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1 /*
2 * This file is part of UBIFS.
3 *
4 * Copyright (C) 2006-2008 Nokia Corporation.
5 *
6 * SPDX-License-Identifier: GPL-2.0+
7 *
8 * Author: Adrian Hunter
9 */
10
11 #include <linux/err.h>
12 #include "ubifs.h"
13
14 /*
15 * An orphan is an inode number whose inode node has been committed to the index
16 * with a link count of zero. That happens when an open file is deleted
17 * (unlinked) and then a commit is run. In the normal course of events the inode
18 * would be deleted when the file is closed. However in the case of an unclean
19 * unmount, orphans need to be accounted for. After an unclean unmount, the
20 * orphans' inodes must be deleted which means either scanning the entire index
21 * looking for them, or keeping a list on flash somewhere. This unit implements
22 * the latter approach.
23 *
24 * The orphan area is a fixed number of LEBs situated between the LPT area and
25 * the main area. The number of orphan area LEBs is specified when the file
26 * system is created. The minimum number is 1. The size of the orphan area
27 * should be so that it can hold the maximum number of orphans that are expected
28 * to ever exist at one time.
29 *
30 * The number of orphans that can fit in a LEB is:
31 *
32 * (c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64)
33 *
34 * For example: a 15872 byte LEB can fit 1980 orphans so 1 LEB may be enough.
35 *
36 * Orphans are accumulated in a rb-tree. When an inode's link count drops to
37 * zero, the inode number is added to the rb-tree. It is removed from the tree
38 * when the inode is deleted. Any new orphans that are in the orphan tree when
39 * the commit is run, are written to the orphan area in 1 or more orphan nodes.
40 * If the orphan area is full, it is consolidated to make space. There is
41 * always enough space because validation prevents the user from creating more
42 * than the maximum number of orphans allowed.
43 */
44
45 static int dbg_check_orphans(struct ubifs_info *c);
46
47 /**
48 * ubifs_add_orphan - add an orphan.
49 * @c: UBIFS file-system description object
50 * @inum: orphan inode number
51 *
52 * Add an orphan. This function is called when an inodes link count drops to
53 * zero.
54 */
55 int ubifs_add_orphan(struct ubifs_info *c, ino_t inum)
56 {
57 struct ubifs_orphan *orphan, *o;
58 struct rb_node **p, *parent = NULL;
59
60 orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_NOFS);
61 if (!orphan)
62 return -ENOMEM;
63 orphan->inum = inum;
64 orphan->new = 1;
65
66 spin_lock(&c->orphan_lock);
67 if (c->tot_orphans >= c->max_orphans) {
68 spin_unlock(&c->orphan_lock);
69 kfree(orphan);
70 return -ENFILE;
71 }
72 p = &c->orph_tree.rb_node;
73 while (*p) {
74 parent = *p;
75 o = rb_entry(parent, struct ubifs_orphan, rb);
76 if (inum < o->inum)
77 p = &(*p)->rb_left;
78 else if (inum > o->inum)
79 p = &(*p)->rb_right;
80 else {
81 ubifs_err(c, "orphaned twice");
82 spin_unlock(&c->orphan_lock);
83 kfree(orphan);
84 return 0;
85 }
86 }
87 c->tot_orphans += 1;
88 c->new_orphans += 1;
89 rb_link_node(&orphan->rb, parent, p);
90 rb_insert_color(&orphan->rb, &c->orph_tree);
91 list_add_tail(&orphan->list, &c->orph_list);
92 list_add_tail(&orphan->new_list, &c->orph_new);
93 spin_unlock(&c->orphan_lock);
94 dbg_gen("ino %lu", (unsigned long)inum);
95 return 0;
96 }
97
98 /**
99 * ubifs_delete_orphan - delete an orphan.
100 * @c: UBIFS file-system description object
101 * @inum: orphan inode number
102 *
103 * Delete an orphan. This function is called when an inode is deleted.
