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/string.h>
  38 #include <linux/vmalloc.h>
  39 #include <linux/mtd/mtd.h>
  40 #include <linux/mtd/ubi.h>
  41
  42 #include "ubi-media.h"
  43 #include "scan.h"
  44 #include "debug.h"
  45
  46 /* Maximum number of supported UBI devices */
  47 #define UBI_MAX_DEVICES 32
  48
  49 /* UBI name used for character devices, sysfs, etc */
  50 #define UBI_NAME_STR "ubi"
  51
  52 /* Normal UBI messages */
  53 #define ubi_msg(fmt, ...) printk(KERN_NOTICE "UBI: " fmt "\n", ##__VA_ARGS__)
  54 /* UBI warning messages */
  55 #define ubi_warn(fmt, ...) printk(KERN_WARNING "UBI warning: %s: " fmt "\n", \
  56                                   __func__, ##__VA_ARGS__)
  57 /* UBI error messages */
  58 #define ubi_err(fmt, ...) printk(KERN_ERR "UBI error: %s: " fmt "\n", \
  59                                  __func__, ##__VA_ARGS__)
  60
  61 /* Lowest number PEBs reserved for bad PEB handling */
  62 #define MIN_RESEVED_PEBS 2
  63
  64 /* Background thread name pattern */
  65 #define UBI_BGT_NAME_PATTERN "ubi_bgt%dd"
  66
  67 /* This marker in the EBA table means that the LEB is um-mapped */
  68 #define UBI_LEB_UNMAPPED -1
  69
  70 /*
  71  * In case of errors, UBI tries to repeat the operation several times before
  72  * returning error. The below constant defines how many times UBI re-tries.
  73  */
  74 #define UBI_IO_RETRIES 3
  75
  76 /*
  77  * Error codes returned by the I/O sub-system.
  78  *
  79  * UBI_IO_PEB_EMPTY: the physical eraseblock is empty, i.e. it contains only
  80  *                   %0xFF bytes
  81  * UBI_IO_PEB_FREE: the physical eraseblock is free, i.e. it contains only a
  82  *                  valid erase counter header, and the rest are %0xFF bytes
  83  * UBI_IO_BAD_EC_HDR: the erase counter header is corrupted (bad magic or CRC)
  84  * UBI_IO_BAD_VID_HDR: the volume identifier header is corrupted (bad magic or
  85  *                     CRC)
  86  * UBI_IO_BITFLIPS: bit-flips were detected and corrected
  87  */
  88 enum {
  89         UBI_IO_PEB_EMPTY = 1,
  90         UBI_IO_PEB_FREE,
  91         UBI_IO_BAD_EC_HDR,
  92         UBI_IO_BAD_VID_HDR,
  93         UBI_IO_BITFLIPS
  94 };
  95
  96 /**
  97  * struct ubi_wl_entry - wear-leveling entry.
  98  * @rb: link in the corresponding RB-tree
  99  * @ec: erase counter
 100  * @pnum: physical eraseblock number
 101  *
 102  * This data structure is used in the WL sub-system. Each physical eraseblock
 103  * has a corresponding &struct wl_entry object which may be kept in different
 104  * RB-trees. See WL sub-system for details.
 105  */
 106 struct ubi_wl_entry {
 107         struct rb_node rb;
 108         int ec;
 109         int pnum;
 110 };
 111
 112 /**
 113  * struct ubi_ltree_entry - an entry in the lock tree.
 114  * @rb: links RB-tree nodes
 115  * @vol_id: volume ID of the locked logical eraseblock
 116  * @lnum: locked logical eraseblock number
 117  * @users: how many tasks are using this logical eraseblock or wait for it
 118  * @mutex: read/write mutex to implement read/write access serialization to
 119  *         the (@vol_id, @lnum) logical eraseblock
 120  *
 121  * This data structure is used in the EBA sub-system to implement per-LEB
 122  * locking. When a logical eraseblock is being locked - corresponding
 123  * &struct ubi_ltree_entry object is inserted to the lock tree (@ubi->ltree).
 124  * See EBA sub-system for details.
 125  */
 126 struct ubi_ltree_entry {
 127         struct rb_node rb;
 128         int vol_id;
 129         int lnum;
 130         int users;
 131         struct rw_semaphore mutex;
 132 };
 133
 134 /**
 135  * struct ubi_rename_entry - volume re-name description data structure.
