drivers/mtd/inftlmount.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * inftlmount.c -- INFTL mount code with extensive checks.
   4  *
   5  * Author: Greg Ungerer (gerg@snapgear.com)
   6  * Copyright © 2002-2003, Greg Ungerer (gerg@snapgear.com)
   7  *
   8  * Based heavily on the nftlmount.c code which is:
   9  * Author: Fabrice Bellard (fabrice.bellard@netgem.com)
  10  * Copyright © 2000 Netgem S.A.
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <asm/errno.h>
  16 #include <asm/io.h>
  17 #include <linux/uaccess.h>
  18 #include <linux/delay.h>
  19 #include <linux/slab.h>
  20 #include <linux/mtd/mtd.h>
  21 #include <linux/mtd/nftl.h>
  22 #include <linux/mtd/inftl.h>
  23
  24 /*
  25  * find_boot_record: Find the INFTL Media Header and its Spare copy which
  26  *      contains the various device information of the INFTL partition and
  27  *      Bad Unit Table. Update the PUtable[] table according to the Bad
  28  *      Unit Table. PUtable[] is used for management of Erase Unit in
  29  *      other routines in inftlcore.c and inftlmount.c.
  30  */
  31 static int find_boot_record(struct INFTLrecord *inftl)
  32 {
  33         struct inftl_unittail h1;
  34         //struct inftl_oob oob;
  35         unsigned int i, block;
  36         u8 buf[SECTORSIZE];
  37         struct INFTLMediaHeader *mh = &inftl->MediaHdr;
  38         struct mtd_info *mtd = inftl->mbd.mtd;
  39         struct INFTLPartition *ip;
  40         size_t retlen;
  41
  42         pr_debug("INFTL: find_boot_record(inftl=%p)\n", inftl);
  43
  44         /*
  45          * Assume logical EraseSize == physical erasesize for starting the
  46          * scan. We'll sort it out later if we find a MediaHeader which says
  47          * otherwise.
  48          */
  49         inftl->EraseSize = inftl->mbd.mtd->erasesize;
  50         inftl->nb_blocks = (u32)inftl->mbd.mtd->size / inftl->EraseSize;
  51
  52         inftl->MediaUnit = BLOCK_NIL;
  53
  54         /* Search for a valid boot record */
  55         for (block = 0; block < inftl->nb_blocks; block++) {
  56                 int ret;
  57
  58                 /*
  59                  * Check for BNAND header first. Then whinge if it's found
  60                  * but later checks fail.
  61                  */
  62                 ret = mtd_read(mtd, block * inftl->EraseSize, SECTORSIZE,
  63                                &retlen, buf);
  64                 /* We ignore ret in case the ECC of the MediaHeader is invalid
  65                    (which is apparently acceptable) */
  66                 if (retlen != SECTORSIZE) {
  67                         static int warncount = 5;
  68
  69                         if (warncount) {
  70                                 printk(KERN_WARNING "INFTL: block read at 0x%x "
  71                                         "of mtd%d failed: %d\n",
  72                                         block * inftl->EraseSize,
  73                                         inftl->mbd.mtd->index, ret);
  74                                 if (!--warncount)
  75                                         printk(KERN_WARNING "INFTL: further "
  76                                                 "failures for this block will "
  77                                                 "not be printed\n");
  78                         }
  79                         continue;
  80                 }
  81
  82                 if (retlen < 6 || memcmp(buf, "BNAND", 6)) {
  83                         /* BNAND\0 not found. Continue */
  84                         continue;
  85                 }
  86
  87                 /* To be safer with BIOS, also use erase mark as discriminant */
  88                 ret = inftl_read_oob(mtd,
  89                                      block * inftl->EraseSize + SECTORSIZE + 8,
  90                                      8, &retlen,(char *)&h1);
  91                 if (ret < 0) {
  92                         printk(KERN_WARNING "INFTL: ANAND header found at "
  93                                 "0x%x in mtd%d, but OOB data read failed "
  94                                 "(err %d)\n", block * inftl->EraseSize,
  95                                 inftl->mbd.mtd->index, ret);
  96                         continue;
  97                 }
  98
  99
 100                 /*
 101                  * This is the first we've seen.
