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openwrt-xburst/target/linux/generic/files/fs/yaffs2/yaffs_checkptrw.c
nbd c5552ad039 rename target/linux/generic-2.6 to generic
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@21952 3c298f89-4303-0410-b956-a3cf2f4a3e73
2010-06-26 20:42:58 +00:00

405 lines
10 KiB
C

/*
* YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
*
* Copyright (C) 2002-2007 Aleph One Ltd.
* for Toby Churchill Ltd and Brightstar Engineering
*
* Created by Charles Manning <charles@aleph1.co.uk>
*
* 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_checkptrw_c_version =
"$Id: yaffs_checkptrw.c,v 1.14 2007-05-15 20:07:40 charles Exp $";
#include "yaffs_checkptrw.h"
static int yaffs_CheckpointSpaceOk(yaffs_Device *dev)
{
int blocksAvailable = dev->nErasedBlocks - dev->nReservedBlocks;
T(YAFFS_TRACE_CHECKPOINT,
(TSTR("checkpt blocks available = %d" TENDSTR),
blocksAvailable));
return (blocksAvailable <= 0) ? 0 : 1;
}
static int yaffs_CheckpointErase(yaffs_Device *dev)
{
int i;
if(!dev->eraseBlockInNAND)
return 0;
T(YAFFS_TRACE_CHECKPOINT,(TSTR("checking blocks %d to %d"TENDSTR),
dev->internalStartBlock,dev->internalEndBlock));
for(i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,i);
if(bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT){
T(YAFFS_TRACE_CHECKPOINT,(TSTR("erasing checkpt block %d"TENDSTR),i));
if(dev->eraseBlockInNAND(dev,i- dev->blockOffset /* realign */)){
bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
dev->nErasedBlocks++;
dev->nFreeChunks += dev->nChunksPerBlock;
}
else {
dev->markNANDBlockBad(dev,i);
bi->blockState = YAFFS_BLOCK_STATE_DEAD;
}
}
}
dev->blocksInCheckpoint = 0;
return 1;
}
static void yaffs_CheckpointFindNextErasedBlock(yaffs_Device *dev)
{
int i;
int blocksAvailable = dev->nErasedBlocks - dev->nReservedBlocks;
T(YAFFS_TRACE_CHECKPOINT,
(TSTR("allocating checkpt block: erased %d reserved %d avail %d next %d "TENDSTR),
dev->nErasedBlocks,dev->nReservedBlocks,blocksAvailable,dev->checkpointNextBlock));
if(dev->checkpointNextBlock >= 0 &&
dev->checkpointNextBlock <= dev->internalEndBlock &&
blocksAvailable > 0){
for(i = dev->checkpointNextBlock; i <= dev->internalEndBlock; i++){
yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,i);
if(bi->blockState == YAFFS_BLOCK_STATE_EMPTY){
dev->checkpointNextBlock = i + 1;
dev->checkpointCurrentBlock = i;
T(YAFFS_TRACE_CHECKPOINT,(TSTR("allocating checkpt block %d"TENDSTR),i));
return;
}
}
}
T(YAFFS_TRACE_CHECKPOINT,(TSTR("out of checkpt blocks"TENDSTR)));
dev->checkpointNextBlock = -1;
dev->checkpointCurrentBlock = -1;
}
static void yaffs_CheckpointFindNextCheckpointBlock(yaffs_Device *dev)
{
int i;
yaffs_ExtendedTags tags;
T(YAFFS_TRACE_CHECKPOINT,(TSTR("find next checkpt block: start: blocks %d next %d" TENDSTR),
dev->blocksInCheckpoint, dev->checkpointNextBlock));
if(dev->blocksInCheckpoint < dev->checkpointMaxBlocks)
for(i = dev->checkpointNextBlock; i <= dev->internalEndBlock; i++){
int chunk = i * dev->nChunksPerBlock;
int realignedChunk = chunk - dev->chunkOffset;
dev->readChunkWithTagsFromNAND(dev,realignedChunk,NULL,&tags);
T(YAFFS_TRACE_CHECKPOINT,(TSTR("find next checkpt block: search: block %d oid %d seq %d eccr %d" TENDSTR),
i, tags.objectId,tags.sequenceNumber,tags.eccResult));
