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 1.8 2006/01/15 12:51:44 sean 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_UNUSED,
  65                 BLOCK_FAILED
  66         } state;
  67         int free_sectors;
  68         int used_sectors;
  69         int erases;
  70         u_long offset;
  71 };
  72
  73 struct partition {
  74         struct mtd_blktrans_dev mbd;
  75
  76         u_int block_size;               /* size of erase unit */
  77         u_int total_blocks;             /* number of erase units */
  78         u_int header_sectors_per_block; /* header sectors in erase unit */
  79         u_int data_sectors_per_block;   /* data sectors in erase unit */
  80         u_int sector_count;             /* sectors in translated disk */
  81         u_int header_size;              /* bytes in header sector */
  82         int reserved_block;             /* block next up for reclaim */
  83         int current_block;              /* block to write to */
  84         u16 *header_cache;              /* cached header */
  85
  86         int is_reclaiming;
  87         int cylinders;
  88         int errors;
  89         u_long *sector_map;
  90         struct block *blocks;
  91 };
  92
  93 static int rfd_ftl_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf);
  94
  95 static int build_block_map(struct partition *part, int block_no)
  96 {
  97         struct block *block = &part->blocks[block_no];
  98         int i;
  99
 100         block->offset = part->block_size * block_no;
 101
 102         if (le16_to_cpu(part->header_cache[0]) != RFD_MAGIC) {
 103                 block->state = BLOCK_UNUSED;
 104                 return -ENOENT;
 105         }
 106
 107         block->state = BLOCK_OK;
 108
 109         for (i=0; i<part->data_sectors_per_block; i++) {
 110                 u16 entry;
 111
 112                 entry = le16_to_cpu(part->header_cache[HEADER_MAP_OFFSET + i]);
 113
 114                 if (entry == SECTOR_DELETED)
 115                         continue;
 116
 117                 if (entry == SECTOR_FREE) {
 118                         block->free_sectors++;
 119                         continue;
 120                 }
 121
 122                 if (entry == SECTOR_ZERO)
 123                         entry = 0;
 124
 125                 if (entry >= part->sector_count) {
 126                         printk(KERN_WARNING PREFIX
 127                                 "'%s': unit #%d: entry %d corrupt, "
 128                                 "sector %d out of range\n",
 129                                 part->mbd.mtd->name, block_no, i, entry);
 130                         continue;
 131                 }
 132
 133                 if (part->sector_map[entry] != -1) {
 134                         printk(KERN_WARNING PREFIX
 135                                 "'%s': more than one entry for sector %d\n",
 136                                 part->mbd.mtd->name, entry);
 137                         part->errors = 1;
 138                         continue;
 139                 }
 140
 141                 part->sector_map[entry] = block->offset +
 142                         (i + part->header_sectors_per_block) * SECTOR_SIZE;
 143
 144                 block->used_sectors++;
 145         }
 146
 147         if (block->free_sectors == part->data_sectors_per_block)
 148                 part->reserved_block = block_no;
 149
 150         return 0;
 151 }
 152
 153 static int scan_header(struct partition *part)
 154 {
 155         int sectors_per_block;
 156         int i, rc = -ENOMEM;
 157         int blocks_found;
 158         size_t retlen;
 159
 160         sectors_per_block = part->block_size / SECTOR_SIZE;
 161         part->total_blocks = part->mbd.mtd->size / part->block_size;
 162
 163         if (part->total_blocks < 2)
 164                 return -ENOENT;
 165
 166         /* each erase block has three bytes header, followed by the map */
 167         part->header_sectors_per_block =
 168                         ((HEADER_MAP_OFFSET + sectors_per_block) *
 169                         sizeof(u16) + SECTOR_SIZE - 1) / SECTOR_SIZE;
 170
 171         part->data_sectors_per_block = sectors_per_block -
 172                         part->header_sectors_per_block;
 173
 174         part->header_size = (HEADER_MAP_OFFSET +
 175                         part->data_sectors_per_block) * sizeof(u16);
 176
 177         part->cylinders = (part->data_sectors_per_block *
 178                         (part->total_blocks - 1) - 1) / SECTORS_PER_TRACK;
 179
 180         part->sector_count = part->cylinders * SECTORS_PER_TRACK;
 181
 182         part->current_block = -1;
 183         part->reserved_block = -1;
 184         part->is_reclaiming = 0;
 185
 186         part->header_cache = kmalloc(part->header_size, GFP_KERNEL);
 187         if (!part->header_cache)
 188                 goto err;
 189
 190         part->blocks = kcalloc(part->total_blocks, sizeof(struct block),
