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/types.h>
26#include <linux/list.h>
27#include <linux/rbtree.h>
28#include <linux/sched.h>
29#include <linux/wait.h>
30#include <linux/mutex.h>
31#include <linux/rwsem.h>
32#include <linux/spinlock.h>
33#include <linux/fs.h>
34#include <linux/cdev.h>
35#include <linux/device.h>
36#include <linux/slab.h>
37#include <linux/string.h>
38#include <linux/vmalloc.h>
39#include <linux/notifier.h>
40#include <linux/mtd/mtd.h>
41#include <linux/mtd/ubi.h>
42#include <asm/pgtable.h>
43
44#include "ubi-media.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(ubi, fmt, ...) pr_notice(UBI_NAME_STR "%d: " fmt "\n", \
54					 ubi->ubi_num, ##__VA_ARGS__)
55/* UBI warning messages */
56#define ubi_warn(ubi, fmt, ...) pr_warn(UBI_NAME_STR "%d warning: %s: " fmt "\n", \
57					ubi->ubi_num, __func__, ##__VA_ARGS__)
58/* UBI error messages */
59#define ubi_err(ubi, fmt, ...) pr_err(UBI_NAME_STR "%d error: %s: " fmt "\n", \
60				      ubi->ubi_num, __func__, ##__VA_ARGS__)
61
62/* Background thread name pattern */
63#define UBI_BGT_NAME_PATTERN "ubi_bgt%dd"
64
65/*
66 * This marker in the EBA table means that the LEB is um-mapped.
67 * NOTE! It has to have the same value as %UBI_ALL.
68 */
69#define UBI_LEB_UNMAPPED -1
70
71/*
72 * In case of errors, UBI tries to repeat the operation several times before
73 * returning error. The below constant defines how many times UBI re-tries.
74 */
75#define UBI_IO_RETRIES 3
76
77/*
78 * Length of the protection queue. The length is effectively equivalent to the
79 * number of (global) erase cycles PEBs are protected from the wear-leveling
80 * worker.
81 */
82#define UBI_PROT_QUEUE_LEN 10
83
84/* The volume ID/LEB number/erase counter is unknown */
85#define UBI_UNKNOWN -1
86
87/*
88 * The UBI debugfs directory name pattern and maximum name length (3 for "ubi"
89 * + 2 for the number plus 1 for the trailing zero byte.
90 */
91#define UBI_DFS_DIR_NAME "ubi%d"
92#define UBI_DFS_DIR_LEN  (3 + 2 + 1)
93
94/*
95 * Error codes returned by the I/O sub-system.
96 *
97 * UBI_IO_FF: the read region of flash contains only 0xFFs
98 * UBI_IO_FF_BITFLIPS: the same as %UBI_IO_FF, but also also there was a data
99 *                     integrity error reported by the MTD driver
100 *                     (uncorrectable ECC error in case of NAND)
101 * UBI_IO_BAD_HDR: the EC or VID header is corrupted (bad magic or CRC)
102 * UBI_IO_BAD_HDR_EBADMSG: the same as %UBI_IO_BAD_HDR, but also there was a
103 *                         data integrity error reported by the MTD driver
104 *                         (uncorrectable ECC error in case of NAND)
105 * UBI_IO_BITFLIPS: bit-flips were detected and corrected
106 *
107 * Note, it is probably better to have bit-flip and ebadmsg as flags which can
108 * be or'ed with other error code. But this is a big change because there are
109 * may callers, so it does not worth the risk of introducing a bug
110 */
111enum {
112	UBI_IO_FF = 1,
113	UBI_IO_FF_BITFLIPS,
114	UBI_IO_BAD_HDR,
115	UBI_IO_BAD_HDR_EBADMSG,
116	UBI_IO_BITFLIPS,
117};
118
119/*
120 * Return codes of the 'ubi_eba_copy_leb()' function.
121 *
122 * MOVE_CANCEL_RACE: canceled because the volume is being deleted, the source
123 *                   PEB was put meanwhile, or there is I/O on the source PEB
124 * MOVE_SOURCE_RD_ERR: canceled because there was a read error from the source
125 *                     PEB
126 * MOVE_TARGET_RD_ERR: canceled because there was a read error from the target
127 *                     PEB
128 * MOVE_TARGET_WR_ERR: canceled because there was a write error to the target
129 *                     PEB
130 * MOVE_TARGET_BITFLIPS: canceled because a bit-flip was detected in the
131 *                       target PEB
132 * MOVE_RETRY: retry scrubbing the PEB
133 */
134enum {
135	MOVE_CANCEL_RACE = 1,
136	MOVE_SOURCE_RD_ERR,
137	MOVE_TARGET_RD_ERR,
138	MOVE_TARGET_WR_ERR,
139	MOVE_TARGET_BITFLIPS,
140	MOVE_RETRY,
141};
142
143/*
144 * Return codes of the fastmap sub-system
145 *
146 * UBI_NO_FASTMAP: No fastmap super block was found
147 * UBI_BAD_FASTMAP: A fastmap was found but it's unusable
148 */
149enum {
150	UBI_NO_FASTMAP = 1,
151	UBI_BAD_FASTMAP,
152};
153
154/*
155 * Flags for emulate_power_cut in ubi_debug_info
156 *
157 * POWER_CUT_EC_WRITE: Emulate a power cut when writing an EC header
158 * POWER_CUT_VID_WRITE: Emulate a power cut when writing a VID header
159 */
160enum {
161	POWER_CUT_EC_WRITE = 0x01,
162	POWER_CUT_VID_WRITE = 0x02,
163};
164
165/**
166 * struct ubi_wl_entry - wear-leveling entry.
