include/linux/mtd/mtd.h

   1 /*
   2  * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> et al.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  *
  18  */
  19
  20 #ifndef __MTD_MTD_H__
  21 #define __MTD_MTD_H__
  22
  23 #include <linux/types.h>
  24 #include <linux/uio.h>
  25 #include <linux/notifier.h>
  26 #include <linux/device.h>
  27
  28 #include <mtd/mtd-abi.h>
  29
  30 #include <asm/div64.h>
  31
  32 #define MTD_CHAR_MAJOR 90
  33 #define MTD_BLOCK_MAJOR 31
  34
  35 #define MTD_ERASE_PENDING       0x01
  36 #define MTD_ERASING             0x02
  37 #define MTD_ERASE_SUSPEND       0x04
  38 #define MTD_ERASE_DONE          0x08
  39 #define MTD_ERASE_FAILED        0x10
  40
  41 #define MTD_FAIL_ADDR_UNKNOWN -1LL
  42
  43 /*
  44  * If the erase fails, fail_addr might indicate exactly which block failed. If
  45  * fail_addr = MTD_FAIL_ADDR_UNKNOWN, the failure was not at the device level
  46  * or was not specific to any particular block.
  47  */
  48 struct erase_info {
  49         struct mtd_info *mtd;
  50         uint64_t addr;
  51         uint64_t len;
  52         uint64_t fail_addr;
  53         u_long time;
  54         u_long retries;
  55         unsigned dev;
  56         unsigned cell;
  57         void (*callback) (struct erase_info *self);
  58         u_long priv;
  59         u_char state;
  60         struct erase_info *next;
  61 };
  62
  63 struct mtd_erase_region_info {
  64         uint64_t offset;                /* At which this region starts, from the beginning of the MTD */
  65         uint32_t erasesize;             /* For this region */
  66         uint32_t numblocks;             /* Number of blocks of erasesize in this region */
  67         unsigned long *lockmap;         /* If keeping bitmap of locks */
  68 };
  69
  70 /**
  71  * struct mtd_oob_ops - oob operation operands
  72  * @mode:       operation mode
  73  *
  74  * @len:        number of data bytes to write/read
  75  *
  76  * @retlen:     number of data bytes written/read
  77  *
  78  * @ooblen:     number of oob bytes to write/read
  79  * @oobretlen:  number of oob bytes written/read
  80  * @ooboffs:    offset of oob data in the oob area (only relevant when
  81  *              mode = MTD_OPS_PLACE_OOB or MTD_OPS_RAW)
  82  * @datbuf:     data buffer - if NULL only oob data are read/written
  83  * @oobbuf:     oob data buffer
  84  *
  85  * Note, it is allowed to read more than one OOB area at one go, but not write.
  86  * The interface assumes that the OOB write requests program only one page's
  87  * OOB area.
  88  */
  89 struct mtd_oob_ops {
  90         unsigned int    mode;
  91         size_t          len;
  92         size_t          retlen;
  93         size_t          ooblen;
  94         size_t          oobretlen;
  95         uint32_t        ooboffs;
  96         uint8_t         *datbuf;
  97         uint8_t         *oobbuf;
  98 };
  99
 100 #define MTD_MAX_OOBFREE_ENTRIES_LARGE   32
 101 #define MTD_MAX_ECCPOS_ENTRIES_LARGE    448
 102 /*
 103  * Internal ECC layout control structure. For historical reasons, there is a
 104  * similar, smaller struct nand_ecclayout_user (in mtd-abi.h) that is retained
 105  * for export to user-space via the ECCGETLAYOUT ioctl.
 106  * nand_ecclayout should be expandable in the future simply by the above macros.
 107  */
 108 struct nand_ecclayout {
 109         __u32 eccbytes;
 110         __u32 eccpos[MTD_MAX_ECCPOS_ENTRIES_LARGE];
 111         __u32 oobavail;
 112         struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES_LARGE];
 113 };
 114
 115 struct module;  /* only needed for owner field in mtd_info */
 116
 117 struct mtd_info {
 118         u_char type;
 119         uint32_t flags;
 120         uint64_t size;   // Total size of the MTD
 121
 122         /* "Major" erase size for the device. Naïve users may take this
 123          * to be the only erase size available, or may use the more detailed
 124          * information below if they desire
 125          */
 126         uint32_t erasesize;
 127         /* Minimal writable flash unit size. In case of NOR flash it is 1 (even
 128          * though individual bits can be cleared), in case of NAND flash it is
 129          * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
 130          * it is of ECC block size, etc. It is illegal to have writesize = 0.
