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Diffstat (limited to 'fs/yaffs2/yaffs_checkptrw.c')
-rw-r--r--fs/yaffs2/yaffs_checkptrw.c404
1 files changed, 404 insertions, 0 deletions
diff --git a/fs/yaffs2/yaffs_checkptrw.c b/fs/yaffs2/yaffs_checkptrw.c
new file mode 100644
index 0000000..d3a811e
--- /dev/null
+++ b/fs/yaffs2/yaffs_checkptrw.c
@@ -0,0 +1,404 @@
+/*
+ * 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);
+}
+
+
+