2 * YAFFS: Yet another FFS. A NAND-flash specific file system.
3 * yaffs_tagscompat.h: Tags compatability layer to use YAFFS1 formatted NAND.
5 * Copyright (C) 2002 Aleph One Ltd.
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.
13 * $Id: yaffs_tagscompat.c,v 1.2 2005-03-16 04:00:36 charles Exp $
16 #include "yaffs_guts.h"
17 #include "yaffs_tagscompat.h"
18 #include "yaffs_ecc.h"
20 static void yaffs_HandleReadDataError(yaffs_Device *dev,int chunkInNAND);
21 static void yaffs_CheckWrittenBlock(yaffs_Device *dev,int chunkInNAND);
22 static void yaffs_HandleWriteChunkOk(yaffs_Device *dev,int chunkInNAND,const __u8 *data, const yaffs_Spare *spare);
23 static void yaffs_HandleUpdateChunk(yaffs_Device *dev,int chunkInNAND, const yaffs_Spare *spare);
24 static void yaffs_HandleWriteChunkError(yaffs_Device *dev,int chunkInNAND);
28 static const char yaffs_countBitsTable[256] =
30 0,1,1,2,1,2,2,3,1,2,2,3,2,3,3,4,
31 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,
32 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,
33 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
34 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,
35 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
36 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
37 3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
38 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,
39 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
40 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
41 3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
42 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
43 3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
44 3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
45 4,5,5,6,5,6,6,7,5,6,6,7,6,7,7,8
48 static int yaffs_CountBits(__u8 x)
51 retVal = yaffs_countBitsTable[x];
56 /////////////// Tags ECC calculations ///////////////////
58 void yaffs_CalcECC(const __u8 *data, yaffs_Spare *spare)
60 yaffs_ECCCalculate(data , spare->ecc1);
61 yaffs_ECCCalculate(&data[256] , spare->ecc2);
64 void yaffs_CalcTagsECC(yaffs_Tags *tags)
68 unsigned char *b = ((yaffs_TagsUnion *)tags)->asBytes;
75 for(i = 0; i < 8; i++)
77 for(j = 1; j &0xff; j<<=1)
92 int yaffs_CheckECCOnTags(yaffs_Tags *tags)
94 unsigned ecc = tags->ecc;
96 yaffs_CalcTagsECC(tags);
102 // TODO: Handle the failure better. Retire?
103 unsigned char *b = ((yaffs_TagsUnion *)tags)->asBytes;
107 b[ecc / 8] ^= (1 << (ecc & 7));
109 // Now recvalc the ecc
110 yaffs_CalcTagsECC(tags);
112 return 1; // recovered error
116 // Wierd ecc failure value
117 // TODO Need to do somethiong here
118 return -1; //unrecovered error
124 //////////////////////////// Tags ///////////////////////////////////////
126 static void yaffs_LoadTagsIntoSpare(yaffs_Spare *sparePtr, yaffs_Tags *tagsPtr)
128 yaffs_TagsUnion *tu = (yaffs_TagsUnion *)tagsPtr;
