[8.09] [kernel] generic-2.6: rename "files" directory to "files-2.6.24" to be consistent
[openwrt/svn-archive/archive.git] / target / linux / generic-2.6 / files-2.6.24 / fs / yaffs2 / yaffs_checkptrw.c
1 /*
2 * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
3 *
4 * Copyright (C) 2002-2007 Aleph One Ltd.
5 * for Toby Churchill Ltd and Brightstar Engineering
6 *
7 * Created by Charles Manning <charles@aleph1.co.uk>
8 *
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.
12 */
13
14 const char *yaffs_checkptrw_c_version =
15 "$Id: yaffs_checkptrw.c,v 1.14 2007-05-15 20:07:40 charles Exp $";
16
17
18 #include "yaffs_checkptrw.h"
19
20
21 static int yaffs_CheckpointSpaceOk(yaffs_Device *dev)
22 {
23
24 int blocksAvailable = dev->nErasedBlocks - dev->nReservedBlocks;
25
26 T(YAFFS_TRACE_CHECKPOINT,
27 (TSTR("checkpt blocks available = %d" TENDSTR),
28 blocksAvailable));
29
30
31 return (blocksAvailable <= 0) ? 0 : 1;
32 }
33
34
35 static int yaffs_CheckpointErase(yaffs_Device *dev)
36 {
37
38 int i;
39
40
41 if(!dev->eraseBlockInNAND)
42 return 0;
43 T(YAFFS_TRACE_CHECKPOINT,(TSTR("checking blocks %d to %d"TENDSTR),
44 dev->internalStartBlock,dev->internalEndBlock));
45
46 for(i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
47 yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,i);
48 if(bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT){
49 T(YAFFS_TRACE_CHECKPOINT,(TSTR("erasing checkpt block %d"TENDSTR),i));
50 if(dev->eraseBlockInNAND(dev,i- dev->blockOffset /* realign */)){
51 bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
52 dev->nErasedBlocks++;
53 dev->nFreeChunks += dev->nChunksPerBlock;
54 }
55 else {
56 dev->markNANDBlockBad(dev,i);
57 bi->blockState = YAFFS_BLOCK_STATE_DEAD;
58 }
59 }
60 }
61
62 dev->blocksInCheckpoint = 0;
63
64 return 1;
65 }
66
67
68 static void yaffs_CheckpointFindNextErasedBlock(yaffs_Device *dev)
69 {
70 int i;
71 int blocksAvailable = dev->nErasedBlocks - dev->nReservedBlocks;
72 T(YAFFS_TRACE_CHECKPOINT,
73 (TSTR("allocating checkpt block: erased %d reserved %d avail %d next %d "TENDSTR),
74 dev->nErasedBlocks,dev->nReservedBlocks,blocksAvailable,dev->checkpointNextBlock));
75
76 if(dev->checkpointNextBlock >= 0 &&
77 dev->checkpointNextBlock <= dev->internalEndBlock &&
78 blocksAvailable > 0){
79
80 for(i = dev->checkpointNextBlock; i <= dev->internalEndBlock; i++){
81 yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,i);
82 if(bi->blockState == YAFFS_BLOCK_STATE_EMPTY){
83 dev->checkpointNextBlock = i + 1;
84 dev->checkpointCurrentBlock = i;
85 T(YAFFS_TRACE_CHECKPOINT,(TSTR("allocating checkpt block %d"TENDSTR),i));
86 return;
87 }
88 }
89 }
90 T(YAFFS_TRACE_CHECKPOINT,(TSTR("out of checkpt blocks"TENDSTR)));
91
92 dev->checkpointNextBlock = -1;
93 dev->checkpointCurrentBlock = -1;
94 }
95
96 static void yaffs_CheckpointFindNextCheckpointBlock(yaffs_Device *dev)
97 {
98 int i;
99 yaffs_ExtendedTags tags;
100
101 T(YAFFS_TRACE_CHECKPOINT,(TSTR("find next checkpt block: start: blocks %d next %d" TENDSTR),
102 dev->blocksInCheckpoint, dev->checkpointNextBlock));
103
104 if(dev->blocksInCheckpoint < dev->checkpointMaxBlocks)
105 for(i = dev->checkpointNextBlock; i <= dev->internalEndBlock; i++){
106 int chunk = i * dev->nChunksPerBlock;
107 int realignedChunk = chunk - dev->chunkOffset;
108
109 dev->readChunkWithTagsFromNAND(dev,realignedChunk,NULL,&tags);
110 T(YAFFS_TRACE_CHECKPOINT,(TSTR("find next checkpt block: search: block %d oid %d seq %d eccr %d" TENDSTR),
111 i, tags.objectId,tags.sequenceNumber,tags.eccResult));
112
113 if(tags.sequenceNumber == YAFFS_SEQUENCE_CHECKPOINT_DATA){
114 /* Right kind of block */
115 dev->checkpointNextBlock = tags.objectId;
116 dev->checkpointCurrentBlock = i;
117 dev->checkpointBlockList[dev->blocksInCheckpoint] = i;
