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1 /*
2 * Copyright (c) 2000-2003, 2005-2009 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28 /*
29 File: BTreeAllocate.c
30
31 Contains: BTree Node Allocation routines for the BTree Module.
32
33 Version: xxx put the technology version here xxx
34
35 Written by: Gordon Sheridan and Bill Bruffey
36
37 Copyright: © 1992-1999 by Apple Computer, Inc., all rights reserved.
38
39 File Ownership:
40
41 DRI: Don Brady
42
43 Other Contact: Mark Day
44
45 Technology: File Systems
46
47 Writers:
48
49 (djb) Don Brady
50 (ser) Scott Roberts
51 (msd) Mark Day
52
53 Change History (most recent first):
54
55 <MOSXS> 6/1/99 djb Sync up with Mac OS 8.6.
56 <CS3> 11/24/97 djb Remove some debug code (Panic calls).
57 <CS2> 7/24/97 djb CallbackProcs now take refnum instead of an FCB.
58 <CS1> 4/23/97 djb first checked in
59
60 <HFS2> 2/19/97 djb Change E_BadNodeType to fsBTBadNodeType.
61 <HFS1> 12/19/96 djb first checked in
62
63 History applicable to original Scarecrow Design:
64
65 <4> 10/25/96 ser Changing for new VFPI
66 <3> 10/18/96 ser Converting over VFPI changes
67 <2> 1/10/96 msd Change 64-bit math to use real function names from Math64.i.
68 <1> 10/18/95 rst Moved from Scarecrow project.
69
70 <8> 1/12/95 wjk Adopt Model FileSystem changes in D5.
71 <7> 9/30/94 prp Get in sync with D2 interface changes.
72 <6> 7/22/94 wjk Convert to the new set of header files.
73 <5> 8/31/93 prp Use U64SetU instead of S64Set.
74 <4> 5/21/93 gs Fix ExtendBTree bug.
75 <3> 5/10/93 gs Fix pointer arithmetic bug in AllocateNode.
76 <2> 3/23/93 gs finish ExtendBTree routine.
77 <1> 2/8/93 gs first checked in
78 <0> 1/1/93 gs begin AllocateNode and FreeNode
79
80 */
81
82 #include "../../hfs_btreeio.h"
83 #include "../../hfs_endian.h"
84 #include "../headers/BTreesPrivate.h"
85
86 ///////////////////// Routines Internal To BTreeAllocate.c //////////////////////
87
88 static OSStatus GetMapNode (BTreeControlBlockPtr btreePtr,
89 BlockDescriptor *nodePtr,
90 u_int16_t **mapPtr,
91 u_int16_t *mapSize );
92
93 /////////////////////////////////////////////////////////////////////////////////
94
95 /*-------------------------------------------------------------------------------
96
97 Routine: AllocateNode - Find Free Node, Mark It Used, and Return Node Number.
98
99 Function: Searches the map records for the first free node, marks it "in use" and
100 returns the node number found. This routine should really only be called
101 when we know there are free blocks, otherwise it's just a waste of time.
102
103 Note: We have to examine map nodes a word at a time rather than a long word
104 because the External BTree Mgr used map records that were not an integral
105 number of long words. Too bad. In our spare time could develop a more
106 sophisticated algorithm that read map records by long words (and long
107 word aligned) and handled the spare bytes at the beginning and end
108 appropriately.
