--- /dev/null
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2011 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(struct yaffs_dev *dev, int nand_chunk);
+
+
+/********** Tags ECC calculations *********/
+
+void yaffs_calc_ecc(const u8 *data, struct yaffs_spare *spare)
+{
+ yaffs_ecc_calc(data, spare->ecc1);
+ yaffs_ecc_calc(&data[256], spare->ecc2);
+}
+
+void yaffs_calc_tags_ecc(struct yaffs_tags *tags)
+{
+ /* Calculate an ecc */
+ unsigned char *b = ((union yaffs_tags_union *)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(struct yaffs_tags *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 = ((union yaffs_tags_union *)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(struct yaffs_spare *spare_ptr,
+ struct yaffs_tags *tags_ptr)
+{
+ union yaffs_tags_union *tu = (union yaffs_tags_union *)tags_ptr;
+
+ yaffs_calc_tags_ecc(tags_ptr);
+
+ spare_ptr->tb0 = tu->as_bytes[0];
+ spare_ptr->tb1 = tu->as_bytes[1];
+ spare_ptr->tb2 = tu->as_bytes[2];
+ spare_ptr->tb3 = tu->as_bytes[3];
+ spare_ptr->tb4 = tu->as_bytes[4];
+ spare_ptr->tb5 = tu->as_bytes[5];
+ spare_ptr->tb6 = tu->as_bytes[6];
+ spare_ptr->tb7 = tu->as_bytes[7];
+}
+
+static void yaffs_get_tags_from_spare(struct yaffs_dev *dev,
+ struct yaffs_spare *spare_ptr,
+ struct yaffs_tags *tags_ptr)
+{
+ union yaffs_tags_union *tu = (union yaffs_tags_union *)tags_ptr;
+ int result;
+
+ tu->as_bytes[0] = spare_ptr->tb0;
+ tu->as_bytes[1] = spare_ptr->tb1;
+ tu->as_bytes[2] = spare_ptr->tb2;
+ tu->as_bytes[3] = spare_ptr->tb3;
+ tu->as_bytes[4] = spare_ptr->tb4;
+ tu->as_bytes[5] = spare_ptr->tb5;
+ tu->as_bytes[6] = spare_ptr->tb6;
+ tu->as_bytes[7] = spare_ptr->tb7;
+
+ result = yaffs_check_tags_ecc(tags_ptr);
+ if (result > 0)
+ dev->n_tags_ecc_fixed++;
+ else if (result < 0)
+ dev->n_tags_ecc_unfixed++;
+}
+
+static void yaffs_spare_init(struct yaffs_spare *spare)
+{
+ memset(spare, 0xff, sizeof(struct yaffs_spare));
+}
+
+static int yaffs_wr_nand(struct yaffs_dev *dev,
+ int nand_chunk, const u8 *data,
+ struct yaffs_spare *spare)
+{
+ if (nand_chunk < dev->param.start_block * dev->param.chunks_per_block) {
+ yaffs_trace(YAFFS_TRACE_ERROR,
+ "**>> yaffs chunk %d is not valid",
+ 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 *dev,
+ int nand_chunk,
+ u8 *data,
+ struct yaffs_spare *spare,
+ enum yaffs_ecc_result *ecc_result,
+ int correct_errors)
+{
+ int ret_val;
+ struct yaffs_spare local_spare;
+
+ if (!spare) {
+ /* If we don't have a real spare, then we use a local one. */
+ /* Need this for the calculation of the ecc */
+ spare = &local_spare;
+ }
+
+ if (!dev->param.use_nand_ecc) {
+ ret_val =
+ dev->param.read_chunk_fn(dev, nand_chunk, data, spare);
+ if (data && correct_errors) {
+ /* Do ECC correction */
+ /* Todo handle any errors */
+ int ecc_result1, ecc_result2;
+ u8 calc_ecc[3];
+
+ yaffs_ecc_calc(data, calc_ecc);
+ ecc_result1 =
+ yaffs_ecc_correct(data, spare->ecc1, calc_ecc);
+ yaffs_ecc_calc(&data[256], calc_ecc);
+ ecc_result2 =
+ yaffs_ecc_correct(&data[256], spare->ecc2,
+ calc_ecc);
+
+ if (ecc_result1 > 0) {
+ yaffs_trace(YAFFS_TRACE_ERROR,
+ "**>>yaffs ecc error fix performed on chunk %d:0",
+ nand_chunk);
+ dev->n_ecc_fixed++;
+ } else if (ecc_result1 < 0) {
+ yaffs_trace(YAFFS_TRACE_ERROR,
+ "**>>yaffs ecc error unfixed on chunk %d:0",
+ nand_chunk);
+ dev->n_ecc_unfixed++;
+ }
+
+ if (ecc_result2 > 0) {
+ yaffs_trace(YAFFS_TRACE_ERROR,
+ "**>>yaffs ecc error fix performed on chunk %d:1",
+ nand_chunk);
+ dev->n_ecc_fixed++;
+ } else if (ecc_result2 < 0) {
+ yaffs_trace(YAFFS_TRACE_ERROR,
+ "**>>yaffs ecc error unfixed on chunk %d:1",
+ 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));
+
+ ret_val = dev->param.read_chunk_fn(dev, nand_chunk, data,