 136  * @new_name_len: new volume name length
 137  * @new_name: new volume name
 138  * @remove: if not zero, this volume should be removed, not re-named
 139  * @desc: descriptor of the volume
 140  * @list: links re-name entries into a list
 141  *
 142  * This data structure is utilized in the multiple volume re-name code. Namely,
 143  * UBI first creates a list of &struct ubi_rename_entry objects from the
 144  * &struct ubi_rnvol_req request object, and then utilizes this list to do all
 145  * the job.
 146  */
 147 struct ubi_rename_entry {
 148         int new_name_len;
 149         char new_name[UBI_VOL_NAME_MAX + 1];
 150         int remove;
 151         struct ubi_volume_desc *desc;
 152         struct list_head list;
 153 };
 154
 155 struct ubi_volume_desc;
 156
 157 /**
 158  * struct ubi_volume - UBI volume description data structure.
 159  * @dev: device object to make use of the the Linux device model
 160  * @cdev: character device object to create character device
 161  * @ubi: reference to the UBI device description object
 162  * @vol_id: volume ID
 163  * @ref_count: volume reference count
 164  * @readers: number of users holding this volume in read-only mode
 165  * @writers: number of users holding this volume in read-write mode
 166  * @exclusive: whether somebody holds this volume in exclusive mode
 167  *
 168  * @reserved_pebs: how many physical eraseblocks are reserved for this volume
 169  * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
 170  * @usable_leb_size: logical eraseblock size without padding
 171  * @used_ebs: how many logical eraseblocks in this volume contain data
 172  * @last_eb_bytes: how many bytes are stored in the last logical eraseblock
 173  * @used_bytes: how many bytes of data this volume contains
 174  * @alignment: volume alignment
 175  * @data_pad: how many bytes are not used at the end of physical eraseblocks to
 176  *            satisfy the requested alignment
 177  * @name_len: volume name length
 178  * @name: volume name
 179  *
 180  * @upd_ebs: how many eraseblocks are expected to be updated
 181  * @ch_lnum: LEB number which is being changing by the atomic LEB change
 182  *           operation
 183  * @ch_dtype: data persistency type which is being changing by the atomic LEB
 184  *            change operation
 185  * @upd_bytes: how many bytes are expected to be received for volume update or
 186  *             atomic LEB change
 187  * @upd_received: how many bytes were already received for volume update or
 188  *                atomic LEB change
 189  * @upd_buf: update buffer which is used to collect update data or data for
 190  *           atomic LEB change
 191  *
 192  * @eba_tbl: EBA table of this volume (LEB->PEB mapping)
 193  * @checked: %1 if this static volume was checked
 194  * @corrupted: %1 if the volume is corrupted (static volumes only)
 195  * @upd_marker: %1 if the update marker is set for this volume
 196  * @updating: %1 if the volume is being updated
 197  * @changing_leb: %1 if the atomic LEB change ioctl command is in progress
 198  *
 199  * @gluebi_desc: gluebi UBI volume descriptor
 200  * @gluebi_refcount: reference count of the gluebi MTD device
 201  * @gluebi_mtd: MTD device description object of the gluebi MTD device
 202  *
 203  * The @corrupted field indicates that the volume's contents is corrupted.
 204  * Since UBI protects only static volumes, this field is not relevant to
 205  * dynamic volumes - it is user's responsibility to assure their data
 206  * integrity.
 207  *
 208  * The @upd_marker flag indicates that this volume is either being updated at
 209  * the moment or is damaged because of an unclean reboot.
 210  */
 211 struct ubi_volume {
 212         struct device dev;
 213         struct cdev cdev;
 214         struct ubi_device *ubi;
 215         int vol_id;
 216         int ref_count;
 217         int readers;
 218         int writers;
 219         int exclusive;
 220
 221         int reserved_pebs;
 222         int vol_type;
 223         int usable_leb_size;
 224         int used_ebs;
 225         int last_eb_bytes;
 226         long long used_bytes;
 227         int alignment;
 228         int data_pad;
 229         int name_len;
 230         char name[UBI_VOL_NAME_MAX + 1];
 231
 232         int upd_ebs;
 233         int ch_lnum;
 234         int ch_dtype;
 235         long long upd_bytes;
 236         long long upd_received;
 237         void *upd_buf;
 238
 239         int *eba_tbl;
 240         unsigned int checked:1;
 241         unsigned int corrupted:1;
 242         unsigned int upd_marker:1;
 243         unsigned int updating:1;
 244         unsigned int changing_leb:1;
 245
 246 #ifdef CONFIG_MTD_UBI_GLUEBI
 247         /*
 248          * Gluebi-related stuff may be compiled out.
