/fs/yaffs2/yaffs_checkptrw.c

https://github.com/jasonts/htc-kernel-msm7227-exp · C · 401 lines · 283 code · 93 blank · 25 comment · 60 complexity · ecfcc3db4ebcb7ed0e5a62e92eb628a3 MD5 · raw file

  1. /*
  2. * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
  3. *
  4. * Copyright (C) 2002-2010 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. #include "yaffs_checkptrw.h"
  14. #include "yaffs_getblockinfo.h"
  15. static int yaffs2_CheckpointSpaceOk(yaffs_Device *dev)
  16. {
  17. int blocksAvailable = dev->nErasedBlocks - dev->param.nReservedBlocks;
  18. T(YAFFS_TRACE_CHECKPOINT,
  19. (TSTR("checkpt blocks available = %d" TENDSTR),
  20. blocksAvailable));
  21. return (blocksAvailable <= 0) ? 0 : 1;
  22. }
  23. static int yaffs2_CheckpointErase(yaffs_Device *dev)
  24. {
  25. int i;
  26. if (!dev->param.eraseBlockInNAND)
  27. return 0;
  28. T(YAFFS_TRACE_CHECKPOINT, (TSTR("checking blocks %d to %d"TENDSTR),
  29. dev->internalStartBlock, dev->internalEndBlock));
  30. for (i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
  31. yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, i);
  32. if (bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT) {
  33. T(YAFFS_TRACE_CHECKPOINT, (TSTR("erasing checkpt block %d"TENDSTR), i));
  34. dev->nBlockErasures++;
  35. if (dev->param.eraseBlockInNAND(dev, i - dev->blockOffset /* realign */)) {
  36. bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
  37. dev->nErasedBlocks++;
  38. dev->nFreeChunks += dev->param.nChunksPerBlock;
  39. } else {
  40. dev->param.markNANDBlockBad(dev, i);
  41. bi->blockState = YAFFS_BLOCK_STATE_DEAD;
  42. }
  43. }
  44. }
  45. dev->blocksInCheckpoint = 0;
  46. return 1;
  47. }
  48. static void yaffs2_CheckpointFindNextErasedBlock(yaffs_Device *dev)
  49. {
  50. int i;
  51. int blocksAvailable = dev->nErasedBlocks - dev->param.nReservedBlocks;
  52. T(YAFFS_TRACE_CHECKPOINT,
  53. (TSTR("allocating checkpt block: erased %d reserved %d avail %d next %d "TENDSTR),
  54. dev->nErasedBlocks, dev->param.nReservedBlocks, blocksAvailable, dev->checkpointNextBlock));
  55. if (dev->checkpointNextBlock >= 0 &&
  56. dev->checkpointNextBlock <= dev->internalEndBlock &&
  57. blocksAvailable > 0) {
  58. for (i = dev->checkpointNextBlock; i <= dev->internalEndBlock; i++) {
  59. yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, i);
  60. if (bi->blockState == YAFFS_BLOCK_STATE_EMPTY) {
  61. dev->checkpointNextBlock = i + 1;
  62. dev->checkpointCurrentBlock = i;
  63. T(YAFFS_TRACE_CHECKPOINT, (TSTR("allocating checkpt block %d"TENDSTR), i));
  64. return;
  65. }
  66. }
  67. }
  68. T(YAFFS_TRACE_CHECKPOINT, (TSTR("out of checkpt blocks"TENDSTR)));
  69. dev->checkpointNextBlock = -1;
  70. dev->checkpointCurrentBlock = -1;
  71. }
  72. static void yaffs2_CheckpointFindNextCheckpointBlock(yaffs_Device *dev)
  73. {
  74. int i;
  75. yaffs_ExtendedTags tags;
  76. T(YAFFS_TRACE_CHECKPOINT, (TSTR("find next checkpt block: start: blocks %d next %d" TENDSTR),
