+
+static int yaffs_FindBlockForGarbageCollection(yaffs_Device * dev,
+ int aggressive)
+{
+
+ int b = dev->currentDirtyChecker;
+
+ int i;
+ int iterations;
+ int dirtiest = -1;
+ int pagesInUse = 0;
+ int prioritised=0;
+ yaffs_BlockInfo *bi;
+ int pendingPrioritisedExist = 0;
+
+ /* First let's see if we need to grab a prioritised block */
+ if(dev->hasPendingPrioritisedGCs){
+ for(i = dev->internalStartBlock; i < dev->internalEndBlock && !prioritised; i++){
+
+ bi = yaffs_GetBlockInfo(dev, i);
+ //yaffs_VerifyBlock(dev,bi,i);
+
+ if(bi->gcPrioritise) {
+ pendingPrioritisedExist = 1;
+ if(bi->blockState == YAFFS_BLOCK_STATE_FULL &&
+ yaffs_BlockNotDisqualifiedFromGC(dev, bi)){
+ pagesInUse = (bi->pagesInUse - bi->softDeletions);
+ dirtiest = i;
+ prioritised = 1;
+ aggressive = 1; /* Fool the non-aggressive skip logiv below */
+ }
+ }
+ }
+
+ if(!pendingPrioritisedExist) /* None found, so we can clear this */
+ dev->hasPendingPrioritisedGCs = 0;
+ }
+
+ /* If we're doing aggressive GC then we are happy to take a less-dirty block, and
+ * search harder.
+ * else (we're doing a leasurely gc), then we only bother to do this if the
+ * block has only a few pages in use.
+ */
+
+ dev->nonAggressiveSkip--;
+
+ if (!aggressive && (dev->nonAggressiveSkip > 0)) {
+ return -1;
+ }
+
+ if(!prioritised)
+ pagesInUse =
+ (aggressive) ? dev->nChunksPerBlock : YAFFS_PASSIVE_GC_CHUNKS + 1;
+
+ if (aggressive) {
+ iterations =
+ dev->internalEndBlock - dev->internalStartBlock + 1;
+ } else {
+ iterations =
+ dev->internalEndBlock - dev->internalStartBlock + 1;
+ iterations = iterations / 16;
+ if (iterations > 200) {
+ iterations = 200;
+ }
+ }
+
+ for (i = 0; i <= iterations && pagesInUse > 0 && !prioritised; i++) {
+ b++;
+ if (b < dev->internalStartBlock || b > dev->internalEndBlock) {
+ b = dev->internalStartBlock;
+ }
+
+ if (b < dev->internalStartBlock || b > dev->internalEndBlock) {
+ T(YAFFS_TRACE_ERROR,
+ (TSTR("**>> Block %d is not valid" TENDSTR), b));
+ YBUG();
+ }
+
+ bi = yaffs_GetBlockInfo(dev, b);
+
+#if 0
+ if (bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT) {
+ dirtiest = b;
+ pagesInUse = 0;
+ }
+ else
+#endif
+
+ if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
+ (bi->pagesInUse - bi->softDeletions) < pagesInUse &&
+ yaffs_BlockNotDisqualifiedFromGC(dev, bi)) {
+ dirtiest = b;
+ pagesInUse = (bi->pagesInUse - bi->softDeletions);
+ }
+ }
+
+ dev->currentDirtyChecker = b;
+
+ if (dirtiest > 0) {
+ T(YAFFS_TRACE_GC,
+ (TSTR("GC Selected block %d with %d free, prioritised:%d" TENDSTR), dirtiest,
+ dev->nChunksPerBlock - pagesInUse,prioritised));
+ }
+
+ dev->oldestDirtySequence = 0;
+
+ if (dirtiest > 0) {
+ dev->nonAggressiveSkip = 4;
+ }
+
+ return dirtiest;
+}
+
+static void yaffs_BlockBecameDirty(yaffs_Device * dev, int blockNo)
+{
+ yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockNo);
+
+ int erasedOk = 0;
+
+ /* If the block is still healthy erase it and mark as clean.