 249          * Note: this should not be built into UBI but should be a separate
 250          * ubimtd driver which works on top of UBI and emulates MTD devices.
 251          */
 252         struct ubi_volume_desc *gluebi_desc;
 253         int gluebi_refcount;
 254         struct mtd_info gluebi_mtd;
 255 #endif
 256 };
 257
 258 /**
 259  * struct ubi_volume_desc - UBI volume descriptor returned when it is opened.
 260  * @vol: reference to the corresponding volume description object
 261  * @mode: open mode (%UBI_READONLY, %UBI_READWRITE, or %UBI_EXCLUSIVE)
 262  */
 263 struct ubi_volume_desc {
 264         struct ubi_volume *vol;
 265         int mode;
 266 };
 267
 268 struct ubi_wl_entry;
 269
 270 /**
 271  * struct ubi_device - UBI device description structure
 272  * @dev: UBI device object to use the the Linux device model
 273  * @cdev: character device object to create character device
 274  * @ubi_num: UBI device number
 275  * @ubi_name: UBI device name
 276  * @vol_count: number of volumes in this UBI device
 277  * @volumes: volumes of this UBI device
 278  * @volumes_lock: protects @volumes, @rsvd_pebs, @avail_pebs, beb_rsvd_pebs,
 279  *                @beb_rsvd_level, @bad_peb_count, @good_peb_count, @vol_count,
 280  *                @vol->readers, @vol->writers, @vol->exclusive,
 281  *                @vol->ref_count, @vol->mapping and @vol->eba_tbl.
 282  * @ref_count: count of references on the UBI device
 283  *
 284  * @rsvd_pebs: count of reserved physical eraseblocks
 285  * @avail_pebs: count of available physical eraseblocks
 286  * @beb_rsvd_pebs: how many physical eraseblocks are reserved for bad PEB
 287  *                 handling
 288  * @beb_rsvd_level: normal level of PEBs reserved for bad PEB handling
 289  *
 290  * @autoresize_vol_id: ID of the volume which has to be auto-resized at the end
 291  *                     of UBI ititializetion
 292  * @vtbl_slots: how many slots are available in the volume table
 293  * @vtbl_size: size of the volume table in bytes
 294  * @vtbl: in-RAM volume table copy
 295  * @volumes_mutex: protects on-flash volume table and serializes volume
 296  *                 changes, like creation, deletion, update, re-size and re-name
 297  *
 298  * @max_ec: current highest erase counter value
 299  * @mean_ec: current mean erase counter value
 300  *
 301  * @global_sqnum: global sequence number
 302  * @ltree_lock: protects the lock tree and @global_sqnum
 303  * @ltree: the lock tree
 304  * @alc_mutex: serializes "atomic LEB change" operations
 305  *
 306  * @used: RB-tree of used physical eraseblocks
 307  * @free: RB-tree of free physical eraseblocks
 308  * @scrub: RB-tree of physical eraseblocks which need scrubbing
 309  * @prot: protection trees
 310  * @prot.pnum: protection tree indexed by physical eraseblock numbers
 311  * @prot.aec: protection tree indexed by absolute erase counter value
 312  * @wl_lock: protects the @used, @free, @prot, @lookuptbl, @abs_ec, @move_from,
 313  *           @move_to, @move_to_put @erase_pending, @wl_scheduled, and @works
 314  *           fields
 315  * @move_mutex: serializes eraseblock moves
 316  * @work_sem: sycnhronizes the WL worker with use tasks
 317  * @wl_scheduled: non-zero if the wear-leveling was scheduled
 318  * @lookuptbl: a table to quickly find a &struct ubi_wl_entry object for any
 319  *             physical eraseblock
 320  * @abs_ec: absolute erase counter
 321  * @move_from: physical eraseblock from where the data is being moved
 322  * @move_to: physical eraseblock where the data is being moved to
 323  * @move_to_put: if the "to" PEB was put
 324  * @works: list of pending works
 325  * @works_count: count of pending works
 326  * @bgt_thread: background thread description object
 327  * @thread_enabled: if the background thread is enabled
 328  * @bgt_name: background thread name
 329  *
 330  * @flash_size: underlying MTD device size (in bytes)
 331  * @peb_count: count of physical eraseblocks on the MTD device
 332  * @peb_size: physical eraseblock size
 333  * @bad_peb_count: count of bad physical eraseblocks
 334  * @good_peb_count: count of good physical eraseblocks
 335  * @min_io_size: minimal input/output unit size of the underlying MTD device
 336  * @hdrs_min_io_size: minimal I/O unit size used for VID and EC headers
 337  * @ro_mode: if the UBI device is in read-only mode