109
110 Input: btreePtr - pointer to control block for BTree file
111
112 Output: nodeNum - number of node allocated
113
114
115 Result: noErr - success
116 fsBTNoMoreMapNodesErr - no free blocks were found
117 != noErr - failure
118 -------------------------------------------------------------------------------*/
119
120 OSStatus AllocateNode (BTreeControlBlockPtr btreePtr, u_int32_t *nodeNum)
121 {
122 OSStatus err;
123 BlockDescriptor node;
124 u_int16_t *mapPtr, *pos;
125 u_int16_t mapSize, size;
126 u_int16_t freeWord;
127 u_int16_t mask;
128 u_int16_t bitOffset;
129 u_int32_t nodeNumber;
130
131
132 nodeNumber = 0; // first node number of header map record
133 node.buffer = nil; // clear node.buffer to get header node
134 // - and for ErrorExit
135 node.blockHeader = nil;
136
137 while (true)
138 {
139 err = GetMapNode (btreePtr, &node, &mapPtr, &mapSize);
140 M_ExitOnError (err);
141
142 // XXXdbg
143 ModifyBlockStart(btreePtr->fileRefNum, &node);
144
145 //////////////////////// Find Word with Free Bit ////////////////////////////
146
147 pos = mapPtr;
148 size = mapSize;
149 size >>= 1; // convert to number of words
150 //\80\80 assumes mapRecords contain an integral number of words
151
152 while ( size-- )
153 {
154 if ( *pos++ != 0xFFFF ) // assume test fails, and increment pos
155 break;
156 }
157
158 --pos; // whoa! backup
159
160 if (*pos != 0xFFFF) // hey, we got one!
161 break;
162
163 nodeNumber += mapSize << 3; // covert to number of bits (nodes)
164 }
165
166 ///////////////////////// Find Free Bit in Word /////////////////////////////
167
168 freeWord = SWAP_BE16 (*pos);
169 bitOffset = 15;
170 mask = 0x8000;
171
172 do {
173 if ( (freeWord & mask) == 0)
174 break;
175 mask >>= 1;
176 } while (--bitOffset);
177
178 ////////////////////// Calculate Free Node Number ///////////////////////////
179
180 nodeNumber += ((pos - mapPtr) << 4) + (15 - bitOffset); // (pos-mapPtr) = # of words!
181
182
183 ///////////////////////// Check for End of Map //////////////////////////////
184
185 if (nodeNumber >= btreePtr->totalNodes)
186 {
187 err = fsBTFullErr;
188 goto ErrorExit;
189 }
190
191 /////////////////////////// Allocate the Node ///////////////////////////////
192
193 *pos |= SWAP_BE16 (mask); // set the map bit for the node
194
195 err = UpdateNode (btreePtr, &node, 0, kLockTransaction);
196 M_ExitOnError (err);
197
198 --btreePtr->freeNodes;
199 btreePtr->flags |= kBTHeaderDirty;
200
201 /* Account for allocations from node reserve */
202 BTUpdateReserve(btreePtr, 1);
203
204 *nodeNum = nodeNumber;
205
206 return noErr;
207
208 ////////////////////////////////// Error Exit ///////////////////////////////////
209
210 ErrorExit:
211
212 (void) ReleaseNode (btreePtr, &node);
213 *nodeNum = 0;
214
215 return err;
216 }
217
218
219
220 /*-------------------------------------------------------------------------------
221
222 Routine: FreeNode - Clear allocation bit for node.
223
224 Function: Finds the bit representing the node specified by nodeNum in the node
225 map and clears the bit.
226
227
228 Input: btreePtr - pointer to control block for BTree file
229 nodeNum - number of node to mark free
230
231 Output: none
232
233 Result: noErr - success
234 fsBTNoMoreMapNodesErr - node number is beyond end of node map
235 != noErr - GetNode or ReleaseNode encountered some difficulty
236 -------------------------------------------------------------------------------*/
237
238 OSStatus FreeNode (BTreeControlBlockPtr btreePtr, u_int32_t nodeNum)
239 {
240 OSStatus err;
241 BlockDescriptor node;
242 u_int32_t nodeIndex;
243 u_int16_t mapSize;
244 u_int16_t *mapPos;
245 u_int16_t bitOffset;
246
247
248 //////////////////////////// Find Map Record ////////////////////////////////
249 nodeIndex = 0; // first node number of header map record
250 node.buffer = nil; // invalidate node.buffer to get header node
251 node.blockHeader = nil;
252
253 while (nodeNum >= nodeIndex)
254 {
255 err = GetMapNode (btreePtr, &node, &mapPos, &mapSize);
256 M_ExitOnError (err);
257
258 nodeIndex += mapSize << 3; // covert to number of bits (nodes)
259 }
260
261 //////////////////////////// Mark Node Free /////////////////////////////////
262
263 // XXXdbg
264 ModifyBlockStart(btreePtr->fileRefNum, &node);
265
266 nodeNum -= (nodeIndex - (mapSize << 3)); // relative to this map record
267 bitOffset = 15 - (nodeNum & 0x0000000F); // last 4 bits are bit offset
268 mapPos += nodeNum >> 4; // point to word containing map bit
269
270 M_SWAP_BE16_ClearBitNum (*mapPos, bitOffset); // clear it
271
272 err = UpdateNode (btreePtr, &node, 0, kLockTransaction);
273 M_ExitOnError (err);
274
275 ++btreePtr->freeNodes;
276 btreePtr->flags |= kBTHeaderDirty; // how about a macro for this
277
278 return noErr;
279
280 ErrorExit:
281
282 (void) ReleaseNode (btreePtr, &node);
283
284 return err;
285 }
286
287
288
289 /*-------------------------------------------------------------------------------
