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