xref: /linux/fs/ubifs/ubifs.h (revision ae22a94997b8a03dcb3c922857c203246711f9d4)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * This file is part of UBIFS.
4  *
5  * Copyright (C) 2006-2008 Nokia Corporation
6  *
7  * Authors: Artem Bityutskiy (Битюцкий Артём)
8  *          Adrian Hunter
9  */
10 
11 #ifndef __UBIFS_H__
12 #define __UBIFS_H__
13 
14 #include <asm/div64.h>
15 #include <linux/statfs.h>
16 #include <linux/fs.h>
17 #include <linux/err.h>
18 #include <linux/sched.h>
19 #include <linux/slab.h>
20 #include <linux/vmalloc.h>
21 #include <linux/spinlock.h>
22 #include <linux/mutex.h>
23 #include <linux/rwsem.h>
24 #include <linux/mtd/ubi.h>
25 #include <linux/pagemap.h>
26 #include <linux/backing-dev.h>
27 #include <linux/security.h>
28 #include <linux/xattr.h>
29 #include <linux/random.h>
30 #include <linux/sysfs.h>
31 #include <linux/completion.h>
32 #include <crypto/hash_info.h>
33 #include <crypto/hash.h>
34 #include <crypto/utils.h>
35 
36 #include <linux/fscrypt.h>
37 
38 #include "ubifs-media.h"
39 
40 /* Version of this UBIFS implementation */
41 #define UBIFS_VERSION 1
42 
43 /* UBIFS file system VFS magic number */
44 #define UBIFS_SUPER_MAGIC 0x24051905
45 
46 /* Number of UBIFS blocks per VFS page */
47 #define UBIFS_BLOCKS_PER_PAGE (PAGE_SIZE / UBIFS_BLOCK_SIZE)
48 #define UBIFS_BLOCKS_PER_PAGE_SHIFT (PAGE_SHIFT - UBIFS_BLOCK_SHIFT)
49 
50 /* "File system end of life" sequence number watermark */
51 #define SQNUM_WARN_WATERMARK 0xFFFFFFFF00000000ULL
52 #define SQNUM_WATERMARK      0xFFFFFFFFFF000000ULL
53 
54 /*
55  * Minimum amount of LEBs reserved for the index. At present the index needs at
56  * least 2 LEBs: one for the index head and one for in-the-gaps method (which
57  * currently does not cater for the index head and so excludes it from
58  * consideration).
59  */
60 #define MIN_INDEX_LEBS 2
61 
62 /* Minimum amount of data UBIFS writes to the flash */
63 #define MIN_WRITE_SZ (UBIFS_DATA_NODE_SZ + 8)
64 
65 /*
66  * Currently we do not support inode number overlapping and re-using, so this
67  * watermark defines dangerous inode number level. This should be fixed later,
68  * although it is difficult to exceed current limit. Another option is to use
69  * 64-bit inode numbers, but this means more overhead.
70  */
71 #define INUM_WARN_WATERMARK 0xFFF00000
72 #define INUM_WATERMARK      0xFFFFFF00
73 
74 /* Maximum number of entries in each LPT (LEB category) heap */
75 #define LPT_HEAP_SZ 256
76 
77 /*
78  * Background thread name pattern. The numbers are UBI device and volume
79  * numbers.
80  */
81 #define BGT_NAME_PATTERN "ubifs_bgt%d_%d"
82 
83 /* Maximum possible inode number (only 32-bit inodes are supported now) */
84 #define MAX_INUM 0xFFFFFFFF
85 
86 /* Number of non-data journal heads */
87 #define NONDATA_JHEADS_CNT 2
88 
89 /* Shorter names for journal head numbers for internal usage */
90 #define GCHD   UBIFS_GC_HEAD
91 #define BASEHD UBIFS_BASE_HEAD
92 #define DATAHD UBIFS_DATA_HEAD
93 
94 /* 'No change' value for 'ubifs_change_lp()' */
95 #define LPROPS_NC 0x80000001
96 
97 /*
98  * There is no notion of truncation key because truncation nodes do not exist
99  * in TNC. However, when replaying, it is handy to introduce fake "truncation"
100  * keys for truncation nodes because the code becomes simpler. So we define
101  * %UBIFS_TRUN_KEY type.
102  *
103  * But otherwise, out of the journal reply scope, the truncation keys are
104  * invalid.
105  */
106 #define UBIFS_TRUN_KEY    UBIFS_KEY_TYPES_CNT
107 #define UBIFS_INVALID_KEY UBIFS_KEY_TYPES_CNT
108 
109 /*
110  * How much a directory entry/extended attribute entry adds to the parent/host
111  * inode.
112  */
113 #define CALC_DENT_SIZE(name_len) ALIGN(UBIFS_DENT_NODE_SZ + (name_len) + 1, 8)
114 
115 /* How much an extended attribute adds to the host inode */
116 #define CALC_XATTR_BYTES(data_len) ALIGN(UBIFS_INO_NODE_SZ + (data_len) + 1, 8)
117 
118 /*
119  * Znodes which were not touched for 'OLD_ZNODE_AGE' seconds are considered
120  * "old", and znode which were touched last 'YOUNG_ZNODE_AGE' seconds ago are
121  * considered "young". This is used by shrinker when selecting znode to trim
122  * off.
123  */
124 #define OLD_ZNODE_AGE 20
125 #define YOUNG_ZNODE_AGE 5
126 
127 /*
128  * Some compressors, like LZO, may end up with more data then the input buffer.
129  * So UBIFS always allocates larger output buffer, to be sure the compressor
130  * will not corrupt memory in case of worst case compression.
131  */
132 #define WORST_COMPR_FACTOR 2
133 
134 #ifdef CONFIG_FS_ENCRYPTION
135 #define UBIFS_CIPHER_BLOCK_SIZE FSCRYPT_CONTENTS_ALIGNMENT
136 #else
137 #define UBIFS_CIPHER_BLOCK_SIZE 0
138 #endif
139 
140 /*
141  * How much memory is needed for a buffer where we compress a data node.
142  */
143 #define COMPRESSED_DATA_NODE_BUF_SZ \
144 	(UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE * WORST_COMPR_FACTOR)
145 
146 /* Maximum expected tree height for use by bottom_up_buf */
147 #define BOTTOM_UP_HEIGHT 64
148 
149 /* Maximum number of data nodes to bulk-read */
150 #define UBIFS_MAX_BULK_READ 32
151 
152 #ifdef CONFIG_UBIFS_FS_AUTHENTICATION
153 #define UBIFS_HASH_ARR_SZ UBIFS_MAX_HASH_LEN
154 #define UBIFS_HMAC_ARR_SZ UBIFS_MAX_HMAC_LEN
155 #else
156 #define UBIFS_HASH_ARR_SZ 0
157 #define UBIFS_HMAC_ARR_SZ 0
158 #endif
159 
160 /*
161  * The UBIFS sysfs directory name pattern and maximum name length (3 for "ubi"
162  * + 1 for "_" and plus 2x2 for 2 UBI numbers and 1 for the trailing zero byte.
163  */
164 #define UBIFS_DFS_DIR_NAME "ubi%d_%d"
165 #define UBIFS_DFS_DIR_LEN  (3 + 1 + 2*2 + 1)
166 
167 /*
168  * Lockdep classes for UBIFS inode @ui_mutex.
169  */
170 enum {
171 	WB_MUTEX_1 = 0,
172 	WB_MUTEX_2 = 1,
173 	WB_MUTEX_3 = 2,
174 	WB_MUTEX_4 = 3,
175 };
176 
177 /*
178  * Znode flags (actually, bit numbers which store the flags).
179  *
180  * DIRTY_ZNODE: znode is dirty
181  * COW_ZNODE: znode is being committed and a new instance of this znode has to
182  *            be created before changing this znode
183  * OBSOLETE_ZNODE: znode is obsolete, which means it was deleted, but it is
184  *                 still in the commit list and the ongoing commit operation
185  *                 will commit it, and delete this znode after it is done
186  */
187 enum {
188 	DIRTY_ZNODE    = 0,
189 	COW_ZNODE      = 1,
190 	OBSOLETE_ZNODE = 2,
191 };
192 
193 /*
194  * Commit states.
195  *
196  * COMMIT_RESTING: commit is not wanted
197  * COMMIT_BACKGROUND: background commit has been requested
198  * COMMIT_REQUIRED: commit is required
199  * COMMIT_RUNNING_BACKGROUND: background commit is running
200  * COMMIT_RUNNING_REQUIRED: commit is running and it is required
201  * COMMIT_BROKEN: commit failed
202  */
203 enum {
204 	COMMIT_RESTING = 0,
205 	COMMIT_BACKGROUND,
206 	COMMIT_REQUIRED,
207 	COMMIT_RUNNING_BACKGROUND,
208 	COMMIT_RUNNING_REQUIRED,
209 	COMMIT_BROKEN,
210 };
211 
212 /*
213  * 'ubifs_scan_a_node()' return values.
214  *
215  * SCANNED_GARBAGE:  scanned garbage
216  * SCANNED_EMPTY_SPACE: scanned empty space
217  * SCANNED_A_NODE: scanned a valid node
218  * SCANNED_A_CORRUPT_NODE: scanned a corrupted node
219  * SCANNED_A_BAD_PAD_NODE: scanned a padding node with invalid pad length
220  *
221  * Greater than zero means: 'scanned that number of padding bytes'
222  */
223 enum {
224 	SCANNED_GARBAGE        = 0,
225 	SCANNED_EMPTY_SPACE    = -1,
226 	SCANNED_A_NODE         = -2,
227 	SCANNED_A_CORRUPT_NODE = -3,
228 	SCANNED_A_BAD_PAD_NODE = -4,
229 };
230 
231 /*
232  * LPT cnode flag bits.
233  *
234  * DIRTY_CNODE: cnode is dirty
235  * OBSOLETE_CNODE: cnode is being committed and has been copied (or deleted),
236  *                 so it can (and must) be freed when the commit is finished
237  * COW_CNODE: cnode is being committed and must be copied before writing
238  */
239 enum {
240 	DIRTY_CNODE    = 0,
241 	OBSOLETE_CNODE = 1,
242 	COW_CNODE      = 2,
243 };
244 
245 /*
246  * Dirty flag bits (lpt_drty_flgs) for LPT special nodes.
247  *
248  * LTAB_DIRTY: ltab node is dirty
249  * LSAVE_DIRTY: lsave node is dirty
250  */
251 enum {
252 	LTAB_DIRTY  = 1,
253 	LSAVE_DIRTY = 2,
254 };
255 
256 /*
257  * Return codes used by the garbage collector.
258  * @LEB_FREED: the logical eraseblock was freed and is ready to use
259  * @LEB_FREED_IDX: indexing LEB was freed and can be used only after the commit
260  * @LEB_RETAINED: the logical eraseblock was freed and retained for GC purposes
261  */
262 enum {
263 	LEB_FREED,
264 	LEB_FREED_IDX,
265 	LEB_RETAINED,
266 };
267 
268 /*
269  * Action taken upon a failed ubifs_assert().
270  * @ASSACT_REPORT: just report the failed assertion
271  * @ASSACT_RO: switch to read-only mode
272  * @ASSACT_PANIC: call BUG() and possible panic the kernel
273  */
274 enum {
275 	ASSACT_REPORT = 0,
276 	ASSACT_RO,
277 	ASSACT_PANIC,
278 };
279 
280 /**
281  * struct ubifs_old_idx - index node obsoleted since last commit start.
282  * @rb: rb-tree node
283  * @lnum: LEB number of obsoleted index node
284  * @offs: offset of obsoleted index node
285  */
286 struct ubifs_old_idx {
287 	struct rb_node rb;
288 	int lnum;
289 	int offs;
290 };
291 
292 /* The below union makes it easier to deal with keys */
293 union ubifs_key {
294 	uint8_t u8[UBIFS_SK_LEN];
295 	uint32_t u32[UBIFS_SK_LEN/4];
296 	uint64_t u64[UBIFS_SK_LEN/8];
297 	__le32 j32[UBIFS_SK_LEN/4];
298 };
299 
300 /**
301  * struct ubifs_scan_node - UBIFS scanned node information.