+ * If the block has had a data failure, then retire it.
+ */
+
+ T(YAFFS_TRACE_GC | YAFFS_TRACE_ERASE,
+ (TSTR("yaffs_BlockBecameDirty block %d state %d %s"TENDSTR),
+ blockNo, bi->blockState, (bi->needsRetiring) ? "needs retiring" : ""));
+
+ bi->blockState = YAFFS_BLOCK_STATE_DIRTY;
+
+ if (!bi->needsRetiring) {
+ yaffs_InvalidateCheckpoint(dev);
+ erasedOk = yaffs_EraseBlockInNAND(dev, blockNo);
+ if (!erasedOk) {
+ dev->nErasureFailures++;
+ T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
+ (TSTR("**>> Erasure failed %d" TENDSTR), blockNo));
+ }
+ }
+
+ if (erasedOk &&
+ ((yaffs_traceMask & YAFFS_TRACE_ERASE) || !yaffs_SkipVerification(dev))) {
+ int i;
+ for (i = 0; i < dev->nChunksPerBlock; i++) {
+ if (!yaffs_CheckChunkErased
+ (dev, blockNo * dev->nChunksPerBlock + i)) {
+ T(YAFFS_TRACE_ERROR,
+ (TSTR
+ (">>Block %d erasure supposedly OK, but chunk %d not erased"
+ TENDSTR), blockNo, i));
+ }
+ }
+ }
+
+ if (erasedOk) {
+ /* Clean it up... */
+ bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
+ dev->nErasedBlocks++;
+ bi->pagesInUse = 0;
+ bi->softDeletions = 0;
+ bi->hasShrinkHeader = 0;
+ bi->skipErasedCheck = 1; /* This is clean, so no need to check */
+ bi->gcPrioritise = 0;
+ yaffs_ClearChunkBits(dev, blockNo);
+
+ T(YAFFS_TRACE_ERASE,
+ (TSTR("Erased block %d" TENDSTR), blockNo));
+ } else {
+ dev->nFreeChunks -= dev->nChunksPerBlock; /* We lost a block of free space */
+
+ yaffs_RetireBlock(dev, blockNo);
+ T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
+ (TSTR("**>> Block %d retired" TENDSTR), blockNo));
+ }
+}
+
+static int yaffs_FindBlockForAllocation(yaffs_Device * dev)
+{
+ int i;
+
+ yaffs_BlockInfo *bi;
+
+ if (dev->nErasedBlocks < 1) {
+ /* Hoosterman we've got a problem.
+ * Can't get space to gc
+ */
+ T(YAFFS_TRACE_ERROR,
+ (TSTR("yaffs tragedy: no more eraased blocks" TENDSTR)));
+
+ return -1;
+ }
+
+ /* Find an empty block. */
+
+ for (i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
+ dev->allocationBlockFinder++;
+ if (dev->allocationBlockFinder < dev->internalStartBlock
+ || dev->allocationBlockFinder > dev->internalEndBlock) {
+ dev->allocationBlockFinder = dev->internalStartBlock;
+ }
+
+ bi = yaffs_GetBlockInfo(dev, dev->allocationBlockFinder);
+
+ if (bi->blockState == YAFFS_BLOCK_STATE_EMPTY) {
+ bi->blockState = YAFFS_BLOCK_STATE_ALLOCATING;
+ dev->sequenceNumber++;
+ bi->sequenceNumber = dev->sequenceNumber;
+ dev->nErasedBlocks--;
+ T(YAFFS_TRACE_ALLOCATE,
+ (TSTR("Allocated block %d, seq %d, %d left" TENDSTR),
+ dev->allocationBlockFinder, dev->sequenceNumber,
+ dev->nErasedBlocks));
+ return dev->allocationBlockFinder;
+ }
+ }
+
+ T(YAFFS_TRACE_ALWAYS,
+ (TSTR
+ ("yaffs tragedy: no more eraased blocks, but there should have been %d"
+ TENDSTR), dev->nErasedBlocks));
+
+ return -1;
+}
+
+
+
+static int yaffs_CalcCheckpointBlocksRequired(yaffs_Device *dev)
+{
+ if(!dev->nCheckpointBlocksRequired){
