xref: /linux/drivers/mtd/ubi/ubi.h (revision be239684b18e1cdcafcf8c7face4a2f562c745ad)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Copyright (c) International Business Machines Corp., 2006
4  * Copyright (c) Nokia Corporation, 2006, 2007
5  *
6  * Author: Artem Bityutskiy (Битюцкий Артём)
7  */
8 
9 #ifndef __UBI_UBI_H__
10 #define __UBI_UBI_H__
11 
12 #include <linux/types.h>
13 #include <linux/list.h>
14 #include <linux/rbtree.h>
15 #include <linux/sched.h>
16 #include <linux/wait.h>
17 #include <linux/mutex.h>
18 #include <linux/rwsem.h>
19 #include <linux/spinlock.h>
20 #include <linux/fs.h>
21 #include <linux/cdev.h>
22 #include <linux/device.h>
23 #include <linux/slab.h>
24 #include <linux/string.h>
25 #include <linux/vmalloc.h>
26 #include <linux/notifier.h>
27 #include <linux/mtd/mtd.h>
28 #include <linux/mtd/ubi.h>
29 #include <linux/pgtable.h>
30 
31 #include "ubi-media.h"
32 
33 /* Maximum number of supported UBI devices */
34 #define UBI_MAX_DEVICES 32
35 
36 /* UBI name used for character devices, sysfs, etc */
37 #define UBI_NAME_STR "ubi"
38 
39 struct ubi_device;
40 
41 /* Normal UBI messages */
42 __printf(2, 3)
43 void ubi_msg(const struct ubi_device *ubi, const char *fmt, ...);
44 
45 /* UBI warning messages */
46 __printf(2, 3)
47 void ubi_warn(const struct ubi_device *ubi, const char *fmt, ...);
48 
49 /* UBI error messages */
50 __printf(2, 3)
51 void ubi_err(const struct ubi_device *ubi, const char *fmt, ...);
52 
53 /* Background thread name pattern */
54 #define UBI_BGT_NAME_PATTERN "ubi_bgt%dd"
55 
56 /*
57  * This marker in the EBA table means that the LEB is um-mapped.
58  * NOTE! It has to have the same value as %UBI_ALL.
59  */
60 #define UBI_LEB_UNMAPPED -1
61 
62 /*
63  * In case of errors, UBI tries to repeat the operation several times before
64  * returning error. The below constant defines how many times UBI re-tries.
65  */
66 #define UBI_IO_RETRIES 3
67 
68 /*
69  * Length of the protection queue. The length is effectively equivalent to the
70  * number of (global) erase cycles PEBs are protected from the wear-leveling
71  * worker.
72  */
73 #define UBI_PROT_QUEUE_LEN 10
74 
75 /* The volume ID/LEB number/erase counter is unknown */
76 #define UBI_UNKNOWN -1
77 
78 /*
79  * The UBI debugfs directory name pattern and maximum name length (3 for "ubi"
80  * + 2 for the number plus 1 for the trailing zero byte.
81  */
82 #define UBI_DFS_DIR_NAME "ubi%d"
83 #define UBI_DFS_DIR_LEN  (3 + 2 + 1)
84 
85 /* Number of physical eraseblocks reserved for atomic LEB change operation */
86 #define EBA_RESERVED_PEBS 1
87 
88 /*
89  * Error codes returned by the I/O sub-system.
90  *
91  * UBI_IO_FF: the read region of flash contains only 0xFFs
92  * UBI_IO_FF_BITFLIPS: the same as %UBI_IO_FF, but also there was a data
93  *                     integrity error reported by the MTD driver
94  *                     (uncorrectable ECC error in case of NAND)
95  * UBI_IO_BAD_HDR: the EC or VID header is corrupted (bad magic or CRC)
96  * UBI_IO_BAD_HDR_EBADMSG: the same as %UBI_IO_BAD_HDR, but also there was a
97  *                         data integrity error reported by the MTD driver
98  *                         (uncorrectable ECC error in case of NAND)
99  * UBI_IO_BITFLIPS: bit-flips were detected and corrected
100  *
101  * Note, it is probably better to have bit-flip and ebadmsg as flags which can
102  * be or'ed with other error code. But this is a big change because there are
103  * may callers, so it does not worth the risk of introducing a bug
104  */
105 enum {
106 	UBI_IO_FF = 1,
107 	UBI_IO_FF_BITFLIPS,
108 	UBI_IO_BAD_HDR,
109 	UBI_IO_BAD_HDR_EBADMSG,
110 	UBI_IO_BITFLIPS,
111 };
112 
113 /*
114  * Return codes of the 'ubi_eba_copy_leb()' function.
115  *
116  * MOVE_CANCEL_RACE: canceled because the volume is being deleted, the source
117  *                   PEB was put meanwhile, or there is I/O on the source PEB
118  * MOVE_SOURCE_RD_ERR: canceled because there was a read error from the source
119  *                     PEB
120  * MOVE_TARGET_RD_ERR: canceled because there was a read error from the target
121  *                     PEB
122  * MOVE_TARGET_WR_ERR: canceled because there was a write error to the target
123  *                     PEB
124  * MOVE_TARGET_BITFLIPS: canceled because a bit-flip was detected in the
125  *                       target PEB
126  * MOVE_RETRY: retry scrubbing the PEB
127  */
128 enum {
129 	MOVE_CANCEL_RACE = 1,
130 	MOVE_SOURCE_RD_ERR,
131 	MOVE_TARGET_RD_ERR,
132 	MOVE_TARGET_WR_ERR,
133 	MOVE_TARGET_BITFLIPS,
134 	MOVE_RETRY,
135 };
136 
137 /*
138  * Return codes of the fastmap sub-system
139  *
140  * UBI_NO_FASTMAP: No fastmap super block was found
141  * UBI_BAD_FASTMAP: A fastmap was found but it's unusable
142  */
143 enum {
144 	UBI_NO_FASTMAP = 1,
145 	UBI_BAD_FASTMAP,
146 };
147 
148 /**
149  * struct ubi_vid_io_buf - VID buffer used to read/write VID info to/from the
150  *			   flash.
151  * @hdr: a pointer to the VID header stored in buffer
152  * @buffer: underlying buffer
153  */
154 struct ubi_vid_io_buf {
155 	struct ubi_vid_hdr *hdr;
156 	void *buffer;
157 };
158 
159 /**
160  * struct ubi_wl_entry - wear-leveling entry.
