drivers/mtd/ubi/ubi.h

   1 /*
   2  * Copyright (c) International Business Machines Corp., 2006
   3  * Copyright (c) Nokia Corporation, 2006, 2007
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
  13  * the GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  18  *
  19  * Author: Artem Bityutskiy (Битюцкий Артём)
  20  */
  21
  22 #ifndef __UBI_UBI_H__
  23 #define __UBI_UBI_H__
  24
  25 #include <linux/init.h>
  26 #include <linux/types.h>
  27 #include <linux/list.h>
  28 #include <linux/rbtree.h>
  29 #include <linux/sched.h>
  30 #include <linux/wait.h>
  31 #include <linux/mutex.h>
  32 #include <linux/rwsem.h>
  33 #include <linux/spinlock.h>
  34 #include <linux/fs.h>
  35 #include <linux/cdev.h>
  36 #include <linux/device.h>
  37 #include <linux/slab.h>
  38 #include <linux/string.h>
  39 #include <linux/vmalloc.h>
  40 #include <linux/notifier.h>
  41 #include <linux/mtd/mtd.h>
  42 #include <linux/mtd/ubi.h>
  43 #include <asm/pgtable.h>
  44
  45 #include "ubi-media.h"
  46
  47 /* Maximum number of supported UBI devices */
  48 #define UBI_MAX_DEVICES 32
  49
  50 /* UBI name used for character devices, sysfs, etc */
  51 #define UBI_NAME_STR "ubi"
  52
  53 /* Normal UBI messages */
  54 #define ubi_msg(fmt, ...) printk(KERN_NOTICE "UBI: " fmt "\n", ##__VA_ARGS__)
  55 /* UBI warning messages */
  56 #define ubi_warn(fmt, ...) printk(KERN_WARNING "UBI warning: %s: " fmt "\n", \
  57                                   __func__, ##__VA_ARGS__)
  58 /* UBI error messages */
  59 #define ubi_err(fmt, ...) printk(KERN_ERR "UBI error: %s: " fmt "\n", \
  60                                  __func__, ##__VA_ARGS__)
  61
  62 /* Lowest number PEBs reserved for bad PEB handling */
  63 #define MIN_RESEVED_PEBS 2
  64
  65 /* Background thread name pattern */
  66 #define UBI_BGT_NAME_PATTERN "ubi_bgt%dd"
  67
  68 /*
  69  * This marker in the EBA table means that the LEB is um-mapped.
  70  * NOTE! It has to have the same value as %UBI_ALL.
  71  */
  72 #define UBI_LEB_UNMAPPED -1
  73
  74 /*
  75  * In case of errors, UBI tries to repeat the operation several times before
  76  * returning error. The below constant defines how many times UBI re-tries.
  77  */
  78 #define UBI_IO_RETRIES 3
  79
  80 /*
  81  * Length of the protection queue. The length is effectively equivalent to the
  82  * number of (global) erase cycles PEBs are protected from the wear-leveling
  83  * worker.
  84  */
  85 #define UBI_PROT_QUEUE_LEN 10
  86
  87 /* The volume ID/LEB number/erase counter is unknown */
  88 #define UBI_UNKNOWN -1
  89
  90 /*
  91  * Error codes returned by the I/O sub-system.
  92  *
  93  * UBI_IO_FF: the read region of flash contains only 0xFFs
  94  * UBI_IO_FF_BITFLIPS: the same as %UBI_IO_FF, but also also there was a data
  95  *                     integrity error reported by the MTD driver
  96  *                     (uncorrectable ECC error in case of NAND)
  97  * UBI_IO_BAD_HDR: the EC or VID header is corrupted (bad magic or CRC)
  98  * UBI_IO_BAD_HDR_EBADMSG: the same as %UBI_IO_BAD_HDR, but also there was a
  99  *                         data integrity error reported by the MTD driver
 100  *                         (uncorrectable ECC error in case of NAND)
 101  * UBI_IO_BITFLIPS: bit-flips were detected and corrected
 102  *
 103  * Note, it is probably better to have bit-flip and ebadmsg as flags which can
 104  * be or'ed with other error code. But this is a big change because there are
 105  * may callers, so it does not worth the risk of introducing a bug
 106  */
 107 enum {
 108         UBI_IO_FF = 1,
 109         UBI_IO_FF_BITFLIPS,
 110         UBI_IO_BAD_HDR,
 111         UBI_IO_BAD_HDR_EBADMSG,
 112         UBI_IO_BITFLIPS,
 113 };
 114
 115 /*
 116  * Return codes of the 'ubi_eba_copy_leb()' function.