130 yaffs_CalcTagsECC(tagsPtr);
132 sparePtr->tagByte0 = tu->asBytes[0];
133 sparePtr->tagByte1 = tu->asBytes[1];
134 sparePtr->tagByte2 = tu->asBytes[2];
135 sparePtr->tagByte3 = tu->asBytes[3];
136 sparePtr->tagByte4 = tu->asBytes[4];
137 sparePtr->tagByte5 = tu->asBytes[5];
138 sparePtr->tagByte6 = tu->asBytes[6];
139 sparePtr->tagByte7 = tu->asBytes[7];
142 static void yaffs_GetTagsFromSpare(yaffs_Device *dev, yaffs_Spare *sparePtr,yaffs_Tags *tagsPtr)
144 yaffs_TagsUnion *tu = (yaffs_TagsUnion *)tagsPtr;
147 tu->asBytes[0]= sparePtr->tagByte0;
148 tu->asBytes[1]= sparePtr->tagByte1;
149 tu->asBytes[2]= sparePtr->tagByte2;
150 tu->asBytes[3]= sparePtr->tagByte3;
151 tu->asBytes[4]= sparePtr->tagByte4;
152 tu->asBytes[5]= sparePtr->tagByte5;
153 tu->asBytes[6]= sparePtr->tagByte6;
154 tu->asBytes[7]= sparePtr->tagByte7;
156 result = yaffs_CheckECCOnTags(tagsPtr);
163 dev->tagsEccUnfixed++;
167 static void yaffs_SpareInitialise(yaffs_Spare *spare)
169 memset(spare,0xFF,sizeof(yaffs_Spare));
175 static int yaffs_WriteChunkToNAND(struct yaffs_DeviceStruct *dev,int chunkInNAND, const __u8 *data, yaffs_Spare *spare)
177 if(chunkInNAND < dev->startBlock * dev->nChunksPerBlock)
179 T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs chunk %d is not valid" TENDSTR),chunkInNAND));
184 return dev->writeChunkToNAND(dev,chunkInNAND,data,spare);
189 static int yaffs_ReadChunkFromNAND(struct yaffs_DeviceStruct *dev,
193 yaffs_ECCResult *eccResult,
194 int doErrorCorrection)
197 yaffs_Spare localSpare;
206 // If we don't have a real spare, then we use a local one.
207 // Need this for the calculation of the ecc
214 retVal = dev->readChunkFromNAND(dev,chunkInNAND,data,spare);
215 if(data && doErrorCorrection)
218 //Todo handle any errors
219 int eccResult1,eccResult2;
222 yaffs_ECCCalculate(data,calcEcc);
223 eccResult1 = yaffs_ECCCorrect (data,spare->ecc1, calcEcc);
224 yaffs_ECCCalculate(&data[256],calcEcc);
225 eccResult2 = yaffs_ECCCorrect(&data[256],spare->ecc2, calcEcc);
229 T(YAFFS_TRACE_ERROR, (TSTR("**>>ecc error fix performed on chunk %d:0" TENDSTR),chunkInNAND));
232 else if(eccResult1<0)
234 T(YAFFS_TRACE_ERROR,(TSTR("**>>ecc error unfixed on chunk %d:0" TENDSTR),chunkInNAND));
240 T(YAFFS_TRACE_ERROR,(TSTR("**>>ecc error fix performed on chunk %d:1" TENDSTR),chunkInNAND));
243 else if(eccResult2<0)
245 T(YAFFS_TRACE_ERROR,(TSTR("**>>ecc error unfixed on chunk %d:1" TENDSTR),chunkInNAND));
249 if(eccResult1 || eccResult2)
251 // Hoosterman, we had a data problem on this page
252 yaffs_HandleReadDataError(dev,chunkInNAND);
255 if(eccResult1 < 0 || eccResult2 < 0)
256 *eccResult = YAFFS_ECC_RESULT_UNFIXED;
257 else if(eccResult1 > 0 || eccResult2 > 0)
258 *eccResult = YAFFS_ECC_RESULT_FIXED;
260 *eccResult = YAFFS_ECC_RESULT_NO_ERROR;
265 // Must allocate enough memory for spare+2*sizeof(int) for ecc results from device.
