Commit | Line | Data |
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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 | * Authors: Artem Bityutskiy (Битюцкий Артём) | |
20 | * Adrian Hunter | |
21 | */ | |
22 | ||
23 | /* | |
24 | * This file is a part of UBIFS journal implementation and contains various | |
25 | * functions which manipulate the log. The log is a fixed area on the flash | |
26 | * which does not contain any data but refers to buds. The log is a part of the | |
27 | * journal. | |
28 | */ | |
29 | ||
30 | #include "ubifs.h" | |
31 | ||
1e51764a | 32 | static int dbg_check_bud_bytes(struct ubifs_info *c); |
1e51764a AB |
33 | |
34 | /** | |
35 | * ubifs_search_bud - search bud LEB. | |
36 | * @c: UBIFS file-system description object | |
37 | * @lnum: logical eraseblock number to search | |
38 | * | |
39 | * This function searches bud LEB @lnum. Returns bud description object in case | |
40 | * of success and %NULL if there is no bud with this LEB number. | |
41 | */ | |
42 | struct ubifs_bud *ubifs_search_bud(struct ubifs_info *c, int lnum) | |
43 | { | |
44 | struct rb_node *p; | |
45 | struct ubifs_bud *bud; | |
46 | ||
47 | spin_lock(&c->buds_lock); | |
48 | p = c->buds.rb_node; | |
49 | while (p) { | |
50 | bud = rb_entry(p, struct ubifs_bud, rb); | |
51 | if (lnum < bud->lnum) | |
52 | p = p->rb_left; | |
53 | else if (lnum > bud->lnum) | |
54 | p = p->rb_right; | |
55 | else { | |
56 | spin_unlock(&c->buds_lock); | |
57 | return bud; | |
58 | } | |
59 | } | |
60 | spin_unlock(&c->buds_lock); | |
61 | return NULL; | |
62 | } | |
63 | ||
64 | /** | |
65 | * ubifs_get_wbuf - get the wbuf associated with a LEB, if there is one. | |
66 | * @c: UBIFS file-system description object | |
67 | * @lnum: logical eraseblock number to search | |
68 | * | |
69 | * This functions returns the wbuf for @lnum or %NULL if there is not one. | |
70 | */ | |
71 | struct ubifs_wbuf *ubifs_get_wbuf(struct ubifs_info *c, int lnum) | |
72 | { | |
73 | struct rb_node *p; | |
74 | struct ubifs_bud *bud; | |
75 | int jhead; | |
76 | ||
77 | if (!c->jheads) | |
78 | return NULL; | |
79 | ||
80 | spin_lock(&c->buds_lock); | |
81 | p = c->buds.rb_node; | |
82 | while (p) { | |
83 | bud = rb_entry(p, struct ubifs_bud, rb); | |
84 | if (lnum < bud->lnum) | |
85 | p = p->rb_left; | |
86 | else if (lnum > bud->lnum) | |
87 | p = p->rb_right; | |
88 | else { | |
89 | jhead = bud->jhead; | |
90 | spin_unlock(&c->buds_lock); | |
91 | return &c->jheads[jhead].wbuf; | |
92 | } | |
93 | } | |
94 | spin_unlock(&c->buds_lock); | |
95 | return NULL; | |
96 | } | |
97 | ||
1e51764a AB |
98 | /** |
99 | * empty_log_bytes - calculate amount of empty space in the log. | |
100 | * @c: UBIFS file-system description object | |
101 | */ | |
102 | static inline long long empty_log_bytes(const struct ubifs_info *c) | |
103 | { | |
104 | long long h, t; | |
105 | ||
106 | h = (long long)c->lhead_lnum * c->leb_size + c->lhead_offs; | |
107 | t = (long long)c->ltail_lnum * c->leb_size; | |
108 | ||
109 | if (h >= t) | |
110 | return c->log_bytes - h + t; | |
111 | else | |
112 | return t - h; | |
113 | } | |
114 | ||
115 | /** | |
116 | * ubifs_add_bud - add bud LEB to the tree of buds and its journal head list. | |
