Commit | Line | Data |
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470decc6 | 1 | /* |
58862699 | 2 | * linux/fs/jbd2/recovery.c |
470decc6 DK |
3 | * |
4 | * Written by Stephen C. Tweedie <sct@redhat.com>, 1999 | |
5 | * | |
6 | * Copyright 1999-2000 Red Hat Software --- All Rights Reserved | |
7 | * | |
8 | * This file is part of the Linux kernel and is made available under | |
9 | * the terms of the GNU General Public License, version 2, or at your | |
10 | * option, any later version, incorporated herein by reference. | |
11 | * | |
12 | * Journal recovery routines for the generic filesystem journaling code; | |
13 | * part of the ext2fs journaling system. | |
14 | */ | |
15 | ||
16 | #ifndef __KERNEL__ | |
17 | #include "jfs_user.h" | |
18 | #else | |
19 | #include <linux/time.h> | |
20 | #include <linux/fs.h> | |
f7f4bccb | 21 | #include <linux/jbd2.h> |
470decc6 | 22 | #include <linux/errno.h> |
818d276c | 23 | #include <linux/crc32.h> |
470decc6 DK |
24 | #endif |
25 | ||
26 | /* | |
27 | * Maintain information about the progress of the recovery job, so that | |
28 | * the different passes can carry information between them. | |
29 | */ | |
30 | struct recovery_info | |
31 | { | |
32 | tid_t start_transaction; | |
33 | tid_t end_transaction; | |
34 | ||
35 | int nr_replays; | |
36 | int nr_revokes; | |
37 | int nr_revoke_hits; | |
38 | }; | |
39 | ||
40 | enum passtype {PASS_SCAN, PASS_REVOKE, PASS_REPLAY}; | |
41 | static int do_one_pass(journal_t *journal, | |
42 | struct recovery_info *info, enum passtype pass); | |
43 | static int scan_revoke_records(journal_t *, struct buffer_head *, | |
44 | tid_t, struct recovery_info *); | |
45 | ||
46 | #ifdef __KERNEL__ | |
47 | ||
48 | /* Release readahead buffers after use */ | |
49 | static void journal_brelse_array(struct buffer_head *b[], int n) | |
50 | { | |
51 | while (--n >= 0) | |
52 | brelse (b[n]); | |
53 | } | |
54 | ||
55 | ||
56 | /* | |
57 | * When reading from the journal, we are going through the block device | |
58 | * layer directly and so there is no readahead being done for us. We | |
59 | * need to implement any readahead ourselves if we want it to happen at | |
60 | * all. Recovery is basically one long sequential read, so make sure we | |
61 | * do the IO in reasonably large chunks. | |
62 | * | |
63 | * This is not so critical that we need to be enormously clever about | |
64 | * the readahead size, though. 128K is a purely arbitrary, good-enough | |
65 | * fixed value. | |
66 | */ | |
67 | ||
68 | #define MAXBUF 8 | |
69 | static int do_readahead(journal_t *journal, unsigned int start) | |
70 | { | |
71 | int err; | |
72 | unsigned int max, nbufs, next; | |
18eba7aa | 73 | unsigned long long blocknr; |
470decc6 DK |
74 | struct buffer_head *bh; |
75 | ||
76 | struct buffer_head * bufs[MAXBUF]; | |
77 | ||
78 | /* Do up to 128K of readahead */ | |
79 | max = start + (128 * 1024 / journal->j_blocksize); | |
80 | if (max > journal->j_maxlen) | |
81 | max = journal->j_maxlen; | |
82 | ||
83 | /* Do the readahead itself. We'll submit MAXBUF buffer_heads at | |
84 | * a time to the block device IO layer. */ | |
85 | ||
86 | nbufs = 0; | |
87 | ||
88 | for (next = start; next < max; next++) { | |