104 */
105 void ubifs_delete_orphan(struct ubifs_info *c, ino_t inum)
106 {
107 struct ubifs_orphan *o;
108 struct rb_node *p;
109
110 spin_lock(&c->orphan_lock);
111 p = c->orph_tree.rb_node;
112 while (p) {
113 o = rb_entry(p, struct ubifs_orphan, rb);
114 if (inum < o->inum)
115 p = p->rb_left;
116 else if (inum > o->inum)
117 p = p->rb_right;
118 else {
119 if (o->del) {
120 spin_unlock(&c->orphan_lock);
121 dbg_gen("deleted twice ino %lu",
122 (unsigned long)inum);
123 return;
124 }
125 if (o->cmt) {
126 o->del = 1;
127 o->dnext = c->orph_dnext;
128 c->orph_dnext = o;
129 spin_unlock(&c->orphan_lock);
130 dbg_gen("delete later ino %lu",
131 (unsigned long)inum);
132 return;
133 }
134 rb_erase(p, &c->orph_tree);
135 list_del(&o->list);
136 c->tot_orphans -= 1;
137 if (o->new) {
138 list_del(&o->new_list);
139 c->new_orphans -= 1;
140 }
141 spin_unlock(&c->orphan_lock);
142 kfree(o);
143 dbg_gen("inum %lu", (unsigned long)inum);
144 return;
145 }
146 }
147 spin_unlock(&c->orphan_lock);
148 ubifs_err(c, "missing orphan ino %lu", (unsigned long)inum);
149 dump_stack();
150 }
151
152 /**
153 * ubifs_orphan_start_commit - start commit of orphans.
154 * @c: UBIFS file-system description object
155 *
156 * Start commit of orphans.
157 */
158 int ubifs_orphan_start_commit(struct ubifs_info *c)
159 {
160 struct ubifs_orphan *orphan, **last;
161
162 spin_lock(&c->orphan_lock);
163 last = &c->orph_cnext;
164 list_for_each_entry(orphan, &c->orph_new, new_list) {
165 ubifs_assert(orphan->new);
166 ubifs_assert(!orphan->cmt);
167 orphan->new = 0;
168 orphan->cmt = 1;
169 *last = orphan;
170 last = &orphan->cnext;
171 }
172 *last = NULL;
173 c->cmt_orphans = c->new_orphans;
174 c->new_orphans = 0;
175 dbg_cmt("%d orphans to commit", c->cmt_orphans);
176 INIT_LIST_HEAD(&c->orph_new);
177 if (c->tot_orphans == 0)
178 c->no_orphs = 1;
179 else
180 c->no_orphs = 0;
181 spin_unlock(&c->orphan_lock);
182 return 0;
183 }
184
185 /**
186 * avail_orphs - calculate available space.
187 * @c: UBIFS file-system description object
188 *
189 * This function returns the number of orphans that can be written in the
190 * available space.
191 */
192 static int avail_orphs(struct ubifs_info *c)
193 {
194 int avail_lebs, avail, gap;
195
196 avail_lebs = c->orph_lebs - (c->ohead_lnum - c->orph_first) - 1;
197 avail = avail_lebs *
198 ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64));
199 gap = c->leb_size - c->ohead_offs;
200 if (gap >= UBIFS_ORPH_NODE_SZ + sizeof(__le64))
201 avail += (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64);
202 return avail;
203 }
204
205 /**
206 * tot_avail_orphs - calculate total space.
207 * @c: UBIFS file-system description object
208 *
209 * This function returns the number of orphans that can be written in half
210 * the total space. That leaves half the space for adding new orphans.
211 */
212 static int tot_avail_orphs(struct ubifs_info *c)
213 {
214 int avail_lebs, avail;
215
216 avail_lebs = c->orph_lebs;
217 avail = avail_lebs *
218 ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64));
219 return avail / 2;
220 }
221
222 /**
223 * do_write_orph_node - write a node to the orphan head.
224 * @c: UBIFS file-system description object
225 * @len: length of node
226 * @atomic: write atomically
227 *
228 * This function writes a node to the orphan head from the orphan buffer. If
229 * %atomic is not zero, then the write is done atomically. On success, %0 is
230 * returned, otherwise a negative error code is returned.