167 * @u.rb: link in the corresponding (free/used) RB-tree
168 * @u.list: link in the protection queue
169 * @ec: erase counter
170 * @pnum: physical eraseblock number
171 *
172 * This data structure is used in the WL sub-system. Each physical eraseblock
173 * has a corresponding &struct wl_entry object which may be kept in different
174 * RB-trees. See WL sub-system for details.
175 */
176struct ubi_wl_entry {
177	union {
178		struct rb_node rb;
179		struct list_head list;
180	} u;
181	int ec;
182	int pnum;
183};
184
185/**
186 * struct ubi_ltree_entry - an entry in the lock tree.
187 * @rb: links RB-tree nodes
188 * @vol_id: volume ID of the locked logical eraseblock
189 * @lnum: locked logical eraseblock number
190 * @users: how many tasks are using this logical eraseblock or wait for it
191 * @mutex: read/write mutex to implement read/write access serialization to
192 *         the (@vol_id, @lnum) logical eraseblock
193 *
194 * This data structure is used in the EBA sub-system to implement per-LEB
195 * locking. When a logical eraseblock is being locked - corresponding
196 * &struct ubi_ltree_entry object is inserted to the lock tree (@ubi->ltree).
197 * See EBA sub-system for details.
198 */
199struct ubi_ltree_entry {
200	struct rb_node rb;
201	int vol_id;
202	int lnum;
203	int users;
204	struct rw_semaphore mutex;
205};
206
207/**
208 * struct ubi_rename_entry - volume re-name description data structure.
209 * @new_name_len: new volume name length
210 * @new_name: new volume name
211 * @remove: if not zero, this volume should be removed, not re-named
212 * @desc: descriptor of the volume
213 * @list: links re-name entries into a list
214 *
215 * This data structure is utilized in the multiple volume re-name code. Namely,
216 * UBI first creates a list of &struct ubi_rename_entry objects from the
217 * &struct ubi_rnvol_req request object, and then utilizes this list to do all
218 * the job.
219 */
220struct ubi_rename_entry {
221	int new_name_len;
222	char new_name[UBI_VOL_NAME_MAX + 1];
223	int remove;
224	struct ubi_volume_desc *desc;
225	struct list_head list;
226};
227
228struct ubi_volume_desc;
229
230/**
231 * struct ubi_fastmap_layout - in-memory fastmap data structure.
232 * @e: PEBs used by the current fastmap
233 * @to_be_tortured: if non-zero tortured this PEB
234 * @used_blocks: number of used PEBs
235 * @max_pool_size: maximal size of the user pool
236 * @max_wl_pool_size: maximal size of the pool used by the WL sub-system
237 */
238struct ubi_fastmap_layout {
239	struct ubi_wl_entry *e[UBI_FM_MAX_BLOCKS];
240	int to_be_tortured[UBI_FM_MAX_BLOCKS];
241	int used_blocks;
242	int max_pool_size;
243	int max_wl_pool_size;
244};
245
246/**
247 * struct ubi_fm_pool - in-memory fastmap pool
248 * @pebs: PEBs in this pool
249 * @used: number of used PEBs
250 * @size: total number of PEBs in this pool
251 * @max_size: maximal size of the pool
252 *
253 * A pool gets filled with up to max_size.
254 * If all PEBs within the pool are used a new fastmap will be written
255 * to the flash and the pool gets refilled with empty PEBs.
256 *
257 */
258struct ubi_fm_pool {
259	int pebs[UBI_FM_MAX_POOL_SIZE];
260	int used;
261	int size;
262	int max_size;
263};
264
265/**
266 * struct ubi_volume - UBI volume description data structure.
267 * @dev: device object to make use of the the Linux device model
268 * @cdev: character device object to create character device
269 * @ubi: reference to the UBI device description object
270 * @vol_id: volume ID
271 * @ref_count: volume reference count
272 * @readers: number of users holding this volume in read-only mode
273 * @writers: number of users holding this volume in read-write mode
274 * @exclusive: whether somebody holds this volume in exclusive mode
275 * @metaonly: whether somebody is altering only meta data of this volume
276 *
277 * @reserved_pebs: how many physical eraseblocks are reserved for this volume
278 * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
279 * @usable_leb_size: logical eraseblock size without padding
280 * @used_ebs: how many logical eraseblocks in this volume contain data
281 * @last_eb_bytes: how many bytes are stored in the last logical eraseblock
282 * @used_bytes: how many bytes of data this volume contains
283 * @alignment: volume alignment
284 * @data_pad: how many bytes are not used at the end of physical eraseblocks to
285 *            satisfy the requested alignment
286 * @name_len: volume name length
287 * @name: volume name
288 *
289 * @upd_ebs: how many eraseblocks are expected to be updated
290 * @ch_lnum: LEB number which is being changing by the atomic LEB change
291 *           operation
292 * @upd_bytes: how many bytes are expected to be received for volume update or
293 *             atomic LEB change
294 * @upd_received: how many bytes were already received for volume update or
295 *                atomic LEB change
296 * @upd_buf: update buffer which is used to collect update data or data for
297 *           atomic LEB change
298 *
299 * @eba_tbl: EBA table of this volume (LEB->PEB mapping)
300 * @checked: %1 if this static volume was checked
301 * @corrupted: %1 if the volume is corrupted (static volumes only)
302 * @upd_marker: %1 if the update marker is set for this volume
303 * @updating: %1 if the volume is being updated
304 * @changing_leb: %1 if the atomic LEB change ioctl command is in progress
305 * @direct_writes: %1 if direct writes are enabled for this volume
306 *
307 * The @corrupted field indicates that the volume's contents is corrupted.
