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  * SPDX-License-Identifier:     GPL-2.0+
   9  *
  10  */
  11
  12 #ifndef __UBOOT__
  13 #include <linux/module.h>
  14 #include <linux/types.h>
  15 #include <linux/kernel.h>
  16 #include <linux/slab.h>
  17 #include <linux/list.h>
  18 #include <linux/kmod.h>
  19 #endif
  20
  21 #include <common.h>
  22 #include <malloc.h>
  23 #include <asm/errno.h>
  24 #include <linux/compat.h>
  25 #include <ubi_uboot.h>
  26
  27 #include <linux/mtd/mtd.h>
  28 #include <linux/mtd/partitions.h>
  29 #include <linux/err.h>
  30
  31 #include "mtdcore.h"
  32
  33 /* Our partition linked list */
  34 static LIST_HEAD(mtd_partitions);
  35 #ifndef __UBOOT__
  36 static DEFINE_MUTEX(mtd_partitions_mutex);
  37 #else
  38 DEFINE_MUTEX(mtd_partitions_mutex);
  39 #endif
  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 with this macro.
  52  */
  53 #define PART(x)  ((struct mtd_part *)(x))
  54
  55
  56 #ifdef __UBOOT__
  57 /* from mm/util.c */
  58
  59 /**
  60  * kstrdup - allocate space for and copy an existing string
  61  * @s: the string to duplicate
  62  * @gfp: the GFP mask used in the kmalloc() call when allocating memory
  63  */
  64 char *kstrdup(const char *s, gfp_t gfp)
  65 {
  66         size_t len;
  67         char *buf;
  68
  69         if (!s)
  70                 return NULL;
  71
  72         len = strlen(s) + 1;
  73         buf = kmalloc(len, gfp);
  74         if (buf)
  75                 memcpy(buf, s, len);
  76         return buf;
  77 }
  78 #endif
  79
  80 /*
  81  * MTD methods which simply translate the effective address and pass through
  82  * to the _real_ device.
  83  */
  84
  85 static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
  86                 size_t *retlen, u_char *buf)
  87 {
  88         struct mtd_part *part = PART(mtd);
  89         struct mtd_ecc_stats stats;
  90         int res;
  91
  92         stats = part->master->ecc_stats;
  93         res = part->master->_read(part->master, from + part->offset, len,
  94                                   retlen, buf);
  95         if (unlikely(mtd_is_eccerr(res)))
  96                 mtd->ecc_stats.failed +=
  97                         part->master->ecc_stats.failed - stats.failed;
  98         else
  99                 mtd->ecc_stats.corrected +=
 100                         part->master->ecc_stats.corrected - stats.corrected;
 101         return res;
 102 }
 103
 104 #ifndef __UBOOT__
 105 static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
 106                 size_t *retlen, void **virt, resource_size_t *phys)
 107 {
 108         struct mtd_part *part = PART(mtd);
 109
 110         return part->master->_point(part->master, from + part->offset, len,
 111                                     retlen, virt, phys);
 112 }
 113
 114 static int part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
 115 {
 116         struct mtd_part *part = PART(mtd);
 117
 118         return part->master->_unpoint(part->master, from + part->offset, len);
 119 }
 120 #endif
 121
 122 static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
 123                                             unsigned long len,
 124                                             unsigned long offset,
 125                                             unsigned long flags)
 126 {
 127         struct mtd_part *part = PART(mtd);
 128
 129         offset += part->offset;
 130         return part->master->_get_unmapped_area(part->master, len, offset,
 131                                                 flags);
 132 }
 133
 134 static int part_read_oob(struct mtd_info *mtd, loff_t from,
 135                 struct mtd_oob_ops *ops)
 136 {
 137         struct mtd_part *part = PART(mtd);
 138         int res;
 139
 140         if (from >= mtd->size)
 141                 return -EINVAL;
 142         if (ops->datbuf && from + ops->len > mtd->size)
 143                 return -EINVAL;
 144
 145         /*
 146          * If OOB is also requested, make sure that we do not read past the end
 147          * of this partition.
