yaffs_tagscompat.c

YAFFS和YASFF2文件系统的源代码。

{
	dev->nBlockErasures++;
	return dev->eraseBlockInNAND(dev,blockInNAND);
}

int yaffs_InitialiseNAND(struct yaffs_DeviceStruct *dev)
{
	return dev->initialiseNAND(dev);
}

#endif

#if 0
static int yaffs_WriteNewChunkToNAND(struct yaffs_DeviceStruct *dev, const __u8 *data, yaffs_Spare *spare,int useReserve)
{
	int chunk;

	int writeOk = 1;
	int attempts = 0;

	unsigned char rbData[YAFFS_BYTES_PER_CHUNK];
	yaffs_Spare rbSpare;

	do{
		chunk = yaffs_AllocateChunk(dev,useReserve);

		if(chunk >= 0)
		{

			// First check this chunk is erased...
#ifndef CONFIG_YAFFS_DISABLE_CHUNK_ERASED_CHECK
			writeOk = yaffs_CheckChunkErased(dev,chunk);
#endif
			if(!writeOk)
			{
				T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs chunk %d was not erased" TENDSTR),chunk));
			}
			else
			{
				writeOk =  yaffs_WriteChunkToNAND(dev,chunk,data,spare);
			}
			attempts++;
			if(writeOk)
			{
				// Readback & verify
				// If verify fails, then delete this chunk and try again
				// To verify we compare everything except the block and
				// page status bytes.
				// NB We check a raw read without ECC correction applied
				yaffs_ReadChunkFromNAND(dev,chunk,rbData,&rbSpare,0);

#ifndef CONFIG_YAFFS_DISABLE_WRITE_VERIFY
				if(!yaffs_VerifyCompare(data,rbData,spare,&rbSpare))
				{
					// Didn't verify
					T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs write verify failed on chunk %d" TENDSTR), chunk));

					writeOk = 0;
				}
#endif

			}
			if(writeOk)
			{
				// Copy the data into the write buffer.
				// NB We do this at the end to prevent duplicates in the case of a write error.
				//Todo
				yaffs_HandleWriteChunkOk(dev,chunk,data,spare);
			}
			else
			{
				yaffs_HandleWriteChunkError(dev,chunk);
			}
		}

	} while(chunk >= 0 && ! writeOk);

	if(attempts > 1)
	{
		T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs write required %d attempts" TENDSTR),attempts));
		dev->nRetriedWrites+= (attempts - 1);
	}

	return chunk;
}

#endif

///
// Functions for robustisizing
//
//
#if 0

static void yaffs_RetireBlock(yaffs_Device *dev,int blockInNAND)
{
	// Ding the blockStatus in the first two pages of the block.

	yaffs_Spare spare;

	memset(&spare, 0xff,sizeof(yaffs_Spare));

	spare.blockStatus = 0;

	// TODO change this retirement marking for other NAND types
	yaffs_WriteChunkToNAND(dev, blockInNAND * dev->nChunksPerBlock, NULL , &spare);
	yaffs_WriteChunkToNAND(dev, blockInNAND * dev->nChunksPerBlock + 1, NULL , &spare);

	yaffs_GetBlockInfo(dev,blockInNAND)->blockState = YAFFS_BLOCK_STATE_DEAD;
	dev->nRetiredBlocks++;
}

#endif

#if 0
static int yaffs_RewriteBufferedBlock(yaffs_Device *dev)
{
	dev->doingBufferedBlockRewrite = 1;
	//
	//	Remove erased chunks
	//  Rewrite existing chunks to a new block
	//	Set current write block to the new block

	dev->doingBufferedBlockRewrite = 0;

	return 1;
}

#endif

static void yaffs_HandleReadDataError(yaffs_Device *dev,int chunkInNAND)
{
	int blockInNAND = chunkInNAND/dev->nChunksPerBlock;

	// Mark the block for retirement
	yaffs_GetBlockInfo(dev,blockInNAND)->needsRetiring = 1;
	T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,(TSTR("**>>Block %d marked for retirement" TENDSTR),blockInNAND));


	//TODO
	// Just do a garbage collection on the affected block then retire the block
	// NB recursion
}


static void yaffs_CheckWrittenBlock(yaffs_Device *dev,int chunkInNAND)
{
}

static void yaffs_HandleWriteChunkOk(yaffs_Device *dev,int chunkInNAND,const __u8 *data, const yaffs_Spare *spare)
{
}

static void yaffs_HandleUpdateChunk(yaffs_Device *dev,int chunkInNAND, const yaffs_Spare *spare)
{
}

static void yaffs_HandleWriteChunkError(yaffs_Device *dev,int chunkInNAND)
{
	int blockInNAND = chunkInNAND/dev->nChunksPerBlock;

