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  * $Id: rfd_ftl.c,v 1.5 2005/11/07 11:14:21 gleixner Exp $
   7  *
   8  * This type of flash translation layer (FTL) is used by the Embedded BIOS
   9  * by General Software. It is known as the Resident Flash Disk (RFD), see:
  10  *
  11  *      http://www.gensw.com/pages/prod/bios/rfd.htm
  12  *
  13  * based on ftl.c
  14  */
  15
  16 #include <linux/hdreg.h>
  17 #include <linux/init.h>
  18 #include <linux/mtd/blktrans.h>
  19 #include <linux/mtd/mtd.h>
  20 #include <linux/vmalloc.h>
  21 #include <linux/slab.h>
  22 #include <linux/jiffies.h>
  23
  24 #include <asm/types.h>
  25
  26 #define const_cpu_to_le16       __constant_cpu_to_le16
  27
  28 static int block_size = 0;
  29 module_param(block_size, int, 0);
  30 MODULE_PARM_DESC(block_size, "Block size to use by RFD, defaults to erase unit size");
  31
  32 #define PREFIX "rfd_ftl: "
  33
  34 /* This major has been assigned by device@lanana.org */
  35 #ifndef RFD_FTL_MAJOR
  36 #define RFD_FTL_MAJOR           256
  37 #endif
  38
  39 /* Maximum number of partitions in an FTL region */
  40 #define PART_BITS               4
  41
  42 /* An erase unit should start with this value */
  43 #define RFD_MAGIC               0x9193
  44
  45 /* the second value is 0xffff or 0xffc8; function unknown */
  46
  47 /* the third value is always 0xffff, ignored */
  48
  49 /* next is an array of mapping for each corresponding sector */
  50 #define HEADER_MAP_OFFSET       3
  51 #define SECTOR_DELETED          0x0000
  52 #define SECTOR_ZERO             0xfffe
  53 #define SECTOR_FREE             0xffff
  54
  55 #define SECTOR_SIZE             512
  56
  57 #define SECTORS_PER_TRACK       63
  58
  59 struct block {
  60         enum {
  61                 BLOCK_OK,
  62                 BLOCK_ERASING,
  63                 BLOCK_ERASED,
  64                 BLOCK_FAILED
  65         } state;
  66         int free_sectors;
  67         int used_sectors;
  68         int erases;
  69         u_long offset;
  70 };
  71
  72 struct partition {
  73         struct mtd_blktrans_dev mbd;
  74
  75         u_int block_size;               /* size of erase unit */
  76         u_int total_blocks;             /* number of erase units */
  77         u_int header_sectors_per_block; /* header sectors in erase unit */
  78         u_int data_sectors_per_block;   /* data sectors in erase unit */
  79         u_int sector_count;             /* sectors in translated disk */
  80         u_int header_size;              /* bytes in header sector */
  81         int reserved_block;             /* block next up for reclaim */
  82         int current_block;              /* block to write to */
  83         u16 *header_cache;              /* cached header */
  84
  85         int is_reclaiming;
  86         int cylinders;
  87         int errors;
  88         u_long *sector_map;
  89         struct block *blocks;
  90 };
  91
  92 static int rfd_ftl_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf);
  93
  94 static int build_block_map(struct partition *part, int block_no)
  95 {
  96         struct block *block = &part->blocks[block_no];
  97         int i;
  98
  99         block->offset = part->block_size * block_no;
 100
 101         if (le16_to_cpu(part->header_cache[0]) != RFD_MAGIC) {
 102                 block->state = BLOCK_ERASED; /* assumption */
 103                 block->free_sectors = part->data_sectors_per_block;
 104                 part->reserved_block = block_no;
 105                 return 1;
 106         }
 107
 108         block->state = BLOCK_OK;
 109
 110         for (i=0; i<part->data_sectors_per_block; i++) {
 111                 u16 entry;
 112
 113                 entry = le16_to_cpu(part->header_cache[HEADER_MAP_OFFSET + i]);
 114
 115                 if (entry == SECTOR_DELETED)
 116                         continue;
 117
 118                 if (entry == SECTOR_FREE) {
 119                         block->free_sectors++;
 120                         continue;
 121                 }
 122
 123                 if (entry == SECTOR_ZERO)
 124                         entry = 0;
 125
 126                 if (entry >= part->sector_count) {