f7f4bccb | 89 | err = jbd2_journal_bmap(journal, next, &blocknr); |
470decc6 DK |
90 | |
91 | if (err) { | |
92 | printk (KERN_ERR "JBD: bad block at offset %u\n", | |
93 | next); | |
94 | goto failed; | |
95 | } | |
96 | ||
97 | bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize); | |
98 | if (!bh) { | |
99 | err = -ENOMEM; | |
100 | goto failed; | |
101 | } | |
102 | ||
103 | if (!buffer_uptodate(bh) && !buffer_locked(bh)) { | |
104 | bufs[nbufs++] = bh; | |
105 | if (nbufs == MAXBUF) { | |
106 | ll_rw_block(READ, nbufs, bufs); | |
107 | journal_brelse_array(bufs, nbufs); | |
108 | nbufs = 0; | |
109 | } | |
110 | } else | |
111 | brelse(bh); | |
112 | } | |
113 | ||
114 | if (nbufs) | |
115 | ll_rw_block(READ, nbufs, bufs); | |
116 | err = 0; | |
117 | ||
118 | failed: | |
119 | if (nbufs) | |
120 | journal_brelse_array(bufs, nbufs); | |
121 | return err; | |
122 | } | |
123 | ||
124 | #endif /* __KERNEL__ */ | |
125 | ||
126 | ||
127 | /* | |
128 | * Read a block from the journal | |
129 | */ | |
130 | ||
131 | static int jread(struct buffer_head **bhp, journal_t *journal, | |
132 | unsigned int offset) | |
133 | { | |
134 | int err; | |
18eba7aa | 135 | unsigned long long blocknr; |
470decc6 DK |
136 | struct buffer_head *bh; |
137 | ||
138 | *bhp = NULL; | |
139 | ||
140 | if (offset >= journal->j_maxlen) { | |
141 | printk(KERN_ERR "JBD: corrupted journal superblock\n"); | |
142 | return -EIO; | |
143 | } | |
144 | ||
f7f4bccb | 145 | err = jbd2_journal_bmap(journal, offset, &blocknr); |
470decc6 DK |
146 | |
147 | if (err) { | |
148 | printk (KERN_ERR "JBD: bad block at offset %u\n", | |
149 | offset); | |
150 | return err; | |
151 | } | |
152 | ||
153 | bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize); | |
154 | if (!bh) | |
155 | return -ENOMEM; | |
156 | ||
157 | if (!buffer_uptodate(bh)) { | |
158 | /* If this is a brand new buffer, start readahead. | |
159 | Otherwise, we assume we are already reading it. */ | |
160 | if (!buffer_req(bh)) | |
161 | do_readahead(journal, offset); | |
162 | wait_on_buffer(bh); | |
163 | } | |
164 | ||
165 | if (!buffer_uptodate(bh)) { | |
166 | printk (KERN_ERR "JBD: Failed to read block at offset %u\n", | |
167 | offset); | |
168 | brelse(bh); | |
169 | return -EIO; | |
170 | } | |
171 | ||
172 | *bhp = bh; | |
173 | return 0; | |
174 | } | |
175 | ||
176 | ||
177 | /* | |
178 | * Count the number of in-use tags in a journal descriptor block. | |
179 | */ | |
180 | ||
b517bea1 | 181 | static int count_tags(journal_t *journal, struct buffer_head *bh) |
470decc6 DK |
182 | { |
183 | char * tagp; | |
184 | journal_block_tag_t * tag; | |
b517bea1 ZB |
185 | int nr = 0, size = journal->j_blocksize; |
186 | int tag_bytes = journal_tag_bytes(journal); | |
470decc6 DK |
187 | |
188 | tagp = &bh->b_data[sizeof(journal_header_t)]; | |
189 | ||
b517bea1 | 190 | while ((tagp - bh->b_data + tag_bytes) <= size) { |
470decc6 DK |
191 | tag = (journal_block_tag_t *) tagp; |
192 | ||
193 | nr++; | |
b517bea1 | 194 | tagp += tag_bytes; |
f7f4bccb | 195 | if (!(tag->t_flags & cpu_to_be32(JBD2_FLAG_SAME_UUID))) |
470decc6 DK |
196 | tagp += 16; |
197 | ||
f7f4bccb | 198 | if (tag->t_flags & cpu_to_be32(JBD2_FLAG_LAST_TAG)) |
