xref: /openbmc/linux/fs/ubifs/ubifs.h (revision 0661cb2a)
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 <crypto/hash_info.h>
31 #include <crypto/hash.h>
32 #include <crypto/algapi.h>
33 
34 #include <linux/fscrypt.h>
35 
36 #include "ubifs-media.h"
37 
38 /* Version of this UBIFS implementation */
39 #define UBIFS_VERSION 1
40 
41 /* UBIFS file system VFS magic number */
42 #define UBIFS_SUPER_MAGIC 0x24051905
43 
44 /* Number of UBIFS blocks per VFS page */
45 #define UBIFS_BLOCKS_PER_PAGE (PAGE_SIZE / UBIFS_BLOCK_SIZE)
46 #define UBIFS_BLOCKS_PER_PAGE_SHIFT (PAGE_SHIFT - UBIFS_BLOCK_SHIFT)
47 
48 /* "File system end of life" sequence number watermark */
49 #define SQNUM_WARN_WATERMARK 0xFFFFFFFF00000000ULL
50 #define SQNUM_WATERMARK      0xFFFFFFFFFF000000ULL
51 
52 /*
53  * Minimum amount of LEBs reserved for the index. At present the index needs at
54  * least 2 LEBs: one for the index head and one for in-the-gaps method (which
55  * currently does not cater for the index head and so excludes it from
56  * consideration).
57  */
58 #define MIN_INDEX_LEBS 2
59 
60 /* Minimum amount of data UBIFS writes to the flash */
61 #define MIN_WRITE_SZ (UBIFS_DATA_NODE_SZ + 8)
62 
63 /*
64  * Currently we do not support inode number overlapping and re-using, so this
65  * watermark defines dangerous inode number level. This should be fixed later,
66  * although it is difficult to exceed current limit. Another option is to use
67  * 64-bit inode numbers, but this means more overhead.
68  */
69 #define INUM_WARN_WATERMARK 0xFFF00000
70 #define INUM_WATERMARK      0xFFFFFF00
71 
72 /* Maximum number of entries in each LPT (LEB category) heap */
73 #define LPT_HEAP_SZ 256
74 
75 /*
76  * Background thread name pattern. The numbers are UBI device and volume
77  * numbers.
78  */
79 #define BGT_NAME_PATTERN "ubifs_bgt%d_%d"
80 
81 /* Maximum possible inode number (only 32-bit inodes are supported now) */
82 #define MAX_INUM 0xFFFFFFFF
83 
84 /* Number of non-data journal heads */
85 #define NONDATA_JHEADS_CNT 2
86 
87 /* Shorter names for journal head numbers for internal usage */
88 #define GCHD   UBIFS_GC_HEAD
89 #define BASEHD UBIFS_BASE_HEAD
90 #define DATAHD UBIFS_DATA_HEAD
91 
92 /* 'No change' value for 'ubifs_change_lp()' */
93 #define LPROPS_NC 0x80000001
94 
95 /*
96  * There is no notion of truncation key because truncation nodes do not exist
97  * in TNC. However, when replaying, it is handy to introduce fake "truncation"
98  * keys for truncation nodes because the code becomes simpler. So we define
99  * %UBIFS_TRUN_KEY type.
100  *
101  * But otherwise, out of the journal reply scope, the truncation keys are
102  * invalid.
103  */
104 #define UBIFS_TRUN_KEY    UBIFS_KEY_TYPES_CNT
105 #define UBIFS_INVALID_KEY UBIFS_KEY_TYPES_CNT
106 
107 /*
108  * How much a directory entry/extended attribute entry adds to the parent/host
109  * inode.
110  */
111 #define CALC_DENT_SIZE(name_len) ALIGN(UBIFS_DENT_NODE_SZ + (name_len) + 1, 8)
112 
113 /* How much an extended attribute adds to the host inode */
114 #define CALC_XATTR_BYTES(data_len) ALIGN(UBIFS_INO_NODE_SZ + (data_len) + 1, 8)
115 
116 /*
117  * Znodes which were not touched for 'OLD_ZNODE_AGE' seconds are considered
118  * "old", and znode which were touched last 'YOUNG_ZNODE_AGE' seconds ago are
119  * considered "young". This is used by shrinker when selecting znode to trim
120  * off.
121  */
122 #define OLD_ZNODE_AGE 20
123 #define YOUNG_ZNODE_AGE 5
124 
125 /*
126  * Some compressors, like LZO, may end up with more data then the input buffer.
127  * So UBIFS always allocates larger output buffer, to be sure the compressor
128  * will not corrupt memory in case of worst case compression.
129  */
130 #define WORST_COMPR_FACTOR 2
131 
132 #ifdef CONFIG_FS_ENCRYPTION
133 #define UBIFS_CIPHER_BLOCK_SIZE FS_CRYPTO_BLOCK_SIZE
134 #else
135 #define UBIFS_CIPHER_BLOCK_SIZE 0
136 #endif
137 
138 /*
139  * How much memory is needed for a buffer where we compress a data node.
140  */
141 #define COMPRESSED_DATA_NODE_BUF_SZ \
142 	(UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE * WORST_COMPR_FACTOR)
143 
144 /* Maximum expected tree height for use by bottom_up_buf */
145 #define BOTTOM_UP_HEIGHT 64
146 
147 /* Maximum number of data nodes to bulk-read */
148 #define UBIFS_MAX_BULK_READ 32
149 
150 #ifdef CONFIG_UBIFS_FS_AUTHENTICATION
151 #define UBIFS_HASH_ARR_SZ UBIFS_MAX_HASH_LEN
152 #define UBIFS_HMAC_ARR_SZ UBIFS_MAX_HMAC_LEN
153 #else
154 #define UBIFS_HASH_ARR_SZ 0
155 #define UBIFS_HMAC_ARR_SZ 0
156 #endif
157 
158 /*
159  * Lockdep classes for UBIFS inode @ui_mutex.
160  */
161 enum {
162 	WB_MUTEX_1 = 0,
163 	WB_MUTEX_2 = 1,
164 	WB_MUTEX_3 = 2,
165 	WB_MUTEX_4 = 3,
166 };
167 
168 /*
169  * Znode flags (actually, bit numbers which store the flags).
170  *
171  * DIRTY_ZNODE: znode is dirty
172  * COW_ZNODE: znode is being committed and a new instance of this znode has to
173  *            be created before changing this znode
174  * OBSOLETE_ZNODE: znode is obsolete, which means it was deleted, but it is
175  *                 still in the commit list and the ongoing commit operation
176  *                 will commit it, and delete this znode after it is done
177  */
178 enum {
179 	DIRTY_ZNODE    = 0,
180 	COW_ZNODE      = 1,
181 	OBSOLETE_ZNODE = 2,
182 };
183 
184 /*
185  * Commit states.
186  *
187  * COMMIT_RESTING: commit is not wanted
188  * COMMIT_BACKGROUND: background commit has been requested
189  * COMMIT_REQUIRED: commit is required
190  * COMMIT_RUNNING_BACKGROUND: background commit is running
191  * COMMIT_RUNNING_REQUIRED: commit is running and it is required
192  * COMMIT_BROKEN: commit failed
193  */
194 enum {
195 	COMMIT_RESTING = 0,
196 	COMMIT_BACKGROUND,
197 	COMMIT_REQUIRED,
198 	COMMIT_RUNNING_BACKGROUND,
199 	COMMIT_RUNNING_REQUIRED,
200 	COMMIT_BROKEN,
201 };
202 
203 /*
204  * 'ubifs_scan_a_node()' return values.
205  *
206  * SCANNED_GARBAGE:  scanned garbage
207  * SCANNED_EMPTY_SPACE: scanned empty space
208  * SCANNED_A_NODE: scanned a valid node
209  * SCANNED_A_CORRUPT_NODE: scanned a corrupted node
210  * SCANNED_A_BAD_PAD_NODE: scanned a padding node with invalid pad length
211  *
212  * Greater than zero means: 'scanned that number of padding bytes'
213  */
214 enum {
215 	SCANNED_GARBAGE        = 0,
216 	SCANNED_EMPTY_SPACE    = -1,
217 	SCANNED_A_NODE         = -2,
218 	SCANNED_A_CORRUPT_NODE = -3,
219 	SCANNED_A_BAD_PAD_NODE = -4,
220 };
221 
222 /*
223  * LPT cnode flag bits.
224  *
225  * DIRTY_CNODE: cnode is dirty
226  * OBSOLETE_CNODE: cnode is being committed and has been copied (or deleted),
227  *                 so it can (and must) be freed when the commit is finished
228  * COW_CNODE: cnode is being committed and must be copied before writing
229  */
230 enum {
231 	DIRTY_CNODE    = 0,
232 	OBSOLETE_CNODE = 1,
233 	COW_CNODE      = 2,
234 };
235 
236 /*
237  * Dirty flag bits (lpt_drty_flgs) for LPT special nodes.
238  *
239  * LTAB_DIRTY: ltab node is dirty
240  * LSAVE_DIRTY: lsave node is dirty
241  */
242 enum {
243 	LTAB_DIRTY  = 1,
244 	LSAVE_DIRTY = 2,
245 };
246 
247 /*
248  * Return codes used by the garbage collector.
249  * @LEB_FREED: the logical eraseblock was freed and is ready to use
250  * @LEB_FREED_IDX: indexing LEB was freed and can be used only after the commit
251  * @LEB_RETAINED: the logical eraseblock was freed and retained for GC purposes
252  */
253 enum {
254 	LEB_FREED,
255 	LEB_FREED_IDX,
256 	LEB_RETAINED,
257 };
258 
259 /*
260  * Action taken upon a failed ubifs_assert().
261  * @ASSACT_REPORT: just report the failed assertion
262  * @ASSACT_RO: switch to read-only mode
263  * @ASSACT_PANIC: call BUG() and possible panic the kernel
264  */
265 enum {
266 	ASSACT_REPORT = 0,
267 	ASSACT_RO,
268 	ASSACT_PANIC,
269 };
270 
271 /**
272  * struct ubifs_old_idx - index node obsoleted since last commit start.
273  * @rb: rb-tree node
274  * @lnum: LEB number of obsoleted index node
275  * @offs: offset of obsoleted index node
276  */
277 struct ubifs_old_idx {
278 	struct rb_node rb;
279 	int lnum;
280 	int offs;
281 };
282 
283 /* The below union makes it easier to deal with keys */
284 union ubifs_key {
285 	uint8_t u8[UBIFS_SK_LEN];
286 	uint32_t u32[UBIFS_SK_LEN/4];
287 	uint64_t u64[UBIFS_SK_LEN/8];
288 	__le32 j32[UBIFS_SK_LEN/4];
289 };
290 
291 /**
292  * struct ubifs_scan_node - UBIFS scanned node information.
293  * @list: list of scanned nodes
294  * @key: key of node scanned (if it has one)
295  * @sqnum: sequence number
296  * @type: type of node scanned
297  * @offs: offset with LEB of node scanned
298  * @len: length of node scanned
299  * @node: raw node
300  */
301 struct ubifs_scan_node {
302 	struct list_head list;
303 	union ubifs_key key;
304 	unsigned long long sqnum;
305 	int type;
306 	int offs;
307 	int len;
308 	void *node;
309 };
310 
311 /**
312  * struct ubifs_scan_leb - UBIFS scanned LEB information.
313  * @lnum: logical eraseblock number
314  * @nodes_cnt: number of nodes scanned
315  * @nodes: list of struct ubifs_scan_node
316  * @endpt: end point (and therefore the start of empty space)
317  * @buf: buffer containing entire LEB scanned
318  */
319 struct ubifs_scan_leb {
320 	int lnum;
321 	int nodes_cnt;
322 	struct list_head nodes;
323 	int endpt;
324 	void *buf;
325 };
326 
327 /**
328  * struct ubifs_gced_idx_leb - garbage-collected indexing LEB.