302  * @list: list of scanned nodes
303  * @key: key of node scanned (if it has one)
304  * @sqnum: sequence number
305  * @type: type of node scanned
306  * @offs: offset with LEB of node scanned
307  * @len: length of node scanned
308  * @node: raw node
309  */
310 struct ubifs_scan_node {
311 	struct list_head list;
312 	union ubifs_key key;
313 	unsigned long long sqnum;
314 	int type;
315 	int offs;
316 	int len;
317 	void *node;
318 };
319 
320 /**
321  * struct ubifs_scan_leb - UBIFS scanned LEB information.
322  * @lnum: logical eraseblock number
323  * @nodes_cnt: number of nodes scanned
324  * @nodes: list of struct ubifs_scan_node
325  * @endpt: end point (and therefore the start of empty space)
326  * @buf: buffer containing entire LEB scanned
327  */
328 struct ubifs_scan_leb {
329 	int lnum;
330 	int nodes_cnt;
331 	struct list_head nodes;
332 	int endpt;
333 	void *buf;
334 };
335 
336 /**
337  * struct ubifs_gced_idx_leb - garbage-collected indexing LEB.
338  * @list: list
339  * @lnum: LEB number
340  * @unmap: OK to unmap this LEB
341  *
342  * This data structure is used to temporary store garbage-collected indexing
343  * LEBs - they are not released immediately, but only after the next commit.
344  * This is needed to guarantee recoverability.
345  */
346 struct ubifs_gced_idx_leb {
347 	struct list_head list;
348 	int lnum;
349 	int unmap;
350 };
351 
352 /**
353  * struct ubifs_inode - UBIFS in-memory inode description.
354  * @vfs_inode: VFS inode description object
355  * @creat_sqnum: sequence number at time of creation
356  * @del_cmtno: commit number corresponding to the time the inode was deleted,
357  *             protected by @c->commit_sem;
358  * @xattr_size: summarized size of all extended attributes in bytes
359  * @xattr_cnt: count of extended attributes this inode has
360  * @xattr_names: sum of lengths of all extended attribute names belonging to
361  *               this inode
362  * @dirty: non-zero if the inode is dirty
363  * @xattr: non-zero if this is an extended attribute inode
364  * @bulk_read: non-zero if bulk-read should be used
365  * @ui_mutex: serializes inode write-back with the rest of VFS operations,
366  *            serializes "clean <-> dirty" state changes, serializes bulk-read,
367  *            protects @dirty, @bulk_read, @ui_size, and @xattr_size
368  * @xattr_sem: serilizes write operations (remove|set|create) on xattr
369  * @ui_lock: protects @synced_i_size
370  * @synced_i_size: synchronized size of inode, i.e. the value of inode size
371  *                 currently stored on the flash; used only for regular file
372  *                 inodes
373  * @ui_size: inode size used by UBIFS when writing to flash
374  * @flags: inode flags (@UBIFS_COMPR_FL, etc)
375  * @compr_type: default compression type used for this inode
376  * @last_page_read: page number of last page read (for bulk read)
377  * @read_in_a_row: number of consecutive pages read in a row (for bulk read)
378  * @data_len: length of the data attached to the inode
379  * @data: inode's data
380  *
381  * @ui_mutex exists for two main reasons. At first it prevents inodes from
382  * being written back while UBIFS changing them, being in the middle of an VFS
383  * operation. This way UBIFS makes sure the inode fields are consistent. For
384  * example, in 'ubifs_rename()' we change 4 inodes simultaneously, and
385  * write-back must not write any of them before we have finished.
386  *
387  * The second reason is budgeting - UBIFS has to budget all operations. If an
388  * operation is going to mark an inode dirty, it has to allocate budget for
389  * this. It cannot just mark it dirty because there is no guarantee there will
390  * be enough flash space to write the inode back later. This means UBIFS has
391  * to have full control over inode "clean <-> dirty" transitions (and pages
392  * actually). But unfortunately, VFS marks inodes dirty in many places, and it
393  * does not ask the file-system if it is allowed to do so (there is a notifier,
394  * but it is not enough), i.e., there is no mechanism to synchronize with this.
395  * So UBIFS has its own inode dirty flag and its own mutex to serialize
396  * "clean <-> dirty" transitions.
397  *
398  * The @synced_i_size field is used to make sure we never write pages which are
399  * beyond last synchronized inode size. See 'ubifs_writepage()' for more
400  * information.
401  *
402  * The @ui_size is a "shadow" variable for @inode->i_size and UBIFS uses
403  * @ui_size instead of @inode->i_size. The reason for this is that UBIFS cannot
404  * make sure @inode->i_size is always changed under @ui_mutex, because it
405  * cannot call 'truncate_setsize()' with @ui_mutex locked, because it would
406  * deadlock with 'ubifs_writepage()' (see file.c). All the other inode fields
407  * are changed under @ui_mutex, so they do not need "shadow" fields. Note, one
408  * could consider to rework locking and base it on "shadow" fields.
409  */
410 struct ubifs_inode {
411 	struct inode vfs_inode;
412 	unsigned long long creat_sqnum;
413 	unsigned long long del_cmtno;
414 	unsigned int xattr_size;
415 	unsigned int xattr_cnt;
416 	unsigned int xattr_names;
417 	unsigned int dirty:1;
418 	unsigned int xattr:1;
419 	unsigned int bulk_read:1;
420 	unsigned int compr_type:2;
421 	struct mutex ui_mutex;
422 	struct rw_semaphore xattr_sem;
423 	spinlock_t ui_lock;
424 	loff_t synced_i_size;
425 	loff_t ui_size;
426 	int flags;
427 	pgoff_t last_page_read;
428 	pgoff_t read_in_a_row;
429 	int data_len;
430 	void *data;
431 };
432 
433 /**
434  * struct ubifs_unclean_leb - records a LEB recovered under read-only mode.
435  * @list: list
436  * @lnum: LEB number of recovered LEB
437  * @endpt: offset where recovery ended
438  *
439  * This structure records a LEB identified during recovery that needs to be
440  * cleaned but was not because UBIFS was mounted read-only. The information
441  * is used to clean the LEB when remounting to read-write mode.
442  */
443 struct ubifs_unclean_leb {
444 	struct list_head list;
445 	int lnum;
446 	int endpt;
447 };
448 
449 /*
450  * LEB properties flags.
451  *
452  * LPROPS_UNCAT: not categorized
453  * LPROPS_DIRTY: dirty > free, dirty >= @c->dead_wm, not index
454  * LPROPS_DIRTY_IDX: dirty + free > @c->min_idx_node_sze and index
455  * LPROPS_FREE: free > 0, dirty < @c->dead_wm, not empty, not index
456  * LPROPS_HEAP_CNT: number of heaps used for storing categorized LEBs
457  * LPROPS_EMPTY: LEB is empty, not taken
458  * LPROPS_FREEABLE: free + dirty == leb_size, not index, not taken
459  * LPROPS_FRDI_IDX: free + dirty == leb_size and index, may be taken
460  * LPROPS_CAT_MASK: mask for the LEB categories above
461  * LPROPS_TAKEN: LEB was taken (this flag is not saved on the media)
462  * LPROPS_INDEX: LEB contains indexing nodes (this flag also exists on flash)
463  */
464 enum {
465 	LPROPS_UNCAT     =  0,
466 	LPROPS_DIRTY     =  1,
467 	LPROPS_DIRTY_IDX =  2,
468 	LPROPS_FREE      =  3,
469 	LPROPS_HEAP_CNT  =  3,
470 	LPROPS_EMPTY     =  4,
471 	LPROPS_FREEABLE  =  5,
472 	LPROPS_FRDI_IDX  =  6,
473 	LPROPS_CAT_MASK  = 15,
474 	LPROPS_TAKEN     = 16,
475 	LPROPS_INDEX     = 32,
476 };
477 
478 /**
479  * struct ubifs_lprops - logical eraseblock properties.
480  * @free: amount of free space in bytes
481  * @dirty: amount of dirty space in bytes
482  * @flags: LEB properties flags (see above)
483  * @lnum: LEB number
484  * @list: list of same-category lprops (for LPROPS_EMPTY and LPROPS_FREEABLE)
485  * @hpos: heap position in heap of same-category lprops (other categories)
486  */
487 struct ubifs_lprops {
488 	int free;
489 	int dirty;
490 	int flags;
491 	int lnum;
492 	union {
493 		struct list_head list;
494 		int hpos;
495 	};
496 };
497 
498 /**
499  * struct ubifs_lpt_lprops - LPT logical eraseblock properties.
500  * @free: amount of free space in bytes
501  * @dirty: amount of dirty space in bytes
502  * @tgc: trivial GC flag (1 => unmap after commit end)
503  * @cmt: commit flag (1 => reserved for commit)
504  */
505 struct ubifs_lpt_lprops {
506 	int free;
507 	int dirty;
508 	unsigned tgc:1;
509 	unsigned cmt:1;
510 };
511 
512 /**
513  * struct ubifs_lp_stats - statistics of eraseblocks in the main area.
514  * @empty_lebs: number of empty LEBs
515  * @taken_empty_lebs: number of taken LEBs
516  * @idx_lebs: number of indexing LEBs
517  * @total_free: total free space in bytes (includes all LEBs)
518  * @total_dirty: total dirty space in bytes (includes all LEBs)
519  * @total_used: total used space in bytes (does not include index LEBs)
520  * @total_dead: total dead space in bytes (does not include index LEBs)
521  * @total_dark: total dark space in bytes (does not include index LEBs)
522  *
523  * The @taken_empty_lebs field counts the LEBs that are in the transient state
524  * of having been "taken" for use but not yet written to. @taken_empty_lebs is
525  * needed to account correctly for @gc_lnum, otherwise @empty_lebs could be
526  * used by itself (in which case 'unused_lebs' would be a better name). In the
527  * case of @gc_lnum, it is "taken" at mount time or whenever a LEB is retained
528  * by GC, but unlike other empty LEBs that are "taken", it may not be written
529  * straight away (i.e. before the next commit start or unmount), so either
530  * @gc_lnum must be specially accounted for, or the current approach followed
531  * i.e. count it under @taken_empty_lebs.
532  *
533  * @empty_lebs includes @taken_empty_lebs.
534  *
535  * @total_used, @total_dead and @total_dark fields do not account indexing
536  * LEBs.
537  */
538 struct ubifs_lp_stats {
539 	int empty_lebs;
540 	int taken_empty_lebs;
541 	int idx_lebs;
542 	long long total_free;
543 	long long total_dirty;
544 	long long total_used;
545 	long long total_dead;
546 	long long total_dark;
547 };
548 
549 struct ubifs_nnode;
550 
551 /**
552  * struct ubifs_cnode - LEB Properties Tree common node.
553  * @parent: parent nnode
554  * @cnext: next cnode to commit
555  * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE)
556  * @iip: index in parent
557  * @level: level in the tree (zero for pnodes, greater than zero for nnodes)
558  * @num: node number
559  */
560 struct ubifs_cnode {
561 	struct ubifs_nnode *parent;
562 	struct ubifs_cnode *cnext;
563 	unsigned long flags;
564 	int iip;
565 	int level;
566 	int num;
567 };
568 
569 /**
570  * struct ubifs_pnode - LEB Properties Tree leaf node.
571  * @parent: parent nnode
572  * @cnext: next cnode to commit
573  * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE)
574  * @iip: index in parent
575  * @level: level in the tree (always zero for pnodes)
576  * @num: node number
577  * @lprops: LEB properties array
578  */
579 struct ubifs_pnode {
580 	struct ubifs_nnode *parent;
581 	struct ubifs_cnode *cnext;
582 	unsigned long flags;
583 	int iip;
584 	int level;
585 	int num;
586 	struct ubifs_lprops lprops[UBIFS_LPT_FANOUT];
587 };
588 
589 /**
590  * struct ubifs_nbranch - LEB Properties Tree internal node branch.