if(tags.sequenceNumber == YAFFS_SEQUENCE_CHECKPOINT_DATA){
/* Right kind of block */
dev->checkpointNextBlock = tags.objectId;
dev->checkpointCurrentBlock = i;
dev->checkpointBlockList[dev->blocksInCheckpoint] = i;
dev->blocksInCheckpoint++;
T(YAFFS_TRACE_CHECKPOINT,(TSTR("found checkpt block %d"TENDSTR),i));
return;
}
}
T(YAFFS_TRACE_CHECKPOINT,(TSTR("found no more checkpt blocks"TENDSTR)));
dev->checkpointNextBlock = -1;
dev->checkpointCurrentBlock = -1;
}
int yaffs_CheckpointOpen(yaffs_Device *dev, int forWriting)
{
/* Got the functions we need? */
if (!dev->writeChunkWithTagsToNAND ||
!dev->readChunkWithTagsFromNAND ||
!dev->eraseBlockInNAND ||
!dev->markNANDBlockBad)
return 0;
if(forWriting && !yaffs_CheckpointSpaceOk(dev))
return 0;
if(!dev->checkpointBuffer)
dev->checkpointBuffer = YMALLOC_DMA(dev->nDataBytesPerChunk);
if(!dev->checkpointBuffer)
return 0;
dev->checkpointPageSequence = 0;
dev->checkpointOpenForWrite = forWriting;
dev->checkpointByteCount = 0;
dev->checkpointSum = 0;
dev->checkpointXor = 0;
dev->checkpointCurrentBlock = -1;
dev->checkpointCurrentChunk = -1;
dev->checkpointNextBlock = dev->internalStartBlock;
/* Erase all the blocks in the checkpoint area */
if(forWriting){
memset(dev->checkpointBuffer,0,dev->nDataBytesPerChunk);
dev->checkpointByteOffset = 0;
return yaffs_CheckpointErase(dev);
} else {
int i;
/* Set to a value that will kick off a read */
dev->checkpointByteOffset = dev->nDataBytesPerChunk;
/* A checkpoint block list of 1 checkpoint block per 16 block is (hopefully)
* going to be way more than we need */
dev->blocksInCheckpoint = 0;
dev->checkpointMaxBlocks = (dev->internalEndBlock - dev->internalStartBlock)/16 + 2;
dev->checkpointBlockList = YMALLOC(sizeof(int) * dev->checkpointMaxBlocks);
for(i = 0; i < dev->checkpointMaxBlocks; i++)
dev->checkpointBlockList[i] = -1;
}
return 1;
}
int yaffs_GetCheckpointSum(yaffs_Device *dev, __u32 *sum)
{
__u32 compositeSum;
compositeSum = (dev->checkpointSum << 8) | (dev->checkpointXor & 0xFF);
*sum = compositeSum;
return 1;
}
static int yaffs_CheckpointFlushBuffer(yaffs_Device *dev)
{
int chunk;
int realignedChunk;
yaffs_ExtendedTags tags;
if(dev->checkpointCurrentBlock < 0){
yaffs_CheckpointFindNextErasedBlock(dev);
dev->checkpointCurrentChunk = 0;
}
if(dev->checkpointCurrentBlock < 0)
return 0;
tags.chunkDeleted = 0;
tags.objectId = dev->checkpointNextBlock; /* Hint to next place to look */
tags.chunkId = dev->checkpointPageSequence + 1;
tags.sequenceNumber = YAFFS_SEQUENCE_CHECKPOINT_DATA;
tags.byteCount = dev->nDataBytesPerChunk;
if(dev->checkpointCurrentChunk == 0){
/* First chunk we write for the block? Set block state to
checkpoint */
yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,dev->checkpointCurrentBlock);
bi->blockState = YAFFS_BLOCK_STATE_CHECKPOINT;
dev->blocksInCheckpoint++;
}
chunk = dev->checkpointCurrentBlock * dev->nChunksPerBlock + dev->checkpointCurrentChunk;
T(YAFFS_TRACE_CHECKPOINT,(TSTR("checkpoint wite buffer nand %d(%d:%d) objid %d chId %d" TENDSTR),
chunk, dev->checkpointCurrentBlock, dev->checkpointCurrentChunk,tags.objectId,tags.chunkId));
realignedChunk = chunk - dev->chunkOffset;
dev->writeChunkWithTagsToNAND(dev,realignedChunk,dev->checkpointBuffer,&tags);
dev->checkpointByteOffset = 0;
dev->checkpointPageSequence++;
dev->checkpointCurrentChunk++;