329  * @list: list
330  * @lnum: LEB number
331  * @unmap: OK to unmap this LEB
332  *
333  * This data structure is used to temporary store garbage-collected indexing
334  * LEBs - they are not released immediately, but only after the next commit.
335  * This is needed to guarantee recoverability.
336  */
337 struct ubifs_gced_idx_leb {
338 	struct list_head list;
339 	int lnum;
340 	int unmap;
341 };
342 
343 /**
344  * struct ubifs_inode - UBIFS in-memory inode description.
345  * @vfs_inode: VFS inode description object
346  * @creat_sqnum: sequence number at time of creation
347  * @del_cmtno: commit number corresponding to the time the inode was deleted,
348  *             protected by @c->commit_sem;
349  * @xattr_size: summarized size of all extended attributes in bytes
350  * @xattr_cnt: count of extended attributes this inode has
351  * @xattr_names: sum of lengths of all extended attribute names belonging to
352  *               this inode
353  * @dirty: non-zero if the inode is dirty
354  * @xattr: non-zero if this is an extended attribute inode
355  * @bulk_read: non-zero if bulk-read should be used
356  * @ui_mutex: serializes inode write-back with the rest of VFS operations,
357  *            serializes "clean <-> dirty" state changes, serializes bulk-read,
358  *            protects @dirty, @bulk_read, @ui_size, and @xattr_size
359  * @xattr_sem: serilizes write operations (remove|set|create) on xattr
360  * @ui_lock: protects @synced_i_size
361  * @synced_i_size: synchronized size of inode, i.e. the value of inode size
362  *                 currently stored on the flash; used only for regular file
363  *                 inodes
364  * @ui_size: inode size used by UBIFS when writing to flash
365  * @flags: inode flags (@UBIFS_COMPR_FL, etc)
366  * @compr_type: default compression type used for this inode
367  * @last_page_read: page number of last page read (for bulk read)
368  * @read_in_a_row: number of consecutive pages read in a row (for bulk read)
369  * @data_len: length of the data attached to the inode
370  * @data: inode's data
371  *
372  * @ui_mutex exists for two main reasons. At first it prevents inodes from
373  * being written back while UBIFS changing them, being in the middle of an VFS
374  * operation. This way UBIFS makes sure the inode fields are consistent. For
375  * example, in 'ubifs_rename()' we change 3 inodes simultaneously, and
376  * write-back must not write any of them before we have finished.
377  *
378  * The second reason is budgeting - UBIFS has to budget all operations. If an
379  * operation is going to mark an inode dirty, it has to allocate budget for
380  * this. It cannot just mark it dirty because there is no guarantee there will
381  * be enough flash space to write the inode back later. This means UBIFS has
382  * to have full control over inode "clean <-> dirty" transitions (and pages
383  * actually). But unfortunately, VFS marks inodes dirty in many places, and it
384  * does not ask the file-system if it is allowed to do so (there is a notifier,
385  * but it is not enough), i.e., there is no mechanism to synchronize with this.
386  * So UBIFS has its own inode dirty flag and its own mutex to serialize
387  * "clean <-> dirty" transitions.
388  *
389  * The @synced_i_size field is used to make sure we never write pages which are
390  * beyond last synchronized inode size. See 'ubifs_writepage()' for more
391  * information.
392  *
393  * The @ui_size is a "shadow" variable for @inode->i_size and UBIFS uses
394  * @ui_size instead of @inode->i_size. The reason for this is that UBIFS cannot
395  * make sure @inode->i_size is always changed under @ui_mutex, because it
396  * cannot call 'truncate_setsize()' with @ui_mutex locked, because it would
397  * deadlock with 'ubifs_writepage()' (see file.c). All the other inode fields
398  * are changed under @ui_mutex, so they do not need "shadow" fields. Note, one
399  * could consider to rework locking and base it on "shadow" fields.
400  */
401 struct ubifs_inode {
402 	struct inode vfs_inode;
403 	unsigned long long creat_sqnum;
404 	unsigned long long del_cmtno;
405 	unsigned int xattr_size;
406 	unsigned int xattr_cnt;
407 	unsigned int xattr_names;
408 	unsigned int dirty:1;
409 	unsigned int xattr:1;
410 	unsigned int bulk_read:1;
411 	unsigned int compr_type:2;
412 	struct mutex ui_mutex;
413 	struct rw_semaphore xattr_sem;
414 	spinlock_t ui_lock;
415 	loff_t synced_i_size;
416 	loff_t ui_size;
417 	int flags;
418 	pgoff_t last_page_read;
419 	pgoff_t read_in_a_row;
420 	int data_len;
421 	void *data;
422 };
423 
424 /**
425  * struct ubifs_unclean_leb - records a LEB recovered under read-only mode.
426  * @list: list
427  * @lnum: LEB number of recovered LEB
428  * @endpt: offset where recovery ended
429  *
430  * This structure records a LEB identified during recovery that needs to be
431  * cleaned but was not because UBIFS was mounted read-only. The information
432  * is used to clean the LEB when remounting to read-write mode.
433  */
434 struct ubifs_unclean_leb {
435 	struct list_head list;
436 	int lnum;
437 	int endpt;
438 };
439 
440 /*
441  * LEB properties flags.
442  *
443  * LPROPS_UNCAT: not categorized
444  * LPROPS_DIRTY: dirty > free, dirty >= @c->dead_wm, not index
445  * LPROPS_DIRTY_IDX: dirty + free > @c->min_idx_node_sze and index
446  * LPROPS_FREE: free > 0, dirty < @c->dead_wm, not empty, not index
447  * LPROPS_HEAP_CNT: number of heaps used for storing categorized LEBs
448  * LPROPS_EMPTY: LEB is empty, not taken
449  * LPROPS_FREEABLE: free + dirty == leb_size, not index, not taken
450  * LPROPS_FRDI_IDX: free + dirty == leb_size and index, may be taken
451  * LPROPS_CAT_MASK: mask for the LEB categories above
452  * LPROPS_TAKEN: LEB was taken (this flag is not saved on the media)
453  * LPROPS_INDEX: LEB contains indexing nodes (this flag also exists on flash)
454  */
455 enum {
456 	LPROPS_UNCAT     =  0,
457 	LPROPS_DIRTY     =  1,
458 	LPROPS_DIRTY_IDX =  2,
459 	LPROPS_FREE      =  3,
460 	LPROPS_HEAP_CNT  =  3,
461 	LPROPS_EMPTY     =  4,
462 	LPROPS_FREEABLE  =  5,
463 	LPROPS_FRDI_IDX  =  6,
464 	LPROPS_CAT_MASK  = 15,
465 	LPROPS_TAKEN     = 16,
466 	LPROPS_INDEX     = 32,
467 };
468 
469 /**
470  * struct ubifs_lprops - logical eraseblock properties.
471  * @free: amount of free space in bytes
472  * @dirty: amount of dirty space in bytes
473  * @flags: LEB properties flags (see above)
474  * @lnum: LEB number
475  * @list: list of same-category lprops (for LPROPS_EMPTY and LPROPS_FREEABLE)
476  * @hpos: heap position in heap of same-category lprops (other categories)
477  */
478 struct ubifs_lprops {
479 	int free;
480 	int dirty;
481 	int flags;
482 	int lnum;
483 	union {
484 		struct list_head list;
485 		int hpos;
486 	};
487 };
488 
489 /**
490  * struct ubifs_lpt_lprops - LPT logical eraseblock properties.
491  * @free: amount of free space in bytes
492  * @dirty: amount of dirty space in bytes
493  * @tgc: trivial GC flag (1 => unmap after commit end)
494  * @cmt: commit flag (1 => reserved for commit)
495  */
496 struct ubifs_lpt_lprops {
497 	int free;
498 	int dirty;
499 	unsigned tgc:1;
500 	unsigned cmt:1;
501 };
502 
503 /**
504  * struct ubifs_lp_stats - statistics of eraseblocks in the main area.
505  * @empty_lebs: number of empty LEBs
506  * @taken_empty_lebs: number of taken LEBs
507  * @idx_lebs: number of indexing LEBs
508  * @total_free: total free space in bytes (includes all LEBs)
509  * @total_dirty: total dirty space in bytes (includes all LEBs)
510  * @total_used: total used space in bytes (does not include index LEBs)
511  * @total_dead: total dead space in bytes (does not include index LEBs)
512  * @total_dark: total dark space in bytes (does not include index LEBs)
513  *
514  * The @taken_empty_lebs field counts the LEBs that are in the transient state
515  * of having been "taken" for use but not yet written to. @taken_empty_lebs is
516  * needed to account correctly for @gc_lnum, otherwise @empty_lebs could be
517  * used by itself (in which case 'unused_lebs' would be a better name). In the
518  * case of @gc_lnum, it is "taken" at mount time or whenever a LEB is retained
519  * by GC, but unlike other empty LEBs that are "taken", it may not be written
520  * straight away (i.e. before the next commit start or unmount), so either
521  * @gc_lnum must be specially accounted for, or the current approach followed
522  * i.e. count it under @taken_empty_lebs.
523  *
524  * @empty_lebs includes @taken_empty_lebs.
525  *
526  * @total_used, @total_dead and @total_dark fields do not account indexing
527  * LEBs.
528  */
529 struct ubifs_lp_stats {
530 	int empty_lebs;
531 	int taken_empty_lebs;
532 	int idx_lebs;
533 	long long total_free;
534 	long long total_dirty;
535 	long long total_used;
536 	long long total_dead;
537 	long long total_dark;
538 };
539 
540 struct ubifs_nnode;
541 
542 /**
543  * struct ubifs_cnode - LEB Properties Tree common node.
544  * @parent: parent nnode
545  * @cnext: next cnode to commit
546  * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE)
547  * @iip: index in parent
548  * @level: level in the tree (zero for pnodes, greater than zero for nnodes)
549  * @num: node number
550  */
551 struct ubifs_cnode {
552 	struct ubifs_nnode *parent;
553 	struct ubifs_cnode *cnext;
554 	unsigned long flags;
555 	int iip;
556 	int level;
557 	int num;
558 };
559 
560 /**
561  * struct ubifs_pnode - LEB Properties Tree leaf node.
562  * @parent: parent nnode
563  * @cnext: next cnode to commit
564  * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE)
565  * @iip: index in parent
566  * @level: level in the tree (always zero for pnodes)
567  * @num: node number
568  * @lprops: LEB properties array
569  */
570 struct ubifs_pnode {
571 	struct ubifs_nnode *parent;
572 	struct ubifs_cnode *cnext;
573 	unsigned long flags;
574 	int iip;
575 	int level;
576 	int num;
577 	struct ubifs_lprops lprops[UBIFS_LPT_FANOUT];
578 };
579 
580 /**
581  * struct ubifs_nbranch - LEB Properties Tree internal node branch.
582  * @lnum: LEB number of child
583  * @offs: offset of child
584  * @nnode: nnode child
585  * @pnode: pnode child
586  * @cnode: cnode child
587  */
588 struct ubifs_nbranch {
589 	int lnum;
590 	int offs;
591 	union {
592 		struct ubifs_nnode *nnode;
593 		struct ubifs_pnode *pnode;
594 		struct ubifs_cnode *cnode;
595 	};
596 };
597 
598 /**
599  * struct ubifs_nnode - LEB Properties Tree internal node.
