drivers/mtd/inftlmount.c

   1 /*
   2  * inftlmount.c -- INFTL mount code with extensive checks.
   3  *
   4  * Author: Greg Ungerer (gerg@snapgear.com)
   5  * Copyright © 2002-2003, Greg Ungerer (gerg@snapgear.com)
   6  *
   7  * Based heavily on the nftlmount.c code which is:
   8  * Author: Fabrice Bellard (fabrice.bellard@netgem.com)
   9  * Copyright © 2000 Netgem S.A.
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  24  */
  25
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28 #include <asm/errno.h>
  29 #include <asm/io.h>
  30 #include <linux/uaccess.h>
  31 #include <linux/delay.h>
  32 #include <linux/slab.h>
  33 #include <linux/mtd/mtd.h>
  34 #include <linux/mtd/nftl.h>
  35 #include <linux/mtd/inftl.h>
  36
  37 /*
  38  * find_boot_record: Find the INFTL Media Header and its Spare copy which
  39  *      contains the various device information of the INFTL partition and
  40  *      Bad Unit Table. Update the PUtable[] table according to the Bad
  41  *      Unit Table. PUtable[] is used for management of Erase Unit in
  42  *      other routines in inftlcore.c and inftlmount.c.
  43  */
  44 static int find_boot_record(struct INFTLrecord *inftl)
  45 {
  46         struct inftl_unittail h1;
  47         //struct inftl_oob oob;
  48         unsigned int i, block;
  49         u8 buf[SECTORSIZE];
  50         struct INFTLMediaHeader *mh = &inftl->MediaHdr;
  51         struct mtd_info *mtd = inftl->mbd.mtd;
  52         struct INFTLPartition *ip;
  53         size_t retlen;
  54
  55         pr_debug("INFTL: find_boot_record(inftl=%p)\n", inftl);
  56
  57         /*
  58          * Assume logical EraseSize == physical erasesize for starting the
  59          * scan. We'll sort it out later if we find a MediaHeader which says
  60          * otherwise.
  61          */
  62         inftl->EraseSize = inftl->mbd.mtd->erasesize;
  63         inftl->nb_blocks = (u32)inftl->mbd.mtd->size / inftl->EraseSize;
  64
  65         inftl->MediaUnit = BLOCK_NIL;
  66
  67         /* Search for a valid boot record */
  68         for (block = 0; block < inftl->nb_blocks; block++) {
  69                 int ret;
  70
  71                 /*
  72                  * Check for BNAND header first. Then whinge if it's found
  73                  * but later checks fail.
  74                  */
  75                 ret = mtd_read(mtd, block * inftl->EraseSize, SECTORSIZE,
  76                                &retlen, buf);
  77                 /* We ignore ret in case the ECC of the MediaHeader is invalid
  78                    (which is apparently acceptable) */
  79                 if (retlen != SECTORSIZE) {
  80                         static int warncount = 5;
  81
  82                         if (warncount) {
  83                                 printk(KERN_WARNING "INFTL: block read at 0x%x "
  84                                         "of mtd%d failed: %d\n",
  85                                         block * inftl->EraseSize,
  86                                         inftl->mbd.mtd->index, ret);
  87                                 if (!--warncount)
  88                                         printk(KERN_WARNING "INFTL: further "
  89                                                 "failures for this block will "
  90                                                 "not be printed\n");
  91                         }
  92                         continue;
  93                 }
  94
  95                 if (retlen < 6 || memcmp(buf, "BNAND", 6)) {
  96                         /* BNAND\0 not found. Continue */
  97                         continue;
  98                 }
  99
 100                 /* To be safer with BIOS, also use erase mark as discriminant */
 101                 ret = inftl_read_oob(mtd,
 102                                      block * inftl->EraseSize + SECTORSIZE + 8,
 103                                      8, &retlen,(char *)&h1);
 104                 if (ret < 0) {
 105                         printk(KERN_WARNING "INFTL: ANAND header found at "
 106                                 "0x%x in mtd%d, but OOB data read failed "
 107                                 "(err %d)\n", block * inftl->EraseSize,
 108                                 inftl->mbd.mtd->index, ret);
 109                         continue;
 110                 }
 111
 112
 113                 /*
 114                  * This is the first we've seen.
