xref: /openbmc/linux/drivers/mtd/ubi/ubi.h (revision 6dfcd296)
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 struct ubi_device;
53 
54 /* Normal UBI messages */
55 __printf(2, 3)
56 void ubi_msg(const struct ubi_device *ubi, const char *fmt, ...);
57 
58 /* UBI warning messages */
59 __printf(2, 3)
60 void ubi_warn(const struct ubi_device *ubi, const char *fmt, ...);
61 
62 /* UBI error messages */
63 __printf(2, 3)
64 void ubi_err(const struct ubi_device *ubi, const char *fmt, ...);
65 
66 /* Background thread name pattern */
67 #define UBI_BGT_NAME_PATTERN "ubi_bgt%dd"
68 
69 /*
70  * This marker in the EBA table means that the LEB is um-mapped.
71  * NOTE! It has to have the same value as %UBI_ALL.
72  */
73 #define UBI_LEB_UNMAPPED -1
74 
75 /*
76  * In case of errors, UBI tries to repeat the operation several times before
77  * returning error. The below constant defines how many times UBI re-tries.
78  */
79 #define UBI_IO_RETRIES 3
80 
81 /*
82  * Length of the protection queue. The length is effectively equivalent to the
83  * number of (global) erase cycles PEBs are protected from the wear-leveling
84  * worker.
85  */
86 #define UBI_PROT_QUEUE_LEN 10
87 
88 /* The volume ID/LEB number/erase counter is unknown */
89 #define UBI_UNKNOWN -1
90 
91 /*
92  * The UBI debugfs directory name pattern and maximum name length (3 for "ubi"
93  * + 2 for the number plus 1 for the trailing zero byte.
94  */
95 #define UBI_DFS_DIR_NAME "ubi%d"
96 #define UBI_DFS_DIR_LEN  (3 + 2 + 1)
97 
98 /*
99  * Error codes returned by the I/O sub-system.
100  *
101  * UBI_IO_FF: the read region of flash contains only 0xFFs
102  * UBI_IO_FF_BITFLIPS: the same as %UBI_IO_FF, but also also there was a data
103  *                     integrity error reported by the MTD driver
104  *                     (uncorrectable ECC error in case of NAND)
105  * UBI_IO_BAD_HDR: the EC or VID header is corrupted (bad magic or CRC)
106  * UBI_IO_BAD_HDR_EBADMSG: the same as %UBI_IO_BAD_HDR, but also there was a
107  *                         data integrity error reported by the MTD driver
108  *                         (uncorrectable ECC error in case of NAND)
109  * UBI_IO_BITFLIPS: bit-flips were detected and corrected
110  *
111  * Note, it is probably better to have bit-flip and ebadmsg as flags which can
112  * be or'ed with other error code. But this is a big change because there are
113  * may callers, so it does not worth the risk of introducing a bug
114  */
115 enum {
116 	UBI_IO_FF = 1,
117 	UBI_IO_FF_BITFLIPS,
118 	UBI_IO_BAD_HDR,
119 	UBI_IO_BAD_HDR_EBADMSG,
120 	UBI_IO_BITFLIPS,
121 };
122 
123 /*
124  * Return codes of the 'ubi_eba_copy_leb()' function.
125  *
126  * MOVE_CANCEL_RACE: canceled because the volume is being deleted, the source
127  *                   PEB was put meanwhile, or there is I/O on the source PEB
128  * MOVE_SOURCE_RD_ERR: canceled because there was a read error from the source
129  *                     PEB
130  * MOVE_TARGET_RD_ERR: canceled because there was a read error from the target
131  *                     PEB
132  * MOVE_TARGET_WR_ERR: canceled because there was a write error to the target
133  *                     PEB
134  * MOVE_TARGET_BITFLIPS: canceled because a bit-flip was detected in the
135  *                       target PEB
136  * MOVE_RETRY: retry scrubbing the PEB
137  */
138 enum {
139 	MOVE_CANCEL_RACE = 1,
140 	MOVE_SOURCE_RD_ERR,
141 	MOVE_TARGET_RD_ERR,
142 	MOVE_TARGET_WR_ERR,
143 	MOVE_TARGET_BITFLIPS,
144 	MOVE_RETRY,
145 };
146 
147 /*
148  * Return codes of the fastmap sub-system
149  *
150  * UBI_NO_FASTMAP: No fastmap super block was found
151  * UBI_BAD_FASTMAP: A fastmap was found but it's unusable
152  */
153 enum {
154 	UBI_NO_FASTMAP = 1,
155 	UBI_BAD_FASTMAP,
156 };
157 
158 /*
159  * Flags for emulate_power_cut in ubi_debug_info
160  *
161  * POWER_CUT_EC_WRITE: Emulate a power cut when writing an EC header
162  * POWER_CUT_VID_WRITE: Emulate a power cut when writing a VID header
163  */
164 enum {
165 	POWER_CUT_EC_WRITE = 0x01,
166 	POWER_CUT_VID_WRITE = 0x02,
167 };
168 
169 /**
170  * struct ubi_vid_io_buf - VID buffer used to read/write VID info to/from the
171  *			   flash.
172  * @hdr: a pointer to the VID header stored in buffer
173  * @buffer: underlying buffer
174  */
175 struct ubi_vid_io_buf {
176 	struct ubi_vid_hdr *hdr;
177 	void *buffer;
178 };
179 
180 /**
181  * struct ubi_wl_entry - wear-leveling entry.
182  * @u.rb: link in the corresponding (free/used) RB-tree
183  * @u.list: link in the protection queue
184  * @ec: erase counter
185  * @pnum: physical eraseblock number
186  *
187  * This data structure is used in the WL sub-system. Each physical eraseblock
188  * has a corresponding &struct wl_entry object which may be kept in different
189  * RB-trees. See WL sub-system for details.
190  */
191 struct ubi_wl_entry {
192 	union {
193 		struct rb_node rb;
194 		struct list_head list;
195 	} u;
196 	int ec;
197 	int pnum;
198 };
199 
200 /**
201  * struct ubi_ltree_entry - an entry in the lock tree.
