375
1376 backing_object->ref_count -= 2;
1377}
1378
1379/*
1380 * vm_object_collapse:
1381 *
1382 * Collapse an object with the object backing it.
1383 * Pages in the backing object are moved into the
1384 * parent, and the backing object is deallocated.
1385 */
1386void
1387vm_object_collapse(vm_object_t object)
1388{
1389 GIANT_REQUIRED;
1390
1391 while (TRUE) {
1392 vm_object_t backing_object;
1393
1394 /*
1395 * Verify that the conditions are right for collapse:
1396 *
1397 * The object exists and the backing object exists.
1398 */
1399 if (object == NULL)
1400 break;
1401
1402 if ((backing_object = object->backing_object) == NULL)
1403 break;
1404
1405 /*
1406 * we check the backing object first, because it is most likely
1407 * not collapsable.
1408 */
1409 if (backing_object->handle != NULL ||
1410 (backing_object->type != OBJT_DEFAULT &&
1411 backing_object->type != OBJT_SWAP) ||
1412 (backing_object->flags & OBJ_DEAD) ||
1413 object->handle != NULL ||
1414 (object->type != OBJT_DEFAULT &&
1415 object->type != OBJT_SWAP) ||
1416 (object->flags & OBJ_DEAD)) {
1417 break;
1418 }
1419
1420 if (
1421 object->paging_in_progress != 0 ||
1422 backing_object->paging_in_progress != 0
1423 ) {
1424 vm_object_qcollapse(object);
1425 break;
1426 }
1427
1428 /*
1429 * We know that we can either collapse the backing object (if
1430 * the parent is the only reference to it) or (perhaps) have
1431 * the parent bypass the object if the parent happens to shadow
1432 * all the resident pages in the entire backing object.
1433 *
1434 * This is ignoring pager-backed pages such as swap pages.
1435 * vm_object_backing_scan fails the shadowing test in this
1436 * case.
1437 */
1438 if (backing_object->ref_count == 1) {
1439 /*
1440 * If there is exactly one reference to the backing
1441 * object, we can collapse it into the parent.
1442 */
1443 vm_object_backing_scan(object, OBSC_COLLAPSE_WAIT);
1444
1445 /*
1446 * Move the pager from backing_object to object.
1447 */
1448 if (backing_object->type == OBJT_SWAP) {
1449 vm_object_pip_add(backing_object, 1);
1450
1451 /*
1452 * scrap the paging_offset junk and do a
1453 * discrete copy. This also removes major
1454 * assumptions about how the swap-pager
1455 * works from where it doesn't belong. The
1456 * new swapper is able to optimize the
1457 * destroy-source case.
1458 */
1459 vm_object_pip_add(object, 1);
1460 swap_pager_copy(
1461 backing_object,
1462 object,
1463 OFF_TO_IDX(object->backing_object_offset), TRUE);
1464 vm_object_pip_wakeup(object);
1465
1466 vm_object_pip_wakeup(backing_object);
1467 }
1468 /*
1469 * Object now shadows whatever backing_object did.
1470 * Note that the reference to
1471 * backing_object->backing_object moves from within
1472 * backing_object to within object.
1473 */
1474 TAILQ_REMOVE(
1475 &object->backing_object->shadow_head,
1476 object,
1477 shadow_list
1478 );
1479 object->backing_object->shadow_count--;
1480 object->backing_object->generation++;
1481 if (backing_object->backing_object) {
1482 TAILQ_REMOVE(
1483 &backing_object->backing_object->shadow_head,
1484 backing_object,
1485 shadow_list
1486 );
1487 backing_object->backing_object->shadow_count--;
1488 backing_object->backing_object->generation++;
1489 }
1490 object->backing_object = backing_object->backing_object;
1491 if (object->backing_object) {
1492 TAILQ_INSERT_TAIL(
1493 &object->backing_object->shadow_head,
1494 object,
1495 shadow_list
1496 );
1497 object->backing_object->shadow_count++;
1498 object->backing_object->generation++;
1499 }
1500
1501 object->backing_object_offset +=
1502 backing_object->backing_object_offset;
1503
1504 /*
1505 * Discard backing_object.
1506 *
1507 * Since the backing object has no pages, no pager left,
1508 * and no object references within it, all that is
1509 * necessary is to dispose of it.