 131          * Any driver registering a struct mtd_info must ensure a writesize of
 132          * 1 or larger.
 133          */
 134         uint32_t writesize;
 135
 136         /*
 137          * Size of the write buffer used by the MTD. MTD devices having a write
 138          * buffer can write multiple writesize chunks at a time. E.g. while
 139          * writing 4 * writesize bytes to a device with 2 * writesize bytes
 140          * buffer the MTD driver can (but doesn't have to) do 2 writesize
 141          * operations, but not 4. Currently, all NANDs have writebufsize
 142          * equivalent to writesize (NAND page size). Some NOR flashes do have
 143          * writebufsize greater than writesize.
 144          */
 145         uint32_t writebufsize;
 146
 147         uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)
 148         uint32_t oobavail;  // Available OOB bytes per block
 149
 150         /*
 151          * If erasesize is a power of 2 then the shift is stored in
 152          * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
 153          */
 154         unsigned int erasesize_shift;
 155         unsigned int writesize_shift;
 156         /* Masks based on erasesize_shift and writesize_shift */
 157         unsigned int erasesize_mask;
 158         unsigned int writesize_mask;
 159
 160         // Kernel-only stuff starts here.
 161         const char *name;
 162         int index;
 163
 164         /* ECC layout structure pointer - read only! */
 165         struct nand_ecclayout *ecclayout;
 166
 167         /* Data for variable erase regions. If numeraseregions is zero,
 168          * it means that the whole device has erasesize as given above.
 169          */
 170         int numeraseregions;
 171         struct mtd_erase_region_info *eraseregions;
 172
 173         /*
 174          * Do not call via these pointers, use corresponding mtd_*()
 175          * wrappers instead.
 176          */
 177         int (*erase) (struct mtd_info *mtd, struct erase_info *instr);
 178         int (*point) (struct mtd_info *mtd, loff_t from, size_t len,
 179                       size_t *retlen, void **virt, resource_size_t *phys);
 180         void (*unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
 181         unsigned long (*get_unmapped_area) (struct mtd_info *mtd,
 182                                             unsigned long len,
 183                                             unsigned long offset,
 184                                             unsigned long flags);
 185         int (*read) (struct mtd_info *mtd, loff_t from, size_t len,
 186                      size_t *retlen, u_char *buf);
 187         int (*write) (struct mtd_info *mtd, loff_t to, size_t len,
 188                       size_t *retlen, const u_char *buf);
 189         int (*panic_write) (struct mtd_info *mtd, loff_t to, size_t len,
 190                             size_t *retlen, const u_char *buf);
 191         int (*read_oob) (struct mtd_info *mtd, loff_t from,
 192                          struct mtd_oob_ops *ops);
 193         int (*write_oob) (struct mtd_info *mtd, loff_t to,
 194                           struct mtd_oob_ops *ops);
 195         int (*get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf,
 196                                    size_t len);
 197         int (*read_fact_prot_reg) (struct mtd_info *mtd, loff_t from,
 198                                    size_t len, size_t *retlen, u_char *buf);
 199         int (*get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf,
 200                                    size_t len);
 201         int (*read_user_prot_reg) (struct mtd_info *mtd, loff_t from,
 202                                    size_t len, size_t *retlen, u_char *buf);
 203         int (*write_user_prot_reg) (struct mtd_info *mtd, loff_t to, size_t len,
 204                                     size_t *retlen, u_char *buf);
 205         int (*lock_user_prot_reg) (struct mtd_info *mtd, loff_t from,
 206                                    size_t len);
 207         int (*writev) (struct mtd_info *mtd, const struct kvec *vecs,
 208                         unsigned long count, loff_t to, size_t *retlen);
 209         void (*sync) (struct mtd_info *mtd);
 210         int (*lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 211         int (*unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 212         int (*is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 213         int (*block_isbad) (struct mtd_info *mtd, loff_t ofs);
 214         int (*suspend) (struct mtd_info *mtd);
 215         void (*resume) (struct mtd_info *mtd);
 216
 217         /* Backing device capabilities for this device
 218          * - provides mmap capabilities
 219          */
 220         struct backing_dev_info *backing_dev_info;
 221
 222         /* Bad block management functions */
 223         int (*block_markbad) (struct mtd_info *mtd, loff_t ofs);
 224
 225         struct notifier_block reboot_notifier;  /* default mode before reboot */
 226
 227         /* ECC status information */
 228         struct mtd_ecc_stats ecc_stats;
 229         /* Subpage shift (NAND) */
 230         int subpage_sft;
 231
 232         void *priv;
 233
 234         struct module *owner;
 235         struct device dev;
 236         int usecount;
 237
 238         /* If the driver is something smart, like UBI, it may need to maintain
 239          * its own reference counting. The below functions are only for driver.
