--- /dev/null
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2007 Aleph One Ltd.
+ * for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_guts.h"
+#include "yaffs_tagscompat.h"
+#include "yaffs_ecc.h"
+
+static void yaffs_HandleReadDataError(yaffs_Device * dev, int chunkInNAND);
+#ifdef NOTYET
+static void yaffs_CheckWrittenBlock(yaffs_Device * dev, int chunkInNAND);
+static void yaffs_HandleWriteChunkOk(yaffs_Device * dev, int chunkInNAND,
+ const __u8 * data,
+ const yaffs_Spare * spare);
+static void yaffs_HandleUpdateChunk(yaffs_Device * dev, int chunkInNAND,
+ const yaffs_Spare * spare);
+static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND);
+#endif
+
+static const char yaffs_countBitsTable[256] = {
+ 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4,
+ 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+ 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+ 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+ 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+ 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+ 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+ 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+ 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+ 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+ 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+ 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+ 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+ 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+ 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+ 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8
+};
+
+int yaffs_CountBits(__u8 x)
+{
+ int retVal;
+ retVal = yaffs_countBitsTable[x];
+ return retVal;
+}
+
+/********** Tags ECC calculations *********/
+
+void yaffs_CalcECC(const __u8 * data, yaffs_Spare * spare)
+{
+ yaffs_ECCCalculate(data, spare->ecc1);
+ yaffs_ECCCalculate(&data[256], spare->ecc2);
+}
+
+void yaffs_CalcTagsECC(yaffs_Tags * tags)
+{
+ /* Calculate an ecc */
+
+ unsigned char *b = ((yaffs_TagsUnion *) tags)->asBytes;
+ unsigned i, j;
+ unsigned ecc = 0;
+ unsigned bit = 0;
+
+ tags->ecc = 0;
+
+ for (i = 0; i < 8; i++) {
+ for (j = 1; j & 0xff; j <<= 1) {
+ bit++;
+ if (b[i] & j) {
+ ecc ^= bit;
+ }
+ }
+ }
+
+ tags->ecc = ecc;
+
+}
+
+int yaffs_CheckECCOnTags(yaffs_Tags * tags)
+{
+ unsigned ecc = tags->ecc;
+
+ yaffs_CalcTagsECC(tags);
+
+ ecc ^= tags->ecc;
+
+ if (ecc && ecc <= 64) {
+ /* TODO: Handle the failure better. Retire? */
+ unsigned char *b = ((yaffs_TagsUnion *) tags)->asBytes;
+
+ ecc--;
+
+ b[ecc / 8] ^= (1 << (ecc & 7));
+
+ /* Now recvalc the ecc */
+ yaffs_CalcTagsECC(tags);
+
+ return 1; /* recovered error */
+ } else if (ecc) {
+ /* Wierd ecc failure value */
+ /* TODO Need to do somethiong here */
+ return -1; /* unrecovered error */
+ }
+
+ return 0;
+}
+
+/********** Tags **********/
+
+static void yaffs_LoadTagsIntoSpare(yaffs_Spare * sparePtr,
+ yaffs_Tags * tagsPtr)
+{
+ yaffs_TagsUnion *tu = (yaffs_TagsUnion *) tagsPtr;
+
+ yaffs_CalcTagsECC(tagsPtr);
+
+ sparePtr->tagByte0 = tu->asBytes[0];
+ sparePtr->tagByte1 = tu->asBytes[1];
+ sparePtr->tagByte2 = tu->asBytes[2];
+ sparePtr->tagByte3 = tu->asBytes[3];
+ sparePtr->tagByte4 = tu->asBytes[4];
+ sparePtr->tagByte5 = tu->asBytes[5];