117 | * @c: UBIFS file-system description object | |
118 | * @bud: the bud to add | |
119 | */ | |
120 | void ubifs_add_bud(struct ubifs_info *c, struct ubifs_bud *bud) | |
121 | { | |
122 | struct rb_node **p, *parent = NULL; | |
123 | struct ubifs_bud *b; | |
124 | struct ubifs_jhead *jhead; | |
125 | ||
126 | spin_lock(&c->buds_lock); | |
127 | p = &c->buds.rb_node; | |
128 | while (*p) { | |
129 | parent = *p; | |
130 | b = rb_entry(parent, struct ubifs_bud, rb); | |
131 | ubifs_assert(bud->lnum != b->lnum); | |
132 | if (bud->lnum < b->lnum) | |
133 | p = &(*p)->rb_left; | |
134 | else | |
135 | p = &(*p)->rb_right; | |
136 | } | |
137 | ||
138 | rb_link_node(&bud->rb, parent, p); | |
139 | rb_insert_color(&bud->rb, &c->buds); | |
140 | if (c->jheads) { | |
141 | jhead = &c->jheads[bud->jhead]; | |
142 | list_add_tail(&bud->list, &jhead->buds_list); | |
143 | } else | |
2ef13294 | 144 | ubifs_assert(c->replaying && c->ro_mount); |
1e51764a AB |
145 | |
146 | /* | |
147 | * Note, although this is a new bud, we anyway account this space now, | |
148 | * before any data has been written to it, because this is about to | |
149 | * guarantee fixed mount time, and this bud will anyway be read and | |
150 | * scanned. | |
151 | */ | |
152 | c->bud_bytes += c->leb_size - bud->start; | |
153 | ||
77a7ae58 AB |
154 | dbg_log("LEB %d:%d, jhead %s, bud_bytes %lld", bud->lnum, |
155 | bud->start, dbg_jhead(bud->jhead), c->bud_bytes); | |
1e51764a AB |
156 | spin_unlock(&c->buds_lock); |
157 | } | |
158 | ||
1e51764a AB |
159 | /** |
160 | * ubifs_add_bud_to_log - add a new bud to the log. | |
161 | * @c: UBIFS file-system description object | |
162 | * @jhead: journal head the bud belongs to | |
163 | * @lnum: LEB number of the bud | |
164 | * @offs: starting offset of the bud | |
165 | * | |
166 | * This function writes reference node for the new bud LEB @lnum it to the log, | |
167 | * and adds it to the buds tress. It also makes sure that log size does not | |
168 | * exceed the 'c->max_bud_bytes' limit. Returns zero in case of success, | |
169 | * %-EAGAIN if commit is required, and a negative error codes in case of | |
170 | * failure. | |
171 | */ | |
172 | int ubifs_add_bud_to_log(struct ubifs_info *c, int jhead, int lnum, int offs) | |
173 | { | |
174 | int err; | |
175 | struct ubifs_bud *bud; | |
176 | struct ubifs_ref_node *ref; | |
177 | ||
178 | bud = kmalloc(sizeof(struct ubifs_bud), GFP_NOFS); | |
179 | if (!bud) | |
180 | return -ENOMEM; | |
181 | ref = kzalloc(c->ref_node_alsz, GFP_NOFS); | |
182 | if (!ref) { | |
183 | kfree(bud); | |
184 | return -ENOMEM; | |
185 | } | |
186 | ||
187 | mutex_lock(&c->log_mutex); | |
2ef13294 | 188 | ubifs_assert(!c->ro_media && !c->ro_mount); |
2680d722 | 189 | if (c->ro_error) { |
1e51764a AB |
190 | err = -EROFS; |
191 | goto out_unlock; | |
192 | } | |
193 | ||
194 | /* Make sure we have enough space in the log */ | |
195 | if (empty_log_bytes(c) - c->ref_node_alsz < c->min_log_bytes) { | |
196 | dbg_log("not enough log space - %lld, required %d", | |
197 | empty_log_bytes(c), c->min_log_bytes); | |
198 | ubifs_commit_required(c); | |
199 | err = -EAGAIN; | |
200 | goto out_unlock; | |
201 | } | |
202 | ||
203 | /* | |
