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1e51764a AB |
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 | * Author: Adrian Hunter | |
20 | */ | |
21 | ||
22 | #include "ubifs.h" | |
23 | ||
24 | /* | |
25 | * An orphan is an inode number whose inode node has been committed to the index | |
26 | * with a link count of zero. That happens when an open file is deleted | |
27 | * (unlinked) and then a commit is run. In the normal course of events the inode | |
28 | * would be deleted when the file is closed. However in the case of an unclean | |
29 | * unmount, orphans need to be accounted for. After an unclean unmount, the | |
30 | * orphans' inodes must be deleted which means either scanning the entire index | |
31 | * looking for them, or keeping a list on flash somewhere. This unit implements | |
32 | * the latter approach. | |
33 | * | |
34 | * The orphan area is a fixed number of LEBs situated between the LPT area and | |
35 | * the main area. The number of orphan area LEBs is specified when the file | |
36 | * system is created. The minimum number is 1. The size of the orphan area | |
37 | * should be so that it can hold the maximum number of orphans that are expected | |
38 | * to ever exist at one time. | |
39 | * | |
40 | * The number of orphans that can fit in a LEB is: | |
41 | * | |
42 | * (c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64) | |
43 | * | |
44 | * For example: a 15872 byte LEB can fit 1980 orphans so 1 LEB may be enough. | |
45 | * | |
46 | * Orphans are accumulated in a rb-tree. When an inode's link count drops to | |
47 | * zero, the inode number is added to the rb-tree. It is removed from the tree | |
48 | * when the inode is deleted. Any new orphans that are in the orphan tree when | |
49 | * the commit is run, are written to the orphan area in 1 or more orph nodes. | |
50 | * If the orphan area is full, it is consolidated to make space. There is | |
51 | * always enough space because validation prevents the user from creating more | |
52 | * than the maximum number of orphans allowed. | |
53 | */ | |
54 | ||
55 | #ifdef CONFIG_UBIFS_FS_DEBUG | |
56 | static int dbg_check_orphans(struct ubifs_info *c); | |
57 | #else | |
58 | #define dbg_check_orphans(c) 0 | |
59 | #endif | |
60 | ||
61 | /** | |
62 | * ubifs_add_orphan - add an orphan. | |
63 | * @c: UBIFS file-system description object | |
64 | * @inum: orphan inode number | |
65 | * | |
66 | * Add an orphan. This function is called when an inodes link count drops to | |
67 | * zero. | |
68 | */ | |
69 | int ubifs_add_orphan(struct ubifs_info *c, ino_t inum) | |
70 | { | |
71 | struct ubifs_orphan *orphan, *o; | |
72 | struct rb_node **p, *parent = NULL; | |
73 | ||
74 | orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_NOFS); | |
75 | if (!orphan) | |
76 | return -ENOMEM; | |
77 | orphan->inum = inum; | |
78 | orphan->new = 1; | |
79 | ||
80 | spin_lock(&c->orphan_lock); | |
81 | if (c->tot_orphans >= c->max_orphans) { | |
82 | spin_unlock(&c->orphan_lock); | |
83 | kfree(orphan); | |
84 | return -ENFILE; | |
85 | } | |
86 | p = &c->orph_tree.rb_node; | |
87 | while (*p) { | |
88 | parent = *p; | |
89 | o = rb_entry(parent, struct ubifs_orphan, rb); | |
90 | if (inum < o->inum) | |
91 | p = &(*p)->rb_left; | |
92 | else if (inum > o->inum) | |
93 | p = &(*p)->rb_right; | |
94 | else { | |
95 | dbg_err("orphaned twice"); | |
96 | spin_unlock(&c->orphan_lock); | |
97 | kfree(orphan); | |
98 | return 0; | |
99 | } | |
100 | } | |
101 | c->tot_orphans += 1; | |
102 | c->new_orphans += 1; | |
103 | rb_link_node(&orphan->rb, parent, p); | |
104 | rb_insert_color(&orphan->rb, &c->orph_tree); | |
105 | list_add_tail(&orphan->list, &c->orph_list); | |
106 | list_add_tail(&orphan->new_list, &c->orph_new); | |
107 | spin_unlock(&c->orphan_lock); | |
108 | dbg_gen("ino %lu", inum); | |
109 | return 0; | |
110 | } | |
111 | ||
112 | /** | |
113 | * ubifs_delete_orphan - delete an orphan. | |
114 | * @c: UBIFS file-system description object | |
115 | * @inum: orphan inode number | |