202  * @rb: links RB-tree nodes
203  * @vol_id: volume ID of the locked logical eraseblock
204  * @lnum: locked logical eraseblock number
205  * @users: how many tasks are using this logical eraseblock or wait for it
206  * @mutex: read/write mutex to implement read/write access serialization to
207  *         the (@vol_id, @lnum) logical eraseblock
208  *
209  * This data structure is used in the EBA sub-system to implement per-LEB
210  * locking. When a logical eraseblock is being locked - corresponding
211  * &struct ubi_ltree_entry object is inserted to the lock tree (@ubi->ltree).
212  * See EBA sub-system for details.
213  */
214 struct ubi_ltree_entry {
215 	struct rb_node rb;
216 	int vol_id;
217 	int lnum;
218 	int users;
219 	struct rw_semaphore mutex;
220 };
221 
222 /**
223  * struct ubi_rename_entry - volume re-name description data structure.
224  * @new_name_len: new volume name length
225  * @new_name: new volume name
226  * @remove: if not zero, this volume should be removed, not re-named
227  * @desc: descriptor of the volume
228  * @list: links re-name entries into a list
229  *
230  * This data structure is utilized in the multiple volume re-name code. Namely,
231  * UBI first creates a list of &struct ubi_rename_entry objects from the
232  * &struct ubi_rnvol_req request object, and then utilizes this list to do all
233  * the job.
234  */
235 struct ubi_rename_entry {
236 	int new_name_len;
237 	char new_name[UBI_VOL_NAME_MAX + 1];
238 	int remove;
239 	struct ubi_volume_desc *desc;
240 	struct list_head list;
241 };
242 
243 struct ubi_volume_desc;
244 
245 /**
246  * struct ubi_fastmap_layout - in-memory fastmap data structure.
247  * @e: PEBs used by the current fastmap
248  * @to_be_tortured: if non-zero tortured this PEB
249  * @used_blocks: number of used PEBs
250  * @max_pool_size: maximal size of the user pool
251  * @max_wl_pool_size: maximal size of the pool used by the WL sub-system
252  */
253 struct ubi_fastmap_layout {
254 	struct ubi_wl_entry *e[UBI_FM_MAX_BLOCKS];
255 	int to_be_tortured[UBI_FM_MAX_BLOCKS];
256 	int used_blocks;
257 	int max_pool_size;
258 	int max_wl_pool_size;
259 };
260 
261 /**
262  * struct ubi_fm_pool - in-memory fastmap pool
263  * @pebs: PEBs in this pool
264  * @used: number of used PEBs
265  * @size: total number of PEBs in this pool
266  * @max_size: maximal size of the pool
267  *
268  * A pool gets filled with up to max_size.
269  * If all PEBs within the pool are used a new fastmap will be written
270  * to the flash and the pool gets refilled with empty PEBs.
271  *
272  */
273 struct ubi_fm_pool {
274 	int pebs[UBI_FM_MAX_POOL_SIZE];
275 	int used;
276 	int size;
277 	int max_size;
278 };
279 
280 /**
281  * struct ubi_eba_leb_desc - EBA logical eraseblock descriptor
282  * @lnum: the logical eraseblock number
283  * @pnum: the physical eraseblock where the LEB can be found
284  *
285  * This structure is here to hide EBA's internal from other part of the
286  * UBI implementation.
287  *
288  * One can query the position of a LEB by calling ubi_eba_get_ldesc().
289  */
290 struct ubi_eba_leb_desc {
291 	int lnum;
292 	int pnum;
293 };
294 
295 /**
296  * struct ubi_volume - UBI volume description data structure.
297  * @dev: device object to make use of the the Linux device model
298  * @cdev: character device object to create character device
299  * @ubi: reference to the UBI device description object
300  * @vol_id: volume ID
301  * @ref_count: volume reference count
302  * @readers: number of users holding this volume in read-only mode
303  * @writers: number of users holding this volume in read-write mode
304  * @exclusive: whether somebody holds this volume in exclusive mode
305  * @metaonly: whether somebody is altering only meta data of this volume
306  *
307  * @reserved_pebs: how many physical eraseblocks are reserved for this volume
308  * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
309  * @usable_leb_size: logical eraseblock size without padding
310  * @used_ebs: how many logical eraseblocks in this volume contain data
311  * @last_eb_bytes: how many bytes are stored in the last logical eraseblock
312  * @used_bytes: how many bytes of data this volume contains
313  * @alignment: volume alignment
314  * @data_pad: how many bytes are not used at the end of physical eraseblocks to
315  *            satisfy the requested alignment
316  * @name_len: volume name length
317  * @name: volume name
318  *
319  * @upd_ebs: how many eraseblocks are expected to be updated
320  * @ch_lnum: LEB number which is being changing by the atomic LEB change
321  *           operation
322  * @upd_bytes: how many bytes are expected to be received for volume update or
323  *             atomic LEB change
324  * @upd_received: how many bytes were already received for volume update or
325  *                atomic LEB change
326  * @upd_buf: update buffer which is used to collect update data or data for
327  *           atomic LEB change
328  *
329  * @eba_tbl: EBA table of this volume (LEB->PEB mapping)
330  * @checked: %1 if this static volume was checked
331  * @corrupted: %1 if the volume is corrupted (static volumes only)
332  * @upd_marker: %1 if the update marker is set for this volume
333  * @updating: %1 if the volume is being updated
334  * @changing_leb: %1 if the atomic LEB change ioctl command is in progress
335  * @direct_writes: %1 if direct writes are enabled for this volume
336  *
337  * The @corrupted field indicates that the volume's contents is corrupted.
338  * Since UBI protects only static volumes, this field is not relevant to
339  * dynamic volumes - it is user's responsibility to assure their data
340  * integrity.
341  *
342  * The @upd_marker flag indicates that this volume is either being updated at
343  * the moment or is damaged because of an unclean reboot.
344  */
345 struct ubi_volume {
346 	struct device dev;
347 	struct cdev cdev;
348 	struct ubi_device *ubi;
349 	int vol_id;
350 	int ref_count;
351 	int readers;
352 	int writers;
353 	int exclusive;
354 	int metaonly;
355 
356 	int reserved_pebs;
357 	int vol_type;
358 	int usable_leb_size;
359 	int used_ebs;
360 	int last_eb_bytes;
361 	long long used_bytes;
362 	int alignment;
363 	int data_pad;
364 	int name_len;
365 	char name[UBI_VOL_NAME_MAX + 1];
366 
367 	int upd_ebs;
368 	int ch_lnum;
369 	long long upd_bytes;
370 	long long upd_received;
371 	void *upd_buf;
372 
373 	struct ubi_eba_table *eba_tbl;
374 	unsigned int checked:1;
375 	unsigned int corrupted:1;
376 	unsigned int upd_marker:1;
377 	unsigned int updating:1;
378 	unsigned int changing_leb:1;
379 	unsigned int direct_writes:1;
380 };
381 
382 /**
383  * struct ubi_volume_desc - UBI volume descriptor returned when it is opened.
