drivers/mtd/rfd_ftl.c

   1 /*
   2  * rfd_ftl.c -- resident flash disk (flash translation layer)
   3  *
   4  * Copyright (C) 2005  Sean Young <sean@mess.org>
   5  *
   6  * This type of flash translation layer (FTL) is used by the Embedded BIOS
   7  * by General Software. It is known as the Resident Flash Disk (RFD), see:
   8  *
   9  *      http://www.gensw.com/pages/prod/bios/rfd.htm
  10  *
  11  * based on ftl.c
  12  */
  13
  14 #include <linux/hdreg.h>
  15 #include <linux/init.h>
  16 #include <linux/mtd/blktrans.h>
  17 #include <linux/mtd/mtd.h>
  18 #include <linux/vmalloc.h>
  19 #include <linux/slab.h>
  20 #include <linux/jiffies.h>
  21
  22 #include <asm/types.h>
  23
  24 #define const_cpu_to_le16       __constant_cpu_to_le16
  25
  26 static int block_size = 0;
  27 module_param(block_size, int, 0);
  28 MODULE_PARM_DESC(block_size, "Block size to use by RFD, defaults to erase unit size");
  29
  30 #define PREFIX "rfd_ftl: "
  31
  32 /* This major has been assigned by device@lanana.org */
  33 #ifndef RFD_FTL_MAJOR
  34 #define RFD_FTL_MAJOR           256
  35 #endif
  36
  37 /* Maximum number of partitions in an FTL region */
  38 #define PART_BITS               4
  39
  40 /* An erase unit should start with this value */
  41 #define RFD_MAGIC               0x9193
  42
  43 /* the second value is 0xffff or 0xffc8; function unknown */
  44
  45 /* the third value is always 0xffff, ignored */
  46
  47 /* next is an array of mapping for each corresponding sector */
  48 #define HEADER_MAP_OFFSET       3
  49 #define SECTOR_DELETED          0x0000
  50 #define SECTOR_ZERO             0xfffe
  51 #define SECTOR_FREE             0xffff
  52
  53 #define SECTOR_SIZE             512
  54
  55 #define SECTORS_PER_TRACK       63
  56
  57 struct block {
  58         enum {
  59                 BLOCK_OK,
  60                 BLOCK_ERASING,
  61                 BLOCK_ERASED,
  62                 BLOCK_UNUSED,
  63                 BLOCK_FAILED
  64         } state;
  65         int free_sectors;
  66         int used_sectors;
  67         int erases;
  68         u_long offset;
  69 };
  70
  71 struct partition {
  72         struct mtd_blktrans_dev mbd;
  73
  74         u_int block_size;               /* size of erase unit */
  75         u_int total_blocks;             /* number of erase units */
  76         u_int header_sectors_per_block; /* header sectors in erase unit */
  77         u_int data_sectors_per_block;   /* data sectors in erase unit */
  78         u_int sector_count;             /* sectors in translated disk */
  79         u_int header_size;              /* bytes in header sector */
  80         int reserved_block;             /* block next up for reclaim */
  81         int current_block;              /* block to write to */
  82         u16 *header_cache;              /* cached header */
  83
  84         int is_reclaiming;
  85         int cylinders;
  86         int errors;
  87         u_long *sector_map;
  88         struct block *blocks;
  89 };
  90
  91 static int rfd_ftl_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf);
  92
  93 static int build_block_map(struct partition *part, int block_no)
  94 {
  95         struct block *block = &part->blocks[block_no];
  96         int i;
  97
  98         block->offset = part->block_size * block_no;
  99
 100         if (le16_to_cpu(part->header_cache[0]) != RFD_MAGIC) {
 101                 block->state = BLOCK_UNUSED;
 102                 return -ENOENT;
 103         }
 104
 105         block->state = BLOCK_OK;
 106
 107         for (i=0; i<part->data_sectors_per_block; i++) {
 108                 u16 entry;
 109
 110                 entry = le16_to_cpu(part->header_cache[HEADER_MAP_OFFSET + i]);
 111
 112                 if (entry == SECTOR_DELETED)
 113                         continue;
 114
 115                 if (entry == SECTOR_FREE) {
 116                         block->free_sectors++;
 117                         continue;
 118                 }
 119
 120                 if (entry == SECTOR_ZERO)
 121                         entry = 0;
 122
 123                 if (entry >= part->sector_count) {
 124                         printk(KERN_WARNING PREFIX
