yaffs_guts.c

yaffs2 source code for linux

	int blockInNAND = chunkInNAND / dev->nChunksPerBlock;
	yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockInNAND);

	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__);
}


/*---------------- Name handling functions ------------*/ 

static __u16 yaffs_CalcNameSum(const YCHAR * name)
{
	__u16 sum = 0;
	__u16 i = 1;

	const YUCHAR *bname = (const YUCHAR *) name;
	if (bname) {
		while ((*bname) && (i < (YAFFS_MAX_NAME_LENGTH/2))) {

#ifdef CONFIG_YAFFS_CASE_INSENSITIVE
			sum += yaffs_toupper(*bname) * i;
#else
			sum += (*bname) * i;
#endif
			i++;
			bname++;
		}
	}
	
	return sum;
}

static void yaffs_SetObjectName(yaffs_Object * obj, const YCHAR * name)
{
#ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
	memset(obj->shortName,0,sizeof (YCHAR) * (YAFFS_SHORT_NAME_LENGTH+1)); 
	if (name && yaffs_strlen(name) <= YAFFS_SHORT_NAME_LENGTH) {
		yaffs_strcpy(obj->shortName, name);
	} else {
		obj->shortName[0] = _Y('\0');
	}
#endif
	obj->sum = yaffs_CalcNameSum(name);
}

/*-------------------- TNODES -------------------

 * List of spare tnodes
 * The list is hooked together using the first pointer
 * in the tnode.
 */
 
/* yaffs_CreateTnodes creates a bunch more tnodes and
 * adds them to the tnode free list.
 * Don't use this function directly
 */

static int yaffs_CreateTnodes(yaffs_Device * dev, int nTnodes)
{
	int i;
	int tnodeSize;
	yaffs_Tnode *newTnodes;
	__u8 *mem;
	yaffs_Tnode *curr;
	yaffs_Tnode *next;
	yaffs_TnodeList *tnl;

	if (nTnodes < 1)
		return YAFFS_OK;
		
	/* Calculate the tnode size in bytes for variable width tnode support.
	 * Must be a multiple of 32-bits  */
	tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;

	if(tnodeSize < sizeof(yaffs_Tnode))
		tnodeSize = sizeof(yaffs_Tnode);
		

	/* make these things */

	newTnodes = YMALLOC(nTnodes * tnodeSize);
	mem = (__u8 *)newTnodes;

	if (!newTnodes) {
		T(YAFFS_TRACE_ERROR,
		  (TSTR("yaffs: Could not allocate Tnodes" TENDSTR)));
		return YAFFS_FAIL;
	}

	/* Hook them into the free list */
#if 0
	for (i = 0; i < nTnodes - 1; i++) {
		newTnodes[i].internal[0] = &newTnodes[i + 1];
#ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
		newTnodes[i].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
#endif
	}

	newTnodes[nTnodes - 1].internal[0] = dev->freeTnodes;
#ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
	newTnodes[nTnodes - 1].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
#endif
	dev->freeTnodes = newTnodes;
#else
	/* New hookup for wide tnodes */
	for(i = 0; i < nTnodes -1; i++) {
		curr = (yaffs_Tnode *) &mem[i * tnodeSize];
		next = (yaffs_Tnode *) &mem[(i+1) * tnodeSize];
		curr->internal[0] = next;
	}
	
	curr = (yaffs_Tnode *) &mem[(nTnodes - 1) * tnodeSize];
	curr->internal[0] = dev->freeTnodes;
	dev->freeTnodes = (yaffs_Tnode *)mem;

#endif


	dev->nFreeTnodes += nTnodes;
	dev->nTnodesCreated += nTnodes;

	/* Now add this bunch of tnodes to a list for freeing up.
	 * NB If we can't add this to the management list it isn't fatal
	 * but it just means we can't free this bunch of tnodes later.
	 */
	 
	tnl = YMALLOC(sizeof(yaffs_TnodeList));
	if (!tnl) {
		T(YAFFS_TRACE_ERROR,
		  (TSTR
		   ("yaffs: Could not add tnodes to management list" TENDSTR)));
		   return YAFFS_FAIL;

	} else {
		tnl->tnodes = newTnodes;
		tnl->next = dev->allocatedTnodeList;
		dev->allocatedTnodeList = tnl;
	}

	T(YAFFS_TRACE_ALLOCATE, (TSTR("yaffs: Tnodes added" TENDSTR)));

	return YAFFS_OK;
}

/* GetTnode gets us a clean tnode. Tries to make allocate more if we run out */

static yaffs_Tnode *yaffs_GetTnodeRaw(yaffs_Device * dev)
{
	yaffs_Tnode *tn = NULL;