384  * @vol: reference to the corresponding volume description object
385  * @mode: open mode (%UBI_READONLY, %UBI_READWRITE, %UBI_EXCLUSIVE
386  * or %UBI_METAONLY)
387  */
388 struct ubi_volume_desc {
389 	struct ubi_volume *vol;
390 	int mode;
391 };
392 
393 struct ubi_wl_entry;
394 
395 /**
396  * struct ubi_debug_info - debugging information for an UBI device.
397  *
398  * @chk_gen: if UBI general extra checks are enabled
399  * @chk_io: if UBI I/O extra checks are enabled
400  * @chk_fastmap: if UBI fastmap extra checks are enabled
401  * @disable_bgt: disable the background task for testing purposes
402  * @emulate_bitflips: emulate bit-flips for testing purposes
403  * @emulate_io_failures: emulate write/erase failures for testing purposes
404  * @emulate_power_cut: emulate power cut for testing purposes
405  * @power_cut_counter: count down for writes left until emulated power cut
406  * @power_cut_min: minimum number of writes before emulating a power cut
407  * @power_cut_max: maximum number of writes until emulating a power cut
408  * @dfs_dir_name: name of debugfs directory containing files of this UBI device
409  * @dfs_dir: direntry object of the UBI device debugfs directory
410  * @dfs_chk_gen: debugfs knob to enable UBI general extra checks
411  * @dfs_chk_io: debugfs knob to enable UBI I/O extra checks
412  * @dfs_chk_fastmap: debugfs knob to enable UBI fastmap extra checks
413  * @dfs_disable_bgt: debugfs knob to disable the background task
414  * @dfs_emulate_bitflips: debugfs knob to emulate bit-flips
415  * @dfs_emulate_io_failures: debugfs knob to emulate write/erase failures
416  * @dfs_emulate_power_cut: debugfs knob to emulate power cuts
417  * @dfs_power_cut_min: debugfs knob for minimum writes before power cut
418  * @dfs_power_cut_max: debugfs knob for maximum writes until power cut
419  */
420 struct ubi_debug_info {
421 	unsigned int chk_gen:1;
422 	unsigned int chk_io:1;
423 	unsigned int chk_fastmap:1;
424 	unsigned int disable_bgt:1;
425 	unsigned int emulate_bitflips:1;
426 	unsigned int emulate_io_failures:1;
427 	unsigned int emulate_power_cut:2;
428 	unsigned int power_cut_counter;
429 	unsigned int power_cut_min;
430 	unsigned int power_cut_max;
431 	char dfs_dir_name[UBI_DFS_DIR_LEN + 1];
432 	struct dentry *dfs_dir;
433 	struct dentry *dfs_chk_gen;
434 	struct dentry *dfs_chk_io;
435 	struct dentry *dfs_chk_fastmap;
436 	struct dentry *dfs_disable_bgt;
437 	struct dentry *dfs_emulate_bitflips;
438 	struct dentry *dfs_emulate_io_failures;
439 	struct dentry *dfs_emulate_power_cut;
440 	struct dentry *dfs_power_cut_min;
441 	struct dentry *dfs_power_cut_max;
442 };
443 
444 /**
445  * struct ubi_device - UBI device description structure
446  * @dev: UBI device object to use the the Linux device model
447  * @cdev: character device object to create character device
448  * @ubi_num: UBI device number
449  * @ubi_name: UBI device name
450  * @vol_count: number of volumes in this UBI device
451  * @volumes: volumes of this UBI device
452  * @volumes_lock: protects @volumes, @rsvd_pebs, @avail_pebs, beb_rsvd_pebs,
453  *                @beb_rsvd_level, @bad_peb_count, @good_peb_count, @vol_count,
454  *                @vol->readers, @vol->writers, @vol->exclusive,
455  *                @vol->metaonly, @vol->ref_count, @vol->mapping and
456  *                @vol->eba_tbl.
457  * @ref_count: count of references on the UBI device
458  * @image_seq: image sequence number recorded on EC headers
459  *
460  * @rsvd_pebs: count of reserved physical eraseblocks
461  * @avail_pebs: count of available physical eraseblocks
462  * @beb_rsvd_pebs: how many physical eraseblocks are reserved for bad PEB
463  *                 handling
464  * @beb_rsvd_level: normal level of PEBs reserved for bad PEB handling
465  *
466  * @autoresize_vol_id: ID of the volume which has to be auto-resized at the end
467  *                     of UBI initialization
468  * @vtbl_slots: how many slots are available in the volume table
469  * @vtbl_size: size of the volume table in bytes
470  * @vtbl: in-RAM volume table copy
471  * @device_mutex: protects on-flash volume table and serializes volume
472  *                creation, deletion, update, re-size, re-name and set
473  *                property
474  *
475  * @max_ec: current highest erase counter value
476  * @mean_ec: current mean erase counter value
477  *
478  * @global_sqnum: global sequence number
479  * @ltree_lock: protects the lock tree and @global_sqnum
480  * @ltree: the lock tree
481  * @alc_mutex: serializes "atomic LEB change" operations
482  *
483  * @fm_disabled: non-zero if fastmap is disabled (default)
484  * @fm: in-memory data structure of the currently used fastmap
485  * @fm_pool: in-memory data structure of the fastmap pool
486  * @fm_wl_pool: in-memory data structure of the fastmap pool used by the WL
487  *		sub-system
488  * @fm_protect: serializes ubi_update_fastmap(), protects @fm_buf and makes sure
489  * that critical sections cannot be interrupted by ubi_update_fastmap()
490  * @fm_buf: vmalloc()'d buffer which holds the raw fastmap
491  * @fm_size: fastmap size in bytes
492  * @fm_eba_sem: allows ubi_update_fastmap() to block EBA table changes
493  * @fm_work: fastmap work queue
494  * @fm_work_scheduled: non-zero if fastmap work was scheduled
495  * @fast_attach: non-zero if UBI was attached by fastmap
496  *
497  * @used: RB-tree of used physical eraseblocks
498  * @erroneous: RB-tree of erroneous used physical eraseblocks
499  * @free: RB-tree of free physical eraseblocks
500  * @free_count: Contains the number of elements in @free
501  * @scrub: RB-tree of physical eraseblocks which need scrubbing
502  * @pq: protection queue (contain physical eraseblocks which are temporarily