 102                  * Copy the media header structure into place.
 103                  */
 104                 memcpy(mh, buf, sizeof(struct INFTLMediaHeader));
 105
 106                 /* Read the spare media header at offset 4096 */
 107                 mtd_read(mtd, block * inftl->EraseSize + 4096, SECTORSIZE,
 108                          &retlen, buf);
 109                 if (retlen != SECTORSIZE) {
 110                         printk(KERN_WARNING "INFTL: Unable to read spare "
 111                                "Media Header\n");
 112                         return -1;
 113                 }
 114                 /* Check if this one is the same as the first one we found. */
 115                 if (memcmp(mh, buf, sizeof(struct INFTLMediaHeader))) {
 116                         printk(KERN_WARNING "INFTL: Primary and spare Media "
 117                                "Headers disagree.\n");
 118                         return -1;
 119                 }
 120
 121                 mh->NoOfBootImageBlocks = le32_to_cpu(mh->NoOfBootImageBlocks);
 122                 mh->NoOfBinaryPartitions = le32_to_cpu(mh->NoOfBinaryPartitions);
 123                 mh->NoOfBDTLPartitions = le32_to_cpu(mh->NoOfBDTLPartitions);
 124                 mh->BlockMultiplierBits = le32_to_cpu(mh->BlockMultiplierBits);
 125                 mh->FormatFlags = le32_to_cpu(mh->FormatFlags);
 126                 mh->PercentUsed = le32_to_cpu(mh->PercentUsed);
 127
 128                 pr_debug("INFTL: Media Header ->\n"
 129                          "    bootRecordID          = %s\n"
 130                          "    NoOfBootImageBlocks   = %d\n"
 131                          "    NoOfBinaryPartitions  = %d\n"
 132                          "    NoOfBDTLPartitions    = %d\n"
 133                          "    BlockMultiplierBits   = %d\n"
 134                          "    FormatFlgs            = %d\n"
 135                          "    OsakVersion           = 0x%x\n"
 136                          "    PercentUsed           = %d\n",
 137                          mh->bootRecordID, mh->NoOfBootImageBlocks,
 138                          mh->NoOfBinaryPartitions,
 139                          mh->NoOfBDTLPartitions,
 140                          mh->BlockMultiplierBits, mh->FormatFlags,
 141                          mh->OsakVersion, mh->PercentUsed);
 142
 143                 if (mh->NoOfBDTLPartitions == 0) {
 144                         printk(KERN_WARNING "INFTL: Media Header sanity check "
 145                                 "failed: NoOfBDTLPartitions (%d) == 0, "
 146                                 "must be at least 1\n", mh->NoOfBDTLPartitions);
 147                         return -1;
 148                 }
 149
 150                 if ((mh->NoOfBDTLPartitions + mh->NoOfBinaryPartitions) > 4) {
 151                         printk(KERN_WARNING "INFTL: Media Header sanity check "
 152                                 "failed: Total Partitions (%d) > 4, "
 153                                 "BDTL=%d Binary=%d\n", mh->NoOfBDTLPartitions +
 154                                 mh->NoOfBinaryPartitions,
 155                                 mh->NoOfBDTLPartitions,
 156                                 mh->NoOfBinaryPartitions);
 157                         return -1;
 158                 }
 159
 160                 if (mh->BlockMultiplierBits > 1) {
 161                         printk(KERN_WARNING "INFTL: sorry, we don't support "
 162                                 "UnitSizeFactor 0x%02x\n",
 163                                 mh->BlockMultiplierBits);
 164                         return -1;
 165                 } else if (mh->BlockMultiplierBits == 1) {
 166                         printk(KERN_WARNING "INFTL: support for INFTL with "
 167                                 "UnitSizeFactor 0x%02x is experimental\n",
 168                                 mh->BlockMultiplierBits);
 169                         inftl->EraseSize = inftl->mbd.mtd->erasesize <<
 170                                 mh->BlockMultiplierBits;
 171                         inftl->nb_blocks = (u32)inftl->mbd.mtd->size / inftl->EraseSize;
 172                         block >>= mh->BlockMultiplierBits;
 173                 }
 174
 175                 /* Scan the partitions */
 176                 for (i = 0; (i < 4); i++) {
 177                         ip = &mh->Partitions[i];
