xref: /openbmc/linux/drivers/mtd/ubi/ubi.h (revision e2c75e76)
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 bad physical eraseblocks or not
548  * @nor_flash: non-zero if working on top of NOR flash
549  * @max_write_size: maximum amount of bytes the underlying flash can write at a
550  *                  time (MTD write buffer size)
551  * @mtd: MTD device descriptor
552  *
553  * @peb_buf: a buffer of PEB size used for different purposes
554  * @buf_mutex: protects @peb_buf
555  * @ckvol_mutex: serializes static volume checking when opening
556  *
557  * @dbg: debugging information for this UBI device
558  */
559 struct ubi_device {
560 	struct cdev cdev;
561 	struct device dev;
562 	int ubi_num;
563 	char ubi_name[sizeof(UBI_NAME_STR)+5];
564 	int vol_count;
565 	struct ubi_volume *volumes[UBI_MAX_VOLUMES+UBI_INT_VOL_COUNT];
566 	spinlock_t volumes_lock;
567 	int ref_count;
568 	int image_seq;
569 
570 	int rsvd_pebs;
571 	int avail_pebs;
572 	int beb_rsvd_pebs;
573 	int beb_rsvd_level;
574 	int bad_peb_limit;
575 
576 	int autoresize_vol_id;
577 	int vtbl_slots;
578 	int vtbl_size;
579 	struct ubi_vtbl_record *vtbl;
580 	struct mutex device_mutex;
581 
582 	int max_ec;
583 	/* Note, mean_ec is not updated run-time - should be fixed */
584 	int mean_ec;
585 
586 	/* EBA sub-system's stuff */
587 	unsigned long long global_sqnum;
588 	spinlock_t ltree_lock;
589 	struct rb_root ltree;
590 	struct mutex alc_mutex;
591 
592 	/* Fastmap stuff */
593 	int fm_disabled;
594 	struct ubi_fastmap_layout *fm;
595 	struct ubi_fm_pool fm_pool;
596 	struct ubi_fm_pool fm_wl_pool;
597 	struct rw_semaphore fm_eba_sem;
598 	struct rw_semaphore fm_protect;
599 	void *fm_buf;
600 	size_t fm_size;
601 	struct work_struct fm_work;
602 	int fm_work_scheduled;
603 	int fast_attach;
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  */
675 struct 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  */
710 struct 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  */
759 struct 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  * @anchor: produce a anchor PEB to by used by fastmap
795  *
796  * The @func pointer points to the worker function. If the @shutdown argument is
797  * not zero, the worker has to free the resources and exit immediately as the
798  * WL sub-system is shutting down.
799  * The worker has to return zero in case of success and a negative error code in
800  * case of failure.
801  */
802 struct ubi_work {
803 	struct list_head list;
804 	int (*func)(struct ubi_device *ubi, struct ubi_work *wrk, int shutdown);
805 	/* The below fields are only relevant to erasure works */
806 	struct ubi_wl_entry *e;
807 	int vol_id;
808 	int lnum;
809 	int torture;
810 	int anchor;
811 };
812 
813 #include "debug.h"
814 
815 extern struct kmem_cache *ubi_wl_entry_slab;
816 extern const struct file_operations ubi_ctrl_cdev_operations;
817 extern const struct file_operations ubi_cdev_operations;
818 extern const struct file_operations ubi_vol_cdev_operations;
819 extern struct class ubi_class;
820 extern struct mutex ubi_devices_mutex;
821 extern struct blocking_notifier_head ubi_notifiers;
822 
823 /* attach.c */
824 struct ubi_ainf_peb *ubi_alloc_aeb(struct ubi_attach_info *ai, int pnum,
825 				   int ec);
826 void ubi_free_aeb(struct ubi_attach_info *ai, struct ubi_ainf_peb *aeb);
827 int ubi_add_to_av(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum,
828 		  int ec, const struct ubi_vid_hdr *vid_hdr, int bitflips);
829 struct ubi_ainf_volume *ubi_add_av(struct ubi_attach_info *ai, int vol_id);
830 struct ubi_ainf_volume *ubi_find_av(const struct ubi_attach_info *ai,
831 				    int vol_id);
832 void ubi_remove_av(struct ubi_attach_info *ai, struct ubi_ainf_volume *av);
833 struct ubi_ainf_peb *ubi_early_get_peb(struct ubi_device *ubi,
834 				       struct ubi_attach_info *ai);
835 int ubi_attach(struct ubi_device *ubi, int force_scan);
