drivers/mtd/mtdpart.c

   1 /*
   2  * Simple MTD partitioning layer
   3  *
   4  * (C) 2000 Nicolas Pitre <nico@cam.org>
   5  *
   6  * This code is GPL
   7  *
   8  * $Id: mtdpart.c,v 1.41 2003/06/18 14:53:02 dwmw2 Exp $
   9  *
  10  *      02-21-2002      Thomas Gleixner <gleixner@autronix.de>
  11  *                      added support for read_oob, write_oob
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/types.h>
  16 #include <linux/kernel.h>
  17 #include <linux/slab.h>
  18 #include <linux/list.h>
  19 #include <linux/config.h>
  20 #include <linux/kmod.h>
  21 #include <linux/mtd/mtd.h>
  22 #include <linux/mtd/partitions.h>
  23 #include <linux/mtd/compatmac.h>
  24
  25 /* Our partition linked list */
  26 static LIST_HEAD(mtd_partitions);
  27
  28 /* Our partition node structure */
  29 struct mtd_part {
  30         struct mtd_info mtd;
  31         struct mtd_info *master;
  32         u_int32_t offset;
  33         int index;
  34         struct list_head list;
  35         int registered;
  36 };
  37
  38 /*
  39  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
  40  * the pointer to that structure with this macro.
  41  */
  42 #define PART(x)  ((struct mtd_part *)(x))
  43
  44
  45 /*
  46  * MTD methods which simply translate the effective address and pass through
  47  * to the _real_ device.
  48  */
  49
  50 static int part_read (struct mtd_info *mtd, loff_t from, size_t len,
  51                         size_t *retlen, u_char *buf)
  52 {
  53         struct mtd_part *part = PART(mtd);
  54         if (from >= mtd->size)
  55                 len = 0;
  56         else if (from + len > mtd->size)
  57                 len = mtd->size - from;
  58         if (part->master->read_ecc == NULL)
  59                 return part->master->read (part->master, from + part->offset,
  60                                         len, retlen, buf);
  61         else
  62                 return part->master->read_ecc (part->master, from + part->offset,
  63                                         len, retlen, buf, NULL, &mtd->oobinfo);
  64 }
  65
  66 static int part_point (struct mtd_info *mtd, loff_t from, size_t len,
  67                         size_t *retlen, u_char **buf)
  68 {
  69         struct mtd_part *part = PART(mtd);
  70         if (from >= mtd->size)
  71                 len = 0;
  72         else if (from + len > mtd->size)
  73                 len = mtd->size - from;
  74         return part->master->point (part->master, from + part->offset,
  75                                     len, retlen, buf);
  76 }
  77 static void part_unpoint (struct mtd_info *mtd, u_char *addr, loff_t from, size_t len)
  78 {
  79         struct mtd_part *part = PART(mtd);
  80
  81         part->master->unpoint (part->master, addr, from + part->offset, len);
  82 }
  83
  84
  85 static int part_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
  86                         size_t *retlen, u_char *buf, u_char *eccbuf, struct nand_oobinfo *oobsel)
  87 {
  88         struct mtd_part *part = PART(mtd);
  89         if (oobsel == NULL)
  90                 oobsel = &mtd->oobinfo;
  91         if (from >= mtd->size)
  92                 len = 0;
  93         else if (from + len > mtd->size)
  94                 len = mtd->size - from;
  95         return part->master->read_ecc (part->master, from + part->offset,
  96                                         len, retlen, buf, eccbuf, oobsel);
  97 }
  98
  99 static int part_read_oob (struct mtd_info *mtd, loff_t from, size_t len,
 100                         size_t *retlen, u_char *buf)
 101 {
 102         struct mtd_part *part = PART(mtd);
 103         if (from >= mtd->size)
 104                 len = 0;
 105         else if (from + len > mtd->size)
 106                 len = mtd->size - from;
 107         return part->master->read_oob (part->master, from + part->offset,
 108                                         len, retlen, buf);
 109 }
 110
 111 static int part_read_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
 112                         size_t *retlen, u_char *buf)
 113 {
 114         struct mtd_part *part = PART(mtd);
