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 with this macro. 51 */ 52 #define PART(x) ((struct mtd_part *)(x)) 53 54 55 /* 56 * MTD methods which simply translate the effective address and pass through 57 * to the _real_ device. 58 */ 59 60 static int part_read(struct mtd_info *mtd, loff_t from, size_t len, 61 size_t *retlen, u_char *buf) 62 { 63 struct mtd_part *part = PART(mtd); 64 struct mtd_ecc_stats stats; 65 int res; 66 67 stats = part->master->ecc_stats; 68 69 if (from >= mtd->size) 70 len = 0; 71 else if (from + len > mtd->size) 72 len = mtd->size - from; 73 res = mtd_read(part->master, from + part->offset, len, retlen, buf); 74 if (unlikely(res)) { 75 if (mtd_is_bitflip(res)) 76 mtd->ecc_stats.corrected += part->master->ecc_stats.corrected - stats.corrected; 77 if (mtd_is_eccerr(res)) 78 mtd->ecc_stats.failed += part->master->ecc_stats.failed - stats.failed; 79 } 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 = PART(mtd); 87 if (from >= mtd->size) 88 len = 0; 89 else if (from + len > mtd->size) 90 len = mtd->size - from; 91 return mtd_point(part->master, from + part->offset, len, retlen, 92 virt, phys); 93 } 94 95 static void part_unpoint(struct mtd_info *mtd, loff_t from, size_t len) 96 { 97 struct mtd_part *part = PART(mtd); 98 99 mtd_unpoint(part->master, from + part->offset, len); 100 } 101 102 static unsigned long part_get_unmapped_area(struct mtd_info *mtd, 103 unsigned long len, 104 unsigned long offset, 105 unsigned long flags) 106 { 107 struct mtd_part *part = PART(mtd); 108 109 offset += part->offset; 110 return mtd_get_unmapped_area(part->master, len, offset, flags); 111 } 112 113 static int part_read_oob(struct mtd_info *mtd, loff_t from, 114 struct mtd_oob_ops *ops) 115 { 116 struct mtd_part *part = PART(mtd); 117 int res; 118 119 if (from >= mtd->size) 120 return -EINVAL; 121 if (ops->datbuf && from + ops->len > mtd->size) 122 return -EINVAL; 123 124 /* 125 * If OOB is also requested, make sure that we do not read past the end 126 * of this partition. 127 */ 128 if (ops->oobbuf) { 129 size_t len, pages; 130 131 if (ops->mode == MTD_OPS_AUTO_OOB) 132 len = mtd->oobavail; 133 else 134 len = mtd->oobsize; 135 pages = mtd_div_by_ws(mtd->size, mtd); 136 pages -= mtd_div_by_ws(from, mtd); 137 if (ops->ooboffs + ops->ooblen > pages * len) 138 return -EINVAL; 139 } 140 141 res = mtd_read_oob(part->master, from + part->offset, ops); 142 if (unlikely(res)) { 143 if (mtd_is_bitflip(res)) 144 mtd->ecc_stats.corrected++; 145 if (mtd_is_eccerr(res)) 146 mtd->ecc_stats.failed++; 147 } 148 return res; 149 } 150 151 static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from, 152 size_t len, size_t *retlen, u_char *buf) 153 { 154 struct mtd_part *part = PART(mtd); 155 return mtd_read_user_prot_reg(part->master, from, len, retlen, buf); 156 } 157 158 static int part_get_user_prot_info(struct mtd_info *mtd, 159 struct otp_info *buf, size_t len) 160 { 161 struct mtd_part *part = PART(mtd); 162 return mtd_get_user_prot_info(part->master, buf, len); 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 = PART(mtd); 169 return mtd_read_fact_prot_reg(part->master, from, len, retlen, buf); 170 } 171 172 static int part_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf, 173 size_t len) 174 { 175 struct mtd_part *part = PART(mtd); 176 return mtd_get_fact_prot_info(part->master, buf, len); 177 } 178 179 static int part_write(struct mtd_info *mtd, loff_t to, size_t len, 180 size_t *retlen, const u_char *buf) 181 { 182 struct mtd_part *part = PART(mtd); 183 if (!