 240          * The driver may register its callbacks. These callbacks are not
 241          * supposed to be called by MTD users */
 242         int (*get_device) (struct mtd_info *mtd);
 243         void (*put_device) (struct mtd_info *mtd);
 244 };
 245
 246 /*
 247  * Erase is an asynchronous operation.  Device drivers are supposed
 248  * to call instr->callback() whenever the operation completes, even
 249  * if it completes with a failure.
 250  * Callers are supposed to pass a callback function and wait for it
 251  * to be called before writing to the block.
 252  */
 253 static inline int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
 254 {
 255         return mtd->erase(mtd, instr);
 256 }
 257
 258 /*
 259  * This stuff for eXecute-In-Place. phys is optional and may be set to NULL.
 260  */
 261 static inline int mtd_point(struct mtd_info *mtd, loff_t from, size_t len,
 262                             size_t *retlen, void **virt, resource_size_t *phys)
 263 {
 264         return mtd->point(mtd, from, len, retlen, virt, phys);
 265 }
 266
 267 /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
 268 static inline void mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
 269 {
 270         return mtd->unpoint(mtd, from, len);
 271 }
 272
 273 /*
 274  * Allow NOMMU mmap() to directly map the device (if not NULL)
 275  * - return the address to which the offset maps
 276  * - return -ENOSYS to indicate refusal to do the mapping
 277  */
 278 static inline unsigned long mtd_get_unmapped_area(struct mtd_info *mtd,
 279                                                   unsigned long len,
 280                                                   unsigned long offset,
 281                                                   unsigned long flags)
 282 {
 283         return mtd->get_unmapped_area(mtd, len, offset, flags);
 284 }
 285
 286 static inline int mtd_read(struct mtd_info *mtd, loff_t from, size_t len,
 287                            size_t *retlen, u_char *buf)
 288 {
 289         return mtd->read(mtd, from, len, retlen, buf);
 290 }
 291
 292 static inline int mtd_write(struct mtd_info *mtd, loff_t to, size_t len,
 293                             size_t *retlen, const u_char *buf)
 294 {
 295         return mtd->write(mtd, to, len, retlen, buf);
 296 }
 297
 298 /*
 299  * In blackbox flight recorder like scenarios we want to make successful writes
 300  * in interrupt context. panic_write() is only intended to be called when its
 301  * known the kernel is about to panic and we need the write to succeed. Since
 302  * the kernel is not going to be running for much longer, this function can
 303  * break locks and delay to ensure the write succeeds (but not sleep).
 304  */
 305 static inline int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
 306                                   size_t *retlen, const u_char *buf)
 307 {
 308         return mtd->panic_write(mtd, to, len, retlen, buf);
 309 }
 310
 311 static inline int mtd_read_oob(struct mtd_info *mtd, loff_t from,
 312                                struct mtd_oob_ops *ops)
 313 {
 314         return mtd->read_oob(mtd, from, ops);
 315 }
 316
 317 static inline int mtd_write_oob(struct mtd_info *mtd, loff_t to,
 318                                 struct mtd_oob_ops *ops)
 319 {
 320         return mtd->write_oob(mtd, to, ops);
 321 }
 322
 323 /*
 324  * Method to access the protection register area, present in some flash
 325  * devices. The user data is one time programmable but the factory data is read
 326  * only.
 327  */
 328 static inline int mtd_get_fact_prot_info(struct mtd_info *mtd,
 329                                          struct otp_info *buf, size_t len)
 330 {
 331         return mtd->get_fact_prot_info(mtd, buf, len);
 332 }
 333
 334 static inline int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
 335                                          size_t len, size_t *retlen,
 336                                          u_char *buf)
 337 {
 338         return mtd->read_fact_prot_reg(mtd, from, len, retlen, buf);
 339 }
 340
 341 static inline int mtd_get_user_prot_info(struct mtd_info *mtd,
 342                                          struct otp_info *buf,
 343                                          size_t len)
 344 {
 345         return mtd->get_user_prot_info(mtd, buf, len);
 346 }
 347
 348 static inline int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
 349                                          size_t len, size_t *retlen,
 350                                          u_char *buf)
 351 {
 352         return mtd->read_user_prot_reg(mtd, from, len, retlen, buf);
 353 }
 354
 355 static inline int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to,
 356                                           size_t len, size_t *retlen,
 357                                           u_char *buf)
 358 {
 359         return mtd->write_user_prot_reg(mtd, to, len, retlen, buf);
 360 }
 361
 362 static inline int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
 363                                          size_t len)
 364 {
 365         return mtd->lock_user_prot_reg(mtd, from, len);
 366 }
 367
 368 /*
 369  * kvec-based read/write method. NB: The 'count' parameter is the number of
 370  * _vectors_, each of which contains an (ofs, len) tuple.