161  * @u.rb: link in the corresponding (free/used) RB-tree
162  * @u.list: link in the protection queue
163  * @ec: erase counter
164  * @pnum: physical eraseblock number
165  *
166  * This data structure is used in the WL sub-system. Each physical eraseblock
167  * has a corresponding &struct wl_entry object which may be kept in different
168  * RB-trees. See WL sub-system for details.
169  */
170 struct ubi_wl_entry {
171 	union {
172 		struct rb_node rb;
173 		struct list_head list;
174 	} u;
175 	int ec;
176 	int pnum;
177 };
178 
179 /**
180  * struct ubi_ltree_entry - an entry in the lock tree.
181  * @rb: links RB-tree nodes
182  * @vol_id: volume ID of the locked logical eraseblock
183  * @lnum: locked logical eraseblock number
184  * @users: how many tasks are using this logical eraseblock or wait for it
185  * @mutex: read/write mutex to implement read/write access serialization to
186  *         the (@vol_id, @lnum) logical eraseblock
187  *
188  * This data structure is used in the EBA sub-system to implement per-LEB
189  * locking. When a logical eraseblock is being locked - corresponding
190  * &struct ubi_ltree_entry object is inserted to the lock tree (@ubi->ltree).
191  * See EBA sub-system for details.
192  */
193 struct ubi_ltree_entry {
194 	struct rb_node rb;
195 	int vol_id;
196 	int lnum;
197 	int users;
198 	struct rw_semaphore mutex;
199 };
200 
201 /**
202  * struct ubi_rename_entry - volume re-name description data structure.
203  * @new_name_len: new volume name length
204  * @new_name: new volume name
205  * @remove: if not zero, this volume should be removed, not re-named
206  * @desc: descriptor of the volume
207  * @list: links re-name entries into a list
208  *
209  * This data structure is utilized in the multiple volume re-name code. Namely,
210  * UBI first creates a list of &struct ubi_rename_entry objects from the
211  * &struct ubi_rnvol_req request object, and then utilizes this list to do all
212  * the job.
213  */
214 struct ubi_rename_entry {
215 	int new_name_len;
216 	char new_name[UBI_VOL_NAME_MAX + 1];
217 	int remove;
218 	struct ubi_volume_desc *desc;
219 	struct list_head list;
220 };
221 
222 struct ubi_volume_desc;
223 
224 /**
225  * struct ubi_fastmap_layout - in-memory fastmap data structure.
226  * @e: PEBs used by the current fastmap
227  * @to_be_tortured: if non-zero tortured this PEB
228  * @used_blocks: number of used PEBs
229  * @max_pool_size: maximal size of the user pool
230  * @max_wl_pool_size: maximal size of the pool used by the WL sub-system
231  */
232 struct ubi_fastmap_layout {
233 	struct ubi_wl_entry *e[UBI_FM_MAX_BLOCKS];
234 	int to_be_tortured[UBI_FM_MAX_BLOCKS];
235 	int used_blocks;
236 	int max_pool_size;
237 	int max_wl_pool_size;
238 };
239 
240 /**
241  * struct ubi_fm_pool - in-memory fastmap pool
242  * @pebs: PEBs in this pool
243  * @used: number of used PEBs
244  * @size: total number of PEBs in this pool
245  * @max_size: maximal size of the pool
246  *
247  * A pool gets filled with up to max_size.
248  * If all PEBs within the pool are used a new fastmap will be written
249  * to the flash and the pool gets refilled with empty PEBs.
250  *
251  */
252 struct ubi_fm_pool {
253 	int pebs[UBI_FM_MAX_POOL_SIZE];
254 	int used;
255 	int size;
256 	int max_size;
257 };
258 
259 /**
260  * struct ubi_eba_leb_desc - EBA logical eraseblock descriptor
261  * @lnum: the logical eraseblock number
262  * @pnum: the physical eraseblock where the LEB can be found
263  *
264  * This structure is here to hide EBA's internal from other part of the
265  * UBI implementation.
266  *
267  * One can query the position of a LEB by calling ubi_eba_get_ldesc().
268  */
269 struct ubi_eba_leb_desc {
270 	int lnum;
271 	int pnum;
272 };
273 
274 /**
275  * struct ubi_volume - UBI volume description data structure.
276  * @dev: device object to make use of the Linux device model
277  * @cdev: character device object to create character device
278  * @ubi: reference to the UBI device description object
279  * @vol_id: volume ID
280  * @ref_count: volume reference count
281  * @readers: number of users holding this volume in read-only mode
282  * @writers: number of users holding this volume in read-write mode
283  * @exclusive: whether somebody holds this volume in exclusive mode
284  * @metaonly: whether somebody is altering only meta data of this volume
285  *
286  * @reserved_pebs: how many physical eraseblocks are reserved for this volume
287  * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
288  * @usable_leb_size: logical eraseblock size without padding
289  * @used_ebs: how many logical eraseblocks in this volume contain data
290  * @last_eb_bytes: how many bytes are stored in the last logical eraseblock
291  * @used_bytes: how many bytes of data this volume contains
292  * @alignment: volume alignment
293  * @data_pad: how many bytes are not used at the end of physical eraseblocks to
294  *            satisfy the requested alignment
295  * @name_len: volume name length
296  * @name: volume name
297  *
298  * @upd_ebs: how many eraseblocks are expected to be updated
299  * @ch_lnum: LEB number which is being changing by the atomic LEB change
300  *           operation
301  * @upd_bytes: how many bytes are expected to be received for volume update or
302  *             atomic LEB change
303  * @upd_received: how many bytes were already received for volume update or
304  *                atomic LEB change
305  * @upd_buf: update buffer which is used to collect update data or data for
306  *           atomic LEB change
307  *
308  * @eba_tbl: EBA table of this volume (LEB->PEB mapping)
309  * @skip_check: %1 if CRC check of this static volume should be skipped.
310  *		Directly reflects the presence of the
311  *		%UBI_VTBL_SKIP_CRC_CHECK_FLG flag in the vtbl entry
312  * @checked: %1 if this static volume was checked
313  * @corrupted: %1 if the volume is corrupted (static volumes only)
314  * @upd_marker: %1 if the update marker is set for this volume
315  * @updating: %1 if the volume is being updated
316  * @changing_leb: %1 if the atomic LEB change ioctl command is in progress
317  * @direct_writes: %1 if direct writes are enabled for this volume
318  *
319  * @checkmap: bitmap to remember which PEB->LEB mappings got checked,
320  *            protected by UBI LEB lock tree.
321  *
322  * The @corrupted field indicates that the volume's contents is corrupted.
323  * Since UBI protects only static volumes, this field is not relevant to
324  * dynamic volumes - it is user's responsibility to assure their data
325  * integrity.