 115                  * Copy the media header structure into place.
 116                  */
 117                 memcpy(mh, buf, sizeof(struct INFTLMediaHeader));
 118
 119                 /* Read the spare media header at offset 4096 */
 120                 mtd_read(mtd, block * inftl->EraseSize + 4096, SECTORSIZE,
 121                          &retlen, buf);
 122                 if (retlen != SECTORSIZE) {
 123                         printk(KERN_WARNING "INFTL: Unable to read spare "
 124                                "Media Header\n");
 125                         return -1;
 126                 }
 127                 /* Check if this one is the same as the first one we found. */
 128                 if (memcmp(mh, buf, sizeof(struct INFTLMediaHeader))) {
 129                         printk(KERN_WARNING "INFTL: Primary and spare Media "
 130                                "Headers disagree.\n");
 131                         return -1;
 132                 }
 133
 134                 mh->NoOfBootImageBlocks = le32_to_cpu(mh->NoOfBootImageBlocks);
 135                 mh->NoOfBinaryPartitions = le32_to_cpu(mh->NoOfBinaryPartitions);
 136                 mh->NoOfBDTLPartitions = le32_to_cpu(mh->NoOfBDTLPartitions);
 137                 mh->BlockMultiplierBits = le32_to_cpu(mh->BlockMultiplierBits);
 138                 mh->FormatFlags = le32_to_cpu(mh->FormatFlags);
 139                 mh->PercentUsed = le32_to_cpu(mh->PercentUsed);
 140
 141                 pr_debug("INFTL: Media Header ->\n"
 142                          "    bootRecordID          = %s\n"
 143                          "    NoOfBootImageBlocks   = %d\n"
 144                          "    NoOfBinaryPartitions  = %d\n"
 145                          "    NoOfBDTLPartitions    = %d\n"
 146                          "    BlockMultiplerBits    = %d\n"
 147                          "    FormatFlgs            = %d\n"
 148                          "    OsakVersion           = 0x%x\n"
 149                          "    PercentUsed           = %d\n",
 150                          mh->bootRecordID, mh->NoOfBootImageBlocks,
 151                          mh->NoOfBinaryPartitions,
 152                          mh->NoOfBDTLPartitions,
 153                          mh->BlockMultiplierBits, mh->FormatFlags,
 154                          mh->OsakVersion, mh->PercentUsed);
 155
 156                 if (mh->NoOfBDTLPartitions == 0) {
 157                         printk(KERN_WARNING "INFTL: Media Header sanity check "
 158                                 "failed: NoOfBDTLPartitions (%d) == 0, "
 159                                 "must be at least 1\n", mh->NoOfBDTLPartitions);
 160                         return -1;
 161                 }
 162
 163                 if ((mh->NoOfBDTLPartitions + mh->NoOfBinaryPartitions) > 4) {
 164                         printk(KERN_WARNING "INFTL: Media Header sanity check "
 165                                 "failed: Total Partitions (%d) > 4, "
 166                                 "BDTL=%d Binary=%d\n", mh->NoOfBDTLPartitions +
 167                                 mh->NoOfBinaryPartitions,
 168                                 mh->NoOfBDTLPartitions,
 169                                 mh->NoOfBinaryPartitions);
 170                         return -1;
 171                 }
 172
 173                 if (mh->BlockMultiplierBits > 1) {
 174                         printk(KERN_WARNING "INFTL: sorry, we don't support "
 175                                 "UnitSizeFactor 0x%02x\n",
 176                                 mh->BlockMultiplierBits);
 177                         return -1;
 178                 } else if (mh->BlockMultiplierBits == 1) {
 179                         printk(KERN_WARNING "INFTL: support for INFTL with "
 180                                 "UnitSizeFactor 0x%02x is experimental\n",
 181                                 mh->BlockMultiplierBits);
 182                         inftl->EraseSize = inftl->mbd.mtd->erasesize <<
 183                                 mh->BlockMultiplierBits;
 184                         inftl->nb_blocks = (u32)inftl->mbd.mtd->size / inftl->EraseSize;
 185                         block >>= mh->BlockMultiplierBits;
 186                 }
 187
 188                 /* Scan the partitions */
 189                 for (i = 0; (i < 4); i++) {
 190                         ip = &mh->Partitions[i];