7d4e9ccb | 204 | * Make sure the amount of space in buds will not exceed the |
1e51764a AB |
205 | * 'c->max_bud_bytes' limit, because we want to guarantee mount time |
206 | * limits. | |
207 | * | |
208 | * It is not necessary to hold @c->buds_lock when reading @c->bud_bytes | |
209 | * because we are holding @c->log_mutex. All @c->bud_bytes take place | |
210 | * when both @c->log_mutex and @c->bud_bytes are locked. | |
211 | */ | |
212 | if (c->bud_bytes + c->leb_size - offs > c->max_bud_bytes) { | |
213 | dbg_log("bud bytes %lld (%lld max), require commit", | |
214 | c->bud_bytes, c->max_bud_bytes); | |
215 | ubifs_commit_required(c); | |
216 | err = -EAGAIN; | |
217 | goto out_unlock; | |
218 | } | |
219 | ||
220 | /* | |
221 | * If the journal is full enough - start background commit. Note, it is | |
222 | * OK to read 'c->cmt_state' without spinlock because integer reads | |
223 | * are atomic in the kernel. | |
224 | */ | |
225 | if (c->bud_bytes >= c->bg_bud_bytes && | |
226 | c->cmt_state == COMMIT_RESTING) { | |
227 | dbg_log("bud bytes %lld (%lld max), initiate BG commit", | |
228 | c->bud_bytes, c->max_bud_bytes); | |
229 | ubifs_request_bg_commit(c); | |
230 | } | |
231 | ||
232 | bud->lnum = lnum; | |
233 | bud->start = offs; | |
234 | bud->jhead = jhead; | |
235 | ||
236 | ref->ch.node_type = UBIFS_REF_NODE; | |
237 | ref->lnum = cpu_to_le32(bud->lnum); | |
238 | ref->offs = cpu_to_le32(bud->start); | |
239 | ref->jhead = cpu_to_le32(jhead); | |
240 | ||
241 | if (c->lhead_offs > c->leb_size - c->ref_node_alsz) { | |
e11602ea | 242 | c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum); |
1e51764a AB |
243 | c->lhead_offs = 0; |
244 | } | |
245 | ||
246 | if (c->lhead_offs == 0) { | |
247 | /* Must ensure next log LEB has been unmapped */ | |
248 | err = ubifs_leb_unmap(c, c->lhead_lnum); | |
249 | if (err) | |
250 | goto out_unlock; | |
251 | } | |
252 | ||
253 | if (bud->start == 0) { | |
254 | /* | |
255 | * Before writing the LEB reference which refers an empty LEB | |
256 | * to the log, we have to make sure it is mapped, because | |
257 | * otherwise we'd risk to refer an LEB with garbage in case of | |
258 | * an unclean reboot, because the target LEB might have been | |
259 | * unmapped, but not yet physically erased. | |
260 | */ | |
b36a261e | 261 | err = ubifs_leb_map(c, bud->lnum); |
1e51764a AB |
262 | if (err) |
263 | goto out_unlock; | |
264 | } | |
265 | ||
266 | dbg_log("write ref LEB %d:%d", | |
267 | c->lhead_lnum, c->lhead_offs); | |
268 | err = ubifs_write_node(c, ref, UBIFS_REF_NODE_SZ, c->lhead_lnum, | |
b36a261e | 269 | c->lhead_offs); |
1e51764a AB |
270 | if (err) |
271 | goto out_unlock; | |
272 | ||
273 | c->lhead_offs += c->ref_node_alsz; | |
274 | ||
275 | ubifs_add_bud(c, bud); | |
276 | ||
277 | mutex_unlock(&c->log_mutex); | |
278 | kfree(ref); | |
279 | return 0; | |
280 | ||
281 | out_unlock: | |
282 | mutex_unlock(&c->log_mutex); | |
283 | kfree(ref); | |
284 | kfree(bud); | |
285 | return err; | |
286 | } | |
287 | ||
288 | /** | |
289 | * remove_buds - remove used buds. | |
290 | * @c: UBIFS file-system description object | |
291 | * | |
292 | * This function removes use buds from the buds tree. It does not remove the | |
