+++ /dev/null
-/*
- * Copyright (c) 2000-2015 Apple Inc. All rights reserved.
- *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. The rights granted to you under the License
- * may not be used to create, or enable the creation or redistribution of,
- * unlawful or unlicensed copies of an Apple operating system, or to
- * circumvent, violate, or enable the circumvention or violation of, any
- * terms of an Apple operating system software license agreement.
- *
- * Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
- */
-
-
-#include "hfs.h"
-#include "hfs_format.h"
-#include "hfs_endian.h"
-
-#include "FileMgrInternal.h"
-#include "BTreesInternal.h"
-
-#include <sys/malloc.h>
-
-/*
-============================================================
-Public (Exported) Routines:
-============================================================
-
- ExtendFileC Allocate more space to a given file.
-
- CompareExtentKeys
- Compare two extents file keys (a search key and a trial
- key). Used by the BTree manager when searching for,
- adding, or deleting keys in the extents file of an HFS
- volume.
-
- CompareExtentKeysPlus
- Compare two extents file keys (a search key and a trial
- key). Used by the BTree manager when searching for,
- adding, or deleting keys in the extents file of an HFS+
- volume.
-
- MapFileBlockC Convert (map) an offset within a given file into a
- physical disk address.
-
- TruncateFileC Truncates the disk space allocated to a file. The file
- space is truncated to a specified new physical EOF, rounded
- up to the next allocation block boundry. There is an option
- to truncate to the end of the extent containing the new EOF.
-
- FlushExtentFile
- Flush the extents file for a given volume.
-
- SearchExtentFile
- Search the FCB and extents file for an extent record that
- contains a given file position (in bytes).
-
-
-============================================================
-Internal Routines:
-============================================================
- FindExtentRecord
- Search the extents BTree for a particular extent record.
- SearchExtentRecord
- Search a given extent record to see if it contains a given
- file position (in bytes). Used by SearchExtentFile.
- ReleaseExtents
- Deallocate all allocation blocks in all extents of an extent
- data record.
- TruncateExtents
- Deallocate blocks and delete extent records for all allocation
- blocks beyond a certain point in a file. The starting point
- must be the first file allocation block for some extent record
- for the file.
- DeallocateFork
- Deallocate all allocation blocks belonging to a given fork.
- UpdateExtentRecord
- If the extent record came from the extents file, write out
- the updated record; otherwise, copy the updated record into
- the FCB resident extent record. If the record has no extents,
- and was in the extents file, then delete the record instead.
-*/
-
-#if CONFIG_HFS_STD
-static const int64_t kTwoGigabytes = 0x80000000LL;
-#endif
-
-enum
-{
- kDataForkType = 0,
- kResourceForkType = 0xFF,
-
- kPreviousRecord = -1
-};
-
-
-#if CONFIG_HFS_STD
-static OSErr HFSPlusToHFSExtents(
- const HFSPlusExtentRecord oldExtents,
- HFSExtentRecord newExtents);
-#endif
-
-static OSErr FindExtentRecord(
- const ExtendedVCB *vcb,
- u_int8_t forkType,
- u_int32_t fileID,
- u_int32_t startBlock,
- Boolean allowPrevious,
- HFSPlusExtentKey *foundKey,
- HFSPlusExtentRecord foundData,
- u_int32_t *foundHint);
-
-static OSErr DeleteExtentRecord(
- const ExtendedVCB *vcb,
- u_int8_t forkType,
- u_int32_t fileID,
- u_int32_t startBlock);
-
-static OSErr CreateExtentRecord(
- ExtendedVCB *vcb,
- HFSPlusExtentKey *key,
- HFSPlusExtentRecord extents,
- u_int32_t *hint);
-
-
-static OSErr GetFCBExtentRecord(
- const FCB *fcb,
- HFSPlusExtentRecord extents);
-
-static OSErr SearchExtentRecord(
- ExtendedVCB *vcb,
- u_int32_t searchFABN,
- const HFSPlusExtentRecord extentData,
- u_int32_t extentDataStartFABN,
- u_int32_t *foundExtentDataOffset,
- u_int32_t *endingFABNPlusOne,
- Boolean *noMoreExtents);
-
-static OSErr ReleaseExtents(
- ExtendedVCB *vcb,
- const HFSPlusExtentRecord extentRecord,
- u_int32_t *numReleasedAllocationBlocks,
- Boolean *releasedLastExtent);
-
-static OSErr DeallocateFork(
- ExtendedVCB *vcb,
- HFSCatalogNodeID fileID,
- u_int8_t forkType,
- HFSPlusExtentRecord catalogExtents,
- Boolean * recordDeleted);
-
-static OSErr TruncateExtents(
- ExtendedVCB *vcb,
- u_int8_t forkType,
- u_int32_t fileID,
- u_int32_t startBlock,
- Boolean * recordDeleted);
-
-static OSErr UpdateExtentRecord (
- ExtendedVCB *vcb,
- FCB *fcb,
- int deleted,
- const HFSPlusExtentKey *extentFileKey,
- const HFSPlusExtentRecord extentData,
- u_int32_t extentBTreeHint);
-
-static Boolean ExtentsAreIntegral(
- const HFSPlusExtentRecord extentRecord,
- u_int32_t mask,
- u_int32_t *blocksChecked,
- Boolean *checkedLastExtent);
-
-//_________________________________________________________________________________
-//
-// Routine: FindExtentRecord
-//
-// Purpose: Search the extents BTree for an extent record matching the given
-// FileID, fork, and starting file allocation block number.
-//
-// Inputs:
-// vcb Volume to search
-// forkType 0 = data fork, -1 = resource fork
-// fileID File's FileID (CatalogNodeID)
-// startBlock Starting file allocation block number
-// allowPrevious If the desired record isn't found and this flag is set,
-// then see if the previous record belongs to the same fork.
-// If so, then return it.
-//
-// Outputs:
-// foundKey The key data for the record actually found
-// foundData The extent record actually found (NOTE: on an HFS volume, the
-// fourth entry will be zeroes.
-// foundHint The BTree hint to find the node again
-//_________________________________________________________________________________
-static OSErr FindExtentRecord(
- const ExtendedVCB *vcb,
- u_int8_t forkType,
- u_int32_t fileID,
- u_int32_t startBlock,
- Boolean allowPrevious,
- HFSPlusExtentKey *foundKey,
- HFSPlusExtentRecord foundData,
- u_int32_t *foundHint)
-{
- FCB * fcb;
- struct BTreeIterator *btIterator = NULL;
- FSBufferDescriptor btRecord;
- OSErr err;
- u_int16_t btRecordSize;
-
- err = noErr;
- if (foundHint)
- *foundHint = 0;
- fcb = GetFileControlBlock(vcb->extentsRefNum);
-
- btIterator = hfs_mallocz(sizeof(struct BTreeIterator));
-
- /* HFS Plus / HFSX */
- if (vcb->vcbSigWord != kHFSSigWord) {
- HFSPlusExtentKey * extentKeyPtr;
- HFSPlusExtentRecord extentData;
-
- extentKeyPtr = (HFSPlusExtentKey*) &btIterator->key;
- extentKeyPtr->keyLength = kHFSPlusExtentKeyMaximumLength;
- extentKeyPtr->forkType = forkType;
- extentKeyPtr->pad = 0;
- extentKeyPtr->fileID = fileID;
- extentKeyPtr->startBlock = startBlock;
-
- btRecord.bufferAddress = &extentData;
- btRecord.itemSize = sizeof(HFSPlusExtentRecord);
- btRecord.itemCount = 1;
-
- err = BTSearchRecord(fcb, btIterator, &btRecord, &btRecordSize, btIterator);
-
- if (err == btNotFound && allowPrevious) {
- err = BTIterateRecord(fcb, kBTreePrevRecord, btIterator, &btRecord, &btRecordSize);
-
- // A previous record may not exist, so just return btNotFound (like we would if
- // it was for the wrong file/fork).
- if (err == (OSErr) fsBTStartOfIterationErr) //¥¥ fsBTStartOfIterationErr is type unsigned long
- err = btNotFound;
-
- if (err == noErr) {
- // Found a previous record. Does it belong to the same fork of the same file?
- if (extentKeyPtr->fileID != fileID || extentKeyPtr->forkType != forkType)
- err = btNotFound;
- }
- }
-
- if (err == noErr) {
- // Copy the found key back for the caller
- if (foundKey)
- BlockMoveData(extentKeyPtr, foundKey, sizeof(HFSPlusExtentKey));
- // Copy the found data back for the caller
- BlockMoveData(&extentData, foundData, sizeof(HFSPlusExtentRecord));
- }
- }
-#if CONFIG_HFS_STD
- else {
- HFSExtentKey * extentKeyPtr;
- HFSExtentRecord extentData;
-
- extentKeyPtr = (HFSExtentKey*) &btIterator->key;
- extentKeyPtr->keyLength = kHFSExtentKeyMaximumLength;
- extentKeyPtr->forkType = forkType;
- extentKeyPtr->fileID = fileID;
- extentKeyPtr->startBlock = startBlock;
-
- btRecord.bufferAddress = &extentData;
- btRecord.itemSize = sizeof(HFSExtentRecord);
- btRecord.itemCount = 1;
-
- err = BTSearchRecord(fcb, btIterator, &btRecord, &btRecordSize, btIterator);
-
- if (err == btNotFound && allowPrevious) {
- err = BTIterateRecord(fcb, kBTreePrevRecord, btIterator, &btRecord, &btRecordSize);
-
- // A previous record may not exist, so just return btNotFound (like we would if
- // it was for the wrong file/fork).