+ /* Not a valid value so recalculate */
+ int nBytes = 0;
+ int nBlocks;
+ int devBlocks = (dev->endBlock - dev->startBlock + 1);
+ int tnodeSize;
+
+ tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
+
+ if(tnodeSize < sizeof(yaffs_Tnode))
+ tnodeSize = sizeof(yaffs_Tnode);
+
+ nBytes += sizeof(yaffs_CheckpointValidity);
+ nBytes += sizeof(yaffs_CheckpointDevice);
+ nBytes += devBlocks * sizeof(yaffs_BlockInfo);
+ nBytes += devBlocks * dev->chunkBitmapStride;
+ nBytes += (sizeof(yaffs_CheckpointObject) + sizeof(__u32)) * (dev->nObjectsCreated - dev->nFreeObjects);
+ nBytes += (tnodeSize + sizeof(__u32)) * (dev->nTnodesCreated - dev->nFreeTnodes);
+ nBytes += sizeof(yaffs_CheckpointValidity);
+ nBytes += sizeof(__u32); /* checksum*/
+
+ /* Round up and add 2 blocks to allow for some bad blocks, so add 3 */
+
+ nBlocks = (nBytes/(dev->nDataBytesPerChunk * dev->nChunksPerBlock)) + 3;
+
+ dev->nCheckpointBlocksRequired = nBlocks;
+ }
+
+ return dev->nCheckpointBlocksRequired;
+}
+
+// Check if there's space to allocate...
+// Thinks.... do we need top make this ths same as yaffs_GetFreeChunks()?
+static int yaffs_CheckSpaceForAllocation(yaffs_Device * dev)
+{
+ int reservedChunks;
+ int reservedBlocks = dev->nReservedBlocks;
+ int checkpointBlocks;
+
+ checkpointBlocks = yaffs_CalcCheckpointBlocksRequired(dev) - dev->blocksInCheckpoint;
+ if(checkpointBlocks < 0)
+ checkpointBlocks = 0;
+
+ reservedChunks = ((reservedBlocks + checkpointBlocks) * dev->nChunksPerBlock);
+
+ return (dev->nFreeChunks > reservedChunks);
+}
+
+static int yaffs_AllocateChunk(yaffs_Device * dev, int useReserve, yaffs_BlockInfo **blockUsedPtr)
+{
+ int retVal;
+ yaffs_BlockInfo *bi;
+
+ if (dev->allocationBlock < 0) {
+ /* Get next block to allocate off */
+ dev->allocationBlock = yaffs_FindBlockForAllocation(dev);
+ dev->allocationPage = 0;
+ }
+
+ if (!useReserve && !yaffs_CheckSpaceForAllocation(dev)) {
+ /* Not enough space to allocate unless we're allowed to use the reserve. */
+ return -1;
+ }
+
+ if (dev->nErasedBlocks < dev->nReservedBlocks
+ && dev->allocationPage == 0) {
+ T(YAFFS_TRACE_ALLOCATE, (TSTR("Allocating reserve" TENDSTR)));
+ }
+
+ /* Next page please.... */
+ if (dev->allocationBlock >= 0) {
+ bi = yaffs_GetBlockInfo(dev, dev->allocationBlock);
+
+ retVal = (dev->allocationBlock * dev->nChunksPerBlock) +
+ dev->allocationPage;
+ bi->pagesInUse++;
+ yaffs_SetChunkBit(dev, dev->allocationBlock,
+ dev->allocationPage);
+
+ dev->allocationPage++;
+
+ dev->nFreeChunks--;
+
+ /* If the block is full set the state to full */
+ if (dev->allocationPage >= dev->nChunksPerBlock) {
+ bi->blockState = YAFFS_BLOCK_STATE_FULL;
+ dev->allocationBlock = -1;
+ }
+
+ if(blockUsedPtr)
+ *blockUsedPtr = bi;
+
+ return retVal;
+ }
+
+ T(YAFFS_TRACE_ERROR,
+ (TSTR("!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!" TENDSTR)));
+
+ return -1;
+}
+
+static int yaffs_GetErasedChunks(yaffs_Device * dev)
+{
+ int n;