 115         return part->master->read_user_prot_reg (part->master, from,
 116                                         len, retlen, buf);
 117 }
 118
 119 static int part_read_fact_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
 120                         size_t *retlen, u_char *buf)
 121 {
 122         struct mtd_part *part = PART(mtd);
 123         return part->master->read_fact_prot_reg (part->master, from,
 124                                         len, retlen, buf);
 125 }
 126
 127 static int part_write (struct mtd_info *mtd, loff_t to, size_t len,
 128                         size_t *retlen, const u_char *buf)
 129 {
 130         struct mtd_part *part = PART(mtd);
 131         if (!(mtd->flags & MTD_WRITEABLE))
 132                 return -EROFS;
 133         if (to >= mtd->size)
 134                 len = 0;
 135         else if (to + len > mtd->size)
 136                 len = mtd->size - to;
 137         if (part->master->write_ecc == NULL)
 138                 return part->master->write (part->master, to + part->offset,
 139                                         len, retlen, buf);
 140         else
 141                 return part->master->write_ecc (part->master, to + part->offset,
 142                                         len, retlen, buf, NULL, &mtd->oobinfo);
 143
 144 }
 145
 146 static int part_write_ecc (struct mtd_info *mtd, loff_t to, size_t len,
 147                         size_t *retlen, const u_char *buf,
 148                          u_char *eccbuf, struct nand_oobinfo *oobsel)
 149 {
 150         struct mtd_part *part = PART(mtd);
 151         if (!(mtd->flags & MTD_WRITEABLE))
 152                 return -EROFS;
 153         if (oobsel == NULL)
 154                 oobsel = &mtd->oobinfo;
 155         if (to >= mtd->size)
 156                 len = 0;
 157         else if (to + len > mtd->size)
 158                 len = mtd->size - to;
 159         return part->master->write_ecc (part->master, to + part->offset,
 160                                         len, retlen, buf, eccbuf, oobsel);
 161 }
 162
 163 static int part_write_oob (struct mtd_info *mtd, loff_t to, size_t len,
 164                         size_t *retlen, const u_char *buf)
 165 {
 166         struct mtd_part *part = PART(mtd);
 167         if (!(mtd->flags & MTD_WRITEABLE))
 168                 return -EROFS;
 169         if (to >= mtd->size)
 170                 len = 0;
 171         else if (to + len > mtd->size)
 172                 len = mtd->size - to;
 173         return part->master->write_oob (part->master, to + part->offset,
 174                                         len, retlen, buf);
 175 }
 176
 177 static int part_write_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
 178                         size_t *retlen, u_char *buf)
 179 {
 180         struct mtd_part *part = PART(mtd);
 181         return part->master->write_user_prot_reg (part->master, from,
 182                                         len, retlen, buf);
 183 }
 184
 185 static int part_writev (struct mtd_info *mtd,  const struct iovec *vecs,
 186                          unsigned long count, loff_t to, size_t *retlen)
 187 {
 188         struct mtd_part *part = PART(mtd);
 189         if (!(mtd->flags & MTD_WRITEABLE))
 190                 return -EROFS;
 191         if (part->master->writev_ecc == NULL)
 192                 return part->master->writev (part->master, vecs, count,
 193                                         to + part->offset, retlen);
 194         else
 195                 return part->master->writev_ecc (part->master, vecs, count,
 196                                         to + part->offset, retlen,
 197                                         NULL, &mtd->oobinfo);
 198 }
 199
 200 static int part_readv (struct mtd_info *mtd,  struct iovec *vecs,
 201                          unsigned long count, loff_t from, size_t *retlen)
 202 {
 203         struct mtd_part *part = PART(mtd);
 204         if (part->master->readv_ecc == NULL)
 205                 return part->master->readv (part->master, vecs, count,
 206                                         from + part->offset, retlen);
 207         else