266 struct yaffs_NANDSpare nspare;
267 retVal = dev->readChunkFromNAND(dev,chunkInNAND,data,(yaffs_Spare*)&nspare);
268 memcpy (spare, &nspare, sizeof(yaffs_Spare));
269 if(data && doErrorCorrection)
273 T(YAFFS_TRACE_ERROR,(TSTR("**>>ecc error fix performed on chunk %d:0" TENDSTR),chunkInNAND));
275 else if(nspare.eccres1<0)
277 T(YAFFS_TRACE_ERROR,(TSTR("**>>ecc error unfixed on chunk %d:0" TENDSTR),chunkInNAND));
282 T(YAFFS_TRACE_ERROR,(TSTR("**>>ecc error fix performed on chunk %d:1" TENDSTR),chunkInNAND));
284 else if(nspare.eccres2<0)
286 T(YAFFS_TRACE_ERROR,(TSTR("**>>ecc error unfixed on chunk %d:1" TENDSTR),chunkInNAND));
289 if(nspare.eccres1 || nspare.eccres2)
291 // Hoosterman, we had a data problem on this page
292 yaffs_HandleReadDataError(dev,chunkInNAND);
295 if(nspare.eccres1 < 0 || nspare.eccres2 < 0)
296 *eccResult = YAFFS_ECC_RESULT_UNFIXED;
297 else if(nspare.eccres1 > 0 || nspare.eccres2 > 0)
298 *eccResult = YAFFS_ECC_RESULT_FIXED;
300 *eccResult = YAFFS_ECC_RESULT_NO_ERROR;
310 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,int chunkInNAND)
314 static __u8 cmpbuf[YAFFS_BYTES_PER_CHUNK];
315 static __u8 data[YAFFS_BYTES_PER_CHUNK];
316 // Might as well always allocate the larger size for dev->useNANDECC == true;
317 static __u8 spare[sizeof(struct yaffs_NANDSpare)];
319 dev->readChunkFromNAND(dev,chunkInNAND,data,(yaffs_Spare *)spare);
323 memset(cmpbuf,0xff,YAFFS_BYTES_PER_CHUNK);
327 if(memcmp(cmpbuf,data,YAFFS_BYTES_PER_CHUNK)) return YAFFS_FAIL;
328 if(memcmp(cmpbuf,spare,16)) return YAFFS_FAIL;
337 int yaffs_EraseBlockInNAND(struct yaffs_DeviceStruct *dev,int blockInNAND)
339 dev->nBlockErasures++;
340 return dev->eraseBlockInNAND(dev,blockInNAND);
343 int yaffs_InitialiseNAND(struct yaffs_DeviceStruct *dev)
345 return dev->initialiseNAND(dev);
351 static int yaffs_WriteNewChunkToNAND(struct yaffs_DeviceStruct *dev, const __u8 *data, yaffs_Spare *spare,int useReserve)
358 unsigned char rbData[YAFFS_BYTES_PER_CHUNK];
362 chunk = yaffs_AllocateChunk(dev,useReserve);
367 // First check this chunk is erased...
368 #ifndef CONFIG_YAFFS_DISABLE_CHUNK_ERASED_CHECK
369 writeOk = yaffs_CheckChunkErased(dev,chunk);
373 T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs chunk %d was not erased" TENDSTR),chunk));
377 writeOk = yaffs_WriteChunkToNAND(dev,chunk,data,spare);
383 // If verify fails, then delete this chunk and try again
384 // To verify we compare everything except the block and
385 // page status bytes.
386 // NB We check a raw read without ECC correction applied
387 yaffs_ReadChunkFromNAND(dev,chunk,rbData,&rbSpare,0);
389 #ifndef CONFIG_YAFFS_DISABLE_WRITE_VERIFY
390 if(!yaffs_VerifyCompare(data,rbData,spare,&rbSpare))
393 T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs write verify failed on chunk %d" TENDSTR), chunk));
402 // Copy the data into the write buffer.
403 // NB We do this at the end to prevent duplicates in the case of a write error.
405 yaffs_HandleWriteChunkOk(dev,chunk,data,spare);
409 yaffs_HandleWriteChunkError(dev,chunk);
413 } while(chunk >= 0 && ! writeOk);
417 T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs write required %d attempts" TENDSTR),attempts));
418 dev->nRetriedWrites+= (attempts - 1);
427 // Functions for robustisizing
432 static void yaffs_RetireBlock(yaffs_Device *dev,int blockInNAND)
434 // Ding the blockStatus in the first two pages of the block.