+
+ n = dev->nErasedBlocks * dev->nChunksPerBlock;
+
+ if (dev->allocationBlock > 0) {
+ n += (dev->nChunksPerBlock - dev->allocationPage);
+ }
+
+ return n;
+
+}
+
+static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
+{
+ int oldChunk;
+ int newChunk;
+ int chunkInBlock;
+ int markNAND;
+ int retVal = YAFFS_OK;
+ int cleanups = 0;
+ int i;
+ int isCheckpointBlock;
+ int matchingChunk;
+
+ int chunksBefore = yaffs_GetErasedChunks(dev);
+ int chunksAfter;
+
+ yaffs_ExtendedTags tags;
+
+ yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, block);
+
+ yaffs_Object *object;
+
+ isCheckpointBlock = (bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT);
+
+ bi->blockState = YAFFS_BLOCK_STATE_COLLECTING;
+
+ T(YAFFS_TRACE_TRACING,
+ (TSTR("Collecting block %d, in use %d, shrink %d, " TENDSTR), block,
+ bi->pagesInUse, bi->hasShrinkHeader));
+
+ /*yaffs_VerifyFreeChunks(dev); */
+
+ bi->hasShrinkHeader = 0; /* clear the flag so that the block can erase */
+
+ /* Take off the number of soft deleted entries because
+ * they're going to get really deleted during GC.
+ */
+ dev->nFreeChunks -= bi->softDeletions;
+
+ dev->isDoingGC = 1;
+
+ if (isCheckpointBlock ||
+ !yaffs_StillSomeChunkBits(dev, block)) {
+ T(YAFFS_TRACE_TRACING,
+ (TSTR
+ ("Collecting block %d that has no chunks in use" TENDSTR),
+ block));
+ yaffs_BlockBecameDirty(dev, block);
+ } else {
+
+ __u8 *buffer = yaffs_GetTempBuffer(dev, __LINE__);
+
+ yaffs_VerifyBlock(dev,bi,block);
+
+ for (chunkInBlock = 0, oldChunk = block * dev->nChunksPerBlock;
+ chunkInBlock < dev->nChunksPerBlock
+ && yaffs_StillSomeChunkBits(dev, block);
+ chunkInBlock++, oldChunk++) {
+ if (yaffs_CheckChunkBit(dev, block, chunkInBlock)) {
+
+ /* This page is in use and might need to be copied off */
+
+ markNAND = 1;
+
+ yaffs_InitialiseTags(&tags);
+
+ yaffs_ReadChunkWithTagsFromNAND(dev, oldChunk,
+ buffer, &tags);
+
+ object =
+ yaffs_FindObjectByNumber(dev,
+ tags.objectId);
+
+ T(YAFFS_TRACE_GC_DETAIL,
+ (TSTR
+ ("Collecting page %d, %d %d %d " TENDSTR),
+ chunkInBlock, tags.objectId, tags.chunkId,
+ tags.byteCount));
+
+ if(object && !yaffs_SkipVerification(dev)){
+ if(tags.chunkId == 0)
+ matchingChunk = object->chunkId;
+ else if(object->softDeleted)
+ matchingChunk = oldChunk; /* Defeat the test */
+ else
+ matchingChunk = yaffs_FindChunkInFile(object,tags.chunkId,NULL);
+
+ if(oldChunk != matchingChunk)
+ T(YAFFS_TRACE_ERROR,
+ (TSTR("gc: page in gc mismatch: %d %d %d %d"TENDSTR),
+ oldChunk,matchingChunk,tags.objectId, tags.chunkId));
+
+ }
+
+ if (!object) {
+ T(YAFFS_TRACE_ERROR,
+ (TSTR
+ ("page %d in gc has no object: %d %d %d "
+ TENDSTR), oldChunk,
+ tags.objectId, tags.chunkId, tags.byteCount));
+ }
+
+ if (object && object->deleted
+ && tags.chunkId != 0) {
+ /* Data chunk in a deleted file, throw it away
+ * It's a soft deleted data chunk,
+ * No need to copy this, just forget about it and
+ * fix up the object.
