2 * YAFFS: Yet another FFS. A NAND-flash specific file system.
4 * Copyright (C) 2002 Aleph One Ltd.
5 * for Toby Churchill Ltd and Brightstar Engineering
7 * Created by Charles Manning <charles@aleph1.co.uk>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
15 const char *yaffs_checkptrw_c_version =
16 "$Id: yaffs_checkptrw.c,v 1.8 2006-11-09 19:55:24 charles Exp $";
19 #include "yaffs_checkptrw.h"
22 static int yaffs_CheckpointSpaceOk(yaffs_Device *dev)
25 int blocksAvailable = dev->nErasedBlocks - dev->nReservedBlocks;
27 T(YAFFS_TRACE_CHECKPOINT,
28 (TSTR("checkpt blocks available = %d" TENDSTR),
32 return (blocksAvailable <= 0) ? 0 : 1;
37 static int yaffs_CheckpointErase(yaffs_Device *dev)
43 if(!dev->eraseBlockInNAND)
45 T(YAFFS_TRACE_CHECKPOINT,(TSTR("checking blocks %d to %d"TENDSTR),
46 dev->internalStartBlock,dev->internalEndBlock));
48 for(i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
49 yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,i);
50 if(bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT){
51 T(YAFFS_TRACE_CHECKPOINT,(TSTR("erasing checkpt block %d"TENDSTR),i));
52 if(dev->eraseBlockInNAND(dev,i)){
53 bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
55 dev->nFreeChunks += dev->nChunksPerBlock;
58 dev->markNANDBlockBad(dev,i);
59 bi->blockState = YAFFS_BLOCK_STATE_DEAD;
64 dev->blocksInCheckpoint = 0;
70 static void yaffs_CheckpointFindNextErasedBlock(yaffs_Device *dev)
73 int blocksAvailable = dev->nErasedBlocks - dev->nReservedBlocks;
74 T(YAFFS_TRACE_CHECKPOINT,
75 (TSTR("allocating checkpt block: erased %d reserved %d avail %d next %d "TENDSTR),
76 dev->nErasedBlocks,dev->nReservedBlocks,blocksAvailable,dev->checkpointNextBlock));
78 if(dev->checkpointNextBlock >= 0 &&
79 dev->checkpointNextBlock <= dev->internalEndBlock &&
82 for(i = dev->checkpointNextBlock; i <= dev->internalEndBlock; i++){
83 yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,i);
84 if(bi->blockState == YAFFS_BLOCK_STATE_EMPTY){
85 dev->checkpointNextBlock = i + 1;
86 dev->checkpointCurrentBlock = i;
87 T(YAFFS_TRACE_CHECKPOINT,(TSTR("allocating checkpt block %d"TENDSTR),i));
92 T(YAFFS_TRACE_CHECKPOINT,(TSTR("out of checkpt blocks"TENDSTR)));
94 dev->checkpointNextBlock = -1;
95 dev->checkpointCurrentBlock = -1;
98 static void yaffs_CheckpointFindNextCheckpointBlock(yaffs_Device *dev)
101 yaffs_ExtendedTags tags;
103 if(dev->blocksInCheckpoint < dev->checkpointMaxBlocks)
104 for(i = dev->checkpointNextBlock; i <= dev->internalEndBlock; i++){
105 int chunk = i * dev->nChunksPerBlock;
107 dev->readChunkWithTagsFromNAND(dev,chunk,NULL,&tags);
109 if(tags.sequenceNumber == YAFFS_SEQUENCE_CHECKPOINT_DATA){
110 /* Right kind of block */
111 dev->checkpointNextBlock = tags.objectId;
112 dev->checkpointCurrentBlock = i;
113 dev->checkpointBlockList[dev->blocksInCheckpoint] = i;
114 dev->blocksInCheckpoint++;
115 T(YAFFS_TRACE_CHECKPOINT,(TSTR("found checkpt block %d"TENDSTR),i));
120 T(YAFFS_TRACE_CHECKPOINT,(TSTR("found no more checkpt blocks"TENDSTR)));
122 dev->checkpointNextBlock = -1;
123 dev->checkpointCurrentBlock = -1;
127 int yaffs_CheckpointOpen(yaffs_Device *dev, int forWriting)
130 /* Got the functions we need? */
131 if (!dev->writeChunkWithTagsToNAND ||
132 !dev->readChunkWithTagsFromNAND ||
133 !dev->eraseBlockInNAND ||
134 !dev->markNANDBlockBad)
137 if(forWriting && !yaffs_CheckpointSpaceOk(dev))
140 if(!dev->checkpointBuffer)
141 dev->checkpointBuffer = YMALLOC_DMA(dev->nDataBytesPerChunk);
142 if(!dev->checkpointBuffer)
146 dev->checkpointPageSequence = 0;
148 dev->checkpointOpenForWrite = forWriting;
150 dev->checkpointByteCount = 0;
151 dev->checkpointCurrentBlock = -1;
152 dev->checkpointCurrentChunk = -1;
153 dev->checkpointNextBlock = dev->internalStartBlock;
155 /* Erase all the blocks in the checkpoint area */
157 memset(dev->checkpointBuffer,0,dev->nDataBytesPerChunk);
158 dev->checkpointByteOffset = 0;
159 return yaffs_CheckpointErase(dev);
164 /* Set to a value that will kick off a read */
165 dev->checkpointByteOffset = dev->nDataBytesPerChunk;
166 /* A checkpoint block list of 1 checkpoint block per 16 block is (hopefully)
167 * going to be way more than we need */
168 dev->blocksInCheckpoint = 0;