	// Mark the block for retirement
	yaffs_GetBlockInfo(dev,blockInNAND)->needsRetiring = 1;
	// Delete the chunk
	yaffs_DeleteChunk(dev,chunkInNAND,1,__LINE__);
}




static int yaffs_VerifyCompare(const __u8 *d0, const __u8 * d1, const yaffs_Spare *s0, const yaffs_Spare *s1)
{


	if( memcmp(d0,d1,YAFFS_BYTES_PER_CHUNK) != 0 ||
		s0->tagByte0 != s1->tagByte0 ||
		s0->tagByte1 != s1->tagByte1 ||
		s0->tagByte2 != s1->tagByte2 ||
		s0->tagByte3 != s1->tagByte3 ||
		s0->tagByte4 != s1->tagByte4 ||
		s0->tagByte5 != s1->tagByte5 ||
		s0->tagByte6 != s1->tagByte6 ||
		s0->tagByte7 != s1->tagByte7 ||
		s0->ecc1[0]  != s1->ecc1[0]  ||
		s0->ecc1[1]  != s1->ecc1[1]  ||
		s0->ecc1[2]  != s1->ecc1[2]  ||
		s0->ecc2[0]  != s1->ecc2[0]  ||
		s0->ecc2[1]  != s1->ecc2[1]  ||
		s0->ecc2[2]  != s1->ecc2[2] )
		{
			return 0;
		}

	return 1;
}

#if 0
typedef struct
{

	unsigned validMarker0;
	unsigned chunkUsed;		    //  Status of the chunk: used or unused
	unsigned objectId;			// If 0 then this is not part of an object (unused)
	unsigned chunkId;			// If 0 then this is a header
	unsigned byteCount;		    // Only valid for data chunks
	// The following stuff only has meaning when we read
	yaffs_ECCResult eccResult;  // Only valid when we read.
	unsigned blockBad;			// Only valid on reading

	// YAFFS 1 stuff	
	unsigned chunkDeleted;		// The chunk is marked deleted
	unsigned serialNumber; 		// Yaffs1 2-bit serial number
	
	// YAFFS2 stuff
	unsigned sequenceNumber; 	// The sequence number of this block

	unsigned validMarker1;

} yaffs_ExtendedTags;


typedef struct
{   
    unsigned chunkId:20;
    unsigned serialNumber:2;
    unsigned byteCount:10;
    unsigned objectId:18;
    unsigned ecc:12;
    unsigned unusedStuff:2;
} yaffs_Tags;


#endif

int yaffs_TagsCompatabilityWriteChunkWithTagsToNAND(yaffs_Device *dev,int chunkInNAND,const __u8 *data, const yaffs_ExtendedTags *eTags)
{
	yaffs_Spare spare;
	yaffs_Tags tags;	
	
	yaffs_SpareInitialise(&spare);
	
	if(eTags->chunkDeleted)
	{
		spare.pageStatus = 0;
	}
	else
	{
		tags.objectId = eTags->objectId;
		tags.chunkId = eTags->chunkId;
		tags.byteCount = eTags->byteCount;
		tags.serialNumber = eTags->serialNumber;
		
		 yaffs_LoadTagsIntoSpare(&spare,&tags);
		
	}
	
	return yaffs_WriteChunkToNAND(dev,chunkInNAND,data,&spare);
}


int yaffs_TagsCompatabilityReadChunkWithTagsFromNAND(yaffs_Device *dev,int chunkInNAND, __u8 *data, yaffs_ExtendedTags *eTags)
{

	yaffs_Spare spare;
	yaffs_Tags tags;
	yaffs_ECCResult eccResult;
	
	if(yaffs_ReadChunkFromNAND(dev,chunkInNAND,data,&spare,&eccResult,1))
	{
		 int deleted = (yaffs_CountBits(spare.pageStatus) < 7) ? 1 : 0;
			
		 yaffs_GetTagsFromSpare(dev,&spare,&tags);
		 
		 eTags->chunkDeleted = deleted;
		 eTags->objectId = tags.objectId;
		 eTags->chunkId = tags.chunkId;
		 eTags->byteCount = tags.byteCount;
		 eTags->serialNumber = tags.serialNumber;
		 eTags->eccResult = eccResult;
		 eTags->blockBad = 0; // We're reading it therefore it is not a bad block
		 
		 return YAFFS_OK;
	}
	else
	{ 
		return YAFFS_FAIL;
	}
}

int yaffs_TagsCompatabilityMarkNANDBlockBad(struct yaffs_DeviceStruct *dev, int blockInNAND)
{

	yaffs_Spare spare;

	memset(&spare, 0xff,sizeof(yaffs_Spare));

	spare.blockStatus = 0;

	yaffs_WriteChunkToNAND(dev, blockInNAND * dev->nChunksPerBlock, NULL , &spare);
	yaffs_WriteChunkToNAND(dev, blockInNAND * dev->nChunksPerBlock + 1, NULL , &spare);
	
	return YAFFS_OK;
	
}


int yaffs_TagsCompatabilityQueryNANDBlock(struct yaffs_DeviceStruct *dev, int blockNo, yaffs_BlockState *state, int *sequenceNumber)
{
     
     yaffs_Spare spare0,spare1;
     static yaffs_Spare spareFF;
     static int init;
     yaffs_ECCResult dummy;
     
     if(!init)
     {
	     memset(&spareFF,0xFF,sizeof(spareFF));
	     init = 1;
     }
     
     *sequenceNumber = 0;
     
     yaffs_ReadChunkFromNAND(dev,blockNo * dev->nChunksPerBlock,NULL,&spare0,&dummy,1);
     yaffs_ReadChunkFromNAND(dev,blockNo * dev->nChunksPerBlock + 1,NULL,&spare1,&dummy,1);
     
     if(yaffs_CountBits(spare0.blockStatus & spare1.blockStatus) < 7)
     	*state = YAFFS_BLOCK_STATE_DEAD;
     else if(memcmp(&spareFF,&spare0,sizeof(spareFF)) == 0)
         *state = YAFFS_BLOCK_STATE_EMPTY;
     else
	 *state = YAFFS_BLOCK_STATE_NEEDS_SCANNING;  

     return YAFFS_OK;
}