linux/include/linux/mtd/mtd.h
<<
>>
Prefs
   1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2/*
   3 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> et al.
   4 */
   5
   6#ifndef __MTD_MTD_H__
   7#define __MTD_MTD_H__
   8
   9#include <linux/types.h>
  10#include <linux/uio.h>
  11#include <linux/list.h>
  12#include <linux/notifier.h>
  13#include <linux/device.h>
  14#include <linux/of.h>
  15#include <linux/nvmem-provider.h>
  16
  17#include <mtd/mtd-abi.h>
  18
  19#include <asm/div64.h>
  20
  21#define MTD_FAIL_ADDR_UNKNOWN -1LL
  22
  23struct mtd_info;
  24
  25/*
  26 * If the erase fails, fail_addr might indicate exactly which block failed. If
  27 * fail_addr = MTD_FAIL_ADDR_UNKNOWN, the failure was not at the device level
  28 * or was not specific to any particular block.
  29 */
  30struct erase_info {
  31        uint64_t addr;
  32        uint64_t len;
  33        uint64_t fail_addr;
  34};
  35
  36struct mtd_erase_region_info {
  37        uint64_t offset;                /* At which this region starts, from the beginning of the MTD */
  38        uint32_t erasesize;             /* For this region */
  39        uint32_t numblocks;             /* Number of blocks of erasesize in this region */
  40        unsigned long *lockmap;         /* If keeping bitmap of locks */
  41};
  42
  43/**
  44 * struct mtd_oob_ops - oob operation operands
  45 * @mode:       operation mode
  46 *
  47 * @len:        number of data bytes to write/read
  48 *
  49 * @retlen:     number of data bytes written/read
  50 *
  51 * @ooblen:     number of oob bytes to write/read
  52 * @oobretlen:  number of oob bytes written/read
  53 * @ooboffs:    offset of oob data in the oob area (only relevant when
  54 *              mode = MTD_OPS_PLACE_OOB or MTD_OPS_RAW)
  55 * @datbuf:     data buffer - if NULL only oob data are read/written
  56 * @oobbuf:     oob data buffer
  57 *
  58 * Note, some MTD drivers do not allow you to write more than one OOB area at
  59 * one go. If you try to do that on such an MTD device, -EINVAL will be
  60 * returned. If you want to make your implementation portable on all kind of MTD
  61 * devices you should split the write request into several sub-requests when the
  62 * request crosses a page boundary.
  63 */
  64struct mtd_oob_ops {
  65        unsigned int    mode;
  66        size_t          len;
  67        size_t          retlen;
  68        size_t          ooblen;
  69        size_t          oobretlen;
  70        uint32_t        ooboffs;
  71        uint8_t         *datbuf;
  72        uint8_t         *oobbuf;
  73};
  74
  75#define MTD_MAX_OOBFREE_ENTRIES_LARGE   32
  76#define MTD_MAX_ECCPOS_ENTRIES_LARGE    640
  77/**
  78 * struct mtd_oob_region - oob region definition
  79 * @offset: region offset
  80 * @length: region length
  81 *
  82 * This structure describes a region of the OOB area, and is used
  83 * to retrieve ECC or free bytes sections.
  84 * Each section is defined by an offset within the OOB area and a
  85 * length.
  86 */
  87struct mtd_oob_region {
  88        u32 offset;
  89        u32 length;
  90};
  91
  92/*
  93 * struct mtd_ooblayout_ops - NAND OOB layout operations
  94 * @ecc: function returning an ECC region in the OOB area.
  95 *       Should return -ERANGE if %section exceeds the total number of
  96 *       ECC sections.
  97 * @free: function returning a free region in the OOB area.
  98 *        Should return -ERANGE if %section exceeds the total number of
  99 *        free sections.
 100 */
 101struct mtd_ooblayout_ops {
 102        int (*ecc)(struct mtd_info *mtd, int section,
 103                   struct mtd_oob_region *oobecc);
 104        int (*free)(struct mtd_info *mtd, int section,
 105                    struct mtd_oob_region *oobfree);
 106};
 107
 108/**
 109 * struct mtd_pairing_info - page pairing information
 110 *
 111 * @pair: pair id
 112 * @group: group id
 113 *
 114 * The term "pair" is used here, even though TLC NANDs might group pages by 3
 115 * (3 bits in a single cell). A pair should regroup all pages that are sharing
 116 * the same cell. Pairs are then indexed in ascending order.