 191                         GFP_KERNEL);
 192         if (!part->blocks)
 193                 goto err;
 194
 195         part->sector_map = vmalloc(part->sector_count * sizeof(u_long));
 196         if (!part->sector_map) {
 197                 printk(KERN_ERR PREFIX "'%s': unable to allocate memory for "
 198                         "sector map", part->mbd.mtd->name);
 199                 goto err;
 200         }
 201
 202         for (i=0; i<part->sector_count; i++)
 203                 part->sector_map[i] = -1;
 204
 205         for (i=0, blocks_found=0; i<part->total_blocks; i++) {
 206                 rc = part->mbd.mtd->read(part->mbd.mtd,
 207                                 i * part->block_size, part->header_size,
 208                                 &retlen, (u_char*)part->header_cache);
 209
 210                 if (!rc && retlen != part->header_size)
 211                         rc = -EIO;
 212
 213                 if (rc)
 214                         goto err;
 215
 216                 if (!build_block_map(part, i))
 217                         blocks_found++;
 218         }
 219
 220         if (blocks_found == 0) {
 221                 printk(KERN_NOTICE PREFIX "no RFD magic found in '%s'\n",
 222                                 part->mbd.mtd->name);
 223                 rc = -ENOENT;
 224                 goto err;
 225         }
 226
 227         if (part->reserved_block == -1) {
 228                 printk(KERN_WARNING PREFIX "'%s': no empty erase unit found\n",
 229                                 part->mbd.mtd->name);
 230
 231                 part->errors = 1;
 232         }
 233
 234         return 0;
 235
 236 err:
 237         vfree(part->sector_map);
 238         kfree(part->header_cache);
 239         kfree(part->blocks);
 240
 241         return rc;
 242 }
 243
 244 static int rfd_ftl_readsect(struct mtd_blktrans_dev *dev, u_long sector, char *buf)
 245 {
 246         struct partition *part = (struct partition*)dev;
 247         u_long addr;
 248         size_t retlen;
 249         int rc;
 250
 251         if (sector >= part->sector_count)
 252                 return -EIO;
 253
 254         addr = part->sector_map[sector];
 255         if (addr != -1) {
 256                 rc = part->mbd.mtd->read(part->mbd.mtd, addr, SECTOR_SIZE,
 257                                                 &retlen, (u_char*)buf);
 258                 if (!rc && retlen != SECTOR_SIZE)
 259                         rc = -EIO;
 260
 261                 if (rc) {
 262                         printk(KERN_WARNING PREFIX "error reading '%s' at "
 263                                 "0x%lx\n", part->mbd.mtd->name, addr);
 264                         return rc;
 265                 }
 266         } else
 267                 memset(buf, 0, SECTOR_SIZE);
 268
 269         return 0;
 270 }
 271
 272 static void erase_callback(struct erase_info *erase)
 273 {
 274         struct partition *part;
 275         u16 magic;
 276         int i, rc;
 277         size_t retlen;
 278
 279         part = (struct partition*)erase->priv;
 280
 281         i = erase->addr / part->block_size;
 282         if (i >= part->total_blocks || part->blocks[i].offset != erase->addr) {
 283                 printk(KERN_ERR PREFIX "erase callback for unknown offset %x "
 284                                 "on '%s'\n", erase->addr, part->mbd.mtd->name);
 285                 return;
 286         }
 287
 288         if (erase->state != MTD_ERASE_DONE) {
 289                 printk(KERN_WARNING PREFIX "erase failed at 0x%x on '%s', "
 290                                 "state %d\n", erase->addr,
 291                                 part->mbd.mtd->name, erase->state);
 292
 293                 part->blocks[i].state = BLOCK_FAILED;
 294                 part->blocks[i].free_sectors = 0;
 295                 part->blocks[i].used_sectors = 0;
 296
 297                 kfree(erase);
 298
 299                 return;
 300         }
 301
 302         magic = const_cpu_to_le16(RFD_MAGIC);
 303
 304         part->blocks[i].state = BLOCK_ERASED;
 305         part->blocks[i].free_sectors = part->data_sectors_per_block;
 306         part->blocks[i].used_sectors = 0;
 307         part->blocks[i].erases++;
 308
 309         rc = part->mbd.mtd->write(part->mbd.mtd,
 310                 part->blocks[i].offset, sizeof(magic), &retlen,
 311                 (u_char*)&magic);
 312
 313         if (!rc && retlen != sizeof(magic))
 314                 rc = -EIO;
 315
 316         if (rc) {
 317                 printk(KERN_ERR PREFIX "'%s': unable to write RFD "
 318                                 "header at 0x%lx\n",
 319                                 part->mbd.mtd->name,
 320                                 part->blocks[i].offset);
 321                 part->blocks[i].state = BLOCK_FAILED;
 322         }
 323         else
 324                 part->blocks[i].state = BLOCK_OK;
 325
 326         kfree(erase);
 327 }
 328
 329 static int erase_block(struct partition *part, int block)
 330 {
