linux/mtd/mtd.h

0001 /* SPDX-License-Identifier: GPL-2.0-or-later */
0002 /*
0003  * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> et al.
0004  */
0005
0006 #ifndef __MTD_MTD_H__
0007 #define __MTD_MTD_H__
0008
0009 #include <linux/types.h>
0010 #include <linux/uio.h>
0011 #include <linux/list.h>
0012 #include <linux/notifier.h>
0013 #include <linux/device.h>
0014 #include <linux/of.h>
0015 #include <linux/nvmem-provider.h>
0016
0017 #include <mtd/mtd-abi.h>
0018
0019 #include <asm/div64.h>
0020
0021 #define MTD_FAIL_ADDR_UNKNOWN -1LL
0022
0023 struct mtd_info;
0024
0025 /*
0026  * If the erase fails, fail_addr might indicate exactly which block failed. If
0027  * fail_addr = MTD_FAIL_ADDR_UNKNOWN, the failure was not at the device level
0028  * or was not specific to any particular block.
0029  */
0030 struct erase_info {
0031     uint64_t addr;
0032     uint64_t len;
0033     uint64_t fail_addr;
0034 };
0035
0036 struct mtd_erase_region_info {
0037     uint64_t offset;        /* At which this region starts, from the beginning of the MTD */
0038     uint32_t erasesize;     /* For this region */
0039     uint32_t numblocks;     /* Number of blocks of erasesize in this region */
0040     unsigned long *lockmap;     /* If keeping bitmap of locks */
0041 };
0042
0043 /**
0044  * struct mtd_oob_ops - oob operation operands
0045  * @mode:   operation mode
0046  *
0047  * @len:    number of data bytes to write/read
0048  *
0049  * @retlen: number of data bytes written/read
0050  *
0051  * @ooblen: number of oob bytes to write/read
0052  * @oobretlen:  number of oob bytes written/read
0053  * @ooboffs:    offset of oob data in the oob area (only relevant when
0054  *      mode = MTD_OPS_PLACE_OOB or MTD_OPS_RAW)
0055  * @datbuf: data buffer - if NULL only oob data are read/written
0056  * @oobbuf: oob data buffer
0057  *
0058  * Note, some MTD drivers do not allow you to write more than one OOB area at
0059  * one go. If you try to do that on such an MTD device, -EINVAL will be
0060  * returned. If you want to make your implementation portable on all kind of MTD
0061  * devices you should split the write request into several sub-requests when the
0062  * request crosses a page boundary.
0063  */
0064 struct mtd_oob_ops {
0065     unsigned int    mode;
0066     size_t      len;
0067     size_t      retlen;
0068     size_t      ooblen;
0069     size_t      oobretlen;
0070     uint32_t    ooboffs;
0071     uint8_t     *datbuf;
0072     uint8_t     *oobbuf;
0073 };
0074
0075 /**
0076  * struct mtd_oob_region - oob region definition
0077  * @offset: region offset
0078  * @length: region length
0079  *
0080  * This structure describes a region of the OOB area, and is used
0081  * to retrieve ECC or free bytes sections.
0082  * Each section is defined by an offset within the OOB area and a
0083  * length.
0084  */
0085 struct mtd_oob_region {
0086     u32 offset;
0087     u32 length;
0088 };
0089
0090 /*
0091  * struct mtd_ooblayout_ops - NAND OOB layout operations
0092  * @ecc: function returning an ECC region in the OOB area.
0093  *   Should return -ERANGE if %section exceeds the total number of
0094  *   ECC sections.
0095  * @free: function returning a free region in the OOB area.
0096  *    Should return -ERANGE if %section exceeds the total number of
0097  *    free sections.