116 | * | |
117 | * Delete an orphan. This function is called when an inode is deleted. | |
118 | */ | |
119 | void ubifs_delete_orphan(struct ubifs_info *c, ino_t inum) | |
120 | { | |
121 | struct ubifs_orphan *o; | |
122 | struct rb_node *p; | |
123 | ||
124 | spin_lock(&c->orphan_lock); | |
125 | p = c->orph_tree.rb_node; | |
126 | while (p) { | |
127 | o = rb_entry(p, struct ubifs_orphan, rb); | |
128 | if (inum < o->inum) | |
129 | p = p->rb_left; | |
130 | else if (inum > o->inum) | |
131 | p = p->rb_right; | |
132 | else { | |
133 | if (o->dnext) { | |
134 | spin_unlock(&c->orphan_lock); | |
135 | dbg_gen("deleted twice ino %lu", inum); | |
136 | return; | |
137 | } | |
138 | if (o->cnext) { | |
139 | o->dnext = c->orph_dnext; | |
140 | c->orph_dnext = o; | |
141 | spin_unlock(&c->orphan_lock); | |
142 | dbg_gen("delete later ino %lu", inum); | |
143 | return; | |
144 | } | |
145 | rb_erase(p, &c->orph_tree); | |
146 | list_del(&o->list); | |
147 | c->tot_orphans -= 1; | |
148 | if (o->new) { | |
149 | list_del(&o->new_list); | |
150 | c->new_orphans -= 1; | |
151 | } | |
152 | spin_unlock(&c->orphan_lock); | |
153 | kfree(o); | |
154 | dbg_gen("inum %lu", inum); | |
155 | return; | |
156 | } | |
157 | } | |
158 | spin_unlock(&c->orphan_lock); | |
159 | dbg_err("missing orphan ino %lu", inum); | |
160 | dbg_dump_stack(); | |
161 | } | |
162 | ||
163 | /** | |
164 | * ubifs_orphan_start_commit - start commit of orphans. | |
165 | * @c: UBIFS file-system description object | |
166 | * | |
167 | * Start commit of orphans. | |
168 | */ | |
169 | int ubifs_orphan_start_commit(struct ubifs_info *c) | |
170 | { | |
171 | struct ubifs_orphan *orphan, **last; | |
172 | ||
173 | spin_lock(&c->orphan_lock); | |
174 | last = &c->orph_cnext; | |
175 | list_for_each_entry(orphan, &c->orph_new, new_list) { | |
176 | ubifs_assert(orphan->new); | |
177 | orphan->new = 0; | |
178 | *last = orphan; | |
179 | last = &orphan->cnext; | |
180 | } | |
181 | *last = orphan->cnext; | |
182 | c->cmt_orphans = c->new_orphans; | |
183 | c->new_orphans = 0; | |
184 | dbg_cmt("%d orphans to commit", c->cmt_orphans); | |
185 | INIT_LIST_HEAD(&c->orph_new); | |
186 | if (c->tot_orphans == 0) | |
187 | c->no_orphs = 1; | |
188 | else | |
189 | c->no_orphs = 0; | |
190 | spin_unlock(&c->orphan_lock); | |
191 | return 0; | |
192 | } | |
193 | ||
194 | /** | |
195 | * avail_orphs - calculate available space. | |
196 | * @c: UBIFS file-system description object | |
197 | * | |
198 | * This function returns the number of orphans that can be written in the | |
199 | * available space. | |
200 | */ | |
201 | static int avail_orphs(struct ubifs_info *c) | |
202 | { | |
203 | int avail_lebs, avail, gap; | |
204 | ||
205 | avail_lebs = c->orph_lebs - (c->ohead_lnum - c->orph_first) - 1; | |
206 | avail = avail_lebs * | |
207 | ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64)); | |
208 | gap = c->leb_size - c->ohead_offs; | |
209 | if (gap >= UBIFS_ORPH_NODE_SZ + sizeof(__le64)) | |
210 | avail += (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64); | |
211 | return avail; | |
212 | } | |
213 | ||
214 | /** | |
215 | * tot_avail_orphs - calculate total space. | |
216 | * @c: UBIFS file-system description object | |
217 | * | |
218 | * This function returns the number of orphans that can be written in half | |
219 | * the total space. That leaves half the space for adding new orphans. | |
220 | */ | |
221 | static int tot_avail_orphs(struct ubifs_info *c) | |
222 | { | |
223 | int avail_lebs, avail; | |
224 | ||
225 | avail_lebs = c->orph_lebs; | |
226 | avail = avail_lebs * | |
227 | ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64)); | |
228 | return avail / 2; | |
229 | } | |
230 | ||
231 | /** | |
232 | * do_write_orph_node - write a node | |
233 | * @c: UBIFS file-system description object | |
234 | * @len: length of node | |
235 | * @atomic: write atomically | |
236 | * | |
237 | * This function writes a node to the orphan head from the orphan buffer. If | |
