drivers/mtd/mtdpart.c

   1 /*
   2  * Simple MTD partitioning layer
   3  *
   4  * Copyright © 2000 Nicolas Pitre <nico@fluxnic.net>
   5  * Copyright © 2002 Thomas Gleixner <gleixner@linutronix.de>
   6  * Copyright © 2000-2010 David Woodhouse <dwmw2@infradead.org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  21  *
  22  */
  23
  24 #include <linux/module.h>
  25 #include <linux/types.h>
  26 #include <linux/kernel.h>
  27 #include <linux/slab.h>
  28 #include <linux/list.h>
  29 #include <linux/kmod.h>
  30 #include <linux/mtd/mtd.h>
  31 #include <linux/mtd/partitions.h>
  32 #include <linux/err.h>
  33
  34 #include "mtdcore.h"
  35
  36 /* Our partition linked list */
  37 static LIST_HEAD(mtd_partitions);
  38 static DEFINE_MUTEX(mtd_partitions_mutex);
  39
  40 /**
  41  * struct mtd_part - our partition node structure
  42  *
  43  * @mtd: struct holding partition details
  44  * @parent: parent mtd - flash device or another partition
  45  * @offset: partition offset relative to the *flash device*
  46  */
  47 struct mtd_part {
  48         struct mtd_info mtd;
  49         struct mtd_info *parent;
  50         uint64_t offset;
  51         struct list_head list;
  52 };
  53
  54 /*
  55  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
  56  * the pointer to that structure.
  57  */
  58 static inline struct mtd_part *mtd_to_part(const struct mtd_info *mtd)
  59 {
  60         return container_of(mtd, struct mtd_part, mtd);
  61 }
  62
  63
  64 /*
  65  * MTD methods which simply translate the effective address and pass through
  66  * to the _real_ device.
  67  */
  68
  69 static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
  70                 size_t *retlen, u_char *buf)
  71 {
  72         struct mtd_part *part = mtd_to_part(mtd);
  73         struct mtd_ecc_stats stats;
  74         int res;
  75
  76         stats = part->parent->ecc_stats;
  77         res = part->parent->_read(part->parent, from + part->offset, len,
  78                                   retlen, buf);
  79         if (unlikely(mtd_is_eccerr(res)))
  80                 mtd->ecc_stats.failed +=
  81                         part->parent->ecc_stats.failed - stats.failed;
  82         else
  83                 mtd->ecc_stats.corrected +=
  84                         part->parent->ecc_stats.corrected - stats.corrected;
  85         return res;
  86 }
  87
  88 static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
  89                 size_t *retlen, void **virt, resource_size_t *phys)
  90 {
  91         struct mtd_part *part = mtd_to_part(mtd);
  92
  93         return part->parent->_point(part->parent, from + part->offset, len,
  94                                     retlen, virt, phys);
  95 }
  96
  97 static int part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
  98 {
  99         struct mtd_part *part = mtd_to_part(mtd);
 100
 101         return part->parent->_unpoint(part->parent, from + part->offset, len);
 102 }
 103
 104 static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
 105                                             unsigned long len,
 106                                             unsigned long offset,
 107                                             unsigned long flags)
 108 {
 109         struct mtd_part *part = mtd_to_part(mtd);
 110
 111         offset += part->offset;
 112         return part->parent->_get_unmapped_area(part->parent, len, offset,
 113                                                 flags);
 114 }
 115
 116 static int part_read_oob(struct mtd_info *mtd, loff_t from,
 117                 struct mtd_oob_ops *ops)
 118 {
 119         struct mtd_part *part = mtd_to_part(mtd);
 120         int res;
 121
 122         if (from >= mtd->size)
 123                 return -EINVAL;
 124         if (ops->datbuf && from + ops->len > mtd->size)
 125                 return -EINVAL;
 126
 127         /*
 128          * If OOB is also requested, make sure that we do not read past the end
 129          * of this partition.
