aboutsummaryrefslogtreecommitdiffstats
path: root/fs/ubifs/recovery.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/ubifs/recovery.c')
-rw-r--r--fs/ubifs/recovery.c1519
1 files changed, 1519 insertions, 0 deletions
diff --git a/fs/ubifs/recovery.c b/fs/ubifs/recovery.c
new file mode 100644
index 000000000000..77d26c141cf6
--- /dev/null
+++ b/fs/ubifs/recovery.c
@@ -0,0 +1,1519 @@
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 implements functions needed to recover from unclean un-mounts.
25 * When UBIFS is mounted, it checks a flag on the master node to determine if
26 * an un-mount was completed sucessfully. If not, the process of mounting
27 * incorparates additional checking and fixing of on-flash data structures.
28 * UBIFS always cleans away all remnants of an unclean un-mount, so that
29 * errors do not accumulate. However UBIFS defers recovery if it is mounted
30 * read-only, and the flash is not modified in that case.
31 */
32
33#include <linux/crc32.h>
34#include "ubifs.h"
35
36/**
37 * is_empty - determine whether a buffer is empty (contains all 0xff).
38 * @buf: buffer to clean
39 * @len: length of buffer
40 *
41 * This function returns %1 if the buffer is empty (contains all 0xff) otherwise
42 * %0 is returned.
43 */
44static int is_empty(void *buf, int len)
45{
46 uint8_t *p = buf;
47 int i;
48
49 for (i = 0; i < len; i++)
50 if (*p++ != 0xff)
51 return 0;
52 return 1;
53}
54
55/**
56 * get_master_node - get the last valid master node allowing for corruption.
57 * @c: UBIFS file-system description object
58 * @lnum: LEB number
59 * @pbuf: buffer containing the LEB read, is returned here
60 * @mst: master node, if found, is returned here
61 * @cor: corruption, if found, is returned here
62 *
63 * This function allocates a buffer, reads the LEB into it, and finds and
64 * returns the last valid master node allowing for one area of corruption.
65 * The corrupt area, if there is one, must be consistent with the assumption
66 * that it is the result of an unclean unmount while the master node was being
67 * written. Under those circumstances, it is valid to use the previously written
68 * master node.
69 *
70 * This function returns %0 on success and a negative error code on failure.
71 */
72static int get_master_node(const struct ubifs_info *c, int lnum, void **pbuf,
73 struct ubifs_mst_node **mst, void **cor)
74{
75 const int sz = c->mst_node_alsz;
76 int err, offs, len;
77 void *sbuf, *buf;
78
79 sbuf = vmalloc(c->leb_size);
80 if (!sbuf)
81 return -ENOMEM;
82
83 err = ubi_read(c->ubi, lnum, sbuf, 0, c->leb_size);
84 if (err && err != -EBADMSG)
85 goto out_free;
86
87 /* Find the first position that is definitely not a node */
88 offs = 0;
89 buf = sbuf;
90 len = c->leb_size;
91 while (offs + UBIFS_MST_NODE_SZ <= c->leb_size) {
92 struct ubifs_ch *ch = buf;
93
94 if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC)
95 break;
96 offs += sz;
97 buf += sz;
98 len -= sz;
99 }
100 /* See if there was a valid master node before that */
101 if (offs) {
102 int ret;
103
104 offs -= sz;
105 buf -= sz;
106 len += sz;
107 ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
108 if (ret != SCANNED_A_NODE && offs) {
109 /* Could have been corruption so check one place back */
110 offs -= sz;
111 buf -= sz;
112 len += sz;
113 ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
114 if (ret != SCANNED_A_NODE)
115 /*
116 * We accept only one area of corruption because
117 * we are assuming that it was caused while
118 * trying to write a master node.
119 */
120 goto out_err;
121 }
122 if (ret == SCANNED_A_NODE) {
123 struct ubifs_ch *ch = buf;
124
125 if (ch->node_type != UBIFS_MST_NODE)
126 goto out_err;
127 dbg_rcvry("found a master node at %d:%d", lnum, offs);
128 *mst = buf;
129 offs += sz;
130 buf += sz;
131 len -= sz;
132 }
133 }
134 /* Check for corruption */
135 if (offs < c->leb_size) {
136 if (!is_empty(buf, min_t(int, len, sz))) {
137 *cor = buf;
138 dbg_rcvry("found corruption at %d:%d", lnum, offs);
139 }
140 offs += sz;
141 buf += sz;
142 len -= sz;
143 }
144 /* Check remaining empty space */
145 if (offs < c->leb_size)
146 if (!is_empty(buf, len))
147 goto out_err;
148 *pbuf = sbuf;
149 return 0;
150
151out_err:
152 err = -EINVAL;
153out_free:
154 vfree(sbuf);
155 *mst = NULL;
156 *cor = NULL;
157 return err;
158}
159
160/**
161 * write_rcvrd_mst_node - write recovered master node.
162 * @c: UBIFS file-system description object
163 * @mst: master node
164 *
165 * This function returns %0 on success and a negative error code on failure.
166 */
167static int write_rcvrd_mst_node(struct ubifs_info *c,
168 struct ubifs_mst_node *mst)
169{
170 int err = 0, lnum = UBIFS_MST_LNUM, sz = c->mst_node_alsz;
171 uint32_t save_flags;
172
173 dbg_rcvry("recovery");
174
175 save_flags = mst->flags;
176 mst->flags = cpu_to_le32(le32_to_cpu(mst->flags) | UBIFS_MST_RCVRY);
177
178 ubifs_prepare_node(c, mst, UBIFS_MST_NODE_SZ, 1);
179 err = ubi_leb_change(c->ubi, lnum, mst, sz, UBI_SHORTTERM);
180 if (err)
181 goto out;
182 err = ubi_leb_change(c->ubi, lnum + 1, mst, sz, UBI_SHORTTERM);
183 if (err)
184 goto out;
185out:
186 mst->flags = save_flags;
187 return err;
188}
189
190/**
191 * ubifs_recover_master_node - recover the master node.
192 * @c: UBIFS file-system description object
193 *
194 * This function recovers the master node from corruption that may occur due to
195 * an unclean unmount.
196 *
197 * This function returns %0 on success and a negative error code on failure.
