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 1.3 2006-05-21 09:39:12 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;
84 dev->checkpointCurrentBlock = i;
85 T(YAFFS_TRACE_CHECKPOINT,(TSTR("allocating checkpt block %d"TENDSTR),i));
90 T(YAFFS_TRACE_CHECKPOINT,(TSTR("out of checkpt blocks"TENDSTR)));
92 dev->checkpointNextBlock = -1;
93 dev->checkpointCurrentBlock = -1;
96 static void yaffs_CheckpointFindNextCheckpointBlock(yaffs_Device *dev)
99 yaffs_ExtendedTags tags;
101 if(dev->blocksInCheckpoint < dev->checkpointMaxBlocks)
102 for(i = dev->checkpointNextBlock; i <= dev->endBlock; i++){
103 int chunk = i * dev->nChunksPerBlock;
105 dev->readChunkWithTagsFromNAND(dev,chunk,NULL,&tags);
107 if(tags.sequenceNumber == YAFFS_SEQUENCE_CHECKPOINT_DATA){
108 /* Right kind of block */
109 dev->checkpointNextBlock = tags.objectId;
110 dev->checkpointCurrentBlock = i;
111 dev->checkpointBlockList[dev->blocksInCheckpoint] = i;
112 dev->blocksInCheckpoint++;
113 T(YAFFS_TRACE_CHECKPOINT,(TSTR("found checkpt block %d"TENDSTR),i));
118 T(YAFFS_TRACE_CHECKPOINT,(TSTR("found no more checkpt blocks"TENDSTR)));
120 dev->checkpointNextBlock = -1;
121 dev->checkpointCurrentBlock = -1;
125 int yaffs_CheckpointOpen(yaffs_Device *dev, int forWriting)
128 /* Got the functions we need? */
129 if (!dev->writeChunkWithTagsToNAND ||
130 !dev->readChunkWithTagsFromNAND ||
131 !dev->eraseBlockInNAND ||
132 !dev->markNANDBlockBad)
135 if(forWriting && !yaffs_CheckpointSpaceOk(dev))
138 if(!dev->checkpointBuffer)
139 dev->checkpointBuffer = YMALLOC(dev->nBytesPerChunk);
140 if(!dev->checkpointBuffer)
144 dev->checkpointPageSequence = 0;
146 dev->checkpointOpenForWrite = forWriting;
148 dev->checkpointByteCount = 0;
149 dev->checkpointCurrentBlock = -1;
150 dev->checkpointCurrentChunk = -1;
151 dev->checkpointNextBlock = dev->startBlock;
153 /* Erase all the blocks in the checkpoint area */
155 memset(dev->checkpointBuffer,0,dev->nBytesPerChunk);
156 dev->checkpointByteOffset = 0;
157 return yaffs_CheckpointErase(dev);
162 /* Set to a value that will kick off a read */
163 dev->checkpointByteOffset = dev->nBytesPerChunk;
164 /* A checkpoint block list of 1 checkpoint block per 16 block is (hopefully)
165 * going to be way more than we need */
166 dev->blocksInCheckpoint = 0;
167 dev->checkpointMaxBlocks = (dev->endBlock - dev->startBlock)/16 + 2;
168 dev->checkpointBlockList = YMALLOC(sizeof(int) * dev->checkpointMaxBlocks);
169 for(i = 0; i < dev->checkpointMaxBlocks; i++)
170 dev->checkpointBlockList[i] = -1;
176 static int yaffs_CheckpointFlushBuffer(yaffs_Device *dev)
181 yaffs_ExtendedTags tags;
183 if(dev->checkpointCurrentBlock < 0){
184 yaffs_CheckpointFindNextErasedBlock(dev);
185 dev->checkpointCurrentChunk = 0;
188 if(dev->checkpointCurrentBlock < 0)
191 tags.chunkDeleted = 0;
192 tags.objectId = dev->checkpointNextBlock; /* Hint to next place to look */
193 tags.chunkId = dev->checkpointPageSequence + 1;
194 tags.sequenceNumber = YAFFS_SEQUENCE_CHECKPOINT_DATA;
195 tags.byteCount = dev->nBytesPerChunk;
197 chunk = dev->checkpointCurrentBlock * dev->nChunksPerBlock + dev->checkpointCurrentChunk;