600  * @parent: parent nnode
601  * @cnext: next cnode to commit
602  * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE)
603  * @iip: index in parent
604  * @level: level in the tree (always greater than zero for nnodes)
605  * @num: node number
606  * @nbranch: branches to child nodes
607  */
608 struct ubifs_nnode {
609 	struct ubifs_nnode *parent;
610 	struct ubifs_cnode *cnext;
611 	unsigned long flags;
612 	int iip;
613 	int level;
614 	int num;
615 	struct ubifs_nbranch nbranch[UBIFS_LPT_FANOUT];
616 };
617 
618 /**
619  * struct ubifs_lpt_heap - heap of categorized lprops.
620  * @arr: heap array
621  * @cnt: number in heap
622  * @max_cnt: maximum number allowed in heap
623  *
624  * There are %LPROPS_HEAP_CNT heaps.
625  */
626 struct ubifs_lpt_heap {
627 	struct ubifs_lprops **arr;
628 	int cnt;
629 	int max_cnt;
630 };
631 
632 /*
633  * Return codes for LPT scan callback function.
634  *
635  * LPT_SCAN_CONTINUE: continue scanning
636  * LPT_SCAN_ADD: add the LEB properties scanned to the tree in memory
637  * LPT_SCAN_STOP: stop scanning
638  */
639 enum {
640 	LPT_SCAN_CONTINUE = 0,
641 	LPT_SCAN_ADD = 1,
642 	LPT_SCAN_STOP = 2,
643 };
644 
645 struct ubifs_info;
646 
647 /* Callback used by the 'ubifs_lpt_scan_nolock()' function */
648 typedef int (*ubifs_lpt_scan_callback)(struct ubifs_info *c,
649 				       const struct ubifs_lprops *lprops,
650 				       int in_tree, void *data);
651 
652 /**
653  * struct ubifs_wbuf - UBIFS write-buffer.
654  * @c: UBIFS file-system description object
655  * @buf: write-buffer (of min. flash I/O unit size)
656  * @lnum: logical eraseblock number the write-buffer points to
657  * @offs: write-buffer offset in this logical eraseblock
658  * @avail: number of bytes available in the write-buffer
659  * @used:  number of used bytes in the write-buffer
660  * @size: write-buffer size (in [@c->min_io_size, @c->max_write_size] range)
661  * @jhead: journal head the mutex belongs to (note, needed only to shut lockdep
662  *         up by 'mutex_lock_nested()).
663  * @sync_callback: write-buffer synchronization callback
664  * @io_mutex: serializes write-buffer I/O
665  * @lock: serializes @buf, @lnum, @offs, @avail, @used, @next_ino and @inodes
666  *        fields
667  * @timer: write-buffer timer
668  * @no_timer: non-zero if this write-buffer does not have a timer
669  * @need_sync: non-zero if the timer expired and the wbuf needs sync'ing
670  * @next_ino: points to the next position of the following inode number
671  * @inodes: stores the inode numbers of the nodes which are in wbuf
672  *
673  * The write-buffer synchronization callback is called when the write-buffer is
674  * synchronized in order to notify how much space was wasted due to
675  * write-buffer padding and how much free space is left in the LEB.
676  *
677  * Note: the fields @buf, @lnum, @offs, @avail and @used can be read under
678  * spin-lock or mutex because they are written under both mutex and spin-lock.
679  * @buf is appended to under mutex but overwritten under both mutex and
680  * spin-lock. Thus the data between @buf and @buf + @used can be read under
681  * spinlock.
682  */
683 struct ubifs_wbuf {
684 	struct ubifs_info *c;
685 	void *buf;
686 	int lnum;
687 	int offs;
688 	int avail;
689 	int used;
690 	int size;
691 	int jhead;
692 	int (*sync_callback)(struct ubifs_info *c, int lnum, int free, int pad);
693 	struct mutex io_mutex;
694 	spinlock_t lock;
695 	struct hrtimer timer;
696 	unsigned int no_timer:1;
697 	unsigned int need_sync:1;
698 	int next_ino;
699 	ino_t *inodes;
700 };
701 
702 /**
703  * struct ubifs_bud - bud logical eraseblock.
704  * @lnum: logical eraseblock number
705  * @start: where the (uncommitted) bud data starts
706  * @jhead: journal head number this bud belongs to
707  * @list: link in the list buds belonging to the same journal head
708  * @rb: link in the tree of all buds
709  * @log_hash: the log hash from the commit start node up to this bud
710  */
711 struct ubifs_bud {
712 	int lnum;
713 	int start;
714 	int jhead;
715 	struct list_head list;
716 	struct rb_node rb;
717 	struct shash_desc *log_hash;
718 };
719 
720 /**
721  * struct ubifs_jhead - journal head.
722  * @wbuf: head's write-buffer
723  * @buds_list: list of bud LEBs belonging to this journal head
724  * @grouped: non-zero if UBIFS groups nodes when writing to this journal head
725  * @log_hash: the log hash from the commit start node up to this journal head
726  *
727  * Note, the @buds list is protected by the @c->buds_lock.
728  */
729 struct ubifs_jhead {
730 	struct ubifs_wbuf wbuf;
731 	struct list_head buds_list;
732 	unsigned int grouped:1;
733 	struct shash_desc *log_hash;
734 };
735 
736 /**
737  * struct ubifs_zbranch - key/coordinate/length branch stored in znodes.
738  * @key: key
739  * @znode: znode address in memory
740  * @lnum: LEB number of the target node (indexing node or data node)
741  * @offs: target node offset within @lnum
742  * @len: target node length
743  * @hash: the hash of the target node
744  */
745 struct ubifs_zbranch {
746 	union ubifs_key key;
747 	union {
748 		struct ubifs_znode *znode;
749 		void *leaf;
750 	};
751 	int lnum;
752 	int offs;
753 	int len;
754 	u8 hash[UBIFS_HASH_ARR_SZ];
755 };
756 
757 /**
758  * struct ubifs_znode - in-memory representation of an indexing node.
759  * @parent: parent znode or NULL if it is the root
760  * @cnext: next znode to commit
761  * @cparent: parent node for this commit
762  * @ciip: index in cparent's zbranch array
763  * @flags: znode flags (%DIRTY_ZNODE, %COW_ZNODE or %OBSOLETE_ZNODE)
764  * @time: last access time (seconds)
765  * @level: level of the entry in the TNC tree
766  * @child_cnt: count of child znodes
767  * @iip: index in parent's zbranch array
768  * @alt: lower bound of key range has altered i.e. child inserted at slot 0
769  * @lnum: LEB number of the corresponding indexing node
770  * @offs: offset of the corresponding indexing node
771  * @len: length  of the corresponding indexing node
772  * @zbranch: array of znode branches (@c->fanout elements)
773  *
774  * Note! The @lnum, @offs, and @len fields are not really needed - we have them
775  * only for internal consistency check. They could be removed to save some RAM.
776  */
777 struct ubifs_znode {
778 	struct ubifs_znode *parent;
779 	struct ubifs_znode *cnext;
780 	struct ubifs_znode *cparent;
781 	int ciip;
782 	unsigned long flags;
783 	time64_t time;
784 	int level;
785 	int child_cnt;
786 	int iip;
787 	int alt;
788 	int lnum;
789 	int offs;
790 	int len;
791 	struct ubifs_zbranch zbranch[];
792 };
793 
794 /**
795  * struct bu_info - bulk-read information.
796  * @key: first data node key
797  * @zbranch: zbranches of data nodes to bulk read
798  * @buf: buffer to read into
799  * @buf_len: buffer length
800  * @gc_seq: GC sequence number to detect races with GC
801  * @cnt: number of data nodes for bulk read
802  * @blk_cnt: number of data blocks including holes
803  * @oef: end of file reached
804  */
805 struct bu_info {
806 	union ubifs_key key;
807 	struct ubifs_zbranch zbranch[UBIFS_MAX_BULK_READ];
808 	void *buf;
809 	int buf_len;
810 	int gc_seq;
811 	int cnt;
812 	int blk_cnt;
813 	int eof;
814 };
815 
816 /**
817  * struct ubifs_node_range - node length range description data structure.
818  * @len: fixed node length
819  * @min_len: minimum possible node length
820  * @max_len: maximum possible node length
821  *
822  * If @max_len is %0, the node has fixed length @len.
823  */
824 struct ubifs_node_range {
825 	union {
826 		int len;
827 		int min_len;
828 	};
829 	int max_len;
830 };
831 
832 /**
833  * struct ubifs_compressor - UBIFS compressor description structure.
834  * @compr_type: compressor type (%UBIFS_COMPR_LZO, etc)
835  * @cc: cryptoapi compressor handle
836  * @comp_mutex: mutex used during compression
837  * @decomp_mutex: mutex used during decompression
838  * @name: compressor name
839  * @capi_name: cryptoapi compressor name
840  */
841 struct ubifs_compressor {
842 	int compr_type;
843 	struct crypto_comp *cc;
844 	struct mutex *comp_mutex;
845 	struct mutex *decomp_mutex;
846 	const char *name;
847 	const char *capi_name;
848 };
849 
850 /**
851  * struct ubifs_budget_req - budget requirements of an operation.
852  *
853  * @fast: non-zero if the budgeting should try to acquire budget quickly and
854  *        should not try to call write-back
855  * @recalculate: non-zero if @idx_growth, @data_growth, and @dd_growth fields
856  *               have to be re-calculated
857  * @new_page: non-zero if the operation adds a new page
858  * @dirtied_page: non-zero if the operation makes a page dirty
859  * @new_dent: non-zero if the operation adds a new directory entry
860  * @mod_dent: non-zero if the operation removes or modifies an existing
861  *            directory entry
862  * @new_ino: non-zero if the operation adds a new inode
863  * @new_ino_d: how much data newly created inode contains
864  * @dirtied_ino: how many inodes the operation makes dirty
865  * @dirtied_ino_d: how much data dirtied inode contains
866  * @idx_growth: how much the index will supposedly grow
867  * @data_growth: how much new data the operation will supposedly add
868  * @dd_growth: how much data that makes other data dirty the operation will
869  *             supposedly add
870  *
871  * @idx_growth, @data_growth and @dd_growth are not used in budget request. The
872  * budgeting subsystem caches index and data growth values there to avoid
873  * re-calculating them when the budget is released. However, if @idx_growth is
874  * %-1, it is calculated by the release function using other fields.
875  *
876  * An inode may contain 4KiB of data at max., thus the widths of @new_ino_d
877  * is 13 bits, and @dirtied_ino_d - 15, because up to 4 inodes may be made
878  * dirty by the re-name operation.
879  *
880  * Note, UBIFS aligns node lengths to 8-bytes boundary, so the requester has to
881  * make sure the amount of inode data which contribute to @new_ino_d and
882  * @dirtied_ino_d fields are aligned.
883  */
884 struct ubifs_budget_req {
885 	unsigned int fast:1;
886 	unsigned int recalculate:1;
887 #ifndef UBIFS_DEBUG
888 	unsigned int new_page:1;
889 	unsigned int dirtied_page:1;
890 	unsigned int new_dent:1;
891 	unsigned int mod_dent:1;
892 	unsigned int new_ino:1;
893 	unsigned int new_ino_d:13;
894 	unsigned int dirtied_ino:4;
895 	unsigned int dirtied_ino_d:15;
896 #else
897 	/* Not bit-fields to check for overflows */
898 	unsigned int new_page;
899 	unsigned int dirtied_page;
900 	unsigned int new_dent;
901 	unsigned int mod_dent;
902 	unsigned int new_ino;
903 	unsigned int new_ino_d;
904 	unsigned int dirtied_ino;
905 	unsigned int dirtied_ino_d;
906 #endif
907 	int idx_growth;
908 	int data_growth;
909 	int dd_growth;
910 };
911 
912 /**
913  * struct ubifs_orphan - stores the inode number of an orphan.