198 */
199int ubifs_recover_master_node(struct ubifs_info *c)
200{
201 void *buf1 = NULL, *buf2 = NULL, *cor1 = NULL, *cor2 = NULL;
202 struct ubifs_mst_node *mst1 = NULL, *mst2 = NULL, *mst;
203 const int sz = c->mst_node_alsz;
204 int err, offs1, offs2;
205
206 dbg_rcvry("recovery");
207
208 err = get_master_node(c, UBIFS_MST_LNUM, &buf1, &mst1, &cor1);
209 if (err)
210 goto out_free;
211
212 err = get_master_node(c, UBIFS_MST_LNUM + 1, &buf2, &mst2, &cor2);
213 if (err)
214 goto out_free;
215
216 if (mst1) {
217 offs1 = (void *)mst1 - buf1;
218 if ((le32_to_cpu(mst1->flags) & UBIFS_MST_RCVRY) &&
219 (offs1 == 0 && !cor1)) {
220 /*
221 * mst1 was written by recovery at offset 0 with no
222 * corruption.
223 */
224 dbg_rcvry("recovery recovery");
225 mst = mst1;
226 } else if (mst2) {
227 offs2 = (void *)mst2 - buf2;
228 if (offs1 == offs2) {
229 /* Same offset, so must be the same */
230 if (memcmp((void *)mst1 + UBIFS_CH_SZ,
231 (void *)mst2 + UBIFS_CH_SZ,
232 UBIFS_MST_NODE_SZ - UBIFS_CH_SZ))
233 goto out_err;
234 mst = mst1;
235 } else if (offs2 + sz == offs1) {
236 /* 1st LEB was written, 2nd was not */
237 if (cor1)
238 goto out_err;
239 mst = mst1;
240 } else if (offs1 == 0 && offs2 + sz >= c->leb_size) {
241 /* 1st LEB was unmapped and written, 2nd not */
242 if (cor1)
243 goto out_err;
244 mst = mst1;
245 } else
246 goto out_err;
247 } else {
248 /*
249 * 2nd LEB was unmapped and about to be written, so
250 * there must be only one master node in the first LEB
251 * and no corruption.
252 */
253 if (offs1 != 0 || cor1)
254 goto out_err;
255 mst = mst1;
256 }
257 } else {
258 if (!mst2)
259 goto out_err;
260 /*
261 * 1st LEB was unmapped and about to be written, so there must
262 * be no room left in 2nd LEB.
263 */
264 offs2 = (void *)mst2 - buf2;
265 if (offs2 + sz + sz <= c->leb_size)
266 goto out_err;
267 mst = mst2;
268 }
269
270 dbg_rcvry("recovered master node from LEB %d",
271 (mst == mst1 ? UBIFS_MST_LNUM : UBIFS_MST_LNUM + 1));
272
273 memcpy(c->mst_node, mst, UBIFS_MST_NODE_SZ);
274
275 if ((c->vfs_sb->s_flags & MS_RDONLY)) {
276 /* Read-only mode. Keep a copy for switching to rw mode */
277 c->rcvrd_mst_node = kmalloc(sz, GFP_KERNEL);
278 if (!c->rcvrd_mst_node) {
279 err = -ENOMEM;
280 goto out_free;
281 }
282 memcpy(c->rcvrd_mst_node, c->mst_node, UBIFS_MST_NODE_SZ);
283 } else {
284 /* Write the recovered master node */
285 c->max_sqnum = le64_to_cpu(mst->ch.sqnum) - 1;
286 err = write_rcvrd_mst_node(c, c->mst_node);
287 if (err)
288 goto out_free;
289 }
290
291 vfree(buf2);
292 vfree(buf1);
293
294 return 0;
295
296out_err:
297 err = -EINVAL;
298out_free:
299 ubifs_err("failed to recover master node");
300 if (mst1) {
301 dbg_err("dumping first master node");
302 dbg_dump_node(c, mst1);
303 }
304 if (mst2) {
305 dbg_err("dumping second master node");
306 dbg_dump_node(c, mst2);
307 }
308 vfree(buf2);
309 vfree(buf1);
310 return err;
311}
312
313/**
314 * ubifs_write_rcvrd_mst_node - write the recovered master node.
315 * @c: UBIFS file-system description object
316 *
317 * This function writes the master node that was recovered during mounting in
318 * read-only mode and must now be written because we are remounting rw.
319 *
320 * This function returns %0 on success and a negative error code on failure.
321 */
322int ubifs_write_rcvrd_mst_node(struct ubifs_info *c)
323{
324 int err;
325
326 if (!c->rcvrd_mst_node)
327 return 0;
328 c->rcvrd_mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
329 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
330 err = write_rcvrd_mst_node(c, c->rcvrd_mst_node);
331 if (err)
332 return err;
333 kfree(c->rcvrd_mst_node);
334 c->rcvrd_mst_node = NULL;
335 return 0;
336}
337
338/**
339 * is_last_write - determine if an offset was in the last write to a LEB.
340 * @c: UBIFS file-system description object
341 * @buf: buffer to check
342 * @offs: offset to check
343 *
344 * This function returns %1 if @offs was in the last write to the LEB whose data
345 * is in @buf, otherwise %0 is returned. The determination is made by checking
346 * for subsequent empty space starting from the next min_io_size boundary (or a
347 * bit less than the common header size if min_io_size is one).
348 */
349static int is_last_write(const struct ubifs_info *c, void *buf, int offs)
350{
351 int empty_offs;
352 int check_len;
353 uint8_t *p;
354
355 if (c->min_io_size == 1) {
356 check_len = c->leb_size - offs;
357 p = buf + check_len;
358 for (; check_len > 0; check_len--)
359 if (*--p != 0xff)
360 break;
361 /*
362 * 'check_len' is the size of the corruption which cannot be
363 * more than the size of 1 node if it was caused by an unclean
364 * unmount.
365 */
366 if (check_len > UBIFS_MAX_NODE_SZ)
367 return 0;
368 return 1;
369 }
370
371 /*
372 * Round up to the next c->min_io_size boundary i.e. 'offs' is in the
373 * last wbuf written. After that should be empty space.
374 */
375 empty_offs = ALIGN(offs + 1, c->min_io_size);
376 check_len = c->leb_size - empty_offs;
377 p = buf + empty_offs - offs;
378
379 for (; check_len > 0; check_len--)
380 if (*p++ != 0xff)
381 return 0;
382 return 1;
383}
384
385/**
386 * clean_buf - clean the data from an LEB sitting in a buffer.
387 * @c: UBIFS file-system description object
388 * @buf: buffer to clean
389 * @lnum: LEB number to clean
390 * @offs: offset from which to clean
391 * @len: length of buffer
392 *
393 * This function pads up to the next min_io_size boundary (if there is one) and
394 * sets empty space to all 0xff. @buf, @offs and @len are updated to the next
395 * min_io_size boundary (if there is one).