231 */
232 static int do_write_orph_node(struct ubifs_info *c, int len, int atomic)
233 {
234 int err = 0;
235
236 if (atomic) {
237 ubifs_assert(c->ohead_offs == 0);
238 ubifs_prepare_node(c, c->orph_buf, len, 1);
239 len = ALIGN(len, c->min_io_size);
240 err = ubifs_leb_change(c, c->ohead_lnum, c->orph_buf, len);
241 } else {
242 if (c->ohead_offs == 0) {
243 /* Ensure LEB has been unmapped */
244 err = ubifs_leb_unmap(c, c->ohead_lnum);
245 if (err)
246 return err;
247 }
248 err = ubifs_write_node(c, c->orph_buf, len, c->ohead_lnum,
249 c->ohead_offs);
250 }
251 return err;
252 }
253
254 /**
255 * write_orph_node - write an orphan node.
256 * @c: UBIFS file-system description object
257 * @atomic: write atomically
258 *
259 * This function builds an orphan node from the cnext list and writes it to the
260 * orphan head. On success, %0 is returned, otherwise a negative error code
261 * is returned.
262 */
263 static int write_orph_node(struct ubifs_info *c, int atomic)
264 {
265 struct ubifs_orphan *orphan, *cnext;
266 struct ubifs_orph_node *orph;
267 int gap, err, len, cnt, i;
268
269 ubifs_assert(c->cmt_orphans > 0);
270 gap = c->leb_size - c->ohead_offs;
271 if (gap < UBIFS_ORPH_NODE_SZ + sizeof(__le64)) {
272 c->ohead_lnum += 1;
273 c->ohead_offs = 0;
274 gap = c->leb_size;
275 if (c->ohead_lnum > c->orph_last) {
276 /*
277 * We limit the number of orphans so that this should
278 * never happen.
279 */
280 ubifs_err(c, "out of space in orphan area");
281 return -EINVAL;
282 }
283 }
284 cnt = (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64);
285 if (cnt > c->cmt_orphans)
286 cnt = c->cmt_orphans;
287 len = UBIFS_ORPH_NODE_SZ + cnt * sizeof(__le64);
288 ubifs_assert(c->orph_buf);
289 orph = c->orph_buf;
290 orph->ch.node_type = UBIFS_ORPH_NODE;
291 spin_lock(&c->orphan_lock);
292 cnext = c->orph_cnext;
293 for (i = 0; i < cnt; i++) {
294 orphan = cnext;
295 ubifs_assert(orphan->cmt);
296 orph->inos[i] = cpu_to_le64(orphan->inum);
297 orphan->cmt = 0;
298 cnext = orphan->cnext;
299 orphan->cnext = NULL;
300 }
301 c->orph_cnext = cnext;
302 c->cmt_orphans -= cnt;
303 spin_unlock(&c->orphan_lock);
304 if (c->cmt_orphans)
305 orph->cmt_no = cpu_to_le64(c->cmt_no);
306 else
307 /* Mark the last node of the commit */
308 orph->cmt_no = cpu_to_le64((c->cmt_no) | (1ULL << 63));
309 ubifs_assert(c->ohead_offs + len <= c->leb_size);
310 ubifs_assert(c->ohead_lnum >= c->orph_first);
311 ubifs_assert(c->ohead_lnum <= c->orph_last);
312 err = do_write_orph_node(c, len, atomic);
313 c->ohead_offs += ALIGN(len, c->min_io_size);
314 c->ohead_offs = ALIGN(c->ohead_offs, 8);
315 return err;
316 }
317
318 /**
319 * write_orph_nodes - write orphan nodes until there are no more to commit.
320 * @c: UBIFS file-system description object
321 * @atomic: write atomically
322 *
323 * This function writes orphan nodes for all the orphans to commit. On success,
324 * %0 is returned, otherwise a negative error code is returned.
