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  *      02-21-2002      Thomas Gleixner <gleixner@autronix.de>
   9  *                      added support for read_oob, write_oob
  10  */
  11
  12 #include <common.h>
  13 #include <malloc.h>
  14 #include <asm/errno.h>
  15
  16 #include <linux/types.h>
  17 #include <linux/list.h>
  18 #include <linux/mtd/mtd.h>
  19 #include <linux/mtd/partitions.h>
  20 #include <linux/compat.h>
  21
  22 /* Our partition linked list */
  23 struct list_head mtd_partitions;
  24
  25 /* Our partition node structure */
  26 struct mtd_part {
  27         struct mtd_info mtd;
  28         struct mtd_info *master;
  29         uint64_t offset;
  30         int index;
  31         struct list_head list;
  32         int registered;
  33 };
  34
  35 /*
  36  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
  37  * the pointer to that structure with this macro.
  38  */
  39 #define PART(x)  ((struct mtd_part *)(x))
  40
  41
  42 /*
  43  * MTD methods which simply translate the effective address and pass through
  44  * to the _real_ device.
  45  */
  46
  47 static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
  48                 size_t *retlen, u_char *buf)
  49 {
  50         struct mtd_part *part = PART(mtd);
  51         struct mtd_ecc_stats stats;
  52         int res;
  53
  54         stats = part->master->ecc_stats;
  55         res = mtd_read(part->master, from + part->offset, len, retlen, buf);
  56         if (unlikely(mtd_is_eccerr(res)))
  57                 mtd->ecc_stats.failed +=
  58                         part->master->ecc_stats.failed - stats.failed;
  59         else
  60                 mtd->ecc_stats.corrected +=
  61                         part->master->ecc_stats.corrected - stats.corrected;
  62         return res;
  63 }
  64
  65 static int part_read_oob(struct mtd_info *mtd, loff_t from,
  66                 struct mtd_oob_ops *ops)
  67 {
  68         struct mtd_part *part = PART(mtd);
  69         int res;
  70
  71         if (from >= mtd->size)
  72                 return -EINVAL;
  73         if (ops->datbuf && from + ops->len > mtd->size)
  74                 return -EINVAL;
  75         res = mtd_read_oob(part->master, from + part->offset, ops);
  76
  77         if (unlikely(res)) {
  78                 if (mtd_is_bitflip(res))
  79                         mtd->ecc_stats.corrected++;
  80                 if (mtd_is_eccerr(res))
  81                         mtd->ecc_stats.failed++;
  82         }
  83         return res;
  84 }
  85
  86 static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
  87                 size_t len, size_t *retlen, u_char *buf)
  88 {
  89         struct mtd_part *part = PART(mtd);
  90         return mtd_read_user_prot_reg(part->master, from, len, retlen, buf);
  91 }
  92
  93 static int part_get_user_prot_info(struct mtd_info *mtd,
  94                 struct otp_info *buf, size_t len)
  95 {
  96         struct mtd_part *part = PART(mtd);
  97         return mtd_get_user_prot_info(part->master, buf, len);
  98 }
  99
 100 static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
 101                 size_t len, size_t *retlen, u_char *buf)
 102 {
 103         struct mtd_part *part = PART(mtd);
 104         return mtd_read_fact_prot_reg(part->master, from, len, retlen, buf);
 105 }
 106
 107 static int part_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
 108                 size_t len)
 109 {
 110         struct mtd_part *part = PART(mtd);
 111         return mtd_get_fact_prot_info(part->master, buf, len);
 112 }
 113
 114 static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
 115                 size_t *retlen, const u_char *buf)
 116 {
 117         struct mtd_part *part = PART(mtd);
 118         return mtd_write(part->master, to + part->offset, len, retlen, buf);
 119 }
 120
 121 static int part_write_oob(struct mtd_info *mtd, loff_t to,
 122                 struct mtd_oob_ops *ops)
 123 {
 124         struct mtd_part *part = PART(mtd);
 125
 126         if (to >= mtd->size)
 127                 return -EINVAL;
 128         if (ops->datbuf && to + ops->len > mtd->size)
 129                 return -EINVAL;
 130         return mtd_write_oob(part->master, to + part->offset, ops);
 131 }
 132
 133 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
 134                 size_t len, size_t *retlen, u_char *buf)
 135 {
 136         struct mtd_part *part = PART(mtd);
 137         return mtd_write_user_prot_reg(part->master, from, len, retlen, buf);
 138 }
 139
 140 static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
 141                 size_t len)
 142 {
 143         struct mtd_part *part = PART(mtd);
 144         return mtd_lock_user_prot_reg(part->master, from, len);
 145 }
 146
 147 static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
 148 {
 149         struct mtd_part *part = PART(mtd);
 150         int ret;
 151
 152         instr->addr += part->offset;
 153         ret = mtd_erase(part->master, instr);
 154         if (ret) {
 155                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 156                         instr->fail_addr -= part->offset;
 157                 instr->addr -= part->offset;
 158         }
 159         return ret;
 160 }
 161
 162 void mtd_erase_callback(struct erase_info *instr)
 163 {
 164         if (instr->mtd->_erase == part_erase) {
 165                 struct mtd_part *part = PART(instr->mtd);