 338  * @leb_size: logical eraseblock size
 339  * @leb_start: starting offset of logical eraseblocks within physical
 340  *             eraseblocks
 341  * @ec_hdr_alsize: size of the EC header aligned to @hdrs_min_io_size
 342  * @vid_hdr_alsize: size of the VID header aligned to @hdrs_min_io_size
 343  * @vid_hdr_offset: starting offset of the volume identifier header (might be
 344  *                  unaligned)
 345  * @vid_hdr_aloffset: starting offset of the VID header aligned to
 346  * @hdrs_min_io_size
 347  * @vid_hdr_shift: contains @vid_hdr_offset - @vid_hdr_aloffset
 348  * @bad_allowed: whether the MTD device admits of bad physical eraseblocks or
 349  *               not
 350  * @mtd: MTD device descriptor
 351  *
 352  * @peb_buf1: a buffer of PEB size used for different purposes
 353  * @peb_buf2: another buffer of PEB size used for different purposes
 354  * @buf_mutex: proptects @peb_buf1 and @peb_buf2
 355  * @ckvol_mutex: serializes static volume checking when opening
 356  * @mult_mutex: serializes operations on multiple volumes, like re-nameing
 357  * @dbg_peb_buf: buffer of PEB size used for debugging
 358  * @dbg_buf_mutex: proptects @dbg_peb_buf
 359  */
 360 struct ubi_device {
 361         struct cdev cdev;
 362         struct device dev;
 363         int ubi_num;
 364         char ubi_name[sizeof(UBI_NAME_STR)+5];
 365         int vol_count;
 366         struct ubi_volume *volumes[UBI_MAX_VOLUMES+UBI_INT_VOL_COUNT];
 367         spinlock_t volumes_lock;
 368         int ref_count;
 369
 370         int rsvd_pebs;
 371         int avail_pebs;
 372         int beb_rsvd_pebs;
 373         int beb_rsvd_level;
 374
 375         int autoresize_vol_id;
 376         int vtbl_slots;
 377         int vtbl_size;
 378         struct ubi_vtbl_record *vtbl;
 379         struct mutex volumes_mutex;
 380
 381         int max_ec;
 382         /* Note, mean_ec is not updated run-time - should be fixed */
 383         int mean_ec;
 384
 385         /* EBA sub-system's stuff */
 386         unsigned long long global_sqnum;
 387         spinlock_t ltree_lock;
 388         struct rb_root ltree;
 389         struct mutex alc_mutex;
 390
 391         /* Wear-leveling sub-system's stuff */
 392         struct rb_root used;
 393         struct rb_root free;
 394         struct rb_root scrub;
 395         struct {
 396                 struct rb_root pnum;
 397                 struct rb_root aec;
 398         } prot;
 399         spinlock_t wl_lock;
 400         struct mutex move_mutex;
 401         struct rw_semaphore work_sem;
 402         int wl_scheduled;
 403         struct ubi_wl_entry **lookuptbl;
 404         unsigned long long abs_ec;
 405         struct ubi_wl_entry *move_from;
 406         struct ubi_wl_entry *move_to;
 407         int move_to_put;
 408         struct list_head works;
 409         int works_count;
 410         struct task_struct *bgt_thread;
 411         int thread_enabled;
 412         char bgt_name[sizeof(UBI_BGT_NAME_PATTERN)+2];
 413
 414         /* I/O sub-system's stuff */
 415         long long flash_size;
 416         int peb_count;
 417         int peb_size;
 418         int bad_peb_count;
 419         int good_peb_count;
 420         int min_io_size;
 421         int hdrs_min_io_size;
 422         int ro_mode;
 423         int leb_size;
 424         int leb_start;
 425         int ec_hdr_alsize;
 426         int vid_hdr_alsize;
 427         int vid_hdr_offset;
 428         int vid_hdr_aloffset;
 429         int vid_hdr_shift;
 430         int bad_allowed;
 431         struct mtd_info *mtd;
 432
 433         void *peb_buf1;
 434         void *peb_buf2;
 435         struct mutex buf_mutex;
 436         struct mutex ckvol_mutex;
 437         struct mutex mult_mutex;
 438 #ifdef CONFIG_MTD_UBI_DEBUG
 439         void *dbg_peb_buf;
 440         struct mutex dbg_buf_mutex;
 441 #endif
 442 };
 443
 444 extern struct kmem_cache *ubi_wl_entry_slab;
 445 extern struct file_operations ubi_ctrl_cdev_operations;
 446 extern struct file_operations ubi_cdev_operations;
 447 extern struct file_operations ubi_vol_cdev_operations;
 448 extern struct class *ubi_class;
 449 extern struct mutex ubi_devices_mutex;
 450
 451 /* vtbl.c */
 452 int ubi_change_vtbl_record(struct ubi_device *ubi, int idx,
 453                            struct ubi_vtbl_record *vtbl_rec);
 454 int ubi_vtbl_rename_volumes(struct ubi_device *ubi,