 117  *
 118  * MOVE_CANCEL_RACE: canceled because the volume is being deleted, the source
 119  *                   PEB was put meanwhile, or there is I/O on the source PEB
 120  * MOVE_SOURCE_RD_ERR: canceled because there was a read error from the source
 121  *                     PEB
 122  * MOVE_TARGET_RD_ERR: canceled because there was a read error from the target
 123  *                     PEB
 124  * MOVE_TARGET_WR_ERR: canceled because there was a write error to the target
 125  *                     PEB
 126  * MOVE_TARGET_BITFLIPS: canceled because a bit-flip was detected in the
 127  *                       target PEB
 128  * MOVE_RETRY: retry scrubbing the PEB
 129  */
 130 enum {
 131         MOVE_CANCEL_RACE = 1,
 132         MOVE_SOURCE_RD_ERR,
 133         MOVE_TARGET_RD_ERR,
 134         MOVE_TARGET_WR_ERR,
 135         MOVE_TARGET_BITFLIPS,
 136         MOVE_RETRY,
 137 };
 138
 139 /**
 140  * struct ubi_wl_entry - wear-leveling entry.
 141  * @u.rb: link in the corresponding (free/used) RB-tree
 142  * @u.list: link in the protection queue
 143  * @ec: erase counter
 144  * @pnum: physical eraseblock number
 145  *
 146  * This data structure is used in the WL sub-system. Each physical eraseblock
 147  * has a corresponding &struct wl_entry object which may be kept in different
 148  * RB-trees. See WL sub-system for details.
 149  */
 150 struct ubi_wl_entry {
 151         union {
 152                 struct rb_node rb;
 153                 struct list_head list;
 154         } u;
 155         int ec;
 156         int pnum;
 157 };
 158
 159 /**
 160  * struct ubi_ltree_entry - an entry in the lock tree.
 161  * @rb: links RB-tree nodes
 162  * @vol_id: volume ID of the locked logical eraseblock
 163  * @lnum: locked logical eraseblock number
 164  * @users: how many tasks are using this logical eraseblock or wait for it
 165  * @mutex: read/write mutex to implement read/write access serialization to
 166  *         the (@vol_id, @lnum) logical eraseblock
 167  *
 168  * This data structure is used in the EBA sub-system to implement per-LEB
 169  * locking. When a logical eraseblock is being locked - corresponding
 170  * &struct ubi_ltree_entry object is inserted to the lock tree (@ubi->ltree).
 171  * See EBA sub-system for details.
 172  */
 173 struct ubi_ltree_entry {
 174         struct rb_node rb;
 175         int vol_id;
 176         int lnum;
 177         int users;
 178         struct rw_semaphore mutex;
 179 };
 180
 181 /**
 182  * struct ubi_rename_entry - volume re-name description data structure.
 183  * @new_name_len: new volume name length
 184  * @new_name: new volume name
 185  * @remove: if not zero, this volume should be removed, not re-named
 186  * @desc: descriptor of the volume
 187  * @list: links re-name entries into a list
 188  *
 189  * This data structure is utilized in the multiple volume re-name code. Namely,
 190  * UBI first creates a list of &struct ubi_rename_entry objects from the
 191  * &struct ubi_rnvol_req request object, and then utilizes this list to do all
 192  * the job.
 193  */
 194 struct ubi_rename_entry {
 195         int new_name_len;
 196         char new_name[UBI_VOL_NAME_MAX + 1];
 197         int remove;
 198         struct ubi_volume_desc *desc;
 199         struct list_head list;
 200 };
 201
 202 struct ubi_volume_desc;
 203
 204 /**
 205  * struct ubi_volume - UBI volume description data structure.
