drivers/mtd/inftlmount.c

   1 /*
   2  * inftlmount.c -- INFTL mount code with extensive checks.
   3  *
   4  * Author: Greg Ungerer (gerg@snapgear.com)
   5  * (C) 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 (C) 2000 Netgem S.A.
  10  *
  11  * $Id: inftlmount.c,v 1.18 2005/11/07 11:14:20 gleixner Exp $
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  26  */
  27
  28 #include <linux/kernel.h>
  29 #include <linux/module.h>
  30 #include <asm/errno.h>
  31 #include <asm/io.h>
  32 #include <asm/uaccess.h>
  33 #include <linux/miscdevice.h>
  34 #include <linux/delay.h>
  35 #include <linux/slab.h>
  36 #include <linux/init.h>
  37 #include <linux/mtd/mtd.h>
  38 #include <linux/mtd/nftl.h>
  39 #include <linux/mtd/inftl.h>
  40 #include <linux/mtd/compatmac.h>
  41
  42 char inftlmountrev[]="$Revision: 1.18 $";
  43
  44 extern int inftl_read_oob(struct mtd_info *mtd, loff_t offs, size_t len,
  45                           size_t *retlen, uint8_t *buf);
  46 extern int inftl_write_oob(struct mtd_info *mtd, loff_t offs, size_t len,
  47                            size_t *retlen, uint8_t *buf);
  48
  49 /*
  50  * find_boot_record: Find the INFTL Media Header and its Spare copy which
  51  *      contains the various device information of the INFTL partition and
  52  *      Bad Unit Table. Update the PUtable[] table according to the Bad
  53  *      Unit Table. PUtable[] is used for management of Erase Unit in
  54  *      other routines in inftlcore.c and inftlmount.c.
  55  */
  56 static int find_boot_record(struct INFTLrecord *inftl)
  57 {
  58         struct inftl_unittail h1;
  59         //struct inftl_oob oob;
  60         unsigned int i, block;
  61         u8 buf[SECTORSIZE];
  62         struct INFTLMediaHeader *mh = &inftl->MediaHdr;
  63         struct mtd_info *mtd = inftl->mbd.mtd;
  64         struct INFTLPartition *ip;
  65         size_t retlen;
  66
  67         DEBUG(MTD_DEBUG_LEVEL3, "INFTL: find_boot_record(inftl=%p)\n", inftl);
  68
  69         /*
  70          * Assume logical EraseSize == physical erasesize for starting the
  71          * scan. We'll sort it out later if we find a MediaHeader which says
  72          * otherwise.
  73          */
  74         inftl->EraseSize = inftl->mbd.mtd->erasesize;
  75         inftl->nb_blocks = inftl->mbd.mtd->size / inftl->EraseSize;
  76
  77         inftl->MediaUnit = BLOCK_NIL;
  78
  79         /* Search for a valid boot record */
  80         for (block = 0; block < inftl->nb_blocks; block++) {
  81                 int ret;
  82
  83                 /*
  84                  * Check for BNAND header first. Then whinge if it's found
  85                  * but later checks fail.
  86                  */
  87                 ret = mtd->read(mtd, block * inftl->EraseSize,
  88                                 SECTORSIZE, &retlen, buf);
  89                 /* We ignore ret in case the ECC of the MediaHeader is invalid
  90                    (which is apparently acceptable) */
  91                 if (retlen != SECTORSIZE) {
  92                         static int warncount = 5;
  93
  94                         if (warncount) {
  95                                 printk(KERN_WARNING "INFTL: block read at 0x%x "
  96                                         "of mtd%d failed: %d\n",
  97                                         block * inftl->EraseSize,
  98                                         inftl->mbd.mtd->index, ret);
  99                                 if (!--warncount)
 100                                         printk(KERN_WARNING "INFTL: further "
 101                                                 "failures for this block will "
 102                                                 "not be printed\n");
 103                         }
 104                         continue;
 105                 }
 106
 107                 if (retlen < 6 || memcmp(buf, "BNAND", 6)) {
 108                         /* BNAND\0 not found. Continue */
 109                         continue;
 110                 }
 111
 112                 /* To be safer with BIOS, also use erase mark as discriminant */
 113                 if ((ret = inftl_read_oob(mtd, block * inftl->EraseSize +
 114                                           SECTORSIZE + 8, 8, &retlen,
 115                                           (char *)&h1) < 0)) {
 116                         printk(KERN_WARNING "INFTL: ANAND header found at "
 117                                 "0x%x in mtd%d, but OOB data read failed "
 118                                 "(err %d)\n", block * inftl->EraseSize,
 119                                 inftl->mbd.mtd->index, ret);
 120                         continue;
 121                 }
 122
 123
 124                 /*
 125                  * This is the first we've seen.
