Adding fsx test to yaffs direct
[yaffs2.git] / yaffs_guts.c
index e8873e1debfd176641816a23490676e9eafddbec..c29c1f990cf0a0e5cfa1e322a2366630d52f0ac3 100644 (file)
@@ -1,7 +1,7 @@
 /*
- * YAFFS: Yet another FFS. A NAND-flash specific file system. 
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
  *
- * Copyright (C) 2002 Aleph One Ltd.
+ * Copyright (C) 2002-2007 Aleph One Ltd.
  *   for Toby Churchill Ltd and Brightstar Engineering
  *
  * Created by Charles Manning <charles@aleph1.co.uk>
@@ -9,11 +9,10 @@
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
- *
  */
 
 const char *yaffs_guts_c_version =
-    "$Id: yaffs_guts.c,v 1.31 2006-03-08 07:59:20 charles Exp $";
+    "$Id: yaffs_guts.c,v 1.52 2007-10-16 00:45:05 charles Exp $";
 
 #include "yportenv.h"
 
@@ -22,6 +21,16 @@ const char *yaffs_guts_c_version =
 #include "yaffs_tagsvalidity.h"
 
 #include "yaffs_tagscompat.h"
+#ifndef  CONFIG_YAFFS_USE_OWN_SORT
+#include "yaffs_qsort.h"
+#endif
+#include "yaffs_nand.h"
+
+#include "yaffs_checkptrw.h"
+
+#include "yaffs_nand.h"
+#include "yaffs_packedtags2.h"
+
 
 #ifdef CONFIG_YAFFS_WINCE
 void yfsd_LockYAFFS(BOOL fsLockOnly);
@@ -32,24 +41,10 @@ void yfsd_UnlockYAFFS(BOOL fsLockOnly);
 
 #include "yaffs_ecc.h"
 
-/* NAND access */
-
-static Y_INLINE int yaffs_ReadChunkWithTagsFromNAND(yaffs_Device * dev,
-                                                   int chunkInNAND,
-                                                   __u8 * buffer,
-                                                   yaffs_ExtendedTags * tags);
-static Y_INLINE int yaffs_WriteChunkWithTagsToNAND(yaffs_Device * dev,
-                                                  int chunkInNAND,
-                                                  const __u8 * data,
-                                                  yaffs_ExtendedTags * tags);
-static Y_INLINE int yaffs_MarkBlockBad(yaffs_Device * dev, int blockNo);
-static Y_INLINE int yaffs_QueryInitialBlockState(yaffs_Device * dev,
-                                                int blockNo,
-                                                yaffs_BlockState * state,
-                                                unsigned *sequenceNumber);
+
 /* Robustification (if it ever comes about...) */
 static void yaffs_RetireBlock(yaffs_Device * dev, int blockInNAND);
-static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND);
+static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND, int erasedOk);
 static void yaffs_HandleWriteChunkOk(yaffs_Device * dev, int chunkInNAND,
                                     const __u8 * data,
                                     const yaffs_ExtendedTags * tags);
@@ -58,6 +53,9 @@ static void yaffs_HandleUpdateChunk(yaffs_Device * dev, int chunkInNAND,
 
 /* Other local prototypes */
 static int yaffs_UnlinkObject( yaffs_Object *obj);
+static int yaffs_ObjectHasCachedWriteData(yaffs_Object *obj);
+
+static void yaffs_HardlinkFixup(yaffs_Device *dev, yaffs_Object *hardList);
 
 static int yaffs_WriteNewChunkWithTagsToNAND(yaffs_Device * dev,
                                             const __u8 * buffer,
@@ -95,10 +93,12 @@ static int yaffs_TagsMatch(const yaffs_ExtendedTags * tags, int objectId,
 
 loff_t yaffs_GetFileSize(yaffs_Object * obj);
 
-static int yaffs_AllocateChunk(yaffs_Device * dev, int useReserve);
+static int yaffs_AllocateChunk(yaffs_Device * dev, int useReserve, yaffs_BlockInfo **blockUsedPtr);
 
 static void yaffs_VerifyFreeChunks(yaffs_Device * dev);
 
+static void yaffs_CheckObjectDetailsLoaded(yaffs_Object *in);
+
 #ifdef YAFFS_PARANOID
 static int yaffs_CheckFileSanity(yaffs_Object * in);
 #else
@@ -108,115 +108,105 @@ static int yaffs_CheckFileSanity(yaffs_Object * in);
 static void yaffs_InvalidateWholeChunkCache(yaffs_Object * in);
 static void yaffs_InvalidateChunkCache(yaffs_Object * object, int chunkId);
 
+static void yaffs_InvalidateCheckpoint(yaffs_Device *dev);
 
-/*
- *   Start of real code.
- */
-
-/*
- * NAND access layer
- */
+static int yaffs_FindChunkInFile(yaffs_Object * in, int chunkInInode,
+                                yaffs_ExtendedTags * tags);
 
+static __u32 yaffs_GetChunkGroupBase(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos);
+static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device * dev,
+                                         yaffs_FileStructure * fStruct,
+                                         __u32 chunkId);
 
-static int yaffs_ReadChunkWithTagsFromNAND(yaffs_Device * dev, int chunkInNAND,
-                                          __u8 * buffer,
-                                          yaffs_ExtendedTags * tags)
-{
-       chunkInNAND -= dev->chunkOffset;
 
-       if (dev->readChunkWithTagsFromNAND)
-               return dev->readChunkWithTagsFromNAND(dev, chunkInNAND, buffer,
-                                                     tags);
-       else
-               return yaffs_TagsCompatabilityReadChunkWithTagsFromNAND(dev,
-                                                                       chunkInNAND,
-                                                                       buffer,
-                                                                       tags);
-}
+/* Function to calculate chunk and offset */
 
-static Y_INLINE int yaffs_WriteChunkWithTagsToNAND(yaffs_Device * dev,
-                                                  int chunkInNAND,
-                                                  const __u8 * buffer,
-                                                  yaffs_ExtendedTags * tags)
+static void yaffs_AddrToChunk(yaffs_Device *dev, loff_t addr, __u32 *chunk, __u32 *offset)
 {
-       chunkInNAND -= dev->chunkOffset;
-
-       if (tags) {
-               tags->sequenceNumber = dev->sequenceNumber;
-               tags->chunkUsed = 1;
-               if (!yaffs_ValidateTags(tags)) {
-                       T(YAFFS_TRACE_ERROR,
-                         (TSTR("Writing uninitialised tags" TENDSTR)));
-                       YBUG();
-               }
-               T(YAFFS_TRACE_WRITE,
-                 (TSTR("Writing chunk %d tags %d %d" TENDSTR), chunkInNAND,
-                  tags->objectId, tags->chunkId));
-       } else {
-               T(YAFFS_TRACE_ERROR, (TSTR("Writing with no tags" TENDSTR)));
-               YBUG();
+       if(dev->chunkShift){
+               /* Easy-peasy power of 2 case */
+               *chunk  = (__u32)(addr >> dev->chunkShift);
+               *offset = (__u32)(addr & dev->chunkMask);
+       }
+       else if(dev->crumbsPerChunk)
+       {
+               /* Case where we're using "crumbs" */
+               *offset = (__u32)(addr & dev->crumbMask);
+               addr >>= dev->crumbShift;
+               *chunk = ((__u32)addr)/dev->crumbsPerChunk;
+               *offset += ((addr - (*chunk * dev->crumbsPerChunk)) << dev->crumbShift);
        }
-
-       if (dev->writeChunkWithTagsToNAND)
-               return dev->writeChunkWithTagsToNAND(dev, chunkInNAND, buffer,
-                                                    tags);
        else
-               return yaffs_TagsCompatabilityWriteChunkWithTagsToNAND(dev,
-                                                                      chunkInNAND,
-                                                                      buffer,
-                                                                      tags);
+               YBUG();
 }
 
-static Y_INLINE int yaffs_MarkBlockBad(yaffs_Device * dev, int blockNo)
-{
-       blockNo -= dev->blockOffset;
-
-       if (dev->markNANDBlockBad)
-               return dev->markNANDBlockBad(dev, blockNo);
-       else
-               return yaffs_TagsCompatabilityMarkNANDBlockBad(dev, blockNo);
-}
-static Y_INLINE int yaffs_QueryInitialBlockState(yaffs_Device * dev,
-                                                int blockNo,
-                                                yaffs_BlockState * state,
-                                                unsigned *sequenceNumber)
+/* Function to return the number of shifts for a power of 2 greater than or equal 
+ * to the given number
+ * Note we don't try to cater for all possible numbers and this does not have to
+ * be hellishly efficient.
+ */
+static __u32 ShiftsGE(__u32 x)
 {
-       blockNo -= dev->blockOffset;
+       int extraBits;
+       int nShifts;
+       
+       nShifts = extraBits = 0;
+       
+       while(x>1){
+               if(x & 1) extraBits++;
+               x>>=1;
+               nShifts++;
+       }
 
-       if (dev->queryNANDBlock)
-               return dev->queryNANDBlock(dev, blockNo, state, sequenceNumber);
-       else
-               return yaffs_TagsCompatabilityQueryNANDBlock(dev, blockNo,
-                                                            state,
-                                                            sequenceNumber);
+       if(extraBits) 
+               nShifts++;
+               
+       return nShifts;
 }
 
-static int yaffs_EraseBlockInNAND(struct yaffs_DeviceStruct *dev,
-                                 int blockInNAND)
+/* Function to return the number of shifts to get a 1 in bit 0
+ */
+static __u32 ShiftDiv(__u32 x)
 {
-       int result;
-
-       blockInNAND -= dev->blockOffset;
-
-       dev->nBlockErasures++;
-       result = dev->eraseBlockInNAND(dev, blockInNAND);
-
-       /* If at first we don't succeed, try again *once*.*/
-       if (!result)
-               result = dev->eraseBlockInNAND(dev, blockInNAND);       
-       return result;
+       int nShifts;
+       
+       nShifts =  0;
+       
+       if(!x) return 0;
+       
+       while( !(x&1)){
+               x>>=1;
+               nShifts++;
+       }
+               
+       return nShifts;
 }
 
-static int yaffs_InitialiseNAND(struct yaffs_DeviceStruct *dev)
-{
-       return dev->initialiseNAND(dev);
-}
+
 
 /* 
  * Temporary buffer manipulations.
  */
 
+static int yaffs_InitialiseTempBuffers(yaffs_Device *dev)      
+{
+       int i;
+       __u8 *buf = (__u8 *)1;
+               
+       memset(dev->tempBuffer,0,sizeof(dev->tempBuffer));
+               
+       for (i = 0; buf && i < YAFFS_N_TEMP_BUFFERS; i++) {
+               dev->tempBuffer[i].line = 0;    /* not in use */
+               dev->tempBuffer[i].buffer = buf =
+                   YMALLOC_DMA(dev->nDataBytesPerChunk);
+       }
+               
+       return buf ? YAFFS_OK : YAFFS_FAIL;
+       
+}
+
 static __u8 *yaffs_GetTempBuffer(yaffs_Device * dev, int lineNo)
 {
        int i, j;
@@ -248,7 +238,7 @@ static __u8 *yaffs_GetTempBuffer(yaffs_Device * dev, int lineNo)
         */
 
        dev->unmanagedTempAllocations++;
-       return YMALLOC(dev->nBytesPerChunk);
+       return YMALLOC(dev->nDataBytesPerChunk);
 
 }
 
@@ -274,6 +264,34 @@ static void yaffs_ReleaseTempBuffer(yaffs_Device * dev, __u8 * buffer,
 
 }
 
+/*
+ * Determine if we have a managed buffer.
+ */
+int yaffs_IsManagedTempBuffer(yaffs_Device * dev, const __u8 * buffer)
+{
+       int i;
+       for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
+               if (dev->tempBuffer[i].buffer == buffer)
+                       return 1;
+
+       }
+
+    for (i = 0; i < dev->nShortOpCaches; i++) {
+        if( dev->srCache[i].data == buffer )
+            return 1;
+
+    }
+
+    if (buffer == dev->checkpointBuffer)
+      return 1;
+
+    T(YAFFS_TRACE_ALWAYS,
+         (TSTR("yaffs: unmaged buffer detected.\n" TENDSTR)));
+    return 0;
+}
+
+
+
 /*
  * Chunk bitmap manipulations
  */
@@ -290,6 +308,16 @@ static Y_INLINE __u8 *yaffs_BlockBits(yaffs_Device * dev, int blk)
            (dev->chunkBitmapStride * (blk - dev->internalStartBlock));
 }
 
+static Y_INLINE void yaffs_VerifyChunkBitId(yaffs_Device *dev, int blk, int chunk)
+{
+       if(blk < dev->internalStartBlock || blk > dev->internalEndBlock ||
+          chunk < 0 || chunk >= dev->nChunksPerBlock) {
+          T(YAFFS_TRACE_ERROR,
+           (TSTR("**>> yaffs: Chunk Id (%d:%d) invalid"TENDSTR),blk,chunk));
+           YBUG();
+       }
+}
+
 static Y_INLINE void yaffs_ClearChunkBits(yaffs_Device * dev, int blk)
 {
        __u8 *blkBits = yaffs_BlockBits(dev, blk);
@@ -301,12 +329,16 @@ static Y_INLINE void yaffs_ClearChunkBit(yaffs_Device * dev, int blk, int chunk)
 {
        __u8 *blkBits = yaffs_BlockBits(dev, blk);
 
+       yaffs_VerifyChunkBitId(dev,blk,chunk);
+
        blkBits[chunk / 8] &= ~(1 << (chunk & 7));
 }
 
 static Y_INLINE void yaffs_SetChunkBit(yaffs_Device * dev, int blk, int chunk)
 {
        __u8 *blkBits = yaffs_BlockBits(dev, blk);
+       
+       yaffs_VerifyChunkBitId(dev,blk,chunk);
 
        blkBits[chunk / 8] |= (1 << (chunk & 7));
 }
@@ -314,6 +346,8 @@ static Y_INLINE void yaffs_SetChunkBit(yaffs_Device * dev, int blk, int chunk)
 static Y_INLINE int yaffs_CheckChunkBit(yaffs_Device * dev, int blk, int chunk)
 {
        __u8 *blkBits = yaffs_BlockBits(dev, blk);
+       yaffs_VerifyChunkBitId(dev,blk,chunk);
+
        return (blkBits[chunk / 8] & (1 << (chunk & 7))) ? 1 : 0;
 }
 
@@ -329,6 +363,491 @@ static Y_INLINE int yaffs_StillSomeChunkBits(yaffs_Device * dev, int blk)
        return 0;
 }
 