 206  * @dev: device object to make use of the the Linux device model
 207  * @cdev: character device object to create character device
 208  * @ubi: reference to the UBI device description object
 209  * @vol_id: volume ID
 210  * @ref_count: volume reference count
 211  * @readers: number of users holding this volume in read-only mode
 212  * @writers: number of users holding this volume in read-write mode
 213  * @exclusive: whether somebody holds this volume in exclusive mode
 214  *
 215  * @reserved_pebs: how many physical eraseblocks are reserved for this volume
 216  * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
 217  * @usable_leb_size: logical eraseblock size without padding
 218  * @used_ebs: how many logical eraseblocks in this volume contain data
 219  * @last_eb_bytes: how many bytes are stored in the last logical eraseblock
 220  * @used_bytes: how many bytes of data this volume contains
 221  * @alignment: volume alignment
 222  * @data_pad: how many bytes are not used at the end of physical eraseblocks to
 223  *            satisfy the requested alignment
 224  * @name_len: volume name length
 225  * @name: volume name
 226  *
 227  * @upd_ebs: how many eraseblocks are expected to be updated
 228  * @ch_lnum: LEB number which is being changing by the atomic LEB change
 229  *           operation
 230  * @upd_bytes: how many bytes are expected to be received for volume update or
 231  *             atomic LEB change
 232  * @upd_received: how many bytes were already received for volume update or
 233  *                atomic LEB change
 234  * @upd_buf: update buffer which is used to collect update data or data for
 235  *           atomic LEB change
 236  *
 237  * @eba_tbl: EBA table of this volume (LEB->PEB mapping)
 238  * @checked: %1 if this static volume was checked
 239  * @corrupted: %1 if the volume is corrupted (static volumes only)
 240  * @upd_marker: %1 if the update marker is set for this volume
 241  * @updating: %1 if the volume is being updated
 242  * @changing_leb: %1 if the atomic LEB change ioctl command is in progress
 243  * @direct_writes: %1 if direct writes are enabled for this volume
 244  *
 245  * The @corrupted field indicates that the volume's contents is corrupted.
 246  * Since UBI protects only static volumes, this field is not relevant to
 247  * dynamic volumes - it is user's responsibility to assure their data
 248  * integrity.
 249  *
 250  * The @upd_marker flag indicates that this volume is either being updated at
 251  * the moment or is damaged because of an unclean reboot.
 252  */
 253 struct ubi_volume {
 254         struct device dev;
 255         struct cdev cdev;
 256         struct ubi_device *ubi;
 257         int vol_id;
 258         int ref_count;
 259         int readers;
 260         int writers;
 261         int exclusive;
 262
 263         int reserved_pebs;
 264         int vol_type;
 265         int usable_leb_size;
 266         int used_ebs;
 267         int last_eb_bytes;
 268         long long used_bytes;
 269         int alignment;
 270         int data_pad;
 271         int name_len;
 272         char name[UBI_VOL_NAME_MAX + 1];
 273
 274         int upd_ebs;
 275         int ch_lnum;
 276         long long upd_bytes;
 277         long long upd_received;
 278         void *upd_buf;
 279
 280         int *eba_tbl;
 281         unsigned int checked:1;
 282         unsigned int corrupted:1;
 283         unsigned int upd_marker:1;
 284         unsigned int updating:1;
 285         unsigned int changing_leb:1;
 286         unsigned int direct_writes:1;
 287 };
 288
 289 /**
 290  * struct ubi_volume_desc - UBI volume descriptor returned when it is opened.
 291  * @vol: reference to the corresponding volume description object
 292  * @mode: open mode (%UBI_READONLY, %UBI_READWRITE, or %UBI_EXCLUSIVE)
 293  */
 294 struct ubi_volume_desc {
 295         struct ubi_volume *vol;
 296         int mode;
 297 };
 298
 299 struct ubi_wl_entry;
 300
 301 /**
 302  * struct ubi_device - UBI device description structure
 303  * @dev: UBI device object to use the the Linux device model
 304  * @cdev: character device object to create character device
 305  * @ubi_num: UBI device number
 306  * @ubi_name: UBI device name
 307  * @vol_count: number of volumes in this UBI device
 308  * @volumes: volumes of this UBI device
 309  * @volumes_lock: protects @volumes, @rsvd_pebs, @avail_pebs, beb_rsvd_pebs,
 310  *                @beb_rsvd_level, @bad_peb_count, @good_peb_count, @vol_count,
 311  *                @vol->readers, @vol->writers, @vol->exclusive,
 312  *                @vol->ref_count, @vol->mapping and @vol->eba_tbl.