396 */
397static void clean_buf(const struct ubifs_info *c, void **buf, int lnum,
398 int *offs, int *len)
399{
400 int empty_offs, pad_len;
401
402 lnum = lnum;
403 dbg_rcvry("cleaning corruption at %d:%d", lnum, *offs);
404
405 if (c->min_io_size == 1) {
406 memset(*buf, 0xff, c->leb_size - *offs);
407 return;
408 }
409
410 ubifs_assert(!(*offs & 7));
411 empty_offs = ALIGN(*offs, c->min_io_size);
412 pad_len = empty_offs - *offs;
413 ubifs_pad(c, *buf, pad_len);
414 *offs += pad_len;
415 *buf += pad_len;
416 *len -= pad_len;
417 memset(*buf, 0xff, c->leb_size - empty_offs);
418}
419
420/**
421 * no_more_nodes - determine if there are no more nodes in a buffer.
422 * @c: UBIFS file-system description object
423 * @buf: buffer to check
424 * @len: length of buffer
425 * @lnum: LEB number of the LEB from which @buf was read
426 * @offs: offset from which @buf was read
427 *
428 * This function scans @buf for more nodes and returns %0 is a node is found and
429 * %1 if no more nodes are found.
430 */
431static int no_more_nodes(const struct ubifs_info *c, void *buf, int len,
432 int lnum, int offs)
433{
434 int skip, next_offs = 0;
435
436 if (len > UBIFS_DATA_NODE_SZ) {
437 struct ubifs_ch *ch = buf;
438 int dlen = le32_to_cpu(ch->len);
439
440 if (ch->node_type == UBIFS_DATA_NODE && dlen >= UBIFS_CH_SZ &&
441 dlen <= UBIFS_MAX_DATA_NODE_SZ)
442 /* The corrupt node looks like a data node */
443 next_offs = ALIGN(offs + dlen, 8);
444 }
445
446 if (c->min_io_size == 1)
447 skip = 8;
448 else
449 skip = ALIGN(offs + 1, c->min_io_size) - offs;
450
451 offs += skip;
452 buf += skip;
453 len -= skip;
454 while (len > 8) {
455 struct ubifs_ch *ch = buf;
456 uint32_t magic = le32_to_cpu(ch->magic);
457 int ret;
458
459 if (magic == UBIFS_NODE_MAGIC) {
460 ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
461 if (ret == SCANNED_A_NODE || ret > 0) {
462 /*
463 * There is a small chance this is just data in
464 * a data node, so check that possibility. e.g.
465 * this is part of a file that itself contains
466 * a UBIFS image.
467 */
468 if (next_offs && offs + le32_to_cpu(ch->len) <=
469 next_offs)
470 continue;
471 dbg_rcvry("unexpected node at %d:%d", lnum,
472 offs);
473 return 0;
474 }
475 }
476 offs += 8;
477 buf += 8;
478 len -= 8;
479 }
480 return 1;
481}
482
483/**
484 * fix_unclean_leb - fix an unclean LEB.
485 * @c: UBIFS file-system description object
486 * @sleb: scanned LEB information
487 * @start: offset where scan started
488 */
489static int fix_unclean_leb(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
490 int start)
491{
492 int lnum = sleb->lnum, endpt = start;
493
494 /* Get the end offset of the last node we are keeping */
495 if (!list_empty(&sleb->nodes)) {
496 struct ubifs_scan_node *snod;
497
498 snod = list_entry(sleb->nodes.prev,
499 struct ubifs_scan_node, list);
500 endpt = snod->offs + snod->len;
501 }
502
503 if ((c->vfs_sb->s_flags & MS_RDONLY) && !c->remounting_rw) {
504 /* Add to recovery list */
505 struct ubifs_unclean_leb *ucleb;
506
507 dbg_rcvry("need to fix LEB %d start %d endpt %d",
508 lnum, start, sleb->endpt);
509 ucleb = kzalloc(sizeof(struct ubifs_unclean_leb), GFP_NOFS);
510 if (!ucleb)
511 return -ENOMEM;
512 ucleb->lnum = lnum;
513 ucleb->endpt = endpt;
514 list_add_tail(&ucleb->list, &c->unclean_leb_list);
515 } else {
516 /* Write the fixed LEB back to flash */
517 int err;
518
519 dbg_rcvry("fixing LEB %d start %d endpt %d",
520 lnum, start, sleb->endpt);
521 if (endpt == 0) {
522 err = ubifs_leb_unmap(c, lnum);
523 if (err)
524 return err;
525 } else {
526 int len = ALIGN(endpt, c->min_io_size);
527
528 if (start) {
529 err = ubi_read(c->ubi, lnum, sleb->buf, 0,
530 start);
531 if (err)
532 return err;
533 }
534 /* Pad to min_io_size */
535 if (len > endpt) {
536 int pad_len = len - ALIGN(endpt, 8);
537
538 if (pad_len > 0) {
539 void *buf = sleb->buf + len - pad_len;
540
541 ubifs_pad(c, buf, pad_len);
542 }
543 }
544 err = ubi_leb_change(c->ubi, lnum, sleb->buf, len,
545 UBI_UNKNOWN);
546 if (err)
547 return err;
548 }
549 }
550 return 0;
551}
552
553/**
554 * drop_incomplete_group - drop nodes from an incomplete group.
555 * @sleb: scanned LEB information
556 * @offs: offset of dropped nodes is returned here
557 *
558 * This function returns %1 if nodes are dropped and %0 otherwise.
559 */
560static int drop_incomplete_group(struct ubifs_scan_leb *sleb, int *offs)
561{
562 int dropped = 0;
563
564 while (!list_empty(&sleb->nodes)) {
565 struct ubifs_scan_node *snod;
566 struct ubifs_ch *ch;
567
568 snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node,
569 list);
570 ch = snod->node;
571 if (ch->group_type != UBIFS_IN_NODE_GROUP)
572 return dropped;
573 dbg_rcvry("dropping node at %d:%d", sleb->lnum, snod->offs);
574 *offs = snod->offs;
575 list_del(&snod->list);
576 kfree(snod);
577 sleb->nodes_cnt -= 1;
578 dropped = 1;
579 }
580 return dropped;
581}
582
583/**
584 * ubifs_recover_leb - scan and recover a LEB.