- if (err == (OSErr) fsBTStartOfIterationErr) //¥¥ fsBTStartOfIterationErr is type unsigned long
- err = btNotFound;
-
- if (err == noErr) {
- // Found a previous record. Does it belong to the same fork of the same file?
- if (extentKeyPtr->fileID != fileID || extentKeyPtr->forkType != forkType)
- err = btNotFound;
- }
- }
-
- if (err == noErr) {
- u_int16_t i;
-
- // Copy the found key back for the caller
- if (foundKey) {
- foundKey->keyLength = kHFSPlusExtentKeyMaximumLength;
- foundKey->forkType = extentKeyPtr->forkType;
- foundKey->pad = 0;
- foundKey->fileID = extentKeyPtr->fileID;
- foundKey->startBlock = extentKeyPtr->startBlock;
- }
- // Copy the found data back for the caller
- foundData[0].startBlock = extentData[0].startBlock;
- foundData[0].blockCount = extentData[0].blockCount;
- foundData[1].startBlock = extentData[1].startBlock;
- foundData[1].blockCount = extentData[1].blockCount;
- foundData[2].startBlock = extentData[2].startBlock;
- foundData[2].blockCount = extentData[2].blockCount;
-
- for (i = 3; i < kHFSPlusExtentDensity; ++i)
- {
- foundData[i].startBlock = 0;
- foundData[i].blockCount = 0;
- }
- }
- }
-#endif
-
- if (foundHint)
- *foundHint = btIterator->hint.nodeNum;
-
- hfs_free(btIterator, sizeof(*btIterator));
- return err;
-}
-
-
-
-static OSErr CreateExtentRecord(
- ExtendedVCB *vcb,
- HFSPlusExtentKey *key,
- HFSPlusExtentRecord extents,
- u_int32_t *hint)
-{
- struct BTreeIterator *btIterator = NULL;
- FSBufferDescriptor btRecord;
- u_int16_t btRecordSize;
- int lockflags;
- OSErr err;
-
- err = noErr;
- *hint = 0;
-
- btIterator = hfs_mallocz(sizeof(struct BTreeIterator));
-
- /*
- * The lock taken by callers of ExtendFileC is speculative and
- * only occurs when the file already has overflow extents. So
- * We need to make sure we have the lock here. The extents
- * btree lock can be nested (its recursive) so we always take
- * it here.
- */
- lockflags = hfs_systemfile_lock(vcb, SFL_EXTENTS, HFS_EXCLUSIVE_LOCK);
-
- /* HFS+/HFSX */
- if (vcb->vcbSigWord != kHFSSigWord) {
- btRecordSize = sizeof(HFSPlusExtentRecord);
- btRecord.bufferAddress = extents;
- btRecord.itemSize = btRecordSize;
- btRecord.itemCount = 1;
-
- BlockMoveData(key, &btIterator->key, sizeof(HFSPlusExtentKey));
- }
-#if CONFIG_HFS_STD
- else {
- /* HFS Standard */
- HFSExtentKey * keyPtr;
- HFSExtentRecord data;
-
- btRecordSize = sizeof(HFSExtentRecord);
- btRecord.bufferAddress = &data;
- btRecord.itemSize = btRecordSize;
- btRecord.itemCount = 1;
-
- keyPtr = (HFSExtentKey*) &btIterator->key;
- keyPtr->keyLength = kHFSExtentKeyMaximumLength;
- keyPtr->forkType = key->forkType;
- keyPtr->fileID = key->fileID;
- keyPtr->startBlock = key->startBlock;
-
- err = HFSPlusToHFSExtents(extents, data);
- }
-#endif
-
- if (err == noErr)
- err = BTInsertRecord(GetFileControlBlock(vcb->extentsRefNum), btIterator, &btRecord, btRecordSize);
-
- if (err == noErr)
- *hint = btIterator->hint.nodeNum;
-
- (void) BTFlushPath(GetFileControlBlock(vcb->extentsRefNum));
-
- hfs_systemfile_unlock(vcb, lockflags);
-
- hfs_free(btIterator, sizeof(*btIterator));
- return err;
-}
-
-
-static OSErr DeleteExtentRecord(
- const ExtendedVCB *vcb,
- u_int8_t forkType,
- u_int32_t fileID,
- u_int32_t startBlock)
-{
- struct BTreeIterator *btIterator = NULL;
- OSErr err;
-
- err = noErr;
-
- btIterator = hfs_mallocz(sizeof(struct BTreeIterator));
-
- /* HFS+ / HFSX */
- if (vcb->vcbSigWord != kHFSSigWord) { // HFS Plus volume
- HFSPlusExtentKey * keyPtr;
-
- keyPtr = (HFSPlusExtentKey*) &btIterator->key;
- keyPtr->keyLength = kHFSPlusExtentKeyMaximumLength;
- keyPtr->forkType = forkType;
- keyPtr->pad = 0;
- keyPtr->fileID = fileID;
- keyPtr->startBlock = startBlock;
- }
-#if CONFIG_HFS_STD
- else {
- /* HFS standard */
- HFSExtentKey * keyPtr;
-
- keyPtr = (HFSExtentKey*) &btIterator->key;
- keyPtr->keyLength = kHFSExtentKeyMaximumLength;
- keyPtr->forkType = forkType;
- keyPtr->fileID = fileID;
- keyPtr->startBlock = startBlock;
- }
-#endif
-
- err = BTDeleteRecord(GetFileControlBlock(vcb->extentsRefNum), btIterator);
- (void) BTFlushPath(GetFileControlBlock(vcb->extentsRefNum));
-
-
- hfs_free(btIterator, sizeof(*btIterator));
- return err;
-}
-
-
-
-//_________________________________________________________________________________
-//
-// Routine: MapFileBlock
-//
-// Function: Maps a file position into a physical disk address.
-//
-//_________________________________________________________________________________
-
-OSErr MapFileBlockC (
- ExtendedVCB *vcb, // volume that file resides on
- FCB *fcb, // FCB of file
- size_t numberOfBytes, // number of contiguous bytes desired
- off_t offset, // starting offset within file (in bytes)
- daddr64_t *startSector, // first sector (NOT an allocation block)
- size_t *availableBytes) // number of contiguous bytes (up to numberOfBytes)
-{
- OSErr err;
- u_int32_t allocBlockSize; // Size of the volume's allocation block
- u_int32_t sectorSize;
- HFSPlusExtentKey foundKey;
- HFSPlusExtentRecord foundData;
- u_int32_t foundIndex;
- u_int32_t hint;
- u_int32_t firstFABN = 0; // file allocation block of first block in found extent
- u_int32_t nextFABN; // file allocation block of block after end of found extent
- off_t dataEnd; // (offset) end of range that is contiguous
- u_int32_t sectorsPerBlock; // Number of sectors per allocation block
- u_int32_t startBlock = 0; // volume allocation block corresponding to firstFABN
- daddr64_t temp;
- off_t tmpOff;
-
- allocBlockSize = vcb->blockSize;
- sectorSize = VCBTOHFS(vcb)->hfs_logical_block_size;
-
- err = SearchExtentFile(vcb, fcb, offset, &foundKey, foundData, &foundIndex, &hint, &nextFABN);
- if (err == noErr) {
- startBlock = foundData[foundIndex].startBlock;
- firstFABN = nextFABN - foundData[foundIndex].blockCount;
- }
-
- if (err != noErr)
- {
- return err;
- }
-
- //
- // Determine the end of the available space. It will either be the end of the extent,
- // or the file's PEOF, whichever is smaller.
- //
- dataEnd = (off_t)((off_t)(nextFABN) * (off_t)(allocBlockSize)); // Assume valid data through end of this extent
- if (((off_t)fcb->ff_blocks * (off_t)allocBlockSize) < dataEnd) // Is PEOF shorter?
- dataEnd = (off_t)fcb->ff_blocks * (off_t)allocBlockSize; // Yes, so only map up to PEOF
-
- // Compute the number of sectors in an allocation block
- sectorsPerBlock = allocBlockSize / sectorSize; // sectors per allocation block
-
- //
- // Compute the absolute sector number that contains the offset of the given file
- // offset in sectors from start of the extent +
- // offset in sectors from start of allocation block space
- //
- temp = (daddr64_t)((offset - (off_t)((off_t)(firstFABN) * (off_t)(allocBlockSize)))/sectorSize);
- temp += (daddr64_t)startBlock * (daddr64_t)sectorsPerBlock;
-
- /* Add in any volume offsets */
- if (vcb->vcbSigWord == kHFSPlusSigWord)
- temp += vcb->hfsPlusIOPosOffset / sectorSize;
- else
- temp += vcb->vcbAlBlSt;
-
- // Return the desired sector for file position "offset"
- *startSector = temp;
-
- //
- // Determine the number of contiguous bytes until the end of the extent
- // (or the amount they asked for, whichever comes first).
- //
- if (availableBytes)
- {
- tmpOff = dataEnd - offset;
- /*
- * Disallow negative runs.
- */
- if (tmpOff <= 0) {
- /* This shouldn't happen unless something is corrupt */
- hfs_corruption_debug("MapFileBlockC: tmpOff <= 0 (%lld)\n", tmpOff);
- return EINVAL;
- }
-
- if (tmpOff > (off_t)(numberOfBytes)) {
- *availableBytes = numberOfBytes; // more there than they asked for, so pin the output
- }
- else {
- *availableBytes = tmpOff;
- }
- }
-
- return noErr;
-}
-
-
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-// Routine: ReleaseExtents
-//
-// Function: Release the extents of a single extent data record.
