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 /* XXX U-BOOT XXX */
15 #include <common.h>
16
17 #include "yaffs_guts.h"
18 #include "yaffs_tagscompat.h"
19 #include "yaffs_ecc.h"
20
21 static void yaffs_HandleReadDataError(yaffs_Device * dev, int chunkInNAND);
22 #ifdef NOTYET
23 static void yaffs_CheckWrittenBlock(yaffs_Device * dev, int chunkInNAND);
24 static void yaffs_HandleWriteChunkOk(yaffs_Device * dev, int chunkInNAND,
25 const __u8 * data,
26 const yaffs_Spare * spare);
27 static void yaffs_HandleUpdateChunk(yaffs_Device * dev, int chunkInNAND,
28 const yaffs_Spare * spare);
29 static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND);
30 #endif
31
32 static const char yaffs_countBitsTable[256] = {
33 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4,
34 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
35 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
36 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
37 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
38 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
39 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
40 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
41 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
42 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
43 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
44 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
45 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
46 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
47 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
48 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8
49 };
50
yaffs_CountBits(__u8 x)51 int yaffs_CountBits(__u8 x)
52 {
53 int retVal;
54 retVal = yaffs_countBitsTable[x];
55 return retVal;
56 }
57
58 /********** Tags ECC calculations *********/
59
yaffs_CalcECC(const __u8 * data,yaffs_Spare * spare)60 void yaffs_CalcECC(const __u8 * data, yaffs_Spare * spare)
61 {
62 yaffs_ECCCalculate(data, spare->ecc1);
63 yaffs_ECCCalculate(&data[256], spare->ecc2);
64 }
65
yaffs_CalcTagsECC(yaffs_Tags * tags)66 void yaffs_CalcTagsECC(yaffs_Tags * tags)
67 {
68 /* Calculate an ecc */
69
70 unsigned char *b = ((yaffs_TagsUnion *) tags)->asBytes;
71 unsigned i, j;
72 unsigned ecc = 0;
73 unsigned bit = 0;
74
75 tags->ecc = 0;
76
77 for (i = 0; i < 8; i++) {
78 for (j = 1; j & 0xff; j <<= 1) {
79 bit++;
80 if (b[i] & j) {
81 ecc ^= bit;
82 }
83 }
84 }
85
86 tags->ecc = ecc;
87
88 }
89
yaffs_CheckECCOnTags(yaffs_Tags * tags)90 int yaffs_CheckECCOnTags(yaffs_Tags * tags)
91 {
92 unsigned ecc = tags->ecc;
93
94 yaffs_CalcTagsECC(tags);
95
96 ecc ^= tags->ecc;
97
98 if (ecc && ecc <= 64) {
99 /* TODO: Handle the failure better. Retire? */
100 unsigned char *b = ((yaffs_TagsUnion *) tags)->asBytes;
101
102 ecc--;
103
104 b[ecc / 8] ^= (1 << (ecc & 7));
105
106 /* Now recvalc the ecc */
107 yaffs_CalcTagsECC(tags);
108
109 return 1; /* recovered error */
110 } else if (ecc) {
111 /* Wierd ecc failure value */
112 /* TODO Need to do somethiong here */
113 return -1; /* unrecovered error */
114 }
115
116 return 0;
117 }
118
119 /********** Tags **********/
