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    640
 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         /*
 161          * read ops return -EUCLEAN if max number of bitflips corrected on any
 162          * one region comprising an ecc step equals or exceeds this value.
 163          * Settable by driver, else defaults to ecc_strength.  User can override
 164          * in sysfs.  N.B. The meaning of the -EUCLEAN return code has changed;
 165          * see Documentation/ABI/testing/sysfs-class-mtd for more detail.
 166          */
 167         unsigned int bitflip_threshold;
 168
 169         // Kernel-only stuff starts here.
 170         const char *name;
 171         int index;
 172
 173         /* ECC layout structure pointer - read only! */
 174         struct nand_ecclayout *ecclayout;
 175
 176         /* max number of correctible bit errors per ecc step */
 177         unsigned int ecc_strength;
 178
 179         /* Data for variable erase regions. If numeraseregions is zero,
 180          * it means that the whole device has erasesize as given above.
 181          */
 182         int numeraseregions;
 183         struct mtd_erase_region_info *eraseregions;
 184
 185         /*
 186          * Do not call via these pointers, use corresponding mtd_*()
 187          * wrappers instead.
 188          */
 189         int (*_erase) (struct mtd_info *mtd, struct erase_info *instr);
 190         int (*_point) (struct mtd_info *mtd, loff_t from, size_t len,
 191                        size_t *retlen, void **virt, resource_size_t *phys);
 192         int (*_unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
 193         unsigned long (*_get_unmapped_area) (struct mtd_info *mtd,
 194                                              unsigned long len,
 195                                              unsigned long offset,
 196                                              unsigned long flags);
 197         int (*_read) (struct mtd_info *mtd, loff_t from, size_t len,
 198                       size_t *retlen, u_char *buf);
 199         int (*_write) (struct mtd_info *mtd, loff_t to, size_t len,
 200                        size_t *retlen, const u_char *buf);
 201         int (*_panic_write) (struct mtd_info *mtd, loff_t to, size_t len,
 202                              size_t *retlen, const u_char *buf);
 203         int (*_read_oob) (struct mtd_info *mtd, loff_t from,
 204                           struct mtd_oob_ops *ops);
 205         int (*_write_oob) (struct mtd_info *mtd, loff_t to,
 206                            struct mtd_oob_ops *ops);
 207         int (*_get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf,
 208                                     size_t len);
 209         int (*_read_fact_prot_reg) (struct mtd_info *mtd, loff_t from,
 210                                     size_t len, size_t *retlen, u_char *buf);
 211         int (*_get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf,
 212                                     size_t len);
 213         int (*_read_user_prot_reg) (struct mtd_info *mtd, loff_t from,
 214                                     size_t len, size_t *retlen, u_char *buf);
 215         int (*_write_user_prot_reg) (struct mtd_info *mtd, loff_t to,
 216                                      size_t len, size_t *retlen, u_char *buf);
 217         int (*_lock_user_prot_reg) (struct mtd_info *mtd, loff_t from,
 218                                     size_t len);
 219         int (*_writev) (struct mtd_info *mtd, const struct kvec *vecs,
 220                         unsigned long count, loff_t to, size_t *retlen);
 221         void (*_sync) (struct mtd_info *mtd);
 222         int (*_lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 223         int (*_unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 224         int (*_is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 225         int (*_block_isbad) (struct mtd_info *mtd, loff_t ofs);
 226         int (*_block_markbad) (struct mtd_info *mtd, loff_t ofs);
 227         int (*_suspend) (struct mtd_info *mtd);
 228         void (*_resume) (struct mtd_info *mtd);
 229         /*
 230          * If the driver is something smart, like UBI, it may need to maintain
 231          * its own reference counting. The below functions are only for driver.