0098  */
0099 struct mtd_ooblayout_ops {
0100     int (*ecc)(struct mtd_info *mtd, int section,
0101            struct mtd_oob_region *oobecc);
0102     int (*free)(struct mtd_info *mtd, int section,
0103             struct mtd_oob_region *oobfree);
0104 };
0105
0106 /**
0107  * struct mtd_pairing_info - page pairing information
0108  *
0109  * @pair: pair id
0110  * @group: group id
0111  *
0112  * The term "pair" is used here, even though TLC NANDs might group pages by 3
0113  * (3 bits in a single cell). A pair should regroup all pages that are sharing
0114  * the same cell. Pairs are then indexed in ascending order.
0115  *
0116  * @group is defining the position of a page in a given pair. It can also be
0117  * seen as the bit position in the cell: page attached to bit 0 belongs to
0118  * group 0, page attached to bit 1 belongs to group 1, etc.
0119  *
0120  * Example:
0121  * The H27UCG8T2BTR-BC datasheet describes the following pairing scheme:
0122  *
0123  *      group-0     group-1
0124  *
0125  *  pair-0  page-0      page-4
0126  *  pair-1  page-1      page-5
0127  *  pair-2  page-2      page-8
0128  *  ...
0129  *  pair-127    page-251    page-255
0130  *
0131  *
0132  * Note that the "group" and "pair" terms were extracted from Samsung and
0133  * Hynix datasheets, and might be referenced under other names in other
0134  * datasheets (Micron is describing this concept as "shared pages").
0135  */
0136 struct mtd_pairing_info {
0137     int pair;
0138     int group;
0139 };
0140
0141 /**
0142  * struct mtd_pairing_scheme - page pairing scheme description
0143  *
0144  * @ngroups: number of groups. Should be related to the number of bits
0145  *       per cell.
0146  * @get_info: converts a write-unit (page number within an erase block) into
0147  *        mtd_pairing information (pair + group). This function should
0148  *        fill the info parameter based on the wunit index or return
0149  *        -EINVAL if the wunit parameter is invalid.
0150  * @get_wunit: converts pairing information into a write-unit (page) number.
0151  *         This function should return the wunit index pointed by the
0152  *         pairing information described in the info argument. It should
0153  *         return -EINVAL, if there's no wunit corresponding to the
0154  *         passed pairing information.
0155  *
0156  * See mtd_pairing_info documentation for a detailed explanation of the
0157  * pair and group concepts.
0158  *
0159  * The mtd_pairing_scheme structure provides a generic solution to represent
0160  * NAND page pairing scheme. Instead of exposing two big tables to do the
0161  * write-unit <-> (pair + group) conversions, we ask the MTD drivers to
0162  * implement the ->get_info() and ->get_wunit() functions.
0163  *
0164  * MTD users will then be able to query these information by using the
0165  * mtd_pairing_info_to_wunit() and mtd_wunit_to_pairing_info() helpers.
0166  *
0167  * @ngroups is here to help MTD users iterating over all the pages in a
0168  * given pair. This value can be retrieved by MTD users using the
0169  * mtd_pairing_groups() helper.
0170  *
0171  * Examples are given in the mtd_pairing_info_to_wunit() and
0172  * mtd_wunit_to_pairing_info() documentation.
0173  */
0174 struct mtd_pairing_scheme {
0175     int ngroups;
0176     int (*get_info)(struct mtd_info *mtd, int wunit,
0177             struct mtd_pairing_info *info);
0178     int (*get_wunit)(struct mtd_info *mtd,
0179              const struct mtd_pairing_info *info);
0180 };
0181
0182 struct module;  /* only needed for owner field in mtd_info */
0183
0184 /**
0185  * struct mtd_debug_info - debugging information for an MTD device.
0186  *
0187  * @dfs_dir: direntry object of the MTD device debugfs directory
0188  */
0189 struct mtd_debug_info {
0190     struct dentry *dfs_dir;
0191 };
0192
0193 /**
0194  * struct mtd_part - MTD partition specific fields
0195  *
0196  * @node: list node used to add an MTD partition to the parent partition list
0197  * @offset: offset of the partition relatively to the parent offset
0198  * @size: partition size. Should be equal to mtd->size unless
0199  *    MTD_SLC_ON_MLC_EMULATION is set
0200  * @flags: original flags (before the mtdpart logic decided to tweak them based
0201  *     on flash constraints, like eraseblock/pagesize alignment)
0202  *
0203  * This struct is embedded in mtd_info and contains partition-specific
0204  * properties/fields.
