1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * Copyright (c) International Business Machines Corp., 2006
4 * Copyright (c) Nokia Corporation, 2006, 2007
5 *
6 * Author: Artem Bityutskiy (���������������� ����������)
7 */
8
9#ifndef __UBI_UBI_H__
10#define __UBI_UBI_H__
11
12#include <linux/types.h>
13#include <linux/list.h>
14#include <linux/rbtree.h>
15#include <linux/sched.h>
16#include <linux/wait.h>
17#include <linux/mutex.h>
18#include <linux/rwsem.h>
19#include <linux/spinlock.h>
20#include <linux/fs.h>
21#include <linux/cdev.h>
22#include <linux/device.h>
23#include <linux/slab.h>
24#include <linux/string.h>
25#include <linux/vmalloc.h>
26#include <linux/notifier.h>
27#include <linux/mtd/mtd.h>
28#include <linux/mtd/ubi.h>
29#include <linux/pgtable.h>
30
31#include "ubi-media.h"
32
33/* Maximum number of supported UBI devices */
34#define UBI_MAX_DEVICES 32
35
36/* UBI name used for character devices, sysfs, etc */
37#define UBI_NAME_STR "ubi"
38
39struct ubi_device;
40
41/* Normal UBI messages */
42__printf(2, 3)
43void ubi_msg(const struct ubi_device *ubi, const char *fmt, ...);
44
45/* UBI warning messages */
46__printf(2, 3)
47void ubi_warn(const struct ubi_device *ubi, const char *fmt, ...);
48
49/* UBI error messages */
50__printf(2, 3)
51void ubi_err(const struct ubi_device *ubi, const char *fmt, ...);
52
53/* Background thread name pattern */
54#define UBI_BGT_NAME_PATTERN "ubi_bgt%dd"
55
56/*
57 * This marker in the EBA table means that the LEB is um-mapped.
58 * NOTE! It has to have the same value as %UBI_ALL.
59 */
60#define UBI_LEB_UNMAPPED -1
61
62/*
63 * In case of errors, UBI tries to repeat the operation several times before
64 * returning error. The below constant defines how many times UBI re-tries.
65 */
66#define UBI_IO_RETRIES 3
67
68/*
69 * Length of the protection queue. The length is effectively equivalent to the
70 * number of (global) erase cycles PEBs are protected from the wear-leveling
71 * worker.
72 */
73#define UBI_PROT_QUEUE_LEN 10
74
75/* The volume ID/LEB number/erase counter is unknown */
76#define UBI_UNKNOWN -1
77
78/*
79 * The UBI debugfs directory name pattern and maximum name length (3 for "ubi"
80 * + 2 for the number plus 1 for the trailing zero byte.
81 */
82#define UBI_DFS_DIR_NAME "ubi%d"
83#define UBI_DFS_DIR_LEN  (3 + 2 + 1)
84
85/* Number of physical eraseblocks reserved for atomic LEB change operation */
86#define EBA_RESERVED_PEBS 1
87
88/*
89 * Error codes returned by the I/O sub-system.
90 *
91 * UBI_IO_FF: the read region of flash contains only 0xFFs
92 * UBI_IO_FF_BITFLIPS: the same as %UBI_IO_FF, but also there was a data
93 *                     integrity error reported by the MTD driver
94 *                     (uncorrectable ECC error in case of NAND)
95 * UBI_IO_BAD_HDR: the EC or VID header is corrupted (bad magic or CRC)
96 * UBI_IO_BAD_HDR_EBADMSG: the same as %UBI_IO_BAD_HDR, but also there was a
97 *                         data integrity error reported by the MTD driver
98 *                         (uncorrectable ECC error in case of NAND)
99 * UBI_IO_BITFLIPS: bit-flips were detected and corrected
100 *
101 * Note, it is probably better to have bit-flip and ebadmsg as flags which can
102 * be or'ed with other error code. But this is a big change because there are
103 * may callers, so it does not worth the risk of introducing a bug
104 */
105enum {
106	UBI_IO_FF = 1,
107	UBI_IO_FF_BITFLIPS,
108	UBI_IO_BAD_HDR,
109	UBI_IO_BAD_HDR_EBADMSG,
110	UBI_IO_BITFLIPS,
111};
112
113/*
114 * Return codes of the 'ubi_eba_copy_leb()' function.
115 *
116 * MOVE_CANCEL_RACE: canceled because the volume is being deleted, the source
117 *                   PEB was put meanwhile, or there is I/O on the source PEB
118 * MOVE_SOURCE_RD_ERR: canceled because there was a read error from the source
119 *                     PEB
120 * MOVE_TARGET_RD_ERR: canceled because there was a read error from the target
121 *                     PEB
122 * MOVE_TARGET_WR_ERR: canceled because there was a write error to the target
123 *                     PEB
124 * MOVE_TARGET_BITFLIPS: canceled because a bit-flip was detected in the
125 *                       target PEB
126 * MOVE_RETRY: retry scrubbing the PEB
127 */
128enum {
129	MOVE_CANCEL_RACE = 1,
130	MOVE_SOURCE_RD_ERR,
131	MOVE_TARGET_RD_ERR,
132	MOVE_TARGET_WR_ERR,
133	MOVE_TARGET_BITFLIPS,
134	MOVE_RETRY,
135};
136
137/*
138 * Return codes of the fastmap sub-system
139 *
140 * UBI_NO_FASTMAP: No fastmap super block was found
141 * UBI_BAD_FASTMAP: A fastmap was found but it's unusable
142 */
143enum {
144	UBI_NO_FASTMAP = 1,
145	UBI_BAD_FASTMAP,
146};
147
148/**
149 * struct ubi_vid_io_buf - VID buffer used to read/write VID info to/from the
150 *			   flash.
151 * @hdr: a pointer to the VID header stored in buffer
152 * @buffer: underlying buffer
153 */
154struct ubi_vid_io_buf {
155	struct ubi_vid_hdr *hdr;
156	void *buffer;
157};
158
159/**
160 * struct ubi_wl_entry - wear-leveling entry.
161 * @u.rb: link in the corresponding (free/used) RB-tree
162 * @u.list: link in the protection queue
163 * @ec: erase counter
164 * @pnum: physical eraseblock number
165 *
166 * This data structure is used in the WL sub-system. Each physical eraseblock
167 * has a corresponding &struct wl_entry object which may be kept in different
168 * RB-trees. See WL sub-system for details.
