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1.1 root 1: /*
2: * Mach Operating System
3: * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University.
4: * Copyright (c) 1993,1994 The University of Utah and
5: * the Computer Systems Laboratory (CSL).
6: * All rights reserved.
7: *
8: * Permission to use, copy, modify and distribute this software and its
9: * documentation is hereby granted, provided that both the copyright
10: * notice and this permission notice appear in all copies of the
11: * software, derivative works or modified versions, and any portions
12: * thereof, and that both notices appear in supporting documentation.
13: *
14: * CARNEGIE MELLON, THE UNIVERSITY OF UTAH AND CSL ALLOW FREE USE OF
15: * THIS SOFTWARE IN ITS "AS IS" CONDITION, AND DISCLAIM ANY LIABILITY
16: * OF ANY KIND FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF
17: * THIS SOFTWARE.
18: *
19: * Carnegie Mellon requests users of this software to return to
20: *
21: * Software Distribution Coordinator or [email protected]
22: * School of Computer Science
23: * Carnegie Mellon University
24: * Pittsburgh PA 15213-3890
25: *
26: * any improvements or extensions that they make and grant Carnegie Mellon
27: * the rights to redistribute these changes.
28: */
29: /*
30: * File: vm/memory_object.c
31: * Author: Michael Wayne Young
32: *
33: * External memory management interface control functions.
34: */
35:
36: /*
37: * Interface dependencies:
38: */
39:
40: #include <mach/std_types.h> /* For pointer_t */
41: #include <mach/mach_types.h>
42:
43: #include <mach/kern_return.h>
1.1.1.3 root 44: #include <vm/vm_map.h>
1.1 root 45: #include <vm/vm_object.h>
46: #include <mach/memory_object.h>
47: #include <mach/boolean.h>
48: #include <mach/vm_prot.h>
49: #include <mach/message.h>
50:
1.1.1.3 root 51: #include <vm/memory_object_user.user.h>
52: #include <vm/memory_object_default.user.h>
1.1 root 53:
54: /*
55: * Implementation dependencies:
56: */
57: #include <vm/memory_object.h>
58: #include <vm/vm_page.h>
59: #include <vm/vm_pageout.h>
60: #include <vm/pmap.h> /* For copy_to_phys, pmap_clear_modify */
1.1.1.3 root 61: #include <kern/debug.h> /* For panic() */
1.1 root 62: #include <kern/thread.h> /* For current_thread() */
63: #include <kern/host.h>
64: #include <vm/vm_kern.h> /* For kernel_map, vm_move */
65: #include <vm/vm_map.h> /* For vm_map_pageable */
66: #include <ipc/ipc_port.h>
67:
68: #if MACH_PAGEMAP
1.1.1.2 root 69: #include <vm/vm_external.h>
70: #endif /* MACH_PAGEMAP */
1.1 root 71:
72: typedef int memory_object_lock_result_t; /* moved from below */
73:
74:
75: ipc_port_t memory_manager_default = IP_NULL;
76: decl_simple_lock_data(,memory_manager_default_lock)
77:
78: /*
79: * Important note:
80: * All of these routines gain a reference to the
81: * object (first argument) as part of the automatic
82: * argument conversion. Explicit deallocation is necessary.
83: */
84:
1.1.1.4 root 85: kern_return_t memory_object_data_supply(
86: vm_object_t object,
87: vm_offset_t offset,
88: vm_map_copy_t data_copy,
89: unsigned int data_cnt,
90: vm_prot_t lock_value,
91: boolean_t precious,
92: ipc_port_t reply_to,
93: mach_msg_type_name_t reply_to_type)
1.1 root 94: {
95: kern_return_t result = KERN_SUCCESS;
96: vm_offset_t error_offset = 0;
97: vm_page_t m;
98: vm_page_t data_m;
99: vm_size_t original_length;
100: vm_offset_t original_offset;
101: vm_page_t *page_list;
102: boolean_t was_absent;
103: vm_map_copy_t orig_copy = data_copy;
104:
105: /*
106: * Look for bogus arguments
107: */
108:
109: if (object == VM_OBJECT_NULL) {
110: return(KERN_INVALID_ARGUMENT);
111: }
112:
113: if (lock_value & ~VM_PROT_ALL) {
114: vm_object_deallocate(object);
115: return(KERN_INVALID_ARGUMENT);
116: }
117:
118: if ((data_cnt % PAGE_SIZE) != 0) {
119: vm_object_deallocate(object);
120: return(KERN_INVALID_ARGUMENT);
121: }
122:
123: /*
124: * Adjust the offset from the memory object to the offset
125: * within the vm_object.