 313  * @ref_count: count of references on the UBI device
 314  * @image_seq: image sequence number recorded on EC headers
 315  *
 316  * @rsvd_pebs: count of reserved physical eraseblocks
 317  * @avail_pebs: count of available physical eraseblocks
 318  * @beb_rsvd_pebs: how many physical eraseblocks are reserved for bad PEB
 319  *                 handling
 320  * @beb_rsvd_level: normal level of PEBs reserved for bad PEB handling
 321  *
 322  * @autoresize_vol_id: ID of the volume which has to be auto-resized at the end
 323  *                     of UBI initialization
 324  * @vtbl_slots: how many slots are available in the volume table
 325  * @vtbl_size: size of the volume table in bytes
 326  * @vtbl: in-RAM volume table copy
 327  * @device_mutex: protects on-flash volume table and serializes volume
 328  *                creation, deletion, update, re-size, re-name and set
 329  *                property
 330  *
 331  * @max_ec: current highest erase counter value
 332  * @mean_ec: current mean erase counter value
 333  *
 334  * @global_sqnum: global sequence number
 335  * @ltree_lock: protects the lock tree and @global_sqnum
 336  * @ltree: the lock tree
 337  * @alc_mutex: serializes "atomic LEB change" operations
 338  *
 339  * @used: RB-tree of used physical eraseblocks
 340  * @erroneous: RB-tree of erroneous used physical eraseblocks
 341  * @free: RB-tree of free physical eraseblocks
 342  * @scrub: RB-tree of physical eraseblocks which need scrubbing
 343  * @pq: protection queue (contain physical eraseblocks which are temporarily
 344  *      protected from the wear-leveling worker)
 345  * @pq_head: protection queue head
 346  * @wl_lock: protects the @used, @free, @pq, @pq_head, @lookuptbl, @move_from,
 347  *           @move_to, @move_to_put @erase_pending, @wl_scheduled, @works,
 348  *           @erroneous, and @erroneous_peb_count fields
 349  * @move_mutex: serializes eraseblock moves
 350  * @work_sem: synchronizes the WL worker with use tasks
 351  * @wl_scheduled: non-zero if the wear-leveling was scheduled
 352  * @lookuptbl: a table to quickly find a &struct ubi_wl_entry object for any
 353  *             physical eraseblock
 354  * @move_from: physical eraseblock from where the data is being moved
 355  * @move_to: physical eraseblock where the data is being moved to
 356  * @move_to_put: if the "to" PEB was put
 357  * @works: list of pending works
 358  * @works_count: count of pending works
 359  * @bgt_thread: background thread description object
 360  * @thread_enabled: if the background thread is enabled
 361  * @bgt_name: background thread name
 362  *
 363  * @flash_size: underlying MTD device size (in bytes)
 364  * @peb_count: count of physical eraseblocks on the MTD device
 365  * @peb_size: physical eraseblock size
 366  * @bad_peb_count: count of bad physical eraseblocks
 367  * @good_peb_count: count of good physical eraseblocks
 368  * @corr_peb_count: count of corrupted physical eraseblocks (preserved and not
 369  *                  used by UBI)
 370  * @erroneous_peb_count: count of erroneous physical eraseblocks in @erroneous
 371  * @max_erroneous: maximum allowed amount of erroneous physical eraseblocks
 372  * @min_io_size: minimal input/output unit size of the underlying MTD device
 373  * @hdrs_min_io_size: minimal I/O unit size used for VID and EC headers
 374  * @ro_mode: if the UBI device is in read-only mode
 375  * @leb_size: logical eraseblock size
 376  * @leb_start: starting offset of logical eraseblocks within physical
 377  *             eraseblocks
 378  * @ec_hdr_alsize: size of the EC header aligned to @hdrs_min_io_size
 379  * @vid_hdr_alsize: size of the VID header aligned to @hdrs_min_io_size
 380  * @vid_hdr_offset: starting offset of the volume identifier header (might be
 381  *                  unaligned)
 382  * @vid_hdr_aloffset: starting offset of the VID header aligned to
 383  * @hdrs_min_io_size
 384  * @vid_hdr_shift: contains @vid_hdr_offset - @vid_hdr_aloffset
 385  * @bad_allowed: whether the MTD device admits of bad physical eraseblocks or
 386  *               not
 387  * @nor_flash: non-zero if working on top of NOR flash
 388  * @max_write_size: maximum amount of bytes the underlying flash can write at a
 389  *                  time (MTD write buffer size)
 390  * @mtd: MTD device descriptor
 391  *
 392  * @peb_buf: a buffer of PEB size used for different purposes
 393  * @buf_mutex: protects @peb_buf
 394  * @ckvol_mutex: serializes static volume checking when opening
 395  *
 396  * @dbg: debugging information for this UBI device
 397  */
 398 struct ubi_device {
 399         struct cdev cdev;
 400         struct device dev;
 401         int ubi_num;
 402         char ubi_name[sizeof(UBI_NAME_STR)+5];
 403         int vol_count;
