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 = 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 = erase->addr / part->block_size;
 280         if (i >= part->total_blocks || part->blocks[i].offset != erase->addr) {
 281                 printk(KERN_ERR PREFIX "erase callback for unknown offset %x "
 282                                 "on '%s'\n", erase->addr, part->mbd.mtd->name);
 283                 return;
 284         }
 285
 286         if (erase->state != MTD_ERASE_DONE) {
 287                 printk(KERN_WARNING PREFIX "erase failed at 0x%x on '%s', "
 288                                 "state %d\n", erase->addr,
 289                                 part->mbd.mtd->name, erase->state);
 290
 291                 part->blocks[i].state = BLOCK_FAILED;
 292                 part->blocks[i].free_sectors = 0;
 293                 part->blocks[i].used_sectors = 0;
 294
 295                 kfree(erase);
 296
 297                 return;
 298         }
 299
 300         magic = const_cpu_to_le16(RFD_MAGIC);
 301
 302         part->blocks[i].state = BLOCK_ERASED;
 303         part->blocks[i].free_sectors = part->data_sectors_per_block;
 304         part->blocks[i].used_sectors = 0;
 305         part->blocks[i].erases++;
 306
 307         rc = part->mbd.mtd->write(part->mbd.mtd,
 308                 part->blocks[i].offset, sizeof(magic), &retlen,
 309                 (u_char*)&magic);
 310
 311         if (!rc && retlen != sizeof(magic))
 312                 rc = -EIO;
 313
 314         if (rc) {
 315                 printk(KERN_ERR PREFIX "'%s': unable to write RFD "
 316                                 "header at 0x%lx\n",
 317                                 part->mbd.mtd->name,
 318                                 part->blocks[i].offset);
 319                 part->blocks[i].state = BLOCK_FAILED;
 320         }
 321         else
 322                 part->blocks[i].state = BLOCK_OK;
 323
 324         kfree(erase);
 325 }
 326
 327 static int erase_block(struct partition *part, int block)
 328 {
 329         struct erase_info *erase;
 330         int rc = -ENOMEM;
 331
 332         erase = kmalloc(sizeof(struct erase_info), GFP_KERNEL);
 333         if (!erase)
 334                 goto err;
 335
 336         erase->mtd = part->mbd.mtd;
 337         erase->callback = erase_callback;
 338         erase->addr = part->blocks[block].offset;
 339         erase->len = part->block_size;
 340         erase->priv = (u_long)part;
 341
 342         part->blocks[block].state = BLOCK_ERASING;
 343         part->blocks[block].free_sectors = 0;
 344
 345         rc = part->mbd.mtd->erase(part->mbd.mtd, erase);
 346
 347         if (rc) {
 348                 printk(KERN_ERR PREFIX "erase of region %x,%x on '%s' "
 349                                 "failed\n", erase->addr, erase->len,
 350                                 part->mbd.mtd->name);
 351                 kfree(erase);
 352         }
 353
 354 err:
 355         return rc;
 356 }
 357
 358 static int move_block_contents(struct partition *part, int block_no, u_long *old_sector)
 359 {
 360         void *sector_data;
 361         u16 *map;
 362         size_t retlen;
 363         int i, rc = -ENOMEM;
 364
 365         part->is_reclaiming = 1;
 366
 367         sector_data = kmalloc(SECTOR_SIZE, GFP_KERNEL);
 368         if (!sector_data)
 369                 goto err3;
 370
 371         map = kmalloc(part->header_size, GFP_KERNEL);
 372         if (!map)
 373                 goto err2;
 374
 375         rc = part->mbd.mtd->read(part->mbd.mtd,
 376                 part->blocks[block_no].offset, part->header_size,
 377                 &retlen, (u_char*)map);
 378
 379         if (!rc && retlen != part->header_size)
 380                 rc = -EIO;
 381
 382         if (rc) {
 383                 printk(KERN_ERR PREFIX "error reading '%s' at "
 384                         "0x%lx\n", part->mbd.mtd->name,
 385                         part->blocks[block_no].offset);
 386
 387                 goto err;
 388         }
 389
 390         for (i=0; i<part->data_sectors_per_block; i++) {
 391                 u16 entry = le16_to_cpu(map[HEADER_MAP_OFFSET + i]);
 392                 u_long addr;
 393
 394
 395                 if (entry == SECTOR_FREE || entry == SECTOR_DELETED)
 396                         continue;
 397
 398                 if (entry == SECTOR_ZERO)
 399                         entry = 0;
 400
 401                 /* already warned about and ignored in build_block_map() */
 402                 if (entry >= part->sector_count)
 403                         continue;
 404
 405                 addr = part->blocks[block_no].offset +
 406                         (i + part->header_sectors_per_block) * SECTOR_SIZE;
 407
 408                 if (*old_sector == addr) {
 409                         *old_sector = -1;
 410                         if (!part->blocks[block_no].used_sectors--) {
 411                                 rc = erase_block(part, block_no);
 412                                 break;
 413                         }
 414                         continue;
 415                 }
 416                 rc = part->mbd.mtd->read(part->mbd.mtd, addr,
 417                         SECTOR_SIZE, &retlen, sector_data);
 418
 419                 if (!rc && retlen != SECTOR_SIZE)
 420                         rc = -EIO;
 421
 422                 if (rc) {
 423                         printk(KERN_ERR PREFIX "'%s': Unable to "
 424                                 "read sector for relocation\n",
 425                                 part->mbd.mtd->name);
 426
 427                         goto err;
 428                 }
 429
 430                 rc = rfd_ftl_writesect((struct mtd_blktrans_dev*)part,
 431                                 entry, sector_data);
 432
 433                 if (rc)
 434                         goto err;
 435         }
 436
 437 err:
 438         kfree(map);
 439 err2:
 440         kfree(sector_data);
 441 err3:
 442         part->is_reclaiming = 0;
 443
 444         return rc;
 445 }
 446
 447 static int reclaim_block(struct partition *part, u_long *old_sector)
 448 {
 449         int block, best_block, score, old_sector_block;
 450         int rc;
 451
 452         /* we have a race if sync doesn't exist */
 453         if (part->mbd.mtd->sync)
 454                 part->mbd.mtd->sync(part->mbd.mtd);
 455
 456         score = 0x7fffffff; /* MAX_INT */
 457         best_block = -1;
 458         if (*old_sector != -1)
 459                 old_sector_block = *old_sector / part->block_size;
 460         else
 461                 old_sector_block = -1;
 462
 463         for (block=0; block<part->total_blocks; block++) {
 464                 int this_score;
 465
 466                 if (block == part->reserved_block)
 467                         continue;
 468
 469                 /*
 470                  * Postpone reclaiming if there is a free sector as
 471                  * more removed sectors is more efficient (have to move
 472                  * less).