 148          */
 149         if (ops->oobbuf) {
 150                 size_t len, pages;
 151
 152                 if (ops->mode == MTD_OPS_AUTO_OOB)
 153                         len = mtd->oobavail;
 154                 else
 155                         len = mtd->oobsize;
 156                 pages = mtd_div_by_ws(mtd->size, mtd);
 157                 pages -= mtd_div_by_ws(from, mtd);
 158                 if (ops->ooboffs + ops->ooblen > pages * len)
 159                         return -EINVAL;
 160         }
 161
 162         res = part->master->_read_oob(part->master, from + part->offset, ops);
 163         if (unlikely(res)) {
 164                 if (mtd_is_bitflip(res))
 165                         mtd->ecc_stats.corrected++;
 166                 if (mtd_is_eccerr(res))
 167                         mtd->ecc_stats.failed++;
 168         }
 169         return res;
 170 }
 171
 172 static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
 173                 size_t len, size_t *retlen, u_char *buf)
 174 {
 175         struct mtd_part *part = PART(mtd);
 176         return part->master->_read_user_prot_reg(part->master, from, len,
 177                                                  retlen, buf);
 178 }
 179
 180 static int part_get_user_prot_info(struct mtd_info *mtd, size_t len,
 181                                    size_t *retlen, struct otp_info *buf)
 182 {
 183         struct mtd_part *part = PART(mtd);
 184         return part->master->_get_user_prot_info(part->master, len, retlen,
 185                                                  buf);
 186 }
 187
 188 static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
 189                 size_t len, size_t *retlen, u_char *buf)
 190 {
 191         struct mtd_part *part = PART(mtd);
 192         return part->master->_read_fact_prot_reg(part->master, from, len,
 193                                                  retlen, buf);
 194 }
 195
 196 static int part_get_fact_prot_info(struct mtd_info *mtd, size_t len,
 197                                    size_t *retlen, struct otp_info *buf)
 198 {
 199         struct mtd_part *part = PART(mtd);
 200         return part->master->_get_fact_prot_info(part->master, len, retlen,
 201                                                  buf);
 202 }
 203
 204 static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
 205                 size_t *retlen, const u_char *buf)
 206 {
 207         struct mtd_part *part = PART(mtd);
 208         return part->master->_write(part->master, to + part->offset, len,
 209                                     retlen, buf);
 210 }
 211
 212 static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
 213                 size_t *retlen, const u_char *buf)
 214 {
 215         struct mtd_part *part = PART(mtd);
 216         return part->master->_panic_write(part->master, to + part->offset, len,
 217                                           retlen, buf);
 218 }
 219
 220 static int part_write_oob(struct mtd_info *mtd, loff_t to,
 221                 struct mtd_oob_ops *ops)
 222 {
 223         struct mtd_part *part = PART(mtd);
 224
 225         if (to >= mtd->size)
 226                 return -EINVAL;
 227         if (ops->datbuf && to + ops->len > mtd->size)
 228                 return -EINVAL;
 229         return part->master->_write_oob(part->master, to + part->offset, ops);
 230 }
 231
 232 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
 233                 size_t len, size_t *retlen, u_char *buf)
 234 {
 235         struct mtd_part *part = PART(mtd);
 236         return part->master->_write_user_prot_reg(part->master, from, len,
 237                                                   retlen, buf);
 238 }
 239
 240 static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
 241                 size_t len)
 242 {
 243         struct mtd_part *part = PART(mtd);
 244         return part->master->_lock_user_prot_reg(part->master, from, len);
 245 }
 246
 247 #ifndef __UBOOT__
 248 static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
 249                 unsigned long count, loff_t to, size_t *retlen)
 250 {
 251         struct mtd_part *part = PART(mtd);