308 * Since UBI protects only static volumes, this field is not relevant to
309 * dynamic volumes - it is user's responsibility to assure their data
310 * integrity.
311 *
312 * The @upd_marker flag indicates that this volume is either being updated at
313 * the moment or is damaged because of an unclean reboot.
314 */
315struct ubi_volume {
316	struct device dev;
317	struct cdev cdev;
318	struct ubi_device *ubi;
319	int vol_id;
320	int ref_count;
321	int readers;
322	int writers;
323	int exclusive;
324	int metaonly;
325
326	int reserved_pebs;
327	int vol_type;
328	int usable_leb_size;
329	int used_ebs;
330	int last_eb_bytes;
331	long long used_bytes;
332	int alignment;
333	int data_pad;
334	int name_len;
335	char name[UBI_VOL_NAME_MAX + 1];
336
337	int upd_ebs;
338	int ch_lnum;
339	long long upd_bytes;
340	long long upd_received;
341	void *upd_buf;
342
343	int *eba_tbl;
344	unsigned int checked:1;
345	unsigned int corrupted:1;
346	unsigned int upd_marker:1;
347	unsigned int updating:1;
348	unsigned int changing_leb:1;
349	unsigned int direct_writes:1;
350};
351
352/**
353 * struct ubi_volume_desc - UBI volume descriptor returned when it is opened.
354 * @vol: reference to the corresponding volume description object
355 * @mode: open mode (%UBI_READONLY, %UBI_READWRITE, %UBI_EXCLUSIVE
356 * or %UBI_METAONLY)
357 */
358struct ubi_volume_desc {
359	struct ubi_volume *vol;
360	int mode;
361};
362
363struct ubi_wl_entry;
364
365/**
366 * struct ubi_debug_info - debugging information for an UBI device.
367 *
368 * @chk_gen: if UBI general extra checks are enabled
369 * @chk_io: if UBI I/O extra checks are enabled
370 * @chk_fastmap: if UBI fastmap extra checks are enabled
371 * @disable_bgt: disable the background task for testing purposes
372 * @emulate_bitflips: emulate bit-flips for testing purposes
373 * @emulate_io_failures: emulate write/erase failures for testing purposes
374 * @emulate_power_cut: emulate power cut for testing purposes
375 * @power_cut_counter: count down for writes left until emulated power cut
376 * @power_cut_min: minimum number of writes before emulating a power cut
377 * @power_cut_max: maximum number of writes until emulating a power cut
378 * @dfs_dir_name: name of debugfs directory containing files of this UBI device
379 * @dfs_dir: direntry object of the UBI device debugfs directory
380 * @dfs_chk_gen: debugfs knob to enable UBI general extra checks
381 * @dfs_chk_io: debugfs knob to enable UBI I/O extra checks
382 * @dfs_chk_fastmap: debugfs knob to enable UBI fastmap extra checks
383 * @dfs_disable_bgt: debugfs knob to disable the background task
384 * @dfs_emulate_bitflips: debugfs knob to emulate bit-flips
385 * @dfs_emulate_io_failures: debugfs knob to emulate write/erase failures
386 * @dfs_emulate_power_cut: debugfs knob to emulate power cuts
387 * @dfs_power_cut_min: debugfs knob for minimum writes before power cut
388 * @dfs_power_cut_max: debugfs knob for maximum writes until power cut
389 */
390struct ubi_debug_info {
391	unsigned int chk_gen:1;
392	unsigned int chk_io:1;
393	unsigned int chk_fastmap:1;
394	unsigned int disable_bgt:1;
395	unsigned int emulate_bitflips:1;
396	unsigned int emulate_io_failures:1;
397	unsigned int emulate_power_cut:2;
398	unsigned int power_cut_counter;
399	unsigned int power_cut_min;
400	unsigned int power_cut_max;
401	char dfs_dir_name[UBI_DFS_DIR_LEN + 1];
402	struct dentry *dfs_dir;
403	struct dentry *dfs_chk_gen;
404	struct dentry *dfs_chk_io;
405	struct dentry *dfs_chk_fastmap;
406	struct dentry *dfs_disable_bgt;
407	struct dentry *dfs_emulate_bitflips;
408	struct dentry *dfs_emulate_io_failures;
409	struct dentry *dfs_emulate_power_cut;
410	struct dentry *dfs_power_cut_min;
411	struct dentry *dfs_power_cut_max;
412};
413
414/**
415 * struct ubi_device - UBI device description structure
416 * @dev: UBI device object to use the the Linux device model
417 * @cdev: character device object to create character device
418 * @ubi_num: UBI device number
419 * @ubi_name: UBI device name
420 * @vol_count: number of volumes in this UBI device
421 * @volumes: volumes of this UBI device
422 * @volumes_lock: protects @volumes, @rsvd_pebs, @avail_pebs, beb_rsvd_pebs,
423 *                @beb_rsvd_level, @bad_peb_count, @good_peb_count, @vol_count,
424 *                @vol->readers, @vol->writers, @vol->exclusive,
425 *                @vol->metaonly, @vol->ref_count, @vol->mapping and
426 *                @vol->eba_tbl.