169 */
170struct ubi_wl_entry {
171	union {
172		struct rb_node rb;
173		struct list_head list;
174	} u;
175	int ec;
176	int pnum;
177};
178
179/**
180 * struct ubi_ltree_entry - an entry in the lock tree.
181 * @rb: links RB-tree nodes
182 * @vol_id: volume ID of the locked logical eraseblock
183 * @lnum: locked logical eraseblock number
184 * @users: how many tasks are using this logical eraseblock or wait for it
185 * @mutex: read/write mutex to implement read/write access serialization to
186 *         the (@vol_id, @lnum) logical eraseblock
187 *
188 * This data structure is used in the EBA sub-system to implement per-LEB
189 * locking. When a logical eraseblock is being locked - corresponding
190 * &struct ubi_ltree_entry object is inserted to the lock tree (@ubi->ltree).
191 * See EBA sub-system for details.
192 */
193struct ubi_ltree_entry {
194	struct rb_node rb;
195	int vol_id;
196	int lnum;
197	int users;
198	struct rw_semaphore mutex;
199};
200
201/**
202 * struct ubi_rename_entry - volume re-name description data structure.
203 * @new_name_len: new volume name length
204 * @new_name: new volume name
205 * @remove: if not zero, this volume should be removed, not re-named
206 * @desc: descriptor of the volume
207 * @list: links re-name entries into a list
208 *
209 * This data structure is utilized in the multiple volume re-name code. Namely,
210 * UBI first creates a list of &struct ubi_rename_entry objects from the
211 * &struct ubi_rnvol_req request object, and then utilizes this list to do all
212 * the job.
213 */
214struct ubi_rename_entry {
215	int new_name_len;
216	char new_name[UBI_VOL_NAME_MAX + 1];
217	int remove;
218	struct ubi_volume_desc *desc;
219	struct list_head list;
220};
221
222struct ubi_volume_desc;
223
224/**
225 * struct ubi_fastmap_layout - in-memory fastmap data structure.
226 * @e: PEBs used by the current fastmap
227 * @to_be_tortured: if non-zero tortured this PEB
228 * @used_blocks: number of used PEBs
229 * @max_pool_size: maximal size of the user pool
230 * @max_wl_pool_size: maximal size of the pool used by the WL sub-system
231 */
232struct ubi_fastmap_layout {
233	struct ubi_wl_entry *e[UBI_FM_MAX_BLOCKS];
234	int to_be_tortured[UBI_FM_MAX_BLOCKS];
235	int used_blocks;
236	int max_pool_size;
237	int max_wl_pool_size;
238};
239
240/**
241 * struct ubi_fm_pool - in-memory fastmap pool
242 * @pebs: PEBs in this pool
243 * @used: number of used PEBs
244 * @size: total number of PEBs in this pool
245 * @max_size: maximal size of the pool
246 *
247 * A pool gets filled with up to max_size.
248 * If all PEBs within the pool are used a new fastmap will be written
249 * to the flash and the pool gets refilled with empty PEBs.
250 *
251 */
252struct ubi_fm_pool {
253	int pebs[UBI_FM_MAX_POOL_SIZE];
254	int used;
255	int size;
256	int max_size;
257};
258
259/**
260 * struct ubi_eba_leb_desc - EBA logical eraseblock descriptor
261 * @lnum: the logical eraseblock number
262 * @pnum: the physical eraseblock where the LEB can be found
263 *
264 * This structure is here to hide EBA's internal from other part of the
265 * UBI implementation.
266 *
267 * One can query the position of a LEB by calling ubi_eba_get_ldesc().
268 */
269struct ubi_eba_leb_desc {
270	int lnum;
271	int pnum;
272};
273
274/**
275 * struct ubi_volume - UBI volume description data structure.
276 * @dev: device object to make use of the Linux device model
277 * @cdev: character device object to create character device
278 * @ubi: reference to the UBI device description object
279 * @vol_id: volume ID
280 * @ref_count: volume reference count
281 * @readers: number of users holding this volume in read-only mode
282 * @writers: number of users holding this volume in read-write mode
283 * @exclusive: whether somebody holds this volume in exclusive mode
284 * @metaonly: whether somebody is altering only meta data of this volume
285 *
286 * @reserved_pebs: how many physical eraseblocks are reserved for this volume
287 * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
288 * @usable_leb_size: logical eraseblock size without padding
289 * @used_ebs: how many logical eraseblocks in this volume contain data
290 * @last_eb_bytes: how many bytes are stored in the last logical eraseblock
291 * @used_bytes: how many bytes of data this volume contains
292 * @alignment: volume alignment
293 * @data_pad: how many bytes are not used at the end of physical eraseblocks to
294 *            satisfy the requested alignment
295 * @name_len: volume name length
296 * @name: volume name
297 *
298 * @upd_ebs: how many eraseblocks are expected to be updated
299 * @ch_lnum: LEB number which is being changing by the atomic LEB change
300 *           operation
301 * @upd_bytes: how many bytes are expected to be received for volume update or
302 *             atomic LEB change
303 * @upd_received: how many bytes were already received for volume update or
304 *                atomic LEB change
305 * @upd_buf: update buffer which is used to collect update data or data for
306 *           atomic LEB change
307 *
308 * @eba_tbl: EBA table of this volume (LEB->PEB mapping)
309 * @skip_check: %1 if CRC check of this static volume should be skipped.
310 *		Directly reflects the presence of the
311 *		%UBI_VTBL_SKIP_CRC_CHECK_FLG flag in the vtbl entry
312 * @checked: %1 if this static volume was checked
313 * @corrupted: %1 if the volume is corrupted (static volumes only)
314 * @upd_marker: %1 if the update marker is set for this volume
315 * @updating: %1 if the volume is being updated
316 * @changing_leb: %1 if the atomic LEB change ioctl command is in progress
317 * @direct_writes: %1 if direct writes are enabled for this volume
318 *
319 * @checkmap: bitmap to remember which PEB->LEB mappings got checked,
320 *            protected by UBI LEB lock tree.
321 *
322 * The @corrupted field indicates that the volume's contents is corrupted.
323 * Since UBI protects only static volumes, this field is not relevant to
324 * dynamic volumes - it is user's responsibility to assure their data
325 * integrity.
326 *
327 * The @upd_marker flag indicates that this volume is either being updated at
328 * the moment or is damaged because of an unclean reboot.