 125                                 "'%s': unit #%d: entry %d corrupt, "
 126                                 "sector %d out of range\n",
 127                                 part->mbd.mtd->name, block_no, i, entry);
 128                         continue;
 129                 }
 130
 131                 if (part->sector_map[entry] != -1) {
 132                         printk(KERN_WARNING PREFIX
 133                                 "'%s': more than one entry for sector %d\n",
 134                                 part->mbd.mtd->name, entry);
 135                         part->errors = 1;
 136                         continue;
 137                 }
 138
 139                 part->sector_map[entry] = block->offset +
 140                         (i + part->header_sectors_per_block) * SECTOR_SIZE;
 141
 142                 block->used_sectors++;
 143         }
 144
 145         if (block->free_sectors == part->data_sectors_per_block)
 146                 part->reserved_block = block_no;
 147
 148         return 0;
 149 }
 150
 151 static int scan_header(struct partition *part)
 152 {
 153         int sectors_per_block;
 154         int i, rc = -ENOMEM;
 155         int blocks_found;
 156         size_t retlen;
 157
 158         sectors_per_block = part->block_size / SECTOR_SIZE;
 159         part->total_blocks = (u32)part->mbd.mtd->size / part->block_size;
 160
 161         if (part->total_blocks < 2)
 162                 return -ENOENT;
 163
 164         /* each erase block has three bytes header, followed by the map */
 165         part->header_sectors_per_block =
 166                         ((HEADER_MAP_OFFSET + sectors_per_block) *
 167                         sizeof(u16) + SECTOR_SIZE - 1) / SECTOR_SIZE;
 168
 169         part->data_sectors_per_block = sectors_per_block -
 170                         part->header_sectors_per_block;
 171
 172         part->header_size = (HEADER_MAP_OFFSET +
 173                         part->data_sectors_per_block) * sizeof(u16);
 174
 175         part->cylinders = (part->data_sectors_per_block *
 176                         (part->total_blocks - 1) - 1) / SECTORS_PER_TRACK;
 177
 178         part->sector_count = part->cylinders * SECTORS_PER_TRACK;
 179
 180         part->current_block = -1;
 181         part->reserved_block = -1;
 182         part->is_reclaiming = 0;
 183
 184         part->header_cache = kmalloc(part->header_size, GFP_KERNEL);
 185         if (!part->header_cache)
 186                 goto err;
 187
 188         part->blocks = kcalloc(part->total_blocks, sizeof(struct block),
 189                         GFP_KERNEL);
 190         if (!part->blocks)
 191                 goto err;
 192
 193         part->sector_map = vmalloc(part->sector_count * sizeof(u_long));
 194         if (!part->sector_map) {
 195                 printk(KERN_ERR PREFIX "'%s': unable to allocate memory for "
 196                         "sector map", part->mbd.mtd->name);
 197                 goto err;
 198         }
 199
 200         for (i=0; i<part->sector_count; i++)
 201                 part->sector_map[i] = -1;
 202
 203         for (i=0, blocks_found=0; i<part->total_blocks; i++) {
 204                 rc = part->mbd.mtd->read(part->mbd.mtd,
 205                                 i * part->block_size, part->header_size,
 206                                 &retlen, (u_char*)part->header_cache);
 207
 208                 if (!rc && retlen != part->header_size)
 209                         rc = -EIO;
 210
 211                 if (rc)
 212                         goto err;
 213
 214                 if (!build_block_map(part, i))
 215                         blocks_found++;
 216         }
 217
 218         if (blocks_found == 0) {
 219                 printk(KERN_NOTICE PREFIX "no RFD magic found in '%s'\n",
 220                                 part->mbd.mtd->name);
 221                 rc = -ENOENT;
 222                 goto err;
 223         }
 224
 225         if (part->reserved_block == -1) {
 226                 printk(KERN_WARNING PREFIX "'%s': no empty erase unit found\n",
 227                                 part->mbd.mtd->name);
 228
 229                 part->errors = 1;
 230         }
 231
 232         return 0;
 233
 234 err:
