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 1.55 2005/11/07 11:14:20 gleixner 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         return part->master->read (part->master, from + part->offset,
  59                                    len, retlen, buf);
  60 }
  61
  62 static int part_point (struct mtd_info *mtd, loff_t from, size_t len,
  63                         size_t *retlen, u_char **buf)
  64 {
  65         struct mtd_part *part = PART(mtd);
  66         if (from >= mtd->size)
  67                 len = 0;
  68         else if (from + len > mtd->size)
  69                 len = mtd->size - from;
  70         return part->master->point (part->master, from + part->offset,
  71                                     len, retlen, buf);
  72 }
  73
  74 static void part_unpoint (struct mtd_info *mtd, u_char *addr, loff_t from, size_t len)
  75 {
  76         struct mtd_part *part = PART(mtd);
  77
  78         part->master->unpoint (part->master, addr, from + part->offset, len);
  79 }
  80
  81 static int part_read_oob (struct mtd_info *mtd, loff_t from, size_t len,
  82                         size_t *retlen, u_char *buf)
  83 {
  84         struct mtd_part *part = PART(mtd);
  85         if (from >= mtd->size)
  86                 len = 0;
  87         else if (from + len > mtd->size)
  88                 len = mtd->size - from;
  89         return part->master->read_oob (part->master, from + part->offset,
  90                                         len, retlen, buf);
  91 }
  92
  93 static int part_read_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
  94                         size_t *retlen, u_char *buf)
  95 {
  96         struct mtd_part *part = PART(mtd);
  97         return part->master->read_user_prot_reg (part->master, from,
  98                                         len, retlen, buf);
  99 }
 100
 101 static int part_get_user_prot_info (struct mtd_info *mtd,
 102                                     struct otp_info *buf, size_t len)
 103 {
 104         struct mtd_part *part = PART(mtd);
 105         return part->master->get_user_prot_info (part->master, buf, len);
 106 }
 107
 108 static int part_read_fact_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
 109                         size_t *retlen, u_char *buf)
 110 {
 111         struct mtd_part *part = PART(mtd);
 112         return part->master->read_fact_prot_reg (part->master, from,
 113                                         len, retlen, buf);
 114 }
 115
 116 static int part_get_fact_prot_info (struct mtd_info *mtd,
 117                                     struct otp_info *buf, size_t len)
 118 {
 119         struct mtd_part *part = PART(mtd);
 120         return part->master->get_fact_prot_info (part->master, buf, len);
 121 }
 122
 123 static int part_write (struct mtd_info *mtd, loff_t to, size_t len,
 124                         size_t *retlen, const u_char *buf)
 125 {
 126         struct mtd_part *part = PART(mtd);
 127         if (!(mtd->flags & MTD_WRITEABLE))
 128                 return -EROFS;
 129         if (to >= mtd->size)
 130                 len = 0;
 131         else if (to + len > mtd->size)
 132                 len = mtd->size - to;
 133         return part->master->write (part->master, to + part->offset,
 134                                     len, retlen, buf);
 135 }
 136
 137 static int part_write_oob (struct mtd_info *mtd, loff_t to, size_t len,
 138                         size_t *retlen, const u_char *buf)
 139 {
 140         struct mtd_part *part = PART(mtd);
 141         if (!(mtd->flags & MTD_WRITEABLE))
 142                 return -EROFS;
 143         if (to >= mtd->size)
 144                 len = 0;
 145         else if (to + len > mtd->size)
 146                 len = mtd->size - to;
 147         return part->master->write_oob (part->master, to + part->offset,
 148                                         len, retlen, buf);
 149 }
 150
 151 static int part_write_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
 152                         size_t *retlen, u_char *buf)
 153 {
 154         struct mtd_part *part = PART(mtd);
 155         return part->master->write_user_prot_reg (part->master, from,
 156                                         len, retlen, buf);
 157 }
 158
 159 static int part_lock_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len)
 160 {
 161         struct mtd_part *part = PART(mtd);
 162         return part->master->lock_user_prot_reg (part->master, from, len);