329 */
330struct ubi_volume {
331	struct device dev;
332	struct cdev cdev;
333	struct ubi_device *ubi;
334	int vol_id;
335	int ref_count;
336	int readers;
337	int writers;
338	int exclusive;
339	int metaonly;
340	bool is_dead;
341
342	int reserved_pebs;
343	int vol_type;
344	int usable_leb_size;
345	int used_ebs;
346	int last_eb_bytes;
347	long long used_bytes;
348	int alignment;
349	int data_pad;
350	int name_len;
351	char name[UBI_VOL_NAME_MAX + 1];
352
353	int upd_ebs;
354	int ch_lnum;
355	long long upd_bytes;
356	long long upd_received;
357	void *upd_buf;
358
359	struct ubi_eba_table *eba_tbl;
360	unsigned int skip_check:1;
361	unsigned int checked:1;
362	unsigned int corrupted:1;
363	unsigned int upd_marker:1;
364	unsigned int updating:1;
365	unsigned int changing_leb:1;
366	unsigned int direct_writes:1;
367
368#ifdef CONFIG_MTD_UBI_FASTMAP
369	unsigned long *checkmap;
370#endif
371};
372
373/**
374 * struct ubi_volume_desc - UBI volume descriptor returned when it is opened.
375 * @vol: reference to the corresponding volume description object
376 * @mode: open mode (%UBI_READONLY, %UBI_READWRITE, %UBI_EXCLUSIVE
377 * or %UBI_METAONLY)
378 */
379struct ubi_volume_desc {
380	struct ubi_volume *vol;
381	int mode;
382};
383
384/**
385 * struct ubi_debug_info - debugging information for an UBI device.
386 *
387 * @chk_gen: if UBI general extra checks are enabled
388 * @chk_io: if UBI I/O extra checks are enabled
389 * @chk_fastmap: if UBI fastmap extra checks are enabled
390 * @disable_bgt: disable the background task for testing purposes
391 * @emulate_bitflips: emulate bit-flips for testing purposes
392 * @emulate_io_failures: emulate write/erase failures for testing purposes
393 * @emulate_power_cut: emulate power cut for testing purposes
394 * @power_cut_counter: count down for writes left until emulated power cut
395 * @power_cut_min: minimum number of writes before emulating a power cut
396 * @power_cut_max: maximum number of writes until emulating a power cut
397 * @emulate_failures: emulate failures for testing purposes
398 * @dfs_dir_name: name of debugfs directory containing files of this UBI device
399 * @dfs_dir: direntry object of the UBI device debugfs directory
400 * @dfs_chk_gen: debugfs knob to enable UBI general extra checks
401 * @dfs_chk_io: debugfs knob to enable UBI I/O extra checks
402 * @dfs_chk_fastmap: debugfs knob to enable UBI fastmap extra checks
403 * @dfs_disable_bgt: debugfs knob to disable the background task
404 * @dfs_emulate_bitflips: debugfs knob to emulate bit-flips
405 * @dfs_emulate_io_failures: debugfs knob to emulate write/erase failures
406 * @dfs_emulate_power_cut: debugfs knob to emulate power cuts
407 * @dfs_power_cut_min: debugfs knob for minimum writes before power cut
408 * @dfs_power_cut_max: debugfs knob for maximum writes until power cut
409 * @dfs_emulate_failures: debugfs entry to control the fault injection type
410 */
411struct ubi_debug_info {
412	unsigned int chk_gen:1;
413	unsigned int chk_io:1;
414	unsigned int chk_fastmap:1;
415	unsigned int disable_bgt:1;
416	unsigned int emulate_bitflips:1;
417	unsigned int emulate_io_failures:1;
418	unsigned int emulate_power_cut:2;
419	unsigned int power_cut_counter;
420	unsigned int power_cut_min;
421	unsigned int power_cut_max;
422	unsigned int emulate_failures;
423	char dfs_dir_name[UBI_DFS_DIR_LEN + 1];
424	struct dentry *dfs_dir;
425	struct dentry *dfs_chk_gen;
426	struct dentry *dfs_chk_io;
427	struct dentry *dfs_chk_fastmap;
428	struct dentry *dfs_disable_bgt;
429	struct dentry *dfs_emulate_bitflips;
430	struct dentry *dfs_emulate_io_failures;
431	struct dentry *dfs_emulate_power_cut;
432	struct dentry *dfs_power_cut_min;
433	struct dentry *dfs_power_cut_max;
434	struct dentry *dfs_emulate_failures;
435};
436
437/**
438 * struct ubi_device - UBI device description structure
439 * @dev: UBI device object to use the Linux device model
440 * @cdev: character device object to create character device
441 * @ubi_num: UBI device number
442 * @ubi_name: UBI device name
443 * @vol_count: number of volumes in this UBI device
444 * @volumes: volumes of this UBI device
445 * @volumes_lock: protects @volumes, @rsvd_pebs, @avail_pebs, beb_rsvd_pebs,
446 *                @beb_rsvd_level, @bad_peb_count, @good_peb_count, @vol_count,
447 *                @vol->readers, @vol->writers, @vol->exclusive,
448 *                @vol->metaonly, @vol->ref_count, @vol->mapping and
449 *                @vol->eba_tbl.