503  *      protected from the wear-leveling worker)
504  * @pq_head: protection queue head
505  * @wl_lock: protects the @used, @free, @pq, @pq_head, @lookuptbl, @move_from,
506  *	     @move_to, @move_to_put @erase_pending, @wl_scheduled, @works,
507  *	     @erroneous, @erroneous_peb_count, @fm_work_scheduled, @fm_pool,
508  *	     and @fm_wl_pool fields
509  * @move_mutex: serializes eraseblock moves
510  * @work_sem: used to wait for all the scheduled works to finish and prevent
511  * new works from being submitted
512  * @wl_scheduled: non-zero if the wear-leveling was scheduled
513  * @lookuptbl: a table to quickly find a &struct ubi_wl_entry object for any
514  *             physical eraseblock
515  * @move_from: physical eraseblock from where the data is being moved
516  * @move_to: physical eraseblock where the data is being moved to
517  * @move_to_put: if the "to" PEB was put
518  * @works: list of pending works
519  * @works_count: count of pending works
520  * @bgt_thread: background thread description object
521  * @thread_enabled: if the background thread is enabled
522  * @bgt_name: background thread name
523  *
524  * @flash_size: underlying MTD device size (in bytes)
525  * @peb_count: count of physical eraseblocks on the MTD device
526  * @peb_size: physical eraseblock size
527  * @bad_peb_limit: top limit of expected bad physical eraseblocks
528  * @bad_peb_count: count of bad physical eraseblocks
529  * @good_peb_count: count of good physical eraseblocks
530  * @corr_peb_count: count of corrupted physical eraseblocks (preserved and not
531  *                  used by UBI)
532  * @erroneous_peb_count: count of erroneous physical eraseblocks in @erroneous
533  * @max_erroneous: maximum allowed amount of erroneous physical eraseblocks
534  * @min_io_size: minimal input/output unit size of the underlying MTD device
535  * @hdrs_min_io_size: minimal I/O unit size used for VID and EC headers
536  * @ro_mode: if the UBI device is in read-only mode
537  * @leb_size: logical eraseblock size
538  * @leb_start: starting offset of logical eraseblocks within physical
539  *             eraseblocks
540  * @ec_hdr_alsize: size of the EC header aligned to @hdrs_min_io_size
541  * @vid_hdr_alsize: size of the VID header aligned to @hdrs_min_io_size
542  * @vid_hdr_offset: starting offset of the volume identifier header (might be
543  *                  unaligned)
544  * @vid_hdr_aloffset: starting offset of the VID header aligned to
545  *                    @hdrs_min_io_size
546  * @vid_hdr_shift: contains @vid_hdr_offset - @vid_hdr_aloffset
547  * @bad_allowed: whether the MTD device admits of bad physical eraseblocks or
548  *               not
549  * @nor_flash: non-zero if working on top of NOR flash
550  * @max_write_size: maximum amount of bytes the underlying flash can write at a
551  *                  time (MTD write buffer size)
552  * @mtd: MTD device descriptor
553  *
554  * @peb_buf: a buffer of PEB size used for different purposes
555  * @buf_mutex: protects @peb_buf
556  * @ckvol_mutex: serializes static volume checking when opening
557  *
558  * @dbg: debugging information for this UBI device
559  */
560 struct ubi_device {
561 	struct cdev cdev;
562 	struct device dev;
563 	int ubi_num;
564 	char ubi_name[sizeof(UBI_NAME_STR)+5];
565 	int vol_count;
566 	struct ubi_volume *volumes[UBI_MAX_VOLUMES+UBI_INT_VOL_COUNT];
567 	spinlock_t volumes_lock;
568 	int ref_count;
569 	int image_seq;
570 
571 	int rsvd_pebs;
572 	int avail_pebs;
573 	int beb_rsvd_pebs;
574 	int beb_rsvd_level;
575 	int bad_peb_limit;
576 
577 	int autoresize_vol_id;
578 	int vtbl_slots;
579 	int vtbl_size;
580 	struct ubi_vtbl_record *vtbl;
581 	struct mutex device_mutex;
582 
583 	int max_ec;
584 	/* Note, mean_ec is not updated run-time - should be fixed */
585 	int mean_ec;
586 
587 	/* EBA sub-system's stuff */
588 	unsigned long long global_sqnum;
589 	spinlock_t ltree_lock;
590 	struct rb_root ltree;
591 	struct mutex alc_mutex;
592 
593 	/* Fastmap stuff */
594 	int fm_disabled;
595 	struct ubi_fastmap_layout *fm;
596 	struct ubi_fm_pool fm_pool;
597 	struct ubi_fm_pool fm_wl_pool;
598 	struct rw_semaphore fm_eba_sem;
599 	struct rw_semaphore fm_protect;
600 	void *fm_buf;
601 	size_t fm_size;
602 	struct work_struct fm_work;
603 	int fm_work_scheduled;
604 	int fast_attach;
605 
606 	/* Wear-leveling sub-system's stuff */
607 	struct rb_root used;
608 	struct rb_root erroneous;
609 	struct rb_root free;
610 	int free_count;
611 	struct rb_root scrub;
612 	struct list_head pq[UBI_PROT_QUEUE_LEN];
613 	int pq_head;
614 	spinlock_t wl_lock;
615 	struct mutex move_mutex;
616 	struct rw_semaphore work_sem;
617 	int wl_scheduled;
618 	struct ubi_wl_entry **lookuptbl;
619 	struct ubi_wl_entry *move_from;
620 	struct ubi_wl_entry *move_to;
621 	int move_to_put;
622 	struct list_head works;
623 	int works_count;
624 	struct task_struct *bgt_thread;
625 	int thread_enabled;
626 	char bgt_name[sizeof(UBI_BGT_NAME_PATTERN)+2];
627 
628 	/* I/O sub-system's stuff */
629 	long long flash_size;
630 	int peb_count;
631 	int peb_size;
632 	int bad_peb_count;
633 	int good_peb_count;
634 	int corr_peb_count;
635 	int erroneous_peb_count;
636 	int max_erroneous;
637 	int min_io_size;
638 	int hdrs_min_io_size;
639 	int ro_mode;
640 	int leb_size;
641 	int leb_start;
642 	int ec_hdr_alsize;
643 	int vid_hdr_alsize;
644 	int vid_hdr_offset;
645 	int vid_hdr_aloffset;
646 	int vid_hdr_shift;
647 	unsigned int bad_allowed:1;
648 	unsigned int nor_flash:1;
649 	int max_write_size;
650 	struct mtd_info *mtd;
651 
652 	void *peb_buf;
653 	struct mutex buf_mutex;
654 	struct mutex ckvol_mutex;
655 
656 	struct ubi_debug_info dbg;
657 };
658 
659 /**
660  * struct ubi_ainf_peb - attach information about a physical eraseblock.