238 | * %atomic is not zero, then the write is done atomically. On success, %0 is | |
239 | * returned, otherwise a negative error code is returned. | |
240 | */ | |
241 | static int do_write_orph_node(struct ubifs_info *c, int len, int atomic) | |
242 | { | |
243 | int err = 0; | |
244 | ||
245 | if (atomic) { | |
246 | ubifs_assert(c->ohead_offs == 0); | |
247 | ubifs_prepare_node(c, c->orph_buf, len, 1); | |
248 | len = ALIGN(len, c->min_io_size); | |
249 | err = ubifs_leb_change(c, c->ohead_lnum, c->orph_buf, len, | |
250 | UBI_SHORTTERM); | |
251 | } else { | |
252 | if (c->ohead_offs == 0) { | |
253 | /* Ensure LEB has been unmapped */ | |
254 | err = ubifs_leb_unmap(c, c->ohead_lnum); | |
255 | if (err) | |
256 | return err; | |
257 | } | |
258 | err = ubifs_write_node(c, c->orph_buf, len, c->ohead_lnum, | |
259 | c->ohead_offs, UBI_SHORTTERM); | |
260 | } | |
261 | return err; | |
262 | } | |
263 | ||
264 | /** | |
265 | * write_orph_node - write an orph node | |
266 | * @c: UBIFS file-system description object | |
267 | * @atomic: write atomically | |
268 | * | |
269 | * This function builds an orph node from the cnext list and writes it to the | |
270 | * orphan head. On success, %0 is returned, otherwise a negative error code | |
271 | * is returned. | |
272 | */ | |
273 | static int write_orph_node(struct ubifs_info *c, int atomic) | |
274 | { | |
275 | struct ubifs_orphan *orphan, *cnext; | |
276 | struct ubifs_orph_node *orph; | |
277 | int gap, err, len, cnt, i; | |
278 | ||
279 | ubifs_assert(c->cmt_orphans > 0); | |
280 | gap = c->leb_size - c->ohead_offs; | |
281 | if (gap < UBIFS_ORPH_NODE_SZ + sizeof(__le64)) { | |
282 | c->ohead_lnum += 1; | |
283 | c->ohead_offs = 0; | |
284 | gap = c->leb_size; | |
285 | if (c->ohead_lnum > c->orph_last) { | |
286 | /* | |
287 | * We limit the number of orphans so that this should | |
288 | * never happen. | |
289 | */ | |
290 | ubifs_err("out of space in orphan area"); | |
291 | return -EINVAL; | |
292 | } | |
293 | } | |
294 | cnt = (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64); | |
295 | if (cnt > c->cmt_orphans) | |
296 | cnt = c->cmt_orphans; | |
297 | len = UBIFS_ORPH_NODE_SZ + cnt * sizeof(__le64); | |
298 | ubifs_assert(c->orph_buf); | |
299 | orph = c->orph_buf; | |
300 | orph->ch.node_type = UBIFS_ORPH_NODE; | |
301 | spin_lock(&c->orphan_lock); | |
302 | cnext = c->orph_cnext; | |
303 | for (i = 0; i < cnt; i++) { | |
304 | orphan = cnext; | |
305 | orph->inos[i] = cpu_to_le64(orphan->inum); | |
306 | cnext = orphan->cnext; | |
307 | orphan->cnext = NULL; | |
308 | } | |
309 | c->orph_cnext = cnext; | |
310 | c->cmt_orphans -= cnt; | |
311 | spin_unlock(&c->orphan_lock); | |
312 | if (c->cmt_orphans) | |
014eb04b | 313 | orph->cmt_no = cpu_to_le64(c->cmt_no); |
1e51764a AB |
314 | else |
315 | /* Mark the last node of the commit */ | |
014eb04b | 316 | orph->cmt_no = cpu_to_le64((c->cmt_no) | (1ULL << 63)); |
1e51764a AB |
317 | ubifs_assert(c->ohead_offs + len <= c->leb_size); |
318 | ubifs_assert(c->ohead_lnum >= c->orph_first); | |
319 | ubifs_assert(c->ohead_lnum <= c->orph_last); | |
320 | err = do_write_orph_node(c, len, atomic); | |
321 | c->ohead_offs += ALIGN(len, c->min_io_size); | |
322 | c->ohead_offs = ALIGN(c->ohead_offs, 8); | |
323 | return err; | |
324 | } | |
325 | ||
326 | /** | |
327 | * write_orph_nodes - write orph nodes until there are no more to commit | |
328 | * @c: UBIFS file-system description object | |
329 | * @atomic: write atomically | |
330 | * | |
331 | * This function writes orph nodes for all the orphans to commit. On success, | |
332 | * %0 is returned, otherwise a negative error code is returned. | |
333 | */ | |
334 | static int write_orph_nodes(struct ubifs_info *c, int atomic) | |
335 | { | |
336 | int err; | |
337 | ||
338 | while (c->cmt_orphans > 0) { | |
339 | err = write_orph_node(c, atomic); | |
340 | if (err) | |
341 | return err; | |
342 | } | |
343 | if (atomic) { | |
344 | int lnum; | |
345 | ||
346 | /* Unmap any unused LEBs after consolidation */ | |
347 | lnum = c->ohead_lnum + 1; | |