585 * @c: UBIFS file-system description object
586 * @lnum: LEB number
587 * @offs: offset
588 * @sbuf: LEB-sized buffer to use
589 * @grouped: nodes may be grouped for recovery
590 *
591 * This function does a scan of a LEB, but caters for errors that might have
592 * been caused by the unclean unmount from which we are attempting to recover.
593 *
594 * This function returns %0 on success and a negative error code on failure.
595 */
596struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
597 int offs, void *sbuf, int grouped)
598{
599 int err, len = c->leb_size - offs, need_clean = 0, quiet = 1;
600 int empty_chkd = 0, start = offs;
601 struct ubifs_scan_leb *sleb;
602 void *buf = sbuf + offs;
603
604 dbg_rcvry("%d:%d", lnum, offs);
605
606 sleb = ubifs_start_scan(c, lnum, offs, sbuf);
607 if (IS_ERR(sleb))
608 return sleb;
609
610 if (sleb->ecc)
611 need_clean = 1;
612
613 while (len >= 8) {
614 int ret;
615
616 dbg_scan("look at LEB %d:%d (%d bytes left)",
617 lnum, offs, len);
618
619 cond_resched();
620
621 /*
622 * Scan quietly until there is an error from which we cannot
623 * recover
624 */
625 ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet);
626
627 if (ret == SCANNED_A_NODE) {
628 /* A valid node, and not a padding node */
629 struct ubifs_ch *ch = buf;
630 int node_len;
631
632 err = ubifs_add_snod(c, sleb, buf, offs);
633 if (err)
634 goto error;
635 node_len = ALIGN(le32_to_cpu(ch->len), 8);
636 offs += node_len;
637 buf += node_len;
638 len -= node_len;
639 continue;
640 }
641
642 if (ret > 0) {
643 /* Padding bytes or a valid padding node */
644 offs += ret;
645 buf += ret;
646 len -= ret;
647 continue;
648 }
649
650 if (ret == SCANNED_EMPTY_SPACE) {
651 if (!is_empty(buf, len)) {
652 if (!is_last_write(c, buf, offs))
653 break;
654 clean_buf(c, &buf, lnum, &offs, &len);
655 need_clean = 1;
656 }
657 empty_chkd = 1;
658 break;
659 }
660
661 if (ret == SCANNED_GARBAGE || ret == SCANNED_A_BAD_PAD_NODE)
662 if (is_last_write(c, buf, offs)) {
663 clean_buf(c, &buf, lnum, &offs, &len);
664 need_clean = 1;
665 empty_chkd = 1;
666 break;
667 }
668
669 if (ret == SCANNED_A_CORRUPT_NODE)
670 if (no_more_nodes(c, buf, len, lnum, offs)) {
671 clean_buf(c, &buf, lnum, &offs, &len);
672 need_clean = 1;
673 empty_chkd = 1;
674 break;
675 }
676
677 if (quiet) {
678 /* Redo the last scan but noisily */
679 quiet = 0;
680 continue;
681 }
682
683 switch (ret) {
684 case SCANNED_GARBAGE:
685 dbg_err("garbage");
686 goto corrupted;
687 case SCANNED_A_CORRUPT_NODE:
688 case SCANNED_A_BAD_PAD_NODE:
689 dbg_err("bad node");
690 goto corrupted;
691 default:
692 dbg_err("unknown");
693 goto corrupted;
694 }
695 }
696
697 if (!empty_chkd && !is_empty(buf, len)) {
698 if (is_last_write(c, buf, offs)) {
699 clean_buf(c, &buf, lnum, &offs, &len);
700 need_clean = 1;
701 } else {
702 ubifs_err("corrupt empty space at LEB %d:%d",
703 lnum, offs);
704 goto corrupted;
705 }
706 }
707
708 /* Drop nodes from incomplete group */
709 if (grouped && drop_incomplete_group(sleb, &offs)) {
710 buf = sbuf + offs;
711 len = c->leb_size - offs;
712 clean_buf(c, &buf, lnum, &offs, &len);
713 need_clean = 1;
714 }
715
716 if (offs % c->min_io_size) {
717 clean_buf(c, &buf, lnum, &offs, &len);
718 need_clean = 1;
719 }
720
721 ubifs_end_scan(c, sleb, lnum, offs);
722
723 if (need_clean) {
724 err = fix_unclean_leb(c, sleb, start);
725 if (err)
726 goto error;
727 }
728
729 return sleb;
730
731corrupted:
732 ubifs_scanned_corruption(c, lnum, offs, buf);
733 err = -EUCLEAN;
734error:
735 ubifs_err("LEB %d scanning failed", lnum);
736 ubifs_scan_destroy(sleb);
737 return ERR_PTR(err);
738}
739
740/**
741 * get_cs_sqnum - get commit start sequence number.
742 * @c: UBIFS file-system description object
743 * @lnum: LEB number of commit start node
744 * @offs: offset of commit start node
745 * @cs_sqnum: commit start sequence number is returned here
746 *
747 * This function returns %0 on success and a negative error code on failure.
748 */
749static int get_cs_sqnum(struct ubifs_info *c, int lnum, int offs,
750 unsigned long long *cs_sqnum)
751{
752 struct ubifs_cs_node *cs_node = NULL;
753 int err, ret;
754
755 dbg_rcvry("at %d:%d", lnum, offs);
756 cs_node = kmalloc(UBIFS_CS_NODE_SZ, GFP_KERNEL);
757 if (!cs_node)
758 return -ENOMEM;
759 if (c->leb_size - offs < UBIFS_CS_NODE_SZ)
760 goto out_err;
761 err = ubi_read(c->ubi, lnum, (void *)cs_node, offs, UBIFS_CS_NODE_SZ);
762 if (err && err != -EBADMSG)
763 goto out_free;
764 ret = ubifs_scan_a_node(c, cs_node, UBIFS_CS_NODE_SZ, lnum, offs, 0);
765 if (ret != SCANNED_A_NODE) {
766 dbg_err("Not a valid node");
767 goto out_err;
768 }
769 if (cs_node->ch.node_type != UBIFS_CS_NODE) {
770 dbg_err("Node a CS node, type is %d", cs_node->ch.node_type);
771 goto out_err;
772 }
773 if (le64_to_cpu(cs_node->cmt_no) != c->cmt_no) {
774 dbg_err("CS node cmt_no %llu != current cmt_no %llu",
775 (unsigned long long)le64_to_cpu(cs_node->cmt_no),
776 c->cmt_no);
777 goto out_err;
778 }
779 *cs_sqnum = le64_to_cpu(cs_node->ch.sqnum);
780 dbg_rcvry("commit start sqnum %llu", *cs_sqnum);
781 kfree(cs_node);
782 return 0;
783
784out_err:
785 err = -EINVAL;
786out_free:
787 ubifs_err("failed to get CS sqnum");
788 kfree(cs_node);
789 return err;
790}
791
792/**
793 * ubifs_recover_log_leb - scan and recover a log LEB.