 163 }
 164
 165 static int part_writev (struct mtd_info *mtd,  const struct kvec *vecs,
 166                          unsigned long count, loff_t to, size_t *retlen)
 167 {
 168         struct mtd_part *part = PART(mtd);
 169         if (!(mtd->flags & MTD_WRITEABLE))
 170                 return -EROFS;
 171         return part->master->writev (part->master, vecs, count,
 172                                         to + part->offset, retlen);
 173 }
 174
 175 static int part_erase (struct mtd_info *mtd, struct erase_info *instr)
 176 {
 177         struct mtd_part *part = PART(mtd);
 178         int ret;
 179         if (!(mtd->flags & MTD_WRITEABLE))
 180                 return -EROFS;
 181         if (instr->addr >= mtd->size)
 182                 return -EINVAL;
 183         instr->addr += part->offset;
 184         ret = part->master->erase(part->master, instr);
 185         return ret;
 186 }
 187
 188 void mtd_erase_callback(struct erase_info *instr)
 189 {
 190         if (instr->mtd->erase == part_erase) {
 191                 struct mtd_part *part = PART(instr->mtd);
 192
 193                 if (instr->fail_addr != 0xffffffff)
 194                         instr->fail_addr -= part->offset;
 195                 instr->addr -= part->offset;
 196         }
 197         if (instr->callback)
 198                 instr->callback(instr);
 199 }
 200 EXPORT_SYMBOL_GPL(mtd_erase_callback);
 201
 202 static int part_lock (struct mtd_info *mtd, loff_t ofs, size_t len)
 203 {
 204         struct mtd_part *part = PART(mtd);
 205         if ((len + ofs) > mtd->size)
 206                 return -EINVAL;
 207         return part->master->lock(part->master, ofs + part->offset, len);
 208 }
 209
 210 static int part_unlock (struct mtd_info *mtd, loff_t ofs, size_t len)
 211 {
 212         struct mtd_part *part = PART(mtd);
 213         if ((len + ofs) > mtd->size)
 214                 return -EINVAL;
 215         return part->master->unlock(part->master, ofs + part->offset, len);
 216 }
 217
 218 static void part_sync(struct mtd_info *mtd)
 219 {
 220         struct mtd_part *part = PART(mtd);
 221         part->master->sync(part->master);
 222 }
 223
 224 static int part_suspend(struct mtd_info *mtd)
 225 {
 226         struct mtd_part *part = PART(mtd);
 227         return part->master->suspend(part->master);
 228 }
 229
 230 static void part_resume(struct mtd_info *mtd)
 231 {
 232         struct mtd_part *part = PART(mtd);
 233         part->master->resume(part->master);
 234 }
 235
 236 static int part_block_isbad (struct mtd_info *mtd, loff_t ofs)
 237 {
 238         struct mtd_part *part = PART(mtd);
 239         if (ofs >= mtd->size)
 240                 return -EINVAL;
 241         ofs += part->offset;
 242         return part->master->block_isbad(part->master, ofs);
 243 }
 244
 245 static int part_block_markbad (struct mtd_info *mtd, loff_t ofs)
 246 {
 247         struct mtd_part *part = PART(mtd);
 248         if (!(mtd->flags & MTD_WRITEABLE))
 249                 return -EROFS;
 250         if (ofs >= mtd->size)
 251                 return -EINVAL;
 252         ofs += part->offset;
 253         return part->master->block_markbad(part->master, ofs);
 254 }
 255
 256 /*
 257  * This function unregisters and destroy all slave MTD objects which are
 258  * attached to the given master MTD object.
 259  */
 260
 261 int del_mtd_partitions(struct mtd_info *master)
 262 {
 263         struct list_head *node;
 264         struct mtd_part *slave;
 265
 266         for (node = mtd_partitions.next;
 267              node != &mtd_partitions;
 268              node = node->next) {
 269                 slave = list_entry(node, struct mtd_part, list);
 270                 if (slave->master == master) {
 271                         struct list_head *prev = node->prev;
 272                         __list_del(prev, node->next);
 273                         if(slave->registered)
 274                                 del_mtd_device(&slave->mtd);
 275                         kfree(slave);
 276                         node = prev;
 277                 }
 278         }
 279
 280         return 0;
 281 }
 282
 283 /*
 284  * This function, given a master MTD object and a partition table, creates
 285  * and registers slave MTD objects which are bound to the master according to
 286  * the partition definitions.
 287  * (Q: should we register the master MTD object as well?)