 191                         ip->virtualUnits = le32_to_cpu(ip->virtualUnits);
 192                         ip->firstUnit = le32_to_cpu(ip->firstUnit);
 193                         ip->lastUnit = le32_to_cpu(ip->lastUnit);
 194                         ip->flags = le32_to_cpu(ip->flags);
 195                         ip->spareUnits = le32_to_cpu(ip->spareUnits);
 196                         ip->Reserved0 = le32_to_cpu(ip->Reserved0);
 197
 198                         pr_debug("    PARTITION[%d] ->\n"
 199                                  "        virtualUnits    = %d\n"
 200                                  "        firstUnit       = %d\n"
 201                                  "        lastUnit        = %d\n"
 202                                  "        flags           = 0x%x\n"
 203                                  "        spareUnits      = %d\n",
 204                                  i, ip->virtualUnits, ip->firstUnit,
 205                                  ip->lastUnit, ip->flags,
 206                                  ip->spareUnits);
 207
 208                         if (ip->Reserved0 != ip->firstUnit) {
 209                                 struct erase_info *instr = &inftl->instr;
 210
 211                                 /*
 212                                  *      Most likely this is using the
 213                                  *      undocumented qiuck mount feature.
 214                                  *      We don't support that, we will need
 215                                  *      to erase the hidden block for full
 216                                  *      compatibility.
 217                                  */
 218                                 instr->addr = ip->Reserved0 * inftl->EraseSize;
 219                                 instr->len = inftl->EraseSize;
 220                                 mtd_erase(mtd, instr);
 221                         }
 222                         if ((ip->lastUnit - ip->firstUnit + 1) < ip->virtualUnits) {
 223                                 printk(KERN_WARNING "INFTL: Media Header "
 224                                         "Partition %d sanity check failed\n"
 225                                         "    firstUnit %d : lastUnit %d  >  "
 226                                         "virtualUnits %d\n", i, ip->lastUnit,
 227                                         ip->firstUnit, ip->Reserved0);
 228                                 return -1;
 229                         }
 230                         if (ip->Reserved1 != 0) {
 231                                 printk(KERN_WARNING "INFTL: Media Header "
 232                                         "Partition %d sanity check failed: "
 233                                         "Reserved1 %d != 0\n",
 234                                         i, ip->Reserved1);
 235                                 return -1;
 236                         }
 237
 238                         if (ip->flags & INFTL_BDTL)
 239                                 break;
 240                 }
 241
 242                 if (i >= 4) {
 243                         printk(KERN_WARNING "INFTL: Media Header Partition "
 244                                 "sanity check failed:\n       No partition "
 245                                 "marked as Disk Partition\n");
 246                         return -1;
 247                 }
 248
 249                 inftl->nb_boot_blocks = ip->firstUnit;
 250                 inftl->numvunits = ip->virtualUnits;
 251                 if (inftl->numvunits > (inftl->nb_blocks -
 252                     inftl->nb_boot_blocks - 2)) {
 253                         printk(KERN_WARNING "INFTL: Media Header sanity check "
 254                                 "failed:\n        numvunits (%d) > nb_blocks "
 255                                 "(%d) - nb_boot_blocks(%d) - 2\n",
 256                                 inftl->numvunits, inftl->nb_blocks,
 257                                 inftl->nb_boot_blocks);
 258                         return -1;
 259                 }
 260
 261                 inftl->mbd.size  = inftl->numvunits *
 262                         (inftl->EraseSize / SECTORSIZE);
 263
 264                 /*
 265                  * Block count is set to last used EUN (we won't need to keep
 266                  * any meta-data past that point).