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-
-static OSErr ReleaseExtents(
- ExtendedVCB *vcb,
- const HFSPlusExtentRecord extentRecord,
- u_int32_t *numReleasedAllocationBlocks,
- Boolean *releasedLastExtent)
-{
- u_int32_t extentIndex;
- u_int32_t numberOfExtents;
- OSErr err = noErr;
-
- *numReleasedAllocationBlocks = 0;
- *releasedLastExtent = false;
-
- if (vcb->vcbSigWord == kHFSPlusSigWord)
- numberOfExtents = kHFSPlusExtentDensity;
- else
- numberOfExtents = kHFSExtentDensity;
-
- for( extentIndex = 0; extentIndex < numberOfExtents; extentIndex++)
- {
- u_int32_t numAllocationBlocks;
-
- // Loop over the extent record and release the blocks associated with each extent.
-
- numAllocationBlocks = extentRecord[extentIndex].blockCount;
- if ( numAllocationBlocks == 0 )
- {
- *releasedLastExtent = true;
- break;
- }
-
- err = BlockDeallocate( vcb, extentRecord[extentIndex].startBlock, numAllocationBlocks , 0);
- if ( err != noErr )
- break;
-
- *numReleasedAllocationBlocks += numAllocationBlocks; // bump FABN to beg of next extent
- }
-
- return( err );
-}
-
-
-
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-// Routine: TruncateExtents
-//
-// Purpose: Delete extent records whose starting file allocation block number
-// is greater than or equal to a given starting block number. The
-// allocation blocks represented by the extents are deallocated.
-//
-// Inputs:
-// vcb Volume to operate on
-// fileID Which file to operate on
-// startBlock Starting file allocation block number for first extent
-// record to delete.
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-
-static OSErr TruncateExtents(
- ExtendedVCB *vcb,
- u_int8_t forkType,
- u_int32_t fileID,
- u_int32_t startBlock,
- Boolean * recordDeleted)
-{
- OSErr err;
- u_int32_t numberExtentsReleased;
- Boolean releasedLastExtent;
- u_int32_t hint;
- HFSPlusExtentKey key;
- HFSPlusExtentRecord extents;
- int lockflags;
-
- /*
- * The lock taken by callers of TruncateFileC is speculative and
- * only occurs when the file already has overflow extents. So
- * We need to make sure we have the lock here. The extents
- * btree lock can be nested (its recursive) so we always take
- * it here.
- */
- lockflags = hfs_systemfile_lock(vcb, SFL_EXTENTS, HFS_EXCLUSIVE_LOCK);
-
- while (true) {
- err = FindExtentRecord(vcb, forkType, fileID, startBlock, false, &key, extents, &hint);
- if (err != noErr) {
- if (err == btNotFound)
- err = noErr;
- break;
- }
-
- err = ReleaseExtents( vcb, extents, &numberExtentsReleased, &releasedLastExtent );
- if (err != noErr) break;
-
- err = DeleteExtentRecord(vcb, forkType, fileID, startBlock);
- if (err != noErr) break;
-
- *recordDeleted = true;
- startBlock += numberExtentsReleased;
- }
- hfs_systemfile_unlock(vcb, lockflags);
-
- return err;
-}
-
-
-
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-// Routine: DeallocateFork
-//
-// Function: De-allocates all disk space allocated to a specified fork.
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-
-static OSErr DeallocateFork(
- ExtendedVCB *vcb,
- HFSCatalogNodeID fileID,
- u_int8_t forkType,
- HFSPlusExtentRecord catalogExtents,
- Boolean * recordDeleted) /* true if a record was deleted */
-{
- OSErr err;
- u_int32_t numReleasedAllocationBlocks;
- Boolean releasedLastExtent;
-
- // Release the catalog extents
- err = ReleaseExtents( vcb, catalogExtents, &numReleasedAllocationBlocks, &releasedLastExtent );
- // Release the extra extents, if present
- if (err == noErr && !releasedLastExtent)
- err = TruncateExtents(vcb, forkType, fileID, numReleasedAllocationBlocks, recordDeleted);
-
- return( err );
-}
-
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-// Routine: FlushExtentFile
-//
-// Function: Flushes the extent file for a specified volume
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-
-OSErr FlushExtentFile( ExtendedVCB *vcb )
-{
- FCB * fcb;
- OSErr err;
- int lockflags;
-
- fcb = GetFileControlBlock(vcb->extentsRefNum);
-
- lockflags = hfs_systemfile_lock(vcb, SFL_EXTENTS, HFS_EXCLUSIVE_LOCK);
- err = BTFlushPath(fcb);
- hfs_systemfile_unlock(vcb, lockflags);
-
- if ( err == noErr )
- {
- // If the FCB for the extent "file" is dirty, mark the VCB as dirty.
-
- if (FTOC(fcb)->c_flag & C_MODIFIED)
- {
- MarkVCBDirty( vcb );
- // err = FlushVolumeControlBlock( vcb );
- }
- }
-
- return( err );
-}
-
-
-#if CONFIG_HFS_STD
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-// Routine: CompareExtentKeys
-//
-// Function: Compares two extent file keys (a search key and a trial key) for
-// an HFS volume.
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-
-int32_t CompareExtentKeys( const HFSExtentKey *searchKey, const HFSExtentKey *trialKey )
-{
- int32_t result; // ± 1
-
- #if DEBUG
- if (searchKey->keyLength != kHFSExtentKeyMaximumLength)
- DebugStr("HFS: search Key is wrong length");
- if (trialKey->keyLength != kHFSExtentKeyMaximumLength)
- DebugStr("HFS: trial Key is wrong length");
- #endif
-
- result = -1; // assume searchKey < trialKey
-
- if (searchKey->fileID == trialKey->fileID) {
- //
- // FileNum's are equal; compare fork types
- //
- if (searchKey->forkType == trialKey->forkType) {
- //
- // Fork types are equal; compare allocation block number
- //
- if (searchKey->startBlock == trialKey->startBlock) {
- //
- // Everything is equal
- //
- result = 0;
- }
- else {
- //
- // Allocation block numbers differ; determine sign
- //
- if (searchKey->startBlock > trialKey->startBlock)
- result = 1;
- }
- }
- else {
- //
- // Fork types differ; determine sign
- //
- if (searchKey->forkType > trialKey->forkType)
- result = 1;
- }
- }
- else {
- //
- // FileNums differ; determine sign
- //
- if (searchKey->fileID > trialKey->fileID)
- result = 1;
- }
-
- return( result );
-}
-#endif
-
-
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-// Routine: CompareExtentKeysPlus
-//
-// Function: Compares two extent file keys (a search key and a trial key) for
-// an HFS volume.
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-
-int32_t CompareExtentKeysPlus( const HFSPlusExtentKey *searchKey, const HFSPlusExtentKey *trialKey )
-{
- int32_t result; // ± 1
-
- #if DEBUG
- if (searchKey->keyLength != kHFSPlusExtentKeyMaximumLength)
- DebugStr("HFS: search Key is wrong length");
- if (trialKey->keyLength != kHFSPlusExtentKeyMaximumLength)
- DebugStr("HFS: trial Key is wrong length");
- #endif
-
- result = -1; // assume searchKey < trialKey
-
- if (searchKey->fileID == trialKey->fileID) {
- //
- // FileNum's are equal; compare fork types
- //
- if (searchKey->forkType == trialKey->forkType) {
- //
- // Fork types are equal; compare allocation block number
- //
- if (searchKey->startBlock == trialKey->startBlock) {
- //
- // Everything is equal
- //
- result = 0;
- }
- else {
- //
- // Allocation block numbers differ; determine sign
- //
- if (searchKey->startBlock > trialKey->startBlock)
- result = 1;
- }
- }
- else {
- //
- // Fork types differ; determine sign
- //
- if (searchKey->forkType > trialKey->forkType)
- result = 1;
- }
- }
- else {
- //
- // FileNums differ; determine sign
- //
- if (searchKey->fileID > trialKey->fileID)
- result = 1;
- }
-
- return( result );
-}
-
-static int
-should_pin_blocks(hfsmount_t *hfsmp, FCB *fcb)
-{
- if (!ISSET(hfsmp->hfs_flags, HFS_CS_HOTFILE_PIN)
- || fcb->ff_cp == NULL || fcb->ff_cp->c_vp == NULL) {
- return 0;
- }
-
- int pin_blocks;
-
- //
- // File system metadata should get pinned
- //
- if (vnode_issystem(fcb->ff_cp->c_vp)) {
- return 1;
- }
-
- //
- // If a file is AutoCandidate, we should not pin its blocks because
- // it was an automatically added file and this function is intended
- // to pin new blocks being added to user-generated content.
- //
- if (fcb->ff_cp->c_attr.ca_recflags & kHFSAutoCandidateMask) {
- return 0;
- }
-
- //
- // If a file is marked FastDevPinned it is an existing pinned file
- // or a new file that should be pinned.
- //
- // If a file is marked FastDevCandidate it is a new file that is
- // being written to for the first time so we don't want to pin it
- // just yet as it may not meet the criteria (i.e. too large).