(mtd->flags & MTD_WRITEABLE)) 184 return -EROFS; 185 if (to >= mtd->size) 186 len = 0; 187 else if (to + len > mtd->size) 188 len = mtd->size - to; 189 return mtd_write(part->master, to + part->offset, len, retlen, buf); 190 } 191 192 static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len, 193 size_t *retlen, const u_char *buf) 194 { 195 struct mtd_part *part = PART(mtd); 196 if (!(mtd->flags & MTD_WRITEABLE)) 197 return -EROFS; 198 if (to >= mtd->size) 199 len = 0; 200 else if (to + len > mtd->size) 201 len = mtd->size - to; 202 return mtd_panic_write(part->master, to + part->offset, len, retlen, 203 buf); 204 } 205 206 static int part_write_oob(struct mtd_info *mtd, loff_t to, 207 struct mtd_oob_ops *ops) 208 { 209 struct mtd_part *part = PART(mtd); 210 211 if (!(mtd->flags & MTD_WRITEABLE)) 212 return -EROFS; 213 214 if (to >= mtd->size) 215 return -EINVAL; 216 if (ops->datbuf && to + ops->len > mtd->size) 217 return -EINVAL; 218 return mtd_write_oob(part->master, to + part->offset, ops); 219 } 220 221 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from, 222 size_t len, size_t *retlen, u_char *buf) 223 { 224 struct mtd_part *part = PART(mtd); 225 return mtd_write_user_prot_reg(part->master, from, len, retlen, buf); 226 } 227 228 static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, 229 size_t len) 230 { 231 struct mtd_part *part = PART(mtd); 232 return mtd_lock_user_prot_reg(part->master, from, len); 233 } 234 235 static int part_writev(struct mtd_info *mtd, const struct kvec *vecs, 236 unsigned long count, loff_t to, size_t *retlen) 237 { 238 struct mtd_part *part = PART(mtd); 239 if (!(mtd->flags & MTD_WRITEABLE)) 240 return -EROFS; 241 return mtd_writev(part->master, vecs, count, to + part->offset, 242 retlen); 243 } 244 245 static int part_erase(struct mtd_info *mtd, struct erase_info *instr) 246 { 247 struct mtd_part *part = PART(mtd); 248 int ret; 249 if (!(mtd->flags & MTD_WRITEABLE)) 250 return -EROFS; 251 if (instr->addr >= mtd->size) 252 return -EINVAL; 253 instr->addr += part->offset; 254 ret = mtd_erase(part->master, instr); 255 if (ret) { 256 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN) 257 instr->fail_addr -= part->offset; 258 instr->addr -= part->offset; 259 } 260 return ret; 261 } 262 263 void mtd_erase_callback(struct erase_info *instr) 264 { 265 if (instr->mtd->erase == part_erase) { 266 struct mtd_part *part = PART(instr->mtd); 267 268 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN) 269 instr->fail_addr -= part->offset; 270 instr->addr -= part->offset; 271 } 272 if (instr->callback) 273 instr->callback(instr); 274 } 275 EXPORT_SYMBOL_GPL(mtd_erase_callback); 276 277 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len) 278 { 279 struct mtd_part *part = PART(mtd); 280 if ((len + ofs) > mtd->size) 281 return -EINVAL; 282 return mtd_lock(part->master, ofs + part->offset, len); 283 } 284 285 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len) 286 { 287 struct mtd_part *part = PART(mtd); 288 if ((len + ofs) > mtd->size) 289 return -EINVAL; 290 return mtd_unlock(part->master, ofs + part->offset, len); 291 } 292 293 static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len) 294 { 295 struct mtd_part *part = PART(mtd); 296 if ((len + ofs) > mtd->size) 297 return -EINVAL; 298 return mtd_is_locked(part->master, ofs + part->offset, len); 299 } 300 301 static void part_sync(struct mtd_info *mtd) 302 { 303 struct mtd_part *part = PART(mtd); 