 117 *
 118 * @group is defining the position of a page in a given pair. It can also be
 119 * seen as the bit position in the cell: page attached to bit 0 belongs to
 120 * group 0, page attached to bit 1 belongs to group 1, etc.
 121 *
 122 * Example:
 123 * The H27UCG8T2BTR-BC datasheet describes the following pairing scheme:
 124 *
 125 *              group-0         group-1
 126 *
 127 *  pair-0      page-0          page-4
 128 *  pair-1      page-1          page-5
 129 *  pair-2      page-2          page-8
 130 *  ...
 131 *  pair-127    page-251        page-255
 132 *
 133 *
 134 * Note that the "group" and "pair" terms were extracted from Samsung and
 135 * Hynix datasheets, and might be referenced under other names in other
 136 * datasheets (Micron is describing this concept as "shared pages").
 137 */
 138struct mtd_pairing_info {
 139        int pair;
 140        int group;
 141};
 142
 143/**
 144 * struct mtd_pairing_scheme - page pairing scheme description
 145 *
 146 * @ngroups: number of groups. Should be related to the number of bits
 147 *           per cell.
 148 * @get_info: converts a write-unit (page number within an erase block) into
 149 *            mtd_pairing information (pair + group). This function should
 150 *            fill the info parameter based on the wunit index or return
 151 *            -EINVAL if the wunit parameter is invalid.
 152 * @get_wunit: converts pairing information into a write-unit (page) number.
 153 *             This function should return the wunit index pointed by the
 154 *             pairing information described in the info argument. It should
 155 *             return -EINVAL, if there's no wunit corresponding to the
 156 *             passed pairing information.
 157 *
 158 * See mtd_pairing_info documentation for a detailed explanation of the
 159 * pair and group concepts.
 160 *
 161 * The mtd_pairing_scheme structure provides a generic solution to represent
 162 * NAND page pairing scheme. Instead of exposing two big tables to do the
 163 * write-unit <-> (pair + group) conversions, we ask the MTD drivers to
 164 * implement the ->get_info() and ->get_wunit() functions.
 165 *
 166 * MTD users will then be able to query these information by using the
 167 * mtd_pairing_info_to_wunit() and mtd_wunit_to_pairing_info() helpers.
 168 *
 169 * @ngroups is here to help MTD users iterating over all the pages in a
 170 * given pair. This value can be retrieved by MTD users using the
 171 * mtd_pairing_groups() helper.
 172 *
 173 * Examples are given in the mtd_pairing_info_to_wunit() and
 174 * mtd_wunit_to_pairing_info() documentation.
 175 */
 176struct mtd_pairing_scheme {
 177        int ngroups;
 178        int (*get_info)(struct mtd_info *mtd, int wunit,
 179                        struct mtd_pairing_info *info);
 180        int (*get_wunit)(struct mtd_info *mtd,
 181                         const struct mtd_pairing_info *info);
 182};
 183
 184struct module;  /* only needed for owner field in mtd_info */
 185
 186/**
 187 * struct mtd_debug_info - debugging information for an MTD device.
 188 *
 189 * @dfs_dir: direntry object of the MTD device debugfs directory
 190 */
 191struct mtd_debug_info {
 192        struct dentry *dfs_dir;
 193
 194        const char *partname;
 195        const char *partid;
 196};
 197
 198/**
 199 * struct mtd_part - MTD partition specific fields
 200 *
 201 * @node: list node used to add an MTD partition to the parent partition list
 202 * @offset: offset of the partition relatively to the parent offset
 203 * @size: partition size. Should be equal to mtd->size unless
 204 *        MTD_SLC_ON_MLC_EMULATION is set
 205 * @flags: original flags (before the mtdpart logic decided to tweak them based
 206 *         on flash constraints, like eraseblock/pagesize alignment)
 207 *
 208 * This struct is embedded in mtd_info and contains partition-specific
 209 * properties/fields.
 210 */
 211struct mtd_part {
 212        struct list_head node;
 213        u64 offset;
 214        u64 size;
 215        u32 flags;
 216};
 217
 218/**
 219 * struct mtd_master - MTD master specific fields
 220 *
 221 * @partitions_lock: lock protecting accesses to the partition list. Protects
 222 *                   not only the master partition list, but also all
 223 *                   sub-partitions.
 224 * @suspended: et to 1 when the device is suspended, 0 otherwise
 225 *
 226 * This struct is embedded in mtd_info and contains master-specific
 227 * properties/fields. The master is the root MTD device from the MTD partition
 228 * point of view.