836 void ubi_destroy_ai(struct ubi_attach_info *ai);
837 
838 /* vtbl.c */
839 int ubi_change_vtbl_record(struct ubi_device *ubi, int idx,
840 			   struct ubi_vtbl_record *vtbl_rec);
841 int ubi_vtbl_rename_volumes(struct ubi_device *ubi,
842 			    struct list_head *rename_list);
843 int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_attach_info *ai);
844 
845 /* vmt.c */
846 int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req);
847 int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl);
848 int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs);
849 int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list);
850 int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol);
851 void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol);
852 
853 /* upd.c */
854 int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol,
855 		     long long bytes);
856 int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol,
857 			 const void __user *buf, int count);
858 int ubi_start_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
859 			 const struct ubi_leb_change_req *req);
860 int ubi_more_leb_change_data(struct ubi_device *ubi, struct ubi_volume *vol,
861 			     const void __user *buf, int count);
862 
863 /* misc.c */
864 int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf,
865 		      int length);
866 int ubi_check_volume(struct ubi_device *ubi, int vol_id);
867 void ubi_update_reserved(struct ubi_device *ubi);
868 void ubi_calculate_reserved(struct ubi_device *ubi);
869 int ubi_check_pattern(const void *buf, uint8_t patt, int size);
870 
871 static inline bool ubi_leb_valid(struct ubi_volume *vol, int lnum)
872 {
873 	return lnum >= 0 && lnum < vol->reserved_pebs;
874 }
875 
876 /* eba.c */
877 struct ubi_eba_table *ubi_eba_create_table(struct ubi_volume *vol,
878 					   int nentries);
879 void ubi_eba_destroy_table(struct ubi_eba_table *tbl);
880 void ubi_eba_copy_table(struct ubi_volume *vol, struct ubi_eba_table *dst,
881 			int nentries);
882 void ubi_eba_replace_table(struct ubi_volume *vol, struct ubi_eba_table *tbl);
883 void ubi_eba_get_ldesc(struct ubi_volume *vol, int lnum,
884 		       struct ubi_eba_leb_desc *ldesc);
885 bool ubi_eba_is_mapped(struct ubi_volume *vol, int lnum);
886 int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol,
887 		      int lnum);
888 int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
889 		     void *buf, int offset, int len, int check);
890 int ubi_eba_read_leb_sg(struct ubi_device *ubi, struct ubi_volume *vol,
891 			struct ubi_sgl *sgl, int lnum, int offset, int len,
892 			int check);
893 int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
894 		      const void *buf, int offset, int len);
895 int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol,
896 			 int lnum, const void *buf, int len, int used_ebs);
897 int ubi_eba_atomic_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
898 			      int lnum, const void *buf, int len);
899 int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
900 		     struct ubi_vid_io_buf *vidb);
901 int ubi_eba_init(struct ubi_device *ubi, struct ubi_attach_info *ai);
902 unsigned long long ubi_next_sqnum(struct ubi_device *ubi);
903 int self_check_eba(struct ubi_device *ubi, struct ubi_attach_info *ai_fastmap,
904 		   struct ubi_attach_info *ai_scan);
905 
906 /* wl.c */
907 int ubi_wl_get_peb(struct ubi_device *ubi);
908 int ubi_wl_put_peb(struct ubi_device *ubi, int vol_id, int lnum,
909 		   int pnum, int torture);
910 int ubi_wl_flush(struct ubi_device *ubi, int vol_id, int lnum);
911 int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum);
912 int ubi_wl_init(struct ubi_device *ubi, struct ubi_attach_info *ai);
913 void ubi_wl_close(struct ubi_device *ubi);
914 int ubi_thread(void *u);
915 struct ubi_wl_entry *ubi_wl_get_fm_peb(struct ubi_device *ubi, int anchor);