  77. dev->blocksInCheckpoint, dev->checkpointNextBlock));
  78. if (dev->blocksInCheckpoint < dev->checkpointMaxBlocks)
  79. for (i = dev->checkpointNextBlock; i <= dev->internalEndBlock; i++) {
  80. int chunk = i * dev->param.nChunksPerBlock;
  81. int realignedChunk = chunk - dev->chunkOffset;
  82. dev->param.readChunkWithTagsFromNAND(dev, realignedChunk,
  83. NULL, &tags);
  84. T(YAFFS_TRACE_CHECKPOINT, (TSTR("find next checkpt block: search: block %d oid %d seq %d eccr %d" TENDSTR),
  85. i, tags.objectId, tags.sequenceNumber, tags.eccResult));
  86. if (tags.sequenceNumber == YAFFS_SEQUENCE_CHECKPOINT_DATA) {
  87. /* Right kind of block */
  88. dev->checkpointNextBlock = tags.objectId;
  89. dev->checkpointCurrentBlock = i;
  90. dev->checkpointBlockList[dev->blocksInCheckpoint] = i;
  91. dev->blocksInCheckpoint++;
  92. T(YAFFS_TRACE_CHECKPOINT, (TSTR("found checkpt block %d"TENDSTR), i));
  93. return;
  94. }
  95. }
  96. T(YAFFS_TRACE_CHECKPOINT, (TSTR("found no more checkpt blocks"TENDSTR)));
  97. dev->checkpointNextBlock = -1;
  98. dev->checkpointCurrentBlock = -1;
  99. }
  100. int yaffs2_CheckpointOpen(yaffs_Device *dev, int forWriting)
  101. {
  102. dev->checkpointOpenForWrite = forWriting;
  103. /* Got the functions we need? */
  104. if (!dev->param.writeChunkWithTagsToNAND ||
  105. !dev->param.readChunkWithTagsFromNAND ||
  106. !dev->param.eraseBlockInNAND ||
  107. !dev->param.markNANDBlockBad)
  108. return 0;
  109. if (forWriting && !yaffs2_CheckpointSpaceOk(dev))
  110. return 0;
  111. if (!dev->checkpointBuffer)
  112. dev->checkpointBuffer = YMALLOC_DMA(dev->param.totalBytesPerChunk);
  113. if (!dev->checkpointBuffer)
  114. return 0;
  115. dev->checkpointPageSequence = 0;
  116. dev->checkpointByteCount = 0;
  117. dev->checkpointSum = 0;
  118. dev->checkpointXor = 0;
  119. dev->checkpointCurrentBlock = -1;
  120. dev->checkpointCurrentChunk = -1;
  121. dev->checkpointNextBlock = dev->internalStartBlock;
  122. /* Erase all the blocks in the checkpoint area */
  123. if (forWriting) {
  124. memset(dev->checkpointBuffer, 0, dev->nDataBytesPerChunk);
  125. dev->checkpointByteOffset = 0;
  126. return yaffs2_CheckpointErase(dev);
  127. } else {
  128. int i;
  129. /* Set to a value that will kick off a read */
  130. dev->checkpointByteOffset = dev->nDataBytesPerChunk;
  131. /* A checkpoint block list of 1 checkpoint block per 16 block is (hopefully)
  132. * going to be way more than we need */
  133. dev->blocksInCheckpoint = 0;
  134. dev->checkpointMaxBlocks = (dev->internalEndBlock - dev->internalStartBlock)/16 + 2;
  135. dev->checkpointBlockList = YMALLOC(sizeof(int) * dev->checkpointMaxBlocks);
  136. if(!dev->checkpointBlockList)
  137. return 0;
  138. for (i = 0; i < dev->checkpointMaxBlocks; i++)
  139. dev->checkpointBlockList[i] = -1;
  140. }
  141. return 1;
  142. }
  143. int yaffs2_GetCheckpointSum(yaffs_Device *dev, __u32 *sum)
  144. {
  145. __u32 compositeSum;
  146. compositeSum = (dev->checkpointSum << 8) | (dev->checkpointXor & 0xFF);