914  * @rb: rb-tree node of rb-tree of orphans sorted by inode number
915  * @list: list head of list of orphans in order added
916  * @new_list: list head of list of orphans added since the last commit
917  * @child_list: list of xattr children if this orphan hosts xattrs, list head
918  * if this orphan is a xattr, not used otherwise.
919  * @cnext: next orphan to commit
920  * @dnext: next orphan to delete
921  * @inum: inode number
922  * @new: %1 => added since the last commit, otherwise %0
923  * @cmt: %1 => commit pending, otherwise %0
924  * @del: %1 => delete pending, otherwise %0
925  */
926 struct ubifs_orphan {
927 	struct rb_node rb;
928 	struct list_head list;
929 	struct list_head new_list;
930 	struct list_head child_list;
931 	struct ubifs_orphan *cnext;
932 	struct ubifs_orphan *dnext;
933 	ino_t inum;
934 	unsigned new:1;
935 	unsigned cmt:1;
936 	unsigned del:1;
937 };
938 
939 /**
940  * struct ubifs_mount_opts - UBIFS-specific mount options information.
941  * @unmount_mode: selected unmount mode (%0 default, %1 normal, %2 fast)
942  * @bulk_read: enable/disable bulk-reads (%0 default, %1 disable, %2 enable)
943  * @chk_data_crc: enable/disable CRC data checking when reading data nodes
944  *                (%0 default, %1 disable, %2 enable)
945  * @override_compr: override default compressor (%0 - do not override and use
946  *                  superblock compressor, %1 - override and use compressor
947  *                  specified in @compr_type)
948  * @compr_type: compressor type to override the superblock compressor with
949  *              (%UBIFS_COMPR_NONE, etc)
950  */
951 struct ubifs_mount_opts {
952 	unsigned int unmount_mode:2;
953 	unsigned int bulk_read:2;
954 	unsigned int chk_data_crc:2;
955 	unsigned int override_compr:1;
956 	unsigned int compr_type:2;
957 };
958 
959 /**
960  * struct ubifs_budg_info - UBIFS budgeting information.
961  * @idx_growth: amount of bytes budgeted for index growth
962  * @data_growth: amount of bytes budgeted for cached data
963  * @dd_growth: amount of bytes budgeted for cached data that will make
964  *             other data dirty
965  * @uncommitted_idx: amount of bytes were budgeted for growth of the index, but
966  *                   which still have to be taken into account because the index
967  *                   has not been committed so far
968  * @old_idx_sz: size of index on flash
969  * @min_idx_lebs: minimum number of LEBs required for the index
970  * @nospace: non-zero if the file-system does not have flash space (used as
971  *           optimization)
972  * @nospace_rp: the same as @nospace, but additionally means that even reserved
973  *              pool is full
974  * @page_budget: budget for a page (constant, never changed after mount)
975  * @inode_budget: budget for an inode (constant, never changed after mount)
976  * @dent_budget: budget for a directory entry (constant, never changed after
977  *               mount)
978  */
979 struct ubifs_budg_info {
980 	long long idx_growth;
981 	long long data_growth;
982 	long long dd_growth;
983 	long long uncommitted_idx;
984 	unsigned long long old_idx_sz;
985 	int min_idx_lebs;
986 	unsigned int nospace:1;
987 	unsigned int nospace_rp:1;
988 	int page_budget;
989 	int inode_budget;
990 	int dent_budget;
991 };
992 
993 struct ubifs_debug_info;
994 
995 /**
996  * struct ubifs_info - UBIFS file-system description data structure
997  * (per-superblock).
998  * @vfs_sb: VFS @struct super_block object
999  * @sup_node: The super block node as read from the device
1000  *
1001  * @highest_inum: highest used inode number
1002  * @max_sqnum: current global sequence number
1003  * @cmt_no: commit number of the last successfully completed commit, protected
1004  *          by @commit_sem
1005  * @cnt_lock: protects @highest_inum and @max_sqnum counters
1006  * @fmt_version: UBIFS on-flash format version
1007  * @ro_compat_version: R/O compatibility version
1008  * @uuid: UUID from super block
1009  *
1010  * @lhead_lnum: log head logical eraseblock number
1011  * @lhead_offs: log head offset
1012  * @ltail_lnum: log tail logical eraseblock number (offset is always 0)
1013  * @log_mutex: protects the log, @lhead_lnum, @lhead_offs, @ltail_lnum, and
1014  *             @bud_bytes
1015  * @min_log_bytes: minimum required number of bytes in the log
1016  * @cmt_bud_bytes: used during commit to temporarily amount of bytes in
1017  *                 committed buds
1018  *
1019  * @buds: tree of all buds indexed by bud LEB number
1020  * @bud_bytes: how many bytes of flash is used by buds
1021  * @buds_lock: protects the @buds tree, @bud_bytes, and per-journal head bud
1022  *             lists
1023  * @jhead_cnt: count of journal heads
1024  * @jheads: journal heads (head zero is base head)
1025  * @max_bud_bytes: maximum number of bytes allowed in buds
1026  * @bg_bud_bytes: number of bud bytes when background commit is initiated
1027  * @old_buds: buds to be released after commit ends
1028  * @max_bud_cnt: maximum number of buds
1029  *
1030  * @commit_sem: synchronizes committer with other processes
1031  * @cmt_state: commit state
1032  * @cs_lock: commit state lock
1033  * @cmt_wq: wait queue to sleep on if the log is full and a commit is running
1034  *
1035  * @big_lpt: flag that LPT is too big to write whole during commit
1036  * @space_fixup: flag indicating that free space in LEBs needs to be cleaned up
1037  * @double_hash: flag indicating that we can do lookups by hash
1038  * @encrypted: flag indicating that this file system contains encrypted files
1039  * @no_chk_data_crc: do not check CRCs when reading data nodes (except during
1040  *                   recovery)
1041  * @bulk_read: enable bulk-reads
1042  * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc)
1043  * @rw_incompat: the media is not R/W compatible
1044  * @assert_action: action to take when a ubifs_assert() fails
1045  * @authenticated: flag indigating the FS is mounted in authenticated mode
1046  *
1047  * @tnc_mutex: protects the Tree Node Cache (TNC), @zroot, @cnext, @enext, and
1048  *             @calc_idx_sz
1049  * @zroot: zbranch which points to the root index node and znode
1050  * @cnext: next znode to commit
1051  * @enext: next znode to commit to empty space
1052  * @gap_lebs: array of LEBs used by the in-gaps commit method
1053  * @cbuf: commit buffer
1054  * @ileb_buf: buffer for commit in-the-gaps method
1055  * @ileb_len: length of data in ileb_buf
1056  * @ihead_lnum: LEB number of index head
1057  * @ihead_offs: offset of index head
1058  * @ilebs: pre-allocated index LEBs
1059  * @ileb_cnt: number of pre-allocated index LEBs
1060  * @ileb_nxt: next pre-allocated index LEBs
1061  * @old_idx: tree of index nodes obsoleted since the last commit start
1062  * @bottom_up_buf: a buffer which is used by 'dirty_cow_bottom_up()' in tnc.c
1063  *
1064  * @mst_node: master node
1065  * @mst_offs: offset of valid master node
1066  *
1067  * @max_bu_buf_len: maximum bulk-read buffer length
1068  * @bu_mutex: protects the pre-allocated bulk-read buffer and @c->bu
1069  * @bu: pre-allocated bulk-read information
1070  *
1071  * @write_reserve_mutex: protects @write_reserve_buf
1072  * @write_reserve_buf: on the write path we allocate memory, which might
1073  *                     sometimes be unavailable, in which case we use this
1074  *                     write reserve buffer
1075  *
1076  * @log_lebs: number of logical eraseblocks in the log
1077  * @log_bytes: log size in bytes
1078  * @log_last: last LEB of the log
1079  * @lpt_lebs: number of LEBs used for lprops table
1080  * @lpt_first: first LEB of the lprops table area
1081  * @lpt_last: last LEB of the lprops table area
1082  * @orph_lebs: number of LEBs used for the orphan area
1083  * @orph_first: first LEB of the orphan area
1084  * @orph_last: last LEB of the orphan area
1085  * @main_lebs: count of LEBs in the main area
1086  * @main_first: first LEB of the main area
1087  * @main_bytes: main area size in bytes
1088  *
1089  * @key_hash_type: type of the key hash
1090  * @key_hash: direntry key hash function
1091  * @key_fmt: key format
1092  * @key_len: key length
1093  * @hash_len: The length of the index node hashes
1094  * @fanout: fanout of the index tree (number of links per indexing node)
1095  *
1096  * @min_io_size: minimal input/output unit size
1097  * @min_io_shift: number of bits in @min_io_size minus one
1098  * @max_write_size: maximum amount of bytes the underlying flash can write at a
1099  *                  time (MTD write buffer size)
1100  * @max_write_shift: number of bits in @max_write_size minus one
1101  * @leb_size: logical eraseblock size in bytes
1102  * @leb_start: starting offset of logical eraseblocks within physical
1103  *             eraseblocks
1104  * @half_leb_size: half LEB size
1105  * @idx_leb_size: how many bytes of an LEB are effectively available when it is
1106  *                used to store indexing nodes (@leb_size - @max_idx_node_sz)
1107  * @leb_cnt: count of logical eraseblocks
1108  * @max_leb_cnt: maximum count of logical eraseblocks
1109  * @ro_media: the underlying UBI volume is read-only
1110  * @ro_mount: the file-system was mounted as read-only
1111  * @ro_error: UBIFS switched to R/O mode because an error happened
1112  *
1113  * @dirty_pg_cnt: number of dirty pages (not used)
1114  * @dirty_zn_cnt: number of dirty znodes
1115  * @clean_zn_cnt: number of clean znodes
1116  *
1117  * @space_lock: protects @bi and @lst
1118  * @lst: lprops statistics
1119  * @bi: budgeting information