290
291 Routine: ExtendBTree - Call FSAgent to extend file, and allocate necessary map nodes.
292
293 Function: This routine calls the the FSAgent to extend the end of fork, if necessary,
294 to accomodate the number of nodes requested. It then allocates as many
295 map nodes as are necessary to account for all the nodes in the B*Tree.
296 If newTotalNodes is less than the current number of nodes, no action is
297 taken.
298
299 Note: Internal HFS File Manager BTree Module counts on an integral number of
300 long words in map records, although they are not long word aligned.
301
302 Input: btreePtr - pointer to control block for BTree file
303 newTotalNodes - total number of nodes the B*Tree is to extended to
304
305 Output: none
306
307 Result: noErr - success
308 != noErr - failure
309 -------------------------------------------------------------------------------*/
310
311 OSStatus ExtendBTree (BTreeControlBlockPtr btreePtr,
312 u_int32_t newTotalNodes )
313 {
314 OSStatus err;
315 FCB *filePtr;
316 FSSize minEOF, maxEOF;
317 u_int16_t nodeSize;
318 u_int32_t oldTotalNodes;
319 u_int32_t newMapNodes;
320 u_int32_t mapBits, totalMapBits;
321 u_int32_t recStartBit;
322 u_int32_t nodeNum, nextNodeNum;
323 u_int32_t firstNewMapNodeNum, lastNewMapNodeNum;
324 BlockDescriptor mapNode, newNode;
325 u_int16_t *mapPos;
326 u_int16_t *mapStart;
327 u_int16_t mapSize;
328 u_int16_t mapNodeRecSize;
329 u_int32_t bitInWord, bitInRecord;
330 u_int16_t mapIndex;
331
332
333 oldTotalNodes = btreePtr->totalNodes;
334 if (newTotalNodes <= oldTotalNodes) // we're done!
335 return noErr;
336
337 nodeSize = btreePtr->nodeSize;
338 filePtr = GetFileControlBlock(btreePtr->fileRefNum);
339
340 mapNode.buffer = nil;
341 mapNode.blockHeader = nil;
342 newNode.buffer = nil;
343 newNode.blockHeader = nil;
344
345 mapNodeRecSize = nodeSize - sizeof(BTNodeDescriptor) - 6; // 2 bytes of free space (see note)
346
347
348 //////////////////////// Count Bits In Node Map /////////////////////////////
349
350 totalMapBits = 0;
351 do {
352 err = GetMapNode (btreePtr, &mapNode, &mapStart, &mapSize);
353 M_ExitOnError (err);
354
355 mapBits = mapSize << 3; // mapSize (in bytes) * 8
356 recStartBit = totalMapBits; // bit number of first bit in map record
357 totalMapBits += mapBits;
358
359 } while ( ((BTNodeDescriptor*)mapNode.buffer)->fLink != 0 );
360
361 if (DEBUG_BUILD && totalMapBits != CalcMapBits (btreePtr))
362 Panic ("ExtendBTree: totalMapBits != CalcMapBits");
363
364 /////////////////////// Extend LEOF If Necessary ////////////////////////////
365
366 minEOF = (u_int64_t)newTotalNodes * (u_int64_t)nodeSize;
367 if ( (u_int64_t)filePtr->fcbEOF < minEOF )
368 {
369 maxEOF = (u_int64_t)0x7fffffffLL * (u_int64_t)nodeSize;
370
371 err = btreePtr->setEndOfForkProc (btreePtr->fileRefNum, minEOF, maxEOF);
372 M_ExitOnError (err);
373 }
374
375
376 //////////////////// Calc New Total Number Of Nodes /////////////////////////
377
378 newTotalNodes = filePtr->fcbEOF / nodeSize; // hack!