 229 */
 230struct mtd_master {
 231        struct mutex partitions_lock;
 232        unsigned int suspended : 1;
 233};
 234
 235struct mtd_info {
 236        u_char type;
 237        uint32_t flags;
 238        uint64_t size;   // Total size of the MTD
 239
 240        /* "Major" erase size for the device. Naïve users may take this
 241         * to be the only erase size available, or may use the more detailed
 242         * information below if they desire
 243         */
 244        uint32_t erasesize;
 245        /* Minimal writable flash unit size. In case of NOR flash it is 1 (even
 246         * though individual bits can be cleared), in case of NAND flash it is
 247         * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
 248         * it is of ECC block size, etc. It is illegal to have writesize = 0.
 249         * Any driver registering a struct mtd_info must ensure a writesize of
 250         * 1 or larger.
 251         */
 252        uint32_t writesize;
 253
 254        /*
 255         * Size of the write buffer used by the MTD. MTD devices having a write
 256         * buffer can write multiple writesize chunks at a time. E.g. while
 257         * writing 4 * writesize bytes to a device with 2 * writesize bytes
 258         * buffer the MTD driver can (but doesn't have to) do 2 writesize
 259         * operations, but not 4. Currently, all NANDs have writebufsize
 260         * equivalent to writesize (NAND page size). Some NOR flashes do have
 261         * writebufsize greater than writesize.
 262         */
 263        uint32_t writebufsize;
 264
 265        uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)
 266        uint32_t oobavail;  // Available OOB bytes per block
 267
 268        /*
 269         * If erasesize is a power of 2 then the shift is stored in
 270         * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
 271         */
 272        unsigned int erasesize_shift;
 273        unsigned int writesize_shift;
 274        /* Masks based on erasesize_shift and writesize_shift */
 275        unsigned int erasesize_mask;
 276        unsigned int writesize_mask;
 277
 278        /*
 279         * read ops return -EUCLEAN if max number of bitflips corrected on any
 280         * one region comprising an ecc step equals or exceeds this value.
 281         * Settable by driver, else defaults to ecc_strength.  User can override
 282         * in sysfs.  N.B. The meaning of the -EUCLEAN return code has changed;
 283         * see Documentation/ABI/testing/sysfs-class-mtd for more detail.
 284         */
 285        unsigned int bitflip_threshold;
 286
 287        /* Kernel-only stuff starts here. */
 288        const char *name;
 289        int index;
 290
 291        /* OOB layout description */
 292        const struct mtd_ooblayout_ops *ooblayout;
 293
 294        /* NAND pairing scheme, only provided for MLC/TLC NANDs */
 295        const struct mtd_pairing_scheme *pairing;
 296
 297        /* the ecc step size. */
 298        unsigned int ecc_step_size;
 299
 300        /* max number of correctible bit errors per ecc step */
 301        unsigned int ecc_strength;
 302
 303        /* Data for variable erase regions. If numeraseregions is zero,
 304         * it means that the whole device has erasesize as given above.
 305         */
 306        int numeraseregions;
 307        struct mtd_erase_region_info *eraseregions;
 308
 309        /*
 310         * Do not call via these pointers, use corresponding mtd_*()
 311         * wrappers instead.