348 | for (lnum = c->ohead_lnum + 1; lnum <= c->orph_last; lnum++) { | |
349 | err = ubifs_leb_unmap(c, lnum); | |
350 | if (err) | |
351 | return err; | |
352 | } | |
353 | } | |
354 | return 0; | |
355 | } | |
356 | ||
357 | /** | |
358 | * consolidate - consolidate the orphan area. | |
359 | * @c: UBIFS file-system description object | |
360 | * | |
361 | * This function enables consolidation by putting all the orphans into the list | |
362 | * to commit. The list is in the order that the orphans were added, and the | |
363 | * LEBs are written atomically in order, so at no time can orphans be lost by | |
364 | * an unclean unmount. | |
365 | * | |
366 | * This function returns %0 on success and a negative error code on failure. | |
367 | */ | |
368 | static int consolidate(struct ubifs_info *c) | |
369 | { | |
370 | int tot_avail = tot_avail_orphs(c), err = 0; | |
371 | ||
372 | spin_lock(&c->orphan_lock); | |
373 | dbg_cmt("there is space for %d orphans and there are %d", | |
374 | tot_avail, c->tot_orphans); | |
375 | if (c->tot_orphans - c->new_orphans <= tot_avail) { | |
376 | struct ubifs_orphan *orphan, **last; | |
377 | int cnt = 0; | |
378 | ||
379 | /* Change the cnext list to include all non-new orphans */ | |
380 | last = &c->orph_cnext; | |
381 | list_for_each_entry(orphan, &c->orph_list, list) { | |
382 | if (orphan->new) | |
383 | continue; | |
384 | *last = orphan; | |
385 | last = &orphan->cnext; | |
386 | cnt += 1; | |
387 | } | |
388 | *last = orphan->cnext; | |
389 | ubifs_assert(cnt == c->tot_orphans - c->new_orphans); | |
390 | c->cmt_orphans = cnt; | |
391 | c->ohead_lnum = c->orph_first; | |
392 | c->ohead_offs = 0; | |
393 | } else { | |
394 | /* | |
395 | * We limit the number of orphans so that this should | |
396 | * never happen. | |
397 | */ | |
398 | ubifs_err("out of space in orphan area"); | |
399 | err = -EINVAL; | |
400 | } | |
401 | spin_unlock(&c->orphan_lock); | |
402 | return err; | |
403 | } | |
404 | ||
405 | /** | |
406 | * commit_orphans - commit orphans. | |
407 | * @c: UBIFS file-system description object | |
408 | * | |
409 | * This function commits orphans to flash. On success, %0 is returned, | |
410 | * otherwise a negative error code is returned. | |
411 | */ | |
412 | static int commit_orphans(struct ubifs_info *c) | |
413 | { | |
414 | int avail, atomic = 0, err; | |
415 | ||
416 | ubifs_assert(c->cmt_orphans > 0); | |
417 | avail = avail_orphs(c); | |
418 | if (avail < c->cmt_orphans) { | |
419 | /* Not enough space to write new orphans, so consolidate */ | |
420 | err = consolidate(c); | |
421 | if (err) | |
422 | return err; | |
423 | atomic = 1; | |
424 | } | |
425 | err = write_orph_nodes(c, atomic); | |
426 | return err; | |
427 | } | |
428 | ||
429 | /** | |
430 | * erase_deleted - erase the orphans marked for deletion. | |
431 | * @c: UBIFS file-system description object | |
432 | * | |
433 | * During commit, the orphans being committed cannot be deleted, so they are | |
434 | * marked for deletion and deleted by this function. Also, the recovery | |
435 | * adds killed orphans to the deletion list, and therefore they are deleted | |
436 | * here too. | |
437 | */ | |
438 | static void erase_deleted(struct ubifs_info *c) | |
439 | { | |
440 | struct ubifs_orphan *orphan, *dnext; | |
441 | ||
442 | spin_lock(&c->orphan_lock); | |
443 | dnext = c->orph_dnext; | |
444 | while (dnext) { | |
445 | orphan = dnext; | |
446 | dnext = orphan->dnext; | |
447 | ubifs_assert(!orphan->new); | |
448 | rb_erase(&orphan->rb, &c->orph_tree); | |
449 | list_del(&orphan->list); | |
450 | c->tot_orphans -= 1; | |
451 | dbg_gen("deleting orphan ino %lu", orphan->inum); | |
452 | kfree(orphan); | |
453 | } | |
454 | c->orph_dnext = NULL; | |
455 | spin_unlock(&c->orphan_lock); | |
456 | } | |
457 | ||
458 | /** | |
459 | * ubifs_orphan_end_commit - end commit of orphans. | |
460 | * @c: UBIFS file-system description object | |
461 | * | |
462 | * End commit of orphans. | |
463 | */ | |
464 | int ubifs_orphan_end_commit(struct ubifs_info *c) | |