379 // do we wish to perform any verification of newTotalNodes at this point?
380
381 btreePtr->totalNodes = newTotalNodes; // do we need to update freeNodes here too?
382
383
384 ////////////// Calculate Number Of New Map Nodes Required ///////////////////
385
386 newMapNodes = 0;
387 if (newTotalNodes > totalMapBits)
388 {
389 newMapNodes = (((newTotalNodes - totalMapBits) >> 3) / mapNodeRecSize) + 1;
390 firstNewMapNodeNum = oldTotalNodes;
391 lastNewMapNodeNum = firstNewMapNodeNum + newMapNodes - 1;
392 }
393 else
394 {
395 err = ReleaseNode (btreePtr, &mapNode);
396 M_ExitOnError (err);
397
398 goto Success;
399 }
400
401
402 /////////////////////// Initialize New Map Nodes ////////////////////////////
403 // XXXdbg - this is the correct place for this:
404 ModifyBlockStart(btreePtr->fileRefNum, &mapNode);
405
406 ((BTNodeDescriptor*)mapNode.buffer)->fLink = firstNewMapNodeNum;
407
408 nodeNum = firstNewMapNodeNum;
409 while (true)
410 {
411 err = GetNewNode (btreePtr, nodeNum, &newNode);
412 M_ExitOnError (err);
413
414 // XXXdbg
415 ModifyBlockStart(btreePtr->fileRefNum, &newNode);
416
417 ((NodeDescPtr)newNode.buffer)->numRecords = 1;
418 ((NodeDescPtr)newNode.buffer)->kind = kBTMapNode;
419
420 // set free space offset
421 *(u_int16_t *)((Ptr)newNode.buffer + nodeSize - 4) = nodeSize - 6;
422
423 if (nodeNum++ == lastNewMapNodeNum)
424 break;
425
426 ((BTNodeDescriptor*)newNode.buffer)->fLink = nodeNum; // point to next map node
427
428 err = UpdateNode (btreePtr, &newNode, 0, kLockTransaction);
429 M_ExitOnError (err);
430 }
431
432 err = UpdateNode (btreePtr, &newNode, 0, kLockTransaction);
433 M_ExitOnError (err);
434
435
436 ///////////////////// Mark New Map Nodes Allocated //////////////////////////
437
438 nodeNum = firstNewMapNodeNum;
439 do {
440 bitInRecord = nodeNum - recStartBit;
441
442 while (bitInRecord >= mapBits)
443 {
444 nextNodeNum = ((NodeDescPtr)mapNode.buffer)->fLink;
445 if ( nextNodeNum == 0)
446 {
447 err = fsBTNoMoreMapNodesErr;
448 goto ErrorExit;
449 }
450
451 err = UpdateNode (btreePtr, &mapNode, 0, kLockTransaction);
452 M_ExitOnError (err);
453
454 err = GetNode (btreePtr, nextNodeNum, 0, &mapNode);
455 M_ExitOnError (err);
456
457 // XXXdbg
458 ModifyBlockStart(btreePtr->fileRefNum, &mapNode);
459
460 mapIndex = 0;
461
462 mapStart = (u_int16_t *) GetRecordAddress (btreePtr, mapNode.buffer, mapIndex);
463 mapSize = GetRecordSize (btreePtr, mapNode.buffer, mapIndex);
464
465 if (DEBUG_BUILD && mapSize != M_MapRecordSize (btreePtr->nodeSize) )
466 {
467 Panic ("ExtendBTree: mapSize != M_MapRecordSize");
468 }
469
470 mapBits = mapSize << 3; // mapSize (in bytes) * 8
471 recStartBit = totalMapBits; // bit number of first bit in map record
472 totalMapBits += mapBits;
473
474 bitInRecord = nodeNum - recStartBit;
475 }
476
477 mapPos = mapStart + ((nodeNum - recStartBit) >> 4);
478 bitInWord = 15 - ((nodeNum - recStartBit) & 0x0000000F);
479
480 M_SWAP_BE16_SetBitNum (*mapPos, bitInWord);
481
482 ++nodeNum;
483
484 } while (nodeNum <= lastNewMapNodeNum);
485
486 err = UpdateNode (btreePtr, &mapNode, 0, kLockTransaction);
487 M_ExitOnError (err);
488
489
490 //////////////////////////////// Success ////////////////////////////////////
491
492 Success:
493
494 btreePtr->totalNodes = newTotalNodes;