 455                             struct list_head *rename_list);
 456 int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_scan_info *si);
 457
 458 /* vmt.c */
 459 int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req);
 460 int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl);
 461 int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs);
 462 int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list);
 463 int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol);
 464 void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol);
 465
 466 /* upd.c */
 467 int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol,
 468                      long long bytes);
 469 int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol,
 470                          const void __user *buf, int count);
 471 int ubi_start_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
 472                          const struct ubi_leb_change_req *req);
 473 int ubi_more_leb_change_data(struct ubi_device *ubi, struct ubi_volume *vol,
 474                              const void __user *buf, int count);
 475
 476 /* misc.c */
 477 int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf,
 478                       int length);
 479 int ubi_check_volume(struct ubi_device *ubi, int vol_id);
 480 void ubi_calculate_reserved(struct ubi_device *ubi);
 481
 482 /* gluebi.c */
 483 #ifdef CONFIG_MTD_UBI_GLUEBI
 484 int ubi_create_gluebi(struct ubi_device *ubi, struct ubi_volume *vol);
 485 int ubi_destroy_gluebi(struct ubi_volume *vol);
 486 void ubi_gluebi_updated(struct ubi_volume *vol);
 487 #else
 488 #define ubi_create_gluebi(ubi, vol) 0
 489 #define ubi_destroy_gluebi(vol) 0
 490 #define ubi_gluebi_updated(vol)
 491 #endif
 492
 493 /* eba.c */
 494 int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol,
 495                       int lnum);
 496 int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
 497                      void *buf, int offset, int len, int check);
 498 int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
 499                       const void *buf, int offset, int len, int dtype);
 500 int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol,
 501                          int lnum, const void *buf, int len, int dtype,
 502                          int used_ebs);
 503 int ubi_eba_atomic_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
 504                               int lnum, const void *buf, int len, int dtype);
 505 int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
 506                      struct ubi_vid_hdr *vid_hdr);
 507 int ubi_eba_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si);
 508
 509 /* wl.c */
 510 int ubi_wl_get_peb(struct ubi_device *ubi, int dtype);
 511 int ubi_wl_put_peb(struct ubi_device *ubi, int pnum, int torture);
 512 int ubi_wl_flush(struct ubi_device *ubi);
 513 int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum);
 514 int ubi_wl_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si);
 515 void ubi_wl_close(struct ubi_device *ubi);
 516 int ubi_thread(void *u);
 517
 518 /* io.c */
 519 int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset,
 520                 int len);
 521 int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
 522                  int len);
 523 int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture);
 524 int ubi_io_is_bad(const struct ubi_device *ubi, int pnum);
 525 int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum);
 526 int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum,
 527                        struct ubi_ec_hdr *ec_hdr, int verbose);
 528 int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum,
 529                         struct ubi_ec_hdr *ec_hdr);
 530 int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum,
 531                         struct ubi_vid_hdr *vid_hdr, int verbose);
 532 int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum,
 533                          struct ubi_vid_hdr *vid_hdr);
 534
 535 /* build.c */
 536 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset);
 537 int ubi_detach_mtd_dev(int ubi_num, int anyway);
 538 struct ubi_device *ubi_get_device(int ubi_num);
 539 void ubi_put_device(struct ubi_device *ubi);
 540 struct ubi_device *ubi_get_by_major(int major);
 541 int ubi_major2num(int major);
 542
 543 /*
 544  * ubi_rb_for_each_entry - walk an RB-tree.