+ */
+
+ object->nDataChunks--;
+
+ if (object->nDataChunks <= 0) {
+ /* remeber to clean up the object */
+ dev->gcCleanupList[cleanups] =
+ tags.objectId;
+ cleanups++;
+ }
+ markNAND = 0;
+ } else if (0
+ /* Todo object && object->deleted && object->nDataChunks == 0 */
+ ) {
+ /* Deleted object header with no data chunks.
+ * Can be discarded and the file deleted.
+ */
+ object->chunkId = 0;
+ yaffs_FreeTnode(object->myDev,
+ object->variant.
+ fileVariant.top);
+ object->variant.fileVariant.top = NULL;
+ yaffs_DoGenericObjectDeletion(object);
+
+ } else if (object) {
+ /* It's either a data chunk in a live file or
+ * an ObjectHeader, so we're interested in it.
+ * NB Need to keep the ObjectHeaders of deleted files
+ * until the whole file has been deleted off
+ */
+ tags.serialNumber++;
+
+ dev->nGCCopies++;
+
+ if (tags.chunkId == 0) {
+ /* It is an object Id,
+ * We need to nuke the shrinkheader flags first
+ * We no longer want the shrinkHeader flag since its work is done
+ * and if it is left in place it will mess up scanning.
+ * Also, clear out any shadowing stuff
+ */
+
+ yaffs_ObjectHeader *oh;
+ oh = (yaffs_ObjectHeader *)buffer;
+ oh->isShrink = 0;
+ oh->shadowsObject = oh->inbandShadowsObject = -1;
+ tags.extraShadows = 0;
+ tags.extraIsShrinkHeader = 0;
+
+ yaffs_VerifyObjectHeader(object,oh,&tags,1);
+ }
+
+ newChunk =
+ yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &tags, 1);
+
+ if (newChunk < 0) {
+ retVal = YAFFS_FAIL;
+ } else {
+
+ /* Ok, now fix up the Tnodes etc. */
+
+ if (tags.chunkId == 0) {
+ /* It's a header */
+ object->chunkId = newChunk;
+ object->serial = tags.serialNumber;
+ } else {
+ /* It's a data chunk */
+ yaffs_PutChunkIntoFile
+ (object,
+ tags.chunkId,
+ newChunk, 0);
+ }
+ }
+ }
+
+ yaffs_DeleteChunk(dev, oldChunk, markNAND, __LINE__);
+
+ }
+ }
+
+ yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
+
+
+ /* Do any required cleanups */
+ for (i = 0; i < cleanups; i++) {
+ /* Time to delete the file too */
+ object =
+ yaffs_FindObjectByNumber(dev,
+ dev->gcCleanupList[i]);
+ if (object) {
+ yaffs_FreeTnode(dev,
+ object->variant.fileVariant.
+ top);
+ object->variant.fileVariant.top = NULL;
+ T(YAFFS_TRACE_GC,
+ (TSTR
+ ("yaffs: About to finally delete object %d"
+ TENDSTR), object->objectId));
+ yaffs_DoGenericObjectDeletion(object);
+ object->myDev->nDeletedFiles--;
+ }
+
+ }
+
+ }
+
+ yaffs_VerifyCollectedBlock(dev,bi,block);
+
+ if (chunksBefore >= (chunksAfter = yaffs_GetErasedChunks(dev))) {
+ T(YAFFS_TRACE_GC,
+ (TSTR
+ ("gc did not increase free chunks before %d after %d"
+ TENDSTR), chunksBefore, chunksAfter));
+ }
+
+ dev->isDoingGC = 0;
+
+ return YAFFS_OK;
+}
+
+/* New garbage collector
+ * If we're very low on erased blocks then we do aggressive garbage collection
+ * otherwise we do "leasurely" garbage collection.
