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 inline void free_partition(struct mtd_part *p)
 353 {
 354         kfree(p->mtd.name);
 355         kfree(p);
 356 }
 357
 358 /*
 359  * This function unregisters and destroy all slave MTD objects which are
 360  * attached to the given master MTD object.
 361  */
 362
 363 int del_mtd_partitions(struct mtd_info *master)
 364 {
 365         struct mtd_part *slave, *next;
 366         int ret, err = 0;
 367
 368         mutex_lock(&mtd_partitions_mutex);
 369         list_for_each_entry_safe(slave, next, &mtd_partitions, list)
 370                 if (slave->master == master) {
 371                         ret = del_mtd_device(&slave->mtd);
 372                         if (ret < 0) {
 373                                 err = ret;
 374                                 continue;
 375                         }
 376                         list_del(&slave->list);
 377                         free_partition(slave);
 378                 }
 379         mutex_unlock(&mtd_partitions_mutex);
 380
 381         return err;
 382 }
 383
 384 static struct mtd_part *allocate_partition(struct mtd_info *master,
 385                         const struct mtd_partition *part, int partno,
 386                         uint64_t cur_offset)
 387 {
 388         struct mtd_part *slave;
 389         char *name;
 390
 391         /* allocate the partition structure */
 392         slave = kzalloc(sizeof(*slave), GFP_KERNEL);
 393         name = kstrdup(part->name, GFP_KERNEL);
 394         if (!name || !slave) {
 395                 printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
 396                        master->name);
 397                 kfree(name);
 398                 kfree(slave);
 399                 return ERR_PTR(-ENOMEM);
 400         }
 401
 402         /* set up the MTD object for this partition */
 403         slave->mtd.type = master->type;
 404         slave->mtd.flags = master->flags & ~part->mask_flags;
 405         slave->mtd.size = part->size;
 406         slave->mtd.writesize = master->writesize;
 407         slave->mtd.writebufsize = master->writebufsize;
 408         slave->mtd.oobsize = master->oobsize;
 409         slave->mtd.oobavail = master->oobavail;
 410         slave->mtd.subpage_sft = master->subpage_sft;
 411         slave->mtd.pairing = master->pairing;
 412
 413         slave->mtd.name = name;
 414         slave->mtd.owner = master->owner;
 415
 416         /* NOTE: Historically, we didn't arrange MTDs as a tree out of
 417          * concern for showing the same data in multiple partitions.
 418          * However, it is very useful to have the master node present,
 419          * so the MTD_PARTITIONED_MASTER option allows that. The master
 420          * will have device nodes etc only if this is set, so make the
 421          * parent conditional on that option. Note, this is a way to
 422          * distinguish between the master and the partition in sysfs.
 423          */
 424         slave->mtd.dev.parent = IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) ?
 425                                 &master->dev :
 426                                 master->dev.parent;
 427
 428         slave->mtd._read = part_read;
 429         slave->mtd._write = part_write;
 430
 431         if (master->_panic_write)
 432                 slave->mtd._panic_write = part_panic_write;
 433
 434         if (master->_point && master->_unpoint) {
 435                 slave->mtd._point = part_point;
 436                 slave->mtd._unpoint = part_unpoint;
 437         }
 438
 439         if (master->_get_unmapped_area)
 440                 slave->mtd._get_unmapped_area = part_get_unmapped_area;
 441         if (master->_read_oob)
 442                 slave->mtd._read_oob = part_read_oob;
 443         if (master->_write_oob)
 444                 slave->mtd._write_oob = part_write_oob;
 445         if (master->_read_user_prot_reg)
 446                 slave->mtd._read_user_prot_reg = part_read_user_prot_reg;
 447         if (master->_read_fact_prot_reg)
 448                 slave->mtd._read_fact_prot_reg = part_read_fact_prot_reg;
 449         if (master->_write_user_prot_reg)
 450                 slave->mtd._write_user_prot_reg = part_write_user_prot_reg;
 451         if (master->_lock_user_prot_reg)
 452                 slave->mtd._lock_user_prot_reg = part_lock_user_prot_reg;
 453         if (master->_get_user_prot_info)
 454                 slave->mtd._get_user_prot_info = part_get_user_prot_info;
 455         if (master->_get_fact_prot_info)
 456                 slave->mtd._get_fact_prot_info = part_get_fact_prot_info;
 457         if (master->_sync)
 458                 slave->mtd._sync = part_sync;
 459         if (!partno && !master->dev.class && master->_suspend &&
 460             master->_resume) {
 461                         slave->mtd._suspend = part_suspend;