 127                         printk(KERN_NOTICE PREFIX
 128                                 "'%s': unit #%d: entry %d corrupt, "
 129                                 "sector %d out of range\n",
 130                                 part->mbd.mtd->name, block_no, i, entry);
 131                         continue;
 132                 }
 133
 134                 if (part->sector_map[entry] != -1) {
 135                         printk(KERN_NOTICE PREFIX
 136                                 "'%s': more than one entry for sector %d\n",
 137                                 part->mbd.mtd->name, entry);
 138                         part->errors = 1;
 139                         continue;
 140                 }
 141
 142                 part->sector_map[entry] = block->offset +
 143                         (i + part->header_sectors_per_block) * SECTOR_SIZE;
 144
 145                 block->used_sectors++;
 146         }
 147
 148         if (block->free_sectors == part->data_sectors_per_block)
 149                 part->reserved_block = block_no;
 150
 151         return 0;
 152 }
 153
 154 static int scan_header(struct partition *part)
 155 {
 156         int sectors_per_block;
 157         int i, rc = -ENOMEM;
 158         int blocks_found;
 159         size_t retlen;
 160
 161         sectors_per_block = part->block_size / SECTOR_SIZE;
 162         part->total_blocks = part->mbd.mtd->size / part->block_size;
 163
 164         if (part->total_blocks < 2)
 165                 return -ENOENT;
 166
 167         /* each erase block has three bytes header, followed by the map */
 168         part->header_sectors_per_block =
 169                         ((HEADER_MAP_OFFSET + sectors_per_block) *
 170                         sizeof(u16) + SECTOR_SIZE - 1) / SECTOR_SIZE;
 171
 172         part->data_sectors_per_block = sectors_per_block -
 173                         part->header_sectors_per_block;
 174
 175         part->header_size = (HEADER_MAP_OFFSET +
 176                         part->data_sectors_per_block) * sizeof(u16);
 177
 178         part->cylinders = (part->data_sectors_per_block *
 179                         (part->total_blocks - 1) - 1) / SECTORS_PER_TRACK;
 180
 181         part->sector_count = part->cylinders * SECTORS_PER_TRACK;
 182
 183         part->current_block = -1;
 184         part->reserved_block = -1;
 185         part->is_reclaiming = 0;
 186
 187         part->header_cache = kmalloc(part->header_size, GFP_KERNEL);
 188         if (!part->header_cache)
 189                 goto err;
 190
 191         part->blocks = kcalloc(part->total_blocks, sizeof(struct block),
 192                         GFP_KERNEL);
 193         if (!part->blocks)
 194                 goto err;
 195
 196         part->sector_map = vmalloc(part->sector_count * sizeof(u_long));
 197         if (!part->sector_map) {
 198                 printk(KERN_ERR PREFIX "'%s': unable to allocate memory for "
 199                         "sector map", part->mbd.mtd->name);
 200                 goto err;
 201         }
 202
 203         for (i=0; i<part->sector_count; i++)
 204                 part->sector_map[i] = -1;
 205
 206         for (i=0, blocks_found=0; i<part->total_blocks; i++) {
 207                 rc = part->mbd.mtd->read(part->mbd.mtd,
 208                                 i * part->block_size, part->header_size,
 209                                 &retlen, (u_char*)part->header_cache);
 210
 211                 if (!rc && retlen != part->header_size)
 212                         rc = -EIO;
 213
 214                 if (rc)
 215                         goto err;
 216
 217                 if (!build_block_map(part, i))
 218                         blocks_found++;
 219         }
 220
 221         if (blocks_found == 0) {
 222                 printk(KERN_NOTICE PREFIX "no RFD magic found in '%s'\n",
 223                                 part->mbd.mtd->name);
 224                 rc = -ENOENT;
 225                 goto err;
 226         }
 227
 228         if (part->reserved_block == -1) {
 229                 printk(KERN_NOTICE PREFIX "'%s': no empty erase unit found\n",
 230                                 part->mbd.mtd->name);
 231
 232                 part->errors = 1;