325 */
326 static int write_orph_nodes(struct ubifs_info *c, int atomic)
327 {
328 int err;
329
330 while (c->cmt_orphans > 0) {
331 err = write_orph_node(c, atomic);
332 if (err)
333 return err;
334 }
335 if (atomic) {
336 int lnum;
337
338 /* Unmap any unused LEBs after consolidation */
339 for (lnum = c->ohead_lnum + 1; lnum <= c->orph_last; lnum++) {
340 err = ubifs_leb_unmap(c, lnum);
341 if (err)
342 return err;
343 }
344 }
345 return 0;
346 }
347
348 /**
349 * consolidate - consolidate the orphan area.
350 * @c: UBIFS file-system description object
351 *
352 * This function enables consolidation by putting all the orphans into the list
353 * to commit. The list is in the order that the orphans were added, and the
354 * LEBs are written atomically in order, so at no time can orphans be lost by
355 * an unclean unmount.
356 *
357 * This function returns %0 on success and a negative error code on failure.
358 */
359 static int consolidate(struct ubifs_info *c)
360 {
361 int tot_avail = tot_avail_orphs(c), err = 0;
362
363 spin_lock(&c->orphan_lock);
364 dbg_cmt("there is space for %d orphans and there are %d",
365 tot_avail, c->tot_orphans);
366 if (c->tot_orphans - c->new_orphans <= tot_avail) {
367 struct ubifs_orphan *orphan, **last;
368 int cnt = 0;
369
370 /* Change the cnext list to include all non-new orphans */
371 last = &c->orph_cnext;
372 list_for_each_entry(orphan, &c->orph_list, list) {
373 if (orphan->new)
374 continue;
375 orphan->cmt = 1;
376 *last = orphan;
377 last = &orphan->cnext;
378 cnt += 1;
379 }
380 *last = NULL;
381 ubifs_assert(cnt == c->tot_orphans - c->new_orphans);
382 c->cmt_orphans = cnt;
383 c->ohead_lnum = c->orph_first;
384 c->ohead_offs = 0;
385 } else {
386 /*
387 * We limit the number of orphans so that this should
388 * never happen.
389 */
390 ubifs_err(c, "out of space in orphan area");
391 err = -EINVAL;
392 }
393 spin_unlock(&c->orphan_lock);
394 return err;
395 }
396
397 /**
398 * commit_orphans - commit orphans.
399 * @c: UBIFS file-system description object
400 *
401 * This function commits orphans to flash. On success, %0 is returned,
402 * otherwise a negative error code is returned.
403 */
404 static int commit_orphans(struct ubifs_info *c)
405 {
406 int avail, atomic = 0, err;
407
408 ubifs_assert(c->cmt_orphans > 0);
409 avail = avail_orphs(c);
410 if (avail < c->cmt_orphans) {
411 /* Not enough space to write new orphans, so consolidate */
412 err = consolidate(c);
413 if (err)
414 return err;
415 atomic = 1;
416 }
417 err = write_orph_nodes(c, atomic);
418 return err;
419 }
420
421 /**
422 * erase_deleted - erase the orphans marked for deletion.
423 * @c: UBIFS file-system description object
424 *
425 * During commit, the orphans being committed cannot be deleted, so they are
426 * marked for deletion and deleted by this function. Also, the recovery
427 * adds killed orphans to the deletion list, and therefore they are deleted
428 * here too.
429 */
430 static void erase_deleted(struct ubifs_info *c)
431 {
432 struct ubifs_orphan *orphan, *dnext;
433
434 spin_lock(&c->orphan_lock);
435 dnext = c->orph_dnext;
436 while (dnext) {
437 orphan = dnext;
438 dnext = orphan->dnext;
439 ubifs_assert(!orphan->new);
440 ubifs_assert(orphan->del);
441 rb_erase(&orphan->rb, &c->orph_tree);
442 list_del(&orphan->list);
443 c->tot_orphans -= 1;
444 dbg_gen("deleting orphan ino %lu", (unsigned long)orphan->inum);
445 kfree(orphan);
446 }
447 c->orph_dnext = NULL;
448 spin_unlock(&c->orphan_lock);
449 }
450
451 /**
452 * ubifs_orphan_end_commit - end commit of orphans.