 312         */
 313        int (*_erase) (struct mtd_info *mtd, struct erase_info *instr);
 314        int (*_point) (struct mtd_info *mtd, loff_t from, size_t len,
 315                       size_t *retlen, void **virt, resource_size_t *phys);
 316        int (*_unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
 317        int (*_read) (struct mtd_info *mtd, loff_t from, size_t len,
 318                      size_t *retlen, u_char *buf);
 319        int (*_write) (struct mtd_info *mtd, loff_t to, size_t len,
 320                       size_t *retlen, const u_char *buf);
 321        int (*_panic_write) (struct mtd_info *mtd, loff_t to, size_t len,
 322                             size_t *retlen, const u_char *buf);
 323        int (*_read_oob) (struct mtd_info *mtd, loff_t from,
 324                          struct mtd_oob_ops *ops);
 325        int (*_write_oob) (struct mtd_info *mtd, loff_t to,
 326                           struct mtd_oob_ops *ops);
 327        int (*_get_fact_prot_info) (struct mtd_info *mtd, size_t len,
 328                                    size_t *retlen, struct otp_info *buf);
 329        int (*_read_fact_prot_reg) (struct mtd_info *mtd, loff_t from,
 330                                    size_t len, size_t *retlen, u_char *buf);
 331        int (*_get_user_prot_info) (struct mtd_info *mtd, size_t len,
 332                                    size_t *retlen, struct otp_info *buf);
 333        int (*_read_user_prot_reg) (struct mtd_info *mtd, loff_t from,
 334                                    size_t len, size_t *retlen, u_char *buf);
 335        int (*_write_user_prot_reg) (struct mtd_info *mtd, loff_t to,
 336                                     size_t len, size_t *retlen, u_char *buf);
 337        int (*_lock_user_prot_reg) (struct mtd_info *mtd, loff_t from,
 338                                    size_t len);
 339        int (*_writev) (struct mtd_info *mtd, const struct kvec *vecs,
 340                        unsigned long count, loff_t to, size_t *retlen);
 341        void (*_sync) (struct mtd_info *mtd);
 342        int (*_lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 343        int (*_unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 344        int (*_is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
 345        int (*_block_isreserved) (struct mtd_info *mtd, loff_t ofs);
 346        int (*_block_isbad) (struct mtd_info *mtd, loff_t ofs);
 347        int (*_block_markbad) (struct mtd_info *mtd, loff_t ofs);
 348        int (*_max_bad_blocks) (struct mtd_info *mtd, loff_t ofs, size_t len);
 349        int (*_suspend) (struct mtd_info *mtd);
 350        void (*_resume) (struct mtd_info *mtd);
 351        void (*_reboot) (struct mtd_info *mtd);
 352        /*
 353         * If the driver is something smart, like UBI, it may need to maintain
 354         * its own reference counting. The below functions are only for driver.
 355         */
 356        int (*_get_device) (struct mtd_info *mtd);
 357        void (*_put_device) (struct mtd_info *mtd);
 358
 359        /*
 360         * flag indicates a panic write, low level drivers can take appropriate
 361         * action if required to ensure writes go through
 362         */
 363        bool oops_panic_write;
 364
 365        struct notifier_block reboot_notifier;  /* default mode before reboot */
 366
 367        /* ECC status information */
 368        struct mtd_ecc_stats ecc_stats;
 369        /* Subpage shift (NAND) */
 370        int subpage_sft;
 371
 372        void *priv;
 373
 374        struct module *owner;
 375        struct device dev;
 376        int usecount;
 377        struct mtd_debug_info dbg;
 378        struct nvmem_device *nvmem;
 379
 380        /*
 381         * Parent device from the MTD partition point of view.
 382         *
 383         * MTD masters do not have any parent, MTD partitions do. The parent
 384         * MTD device can itself be a partition.
 385         */
 386        struct mtd_info *parent;
 387
 388        /* List of partitions attached to this MTD device */
 389        struct list_head partitions;
 390
 391        union {
 392                struct mtd_part part;
 393                struct mtd_master master;
 394        };
 395};
 396
 397static inline struct mtd_info *mtd_get_master(struct mtd_info *mtd)
 398{
 399        while (mtd->parent)
 400                mtd = mtd->parent;
 401
 402        return mtd;
 403}
 404
 405static inline u64 mtd_get_master_ofs(struct mtd_info *mtd, u64 ofs)
 406{
 407        while (mtd->parent) {
 408                ofs += mtd->part.offset;
 409                mtd = mtd->parent;
 410        }
 411
 412        return ofs;
 413}
 414
 415static inline bool mtd_is_partition(const struct mtd_info *mtd)
 416{
 417        return mtd->parent;
 418}
 419
 420static inline bool mtd_has_partitions(const struct mtd_info *mtd)
 421{
 422        return !list_empty(&mtd->partitions);
 423}
 424
 425int mtd_ooblayout_ecc(struct mtd_info *mtd, int section,
 426                      struct mtd_oob_region *oobecc);
 427int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte,
 428                                 int *section,
 429                                 struct mtd_oob_region *oobregion);
 430int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf,
 431                               const u8 *oobbuf, int start, int nbytes);
 432int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf,
 433                               u8 *oobbuf, int start, int nbytes);
 434int mtd_ooblayout_free(struct mtd_info *mtd, int section,
 435                       struct mtd_oob_region *oobfree);
 436int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf,