427 * @ref_count: count of references on the UBI device
428 * @image_seq: image sequence number recorded on EC headers
429 *
430 * @rsvd_pebs: count of reserved physical eraseblocks
431 * @avail_pebs: count of available physical eraseblocks
432 * @beb_rsvd_pebs: how many physical eraseblocks are reserved for bad PEB
433 *                 handling
434 * @beb_rsvd_level: normal level of PEBs reserved for bad PEB handling
435 *
436 * @autoresize_vol_id: ID of the volume which has to be auto-resized at the end
437 *                     of UBI initialization
438 * @vtbl_slots: how many slots are available in the volume table
439 * @vtbl_size: size of the volume table in bytes
440 * @vtbl: in-RAM volume table copy
441 * @device_mutex: protects on-flash volume table and serializes volume
442 *                creation, deletion, update, re-size, re-name and set
443 *                property
444 *
445 * @max_ec: current highest erase counter value
446 * @mean_ec: current mean erase counter value
447 *
448 * @global_sqnum: global sequence number
449 * @ltree_lock: protects the lock tree and @global_sqnum
450 * @ltree: the lock tree
451 * @alc_mutex: serializes "atomic LEB change" operations
452 *
453 * @fm_disabled: non-zero if fastmap is disabled (default)
454 * @fm: in-memory data structure of the currently used fastmap
455 * @fm_pool: in-memory data structure of the fastmap pool
456 * @fm_wl_pool: in-memory data structure of the fastmap pool used by the WL
457 *		sub-system
458 * @fm_protect: serializes ubi_update_fastmap(), protects @fm_buf and makes sure
459 * that critical sections cannot be interrupted by ubi_update_fastmap()
460 * @fm_buf: vmalloc()'d buffer which holds the raw fastmap
461 * @fm_size: fastmap size in bytes
462 * @fm_eba_sem: allows ubi_update_fastmap() to block EBA table changes
463 * @fm_work: fastmap work queue
464 * @fm_work_scheduled: non-zero if fastmap work was scheduled
465 * @fast_attach: non-zero if UBI was attached by fastmap
466 *
467 * @used: RB-tree of used physical eraseblocks
468 * @erroneous: RB-tree of erroneous used physical eraseblocks
469 * @free: RB-tree of free physical eraseblocks
470 * @free_count: Contains the number of elements in @free
471 * @scrub: RB-tree of physical eraseblocks which need scrubbing
472 * @pq: protection queue (contain physical eraseblocks which are temporarily
473 *      protected from the wear-leveling worker)
474 * @pq_head: protection queue head
475 * @wl_lock: protects the @used, @free, @pq, @pq_head, @lookuptbl, @move_from,
476 *	     @move_to, @move_to_put @erase_pending, @wl_scheduled, @works,
477 *	     @erroneous, @erroneous_peb_count, @fm_work_scheduled, @fm_pool,
478 *	     and @fm_wl_pool fields
479 * @move_mutex: serializes eraseblock moves
480 * @work_sem: used to wait for all the scheduled works to finish and prevent
481 * new works from being submitted
482 * @wl_scheduled: non-zero if the wear-leveling was scheduled
483 * @lookuptbl: a table to quickly find a &struct ubi_wl_entry object for any
484 *             physical eraseblock
485 * @move_from: physical eraseblock from where the data is being moved
486 * @move_to: physical eraseblock where the data is being moved to
487 * @move_to_put: if the "to" PEB was put
488 * @works: list of pending works
489 * @works_count: count of pending works
490 * @bgt_thread: background thread description object
491 * @thread_enabled: if the background thread is enabled
492 * @bgt_name: background thread name
493 *
494 * @flash_size: underlying MTD device size (in bytes)
495 * @peb_count: count of physical eraseblocks on the MTD device
496 * @peb_size: physical eraseblock size
497 * @bad_peb_limit: top limit of expected bad physical eraseblocks
498 * @bad_peb_count: count of bad physical eraseblocks
499 * @good_peb_count: count of good physical eraseblocks
500 * @corr_peb_count: count of corrupted physical eraseblocks (preserved and not
501 *                  used by UBI)
502 * @erroneous_peb_count: count of erroneous physical eraseblocks in @erroneous
503 * @max_erroneous: maximum allowed amount of erroneous physical eraseblocks
504 * @min_io_size: minimal input/output unit size of the underlying MTD device
505 * @hdrs_min_io_size: minimal I/O unit size used for VID and EC headers
506 * @ro_mode: if the UBI device is in read-only mode
507 * @leb_size: logical eraseblock size
508 * @leb_start: starting offset of logical eraseblocks within physical
509 *             eraseblocks
510 * @ec_hdr_alsize: size of the EC header aligned to @hdrs_min_io_size
511 * @vid_hdr_alsize: size of the VID header aligned to @hdrs_min_io_size
512 * @vid_hdr_offset: starting offset of the volume identifier header (might be
513 *                  unaligned)
514 * @vid_hdr_aloffset: starting offset of the VID header aligned to
515 *                    @hdrs_min_io_size
516 * @vid_hdr_shift: contains @vid_hdr_offset - @vid_hdr_aloffset
517 * @bad_allowed: whether the MTD device admits of bad physical eraseblocks or
518 *               not
519 * @nor_flash: non-zero if working on top of NOR flash
520 * @max_write_size: maximum amount of bytes the underlying flash can write at a
521 *                  time (MTD write buffer size)