 371  */
 372 static inline int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
 373                              unsigned long count, loff_t to, size_t *retlen)
 374 {
 375         return mtd->writev(mtd, vecs, count, to, retlen);
 376 }
 377
 378 static inline void mtd_sync(struct mtd_info *mtd)
 379 {
 380         mtd->sync(mtd);
 381 }
 382
 383 /* Chip-supported device locking */
 384 static inline int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 385 {
 386         return mtd->lock(mtd, ofs, len);
 387 }
 388
 389 static inline int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 390 {
 391         return mtd->unlock(mtd, ofs, len);
 392 }
 393
 394 static inline int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 395 {
 396         return mtd->is_locked(mtd, ofs, len);
 397 }
 398
 399 static inline int mtd_suspend(struct mtd_info *mtd)
 400 {
 401         return mtd->suspend(mtd);
 402 }
 403
 404 static inline void mtd_resume(struct mtd_info *mtd)
 405 {
 406         mtd->resume(mtd);
 407 }
 408
 409 static inline int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs)
 410 {
 411         return mtd->block_isbad(mtd, ofs);
 412 }
 413
 414 static inline struct mtd_info *dev_to_mtd(struct device *dev)
 415 {
 416         return dev ? dev_get_drvdata(dev) : NULL;
 417 }
 418
 419 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
 420 {
 421         if (mtd->erasesize_shift)
 422                 return sz >> mtd->erasesize_shift;
 423         do_div(sz, mtd->erasesize);
 424         return sz;
 425 }
 426
 427 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
 428 {
 429         if (mtd->erasesize_shift)
 430                 return sz & mtd->erasesize_mask;
 431         return do_div(sz, mtd->erasesize);
 432 }
 433
 434 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
 435 {
 436         if (mtd->writesize_shift)
 437                 return sz >> mtd->writesize_shift;
 438         do_div(sz, mtd->writesize);
 439         return sz;
 440 }
 441
 442 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
 443 {
 444         if (mtd->writesize_shift)
 445                 return sz & mtd->writesize_mask;
 446         return do_div(sz, mtd->writesize);
 447 }
 448
 449         /* Kernel-side ioctl definitions */
 450
 451 struct mtd_partition;
 452 struct mtd_part_parser_data;
 453
 454 extern int mtd_device_parse_register(struct mtd_info *mtd,
 455                               const char **part_probe_types,
 456                               struct mtd_part_parser_data *parser_data,
 457                               const struct mtd_partition *defparts,
 458                               int defnr_parts);
 459 #define mtd_device_register(master, parts, nr_parts)    \
 460         mtd_device_parse_register(master, NULL, NULL, parts, nr_parts)
 461 extern int mtd_device_unregister(struct mtd_info *master);
 462 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
 463 extern int __get_mtd_device(struct mtd_info *mtd);
 464 extern void __put_mtd_device(struct mtd_info *mtd);
 465 extern struct mtd_info *get_mtd_device_nm(const char *name);
 466 extern void put_mtd_device(struct mtd_info *mtd);
 467
 468
 469 struct mtd_notifier {
 470         void (*add)(struct mtd_info *mtd);
 471         void (*remove)(struct mtd_info *mtd);
 472         struct list_head list;
 473 };
 474
 475
 476 extern void register_mtd_user (struct mtd_notifier *new);
 477 extern int unregister_mtd_user (struct mtd_notifier *old);
 478
 479 int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
 480                        unsigned long count, loff_t to, size_t *retlen);
 481
 482 int default_mtd_readv(struct mtd_info *mtd, struct kvec *vecs,
 483                       unsigned long count, loff_t from, size_t *retlen);
 484
 485 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size);
 486
 487 void mtd_erase_callback(struct erase_info *instr);
 488
 489 static inline int mtd_is_bitflip(int err) {
 490         return err == -EUCLEAN;
 491 }
 492
 493 static inline int mtd_is_eccerr(int err) {
 494         return err == -EBADMSG;
 495 }
 496
 497 static inline int mtd_is_bitflip_or_eccerr(int err) {
 498         return mtd_is_bitflip(err) || mtd_is_eccerr(err);
 499 }
 500
 501 #endif /* __MTD_MTD_H__ */