+ sparePtr->tagByte6 = tu->asBytes[6];
+ sparePtr->tagByte7 = tu->asBytes[7];
+}
+
+static void yaffs_GetTagsFromSpare(yaffs_Device * dev, yaffs_Spare * sparePtr,
+ yaffs_Tags * tagsPtr)
+{
+ yaffs_TagsUnion *tu = (yaffs_TagsUnion *) tagsPtr;
+ int result;
+
+ tu->asBytes[0] = sparePtr->tagByte0;
+ tu->asBytes[1] = sparePtr->tagByte1;
+ tu->asBytes[2] = sparePtr->tagByte2;
+ tu->asBytes[3] = sparePtr->tagByte3;
+ tu->asBytes[4] = sparePtr->tagByte4;
+ tu->asBytes[5] = sparePtr->tagByte5;
+ tu->asBytes[6] = sparePtr->tagByte6;
+ tu->asBytes[7] = sparePtr->tagByte7;
+
+ result = yaffs_CheckECCOnTags(tagsPtr);
+ if (result > 0) {
+ dev->tagsEccFixed++;
+ } else if (result < 0) {
+ dev->tagsEccUnfixed++;
+ }
+}
+
+static void yaffs_SpareInitialise(yaffs_Spare * spare)
+{
+ memset(spare, 0xFF, sizeof(yaffs_Spare));
+}
+
+static int yaffs_WriteChunkToNAND(struct yaffs_DeviceStruct *dev,
+ int chunkInNAND, const __u8 * data,
+ yaffs_Spare * spare)
+{
+ if (chunkInNAND < dev->startBlock * dev->nChunksPerBlock) {
+ T(YAFFS_TRACE_ERROR,
+ (TSTR("**>> yaffs chunk %d is not valid" TENDSTR),
+ chunkInNAND));
+ return YAFFS_FAIL;
+ }
+
+ dev->nPageWrites++;
+ return dev->writeChunkToNAND(dev, chunkInNAND, data, spare);
+}
+
+static int yaffs_ReadChunkFromNAND(struct yaffs_DeviceStruct *dev,
+ int chunkInNAND,
+ __u8 * data,
+ yaffs_Spare * spare,
+ yaffs_ECCResult * eccResult,
+ int doErrorCorrection)
+{
+ int retVal;
+ yaffs_Spare localSpare;
+
+ dev->nPageReads++;
+
+ if (!spare && data) {
+ /* If we don't have a real spare, then we use a local one. */
+ /* Need this for the calculation of the ecc */
+ spare = &localSpare;
+ }
+
+ if (!dev->useNANDECC) {
+ retVal = dev->readChunkFromNAND(dev, chunkInNAND, data, spare);
+ if (data && doErrorCorrection) {
+ /* Do ECC correction */
+ /* Todo handle any errors */
+ int eccResult1, eccResult2;
+ __u8 calcEcc[3];
+
+ yaffs_ECCCalculate(data, calcEcc);
+ eccResult1 =
+ yaffs_ECCCorrect(data, spare->ecc1, calcEcc);
+ yaffs_ECCCalculate(&data[256], calcEcc);
+ eccResult2 =
+ yaffs_ECCCorrect(&data[256], spare->ecc2, calcEcc);
+
+ if (eccResult1 > 0) {
+ T(YAFFS_TRACE_ERROR,
+ (TSTR
+ ("**>>yaffs ecc error fix performed on chunk %d:0"
+ TENDSTR), chunkInNAND));
+ dev->eccFixed++;
+ } else if (eccResult1 < 0) {
+ T(YAFFS_TRACE_ERROR,
+ (TSTR
+ ("**>>yaffs ecc error unfixed on chunk %d:0"
+ TENDSTR), chunkInNAND));
+ dev->eccUnfixed++;
+ }
+
+ if (eccResult2 > 0) {
+ T(YAFFS_TRACE_ERROR,
+ (TSTR
+ ("**>>yaffs ecc error fix performed on chunk %d:1"
+ TENDSTR), chunkInNAND));
+ dev->eccFixed++;
+ } else if (eccResult2 < 0) {
+ T(YAFFS_TRACE_ERROR,
+ (TSTR
+ ("**>>yaffs ecc error unfixed on chunk %d:1"
+ TENDSTR), chunkInNAND));
+ dev->eccUnfixed++;
+ }
+
+ if (eccResult1 || eccResult2) {
+ /* We had a data problem on this page */
+ yaffs_HandleReadDataError(dev, chunkInNAND);
+ }
+
+ if (eccResult1 < 0 || eccResult2 < 0)
+ *eccResult = YAFFS_ECC_RESULT_UNFIXED;
+ else if (eccResult1 > 0 || eccResult2 > 0)
+ *eccResult = YAFFS_ECC_RESULT_FIXED;
+ else
+ *eccResult = YAFFS_ECC_RESULT_NO_ERROR;
+ }
+ } else {
+ /* Must allocate enough memory for spare+2*sizeof(int) */
+ /* for ecc results from device. */
+ struct yaffs_NANDSpare nspare;
+ retVal =
+ dev->readChunkFromNAND(dev, chunkInNAND, data,