326  *
327  * The @upd_marker flag indicates that this volume is either being updated at
328  * the moment or is damaged because of an unclean reboot.
329  */
330 struct ubi_volume {
331 	struct device dev;
332 	struct cdev cdev;
333 	struct ubi_device *ubi;
334 	int vol_id;
335 	int ref_count;
336 	int readers;
337 	int writers;
338 	int exclusive;
339 	int metaonly;
340 
341 	int reserved_pebs;
342 	int vol_type;
343 	int usable_leb_size;
344 	int used_ebs;
345 	int last_eb_bytes;
346 	long long used_bytes;
347 	int alignment;
348 	int data_pad;
349 	int name_len;
350 	char name[UBI_VOL_NAME_MAX + 1];
351 
352 	int upd_ebs;
353 	int ch_lnum;
354 	long long upd_bytes;
355 	long long upd_received;
356 	void *upd_buf;
357 
358 	struct ubi_eba_table *eba_tbl;
359 	unsigned int skip_check:1;
360 	unsigned int checked:1;
361 	unsigned int corrupted:1;
362 	unsigned int upd_marker:1;
363 	unsigned int updating:1;
364 	unsigned int changing_leb:1;
365 	unsigned int direct_writes:1;
366 
367 #ifdef CONFIG_MTD_UBI_FASTMAP
368 	unsigned long *checkmap;
369 #endif
370 };
371 
372 /**
373  * struct ubi_volume_desc - UBI volume descriptor returned when it is opened.
374  * @vol: reference to the corresponding volume description object
375  * @mode: open mode (%UBI_READONLY, %UBI_READWRITE, %UBI_EXCLUSIVE
376  * or %UBI_METAONLY)
377  */
378 struct ubi_volume_desc {
379 	struct ubi_volume *vol;
380 	int mode;
381 };
382 
383 /**
384  * struct ubi_debug_info - debugging information for an UBI device.
385  *
386  * @chk_gen: if UBI general extra checks are enabled
387  * @chk_io: if UBI I/O extra checks are enabled
388  * @chk_fastmap: if UBI fastmap extra checks are enabled
389  * @disable_bgt: disable the background task for testing purposes
390  * @emulate_bitflips: emulate bit-flips for testing purposes
391  * @emulate_io_failures: emulate write/erase failures for testing purposes
392  * @emulate_power_cut: emulate power cut for testing purposes
393  * @power_cut_counter: count down for writes left until emulated power cut
394  * @power_cut_min: minimum number of writes before emulating a power cut
395  * @power_cut_max: maximum number of writes until emulating a power cut
396  * @emulate_failures: emulate failures for testing purposes
397  * @dfs_dir_name: name of debugfs directory containing files of this UBI device
398  * @dfs_dir: direntry object of the UBI device debugfs directory
399  * @dfs_chk_gen: debugfs knob to enable UBI general extra checks
400  * @dfs_chk_io: debugfs knob to enable UBI I/O extra checks
401  * @dfs_chk_fastmap: debugfs knob to enable UBI fastmap extra checks
402  * @dfs_disable_bgt: debugfs knob to disable the background task
403  * @dfs_emulate_bitflips: debugfs knob to emulate bit-flips
404  * @dfs_emulate_io_failures: debugfs knob to emulate write/erase failures
405  * @dfs_emulate_power_cut: debugfs knob to emulate power cuts
406  * @dfs_power_cut_min: debugfs knob for minimum writes before power cut
407  * @dfs_power_cut_max: debugfs knob for maximum writes until power cut
408  * @dfs_emulate_failures: debugfs entry to control the fault injection type
409  */
410 struct ubi_debug_info {
411 	unsigned int chk_gen:1;
412 	unsigned int chk_io:1;
413 	unsigned int chk_fastmap:1;
414 	unsigned int disable_bgt:1;
415 	unsigned int emulate_bitflips:1;
416 	unsigned int emulate_io_failures:1;
417 	unsigned int emulate_power_cut:2;
418 	unsigned int power_cut_counter;
419 	unsigned int power_cut_min;
420 	unsigned int power_cut_max;
421 	unsigned int emulate_failures;
422 	char dfs_dir_name[UBI_DFS_DIR_LEN + 1];
423 	struct dentry *dfs_dir;
424 	struct dentry *dfs_chk_gen;
425 	struct dentry *dfs_chk_io;
426 	struct dentry *dfs_chk_fastmap;
427 	struct dentry *dfs_disable_bgt;
428 	struct dentry *dfs_emulate_bitflips;
429 	struct dentry *dfs_emulate_io_failures;
430 	struct dentry *dfs_emulate_power_cut;
431 	struct dentry *dfs_power_cut_min;
432 	struct dentry *dfs_power_cut_max;
433 	struct dentry *dfs_emulate_failures;
434 };
435 
436 /**
437  * struct ubi_device - UBI device description structure
438  * @dev: UBI device object to use the Linux device model
439  * @cdev: character device object to create character device
440  * @ubi_num: UBI device number
441  * @ubi_name: UBI device name
442  * @vol_count: number of volumes in this UBI device
443  * @volumes: volumes of this UBI device
444  * @volumes_lock: protects @volumes, @rsvd_pebs, @avail_pebs, beb_rsvd_pebs,
445  *                @beb_rsvd_level, @bad_peb_count, @good_peb_count, @vol_count,
446  *                @vol->readers, @vol->writers, @vol->exclusive,
447  *                @vol->metaonly, @vol->ref_count, @vol->mapping and
448  *                @vol->eba_tbl.