+static int yaffs_CountChunkBits(yaffs_Device * dev, int blk)
+{
+       __u8 *blkBits = yaffs_BlockBits(dev, blk);
+       int i;
+       int n = 0;
+       for (i = 0; i < dev->chunkBitmapStride; i++) {
+               __u8 x = *blkBits;
+               while(x){
+                       if(x & 1)
+                               n++;
+                       x >>=1;
+               }
+                       
+               blkBits++;
+       }
+       return n;
+}
+
+/* 
+ * Verification code
+ */
+static int yaffs_SkipVerification(yaffs_Device *dev)
+{
+       return !(yaffs_traceMask & (YAFFS_TRACE_VERIFY | YAFFS_TRACE_VERIFY_FULL));
+}
+
+static int yaffs_SkipFullVerification(yaffs_Device *dev)
+{
+       return !(yaffs_traceMask & (YAFFS_TRACE_VERIFY_FULL));
+}
+
+static int yaffs_SkipNANDVerification(yaffs_Device *dev)
+{
+       return !(yaffs_traceMask & (YAFFS_TRACE_VERIFY_NAND));
+}
+
+static const char * blockStateName[] = {
+"Unknown",
+"Needs scanning",
+"Scanning",
+"Empty",
+"Allocating",
+"Full",
+"Dirty",
+"Checkpoint",
+"Collecting",
+"Dead"
+};
+
+static void yaffs_VerifyBlock(yaffs_Device *dev,yaffs_BlockInfo *bi,int n)
+{
+       int actuallyUsed;
+       int inUse;
+       
+       if(yaffs_SkipVerification(dev))
+               return;
+               
+       /* Report illegal runtime states */
+       if(bi->blockState <0 || bi->blockState >= YAFFS_NUMBER_OF_BLOCK_STATES)
+               T(YAFFS_TRACE_VERIFY,(TSTR("Block %d has undefined state %d"TENDSTR),n,bi->blockState));
+               
+       switch(bi->blockState){
+        case YAFFS_BLOCK_STATE_UNKNOWN:
+        case YAFFS_BLOCK_STATE_SCANNING:
+        case YAFFS_BLOCK_STATE_NEEDS_SCANNING:
+               T(YAFFS_TRACE_VERIFY,(TSTR("Block %d has bad run-state %s"TENDSTR),
+               n,blockStateName[bi->blockState]));
+       }
+       
+       /* Check pages in use and soft deletions are legal */
+       
+       actuallyUsed = bi->pagesInUse - bi->softDeletions;
+       
+       if(bi->pagesInUse < 0 || bi->pagesInUse > dev->nChunksPerBlock ||
+          bi->softDeletions < 0 || bi->softDeletions > dev->nChunksPerBlock ||
+          actuallyUsed < 0 || actuallyUsed > dev->nChunksPerBlock)
+               T(YAFFS_TRACE_VERIFY,(TSTR("Block %d has illegal values pagesInUsed %d softDeletions %d"TENDSTR),
+               n,bi->pagesInUse,bi->softDeletions));
+       
+               
+       /* Check chunk bitmap legal */
+       inUse = yaffs_CountChunkBits(dev,n);
+       if(inUse != bi->pagesInUse)
+               T(YAFFS_TRACE_VERIFY,(TSTR("Block %d has inconsistent values pagesInUse %d counted chunk bits %d"TENDSTR),
+                       n,bi->pagesInUse,inUse));
+       
+       /* Check that the sequence number is valid.
+        * Ten million is legal, but is very unlikely 
+        */
+       if(dev->isYaffs2 && 
+          (bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING || bi->blockState == YAFFS_BLOCK_STATE_FULL) &&
+          (bi->sequenceNumber < YAFFS_LOWEST_SEQUENCE_NUMBER || bi->sequenceNumber > 10000000 ))
+               T(YAFFS_TRACE_VERIFY,(TSTR("Block %d has suspect sequence number of %d"TENDSTR),
+               n,bi->sequenceNumber));
+               
+}
+
+static void yaffs_VerifyCollectedBlock(yaffs_Device *dev,yaffs_BlockInfo *bi,int n)
+{
+       yaffs_VerifyBlock(dev,bi,n);
+       
+       /* After collection the block should be in the erased state */
+       /* TODO: This will need to change if we do partial gc */
+       
+       if(bi->blockState != YAFFS_BLOCK_STATE_EMPTY){
+               T(YAFFS_TRACE_ERROR,(TSTR("Block %d is in state %d after gc, should be erased"TENDSTR),
+                       n,bi->blockState));
+       }
+}
+
+static void yaffs_VerifyBlocks(yaffs_Device *dev)
+{
+       int i;
+       int nBlocksPerState[YAFFS_NUMBER_OF_BLOCK_STATES];
+       int nIllegalBlockStates = 0;
+       
+
+       if(yaffs_SkipVerification(dev))
+               return;
+
+       memset(nBlocksPerState,0,sizeof(nBlocksPerState));
+
+               
+       for(i = dev->internalStartBlock; i <= dev->internalEndBlock; i++){
+               yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,i);
+               yaffs_VerifyBlock(dev,bi,i);
+
+               if(bi->blockState >=0 && bi->blockState < YAFFS_NUMBER_OF_BLOCK_STATES)
+                       nBlocksPerState[bi->blockState]++;
+               else
+                       nIllegalBlockStates++;
+                                       
+       }
+       
+       T(YAFFS_TRACE_VERIFY,(TSTR(""TENDSTR)));
+       T(YAFFS_TRACE_VERIFY,(TSTR("Block summary"TENDSTR)));
+       
+       T(YAFFS_TRACE_VERIFY,(TSTR("%d blocks have illegal states"TENDSTR),nIllegalBlockStates));
+       if(nBlocksPerState[YAFFS_BLOCK_STATE_ALLOCATING] > 1)
+               T(YAFFS_TRACE_VERIFY,(TSTR("Too many allocating blocks"TENDSTR)));
+
+       for(i = 0; i < YAFFS_NUMBER_OF_BLOCK_STATES; i++)
+               T(YAFFS_TRACE_VERIFY,
+                 (TSTR("%s %d blocks"TENDSTR),
+                 blockStateName[i],nBlocksPerState[i]));
+       
+       if(dev->blocksInCheckpoint != nBlocksPerState[YAFFS_BLOCK_STATE_CHECKPOINT])
+               T(YAFFS_TRACE_VERIFY,
+                (TSTR("Checkpoint block count wrong dev %d count %d"TENDSTR),
+                dev->blocksInCheckpoint, nBlocksPerState[YAFFS_BLOCK_STATE_CHECKPOINT]));
+                
+       if(dev->nErasedBlocks != nBlocksPerState[YAFFS_BLOCK_STATE_EMPTY])
+               T(YAFFS_TRACE_VERIFY,
+                (TSTR("Erased block count wrong dev %d count %d"TENDSTR),
+                dev->nErasedBlocks, nBlocksPerState[YAFFS_BLOCK_STATE_EMPTY]));
+                
+       if(nBlocksPerState[YAFFS_BLOCK_STATE_COLLECTING] > 1)
+               T(YAFFS_TRACE_VERIFY,
+                (TSTR("Too many collecting blocks %d (max is 1)"TENDSTR),
+                nBlocksPerState[YAFFS_BLOCK_STATE_COLLECTING]));
+
+       T(YAFFS_TRACE_VERIFY,(TSTR(""TENDSTR)));
+
+}
+
+/*
+ * Verify the object header. oh must be valid, but obj and tags may be NULL in which
+ * case those tests will not be performed.
+ */
+static void yaffs_VerifyObjectHeader(yaffs_Object *obj, yaffs_ObjectHeader *oh, yaffs_ExtendedTags *tags, int parentCheck)
+{
+       if(yaffs_SkipVerification(obj->myDev))
+               return;
+               
+       if(!(tags && obj && oh)){
+               T(YAFFS_TRACE_VERIFY,
+                               (TSTR("Verifying object header tags %x obj %x oh %x"TENDSTR),
+                               (__u32)tags,(__u32)obj,(__u32)oh));
+               return;
+       }
+       
+       if(oh->type <= YAFFS_OBJECT_TYPE_UNKNOWN ||
+          oh->type > YAFFS_OBJECT_TYPE_MAX)
+               T(YAFFS_TRACE_VERIFY,
+                (TSTR("Obj %d header type is illegal value 0x%x"TENDSTR),
+                tags->objectId, oh->type));
+
+       if(tags->objectId != obj->objectId)
+               T(YAFFS_TRACE_VERIFY,
+                (TSTR("Obj %d header mismatch objectId %d"TENDSTR),
+                tags->objectId, obj->objectId));
+
+
+       /*
+        * Check that the object's parent ids match if parentCheck requested.
+        * 
+        * Tests do not apply to the root object.
+        */
+       
+       if(parentCheck && tags->objectId > 1 && !obj->parent)
+               T(YAFFS_TRACE_VERIFY,
+                (TSTR("Obj %d header mismatch parentId %d obj->parent is NULL"TENDSTR),
+                tags->objectId, oh->parentObjectId));
+               
+       
+       if(parentCheck && obj->parent &&
+          oh->parentObjectId != obj->parent->objectId && 
+          (oh->parentObjectId != YAFFS_OBJECTID_UNLINKED ||
+           obj->parent->objectId != YAFFS_OBJECTID_DELETED))
+               T(YAFFS_TRACE_VERIFY,
+                (TSTR("Obj %d header mismatch parentId %d parentObjectId %d"TENDSTR),
+                tags->objectId, oh->parentObjectId, obj->parent->objectId));
+               
+       
+       if(tags->objectId > 1 && oh->name[0] == 0) /* Null name */
+               T(YAFFS_TRACE_VERIFY,
+               (TSTR("Obj %d header name is NULL"TENDSTR),
+                obj->objectId));
+
+       if(tags->objectId > 1 && ((__u8)(oh->name[0])) == 0xff) /* Trashed name */
+               T(YAFFS_TRACE_VERIFY,
+               (TSTR("Obj %d header name is 0xFF"TENDSTR),
+                obj->objectId));
+}
+
+
+
+static int yaffs_VerifyTnodeWorker(yaffs_Object * obj, yaffs_Tnode * tn,
+                                       __u32 level, int chunkOffset)
+{
+       int i;
+       yaffs_Device *dev = obj->myDev;
+       int ok = 1;
+       int nTnodeBytes = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
+
+       if (tn) {
+               if (level > 0) {
+
+                       for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++){
+                               if (tn->internal[i]) {
+                                       ok = yaffs_VerifyTnodeWorker(obj,
+                                                       tn->internal[i],
+                                                       level - 1,
+                                                       (chunkOffset<<YAFFS_TNODES_INTERNAL_BITS) + i);
+                               }
+                       }
+               } else if (level == 0) {
+                       int i;
+                       yaffs_ExtendedTags tags;
+                       __u32 objectId = obj->objectId;
+                       
+                       chunkOffset <<=  YAFFS_TNODES_LEVEL0_BITS;
+                       
+                       for(i = 0; i < YAFFS_NTNODES_LEVEL0; i++){
+                               __u32 theChunk = yaffs_GetChunkGroupBase(dev,tn,i);
+                               
+                               if(theChunk > 0){
+                                       /* T(~0,(TSTR("verifying (%d:%d) %d"TENDSTR),tags.objectId,tags.chunkId,theChunk)); */
+                                       yaffs_ReadChunkWithTagsFromNAND(dev,theChunk,NULL, &tags);
+                                       if(tags.objectId != objectId || tags.chunkId != chunkOffset){
+                                               T(~0,(TSTR("Object %d chunkId %d NAND mismatch chunk %d tags (%d:%d)"TENDSTR),
+                                                       objectId, chunkOffset, theChunk,
+                                                       tags.objectId, tags.chunkId));
+                                       }
+                               }
+                               chunkOffset++;
+                       }
+               }
+       }
+
+       return ok;
+
+}
+
+
+static void yaffs_VerifyFile(yaffs_Object *obj)
+{
+       int requiredTallness;
+       int actualTallness;
+       __u32 lastChunk;
+       __u32 x;
+       __u32 i;
+       int ok;
+       yaffs_Device *dev;
+       yaffs_ExtendedTags tags;
+       yaffs_Tnode *tn;
+       __u32 objectId;
+       
+       if(obj && yaffs_SkipVerification(obj->myDev))
+               return;
+       
+       dev = obj->myDev;
+       objectId = obj->objectId;
+       
+       /* Check file size is consistent with tnode depth */
+       lastChunk =  obj->variant.fileVariant.fileSize / dev->nDataBytesPerChunk + 1;
+       x = lastChunk >> YAFFS_TNODES_LEVEL0_BITS;
+       requiredTallness = 0;
+       while (x> 0) {
+               x >>= YAFFS_TNODES_INTERNAL_BITS;
+               requiredTallness++;
+       }
+       
+       actualTallness = obj->variant.fileVariant.topLevel;
+       
+       if(requiredTallness > actualTallness )
+               T(YAFFS_TRACE_VERIFY,
+               (TSTR("Obj %d had tnode tallness %d, needs to be %d"TENDSTR),
+                obj->objectId,actualTallness, requiredTallness));
+       
+       
+       /* Check that the chunks in the tnode tree are all correct. 
+        * We do this by scanning through the tnode tree and
+        * checking the tags for every chunk match.
+        */
+
+       if(yaffs_SkipNANDVerification(dev))
+               return;
+               
+       for(i = 1; i <= lastChunk; i++){
+               tn = yaffs_FindLevel0Tnode(dev, &obj->variant.fileVariant,i);
+
+               if (tn) {
+                       __u32 theChunk = yaffs_GetChunkGroupBase(dev,tn,i);
+                       if(theChunk > 0){
+                               /* T(~0,(TSTR("verifying (%d:%d) %d"TENDSTR),objectId,i,theChunk)); */
+                               yaffs_ReadChunkWithTagsFromNAND(dev,theChunk,NULL, &tags);
+                               if(tags.objectId != objectId || tags.chunkId != i){
+                                       T(~0,(TSTR("Object %d chunkId %d NAND mismatch chunk %d tags (%d:%d)"TENDSTR),
+                                               objectId, i, theChunk,
+                                               tags.objectId, tags.chunkId));
+                               }
+                       }
+               }
+
+       }
+
+}
+
+static void yaffs_VerifyDirectory(yaffs_Object *obj)
+{
+       if(obj && yaffs_SkipVerification(obj->myDev))
+               return;
+       
+}
+
+static void yaffs_VerifyHardLink(yaffs_Object *obj)
+{
+       if(obj && yaffs_SkipVerification(obj->myDev))
+               return;
+               
+       /* Verify sane equivalent object */
+}
+
+static void yaffs_VerifySymlink(yaffs_Object *obj)
+{
+       if(obj && yaffs_SkipVerification(obj->myDev))
+               return;
+               
+       /* Verify symlink string */
+}
+
+static void yaffs_VerifySpecial(yaffs_Object *obj)
+{
+       if(obj && yaffs_SkipVerification(obj->myDev))
+               return;
+}
+
+static void yaffs_VerifyObject(yaffs_Object *obj)
+{
+       yaffs_Device *dev;
+       
+       __u32 chunkMin;
+       __u32 chunkMax;
+       
+       __u32 chunkIdOk;
+       __u32 chunkIsLive;
+       
+       if(!obj)
+               return;
+       
+       dev = obj->myDev;
+       
+       if(yaffs_SkipVerification(dev))
+               return;
+               
+       /* Check sane object header chunk */
+       
+       chunkMin = dev->internalStartBlock * dev->nChunksPerBlock;
+       chunkMax = (dev->internalEndBlock+1) * dev->nChunksPerBlock - 1;
+       
+       chunkIdOk = (obj->chunkId >= chunkMin && obj->chunkId <= chunkMax);
+       chunkIsLive = chunkIdOk && 
+                       yaffs_CheckChunkBit(dev, 
+                                           obj->chunkId / dev->nChunksPerBlock,
+                                           obj->chunkId % dev->nChunksPerBlock);
+       if(!obj->fake && 
+           (!chunkIdOk || !chunkIsLive)) {
+          T(YAFFS_TRACE_VERIFY,
+          (TSTR("Obj %d has chunkId %d %s %s"TENDSTR),
+          obj->objectId,obj->chunkId,
+          chunkIdOk ? "" : ",out of range",
+          chunkIsLive || !chunkIdOk ? "" : ",marked as deleted"));
+       }
+       
+       if(chunkIdOk && chunkIsLive &&!yaffs_SkipNANDVerification(dev)) {
+               yaffs_ExtendedTags tags;
+               yaffs_ObjectHeader *oh;
+               __u8 *buffer = yaffs_GetTempBuffer(dev,__LINE__);
+               
+               oh = (yaffs_ObjectHeader *)buffer;
+               
+               yaffs_ReadChunkWithTagsFromNAND(dev, obj->chunkId,buffer, &tags);
+               
+               yaffs_VerifyObjectHeader(obj,oh,&tags,1);
+               
+               yaffs_ReleaseTempBuffer(dev,buffer,__LINE__);
+       }
+       
+       /* Verify it has a parent */
+       if(obj && !obj->fake &&
+          (!obj->parent || obj->parent->myDev != dev)){
+          T(YAFFS_TRACE_VERIFY,
+          (TSTR("Obj %d has parent pointer %p which does not look like an object"TENDSTR),
+          obj->objectId,obj->parent));    
+       }
+       
+       /* Verify parent is a directory */
+       if(obj->parent && obj->parent->variantType != YAFFS_OBJECT_TYPE_DIRECTORY){
+          T(YAFFS_TRACE_VERIFY,
+          (TSTR("Obj %d's parent is not a directory (type %d)"TENDSTR),
+          obj->objectId,obj->parent->variantType));       
+       }
+       
+       switch(obj->variantType){
+       case YAFFS_OBJECT_TYPE_FILE:
+               yaffs_VerifyFile(obj);
+               break;
+       case YAFFS_OBJECT_TYPE_SYMLINK:
+               yaffs_VerifySymlink(obj);
+               break;
+       case YAFFS_OBJECT_TYPE_DIRECTORY:
+               yaffs_VerifyDirectory(obj);
+               break;
+       case YAFFS_OBJECT_TYPE_HARDLINK:
+               yaffs_VerifyHardLink(obj);
+               break;
+       case YAFFS_OBJECT_TYPE_SPECIAL:
+               yaffs_VerifySpecial(obj);
+               break;
+       case YAFFS_OBJECT_TYPE_UNKNOWN:
+       default:
+               T(YAFFS_TRACE_VERIFY,
+               (TSTR("Obj %d has illegaltype %d"TENDSTR),
+               obj->objectId,obj->variantType));          
+               break;
+       }
+       
+       
+}
+
+static void yaffs_VerifyObjects(yaffs_Device *dev)
+{
+       yaffs_Object *obj;
+       int i;
+       struct list_head *lh;
+
+       if(yaffs_SkipVerification(dev))
+               return;
+       
+       /* Iterate through the objects in each hash entry */
+        
+        for(i = 0; i <  YAFFS_NOBJECT_BUCKETS; i++){
+               list_for_each(lh, &dev->objectBucket[i].list) {
+                       if (lh) {
+                               obj = list_entry(lh, yaffs_Object, hashLink);
+                               yaffs_VerifyObject(obj);
+                       }
+               }
+        }
+
+}
+
+
 /*
  *  Simple hash function. Needs to have a reasonable spread
  */
@@ -376,10 +895,15 @@ static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
        int retval = YAFFS_OK;
        __u8 *data = yaffs_GetTempBuffer(dev, __LINE__);
        yaffs_ExtendedTags tags;
+       int result;
 