 166
 167                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 168                         instr->fail_addr -= part->offset;
 169                 instr->addr -= part->offset;
 170         }
 171         if (instr->callback)
 172                 instr->callback(instr);
 173 }
 174
 175 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 176 {
 177         struct mtd_part *part = PART(mtd);
 178         return mtd_lock(part->master, ofs + part->offset, len);
 179 }
 180
 181 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 182 {
 183         struct mtd_part *part = PART(mtd);
 184         return mtd_unlock(part->master, ofs + part->offset, len);
 185 }
 186
 187 static void part_sync(struct mtd_info *mtd)
 188 {
 189         struct mtd_part *part = PART(mtd);
 190         mtd_sync(part->master);
 191 }
 192
 193 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
 194 {
 195         struct mtd_part *part = PART(mtd);
 196         ofs += part->offset;
 197         return mtd_block_isbad(part->master, ofs);
 198 }
 199
 200 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
 201 {
 202         struct mtd_part *part = PART(mtd);
 203         int res;
 204
 205         ofs += part->offset;
 206         res = mtd_block_markbad(part->master, ofs);
 207         if (!res)
 208                 mtd->ecc_stats.badblocks++;
 209         return res;
 210 }
 211
 212 /*
 213  * This function unregisters and destroy all slave MTD objects which are
 214  * attached to the given master MTD object.
 215  */
 216
 217 int del_mtd_partitions(struct mtd_info *master)
 218 {
 219         struct mtd_part *slave, *next;
 220
 221         list_for_each_entry_safe(slave, next, &mtd_partitions, list)
 222                 if (slave->master == master) {
 223                         list_del(&slave->list);
 224                         if (slave->registered)
 225                                 del_mtd_device(&slave->mtd);
 226                         kfree(slave);
 227                 }
 228
 229         return 0;
 230 }
 231
 232 static struct mtd_part *add_one_partition(struct mtd_info *master,
 233                 const struct mtd_partition *part, int partno,
 234                 uint64_t cur_offset)
 235 {
 236         struct mtd_part *slave;
 237
 238         /* allocate the partition structure */
 239         slave = kzalloc(sizeof(*slave), GFP_KERNEL);
 240         if (!slave) {
 241                 printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
 242                         master->name);
 243                 del_mtd_partitions(master);
 244                 return NULL;
 245         }
 246         list_add(&slave->list, &mtd_partitions);
 247
 248         /* set up the MTD object for this partition */
 249         slave->mtd.type = master->type;
 250         slave->mtd.flags = master->flags & ~part->mask_flags;
 251         slave->mtd.size = part->size;
 252         slave->mtd.writesize = master->writesize;
 253         slave->mtd.oobsize = master->oobsize;
 254         slave->mtd.oobavail = master->oobavail;
 255         slave->mtd.subpage_sft = master->subpage_sft;
 256
 257         slave->mtd.name = part->name;
 258         slave->mtd.owner = master->owner;
 259
 260         slave->mtd._read = part_read;
 261         slave->mtd._write = part_write;
 262
 263         if (master->_read_oob)
 264                 slave->mtd._read_oob = part_read_oob;
 265         if (master->_write_oob)
 266                 slave->mtd._write_oob = part_write_oob;
 267         if (master->_read_user_prot_reg)
 268                 slave->mtd._read_user_prot_reg = part_read_user_prot_reg;
 269         if (master->_read_fact_prot_reg)
 270                 slave->mtd._read_fact_prot_reg = part_read_fact_prot_reg;
 271         if (master->_write_user_prot_reg)
 272                 slave->mtd._write_user_prot_reg = part_write_user_prot_reg;
 273         if (master->_lock_user_prot_reg)
 274                 slave->mtd._lock_user_prot_reg = part_lock_user_prot_reg;
 275         if (master->_get_user_prot_info)
 276                 slave->mtd._get_user_prot_info = part_get_user_prot_info;
 277         if (master->_get_fact_prot_info)
 278                 slave->mtd._get_fact_prot_info = part_get_fact_prot_info;
 279         if (master->_sync)
 280                 slave->mtd._sync = part_sync;
 281         if (master->_lock)
 282                 slave->mtd._lock = part_lock;
 283         if (master->_unlock)
 284                 slave->mtd._unlock = part_unlock;
 285         if (master->_block_isbad)
 286                 slave->mtd._block_isbad = part_block_isbad;
 287         if (master->_block_markbad)
 288                 slave->mtd._block_markbad = part_block_markbad;
 289         slave->mtd._erase = part_erase;
 290         slave->master = master;
 291         slave->offset = part->offset;
 292         slave->index = partno;
 293
 294         if (slave->offset == MTDPART_OFS_APPEND)
 295                 slave->offset = cur_offset;
 296         if (slave->offset == MTDPART_OFS_NXTBLK) {
 297                 slave->offset = cur_offset;
 298                 if (mtd_mod_by_eb(cur_offset, master) != 0) {
 299                         /* Round up to next erasesize */
 300                         slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
 301                         debug("Moving partition %d: 0x%012llx -> 0x%012llx\n",
 302                               partno, (unsigned long long)cur_offset,