+ (struct yaffs_spare *)
+ &nspare);
+ memcpy(spare, &nspare, sizeof(struct yaffs_spare));
+ if (data && correct_errors) {
+ if (nspare.eccres1 > 0) {
+ yaffs_trace(YAFFS_TRACE_ERROR,
+ "**>>mtd ecc error fix performed on chunk %d:0",
+ nand_chunk);
+ } else if (nspare.eccres1 < 0) {
+ yaffs_trace(YAFFS_TRACE_ERROR,
+ "**>>mtd ecc error unfixed on chunk %d:0",
+ nand_chunk);
+ }
+
+ if (nspare.eccres2 > 0) {
+ yaffs_trace(YAFFS_TRACE_ERROR,
+ "**>>mtd ecc error fix performed on chunk %d:1",
+ nand_chunk);
+ } else if (nspare.eccres2 < 0) {
+ yaffs_trace(YAFFS_TRACE_ERROR,
+ "**>>mtd ecc error unfixed on chunk %d:1",
+ 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 ret_val;
+}
+
+/*
+ * Functions for robustisizing
+ */
+
+static void yaffs_handle_rd_data_error(struct yaffs_dev *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;
+ yaffs_trace(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
+ "**>>Block %d marked for retirement",
+ flash_block);
+
+ /* TODO:
+ * Just do a garbage collection on the affected block
+ * then retire the block
+ * NB recursion
+ */
+}
+
+int yaffs_tags_compat_wr(struct yaffs_dev *dev,
+ int nand_chunk,
+ const u8 *data, const struct yaffs_ext_tags *ext_tags)
+{
+ struct yaffs_spare spare;
+ struct yaffs_tags tags;
+
+ yaffs_spare_init(&spare);
+
+ if (ext_tags->is_deleted)
+ spare.page_status = 0;
+ else {
+ tags.obj_id = ext_tags->obj_id;
+ tags.chunk_id = ext_tags->chunk_id;
+
+ tags.n_bytes_lsb = ext_tags->n_bytes & (1024 - 1);
+
+ if (dev->data_bytes_per_chunk >= 1024)
+ tags.n_bytes_msb = (ext_tags->n_bytes >> 10) & 3;
+ else
+ tags.n_bytes_msb = 3;
+
+ tags.serial_number = ext_tags->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(struct yaffs_dev *dev,
+ int nand_chunk,
+ u8 *data, struct yaffs_ext_tags *ext_tags)
+{
+ struct yaffs_spare spare;
+ struct yaffs_tags tags;
+ enum yaffs_ecc_result ecc_result = YAFFS_ECC_RESULT_UNKNOWN;
+ static struct yaffs_spare spare_ff;
+ static int init;
+ int deleted;
+
+ if (!init) {
+ memset(&spare_ff, 0xff, sizeof(spare_ff));
+ init = 1;
+ }
+
+ if (!yaffs_rd_chunk_nand(dev, nand_chunk,
+ data, &spare, &ecc_result, 1))
+ return YAFFS_FAIL;
+
+ /* ext_tags may be NULL */
+ if (!ext_tags)
+ return YAFFS_OK;
+
+ deleted = (hweight8(spare.page_status) < 7) ? 1 : 0;
+
+ ext_tags->is_deleted = deleted;
+ ext_tags->ecc_result = ecc_result;
+ ext_tags->block_bad = 0; /* We're reading it */
+ /* therefore it is not a bad block */
+ ext_tags->chunk_used =
+ memcmp(&spare_ff, &spare, sizeof(spare_ff)) ? 1 : 0;
+
+ if (ext_tags->chunk_used) {
+ yaffs_get_tags_from_spare(dev, &spare, &tags);
+ ext_tags->obj_id = tags.obj_id;
+ ext_tags->chunk_id = tags.chunk_id;
+ ext_tags->n_bytes = tags.n_bytes_lsb;
+
+ if (dev->data_bytes_per_chunk >= 1024)
+ ext_tags->n_bytes |=
+ (((unsigned)tags.n_bytes_msb) << 10);
+
+ ext_tags->serial_number = tags.serial_number;
+ }
+
+ return YAFFS_OK;
+}
+
+int yaffs_tags_compat_mark_bad(struct yaffs_dev *dev, int flash_block)
+{
+ struct yaffs_spare spare;
+
+ memset(&spare, 0xff, sizeof(struct 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 *dev,
+ int block_no,
+ enum yaffs_block_state *state,
+ u32 *seq_number)
+{
+ struct yaffs_spare spare0, spare1;
+ static struct yaffs_spare spare_ff;
+ static int init;
+ enum yaffs_ecc_result dummy;
+
+ if (!init) {
+ memset(&spare_ff, 0xff, sizeof(spare_ff));
+ 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 (hweight8(spare0.block_status & spare1.block_status) < 7)
+ *state = YAFFS_BLOCK_STATE_DEAD;
+ else if (memcmp(&spare_ff, &spare0, sizeof(spare_ff)) == 0)
+ *state = YAFFS_BLOCK_STATE_EMPTY;
+ else
+ *state = YAFFS_BLOCK_STATE_NEEDS_SCAN;
+
+ return YAFFS_OK;
+}
Code Review / kvmfornfv.git / blobdiff