 232          */
 233         int (*_get_device) (struct mtd_info *mtd);
 234         void (*_put_device) (struct mtd_info *mtd);
 235
 236         /* Backing device capabilities for this device
 237          * - provides mmap capabilities
 238          */
 239         struct backing_dev_info *backing_dev_info;
 240
 241         struct notifier_block reboot_notifier;  /* default mode before reboot */
 242
 243         /* ECC status information */
 244         struct mtd_ecc_stats ecc_stats;
 245         /* Subpage shift (NAND) */
 246         int subpage_sft;
 247
 248         void *priv;
 249
 250         struct module *owner;
 251         struct device dev;
 252         int usecount;
 253 };
 254
 255 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr);
 256 int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
 257               void **virt, resource_size_t *phys);
 258 int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len);
 259 unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
 260                                     unsigned long offset, unsigned long flags);
 261 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
 262              u_char *buf);
 263 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
 264               const u_char *buf);
 265 int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
 266                     const u_char *buf);
 267
 268 int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops);
 269
 270 static inline int mtd_write_oob(struct mtd_info *mtd, loff_t to,
 271                                 struct mtd_oob_ops *ops)
 272 {
 273         ops->retlen = ops->oobretlen = 0;
 274         if (!mtd->_write_oob)
 275                 return -EOPNOTSUPP;
 276         if (!(mtd->flags & MTD_WRITEABLE))
 277                 return -EROFS;
 278         return mtd->_write_oob(mtd, to, ops);
 279 }
 280
 281 int mtd_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
 282                            size_t len);
 283 int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
 284                            size_t *retlen, u_char *buf);
 285 int mtd_get_user_prot_info(struct mtd_info *mtd, struct otp_info *buf,
 286                            size_t len);
 287 int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
 288                            size_t *retlen, u_char *buf);
 289 int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
 290                             size_t *retlen, u_char *buf);
 291 int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len);
 292
 293 int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
 294                unsigned long count, loff_t to, size_t *retlen);
 295
 296 static inline void mtd_sync(struct mtd_info *mtd)
 297 {
 298         if (mtd->_sync)
 299                 mtd->_sync(mtd);
 300 }
 301
 302 int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
 303 int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
 304 int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len);
 305 int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs);
 306 int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs);
 307
 308 static inline int mtd_suspend(struct mtd_info *mtd)
 309 {
 310         return mtd->_suspend ? mtd->_suspend(mtd) : 0;
 311 }
 312
 313 static inline void mtd_resume(struct mtd_info *mtd)
 314 {
 315         if (mtd->_resume)
 316                 mtd->_resume(mtd);
 317 }
 318
 319 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
 320 {
 321         if (mtd->erasesize_shift)
 322                 return sz >> mtd->erasesize_shift;
 323         do_div(sz, mtd->erasesize);
 324         return sz;
 325 }
 326
 327 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
 328 {
 329         if (mtd->erasesize_shift)
 330                 return sz & mtd->erasesize_mask;
 331         return do_div(sz, mtd->erasesize);
 332 }
 333
 334 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
 335 {
 336         if (mtd->writesize_shift)
 337                 return sz >> mtd->writesize_shift;
 338         do_div(sz, mtd->writesize);
 339         return sz;
 340 }
 341
 342 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
 343 {
 344         if (mtd->writesize_shift)
 345                 return sz & mtd->writesize_mask;
 346         return do_div(sz, mtd->writesize);
 347 }
 348
 349 static inline int mtd_has_oob(const struct mtd_info *mtd)
 350 {
 351         return mtd->_read_oob && mtd->_write_oob;
 352 }
 353
 354 static inline int mtd_can_have_bb(const struct mtd_info *mtd)
 355 {
 356         return !!mtd->_block_isbad;
 357 }
 358
 359         /* Kernel-side ioctl definitions */
 360
 361 struct mtd_partition;
 362 struct mtd_part_parser_data;
 363
 364 extern int mtd_device_parse_register(struct mtd_info *mtd,
 365                                      const char * const *part_probe_types,
 366                                      struct mtd_part_parser_data *parser_data,
 367                                      const struct mtd_partition *defparts,
 368                                      int defnr_parts);
 369 #define mtd_device_register(master, parts, nr_parts)    \
 370         mtd_device_parse_register(master, NULL, NULL, parts, nr_parts)
 371 extern int mtd_device_unregister(struct mtd_info *master);
 372 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
 373 extern int __get_mtd_device(struct mtd_info *mtd);
 374 extern void __put_mtd_device(struct mtd_info *mtd);
 375 extern struct mtd_info *get_mtd_device_nm(const char *name);
 376 extern void put_mtd_device(struct mtd_info *mtd);
 377
 378
 379 struct mtd_notifier {
 380         void (*add)(struct mtd_info *mtd);
 381         void (*remove)(struct mtd_info *mtd);
 382         struct list_head list;
 383 };
 384
 385
 386 extern void register_mtd_user (struct mtd_notifier *new);
 387 extern int unregister_mtd_user (struct mtd_notifier *old);
 388 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size);
 389
 390 void mtd_erase_callback(struct erase_info *instr);
 391
 392 static inline int mtd_is_bitflip(int err) {
 393         return err == -EUCLEAN;
 394 }
 395
 396 static inline int mtd_is_eccerr(int err) {
 397         return err == -EBADMSG;
 398 }
 399
 400 static inline int mtd_is_bitflip_or_eccerr(int err) {
 401         return mtd_is_bitflip(err) || mtd_is_eccerr(err);
 402 }
 403
 404 #endif /* __MTD_MTD_H__ */