 126                  * Copy the media header structure into place.
 127                  */
 128                 memcpy(mh, buf, sizeof(struct INFTLMediaHeader));
 129
 130                 /* Read the spare media header at offset 4096 */
 131                 mtd->read(mtd, block * inftl->EraseSize + 4096,
 132                           SECTORSIZE, &retlen, buf);
 133                 if (retlen != SECTORSIZE) {
 134                         printk(KERN_WARNING "INFTL: Unable to read spare "
 135                                "Media Header\n");
 136                         return -1;
 137                 }
 138                 /* Check if this one is the same as the first one we found. */
 139                 if (memcmp(mh, buf, sizeof(struct INFTLMediaHeader))) {
 140                         printk(KERN_WARNING "INFTL: Primary and spare Media "
 141                                "Headers disagree.\n");
 142                         return -1;
 143                 }
 144
 145                 mh->NoOfBootImageBlocks = le32_to_cpu(mh->NoOfBootImageBlocks);
 146                 mh->NoOfBinaryPartitions = le32_to_cpu(mh->NoOfBinaryPartitions);
 147                 mh->NoOfBDTLPartitions = le32_to_cpu(mh->NoOfBDTLPartitions);
 148                 mh->BlockMultiplierBits = le32_to_cpu(mh->BlockMultiplierBits);
 149                 mh->FormatFlags = le32_to_cpu(mh->FormatFlags);
 150                 mh->PercentUsed = le32_to_cpu(mh->PercentUsed);
 151
 152 #ifdef CONFIG_MTD_DEBUG_VERBOSE
 153                 if (CONFIG_MTD_DEBUG_VERBOSE >= 2) {
 154                         printk("INFTL: Media Header ->\n"
 155                                 "    bootRecordID          = %s\n"
 156                                 "    NoOfBootImageBlocks   = %d\n"
 157                                 "    NoOfBinaryPartitions  = %d\n"
 158                                 "    NoOfBDTLPartitions    = %d\n"
 159                                 "    BlockMultiplerBits    = %d\n"
 160                                 "    FormatFlgs            = %d\n"
 161                                 "    OsakVersion           = 0x%x\n"
 162                                 "    PercentUsed           = %d\n",
 163                                 mh->bootRecordID, mh->NoOfBootImageBlocks,
 164                                 mh->NoOfBinaryPartitions,
 165                                 mh->NoOfBDTLPartitions,
 166                                 mh->BlockMultiplierBits, mh->FormatFlags,
 167                                 mh->OsakVersion, mh->PercentUsed);
 168                 }
 169 #endif
 170
 171                 if (mh->NoOfBDTLPartitions == 0) {
 172                         printk(KERN_WARNING "INFTL: Media Header sanity check "
 173                                 "failed: NoOfBDTLPartitions (%d) == 0, "
 174                                 "must be at least 1\n", mh->NoOfBDTLPartitions);
 175                         return -1;
 176                 }
 177
 178                 if ((mh->NoOfBDTLPartitions + mh->NoOfBinaryPartitions) > 4) {
 179                         printk(KERN_WARNING "INFTL: Media Header sanity check "
 180                                 "failed: Total Partitions (%d) > 4, "
 181                                 "BDTL=%d Binary=%d\n", mh->NoOfBDTLPartitions +
 182                                 mh->NoOfBinaryPartitions,
 183                                 mh->NoOfBDTLPartitions,
 184                                 mh->NoOfBinaryPartitions);
 185                         return -1;
 186                 }
 187
 188                 if (mh->BlockMultiplierBits > 1) {
 189                         printk(KERN_WARNING "INFTL: sorry, we don't support "
 190                                 "UnitSizeFactor 0x%02x\n",
 191                                 mh->BlockMultiplierBits);
 192                         return -1;
 193                 } else if (mh->BlockMultiplierBits == 1) {
 194                         printk(KERN_WARNING "INFTL: support for INFTL with "
 195                                 "UnitSizeFactor 0x%02x is experimental\n",
 196                                 mh->BlockMultiplierBits);
 197                         inftl->EraseSize = inftl->mbd.mtd->erasesize <<
 198                                 mh->BlockMultiplierBits;
 199                         inftl->nb_blocks = inftl->mbd.mtd->size / inftl->EraseSize;
 200                         block >>= mh->BlockMultiplierBits;
 201                 }
 202
 203                 /* Scan the partitions */
 204                 for (i = 0; (i < 4); i++) {
 205                         ip = &mh->Partitions[i];
