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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: Adrian Hunter
8 * Artem Bityutskiy (Битюцкий Артём)
9 */
10
11/*
12 * This file contains journal replay code. It runs when the file-system is being
13 * mounted and requires no locking.
14 *
15 * The larger is the journal, the longer it takes to scan it, so the longer it
16 * takes to mount UBIFS. This is why the journal has limited size which may be
17 * changed depending on the system requirements. But a larger journal gives
18 * faster I/O speed because it writes the index less frequently. So this is a
19 * trade-off. Also, the journal is indexed by the in-memory index (TNC), so the
20 * larger is the journal, the more memory its index may consume.
21 */
22
23#include "ubifs.h"
24#include <linux/list_sort.h>
25#include <crypto/hash.h>
26
27/**
28 * struct replay_entry - replay list entry.
29 * @lnum: logical eraseblock number of the node
30 * @offs: node offset
31 * @len: node length
32 * @deletion: non-zero if this entry corresponds to a node deletion
33 * @sqnum: node sequence number
34 * @list: links the replay list
35 * @key: node key
36 * @nm: directory entry name
37 * @old_size: truncation old size
38 * @new_size: truncation new size
39 *
40 * The replay process first scans all buds and builds the replay list, then
41 * sorts the replay list in nodes sequence number order, and then inserts all
42 * the replay entries to the TNC.
43 */
44struct replay_entry {
45 int lnum;
46 int offs;
47 int len;
48 u8 hash[UBIFS_HASH_ARR_SZ];
49 unsigned int deletion:1;
50 unsigned long long sqnum;
51 struct list_head list;
52 union ubifs_key key;
53 union {
54 struct fscrypt_name nm;
55 struct {
56 loff_t old_size;
57 loff_t new_size;
58 };
59 };
60};
61
62/**
63 * struct bud_entry - entry in the list of buds to replay.
64 * @list: next bud in the list
65 * @bud: bud description object
66 * @sqnum: reference node sequence number
67 * @free: free bytes in the bud
68 * @dirty: dirty bytes in the bud
69 */
70struct bud_entry {
71 struct list_head list;
72 struct ubifs_bud *bud;
73 unsigned long long sqnum;
74 int free;
75 int dirty;
76};
77
78/**
79 * set_bud_lprops - set free and dirty space used by a bud.
80 * @c: UBIFS file-system description object
81 * @b: bud entry which describes the bud
82 *
83 * This function makes sure the LEB properties of bud @b are set correctly
84 * after the replay. Returns zero in case of success and a negative error code
85 * in case of failure.
86 */
87static int set_bud_lprops(struct ubifs_info *c, struct bud_entry *b)
88{
89 const struct ubifs_lprops *lp;
90 int err = 0, dirty;
91
92 ubifs_get_lprops(c);
93
94 lp = ubifs_lpt_lookup_dirty(c, b->bud->lnum);
95 if (IS_ERR(lp)) {
96 err = PTR_ERR(lp);
97 goto out;
98 }
99
100 dirty = lp->dirty;
101 if (b->bud->start == 0 && (lp->free != c->leb_size || lp->dirty != 0)) {
102 /*
103 * The LEB was added to the journal with a starting offset of
104 * zero which means the LEB must have been empty. The LEB
105 * property values should be @lp->free == @c->leb_size and
106 * @lp->dirty == 0, but that is not the case. The reason is that
107 * the LEB had been garbage collected before it became the bud,
108 * and there was no commit in between. The garbage collector
109 * resets the free and dirty space without recording it
110 * anywhere except lprops, so if there was no commit then
111 * lprops does not have that information.
112 *
113 * We do not need to adjust free space because the scan has told
114 * us the exact value which is recorded in the replay entry as
115 * @b->free.
116 *
117 * However we do need to subtract from the dirty space the
118 * amount of space that the garbage collector reclaimed, which
119 * is the whole LEB minus the amount of space that was free.
120 */
121 dbg_mnt("bud LEB %d was GC'd (%d free, %d dirty)", b->bud->lnum,
122 lp->free, lp->dirty);
123 dbg_gc("bud LEB %d was GC'd (%d free, %d dirty)", b->bud->lnum,
124 lp->free, lp->dirty);
125 dirty -= c->leb_size - lp->free;
126 /*
127 * If the replay order was perfect the dirty space would now be
128 * zero. The order is not perfect because the journal heads
129 * race with each other. This is not a problem but is does mean
130 * that the dirty space may temporarily exceed c->leb_size
131 * during the replay.
132 */
133 if (dirty != 0)
134 dbg_mnt("LEB %d lp: %d free %d dirty replay: %d free %d dirty",
135 b->bud->lnum, lp->free, lp->dirty, b->free,
136 b->dirty);
137 }
138 lp = ubifs_change_lp(c, lp, b->free, dirty + b->dirty,
139 lp->flags | LPROPS_TAKEN, 0);
140 if (IS_ERR(lp)) {
141 err = PTR_ERR(lp);
142 goto out;
143 }
144
145 /* Make sure the journal head points to the latest bud */
146 err = ubifs_wbuf_seek_nolock(&c->jheads[b->bud->jhead].wbuf,
147 b->bud->lnum, c->leb_size - b->free);
148
149out:
150 ubifs_release_lprops(c);
151 return err;
152}
153
154/**
155 * set_buds_lprops - set free and dirty space for all replayed buds.
156 * @c: UBIFS file-system description object
157 *
158 * This function sets LEB properties for all replayed buds. Returns zero in
159 * case of success and a negative error code in case of failure.
160 */
161static int set_buds_lprops(struct ubifs_info *c)
162{
163 struct bud_entry *b;
164 int err;
165
166 list_for_each_entry(b, &c->replay_buds, list) {
167 err = set_bud_lprops(c, b);
168 if (err)
169 return err;
170 }
171
172 return 0;
173}
174
175/**
176 * trun_remove_range - apply a replay entry for a truncation to the TNC.
177 * @c: UBIFS file-system description object
178 * @r: replay entry of truncation
179 */
180static int trun_remove_range(struct ubifs_info *c, struct replay_entry *r)
181{
182 unsigned min_blk, max_blk;
183 union ubifs_key min_key, max_key;
184 ino_t ino;
185
186 min_blk = r->new_size / UBIFS_BLOCK_SIZE;
187 if (r->new_size & (UBIFS_BLOCK_SIZE - 1))
188 min_blk += 1;
189
190 max_blk = r->old_size / UBIFS_BLOCK_SIZE;
191 if ((r->old_size & (UBIFS_BLOCK_SIZE - 1)) == 0)
192 max_blk -= 1;
193
194 ino = key_inum(c, &r->key);
195
196 data_key_init(c, &min_key, ino, min_blk);
197 data_key_init(c, &max_key, ino, max_blk);
198
199 return ubifs_tnc_remove_range(c, &min_key, &max_key);
200}
201
202/**
203 * inode_still_linked - check whether inode in question will be re-linked.
204 * @c: UBIFS file-system description object
205 * @rino: replay entry to test
206 *
207 * O_TMPFILE files can be re-linked, this means link count goes from 0 to 1.
208 * This case needs special care, otherwise all references to the inode will
209 * be removed upon the first replay entry of an inode with link count 0
210 * is found.
211 */
212static bool inode_still_linked(struct ubifs_info *c, struct replay_entry *rino)
213{
214 struct replay_entry *r;
215
216 ubifs_assert(c, rino->deletion);
217 ubifs_assert(c, key_type(c, &rino->key) == UBIFS_INO_KEY);
218
219 /*
220 * Find the most recent entry for the inode behind @rino and check
221 * whether it is a deletion.
222 */
223 list_for_each_entry_reverse(r, &c->replay_list, list) {
224 ubifs_assert(c, r->sqnum >= rino->sqnum);
225 if (key_inum(c, &r->key) == key_inum(c, &rino->key) &&
226 key_type(c, &r->key) == UBIFS_INO_KEY)
227 return r->deletion == 0;
228
229 }
230
231 ubifs_assert(c, 0);
232 return false;
233}
234
235/**
236 * apply_replay_entry - apply a replay entry to the TNC.
237 * @c: UBIFS file-system description object
238 * @r: replay entry to apply
239 *
240 * Apply a replay entry to the TNC.
241 */
242static int apply_replay_entry(struct ubifs_info *c, struct replay_entry *r)
243{
244 int err;
245
246 dbg_mntk(&r->key, "LEB %d:%d len %d deletion %d sqnum %llu key ",
247 r->lnum, r->offs, r->len, r->deletion, r->sqnum);
248
249 if (is_hash_key(c, &r->key)) {
250 if (r->deletion)
251 err = ubifs_tnc_remove_nm(c, &r->key, &r->nm);
252 else
253 err = ubifs_tnc_add_nm(c, &r->key, r->lnum, r->offs,
254 r->len, r->hash, &r->nm);
255 } else {
256 if (r->deletion)
257 switch (key_type(c, &r->key)) {
258 case UBIFS_INO_KEY:
259 {
260 ino_t inum = key_inum(c, &r->key);
261
262 if (inode_still_linked(c, r)) {
263 err = 0;
264 break;
265 }
266
267 err = ubifs_tnc_remove_ino(c, inum);
268 break;
269 }
270 case UBIFS_TRUN_KEY:
271 err = trun_remove_range(c, r);
272 break;
273 default:
274 err = ubifs_tnc_remove(c, &r->key);
275 break;
276 }
277 else
278 err = ubifs_tnc_add(c, &r->key, r->lnum, r->offs,
279 r->len, r->hash);
280 if (err)
281 return err;
282
283 if (c->need_recovery)
284 err = ubifs_recover_size_accum(c, &r->key, r->deletion,
285 r->new_size);
286 }
287
288 return err;
289}
290
291/**
292 * replay_entries_cmp - compare 2 replay entries.
293 * @priv: UBIFS file-system description object
294 * @a: first replay entry
295 * @b: second replay entry
296 *
297 * This is a comparios function for 'list_sort()' which compares 2 replay
298 * entries @a and @b by comparing their sequence number. Returns %1 if @a has
299 * greater sequence number and %-1 otherwise.