169 dev->checkpointMaxBlocks = (dev->internalEndBlock - dev->internalStartBlock)/16 + 2;
170 dev->checkpointBlockList = YMALLOC(sizeof(int) * dev->checkpointMaxBlocks);
171 for(i = 0; i < dev->checkpointMaxBlocks; i++)
172 dev->checkpointBlockList[i] = -1;
178 static int yaffs_CheckpointFlushBuffer(yaffs_Device *dev)
183 yaffs_ExtendedTags tags;
185 if(dev->checkpointCurrentBlock < 0){
186 yaffs_CheckpointFindNextErasedBlock(dev);
187 dev->checkpointCurrentChunk = 0;
190 if(dev->checkpointCurrentBlock < 0)
193 tags.chunkDeleted = 0;
194 tags.objectId = dev->checkpointNextBlock; /* Hint to next place to look */
195 tags.chunkId = dev->checkpointPageSequence + 1;
196 tags.sequenceNumber = YAFFS_SEQUENCE_CHECKPOINT_DATA;
197 tags.byteCount = dev->nDataBytesPerChunk;
198 if(dev->checkpointCurrentChunk == 0){
199 /* First chunk we write for the block? Set block state to
201 yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,dev->checkpointCurrentBlock);
202 bi->blockState = YAFFS_BLOCK_STATE_CHECKPOINT;
203 dev->blocksInCheckpoint++;
206 chunk = dev->checkpointCurrentBlock * dev->nChunksPerBlock + dev->checkpointCurrentChunk;
208 dev->writeChunkWithTagsToNAND(dev,chunk,dev->checkpointBuffer,&tags);
209 dev->checkpointByteOffset = 0;
210 dev->checkpointPageSequence++;
211 dev->checkpointCurrentChunk++;
212 if(dev->checkpointCurrentChunk >= dev->nChunksPerBlock){
213 dev->checkpointCurrentChunk = 0;
214 dev->checkpointCurrentBlock = -1;
216 memset(dev->checkpointBuffer,0,dev->nDataBytesPerChunk);
222 int yaffs_CheckpointWrite(yaffs_Device *dev,const void *data, int nBytes)
228 __u8 * dataBytes = (__u8 *)data;
232 if(!dev->checkpointBuffer)
235 while(i < nBytes && ok) {
239 dev->checkpointBuffer[dev->checkpointByteOffset] = *dataBytes ;
240 dev->checkpointByteOffset++;
243 dev->checkpointByteCount++;
246 if(dev->checkpointByteOffset < 0 ||
247 dev->checkpointByteOffset >= dev->nDataBytesPerChunk)
248 ok = yaffs_CheckpointFlushBuffer(dev);
255 int yaffs_CheckpointRead(yaffs_Device *dev, void *data, int nBytes)
259 yaffs_ExtendedTags tags;
264 __u8 *dataBytes = (__u8 *)data;
266 if(!dev->checkpointBuffer)
269 while(i < nBytes && ok) {
272 if(dev->checkpointByteOffset < 0 ||
273 dev->checkpointByteOffset >= dev->nDataBytesPerChunk) {
275 if(dev->checkpointCurrentBlock < 0){
276 yaffs_CheckpointFindNextCheckpointBlock(dev);
277 dev->checkpointCurrentChunk = 0;
280 if(dev->checkpointCurrentBlock < 0)
284 chunk = dev->checkpointCurrentBlock * dev->nChunksPerBlock +
285 dev->checkpointCurrentChunk;
287 /* read in the next chunk */
288 /* printf("read checkpoint page %d\n",dev->checkpointPage); */
289 dev->readChunkWithTagsFromNAND(dev, chunk,
290 dev->checkpointBuffer,
293 if(tags.chunkId != (dev->checkpointPageSequence + 1) ||
294 tags.sequenceNumber != YAFFS_SEQUENCE_CHECKPOINT_DATA)
297 dev->checkpointByteOffset = 0;
298 dev->checkpointPageSequence++;
299 dev->checkpointCurrentChunk++;
301 if(dev->checkpointCurrentChunk >= dev->nChunksPerBlock)
302 dev->checkpointCurrentBlock = -1;
307 *dataBytes = dev->checkpointBuffer[dev->checkpointByteOffset];
308 dev->checkpointByteOffset++;
311 dev->checkpointByteCount++;
318 int yaffs_CheckpointClose(yaffs_Device *dev)
321 if(dev->checkpointOpenForWrite){
322 if(dev->checkpointByteOffset != 0)
323 yaffs_CheckpointFlushBuffer(dev);
326 for(i = 0; i < dev->blocksInCheckpoint && dev->checkpointBlockList[i] >= 0; i++){
327 yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,dev->checkpointBlockList[i]);
328 if(bi->blockState == YAFFS_BLOCK_STATE_EMPTY)
329 bi->blockState = YAFFS_BLOCK_STATE_CHECKPOINT;
331 // Todo this looks odd...
334 YFREE(dev->checkpointBlockList);
335 dev->checkpointBlockList = NULL;
338 dev->nFreeChunks -= dev->blocksInCheckpoint * dev->nChunksPerBlock;
339 dev->nErasedBlocks -= dev->blocksInCheckpoint;
342 T(YAFFS_TRACE_CHECKPOINT,(TSTR("checkpoint byte count %d" TENDSTR),
343 dev->checkpointByteCount));
345 if(dev->checkpointBuffer){
346 /* free the buffer */
347 YFREE(dev->checkpointBuffer);
348 dev->checkpointBuffer = NULL;
356 int yaffs_CheckpointInvalidateStream(yaffs_Device *dev)
358 /* Erase the first checksum block */
360 T(YAFFS_TRACE_CHECKPOINT,(TSTR("checkpoint invalidate"TENDSTR)));
362 if(!yaffs_CheckpointSpaceOk(dev))
365 return yaffs_CheckpointErase(dev);