916 int ubi_wl_put_fm_peb(struct ubi_device *ubi, struct ubi_wl_entry *used_e,
917 		      int lnum, int torture);
918 int ubi_is_erase_work(struct ubi_work *wrk);
919 void ubi_refill_pools(struct ubi_device *ubi);
920 int ubi_ensure_anchor_pebs(struct ubi_device *ubi);
921 
922 /* io.c */
923 int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset,
924 		int len);
925 int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
926 		 int len);
927 int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture);
928 int ubi_io_is_bad(const struct ubi_device *ubi, int pnum);
929 int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum);
930 int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum,
931 		       struct ubi_ec_hdr *ec_hdr, int verbose);
932 int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum,
933 			struct ubi_ec_hdr *ec_hdr);
934 int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum,
935 			struct ubi_vid_io_buf *vidb, int verbose);
936 int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum,
937 			 struct ubi_vid_io_buf *vidb);
938 
939 /* build.c */
940 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
941 		       int vid_hdr_offset, int max_beb_per1024);
942 int ubi_detach_mtd_dev(int ubi_num, int anyway);
943 struct ubi_device *ubi_get_device(int ubi_num);
944 void ubi_put_device(struct ubi_device *ubi);
945 struct ubi_device *ubi_get_by_major(int major);
946 int ubi_major2num(int major);
947 int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol,
948 		      int ntype);
949 int ubi_notify_all(struct ubi_device *ubi, int ntype,
950 		   struct notifier_block *nb);
951 int ubi_enumerate_volumes(struct notifier_block *nb);
952 void ubi_free_internal_volumes(struct ubi_device *ubi);
953 
954 /* kapi.c */
955 void ubi_do_get_device_info(struct ubi_device *ubi, struct ubi_device_info *di);
956 void ubi_do_get_volume_info(struct ubi_device *ubi, struct ubi_volume *vol,
957 			    struct ubi_volume_info *vi);
958 /* scan.c */
959 int ubi_compare_lebs(struct ubi_device *ubi, const struct ubi_ainf_peb *aeb,
960 		      int pnum, const struct ubi_vid_hdr *vid_hdr);
961 
962 /* fastmap.c */
963 #ifdef CONFIG_MTD_UBI_FASTMAP
964 size_t ubi_calc_fm_size(struct ubi_device *ubi);
965 int ubi_update_fastmap(struct ubi_device *ubi);
966 int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
967 		     struct ubi_attach_info *scan_ai);
968 #else
969 static inline int ubi_update_fastmap(struct ubi_device *ubi) { return 0; }
970 #endif
971 
972 /* block.c */
973 #ifdef CONFIG_MTD_UBI_BLOCK
974 int ubiblock_init(void);
975 void ubiblock_exit(void);
976 int ubiblock_create(struct ubi_volume_info *vi);
977 int ubiblock_remove(struct ubi_volume_info *vi);
978 #else
979 static inline int ubiblock_init(void) { return 0; }
980 static inline void ubiblock_exit(void) {}
981 static inline int ubiblock_create(struct ubi_volume_info *vi)
982 {
983 	return -ENOSYS;
984 }
985 static inline int ubiblock_remove(struct ubi_volume_info *vi)
986 {
987 	return -ENOSYS;
988 }
989 #endif
990 
991 /*
992  * ubi_for_each_free_peb - walk the UBI free RB tree.
993  * @ubi: UBI device description object
994  * @e: a pointer to a ubi_wl_entry to use as cursor
995  * @pos: a pointer to RB-tree entry type to use as a loop counter
996  */
997 #define ubi_for_each_free_peb(ubi, e, tmp_rb)	\
998 	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->free, u.rb)
999 
1000 /*
1001  * ubi_for_each_used_peb - walk the UBI used RB tree.
1002  * @ubi: UBI device description object
1003  * @e: a pointer to a ubi_wl_entry to use as cursor
1004  * @pos: a pointer to RB-tree entry type to use as a loop counter
1005  */
1006 #define ubi_for_each_used_peb(ubi, e, tmp_rb)	\
1007 	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->used, u.rb)
1008 
1009 /*
1010  * ubi_for_each_scub_peb - walk the UBI scub RB tree.