 233         }
 234
 235         return 0;
 236
 237 err:
 238         vfree(part->sector_map);
 239         kfree(part->header_cache);
 240         kfree(part->blocks);
 241
 242         return rc;
 243 }
 244
 245 static int rfd_ftl_readsect(struct mtd_blktrans_dev *dev, u_long sector, char *buf)
 246 {
 247         struct partition *part = (struct partition*)dev;
 248         u_long addr;
 249         size_t retlen;
 250         int rc;
 251
 252         if (sector >= part->sector_count)
 253                 return -EIO;
 254
 255         addr = part->sector_map[sector];
 256         if (addr != -1) {
 257                 rc = part->mbd.mtd->read(part->mbd.mtd, addr, SECTOR_SIZE,
 258                                                 &retlen, (u_char*)buf);
 259                 if (!rc && retlen != SECTOR_SIZE)
 260                         rc = -EIO;
 261
 262                 if (rc) {
 263                         printk(KERN_WARNING PREFIX "error reading '%s' at "
 264                                 "0x%lx\n", part->mbd.mtd->name, addr);
 265                         return rc;
 266                 }
 267         } else
 268                 memset(buf, 0, SECTOR_SIZE);
 269
 270         return 0;
 271 }
 272
 273 static void erase_callback(struct erase_info *erase)
 274 {
 275         struct partition *part;
 276         u16 magic;
 277         int i, rc;
 278         size_t retlen;
 279
 280         part = (struct partition*)erase->priv;
 281
 282         i = erase->addr / part->block_size;
 283         if (i >= part->total_blocks || part->blocks[i].offset != erase->addr) {
 284                 printk(KERN_ERR PREFIX "erase callback for unknown offset %x "
 285                                 "on '%s'\n", erase->addr, part->mbd.mtd->name);
 286                 return;
 287         }
 288
 289         if (erase->state != MTD_ERASE_DONE) {
 290                 printk(KERN_WARNING PREFIX "erase failed at 0x%x on '%s', "
 291                                 "state %d\n", erase->addr,
 292                                 part->mbd.mtd->name, erase->state);
 293
 294                 part->blocks[i].state = BLOCK_FAILED;
 295                 part->blocks[i].free_sectors = 0;
 296                 part->blocks[i].used_sectors = 0;
 297
 298                 kfree(erase);
 299
 300                 return;
 301         }
 302
 303         magic = const_cpu_to_le16(RFD_MAGIC);
 304
 305         part->blocks[i].state = BLOCK_ERASED;
 306         part->blocks[i].free_sectors = part->data_sectors_per_block;
 307         part->blocks[i].used_sectors = 0;
 308         part->blocks[i].erases++;
 309
 310         rc = part->mbd.mtd->write(part->mbd.mtd,
 311                 part->blocks[i].offset, sizeof(magic), &retlen,
 312                 (u_char*)&magic);
 313
 314         if (!rc && retlen != sizeof(magic))
 315                 rc = -EIO;
 316
 317         if (rc) {
 318                 printk(KERN_NOTICE PREFIX "'%s': unable to write RFD "
 319                                 "header at 0x%lx\n",
 320                                 part->mbd.mtd->name,
 321                                 part->blocks[i].offset);
 322                 part->blocks[i].state = BLOCK_FAILED;
 323         }
 324         else
 325                 part->blocks[i].state = BLOCK_OK;
 326
 327         kfree(erase);
 328 }
 329
 330 static int erase_block(struct partition *part, int block)
 331 {
 332         struct erase_info *erase;
 333         int rc = -ENOMEM;
 334
 335         erase = kmalloc(sizeof(struct erase_info), GFP_KERNEL);
 336         if (!erase)
 337                 goto err;
 338
 339         erase->mtd = part->mbd.mtd;
 340         erase->callback = erase_callback;
 341         erase->addr = part->blocks[block].offset;
 342         erase->len = part->block_size;
 343         erase->priv = (u_long)part;
 344
 345         part->blocks[block].state = BLOCK_ERASING;
 346         part->blocks[block].free_sectors = 0;
 347
 348         rc = part->mbd.mtd->erase(part->mbd.mtd, erase);
 349
 350         if (rc) {
 351                 printk(KERN_WARNING PREFIX "erase of region %x,%x on '%s' "
 352                                 "failed\n", erase->addr, erase->len,