0205  */
0206 struct mtd_part {
0207     struct list_head node;
0208     u64 offset;
0209     u64 size;
0210     u32 flags;
0211 };
0212
0213 /**
0214  * struct mtd_master - MTD master specific fields
0215  *
0216  * @partitions_lock: lock protecting accesses to the partition list. Protects
0217  *           not only the master partition list, but also all
0218  *           sub-partitions.
0219  * @suspended: et to 1 when the device is suspended, 0 otherwise
0220  *
0221  * This struct is embedded in mtd_info and contains master-specific
0222  * properties/fields. The master is the root MTD device from the MTD partition
0223  * point of view.
0224  */
0225 struct mtd_master {
0226     struct mutex partitions_lock;
0227     struct mutex chrdev_lock;
0228     unsigned int suspended : 1;
0229 };
0230
0231 struct mtd_info {
0232     u_char type;
0233     uint32_t flags;
0234     uint64_t size;   // Total size of the MTD
0235
0236     /* "Major" erase size for the device. Naïve users may take this
0237      * to be the only erase size available, or may use the more detailed
0238      * information below if they desire
0239      */
0240     uint32_t erasesize;
0241     /* Minimal writable flash unit size. In case of NOR flash it is 1 (even
0242      * though individual bits can be cleared), in case of NAND flash it is
0243      * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
0244      * it is of ECC block size, etc. It is illegal to have writesize = 0.
0245      * Any driver registering a struct mtd_info must ensure a writesize of
0246      * 1 or larger.
0247      */
0248     uint32_t writesize;
0249
0250     /*
0251      * Size of the write buffer used by the MTD. MTD devices having a write
0252      * buffer can write multiple writesize chunks at a time. E.g. while
0253      * writing 4 * writesize bytes to a device with 2 * writesize bytes
0254      * buffer the MTD driver can (but doesn't have to) do 2 writesize
0255      * operations, but not 4. Currently, all NANDs have writebufsize
0256      * equivalent to writesize (NAND page size). Some NOR flashes do have
0257      * writebufsize greater than writesize.
0258      */
0259     uint32_t writebufsize;
0260
0261     uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)
0262     uint32_t oobavail;  // Available OOB bytes per block
0263
0264     /*
0265      * If erasesize is a power of 2 then the shift is stored in
0266      * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
0267      */
0268     unsigned int erasesize_shift;
0269     unsigned int writesize_shift;
0270     /* Masks based on erasesize_shift and writesize_shift */
0271     unsigned int erasesize_mask;
0272     unsigned int writesize_mask;
0273
0274     /*
0275      * read ops return -EUCLEAN if max number of bitflips corrected on any
0276      * one region comprising an ecc step equals or exceeds this value.
0277      * Settable by driver, else defaults to ecc_strength.  User can override
0278      * in sysfs.  N.B. The meaning of the -EUCLEAN return code has changed;
0279      * see Documentation/ABI/testing/sysfs-class-mtd for more detail.
0280      */
0281     unsigned int bitflip_threshold;
0282
0283     /* Kernel-only stuff starts here. */
0284     const char *name;
0285     int index;
0286
0287     /* OOB layout description */
0288     const struct mtd_ooblayout_ops *ooblayout;
0289
0290     /* NAND pairing scheme, only provided for MLC/TLC NANDs */
0291     const struct mtd_pairing_scheme *pairing;
0292
0293     /* the ecc step size. */
0294     unsigned int ecc_step_size;
0295
0296     /* max number of correctible bit errors per ecc step */
0297     unsigned int ecc_strength;
0298
0299     /* Data for variable erase regions. If numeraseregions is zero,
0300      * it means that the whole device has erasesize as given above.