 545  * @rb: a pointer to type 'struct rb_node' to to use as a loop counter
 546  * @pos: a pointer to RB-tree entry type to use as a loop counter
 547  * @root: RB-tree's root
 548  * @member: the name of the 'struct rb_node' within the RB-tree entry
 549  */
 550 #define ubi_rb_for_each_entry(rb, pos, root, member)                         \
 551         for (rb = rb_first(root),                                            \
 552              pos = (rb ? container_of(rb, typeof(*pos), member) : NULL);     \
 553              rb;                                                             \
 554              rb = rb_next(rb), pos = container_of(rb, typeof(*pos), member))
 555
 556 /**
 557  * ubi_zalloc_vid_hdr - allocate a volume identifier header object.
 558  * @ubi: UBI device description object
 559  * @gfp_flags: GFP flags to allocate with
 560  *
 561  * This function returns a pointer to the newly allocated and zero-filled
 562  * volume identifier header object in case of success and %NULL in case of
 563  * failure.
 564  */
 565 static inline struct ubi_vid_hdr *
 566 ubi_zalloc_vid_hdr(const struct ubi_device *ubi, gfp_t gfp_flags)
 567 {
 568         void *vid_hdr;
 569
 570         vid_hdr = kzalloc(ubi->vid_hdr_alsize, gfp_flags);
 571         if (!vid_hdr)
 572                 return NULL;
 573
 574         /*
 575          * VID headers may be stored at un-aligned flash offsets, so we shift
 576          * the pointer.
 577          */
 578         return vid_hdr + ubi->vid_hdr_shift;
 579 }
 580
 581 /**
 582  * ubi_free_vid_hdr - free a volume identifier header object.
 583  * @ubi: UBI device description object
 584  * @vid_hdr: the object to free
 585  */
 586 static inline void ubi_free_vid_hdr(const struct ubi_device *ubi,
 587                                     struct ubi_vid_hdr *vid_hdr)
 588 {
 589         void *p = vid_hdr;
 590
 591         if (!p)
 592                 return;
 593
 594         kfree(p - ubi->vid_hdr_shift);
 595 }
 596
 597 /*
 598  * This function is equivalent to 'ubi_io_read()', but @offset is relative to
 599  * the beginning of the logical eraseblock, not to the beginning of the
 600  * physical eraseblock.
 601  */
 602 static inline int ubi_io_read_data(const struct ubi_device *ubi, void *buf,
 603                                    int pnum, int offset, int len)
 604 {
 605         ubi_assert(offset >= 0);
 606         return ubi_io_read(ubi, buf, pnum, offset + ubi->leb_start, len);
 607 }
 608
 609 /*
 610  * This function is equivalent to 'ubi_io_write()', but @offset is relative to
 611  * the beginning of the logical eraseblock, not to the beginning of the
 612  * physical eraseblock.
 613  */
 614 static inline int ubi_io_write_data(struct ubi_device *ubi, const void *buf,
 615                                     int pnum, int offset, int len)
 616 {
 617         ubi_assert(offset >= 0);
 618         return ubi_io_write(ubi, buf, pnum, offset + ubi->leb_start, len);
 619 }
 620
 621 /**
 622  * ubi_ro_mode - switch to read-only mode.
 623  * @ubi: UBI device description object
 624  */
 625 static inline void ubi_ro_mode(struct ubi_device *ubi)
 626 {
 627         if (!ubi->ro_mode) {
 628                 ubi->ro_mode = 1;
 629                 ubi_warn("switch to read-only mode");
 630         }
 631 }
 632
 633 /**
 634  * vol_id2idx - get table index by volume ID.
 635  * @ubi: UBI device description object
 636  * @vol_id: volume ID
 637  */
 638 static inline int vol_id2idx(const struct ubi_device *ubi, int vol_id)
 639 {
 640         if (vol_id >= UBI_INTERNAL_VOL_START)
 641                 return vol_id - UBI_INTERNAL_VOL_START + ubi->vtbl_slots;
 642         else
 643                 return vol_id;
 644 }
 645
 646 /**
 647  * idx2vol_id - get volume ID by table index.
 648  * @ubi: UBI device description object
 649  * @idx: table index
 650  */
 651 static inline int idx2vol_id(const struct ubi_device *ubi, int idx)
 652 {
 653         if (idx >= ubi->vtbl_slots)
 654                 return idx - ubi->vtbl_slots + UBI_INTERNAL_VOL_START;
 655         else
 656                 return idx;
 657 }
 658
 659 #endif /* !__UBI_UBI_H__ */