 404         struct ubi_volume *volumes[UBI_MAX_VOLUMES+UBI_INT_VOL_COUNT];
 405         spinlock_t volumes_lock;
 406         int ref_count;
 407         int image_seq;
 408
 409         int rsvd_pebs;
 410         int avail_pebs;
 411         int beb_rsvd_pebs;
 412         int beb_rsvd_level;
 413
 414         int autoresize_vol_id;
 415         int vtbl_slots;
 416         int vtbl_size;
 417         struct ubi_vtbl_record *vtbl;
 418         struct mutex device_mutex;
 419
 420         int max_ec;
 421         /* Note, mean_ec is not updated run-time - should be fixed */
 422         int mean_ec;
 423
 424         /* EBA sub-system's stuff */
 425         unsigned long long global_sqnum;
 426         spinlock_t ltree_lock;
 427         struct rb_root ltree;
 428         struct mutex alc_mutex;
 429
 430         /* Wear-leveling sub-system's stuff */
 431         struct rb_root used;
 432         struct rb_root erroneous;
 433         struct rb_root free;
 434         struct rb_root scrub;
 435         struct list_head pq[UBI_PROT_QUEUE_LEN];
 436         int pq_head;
 437         spinlock_t wl_lock;
 438         struct mutex move_mutex;
 439         struct rw_semaphore work_sem;
 440         int wl_scheduled;
 441         struct ubi_wl_entry **lookuptbl;
 442         struct ubi_wl_entry *move_from;
 443         struct ubi_wl_entry *move_to;
 444         int move_to_put;
 445         struct list_head works;
 446         int works_count;
 447         struct task_struct *bgt_thread;
 448         int thread_enabled;
 449         char bgt_name[sizeof(UBI_BGT_NAME_PATTERN)+2];
 450
 451         /* I/O sub-system's stuff */
 452         long long flash_size;
 453         int peb_count;
 454         int peb_size;
 455         int bad_peb_count;
 456         int good_peb_count;
 457         int corr_peb_count;
 458         int erroneous_peb_count;
 459         int max_erroneous;
 460         int min_io_size;
 461         int hdrs_min_io_size;
 462         int ro_mode;
 463         int leb_size;
 464         int leb_start;
 465         int ec_hdr_alsize;
 466         int vid_hdr_alsize;
 467         int vid_hdr_offset;
 468         int vid_hdr_aloffset;
 469         int vid_hdr_shift;
 470         unsigned int bad_allowed:1;
 471         unsigned int nor_flash:1;
 472         int max_write_size;
 473         struct mtd_info *mtd;
 474
 475         void *peb_buf;
 476         struct mutex buf_mutex;
 477         struct mutex ckvol_mutex;
 478
 479         struct ubi_debug_info *dbg;
 480 };
 481
 482 /**
 483  * struct ubi_ainf_peb - attach information about a physical eraseblock.
 484  * @ec: erase counter (%UBI_UNKNOWN if it is unknown)
 485  * @pnum: physical eraseblock number
 486  * @vol_id: ID of the volume this LEB belongs to
 487  * @lnum: logical eraseblock number
 488  * @scrub: if this physical eraseblock needs scrubbing
 489  * @copy_flag: this LEB is a copy (@copy_flag is set in VID header of this LEB)
 490  * @sqnum: sequence number
 491  * @u: unions RB-tree or @list links
 492  * @u.rb: link in the per-volume RB-tree of &struct ubi_ainf_peb objects
 493  * @u.list: link in one of the eraseblock lists
 494  *
 495  * One object of this type is allocated for each physical eraseblock when
 496  * attaching an MTD device. Note, if this PEB does not belong to any LEB /
 497  * volume, the @vol_id and @lnum fields are initialized to %UBI_UNKNOWN.
 498  */
 499 struct ubi_ainf_peb {
 500         int ec;
 501         int pnum;
 502         int vol_id;
 503         int lnum;
 504         unsigned int scrub:1;
 505         unsigned int copy_flag:1;
 506         unsigned long long sqnum;
 507         union {
 508                 struct rb_node rb;
 509                 struct list_head list;
 510         } u;
 511 };
 512
 513 /**
 514  * struct ubi_ainf_volume - attaching information about a volume.
 515  * @vol_id: volume ID
 516  * @highest_lnum: highest logical eraseblock number in this volume
 517  * @leb_count: number of logical eraseblocks in this volume
 518  * @vol_type: volume type
 519  * @used_ebs: number of used logical eraseblocks in this volume (only for
 520  *            static volumes)
 521  * @last_data_size: amount of data in the last logical eraseblock of this
 522  *                  volume (always equivalent to the usable logical eraseblock
 523  *                  size in case of dynamic volumes)
 524  * @data_pad: how many bytes at the end of logical eraseblocks of this volume
 525  *            are not used (due to volume alignment)
 526  * @compat: compatibility flags of this volume
 527  * @rb: link in the volume RB-tree
 528  * @root: root of the RB-tree containing all the eraseblock belonging to this
 529  *        volume (&struct ubi_ainf_peb objects)
 530  *
 531  * One object of this type is allocated for each volume when attaching an MTD
 532  * device.