453 * @c: UBIFS file-system description object
454 *
455 * End commit of orphans.
456 */
457 int ubifs_orphan_end_commit(struct ubifs_info *c)
458 {
459 int err;
460
461 if (c->cmt_orphans != 0) {
462 err = commit_orphans(c);
463 if (err)
464 return err;
465 }
466 erase_deleted(c);
467 err = dbg_check_orphans(c);
468 return err;
469 }
470
471 /**
472 * ubifs_clear_orphans - erase all LEBs used for orphans.
473 * @c: UBIFS file-system description object
474 *
475 * If recovery is not required, then the orphans from the previous session
476 * are not needed. This function locates the LEBs used to record
477 * orphans, and un-maps them.
478 */
479 int ubifs_clear_orphans(struct ubifs_info *c)
480 {
481 int lnum, err;
482
483 for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
484 err = ubifs_leb_unmap(c, lnum);
485 if (err)
486 return err;
487 }
488 c->ohead_lnum = c->orph_first;
489 c->ohead_offs = 0;
490 return 0;
491 }
492
493 /**
494 * insert_dead_orphan - insert an orphan.
495 * @c: UBIFS file-system description object
496 * @inum: orphan inode number
497 *
498 * This function is a helper to the 'do_kill_orphans()' function. The orphan
499 * must be kept until the next commit, so it is added to the rb-tree and the
500 * deletion list.
501 */
502 static int insert_dead_orphan(struct ubifs_info *c, ino_t inum)
503 {
504 struct ubifs_orphan *orphan, *o;
505 struct rb_node **p, *parent = NULL;
506
507 orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_KERNEL);
508 if (!orphan)
509 return -ENOMEM;
510 orphan->inum = inum;
511
512 p = &c->orph_tree.rb_node;
513 while (*p) {
514 parent = *p;
515 o = rb_entry(parent, struct ubifs_orphan, rb);
516 if (inum < o->inum)
517 p = &(*p)->rb_left;
518 else if (inum > o->inum)
519 p = &(*p)->rb_right;
520 else {
521 /* Already added - no problem */
522 kfree(orphan);
523 return 0;
524 }
525 }
526 c->tot_orphans += 1;
527 rb_link_node(&orphan->rb, parent, p);
528 rb_insert_color(&orphan->rb, &c->orph_tree);
529 list_add_tail(&orphan->list, &c->orph_list);
530 orphan->del = 1;
531 orphan->dnext = c->orph_dnext;
532 c->orph_dnext = orphan;
533 dbg_mnt("ino %lu, new %d, tot %d", (unsigned long)inum,
534 c->new_orphans, c->tot_orphans);
535 return 0;
536 }
537
538 /**
539 * do_kill_orphans - remove orphan inodes from the index.
540 * @c: UBIFS file-system description object
541 * @sleb: scanned LEB
542 * @last_cmt_no: cmt_no of last orphan node read is passed and returned here
543 * @outofdate: whether the LEB is out of date is returned here
544 * @last_flagged: whether the end orphan node is encountered
545 *
546 * This function is a helper to the 'kill_orphans()' function. It goes through
547 * every orphan node in a LEB and for every inode number recorded, removes
548 * all keys for that inode from the TNC.
549 */
550 static int do_kill_orphans(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
551 unsigned long long *last_cmt_no, int *outofdate,
552 int *last_flagged)
553 {
554 struct ubifs_scan_node *snod;
555 struct ubifs_orph_node *orph;
556 unsigned long long cmt_no;
557 ino_t inum;
558 int i, n, err, first = 1;
559
560 list_for_each_entry(snod, &sleb->nodes, list) {
561 if (snod->type != UBIFS_ORPH_NODE) {
562 ubifs_err(c, "invalid node type %d in orphan area at %d:%d",
563 snod->type, sleb->lnum, snod->offs);
564 ubifs_dump_node(c, snod->node);
565 return -EINVAL;
566 }
567
568 orph = snod->node;
569
570 /* Check commit number */
571 cmt_no = le64_to_cpu(orph->cmt_no) & LLONG_MAX;
572 /*
573 * The commit number on the master node may be less, because
574 * of a failed commit. If there are several failed commits in a
575 * row, the commit number written on orphan nodes will continue
576 * to increase (because the commit number is adjusted here) even
577 * though the commit number on the master node stays the same
578 * because the master node has not been re-written.