 331         struct erase_info *erase;
 332         int rc = -ENOMEM;
 333
 334         erase = kmalloc(sizeof(struct erase_info), GFP_KERNEL);
 335         if (!erase)
 336                 goto err;
 337
 338         erase->mtd = part->mbd.mtd;
 339         erase->callback = erase_callback;
 340         erase->addr = part->blocks[block].offset;
 341         erase->len = part->block_size;
 342         erase->priv = (u_long)part;
 343
 344         part->blocks[block].state = BLOCK_ERASING;
 345         part->blocks[block].free_sectors = 0;
 346
 347         rc = part->mbd.mtd->erase(part->mbd.mtd, erase);
 348
 349         if (rc) {
 350                 printk(KERN_ERR PREFIX "erase of region %x,%x on '%s' "
 351                                 "failed\n", erase->addr, erase->len,
 352                                 part->mbd.mtd->name);
 353                 kfree(erase);
 354         }
 355
 356 err:
 357         return rc;
 358 }
 359
 360 static int move_block_contents(struct partition *part, int block_no, u_long *old_sector)
 361 {
 362         void *sector_data;
 363         u16 *map;
 364         size_t retlen;
 365         int i, rc = -ENOMEM;
 366
 367         part->is_reclaiming = 1;
 368
 369         sector_data = kmalloc(SECTOR_SIZE, GFP_KERNEL);
 370         if (!sector_data)
 371                 goto err3;
 372
 373         map = kmalloc(part->header_size, GFP_KERNEL);
 374         if (!map)
 375                 goto err2;
 376
 377         rc = part->mbd.mtd->read(part->mbd.mtd,
 378                 part->blocks[block_no].offset, part->header_size,
 379                 &retlen, (u_char*)map);
 380
 381         if (!rc && retlen != part->header_size)
 382                 rc = -EIO;
 383
 384         if (rc) {
 385                 printk(KERN_ERR PREFIX "error reading '%s' at "
 386                         "0x%lx\n", part->mbd.mtd->name,
 387                         part->blocks[block_no].offset);
 388
 389                 goto err;
 390         }
 391
 392         for (i=0; i<part->data_sectors_per_block; i++) {
 393                 u16 entry = le16_to_cpu(map[HEADER_MAP_OFFSET + i]);
 394                 u_long addr;
 395
 396
 397                 if (entry == SECTOR_FREE || entry == SECTOR_DELETED)
 398                         continue;
 399
 400                 if (entry == SECTOR_ZERO)
 401                         entry = 0;
 402
 403                 /* already warned about and ignored in build_block_map() */
 404                 if (entry >= part->sector_count)
 405                         continue;
 406
 407                 addr = part->blocks[block_no].offset +
 408                         (i + part->header_sectors_per_block) * SECTOR_SIZE;
 409
 410                 if (*old_sector == addr) {
 411                         *old_sector = -1;
 412                         if (!part->blocks[block_no].used_sectors--) {
 413                                 rc = erase_block(part, block_no);
 414                                 break;
 415                         }
 416                         continue;
 417                 }
 418                 rc = part->mbd.mtd->read(part->mbd.mtd, addr,
 419                         SECTOR_SIZE, &retlen, sector_data);
 420
 421                 if (!rc && retlen != SECTOR_SIZE)
 422                         rc = -EIO;
 423
 424                 if (rc) {
 425                         printk(KERN_ERR PREFIX "'%s': Unable to "
 426                                 "read sector for relocation\n",
 427                                 part->mbd.mtd->name);
 428
 429                         goto err;
 430                 }
 431
 432                 rc = rfd_ftl_writesect((struct mtd_blktrans_dev*)part,
 433                                 entry, sector_data);
 434
 435                 if (rc)
 436                         goto err;
 437         }
 438
 439 err:
 440         kfree(map);
 441 err2:
 442         kfree(sector_data);
 443 err3:
 444         part->is_reclaiming = 0;
 445
 446         return rc;
 447 }
 448
 449 static int reclaim_block(struct partition *part, u_long *old_sector)
 450 {
 451         int block, best_block, score, old_sector_block;
 452         int rc;
 453
 454         /* we have a race if sync doesn't exist */
 455         if (part->mbd.mtd->sync)
 456                 part->mbd.mtd->sync(part->mbd.mtd);
 457
 458         score = 0x7fffffff; /* MAX_INT */
 459         best_block = -1;
 460         if (*old_sector != -1)
 461                 old_sector_block = *old_sector / part->block_size;
 462         else
 463                 old_sector_block = -1;
 464
 465         for (block=0; block<part->total_blocks; block++) {
 466                 int this_score;
 467
 468                 if (block == part->reserved_block)
 469                         continue;
 470
 471                 /*
 472                  * Postpone reclaiming if there is a free sector as
 473                  * more removed sectors is more efficient (have to move
 474                  * less).
