cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
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mtd.h (22597B)


      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/**
     76 * struct mtd_oob_region - oob region definition
     77 * @offset: region offset
     78 * @length: region length
     79 *
     80 * This structure describes a region of the OOB area, and is used
     81 * to retrieve ECC or free bytes sections.
     82 * Each section is defined by an offset within the OOB area and a
     83 * length.
     84 */
     85struct mtd_oob_region {
     86	u32 offset;
     87	u32 length;
     88};
     89
     90/*
     91 * struct mtd_ooblayout_ops - NAND OOB layout operations
     92 * @ecc: function returning an ECC region in the OOB area.
     93 *	 Should return -ERANGE if %section exceeds the total number of
     94 *	 ECC sections.
     95 * @free: function returning a free region in the OOB area.
     96 *	  Should return -ERANGE if %section exceeds the total number of
     97 *	  free sections.
     98 */
     99struct mtd_ooblayout_ops {
    100	int (*ecc)(struct mtd_info *mtd, int section,
    101		   struct mtd_oob_region *oobecc);
    102	int (*free)(struct mtd_info *mtd, int section,
    103		    struct mtd_oob_region *oobfree);
    104};
    105
    106/**
    107 * struct mtd_pairing_info - page pairing information
    108 *
    109 * @pair: pair id
    110 * @group: group id
    111 *
    112 * The term "pair" is used here, even though TLC NANDs might group pages by 3
    113 * (3 bits in a single cell). A pair should regroup all pages that are sharing
    114 * the same cell. Pairs are then indexed in ascending order.
    115 *
    116 * @group is defining the position of a page in a given pair. It can also be
    117 * seen as the bit position in the cell: page attached to bit 0 belongs to
    118 * group 0, page attached to bit 1 belongs to group 1, etc.
    119 *
    120 * Example:
    121 * The H27UCG8T2BTR-BC datasheet describes the following pairing scheme:
    122 *
    123 *		group-0		group-1
    124 *
    125 *  pair-0	page-0		page-4
    126 *  pair-1	page-1		page-5
    127 *  pair-2	page-2		page-8
    128 *  ...
    129 *  pair-127	page-251	page-255
    130 *
    131 *
    132 * Note that the "group" and "pair" terms were extracted from Samsung and
    133 * Hynix datasheets, and might be referenced under other names in other
    134 * datasheets (Micron is describing this concept as "shared pages").
    135 */
    136struct mtd_pairing_info {
    137	int pair;
    138	int group;
    139};
    140
    141/**
    142 * struct mtd_pairing_scheme - page pairing scheme description
    143 *
    144 * @ngroups: number of groups. Should be related to the number of bits
    145 *	     per cell.
    146 * @get_info: converts a write-unit (page number within an erase block) into
    147 *	      mtd_pairing information (pair + group). This function should
    148 *	      fill the info parameter based on the wunit index or return
    149 *	      -EINVAL if the wunit parameter is invalid.
    150 * @get_wunit: converts pairing information into a write-unit (page) number.
    151 *	       This function should return the wunit index pointed by the
    152 *	       pairing information described in the info argument. It should
    153 *	       return -EINVAL, if there's no wunit corresponding to the
    154 *	       passed pairing information.
    155 *
    156 * See mtd_pairing_info documentation for a detailed explanation of the
    157 * pair and group concepts.
    158 *
    159 * The mtd_pairing_scheme structure provides a generic solution to represent
    160 * NAND page pairing scheme. Instead of exposing two big tables to do the
    161 * write-unit <-> (pair + group) conversions, we ask the MTD drivers to
    162 * implement the ->get_info() and ->get_wunit() functions.
    163 *
    164 * MTD users will then be able to query these information by using the
    165 * mtd_pairing_info_to_wunit() and mtd_wunit_to_pairing_info() helpers.
    166 *
    167 * @ngroups is here to help MTD users iterating over all the pages in a
    168 * given pair. This value can be retrieved by MTD users using the
    169 * mtd_pairing_groups() helper.
    170 *
    171 * Examples are given in the mtd_pairing_info_to_wunit() and
    172 * mtd_wunit_to_pairing_info() documentation.
    173 */
    174struct mtd_pairing_scheme {
    175	int ngroups;
    176	int (*get_info)(struct mtd_info *mtd, int wunit,
    177			struct mtd_pairing_info *info);
    178	int (*get_wunit)(struct mtd_info *mtd,
    179			 const struct mtd_pairing_info *info);
    180};
    181
    182struct module;	/* only needed for owner field in mtd_info */
    183
    184/**
    185 * struct mtd_debug_info - debugging information for an MTD device.