-       yaffs_ReadChunkWithTagsFromNAND(dev, chunkInNAND, data, &tags);
+       result = yaffs_ReadChunkWithTagsFromNAND(dev, chunkInNAND, data, &tags);
+       
+       if(tags.eccResult > YAFFS_ECC_RESULT_NO_ERROR)
+               retval = YAFFS_FAIL;
+               
 
-       if (!yaffs_CheckFF(data, dev->nBytesPerChunk) || tags.chunkUsed) {
+       if (!yaffs_CheckFF(data, dev->nDataBytesPerChunk) || tags.chunkUsed) {
                T(YAFFS_TRACE_NANDACCESS,
                  (TSTR("Chunk %d not erased" TENDSTR), chunkInNAND));
                retval = YAFFS_FAIL;
@@ -396,51 +920,88 @@ static int yaffs_WriteNewChunkWithTagsToNAND(struct yaffs_DeviceStruct *dev,
                                             yaffs_ExtendedTags * tags,
                                             int useReserve)
 {
+       int attempts = 0;
+       int writeOk = 0;
        int chunk;
 
-       int writeOk = 1;
-       int attempts = 0;
+       yaffs_InvalidateCheckpoint(dev);
 
        do {
-               chunk = yaffs_AllocateChunk(dev, useReserve);
+               yaffs_BlockInfo *bi = 0;
+               int erasedOk = 0;
 
-               if (chunk >= 0) {
+               chunk = yaffs_AllocateChunk(dev, useReserve, &bi);
+               if (chunk < 0) {
+                       /* no space */
+                       break;
+               }
 
-                       /* First check this chunk is erased... */
-#ifndef CONFIG_YAFFS_DISABLE_CHUNK_ERASED_CHECK
-                       writeOk = yaffs_CheckChunkErased(dev, chunk);
+               /* First check this chunk is erased, if it needs
+                * checking.  The checking policy (unless forced
+                * always on) is as follows:
+                *
+                * Check the first page we try to write in a block.
+                * If the check passes then we don't need to check any
+                * more.        If the check fails, we check again...
+                * If the block has been erased, we don't need to check.
+                *
+                * However, if the block has been prioritised for gc,
+                * then we think there might be something odd about
+                * this block and stop using it.
+                *
+                * Rationale: We should only ever see chunks that have
+                * not been erased if there was a partially written
+                * chunk due to power loss.  This checking policy should
+                * catch that case with very few checks and thus save a
+                * lot of checks that are most likely not needed.
+                */
+               if (bi->gcPrioritise) {
+                       yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
+                       /* try another chunk */
+                       continue;
+               }
+
+               /* let's give it a try */
+               attempts++;
+
+#ifdef CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED
+               bi->skipErasedCheck = 0;
 #endif
-                       if (!writeOk) {
+               if (!bi->skipErasedCheck) {
+                       erasedOk = yaffs_CheckChunkErased(dev, chunk);
+                       if (erasedOk != YAFFS_OK) {
                                T(YAFFS_TRACE_ERROR,
-                                 (TSTR
-                                  ("**>> yaffs chunk %d was not erased"
-                                   TENDSTR), chunk));
-                       } else {
-                               writeOk =
-                                   yaffs_WriteChunkWithTagsToNAND(dev, chunk,
-                                                                  data, tags);
-                       }
-                       attempts++;
+                               (TSTR ("**>> yaffs chunk %d was not erased"
+                               TENDSTR), chunk));
 
-                       if (writeOk) {
-                               /*
-                                *  Copy the data into the robustification buffer.
-                                *  NB We do this at the end to prevent duplicates in the case of a write error.
-                                *  Todo
-                                */
-                               yaffs_HandleWriteChunkOk(dev, chunk, data,
-                                                        tags);
-                       } else {
-                               yaffs_HandleWriteChunkError(dev, chunk);
+                               /* try another chunk */
+                               continue;
                        }
+                       bi->skipErasedCheck = 1;
                }
 
-       } while (chunk >= 0 && !writeOk);
+               writeOk = yaffs_WriteChunkWithTagsToNAND(dev, chunk,
+                               data, tags);
+               if (writeOk != YAFFS_OK) {
+                       yaffs_HandleWriteChunkError(dev, chunk, erasedOk);
+                       /* try another chunk */
+                       continue;
+               }
+
+               /* Copy the data into the robustification buffer */
+               yaffs_HandleWriteChunkOk(dev, chunk, data, tags);
+
+       } while (writeOk != YAFFS_OK && 
+               (yaffs_wr_attempts <= 0 || attempts <= yaffs_wr_attempts));
+       
+       if(!writeOk)
+               chunk = -1;
 
        if (attempts > 1) {
                T(YAFFS_TRACE_ERROR,
-                 (TSTR("**>> yaffs write required %d attempts" TENDSTR),
-                  attempts));
+                       (TSTR("**>> yaffs write required %d attempts" TENDSTR),
+                       attempts));
+
                dev->nRetriedWrites += (attempts - 1);
        }
 
@@ -453,11 +1014,15 @@ static int yaffs_WriteNewChunkWithTagsToNAND(struct yaffs_DeviceStruct *dev,
  
 static void yaffs_RetireBlock(yaffs_Device * dev, int blockInNAND)
 {
+       yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockInNAND);
 
+       yaffs_InvalidateCheckpoint(dev);
+       
        yaffs_MarkBlockBad(dev, blockInNAND);
 
-       yaffs_GetBlockInfo(dev, blockInNAND)->blockState =
-           YAFFS_BLOCK_STATE_DEAD;
+       bi->blockState = YAFFS_BLOCK_STATE_DEAD;
+       bi->gcPrioritise = 0;
+       bi->needsRetiring = 0;
 
        dev->nRetiredBlocks++;
 }
@@ -478,12 +1043,40 @@ static void yaffs_HandleUpdateChunk(yaffs_Device * dev, int chunkInNAND,
 {
 }
 
-static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND)
+void yaffs_HandleChunkError(yaffs_Device *dev, yaffs_BlockInfo *bi)
 {
+       if(!bi->gcPrioritise){
+               bi->gcPrioritise = 1;
+               dev->hasPendingPrioritisedGCs = 1;
+               bi->chunkErrorStrikes ++;
+               
+               if(bi->chunkErrorStrikes > 3){
+                       bi->needsRetiring = 1; /* Too many stikes, so retire this */
+                       T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Block struck out" TENDSTR)));
+
+               }
+               
+       }
+}
+
+static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND, int erasedOk)
+{
+
        int blockInNAND = chunkInNAND / dev->nChunksPerBlock;
+       yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockInNAND);
 
-       /* Mark the block for retirement */
-       yaffs_GetBlockInfo(dev, blockInNAND)->needsRetiring = 1;
+       yaffs_HandleChunkError(dev,bi);
+               
+       
+       if(erasedOk ) {
+               /* Was an actual write failure, so mark the block for retirement  */
+               bi->needsRetiring = 1;
+               T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
+                 (TSTR("**>> Block %d needs retiring" TENDSTR), blockInNAND));
+
+               
+       }
+       
        /* Delete the chunk */
        yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
 }
@@ -498,7 +1091,7 @@ static __u16 yaffs_CalcNameSum(const YCHAR * name)
 
        YUCHAR *bname = (YUCHAR *) name;
        if (bname) {
-               while ((*bname) && (i <= YAFFS_MAX_NAME_LENGTH)) {
+               while ((*bname) && (i < (YAFFS_MAX_NAME_LENGTH/2))) {
 
 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
                        sum += yaffs_toupper(*bname) * i;
@@ -606,6 +1199,7 @@ static int yaffs_CreateTnodes(yaffs_Device * dev, int nTnodes)
                T(YAFFS_TRACE_ERROR,
                  (TSTR
                   ("yaffs: Could not add tnodes to management list" TENDSTR)));
+                  return YAFFS_FAIL;
 
        } else {
                tnl->tnodes = newTnodes;
@@ -620,7 +1214,7 @@ static int yaffs_CreateTnodes(yaffs_Device * dev, int nTnodes)
 
 /* GetTnode gets us a clean tnode. Tries to make allocate more if we run out */
 
-static yaffs_Tnode *yaffs_GetTnode(yaffs_Device * dev)
+static yaffs_Tnode *yaffs_GetTnodeRaw(yaffs_Device * dev)
 {
        yaffs_Tnode *tn = NULL;
 
@@ -640,13 +1234,21 @@ static yaffs_Tnode *yaffs_GetTnode(yaffs_Device * dev)
 #endif
                dev->freeTnodes = dev->freeTnodes->internal[0];
                dev->nFreeTnodes--;
-               /* zero out */
-               memset(tn, 0, (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
        }
 
        return tn;
 }
 
+static yaffs_Tnode *yaffs_GetTnode(yaffs_Device * dev)
+{
+       yaffs_Tnode *tn = yaffs_GetTnodeRaw(dev);
+       
+       if(tn)
+               memset(tn, 0, (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
+
+       return tn;      
+}
+
 /* FreeTnode frees up a tnode and puts it back on the free list */
 static void yaffs_FreeTnode(yaffs_Device * dev, yaffs_Tnode * tn)
 {
@@ -722,7 +1324,7 @@ void yaffs_PutLevel0Tnode(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos, unsi
   }
 }
 
-__u32 yaffs_GetChunkGroupBase(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos)
+static __u32 yaffs_GetChunkGroupBase(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos)
 {
   __u32 *map = (__u32 *)tn;
   __u32 bitInMap;
@@ -813,18 +1415,21 @@ static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device * dev,
  *  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
  *
  * Used when modifying the tree.
+ *
+ *  If the tn argument is NULL, then a fresh tnode will be added otherwise the specified tn will
+ *  be plugged into the ttree.
  */
  
 static yaffs_Tnode *yaffs_AddOrFindLevel0Tnode(yaffs_Device * dev,
                                               yaffs_FileStructure * fStruct,
-                                              __u32 chunkId)
+                                              __u32 chunkId,
+                                              yaffs_Tnode *passedTn)
 {
 
-       yaffs_Tnode *tn;
-
        int requiredTallness;
        int i;
        int l;
+       yaffs_Tnode *tn;
 
        __u32 x;
 
@@ -870,19 +1475,42 @@ static yaffs_Tnode *yaffs_AddOrFindLevel0Tnode(yaffs_Device * dev,
 
        l = fStruct->topLevel;
        tn = fStruct->top;
-       while (l > 0 && tn) {
-               x = (chunkId >>
-                    ( YAFFS_TNODES_LEVEL0_BITS +
-                     (l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
-                   YAFFS_TNODES_INTERNAL_MASK;
-
-
-               if (!tn->internal[x])
-                       tn->internal[x] = yaffs_GetTnode(dev);
-
-               tn = tn->internal[x];
-               l--;
-
+       
+       if(l > 0) {
+               while (l > 0 && tn) {
+                       x = (chunkId >>
+                            ( YAFFS_TNODES_LEVEL0_BITS +
+                             (l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
+                           YAFFS_TNODES_INTERNAL_MASK;
+
+
+                       if((l>1) && !tn->internal[x]){
+                               /* Add missing non-level-zero tnode */
+                               tn->internal[x] = yaffs_GetTnode(dev);
+
+                       } else if(l == 1) {
+                               /* Looking from level 1 at level 0 */
+                               if (passedTn) {
+                                       /* If we already have one, then release it.*/
+                                       if(tn->internal[x])
+                                               yaffs_FreeTnode(dev,tn->internal[x]);
+                                       tn->internal[x] = passedTn;
+                       
+                               } else if(!tn->internal[x]) {
+                                       /* Don't have one, none passed in */
+                                       tn->internal[x] = yaffs_GetTnode(dev);
+                               }
+                       }
+               
+                       tn = tn->internal[x];
+                       l--;
+               }
+       } else {
+               /* top is level 0 */
+               if(passedTn) {
+                       memcpy(tn,passedTn,(dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
+                       yaffs_FreeTnode(dev,passedTn);
+               }
        }
 
        return tn;
@@ -1214,8 +1842,13 @@ static int yaffs_CreateFreeObjects(yaffs_Device * dev, int nObjects)
 
        /* make these things */
        newObjects = YMALLOC(nObjects * sizeof(yaffs_Object));
+       list = YMALLOC(sizeof(yaffs_ObjectList));
 
-       if (!newObjects) {
+       if (!newObjects || !list) {
+               if(newObjects)
+                       YFREE(newObjects);
+               if(list)
+                       YFREE(list);
                T(YAFFS_TRACE_ALLOCATE,
                  (TSTR("yaffs: Could not allocate more objects" TENDSTR)));
                return YAFFS_FAIL;
@@ -1234,15 +1867,9 @@ static int yaffs_CreateFreeObjects(yaffs_Device * dev, int nObjects)
 
        /* Now add this bunch of Objects to a list for freeing up. */
 
-       list = YMALLOC(sizeof(yaffs_ObjectList));
-       if (!list) {
-               T(YAFFS_TRACE_ALLOCATE,
-                 (TSTR("Could not add objects to management list" TENDSTR)));
-       } else {
-               list->objects = newObjects;
-               list->next = dev->allocatedObjectList;
-               dev->allocatedObjectList = list;
-       }
+       list->objects = newObjects;
+       list->next = dev->allocatedObjectList;
+       dev->allocatedObjectList = list;
 
        return YAFFS_OK;
 }
@@ -1499,12 +2126,25 @@ yaffs_Object *yaffs_CreateNewObject(yaffs_Device * dev, int number,
 {
 
        yaffs_Object *theObject;
+       yaffs_Tnode *tn;
 
        if (number < 0) {
                number = yaffs_CreateNewObjectNumber(dev);
        }
 
        theObject = yaffs_AllocateEmptyObject(dev);
+       if(!theObject)
+               return NULL;
+               
+       if(type == YAFFS_OBJECT_TYPE_FILE){
+               tn = yaffs_GetTnode(dev);
+               if(!tn){
+                       yaffs_FreeObject(theObject);
+                       return NULL;
+               }
+       }
+               
+       
 
        if (theObject) {
                theObject->fake = 0;
@@ -1531,8 +2171,7 @@ yaffs_Object *yaffs_CreateNewObject(yaffs_Device * dev, int number,
                        theObject->variant.fileVariant.scannedFileSize = 0;
                        theObject->variant.fileVariant.shrinkSize = 0xFFFFFFFF; /* max __u32 */
                        theObject->variant.fileVariant.topLevel = 0;
-                       theObject->variant.fileVariant.top =
-                           yaffs_GetTnode(dev);
+                       theObject->variant.fileVariant.top = tn;
                        break;
                case YAFFS_OBJECT_TYPE_DIRECTORY:
                        INIT_LIST_HEAD(&theObject->variant.directoryVariant.
@@ -1569,6 +2208,7 @@ static yaffs_Object *yaffs_FindOrCreateObjectByNumber(yaffs_Device * dev,
        return theObject;
 
 }
+                       
 
 static YCHAR *yaffs_CloneString(const YCHAR * str)
 {
@@ -1576,7 +2216,8 @@ static YCHAR *yaffs_CloneString(const YCHAR * str)
 
        if (str && *str) {
                newStr = YMALLOC((yaffs_strlen(str) + 1) * sizeof(YCHAR));
-               yaffs_strcpy(newStr, str);
+               if(newStr)
+                       yaffs_strcpy(newStr, str);
        }
 
        return newStr;
@@ -1600,6 +2241,7 @@ static yaffs_Object *yaffs_MknodObject(yaffs_ObjectType type,
                                       const YCHAR * aliasString, __u32 rdev)
 {
        yaffs_Object *in;
+       YCHAR *str;
 
        yaffs_Device *dev = parent->myDev;
 