 208                 return part->master->readv_ecc (part->master, vecs, count,
 209                                         from + part->offset, retlen,
 210                                         NULL, &mtd->oobinfo);
 211 }
 212
 213 static int part_writev_ecc (struct mtd_info *mtd,  const struct iovec *vecs,
 214                          unsigned long count, loff_t to, size_t *retlen,
 215                          u_char *eccbuf,  struct nand_oobinfo *oobsel)
 216 {
 217         struct mtd_part *part = PART(mtd);
 218         if (!(mtd->flags & MTD_WRITEABLE))
 219                 return -EROFS;
 220         if (oobsel == NULL)
 221                 oobsel = &mtd->oobinfo;
 222         return part->master->writev_ecc (part->master, vecs, count,
 223                                         to + part->offset, retlen,
 224                                         eccbuf, oobsel);
 225 }
 226
 227 static int part_readv_ecc (struct mtd_info *mtd,  struct iovec *vecs,
 228                          unsigned long count, loff_t from, size_t *retlen,
 229                          u_char *eccbuf,  struct nand_oobinfo *oobsel)
 230 {
 231         struct mtd_part *part = PART(mtd);
 232         if (oobsel == NULL)
 233                 oobsel = &mtd->oobinfo;
 234         return part->master->readv_ecc (part->master, vecs, count,
 235                                         from + part->offset, retlen,
 236                                         eccbuf, oobsel);
 237 }
 238
 239 static int part_erase (struct mtd_info *mtd, struct erase_info *instr)
 240 {
 241         struct mtd_part *part = PART(mtd);
 242         if (!(mtd->flags & MTD_WRITEABLE))
 243                 return -EROFS;
 244         if (instr->addr >= mtd->size)
 245                 return -EINVAL;
 246         instr->addr += part->offset;
 247         return part->master->erase(part->master, instr);
 248 }
 249
 250 static int part_lock (struct mtd_info *mtd, loff_t ofs, size_t len)
 251 {
 252         struct mtd_part *part = PART(mtd);
 253         if ((len + ofs) > mtd->size)
 254                 return -EINVAL;
 255         return part->master->lock(part->master, ofs + part->offset, len);
 256 }
 257
 258 static int part_unlock (struct mtd_info *mtd, loff_t ofs, size_t len)
 259 {
 260         struct mtd_part *part = PART(mtd);
 261         if ((len + ofs) > mtd->size)
 262                 return -EINVAL;
 263         return part->master->unlock(part->master, ofs + part->offset, len);
 264 }
 265
 266 static void part_sync(struct mtd_info *mtd)
 267 {
 268         struct mtd_part *part = PART(mtd);
 269         part->master->sync(part->master);
 270 }
 271
 272 static int part_suspend(struct mtd_info *mtd)
 273 {
 274         struct mtd_part *part = PART(mtd);
 275         return part->master->suspend(part->master);
 276 }
 277
 278 static void part_resume(struct mtd_info *mtd)
 279 {
 280         struct mtd_part *part = PART(mtd);
 281         part->master->resume(part->master);
 282 }
 283
 284 /*
 285  * This function unregisters and destroy all slave MTD objects which are
 286  * attached to the given master MTD object.
 287  */
 288
 289 int del_mtd_partitions(struct mtd_info *master)
 290 {
 291         struct list_head *node;
 292         struct mtd_part *slave;
 293
 294         for (node = mtd_partitions.next;
 295              node != &mtd_partitions;
 296              node = node->next) {
 297                 slave = list_entry(node, struct mtd_part, list);
 298                 if (slave->master == master) {
 299                         struct list_head *prev = node->prev;
 300                         __list_del(prev, node->next);
 301                         if(slave->registered)
 302                                 del_mtd_device(&slave->mtd);
 303                         kfree(slave);
 304                         node = prev;
 305                 }
 306         }
 307
 308         return 0;
 309 }
 310
 311 /*
 312  * This function, given a master MTD object and a partition table, creates
 313  * and registers slave MTD objects which are bound to the master according to
 314  * the partition definitions.
 315  * (Q: should we register the master MTD object as well?)