  147. *sum = compositeSum;
  148. return 1;
  149. }
  150. static int yaffs2_CheckpointFlushBuffer(yaffs_Device *dev)
  151. {
  152. int chunk;
  153. int realignedChunk;
  154. yaffs_ExtendedTags tags;
  155. if (dev->checkpointCurrentBlock < 0) {
  156. yaffs2_CheckpointFindNextErasedBlock(dev);
  157. dev->checkpointCurrentChunk = 0;
  158. }
  159. if (dev->checkpointCurrentBlock < 0)
  160. return 0;
  161. tags.chunkDeleted = 0;
  162. tags.objectId = dev->checkpointNextBlock; /* Hint to next place to look */
  163. tags.chunkId = dev->checkpointPageSequence + 1;
  164. tags.sequenceNumber = YAFFS_SEQUENCE_CHECKPOINT_DATA;
  165. tags.byteCount = dev->nDataBytesPerChunk;
  166. if (dev->checkpointCurrentChunk == 0) {
  167. /* First chunk we write for the block? Set block state to
  168. checkpoint */
  169. yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, dev->checkpointCurrentBlock);
  170. bi->blockState = YAFFS_BLOCK_STATE_CHECKPOINT;
  171. dev->blocksInCheckpoint++;
  172. }
  173. chunk = dev->checkpointCurrentBlock * dev->param.nChunksPerBlock + dev->checkpointCurrentChunk;
  174. T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint wite buffer nand %d(%d:%d) objid %d chId %d" TENDSTR),
  175. chunk, dev->checkpointCurrentBlock, dev->checkpointCurrentChunk, tags.objectId, tags.chunkId));
  176. realignedChunk = chunk - dev->chunkOffset;
  177. dev->nPageWrites++;
  178. dev->param.writeChunkWithTagsToNAND(dev, realignedChunk,
  179. dev->checkpointBuffer, &tags);
  180. dev->checkpointByteOffset = 0;
  181. dev->checkpointPageSequence++;
  182. dev->checkpointCurrentChunk++;
  183. if (dev->checkpointCurrentChunk >= dev->param.nChunksPerBlock) {
  184. dev->checkpointCurrentChunk = 0;
  185. dev->checkpointCurrentBlock = -1;
  186. }
  187. memset(dev->checkpointBuffer, 0, dev->nDataBytesPerChunk);
  188. return 1;
  189. }
  190. int yaffs2_CheckpointWrite(yaffs_Device *dev, const void *data, int nBytes)
  191. {
  192. int i = 0;
  193. int ok = 1;
  194. __u8 * dataBytes = (__u8 *)data;
  195. if (!dev->checkpointBuffer)
  196. return 0;
  197. if (!dev->checkpointOpenForWrite)
  198. return -1;
  199. while (i < nBytes && ok) {
  200. dev->checkpointBuffer[dev->checkpointByteOffset] = *dataBytes;
  201. dev->checkpointSum += *dataBytes;
  202. dev->checkpointXor ^= *dataBytes;
  203. dev->checkpointByteOffset++;
  204. i++;
  205. dataBytes++;
  206. dev->checkpointByteCount++;
  207. if (dev->checkpointByteOffset < 0 ||
  208. dev->checkpointByteOffset >= dev->nDataBytesPerChunk)
  209. ok = yaffs2_CheckpointFlushBuffer(dev);
  210. }
  211. return i;
  212. }
  213. int yaffs2_CheckpointRead(yaffs_Device *dev, void *data, int nBytes)
  214. {
  215. int i = 0;
  216. int ok = 1;
  217. yaffs_ExtendedTags tags;
  218. int chunk;
  219. int realignedChunk;
  220. __u8 *dataBytes = (__u8 *)data;
  221. if (!dev->checkpointBuffer)
  222. return 0;
  223. if (dev->checkpointOpenForWrite)
  224. return -1;
  225. while (i < nBytes && ok) {