 252         return part->master->_writev(part->master, vecs, count,
 253                                      to + part->offset, retlen);
 254 }
 255 #endif
 256
 257 static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
 258 {
 259         struct mtd_part *part = PART(mtd);
 260         int ret;
 261
 262         instr->addr += part->offset;
 263         ret = part->master->_erase(part->master, instr);
 264         if (ret) {
 265                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 266                         instr->fail_addr -= part->offset;
 267                 instr->addr -= part->offset;
 268         }
 269         return ret;
 270 }
 271
 272 void mtd_erase_callback(struct erase_info *instr)
 273 {
 274         if (instr->mtd->_erase == part_erase) {
 275                 struct mtd_part *part = PART(instr->mtd);
 276
 277                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 278                         instr->fail_addr -= part->offset;
 279                 instr->addr -= part->offset;
 280         }
 281         if (instr->callback)
 282                 instr->callback(instr);
 283 }
 284 EXPORT_SYMBOL_GPL(mtd_erase_callback);
 285
 286 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 287 {
 288         struct mtd_part *part = PART(mtd);
 289         return part->master->_lock(part->master, ofs + part->offset, len);
 290 }
 291
 292 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 293 {
 294         struct mtd_part *part = PART(mtd);
 295         return part->master->_unlock(part->master, ofs + part->offset, len);
 296 }
 297
 298 static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 299 {
 300         struct mtd_part *part = PART(mtd);
 301         return part->master->_is_locked(part->master, ofs + part->offset, len);
 302 }
 303
 304 static void part_sync(struct mtd_info *mtd)
 305 {
 306         struct mtd_part *part = PART(mtd);
 307         part->master->_sync(part->master);
 308 }
 309
 310 #ifndef __UBOOT__
 311 static int part_suspend(struct mtd_info *mtd)
 312 {
 313         struct mtd_part *part = PART(mtd);
 314         return part->master->_suspend(part->master);
 315 }
 316
 317 static void part_resume(struct mtd_info *mtd)
 318 {
 319         struct mtd_part *part = PART(mtd);
 320         part->master->_resume(part->master);
 321 }
 322 #endif
 323
 324 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
 325 {
 326         struct mtd_part *part = PART(mtd);
 327         ofs += part->offset;
 328         return part->master->_block_isbad(part->master, ofs);
 329 }
 330
 331 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
 332 {
 333         struct mtd_part *part = PART(mtd);
 334         int res;
 335
 336         ofs += part->offset;
 337         res = part->master->_block_markbad(part->master, ofs);
 338         if (!res)
 339                 mtd->ecc_stats.badblocks++;
 340         return res;
 341 }
 342
 343 static inline void free_partition(struct mtd_part *p)
 344 {
 345         kfree(p->mtd.name);
 346         kfree(p);
 347 }
 348
 349 /*
 350  * This function unregisters and destroy all slave MTD objects which are
 351  * attached to the given master MTD object.
 352  */
 353
 354 int del_mtd_partitions(struct mtd_info *master)
 355 {
 356         struct mtd_part *slave, *next;
 357         int ret, err = 0;
 358
 359         mutex_lock(&mtd_partitions_mutex);
 360         list_for_each_entry_safe(slave, next, &mtd_partitions, list)
 361                 if (slave->master == master) {
 362                         ret = del_mtd_device(&slave->mtd);
 363                         if (ret < 0) {
 364                                 err = ret;
 365                                 continue;
 366                         }
 367                         list_del(&slave->list);
 368                         free_partition(slave);
 369                 }
 370         mutex_unlock(&mtd_partitions_mutex);
 371
 372         return err;
 373 }
 374
 375 static struct mtd_part *allocate_partition(struct mtd_info *master,
 376                         const struct mtd_partition *part, int partno,
 377                         uint64_t cur_offset)
 378 {
 379         struct mtd_part *slave;