 462                         slave->mtd._resume = part_resume;
 463         }
 464         if (master->_writev)
 465                 slave->mtd._writev = part_writev;
 466         if (master->_lock)
 467                 slave->mtd._lock = part_lock;
 468         if (master->_unlock)
 469                 slave->mtd._unlock = part_unlock;
 470         if (master->_is_locked)
 471                 slave->mtd._is_locked = part_is_locked;
 472         if (master->_block_isreserved)
 473                 slave->mtd._block_isreserved = part_block_isreserved;
 474         if (master->_block_isbad)
 475                 slave->mtd._block_isbad = part_block_isbad;
 476         if (master->_block_markbad)
 477                 slave->mtd._block_markbad = part_block_markbad;
 478
 479         if (master->_get_device)
 480                 slave->mtd._get_device = part_get_device;
 481         if (master->_put_device)
 482                 slave->mtd._put_device = part_put_device;
 483
 484         slave->mtd._erase = part_erase;
 485         slave->master = master;
 486         slave->offset = part->offset;
 487
 488         if (slave->offset == MTDPART_OFS_APPEND)
 489                 slave->offset = cur_offset;
 490         if (slave->offset == MTDPART_OFS_NXTBLK) {
 491                 slave->offset = cur_offset;
 492                 if (mtd_mod_by_eb(cur_offset, master) != 0) {
 493                         /* Round up to next erasesize */
 494                         slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
 495                         printk(KERN_NOTICE "Moving partition %d: "
 496                                "0x%012llx -> 0x%012llx\n", partno,
 497                                (unsigned long long)cur_offset, (unsigned long long)slave->offset);
 498                 }
 499         }
 500         if (slave->offset == MTDPART_OFS_RETAIN) {
 501                 slave->offset = cur_offset;
 502                 if (master->size - slave->offset >= slave->mtd.size) {
 503                         slave->mtd.size = master->size - slave->offset
 504                                                         - slave->mtd.size;
 505                 } else {
 506                         printk(KERN_ERR "mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
 507                                 part->name, master->size - slave->offset,
 508                                 slave->mtd.size);
 509                         /* register to preserve ordering */
 510                         goto out_register;
 511                 }
 512         }
 513         if (slave->mtd.size == MTDPART_SIZ_FULL)
 514                 slave->mtd.size = master->size - slave->offset;
 515
 516         printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
 517                 (unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
 518
 519         /* let's do some sanity checks */
 520         if (slave->offset >= master->size) {
 521                 /* let's register it anyway to preserve ordering */
 522                 slave->offset = 0;
 523                 slave->mtd.size = 0;
 524                 printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
 525                         part->name);
 526                 goto out_register;
 527         }
 528         if (slave->offset + slave->mtd.size > master->size) {
 529                 slave->mtd.size = master->size - slave->offset;
 530                 printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
 531                         part->name, master->name, (unsigned long long)slave->mtd.size);
 532         }
 533         if (master->numeraseregions > 1) {
 534                 /* Deal with variable erase size stuff */
 535                 int i, max = master->numeraseregions;
 536                 u64 end = slave->offset + slave->mtd.size;
 537                 struct mtd_erase_region_info *regions = master->eraseregions;
 538
 539                 /* Find the first erase regions which is part of this
 540                  * partition. */
 541                 for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
 542                         ;
 543                 /* The loop searched for the region _behind_ the first one */
 544                 if (i > 0)
 545                         i--;
 546
 547                 /* Pick biggest erasesize */
 548                 for (; i < max && regions[i].offset < end; i++) {
 549                         if (slave->mtd.erasesize < regions[i].erasesize) {
 550                                 slave->mtd.erasesize = regions[i].erasesize;
 551                         }
 552                 }
 553                 BUG_ON(slave->mtd.erasesize == 0);
 554         } else {
 555                 /* Single erase size */
 556                 slave->mtd.erasesize = master->erasesize;
 557         }
 558
 559         if ((slave->mtd.flags & MTD_WRITEABLE) &&