 267                  */
 268                 inftl->firstEUN = ip->firstUnit;
 269                 inftl->lastEUN = ip->lastUnit;
 270                 inftl->nb_blocks = ip->lastUnit + 1;
 271
 272                 /* Memory alloc */
 273                 inftl->PUtable = kmalloc_array(inftl->nb_blocks, sizeof(u16),
 274                                                GFP_KERNEL);
 275                 if (!inftl->PUtable) {
 276                         printk(KERN_WARNING "INFTL: allocation of PUtable "
 277                                 "failed (%zd bytes)\n",
 278                                 inftl->nb_blocks * sizeof(u16));
 279                         return -ENOMEM;
 280                 }
 281
 282                 inftl->VUtable = kmalloc_array(inftl->nb_blocks, sizeof(u16),
 283                                                GFP_KERNEL);
 284                 if (!inftl->VUtable) {
 285                         kfree(inftl->PUtable);
 286                         printk(KERN_WARNING "INFTL: allocation of VUtable "
 287                                 "failed (%zd bytes)\n",
 288                                 inftl->nb_blocks * sizeof(u16));
 289                         return -ENOMEM;
 290                 }
 291
 292                 /* Mark the blocks before INFTL MediaHeader as reserved */
 293                 for (i = 0; i < inftl->nb_boot_blocks; i++)
 294                         inftl->PUtable[i] = BLOCK_RESERVED;
 295                 /* Mark all remaining blocks as potentially containing data */
 296                 for (; i < inftl->nb_blocks; i++)
 297                         inftl->PUtable[i] = BLOCK_NOTEXPLORED;
 298
 299                 /* Mark this boot record (NFTL MediaHeader) block as reserved */
 300                 inftl->PUtable[block] = BLOCK_RESERVED;
 301
 302                 /* Read Bad Erase Unit Table and modify PUtable[] accordingly */
 303                 for (i = 0; i < inftl->nb_blocks; i++) {
 304                         int physblock;
 305                         /* If any of the physical eraseblocks are bad, don't
 306                            use the unit. */
 307                         for (physblock = 0; physblock < inftl->EraseSize; physblock += inftl->mbd.mtd->erasesize) {
 308                                 if (mtd_block_isbad(inftl->mbd.mtd,
 309                                                     i * inftl->EraseSize + physblock))
 310                                         inftl->PUtable[i] = BLOCK_RESERVED;
 311                         }
 312                 }
 313
 314                 inftl->MediaUnit = block;
 315                 return 0;
 316         }
 317
 318         /* Not found. */
 319         return -1;
 320 }
 321
 322 static int memcmpb(void *a, int c, int n)
 323 {
 324         int i;
 325         for (i = 0; i < n; i++) {
 326                 if (c != ((unsigned char *)a)[i])
 327                         return 1;
 328         }
 329         return 0;
 330 }
 331
 332 /*
 333  * check_free_sector: check if a free sector is actually FREE,
 334  *      i.e. All 0xff in data and oob area.
 335  */
 336 static int check_free_sectors(struct INFTLrecord *inftl, unsigned int address,
 337         int len, int check_oob)
 338 {
 339         struct mtd_info *mtd = inftl->mbd.mtd;
 340         size_t retlen;
 341         int i, ret;
 342         u8 *buf;
 343
 344         buf = kmalloc(SECTORSIZE + mtd->oobsize, GFP_KERNEL);
 345         if (!buf)
 346                 return -1;
 347
 348         ret = -1;
 349         for (i = 0; i < len; i += SECTORSIZE) {
 350                 if (mtd_read(mtd, address, SECTORSIZE, &retlen, buf))
 351                         goto out;
 352                 if (memcmpb(buf, 0xff, SECTORSIZE) != 0)
 353                         goto out;
 354
 355                 if (check_oob) {
 356                         if(inftl_read_oob(mtd, address, mtd->oobsize,
 357                                           &retlen, &buf[SECTORSIZE]) < 0)
 358                                 goto out;
 359                         if (memcmpb(buf + SECTORSIZE, 0xff, mtd->oobsize) != 0)
 360                                 goto out;
 361                 }
 362                 address += SECTORSIZE;
 363         }
 364
 365         ret = 0;
 366
 367 out:
 368         kfree(buf);
 369         return ret;
 370 }
 371
 372 /*
 373  * INFTL_format: format a Erase Unit by erasing ALL Erase Zones in the Erase
 374  *               Unit and Update INFTL metadata. Each erase operation is
 375  *               checked with check_free_sectors.
 376  *
 377  * Return: 0 when succeed, -1 on error.
 378  *
 379  * ToDo: 1. Is it necessary to check_free_sector after erasing ??