 235         vfree(part->sector_map);
 236         kfree(part->header_cache);
 237         kfree(part->blocks);
 238
 239         return rc;
 240 }
 241
 242 static int rfd_ftl_readsect(struct mtd_blktrans_dev *dev, u_long sector, char *buf)
 243 {
 244         struct partition *part = (struct partition*)dev;
 245         u_long addr;
 246         size_t retlen;
 247         int rc;
 248
 249         if (sector >= part->sector_count)
 250                 return -EIO;
 251
 252         addr = part->sector_map[sector];
 253         if (addr != -1) {
 254                 rc = part->mbd.mtd->read(part->mbd.mtd, addr, SECTOR_SIZE,
 255                                                 &retlen, (u_char*)buf);
 256                 if (!rc && retlen != SECTOR_SIZE)
 257                         rc = -EIO;
 258
 259                 if (rc) {
 260                         printk(KERN_WARNING PREFIX "error reading '%s' at "
 261                                 "0x%lx\n", part->mbd.mtd->name, addr);
 262                         return rc;
 263                 }
 264         } else
 265                 memset(buf, 0, SECTOR_SIZE);
 266
 267         return 0;
 268 }
 269
 270 static void erase_callback(struct erase_info *erase)
 271 {
 272         struct partition *part;
 273         u16 magic;
 274         int i, rc;
 275         size_t retlen;
 276
 277         part = (struct partition*)erase->priv;
 278
 279         i = (u32)erase->addr / part->block_size;
 280         if (i >= part->total_blocks || part->blocks[i].offset != erase->addr ||
 281             erase->addr > UINT_MAX) {
 282                 printk(KERN_ERR PREFIX "erase callback for unknown offset %llx "
 283                                 "on '%s'\n", (unsigned long long)erase->addr, part->mbd.mtd->name);
 284                 return;
 285         }
 286
 287         if (erase->state != MTD_ERASE_DONE) {
 288                 printk(KERN_WARNING PREFIX "erase failed at 0x%llx on '%s', "
 289                                 "state %d\n", (unsigned long long)erase->addr,
 290                                 part->mbd.mtd->name, erase->state);
 291
 292                 part->blocks[i].state = BLOCK_FAILED;
 293                 part->blocks[i].free_sectors = 0;
 294                 part->blocks[i].used_sectors = 0;
 295
 296                 kfree(erase);
 297
 298                 return;
 299         }
 300
 301         magic = const_cpu_to_le16(RFD_MAGIC);
 302
 303         part->blocks[i].state = BLOCK_ERASED;
 304         part->blocks[i].free_sectors = part->data_sectors_per_block;
 305         part->blocks[i].used_sectors = 0;
 306         part->blocks[i].erases++;
 307
 308         rc = part->mbd.mtd->write(part->mbd.mtd,
 309                 part->blocks[i].offset, sizeof(magic), &retlen,
 310                 (u_char*)&magic);
 311
 312         if (!rc && retlen != sizeof(magic))
 313                 rc = -EIO;
 314
 315         if (rc) {
 316                 printk(KERN_ERR PREFIX "'%s': unable to write RFD "
 317                                 "header at 0x%lx\n",
 318                                 part->mbd.mtd->name,
 319                                 part->blocks[i].offset);
 320                 part->blocks[i].state = BLOCK_FAILED;
 321         }
 322         else
 323                 part->blocks[i].state = BLOCK_OK;
 324
 325         kfree(erase);
 326 }
 327
 328 static int erase_block(struct partition *part, int block)
 329 {
 330         struct erase_info *erase;
 331         int rc = -ENOMEM;
 332
 333         erase = kmalloc(sizeof(struct erase_info), GFP_KERNEL);
 334         if (!erase)
 335                 goto err;
 336
 337         erase->mtd = part->mbd.mtd;
 338         erase->callback = erase_callback;
 339         erase->addr = part->blocks[block].offset;
 340         erase->len = part->block_size;
 341         erase->priv = (u_long)part;
 342
 343         part->blocks[block].state = BLOCK_ERASING;
 344         part->blocks[block].free_sectors = 0;
 345
 346         rc = part->mbd.mtd->erase(part->mbd.mtd, erase);
 347
 348         if (rc) {
 349                 printk(KERN_ERR PREFIX "erase of region %llx,%llx on '%s' "
 350                                 "failed\n", (unsigned long long)erase->addr,