 316  */
 317
 318 int add_mtd_partitions(struct mtd_info *master,
 319                        struct mtd_partition *parts,
 320                        int nbparts)
 321 {
 322         struct mtd_part *slave;
 323         u_int32_t cur_offset = 0;
 324         int i;
 325
 326         printk (KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
 327
 328         for (i = 0; i < nbparts; i++) {
 329
 330                 /* allocate the partition structure */
 331                 slave = kmalloc (sizeof(*slave), GFP_KERNEL);
 332                 if (!slave) {
 333                         printk ("memory allocation error while creating partitions for \"%s\"\n",
 334                                 master->name);
 335                         del_mtd_partitions(master);
 336                         return -ENOMEM;
 337                 }
 338                 memset(slave, 0, sizeof(*slave));
 339                 list_add(&slave->list, &mtd_partitions);
 340
 341                 /* set up the MTD object for this partition */
 342                 slave->mtd.type = master->type;
 343                 slave->mtd.flags = master->flags & ~parts[i].mask_flags;
 344                 slave->mtd.size = parts[i].size;
 345                 slave->mtd.oobblock = master->oobblock;
 346                 slave->mtd.oobsize = master->oobsize;
 347                 slave->mtd.ecctype = master->ecctype;
 348                 slave->mtd.eccsize = master->eccsize;
 349
 350                 slave->mtd.name = parts[i].name;
 351                 slave->mtd.bank_size = master->bank_size;
 352                 slave->mtd.owner = master->owner;
 353
 354                 slave->mtd.read = part_read;
 355                 slave->mtd.write = part_write;
 356
 357                 if(master->point && master->unpoint){
 358                         slave->mtd.point = part_point;
 359                         slave->mtd.unpoint = part_unpoint;
 360                 }
 361
 362                 if (master->read_ecc)
 363                         slave->mtd.read_ecc = part_read_ecc;
 364                 if (master->write_ecc)
 365                         slave->mtd.write_ecc = part_write_ecc;
 366                 if (master->read_oob)
 367                         slave->mtd.read_oob = part_read_oob;
 368                 if (master->write_oob)
 369                         slave->mtd.write_oob = part_write_oob;
 370                 if(master->read_user_prot_reg)
 371                         slave->mtd.read_user_prot_reg = part_read_user_prot_reg;
 372                 if(master->read_fact_prot_reg)
 373                         slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg;
 374                 if(master->write_user_prot_reg)
 375                         slave->mtd.write_user_prot_reg = part_write_user_prot_reg;
 376                 if (master->sync)
 377                         slave->mtd.sync = part_sync;
 378                 if (!i && master->suspend && master->resume) {
 379                                 slave->mtd.suspend = part_suspend;
 380                                 slave->mtd.resume = part_resume;
 381                 }
 382                 if (master->writev)
 383                         slave->mtd.writev = part_writev;
 384                 if (master->readv)
 385                         slave->mtd.readv = part_readv;
 386                 if (master->writev_ecc)
 387                         slave->mtd.writev_ecc = part_writev_ecc;
 388                 if (master->readv_ecc)
 389                         slave->mtd.readv_ecc = part_readv_ecc;
 390                 if (master->lock)
 391                         slave->mtd.lock = part_lock;
 392                 if (master->unlock)
 393                         slave->mtd.unlock = part_unlock;
 394                 slave->mtd.erase = part_erase;
 395                 slave->master = master;
 396                 slave->offset = parts[i].offset;
 397                 slave->index = i;
 398
 399                 if (slave->offset == MTDPART_OFS_APPEND)
 400                         slave->offset = cur_offset;
 401                 if (slave->offset == MTDPART_OFS_NXTBLK) {
 402                         u_int32_t emask = master->erasesize-1;
 403                         slave->offset = (cur_offset + emask) & ~emask;
 404                         if (slave->offset != cur_offset) {
 405                                 printk(KERN_NOTICE "Moving partition %d: "
 406                                        "0x%08x -> 0x%08x\n", i,
 407                                        cur_offset, slave->offset);
 408                         }
 409                 }
 410                 if (slave->mtd.size == MTDPART_SIZ_FULL)
 411                         slave->mtd.size = master->size - slave->offset;
 412                 cur_offset = slave->offset + slave->mtd.size;
 413
 414                 printk (KERN_NOTICE "0x%08x-0x%08x : \"%s\"\n", slave->offset,
 415                         slave->offset + slave->mtd.size, slave->mtd.name);
 416
 417                 /* let's do some sanity checks */
 418                 if (slave->offset >= master->size) {
 419                                 /* let's register it anyway to preserve ordering */
 420                         slave->offset = 0;
 421                         slave->mtd.size = 0;
 422                         printk ("mtd: partition \"%s\" is out of reach -- disabled\n",
 423                                 parts[i].name);
 424                 }
 425                 if (slave->offset + slave->mtd.size > master->size) {