1510 */
1511 KASSERT(backing_object->ref_count == 1, ("backing_object %p was somehow re-referenced during collapse!", backing_object));
1512 KASSERT(TAILQ_FIRST(&backing_object->memq) == NULL, ("backing_object %p somehow has left over pages during collapse!", backing_object));
1513
1514 TAILQ_REMOVE(
1515 &vm_object_list,
1516 backing_object,
1517 object_list
1518 );
1519
1520 zfree(obj_zone, backing_object);
1521
1522 object_collapses++;
1523 } else {
1524 vm_object_t new_backing_object;
1525
1526 /*
1527 * If we do not entirely shadow the backing object,
1528 * there is nothing we can do so we give up.
1529 */
1530 if (vm_object_backing_scan(object, OBSC_TEST_ALL_SHADOWED) == 0) {
1531 break;
1532 }
1533
1534 /*
1535 * Make the parent shadow the next object in the
1536 * chain. Deallocating backing_object will not remove
1537 * it, since its reference count is at least 2.
1538 */
1539 TAILQ_REMOVE(
1540 &backing_object->shadow_head,
1541 object,
1542 shadow_list
1543 );
1544 backing_object->shadow_count--;
1545 backing_object->generation++;
1546
1547 new_backing_object = backing_object->backing_object;
1548 if ((object->backing_object = new_backing_object) != NULL) {
1549 vm_object_reference(new_backing_object);
1550 TAILQ_INSERT_TAIL(
1551 &new_backing_object->shadow_head,
1552 object,
1553 shadow_list
1554 );
1555 new_backing_object->shadow_count++;
1556 new_backing_object->generation++;
1557 object->backing_object_offset +=
1558 backing_object->backing_object_offset;
1559 }
1560
1561 /*
1562 * Drop the reference count on backing_object. Since
1563 * its ref_count was at least 2, it will not vanish;
1564 * so we don't need to call vm_object_deallocate, but
1565 * we do anyway.
1566 */
1567 vm_object_deallocate(backing_object);
1568 object_bypasses++;
1569 }
1570
1571 /*
1572 * Try again with this object's new backing object.
1573 */
1574 }
1575}
1576
1577/*
1578 * vm_object_page_remove: [internal]
1579 *
1580 * Removes all physical pages in the specified
1581 * object range from the object's list of pages.
1582 *
1583 * The object must be locked.
1584 */
1585void
1586vm_object_page_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end, boolean_t clean_only)
1587{
1588 vm_page_t p, next;
1589 unsigned int size;
1590 int all;
1591
1592 GIANT_REQUIRED;
1593
1594 if (object == NULL ||
1595 object->resident_page_count == 0)
1596 return;
1597
1598 all = ((end == 0) && (start == 0));
1599
1600 /*
1601 * Since physically-backed objects do not use managed pages, we can't
1602 * remove pages from the object (we must instead remove the page
1603 * references, and then destroy the object).
1604 */
1605 KASSERT(object->type != OBJT_PHYS, ("attempt to remove pages from a physical object"));
1606
1607 vm_object_pip_add(object, 1);
1608again:
1609 size = end - start;
1610 if (all || size > object->resident_page_count / 4) {
1611 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = next) {
1612 next = TAILQ_NEXT(p, listq);
1613 if (all || ((start <= p->pindex) && (p->pindex < end))) {
1614 if (p->wire_count != 0) {
1615 vm_page_protect(p, VM_PROT_NONE);
1616 if (!clean_only)
1617 p->valid = 0;
1618 continue;
1619 }
1620
1621 /*
1622 * The busy flags are only cleared at
1623 * interrupt -- minimize the spl transitions
1624 */
1625 if (vm_page_sleep_busy(p, TRUE, "vmopar"))
1626 goto again;
1627
1628 if (clean_only && p->valid) {
1629 vm_page_test_dirty(p);
1630 if (p->valid & p->dirty)
1631 continue;
1632 }
1633
1634 vm_page_busy(p);
1635 vm_page_protect(p, VM_PROT_NONE);
1636 vm_page_free(p);
1637 }
1638 }
1639 } else {
1640 while (size > 0) {
1641 if ((p = vm_page_lookup(object, start)) != 0) {
1642
1643 if (p->wire_count != 0) {
1644 vm_page_protect(p, VM_PROT_NONE);
1645 if (!clean_only)
1646 p->valid = 0;
1647 start += 1;
1648 size -= 1;
1649 continue;
1650 }
1651
1652 /*
1653 * The busy flags are only cleared at
1654 * interrupt -- minimize the spl transitions
1655 */
1656 if (vm_page_sleep_busy(p, TRUE, "vmopar"))
1657 goto again;
1658
1659 if (clean_only && p->valid) {
1660 vm_page_test_dirty(p);
1661 if (p->valid & p->dirty) {
1662 start += 1;
1663 size -= 1;
1664 continue;
1665 }
1666 }
1667
1668 vm_page_busy(p);
1669 vm_page_protect(p, VM_PROT_NONE);
1670 vm_page_free(p);
1671 }
1672 start += 1;
1673 size -= 1;
1674 }
1675 }
1676 vm_object_pip_wakeup(object);
1677}
1678
1679/*
1680 * Routine: vm_object_coalesce
1681 * Function: Coalesces two objects backing up adjoining
1682 * regions of memory into a single object.