 353                                 part->mbd.mtd->name);
 354                 kfree(erase);
 355         }
 356
 357 err:
 358         return rc;
 359 }
 360
 361 static int move_block_contents(struct partition *part, int block_no, u_long *old_sector)
 362 {
 363         void *sector_data;
 364         u16 *map;
 365         size_t retlen;
 366         int i, rc = -ENOMEM;
 367
 368         part->is_reclaiming = 1;
 369
 370         sector_data = kmalloc(SECTOR_SIZE, GFP_KERNEL);
 371         if (!sector_data)
 372                 goto err3;
 373
 374         map = kmalloc(part->header_size, GFP_KERNEL);
 375         if (!map)
 376                 goto err2;
 377
 378         rc = part->mbd.mtd->read(part->mbd.mtd,
 379                 part->blocks[block_no].offset, part->header_size,
 380                 &retlen, (u_char*)map);
 381
 382         if (!rc && retlen != part->header_size)
 383                 rc = -EIO;
 384
 385         if (rc) {
 386                 printk(KERN_NOTICE PREFIX "error reading '%s' at "
 387                         "0x%lx\n", part->mbd.mtd->name,
 388                         part->blocks[block_no].offset);
 389
 390                 goto err;
 391         }
 392
 393         for (i=0; i<part->data_sectors_per_block; i++) {
 394                 u16 entry = le16_to_cpu(map[HEADER_MAP_OFFSET + i]);
 395                 u_long addr;
 396
 397
 398                 if (entry == SECTOR_FREE || entry == SECTOR_DELETED)
 399                         continue;
 400
 401                 if (entry == SECTOR_ZERO)
 402                         entry = 0;
 403
 404                 /* already warned about and ignored in build_block_map() */
 405                 if (entry >= part->sector_count)
 406                         continue;
 407
 408                 addr = part->blocks[block_no].offset +
 409                         (i + part->header_sectors_per_block) * SECTOR_SIZE;
 410
 411                 if (*old_sector == addr) {
 412                         *old_sector = -1;
 413                         if (!part->blocks[block_no].used_sectors--) {
 414                                 rc = erase_block(part, block_no);
 415                                 break;
 416                         }
 417                         continue;
 418                 }
 419                 rc = part->mbd.mtd->read(part->mbd.mtd, addr,
 420                         SECTOR_SIZE, &retlen, sector_data);
 421
 422                 if (!rc && retlen != SECTOR_SIZE)
 423                         rc = -EIO;
 424
 425                 if (rc) {
 426                         printk(KERN_NOTICE PREFIX "'%s': Unable to "
 427                                 "read sector for relocation\n",
 428                                 part->mbd.mtd->name);
 429
 430                         goto err;
 431                 }
 432
 433                 rc = rfd_ftl_writesect((struct mtd_blktrans_dev*)part,
 434                                 entry, sector_data);
 435
 436                 if (rc)
 437                         goto err;
 438         }
 439
 440 err:
 441         kfree(map);
 442 err2:
 443         kfree(sector_data);
 444 err3:
 445         part->is_reclaiming = 0;
 446
 447         return rc;
 448 }
 449
 450 static int reclaim_block(struct partition *part, u_long *old_sector)
 451 {
 452         int block, best_block, score, old_sector_block;
 453         int rc;
 454
 455         /* we have a race if sync doesn't exist */
 456         if (part->mbd.mtd->sync)
 457                 part->mbd.mtd->sync(part->mbd.mtd);
 458
 459         score = 0x7fffffff; /* MAX_INT */
 460         best_block = -1;
 461         if (*old_sector != -1)
 462                 old_sector_block = *old_sector / part->block_size;
 463         else
 464                 old_sector_block = -1;
 465
 466         for (block=0; block<part->total_blocks; block++) {
 467                 int this_score;
 468
 469                 if (block == part->reserved_block)
 470                         continue;
 471
 472                 /*
 473                  * Postpone reclaiming if there is a free sector as
 474                  * more removed sectors is more efficient (have to move
 475                  * less).