 303                               (unsigned long long)slave->offset);
 304                 }
 305         }
 306         if (slave->mtd.size == MTDPART_SIZ_FULL)
 307                 slave->mtd.size = master->size - slave->offset;
 308
 309         debug("0x%012llx-0x%012llx : \"%s\"\n",
 310               (unsigned long long)slave->offset,
 311               (unsigned long long)(slave->offset + slave->mtd.size),
 312               slave->mtd.name);
 313
 314         /* let's do some sanity checks */
 315         if (slave->offset >= master->size) {
 316                 /* let's register it anyway to preserve ordering */
 317                 slave->offset = 0;
 318                 slave->mtd.size = 0;
 319                 printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
 320                         part->name);
 321                 goto out_register;
 322         }
 323         if (slave->offset + slave->mtd.size > master->size) {
 324                 slave->mtd.size = master->size - slave->offset;
 325                 printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
 326                         part->name, master->name, (unsigned long long)slave->mtd.size);
 327         }
 328         if (master->numeraseregions > 1) {
 329                 /* Deal with variable erase size stuff */
 330                 int i, max = master->numeraseregions;
 331                 u64 end = slave->offset + slave->mtd.size;
 332                 struct mtd_erase_region_info *regions = master->eraseregions;
 333
 334                 /* Find the first erase regions which is part of this
 335                  * partition. */
 336                 for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
 337                         ;
 338                 /* The loop searched for the region _behind_ the first one */
 339                 i--;
 340
 341                 /* Pick biggest erasesize */
 342                 for (; i < max && regions[i].offset < end; i++) {
 343                         if (slave->mtd.erasesize < regions[i].erasesize) {
 344                                 slave->mtd.erasesize = regions[i].erasesize;
 345                         }
 346                 }
 347                 BUG_ON(slave->mtd.erasesize == 0);
 348         } else {
 349                 /* Single erase size */
 350                 slave->mtd.erasesize = master->erasesize;
 351         }
 352
 353         if ((slave->mtd.flags & MTD_WRITEABLE) &&
 354             mtd_mod_by_eb(slave->offset, &slave->mtd)) {
 355                 /* Doesn't start on a boundary of major erase size */
 356                 /* FIXME: Let it be writable if it is on a boundary of
 357                  * _minor_ erase size though */
 358                 slave->mtd.flags &= ~MTD_WRITEABLE;
 359                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
 360                         part->name);
 361         }
 362         if ((slave->mtd.flags & MTD_WRITEABLE) &&
 363             mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
 364                 slave->mtd.flags &= ~MTD_WRITEABLE;
 365                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
 366                         part->name);
 367         }
 368
 369         slave->mtd.ecclayout = master->ecclayout;
 370         if (master->_block_isbad) {
 371                 uint64_t offs = 0;
 372
 373                 while (offs < slave->mtd.size) {
 374                         if (mtd_block_isbad(master, offs + slave->offset))
 375                                 slave->mtd.ecc_stats.badblocks++;
 376                         offs += slave->mtd.erasesize;
 377                 }
 378         }
 379
 380 out_register:
 381         if (part->mtdp) {
 382                 /* store the object pointer (caller may or may not register it*/
 383                 *part->mtdp = &slave->mtd;
 384                 slave->registered = 0;
 385         } else {
 386                 /* register our partition */
 387                 add_mtd_device(&slave->mtd);
 388                 slave->registered = 1;
 389         }
 390         return slave;
 391 }
 392
 393 /*
 394  * This function, given a master MTD object and a partition table, creates
 395  * and registers slave MTD objects which are bound to the master according to
 396  * the partition definitions.
 397  *
 398  * We don't register the master, or expect the caller to have done so,
 399  * for reasons of data integrity.
 400  */
 401
 402 int add_mtd_partitions(struct mtd_info *master,
 403                        const struct mtd_partition *parts,
 404                        int nbparts)
 405 {
 406         struct mtd_part *slave;
 407         uint64_t cur_offset = 0;
 408         int i;
 409
 410         /*
 411          * Need to init the list here, since LIST_INIT() does not
 412          * work on platforms where relocation has problems (like MIPS
 413          * & PPC).
 414          */
 415         if (mtd_partitions.next == NULL)
 416                 INIT_LIST_HEAD(&mtd_partitions);
 417
 418         debug("Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
 419
 420         for (i = 0; i < nbparts; i++) {
 421                 slave = add_one_partition(master, parts + i, i, cur_offset);
 422                 if (!slave)
 423                         return -ENOMEM;
 424                 cur_offset = slave->offset + slave->mtd.size;
 425         }
 426
 427         return 0;
 428 }