120
yaffs_LoadTagsIntoSpare(yaffs_Spare * sparePtr,yaffs_Tags * tagsPtr)121 static void yaffs_LoadTagsIntoSpare(yaffs_Spare * sparePtr,
122 yaffs_Tags * tagsPtr)
123 {
124 yaffs_TagsUnion *tu = (yaffs_TagsUnion *) tagsPtr;
125
126 yaffs_CalcTagsECC(tagsPtr);
127
128 sparePtr->tagByte0 = tu->asBytes[0];
129 sparePtr->tagByte1 = tu->asBytes[1];
130 sparePtr->tagByte2 = tu->asBytes[2];
131 sparePtr->tagByte3 = tu->asBytes[3];
132 sparePtr->tagByte4 = tu->asBytes[4];
133 sparePtr->tagByte5 = tu->asBytes[5];
134 sparePtr->tagByte6 = tu->asBytes[6];
135 sparePtr->tagByte7 = tu->asBytes[7];
136 }
137
yaffs_GetTagsFromSpare(yaffs_Device * dev,yaffs_Spare * sparePtr,yaffs_Tags * tagsPtr)138 static void yaffs_GetTagsFromSpare(yaffs_Device * dev, yaffs_Spare * sparePtr,
139 yaffs_Tags * tagsPtr)
140 {
141 yaffs_TagsUnion *tu = (yaffs_TagsUnion *) tagsPtr;
142 int result;
143
144 tu->asBytes[0] = sparePtr->tagByte0;
145 tu->asBytes[1] = sparePtr->tagByte1;
146 tu->asBytes[2] = sparePtr->tagByte2;
147 tu->asBytes[3] = sparePtr->tagByte3;
148 tu->asBytes[4] = sparePtr->tagByte4;
149 tu->asBytes[5] = sparePtr->tagByte5;
150 tu->asBytes[6] = sparePtr->tagByte6;
151 tu->asBytes[7] = sparePtr->tagByte7;
152
153 result = yaffs_CheckECCOnTags(tagsPtr);
154 if (result > 0) {
155 dev->tagsEccFixed++;
156 } else if (result < 0) {
157 dev->tagsEccUnfixed++;
158 }
159 }
160
yaffs_SpareInitialise(yaffs_Spare * spare)161 static void yaffs_SpareInitialise(yaffs_Spare * spare)
162 {
163 memset(spare, 0xFF, sizeof(yaffs_Spare));
164 }
165
yaffs_WriteChunkToNAND(struct yaffs_DeviceStruct * dev,int chunkInNAND,const __u8 * data,yaffs_Spare * spare)166 static int yaffs_WriteChunkToNAND(struct yaffs_DeviceStruct *dev,
167 int chunkInNAND, const __u8 * data,
168 yaffs_Spare * spare)
169 {
170 if (chunkInNAND < dev->startBlock * dev->nChunksPerBlock) {
171 T(YAFFS_TRACE_ERROR,
172 (TSTR("**>> yaffs chunk %d is not valid" TENDSTR),
173 chunkInNAND));
174 return YAFFS_FAIL;
175 }
176
177 dev->nPageWrites++;
178 return dev->writeChunkToNAND(dev, chunkInNAND, data, spare);
179 }
180
yaffs_ReadChunkFromNAND(struct yaffs_DeviceStruct * dev,int chunkInNAND,__u8 * data,yaffs_Spare * spare,yaffs_ECCResult * eccResult,int doErrorCorrection)181 static int yaffs_ReadChunkFromNAND(struct yaffs_DeviceStruct *dev,
182 int chunkInNAND,
183 __u8 * data,
184 yaffs_Spare * spare,
185 yaffs_ECCResult * eccResult,
186 int doErrorCorrection)
187 {
188 int retVal;
189 yaffs_Spare localSpare;
190
191 dev->nPageReads++;
192
193 if (!spare && data) {
194 /* If we don't have a real spare, then we use a local one. */
195 /* Need this for the calculation of the ecc */
196 spare = &localSpare;
197 }
198
199 if (!dev->useNANDECC) {
200 retVal = dev->readChunkFromNAND(dev, chunkInNAND, data, spare);
201 if (data && doErrorCorrection) {
202 /* Do ECC correction */
203 /* Todo handle any errors */
204 int eccResult1, eccResult2;
205 __u8 calcEcc[3];
206
207 yaffs_ECCCalculate(data, calcEcc);
208 eccResult1 =
209 yaffs_ECCCorrect(data, spare->ecc1, calcEcc);
210 yaffs_ECCCalculate(&data[256], calcEcc);
211 eccResult2 =
212 yaffs_ECCCorrect(&data[256], spare->ecc2, calcEcc);