300 */
301static int replay_entries_cmp(void *priv, const struct list_head *a,
302 const struct list_head *b)
303{
304 struct ubifs_info *c = priv;
305 struct replay_entry *ra, *rb;
306
307 cond_resched();
308 if (a == b)
309 return 0;
310
311 ra = list_entry(a, struct replay_entry, list);
312 rb = list_entry(b, struct replay_entry, list);
313 ubifs_assert(c, ra->sqnum != rb->sqnum);
314 if (ra->sqnum > rb->sqnum)
315 return 1;
316 return -1;
317}
318
319/**
320 * apply_replay_list - apply the replay list to the TNC.
321 * @c: UBIFS file-system description object
322 *
323 * Apply all entries in the replay list to the TNC. Returns zero in case of
324 * success and a negative error code in case of failure.
325 */
326static int apply_replay_list(struct ubifs_info *c)
327{
328 struct replay_entry *r;
329 int err;
330
331 list_sort(c, &c->replay_list, &replay_entries_cmp);
332
333 list_for_each_entry(r, &c->replay_list, list) {
334 cond_resched();
335
336 err = apply_replay_entry(c, r);
337 if (err)
338 return err;
339 }
340
341 return 0;
342}
343
344/**
345 * destroy_replay_list - destroy the replay.
346 * @c: UBIFS file-system description object
347 *
348 * Destroy the replay list.
349 */
350static void destroy_replay_list(struct ubifs_info *c)
351{
352 struct replay_entry *r, *tmp;
353
354 list_for_each_entry_safe(r, tmp, &c->replay_list, list) {
355 if (is_hash_key(c, &r->key))
356 kfree(fname_name(&r->nm));
357 list_del(&r->list);
358 kfree(r);
359 }
360}
361
362/**
363 * insert_node - insert a node to the replay list
364 * @c: UBIFS file-system description object
365 * @lnum: node logical eraseblock number
366 * @offs: node offset
367 * @len: node length
368 * @hash: node hash
369 * @key: node key
370 * @sqnum: sequence number
371 * @deletion: non-zero if this is a deletion
372 * @used: number of bytes in use in a LEB
373 * @old_size: truncation old size
374 * @new_size: truncation new size
375 *
376 * This function inserts a scanned non-direntry node to the replay list. The
377 * replay list contains @struct replay_entry elements, and we sort this list in
378 * sequence number order before applying it. The replay list is applied at the
379 * very end of the replay process. Since the list is sorted in sequence number
380 * order, the older modifications are applied first. This function returns zero
381 * in case of success and a negative error code in case of failure.
382 */
383static int insert_node(struct ubifs_info *c, int lnum, int offs, int len,
384 const u8 *hash, union ubifs_key *key,
385 unsigned long long sqnum, int deletion, int *used,
386 loff_t old_size, loff_t new_size)
387{
388 struct replay_entry *r;
389
390 dbg_mntk(key, "add LEB %d:%d, key ", lnum, offs);
391
392 if (key_inum(c, key) >= c->highest_inum)
393 c->highest_inum = key_inum(c, key);
394
395 r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
396 if (!r)
397 return -ENOMEM;
398
399 if (!deletion)
400 *used += ALIGN(len, 8);
401 r->lnum = lnum;
402 r->offs = offs;
403 r->len = len;
404 ubifs_copy_hash(c, hash, r->hash);
405 r->deletion = !!deletion;
406 r->sqnum = sqnum;
407 key_copy(c, key, &r->key);
408 r->old_size = old_size;
409 r->new_size = new_size;
410
411 list_add_tail(&r->list, &c->replay_list);
412 return 0;
413}
414
415/**
416 * insert_dent - insert a directory entry node into the replay list.
417 * @c: UBIFS file-system description object
418 * @lnum: node logical eraseblock number
419 * @offs: node offset
420 * @len: node length
421 * @hash: node hash
422 * @key: node key
423 * @name: directory entry name
424 * @nlen: directory entry name length
425 * @sqnum: sequence number
426 * @deletion: non-zero if this is a deletion
427 * @used: number of bytes in use in a LEB
428 *
429 * This function inserts a scanned directory entry node or an extended
430 * attribute entry to the replay list. Returns zero in case of success and a
431 * negative error code in case of failure.
432 */
433static int insert_dent(struct ubifs_info *c, int lnum, int offs, int len,
434 const u8 *hash, union ubifs_key *key,
435 const char *name, int nlen, unsigned long long sqnum,
436 int deletion, int *used)
437{
438 struct replay_entry *r;
439 char *nbuf;
440
441 dbg_mntk(key, "add LEB %d:%d, key ", lnum, offs);
442 if (key_inum(c, key) >= c->highest_inum)
443 c->highest_inum = key_inum(c, key);
444
445 r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
446 if (!r)
447 return -ENOMEM;
448
449 nbuf = kmalloc(nlen + 1, GFP_KERNEL);
450 if (!nbuf) {
451 kfree(r);
452 return -ENOMEM;
453 }
454
455 if (!deletion)
456 *used += ALIGN(len, 8);
457 r->lnum = lnum;
458 r->offs = offs;
459 r->len = len;
460 ubifs_copy_hash(c, hash, r->hash);
461 r->deletion = !!deletion;
462 r->sqnum = sqnum;
463 key_copy(c, key, &r->key);
464 fname_len(&r->nm) = nlen;
465 memcpy(nbuf, name, nlen);
466 nbuf[nlen] = '\0';
467 fname_name(&r->nm) = nbuf;
468
469 list_add_tail(&r->list, &c->replay_list);
470 return 0;
471}
472
473/**
474 * ubifs_validate_entry - validate directory or extended attribute entry node.
475 * @c: UBIFS file-system description object
476 * @dent: the node to validate
477 *
478 * This function validates directory or extended attribute entry node @dent.
479 * Returns zero if the node is all right and a %-EINVAL if not.
480 */
481int ubifs_validate_entry(struct ubifs_info *c,
482 const struct ubifs_dent_node *dent)
483{
484 int key_type = key_type_flash(c, dent->key);
485 int nlen = le16_to_cpu(dent->nlen);
486
487 if (le32_to_cpu(dent->ch.len) != nlen + UBIFS_DENT_NODE_SZ + 1 ||
488 dent->type >= UBIFS_ITYPES_CNT ||
489 nlen > UBIFS_MAX_NLEN || dent->name[nlen] != 0 ||
490 (key_type == UBIFS_XENT_KEY && strnlen(dent->name, nlen) != nlen) ||
491 le64_to_cpu(dent->inum) > MAX_INUM) {
492 ubifs_err(c, "bad %s node", key_type == UBIFS_DENT_KEY ?
493 "directory entry" : "extended attribute entry");
494 return -EINVAL;
495 }
496
497 if (key_type != UBIFS_DENT_KEY && key_type != UBIFS_XENT_KEY) {
498 ubifs_err(c, "bad key type %d", key_type);
499 return -EINVAL;
500 }
501
502 return 0;
503}
504
505/**
506 * is_last_bud - check if the bud is the last in the journal head.
507 * @c: UBIFS file-system description object
508 * @bud: bud description object
509 *
510 * This function checks if bud @bud is the last bud in its journal head. This
511 * information is then used by 'replay_bud()' to decide whether the bud can
512 * have corruptions or not. Indeed, only last buds can be corrupted by power
513 * cuts. Returns %1 if this is the last bud, and %0 if not.
514 */
515static int is_last_bud(struct ubifs_info *c, struct ubifs_bud *bud)
516{
517 struct ubifs_jhead *jh = &c->jheads[bud->jhead];
518 struct ubifs_bud *next;
519 uint32_t data;
520 int err;
521
522 if (list_is_last(&bud->list, &jh->buds_list))
523 return 1;
524
525 /*
526 * The following is a quirk to make sure we work correctly with UBIFS
527 * images used with older UBIFS.
528 *
529 * Normally, the last bud will be the last in the journal head's list
530 * of bud. However, there is one exception if the UBIFS image belongs
531 * to older UBIFS. This is fairly unlikely: one would need to use old
532 * UBIFS, then have a power cut exactly at the right point, and then
533 * try to mount this image with new UBIFS.
534 *
535 * The exception is: it is possible to have 2 buds A and B, A goes
536 * before B, and B is the last, bud B is contains no data, and bud A is
537 * corrupted at the end. The reason is that in older versions when the
538 * journal code switched the next bud (from A to B), it first added a
539 * log reference node for the new bud (B), and only after this it
540 * synchronized the write-buffer of current bud (A). But later this was
541 * changed and UBIFS started to always synchronize the write-buffer of
542 * the bud (A) before writing the log reference for the new bud (B).
543 *
544 * But because older UBIFS always synchronized A's write-buffer before
545 * writing to B, we can recognize this exceptional situation but
546 * checking the contents of bud B - if it is empty, then A can be
547 * treated as the last and we can recover it.
548 *
549 * TODO: remove this piece of code in a couple of years (today it is
550 * 16.05.2011).
551 */
552 next = list_entry(bud->list.next, struct ubifs_bud, list);
553 if (!list_is_last(&next->list, &jh->buds_list))
554 return 0;
555
556 err = ubifs_leb_read(c, next->lnum, (char *)&data, next->start, 4, 1);
557 if (err)
558 return 0;
559
560 return data == 0xFFFFFFFF;
561}
562
563/* authenticate_sleb_hash is split out for stack usage */
564static int noinline_for_stack
565authenticate_sleb_hash(struct ubifs_info *c,
566 struct shash_desc *log_hash, u8 *hash)
567{
568 SHASH_DESC_ON_STACK(hash_desc, c->hash_tfm);
569
570 hash_desc->tfm = c->hash_tfm;
571
572 ubifs_shash_copy_state(c, log_hash, hash_desc);
573 return crypto_shash_final(hash_desc, hash);
574}
575
576/**
577 * authenticate_sleb - authenticate one scan LEB
578 * @c: UBIFS file-system description object
579 * @sleb: the scan LEB to authenticate
580 * @log_hash:
581 * @is_last: if true, this is the last LEB
582 *
583 * This function iterates over the buds of a single LEB authenticating all buds
584 * with the authentication nodes on this LEB. Authentication nodes are written
585 * after some buds and contain a HMAC covering the authentication node itself
586 * and the buds between the last authentication node and the current
587 * authentication node. It can happen that the last buds cannot be authenticated
588 * because a powercut happened when some nodes were written but not the
589 * corresponding authentication node. This function returns the number of nodes
590 * that could be authenticated or a negative error code.