450 * @ref_count: count of references on the UBI device
451 * @image_seq: image sequence number recorded on EC headers
452 *
453 * @rsvd_pebs: count of reserved physical eraseblocks
454 * @avail_pebs: count of available physical eraseblocks
455 * @beb_rsvd_pebs: how many physical eraseblocks are reserved for bad PEB
456 *                 handling
457 * @beb_rsvd_level: normal level of PEBs reserved for bad PEB handling
458 *
459 * @autoresize_vol_id: ID of the volume which has to be auto-resized at the end
460 *                     of UBI initialization
461 * @vtbl_slots: how many slots are available in the volume table
462 * @vtbl_size: size of the volume table in bytes
463 * @vtbl: in-RAM volume table copy
464 * @device_mutex: protects on-flash volume table and serializes volume
465 *                creation, deletion, update, re-size, re-name and set
466 *                property
467 *
468 * @max_ec: current highest erase counter value
469 * @mean_ec: current mean erase counter value
470 *
471 * @global_sqnum: global sequence number
472 * @ltree_lock: protects the lock tree and @global_sqnum
473 * @ltree: the lock tree
474 * @alc_mutex: serializes "atomic LEB change" operations
475 *
476 * @fm_disabled: non-zero if fastmap is disabled (default)
477 * @fm: in-memory data structure of the currently used fastmap
478 * @fm_pool: in-memory data structure of the fastmap pool
479 * @fm_wl_pool: in-memory data structure of the fastmap pool used by the WL
480 *		sub-system
481 * @fm_protect: serializes ubi_update_fastmap(), protects @fm_buf and makes sure
482 * that critical sections cannot be interrupted by ubi_update_fastmap()
483 * @fm_buf: vmalloc()'d buffer which holds the raw fastmap
484 * @fm_size: fastmap size in bytes
485 * @fm_eba_sem: allows ubi_update_fastmap() to block EBA table changes
486 * @fm_work: fastmap work queue
487 * @fm_work_scheduled: non-zero if fastmap work was scheduled
488 * @fast_attach: non-zero if UBI was attached by fastmap
489 * @fm_anchor: The next anchor PEB to use for fastmap
490 * @fm_do_produce_anchor: If true produce an anchor PEB in wl
491 * @fm_pool_rsv_cnt: Number of reserved PEBs for filling pool/wl_pool
492 *
493 * @used: RB-tree of used physical eraseblocks
494 * @erroneous: RB-tree of erroneous used physical eraseblocks
495 * @free: RB-tree of free physical eraseblocks
496 * @free_count: Contains the number of elements in @free
497 * @scrub: RB-tree of physical eraseblocks which need scrubbing
498 * @pq: protection queue (contain physical eraseblocks which are temporarily
499 *      protected from the wear-leveling worker)
500 * @pq_head: protection queue head
501 * @wl_lock: protects the @used, @free, @pq, @pq_head, @lookuptbl, @move_from,
502 *	     @move_to, @move_to_put @erase_pending, @wl_scheduled, @works,
503 *	     @erroneous, @erroneous_peb_count, @fm_work_scheduled, @fm_pool,
504 *	     and @fm_wl_pool fields
505 * @move_mutex: serializes eraseblock moves
506 * @work_sem: used to wait for all the scheduled works to finish and prevent
507 * new works from being submitted
508 * @wl_scheduled: non-zero if the wear-leveling was scheduled
509 * @lookuptbl: a table to quickly find a &struct ubi_wl_entry object for any
510 *             physical eraseblock
511 * @move_from: physical eraseblock from where the data is being moved
512 * @move_to: physical eraseblock where the data is being moved to
513 * @move_to_put: if the "to" PEB was put
514 * @works: list of pending works
515 * @works_count: count of pending works
516 * @bgt_thread: background thread description object
517 * @thread_enabled: if the background thread is enabled
518 * @bgt_name: background thread name
519 *
520 * @flash_size: underlying MTD device size (in bytes)
521 * @peb_count: count of physical eraseblocks on the MTD device
522 * @peb_size: physical eraseblock size
523 * @bad_peb_limit: top limit of expected bad physical eraseblocks
524 * @bad_peb_count: count of bad physical eraseblocks
525 * @good_peb_count: count of good physical eraseblocks
526 * @corr_peb_count: count of corrupted physical eraseblocks (preserved and not
527 *                  used by UBI)
528 * @erroneous_peb_count: count of erroneous physical eraseblocks in @erroneous
529 * @max_erroneous: maximum allowed amount of erroneous physical eraseblocks
530 * @min_io_size: minimal input/output unit size of the underlying MTD device
531 * @hdrs_min_io_size: minimal I/O unit size used for VID and EC headers
532 * @ro_mode: if the UBI device is in read-only mode
533 * @leb_size: logical eraseblock size
534 * @leb_start: starting offset of logical eraseblocks within physical
535 *             eraseblocks
536 * @ec_hdr_alsize: size of the EC header aligned to @hdrs_min_io_size
537 * @vid_hdr_alsize: size of the VID header aligned to @hdrs_min_io_size
538 * @vid_hdr_offset: starting offset of the volume identifier header (might be
539 *                  unaligned)
540 * @vid_hdr_aloffset: starting offset of the VID header aligned to
541 *                    @hdrs_min_io_size
542 * @vid_hdr_shift: contains @vid_hdr_offset - @vid_hdr_aloffset
543 * @bad_allowed: whether the MTD device admits bad physical eraseblocks or not
544 * @nor_flash: non-zero if working on top of NOR flash
545 * @max_write_size: maximum amount of bytes the underlying flash can write at a
546 *                  time (MTD write buffer size)
547 * @mtd: MTD device descriptor
548 *
549 * @peb_buf: a buffer of PEB size used for different purposes
550 * @buf_mutex: protects @peb_buf
551 * @ckvol_mutex: serializes static volume checking when opening
552 *
553 * @dbg: debugging information for this UBI device
554 */
555struct ubi_device {
556	struct cdev cdev;
557	struct device dev;
558	int ubi_num;
559	char ubi_name[sizeof(UBI_NAME_STR)+5];
560	int vol_count;
561	struct ubi_volume *volumes[UBI_MAX_VOLUMES+UBI_INT_VOL_COUNT];
562	spinlock_t volumes_lock;
563	int ref_count;
564	int image_seq;
565	bool is_dead;
566
567	int rsvd_pebs;
568	int avail_pebs;
569	int beb_rsvd_pebs;
570	int beb_rsvd_level;
571	int bad_peb_limit;
572
573	int autoresize_vol_id;
574	int vtbl_slots;
575	int vtbl_size;
576	struct ubi_vtbl_record *vtbl;
577	struct mutex device_mutex;
578
579	int max_ec;
580	/* Note, mean_ec is not updated run-time - should be fixed */
581	int mean_ec;
582
583	/* EBA sub-system's stuff */
584	unsigned long long global_sqnum;
585	spinlock_t ltree_lock;
586	struct rb_root ltree;
587	struct mutex alc_mutex;
588
589	/* Fastmap stuff */
590	int fm_disabled;
591	struct ubi_fastmap_layout *fm;
592	struct ubi_fm_pool fm_pool;
593	struct ubi_fm_pool fm_wl_pool;
594	struct rw_semaphore fm_eba_sem;
595	struct rw_semaphore fm_protect;
596	void *fm_buf;
597	size_t fm_size;
598	struct work_struct fm_work;
599	int fm_work_scheduled;
600	int fast_attach;
601	struct ubi_wl_entry *fm_anchor;
602	int fm_do_produce_anchor;
603	int fm_pool_rsv_cnt;
604
605	/* Wear-leveling sub-system's stuff */
606	struct rb_root used;
607	struct rb_root erroneous;
608	struct rb_root free;
609	int free_count;
610	struct rb_root scrub;
611	struct list_head pq[UBI_PROT_QUEUE_LEN];
612	int pq_head;
613	spinlock_t wl_lock;
614	struct mutex move_mutex;
615	struct rw_semaphore work_sem;
616	int wl_scheduled;
617	struct ubi_wl_entry **lookuptbl;
618	struct ubi_wl_entry *move_from;
619	struct ubi_wl_entry *move_to;
620	int move_to_put;
621	struct list_head works;
622	int works_count;
623	struct task_struct *bgt_thread;
624	int thread_enabled;
625	char bgt_name[sizeof(UBI_BGT_NAME_PATTERN)+2];
626
627	/* I/O sub-system's stuff */
628	long long flash_size;
629	int peb_count;
630	int peb_size;
631	int bad_peb_count;
632	int good_peb_count;
633	int corr_peb_count;
634	int erroneous_peb_count;
635	int max_erroneous;
636	int min_io_size;
637	int hdrs_min_io_size;
638	int ro_mode;
639	int leb_size;
640	int leb_start;
641	int ec_hdr_alsize;
642	int vid_hdr_alsize;
643	int vid_hdr_offset;
644	int vid_hdr_aloffset;
645	int vid_hdr_shift;
646	unsigned int bad_allowed:1;
647	unsigned int nor_flash:1;
648	int max_write_size;
649	struct mtd_info *mtd;
650
651	void *peb_buf;
652	struct mutex buf_mutex;
653	struct mutex ckvol_mutex;
654
655	struct ubi_debug_info dbg;
656};
657
658/**
659 * struct ubi_ainf_peb - attach information about a physical eraseblock.