 351                                 (unsigned long long)erase->len, part->mbd.mtd->name);
 352                 kfree(erase);
 353         }
 354
 355 err:
 356         return rc;
 357 }
 358
 359 static int move_block_contents(struct partition *part, int block_no, u_long *old_sector)
 360 {
 361         void *sector_data;
 362         u16 *map;
 363         size_t retlen;
 364         int i, rc = -ENOMEM;
 365
 366         part->is_reclaiming = 1;
 367
 368         sector_data = kmalloc(SECTOR_SIZE, GFP_KERNEL);
 369         if (!sector_data)
 370                 goto err3;
 371
 372         map = kmalloc(part->header_size, GFP_KERNEL);
 373         if (!map)
 374                 goto err2;
 375
 376         rc = part->mbd.mtd->read(part->mbd.mtd,
 377                 part->blocks[block_no].offset, part->header_size,
 378                 &retlen, (u_char*)map);
 379
 380         if (!rc && retlen != part->header_size)
 381                 rc = -EIO;
 382
 383         if (rc) {
 384                 printk(KERN_ERR PREFIX "error reading '%s' at "
 385                         "0x%lx\n", part->mbd.mtd->name,
 386                         part->blocks[block_no].offset);
 387
 388                 goto err;
 389         }
 390
 391         for (i=0; i<part->data_sectors_per_block; i++) {
 392                 u16 entry = le16_to_cpu(map[HEADER_MAP_OFFSET + i]);
 393                 u_long addr;
 394
 395
 396                 if (entry == SECTOR_FREE || entry == SECTOR_DELETED)
 397                         continue;
 398
 399                 if (entry == SECTOR_ZERO)
 400                         entry = 0;
 401
 402                 /* already warned about and ignored in build_block_map() */
 403                 if (entry >= part->sector_count)
 404                         continue;
 405
 406                 addr = part->blocks[block_no].offset +
 407                         (i + part->header_sectors_per_block) * SECTOR_SIZE;
 408
 409                 if (*old_sector == addr) {
 410                         *old_sector = -1;
 411                         if (!part->blocks[block_no].used_sectors--) {
 412                                 rc = erase_block(part, block_no);
 413                                 break;
 414                         }
 415                         continue;
 416                 }
 417                 rc = part->mbd.mtd->read(part->mbd.mtd, addr,
 418                         SECTOR_SIZE, &retlen, sector_data);
 419
 420                 if (!rc && retlen != SECTOR_SIZE)
 421                         rc = -EIO;
 422
 423                 if (rc) {
 424                         printk(KERN_ERR PREFIX "'%s': Unable to "
 425                                 "read sector for relocation\n",
 426                                 part->mbd.mtd->name);
 427
 428                         goto err;
 429                 }
 430
 431                 rc = rfd_ftl_writesect((struct mtd_blktrans_dev*)part,
 432                                 entry, sector_data);
 433
 434                 if (rc)
 435                         goto err;
 436         }
 437
 438 err:
 439         kfree(map);
 440 err2:
 441         kfree(sector_data);
 442 err3:
 443         part->is_reclaiming = 0;
 444
 445         return rc;
 446 }
 447
 448 static int reclaim_block(struct partition *part, u_long *old_sector)
 449 {
 450         int block, best_block, score, old_sector_block;
 451         int rc;
 452
 453         /* we have a race if sync doesn't exist */
 454         if (part->mbd.mtd->sync)
 455                 part->mbd.mtd->sync(part->mbd.mtd);
 456
 457         score = 0x7fffffff; /* MAX_INT */
 458         best_block = -1;
 459         if (*old_sector != -1)
 460                 old_sector_block = *old_sector / part->block_size;
 461         else
 462                 old_sector_block = -1;
 463
 464         for (block=0; block<part->total_blocks; block++) {
 465                 int this_score;
 466
 467                 if (block == part->reserved_block)
 468                         continue;
 469
 470                 /*
 471                  * Postpone reclaiming if there is a free sector as
 472                  * more removed sectors is more efficient (have to move
 473                  * less).