591 */
592static int authenticate_sleb(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
593 struct shash_desc *log_hash, int is_last)
594{
595 int n_not_auth = 0;
596 struct ubifs_scan_node *snod;
597 int n_nodes = 0;
598 int err;
599 u8 hash[UBIFS_HASH_ARR_SZ];
600 u8 hmac[UBIFS_HMAC_ARR_SZ];
601
602 if (!ubifs_authenticated(c))
603 return sleb->nodes_cnt;
604
605 list_for_each_entry(snod, &sleb->nodes, list) {
606
607 n_nodes++;
608
609 if (snod->type == UBIFS_AUTH_NODE) {
610 struct ubifs_auth_node *auth = snod->node;
611
612 err = authenticate_sleb_hash(c, log_hash, hash);
613 if (err)
614 goto out;
615
616 err = crypto_shash_tfm_digest(c->hmac_tfm, hash,
617 c->hash_len, hmac);
618 if (err)
619 goto out;
620
621 err = ubifs_check_hmac(c, auth->hmac, hmac);
622 if (err) {
623 err = -EPERM;
624 goto out;
625 }
626 n_not_auth = 0;
627 } else {
628 err = crypto_shash_update(log_hash, snod->node,
629 snod->len);
630 if (err)
631 goto out;
632 n_not_auth++;
633 }
634 }
635
636 /*
637 * A powercut can happen when some nodes were written, but not yet
638 * the corresponding authentication node. This may only happen on
639 * the last bud though.
640 */
641 if (n_not_auth) {
642 if (is_last) {
643 dbg_mnt("%d unauthenticated nodes found on LEB %d, Ignoring them",
644 n_not_auth, sleb->lnum);
645 err = 0;
646 } else {
647 dbg_mnt("%d unauthenticated nodes found on non-last LEB %d",
648 n_not_auth, sleb->lnum);
649 err = -EPERM;
650 }
651 } else {
652 err = 0;
653 }
654out:
655 return err ? err : n_nodes - n_not_auth;
656}
657
658/**
659 * replay_bud - replay a bud logical eraseblock.
660 * @c: UBIFS file-system description object
661 * @b: bud entry which describes the bud
662 *
663 * This function replays bud @bud, recovers it if needed, and adds all nodes
664 * from this bud to the replay list. Returns zero in case of success and a
665 * negative error code in case of failure.
666 */
667static int replay_bud(struct ubifs_info *c, struct bud_entry *b)
668{
669 int is_last = is_last_bud(c, b->bud);
670 int err = 0, used = 0, lnum = b->bud->lnum, offs = b->bud->start;
671 int n_nodes, n = 0;
672 struct ubifs_scan_leb *sleb;
673 struct ubifs_scan_node *snod;
674
675 dbg_mnt("replay bud LEB %d, head %d, offs %d, is_last %d",
676 lnum, b->bud->jhead, offs, is_last);
677
678 if (c->need_recovery && is_last)
679 /*
680 * Recover only last LEBs in the journal heads, because power
681 * cuts may cause corruptions only in these LEBs, because only
682 * these LEBs could possibly be written to at the power cut
683 * time.
684 */
685 sleb = ubifs_recover_leb(c, lnum, offs, c->sbuf, b->bud->jhead);
686 else
687 sleb = ubifs_scan(c, lnum, offs, c->sbuf, 0);
688 if (IS_ERR(sleb))
689 return PTR_ERR(sleb);
690
691 n_nodes = authenticate_sleb(c, sleb, b->bud->log_hash, is_last);
692 if (n_nodes < 0) {
693 err = n_nodes;
694 goto out;
695 }
696
697 ubifs_shash_copy_state(c, b->bud->log_hash,
698 c->jheads[b->bud->jhead].log_hash);
699
700 /*
701 * The bud does not have to start from offset zero - the beginning of
702 * the 'lnum' LEB may contain previously committed data. One of the
703 * things we have to do in replay is to correctly update lprops with
704 * newer information about this LEB.
705 *
706 * At this point lprops thinks that this LEB has 'c->leb_size - offs'
707 * bytes of free space because it only contain information about
708 * committed data.
709 *
710 * But we know that real amount of free space is 'c->leb_size -
711 * sleb->endpt', and the space in the 'lnum' LEB between 'offs' and
712 * 'sleb->endpt' is used by bud data. We have to correctly calculate
713 * how much of these data are dirty and update lprops with this
714 * information.
715 *
716 * The dirt in that LEB region is comprised of padding nodes, deletion
717 * nodes, truncation nodes and nodes which are obsoleted by subsequent
718 * nodes in this LEB. So instead of calculating clean space, we
719 * calculate used space ('used' variable).
720 */
721
722 list_for_each_entry(snod, &sleb->nodes, list) {
723 u8 hash[UBIFS_HASH_ARR_SZ];
724 int deletion = 0;
725
726 cond_resched();
727
728 if (snod->sqnum >= SQNUM_WATERMARK) {
729 ubifs_err(c, "file system's life ended");
730 goto out_dump;
731 }
732
733 ubifs_node_calc_hash(c, snod->node, hash);
734
735 if (snod->sqnum > c->max_sqnum)
736 c->max_sqnum = snod->sqnum;
737
738 switch (snod->type) {
739 case UBIFS_INO_NODE:
740 {
741 struct ubifs_ino_node *ino = snod->node;
742 loff_t new_size = le64_to_cpu(ino->size);
743
744 if (le32_to_cpu(ino->nlink) == 0)
745 deletion = 1;
746 err = insert_node(c, lnum, snod->offs, snod->len, hash,
747 &snod->key, snod->sqnum, deletion,
748 &used, 0, new_size);
749 break;
750 }
751 case UBIFS_DATA_NODE:
752 {
753 struct ubifs_data_node *dn = snod->node;
754 loff_t new_size = le32_to_cpu(dn->size) +
755 key_block(c, &snod->key) *
756 UBIFS_BLOCK_SIZE;
757
758 err = insert_node(c, lnum, snod->offs, snod->len, hash,
759 &snod->key, snod->sqnum, deletion,
760 &used, 0, new_size);
761 break;
762 }
763 case UBIFS_DENT_NODE:
764 case UBIFS_XENT_NODE:
765 {
766 struct ubifs_dent_node *dent = snod->node;
767
768 err = ubifs_validate_entry(c, dent);
769 if (err)
770 goto out_dump;
771
772 err = insert_dent(c, lnum, snod->offs, snod->len, hash,
773 &snod->key, dent->name,
774 le16_to_cpu(dent->nlen), snod->sqnum,
775 !le64_to_cpu(dent->inum), &used);
776 break;
777 }
778 case UBIFS_TRUN_NODE:
779 {
780 struct ubifs_trun_node *trun = snod->node;
781 loff_t old_size = le64_to_cpu(trun->old_size);
782 loff_t new_size = le64_to_cpu(trun->new_size);
783 union ubifs_key key;
784
785 /* Validate truncation node */
786 if (old_size < 0 || old_size > c->max_inode_sz ||
787 new_size < 0 || new_size > c->max_inode_sz ||
788 old_size <= new_size) {
789 ubifs_err(c, "bad truncation node");
790 goto out_dump;
791 }
792
793 /*
794 * Create a fake truncation key just to use the same
795 * functions which expect nodes to have keys.
796 */
797 trun_key_init(c, &key, le32_to_cpu(trun->inum));
798 err = insert_node(c, lnum, snod->offs, snod->len, hash,
799 &key, snod->sqnum, 1, &used,
800 old_size, new_size);
801 break;
802 }
803 case UBIFS_AUTH_NODE:
804 break;
805 default:
806 ubifs_err(c, "unexpected node type %d in bud LEB %d:%d",
807 snod->type, lnum, snod->offs);
808 err = -EINVAL;
809 goto out_dump;
810 }
811 if (err)
812 goto out;
813
814 n++;
815 if (n == n_nodes)
816 break;
817 }
818
819 ubifs_assert(c, ubifs_search_bud(c, lnum));
820 ubifs_assert(c, sleb->endpt - offs >= used);
821 ubifs_assert(c, sleb->endpt % c->min_io_size == 0);
822
823 b->dirty = sleb->endpt - offs - used;
824 b->free = c->leb_size - sleb->endpt;
825 dbg_mnt("bud LEB %d replied: dirty %d, free %d",
826 lnum, b->dirty, b->free);
827
828out:
829 ubifs_scan_destroy(sleb);
830 return err;
831
832out_dump:
833 ubifs_err(c, "bad node is at LEB %d:%d", lnum, snod->offs);
834 ubifs_dump_node(c, snod->node, c->leb_size - snod->offs);
835 ubifs_scan_destroy(sleb);
836 return -EINVAL;
837}
838
839/**
840 * replay_buds - replay all buds.
841 * @c: UBIFS file-system description object
842 *
843 * This function returns zero in case of success and a negative error code in
844 * case of failure.
845 */
846static int replay_buds(struct ubifs_info *c)
847{
848 struct bud_entry *b;
849 int err;
850 unsigned long long prev_sqnum = 0;
851
852 list_for_each_entry(b, &c->replay_buds, list) {
853 err = replay_bud(c, b);
854 if (err)
855 return err;
856
857 ubifs_assert(c, b->sqnum > prev_sqnum);
858 prev_sqnum = b->sqnum;
859 }
860
861 return 0;
862}
863
864/**
865 * destroy_bud_list - destroy the list of buds to replay.