 130          */
 131         if (ops->oobbuf) {
 132                 size_t len, pages;
 133
 134                 len = mtd_oobavail(mtd, ops);
 135                 pages = mtd_div_by_ws(mtd->size, mtd);
 136                 pages -= mtd_div_by_ws(from, mtd);
 137                 if (ops->ooboffs + ops->ooblen > pages * len)
 138                         return -EINVAL;
 139         }
 140
 141         res = part->parent->_read_oob(part->parent, from + part->offset, ops);
 142         if (unlikely(res)) {
 143                 if (mtd_is_bitflip(res))
 144                         mtd->ecc_stats.corrected++;
 145                 if (mtd_is_eccerr(res))
 146                         mtd->ecc_stats.failed++;
 147         }
 148         return res;
 149 }
 150
 151 static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
 152                 size_t len, size_t *retlen, u_char *buf)
 153 {
 154         struct mtd_part *part = mtd_to_part(mtd);
 155         return part->parent->_read_user_prot_reg(part->parent, from, len,
 156                                                  retlen, buf);
 157 }
 158
 159 static int part_get_user_prot_info(struct mtd_info *mtd, size_t len,
 160                                    size_t *retlen, struct otp_info *buf)
 161 {
 162         struct mtd_part *part = mtd_to_part(mtd);
 163         return part->parent->_get_user_prot_info(part->parent, len, retlen,
 164                                                  buf);
 165 }
 166
 167 static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
 168                 size_t len, size_t *retlen, u_char *buf)
 169 {
 170         struct mtd_part *part = mtd_to_part(mtd);
 171         return part->parent->_read_fact_prot_reg(part->parent, from, len,
 172                                                  retlen, buf);
 173 }
 174
 175 static int part_get_fact_prot_info(struct mtd_info *mtd, size_t len,
 176                                    size_t *retlen, struct otp_info *buf)
 177 {
 178         struct mtd_part *part = mtd_to_part(mtd);
 179         return part->parent->_get_fact_prot_info(part->parent, len, retlen,
 180                                                  buf);
 181 }
 182
 183 static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
 184                 size_t *retlen, const u_char *buf)
 185 {
 186         struct mtd_part *part = mtd_to_part(mtd);
 187         return part->parent->_write(part->parent, to + part->offset, len,
 188                                     retlen, buf);
 189 }
 190
 191 static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
 192                 size_t *retlen, const u_char *buf)
 193 {
 194         struct mtd_part *part = mtd_to_part(mtd);
 195         return part->parent->_panic_write(part->parent, to + part->offset, len,
 196                                           retlen, buf);
 197 }
 198
 199 static int part_write_oob(struct mtd_info *mtd, loff_t to,
 200                 struct mtd_oob_ops *ops)
 201 {
 202         struct mtd_part *part = mtd_to_part(mtd);
 203
 204         if (to >= mtd->size)
 205                 return -EINVAL;
 206         if (ops->datbuf && to + ops->len > mtd->size)
 207                 return -EINVAL;
 208         return part->parent->_write_oob(part->parent, to + part->offset, ops);
 209 }
 210
 211 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
 212                 size_t len, size_t *retlen, u_char *buf)
 213 {
 214         struct mtd_part *part = mtd_to_part(mtd);
 215         return part->parent->_write_user_prot_reg(part->parent, from, len,
 216                                                   retlen, buf);
 217 }
 218
 219 static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
 220                 size_t len)
 221 {
 222         struct mtd_part *part = mtd_to_part(mtd);
 223         return part->parent->_lock_user_prot_reg(part->parent, from, len);
 224 }
 225
 226 static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
 227                 unsigned long count, loff_t to, size_t *retlen)
 228 {
 229         struct mtd_part *part = mtd_to_part(mtd);
 230         return part->parent->_writev(part->parent, vecs, count,
 231                                      to + part->offset, retlen);
 232 }
 233
 234 static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
 235 {
 236         struct mtd_part *part = mtd_to_part(mtd);
 237         int ret;
 238
 239         instr->addr += part->offset;
 240         ret = part->parent->_erase(part->parent, instr);
 241         if (ret) {
 242                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 243                         instr->fail_addr -= part->offset;
 244                 instr->addr -= part->offset;
