| /* |
| * YAFFS: Yet Another Flash File System. A NAND-flash specific file system. |
| * |
| * Copyright (C) 2002-2010 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" |
| #include "yaffs_getblockinfo.h" |
| #include "yaffs_trace.h" |
| |
| static void yaffs_handle_rd_data_error(yaffs_dev_t *dev, int nand_chunk); |
| #ifdef NOTYET |
| static void yaffs_check_written_block(yaffs_dev_t *dev, int nand_chunk); |
| static void yaffs_handle_chunk_wr_ok(yaffs_dev_t *dev, int nand_chunk, |
| const __u8 *data, |
| const yaffs_spare *spare); |
| static void yaffs_handle_chunk_update(yaffs_dev_t *dev, int nand_chunk, |
| const yaffs_spare *spare); |
| static void yaffs_handle_chunk_wr_error(yaffs_dev_t *dev, int nand_chunk); |
| #endif |
| |
| static const char yaffs_count_bits_table[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_count_bits(__u8 x) |
| { |
| int retVal; |
| retVal = yaffs_count_bits_table[x]; |
| return retVal; |
| } |
| |
| /********** Tags ECC calculations *********/ |
| |
| void yaffs_calc_ecc(const __u8 *data, yaffs_spare *spare) |
| { |
| yaffs_ecc_cacl(data, spare->ecc1); |
| yaffs_ecc_cacl(&data[256], spare->ecc2); |
| } |
| |
| void yaffs_calc_tags_ecc(yaffs_tags_t *tags) |
| { |
| /* Calculate an ecc */ |
| |
| unsigned char *b = ((yaffs_tags_union_t *) tags)->as_bytes; |
| 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_check_tags_ecc(yaffs_tags_t *tags) |
| { |
| unsigned ecc = tags->ecc; |
| |
| yaffs_calc_tags_ecc(tags); |
| |
| ecc ^= tags->ecc; |
| |
| if (ecc && ecc <= 64) { |
| /* TODO: Handle the failure better. Retire? */ |
| unsigned char *b = ((yaffs_tags_union_t *) tags)->as_bytes; |
| |
| ecc--; |
| |
| b[ecc / 8] ^= (1 << (ecc & 7)); |
| |
| /* Now recvalc the ecc */ |
| yaffs_calc_tags_ecc(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_load_tags_to_spare(yaffs_spare *sparePtr, |
| yaffs_tags_t *tagsPtr) |
| { |
| yaffs_tags_union_t *tu = (yaffs_tags_union_t *) tagsPtr; |
| |
| yaffs_calc_tags_ecc(tagsPtr); |
| |
| sparePtr->tb0 = tu->as_bytes[0]; |
| sparePtr->tb1 = tu->as_bytes[1]; |
| sparePtr->tb2 = tu->as_bytes[2]; |
| sparePtr->tb3 = tu->as_bytes[3]; |
| sparePtr->tb4 = tu->as_bytes[4]; |
| sparePtr->tb5 = tu->as_bytes[5]; |
| sparePtr->tb6 = tu->as_bytes[6]; |
| sparePtr->tb7 = tu->as_bytes[7]; |
| } |
| |
| static void yaffs_get_tags_from_spare(yaffs_dev_t *dev, yaffs_spare *sparePtr, |
| yaffs_tags_t *tagsPtr) |
| { |
| yaffs_tags_union_t *tu = (yaffs_tags_union_t *) tagsPtr; |
| int result; |
| |
| tu->as_bytes[0] = sparePtr->tb0; |
| tu->as_bytes[1] = sparePtr->tb1; |
| tu->as_bytes[2] = sparePtr->tb2; |
| tu->as_bytes[3] = sparePtr->tb3; |
| tu->as_bytes[4] = sparePtr->tb4; |
| tu->as_bytes[5] = sparePtr->tb5; |
| tu->as_bytes[6] = sparePtr->tb6; |
| tu->as_bytes[7] = sparePtr->tb7; |
| |
| result = yaffs_check_tags_ecc(tagsPtr); |
| if (result > 0) |
| dev->n_tags_ecc_fixed++; |
| else if (result < 0) |
| dev->n_tags_ecc_unfixed++; |
| } |
| |