495 btreePtr->freeNodes += (newTotalNodes - oldTotalNodes) - newMapNodes;
496
497 btreePtr->flags |= kBTHeaderDirty; //\80\80 how about a macro for this
498
499 /* Force the b-tree header changes to disk */
500 (void) UpdateHeader (btreePtr, true);
501
502 return noErr;
503
504
505 ////////////////////////////// Error Exit ///////////////////////////////////
506
507 ErrorExit:
508
509 (void) ReleaseNode (btreePtr, &mapNode);
510 (void) ReleaseNode (btreePtr, &newNode);
511
512 return err;
513 }
514
515
516
517 /*-------------------------------------------------------------------------------
518
519 Routine: GetMapNode - Get the next map node and pointer to the map record.
520
521 Function: Given a BlockDescriptor to a map node in nodePtr, GetMapNode releases
522 it and gets the next node. If nodePtr->buffer is nil, then the header
523 node is retrieved.
524
525
526 Input: btreePtr - pointer to control block for BTree file
527 nodePtr - pointer to a BlockDescriptor of a map node
528
529 Output: nodePtr - pointer to the BlockDescriptor for the next map node
530 mapPtr - pointer to the map record within the map node
531 mapSize - number of bytes in the map record
532
533 Result: noErr - success
534 fsBTNoMoreMapNodesErr - we've run out of map nodes
535 fsBTInvalidNodeErr - bad node, or not node type kMapNode
536 != noErr - failure
537 -------------------------------------------------------------------------------*/
538
539 static
540 OSStatus GetMapNode (BTreeControlBlockPtr btreePtr,
541 BlockDescriptor *nodePtr,
542 u_int16_t **mapPtr,
543 u_int16_t *mapSize )
544 {
545 OSStatus err;
546 u_int16_t mapIndex;
547 u_int32_t nextNodeNum;
548
549 if (nodePtr->buffer != nil) // if iterator is valid...
550 {
551 nextNodeNum = ((NodeDescPtr)nodePtr->buffer)->fLink;
552 if (nextNodeNum == 0)
553 {
554 err = fsBTNoMoreMapNodesErr;
555 goto ErrorExit;
556 }
557
558 err = ReleaseNode (btreePtr, nodePtr);
559 M_ExitOnError (err);
560
561 err = GetNode (btreePtr, nextNodeNum, 0, nodePtr);
562 M_ExitOnError (err);
563
564 if ( ((NodeDescPtr)nodePtr->buffer)->kind != kBTMapNode)
565 {
566 err = fsBTBadNodeType;
567 goto ErrorExit;
568 }
569
570 ++btreePtr->numMapNodesRead;
571 mapIndex = 0;
572 } else {
573 err = GetNode (btreePtr, kHeaderNodeNum, 0, nodePtr);
574 M_ExitOnError (err);
575
576 if ( ((NodeDescPtr)nodePtr->buffer)->kind != kBTHeaderNode)
577 {
578 err = fsBTInvalidHeaderErr; //\80\80 or fsBTBadNodeType
579 goto ErrorExit;
580 }
581
582 mapIndex = 2;
583 }
584
585
586 *mapPtr = (u_int16_t *) GetRecordAddress (btreePtr, nodePtr->buffer, mapIndex);
587 *mapSize = GetRecordSize (btreePtr, nodePtr->buffer, mapIndex);
588
589 return noErr;
590
591
592 ErrorExit:
593
594 (void) ReleaseNode (btreePtr, nodePtr);
595
596 *mapPtr = nil;
597 *mapSize = 0;
598
599 return err;
600 }
601
602
603
604 ////////////////////////////////// CalcMapBits //////////////////////////////////
605
606 u_int32_t CalcMapBits (BTreeControlBlockPtr btreePtr)
607 {
608 u_int32_t mapBits;
609
610 mapBits = M_HeaderMapRecordSize (btreePtr->nodeSize) << 3;
611
612 while (mapBits < btreePtr->totalNodes)
613 mapBits += M_MapRecordSize (btreePtr->nodeSize) << 3;
614
615 return mapBits;
616 }
617
618
619 /*-------------------------------------------------------------------------------