 245         }
 246         return ret;
 247 }
 248
 249 void mtd_erase_callback(struct erase_info *instr)
 250 {
 251         if (instr->mtd->_erase == part_erase) {
 252                 struct mtd_part *part = mtd_to_part(instr->mtd);
 253
 254                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 255                         instr->fail_addr -= part->offset;
 256                 instr->addr -= part->offset;
 257         }
 258         if (instr->callback)
 259                 instr->callback(instr);
 260 }
 261 EXPORT_SYMBOL_GPL(mtd_erase_callback);
 262
 263 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 264 {
 265         struct mtd_part *part = mtd_to_part(mtd);
 266         return part->parent->_lock(part->parent, ofs + part->offset, len);
 267 }
 268
 269 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 270 {
 271         struct mtd_part *part = mtd_to_part(mtd);
 272         return part->parent->_unlock(part->parent, ofs + part->offset, len);
 273 }
 274
 275 static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 276 {
 277         struct mtd_part *part = mtd_to_part(mtd);
 278         return part->parent->_is_locked(part->parent, ofs + part->offset, len);
 279 }
 280
 281 static void part_sync(struct mtd_info *mtd)
 282 {
 283         struct mtd_part *part = mtd_to_part(mtd);
 284         part->parent->_sync(part->parent);
 285 }
 286
 287 static int part_suspend(struct mtd_info *mtd)
 288 {
 289         struct mtd_part *part = mtd_to_part(mtd);
 290         return part->parent->_suspend(part->parent);
 291 }
 292
 293 static void part_resume(struct mtd_info *mtd)
 294 {
 295         struct mtd_part *part = mtd_to_part(mtd);
 296         part->parent->_resume(part->parent);
 297 }
 298
 299 static int part_block_isreserved(struct mtd_info *mtd, loff_t ofs)
 300 {
 301         struct mtd_part *part = mtd_to_part(mtd);
 302         ofs += part->offset;
 303         return part->parent->_block_isreserved(part->parent, ofs);
 304 }
 305
 306 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
 307 {
 308         struct mtd_part *part = mtd_to_part(mtd);
 309         ofs += part->offset;
 310         return part->parent->_block_isbad(part->parent, ofs);
 311 }
 312
 313 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
 314 {
 315         struct mtd_part *part = mtd_to_part(mtd);
 316         int res;
 317
 318         ofs += part->offset;
 319         res = part->parent->_block_markbad(part->parent, ofs);
 320         if (!res)
 321                 mtd->ecc_stats.badblocks++;
 322         return res;
 323 }
 324
 325 static int part_get_device(struct mtd_info *mtd)
 326 {
 327         struct mtd_part *part = mtd_to_part(mtd);
 328         return part->parent->_get_device(part->parent);
 329 }
 330
 331 static void part_put_device(struct mtd_info *mtd)
 332 {
 333         struct mtd_part *part = mtd_to_part(mtd);
 334         part->parent->_put_device(part->parent);
 335 }
 336
 337 static int part_ooblayout_ecc(struct mtd_info *mtd, int section,
 338                               struct mtd_oob_region *oobregion)
 339 {
 340         struct mtd_part *part = mtd_to_part(mtd);
 341
 342         return mtd_ooblayout_ecc(part->parent, section, oobregion);
 343 }
 344
 345 static int part_ooblayout_free(struct mtd_info *mtd, int section,
 346                                struct mtd_oob_region *oobregion)
 347 {
 348         struct mtd_part *part = mtd_to_part(mtd);
 349
 350         return mtd_ooblayout_free(part->parent, section, oobregion);
 351 }
 352
 353 static const struct mtd_ooblayout_ops part_ooblayout_ops = {
 354         .ecc = part_ooblayout_ecc,
 355         .free = part_ooblayout_free,
 356 };
 357
 358 static int part_max_bad_blocks(struct mtd_info *mtd, loff_t ofs, size_t len)
 359 {
 360         struct mtd_part *part = mtd_to_part(mtd);
 361
 362         return part->parent->_max_bad_blocks(part->parent,
 363                                              ofs + part->offset, len);
 364 }
 365
 366 static inline void free_partition(struct mtd_part *p)
 367 {
 368         kfree(p->mtd.name);
 369         kfree(p);
 370 }
 371
 372 /**
 373  * mtd_parse_part - parse MTD partition looking for subpartitions
 374  *
 375  * @slave: part that is supposed to be a container and should be parsed
 376  * @types: NULL-terminated array with names of partition parsers to try
 377  *
 378  * Some partitions are kind of containers with extra subpartitions (volumes).
 379  * There can be various formats of such containers. This function tries to use
 380  * specified parsers to analyze given partition and registers found
 381  * subpartitions on success.