 380         char *name;
 381
 382         /* allocate the partition structure */
 383         slave = kzalloc(sizeof(*slave), GFP_KERNEL);
 384         name = kstrdup(part->name, GFP_KERNEL);
 385         if (!name || !slave) {
 386                 printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
 387                        master->name);
 388                 kfree(name);
 389                 kfree(slave);
 390                 return ERR_PTR(-ENOMEM);
 391         }
 392
 393         /* set up the MTD object for this partition */
 394         slave->mtd.type = master->type;
 395         slave->mtd.flags = master->flags & ~part->mask_flags;
 396         slave->mtd.size = part->size;
 397         slave->mtd.writesize = master->writesize;
 398         slave->mtd.writebufsize = master->writebufsize;
 399         slave->mtd.oobsize = master->oobsize;
 400         slave->mtd.oobavail = master->oobavail;
 401         slave->mtd.subpage_sft = master->subpage_sft;
 402
 403         slave->mtd.name = name;
 404         slave->mtd.owner = master->owner;
 405 #ifndef __UBOOT__
 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 #endif
 413
 414         slave->mtd._read = part_read;
 415         slave->mtd._write = part_write;
 416
 417         if (master->_panic_write)
 418                 slave->mtd._panic_write = part_panic_write;
 419
 420 #ifndef __UBOOT__
 421         if (master->_point && master->_unpoint) {
 422                 slave->mtd._point = part_point;
 423                 slave->mtd._unpoint = part_unpoint;
 424         }
 425 #endif
 426
 427         if (master->_get_unmapped_area)
 428                 slave->mtd._get_unmapped_area = part_get_unmapped_area;
 429         if (master->_read_oob)
 430                 slave->mtd._read_oob = part_read_oob;
 431         if (master->_write_oob)
 432                 slave->mtd._write_oob = part_write_oob;
 433         if (master->_read_user_prot_reg)
 434                 slave->mtd._read_user_prot_reg = part_read_user_prot_reg;
 435         if (master->_read_fact_prot_reg)
 436                 slave->mtd._read_fact_prot_reg = part_read_fact_prot_reg;
 437         if (master->_write_user_prot_reg)
 438                 slave->mtd._write_user_prot_reg = part_write_user_prot_reg;
 439         if (master->_lock_user_prot_reg)
 440                 slave->mtd._lock_user_prot_reg = part_lock_user_prot_reg;
 441         if (master->_get_user_prot_info)
 442                 slave->mtd._get_user_prot_info = part_get_user_prot_info;
 443         if (master->_get_fact_prot_info)
 444                 slave->mtd._get_fact_prot_info = part_get_fact_prot_info;
 445         if (master->_sync)
 446                 slave->mtd._sync = part_sync;
 447 #ifndef __UBOOT__
 448         if (!partno && !master->dev.class && master->_suspend &&
 449             master->_resume) {
 450                         slave->mtd._suspend = part_suspend;
 451                         slave->mtd._resume = part_resume;
 452         }
 453         if (master->_writev)
 454                 slave->mtd._writev = part_writev;
 455 #endif
 456         if (master->_lock)
 457                 slave->mtd._lock = part_lock;
 458         if (master->_unlock)
 459                 slave->mtd._unlock = part_unlock;
 460         if (master->_is_locked)
 461                 slave->mtd._is_locked = part_is_locked;
 462         if (master->_block_isbad)
 463                 slave->mtd._block_isbad = part_block_isbad;
 464         if (master->_block_markbad)
 465                 slave->mtd._block_markbad = part_block_markbad;
 466         slave->mtd._erase = part_erase;
 467         slave->master = master;
 468         slave->offset = part->offset;
 469
 470         if (slave->offset == MTDPART_OFS_APPEND)
 471                 slave->offset = cur_offset;
 472         if (slave->offset == MTDPART_OFS_NXTBLK) {
 473                 slave->offset = cur_offset;
 474                 if (mtd_mod_by_eb(cur_offset, master) != 0) {
 475                         /* Round up to next erasesize */
 476                         slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
 477                         debug("Moving partition %d: "