- //
- if ((fcb->ff_cp->c_attr.ca_recflags & (kHFSFastDevPinnedMask)) != 0) {
- pin_blocks = 1;
- } else {
- pin_blocks = 0;
- }
-
- return pin_blocks;
-}
-
-
-
-static void
-pin_blocks_if_needed(ExtendedVCB *vcb, FCB *fcb, u_int32_t startBlock, u_int32_t blockCount)
-{
- if (!should_pin_blocks(vcb, fcb)) {
- return;
- }
-
- // ask CoreStorage to pin the new blocks being added to this file
- if (hfs_pin_block_range((struct hfsmount *)vcb, HFS_PIN_IT, startBlock, blockCount) == 0) {
- struct vnode *vp = fcb->ff_cp->c_vp;
-
- // and make sure to keep our accounting in order
- hfs_hotfile_adjust_blocks(vp, -blockCount);
- }
-}
-
-
-
-/*
- * Add a file extent to a file.
- *
- * Used by hfs_extendfs to extend the volume allocation bitmap file.
- *
- */
-int
-AddFileExtent(ExtendedVCB *vcb, FCB *fcb, u_int32_t startBlock, u_int32_t blockCount)
-{
- HFSPlusExtentKey foundKey;
- HFSPlusExtentRecord foundData;
- u_int32_t foundIndex;
- u_int32_t hint;
- u_int32_t nextBlock;
- int64_t peof;
- int i;
- int error;
-
- peof = (int64_t)(fcb->ff_blocks + blockCount) * (int64_t)vcb->blockSize;
-
- error = SearchExtentFile(vcb, fcb, peof-1, &foundKey, foundData, &foundIndex, &hint, &nextBlock);
- if (error != fxRangeErr)
- return (EBUSY);
-
- /*
- * Add new extent. See if there is room in the current record.
- */
- if (foundData[foundIndex].blockCount != 0)
- ++foundIndex;
- if (foundIndex == kHFSPlusExtentDensity) {
- /*
- * Existing record is full so create a new one.
- */
- foundKey.keyLength = kHFSPlusExtentKeyMaximumLength;
- foundKey.forkType = kDataForkType;
- foundKey.pad = 0;
- foundKey.fileID = FTOC(fcb)->c_fileid;
- foundKey.startBlock = nextBlock;
-
- foundData[0].startBlock = startBlock;
- foundData[0].blockCount = blockCount;
-
- /* zero out remaining extents. */
- for (i = 1; i < kHFSPlusExtentDensity; ++i) {
- foundData[i].startBlock = 0;
- foundData[i].blockCount = 0;
- }
-
- foundIndex = 0;
-
- error = CreateExtentRecord(vcb, &foundKey, foundData, &hint);
- if (error == fxOvFlErr) {
- error = dskFulErr;
- } else if (error == 0) {
- pin_blocks_if_needed(vcb, fcb, startBlock, blockCount);
- }
-
- } else {
- /*
- * Add a new extent into existing record.
- */
- foundData[foundIndex].startBlock = startBlock;
- foundData[foundIndex].blockCount = blockCount;
- error = UpdateExtentRecord(vcb, fcb, 0, &foundKey, foundData, hint);
- if (error == 0) {
- pin_blocks_if_needed(vcb, fcb, startBlock, blockCount);
- }
- }
- (void) FlushExtentFile(vcb);
-
- return (error);
-}
-
-
-//_________________________________________________________________________________
-//
-// Routine: Extendfile
-//
-// Function: Extends the disk space allocated to a file.
-//
-//_________________________________________________________________________________
-
-OSErr ExtendFileC (
- ExtendedVCB *vcb, // volume that file resides on
- FCB *fcb, // FCB of file to truncate
- int64_t bytesToAdd, // number of bytes to allocate
- u_int32_t blockHint, // desired starting allocation block
- u_int32_t flags, // EFContig and/or EFAll
- int64_t *actualBytesAdded) // number of bytes actually allocated
-{
- OSErr err;
- u_int32_t volumeBlockSize;
- int64_t blocksToAdd;
- int64_t bytesThisExtent;
- HFSPlusExtentKey foundKey;
- HFSPlusExtentRecord foundData;
- u_int32_t foundIndex;
- u_int32_t hint;
- u_int32_t nextBlock;
- u_int32_t startBlock;
- Boolean allOrNothing;
- Boolean forceContig;
- Boolean wantContig;
- Boolean useMetaZone;
- Boolean needsFlush;
- int allowFlushTxns;
- u_int32_t actualStartBlock;
- u_int32_t actualNumBlocks;
- u_int32_t numExtentsPerRecord;
- int64_t maximumBytes;
- int64_t availbytes;
- int64_t peof;
- u_int32_t prevblocks;
- uint32_t fastdev = 0;
-
- struct hfsmount *hfsmp = (struct hfsmount*)vcb;
- allowFlushTxns = 0;
- needsFlush = false;
- *actualBytesAdded = 0;
- volumeBlockSize = vcb->blockSize;
- allOrNothing = ((flags & kEFAllMask) != 0);
- forceContig = ((flags & kEFContigMask) != 0);
- prevblocks = fcb->ff_blocks;
-
- if (vcb->vcbSigWord != kHFSSigWord) {
- numExtentsPerRecord = kHFSPlusExtentDensity;
- }
-#if CONFIG_HFS_STD
- else {
- /* HFS Standard */
- numExtentsPerRecord = kHFSExtentDensity;
-
- /* Make sure the request and new PEOF are less than 2GB if HFS std*/
- if (bytesToAdd >= kTwoGigabytes)
- goto HFS_Std_Overflow;
- if ((((int64_t)fcb->ff_blocks * (int64_t)volumeBlockSize) + bytesToAdd) >= kTwoGigabytes)
- goto HFS_Std_Overflow;
- }
-#endif
-
- //
- // Determine how many blocks need to be allocated.
- // Round up the number of desired bytes to add.
- //
- blocksToAdd = howmany(bytesToAdd, volumeBlockSize);
- bytesToAdd = (int64_t)((int64_t)blocksToAdd * (int64_t)volumeBlockSize);
-
- /*
- * For deferred allocations just reserve the blocks.
- */
- if ((flags & kEFDeferMask)
- && (vcb->vcbSigWord == kHFSPlusSigWord)
- && (bytesToAdd < (int64_t)HFS_MAX_DEFERED_ALLOC)
- && (blocksToAdd < hfs_freeblks(VCBTOHFS(vcb), 1))) {
- hfs_lock_mount (hfsmp);
- vcb->loanedBlocks += blocksToAdd;
- hfs_unlock_mount(hfsmp);
-
- fcb->ff_unallocblocks += blocksToAdd;
- FTOC(fcb)->c_blocks += blocksToAdd;
- fcb->ff_blocks += blocksToAdd;
-
- /*
- * We haven't touched the disk here; no blocks have been
- * allocated and the volume will not be inconsistent if we
- * don't update the catalog record immediately.
- */
- FTOC(fcb)->c_flag |= C_MINOR_MOD;
- *actualBytesAdded = bytesToAdd;
- return (0);
- }
- /*
- * Give back any unallocated blocks before doing real allocations.
- */
- if (fcb->ff_unallocblocks > 0) {
- u_int32_t loanedBlocks;
-
- loanedBlocks = fcb->ff_unallocblocks;
- blocksToAdd += loanedBlocks;
- bytesToAdd = (int64_t)blocksToAdd * (int64_t)volumeBlockSize;
- FTOC(fcb)->c_blocks -= loanedBlocks;
- fcb->ff_blocks -= loanedBlocks;
- fcb->ff_unallocblocks = 0;
-
- hfs_lock_mount(hfsmp);
- vcb->loanedBlocks -= loanedBlocks;
- hfs_unlock_mount(hfsmp);
- }
-
- //
- // If the file's clump size is larger than the allocation block size,
- // then set the maximum number of bytes to the requested number of bytes
- // rounded up to a multiple of the clump size.
- //
- if ((vcb->vcbClpSiz > (int32_t)volumeBlockSize)
- && (bytesToAdd < (int64_t)HFS_MAX_DEFERED_ALLOC)
- && (flags & kEFNoClumpMask) == 0) {
- maximumBytes = (int64_t)howmany(bytesToAdd, vcb->vcbClpSiz);
- maximumBytes *= vcb->vcbClpSiz;
- } else {
- maximumBytes = bytesToAdd;
- }
-
-#if CONFIG_HFS_STD
- //
- // Compute new physical EOF, rounded up to a multiple of a block.
- //
- if ( (vcb->vcbSigWord == kHFSSigWord) && // Too big?
- ((((int64_t)fcb->ff_blocks * (int64_t)volumeBlockSize) + bytesToAdd) >= kTwoGigabytes) ) {
- if (allOrNothing) // Yes, must they have it all?
- goto HFS_Std_Overflow; // Yes, can't have it
- else {
- --blocksToAdd; // No, give give 'em one block less
- bytesToAdd -= volumeBlockSize;
- }
- }
-#endif
-
- //
- // If allocation is all-or-nothing, make sure there are
- // enough free blocks on the volume (quick test).
- //
- if (allOrNothing &&
- (blocksToAdd > hfs_freeblks(VCBTOHFS(vcb), flags & kEFReserveMask))) {
- err = dskFulErr;
- goto ErrorExit;
- }
-
- //
- // See if there are already enough blocks allocated to the file.
- //
- peof = ((int64_t)fcb->ff_blocks * (int64_t)volumeBlockSize) + bytesToAdd; // potential new PEOF
- err = SearchExtentFile(vcb, fcb, peof-1, &foundKey, foundData, &foundIndex, &hint, &nextBlock);
- if (err == noErr) {
- // Enough blocks are already allocated. Just update the FCB to reflect the new length.
- fcb->ff_blocks = peof / volumeBlockSize;
- FTOC(fcb)->c_blocks += (bytesToAdd / volumeBlockSize);
- FTOC(fcb)->c_flag |= C_MODIFIED;
- goto Exit;
- }
- if (err != fxRangeErr) // Any real error?