 382  */
 383 static int mtd_parse_part(struct mtd_part *slave, const char *const *types)
 384 {
 385         struct mtd_partitions parsed;
 386         int err;
 387
 388         err = parse_mtd_partitions(&slave->mtd, types, &parsed, NULL);
 389         if (err)
 390                 return err;
 391         else if (!parsed.nr_parts)
 392                 return -ENOENT;
 393
 394         err = add_mtd_partitions(&slave->mtd, parsed.parts, parsed.nr_parts);
 395
 396         mtd_part_parser_cleanup(&parsed);
 397
 398         return err;
 399 }
 400
 401 static struct mtd_part *allocate_partition(struct mtd_info *parent,
 402                         const struct mtd_partition *part, int partno,
 403                         uint64_t cur_offset)
 404 {
 405         int wr_alignment = (parent->flags & MTD_NO_ERASE) ? parent->writesize :
 406                                                             parent->erasesize;
 407         struct mtd_part *slave;
 408         u32 remainder;
 409         char *name;
 410         u64 tmp;
 411
 412         /* allocate the partition structure */
 413         slave = kzalloc(sizeof(*slave), GFP_KERNEL);
 414         name = kstrdup(part->name, GFP_KERNEL);
 415         if (!name || !slave) {
 416                 printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
 417                        parent->name);
 418                 kfree(name);
 419                 kfree(slave);
 420                 return ERR_PTR(-ENOMEM);
 421         }
 422
 423         /* set up the MTD object for this partition */
 424         slave->mtd.type = parent->type;
 425         slave->mtd.flags = parent->flags & ~part->mask_flags;
 426         slave->mtd.size = part->size;
 427         slave->mtd.writesize = parent->writesize;
 428         slave->mtd.writebufsize = parent->writebufsize;
 429         slave->mtd.oobsize = parent->oobsize;
 430         slave->mtd.oobavail = parent->oobavail;
 431         slave->mtd.subpage_sft = parent->subpage_sft;
 432         slave->mtd.pairing = parent->pairing;
 433
 434         slave->mtd.name = name;
 435         slave->mtd.owner = parent->owner;
 436
 437         /* NOTE: Historically, we didn't arrange MTDs as a tree out of
 438          * concern for showing the same data in multiple partitions.
 439          * However, it is very useful to have the master node present,
 440          * so the MTD_PARTITIONED_MASTER option allows that. The master
 441          * will have device nodes etc only if this is set, so make the
 442          * parent conditional on that option. Note, this is a way to
 443          * distinguish between the master and the partition in sysfs.
 444          */
 445         slave->mtd.dev.parent = IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) || mtd_is_partition(parent) ?
 446                                 &parent->dev :
 447                                 parent->dev.parent;
 448         slave->mtd.dev.of_node = part->of_node;
 449
 450         slave->mtd._read = part_read;
 451         slave->mtd._write = part_write;
 452
 453         if (parent->_panic_write)
 454                 slave->mtd._panic_write = part_panic_write;
 455
 456         if (parent->_point && parent->_unpoint) {
 457                 slave->mtd._point = part_point;
 458                 slave->mtd._unpoint = part_unpoint;
 459         }
 460
 461         if (parent->_get_unmapped_area)
 462                 slave->mtd._get_unmapped_area = part_get_unmapped_area;
 463         if (parent->_read_oob)
 464                 slave->mtd._read_oob = part_read_oob;
 465         if (parent->_write_oob)
 466                 slave->mtd._write_oob = part_write_oob;
 467         if (parent->_read_user_prot_reg)
 468                 slave->mtd._read_user_prot_reg = part_read_user_prot_reg;
 469         if (parent->_read_fact_prot_reg)
 470                 slave->mtd._read_fact_prot_reg = part_read_fact_prot_reg;
 471         if (parent->_write_user_prot_reg)
 472                 slave->mtd._write_user_prot_reg = part_write_user_prot_reg;
 473         if (parent->_lock_user_prot_reg)
 474                 slave->mtd._lock_user_prot_reg = part_lock_user_prot_reg;
 475         if (parent->_get_user_prot_info)
 476                 slave->mtd._get_user_prot_info = part_get_user_prot_info;
 477         if (parent->_get_fact_prot_info)
 478                 slave->mtd._get_fact_prot_info = part_get_fact_prot_info;
 479         if (parent->_sync)
 480                 slave->mtd._sync = part_sync;
 481         if (!partno && !parent->dev.class && parent->_suspend &&
 482             parent->_resume) {
 483                 slave->mtd._suspend = part_suspend;
 484                 slave->mtd._resume = part_resume;
 485         }
 486         if (parent->_writev)
 487                 slave->mtd._writev = part_writev;
 488         if (parent->_lock)
 489                 slave->mtd._lock = part_lock;