199 dev->writeChunkWithTagsToNAND(dev,chunk,dev->checkpointBuffer,&tags);
200 dev->checkpointByteOffset = 0;
201 dev->checkpointPageSequence++;
202 dev->checkpointCurrentChunk++;
203 if(dev->checkpointCurrentChunk >= dev->nChunksPerBlock){
204 dev->checkpointCurrentChunk = 0;
205 dev->checkpointCurrentBlock = -1;
207 memset(dev->checkpointBuffer,0,dev->nBytesPerChunk);
213 int yaffs_CheckpointWrite(yaffs_Device *dev,const void *data, int nBytes)
219 __u8 * dataBytes = (__u8 *)data;
223 if(!dev->checkpointBuffer)
226 while(i < nBytes && ok) {
230 dev->checkpointBuffer[dev->checkpointByteOffset] = *dataBytes ;
231 dev->checkpointByteOffset++;
234 dev->checkpointByteCount++;
237 if(dev->checkpointByteOffset < 0 ||
238 dev->checkpointByteOffset >= dev->nBytesPerChunk)
239 ok = yaffs_CheckpointFlushBuffer(dev);
246 int yaffs_CheckpointRead(yaffs_Device *dev, void *data, int nBytes)
250 yaffs_ExtendedTags tags;
255 __u8 *dataBytes = (__u8 *)data;
257 if(!dev->checkpointBuffer)
260 while(i < nBytes && ok) {
263 if(dev->checkpointByteOffset < 0 ||
264 dev->checkpointByteOffset >= dev->nBytesPerChunk) {
266 if(dev->checkpointCurrentBlock < 0){
267 yaffs_CheckpointFindNextCheckpointBlock(dev);
268 dev->checkpointCurrentChunk = 0;
271 if(dev->checkpointCurrentBlock < 0)
275 chunk = dev->checkpointCurrentBlock * dev->nChunksPerBlock +
276 dev->checkpointCurrentChunk;
278 /* read in the next chunk */
279 /* printf("read checkpoint page %d\n",dev->checkpointPage); */
280 dev->readChunkWithTagsFromNAND(dev, chunk,
281 dev->checkpointBuffer,
284 if(tags.chunkId != (dev->checkpointPageSequence + 1) ||
285 tags.sequenceNumber != YAFFS_SEQUENCE_CHECKPOINT_DATA)
288 dev->checkpointByteOffset = 0;
289 dev->checkpointPageSequence++;
290 dev->checkpointCurrentChunk++;
292 if(dev->checkpointCurrentChunk >= dev->nChunksPerBlock)
293 dev->checkpointCurrentBlock = -1;
298 *dataBytes = dev->checkpointBuffer[dev->checkpointByteOffset];
299 dev->checkpointByteOffset++;
302 dev->checkpointByteCount++;
309 int yaffs_CheckpointClose(yaffs_Device *dev)
312 if(dev->checkpointOpenForWrite){
313 if(dev->checkpointByteOffset != 0)
314 yaffs_CheckpointFlushBuffer(dev);
317 for(i = 0; i < dev->blocksInCheckpoint && dev->checkpointBlockList[i] >= 0; i++){
318 yaffs_BlockInfo *bi = &dev->blockInfo[dev->checkpointBlockList[i]];
319 if(bi->blockState == YAFFS_BLOCK_STATE_EMPTY)
320 bi->blockState = YAFFS_BLOCK_STATE_CHECKPOINT;
322 // Todo this looks odd...
325 YFREE(dev->checkpointBlockList);
326 dev->checkpointBlockList = NULL;
329 dev->nFreeChunks -= dev->blocksInCheckpoint * dev->nChunksPerBlock;
330 dev->nErasedBlocks -= dev->blocksInCheckpoint;
333 T(YAFFS_TRACE_CHECKPOINT,(TSTR("checkpoint byte count %d" TENDSTR),
334 dev->checkpointByteCount));
336 if(dev->checkpointBuffer){
337 /* free the buffer */
338 YFREE(dev->checkpointBuffer);
339 dev->checkpointBuffer = NULL;
347 int yaffs_CheckpointInvalidateStream(yaffs_Device *dev)
349 /* Erase the first checksum block */
351 T(YAFFS_TRACE_CHECKPOINT,(TSTR("checkpoint invalidate"TENDSTR)));
353 if(!yaffs_CheckpointSpaceOk(dev))
356 return yaffs_CheckpointErase(dev);