 475                  */
 476                 if (part->blocks[block].free_sectors)
 477                         return 0;
 478
 479                 this_score = part->blocks[block].used_sectors;
 480
 481                 if (block == old_sector_block)
 482                         this_score--;
 483                 else {
 484                         /* no point in moving a full block */
 485                         if (part->blocks[block].used_sectors ==
 486                                         part->data_sectors_per_block)
 487                                 continue;
 488                 }
 489
 490                 this_score += part->blocks[block].erases;
 491
 492                 if (this_score < score) {
 493                         best_block = block;
 494                         score = this_score;
 495                 }
 496         }
 497
 498         if (best_block == -1)
 499                 return -ENOSPC;
 500
 501         part->current_block = -1;
 502         part->reserved_block = best_block;
 503
 504         pr_debug("reclaim_block: reclaiming block #%d with %d used "
 505                  "%d free sectors\n", best_block,
 506                  part->blocks[best_block].used_sectors,
 507                  part->blocks[best_block].free_sectors);
 508
 509         if (part->blocks[best_block].used_sectors)
 510                 rc = move_block_contents(part, best_block, old_sector);
 511         else
 512                 rc = erase_block(part, best_block);
 513
 514         return rc;
 515 }
 516
 517 /*
 518  * IMPROVE: It would be best to choose the block with the most deleted sectors,
 519  * because if we fill that one up first it'll have the most chance of having
 520  * the least live sectors at reclaim.
 521  */
 522 static int find_free_block(struct partition *part)
 523 {
 524         int block, stop;
 525
 526         block = part->current_block == -1 ?
 527                         jiffies % part->total_blocks : part->current_block;
 528         stop = block;
 529
 530         do {
 531                 if (part->blocks[block].free_sectors &&
 532                                 block != part->reserved_block)
 533                         return block;
 534
 535                 if (part->blocks[block].state == BLOCK_UNUSED)
 536                         erase_block(part, block);
 537
 538                 if (++block >= part->total_blocks)
 539                         block = 0;
 540
 541         } while (block != stop);
 542
 543         return -1;
 544 }
 545
 546 static int find_writable_block(struct partition *part, u_long *old_sector)
 547 {
 548         int rc, block;
 549         size_t retlen;
 550
 551         block = find_free_block(part);
 552
 553         if (block == -1) {
 554                 if (!part->is_reclaiming) {
 555                         rc = reclaim_block(part, old_sector);
 556                         if (rc)
 557                                 goto err;
 558
 559                         block = find_free_block(part);
 560                 }
 561
 562                 if (block == -1) {
 563                         rc = -ENOSPC;
 564                         goto err;
 565                 }
 566         }
 567
 568         rc = part->mbd.mtd->read(part->mbd.mtd, part->blocks[block].offset,
 569                 part->header_size, &retlen, (u_char*)part->header_cache);
 570
 571         if (!rc && retlen != part->header_size)
 572                 rc = -EIO;
 573
 574         if (rc) {
 575                 printk(KERN_ERR PREFIX "'%s': unable to read header at "
 576                                 "0x%lx\n", part->mbd.mtd->name,
 577                                 part->blocks[block].offset);
 578                 goto err;
 579         }
 580
 581         part->current_block = block;
 582
 583 err:
 584         return rc;
 585 }
 586
 587 static int mark_sector_deleted(struct partition *part, u_long old_addr)
 588 {
 589         int block, offset, rc;
 590         u_long addr;
 591         size_t retlen;
 592         u16 del = const_cpu_to_le16(SECTOR_DELETED);
 593
 594         block = old_addr / part->block_size;
 595         offset = (old_addr % part->block_size) / SECTOR_SIZE -
 596                 part->header_sectors_per_block;
 597