522 * @mtd: MTD device descriptor
523 *
524 * @peb_buf: a buffer of PEB size used for different purposes
525 * @buf_mutex: protects @peb_buf
526 * @ckvol_mutex: serializes static volume checking when opening
527 *
528 * @dbg: debugging information for this UBI device
529 */
530struct ubi_device {
531	struct cdev cdev;
532	struct device dev;
533	int ubi_num;
534	char ubi_name[sizeof(UBI_NAME_STR)+5];
535	int vol_count;
536	struct ubi_volume *volumes[UBI_MAX_VOLUMES+UBI_INT_VOL_COUNT];
537	spinlock_t volumes_lock;
538	int ref_count;
539	int image_seq;
540
541	int rsvd_pebs;
542	int avail_pebs;
543	int beb_rsvd_pebs;
544	int beb_rsvd_level;
545	int bad_peb_limit;
546
547	int autoresize_vol_id;
548	int vtbl_slots;
549	int vtbl_size;
550	struct ubi_vtbl_record *vtbl;
551	struct mutex device_mutex;
552
553	int max_ec;
554	/* Note, mean_ec is not updated run-time - should be fixed */
555	int mean_ec;
556
557	/* EBA sub-system's stuff */
558	unsigned long long global_sqnum;
559	spinlock_t ltree_lock;
560	struct rb_root ltree;
561	struct mutex alc_mutex;
562
563	/* Fastmap stuff */
564	int fm_disabled;
565	struct ubi_fastmap_layout *fm;
566	struct ubi_fm_pool fm_pool;
567	struct ubi_fm_pool fm_wl_pool;
568	struct rw_semaphore fm_eba_sem;
569	struct rw_semaphore fm_protect;
570	void *fm_buf;
571	size_t fm_size;
572	struct work_struct fm_work;
573	int fm_work_scheduled;
574	int fast_attach;
575
576	/* Wear-leveling sub-system's stuff */
577	struct rb_root used;
578	struct rb_root erroneous;
579	struct rb_root free;
580	int free_count;
581	struct rb_root scrub;
582	struct list_head pq[UBI_PROT_QUEUE_LEN];
583	int pq_head;
584	spinlock_t wl_lock;
585	struct mutex move_mutex;
586	struct rw_semaphore work_sem;
587	int wl_scheduled;
588	struct ubi_wl_entry **lookuptbl;
589	struct ubi_wl_entry *move_from;
590	struct ubi_wl_entry *move_to;
591	int move_to_put;
592	struct list_head works;
593	int works_count;
594	struct task_struct *bgt_thread;
595	int thread_enabled;
596	char bgt_name[sizeof(UBI_BGT_NAME_PATTERN)+2];
597
598	/* I/O sub-system's stuff */
599	long long flash_size;
600	int peb_count;
601	int peb_size;
602	int bad_peb_count;
603	int good_peb_count;
604	int corr_peb_count;
605	int erroneous_peb_count;
606	int max_erroneous;
607	int min_io_size;
608	int hdrs_min_io_size;
609	int ro_mode;
610	int leb_size;
611	int leb_start;
612	int ec_hdr_alsize;
613	int vid_hdr_alsize;
614	int vid_hdr_offset;
615	int vid_hdr_aloffset;
616	int vid_hdr_shift;
617	unsigned int bad_allowed:1;
618	unsigned int nor_flash:1;
619	int max_write_size;
620	struct mtd_info *mtd;
621
622	void *peb_buf;
623	struct mutex buf_mutex;
624	struct mutex ckvol_mutex;
625
626	struct ubi_debug_info dbg;
627};
628
629/**
630 * struct ubi_ainf_peb - attach information about a physical eraseblock.
631 * @ec: erase counter (%UBI_UNKNOWN if it is unknown)
632 * @pnum: physical eraseblock number
633 * @vol_id: ID of the volume this LEB belongs to
634 * @lnum: logical eraseblock number
635 * @scrub: if this physical eraseblock needs scrubbing
636 * @copy_flag: this LEB is a copy (@copy_flag is set in VID header of this LEB)
637 * @sqnum: sequence number
638 * @u: unions RB-tree or @list links
639 * @u.rb: link in the per-volume RB-tree of &struct ubi_ainf_peb objects
640 * @u.list: link in one of the eraseblock lists
641 *
642 * One object of this type is allocated for each physical eraseblock when
643 * attaching an MTD device. Note, if this PEB does not belong to any LEB /
644 * volume, the @vol_id and @lnum fields are initialized to %UBI_UNKNOWN.
645 */
646struct ubi_ainf_peb {
647	int ec;
648	int pnum;
649	int vol_id;
650	int lnum;
651	unsigned int scrub:1;
652	unsigned int copy_flag:1;
653	unsigned long long sqnum;
654	union {
655		struct rb_node rb;
656		struct list_head list;
657	} u;
658};
659
660/**
661 * struct ubi_ainf_volume - attaching information about a volume.
662 * @vol_id: volume ID
663 * @highest_lnum: highest logical eraseblock number in this volume
664 * @leb_count: number of logical eraseblocks in this volume
665 * @vol_type: volume type
666 * @used_ebs: number of used logical eraseblocks in this volume (only for
667 *            static volumes)
668 * @last_data_size: amount of data in the last logical eraseblock of this
669 *                  volume (always equivalent to the usable logical eraseblock
670 *                  size in case of dynamic volumes)
671 * @data_pad: how many bytes at the end of logical eraseblocks of this volume
672 *            are not used (due to volume alignment)
673 * @compat: compatibility flags of this volume
674 * @rb: link in the volume RB-tree
675 * @root: root of the RB-tree containing all the eraseblock belonging to this
676 *        volume (&struct ubi_ainf_peb objects)
677 *
678 * One object of this type is allocated for each volume when attaching an MTD
679 * device.
680 */
681struct ubi_ainf_volume {
682	int vol_id;
683	int highest_lnum;
684	int leb_count;
685	int vol_type;
686	int used_ebs;
687	int last_data_size;
688	int data_pad;
689	int compat;
690	struct rb_node rb;
691	struct rb_root root;
692};
693
694/**
695 * struct ubi_attach_info - MTD device attaching information.