304 mtd_sync(part->master); 305 } 306 307 static int part_suspend(struct mtd_info *mtd) 308 { 309 struct mtd_part *part = PART(mtd); 310 return mtd_suspend(part->master); 311 } 312 313 static void part_resume(struct mtd_info *mtd) 314 { 315 struct mtd_part *part = PART(mtd); 316 mtd_resume(part->master); 317 } 318 319 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs) 320 { 321 struct mtd_part *part = PART(mtd); 322 if (ofs >= mtd->size) 323 return -EINVAL; 324 ofs += part->offset; 325 return mtd_block_isbad(part->master, ofs); 326 } 327 328 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs) 329 { 330 struct mtd_part *part = PART(mtd); 331 int res; 332 333 if (!(mtd->flags & MTD_WRITEABLE)) 334 return -EROFS; 335 if (ofs >= mtd->size) 336 return -EINVAL; 337 ofs += part->offset; 338 res = mtd_block_markbad(part->master, ofs); 339 if (!res) 340 mtd->ecc_stats.badblocks++; 341 return res; 342 } 343 344 static inline void free_partition(struct mtd_part *p) 345 { 346 kfree(p->mtd.name); 347 kfree(p); 348 } 349 350 /* 351 * This function unregisters and destroy all slave MTD objects which are 352 * attached to the given master MTD object. 353 */ 354 355 int del_mtd_partitions(struct mtd_info *master) 356 { 357 struct mtd_part *slave, *next; 358 int ret, err = 0; 359 360 mutex_lock(&mtd_partitions_mutex); 361 list_for_each_entry_safe(slave, next, &mtd_partitions, list) 362 if (slave->master == master) { 363 ret = del_mtd_device(&slave->mtd); 364 if (ret < 0) { 365 err = ret; 366 continue; 367 } 368 list_del(&slave->list); 369 free_partition(slave); 370 } 371 mutex_unlock(&mtd_partitions_mutex); 372 373 return err; 374 } 375 376 static struct mtd_part *allocate_partition(struct mtd_info *master, 377 const struct mtd_partition *part, int partno, 378 uint64_t cur_offset) 379 { 380 struct mtd_part *slave; 381 char *name; 382 383 /* allocate the partition structure */ 384 slave = kzalloc(sizeof(*slave), GFP_KERNEL); 385 name = kstrdup(part->name, GFP_KERNEL); 386 if (!name || !slave) { 387 printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n", 388 master->name); 389 kfree(name); 390 kfree(slave); 391 return ERR_PTR(-ENOMEM); 392 } 393 394 /* set up the MTD object for this partition */ 395 slave->mtd.type = master->type; 396 slave->mtd.flags = master->flags & ~part->mask_flags; 397 slave->mtd.size = part->size; 398 slave->mtd.writesize = master->writesize; 399 slave->mtd.writebufsize = master->writebufsize; 400 slave->mtd.oobsize = master->oobsize; 401 slave->mtd.oobavail = master->oobavail; 402 slave->mtd.subpage_sft = master->subpage_sft; 403 404 slave->mtd.name = name; 405 slave->mtd.owner = master->owner; 406 slave->mtd.backing_dev_info = master->backing_dev_info; 407 408 /* NOTE: we don't arrange MTDs as a tree; it'd be error-prone 409 * to have the same data be in two different partitions. 410 */ 411 slave->mtd.dev.parent = master->dev.parent; 412 413 slave->mtd.read = part_read; 414 slave->mtd.write = part_write; 415 416 if (master->panic_write) 417 slave->mtd.panic_write = part_panic_write; 418 419 if (master->point && master->unpoint) { 420 slave->mtd.point = part_point; 421 slave->mtd.unpoint = part_unpoint; 422 } 423 424 if (master->get_unmapped_area) 425 slave->mtd.get_unmapped_area = part_get_unmapped_area; 426 if (master->read_oob) 427 slave->mtd.read_oob = part_read_oob; 428 if (master->write_oob) 429 slave->mtd.write_oob = part_write_oob; 430 if (master->read_user_prot_reg) 431 slave->mtd.read_user_prot_reg = part_read_user_prot_reg; 432 if (master->read_fact_prot_reg) 433 slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg; 434 if (master->write_user_prot_reg) 435 slave->mtd.write_user_prot_reg = part_write_user_prot_reg; 436 if (master->lock_user_prot_reg) 437 slave->mtd.lock_user_prot_reg = part_lock_user_prot_reg; 438 if (master->get_user_prot_info) 439 slave->mtd.get_user_prot_info = part_get_user_prot_info; 440 if (master->get_fact_prot_info) 441 slave->mtd.get_fact_prot_info = part_get_fact_prot_info; 442 if (master->sync) 443 slave->mtd.sync = part_sync; 444 if (!partno && !master->dev.class && master->suspend && master->resume) { 445 slave->mtd.suspend = part_suspend; 446 slave->mtd.resume = part_resume; 447 } 448 if (master->writev) 449 slave->mtd.writev = part_writev; 450 if (master->lock) 451 slave->mtd.lock = part_lock; 452 if (master->unlock) 453 slave->mtd.unlock = part_unlock; 454 if (master->is_locked) 455 slave->mtd.is_locked = part_is_locked; 456 if (master->block_isbad) 457 slave->mtd.block_isbad = part_block_isbad; 458 if (master->block_markbad) 459 slave->mtd.block_markbad = part_block_markbad; 460 slave->mtd.erase = part_erase; 461 slave->master = master; 462 slave->offset = part->offset; 463 464 if (slave->offset == MTDPART_OFS_APPEND) 465 slave->offset = cur_offset; 466 if (slave->offset == MTDPART_OFS_NXTBLK) { 467 slave->offset = cur_offset; 468 if (mtd_mod_by_eb(cur_offset, master) != 0) { 469 /* Round up to next erasesize */ 470 slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize; 471 printk(KERN_NOTICE "Moving partition %d: " 472 "0x%012llx -> 0x%012llx\n", partno, 473 (unsigned long long)cur_offset, (unsigned long long)slave->offset); 474 } 475 } 476 if (slave->offset == MTDPART_OFS_RETAIN) { 477 slave->offset = cur_offset; 478 if (master->size - slave->offset >= slave->mtd.size) { 479 slave->mtd.size = master->size - slave->offset 480 - slave->mtd.size; 481 } else { 482 printk(KERN_ERR "mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n", 483 part->name, master->size - slave->offset, 484 slave->mtd.size); 485 /* register to preserve ordering */ 486 goto out_register; 487 } 488 } 489 if (slave->mtd.size == MTDPART_SIZ_FULL) 490 slave->mtd.size = master->size - slave->offset; 491 492 printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset, 493 (unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name); 494 495 /* let's do some sanity checks */ 496 if (slave->offset >= master->size) { 497 /* let's register it anyway to preserve ordering */ 498 slave->offset = 0; 499 slave->mtd.size = 0; 500 printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n", 501 part->name); 502 goto out_register; 503 } 504 if (slave->offset + slave->mtd.size > master->size) { 505 slave->mtd.size = master->size - slave->offset; 506 printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n", 507 part->name, master->name, (unsigned long long)slave->mtd.size); 508 } 509 if (master->numeraseregions > 1) { 510 /* Deal with variable erase size stuff */ 511 int i, max = master->numeraseregions; 512 u64 end = slave->offset + slave->mtd.size; 513 struct mtd_erase_region_info *regions = master->eraseregions; 514 515 /* Find the first erase regions which is part of this 516 * partition. */ 517 for (i = 0; i < max && regions[i].offset <= slave->offset; i++) 518 ; 519 /* The loop searched for the region _behind_ the first one */ 520 if (i > 0) 521 i--; 522 523 /* Pick biggest erasesize */ 524 for (; i < max && regions[i].offset < end; i++) { 525 if (slave->mtd.erasesize < regions[i].erasesize) { 526 slave->mtd.erasesize = regions[i].erasesize; 527 } 528 } 529 BUG_ON(slave->mtd.erasesize == 0); 530 } else { 531 /* Single erase size */ 532 slave->mtd.erasesize = master->erasesize; 533 } 534 535 if ((slave->mtd.flags & MTD_WRITEABLE) && 536 mtd_mod_by_eb(slave->offset, &slave->mtd)) { 537 /* Doesn't start on a boundary of major erase size */ 538 /* FIXME: Let it be writable if it is on a boundary of 539 * _minor_ erase size though */ 540 slave->mtd.flags &= ~MTD_WRITEABLE; 541 printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n", 542 part->name); 543 } 544 if ((slave->mtd.flags & MTD_WRITEABLE) && 545 mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) { 546 slave->mtd.flags &= ~MTD_WRITEABLE; 547 printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n", 548 part->name); 549 } 550 551 slave->mtd.ecclayout = master->ecclayout; 552 if (master->block_isbad) { 553 uint64_t offs = 0; 554 555 while (offs < slave->mtd.size) { 556 if (mtd_block_isbad(master, offs + slave->offset)) 557 slave->mtd.ecc_stats.badblocks++; 558 offs += slave->mtd.erasesize; 559 } 560 } 561 562 out_register: 563 return slave; 564 } 565 566 int mtd_add_partition(struct mtd_info *master, char *name, 567 long long offset, long long length) 568 { 569 struct mtd_partition part; 570 struct mtd_part *p, *new; 571 uint64_t start, end; 572 int ret = 0; 573 574 /* the direct offset is expected */ 575 if (offset == MTDPART_OFS_APPEND || 576 offset == MTDPART_OFS_NXTBLK) 577 return -EINVAL; 578 579 if (length == MTDPART_SIZ_FULL) 580 length = master->size - offset; 581 582 if (length <= 0) 583 return -EINVAL; 584 585 part.name = name; 586 part.size = length; 587 part.offset = offset; 588 part.mask_flags = 0; 589 part.ecclayout = NULL; 590 591 new = allocate_partition(master, &part, -1, offset); 592 if (IS_ERR(new)) 593 return PTR_ERR(new); 594 595 start = offset; 596 end = offset + length; 597 598 mutex_lock(&mtd_partitions_mutex); 599 list_for_each_entry(p, &mtd_partitions, list) 600 if (p->master == master) { 601 if ((start >= p->offset) && 602 (start < (p->offset + p->mtd.size))) 603 goto err_inv; 604 605 if ((end >= p->offset) && 606 (end < (p->offset + p->mtd.size))) 607 goto err_inv; 608 } 609 610 list_add(&new->list, &mtd_partitions); 611 mutex_unlock(&mtd_partitions_mutex); 612 613 add_mtd_device(&new->mtd); 614 615 return ret; 616 err_inv: 617 mutex_unlock(&mtd_partitions_mutex); 618 free_partition(new); 619 return -EINVAL; 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 ret = del_mtd_device(&slave->mtd); 633 if (ret < 0) 634 break; 635 636 list_del(&slave->list); 637 free_partition(slave); 638 break; 639 } 640 mutex_unlock(&mtd_partitions_mutex); 641 642 return ret; 643 } 644 EXPORT_SYMBOL_GPL(mtd_del_partition); 645 646 /* 647 * This function, given a master MTD object and a partition table, creates 648 * and registers slave MTD objects which are bound to the master according to 649 * the partition definitions. 650 * 651 * We don't register the master, or expect the caller to have done so, 652 * for reasons of data integrity. 