 380  */
 381 int INFTL_formatblock(struct INFTLrecord *inftl, int block)
 382 {
 383         size_t retlen;
 384         struct inftl_unittail uci;
 385         struct erase_info *instr = &inftl->instr;
 386         struct mtd_info *mtd = inftl->mbd.mtd;
 387         int physblock;
 388
 389         pr_debug("INFTL: INFTL_formatblock(inftl=%p,block=%d)\n", inftl, block);
 390
 391         memset(instr, 0, sizeof(struct erase_info));
 392
 393         /* FIXME: Shouldn't we be setting the 'discarded' flag to zero
 394            _first_? */
 395
 396         /* Use async erase interface, test return code */
 397         instr->addr = block * inftl->EraseSize;
 398         instr->len = inftl->mbd.mtd->erasesize;
 399         /* Erase one physical eraseblock at a time, even though the NAND api
 400            allows us to group them.  This way we if we have a failure, we can
 401            mark only the failed block in the bbt. */
 402         for (physblock = 0; physblock < inftl->EraseSize;
 403              physblock += instr->len, instr->addr += instr->len) {
 404                 int ret;
 405
 406                 ret = mtd_erase(inftl->mbd.mtd, instr);
 407                 if (ret) {
 408                         printk(KERN_WARNING "INFTL: error while formatting block %d\n",
 409                                 block);
 410                         goto fail;
 411                 }
 412
 413                 /*
 414                  * Check the "freeness" of Erase Unit before updating metadata.
 415                  * FixMe: is this check really necessary? Since we have check
 416                  * the return code after the erase operation.
 417                  */
 418                 if (check_free_sectors(inftl, instr->addr, instr->len, 1) != 0)
 419                         goto fail;
 420         }
 421
 422         uci.EraseMark = cpu_to_le16(ERASE_MARK);
 423         uci.EraseMark1 = cpu_to_le16(ERASE_MARK);
 424         uci.Reserved[0] = 0;
 425         uci.Reserved[1] = 0;
 426         uci.Reserved[2] = 0;
 427         uci.Reserved[3] = 0;
 428         instr->addr = block * inftl->EraseSize + SECTORSIZE * 2;
 429         if (inftl_write_oob(mtd, instr->addr + 8, 8, &retlen, (char *)&uci) < 0)
 430                 goto fail;
 431         return 0;
 432 fail:
 433         /* could not format, update the bad block table (caller is responsible
 434            for setting the PUtable to BLOCK_RESERVED on failure) */
 435         mtd_block_markbad(inftl->mbd.mtd, instr->addr);
 436         return -1;
 437 }
 438
 439 /*
 440  * format_chain: Format an invalid Virtual Unit chain. It frees all the Erase
 441  *      Units in a Virtual Unit Chain, i.e. all the units are disconnected.
 442  *
 443  *      Since the chain is invalid then we will have to erase it from its
 444  *      head (normally for INFTL we go from the oldest). But if it has a
 445  *      loop then there is no oldest...
 446  */
 447 static void format_chain(struct INFTLrecord *inftl, unsigned int first_block)
 448 {
 449         unsigned int block = first_block, block1;
 450
 451         printk(KERN_WARNING "INFTL: formatting chain at block %d\n",
 452                 first_block);
 453
 454         for (;;) {
 455                 block1 = inftl->PUtable[block];
 456
 457                 printk(KERN_WARNING "INFTL: formatting block %d\n", block);
 458                 if (INFTL_formatblock(inftl, block) < 0) {
 459                         /*
 460                          * Cannot format !!!! Mark it as Bad Unit,
 461                          */
 462                         inftl->PUtable[block] = BLOCK_RESERVED;
 463                 } else {
 464                         inftl->PUtable[block] = BLOCK_FREE;
 465                 }
 466
 467                 /* Goto next block on the chain */
 468                 block = block1;
 469
 470                 if (block == BLOCK_NIL || block >= inftl->lastEUN)
 471                         break;
 472         }
 473 }
 474
 475 void INFTL_dumptables(struct INFTLrecord *s)
 476 {
 477         int i;
 478
 479         pr_debug("-------------------------------------------"
 480                 "----------------------------------\n");
 481
 482         pr_debug("VUtable[%d] ->", s->nb_blocks);