591  * @lnum: LEB number of child
592  * @offs: offset of child
593  * @nnode: nnode child
594  * @pnode: pnode child
595  * @cnode: cnode child
596  */
597 struct ubifs_nbranch {
598 	int lnum;
599 	int offs;
600 	union {
601 		struct ubifs_nnode *nnode;
602 		struct ubifs_pnode *pnode;
603 		struct ubifs_cnode *cnode;
604 	};
605 };
606 
607 /**
608  * struct ubifs_nnode - LEB Properties Tree internal node.
609  * @parent: parent nnode
610  * @cnext: next cnode to commit
611  * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE)
612  * @iip: index in parent
613  * @level: level in the tree (always greater than zero for nnodes)
614  * @num: node number
615  * @nbranch: branches to child nodes
616  */
617 struct ubifs_nnode {
618 	struct ubifs_nnode *parent;
619 	struct ubifs_cnode *cnext;
620 	unsigned long flags;
621 	int iip;
622 	int level;
623 	int num;
624 	struct ubifs_nbranch nbranch[UBIFS_LPT_FANOUT];
625 };
626 
627 /**
628  * struct ubifs_lpt_heap - heap of categorized lprops.
629  * @arr: heap array
630  * @cnt: number in heap
631  * @max_cnt: maximum number allowed in heap
632  *
633  * There are %LPROPS_HEAP_CNT heaps.
634  */
635 struct ubifs_lpt_heap {
636 	struct ubifs_lprops **arr;
637 	int cnt;
638 	int max_cnt;
639 };
640 
641 /*
642  * Return codes for LPT scan callback function.
643  *
644  * LPT_SCAN_CONTINUE: continue scanning
645  * LPT_SCAN_ADD: add the LEB properties scanned to the tree in memory
646  * LPT_SCAN_STOP: stop scanning
647  */
648 enum {
649 	LPT_SCAN_CONTINUE = 0,
650 	LPT_SCAN_ADD = 1,
651 	LPT_SCAN_STOP = 2,
652 };
653 
654 struct ubifs_info;
655 
656 /* Callback used by the 'ubifs_lpt_scan_nolock()' function */
657 typedef int (*ubifs_lpt_scan_callback)(struct ubifs_info *c,
658 				       const struct ubifs_lprops *lprops,
659 				       int in_tree, void *data);
660 
661 /**
662  * struct ubifs_wbuf - UBIFS write-buffer.
663  * @c: UBIFS file-system description object
664  * @buf: write-buffer (of min. flash I/O unit size)
665  * @lnum: logical eraseblock number the write-buffer points to
666  * @offs: write-buffer offset in this logical eraseblock
667  * @avail: number of bytes available in the write-buffer
668  * @used:  number of used bytes in the write-buffer
669  * @size: write-buffer size (in [@c->min_io_size, @c->max_write_size] range)
670  * @jhead: journal head the mutex belongs to (note, needed only to shut lockdep
671  *         up by 'mutex_lock_nested()).
672  * @sync_callback: write-buffer synchronization callback
673  * @io_mutex: serializes write-buffer I/O
674  * @lock: serializes @buf, @lnum, @offs, @avail, @used, @next_ino and @inodes
675  *        fields
676  * @timer: write-buffer timer
677  * @no_timer: non-zero if this write-buffer does not have a timer
678  * @need_sync: non-zero if the timer expired and the wbuf needs sync'ing
679  * @next_ino: points to the next position of the following inode number
680  * @inodes: stores the inode numbers of the nodes which are in wbuf
681  *
682  * The write-buffer synchronization callback is called when the write-buffer is
683  * synchronized in order to notify how much space was wasted due to
684  * write-buffer padding and how much free space is left in the LEB.
685  *
686  * Note: the fields @buf, @lnum, @offs, @avail and @used can be read under
687  * spin-lock or mutex because they are written under both mutex and spin-lock.
688  * @buf is appended to under mutex but overwritten under both mutex and
689  * spin-lock. Thus the data between @buf and @buf + @used can be read under
690  * spinlock.
691  */
692 struct ubifs_wbuf {
693 	struct ubifs_info *c;
694 	void *buf;
695 	int lnum;
696 	int offs;
697 	int avail;
698 	int used;
699 	int size;
700 	int jhead;
701 	int (*sync_callback)(struct ubifs_info *c, int lnum, int free, int pad);
702 	struct mutex io_mutex;
703 	spinlock_t lock;
704 	struct hrtimer timer;
705 	unsigned int no_timer:1;
706 	unsigned int need_sync:1;
707 	int next_ino;
708 	ino_t *inodes;
709 };
710 
711 /**
712  * struct ubifs_bud - bud logical eraseblock.
713  * @lnum: logical eraseblock number
714  * @start: where the (uncommitted) bud data starts
715  * @jhead: journal head number this bud belongs to
716  * @list: link in the list buds belonging to the same journal head
717  * @rb: link in the tree of all buds
718  * @log_hash: the log hash from the commit start node up to this bud
719  */
720 struct ubifs_bud {
721 	int lnum;
722 	int start;
723 	int jhead;
724 	struct list_head list;
725 	struct rb_node rb;
726 	struct shash_desc *log_hash;
727 };
728 
729 /**
730  * struct ubifs_jhead - journal head.
731  * @wbuf: head's write-buffer
732  * @buds_list: list of bud LEBs belonging to this journal head
733  * @grouped: non-zero if UBIFS groups nodes when writing to this journal head
734  * @log_hash: the log hash from the commit start node up to this journal head
735  *
736  * Note, the @buds list is protected by the @c->buds_lock.
737  */
738 struct ubifs_jhead {
739 	struct ubifs_wbuf wbuf;
740 	struct list_head buds_list;
741 	unsigned int grouped:1;
742 	struct shash_desc *log_hash;
743 };
744 
745 /**
746  * struct ubifs_zbranch - key/coordinate/length branch stored in znodes.
747  * @key: key
748  * @znode: znode address in memory
749  * @lnum: LEB number of the target node (indexing node or data node)
750  * @offs: target node offset within @lnum
751  * @len: target node length
752  * @hash: the hash of the target node
753  */
754 struct ubifs_zbranch {
755 	union ubifs_key key;
756 	union {
757 		struct ubifs_znode *znode;
758 		void *leaf;
759 	};
760 	int lnum;
761 	int offs;
762 	int len;
763 	u8 hash[UBIFS_HASH_ARR_SZ];
764 };
765 
766 /**
767  * struct ubifs_znode - in-memory representation of an indexing node.
768  * @parent: parent znode or NULL if it is the root
769  * @cnext: next znode to commit
770  * @cparent: parent node for this commit
771  * @ciip: index in cparent's zbranch array
772  * @flags: znode flags (%DIRTY_ZNODE, %COW_ZNODE or %OBSOLETE_ZNODE)
773  * @time: last access time (seconds)
774  * @level: level of the entry in the TNC tree
775  * @child_cnt: count of child znodes
776  * @iip: index in parent's zbranch array
777  * @alt: lower bound of key range has altered i.e. child inserted at slot 0
778  * @lnum: LEB number of the corresponding indexing node
779  * @offs: offset of the corresponding indexing node
780  * @len: length  of the corresponding indexing node
781  * @zbranch: array of znode branches (@c->fanout elements)
782  *
783  * Note! The @lnum, @offs, and @len fields are not really needed - we have them
784  * only for internal consistency check. They could be removed to save some RAM.
785  */
786 struct ubifs_znode {
787 	struct ubifs_znode *parent;
788 	struct ubifs_znode *cnext;
789 	struct ubifs_znode *cparent;
790 	int ciip;
791 	unsigned long flags;
792 	time64_t time;
793 	int level;
794 	int child_cnt;
795 	int iip;
796 	int alt;
797 	int lnum;
798 	int offs;
799 	int len;
800 	struct ubifs_zbranch zbranch[];
801 };
802 
803 /**
804  * struct bu_info - bulk-read information.
805  * @key: first data node key
806  * @zbranch: zbranches of data nodes to bulk read
807  * @buf: buffer to read into
808  * @buf_len: buffer length
809  * @gc_seq: GC sequence number to detect races with GC
810  * @cnt: number of data nodes for bulk read
811  * @blk_cnt: number of data blocks including holes
812  * @oef: end of file reached
813  */
814 struct bu_info {
815 	union ubifs_key key;
816 	struct ubifs_zbranch zbranch[UBIFS_MAX_BULK_READ];
817 	void *buf;
818 	int buf_len;
819 	int gc_seq;
820 	int cnt;
821 	int blk_cnt;
822 	int eof;
823 };
824 
825 /**
826  * struct ubifs_node_range - node length range description data structure.
827  * @len: fixed node length
828  * @min_len: minimum possible node length
829  * @max_len: maximum possible node length
830  *
831  * If @max_len is %0, the node has fixed length @len.
832  */
833 struct ubifs_node_range {
834 	union {
835 		int len;
836 		int min_len;
837 	};
838 	int max_len;
839 };
840 
841 /**
842  * struct ubifs_compressor - UBIFS compressor description structure.
843  * @compr_type: compressor type (%UBIFS_COMPR_LZO, etc)
844  * @cc: cryptoapi compressor handle
845  * @comp_mutex: mutex used during compression
846  * @decomp_mutex: mutex used during decompression
847  * @name: compressor name
848  * @capi_name: cryptoapi compressor name
849  */
850 struct ubifs_compressor {
851 	int compr_type;
852 	struct crypto_comp *cc;
853 	struct mutex *comp_mutex;
854 	struct mutex *decomp_mutex;
855 	const char *name;
856 	const char *capi_name;
857 };
858 
859 /**
860  * struct ubifs_budget_req - budget requirements of an operation.
861  *
862  * @fast: non-zero if the budgeting should try to acquire budget quickly and
863  *        should not try to call write-back
864  * @recalculate: non-zero if @idx_growth, @data_growth, and @dd_growth fields
865  *               have to be re-calculated
866  * @new_page: non-zero if the operation adds a new page
867  * @dirtied_page: non-zero if the operation makes a page dirty
868  * @new_dent: non-zero if the operation adds a new directory entry
869  * @mod_dent: non-zero if the operation removes or modifies an existing
870  *            directory entry
871  * @new_ino: non-zero if the operation adds a new inode
872  * @new_ino_d: how much data newly created inode contains
873  * @dirtied_ino: how many inodes the operation makes dirty
874  * @dirtied_ino_d: how much data dirtied inode contains
875  * @idx_growth: how much the index will supposedly grow
876  * @data_growth: how much new data the operation will supposedly add
877  * @dd_growth: how much data that makes other data dirty the operation will
878  *             supposedly add
879  *
880  * @idx_growth, @data_growth and @dd_growth are not used in budget request. The
881  * budgeting subsystem caches index and data growth values there to avoid
882  * re-calculating them when the budget is released. However, if @idx_growth is
883  * %-1, it is calculated by the release function using other fields.
884  *
885  * An inode may contain 4KiB of data at max., thus the widths of @new_ino_d
886  * is 13 bits, and @dirtied_ino_d - 15, because up to 4 inodes may be made
887  * dirty by the re-name operation.
888  *
889  * Note, UBIFS aligns node lengths to 8-bytes boundary, so the requester has to
890  * make sure the amount of inode data which contribute to @new_ino_d and
891  * @dirtied_ino_d fields are aligned.
892  */
893 struct ubifs_budget_req {
894 	unsigned int fast:1;
895 	unsigned int recalculate:1;
896 #ifndef UBIFS_DEBUG
897 	unsigned int new_page:1;
898 	unsigned int dirtied_page:1;
899 	unsigned int new_dent:1;
900 	unsigned int mod_dent:1;
901 	unsigned int new_ino:1;
902 	unsigned int new_ino_d:13;
903 	unsigned int dirtied_ino:4;
904 	unsigned int dirtied_ino_d:15;
905 #else
906 	/* Not bit-fields to check for overflows */
907 	unsigned int new_page;
908 	unsigned int dirtied_page;
909 	unsigned int new_dent;
910 	unsigned int mod_dent;
911 	unsigned int new_ino;
912 	unsigned int new_ino_d;
913 	unsigned int dirtied_ino;
914 	unsigned int dirtied_ino_d;
915 #endif
916 	int idx_growth;
917 	int data_growth;
918 	int dd_growth;
919 };
920 
921 /**
922  * struct ubifs_orphan - stores the inode number of an orphan.
