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Message-Id: <1288636877-7964-22-git-send-email-tdent48227@gmail.com>
Date: Mon, 1 Nov 2010 14:41:09 -0400
From: Tracey Dent <tdent48227@...il.com>
To: greg@...ah.com
Cc: manningc2@...rix.gen.nz, linux-kernel@...r.kernel.org,
linux-fsdevel@...r.kernel.org, Tracey Dent <tdent48227@...il.com>
Subject: [PATCH 21/29] Staging: yaffs2: yaffs_tagscompact: Add files
Adding files to yaffs2 directory.
Signed-off-by: Tracey Dent <tdent48227@...il.com>
---
drivers/staging/yaffs2/yaffs_tagscompat.c | 539 +++++++++++++++++++++++++++++
drivers/staging/yaffs2/yaffs_tagscompat.h | 39 ++
2 files changed, 578 insertions(+), 0 deletions(-)
create mode 100644 drivers/staging/yaffs2/yaffs_tagscompat.c
create mode 100644 drivers/staging/yaffs2/yaffs_tagscompat.h
diff --git a/drivers/staging/yaffs2/yaffs_tagscompat.c b/drivers/staging/yaffs2/yaffs_tagscompat.c
new file mode 100644
index 0000000..1e910f2
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_tagscompat.c
@@ -0,0 +1,539 @@
+/*
+ * 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@...ph1.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 ret_val;
+ ret_val = yaffs_count_bits_table[x];
+ return ret_val;
+}
+
+/********** 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 *spare_ptr,
+ yaffs_tags_t *tags_ptr)
+{
+ yaffs_tags_union_t *tu = (yaffs_tags_union_t *) 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(yaffs_dev_t *dev, yaffs_spare *spare_ptr,
+ yaffs_tags_t *tags_ptr)
+{
+ yaffs_tags_union_t *tu = (yaffs_tags_union_t *) 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(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 correct_errors)
+{
+ int ret_val;
+ yaffs_spare local_spare;
+
+ 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 = &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_cacl(data, calc_ecc);
+ ecc_result1 =
+ yaffs_ecc_correct(data, spare->ecc1, calc_ecc);
+ yaffs_ecc_cacl(&data[256], calc_ecc);
+ ecc_result2 =
+ yaffs_ecc_correct(&data[256], spare->ecc2, calc_ecc);
+
+ 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));
+
+ ret_val = dev->param.read_chunk_fn(dev, nand_chunk, data,
+ (yaffs_spare *) &nspare);
+ memcpy(spare, &nspare, sizeof(yaffs_spare));
+ if (data && correct_errors) {
+ 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 ret_val;
+}
+
+#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 *ext_tags)
+{
+ yaffs_spare spare;
+ yaffs_tags_t 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 & 0x3ff;
+
+ 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(yaffs_dev_t *dev,
+ int nand_chunk,
+ __u8 *data,
+ yaffs_ext_tags *ext_tags)
+{
+
+ yaffs_spare spare;
+ yaffs_tags_t tags;
+ yaffs_ecc_result ecc_result = YAFFS_ECC_RESULT_UNKNOWN;
+
+ static yaffs_spare spare_ff;
+ static int init;
+
+ if (!init) {
+ memset(&spare_ff, 0xFF, sizeof(spare_ff));
+ init = 1;
+ }
+
+ if (yaffs_rd_chunk_nand
+ (dev, nand_chunk, data, &spare, &ecc_result, 1)) {
+ /* ext_tags may be NULL */
+ if (ext_tags) {
+
+ int deleted =
+ (yaffs_count_bits(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)) !=
+ 0) ? 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;
+ } 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 spare_ff;
+ static int init;
+ 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 (yaffs_count_bits(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_SCANNING;
+
+ return YAFFS_OK;
+}
diff --git a/drivers/staging/yaffs2/yaffs_tagscompat.h b/drivers/staging/yaffs2/yaffs_tagscompat.h
new file mode 100644
index 0000000..889bf5f4
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_tagscompat.h
@@ -0,0 +1,39 @@
+/*
+ * 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@...ph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_TAGSCOMPAT_H__
+#define __YAFFS_TAGSCOMPAT_H__
+
+#include "yaffs_guts.h"
+int yaffs_tags_compat_wr(yaffs_dev_t *dev,
+ int nand_chunk,
+ const __u8 *data,
+ const yaffs_ext_tags *tags);
+int yaffs_tags_compat_rd(yaffs_dev_t *dev,
+ int nand_chunk,
+ __u8 *data,
+ yaffs_ext_tags *tags);
+int yaffs_tags_compat_mark_bad(struct yaffs_dev_s *dev,
+ int block_no);
+int yaffs_tags_compat_query_block(struct yaffs_dev_s *dev,
+ int block_no,
+ yaffs_block_state_t *state,
+ __u32 *seq_number);
+
+void yaffs_calc_tags_ecc(yaffs_tags_t *tags);
+int yaffs_check_tags_ecc(yaffs_tags_t *tags);
+int yaffs_count_bits(__u8 byte);
+
+#endif
--
1.7.3.2.146.gca209
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