if(dev->checkpointCurrentChunk >= dev->nChunksPerBlock){
dev->checkpointCurrentChunk = 0;
dev->checkpointCurrentBlock = -1;
}
memset(dev->checkpointBuffer,0,dev->nDataBytesPerChunk);
return 1;
}
int yaffs_CheckpointWrite(yaffs_Device *dev,const void *data, int nBytes)
{
int i=0;
int ok = 1;
__u8 * dataBytes = (__u8 *)data;
if(!dev->checkpointBuffer)
return 0;
if(!dev->checkpointOpenForWrite)
return -1;
while(i < nBytes && ok) {
dev->checkpointBuffer[dev->checkpointByteOffset] = *dataBytes ;
dev->checkpointSum += *dataBytes;
dev->checkpointXor ^= *dataBytes;
dev->checkpointByteOffset++;
i++;
dataBytes++;
dev->checkpointByteCount++;
if(dev->checkpointByteOffset < 0 ||
dev->checkpointByteOffset >= dev->nDataBytesPerChunk)
ok = yaffs_CheckpointFlushBuffer(dev);
}
return i;
}
int yaffs_CheckpointRead(yaffs_Device *dev, void *data, int nBytes)
{
int i=0;
int ok = 1;
yaffs_ExtendedTags tags;
int chunk;
int realignedChunk;
__u8 *dataBytes = (__u8 *)data;
if(!dev->checkpointBuffer)
return 0;
if(dev->checkpointOpenForWrite)
return -1;
while(i < nBytes && ok) {
if(dev->checkpointByteOffset < 0 ||
dev->checkpointByteOffset >= dev->nDataBytesPerChunk) {
if(dev->checkpointCurrentBlock < 0){
yaffs_CheckpointFindNextCheckpointBlock(dev);
dev->checkpointCurrentChunk = 0;
}
if(dev->checkpointCurrentBlock < 0)
ok = 0;
else {
chunk = dev->checkpointCurrentBlock * dev->nChunksPerBlock +
dev->checkpointCurrentChunk;
realignedChunk = chunk - dev->chunkOffset;
/* read in the next chunk */
/* printf("read checkpoint page %d\n",dev->checkpointPage); */
dev->readChunkWithTagsFromNAND(dev, realignedChunk,
dev->checkpointBuffer,
&tags);
if(tags.chunkId != (dev->checkpointPageSequence + 1) ||
tags.sequenceNumber != YAFFS_SEQUENCE_CHECKPOINT_DATA)
ok = 0;
dev->checkpointByteOffset = 0;
dev->checkpointPageSequence++;
dev->checkpointCurrentChunk++;
if(dev->checkpointCurrentChunk >= dev->nChunksPerBlock)
dev->checkpointCurrentBlock = -1;
}
}
if(ok){
*dataBytes = dev->checkpointBuffer[dev->checkpointByteOffset];
dev->checkpointSum += *dataBytes;
dev->checkpointXor ^= *dataBytes;
dev->checkpointByteOffset++;
i++;
dataBytes++;
dev->checkpointByteCount++;
}
}
return i;
}
int yaffs_CheckpointClose(yaffs_Device *dev)
{
if(dev->checkpointOpenForWrite){
if(dev->checkpointByteOffset != 0)
yaffs_CheckpointFlushBuffer(dev);
} else {
int i;
for(i = 0; i < dev->blocksInCheckpoint && dev->checkpointBlockList[i] >= 0; i++){
yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,dev->checkpointBlockList[i]);
if(bi->blockState == YAFFS_BLOCK_STATE_EMPTY)
bi->blockState = YAFFS_BLOCK_STATE_CHECKPOINT;
else {
// Todo this looks odd...
}
}
YFREE(dev->checkpointBlockList);
dev->checkpointBlockList = NULL;
}
dev->nFreeChunks -= dev->blocksInCheckpoint * dev->nChunksPerBlock;
dev->nErasedBlocks -= dev->blocksInCheckpoint;
T(YAFFS_TRACE_CHECKPOINT,(TSTR("checkpoint byte count %d" TENDSTR),
dev->checkpointByteCount));
if(dev->checkpointBuffer){
/* free the buffer */
YFREE(dev->checkpointBuffer);
dev->checkpointBuffer = NULL;
return 1;
}
else
return 0;
}
int yaffs_CheckpointInvalidateStream(yaffs_Device *dev)
{
/* Erase the first checksum block */
T(YAFFS_TRACE_CHECKPOINT,(TSTR("checkpoint invalidate"TENDSTR)));
if(!yaffs_CheckpointSpaceOk(dev))
return 0;
return yaffs_CheckpointErase(dev);
}