@@ -1609,6 +2251,16 @@ static yaffs_Object *yaffs_MknodObject(yaffs_ObjectType type,
        }
 
        in = yaffs_CreateNewObject(dev, -1, type);
+       
+       if(type == YAFFS_OBJECT_TYPE_SYMLINK){
+               str = yaffs_CloneString(aliasString);
+               if(!str){
+                       yaffs_FreeObject(in);
+                       return NULL;
+               }
+       }
+       
+       
 
        if (in) {
                in->chunkId = -1;
@@ -1640,8 +2292,7 @@ static yaffs_Object *yaffs_MknodObject(yaffs_ObjectType type,
 
                switch (type) {
                case YAFFS_OBJECT_TYPE_SYMLINK:
-                       in->variant.symLinkVariant.alias =
-                           yaffs_CloneString(aliasString);
+                       in->variant.symLinkVariant.alias = str;
                        break;
                case YAFFS_OBJECT_TYPE_HARDLINK:
                        in->variant.hardLinkVariant.equivalentObject =
@@ -1792,6 +2443,15 @@ int yaffs_RenameObject(yaffs_Object * oldDir, const YCHAR * oldName,
 #endif
 
        obj = yaffs_FindObjectByName(oldDir, oldName);
+       /* Check new name to long. */
+       if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK &&
+           yaffs_strlen(newName) > YAFFS_MAX_ALIAS_LENGTH)
+         /* ENAMETOOLONG */
+         return YAFFS_FAIL;
+       else if (obj->variantType != YAFFS_OBJECT_TYPE_SYMLINK &&
+                yaffs_strlen(newName) > YAFFS_MAX_NAME_LENGTH)
+         /* ENAMETOOLONG */
+         return YAFFS_FAIL;
 
        if (obj && obj->renameAllowed) {
 
@@ -1819,11 +2479,16 @@ int yaffs_RenameObject(yaffs_Object * oldDir, const YCHAR * oldName,
 
 /*------------------------- Block Management and Page Allocation ----------------*/
 
-static int yaffs_InitialiseBlocks(yaffs_Device * dev, int nBlocks)
+static int yaffs_InitialiseBlocks(yaffs_Device * dev)
 {
+       int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
+       
+       dev->blockInfo = NULL;
+       dev->chunkBits = NULL;
+       
        dev->allocationBlock = -1;      /* force it to get a new one */
 
-       /* Todo we're assuming the malloc will pass. */
+       /* If the first allocation strategy fails, thry the alternate one */
        dev->blockInfo = YMALLOC(nBlocks * sizeof(yaffs_BlockInfo));
        if(!dev->blockInfo){
                dev->blockInfo = YMALLOC_ALT(nBlocks * sizeof(yaffs_BlockInfo));
@@ -1831,16 +2496,19 @@ static int yaffs_InitialiseBlocks(yaffs_Device * dev, int nBlocks)
        }
        else
                dev->blockInfoAlt = 0;
+               
+       if(dev->blockInfo){
        
-       /* Set up dynamic blockinfo stuff. */
-       dev->chunkBitmapStride = (dev->nChunksPerBlock + 7) / 8;
-       dev->chunkBits = YMALLOC(dev->chunkBitmapStride * nBlocks);
-       if(!dev->chunkBits){
-               dev->chunkBits = YMALLOC_ALT(dev->chunkBitmapStride * nBlocks);
-               dev->chunkBitsAlt = 1;
+               /* Set up dynamic blockinfo stuff. */
+               dev->chunkBitmapStride = (dev->nChunksPerBlock + 7) / 8; /* round up bytes */
+               dev->chunkBits = YMALLOC(dev->chunkBitmapStride * nBlocks);
+               if(!dev->chunkBits){
+                       dev->chunkBits = YMALLOC_ALT(dev->chunkBitmapStride * nBlocks);
+                       dev->chunkBitsAlt = 1;
+               }
+               else
+                       dev->chunkBitsAlt = 0;
        }
-       else
-               dev->chunkBitsAlt = 0;
        
        if (dev->blockInfo && dev->chunkBits) {
                memset(dev->blockInfo, 0, nBlocks * sizeof(yaffs_BlockInfo));
@@ -1854,17 +2522,18 @@ static int yaffs_InitialiseBlocks(yaffs_Device * dev, int nBlocks)
 
 static void yaffs_DeinitialiseBlocks(yaffs_Device * dev)
 {
-       if(dev->blockInfoAlt)
+       if(dev->blockInfoAlt && dev->blockInfo)
                YFREE_ALT(dev->blockInfo);
-       else
+       else if(dev->blockInfo)
                YFREE(dev->blockInfo);
+
        dev->blockInfoAlt = 0;
 
        dev->blockInfo = NULL;
        
-       if(dev->chunkBitsAlt)
+       if(dev->chunkBitsAlt && dev->chunkBits)
                YFREE_ALT(dev->chunkBits);
-       else
+       else if(dev->chunkBits)
                YFREE(dev->chunkBits);
        dev->chunkBitsAlt = 0;
        dev->chunkBits = NULL;
@@ -1906,8 +2575,6 @@ static int yaffs_BlockNotDisqualifiedFromGC(yaffs_Device * dev,
         */
        return (bi->sequenceNumber <= dev->oldestDirtySequence);
 
-       return 1;
-
 }
 
 /* FindDiretiestBlock is used to select the dirtiest block (or close enough)
@@ -1923,9 +2590,33 @@ static int yaffs_FindBlockForGarbageCollection(yaffs_Device * dev,
        int i;
        int iterations;
        int dirtiest = -1;
-       int pagesInUse;
+       int pagesInUse = 0;
+       int prioritised=0;
        yaffs_BlockInfo *bi;
-       static int nonAggressiveSkip = 0;
+       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.
@@ -1933,14 +2624,15 @@ static int yaffs_FindBlockForGarbageCollection(yaffs_Device * dev,
         * block has only a few pages in use.
         */
 
-       nonAggressiveSkip--;
+       dev->nonAggressiveSkip--;
 
-       if (!aggressive && (nonAggressiveSkip > 0)) {
+       if (!aggressive && (dev->nonAggressiveSkip > 0)) {
                return -1;
        }
 
-       pagesInUse =
-           (aggressive) ? dev->nChunksPerBlock : YAFFS_PASSIVE_GC_CHUNKS + 1;
+       if(!prioritised)
+               pagesInUse =
+                       (aggressive) ? dev->nChunksPerBlock : YAFFS_PASSIVE_GC_CHUNKS + 1;
 
        if (aggressive) {
                iterations =
@@ -1954,7 +2646,7 @@ static int yaffs_FindBlockForGarbageCollection(yaffs_Device * dev,
                }
        }
 
-       for (i = 0; i <= iterations && pagesInUse > 0; i++) {
+       for (i = 0; i <= iterations && pagesInUse > 0 && !prioritised; i++) {
                b++;
                if (b < dev->internalStartBlock || b > dev->internalEndBlock) {
                        b = dev->internalStartBlock;
@@ -1968,9 +2660,17 @@ static int yaffs_FindBlockForGarbageCollection(yaffs_Device * dev,
 
                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)) {
+                      (bi->pagesInUse - bi->softDeletions) < pagesInUse &&
+                       yaffs_BlockNotDisqualifiedFromGC(dev, bi)) {
                        dirtiest = b;
                        pagesInUse = (bi->pagesInUse - bi->softDeletions);
                }
@@ -1980,14 +2680,14 @@ static int yaffs_FindBlockForGarbageCollection(yaffs_Device * dev,
 
        if (dirtiest > 0) {
                T(YAFFS_TRACE_GC,
-                 (TSTR("GC Selected block %d with %d free" TENDSTR), dirtiest,
-                  dev->nChunksPerBlock - pagesInUse));
+                 (TSTR("GC Selected block %d with %d free, prioritised:%d" TENDSTR), dirtiest,
+                  dev->nChunksPerBlock - pagesInUse,prioritised));
        }
 
        dev->oldestDirtySequence = 0;
 
        if (dirtiest > 0) {
-               nonAggressiveSkip = 4;
+               dev->nonAggressiveSkip = 4;
        }
 
        return dirtiest;
@@ -2002,9 +2702,15 @@ static void yaffs_BlockBecameDirty(yaffs_Device * dev, int blockNo)
        /* 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++;
@@ -2013,7 +2719,8 @@ static void yaffs_BlockBecameDirty(yaffs_Device * dev, int blockNo)
                }
        }
 
-       if (erasedOk && (yaffs_traceMask & YAFFS_TRACE_ERASE)) {
+       if (erasedOk && 
+           ((yaffs_traceMask & YAFFS_TRACE_ERASE) || !yaffs_SkipVerification(dev))) {
                int i;
                for (i = 0; i < dev->nChunksPerBlock; i++) {
                        if (!yaffs_CheckChunkErased
@@ -2033,6 +2740,8 @@ static void yaffs_BlockBecameDirty(yaffs_Device * dev, int blockNo)
                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,
@@ -2095,14 +2804,24 @@ static int yaffs_FindBlockForAllocation(yaffs_Device * dev)
 }
 
 
-
+// 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 = (dev->nReservedBlocks * dev->nChunksPerBlock);
+       int reservedChunks;
+       int reservedBlocks = dev->nReservedBlocks;
+       int checkpointBlocks;
+       
+       checkpointBlocks =  dev->nCheckpointReservedBlocks - 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)
+static int yaffs_AllocateChunk(yaffs_Device * dev, int useReserve, yaffs_BlockInfo **blockUsedPtr)
 {
        int retVal;
        yaffs_BlockInfo *bi;
@@ -2143,6 +2862,9 @@ static int yaffs_AllocateChunk(yaffs_Device * dev, int useReserve)
                        dev->allocationBlock = -1;
                }
 
+               if(blockUsedPtr)
+                       *blockUsedPtr = bi;
+                       
                return retVal;
        }
        
@@ -2175,6 +2897,8 @@ static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
        int retVal = YAFFS_OK;
        int cleanups = 0;
        int i;
+       int isCheckpointBlock;
+       int matchingChunk;
 
        int chunksBefore = yaffs_GetErasedChunks(dev);
        int chunksAfter;
@@ -2185,6 +2909,8 @@ static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
 
        yaffs_Object *object;
 
+       isCheckpointBlock = (bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT);
+       
        bi->blockState = YAFFS_BLOCK_STATE_COLLECTING;
 
        T(YAFFS_TRACE_TRACING,
@@ -2202,7 +2928,8 @@ static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
 
        dev->isDoingGC = 1;
 
-       if (!yaffs_StillSomeChunkBits(dev, block)) {
+       if (isCheckpointBlock ||
+           !yaffs_StillSomeChunkBits(dev, block)) {
                T(YAFFS_TRACE_TRACING,
                  (TSTR
                   ("Collecting block %d that has no chunks in use" TENDSTR),
@@ -2211,6 +2938,8 @@ static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
        } else {
 
                __u8 *buffer = yaffs_GetTempBuffer(dev, __LINE__);
+               
+               yaffs_VerifyBlock(dev,bi,block);
 
                for (chunkInBlock = 0, oldChunk = block * dev->nChunksPerBlock;
                     chunkInBlock < dev->nChunksPerBlock
@@ -2236,12 +2965,28 @@ static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
                                   ("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 "
-                                           TENDSTR), oldChunk));
+                                          ("page %d in gc has no object: %d %d %d "
+                                           TENDSTR), oldChunk,
+                                           tags.objectId, tags.chunkId, tags.byteCount));
                                }
 
                                if (object && object->deleted
@@ -2298,6 +3043,8 @@ static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
                                                oh->shadowsObject = -1;
                                                tags.extraShadows = 0;
                                                tags.extraIsShrinkHeader = 0;
+                                               
+                                               yaffs_VerifyObjectHeader(object,oh,&tags,1);
                                        }
 
                                        newChunk =
@@ -2354,6 +3101,8 @@ static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
 
        }
 
+       yaffs_VerifyCollectedBlock(dev,bi,block);
+         
        if (chunksBefore >= (chunksAfter = yaffs_GetErasedChunks(dev))) {
                T(YAFFS_TRACE_GC,
                  (TSTR
@@ -2381,6 +3130,8 @@ static int yaffs_CheckGarbageCollection(yaffs_Device * dev)
        int aggressive;
        int gcOk = YAFFS_OK;
        int maxTries = 0;
+       
+       int checkpointBlockAdjust;
 
        if (dev->isDoingGC) {
                /* Bail out so we don't get recursive gc */
@@ -2393,7 +3144,12 @@ static int yaffs_CheckGarbageCollection(yaffs_Device * dev)
 
        do {
                maxTries++;
-               if (dev->nErasedBlocks < dev->nReservedBlocks) {
+               
+               checkpointBlockAdjust = (dev->nCheckpointReservedBlocks - dev->blocksInCheckpoint);
+               if(checkpointBlockAdjust < 0)
+                       checkpointBlockAdjust = 0;
+
+               if (dev->nErasedBlocks < (dev->nReservedBlocks + checkpointBlockAdjust + 2)) {
                        /* We need a block soon...*/
                        aggressive = 1;
                } else {
@@ -2533,7 +3289,7 @@ static int yaffs_CheckFileSanity(yaffs_Object * in)
        objId = in->objectId;
        fSize = in->variant.fileVariant.fileSize;
        nChunks =
-           (fSize + in->myDev->nBytesPerChunk - 1) / in->myDev->nBytesPerChunk;
+           (fSize + in->myDev->nDataBytesPerChunk - 1) / in->myDev->nDataBytesPerChunk;
 
        for (chunk = 1; chunk <= nChunks; chunk++) {
                tn = yaffs_FindLevel0Tnode(in->myDev, &in->variant.fileVariant,
@@ -2601,8 +3357,10 @@ static int yaffs_PutChunkIntoFile(yaffs_Object * in, int chunkInInode,
                return YAFFS_OK;
        }
 
-       tn = yaffs_AddOrFindLevel0Tnode(dev, &in->variant.fileVariant,
-                                       chunkInInode);
+       tn = yaffs_AddOrFindLevel0Tnode(dev, 
+                                       &in->variant.fileVariant,
+                                       chunkInInode,
+                                       NULL);
        if (!tn) {
                return YAFFS_FAIL;
        }
@@ -2698,13 +3456,13 @@ static int yaffs_ReadChunkDataFromObject(yaffs_Object * in, int chunkInInode,
 
        if (chunkInNAND >= 0) {
                return yaffs_ReadChunkWithTagsFromNAND(in->myDev, chunkInNAND,
-                                                      buffer, NULL);
+                                                      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->nBytesPerChunk);   
+               memset(buffer, 0, in->myDev->nDataBytesPerChunk);       
                return 0;
        }
 
@@ -2719,11 +3477,18 @@ void yaffs_DeleteChunk(yaffs_Device * dev, int chunkId, int markNAND, int lyn)
 
        if (chunkId <= 0)
                return;
+               
 
        dev->nDeletions++;
        block = chunkId / dev->nChunksPerBlock;
        page = chunkId % dev->nChunksPerBlock;
 
+
+       if(!yaffs_CheckChunkBit(dev,block,page))
+               T(YAFFS_TRACE_VERIFY,
+                       (TSTR("Deleting invalid chunk %d"TENDSTR),
+                        chunkId));
+
        bi = yaffs_GetBlockInfo(dev, block);
 
        T(YAFFS_TRACE_DELETION,
@@ -2830,18 +3595,23 @@ int yaffs_UpdateObjectHeader(yaffs_Object * in, const YCHAR * name, int force,
 
        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,"silly old name");
 
        if (!in->fake || force) {
 
                yaffs_CheckGarbageCollection(dev);
+               yaffs_CheckObjectDetailsLoaded(in);
 
                buffer = yaffs_GetTempBuffer(in->myDev, __LINE__);
                oh = (yaffs_ObjectHeader *) buffer;
@@ -2849,12 +3619,15 @@ int yaffs_UpdateObjectHeader(yaffs_Object * in, const YCHAR * name, int force,
                prevChunkId = in->chunkId;
 
                if (prevChunkId >= 0) {
-                       yaffs_ReadChunkWithTagsFromNAND(dev, prevChunkId,
-                                                       buffer, NULL);
+                       result = yaffs_ReadChunkWithTagsFromNAND(dev, prevChunkId,
+                                                       buffer, &oldTags);
+                       
+                       yaffs_VerifyObjectHeader(in,oh,&oldTags,0);
+                                                                               
                        memcpy(oldName, oh->name, sizeof(oh->name));
                }
 
-               memset(buffer, 0xFF, dev->nBytesPerChunk);
+               memset(buffer, 0xFF, dev->nDataBytesPerChunk);
 
                oh->type = in->variantType;
                oh->yst_mode = in->yst_mode;
@@ -2884,7 +3657,7 @@ int yaffs_UpdateObjectHeader(yaffs_Object * in, const YCHAR * name, int force,
                if (name && *name) {
                        memset(oh->name, 0, sizeof(oh->name));
                        yaffs_strncpy(oh->name, name, YAFFS_MAX_NAME_LENGTH);
-               } else if (prevChunkId) {
+               } else if (prevChunkId>=0) {
                        memcpy(oh->name, oldName, sizeof(oh->name));
                } else {
                        memset(oh->name, 0, sizeof(oh->name));
@@ -2938,6 +3711,8 @@ int yaffs_UpdateObjectHeader(yaffs_Object * in, const YCHAR * name, int force,
                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,
@@ -2952,7 +3727,8 @@ int yaffs_UpdateObjectHeader(yaffs_Object * in, const YCHAR * name, int force,
                                                  __LINE__);
                        }
 