- goto ErrorExit; // Yes, so exit immediately
-
- //
- // Adjust the PEOF to the end of the last extent.
- //
- peof = (int64_t)((int64_t)nextBlock * (int64_t)volumeBlockSize); // currently allocated PEOF
- bytesThisExtent = (int64_t)(nextBlock - fcb->ff_blocks) * (int64_t)volumeBlockSize;
- if (bytesThisExtent != 0) {
- fcb->ff_blocks = nextBlock;
- FTOC(fcb)->c_blocks += (bytesThisExtent / volumeBlockSize);
- FTOC(fcb)->c_flag |= C_MODIFIED;
- bytesToAdd -= bytesThisExtent;
- }
-
- //
- // Allocate some more space.
- //
- // First try a contiguous allocation (of the whole amount).
- // If that fails, get whatever we can.
- // If forceContig, then take whatever we got
- // else, keep getting bits and pieces (non-contig)
-
- /*
- * Note that for sparse devices (like sparse bundle dmgs), we
- * should only be aggressive with re-using once-allocated pieces
- * if we're not dealing with system files. If we're trying to operate
- * on behalf of a system file, we need the maximum contiguous amount
- * possible. For non-system files we favor locality and fragmentation over
- * contiguity as it can result in fewer blocks being needed from the underlying
- * filesystem that the sparse image resides upon.
- */
- err = noErr;
- if ( (vcb->hfs_flags & HFS_HAS_SPARSE_DEVICE)
- && (fcb->ff_cp->c_fileid >= kHFSFirstUserCatalogNodeID)
- && (flags & kEFMetadataMask) == 0) {
- /*
- * We want locality over contiguity so by default we set wantContig to
- * false unless we hit one of the circumstances below.
- */
- wantContig = false;
- if (hfs_isrbtree_active(VCBTOHFS(vcb))) {
- /*
- * If the red-black tree is acive, we can always find a suitable contiguous
- * chunk. So if the user specifically requests contiguous files, we should
- * honor that no matter what kind of device it is.
- */
- if (forceContig) {
- wantContig = true;
- }
- }
- else {
- /*
- * If the red-black tree is not active, then only set wantContig to true
- * if we have never done a contig scan on the device, which would populate
- * the free extent cache. Note that the caller may explicitly unset the
- * DID_CONTIG_SCAN bit in order to force us to vend a contiguous extent here
- * if the caller wants to get a contiguous chunk.
- */
- if ((vcb->hfs_flags & HFS_DID_CONTIG_SCAN) == 0) {
- vcb->hfs_flags |= HFS_DID_CONTIG_SCAN;
- wantContig = true;
- }
- }
- }
- else {
- wantContig = true;
- }
-
- if (should_pin_blocks(hfsmp, fcb))
- fastdev = HFS_ALLOC_FAST_DEV;
-
- useMetaZone = flags & kEFMetadataMask;
- do {
- if (blockHint != 0)
- startBlock = blockHint;
- else
- startBlock = foundData[foundIndex].startBlock + foundData[foundIndex].blockCount;
-
- actualNumBlocks = 0;
- actualStartBlock = 0;
-
- /* Find number of free blocks based on reserved block flag option */
- availbytes = (int64_t)hfs_freeblks(VCBTOHFS(vcb), flags & kEFReserveMask) *
- (int64_t)volumeBlockSize;
- if (availbytes <= 0) {
- err = dskFulErr;
- } else {
- if (wantContig && (availbytes < bytesToAdd)) {
- err = dskFulErr;
- }
- else {
- uint32_t ba_flags = fastdev;
-
- if (wantContig) {
- ba_flags |= HFS_ALLOC_FORCECONTIG;
- }
- if (useMetaZone) {
- ba_flags |= HFS_ALLOC_METAZONE;
- }
- if (allowFlushTxns) {
- ba_flags |= HFS_ALLOC_FLUSHTXN;
- }
-
- err = BlockAllocate(
- vcb,
- startBlock,
- howmany(MIN(bytesToAdd, availbytes), volumeBlockSize),
- howmany(MIN(maximumBytes, availbytes), volumeBlockSize),
- ba_flags,
- &actualStartBlock,
- &actualNumBlocks);
- }
- }
- if (err == dskFulErr) {
- if (forceContig) {
- if (allowFlushTxns == 0) {
- /* If we're forcing contiguity, re-try but allow plucking from recently freed regions */
- allowFlushTxns = 1;
- wantContig = 1;
- err = noErr;
- continue;
- }
- else {
- break; // AllocContig failed because not enough contiguous space
- }
- }
- if (wantContig) {
- // Couldn't get one big chunk, so get whatever we can.
- err = noErr;
- wantContig = false;
- continue;
- }
- if (actualNumBlocks != 0)
- err = noErr;
-
- if (useMetaZone == 0) {
- /* Couldn't get anything so dip into metadat zone */
- err = noErr;
- useMetaZone = 1;
- continue;
- }
-
- /* If we couldn't find what we needed without flushing the journal, then go ahead and do it now */
- if (allowFlushTxns == 0) {
- allowFlushTxns = 1;
- err = noErr;
- continue;
- }
-
- }
- if (err == noErr) {
- // Add the new extent to the existing extent record, or create a new one.
- if ((actualStartBlock == startBlock) && (blockHint == 0)) {
- // We grew the file's last extent, so just adjust the number of blocks.
- foundData[foundIndex].blockCount += actualNumBlocks;
- err = UpdateExtentRecord(vcb, fcb, 0, &foundKey, foundData, hint);
- if (err != noErr) break;
- }
- else {
- u_int16_t i;
-
- // Need to add a new extent. See if there is room in the current record.
- if (foundData[foundIndex].blockCount != 0) // Is current extent free to use?
- ++foundIndex; // No, so use the next one.
- if (foundIndex == numExtentsPerRecord) {
- // This record is full. Need to create a new one.
- if (FTOC(fcb)->c_fileid == kHFSExtentsFileID) {
- (void) BlockDeallocate(vcb, actualStartBlock, actualNumBlocks, 0);
- err = dskFulErr; // Oops. Can't extend extents file past first record.
- break;
- }
-
- foundKey.keyLength = kHFSPlusExtentKeyMaximumLength;
- if (FORK_IS_RSRC(fcb))
- foundKey.forkType = kResourceForkType;
- else
- foundKey.forkType = kDataForkType;
- foundKey.pad = 0;
- foundKey.fileID = FTOC(fcb)->c_fileid;
- foundKey.startBlock = nextBlock;
-
- foundData[0].startBlock = actualStartBlock;
- foundData[0].blockCount = actualNumBlocks;
-
- // zero out remaining extents...
- for (i = 1; i < kHFSPlusExtentDensity; ++i)
- {
- foundData[i].startBlock = 0;
- foundData[i].blockCount = 0;
- }
-
- foundIndex = 0;
-
- err = CreateExtentRecord(vcb, &foundKey, foundData, &hint);
- if (err == fxOvFlErr) {
- // We couldn't create an extent record because extents B-tree
- // couldn't grow. Dellocate the extent just allocated and
- // return a disk full error.
- (void) BlockDeallocate(vcb, actualStartBlock, actualNumBlocks, 0);
- err = dskFulErr;
- }
- if (err != noErr) break;
-
- needsFlush = true; // We need to update the B-tree header
- }
- else {
- // Add a new extent into this record and update.
- foundData[foundIndex].startBlock = actualStartBlock;
- foundData[foundIndex].blockCount = actualNumBlocks;
- err = UpdateExtentRecord(vcb, fcb, 0, &foundKey, foundData, hint);
- if (err != noErr) break;
- }
- }
-
- // Figure out how many bytes were actually allocated.
- // NOTE: BlockAllocate could have allocated more than we asked for.
- // Don't set the PEOF beyond what our client asked for.
- nextBlock += actualNumBlocks;
- bytesThisExtent = (int64_t)((int64_t)actualNumBlocks * (int64_t)volumeBlockSize);
- if (bytesThisExtent > bytesToAdd) {
- bytesToAdd = 0;
- }
- else {
- bytesToAdd -= bytesThisExtent;
- maximumBytes -= bytesThisExtent;
- }
- fcb->ff_blocks += (bytesThisExtent / volumeBlockSize);
- FTOC(fcb)->c_blocks += (bytesThisExtent / volumeBlockSize);
- FTOC(fcb)->c_flag |= C_MODIFIED;
-
- // If contiguous allocation was requested, then we've already got one contiguous
- // chunk. If we didn't get all we wanted, then adjust the error to disk full.