118 dev->blocksInCheckpoint++;
119 T(YAFFS_TRACE_CHECKPOINT,(TSTR("found checkpt block %d"TENDSTR),i));
120 return;
121 }
122 }
123
124 T(YAFFS_TRACE_CHECKPOINT,(TSTR("found no more checkpt blocks"TENDSTR)));
125
126 dev->checkpointNextBlock = -1;
127 dev->checkpointCurrentBlock = -1;
128 }
129
130
131 int yaffs_CheckpointOpen(yaffs_Device *dev, int forWriting)
132 {
133
134 /* Got the functions we need? */
135 if (!dev->writeChunkWithTagsToNAND ||
136 !dev->readChunkWithTagsFromNAND ||
137 !dev->eraseBlockInNAND ||
138 !dev->markNANDBlockBad)
139 return 0;
140
141 if(forWriting && !yaffs_CheckpointSpaceOk(dev))
142 return 0;
143
144 if(!dev->checkpointBuffer)
145 dev->checkpointBuffer = YMALLOC_DMA(dev->nDataBytesPerChunk);
146 if(!dev->checkpointBuffer)
147 return 0;
148
149
150 dev->checkpointPageSequence = 0;
151
152 dev->checkpointOpenForWrite = forWriting;
153
154 dev->checkpointByteCount = 0;
155 dev->checkpointSum = 0;
156 dev->checkpointXor = 0;
157 dev->checkpointCurrentBlock = -1;
158 dev->checkpointCurrentChunk = -1;
159 dev->checkpointNextBlock = dev->internalStartBlock;
160
161 /* Erase all the blocks in the checkpoint area */
162 if(forWriting){
163 memset(dev->checkpointBuffer,0,dev->nDataBytesPerChunk);
164 dev->checkpointByteOffset = 0;
165 return yaffs_CheckpointErase(dev);
166
167
168 } else {
169 int i;
170 /* Set to a value that will kick off a read */
171 dev->checkpointByteOffset = dev->nDataBytesPerChunk;
172 /* A checkpoint block list of 1 checkpoint block per 16 block is (hopefully)
173 * going to be way more than we need */
174 dev->blocksInCheckpoint = 0;
175 dev->checkpointMaxBlocks = (dev->internalEndBlock - dev->internalStartBlock)/16 + 2;
176 dev->checkpointBlockList = YMALLOC(sizeof(int) * dev->checkpointMaxBlocks);
177 for(i = 0; i < dev->checkpointMaxBlocks; i++)
178 dev->checkpointBlockList[i] = -1;
179 }
180
181 return 1;
182 }
183
184 int yaffs_GetCheckpointSum(yaffs_Device *dev, __u32 *sum)
185 {
186 __u32 compositeSum;
187 compositeSum = (dev->checkpointSum << 8) | (dev->checkpointXor & 0xFF);
188 *sum = compositeSum;
189 return 1;
190 }
191
192 static int yaffs_CheckpointFlushBuffer(yaffs_Device *dev)
193 {
194
195 int chunk;
196 int realignedChunk;
197
198 yaffs_ExtendedTags tags;
199
200 if(dev->checkpointCurrentBlock < 0){
201 yaffs_CheckpointFindNextErasedBlock(dev);
202 dev->checkpointCurrentChunk = 0;
203 }
204
205 if(dev->checkpointCurrentBlock < 0)
206 return 0;
207
208 tags.chunkDeleted = 0;
209 tags.objectId = dev->checkpointNextBlock; /* Hint to next place to look */
210 tags.chunkId = dev->checkpointPageSequence + 1;
211 tags.sequenceNumber = YAFFS_SEQUENCE_CHECKPOINT_DATA;
212 tags.byteCount = dev->nDataBytesPerChunk;
213 if(dev->checkpointCurrentChunk == 0){
214 /* First chunk we write for the block? Set block state to
215 checkpoint */
216 yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,dev->checkpointCurrentBlock);
217 bi->blockState = YAFFS_BLOCK_STATE_CHECKPOINT;
218 dev->blocksInCheckpoint++;
219 }
220
221 chunk = dev->checkpointCurrentBlock * dev->nChunksPerBlock + dev->checkpointCurrentChunk;
222
223
224 T(YAFFS_TRACE_CHECKPOINT,(TSTR("checkpoint wite buffer nand %d(%d:%d) objid %d chId %d" TENDSTR),
225 chunk, dev->checkpointCurrentBlock, dev->checkpointCurrentChunk,tags.objectId,tags.chunkId));
226
227 realignedChunk = chunk - dev->chunkOffset;
228
229 dev->writeChunkWithTagsToNAND(dev,realignedChunk,dev->checkpointBuffer,&tags);
230 dev->checkpointByteOffset = 0;
231 dev->checkpointPageSequence++;
232 dev->checkpointCurrentChunk++;
233 if(dev->checkpointCurrentChunk >= dev->nChunksPerBlock){
234 dev->checkpointCurrentChunk = 0;
235 dev->checkpointCurrentBlock = -1;
236 }
237 memset(dev->checkpointBuffer,0,dev->nDataBytesPerChunk);