661  * @ec: erase counter (%UBI_UNKNOWN if it is unknown)
662  * @pnum: physical eraseblock number
663  * @vol_id: ID of the volume this LEB belongs to
664  * @lnum: logical eraseblock number
665  * @scrub: if this physical eraseblock needs scrubbing
666  * @copy_flag: this LEB is a copy (@copy_flag is set in VID header of this LEB)
667  * @sqnum: sequence number
668  * @u: unions RB-tree or @list links
669  * @u.rb: link in the per-volume RB-tree of &struct ubi_ainf_peb objects
670  * @u.list: link in one of the eraseblock lists
671  *
672  * One object of this type is allocated for each physical eraseblock when
673  * attaching an MTD device. Note, if this PEB does not belong to any LEB /
674  * volume, the @vol_id and @lnum fields are initialized to %UBI_UNKNOWN.
675  */
676 struct ubi_ainf_peb {
677 	int ec;
678 	int pnum;
679 	int vol_id;
680 	int lnum;
681 	unsigned int scrub:1;
682 	unsigned int copy_flag:1;
683 	unsigned long long sqnum;
684 	union {
685 		struct rb_node rb;
686 		struct list_head list;
687 	} u;
688 };
689 
690 /**
691  * struct ubi_ainf_volume - attaching information about a volume.
692  * @vol_id: volume ID
693  * @highest_lnum: highest logical eraseblock number in this volume
694  * @leb_count: number of logical eraseblocks in this volume
695  * @vol_type: volume type
696  * @used_ebs: number of used logical eraseblocks in this volume (only for
697  *            static volumes)
698  * @last_data_size: amount of data in the last logical eraseblock of this
699  *                  volume (always equivalent to the usable logical eraseblock
700  *                  size in case of dynamic volumes)
701  * @data_pad: how many bytes at the end of logical eraseblocks of this volume
702  *            are not used (due to volume alignment)
703  * @compat: compatibility flags of this volume
704  * @rb: link in the volume RB-tree
705  * @root: root of the RB-tree containing all the eraseblock belonging to this
706  *        volume (&struct ubi_ainf_peb objects)
707  *
708  * One object of this type is allocated for each volume when attaching an MTD
709  * device.
710  */
711 struct ubi_ainf_volume {
712 	int vol_id;
713 	int highest_lnum;
714 	int leb_count;
715 	int vol_type;
716 	int used_ebs;
717 	int last_data_size;
718 	int data_pad;
719 	int compat;
720 	struct rb_node rb;
721 	struct rb_root root;
722 };
723 
724 /**
725  * struct ubi_attach_info - MTD device attaching information.
726  * @volumes: root of the volume RB-tree
727  * @corr: list of corrupted physical eraseblocks
728  * @free: list of free physical eraseblocks
729  * @erase: list of physical eraseblocks which have to be erased
730  * @alien: list of physical eraseblocks which should not be used by UBI (e.g.,
731  *         those belonging to "preserve"-compatible internal volumes)
732  * @fastmap: list of physical eraseblocks which relate to fastmap (e.g.,
733  *           eraseblocks of the current and not yet erased old fastmap blocks)
734  * @corr_peb_count: count of PEBs in the @corr list
735  * @empty_peb_count: count of PEBs which are presumably empty (contain only
736  *                   0xFF bytes)
737  * @alien_peb_count: count of PEBs in the @alien list
738  * @bad_peb_count: count of bad physical eraseblocks
739  * @maybe_bad_peb_count: count of bad physical eraseblocks which are not marked
740  *                       as bad yet, but which look like bad
741  * @vols_found: number of volumes found
742  * @highest_vol_id: highest volume ID
743  * @is_empty: flag indicating whether the MTD device is empty or not
744  * @force_full_scan: flag indicating whether we need to do a full scan and drop
745 		     all existing Fastmap data structures
746  * @min_ec: lowest erase counter value
747  * @max_ec: highest erase counter value
748  * @max_sqnum: highest sequence number value
749  * @mean_ec: mean erase counter value
750  * @ec_sum: a temporary variable used when calculating @mean_ec
751  * @ec_count: a temporary variable used when calculating @mean_ec
752  * @aeb_slab_cache: slab cache for &struct ubi_ainf_peb objects
753  * @ech: temporary EC header. Only available during scan
754  * @vidh: temporary VID buffer. Only available during scan
755  *
756  * This data structure contains the result of attaching an MTD device and may
757  * be used by other UBI sub-systems to build final UBI data structures, further
758  * error-recovery and so on.
759  */
760 struct ubi_attach_info {
761 	struct rb_root volumes;
762 	struct list_head corr;
763 	struct list_head free;
764 	struct list_head erase;
765 	struct list_head alien;
766 	struct list_head fastmap;
767 	int corr_peb_count;
768 	int empty_peb_count;
769 	int alien_peb_count;
770 	int bad_peb_count;
771 	int maybe_bad_peb_count;
772 	int vols_found;
773 	int highest_vol_id;
774 	int is_empty;
775 	int force_full_scan;
776 	int min_ec;
777 	int max_ec;
778 	unsigned long long max_sqnum;
779 	int mean_ec;
780 	uint64_t ec_sum;
781 	int ec_count;
782 	struct kmem_cache *aeb_slab_cache;
783 	struct ubi_ec_hdr *ech;
784 	struct ubi_vid_io_buf *vidb;
785 };
786 
787 /**
788  * struct ubi_work - UBI work description data structure.