 206                         ip->virtualUnits = le32_to_cpu(ip->virtualUnits);
 207                         ip->firstUnit = le32_to_cpu(ip->firstUnit);
 208                         ip->lastUnit = le32_to_cpu(ip->lastUnit);
 209                         ip->flags = le32_to_cpu(ip->flags);
 210                         ip->spareUnits = le32_to_cpu(ip->spareUnits);
 211                         ip->Reserved0 = le32_to_cpu(ip->Reserved0);
 212
 213 #ifdef CONFIG_MTD_DEBUG_VERBOSE
 214                         if (CONFIG_MTD_DEBUG_VERBOSE >= 2) {
 215                                 printk("    PARTITION[%d] ->\n"
 216                                         "        virtualUnits    = %d\n"
 217                                         "        firstUnit       = %d\n"
 218                                         "        lastUnit        = %d\n"
 219                                         "        flags           = 0x%x\n"
 220                                         "        spareUnits      = %d\n",
 221                                         i, ip->virtualUnits, ip->firstUnit,
 222                                         ip->lastUnit, ip->flags,
 223                                         ip->spareUnits);
 224                         }
 225 #endif
 226
 227                         if (ip->Reserved0 != ip->firstUnit) {
 228                                 struct erase_info *instr = &inftl->instr;
 229
 230                                 instr->mtd = inftl->mbd.mtd;
 231
 232                                 /*
 233                                  *      Most likely this is using the
 234                                  *      undocumented qiuck mount feature.
 235                                  *      We don't support that, we will need
 236                                  *      to erase the hidden block for full
 237                                  *      compatibility.
 238                                  */
 239                                 instr->addr = ip->Reserved0 * inftl->EraseSize;
 240                                 instr->len = inftl->EraseSize;
 241                                 mtd->erase(mtd, instr);
 242                         }
 243                         if ((ip->lastUnit - ip->firstUnit + 1) < ip->virtualUnits) {
 244                                 printk(KERN_WARNING "INFTL: Media Header "
 245                                         "Partition %d sanity check failed\n"
 246                                         "    firstUnit %d : lastUnit %d  >  "
 247                                         "virtualUnits %d\n", i, ip->lastUnit,
 248                                         ip->firstUnit, ip->Reserved0);
 249                                 return -1;
 250                         }
 251                         if (ip->Reserved1 != 0) {
 252                                 printk(KERN_WARNING "INFTL: Media Header "
 253                                         "Partition %d sanity check failed: "
 254                                         "Reserved1 %d != 0\n",
 255                                         i, ip->Reserved1);
 256                                 return -1;
 257                         }
 258
 259                         if (ip->flags & INFTL_BDTL)
 260                                 break;
 261                 }
 262
 263                 if (i >= 4) {
 264                         printk(KERN_WARNING "INFTL: Media Header Partition "
 265                                 "sanity check failed:\n       No partition "
 266                                 "marked as Disk Partition\n");
 267                         return -1;
 268                 }
 269
 270                 inftl->nb_boot_blocks = ip->firstUnit;
 271                 inftl->numvunits = ip->virtualUnits;
 272                 if (inftl->numvunits > (inftl->nb_blocks -
 273                     inftl->nb_boot_blocks - 2)) {
 274                         printk(KERN_WARNING "INFTL: Media Header sanity check "
 275                                 "failed:\n        numvunits (%d) > nb_blocks "
 276                                 "(%d) - nb_boot_blocks(%d) - 2\n",
 277                                 inftl->numvunits, inftl->nb_blocks,
 278                                 inftl->nb_boot_blocks);
 279                         return -1;
 280                 }
 281
 282                 inftl->mbd.size  = inftl->numvunits *
 283                         (inftl->EraseSize / SECTORSIZE);
 284
 285                 /*
 286                  * Block count is set to last used EUN (we won't need to keep
 287                  * any meta-data past that point).