 437                                const u8 *oobbuf, int start, int nbytes);
 438int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf,
 439                                u8 *oobbuf, int start, int nbytes);
 440int mtd_ooblayout_count_freebytes(struct mtd_info *mtd);
 441int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd);
 442
 443static inline void mtd_set_ooblayout(struct mtd_info *mtd,
 444                                     const struct mtd_ooblayout_ops *ooblayout)
 445{
 446        mtd->ooblayout = ooblayout;
 447}
 448
 449static inline void mtd_set_pairing_scheme(struct mtd_info *mtd,
 450                                const struct mtd_pairing_scheme *pairing)
 451{
 452        mtd->pairing = pairing;
 453}
 454
 455static inline void mtd_set_of_node(struct mtd_info *mtd,
 456                                   struct device_node *np)
 457{
 458        mtd->dev.of_node = np;
 459        if (!mtd->name)
 460                of_property_read_string(np, "label", &mtd->name);
 461}
 462
 463static inline struct device_node *mtd_get_of_node(struct mtd_info *mtd)
 464{
 465        return dev_of_node(&mtd->dev);
 466}
 467
 468static inline u32 mtd_oobavail(struct mtd_info *mtd, struct mtd_oob_ops *ops)
 469{
 470        return ops->mode == MTD_OPS_AUTO_OOB ? mtd->oobavail : mtd->oobsize;
 471}
 472
 473static inline int mtd_max_bad_blocks(struct mtd_info *mtd,
 474                                     loff_t ofs, size_t len)
 475{
 476        struct mtd_info *master = mtd_get_master(mtd);
 477
 478        if (!master->_max_bad_blocks)
 479                return -ENOTSUPP;
 480
 481        if (mtd->size < (len + ofs) || ofs < 0)
 482                return -EINVAL;
 483
 484        return master->_max_bad_blocks(master, mtd_get_master_ofs(mtd, ofs),
 485                                       len);
 486}
 487
 488int mtd_wunit_to_pairing_info(struct mtd_info *mtd, int wunit,
 489                              struct mtd_pairing_info *info);
 490int mtd_pairing_info_to_wunit(struct mtd_info *mtd,
 491                              const struct mtd_pairing_info *info);
 492int mtd_pairing_groups(struct mtd_info *mtd);
 493int mtd_erase(struct mtd_info *mtd, struct erase_info *instr);
 494int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
 495              void **virt, resource_size_t *phys);
 496int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len);
 497unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
 498                                    unsigned long offset, unsigned long flags);
 499int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
 500             u_char *buf);
 501int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
 502              const u_char *buf);
 503int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
 504                    const u_char *buf);
 505
 506int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops);
 507int mtd_write_oob(struct mtd_info *mtd, loff_t to, struct mtd_oob_ops *ops);
 508
 509int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
 510                           struct otp_info *buf);
 511int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
 512                           size_t *retlen, u_char *buf);
 513int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
 514                           struct otp_info *buf);
 515int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
 516                           size_t *retlen, u_char *buf);
 517int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
 518                            size_t *retlen, u_char *buf);
 519int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len);
 520
 521int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
 522               unsigned long count, loff_t to, size_t *retlen);
 523
 524static inline void mtd_sync(struct mtd_info *mtd)
 525{
 526        struct mtd_info *master = mtd_get_master(mtd);
 527
 528        if (master->_sync)
 529                master->_sync(master);
 530}
 531
 532int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
 533int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
 534int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len);
 535int mtd_block_isreserved(struct mtd_info *mtd, loff_t ofs);
 536int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs);
 537int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs);
 538
 539static inline int mtd_suspend(struct mtd_info *mtd)
 540{
 541        struct mtd_info *master = mtd_get_master(mtd);
 542        int ret;
 543
 544        if (master->master.suspended)
 545                return 0;
 546
 547        ret = master->_suspend ? master->_suspend(master) : 0;
 548        if (ret)
 549                return ret;
 550
 551        master->master.suspended = 1;
 552        return 0;
 553}
 554
 555static inline void mtd_resume(struct mtd_info *mtd)
 556{
 557        struct mtd_info *master = mtd_get_master(mtd);
 558
 559        if (!master->master.suspended)
 560                return;
 561
 562        if (master->_resume)
 563                master->_resume(master);
 564
 565        master->master.suspended = 0;
 566}
 567
 568static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
 569{
 570        if (mtd->erasesize_shift)
 571                return sz >> mtd->erasesize_shift;
 572        do_div(sz, mtd->erasesize);
 573        return sz;
 574}
 575
 576static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
 577{
 578        if (mtd->erasesize_shift)
 579                return sz & mtd->erasesize_mask;
 580        return do_div(sz, mtd->erasesize);
 581}
 582
 583/**
 584 * mtd_align_erase_req - Adjust an erase request to align things on eraseblock
 585 *                       boundaries.
