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