449  * @ref_count: count of references on the UBI device
450  * @image_seq: image sequence number recorded on EC headers
451  *
452  * @rsvd_pebs: count of reserved physical eraseblocks
453  * @avail_pebs: count of available physical eraseblocks
454  * @beb_rsvd_pebs: how many physical eraseblocks are reserved for bad PEB
455  *                 handling
456  * @beb_rsvd_level: normal level of PEBs reserved for bad PEB handling
457  *
458  * @autoresize_vol_id: ID of the volume which has to be auto-resized at the end
459  *                     of UBI initialization
460  * @vtbl_slots: how many slots are available in the volume table
461  * @vtbl_size: size of the volume table in bytes
462  * @vtbl: in-RAM volume table copy
463  * @device_mutex: protects on-flash volume table and serializes volume
464  *                creation, deletion, update, re-size, re-name and set
465  *                property
466  *
467  * @max_ec: current highest erase counter value
468  * @mean_ec: current mean erase counter value
469  *
470  * @global_sqnum: global sequence number
471  * @ltree_lock: protects the lock tree and @global_sqnum
472  * @ltree: the lock tree
473  * @alc_mutex: serializes "atomic LEB change" operations
474  *
475  * @fm_disabled: non-zero if fastmap is disabled (default)
476  * @fm: in-memory data structure of the currently used fastmap
477  * @fm_pool: in-memory data structure of the fastmap pool
478  * @fm_wl_pool: in-memory data structure of the fastmap pool used by the WL
479  *		sub-system
480  * @fm_protect: serializes ubi_update_fastmap(), protects @fm_buf and makes sure
481  * that critical sections cannot be interrupted by ubi_update_fastmap()
482  * @fm_buf: vmalloc()'d buffer which holds the raw fastmap
483  * @fm_size: fastmap size in bytes
484  * @fm_eba_sem: allows ubi_update_fastmap() to block EBA table changes
485  * @fm_work: fastmap work queue
486  * @fm_work_scheduled: non-zero if fastmap work was scheduled
487  * @fast_attach: non-zero if UBI was attached by fastmap
488  * @fm_anchor: The next anchor PEB to use for fastmap
489  * @fm_do_produce_anchor: If true produce an anchor PEB in wl
490  * @fm_pool_rsv_cnt: Number of reserved PEBs for filling pool/wl_pool
491  *
492  * @used: RB-tree of used physical eraseblocks
493  * @erroneous: RB-tree of erroneous used physical eraseblocks
494  * @free: RB-tree of free physical eraseblocks
495  * @free_count: Contains the number of elements in @free
496  * @scrub: RB-tree of physical eraseblocks which need scrubbing
497  * @pq: protection queue (contain physical eraseblocks which are temporarily
498  *      protected from the wear-leveling worker)
499  * @pq_head: protection queue head
500  * @wl_lock: protects the @used, @free, @pq, @pq_head, @lookuptbl, @move_from,
501  *	     @move_to, @move_to_put @erase_pending, @wl_scheduled, @works,
502  *	     @erroneous, @erroneous_peb_count, @fm_work_scheduled, @fm_pool,
503  *	     and @fm_wl_pool fields
504  * @move_mutex: serializes eraseblock moves
505  * @work_sem: used to wait for all the scheduled works to finish and prevent
506  * new works from being submitted
507  * @wl_scheduled: non-zero if the wear-leveling was scheduled
508  * @lookuptbl: a table to quickly find a &struct ubi_wl_entry object for any
509  *             physical eraseblock
510  * @move_from: physical eraseblock from where the data is being moved
511  * @move_to: physical eraseblock where the data is being moved to
512  * @move_to_put: if the "to" PEB was put
513  * @works: list of pending works
514  * @works_count: count of pending works
515  * @bgt_thread: background thread description object
516  * @thread_enabled: if the background thread is enabled
517  * @bgt_name: background thread name
518  *
519  * @flash_size: underlying MTD device size (in bytes)
520  * @peb_count: count of physical eraseblocks on the MTD device
521  * @peb_size: physical eraseblock size
522  * @bad_peb_limit: top limit of expected bad physical eraseblocks
523  * @bad_peb_count: count of bad physical eraseblocks
524  * @good_peb_count: count of good physical eraseblocks
525  * @corr_peb_count: count of corrupted physical eraseblocks (preserved and not
526  *                  used by UBI)
527  * @erroneous_peb_count: count of erroneous physical eraseblocks in @erroneous
528  * @max_erroneous: maximum allowed amount of erroneous physical eraseblocks
529  * @min_io_size: minimal input/output unit size of the underlying MTD device
530  * @hdrs_min_io_size: minimal I/O unit size used for VID and EC headers
531  * @ro_mode: if the UBI device is in read-only mode
532  * @leb_size: logical eraseblock size
533  * @leb_start: starting offset of logical eraseblocks within physical
534  *             eraseblocks
535  * @ec_hdr_alsize: size of the EC header aligned to @hdrs_min_io_size
536  * @vid_hdr_alsize: size of the VID header aligned to @hdrs_min_io_size
537  * @vid_hdr_offset: starting offset of the volume identifier header (might be
538  *                  unaligned)
539  * @vid_hdr_aloffset: starting offset of the VID header aligned to
540  *                    @hdrs_min_io_size
541  * @vid_hdr_shift: contains @vid_hdr_offset - @vid_hdr_aloffset
542  * @bad_allowed: whether the MTD device admits bad physical eraseblocks or not
543  * @nor_flash: non-zero if working on top of NOR flash
544  * @max_write_size: maximum amount of bytes the underlying flash can write at a
545  *                  time (MTD write buffer size)
546  * @mtd: MTD device descriptor
547  *
548  * @peb_buf: a buffer of PEB size used for different purposes
549  * @buf_mutex: protects @peb_buf
550  * @ckvol_mutex: serializes static volume checking when opening
551  *
552  * @dbg: debugging information for this UBI device
553  */
554 struct ubi_device {
555 	struct cdev cdev;
556 	struct device dev;
557 	int ubi_num;
558 	char ubi_name[sizeof(UBI_NAME_STR)+5];
559 	int vol_count;
560 	struct ubi_volume *volumes[UBI_MAX_VOLUMES+UBI_INT_VOL_COUNT];
561 	spinlock_t volumes_lock;
562 	int ref_count;
563 	int image_seq;
564 
565 	int rsvd_pebs;
566 	int avail_pebs;
567 	int beb_rsvd_pebs;
568 	int beb_rsvd_level;
569 	int bad_peb_limit;
570 
571 	int autoresize_vol_id;
572 	int vtbl_slots;
573 	int vtbl_size;
574 	struct ubi_vtbl_record *vtbl;
575 	struct mutex device_mutex;
576 
577 	int max_ec;
578 	/* Note, mean_ec is not updated run-time - should be fixed */
579 	int mean_ec;
580 
581 	/* EBA sub-system's stuff */
