+
+ }
+
+ retVal = newChunkId;
+
+ }
+
+ if (buffer)
+ yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
+
+ return retVal;
+}
+
+/*------------------------ Short Operations Cache ----------------------------------------
+ * In many situations where there is no high level buffering (eg WinCE) a lot of
+ * reads might be short sequential reads, and a lot of writes may be short
+ * sequential writes. eg. scanning/writing a jpeg file.
+ * In these cases, a short read/write cache can provide a huge perfomance benefit
+ * with dumb-as-a-rock code.
+ * In Linux, the page cache provides read buffering aand the short op cache provides write
+ * buffering.
+ *
+ * There are a limited number (~10) of cache chunks per device so that we don't
+ * need a very intelligent search.
+ */
+
+static int yaffs_ObjectHasCachedWriteData(yaffs_Object *obj)
+{
+ yaffs_Device *dev = obj->myDev;
+ int i;
+ yaffs_ChunkCache *cache;
+ int nCaches = obj->myDev->nShortOpCaches;
+
+ for (i = 0; i < nCaches; i++) {
+ cache = &dev->srCache[i];
+ if (cache->object == obj &&
+ cache->dirty)
+ return 1;
+ }
+
+ return 0;
+}
+
+
+static void yaffs_FlushFilesChunkCache(yaffs_Object *obj)
+{
+ yaffs_Device *dev = obj->myDev;
+ int lowest = -99; /* Stop compiler whining. */
+ int i;
+ yaffs_ChunkCache *cache;
+ int chunkWritten = 0;
+ int nCaches = obj->myDev->nShortOpCaches;
+
+ if (nCaches > 0) {
+ do {
+ cache = NULL;
+
+ /* Find the dirty cache for this object with the lowest chunk id. */
+ for (i = 0; i < nCaches; i++) {
+ if (dev->srCache[i].object == obj &&
+ dev->srCache[i].dirty) {
+ if (!cache
+ || dev->srCache[i].chunkId <
+ lowest) {
+ cache = &dev->srCache[i];
+ lowest = cache->chunkId;
+ }
+ }
+ }
+
+ if (cache && !cache->locked) {
+ /* Write it out and free it up */
+
+ chunkWritten =
+ yaffs_WriteChunkDataToObject(cache->object,
+ cache->chunkId,
+ cache->data,
+ cache->nBytes,
+ 1);
+ cache->dirty = 0;
+ cache->object = NULL;
+ }
+
+ } while (cache && chunkWritten > 0);
+
+ if (cache) {
+ /* Hoosterman, disk full while writing cache out. */
+ T(YAFFS_TRACE_ERROR,
+ (TSTR("yaffs tragedy: no space during cache write" TENDSTR)));
+
+ }
+ }
+
+}
+
+/*yaffs_FlushEntireDeviceCache(dev)
+ *
+ *
+ */
+
+void yaffs_FlushEntireDeviceCache(yaffs_Device *dev)
+{
+ yaffs_Object *obj;
+ int nCaches = dev->nShortOpCaches;
+ int i;
+
+ /* Find a dirty object in the cache and flush it...
+ * until there are no further dirty objects.
+ */
+ do {
+ obj = NULL;
+ for (i = 0; i < nCaches && !obj; i++) {
+ if (dev->srCache[i].object &&
+ dev->srCache[i].dirty)
+ obj = dev->srCache[i].object;
+
+ }
+ if (obj)
+ yaffs_FlushFilesChunkCache(obj);
+
+ } while (obj);
+
+}
+
+
+/* Grab us a cache chunk for use.
+ * First look for an empty one.
+ * Then look for the least recently used non-dirty one.
+ * Then look for the least recently used dirty one...., flush and look again.