 490         if (parent->_unlock)
 491                 slave->mtd._unlock = part_unlock;
 492         if (parent->_is_locked)
 493                 slave->mtd._is_locked = part_is_locked;
 494         if (parent->_block_isreserved)
 495                 slave->mtd._block_isreserved = part_block_isreserved;
 496         if (parent->_block_isbad)
 497                 slave->mtd._block_isbad = part_block_isbad;
 498         if (parent->_block_markbad)
 499                 slave->mtd._block_markbad = part_block_markbad;
 500         if (parent->_max_bad_blocks)
 501                 slave->mtd._max_bad_blocks = part_max_bad_blocks;
 502
 503         if (parent->_get_device)
 504                 slave->mtd._get_device = part_get_device;
 505         if (parent->_put_device)
 506                 slave->mtd._put_device = part_put_device;
 507
 508         slave->mtd._erase = part_erase;
 509         slave->parent = parent;
 510         slave->offset = part->offset;
 511
 512         if (slave->offset == MTDPART_OFS_APPEND)
 513                 slave->offset = cur_offset;
 514         if (slave->offset == MTDPART_OFS_NXTBLK) {
 515                 tmp = cur_offset;
 516                 slave->offset = cur_offset;
 517                 remainder = do_div(tmp, wr_alignment);
 518                 if (remainder) {
 519                         slave->offset += wr_alignment - remainder;
 520                         printk(KERN_NOTICE "Moving partition %d: "
 521                                "0x%012llx -> 0x%012llx\n", partno,
 522                                (unsigned long long)cur_offset, (unsigned long long)slave->offset);
 523                 }
 524         }
 525         if (slave->offset == MTDPART_OFS_RETAIN) {
 526                 slave->offset = cur_offset;
 527                 if (parent->size - slave->offset >= slave->mtd.size) {
 528                         slave->mtd.size = parent->size - slave->offset
 529                                                         - slave->mtd.size;
 530                 } else {
 531                         printk(KERN_ERR "mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
 532                                 part->name, parent->size - slave->offset,
 533                                 slave->mtd.size);
 534                         /* register to preserve ordering */
 535                         goto out_register;
 536                 }
 537         }
 538         if (slave->mtd.size == MTDPART_SIZ_FULL)
 539                 slave->mtd.size = parent->size - slave->offset;
 540
 541         printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
 542                 (unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
 543
 544         /* let's do some sanity checks */
 545         if (slave->offset >= parent->size) {
 546                 /* let's register it anyway to preserve ordering */
 547                 slave->offset = 0;
 548                 slave->mtd.size = 0;
 549                 printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
 550                         part->name);
 551                 goto out_register;
 552         }
 553         if (slave->offset + slave->mtd.size > parent->size) {
 554                 slave->mtd.size = parent->size - slave->offset;
 555                 printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
 556                         part->name, parent->name, (unsigned long long)slave->mtd.size);
 557         }
 558         if (parent->numeraseregions > 1) {
 559                 /* Deal with variable erase size stuff */
 560                 int i, max = parent->numeraseregions;
 561                 u64 end = slave->offset + slave->mtd.size;
 562                 struct mtd_erase_region_info *regions = parent->eraseregions;
 563
 564                 /* Find the first erase regions which is part of this
 565                  * partition. */
 566                 for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
 567                         ;
 568                 /* The loop searched for the region _behind_ the first one */
 569                 if (i > 0)
 570                         i--;
 571
 572                 /* Pick biggest erasesize */
 573                 for (; i < max && regions[i].offset < end; i++) {
 574                         if (slave->mtd.erasesize < regions[i].erasesize) {
 575                                 slave->mtd.erasesize = regions[i].erasesize;
 576                         }
 577                 }
 578                 BUG_ON(slave->mtd.erasesize == 0);
 579         } else {
 580                 /* Single erase size */
 581                 slave->mtd.erasesize = parent->erasesize;
 582         }
 583
 584         /*
 585          * Slave erasesize might differ from the master one if the master
 586          * exposes several regions with different erasesize. Adjust
 587          * wr_alignment accordingly.