 473                  */
 474                 if (part->blocks[block].free_sectors)
 475                         return 0;
 476
 477                 this_score = part->blocks[block].used_sectors;
 478
 479                 if (block == old_sector_block)
 480                         this_score--;
 481                 else {
 482                         /* no point in moving a full block */
 483                         if (part->blocks[block].used_sectors ==
 484                                         part->data_sectors_per_block)
 485                                 continue;
 486                 }
 487
 488                 this_score += part->blocks[block].erases;
 489
 490                 if (this_score < score) {
 491                         best_block = block;
 492                         score = this_score;
 493                 }
 494         }
 495
 496         if (best_block == -1)
 497                 return -ENOSPC;
 498
 499         part->current_block = -1;
 500         part->reserved_block = best_block;
 501
 502         pr_debug("reclaim_block: reclaiming block #%d with %d used "
 503                  "%d free sectors\n", best_block,
 504                  part->blocks[best_block].used_sectors,
 505                  part->blocks[best_block].free_sectors);
 506
 507         if (part->blocks[best_block].used_sectors)
 508                 rc = move_block_contents(part, best_block, old_sector);
 509         else
 510                 rc = erase_block(part, best_block);
 511
 512         return rc;
 513 }
 514
 515 /*
 516  * IMPROVE: It would be best to choose the block with the most deleted sectors,
 517  * because if we fill that one up first it'll have the most chance of having
 518  * the least live sectors at reclaim.
 519  */
 520 static int find_free_block(struct partition *part)
 521 {
 522         int block, stop;
 523
 524         block = part->current_block == -1 ?
 525                         jiffies % part->total_blocks : part->current_block;
 526         stop = block;
 527
 528         do {
 529                 if (part->blocks[block].free_sectors &&
 530                                 block != part->reserved_block)
 531                         return block;
 532
 533                 if (part->blocks[block].state == BLOCK_UNUSED)
 534                         erase_block(part, 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_writable_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_ERR 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_ERR 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_writable_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_ERR 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_ERR 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 = kzalloc(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_WARNING PREFIX "please provide block_size");
 780                         goto out;
 781                 } else
 782                         part->block_size = mtd->erasesize;
 783         }
 784
 785         if (scan_header(part) == 0) {
 786                 part->mbd.size = part->sector_count;
 787                 part->mbd.tr = tr;
 788                 part->mbd.devnum = -1;
 789                 if (!(mtd->flags & MTD_WRITEABLE))
 790                         part->mbd.readonly = 1;
 791                 else if (part->errors) {
 792                         printk(KERN_WARNING PREFIX "'%s': errors found, "
 793                                         "setting read-only\n", mtd->name);
 794                         part->mbd.readonly = 1;
 795                 }
 796
 797                 printk(KERN_INFO PREFIX "name: '%s' type: %d flags %x\n",
 798                                 mtd->name, mtd->type, mtd->flags);
 799
 800                 if (!add_mtd_blktrans_dev((void*)part))
 801                         return;
 802         }
 803 out:
 804         kfree(part);
 805 }
 806
 807 static void rfd_ftl_remove_dev(struct mtd_blktrans_dev *dev)
 808 {
 809         struct partition *part = (struct partition*)dev;
 810         int i;
 811
 812         for (i=0; i<part->total_blocks; i++) {
 813                 pr_debug("rfd_ftl_remove_dev:'%s': erase unit #%02d: %d erases\n",
 814                         part->mbd.mtd->name, i, part->blocks[i].erases);
 815         }
 816
 817         del_mtd_blktrans_dev(dev);
 818         vfree(part->sector_map);
 819         kfree(part->header_cache);
 820         kfree(part->blocks);
 821         kfree(part);
 822 }
 823
 824 static struct mtd_blktrans_ops rfd_ftl_tr = {
 825         .name           = "rfd",
 826         .major          = RFD_FTL_MAJOR,
 827         .part_bits      = PART_BITS,
 828         .blksize        = SECTOR_SIZE,
 829
 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