1120  * @calc_idx_sz: temporary variable which is used to calculate new index size
1121  *               (contains accurate new index size at end of TNC commit start)
1122  *
1123  * @ref_node_alsz: size of the LEB reference node aligned to the min. flash
1124  *                 I/O unit
1125  * @mst_node_alsz: master node aligned size
1126  * @min_idx_node_sz: minimum indexing node aligned on 8-bytes boundary
1127  * @max_idx_node_sz: maximum indexing node aligned on 8-bytes boundary
1128  * @max_inode_sz: maximum possible inode size in bytes
1129  * @max_znode_sz: size of znode in bytes
1130  *
1131  * @leb_overhead: how many bytes are wasted in an LEB when it is filled with
1132  *                data nodes of maximum size - used in free space reporting
1133  * @dead_wm: LEB dead space watermark
1134  * @dark_wm: LEB dark space watermark
1135  * @block_cnt: count of 4KiB blocks on the FS
1136  *
1137  * @ranges: UBIFS node length ranges
1138  * @ubi: UBI volume descriptor
1139  * @di: UBI device information
1140  * @vi: UBI volume information
1141  *
1142  * @orph_tree: rb-tree of orphan inode numbers
1143  * @orph_list: list of orphan inode numbers in order added
1144  * @orph_new: list of orphan inode numbers added since last commit
1145  * @orph_cnext: next orphan to commit
1146  * @orph_dnext: next orphan to delete
1147  * @orphan_lock: lock for orph_tree and orph_new
1148  * @orph_buf: buffer for orphan nodes
1149  * @new_orphans: number of orphans since last commit
1150  * @cmt_orphans: number of orphans being committed
1151  * @tot_orphans: number of orphans in the rb_tree
1152  * @max_orphans: maximum number of orphans allowed
1153  * @ohead_lnum: orphan head LEB number
1154  * @ohead_offs: orphan head offset
1155  * @no_orphs: non-zero if there are no orphans
1156  *
1157  * @bgt: UBIFS background thread
1158  * @bgt_name: background thread name
1159  * @need_bgt: if background thread should run
1160  * @need_wbuf_sync: if write-buffers have to be synchronized
1161  *
1162  * @gc_lnum: LEB number used for garbage collection
1163  * @sbuf: a buffer of LEB size used by GC and replay for scanning
1164  * @idx_gc: list of index LEBs that have been garbage collected
1165  * @idx_gc_cnt: number of elements on the idx_gc list
1166  * @gc_seq: incremented for every non-index LEB garbage collected
1167  * @gced_lnum: last non-index LEB that was garbage collected
1168  *
1169  * @infos_list: links all 'ubifs_info' objects
1170  * @umount_mutex: serializes shrinker and un-mount
1171  * @shrinker_run_no: shrinker run number
1172  *
1173  * @space_bits: number of bits needed to record free or dirty space
1174  * @lpt_lnum_bits: number of bits needed to record a LEB number in the LPT
1175  * @lpt_offs_bits: number of bits needed to record an offset in the LPT
1176  * @lpt_spc_bits: number of bits needed to space in the LPT
1177  * @pcnt_bits: number of bits needed to record pnode or nnode number
1178  * @lnum_bits: number of bits needed to record LEB number
1179  * @nnode_sz: size of on-flash nnode
1180  * @pnode_sz: size of on-flash pnode
1181  * @ltab_sz: size of on-flash LPT lprops table
1182  * @lsave_sz: size of on-flash LPT save table
1183  * @pnode_cnt: number of pnodes
1184  * @nnode_cnt: number of nnodes
1185  * @lpt_hght: height of the LPT
1186  * @pnodes_have: number of pnodes in memory
1187  *
1188  * @lp_mutex: protects lprops table and all the other lprops-related fields
1189  * @lpt_lnum: LEB number of the root nnode of the LPT
1190  * @lpt_offs: offset of the root nnode of the LPT
1191  * @nhead_lnum: LEB number of LPT head
1192  * @nhead_offs: offset of LPT head
1193  * @lpt_drty_flgs: dirty flags for LPT special nodes e.g. ltab
1194  * @dirty_nn_cnt: number of dirty nnodes
1195  * @dirty_pn_cnt: number of dirty pnodes
1196  * @check_lpt_free: flag that indicates LPT GC may be needed
1197  * @lpt_sz: LPT size
1198  * @lpt_nod_buf: buffer for an on-flash nnode or pnode
1199  * @lpt_buf: buffer of LEB size used by LPT
1200  * @nroot: address in memory of the root nnode of the LPT
1201  * @lpt_cnext: next LPT node to commit
1202  * @lpt_heap: array of heaps of categorized lprops
1203  * @dirty_idx: a (reverse sorted) copy of the LPROPS_DIRTY_IDX heap as at
1204  *             previous commit start
1205  * @uncat_list: list of un-categorized LEBs
1206  * @empty_list: list of empty LEBs
1207  * @freeable_list: list of freeable non-index LEBs (free + dirty == @leb_size)
1208  * @frdi_idx_list: list of freeable index LEBs (free + dirty == @leb_size)
1209  * @freeable_cnt: number of freeable LEBs in @freeable_list
1210  * @in_a_category_cnt: count of lprops which are in a certain category, which
1211  *                     basically meants that they were loaded from the flash
1212  *
1213  * @ltab_lnum: LEB number of LPT's own lprops table
1214  * @ltab_offs: offset of LPT's own lprops table
1215  * @ltab: LPT's own lprops table
1216  * @ltab_cmt: LPT's own lprops table (commit copy)
1217  * @lsave_cnt: number of LEB numbers in LPT's save table
1218  * @lsave_lnum: LEB number of LPT's save table
1219  * @lsave_offs: offset of LPT's save table
1220  * @lsave: LPT's save table
1221  * @lscan_lnum: LEB number of last LPT scan
1222  *
1223  * @rp_size: size of the reserved pool in bytes
1224  * @report_rp_size: size of the reserved pool reported to user-space
1225  * @rp_uid: reserved pool user ID
1226  * @rp_gid: reserved pool group ID
1227  *
1228  * @hash_tfm: the hash transformation used for hashing nodes
1229  * @hmac_tfm: the HMAC transformation for this filesystem
1230  * @hmac_desc_len: length of the HMAC used for authentication
1231  * @auth_key_name: the authentication key name
1232  * @auth_hash_name: the name of the hash algorithm used for authentication
1233  * @auth_hash_algo: the authentication hash used for this fs
1234  * @log_hash: the log hash from the commit start node up to the latest reference
1235  *            node.
1236  *
1237  * @empty: %1 if the UBI device is empty
1238  * @need_recovery: %1 if the file-system needs recovery
1239  * @replaying: %1 during journal replay
1240  * @mounting: %1 while mounting
1241  * @probing: %1 while attempting to mount if SB_SILENT mount flag is set
1242  * @remounting_rw: %1 while re-mounting from R/O mode to R/W mode
1243  * @replay_list: temporary list used during journal replay
1244  * @replay_buds: list of buds to replay
1245  * @cs_sqnum: sequence number of first node in the log (commit start node)
1246  * @unclean_leb_list: LEBs to recover when re-mounting R/O mounted FS to R/W
1247  *                    mode
1248  * @rcvrd_mst_node: recovered master node to write when re-mounting R/O mounted
1249  *                  FS to R/W mode
1250  * @size_tree: inode size information for recovery
1251  * @mount_opts: UBIFS-specific mount options
1252  *
1253  * @dbg: debugging-related information
1254  */
1255 struct ubifs_info {
1256 	struct super_block *vfs_sb;
1257 	struct ubifs_sb_node *sup_node;
1258 
1259 	ino_t highest_inum;
1260 	unsigned long long max_sqnum;
1261 	unsigned long long cmt_no;
1262 	spinlock_t cnt_lock;
1263 	int fmt_version;
1264 	int ro_compat_version;
1265 	unsigned char uuid[16];
1266 
1267 	int lhead_lnum;
1268 	int lhead_offs;
1269 	int ltail_lnum;
1270 	struct mutex log_mutex;
1271 	int min_log_bytes;
1272 	long long cmt_bud_bytes;
1273 
1274 	struct rb_root buds;
1275 	long long bud_bytes;
1276 	spinlock_t buds_lock;
1277 	int jhead_cnt;
1278 	struct ubifs_jhead *jheads;
1279 	long long max_bud_bytes;
1280 	long long bg_bud_bytes;
1281 	struct list_head old_buds;
1282 	int max_bud_cnt;
1283 
1284 	struct rw_semaphore commit_sem;
1285 	int cmt_state;
1286 	spinlock_t cs_lock;
1287 	wait_queue_head_t cmt_wq;
1288 
1289 	unsigned int big_lpt:1;
1290 	unsigned int space_fixup:1;
1291 	unsigned int double_hash:1;
1292 	unsigned int encrypted:1;
1293 	unsigned int no_chk_data_crc:1;
1294 	unsigned int bulk_read:1;
1295 	unsigned int default_compr:2;
1296 	unsigned int rw_incompat:1;
1297 	unsigned int assert_action:2;
1298 	unsigned int authenticated:1;
1299 	unsigned int superblock_need_write:1;
1300 
1301 	struct mutex tnc_mutex;
1302 	struct ubifs_zbranch zroot;
1303 	struct ubifs_znode *cnext;
1304 	struct ubifs_znode *enext;
1305 	int *gap_lebs;
1306 	void *cbuf;
1307 	void *ileb_buf;
1308 	int ileb_len;
1309 	int ihead_lnum;
1310 	int ihead_offs;
1311 	int *ilebs;
1312 	int ileb_cnt;
1313 	int ileb_nxt;
1314 	struct rb_root old_idx;
1315 	int *bottom_up_buf;
1316 
1317 	struct ubifs_mst_node *mst_node;
1318 	int mst_offs;
1319 
1320 	int max_bu_buf_len;
1321 	struct mutex bu_mutex;
1322 	struct bu_info bu;
1323 
1324 	struct mutex write_reserve_mutex;
1325 	void *write_reserve_buf;
1326 
1327 	int log_lebs;
1328 	long long log_bytes;
1329 	int log_last;
1330 	int lpt_lebs;
1331 	int lpt_first;
1332 	int lpt_last;
1333 	int orph_lebs;
1334 	int orph_first;
1335 	int orph_last;
1336 	int main_lebs;
1337 	int main_first;
1338 	long long main_bytes;
1339 
1340 	uint8_t key_hash_type;
1341 	uint32_t (*key_hash)(const char *str, int len);
1342 	int key_fmt;
1343 	int key_len;
1344 	int hash_len;
1345 	int fanout;
1346 
1347 	int min_io_size;
1348 	int min_io_shift;
1349 	int max_write_size;
1350 	int max_write_shift;
1351 	int leb_size;
1352 	int leb_start;
1353 	int half_leb_size;
1354 	int idx_leb_size;
1355 	int leb_cnt;
1356 	int max_leb_cnt;
1357 	unsigned int ro_media:1;
1358 	unsigned int ro_mount:1;
1359 	unsigned int ro_error:1;
1360 
1361 	atomic_long_t dirty_pg_cnt;
1362 	atomic_long_t dirty_zn_cnt;
1363 	atomic_long_t clean_zn_cnt;
1364 
1365 	spinlock_t space_lock;