794 * @c: UBIFS file-system description object
795 * @lnum: LEB number
796 * @offs: offset
797 * @sbuf: LEB-sized buffer to use
798 *
799 * This function does a scan of a LEB, but caters for errors that might have
800 * been caused by the unclean unmount from which we are attempting to recover.
801 *
802 * This function returns %0 on success and a negative error code on failure.
803 */
804struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum,
805 int offs, void *sbuf)
806{
807 struct ubifs_scan_leb *sleb;
808 int next_lnum;
809
810 dbg_rcvry("LEB %d", lnum);
811 next_lnum = lnum + 1;
812 if (next_lnum >= UBIFS_LOG_LNUM + c->log_lebs)
813 next_lnum = UBIFS_LOG_LNUM;
814 if (next_lnum != c->ltail_lnum) {
815 /*
816 * We can only recover at the end of the log, so check that the
817 * next log LEB is empty or out of date.
818 */
819 sleb = ubifs_scan(c, next_lnum, 0, sbuf);
820 if (IS_ERR(sleb))
821 return sleb;
822 if (sleb->nodes_cnt) {
823 struct ubifs_scan_node *snod;
824 unsigned long long cs_sqnum = c->cs_sqnum;
825
826 snod = list_entry(sleb->nodes.next,
827 struct ubifs_scan_node, list);
828 if (cs_sqnum == 0) {
829 int err;
830
831 err = get_cs_sqnum(c, lnum, offs, &cs_sqnum);
832 if (err) {
833 ubifs_scan_destroy(sleb);
834 return ERR_PTR(err);
835 }
836 }
837 if (snod->sqnum > cs_sqnum) {
838 ubifs_err("unrecoverable log corruption "
839 "in LEB %d", lnum);
840 ubifs_scan_destroy(sleb);
841 return ERR_PTR(-EUCLEAN);
842 }
843 }
844 ubifs_scan_destroy(sleb);
845 }
846 return ubifs_recover_leb(c, lnum, offs, sbuf, 0);
847}
848
849/**
850 * recover_head - recover a head.
851 * @c: UBIFS file-system description object
852 * @lnum: LEB number of head to recover
853 * @offs: offset of head to recover
854 * @sbuf: LEB-sized buffer to use
855 *
856 * This function ensures that there is no data on the flash at a head location.
857 *
858 * This function returns %0 on success and a negative error code on failure.
859 */
860static int recover_head(const struct ubifs_info *c, int lnum, int offs,
861 void *sbuf)
862{
863 int len, err, need_clean = 0;
864
865 if (c->min_io_size > 1)
866 len = c->min_io_size;
867 else
868 len = 512;
869 if (offs + len > c->leb_size)
870 len = c->leb_size - offs;
871
872 if (!len)
873 return 0;
874
875 /* Read at the head location and check it is empty flash */
876 err = ubi_read(c->ubi, lnum, sbuf, offs, len);
877 if (err)
878 need_clean = 1;
879 else {
880 uint8_t *p = sbuf;
881
882 while (len--)
883 if (*p++ != 0xff) {
884 need_clean = 1;
885 break;
886 }
887 }
888
889 if (need_clean) {
890 dbg_rcvry("cleaning head at %d:%d", lnum, offs);
891 if (offs == 0)
892 return ubifs_leb_unmap(c, lnum);
893 err = ubi_read(c->ubi, lnum, sbuf, 0, offs);
894 if (err)
895 return err;
896 return ubi_leb_change(c->ubi, lnum, sbuf, offs, UBI_UNKNOWN);
897 }
898
899 return 0;
900}
901
902/**
903 * ubifs_recover_inl_heads - recover index and LPT heads.
904 * @c: UBIFS file-system description object
905 * @sbuf: LEB-sized buffer to use
906 *
907 * This function ensures that there is no data on the flash at the index and
908 * LPT head locations.
909 *
910 * This deals with the recovery of a half-completed journal commit. UBIFS is
911 * careful never to overwrite the last version of the index or the LPT. Because
912 * the index and LPT are wandering trees, data from a half-completed commit will
913 * not be referenced anywhere in UBIFS. The data will be either in LEBs that are
914 * assumed to be empty and will be unmapped anyway before use, or in the index
915 * and LPT heads.
916 *
917 * This function returns %0 on success and a negative error code on failure.
918 */
919int ubifs_recover_inl_heads(const struct ubifs_info *c, void *sbuf)
920{
921 int err;
922
923 ubifs_assert(!(c->vfs_sb->s_flags & MS_RDONLY) || c->remounting_rw);
924
925 dbg_rcvry("checking index head at %d:%d", c->ihead_lnum, c->ihead_offs);
926 err = recover_head(c, c->ihead_lnum, c->ihead_offs, sbuf);
927 if (err)
928 return err;
929
930 dbg_rcvry("checking LPT head at %d:%d", c->nhead_lnum, c->nhead_offs);
931 err = recover_head(c, c->nhead_lnum, c->nhead_offs, sbuf);
932 if (err)
933 return err;
934
935 return 0;
936}
937
938/**
939 * clean_an_unclean_leb - read and write a LEB to remove corruption.
940 * @c: UBIFS file-system description object
941 * @ucleb: unclean LEB information
942 * @sbuf: LEB-sized buffer to use
943 *
944 * This function reads a LEB up to a point pre-determined by the mount recovery,
945 * checks the nodes, and writes the result back to the flash, thereby cleaning
946 * off any following corruption, or non-fatal ECC errors.
947 *
948 * This function returns %0 on success and a negative error code on failure.