866 * @c: UBIFS file-system description object
867 */
868static void destroy_bud_list(struct ubifs_info *c)
869{
870 struct bud_entry *b;
871
872 while (!list_empty(&c->replay_buds)) {
873 b = list_entry(c->replay_buds.next, struct bud_entry, list);
874 list_del(&b->list);
875 kfree(b);
876 }
877}
878
879/**
880 * add_replay_bud - add a bud to the list of buds to replay.
881 * @c: UBIFS file-system description object
882 * @lnum: bud logical eraseblock number to replay
883 * @offs: bud start offset
884 * @jhead: journal head to which this bud belongs
885 * @sqnum: reference node sequence number
886 *
887 * This function returns zero in case of success and a negative error code in
888 * case of failure.
889 */
890static int add_replay_bud(struct ubifs_info *c, int lnum, int offs, int jhead,
891 unsigned long long sqnum)
892{
893 struct ubifs_bud *bud;
894 struct bud_entry *b;
895 int err;
896
897 dbg_mnt("add replay bud LEB %d:%d, head %d", lnum, offs, jhead);
898
899 bud = kmalloc(sizeof(struct ubifs_bud), GFP_KERNEL);
900 if (!bud)
901 return -ENOMEM;
902
903 b = kmalloc(sizeof(struct bud_entry), GFP_KERNEL);
904 if (!b) {
905 err = -ENOMEM;
906 goto out;
907 }
908
909 bud->lnum = lnum;
910 bud->start = offs;
911 bud->jhead = jhead;
912 bud->log_hash = ubifs_hash_get_desc(c);
913 if (IS_ERR(bud->log_hash)) {
914 err = PTR_ERR(bud->log_hash);
915 goto out;
916 }
917
918 ubifs_shash_copy_state(c, c->log_hash, bud->log_hash);
919
920 ubifs_add_bud(c, bud);
921
922 b->bud = bud;
923 b->sqnum = sqnum;
924 list_add_tail(&b->list, &c->replay_buds);
925
926 return 0;
927out:
928 kfree(bud);
929 kfree(b);
930
931 return err;
932}
933
934/**
935 * validate_ref - validate a reference node.
936 * @c: UBIFS file-system description object
937 * @ref: the reference node to validate
938 *
939 * This function returns %1 if a bud reference already exists for the LEB. %0 is
940 * returned if the reference node is new, otherwise %-EINVAL is returned if
941 * validation failed.
942 */
943static int validate_ref(struct ubifs_info *c, const struct ubifs_ref_node *ref)
944{
945 struct ubifs_bud *bud;
946 int lnum = le32_to_cpu(ref->lnum);
947 unsigned int offs = le32_to_cpu(ref->offs);
948 unsigned int jhead = le32_to_cpu(ref->jhead);
949
950 /*
951 * ref->offs may point to the end of LEB when the journal head points
952 * to the end of LEB and we write reference node for it during commit.
953 * So this is why we require 'offs > c->leb_size'.
954 */
955 if (jhead >= c->jhead_cnt || lnum >= c->leb_cnt ||
956 lnum < c->main_first || offs > c->leb_size ||
957 offs & (c->min_io_size - 1))
958 return -EINVAL;
959
960 /* Make sure we have not already looked at this bud */
961 bud = ubifs_search_bud(c, lnum);
962 if (bud) {
963 if (bud->jhead == jhead && bud->start <= offs)
964 return 1;
965 ubifs_err(c, "bud at LEB %d:%d was already referred", lnum, offs);
966 return -EINVAL;
967 }
968
969 return 0;
970}
971
972/**
973 * replay_log_leb - replay a log logical eraseblock.
974 * @c: UBIFS file-system description object
975 * @lnum: log logical eraseblock to replay
976 * @offs: offset to start replaying from
977 * @sbuf: scan buffer
978 *
979 * This function replays a log LEB and returns zero in case of success, %1 if
980 * this is the last LEB in the log, and a negative error code in case of
981 * failure.
982 */
983static int replay_log_leb(struct ubifs_info *c, int lnum, int offs, void *sbuf)
984{
985 int err;
986 struct ubifs_scan_leb *sleb;
987 struct ubifs_scan_node *snod;
988 const struct ubifs_cs_node *node;
989
990 dbg_mnt("replay log LEB %d:%d", lnum, offs);
991 sleb = ubifs_scan(c, lnum, offs, sbuf, c->need_recovery);
992 if (IS_ERR(sleb)) {
993 if (PTR_ERR(sleb) != -EUCLEAN || !c->need_recovery)
994 return PTR_ERR(sleb);
995 /*
996 * Note, the below function will recover this log LEB only if
997 * it is the last, because unclean reboots can possibly corrupt
998 * only the tail of the log.
999 */
1000 sleb = ubifs_recover_log_leb(c, lnum, offs, sbuf);
1001 if (IS_ERR(sleb))
1002 return PTR_ERR(sleb);
1003 }
1004
1005 if (sleb->nodes_cnt == 0) {
1006 err = 1;
1007 goto out;
1008 }
1009
1010 node = sleb->buf;
1011 snod = list_entry(sleb->nodes.next, struct ubifs_scan_node, list);
1012 if (c->cs_sqnum == 0) {
1013 /*
1014 * This is the first log LEB we are looking at, make sure that
1015 * the first node is a commit start node. Also record its
1016 * sequence number so that UBIFS can determine where the log
1017 * ends, because all nodes which were have higher sequence
1018 * numbers.
1019 */
1020 if (snod->type != UBIFS_CS_NODE) {
1021 ubifs_err(c, "first log node at LEB %d:%d is not CS node",
1022 lnum, offs);
1023 goto out_dump;
1024 }
1025 if (le64_to_cpu(node->cmt_no) != c->cmt_no) {
1026 ubifs_err(c, "first CS node at LEB %d:%d has wrong commit number %llu expected %llu",
1027 lnum, offs,
1028 (unsigned long long)le64_to_cpu(node->cmt_no),
1029 c->cmt_no);
1030 goto out_dump;
1031 }
1032
1033 c->cs_sqnum = le64_to_cpu(node->ch.sqnum);
1034 dbg_mnt("commit start sqnum %llu", c->cs_sqnum);
1035
1036 err = ubifs_shash_init(c, c->log_hash);
1037 if (err)
1038 goto out;
1039
1040 err = ubifs_shash_update(c, c->log_hash, node, UBIFS_CS_NODE_SZ);
1041 if (err < 0)
1042 goto out;
1043 }
1044
1045 if (snod->sqnum < c->cs_sqnum) {
1046 /*
1047 * This means that we reached end of log and now
1048 * look to the older log data, which was already
1049 * committed but the eraseblock was not erased (UBIFS
1050 * only un-maps it). So this basically means we have to
1051 * exit with "end of log" code.
1052 */
1053 err = 1;
1054 goto out;
1055 }
1056
1057 /* Make sure the first node sits at offset zero of the LEB */
1058 if (snod->offs != 0) {
1059 ubifs_err(c, "first node is not at zero offset");
1060 goto out_dump;
1061 }
1062
1063 list_for_each_entry(snod, &sleb->nodes, list) {
1064 cond_resched();
1065
1066 if (snod->sqnum >= SQNUM_WATERMARK) {
1067 ubifs_err(c, "file system's life ended");
1068 goto out_dump;
1069 }
1070
1071 if (snod->sqnum < c->cs_sqnum) {
1072 ubifs_err(c, "bad sqnum %llu, commit sqnum %llu",
1073 snod->sqnum, c->cs_sqnum);
1074 goto out_dump;
1075 }
1076
1077 if (snod->sqnum > c->max_sqnum)
1078 c->max_sqnum = snod->sqnum;
1079
1080 switch (snod->type) {
1081 case UBIFS_REF_NODE: {
1082 const struct ubifs_ref_node *ref = snod->node;
1083
1084 err = validate_ref(c, ref);
1085 if (err == 1)
1086 break; /* Already have this bud */
1087 if (err)
1088 goto out_dump;
1089
1090 err = ubifs_shash_update(c, c->log_hash, ref,
1091 UBIFS_REF_NODE_SZ);
1092 if (err)
1093 goto out;
1094
1095 err = add_replay_bud(c, le32_to_cpu(ref->lnum),
1096 le32_to_cpu(ref->offs),
1097 le32_to_cpu(ref->jhead),
1098 snod->sqnum);
1099 if (err)
1100 goto out;
1101
1102 break;
1103 }
1104 case UBIFS_CS_NODE:
1105 /* Make sure it sits at the beginning of LEB */
1106 if (snod->offs != 0) {
1107 ubifs_err(c, "unexpected node in log");
1108 goto out_dump;
1109 }
1110 break;
1111 default:
1112 ubifs_err(c, "unexpected node in log");
1113 goto out_dump;
1114 }
1115 }
1116
1117 if (sleb->endpt || c->lhead_offs >= c->leb_size) {
1118 c->lhead_lnum = lnum;
1119 c->lhead_offs = sleb->endpt;
1120 }
1121
1122 err = !sleb->endpt;
1123out:
1124 ubifs_scan_destroy(sleb);
1125 return err;
1126
1127out_dump:
1128 ubifs_err(c, "log error detected while replaying the log at LEB %d:%d",
1129 lnum, offs + snod->offs);
1130 ubifs_dump_node(c, snod->node, c->leb_size - snod->offs);
1131 ubifs_scan_destroy(sleb);
1132 return -EINVAL;
1133}
1134
1135/**
1136 * take_ihead - update the status of the index head in lprops to 'taken'.
1137 * @c: UBIFS file-system description object
1138 *
1139 * This function returns the amount of free space in the index head LEB or a
1140 * negative error code.
1141 */
1142static int take_ihead(struct ubifs_info *c)
1143{
1144 const struct ubifs_lprops *lp;
1145 int err, free;
1146
1147 ubifs_get_lprops(c);
1148
1149 lp = ubifs_lpt_lookup_dirty(c, c->ihead_lnum);
1150 if (IS_ERR(lp)) {
1151 err = PTR_ERR(lp);
1152 goto out;
1153 }
1154
1155 free = lp->free;
1156
1157 lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC,
1158 lp->flags | LPROPS_TAKEN, 0);
1159 if (IS_ERR(lp)) {
1160 err = PTR_ERR(lp);
1161 goto out;
1162 }
1163
1164 err = free;
1165out:
1166 ubifs_release_lprops(c);
1167 return err;
1168}
1169
1170/**
1171 * ubifs_replay_journal - replay journal.