    186 *
    187 * @dfs_dir: direntry object of the MTD device debugfs directory
    188 */
    189struct mtd_debug_info {
    190	struct dentry *dfs_dir;
    191};
    192
    193/**
    194 * struct mtd_part - MTD partition specific fields
    195 *
    196 * @node: list node used to add an MTD partition to the parent partition list
    197 * @offset: offset of the partition relatively to the parent offset
    198 * @size: partition size. Should be equal to mtd->size unless
    199 *	  MTD_SLC_ON_MLC_EMULATION is set
    200 * @flags: original flags (before the mtdpart logic decided to tweak them based
    201 *	   on flash constraints, like eraseblock/pagesize alignment)
    202 *
    203 * This struct is embedded in mtd_info and contains partition-specific
    204 * properties/fields.
    205 */
    206struct mtd_part {
    207	struct list_head node;
    208	u64 offset;
    209	u64 size;
    210	u32 flags;
    211};
    212
    213/**
    214 * struct mtd_master - MTD master specific fields
    215 *
    216 * @partitions_lock: lock protecting accesses to the partition list. Protects
    217 *		     not only the master partition list, but also all
    218 *		     sub-partitions.
    219 * @suspended: et to 1 when the device is suspended, 0 otherwise
    220 *
    221 * This struct is embedded in mtd_info and contains master-specific
    222 * properties/fields. The master is the root MTD device from the MTD partition
    223 * point of view.
    224 */
    225struct mtd_master {
    226	struct mutex partitions_lock;
    227	struct mutex chrdev_lock;
    228	unsigned int suspended : 1;
    229};
    230
    231struct mtd_info {
    232	u_char type;
    233	uint32_t flags;
    234	uint64_t size;	 // Total size of the MTD
    235
    236	/* "Major" erase size for the device. Naïve users may take this
    237	 * to be the only erase size available, or may use the more detailed
    238	 * information below if they desire
    239	 */
    240	uint32_t erasesize;
    241	/* Minimal writable flash unit size. In case of NOR flash it is 1 (even
    242	 * though individual bits can be cleared), in case of NAND flash it is
    243	 * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
    244	 * it is of ECC block size, etc. It is illegal to have writesize = 0.
    245	 * Any driver registering a struct mtd_info must ensure a writesize of
    246	 * 1 or larger.
    247	 */
    248	uint32_t writesize;
    249
    250	/*
    251	 * Size of the write buffer used by the MTD. MTD devices having a write
    252	 * buffer can write multiple writesize chunks at a time. E.g. while
    253	 * writing 4 * writesize bytes to a device with 2 * writesize bytes
    254	 * buffer the MTD driver can (but doesn't have to) do 2 writesize
    255	 * operations, but not 4. Currently, all NANDs have writebufsize
    256	 * equivalent to writesize (NAND page size). Some NOR flashes do have
    257	 * writebufsize greater than writesize.
    258	 */
    259	uint32_t writebufsize;
    260
    261	uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)
    262	uint32_t oobavail;  // Available OOB bytes per block
    263
    264	/*
    265	 * If erasesize is a power of 2 then the shift is stored in
    266	 * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
    267	 */
    268	unsigned int erasesize_shift;
    269	unsigned int writesize_shift;
    270	/* Masks based on erasesize_shift and writesize_shift */
    271	unsigned int erasesize_mask;
    272	unsigned int writesize_mask;
    273
    274	/*
    275	 * read ops return -EUCLEAN if max number of bitflips corrected on any
    276	 * one region comprising an ecc step equals or exceeds this value.
    277	 * Settable by driver, else defaults to ecc_strength.  User can override
    278	 * in sysfs.  N.B. The meaning of the -EUCLEAN return code has changed;
    279	 * see Documentation/ABI/testing/sysfs-class-mtd for more detail.
    280	 */
    281	unsigned int bitflip_threshold;
    282
    283	/* Kernel-only stuff starts here. */
    284	const char *name;
    285	int index;
    286
    287	/* OOB layout description */
    288	const struct mtd_ooblayout_ops *ooblayout;
    289
    290	/* NAND pairing scheme, only provided for MLC/TLC NANDs */
    291	const struct mtd_pairing_scheme *pairing;
    292
    293	/* the ecc step size. */
    294	unsigned int ecc_step_size;
    295
    296	/* max number of correctible bit errors per ecc step */
    297	unsigned int ecc_strength;
    298
    299	/* Data for variable erase regions. If numeraseregions is zero,
    300	 * it means that the whole device has erasesize as given above.