582 	unsigned long long global_sqnum;
583 	spinlock_t ltree_lock;
584 	struct rb_root ltree;
585 	struct mutex alc_mutex;
586 
587 	/* Fastmap stuff */
588 	int fm_disabled;
589 	struct ubi_fastmap_layout *fm;
590 	struct ubi_fm_pool fm_pool;
591 	struct ubi_fm_pool fm_wl_pool;
592 	struct rw_semaphore fm_eba_sem;
593 	struct rw_semaphore fm_protect;
594 	void *fm_buf;
595 	size_t fm_size;
596 	struct work_struct fm_work;
597 	int fm_work_scheduled;
598 	int fast_attach;
599 	struct ubi_wl_entry *fm_anchor;
600 	int fm_do_produce_anchor;
601 	int fm_pool_rsv_cnt;
602 
603 	/* Wear-leveling sub-system's stuff */
604 	struct rb_root used;
605 	struct rb_root erroneous;
606 	struct rb_root free;
607 	int free_count;
608 	struct rb_root scrub;
609 	struct list_head pq[UBI_PROT_QUEUE_LEN];
610 	int pq_head;
611 	spinlock_t wl_lock;
612 	struct mutex move_mutex;
613 	struct rw_semaphore work_sem;
614 	int wl_scheduled;
615 	struct ubi_wl_entry **lookuptbl;
616 	struct ubi_wl_entry *move_from;
617 	struct ubi_wl_entry *move_to;
618 	int move_to_put;
619 	struct list_head works;
620 	int works_count;
621 	struct task_struct *bgt_thread;
622 	int thread_enabled;
623 	char bgt_name[sizeof(UBI_BGT_NAME_PATTERN)+2];
624 
625 	/* I/O sub-system's stuff */
626 	long long flash_size;
627 	int peb_count;
628 	int peb_size;
629 	int bad_peb_count;
630 	int good_peb_count;
631 	int corr_peb_count;
632 	int erroneous_peb_count;
633 	int max_erroneous;
634 	int min_io_size;
635 	int hdrs_min_io_size;
636 	int ro_mode;
637 	int leb_size;
638 	int leb_start;
639 	int ec_hdr_alsize;
640 	int vid_hdr_alsize;
641 	int vid_hdr_offset;
642 	int vid_hdr_aloffset;
643 	int vid_hdr_shift;
644 	unsigned int bad_allowed:1;
645 	unsigned int nor_flash:1;
646 	int max_write_size;
647 	struct mtd_info *mtd;
648 
649 	void *peb_buf;
650 	struct mutex buf_mutex;
651 	struct mutex ckvol_mutex;
652 
653 	struct ubi_debug_info dbg;
654 };
655 
656 /**
657  * struct ubi_ainf_peb - attach information about a physical eraseblock.
658  * @ec: erase counter (%UBI_UNKNOWN if it is unknown)
659  * @pnum: physical eraseblock number
660  * @vol_id: ID of the volume this LEB belongs to
661  * @lnum: logical eraseblock number
662  * @scrub: if this physical eraseblock needs scrubbing
663  * @copy_flag: this LEB is a copy (@copy_flag is set in VID header of this LEB)
664  * @sqnum: sequence number
665  * @u: unions RB-tree or @list links
666  * @u.rb: link in the per-volume RB-tree of &struct ubi_ainf_peb objects
667  * @u.list: link in one of the eraseblock lists
668  *
669  * One object of this type is allocated for each physical eraseblock when
670  * attaching an MTD device. Note, if this PEB does not belong to any LEB /
671  * volume, the @vol_id and @lnum fields are initialized to %UBI_UNKNOWN.
672  */
673 struct ubi_ainf_peb {
674 	int ec;
675 	int pnum;
676 	int vol_id;
677 	int lnum;
678 	unsigned int scrub:1;
679 	unsigned int copy_flag:1;
680 	unsigned long long sqnum;
681 	union {
682 		struct rb_node rb;
683 		struct list_head list;
684 	} u;
685 };
686 
687 /**
688  * struct ubi_ainf_volume - attaching information about a volume.
689  * @vol_id: volume ID
690  * @highest_lnum: highest logical eraseblock number in this volume
691  * @leb_count: number of logical eraseblocks in this volume
692  * @vol_type: volume type
693  * @used_ebs: number of used logical eraseblocks in this volume (only for
694  *            static volumes)
695  * @last_data_size: amount of data in the last logical eraseblock of this
696  *                  volume (always equivalent to the usable logical eraseblock
697  *                  size in case of dynamic volumes)
698  * @data_pad: how many bytes at the end of logical eraseblocks of this volume
699  *            are not used (due to volume alignment)
700  * @compat: compatibility flags of this volume
701  * @rb: link in the volume RB-tree
702  * @root: root of the RB-tree containing all the eraseblock belonging to this
703  *        volume (&struct ubi_ainf_peb objects)
704  *
705  * One object of this type is allocated for each volume when attaching an MTD
706  * device.
707  */
708 struct ubi_ainf_volume {
709 	int vol_id;
710 	int highest_lnum;
711 	int leb_count;
712 	int vol_type;
713 	int used_ebs;
714 	int last_data_size;
715 	int data_pad;
716 	int compat;
717 	struct rb_node rb;
718 	struct rb_root root;
719 };
720 
721 /**
722  * struct ubi_attach_info - MTD device attaching information.
723  * @volumes: root of the volume RB-tree
724  * @corr: list of corrupted physical eraseblocks
725  * @free: list of free physical eraseblocks
726  * @erase: list of physical eraseblocks which have to be erased
727  * @alien: list of physical eraseblocks which should not be used by UBI (e.g.,
728  *         those belonging to "preserve"-compatible internal volumes)
729  * @fastmap: list of physical eraseblocks which relate to fastmap (e.g.,
730  *           eraseblocks of the current and not yet erased old fastmap blocks)
731  * @corr_peb_count: count of PEBs in the @corr list
732  * @empty_peb_count: count of PEBs which are presumably empty (contain only
733  *                   0xFF bytes)
734  * @alien_peb_count: count of PEBs in the @alien list
735  * @bad_peb_count: count of bad physical eraseblocks
736  * @maybe_bad_peb_count: count of bad physical eraseblocks which are not marked
737  *                       as bad yet, but which look like bad
738  * @vols_found: number of volumes found
739  * @highest_vol_id: highest volume ID
740  * @is_empty: flag indicating whether the MTD device is empty or not
741  * @force_full_scan: flag indicating whether we need to do a full scan and drop
742 		     all existing Fastmap data structures
743  * @min_ec: lowest erase counter value
744  * @max_ec: highest erase counter value
745  * @max_sqnum: highest sequence number value
746  * @mean_ec: mean erase counter value
747  * @ec_sum: a temporary variable used when calculating @mean_ec
748  * @ec_count: a temporary variable used when calculating @mean_ec
749  * @aeb_slab_cache: slab cache for &struct ubi_ainf_peb objects
750  * @ech: temporary EC header. Only available during scan
751  * @vidh: temporary VID buffer. Only available during scan
752  *
753  * This data structure contains the result of attaching an MTD device and may
754  * be used by other UBI sub-systems to build final UBI data structures, further
755  * error-recovery and so on.