1172 * @c: UBIFS file-system description object
1173 *
1174 * This function scans the journal, replays and cleans it up. It makes sure all
1175 * memory data structures related to uncommitted journal are built (dirty TNC
1176 * tree, tree of buds, modified lprops, etc).
1177 */
1178int ubifs_replay_journal(struct ubifs_info *c)
1179{
1180 int err, lnum, free;
1181
1182 BUILD_BUG_ON(UBIFS_TRUN_KEY > 5);
1183
1184 /* Update the status of the index head in lprops to 'taken' */
1185 free = take_ihead(c);
1186 if (free < 0)
1187 return free; /* Error code */
1188
1189 if (c->ihead_offs != c->leb_size - free) {
1190 ubifs_err(c, "bad index head LEB %d:%d", c->ihead_lnum,
1191 c->ihead_offs);
1192 return -EINVAL;
1193 }
1194
1195 dbg_mnt("start replaying the journal");
1196 c->replaying = 1;
1197 lnum = c->ltail_lnum = c->lhead_lnum;
1198
1199 do {
1200 err = replay_log_leb(c, lnum, 0, c->sbuf);
1201 if (err == 1) {
1202 if (lnum != c->lhead_lnum)
1203 /* We hit the end of the log */
1204 break;
1205
1206 /*
1207 * The head of the log must always start with the
1208 * "commit start" node on a properly formatted UBIFS.
1209 * But we found no nodes at all, which means that
1210 * something went wrong and we cannot proceed mounting
1211 * the file-system.
1212 */
1213 ubifs_err(c, "no UBIFS nodes found at the log head LEB %d:%d, possibly corrupted",
1214 lnum, 0);
1215 err = -EINVAL;
1216 }
1217 if (err)
1218 goto out;
1219 lnum = ubifs_next_log_lnum(c, lnum);
1220 } while (lnum != c->ltail_lnum);
1221
1222 err = replay_buds(c);
1223 if (err)
1224 goto out;
1225
1226 err = apply_replay_list(c);
1227 if (err)
1228 goto out;
1229
1230 err = set_buds_lprops(c);
1231 if (err)
1232 goto out;
1233
1234 /*
1235 * UBIFS budgeting calculations use @c->bi.uncommitted_idx variable
1236 * to roughly estimate index growth. Things like @c->bi.min_idx_lebs
1237 * depend on it. This means we have to initialize it to make sure
1238 * budgeting works properly.
1239 */
1240 c->bi.uncommitted_idx = atomic_long_read(&c->dirty_zn_cnt);
1241 c->bi.uncommitted_idx *= c->max_idx_node_sz;
1242
1243 ubifs_assert(c, c->bud_bytes <= c->max_bud_bytes || c->need_recovery);
1244 dbg_mnt("finished, log head LEB %d:%d, max_sqnum %llu, highest_inum %lu",
1245 c->lhead_lnum, c->lhead_offs, c->max_sqnum,
1246 (unsigned long)c->highest_inum);
1247out:
1248 destroy_replay_list(c);
1249 destroy_bud_list(c);
1250 c->replaying = 0;
1251 return err;
1252}
1/*
2 * This file is part of UBIFS.
3 *
4 * Copyright (C) 2006-2008 Nokia Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published by
8 * the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc., 51
17 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 * Authors: Adrian Hunter
20 * Artem Bityutskiy (Битюцкий Артём)
21 */
22
23/*
24 * This file contains journal replay code. It runs when the file-system is being
25 * mounted and requires no locking.
26 *
27 * The larger is the journal, the longer it takes to scan it, so the longer it
28 * takes to mount UBIFS. This is why the journal has limited size which may be
29 * changed depending on the system requirements. But a larger journal gives
30 * faster I/O speed because it writes the index less frequently. So this is a
31 * trade-off. Also, the journal is indexed by the in-memory index (TNC), so the
32 * larger is the journal, the more memory its index may consume.
33 */
34
35#include "ubifs.h"
36#include <linux/list_sort.h>
37
38/**
39 * struct replay_entry - replay list entry.
40 * @lnum: logical eraseblock number of the node
41 * @offs: node offset
42 * @len: node length
43 * @deletion: non-zero if this entry corresponds to a node deletion
44 * @sqnum: node sequence number
45 * @list: links the replay list
46 * @key: node key
47 * @nm: directory entry name
48 * @old_size: truncation old size
49 * @new_size: truncation new size
50 *
51 * The replay process first scans all buds and builds the replay list, then
52 * sorts the replay list in nodes sequence number order, and then inserts all
53 * the replay entries to the TNC.
54 */
55struct replay_entry {
56 int lnum;
57 int offs;
58 int len;
59 unsigned int deletion:1;
60 unsigned long long sqnum;
61 struct list_head list;
62 union ubifs_key key;
63 union {
64 struct qstr nm;
65 struct {
66 loff_t old_size;
67 loff_t new_size;
68 };
69 };
70};
71
72/**
73 * struct bud_entry - entry in the list of buds to replay.
74 * @list: next bud in the list
75 * @bud: bud description object
76 * @sqnum: reference node sequence number
77 * @free: free bytes in the bud
78 * @dirty: dirty bytes in the bud
79 */
80struct bud_entry {
81 struct list_head list;
82 struct ubifs_bud *bud;
83 unsigned long long sqnum;
84 int free;
85 int dirty;
86};
87
88/**
89 * set_bud_lprops - set free and dirty space used by a bud.
90 * @c: UBIFS file-system description object
91 * @b: bud entry which describes the bud
92 *
93 * This function makes sure the LEB properties of bud @b are set correctly
94 * after the replay. Returns zero in case of success and a negative error code
95 * in case of failure.
96 */
97static int set_bud_lprops(struct ubifs_info *c, struct bud_entry *b)
98{
99 const struct ubifs_lprops *lp;
100 int err = 0, dirty;
101
102 ubifs_get_lprops(c);
103
104 lp = ubifs_lpt_lookup_dirty(c, b->bud->lnum);
105 if (IS_ERR(lp)) {
106 err = PTR_ERR(lp);
107 goto out;
108 }
109
110 dirty = lp->dirty;
111 if (b->bud->start == 0 && (lp->free != c->leb_size || lp->dirty != 0)) {
112 /*
113 * The LEB was added to the journal with a starting offset of
114 * zero which means the LEB must have been empty. The LEB
115 * property values should be @lp->free == @c->leb_size and
116 * @lp->dirty == 0, but that is not the case. The reason is that
117 * the LEB had been garbage collected before it became the bud,
118 * and there was not commit inbetween. The garbage collector
119 * resets the free and dirty space without recording it
120 * anywhere except lprops, so if there was no commit then
121 * lprops does not have that information.
122 *
123 * We do not need to adjust free space because the scan has told
124 * us the exact value which is recorded in the replay entry as
125 * @b->free.
126 *
127 * However we do need to subtract from the dirty space the
128 * amount of space that the garbage collector reclaimed, which
129 * is the whole LEB minus the amount of space that was free.
130 */
131 dbg_mnt("bud LEB %d was GC'd (%d free, %d dirty)", b->bud->lnum,
132 lp->free, lp->dirty);
133 dbg_gc("bud LEB %d was GC'd (%d free, %d dirty)", b->bud->lnum,
134 lp->free, lp->dirty);
135 dirty -= c->leb_size - lp->free;
136 /*
137 * If the replay order was perfect the dirty space would now be
138 * zero. The order is not perfect because the journal heads
139 * race with each other. This is not a problem but is does mean
140 * that the dirty space may temporarily exceed c->leb_size
141 * during the replay.
142 */
143 if (dirty != 0)
144 dbg_msg("LEB %d lp: %d free %d dirty "
145 "replay: %d free %d dirty", b->bud->lnum,
146 lp->free, lp->dirty, b->free, b->dirty);
147 }
148 lp = ubifs_change_lp(c, lp, b->free, dirty + b->dirty,
149 lp->flags | LPROPS_TAKEN, 0);
150 if (IS_ERR(lp)) {
151 err = PTR_ERR(lp);
152 goto out;
153 }
154
155 /* Make sure the journal head points to the latest bud */
156 err = ubifs_wbuf_seek_nolock(&c->jheads[b->bud->jhead].wbuf,
157 b->bud->lnum, c->leb_size - b->free);
158
159out:
160 ubifs_release_lprops(c);
161 return err;
162}
163
164/**
165 * set_buds_lprops - set free and dirty space for all replayed buds.
166 * @c: UBIFS file-system description object
167 *
168 * This function sets LEB properties for all replayed buds. Returns zero in
169 * case of success and a negative error code in case of failure.
170 */
171static int set_buds_lprops(struct ubifs_info *c)
172{
173 struct bud_entry *b;
174 int err;
175
176 list_for_each_entry(b, &c->replay_buds, list) {
177 err = set_bud_lprops(c, b);
178 if (err)
179 return err;
180 }
181
182 return 0;
183}
184
185/**
186 * trun_remove_range - apply a replay entry for a truncation to the TNC.
187 * @c: UBIFS file-system description object
188 * @r: replay entry of truncation
189 */
190static int trun_remove_range(struct ubifs_info *c, struct replay_entry *r)
191{
192 unsigned min_blk, max_blk;
193 union ubifs_key min_key, max_key;
194 ino_t ino;
195
196 min_blk = r->new_size / UBIFS_BLOCK_SIZE;
197 if (r->new_size & (UBIFS_BLOCK_SIZE - 1))
198 min_blk += 1;
199
200 max_blk = r->old_size / UBIFS_BLOCK_SIZE;
201 if ((r->old_size & (UBIFS_BLOCK_SIZE - 1)) == 0)
202 max_blk -= 1;
203
204 ino = key_inum(c, &r->key);
205
206 data_key_init(c, &min_key, ino, min_blk);
207 data_key_init(c, &max_key, ino, max_blk);
208
209 return ubifs_tnc_remove_range(c, &min_key, &max_key);
210}
211
212/**
213 * apply_replay_entry - apply a replay entry to the TNC.