+ */
+static yaffs_ChunkCache *yaffs_GrabChunkCacheWorker(yaffs_Device *dev)
+{
+ int i;
+
+ if (dev->nShortOpCaches > 0) {
+ for (i = 0; i < dev->nShortOpCaches; i++) {
+ if (!dev->srCache[i].object)
+ return &dev->srCache[i];
+ }
+ }
+
+ return NULL;
+}
+
+static yaffs_ChunkCache *yaffs_GrabChunkCache(yaffs_Device *dev)
+{
+ yaffs_ChunkCache *cache;
+ yaffs_Object *theObj;
+ int usage;
+ int i;
+ int pushout;
+
+ if (dev->nShortOpCaches > 0) {
+ /* Try find a non-dirty one... */
+
+ cache = yaffs_GrabChunkCacheWorker(dev);
+
+ if (!cache) {
+ /* They were all dirty, find the last recently used object and flush
+ * its cache, then find again.
+ * NB what's here is not very accurate, we actually flush the object
+ * the last recently used page.
+ */
+
+ /* With locking we can't assume we can use entry zero */
+
+ theObj = NULL;
+ usage = -1;
+ cache = NULL;
+ pushout = -1;
+
+ for (i = 0; i < dev->nShortOpCaches; i++) {
+ if (dev->srCache[i].object &&
+ !dev->srCache[i].locked &&
+ (dev->srCache[i].lastUse < usage || !cache)) {
+ usage = dev->srCache[i].lastUse;
+ theObj = dev->srCache[i].object;
+ cache = &dev->srCache[i];
+ pushout = i;
+ }
+ }
+
+ if (!cache || cache->dirty) {
+ /* Flush and try again */
+ yaffs_FlushFilesChunkCache(theObj);
+ cache = yaffs_GrabChunkCacheWorker(dev);
+ }
+
+ }
+ return cache;
+ } else
+ return NULL;
+
+}
+
+/* Find a cached chunk */
+static yaffs_ChunkCache *yaffs_FindChunkCache(const yaffs_Object *obj,
+ int chunkId)
+{
+ yaffs_Device *dev = obj->myDev;
+ int i;
+ if (dev->nShortOpCaches > 0) {
+ for (i = 0; i < dev->nShortOpCaches; i++) {
+ if (dev->srCache[i].object == obj &&
+ dev->srCache[i].chunkId == chunkId) {
+ dev->cacheHits++;
+
+ return &dev->srCache[i];
+ }
+ }
+ }
+ return NULL;
+}
+
+/* Mark the chunk for the least recently used algorithym */
+static void yaffs_UseChunkCache(yaffs_Device *dev, yaffs_ChunkCache *cache,
+ int isAWrite)
+{
+
+ if (dev->nShortOpCaches > 0) {
+ if (dev->srLastUse < 0 || dev->srLastUse > 100000000) {
+ /* Reset the cache usages */
+ int i;
+ for (i = 1; i < dev->nShortOpCaches; i++)
+ dev->srCache[i].lastUse = 0;
+
+ dev->srLastUse = 0;
+ }
+
+ dev->srLastUse++;
+
+ cache->lastUse = dev->srLastUse;
+
+ if (isAWrite)
+ cache->dirty = 1;
+ }
+}
+
+/* Invalidate a single cache page.
+ * Do this when a whole page gets written,
+ * ie the short cache for this page is no longer valid.
+ */
+static void yaffs_InvalidateChunkCache(yaffs_Object *object, int chunkId)
+{
+ if (object->myDev->nShortOpCaches > 0) {
+ yaffs_ChunkCache *cache = yaffs_FindChunkCache(object, chunkId);
+
+ if (cache)
+ cache->object = NULL;
+ }
+}
+
+/* Invalidate all the cache pages associated with this object
+ * Do this whenever ther file is deleted or resized.