1366 	struct ubifs_lp_stats lst;
1367 	struct ubifs_budg_info bi;
1368 	unsigned long long calc_idx_sz;
1369 
1370 	int ref_node_alsz;
1371 	int mst_node_alsz;
1372 	int min_idx_node_sz;
1373 	int max_idx_node_sz;
1374 	long long max_inode_sz;
1375 	int max_znode_sz;
1376 
1377 	int leb_overhead;
1378 	int dead_wm;
1379 	int dark_wm;
1380 	int block_cnt;
1381 
1382 	struct ubifs_node_range ranges[UBIFS_NODE_TYPES_CNT];
1383 	struct ubi_volume_desc *ubi;
1384 	struct ubi_device_info di;
1385 	struct ubi_volume_info vi;
1386 
1387 	struct rb_root orph_tree;
1388 	struct list_head orph_list;
1389 	struct list_head orph_new;
1390 	struct ubifs_orphan *orph_cnext;
1391 	struct ubifs_orphan *orph_dnext;
1392 	spinlock_t orphan_lock;
1393 	void *orph_buf;
1394 	int new_orphans;
1395 	int cmt_orphans;
1396 	int tot_orphans;
1397 	int max_orphans;
1398 	int ohead_lnum;
1399 	int ohead_offs;
1400 	int no_orphs;
1401 
1402 	struct task_struct *bgt;
1403 	char bgt_name[sizeof(BGT_NAME_PATTERN) + 9];
1404 	int need_bgt;
1405 	int need_wbuf_sync;
1406 
1407 	int gc_lnum;
1408 	void *sbuf;
1409 	struct list_head idx_gc;
1410 	int idx_gc_cnt;
1411 	int gc_seq;
1412 	int gced_lnum;
1413 
1414 	struct list_head infos_list;
1415 	struct mutex umount_mutex;
1416 	unsigned int shrinker_run_no;
1417 
1418 	int space_bits;
1419 	int lpt_lnum_bits;
1420 	int lpt_offs_bits;
1421 	int lpt_spc_bits;
1422 	int pcnt_bits;
1423 	int lnum_bits;
1424 	int nnode_sz;
1425 	int pnode_sz;
1426 	int ltab_sz;
1427 	int lsave_sz;
1428 	int pnode_cnt;
1429 	int nnode_cnt;
1430 	int lpt_hght;
1431 	int pnodes_have;
1432 
1433 	struct mutex lp_mutex;
1434 	int lpt_lnum;
1435 	int lpt_offs;
1436 	int nhead_lnum;
1437 	int nhead_offs;
1438 	int lpt_drty_flgs;
1439 	int dirty_nn_cnt;
1440 	int dirty_pn_cnt;
1441 	int check_lpt_free;
1442 	long long lpt_sz;
1443 	void *lpt_nod_buf;
1444 	void *lpt_buf;
1445 	struct ubifs_nnode *nroot;
1446 	struct ubifs_cnode *lpt_cnext;
1447 	struct ubifs_lpt_heap lpt_heap[LPROPS_HEAP_CNT];
1448 	struct ubifs_lpt_heap dirty_idx;
1449 	struct list_head uncat_list;
1450 	struct list_head empty_list;
1451 	struct list_head freeable_list;
1452 	struct list_head frdi_idx_list;
1453 	int freeable_cnt;
1454 	int in_a_category_cnt;
1455 
1456 	int ltab_lnum;
1457 	int ltab_offs;
1458 	struct ubifs_lpt_lprops *ltab;
1459 	struct ubifs_lpt_lprops *ltab_cmt;
1460 	int lsave_cnt;
1461 	int lsave_lnum;
1462 	int lsave_offs;
1463 	int *lsave;
1464 	int lscan_lnum;
1465 
1466 	long long rp_size;
1467 	long long report_rp_size;
1468 	kuid_t rp_uid;
1469 	kgid_t rp_gid;
1470 
1471 	struct crypto_shash *hash_tfm;
1472 	struct crypto_shash *hmac_tfm;
1473 	int hmac_desc_len;
1474 	char *auth_key_name;
1475 	char *auth_hash_name;
1476 	enum hash_algo auth_hash_algo;
1477 
1478 	struct shash_desc *log_hash;
1479 
1480 	/* The below fields are used only during mounting and re-mounting */
1481 	unsigned int empty:1;
1482 	unsigned int need_recovery:1;
1483 	unsigned int replaying:1;
1484 	unsigned int mounting:1;
1485 	unsigned int remounting_rw:1;
1486 	unsigned int probing:1;
1487 	struct list_head replay_list;
1488 	struct list_head replay_buds;
1489 	unsigned long long cs_sqnum;
1490 	struct list_head unclean_leb_list;
1491 	struct ubifs_mst_node *rcvrd_mst_node;
1492 	struct rb_root size_tree;
1493 	struct ubifs_mount_opts mount_opts;
1494 
1495 	struct ubifs_debug_info *dbg;
1496 };
1497 
1498 extern struct list_head ubifs_infos;
1499 extern spinlock_t ubifs_infos_lock;
1500 extern atomic_long_t ubifs_clean_zn_cnt;
1501 extern const struct super_operations ubifs_super_operations;
1502 extern const struct address_space_operations ubifs_file_address_operations;
1503 extern const struct file_operations ubifs_file_operations;
1504 extern const struct inode_operations ubifs_file_inode_operations;
1505 extern const struct file_operations ubifs_dir_operations;
1506 extern const struct inode_operations ubifs_dir_inode_operations;
1507 extern const struct inode_operations ubifs_symlink_inode_operations;
1508 extern struct ubifs_compressor *ubifs_compressors[UBIFS_COMPR_TYPES_CNT];
1509 extern int ubifs_default_version;
1510 
1511 /* auth.c */
1512 static inline int ubifs_authenticated(const struct ubifs_info *c)
1513 {
1514 	return (IS_ENABLED(CONFIG_UBIFS_FS_AUTHENTICATION)) && c->authenticated;
1515 }
1516 
1517 struct shash_desc *__ubifs_hash_get_desc(const struct ubifs_info *c);
1518 static inline struct shash_desc *ubifs_hash_get_desc(const struct ubifs_info *c)
1519 {
1520 	return ubifs_authenticated(c) ? __ubifs_hash_get_desc(c) : NULL;
1521 }
1522 
1523 static inline int ubifs_shash_init(const struct ubifs_info *c,
1524 				   struct shash_desc *desc)
1525 {
1526 	if (ubifs_authenticated(c))
1527 		return crypto_shash_init(desc);
1528 	else
1529 		return 0;
1530 }
1531 
1532 static inline int ubifs_shash_update(const struct ubifs_info *c,
1533 				      struct shash_desc *desc, const void *buf,
1534 				      unsigned int len)
1535 {
1536 	int err = 0;
1537 
1538 	if (ubifs_authenticated(c)) {
1539 		err = crypto_shash_update(desc, buf, len);
1540 		if (err < 0)
1541 			return err;
1542 	}
1543 
1544 	return 0;
1545 }
1546 
1547 static inline int ubifs_shash_final(const struct ubifs_info *c,
1548 				    struct shash_desc *desc, u8 *out)
1549 {
1550 	return ubifs_authenticated(c) ? crypto_shash_final(desc, out) : 0;
1551 }
1552 
1553 int __ubifs_node_calc_hash(const struct ubifs_info *c, const void *buf,
1554 			  u8 *hash);
1555 static inline int ubifs_node_calc_hash(const struct ubifs_info *c,
1556 					const void *buf, u8 *hash)
1557 {
1558 	if (ubifs_authenticated(c))
1559 		return __ubifs_node_calc_hash(c, buf, hash);
1560 	else
1561 		return 0;
1562 }
1563 
1564 int ubifs_prepare_auth_node(struct ubifs_info *c, void *node,
1565 			     struct shash_desc *inhash);
1566 
1567 /**
1568  * ubifs_check_hash - compare two hashes
1569  * @c: UBIFS file-system description object
1570  * @expected: first hash
1571  * @got: second hash
1572  *
1573  * Compare two hashes @expected and @got. Returns 0 when they are equal, a
1574  * negative error code otherwise.
1575  */
1576 static inline int ubifs_check_hash(const struct ubifs_info *c,
1577 				   const u8 *expected, const u8 *got)
1578 {
1579 	return crypto_memneq(expected, got, c->hash_len);
1580 }
1581 
1582 /**
1583  * ubifs_check_hmac - compare two HMACs
1584  * @c: UBIFS file-system description object
1585  * @expected: first HMAC
1586  * @got: second HMAC
1587  *
1588  * Compare two hashes @expected and @got. Returns 0 when they are equal, a
1589  * negative error code otherwise.
1590  */
1591 static inline int ubifs_check_hmac(const struct ubifs_info *c,
1592 				   const u8 *expected, const u8 *got)
1593 {
1594 	return crypto_memneq(expected, got, c->hmac_desc_len);
1595 }
1596 
1597 void ubifs_bad_hash(const struct ubifs_info *c, const void *node,
1598 		    const u8 *hash, int lnum, int offs);
1599 
1600 int __ubifs_node_check_hash(const struct ubifs_info *c, const void *buf,
1601 			  const u8 *expected);
1602 static inline int ubifs_node_check_hash(const struct ubifs_info *c,
1603 					const void *buf, const u8 *expected)
1604 {
1605 	if (ubifs_authenticated(c))
1606 		return __ubifs_node_check_hash(c, buf, expected);
1607 	else
1608 		return 0;
1609 }
1610 
1611 int ubifs_init_authentication(struct ubifs_info *c);
1612 void __ubifs_exit_authentication(struct ubifs_info *c);
1613 static inline void ubifs_exit_authentication(struct ubifs_info *c)
1614 {
1615 	if (ubifs_authenticated(c))
1616 		__ubifs_exit_authentication(c);
1617 }
1618 
1619 /**
1620  * ubifs_branch_hash - returns a pointer to the hash of a branch
1621  * @c: UBIFS file-system description object
1622  * @br: branch to get the hash from
1623  *
1624  * This returns a pointer to the hash of a branch. Since the key already is a
1625  * dynamically sized object we cannot use a struct member here.
1626  */
1627 static inline u8 *ubifs_branch_hash(struct ubifs_info *c,
1628 				    struct ubifs_branch *br)
1629 {
1630 	return (void *)br + sizeof(*br) + c->key_len;
1631 }
1632 
1633 /**
1634  * ubifs_copy_hash - copy a hash
1635  * @c: UBIFS file-system description object
1636  * @from: source hash
1637  * @to: destination hash
1638  *
1639  * With authentication this copies a hash, otherwise does nothing.
1640  */
1641 static inline void ubifs_copy_hash(const struct ubifs_info *c, const u8 *from,
1642 				   u8 *to)
1643 {
1644 	if (ubifs_authenticated(c))
1645 		memcpy(to, from, c->hash_len);
1646 }
1647 
1648 int __ubifs_node_insert_hmac(const struct ubifs_info *c, void *buf,
1649 			      int len, int ofs_hmac);
1650 static inline int ubifs_node_insert_hmac(const struct ubifs_info *c, void *buf,
1651 					  int len, int ofs_hmac)
1652 {
1653 	if (ubifs_authenticated(c))
1654 		return __ubifs_node_insert_hmac(c, buf, len, ofs_hmac);
1655 	else
1656 		return 0;
1657 }
1658 
1659 int __ubifs_node_verify_hmac(const struct ubifs_info *c, const void *buf,
1660 			     int len, int ofs_hmac);
1661 static inline int ubifs_node_verify_hmac(const struct ubifs_info *c,
1662 					 const void *buf, int len, int ofs_hmac)
1663 {
1664 	if (ubifs_authenticated(c))
1665 		return __ubifs_node_verify_hmac(c, buf, len, ofs_hmac);
1666 	else
1667 		return 0;
1668 }
1669 
1670 /**
1671  * ubifs_auth_node_sz - returns the size of an authentication node
1672  * @c: UBIFS file-system description object
1673  *
1674  * This function returns the size of an authentication node which can
1675  * be 0 for unauthenticated filesystems or the real size of an auth node
1676  * authentication is enabled.