 476                  */
 477                 if (part->blocks[block].free_sectors)
 478                         return 0;
 479
 480                 this_score = part->blocks[block].used_sectors;
 481
 482                 if (block == old_sector_block)
 483                         this_score--;
 484                 else {
 485                         /* no point in moving a full block */
 486                         if (part->blocks[block].used_sectors ==
 487                                         part->data_sectors_per_block)
 488                                 continue;
 489                 }
 490
 491                 this_score += part->blocks[block].erases;
 492
 493                 if (this_score < score) {
 494                         best_block = block;
 495                         score = this_score;
 496                 }
 497         }
 498
 499         if (best_block == -1)
 500                 return -ENOSPC;
 501
 502         part->current_block = -1;
 503         part->reserved_block = best_block;
 504
 505         pr_debug("reclaim_block: reclaiming block #%d with %d used "
 506                  "%d free sectors\n", best_block,
 507                  part->blocks[best_block].used_sectors,
 508                  part->blocks[best_block].free_sectors);
 509
 510         if (part->blocks[best_block].used_sectors)
 511                 rc = move_block_contents(part, best_block, old_sector);
 512         else
 513                 rc = erase_block(part, best_block);
 514
 515         return rc;
 516 }
 517
 518 /*
 519  * IMPROVE: It would be best to choose the block with the most deleted sectors,
 520  * because if we fill that one up first it'll have the most chance of having
 521  * the least live sectors at reclaim.
 522  */
 523 static int find_free_block(const struct partition *part)
 524 {
 525         int block, stop;
 526
 527         block = part->current_block == -1 ?
 528                         jiffies % part->total_blocks : part->current_block;
 529         stop = block;
 530
 531         do {
 532                 if (part->blocks[block].free_sectors &&
 533                                 block != part->reserved_block)
 534                         return block;
 535
 536                 if (++block >= part->total_blocks)
 537                         block = 0;
 538
 539         } while (block != stop);
 540
 541         return -1;
 542 }
 543
 544 static int find_writeable_block(struct partition *part, u_long *old_sector)
 545 {
 546         int rc, block;
 547         size_t retlen;
 548
 549         block = find_free_block(part);
 550
 551         if (block == -1) {
 552                 if (!part->is_reclaiming) {
 553                         rc = reclaim_block(part, old_sector);
 554                         if (rc)
 555                                 goto err;
 556
 557                         block = find_free_block(part);
 558                 }
 559
 560                 if (block == -1) {
 561                         rc = -ENOSPC;
 562                         goto err;
 563                 }
 564         }
 565
 566         rc = part->mbd.mtd->read(part->mbd.mtd, part->blocks[block].offset,
 567                 part->header_size, &retlen, (u_char*)part->header_cache);
 568
 569         if (!rc && retlen != part->header_size)
 570                 rc = -EIO;
 571
 572         if (rc) {
 573                 printk(KERN_NOTICE PREFIX "'%s': unable to read header at "
 574                                 "0x%lx\n", part->mbd.mtd->name,
 575                                 part->blocks[block].offset);
 576                 goto err;
 577         }
 578
 579         part->current_block = block;
 580
 581 err:
 582         return rc;
 583 }
 584
 585 static int mark_sector_deleted(struct partition *part, u_long old_addr)
 586 {
 587         int block, offset, rc;
 588         u_long addr;
 589         size_t retlen;
 590         u16 del = const_cpu_to_le16(SECTOR_DELETED);
 591
 592         block = old_addr / part->block_size;
 593         offset = (old_addr % part->block_size) / SECTOR_SIZE -
 594                 part->header_sectors_per_block;
 595
 596         addr = part->blocks[block].offset +