465 | { | |
466 | int err; | |
467 | ||
468 | if (c->cmt_orphans != 0) { | |
469 | err = commit_orphans(c); | |
470 | if (err) | |
471 | return err; | |
472 | } | |
473 | erase_deleted(c); | |
474 | err = dbg_check_orphans(c); | |
475 | return err; | |
476 | } | |
477 | ||
478 | /** | |
479 | * clear_orphans - erase all LEBs used for orphans. | |
480 | * @c: UBIFS file-system description object | |
481 | * | |
482 | * If recovery is not required, then the orphans from the previous session | |
483 | * are not needed. This function locates the LEBs used to record | |
484 | * orphans, and un-maps them. | |
485 | */ | |
486 | static int clear_orphans(struct ubifs_info *c) | |
487 | { | |
488 | int lnum, err; | |
489 | ||
490 | for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { | |
491 | err = ubifs_leb_unmap(c, lnum); | |
492 | if (err) | |
493 | return err; | |
494 | } | |
495 | c->ohead_lnum = c->orph_first; | |
496 | c->ohead_offs = 0; | |
497 | return 0; | |
498 | } | |
499 | ||
500 | /** | |
501 | * insert_dead_orphan - insert an orphan. | |
502 | * @c: UBIFS file-system description object | |
503 | * @inum: orphan inode number | |
504 | * | |
505 | * This function is a helper to the 'do_kill_orphans()' function. The orphan | |
506 | * must be kept until the next commit, so it is added to the rb-tree and the | |
507 | * deletion list. | |
508 | */ | |
509 | static int insert_dead_orphan(struct ubifs_info *c, ino_t inum) | |
510 | { | |
511 | struct ubifs_orphan *orphan, *o; | |
512 | struct rb_node **p, *parent = NULL; | |
513 | ||
514 | orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_KERNEL); | |
515 | if (!orphan) | |
516 | return -ENOMEM; | |
517 | orphan->inum = inum; | |
518 | ||
519 | p = &c->orph_tree.rb_node; | |
520 | while (*p) { | |
521 | parent = *p; | |
522 | o = rb_entry(parent, struct ubifs_orphan, rb); | |
523 | if (inum < o->inum) | |
524 | p = &(*p)->rb_left; | |
525 | else if (inum > o->inum) | |
526 | p = &(*p)->rb_right; | |
527 | else { | |
528 | /* Already added - no problem */ | |
529 | kfree(orphan); | |
530 | return 0; | |
531 | } | |
532 | } | |
533 | c->tot_orphans += 1; | |
534 | rb_link_node(&orphan->rb, parent, p); | |
535 | rb_insert_color(&orphan->rb, &c->orph_tree); | |
536 | list_add_tail(&orphan->list, &c->orph_list); | |
537 | orphan->dnext = c->orph_dnext; | |
538 | c->orph_dnext = orphan; | |
539 | dbg_mnt("ino %lu, new %d, tot %d", | |
540 | inum, c->new_orphans, c->tot_orphans); | |
541 | return 0; | |
542 | } | |
543 | ||
544 | /** | |
545 | * do_kill_orphans - remove orphan inodes from the index. | |
546 | * @c: UBIFS file-system description object | |
547 | * @sleb: scanned LEB | |
548 | * @last_cmt_no: cmt_no of last orph node read is passed and returned here | |
549 | * @outofdate: whether the LEB is out of date is returned here | |
550 | * @last_flagged: whether the end orph node is encountered | |
551 | * | |
552 | * This function is a helper to the 'kill_orphans()' function. It goes through | |
553 | * every orphan node in a LEB and for every inode number recorded, removes | |
554 | * all keys for that inode from the TNC. | |
555 | */ | |
556 | static int do_kill_orphans(struct ubifs_info *c, struct ubifs_scan_leb *sleb, | |
557 | unsigned long long *last_cmt_no, int *outofdate, | |
558 | int *last_flagged) | |
559 | { | |
560 | struct ubifs_scan_node *snod; | |
561 | struct ubifs_orph_node *orph; | |
562 | unsigned long long cmt_no; | |
563 | ino_t inum; | |
564 | int i, n, err, first = 1; | |
565 | ||
566 | list_for_each_entry(snod, &sleb->nodes, list) { | |
567 | if (snod->type != UBIFS_ORPH_NODE) { | |
568 | ubifs_err("invalid node type %d in orphan area at " | |
569 | "%d:%d", snod->type, sleb->lnum, snod->offs); | |
570 | dbg_dump_node(c, snod->node); | |
571 | return -EINVAL; | |
572 | } | |
573 | ||
574 | orph = snod->node; | |
575 | ||
576 | /* Check commit number */ | |
577 | cmt_no = le64_to_cpu(orph->cmt_no) & LLONG_MAX; | |
578 | /* | |
579 | * The commit number on the master node may be less, because | |