1683 *
1684 * returns TRUE if objects were combined.
1685 *
1686 * NOTE: Only works at the moment if the second object is NULL -
1687 * if it's not, which object do we lock first?
1688 *
1689 * Parameters:
1690 * prev_object First object to coalesce
1691 * prev_offset Offset into prev_object
1692 * next_object Second object into coalesce
1693 * next_offset Offset into next_object
1694 *
1695 * prev_size Size of reference to prev_object
1696 * next_size Size of reference to next_object
1697 *
1698 * Conditions:
1699 * The object must *not* be locked.
1700 */
1701boolean_t
1702vm_object_coalesce(vm_object_t prev_object, vm_pindex_t prev_pindex, vm_size_t prev_size, vm_size_t next_size)
1703{
1704 vm_pindex_t next_pindex;
1705
1706 GIANT_REQUIRED;
1707
1708 if (prev_object == NULL) {
1709 return (TRUE);
1710 }
1711
1712 if (prev_object->type != OBJT_DEFAULT &&
1713 prev_object->type != OBJT_SWAP) {
1714 return (FALSE);
1715 }
1716
1717 /*
1718 * Try to collapse the object first
1719 */
1720 vm_object_collapse(prev_object);
1721
1722 /*
1723 * Can't coalesce if: . more than one reference . paged out . shadows
1724 * another object . has a copy elsewhere (any of which mean that the
1725 * pages not mapped to prev_entry may be in use anyway)
1726 */
1727 if (prev_object->backing_object != NULL) {
1728 return (FALSE);
1729 }
1730
1731 prev_size >>= PAGE_SHIFT;
1732 next_size >>= PAGE_SHIFT;
1733 next_pindex = prev_pindex + prev_size;
1734
1735 if ((prev_object->ref_count > 1) &&
1736 (prev_object->size != next_pindex)) {
1737 return (FALSE);
1738 }
1739
1740 /*
1741 * Remove any pages that may still be in the object from a previous
1742 * deallocation.
1743 */
1744 if (next_pindex < prev_object->size) {
1745 vm_object_page_remove(prev_object,
1746 next_pindex,
1747 next_pindex + next_size, FALSE);
1748 if (prev_object->type == OBJT_SWAP)
1749 swap_pager_freespace(prev_object,
1750 next_pindex, next_size);
1751 }
1752
1753 /*
1754 * Extend the object if necessary.
