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