 560             mtd_mod_by_eb(slave->offset, &slave->mtd)) {
 561                 /* Doesn't start on a boundary of major erase size */
 562                 /* FIXME: Let it be writable if it is on a boundary of
 563                  * _minor_ erase size though */
 564                 slave->mtd.flags &= ~MTD_WRITEABLE;
 565                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
 566                         part->name);
 567         }
 568         if ((slave->mtd.flags & MTD_WRITEABLE) &&
 569             mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
 570                 slave->mtd.flags &= ~MTD_WRITEABLE;
 571                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
 572                         part->name);
 573         }
 574
 575         mtd_set_ooblayout(&slave->mtd, &part_ooblayout_ops);
 576         slave->mtd.ecc_step_size = master->ecc_step_size;
 577         slave->mtd.ecc_strength = master->ecc_strength;
 578         slave->mtd.bitflip_threshold = master->bitflip_threshold;
 579
 580         if (master->_block_isbad) {
 581                 uint64_t offs = 0;
 582
 583                 while (offs < slave->mtd.size) {
 584                         if (mtd_block_isreserved(master, offs + slave->offset))
 585                                 slave->mtd.ecc_stats.bbtblocks++;
 586                         else if (mtd_block_isbad(master, offs + slave->offset))
 587                                 slave->mtd.ecc_stats.badblocks++;
 588                         offs += slave->mtd.erasesize;
 589                 }
 590         }
 591
 592 out_register:
 593         return slave;
 594 }
 595
 596 static ssize_t mtd_partition_offset_show(struct device *dev,
 597                 struct device_attribute *attr, char *buf)
 598 {
 599         struct mtd_info *mtd = dev_get_drvdata(dev);
 600         struct mtd_part *part = mtd_to_part(mtd);
 601         return snprintf(buf, PAGE_SIZE, "%lld\n", part->offset);
 602 }
 603
 604 static DEVICE_ATTR(offset, S_IRUGO, mtd_partition_offset_show, NULL);
 605
 606 static const struct attribute *mtd_partition_attrs[] = {
 607         &dev_attr_offset.attr,
 608         NULL
 609 };
 610
 611 static int mtd_add_partition_attrs(struct mtd_part *new)
 612 {
 613         int ret = sysfs_create_files(&new->mtd.dev.kobj, mtd_partition_attrs);
 614         if (ret)
 615                 printk(KERN_WARNING
 616                        "mtd: failed to create partition attrs, err=%d\n", ret);
 617         return ret;
 618 }
 619
 620 int mtd_add_partition(struct mtd_info *master, const char *name,
 621                       long long offset, long long length)
 622 {
 623         struct mtd_partition part;
 624         struct mtd_part *new;
 625         int ret = 0;
 626
 627         /* the direct offset is expected */
 628         if (offset == MTDPART_OFS_APPEND ||
 629             offset == MTDPART_OFS_NXTBLK)
 630                 return -EINVAL;
 631
 632         if (length == MTDPART_SIZ_FULL)
 633                 length = master->size - offset;
 634
 635         if (length <= 0)
 636                 return -EINVAL;
 637
 638         memset(&part, 0, sizeof(part));
 639         part.name = name;
 640         part.size = length;
 641         part.offset = offset;
 642
 643         new = allocate_partition(master, &part, -1, offset);
 644         if (IS_ERR(new))
 645                 return PTR_ERR(new);
 646
 647         mutex_lock(&mtd_partitions_mutex);
 648         list_add(&new->list, &mtd_partitions);
 649         mutex_unlock(&mtd_partitions_mutex);
 650
 651         add_mtd_device(&new->mtd);
 652
 653         mtd_add_partition_attrs(new);
 654
 655         return ret;
 656 }
 657 EXPORT_SYMBOL_GPL(mtd_add_partition);
 658
 659 int mtd_del_partition(struct mtd_info *master, int partno)
 660 {
 661         struct mtd_part *slave, *next;
 662         int ret = -EINVAL;
 663
 664         mutex_lock(&mtd_partitions_mutex);
 665         list_for_each_entry_safe(slave, next, &mtd_partitions, list)
 666                 if ((slave->master == master) &&
 667                     (slave->mtd.index == partno)) {
 668                         sysfs_remove_files(&slave->mtd.dev.kobj,
 669                                            mtd_partition_attrs);
 670                         ret = del_mtd_device(&slave->mtd);
 671                         if (ret < 0)
 672                                 break;
 673
 674                         list_del(&slave->list);
 675                         free_partition(slave);
 676                         break;
 677                 }
 678         mutex_unlock(&mtd_partitions_mutex);
 679
 680         return ret;
 681 }
 682 EXPORT_SYMBOL_GPL(mtd_del_partition);
 683
 684 /*
 685  * This function, given a master MTD object and a partition table, creates
 686  * and registers slave MTD objects which are bound to the master according to
 687  * the partition definitions.