 178                         ip->virtualUnits = le32_to_cpu(ip->virtualUnits);
 179                         ip->firstUnit = le32_to_cpu(ip->firstUnit);
 180                         ip->lastUnit = le32_to_cpu(ip->lastUnit);
 181                         ip->flags = le32_to_cpu(ip->flags);
 182                         ip->spareUnits = le32_to_cpu(ip->spareUnits);
 183                         ip->Reserved0 = le32_to_cpu(ip->Reserved0);
 184
 185                         pr_debug("    PARTITION[%d] ->\n"
 186                                  "        virtualUnits    = %d\n"
 187                                  "        firstUnit       = %d\n"
 188                                  "        lastUnit        = %d\n"
 189                                  "        flags           = 0x%x\n"
 190                                  "        spareUnits      = %d\n",
 191                                  i, ip->virtualUnits, ip->firstUnit,
 192                                  ip->lastUnit, ip->flags,
 193                                  ip->spareUnits);
 194
 195                         if (ip->Reserved0 != ip->firstUnit) {
 196                                 struct erase_info *instr = &inftl->instr;
 197
 198                                 /*
 199                                  *      Most likely this is using the
 200                                  *      undocumented qiuck mount feature.
 201                                  *      We don't support that, we will need
 202                                  *      to erase the hidden block for full
 203                                  *      compatibility.
 204                                  */
 205                                 instr->addr = ip->Reserved0 * inftl->EraseSize;
 206                                 instr->len = inftl->EraseSize;
 207                                 mtd_erase(mtd, instr);
 208                         }
 209                         if ((ip->lastUnit - ip->firstUnit + 1) < ip->virtualUnits) {
 210                                 printk(KERN_WARNING "INFTL: Media Header "
 211                                         "Partition %d sanity check failed\n"
 212                                         "    firstUnit %d : lastUnit %d  >  "
 213                                         "virtualUnits %d\n", i, ip->lastUnit,
 214                                         ip->firstUnit, ip->Reserved0);
 215                                 return -1;
 216                         }
 217                         if (ip->Reserved1 != 0) {
 218                                 printk(KERN_WARNING "INFTL: Media Header "
 219                                         "Partition %d sanity check failed: "
 220                                         "Reserved1 %d != 0\n",
 221                                         i, ip->Reserved1);
 222                                 return -1;
 223                         }
 224
 225                         if (ip->flags & INFTL_BDTL)
 226                                 break;
 227                 }
 228
 229                 if (i >= 4) {
 230                         printk(KERN_WARNING "INFTL: Media Header Partition "
 231                                 "sanity check failed:\n       No partition "
 232                                 "marked as Disk Partition\n");
 233                         return -1;
 234                 }
 235
 236                 inftl->nb_boot_blocks = ip->firstUnit;
 237                 inftl->numvunits = ip->virtualUnits;
 238                 if (inftl->numvunits > (inftl->nb_blocks -
 239                     inftl->nb_boot_blocks - 2)) {
 240                         printk(KERN_WARNING "INFTL: Media Header sanity check "
 241                                 "failed:\n        numvunits (%d) > nb_blocks "
 242                                 "(%d) - nb_boot_blocks(%d) - 2\n",
 243                                 inftl->numvunits, inftl->nb_blocks,
 244                                 inftl->nb_boot_blocks);
 245                         return -1;
 246                 }
 247
 248                 inftl->mbd.size  = inftl->numvunits *
 249                         (inftl->EraseSize / SECTORSIZE);
 250
 251                 /*
 252                  * Block count is set to last used EUN (we won't need to keep
 253                  * any meta-data past that point).