-                       in->dirty = 0;
+                       if(!yaffs_ObjectHasCachedWriteData(in))
+                               in->dirty = 0;
 
                        /* If this was a shrink, then mark the block that the chunk lives on */
                        if (isShrink) {
@@ -2986,6 +3762,24 @@ int yaffs_UpdateObjectHeader(yaffs_Object * in, const YCHAR * name, int force,
  *   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;
@@ -3086,153 +3880,701 @@ static yaffs_ChunkCache *yaffs_GrabChunkCacheWorker(yaffs_Device * dev)
 
                return NULL;
 
-               theOne = -1;
-               usage = 0;      /* just to stop the compiler grizzling */
+               theOne = -1;
+               usage = 0;      /* just to stop the compiler grizzling */
+
+               for (i = 0; i < dev->nShortOpCaches; i++) {
+                       if (!dev->srCache[i].dirty &&
+                           ((dev->srCache[i].lastUse < usage && theOne >= 0) ||
+                            theOne < 0)) {
+                               usage = dev->srCache[i].lastUse;
+                               theOne = i;
+                       }
+               }
+
+
+               return theOne >= 0 ? &dev->srCache[theOne] : NULL;
+       } else {
+               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->chunkId = obj->chunkId;
+       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 void yaffs_CheckpointObjectToObject( yaffs_Object *obj,yaffs_CheckpointObject *cp)
+{
+
+       yaffs_Object *parent;
+       
+       obj->objectId = cp->objectId;
+       
+       if(cp->parentId)
+               parent = yaffs_FindOrCreateObjectByNumber(
+                                       obj->myDev,
+                                       cp->parentId,
+                                       YAFFS_OBJECT_TYPE_DIRECTORY);
+       else
+               parent = NULL;
+               
+       if(parent)
+               yaffs_AddObjectToDirectory(parent, obj);
+               
+       obj->chunkId = cp->chunkId;
+       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->objectId >= YAFFS_NOBJECT_BUCKETS)
+               obj->lazyLoaded = 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 nTnodeBytes = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
+
+       if (tn) {
+               if (level > 0) {
 
-               for (i = 0; i < dev->nShortOpCaches; i++) {
-                       if (!dev->srCache[i].dirty &&
-                           ((dev->srCache[i].lastUse < usage && theOne >= 0) ||
-                            theOne < 0)) {
-                               usage = dev->srCache[i].lastUse;
-                               theOne = i;
+                       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;
+                       /* printf("write tnode at %d\n",baseOffset); */
+                       ok = (yaffs_CheckpointWrite(dev,&baseOffset,sizeof(baseOffset)) == sizeof(baseOffset));
+                       if(ok)
+                               ok = (yaffs_CheckpointWrite(dev,tn,nTnodeBytes) == nTnodeBytes);
                }
-
-
-               return theOne >= 0 ? &dev->srCache[theOne] : NULL;
-       } else {
-               return NULL;
        }
 
+       return ok;
+
 }
 
-static yaffs_ChunkCache *yaffs_GrabChunkCache(yaffs_Device * dev)
+static int yaffs_WriteCheckpointTnodes(yaffs_Object *obj)
 {
-       yaffs_ChunkCache *cache;
-       yaffs_Object *theObj;
-       int usage;
-       int i;
-       int pushout;
-
-       if (dev->nShortOpCaches > 0) {
-               /* Try find a non-dirty one... */
+       __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;
+}
 
-               cache = yaffs_GrabChunkCacheWorker(dev);
+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;
+       
+       ok = (yaffs_CheckpointRead(dev,&baseChunk,sizeof(baseChunk)) == sizeof(baseChunk));
+       
+       while(ok && (~baseChunk)){
+               nread++;
+               /* Read level 0 tnode */
+               
+               
+               /* printf("read  tnode at %d\n",baseChunk); */
+               tn = yaffs_GetTnodeRaw(dev);
+               if(tn)
+                       ok = (yaffs_CheckpointRead(dev,tn,(dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8) ==
+                             (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
+               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));
+               
+       }
 
-               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.
-                        */
+       T(YAFFS_TRACE_CHECKPOINT,(
+               TSTR("Checkpoint read tnodes %d records, last %d. ok %d" TENDSTR),
+               nread,baseChunk,ok));
 
-                       /* With locking we can't assume we can use entry zero */
+       return ok ? 1 : 0;      
+}
 
-                       theObj = NULL;
-                       usage = -1;
-                       cache = NULL;
-                       pushout = -1;
+static int yaffs_WriteCheckpointObjects(yaffs_Device *dev)
+{
+       yaffs_Object *obj;
+       yaffs_CheckpointObject cp;
+       int i;
+       int ok = 1;
+       struct list_head *lh;
 
-                       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;
+       
+       /* Iterate through the objects in each hash entry,
+        * dumping them to the checkpointing stream.
+        */
+        
+        for(i = 0; ok &&  i <  YAFFS_NOBJECT_BUCKETS; i++){
+               list_for_each(lh, &dev->objectBucket[i].list) {
+                       if (lh) {
+                               obj = list_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.chunkId,(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;
+}
 
-                       if (!cache || cache->dirty) {
-                               /* Flush and try again */
-                               yaffs_FlushFilesChunkCache(theObj);
-                               cache = yaffs_GrabChunkCacheWorker(dev);
+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.chunkId));
+                       
+               if(ok && cp.objectId == ~0)
+                       done = 1;
+               else if(ok){
+                       obj = yaffs_FindOrCreateObjectByNumber(dev,cp.objectId, cp.variantType);
+                       if(obj) {
+                               yaffs_CheckpointObjectToObject(obj,&cp);
+                               if(obj->variantType == YAFFS_OBJECT_TYPE_FILE) {
+                                       ok = yaffs_ReadCheckpointTnodes(obj);
+                               } else if(obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
+                                       obj->hardLinks.next =
+                                                   (struct list_head *)
+                                                   hardList;
+                                       hardList = obj;
+                               }
+                          
                        }
-
                }
-               return cache;
-       } else
-               return NULL;
+       }
+       
+       if(ok)
+               yaffs_HardlinkFixup(dev,hardList);
+       
+       return ok ? 1 : 0;
+}
 
+static int yaffs_WriteCheckpointSum(yaffs_Device *dev)
+{
+       __u32 checkpointSum;
+       int ok;
+       
+       yaffs_GetCheckpointSum(dev,&checkpointSum);
+       
+       ok = (yaffs_CheckpointWrite(dev,&checkpointSum,sizeof(checkpointSum)) == sizeof(checkpointSum));
+       
+       if(!ok)
+               return 0;
+       
+       return 1;
 }
 
-/* Find a cached chunk */
-static yaffs_ChunkCache *yaffs_FindChunkCache(const yaffs_Object * obj,
-                                             int chunkId)
+static int yaffs_ReadCheckpointSum(yaffs_Device *dev)
 {
-       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++;
+       __u32 checkpointSum0;
+       __u32 checkpointSum1;
+       int ok;
+       
+       yaffs_GetCheckpointSum(dev,&checkpointSum0);
+       
+       ok = (yaffs_CheckpointRead(dev,&checkpointSum1,sizeof(checkpointSum1)) == sizeof(checkpointSum1));
+       
+       if(!ok)
+               return 0;
+               
+       if(checkpointSum0 != checkpointSum1)
+               return 0;
+       
+       return 1;
+}
 
-                               return &dev->srCache[i];
-                       }
-               }
+
+static int yaffs_WriteCheckpointData(yaffs_Device *dev)
+{
+
+       int ok = 1;
+       
+       if(dev->skipCheckpointWrite || !dev->isYaffs2){
+               T(YAFFS_TRACE_CHECKPOINT,(TSTR("skipping checkpoint write" TENDSTR)));
+               ok = 0;
        }
-       return NULL;
+               
+       if(ok)
+               ok = yaffs_CheckpointOpen(dev,1);
+       
+       if(ok){
+               T(YAFFS_TRACE_CHECKPOINT,(TSTR("write checkpoint validity" TENDSTR)));
+               ok = yaffs_WriteCheckpointValidityMarker(dev,1);
+       }
+       if(ok){
+               T(YAFFS_TRACE_CHECKPOINT,(TSTR("write checkpoint device" TENDSTR)));
+               ok = yaffs_WriteCheckpointDevice(dev);
+       }
+       if(ok){
+               T(YAFFS_TRACE_CHECKPOINT,(TSTR("write checkpoint objects" TENDSTR)));
+               ok = yaffs_WriteCheckpointObjects(dev);
+       }
+       if(ok){
+               T(YAFFS_TRACE_CHECKPOINT,(TSTR("write checkpoint validity" TENDSTR)));
+               ok = yaffs_WriteCheckpointValidityMarker(dev,0);
+       }
+       
+       if(ok){
+               ok = yaffs_WriteCheckpointSum(dev);
+       }
+       
+       
+       if(!yaffs_CheckpointClose(dev))
+                ok = 0;
+                
+       if(ok)
+               dev->isCheckpointed = 1;
+        else 
+               dev->isCheckpointed = 0;
+
+       return dev->isCheckpointed;
 }
 
-/* Mark the chunk for the least recently used algorithym */
-static void yaffs_UseChunkCache(yaffs_Device * dev, yaffs_ChunkCache * cache,
-                               int isAWrite)
+static int yaffs_ReadCheckpointData(yaffs_Device *dev)
 {
+       int ok = 1;
+       
+       if(dev->skipCheckpointRead || !dev->isYaffs2){
+               T(YAFFS_TRACE_CHECKPOINT,(TSTR("skipping checkpoint read" TENDSTR)));
+               ok = 0;
+       }
+       
+       if(ok)
+               ok = yaffs_CheckpointOpen(dev,0); /* open for read */
+       
+       if(ok){
+               T(YAFFS_TRACE_CHECKPOINT,(TSTR("read checkpoint validity" TENDSTR)));   
+               ok = yaffs_ReadCheckpointValidityMarker(dev,1);
+       }
+       if(ok){
+               T(YAFFS_TRACE_CHECKPOINT,(TSTR("read checkpoint device" TENDSTR)));
+               ok = yaffs_ReadCheckpointDevice(dev);
+       }
+       if(ok){
+               T(YAFFS_TRACE_CHECKPOINT,(TSTR("read checkpoint objects" TENDSTR)));    
+               ok = yaffs_ReadCheckpointObjects(dev);
+       }
+       if(ok){
+               T(YAFFS_TRACE_CHECKPOINT,(TSTR("read checkpoint validity" TENDSTR)));
+               ok = yaffs_ReadCheckpointValidityMarker(dev,0);
+       }
+       
+       if(ok){
+               ok = yaffs_ReadCheckpointSum(dev);
+               T(YAFFS_TRACE_CHECKPOINT,(TSTR("read checkpoint checksum %d" TENDSTR),ok));
+       }
 
-       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;
-               }
+       if(!yaffs_CheckpointClose(dev))
+               ok = 0;
 
-               dev->srLastUse++;
+       if(ok)
+               dev->isCheckpointed = 1;
+        else 
+               dev->isCheckpointed = 0;
 
-               cache->lastUse = dev->srLastUse;
+       return ok ? 1 : 0;
 
-               if (isAWrite) {
-                       cache->dirty = 1;
-               }
+}
+
+static void yaffs_InvalidateCheckpoint(yaffs_Device *dev)
+{
+       if(dev->isCheckpointed || 
+          dev->blocksInCheckpoint > 0){
+               dev->isCheckpointed = 0;
+               yaffs_CheckpointInvalidateStream(dev);
+               if(dev->superBlock && dev->markSuperBlockDirty)
+                       dev->markSuperBlockDirty(dev->superBlock);
        }
 }
 
-/* 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)
+
+int yaffs_CheckpointSave(yaffs_Device *dev)
 {
-       if (object->myDev->nShortOpCaches > 0) {
-               yaffs_ChunkCache *cache = yaffs_FindChunkCache(object, chunkId);
 
-               if (cache) {
-                       cache->object = NULL;
-               }
+       T(YAFFS_TRACE_CHECKPOINT,(TSTR("save entry: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
+
+       yaffs_VerifyObjects(dev);
+       yaffs_VerifyBlocks(dev);
+       yaffs_VerifyFreeChunks(dev);
+
+       if(!dev->isCheckpointed) {
+               yaffs_InvalidateCheckpoint(dev);
+               yaffs_WriteCheckpointData(dev);
        }
+       
+       T(YAFFS_TRACE_ALWAYS,(TSTR("save exit: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
+
+       return dev->isCheckpointed;
 }
 
-/* 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 yaffs_CheckpointRestore(yaffs_Device *dev)
 {
-       int i;
-       yaffs_Device *dev = in->myDev;
+       int retval;
+       T(YAFFS_TRACE_CHECKPOINT,(TSTR("restore entry: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
+               
+       retval = yaffs_ReadCheckpointData(dev);
 
-       if (dev->nShortOpCaches > 0) {
-               /* Invalidate it. */
-               for (i = 0; i < dev->nShortOpCaches; i++) {
-                       if (dev->srCache[i].object == in) {
-                               dev->srCache[i].object = NULL;
-                       }
-               }
+       if(dev->isCheckpointed){
+               yaffs_VerifyObjects(dev);
+               yaffs_VerifyBlocks(dev);
+               yaffs_VerifyFreeChunks(dev);
        }
+
+       T(YAFFS_TRACE_CHECKPOINT,(TSTR("restore exit: isCheckpointed %d"TENDSTR),dev->isCheckpointed));
+       
+       return retval;
 }
 
 /*--------------------- File read/write ------------------------
@@ -3245,7 +4587,7 @@ static void yaffs_InvalidateWholeChunkCache(yaffs_Object * in)
  * Curve-balls: the first chunk might also be the last chunk.
  */
 
-int yaffs_ReadDataFromFile(yaffs_Object * in, __u8 * buffer, __u32 offset,
+int yaffs_ReadDataFromFile(yaffs_Object * in, __u8 * buffer, loff_t offset,
                           int nBytes)
 {
 
@@ -3261,16 +4603,18 @@ int yaffs_ReadDataFromFile(yaffs_Object * in, __u8 * buffer, __u32 offset,
        dev = in->myDev;
 
        while (n > 0) {
-               chunk = offset / dev->nBytesPerChunk + 1;   /* The first chunk is 1 */
-               start = offset % dev->nBytesPerChunk;
+               //chunk = offset / dev->nDataBytesPerChunk + 1;
+               //start = offset % dev->nDataBytesPerChunk;
+               yaffs_AddrToChunk(dev,offset,&chunk,&start);
+               chunk++;
 
                /* OK now check for the curveball where the start and end are in
                 * the same chunk.      
                 */
-               if ((start + n) < dev->nBytesPerChunk) {
+               if ((start + n) < dev->nDataBytesPerChunk) {
                        nToCopy = n;
                } else {
-                       nToCopy = dev->nBytesPerChunk - start;
+                       nToCopy = dev->nDataBytesPerChunk - start;
                }
 
                cache = yaffs_FindChunkCache(in, chunk);
@@ -3279,7 +4623,7 @@ int yaffs_ReadDataFromFile(yaffs_Object * in, __u8 * buffer, __u32 offset,
                 * then use the cache (if there is caching)
                 * else bypass the cache.
                 */
-               if (cache || nToCopy != dev->nBytesPerChunk) {
+               if (cache || nToCopy != dev->nDataBytesPerChunk) {
                        if (dev->nShortOpCaches > 0) {
 
                                /* If we can't find the data in the cache, then load it up. */
@@ -3340,7 +4684,7 @@ int yaffs_ReadDataFromFile(yaffs_Object * in, __u8 * buffer, __u32 offset,
 #ifdef CONFIG_YAFFS_WINCE
                        yfsd_UnlockYAFFS(TRUE);
 #endif
-                       memcpy(buffer, localBuffer, dev->nBytesPerChunk);
+                       memcpy(buffer, localBuffer, dev->nDataBytesPerChunk);
 
 #ifdef CONFIG_YAFFS_WINCE
                        yfsd_LockYAFFS(TRUE);
@@ -3363,7 +4707,7 @@ int yaffs_ReadDataFromFile(yaffs_Object * in, __u8 * buffer, __u32 offset,
        return nDone;
 }
 
-int yaffs_WriteDataToFile(yaffs_Object * in, const __u8 * buffer, __u32 offset,
+int yaffs_WriteDataToFile(yaffs_Object * in, const __u8 * buffer, loff_t offset,
                          int nBytes, int writeThrough)
 {
 