 598         addr = part->blocks[block].offset +
 599                         (HEADER_MAP_OFFSET + offset) * sizeof(u16);
 600         rc = part->mbd.mtd->write(part->mbd.mtd, addr,
 601                 sizeof(del), &retlen, (u_char*)&del);
 602
 603         if (!rc && retlen != sizeof(del))
 604                 rc = -EIO;
 605
 606         if (rc) {
 607                 printk(KERN_ERR PREFIX "error writing '%s' at "
 608                         "0x%lx\n", part->mbd.mtd->name, addr);
 609                 if (rc)
 610                         goto err;
 611         }
 612         if (block == part->current_block)
 613                 part->header_cache[offset + HEADER_MAP_OFFSET] = del;
 614
 615         part->blocks[block].used_sectors--;
 616
 617         if (!part->blocks[block].used_sectors &&
 618             !part->blocks[block].free_sectors)
 619                 rc = erase_block(part, block);
 620
 621 err:
 622         return rc;
 623 }
 624
 625 static int find_free_sector(const struct partition *part, const struct block *block)
 626 {
 627         int i, stop;
 628
 629         i = stop = part->data_sectors_per_block - block->free_sectors;
 630
 631         do {
 632                 if (le16_to_cpu(part->header_cache[HEADER_MAP_OFFSET + i])
 633                                 == SECTOR_FREE)
 634                         return i;
 635
 636                 if (++i == part->data_sectors_per_block)
 637                         i = 0;
 638         }
 639         while(i != stop);
 640
 641         return -1;
 642 }
 643
 644 static int do_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf, ulong *old_addr)
 645 {
 646         struct partition *part = (struct partition*)dev;
 647         struct block *block;
 648         u_long addr;
 649         int i;
 650         int rc;
 651         size_t retlen;
 652         u16 entry;
 653
 654         if (part->current_block == -1 ||
 655                 !part->blocks[part->current_block].free_sectors) {
 656
 657                 rc = find_writable_block(part, old_addr);
 658                 if (rc)
 659                         goto err;
 660         }
 661
 662         block = &part->blocks[part->current_block];
 663
 664         i = find_free_sector(part, block);
 665
 666         if (i < 0) {
 667                 rc = -ENOSPC;
 668                 goto err;
 669         }
 670
 671         addr = (i + part->header_sectors_per_block) * SECTOR_SIZE +
 672                 block->offset;
 673         rc = part->mbd.mtd->write(part->mbd.mtd,
 674                 addr, SECTOR_SIZE, &retlen, (u_char*)buf);
 675
 676         if (!rc && retlen != SECTOR_SIZE)
 677                 rc = -EIO;
 678
 679         if (rc) {
 680                 printk(KERN_ERR PREFIX "error writing '%s' at 0x%lx\n",
 681                                 part->mbd.mtd->name, addr);
 682                 if (rc)
 683                         goto err;
 684         }
 685
 686         part->sector_map[sector] = addr;
 687
 688         entry = cpu_to_le16(sector == 0 ? SECTOR_ZERO : sector);
 689
 690         part->header_cache[i + HEADER_MAP_OFFSET] = entry;
 691
 692         addr = block->offset + (HEADER_MAP_OFFSET + i) * sizeof(u16);
 693         rc = part->mbd.mtd->write(part->mbd.mtd, addr,
 694                         sizeof(entry), &retlen, (u_char*)&entry);
 695
 696         if (!rc && retlen != sizeof(entry))
 697                 rc = -EIO;
 698
 699         if (rc) {
 700                 printk(KERN_ERR PREFIX "error writing '%s' at 0x%lx\n",
 701                                 part->mbd.mtd->name, addr);
 702                 if (rc)
 703                         goto err;
 704         }
 705         block->used_sectors++;
 706         block->free_sectors--;
 707
 708 err:
 709         return rc;
 710 }
 711
 712 static int rfd_ftl_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf)
 713 {
 714         struct partition *part = (struct partition*)dev;
 715         u_long old_addr;
 716         int i;
 717         int rc = 0;
 718
 719         pr_debug("rfd_ftl_writesect(sector=0x%lx)\n", sector);
 720
 721         if (part->reserved_block == -1) {
 722                 rc = -EACCES;
 723                 goto err;
 724         }
 725
 726         if (sector >= part->sector_count) {
 727                 rc = -EIO;