 254                  */
 255                 inftl->firstEUN = ip->firstUnit;
 256                 inftl->lastEUN = ip->lastUnit;
 257                 inftl->nb_blocks = ip->lastUnit + 1;
 258
 259                 /* Memory alloc */
 260                 inftl->PUtable = kmalloc_array(inftl->nb_blocks, sizeof(u16),
 261                                                GFP_KERNEL);
 262                 if (!inftl->PUtable)
 263                         return -ENOMEM;
 264
 265                 inftl->VUtable = kmalloc_array(inftl->nb_blocks, sizeof(u16),
 266                                                GFP_KERNEL);
 267                 if (!inftl->VUtable) {
 268                         kfree(inftl->PUtable);
 269                         return -ENOMEM;
 270                 }
 271
 272                 /* Mark the blocks before INFTL MediaHeader as reserved */
 273                 for (i = 0; i < inftl->nb_boot_blocks; i++)
 274                         inftl->PUtable[i] = BLOCK_RESERVED;
 275                 /* Mark all remaining blocks as potentially containing data */
 276                 for (; i < inftl->nb_blocks; i++)
 277                         inftl->PUtable[i] = BLOCK_NOTEXPLORED;
 278
 279                 /* Mark this boot record (NFTL MediaHeader) block as reserved */
 280                 inftl->PUtable[block] = BLOCK_RESERVED;
 281
 282                 /* Read Bad Erase Unit Table and modify PUtable[] accordingly */
 283                 for (i = 0; i < inftl->nb_blocks; i++) {
 284                         int physblock;
 285                         /* If any of the physical eraseblocks are bad, don't
 286                            use the unit. */
 287                         for (physblock = 0; physblock < inftl->EraseSize; physblock += inftl->mbd.mtd->erasesize) {
 288                                 if (mtd_block_isbad(inftl->mbd.mtd,
 289                                                     i * inftl->EraseSize + physblock))
 290                                         inftl->PUtable[i] = BLOCK_RESERVED;
 291                         }
 292                 }
 293
 294                 inftl->MediaUnit = block;
 295                 return 0;
 296         }
 297
 298         /* Not found. */
 299         return -1;
 300 }
 301
 302 static int memcmpb(void *a, int c, int n)
 303 {
 304         int i;
 305         for (i = 0; i < n; i++) {
 306                 if (c != ((unsigned char *)a)[i])
 307                         return 1;
 308         }
 309         return 0;
 310 }
 311
 312 /*
 313  * check_free_sector: check if a free sector is actually FREE,
 314  *      i.e. All 0xff in data and oob area.
 315  */
 316 static int check_free_sectors(struct INFTLrecord *inftl, unsigned int address,
 317         int len, int check_oob)
 318 {
 319         struct mtd_info *mtd = inftl->mbd.mtd;
 320         size_t retlen;
 321         int i, ret;
 322         u8 *buf;
 323
 324         buf = kmalloc(SECTORSIZE + mtd->oobsize, GFP_KERNEL);
 325         if (!buf)
 326                 return -ENOMEM;
 327
 328         ret = -1;
 329         for (i = 0; i < len; i += SECTORSIZE) {
 330                 if (mtd_read(mtd, address, SECTORSIZE, &retlen, buf))
 331                         goto out;
 332                 if (memcmpb(buf, 0xff, SECTORSIZE) != 0)
 333                         goto out;
 334
 335                 if (check_oob) {
 336                         if(inftl_read_oob(mtd, address, mtd->oobsize,
 337                                           &retlen, &buf[SECTORSIZE]) < 0)
 338                                 goto out;
 339                         if (memcmpb(buf + SECTORSIZE, 0xff, mtd->oobsize) != 0)
 340                                 goto out;
 341                 }
 342                 address += SECTORSIZE;
 343         }
 344
 345         ret = 0;
 346
 347 out:
 348         kfree(buf);
 349         return ret;
 350 }
 351
 352 /*
 353  * INFTL_format: format a Erase Unit by erasing ALL Erase Zones in the Erase
 354  *               Unit and Update INFTL metadata. Each erase operation is
 355  *               checked with check_free_sectors.
 356  *
 357  * Return: 0 when succeed, -1 on error.
 358  *
 359  * ToDo: 1. Is it necessary to check_free_sector after erasing ??