+ */
+static void yaffs_InvalidateWholeChunkCache(yaffs_Object *in)
+{
+ int i;
+ yaffs_Device *dev = in->myDev;
+
+ if (dev->nShortOpCaches > 0) {
+ /* Invalidate it. */
+ for (i = 0; i < dev->nShortOpCaches; i++) {
+ if (dev->srCache[i].object == in)
+ dev->srCache[i].object = NULL;
+ }
+ }
+}
+
+/*--------------------- Checkpointing --------------------*/
+
+
+static int yaffs_WriteCheckpointValidityMarker(yaffs_Device *dev, int head)
+{
+ yaffs_CheckpointValidity cp;
+
+ memset(&cp, 0, sizeof(cp));
+
+ cp.structType = sizeof(cp);
+ cp.magic = YAFFS_MAGIC;
+ cp.version = YAFFS_CHECKPOINT_VERSION;
+ cp.head = (head) ? 1 : 0;
+
+ return (yaffs_CheckpointWrite(dev, &cp, sizeof(cp)) == sizeof(cp)) ?
+ 1 : 0;
+}
+
+static int yaffs_ReadCheckpointValidityMarker(yaffs_Device *dev, int head)
+{
+ yaffs_CheckpointValidity cp;
+ int ok;
+
+ ok = (yaffs_CheckpointRead(dev, &cp, sizeof(cp)) == sizeof(cp));
+
+ if (ok)
+ ok = (cp.structType == sizeof(cp)) &&
+ (cp.magic == YAFFS_MAGIC) &&
+ (cp.version == YAFFS_CHECKPOINT_VERSION) &&
+ (cp.head == ((head) ? 1 : 0));
+ return ok ? 1 : 0;
+}
+
+static void yaffs_DeviceToCheckpointDevice(yaffs_CheckpointDevice *cp,
+ yaffs_Device *dev)
+{
+ cp->nErasedBlocks = dev->nErasedBlocks;
+ cp->allocationBlock = dev->allocationBlock;
+ cp->allocationPage = dev->allocationPage;
+ cp->nFreeChunks = dev->nFreeChunks;
+
+ cp->nDeletedFiles = dev->nDeletedFiles;
+ cp->nUnlinkedFiles = dev->nUnlinkedFiles;
+ cp->nBackgroundDeletions = dev->nBackgroundDeletions;
+ cp->sequenceNumber = dev->sequenceNumber;
+ cp->oldestDirtySequence = dev->oldestDirtySequence;
+
+}
+
+static void yaffs_CheckpointDeviceToDevice(yaffs_Device *dev,
+ yaffs_CheckpointDevice *cp)
+{
+ dev->nErasedBlocks = cp->nErasedBlocks;
+ dev->allocationBlock = cp->allocationBlock;
+ dev->allocationPage = cp->allocationPage;
+ dev->nFreeChunks = cp->nFreeChunks;
+
+ dev->nDeletedFiles = cp->nDeletedFiles;
+ dev->nUnlinkedFiles = cp->nUnlinkedFiles;
+ dev->nBackgroundDeletions = cp->nBackgroundDeletions;
+ dev->sequenceNumber = cp->sequenceNumber;
+ dev->oldestDirtySequence = cp->oldestDirtySequence;
+}
+
+
+static int yaffs_WriteCheckpointDevice(yaffs_Device *dev)
+{
+ yaffs_CheckpointDevice cp;
+ __u32 nBytes;
+ __u32 nBlocks = (dev->internalEndBlock - dev->internalStartBlock + 1);
+
+ int ok;
+
+ /* Write device runtime values*/
+ yaffs_DeviceToCheckpointDevice(&cp, dev);
+ cp.structType = sizeof(cp);
+
+ ok = (yaffs_CheckpointWrite(dev, &cp, sizeof(cp)) == sizeof(cp));
+
+ /* Write block info */
+ if (ok) {
+ nBytes = nBlocks * sizeof(yaffs_BlockInfo);
+ ok = (yaffs_CheckpointWrite(dev, dev->blockInfo, nBytes) == nBytes);
+ }
+
+ /* Write chunk bits */
+ if (ok) {
+ nBytes = nBlocks * dev->chunkBitmapStride;
+ ok = (yaffs_CheckpointWrite(dev, dev->chunkBits, nBytes) == nBytes);
+ }
+ return ok ? 1 : 0;
