drivers/mtd/rfd_ftl.c

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