@@ -3382,14 +4726,16 @@ int yaffs_WriteDataToFile(yaffs_Object * in, const __u8 * buffer, __u32 offset,
        dev = in->myDev;
 
        while (n > 0 && chunkWritten >= 0) {
-               chunk = offset / dev->nBytesPerChunk + 1;
-               start = offset % dev->nBytesPerChunk;
+               //chunk = offset / dev->nDataBytesPerChunk + 1;
+               //start = offset % dev->nDataBytesPerChunk;
+               yaffs_AddrToChunk(dev,offset,&chunk,&start);
+               chunk++;
 
                /* OK now check for the curveball where the start and end are in
                 * the same chunk.
                 */
 
-               if ((start + n) < dev->nBytesPerChunk) {
+               if ((start + n) < dev->nDataBytesPerChunk) {
                        nToCopy = n;
 
                        /* Now folks, to calculate how many bytes to write back....
@@ -3399,10 +4745,10 @@ int yaffs_WriteDataToFile(yaffs_Object * in, const __u8 * buffer, __u32 offset,
 
                        nBytesRead =
                            in->variant.fileVariant.fileSize -
-                           ((chunk - 1) * dev->nBytesPerChunk);
+                           ((chunk - 1) * dev->nDataBytesPerChunk);
 
-                       if (nBytesRead > dev->nBytesPerChunk) {
-                               nBytesRead = dev->nBytesPerChunk;
+                       if (nBytesRead > dev->nDataBytesPerChunk) {
+                               nBytesRead = dev->nDataBytesPerChunk;
                        }
 
                        nToWriteBack =
@@ -3410,16 +4756,17 @@ int yaffs_WriteDataToFile(yaffs_Object * in, const __u8 * buffer, __u32 offset,
                             (start + n)) ? nBytesRead : (start + n);
 
                } else {
-                       nToCopy = dev->nBytesPerChunk - start;
-                       nToWriteBack = dev->nBytesPerChunk;
+                       nToCopy = dev->nDataBytesPerChunk - start;
+                       nToWriteBack = dev->nDataBytesPerChunk;
                }
 
-               if (nToCopy != dev->nBytesPerChunk) {
+               if (nToCopy != dev->nDataBytesPerChunk) {
                        /* An incomplete start or end chunk (or maybe both start and end chunk) */
                        if (dev->nShortOpCaches > 0) {
                                yaffs_ChunkCache *cache;
                                /* If we can't find the data in the cache, then load the cache */
                                cache = yaffs_FindChunkCache(in, chunk);
+                               
                                if (!cache
                                    && yaffs_CheckSpaceForAllocation(in->
                                                                     myDev)) {
@@ -3432,6 +4779,14 @@ int yaffs_WriteDataToFile(yaffs_Object * in, const __u8 * buffer, __u32 offset,
                                                                      cache->
                                                                      data);
                                }
+                               else if(cache && 
+                                       !cache->dirty &&
+                                       !yaffs_CheckSpaceForAllocation(in->myDev)){
+                                       /* Drop the cache if it was a read cache item and
+                                        * no space check has been made for it.
+                                        */ 
+                                        cache = NULL;
+                               }
 
                                if (cache) {
                                        yaffs_UseChunkCache(dev, cache, 1);
@@ -3503,20 +4858,20 @@ int yaffs_WriteDataToFile(yaffs_Object * in, const __u8 * buffer, __u32 offset,
 #ifdef CONFIG_YAFFS_WINCE
                        yfsd_UnlockYAFFS(TRUE);
 #endif
-                       memcpy(localBuffer, buffer, dev->nBytesPerChunk);
+                       memcpy(localBuffer, buffer, dev->nDataBytesPerChunk);
 #ifdef CONFIG_YAFFS_WINCE
                        yfsd_LockYAFFS(TRUE);
 #endif
                        chunkWritten =
                            yaffs_WriteChunkDataToObject(in, chunk, localBuffer,
-                                                        dev->nBytesPerChunk,
+                                                        dev->nDataBytesPerChunk,
                                                         0);
                        yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
 #else
                        /* A full chunk. Write directly from the supplied buffer. */
                        chunkWritten =
                            yaffs_WriteChunkDataToObject(in, chunk, buffer,
-                                                        dev->nBytesPerChunk,
+                                                        dev->nDataBytesPerChunk,
                                                         0);
 #endif
                        /* Since we've overwritten the cached data, we better invalidate it. */
@@ -3552,10 +4907,10 @@ static void yaffs_PruneResizedChunks(yaffs_Object * in, int newSize)
        yaffs_Device *dev = in->myDev;
        int oldFileSize = in->variant.fileVariant.fileSize;
 
-       int lastDel = 1 + (oldFileSize - 1) / dev->nBytesPerChunk;
+       int lastDel = 1 + (oldFileSize - 1) / dev->nDataBytesPerChunk;
 
-       int startDel = 1 + (newSize + dev->nBytesPerChunk - 1) /
-           dev->nBytesPerChunk;
+       int startDel = 1 + (newSize + dev->nDataBytesPerChunk - 1) /
+           dev->nDataBytesPerChunk;
        int i;
        int chunkId;
 
@@ -3587,14 +4942,16 @@ static void yaffs_PruneResizedChunks(yaffs_Object * in, int newSize)
 
 }
 
-int yaffs_ResizeFile(yaffs_Object * in, int newSize)
+int yaffs_ResizeFile(yaffs_Object * in, loff_t newSize)
 {
 
        int oldFileSize = in->variant.fileVariant.fileSize;
-       int sizeOfPartialChunk;
+       int newSizeOfPartialChunk;
+       int newFullChunks;
+       
        yaffs_Device *dev = in->myDev;
 
-       sizeOfPartialChunk = newSize % dev->nBytesPerChunk;
+       yaffs_AddrToChunk(dev, newSize, &newFullChunks, &newSizeOfPartialChunk);
 
        yaffs_FlushFilesChunkCache(in);
        yaffs_InvalidateWholeChunkCache(in);
@@ -3613,19 +4970,20 @@ int yaffs_ResizeFile(yaffs_Object * in, int newSize)
 
                yaffs_PruneResizedChunks(in, newSize);
 
-               if (sizeOfPartialChunk != 0) {
-                       int lastChunk = 1 + newSize / dev->nBytesPerChunk;
+               if (newSizeOfPartialChunk != 0) {
+                       int lastChunk = 1 + newFullChunks;
+                       
                        __u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
 
                        /* Got to read and rewrite the last chunk with its new size and zero pad */
                        yaffs_ReadChunkDataFromObject(in, lastChunk,
                                                      localBuffer);
 
-                       memset(localBuffer + sizeOfPartialChunk, 0,
-                              dev->nBytesPerChunk - sizeOfPartialChunk);
+                       memset(localBuffer + newSizeOfPartialChunk, 0,
+                              dev->nDataBytesPerChunk - newSizeOfPartialChunk);
 
                        yaffs_WriteChunkDataToObject(in, lastChunk, localBuffer,
-                                                    sizeOfPartialChunk, 1);
+                                                    newSizeOfPartialChunk, 1);
 
                        yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
                }
@@ -3633,7 +4991,13 @@ int yaffs_ResizeFile(yaffs_Object * in, int newSize)
                in->variant.fileVariant.fileSize = newSize;
 
                yaffs_PruneFileStructure(dev, &in->variant.fileVariant);
+       } else {
+               /* newsSize > oldFileSize */
+               in->variant.fileVariant.fileSize = newSize;
        }
+
+               
+       
        /* Write a new object header.
         * show we've shrunk the file, if need be
         * Do this only if the file is not in the deleted directories.
@@ -3644,7 +5008,7 @@ int yaffs_ResizeFile(yaffs_Object * in, int newSize)
                                         (newSize < oldFileSize) ? 1 : 0, 0);
        }
 
-       return newSize;
+       return YAFFS_OK;
 }
 
 loff_t yaffs_GetFileSize(yaffs_Object * obj)
@@ -3697,7 +5061,7 @@ static int yaffs_DoGenericObjectDeletion(yaffs_Object * in)
 
        if (in->myDev->isYaffs2 && (in->parent != in->myDev->deletedDir)) {
                /* Move to the unlinked directory so we have a record that it was deleted. */
-               yaffs_ChangeObjectName(in, in->myDev->deletedDir, NULL, 0, 0);
+               yaffs_ChangeObjectName(in, in->myDev->deletedDir,"deleted", 0, 0);
 
        }
 
@@ -3735,7 +5099,7 @@ static int yaffs_UnlinkFile(yaffs_Object * in)
                if (immediateDeletion) {
                        retVal =
                            yaffs_ChangeObjectName(in, in->myDev->deletedDir,
-                                                  NULL, 0, 0);
+                                                  "deleted", 0, 0);
                        T(YAFFS_TRACE_TRACING,
                          (TSTR("yaffs: immediate deletion of file %d" TENDSTR),
                           in->objectId));
@@ -3748,7 +5112,7 @@ static int yaffs_UnlinkFile(yaffs_Object * in)
                } else {
                        retVal =
                            yaffs_ChangeObjectName(in, in->myDev->unlinkedDir,
-                                                  NULL, 0, 0);
+                                                  "unlinked", 0, 0);
                }
 
        }
@@ -3947,6 +5311,53 @@ typedef struct {
        int block;
 } yaffs_BlockIndex;
 
+
+static void yaffs_HardlinkFixup(yaffs_Device *dev, yaffs_Object *hardList)
+{
+       yaffs_Object *hl;
+       yaffs_Object *in;
+       
+       while (hardList) {
+               hl = hardList;
+               hardList = (yaffs_Object *) (hardList->hardLinks.next);
+
+               in = yaffs_FindObjectByNumber(dev,
+                                             hl->variant.hardLinkVariant.
+                                             equivalentObjectId);
+
+               if (in) {
+                       /* Add the hardlink pointers */
+                       hl->variant.hardLinkVariant.equivalentObject = in;
+                       list_add(&hl->hardLinks, &in->hardLinks);
+               } else {
+                       /* Todo Need to report/handle this better.
+                        * Got a problem... hardlink to a non-existant object
+                        */
+                       hl->variant.hardLinkVariant.equivalentObject = NULL;
+                       INIT_LIST_HEAD(&hl->hardLinks);
+
+               }
+
+       }
+
+}
+
+
+
+
+
+static int ybicmp(const void *a, const void *b){
+    register int aseq = ((yaffs_BlockIndex *)a)->seq;
+    register int bseq = ((yaffs_BlockIndex *)b)->seq;
+    register int ablock = ((yaffs_BlockIndex *)a)->block;
+    register int bblock = ((yaffs_BlockIndex *)b)->block;
+    if( aseq == bseq )
+        return ablock - bblock;
+    else
+        return aseq - bseq;
+
+}
+
 static int yaffs_Scan(yaffs_Device * dev)
 {
        yaffs_ExtendedTags tags;
@@ -3955,24 +5366,35 @@ static int yaffs_Scan(yaffs_Device * dev)
        int startIterator;
        int endIterator;
        int nBlocksToScan = 0;
+       int result;
 
        int chunk;
        int c;
        int deleted;
        yaffs_BlockState state;
        yaffs_Object *hardList = NULL;
-       yaffs_Object *hl;
        yaffs_BlockInfo *bi;
        int sequenceNumber;
        yaffs_ObjectHeader *oh;
        yaffs_Object *in;
        yaffs_Object *parent;
        int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
+       
+       int alloc_failed = 0;
+       
 
        __u8 *chunkData;
 
        yaffs_BlockIndex *blockIndex = NULL;
 
+       if (dev->isYaffs2) {
+               T(YAFFS_TRACE_SCAN,
+                 (TSTR("yaffs_Scan is not for YAFFS2!" TENDSTR)));
+               return YAFFS_FAIL;
+       }
+       
+       //TODO  Throw all the yaffs2 stuuf out of yaffs_Scan since it is only for yaffs1 format.
+       
        T(YAFFS_TRACE_SCAN,
          (TSTR("yaffs_Scan starts  intstartblk %d intendblk %d..." TENDSTR),
           dev->internalStartBlock, dev->internalEndBlock));
@@ -3983,6 +5405,8 @@ static int yaffs_Scan(yaffs_Device * dev)
 
        if (dev->isYaffs2) {
                blockIndex = YMALLOC(nBlocks * sizeof(yaffs_BlockIndex));
+               if(!blockIndex)
+                       return YAFFS_FAIL;
        }
 
        /* Scan all the blocks to determine their state */
@@ -4064,7 +5488,7 @@ static int yaffs_Scan(yaffs_Device * dev)
        }
 
        /* For each block.... */
-       for (blockIterator = startIterator; blockIterator <= endIterator;
+       for (blockIterator = startIterator; !alloc_failed && blockIterator <= endIterator;
             blockIterator++) {
 
                if (dev->isYaffs2) {
@@ -4080,12 +5504,12 @@ static int yaffs_Scan(yaffs_Device * dev)
                deleted = 0;
 
                /* For each chunk in each block that needs scanning....*/
-               for (c = 0; c < dev->nChunksPerBlock &&
+               for (c = 0; !alloc_failed && c < dev->nChunksPerBlock &&
                     state == YAFFS_BLOCK_STATE_NEEDS_SCANNING; c++) {
                        /* Read the tags and decide what to do */
                        chunk = blk * dev->nChunksPerBlock + c;
 
-                       yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
+                       result = yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
                                                        &tags);
 
                        /* Let's have a good look at this chunk... */
@@ -4148,12 +5572,20 @@ static int yaffs_Scan(yaffs_Device * dev)
                                /* PutChunkIntoFile checks for a clash (two data chunks with
                                 * the same chunkId).
                                 */
-                               yaffs_PutChunkIntoFile(in, tags.chunkId, chunk,
-                                                      1);
+                                
+                               if(!in)
+                                       alloc_failed = 1;
+
+                               if(in){
+                                       if(!yaffs_PutChunkIntoFile(in, tags.chunkId, chunk,1))
+                                               alloc_failed = 1;
+                               }
+                               
                                endpos =
-                                   (tags.chunkId - 1) * dev->nBytesPerChunk +
+                                   (tags.chunkId - 1) * dev->nDataBytesPerChunk +
                                    tags.byteCount;
-                               if (in->variantType == YAFFS_OBJECT_TYPE_FILE
+                               if (in && 
+                                   in->variantType == YAFFS_OBJECT_TYPE_FILE
                                    && in->variant.fileVariant.scannedFileSize <
                                    endpos) {
                                        in->variant.fileVariant.
@@ -4174,7 +5606,7 @@ static int yaffs_Scan(yaffs_Device * dev)
                                yaffs_SetChunkBit(dev, blk, c);
                                bi->pagesInUse++;
 
-                               yaffs_ReadChunkWithTagsFromNAND(dev, chunk,
+                               result = yaffs_ReadChunkWithTagsFromNAND(dev, chunk,
                                                                chunkData,
                                                                NULL);
 
@@ -4198,14 +5630,17 @@ static int yaffs_Scan(yaffs_Device * dev)
                                                                      objectId,
                                                                      oh->type);
 
-                               if (oh->shadowsObject > 0) {
+                               if(!in)
+                                       alloc_failed = 1;
+                                       
+                               if (in && oh->shadowsObject > 0) {
                                        yaffs_HandleShadowedObject(dev,
                                                                   oh->
                                                                   shadowsObject,
                                                                   0);
                                }
 
-                               if (in->valid) {
+                               if (in && in->valid) {
                                        /* We have already filled this one. We have a duplicate and need to resolve it. */
 
                                        unsigned existingSerial = in->serial;
@@ -4226,7 +5661,7 @@ static int yaffs_Scan(yaffs_Device * dev)
                                        }
                                }
 
-                               if (!in->valid &&
+                               if (in && !in->valid &&
                                    (tags.objectId == YAFFS_OBJECTID_ROOT ||
                                     tags.objectId == YAFFS_OBJECTID_LOSTNFOUND)) {
                                        /* We only load some info, don't fiddle with directory structure */
@@ -4251,7 +5686,7 @@ static int yaffs_Scan(yaffs_Device * dev)
 #endif
                                        in->chunkId = chunk;
 
-                               } else if (!in->valid) {
+                               } else if (in && !in->valid) {
                                        /* we need to load this info */
 
                                        in->valid = 1;
@@ -4360,9 +5795,10 @@ static int yaffs_Scan(yaffs_Device * dev)
                                                /* Do nothing */
                                                break;
                                        case YAFFS_OBJECT_TYPE_SYMLINK: 
-                                               in->variant.symLinkVariant.
-                                                   alias =
+                                               in->variant.symLinkVariant.alias =
                                                    yaffs_CloneString(oh->alias);
+                                               if(!in->variant.symLinkVariant.alias)
+                                                       alloc_failed = 1;
                                                break;
                                        }
 