923  * @rb: rb-tree node of rb-tree of orphans sorted by inode number
924  * @list: list head of list of orphans in order added
925  * @new_list: list head of list of orphans added since the last commit
926  * @child_list: list of xattr children if this orphan hosts xattrs, list head
927  * if this orphan is a xattr, not used otherwise.
928  * @cnext: next orphan to commit
929  * @dnext: next orphan to delete
930  * @inum: inode number
931  * @new: %1 => added since the last commit, otherwise %0
932  * @cmt: %1 => commit pending, otherwise %0
933  * @del: %1 => delete pending, otherwise %0
934  */
935 struct ubifs_orphan {
936 	struct rb_node rb;
937 	struct list_head list;
938 	struct list_head new_list;
939 	struct list_head child_list;
940 	struct ubifs_orphan *cnext;
941 	struct ubifs_orphan *dnext;
942 	ino_t inum;
943 	unsigned new:1;
944 	unsigned cmt:1;
945 	unsigned del:1;
946 };
947 
948 /**
949  * struct ubifs_mount_opts - UBIFS-specific mount options information.
950  * @unmount_mode: selected unmount mode (%0 default, %1 normal, %2 fast)
951  * @bulk_read: enable/disable bulk-reads (%0 default, %1 disable, %2 enable)
952  * @chk_data_crc: enable/disable CRC data checking when reading data nodes
953  *                (%0 default, %1 disable, %2 enable)
954  * @override_compr: override default compressor (%0 - do not override and use
955  *                  superblock compressor, %1 - override and use compressor
956  *                  specified in @compr_type)
957  * @compr_type: compressor type to override the superblock compressor with
958  *              (%UBIFS_COMPR_NONE, etc)
959  */
960 struct ubifs_mount_opts {
961 	unsigned int unmount_mode:2;
962 	unsigned int bulk_read:2;
963 	unsigned int chk_data_crc:2;
964 	unsigned int override_compr:1;
965 	unsigned int compr_type:2;
966 };
967 
968 /**
969  * struct ubifs_budg_info - UBIFS budgeting information.
970  * @idx_growth: amount of bytes budgeted for index growth
971  * @data_growth: amount of bytes budgeted for cached data
972  * @dd_growth: amount of bytes budgeted for cached data that will make
973  *             other data dirty
974  * @uncommitted_idx: amount of bytes were budgeted for growth of the index, but
975  *                   which still have to be taken into account because the index
976  *                   has not been committed so far
977  * @old_idx_sz: size of index on flash
978  * @min_idx_lebs: minimum number of LEBs required for the index
979  * @nospace: non-zero if the file-system does not have flash space (used as
980  *           optimization)
981  * @nospace_rp: the same as @nospace, but additionally means that even reserved
982  *              pool is full
983  * @page_budget: budget for a page (constant, never changed after mount)
984  * @inode_budget: budget for an inode (constant, never changed after mount)
985  * @dent_budget: budget for a directory entry (constant, never changed after
986  *               mount)
987  */
988 struct ubifs_budg_info {
989 	long long idx_growth;
990 	long long data_growth;
991 	long long dd_growth;
992 	long long uncommitted_idx;
993 	unsigned long long old_idx_sz;
994 	int min_idx_lebs;
995 	unsigned int nospace:1;
996 	unsigned int nospace_rp:1;
997 	int page_budget;
998 	int inode_budget;
999 	int dent_budget;
1000 };
1001 
1002 /**
1003  * ubifs_stats_info - per-FS statistics information.
1004  * @magic_errors: number of bad magic numbers (will be reset with a new mount).
1005  * @node_errors: number of bad nodes (will be reset with a new mount).
1006  * @crc_errors: number of bad crcs (will be reset with a new mount).
1007  */
1008 struct ubifs_stats_info {
1009 	unsigned int magic_errors;
1010 	unsigned int node_errors;
1011 	unsigned int crc_errors;
1012 };
1013 
1014 struct ubifs_debug_info;
1015 
1016 /**
1017  * struct ubifs_info - UBIFS file-system description data structure
1018  * (per-superblock).
1019  * @vfs_sb: VFS @struct super_block object
1020  * @sup_node: The super block node as read from the device
1021  *
1022  * @highest_inum: highest used inode number
1023  * @max_sqnum: current global sequence number
1024  * @cmt_no: commit number of the last successfully completed commit, protected
1025  *          by @commit_sem
1026  * @cnt_lock: protects @highest_inum and @max_sqnum counters
1027  * @fmt_version: UBIFS on-flash format version
1028  * @ro_compat_version: R/O compatibility version
1029  * @uuid: UUID from super block
1030  *
1031  * @lhead_lnum: log head logical eraseblock number
1032  * @lhead_offs: log head offset
1033  * @ltail_lnum: log tail logical eraseblock number (offset is always 0)
1034  * @log_mutex: protects the log, @lhead_lnum, @lhead_offs, @ltail_lnum, and
1035  *             @bud_bytes
1036  * @min_log_bytes: minimum required number of bytes in the log
1037  * @cmt_bud_bytes: used during commit to temporarily amount of bytes in
1038  *                 committed buds
1039  *
1040  * @buds: tree of all buds indexed by bud LEB number
1041  * @bud_bytes: how many bytes of flash is used by buds
1042  * @buds_lock: protects the @buds tree, @bud_bytes, and per-journal head bud
1043  *             lists
1044  * @jhead_cnt: count of journal heads
1045  * @jheads: journal heads (head zero is base head)
1046  * @max_bud_bytes: maximum number of bytes allowed in buds
1047  * @bg_bud_bytes: number of bud bytes when background commit is initiated
1048  * @old_buds: buds to be released after commit ends
1049  * @max_bud_cnt: maximum number of buds
1050  * @need_wait_space: Non %0 means space reservation tasks need to wait in queue
1051  * @reserve_space_wq: wait queue to sleep on if @need_wait_space is not %0
1052  *
1053  * @commit_sem: synchronizes committer with other processes
1054  * @cmt_state: commit state
1055  * @cs_lock: commit state lock
1056  * @cmt_wq: wait queue to sleep on if the log is full and a commit is running
1057  *
1058  * @big_lpt: flag that LPT is too big to write whole during commit
1059  * @space_fixup: flag indicating that free space in LEBs needs to be cleaned up
1060  * @double_hash: flag indicating that we can do lookups by hash
1061  * @encrypted: flag indicating that this file system contains encrypted files
1062  * @no_chk_data_crc: do not check CRCs when reading data nodes (except during
1063  *                   recovery)
1064  * @bulk_read: enable bulk-reads
1065  * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc)
1066  * @rw_incompat: the media is not R/W compatible
1067  * @assert_action: action to take when a ubifs_assert() fails
1068  * @authenticated: flag indigating the FS is mounted in authenticated mode
1069  *
1070  * @tnc_mutex: protects the Tree Node Cache (TNC), @zroot, @cnext, @enext, and
1071  *             @calc_idx_sz
1072  * @zroot: zbranch which points to the root index node and znode
1073  * @cnext: next znode to commit
1074  * @enext: next znode to commit to empty space
1075  * @gap_lebs: array of LEBs used by the in-gaps commit method
1076  * @cbuf: commit buffer
1077  * @ileb_buf: buffer for commit in-the-gaps method
1078  * @ileb_len: length of data in ileb_buf
1079  * @ihead_lnum: LEB number of index head
1080  * @ihead_offs: offset of index head
1081  * @ilebs: pre-allocated index LEBs
1082  * @ileb_cnt: number of pre-allocated index LEBs
1083  * @ileb_nxt: next pre-allocated index LEBs
1084  * @old_idx: tree of index nodes obsoleted since the last commit start
1085  * @bottom_up_buf: a buffer which is used by 'dirty_cow_bottom_up()' in tnc.c
1086  *
1087  * @mst_node: master node
1088  * @mst_offs: offset of valid master node
1089  *
1090  * @max_bu_buf_len: maximum bulk-read buffer length
1091  * @bu_mutex: protects the pre-allocated bulk-read buffer and @c->bu
1092  * @bu: pre-allocated bulk-read information
1093  *
1094  * @write_reserve_mutex: protects @write_reserve_buf
1095  * @write_reserve_buf: on the write path we allocate memory, which might
1096  *                     sometimes be unavailable, in which case we use this
1097  *                     write reserve buffer
1098  *
1099  * @log_lebs: number of logical eraseblocks in the log
1100  * @log_bytes: log size in bytes
1101  * @log_last: last LEB of the log
1102  * @lpt_lebs: number of LEBs used for lprops table
1103  * @lpt_first: first LEB of the lprops table area
1104  * @lpt_last: last LEB of the lprops table area
1105  * @orph_lebs: number of LEBs used for the orphan area
1106  * @orph_first: first LEB of the orphan area
1107  * @orph_last: last LEB of the orphan area
1108  * @main_lebs: count of LEBs in the main area
1109  * @main_first: first LEB of the main area
1110  * @main_bytes: main area size in bytes
1111  *
1112  * @key_hash_type: type of the key hash
1113  * @key_hash: direntry key hash function
1114  * @key_fmt: key format
1115  * @key_len: key length
1116  * @hash_len: The length of the index node hashes
1117  * @fanout: fanout of the index tree (number of links per indexing node)
1118  *
1119  * @min_io_size: minimal input/output unit size
1120  * @min_io_shift: number of bits in @min_io_size minus one
1121  * @max_write_size: maximum amount of bytes the underlying flash can write at a
1122  *                  time (MTD write buffer size)
1123  * @max_write_shift: number of bits in @max_write_size minus one
1124  * @leb_size: logical eraseblock size in bytes
1125  * @leb_start: starting offset of logical eraseblocks within physical
1126  *             eraseblocks
1127  * @half_leb_size: half LEB size
1128  * @idx_leb_size: how many bytes of an LEB are effectively available when it is
1129  *                used to store indexing nodes (@leb_size - @max_idx_node_sz)
1130  * @leb_cnt: count of logical eraseblocks
1131  * @max_leb_cnt: maximum count of logical eraseblocks
1132  * @ro_media: the underlying UBI volume is read-only
1133  * @ro_mount: the file-system was mounted as read-only
1134  * @ro_error: UBIFS switched to R/O mode because an error happened
1135  *
1136  * @dirty_pg_cnt: number of dirty pages (not used)