949 */
950static int clean_an_unclean_leb(const struct ubifs_info *c,
951 struct ubifs_unclean_leb *ucleb, void *sbuf)
952{
953 int err, lnum = ucleb->lnum, offs = 0, len = ucleb->endpt, quiet = 1;
954 void *buf = sbuf;
955
956 dbg_rcvry("LEB %d len %d", lnum, len);
957
958 if (len == 0) {
959 /* Nothing to read, just unmap it */
960 err = ubifs_leb_unmap(c, lnum);
961 if (err)
962 return err;
963 return 0;
964 }
965
966 err = ubi_read(c->ubi, lnum, buf, offs, len);
967 if (err && err != -EBADMSG)
968 return err;
969
970 while (len >= 8) {
971 int ret;
972
973 cond_resched();
974
975 /* Scan quietly until there is an error */
976 ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet);
977
978 if (ret == SCANNED_A_NODE) {
979 /* A valid node, and not a padding node */
980 struct ubifs_ch *ch = buf;
981 int node_len;
982
983 node_len = ALIGN(le32_to_cpu(ch->len), 8);
984 offs += node_len;
985 buf += node_len;
986 len -= node_len;
987 continue;
988 }
989
990 if (ret > 0) {
991 /* Padding bytes or a valid padding node */
992 offs += ret;
993 buf += ret;
994 len -= ret;
995 continue;
996 }
997
998 if (ret == SCANNED_EMPTY_SPACE) {
999 ubifs_err("unexpected empty space at %d:%d",
1000 lnum, offs);
1001 return -EUCLEAN;
1002 }
1003
1004 if (quiet) {
1005 /* Redo the last scan but noisily */
1006 quiet = 0;
1007 continue;
1008 }
1009
1010 ubifs_scanned_corruption(c, lnum, offs, buf);
1011 return -EUCLEAN;
1012 }
1013
1014 /* Pad to min_io_size */
1015 len = ALIGN(ucleb->endpt, c->min_io_size);
1016 if (len > ucleb->endpt) {
1017 int pad_len = len - ALIGN(ucleb->endpt, 8);
1018
1019 if (pad_len > 0) {
1020 buf = c->sbuf + len - pad_len;
1021 ubifs_pad(c, buf, pad_len);
1022 }
1023 }
1024
1025 /* Write back the LEB atomically */
1026 err = ubi_leb_change(c->ubi, lnum, sbuf, len, UBI_UNKNOWN);
1027 if (err)
1028 return err;
1029
1030 dbg_rcvry("cleaned LEB %d", lnum);
1031
1032 return 0;
1033}
1034
1035/**
1036 * ubifs_clean_lebs - clean LEBs recovered during read-only mount.
1037 * @c: UBIFS file-system description object
1038 * @sbuf: LEB-sized buffer to use
1039 *
1040 * This function cleans a LEB identified during recovery that needs to be
1041 * written but was not because UBIFS was mounted read-only. This happens when
1042 * remounting to read-write mode.
1043 *
1044 * This function returns %0 on success and a negative error code on failure.
1045 */
1046int ubifs_clean_lebs(const struct ubifs_info *c, void *sbuf)
1047{
1048 dbg_rcvry("recovery");
1049 while (!list_empty(&c->unclean_leb_list)) {
1050 struct ubifs_unclean_leb *ucleb;
1051 int err;
1052
1053 ucleb = list_entry(c->unclean_leb_list.next,
1054 struct ubifs_unclean_leb, list);
1055 err = clean_an_unclean_leb(c, ucleb, sbuf);
1056 if (err)
1057 return err;
1058 list_del(&ucleb->list);
1059 kfree(ucleb);
1060 }
1061 return 0;
1062}
1063
1064/**
1065 * ubifs_rcvry_gc_commit - recover the GC LEB number and run the commit.
1066 * @c: UBIFS file-system description object
1067 *
1068 * Out-of-place garbage collection requires always one empty LEB with which to
1069 * start garbage collection. The LEB number is recorded in c->gc_lnum and is
1070 * written to the master node on unmounting. In the case of an unclean unmount
1071 * the value of gc_lnum recorded in the master node is out of date and cannot
1072 * be used. Instead, recovery must allocate an empty LEB for this purpose.
1073 * However, there may not be enough empty space, in which case it must be
1074 * possible to GC the dirtiest LEB into the GC head LEB.
1075 *
1076 * This function also runs the commit which causes the TNC updates from
1077 * size-recovery and orphans to be written to the flash. That is important to
1078 * ensure correct replay order for subsequent mounts.
1079 *
1080 * This function returns %0 on success and a negative error code on failure.
1081 */
1082int ubifs_rcvry_gc_commit(struct ubifs_info *c)
1083{
1084 struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
1085 struct ubifs_lprops lp;
1086 int lnum, err;
1087
1088 c->gc_lnum = -1;
1089 if (wbuf->lnum == -1) {
1090 dbg_rcvry("no GC head LEB");
1091 goto find_free;
1092 }
1093 /*
1094 * See whether the used space in the dirtiest LEB fits in the GC head
1095 * LEB.
1096 */
1097 if (wbuf->offs == c->leb_size) {
1098 dbg_rcvry("no room in GC head LEB");
1099 goto find_free;
1100 }
1101 err = ubifs_find_dirty_leb(c, &lp, wbuf->offs, 2);
1102 if (err) {
1103 if (err == -ENOSPC)
1104 dbg_err("could not find a dirty LEB");
1105 return err;
1106 }
1107 ubifs_assert(!(lp.flags & LPROPS_INDEX));
1108 lnum = lp.lnum;
1109 if (lp.free + lp.dirty == c->leb_size) {
1110 /* An empty LEB was returned */
1111 if (lp.free != c->leb_size) {
1112 err = ubifs_change_one_lp(c, lnum, c->leb_size,
1113 0, 0, 0, 0);
1114 if (err)
1115 return err;
1116 }
1117 err = ubifs_leb_unmap(c, lnum);
1118 if (err)
1119 return err;
1120 c->gc_lnum = lnum;
1121 dbg_rcvry("allocated LEB %d for GC", lnum);
1122 /* Run the commit */
1123 dbg_rcvry("committing");
1124 return ubifs_run_commit(c);
1125 }
1126 /*
1127 * There was no empty LEB so the used space in the dirtiest LEB must fit
1128 * in the GC head LEB.
1129 */
1130 if (lp.free + lp.dirty < wbuf->offs) {
1131 dbg_rcvry("LEB %d doesn't fit in GC head LEB %d:%d",
1132 lnum, wbuf->lnum, wbuf->offs);
1133 err = ubifs_return_leb(c, lnum);
1134 if (err)
1135 return err;
1136 goto find_free;
1137 }
1138 /*
1139 * We run the commit before garbage collection otherwise subsequent
1140 * mounts will see the GC and orphan deletion in a different order.
1141 */
1142 dbg_rcvry("committing");
1143 err = ubifs_run_commit(c);
1144 if (err)
1145 return err;
1146 /*
1147 * The data in the dirtiest LEB fits in the GC head LEB, so do the GC
1148 * - use locking to keep 'ubifs_assert()' happy.