 483         for (i = 0; i < s->nb_blocks; i++) {
 484                 if ((i % 8) == 0)
 485                         pr_debug("\n%04x: ", i);
 486                 pr_debug("%04x ", s->VUtable[i]);
 487         }
 488
 489         pr_debug("\n-------------------------------------------"
 490                 "----------------------------------\n");
 491
 492         pr_debug("PUtable[%d-%d=%d] ->", s->firstEUN, s->lastEUN, s->nb_blocks);
 493         for (i = 0; i <= s->lastEUN; i++) {
 494                 if ((i % 8) == 0)
 495                         pr_debug("\n%04x: ", i);
 496                 pr_debug("%04x ", s->PUtable[i]);
 497         }
 498
 499         pr_debug("\n-------------------------------------------"
 500                 "----------------------------------\n");
 501
 502         pr_debug("INFTL ->\n"
 503                 "  EraseSize       = %d\n"
 504                 "  h/s/c           = %d/%d/%d\n"
 505                 "  numvunits       = %d\n"
 506                 "  firstEUN        = %d\n"
 507                 "  lastEUN         = %d\n"
 508                 "  numfreeEUNs     = %d\n"
 509                 "  LastFreeEUN     = %d\n"
 510                 "  nb_blocks       = %d\n"
 511                 "  nb_boot_blocks  = %d",
 512                 s->EraseSize, s->heads, s->sectors, s->cylinders,
 513                 s->numvunits, s->firstEUN, s->lastEUN, s->numfreeEUNs,
 514                 s->LastFreeEUN, s->nb_blocks, s->nb_boot_blocks);
 515
 516         pr_debug("\n-------------------------------------------"
 517                 "----------------------------------\n");
 518 }
 519
 520 void INFTL_dumpVUchains(struct INFTLrecord *s)
 521 {
 522         int logical, block, i;
 523
 524         pr_debug("-------------------------------------------"
 525                 "----------------------------------\n");
 526
 527         pr_debug("INFTL Virtual Unit Chains:\n");
 528         for (logical = 0; logical < s->nb_blocks; logical++) {
 529                 block = s->VUtable[logical];
 530                 if (block >= s->nb_blocks)
 531                         continue;
 532                 pr_debug("  LOGICAL %d --> %d ", logical, block);
 533                 for (i = 0; i < s->nb_blocks; i++) {
 534                         if (s->PUtable[block] == BLOCK_NIL)
 535                                 break;
 536                         block = s->PUtable[block];
 537                         pr_debug("%d ", block);
 538                 }
 539                 pr_debug("\n");
 540         }
 541
 542         pr_debug("-------------------------------------------"
 543                 "----------------------------------\n");
 544 }
 545
 546 int INFTL_mount(struct INFTLrecord *s)
 547 {
 548         struct mtd_info *mtd = s->mbd.mtd;
 549         unsigned int block, first_block, prev_block, last_block;
 550         unsigned int first_logical_block, logical_block, erase_mark;
 551         int chain_length, do_format_chain;
 552         struct inftl_unithead1 h0;
 553         struct inftl_unittail h1;
 554         size_t retlen;
 555         int i;
 556         u8 *ANACtable, ANAC;
 557
 558         pr_debug("INFTL: INFTL_mount(inftl=%p)\n", s);
 559
 560         /* Search for INFTL MediaHeader and Spare INFTL Media Header */
 561         if (find_boot_record(s) < 0) {
 562                 printk(KERN_WARNING "INFTL: could not find valid boot record?\n");
 563                 return -ENXIO;
 564         }
 565
 566         /* Init the logical to physical table */
 567         for (i = 0; i < s->nb_blocks; i++)
 568                 s->VUtable[i] = BLOCK_NIL;
 569
 570         logical_block = block = BLOCK_NIL;
 571
 572         /* Temporary buffer to store ANAC numbers. */
 573         ANACtable = kcalloc(s->nb_blocks, sizeof(u8), GFP_KERNEL);
 574         if (!ANACtable) {
 575                 printk(KERN_WARNING "INFTL: allocation of ANACtable "
 576                                 "failed (%zd bytes)\n",
 577                                 s->nb_blocks * sizeof(u8));
 578                 return -ENOMEM;
 579         }
 580
 581         /*
 582          * First pass is to explore each physical unit, and construct the
 583          * virtual chains that exist (newest physical unit goes into VUtable).