 426                         slave->mtd.size = master->size - slave->offset;
 427                         printk ("mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#x\n",
 428                                 parts[i].name, master->name, slave->mtd.size);
 429                 }
 430                 if (master->numeraseregions>1) {
 431                         /* Deal with variable erase size stuff */
 432                         int i;
 433                         struct mtd_erase_region_info *regions = master->eraseregions;
 434
 435                         /* Find the first erase regions which is part of this partition. */
 436                         for (i=0; i < master->numeraseregions && slave->offset >= regions[i].offset; i++)
 437                                 ;
 438
 439                         for (i--; i < master->numeraseregions && slave->offset + slave->mtd.size > regions[i].offset; i++) {
 440                                 if (slave->mtd.erasesize < regions[i].erasesize) {
 441                                         slave->mtd.erasesize = regions[i].erasesize;
 442                                 }
 443                         }
 444                 } else {
 445                         /* Single erase size */
 446                         slave->mtd.erasesize = master->erasesize;
 447                 }
 448
 449                 if ((slave->mtd.flags & MTD_WRITEABLE) &&
 450                     (slave->offset % slave->mtd.erasesize)) {
 451                         /* Doesn't start on a boundary of major erase size */
 452                         /* FIXME: Let it be writable if it is on a boundary of _minor_ erase size though */
 453                         slave->mtd.flags &= ~MTD_WRITEABLE;
 454                         printk ("mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
 455                                 parts[i].name);
 456                 }
 457                 if ((slave->mtd.flags & MTD_WRITEABLE) &&
 458                     (slave->mtd.size % slave->mtd.erasesize)) {
 459                         slave->mtd.flags &= ~MTD_WRITEABLE;
 460                         printk ("mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
 461                                 parts[i].name);
 462                 }
 463
 464                 if(parts[i].mtdp)
 465                 {       /* store the object pointer (caller may or may not register it */
 466                         *parts[i].mtdp = &slave->mtd;
 467                         slave->registered = 0;
 468                 }
 469                 else
 470                 {
 471                         /* register our partition */
 472                         add_mtd_device(&slave->mtd);
 473                         slave->registered = 1;
 474                 }
 475         }
 476
 477         return 0;
 478 }
 479
 480 EXPORT_SYMBOL(add_mtd_partitions);
 481 EXPORT_SYMBOL(del_mtd_partitions);
 482
 483 static spinlock_t part_parser_lock = SPIN_LOCK_UNLOCKED;
 484 static LIST_HEAD(part_parsers);
 485
 486 struct mtd_part_parser *get_partition_parser(const char *name)
 487 {
 488         struct list_head *this;
 489         void *ret = NULL;
 490         spin_lock(&part_parser_lock);
 491
 492         list_for_each(this, &part_parsers) {
 493                 struct mtd_part_parser *p = list_entry(this, struct mtd_part_parser, list);
 494
 495                 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
 496                         ret = p;
 497                         break;
 498                 }
 499         }
 500         spin_unlock(&part_parser_lock);
 501
 502         return ret;
 503 }
 504
 505 int register_mtd_parser(struct mtd_part_parser *p)
 506 {
 507         spin_lock(&part_parser_lock);
 508         list_add(&p->list, &part_parsers);
 509         spin_unlock(&part_parser_lock);
 510
 511         return 0;
 512 }
 513
 514 int deregister_mtd_parser(struct mtd_part_parser *p)
 515 {
 516         spin_lock(&part_parser_lock);
 517         list_del(&p->list);
 518         spin_unlock(&part_parser_lock);
 519         return 0;
 520 }
 521
 522 int parse_mtd_partitions(struct mtd_info *master, const char **types,
 523                          struct mtd_partition **pparts, unsigned long origin)
 524 {
 525         struct mtd_part_parser *parser;
 526         int ret = 0;
 527
 528         for ( ; ret <= 0 && *types; types++) {
 529                 parser = get_partition_parser(*types);
 530 #ifdef CONFIG_KMOD
 531                 if (!parser && !request_module("%s", *types))
 532                                 parser = get_partition_parser(*types);
 533 #endif
 534                 if (!parser) {
 535                         printk(KERN_NOTICE "%s partition parsing not available\n",
 536                                *types);
 537                         continue;
 538                 }
 539                 ret = (*parser->parse_fn)(master, pparts, origin);
 540                 if (ret > 0) {
 541                         printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
 542                                ret, parser->name, master->name);
 543                 }
 544                 put_partition_parser(parser);
 545         }
 546         return ret;
 547 }
 548
 549 EXPORT_SYMBOL_GPL(parse_mtd_partitions);
 550 EXPORT_SYMBOL_GPL(register_mtd_parser);
 551 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
 552
 553 MODULE_LICENSE("GPL");
 554 MODULE_AUTHOR("Nicolas Pitre <nico@cam.org>");
 555 MODULE_DESCRIPTION("Generic support for partitioning of MTD devices");
 556