+ * Aggressive gc looks further (whole array) and will accept less dirty blocks.
+ * Passive gc only inspects smaller areas and will only accept more dirty blocks.
+ *
+ * The idea is to help clear out space in a more spread-out manner.
+ * Dunno if it really does anything useful.
+ */
+static int yaffs_CheckGarbageCollection(yaffs_Device * dev)
+{
+ int block;
+ int aggressive;
+ int gcOk = YAFFS_OK;
+ int maxTries = 0;
+
+ int checkpointBlockAdjust;
+
+ if (dev->isDoingGC) {
+ /* Bail out so we don't get recursive gc */
+ return YAFFS_OK;
+ }
+
+ /* This loop should pass the first time.
+ * We'll only see looping here if the erase of the collected block fails.
+ */
+
+ do {
+ maxTries++;
+
+ checkpointBlockAdjust = yaffs_CalcCheckpointBlocksRequired(dev) - dev->blocksInCheckpoint;
+ if(checkpointBlockAdjust < 0)
+ checkpointBlockAdjust = 0;
+
+ if (dev->nErasedBlocks < (dev->nReservedBlocks + checkpointBlockAdjust + 2)) {
+ /* We need a block soon...*/
+ aggressive = 1;
+ } else {
+ /* We're in no hurry */
+ aggressive = 0;
+ }
+
+ block = yaffs_FindBlockForGarbageCollection(dev, aggressive);
+
+ if (block > 0) {
+ dev->garbageCollections++;
+ if (!aggressive) {
+ dev->passiveGarbageCollections++;
+ }
+
+ T(YAFFS_TRACE_GC,
+ (TSTR
+ ("yaffs: GC erasedBlocks %d aggressive %d" TENDSTR),
+ dev->nErasedBlocks, aggressive));
+
+ gcOk = yaffs_GarbageCollectBlock(dev, block);
+ }
+
+ if (dev->nErasedBlocks < (dev->nReservedBlocks) && block > 0) {
+ T(YAFFS_TRACE_GC,
+ (TSTR
+ ("yaffs: GC !!!no reclaim!!! erasedBlocks %d after try %d block %d"
+ TENDSTR), dev->nErasedBlocks, maxTries, block));
+ }
+ } while ((dev->nErasedBlocks < dev->nReservedBlocks) && (block > 0)
+ && (maxTries < 2));
+
+ return aggressive ? gcOk : YAFFS_OK;
+}
+
+/*------------------------- TAGS --------------------------------*/
+
+static int yaffs_TagsMatch(const yaffs_ExtendedTags * tags, int objectId,
+ int chunkInObject)
+{
+ return (tags->chunkId == chunkInObject &&
+ tags->objectId == objectId && !tags->chunkDeleted) ? 1 : 0;
+
+}
+
+
+/*-------------------- Data file manipulation -----------------*/
+
+static int yaffs_FindChunkInFile(yaffs_Object * in, int chunkInInode,
+ yaffs_ExtendedTags * tags)
+{
+ /*Get the Tnode, then get the level 0 offset chunk offset */
+ yaffs_Tnode *tn;
+ int theChunk = -1;
+ yaffs_ExtendedTags localTags;
+ int retVal = -1;
+
+ yaffs_Device *dev = in->myDev;
+
+ if (!tags) {
+ /* Passed a NULL, so use our own tags space */
+ tags = &localTags;
+ }
+
+ tn = yaffs_FindLevel0Tnode(dev, &in->variant.fileVariant, chunkInInode);
+
+ if (tn) {
+ theChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
+
+ retVal =
+ yaffs_FindChunkInGroup(dev, theChunk, tags, in->objectId,
+ chunkInInode);
+ }
+ return retVal;