756  */
757 struct ubi_attach_info {
758 	struct rb_root volumes;
759 	struct list_head corr;
760 	struct list_head free;
761 	struct list_head erase;
762 	struct list_head alien;
763 	struct list_head fastmap;
764 	int corr_peb_count;
765 	int empty_peb_count;
766 	int alien_peb_count;
767 	int bad_peb_count;
768 	int maybe_bad_peb_count;
769 	int vols_found;
770 	int highest_vol_id;
771 	int is_empty;
772 	int force_full_scan;
773 	int min_ec;
774 	int max_ec;
775 	unsigned long long max_sqnum;
776 	int mean_ec;
777 	uint64_t ec_sum;
778 	int ec_count;
779 	struct kmem_cache *aeb_slab_cache;
780 	struct ubi_ec_hdr *ech;
781 	struct ubi_vid_io_buf *vidb;
782 };
783 
784 /**
785  * struct ubi_work - UBI work description data structure.
786  * @list: a link in the list of pending works
787  * @func: worker function
788  * @e: physical eraseblock to erase
789  * @vol_id: the volume ID on which this erasure is being performed
790  * @lnum: the logical eraseblock number
791  * @torture: if the physical eraseblock has to be tortured
792  *
793  * The @func pointer points to the worker function. If the @shutdown argument is
794  * not zero, the worker has to free the resources and exit immediately as the
795  * WL sub-system is shutting down.
796  * The worker has to return zero in case of success and a negative error code in
797  * case of failure.
798  */
799 struct ubi_work {
800 	struct list_head list;
801 	int (*func)(struct ubi_device *ubi, struct ubi_work *wrk, int shutdown);
802 	/* The below fields are only relevant to erasure works */
803 	struct ubi_wl_entry *e;
804 	int vol_id;
805 	int lnum;
806 	int torture;
807 };
808 
809 #include "debug.h"
810 
811 extern struct kmem_cache *ubi_wl_entry_slab;
812 extern const struct file_operations ubi_ctrl_cdev_operations;
813 extern const struct file_operations ubi_cdev_operations;
814 extern const struct file_operations ubi_vol_cdev_operations;
815 extern struct class ubi_class;
816 extern struct mutex ubi_devices_mutex;
817 extern struct blocking_notifier_head ubi_notifiers;
818 
819 /* attach.c */
820 struct ubi_ainf_peb *ubi_alloc_aeb(struct ubi_attach_info *ai, int pnum,
821 				   int ec);
822 void ubi_free_aeb(struct ubi_attach_info *ai, struct ubi_ainf_peb *aeb);
823 int ubi_add_to_av(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum,
824 		  int ec, const struct ubi_vid_hdr *vid_hdr, int bitflips);
825 struct ubi_ainf_volume *ubi_add_av(struct ubi_attach_info *ai, int vol_id);
826 struct ubi_ainf_volume *ubi_find_av(const struct ubi_attach_info *ai,
827 				    int vol_id);
828 void ubi_remove_av(struct ubi_attach_info *ai, struct ubi_ainf_volume *av);
829 struct ubi_ainf_peb *ubi_early_get_peb(struct ubi_device *ubi,
830 				       struct ubi_attach_info *ai);
831 int ubi_attach(struct ubi_device *ubi, int force_scan);
832 void ubi_destroy_ai(struct ubi_attach_info *ai);
833 
834 /* vtbl.c */
835 int ubi_change_vtbl_record(struct ubi_device *ubi, int idx,
836 			   struct ubi_vtbl_record *vtbl_rec);
837 int ubi_vtbl_rename_volumes(struct ubi_device *ubi,
838 			    struct list_head *rename_list);
839 int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_attach_info *ai);
840 
841 /* vmt.c */
842 int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req);
843 int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl);
844 int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs);
845 int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list);
846 int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol);
847 void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol);
848 
849 /* upd.c */
850 int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol,
851 		     long long bytes);
852 int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol,
853 			 const void __user *buf, int count);
854 int ubi_start_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
855 			 const struct ubi_leb_change_req *req);
856 int ubi_more_leb_change_data(struct ubi_device *ubi, struct ubi_volume *vol,
857 			     const void __user *buf, int count);
858 
859 /* misc.c */
860 int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf,
861 		      int length);
862 int ubi_check_volume(struct ubi_device *ubi, int vol_id);
863 void ubi_update_reserved(struct ubi_device *ubi);
864 void ubi_calculate_reserved(struct ubi_device *ubi);
865 int ubi_check_pattern(const void *buf, uint8_t patt, int size);
866 
867 static inline bool ubi_leb_valid(struct ubi_volume *vol, int lnum)
868 {
869 	return lnum >= 0 && lnum < vol->reserved_pebs;
870 }
871 
872 /* eba.c */
873 struct ubi_eba_table *ubi_eba_create_table(struct ubi_volume *vol,
874 					   int nentries);
875 void ubi_eba_destroy_table(struct ubi_eba_table *tbl);
876 void ubi_eba_copy_table(struct ubi_volume *vol, struct ubi_eba_table *dst,
877 			int nentries);
878 void ubi_eba_replace_table(struct ubi_volume *vol, struct ubi_eba_table *tbl);
879 void ubi_eba_get_ldesc(struct ubi_volume *vol, int lnum,
880 		       struct ubi_eba_leb_desc *ldesc);
881 bool ubi_eba_is_mapped(struct ubi_volume *vol, int lnum);
882 int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol,
883 		      int lnum);
884 int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
885 		     void *buf, int offset, int len, int check);
886 int ubi_eba_read_leb_sg(struct ubi_device *ubi, struct ubi_volume *vol,
887 			struct ubi_sgl *sgl, int lnum, int offset, int len,
888 			int check);
889 int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
890 		      const void *buf, int offset, int len);
891 int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol,
892 			 int lnum, const void *buf, int len, int used_ebs);
893 int ubi_eba_atomic_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
894 			      int lnum, const void *buf, int len);
895 int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
896 		     struct ubi_vid_io_buf *vidb);
897 int ubi_eba_init(struct ubi_device *ubi, struct ubi_attach_info *ai);
898 unsigned long long ubi_next_sqnum(struct ubi_device *ubi);