 584          * Any block that is in any way invalid will be left in the
 585          * NOTEXPLORED state. Then at the end we will try to format it and
 586          * mark it as free.
 587          */
 588         pr_debug("INFTL: pass 1, explore each unit\n");
 589         for (first_block = s->firstEUN; first_block <= s->lastEUN; first_block++) {
 590                 if (s->PUtable[first_block] != BLOCK_NOTEXPLORED)
 591                         continue;
 592
 593                 do_format_chain = 0;
 594                 first_logical_block = BLOCK_NIL;
 595                 last_block = BLOCK_NIL;
 596                 block = first_block;
 597
 598                 for (chain_length = 0; ; chain_length++) {
 599
 600                         if ((chain_length == 0) &&
 601                             (s->PUtable[block] != BLOCK_NOTEXPLORED)) {
 602                                 /* Nothing to do here, onto next block */
 603                                 break;
 604                         }
 605
 606                         if (inftl_read_oob(mtd, block * s->EraseSize + 8,
 607                                            8, &retlen, (char *)&h0) < 0 ||
 608                             inftl_read_oob(mtd, block * s->EraseSize +
 609                                            2 * SECTORSIZE + 8, 8, &retlen,
 610                                            (char *)&h1) < 0) {
 611                                 /* Should never happen? */
 612                                 do_format_chain++;
 613                                 break;
 614                         }
 615
 616                         logical_block = le16_to_cpu(h0.virtualUnitNo);
 617                         prev_block = le16_to_cpu(h0.prevUnitNo);
 618                         erase_mark = le16_to_cpu((h1.EraseMark | h1.EraseMark1));
 619                         ANACtable[block] = h0.ANAC;
 620
 621                         /* Previous block is relative to start of Partition */
 622                         if (prev_block < s->nb_blocks)
 623                                 prev_block += s->firstEUN;
 624
 625                         /* Already explored partial chain? */
 626                         if (s->PUtable[block] != BLOCK_NOTEXPLORED) {
 627                                 /* Check if chain for this logical */
 628                                 if (logical_block == first_logical_block) {
 629                                         if (last_block != BLOCK_NIL)
 630                                                 s->PUtable[last_block] = block;
 631                                 }
 632                                 break;
 633                         }
 634
 635                         /* Check for invalid block */
 636                         if (erase_mark != ERASE_MARK) {
 637                                 printk(KERN_WARNING "INFTL: corrupt block %d "
 638                                         "in chain %d, chain length %d, erase "
 639                                         "mark 0x%x?\n", block, first_block,
 640                                         chain_length, erase_mark);
 641                                 /*
 642                                  * Assume end of chain, probably incomplete
 643                                  * fold/erase...
 644                                  */
 645                                 if (chain_length == 0)
 646                                         do_format_chain++;
 647                                 break;
 648                         }
 649
 650                         /* Check for it being free already then... */
 651                         if ((logical_block == BLOCK_FREE) ||
 652                             (logical_block == BLOCK_NIL)) {
 653                                 s->PUtable[block] = BLOCK_FREE;
 654                                 break;
 655                         }
 656
 657                         /* Sanity checks on block numbers */
 658                         if ((logical_block >= s->nb_blocks) ||
 659                             ((prev_block >= s->nb_blocks) &&
 660                              (prev_block != BLOCK_NIL))) {
 661                                 if (chain_length > 0) {
 662                                         printk(KERN_WARNING "INFTL: corrupt "
 663                                                 "block %d in chain %d?\n",
 664                                                 block, first_block);
 665                                         do_format_chain++;
 666                                 }
 667                                 break;
 668                         }
 669
 670                         if (first_logical_block == BLOCK_NIL) {
 671                                 first_logical_block = logical_block;
 672                         } else {
 673                                 if (first_logical_block != logical_block) {
 674                                         /* Normal for folded chain... */
 675                                         break;
 676                                 }
 677                         }
 678
 679                         /*
 680                          * Current block is valid, so if we followed a virtual
 681                          * chain to get here then we can set the previous
 682                          * block pointer in our PUtable now. Then move onto
 683                          * the previous block in the chain.