470decc6 DK |
199 | break; |
200 | } | |
201 | ||
202 | return nr; | |
203 | } | |
204 | ||
205 | ||
206 | /* Make sure we wrap around the log correctly! */ | |
207 | #define wrap(journal, var) \ | |
208 | do { \ | |
209 | if (var >= (journal)->j_last) \ | |
210 | var -= ((journal)->j_last - (journal)->j_first); \ | |
211 | } while (0) | |
212 | ||
213 | /** | |
f7f4bccb | 214 | * jbd2_journal_recover - recovers a on-disk journal |
470decc6 DK |
215 | * @journal: the journal to recover |
216 | * | |
217 | * The primary function for recovering the log contents when mounting a | |
218 | * journaled device. | |
219 | * | |
220 | * Recovery is done in three passes. In the first pass, we look for the | |
221 | * end of the log. In the second, we assemble the list of revoke | |
222 | * blocks. In the third and final pass, we replay any un-revoked blocks | |
223 | * in the log. | |
224 | */ | |
f7f4bccb | 225 | int jbd2_journal_recover(journal_t *journal) |
470decc6 | 226 | { |
44519faf | 227 | int err, err2; |
470decc6 DK |
228 | journal_superblock_t * sb; |
229 | ||
230 | struct recovery_info info; | |
231 | ||
232 | memset(&info, 0, sizeof(info)); | |
233 | sb = journal->j_superblock; | |
234 | ||
235 | /* | |
236 | * The journal superblock's s_start field (the current log head) | |
237 | * is always zero if, and only if, the journal was cleanly | |
238 | * unmounted. | |
239 | */ | |
240 | ||
241 | if (!sb->s_start) { | |
242 | jbd_debug(1, "No recovery required, last transaction %d\n", | |
243 | be32_to_cpu(sb->s_sequence)); | |
244 | journal->j_transaction_sequence = be32_to_cpu(sb->s_sequence) + 1; | |
245 | return 0; | |
246 | } | |
247 | ||
248 | err = do_one_pass(journal, &info, PASS_SCAN); | |
249 | if (!err) | |
250 | err = do_one_pass(journal, &info, PASS_REVOKE); | |
251 | if (!err) | |
252 | err = do_one_pass(journal, &info, PASS_REPLAY); | |
253 | ||
b38bd33a | 254 | jbd_debug(1, "JBD: recovery, exit status %d, " |
470decc6 DK |
255 | "recovered transactions %u to %u\n", |
256 | err, info.start_transaction, info.end_transaction); | |
b38bd33a | 257 | jbd_debug(1, "JBD: Replayed %d and revoked %d/%d blocks\n", |
470decc6 DK |
258 | info.nr_replays, info.nr_revoke_hits, info.nr_revokes); |
259 | ||
260 | /* Restart the log at the next transaction ID, thus invalidating | |
261 | * any existing commit records in the log. */ | |
262 | journal->j_transaction_sequence = ++info.end_transaction; | |
263 | ||
f7f4bccb | 264 | jbd2_journal_clear_revoke(journal); |
44519faf HK |
265 | err2 = sync_blockdev(journal->j_fs_dev); |
266 | if (!err) | |
267 | err = err2; | |
268 | ||
470decc6 DK |
269 | return err; |
270 | } | |
271 | ||
272 | /** | |
f7f4bccb | 273 | * jbd2_journal_skip_recovery - Start journal and wipe exiting records |
470decc6 DK |
274 | * @journal: journal to startup |
275 | * | |
276 | * Locate any valid recovery information from the journal and set up the | |
277 | * journal structures in memory to ignore it (presumably because the | |
278 | * caller has evidence that it is out of date). | |
279 | * This function does'nt appear to be exorted.. | |
280 | * | |
281 | * We perform one pass over the journal to allow us to tell the user how | |