    301	 */
    302	int numeraseregions;
    303	struct mtd_erase_region_info *eraseregions;
    304
    305	/*
    306	 * Do not call via these pointers, use corresponding mtd_*()
    307	 * wrappers instead.
    308	 */
    309	int (*_erase) (struct mtd_info *mtd, struct erase_info *instr);
    310	int (*_point) (struct mtd_info *mtd, loff_t from, size_t len,
    311		       size_t *retlen, void **virt, resource_size_t *phys);
    312	int (*_unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
    313	int (*_read) (struct mtd_info *mtd, loff_t from, size_t len,
    314		      size_t *retlen, u_char *buf);
    315	int (*_write) (struct mtd_info *mtd, loff_t to, size_t len,
    316		       size_t *retlen, const u_char *buf);
    317	int (*_panic_write) (struct mtd_info *mtd, loff_t to, size_t len,
    318			     size_t *retlen, const u_char *buf);
    319	int (*_read_oob) (struct mtd_info *mtd, loff_t from,
    320			  struct mtd_oob_ops *ops);
    321	int (*_write_oob) (struct mtd_info *mtd, loff_t to,
    322			   struct mtd_oob_ops *ops);
    323	int (*_get_fact_prot_info) (struct mtd_info *mtd, size_t len,
    324				    size_t *retlen, struct otp_info *buf);
    325	int (*_read_fact_prot_reg) (struct mtd_info *mtd, loff_t from,
    326				    size_t len, size_t *retlen, u_char *buf);
    327	int (*_get_user_prot_info) (struct mtd_info *mtd, size_t len,
    328				    size_t *retlen, struct otp_info *buf);
    329	int (*_read_user_prot_reg) (struct mtd_info *mtd, loff_t from,
    330				    size_t len, size_t *retlen, u_char *buf);
    331	int (*_write_user_prot_reg) (struct mtd_info *mtd, loff_t to,
    332				     size_t len, size_t *retlen,
    333				     const u_char *buf);
    334	int (*_lock_user_prot_reg) (struct mtd_info *mtd, loff_t from,
    335				    size_t len);
    336	int (*_erase_user_prot_reg) (struct mtd_info *mtd, loff_t from,
    337				     size_t len);
    338	int (*_writev) (struct mtd_info *mtd, const struct kvec *vecs,
    339			unsigned long count, loff_t to, size_t *retlen);
    340	void (*_sync) (struct mtd_info *mtd);
    341	int (*_lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
    342	int (*_unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
    343	int (*_is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
    344	int (*_block_isreserved) (struct mtd_info *mtd, loff_t ofs);
    345	int (*_block_isbad) (struct mtd_info *mtd, loff_t ofs);
    346	int (*_block_markbad) (struct mtd_info *mtd, loff_t ofs);
    347	int (*_max_bad_blocks) (struct mtd_info *mtd, loff_t ofs, size_t len);
    348	int (*_suspend) (struct mtd_info *mtd);
    349	void (*_resume) (struct mtd_info *mtd);
    350	void (*_reboot) (struct mtd_info *mtd);
    351	/*
    352	 * If the driver is something smart, like UBI, it may need to maintain
    353	 * its own reference counting. The below functions are only for driver.
    354	 */
    355	int (*_get_device) (struct mtd_info *mtd);
    356	void (*_put_device) (struct mtd_info *mtd);
    357
    358	/*
    359	 * flag indicates a panic write, low level drivers can take appropriate
    360	 * action if required to ensure writes go through
    361	 */
    362	bool oops_panic_write;
    363
    364	struct notifier_block reboot_notifier;  /* default mode before reboot */
    365
    366	/* ECC status information */
    367	struct mtd_ecc_stats ecc_stats;
    368	/* Subpage shift (NAND) */
    369	int subpage_sft;
    370
    371	void *priv;
    372
    373	struct module *owner;
    374	struct device dev;
    375	int usecount;
    376	struct mtd_debug_info dbg;
    377	struct nvmem_device *nvmem;
    378	struct nvmem_device *otp_user_nvmem;
    379	struct nvmem_device *otp_factory_nvmem;
    380
    381	/*
    382	 * Parent device from the MTD partition point of view.
    383	 *
    384	 * MTD masters do not have any parent, MTD partitions do. The parent
    385	 * MTD device can itself be a partition.
