yaffs_tagsmarshall.c

   1 /*
   2  * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
   3  *
   4  * Copyright (C) 2002-2011 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  * This file handles the marshalling (ie internal<-->external structure
  14  * translation between the internal tags and the stored tags in Yaffs2-style
  15  * tags storage.
  16  */
  17
  18 #include "yaffs_guts.h"
  19 #include "yaffs_trace.h"
  20 #include "yaffs_packedtags2.h"
  21
  22 static int yaffs_tags_marshall_write(struct yaffs_dev *dev,
  23                                     int nand_chunk, const u8 *data,
  24                                     const struct yaffs_ext_tags *tags)
  25 {
  26         struct yaffs_packed_tags2 pt;
  27         int retval;
  28
  29         int packed_tags_size =
  30             dev->param.no_tags_ecc ? sizeof(pt.t) : sizeof(pt);
  31         void *packed_tags_ptr =
  32             dev->param.no_tags_ecc ? (void *)&pt.t : (void *)&pt;
  33
  34         yaffs_trace(YAFFS_TRACE_MTD,
  35                 "yaffs_tags_marshall_write chunk %d data %p tags %p",
  36                 nand_chunk, data, tags);
  37
  38         /* For yaffs2 writing there must be both data and tags.
  39          * If we're using inband tags, then the tags are stuffed into
  40          * the end of the data buffer.
  41          */
  42         if (!data || !tags)
  43                 BUG();
  44         else if (dev->param.inband_tags) {
  45                 struct yaffs_packed_tags2_tags_only *pt2tp;
  46                 pt2tp =
  47                     (struct yaffs_packed_tags2_tags_only *)(data +
  48                                                         dev->
  49                                                         data_bytes_per_chunk);
  50                 yaffs_pack_tags2_tags_only(dev, pt2tp, tags);
  51         } else {
  52                 yaffs_pack_tags2(dev, &pt, tags, !dev->param.no_tags_ecc);
  53         }
  54
  55         retval = dev->drv.drv_write_chunk_fn(dev, nand_chunk,
  56                         data, dev->param.total_bytes_per_chunk,
  57                         (dev->param.inband_tags) ? NULL : packed_tags_ptr,
  58                         (dev->param.inband_tags) ? 0 : packed_tags_size);
  59
  60         return retval;
  61 }
  62
  63 static int yaffs_tags_marshall_read(struct yaffs_dev *dev,
  64                                    int nand_chunk, u8 *data,
  65                                    struct yaffs_ext_tags *tags)
  66 {
  67         int retval = 0;
  68         int local_data = 0;
  69         u8 spare_buffer[100];
  70         enum yaffs_ecc_result ecc_result;
  71
  72         struct yaffs_packed_tags2 pt;
  73
  74         int packed_tags_size =
  75             dev->param.no_tags_ecc ? sizeof(pt.t) : sizeof(pt);
  76         void *packed_tags_ptr =
  77             dev->param.no_tags_ecc ? (void *)&pt.t : (void *)&pt;
  78
  79         yaffs_trace(YAFFS_TRACE_MTD,
  80                 "yaffs_tags_marshall_read chunk %d data %p tags %p",
  81                 nand_chunk, data, tags);
  82
  83         if (dev->param.inband_tags) {
  84                 if (!data) {
  85                         local_data = 1;
  86                         data = yaffs_get_temp_buffer(dev);
  87                 }
  88         }
  89
  90         if (dev->param.inband_tags || (data && !tags))
  91                 retval = dev->drv.drv_read_chunk_fn(dev, nand_chunk,
  92                                         data, dev->param.total_bytes_per_chunk,
  93                                         NULL, 0,
  94                                         &ecc_result);
  95         else if (tags)
  96                 retval = dev->drv.drv_read_chunk_fn(dev, nand_chunk,
  97                                         data, dev->param.total_bytes_per_chunk,
  98                                         spare_buffer, packed_tags_size,