 474                  */
 475                 if (part->blocks[block].free_sectors)
 476                         return 0;
 477
 478                 this_score = part->blocks[block].used_sectors;
 479
 480                 if (block == old_sector_block)
 481                         this_score--;
 482                 else {
 483                         /* no point in moving a full block */
 484                         if (part->blocks[block].used_sectors ==
 485                                         part->data_sectors_per_block)
 486                                 continue;
 487                 }
 488
 489                 this_score += part->blocks[block].erases;
 490
 491                 if (this_score < score) {
 492                         best_block = block;
 493                         score = this_score;
 494                 }
 495         }
 496
 497         if (best_block == -1)
 498                 return -ENOSPC;
 499
 500         part->current_block = -1;
 501         part->reserved_block = best_block;
 502
 503         pr_debug("reclaim_block: reclaiming block #%d with %d used "
 504                  "%d free sectors\n", best_block,
 505                  part->blocks[best_block].used_sectors,
 506                  part->blocks[best_block].free_sectors);
 507
 508         if (part->blocks[best_block].used_sectors)
 509                 rc = move_block_contents(part, best_block, old_sector);
 510         else
 511                 rc = erase_block(part, best_block);
 512
 513         return rc;
 514 }
 515
 516 /*
 517  * IMPROVE: It would be best to choose the block with the most deleted sectors,
 518  * because if we fill that one up first it'll have the most chance of having
 519  * the least live sectors at reclaim.
 520  */
 521 static int find_free_block(struct partition *part)
 522 {
 523         int block, stop;
 524
 525         block = part->current_block == -1 ?
 526                         jiffies % part->total_blocks : part->current_block;
 527         stop = block;
 528
 529         do {
 530                 if (part->blocks[block].free_sectors &&
 531                                 block != part->reserved_block)
 532                         return block;
 533
 534                 if (part->blocks[block].state == BLOCK_UNUSED)
 535                         erase_block(part, block);
 536
 537                 if (++block >= part->total_blocks)
 538                         block = 0;
 539
 540         } while (block != stop);
 541
 542         return -1;
 543 }
 544
 545 static int find_writable_block(struct partition *part, u_long *old_sector)
 546 {
 547         int rc, block;
 548         size_t retlen;
 549
 550         block = find_free_block(part);
 551
 552         if (block == -1) {
 553                 if (!part->is_reclaiming) {
 554                         rc = reclaim_block(part, old_sector);
 555                         if (rc)
 556                                 goto err;
 557
 558                         block = find_free_block(part);
 559                 }
 560
 561                 if (block == -1) {
 562                         rc = -ENOSPC;
 563                         goto err;
 564                 }
 565         }
 566
 567         rc = part->mbd.mtd->read(part->mbd.mtd, part->blocks[block].offset,
 568                 part->header_size, &retlen, (u_char*)part->header_cache);
 569
 570         if (!rc && retlen != part->header_size)
 571                 rc = -EIO;
 572
 573         if (rc) {
 574                 printk(KERN_ERR PREFIX "'%s': unable to read header at "
 575                                 "0x%lx\n", part->mbd.mtd->name,
 576                                 part->blocks[block].offset);
 577                 goto err;
 578         }
 579
 580         part->current_block = block;
 581
 582 err:
 583         return rc;
 584 }
 585
 586 static int mark_sector_deleted(struct partition *part, u_long old_addr)
 587 {
 588         int block, offset, rc;
 589         u_long addr;
 590         size_t retlen;
 591         u16 del = const_cpu_to_le16(SECTOR_DELETED);
 592
 593         block = old_addr / part->block_size;
 594         offset = (old_addr % part->block_size) / SECTOR_SIZE -
 595                 part->header_sectors_per_block;
 596