 288                  */
 289                 inftl->firstEUN = ip->firstUnit;
 290                 inftl->lastEUN = ip->lastUnit;
 291                 inftl->nb_blocks = ip->lastUnit + 1;
 292
 293                 /* Memory alloc */
 294                 inftl->PUtable = kmalloc(inftl->nb_blocks * sizeof(u16), GFP_KERNEL);
 295                 if (!inftl->PUtable) {
 296                         printk(KERN_WARNING "INFTL: allocation of PUtable "
 297                                 "failed (%zd bytes)\n",
 298                                 inftl->nb_blocks * sizeof(u16));
 299                         return -ENOMEM;
 300                 }
 301
 302                 inftl->VUtable = kmalloc(inftl->nb_blocks * sizeof(u16), GFP_KERNEL);
 303                 if (!inftl->VUtable) {
 304                         kfree(inftl->PUtable);
 305                         printk(KERN_WARNING "INFTL: allocation of VUtable "
 306                                 "failed (%zd bytes)\n",
 307                                 inftl->nb_blocks * sizeof(u16));
 308                         return -ENOMEM;
 309                 }
 310
 311                 /* Mark the blocks before INFTL MediaHeader as reserved */
 312                 for (i = 0; i < inftl->nb_boot_blocks; i++)
 313                         inftl->PUtable[i] = BLOCK_RESERVED;
 314                 /* Mark all remaining blocks as potentially containing data */
 315                 for (; i < inftl->nb_blocks; i++)
 316                         inftl->PUtable[i] = BLOCK_NOTEXPLORED;
 317
 318                 /* Mark this boot record (NFTL MediaHeader) block as reserved */
 319                 inftl->PUtable[block] = BLOCK_RESERVED;
 320
 321                 /* Read Bad Erase Unit Table and modify PUtable[] accordingly */
 322                 for (i = 0; i < inftl->nb_blocks; i++) {
 323                         int physblock;
 324                         /* If any of the physical eraseblocks are bad, don't
 325                            use the unit. */
 326                         for (physblock = 0; physblock < inftl->EraseSize; physblock += inftl->mbd.mtd->erasesize) {
 327                                 if (inftl->mbd.mtd->block_isbad(inftl->mbd.mtd, i * inftl->EraseSize + physblock))
 328                                         inftl->PUtable[i] = BLOCK_RESERVED;
 329                         }
 330                 }
 331
 332                 inftl->MediaUnit = block;
 333                 return 0;
 334         }
 335
 336         /* Not found. */
 337         return -1;
 338 }
 339
 340 static int memcmpb(void *a, int c, int n)
 341 {
 342         int i;
 343         for (i = 0; i < n; i++) {
 344                 if (c != ((unsigned char *)a)[i])
 345                         return 1;
 346         }
 347         return 0;
 348 }
 349
 350 /*
 351  * check_free_sector: check if a free sector is actually FREE,
 352  *      i.e. All 0xff in data and oob area.
 353  */
 354 static int check_free_sectors(struct INFTLrecord *inftl, unsigned int address,
 355         int len, int check_oob)
 356 {
 357         u8 buf[SECTORSIZE + inftl->mbd.mtd->oobsize];
 358         struct mtd_info *mtd = inftl->mbd.mtd;
 359         size_t retlen;
 360         int i;
 361
 362         for (i = 0; i < len; i += SECTORSIZE) {
 363                 if (mtd->read(mtd, address, SECTORSIZE, &retlen, buf))
 364                         return -1;
 365                 if (memcmpb(buf, 0xff, SECTORSIZE) != 0)
 366                         return -1;
 367
 368                 if (check_oob) {
 369                         if(inftl_read_oob(mtd, address, mtd->oobsize,
 370                                           &retlen, &buf[SECTORSIZE]) < 0)
 371                                 return -1;
 372                         if (memcmpb(buf + SECTORSIZE, 0xff, mtd->oobsize) != 0)
 373                                 return -1;
 374                 }
 375                 address += SECTORSIZE;
 376         }
 377
 378         return 0;
 379 }
 380
 381 /*
 382  * INFTL_format: format a Erase Unit by erasing ALL Erase Zones in the Erase
 383  *               Unit and Update INFTL metadata. Each erase operation is
 384  *               checked with check_free_sectors.
 385  *
 386  * Return: 0 when succeed, -1 on error.
 387  *
 388  * ToDo: 1. Is it neceressary to check_free_sector after erasing ??