1011  * @ubi: UBI device description object
1012  * @e: a pointer to a ubi_wl_entry to use as cursor
1013  * @pos: a pointer to RB-tree entry type to use as a loop counter
1014  */
1015 #define ubi_for_each_scrub_peb(ubi, e, tmp_rb)	\
1016 	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->scrub, u.rb)
1017 
1018 /*
1019  * ubi_for_each_protected_peb - walk the UBI protection queue.
1020  * @ubi: UBI device description object
1021  * @i: a integer used as counter
1022  * @e: a pointer to a ubi_wl_entry to use as cursor
1023  */
1024 #define ubi_for_each_protected_peb(ubi, i, e)	\
1025 	for ((i) = 0; (i) < UBI_PROT_QUEUE_LEN; (i)++)	\
1026 		list_for_each_entry((e), &(ubi->pq[(i)]), u.list)
1027 
1028 /*
1029  * ubi_rb_for_each_entry - walk an RB-tree.
1030  * @rb: a pointer to type 'struct rb_node' to use as a loop counter
1031  * @pos: a pointer to RB-tree entry type to use as a loop counter
1032  * @root: RB-tree's root
1033  * @member: the name of the 'struct rb_node' within the RB-tree entry
1034  */
1035 #define ubi_rb_for_each_entry(rb, pos, root, member)                         \
1036 	for (rb = rb_first(root),                                            \
1037 	     pos = (rb ? container_of(rb, typeof(*pos), member) : NULL);     \
1038 	     rb;                                                             \
1039 	     rb = rb_next(rb),                                               \
1040 	     pos = (rb ? container_of(rb, typeof(*pos), member) : NULL))
1041 
1042 /*
1043  * ubi_move_aeb_to_list - move a PEB from the volume tree to a list.
1044  *
1045  * @av: volume attaching information
1046  * @aeb: attaching eraseblock information
1047  * @list: the list to move to
1048  */
1049 static inline void ubi_move_aeb_to_list(struct ubi_ainf_volume *av,
1050 					 struct ubi_ainf_peb *aeb,
1051 					 struct list_head *list)
1052 {
1053 		rb_erase(&aeb->u.rb, &av->root);
1054 		list_add_tail(&aeb->u.list, list);
1055 }
1056 
1057 /**
1058  * ubi_init_vid_buf - Initialize a VID buffer
1059  * @ubi: the UBI device
1060  * @vidb: the VID buffer to initialize
1061  * @buf: the underlying buffer
1062  */
1063 static inline void ubi_init_vid_buf(const struct ubi_device *ubi,
1064 				    struct ubi_vid_io_buf *vidb,
1065 				    void *buf)
1066 {
1067 	if (buf)
1068 		memset(buf, 0, ubi->vid_hdr_alsize);
1069 
1070 	vidb->buffer = buf;
1071 	vidb->hdr = buf + ubi->vid_hdr_shift;
1072 }
1073 
1074 /**
1075  * ubi_init_vid_buf - Allocate a VID buffer
1076  * @ubi: the UBI device
1077  * @gfp_flags: GFP flags to use for the allocation
1078  */
1079 static inline struct ubi_vid_io_buf *
1080 ubi_alloc_vid_buf(const struct ubi_device *ubi, gfp_t gfp_flags)
1081 {
1082 	struct ubi_vid_io_buf *vidb;
1083 	void *buf;
1084 
1085 	vidb = kzalloc(sizeof(*vidb), gfp_flags);
1086 	if (!vidb)
1087 		return NULL;
1088 
1089 	buf = kmalloc(ubi->vid_hdr_alsize, gfp_flags);
1090 	if (!buf) {
1091 		kfree(vidb);
1092 		return NULL;
1093 	}
1094 
1095 	ubi_init_vid_buf(ubi, vidb, buf);
1096 
1097 	return vidb;
1098 }
1099 
1100 /**
1101  * ubi_free_vid_buf - Free a VID buffer
1102  * @vidb: the VID buffer to free
1103  */
1104 static inline void ubi_free_vid_buf(struct ubi_vid_io_buf *vidb)
1105 {
1106 	if (!vidb)
1107 		return;
1108 
1109 	kfree(vidb->buffer);
1110 	kfree(vidb);
1111 }
1112 
1113 /**
1114  * ubi_get_vid_hdr - Get the VID header attached to a VID buffer
1115  * @vidb: VID buffer
1116  */
1117 static inline struct ubi_vid_hdr *ubi_get_vid_hdr(struct ubi_vid_io_buf *vidb)
1118 {
1119 	return vidb->hdr;
1120 }
1121 
1122 /*
1123  * This function is equivalent to 'ubi_io_read()', but @offset is relative to
1124  * the beginning of the logical eraseblock, not to the beginning of the
1125  * physical eraseblock.