  226. if (dev->checkpointByteOffset < 0 ||
  227. dev->checkpointByteOffset >= dev->nDataBytesPerChunk) {
  228. if (dev->checkpointCurrentBlock < 0) {
  229. yaffs2_CheckpointFindNextCheckpointBlock(dev);
  230. dev->checkpointCurrentChunk = 0;
  231. }
  232. if (dev->checkpointCurrentBlock < 0)
  233. ok = 0;
  234. else {
  235. chunk = dev->checkpointCurrentBlock *
  236. dev->param.nChunksPerBlock +
  237. dev->checkpointCurrentChunk;
  238. realignedChunk = chunk - dev->chunkOffset;
  239. dev->nPageReads++;
  240. /* read in the next chunk */
  241. /* printf("read checkpoint page %d\n",dev->checkpointPage); */
  242. dev->param.readChunkWithTagsFromNAND(dev,
  243. realignedChunk,
  244. dev->checkpointBuffer,
  245. &tags);
  246. if (tags.chunkId != (dev->checkpointPageSequence + 1) ||
  247. tags.eccResult > YAFFS_ECC_RESULT_FIXED ||
  248. tags.sequenceNumber != YAFFS_SEQUENCE_CHECKPOINT_DATA)
  249. ok = 0;
  250. dev->checkpointByteOffset = 0;
  251. dev->checkpointPageSequence++;
  252. dev->checkpointCurrentChunk++;
  253. if (dev->checkpointCurrentChunk >= dev->param.nChunksPerBlock)
  254. dev->checkpointCurrentBlock = -1;
  255. }
  256. }
  257. if (ok) {
  258. *dataBytes = dev->checkpointBuffer[dev->checkpointByteOffset];
  259. dev->checkpointSum += *dataBytes;
  260. dev->checkpointXor ^= *dataBytes;
  261. dev->checkpointByteOffset++;
  262. i++;
  263. dataBytes++;
  264. dev->checkpointByteCount++;
  265. }
  266. }
  267. return i;
  268. }
  269. int yaffs2_CheckpointClose(yaffs_Device *dev)
  270. {
  271. if (dev->checkpointOpenForWrite) {
  272. if (dev->checkpointByteOffset != 0)
  273. yaffs2_CheckpointFlushBuffer(dev);
  274. } else if(dev->checkpointBlockList){
  275. int i;
  276. for (i = 0; i < dev->blocksInCheckpoint && dev->checkpointBlockList[i] >= 0; i++) {
  277. int blk = dev->checkpointBlockList[i];
  278. yaffs_BlockInfo *bi = NULL;
  279. if( dev->internalStartBlock <= blk && blk <= dev->internalEndBlock)
  280. bi = yaffs_GetBlockInfo(dev, blk);
  281. if (bi && bi->blockState == YAFFS_BLOCK_STATE_EMPTY)
  282. bi->blockState = YAFFS_BLOCK_STATE_CHECKPOINT;
  283. else {
  284. /* Todo this looks odd... */
  285. }
  286. }
  287. YFREE(dev->checkpointBlockList);
  288. dev->checkpointBlockList = NULL;
  289. }
  290. dev->nFreeChunks -= dev->blocksInCheckpoint * dev->param.nChunksPerBlock;
  291. dev->nErasedBlocks -= dev->blocksInCheckpoint;
  292. T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint byte count %d" TENDSTR),
  293. dev->checkpointByteCount));
  294. if (dev->checkpointBuffer) {
  295. /* free the buffer */
  296. YFREE(dev->checkpointBuffer);
  297. dev->checkpointBuffer = NULL;
  298. return 1;
  299. } else
  300. return 0;
  301. }
  302. int yaffs2_CheckpointInvalidateStream(yaffs_Device *dev)
  303. {
  304. /* Erase the checkpoint data */
  305. T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint invalidate of %d blocks"TENDSTR),
  306. dev->blocksInCheckpoint));
  307. return yaffs2_CheckpointErase(dev);
  308. }