+ (yaffs_Spare *) & nspare);
+ memcpy(spare, &nspare, sizeof(yaffs_Spare));
+ if (data && doErrorCorrection) {
+ if (nspare.eccres1 > 0) {
+ T(YAFFS_TRACE_ERROR,
+ (TSTR
+ ("**>>mtd ecc error fix performed on chunk %d:0"
+ TENDSTR), chunkInNAND));
+ } else if (nspare.eccres1 < 0) {
+ T(YAFFS_TRACE_ERROR,
+ (TSTR
+ ("**>>mtd ecc error unfixed on chunk %d:0"
+ TENDSTR), chunkInNAND));
+ }
+
+ if (nspare.eccres2 > 0) {
+ T(YAFFS_TRACE_ERROR,
+ (TSTR
+ ("**>>mtd ecc error fix performed on chunk %d:1"
+ TENDSTR), chunkInNAND));
+ } else if (nspare.eccres2 < 0) {
+ T(YAFFS_TRACE_ERROR,
+ (TSTR
+ ("**>>mtd ecc error unfixed on chunk %d:1"
+ TENDSTR), chunkInNAND));
+ }
+
+ if (nspare.eccres1 || nspare.eccres2) {
+ /* We had a data problem on this page */
+ yaffs_HandleReadDataError(dev, chunkInNAND);
+ }
+
+ if (nspare.eccres1 < 0 || nspare.eccres2 < 0)
+ *eccResult = YAFFS_ECC_RESULT_UNFIXED;
+ else if (nspare.eccres1 > 0 || nspare.eccres2 > 0)
+ *eccResult = YAFFS_ECC_RESULT_FIXED;
+ else
+ *eccResult = YAFFS_ECC_RESULT_NO_ERROR;
+
+ }
+ }
+ return retVal;
+}
+
+#ifdef NOTYET
+static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
+ int chunkInNAND)
+{
+
+ static int init = 0;
+ static __u8 cmpbuf[YAFFS_BYTES_PER_CHUNK];
+ static __u8 data[YAFFS_BYTES_PER_CHUNK];
+ /* Might as well always allocate the larger size for */
+ /* dev->useNANDECC == true; */
+ static __u8 spare[sizeof(struct yaffs_NANDSpare)];
+
+ dev->readChunkFromNAND(dev, chunkInNAND, data, (yaffs_Spare *) spare);
+
+ if (!init) {
+ memset(cmpbuf, 0xff, YAFFS_BYTES_PER_CHUNK);
+ init = 1;
+ }
+
+ if (memcmp(cmpbuf, data, YAFFS_BYTES_PER_CHUNK))
+ return YAFFS_FAIL;
+ if (memcmp(cmpbuf, spare, 16))
+ return YAFFS_FAIL;
+
+ return YAFFS_OK;
+
+}
+#endif
+
+/*
+ * Functions for robustisizing
+ */
+
+static void yaffs_HandleReadDataError(yaffs_Device * dev, int chunkInNAND)
+{
+ int blockInNAND = chunkInNAND / dev->nChunksPerBlock;
+
+ /* Mark the block for retirement */
+ yaffs_GetBlockInfo(dev, blockInNAND)->needsRetiring = 1;
+ T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
+ (TSTR("**>>Block %d marked for retirement" TENDSTR), blockInNAND));
+
+ /* TODO:
+ * Just do a garbage collection on the affected block
+ * then retire the block
+ * NB recursion
+ */
+}
+
+#ifdef NOTYET
+static void yaffs_CheckWrittenBlock(yaffs_Device * dev, int chunkInNAND)
+{
+}
+
+static void yaffs_HandleWriteChunkOk(yaffs_Device * dev, int chunkInNAND,
+ const __u8 * data,
+ const yaffs_Spare * spare)
+{
+}
+
+static void yaffs_HandleUpdateChunk(yaffs_Device * dev, int chunkInNAND,
+ const yaffs_Spare * spare)
+{
+}
+
+static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND)
+{
+ int blockInNAND = chunkInNAND / dev->nChunksPerBlock;
+
+ /* Mark the block for retirement */
+ yaffs_GetBlockInfo(dev, blockInNAND)->needsRetiring = 1;
+ /* Delete the chunk */
+ yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
+}
+
+static int yaffs_VerifyCompare(const __u8 * d0, const __u8 * d1,
+ const yaffs_Spare * s0, const yaffs_Spare * s1)
+{
+
+ if (memcmp(d0, d1, YAFFS_BYTES_PER_CHUNK) != 0 ||
+ s0->tagByte0 != s1->tagByte0 ||
+ s0->tagByte1 != s1->tagByte1 ||
+ s0->tagByte2 != s1->tagByte2 ||
+ s0->tagByte3 != s1->tagByte3 ||
+ s0->tagByte4 != s1->tagByte4 ||
+ s0->tagByte5 != s1->tagByte5 ||