 478                                "0x%012llx -> 0x%012llx\n", partno,
 479                                (unsigned long long)cur_offset, (unsigned long long)slave->offset);
 480                 }
 481         }
 482         if (slave->offset == MTDPART_OFS_RETAIN) {
 483                 slave->offset = cur_offset;
 484                 if (master->size - slave->offset >= slave->mtd.size) {
 485                         slave->mtd.size = master->size - slave->offset
 486                                                         - slave->mtd.size;
 487                 } else {
 488                         debug("mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
 489                                 part->name, master->size - slave->offset,
 490                                 slave->mtd.size);
 491                         /* register to preserve ordering */
 492                         goto out_register;
 493                 }
 494         }
 495         if (slave->mtd.size == MTDPART_SIZ_FULL)
 496                 slave->mtd.size = master->size - slave->offset;
 497
 498         debug("0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
 499                 (unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
 500
 501         /* let's do some sanity checks */
 502         if (slave->offset >= master->size) {
 503                 /* let's register it anyway to preserve ordering */
 504                 slave->offset = 0;
 505                 slave->mtd.size = 0;
 506                 printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
 507                         part->name);
 508                 goto out_register;
 509         }
 510         if (slave->offset + slave->mtd.size > master->size) {
 511                 slave->mtd.size = master->size - slave->offset;
 512                 printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
 513                         part->name, master->name, (unsigned long long)slave->mtd.size);
 514         }
 515         if (master->numeraseregions > 1) {
 516                 /* Deal with variable erase size stuff */
 517                 int i, max = master->numeraseregions;
 518                 u64 end = slave->offset + slave->mtd.size;
 519                 struct mtd_erase_region_info *regions = master->eraseregions;
 520
 521                 /* Find the first erase regions which is part of this
 522                  * partition. */
 523                 for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
 524                         ;
 525                 /* The loop searched for the region _behind_ the first one */
 526                 if (i > 0)
 527                         i--;
 528
 529                 /* Pick biggest erasesize */
 530                 for (; i < max && regions[i].offset < end; i++) {
 531                         if (slave->mtd.erasesize < regions[i].erasesize) {
 532                                 slave->mtd.erasesize = regions[i].erasesize;
 533                         }
 534                 }
 535                 BUG_ON(slave->mtd.erasesize == 0);
 536         } else {
 537                 /* Single erase size */
 538                 slave->mtd.erasesize = master->erasesize;
 539         }
 540
 541         if ((slave->mtd.flags & MTD_WRITEABLE) &&
 542             mtd_mod_by_eb(slave->offset, &slave->mtd)) {
 543                 /* Doesn't start on a boundary of major erase size */
 544                 /* FIXME: Let it be writable if it is on a boundary of
 545                  * _minor_ erase size though */
 546                 slave->mtd.flags &= ~MTD_WRITEABLE;
 547                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
 548                         part->name);
 549         }
 550         if ((slave->mtd.flags & MTD_WRITEABLE) &&
 551             mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
 552                 slave->mtd.flags &= ~MTD_WRITEABLE;
 553                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
 554                         part->name);
 555         }
 556
 557         slave->mtd.ecclayout = master->ecclayout;
 558         slave->mtd.ecc_step_size = master->ecc_step_size;