 688  *
 689  * For historical reasons, this function's caller only registers the master
 690  * if the MTD_PARTITIONED_MASTER config option is set.
 691  */
 692
 693 int add_mtd_partitions(struct mtd_info *master,
 694                        const struct mtd_partition *parts,
 695                        int nbparts)
 696 {
 697         struct mtd_part *slave;
 698         uint64_t cur_offset = 0;
 699         int i;
 700
 701         printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
 702
 703         for (i = 0; i < nbparts; i++) {
 704                 slave = allocate_partition(master, parts + i, i, cur_offset);
 705                 if (IS_ERR(slave)) {
 706                         del_mtd_partitions(master);
 707                         return PTR_ERR(slave);
 708                 }
 709
 710                 mutex_lock(&mtd_partitions_mutex);
 711                 list_add(&slave->list, &mtd_partitions);
 712                 mutex_unlock(&mtd_partitions_mutex);
 713
 714                 add_mtd_device(&slave->mtd);
 715                 mtd_add_partition_attrs(slave);
 716
 717                 cur_offset = slave->offset + slave->mtd.size;
 718         }
 719
 720         return 0;
 721 }
 722
 723 static DEFINE_SPINLOCK(part_parser_lock);
 724 static LIST_HEAD(part_parsers);
 725
 726 static struct mtd_part_parser *mtd_part_parser_get(const char *name)
 727 {
 728         struct mtd_part_parser *p, *ret = NULL;
 729
 730         spin_lock(&part_parser_lock);
 731
 732         list_for_each_entry(p, &part_parsers, list)
 733                 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
 734                         ret = p;
 735                         break;
 736                 }
 737
 738         spin_unlock(&part_parser_lock);
 739
 740         return ret;
 741 }
 742
 743 static inline void mtd_part_parser_put(const struct mtd_part_parser *p)
 744 {
 745         module_put(p->owner);
 746 }
 747
 748 /*
 749  * Many partition parsers just expected the core to kfree() all their data in
 750  * one chunk. Do that by default.
 751  */
 752 static void mtd_part_parser_cleanup_default(const struct mtd_partition *pparts,
 753                                             int nr_parts)
 754 {
 755         kfree(pparts);
 756 }
 757
 758 int __register_mtd_parser(struct mtd_part_parser *p, struct module *owner)
 759 {
 760         p->owner = owner;
 761
 762         if (!p->cleanup)
 763                 p->cleanup = &mtd_part_parser_cleanup_default;
 764
 765         spin_lock(&part_parser_lock);
 766         list_add(&p->list, &part_parsers);
 767         spin_unlock(&part_parser_lock);
 768
 769         return 0;
 770 }
 771 EXPORT_SYMBOL_GPL(__register_mtd_parser);
 772
 773 void deregister_mtd_parser(struct mtd_part_parser *p)
 774 {
 775         spin_lock(&part_parser_lock);
 776         list_del(&p->list);
 777         spin_unlock(&part_parser_lock);
 778 }
 779 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
 780
 781 /*
 782  * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
 783  * are changing this array!