 288  */
 289
 290 int add_mtd_partitions(struct mtd_info *master,
 291                        const struct mtd_partition *parts,
 292                        int nbparts)
 293 {
 294         struct mtd_part *slave;
 295         u_int32_t cur_offset = 0;
 296         int i;
 297
 298         printk (KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
 299
 300         for (i = 0; i < nbparts; i++) {
 301
 302                 /* allocate the partition structure */
 303                 slave = kmalloc (sizeof(*slave), GFP_KERNEL);
 304                 if (!slave) {
 305                         printk ("memory allocation error while creating partitions for \"%s\"\n",
 306                                 master->name);
 307                         del_mtd_partitions(master);
 308                         return -ENOMEM;
 309                 }
 310                 memset(slave, 0, sizeof(*slave));
 311                 list_add(&slave->list, &mtd_partitions);
 312
 313                 /* set up the MTD object for this partition */
 314                 slave->mtd.type = master->type;
 315                 slave->mtd.flags = master->flags & ~parts[i].mask_flags;
 316                 slave->mtd.size = parts[i].size;
 317                 slave->mtd.writesize = master->writesize;
 318                 slave->mtd.oobsize = master->oobsize;
 319                 slave->mtd.oobavail = master->oobavail;
 320                 slave->mtd.ecctype = master->ecctype;
 321                 slave->mtd.eccsize = master->eccsize;
 322
 323                 slave->mtd.name = parts[i].name;
 324                 slave->mtd.bank_size = master->bank_size;
 325                 slave->mtd.owner = master->owner;
 326
 327                 slave->mtd.read = part_read;
 328                 slave->mtd.write = part_write;
 329
 330                 if(master->point && master->unpoint){
 331                         slave->mtd.point = part_point;
 332                         slave->mtd.unpoint = part_unpoint;
 333                 }
 334
 335                 if (master->read_oob)
 336                         slave->mtd.read_oob = part_read_oob;
 337                 if (master->write_oob)
 338                         slave->mtd.write_oob = part_write_oob;
 339                 if(master->read_user_prot_reg)
 340                         slave->mtd.read_user_prot_reg = part_read_user_prot_reg;
 341                 if(master->read_fact_prot_reg)
 342                         slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg;
 343                 if(master->write_user_prot_reg)
 344                         slave->mtd.write_user_prot_reg = part_write_user_prot_reg;
 345                 if(master->lock_user_prot_reg)
 346                         slave->mtd.lock_user_prot_reg = part_lock_user_prot_reg;
 347                 if(master->get_user_prot_info)
 348                         slave->mtd.get_user_prot_info = part_get_user_prot_info;
 349                 if(master->get_fact_prot_info)
 350                         slave->mtd.get_fact_prot_info = part_get_fact_prot_info;
 351                 if (master->sync)
 352                         slave->mtd.sync = part_sync;
 353                 if (!i && master->suspend && master->resume) {
 354                                 slave->mtd.suspend = part_suspend;
 355                                 slave->mtd.resume = part_resume;
 356                 }
 357                 if (master->writev)
 358                         slave->mtd.writev = part_writev;
 359                 if (master->lock)
 360                         slave->mtd.lock = part_lock;
 361                 if (master->unlock)
 362                         slave->mtd.unlock = part_unlock;
 363                 if (master->block_isbad)
 364                         slave->mtd.block_isbad = part_block_isbad;
 365                 if (master->block_markbad)
 366                         slave->mtd.block_markbad = part_block_markbad;
 367                 slave->mtd.erase = part_erase;
 368                 slave->master = master;
 369                 slave->offset = parts[i].offset;
 370                 slave->index = i;
 371
 372                 if (slave->offset == MTDPART_OFS_APPEND)
 373                         slave->offset = cur_offset;
 374                 if (slave->offset == MTDPART_OFS_NXTBLK) {
 375                         slave->offset = cur_offset;
 376                         if ((cur_offset % master->erasesize) != 0) {
 377                                 /* Round up to next erasesize */
 378                                 slave->offset = ((cur_offset / master->erasesize) + 1) * master->erasesize;
 379                                 printk(KERN_NOTICE "Moving partition %d: "
 380                                        "0x%08x -> 0x%08x\n", i,
 381                                        cur_offset, slave->offset);
 382                         }
 383                 }
 384                 if (slave->mtd.size == MTDPART_SIZ_FULL)
 385                         slave->mtd.size = master->size - slave->offset;
 386                 cur_offset = slave->offset + slave->mtd.size;
 387
 388                 printk (KERN_NOTICE "0x%08x-0x%08x : \"%s\"\n", slave->offset,
 389                         slave->offset + slave->mtd.size, slave->mtd.name);
 390
 391                 /* let's do some sanity checks */
 392                 if (slave->offset >= master->size) {
 393                                 /* let's register it anyway to preserve ordering */
 394                         slave->offset = 0;
 395                         slave->mtd.size = 0;
 396                         printk ("mtd: partition \"%s\" is out of reach -- disabled\n",
 397                                 parts[i].name);
 398                 }