438 memset(&spare, 0xff,sizeof(yaffs_Spare));
440 spare.blockStatus = 0;
442 // TODO change this retirement marking for other NAND types
443 yaffs_WriteChunkToNAND(dev, blockInNAND * dev->nChunksPerBlock, NULL , &spare);
444 yaffs_WriteChunkToNAND(dev, blockInNAND * dev->nChunksPerBlock + 1, NULL , &spare);
446 yaffs_GetBlockInfo(dev,blockInNAND)->blockState = YAFFS_BLOCK_STATE_DEAD;
447 dev->nRetiredBlocks++;
453 static int yaffs_RewriteBufferedBlock(yaffs_Device *dev)
455 dev->doingBufferedBlockRewrite = 1;
457 // Remove erased chunks
458 // Rewrite existing chunks to a new block
459 // Set current write block to the new block
461 dev->doingBufferedBlockRewrite = 0;
468 static void yaffs_HandleReadDataError(yaffs_Device *dev,int chunkInNAND)
470 int blockInNAND = chunkInNAND/dev->nChunksPerBlock;
472 // Mark the block for retirement
473 yaffs_GetBlockInfo(dev,blockInNAND)->needsRetiring = 1;
474 T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,(TSTR("**>>Block %d marked for retirement" TENDSTR),blockInNAND));
478 // Just do a garbage collection on the affected block then retire the block
483 static void yaffs_CheckWrittenBlock(yaffs_Device *dev,int chunkInNAND)
487 static void yaffs_HandleWriteChunkOk(yaffs_Device *dev,int chunkInNAND,const __u8 *data, const yaffs_Spare *spare)
491 static void yaffs_HandleUpdateChunk(yaffs_Device *dev,int chunkInNAND, const yaffs_Spare *spare)
495 static void yaffs_HandleWriteChunkError(yaffs_Device *dev,int chunkInNAND)
497 int blockInNAND = chunkInNAND/dev->nChunksPerBlock;
499 // Mark the block for retirement
500 yaffs_GetBlockInfo(dev,blockInNAND)->needsRetiring = 1;
502 yaffs_DeleteChunk(dev,chunkInNAND,1,__LINE__);
508 static int yaffs_VerifyCompare(const __u8 *d0, const __u8 * d1, const yaffs_Spare *s0, const yaffs_Spare *s1)
512 if( memcmp(d0,d1,YAFFS_BYTES_PER_CHUNK) != 0 ||
513 s0->tagByte0 != s1->tagByte0 ||
514 s0->tagByte1 != s1->tagByte1 ||
515 s0->tagByte2 != s1->tagByte2 ||
516 s0->tagByte3 != s1->tagByte3 ||
517 s0->tagByte4 != s1->tagByte4 ||
518 s0->tagByte5 != s1->tagByte5 ||
519 s0->tagByte6 != s1->tagByte6 ||
520 s0->tagByte7 != s1->tagByte7 ||
521 s0->ecc1[0] != s1->ecc1[0] ||
522 s0->ecc1[1] != s1->ecc1[1] ||
523 s0->ecc1[2] != s1->ecc1[2] ||
524 s0->ecc2[0] != s1->ecc2[0] ||
525 s0->ecc2[1] != s1->ecc2[1] ||
526 s0->ecc2[2] != s1->ecc2[2] )
538 unsigned validMarker0;
539 unsigned chunkUsed; // Status of the chunk: used or unused
540 unsigned objectId; // If 0 then this is not part of an object (unused)
541 unsigned chunkId; // If 0 then this is a header
542 unsigned byteCount; // Only valid for data chunks
543 // The following stuff only has meaning when we read
544 yaffs_ECCResult eccResult; // Only valid when we read.