214 * @c: UBIFS file-system description object
215 * @r: replay entry to apply
216 *
217 * Apply a replay entry to the TNC.
218 */
219static int apply_replay_entry(struct ubifs_info *c, struct replay_entry *r)
220{
221 int err;
222
223 dbg_mntk(&r->key, "LEB %d:%d len %d deletion %d sqnum %llu key ",
224 r->lnum, r->offs, r->len, r->deletion, r->sqnum);
225
226 /* Set c->replay_sqnum to help deal with dangling branches. */
227 c->replay_sqnum = r->sqnum;
228
229 if (is_hash_key(c, &r->key)) {
230 if (r->deletion)
231 err = ubifs_tnc_remove_nm(c, &r->key, &r->nm);
232 else
233 err = ubifs_tnc_add_nm(c, &r->key, r->lnum, r->offs,
234 r->len, &r->nm);
235 } else {
236 if (r->deletion)
237 switch (key_type(c, &r->key)) {
238 case UBIFS_INO_KEY:
239 {
240 ino_t inum = key_inum(c, &r->key);
241
242 err = ubifs_tnc_remove_ino(c, inum);
243 break;
244 }
245 case UBIFS_TRUN_KEY:
246 err = trun_remove_range(c, r);
247 break;
248 default:
249 err = ubifs_tnc_remove(c, &r->key);
250 break;
251 }
252 else
253 err = ubifs_tnc_add(c, &r->key, r->lnum, r->offs,
254 r->len);
255 if (err)
256 return err;
257
258 if (c->need_recovery)
259 err = ubifs_recover_size_accum(c, &r->key, r->deletion,
260 r->new_size);
261 }
262
263 return err;
264}
265
266/**
267 * replay_entries_cmp - compare 2 replay entries.
268 * @priv: UBIFS file-system description object
269 * @a: first replay entry
270 * @a: second replay entry
271 *
272 * This is a comparios function for 'list_sort()' which compares 2 replay
273 * entries @a and @b by comparing their sequence numer. Returns %1 if @a has
274 * greater sequence number and %-1 otherwise.
275 */
276static int replay_entries_cmp(void *priv, struct list_head *a,
277 struct list_head *b)
278{
279 struct replay_entry *ra, *rb;
280
281 cond_resched();
282 if (a == b)
283 return 0;
284
285 ra = list_entry(a, struct replay_entry, list);
286 rb = list_entry(b, struct replay_entry, list);
287 ubifs_assert(ra->sqnum != rb->sqnum);
288 if (ra->sqnum > rb->sqnum)
289 return 1;
290 return -1;
291}
292
293/**
294 * apply_replay_list - apply the replay list to the TNC.
295 * @c: UBIFS file-system description object
296 *
297 * Apply all entries in the replay list to the TNC. Returns zero in case of
298 * success and a negative error code in case of failure.
299 */
300static int apply_replay_list(struct ubifs_info *c)
301{
302 struct replay_entry *r;
303 int err;
304
305 list_sort(c, &c->replay_list, &replay_entries_cmp);
306
307 list_for_each_entry(r, &c->replay_list, list) {
308 cond_resched();
309
310 err = apply_replay_entry(c, r);
311 if (err)
312 return err;
313 }
314
315 return 0;
316}
317
318/**
319 * destroy_replay_list - destroy the replay.
320 * @c: UBIFS file-system description object
321 *
322 * Destroy the replay list.
323 */
324static void destroy_replay_list(struct ubifs_info *c)
325{
326 struct replay_entry *r, *tmp;
327
328 list_for_each_entry_safe(r, tmp, &c->replay_list, list) {
329 if (is_hash_key(c, &r->key))
330 kfree(r->nm.name);
331 list_del(&r->list);
332 kfree(r);
333 }
334}
335
336/**
337 * insert_node - insert a node to the replay list
338 * @c: UBIFS file-system description object
339 * @lnum: node logical eraseblock number
340 * @offs: node offset
341 * @len: node length
342 * @key: node key
343 * @sqnum: sequence number
344 * @deletion: non-zero if this is a deletion
345 * @used: number of bytes in use in a LEB
346 * @old_size: truncation old size
347 * @new_size: truncation new size
348 *
349 * This function inserts a scanned non-direntry node to the replay list. The
350 * replay list contains @struct replay_entry elements, and we sort this list in
351 * sequence number order before applying it. The replay list is applied at the
352 * very end of the replay process. Since the list is sorted in sequence number
353 * order, the older modifications are applied first. This function returns zero
354 * in case of success and a negative error code in case of failure.
355 */
356static int insert_node(struct ubifs_info *c, int lnum, int offs, int len,
357 union ubifs_key *key, unsigned long long sqnum,
358 int deletion, int *used, loff_t old_size,
359 loff_t new_size)
360{
361 struct replay_entry *r;
362
363 dbg_mntk(key, "add LEB %d:%d, key ", lnum, offs);
364
365 if (key_inum(c, key) >= c->highest_inum)
366 c->highest_inum = key_inum(c, key);
367
368 r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
369 if (!r)
370 return -ENOMEM;
371
372 if (!deletion)
373 *used += ALIGN(len, 8);
374 r->lnum = lnum;
375 r->offs = offs;
376 r->len = len;
377 r->deletion = !!deletion;
378 r->sqnum = sqnum;
379 key_copy(c, key, &r->key);
380 r->old_size = old_size;
381 r->new_size = new_size;
382
383 list_add_tail(&r->list, &c->replay_list);
384 return 0;
385}
386
387/**
388 * insert_dent - insert a directory entry node into the replay list.
389 * @c: UBIFS file-system description object
390 * @lnum: node logical eraseblock number
391 * @offs: node offset
392 * @len: node length
393 * @key: node key
394 * @name: directory entry name
395 * @nlen: directory entry name length
396 * @sqnum: sequence number
397 * @deletion: non-zero if this is a deletion
398 * @used: number of bytes in use in a LEB
399 *
400 * This function inserts a scanned directory entry node or an extended
401 * attribute entry to the replay list. Returns zero in case of success and a
402 * negative error code in case of failure.
403 */
404static int insert_dent(struct ubifs_info *c, int lnum, int offs, int len,
405 union ubifs_key *key, const char *name, int nlen,
406 unsigned long long sqnum, int deletion, int *used)
407{
408 struct replay_entry *r;
409 char *nbuf;
410
411 dbg_mntk(key, "add LEB %d:%d, key ", lnum, offs);
412 if (key_inum(c, key) >= c->highest_inum)
413 c->highest_inum = key_inum(c, key);
414
415 r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
416 if (!r)
417 return -ENOMEM;
418
419 nbuf = kmalloc(nlen + 1, GFP_KERNEL);
420 if (!nbuf) {
421 kfree(r);
422 return -ENOMEM;
423 }
424
425 if (!deletion)
426 *used += ALIGN(len, 8);
427 r->lnum = lnum;
428 r->offs = offs;
429 r->len = len;
430 r->deletion = !!deletion;
431 r->sqnum = sqnum;
432 key_copy(c, key, &r->key);
433 r->nm.len = nlen;
434 memcpy(nbuf, name, nlen);
435 nbuf[nlen] = '\0';
436 r->nm.name = nbuf;
437
438 list_add_tail(&r->list, &c->replay_list);
439 return 0;
440}
441
442/**
443 * ubifs_validate_entry - validate directory or extended attribute entry node.
444 * @c: UBIFS file-system description object
445 * @dent: the node to validate
446 *
447 * This function validates directory or extended attribute entry node @dent.
448 * Returns zero if the node is all right and a %-EINVAL if not.
449 */
450int ubifs_validate_entry(struct ubifs_info *c,
451 const struct ubifs_dent_node *dent)
452{
453 int key_type = key_type_flash(c, dent->key);
454 int nlen = le16_to_cpu(dent->nlen);
455
456 if (le32_to_cpu(dent->ch.len) != nlen + UBIFS_DENT_NODE_SZ + 1 ||
457 dent->type >= UBIFS_ITYPES_CNT ||
458 nlen > UBIFS_MAX_NLEN || dent->name[nlen] != 0 ||
459 strnlen(dent->name, nlen) != nlen ||
460 le64_to_cpu(dent->inum) > MAX_INUM) {
461 ubifs_err("bad %s node", key_type == UBIFS_DENT_KEY ?
462 "directory entry" : "extended attribute entry");
463 return -EINVAL;
464 }
465
466 if (key_type != UBIFS_DENT_KEY && key_type != UBIFS_XENT_KEY) {
467 ubifs_err("bad key type %d", key_type);
468 return -EINVAL;
469 }
470
471 return 0;
472}
473
474/**
475 * is_last_bud - check if the bud is the last in the journal head.
476 * @c: UBIFS file-system description object
477 * @bud: bud description object
478 *
479 * This function checks if bud @bud is the last bud in its journal head. This
480 * information is then used by 'replay_bud()' to decide whether the bud can
481 * have corruptions or not. Indeed, only last buds can be corrupted by power
482 * cuts. Returns %1 if this is the last bud, and %0 if not.
483 */
484static int is_last_bud(struct ubifs_info *c, struct ubifs_bud *bud)
485{
486 struct ubifs_jhead *jh = &c->jheads[bud->jhead];
487 struct ubifs_bud *next;
488 uint32_t data;
489 int err;
490
491 if (list_is_last(&bud->list, &jh->buds_list))
492 return 1;
493
494 /*
495 * The following is a quirk to make sure we work correctly with UBIFS
496 * images used with older UBIFS.
497 *
498 * Normally, the last bud will be the last in the journal head's list
499 * of bud. However, there is one exception if the UBIFS image belongs
500 * to older UBIFS. This is fairly unlikely: one would need to use old
501 * UBIFS, then have a power cut exactly at the right point, and then
502 * try to mount this image with new UBIFS.