 360  */
 361 int INFTL_formatblock(struct INFTLrecord *inftl, int block)
 362 {
 363         size_t retlen;
 364         struct inftl_unittail uci;
 365         struct erase_info *instr = &inftl->instr;
 366         struct mtd_info *mtd = inftl->mbd.mtd;
 367         int physblock;
 368
 369         pr_debug("INFTL: INFTL_formatblock(inftl=%p,block=%d)\n", inftl, block);
 370
 371         memset(instr, 0, sizeof(struct erase_info));
 372
 373         /* FIXME: Shouldn't we be setting the 'discarded' flag to zero
 374            _first_? */
 375
 376         /* Use async erase interface, test return code */
 377         instr->addr = block * inftl->EraseSize;
 378         instr->len = inftl->mbd.mtd->erasesize;
 379         /* Erase one physical eraseblock at a time, even though the NAND api
 380            allows us to group them.  This way we if we have a failure, we can
 381            mark only the failed block in the bbt. */
 382         for (physblock = 0; physblock < inftl->EraseSize;
 383              physblock += instr->len, instr->addr += instr->len) {
 384                 int ret;
 385
 386                 ret = mtd_erase(inftl->mbd.mtd, instr);
 387                 if (ret) {
 388                         printk(KERN_WARNING "INFTL: error while formatting block %d\n",
 389                                 block);
 390                         goto fail;
 391                 }
 392
 393                 /*
 394                  * Check the "freeness" of Erase Unit before updating metadata.
 395                  * FixMe: is this check really necessary? Since we have check
 396                  * the return code after the erase operation.
 397                  */
 398                 if (check_free_sectors(inftl, instr->addr, instr->len, 1) != 0)
 399                         goto fail;
 400         }
 401
 402         uci.EraseMark = cpu_to_le16(ERASE_MARK);
 403         uci.EraseMark1 = cpu_to_le16(ERASE_MARK);
 404         uci.Reserved[0] = 0;
 405         uci.Reserved[1] = 0;
 406         uci.Reserved[2] = 0;
 407         uci.Reserved[3] = 0;
 408         instr->addr = block * inftl->EraseSize + SECTORSIZE * 2;
 409         if (inftl_write_oob(mtd, instr->addr + 8, 8, &retlen, (char *)&uci) < 0)
 410                 goto fail;
 411         return 0;
 412 fail:
 413         /* could not format, update the bad block table (caller is responsible
 414            for setting the PUtable to BLOCK_RESERVED on failure) */
 415         mtd_block_markbad(inftl->mbd.mtd, instr->addr);
 416         return -1;
 417 }
 418
 419 /*
 420  * format_chain: Format an invalid Virtual Unit chain. It frees all the Erase
 421  *      Units in a Virtual Unit Chain, i.e. all the units are disconnected.
 422  *
 423  *      Since the chain is invalid then we will have to erase it from its
 424  *      head (normally for INFTL we go from the oldest). But if it has a
 425  *      loop then there is no oldest...
 426  */
 427 static void format_chain(struct INFTLrecord *inftl, unsigned int first_block)
 428 {
 429         unsigned int block = first_block, block1;
 430
 431         printk(KERN_WARNING "INFTL: formatting chain at block %d\n",
 432                 first_block);
 433
 434         for (;;) {
 435                 block1 = inftl->PUtable[block];
 436
 437                 printk(KERN_WARNING "INFTL: formatting block %d\n", block);
 438                 if (INFTL_formatblock(inftl, block) < 0) {
 439                         /*
 440                          * Cannot format !!!! Mark it as Bad Unit,
 441                          */
 442                         inftl->PUtable[block] = BLOCK_RESERVED;
 443                 } else {
 444                         inftl->PUtable[block] = BLOCK_FREE;
 445                 }
 446
 447                 /* Goto next block on the chain */
 448                 block = block1;
 449
 450                 if (block == BLOCK_NIL || block >= inftl->lastEUN)
 451                         break;
 452         }
 453 }
 454
 455 void INFTL_dumptables(struct INFTLrecord *s)
 456 {
 457         int i;
 458
 459         pr_debug("-------------------------------------------"
 460                 "----------------------------------\n");
 461
 462         pr_debug("VUtable[%d] ->", s->nb_blocks);