1755 */
1756 if (next_pindex + next_size > prev_object->size)
1757 prev_object->size = next_pindex + next_size;
1758
1759 return (TRUE);
1760}
1761
1762void
1763vm_object_set_writeable_dirty(vm_object_t object)
1764{
1765 struct vnode *vp;
1766
1767 vm_object_set_flag(object, OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY);
1768 if (object->type == OBJT_VNODE &&
1769 (vp = (struct vnode *)object->handle) != NULL) {
1770 if ((vp->v_flag & VOBJDIRTY) == 0) {
1771 mtx_lock(&vp->v_interlock);
1772 vp->v_flag |= VOBJDIRTY;
1773 mtx_unlock(&vp->v_interlock);
1774 }
1775 }
1776}
1777
1778#include "opt_ddb.h"
1779#ifdef DDB
1780#include <sys/kernel.h>
1781
1782#include <sys/cons.h>
1783
1784#include <ddb/ddb.h>
1785
1786static int
1787_vm_object_in_map(vm_map_t map, vm_object_t object, vm_map_entry_t entry)
1788{
1789 vm_map_t tmpm;
1790 vm_map_entry_t tmpe;
1791 vm_object_t obj;
1792 int entcount;
1793
1794 if (map == 0)
1795 return 0;
1796
1797 if (entry == 0) {
1798 tmpe = map->header.next;
1799 entcount = map->nentries;
1800 while (entcount-- && (tmpe != &map->header)) {
1801 if (_vm_object_in_map(map, object, tmpe)) {
1802 return 1;
1803 }
1804 tmpe = tmpe->next;
1805 }
1806 } else if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) {
1807 tmpm = entry->object.sub_map;
1808 tmpe = tmpm->header.next;
1809 entcount = tmpm->nentries;
1810 while (entcount-- && tmpe != &tmpm->header) {
1811 if (_vm_object_in_map(tmpm, object, tmpe)) {
1812 return 1;
1813 }
1814 tmpe = tmpe->next;
1815 }
1816 } else if ((obj = entry->object.vm_object) != NULL) {
1817 for (; obj; obj = obj->backing_object)
1818 if (obj == object) {
1819 return 1;
1820 }
1821 }
1822 return 0;
1823}
1824
1825static int
1826vm_object_in_map(vm_object_t object)
1827{
1828 struct proc *p;
1829
1830 /* sx_slock(&allproc_lock); */
1831 LIST_FOREACH(p, &allproc, p_list) {
1832 if (!p->p_vmspace /* || (p->p_flag & (P_SYSTEM|P_WEXIT)) */)
1833 continue;
1834 if (_vm_object_in_map(&p->p_vmspace->vm_map, object, 0)) {
1835 /* sx_sunlock(&allproc_lock); */
1836 return 1;
1837 }
1838 }
1839 /* sx_sunlock(&allproc_lock); */
1840 if (_vm_object_in_map(kernel_map, object, 0))
1841 return 1;
1842 if (_vm_object_in_map(kmem_map, object, 0))
1843 return 1;
1844 if (_vm_object_in_map(pager_map, object, 0))
1845 return 1;
1846 if (_vm_object_in_map(buffer_map, object, 0))
1847 return 1;
1848 return 0;
1849}
1850
1851DB_SHOW_COMMAND(vmochk, vm_object_check)
1852{
1853 vm_object_t object;
1854
1855 /*
1856 * make sure that internal objs are in a map somewhere
1857 * and none have zero ref counts.
1858 */
1859 TAILQ_FOREACH(object, &vm_object_list, object_list) {
1860 if (object->handle == NULL &&
1861 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) {
1862 if (object->ref_count == 0) {
1863 db_printf("vmochk: internal obj has zero ref count: %ld\n",
1864 (long)object->size);
1865 }
1866 if (!vm_object_in_map(object)) {
1867 db_printf(
1868 "vmochk: internal obj is not in a map: "
1869 "ref: %d, size: %lu: 0x%lx, backing_object: %p\n",
1870 object->ref_count, (u_long)object->size,
1871 (u_long)object->size,
1872 (void *)object->backing_object);
1873 }
1874 }
1875 }
1876}
1877
1878/*
1879 * vm_object_print: [ debug ]
1880 */
1881DB_SHOW_COMMAND(object, vm_object_print_static)
1882{
1883 /* XXX convert args. */
1884 vm_object_t object = (vm_object_t)addr;
1885 boolean_t full = have_addr;
1886
1887 vm_page_t p;
1888
1889 /* XXX count is an (unused) arg. Avoid shadowing it. */
1890#define count was_count
1891
1892 int count;
1893
1894 if (object == NULL)
1895 return;
1896
1897 db_iprintf(
1898 "Object %p: type=%d, size=0x%lx, res=%d, ref=%d, flags=0x%x\n",
1899 object, (int)object->type, (u_long)object->size,
1900 object->resident_page_count, object->ref_count, object->flags);
1901 /*
1902 * XXX no %qd in kernel. Truncate object->backing_object_offset.