293 | * buds which are pointed to by journal heads. | |
294 | */ | |
295 | static void remove_buds(struct ubifs_info *c) | |
296 | { | |
297 | struct rb_node *p; | |
298 | ||
299 | ubifs_assert(list_empty(&c->old_buds)); | |
300 | c->cmt_bud_bytes = 0; | |
301 | spin_lock(&c->buds_lock); | |
302 | p = rb_first(&c->buds); | |
303 | while (p) { | |
304 | struct rb_node *p1 = p; | |
305 | struct ubifs_bud *bud; | |
306 | struct ubifs_wbuf *wbuf; | |
307 | ||
308 | p = rb_next(p); | |
309 | bud = rb_entry(p1, struct ubifs_bud, rb); | |
310 | wbuf = &c->jheads[bud->jhead].wbuf; | |
311 | ||
312 | if (wbuf->lnum == bud->lnum) { | |
313 | /* | |
314 | * Do not remove buds which are pointed to by journal | |
315 | * heads (non-closed buds). | |
316 | */ | |
317 | c->cmt_bud_bytes += wbuf->offs - bud->start; | |
77a7ae58 | 318 | dbg_log("preserve %d:%d, jhead %s, bud bytes %d, " |
1e51764a | 319 | "cmt_bud_bytes %lld", bud->lnum, bud->start, |
77a7ae58 | 320 | dbg_jhead(bud->jhead), wbuf->offs - bud->start, |
1e51764a AB |
321 | c->cmt_bud_bytes); |
322 | bud->start = wbuf->offs; | |
323 | } else { | |
324 | c->cmt_bud_bytes += c->leb_size - bud->start; | |
77a7ae58 | 325 | dbg_log("remove %d:%d, jhead %s, bud bytes %d, " |
1e51764a | 326 | "cmt_bud_bytes %lld", bud->lnum, bud->start, |
77a7ae58 | 327 | dbg_jhead(bud->jhead), c->leb_size - bud->start, |
1e51764a AB |
328 | c->cmt_bud_bytes); |
329 | rb_erase(p1, &c->buds); | |
1e51764a AB |
330 | /* |
331 | * If the commit does not finish, the recovery will need | |
332 | * to replay the journal, in which case the old buds | |
333 | * must be unchanged. Do not release them until post | |
334 | * commit i.e. do not allow them to be garbage | |
335 | * collected. | |
336 | */ | |
ec32816f | 337 | list_move(&bud->list, &c->old_buds); |
1e51764a AB |
338 | } |
339 | } | |
340 | spin_unlock(&c->buds_lock); | |
341 | } | |
342 | ||
343 | /** | |
344 | * ubifs_log_start_commit - start commit. | |
345 | * @c: UBIFS file-system description object | |
346 | * @ltail_lnum: return new log tail LEB number | |
347 | * | |
348 | * The commit operation starts with writing "commit start" node to the log and | |
349 | * reference nodes for all journal heads which will define new journal after | |
350 | * the commit has been finished. The commit start and reference nodes are | |
351 | * written in one go to the nearest empty log LEB (hence, when commit is | |
352 | * finished UBIFS may safely unmap all the previous log LEBs). This function | |
353 | * returns zero in case of success and a negative error code in case of | |
354 | * failure. | |
355 | */ | |
356 | int ubifs_log_start_commit(struct ubifs_info *c, int *ltail_lnum) | |
357 | { | |
358 | void *buf; | |
359 | struct ubifs_cs_node *cs; | |
360 | struct ubifs_ref_node *ref; | |
361 | int err, i, max_len, len; | |
362 | ||
363 | err = dbg_check_bud_bytes(c); | |
364 | if (err) | |
365 | return err; | |
366 | ||
367 | max_len = UBIFS_CS_NODE_SZ + c->jhead_cnt * UBIFS_REF_NODE_SZ; | |
368 | max_len = ALIGN(max_len, c->min_io_size); | |
369 | buf = cs = kmalloc(max_len, GFP_NOFS); | |
370 | if (!buf) | |
371 | return -ENOMEM; | |
372 | ||
373 | cs->ch.node_type = UBIFS_CS_NODE; | |
014eb04b | 374 | cs->cmt_no = cpu_to_le64(c->cmt_no); |