  99                                         &ecc_result);
 100         else
 101                 BUG();
 102
 103
 104         if (dev->param.inband_tags) {
 105                 if (tags) {
 106                         struct yaffs_packed_tags2_tags_only *pt2tp;
 107                         pt2tp =
 108                                 (struct yaffs_packed_tags2_tags_only *)
 109                                 &data[dev->data_bytes_per_chunk];
 110                         yaffs_unpack_tags2_tags_only(dev, tags, pt2tp);
 111                 }
 112         } else if (tags) {
 113                 memcpy(packed_tags_ptr, spare_buffer, packed_tags_size);
 114                 yaffs_unpack_tags2(dev, tags, &pt, !dev->param.no_tags_ecc);
 115         }
 116
 117         if (local_data)
 118                 yaffs_release_temp_buffer(dev, data);
 119
 120         if (tags && ecc_result == YAFFS_ECC_RESULT_UNFIXED) {
 121                 tags->ecc_result = YAFFS_ECC_RESULT_UNFIXED;
 122                 dev->n_ecc_unfixed++;
 123         }
 124
 125         if (tags && ecc_result == -YAFFS_ECC_RESULT_FIXED) {
 126                 if (tags->ecc_result <= YAFFS_ECC_RESULT_NO_ERROR)
 127                         tags->ecc_result = YAFFS_ECC_RESULT_FIXED;
 128                 dev->n_ecc_fixed++;
 129         }
 130
 131         if (ecc_result < YAFFS_ECC_RESULT_UNFIXED)
 132                 return YAFFS_OK;
 133         else
 134                 return YAFFS_FAIL;
 135 }
 136
 137 static int yaffs_tags_marshall_query_block(struct yaffs_dev *dev, int block_no,
 138                                enum yaffs_block_state *state,
 139                                u32 *seq_number)
 140 {
 141         int retval;
 142
 143         yaffs_trace(YAFFS_TRACE_MTD, "yaffs_tags_marshall_query_block %d",
 144                         block_no);
 145
 146         retval = dev->drv.drv_check_bad_fn(dev, block_no);
 147
 148         if (retval== YAFFS_FAIL) {
 149                 yaffs_trace(YAFFS_TRACE_MTD, "block is bad");
 150
 151                 *state = YAFFS_BLOCK_STATE_DEAD;
 152                 *seq_number = 0;
 153         } else {
 154                 struct yaffs_ext_tags t;
 155
 156                 yaffs_tags_marshall_read(dev,
 157                                     block_no * dev->param.chunks_per_block,
 158                                     NULL, &t);
 159
 160                 if (t.chunk_used) {
 161                         *seq_number = t.seq_number;
 162                         *state = YAFFS_BLOCK_STATE_NEEDS_SCAN;
 163                 } else {
 164                         *seq_number = 0;
 165                         *state = YAFFS_BLOCK_STATE_EMPTY;
 166                 }
 167         }
 168
 169         yaffs_trace(YAFFS_TRACE_MTD,
 170                 "block query returns  seq %d state %d",
 171                 *seq_number, *state);
 172
 173         if (retval == 0)
 174                 return YAFFS_OK;
 175         else
 176                 return YAFFS_FAIL;
 177 }
 178
 179 static int yaffs_tags_marshall_mark_bad(struct yaffs_dev *dev, int block_no)
 180 {
 181         return dev->drv.drv_mark_bad_fn(dev, block_no);
 182
 183 }
 184
 185
 186 void yaffs_tags_marshall_install(struct yaffs_dev *dev)
 187 {
 188         if (!dev->param.is_yaffs2)
 189                 return;
 190
 191         if (!dev->tagger.write_chunk_tags_fn)
 192                 dev->tagger.write_chunk_tags_fn = yaffs_tags_marshall_write;
 193
 194         if (!dev->tagger.read_chunk_tags_fn)
 195                 dev->tagger.read_chunk_tags_fn = yaffs_tags_marshall_read;
 196
 197         if (!dev->tagger.query_block_fn)
 198                 dev->tagger.query_block_fn = yaffs_tags_marshall_query_block;
 199
 200         if (!dev->tagger.mark_bad_fn)
 201                 dev->tagger.mark_bad_fn = yaffs_tags_marshall_mark_bad;
 202
 203 }