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 #include <linux/module.h>
  22
  23 #include <asm/types.h>
  24
  25 static int block_size = 0;
  26 module_param(block_size, int, 0);
  27 MODULE_PARM_DESC(block_size, "Block size to use by RFD, defaults to erase unit size");
  28
  29 #define PREFIX "rfd_ftl: "
  30
  31 /* This major has been assigned by device@lanana.org */
  32 #ifndef RFD_FTL_MAJOR
  33 #define RFD_FTL_MAJOR           256
  34 #endif
  35
  36 /* Maximum number of partitions in an FTL region */
  37 #define PART_BITS               4
  38
  39 /* An erase unit should start with this value */
  40 #define RFD_MAGIC               0x9193
  41
  42 /* the second value is 0xffff or 0xffc8; function unknown */
  43
  44 /* the third value is always 0xffff, ignored */
  45
  46 /* next is an array of mapping for each corresponding sector */
  47 #define HEADER_MAP_OFFSET       3
  48 #define SECTOR_DELETED          0x0000
  49 #define SECTOR_ZERO             0xfffe
  50 #define SECTOR_FREE             0xffff
  51
  52 #define SECTOR_SIZE             512
  53
  54 #define SECTORS_PER_TRACK       63
  55
  56 struct block {
  57         enum {
  58                 BLOCK_OK,
  59                 BLOCK_ERASING,
  60                 BLOCK_ERASED,
  61                 BLOCK_UNUSED,
  62                 BLOCK_FAILED
  63         } state;
  64         int free_sectors;
  65         int used_sectors;
  66         int erases;
  67         u_long offset;
  68 };
  69
  70 struct partition {
  71         struct mtd_blktrans_dev mbd;
  72
  73         u_int block_size;               /* size of erase unit */
  74         u_int total_blocks;             /* number of erase units */
  75         u_int header_sectors_per_block; /* header sectors in erase unit */
  76         u_int data_sectors_per_block;   /* data sectors in erase unit */
  77         u_int sector_count;             /* sectors in translated disk */
  78         u_int header_size;              /* bytes in header sector */
  79         int reserved_block;             /* block next up for reclaim */
  80         int current_block;              /* block to write to */
  81         u16 *header_cache;              /* cached header */
  82
  83         int is_reclaiming;
  84         int cylinders;
  85         int errors;
  86         u_long *sector_map;
  87         struct block *blocks;
  88 };
  89
  90 static int rfd_ftl_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf);
  91
  92 static int build_block_map(struct partition *part, int block_no)
  93 {
  94         struct block *block = &part->blocks[block_no];
  95         int i;
  96
  97         block->offset = part->block_size * block_no;
  98
  99         if (le16_to_cpu(part->header_cache[0]) != RFD_MAGIC) {
 100                 block->state = BLOCK_UNUSED;
 101                 return -ENOENT;
 102         }
 103
 104         block->state = BLOCK_OK;
 105
 106         for (i=0; i<part->data_sectors_per_block; i++) {
 107                 u16 entry;
 108
 109                 entry = le16_to_cpu(part->header_cache[HEADER_MAP_OFFSET + i]);
 110
 111                 if (entry == SECTOR_DELETED)
 112                         continue;
 113
 114                 if (entry == SECTOR_FREE) {
 115                         block->free_sectors++;
 116                         continue;
 117                 }
 118
 119                 if (entry == SECTOR_ZERO)
 120                         entry = 0;
 121
 122                 if (entry >= part->sector_count) {
 123                         printk(KERN_WARNING PREFIX
 124                                 "'%s': unit #%d: entry %d corrupt, "
 125                                 "sector %d out of range\n",
 126                                 part->mbd.mtd->name, block_no, i, entry);
 127                         continue;
 128                 }
 129
 130                 if (part->sector_map[entry] != -1) {
 131                         printk(KERN_WARNING PREFIX
 132                                 "'%s': more than one entry for sector %d\n",
 133                                 part->mbd.mtd->name, entry);
 134                         part->errors = 1;
 135                         continue;
 136                 }
 137
 138                 part->sector_map[entry] = block->offset +
 139                         (i + part->header_sectors_per_block) * SECTOR_SIZE;
 140
 141                 block->used_sectors++;
 142         }
 143
 144         if (block->free_sectors == part->data_sectors_per_block)
 145                 part->reserved_block = block_no;
 146
 147         return 0;
 148 }
 149
 150 static int scan_header(struct partition *part)
 151 {
 152         int sectors_per_block;
 153         int i, rc = -ENOMEM;
 154         int blocks_found;
 155         size_t retlen;
 156
 157         sectors_per_block = part->block_size / SECTOR_SIZE;
 158         part->total_blocks = (u32)part->mbd.mtd->size / part->block_size;
 159
 160         if (part->total_blocks < 2)
 161                 return -ENOENT;
 162
 163         /* each erase block has three bytes header, followed by the map */
 164         part->header_sectors_per_block =
 165                         ((HEADER_MAP_OFFSET + sectors_per_block) *
 166                         sizeof(u16) + SECTOR_SIZE - 1) / SECTOR_SIZE;
 167
 168         part->data_sectors_per_block = sectors_per_block -
 169                         part->header_sectors_per_block;
 170
 171         part->header_size = (HEADER_MAP_OFFSET +
 172                         part->data_sectors_per_block) * sizeof(u16);
 173
 174         part->cylinders = (part->data_sectors_per_block *