126: */
127:
128: original_length = data_cnt;
129: original_offset = offset;
130:
131: assert(data_copy->type == VM_MAP_COPY_PAGE_LIST);
132: page_list = &data_copy->cpy_page_list[0];
133:
134: vm_object_lock(object);
135: vm_object_paging_begin(object);
136: offset -= object->paging_offset;
137:
138: /*
139: * Loop over copy stealing pages for pagein.
140: */
141:
142: for (; data_cnt > 0 ; data_cnt -= PAGE_SIZE, offset += PAGE_SIZE) {
143:
144: assert(data_copy->cpy_npages > 0);
145: data_m = *page_list;
146:
147: if (data_m == VM_PAGE_NULL || data_m->tabled ||
148: data_m->error || data_m->absent || data_m->fictitious) {
149:
150: panic("Data_supply: bad page");
151: }
152:
153: /*
154: * Look up target page and check its state.
155: */
156:
157: retry_lookup:
158: m = vm_page_lookup(object,offset);
159: if (m == VM_PAGE_NULL) {
160: was_absent = FALSE;
161: }
162: else {
163: if (m->absent && m->busy) {
164:
165: /*
166: * Page was requested. Free the busy
167: * page waiting for it. Insertion
168: * of new page happens below.
169: */
170:
171: VM_PAGE_FREE(m);
172: was_absent = TRUE;
173: }
174: else {
175:
176: /*
177: * Have to wait for page that is busy and
178: * not absent. This is probably going to
179: * be an error, but go back and check.
180: */
181: if (m->busy) {
182: PAGE_ASSERT_WAIT(m, FALSE);
183: vm_object_unlock(object);
184: thread_block((void (*)()) 0);
185: vm_object_lock(object);
186: goto retry_lookup;
187: }
188:
189: /*
190: * Page already present; error.
191: * This is an error if data is precious.
192: */
193: result = KERN_MEMORY_PRESENT;
194: error_offset = offset + object->paging_offset;
195:
196: break;
197: }
198: }
199:
200: /*
201: * Ok to pagein page. Target object now has no page
202: * at offset. Set the page parameters, then drop
203: * in new page and set up pageout state. Object is
204: * still locked here.
205: *
206: * Must clear busy bit in page before inserting it.
207: * Ok to skip wakeup logic because nobody else
208: * can possibly know about this page.
209: */
210:
211: data_m->busy = FALSE;
212: data_m->dirty = FALSE;
213: pmap_clear_modify(data_m->phys_addr);
214:
215: data_m->page_lock = lock_value;
216: data_m->unlock_request = VM_PROT_NONE;
217: data_m->precious = precious;
218:
219: vm_page_lock_queues();
220: vm_page_insert(data_m, object, offset);
221:
222: if (was_absent)
223: vm_page_activate(data_m);
224: else
225: vm_page_deactivate(data_m);
226:
227: vm_page_unlock_queues();
228:
229: /*
230: * Null out this page list entry, and advance to next
231: * page.
232: */
233:
234: *page_list++ = VM_PAGE_NULL;
235:
236: if (--(data_copy->cpy_npages) == 0 &&
237: vm_map_copy_has_cont(data_copy)) {
238: vm_map_copy_t new_copy;
239:
240: vm_object_unlock(object);
241:
242: vm_map_copy_invoke_cont(data_copy, &new_copy, &result);
243:
244: if (result == KERN_SUCCESS) {
245:
246: /*
247: * Consume on success requires that
248: * we keep the original vm_map_copy
249: * around in case something fails.
250: * Free the old copy if it's not the original
251: */
252: if (data_copy != orig_copy) {
253: vm_map_copy_discard(data_copy);
254: }
255:
256: if ((data_copy = new_copy) != VM_MAP_COPY_NULL)
257: page_list = &data_copy->cpy_page_list[0];
258:
259: vm_object_lock(object);
260: }
261: else {
262: vm_object_lock(object);
263: error_offset = offset + object->paging_offset +
264: PAGE_SIZE;
265: break;
266: }
267: }
268: }
269:
270: /*
271: * Send reply if one was requested.