503 *
504 * The exception is: it is possible to have 2 buds A and B, A goes
505 * before B, and B is the last, bud B is contains no data, and bud A is
506 * corrupted at the end. The reason is that in older versions when the
507 * journal code switched the next bud (from A to B), it first added a
508 * log reference node for the new bud (B), and only after this it
509 * synchronized the write-buffer of current bud (A). But later this was
510 * changed and UBIFS started to always synchronize the write-buffer of
511 * the bud (A) before writing the log reference for the new bud (B).
512 *
513 * But because older UBIFS always synchronized A's write-buffer before
514 * writing to B, we can recognize this exceptional situation but
515 * checking the contents of bud B - if it is empty, then A can be
516 * treated as the last and we can recover it.
517 *
518 * TODO: remove this piece of code in a couple of years (today it is
519 * 16.05.2011).
520 */
521 next = list_entry(bud->list.next, struct ubifs_bud, list);
522 if (!list_is_last(&next->list, &jh->buds_list))
523 return 0;
524
525 err = ubifs_leb_read(c, next->lnum, (char *)&data, next->start, 4, 1);
526 if (err)
527 return 0;
528
529 return data == 0xFFFFFFFF;
530}
531
532/**
533 * replay_bud - replay a bud logical eraseblock.
534 * @c: UBIFS file-system description object
535 * @b: bud entry which describes the bud
536 *
537 * This function replays bud @bud, recovers it if needed, and adds all nodes
538 * from this bud to the replay list. Returns zero in case of success and a
539 * negative error code in case of failure.
540 */
541static int replay_bud(struct ubifs_info *c, struct bud_entry *b)
542{
543 int is_last = is_last_bud(c, b->bud);
544 int err = 0, used = 0, lnum = b->bud->lnum, offs = b->bud->start;
545 struct ubifs_scan_leb *sleb;
546 struct ubifs_scan_node *snod;
547
548 dbg_mnt("replay bud LEB %d, head %d, offs %d, is_last %d",
549 lnum, b->bud->jhead, offs, is_last);
550
551 if (c->need_recovery && is_last)
552 /*
553 * Recover only last LEBs in the journal heads, because power
554 * cuts may cause corruptions only in these LEBs, because only
555 * these LEBs could possibly be written to at the power cut
556 * time.
557 */
558 sleb = ubifs_recover_leb(c, lnum, offs, c->sbuf, b->bud->jhead);
559 else
560 sleb = ubifs_scan(c, lnum, offs, c->sbuf, 0);
561 if (IS_ERR(sleb))
562 return PTR_ERR(sleb);
563
564 /*
565 * The bud does not have to start from offset zero - the beginning of
566 * the 'lnum' LEB may contain previously committed data. One of the
567 * things we have to do in replay is to correctly update lprops with
568 * newer information about this LEB.
569 *
570 * At this point lprops thinks that this LEB has 'c->leb_size - offs'
571 * bytes of free space because it only contain information about
572 * committed data.
573 *
574 * But we know that real amount of free space is 'c->leb_size -
575 * sleb->endpt', and the space in the 'lnum' LEB between 'offs' and
576 * 'sleb->endpt' is used by bud data. We have to correctly calculate
577 * how much of these data are dirty and update lprops with this
578 * information.
579 *
580 * The dirt in that LEB region is comprised of padding nodes, deletion
581 * nodes, truncation nodes and nodes which are obsoleted by subsequent
582 * nodes in this LEB. So instead of calculating clean space, we
583 * calculate used space ('used' variable).
584 */
585
586 list_for_each_entry(snod, &sleb->nodes, list) {
587 int deletion = 0;
588
589 cond_resched();
590
591 if (snod->sqnum >= SQNUM_WATERMARK) {
592 ubifs_err("file system's life ended");
593 goto out_dump;
594 }
595
596 if (snod->sqnum > c->max_sqnum)
597 c->max_sqnum = snod->sqnum;
598
599 switch (snod->type) {
600 case UBIFS_INO_NODE:
601 {
602 struct ubifs_ino_node *ino = snod->node;
603 loff_t new_size = le64_to_cpu(ino->size);
604
605 if (le32_to_cpu(ino->nlink) == 0)
606 deletion = 1;
607 err = insert_node(c, lnum, snod->offs, snod->len,
608 &snod->key, snod->sqnum, deletion,
609 &used, 0, new_size);
610 break;
611 }
612 case UBIFS_DATA_NODE:
613 {
614 struct ubifs_data_node *dn = snod->node;
615 loff_t new_size = le32_to_cpu(dn->size) +
616 key_block(c, &snod->key) *
617 UBIFS_BLOCK_SIZE;
618
619 err = insert_node(c, lnum, snod->offs, snod->len,
620 &snod->key, snod->sqnum, deletion,
621 &used, 0, new_size);
622 break;
623 }
624 case UBIFS_DENT_NODE:
625 case UBIFS_XENT_NODE:
626 {
627 struct ubifs_dent_node *dent = snod->node;
628
629 err = ubifs_validate_entry(c, dent);
630 if (err)
631 goto out_dump;
632
633 err = insert_dent(c, lnum, snod->offs, snod->len,
634 &snod->key, dent->name,
635 le16_to_cpu(dent->nlen), snod->sqnum,
636 !le64_to_cpu(dent->inum), &used);
637 break;
638 }
639 case UBIFS_TRUN_NODE:
640 {
641 struct ubifs_trun_node *trun = snod->node;
642 loff_t old_size = le64_to_cpu(trun->old_size);
643 loff_t new_size = le64_to_cpu(trun->new_size);
644 union ubifs_key key;
645
646 /* Validate truncation node */
647 if (old_size < 0 || old_size > c->max_inode_sz ||
648 new_size < 0 || new_size > c->max_inode_sz ||
649 old_size <= new_size) {
650 ubifs_err("bad truncation node");
651 goto out_dump;
652 }
653
654 /*
655 * Create a fake truncation key just to use the same
656 * functions which expect nodes to have keys.
657 */
658 trun_key_init(c, &key, le32_to_cpu(trun->inum));
659 err = insert_node(c, lnum, snod->offs, snod->len,
660 &key, snod->sqnum, 1, &used,
661 old_size, new_size);
662 break;
663 }
664 default:
665 ubifs_err("unexpected node type %d in bud LEB %d:%d",
666 snod->type, lnum, snod->offs);
667 err = -EINVAL;
668 goto out_dump;
669 }
670 if (err)
671 goto out;
672 }
673
674 ubifs_assert(ubifs_search_bud(c, lnum));
675 ubifs_assert(sleb->endpt - offs >= used);
676 ubifs_assert(sleb->endpt % c->min_io_size == 0);
677
678 b->dirty = sleb->endpt - offs - used;
679 b->free = c->leb_size - sleb->endpt;
680 dbg_mnt("bud LEB %d replied: dirty %d, free %d", lnum, b->dirty, b->free);
681
682out:
683 ubifs_scan_destroy(sleb);
684 return err;
685
686out_dump:
687 ubifs_err("bad node is at LEB %d:%d", lnum, snod->offs);
688 ubifs_dump_node(c, snod->node);
689 ubifs_scan_destroy(sleb);
690 return -EINVAL;
691}
692
693/**
694 * replay_buds - replay all buds.
695 * @c: UBIFS file-system description object
696 *
697 * This function returns zero in case of success and a negative error code in
698 * case of failure.
699 */
700static int replay_buds(struct ubifs_info *c)
701{
702 struct bud_entry *b;
703 int err;
704 unsigned long long prev_sqnum = 0;
705
706 list_for_each_entry(b, &c->replay_buds, list) {
707 err = replay_bud(c, b);
708 if (err)
709 return err;
710
711 ubifs_assert(b->sqnum > prev_sqnum);
712 prev_sqnum = b->sqnum;
713 }
714
715 return 0;
716}
717
718/**
719 * destroy_bud_list - destroy the list of buds to replay.
720 * @c: UBIFS file-system description object
721 */
722static void destroy_bud_list(struct ubifs_info *c)
723{
724 struct bud_entry *b;
725
726 while (!list_empty(&c->replay_buds)) {
727 b = list_entry(c->replay_buds.next, struct bud_entry, list);
728 list_del(&b->list);
729 kfree(b);
730 }
731}
732
733/**
734 * add_replay_bud - add a bud to the list of buds to replay.
735 * @c: UBIFS file-system description object
736 * @lnum: bud logical eraseblock number to replay
737 * @offs: bud start offset
738 * @jhead: journal head to which this bud belongs
739 * @sqnum: reference node sequence number
740 *
741 * This function returns zero in case of success and a negative error code in
742 * case of failure.
743 */
744static int add_replay_bud(struct ubifs_info *c, int lnum, int offs, int jhead,
745 unsigned long long sqnum)
746{
747 struct ubifs_bud *bud;
748 struct bud_entry *b;
749
750 dbg_mnt("add replay bud LEB %d:%d, head %d", lnum, offs, jhead);
751
752 bud = kmalloc(sizeof(struct ubifs_bud), GFP_KERNEL);
753 if (!bud)
754 return -ENOMEM;
755
756 b = kmalloc(sizeof(struct bud_entry), GFP_KERNEL);
757 if (!b) {
758 kfree(bud);
759 return -ENOMEM;
760 }
761
762 bud->lnum = lnum;
763 bud->start = offs;
764 bud->jhead = jhead;
765 ubifs_add_bud(c, bud);
766
767 b->bud = bud;
768 b->sqnum = sqnum;
769 list_add_tail(&b->list, &c->replay_buds);
770
771 return 0;
772}
773
774/**
775 * validate_ref - validate a reference node.
776 * @c: UBIFS file-system description object
777 * @ref: the reference node to validate
778 * @ref_lnum: LEB number of the reference node
779 * @ref_offs: reference node offset
780 *
781 * This function returns %1 if a bud reference already exists for the LEB. %0 is
782 * returned if the reference node is new, otherwise %-EINVAL is returned if
783 * validation failed.