 389  */
 390 int INFTL_formatblock(struct INFTLrecord *inftl, int block)
 391 {
 392         size_t retlen;
 393         struct inftl_unittail uci;
 394         struct erase_info *instr = &inftl->instr;
 395         struct mtd_info *mtd = inftl->mbd.mtd;
 396         int physblock;
 397
 398         DEBUG(MTD_DEBUG_LEVEL3, "INFTL: INFTL_formatblock(inftl=%p,"
 399                 "block=%d)\n", inftl, block);
 400
 401         memset(instr, 0, sizeof(struct erase_info));
 402
 403         /* FIXME: Shouldn't we be setting the 'discarded' flag to zero
 404            _first_? */
 405
 406         /* Use async erase interface, test return code */
 407         instr->mtd = inftl->mbd.mtd;
 408         instr->addr = block * inftl->EraseSize;
 409         instr->len = inftl->mbd.mtd->erasesize;
 410         /* Erase one physical eraseblock at a time, even though the NAND api
 411            allows us to group them.  This way we if we have a failure, we can
 412            mark only the failed block in the bbt. */
 413         for (physblock = 0; physblock < inftl->EraseSize;
 414              physblock += instr->len, instr->addr += instr->len) {
 415                 mtd->erase(inftl->mbd.mtd, instr);
 416
 417                 if (instr->state == MTD_ERASE_FAILED) {
 418                         printk(KERN_WARNING "INFTL: error while formatting block %d\n",
 419                                 block);
 420                         goto fail;
 421                 }
 422
 423                 /*
 424                  * Check the "freeness" of Erase Unit before updating metadata.
 425                  * FixMe: is this check really necessary? Since we have check
 426                  * the return code after the erase operation.
 427                  */
 428                 if (check_free_sectors(inftl, instr->addr, instr->len, 1) != 0)
 429                         goto fail;
 430         }
 431
 432         uci.EraseMark = cpu_to_le16(ERASE_MARK);
 433         uci.EraseMark1 = cpu_to_le16(ERASE_MARK);
 434         uci.Reserved[0] = 0;
 435         uci.Reserved[1] = 0;
 436         uci.Reserved[2] = 0;
 437         uci.Reserved[3] = 0;
 438         instr->addr = block * inftl->EraseSize + SECTORSIZE * 2;
 439         if (inftl_write_oob(mtd, instr->addr + 8, 8, &retlen, (char *)&uci) < 0)
 440                 goto fail;
 441         return 0;
 442 fail:
 443         /* could not format, update the bad block table (caller is responsible
 444            for setting the PUtable to BLOCK_RESERVED on failure) */
 445         inftl->mbd.mtd->block_markbad(inftl->mbd.mtd, instr->addr);
 446         return -1;
 447 }
 448
 449 /*
 450  * format_chain: Format an invalid Virtual Unit chain. It frees all the Erase
 451  *      Units in a Virtual Unit Chain, i.e. all the units are disconnected.
 452  *
 453  *      Since the chain is invalid then we will have to erase it from its
 454  *      head (normally for INFTL we go from the oldest). But if it has a
 455  *      loop then there is no oldest...
 456  */
 457 static void format_chain(struct INFTLrecord *inftl, unsigned int first_block)
 458 {
 459         unsigned int block = first_block, block1;
 460
 461         printk(KERN_WARNING "INFTL: formatting chain at block %d\n",
 462                 first_block);
 463
 464         for (;;) {
 465                 block1 = inftl->PUtable[block];
 466
 467                 printk(KERN_WARNING "INFTL: formatting block %d\n", block);
 468                 if (INFTL_formatblock(inftl, block) < 0) {
 469                         /*
 470                          * Cannot format !!!! Mark it as Bad Unit,
 471                          */
 472                         inftl->PUtable[block] = BLOCK_RESERVED;
 473                 } else {
 474                         inftl->PUtable[block] = BLOCK_FREE;
 475                 }
 476
 477                 /* Goto next block on the chain */
 478                 block = block1;
 479
 480                 if (block == BLOCK_NIL || block >= inftl->lastEUN)
 481                         break;
 482         }
 483 }
 484
 485 void INFTL_dumptables(struct INFTLrecord *s)
 486 {
 487         int i;
 488
 489         printk("-------------------------------------------"
 490                 "----------------------------------\n");
 491
 492         printk("VUtable[%d] ->", s->nb_blocks);
 493         for (i = 0; i < s->nb_blocks; i++) {
 494                 if ((i % 8) == 0)