 175                         (part->total_blocks - 1) - 1) / SECTORS_PER_TRACK;
 176
 177         part->sector_count = part->cylinders * SECTORS_PER_TRACK;
 178
 179         part->current_block = -1;
 180         part->reserved_block = -1;
 181         part->is_reclaiming = 0;
 182
 183         part->header_cache = kmalloc(part->header_size, GFP_KERNEL);
 184         if (!part->header_cache)
 185                 goto err;
 186
 187         part->blocks = kcalloc(part->total_blocks, sizeof(struct block),
 188                         GFP_KERNEL);
 189         if (!part->blocks)
 190                 goto err;
 191
 192         part->sector_map = vmalloc(part->sector_count * sizeof(u_long));
 193         if (!part->sector_map) {
 194                 printk(KERN_ERR PREFIX "'%s': unable to allocate memory for "
 195                         "sector map", part->mbd.mtd->name);
 196                 goto err;
 197         }
 198
 199         for (i=0; i<part->sector_count; i++)
 200                 part->sector_map[i] = -1;
 201
 202         for (i=0, blocks_found=0; i<part->total_blocks; i++) {
 203                 rc = part->mbd.mtd->read(part->mbd.mtd,
 204                                 i * part->block_size, part->header_size,
 205                                 &retlen, (u_char*)part->header_cache);
 206
 207                 if (!rc && retlen != part->header_size)
 208                         rc = -EIO;
 209
 210                 if (rc)
 211                         goto err;
 212
 213                 if (!build_block_map(part, i))
 214                         blocks_found++;
 215         }
 216
 217         if (blocks_found == 0) {
 218                 printk(KERN_NOTICE PREFIX "no RFD magic found in '%s'\n",
 219                                 part->mbd.mtd->name);
 220                 rc = -ENOENT;
 221                 goto err;
 222         }
 223
 224         if (part->reserved_block == -1) {
 225                 printk(KERN_WARNING PREFIX "'%s': no empty erase unit found\n",
 226                                 part->mbd.mtd->name);
 227
 228                 part->errors = 1;
 229         }
 230
 231         return 0;
 232
 233 err:
 234         vfree(part->sector_map);
 235         kfree(part->header_cache);
 236         kfree(part->blocks);
 237
 238         return rc;
 239 }
 240
 241 static int rfd_ftl_readsect(struct mtd_blktrans_dev *dev, u_long sector, char *buf)
 242 {
 243         struct partition *part = (struct partition*)dev;
 244         u_long addr;
 245         size_t retlen;
 246         int rc;
 247
 248         if (sector >= part->sector_count)
 249                 return -EIO;
 250
 251         addr = part->sector_map[sector];
 252         if (addr != -1) {
 253                 rc = part->mbd.mtd->read(part->mbd.mtd, addr, SECTOR_SIZE,
 254                                                 &retlen, (u_char*)buf);
 255                 if (!rc && retlen != SECTOR_SIZE)
 256                         rc = -EIO;
 257
 258                 if (rc) {
 259                         printk(KERN_WARNING PREFIX "error reading '%s' at "
 260                                 "0x%lx\n", part->mbd.mtd->name, addr);
 261                         return rc;
 262                 }
 263         } else
 264                 memset(buf, 0, SECTOR_SIZE);
 265
 266         return 0;
 267 }
 268
 269 static void erase_callback(struct erase_info *erase)
 270 {
 271         struct partition *part;
 272         u16 magic;
 273         int i, rc;
 274         size_t retlen;
 275
 276         part = (struct partition*)erase->priv;
 277
 278         i = (u32)erase->addr / part->block_size;
 279         if (i >= part->total_blocks || part->blocks[i].offset != erase->addr ||
 280             erase->addr > UINT_MAX) {
 281                 printk(KERN_ERR PREFIX "erase callback for unknown offset %llx "
 282                                 "on '%s'\n", (unsigned long long)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%llx on '%s', "
 288                                 "state %d\n", (unsigned long long)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 = 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 %llx,%llx on '%s' "
 349                                 "failed\n", (unsigned long long)erase->addr,
 350                                 (unsigned long long)erase->len, 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 = 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 || mtd->size > UINT_MAX)
 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 }
 822
 823 static struct mtd_blktrans_ops rfd_ftl_tr = {
 824         .name           = "rfd",
 825         .major          = RFD_FTL_MAJOR,
 826         .part_bits      = PART_BITS,
 827         .blksize        = SECTOR_SIZE,
 828
 829         .readsect       = rfd_ftl_readsect,
 830         .writesect      = rfd_ftl_writesect,
 831         .getgeo         = rfd_ftl_getgeo,
 832         .add_mtd        = rfd_ftl_add_mtd,
 833         .remove_dev     = rfd_ftl_remove_dev,
 834         .owner          = THIS_MODULE,
 835 };
 836
 837 static int __init init_rfd_ftl(void)
 838 {
 839         return register_mtd_blktrans(&rfd_ftl_tr);
 840 }
 841
 842 static void __exit cleanup_rfd_ftl(void)
 843 {
 844         deregister_mtd_blktrans(&rfd_ftl_tr);
 845 }
 846
 847 module_init(init_rfd_ftl);
 848 module_exit(cleanup_rfd_ftl);
 849
 850 MODULE_LICENSE("GPL");
 851 MODULE_AUTHOR("Sean Young <sean@mess.org>");
 852 MODULE_DESCRIPTION("Support code for RFD Flash Translation Layer, "
 853                 "used by General Software's Embedded BIOS");
 854