1137  * @dirty_zn_cnt: number of dirty znodes
1138  * @clean_zn_cnt: number of clean znodes
1139  *
1140  * @space_lock: protects @bi and @lst
1141  * @lst: lprops statistics
1142  * @bi: budgeting information
1143  * @calc_idx_sz: temporary variable which is used to calculate new index size
1144  *               (contains accurate new index size at end of TNC commit start)
1145  *
1146  * @ref_node_alsz: size of the LEB reference node aligned to the min. flash
1147  *                 I/O unit
1148  * @mst_node_alsz: master node aligned size
1149  * @min_idx_node_sz: minimum indexing node aligned on 8-bytes boundary
1150  * @max_idx_node_sz: maximum indexing node aligned on 8-bytes boundary
1151  * @max_inode_sz: maximum possible inode size in bytes
1152  * @max_znode_sz: size of znode in bytes
1153  *
1154  * @leb_overhead: how many bytes are wasted in an LEB when it is filled with
1155  *                data nodes of maximum size - used in free space reporting
1156  * @dead_wm: LEB dead space watermark
1157  * @dark_wm: LEB dark space watermark
1158  * @block_cnt: count of 4KiB blocks on the FS
1159  *
1160  * @ranges: UBIFS node length ranges
1161  * @ubi: UBI volume descriptor
1162  * @di: UBI device information
1163  * @vi: UBI volume information
1164  *
1165  * @orph_tree: rb-tree of orphan inode numbers
1166  * @orph_list: list of orphan inode numbers in order added
1167  * @orph_new: list of orphan inode numbers added since last commit
1168  * @orph_cnext: next orphan to commit
1169  * @orph_dnext: next orphan to delete
1170  * @orphan_lock: lock for orph_tree and orph_new
1171  * @orph_buf: buffer for orphan nodes
1172  * @new_orphans: number of orphans since last commit
1173  * @cmt_orphans: number of orphans being committed
1174  * @tot_orphans: number of orphans in the rb_tree
1175  * @max_orphans: maximum number of orphans allowed
1176  * @ohead_lnum: orphan head LEB number
1177  * @ohead_offs: orphan head offset
1178  * @no_orphs: non-zero if there are no orphans
1179  *
1180  * @bgt: UBIFS background thread
1181  * @bgt_name: background thread name
1182  * @need_bgt: if background thread should run
1183  * @need_wbuf_sync: if write-buffers have to be synchronized
1184  *
1185  * @gc_lnum: LEB number used for garbage collection
1186  * @sbuf: a buffer of LEB size used by GC and replay for scanning
1187  * @idx_gc: list of index LEBs that have been garbage collected
1188  * @idx_gc_cnt: number of elements on the idx_gc list
1189  * @gc_seq: incremented for every non-index LEB garbage collected
1190  * @gced_lnum: last non-index LEB that was garbage collected
1191  *
1192  * @infos_list: links all 'ubifs_info' objects
1193  * @umount_mutex: serializes shrinker and un-mount
1194  * @shrinker_run_no: shrinker run number
1195  *
1196  * @space_bits: number of bits needed to record free or dirty space
1197  * @lpt_lnum_bits: number of bits needed to record a LEB number in the LPT
1198  * @lpt_offs_bits: number of bits needed to record an offset in the LPT
1199  * @lpt_spc_bits: number of bits needed to space in the LPT
1200  * @pcnt_bits: number of bits needed to record pnode or nnode number
1201  * @lnum_bits: number of bits needed to record LEB number
1202  * @nnode_sz: size of on-flash nnode
1203  * @pnode_sz: size of on-flash pnode
1204  * @ltab_sz: size of on-flash LPT lprops table
1205  * @lsave_sz: size of on-flash LPT save table
1206  * @pnode_cnt: number of pnodes
1207  * @nnode_cnt: number of nnodes
1208  * @lpt_hght: height of the LPT
1209  * @pnodes_have: number of pnodes in memory
1210  *
1211  * @lp_mutex: protects lprops table and all the other lprops-related fields
1212  * @lpt_lnum: LEB number of the root nnode of the LPT
1213  * @lpt_offs: offset of the root nnode of the LPT
1214  * @nhead_lnum: LEB number of LPT head
1215  * @nhead_offs: offset of LPT head
1216  * @lpt_drty_flgs: dirty flags for LPT special nodes e.g. ltab
1217  * @dirty_nn_cnt: number of dirty nnodes
1218  * @dirty_pn_cnt: number of dirty pnodes
1219  * @check_lpt_free: flag that indicates LPT GC may be needed
1220  * @lpt_sz: LPT size
1221  * @lpt_nod_buf: buffer for an on-flash nnode or pnode
1222  * @lpt_buf: buffer of LEB size used by LPT
1223  * @nroot: address in memory of the root nnode of the LPT
1224  * @lpt_cnext: next LPT node to commit
1225  * @lpt_heap: array of heaps of categorized lprops
1226  * @dirty_idx: a (reverse sorted) copy of the LPROPS_DIRTY_IDX heap as at
1227  *             previous commit start
1228  * @uncat_list: list of un-categorized LEBs
1229  * @empty_list: list of empty LEBs
1230  * @freeable_list: list of freeable non-index LEBs (free + dirty == @leb_size)
1231  * @frdi_idx_list: list of freeable index LEBs (free + dirty == @leb_size)
1232  * @freeable_cnt: number of freeable LEBs in @freeable_list
1233  * @in_a_category_cnt: count of lprops which are in a certain category, which
1234  *                     basically meants that they were loaded from the flash
1235  *
1236  * @ltab_lnum: LEB number of LPT's own lprops table
1237  * @ltab_offs: offset of LPT's own lprops table
1238  * @ltab: LPT's own lprops table
1239  * @ltab_cmt: LPT's own lprops table (commit copy)
1240  * @lsave_cnt: number of LEB numbers in LPT's save table
1241  * @lsave_lnum: LEB number of LPT's save table
1242  * @lsave_offs: offset of LPT's save table
1243  * @lsave: LPT's save table
1244  * @lscan_lnum: LEB number of last LPT scan
1245  *
1246  * @rp_size: size of the reserved pool in bytes
1247  * @report_rp_size: size of the reserved pool reported to user-space
1248  * @rp_uid: reserved pool user ID
1249  * @rp_gid: reserved pool group ID
1250  *
1251  * @hash_tfm: the hash transformation used for hashing nodes
1252  * @hmac_tfm: the HMAC transformation for this filesystem
1253  * @hmac_desc_len: length of the HMAC used for authentication
1254  * @auth_key_name: the authentication key name
1255  * @auth_hash_name: the name of the hash algorithm used for authentication
1256  * @auth_hash_algo: the authentication hash used for this fs
1257  * @log_hash: the log hash from the commit start node up to the latest reference
1258  *            node.
1259  *
1260  * @empty: %1 if the UBI device is empty
1261  * @need_recovery: %1 if the file-system needs recovery
1262  * @replaying: %1 during journal replay
1263  * @mounting: %1 while mounting
1264  * @probing: %1 while attempting to mount if SB_SILENT mount flag is set
1265  * @remounting_rw: %1 while re-mounting from R/O mode to R/W mode
1266  * @replay_list: temporary list used during journal replay
1267  * @replay_buds: list of buds to replay
1268  * @cs_sqnum: sequence number of first node in the log (commit start node)
1269  * @unclean_leb_list: LEBs to recover when re-mounting R/O mounted FS to R/W
1270  *                    mode
1271  * @rcvrd_mst_node: recovered master node to write when re-mounting R/O mounted
1272  *                  FS to R/W mode
1273  * @size_tree: inode size information for recovery
1274  * @mount_opts: UBIFS-specific mount options
1275  *
1276  * @dbg: debugging-related information
1277  * @stats: statistics exported over sysfs
1278  *
1279  * @kobj: kobject for /sys/fs/ubifs/
1280  * @kobj_unregister: completion to unregister sysfs kobject
1281  */
1282 struct ubifs_info {
1283 	struct super_block *vfs_sb;
1284 	struct ubifs_sb_node *sup_node;
1285 
1286 	ino_t highest_inum;
1287 	unsigned long long max_sqnum;
1288 	unsigned long long cmt_no;
1289 	spinlock_t cnt_lock;
1290 	int fmt_version;
1291 	int ro_compat_version;
1292 	unsigned char uuid[16];
1293 
1294 	int lhead_lnum;
1295 	int lhead_offs;
1296 	int ltail_lnum;
1297 	struct mutex log_mutex;
1298 	int min_log_bytes;
1299 	long long cmt_bud_bytes;
1300 
1301 	struct rb_root buds;
1302 	long long bud_bytes;
1303 	spinlock_t buds_lock;
1304 	int jhead_cnt;
1305 	struct ubifs_jhead *jheads;
1306 	long long max_bud_bytes;
1307 	long long bg_bud_bytes;
1308 	struct list_head old_buds;
1309 	int max_bud_cnt;
1310 	atomic_t need_wait_space;
1311 	wait_queue_head_t reserve_space_wq;
1312 
1313 	struct rw_semaphore commit_sem;
1314 	int cmt_state;
1315 	spinlock_t cs_lock;
1316 	wait_queue_head_t cmt_wq;
1317 
1318 	struct kobject kobj;
1319 	struct completion kobj_unregister;
1320 
1321 	unsigned int big_lpt:1;
1322 	unsigned int space_fixup:1;
1323 	unsigned int double_hash:1;
1324 	unsigned int encrypted:1;
1325 	unsigned int no_chk_data_crc:1;
1326 	unsigned int bulk_read:1;
1327 	unsigned int default_compr:2;
1328 	unsigned int rw_incompat:1;
1329 	unsigned int assert_action:2;
1330 	unsigned int authenticated:1;
1331 	unsigned int superblock_need_write:1;
1332 
1333 	struct mutex tnc_mutex;
1334 	struct ubifs_zbranch zroot;
1335 	struct ubifs_znode *cnext;
1336 	struct ubifs_znode *enext;
1337 	int *gap_lebs;
1338 	void *cbuf;
1339 	void *ileb_buf;
1340 	int ileb_len;
1341 	int ihead_lnum;
1342 	int ihead_offs;
1343 	int *ilebs;
1344 	int ileb_cnt;
1345 	int ileb_nxt;
1346 	struct rb_root old_idx;
1347 	int *bottom_up_buf;
1348 
1349 	struct ubifs_mst_node *mst_node;
1350 	int mst_offs;
1351 
1352 	int max_bu_buf_len;
1353 	struct mutex bu_mutex;
1354 	struct bu_info bu;
1355 
1356 	struct mutex write_reserve_mutex;
1357 	void *write_reserve_buf;
1358 
1359 	int log_lebs;
1360 	long long log_bytes;
1361 	int log_last;
1362 	int lpt_lebs;
1363 	int lpt_first;
1364 	int lpt_last;
1365 	int orph_lebs;
1366 	int orph_first;
1367 	int orph_last;
1368 	int main_lebs;
1369 	int main_first;
1370 	long long main_bytes;
1371 
1372 	uint8_t key_hash_type;
1373 	uint32_t (*key_hash)(const char *str, int len);
1374 	int key_fmt;
1375 	int key_len;
1376 	int hash_len;
1377 	int fanout;
1378 
1379 	int min_io_size;
1380 	int min_io_shift;
1381 	int max_write_size;
1382 	int max_write_shift;
1383 	int leb_size;
1384 	int leb_start;
1385 	int half_leb_size;
1386 	int idx_leb_size;
1387 	int leb_cnt;
1388 	int max_leb_cnt;
1389 	unsigned int ro_media:1;
1390 	unsigned int ro_mount:1;
1391 	unsigned int ro_error:1;
1392 