+}
+
+static int yaffs_FindAndDeleteChunkInFile(yaffs_Object * in, int chunkInInode,
+ yaffs_ExtendedTags * tags)
+{
+ /* Get the Tnode, then get the level 0 offset chunk offset */
+ yaffs_Tnode *tn;
+ int theChunk = -1;
+ yaffs_ExtendedTags localTags;
+
+ yaffs_Device *dev = in->myDev;
+ int retVal = -1;
+
+ if (!tags) {
+ /* Passed a NULL, so use our own tags space */
+ tags = &localTags;
+ }
+
+ tn = yaffs_FindLevel0Tnode(dev, &in->variant.fileVariant, chunkInInode);
+
+ if (tn) {
+
+ theChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
+
+ retVal =
+ yaffs_FindChunkInGroup(dev, theChunk, tags, in->objectId,
+ chunkInInode);
+
+ /* Delete the entry in the filestructure (if found) */
+ if (retVal != -1) {
+ yaffs_PutLevel0Tnode(dev,tn,chunkInInode,0);
+ }
+ } else {
+ /*T(("No level 0 found for %d\n", chunkInInode)); */
+ }
+
+ if (retVal == -1) {
+ /* T(("Could not find %d to delete\n",chunkInInode)); */
+ }
+ return retVal;
+}
+
+#ifdef YAFFS_PARANOID
+
+static int yaffs_CheckFileSanity(yaffs_Object * in)
+{
+ int chunk;
+ int nChunks;
+ int fSize;
+ int failed = 0;
+ int objId;
+ yaffs_Tnode *tn;
+ yaffs_Tags localTags;
+ yaffs_Tags *tags = &localTags;
+ int theChunk;
+ int chunkDeleted;
+
+ if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
+ /* T(("Object not a file\n")); */
+ return YAFFS_FAIL;
+ }
+
+ objId = in->objectId;
+ fSize = in->variant.fileVariant.fileSize;
+ nChunks =
+ (fSize + in->myDev->nDataBytesPerChunk - 1) / in->myDev->nDataBytesPerChunk;
+
+ for (chunk = 1; chunk <= nChunks; chunk++) {
+ tn = yaffs_FindLevel0Tnode(in->myDev, &in->variant.fileVariant,
+ chunk);
+
+ if (tn) {
+
+ theChunk = yaffs_GetChunkGroupBase(dev,tn,chunk);
+
+ if (yaffs_CheckChunkBits
+ (dev, theChunk / dev->nChunksPerBlock,
+ theChunk % dev->nChunksPerBlock)) {
+
+ yaffs_ReadChunkTagsFromNAND(in->myDev, theChunk,
+ tags,
+ &chunkDeleted);
+ if (yaffs_TagsMatch
+ (tags, in->objectId, chunk, chunkDeleted)) {
+ /* found it; */
+
+ }
+ } else {
+
+ failed = 1;
+ }
+
+ } else {
+ /* T(("No level 0 found for %d\n", chunk)); */
+ }
+ }
+
+ return failed ? YAFFS_FAIL : YAFFS_OK;
+}
+
+#endif
+
+static int yaffs_PutChunkIntoFile(yaffs_Object * in, int chunkInInode,
+ int chunkInNAND, int inScan)
+{
+ /* NB inScan is zero unless scanning.
+ * For forward scanning, inScan is > 0;
+ * for backward scanning inScan is < 0
+ */
+
+ yaffs_Tnode *tn;
+ yaffs_Device *dev = in->myDev;
+ int existingChunk;
+ yaffs_ExtendedTags existingTags;
+ yaffs_ExtendedTags newTags;
+ unsigned existingSerial, newSerial;
+
+ if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
+ /* Just ignore an attempt at putting a chunk into a non-file during scanning
+ * If it is not during Scanning then something went wrong!
