target/linux/generic/patches-3.18/502-yaffs-fix-compat-tags-handling.patch

   1 Subject: yaffs: fix compat tags handling
   2
   3 Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
   4 ---
   5 --- a/fs/yaffs2/yaffs_tagscompat.c
   6 +++ b/fs/yaffs2/yaffs_tagscompat.c
   7 @@ -17,7 +17,9 @@
   8  #include "yaffs_getblockinfo.h"
   9  #include "yaffs_trace.h"
  10
  11 +#if 0
  12  static void yaffs_handle_rd_data_error(struct yaffs_dev *dev, int nand_chunk);
  13 +#endif
  14
  15
  16  /********** Tags ECC calculations  *********/
  17 @@ -71,6 +73,7 @@ int yaffs_check_tags_ecc(struct yaffs_ta
  18         return 0;
  19  }
  20
  21 +#if 0
  22  /********** Tags **********/
  23
  24  static void yaffs_load_tags_to_spare(struct yaffs_spare *spare_ptr,
  25 @@ -379,3 +382,214 @@ void yaffs_tags_compat_install(struct ya
  26         if(!dev->tagger.mark_bad_fn)
  27                 dev->tagger.mark_bad_fn = yaffs_tags_compat_mark_bad;
  28  }
  29 +#else
  30 +
  31 +#include "yaffs_packedtags1.h"
  32 +
  33 +static int yaffs_tags_compat_write(struct yaffs_dev *dev,
  34 +                                  int nand_chunk,
  35 +                                  const u8 *data,
  36 +                                  const struct yaffs_ext_tags *tags)
  37 +{
  38 +       struct yaffs_packed_tags1 pt1;
  39 +       u8 tag_buf[9];
  40 +       int retval;
  41 +
  42 +       /* we assume that yaffs_packed_tags1 and yaffs_tags are compatible */
  43 +       compile_time_assertion(sizeof(struct yaffs_packed_tags1) == 12);
  44 +       compile_time_assertion(sizeof(struct yaffs_tags) == 8);
  45 +
  46 +       yaffs_pack_tags1(&pt1, tags);
  47 +       yaffs_calc_tags_ecc((struct yaffs_tags *)&pt1);
  48 +
  49 +       /* When deleting a chunk, the upper layer provides only skeletal
  50 +        * tags, one with is_deleted set.  However, we need to update the
  51 +        * tags, not erase them completely.  So we use the NAND write property
  52 +        * that only zeroed-bits stick and set tag bytes to all-ones and
  53 +        * zero just the (not) deleted bit.
  54 +        */
  55 +       if (!dev->param.tags_9bytes) {
  56 +               if (tags->is_deleted) {
  57 +                       memset(&pt1, 0xff, 8);
  58 +                       /* clear delete status bit to indicate deleted */
  59 +                       pt1.deleted = 0;
  60 +               }
  61 +               memcpy(tag_buf, &pt1, 8);
  62 +       } else {
  63 +               if (tags->is_deleted) {
  64 +                       memset(tag_buf, 0xff, 8);
  65 +                       tag_buf[8] = 0;
  66 +               } else {
  67 +                       memcpy(tag_buf, &pt1, 8);
  68 +                       tag_buf[8] = 0xff;
  69 +               }
  70 +       }
  71 +
  72 +       retval = dev->drv.drv_write_chunk_fn(dev, nand_chunk,
  73 +                       data,
  74 +                       (data) ? dev->data_bytes_per_chunk : 0,
  75 +                       tag_buf,
  76 +                       (dev->param.tags_9bytes) ? 9 : 8);
  77 +
  78 +       return retval;
  79 +}
  80 +
  81 +/* Return with empty extended tags but add ecc_result.
  82 + */
  83 +static int return_empty_tags(struct yaffs_ext_tags *tags,
  84 +                            enum yaffs_ecc_result ecc_result,
  85 +                            int retval)
  86 +{
  87 +       if (tags) {
  88 +               memset(tags, 0, sizeof(*tags));
  89 +               tags->ecc_result = ecc_result;
  90 +       }
  91 +
  92 +       return retval;
  93 +}
  94 +
  95 +static int yaffs_tags_compat_read(struct yaffs_dev *dev,
  96 +                                 int nand_chunk,
  97 +                                 u8 *data,
  98 +                                 struct yaffs_ext_tags *tags)
  99 +{
 100 +       struct yaffs_packed_tags1 pt1;
 101 +       enum yaffs_ecc_result ecc_result;
 102 +       int retval;
 103 +       int deleted;
 104 +       u8 tag_buf[9];
 105 +
 106 +       retval = dev->drv.drv_read_chunk_fn(dev, nand_chunk,
 107 +                       data, dev->param.total_bytes_per_chunk,
 108 +                       tag_buf,
 109 +                       (dev->param.tags_9bytes) ? 9 : 8,
 110 +                       &ecc_result);
 111 +
 112 +       switch (ecc_result) {
 113 +       case YAFFS_ECC_RESULT_NO_ERROR:
 114 +       case YAFFS_ECC_RESULT_FIXED:
 115 +               break;
 116 +
 117 +       case YAFFS_ECC_RESULT_UNFIXED:
 118 +       default:
 119 +               return_empty_tags(tags, YAFFS_ECC_RESULT_UNFIXED, 0);
 120 +               tags->block_bad = dev->drv.drv_check_bad_fn(dev, nand_chunk);
 121 +               return YAFFS_FAIL;
 122 +       }
 123 +
 124 +       /* Check for a blank/erased chunk. */
 125 +       if (yaffs_check_ff(tag_buf, 8)) {
 126 +               /* when blank, upper layers want ecc_result to be <= NO_ERROR */
 127 +               return return_empty_tags(tags, YAFFS_ECC_RESULT_NO_ERROR,
 128 +                                        YAFFS_OK);
 129 +       }
 130 +
 131 +       memcpy(&pt1, tag_buf, 8);
 132 +
 133 +       if (!dev->param.tags_9bytes) {
 134 +               /* Read deleted status (bit) then return it to it's non-deleted
 135 +                * state before performing tags mini-ECC check. pt1.deleted is
 136 +                * inverted.