1393 	atomic_long_t dirty_pg_cnt;
1394 	atomic_long_t dirty_zn_cnt;
1395 	atomic_long_t clean_zn_cnt;
1396 
1397 	spinlock_t space_lock;
1398 	struct ubifs_lp_stats lst;
1399 	struct ubifs_budg_info bi;
1400 	unsigned long long calc_idx_sz;
1401 
1402 	int ref_node_alsz;
1403 	int mst_node_alsz;
1404 	int min_idx_node_sz;
1405 	int max_idx_node_sz;
1406 	long long max_inode_sz;
1407 	int max_znode_sz;
1408 
1409 	int leb_overhead;
1410 	int dead_wm;
1411 	int dark_wm;
1412 	int block_cnt;
1413 
1414 	struct ubifs_node_range ranges[UBIFS_NODE_TYPES_CNT];
1415 	struct ubi_volume_desc *ubi;
1416 	struct ubi_device_info di;
1417 	struct ubi_volume_info vi;
1418 
1419 	struct rb_root orph_tree;
1420 	struct list_head orph_list;
1421 	struct list_head orph_new;
1422 	struct ubifs_orphan *orph_cnext;
1423 	struct ubifs_orphan *orph_dnext;
1424 	spinlock_t orphan_lock;
1425 	void *orph_buf;
1426 	int new_orphans;
1427 	int cmt_orphans;
1428 	int tot_orphans;
1429 	int max_orphans;
1430 	int ohead_lnum;
1431 	int ohead_offs;
1432 	int no_orphs;
1433 
1434 	struct task_struct *bgt;
1435 	char bgt_name[sizeof(BGT_NAME_PATTERN) + 9];
1436 	int need_bgt;
1437 	int need_wbuf_sync;
1438 
1439 	int gc_lnum;
1440 	void *sbuf;
1441 	struct list_head idx_gc;
1442 	int idx_gc_cnt;
1443 	int gc_seq;
1444 	int gced_lnum;
1445 
1446 	struct list_head infos_list;
1447 	struct mutex umount_mutex;
1448 	unsigned int shrinker_run_no;
1449 
1450 	int space_bits;
1451 	int lpt_lnum_bits;
1452 	int lpt_offs_bits;
1453 	int lpt_spc_bits;
1454 	int pcnt_bits;
1455 	int lnum_bits;
1456 	int nnode_sz;
1457 	int pnode_sz;
1458 	int ltab_sz;
1459 	int lsave_sz;
1460 	int pnode_cnt;
1461 	int nnode_cnt;
1462 	int lpt_hght;
1463 	int pnodes_have;
1464 
1465 	struct mutex lp_mutex;
1466 	int lpt_lnum;
1467 	int lpt_offs;
1468 	int nhead_lnum;
1469 	int nhead_offs;
1470 	int lpt_drty_flgs;
1471 	int dirty_nn_cnt;
1472 	int dirty_pn_cnt;
1473 	int check_lpt_free;
1474 	long long lpt_sz;
1475 	void *lpt_nod_buf;
1476 	void *lpt_buf;
1477 	struct ubifs_nnode *nroot;
1478 	struct ubifs_cnode *lpt_cnext;
1479 	struct ubifs_lpt_heap lpt_heap[LPROPS_HEAP_CNT];
1480 	struct ubifs_lpt_heap dirty_idx;
1481 	struct list_head uncat_list;
1482 	struct list_head empty_list;
1483 	struct list_head freeable_list;
1484 	struct list_head frdi_idx_list;
1485 	int freeable_cnt;
1486 	int in_a_category_cnt;
1487 
1488 	int ltab_lnum;
1489 	int ltab_offs;
1490 	struct ubifs_lpt_lprops *ltab;
1491 	struct ubifs_lpt_lprops *ltab_cmt;
1492 	int lsave_cnt;
1493 	int lsave_lnum;
1494 	int lsave_offs;
1495 	int *lsave;
1496 	int lscan_lnum;
1497 
1498 	long long rp_size;
1499 	long long report_rp_size;
1500 	kuid_t rp_uid;
1501 	kgid_t rp_gid;
1502 
1503 	struct crypto_shash *hash_tfm;
1504 	struct crypto_shash *hmac_tfm;
1505 	int hmac_desc_len;
1506 	char *auth_key_name;
1507 	char *auth_hash_name;
1508 	enum hash_algo auth_hash_algo;
1509 
1510 	struct shash_desc *log_hash;
1511 
1512 	/* The below fields are used only during mounting and re-mounting */
1513 	unsigned int empty:1;
1514 	unsigned int need_recovery:1;
1515 	unsigned int replaying:1;
1516 	unsigned int mounting:1;
1517 	unsigned int remounting_rw:1;
1518 	unsigned int probing:1;
1519 	struct list_head replay_list;
1520 	struct list_head replay_buds;
1521 	unsigned long long cs_sqnum;
1522 	struct list_head unclean_leb_list;
1523 	struct ubifs_mst_node *rcvrd_mst_node;
1524 	struct rb_root size_tree;
1525 	struct ubifs_mount_opts mount_opts;
1526 
1527 	struct ubifs_debug_info *dbg;
1528 	struct ubifs_stats_info *stats;
1529 };
1530 
1531 extern struct list_head ubifs_infos;
1532 extern spinlock_t ubifs_infos_lock;
1533 extern atomic_long_t ubifs_clean_zn_cnt;
1534 extern const struct super_operations ubifs_super_operations;
1535 extern const struct address_space_operations ubifs_file_address_operations;
1536 extern const struct file_operations ubifs_file_operations;
1537 extern const struct inode_operations ubifs_file_inode_operations;
1538 extern const struct file_operations ubifs_dir_operations;
1539 extern const struct inode_operations ubifs_dir_inode_operations;
1540 extern const struct inode_operations ubifs_symlink_inode_operations;
1541 extern struct ubifs_compressor *ubifs_compressors[UBIFS_COMPR_TYPES_CNT];
1542 extern int ubifs_default_version;
1543 
1544 /* auth.c */
1545 static inline int ubifs_authenticated(const struct ubifs_info *c)
1546 {
1547 	return (IS_ENABLED(CONFIG_UBIFS_FS_AUTHENTICATION)) && c->authenticated;
1548 }
1549 
1550 struct shash_desc *__ubifs_hash_get_desc(const struct ubifs_info *c);
1551 static inline struct shash_desc *ubifs_hash_get_desc(const struct ubifs_info *c)
1552 {
1553 	return ubifs_authenticated(c) ? __ubifs_hash_get_desc(c) : NULL;
1554 }
1555 
1556 static inline int ubifs_shash_init(const struct ubifs_info *c,
1557 				   struct shash_desc *desc)
1558 {
1559 	if (ubifs_authenticated(c))
1560 		return crypto_shash_init(desc);
1561 	else
1562 		return 0;
1563 }
1564 
1565 static inline int ubifs_shash_update(const struct ubifs_info *c,
1566 				      struct shash_desc *desc, const void *buf,
1567 				      unsigned int len)
1568 {
1569 	int err = 0;
1570 
1571 	if (ubifs_authenticated(c)) {
1572 		err = crypto_shash_update(desc, buf, len);
1573 		if (err < 0)
1574 			return err;
1575 	}
1576 
1577 	return 0;
1578 }
1579 
1580 static inline int ubifs_shash_final(const struct ubifs_info *c,
1581 				    struct shash_desc *desc, u8 *out)
1582 {
1583 	return ubifs_authenticated(c) ? crypto_shash_final(desc, out) : 0;
1584 }
1585 
1586 int __ubifs_node_calc_hash(const struct ubifs_info *c, const void *buf,
1587 			  u8 *hash);
1588 static inline int ubifs_node_calc_hash(const struct ubifs_info *c,
1589 					const void *buf, u8 *hash)
1590 {
1591 	if (ubifs_authenticated(c))
1592 		return __ubifs_node_calc_hash(c, buf, hash);
1593 	else
1594 		return 0;
1595 }
1596 
1597 int ubifs_prepare_auth_node(struct ubifs_info *c, void *node,
1598 			     struct shash_desc *inhash);
1599 
1600 /**
1601  * ubifs_check_hash - compare two hashes
1602  * @c: UBIFS file-system description object
1603  * @expected: first hash
1604  * @got: second hash
1605  *
1606  * Compare two hashes @expected and @got. Returns 0 when they are equal, a
1607  * negative error code otherwise.
1608  */
1609 static inline int ubifs_check_hash(const struct ubifs_info *c,
1610 				   const u8 *expected, const u8 *got)
1611 {
1612 	return crypto_memneq(expected, got, c->hash_len);
1613 }
1614 
1615 /**
1616  * ubifs_check_hmac - compare two HMACs
1617  * @c: UBIFS file-system description object
1618  * @expected: first HMAC
1619  * @got: second HMAC
1620  *
1621  * Compare two hashes @expected and @got. Returns 0 when they are equal, a
1622  * negative error code otherwise.
1623  */
1624 static inline int ubifs_check_hmac(const struct ubifs_info *c,
1625 				   const u8 *expected, const u8 *got)
1626 {
1627 	return crypto_memneq(expected, got, c->hmac_desc_len);
1628 }
1629 
1630 #ifdef CONFIG_UBIFS_FS_AUTHENTICATION
1631 void ubifs_bad_hash(const struct ubifs_info *c, const void *node,
1632 		    const u8 *hash, int lnum, int offs);
1633 #else
1634 static inline void ubifs_bad_hash(const struct ubifs_info *c, const void *node,
1635 				  const u8 *hash, int lnum, int offs) {};
1636 #endif
1637 
1638 int __ubifs_node_check_hash(const struct ubifs_info *c, const void *buf,
1639 			  const u8 *expected);
1640 static inline int ubifs_node_check_hash(const struct ubifs_info *c,
1641 					const void *buf, const u8 *expected)
1642 {
1643 	if (ubifs_authenticated(c))
1644 		return __ubifs_node_check_hash(c, buf, expected);
1645 	else
1646 		return 0;
1647 }
1648 
1649 int ubifs_init_authentication(struct ubifs_info *c);
1650 void __ubifs_exit_authentication(struct ubifs_info *c);
1651 static inline void ubifs_exit_authentication(struct ubifs_info *c)
1652 {
1653 	if (ubifs_authenticated(c))
1654 		__ubifs_exit_authentication(c);
1655 }
1656 
1657 /**
1658  * ubifs_branch_hash - returns a pointer to the hash of a branch
1659  * @c: UBIFS file-system description object
1660  * @br: branch to get the hash from
1661  *
1662  * This returns a pointer to the hash of a branch. Since the key already is a
1663  * dynamically sized object we cannot use a struct member here.
1664  */
1665 static inline u8 *ubifs_branch_hash(struct ubifs_info *c,
1666 				    struct ubifs_branch *br)
1667 {
1668 	return (void *)br + sizeof(*br) + c->key_len;
1669 }
1670 
1671 /**
1672  * ubifs_copy_hash - copy a hash
1673  * @c: UBIFS file-system description object
1674  * @from: source hash
1675  * @to: destination hash
1676  *
1677  * With authentication this copies a hash, otherwise does nothing.
1678  */
1679 static inline void ubifs_copy_hash(const struct ubifs_info *c, const u8 *from,
1680 				   u8 *to)
1681 {
1682 	if (ubifs_authenticated(c))
1683 		memcpy(to, from, c->hash_len);
1684 }
1685 
1686 int __ubifs_node_insert_hmac(const struct ubifs_info *c, void *buf,
1687 			      int len, int ofs_hmac);
1688 static inline int ubifs_node_insert_hmac(const struct ubifs_info *c, void *buf,
1689 					  int len, int ofs_hmac)
1690 {
1691 	if (ubifs_authenticated(c))
1692 		return __ubifs_node_insert_hmac(c, buf, len, ofs_hmac);
1693 	else
1694 		return 0;
1695 }
1696 
1697 int __ubifs_node_verify_hmac(const struct ubifs_info *c, const void *buf,
1698 			     int len, int ofs_hmac);
1699 static inline int ubifs_node_verify_hmac(const struct ubifs_info *c,
1700 					 const void *buf, int len, int ofs_hmac)
1701 {
1702 	if (ubifs_authenticated(c))
1703 		return __ubifs_node_verify_hmac(c, buf, len, ofs_hmac);
1704 	else
1705 		return 0;
1706 }
1707 
1708 /**
1709  * ubifs_auth_node_sz - returns the size of an authentication node
1710  * @c: UBIFS file-system description object
1711  *
1712  * This function returns the size of an authentication node which can
1713  * be 0 for unauthenticated filesystems or the real size of an auth node
1714  * authentication is enabled.