 463         for (i = 0; i < s->nb_blocks; i++) {
 464                 if ((i % 8) == 0)
 465                         pr_debug("\n%04x: ", i);
 466                 pr_debug("%04x ", s->VUtable[i]);
 467         }
 468
 469         pr_debug("\n-------------------------------------------"
 470                 "----------------------------------\n");
 471
 472         pr_debug("PUtable[%d-%d=%d] ->", s->firstEUN, s->lastEUN, s->nb_blocks);
 473         for (i = 0; i <= s->lastEUN; i++) {
 474                 if ((i % 8) == 0)
 475                         pr_debug("\n%04x: ", i);
 476                 pr_debug("%04x ", s->PUtable[i]);
 477         }
 478
 479         pr_debug("\n-------------------------------------------"
 480                 "----------------------------------\n");
 481
 482         pr_debug("INFTL ->\n"
 483                 "  EraseSize       = %d\n"
 484                 "  h/s/c           = %d/%d/%d\n"
 485                 "  numvunits       = %d\n"
 486                 "  firstEUN        = %d\n"
 487                 "  lastEUN         = %d\n"
 488                 "  numfreeEUNs     = %d\n"
 489                 "  LastFreeEUN     = %d\n"
 490                 "  nb_blocks       = %d\n"
 491                 "  nb_boot_blocks  = %d",
 492                 s->EraseSize, s->heads, s->sectors, s->cylinders,
 493                 s->numvunits, s->firstEUN, s->lastEUN, s->numfreeEUNs,
 494                 s->LastFreeEUN, s->nb_blocks, s->nb_boot_blocks);
 495
 496         pr_debug("\n-------------------------------------------"
 497                 "----------------------------------\n");
 498 }
 499
 500 void INFTL_dumpVUchains(struct INFTLrecord *s)
 501 {
 502         int logical, block, i;
 503
 504         pr_debug("-------------------------------------------"
 505                 "----------------------------------\n");
 506
 507         pr_debug("INFTL Virtual Unit Chains:\n");
 508         for (logical = 0; logical < s->nb_blocks; logical++) {
 509                 block = s->VUtable[logical];
 510                 if (block >= s->nb_blocks)
 511                         continue;
 512                 pr_debug("  LOGICAL %d --> %d ", logical, block);
 513                 for (i = 0; i < s->nb_blocks; i++) {
 514                         if (s->PUtable[block] == BLOCK_NIL)
 515                                 break;
 516                         block = s->PUtable[block];
 517                         pr_debug("%d ", block);
 518                 }
 519                 pr_debug("\n");
 520         }
 521
 522         pr_debug("-------------------------------------------"
 523                 "----------------------------------\n");
 524 }
 525
 526 int INFTL_mount(struct INFTLrecord *s)
 527 {
 528         struct mtd_info *mtd = s->mbd.mtd;
 529         unsigned int block, first_block, prev_block, last_block;
 530         unsigned int first_logical_block, logical_block, erase_mark;
 531         int chain_length, do_format_chain;
 532         struct inftl_unithead1 h0;
 533         struct inftl_unittail h1;
 534         size_t retlen;
 535         int i;
 536         u8 *ANACtable, ANAC;
 537
 538         pr_debug("INFTL: INFTL_mount(inftl=%p)\n", s);
 539
 540         /* Search for INFTL MediaHeader and Spare INFTL Media Header */
 541         if (find_boot_record(s) < 0) {
 542                 printk(KERN_WARNING "INFTL: could not find valid boot record?\n");
 543                 return -ENXIO;
 544         }
 545
 546         /* Init the logical to physical table */
 547         for (i = 0; i < s->nb_blocks; i++)
 548                 s->VUtable[i] = BLOCK_NIL;
 549
 550         logical_block = block = BLOCK_NIL;
 551
 552         /* Temporary buffer to store ANAC numbers. */
 553         ANACtable = kcalloc(s->nb_blocks, sizeof(u8), GFP_KERNEL);
 554         if (!ANACtable)
 555                 return -ENOMEM;
 556
 557         /*
 558          * First pass is to explore each physical unit, and construct the
 559          * virtual chains that exist (newest physical unit goes into VUtable).
 560          * Any block that is in any way invalid will be left in the
 561          * NOTEXPLORED state. Then at the end we will try to format it and
 562          * mark it as free.