	/* If there are none left make more */
	if (!dev->freeTnodes) {
		yaffs_CreateTnodes(dev, YAFFS_ALLOCATION_NTNODES);
	}

	if (dev->freeTnodes) {
		tn = dev->freeTnodes;
#ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
		if (tn->internal[YAFFS_NTNODES_INTERNAL] != (void *)1) {
			/* Hoosterman, this thing looks like it isn't in the list */
			T(YAFFS_TRACE_ALWAYS,
			  (TSTR("yaffs: Tnode list bug 1" TENDSTR)));
		}
#endif
		dev->freeTnodes = dev->freeTnodes->internal[0];
		dev->nFreeTnodes--;
	}

	dev->nCheckpointBlocksRequired = 0; /* force recalculation*/

	return tn;
}

static yaffs_Tnode *yaffs_GetTnode(yaffs_Device * dev)
{
	yaffs_Tnode *tn = yaffs_GetTnodeRaw(dev);
	int tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;

	if(tnodeSize < sizeof(yaffs_Tnode))
		tnodeSize = sizeof(yaffs_Tnode);
	
	if(tn)
		memset(tn, 0, tnodeSize);

	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)
{
	if (tn) {
#ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
		if (tn->internal[YAFFS_NTNODES_INTERNAL] != 0) {
			/* Hoosterman, this thing looks like it is already in the list */
			T(YAFFS_TRACE_ALWAYS,
			  (TSTR("yaffs: Tnode list bug 2" TENDSTR)));
		}
		tn->internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
#endif
		tn->internal[0] = dev->freeTnodes;
		dev->freeTnodes = tn;
		dev->nFreeTnodes++;
	}
	dev->nCheckpointBlocksRequired = 0; /* force recalculation*/
	
}

static void yaffs_DeinitialiseTnodes(yaffs_Device * dev)
{
	/* Free the list of allocated tnodes */
	yaffs_TnodeList *tmp;

	while (dev->allocatedTnodeList) {
		tmp = dev->allocatedTnodeList->next;

		YFREE(dev->allocatedTnodeList->tnodes);
		YFREE(dev->allocatedTnodeList);
		dev->allocatedTnodeList = tmp;

	}

	dev->freeTnodes = NULL;
	dev->nFreeTnodes = 0;
}

static void yaffs_InitialiseTnodes(yaffs_Device * dev)
{
	dev->allocatedTnodeList = NULL;
	dev->freeTnodes = NULL;
	dev->nFreeTnodes = 0;
	dev->nTnodesCreated = 0;

}


void yaffs_PutLevel0Tnode(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos, unsigned val)
{
  __u32 *map = (__u32 *)tn;
  __u32 bitInMap;
  __u32 bitInWord;
  __u32 wordInMap;
  __u32 mask;
  
  pos &= YAFFS_TNODES_LEVEL0_MASK;
  val >>= dev->chunkGroupBits;
  
  bitInMap = pos * dev->tnodeWidth;
  wordInMap = bitInMap /32;
  bitInWord = bitInMap & (32 -1);
  
  mask = dev->tnodeMask << bitInWord;
  
  map[wordInMap] &= ~mask;
  map[wordInMap] |= (mask & (val << bitInWord));
  
  if(dev->tnodeWidth > (32-bitInWord)) {
    bitInWord = (32 - bitInWord);
    wordInMap++;;
    mask = dev->tnodeMask >> (/*dev->tnodeWidth -*/ bitInWord);
    map[wordInMap] &= ~mask;
    map[wordInMap] |= (mask & (val >> bitInWord));
  }
}

static __u32 yaffs_GetChunkGroupBase(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos)
{
  __u32 *map = (__u32 *)tn;
  __u32 bitInMap;
  __u32 bitInWord;
  __u32 wordInMap;
  __u32 val;
  
  pos &= YAFFS_TNODES_LEVEL0_MASK;
  
  bitInMap = pos * dev->tnodeWidth;
  wordInMap = bitInMap /32;
  bitInWord = bitInMap & (32 -1);
  
  val = map[wordInMap] >> bitInWord;
  
  if(dev->tnodeWidth > (32-bitInWord)) {
    bitInWord = (32 - bitInWord);
    wordInMap++;;
    val |= (map[wordInMap] << bitInWord);
  }
  
  val &= dev->tnodeMask;
  val <<= dev->chunkGroupBits;
  
  return val;
}

/* ------------------- End of individual tnode manipulation -----------------*/

/* ---------Functions to manipulate the look-up tree (made up of tnodes) ------
 * The look up tree is represented by the top tnode and the number of topLevel
 * in the tree. 0 means only the level 0 tnode is in the tree.
 */