1149 */
1150 dbg_rcvry("GC'ing LEB %d", lnum);
1151 mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
1152 err = ubifs_garbage_collect_leb(c, &lp);
1153 if (err >= 0) {
1154 int err2 = ubifs_wbuf_sync_nolock(wbuf);
1155
1156 if (err2)
1157 err = err2;
1158 }
1159 mutex_unlock(&wbuf->io_mutex);
1160 if (err < 0) {
1161 dbg_err("GC failed, error %d", err);
1162 if (err == -EAGAIN)
1163 err = -EINVAL;
1164 return err;
1165 }
1166 if (err != LEB_RETAINED) {
1167 dbg_err("GC returned %d", err);
1168 return -EINVAL;
1169 }
1170 err = ubifs_leb_unmap(c, c->gc_lnum);
1171 if (err)
1172 return err;
1173 dbg_rcvry("allocated LEB %d for GC", lnum);
1174 return 0;
1175
1176find_free:
1177 /*
1178 * There is no GC head LEB or the free space in the GC head LEB is too
1179 * small. Allocate gc_lnum by calling 'ubifs_find_free_leb_for_idx()' so
1180 * GC is not run.
1181 */
1182 lnum = ubifs_find_free_leb_for_idx(c);
1183 if (lnum < 0) {
1184 dbg_err("could not find an empty LEB");
1185 return lnum;
1186 }
1187 /* And reset the index flag */
1188 err = ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
1189 LPROPS_INDEX, 0);
1190 if (err)
1191 return err;
1192 c->gc_lnum = lnum;
1193 dbg_rcvry("allocated LEB %d for GC", lnum);
1194 /* Run the commit */
1195 dbg_rcvry("committing");
1196 return ubifs_run_commit(c);
1197}
1198
1199/**
1200 * struct size_entry - inode size information for recovery.
1201 * @rb: link in the RB-tree of sizes
1202 * @inum: inode number
1203 * @i_size: size on inode
1204 * @d_size: maximum size based on data nodes
1205 * @exists: indicates whether the inode exists
1206 * @inode: inode if pinned in memory awaiting rw mode to fix it
1207 */
1208struct size_entry {
1209 struct rb_node rb;
1210 ino_t inum;
1211 loff_t i_size;
1212 loff_t d_size;
1213 int exists;
1214 struct inode *inode;
1215};
1216
1217/**
1218 * add_ino - add an entry to the size tree.
1219 * @c: UBIFS file-system description object
1220 * @inum: inode number
1221 * @i_size: size on inode
1222 * @d_size: maximum size based on data nodes
1223 * @exists: indicates whether the inode exists
1224 */
1225static int add_ino(struct ubifs_info *c, ino_t inum, loff_t i_size,
1226 loff_t d_size, int exists)
1227{
1228 struct rb_node **p = &c->size_tree.rb_node, *parent = NULL;
1229 struct size_entry *e;
1230
1231 while (*p) {
1232 parent = *p;
1233 e = rb_entry(parent, struct size_entry, rb);
1234 if (inum < e->inum)
1235 p = &(*p)->rb_left;
1236 else
1237 p = &(*p)->rb_right;
1238 }
1239
1240 e = kzalloc(sizeof(struct size_entry), GFP_KERNEL);
1241 if (!e)
1242 return -ENOMEM;
1243
1244 e->inum = inum;
1245 e->i_size = i_size;
1246 e->d_size = d_size;
1247 e->exists = exists;
1248
1249 rb_link_node(&e->rb, parent, p);
1250 rb_insert_color(&e->rb, &c->size_tree);
1251
1252 return 0;
1253}
1254
1255/**
1256 * find_ino - find an entry on the size tree.
1257 * @c: UBIFS file-system description object
1258 * @inum: inode number
1259 */
1260static struct size_entry *find_ino(struct ubifs_info *c, ino_t inum)
1261{
1262 struct rb_node *p = c->size_tree.rb_node;
1263 struct size_entry *e;
1264
1265 while (p) {
1266 e = rb_entry(p, struct size_entry, rb);
1267 if (inum < e->inum)
1268 p = p->rb_left;
1269 else if (inum > e->inum)
1270 p = p->rb_right;
1271 else
1272 return e;
1273 }
1274 return NULL;
1275}
1276
1277/**
1278 * remove_ino - remove an entry from the size tree.
1279 * @c: UBIFS file-system description object
1280 * @inum: inode number
1281 */
1282static void remove_ino(struct ubifs_info *c, ino_t inum)
1283{
1284 struct size_entry *e = find_ino(c, inum);
1285
1286 if (!e)
1287 return;
1288 rb_erase(&e->rb, &c->size_tree);
1289 kfree(e);
1290}
1291
1292/**
1293 * ubifs_destroy_size_tree - free resources related to the size tree.
1294 * @c: UBIFS file-system description object
1295 */
1296void ubifs_destroy_size_tree(struct ubifs_info *c)
1297{
1298 struct rb_node *this = c->size_tree.rb_node;
1299 struct size_entry *e;
1300
1301 while (this) {
1302 if (this->rb_left) {
1303 this = this->rb_left;
1304 continue;
1305 } else if (this->rb_right) {
1306 this = this->rb_right;
1307 continue;
1308 }
1309 e = rb_entry(this, struct size_entry, rb);
1310 if (e->inode)
1311 iput(e->inode);
1312 this = rb_parent(this);
1313 if (this) {
1314 if (this->rb_left == &e->rb)
1315 this->rb_left = NULL;
1316 else
1317 this->rb_right = NULL;
1318 }
1319 kfree(e);
1320 }
1321 c->size_tree = RB_ROOT;
1322}
1323
1324/**
1325 * ubifs_recover_size_accum - accumulate inode sizes for recovery.
1326 * @c: UBIFS file-system description object
1327 * @key: node key
1328 * @deletion: node is for a deletion
1329 * @new_size: inode size
1330 *
1331 * This function has two purposes:
1332 * 1) to ensure there are no data nodes that fall outside the inode size
1333 * 2) to ensure there are no data nodes for inodes that do not exist
1334 * To accomplish those purposes, a rb-tree is constructed containing an entry
1335 * for each inode number in the journal that has not been deleted, and recording
1336 * the size from the inode node, the maximum size of any data node (also altered
1337 * by truncations) and a flag indicating a inode number for which no inode node
1338 * was present in the journal.