+
+}
+
+static int yaffs_ReadCheckpointDevice(yaffs_Device *dev)
+{
+ yaffs_CheckpointDevice cp;
+ __u32 nBytes;
+ __u32 nBlocks = (dev->internalEndBlock - dev->internalStartBlock + 1);
+
+ int ok;
+
+ ok = (yaffs_CheckpointRead(dev, &cp, sizeof(cp)) == sizeof(cp));
+ if (!ok)
+ return 0;
+
+ if (cp.structType != sizeof(cp))
+ return 0;
+
+
+ yaffs_CheckpointDeviceToDevice(dev, &cp);
+
+ nBytes = nBlocks * sizeof(yaffs_BlockInfo);
+
+ ok = (yaffs_CheckpointRead(dev, dev->blockInfo, nBytes) == nBytes);
+
+ if (!ok)
+ return 0;
+ nBytes = nBlocks * dev->chunkBitmapStride;
+
+ ok = (yaffs_CheckpointRead(dev, dev->chunkBits, nBytes) == nBytes);
+
+ return ok ? 1 : 0;
+}
+
+static void yaffs_ObjectToCheckpointObject(yaffs_CheckpointObject *cp,
+ yaffs_Object *obj)
+{
+
+ cp->objectId = obj->objectId;
+ cp->parentId = (obj->parent) ? obj->parent->objectId : 0;
+ cp->hdrChunk = obj->hdrChunk;
+ cp->variantType = obj->variantType;
+ cp->deleted = obj->deleted;
+ cp->softDeleted = obj->softDeleted;
+ cp->unlinked = obj->unlinked;
+ cp->fake = obj->fake;
+ cp->renameAllowed = obj->renameAllowed;
+ cp->unlinkAllowed = obj->unlinkAllowed;
+ cp->serial = obj->serial;
+ cp->nDataChunks = obj->nDataChunks;
+
+ if (obj->variantType == YAFFS_OBJECT_TYPE_FILE)
+ cp->fileSizeOrEquivalentObjectId = obj->variant.fileVariant.fileSize;
+ else if (obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK)
+ cp->fileSizeOrEquivalentObjectId = obj->variant.hardLinkVariant.equivalentObjectId;
+}
+
+static int yaffs_CheckpointObjectToObject(yaffs_Object *obj, yaffs_CheckpointObject *cp)
+{
+
+ yaffs_Object *parent;
+
+ if (obj->variantType != cp->variantType) {
+ T(YAFFS_TRACE_ERROR, (TSTR("Checkpoint read object %d type %d "
+ TCONT("chunk %d does not match existing object type %d")
+ TENDSTR), cp->objectId, cp->variantType, cp->hdrChunk,
+ obj->variantType));
+ return 0;
+ }
+
+ obj->objectId = cp->objectId;
+
+ if (cp->parentId)
+ parent = yaffs_FindOrCreateObjectByNumber(
+ obj->myDev,
+ cp->parentId,
+ YAFFS_OBJECT_TYPE_DIRECTORY);
+ else
+ parent = NULL;
+
+ if (parent) {
+ if (parent->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
+ T(YAFFS_TRACE_ALWAYS, (TSTR("Checkpoint read object %d parent %d type %d"
+ TCONT(" chunk %d Parent type, %d, not directory")
+ TENDSTR),
+ cp->objectId, cp->parentId, cp->variantType,
+ cp->hdrChunk, parent->variantType));
+ return 0;
+ }
+ yaffs_AddObjectToDirectory(parent, obj);
+ }
+
+ obj->hdrChunk = cp->hdrChunk;
+ obj->variantType = cp->variantType;
+ obj->deleted = cp->deleted;
+ obj->softDeleted = cp->softDeleted;
+ obj->unlinked = cp->unlinked;
+ obj->fake = cp->fake;
+ obj->renameAllowed = cp->renameAllowed;
+ obj->unlinkAllowed = cp->unlinkAllowed;
+ obj->serial = cp->serial;
+ obj->nDataChunks = cp->nDataChunks;
+
+ if (obj->variantType == YAFFS_OBJECT_TYPE_FILE)