0301      */
0302     int numeraseregions;
0303     struct mtd_erase_region_info *eraseregions;
0304
0305     /*
0306      * Do not call via these pointers, use corresponding mtd_*()
0307      * wrappers instead.
0308      */
0309     int (*_erase) (struct mtd_info *mtd, struct erase_info *instr);
0310     int (*_point) (struct mtd_info *mtd, loff_t from, size_t len,
0311                size_t *retlen, void **virt, resource_size_t *phys);
0312     int (*_unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
0313     int (*_read) (struct mtd_info *mtd, loff_t from, size_t len,
0314               size_t *retlen, u_char *buf);
0315     int (*_write) (struct mtd_info *mtd, loff_t to, size_t len,
0316                size_t *retlen, const u_char *buf);
0317     int (*_panic_write) (struct mtd_info *mtd, loff_t to, size_t len,
0318                  size_t *retlen, const u_char *buf);
0319     int (*_read_oob) (struct mtd_info *mtd, loff_t from,
0320               struct mtd_oob_ops *ops);
0321     int (*_write_oob) (struct mtd_info *mtd, loff_t to,
0322                struct mtd_oob_ops *ops);
0323     int (*_get_fact_prot_info) (struct mtd_info *mtd, size_t len,
0324                     size_t *retlen, struct otp_info *buf);
0325     int (*_read_fact_prot_reg) (struct mtd_info *mtd, loff_t from,
0326                     size_t len, size_t *retlen, u_char *buf);
0327     int (*_get_user_prot_info) (struct mtd_info *mtd, size_t len,
0328                     size_t *retlen, struct otp_info *buf);
0329     int (*_read_user_prot_reg) (struct mtd_info *mtd, loff_t from,
0330                     size_t len, size_t *retlen, u_char *buf);
0331     int (*_write_user_prot_reg) (struct mtd_info *mtd, loff_t to,
0332                      size_t len, size_t *retlen,
0333                      const u_char *buf);
0334     int (*_lock_user_prot_reg) (struct mtd_info *mtd, loff_t from,
0335                     size_t len);
0336     int (*_erase_user_prot_reg) (struct mtd_info *mtd, loff_t from,
0337                      size_t len);
0338     int (*_writev) (struct mtd_info *mtd, const struct kvec *vecs,
0339             unsigned long count, loff_t to, size_t *retlen);
0340     void (*_sync) (struct mtd_info *mtd);
0341     int (*_lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
0342     int (*_unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
0343     int (*_is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
0344     int (*_block_isreserved) (struct mtd_info *mtd, loff_t ofs);
0345     int (*_block_isbad) (struct mtd_info *mtd, loff_t ofs);
0346     int (*_block_markbad) (struct mtd_info *mtd, loff_t ofs);
0347     int (*_max_bad_blocks) (struct mtd_info *mtd, loff_t ofs, size_t len);
0348     int (*_suspend) (struct mtd_info *mtd);
0349     void (*_resume) (struct mtd_info *mtd);
0350     void (*_reboot) (struct mtd_info *mtd);
0351     /*
0352      * If the driver is something smart, like UBI, it may need to maintain
0353      * its own reference counting. The below functions are only for driver.
0354      */
0355     int (*_get_device) (struct mtd_info *mtd);
0356     void (*_put_device) (struct mtd_info *mtd);
0357
0358     /*
0359      * flag indicates a panic write, low level drivers can take appropriate
0360      * action if required to ensure writes go through
0361      */
0362     bool oops_panic_write;
0363
0364     struct notifier_block reboot_notifier;  /* default mode before reboot */
0365
0366     /* ECC status information */
0367     struct mtd_ecc_stats ecc_stats;
0368     /* Subpage shift (NAND) */
0369     int subpage_sft;
0370
0371     void *priv;
0372
0373     struct module *owner;
0374     struct device dev;
0375     int usecount;
0376     struct mtd_debug_info dbg;
0377     struct nvmem_device *nvmem;
0378     struct nvmem_device *otp_user_nvmem;
0379     struct nvmem_device *otp_factory_nvmem;
0380
0381     /*
0382      * Parent device from the MTD partition point of view.