580 | * of a failed commit. If there are several failed commits in a | |
581 | * row, the commit number written on orph nodes will continue to | |
582 | * increase (because the commit number is adjusted here) even | |
583 | * though the commit number on the master node stays the same | |
584 | * because the master node has not been re-written. | |
585 | */ | |
586 | if (cmt_no > c->cmt_no) | |
587 | c->cmt_no = cmt_no; | |
588 | if (cmt_no < *last_cmt_no && *last_flagged) { | |
589 | /* | |
590 | * The last orph node had a higher commit number and was | |
591 | * flagged as the last written for that commit number. | |
592 | * That makes this orph node, out of date. | |
593 | */ | |
594 | if (!first) { | |
595 | ubifs_err("out of order commit number %llu in " | |
596 | "orphan node at %d:%d", | |
597 | cmt_no, sleb->lnum, snod->offs); | |
598 | dbg_dump_node(c, snod->node); | |
599 | return -EINVAL; | |
600 | } | |
601 | dbg_rcvry("out of date LEB %d", sleb->lnum); | |
602 | *outofdate = 1; | |
603 | return 0; | |
604 | } | |
605 | ||
606 | if (first) | |
607 | first = 0; | |
608 | ||
609 | n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3; | |
610 | for (i = 0; i < n; i++) { | |
611 | inum = le64_to_cpu(orph->inos[i]); | |
612 | dbg_rcvry("deleting orphaned inode %lu", inum); | |
613 | err = ubifs_tnc_remove_ino(c, inum); | |
614 | if (err) | |
615 | return err; | |
616 | err = insert_dead_orphan(c, inum); | |
617 | if (err) | |
618 | return err; | |
619 | } | |
620 | ||
621 | *last_cmt_no = cmt_no; | |
622 | if (le64_to_cpu(orph->cmt_no) & (1ULL << 63)) { | |
623 | dbg_rcvry("last orph node for commit %llu at %d:%d", | |
624 | cmt_no, sleb->lnum, snod->offs); | |
625 | *last_flagged = 1; | |
626 | } else | |
627 | *last_flagged = 0; | |
628 | } | |
629 | ||
630 | return 0; | |
631 | } | |
632 | ||
633 | /** | |
634 | * kill_orphans - remove all orphan inodes from the index. | |
635 | * @c: UBIFS file-system description object | |
636 | * | |
637 | * If recovery is required, then orphan inodes recorded during the previous | |
638 | * session (which ended with an unclean unmount) must be deleted from the index. | |
639 | * This is done by updating the TNC, but since the index is not updated until | |
640 | * the next commit, the LEBs where the orphan information is recorded are not | |
641 | * erased until the next commit. | |
642 | */ | |
643 | static int kill_orphans(struct ubifs_info *c) | |
644 | { | |
645 | unsigned long long last_cmt_no = 0; | |
646 | int lnum, err = 0, outofdate = 0, last_flagged = 0; | |
647 | ||
648 | c->ohead_lnum = c->orph_first; | |
649 | c->ohead_offs = 0; | |
650 | /* Check no-orphans flag and skip this if no orphans */ | |
651 | if (c->no_orphs) { | |
652 | dbg_rcvry("no orphans"); | |
653 | return 0; | |
654 | } | |
655 | /* | |
656 | * Orph nodes always start at c->orph_first and are written to each | |
657 | * successive LEB in turn. Generally unused LEBs will have been unmapped | |
658 | * but may contain out of date orph nodes if the unmap didn't go | |
659 | * through. In addition, the last orph node written for each commit is | |
660 | * marked (top bit of orph->cmt_no is set to 1). It is possible that | |
661 | * there are orph nodes from the next commit (i.e. the commit did not | |
662 | * complete successfully). In that case, no orphans will have been lost | |
663 | * due to the way that orphans are written, and any orphans added will | |
664 | * be valid orphans anyway and so can be deleted. | |
665 | */ | |
666 | for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { | |
667 | struct ubifs_scan_leb *sleb; | |
668 | ||
669 | dbg_rcvry("LEB %d", lnum); | |
670 | sleb = ubifs_scan(c, lnum, 0, c->sbuf); | |
671 | if (IS_ERR(sleb)) { | |
672 | sleb = ubifs_recover_leb(c, lnum, 0, c->sbuf, 0); | |
673 | if (IS_ERR(sleb)) { | |
674 | err = PTR_ERR(sleb); | |
675 | break; | |
676 | } | |
677 | } | |
678 | err = do_kill_orphans(c, sleb, &last_cmt_no, &outofdate, | |
679 | &last_flagged); | |
680 | if (err || outofdate) { | |