 728                 goto err;
 729         }
 730
 731         old_addr = part->sector_map[sector];
 732
 733         for (i=0; i<SECTOR_SIZE; i++) {
 734                 if (!buf[i])
 735                         continue;
 736
 737                 rc = do_writesect(dev, sector, buf, &old_addr);
 738                 if (rc)
 739                         goto err;
 740                 break;
 741         }
 742
 743         if (i == SECTOR_SIZE)
 744                 part->sector_map[sector] = -1;
 745
 746         if (old_addr != -1)
 747                 rc = mark_sector_deleted(part, old_addr);
 748
 749 err:
 750         return rc;
 751 }
 752
 753 static int rfd_ftl_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
 754 {
 755         struct partition *part = (struct partition*)dev;
 756
 757         geo->heads = 1;
 758         geo->sectors = SECTORS_PER_TRACK;
 759         geo->cylinders = part->cylinders;
 760
 761         return 0;
 762 }
 763
 764 static void rfd_ftl_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
 765 {
 766         struct partition *part;
 767
 768         if (mtd->type != MTD_NORFLASH)
 769                 return;
 770
 771         part = kcalloc(1, sizeof(struct partition), GFP_KERNEL);
 772         if (!part)
 773                 return;
 774
 775         part->mbd.mtd = mtd;
 776
 777         if (block_size)
 778                 part->block_size = block_size;
 779         else {
 780                 if (!mtd->erasesize) {
 781                         printk(KERN_WARNING PREFIX "please provide block_size");
 782                         return;
 783                 }
 784                 else
 785                         part->block_size = mtd->erasesize;
 786         }
 787
 788         if (scan_header(part) == 0) {
 789                 part->mbd.size = part->sector_count;
 790                 part->mbd.blksize = SECTOR_SIZE;
 791                 part->mbd.tr = tr;
 792                 part->mbd.devnum = -1;
 793                 if (!(mtd->flags & MTD_WRITEABLE))
 794                         part->mbd.readonly = 1;
 795                 else if (part->errors) {
 796                         printk(KERN_WARNING PREFIX "'%s': errors found, "
 797                                         "setting read-only\n", mtd->name);
 798                         part->mbd.readonly = 1;
 799                 }
 800
 801                 printk(KERN_INFO PREFIX "name: '%s' type: %d flags %x\n",
 802                                 mtd->name, mtd->type, mtd->flags);
 803
 804                 if (!add_mtd_blktrans_dev((void*)part))
 805                         return;
 806         }
 807
 808         kfree(part);
 809 }
 810
 811 static void rfd_ftl_remove_dev(struct mtd_blktrans_dev *dev)
 812 {
 813         struct partition *part = (struct partition*)dev;
 814         int i;
 815
 816         for (i=0; i<part->total_blocks; i++) {
 817                 pr_debug("rfd_ftl_remove_dev:'%s': erase unit #%02d: %d erases\n",
 818                         part->mbd.mtd->name, i, part->blocks[i].erases);
 819         }
 820
 821         del_mtd_blktrans_dev(dev);
 822         vfree(part->sector_map);
 823         kfree(part->header_cache);
 824         kfree(part->blocks);
 825         kfree(part);
 826 }
 827
 828 struct mtd_blktrans_ops rfd_ftl_tr = {
 829         .name           = "rfd",
 830         .major          = RFD_FTL_MAJOR,
 831         .part_bits      = PART_BITS,
 832         .readsect       = rfd_ftl_readsect,
 833         .writesect      = rfd_ftl_writesect,
 834         .getgeo         = rfd_ftl_getgeo,
 835         .add_mtd        = rfd_ftl_add_mtd,
 836         .remove_dev     = rfd_ftl_remove_dev,
 837         .owner          = THIS_MODULE,
 838 };
 839
 840 static int __init init_rfd_ftl(void)
 841 {
 842         return register_mtd_blktrans(&rfd_ftl_tr);
 843 }
 844
 845 static void __exit cleanup_rfd_ftl(void)
 846 {
 847         deregister_mtd_blktrans(&rfd_ftl_tr);
 848 }
 849
 850 module_init(init_rfd_ftl);
 851 module_exit(cleanup_rfd_ftl);
 852
 853 MODULE_LICENSE("GPL");
 854 MODULE_AUTHOR("Sean Young <sean@mess.org>");
 855 MODULE_DESCRIPTION("Support code for RFD Flash Translation Layer, "
 856                 "used by General Software's Embedded BIOS");
 857