1e51764a AB |
375 | ubifs_prepare_node(c, cs, UBIFS_CS_NODE_SZ, 0); |
376 | ||
377 | /* | |
378 | * Note, we do not lock 'c->log_mutex' because this is the commit start | |
379 | * phase and we are exclusively using the log. And we do not lock | |
380 | * write-buffer because nobody can write to the file-system at this | |
381 | * phase. | |
382 | */ | |
383 | ||
384 | len = UBIFS_CS_NODE_SZ; | |
385 | for (i = 0; i < c->jhead_cnt; i++) { | |
386 | int lnum = c->jheads[i].wbuf.lnum; | |
387 | int offs = c->jheads[i].wbuf.offs; | |
388 | ||
389 | if (lnum == -1 || offs == c->leb_size) | |
390 | continue; | |
391 | ||
77a7ae58 AB |
392 | dbg_log("add ref to LEB %d:%d for jhead %s", |
393 | lnum, offs, dbg_jhead(i)); | |
1e51764a AB |
394 | ref = buf + len; |
395 | ref->ch.node_type = UBIFS_REF_NODE; | |
396 | ref->lnum = cpu_to_le32(lnum); | |
397 | ref->offs = cpu_to_le32(offs); | |
398 | ref->jhead = cpu_to_le32(i); | |
399 | ||
400 | ubifs_prepare_node(c, ref, UBIFS_REF_NODE_SZ, 0); | |
401 | len += UBIFS_REF_NODE_SZ; | |
402 | } | |
403 | ||
404 | ubifs_pad(c, buf + len, ALIGN(len, c->min_io_size) - len); | |
405 | ||
406 | /* Switch to the next log LEB */ | |
407 | if (c->lhead_offs) { | |
e11602ea | 408 | c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum); |
1e51764a AB |
409 | c->lhead_offs = 0; |
410 | } | |
411 | ||
412 | if (c->lhead_offs == 0) { | |
413 | /* Must ensure next LEB has been unmapped */ | |
414 | err = ubifs_leb_unmap(c, c->lhead_lnum); | |
415 | if (err) | |
416 | goto out; | |
417 | } | |
418 | ||
419 | len = ALIGN(len, c->min_io_size); | |
420 | dbg_log("writing commit start at LEB %d:0, len %d", c->lhead_lnum, len); | |
b36a261e | 421 | err = ubifs_leb_write(c, c->lhead_lnum, cs, 0, len); |
1e51764a AB |
422 | if (err) |
423 | goto out; | |
424 | ||
425 | *ltail_lnum = c->lhead_lnum; | |
426 | ||
427 | c->lhead_offs += len; | |
428 | if (c->lhead_offs == c->leb_size) { | |
e11602ea | 429 | c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum); |
1e51764a AB |
430 | c->lhead_offs = 0; |
431 | } | |
432 | ||
433 | remove_buds(c); | |
434 | ||
435 | /* | |
436 | * We have started the commit and now users may use the rest of the log | |
437 | * for new writes. | |
438 | */ | |
439 | c->min_log_bytes = 0; | |
440 | ||
441 | out: | |
442 | kfree(buf); | |
443 | return err; | |
444 | } | |
445 | ||
446 | /** | |
447 | * ubifs_log_end_commit - end commit. | |
448 | * @c: UBIFS file-system description object | |
449 | * @ltail_lnum: new log tail LEB number | |
450 | * | |
451 | * This function is called on when the commit operation was finished. It | |
452 | * moves log tail to new position and unmaps LEBs which contain obsolete data. | |
453 | * Returns zero in case of success and a negative error code in case of | |
454 | * failure. | |
455 | */ | |
456 | int ubifs_log_end_commit(struct ubifs_info *c, int ltail_lnum) | |
457 | { | |
458 | int err; | |
459 | ||
460 | /* | |
461 | * At this phase we have to lock 'c->log_mutex' because UBIFS allows FS | |
462 | * writes during commit. Its only short "commit" start phase when | |
463 | * writers are blocked. | |
464 | */ | |
465 | mutex_lock(&c->log_mutex); | |
466 | ||
467 | dbg_log("old tail was LEB %d:0, new tail is LEB %d:0", | |