 597         addr = part->blocks[block].offset +
 598                         (HEADER_MAP_OFFSET + offset) * sizeof(u16);
 599         rc = part->mbd.mtd->write(part->mbd.mtd, addr,
 600                 sizeof(del), &retlen, (u_char*)&del);
 601
 602         if (!rc && retlen != sizeof(del))
 603                 rc = -EIO;
 604
 605         if (rc) {
 606                 printk(KERN_ERR PREFIX "error writing '%s' at "
 607                         "0x%lx\n", part->mbd.mtd->name, addr);
 608                 if (rc)
 609                         goto err;
 610         }
 611         if (block == part->current_block)
 612                 part->header_cache[offset + HEADER_MAP_OFFSET] = del;
 613
 614         part->blocks[block].used_sectors--;
 615
 616         if (!part->blocks[block].used_sectors &&
 617             !part->blocks[block].free_sectors)
 618                 rc = erase_block(part, block);
 619
 620 err:
 621         return rc;
 622 }
 623
 624 static int find_free_sector(const struct partition *part, const struct block *block)
 625 {
 626         int i, stop;
 627
 628         i = stop = part->data_sectors_per_block - block->free_sectors;
 629
 630         do {
 631                 if (le16_to_cpu(part->header_cache[HEADER_MAP_OFFSET + i])
 632                                 == SECTOR_FREE)
 633                         return i;
 634
 635                 if (++i == part->data_sectors_per_block)
 636                         i = 0;
 637         }
 638         while(i != stop);
 639
 640         return -1;
 641 }
 642
 643 static int do_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf, ulong *old_addr)
 644 {
 645         struct partition *part = (struct partition*)dev;
 646         struct block *block;
 647         u_long addr;
 648         int i;
 649         int rc;
 650         size_t retlen;
 651         u16 entry;
 652
 653         if (part->current_block == -1 ||
 654                 !part->blocks[part->current_block].free_sectors) {
 655
 656                 rc = find_writable_block(part, old_addr);
 657                 if (rc)
 658                         goto err;
 659         }
 660
 661         block = &part->blocks[part->current_block];
 662
 663         i = find_free_sector(part, block);
 664
 665         if (i < 0) {
 666                 rc = -ENOSPC;
 667                 goto err;
 668         }
 669
 670         addr = (i + part->header_sectors_per_block) * SECTOR_SIZE +
 671                 block->offset;
 672         rc = part->mbd.mtd->write(part->mbd.mtd,
 673                 addr, SECTOR_SIZE, &retlen, (u_char*)buf);
 674
 675         if (!rc && retlen != SECTOR_SIZE)
 676                 rc = -EIO;
 677
 678         if (rc) {
 679                 printk(KERN_ERR PREFIX "error writing '%s' at 0x%lx\n",
 680                                 part->mbd.mtd->name, addr);
 681                 if (rc)
 682                         goto err;
 683         }
 684
 685         part->sector_map[sector] = addr;
 686
 687         entry = cpu_to_le16(sector == 0 ? SECTOR_ZERO : sector);
 688
 689         part->header_cache[i + HEADER_MAP_OFFSET] = entry;
 690
 691         addr = block->offset + (HEADER_MAP_OFFSET + i) * sizeof(u16);
 692         rc = part->mbd.mtd->write(part->mbd.mtd, addr,
 693                         sizeof(entry), &retlen, (u_char*)&entry);
 694
 695         if (!rc && retlen != sizeof(entry))
 696                 rc = -EIO;
 697
 698         if (rc) {
 699                 printk(KERN_ERR PREFIX "error writing '%s' at 0x%lx\n",
 700                                 part->mbd.mtd->name, addr);
 701                 if (rc)
 702                         goto err;
 703         }
 704         block->used_sectors++;
 705         block->free_sectors--;
 706
 707 err:
 708         return rc;
 709 }
 710
 711 static int rfd_ftl_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf)
 712 {
 713         struct partition *part = (struct partition*)dev;
 714         u_long old_addr;
 715         int i;
 716         int rc = 0;
 717
 718         pr_debug("rfd_ftl_writesect(sector=0x%lx)\n", sector);
 719
 720         if (part->reserved_block == -1) {
 721                 rc = -EACCES;
 722                 goto err;
 723         }
 724
 725         if (sector >= part->sector_count) {
 726                 rc = -EIO;
