+ return newChunkId;
+
+}
+
+/* UpdateObjectHeader updates the header on NAND for an object.
+ * If name is not NULL, then that new name is used.
+ */
+int yaffs_UpdateObjectHeader(yaffs_Object *in, const YCHAR *name, int force,
+ int isShrink, int shadows)
+{
+
+ yaffs_BlockInfo *bi;
+
+ yaffs_Device *dev = in->myDev;
+
+ int prevChunkId;
+ int retVal = 0;
+ int result = 0;
+
+ int newChunkId;
+ yaffs_ExtendedTags newTags;
+ yaffs_ExtendedTags oldTags;
+
+ __u8 *buffer = NULL;
+ YCHAR oldName[YAFFS_MAX_NAME_LENGTH + 1];
+
+ yaffs_ObjectHeader *oh = NULL;
+
+ yaffs_strcpy(oldName, _Y("silly old name"));
+
+
+ if (!in->fake ||
+ in == dev->rootDir || /* The rootDir should also be saved */
+ force) {
+
+ yaffs_CheckGarbageCollection(dev);
+ yaffs_CheckObjectDetailsLoaded(in);
+
+ buffer = yaffs_GetTempBuffer(in->myDev, __LINE__);
+ oh = (yaffs_ObjectHeader *) buffer;
+
+ prevChunkId = in->hdrChunk;
+
+ if (prevChunkId > 0) {
+ result = yaffs_ReadChunkWithTagsFromNAND(dev, prevChunkId,
+ buffer, &oldTags);
+
+ yaffs_VerifyObjectHeader(in, oh, &oldTags, 0);
+
+ memcpy(oldName, oh->name, sizeof(oh->name));
+ }
+
+ memset(buffer, 0xFF, dev->nDataBytesPerChunk);
+
+ oh->type = in->variantType;
+ oh->yst_mode = in->yst_mode;
+ oh->shadowsObject = oh->inbandShadowsObject = shadows;
+
+#ifdef CONFIG_YAFFS_WINCE
+ oh->win_atime[0] = in->win_atime[0];
+ oh->win_ctime[0] = in->win_ctime[0];
+ oh->win_mtime[0] = in->win_mtime[0];
+ oh->win_atime[1] = in->win_atime[1];
+ oh->win_ctime[1] = in->win_ctime[1];
+ oh->win_mtime[1] = in->win_mtime[1];
+#else
+ oh->yst_uid = in->yst_uid;
+ oh->yst_gid = in->yst_gid;
+ oh->yst_atime = in->yst_atime;
+ oh->yst_mtime = in->yst_mtime;
+ oh->yst_ctime = in->yst_ctime;
+ oh->yst_rdev = in->yst_rdev;
+#endif
+ if (in->parent)
+ oh->parentObjectId = in->parent->objectId;
+ else
+ oh->parentObjectId = 0;
+
+ if (name && *name) {
+ memset(oh->name, 0, sizeof(oh->name));
+ yaffs_strncpy(oh->name, name, YAFFS_MAX_NAME_LENGTH);
+ } else if (prevChunkId >= 0)
+ memcpy(oh->name, oldName, sizeof(oh->name));
+ else
+ memset(oh->name, 0, sizeof(oh->name));
+
+ oh->isShrink = isShrink;
+
+ switch (in->variantType) {
+ case YAFFS_OBJECT_TYPE_UNKNOWN:
+ /* Should not happen */
+ break;
+ case YAFFS_OBJECT_TYPE_FILE:
+ oh->fileSize =
+ (oh->parentObjectId == YAFFS_OBJECTID_DELETED
+ || oh->parentObjectId ==
+ YAFFS_OBJECTID_UNLINKED) ? 0 : in->variant.
+ fileVariant.fileSize;
+ break;
+ case YAFFS_OBJECT_TYPE_HARDLINK:
+ oh->equivalentObjectId =
+ in->variant.hardLinkVariant.equivalentObjectId;
+ break;
+ case YAFFS_OBJECT_TYPE_SPECIAL:
+ /* Do nothing */
+ break;
+ case YAFFS_OBJECT_TYPE_DIRECTORY:
+ /* Do nothing */
+ break;
+ case YAFFS_OBJECT_TYPE_SYMLINK:
+ yaffs_strncpy(oh->alias,
+ in->variant.symLinkVariant.alias,
+ YAFFS_MAX_ALIAS_LENGTH);
+ oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
+ break;
+ }
+
+ /* Tags */
+ yaffs_InitialiseTags(&newTags);
+ in->serial++;
+ newTags.chunkId = 0;
+ newTags.objectId = in->objectId;
+ newTags.serialNumber = in->serial;
+
+ /* Add extra info for file header */
+
+ newTags.extraHeaderInfoAvailable = 1;
+ newTags.extraParentObjectId = oh->parentObjectId;
+ newTags.extraFileLength = oh->fileSize;
+ newTags.extraIsShrinkHeader = oh->isShrink;
+ newTags.extraEquivalentObjectId = oh->equivalentObjectId;
+ newTags.extraShadows = (oh->shadowsObject > 0) ? 1 : 0;
+ newTags.extraObjectType = in->variantType;
+
+ yaffs_VerifyObjectHeader(in, oh, &newTags, 1);
+
+ /* Create new chunk in NAND */
+ newChunkId =
+ yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &newTags,
+ (prevChunkId >= 0) ? 1 : 0);
+
+ if (newChunkId >= 0) {
+
+ in->hdrChunk = newChunkId;
+
+ if (prevChunkId >= 0) {
+ yaffs_DeleteChunk(dev, prevChunkId, 1,
+ __LINE__);
+ }
+
+ if (!yaffs_ObjectHasCachedWriteData(in))
+ in->dirty = 0;
+
+ /* If this was a shrink, then mark the block that the chunk lives on */
+ if (isShrink) {
+ bi = yaffs_GetBlockInfo(in->myDev,
+ newChunkId / in->myDev->nChunksPerBlock);
+ bi->hasShrinkHeader = 1;
+ }
+
+ }
+
+ 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));