468 | c->ltail_lnum, ltail_lnum); | |
469 | ||
470 | c->ltail_lnum = ltail_lnum; | |
471 | /* | |
472 | * The commit is finished and from now on it must be guaranteed that | |
473 | * there is always enough space for the next commit. | |
474 | */ | |
475 | c->min_log_bytes = c->leb_size; | |
476 | ||
477 | spin_lock(&c->buds_lock); | |
478 | c->bud_bytes -= c->cmt_bud_bytes; | |
479 | spin_unlock(&c->buds_lock); | |
480 | ||
481 | err = dbg_check_bud_bytes(c); | |
482 | ||
483 | mutex_unlock(&c->log_mutex); | |
484 | return err; | |
485 | } | |
486 | ||
487 | /** | |
488 | * ubifs_log_post_commit - things to do after commit is completed. | |
489 | * @c: UBIFS file-system description object | |
490 | * @old_ltail_lnum: old log tail LEB number | |
491 | * | |
492 | * Release buds only after commit is completed, because they must be unchanged | |
493 | * if recovery is needed. | |
494 | * | |
495 | * Unmap log LEBs only after commit is completed, because they may be needed for | |
496 | * recovery. | |
497 | * | |
498 | * This function returns %0 on success and a negative error code on failure. | |
499 | */ | |
500 | int ubifs_log_post_commit(struct ubifs_info *c, int old_ltail_lnum) | |
501 | { | |
502 | int lnum, err = 0; | |
503 | ||
504 | while (!list_empty(&c->old_buds)) { | |
505 | struct ubifs_bud *bud; | |
506 | ||
507 | bud = list_entry(c->old_buds.next, struct ubifs_bud, list); | |
508 | err = ubifs_return_leb(c, bud->lnum); | |
509 | if (err) | |
510 | return err; | |
511 | list_del(&bud->list); | |
512 | kfree(bud); | |
513 | } | |
514 | mutex_lock(&c->log_mutex); | |
515 | for (lnum = old_ltail_lnum; lnum != c->ltail_lnum; | |
e11602ea | 516 | lnum = ubifs_next_log_lnum(c, lnum)) { |
1e51764a AB |
517 | dbg_log("unmap log LEB %d", lnum); |
518 | err = ubifs_leb_unmap(c, lnum); | |
519 | if (err) | |
520 | goto out; | |
521 | } | |
522 | out: | |
523 | mutex_unlock(&c->log_mutex); | |
524 | return err; | |
525 | } | |
526 | ||
527 | /** | |
528 | * struct done_ref - references that have been done. | |
529 | * @rb: rb-tree node | |
530 | * @lnum: LEB number | |
531 | */ | |
532 | struct done_ref { | |
533 | struct rb_node rb; | |
534 | int lnum; | |
535 | }; | |
536 | ||
537 | /** | |
538 | * done_already - determine if a reference has been done already. | |
539 | * @done_tree: rb-tree to store references that have been done | |
540 | * @lnum: LEB number of reference | |
541 | * | |
542 | * This function returns %1 if the reference has been done, %0 if not, otherwise | |
543 | * a negative error code is returned. | |
544 | */ | |
545 | static int done_already(struct rb_root *done_tree, int lnum) | |
546 | { | |
547 | struct rb_node **p = &done_tree->rb_node, *parent = NULL; | |
548 | struct done_ref *dr; | |
549 | ||
550 | while (*p) { | |
551 | parent = *p; | |
552 | dr = rb_entry(parent, struct done_ref, rb); | |
553 | if (lnum < dr->lnum) | |
554 | p = &(*p)->rb_left; | |
555 | else if (lnum > dr->lnum) | |
556 | p = &(*p)->rb_right; | |
557 | else | |
558 | return 1; | |
559 | } | |
560 | ||
561 | dr = kzalloc(sizeof(struct done_ref), GFP_NOFS); | |
562 | if (!dr) | |
563 | return -ENOMEM; | |
564 | ||
565 | dr->lnum = lnum; | |
566 | ||