1715  */
1716 static inline int ubifs_auth_node_sz(const struct ubifs_info *c)
1717 {
1718 	if (ubifs_authenticated(c))
1719 		return sizeof(struct ubifs_auth_node) + c->hmac_desc_len;
1720 	else
1721 		return 0;
1722 }
1723 int ubifs_sb_verify_signature(struct ubifs_info *c,
1724 			      const struct ubifs_sb_node *sup);
1725 bool ubifs_hmac_zero(struct ubifs_info *c, const u8 *hmac);
1726 
1727 int ubifs_hmac_wkm(struct ubifs_info *c, u8 *hmac);
1728 
1729 int __ubifs_shash_copy_state(const struct ubifs_info *c, struct shash_desc *src,
1730 			     struct shash_desc *target);
1731 static inline int ubifs_shash_copy_state(const struct ubifs_info *c,
1732 					   struct shash_desc *src,
1733 					   struct shash_desc *target)
1734 {
1735 	if (ubifs_authenticated(c))
1736 		return __ubifs_shash_copy_state(c, src, target);
1737 	else
1738 		return 0;
1739 }
1740 
1741 /* io.c */
1742 void ubifs_ro_mode(struct ubifs_info *c, int err);
1743 int ubifs_leb_read(const struct ubifs_info *c, int lnum, void *buf, int offs,
1744 		   int len, int even_ebadmsg);
1745 int ubifs_leb_write(struct ubifs_info *c, int lnum, const void *buf, int offs,
1746 		    int len);
1747 int ubifs_leb_change(struct ubifs_info *c, int lnum, const void *buf, int len);
1748 int ubifs_leb_unmap(struct ubifs_info *c, int lnum);
1749 int ubifs_leb_map(struct ubifs_info *c, int lnum);
1750 int ubifs_is_mapped(const struct ubifs_info *c, int lnum);
1751 int ubifs_wbuf_write_nolock(struct ubifs_wbuf *wbuf, void *buf, int len);
1752 int ubifs_wbuf_seek_nolock(struct ubifs_wbuf *wbuf, int lnum, int offs);
1753 int ubifs_wbuf_init(struct ubifs_info *c, struct ubifs_wbuf *wbuf);
1754 int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len,
1755 		    int lnum, int offs);
1756 int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len,
1757 			 int lnum, int offs);
1758 int ubifs_write_node(struct ubifs_info *c, void *node, int len, int lnum,
1759 		     int offs);
1760 int ubifs_write_node_hmac(struct ubifs_info *c, void *buf, int len, int lnum,
1761 			  int offs, int hmac_offs);
1762 int ubifs_check_node(const struct ubifs_info *c, const void *buf, int len,
1763 		     int lnum, int offs, int quiet, int must_chk_crc);
1764 void ubifs_init_node(struct ubifs_info *c, void *buf, int len, int pad);
1765 void ubifs_crc_node(struct ubifs_info *c, void *buf, int len);
1766 void ubifs_prepare_node(struct ubifs_info *c, void *buf, int len, int pad);
1767 int ubifs_prepare_node_hmac(struct ubifs_info *c, void *node, int len,
1768 			    int hmac_offs, int pad);
1769 void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last);
1770 int ubifs_io_init(struct ubifs_info *c);
1771 void ubifs_pad(const struct ubifs_info *c, void *buf, int pad);
1772 int ubifs_wbuf_sync_nolock(struct ubifs_wbuf *wbuf);
1773 int ubifs_bg_wbufs_sync(struct ubifs_info *c);
1774 void ubifs_wbuf_add_ino_nolock(struct ubifs_wbuf *wbuf, ino_t inum);
1775 int ubifs_sync_wbufs_by_inode(struct ubifs_info *c, struct inode *inode);
1776 
1777 /* scan.c */
1778 struct ubifs_scan_leb *ubifs_scan(const struct ubifs_info *c, int lnum,
1779 				  int offs, void *sbuf, int quiet);
1780 void ubifs_scan_destroy(struct ubifs_scan_leb *sleb);
1781 int ubifs_scan_a_node(const struct ubifs_info *c, void *buf, int len, int lnum,
1782 		      int offs, int quiet);
1783 struct ubifs_scan_leb *ubifs_start_scan(const struct ubifs_info *c, int lnum,
1784 					int offs, void *sbuf);
1785 void ubifs_end_scan(const struct ubifs_info *c, struct ubifs_scan_leb *sleb,
1786 		    int lnum, int offs);
1787 int ubifs_add_snod(const struct ubifs_info *c, struct ubifs_scan_leb *sleb,
1788 		   void *buf, int offs);
1789 void ubifs_scanned_corruption(const struct ubifs_info *c, int lnum, int offs,
1790 			      void *buf);
1791 
1792 /* log.c */
1793 void ubifs_add_bud(struct ubifs_info *c, struct ubifs_bud *bud);
1794 void ubifs_create_buds_lists(struct ubifs_info *c);
1795 int ubifs_add_bud_to_log(struct ubifs_info *c, int jhead, int lnum, int offs);
1796 struct ubifs_bud *ubifs_search_bud(struct ubifs_info *c, int lnum);
1797 struct ubifs_wbuf *ubifs_get_wbuf(struct ubifs_info *c, int lnum);
1798 int ubifs_log_start_commit(struct ubifs_info *c, int *ltail_lnum);
1799 int ubifs_log_end_commit(struct ubifs_info *c, int new_ltail_lnum);
1800 int ubifs_log_post_commit(struct ubifs_info *c, int old_ltail_lnum);
1801 int ubifs_consolidate_log(struct ubifs_info *c);
1802 
1803 /* journal.c */
1804 int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir,
1805 		     const struct fscrypt_name *nm, const struct inode *inode,
1806 		     int deletion, int xent);
1807 int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
1808 			 const union ubifs_key *key, const void *buf, int len);
1809 int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode);
1810 int ubifs_jnl_delete_inode(struct ubifs_info *c, const struct inode *inode);
1811 int ubifs_jnl_xrename(struct ubifs_info *c, const struct inode *fst_dir,
1812 		      const struct inode *fst_inode,
1813 		      const struct fscrypt_name *fst_nm,
1814 		      const struct inode *snd_dir,
1815 		      const struct inode *snd_inode,
1816 		      const struct fscrypt_name *snd_nm, int sync);
1817 int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
1818 		     const struct inode *old_inode,
1819 		     const struct fscrypt_name *old_nm,
1820 		     const struct inode *new_dir,
1821 		     const struct inode *new_inode,
1822 		     const struct fscrypt_name *new_nm,
1823 		     const struct inode *whiteout, int sync);
1824 int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode,
1825 		       loff_t old_size, loff_t new_size);
1826 int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host,
1827 			   const struct inode *inode, const struct fscrypt_name *nm);
1828 int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode1,
1829 			   const struct inode *inode2);
1830 
1831 /* budget.c */
1832 int ubifs_budget_space(struct ubifs_info *c, struct ubifs_budget_req *req);
1833 void ubifs_release_budget(struct ubifs_info *c, struct ubifs_budget_req *req);
1834 void ubifs_release_dirty_inode_budget(struct ubifs_info *c,
1835 				      struct ubifs_inode *ui);
1836 int ubifs_budget_inode_op(struct ubifs_info *c, struct inode *inode,
1837 			  struct ubifs_budget_req *req);
1838 void ubifs_release_ino_dirty(struct ubifs_info *c, struct inode *inode,
1839 				struct ubifs_budget_req *req);
1840 void ubifs_cancel_ino_op(struct ubifs_info *c, struct inode *inode,
1841 			 struct ubifs_budget_req *req);
1842 long long ubifs_get_free_space(struct ubifs_info *c);
1843 long long ubifs_get_free_space_nolock(struct ubifs_info *c);
1844 int ubifs_calc_min_idx_lebs(struct ubifs_info *c);
1845 void ubifs_convert_page_budget(struct ubifs_info *c);
1846 long long ubifs_reported_space(const struct ubifs_info *c, long long free);
1847 long long ubifs_calc_available(const struct ubifs_info *c, int min_idx_lebs);
1848 
1849 /* find.c */
1850 int ubifs_find_free_space(struct ubifs_info *c, int min_space, int *offs,
1851 			  int squeeze);
1852 int ubifs_find_free_leb_for_idx(struct ubifs_info *c);
1853 int ubifs_find_dirty_leb(struct ubifs_info *c, struct ubifs_lprops *ret_lp,
1854 			 int min_space, int pick_free);
1855 int ubifs_find_dirty_idx_leb(struct ubifs_info *c);
1856 int ubifs_save_dirty_idx_lnums(struct ubifs_info *c);
1857 
1858 /* tnc.c */
1859 int ubifs_lookup_level0(struct ubifs_info *c, const union ubifs_key *key,
1860 			struct ubifs_znode **zn, int *n);
1861 int ubifs_tnc_lookup_nm(struct ubifs_info *c, const union ubifs_key *key,
1862 			void *node, const struct fscrypt_name *nm);
1863 int ubifs_tnc_lookup_dh(struct ubifs_info *c, const union ubifs_key *key,
1864 			void *node, uint32_t secondary_hash);
1865 int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key,
1866 		     void *node, int *lnum, int *offs);
1867 int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum,
1868 		  int offs, int len, const u8 *hash);
1869 int ubifs_tnc_replace(struct ubifs_info *c, const union ubifs_key *key,
1870 		      int old_lnum, int old_offs, int lnum, int offs, int len);
1871 int ubifs_tnc_add_nm(struct ubifs_info *c, const union ubifs_key *key,
1872 		     int lnum, int offs, int len, const u8 *hash,
1873 		     const struct fscrypt_name *nm);
1874 int ubifs_tnc_remove(struct ubifs_info *c, const union ubifs_key *key);
1875 int ubifs_tnc_remove_nm(struct ubifs_info *c, const union ubifs_key *key,
1876 			const struct fscrypt_name *nm);
1877 int ubifs_tnc_remove_dh(struct ubifs_info *c, const union ubifs_key *key,
1878 			uint32_t cookie);
1879 int ubifs_tnc_remove_range(struct ubifs_info *c, union ubifs_key *from_key,
1880 			   union ubifs_key *to_key);
1881 int ubifs_tnc_remove_ino(struct ubifs_info *c, ino_t inum);
1882 struct ubifs_dent_node *ubifs_tnc_next_ent(struct ubifs_info *c,
1883 					   union ubifs_key *key,
1884 					   const struct fscrypt_name *nm);
1885 void ubifs_tnc_close(struct ubifs_info *c);
1886 int ubifs_tnc_has_node(struct ubifs_info *c, union ubifs_key *key, int level,
1887 		       int lnum, int offs, int is_idx);
1888 int ubifs_dirty_idx_node(struct ubifs_info *c, union ubifs_key *key, int level,
1889 			 int lnum, int offs);
1890 /* Shared by tnc.c for tnc_commit.c */
1891 void destroy_old_idx(struct ubifs_info *c);
1892 int is_idx_node_in_tnc(struct ubifs_info *c, union ubifs_key *key, int level,
1893 		       int lnum, int offs);
1894 int insert_old_idx_znode(struct ubifs_info *c, struct ubifs_znode *znode);
1895 int ubifs_tnc_get_bu_keys(struct ubifs_info *c, struct bu_info *bu);
1896 int ubifs_tnc_bulk_read(struct ubifs_info *c, struct bu_info *bu);
1897 
1898 /* tnc_misc.c */
1899 struct ubifs_znode *ubifs_tnc_levelorder_next(const struct ubifs_info *c,
1900 					      struct ubifs_znode *zr,
1901 					      struct ubifs_znode *znode);
1902 int ubifs_search_zbranch(const struct ubifs_info *c,
1903 			 const struct ubifs_znode *znode,
1904 			 const union ubifs_key *key, int *n);
1905 struct ubifs_znode *ubifs_tnc_postorder_first(struct ubifs_znode *znode);
1906 struct ubifs_znode *ubifs_tnc_postorder_next(const struct ubifs_info *c,
1907 					     struct ubifs_znode *znode);
1908 long ubifs_destroy_tnc_subtree(const struct ubifs_info *c,
1909 			       struct ubifs_znode *zr);
1910 void ubifs_destroy_tnc_tree(struct ubifs_info *c);
1911 struct ubifs_znode *ubifs_load_znode(struct ubifs_info *c,
1912 				     struct ubifs_zbranch *zbr,
1913 				     struct ubifs_znode *parent, int iip);
1914 int ubifs_tnc_read_node(struct ubifs_info *c, struct ubifs_zbranch *zbr,
1915 			void *node);
1916 
1917 /* tnc_commit.c */
1918 int ubifs_tnc_start_commit(struct ubifs_info *c, struct ubifs_zbranch *zroot);
1919 int ubifs_tnc_end_commit(struct ubifs_info *c);