 137 +                */
 138 +               deleted = !pt1.deleted;
 139 +               pt1.deleted = 1;
 140 +       } else {
 141 +               deleted = (hweight8(tag_buf[8]) < 7) ? 1 : 0;
 142 +       }
 143 +
 144 +       /* Check the packed tags mini-ECC and correct if necessary/possible. */
 145 +       retval = yaffs_check_tags_ecc((struct yaffs_tags *)&pt1);
 146 +       switch (retval) {
 147 +       case 0:
 148 +               /* no tags error, use MTD result */
 149 +               break;
 150 +       case 1:
 151 +               /* recovered tags-ECC error */
 152 +               dev->n_tags_ecc_fixed++;
 153 +               if (ecc_result == YAFFS_ECC_RESULT_NO_ERROR)
 154 +                       ecc_result = YAFFS_ECC_RESULT_FIXED;
 155 +               break;
 156 +       default:
 157 +               /* unrecovered tags-ECC error */
 158 +               dev->n_tags_ecc_unfixed++;
 159 +               return return_empty_tags(tags, YAFFS_ECC_RESULT_UNFIXED,
 160 +                                        YAFFS_FAIL);
 161 +       }
 162 +
 163 +       /* Unpack the tags to extended form and set ECC result.
 164 +        * [set should_be_ff just to keep yaffs_unpack_tags1 happy]
 165 +        */
 166 +       pt1.should_be_ff = 0xffffffff;
 167 +       yaffs_unpack_tags1(tags, &pt1);
 168 +       tags->ecc_result = ecc_result;
 169 +
 170 +       /* Set deleted state */
 171 +       tags->is_deleted = deleted;
 172 +       return YAFFS_OK;
 173 +}
 174 +
 175 +static int yaffs_tags_compat_mark_bad(struct yaffs_dev *dev, int block_no)
 176 +{
 177 +       return dev->drv.drv_mark_bad_fn(dev, block_no);
 178 +}
 179 +
 180 +static int yaffs_tags_compat_query_block(struct yaffs_dev *dev,
 181 +                                        int block_no,
 182 +                                        enum yaffs_block_state *state,
 183 +                                        u32 *seq_number)
 184 +{
 185 +       struct yaffs_ext_tags tags;
 186 +       int retval;
 187 +
 188 +       yaffs_trace(YAFFS_TRACE_MTD, "%s %d", __func__, block_no);
 189 +
 190 +       *seq_number = 0;
 191 +
 192 +       retval = dev->drv.drv_check_bad_fn(dev, block_no);
 193 +       if (retval == YAFFS_FAIL) {
 194 +               *state = YAFFS_BLOCK_STATE_DEAD;
 195 +               goto out;
 196 +       }
 197 +
 198 +       yaffs_tags_compat_read(dev, block_no * dev->param.chunks_per_block,
 199 +                              NULL, &tags);
 200 +
 201 +       if (tags.ecc_result != YAFFS_ECC_RESULT_NO_ERROR) {
 202 +               yaffs_trace(YAFFS_TRACE_MTD, "block %d is marked bad",
 203 +                           block_no);
 204 +               *state = YAFFS_BLOCK_STATE_NEEDS_SCAN;
 205 +       } else if (tags.chunk_used) {
 206 +               *seq_number = tags.seq_number;
 207 +               *state = YAFFS_BLOCK_STATE_NEEDS_SCAN;
 208 +       } else {
 209 +               *state = YAFFS_BLOCK_STATE_EMPTY;
 210 +       }
 211 +
 212 +       retval = YAFFS_OK;
 213 +
 214 +out:
 215 +       yaffs_trace(YAFFS_TRACE_MTD,
 216 +                   "block query returns seq %u state %d",
 217 +                   *seq_number, *state);
 218 +
 219 +       return retval;
 220 +}
 221 +
 222 +void yaffs_tags_compat_install(struct yaffs_dev *dev)
 223 +{
 224 +       if (dev->param.is_yaffs2)
 225 +               return;
 226 +
 227 +       if (!dev->tagger.write_chunk_tags_fn)
 228 +               dev->tagger.write_chunk_tags_fn = yaffs_tags_compat_write;
 229 +
 230 +       if (!dev->tagger.read_chunk_tags_fn)
 231 +               dev->tagger.read_chunk_tags_fn = yaffs_tags_compat_read;
 232 +
 233 +       if (!dev->tagger.query_block_fn)
 234 +               dev->tagger.query_block_fn = yaffs_tags_compat_query_block;
 235 +
 236 +       if (!dev->tagger.mark_bad_fn)
 237 +               dev->tagger.mark_bad_fn = yaffs_tags_compat_mark_bad;
 238 +}
 239 +#endif