579 */
580 if (cmt_no > c->cmt_no)
581 c->cmt_no = cmt_no;
582 if (cmt_no < *last_cmt_no && *last_flagged) {
583 /*
584 * The last orphan node had a higher commit number and
585 * was flagged as the last written for that commit
586 * number. That makes this orphan node, out of date.
587 */
588 if (!first) {
589 ubifs_err(c, "out of order commit number %llu in orphan node at %d:%d",
590 cmt_no, sleb->lnum, snod->offs);
591 ubifs_dump_node(c, snod->node);
592 return -EINVAL;
593 }
594 dbg_rcvry("out of date LEB %d", sleb->lnum);
595 *outofdate = 1;
596 return 0;
597 }
598
599 if (first)
600 first = 0;
601
602 n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3;
603 for (i = 0; i < n; i++) {
604 inum = le64_to_cpu(orph->inos[i]);
605 dbg_rcvry("deleting orphaned inode %lu",
606 (unsigned long)inum);
607 err = ubifs_tnc_remove_ino(c, inum);
608 if (err)
609 return err;
610 err = insert_dead_orphan(c, inum);
611 if (err)
612 return err;
613 }
614
615 *last_cmt_no = cmt_no;
616 if (le64_to_cpu(orph->cmt_no) & (1ULL << 63)) {
617 dbg_rcvry("last orph node for commit %llu at %d:%d",
618 cmt_no, sleb->lnum, snod->offs);
619 *last_flagged = 1;
620 } else
621 *last_flagged = 0;
622 }
623
624 return 0;
625 }
626
627 /**
628 * kill_orphans - remove all orphan inodes from the index.
629 * @c: UBIFS file-system description object
630 *
631 * If recovery is required, then orphan inodes recorded during the previous
632 * session (which ended with an unclean unmount) must be deleted from the index.
633 * This is done by updating the TNC, but since the index is not updated until
634 * the next commit, the LEBs where the orphan information is recorded are not
635 * erased until the next commit.
636 */
637 static int kill_orphans(struct ubifs_info *c)
638 {
639 unsigned long long last_cmt_no = 0;
640 int lnum, err = 0, outofdate = 0, last_flagged = 0;
641
642 c->ohead_lnum = c->orph_first;
643 c->ohead_offs = 0;
644 /* Check no-orphans flag and skip this if no orphans */
645 if (c->no_orphs) {
646 dbg_rcvry("no orphans");
647 return 0;
648 }
649 /*
650 * Orph nodes always start at c->orph_first and are written to each
651 * successive LEB in turn. Generally unused LEBs will have been unmapped
652 * but may contain out of date orphan nodes if the unmap didn't go
653 * through. In addition, the last orphan node written for each commit is
654 * marked (top bit of orph->cmt_no is set to 1). It is possible that
655 * there are orphan nodes from the next commit (i.e. the commit did not
656 * complete successfully). In that case, no orphans will have been lost
657 * due to the way that orphans are written, and any orphans added will
658 * be valid orphans anyway and so can be deleted.
659 */
660 for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
661 struct ubifs_scan_leb *sleb;
662
663 dbg_rcvry("LEB %d", lnum);
664 sleb = ubifs_scan(c, lnum, 0, c->sbuf, 1);
665 if (IS_ERR(sleb)) {
666 if (PTR_ERR(sleb) == -EUCLEAN)
667 sleb = ubifs_recover_leb(c, lnum, 0,
668 c->sbuf, -1);
669 if (IS_ERR(sleb)) {
670 err = PTR_ERR(sleb);
671 break;
672 }
673 }
674 err = do_kill_orphans(c, sleb, &last_cmt_no, &outofdate,
675 &last_flagged);
676 if (err || outofdate) {
677 ubifs_scan_destroy(sleb);
678 break;
679 }
680 if (sleb->endpt) {
681 c->ohead_lnum = lnum;
682 c->ohead_offs = sleb->endpt;
683 }
684 ubifs_scan_destroy(sleb);
685 }
686 return err;
687 }
688
689 /**
690 * ubifs_mount_orphans - delete orphan inodes and erase LEBs that recorded them.