272: */
273: vm_object_paging_end(object);
274: vm_object_unlock(object);
275:
276: if (vm_map_copy_has_cont(data_copy))
277: vm_map_copy_abort_cont(data_copy);
278:
279: if (IP_VALID(reply_to)) {
280: memory_object_supply_completed(
281: reply_to, reply_to_type,
282: object->pager_request,
283: original_offset,
284: original_length,
285: result,
286: error_offset);
287: }
288:
289: vm_object_deallocate(object);
290:
291: /*
292: * Consume on success: The final data copy must be
293: * be discarded if it is not the original. The original
294: * gets discarded only if this routine succeeds.
295: */
296: if (data_copy != orig_copy)
297: vm_map_copy_discard(data_copy);
298: if (result == KERN_SUCCESS)
299: vm_map_copy_discard(orig_copy);
300:
301:
302: return(result);
303: }
304:
1.1.1.4 root 305: kern_return_t memory_object_data_error(
306: vm_object_t object,
307: vm_offset_t offset,
308: vm_size_t size,
309: kern_return_t error_value)
1.1 root 310: {
311: if (object == VM_OBJECT_NULL)
312: return(KERN_INVALID_ARGUMENT);
313:
314: if (size != round_page(size))
315: return(KERN_INVALID_ARGUMENT);
316:
317: vm_object_lock(object);
318: offset -= object->paging_offset;
319:
320: while (size != 0) {
1.1.1.4 root 321: vm_page_t m;
1.1 root 322:
323: m = vm_page_lookup(object, offset);
324: if ((m != VM_PAGE_NULL) && m->busy && m->absent) {
325: m->error = TRUE;
326: m->absent = FALSE;
327: vm_object_absent_release(object);
328:
329: PAGE_WAKEUP_DONE(m);
330:
331: vm_page_lock_queues();
332: vm_page_activate(m);
333: vm_page_unlock_queues();
334: }
335:
336: size -= PAGE_SIZE;
337: offset += PAGE_SIZE;
338: }
339: vm_object_unlock(object);
340:
341: vm_object_deallocate(object);
342: return(KERN_SUCCESS);
343: }
344:
1.1.1.4 root 345: kern_return_t memory_object_data_unavailable(
346: vm_object_t object,
347: vm_offset_t offset,
348: vm_size_t size)
1.1 root 349: {
350: #if MACH_PAGEMAP
351: vm_external_t existence_info = VM_EXTERNAL_NULL;
1.1.1.2 root 352: #endif /* MACH_PAGEMAP */
1.1 root 353:
354: if (object == VM_OBJECT_NULL)
355: return(KERN_INVALID_ARGUMENT);
356:
357: if (size != round_page(size))
358: return(KERN_INVALID_ARGUMENT);
359:
360: #if MACH_PAGEMAP
1.1.1.2 root 361: if ((offset == 0) && (size > VM_EXTERNAL_LARGE_SIZE) &&
1.1 root 362: (object->existence_info == VM_EXTERNAL_NULL)) {
363: existence_info = vm_external_create(VM_EXTERNAL_SMALL_SIZE);
364: }
1.1.1.2 root 365: #endif /* MACH_PAGEMAP */
1.1 root 366:
367: vm_object_lock(object);
368: #if MACH_PAGEMAP
369: if (existence_info != VM_EXTERNAL_NULL) {
370: object->existence_info = existence_info;
371: }
372: if ((offset == 0) && (size > VM_EXTERNAL_LARGE_SIZE)) {
373: vm_object_unlock(object);
374: vm_object_deallocate(object);
375: return(KERN_SUCCESS);
376: }
1.1.1.2 root 377: #endif /* MACH_PAGEMAP */
1.1 root 378: offset -= object->paging_offset;
379:
380: while (size != 0) {
1.1.1.4 root 381: vm_page_t m;
1.1 root 382:
383: /*
384: * We're looking for pages that are both busy and
385: * absent (waiting to be filled), converting them
386: * to just absent.
387: *
388: * Pages that are just busy can be ignored entirely.
389: */
390:
391: m = vm_page_lookup(object, offset);
392: if ((m != VM_PAGE_NULL) && m->busy && m->absent) {
393: PAGE_WAKEUP_DONE(m);
394:
395: vm_page_lock_queues();
396: vm_page_activate(m);
397: vm_page_unlock_queues();
398: }
399: size -= PAGE_SIZE;
400: offset += PAGE_SIZE;
401: }
402:
403: vm_object_unlock(object);
404:
405: vm_object_deallocate(object);
406: return(KERN_SUCCESS);
407: }
408:
409: /*
410: * Routine: memory_object_lock_page
411: *
412: * Description:
413: * Perform the appropriate lock operations on the
414: * given page. See the description of
415: * "memory_object_lock_request" for the meanings
416: * of the arguments.