 597                         (HEADER_MAP_OFFSET + offset) * sizeof(u16);
 598         rc = part->mbd.mtd->write(part->mbd.mtd, addr,
 599                 sizeof(del), &retlen, (u_char*)&del);
 600
 601         if (!rc && retlen != sizeof(del))
 602                 rc = -EIO;
 603
 604         if (rc) {
 605                 printk(KERN_WARNING PREFIX "error writing '%s' at "
 606                         "0x%lx\n", part->mbd.mtd->name, addr);
 607                 if (rc)
 608                         goto err;
 609         }
 610         if (block == part->current_block)
 611                 part->header_cache[offset + HEADER_MAP_OFFSET] = del;
 612
 613         part->blocks[block].used_sectors--;
 614
 615         if (!part->blocks[block].used_sectors &&
 616             !part->blocks[block].free_sectors)
 617                 rc = erase_block(part, block);
 618
 619 err:
 620         return rc;
 621 }
 622
 623 static int find_free_sector(const struct partition *part, const struct block *block)
 624 {
 625         int i, stop;
 626
 627         i = stop = part->data_sectors_per_block - block->free_sectors;
 628
 629         do {
 630                 if (le16_to_cpu(part->header_cache[HEADER_MAP_OFFSET + i])
 631                                 == SECTOR_FREE)
 632                         return i;
 633
 634                 if (++i == part->data_sectors_per_block)
 635                         i = 0;
 636         }
 637         while(i != stop);
 638
 639         return -1;
 640 }
 641
 642 static int do_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf, ulong *old_addr)
 643 {
 644         struct partition *part = (struct partition*)dev;
 645         struct block *block;
 646         u_long addr;
 647         int i;
 648         int rc;
 649         size_t retlen;
 650         u16 entry;
 651
 652         if (part->current_block == -1 ||
 653                 !part->blocks[part->current_block].free_sectors) {
 654
 655                 rc = find_writeable_block(part, old_addr);
 656                 if (rc)
 657                         goto err;
 658         }
 659
 660         block = &part->blocks[part->current_block];
 661
 662         i = find_free_sector(part, block);
 663
 664         if (i < 0) {
 665                 rc = -ENOSPC;
 666                 goto err;
 667         }
 668
 669         addr = (i + part->header_sectors_per_block) * SECTOR_SIZE +
 670                 block->offset;
 671         rc = part->mbd.mtd->write(part->mbd.mtd,
 672                 addr, SECTOR_SIZE, &retlen, (u_char*)buf);
 673
 674         if (!rc && retlen != SECTOR_SIZE)
 675                 rc = -EIO;
 676
 677         if (rc) {
 678                 printk(KERN_WARNING PREFIX "error writing '%s' at 0x%lx\n",
 679                                 part->mbd.mtd->name, addr);
 680                 if (rc)
 681                         goto err;
 682         }
 683
 684         part->sector_map[sector] = addr;
 685
 686         entry = cpu_to_le16(sector == 0 ? SECTOR_ZERO : sector);
 687
 688         part->header_cache[i + HEADER_MAP_OFFSET] = entry;
 689
 690         addr = block->offset + (HEADER_MAP_OFFSET + i) * sizeof(u16);
 691         rc = part->mbd.mtd->write(part->mbd.mtd, addr,
 692                         sizeof(entry), &retlen, (u_char*)&entry);
 693
 694         if (!rc && retlen != sizeof(entry))
 695                 rc = -EIO;
 696
 697         if (rc) {
 698                 printk(KERN_WARNING PREFIX "error writing '%s' at 0x%lx\n",
 699                                 part->mbd.mtd->name, addr);
 700                 if (rc)
 701                         goto err;
 702         }
 703         block->used_sectors++;
 704         block->free_sectors--;
 705
 706 err:
 707         return rc;
 708 }
 709
 710 static int rfd_ftl_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf)
 711 {
 712         struct partition *part = (struct partition*)dev;
 713         u_long old_addr;
 714         int i;
 715         int rc = 0;
 716
 717         pr_debug("rfd_ftl_writesect(sector=0x%lx)\n", sector);
 718
 719         if (part->reserved_block == -1) {
 720                 rc = -EACCES;
 721                 goto err;