 588          */
 589         if (!(slave->mtd.flags & MTD_NO_ERASE))
 590                 wr_alignment = slave->mtd.erasesize;
 591
 592         tmp = slave->offset;
 593         remainder = do_div(tmp, wr_alignment);
 594         if ((slave->mtd.flags & MTD_WRITEABLE) && remainder) {
 595                 /* Doesn't start on a boundary of major erase size */
 596                 /* FIXME: Let it be writable if it is on a boundary of
 597                  * _minor_ erase size though */
 598                 slave->mtd.flags &= ~MTD_WRITEABLE;
 599                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase/write block boundary -- force read-only\n",
 600                         part->name);
 601         }
 602
 603         tmp = slave->mtd.size;
 604         remainder = do_div(tmp, wr_alignment);
 605         if ((slave->mtd.flags & MTD_WRITEABLE) && remainder) {
 606                 slave->mtd.flags &= ~MTD_WRITEABLE;
 607                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase/write block -- force read-only\n",
 608                         part->name);
 609         }
 610
 611         mtd_set_ooblayout(&slave->mtd, &part_ooblayout_ops);
 612         slave->mtd.ecc_step_size = parent->ecc_step_size;
 613         slave->mtd.ecc_strength = parent->ecc_strength;
 614         slave->mtd.bitflip_threshold = parent->bitflip_threshold;
 615
 616         if (parent->_block_isbad) {
 617                 uint64_t offs = 0;
 618
 619                 while (offs < slave->mtd.size) {
 620                         if (mtd_block_isreserved(parent, offs + slave->offset))
 621                                 slave->mtd.ecc_stats.bbtblocks++;
 622                         else if (mtd_block_isbad(parent, offs + slave->offset))
 623                                 slave->mtd.ecc_stats.badblocks++;
 624                         offs += slave->mtd.erasesize;
 625                 }
 626         }
 627
 628 out_register:
 629         return slave;
 630 }
 631
 632 static ssize_t mtd_partition_offset_show(struct device *dev,
 633                 struct device_attribute *attr, char *buf)
 634 {
 635         struct mtd_info *mtd = dev_get_drvdata(dev);
 636         struct mtd_part *part = mtd_to_part(mtd);
 637         return snprintf(buf, PAGE_SIZE, "%lld\n", part->offset);
 638 }
 639
 640 static DEVICE_ATTR(offset, S_IRUGO, mtd_partition_offset_show, NULL);
 641
 642 static const struct attribute *mtd_partition_attrs[] = {
 643         &dev_attr_offset.attr,
 644         NULL
 645 };
 646
 647 static int mtd_add_partition_attrs(struct mtd_part *new)
 648 {
 649         int ret = sysfs_create_files(&new->mtd.dev.kobj, mtd_partition_attrs);
 650         if (ret)
 651                 printk(KERN_WARNING
 652                        "mtd: failed to create partition attrs, err=%d\n", ret);
 653         return ret;
 654 }
 655
 656 int mtd_add_partition(struct mtd_info *parent, const char *name,
 657                       long long offset, long long length)
 658 {
 659         struct mtd_partition part;
 660         struct mtd_part *new;
 661         int ret = 0;
 662
 663         /* the direct offset is expected */
 664         if (offset == MTDPART_OFS_APPEND ||
 665             offset == MTDPART_OFS_NXTBLK)
 666                 return -EINVAL;
 667
 668         if (length == MTDPART_SIZ_FULL)
 669                 length = parent->size - offset;
 670
 671         if (length <= 0)
 672                 return -EINVAL;
 673
 674         memset(&part, 0, sizeof(part));
 675         part.name = name;
 676         part.size = length;
 677         part.offset = offset;
 678
 679         new = allocate_partition(parent, &part, -1, offset);
 680         if (IS_ERR(new))
 681                 return PTR_ERR(new);
 682
 683         mutex_lock(&mtd_partitions_mutex);
 684         list_add(&new->list, &mtd_partitions);
 685         mutex_unlock(&mtd_partitions_mutex);
 686
 687         add_mtd_device(&new->mtd);
 688
 689         mtd_add_partition_attrs(new);
 690
 691         return ret;
 692 }
 693 EXPORT_SYMBOL_GPL(mtd_add_partition);
 694
 695 /**
 696  * __mtd_del_partition - delete MTD partition
 697  *
 698  * @priv: internal MTD struct for partition to be deleted
 699  *
 700  * This function must be called with the partitions mutex locked.
 701  */
 702 static int __mtd_del_partition(struct mtd_part *priv)
 703 {
 704         struct mtd_part *child, *next;
 705         int err;
 706
 707         list_for_each_entry_safe(child, next, &mtd_partitions, list) {
 708                 if (child->parent == &priv->mtd) {
 709                         err = __mtd_del_partition(child);
 710                         if (err)
 711                                 return err;
 712                 }
 713         }
 714
 715         sysfs_remove_files(&priv->mtd.dev.kobj, mtd_partition_attrs);
 716
 717         err = del_mtd_device(&priv->mtd);
 718         if (err)
 719                 return err;
 720
 721         list_del(&priv->list);
 722         free_partition(priv);
 723
 724         return 0;
 725 }
 726
 727 /*
 728  * This function unregisters and destroy all slave MTD objects which are
 729  * attached to the given MTD object.