+ obj->variant.fileVariant.fileSize = cp->fileSizeOrEquivalentObjectId;
+ else if (obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK)
+ obj->variant.hardLinkVariant.equivalentObjectId = cp->fileSizeOrEquivalentObjectId;
+
+ if (obj->hdrChunk > 0)
+ obj->lazyLoaded = 1;
+ return 1;
+}
+
+
+
+static int yaffs_CheckpointTnodeWorker(yaffs_Object *in, yaffs_Tnode *tn,
+ __u32 level, int chunkOffset)
+{
+ int i;
+ yaffs_Device *dev = in->myDev;
+ int ok = 1;
+ int tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
+
+ if (tnodeSize < sizeof(yaffs_Tnode))
+ tnodeSize = sizeof(yaffs_Tnode);
+
+
+ if (tn) {
+ if (level > 0) {
+
+ for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++) {
+ if (tn->internal[i]) {
+ ok = yaffs_CheckpointTnodeWorker(in,
+ tn->internal[i],
+ level - 1,
+ (chunkOffset<<YAFFS_TNODES_INTERNAL_BITS) + i);
+ }
+ }
+ } else if (level == 0) {
+ __u32 baseOffset = chunkOffset << YAFFS_TNODES_LEVEL0_BITS;
+ ok = (yaffs_CheckpointWrite(dev, &baseOffset, sizeof(baseOffset)) == sizeof(baseOffset));
+ if (ok)
+ ok = (yaffs_CheckpointWrite(dev, tn, tnodeSize) == tnodeSize);
+ }
+ }
+
+ return ok;
+
+}
+
+static int yaffs_WriteCheckpointTnodes(yaffs_Object *obj)
+{
+ __u32 endMarker = ~0;
+ int ok = 1;
+
+ if (obj->variantType == YAFFS_OBJECT_TYPE_FILE) {
+ ok = yaffs_CheckpointTnodeWorker(obj,
+ obj->variant.fileVariant.top,
+ obj->variant.fileVariant.topLevel,
+ 0);
+ if (ok)
+ ok = (yaffs_CheckpointWrite(obj->myDev, &endMarker, sizeof(endMarker)) ==
+ sizeof(endMarker));
+ }
+
+ return ok ? 1 : 0;
+}
+
+static int yaffs_ReadCheckpointTnodes(yaffs_Object *obj)
+{
+ __u32 baseChunk;
+ int ok = 1;
+ yaffs_Device *dev = obj->myDev;
+ yaffs_FileStructure *fileStructPtr = &obj->variant.fileVariant;
+ yaffs_Tnode *tn;
+ int nread = 0;
+ int tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
+
+ if (tnodeSize < sizeof(yaffs_Tnode))
+ tnodeSize = sizeof(yaffs_Tnode);
+
+ ok = (yaffs_CheckpointRead(dev, &baseChunk, sizeof(baseChunk)) == sizeof(baseChunk));
+
+ while (ok && (~baseChunk)) {
+ nread++;
+ /* Read level 0 tnode */
+
+
+ tn = yaffs_GetTnodeRaw(dev);
+ if (tn)
+ ok = (yaffs_CheckpointRead(dev, tn, tnodeSize) == tnodeSize);
+ else
+ ok = 0;
+
+ if (tn && ok)
+ ok = yaffs_AddOrFindLevel0Tnode(dev,
+ fileStructPtr,
+ baseChunk,
+ tn) ? 1 : 0;
+
+ if (ok)
+ ok = (yaffs_CheckpointRead(dev, &baseChunk, sizeof(baseChunk)) == sizeof(baseChunk));
+
+ }
+
+ T(YAFFS_TRACE_CHECKPOINT, (
+ TSTR("Checkpoint read tnodes %d records, last %d. ok %d" TENDSTR),
+ nread, baseChunk, ok));
+
+ return ok ? 1 : 0;
+}
+
+
+static int yaffs_WriteCheckpointObjects(yaffs_Device *dev)
+{
+ yaffs_Object *obj;
+ yaffs_CheckpointObject cp;
+ int i;
+ int ok = 1;
+ struct ylist_head *lh;
+
+
+ /* Iterate through the objects in each hash entry,
+ * dumping them to the checkpointing stream.