567 | rb_link_node(&dr->rb, parent, p); | |
568 | rb_insert_color(&dr->rb, done_tree); | |
569 | ||
570 | return 0; | |
571 | } | |
572 | ||
573 | /** | |
574 | * destroy_done_tree - destroy the done tree. | |
575 | * @done_tree: done tree to destroy | |
576 | */ | |
577 | static void destroy_done_tree(struct rb_root *done_tree) | |
578 | { | |
579 | struct rb_node *this = done_tree->rb_node; | |
580 | struct done_ref *dr; | |
581 | ||
582 | while (this) { | |
583 | if (this->rb_left) { | |
584 | this = this->rb_left; | |
585 | continue; | |
586 | } else if (this->rb_right) { | |
587 | this = this->rb_right; | |
588 | continue; | |
589 | } | |
590 | dr = rb_entry(this, struct done_ref, rb); | |
591 | this = rb_parent(this); | |
592 | if (this) { | |
593 | if (this->rb_left == &dr->rb) | |
594 | this->rb_left = NULL; | |
595 | else | |
596 | this->rb_right = NULL; | |
597 | } | |
598 | kfree(dr); | |
599 | } | |
600 | } | |
601 | ||
602 | /** | |
603 | * add_node - add a node to the consolidated log. | |
604 | * @c: UBIFS file-system description object | |
605 | * @buf: buffer to which to add | |
606 | * @lnum: LEB number to which to write is passed and returned here | |
607 | * @offs: offset to where to write is passed and returned here | |
608 | * @node: node to add | |
609 | * | |
610 | * This function returns %0 on success and a negative error code on failure. | |
611 | */ | |
612 | static int add_node(struct ubifs_info *c, void *buf, int *lnum, int *offs, | |
613 | void *node) | |
614 | { | |
615 | struct ubifs_ch *ch = node; | |
616 | int len = le32_to_cpu(ch->len), remains = c->leb_size - *offs; | |
617 | ||
618 | if (len > remains) { | |
619 | int sz = ALIGN(*offs, c->min_io_size), err; | |
620 | ||
621 | ubifs_pad(c, buf + *offs, sz - *offs); | |
b36a261e | 622 | err = ubifs_leb_change(c, *lnum, buf, sz); |
1e51764a AB |
623 | if (err) |
624 | return err; | |
e11602ea | 625 | *lnum = ubifs_next_log_lnum(c, *lnum); |
1e51764a AB |
626 | *offs = 0; |
627 | } | |
628 | memcpy(buf + *offs, node, len); | |
629 | *offs += ALIGN(len, 8); | |
630 | return 0; | |
631 | } | |
632 | ||
633 | /** | |
634 | * ubifs_consolidate_log - consolidate the log. | |
635 | * @c: UBIFS file-system description object | |
636 | * | |
637 | * Repeated failed commits could cause the log to be full, but at least 1 LEB is | |
638 | * needed for commit. This function rewrites the reference nodes in the log | |
639 | * omitting duplicates, and failed CS nodes, and leaving no gaps. | |
640 | * | |
641 | * This function returns %0 on success and a negative error code on failure. | |
642 | */ | |
643 | int ubifs_consolidate_log(struct ubifs_info *c) | |
644 | { | |
645 | struct ubifs_scan_leb *sleb; | |
646 | struct ubifs_scan_node *snod; | |
647 | struct rb_root done_tree = RB_ROOT; | |
648 | int lnum, err, first = 1, write_lnum, offs = 0; | |
649 | void *buf; | |
650 | ||
651 | dbg_rcvry("log tail LEB %d, log head LEB %d", c->ltail_lnum, | |
652 | c->lhead_lnum); | |
653 | buf = vmalloc(c->leb_size); | |
654 | if (!buf) | |
655 | return -ENOMEM; | |
656 | lnum = c->ltail_lnum; | |
657 | write_lnum = lnum; | |
658 | while (1) { | |
348709ba | 659 | sleb = ubifs_scan(c, lnum, 0, c->sbuf, 0); |
1e51764a AB |
660 | if (IS_ERR(sleb)) { |