417: *
418: * Returns an indication that the operation
419: * completed, blocked, or that the page must
420: * be cleaned.
421: */
422:
423: #define MEMORY_OBJECT_LOCK_RESULT_DONE 0
424: #define MEMORY_OBJECT_LOCK_RESULT_MUST_BLOCK 1
425: #define MEMORY_OBJECT_LOCK_RESULT_MUST_CLEAN 2
426: #define MEMORY_OBJECT_LOCK_RESULT_MUST_RETURN 3
427:
1.1.1.4 root 428: memory_object_lock_result_t memory_object_lock_page(
429: vm_page_t m,
430: memory_object_return_t should_return,
431: boolean_t should_flush,
432: vm_prot_t prot)
1.1 root 433: {
434: /*
435: * Don't worry about pages for which the kernel
436: * does not have any data.
437: */
438:
439: if (m->absent)
440: return(MEMORY_OBJECT_LOCK_RESULT_DONE);
441:
442: /*
443: * If we cannot change access to the page,
444: * either because a mapping is in progress
445: * (busy page) or because a mapping has been
446: * wired, then give up.
447: */
448:
449: if (m->busy)
450: return(MEMORY_OBJECT_LOCK_RESULT_MUST_BLOCK);
451:
452: assert(!m->fictitious);
453:
454: if (m->wire_count != 0) {
455: /*
456: * If no change would take place
457: * anyway, return successfully.
458: *
459: * No change means:
460: * Not flushing AND
461: * No change to page lock [2 checks] AND
462: * Don't need to send page to manager
463: *
464: * Don't need to send page to manager means:
465: * No clean or return request OR (
466: * Page is not dirty [2 checks] AND (
467: * Page is not precious OR
468: * No request to return precious pages ))
1.1.1.2 root 469: *
1.1 root 470: * Now isn't that straightforward and obvious ?? ;-)
471: *
472: * XXX This doesn't handle sending a copy of a wired
473: * XXX page to the pager, but that will require some
474: * XXX significant surgery.
475: */
476:
477: if (!should_flush &&
478: ((m->page_lock == prot) || (prot == VM_PROT_NO_CHANGE)) &&
479: ((should_return == MEMORY_OBJECT_RETURN_NONE) ||
480: (!m->dirty && !pmap_is_modified(m->phys_addr) &&
481: (!m->precious ||
482: should_return != MEMORY_OBJECT_RETURN_ALL)))) {
483: /*
484: * Restart page unlock requests,
485: * even though no change took place.
486: * [Memory managers may be expecting
487: * to see new requests.]
488: */
489: m->unlock_request = VM_PROT_NONE;
490: PAGE_WAKEUP(m);
491:
492: return(MEMORY_OBJECT_LOCK_RESULT_DONE);
493: }
494:
495: return(MEMORY_OBJECT_LOCK_RESULT_MUST_BLOCK);
496: }
497:
498: /*
499: * If the page is to be flushed, allow
500: * that to be done as part of the protection.
501: */
502:
503: if (should_flush)
504: prot = VM_PROT_ALL;
505:
506: /*
507: * Set the page lock.
508: *
509: * If we are decreasing permission, do it now;
510: * let the fault handler take care of increases
511: * (pmap_page_protect may not increase protection).
512: */
513:
514: if (prot != VM_PROT_NO_CHANGE) {
515: if ((m->page_lock ^ prot) & prot) {
516: pmap_page_protect(m->phys_addr, VM_PROT_ALL & ~prot);
517: }
518: m->page_lock = prot;
519:
520: /*
521: * Restart any past unlock requests, even if no
522: * change resulted. If the manager explicitly
523: * requested no protection change, then it is assumed
524: * to be remembering past requests.
525: */
526:
527: m->unlock_request = VM_PROT_NONE;
528: PAGE_WAKEUP(m);
529: }
530:
531: /*
532: * Handle cleaning.
533: */
534:
535: if (should_return != MEMORY_OBJECT_RETURN_NONE) {
536: /*
537: * Check whether the page is dirty. If
538: * write permission has not been removed,
539: * this may have unpredictable results.