 563          */
 564         pr_debug("INFTL: pass 1, explore each unit\n");
 565         for (first_block = s->firstEUN; first_block <= s->lastEUN; first_block++) {
 566                 if (s->PUtable[first_block] != BLOCK_NOTEXPLORED)
 567                         continue;
 568
 569                 do_format_chain = 0;
 570                 first_logical_block = BLOCK_NIL;
 571                 last_block = BLOCK_NIL;
 572                 block = first_block;
 573
 574                 for (chain_length = 0; ; chain_length++) {
 575
 576                         if ((chain_length == 0) &&
 577                             (s->PUtable[block] != BLOCK_NOTEXPLORED)) {
 578                                 /* Nothing to do here, onto next block */
 579                                 break;
 580                         }
 581
 582                         if (inftl_read_oob(mtd, block * s->EraseSize + 8,
 583                                            8, &retlen, (char *)&h0) < 0 ||
 584                             inftl_read_oob(mtd, block * s->EraseSize +
 585                                            2 * SECTORSIZE + 8, 8, &retlen,
 586                                            (char *)&h1) < 0) {
 587                                 /* Should never happen? */
 588                                 do_format_chain++;
 589                                 break;
 590                         }
 591
 592                         logical_block = le16_to_cpu(h0.virtualUnitNo);
 593                         prev_block = le16_to_cpu(h0.prevUnitNo);
 594                         erase_mark = le16_to_cpu((h1.EraseMark | h1.EraseMark1));
 595                         ANACtable[block] = h0.ANAC;
 596
 597                         /* Previous block is relative to start of Partition */
 598                         if (prev_block < s->nb_blocks)
 599                                 prev_block += s->firstEUN;
 600
 601                         /* Already explored partial chain? */
 602                         if (s->PUtable[block] != BLOCK_NOTEXPLORED) {
 603                                 /* Check if chain for this logical */
 604                                 if (logical_block == first_logical_block) {
 605                                         if (last_block != BLOCK_NIL)
 606                                                 s->PUtable[last_block] = block;
 607                                 }
 608                                 break;
 609                         }
 610
 611                         /* Check for invalid block */
 612                         if (erase_mark != ERASE_MARK) {
 613                                 printk(KERN_WARNING "INFTL: corrupt block %d "
 614                                         "in chain %d, chain length %d, erase "
 615                                         "mark 0x%x?\n", block, first_block,
 616                                         chain_length, erase_mark);
 617                                 /*
 618                                  * Assume end of chain, probably incomplete
 619                                  * fold/erase...
 620                                  */
 621                                 if (chain_length == 0)
 622                                         do_format_chain++;
 623                                 break;
 624                         }
 625
 626                         /* Check for it being free already then... */
 627                         if ((logical_block == BLOCK_FREE) ||
 628                             (logical_block == BLOCK_NIL)) {
 629                                 s->PUtable[block] = BLOCK_FREE;
 630                                 break;
 631                         }
 632
 633                         /* Sanity checks on block numbers */
 634                         if ((logical_block >= s->nb_blocks) ||
 635                             ((prev_block >= s->nb_blocks) &&
 636                              (prev_block != BLOCK_NIL))) {
 637                                 if (chain_length > 0) {
 638                                         printk(KERN_WARNING "INFTL: corrupt "
 639                                                 "block %d in chain %d?\n",
 640                                                 block, first_block);
 641                                         do_format_chain++;
 642                                 }
 643                                 break;
 644                         }
 645
 646                         if (first_logical_block == BLOCK_NIL) {
 647                                 first_logical_block = logical_block;
 648                         } else {
 649                                 if (first_logical_block != logical_block) {
 650                                         /* Normal for folded chain... */
 651                                         break;
 652                                 }
 653                         }
 654
 655                         /*
 656                          * Current block is valid, so if we followed a virtual
 657                          * chain to get here then we can set the previous
 658                          * block pointer in our PUtable now. Then move onto
 659                          * the previous block in the chain.
