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