| static void yaffs_spare_init(yaffs_spare *spare) |
| { |
| memset(spare, 0xFF, sizeof(yaffs_spare)); |
| } |
| |
| static int yaffs_wr_nand(struct yaffs_dev_s *dev, |
| int nand_chunk, const __u8 *data, |
| yaffs_spare *spare) |
| { |
| if (nand_chunk < dev->param.start_block * dev->param.chunks_per_block) { |
| T(YAFFS_TRACE_ERROR, |
| (TSTR("**>> yaffs chunk %d is not valid" TENDSTR), |
| nand_chunk)); |
| return YAFFS_FAIL; |
| } |
| |
| return dev->param.write_chunk_fn(dev, nand_chunk, data, spare); |
| } |
| |
| static int yaffs_rd_chunk_nand(struct yaffs_dev_s *dev, |
| int nand_chunk, |
| __u8 *data, |
| yaffs_spare *spare, |
| yaffs_ecc_result *ecc_result, |
| int doErrorCorrection) |
| { |
| int retVal; |
| yaffs_spare localSpare; |
| |
| 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->param.use_nand_ecc) { |
| retVal = dev->param.read_chunk_fn(dev, nand_chunk, data, spare); |
| if (data && doErrorCorrection) { |
| /* Do ECC correction */ |
| /* Todo handle any errors */ |
| int ecc_result1, ecc_result2; |
| __u8 calcEcc[3]; |
| |
| yaffs_ecc_cacl(data, calcEcc); |
| ecc_result1 = |
| yaffs_ecc_correct(data, spare->ecc1, calcEcc); |
| yaffs_ecc_cacl(&data[256], calcEcc); |
| ecc_result2 = |
| yaffs_ecc_correct(&data[256], spare->ecc2, calcEcc); |
| |
| if (ecc_result1 > 0) { |
| T(YAFFS_TRACE_ERROR, |
| (TSTR |
| ("**>>yaffs ecc error fix performed on chunk %d:0" |
| TENDSTR), nand_chunk)); |
| dev->n_ecc_fixed++; |
| } else if (ecc_result1 < 0) { |
| T(YAFFS_TRACE_ERROR, |
| (TSTR |
| ("**>>yaffs ecc error unfixed on chunk %d:0" |
| TENDSTR), nand_chunk)); |
| dev->n_ecc_unfixed++; |
| } |
| |
| if (ecc_result2 > 0) { |
| T(YAFFS_TRACE_ERROR, |
| (TSTR |
| ("**>>yaffs ecc error fix performed on chunk %d:1" |
| TENDSTR), nand_chunk)); |
| dev->n_ecc_fixed++; |
| } else if (ecc_result2 < 0) { |
| T(YAFFS_TRACE_ERROR, |
| (TSTR |
| ("**>>yaffs ecc error unfixed on chunk %d:1" |
| TENDSTR), nand_chunk)); |
| dev->n_ecc_unfixed++; |
| } |
| |
| if (ecc_result1 || ecc_result2) { |
| /* We had a data problem on this page */ |
| yaffs_handle_rd_data_error(dev, nand_chunk); |
| } |
| |
| if (ecc_result1 < 0 || ecc_result2 < 0) |
| *ecc_result = YAFFS_ECC_RESULT_UNFIXED; |
| else if (ecc_result1 > 0 || ecc_result2 > 0) |
| *ecc_result = YAFFS_ECC_RESULT_FIXED; |
| else |
| *ecc_result = YAFFS_ECC_RESULT_NO_ERROR; |
| } |
| } else { |
| /* Must allocate enough memory for spare+2*sizeof(int) */ |
| /* for ecc results from device. */ |
| struct yaffs_nand_spare nspare; |
| |
| memset(&nspare, 0, sizeof(nspare)); |
| |
| retVal = dev->param.read_chunk_fn(dev, nand_chunk, 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), nand_chunk)); |
| } else if (nspare.eccres1 < 0) { |
| T(YAFFS_TRACE_ERROR, |
| (TSTR |
| ("**>>mtd ecc error unfixed on chunk %d:0" |
| TENDSTR), nand_chunk)); |
| } |
| |
| if (nspare.eccres2 > 0) { |
| T(YAFFS_TRACE_ERROR, |
| (TSTR |
| ("**>>mtd ecc error fix performed on chunk %d:1" |
| TENDSTR), nand_chunk)); |