 533  */
 534 struct ubi_ainf_volume {
 535         int vol_id;
 536         int highest_lnum;
 537         int leb_count;
 538         int vol_type;
 539         int used_ebs;
 540         int last_data_size;
 541         int data_pad;
 542         int compat;
 543         struct rb_node rb;
 544         struct rb_root root;
 545 };
 546
 547 /**
 548  * struct ubi_attach_info - MTD device attaching information.
 549  * @volumes: root of the volume RB-tree
 550  * @corr: list of corrupted physical eraseblocks
 551  * @free: list of free physical eraseblocks
 552  * @erase: list of physical eraseblocks which have to be erased
 553  * @alien: list of physical eraseblocks which should not be used by UBI (e.g.,
 554  *         those belonging to "preserve"-compatible internal volumes)
 555  * @corr_peb_count: count of PEBs in the @corr list
 556  * @empty_peb_count: count of PEBs which are presumably empty (contain only
 557  *                   0xFF bytes)
 558  * @alien_peb_count: count of PEBs in the @alien list
 559  * @bad_peb_count: count of bad physical eraseblocks
 560  * @maybe_bad_peb_count: count of bad physical eraseblocks which are not marked
 561  *                       as bad yet, but which look like bad
 562  * @vols_found: number of volumes found
 563  * @highest_vol_id: highest volume ID
 564  * @is_empty: flag indicating whether the MTD device is empty or not
 565  * @min_ec: lowest erase counter value
 566  * @max_ec: highest erase counter value
 567  * @max_sqnum: highest sequence number value
 568  * @mean_ec: mean erase counter value
 569  * @ec_sum: a temporary variable used when calculating @mean_ec
 570  * @ec_count: a temporary variable used when calculating @mean_ec
 571  * @aeb_slab_cache: slab cache for &struct ubi_ainf_peb objects
 572  *
 573  * This data structure contains the result of attaching an MTD device and may
 574  * be used by other UBI sub-systems to build final UBI data structures, further
 575  * error-recovery and so on.
 576  */
 577 struct ubi_attach_info {
 578         struct rb_root volumes;
 579         struct list_head corr;
 580         struct list_head free;
 581         struct list_head erase;
 582         struct list_head alien;
 583         int corr_peb_count;
 584         int empty_peb_count;
 585         int alien_peb_count;
 586         int bad_peb_count;
 587         int maybe_bad_peb_count;
 588         int vols_found;
 589         int highest_vol_id;
 590         int is_empty;
 591         int min_ec;
 592         int max_ec;
 593         unsigned long long max_sqnum;
 594         int mean_ec;
 595         uint64_t ec_sum;
 596         int ec_count;
 597         struct kmem_cache *aeb_slab_cache;
 598 };
 599
 600 #include "debug.h"
 601
 602 extern struct kmem_cache *ubi_wl_entry_slab;
 603 extern const struct file_operations ubi_ctrl_cdev_operations;
 604 extern const struct file_operations ubi_cdev_operations;
 605 extern const struct file_operations ubi_vol_cdev_operations;
 606 extern struct class *ubi_class;
 607 extern struct mutex ubi_devices_mutex;
 608 extern struct blocking_notifier_head ubi_notifiers;
 609
 610 /* scan.c */
 611 int ubi_add_to_av(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum,
 612                   int ec, const struct ubi_vid_hdr *vid_hdr, int bitflips);
 613 struct ubi_ainf_volume *ubi_find_av(const struct ubi_attach_info *ai,
 614                                     int vol_id);
 615 void ubi_remove_av(struct ubi_attach_info *ai, struct ubi_ainf_volume *av);
 616 struct ubi_ainf_peb *ubi_early_get_peb(struct ubi_device *ubi,
 617                                        struct ubi_attach_info *ai);
 618 int ubi_attach(struct ubi_device *ubi);
 619 void ubi_destroy_ai(struct ubi_attach_info *ai);
 620
 621 /* vtbl.c */
 622 int ubi_change_vtbl_record(struct ubi_device *ubi, int idx,
 623                            struct ubi_vtbl_record *vtbl_rec);
 624 int ubi_vtbl_rename_volumes(struct ubi_device *ubi,
 625                             struct list_head *rename_list);
 626 int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_attach_info *ai);
 627
 628 /* vmt.c */
 629 int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req);
 630 int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl);
 631 int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs);
 632 int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list);
 633 int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol);
 634 void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol);
 635
 636 /* upd.c */
 637 int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol,
 638                      long long bytes);
 639 int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol,
 640                          const void __user *buf, int count);