 784  */
 785 static const char * const default_mtd_part_types[] = {
 786         "cmdlinepart",
 787         "ofpart",
 788         NULL
 789 };
 790
 791 /**
 792  * parse_mtd_partitions - parse MTD partitions
 793  * @master: the master partition (describes whole MTD device)
 794  * @types: names of partition parsers to try or %NULL
 795  * @pparts: info about partitions found is returned here
 796  * @data: MTD partition parser-specific data
 797  *
 798  * This function tries to find partition on MTD device @master. It uses MTD
 799  * partition parsers, specified in @types. However, if @types is %NULL, then
 800  * the default list of parsers is used. The default list contains only the
 801  * "cmdlinepart" and "ofpart" parsers ATM.
 802  * Note: If there are more then one parser in @types, the kernel only takes the
 803  * partitions parsed out by the first parser.
 804  *
 805  * This function may return:
 806  * o a negative error code in case of failure
 807  * o zero otherwise, and @pparts will describe the partitions, number of
 808  *   partitions, and the parser which parsed them. Caller must release
 809  *   resources with mtd_part_parser_cleanup() when finished with the returned
 810  *   data.
 811  */
 812 int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
 813                          struct mtd_partitions *pparts,
 814                          struct mtd_part_parser_data *data)
 815 {
 816         struct mtd_part_parser *parser;
 817         int ret, err = 0;
 818
 819         if (!types)
 820                 types = default_mtd_part_types;
 821
 822         for ( ; *types; types++) {
 823                 pr_debug("%s: parsing partitions %s\n", master->name, *types);
 824                 parser = mtd_part_parser_get(*types);
 825                 if (!parser && !request_module("%s", *types))
 826                         parser = mtd_part_parser_get(*types);
 827                 pr_debug("%s: got parser %s\n", master->name,
 828                          parser ? parser->name : NULL);
 829                 if (!parser)
 830                         continue;
 831                 ret = (*parser->parse_fn)(master, &pparts->parts, data);
 832                 pr_debug("%s: parser %s: %i\n",
 833                          master->name, parser->name, ret);
 834                 if (ret > 0) {
 835                         printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
 836                                ret, parser->name, master->name);
 837                         pparts->nr_parts = ret;
 838                         pparts->parser = parser;
 839                         return 0;
 840                 }
 841                 mtd_part_parser_put(parser);
 842                 /*
 843                  * Stash the first error we see; only report it if no parser
 844                  * succeeds
 845                  */
 846                 if (ret < 0 && !err)
 847                         err = ret;
 848         }
 849         return err;
 850 }
 851
 852 void mtd_part_parser_cleanup(struct mtd_partitions *parts)
 853 {
 854         const struct mtd_part_parser *parser;
 855
 856         if (!parts)
 857                 return;
 858
 859         parser = parts->parser;
 860         if (parser) {
 861                 if (parser->cleanup)
 862                         parser->cleanup(parts->parts, parts->nr_parts);
 863
 864                 mtd_part_parser_put(parser);
 865         }
 866 }
 867
 868 int mtd_is_partition(const struct mtd_info *mtd)
 869 {
 870         struct mtd_part *part;
 871         int ispart = 0;
 872
 873         mutex_lock(&mtd_partitions_mutex);
 874         list_for_each_entry(part, &mtd_partitions, list)
 875                 if (&part->mtd == mtd) {
 876                         ispart = 1;
 877                         break;
 878                 }
 879         mutex_unlock(&mtd_partitions_mutex);
 880
 881         return ispart;
 882 }
 883 EXPORT_SYMBOL_GPL(mtd_is_partition);
 884
 885 /* Returns the size of the entire flash chip */
 886 uint64_t mtd_get_device_size(const struct mtd_info *mtd)
 887 {
 888         if (!mtd_is_partition(mtd))
 889                 return mtd->size;
 890
 891         return mtd_to_part(mtd)->master->size;
 892 }
 893 EXPORT_SYMBOL_GPL(mtd_get_device_size);