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