0383      *
0384      * MTD masters do not have any parent, MTD partitions do. The parent
0385      * MTD device can itself be a partition.
0386      */
0387     struct mtd_info *parent;
0388
0389     /* List of partitions attached to this MTD device */
0390     struct list_head partitions;
0391
0392     struct mtd_part part;
0393     struct mtd_master master;
0394 };
0395
0396 static inline struct mtd_info *mtd_get_master(struct mtd_info *mtd)
0397 {
0398     while (mtd->parent)
0399         mtd = mtd->parent;
0400
0401     return mtd;
0402 }
0403
0404 static inline u64 mtd_get_master_ofs(struct mtd_info *mtd, u64 ofs)
0405 {
0406     while (mtd->parent) {
0407         ofs += mtd->part.offset;
0408         mtd = mtd->parent;
0409     }
0410
0411     return ofs;
0412 }
0413
0414 static inline bool mtd_is_partition(const struct mtd_info *mtd)
0415 {
0416     return mtd->parent;
0417 }
0418
0419 static inline bool mtd_has_partitions(const struct mtd_info *mtd)
0420 {
0421     return !list_empty(&mtd->partitions);
0422 }
0423
0424 int mtd_ooblayout_ecc(struct mtd_info *mtd, int section,
0425               struct mtd_oob_region *oobecc);
0426 int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte,
0427                  int *section,
0428                  struct mtd_oob_region *oobregion);
0429 int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf,
0430                    const u8 *oobbuf, int start, int nbytes);
0431 int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf,
0432                    u8 *oobbuf, int start, int nbytes);
0433 int mtd_ooblayout_free(struct mtd_info *mtd, int section,
0434                struct mtd_oob_region *oobfree);
0435 int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf,
0436                 const u8 *oobbuf, int start, int nbytes);
0437 int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf,
0438                 u8 *oobbuf, int start, int nbytes);
0439 int mtd_ooblayout_count_freebytes(struct mtd_info *mtd);
0440 int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd);
0441
0442 static inline void mtd_set_ooblayout(struct mtd_info *mtd,
0443                      const struct mtd_ooblayout_ops *ooblayout)
0444 {
0445     mtd->ooblayout = ooblayout;
0446 }
0447
0448 static inline void mtd_set_pairing_scheme(struct mtd_info *mtd,
0449                 const struct mtd_pairing_scheme *pairing)
0450 {
0451     mtd->pairing = pairing;
0452 }
0453
0454 static inline void mtd_set_of_node(struct mtd_info *mtd,
0455                    struct device_node *np)
0456 {
0457     mtd->dev.of_node = np;
0458     if (!mtd->name)
0459         of_property_read_string(np, "label", &mtd->name);
0460 }
0461
0462 static inline struct device_node *mtd_get_of_node(struct mtd_info *mtd)
0463 {
0464     return dev_of_node(&mtd->dev);
0465 }
0466
0467 static inline u32 mtd_oobavail(struct mtd_info *mtd, struct mtd_oob_ops *ops)
0468 {
0469     return ops->mode == MTD_OPS_AUTO_OOB ? mtd->oobavail : mtd->oobsize;
0470 }
0471
0472 static inline int mtd_max_bad_blocks(struct mtd_info *mtd,
0473                      loff_t ofs, size_t len)
0474 {
0475     struct mtd_info *master = mtd_get_master(mtd);
0476
0477     if (!master->_max_bad_blocks)
0478         return -ENOTSUPP;
0479
0480     if (mtd->size < (len + ofs) || ofs < 0)
0481         return -EINVAL;
0482
0483     return master->_max_bad_blocks(master, mtd_get_master_ofs(mtd, ofs),
0484                        len);
0485 }
0486
0487 int mtd_wunit_to_pairing_info(struct mtd_info *mtd, int wunit,
0488                   struct mtd_pairing_info *info);
0489 int mtd_pairing_info_to_wunit(struct mtd_info *mtd,
0490                   const struct mtd_pairing_info *info);
0491 int mtd_pairing_groups(struct mtd_info *mtd);