 660                          */
 661                         s->PUtable[block] = BLOCK_NIL;
 662                         if (last_block != BLOCK_NIL)
 663                                 s->PUtable[last_block] = block;
 664                         last_block = block;
 665                         block = prev_block;
 666
 667                         /* Check for end of chain */
 668                         if (block == BLOCK_NIL)
 669                                 break;
 670
 671                         /* Validate next block before following it... */
 672                         if (block > s->lastEUN) {
 673                                 printk(KERN_WARNING "INFTL: invalid previous "
 674                                         "block %d in chain %d?\n", block,
 675                                         first_block);
 676                                 do_format_chain++;
 677                                 break;
 678                         }
 679                 }
 680
 681                 if (do_format_chain) {
 682                         format_chain(s, first_block);
 683                         continue;
 684                 }
 685
 686                 /*
 687                  * Looks like a valid chain then. It may not really be the
 688                  * newest block in the chain, but it is the newest we have
 689                  * found so far. We might update it in later iterations of
 690                  * this loop if we find something newer.
 691                  */
 692                 s->VUtable[first_logical_block] = first_block;
 693                 logical_block = BLOCK_NIL;
 694         }
 695
 696         INFTL_dumptables(s);
 697
 698         /*
 699          * Second pass, check for infinite loops in chains. These are
 700          * possible because we don't update the previous pointers when
 701          * we fold chains. No big deal, just fix them up in PUtable.
 702          */
 703         pr_debug("INFTL: pass 2, validate virtual chains\n");
 704         for (logical_block = 0; logical_block < s->numvunits; logical_block++) {
 705                 block = s->VUtable[logical_block];
 706                 last_block = BLOCK_NIL;
 707
 708                 /* Check for free/reserved/nil */
 709                 if (block >= BLOCK_RESERVED)
 710                         continue;
 711
 712                 ANAC = ANACtable[block];
 713                 for (i = 0; i < s->numvunits; i++) {
 714                         if (s->PUtable[block] == BLOCK_NIL)
 715                                 break;
 716                         if (s->PUtable[block] > s->lastEUN) {
 717                                 printk(KERN_WARNING "INFTL: invalid prev %d, "
 718                                         "in virtual chain %d\n",
 719                                         s->PUtable[block], logical_block);
 720                                 s->PUtable[block] = BLOCK_NIL;
 721
 722                         }
 723                         if (ANACtable[block] != ANAC) {
 724                                 /*
 725                                  * Chain must point back to itself. This is ok,
 726                                  * but we will need adjust the tables with this
 727                                  * newest block and oldest block.
 728                                  */
 729                                 s->VUtable[logical_block] = block;
 730                                 s->PUtable[last_block] = BLOCK_NIL;
 731                                 break;
 732                         }
 733
 734                         ANAC--;
 735                         last_block = block;
 736                         block = s->PUtable[block];
 737                 }
 738
 739                 if (i >= s->nb_blocks) {
 740                         /*
 741                          * Uhoo, infinite chain with valid ANACS!
 742                          * Format whole chain...
 743                          */
 744                         format_chain(s, first_block);
 745                 }
 746         }
 747
 748         INFTL_dumptables(s);
 749         INFTL_dumpVUchains(s);
 750
 751         /*
 752          * Third pass, format unreferenced blocks and init free block count.
 753          */
 754         s->numfreeEUNs = 0;
 755         s->LastFreeEUN = BLOCK_NIL;
 756
 757         pr_debug("INFTL: pass 3, format unused blocks\n");
 758         for (block = s->firstEUN; block <= s->lastEUN; block++) {
 759                 if (s->PUtable[block] == BLOCK_NOTEXPLORED) {
 760                         printk("INFTL: unreferenced block %d, formatting it\n",
 761                                 block);
 762                         if (INFTL_formatblock(s, block) < 0)
 763                                 s->PUtable[block] = BLOCK_RESERVED;
 764                         else
 765                                 s->PUtable[block] = BLOCK_FREE;
 766                 }
 767                 if (s->PUtable[block] == BLOCK_FREE) {
 768                         s->numfreeEUNs++;
 769                         if (s->LastFreeEUN == BLOCK_NIL)
 770                                 s->LastFreeEUN = block;
 771                 }
 772         }
 773
 774         kfree(ANACtable);
 775         return 0;
 776 }