- if (forceContig) {
- if (bytesToAdd != 0)
- err = dskFulErr;
- break; // We've already got everything that's contiguous
- }
- }
- } while (err == noErr && bytesToAdd);
-
-ErrorExit:
-Exit:
- if (VCBTOHFS(vcb)->hfs_flags & HFS_METADATA_ZONE) {
- /* Keep the roving allocator out of the metadata zone. */
- if (vcb->nextAllocation >= VCBTOHFS(vcb)->hfs_metazone_start &&
- vcb->nextAllocation <= VCBTOHFS(vcb)->hfs_metazone_end) {
- hfs_lock_mount (hfsmp);
- HFS_UPDATE_NEXT_ALLOCATION(vcb, VCBTOHFS(vcb)->hfs_metazone_end + 1);
- MarkVCBDirty(vcb);
- hfs_unlock_mount(hfsmp);
- }
- }
- if (prevblocks < fcb->ff_blocks) {
- *actualBytesAdded = (int64_t)(fcb->ff_blocks - prevblocks) * (int64_t)volumeBlockSize;
- } else {
- *actualBytesAdded = 0;
- }
-
- if (fastdev) {
- hfs_hotfile_adjust_blocks(fcb->ff_cp->c_vp,
- (int64_t)prevblocks - fcb->ff_blocks);
- }
-
- if (needsFlush)
- (void) FlushExtentFile(vcb);
-
- return err;
-
-#if CONFIG_HFS_STD
-HFS_Std_Overflow:
- err = fileBoundsErr;
- goto ErrorExit;
-#endif
-}
-
-
-
-//_________________________________________________________________________________
-//
-// Routine: TruncateFileC
-//
-// Function: Truncates the disk space allocated to a file. The file space is
-// truncated to a specified new PEOF rounded up to the next allocation
-// block boundry. If the 'TFTrunExt' option is specified, the file is
-// truncated to the end of the extent containing the new PEOF.
-//
-//_________________________________________________________________________________
-
-OSErr TruncateFileC (
- ExtendedVCB *vcb, // volume that file resides on
- FCB *fcb, // FCB of file to truncate
- int64_t peof, // new physical size for file
- int deleted, // if nonzero, the file's catalog record has already been deleted.
- int rsrc, // does this represent a resource fork or not?
- uint32_t fileid, // the fileid of the file we're manipulating.
- Boolean truncateToExtent) // if true, truncate to end of extent containing newPEOF
-
-{
- OSErr err;
- u_int32_t nextBlock; // next file allocation block to consider
- u_int32_t startBlock; // Physical (volume) allocation block number of start of a range
- u_int32_t physNumBlocks; // Number of allocation blocks in file (according to PEOF)
- u_int32_t numBlocks;
- HFSPlusExtentKey key; // key for current extent record; key->keyLength == 0 if FCB's extent record
- u_int32_t hint; // BTree hint corresponding to key
- HFSPlusExtentRecord extentRecord;
- u_int32_t extentIndex;
- u_int32_t extentNextBlock;
- u_int32_t numExtentsPerRecord;
- int64_t temp64;
- u_int8_t forkType;
- Boolean extentChanged; // true if we actually changed an extent
- Boolean recordDeleted; // true if an extent record got deleted
-
- recordDeleted = false;
-
- if (vcb->vcbSigWord == kHFSPlusSigWord) {
- numExtentsPerRecord = kHFSPlusExtentDensity;
- }
- else {
- numExtentsPerRecord = kHFSExtentDensity;
- }
-
- if (rsrc) {
- forkType = kResourceForkType;
- }
- else {
- forkType = kDataForkType;
- }
-
- temp64 = fcb->ff_blocks;
- physNumBlocks = (u_int32_t)temp64;
-
- //
- // Round newPEOF up to a multiple of the allocation block size. If new size is
- // two gigabytes or more, then round down by one allocation block (??? really?
- // shouldn't that be an error?).
- //
- nextBlock = howmany(peof, vcb->blockSize); // number of allocation blocks to remain in file
- peof = (int64_t)((int64_t)nextBlock * (int64_t)vcb->blockSize); // number of bytes in those blocks
-
-#if CONFIG_HFS_STD
- if ((vcb->vcbSigWord == kHFSSigWord) && (peof >= kTwoGigabytes)) {
- #if DEBUG
- DebugStr("HFS: Trying to truncate a file to 2GB or more");
- #endif
- err = fileBoundsErr;
- goto ErrorExit;
- }
-#endif
-
- //
- // Update FCB's length
- //
- /*
- * XXX Any errors could cause ff_blocks and c_blocks to get out of sync...
- */
- numBlocks = peof / vcb->blockSize;
- if (!deleted) {
- FTOC(fcb)->c_blocks -= (fcb->ff_blocks - numBlocks);
- }
- fcb->ff_blocks = numBlocks;
-
- // this catalog entry is modified and *must* get forced
- // to disk when hfs_update() is called
- if (!deleted) {
- /*
- * If the file is already C_NOEXISTS, then the catalog record
- * has been removed from disk already. We wouldn't need to force
- * another update
- */
- FTOC(fcb)->c_flag |= C_MODIFIED;
- }
- //
- // If the new PEOF is 0, then truncateToExtent has no meaning (we should always deallocate
- // all storage).
- //
- if (peof == 0) {
- int i;
-
- // Deallocate all the extents for this fork
- err = DeallocateFork(vcb, fileid, forkType, fcb->fcbExtents, &recordDeleted);
- if (err != noErr) goto ErrorExit; // got some error, so return it
-
- // Update the catalog extent record (making sure it's zeroed out)
- if (err == noErr) {
- for (i=0; i < kHFSPlusExtentDensity; i++) {
- fcb->fcbExtents[i].startBlock = 0;
- fcb->fcbExtents[i].blockCount = 0;
- }
- }
- goto Done;
- }
-
- //
- // Find the extent containing byte (peof-1). This is the last extent we'll keep.
- // (If truncateToExtent is true, we'll keep the whole extent; otherwise, we'll only
- // keep up through peof). The search will tell us how many allocation blocks exist
- // in the found extent plus all previous extents.
- //
- err = SearchExtentFile(vcb, fcb, peof-1, &key, extentRecord, &extentIndex, &hint, &extentNextBlock);
- if (err != noErr) goto ErrorExit;
-
- extentChanged = false; // haven't changed the extent yet
-
- if (!truncateToExtent) {
- //
- // Shorten this extent. It may be the case that the entire extent gets
- // freed here.
- //
- numBlocks = extentNextBlock - nextBlock; // How many blocks in this extent to free up
- if (numBlocks != 0) {
- // Compute first volume allocation block to free
- startBlock = extentRecord[extentIndex].startBlock + extentRecord[extentIndex].blockCount - numBlocks;
- // Free the blocks in bitmap
- err = BlockDeallocate(vcb, startBlock, numBlocks, 0);
- if (err != noErr) goto ErrorExit;
- // Adjust length of this extent
- extentRecord[extentIndex].blockCount -= numBlocks;
- // If extent is empty, set start block to 0
- if (extentRecord[extentIndex].blockCount == 0)
- extentRecord[extentIndex].startBlock = 0;
- // Remember that we changed the extent record
- extentChanged = true;
- }
- }
-
- //
- // Now move to the next extent in the record, and set up the file allocation block number
- //
- nextBlock = extentNextBlock; // Next file allocation block to free
- ++extentIndex; // Its index within the extent record
-
- //
- // Release all following extents in this extent record. Update the record.
- //
- while (extentIndex < numExtentsPerRecord && extentRecord[extentIndex].blockCount != 0) {
- numBlocks = extentRecord[extentIndex].blockCount;
- // Deallocate this extent
- err = BlockDeallocate(vcb, extentRecord[extentIndex].startBlock, numBlocks, 0);
- if (err != noErr) goto ErrorExit;
- // Update next file allocation block number
- nextBlock += numBlocks;
- // Zero out start and length of this extent to delete it from record
- extentRecord[extentIndex].startBlock = 0;
- extentRecord[extentIndex].blockCount = 0;
- // Remember that we changed an extent
- extentChanged = true;
- // Move to next extent in record
- ++extentIndex;
- }
-
- //
- // If any of the extents in the current record were changed, then update that
- // record (in the FCB, or extents file).
- //
- if (extentChanged) {
- err = UpdateExtentRecord(vcb, fcb, deleted, &key, extentRecord, hint);
- if (err != noErr) goto ErrorExit;
- }
-
- //
- // If there are any following allocation blocks, then we need
- // to seach for their extent records and delete those allocation
- // blocks.
- //
- if (nextBlock < physNumBlocks)
- err = TruncateExtents(vcb, forkType, fileid, nextBlock, &recordDeleted);
-
-Done:
-ErrorExit:
- if (recordDeleted)
- (void) FlushExtentFile(vcb);
-
- return err;
-}
-
-
-/*
- * HFS Plus only
- *
- */
-OSErr HeadTruncateFile (
- ExtendedVCB *vcb,
- FCB *fcb,
- u_int32_t headblks)
-{
- HFSPlusExtentRecord extents;
- HFSPlusExtentRecord tailExtents;
- HFSCatalogNodeID fileID;
- u_int8_t forkType;
- u_int32_t blkcnt = 0;
- u_int32_t startblk;
- u_int32_t blksfreed;
- int i, j;
- int error = 0;
- int lockflags;
-
-
- if (vcb->vcbSigWord != kHFSPlusSigWord)
- return (-1);
-
- forkType = FORK_IS_RSRC(fcb) ? kResourceForkType : kDataForkType;
- fileID = FTOC(fcb)->c_fileid;
- bzero(tailExtents, sizeof(tailExtents));
-
- blksfreed = 0;
- startblk = 0;
-
- /*
- * Process catalog resident extents
- */
- for (i = 0, j = 0; i < kHFSPlusExtentDensity; ++i) {
- blkcnt = fcb->fcbExtents[i].blockCount;
- if (blkcnt == 0)
- break; /* end of extents */
-
- if (blksfreed < headblks) {
- error = BlockDeallocate(vcb, fcb->fcbExtents[i].startBlock, blkcnt, 0);
- /*
- * Any errors after the first BlockDeallocate
- * must be ignored so we can put the file in
- * a known state.