 559         slave->mtd.ecc_strength = master->ecc_strength;
 560         slave->mtd.bitflip_threshold = master->bitflip_threshold;
 561
 562         if (master->_block_isbad) {
 563                 uint64_t offs = 0;
 564
 565                 while (offs < slave->mtd.size) {
 566                         if (mtd_block_isbad(master, offs + slave->offset))
 567                                 slave->mtd.ecc_stats.badblocks++;
 568                         offs += slave->mtd.erasesize;
 569                 }
 570         }
 571
 572 out_register:
 573         return slave;
 574 }
 575
 576 #ifndef __UBOOT__
 577 int mtd_add_partition(struct mtd_info *master, const char *name,
 578                       long long offset, long long length)
 579 {
 580         struct mtd_partition part;
 581         struct mtd_part *p, *new;
 582         uint64_t start, end;
 583         int ret = 0;
 584
 585         /* the direct offset is expected */
 586         if (offset == MTDPART_OFS_APPEND ||
 587             offset == MTDPART_OFS_NXTBLK)
 588                 return -EINVAL;
 589
 590         if (length == MTDPART_SIZ_FULL)
 591                 length = master->size - offset;
 592
 593         if (length <= 0)
 594                 return -EINVAL;
 595
 596         part.name = name;
 597         part.size = length;
 598         part.offset = offset;
 599         part.mask_flags = 0;
 600         part.ecclayout = NULL;
 601
 602         new = allocate_partition(master, &part, -1, offset);
 603         if (IS_ERR(new))
 604                 return PTR_ERR(new);
 605
 606         start = offset;
 607         end = offset + length;
 608
 609         mutex_lock(&mtd_partitions_mutex);
 610         list_for_each_entry(p, &mtd_partitions, list)
 611                 if (p->master == master) {
 612                         if ((start >= p->offset) &&
 613                             (start < (p->offset + p->mtd.size)))
 614                                 goto err_inv;
 615
 616                         if ((end >= p->offset) &&
 617                             (end < (p->offset + p->mtd.size)))
 618                                 goto err_inv;
 619                 }
 620
 621         list_add(&new->list, &mtd_partitions);
 622         mutex_unlock(&mtd_partitions_mutex);
 623
 624         add_mtd_device(&new->mtd);
 625
 626         return ret;
 627 err_inv:
 628         mutex_unlock(&mtd_partitions_mutex);
 629         free_partition(new);
 630         return -EINVAL;
 631 }
 632 EXPORT_SYMBOL_GPL(mtd_add_partition);
 633
 634 int mtd_del_partition(struct mtd_info *master, int partno)
 635 {
 636         struct mtd_part *slave, *next;
 637         int ret = -EINVAL;
 638
 639         mutex_lock(&mtd_partitions_mutex);
 640         list_for_each_entry_safe(slave, next, &mtd_partitions, list)
 641                 if ((slave->master == master) &&
 642                     (slave->mtd.index == partno)) {
 643                         ret = del_mtd_device(&slave->mtd);
 644                         if (ret < 0)
 645                                 break;
 646
 647                         list_del(&slave->list);
 648                         free_partition(slave);
 649                         break;
 650                 }
 651         mutex_unlock(&mtd_partitions_mutex);
 652
 653         return ret;
 654 }
 655 EXPORT_SYMBOL_GPL(mtd_del_partition);
 656 #endif
 657
 658 /*
 659  * This function, given a master MTD object and a partition table, creates
 660  * and registers slave MTD objects which are bound to the master according to
 661  * the partition definitions.
 662  *
 663  * We don't register the master, or expect the caller to have done so,
 664  * for reasons of data integrity.
 665  */
 666
 667 int add_mtd_partitions(struct mtd_info *master,
 668                        const struct mtd_partition *parts,
 669                        int nbparts)
 670 {
 671         struct mtd_part *slave;
 672         uint64_t cur_offset = 0;
 673         int i;
 674
 675 #ifdef __UBOOT__
 676         /*
 677          * Need to init the list here, since LIST_INIT() does not
 678          * work on platforms where relocation has problems (like MIPS
 679          * & PPC).