789  * @list: a link in the list of pending works
790  * @func: worker function
791  * @e: physical eraseblock to erase
792  * @vol_id: the volume ID on which this erasure is being performed
793  * @lnum: the logical eraseblock number
794  * @torture: if the physical eraseblock has to be tortured
795  * @anchor: produce a anchor PEB to by used by fastmap
796  *
797  * The @func pointer points to the worker function. If the @shutdown argument is
798  * not zero, the worker has to free the resources and exit immediately as the
799  * WL sub-system is shutting down.
800  * The worker has to return zero in case of success and a negative error code in
801  * case of failure.
802  */
803 struct ubi_work {
804 	struct list_head list;
805 	int (*func)(struct ubi_device *ubi, struct ubi_work *wrk, int shutdown);
806 	/* The below fields are only relevant to erasure works */
807 	struct ubi_wl_entry *e;
808 	int vol_id;
809 	int lnum;
810 	int torture;
811 	int anchor;
812 };
813 
814 #include "debug.h"
815 
816 extern struct kmem_cache *ubi_wl_entry_slab;
817 extern const struct file_operations ubi_ctrl_cdev_operations;
818 extern const struct file_operations ubi_cdev_operations;
819 extern const struct file_operations ubi_vol_cdev_operations;
820 extern struct class ubi_class;
821 extern struct mutex ubi_devices_mutex;
822 extern struct blocking_notifier_head ubi_notifiers;
823 
824 /* attach.c */
825 struct ubi_ainf_peb *ubi_alloc_aeb(struct ubi_attach_info *ai, int pnum,
826 				   int ec);
827 void ubi_free_aeb(struct ubi_attach_info *ai, struct ubi_ainf_peb *aeb);
828 int ubi_add_to_av(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum,
829 		  int ec, const struct ubi_vid_hdr *vid_hdr, int bitflips);
830 struct ubi_ainf_volume *ubi_add_av(struct ubi_attach_info *ai, int vol_id);
831 struct ubi_ainf_volume *ubi_find_av(const struct ubi_attach_info *ai,
832 				    int vol_id);
833 void ubi_remove_av(struct ubi_attach_info *ai, struct ubi_ainf_volume *av);
834 struct ubi_ainf_peb *ubi_early_get_peb(struct ubi_device *ubi,
835 				       struct ubi_attach_info *ai);
836 int ubi_attach(struct ubi_device *ubi, int force_scan);
837 void ubi_destroy_ai(struct ubi_attach_info *ai);
838 
839 /* vtbl.c */
840 int ubi_change_vtbl_record(struct ubi_device *ubi, int idx,
841 			   struct ubi_vtbl_record *vtbl_rec);
842 int ubi_vtbl_rename_volumes(struct ubi_device *ubi,
843 			    struct list_head *rename_list);
844 int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_attach_info *ai);
845 
846 /* vmt.c */
847 int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req);
848 int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl);
849 int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs);
850 int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list);
851 int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol);
852 void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol);
853 
854 /* upd.c */
855 int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol,
856 		     long long bytes);
857 int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol,
858 			 const void __user *buf, int count);
859 int ubi_start_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
860 			 const struct ubi_leb_change_req *req);
861 int ubi_more_leb_change_data(struct ubi_device *ubi, struct ubi_volume *vol,
862 			     const void __user *buf, int count);
863 
864 /* misc.c */
865 int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf,
866 		      int length);
867 int ubi_check_volume(struct ubi_device *ubi, int vol_id);
868 void ubi_update_reserved(struct ubi_device *ubi);
869 void ubi_calculate_reserved(struct ubi_device *ubi);
870 int ubi_check_pattern(const void *buf, uint8_t patt, int size);
871 
872 static inline bool ubi_leb_valid(struct ubi_volume *vol, int lnum)
873 {
874 	return lnum >= 0 && lnum < vol->reserved_pebs;
875 }
876 
877 /* eba.c */
878 struct ubi_eba_table *ubi_eba_create_table(struct ubi_volume *vol,
879 					   int nentries);
880 void ubi_eba_destroy_table(struct ubi_eba_table *tbl);
881 void ubi_eba_copy_table(struct ubi_volume *vol, struct ubi_eba_table *dst,
882 			int nentries);
883 void ubi_eba_replace_table(struct ubi_volume *vol, struct ubi_eba_table *tbl);
884 void ubi_eba_get_ldesc(struct ubi_volume *vol, int lnum,
885 		       struct ubi_eba_leb_desc *ldesc);
886 bool ubi_eba_is_mapped(struct ubi_volume *vol, int lnum);
887 int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol,
888 		      int lnum);
889 int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
890 		     void *buf, int offset, int len, int check);
891 int ubi_eba_read_leb_sg(struct ubi_device *ubi, struct ubi_volume *vol,
892 			struct ubi_sgl *sgl, int lnum, int offset, int len,
893 			int check);
894 int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
895 		      const void *buf, int offset, int len);
896 int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol,
897 			 int lnum, const void *buf, int len, int used_ebs);
898 int ubi_eba_atomic_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
899 			      int lnum, const void *buf, int len);
900 int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
901 		     struct ubi_vid_io_buf *vidb);
902 int ubi_eba_init(struct ubi_device *ubi, struct ubi_attach_info *ai);
903 unsigned long long ubi_next_sqnum(struct ubi_device *ubi);
904 int self_check_eba(struct ubi_device *ubi, struct ubi_attach_info *ai_fastmap,
905 		   struct ubi_attach_info *ai_scan);
906 
907 /* wl.c */
908 int ubi_wl_get_peb(struct ubi_device *ubi);
909 int ubi_wl_put_peb(struct ubi_device *ubi, int vol_id, int lnum,
910 		   int pnum, int torture);
911 int ubi_wl_flush(struct ubi_device *ubi, int vol_id, int lnum);
