drivers/mtd/mtdpart.c

   1 /*
   2  * Simple MTD partitioning layer
   3  *
   4  * (C) 2000 Nicolas Pitre <nico@cam.org>
   5  *
   6  * This code is GPL
   7  *
   8  *      02-21-2002      Thomas Gleixner <gleixner@autronix.de>
   9  *                      added support for read_oob, write_oob
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/types.h>
  14 #include <linux/kernel.h>
  15 #include <linux/slab.h>
  16 #include <linux/list.h>
  17 #include <linux/kmod.h>
  18 #include <linux/mtd/mtd.h>
  19 #include <linux/mtd/partitions.h>
  20 #include <linux/mtd/compatmac.h>
  21
  22 /* Our partition linked list */
  23 static LIST_HEAD(mtd_partitions);
  24
  25 /* Our partition node structure */
  26 struct mtd_part {
  27         struct mtd_info mtd;
  28         struct mtd_info *master;
  29         uint64_t offset;
  30         int index;
  31         struct list_head list;
  32         int registered;
  33 };
  34
  35 /*
  36  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
  37  * the pointer to that structure with this macro.
  38  */
  39 #define PART(x)  ((struct mtd_part *)(x))
  40
  41
  42 /*
  43  * MTD methods which simply translate the effective address and pass through
  44  * to the _real_ device.
  45  */
  46
  47 static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
  48                 size_t *retlen, u_char *buf)
  49 {
  50         struct mtd_part *part = PART(mtd);
  51         struct mtd_ecc_stats stats;
  52         int res;
  53
  54         stats = part->master->ecc_stats;
  55
  56         if (from >= mtd->size)
  57                 len = 0;
  58         else if (from + len > mtd->size)
  59                 len = mtd->size - from;
  60         res = part->master->read(part->master, from + part->offset,
  61                                    len, retlen, buf);
  62         if (unlikely(res)) {
  63                 if (res == -EUCLEAN)
  64                         mtd->ecc_stats.corrected += part->master->ecc_stats.corrected - stats.corrected;
  65                 if (res == -EBADMSG)
  66                         mtd->ecc_stats.failed += part->master->ecc_stats.failed - stats.failed;
  67         }
  68         return res;
  69 }
  70
  71 static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
  72                 size_t *retlen, void **virt, resource_size_t *phys)
  73 {
  74         struct mtd_part *part = PART(mtd);
  75         if (from >= mtd->size)
  76                 len = 0;
  77         else if (from + len > mtd->size)
  78                 len = mtd->size - from;
  79         return part->master->point (part->master, from + part->offset,
  80                                     len, retlen, virt, phys);
  81 }
  82
  83 static void part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
  84 {
  85         struct mtd_part *part = PART(mtd);
  86
  87         part->master->unpoint(part->master, from + part->offset, len);
  88 }
  89
  90 static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
  91                                             unsigned long len,
  92                                             unsigned long offset,
  93                                             unsigned long flags)
  94 {
  95         struct mtd_part *part = PART(mtd);
  96
  97         offset += part->offset;
  98         return part->master->get_unmapped_area(part->master, len, offset,
  99                                                flags);
 100 }
 101
 102 static int part_read_oob(struct mtd_info *mtd, loff_t from,
 103                 struct mtd_oob_ops *ops)
 104 {
 105         struct mtd_part *part = PART(mtd);
 106         int res;
 107
 108         if (from >= mtd->size)
 109                 return -EINVAL;
 110         if (ops->datbuf && from + ops->len > mtd->size)
 111                 return -EINVAL;
 112         res = part->master->read_oob(part->master, from + part->offset, ops);
 113
 114         if (unlikely(res)) {
 115                 if (res == -EUCLEAN)
 116                         mtd->ecc_stats.corrected++;
 117                 if (res == -EBADMSG)
 118                         mtd->ecc_stats.failed++;
 119         }
 120         return res;
 121 }
 122
 123 static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
 124                 size_t len, size_t *retlen, u_char *buf)
 125 {
 126         struct mtd_part *part = PART(mtd);