899 int self_check_eba(struct ubi_device *ubi, struct ubi_attach_info *ai_fastmap,
900 		   struct ubi_attach_info *ai_scan);
901 
902 /* wl.c */
903 int ubi_sync_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, int torture);
904 int ubi_wl_get_peb(struct ubi_device *ubi);
905 int ubi_wl_put_peb(struct ubi_device *ubi, int vol_id, int lnum,
906 		   int pnum, int torture);
907 int ubi_wl_flush(struct ubi_device *ubi, int vol_id, int lnum);
908 int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum);
909 int ubi_wl_init(struct ubi_device *ubi, struct ubi_attach_info *ai);
910 void ubi_wl_close(struct ubi_device *ubi);
911 int ubi_thread(void *u);
912 struct ubi_wl_entry *ubi_wl_get_fm_peb(struct ubi_device *ubi, int anchor);
913 int ubi_wl_put_fm_peb(struct ubi_device *ubi, struct ubi_wl_entry *used_e,
914 		      int lnum, int torture);
915 int ubi_is_erase_work(struct ubi_work *wrk);
916 void ubi_refill_pools_and_lock(struct ubi_device *ubi);
917 int ubi_ensure_anchor_pebs(struct ubi_device *ubi);
918 int ubi_bitflip_check(struct ubi_device *ubi, int pnum, int force_scrub);
919 
920 /* io.c */
921 int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset,
922 		int len);
923 int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
924 		 int len);
925 int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture);
926 int ubi_io_is_bad(const struct ubi_device *ubi, int pnum);
927 int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum);
928 int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum,
929 		       struct ubi_ec_hdr *ec_hdr, int verbose);
930 int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum,
931 			struct ubi_ec_hdr *ec_hdr);
932 int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum,
933 			struct ubi_vid_io_buf *vidb, int verbose);
934 int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum,
935 			 struct ubi_vid_io_buf *vidb);
936 
937 /* build.c */
938 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
939 		       int vid_hdr_offset, int max_beb_per1024,
940 		       bool disable_fm, bool need_resv_pool);
941 int ubi_detach_mtd_dev(int ubi_num, int anyway);
942 struct ubi_device *ubi_get_device(int ubi_num);
943 void ubi_put_device(struct ubi_device *ubi);
944 struct ubi_device *ubi_get_by_major(int major);
945 int ubi_major2num(int major);
946 int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol,
947 		      int ntype);
948 int ubi_notify_all(struct ubi_device *ubi, int ntype,
949 		   struct notifier_block *nb);
950 int ubi_enumerate_volumes(struct notifier_block *nb);
951 void ubi_free_all_volumes(struct ubi_device *ubi);
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 int ubi_fastmap_init_checkmap(struct ubi_volume *vol, int leb_count);
969 void ubi_fastmap_destroy_checkmap(struct ubi_volume *vol);
970 #else
971 static inline int ubi_update_fastmap(struct ubi_device *ubi) { return 0; }
972 static inline int ubi_fastmap_init_checkmap(struct ubi_volume *vol, int leb_count) { return 0; }
973 static inline void ubi_fastmap_destroy_checkmap(struct ubi_volume *vol) {}
974 #endif
975 
976 /* block.c */
977 #ifdef CONFIG_MTD_UBI_BLOCK
978 int ubiblock_init(void);
979 void ubiblock_exit(void);
980 int ubiblock_create(struct ubi_volume_info *vi);
981 int ubiblock_remove(struct ubi_volume_info *vi);
982 #else
983 static inline int ubiblock_init(void) { return 0; }
984 static inline void ubiblock_exit(void) {}
985 static inline int ubiblock_create(struct ubi_volume_info *vi)
986 {
987 	return -ENOSYS;
988 }
989 static inline int ubiblock_remove(struct ubi_volume_info *vi)
990 {
991 	return -ENOSYS;
992 }
993 #endif
994 
995 /*
996  * ubi_for_each_free_peb - walk the UBI free RB tree.
997  * @ubi: UBI device description object
998  * @e: a pointer to a ubi_wl_entry to use as cursor
999  * @pos: a pointer to RB-tree entry type to use as a loop counter
1000  */
1001 #define ubi_for_each_free_peb(ubi, e, tmp_rb)	\
1002 	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->free, u.rb)
1003 
1004 /*
1005  * ubi_for_each_used_peb - walk the UBI used RB tree.
1006  * @ubi: UBI device description object
1007  * @e: a pointer to a ubi_wl_entry to use as cursor
1008  * @pos: a pointer to RB-tree entry type to use as a loop counter
1009  */
1010 #define ubi_for_each_used_peb(ubi, e, tmp_rb)	\
1011 	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->used, u.rb)
1012 
1013 /*
1014  * ubi_for_each_scub_peb - walk the UBI scub RB tree.
1015  * @ubi: UBI device description object
1016  * @e: a pointer to a ubi_wl_entry to use as cursor
1017  * @pos: a pointer to RB-tree entry type to use as a loop counter
1018  */
1019 #define ubi_for_each_scrub_peb(ubi, e, tmp_rb)	\
1020 	ubi_rb_for_each_entry((tmp_rb), (e), &(ubi)->scrub, u.rb)
1021 
1022 /*
1023  * ubi_for_each_protected_peb - walk the UBI protection queue.
1024  * @ubi: UBI device description object
1025  * @i: a integer used as counter
1026  * @e: a pointer to a ubi_wl_entry to use as cursor
1027  */
1028 #define ubi_for_each_protected_peb(ubi, i, e)	\
1029 	for ((i) = 0; (i) < UBI_PROT_QUEUE_LEN; (i)++)	\
1030 		list_for_each_entry((e), &(ubi->pq[(i)]), u.list)
1031 
1032 /*
1033  * ubi_rb_for_each_entry - walk an RB-tree.
1034  * @rb: a pointer to type 'struct rb_node' to use as a loop counter
1035  * @pos: a pointer to RB-tree entry type to use as a loop counter
1036  * @root: RB-tree's root
1037  * @member: the name of the 'struct rb_node' within the RB-tree entry
1038  */
1039 #define ubi_rb_for_each_entry(rb, pos, root, member)                         \
1040 	for (rb = rb_first(root),                                            \
1041 	     pos = (rb ? container_of(rb, typeof(*pos), member) : NULL);     \
1042 	     rb;                                                             \
1043 	     rb = rb_next(rb),                                               \
1044 	     pos = (rb ? container_of(rb, typeof(*pos), member) : NULL))
1045 
1046 /*
1047  * ubi_move_aeb_to_list - move a PEB from the volume tree to a list.