1920 
1921 /* shrinker.c */
1922 unsigned long ubifs_shrink_scan(struct shrinker *shrink,
1923 				struct shrink_control *sc);
1924 unsigned long ubifs_shrink_count(struct shrinker *shrink,
1925 				 struct shrink_control *sc);
1926 
1927 /* commit.c */
1928 int ubifs_bg_thread(void *info);
1929 void ubifs_commit_required(struct ubifs_info *c);
1930 void ubifs_request_bg_commit(struct ubifs_info *c);
1931 int ubifs_run_commit(struct ubifs_info *c);
1932 void ubifs_recovery_commit(struct ubifs_info *c);
1933 int ubifs_gc_should_commit(struct ubifs_info *c);
1934 void ubifs_wait_for_commit(struct ubifs_info *c);
1935 
1936 /* master.c */
1937 int ubifs_compare_master_node(struct ubifs_info *c, void *m1, void *m2);
1938 int ubifs_read_master(struct ubifs_info *c);
1939 int ubifs_write_master(struct ubifs_info *c);
1940 
1941 /* sb.c */
1942 int ubifs_read_superblock(struct ubifs_info *c);
1943 int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup);
1944 int ubifs_fixup_free_space(struct ubifs_info *c);
1945 int ubifs_enable_encryption(struct ubifs_info *c);
1946 
1947 /* replay.c */
1948 int ubifs_validate_entry(struct ubifs_info *c,
1949 			 const struct ubifs_dent_node *dent);
1950 int ubifs_replay_journal(struct ubifs_info *c);
1951 
1952 /* gc.c */
1953 int ubifs_garbage_collect(struct ubifs_info *c, int anyway);
1954 int ubifs_gc_start_commit(struct ubifs_info *c);
1955 int ubifs_gc_end_commit(struct ubifs_info *c);
1956 void ubifs_destroy_idx_gc(struct ubifs_info *c);
1957 int ubifs_get_idx_gc_leb(struct ubifs_info *c);
1958 int ubifs_garbage_collect_leb(struct ubifs_info *c, struct ubifs_lprops *lp);
1959 
1960 /* orphan.c */
1961 int ubifs_add_orphan(struct ubifs_info *c, ino_t inum);
1962 void ubifs_delete_orphan(struct ubifs_info *c, ino_t inum);
1963 int ubifs_orphan_start_commit(struct ubifs_info *c);
1964 int ubifs_orphan_end_commit(struct ubifs_info *c);
1965 int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only);
1966 int ubifs_clear_orphans(struct ubifs_info *c);
1967 
1968 /* lpt.c */
1969 int ubifs_calc_lpt_geom(struct ubifs_info *c);
1970 int ubifs_create_dflt_lpt(struct ubifs_info *c, int *main_lebs, int lpt_first,
1971 			  int *lpt_lebs, int *big_lpt, u8 *hash);
1972 int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr);
1973 struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum);
1974 struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum);
1975 int ubifs_lpt_scan_nolock(struct ubifs_info *c, int start_lnum, int end_lnum,
1976 			  ubifs_lpt_scan_callback scan_cb, void *data);
1977 
1978 /* Shared by lpt.c for lpt_commit.c */
1979 void ubifs_pack_lsave(struct ubifs_info *c, void *buf, int *lsave);
1980 void ubifs_pack_ltab(struct ubifs_info *c, void *buf,
1981 		     struct ubifs_lpt_lprops *ltab);
1982 void ubifs_pack_pnode(struct ubifs_info *c, void *buf,
1983 		      struct ubifs_pnode *pnode);
1984 void ubifs_pack_nnode(struct ubifs_info *c, void *buf,
1985 		      struct ubifs_nnode *nnode);
1986 struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c,
1987 				    struct ubifs_nnode *parent, int iip);
1988 struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c,
1989 				    struct ubifs_nnode *parent, int iip);
1990 struct ubifs_pnode *ubifs_pnode_lookup(struct ubifs_info *c, int i);
1991 int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip);
1992 void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty);
1993 void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode);
1994 uint32_t ubifs_unpack_bits(const struct ubifs_info *c, uint8_t **addr, int *pos, int nrbits);
1995 struct ubifs_nnode *ubifs_first_nnode(struct ubifs_info *c, int *hght);
1996 /* Needed only in debugging code in lpt_commit.c */
1997 int ubifs_unpack_nnode(const struct ubifs_info *c, void *buf,
1998 		       struct ubifs_nnode *nnode);
1999 int ubifs_lpt_calc_hash(struct ubifs_info *c, u8 *hash);
2000 
2001 /* lpt_commit.c */
2002 int ubifs_lpt_start_commit(struct ubifs_info *c);
2003 int ubifs_lpt_end_commit(struct ubifs_info *c);
2004 int ubifs_lpt_post_commit(struct ubifs_info *c);
2005 void ubifs_lpt_free(struct ubifs_info *c, int wr_only);
2006 
2007 /* lprops.c */
2008 const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
2009 					   const struct ubifs_lprops *lp,
2010 					   int free, int dirty, int flags,
2011 					   int idx_gc_cnt);
2012 void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst);
2013 void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
2014 		      int cat);
2015 void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
2016 		       struct ubifs_lprops *new_lprops);
2017 void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops);
2018 int ubifs_categorize_lprops(const struct ubifs_info *c,
2019 			    const struct ubifs_lprops *lprops);
2020 int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
2021 			int flags_set, int flags_clean, int idx_gc_cnt);
2022 int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
2023 			int flags_set, int flags_clean);
2024 int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp);
2025 const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c);
2026 const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c);
2027 const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c);
2028 const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c);
2029 int ubifs_calc_dark(const struct ubifs_info *c, int spc);
2030 
2031 /* file.c */
2032 int ubifs_fsync(struct file *file, loff_t start, loff_t end, int datasync);
2033 int ubifs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
2034 		  struct iattr *attr);
2035 int ubifs_update_time(struct inode *inode, int flags);
2036 
2037 /* dir.c */
2038 struct inode *ubifs_new_inode(struct ubifs_info *c, struct inode *dir,
2039 			      umode_t mode, bool is_xattr);
2040 int ubifs_getattr(struct mnt_idmap *idmap, const struct path *path,
2041 		  struct kstat *stat, u32 request_mask, unsigned int flags);
2042 int ubifs_check_dir_empty(struct inode *dir);
2043 
2044 /* xattr.c */
2045 int ubifs_xattr_set(struct inode *host, const char *name, const void *value,
2046 		    size_t size, int flags, bool check_lock);
2047 ssize_t ubifs_xattr_get(struct inode *host, const char *name, void *buf,
2048 			size_t size);
2049 
2050 #ifdef CONFIG_UBIFS_FS_XATTR
2051 extern const struct xattr_handler * const ubifs_xattr_handlers[];
2052 ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size);
2053 void ubifs_evict_xattr_inode(struct ubifs_info *c, ino_t xattr_inum);
2054 int ubifs_purge_xattrs(struct inode *host);
2055 #else
2056 #define ubifs_listxattr NULL
2057 #define ubifs_xattr_handlers NULL
2058 static inline void ubifs_evict_xattr_inode(struct ubifs_info *c,
2059 					   ino_t xattr_inum) { }
2060 static inline int ubifs_purge_xattrs(struct inode *host)
2061 {
2062 	return 0;
2063 }
2064 #endif
2065 
2066 #ifdef CONFIG_UBIFS_FS_SECURITY
2067 extern int ubifs_init_security(struct inode *dentry, struct inode *inode,
2068 			const struct qstr *qstr);
2069 #else
2070 static inline int ubifs_init_security(struct inode *dentry,
2071 			struct inode *inode, const struct qstr *qstr)
2072 {
2073 	return 0;
2074 }
2075 #endif
2076 
2077 
2078 /* super.c */
2079 struct inode *ubifs_iget(struct super_block *sb, unsigned long inum);
2080 
2081 /* recovery.c */
2082 int ubifs_recover_master_node(struct ubifs_info *c);
2083 int ubifs_write_rcvrd_mst_node(struct ubifs_info *c);
2084 struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
2085 					 int offs, void *sbuf, int jhead);
2086 struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum,
2087 					     int offs, void *sbuf);
2088 int ubifs_recover_inl_heads(struct ubifs_info *c, void *sbuf);
2089 int ubifs_clean_lebs(struct ubifs_info *c, void *sbuf);
2090 int ubifs_rcvry_gc_commit(struct ubifs_info *c);
2091 int ubifs_recover_size_accum(struct ubifs_info *c, union ubifs_key *key,
2092 			     int deletion, loff_t new_size);
2093 int ubifs_recover_size(struct ubifs_info *c, bool in_place);
2094 void ubifs_destroy_size_tree(struct ubifs_info *c);
2095 
2096 /* ioctl.c */
2097 int ubifs_fileattr_get(struct dentry *dentry, struct fileattr *fa);
2098 int ubifs_fileattr_set(struct mnt_idmap *idmap,
2099 		       struct dentry *dentry, struct fileattr *fa);
2100 long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
2101 void ubifs_set_inode_flags(struct inode *inode);
2102 #ifdef CONFIG_COMPAT
2103 long ubifs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
2104 #endif
2105 
2106 /* compressor.c */
2107 int __init ubifs_compressors_init(void);
2108 void ubifs_compressors_exit(void);
2109 void ubifs_compress(const struct ubifs_info *c, const void *in_buf, int in_len,
2110 		    void *out_buf, int *out_len, int *compr_type);
2111 int ubifs_decompress(const struct ubifs_info *c, const void *buf, int len,
2112 		     void *out, int *out_len, int compr_type);
2113 
2114 /* sysfs.c */
2115 int ubifs_sysfs_init(void);
2116 void ubifs_sysfs_exit(void);
2117 int ubifs_sysfs_register(struct ubifs_info *c);
2118 void ubifs_sysfs_unregister(struct ubifs_info *c);
2119 
2120 #include "debug.h"
2121 #include "misc.h"
2122 #include "key.h"
2123 
2124 #ifndef CONFIG_FS_ENCRYPTION
2125 static inline int ubifs_encrypt(const struct inode *inode,
2126 				struct ubifs_data_node *dn,
2127 				unsigned int in_len, unsigned int *out_len,
2128 				int block)
2129 {
2130 	struct ubifs_info *c = inode->i_sb->s_fs_info;
2131 	ubifs_assert(c, 0);
2132 	return -EOPNOTSUPP;
2133 }
2134 static inline int ubifs_decrypt(const struct inode *inode,
2135 				struct ubifs_data_node *dn,
2136 				unsigned int *out_len, int block)
2137 {
2138 	struct ubifs_info *c = inode->i_sb->s_fs_info;
2139 	ubifs_assert(c, 0);
2140 	return -EOPNOTSUPP;
2141 }
2142 #else
2143 /* crypto.c */
2144 int ubifs_encrypt(const struct inode *inode, struct ubifs_data_node *dn,
2145 		  unsigned int in_len, unsigned int *out_len, int block);
2146 int ubifs_decrypt(const struct inode *inode, struct ubifs_data_node *dn,
2147 		  unsigned int *out_len, int block);
2148 #endif
2149 
2150 extern const struct fscrypt_operations ubifs_crypt_operations;
2151 
2152 /* Normal UBIFS messages */
2153 __printf(2, 3)
2154 void ubifs_msg(const struct ubifs_info *c, const char *fmt, ...);
2155 __printf(2, 3)
2156 void ubifs_err(const struct ubifs_info *c, const char *fmt, ...);
2157 __printf(2, 3)
2158 void ubifs_warn(const struct ubifs_info *c, const char *fmt, ...);
2159 /*
2160  * A conditional variant of 'ubifs_err()' which doesn't output anything
2161  * if probing (ie. SB_SILENT set).
2162  */
2163 #define ubifs_errc(c, fmt, ...)						\
2164 do {									\
2165 	if (!(c)->probing)						\
2166 		ubifs_err(c, fmt, ##__VA_ARGS__);			\
2167 } while (0)
2168 
2169 #endif /* !__UBIFS_H__ */
2170