620 Routine: BTZeroUnusedNodes
621
622 Function: Write zeros to all nodes in the B-tree that are not currently in use.
623 -------------------------------------------------------------------------------*/
624 __private_extern__
625 int
626 BTZeroUnusedNodes(FCB *filePtr)
627 {
628 int err;
629 vnode_t vp;
630 BTreeControlBlockPtr btreePtr;
631 BlockDescriptor mapNode;
632 buf_t bp;
633 u_int32_t nodeNumber;
634 u_int16_t *mapPtr, *pos;
635 u_int16_t mapSize, size;
636 u_int16_t mask;
637 u_int16_t bitNumber;
638 u_int16_t word;
639 int numWritten;
640
641 vp = FTOV(filePtr);
642 btreePtr = (BTreeControlBlockPtr) filePtr->fcbBTCBPtr;
643 bp = NULL;
644 nodeNumber = 0;
645 mapNode.buffer = nil;
646 mapNode.blockHeader = nil;
647 numWritten = 0;
648
649 /* Iterate over map nodes. */
650 while (true)
651 {
652 err = GetMapNode (btreePtr, &mapNode, &mapPtr, &mapSize);
653 if (err)
654 {
655 err = MacToVFSError(err);
656 goto ErrorExit;
657 }
658
659 pos = mapPtr;
660 size = mapSize;
661 size >>= 1; /* convert to number of 16-bit words */
662
663 /* Iterate over 16-bit words in the map record. */
664 while (size--)
665 {
666 if (*pos != 0xFFFF) /* Anything free in this word? */
667 {
668 word = SWAP_BE16(*pos);
669
670 /* Iterate over bits in the word. */
671 for (bitNumber = 0, mask = 0x8000;
672 bitNumber < 16;
673 ++bitNumber, mask >>= 1)
674 {
675 if (word & mask)
676 continue; /* This node is in use. */
677
678 if (nodeNumber + bitNumber >= btreePtr->totalNodes)
679 {
680 /* We've processed all of the nodes. */
681 goto done;
682 }
683
684 /*
685 * Get a buffer full of zeros and write it to the unused
686 * node. Since we'll probably be writing a lot of nodes,
687 * bypass the journal (to avoid a transaction that's too
688 * big). Instead, this behaves more like clearing out
689 * nodes when extending a B-tree (eg., ClearBTNodes).
690 */
691 bp = buf_getblk(vp, nodeNumber + bitNumber, btreePtr->nodeSize, 0, 0, BLK_META);
692 if (bp == NULL)
693 {
694 printf("hfs: BTZeroUnusedNodes: unable to read node %u\n", nodeNumber + bitNumber);
695 err = EIO;
696 goto ErrorExit;
697 }
698
699 buf_clear(bp);
700 buf_markaged(bp);
701
702 /*
703 * Try not to hog the buffer cache. Wait for the write
704 * every 32 nodes.
705 */
706 ++numWritten;
707 if (numWritten % 32 == 0)
708 VNOP_BWRITE(bp);
709 else
710 buf_bawrite(bp);
711 }
712 }
713
714 /* Go to the next word in the bitmap */
715 ++pos;
716 nodeNumber += 16;
717 }
718 }
719
720 ErrorExit:
721 done:
722 (void) ReleaseNode(btreePtr, &mapNode);
723
724 return err;
725 }
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