1048  *
1049  * @av: volume attaching information
1050  * @aeb: attaching eraseblock information
1051  * @list: the list to move to
1052  */
1053 static inline void ubi_move_aeb_to_list(struct ubi_ainf_volume *av,
1054 					 struct ubi_ainf_peb *aeb,
1055 					 struct list_head *list)
1056 {
1057 		rb_erase(&aeb->u.rb, &av->root);
1058 		list_add_tail(&aeb->u.list, list);
1059 }
1060 
1061 /**
1062  * ubi_init_vid_buf - Initialize a VID buffer
1063  * @ubi: the UBI device
1064  * @vidb: the VID buffer to initialize
1065  * @buf: the underlying buffer
1066  */
1067 static inline void ubi_init_vid_buf(const struct ubi_device *ubi,
1068 				    struct ubi_vid_io_buf *vidb,
1069 				    void *buf)
1070 {
1071 	if (buf)
1072 		memset(buf, 0, ubi->vid_hdr_alsize);
1073 
1074 	vidb->buffer = buf;
1075 	vidb->hdr = buf + ubi->vid_hdr_shift;
1076 }
1077 
1078 /**
1079  * ubi_init_vid_buf - Allocate a VID buffer
1080  * @ubi: the UBI device
1081  * @gfp_flags: GFP flags to use for the allocation
1082  */
1083 static inline struct ubi_vid_io_buf *
1084 ubi_alloc_vid_buf(const struct ubi_device *ubi, gfp_t gfp_flags)
1085 {
1086 	struct ubi_vid_io_buf *vidb;
1087 	void *buf;
1088 
1089 	vidb = kzalloc(sizeof(*vidb), gfp_flags);
1090 	if (!vidb)
1091 		return NULL;
1092 
1093 	buf = kmalloc(ubi->vid_hdr_alsize, gfp_flags);
1094 	if (!buf) {
1095 		kfree(vidb);
1096 		return NULL;
1097 	}
1098 
1099 	ubi_init_vid_buf(ubi, vidb, buf);
1100 
1101 	return vidb;
1102 }
1103 
1104 /**
1105  * ubi_free_vid_buf - Free a VID buffer
1106  * @vidb: the VID buffer to free
1107  */
1108 static inline void ubi_free_vid_buf(struct ubi_vid_io_buf *vidb)
1109 {
1110 	if (!vidb)
1111 		return;
1112 
1113 	kfree(vidb->buffer);
1114 	kfree(vidb);
1115 }
1116 
1117 /**
1118  * ubi_get_vid_hdr - Get the VID header attached to a VID buffer
1119  * @vidb: VID buffer
1120  */
1121 static inline struct ubi_vid_hdr *ubi_get_vid_hdr(struct ubi_vid_io_buf *vidb)
1122 {
1123 	return vidb->hdr;
1124 }
1125 
1126 /**
1127  * ubi_ro_mode - switch to read-only mode.
1128  * @ubi: UBI device description object
1129  */
1130 static inline void ubi_ro_mode(struct ubi_device *ubi)
1131 {
1132 	if (!ubi->ro_mode) {
1133 		ubi->ro_mode = 1;
1134 		ubi_warn(ubi, "switch to read-only mode");
1135 		dump_stack();
1136 	}
1137 }
1138 
1139 /*
1140  * This function is equivalent to 'ubi_io_read()', but @offset is relative to
1141  * the beginning of the logical eraseblock, not to the beginning of the
1142  * physical eraseblock.
1143  */
1144 static inline int ubi_io_read_data(const struct ubi_device *ubi, void *buf,
1145 				   int pnum, int offset, int len)
1146 {
1147 	ubi_assert(offset >= 0);
1148 	return ubi_io_read(ubi, buf, pnum, offset + ubi->leb_start, len);
1149 }
1150 
1151 /*
1152  * This function is equivalent to 'ubi_io_write()', but @offset is relative to
1153  * the beginning of the logical eraseblock, not to the beginning of the
1154  * physical eraseblock.
1155  */
1156 static inline int ubi_io_write_data(struct ubi_device *ubi, const void *buf,
1157 				    int pnum, int offset, int len)
1158 {
1159 	ubi_assert(offset >= 0);
1160 
1161 	if (ubi_dbg_power_cut(ubi, MASK_POWER_CUT_DATA)) {
1162 		ubi_warn(ubi, "XXXXX emulating a power cut when writing data XXXXX");
1163 		ubi_ro_mode(ubi);
1164 		return -EROFS;
1165 	}
1166 	return ubi_io_write(ubi, buf, pnum, offset + ubi->leb_start, len);
1167 }
1168 
1169 /**
1170  * vol_id2idx - get table index by volume ID.
1171  * @ubi: UBI device description object
1172  * @vol_id: volume ID
1173  */
1174 static inline int vol_id2idx(const struct ubi_device *ubi, int vol_id)
1175 {
1176 	if (vol_id >= UBI_INTERNAL_VOL_START)
1177 		return vol_id - UBI_INTERNAL_VOL_START + ubi->vtbl_slots;
1178 	else
1179 		return vol_id;
1180 }
1181 
1182 /**
1183  * idx2vol_id - get volume ID by table index.
1184  * @ubi: UBI device description object
1185  * @idx: table index
1186  */
1187 static inline int idx2vol_id(const struct ubi_device *ubi, int idx)
1188 {
1189 	if (idx >= ubi->vtbl_slots)
1190 		return idx - ubi->vtbl_slots + UBI_INTERNAL_VOL_START;
1191 	else
1192 		return idx;
1193 }
1194 
1195 /**
1196  * ubi_is_fm_vol - check whether a volume ID is a Fastmap volume.
1197  * @vol_id: volume ID
1198  */
1199 static inline bool ubi_is_fm_vol(int vol_id)
1200 {
1201 	switch (vol_id) {
1202 		case UBI_FM_SB_VOLUME_ID:
1203 		case UBI_FM_DATA_VOLUME_ID:
1204 		return true;
1205 	}
1206 
1207 	return false;
1208 }
1209 
1210 /**
1211  * ubi_find_fm_block - check whether a PEB is part of the current Fastmap.
1212  * @ubi: UBI device description object
1213  * @pnum: physical eraseblock to look for
1214  *
1215  * This function returns a wear leveling object if @pnum relates to the current
1216  * fastmap, @NULL otherwise.
1217  */
1218 static inline struct ubi_wl_entry *ubi_find_fm_block(const struct ubi_device *ubi,
1219 						     int pnum)
1220 {
1221 	int i;
1222 
1223 	if (ubi->fm) {
1224 		for (i = 0; i < ubi->fm->used_blocks; i++) {
1225 			if (ubi->fm->e[i]->pnum == pnum)
1226 				return ubi->fm->e[i];
1227 		}
1228 	}
1229 
1230 	return NULL;
1231 }
1232 
1233 #endif /* !__UBI_UBI_H__ */
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