540: */
541:
542: if (!m->dirty)
543: m->dirty = pmap_is_modified(m->phys_addr);
544:
545: if (m->dirty || (m->precious &&
546: should_return == MEMORY_OBJECT_RETURN_ALL)) {
547: /*
548: * If we weren't planning
549: * to flush the page anyway,
550: * we may need to remove the
551: * page from the pageout
552: * system and from physical
553: * maps now.
554: */
555:
556: vm_page_lock_queues();
557: VM_PAGE_QUEUES_REMOVE(m);
558: vm_page_unlock_queues();
559:
560: if (!should_flush)
561: pmap_page_protect(m->phys_addr,
562: VM_PROT_NONE);
563:
564: /*
565: * Cleaning a page will cause
566: * it to be flushed.
567: */
568:
569: if (m->dirty)
570: return(MEMORY_OBJECT_LOCK_RESULT_MUST_CLEAN);
571: else
572: return(MEMORY_OBJECT_LOCK_RESULT_MUST_RETURN);
573: }
574: }
575:
576: /*
577: * Handle flushing
578: */
579:
580: if (should_flush) {
581: VM_PAGE_FREE(m);
582: } else {
583: extern boolean_t vm_page_deactivate_hint;
584:
585: /*
586: * XXX Make clean but not flush a paging hint,
587: * and deactivate the pages. This is a hack
588: * because it overloads flush/clean with
589: * implementation-dependent meaning. This only
590: * happens to pages that are already clean.
591: */
592:
593: if (vm_page_deactivate_hint &&
594: (should_return != MEMORY_OBJECT_RETURN_NONE)) {
595: vm_page_lock_queues();
596: vm_page_deactivate(m);
597: vm_page_unlock_queues();
598: }
599: }
600:
601: return(MEMORY_OBJECT_LOCK_RESULT_DONE);
602: }
603:
604: /*
605: * Routine: memory_object_lock_request [user interface]
606: *
607: * Description:
608: * Control use of the data associated with the given
609: * memory object. For each page in the given range,
610: * perform the following operations, in order:
611: * 1) restrict access to the page (disallow
612: * forms specified by "prot");
613: * 2) return data to the manager (if "should_return"
614: * is RETURN_DIRTY and the page is dirty, or
615: * "should_return" is RETURN_ALL and the page
616: * is either dirty or precious); and,
617: * 3) flush the cached copy (if "should_flush"
618: * is asserted).
619: * The set of pages is defined by a starting offset
620: * ("offset") and size ("size"). Only pages with the
621: * same page alignment as the starting offset are
622: * considered.
623: *
624: * A single acknowledgement is sent (to the "reply_to"
625: * port) when these actions are complete. If successful,
626: * the naked send right for reply_to is consumed.
627: */
628:
629: kern_return_t
1.1.1.4 root 630: memory_object_lock_request(
631: vm_object_t object,
632: vm_offset_t offset,
633: vm_size_t size,
634: memory_object_return_t should_return,
635: boolean_t should_flush,
636: vm_prot_t prot,
637: ipc_port_t reply_to,
638: mach_msg_type_name_t reply_to_type)
1.1 root 639: {
1.1.1.4 root 640: vm_page_t m;
1.1 root 641: vm_offset_t original_offset = offset;
642: vm_size_t original_size = size;
643: vm_offset_t paging_offset = 0;
644: vm_object_t new_object = VM_OBJECT_NULL;
645: vm_offset_t new_offset = 0;
646: vm_offset_t last_offset = offset;
647: int page_lock_result;
648: int pageout_action = 0; /* '=0' to quiet lint */
649:
650: #define DATA_WRITE_MAX 32
651: vm_page_t holding_pages[DATA_WRITE_MAX];
652:
653: /*
654: * Check for bogus arguments.
655: */
656: if (object == VM_OBJECT_NULL ||
657: ((prot & ~VM_PROT_ALL) != 0 && prot != VM_PROT_NO_CHANGE))
658: return (KERN_INVALID_ARGUMENT);
659:
660: size = round_page(size);
661:
662: /*
663: * Lock the object, and acquire a paging reference to
664: * prevent the memory_object and control ports from
665: * being destroyed.
666: */
667:
668: vm_object_lock(object);
669: vm_object_paging_begin(object);
670: offset -= object->paging_offset;
671:
672: /*
673: * To avoid blocking while scanning for pages, save
674: * dirty pages to be cleaned all at once.