 127         return part->master->read_user_prot_reg(part->master, from,
 128                                         len, retlen, buf);
 129 }
 130
 131 static int part_get_user_prot_info(struct mtd_info *mtd,
 132                 struct otp_info *buf, size_t len)
 133 {
 134         struct mtd_part *part = PART(mtd);
 135         return part->master->get_user_prot_info(part->master, buf, len);
 136 }
 137
 138 static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
 139                 size_t len, size_t *retlen, u_char *buf)
 140 {
 141         struct mtd_part *part = PART(mtd);
 142         return part->master->read_fact_prot_reg(part->master, from,
 143                                         len, retlen, buf);
 144 }
 145
 146 static int part_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
 147                 size_t len)
 148 {
 149         struct mtd_part *part = PART(mtd);
 150         return part->master->get_fact_prot_info(part->master, buf, len);
 151 }
 152
 153 static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
 154                 size_t *retlen, const u_char *buf)
 155 {
 156         struct mtd_part *part = PART(mtd);
 157         if (!(mtd->flags & MTD_WRITEABLE))
 158                 return -EROFS;
 159         if (to >= mtd->size)
 160                 len = 0;
 161         else if (to + len > mtd->size)
 162                 len = mtd->size - to;
 163         return part->master->write(part->master, to + part->offset,
 164                                     len, retlen, buf);
 165 }
 166
 167 static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
 168                 size_t *retlen, const u_char *buf)
 169 {
 170         struct mtd_part *part = PART(mtd);
 171         if (!(mtd->flags & MTD_WRITEABLE))
 172                 return -EROFS;
 173         if (to >= mtd->size)
 174                 len = 0;
 175         else if (to + len > mtd->size)
 176                 len = mtd->size - to;
 177         return part->master->panic_write(part->master, to + part->offset,
 178                                     len, retlen, buf);
 179 }
 180
 181 static int part_write_oob(struct mtd_info *mtd, loff_t to,
 182                 struct mtd_oob_ops *ops)
 183 {
 184         struct mtd_part *part = PART(mtd);
 185
 186         if (!(mtd->flags & MTD_WRITEABLE))
 187                 return -EROFS;
 188
 189         if (to >= mtd->size)
 190                 return -EINVAL;
 191         if (ops->datbuf && to + ops->len > mtd->size)
 192                 return -EINVAL;
 193         return part->master->write_oob(part->master, to + part->offset, ops);
 194 }
 195
 196 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
 197                 size_t len, size_t *retlen, u_char *buf)
 198 {
 199         struct mtd_part *part = PART(mtd);
 200         return part->master->write_user_prot_reg(part->master, from,
 201                                         len, retlen, buf);
 202 }
 203
 204 static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
 205                 size_t len)
 206 {
 207         struct mtd_part *part = PART(mtd);
 208         return part->master->lock_user_prot_reg(part->master, from, len);
 209 }
 210
 211 static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
 212                 unsigned long count, loff_t to, size_t *retlen)
 213 {
 214         struct mtd_part *part = PART(mtd);
 215         if (!(mtd->flags & MTD_WRITEABLE))
 216                 return -EROFS;
 217         return part->master->writev(part->master, vecs, count,
 218                                         to + part->offset, retlen);
 219 }
 220
 221 static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
 222 {
 223         struct mtd_part *part = PART(mtd);
 224         int ret;
 225         if (!(mtd->flags & MTD_WRITEABLE))
 226                 return -EROFS;
 227         if (instr->addr >= mtd->size)
 228                 return -EINVAL;
 229         instr->addr += part->offset;
 230         ret = part->master->erase(part->master, instr);
 231         if (ret) {
 232                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 233                         instr->fail_addr -= part->offset;
 234                 instr->addr -= part->offset;
 235         }
 236         return ret;
 237 }
 238
 239 void mtd_erase_callback(struct erase_info *instr)
 240 {
 241         if (instr->mtd->erase == part_erase) {