691 * @c: UBIFS file-system description object
692 * @unclean: indicates recovery from unclean unmount
693 * @read_only: indicates read only mount
694 *
695 * This function is called when mounting to erase orphans from the previous
696 * session. If UBIFS was not unmounted cleanly, then the inodes recorded as
697 * orphans are deleted.
698 */
699 int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only)
700 {
701 int err = 0;
702
703 c->max_orphans = tot_avail_orphs(c);
704
705 if (!read_only) {
706 c->orph_buf = vmalloc(c->leb_size);
707 if (!c->orph_buf)
708 return -ENOMEM;
709 }
710
711 if (unclean)
712 err = kill_orphans(c);
713 else if (!read_only)
714 err = ubifs_clear_orphans(c);
715
716 return err;
717 }
718
719 /*
720 * Everything below is related to debugging.
721 */
722
723 struct check_orphan {
724 struct rb_node rb;
725 ino_t inum;
726 };
727
728 struct check_info {
729 unsigned long last_ino;
730 unsigned long tot_inos;
731 unsigned long missing;
732 unsigned long long leaf_cnt;
733 struct ubifs_ino_node *node;
734 struct rb_root root;
735 };
736
737 static int dbg_find_orphan(struct ubifs_info *c, ino_t inum)
738 {
739 struct ubifs_orphan *o;
740 struct rb_node *p;
741
742 spin_lock(&c->orphan_lock);
743 p = c->orph_tree.rb_node;
744 while (p) {
745 o = rb_entry(p, struct ubifs_orphan, rb);
746 if (inum < o->inum)
747 p = p->rb_left;
748 else if (inum > o->inum)
749 p = p->rb_right;
750 else {
751 spin_unlock(&c->orphan_lock);
752 return 1;
753 }
754 }
755 spin_unlock(&c->orphan_lock);
756 return 0;
757 }
758
759 static int dbg_ins_check_orphan(struct rb_root *root, ino_t inum)
760 {
761 struct check_orphan *orphan, *o;
762 struct rb_node **p, *parent = NULL;
763
764 orphan = kzalloc(sizeof(struct check_orphan), GFP_NOFS);
765 if (!orphan)
766 return -ENOMEM;
767 orphan->inum = inum;
768
769 p = &root->rb_node;
770 while (*p) {
771 parent = *p;
772 o = rb_entry(parent, struct check_orphan, rb);
773 if (inum < o->inum)
774 p = &(*p)->rb_left;
775 else if (inum > o->inum)
776 p = &(*p)->rb_right;
777 else {
778 kfree(orphan);
779 return 0;
780 }
781 }
782 rb_link_node(&orphan->rb, parent, p);
783 rb_insert_color(&orphan->rb, root);
784 return 0;
785 }
786
787 static int dbg_find_check_orphan(struct rb_root *root, ino_t inum)
788 {
789 struct check_orphan *o;
790 struct rb_node *p;
791
792 p = root->rb_node;
793 while (p) {
794 o = rb_entry(p, struct check_orphan, rb);
795 if (inum < o->inum)
796 p = p->rb_left;
797 else if (inum > o->inum)
798 p = p->rb_right;
799 else
800 return 1;
801 }
802 return 0;
803 }
804
805 static void dbg_free_check_tree(struct rb_root *root)
806 {
807 struct check_orphan *o, *n;
808
809 rbtree_postorder_for_each_entry_safe(o, n, root, rb)
810 kfree(o);
811 }
812
813 static int dbg_orphan_check(struct ubifs_info *c, struct ubifs_zbranch *zbr,
814 void *priv)
815 {
816 struct check_info *ci = priv;
817 ino_t inum;
818 int err;
819
820 inum = key_inum(c, &zbr->key);
821 if (inum != ci->last_ino) {
822 /* Lowest node type is the inode node, so it comes first */