 641 int ubi_start_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
 642                          const struct ubi_leb_change_req *req);
 643 int ubi_more_leb_change_data(struct ubi_device *ubi, struct ubi_volume *vol,
 644                              const void __user *buf, int count);
 645
 646 /* misc.c */
 647 int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf,
 648                       int length);
 649 int ubi_check_volume(struct ubi_device *ubi, int vol_id);
 650 void ubi_update_reserved(struct ubi_device *ubi);
 651 void ubi_calculate_reserved(struct ubi_device *ubi);
 652 int ubi_check_pattern(const void *buf, uint8_t patt, int size);
 653
 654 /* eba.c */
 655 int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol,
 656                       int lnum);
 657 int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
 658                      void *buf, int offset, int len, int check);
 659 int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
 660                       const void *buf, int offset, int len);
 661 int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol,
 662                          int lnum, const void *buf, int len, int used_ebs);
 663 int ubi_eba_atomic_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
 664                               int lnum, const void *buf, int len);
 665 int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
 666                      struct ubi_vid_hdr *vid_hdr);
 667 int ubi_eba_init(struct ubi_device *ubi, struct ubi_attach_info *ai);
 668
 669 /* wl.c */
 670 int ubi_wl_get_peb(struct ubi_device *ubi);
 671 int ubi_wl_put_peb(struct ubi_device *ubi, int vol_id, int lnum,
 672                    int pnum, int torture);
 673 int ubi_wl_flush(struct ubi_device *ubi, int vol_id, int lnum);
 674 int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum);
 675 int ubi_wl_init(struct ubi_device *ubi, struct ubi_attach_info *ai);
 676 void ubi_wl_close(struct ubi_device *ubi);
 677 int ubi_thread(void *u);
 678
 679 /* io.c */
 680 int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset,
 681                 int len);
 682 int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
 683                  int len);
 684 int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture);
 685 int ubi_io_is_bad(const struct ubi_device *ubi, int pnum);
 686 int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum);
 687 int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum,
 688                        struct ubi_ec_hdr *ec_hdr, int verbose);
 689 int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum,
 690                         struct ubi_ec_hdr *ec_hdr);
 691 int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum,
 692                         struct ubi_vid_hdr *vid_hdr, int verbose);
 693 int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum,
 694                          struct ubi_vid_hdr *vid_hdr);
 695
 696 /* build.c */
 697 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset);
 698 int ubi_detach_mtd_dev(int ubi_num, int anyway);
 699 struct ubi_device *ubi_get_device(int ubi_num);
 700 void ubi_put_device(struct ubi_device *ubi);
 701 struct ubi_device *ubi_get_by_major(int major);
 702 int ubi_major2num(int major);
 703 int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol,
 704                       int ntype);
 705 int ubi_notify_all(struct ubi_device *ubi, int ntype,
 706                    struct notifier_block *nb);
 707 int ubi_enumerate_volumes(struct notifier_block *nb);
 708 void ubi_free_internal_volumes(struct ubi_device *ubi);
 709
 710 /* kapi.c */
 711 void ubi_do_get_device_info(struct ubi_device *ubi, struct ubi_device_info *di);
 712 void ubi_do_get_volume_info(struct ubi_device *ubi, struct ubi_volume *vol,
 713                             struct ubi_volume_info *vi);
 714
 715 /*
 716  * ubi_rb_for_each_entry - walk an RB-tree.
 717  * @rb: a pointer to type 'struct rb_node' to use as a loop counter
 718  * @pos: a pointer to RB-tree entry type to use as a loop counter
 719  * @root: RB-tree's root
 720  * @member: the name of the 'struct rb_node' within the RB-tree entry
 721  */
 722 #define ubi_rb_for_each_entry(rb, pos, root, member)                         \
 723         for (rb = rb_first(root),                                            \
 724              pos = (rb ? container_of(rb, typeof(*pos), member) : NULL);     \
 725              rb;                                                             \
 726              rb = rb_next(rb),                                               \
 727              pos = (rb ? container_of(rb, typeof(*pos), member) : NULL))
 728
 729 /*
 730  * ubi_move_aeb_to_list - move a PEB from the volume tree to a list.