+ s0->tagByte6 != s1->tagByte6 ||
+ s0->tagByte7 != s1->tagByte7 ||
+ s0->ecc1[0] != s1->ecc1[0] ||
+ s0->ecc1[1] != s1->ecc1[1] ||
+ s0->ecc1[2] != s1->ecc1[2] ||
+ s0->ecc2[0] != s1->ecc2[0] ||
+ s0->ecc2[1] != s1->ecc2[1] || s0->ecc2[2] != s1->ecc2[2]) {
+ return 0;
+ }
+
+ return 1;
+}
+#endif /* NOTYET */
+
+int yaffs_TagsCompatabilityWriteChunkWithTagsToNAND(yaffs_Device * dev,
+ int chunkInNAND,
+ const __u8 * data,
+ const yaffs_ExtendedTags *
+ eTags)
+{
+ yaffs_Spare spare;
+ yaffs_Tags tags;
+
+ yaffs_SpareInitialise(&spare);
+
+ if (eTags->chunkDeleted) {
+ spare.pageStatus = 0;
+ } else {
+ tags.objectId = eTags->objectId;
+ tags.chunkId = eTags->chunkId;
+ tags.byteCount = eTags->byteCount;
+ tags.serialNumber = eTags->serialNumber;
+
+ if (!dev->useNANDECC && data) {
+ yaffs_CalcECC(data, &spare);
+ }
+ yaffs_LoadTagsIntoSpare(&spare, &tags);
+
+ }
+
+ return yaffs_WriteChunkToNAND(dev, chunkInNAND, data, &spare);
+}
+
+int yaffs_TagsCompatabilityReadChunkWithTagsFromNAND(yaffs_Device * dev,
+ int chunkInNAND,
+ __u8 * data,
+ yaffs_ExtendedTags * eTags)
+{
+
+ yaffs_Spare spare;
+ yaffs_Tags tags;
+ yaffs_ECCResult eccResult;
+
+ static yaffs_Spare spareFF;
+ static int init;
+
+ if (!init) {
+ memset(&spareFF, 0xFF, sizeof(spareFF));
+ init = 1;
+ }
+
+ if (yaffs_ReadChunkFromNAND
+ (dev, chunkInNAND, data, &spare, &eccResult, 1)) {
+ /* eTags may be NULL */
+ if (eTags) {
+
+ int deleted =
+ (yaffs_CountBits(spare.pageStatus) < 7) ? 1 : 0;
+
+ eTags->chunkDeleted = deleted;
+ eTags->eccResult = eccResult;
+ eTags->blockBad = 0; /* We're reading it */
+ /* therefore it is not a bad block */
+ eTags->chunkUsed =
+ (memcmp(&spareFF, &spare, sizeof(spareFF)) !=
+ 0) ? 1 : 0;
+
+ if (eTags->chunkUsed) {
+ yaffs_GetTagsFromSpare(dev, &spare, &tags);
+
+ eTags->objectId = tags.objectId;
+ eTags->chunkId = tags.chunkId;
+ eTags->byteCount = tags.byteCount;
+ eTags->serialNumber = tags.serialNumber;
+ }
+ }
+
+ return YAFFS_OK;
+ } else {
+ return YAFFS_FAIL;
+ }
+}
+
+int yaffs_TagsCompatabilityMarkNANDBlockBad(struct yaffs_DeviceStruct *dev,
+ int blockInNAND)
+{
+
+ yaffs_Spare spare;
+
+ memset(&spare, 0xff, sizeof(yaffs_Spare));
+
+ spare.blockStatus = 'Y';
+
+ yaffs_WriteChunkToNAND(dev, blockInNAND * dev->nChunksPerBlock, NULL,
+ &spare);
+ yaffs_WriteChunkToNAND(dev, blockInNAND * dev->nChunksPerBlock + 1,
+ NULL, &spare);
+
+ return YAFFS_OK;
+
+}
+
+int yaffs_TagsCompatabilityQueryNANDBlock(struct yaffs_DeviceStruct *dev,
+ int blockNo, yaffs_BlockState *
+ state,
+ int *sequenceNumber)
+{
+
+ yaffs_Spare spare0, spare1;
+ static yaffs_Spare spareFF;
+ static int init;
+ yaffs_ECCResult dummy;
+
+ if (!init) {
+ memset(&spareFF, 0xFF, sizeof(spareFF));
+ init = 1;
+ }
+
+ *sequenceNumber = 0;
+
+ yaffs_ReadChunkFromNAND(dev, blockNo * dev->nChunksPerBlock, NULL,
+ &spare0, &dummy, 1);
+ yaffs_ReadChunkFromNAND(dev, blockNo * dev->nChunksPerBlock + 1, NULL,
+ &spare1, &dummy, 1);
+
+ if (yaffs_CountBits(spare0.blockStatus & spare1.blockStatus) < 7)
+ *state = YAFFS_BLOCK_STATE_DEAD;
+ else if (memcmp(&spareFF, &spare0, sizeof(spareFF)) == 0)
+ *state = YAFFS_BLOCK_STATE_EMPTY;
+ else
+ *state = YAFFS_BLOCK_STATE_NEEDS_SCANNING;
+
+ return YAFFS_OK;
+}
projects / openwrt / svn-archive / archive.git / blobdiff