 242                 struct mtd_part *part = PART(instr->mtd);
 243
 244                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 245                         instr->fail_addr -= part->offset;
 246                 instr->addr -= part->offset;
 247         }
 248         if (instr->callback)
 249                 instr->callback(instr);
 250 }
 251 EXPORT_SYMBOL_GPL(mtd_erase_callback);
 252
 253 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 254 {
 255         struct mtd_part *part = PART(mtd);
 256         if ((len + ofs) > mtd->size)
 257                 return -EINVAL;
 258         return part->master->lock(part->master, ofs + part->offset, len);
 259 }
 260
 261 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 262 {
 263         struct mtd_part *part = PART(mtd);
 264         if ((len + ofs) > mtd->size)
 265                 return -EINVAL;
 266         return part->master->unlock(part->master, ofs + part->offset, len);
 267 }
 268
 269 static void part_sync(struct mtd_info *mtd)
 270 {
 271         struct mtd_part *part = PART(mtd);
 272         part->master->sync(part->master);
 273 }
 274
 275 static int part_suspend(struct mtd_info *mtd)
 276 {
 277         struct mtd_part *part = PART(mtd);
 278         return part->master->suspend(part->master);
 279 }
 280
 281 static void part_resume(struct mtd_info *mtd)
 282 {
 283         struct mtd_part *part = PART(mtd);
 284         part->master->resume(part->master);
 285 }
 286
 287 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
 288 {
 289         struct mtd_part *part = PART(mtd);
 290         if (ofs >= mtd->size)
 291                 return -EINVAL;
 292         ofs += part->offset;
 293         return part->master->block_isbad(part->master, ofs);
 294 }
 295
 296 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
 297 {
 298         struct mtd_part *part = PART(mtd);
 299         int res;
 300
 301         if (!(mtd->flags & MTD_WRITEABLE))
 302                 return -EROFS;
 303         if (ofs >= mtd->size)
 304                 return -EINVAL;
 305         ofs += part->offset;
 306         res = part->master->block_markbad(part->master, ofs);
 307         if (!res)
 308                 mtd->ecc_stats.badblocks++;
 309         return res;
 310 }
 311
 312 /*
 313  * This function unregisters and destroy all slave MTD objects which are
 314  * attached to the given master MTD object.
 315  */
 316
 317 int del_mtd_partitions(struct mtd_info *master)
 318 {
 319         struct mtd_part *slave, *next;
 320
 321         list_for_each_entry_safe(slave, next, &mtd_partitions, list)
 322                 if (slave->master == master) {
 323                         list_del(&slave->list);
 324                         if (slave->registered)
 325                                 del_mtd_device(&slave->mtd);
 326                         kfree(slave);
 327                 }
 328
 329         return 0;
 330 }
 331 EXPORT_SYMBOL(del_mtd_partitions);
 332
 333 static struct mtd_part *add_one_partition(struct mtd_info *master,
 334                 const struct mtd_partition *part, int partno,
 335                 uint64_t cur_offset)
 336 {
 337         struct mtd_part *slave;
 338
 339         /* allocate the partition structure */
 340         slave = kzalloc(sizeof(*slave), GFP_KERNEL);
 341         if (!slave) {
 342                 printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
 343                         master->name);
 344                 del_mtd_partitions(master);
 345                 return NULL;
 346         }
 347         list_add(&slave->list, &mtd_partitions);
 348
 349         /* set up the MTD object for this partition */
 350         slave->mtd.type = master->type;
 351         slave->mtd.flags = master->flags & ~part->mask_flags;
 352         slave->mtd.size = part->size;
 353         slave->mtd.writesize = master->writesize;
 354         slave->mtd.oobsize = master->oobsize;
 355         slave->mtd.oobavail = master->oobavail;
 356         slave->mtd.subpage_sft = master->subpage_sft;
 357
 358         slave->mtd.name = part->name;
 359         slave->mtd.owner = master->owner;
 360         slave->mtd.backing_dev_info = master->backing_dev_info;
 361
 362         /* NOTE:  we don't arrange MTDs as a tree; it'd be error-prone
 363          * to have the same data be in two different partitions.