 730  */
 731 int del_mtd_partitions(struct mtd_info *mtd)
 732 {
 733         struct mtd_part *slave, *next;
 734         int ret, err = 0;
 735
 736         mutex_lock(&mtd_partitions_mutex);
 737         list_for_each_entry_safe(slave, next, &mtd_partitions, list)
 738                 if (slave->parent == mtd) {
 739                         ret = __mtd_del_partition(slave);
 740                         if (ret < 0)
 741                                 err = ret;
 742                 }
 743         mutex_unlock(&mtd_partitions_mutex);
 744
 745         return err;
 746 }
 747
 748 int mtd_del_partition(struct mtd_info *mtd, int partno)
 749 {
 750         struct mtd_part *slave, *next;
 751         int ret = -EINVAL;
 752
 753         mutex_lock(&mtd_partitions_mutex);
 754         list_for_each_entry_safe(slave, next, &mtd_partitions, list)
 755                 if ((slave->parent == mtd) &&
 756                     (slave->mtd.index == partno)) {
 757                         ret = __mtd_del_partition(slave);
 758                         break;
 759                 }
 760         mutex_unlock(&mtd_partitions_mutex);
 761
 762         return ret;
 763 }
 764 EXPORT_SYMBOL_GPL(mtd_del_partition);
 765
 766 /*
 767  * This function, given a master MTD object and a partition table, creates
 768  * and registers slave MTD objects which are bound to the master according to
 769  * the partition definitions.
 770  *
 771  * For historical reasons, this function's caller only registers the master
 772  * if the MTD_PARTITIONED_MASTER config option is set.
 773  */
 774
 775 int add_mtd_partitions(struct mtd_info *master,
 776                        const struct mtd_partition *parts,
 777                        int nbparts)
 778 {
 779         struct mtd_part *slave;
 780         uint64_t cur_offset = 0;
 781         int i;
 782
 783         printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
 784
 785         for (i = 0; i < nbparts; i++) {
 786                 slave = allocate_partition(master, parts + i, i, cur_offset);
 787                 if (IS_ERR(slave)) {
 788                         del_mtd_partitions(master);
 789                         return PTR_ERR(slave);
 790                 }
 791
 792                 mutex_lock(&mtd_partitions_mutex);
 793                 list_add(&slave->list, &mtd_partitions);
 794                 mutex_unlock(&mtd_partitions_mutex);
 795
 796                 add_mtd_device(&slave->mtd);
 797                 mtd_add_partition_attrs(slave);
 798                 if (parts[i].types)
 799                         mtd_parse_part(slave, parts[i].types);
 800
 801                 cur_offset = slave->offset + slave->mtd.size;
 802         }
 803
 804         return 0;
 805 }
 806
 807 static DEFINE_SPINLOCK(part_parser_lock);
 808 static LIST_HEAD(part_parsers);
 809
 810 static struct mtd_part_parser *mtd_part_parser_get(const char *name)
 811 {
 812         struct mtd_part_parser *p, *ret = NULL;
 813
 814         spin_lock(&part_parser_lock);
 815
 816         list_for_each_entry(p, &part_parsers, list)
 817                 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
 818                         ret = p;
 819                         break;
 820                 }
 821
 822         spin_unlock(&part_parser_lock);
 823
 824         return ret;
 825 }
 826
 827 static inline void mtd_part_parser_put(const struct mtd_part_parser *p)
 828 {
 829         module_put(p->owner);
 830 }
 831
 832 /*
 833  * Many partition parsers just expected the core to kfree() all their data in
 834  * one chunk. Do that by default.
 835  */
 836 static void mtd_part_parser_cleanup_default(const struct mtd_partition *pparts,
 837                                             int nr_parts)
 838 {
 839         kfree(pparts);
 840 }
 841
 842 int __register_mtd_parser(struct mtd_part_parser *p, struct module *owner)
 843 {
 844         p->owner = owner;
 845
 846         if (!p->cleanup)
 847                 p->cleanup = &mtd_part_parser_cleanup_default;
 848
 849         spin_lock(&part_parser_lock);
 850         list_add(&p->list, &part_parsers);
 851         spin_unlock(&part_parser_lock);
 852
 853         return 0;
 854 }
 855 EXPORT_SYMBOL_GPL(__register_mtd_parser);
 856
 857 void deregister_mtd_parser(struct mtd_part_parser *p)
 858 {
 859         spin_lock(&part_parser_lock);
 860         list_del(&p->list);
 861         spin_unlock(&part_parser_lock);
 862 }
 863 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
 864
 865 /*
 866  * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
 867  * are changing this array!