282 | * much recovery information is being erased, and to let us initialise | |
283 | * the journal transaction sequence numbers to the next unused ID. | |
284 | */ | |
f7f4bccb | 285 | int jbd2_journal_skip_recovery(journal_t *journal) |
470decc6 DK |
286 | { |
287 | int err; | |
288 | journal_superblock_t * sb; | |
289 | ||
290 | struct recovery_info info; | |
291 | ||
292 | memset (&info, 0, sizeof(info)); | |
293 | sb = journal->j_superblock; | |
294 | ||
295 | err = do_one_pass(journal, &info, PASS_SCAN); | |
296 | ||
297 | if (err) { | |
298 | printk(KERN_ERR "JBD: error %d scanning journal\n", err); | |
299 | ++journal->j_transaction_sequence; | |
300 | } else { | |
e23291b9 | 301 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 DK |
302 | int dropped = info.end_transaction - be32_to_cpu(sb->s_sequence); |
303 | #endif | |
b38bd33a | 304 | jbd_debug(1, |
470decc6 DK |
305 | "JBD: ignoring %d transaction%s from the journal.\n", |
306 | dropped, (dropped == 1) ? "" : "s"); | |
307 | journal->j_transaction_sequence = ++info.end_transaction; | |
308 | } | |
309 | ||
310 | journal->j_tail = 0; | |
311 | return err; | |
312 | } | |
313 | ||
18eba7aa | 314 | static inline unsigned long long read_tag_block(int tag_bytes, journal_block_tag_t *tag) |
b517bea1 | 315 | { |
18eba7aa | 316 | unsigned long long block = be32_to_cpu(tag->t_blocknr); |
cd02ff0b | 317 | if (tag_bytes > JBD2_TAG_SIZE32) |
b517bea1 ZB |
318 | block |= (u64)be32_to_cpu(tag->t_blocknr_high) << 32; |
319 | return block; | |
320 | } | |
321 | ||
818d276c GS |
322 | /* |
323 | * calc_chksums calculates the checksums for the blocks described in the | |
324 | * descriptor block. | |
325 | */ | |
326 | static int calc_chksums(journal_t *journal, struct buffer_head *bh, | |
327 | unsigned long *next_log_block, __u32 *crc32_sum) | |
328 | { | |
329 | int i, num_blks, err; | |
330 | unsigned long io_block; | |
331 | struct buffer_head *obh; | |
332 | ||
333 | num_blks = count_tags(journal, bh); | |
334 | /* Calculate checksum of the descriptor block. */ | |
335 | *crc32_sum = crc32_be(*crc32_sum, (void *)bh->b_data, bh->b_size); | |
336 | ||
337 | for (i = 0; i < num_blks; i++) { | |
338 | io_block = (*next_log_block)++; | |
339 | wrap(journal, *next_log_block); | |
340 | err = jread(&obh, journal, io_block); | |
341 | if (err) { | |
342 | printk(KERN_ERR "JBD: IO error %d recovering block " | |
343 | "%lu in log\n", err, io_block); | |
344 | return 1; | |
345 | } else { | |
346 | *crc32_sum = crc32_be(*crc32_sum, (void *)obh->b_data, | |
347 | obh->b_size); | |
348 | } | |
8ea76900 | 349 | put_bh(obh); |
818d276c GS |
350 | } |
351 | return 0; | |
352 | } | |
353 | ||
470decc6 DK |
354 | static int do_one_pass(journal_t *journal, |
355 | struct recovery_info *info, enum passtype pass) | |
356 | { | |
357 | unsigned int first_commit_ID, next_commit_ID; | |
358 | unsigned long next_log_block; | |
359 | int err, success = 0; | |
360 | journal_superblock_t * sb; | |
361 | journal_header_t * tmp; | |
362 | struct buffer_head * bh; | |
363 | unsigned int sequence; | |
364 | int blocktype; | |
b517bea1 | 365 | int tag_bytes = journal_tag_bytes(journal); |