 684                          */
 685                         s->PUtable[block] = BLOCK_NIL;
 686                         if (last_block != BLOCK_NIL)
 687                                 s->PUtable[last_block] = block;
 688                         last_block = block;
 689                         block = prev_block;
 690
 691                         /* Check for end of chain */
 692                         if (block == BLOCK_NIL)
 693                                 break;
 694
 695                         /* Validate next block before following it... */
 696                         if (block > s->lastEUN) {
 697                                 printk(KERN_WARNING "INFTL: invalid previous "
 698                                         "block %d in chain %d?\n", block,
 699                                         first_block);
 700                                 do_format_chain++;
 701                                 break;
 702                         }
 703                 }
 704
 705                 if (do_format_chain) {
 706                         format_chain(s, first_block);
 707                         continue;
 708                 }
 709
 710                 /*
 711                  * Looks like a valid chain then. It may not really be the
 712                  * newest block in the chain, but it is the newest we have
 713                  * found so far. We might update it in later iterations of
 714                  * this loop if we find something newer.
 715                  */
 716                 s->VUtable[first_logical_block] = first_block;
 717                 logical_block = BLOCK_NIL;
 718         }
 719
 720         INFTL_dumptables(s);
 721
 722         /*
 723          * Second pass, check for infinite loops in chains. These are
 724          * possible because we don't update the previous pointers when
 725          * we fold chains. No big deal, just fix them up in PUtable.
 726          */
 727         pr_debug("INFTL: pass 2, validate virtual chains\n");
 728         for (logical_block = 0; logical_block < s->numvunits; logical_block++) {
 729                 block = s->VUtable[logical_block];
 730                 last_block = BLOCK_NIL;
 731
 732                 /* Check for free/reserved/nil */
 733                 if (block >= BLOCK_RESERVED)
 734                         continue;
 735
 736                 ANAC = ANACtable[block];
 737                 for (i = 0; i < s->numvunits; i++) {
 738                         if (s->PUtable[block] == BLOCK_NIL)
 739                                 break;
 740                         if (s->PUtable[block] > s->lastEUN) {
 741                                 printk(KERN_WARNING "INFTL: invalid prev %d, "
 742                                         "in virtual chain %d\n",
 743                                         s->PUtable[block], logical_block);
 744                                 s->PUtable[block] = BLOCK_NIL;
 745
 746                         }
 747                         if (ANACtable[block] != ANAC) {
 748                                 /*
 749                                  * Chain must point back to itself. This is ok,
 750                                  * but we will need adjust the tables with this
 751                                  * newest block and oldest block.
 752                                  */
 753                                 s->VUtable[logical_block] = block;
 754                                 s->PUtable[last_block] = BLOCK_NIL;
 755                                 break;
 756                         }
 757
 758                         ANAC--;
 759                         last_block = block;
 760                         block = s->PUtable[block];
 761                 }
 762
 763                 if (i >= s->nb_blocks) {
 764                         /*
 765                          * Uhoo, infinite chain with valid ANACS!
 766                          * Format whole chain...
 767                          */
 768                         format_chain(s, first_block);
 769                 }
 770         }
 771
 772         INFTL_dumptables(s);
 773         INFTL_dumpVUchains(s);
 774
 775         /*
 776          * Third pass, format unreferenced blocks and init free block count.
 777          */
 778         s->numfreeEUNs = 0;
 779         s->LastFreeEUN = BLOCK_NIL;
 780
 781         pr_debug("INFTL: pass 3, format unused blocks\n");
 782         for (block = s->firstEUN; block <= s->lastEUN; block++) {
 783                 if (s->PUtable[block] == BLOCK_NOTEXPLORED) {
 784                         printk("INFTL: unreferenced block %d, formatting it\n",
 785                                 block);
 786                         if (INFTL_formatblock(s, block) < 0)
 787                                 s->PUtable[block] = BLOCK_RESERVED;
 788                         else
 789                                 s->PUtable[block] = BLOCK_FREE;
 790                 }
 791                 if (s->PUtable[block] == BLOCK_FREE) {
 792                         s->numfreeEUNs++;
 793                         if (s->LastFreeEUN == BLOCK_NIL)
 794                                 s->LastFreeEUN = block;
 795                 }
 796         }
 797
 798         kfree(ANACtable);
 799         return 0;
 800 }