784 */
785static int validate_ref(struct ubifs_info *c, const struct ubifs_ref_node *ref)
786{
787 struct ubifs_bud *bud;
788 int lnum = le32_to_cpu(ref->lnum);
789 unsigned int offs = le32_to_cpu(ref->offs);
790 unsigned int jhead = le32_to_cpu(ref->jhead);
791
792 /*
793 * ref->offs may point to the end of LEB when the journal head points
794 * to the end of LEB and we write reference node for it during commit.
795 * So this is why we require 'offs > c->leb_size'.
796 */
797 if (jhead >= c->jhead_cnt || lnum >= c->leb_cnt ||
798 lnum < c->main_first || offs > c->leb_size ||
799 offs & (c->min_io_size - 1))
800 return -EINVAL;
801
802 /* Make sure we have not already looked at this bud */
803 bud = ubifs_search_bud(c, lnum);
804 if (bud) {
805 if (bud->jhead == jhead && bud->start <= offs)
806 return 1;
807 ubifs_err("bud at LEB %d:%d was already referred", lnum, offs);
808 return -EINVAL;
809 }
810
811 return 0;
812}
813
814/**
815 * replay_log_leb - replay a log logical eraseblock.
816 * @c: UBIFS file-system description object
817 * @lnum: log logical eraseblock to replay
818 * @offs: offset to start replaying from
819 * @sbuf: scan buffer
820 *
821 * This function replays a log LEB and returns zero in case of success, %1 if
822 * this is the last LEB in the log, and a negative error code in case of
823 * failure.
824 */
825static int replay_log_leb(struct ubifs_info *c, int lnum, int offs, void *sbuf)
826{
827 int err;
828 struct ubifs_scan_leb *sleb;
829 struct ubifs_scan_node *snod;
830 const struct ubifs_cs_node *node;
831
832 dbg_mnt("replay log LEB %d:%d", lnum, offs);
833 sleb = ubifs_scan(c, lnum, offs, sbuf, c->need_recovery);
834 if (IS_ERR(sleb)) {
835 if (PTR_ERR(sleb) != -EUCLEAN || !c->need_recovery)
836 return PTR_ERR(sleb);
837 /*
838 * Note, the below function will recover this log LEB only if
839 * it is the last, because unclean reboots can possibly corrupt
840 * only the tail of the log.
841 */
842 sleb = ubifs_recover_log_leb(c, lnum, offs, sbuf);
843 if (IS_ERR(sleb))
844 return PTR_ERR(sleb);
845 }
846
847 if (sleb->nodes_cnt == 0) {
848 err = 1;
849 goto out;
850 }
851
852 node = sleb->buf;
853 snod = list_entry(sleb->nodes.next, struct ubifs_scan_node, list);
854 if (c->cs_sqnum == 0) {
855 /*
856 * This is the first log LEB we are looking at, make sure that
857 * the first node is a commit start node. Also record its
858 * sequence number so that UBIFS can determine where the log
859 * ends, because all nodes which were have higher sequence
860 * numbers.
861 */
862 if (snod->type != UBIFS_CS_NODE) {
863 ubifs_err("first log node at LEB %d:%d is not CS node",
864 lnum, offs);
865 goto out_dump;
866 }
867 if (le64_to_cpu(node->cmt_no) != c->cmt_no) {
868 ubifs_err("first CS node at LEB %d:%d has wrong "
869 "commit number %llu expected %llu",
870 lnum, offs,
871 (unsigned long long)le64_to_cpu(node->cmt_no),
872 c->cmt_no);
873 goto out_dump;
874 }
875
876 c->cs_sqnum = le64_to_cpu(node->ch.sqnum);
877 dbg_mnt("commit start sqnum %llu", c->cs_sqnum);
878 }
879
880 if (snod->sqnum < c->cs_sqnum) {
881 /*
882 * This means that we reached end of log and now
883 * look to the older log data, which was already
884 * committed but the eraseblock was not erased (UBIFS
885 * only un-maps it). So this basically means we have to
886 * exit with "end of log" code.
887 */
888 err = 1;
889 goto out;
890 }
891
892 /* Make sure the first node sits at offset zero of the LEB */
893 if (snod->offs != 0) {
894 ubifs_err("first node is not at zero offset");
895 goto out_dump;
896 }
897
898 list_for_each_entry(snod, &sleb->nodes, list) {
899 cond_resched();
900
901 if (snod->sqnum >= SQNUM_WATERMARK) {
902 ubifs_err("file system's life ended");
903 goto out_dump;
904 }
905
906 if (snod->sqnum < c->cs_sqnum) {
907 ubifs_err("bad sqnum %llu, commit sqnum %llu",
908 snod->sqnum, c->cs_sqnum);
909 goto out_dump;
910 }
911
912 if (snod->sqnum > c->max_sqnum)
913 c->max_sqnum = snod->sqnum;
914
915 switch (snod->type) {
916 case UBIFS_REF_NODE: {
917 const struct ubifs_ref_node *ref = snod->node;
918
919 err = validate_ref(c, ref);
920 if (err == 1)
921 break; /* Already have this bud */
922 if (err)
923 goto out_dump;
924
925 err = add_replay_bud(c, le32_to_cpu(ref->lnum),
926 le32_to_cpu(ref->offs),
927 le32_to_cpu(ref->jhead),
928 snod->sqnum);
929 if (err)
930 goto out;
931
932 break;
933 }
934 case UBIFS_CS_NODE:
935 /* Make sure it sits at the beginning of LEB */
936 if (snod->offs != 0) {
937 ubifs_err("unexpected node in log");
938 goto out_dump;
939 }
940 break;
941 default:
942 ubifs_err("unexpected node in log");
943 goto out_dump;
944 }
945 }
946
947 if (sleb->endpt || c->lhead_offs >= c->leb_size) {
948 c->lhead_lnum = lnum;
949 c->lhead_offs = sleb->endpt;
950 }
951
952 err = !sleb->endpt;
953out:
954 ubifs_scan_destroy(sleb);
955 return err;
956
957out_dump:
958 ubifs_err("log error detected while replaying the log at LEB %d:%d",
959 lnum, offs + snod->offs);
960 ubifs_dump_node(c, snod->node);
961 ubifs_scan_destroy(sleb);
962 return -EINVAL;
963}
964
965/**
966 * take_ihead - update the status of the index head in lprops to 'taken'.
967 * @c: UBIFS file-system description object
968 *
969 * This function returns the amount of free space in the index head LEB or a
970 * negative error code.
971 */
972static int take_ihead(struct ubifs_info *c)
973{
974 const struct ubifs_lprops *lp;
975 int err, free;
976
977 ubifs_get_lprops(c);
978
979 lp = ubifs_lpt_lookup_dirty(c, c->ihead_lnum);
980 if (IS_ERR(lp)) {
981 err = PTR_ERR(lp);
982 goto out;
983 }
984
985 free = lp->free;
986
987 lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC,
988 lp->flags | LPROPS_TAKEN, 0);
989 if (IS_ERR(lp)) {
990 err = PTR_ERR(lp);
991 goto out;
992 }
993
994 err = free;
995out:
996 ubifs_release_lprops(c);
997 return err;
998}
999
1000/**
1001 * ubifs_replay_journal - replay journal.
1002 * @c: UBIFS file-system description object
1003 *
1004 * This function scans the journal, replays and cleans it up. It makes sure all
1005 * memory data structures related to uncommitted journal are built (dirty TNC
1006 * tree, tree of buds, modified lprops, etc).
1007 */
1008int ubifs_replay_journal(struct ubifs_info *c)
1009{
1010 int err, i, lnum, offs, free;
1011
1012 BUILD_BUG_ON(UBIFS_TRUN_KEY > 5);
1013
1014 /* Update the status of the index head in lprops to 'taken' */
1015 free = take_ihead(c);
1016 if (free < 0)
1017 return free; /* Error code */
1018
1019 if (c->ihead_offs != c->leb_size - free) {
1020 ubifs_err("bad index head LEB %d:%d", c->ihead_lnum,
1021 c->ihead_offs);
1022 return -EINVAL;
1023 }
1024
1025 dbg_mnt("start replaying the journal");
1026 c->replaying = 1;
1027 lnum = c->ltail_lnum = c->lhead_lnum;
1028 offs = c->lhead_offs;
1029
1030 for (i = 0; i < c->log_lebs; i++, lnum++) {
1031 if (lnum >= UBIFS_LOG_LNUM + c->log_lebs) {
1032 /*
1033 * The log is logically circular, we reached the last
1034 * LEB, switch to the first one.
1035 */
1036 lnum = UBIFS_LOG_LNUM;
1037 offs = 0;
1038 }
1039 err = replay_log_leb(c, lnum, offs, c->sbuf);
1040 if (err == 1)
1041 /* We hit the end of the log */
1042 break;
1043 if (err)
1044 goto out;
1045 offs = 0;
1046 }
1047
1048 err = replay_buds(c);
1049 if (err)
1050 goto out;
1051
1052 err = apply_replay_list(c);
1053 if (err)
1054 goto out;
1055
1056 err = set_buds_lprops(c);
1057 if (err)
1058 goto out;
1059
1060 /*
1061 * UBIFS budgeting calculations use @c->bi.uncommitted_idx variable
1062 * to roughly estimate index growth. Things like @c->bi.min_idx_lebs
1063 * depend on it. This means we have to initialize it to make sure
1064 * budgeting works properly.
1065 */
1066 c->bi.uncommitted_idx = atomic_long_read(&c->dirty_zn_cnt);
1067 c->bi.uncommitted_idx *= c->max_idx_node_sz;
1068
1069 ubifs_assert(c->bud_bytes <= c->max_bud_bytes || c->need_recovery);
1070 dbg_mnt("finished, log head LEB %d:%d, max_sqnum %llu, "
1071 "highest_inum %lu", c->lhead_lnum, c->lhead_offs, c->max_sqnum,
1072 (unsigned long)c->highest_inum);
1073out:
1074 destroy_replay_list(c);
1075 destroy_bud_list(c);
1076 c->replaying = 0;
1077 return err;
1078}