    386	 */
    387	struct mtd_info *parent;
    388
    389	/* List of partitions attached to this MTD device */
    390	struct list_head partitions;
    391
    392	struct mtd_part part;
    393	struct mtd_master master;
    394};
    395
    396static inline struct mtd_info *mtd_get_master(struct mtd_info *mtd)
    397{
    398	while (mtd->parent)
    399		mtd = mtd->parent;
    400
    401	return mtd;
    402}
    403
    404static inline u64 mtd_get_master_ofs(struct mtd_info *mtd, u64 ofs)
    405{
    406	while (mtd->parent) {
    407		ofs += mtd->part.offset;
    408		mtd = mtd->parent;
    409	}
    410
    411	return ofs;
    412}
    413
    414static inline bool mtd_is_partition(const struct mtd_info *mtd)
    415{
    416	return mtd->parent;
    417}
    418
    419static inline bool mtd_has_partitions(const struct mtd_info *mtd)
    420{
    421	return !list_empty(&mtd->partitions);
    422}
    423
    424int mtd_ooblayout_ecc(struct mtd_info *mtd, int section,
    425		      struct mtd_oob_region *oobecc);
    426int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte,
    427				 int *section,
    428				 struct mtd_oob_region *oobregion);
    429int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf,
    430			       const u8 *oobbuf, int start, int nbytes);
    431int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf,
    432			       u8 *oobbuf, int start, int nbytes);
    433int mtd_ooblayout_free(struct mtd_info *mtd, int section,
    434		       struct mtd_oob_region *oobfree);
    435int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf,
    436				const u8 *oobbuf, int start, int nbytes);
    437int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf,
    438				u8 *oobbuf, int start, int nbytes);
    439int mtd_ooblayout_count_freebytes(struct mtd_info *mtd);
    440int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd);
    441
    442static inline void mtd_set_ooblayout(struct mtd_info *mtd,
    443				     const struct mtd_ooblayout_ops *ooblayout)
    444{
    445	mtd->ooblayout = ooblayout;
    446}
    447
    448static inline void mtd_set_pairing_scheme(struct mtd_info *mtd,
    449				const struct mtd_pairing_scheme *pairing)
    450{
    451	mtd->pairing = pairing;
    452}
    453
    454static inline void mtd_set_of_node(struct mtd_info *mtd,
    455				   struct device_node *np)
    456{
    457	mtd->dev.of_node = np;
    458	if (!mtd->name)
    459		of_property_read_string(np, "label", &mtd->name);
    460}
    461
    462static inline struct device_node *mtd_get_of_node(struct mtd_info *mtd)
    463{
    464	return dev_of_node(&mtd->dev);
    465}
    466
    467static inline u32 mtd_oobavail(struct mtd_info *mtd, struct mtd_oob_ops *ops)
    468{
    469	return ops->mode == MTD_OPS_AUTO_OOB ? mtd->oobavail : mtd->oobsize;
    470}
    471
    472static inline int mtd_max_bad_blocks(struct mtd_info *mtd,
    473				     loff_t ofs, size_t len)
    474{
    475	struct mtd_info *master = mtd_get_master(mtd);
    476
    477	if (!master->_max_bad_blocks)
    478		return -ENOTSUPP;
    479
    480	if (mtd->size < (len + ofs) || ofs < 0)
    481		return -EINVAL;
    482
    483	return master->_max_bad_blocks(master, mtd_get_master_ofs(mtd, ofs),
    484				       len);
    485}
    486
    487int mtd_wunit_to_pairing_info(struct mtd_info *mtd, int wunit,
    488			      struct mtd_pairing_info *info);
    489int mtd_pairing_info_to_wunit(struct mtd_info *mtd,
    490			      const struct mtd_pairing_info *info);
    491int mtd_pairing_groups(struct mtd_info *mtd);
    492int mtd_erase(struct mtd_info *mtd, struct erase_info *instr);
    493int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
    494	      void **virt, resource_size_t *phys);
    495int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len);
    496unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
    497				    unsigned long offset, unsigned long flags);
    498int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
    499	     u_char *buf);
    500int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
    501	      const u_char *buf);
    502int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
    503		    const u_char *buf);
    504
    505int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops);
    506int mtd_write_oob(struct mtd_info *mtd, loff_t to, struct mtd_oob_ops *ops);
    507
    508int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
    509			   struct otp_info *buf);
    510int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
    511			   size_t *retlen, u_char *buf);
    512int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
    513			   struct otp_info *buf);
    514int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
    515			   size_t *retlen, u_char *buf);
    516int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
    517			    size_t *retlen, const u_char *buf);
    518int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len);
    519int mtd_erase_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#ifdef CONFIG_DEBUG_FS
    710bool mtd_check_expert_analysis_mode(void);
    711#else
    712static inline bool mtd_check_expert_analysis_mode(void) { return false; }
    713#endif
    714
    715
    716#endif /* __MTD_MTD_H__ */