653 */ 654 655 int add_mtd_partitions(struct mtd_info *master, 656 const struct mtd_partition *parts, 657 int nbparts) 658 { 659 struct mtd_part *slave; 660 uint64_t cur_offset = 0; 661 int i; 662 663 printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name); 664 665 for (i = 0; i < nbparts; i++) { 666 slave = allocate_partition(master, parts + i, i, cur_offset); 667 if (IS_ERR(slave)) 668 return PTR_ERR(slave); 669 670 mutex_lock(&mtd_partitions_mutex); 671 list_add(&slave->list, &mtd_partitions); 672 mutex_unlock(&mtd_partitions_mutex); 673 674 add_mtd_device(&slave->mtd); 675 676 cur_offset = slave->offset + slave->mtd.size; 677 } 678 679 return 0; 680 } 681 682 static DEFINE_SPINLOCK(part_parser_lock); 683 static LIST_HEAD(part_parsers); 684 685 static struct mtd_part_parser *get_partition_parser(const char *name) 686 { 687 struct mtd_part_parser *p, *ret = NULL; 688 689 spin_lock(&part_parser_lock); 690 691 list_for_each_entry(p, &part_parsers, list) 692 if (!strcmp(p->name, name) && try_module_get(p->owner)) { 693 ret = p; 694 break; 695 } 696 697 spin_unlock(&part_parser_lock); 698 699 return ret; 700 } 701 702 #define put_partition_parser(p) do { module_put((p)->owner); } while (0) 703 704 int register_mtd_parser(struct mtd_part_parser *p) 705 { 706 spin_lock(&part_parser_lock); 707 list_add(&p->list, &part_parsers); 708 spin_unlock(&part_parser_lock); 709 710 return 0; 711 } 712 EXPORT_SYMBOL_GPL(register_mtd_parser); 713 714 int deregister_mtd_parser(struct mtd_part_parser *p) 715 { 716 spin_lock(&part_parser_lock); 717 list_del(&p->list); 718 spin_unlock(&part_parser_lock); 719 return 0; 720 } 721 EXPORT_SYMBOL_GPL(deregister_mtd_parser); 722 723 /* 724 * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you 725 * are changing this array! 726 */ 727 static const char *default_mtd_part_types[] = { 728 "cmdlinepart", 729 "ofpart", 730 NULL 731 }; 732 733 /** 734 * parse_mtd_partitions - parse MTD partitions 735 * @master: the master partition (describes whole MTD device) 736 * @types: names of partition parsers to try or %NULL 737 * @pparts: array of partitions found is returned here 738 * @data: MTD partition parser-specific data 739 * 740 * This function tries to find partition on MTD device @master. It uses MTD 741 * partition parsers, specified in @types. However, if @types is %NULL, then 742 * the default list of parsers is used. The default list contains only the 743 * "cmdlinepart" and "ofpart" parsers ATM. 744 * 745 * This function may return: 746 * o a negative error code in case of failure 747 * o zero if no partitions were found 748 * o a positive number of found partitions, in which case on exit @pparts will 749 * point to an array containing this number of &struct mtd_info objects. 750 */ 751 int parse_mtd_partitions(struct mtd_info *master, const char **types, 752 struct mtd_partition **pparts, 753 struct mtd_part_parser_data *data) 754 { 755 struct mtd_part_parser *parser; 756 int ret = 0; 757 758 if (!types) 759 types = default_mtd_part_types; 760 761 for ( ; ret <= 0 && *types; types++) { 762 parser = get_partition_parser(*types); 763 if (!parser && !request_module("%s", *types)) 764 parser = get_partition_parser(*types); 765 if (!parser) 766 continue; 767 ret = (*parser->parse_fn)(master, pparts, data); 768 if (ret > 0) { 769 printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n", 770 ret, parser->name, master->name); 771 } 772 put_partition_parser(parser); 773 } 774 return ret; 775 } 776 777 int mtd_is_partition(struct mtd_info *mtd) 778 { 779 struct mtd_part *part; 780 int ispart = 0; 781 782 mutex_lock(&mtd_partitions_mutex); 783 list_for_each_entry(part, &mtd_partitions, list) 784 if (&part->mtd == mtd) { 785 ispart = 1; 786 break; 787 } 788 mutex_unlock(&mtd_partitions_mutex); 789 790 return ispart; 791 } 792 EXPORT_SYMBOL_GPL(mtd_is_partition); 793