660 * @ec: erase counter (%UBI_UNKNOWN if it is unknown)
661 * @pnum: physical eraseblock number
662 * @vol_id: ID of the volume this LEB belongs to
663 * @lnum: logical eraseblock number
664 * @scrub: if this physical eraseblock needs scrubbing
665 * @copy_flag: this LEB is a copy (@copy_flag is set in VID header of this LEB)
666 * @sqnum: sequence number
667 * @u: unions RB-tree or @list links
668 * @u.rb: link in the per-volume RB-tree of &struct ubi_ainf_peb objects
669 * @u.list: link in one of the eraseblock lists
670 *
671 * One object of this type is allocated for each physical eraseblock when
672 * attaching an MTD device. Note, if this PEB does not belong to any LEB /
673 * volume, the @vol_id and @lnum fields are initialized to %UBI_UNKNOWN.
674 */
675struct ubi_ainf_peb {
676	int ec;
677	int pnum;
678	int vol_id;
679	int lnum;
680	unsigned int scrub:1;
681	unsigned int copy_flag:1;
682	unsigned long long sqnum;
683	union {
684		struct rb_node rb;
685		struct list_head list;
686	} u;
687};
688
689/**
690 * struct ubi_ainf_volume - attaching information about a volume.
691 * @vol_id: volume ID
692 * @highest_lnum: highest logical eraseblock number in this volume
693 * @leb_count: number of logical eraseblocks in this volume
694 * @vol_type: volume type
695 * @used_ebs: number of used logical eraseblocks in this volume (only for
696 *            static volumes)
697 * @last_data_size: amount of data in the last logical eraseblock of this
698 *                  volume (always equivalent to the usable logical eraseblock
699 *                  size in case of dynamic volumes)
700 * @data_pad: how many bytes at the end of logical eraseblocks of this volume
701 *            are not used (due to volume alignment)
702 * @compat: compatibility flags of this volume
703 * @rb: link in the volume RB-tree
704 * @root: root of the RB-tree containing all the eraseblock belonging to this
705 *        volume (&struct ubi_ainf_peb objects)
706 *
707 * One object of this type is allocated for each volume when attaching an MTD
708 * device.
709 */
710struct ubi_ainf_volume {
711	int vol_id;
712	int highest_lnum;
713	int leb_count;
714	int vol_type;
715	int used_ebs;
716	int last_data_size;
717	int data_pad;
718	int compat;
719	struct rb_node rb;
720	struct rb_root root;
721};
722
723/**
724 * struct ubi_attach_info - MTD device attaching information.
725 * @volumes: root of the volume RB-tree
726 * @corr: list of corrupted physical eraseblocks
727 * @free: list of free physical eraseblocks
728 * @erase: list of physical eraseblocks which have to be erased
729 * @alien: list of physical eraseblocks which should not be used by UBI (e.g.,
730 *         those belonging to "preserve"-compatible internal volumes)
731 * @fastmap: list of physical eraseblocks which relate to fastmap (e.g.,
732 *           eraseblocks of the current and not yet erased old fastmap blocks)
733 * @corr_peb_count: count of PEBs in the @corr list
734 * @empty_peb_count: count of PEBs which are presumably empty (contain only
735 *                   0xFF bytes)
736 * @alien_peb_count: count of PEBs in the @alien list
737 * @bad_peb_count: count of bad physical eraseblocks
738 * @maybe_bad_peb_count: count of bad physical eraseblocks which are not marked
739 *                       as bad yet, but which look like bad
740 * @vols_found: number of volumes found
741 * @highest_vol_id: highest volume ID
742 * @is_empty: flag indicating whether the MTD device is empty or not
743 * @force_full_scan: flag indicating whether we need to do a full scan and drop
744		     all existing Fastmap data structures
745 * @min_ec: lowest erase counter value
746 * @max_ec: highest erase counter value
747 * @max_sqnum: highest sequence number value
748 * @mean_ec: mean erase counter value
749 * @ec_sum: a temporary variable used when calculating @mean_ec
750 * @ec_count: a temporary variable used when calculating @mean_ec
751 * @aeb_slab_cache: slab cache for &struct ubi_ainf_peb objects
752 * @ech: temporary EC header. Only available during scan
753 * @vidh: temporary VID buffer. Only available during scan
754 *
755 * This data structure contains the result of attaching an MTD device and may
756 * be used by other UBI sub-systems to build final UBI data structures, further
757 * error-recovery and so on.