@@ -4394,33 +5830,14 @@ static int yaffs_Scan(yaffs_Device * dev)
                YFREE(blockIndex);
        }
        
+       
        /* Ok, we've done all the scanning.
         * Fix up the hard link chains.
         * We should now have scanned all the objects, now it's time to add these 
         * hardlinks.
         */
-       while (hardList) {
-               hl = hardList;
-               hardList = (yaffs_Object *) (hardList->hardLinks.next);
-
-               in = yaffs_FindObjectByNumber(dev,
-                                             hl->variant.hardLinkVariant.
-                                             equivalentObjectId);
-
-               if (in) {
-                       /* Add the hardlink pointers */
-                       hl->variant.hardLinkVariant.equivalentObject = in;
-                       list_add(&hl->hardLinks, &in->hardLinks);
-               } else {
-                       /* Todo Need to report/handle this better.
-                        * Got a problem... hardlink to a non-existant object
-                        */
-                       hl->variant.hardLinkVariant.equivalentObject = NULL;
-                       INIT_LIST_HEAD(&hl->hardLinks);
 
-               }
-
-       }
+       yaffs_HardlinkFixup(dev,hardList);
 
        /* Handle the unlinked files. Since they were left in an unlinked state we should
         * just delete them.
@@ -4443,7 +5860,12 @@ static int yaffs_Scan(yaffs_Device * dev)
 
        yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
 
+       if(alloc_failed){
+               return YAFFS_FAIL;
+       }
+       
        T(YAFFS_TRACE_SCAN, (TSTR("yaffs_Scan ends" TENDSTR)));
+       
 
        return YAFFS_OK;
 }
@@ -4453,12 +5875,24 @@ static void yaffs_CheckObjectDetailsLoaded(yaffs_Object *in)
        __u8 *chunkData;
        yaffs_ObjectHeader *oh;
        yaffs_Device *dev = in->myDev;
-       
+       yaffs_ExtendedTags tags;
+       int result;
+       int alloc_failed = 0;
+
+       if(!in)
+               return;
+               
+#if 0
+       T(YAFFS_TRACE_SCAN,(TSTR("details for object %d %s loaded" TENDSTR),
+               in->objectId,
+               in->lazyLoaded ? "not yet" : "already"));
+#endif
+
        if(in->lazyLoaded){
                in->lazyLoaded = 0;
                chunkData = yaffs_GetTempBuffer(dev, __LINE__);
 
-               yaffs_ReadChunkWithTagsFromNAND(dev,in->chunkId,chunkData,NULL);
+               result = yaffs_ReadChunkWithTagsFromNAND(dev,in->chunkId,chunkData,&tags);
                oh = (yaffs_ObjectHeader *) chunkData;          
 
                in->yst_mode = oh->yst_mode;
@@ -4480,9 +5914,12 @@ static void yaffs_CheckObjectDetailsLoaded(yaffs_Object *in)
 #endif
                yaffs_SetObjectName(in, oh->name);
                
-               if(in->variantType == YAFFS_OBJECT_TYPE_SYMLINK)
+               if(in->variantType == YAFFS_OBJECT_TYPE_SYMLINK){
                         in->variant.symLinkVariant.alias =
                                                    yaffs_CloneString(oh->alias);
+                       if(!in->variant.symLinkVariant.alias)
+                               alloc_failed = 1; /* Not returned to caller */
+               }
                                                    
                yaffs_ReleaseTempBuffer(dev,chunkData, __LINE__);
        }
@@ -4498,11 +5935,11 @@ static int yaffs_ScanBackwards(yaffs_Device * dev)
        int nBlocksToScan = 0;
 
        int chunk;
+       int result;
        int c;
        int deleted;
        yaffs_BlockState state;
        yaffs_Object *hardList = NULL;
-       yaffs_Object *hl;
        yaffs_BlockInfo *bi;
        int sequenceNumber;
        yaffs_ObjectHeader *oh;
@@ -4514,10 +5951,13 @@ static int yaffs_ScanBackwards(yaffs_Device * dev)
        
        int fileSize;
        int isShrink;
+       int foundChunksInBlock;
        int equivalentObjectId;
+       int alloc_failed = 0;
        
 
        yaffs_BlockIndex *blockIndex = NULL;
+       int altBlockIndex = 0;
 
        if (!dev->isYaffs2) {
                T(YAFFS_TRACE_SCAN,
@@ -4530,11 +5970,25 @@ static int yaffs_ScanBackwards(yaffs_Device * dev)
           ("yaffs_ScanBackwards starts  intstartblk %d intendblk %d..."
            TENDSTR), dev->internalStartBlock, dev->internalEndBlock));
 
-       chunkData = yaffs_GetTempBuffer(dev, __LINE__);
 
        dev->sequenceNumber = YAFFS_LOWEST_SEQUENCE_NUMBER;
 
        blockIndex = YMALLOC(nBlocks * sizeof(yaffs_BlockIndex));
+       
+       if(!blockIndex) {
+               blockIndex = YMALLOC_ALT(nBlocks * sizeof(yaffs_BlockIndex));
+               altBlockIndex = 1;
+       }
+       
+       if(!blockIndex) {
+               T(YAFFS_TRACE_SCAN,
+                 (TSTR("yaffs_Scan() could not allocate block index!" TENDSTR)));
+               return YAFFS_FAIL;
+       }
+       
+       dev->blocksInCheckpoint = 0;
+       
+       chunkData = yaffs_GetTempBuffer(dev, __LINE__);
 
        /* Scan all the blocks to determine their state */
        for (blk = dev->internalStartBlock; blk <= dev->internalEndBlock; blk++) {
@@ -4548,11 +6002,18 @@ static int yaffs_ScanBackwards(yaffs_Device * dev)
                bi->blockState = state;
                bi->sequenceNumber = sequenceNumber;
 
+               if(bi->sequenceNumber == YAFFS_SEQUENCE_CHECKPOINT_DATA)
+                       bi->blockState = state = YAFFS_BLOCK_STATE_CHECKPOINT;
+                       
                T(YAFFS_TRACE_SCAN_DEBUG,
                  (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
                   state, sequenceNumber));
 
-               if (state == YAFFS_BLOCK_STATE_DEAD) {
+               
+               if(state == YAFFS_BLOCK_STATE_CHECKPOINT){
+                       dev->blocksInCheckpoint++;
+                       
+               } else if (state == YAFFS_BLOCK_STATE_DEAD) {
                        T(YAFFS_TRACE_BAD_BLOCKS,
                          (TSTR("block %d is bad" TENDSTR), blk));
                } else if (state == YAFFS_BLOCK_STATE_EMPTY) {
@@ -4586,11 +6047,23 @@ static int yaffs_ScanBackwards(yaffs_Device * dev)
                }
        }
 
-       /*
-        * Sort the blocks
-        * Dungy old bubble sort for now...
-        */
+       T(YAFFS_TRACE_SCAN,
+       (TSTR("%d blocks to be sorted..." TENDSTR), nBlocksToScan));
+
+
+
+       YYIELD();
+
+       /* Sort the blocks */
+#ifndef CONFIG_YAFFS_USE_OWN_SORT
+       {
+               /* Use qsort now. */
+               yaffs_qsort(blockIndex, nBlocksToScan, sizeof(yaffs_BlockIndex), ybicmp);
+       }
+#else
        {
+               /* Dungy old bubble sort... */
+               
                yaffs_BlockIndex temp;
                int i;
                int j;
@@ -4603,6 +6076,11 @@ static int yaffs_ScanBackwards(yaffs_Device * dev)
                                        blockIndex[i] = temp;
                                }
        }
+#endif
+
+       YYIELD();
+
+       T(YAFFS_TRACE_SCAN, (TSTR("...done" TENDSTR)));
 
        /* Now scan the blocks looking at the data. */
        startIterator = 0;
@@ -4611,80 +6089,101 @@ static int yaffs_ScanBackwards(yaffs_Device * dev)
          (TSTR("%d blocks to be scanned" TENDSTR), nBlocksToScan));
 
        /* For each block.... backwards */
-       for (blockIterator = endIterator; blockIterator >= startIterator;
+       for (blockIterator = endIterator; !alloc_failed && blockIterator >= startIterator;
             blockIterator--) {
+               /* Cooperative multitasking! This loop can run for so
+                  long that watchdog timers expire. */
+               YYIELD();
 
                /* get the block to scan in the correct order */
                blk = blockIndex[blockIterator].block;
 
                bi = yaffs_GetBlockInfo(dev, blk);
+               
+               
                state = bi->blockState;
 
                deleted = 0;
 
                /* For each chunk in each block that needs scanning.... */
-               for (c = dev->nChunksPerBlock - 1; c >= 0 &&
+               foundChunksInBlock = 0;
+               for (c = dev->nChunksPerBlock - 1; 
+                    !alloc_failed && c >= 0 &&
                     (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
                      state == YAFFS_BLOCK_STATE_ALLOCATING); c--) {
                        /* Scan backwards... 
                         * Read the tags and decide what to do
                         */
+                       
                        chunk = blk * dev->nChunksPerBlock + c;
 
-                       yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
+                       result = yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
                                                        &tags);
 
                        /* Let's have a good look at this chunk... */
 
                        if (!tags.chunkUsed) {
-                               // An unassigned chunk in the block
-                               // This means that either the block is empty or 
-                               // this is the one being allocated from
+                               /* An unassigned chunk in the block.
+                                * If there are used chunks after this one, then
+                                * it is a chunk that was skipped due to failing the erased
+                                * check. Just skip it so that it can be deleted.
+                                * But, more typically, We get here when this is an unallocated
+                                * chunk and his means that either the block is empty or 
+                                * this is the one being allocated from
+                                */
 
-                               if (c == 0) {
+                               if(foundChunksInBlock)
+                               {
+                                       /* This is a chunk that was skipped due to failing the erased check */
+                                       
+                               } else if (c == 0) {
                                        /* We're looking at the first chunk in the block so the block is unused */
                                        state = YAFFS_BLOCK_STATE_EMPTY;
                                        dev->nErasedBlocks++;
                                } else {
-                                       /* this is the block being allocated from */
-                                       if (state ==
-                                           YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
-                                               T(YAFFS_TRACE_SCAN,
-                                                 (TSTR
-                                                  (" Allocating from %d %d"
-                                                   TENDSTR), blk, c));
+                                       if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
+                                           state == YAFFS_BLOCK_STATE_ALLOCATING) {
+                                               if(dev->sequenceNumber == bi->sequenceNumber) {
+                                                       /* this is the block being allocated from */
+                                               
+                                                       T(YAFFS_TRACE_SCAN,
+                                                         (TSTR
+                                                          (" Allocating from %d %d"
+                                                           TENDSTR), blk, c));
+
+                                                       state = YAFFS_BLOCK_STATE_ALLOCATING;
+                                                       dev->allocationBlock = blk;
+                                                       dev->allocationPage = c;
+                                                       dev->allocationBlockFinder = blk;       
+                                               }
+                                               else {
+                                                       /* This is a partially written block that is not
+                                                        * the current allocation block. This block must have
+                                                        * had a write failure, so set up for retirement.
+                                                        */
+                                                 
+                                                        bi->needsRetiring = 1;
+                                                        bi->gcPrioritise = 1;
+                                                                                                        
+                                                        T(YAFFS_TRACE_ALWAYS,
+                                                        (TSTR("Partially written block %d being set for retirement" TENDSTR),
+                                                        blk));
+                                               }
+
                                        }
-                                       state = YAFFS_BLOCK_STATE_ALLOCATING;
-                                       dev->allocationBlock = blk;
-                                       dev->allocationPage = c;
-                                       dev->allocationBlockFinder = blk;       
-                                       /* Set it to here to encourage the allocator to 
-                                        *  go forth from here.
-                                        */
                                         
-                                       /* Yaffs2 sanity check:
-                                        * This should be the one with the highest sequence number
-                                        */
-                                       if (dev->isYaffs2
-                                           && (dev->sequenceNumber !=
-                                               bi->sequenceNumber)) {
-                                               T(YAFFS_TRACE_ALWAYS,
-                                                 (TSTR
-                                                  ("yaffs: Allocation block %d was not highest sequence "
-                                                   "id: block seq = %d, dev seq = %d"
-                                                   TENDSTR), blk,
-                                                  bi->sequenceNumber,
-                                                  dev->sequenceNumber));
-                                       }
                                }
 
                                dev->nFreeChunks++;
+                               
                        } else if (tags.chunkId > 0) {
                                /* chunkId > 0 so it is a data chunk... */
                                unsigned int endpos;
-
                                __u32 chunkBase =
-                                   (tags.chunkId - 1) * dev->nBytesPerChunk;
+                                   (tags.chunkId - 1) * dev->nDataBytesPerChunk;
+                                                               
+                               foundChunksInBlock = 1;
+
 
                                yaffs_SetChunkBit(dev, blk, c);
                                bi->pagesInUse++;
@@ -4693,19 +6192,27 @@ static int yaffs_ScanBackwards(yaffs_Device * dev)
                                                                      tags.
                                                                      objectId,
                                                                      YAFFS_OBJECT_TYPE_FILE);
-                               if (in->variantType == YAFFS_OBJECT_TYPE_FILE
+                               if(!in){
+                                       /* Out of memory */
+                                       alloc_failed = 1;
+                               }
+                               
+                               if (in &&
+                                   in->variantType == YAFFS_OBJECT_TYPE_FILE
                                    && chunkBase <
                                    in->variant.fileVariant.shrinkSize) {
                                        /* This has not been invalidated by a resize */
-                                       yaffs_PutChunkIntoFile(in, tags.chunkId,
-                                                              chunk, -1);
+                                       if(!yaffs_PutChunkIntoFile(in, tags.chunkId,
+                                                              chunk, -1)){
+                                               alloc_failed = 1;
+                                       }
 
                                        /* File size is calculated by looking at the data chunks if we have not 
                                         * seen an object header yet. Stop this practice once we find an object header.
                                         */
                                        endpos =
                                            (tags.chunkId -
-                                            1) * dev->nBytesPerChunk +
+                                            1) * dev->nDataBytesPerChunk +
                                            tags.byteCount;
                                            
                                        if (!in->valid &&       /* have not got an object header yet */
@@ -4719,7 +6226,7 @@ static int yaffs_ScanBackwards(yaffs_Device * dev)
                                                    scannedFileSize;
                                        }
 
-                               } else {
+                               } else if(in) {
                                        /* This chunk has been invalidated by a resize, so delete */
                                        yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
 
@@ -4728,6 +6235,8 @@ static int yaffs_ScanBackwards(yaffs_Device * dev)
                                /* chunkId == 0, so it is an ObjectHeader.
                                 * Thus, we read in the object header and make the object
                                 */
+                               foundChunksInBlock = 1;
+
                                yaffs_SetChunkBit(dev, blk, c);
                                bi->pagesInUse++;
 
@@ -4755,7 +6264,7 @@ static int yaffs_ScanBackwards(yaffs_Device * dev)
                                         * living with invalid data until needed.
                                         */
 
-                                       yaffs_ReadChunkWithTagsFromNAND(dev,
+                                       result = yaffs_ReadChunkWithTagsFromNAND(dev,
                                                                        chunk,
                                                                        chunkData,
                                                                        NULL);
@@ -5005,16 +6514,21 @@ static int yaffs_ScanBackwards(yaffs_Device * dev)
                                                /* Do nothing */
                                                break;
                                        case YAFFS_OBJECT_TYPE_SYMLINK:
-                                               if(oh)
+                                               if(oh){
                                                   in->variant.symLinkVariant.alias =
                                                    yaffs_CloneString(oh->
                                                                      alias);
+                                                  if(!in->variant.symLinkVariant.alias)
+                                                       alloc_failed = 1;
+                                               }
                                                break;
                                        }
 
                                }
+                               
                        }
-               }
+
+               } /* End of scanning for each chunk */
 
                if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
                        /* If we got this far while scanning, then the block is fully allocated. */
@@ -5032,37 +6546,22 @@ static int yaffs_ScanBackwards(yaffs_Device * dev)
 
