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 1.4 2006-05-23 19:08:41 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->startBlock,dev->endBlock));
48 for(i = dev->startBlock; i <= dev->endBlock; i++) {
49 yaffs_BlockInfo *bi = &dev->blockInfo[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;
75 if(dev->checkpointNextBlock >= 0 &&
76 dev->checkpointNextBlock <= dev->endBlock &&
79 for(i = dev->checkpointNextBlock; i <= dev->endBlock; i++){
80 yaffs_BlockInfo *bi = &dev->blockInfo[i];
81 if(bi->blockState == YAFFS_BLOCK_STATE_EMPTY){
82 dev->checkpointNextBlock = i + 1;
83 dev->checkpointCurrentBlock = i;
84 T(YAFFS_TRACE_CHECKPOINT,(TSTR("allocating checkpt block %d"TENDSTR),i));
89 T(YAFFS_TRACE_CHECKPOINT,(TSTR("out of checkpt blocks"TENDSTR)));
91 dev->checkpointNextBlock = -1;
92 dev->checkpointCurrentBlock = -1;
95 static void yaffs_CheckpointFindNextCheckpointBlock(yaffs_Device *dev)
98 yaffs_ExtendedTags tags;
100 if(dev->blocksInCheckpoint < dev->checkpointMaxBlocks)
101 for(i = dev->checkpointNextBlock; i <= dev->endBlock; i++){
102 int chunk = i * dev->nChunksPerBlock;
104 dev->readChunkWithTagsFromNAND(dev,chunk,NULL,&tags);
106 if(tags.sequenceNumber == YAFFS_SEQUENCE_CHECKPOINT_DATA){
107 /* Right kind of block */
108 dev->checkpointNextBlock = tags.objectId;
109 dev->checkpointCurrentBlock = i;
110 dev->checkpointBlockList[dev->blocksInCheckpoint] = i;
111 dev->blocksInCheckpoint++;
112 T(YAFFS_TRACE_CHECKPOINT,(TSTR("found checkpt block %d"TENDSTR),i));
117 T(YAFFS_TRACE_CHECKPOINT,(TSTR("found no more checkpt blocks"TENDSTR)));
119 dev->checkpointNextBlock = -1;
120 dev->checkpointCurrentBlock = -1;
124 int yaffs_CheckpointOpen(yaffs_Device *dev, int forWriting)
127 /* Got the functions we need? */
128 if (!dev->writeChunkWithTagsToNAND ||
129 !dev->readChunkWithTagsFromNAND ||
130 !dev->eraseBlockInNAND ||
131 !dev->markNANDBlockBad)
134 if(forWriting && !yaffs_CheckpointSpaceOk(dev))
137 if(!dev->checkpointBuffer)
138 dev->checkpointBuffer = YMALLOC_DMA(dev->nBytesPerChunk);
139 if(!dev->checkpointBuffer)
143 dev->checkpointPageSequence = 0;
145 dev->checkpointOpenForWrite = forWriting;
147 dev->checkpointByteCount = 0;
148 dev->checkpointCurrentBlock = -1;
149 dev->checkpointCurrentChunk = -1;
150 dev->checkpointNextBlock = dev->startBlock;
152 /* Erase all the blocks in the checkpoint area */
154 memset(dev->checkpointBuffer,0,dev->nBytesPerChunk);
155 dev->checkpointByteOffset = 0;
156 return yaffs_CheckpointErase(dev);
161 /* Set to a value that will kick off a read */
162 dev->checkpointByteOffset = dev->nBytesPerChunk;
163 /* A checkpoint block list of 1 checkpoint block per 16 block is (hopefully)
164 * going to be way more than we need */
165 dev->blocksInCheckpoint = 0;
166 dev->checkpointMaxBlocks = (dev->endBlock - dev->startBlock)/16 + 2;
167 dev->checkpointBlockList = YMALLOC(sizeof(int) * dev->checkpointMaxBlocks);
168 for(i = 0; i < dev->checkpointMaxBlocks; i++)
169 dev->checkpointBlockList[i] = -1;
175 static int yaffs_CheckpointFlushBuffer(yaffs_Device *dev)
180 yaffs_ExtendedTags tags;
182 if(dev->checkpointCurrentBlock < 0){
183 yaffs_CheckpointFindNextErasedBlock(dev);
184 dev->checkpointCurrentChunk = 0;
187 if(dev->checkpointCurrentBlock < 0)
190 tags.chunkDeleted = 0;
191 tags.objectId = dev->checkpointNextBlock; /* Hint to next place to look */
192 tags.chunkId = dev->checkpointPageSequence + 1;
193 tags.sequenceNumber = YAFFS_SEQUENCE_CHECKPOINT_DATA;
194 tags.byteCount = dev->nBytesPerChunk;