 495                         printk("\n%04x: ", i);
 496                 printk("%04x ", s->VUtable[i]);
 497         }
 498
 499         printk("\n-------------------------------------------"
 500                 "----------------------------------\n");
 501
 502         printk("PUtable[%d-%d=%d] ->", s->firstEUN, s->lastEUN, s->nb_blocks);
 503         for (i = 0; i <= s->lastEUN; i++) {
 504                 if ((i % 8) == 0)
 505                         printk("\n%04x: ", i);
 506                 printk("%04x ", s->PUtable[i]);
 507         }
 508
 509         printk("\n-------------------------------------------"
 510                 "----------------------------------\n");
 511
 512         printk("INFTL ->\n"
 513                 "  EraseSize       = %d\n"
 514                 "  h/s/c           = %d/%d/%d\n"
 515                 "  numvunits       = %d\n"
 516                 "  firstEUN        = %d\n"
 517                 "  lastEUN         = %d\n"
 518                 "  numfreeEUNs     = %d\n"
 519                 "  LastFreeEUN     = %d\n"
 520                 "  nb_blocks       = %d\n"
 521                 "  nb_boot_blocks  = %d",
 522                 s->EraseSize, s->heads, s->sectors, s->cylinders,
 523                 s->numvunits, s->firstEUN, s->lastEUN, s->numfreeEUNs,
 524                 s->LastFreeEUN, s->nb_blocks, s->nb_boot_blocks);
 525
 526         printk("\n-------------------------------------------"
 527                 "----------------------------------\n");
 528 }
 529
 530 void INFTL_dumpVUchains(struct INFTLrecord *s)
 531 {
 532         int logical, block, i;
 533
 534         printk("-------------------------------------------"
 535                 "----------------------------------\n");
 536
 537         printk("INFTL Virtual Unit Chains:\n");
 538         for (logical = 0; logical < s->nb_blocks; logical++) {
 539                 block = s->VUtable[logical];
 540                 if (block > s->nb_blocks)
 541                         continue;
 542                 printk("  LOGICAL %d --> %d ", logical, block);
 543                 for (i = 0; i < s->nb_blocks; i++) {
 544                         if (s->PUtable[block] == BLOCK_NIL)
 545                                 break;
 546                         block = s->PUtable[block];
 547                         printk("%d ", block);
 548                 }
 549                 printk("\n");
 550         }
 551
 552         printk("-------------------------------------------"
 553                 "----------------------------------\n");
 554 }
 555
 556 int INFTL_mount(struct INFTLrecord *s)
 557 {
 558         struct mtd_info *mtd = s->mbd.mtd;
 559         unsigned int block, first_block, prev_block, last_block;
 560         unsigned int first_logical_block, logical_block, erase_mark;
 561         int chain_length, do_format_chain;
 562         struct inftl_unithead1 h0;
 563         struct inftl_unittail h1;
 564         size_t retlen;
 565         int i;
 566         u8 *ANACtable, ANAC;
 567
 568         DEBUG(MTD_DEBUG_LEVEL3, "INFTL: INFTL_mount(inftl=%p)\n", s);
 569
 570         /* Search for INFTL MediaHeader and Spare INFTL Media Header */
 571         if (find_boot_record(s) < 0) {
 572                 printk(KERN_WARNING "INFTL: could not find valid boot record?\n");
 573                 return -ENXIO;
 574         }
 575
 576         /* Init the logical to physical table */
 577         for (i = 0; i < s->nb_blocks; i++)
 578                 s->VUtable[i] = BLOCK_NIL;
 579
 580         logical_block = block = BLOCK_NIL;
 581
 582         /* Temporary buffer to store ANAC numbers. */
 583         ANACtable = kmalloc(s->nb_blocks * sizeof(u8), GFP_KERNEL);
 584         if (!ANACtable) {
 585                 printk(KERN_WARNING "INFTL: allocation of ANACtable "
 586                                 "failed (%zd bytes)\n",
 587                                 s->nb_blocks * sizeof(u8));
 588                 return -ENOMEM;
 589         }
 590         memset(ANACtable, 0, s->nb_blocks);
 591
 592         /*
 593          * First pass is to explore each physical unit, and construct the
 594          * virtual chains that exist (newest physical unit goes into VUtable).
 595          * Any block that is in any way invalid will be left in the
 596          * NOTEXPLORED state. Then at the end we will try to format it and
 597          * mark it as free.