 364          */
 365         slave->mtd.dev.parent = master->dev.parent;
 366
 367         slave->mtd.read = part_read;
 368         slave->mtd.write = part_write;
 369
 370         if (master->panic_write)
 371                 slave->mtd.panic_write = part_panic_write;
 372
 373         if (master->point && master->unpoint) {
 374                 slave->mtd.point = part_point;
 375                 slave->mtd.unpoint = part_unpoint;
 376         }
 377
 378         if (master->get_unmapped_area)
 379                 slave->mtd.get_unmapped_area = part_get_unmapped_area;
 380         if (master->read_oob)
 381                 slave->mtd.read_oob = part_read_oob;
 382         if (master->write_oob)
 383                 slave->mtd.write_oob = part_write_oob;
 384         if (master->read_user_prot_reg)
 385                 slave->mtd.read_user_prot_reg = part_read_user_prot_reg;
 386         if (master->read_fact_prot_reg)
 387                 slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg;
 388         if (master->write_user_prot_reg)
 389                 slave->mtd.write_user_prot_reg = part_write_user_prot_reg;
 390         if (master->lock_user_prot_reg)
 391                 slave->mtd.lock_user_prot_reg = part_lock_user_prot_reg;
 392         if (master->get_user_prot_info)
 393                 slave->mtd.get_user_prot_info = part_get_user_prot_info;
 394         if (master->get_fact_prot_info)
 395                 slave->mtd.get_fact_prot_info = part_get_fact_prot_info;
 396         if (master->sync)
 397                 slave->mtd.sync = part_sync;
 398         if (!partno && master->suspend && master->resume) {
 399                         slave->mtd.suspend = part_suspend;
 400                         slave->mtd.resume = part_resume;
 401         }
 402         if (master->writev)
 403                 slave->mtd.writev = part_writev;
 404         if (master->lock)
 405                 slave->mtd.lock = part_lock;
 406         if (master->unlock)
 407                 slave->mtd.unlock = part_unlock;
 408         if (master->block_isbad)
 409                 slave->mtd.block_isbad = part_block_isbad;
 410         if (master->block_markbad)
 411                 slave->mtd.block_markbad = part_block_markbad;
 412         slave->mtd.erase = part_erase;
 413         slave->master = master;
 414         slave->offset = part->offset;
 415         slave->index = partno;
 416
 417         if (slave->offset == MTDPART_OFS_APPEND)
 418                 slave->offset = cur_offset;
 419         if (slave->offset == MTDPART_OFS_NXTBLK) {
 420                 slave->offset = cur_offset;
 421                 if (mtd_mod_by_eb(cur_offset, master) != 0) {
 422                         /* Round up to next erasesize */
 423                         slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
 424                         printk(KERN_NOTICE "Moving partition %d: "
 425                                "0x%012llx -> 0x%012llx\n", partno,
 426                                (unsigned long long)cur_offset, (unsigned long long)slave->offset);
 427                 }
 428         }
 429         if (slave->mtd.size == MTDPART_SIZ_FULL)
 430                 slave->mtd.size = master->size - slave->offset;
 431
 432         printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
 433                 (unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
 434
 435         /* let's do some sanity checks */
 436         if (slave->offset >= master->size) {
 437                 /* let's register it anyway to preserve ordering */
 438                 slave->offset = 0;
 439                 slave->mtd.size = 0;
 440                 printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
 441                         part->name);
 442                 goto out_register;
 443         }
 444         if (slave->offset + slave->mtd.size > master->size) {
 445                 slave->mtd.size = master->size - slave->offset;
 446                 printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
 447                         part->name, master->name, (unsigned long long)slave->mtd.size);
 448         }
 449         if (master->numeraseregions > 1) {
 450                 /* Deal with variable erase size stuff */
 451                 int i, max = master->numeraseregions;
 452                 u64 end = slave->offset + slave->mtd.size;
 453                 struct mtd_erase_region_info *regions = master->eraseregions;
 454
 455                 /* Find the first erase regions which is part of this
 456                  * partition. */
 457                 for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
 458                         ;
 459                 /* The loop searched for the region _behind_ the first one */
 460                 i--;
 461
 462                 /* Pick biggest erasesize */
 463                 for (; i < max && regions[i].offset < end; i++) {
 464                         if (slave->mtd.erasesize < regions[i].erasesize) {
 465                                 slave->mtd.erasesize = regions[i].erasesize;
 466                         }
 467                 }
 468                 BUG_ON(slave->mtd.erasesize == 0);
 469         } else {