195 if(dev->checkpointCurrentChunk == 0){
196 /* First chunk we write for the block? Set block state to
198 yaffs_BlockInfo *bi = &dev->blockInfo[dev->checkpointCurrentBlock];
199 bi->blockState = YAFFS_BLOCK_STATE_CHECKPOINT;
200 dev->blocksInCheckpoint++;
203 chunk = dev->checkpointCurrentBlock * dev->nChunksPerBlock + dev->checkpointCurrentChunk;
205 dev->writeChunkWithTagsToNAND(dev,chunk,dev->checkpointBuffer,&tags);
206 dev->checkpointByteOffset = 0;
207 dev->checkpointPageSequence++;
208 dev->checkpointCurrentChunk++;
209 if(dev->checkpointCurrentChunk >= dev->nChunksPerBlock){
210 dev->checkpointCurrentChunk = 0;
211 dev->checkpointCurrentBlock = -1;
213 memset(dev->checkpointBuffer,0,dev->nBytesPerChunk);
219 int yaffs_CheckpointWrite(yaffs_Device *dev,const void *data, int nBytes)
225 __u8 * dataBytes = (__u8 *)data;
229 if(!dev->checkpointBuffer)
232 while(i < nBytes && ok) {
236 dev->checkpointBuffer[dev->checkpointByteOffset] = *dataBytes ;
237 dev->checkpointByteOffset++;
240 dev->checkpointByteCount++;
243 if(dev->checkpointByteOffset < 0 ||
244 dev->checkpointByteOffset >= dev->nBytesPerChunk)
245 ok = yaffs_CheckpointFlushBuffer(dev);
252 int yaffs_CheckpointRead(yaffs_Device *dev, void *data, int nBytes)
256 yaffs_ExtendedTags tags;
261 __u8 *dataBytes = (__u8 *)data;
263 if(!dev->checkpointBuffer)
266 while(i < nBytes && ok) {
269 if(dev->checkpointByteOffset < 0 ||
270 dev->checkpointByteOffset >= dev->nBytesPerChunk) {
272 if(dev->checkpointCurrentBlock < 0){
273 yaffs_CheckpointFindNextCheckpointBlock(dev);
274 dev->checkpointCurrentChunk = 0;
277 if(dev->checkpointCurrentBlock < 0)
281 chunk = dev->checkpointCurrentBlock * dev->nChunksPerBlock +
282 dev->checkpointCurrentChunk;
284 /* read in the next chunk */
285 /* printf("read checkpoint page %d\n",dev->checkpointPage); */
286 dev->readChunkWithTagsFromNAND(dev, chunk,
287 dev->checkpointBuffer,
290 if(tags.chunkId != (dev->checkpointPageSequence + 1) ||
291 tags.sequenceNumber != YAFFS_SEQUENCE_CHECKPOINT_DATA)
294 dev->checkpointByteOffset = 0;
295 dev->checkpointPageSequence++;
296 dev->checkpointCurrentChunk++;
298 if(dev->checkpointCurrentChunk >= dev->nChunksPerBlock)
299 dev->checkpointCurrentBlock = -1;
304 *dataBytes = dev->checkpointBuffer[dev->checkpointByteOffset];
305 dev->checkpointByteOffset++;
308 dev->checkpointByteCount++;
315 int yaffs_CheckpointClose(yaffs_Device *dev)
318 if(dev->checkpointOpenForWrite){
319 if(dev->checkpointByteOffset != 0)
320 yaffs_CheckpointFlushBuffer(dev);
323 for(i = 0; i < dev->blocksInCheckpoint && dev->checkpointBlockList[i] >= 0; i++){
324 yaffs_BlockInfo *bi = &dev->blockInfo[dev->checkpointBlockList[i]];
325 if(bi->blockState == YAFFS_BLOCK_STATE_EMPTY)
326 bi->blockState = YAFFS_BLOCK_STATE_CHECKPOINT;
328 // Todo this looks odd...
331 YFREE(dev->checkpointBlockList);
332 dev->checkpointBlockList = NULL;
335 dev->nFreeChunks -= dev->blocksInCheckpoint * dev->nChunksPerBlock;
336 dev->nErasedBlocks -= dev->blocksInCheckpoint;
339 T(YAFFS_TRACE_CHECKPOINT,(TSTR("checkpoint byte count %d" TENDSTR),
340 dev->checkpointByteCount));
342 if(dev->checkpointBuffer){
343 /* free the buffer */
344 YFREE(dev->checkpointBuffer);
345 dev->checkpointBuffer = NULL;
353 int yaffs_CheckpointInvalidateStream(yaffs_Device *dev)
355 /* Erase the first checksum block */
357 T(YAFFS_TRACE_CHECKPOINT,(TSTR("checkpoint invalidate"TENDSTR)));
359 if(!yaffs_CheckpointSpaceOk(dev))
362 return yaffs_CheckpointErase(dev);