+ */
+ if (!inScan) {
+ T(YAFFS_TRACE_ERROR,
+ (TSTR
+ ("yaffs tragedy:attempt to put data chunk into a non-file"
+ TENDSTR)));
+ YBUG();
+ }
+
+ yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
+ return YAFFS_OK;
+ }
+
+ tn = yaffs_AddOrFindLevel0Tnode(dev,
+ &in->variant.fileVariant,
+ chunkInInode,
+ NULL);
+ if (!tn) {
+ return YAFFS_FAIL;
+ }
+
+ existingChunk = yaffs_GetChunkGroupBase(dev,tn,chunkInInode);
+
+ if (inScan != 0) {
+ /* If we're scanning then we need to test for duplicates
+ * NB This does not need to be efficient since it should only ever
+ * happen when the power fails during a write, then only one
+ * chunk should ever be affected.
+ *
+ * Correction for YAFFS2: This could happen quite a lot and we need to think about efficiency! TODO
+ * Update: For backward scanning we don't need to re-read tags so this is quite cheap.
+ */
+
+ if (existingChunk != 0) {
+ /* NB Right now existing chunk will not be real chunkId if the device >= 32MB
+ * thus we have to do a FindChunkInFile to get the real chunk id.
+ *
+ * We have a duplicate now we need to decide which one to use:
+ *
+ * Backwards scanning YAFFS2: The old one is what we use, dump the new one.
+ * Forward scanning YAFFS2: The new one is what we use, dump the old one.
+ * YAFFS1: Get both sets of tags and compare serial numbers.
+ */
+
+ if (inScan > 0) {
+ /* Only do this for forward scanning */
+ yaffs_ReadChunkWithTagsFromNAND(dev,
+ chunkInNAND,
+ NULL, &newTags);
+
+ /* Do a proper find */
+ existingChunk =
+ yaffs_FindChunkInFile(in, chunkInInode,
+ &existingTags);
+ }
+
+ if (existingChunk <= 0) {
+ /*Hoosterman - how did this happen? */
+
+ T(YAFFS_TRACE_ERROR,
+ (TSTR
+ ("yaffs tragedy: existing chunk < 0 in scan"
+ TENDSTR)));
+
+ }
+
+ /* NB The deleted flags should be false, otherwise the chunks will
+ * not be loaded during a scan
+ */
+
+ newSerial = newTags.serialNumber;
+ existingSerial = existingTags.serialNumber;
+
+ if ((inScan > 0) &&
+ (in->myDev->isYaffs2 ||
+ existingChunk <= 0 ||
+ ((existingSerial + 1) & 3) == newSerial)) {
+ /* Forward scanning.
+ * Use new
+ * Delete the old one and drop through to update the tnode
+ */
+ yaffs_DeleteChunk(dev, existingChunk, 1,
+ __LINE__);
+ } else {
+ /* Backward scanning or we want to use the existing one
+ * Use existing.
+ * Delete the new one and return early so that the tnode isn't changed
+ */
+ yaffs_DeleteChunk(dev, chunkInNAND, 1,
+ __LINE__);
+ return YAFFS_OK;
+ }
+ }
+
+ }
+
+ if (existingChunk == 0) {
+ in->nDataChunks++;
+ }
+
+ yaffs_PutLevel0Tnode(dev,tn,chunkInInode,chunkInNAND);
+
+ return YAFFS_OK;
+}
+
+static int yaffs_ReadChunkDataFromObject(yaffs_Object * in, int chunkInInode,
+ __u8 * buffer)
+{
+ int chunkInNAND = yaffs_FindChunkInFile(in, chunkInInode, NULL);
+
+ if (chunkInNAND >= 0) {
+ return yaffs_ReadChunkWithTagsFromNAND(in->myDev, chunkInNAND,
+ buffer,NULL);
+ } else {
+ T(YAFFS_TRACE_NANDACCESS,
+ (TSTR("Chunk %d not found zero instead" TENDSTR),
+ chunkInNAND));
+ /* get sane (zero) data if you read a hole */
+ memset(buffer, 0, in->myDev->nDataBytesPerChunk);
+ return 0;
+ }
+
+}
+
+void yaffs_DeleteChunk(yaffs_Device * dev, int chunkId, int markNAND, int lyn)