 598          */
 599         DEBUG(MTD_DEBUG_LEVEL3, "INFTL: pass 1, explore each unit\n");
 600         for (first_block = s->firstEUN; first_block <= s->lastEUN; first_block++) {
 601                 if (s->PUtable[first_block] != BLOCK_NOTEXPLORED)
 602                         continue;
 603
 604                 do_format_chain = 0;
 605                 first_logical_block = BLOCK_NIL;
 606                 last_block = BLOCK_NIL;
 607                 block = first_block;
 608
 609                 for (chain_length = 0; ; chain_length++) {
 610
 611                         if ((chain_length == 0) &&
 612                             (s->PUtable[block] != BLOCK_NOTEXPLORED)) {
 613                                 /* Nothing to do here, onto next block */
 614                                 break;
 615                         }
 616
 617                         if (inftl_read_oob(mtd, block * s->EraseSize + 8,
 618                                            8, &retlen, (char *)&h0) < 0 ||
 619                             inftl_read_oob(mtd, block * s->EraseSize +
 620                                            2 * SECTORSIZE + 8, 8, &retlen,
 621                                            (char *)&h1) < 0) {
 622                                 /* Should never happen? */
 623                                 do_format_chain++;
 624                                 break;
 625                         }
 626
 627                         logical_block = le16_to_cpu(h0.virtualUnitNo);
 628                         prev_block = le16_to_cpu(h0.prevUnitNo);
 629                         erase_mark = le16_to_cpu((h1.EraseMark | h1.EraseMark1));
 630                         ANACtable[block] = h0.ANAC;
 631
 632                         /* Previous block is relative to start of Partition */
 633                         if (prev_block < s->nb_blocks)
 634                                 prev_block += s->firstEUN;
 635
 636                         /* Already explored partial chain? */
 637                         if (s->PUtable[block] != BLOCK_NOTEXPLORED) {
 638                                 /* Check if chain for this logical */
 639                                 if (logical_block == first_logical_block) {
 640                                         if (last_block != BLOCK_NIL)
 641                                                 s->PUtable[last_block] = block;
 642                                 }
 643                                 break;
 644                         }
 645
 646                         /* Check for invalid block */
 647                         if (erase_mark != ERASE_MARK) {
 648                                 printk(KERN_WARNING "INFTL: corrupt block %d "
 649                                         "in chain %d, chain length %d, erase "
 650                                         "mark 0x%x?\n", block, first_block,
 651                                         chain_length, erase_mark);
 652                                 /*
 653                                  * Assume end of chain, probably incomplete
 654                                  * fold/erase...
 655                                  */
 656                                 if (chain_length == 0)
 657                                         do_format_chain++;
 658                                 break;
 659                         }
 660
 661                         /* Check for it being free already then... */
 662                         if ((logical_block == BLOCK_FREE) ||
 663                             (logical_block == BLOCK_NIL)) {
 664                                 s->PUtable[block] = BLOCK_FREE;
 665                                 break;
 666                         }
 667
 668                         /* Sanity checks on block numbers */
 669                         if ((logical_block >= s->nb_blocks) ||
 670                             ((prev_block >= s->nb_blocks) &&
 671                              (prev_block != BLOCK_NIL))) {
 672                                 if (chain_length > 0) {
 673                                         printk(KERN_WARNING "INFTL: corrupt "
 674                                                 "block %d in chain %d?\n",
 675                                                 block, first_block);
 676                                         do_format_chain++;
 677                                 }
 678                                 break;
 679                         }
 680
 681                         if (first_logical_block == BLOCK_NIL) {
 682                                 first_logical_block = logical_block;
 683                         } else {
 684                                 if (first_logical_block != logical_block) {
 685                                         /* Normal for folded chain... */
 686                                         break;
 687                                 }
 688                         }
 689
 690                         /*
 691                          * Current block is valid, so if we followed a virtual
 692                          * chain to get here then we can set the previous
 693                          * block pointer in our PUtable now. Then move onto
 694                          * the previous block in the chain.