 470                 /* Single erase size */
 471                 slave->mtd.erasesize = master->erasesize;
 472         }
 473
 474         if ((slave->mtd.flags & MTD_WRITEABLE) &&
 475             mtd_mod_by_eb(slave->offset, &slave->mtd)) {
 476                 /* Doesn't start on a boundary of major erase size */
 477                 /* FIXME: Let it be writable if it is on a boundary of
 478                  * _minor_ erase size though */
 479                 slave->mtd.flags &= ~MTD_WRITEABLE;
 480                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
 481                         part->name);
 482         }
 483         if ((slave->mtd.flags & MTD_WRITEABLE) &&
 484             mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
 485                 slave->mtd.flags &= ~MTD_WRITEABLE;
 486                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
 487                         part->name);
 488         }
 489
 490         slave->mtd.ecclayout = master->ecclayout;
 491         if (master->block_isbad) {
 492                 uint64_t offs = 0;
 493
 494                 while (offs < slave->mtd.size) {
 495                         if (master->block_isbad(master,
 496                                                 offs + slave->offset))
 497                                 slave->mtd.ecc_stats.badblocks++;
 498                         offs += slave->mtd.erasesize;
 499                 }
 500         }
 501
 502 out_register:
 503         if (part->mtdp) {
 504                 /* store the object pointer (caller may or may not register it*/
 505                 *part->mtdp = &slave->mtd;
 506                 slave->registered = 0;
 507         } else {
 508                 /* register our partition */
 509                 add_mtd_device(&slave->mtd);
 510                 slave->registered = 1;
 511         }
 512         return slave;
 513 }
 514
 515 /*
 516  * This function, given a master MTD object and a partition table, creates
 517  * and registers slave MTD objects which are bound to the master according to
 518  * the partition definitions.
 519  *
 520  * We don't register the master, or expect the caller to have done so,
 521  * for reasons of data integrity.
 522  */
 523
 524 int add_mtd_partitions(struct mtd_info *master,
 525                        const struct mtd_partition *parts,
 526                        int nbparts)
 527 {
 528         struct mtd_part *slave;
 529         uint64_t cur_offset = 0;
 530         int i;
 531
 532         printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
 533
 534         for (i = 0; i < nbparts; i++) {
 535                 slave = add_one_partition(master, parts + i, i, cur_offset);
 536                 if (!slave)
 537                         return -ENOMEM;
 538                 cur_offset = slave->offset + slave->mtd.size;
 539         }
 540
 541         return 0;
 542 }
 543 EXPORT_SYMBOL(add_mtd_partitions);
 544
 545 static DEFINE_SPINLOCK(part_parser_lock);
 546 static LIST_HEAD(part_parsers);
 547
 548 static struct mtd_part_parser *get_partition_parser(const char *name)
 549 {
 550         struct mtd_part_parser *p, *ret = NULL;
 551
 552         spin_lock(&part_parser_lock);
 553
 554         list_for_each_entry(p, &part_parsers, list)
 555                 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
 556                         ret = p;
 557                         break;
 558                 }
 559
 560         spin_unlock(&part_parser_lock);
 561
 562         return ret;
 563 }
 564
 565 int register_mtd_parser(struct mtd_part_parser *p)
 566 {
 567         spin_lock(&part_parser_lock);
 568         list_add(&p->list, &part_parsers);
 569         spin_unlock(&part_parser_lock);
 570
 571         return 0;
 572 }
 573 EXPORT_SYMBOL_GPL(register_mtd_parser);
 574
 575 int deregister_mtd_parser(struct mtd_part_parser *p)
 576 {
 577         spin_lock(&part_parser_lock);
 578         list_del(&p->list);
 579         spin_unlock(&part_parser_lock);
 580         return 0;
 581 }
 582 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
 583
 584 int parse_mtd_partitions(struct mtd_info *master, const char **types,
 585                          struct mtd_partition **pparts, unsigned long origin)
 586 {
 587         struct mtd_part_parser *parser;
 588         int ret = 0;
 589
 590         for ( ; ret <= 0 && *types; types++) {
 591                 parser = get_partition_parser(*types);
 592                 if (!parser && !request_module("%s", *types))
 593                                 parser = get_partition_parser(*types);
 594                 if (!parser) {
 595                         printk(KERN_NOTICE "%s partition parsing not available\n",
 596                                *types);
 597                         continue;
 598                 }
 599                 ret = (*parser->parse_fn)(master, pparts, origin);
 600                 if (ret > 0) {
 601                         printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
 602                                ret, parser->name, master->name);
 603                 }
 604                 put_partition_parser(parser);
 605         }
 606         return ret;
 607 }
 608 EXPORT_SYMBOL_GPL(parse_mtd_partitions);