0492 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr);
0493 int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
0494           void **virt, resource_size_t *phys);
0495 int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len);
0496 unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
0497                     unsigned long offset, unsigned long flags);
0498 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
0499          u_char *buf);
0500 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
0501           const u_char *buf);
0502 int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
0503             const u_char *buf);
0504
0505 int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops);
0506 int mtd_write_oob(struct mtd_info *mtd, loff_t to, struct mtd_oob_ops *ops);
0507
0508 int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
0509                struct otp_info *buf);
0510 int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
0511                size_t *retlen, u_char *buf);
0512 int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
0513                struct otp_info *buf);
0514 int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
0515                size_t *retlen, u_char *buf);
0516 int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
0517                 size_t *retlen, const u_char *buf);
0518 int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len);
0519 int mtd_erase_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len);
0520
0521 int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
0522            unsigned long count, loff_t to, size_t *retlen);
0523
0524 static inline void mtd_sync(struct mtd_info *mtd)
0525 {
0526     struct mtd_info *master = mtd_get_master(mtd);
0527
0528     if (master->_sync)
0529         master->_sync(master);
0530 }
0531
0532 int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
0533 int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
0534 int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len);
0535 int mtd_block_isreserved(struct mtd_info *mtd, loff_t ofs);
0536 int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs);
0537 int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs);
0538
0539 static inline int mtd_suspend(struct mtd_info *mtd)
0540 {
0541     struct mtd_info *master = mtd_get_master(mtd);
0542     int ret;
0543
0544     if (master->master.suspended)
0545         return 0;
0546
0547     ret = master->_suspend ? master->_suspend(master) : 0;
0548     if (ret)
0549         return ret;
0550
0551     master->master.suspended = 1;
0552     return 0;
0553 }
0554
0555 static inline void mtd_resume(struct mtd_info *mtd)
0556 {
0557     struct mtd_info *master = mtd_get_master(mtd);
0558
0559     if (!master->master.suspended)
0560         return;
0561
0562     if (master->_resume)
0563         master->_resume(master);
0564
0565     master->master.suspended = 0;
0566 }
0567
0568 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
0569 {
0570     if (mtd->erasesize_shift)
0571         return sz >> mtd->erasesize_shift;
0572     do_div(sz, mtd->erasesize);
0573     return sz;
0574 }
0575
0576 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
0577 {
0578     if (mtd->erasesize_shift)
0579         return sz & mtd->erasesize_mask;
0580     return do_div(sz, mtd->erasesize);
0581 }
0582
0583 /**
0584  * mtd_align_erase_req - Adjust an erase request to align things on eraseblock
0585  *           boundaries.
0586  * @mtd: the MTD device this erase request applies on
0587  * @req: the erase request to adjust
0588  *
0589  * This function will adjust @req->addr and @req->len to align them on
0590  * @mtd->erasesize. Of course we expect @mtd->erasesize to be != 0.