696 * @volumes: root of the volume RB-tree
697 * @corr: list of corrupted physical eraseblocks
698 * @free: list of free physical eraseblocks
699 * @erase: list of physical eraseblocks which have to be erased
700 * @alien: list of physical eraseblocks which should not be used by UBI (e.g.,
701 *         those belonging to "preserve"-compatible internal volumes)
702 * @corr_peb_count: count of PEBs in the @corr list
703 * @empty_peb_count: count of PEBs which are presumably empty (contain only
704 *                   0xFF bytes)
705 * @alien_peb_count: count of PEBs in the @alien list
706 * @bad_peb_count: count of bad physical eraseblocks
707 * @maybe_bad_peb_count: count of bad physical eraseblocks which are not marked
708 *                       as bad yet, but which look like bad
709 * @vols_found: number of volumes found
710 * @highest_vol_id: highest volume ID
711 * @is_empty: flag indicating whether the MTD device is empty or not
712 * @min_ec: lowest erase counter value
713 * @max_ec: highest erase counter value
714 * @max_sqnum: highest sequence number value
715 * @mean_ec: mean erase counter value
716 * @ec_sum: a temporary variable used when calculating @mean_ec
717 * @ec_count: a temporary variable used when calculating @mean_ec
718 * @aeb_slab_cache: slab cache for &struct ubi_ainf_peb objects
719 *
720 * This data structure contains the result of attaching an MTD device and may
721 * be used by other UBI sub-systems to build final UBI data structures, further
722 * error-recovery and so on.
723 */
724struct ubi_attach_info {
725	struct rb_root volumes;
726	struct list_head corr;
727	struct list_head free;
728	struct list_head erase;
729	struct list_head alien;
730	int corr_peb_count;
731	int empty_peb_count;
732	int alien_peb_count;
733	int bad_peb_count;
734	int maybe_bad_peb_count;
735	int vols_found;
736	int highest_vol_id;
737	int is_empty;
738	int min_ec;
739	int max_ec;
740	unsigned long long max_sqnum;
741	int mean_ec;
742	uint64_t ec_sum;
743	int ec_count;
744	struct kmem_cache *aeb_slab_cache;
745};
746
747/**
748 * struct ubi_work - UBI work description data structure.
749 * @list: a link in the list of pending works
750 * @func: worker function
751 * @e: physical eraseblock to erase
752 * @vol_id: the volume ID on which this erasure is being performed
753 * @lnum: the logical eraseblock number
754 * @torture: if the physical eraseblock has to be tortured
755 * @anchor: produce a anchor PEB to by used by fastmap
756 *
757 * The @func pointer points to the worker function. If the @shutdown argument is
758 * not zero, the worker has to free the resources and exit immediately as the
759 * WL sub-system is shutting down.
760 * The worker has to return zero in case of success and a negative error code in
761 * case of failure.
762 */
763struct ubi_work {
764	struct list_head list;
765	int (*func)(struct ubi_device *ubi, struct ubi_work *wrk, int shutdown);
766	/* The below fields are only relevant to erasure works */
767	struct ubi_wl_entry *e;
768	int vol_id;
769	int lnum;
770	int torture;
771	int anchor;
772};
773
774#include "debug.h"
775
776extern struct kmem_cache *ubi_wl_entry_slab;
777extern const struct file_operations ubi_ctrl_cdev_operations;
778extern const struct file_operations ubi_cdev_operations;
779extern const struct file_operations ubi_vol_cdev_operations;
780extern struct class *ubi_class;
781extern struct mutex ubi_devices_mutex;
782extern struct blocking_notifier_head ubi_notifiers;
783
784/* attach.c */
785int ubi_add_to_av(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum,
786		  int ec, const struct ubi_vid_hdr *vid_hdr, int bitflips);
787struct ubi_ainf_volume *ubi_find_av(const struct ubi_attach_info *ai,
788				    int vol_id);
789void ubi_remove_av(struct ubi_attach_info *ai, struct ubi_ainf_volume *av);
790struct ubi_ainf_peb *ubi_early_get_peb(struct ubi_device *ubi,
791				       struct ubi_attach_info *ai);
792int ubi_attach(struct ubi_device *ubi, int force_scan);
793void ubi_destroy_ai(struct ubi_attach_info *ai);
794
795/* vtbl.c */
796int ubi_change_vtbl_record(struct ubi_device *ubi, int idx,
797			   struct ubi_vtbl_record *vtbl_rec);
798int ubi_vtbl_rename_volumes(struct ubi_device *ubi,
799			    struct list_head *rename_list);
800int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_attach_info *ai);
801
802/* vmt.c */
803int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req);
804int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl);
805int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs);
806int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list);
807int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol);
808void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol);
809
810/* upd.c */
811int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol,
812		     long long bytes);
813int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol,
814			 const void __user *buf, int count);
815int ubi_start_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
816			 const struct ubi_leb_change_req *req);
817int ubi_more_leb_change_data(struct ubi_device *ubi, struct ubi_volume *vol,
818			     const void __user *buf, int count);
819
820/* misc.c */
821int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf,
822		      int length);
823int ubi_check_volume(struct ubi_device *ubi, int vol_id);
824void ubi_update_reserved(struct ubi_device *ubi);
825void ubi_calculate_reserved(struct ubi_device *ubi);
826int ubi_check_pattern(const void *buf, uint8_t patt, int size);
827
828/* eba.c */
829int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol,