912 int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum);
913 int ubi_wl_init(struct ubi_device *ubi, struct ubi_attach_info *ai);
914 void ubi_wl_close(struct ubi_device *ubi);
915 int ubi_thread(void *u);
916 struct ubi_wl_entry *ubi_wl_get_fm_peb(struct ubi_device *ubi, int anchor);
917 int ubi_wl_put_fm_peb(struct ubi_device *ubi, struct ubi_wl_entry *used_e,
918 		      int lnum, int torture);
919 int ubi_is_erase_work(struct ubi_work *wrk);
920 void ubi_refill_pools(struct ubi_device *ubi);
921 int ubi_ensure_anchor_pebs(struct ubi_device *ubi);
922 
923 /* io.c */
924 int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset,
925 		int len);
926 int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
927 		 int len);
928 int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture);
929 int ubi_io_is_bad(const struct ubi_device *ubi, int pnum);
930 int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum);
931 int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum,
932 		       struct ubi_ec_hdr *ec_hdr, int verbose);
933 int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum,
934 			struct ubi_ec_hdr *ec_hdr);
935 int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum,
936 			struct ubi_vid_io_buf *vidb, int verbose);
937 int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum,
938 			 struct ubi_vid_io_buf *vidb);
939 
940 /* build.c */
941 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
942 		       int vid_hdr_offset, int max_beb_per1024);
943 int ubi_detach_mtd_dev(int ubi_num, int anyway);
944 struct ubi_device *ubi_get_device(int ubi_num);
945 void ubi_put_device(struct ubi_device *ubi);
946 struct ubi_device *ubi_get_by_major(int major);
947 int ubi_major2num(int major);
948 int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol,
949 		      int ntype);
950 int ubi_notify_all(struct ubi_device *ubi, int ntype,
951 		   struct notifier_block *nb);
952 int ubi_enumerate_volumes(struct notifier_block *nb);
953 void ubi_free_internal_volumes(struct ubi_device *ubi);
954 
955 /* kapi.c */
956 void ubi_do_get_device_info(struct ubi_device *ubi, struct ubi_device_info *di);
957 void ubi_do_get_volume_info(struct ubi_device *ubi, struct ubi_volume *vol,
958 			    struct ubi_volume_info *vi);
959 /* scan.c */
960 int ubi_compare_lebs(struct ubi_device *ubi, const struct ubi_ainf_peb *aeb,
961 		      int pnum, const struct ubi_vid_hdr *vid_hdr);
962 
963 /* fastmap.c */
964 #ifdef CONFIG_MTD_UBI_FASTMAP
965 size_t ubi_calc_fm_size(struct ubi_device *ubi);
966 int ubi_update_fastmap(struct ubi_device *ubi);
967 int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
968 		     struct ubi_attach_info *scan_ai);
969 #else
970 static inline int ubi_update_fastmap(struct ubi_device *ubi) { return 0; }
971 #endif
972 
973 /* block.c */
974 #ifdef CONFIG_MTD_UBI_BLOCK
975 int ubiblock_init(void);
976 void ubiblock_exit(void);
977 int ubiblock_create(struct ubi_volume_info *vi);
978 int ubiblock_remove(struct ubi_volume_info *vi);
979 #else
980 static inline int ubiblock_init(void) { return 0; }
981 static inline void ubiblock_exit(void) {}
982 static inline int ubiblock_create(struct ubi_volume_info *vi)
983 {
984 	return -ENOSYS;
985 }
986 static inline int ubiblock_remove(struct ubi_volume_info *vi)
987 {
988 	return -ENOSYS;
989 }
990 #endif
991 
992 /*
993  * ubi_for_each_free_peb - walk the UBI free RB tree.
994  * @ubi: UBI device description object
995  * @e: a pointer to a ubi_wl_entry to use as cursor
996  * @pos: a pointer to RB-tree entry type to use as a loop counter
997  */
998 #define ubi_for_each_free_peb(ubi, e, tmp_rb)	\
999 	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->free, u.rb)
1000 
1001 /*
1002  * ubi_for_each_used_peb - walk the UBI used RB tree.
1003  * @ubi: UBI device description object
1004  * @e: a pointer to a ubi_wl_entry to use as cursor
1005  * @pos: a pointer to RB-tree entry type to use as a loop counter
1006  */
1007 #define ubi_for_each_used_peb(ubi, e, tmp_rb)	\
1008 	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->used, u.rb)
1009 
1010 /*
1011  * ubi_for_each_scub_peb - walk the UBI scub RB tree.
1012  * @ubi: UBI device description object
1013  * @e: a pointer to a ubi_wl_entry to use as cursor
1014  * @pos: a pointer to RB-tree entry type to use as a loop counter
1015  */
1016 #define ubi_for_each_scrub_peb(ubi, e, tmp_rb)	\
1017 	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->scrub, u.rb)
1018 
1019 /*
1020  * ubi_for_each_protected_peb - walk the UBI protection queue.
1021  * @ubi: UBI device description object
1022  * @i: a integer used as counter
1023  * @e: a pointer to a ubi_wl_entry to use as cursor
1024  */
1025 #define ubi_for_each_protected_peb(ubi, i, e)	\
1026 	for ((i) = 0; (i) < UBI_PROT_QUEUE_LEN; (i)++)	\
1027 		list_for_each_entry((e), &(ubi->pq[(i)]), u.list)
1028 
1029 /*
1030  * ubi_rb_for_each_entry - walk an RB-tree.
1031  * @rb: a pointer to type 'struct rb_node' to use as a loop counter
1032  * @pos: a pointer to RB-tree entry type to use as a loop counter
1033  * @root: RB-tree's root
1034  * @member: the name of the 'struct rb_node' within the RB-tree entry
1035  */
1036 #define ubi_rb_for_each_entry(rb, pos, root, member)                         \
1037 	for (rb = rb_first(root),                                            \
1038 	     pos = (rb ? container_of(rb, typeof(*pos), member) : NULL);     \
1039 	     rb;                                                             \
1040 	     rb = rb_next(rb),                                               \
1041 	     pos = (rb ? container_of(rb, typeof(*pos), member) : NULL))
1042 
1043 /*
1044  * ubi_move_aeb_to_list - move a PEB from the volume tree to a list.