818d276c | 366 | __u32 crc32_sum = ~0; /* Transactional Checksums */ |
470decc6 DK |
367 | |
368 | /* Precompute the maximum metadata descriptors in a descriptor block */ | |
369 | int MAX_BLOCKS_PER_DESC; | |
370 | MAX_BLOCKS_PER_DESC = ((journal->j_blocksize-sizeof(journal_header_t)) | |
b517bea1 | 371 | / tag_bytes); |
470decc6 DK |
372 | |
373 | /* | |
374 | * First thing is to establish what we expect to find in the log | |
375 | * (in terms of transaction IDs), and where (in terms of log | |
376 | * block offsets): query the superblock. | |
377 | */ | |
378 | ||
379 | sb = journal->j_superblock; | |
380 | next_commit_ID = be32_to_cpu(sb->s_sequence); | |
381 | next_log_block = be32_to_cpu(sb->s_start); | |
382 | ||
383 | first_commit_ID = next_commit_ID; | |
384 | if (pass == PASS_SCAN) | |
385 | info->start_transaction = first_commit_ID; | |
386 | ||
387 | jbd_debug(1, "Starting recovery pass %d\n", pass); | |
388 | ||
389 | /* | |
390 | * Now we walk through the log, transaction by transaction, | |
391 | * making sure that each transaction has a commit block in the | |
392 | * expected place. Each complete transaction gets replayed back | |
393 | * into the main filesystem. | |
394 | */ | |
395 | ||
396 | while (1) { | |
397 | int flags; | |
398 | char * tagp; | |
399 | journal_block_tag_t * tag; | |
400 | struct buffer_head * obh; | |
401 | struct buffer_head * nbh; | |
402 | ||
e86e1438 | 403 | cond_resched(); |
470decc6 DK |
404 | |
405 | /* If we already know where to stop the log traversal, | |
406 | * check right now that we haven't gone past the end of | |
407 | * the log. */ | |
408 | ||
409 | if (pass != PASS_SCAN) | |
410 | if (tid_geq(next_commit_ID, info->end_transaction)) | |
411 | break; | |
412 | ||
413 | jbd_debug(2, "Scanning for sequence ID %u at %lu/%lu\n", | |
414 | next_commit_ID, next_log_block, journal->j_last); | |
415 | ||
416 | /* Skip over each chunk of the transaction looking | |
417 | * either the next descriptor block or the final commit | |
418 | * record. */ | |
419 | ||
420 | jbd_debug(3, "JBD: checking block %ld\n", next_log_block); | |
421 | err = jread(&bh, journal, next_log_block); | |
422 | if (err) | |
423 | goto failed; | |
424 | ||
425 | next_log_block++; | |
426 | wrap(journal, next_log_block); | |
427 | ||
428 | /* What kind of buffer is it? | |
429 | * | |
430 | * If it is a descriptor block, check that it has the | |
431 | * expected sequence number. Otherwise, we're all done | |
432 | * here. */ | |
433 | ||
434 | tmp = (journal_header_t *)bh->b_data; | |
435 | ||
f7f4bccb | 436 | if (tmp->h_magic != cpu_to_be32(JBD2_MAGIC_NUMBER)) { |
470decc6 DK |
437 | brelse(bh); |
438 | break; | |
439 | } | |
440 | ||
441 | blocktype = be32_to_cpu(tmp->h_blocktype); | |
442 | sequence = be32_to_cpu(tmp->h_sequence); | |
443 | jbd_debug(3, "Found magic %d, sequence %d\n", | |
444 | blocktype, sequence); | |
445 | ||
446 | if (sequence != next_commit_ID) { | |
447 | brelse(bh); | |
448 | break; | |
449 | } | |
450 | ||
451 | /* OK, we have a valid descriptor block which matches | |
452 | * all of the sequence number checks. What are we going | |
453 | * to do with it? That depends on the pass... */ | |
454 | ||
455 | switch(blocktype) { | |