 695                          */
 696                         s->PUtable[block] = BLOCK_NIL;
 697                         if (last_block != BLOCK_NIL)
 698                                 s->PUtable[last_block] = block;
 699                         last_block = block;
 700                         block = prev_block;
 701
 702                         /* Check for end of chain */
 703                         if (block == BLOCK_NIL)
 704                                 break;
 705
 706                         /* Validate next block before following it... */
 707                         if (block > s->lastEUN) {
 708                                 printk(KERN_WARNING "INFTL: invalid previous "
 709                                         "block %d in chain %d?\n", block,
 710                                         first_block);
 711                                 do_format_chain++;
 712                                 break;
 713                         }
 714                 }
 715
 716                 if (do_format_chain) {
 717                         format_chain(s, first_block);
 718                         continue;
 719                 }
 720
 721                 /*
 722                  * Looks like a valid chain then. It may not really be the
 723                  * newest block in the chain, but it is the newest we have
 724                  * found so far. We might update it in later iterations of
 725                  * this loop if we find something newer.
 726                  */
 727                 s->VUtable[first_logical_block] = first_block;
 728                 logical_block = BLOCK_NIL;
 729         }
 730
 731 #ifdef CONFIG_MTD_DEBUG_VERBOSE
 732         if (CONFIG_MTD_DEBUG_VERBOSE >= 2)
 733                 INFTL_dumptables(s);
 734 #endif
 735
 736         /*
 737          * Second pass, check for infinite loops in chains. These are
 738          * possible because we don't update the previous pointers when
 739          * we fold chains. No big deal, just fix them up in PUtable.
 740          */
 741         DEBUG(MTD_DEBUG_LEVEL3, "INFTL: pass 2, validate virtual chains\n");
 742         for (logical_block = 0; logical_block < s->numvunits; logical_block++) {
 743                 block = s->VUtable[logical_block];
 744                 last_block = BLOCK_NIL;
 745
 746                 /* Check for free/reserved/nil */
 747                 if (block >= BLOCK_RESERVED)
 748                         continue;
 749
 750                 ANAC = ANACtable[block];
 751                 for (i = 0; i < s->numvunits; i++) {
 752                         if (s->PUtable[block] == BLOCK_NIL)
 753                                 break;
 754                         if (s->PUtable[block] > s->lastEUN) {
 755                                 printk(KERN_WARNING "INFTL: invalid prev %d, "
 756                                         "in virtual chain %d\n",
 757                                         s->PUtable[block], logical_block);
 758                                 s->PUtable[block] = BLOCK_NIL;
 759
 760                         }
 761                         if (ANACtable[block] != ANAC) {
 762                                 /*
 763                                  * Chain must point back to itself. This is ok,
 764                                  * but we will need adjust the tables with this
 765                                  * newest block and oldest block.
 766                                  */
 767                                 s->VUtable[logical_block] = block;
 768                                 s->PUtable[last_block] = BLOCK_NIL;
 769                                 break;
 770                         }
 771
 772                         ANAC--;
 773                         last_block = block;
 774                         block = s->PUtable[block];
 775                 }
 776
 777                 if (i >= s->nb_blocks) {
 778                         /*
 779                          * Uhoo, infinite chain with valid ANACS!
 780                          * Format whole chain...
 781                          */
 782                         format_chain(s, first_block);
 783                 }
 784         }
 785
 786 #ifdef CONFIG_MTD_DEBUG_VERBOSE
 787         if (CONFIG_MTD_DEBUG_VERBOSE >= 2)
 788                 INFTL_dumptables(s);
 789         if (CONFIG_MTD_DEBUG_VERBOSE >= 2)
 790                 INFTL_dumpVUchains(s);
 791 #endif
 792
 793         /*
 794          * Third pass, format unreferenced blocks and init free block count.
 795          */
 796         s->numfreeEUNs = 0;
 797         s->LastFreeEUN = BLOCK_NIL;
 798
 799         DEBUG(MTD_DEBUG_LEVEL3, "INFTL: pass 3, format unused blocks\n");
 800         for (block = s->firstEUN; block <= s->lastEUN; block++) {
 801                 if (s->PUtable[block] == BLOCK_NOTEXPLORED) {
 802                         printk("INFTL: unreferenced block %d, formatting it\n",
 803                                 block);
 804                         if (INFTL_formatblock(s, block) < 0)
 805                                 s->PUtable[block] = BLOCK_RESERVED;
 806                         else
 807                                 s->PUtable[block] = BLOCK_FREE;
 808                 }
 809                 if (s->PUtable[block] == BLOCK_FREE) {
 810                         s->numfreeEUNs++;
 811                         if (s->LastFreeEUN == BLOCK_NIL)
 812                                 s->LastFreeEUN = block;
 813                 }
 814         }
 815
 816         kfree(ANACtable);
 817         return 0;
 818 }