213
214 if (eccResult1 > 0) {
215 T(YAFFS_TRACE_ERROR,
216 (TSTR
217 ("**>>yaffs ecc error fix performed on chunk %d:0"
218 TENDSTR), chunkInNAND));
219 dev->eccFixed++;
220 } else if (eccResult1 < 0) {
221 T(YAFFS_TRACE_ERROR,
222 (TSTR
223 ("**>>yaffs ecc error unfixed on chunk %d:0"
224 TENDSTR), chunkInNAND));
225 dev->eccUnfixed++;
226 }
227
228 if (eccResult2 > 0) {
229 T(YAFFS_TRACE_ERROR,
230 (TSTR
231 ("**>>yaffs ecc error fix performed on chunk %d:1"
232 TENDSTR), chunkInNAND));
233 dev->eccFixed++;
234 } else if (eccResult2 < 0) {
235 T(YAFFS_TRACE_ERROR,
236 (TSTR
237 ("**>>yaffs ecc error unfixed on chunk %d:1"
238 TENDSTR), chunkInNAND));
239 dev->eccUnfixed++;
240 }
241
242 if (eccResult1 || eccResult2) {
243 /* We had a data problem on this page */
244 yaffs_HandleReadDataError(dev, chunkInNAND);
245 }
246
247 if (eccResult1 < 0 || eccResult2 < 0)
248 *eccResult = YAFFS_ECC_RESULT_UNFIXED;
249 else if (eccResult1 > 0 || eccResult2 > 0)
250 *eccResult = YAFFS_ECC_RESULT_FIXED;
251 else
252 *eccResult = YAFFS_ECC_RESULT_NO_ERROR;
253 }
254 } else {
255 /* Must allocate enough memory for spare+2*sizeof(int) */
256 /* for ecc results from device. */
257 struct yaffs_NANDSpare nspare;
258 retVal =
259 dev->readChunkFromNAND(dev, chunkInNAND, data,
260 (yaffs_Spare *) & nspare);
261 memcpy(spare, &nspare, sizeof(yaffs_Spare));
262 if (data && doErrorCorrection) {
263 if (nspare.eccres1 > 0) {
264 T(YAFFS_TRACE_ERROR,
265 (TSTR
266 ("**>>mtd ecc error fix performed on chunk %d:0"
267 TENDSTR), chunkInNAND));
268 } else if (nspare.eccres1 < 0) {
269 T(YAFFS_TRACE_ERROR,
270 (TSTR
271 ("**>>mtd ecc error unfixed on chunk %d:0"
272 TENDSTR), chunkInNAND));
273 }
274
275 if (nspare.eccres2 > 0) {
276 T(YAFFS_TRACE_ERROR,
277 (TSTR
278 ("**>>mtd ecc error fix performed on chunk %d:1"
279 TENDSTR), chunkInNAND));
280 } else if (nspare.eccres2 < 0) {
281 T(YAFFS_TRACE_ERROR,
282 (TSTR
283 ("**>>mtd ecc error unfixed on chunk %d:1"
284 TENDSTR), chunkInNAND));
285 }
286
287 if (nspare.eccres1 || nspare.eccres2) {
288 /* We had a data problem on this page */
289 yaffs_HandleReadDataError(dev, chunkInNAND);
290 }
291
292 if (nspare.eccres1 < 0 || nspare.eccres2 < 0)
293 *eccResult = YAFFS_ECC_RESULT_UNFIXED;
294 else if (nspare.eccres1 > 0 || nspare.eccres2 > 0)
295 *eccResult = YAFFS_ECC_RESULT_FIXED;
296 else
297 *eccResult = YAFFS_ECC_RESULT_NO_ERROR;
298
299 }
300 }
301 return retVal;
302 }
303
304 #ifdef NOTYET
yaffs_CheckChunkErased(struct yaffs_DeviceStruct * dev,int chunkInNAND)305 static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
306 int chunkInNAND)
307 {
308
309 static int init = 0;
310 static __u8 cmpbuf[YAFFS_BYTES_PER_CHUNK];
311 static __u8 data[YAFFS_BYTES_PER_CHUNK];
312 /* Might as well always allocate the larger size for */
313 /* dev->useNANDECC == true; */
314 static __u8 spare[sizeof(struct yaffs_NANDSpare)];
315
316 dev->readChunkFromNAND(dev, chunkInNAND, data, (yaffs_Spare *) spare);
317
318 if (!init) {
319 memset(cmpbuf, 0xff, YAFFS_BYTES_PER_CHUNK);
320 init = 1;
321 }
322
323 if (memcmp(cmpbuf, data, YAFFS_BYTES_PER_CHUNK))