1903 */
1904 db_iprintf(" sref=%d, backing_object(%d)=(%p)+0x%lx\n",
1905 object->shadow_count,
1906 object->backing_object ? object->backing_object->ref_count : 0,
1907 object->backing_object, (long)object->backing_object_offset);
1908
1909 if (!full)
1910 return;
1911
1912 db_indent += 2;
1913 count = 0;
1914 TAILQ_FOREACH(p, &object->memq, listq) {
1915 if (count == 0)
1916 db_iprintf("memory:=");
1917 else if (count == 6) {
1918 db_printf("\n");
1919 db_iprintf(" ...");
1920 count = 0;
1921 } else
1922 db_printf(",");
1923 count++;
1924
1925 db_printf("(off=0x%lx,page=0x%lx)",
1926 (u_long) p->pindex, (u_long) VM_PAGE_TO_PHYS(p));
1927 }
1928 if (count != 0)
1929 db_printf("\n");
1930 db_indent -= 2;
1931}
1932
1933/* XXX. */
1934#undef count
1935
1936/* XXX need this non-static entry for calling from vm_map_print. */
1937void
1938vm_object_print(
1939 /* db_expr_t */ long addr,
1940 boolean_t have_addr,
1941 /* db_expr_t */ long count,
1942 char *modif)
1943{
1944 vm_object_print_static(addr, have_addr, count, modif);
1945}
1946
1947DB_SHOW_COMMAND(vmopag, vm_object_print_pages)
1948{
1949 vm_object_t object;
1950 int nl = 0;
1951 int c;
1952
1953 TAILQ_FOREACH(object, &vm_object_list, object_list) {
1954 vm_pindex_t idx, fidx;
1955 vm_pindex_t osize;
1956 vm_offset_t pa = -1, padiff;
1957 int rcount;
1958 vm_page_t m;
1959
1960 db_printf("new object: %p\n", (void *)object);
1961 if (nl > 18) {
1962 c = cngetc();
1963 if (c != ' ')
1964 return;
1965 nl = 0;
1966 }
1967 nl++;
1968 rcount = 0;
1969 fidx = 0;
1970 osize = object->size;
1971 if (osize > 128)
1972 osize = 128;
1973 for (idx = 0; idx < osize; idx++) {
1974 m = vm_page_lookup(object, idx);
1975 if (m == NULL) {
1976 if (rcount) {
1977 db_printf(" index(%ld)run(%d)pa(0x%lx)\n",
1978 (long)fidx, rcount, (long)pa);
1979 if (nl > 18) {
1980 c = cngetc();
1981 if (c != ' ')
1982 return;
1983 nl = 0;
1984 }
1985 nl++;
1986 rcount = 0;
1987 }
1988 continue;
1989 }
1990
1991
1992 if (rcount &&
1993 (VM_PAGE_TO_PHYS(m) == pa + rcount * PAGE_SIZE)) {
1994 ++rcount;
1995 continue;
1996 }
1997 if (rcount) {
1998 padiff = pa + rcount * PAGE_SIZE - VM_PAGE_TO_PHYS(m);
1999 padiff >>= PAGE_SHIFT;
2000 padiff &= PQ_L2_MASK;
2001 if (padiff == 0) {
2002 pa = VM_PAGE_TO_PHYS(m) - rcount * PAGE_SIZE;
2003 ++rcount;
2004 continue;
2005 }
2006 db_printf(" index(%ld)run(%d)pa(0x%lx)",
2007 (long)fidx, rcount, (long)pa);
2008 db_printf("pd(%ld)\n", (long)padiff);
2009 if (nl > 18) {
2010 c = cngetc();
2011 if (c != ' ')
2012 return;
2013 nl = 0;
2014 }
2015 nl++;
2016 }
2017 fidx = idx;
2018 pa = VM_PAGE_TO_PHYS(m);
2019 rcount = 1;
2020 }
2021 if (rcount) {
2022 db_printf(" index(%ld)run(%d)pa(0x%lx)\n",
2023 (long)fidx, rcount, (long)pa);
2024 if (nl > 18) {
2025 c = cngetc();
2026 if (c != ' ')
2027 return;
2028 nl = 0;
2029 }
2030 nl++;
2031 }
2032 }
2033}
2034#endif /* DDB */
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