+ */
+
+ for (i = 0; ok && i < YAFFS_NOBJECT_BUCKETS; i++) {
+ ylist_for_each(lh, &dev->objectBucket[i].list) {
+ if (lh) {
+ obj = ylist_entry(lh, yaffs_Object, hashLink);
+ if (!obj->deferedFree) {
+ yaffs_ObjectToCheckpointObject(&cp, obj);
+ cp.structType = sizeof(cp);
+
+ T(YAFFS_TRACE_CHECKPOINT, (
+ TSTR("Checkpoint write object %d parent %d type %d chunk %d obj addr %x" TENDSTR),
+ cp.objectId, cp.parentId, cp.variantType, cp.hdrChunk, (unsigned) obj));
+
+ ok = (yaffs_CheckpointWrite(dev, &cp, sizeof(cp)) == sizeof(cp));
+
+ if (ok && obj->variantType == YAFFS_OBJECT_TYPE_FILE)
+ ok = yaffs_WriteCheckpointTnodes(obj);
+ }
+ }
+ }
+ }
+
+ /* Dump end of list */
+ memset(&cp, 0xFF, sizeof(yaffs_CheckpointObject));
+ cp.structType = sizeof(cp);
+
+ if (ok)
+ ok = (yaffs_CheckpointWrite(dev, &cp, sizeof(cp)) == sizeof(cp));
+
+ return ok ? 1 : 0;
+}
+
+static int yaffs_ReadCheckpointObjects(yaffs_Device *dev)
+{
+ yaffs_Object *obj;
+ yaffs_CheckpointObject cp;
+ int ok = 1;
+ int done = 0;
+ yaffs_Object *hardList = NULL;
+
+ while (ok && !done) {
+ ok = (yaffs_CheckpointRead(dev, &cp, sizeof(cp)) == sizeof(cp));
+ if (cp.structType != sizeof(cp)) {
+ T(YAFFS_TRACE_CHECKPOINT, (TSTR("struct size %d instead of %d ok %d"TENDSTR),
+ cp.structType, sizeof(cp), ok));
+ ok = 0;
+ }
+
+ T(YAFFS_TRACE_CHECKPOINT, (TSTR("Checkpoint read object %d parent %d type %d chunk %d " TENDSTR),
+ cp.objectId, cp.parentId, cp.variantType, cp.hdrChunk));
+
+ if (ok && cp.objectId == ~0)
+ done = 1;
+ else if (ok) {
+ obj = yaffs_FindOrCreateObjectByNumber(dev, cp.objectId, cp.variantType);
+ if (obj) {
+ ok = yaffs_CheckpointObjectToObject(obj, &cp);
+ if (!ok)
+ break;
+ if (obj->variantType == YAFFS_OBJECT_TYPE_FILE) {
+ ok = yaffs_ReadCheckpointTnodes(obj);
+ } else if (obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
+ obj->hardLinks.next =
+ (struct ylist_head *) hardList;
+ hardList = obj;
+ }
+ } else
+ ok = 0;