 680          */
 681         if (mtd_partitions.next == NULL)
 682                 INIT_LIST_HEAD(&mtd_partitions);
 683 #endif
 684
 685         debug("Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
 686
 687         for (i = 0; i < nbparts; i++) {
 688                 slave = allocate_partition(master, parts + i, i, cur_offset);
 689                 if (IS_ERR(slave))
 690                         return PTR_ERR(slave);
 691
 692                 mutex_lock(&mtd_partitions_mutex);
 693                 list_add(&slave->list, &mtd_partitions);
 694                 mutex_unlock(&mtd_partitions_mutex);
 695
 696                 add_mtd_device(&slave->mtd);
 697
 698                 cur_offset = slave->offset + slave->mtd.size;
 699         }
 700
 701         return 0;
 702 }
 703
 704 #ifndef __UBOOT__
 705 static DEFINE_SPINLOCK(part_parser_lock);
 706 static LIST_HEAD(part_parsers);
 707
 708 static struct mtd_part_parser *get_partition_parser(const char *name)
 709 {
 710         struct mtd_part_parser *p, *ret = NULL;
 711
 712         spin_lock(&part_parser_lock);
 713
 714         list_for_each_entry(p, &part_parsers, list)
 715                 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
 716                         ret = p;
 717                         break;
 718                 }
 719
 720         spin_unlock(&part_parser_lock);
 721
 722         return ret;
 723 }
 724
 725 #define put_partition_parser(p) do { module_put((p)->owner); } while (0)
 726
 727 void register_mtd_parser(struct mtd_part_parser *p)
 728 {
 729         spin_lock(&part_parser_lock);
 730         list_add(&p->list, &part_parsers);
 731         spin_unlock(&part_parser_lock);
 732 }
 733 EXPORT_SYMBOL_GPL(register_mtd_parser);
 734
 735 void deregister_mtd_parser(struct mtd_part_parser *p)
 736 {
 737         spin_lock(&part_parser_lock);
 738         list_del(&p->list);
 739         spin_unlock(&part_parser_lock);
 740 }
 741 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
 742
 743 /*
 744  * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
 745  * are changing this array!
 746  */
 747 static const char * const default_mtd_part_types[] = {
 748         "cmdlinepart",
 749         "ofpart",
 750         NULL
 751 };
 752
 753 /**
 754  * parse_mtd_partitions - parse MTD partitions
 755  * @master: the master partition (describes whole MTD device)
 756  * @types: names of partition parsers to try or %NULL
 757  * @pparts: array of partitions found is returned here
 758  * @data: MTD partition parser-specific data
 759  *
 760  * This function tries to find partition on MTD device @master. It uses MTD
 761  * partition parsers, specified in @types. However, if @types is %NULL, then
 762  * the default list of parsers is used. The default list contains only the
 763  * "cmdlinepart" and "ofpart" parsers ATM.
 764  * Note: If there are more then one parser in @types, the kernel only takes the
 765  * partitions parsed out by the first parser.
 766  *
 767  * This function may return:
 768  * o a negative error code in case of failure
 769  * o zero if no partitions were found
 770  * o a positive number of found partitions, in which case on exit @pparts will
 771  *   point to an array containing this number of &struct mtd_info objects.
 772  */
 773 int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
 774                          struct mtd_partition **pparts,
 775                          struct mtd_part_parser_data *data)
 776 {
 777         struct mtd_part_parser *parser;
 778         int ret = 0;
 779
 780         if (!types)
 781                 types = default_mtd_part_types;
 782
 783         for ( ; ret <= 0 && *types; types++) {
 784                 parser = get_partition_parser(*types);
 785                 if (!parser && !request_module("%s", *types))
 786                         parser = get_partition_parser(*types);
 787                 if (!parser)
 788                         continue;
 789                 ret = (*parser->parse_fn)(master, pparts, data);
 790                 put_partition_parser(parser);
 791                 if (ret > 0) {
 792                         printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
 793                                ret, parser->name, master->name);
 794                         break;
 795                 }
 796         }
 797         return ret;
 798 }
 799 #endif
 800
 801 int mtd_is_partition(const struct mtd_info *mtd)
 802 {
 803         struct mtd_part *part;
 804         int ispart = 0;
 805
 806         mutex_lock(&mtd_partitions_mutex);
 807         list_for_each_entry(part, &mtd_partitions, list)
 808                 if (&part->mtd == mtd) {
 809                         ispart = 1;
 810                         break;
 811                 }
 812         mutex_unlock(&mtd_partitions_mutex);
 813
 814         return ispart;
 815 }
 816 EXPORT_SYMBOL_GPL(mtd_is_partition);
 817
 818 /* Returns the size of the entire flash chip */
 819 uint64_t mtd_get_device_size(const struct mtd_info *mtd)
 820 {
 821         if (!mtd_is_partition(mtd))
 822                 return mtd->size;
 823
 824         return PART(mtd)->master->size;
 825 }
 826 EXPORT_SYMBOL_GPL(mtd_get_device_size);