675: *
676: * XXXO A similar strategy could be used to limit the
677: * number of times that a scan must be restarted for
678: * other reasons. Those pages that would require blocking
679: * could be temporarily collected in another list, or
680: * their offsets could be recorded in a small array.
681: */
682:
683: /*
684: * XXX NOTE: May want to consider converting this to a page list
685: * XXX vm_map_copy interface. Need to understand object
686: * XXX coalescing implications before doing so.
687: */
688:
689: #define PAGEOUT_PAGES \
690: MACRO_BEGIN \
691: vm_map_copy_t copy; \
1.1.1.5 root 692: unsigned i; \
1.1.1.4 root 693: vm_page_t hp; \
1.1 root 694: \
695: vm_object_unlock(object); \
696: \
697: (void) vm_map_copyin_object(new_object, 0, new_offset, ©); \
698: \
1.1.1.6 ! root 699: (void) memory_object_data_return( \
! 700: object->pager, \
! 701: object->pager_request, \
! 702: paging_offset, \
! 703: (pointer_t) copy, \
! 704: new_offset, \
1.1 root 705: (pageout_action == MEMORY_OBJECT_LOCK_RESULT_MUST_CLEAN), \
1.1.1.6 ! root 706: !should_flush); \
1.1 root 707: \
708: vm_object_lock(object); \
709: \
710: for (i = 0; i < atop(new_offset); i++) { \
711: hp = holding_pages[i]; \
712: if (hp != VM_PAGE_NULL) \
713: VM_PAGE_FREE(hp); \
714: } \
715: \
716: new_object = VM_OBJECT_NULL; \
717: MACRO_END
718:
719: for (;
720: size != 0;
721: size -= PAGE_SIZE, offset += PAGE_SIZE)
722: {
723: /*
724: * Limit the number of pages to be cleaned at once.
725: */
726: if (new_object != VM_OBJECT_NULL &&
727: new_offset >= PAGE_SIZE * DATA_WRITE_MAX)
728: {
729: PAGEOUT_PAGES;
730: }
731:
732: while ((m = vm_page_lookup(object, offset)) != VM_PAGE_NULL) {
733: switch ((page_lock_result = memory_object_lock_page(m,
734: should_return,
735: should_flush,
736: prot)))
737: {
738: case MEMORY_OBJECT_LOCK_RESULT_DONE:
739: /*
740: * End of a cluster of dirty pages.
741: */
742: if (new_object != VM_OBJECT_NULL) {
743: PAGEOUT_PAGES;
744: continue;
745: }
746: break;
747:
748: case MEMORY_OBJECT_LOCK_RESULT_MUST_BLOCK:
749: /*
750: * Since it is necessary to block,
751: * clean any dirty pages now.
752: */
753: if (new_object != VM_OBJECT_NULL) {
754: PAGEOUT_PAGES;
755: continue;
756: }
757:
758: PAGE_ASSERT_WAIT(m, FALSE);
759: vm_object_unlock(object);
760: thread_block((void (*)()) 0);
761: vm_object_lock(object);
762: continue;
763:
764: case MEMORY_OBJECT_LOCK_RESULT_MUST_CLEAN:
765: case MEMORY_OBJECT_LOCK_RESULT_MUST_RETURN:
766: /*
767: * The clean and return cases are similar.
768: *
769: * Mark the page busy since we unlock the
770: * object below.
771: */
772: m->busy = TRUE;
773:
774: /*
775: * if this would form a discontiguous block,
776: * clean the old pages and start anew.
777: *
778: * NOTE: The first time through here, new_object
779: * is null, hiding the fact that pageout_action
780: * is not initialized.
781: */
782: if (new_object != VM_OBJECT_NULL &&
783: (last_offset != offset ||
784: pageout_action != page_lock_result)) {
785: PAGEOUT_PAGES;
786: }
787:
788: vm_object_unlock(object);
789:
790: /*
791: * If we have not already allocated an object
792: * for a range of pages to be written, do so
793: * now.
794: */
795: if (new_object == VM_OBJECT_NULL) {
796: new_object = vm_object_allocate(original_size);
797: new_offset = 0;
798: paging_offset = m->offset +
799: object->paging_offset;
800: pageout_action = page_lock_result;
801: }
802:
803: /*
804: * Move or copy the dirty page into the
805: * new object.
806: */
807: m = vm_pageout_setup(m,
808: m->offset + object->paging_offset,
809: new_object,
810: new_offset,
811: should_flush);
812:
813: /*
814: * Save the holding page if there is one.