| } else if (nspare.eccres2 < 0) { |
| T(YAFFS_TRACE_ERROR, |
| (TSTR |
| ("**>>mtd ecc error unfixed on chunk %d:1" |
| TENDSTR), nand_chunk)); |
| } |
| |
| if (nspare.eccres1 || nspare.eccres2) { |
| /* We had a data problem on this page */ |
| yaffs_handle_rd_data_error(dev, nand_chunk); |
| } |
| |
| if (nspare.eccres1 < 0 || nspare.eccres2 < 0) |
| *ecc_result = YAFFS_ECC_RESULT_UNFIXED; |
| else if (nspare.eccres1 > 0 || nspare.eccres2 > 0) |
| *ecc_result = YAFFS_ECC_RESULT_FIXED; |
| else |
| *ecc_result = YAFFS_ECC_RESULT_NO_ERROR; |
| |
| } |
| } |
| return retVal; |
| } |
| |
| #ifdef NOTYET |
| static int yaffs_check_chunk_erased(struct yaffs_dev_s *dev, |
| int nand_chunk) |
| { |
| static int init; |
| static __u8 cmpbuf[YAFFS_BYTES_PER_CHUNK]; |
| static __u8 data[YAFFS_BYTES_PER_CHUNK]; |
| /* Might as well always allocate the larger size for */ |
| /* dev->param.use_nand_ecc == true; */ |
| static __u8 spare[sizeof(struct yaffs_nand_spare)]; |
| |
| dev->param.read_chunk_fn(dev, nand_chunk, 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_handle_rd_data_error(yaffs_dev_t *dev, int nand_chunk) |
| { |
| int flash_block = nand_chunk / dev->param.chunks_per_block; |
| |
| /* Mark the block for retirement */ |
| yaffs_get_block_info(dev, flash_block + dev->block_offset)->needs_retiring = 1; |
| T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS, |
| (TSTR("**>>Block %d marked for retirement" TENDSTR), flash_block)); |
| |
| /* TODO: |
| * Just do a garbage collection on the affected block |
| * then retire the block |
| * NB recursion |
| */ |
| } |
| |
| #ifdef NOTYET |
| static void yaffs_check_written_block(yaffs_dev_t *dev, int nand_chunk) |
| { |
| } |
| |
| static void yaffs_handle_chunk_wr_ok(yaffs_dev_t *dev, int nand_chunk, |
| const __u8 *data, |
| const yaffs_spare *spare) |
| { |
| } |
| |
| static void yaffs_handle_chunk_update(yaffs_dev_t *dev, int nand_chunk, |
| const yaffs_spare *spare) |
| { |
| } |
| |
| static void yaffs_handle_chunk_wr_error(yaffs_dev_t *dev, int nand_chunk) |
| { |
| int flash_block = nand_chunk / dev->param.chunks_per_block; |
| |
| /* Mark the block for retirement */ |
| yaffs_get_block_info(dev, flash_block)->needs_retiring = 1; |
| /* Delete the chunk */ |
| yaffs_chunk_del(dev, nand_chunk, 1, __LINE__); |
| } |
| |
| static int yaffs_verify_cmp(const __u8 *d0, const __u8 *d1, |
| const yaffs_spare *s0, const yaffs_spare *s1) |
| { |
| |
| if (memcmp(d0, d1, YAFFS_BYTES_PER_CHUNK) != 0 || |
| s0->tb0 != s1->tb0 || |
| s0->tb1 != s1->tb1 || |
| s0->tb2 != s1->tb2 || |
| s0->tb3 != s1->tb3 || |
| s0->tb4 != s1->tb4 || |
| s0->tb5 != s1->tb5 || |
| s0->tb6 != s1->tb6 || |
| s0->tb7 != s1->tb7 || |
| 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_tags_compat_wr(yaffs_dev_t *dev, |
| int nand_chunk, |
| const __u8 *data, |
| const yaffs_ext_tags *eTags) |
| { |
| yaffs_spare spare; |
| yaffs_tags_t tags; |
| |
| yaffs_spare_init(&spare); |
| |