545 unsigned blockBad; // Only valid on reading
548 unsigned chunkDeleted; // The chunk is marked deleted
549 unsigned serialNumber; // Yaffs1 2-bit serial number
552 unsigned sequenceNumber; // The sequence number of this block
554 unsigned validMarker1;
556 } yaffs_ExtendedTags;
562 unsigned serialNumber:2;
563 unsigned byteCount:10;
564 unsigned objectId:18;
566 unsigned unusedStuff:2;
572 int yaffs_TagsCompatabilityWriteChunkWithTagsToNAND(yaffs_Device *dev,int chunkInNAND,const __u8 *data, const yaffs_ExtendedTags *eTags)
577 yaffs_SpareInitialise(&spare);
579 if(eTags->chunkDeleted)
581 spare.pageStatus = 0;
585 tags.objectId = eTags->objectId;
586 tags.chunkId = eTags->chunkId;
587 tags.byteCount = eTags->byteCount;
588 tags.serialNumber = eTags->serialNumber;
591 if (!dev->useNANDECC && data)
593 yaffs_CalcECC(data,&spare);
597 yaffs_LoadTagsIntoSpare(&spare,&tags);
601 return yaffs_WriteChunkToNAND(dev,chunkInNAND,data,&spare);
605 int yaffs_TagsCompatabilityReadChunkWithTagsFromNAND(yaffs_Device *dev,int chunkInNAND, __u8 *data, yaffs_ExtendedTags *eTags)
610 yaffs_ECCResult eccResult;
613 static yaffs_Spare spareFF;
618 memset(&spareFF,0xFF,sizeof(spareFF));
622 if(yaffs_ReadChunkFromNAND(dev,chunkInNAND,data,&spare,&eccResult,1))
624 // added NCB - eTags may be NULL
627 int deleted = (yaffs_CountBits(spare.pageStatus) < 7) ? 1 : 0;
629 yaffs_GetTagsFromSpare(dev,&spare,&tags);
631 eTags->chunkDeleted = deleted;
632 eTags->objectId = tags.objectId;
633 eTags->chunkId = tags.chunkId;
634 eTags->byteCount = tags.byteCount;
635 eTags->serialNumber = tags.serialNumber;
636 eTags->eccResult = eccResult;
637 eTags->blockBad = 0; // We're reading it therefore it is not a bad block
639 // NCB added 18/2/2005
640 eTags->chunkUsed = (memcmp(&spareFF,&spare,sizeof(spareFF)) != 0) ? 1:0;
651 int yaffs_TagsCompatabilityMarkNANDBlockBad(struct yaffs_DeviceStruct *dev, int blockInNAND)
656 memset(&spare, 0xff,sizeof(yaffs_Spare));
658 spare.blockStatus = 0;
660 yaffs_WriteChunkToNAND(dev, blockInNAND * dev->nChunksPerBlock, NULL , &spare);
661 yaffs_WriteChunkToNAND(dev, blockInNAND * dev->nChunksPerBlock + 1, NULL , &spare);
668 int yaffs_TagsCompatabilityQueryNANDBlock(struct yaffs_DeviceStruct *dev, int blockNo, yaffs_BlockState *state, int *sequenceNumber)
671 yaffs_Spare spare0,spare1;
672 static yaffs_Spare spareFF;
674 yaffs_ECCResult dummy;
678 memset(&spareFF,0xFF,sizeof(spareFF));
684 yaffs_ReadChunkFromNAND(dev,blockNo * dev->nChunksPerBlock,NULL,&spare0,&dummy,1);
685 yaffs_ReadChunkFromNAND(dev,blockNo * dev->nChunksPerBlock + 1,NULL,&spare1,&dummy,1);
687 if(yaffs_CountBits(spare0.blockStatus & spare1.blockStatus) < 7)
688 *state = YAFFS_BLOCK_STATE_DEAD;
689 else if(memcmp(&spareFF,&spare0,sizeof(spareFF)) == 0)
690 *state = YAFFS_BLOCK_STATE_EMPTY;
692 *state = YAFFS_BLOCK_STATE_NEEDS_SCANNING;