1045  *
1046  * @av: volume attaching information
1047  * @aeb: attaching eraseblock information
1048  * @list: the list to move to
1049  */
1050 static inline void ubi_move_aeb_to_list(struct ubi_ainf_volume *av,
1051 					 struct ubi_ainf_peb *aeb,
1052 					 struct list_head *list)
1053 {
1054 		rb_erase(&aeb->u.rb, &av->root);
1055 		list_add_tail(&aeb->u.list, list);
1056 }
1057 
1058 /**
1059  * ubi_init_vid_buf - Initialize a VID buffer
1060  * @ubi: the UBI device
1061  * @vidb: the VID buffer to initialize
1062  * @buf: the underlying buffer
1063  */
1064 static inline void ubi_init_vid_buf(const struct ubi_device *ubi,
1065 				    struct ubi_vid_io_buf *vidb,
1066 				    void *buf)
1067 {
1068 	if (buf)
1069 		memset(buf, 0, ubi->vid_hdr_alsize);
1070 
1071 	vidb->buffer = buf;
1072 	vidb->hdr = buf + ubi->vid_hdr_shift;
1073 }
1074 
1075 /**
1076  * ubi_init_vid_buf - Allocate a VID buffer
1077  * @ubi: the UBI device
1078  * @gfp_flags: GFP flags to use for the allocation
1079  */
1080 static inline struct ubi_vid_io_buf *
1081 ubi_alloc_vid_buf(const struct ubi_device *ubi, gfp_t gfp_flags)
1082 {
1083 	struct ubi_vid_io_buf *vidb;
1084 	void *buf;
1085 
1086 	vidb = kzalloc(sizeof(*vidb), gfp_flags);
1087 	if (!vidb)
1088 		return NULL;
1089 
1090 	buf = kmalloc(ubi->vid_hdr_alsize, gfp_flags);
1091 	if (!buf) {
1092 		kfree(vidb);
1093 		return NULL;
1094 	}
1095 
1096 	ubi_init_vid_buf(ubi, vidb, buf);
1097 
1098 	return vidb;
1099 }
1100 
1101 /**
1102  * ubi_free_vid_buf - Free a VID buffer
1103  * @vidb: the VID buffer to free
1104  */
1105 static inline void ubi_free_vid_buf(struct ubi_vid_io_buf *vidb)
1106 {
1107 	if (!vidb)
1108 		return;
1109 
1110 	kfree(vidb->buffer);
1111 	kfree(vidb);
1112 }
1113 
1114 /**
1115  * ubi_get_vid_hdr - Get the VID header attached to a VID buffer
1116  * @vidb: VID buffer
1117  */
1118 static inline struct ubi_vid_hdr *ubi_get_vid_hdr(struct ubi_vid_io_buf *vidb)
1119 {
1120 	return vidb->hdr;
1121 }
1122 
1123 /*
1124  * This function is equivalent to 'ubi_io_read()', but @offset is relative to
1125  * the beginning of the logical eraseblock, not to the beginning of the
1126  * physical eraseblock.
1127  */
1128 static inline int ubi_io_read_data(const struct ubi_device *ubi, void *buf,
1129 				   int pnum, int offset, int len)
1130 {
1131 	ubi_assert(offset >= 0);
1132 	return ubi_io_read(ubi, buf, pnum, offset + ubi->leb_start, len);
1133 }
1134 
1135 /*
1136  * This function is equivalent to 'ubi_io_write()', but @offset is relative to
1137  * the beginning of the logical eraseblock, not to the beginning of the
1138  * physical eraseblock.
1139  */
1140 static inline int ubi_io_write_data(struct ubi_device *ubi, const void *buf,
1141 				    int pnum, int offset, int len)
1142 {
1143 	ubi_assert(offset >= 0);
1144 	return ubi_io_write(ubi, buf, pnum, offset + ubi->leb_start, len);
1145 }
1146 
1147 /**
1148  * ubi_ro_mode - switch to read-only mode.
1149  * @ubi: UBI device description object
1150  */
1151 static inline void ubi_ro_mode(struct ubi_device *ubi)
1152 {
1153 	if (!ubi->ro_mode) {
1154 		ubi->ro_mode = 1;
1155 		ubi_warn(ubi, "switch to read-only mode");
1156 		dump_stack();
1157 	}
1158 }
1159 
1160 /**
1161  * vol_id2idx - get table index by volume ID.
1162  * @ubi: UBI device description object
1163  * @vol_id: volume ID
1164  */
1165 static inline int vol_id2idx(const struct ubi_device *ubi, int vol_id)
1166 {
1167 	if (vol_id >= UBI_INTERNAL_VOL_START)
1168 		return vol_id - UBI_INTERNAL_VOL_START + ubi->vtbl_slots;
1169 	else
1170 		return vol_id;
1171 }
1172 
1173 /**
1174  * idx2vol_id - get volume ID by table index.
1175  * @ubi: UBI device description object
1176  * @idx: table index
1177  */
1178 static inline int idx2vol_id(const struct ubi_device *ubi, int idx)
1179 {
1180 	if (idx >= ubi->vtbl_slots)
1181 		return idx - ubi->vtbl_slots + UBI_INTERNAL_VOL_START;
1182 	else
1183 		return idx;
1184 }
1185 
1186 /**
1187  * ubi_is_fm_vol - check whether a volume ID is a Fastmap volume.
1188  * @vol_id: volume ID
1189  */
1190 static inline bool ubi_is_fm_vol(int vol_id)
1191 {
1192 	switch (vol_id) {
1193 		case UBI_FM_SB_VOLUME_ID:
1194 		case UBI_FM_DATA_VOLUME_ID:
1195 		return true;
1196 	}
1197 
1198 	return false;
1199 }
1200 
1201 /**
1202  * ubi_find_fm_block - check whether a PEB is part of the current Fastmap.
1203  * @ubi: UBI device description object
1204  * @pnum: physical eraseblock to look for
1205  *
1206  * This function returns a wear leveling object if @pnum relates to the current
1207  * fastmap, @NULL otherwise.
1208  */
1209 static inline struct ubi_wl_entry *ubi_find_fm_block(const struct ubi_device *ubi,
1210 						     int pnum)
1211 {
1212 	int i;
1213 
1214 	if (ubi->fm) {
1215 		for (i = 0; i < ubi->fm->used_blocks; i++) {
1216 			if (ubi->fm->e[i]->pnum == pnum)
1217 				return ubi->fm->e[i];
1218 		}
1219 	}
1220 
1221 	return NULL;
1222 }
1223 
1224 #endif /* !__UBI_UBI_H__ */
1225