- */
- if (error ) {
- if (i == 0)
- goto ErrorExit; /* uh oh */
- else {
- error = 0;
- printf("hfs: HeadTruncateFile: problems deallocating %s (%d)\n",
- FTOC(fcb)->c_desc.cd_nameptr ? (const char *)FTOC(fcb)->c_desc.cd_nameptr : "", error);
- }
- }
-
- blksfreed += blkcnt;
- fcb->fcbExtents[i].startBlock = 0;
- fcb->fcbExtents[i].blockCount = 0;
- } else {
- tailExtents[j].startBlock = fcb->fcbExtents[i].startBlock;
- tailExtents[j].blockCount = blkcnt;
- ++j;
- }
- startblk += blkcnt;
- }
-
- if (blkcnt == 0)
- goto CopyExtents;
-
- lockflags = hfs_systemfile_lock(vcb, SFL_EXTENTS, HFS_EXCLUSIVE_LOCK);
-
- /*
- * Process overflow extents
- */
- for (;;) {
- u_int32_t extblks;
-
- error = FindExtentRecord(vcb, forkType, fileID, startblk, false, NULL, extents, NULL);
- if (error) {
- /*
- * Any errors after the first BlockDeallocate
- * must be ignored so we can put the file in
- * a known state.
- */
- if (error != btNotFound)
- printf("hfs: HeadTruncateFile: problems finding extents %s (%d)\n",
- FTOC(fcb)->c_desc.cd_nameptr ? (const char *)FTOC(fcb)->c_desc.cd_nameptr : "", error);
- error = 0;
- break;
- }
-
- for(i = 0, extblks = 0; i < kHFSPlusExtentDensity; ++i) {
- blkcnt = extents[i].blockCount;
- if (blkcnt == 0)
- break; /* end of extents */
-
- if (blksfreed < headblks) {
- error = BlockDeallocate(vcb, extents[i].startBlock, blkcnt, 0);
- if (error) {
- printf("hfs: HeadTruncateFile: problems deallocating %s (%d)\n",
- FTOC(fcb)->c_desc.cd_nameptr ? (const char *)FTOC(fcb)->c_desc.cd_nameptr : "", error);
- error = 0;
- }
- blksfreed += blkcnt;
- } else {
- tailExtents[j].startBlock = extents[i].startBlock;
- tailExtents[j].blockCount = blkcnt;
- ++j;
- }
- extblks += blkcnt;
- }
-
- error = DeleteExtentRecord(vcb, forkType, fileID, startblk);
- if (error) {
- printf("hfs: HeadTruncateFile: problems deallocating %s (%d)\n",
- FTOC(fcb)->c_desc.cd_nameptr ? (const char *)FTOC(fcb)->c_desc.cd_nameptr : "", error);
- error = 0;
- }
-
- if (blkcnt == 0)
- break; /* all done */
-
- startblk += extblks;
- }
- hfs_systemfile_unlock(vcb, lockflags);
-
-CopyExtents:
- if (blksfreed) {
- bcopy(tailExtents, fcb->fcbExtents, sizeof(tailExtents));
- blkcnt = fcb->ff_blocks - headblks;
- FTOC(fcb)->c_blocks -= headblks;
- fcb->ff_blocks = blkcnt;
-
- FTOC(fcb)->c_flag |= C_MODIFIED;
- FTOC(fcb)->c_touch_chgtime = TRUE;
-
- (void) FlushExtentFile(vcb);
- }
-
-ErrorExit:
- return MacToVFSError(error);
-}
-
-
-
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-// Routine: SearchExtentRecord (was XRSearch)
-//
-// Function: Searches extent record for the extent mapping a given file
-// allocation block number (FABN).
-//
-// Input: searchFABN - desired FABN
-// extentData - pointer to extent data record (xdr)
-// extentDataStartFABN - beginning FABN for extent record
-//
-// Output: foundExtentDataOffset - offset to extent entry within xdr
-// result = noErr, offset to extent mapping desired FABN
-// result = FXRangeErr, offset to last extent in record
-// endingFABNPlusOne - ending FABN +1
-// noMoreExtents - True if the extent was not found, and the
-// extent record was not full (so don't bother
-// looking in subsequent records); false otherwise.
-//
-// Result: noErr = ok
-// FXRangeErr = desired FABN > last mapped FABN in record
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-
-static OSErr SearchExtentRecord(
- ExtendedVCB *vcb,
- u_int32_t searchFABN,
- const HFSPlusExtentRecord extentData,
- u_int32_t extentDataStartFABN,
- u_int32_t *foundExtentIndex,
- u_int32_t *endingFABNPlusOne,
- Boolean *noMoreExtents)
-{
- OSErr err = noErr;
- u_int32_t extentIndex;
- /* Set it to the HFS std value */
- u_int32_t numberOfExtents = kHFSExtentDensity;
- u_int32_t numAllocationBlocks;
- Boolean foundExtent;
-
- *endingFABNPlusOne = extentDataStartFABN;
- *noMoreExtents = false;
- foundExtent = false;
-
- /* Override numberOfExtents for HFS+/HFSX */
- if (vcb->vcbSigWord != kHFSSigWord) {
- numberOfExtents = kHFSPlusExtentDensity;
- }
-
- for( extentIndex = 0; extentIndex < numberOfExtents; ++extentIndex )
- {
-
- // Loop over the extent record and find the search FABN.
-
- numAllocationBlocks = extentData[extentIndex].blockCount;
- if ( numAllocationBlocks == 0 )
- {
- break;
- }
-
- *endingFABNPlusOne += numAllocationBlocks;
-
- if( searchFABN < *endingFABNPlusOne )
- {
- // Found the extent.
- foundExtent = true;
- break;
- }
- }
-
- if( foundExtent )
- {
- // Found the extent. Note the extent offset
- *foundExtentIndex = extentIndex;
- }
- else
- {
- // Did not find the extent. Set foundExtentDataOffset accordingly
- if( extentIndex > 0 )
- {
- *foundExtentIndex = extentIndex - 1;
- }
- else
- {
- *foundExtentIndex = 0;
- }
-
- // If we found an empty extent, then set noMoreExtents.
- if (extentIndex < numberOfExtents)
- *noMoreExtents = true;
-
- // Finally, return an error to the caller
- err = fxRangeErr;
- }
-
- return( err );
-}
-
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-// Routine: SearchExtentFile (was XFSearch)
-//
-// Function: Searches extent file (including the FCB resident extent record)
-// for the extent mapping a given file position.
-//
-// Input: vcb - VCB pointer
-// fcb - FCB pointer
-// filePosition - file position (byte address)
-//
-// Output: foundExtentKey - extent key record (xkr)
-// If extent was found in the FCB's resident extent record,
-// then foundExtentKey->keyLength will be set to 0.
-// foundExtentData - extent data record(xdr)
-// foundExtentIndex - index to extent entry in xdr
-// result = 0, offset to extent mapping desired FABN
-// result = FXRangeErr, offset to last extent in record
-// (i.e., kNumExtentsPerRecord-1)
-// extentBTreeHint - BTree hint for extent record
-// kNoHint = Resident extent record
-// endingFABNPlusOne - ending FABN +1
-//
-// Result:
-// noErr Found an extent that contains the given file position
-// FXRangeErr Given position is beyond the last allocated extent
-// (other) (some other internal I/O error)
-//\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b\8b
-
-OSErr SearchExtentFile(
- ExtendedVCB *vcb,
- const FCB *fcb,
- int64_t filePosition,
- HFSPlusExtentKey *foundExtentKey,
- HFSPlusExtentRecord foundExtentData,
- u_int32_t *foundExtentIndex,
- u_int32_t *extentBTreeHint,
- u_int32_t *endingFABNPlusOne )
-{
- OSErr err;
- u_int32_t filePositionBlock;
- int64_t temp64;
- Boolean noMoreExtents;
- int lockflags;
-
- temp64 = filePosition / (int64_t)vcb->blockSize;
- filePositionBlock = (u_int32_t)temp64;
-
- bcopy ( fcb->fcbExtents, foundExtentData, sizeof(HFSPlusExtentRecord));
-
- // Search the resident FCB first.
- err = SearchExtentRecord( vcb, filePositionBlock, foundExtentData, 0,
- foundExtentIndex, endingFABNPlusOne, &noMoreExtents );
-
- if( err == noErr ) {
- // Found the extent. Set results accordingly
- *extentBTreeHint = kNoHint; // no hint, because not in the BTree
- foundExtentKey->keyLength = 0; // 0 = the FCB itself
-
- goto Exit;
- }
-
- // Didn't find extent in FCB. If FCB's extent record wasn't full, there's no point
- // in searching the extents file. Note that SearchExtentRecord left us pointing at
- // the last valid extent (or the first one, if none were valid). This means we need
- // to fill in the hint and key outputs, just like the "if" statement above.
- if ( noMoreExtents ) {
- *extentBTreeHint = kNoHint; // no hint, because not in the BTree
- foundExtentKey->keyLength = 0; // 0 = the FCB itself
- err = fxRangeErr; // There are no more extents, so must be beyond PEOF
- goto Exit;
- }
-
- //
- // Find the desired record, or the previous record if it is the same fork
- //
- lockflags = hfs_systemfile_lock(vcb, SFL_EXTENTS, HFS_EXCLUSIVE_LOCK);
-
- err = FindExtentRecord(vcb, FORK_IS_RSRC(fcb) ? kResourceForkType : kDataForkType,
- FTOC(fcb)->c_fileid, filePositionBlock, true, foundExtentKey, foundExtentData, extentBTreeHint);
- hfs_systemfile_unlock(vcb, lockflags);
-
- if (err == btNotFound) {
- //
- // If we get here, the desired position is beyond the extents in the FCB, and there are no extents
- // in the extents file. Return the FCB's extents and a range error.