/* FindLevel0Tnode finds the level 0 tnode, if one exists. */
static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device * dev,
					  yaffs_FileStructure * fStruct,
					  __u32 chunkId)
{

	yaffs_Tnode *tn = fStruct->top;
	__u32 i;
	int requiredTallness;
	int level = fStruct->topLevel;

	/* Check sane level and chunk Id */
	if (level < 0 || level > YAFFS_TNODES_MAX_LEVEL) {
		return NULL;
	}

	if (chunkId > YAFFS_MAX_CHUNK_ID) {
		return NULL;
	}

	/* First check we're tall enough (ie enough topLevel) */

	i = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
	requiredTallness = 0;
	while (i) {
		i >>= YAFFS_TNODES_INTERNAL_BITS;
		requiredTallness++;
	}

	if (requiredTallness > fStruct->topLevel) {
		/* Not tall enough, so we can't find it, return NULL. */
		return NULL;
	}

	/* Traverse down to level 0 */
	while (level > 0 && tn) {
		tn = tn->
		    internal[(chunkId >>
			       ( YAFFS_TNODES_LEVEL0_BITS + 
			         (level - 1) *
			         YAFFS_TNODES_INTERNAL_BITS)
			      ) &
			     YAFFS_TNODES_INTERNAL_MASK];
		level--;

	}

	return tn;
}

/* AddOrFindLevel0Tnode finds the level 0 tnode if it exists, otherwise first expands the tree.
 * This happens in two steps:
 *  1. If the tree isn't tall enough, then make it taller.
 *  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,
					       yaffs_Tnode *passedTn)
{

	int requiredTallness;
	int i;
	int l;
	yaffs_Tnode *tn;

	__u32 x;


	/* Check sane level and page Id */
	if (fStruct->topLevel < 0 || fStruct->topLevel > YAFFS_TNODES_MAX_LEVEL) {
		return NULL;
	}

	if (chunkId > YAFFS_MAX_CHUNK_ID) {
		return NULL;
	}

	/* First check we're tall enough (ie enough topLevel) */

	x = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
	requiredTallness = 0;
	while (x) {
		x >>= YAFFS_TNODES_INTERNAL_BITS;
		requiredTallness++;
	}


	if (requiredTallness > fStruct->topLevel) {
		/* Not tall enough,gotta make the tree taller */
		for (i = fStruct->topLevel; i < requiredTallness; i++) {
		
			tn = yaffs_GetTnode(dev);

			if (tn) {
				tn->internal[0] = fStruct->top;
				fStruct->top = tn;
			} else {
				T(YAFFS_TRACE_ERROR,
				  (TSTR("yaffs: no more tnodes" TENDSTR)));
			}
		}

		fStruct->topLevel = requiredTallness;
	}

	/* Traverse down to level 0, adding anything we need */

	l = fStruct->topLevel;
	tn = fStruct->top;
	
	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;
}

static int yaffs_FindChunkInGroup(yaffs_Device * dev, int theChunk,
				  yaffs_ExtendedTags * tags, int objectId,
				  int chunkInInode)
{
	int j;

	for (j = 0; theChunk && j < dev->chunkGroupSize; j++) {
		if (yaffs_CheckChunkBit
		    (dev, theChunk / dev->nChunksPerBlock,
		     theChunk % dev->nChunksPerBlock)) {
			yaffs_ReadChunkWithTagsFromNAND(dev, theChunk, NULL,
							tags);
			if (yaffs_TagsMatch(tags, objectId, chunkInInode)) {
				/* found it; */
				return theChunk;

			}
		}
		theChunk++;
	}
	return -1;
}


/* DeleteWorker scans backwards through the tnode tree and deletes all the
 * chunks and tnodes in the file
 * Returns 1 if the tree was deleted. 
 * Returns 0 if it stopped early due to hitting the limit and the delete is incomplete.
 */

static int yaffs_DeleteWorker(yaffs_Object * in, yaffs_Tnode * tn, __u32 level,
			      int chunkOffset, int *limit)
{
	int i;
	int chunkInInode;
	int theChunk;
	yaffs_ExtendedTags tags;
	int foundChunk;
	yaffs_Device *dev = in->myDev;

	int allDone = 1;

	if (tn) {
		if (level > 0) {

			for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
			     i--) {
				if (tn->internal[i]) {
					if (limit && (*limit) < 0) {
						allDone = 0;
					} else {
						allDone =
						    yaffs_DeleteWorker(in,
								       tn->
								       internal
								       [i],
								       level -
								       1,
								       (chunkOffset
									<<
									YAFFS_TNODES_INTERNAL_BITS)
								       + i,
								       limit);
					}
					if (allDone) {
						yaffs_FreeTnode(dev,
								tn->
								internal[i]);