 731  *
 732  * @av: volume attaching information
 733  * @aeb: attaching eraseblock information
 734  * @list: the list to move to
 735  */
 736 static inline void ubi_move_aeb_to_list(struct ubi_ainf_volume *av,
 737                                          struct ubi_ainf_peb *aeb,
 738                                          struct list_head *list)
 739 {
 740                 rb_erase(&aeb->u.rb, &av->root);
 741                 list_add_tail(&aeb->u.list, list);
 742 }
 743
 744 /**
 745  * ubi_zalloc_vid_hdr - allocate a volume identifier header object.
 746  * @ubi: UBI device description object
 747  * @gfp_flags: GFP flags to allocate with
 748  *
 749  * This function returns a pointer to the newly allocated and zero-filled
 750  * volume identifier header object in case of success and %NULL in case of
 751  * failure.
 752  */
 753 static inline struct ubi_vid_hdr *
 754 ubi_zalloc_vid_hdr(const struct ubi_device *ubi, gfp_t gfp_flags)
 755 {
 756         void *vid_hdr;
 757
 758         vid_hdr = kzalloc(ubi->vid_hdr_alsize, gfp_flags);
 759         if (!vid_hdr)
 760                 return NULL;
 761
 762         /*
 763          * VID headers may be stored at un-aligned flash offsets, so we shift
 764          * the pointer.
 765          */
 766         return vid_hdr + ubi->vid_hdr_shift;
 767 }
 768
 769 /**
 770  * ubi_free_vid_hdr - free a volume identifier header object.
 771  * @ubi: UBI device description object
 772  * @vid_hdr: the object to free
 773  */
 774 static inline void ubi_free_vid_hdr(const struct ubi_device *ubi,
 775                                     struct ubi_vid_hdr *vid_hdr)
 776 {
 777         void *p = vid_hdr;
 778
 779         if (!p)
 780                 return;
 781
 782         kfree(p - ubi->vid_hdr_shift);
 783 }
 784
 785 /*
 786  * This function is equivalent to 'ubi_io_read()', but @offset is relative to
 787  * the beginning of the logical eraseblock, not to the beginning of the
 788  * physical eraseblock.
 789  */
 790 static inline int ubi_io_read_data(const struct ubi_device *ubi, void *buf,
 791                                    int pnum, int offset, int len)
 792 {
 793         ubi_assert(offset >= 0);
 794         return ubi_io_read(ubi, buf, pnum, offset + ubi->leb_start, len);
 795 }
 796
 797 /*
 798  * This function is equivalent to 'ubi_io_write()', but @offset is relative to
 799  * the beginning of the logical eraseblock, not to the beginning of the
 800  * physical eraseblock.
 801  */
 802 static inline int ubi_io_write_data(struct ubi_device *ubi, const void *buf,
 803                                     int pnum, int offset, int len)
 804 {
 805         ubi_assert(offset >= 0);
 806         return ubi_io_write(ubi, buf, pnum, offset + ubi->leb_start, len);
 807 }
 808
 809 /**
 810  * ubi_ro_mode - switch to read-only mode.
 811  * @ubi: UBI device description object
 812  */
 813 static inline void ubi_ro_mode(struct ubi_device *ubi)
 814 {
 815         if (!ubi->ro_mode) {
 816                 ubi->ro_mode = 1;
 817                 ubi_warn("switch to read-only mode");
 818                 dump_stack();
 819         }
 820 }
 821
 822 /**
 823  * vol_id2idx - get table index by volume ID.
 824  * @ubi: UBI device description object
 825  * @vol_id: volume ID
 826  */
 827 static inline int vol_id2idx(const struct ubi_device *ubi, int vol_id)
 828 {
 829         if (vol_id >= UBI_INTERNAL_VOL_START)
 830                 return vol_id - UBI_INTERNAL_VOL_START + ubi->vtbl_slots;
 831         else
 832                 return vol_id;
 833 }
 834
 835 /**
 836  * idx2vol_id - get volume ID by table index.
 837  * @ubi: UBI device description object
 838  * @idx: table index
 839  */
 840 static inline int idx2vol_id(const struct ubi_device *ubi, int idx)
 841 {
 842         if (idx >= ubi->vtbl_slots)
 843                 return idx - ubi->vtbl_slots + UBI_INTERNAL_VOL_START;
 844         else
 845                 return idx;
 846 }
 847
 848 #endif /* !__UBI_UBI_H__ */