- //
- *extentBTreeHint = kNoHint;
- foundExtentKey->keyLength = 0;
- err = GetFCBExtentRecord(fcb, foundExtentData);
- // Note: foundExtentIndex and endingFABNPlusOne have already been set as a result of the very
- // first SearchExtentRecord call in this function (when searching in the FCB's extents, and
- // we got a range error).
-
- return fxRangeErr;
- }
-
- //
- // If we get here, there was either a BTree error, or we found an appropriate record.
- // If we found a record, then search it for the correct index into the extents.
- //
- if (err == noErr) {
- // Find appropriate index into extent record
- err = SearchExtentRecord(vcb, filePositionBlock, foundExtentData, foundExtentKey->startBlock,
- foundExtentIndex, endingFABNPlusOne, &noMoreExtents);
- }
-
-Exit:
- return err;
-}
-
-
-
-//============================================================================
-// Routine: UpdateExtentRecord
-//
-// Function: Write new extent data to an existing extent record with a given key.
-// If all of the extents are empty, and the extent record is in the
-// extents file, then the record is deleted.
-//
-// Input: vcb - the volume containing the extents
-// fcb - the file that owns the extents
-// deleted - whether or not the file is already deleted
-// extentFileKey - pointer to extent key record (xkr)
-// If the key length is 0, then the extents are actually part
-// of the catalog record, stored in the FCB.
-// extentData - pointer to extent data record (xdr)
-// extentBTreeHint - hint for given key, or kNoHint
-//
-// Result: noErr = ok
-// (other) = error from BTree
-//============================================================================
-
-static OSErr UpdateExtentRecord (ExtendedVCB *vcb, FCB *fcb, int deleted,
- const HFSPlusExtentKey *extentFileKey,
- const HFSPlusExtentRecord extentData,
- u_int32_t extentBTreeHint)
-{
- OSErr err = noErr;
-
- if (extentFileKey->keyLength == 0) { // keyLength == 0 means the FCB's extent record
- BlockMoveData(extentData, fcb->fcbExtents, sizeof(HFSPlusExtentRecord));
- if (!deleted) {
- FTOC(fcb)->c_flag |= C_MODIFIED;
- }
- }
- else {
- struct BTreeIterator *btIterator = NULL;
- FSBufferDescriptor btRecord;
- u_int16_t btRecordSize;
- FCB * btFCB;
- int lockflags;
-
- //
- // Need to find and change a record in Extents BTree
- //
- btFCB = GetFileControlBlock(vcb->extentsRefNum);
-
- btIterator = hfs_mallocz(sizeof(struct BTreeIterator));
-
- /*
- * The lock taken by callers of ExtendFileC/TruncateFileC is
- * speculative and only occurs when the file already has
- * overflow extents. So we need to make sure we have the lock
- * here. The extents btree lock can be nested (its recursive)
- * so we always take it here.
- */
- lockflags = hfs_systemfile_lock(vcb, SFL_EXTENTS, HFS_EXCLUSIVE_LOCK);
-
- /* HFS+/HFSX */
- if (vcb->vcbSigWord != kHFSSigWord) { // HFS Plus volume
- HFSPlusExtentRecord foundData; // The extent data actually found
-
- BlockMoveData(extentFileKey, &btIterator->key, sizeof(HFSPlusExtentKey));
-
- btIterator->hint.index = 0;
- btIterator->hint.nodeNum = extentBTreeHint;
-
- btRecord.bufferAddress = &foundData;
- btRecord.itemSize = sizeof(HFSPlusExtentRecord);
- btRecord.itemCount = 1;
-
- err = BTSearchRecord(btFCB, btIterator, &btRecord, &btRecordSize, btIterator);
-
- if (err == noErr) {
- BlockMoveData(extentData, &foundData, sizeof(HFSPlusExtentRecord));
- err = BTReplaceRecord(btFCB, btIterator, &btRecord, btRecordSize);
- }
- (void) BTFlushPath(btFCB);
- }
-#if CONFIG_HFS_STD
- else {
- /* HFS Standard */
- HFSExtentKey * key; // Actual extent key used on disk in HFS
- HFSExtentRecord foundData; // The extent data actually found
-
- key = (HFSExtentKey*) &btIterator->key;
- key->keyLength = kHFSExtentKeyMaximumLength;
- key->forkType = extentFileKey->forkType;
- key->fileID = extentFileKey->fileID;
- key->startBlock = extentFileKey->startBlock;
-
- btIterator->hint.index = 0;
- btIterator->hint.nodeNum = extentBTreeHint;
-
- btRecord.bufferAddress = &foundData;
- btRecord.itemSize = sizeof(HFSExtentRecord);
- btRecord.itemCount = 1;
-
- err = BTSearchRecord(btFCB, btIterator, &btRecord, &btRecordSize, btIterator);
-
- if (err == noErr)
- err = HFSPlusToHFSExtents(extentData, (HFSExtentDescriptor *)&foundData);
-
- if (err == noErr)
- err = BTReplaceRecord(btFCB, btIterator, &btRecord, btRecordSize);
- (void) BTFlushPath(btFCB);
-
- }
-#endif
-
- hfs_systemfile_unlock(vcb, lockflags);
-
- hfs_free(btIterator, sizeof(*btIterator));
- }
-
- return err;
-}
-
-
-
-#if CONFIG_HFS_STD
-static OSErr HFSPlusToHFSExtents(
- const HFSPlusExtentRecord oldExtents,
- HFSExtentRecord newExtents)
-{
- OSErr err;
-
- err = noErr;
-
- // copy the first 3 extents
- newExtents[0].startBlock = oldExtents[0].startBlock;
- newExtents[0].blockCount = oldExtents[0].blockCount;
- newExtents[1].startBlock = oldExtents[1].startBlock;
- newExtents[1].blockCount = oldExtents[1].blockCount;
- newExtents[2].startBlock = oldExtents[2].startBlock;
- newExtents[2].blockCount = oldExtents[2].blockCount;
-
- #if DEBUG
- if (oldExtents[3].startBlock || oldExtents[3].blockCount) {
- DebugStr("ExtentRecord with > 3 extents is invalid for HFS");
- err = fsDSIntErr;
- }
- #endif
-
- return err;
-}
-#endif
-
-
-
-static OSErr GetFCBExtentRecord(
- const FCB *fcb,
- HFSPlusExtentRecord extents)
-{
-
- BlockMoveData(fcb->fcbExtents, extents, sizeof(HFSPlusExtentRecord));
-
- return noErr;
-}
-
-
-//_________________________________________________________________________________
-//
-// Routine: ExtentsAreIntegral
-//
-// Purpose: Ensure that each extent can hold an integral number of nodes
-// Called by the NodesAreContiguous function
-//_________________________________________________________________________________
-
-static Boolean ExtentsAreIntegral(
- const HFSPlusExtentRecord extentRecord,
- u_int32_t mask,
- u_int32_t *blocksChecked,
- Boolean *checkedLastExtent)
-{
- u_int32_t blocks;
- u_int32_t extentIndex;
-
- *blocksChecked = 0;
- *checkedLastExtent = false;
-
- for(extentIndex = 0; extentIndex < kHFSPlusExtentDensity; extentIndex++)
- {
- blocks = extentRecord[extentIndex].blockCount;
-
- if ( blocks == 0 )
- {
- *checkedLastExtent = true;
- break;
- }
-
- *blocksChecked += blocks;
-
- if (blocks & mask)
- return false;
- }
-
- return true;
-}
-
-
-//_________________________________________________________________________________
-//
-// Routine: NodesAreContiguous
-//
-// Purpose: Ensure that all b-tree nodes are contiguous on disk
-// Called by BTOpenPath during volume mount
-//_________________________________________________________________________________
-
-Boolean NodesAreContiguous(
- ExtendedVCB *vcb,
- FCB *fcb,
- u_int32_t nodeSize)
-{
- u_int32_t mask;
- u_int32_t startBlock;
- u_int32_t blocksChecked;
- u_int32_t hint;
- HFSPlusExtentKey key;
- HFSPlusExtentRecord extents;
- OSErr result;
- Boolean lastExtentReached;
- int lockflags;
-
-
- if (vcb->blockSize >= nodeSize)
- return TRUE;
-
- mask = (nodeSize / vcb->blockSize) - 1;
-
- // check the local extents
- (void) GetFCBExtentRecord(fcb, extents);
- if ( !ExtentsAreIntegral(extents, mask, &blocksChecked, &lastExtentReached) )
- return FALSE;
-
- if ( lastExtentReached ||
- (int64_t)((int64_t)blocksChecked * (int64_t)vcb->blockSize) >= (int64_t)fcb->ff_size)
- return TRUE;
-
- startBlock = blocksChecked;
-
- lockflags = hfs_systemfile_lock(vcb, SFL_EXTENTS, HFS_EXCLUSIVE_LOCK);
-
- // check the overflow extents (if any)
- while ( !lastExtentReached )
- {
- result = FindExtentRecord(vcb, kDataForkType, fcb->ff_cp->c_fileid, startBlock, FALSE, &key, extents, &hint);
- if (result) break;
-
- if ( !ExtentsAreIntegral(extents, mask, &blocksChecked, &lastExtentReached) ) {
- hfs_systemfile_unlock(vcb, lockflags);
- return FALSE;
- }
- startBlock += blocksChecked;
- }
- hfs_systemfile_unlock(vcb, lockflags);
- return TRUE;
-}
-
projects / apple / hfs.git / blobdiff