 722         }
 723
 724         if (sector >= part->sector_count) {
 725                 rc = -EIO;
 726                 goto err;
 727         }
 728
 729         old_addr = part->sector_map[sector];
 730
 731         for (i=0; i<SECTOR_SIZE; i++) {
 732                 if (!buf[i])
 733                         continue;
 734
 735                 rc = do_writesect(dev, sector, buf, &old_addr);
 736                 if (rc)
 737                         goto err;
 738                 break;
 739         }
 740
 741         if (i == SECTOR_SIZE)
 742                 part->sector_map[sector] = -1;
 743
 744         if (old_addr != -1)
 745                 rc = mark_sector_deleted(part, old_addr);
 746
 747 err:
 748         return rc;
 749 }
 750
 751 static int rfd_ftl_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
 752 {
 753         struct partition *part = (struct partition*)dev;
 754
 755         geo->heads = 1;
 756         geo->sectors = SECTORS_PER_TRACK;
 757         geo->cylinders = part->cylinders;
 758
 759         return 0;
 760 }
 761
 762 static void rfd_ftl_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
 763 {
 764         struct partition *part;
 765
 766         if (mtd->type != MTD_NORFLASH)
 767                 return;
 768
 769         part = kcalloc(1, sizeof(struct partition), GFP_KERNEL);
 770         if (!part)
 771                 return;
 772
 773         part->mbd.mtd = mtd;
 774
 775         if (block_size)
 776                 part->block_size = block_size;
 777         else {
 778                 if (!mtd->erasesize) {
 779                         printk(KERN_NOTICE PREFIX "please provide block_size");
 780                         return;
 781                 }
 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.blksize = SECTOR_SIZE;
 789                 part->mbd.tr = tr;
 790                 part->mbd.devnum = -1;
 791                 if (!(mtd->flags & MTD_WRITEABLE))
 792                         part->mbd.readonly = 1;
 793                 else if (part->errors) {
 794                         printk(KERN_NOTICE PREFIX "'%s': errors found, "
 795                                         "setting read-only", mtd->name);
 796                         part->mbd.readonly = 1;
 797                 }
 798
 799                 printk(KERN_INFO PREFIX "name: '%s' type: %d flags %x\n",
 800                                 mtd->name, mtd->type, mtd->flags);
 801
 802                 if (!add_mtd_blktrans_dev((void*)part))
 803                         return;
 804         }
 805
 806         kfree(part);
 807 }
 808
 809 static void rfd_ftl_remove_dev(struct mtd_blktrans_dev *dev)
 810 {
 811         struct partition *part = (struct partition*)dev;
 812         int i;
 813
 814         for (i=0; i<part->total_blocks; i++) {
 815                 pr_debug("rfd_ftl_remove_dev:'%s': erase unit #%02d: %d erases\n",
 816                         part->mbd.mtd->name, i, part->blocks[i].erases);
 817         }
 818
 819         del_mtd_blktrans_dev(dev);
 820         vfree(part->sector_map);
 821         kfree(part->header_cache);
 822         kfree(part->blocks);
 823         kfree(part);
 824 }
 825
 826 struct mtd_blktrans_ops rfd_ftl_tr = {
 827         .name           = "rfd",
 828         .major          = RFD_FTL_MAJOR,
 829         .part_bits      = PART_BITS,
 830         .readsect       = rfd_ftl_readsect,
 831         .writesect      = rfd_ftl_writesect,
 832         .getgeo         = rfd_ftl_getgeo,
 833         .add_mtd        = rfd_ftl_add_mtd,
 834         .remove_dev     = rfd_ftl_remove_dev,
 835         .owner          = THIS_MODULE,
 836 };
 837
 838 static int __init init_rfd_ftl(void)
 839 {
 840         return register_mtd_blktrans(&rfd_ftl_tr);
 841 }
 842
 843 static void __exit cleanup_rfd_ftl(void)
 844 {
 845         deregister_mtd_blktrans(&rfd_ftl_tr);
 846 }
 847
 848 module_init(init_rfd_ftl);
 849 module_exit(cleanup_rfd_ftl);
 850
 851 MODULE_LICENSE("GPL");
 852 MODULE_AUTHOR("Sean Young <sean@mess.org>");
 853 MODULE_DESCRIPTION("Support code for RFD Flash Translation Layer, "
 854                 "used by General Software's Embedded BIOS");
 855