830		      int lnum);
831int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
832		     void *buf, int offset, int len, int check);
833int ubi_eba_read_leb_sg(struct ubi_device *ubi, struct ubi_volume *vol,
834			struct ubi_sgl *sgl, int lnum, int offset, int len,
835			int check);
836int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
837		      const void *buf, int offset, int len);
838int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol,
839			 int lnum, const void *buf, int len, int used_ebs);
840int ubi_eba_atomic_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
841			      int lnum, const void *buf, int len);
842int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
843		     struct ubi_vid_hdr *vid_hdr);
844int ubi_eba_init(struct ubi_device *ubi, struct ubi_attach_info *ai);
845unsigned long long ubi_next_sqnum(struct ubi_device *ubi);
846int self_check_eba(struct ubi_device *ubi, struct ubi_attach_info *ai_fastmap,
847		   struct ubi_attach_info *ai_scan);
848
849/* wl.c */
850int ubi_wl_get_peb(struct ubi_device *ubi);
851int ubi_wl_put_peb(struct ubi_device *ubi, int vol_id, int lnum,
852		   int pnum, int torture);
853int ubi_wl_flush(struct ubi_device *ubi, int vol_id, int lnum);
854int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum);
855int ubi_wl_init(struct ubi_device *ubi, struct ubi_attach_info *ai);
856void ubi_wl_close(struct ubi_device *ubi);
857int ubi_thread(void *u);
858struct ubi_wl_entry *ubi_wl_get_fm_peb(struct ubi_device *ubi, int anchor);
859int ubi_wl_put_fm_peb(struct ubi_device *ubi, struct ubi_wl_entry *used_e,
860		      int lnum, int torture);
861int ubi_is_erase_work(struct ubi_work *wrk);
862void ubi_refill_pools(struct ubi_device *ubi);
863int ubi_ensure_anchor_pebs(struct ubi_device *ubi);
864
865/* io.c */
866int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset,
867		int len);
868int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
869		 int len);
870int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture);
871int ubi_io_is_bad(const struct ubi_device *ubi, int pnum);
872int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum);
873int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum,
874		       struct ubi_ec_hdr *ec_hdr, int verbose);
875int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum,
876			struct ubi_ec_hdr *ec_hdr);
877int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum,
878			struct ubi_vid_hdr *vid_hdr, int verbose);
879int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum,
880			 struct ubi_vid_hdr *vid_hdr);
881
882/* build.c */
883int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
884		       int vid_hdr_offset, int max_beb_per1024);
885int ubi_detach_mtd_dev(int ubi_num, int anyway);
886struct ubi_device *ubi_get_device(int ubi_num);
887void ubi_put_device(struct ubi_device *ubi);
888struct ubi_device *ubi_get_by_major(int major);
889int ubi_major2num(int major);
890int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol,
891		      int ntype);
892int ubi_notify_all(struct ubi_device *ubi, int ntype,
893		   struct notifier_block *nb);
894int ubi_enumerate_volumes(struct notifier_block *nb);
895void ubi_free_internal_volumes(struct ubi_device *ubi);
896
897/* kapi.c */
898void ubi_do_get_device_info(struct ubi_device *ubi, struct ubi_device_info *di);
899void ubi_do_get_volume_info(struct ubi_device *ubi, struct ubi_volume *vol,
900			    struct ubi_volume_info *vi);
901/* scan.c */
902int ubi_compare_lebs(struct ubi_device *ubi, const struct ubi_ainf_peb *aeb,
903		      int pnum, const struct ubi_vid_hdr *vid_hdr);
904
905/* fastmap.c */
906#ifdef CONFIG_MTD_UBI_FASTMAP
907size_t ubi_calc_fm_size(struct ubi_device *ubi);
908int ubi_update_fastmap(struct ubi_device *ubi);
909int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
910		     int fm_anchor);
911#else
912static inline int ubi_update_fastmap(struct ubi_device *ubi) { return 0; }
913#endif
914
915/* block.c */
916#ifdef CONFIG_MTD_UBI_BLOCK
917int ubiblock_init(void);
918void ubiblock_exit(void);
919int ubiblock_create(struct ubi_volume_info *vi);
920int ubiblock_remove(struct ubi_volume_info *vi);
921#else
922static inline int ubiblock_init(void) { return 0; }
923static inline void ubiblock_exit(void) {}
924static inline int ubiblock_create(struct ubi_volume_info *vi)
925{
926	return -ENOSYS;
927}
928static inline int ubiblock_remove(struct ubi_volume_info *vi)
929{
930	return -ENOSYS;
931}
932#endif
933
934/*
935 * ubi_for_each_free_peb - walk the UBI free RB tree.
936 * @ubi: UBI device description object
937 * @e: a pointer to a ubi_wl_entry to use as cursor
938 * @pos: a pointer to RB-tree entry type to use as a loop counter
939 */
940#define ubi_for_each_free_peb(ubi, e, tmp_rb)	\
941	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->free, u.rb)
942
943/*
944 * ubi_for_each_used_peb - walk the UBI used RB tree.
945 * @ubi: UBI device description object
946 * @e: a pointer to a ubi_wl_entry to use as cursor
947 * @pos: a pointer to RB-tree entry type to use as a loop counter
948 */
949#define ubi_for_each_used_peb(ubi, e, tmp_rb)	\
950	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->used, u.rb)
951
952/*
953 * ubi_for_each_scub_peb - walk the UBI scub RB tree.
954 * @ubi: UBI device description object
955 * @e: a pointer to a ubi_wl_entry to use as cursor
956 * @pos: a pointer to RB-tree entry type to use as a loop counter
957 */
958#define ubi_for_each_scrub_peb(ubi, e, tmp_rb)	\
959	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->scrub, u.rb)
960
961/*
962 * ubi_for_each_protected_peb - walk the UBI protection queue.