661 | err = PTR_ERR(sleb); | |
662 | goto out_free; | |
663 | } | |
664 | list_for_each_entry(snod, &sleb->nodes, list) { | |
665 | switch (snod->type) { | |
666 | case UBIFS_REF_NODE: { | |
667 | struct ubifs_ref_node *ref = snod->node; | |
668 | int ref_lnum = le32_to_cpu(ref->lnum); | |
669 | ||
670 | err = done_already(&done_tree, ref_lnum); | |
671 | if (err < 0) | |
672 | goto out_scan; | |
673 | if (err != 1) { | |
674 | err = add_node(c, buf, &write_lnum, | |
675 | &offs, snod->node); | |
676 | if (err) | |
677 | goto out_scan; | |
678 | } | |
679 | break; | |
680 | } | |
681 | case UBIFS_CS_NODE: | |
682 | if (!first) | |
683 | break; | |
684 | err = add_node(c, buf, &write_lnum, &offs, | |
685 | snod->node); | |
686 | if (err) | |
687 | goto out_scan; | |
688 | first = 0; | |
689 | break; | |
690 | } | |
691 | } | |
692 | ubifs_scan_destroy(sleb); | |
693 | if (lnum == c->lhead_lnum) | |
694 | break; | |
e11602ea | 695 | lnum = ubifs_next_log_lnum(c, lnum); |
1e51764a AB |
696 | } |
697 | if (offs) { | |
698 | int sz = ALIGN(offs, c->min_io_size); | |
699 | ||
700 | ubifs_pad(c, buf + offs, sz - offs); | |
b36a261e | 701 | err = ubifs_leb_change(c, write_lnum, buf, sz); |
1e51764a AB |
702 | if (err) |
703 | goto out_free; | |
704 | offs = ALIGN(offs, c->min_io_size); | |
705 | } | |
706 | destroy_done_tree(&done_tree); | |
707 | vfree(buf); | |
708 | if (write_lnum == c->lhead_lnum) { | |
709 | ubifs_err("log is too full"); | |
710 | return -EINVAL; | |
711 | } | |
712 | /* Unmap remaining LEBs */ | |
713 | lnum = write_lnum; | |
714 | do { | |
e11602ea | 715 | lnum = ubifs_next_log_lnum(c, lnum); |
1e51764a AB |
716 | err = ubifs_leb_unmap(c, lnum); |
717 | if (err) | |
718 | return err; | |
719 | } while (lnum != c->lhead_lnum); | |
720 | c->lhead_lnum = write_lnum; | |
721 | c->lhead_offs = offs; | |
722 | dbg_rcvry("new log head at %d:%d", c->lhead_lnum, c->lhead_offs); | |
723 | return 0; | |
724 | ||
725 | out_scan: | |
726 | ubifs_scan_destroy(sleb); | |
727 | out_free: | |
728 | destroy_done_tree(&done_tree); | |
729 | vfree(buf); | |
730 | return err; | |
731 | } | |
732 | ||
1e51764a AB |
733 | /** |
734 | * dbg_check_bud_bytes - make sure bud bytes calculation are all right. | |
735 | * @c: UBIFS file-system description object | |
736 | * | |
737 | * This function makes sure the amount of flash space used by closed buds | |
738 | * ('c->bud_bytes' is correct). Returns zero in case of success and %-EINVAL in | |
739 | * case of failure. | |
740 | */ | |
741 | static int dbg_check_bud_bytes(struct ubifs_info *c) | |
742 | { | |
743 | int i, err = 0; | |
744 | struct ubifs_bud *bud; | |
745 | long long bud_bytes = 0; | |
746 | ||
2b1844a8 | 747 | if (!dbg_is_chk_gen(c)) |
1e51764a AB |
748 | return 0; |
749 | ||
750 | spin_lock(&c->buds_lock); | |
751 | for (i = 0; i < c->jhead_cnt; i++) | |
752 | list_for_each_entry(bud, &c->jheads[i].buds_list, list) | |
753 | bud_bytes += c->leb_size - bud->start; | |
754 | ||
755 | if (c->bud_bytes != bud_bytes) { | |
756 | ubifs_err("bad bud_bytes %lld, calculated %lld", | |
757 | c->bud_bytes, bud_bytes); | |
758 | err = -EINVAL; | |
759 | } | |
760 | spin_unlock(&c->buds_lock); | |
761 | ||
762 | return err; | |
763 | } |