| if (eTags->is_deleted) |
| spare.page_status = 0; |
| else { |
| tags.obj_id = eTags->obj_id; |
| tags.chunk_id = eTags->chunk_id; |
| |
| tags.n_bytes_lsb = eTags->n_bytes & 0x3ff; |
| |
| if (dev->data_bytes_per_chunk >= 1024) |
| tags.n_bytes_msb = (eTags->n_bytes >> 10) & 3; |
| else |
| tags.n_bytes_msb = 3; |
| |
| |
| tags.serial_number = eTags->serial_number; |
| |
| if (!dev->param.use_nand_ecc && data) |
| yaffs_calc_ecc(data, &spare); |
| |
| yaffs_load_tags_to_spare(&spare, &tags); |
| |
| } |
| |
| return yaffs_wr_nand(dev, nand_chunk, data, &spare); |
| } |
| |
| int yaffs_tags_compat_rd(yaffs_dev_t *dev, |
| int nand_chunk, |
| __u8 *data, |
| yaffs_ext_tags *eTags) |
| { |
| |
| yaffs_spare spare; |
| yaffs_tags_t tags; |
| yaffs_ecc_result ecc_result = YAFFS_ECC_RESULT_UNKNOWN; |
| |
| static yaffs_spare spareFF; |
| static int init; |
| |
| if (!init) { |
| memset(&spareFF, 0xFF, sizeof(spareFF)); |
| init = 1; |
| } |
| |
| if (yaffs_rd_chunk_nand |
| (dev, nand_chunk, data, &spare, &ecc_result, 1)) { |
| /* eTags may be NULL */ |
| if (eTags) { |
| |
| int deleted = |
| (yaffs_count_bits(spare.page_status) < 7) ? 1 : 0; |
| |
| eTags->is_deleted = deleted; |
| eTags->ecc_result = ecc_result; |
| eTags->block_bad = 0; /* We're reading it */ |
| /* therefore it is not a bad block */ |
| eTags->chunk_used = |
| (memcmp(&spareFF, &spare, sizeof(spareFF)) != |
| 0) ? 1 : 0; |
| |
| if (eTags->chunk_used) { |
| yaffs_get_tags_from_spare(dev, &spare, &tags); |
| |
| eTags->obj_id = tags.obj_id; |
| eTags->chunk_id = tags.chunk_id; |
| eTags->n_bytes = tags.n_bytes_lsb; |
| |
| if (dev->data_bytes_per_chunk >= 1024) |
| eTags->n_bytes |= (((unsigned) tags.n_bytes_msb) << 10); |
| |
| eTags->serial_number = tags.serial_number; |
| } |
| } |
| |
| return YAFFS_OK; |
| } else { |
| return YAFFS_FAIL; |
| } |
| } |
| |
| int yaffs_tags_compat_mark_bad(struct yaffs_dev_s *dev, |
| int flash_block) |
| { |
| |
| yaffs_spare spare; |
| |
| memset(&spare, 0xff, sizeof(yaffs_spare)); |
| |
| spare.block_status = 'Y'; |
| |
| yaffs_wr_nand(dev, flash_block * dev->param.chunks_per_block, NULL, |
| &spare); |
| yaffs_wr_nand(dev, flash_block * dev->param.chunks_per_block + 1, |
| NULL, &spare); |
| |
| return YAFFS_OK; |
| |
| } |
| |
| int yaffs_tags_compat_query_block(struct yaffs_dev_s *dev, |
| int block_no, |
| yaffs_block_state_t *state, |
| __u32 *seq_number) |
| { |
| |
| yaffs_spare spare0, spare1; |
| static yaffs_spare spareFF; |
| static int init; |
| yaffs_ecc_result dummy; |
| |
| if (!init) { |
| memset(&spareFF, 0xFF, sizeof(spareFF)); |
| init = 1; |
| } |
| |
| *seq_number = 0; |
| |
| yaffs_rd_chunk_nand(dev, block_no * dev->param.chunks_per_block, NULL, |
| &spare0, &dummy, 1); |
| yaffs_rd_chunk_nand(dev, block_no * dev->param.chunks_per_block + 1, NULL, |
| &spare1, &dummy, 1); |
| |
| if (yaffs_count_bits(spare0.block_status & spare1.block_status) < 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; |
| } |