 868  */
 869 static const char * const default_mtd_part_types[] = {
 870         "cmdlinepart",
 871         "ofpart",
 872         NULL
 873 };
 874
 875 static int mtd_part_do_parse(struct mtd_part_parser *parser,
 876                              struct mtd_info *master,
 877                              struct mtd_partitions *pparts,
 878                              struct mtd_part_parser_data *data)
 879 {
 880         int ret;
 881
 882         ret = (*parser->parse_fn)(master, &pparts->parts, data);
 883         pr_debug("%s: parser %s: %i\n", master->name, parser->name, ret);
 884         if (ret <= 0)
 885                 return ret;
 886
 887         pr_notice("%d %s partitions found on MTD device %s\n", ret,
 888                   parser->name, master->name);
 889
 890         pparts->nr_parts = ret;
 891         pparts->parser = parser;
 892
 893         return ret;
 894 }
 895
 896 /**
 897  * parse_mtd_partitions - parse MTD partitions
 898  * @master: the master partition (describes whole MTD device)
 899  * @types: names of partition parsers to try or %NULL
 900  * @pparts: info about partitions found is returned here
 901  * @data: MTD partition parser-specific data
 902  *
 903  * This function tries to find partition on MTD device @master. It uses MTD
 904  * partition parsers, specified in @types. However, if @types is %NULL, then
 905  * the default list of parsers is used. The default list contains only the
 906  * "cmdlinepart" and "ofpart" parsers ATM.
 907  * Note: If there are more then one parser in @types, the kernel only takes the
 908  * partitions parsed out by the first parser.
 909  *
 910  * This function may return:
 911  * o a negative error code in case of failure
 912  * o zero otherwise, and @pparts will describe the partitions, number of
 913  *   partitions, and the parser which parsed them. Caller must release
 914  *   resources with mtd_part_parser_cleanup() when finished with the returned
 915  *   data.
 916  */
 917 int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
 918                          struct mtd_partitions *pparts,
 919                          struct mtd_part_parser_data *data)
 920 {
 921         struct mtd_part_parser *parser;
 922         int ret, err = 0;
 923
 924         if (!types)
 925                 types = default_mtd_part_types;
 926
 927         for ( ; *types; types++) {
 928                 pr_debug("%s: parsing partitions %s\n", master->name, *types);
 929                 parser = mtd_part_parser_get(*types);
 930                 if (!parser && !request_module("%s", *types))
 931                         parser = mtd_part_parser_get(*types);
 932                 pr_debug("%s: got parser %s\n", master->name,
 933                          parser ? parser->name : NULL);
 934                 if (!parser)
 935                         continue;
 936                 ret = mtd_part_do_parse(parser, master, pparts, data);
 937                 /* Found partitions! */
 938                 if (ret > 0)
 939                         return 0;
 940                 mtd_part_parser_put(parser);
 941                 /*
 942                  * Stash the first error we see; only report it if no parser
 943                  * succeeds
 944                  */
 945                 if (ret < 0 && !err)
 946                         err = ret;
 947         }
 948         return err;
 949 }
 950
 951 void mtd_part_parser_cleanup(struct mtd_partitions *parts)
 952 {
 953         const struct mtd_part_parser *parser;
 954
 955         if (!parts)
 956                 return;
 957
 958         parser = parts->parser;
 959         if (parser) {
 960                 if (parser->cleanup)
 961                         parser->cleanup(parts->parts, parts->nr_parts);
 962
 963                 mtd_part_parser_put(parser);
 964         }
 965 }
 966
 967 int mtd_is_partition(const struct mtd_info *mtd)
 968 {
 969         struct mtd_part *part;
 970         int ispart = 0;
 971
 972         mutex_lock(&mtd_partitions_mutex);
 973         list_for_each_entry(part, &mtd_partitions, list)
 974                 if (&part->mtd == mtd) {
 975                         ispart = 1;
 976                         break;
 977                 }
 978         mutex_unlock(&mtd_partitions_mutex);
 979
 980         return ispart;
 981 }
 982 EXPORT_SYMBOL_GPL(mtd_is_partition);
 983
 984 /* Returns the size of the entire flash chip */
 985 uint64_t mtd_get_device_size(const struct mtd_info *mtd)
 986 {
 987         if (!mtd_is_partition(mtd))
 988                 return mtd->size;
 989
 990         return mtd_get_device_size(mtd_to_part(mtd)->parent);
 991 }
 992 EXPORT_SYMBOL_GPL(mtd_get_device_size);