324 return YAFFS_FAIL;
325 if (memcmp(cmpbuf, spare, 16))
326 return YAFFS_FAIL;
327
328 return YAFFS_OK;
329
330 }
331 #endif
332
333 /*
334 * Functions for robustisizing
335 */
336
yaffs_HandleReadDataError(yaffs_Device * dev,int chunkInNAND)337 static void yaffs_HandleReadDataError(yaffs_Device * dev, int chunkInNAND)
338 {
339 int blockInNAND = chunkInNAND / dev->nChunksPerBlock;
340
341 /* Mark the block for retirement */
342 yaffs_GetBlockInfo(dev, blockInNAND)->needsRetiring = 1;
343 T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
344 (TSTR("**>>Block %d marked for retirement" TENDSTR), blockInNAND));
345
346 /* TODO:
347 * Just do a garbage collection on the affected block
348 * then retire the block
349 * NB recursion
350 */
351 }
352
353 #ifdef NOTYET
yaffs_CheckWrittenBlock(yaffs_Device * dev,int chunkInNAND)354 static void yaffs_CheckWrittenBlock(yaffs_Device * dev, int chunkInNAND)
355 {
356 }
357
yaffs_HandleWriteChunkOk(yaffs_Device * dev,int chunkInNAND,const __u8 * data,const yaffs_Spare * spare)358 static void yaffs_HandleWriteChunkOk(yaffs_Device * dev, int chunkInNAND,
359 const __u8 * data,
360 const yaffs_Spare * spare)
361 {
362 }
363
yaffs_HandleUpdateChunk(yaffs_Device * dev,int chunkInNAND,const yaffs_Spare * spare)364 static void yaffs_HandleUpdateChunk(yaffs_Device * dev, int chunkInNAND,
365 const yaffs_Spare * spare)
366 {
367 }
368
yaffs_HandleWriteChunkError(yaffs_Device * dev,int chunkInNAND)369 static void yaffs_HandleWriteChunkError(yaffs_Device * dev, int chunkInNAND)
370 {
371 int blockInNAND = chunkInNAND / dev->nChunksPerBlock;
372
373 /* Mark the block for retirement */
374 yaffs_GetBlockInfo(dev, blockInNAND)->needsRetiring = 1;
375 /* Delete the chunk */
376 yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
377 }
378
yaffs_VerifyCompare(const __u8 * d0,const __u8 * d1,const yaffs_Spare * s0,const yaffs_Spare * s1)379 static int yaffs_VerifyCompare(const __u8 * d0, const __u8 * d1,
380 const yaffs_Spare * s0, const yaffs_Spare * s1)
381 {
382
383 if (memcmp(d0, d1, YAFFS_BYTES_PER_CHUNK) != 0 ||
384 s0->tagByte0 != s1->tagByte0 ||
385 s0->tagByte1 != s1->tagByte1 ||
386 s0->tagByte2 != s1->tagByte2 ||
387 s0->tagByte3 != s1->tagByte3 ||
388 s0->tagByte4 != s1->tagByte4 ||
389 s0->tagByte5 != s1->tagByte5 ||
390 s0->tagByte6 != s1->tagByte6 ||
391 s0->tagByte7 != s1->tagByte7 ||
392 s0->ecc1[0] != s1->ecc1[0] ||
393 s0->ecc1[1] != s1->ecc1[1] ||
394 s0->ecc1[2] != s1->ecc1[2] ||
395 s0->ecc2[0] != s1->ecc2[0] ||
396 s0->ecc2[1] != s1->ecc2[1] || s0->ecc2[2] != s1->ecc2[2]) {
397 return 0;
398 }
399
400 return 1;
401 }
402 #endif /* NOTYET */
403
yaffs_TagsCompatabilityWriteChunkWithTagsToNAND(yaffs_Device * dev,int chunkInNAND,const __u8 * data,const yaffs_ExtendedTags * eTags)404 int yaffs_TagsCompatabilityWriteChunkWithTagsToNAND(yaffs_Device * dev,
405 int chunkInNAND,
406 const __u8 * data,
407 const yaffs_ExtendedTags *
408 eTags)
409 {
410 yaffs_Spare spare;
411 yaffs_Tags tags;
412
413 yaffs_SpareInitialise(&spare);
414
415 if (eTags->chunkDeleted) {
416 spare.pageStatus = 0;
417 } else {
418 tags.objectId = eTags->objectId;
419 tags.chunkId = eTags->chunkId;