        }
 
-       if (blockIndex) {
+       if (altBlockIndex) 
+               YFREE_ALT(blockIndex);
+       else
                YFREE(blockIndex);
-       }
+       
        /* Ok, we've done all the scanning.
         * Fix up the hard link chains.
         * We should now have scanned all the objects, now it's time to add these 
         * hardlinks.
         */
-       while (hardList) {
-               hl = hardList;
-               hardList = (yaffs_Object *) (hardList->hardLinks.next);
-
-               in = yaffs_FindObjectByNumber(dev,
-                                             hl->variant.hardLinkVariant.
-                                             equivalentObjectId);
-
-               if (in) {
-                       /* Add the hardlink pointers */
-                       hl->variant.hardLinkVariant.equivalentObject = in;
-                       list_add(&hl->hardLinks, &in->hardLinks);
-               } else {
-                       /* Todo Need to report/handle this better.
-                        * Got a problem... hardlink to a non-existant object
-                        */
-                       hl->variant.hardLinkVariant.equivalentObject = NULL;
-                       INIT_LIST_HEAD(&hl->hardLinks);
-
-               }
-
-       }
-
+       yaffs_HardlinkFixup(dev,hardList);
+       
+       
+       /*
+       *  Sort out state of unlinked and deleted objects.
+       */
        {
                struct list_head *i;
                struct list_head *n;
@@ -5092,6 +6591,10 @@ static int yaffs_ScanBackwards(yaffs_Device * dev)
        }
 
        yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
+       
+       if(alloc_failed){
+               return YAFFS_FAIL;
+       }
 
        T(YAFFS_TRACE_SCAN, (TSTR("yaffs_ScanBackwards ends" TENDSTR)));
 
@@ -5199,7 +6702,7 @@ yaffs_Object *yaffs_FindObjectByName(yaffs_Object * directory,
                                 */
                                yaffs_GetObjectName(l, buffer,
                                                    YAFFS_MAX_NAME_LENGTH);
-                               if (yaffs_strcmp(name, buffer) == 0) {
+                               if (yaffs_strncmp(name, buffer,YAFFS_MAX_NAME_LENGTH) == 0) {
                                        return l;
                                }
 
@@ -5255,6 +6758,7 @@ yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object * obj)
        if (obj && obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
                /* We want the object id of the equivalent object, not this one */
                obj = obj->variant.hardLinkVariant.equivalentObject;
+               yaffs_CheckObjectDetailsLoaded(obj);
        }
        return obj;
 
@@ -5282,14 +6786,15 @@ int yaffs_GetObjectName(yaffs_Object * obj, YCHAR * name, int buffSize)
        }
 #endif
        else {
+               int result;
                __u8 *buffer = yaffs_GetTempBuffer(obj->myDev, __LINE__);
 
                yaffs_ObjectHeader *oh = (yaffs_ObjectHeader *) buffer;
 
-               memset(buffer, 0, obj->myDev->nBytesPerChunk);
+               memset(buffer, 0, obj->myDev->nDataBytesPerChunk);
 
                if (obj->chunkId >= 0) {
-                       yaffs_ReadChunkWithTagsFromNAND(obj->myDev,
+                       result = yaffs_ReadChunkWithTagsFromNAND(obj->myDev,
                                                        obj->chunkId, buffer,
                                                        NULL);
                }
@@ -5314,7 +6819,7 @@ int yaffs_GetObjectFileLength(yaffs_Object * obj)
                return yaffs_strlen(obj->variant.symLinkVariant.alias);
        } else {
                /* Only a directory should drop through to here */
-               return obj->myDev->nBytesPerChunk;
+               return obj->myDev->nDataBytesPerChunk;
        }
 }
 
@@ -5490,12 +6995,40 @@ static int yaffs_CheckDevFunctions(const yaffs_Device * dev)
        return 0;               /* bad */
 }
 
+
+static int yaffs_CreateInitialDirectories(yaffs_Device *dev)
+{
+       /* Initialise the unlinked, deleted, root and lost and found directories */
+       
+       dev->lostNFoundDir = dev->rootDir =  NULL;
+       dev->unlinkedDir = dev->deletedDir = NULL;
+
+       dev->unlinkedDir =
+           yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_UNLINKED, S_IFDIR);
+       
+       dev->deletedDir =
+           yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_DELETED, S_IFDIR);
+
+       dev->rootDir =
+           yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_ROOT,
+                                     YAFFS_ROOT_MODE | S_IFDIR);
+       dev->lostNFoundDir =
+           yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_LOSTNFOUND,
+                                     YAFFS_LOSTNFOUND_MODE | S_IFDIR);
+       
+       if(dev->lostNFoundDir && dev->rootDir && dev->unlinkedDir && dev->deletedDir){
+               yaffs_AddObjectToDirectory(dev->rootDir, dev->lostNFoundDir);
+               return YAFFS_OK;
+       }
+       
+       return YAFFS_FAIL;
+}
+
 int yaffs_GutsInitialise(yaffs_Device * dev)
 {
+       int init_failed = 0;
        unsigned x;
        int bits;
-       int extraBits;
-       int nBlocks;
 
        T(YAFFS_TRACE_TRACING, (TSTR("yaffs: yaffs_GutsInitialise()" TENDSTR)));
 
@@ -5521,12 +7054,18 @@ int yaffs_GutsInitialise(yaffs_Device * dev)
 
        /* Check geometry parameters. */
 
-       if ((dev->isYaffs2 && dev->nBytesPerChunk < 1024) || (!dev->isYaffs2 && dev->nBytesPerChunk != 512) || dev->nChunksPerBlock < 2 || dev->nReservedBlocks < 2 || dev->internalStartBlock <= 0 || dev->internalEndBlock <= 0 || dev->internalEndBlock <= (dev->internalStartBlock + dev->nReservedBlocks + 2)      // otherwise it is too small
+       if ((dev->isYaffs2 && dev->nDataBytesPerChunk < 1024) || 
+           (!dev->isYaffs2 && dev->nDataBytesPerChunk != 512) || 
+            dev->nChunksPerBlock < 2 || 
+            dev->nReservedBlocks < 2 || 
+            dev->internalStartBlock <= 0 || 
+            dev->internalEndBlock <= 0 || 
+            dev->internalEndBlock <= (dev->internalStartBlock + dev->nReservedBlocks + 2)      // otherwise it is too small
            ) {
                T(YAFFS_TRACE_ALWAYS,
                  (TSTR
                   ("yaffs: NAND geometry problems: chunk size %d, type is yaffs%s "
-                   TENDSTR), dev->nBytesPerChunk, dev->isYaffs2 ? "2" : ""));
+                   TENDSTR), dev->nDataBytesPerChunk, dev->isYaffs2 ? "2" : ""));
                return YAFFS_FAIL;
        }
 
@@ -5563,23 +7102,40 @@ int yaffs_GutsInitialise(yaffs_Device * dev)
 
        dev->isMounted = 1;
 
-       nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
 
-       /* OK now calculate a few things for the device
+
+       /* OK now calculate a few things for the device */
+       
+       /*
+        *  Calculate all the chunk size manipulation numbers: 
+        */
+        /* Start off assuming it is a power of 2 */
+        dev->chunkShift = ShiftDiv(dev->nDataBytesPerChunk);
+        dev->chunkMask = (1<<dev->chunkShift) - 1;
+
+        if(dev->nDataBytesPerChunk == (dev->chunkMask + 1)){
+               /* Yes it is a power of 2, disable crumbs */
+               dev->crumbMask = 0;
+               dev->crumbShift = 0;
+               dev->crumbsPerChunk = 0;
+        } else {
+               /* Not a power of 2, use crumbs instead */
+               dev->crumbShift = ShiftDiv(sizeof(yaffs_PackedTags2TagsPart));
+               dev->crumbMask = (1<<dev->crumbShift)-1;
+               dev->crumbsPerChunk = dev->nDataBytesPerChunk/(1 << dev->crumbShift);
+               dev->chunkShift = 0;
+               dev->chunkMask = 0;
+       }
+               
+
+       /*
         * Calculate chunkGroupBits.
         * We need to find the next power of 2 > than internalEndBlock
         */
 
        x = dev->nChunksPerBlock * (dev->internalEndBlock + 1);
-
-       for (bits = extraBits = 0; x > 1; bits++) {
-               if (x & 1)
-                       extraBits++;
-               x >>= 1;
-       }
-
-       if (extraBits > 0)
-               bits++;
+       
+       bits = ShiftsGE(x);
        
        /* Set up tnode width if wide tnodes are enabled. */
        if(!dev->wideTnodesDisabled){
@@ -5639,72 +7195,114 @@ int yaffs_GutsInitialise(yaffs_Device * dev)
        dev->nErasureFailures = 0;
        dev->nErasedBlocks = 0;
        dev->isDoingGC = 0;
+       dev->hasPendingPrioritisedGCs = 1; /* Assume the worst for now, will get fixed on first GC */
 
-       /* Initialise temporary buffers */
-       {
-               int i;
-               for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
-                       dev->tempBuffer[i].line = 0;    /* not in use */
-                       dev->tempBuffer[i].buffer =
-                           YMALLOC(dev->nBytesPerChunk);
-               }
-       }
-
-       yaffs_InitialiseBlocks(dev, nBlocks);
-
-       yaffs_InitialiseTnodes(dev);
-
-       yaffs_InitialiseObjects(dev);
-
-       dev->gcCleanupList = YMALLOC(dev->nChunksPerBlock * sizeof(__u32));
-
-       if (dev->nShortOpCaches > 0) {
+       /* Initialise temporary buffers and caches. */
+       if(!yaffs_InitialiseTempBuffers(dev))
+               init_failed = 1;
+       
+       dev->srCache = NULL;
+       dev->gcCleanupList = NULL;
+       
+       
+       if (!init_failed &&
+           dev->nShortOpCaches > 0) {
                int i;
+               __u8 *buf;
+               int srCacheBytes = dev->nShortOpCaches * sizeof(yaffs_ChunkCache);
 
                if (dev->nShortOpCaches > YAFFS_MAX_SHORT_OP_CACHES) {
                        dev->nShortOpCaches = YAFFS_MAX_SHORT_OP_CACHES;
                }
 
-               dev->srCache =
-                   YMALLOC(dev->nShortOpCaches * sizeof(yaffs_ChunkCache));
-
-               for (i = 0; i < dev->nShortOpCaches; i++) {
+               buf = dev->srCache =  YMALLOC(srCacheBytes);
+                   
+               if(dev->srCache)
+                       memset(dev->srCache,0,srCacheBytes);
+                  
+               for (i = 0; i < dev->nShortOpCaches && buf; i++) {
                        dev->srCache[i].object = NULL;
                        dev->srCache[i].lastUse = 0;
                        dev->srCache[i].dirty = 0;
-                       dev->srCache[i].data = YMALLOC(dev->nBytesPerChunk);
+                       dev->srCache[i].data = buf = YMALLOC_DMA(dev->nDataBytesPerChunk);
                }
+               if(!buf)
+                       init_failed = 1;
+                       
                dev->srLastUse = 0;
        }
 
        dev->cacheHits = 0;
+       
+       if(!init_failed){
+               dev->gcCleanupList = YMALLOC(dev->nChunksPerBlock * sizeof(__u32));
+               if(!dev->gcCleanupList)
+                       init_failed = 1;
+       }
 
-       /* Initialise the unlinked, root and lost and found directories */
-       dev->lostNFoundDir = dev->rootDir =  NULL;
-       dev->unlinkedDir = dev->deletedDir = NULL;
+       if (dev->isYaffs2) {
+               dev->useHeaderFileSize = 1;
+       }
+       if(!init_failed && !yaffs_InitialiseBlocks(dev))
+               init_failed = 1;
+               
+       yaffs_InitialiseTnodes(dev);
+       yaffs_InitialiseObjects(dev);
 
-       dev->unlinkedDir =
-           yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_UNLINKED, S_IFDIR);
-       dev->deletedDir =
-           yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_DELETED, S_IFDIR);
+       if(!init_failed && !yaffs_CreateInitialDirectories(dev))
+               init_failed = 1;
 
-       dev->rootDir =
-           yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_ROOT,
-                                     YAFFS_ROOT_MODE | S_IFDIR);
-       dev->lostNFoundDir =
-           yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_LOSTNFOUND,
-                                     YAFFS_LOSTNFOUND_MODE | S_IFDIR);
-       yaffs_AddObjectToDirectory(dev->rootDir, dev->lostNFoundDir);
 
-       if (dev->isYaffs2) {
-               dev->useHeaderFileSize = 1;
+       if(!init_failed){
+               /* Now scan the flash. */
+               if (dev->isYaffs2) {
+                       if(yaffs_CheckpointRestore(dev)) {
+                               T(YAFFS_TRACE_ALWAYS,
+                                 (TSTR("yaffs: restored from checkpoint" TENDSTR)));
+                       } else {
+
+                               /* Clean up the mess caused by an aborted checkpoint load 
+                                * and scan backwards. 
+                                */
+                               yaffs_DeinitialiseBlocks(dev);
+                               yaffs_DeinitialiseTnodes(dev);
+                               yaffs_DeinitialiseObjects(dev);
+                               
+                       
+                               dev->nErasedBlocks = 0;
+                               dev->nFreeChunks = 0;
+                               dev->allocationBlock = -1;
+                               dev->allocationPage = -1;
+                               dev->nDeletedFiles = 0;
+                               dev->nUnlinkedFiles = 0;
+                               dev->nBackgroundDeletions = 0;
+                               dev->oldestDirtySequence = 0;
+
+                               if(!init_failed && !yaffs_InitialiseBlocks(dev))
+                                       init_failed = 1;
+                                       
+                               yaffs_InitialiseTnodes(dev);
+                               yaffs_InitialiseObjects(dev);
+
+                               if(!init_failed && !yaffs_CreateInitialDirectories(dev))
+                                       init_failed = 1;
+
+                               if(!init_failed && !yaffs_ScanBackwards(dev))
+                                       init_failed = 1;
+                       }
+               }else
+                       if(!yaffs_Scan(dev))
+                               init_failed = 1;
        }
+               
+       if(init_failed){
+               /* Clean up the mess */
+               T(YAFFS_TRACE_TRACING,
+                 (TSTR("yaffs: yaffs_GutsInitialise() aborted.\n" TENDSTR)));
 
-       /* Now scan the flash.   */
-       if (dev->isYaffs2)
-               yaffs_ScanBackwards(dev);
-       else
-               yaffs_Scan(dev);
+               yaffs_Deinitialise(dev);
+               return YAFFS_FAIL;
+       }
 
        /* Zero out stats */
        dev->nPageReads = 0;
@@ -5716,6 +7314,8 @@ int yaffs_GutsInitialise(yaffs_Device * dev)
        dev->nRetiredBlocks = 0;
 
        yaffs_VerifyFreeChunks(dev);
+       yaffs_VerifyBlocks(dev);
+       
 
        T(YAFFS_TRACE_TRACING,
          (TSTR("yaffs: yaffs_GutsInitialise() done.\n" TENDSTR)));
@@ -5731,13 +7331,17 @@ void yaffs_Deinitialise(yaffs_Device * dev)
                yaffs_DeinitialiseBlocks(dev);
                yaffs_DeinitialiseTnodes(dev);
                yaffs_DeinitialiseObjects(dev);
-               if (dev->nShortOpCaches > 0) {
+               if (dev->nShortOpCaches > 0 &&
+                   dev->srCache) {
 
                        for (i = 0; i < dev->nShortOpCaches; i++) {
-                               YFREE(dev->srCache[i].data);
+                               if(dev->srCache[i].data)
+                                       YFREE(dev->srCache[i].data);
+                               dev->srCache[i].data = NULL;
                        }
 
                        YFREE(dev->srCache);
+                       dev->srCache = NULL;
                }
 
                YFREE(dev->gcCleanupList);
@@ -5786,6 +7390,7 @@ int yaffs_GetNumberOfFreeChunks(yaffs_Device * dev)
 
        int nFree;
        int nDirtyCacheChunks;
+       int blocksForCheckpoint;
 
 #if 1
        nFree = dev->nFreeChunks;
@@ -5808,6 +7413,13 @@ int yaffs_GetNumberOfFreeChunks(yaffs_Device * dev)
        nFree -= nDirtyCacheChunks;
 
        nFree -= ((dev->nReservedBlocks + 1) * dev->nChunksPerBlock);
+       
+       /* Now we figure out how much to reserve for the checkpoint and report that... */
+       blocksForCheckpoint = dev->nCheckpointReservedBlocks - dev->blocksInCheckpoint;
+       if(blocksForCheckpoint < 0)
+               blocksForCheckpoint = 0;
+               
+       nFree -= (blocksForCheckpoint * dev->nChunksPerBlock);
 
        if (nFree < 0)
                nFree = 0;
@@ -5820,9 +7432,15 @@ static int yaffs_freeVerificationFailures;
 
 static void yaffs_VerifyFreeChunks(yaffs_Device * dev)
 {
-       int counted = yaffs_CountFreeChunks(dev);
+       int counted;
+       int difference;
+       
+       if(yaffs_SkipVerification(dev))
+               return;
+       
+       counted = yaffs_CountFreeChunks(dev);
 
-       int difference = dev->nFreeChunks - counted;
+       difference = dev->nFreeChunks - counted;
 
        if (difference) {
                T(YAFFS_TRACE_ALWAYS,