758 */
759struct ubi_attach_info {
760	struct rb_root volumes;
761	struct list_head corr;
762	struct list_head free;
763	struct list_head erase;
764	struct list_head alien;
765	struct list_head fastmap;
766	int corr_peb_count;
767	int empty_peb_count;
768	int alien_peb_count;
769	int bad_peb_count;
770	int maybe_bad_peb_count;
771	int vols_found;
772	int highest_vol_id;
773	int is_empty;
774	int force_full_scan;
775	int min_ec;
776	int max_ec;
777	unsigned long long max_sqnum;
778	int mean_ec;
779	uint64_t ec_sum;
780	int ec_count;
781	struct kmem_cache *aeb_slab_cache;
782	struct ubi_ec_hdr *ech;
783	struct ubi_vid_io_buf *vidb;
784};
785
786/**
787 * struct ubi_work - UBI work description data structure.
788 * @list: a link in the list of pending works
789 * @func: worker function
790 * @e: physical eraseblock to erase
791 * @vol_id: the volume ID on which this erasure is being performed
792 * @lnum: the logical eraseblock number
793 * @torture: if the physical eraseblock has to be tortured
794 *
795 * The @func pointer points to the worker function. If the @shutdown argument is
796 * not zero, the worker has to free the resources and exit immediately as the
797 * WL sub-system is shutting down.
798 * The worker has to return zero in case of success and a negative error code in
799 * case of failure.
800 */
801struct ubi_work {
802	struct list_head list;
803	int (*func)(struct ubi_device *ubi, struct ubi_work *wrk, int shutdown);
804	/* The below fields are only relevant to erasure works */
805	struct ubi_wl_entry *e;
806	int vol_id;
807	int lnum;
808	int torture;
809};
810
811#include "debug.h"
812
813extern struct kmem_cache *ubi_wl_entry_slab;
814extern const struct file_operations ubi_ctrl_cdev_operations;
815extern const struct file_operations ubi_cdev_operations;
816extern const struct file_operations ubi_vol_cdev_operations;
817extern struct class ubi_class;
818extern struct mutex ubi_devices_mutex;
819extern struct blocking_notifier_head ubi_notifiers;
820
821/* attach.c */
822struct ubi_ainf_peb *ubi_alloc_aeb(struct ubi_attach_info *ai, int pnum,
823				   int ec);
824void ubi_free_aeb(struct ubi_attach_info *ai, struct ubi_ainf_peb *aeb);
825int ubi_add_to_av(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum,
826		  int ec, const struct ubi_vid_hdr *vid_hdr, int bitflips);
827struct ubi_ainf_volume *ubi_add_av(struct ubi_attach_info *ai, int vol_id);
828struct ubi_ainf_volume *ubi_find_av(const struct ubi_attach_info *ai,
829				    int vol_id);
830void ubi_remove_av(struct ubi_attach_info *ai, struct ubi_ainf_volume *av);
831struct ubi_ainf_peb *ubi_early_get_peb(struct ubi_device *ubi,
832				       struct ubi_attach_info *ai);
833int ubi_attach(struct ubi_device *ubi, int force_scan);
834void ubi_destroy_ai(struct ubi_attach_info *ai);
835
836/* vtbl.c */
837int ubi_change_vtbl_record(struct ubi_device *ubi, int idx,
838			   struct ubi_vtbl_record *vtbl_rec);
839int ubi_vtbl_rename_volumes(struct ubi_device *ubi,
840			    struct list_head *rename_list);
841int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_attach_info *ai);
842
843/* vmt.c */
844int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req);
845int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl);
846int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs);
847int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list);
848int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol);
849void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol);
850
851/* upd.c */
852int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol,
853		     long long bytes);
854int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol,
855			 const void __user *buf, int count);
856int ubi_start_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
857			 const struct ubi_leb_change_req *req);
858int ubi_more_leb_change_data(struct ubi_device *ubi, struct ubi_volume *vol,
859			     const void __user *buf, int count);
860
861/* misc.c */
862int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf,
863		      int length);
864int ubi_check_volume(struct ubi_device *ubi, int vol_id);
865void ubi_update_reserved(struct ubi_device *ubi);
866void ubi_calculate_reserved(struct ubi_device *ubi);
867int ubi_check_pattern(const void *buf, uint8_t patt, int size);
868
869static inline bool ubi_leb_valid(struct ubi_volume *vol, int lnum)
870{
871	return lnum >= 0 && lnum < vol->reserved_pebs;
872}
873
874/* eba.c */
875struct ubi_eba_table *ubi_eba_create_table(struct ubi_volume *vol,
876					   int nentries);
877void ubi_eba_destroy_table(struct ubi_eba_table *tbl);
878void ubi_eba_copy_table(struct ubi_volume *vol, struct ubi_eba_table *dst,
879			int nentries);
880void ubi_eba_replace_table(struct ubi_volume *vol, struct ubi_eba_table *tbl);
881void ubi_eba_get_ldesc(struct ubi_volume *vol, int lnum,
882		       struct ubi_eba_leb_desc *ldesc);
883bool ubi_eba_is_mapped(struct ubi_volume *vol, int lnum);
884int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol,
885		      int lnum);
886int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
887		     void *buf, int offset, int len, int check);
888int ubi_eba_read_leb_sg(struct ubi_device *ubi, struct ubi_volume *vol,
889			struct ubi_sgl *sgl, int lnum, int offset, int len,
890			int check);
891int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
892		      const void *buf, int offset, int len);
893int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol,
894			 int lnum, const void *buf, int len, int used_ebs);
895int ubi_eba_atomic_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
896			      int lnum, const void *buf, int len);
897int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
898		     struct ubi_vid_io_buf *vidb);
899int ubi_eba_init(struct ubi_device *ubi, struct ubi_attach_info *ai);
900unsigned long long ubi_next_sqnum(struct ubi_device *ubi);
901int self_check_eba(struct ubi_device *ubi, struct ubi_attach_info *ai_fastmap,
902		   struct ubi_attach_info *ai_scan);
903
904/* wl.c */
905int ubi_sync_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, int torture);
906int ubi_wl_get_peb(struct ubi_device *ubi);
907int ubi_wl_put_peb(struct ubi_device *ubi, int vol_id, int lnum,
908		   int pnum, int torture);