0591  */
0592 static inline void mtd_align_erase_req(struct mtd_info *mtd,
0593                        struct erase_info *req)
0594 {
0595     u32 mod;
0596
0597     if (WARN_ON(!mtd->erasesize))
0598         return;
0599
0600     mod = mtd_mod_by_eb(req->addr, mtd);
0601     if (mod) {
0602         req->addr -= mod;
0603         req->len += mod;
0604     }
0605
0606     mod = mtd_mod_by_eb(req->addr + req->len, mtd);
0607     if (mod)
0608         req->len += mtd->erasesize - mod;
0609 }
0610
0611 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
0612 {
0613     if (mtd->writesize_shift)
0614         return sz >> mtd->writesize_shift;
0615     do_div(sz, mtd->writesize);
0616     return sz;
0617 }
0618
0619 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
0620 {
0621     if (mtd->writesize_shift)
0622         return sz & mtd->writesize_mask;
0623     return do_div(sz, mtd->writesize);
0624 }
0625
0626 static inline int mtd_wunit_per_eb(struct mtd_info *mtd)
0627 {
0628     struct mtd_info *master = mtd_get_master(mtd);
0629
0630     return master->erasesize / mtd->writesize;
0631 }
0632
0633 static inline int mtd_offset_to_wunit(struct mtd_info *mtd, loff_t offs)
0634 {
0635     return mtd_div_by_ws(mtd_mod_by_eb(offs, mtd), mtd);
0636 }
0637
0638 static inline loff_t mtd_wunit_to_offset(struct mtd_info *mtd, loff_t base,
0639                      int wunit)
0640 {
0641     return base + (wunit * mtd->writesize);
0642 }
0643
0644
0645 static inline int mtd_has_oob(const struct mtd_info *mtd)
0646 {
0647     struct mtd_info *master = mtd_get_master((struct mtd_info *)mtd);
0648
0649     return master->_read_oob && master->_write_oob;
0650 }
0651
0652 static inline int mtd_type_is_nand(const struct mtd_info *mtd)
0653 {
0654     return mtd->type == MTD_NANDFLASH || mtd->type == MTD_MLCNANDFLASH;
0655 }
0656
0657 static inline int mtd_can_have_bb(const struct mtd_info *mtd)
0658 {
0659     struct mtd_info *master = mtd_get_master((struct mtd_info *)mtd);
0660
0661     return !!master->_block_isbad;
0662 }
0663
0664     /* Kernel-side ioctl definitions */
0665
0666 struct mtd_partition;
0667 struct mtd_part_parser_data;
0668
0669 extern int mtd_device_parse_register(struct mtd_info *mtd,
0670                      const char * const *part_probe_types,
0671                      struct mtd_part_parser_data *parser_data,
0672                      const struct mtd_partition *defparts,
0673                      int defnr_parts);
0674 #define mtd_device_register(master, parts, nr_parts)    \
0675     mtd_device_parse_register(master, NULL, NULL, parts, nr_parts)
0676 extern int mtd_device_unregister(struct mtd_info *master);
0677 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
0678 extern int __get_mtd_device(struct mtd_info *mtd);
0679 extern void __put_mtd_device(struct mtd_info *mtd);
0680 extern struct mtd_info *get_mtd_device_nm(const char *name);
0681 extern void put_mtd_device(struct mtd_info *mtd);
0682
0683
0684 struct mtd_notifier {
0685     void (*add)(struct mtd_info *mtd);
0686     void (*remove)(struct mtd_info *mtd);
0687     struct list_head list;
0688 };
0689
0690
0691 extern void register_mtd_user (struct mtd_notifier *new);
0692 extern int unregister_mtd_user (struct mtd_notifier *old);
0693 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size);
0694
0695 static inline int mtd_is_bitflip(int err) {
0696     return err == -EUCLEAN;
0697 }
0698
0699 static inline int mtd_is_eccerr(int err) {
0700     return err == -EBADMSG;
0701 }
0702
0703 static inline int mtd_is_bitflip_or_eccerr(int err) {
0704     return mtd_is_bitflip(err) || mtd_is_eccerr(err);
0705 }
0706
0707 unsigned mtd_mmap_capabilities(struct mtd_info *mtd);
0708
0709 #ifdef CONFIG_DEBUG_FS
0710 bool mtd_check_expert_analysis_mode(void);
0711 #else
0712 static inline bool mtd_check_expert_analysis_mode(void) { return false; }
0713 #endif
0714
0715
0716 #endif /* __MTD_MTD_H__ */