 399                 if (slave->offset + slave->mtd.size > master->size) {
 400                         slave->mtd.size = master->size - slave->offset;
 401                         printk ("mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#x\n",
 402                                 parts[i].name, master->name, slave->mtd.size);
 403                 }
 404                 if (master->numeraseregions>1) {
 405                         /* Deal with variable erase size stuff */
 406                         int i;
 407                         struct mtd_erase_region_info *regions = master->eraseregions;
 408
 409                         /* Find the first erase regions which is part of this partition. */
 410                         for (i=0; i < master->numeraseregions && slave->offset >= regions[i].offset; i++)
 411                                 ;
 412
 413                         for (i--; i < master->numeraseregions && slave->offset + slave->mtd.size > regions[i].offset; i++) {
 414                                 if (slave->mtd.erasesize < regions[i].erasesize) {
 415                                         slave->mtd.erasesize = regions[i].erasesize;
 416                                 }
 417                         }
 418                 } else {
 419                         /* Single erase size */
 420                         slave->mtd.erasesize = master->erasesize;
 421                 }
 422
 423                 if ((slave->mtd.flags & MTD_WRITEABLE) &&
 424                     (slave->offset % slave->mtd.erasesize)) {
 425                         /* Doesn't start on a boundary of major erase size */
 426                         /* FIXME: Let it be writable if it is on a boundary of _minor_ erase size though */
 427                         slave->mtd.flags &= ~MTD_WRITEABLE;
 428                         printk ("mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
 429                                 parts[i].name);
 430                 }
 431                 if ((slave->mtd.flags & MTD_WRITEABLE) &&
 432                     (slave->mtd.size % slave->mtd.erasesize)) {
 433                         slave->mtd.flags &= ~MTD_WRITEABLE;
 434                         printk ("mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
 435                                 parts[i].name);
 436                 }
 437
 438                 /* copy oobinfo from master */
 439                 memcpy(&slave->mtd.oobinfo, &master->oobinfo, sizeof(slave->mtd.oobinfo));
 440
 441                 if(parts[i].mtdp)
 442                 {       /* store the object pointer (caller may or may not register it */
 443                         *parts[i].mtdp = &slave->mtd;
 444                         slave->registered = 0;
 445                 }
 446                 else
 447                 {
 448                         /* register our partition */
 449                         add_mtd_device(&slave->mtd);
 450                         slave->registered = 1;
 451                 }
 452         }
 453
 454         return 0;
 455 }
 456
 457 EXPORT_SYMBOL(add_mtd_partitions);
 458 EXPORT_SYMBOL(del_mtd_partitions);
 459
 460 static DEFINE_SPINLOCK(part_parser_lock);
 461 static LIST_HEAD(part_parsers);
 462
 463 static struct mtd_part_parser *get_partition_parser(const char *name)
 464 {
 465         struct list_head *this;
 466         void *ret = NULL;
 467         spin_lock(&part_parser_lock);
 468
 469         list_for_each(this, &part_parsers) {
 470                 struct mtd_part_parser *p = list_entry(this, struct mtd_part_parser, list);
 471
 472                 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
 473                         ret = p;
 474                         break;
 475                 }
 476         }
 477         spin_unlock(&part_parser_lock);
 478
 479         return ret;
 480 }
 481
 482 int register_mtd_parser(struct mtd_part_parser *p)
 483 {
 484         spin_lock(&part_parser_lock);
 485         list_add(&p->list, &part_parsers);
 486         spin_unlock(&part_parser_lock);
 487
 488         return 0;
 489 }
 490
 491 int deregister_mtd_parser(struct mtd_part_parser *p)
 492 {
 493         spin_lock(&part_parser_lock);
 494         list_del(&p->list);
 495         spin_unlock(&part_parser_lock);
 496         return 0;
 497 }
 498
 499 int parse_mtd_partitions(struct mtd_info *master, const char **types,
 500                          struct mtd_partition **pparts, unsigned long origin)
 501 {
 502         struct mtd_part_parser *parser;
 503         int ret = 0;
 504
 505         for ( ; ret <= 0 && *types; types++) {
 506                 parser = get_partition_parser(*types);
 507 #ifdef CONFIG_KMOD
 508                 if (!parser && !request_module("%s", *types))
 509                                 parser = get_partition_parser(*types);
 510 #endif
 511                 if (!parser) {
 512                         printk(KERN_NOTICE "%s partition parsing not available\n",
 513                                *types);
 514                         continue;
 515                 }
 516                 ret = (*parser->parse_fn)(master, pparts, origin);
 517                 if (ret > 0) {
 518                         printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
 519                                ret, parser->name, master->name);
 520                 }
 521                 put_partition_parser(parser);
 522         }
 523         return ret;
 524 }
 525
 526 EXPORT_SYMBOL_GPL(parse_mtd_partitions);
 527 EXPORT_SYMBOL_GPL(register_mtd_parser);
 528 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
 529
 530 MODULE_LICENSE("GPL");
 531 MODULE_AUTHOR("Nicolas Pitre <nico@cam.org>");
 532 MODULE_DESCRIPTION("Generic support for partitioning of MTD devices");
 533