420 tags.byteCount = eTags->byteCount;
421 tags.serialNumber = eTags->serialNumber;
422
423 if (!dev->useNANDECC && data) {
424 yaffs_CalcECC(data, &spare);
425 }
426 yaffs_LoadTagsIntoSpare(&spare, &tags);
427
428 }
429
430 return yaffs_WriteChunkToNAND(dev, chunkInNAND, data, &spare);
431 }
432
yaffs_TagsCompatabilityReadChunkWithTagsFromNAND(yaffs_Device * dev,int chunkInNAND,__u8 * data,yaffs_ExtendedTags * eTags)433 int yaffs_TagsCompatabilityReadChunkWithTagsFromNAND(yaffs_Device * dev,
434 int chunkInNAND,
435 __u8 * data,
436 yaffs_ExtendedTags * eTags)
437 {
438
439 yaffs_Spare spare;
440 yaffs_Tags tags;
441 yaffs_ECCResult eccResult;
442
443 static yaffs_Spare spareFF;
444 static int init;
445
446 if (!init) {
447 memset(&spareFF, 0xFF, sizeof(spareFF));
448 init = 1;
449 }
450
451 if (yaffs_ReadChunkFromNAND
452 (dev, chunkInNAND, data, &spare, &eccResult, 1)) {
453 /* eTags may be NULL */
454 if (eTags) {
455
456 int deleted =
457 (yaffs_CountBits(spare.pageStatus) < 7) ? 1 : 0;
458
459 eTags->chunkDeleted = deleted;
460 eTags->eccResult = eccResult;
461 eTags->blockBad = 0; /* We're reading it */
462 /* therefore it is not a bad block */
463 eTags->chunkUsed =
464 (memcmp(&spareFF, &spare, sizeof(spareFF)) !=
465 0) ? 1 : 0;
466
467 if (eTags->chunkUsed) {
468 yaffs_GetTagsFromSpare(dev, &spare, &tags);
469
470 eTags->objectId = tags.objectId;
471 eTags->chunkId = tags.chunkId;
472 eTags->byteCount = tags.byteCount;
473 eTags->serialNumber = tags.serialNumber;
474 }
475 }
476
477 return YAFFS_OK;
478 } else {
479 return YAFFS_FAIL;
480 }
481 }
482
yaffs_TagsCompatabilityMarkNANDBlockBad(struct yaffs_DeviceStruct * dev,int blockInNAND)483 int yaffs_TagsCompatabilityMarkNANDBlockBad(struct yaffs_DeviceStruct *dev,
484 int blockInNAND)
485 {
486
487 yaffs_Spare spare;
488
489 memset(&spare, 0xff, sizeof(yaffs_Spare));
490
491 spare.blockStatus = 'Y';
492
493 yaffs_WriteChunkToNAND(dev, blockInNAND * dev->nChunksPerBlock, NULL,
494 &spare);
495 yaffs_WriteChunkToNAND(dev, blockInNAND * dev->nChunksPerBlock + 1,
496 NULL, &spare);
497
498 return YAFFS_OK;
499
500 }
501
yaffs_TagsCompatabilityQueryNANDBlock(struct yaffs_DeviceStruct * dev,int blockNo,yaffs_BlockState * state,int * sequenceNumber)502 int yaffs_TagsCompatabilityQueryNANDBlock(struct yaffs_DeviceStruct *dev,
503 int blockNo, yaffs_BlockState *
504 state,
505 int *sequenceNumber)
506 {
507
508 yaffs_Spare spare0, spare1;
509 static yaffs_Spare spareFF;
510 static int init;
511 yaffs_ECCResult dummy;
512
513 if (!init) {
514 memset(&spareFF, 0xFF, sizeof(spareFF));
515 init = 1;
516 }
517
518 *sequenceNumber = 0;
519
520 yaffs_ReadChunkFromNAND(dev, blockNo * dev->nChunksPerBlock, NULL,
521 &spare0, &dummy, 1);
522 yaffs_ReadChunkFromNAND(dev, blockNo * dev->nChunksPerBlock + 1, NULL,
523 &spare1, &dummy, 1);
524
525 if (yaffs_CountBits(spare0.blockStatus & spare1.blockStatus) < 7)
526 *state = YAFFS_BLOCK_STATE_DEAD;
527 else if (memcmp(&spareFF, &spare0, sizeof(spareFF)) == 0)
528 *state = YAFFS_BLOCK_STATE_EMPTY;
529 else
530 *state = YAFFS_BLOCK_STATE_NEEDS_SCANNING;
531
532 return YAFFS_OK;
533 }
534