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