238
239 return 1;
240 }
241
242
243 int yaffs_CheckpointWrite(yaffs_Device *dev,const void *data, int nBytes)
244 {
245 int i=0;
246 int ok = 1;
247
248
249 __u8 * dataBytes = (__u8 *)data;
250
251
252
253 if(!dev->checkpointBuffer)
254 return 0;
255
256 if(!dev->checkpointOpenForWrite)
257 return -1;
258
259 while(i < nBytes && ok) {
260
261
262
263 dev->checkpointBuffer[dev->checkpointByteOffset] = *dataBytes ;
264 dev->checkpointSum += *dataBytes;
265 dev->checkpointXor ^= *dataBytes;
266
267 dev->checkpointByteOffset++;
268 i++;
269 dataBytes++;
270 dev->checkpointByteCount++;
271
272
273 if(dev->checkpointByteOffset < 0 ||
274 dev->checkpointByteOffset >= dev->nDataBytesPerChunk)
275 ok = yaffs_CheckpointFlushBuffer(dev);
276
277 }
278
279 return i;
280 }
281
282 int yaffs_CheckpointRead(yaffs_Device *dev, void *data, int nBytes)
283 {
284 int i=0;
285 int ok = 1;
286 yaffs_ExtendedTags tags;
287
288
289 int chunk;
290 int realignedChunk;
291
292 __u8 *dataBytes = (__u8 *)data;
293
294 if(!dev->checkpointBuffer)
295 return 0;
296
297 if(dev->checkpointOpenForWrite)
298 return -1;
299
300 while(i < nBytes && ok) {
301
302
303 if(dev->checkpointByteOffset < 0 ||
304 dev->checkpointByteOffset >= dev->nDataBytesPerChunk) {
305
306 if(dev->checkpointCurrentBlock < 0){
307 yaffs_CheckpointFindNextCheckpointBlock(dev);
308 dev->checkpointCurrentChunk = 0;
309 }
310
311 if(dev->checkpointCurrentBlock < 0)
312 ok = 0;
313 else {
314
315 chunk = dev->checkpointCurrentBlock * dev->nChunksPerBlock +
316 dev->checkpointCurrentChunk;
317
318 realignedChunk = chunk - dev->chunkOffset;
319
320 /* read in the next chunk */
321 /* printf("read checkpoint page %d\n",dev->checkpointPage); */
322 dev->readChunkWithTagsFromNAND(dev, realignedChunk,
323 dev->checkpointBuffer,
324 &tags);
325
326 if(tags.chunkId != (dev->checkpointPageSequence + 1) ||
327 tags.sequenceNumber != YAFFS_SEQUENCE_CHECKPOINT_DATA)
328 ok = 0;
329
330 dev->checkpointByteOffset = 0;
331 dev->checkpointPageSequence++;
332 dev->checkpointCurrentChunk++;
333
334 if(dev->checkpointCurrentChunk >= dev->nChunksPerBlock)
335 dev->checkpointCurrentBlock = -1;
336 }
337 }
338
339 if(ok){
340 *dataBytes = dev->checkpointBuffer[dev->checkpointByteOffset];
341 dev->checkpointSum += *dataBytes;
342 dev->checkpointXor ^= *dataBytes;
343 dev->checkpointByteOffset++;
344 i++;
345 dataBytes++;
346 dev->checkpointByteCount++;
347 }
348 }
349
350 return i;
351 }
352
353 int yaffs_CheckpointClose(yaffs_Device *dev)
354 {
355
356 if(dev->checkpointOpenForWrite){
357 if(dev->checkpointByteOffset != 0)
358 yaffs_CheckpointFlushBuffer(dev);
359 } else {
360 int i;
361 for(i = 0; i < dev->blocksInCheckpoint && dev->checkpointBlockList[i] >= 0; i++){
362 yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev,dev->checkpointBlockList[i]);
363 if(bi->blockState == YAFFS_BLOCK_STATE_EMPTY)
364 bi->blockState = YAFFS_BLOCK_STATE_CHECKPOINT;
365 else {
366 // Todo this looks odd...
367 }
368 }
369 YFREE(dev->checkpointBlockList);
370 dev->checkpointBlockList = NULL;
371 }
372
373 dev->nFreeChunks -= dev->blocksInCheckpoint * dev->nChunksPerBlock;
374 dev->nErasedBlocks -= dev->blocksInCheckpoint;
375
376
377 T(YAFFS_TRACE_CHECKPOINT,(TSTR("checkpoint byte count %d" TENDSTR),
378 dev->checkpointByteCount));
379
380 if(dev->checkpointBuffer){
381 /* free the buffer */
382 YFREE(dev->checkpointBuffer);
383 dev->checkpointBuffer = NULL;
384 return 1;
385 }
386 else
387 return 0;
388
389 }
390
391 int yaffs_CheckpointInvalidateStream(yaffs_Device *dev)
392 {
393 /* Erase the first checksum block */
394
395 T(YAFFS_TRACE_CHECKPOINT,(TSTR("checkpoint invalidate"TENDSTR)));
396
397 if(!yaffs_CheckpointSpaceOk(dev))
398 return 0;
399
400 return yaffs_CheckpointErase(dev);
401 }
402
403
404