 586 * @mtd: the MTD device this erase request applies on
 587 * @req: the erase request to adjust
 588 *
 589 * This function will adjust @req->addr and @req->len to align them on
 590 * @mtd->erasesize. Of course we expect @mtd->erasesize to be != 0.
 591 */
 592static inline void mtd_align_erase_req(struct mtd_info *mtd,
 593                                       struct erase_info *req)
 594{
 595        u32 mod;
 596
 597        if (WARN_ON(!mtd->erasesize))
 598                return;
 599
 600        mod = mtd_mod_by_eb(req->addr, mtd);
 601        if (mod) {
 602                req->addr -= mod;
 603                req->len += mod;
 604        }
 605
 606        mod = mtd_mod_by_eb(req->addr + req->len, mtd);
 607        if (mod)
 608                req->len += mtd->erasesize - mod;
 609}
 610
 611static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
 612{
 613        if (mtd->writesize_shift)
 614                return sz >> mtd->writesize_shift;
 615        do_div(sz, mtd->writesize);
 616        return sz;
 617}
 618
 619static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
 620{
 621        if (mtd->writesize_shift)
 622                return sz & mtd->writesize_mask;
 623        return do_div(sz, mtd->writesize);
 624}
 625
 626static inline int mtd_wunit_per_eb(struct mtd_info *mtd)
 627{
 628        struct mtd_info *master = mtd_get_master(mtd);
 629
 630        return master->erasesize / mtd->writesize;
 631}
 632
 633static inline int mtd_offset_to_wunit(struct mtd_info *mtd, loff_t offs)
 634{
 635        return mtd_div_by_ws(mtd_mod_by_eb(offs, mtd), mtd);
 636}
 637
 638static inline loff_t mtd_wunit_to_offset(struct mtd_info *mtd, loff_t base,
 639                                         int wunit)
 640{
 641        return base + (wunit * mtd->writesize);
 642}
 643
 644
 645static inline int mtd_has_oob(const struct mtd_info *mtd)
 646{
 647        struct mtd_info *master = mtd_get_master((struct mtd_info *)mtd);
 648
 649        return master->_read_oob && master->_write_oob;
 650}
 651
 652static inline int mtd_type_is_nand(const struct mtd_info *mtd)
 653{
 654        return mtd->type == MTD_NANDFLASH || mtd->type == MTD_MLCNANDFLASH;
 655}
 656
 657static inline int mtd_can_have_bb(const struct mtd_info *mtd)
 658{
 659        struct mtd_info *master = mtd_get_master((struct mtd_info *)mtd);
 660
 661        return !!master->_block_isbad;
 662}
 663
 664        /* Kernel-side ioctl definitions */
 665
 666struct mtd_partition;
 667struct mtd_part_parser_data;
 668
 669extern int mtd_device_parse_register(struct mtd_info *mtd,
 670                                     const char * const *part_probe_types,
 671                                     struct mtd_part_parser_data *parser_data,
 672                                     const struct mtd_partition *defparts,
 673                                     int defnr_parts);
 674#define mtd_device_register(master, parts, nr_parts)    \
 675        mtd_device_parse_register(master, NULL, NULL, parts, nr_parts)
 676extern int mtd_device_unregister(struct mtd_info *master);
 677extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
 678extern int __get_mtd_device(struct mtd_info *mtd);
 679extern void __put_mtd_device(struct mtd_info *mtd);
 680extern struct mtd_info *get_mtd_device_nm(const char *name);
 681extern void put_mtd_device(struct mtd_info *mtd);
 682
 683
 684struct mtd_notifier {
 685        void (*add)(struct mtd_info *mtd);
 686        void (*remove)(struct mtd_info *mtd);
 687        struct list_head list;
 688};
 689
 690
 691extern void register_mtd_user (struct mtd_notifier *new);
 692extern int unregister_mtd_user (struct mtd_notifier *old);
 693void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size);
 694
 695static inline int mtd_is_bitflip(int err) {
 696        return err == -EUCLEAN;
 697}
 698
 699static inline int mtd_is_eccerr(int err) {
 700        return err == -EBADMSG;
 701}
 702
 703static inline int mtd_is_bitflip_or_eccerr(int err) {
 704        return mtd_is_bitflip(err) || mtd_is_eccerr(err);
 705}
 706
 707unsigned mtd_mmap_capabilities(struct mtd_info *mtd);
 708
 709#endif /* __MTD_MTD_H__ */
 710