909int ubi_wl_flush(struct ubi_device *ubi, int vol_id, int lnum);
910int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum);
911int ubi_wl_init(struct ubi_device *ubi, struct ubi_attach_info *ai);
912void ubi_wl_close(struct ubi_device *ubi);
913int ubi_thread(void *u);
914struct ubi_wl_entry *ubi_wl_get_fm_peb(struct ubi_device *ubi, int anchor);
915int ubi_wl_put_fm_peb(struct ubi_device *ubi, struct ubi_wl_entry *used_e,
916		      int lnum, int torture);
917int ubi_is_erase_work(struct ubi_work *wrk);
918void ubi_refill_pools_and_lock(struct ubi_device *ubi);
919int ubi_ensure_anchor_pebs(struct ubi_device *ubi);
920int ubi_bitflip_check(struct ubi_device *ubi, int pnum, int force_scrub);
921
922/* io.c */
923int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset,
924		int len);
925int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
926		 int len);
927int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture);
928int ubi_io_is_bad(const struct ubi_device *ubi, int pnum);
929int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum);
930int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum,
931		       struct ubi_ec_hdr *ec_hdr, int verbose);
932int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum,
933			struct ubi_ec_hdr *ec_hdr);
934int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum,
935			struct ubi_vid_io_buf *vidb, int verbose);
936int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum,
937			 struct ubi_vid_io_buf *vidb);
938
939/* build.c */
940int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
941		       int vid_hdr_offset, int max_beb_per1024,
942		       bool disable_fm, bool need_resv_pool);
943int ubi_detach_mtd_dev(int ubi_num, int anyway);
944struct ubi_device *ubi_get_device(int ubi_num);
945void ubi_put_device(struct ubi_device *ubi);
946struct ubi_device *ubi_get_by_major(int major);
947int ubi_major2num(int major);
948int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol,
949		      int ntype);
950int ubi_notify_all(struct ubi_device *ubi, int ntype,
951		   struct notifier_block *nb);
952int ubi_enumerate_volumes(struct notifier_block *nb);
953void ubi_free_all_volumes(struct ubi_device *ubi);
954void ubi_free_internal_volumes(struct ubi_device *ubi);
955
956/* kapi.c */
957void ubi_do_get_device_info(struct ubi_device *ubi, struct ubi_device_info *di);
958void ubi_do_get_volume_info(struct ubi_device *ubi, struct ubi_volume *vol,
959			    struct ubi_volume_info *vi);
960int ubi_get_num_by_path(const char *pathname, int *ubi_num, int *vol_id);
961/* scan.c */
962int ubi_compare_lebs(struct ubi_device *ubi, const struct ubi_ainf_peb *aeb,
963		      int pnum, const struct ubi_vid_hdr *vid_hdr);
964
965/* fastmap.c */
966#ifdef CONFIG_MTD_UBI_FASTMAP
967size_t ubi_calc_fm_size(struct ubi_device *ubi);
968int ubi_update_fastmap(struct ubi_device *ubi);
969int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
970		     struct ubi_attach_info *scan_ai);
971int ubi_fastmap_init_checkmap(struct ubi_volume *vol, int leb_count);
972void ubi_fastmap_destroy_checkmap(struct ubi_volume *vol);
973#else
974static inline int ubi_update_fastmap(struct ubi_device *ubi) { return 0; }
975static inline int ubi_fastmap_init_checkmap(struct ubi_volume *vol, int leb_count) { return 0; }
976static inline void ubi_fastmap_destroy_checkmap(struct ubi_volume *vol) {}
977#endif
978
979/* block.c */
980#ifdef CONFIG_MTD_UBI_BLOCK
981int ubiblock_init(void);
982void ubiblock_exit(void);
983int ubiblock_create(struct ubi_volume_info *vi);
984int ubiblock_remove(struct ubi_volume_info *vi);
985#else
986static inline int ubiblock_init(void) { return 0; }
987static inline void ubiblock_exit(void) {}
988static inline int ubiblock_create(struct ubi_volume_info *vi)
989{
990	return -ENOSYS;
991}
992static inline int ubiblock_remove(struct ubi_volume_info *vi)
993{
994	return -ENOSYS;
995}
996#endif
997
998/*
999 * ubi_for_each_free_peb - walk the UBI free RB tree.
1000 * @ubi: UBI device description object
1001 * @e: a pointer to a ubi_wl_entry to use as cursor
1002 * @pos: a pointer to RB-tree entry type to use as a loop counter
1003 */
1004#define ubi_for_each_free_peb(ubi, e, tmp_rb)	\
1005	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->free, u.rb)
1006
1007/*
1008 * ubi_for_each_used_peb - walk the UBI used RB tree.
1009 * @ubi: UBI device description object
1010 * @e: a pointer to a ubi_wl_entry to use as cursor
1011 * @pos: a pointer to RB-tree entry type to use as a loop counter
1012 */
1013#define ubi_for_each_used_peb(ubi, e, tmp_rb)	\
1014	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->used, u.rb)
1015
1016/*
1017 * ubi_for_each_scub_peb - walk the UBI scub RB tree.
1018 * @ubi: UBI device description object
1019 * @e: a pointer to a ubi_wl_entry to use as cursor
1020 * @pos: a pointer to RB-tree entry type to use as a loop counter
1021 */
1022#define ubi_for_each_scrub_peb(ubi, e, tmp_rb)	\
1023	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->scrub, u.rb)
1024
1025/*
1026 * ubi_for_each_protected_peb - walk the UBI protection queue.
1027 * @ubi: UBI device description object
1028 * @i: a integer used as counter
1029 * @e: a pointer to a ubi_wl_entry to use as cursor
1030 */
1031#define ubi_for_each_protected_peb(ubi, i, e)	\
1032	for ((i) = 0; (i) < UBI_PROT_QUEUE_LEN; (i)++)	\
1033		list_for_each_entry((e), &(ubi->pq[(i)]), u.list)
1034
1035/*
1036 * ubi_rb_for_each_entry - walk an RB-tree.
1037 * @rb: a pointer to type 'struct rb_node' to use as a loop counter
1038 * @pos: a pointer to RB-tree entry type to use as a loop counter
1039 * @root: RB-tree's root
1040 * @member: the name of the 'struct rb_node' within the RB-tree entry
1041 */
1042#define ubi_rb_for_each_entry(rb, pos, root, member)                         \
1043	for (rb = rb_first(root),                                            \
1044	     pos = (rb ? container_of(rb, typeof(*pos), member) : NULL);     \
1045	     rb;                                                             \
1046	     rb = rb_next(rb),                                               \
1047	     pos = (rb ? container_of(rb, typeof(*pos), member) : NULL))
1048
1049/*
1050 * ubi_move_aeb_to_list - move a PEB from the volume tree to a list.