1677  */
1678 static inline int ubifs_auth_node_sz(const struct ubifs_info *c)
1679 {
1680 	if (ubifs_authenticated(c))
1681 		return sizeof(struct ubifs_auth_node) + c->hmac_desc_len;
1682 	else
1683 		return 0;
1684 }
1685 int ubifs_sb_verify_signature(struct ubifs_info *c,
1686 			      const struct ubifs_sb_node *sup);
1687 bool ubifs_hmac_zero(struct ubifs_info *c, const u8 *hmac);
1688 
1689 int ubifs_hmac_wkm(struct ubifs_info *c, u8 *hmac);
1690 
1691 int __ubifs_shash_copy_state(const struct ubifs_info *c, struct shash_desc *src,
1692 			     struct shash_desc *target);
1693 static inline int ubifs_shash_copy_state(const struct ubifs_info *c,
1694 					   struct shash_desc *src,
1695 					   struct shash_desc *target)
1696 {
1697 	if (ubifs_authenticated(c))
1698 		return __ubifs_shash_copy_state(c, src, target);
1699 	else
1700 		return 0;
1701 }
1702 
1703 /* io.c */
1704 void ubifs_ro_mode(struct ubifs_info *c, int err);
1705 int ubifs_leb_read(const struct ubifs_info *c, int lnum, void *buf, int offs,
1706 		   int len, int even_ebadmsg);
1707 int ubifs_leb_write(struct ubifs_info *c, int lnum, const void *buf, int offs,
1708 		    int len);
1709 int ubifs_leb_change(struct ubifs_info *c, int lnum, const void *buf, int len);
1710 int ubifs_leb_unmap(struct ubifs_info *c, int lnum);
1711 int ubifs_leb_map(struct ubifs_info *c, int lnum);
1712 int ubifs_is_mapped(const struct ubifs_info *c, int lnum);
1713 int ubifs_wbuf_write_nolock(struct ubifs_wbuf *wbuf, void *buf, int len);
1714 int ubifs_wbuf_seek_nolock(struct ubifs_wbuf *wbuf, int lnum, int offs);
1715 int ubifs_wbuf_init(struct ubifs_info *c, struct ubifs_wbuf *wbuf);
1716 int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len,
1717 		    int lnum, int offs);
1718 int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len,
1719 			 int lnum, int offs);
1720 int ubifs_write_node(struct ubifs_info *c, void *node, int len, int lnum,
1721 		     int offs);
1722 int ubifs_write_node_hmac(struct ubifs_info *c, void *buf, int len, int lnum,
1723 			  int offs, int hmac_offs);
1724 int ubifs_check_node(const struct ubifs_info *c, const void *buf, int len,
1725 		     int lnum, int offs, int quiet, int must_chk_crc);
1726 void ubifs_init_node(struct ubifs_info *c, void *buf, int len, int pad);
1727 void ubifs_crc_node(struct ubifs_info *c, void *buf, int len);
1728 void ubifs_prepare_node(struct ubifs_info *c, void *buf, int len, int pad);
1729 int ubifs_prepare_node_hmac(struct ubifs_info *c, void *node, int len,
1730 			    int hmac_offs, int pad);
1731 void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last);
1732 int ubifs_io_init(struct ubifs_info *c);
1733 void ubifs_pad(const struct ubifs_info *c, void *buf, int pad);
1734 int ubifs_wbuf_sync_nolock(struct ubifs_wbuf *wbuf);
1735 int ubifs_bg_wbufs_sync(struct ubifs_info *c);
1736 void ubifs_wbuf_add_ino_nolock(struct ubifs_wbuf *wbuf, ino_t inum);
1737 int ubifs_sync_wbufs_by_inode(struct ubifs_info *c, struct inode *inode);
1738 
1739 /* scan.c */
1740 struct ubifs_scan_leb *ubifs_scan(const struct ubifs_info *c, int lnum,
1741 				  int offs, void *sbuf, int quiet);
1742 void ubifs_scan_destroy(struct ubifs_scan_leb *sleb);
1743 int ubifs_scan_a_node(const struct ubifs_info *c, void *buf, int len, int lnum,
1744 		      int offs, int quiet);
1745 struct ubifs_scan_leb *ubifs_start_scan(const struct ubifs_info *c, int lnum,
1746 					int offs, void *sbuf);
1747 void ubifs_end_scan(const struct ubifs_info *c, struct ubifs_scan_leb *sleb,
1748 		    int lnum, int offs);
1749 int ubifs_add_snod(const struct ubifs_info *c, struct ubifs_scan_leb *sleb,
1750 		   void *buf, int offs);
1751 void ubifs_scanned_corruption(const struct ubifs_info *c, int lnum, int offs,
1752 			      void *buf);
1753 
1754 /* log.c */
1755 void ubifs_add_bud(struct ubifs_info *c, struct ubifs_bud *bud);
1756 void ubifs_create_buds_lists(struct ubifs_info *c);
1757 int ubifs_add_bud_to_log(struct ubifs_info *c, int jhead, int lnum, int offs);
1758 struct ubifs_bud *ubifs_search_bud(struct ubifs_info *c, int lnum);
1759 struct ubifs_wbuf *ubifs_get_wbuf(struct ubifs_info *c, int lnum);
1760 int ubifs_log_start_commit(struct ubifs_info *c, int *ltail_lnum);
1761 int ubifs_log_end_commit(struct ubifs_info *c, int new_ltail_lnum);
1762 int ubifs_log_post_commit(struct ubifs_info *c, int old_ltail_lnum);
1763 int ubifs_consolidate_log(struct ubifs_info *c);
1764 
1765 /* journal.c */
1766 int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir,
1767 		     const struct fscrypt_name *nm, const struct inode *inode,
1768 		     int deletion, int xent);
1769 int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
1770 			 const union ubifs_key *key, const void *buf, int len);
1771 int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode);
1772 int ubifs_jnl_delete_inode(struct ubifs_info *c, const struct inode *inode);
1773 int ubifs_jnl_xrename(struct ubifs_info *c, const struct inode *fst_dir,
1774 		      const struct inode *fst_inode,
1775 		      const struct fscrypt_name *fst_nm,
1776 		      const struct inode *snd_dir,
1777 		      const struct inode *snd_inode,
1778 		      const struct fscrypt_name *snd_nm, int sync);
1779 int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
1780 		     const struct inode *old_inode,
1781 		     const struct fscrypt_name *old_nm,
1782 		     const struct inode *new_dir,
1783 		     const struct inode *new_inode,
1784 		     const struct fscrypt_name *new_nm,
1785 		     const struct inode *whiteout, int sync);
1786 int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode,
1787 		       loff_t old_size, loff_t new_size);
1788 int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host,
1789 			   const struct inode *inode, const struct fscrypt_name *nm);
1790 int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode1,
1791 			   const struct inode *inode2);
1792 
1793 /* budget.c */
1794 int ubifs_budget_space(struct ubifs_info *c, struct ubifs_budget_req *req);
1795 void ubifs_release_budget(struct ubifs_info *c, struct ubifs_budget_req *req);
1796 void ubifs_release_dirty_inode_budget(struct ubifs_info *c,
1797 				      struct ubifs_inode *ui);
1798 int ubifs_budget_inode_op(struct ubifs_info *c, struct inode *inode,
1799 			  struct ubifs_budget_req *req);
1800 void ubifs_release_ino_dirty(struct ubifs_info *c, struct inode *inode,
1801 				struct ubifs_budget_req *req);
1802 void ubifs_cancel_ino_op(struct ubifs_info *c, struct inode *inode,
1803 			 struct ubifs_budget_req *req);
1804 long long ubifs_get_free_space(struct ubifs_info *c);
1805 long long ubifs_get_free_space_nolock(struct ubifs_info *c);
1806 int ubifs_calc_min_idx_lebs(struct ubifs_info *c);
1807 void ubifs_convert_page_budget(struct ubifs_info *c);
1808 long long ubifs_reported_space(const struct ubifs_info *c, long long free);
1809 long long ubifs_calc_available(const struct ubifs_info *c, int min_idx_lebs);
1810 
1811 /* find.c */
1812 int ubifs_find_free_space(struct ubifs_info *c, int min_space, int *offs,
1813 			  int squeeze);
1814 int ubifs_find_free_leb_for_idx(struct ubifs_info *c);
1815 int ubifs_find_dirty_leb(struct ubifs_info *c, struct ubifs_lprops *ret_lp,
1816 			 int min_space, int pick_free);
1817 int ubifs_find_dirty_idx_leb(struct ubifs_info *c);
1818 int ubifs_save_dirty_idx_lnums(struct ubifs_info *c);
1819 
1820 /* tnc.c */
1821 int ubifs_lookup_level0(struct ubifs_info *c, const union ubifs_key *key,
1822 			struct ubifs_znode **zn, int *n);
1823 int ubifs_tnc_lookup_nm(struct ubifs_info *c, const union ubifs_key *key,
1824 			void *node, const struct fscrypt_name *nm);
1825 int ubifs_tnc_lookup_dh(struct ubifs_info *c, const union ubifs_key *key,
1826 			void *node, uint32_t secondary_hash);
1827 int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key,
1828 		     void *node, int *lnum, int *offs);
1829 int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum,
1830 		  int offs, int len, const u8 *hash);
1831 int ubifs_tnc_replace(struct ubifs_info *c, const union ubifs_key *key,
1832 		      int old_lnum, int old_offs, int lnum, int offs, int len);
1833 int ubifs_tnc_add_nm(struct ubifs_info *c, const union ubifs_key *key,
1834 		     int lnum, int offs, int len, const u8 *hash,
1835 		     const struct fscrypt_name *nm);
1836 int ubifs_tnc_remove(struct ubifs_info *c, const union ubifs_key *key);
1837 int ubifs_tnc_remove_nm(struct ubifs_info *c, const union ubifs_key *key,
1838 			const struct fscrypt_name *nm);
1839 int ubifs_tnc_remove_dh(struct ubifs_info *c, const union ubifs_key *key,
1840 			uint32_t cookie);
1841 int ubifs_tnc_remove_range(struct ubifs_info *c, union ubifs_key *from_key,
1842 			   union ubifs_key *to_key);
1843 int ubifs_tnc_remove_ino(struct ubifs_info *c, ino_t inum);
1844 struct ubifs_dent_node *ubifs_tnc_next_ent(struct ubifs_info *c,
1845 					   union ubifs_key *key,
1846 					   const struct fscrypt_name *nm);
1847 void ubifs_tnc_close(struct ubifs_info *c);
1848 int ubifs_tnc_has_node(struct ubifs_info *c, union ubifs_key *key, int level,
1849 		       int lnum, int offs, int is_idx);
1850 int ubifs_dirty_idx_node(struct ubifs_info *c, union ubifs_key *key, int level,
1851 			 int lnum, int offs);
1852 /* Shared by tnc.c for tnc_commit.c */
1853 void destroy_old_idx(struct ubifs_info *c);
1854 int is_idx_node_in_tnc(struct ubifs_info *c, union ubifs_key *key, int level,
1855 		       int lnum, int offs);
1856 int insert_old_idx_znode(struct ubifs_info *c, struct ubifs_znode *znode);
1857 int ubifs_tnc_get_bu_keys(struct ubifs_info *c, struct bu_info *bu);
1858 int ubifs_tnc_bulk_read(struct ubifs_info *c, struct bu_info *bu);
1859 
1860 /* tnc_misc.c */
1861 struct ubifs_znode *ubifs_tnc_levelorder_next(const struct ubifs_info *c,
1862 					      struct ubifs_znode *zr,
1863 					      struct ubifs_znode *znode);
1864 int ubifs_search_zbranch(const struct ubifs_info *c,
1865 			 const struct ubifs_znode *znode,
1866 			 const union ubifs_key *key, int *n);
1867 struct ubifs_znode *ubifs_tnc_postorder_first(struct ubifs_znode *znode);
1868 struct ubifs_znode *ubifs_tnc_postorder_next(const struct ubifs_info *c,
1869 					     struct ubifs_znode *znode);
1870 long ubifs_destroy_tnc_subtree(const struct ubifs_info *c,
1871 			       struct ubifs_znode *zr);
1872 struct ubifs_znode *ubifs_load_znode(struct ubifs_info *c,
1873 				     struct ubifs_zbranch *zbr,
1874 				     struct ubifs_znode *parent, int iip);
1875 int ubifs_tnc_read_node(struct ubifs_info *c, struct ubifs_zbranch *zbr,
1876 			void *node);
1877 
1878 /* tnc_commit.c */
1879 int ubifs_tnc_start_commit(struct ubifs_info *c, struct ubifs_zbranch *zroot);