1126  */
1127 static inline int ubi_io_read_data(const struct ubi_device *ubi, void *buf,
1128 				   int pnum, int offset, int len)
1129 {
1130 	ubi_assert(offset >= 0);
1131 	return ubi_io_read(ubi, buf, pnum, offset + ubi->leb_start, len);
1132 }
1133 
1134 /*
1135  * This function is equivalent to 'ubi_io_write()', but @offset is relative to
1136  * the beginning of the logical eraseblock, not to the beginning of the
1137  * physical eraseblock.
1138  */
1139 static inline int ubi_io_write_data(struct ubi_device *ubi, const void *buf,
1140 				    int pnum, int offset, int len)
1141 {
1142 	ubi_assert(offset >= 0);
1143 	return ubi_io_write(ubi, buf, pnum, offset + ubi->leb_start, len);
1144 }
1145 
1146 /**
1147  * ubi_ro_mode - switch to read-only mode.
1148  * @ubi: UBI device description object
1149  */
1150 static inline void ubi_ro_mode(struct ubi_device *ubi)
1151 {
1152 	if (!ubi->ro_mode) {
1153 		ubi->ro_mode = 1;
1154 		ubi_warn(ubi, "switch to read-only mode");
1155 		dump_stack();
1156 	}
1157 }
1158 
1159 /**
1160  * vol_id2idx - get table index by volume ID.
1161  * @ubi: UBI device description object
1162  * @vol_id: volume ID
1163  */
1164 static inline int vol_id2idx(const struct ubi_device *ubi, int vol_id)
1165 {
1166 	if (vol_id >= UBI_INTERNAL_VOL_START)
1167 		return vol_id - UBI_INTERNAL_VOL_START + ubi->vtbl_slots;
1168 	else
1169 		return vol_id;
1170 }
1171 
1172 /**
1173  * idx2vol_id - get volume ID by table index.
1174  * @ubi: UBI device description object
1175  * @idx: table index
1176  */
1177 static inline int idx2vol_id(const struct ubi_device *ubi, int idx)
1178 {
1179 	if (idx >= ubi->vtbl_slots)
1180 		return idx - ubi->vtbl_slots + UBI_INTERNAL_VOL_START;
1181 	else
1182 		return idx;
1183 }
1184 
1185 /**
1186  * ubi_is_fm_vol - check whether a volume ID is a Fastmap volume.
1187  * @vol_id: volume ID
1188  */
1189 static inline bool ubi_is_fm_vol(int vol_id)
1190 {
1191 	switch (vol_id) {
1192 		case UBI_FM_SB_VOLUME_ID:
1193 		case UBI_FM_DATA_VOLUME_ID:
1194 		return true;
1195 	}
1196 
1197 	return false;
1198 }
1199 
1200 /**
1201  * ubi_find_fm_block - check whether a PEB is part of the current Fastmap.
1202  * @ubi: UBI device description object
1203  * @pnum: physical eraseblock to look for
1204  *
1205  * This function returns a wear leveling object if @pnum relates to the current
1206  * fastmap, @NULL otherwise.
1207  */
1208 static inline struct ubi_wl_entry *ubi_find_fm_block(const struct ubi_device *ubi,
1209 						     int pnum)
1210 {
1211 	int i;
1212 
1213 	if (ubi->fm) {
1214 		for (i = 0; i < ubi->fm->used_blocks; i++) {
1215 			if (ubi->fm->e[i]->pnum == pnum)
1216 				return ubi->fm->e[i];
1217 		}
1218 	}
1219 
1220 	return NULL;
1221 }
1222 
1223 #endif /* !__UBI_UBI_H__ */
1224