963 * @ubi: UBI device description object
964 * @i: a integer used as counter
965 * @e: a pointer to a ubi_wl_entry to use as cursor
966 */
967#define ubi_for_each_protected_peb(ubi, i, e)	\
968	for ((i) = 0; (i) < UBI_PROT_QUEUE_LEN; (i)++)	\
969		list_for_each_entry((e), &(ubi->pq[(i)]), u.list)
970
971/*
972 * ubi_rb_for_each_entry - walk an RB-tree.
973 * @rb: a pointer to type 'struct rb_node' to use as a loop counter
974 * @pos: a pointer to RB-tree entry type to use as a loop counter
975 * @root: RB-tree's root
976 * @member: the name of the 'struct rb_node' within the RB-tree entry
977 */
978#define ubi_rb_for_each_entry(rb, pos, root, member)                         \
979	for (rb = rb_first(root),                                            \
980	     pos = (rb ? container_of(rb, typeof(*pos), member) : NULL);     \
981	     rb;                                                             \
982	     rb = rb_next(rb),                                               \
983	     pos = (rb ? container_of(rb, typeof(*pos), member) : NULL))
984
985/*
986 * ubi_move_aeb_to_list - move a PEB from the volume tree to a list.
987 *
988 * @av: volume attaching information
989 * @aeb: attaching eraseblock information
990 * @list: the list to move to
991 */
992static inline void ubi_move_aeb_to_list(struct ubi_ainf_volume *av,
993					 struct ubi_ainf_peb *aeb,
994					 struct list_head *list)
995{
996		rb_erase(&aeb->u.rb, &av->root);
997		list_add_tail(&aeb->u.list, list);
998}
999
1000/**
1001 * ubi_zalloc_vid_hdr - allocate a volume identifier header object.
1002 * @ubi: UBI device description object
1003 * @gfp_flags: GFP flags to allocate with
1004 *
1005 * This function returns a pointer to the newly allocated and zero-filled
1006 * volume identifier header object in case of success and %NULL in case of
1007 * failure.
1008 */
1009static inline struct ubi_vid_hdr *
1010ubi_zalloc_vid_hdr(const struct ubi_device *ubi, gfp_t gfp_flags)
1011{
1012	void *vid_hdr;
1013
1014	vid_hdr = kzalloc(ubi->vid_hdr_alsize, gfp_flags);
1015	if (!vid_hdr)
1016		return NULL;
1017
1018	/*
1019	 * VID headers may be stored at un-aligned flash offsets, so we shift
1020	 * the pointer.
1021	 */
1022	return vid_hdr + ubi->vid_hdr_shift;
1023}
1024
1025/**
1026 * ubi_free_vid_hdr - free a volume identifier header object.
1027 * @ubi: UBI device description object
1028 * @vid_hdr: the object to free
1029 */
1030static inline void ubi_free_vid_hdr(const struct ubi_device *ubi,
1031				    struct ubi_vid_hdr *vid_hdr)
1032{
1033	void *p = vid_hdr;
1034
1035	if (!p)
1036		return;
1037
1038	kfree(p - ubi->vid_hdr_shift);
1039}
1040
1041/*
1042 * This function is equivalent to 'ubi_io_read()', but @offset is relative to
1043 * the beginning of the logical eraseblock, not to the beginning of the
1044 * physical eraseblock.
1045 */
1046static inline int ubi_io_read_data(const struct ubi_device *ubi, void *buf,
1047				   int pnum, int offset, int len)
1048{
1049	ubi_assert(offset >= 0);
1050	return ubi_io_read(ubi, buf, pnum, offset + ubi->leb_start, len);
1051}
1052
1053/*
1054 * This function is equivalent to 'ubi_io_write()', but @offset is relative to
1055 * the beginning of the logical eraseblock, not to the beginning of the
1056 * physical eraseblock.
1057 */
1058static inline int ubi_io_write_data(struct ubi_device *ubi, const void *buf,
1059				    int pnum, int offset, int len)
1060{
1061	ubi_assert(offset >= 0);
1062	return ubi_io_write(ubi, buf, pnum, offset + ubi->leb_start, len);
1063}
1064
1065/**
1066 * ubi_ro_mode - switch to read-only mode.
1067 * @ubi: UBI device description object
1068 */
1069static inline void ubi_ro_mode(struct ubi_device *ubi)
1070{
1071	if (!ubi->ro_mode) {
1072		ubi->ro_mode = 1;
1073		ubi_warn(ubi, "switch to read-only mode");
1074		dump_stack();
1075	}
1076}
1077
1078/**
1079 * vol_id2idx - get table index by volume ID.
1080 * @ubi: UBI device description object
1081 * @vol_id: volume ID
1082 */
1083static inline int vol_id2idx(const struct ubi_device *ubi, int vol_id)
1084{
1085	if (vol_id >= UBI_INTERNAL_VOL_START)
1086		return vol_id - UBI_INTERNAL_VOL_START + ubi->vtbl_slots;
1087	else
1088		return vol_id;
1089}
1090
1091/**
1092 * idx2vol_id - get volume ID by table index.
1093 * @ubi: UBI device description object
1094 * @idx: table index
1095 */
1096static inline int idx2vol_id(const struct ubi_device *ubi, int idx)
1097{
1098	if (idx >= ubi->vtbl_slots)
1099		return idx - ubi->vtbl_slots + UBI_INTERNAL_VOL_START;
1100	else
1101		return idx;
1102}
1103
1104#endif /* !__UBI_UBI_H__ */
1105