1880 int ubifs_tnc_end_commit(struct ubifs_info *c);
1881 
1882 /* shrinker.c */
1883 unsigned long ubifs_shrink_scan(struct shrinker *shrink,
1884 				struct shrink_control *sc);
1885 unsigned long ubifs_shrink_count(struct shrinker *shrink,
1886 				 struct shrink_control *sc);
1887 
1888 /* commit.c */
1889 int ubifs_bg_thread(void *info);
1890 void ubifs_commit_required(struct ubifs_info *c);
1891 void ubifs_request_bg_commit(struct ubifs_info *c);
1892 int ubifs_run_commit(struct ubifs_info *c);
1893 void ubifs_recovery_commit(struct ubifs_info *c);
1894 int ubifs_gc_should_commit(struct ubifs_info *c);
1895 void ubifs_wait_for_commit(struct ubifs_info *c);
1896 
1897 /* master.c */
1898 int ubifs_compare_master_node(struct ubifs_info *c, void *m1, void *m2);
1899 int ubifs_read_master(struct ubifs_info *c);
1900 int ubifs_write_master(struct ubifs_info *c);
1901 
1902 /* sb.c */
1903 int ubifs_read_superblock(struct ubifs_info *c);
1904 int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup);
1905 int ubifs_fixup_free_space(struct ubifs_info *c);
1906 int ubifs_enable_encryption(struct ubifs_info *c);
1907 
1908 /* replay.c */
1909 int ubifs_validate_entry(struct ubifs_info *c,
1910 			 const struct ubifs_dent_node *dent);
1911 int ubifs_replay_journal(struct ubifs_info *c);
1912 
1913 /* gc.c */
1914 int ubifs_garbage_collect(struct ubifs_info *c, int anyway);
1915 int ubifs_gc_start_commit(struct ubifs_info *c);
1916 int ubifs_gc_end_commit(struct ubifs_info *c);
1917 void ubifs_destroy_idx_gc(struct ubifs_info *c);
1918 int ubifs_get_idx_gc_leb(struct ubifs_info *c);
1919 int ubifs_garbage_collect_leb(struct ubifs_info *c, struct ubifs_lprops *lp);
1920 
1921 /* orphan.c */
1922 int ubifs_add_orphan(struct ubifs_info *c, ino_t inum);
1923 void ubifs_delete_orphan(struct ubifs_info *c, ino_t inum);
1924 int ubifs_orphan_start_commit(struct ubifs_info *c);
1925 int ubifs_orphan_end_commit(struct ubifs_info *c);
1926 int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only);
1927 int ubifs_clear_orphans(struct ubifs_info *c);
1928 
1929 /* lpt.c */
1930 int ubifs_calc_lpt_geom(struct ubifs_info *c);
1931 int ubifs_create_dflt_lpt(struct ubifs_info *c, int *main_lebs, int lpt_first,
1932 			  int *lpt_lebs, int *big_lpt, u8 *hash);
1933 int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr);
1934 struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum);
1935 struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum);
1936 int ubifs_lpt_scan_nolock(struct ubifs_info *c, int start_lnum, int end_lnum,
1937 			  ubifs_lpt_scan_callback scan_cb, void *data);
1938 
1939 /* Shared by lpt.c for lpt_commit.c */
1940 void ubifs_pack_lsave(struct ubifs_info *c, void *buf, int *lsave);
1941 void ubifs_pack_ltab(struct ubifs_info *c, void *buf,
1942 		     struct ubifs_lpt_lprops *ltab);
1943 void ubifs_pack_pnode(struct ubifs_info *c, void *buf,
1944 		      struct ubifs_pnode *pnode);
1945 void ubifs_pack_nnode(struct ubifs_info *c, void *buf,
1946 		      struct ubifs_nnode *nnode);
1947 struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c,
1948 				    struct ubifs_nnode *parent, int iip);
1949 struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c,
1950 				    struct ubifs_nnode *parent, int iip);
1951 struct ubifs_pnode *ubifs_pnode_lookup(struct ubifs_info *c, int i);
1952 int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip);
1953 void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty);
1954 void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode);
1955 uint32_t ubifs_unpack_bits(const struct ubifs_info *c, uint8_t **addr, int *pos, int nrbits);
1956 struct ubifs_nnode *ubifs_first_nnode(struct ubifs_info *c, int *hght);
1957 /* Needed only in debugging code in lpt_commit.c */
1958 int ubifs_unpack_nnode(const struct ubifs_info *c, void *buf,
1959 		       struct ubifs_nnode *nnode);
1960 int ubifs_lpt_calc_hash(struct ubifs_info *c, u8 *hash);
1961 
1962 /* lpt_commit.c */
1963 int ubifs_lpt_start_commit(struct ubifs_info *c);
1964 int ubifs_lpt_end_commit(struct ubifs_info *c);
1965 int ubifs_lpt_post_commit(struct ubifs_info *c);
1966 void ubifs_lpt_free(struct ubifs_info *c, int wr_only);
1967 
1968 /* lprops.c */
1969 const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
1970 					   const struct ubifs_lprops *lp,
1971 					   int free, int dirty, int flags,
1972 					   int idx_gc_cnt);
1973 void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst);
1974 void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
1975 		      int cat);
1976 void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
1977 		       struct ubifs_lprops *new_lprops);
1978 void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops);
1979 int ubifs_categorize_lprops(const struct ubifs_info *c,
1980 			    const struct ubifs_lprops *lprops);
1981 int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
1982 			int flags_set, int flags_clean, int idx_gc_cnt);
1983 int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
1984 			int flags_set, int flags_clean);
1985 int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp);
1986 const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c);
1987 const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c);
1988 const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c);
1989 const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c);
1990 int ubifs_calc_dark(const struct ubifs_info *c, int spc);
1991 
1992 /* file.c */
1993 int ubifs_fsync(struct file *file, loff_t start, loff_t end, int datasync);
1994 int ubifs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
1995 		  struct iattr *attr);
1996 int ubifs_update_time(struct inode *inode, struct timespec64 *time, int flags);
1997 
1998 /* dir.c */
1999 struct inode *ubifs_new_inode(struct ubifs_info *c, struct inode *dir,
2000 			      umode_t mode);
2001 int ubifs_getattr(struct user_namespace *mnt_userns, const struct path *path, struct kstat *stat,
2002 		  u32 request_mask, unsigned int flags);
2003 int ubifs_check_dir_empty(struct inode *dir);
2004 
2005 /* xattr.c */
2006 int ubifs_xattr_set(struct inode *host, const char *name, const void *value,
2007 		    size_t size, int flags, bool check_lock);
2008 ssize_t ubifs_xattr_get(struct inode *host, const char *name, void *buf,
2009 			size_t size);
2010 
2011 #ifdef CONFIG_UBIFS_FS_XATTR
2012 extern const struct xattr_handler *ubifs_xattr_handlers[];
2013 ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size);
2014 void ubifs_evict_xattr_inode(struct ubifs_info *c, ino_t xattr_inum);
2015 int ubifs_purge_xattrs(struct inode *host);
2016 #else
2017 #define ubifs_listxattr NULL
2018 #define ubifs_xattr_handlers NULL
2019 static inline void ubifs_evict_xattr_inode(struct ubifs_info *c,
2020 					   ino_t xattr_inum) { }
2021 static inline int ubifs_purge_xattrs(struct inode *host)
2022 {
2023 	return 0;
2024 }
2025 #endif
2026 
2027 #ifdef CONFIG_UBIFS_FS_SECURITY
2028 extern int ubifs_init_security(struct inode *dentry, struct inode *inode,
2029 			const struct qstr *qstr);
2030 #else
2031 static inline int ubifs_init_security(struct inode *dentry,
2032 			struct inode *inode, const struct qstr *qstr)
2033 {
2034 	return 0;
2035 }
2036 #endif
2037 
2038 
2039 /* super.c */
2040 struct inode *ubifs_iget(struct super_block *sb, unsigned long inum);
2041 
2042 /* recovery.c */
2043 int ubifs_recover_master_node(struct ubifs_info *c);
2044 int ubifs_write_rcvrd_mst_node(struct ubifs_info *c);
2045 struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
2046 					 int offs, void *sbuf, int jhead);
2047 struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum,
2048 					     int offs, void *sbuf);
2049 int ubifs_recover_inl_heads(struct ubifs_info *c, void *sbuf);
2050 int ubifs_clean_lebs(struct ubifs_info *c, void *sbuf);
2051 int ubifs_rcvry_gc_commit(struct ubifs_info *c);
2052 int ubifs_recover_size_accum(struct ubifs_info *c, union ubifs_key *key,
2053 			     int deletion, loff_t new_size);
2054 int ubifs_recover_size(struct ubifs_info *c, bool in_place);
2055 void ubifs_destroy_size_tree(struct ubifs_info *c);
2056 
2057 /* ioctl.c */
2058 int ubifs_fileattr_get(struct dentry *dentry, struct fileattr *fa);
2059 int ubifs_fileattr_set(struct user_namespace *mnt_userns,
2060 		       struct dentry *dentry, struct fileattr *fa);
2061 long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
2062 void ubifs_set_inode_flags(struct inode *inode);
2063 #ifdef CONFIG_COMPAT
2064 long ubifs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
2065 #endif
2066 
2067 /* compressor.c */
2068 int __init ubifs_compressors_init(void);
2069 void ubifs_compressors_exit(void);
2070 void ubifs_compress(const struct ubifs_info *c, const void *in_buf, int in_len,
2071 		    void *out_buf, int *out_len, int *compr_type);
2072 int ubifs_decompress(const struct ubifs_info *c, const void *buf, int len,
2073 		     void *out, int *out_len, int compr_type);
2074 
2075 #include "debug.h"
2076 #include "misc.h"
2077 #include "key.h"
2078 
2079 #ifndef CONFIG_FS_ENCRYPTION
2080 static inline int ubifs_encrypt(const struct inode *inode,
2081 				struct ubifs_data_node *dn,
2082 				unsigned int in_len, unsigned int *out_len,
2083 				int block)
2084 {
2085 	struct ubifs_info *c = inode->i_sb->s_fs_info;
2086 	ubifs_assert(c, 0);
2087 	return -EOPNOTSUPP;
2088 }
2089 static inline int ubifs_decrypt(const struct inode *inode,
2090 				struct ubifs_data_node *dn,
2091 				unsigned int *out_len, int block)
2092 {
2093 	struct ubifs_info *c = inode->i_sb->s_fs_info;
2094 	ubifs_assert(c, 0);
2095 	return -EOPNOTSUPP;
2096 }
2097 #else
2098 /* crypto.c */
2099 int ubifs_encrypt(const struct inode *inode, struct ubifs_data_node *dn,
2100 		  unsigned int in_len, unsigned int *out_len, int block);
2101 int ubifs_decrypt(const struct inode *inode, struct ubifs_data_node *dn,
2102 		  unsigned int *out_len, int block);
2103 #endif
2104 
2105 extern const struct fscrypt_operations ubifs_crypt_operations;
2106 
2107 /* Normal UBIFS messages */
2108 __printf(2, 3)
2109 void ubifs_msg(const struct ubifs_info *c, const char *fmt, ...);
2110 __printf(2, 3)
2111 void ubifs_err(const struct ubifs_info *c, const char *fmt, ...);
2112 __printf(2, 3)
2113 void ubifs_warn(const struct ubifs_info *c, const char *fmt, ...);
2114 /*
2115  * A conditional variant of 'ubifs_err()' which doesn't output anything
2116  * if probing (ie. SB_SILENT set).
2117  */
2118 #define ubifs_errc(c, fmt, ...)						\
2119 do {									\
2120 	if (!(c)->probing)						\
2121 		ubifs_err(c, fmt, ##__VA_ARGS__);			\
2122 } while (0)
2123 
2124 #endif /* !__UBIFS_H__ */
2125