815: */
816: holding_pages[atop(new_offset)] = m;
817: new_offset += PAGE_SIZE;
818: last_offset = offset + PAGE_SIZE;
819:
820: vm_object_lock(object);
821: break;
822: }
823: break;
824: }
825: }
826:
827: /*
828: * We have completed the scan for applicable pages.
829: * Clean any pages that have been saved.
830: */
831: if (new_object != VM_OBJECT_NULL) {
832: PAGEOUT_PAGES;
833: }
834:
835: if (IP_VALID(reply_to)) {
836: vm_object_unlock(object);
837:
838: /* consumes our naked send-once/send right for reply_to */
839: (void) memory_object_lock_completed(reply_to, reply_to_type,
840: object->pager_request, original_offset, original_size);
841:
842: vm_object_lock(object);
843: }
844:
845: vm_object_paging_end(object);
846: vm_object_unlock(object);
847: vm_object_deallocate(object);
848:
849: return (KERN_SUCCESS);
850: }
851:
1.1.1.6 ! root 852: static kern_return_t
1.1.1.4 root 853: memory_object_set_attributes_common(
854: vm_object_t object,
855: boolean_t may_cache,
1.1.1.6 ! root 856: memory_object_copy_strategy_t copy_strategy)
1.1 root 857: {
858: if (object == VM_OBJECT_NULL)
859: return(KERN_INVALID_ARGUMENT);
860:
861: /*
862: * Verify the attributes of importance
863: */
864:
865: switch(copy_strategy) {
866: case MEMORY_OBJECT_COPY_NONE:
867: case MEMORY_OBJECT_COPY_CALL:
868: case MEMORY_OBJECT_COPY_DELAY:
869: case MEMORY_OBJECT_COPY_TEMPORARY:
870: break;
871: default:
872: vm_object_deallocate(object);
873: return(KERN_INVALID_ARGUMENT);
874: }
875:
876: if (may_cache)
877: may_cache = TRUE;
878:
879: vm_object_lock(object);
880:
881: /*
882: * Wake up anyone waiting for the ready attribute
883: * to become asserted.
884: */
885:
1.1.1.6 ! root 886: if (!object->pager_ready) {
1.1 root 887: vm_object_wakeup(object, VM_OBJECT_EVENT_PAGER_READY);
888: }
889:
890: /*
891: * Copy the attributes
892: */
893:
894: object->can_persist = may_cache;
1.1.1.6 ! root 895: object->pager_ready = TRUE;
1.1 root 896: if (copy_strategy == MEMORY_OBJECT_COPY_TEMPORARY) {
897: object->temporary = TRUE;
898: } else {
899: object->copy_strategy = copy_strategy;
900: }
901:
902: vm_object_unlock(object);
903:
904: vm_object_deallocate(object);
905:
906: return(KERN_SUCCESS);
907: }
908:
909: /*
910: * XXX rpd claims that reply_to could be obviated in favor of a client
911: * XXX stub that made change_attributes an RPC. Need investigation.
912: */
913:
1.1.1.4 root 914: kern_return_t memory_object_change_attributes(
915: vm_object_t object,
916: boolean_t may_cache,
917: memory_object_copy_strategy_t copy_strategy,
918: ipc_port_t reply_to,
919: mach_msg_type_name_t reply_to_type)
1.1 root 920: {
921: kern_return_t result;
922:
923: /*
924: * Do the work and throw away our object reference. It
925: * is important that the object reference be deallocated
926: * BEFORE sending the reply. The whole point of the reply
927: * is that it shows up after the terminate message that
928: * may be generated by setting the object uncacheable.
929: *
930: * XXX may_cache may become a tri-valued variable to handle
931: * XXX uncache if not in use.