1339 *
1340 * Note that there is still the possibility that there are data nodes that have
1341 * been committed that are beyond the inode size, however the only way to find
1342 * them would be to scan the entire index. Alternatively, some provision could
1343 * be made to record the size of inodes at the start of commit, which would seem
1344 * very cumbersome for a scenario that is quite unlikely and the only negative
1345 * consequence of which is wasted space.
1346 *
1347 * This functions returns %0 on success and a negative error code on failure.
1348 */
1349int ubifs_recover_size_accum(struct ubifs_info *c, union ubifs_key *key,
1350 int deletion, loff_t new_size)
1351{
1352 ino_t inum = key_inum(c, key);
1353 struct size_entry *e;
1354 int err;
1355
1356 switch (key_type(c, key)) {
1357 case UBIFS_INO_KEY:
1358 if (deletion)
1359 remove_ino(c, inum);
1360 else {
1361 e = find_ino(c, inum);
1362 if (e) {
1363 e->i_size = new_size;
1364 e->exists = 1;
1365 } else {
1366 err = add_ino(c, inum, new_size, 0, 1);
1367 if (err)
1368 return err;
1369 }
1370 }
1371 break;
1372 case UBIFS_DATA_KEY:
1373 e = find_ino(c, inum);
1374 if (e) {
1375 if (new_size > e->d_size)
1376 e->d_size = new_size;
1377 } else {
1378 err = add_ino(c, inum, 0, new_size, 0);
1379 if (err)
1380 return err;
1381 }
1382 break;
1383 case UBIFS_TRUN_KEY:
1384 e = find_ino(c, inum);
1385 if (e)
1386 e->d_size = new_size;
1387 break;
1388 }
1389 return 0;
1390}
1391
1392/**
1393 * fix_size_in_place - fix inode size in place on flash.
1394 * @c: UBIFS file-system description object
1395 * @e: inode size information for recovery
1396 */
1397static int fix_size_in_place(struct ubifs_info *c, struct size_entry *e)
1398{
1399 struct ubifs_ino_node *ino = c->sbuf;
1400 unsigned char *p;
1401 union ubifs_key key;
1402 int err, lnum, offs, len;
1403 loff_t i_size;
1404 uint32_t crc;
1405
1406 /* Locate the inode node LEB number and offset */
1407 ino_key_init(c, &key, e->inum);
1408 err = ubifs_tnc_locate(c, &key, ino, &lnum, &offs);
1409 if (err)
1410 goto out;
1411 /*
1412 * If the size recorded on the inode node is greater than the size that
1413 * was calculated from nodes in the journal then don't change the inode.
1414 */
1415 i_size = le64_to_cpu(ino->size);
1416 if (i_size >= e->d_size)
1417 return 0;
1418 /* Read the LEB */
1419 err = ubi_read(c->ubi, lnum, c->sbuf, 0, c->leb_size);
1420 if (err)
1421 goto out;
1422 /* Change the size field and recalculate the CRC */
1423 ino = c->sbuf + offs;
1424 ino->size = cpu_to_le64(e->d_size);
1425 len = le32_to_cpu(ino->ch.len);
1426 crc = crc32(UBIFS_CRC32_INIT, (void *)ino + 8, len - 8);
1427 ino->ch.crc = cpu_to_le32(crc);
1428 /* Work out where data in the LEB ends and free space begins */
1429 p = c->sbuf;
1430 len = c->leb_size - 1;
1431 while (p[len] == 0xff)
1432 len -= 1;
1433 len = ALIGN(len + 1, c->min_io_size);
1434 /* Atomically write the fixed LEB back again */
1435 err = ubi_leb_change(c->ubi, lnum, c->sbuf, len, UBI_UNKNOWN);
1436 if (err)
1437 goto out;
1438 dbg_rcvry("inode %lu at %d:%d size %lld -> %lld ", e->inum, lnum, offs,
1439 i_size, e->d_size);
1440 return 0;
1441
1442out:
1443 ubifs_warn("inode %lu failed to fix size %lld -> %lld error %d",
1444 e->inum, e->i_size, e->d_size, err);
1445 return err;
1446}
1447
1448/**
1449 * ubifs_recover_size - recover inode size.
1450 * @c: UBIFS file-system description object
1451 *
1452 * This function attempts to fix inode size discrepancies identified by the
1453 * 'ubifs_recover_size_accum()' function.
1454 *
1455 * This functions returns %0 on success and a negative error code on failure.
1456 */
1457int ubifs_recover_size(struct ubifs_info *c)
1458{
1459 struct rb_node *this = rb_first(&c->size_tree);
1460
1461 while (this) {
1462 struct size_entry *e;
1463 int err;
1464
1465 e = rb_entry(this, struct size_entry, rb);
1466 if (!e->exists) {
1467 union ubifs_key key;
1468
1469 ino_key_init(c, &key, e->inum);
1470 err = ubifs_tnc_lookup(c, &key, c->sbuf);
1471 if (err && err != -ENOENT)
1472 return err;
1473 if (err == -ENOENT) {
1474 /* Remove data nodes that have no inode */
1475 dbg_rcvry("removing ino %lu", e->inum);
1476 err = ubifs_tnc_remove_ino(c, e->inum);
1477 if (err)
1478 return err;
1479 } else {
1480 struct ubifs_ino_node *ino = c->sbuf;
1481
1482 e->exists = 1;
1483 e->i_size = le64_to_cpu(ino->size);
1484 }
1485 }
1486 if (e->exists && e->i_size < e->d_size) {
1487 if (!e->inode && (c->vfs_sb->s_flags & MS_RDONLY)) {
1488 /* Fix the inode size and pin it in memory */
1489 struct inode *inode;
1490
1491 inode = ubifs_iget(c->vfs_sb, e->inum);
1492 if (IS_ERR(inode))
1493 return PTR_ERR(inode);
1494 if (inode->i_size < e->d_size) {
1495 dbg_rcvry("ino %lu size %lld -> %lld",
1496 e->inum, e->d_size,
1497 inode->i_size);
1498 inode->i_size = e->d_size;
1499 ubifs_inode(inode)->ui_size = e->d_size;
1500 e->inode = inode;
1501 this = rb_next(this);
1502 continue;
1503 }
1504 iput(inode);
1505 } else {
1506 /* Fix the size in place */
1507 err = fix_size_in_place(c, e);
1508 if (err)
1509 return err;
1510 if (e->inode)
1511 iput(e->inode);
1512 }
1513 }
1514 this = rb_next(this);
1515 rb_erase(&e->rb, &c->size_tree);
1516 kfree(e);
1517 }
1518 return 0;
1519}
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-16 15:07:57 -0500