823 if (key_type(c, &zbr->key) != UBIFS_INO_KEY)
824 ubifs_err(c, "found orphan node ino %lu, type %d",
825 (unsigned long)inum, key_type(c, &zbr->key));
826 ci->last_ino = inum;
827 ci->tot_inos += 1;
828 err = ubifs_tnc_read_node(c, zbr, ci->node);
829 if (err) {
830 ubifs_err(c, "node read failed, error %d", err);
831 return err;
832 }
833 if (ci->node->nlink == 0)
834 /* Must be recorded as an orphan */
835 if (!dbg_find_check_orphan(&ci->root, inum) &&
836 !dbg_find_orphan(c, inum)) {
837 ubifs_err(c, "missing orphan, ino %lu",
838 (unsigned long)inum);
839 ci->missing += 1;
840 }
841 }
842 ci->leaf_cnt += 1;
843 return 0;
844 }
845
846 static int dbg_read_orphans(struct check_info *ci, struct ubifs_scan_leb *sleb)
847 {
848 struct ubifs_scan_node *snod;
849 struct ubifs_orph_node *orph;
850 ino_t inum;
851 int i, n, err;
852
853 list_for_each_entry(snod, &sleb->nodes, list) {
854 cond_resched();
855 if (snod->type != UBIFS_ORPH_NODE)
856 continue;
857 orph = snod->node;
858 n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3;
859 for (i = 0; i < n; i++) {
860 inum = le64_to_cpu(orph->inos[i]);
861 err = dbg_ins_check_orphan(&ci->root, inum);
862 if (err)
863 return err;
864 }
865 }
866 return 0;
867 }
868
869 static int dbg_scan_orphans(struct ubifs_info *c, struct check_info *ci)
870 {
871 int lnum, err = 0;
872 void *buf;
873
874 /* Check no-orphans flag and skip this if no orphans */
875 if (c->no_orphs)
876 return 0;
877
878 buf = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL);
879 if (!buf) {
880 ubifs_err(c, "cannot allocate memory to check orphans");
881 return 0;
882 }
883
884 for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
885 struct ubifs_scan_leb *sleb;
886
887 sleb = ubifs_scan(c, lnum, 0, buf, 0);
888 if (IS_ERR(sleb)) {
889 err = PTR_ERR(sleb);
890 break;
891 }
892
893 err = dbg_read_orphans(ci, sleb);
894 ubifs_scan_destroy(sleb);
895 if (err)
896 break;
897 }
898
899 vfree(buf);
900 return err;
901 }
902
903 static int dbg_check_orphans(struct ubifs_info *c)
904 {
905 struct check_info ci;
906 int err;
907
908 if (!dbg_is_chk_orph(c))
909 return 0;
910
911 ci.last_ino = 0;
912 ci.tot_inos = 0;
913 ci.missing = 0;
914 ci.leaf_cnt = 0;
915 ci.root = RB_ROOT;
916 ci.node = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS);
917 if (!ci.node) {
918 ubifs_err(c, "out of memory");
919 return -ENOMEM;
920 }
921
922 err = dbg_scan_orphans(c, &ci);
923 if (err)
924 goto out;
925
926 err = dbg_walk_index(c, &dbg_orphan_check, NULL, &ci);
927 if (err) {
928 ubifs_err(c, "cannot scan TNC, error %d", err);
929 goto out;
930 }
931
932 if (ci.missing) {
933 ubifs_err(c, "%lu missing orphan(s)", ci.missing);
934 err = -EINVAL;
935 goto out;
936 }
937
938 dbg_cmt("last inode number is %lu", ci.last_ino);
939 dbg_cmt("total number of inodes is %lu", ci.tot_inos);
940 dbg_cmt("total number of leaf nodes is %llu", ci.leaf_cnt);
941
942 out:
943 dbg_free_check_tree(&ci.root);
944 kfree(ci.node);
945 return err;
946 }