932: */
1.1.1.6 ! root 933: result = memory_object_set_attributes_common(object, may_cache,
! 934: copy_strategy);
1.1 root 935:
936: if (IP_VALID(reply_to)) {
937:
938: /* consumes our naked send-once/send right for reply_to */
939: (void) memory_object_change_completed(reply_to, reply_to_type,
940: may_cache, copy_strategy);
941:
942: }
943:
944: return(result);
945: }
946:
1.1.1.4 root 947: kern_return_t memory_object_ready(
948: vm_object_t object,
949: boolean_t may_cache,
950: memory_object_copy_strategy_t copy_strategy)
1.1 root 951: {
1.1.1.6 ! root 952: return memory_object_set_attributes_common(object, may_cache,
! 953: copy_strategy);
1.1 root 954: }
955:
1.1.1.4 root 956: kern_return_t memory_object_get_attributes(
957: vm_object_t object,
958: boolean_t *object_ready,
959: boolean_t *may_cache,
960: memory_object_copy_strategy_t *copy_strategy)
1.1 root 961: {
962: if (object == VM_OBJECT_NULL)
963: return(KERN_INVALID_ARGUMENT);
964:
965: vm_object_lock(object);
966: *may_cache = object->can_persist;
967: *object_ready = object->pager_ready;
968: *copy_strategy = object->copy_strategy;
969: vm_object_unlock(object);
970:
971: vm_object_deallocate(object);
972:
973: return(KERN_SUCCESS);
974: }
975:
976: /*
977: * If successful, consumes the supplied naked send right.
978: */
979: kern_return_t vm_set_default_memory_manager(host, default_manager)
1.1.1.4 root 980: const host_t host;
1.1 root 981: ipc_port_t *default_manager;
982: {
983: ipc_port_t current_manager;
984: ipc_port_t new_manager;
985: ipc_port_t returned_manager;
986:
987: if (host == HOST_NULL)
988: return(KERN_INVALID_HOST);
989:
990: new_manager = *default_manager;
991: simple_lock(&memory_manager_default_lock);
992: current_manager = memory_manager_default;
993:
994: if (new_manager == IP_NULL) {
995: /*
996: * Retrieve the current value.
997: */
998:
999: returned_manager = ipc_port_copy_send(current_manager);
1000: } else {
1001: /*
1002: * Retrieve the current value,
1003: * and replace it with the supplied value.
1004: * We consume the supplied naked send right.
1005: */
1006:
1007: returned_manager = current_manager;
1008: memory_manager_default = new_manager;
1009:
1010: /*
1011: * In case anyone's been waiting for a memory
1012: * manager to be established, wake them up.
1013: */
1014:
1015: thread_wakeup((event_t) &memory_manager_default);
1016: }
1017:
1018: simple_unlock(&memory_manager_default_lock);
1019:
1020: *default_manager = returned_manager;
1021: return(KERN_SUCCESS);
1022: }
1023:
1024: /*
1025: * Routine: memory_manager_default_reference
1026: * Purpose:
1027: * Returns a naked send right for the default
1028: * memory manager. The returned right is always
1029: * valid (not IP_NULL or IP_DEAD).
1030: */
1031:
1.1.1.3 root 1032: ipc_port_t memory_manager_default_reference(void)
1.1 root 1033: {
1034: ipc_port_t current_manager;
1035:
1036: simple_lock(&memory_manager_default_lock);
1037:
1038: while (current_manager = ipc_port_copy_send(memory_manager_default),
1039: !IP_VALID(current_manager)) {
1040: thread_sleep((event_t) &memory_manager_default,
1041: simple_lock_addr(memory_manager_default_lock),
1042: FALSE);
1043: simple_lock(&memory_manager_default_lock);
1044: }
1045:
1046: simple_unlock(&memory_manager_default_lock);
1047:
1048: return current_manager;
1049: }
1050:
1051: /*
1052: * Routine: memory_manager_default_port
1053: * Purpose:
1054: * Returns true if the receiver for the port
1055: * is the default memory manager.
1056: *
1057: * This is a hack to let ds_read_done
1058: * know when it should keep memory wired.
1059: */
1060:
1061: boolean_t memory_manager_default_port(port)
1.1.1.4 root 1062: const ipc_port_t port;
1.1 root 1063: {
1064: ipc_port_t current;
1065: boolean_t result;
1066:
1067: simple_lock(&memory_manager_default_lock);
1068: current = memory_manager_default;
1069: if (IP_VALID(current)) {
1070: /*
1071: * There is no point in bothering to lock
1072: * both ports, which would be painful to do.
1073: * If the receive rights are moving around,
1074: * we might be inaccurate.
1075: */
1076:
1077: result = port->ip_receiver == current->ip_receiver;
1078: } else
1079: result = FALSE;
1080: simple_unlock(&memory_manager_default_lock);
1081:
1082: return result;
1083: }
1084:
1.1.1.3 root 1085: void memory_manager_default_init(void)
1.1 root 1086: {
1087: memory_manager_default = IP_NULL;
1088: simple_lock_init(&memory_manager_default_lock);
1089: }
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