681 | ubifs_scan_destroy(sleb); | |
682 | break; | |
683 | } | |
684 | if (sleb->endpt) { | |
685 | c->ohead_lnum = lnum; | |
686 | c->ohead_offs = sleb->endpt; | |
687 | } | |
688 | ubifs_scan_destroy(sleb); | |
689 | } | |
690 | return err; | |
691 | } | |
692 | ||
693 | /** | |
694 | * ubifs_mount_orphans - delete orphan inodes and erase LEBs that recorded them. | |
695 | * @c: UBIFS file-system description object | |
696 | * @unclean: indicates recovery from unclean unmount | |
697 | * @read_only: indicates read only mount | |
698 | * | |
699 | * This function is called when mounting to erase orphans from the previous | |
700 | * session. If UBIFS was not unmounted cleanly, then the inodes recorded as | |
701 | * orphans are deleted. | |
702 | */ | |
703 | int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only) | |
704 | { | |
705 | int err = 0; | |
706 | ||
707 | c->max_orphans = tot_avail_orphs(c); | |
708 | ||
709 | if (!read_only) { | |
710 | c->orph_buf = vmalloc(c->leb_size); | |
711 | if (!c->orph_buf) | |
712 | return -ENOMEM; | |
713 | } | |
714 | ||
715 | if (unclean) | |
716 | err = kill_orphans(c); | |
717 | else if (!read_only) | |
718 | err = clear_orphans(c); | |
719 | ||
720 | return err; | |
721 | } | |
722 | ||
723 | #ifdef CONFIG_UBIFS_FS_DEBUG | |
724 | ||
725 | struct check_orphan { | |
726 | struct rb_node rb; | |
727 | ino_t inum; | |
728 | }; | |
729 | ||
730 | struct check_info { | |
731 | unsigned long last_ino; | |
732 | unsigned long tot_inos; | |
733 | unsigned long missing; | |
734 | unsigned long long leaf_cnt; | |
735 | struct ubifs_ino_node *node; | |
736 | struct rb_root root; | |
737 | }; | |
738 | ||
739 | static int dbg_find_orphan(struct ubifs_info *c, ino_t inum) | |
740 | { | |
741 | struct ubifs_orphan *o; | |
742 | struct rb_node *p; | |
743 | ||
744 | spin_lock(&c->orphan_lock); | |
745 | p = c->orph_tree.rb_node; | |
746 | while (p) { | |
747 | o = rb_entry(p, struct ubifs_orphan, rb); | |
748 | if (inum < o->inum) | |
749 | p = p->rb_left; | |
750 | else if (inum > o->inum) | |
751 | p = p->rb_right; | |
752 | else { | |
753 | spin_unlock(&c->orphan_lock); | |
754 | return 1; | |
755 | } | |
756 | } | |
757 | spin_unlock(&c->orphan_lock); | |
758 | return 0; | |
759 | } | |
760 | ||
761 | static int dbg_ins_check_orphan(struct rb_root *root, ino_t inum) | |
762 | { | |
763 | struct check_orphan *orphan, *o; | |
764 | struct rb_node **p, *parent = NULL; | |
765 | ||
766 | orphan = kzalloc(sizeof(struct check_orphan), GFP_NOFS); | |
767 | if (!orphan) | |
768 | return -ENOMEM; | |
769 | orphan->inum = inum; | |
770 | ||
771 | p = &root->rb_node; | |
772 | while (*p) { | |
773 | parent = *p; | |
774 | o = rb_entry(parent, struct check_orphan, rb); | |
775 | if (inum < o->inum) | |
776 | p = &(*p)->rb_left; | |
777 | else if (inum > o->inum) | |
778 | p = &(*p)->rb_right; | |
779 | else { | |
780 | kfree(orphan); | |
781 | return 0; | |
782 | } | |
783 | } | |
784 | rb_link_node(&orphan->rb, parent, p); | |
785 | rb_insert_color(&orphan->rb, root); | |
786 | return 0; | |
787 | } | |
788 | ||
789 | static int dbg_find_check_orphan(struct rb_root *root, ino_t inum) | |
790 | { | |
791 | struct check_orphan *o; | |
792 | struct rb_node *p; | |
793 | ||
794 | p = root->rb_node; | |
795 | while (p) { | |
796 | o = rb_entry(p, struct check_orphan, rb); | |
797 | if (inum < o->inum) | |
798 | p = p->rb_left; | |
799 | else if (inum > o->inum) | |
800 | p = p->rb_right; | |
801 | else | |
802 | return 1; | |
803 | } | |
804 | return 0; | |
805 | } | |
806 | ||
807 | static void dbg_free_check_tree(struct rb_root *root) | |
808 | { | |
809 | struct rb_node *this = root->rb_node; | |
810 | struct check_orphan *o; | |
811 | ||
812 | while (this) { | |
813 | if (this->rb_left) { | |
814 | this = this->rb_left; | |
815 | continue; | |
816 | } else if (this->rb_right) { | |
817 | this = this->rb_right; | |
818 | continue; | |
819 | } | |
820 | o = rb_entry(this, struct check_orphan, rb); | |
821 | this = rb_parent(this); | |