 727                 goto err;
 728         }
 729
 730         old_addr = part->sector_map[sector];
 731
 732         for (i=0; i<SECTOR_SIZE; i++) {
 733                 if (!buf[i])
 734                         continue;
 735
 736                 rc = do_writesect(dev, sector, buf, &old_addr);
 737                 if (rc)
 738                         goto err;
 739                 break;
 740         }
 741
 742         if (i == SECTOR_SIZE)
 743                 part->sector_map[sector] = -1;
 744
 745         if (old_addr != -1)
 746                 rc = mark_sector_deleted(part, old_addr);
 747
 748 err:
 749         return rc;
 750 }
 751
 752 static int rfd_ftl_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
 753 {
 754         struct partition *part = (struct partition*)dev;
 755
 756         geo->heads = 1;
 757         geo->sectors = SECTORS_PER_TRACK;
 758         geo->cylinders = part->cylinders;
 759
 760         return 0;
 761 }
 762
 763 static void rfd_ftl_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
 764 {
 765         struct partition *part;
 766
 767         if (mtd->type != MTD_NORFLASH || mtd->size > UINT_MAX)
 768                 return;
 769
 770         part = kzalloc(sizeof(struct partition), GFP_KERNEL);
 771         if (!part)
 772                 return;
 773
 774         part->mbd.mtd = mtd;
 775
 776         if (block_size)
 777                 part->block_size = block_size;
 778         else {
 779                 if (!mtd->erasesize) {
 780                         printk(KERN_WARNING PREFIX "please provide block_size");
 781                         goto out;
 782                 } else
 783                         part->block_size = mtd->erasesize;
 784         }
 785
 786         if (scan_header(part) == 0) {
 787                 part->mbd.size = part->sector_count;
 788                 part->mbd.tr = tr;
 789                 part->mbd.devnum = -1;
 790                 if (!(mtd->flags & MTD_WRITEABLE))
 791                         part->mbd.readonly = 1;
 792                 else if (part->errors) {
 793                         printk(KERN_WARNING PREFIX "'%s': errors found, "
 794                                         "setting read-only\n", mtd->name);
 795                         part->mbd.readonly = 1;
 796                 }
 797
 798                 printk(KERN_INFO PREFIX "name: '%s' type: %d flags %x\n",
 799                                 mtd->name, mtd->type, mtd->flags);
 800
 801                 if (!add_mtd_blktrans_dev((void*)part))
 802                         return;
 803         }
 804 out:
 805         kfree(part);
 806 }
 807
 808 static void rfd_ftl_remove_dev(struct mtd_blktrans_dev *dev)
 809 {
 810         struct partition *part = (struct partition*)dev;
 811         int i;
 812
 813         for (i=0; i<part->total_blocks; i++) {
 814                 pr_debug("rfd_ftl_remove_dev:'%s': erase unit #%02d: %d erases\n",
 815                         part->mbd.mtd->name, i, part->blocks[i].erases);
 816         }
 817
 818         del_mtd_blktrans_dev(dev);
 819         vfree(part->sector_map);
 820         kfree(part->header_cache);
 821         kfree(part->blocks);
 822         kfree(part);
 823 }
 824
 825 static struct mtd_blktrans_ops rfd_ftl_tr = {
 826         .name           = "rfd",
 827         .major          = RFD_FTL_MAJOR,
 828         .part_bits      = PART_BITS,
 829         .blksize        = SECTOR_SIZE,
 830
 831         .readsect       = rfd_ftl_readsect,
 832         .writesect      = rfd_ftl_writesect,
 833         .getgeo         = rfd_ftl_getgeo,
 834         .add_mtd        = rfd_ftl_add_mtd,
 835         .remove_dev     = rfd_ftl_remove_dev,
 836         .owner          = THIS_MODULE,
 837 };
 838
 839 static int __init init_rfd_ftl(void)
 840 {
 841         return register_mtd_blktrans(&rfd_ftl_tr);
 842 }
 843
 844 static void __exit cleanup_rfd_ftl(void)
 845 {
 846         deregister_mtd_blktrans(&rfd_ftl_tr);
 847 }
 848
 849 module_init(init_rfd_ftl);
 850 module_exit(cleanup_rfd_ftl);
 851
 852 MODULE_LICENSE("GPL");
 853 MODULE_AUTHOR("Sean Young <sean@mess.org>");
 854 MODULE_DESCRIPTION("Support code for RFD Flash Translation Layer, "
 855                 "used by General Software's Embedded BIOS");
 856