1051 *
1052 * @av: volume attaching information
1053 * @aeb: attaching eraseblock information
1054 * @list: the list to move to
1055 */
1056static inline void ubi_move_aeb_to_list(struct ubi_ainf_volume *av,
1057					 struct ubi_ainf_peb *aeb,
1058					 struct list_head *list)
1059{
1060		rb_erase(&aeb->u.rb, &av->root);
1061		list_add_tail(&aeb->u.list, list);
1062}
1063
1064/**
1065 * ubi_init_vid_buf - Initialize a VID buffer
1066 * @ubi: the UBI device
1067 * @vidb: the VID buffer to initialize
1068 * @buf: the underlying buffer
1069 */
1070static inline void ubi_init_vid_buf(const struct ubi_device *ubi,
1071				    struct ubi_vid_io_buf *vidb,
1072				    void *buf)
1073{
1074	if (buf)
1075		memset(buf, 0, ubi->vid_hdr_alsize);
1076
1077	vidb->buffer = buf;
1078	vidb->hdr = buf + ubi->vid_hdr_shift;
1079}
1080
1081/**
1082 * ubi_init_vid_buf - Allocate a VID buffer
1083 * @ubi: the UBI device
1084 * @gfp_flags: GFP flags to use for the allocation
1085 */
1086static inline struct ubi_vid_io_buf *
1087ubi_alloc_vid_buf(const struct ubi_device *ubi, gfp_t gfp_flags)
1088{
1089	struct ubi_vid_io_buf *vidb;
1090	void *buf;
1091
1092	vidb = kzalloc(sizeof(*vidb), gfp_flags);
1093	if (!vidb)
1094		return NULL;
1095
1096	buf = kmalloc(ubi->vid_hdr_alsize, gfp_flags);
1097	if (!buf) {
1098		kfree(vidb);
1099		return NULL;
1100	}
1101
1102	ubi_init_vid_buf(ubi, vidb, buf);
1103
1104	return vidb;
1105}
1106
1107/**
1108 * ubi_free_vid_buf - Free a VID buffer
1109 * @vidb: the VID buffer to free
1110 */
1111static inline void ubi_free_vid_buf(struct ubi_vid_io_buf *vidb)
1112{
1113	if (!vidb)
1114		return;
1115
1116	kfree(vidb->buffer);
1117	kfree(vidb);
1118}
1119
1120/**
1121 * ubi_get_vid_hdr - Get the VID header attached to a VID buffer
1122 * @vidb: VID buffer
1123 */
1124static inline struct ubi_vid_hdr *ubi_get_vid_hdr(struct ubi_vid_io_buf *vidb)
1125{
1126	return vidb->hdr;
1127}
1128
1129/**
1130 * ubi_ro_mode - switch to read-only mode.
1131 * @ubi: UBI device description object
1132 */
1133static inline void ubi_ro_mode(struct ubi_device *ubi)
1134{
1135	if (!ubi->ro_mode) {
1136		ubi->ro_mode = 1;
1137		ubi_warn(ubi, "switch to read-only mode");
1138		dump_stack();
1139	}
1140}
1141
1142/*
1143 * This function is equivalent to 'ubi_io_read()', but @offset is relative to
1144 * the beginning of the logical eraseblock, not to the beginning of the
1145 * physical eraseblock.
1146 */
1147static inline int ubi_io_read_data(const struct ubi_device *ubi, void *buf,
1148				   int pnum, int offset, int len)
1149{
1150	ubi_assert(offset >= 0);
1151	return ubi_io_read(ubi, buf, pnum, offset + ubi->leb_start, len);
1152}
1153
1154/*
1155 * This function is equivalent to 'ubi_io_write()', but @offset is relative to
1156 * the beginning of the logical eraseblock, not to the beginning of the
1157 * physical eraseblock.
1158 */
1159static inline int ubi_io_write_data(struct ubi_device *ubi, const void *buf,
1160				    int pnum, int offset, int len)
1161{
1162	ubi_assert(offset >= 0);
1163
1164	if (ubi_dbg_power_cut(ubi, MASK_POWER_CUT_DATA)) {
1165		ubi_warn(ubi, "XXXXX emulating a power cut when writing data XXXXX");
1166		ubi_ro_mode(ubi);
1167		return -EROFS;
1168	}
1169	return ubi_io_write(ubi, buf, pnum, offset + ubi->leb_start, len);
1170}
1171
1172/**
1173 * vol_id2idx - get table index by volume ID.
1174 * @ubi: UBI device description object
1175 * @vol_id: volume ID
1176 */
1177static inline int vol_id2idx(const struct ubi_device *ubi, int vol_id)
1178{
1179	if (vol_id >= UBI_INTERNAL_VOL_START)
1180		return vol_id - UBI_INTERNAL_VOL_START + ubi->vtbl_slots;
1181	else
1182		return vol_id;
1183}
1184
1185/**
1186 * idx2vol_id - get volume ID by table index.
1187 * @ubi: UBI device description object
1188 * @idx: table index
1189 */
1190static inline int idx2vol_id(const struct ubi_device *ubi, int idx)
1191{
1192	if (idx >= ubi->vtbl_slots)
1193		return idx - ubi->vtbl_slots + UBI_INTERNAL_VOL_START;
1194	else
1195		return idx;
1196}
1197
1198/**
1199 * ubi_is_fm_vol - check whether a volume ID is a Fastmap volume.
1200 * @vol_id: volume ID
1201 */
1202static inline bool ubi_is_fm_vol(int vol_id)
1203{
1204	switch (vol_id) {
1205		case UBI_FM_SB_VOLUME_ID:
1206		case UBI_FM_DATA_VOLUME_ID:
1207		return true;
1208	}
1209
1210	return false;
1211}
1212
1213/**
1214 * ubi_find_fm_block - check whether a PEB is part of the current Fastmap.
1215 * @ubi: UBI device description object
1216 * @pnum: physical eraseblock to look for
1217 *
1218 * This function returns a wear leveling object if @pnum relates to the current
1219 * fastmap, @NULL otherwise.
1220 */
1221static inline struct ubi_wl_entry *ubi_find_fm_block(const struct ubi_device *ubi,
1222						     int pnum)
1223{
1224	int i;
1225
1226	if (ubi->fm) {
1227		for (i = 0; i < ubi->fm->used_blocks; i++) {
1228			if (ubi->fm->e[i]->pnum == pnum)
1229				return ubi->fm->e[i];
1230		}
1231	}
1232
1233	return NULL;
1234}
1235
1236#endif /* !__UBI_UBI_H__ */
1237