822 | if (this) { | |
823 | if (this->rb_left == &o->rb) | |
824 | this->rb_left = NULL; | |
825 | else | |
826 | this->rb_right = NULL; | |
827 | } | |
828 | kfree(o); | |
829 | } | |
830 | } | |
831 | ||
832 | static int dbg_orphan_check(struct ubifs_info *c, struct ubifs_zbranch *zbr, | |
833 | void *priv) | |
834 | { | |
835 | struct check_info *ci = priv; | |
836 | ino_t inum; | |
837 | int err; | |
838 | ||
839 | inum = key_inum(c, &zbr->key); | |
840 | if (inum != ci->last_ino) { | |
841 | /* Lowest node type is the inode node, so it comes first */ | |
842 | if (key_type(c, &zbr->key) != UBIFS_INO_KEY) | |
843 | ubifs_err("found orphan node ino %lu, type %d", inum, | |
844 | key_type(c, &zbr->key)); | |
845 | ci->last_ino = inum; | |
846 | ci->tot_inos += 1; | |
847 | err = ubifs_tnc_read_node(c, zbr, ci->node); | |
848 | if (err) { | |
849 | ubifs_err("node read failed, error %d", err); | |
850 | return err; | |
851 | } | |
852 | if (ci->node->nlink == 0) | |
853 | /* Must be recorded as an orphan */ | |
854 | if (!dbg_find_check_orphan(&ci->root, inum) && | |
855 | !dbg_find_orphan(c, inum)) { | |
856 | ubifs_err("missing orphan, ino %lu", inum); | |
857 | ci->missing += 1; | |
858 | } | |
859 | } | |
860 | ci->leaf_cnt += 1; | |
861 | return 0; | |
862 | } | |
863 | ||
864 | static int dbg_read_orphans(struct check_info *ci, struct ubifs_scan_leb *sleb) | |
865 | { | |
866 | struct ubifs_scan_node *snod; | |
867 | struct ubifs_orph_node *orph; | |
868 | ino_t inum; | |
869 | int i, n, err; | |
870 | ||
871 | list_for_each_entry(snod, &sleb->nodes, list) { | |
872 | cond_resched(); | |
873 | if (snod->type != UBIFS_ORPH_NODE) | |
874 | continue; | |
875 | orph = snod->node; | |
876 | n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3; | |
877 | for (i = 0; i < n; i++) { | |
878 | inum = le64_to_cpu(orph->inos[i]); | |
879 | err = dbg_ins_check_orphan(&ci->root, inum); | |
880 | if (err) | |
881 | return err; | |
882 | } | |
883 | } | |
884 | return 0; | |
885 | } | |
886 | ||
887 | static int dbg_scan_orphans(struct ubifs_info *c, struct check_info *ci) | |
888 | { | |
889 | int lnum, err = 0; | |
890 | ||
891 | /* Check no-orphans flag and skip this if no orphans */ | |
892 | if (c->no_orphs) | |
893 | return 0; | |
894 | ||
895 | for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { | |
896 | struct ubifs_scan_leb *sleb; | |
897 | ||
898 | sleb = ubifs_scan(c, lnum, 0, c->dbg_buf); | |
899 | if (IS_ERR(sleb)) { | |
900 | err = PTR_ERR(sleb); | |
901 | break; | |
902 | } | |
903 | ||
904 | err = dbg_read_orphans(ci, sleb); | |
905 | ubifs_scan_destroy(sleb); | |
906 | if (err) | |
907 | break; | |
908 | } | |
909 | ||
910 | return err; | |
911 | } | |
912 | ||
913 | static int dbg_check_orphans(struct ubifs_info *c) | |
914 | { | |
915 | struct check_info ci; | |
916 | int err; | |
917 | ||
918 | if (!(ubifs_chk_flags & UBIFS_CHK_ORPH)) | |
919 | return 0; | |
920 | ||
921 | ci.last_ino = 0; | |
922 | ci.tot_inos = 0; | |
923 | ci.missing = 0; | |
924 | ci.leaf_cnt = 0; | |
925 | ci.root = RB_ROOT; | |
926 | ci.node = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS); | |
927 | if (!ci.node) { | |
928 | ubifs_err("out of memory"); | |
929 | return -ENOMEM; | |
930 | } | |
931 | ||
932 | err = dbg_scan_orphans(c, &ci); | |
933 | if (err) | |
934 | goto out; | |
935 | ||
936 | err = dbg_walk_index(c, &dbg_orphan_check, NULL, &ci); | |
937 | if (err) { | |
938 | ubifs_err("cannot scan TNC, error %d", err); | |
939 | goto out; | |
940 | } | |
941 | ||
942 | if (ci.missing) { | |
943 | ubifs_err("%lu missing orphan(s)", ci.missing); | |
944 | err = -EINVAL; | |
945 | goto out; | |
946 | } | |
947 | ||
948 | dbg_cmt("last inode number is %lu", ci.last_ino); | |
949 | dbg_cmt("total number of inodes is %lu", ci.tot_inos); | |
950 | dbg_cmt("total number of leaf nodes is %llu", ci.leaf_cnt); | |
951 | ||
952 | out: | |
953 | dbg_free_check_tree(&ci.root); | |
954 | kfree(ci.node); | |
955 | return err; | |
956 | } | |
957 | ||
958 | #endif /* CONFIG_UBIFS_FS_DEBUG */ |