f7f4bccb | 456 | case JBD2_DESCRIPTOR_BLOCK: |
470decc6 | 457 | /* If it is a valid descriptor block, replay it |
818d276c GS |
458 | * in pass REPLAY; if journal_checksums enabled, then |
459 | * calculate checksums in PASS_SCAN, otherwise, | |
460 | * just skip over the blocks it describes. */ | |
470decc6 | 461 | if (pass != PASS_REPLAY) { |
818d276c GS |
462 | if (pass == PASS_SCAN && |
463 | JBD2_HAS_COMPAT_FEATURE(journal, | |
464 | JBD2_FEATURE_COMPAT_CHECKSUM) && | |
465 | !info->end_transaction) { | |
466 | if (calc_chksums(journal, bh, | |
467 | &next_log_block, | |
468 | &crc32_sum)) { | |
469 | put_bh(bh); | |
470 | break; | |
471 | } | |
472 | put_bh(bh); | |
473 | continue; | |
474 | } | |
b517bea1 | 475 | next_log_block += count_tags(journal, bh); |
470decc6 | 476 | wrap(journal, next_log_block); |
818d276c | 477 | put_bh(bh); |
470decc6 DK |
478 | continue; |
479 | } | |
480 | ||
481 | /* A descriptor block: we can now write all of | |
482 | * the data blocks. Yay, useful work is finally | |
483 | * getting done here! */ | |
484 | ||
485 | tagp = &bh->b_data[sizeof(journal_header_t)]; | |
b517bea1 | 486 | while ((tagp - bh->b_data + tag_bytes) |
470decc6 DK |
487 | <= journal->j_blocksize) { |
488 | unsigned long io_block; | |
489 | ||
490 | tag = (journal_block_tag_t *) tagp; | |
491 | flags = be32_to_cpu(tag->t_flags); | |
492 | ||
493 | io_block = next_log_block++; | |
494 | wrap(journal, next_log_block); | |
495 | err = jread(&obh, journal, io_block); | |
496 | if (err) { | |
497 | /* Recover what we can, but | |
498 | * report failure at the end. */ | |
499 | success = err; | |
500 | printk (KERN_ERR | |
501 | "JBD: IO error %d recovering " | |
502 | "block %ld in log\n", | |
503 | err, io_block); | |
504 | } else { | |
18eba7aa | 505 | unsigned long long blocknr; |
470decc6 DK |
506 | |
507 | J_ASSERT(obh != NULL); | |
b517bea1 ZB |
508 | blocknr = read_tag_block(tag_bytes, |
509 | tag); | |
470decc6 DK |
510 | |
511 | /* If the block has been | |
512 | * revoked, then we're all done | |
513 | * here. */ | |
f7f4bccb | 514 | if (jbd2_journal_test_revoke |
470decc6 DK |
515 | (journal, blocknr, |
516 | next_commit_ID)) { | |
517 | brelse(obh); | |
518 | ++info->nr_revoke_hits; | |
519 | goto skip_write; | |
520 | } | |
521 | ||
522 | /* Find a buffer for the new | |
523 | * data being restored */ | |
524 | nbh = __getblk(journal->j_fs_dev, | |
525 | blocknr, | |
526 | journal->j_blocksize); | |
527 | if (nbh == NULL) { | |
528 | printk(KERN_ERR | |
529 | "JBD: Out of memory " | |
530 | "during recovery.\n"); | |
531 | err = -ENOMEM; | |
532 | brelse(bh); | |
533 | brelse(obh); | |
534 | goto failed; | |
535 | } | |
536 | ||
537 | lock_buffer(nbh); | |
538 | memcpy(nbh->b_data, obh->b_data, | |
539 | journal->j_blocksize); | |
f7f4bccb | 540 | if (flags & JBD2_FLAG_ESCAPE) { |
d0025676 | 541 | *((__be32 *)nbh->b_data) = |
f7f4bccb | 542 | cpu_to_be32(JBD2_MAGIC_NUMBER); |
470decc6 DK |
543 | } |
544 | ||
545 | BUFFER_TRACE(nbh, "marking dirty"); | |
546 | set_buffer_uptodate(nbh); | |
547 | mark_buffer_dirty(nbh); | |
548 | BUFFER_TRACE(nbh, "marking uptodate"); | |
549 | ++info->nr_replays; | |
550 | /* ll_rw_block(WRITE, 1, &nbh); */ | |
551 | unlock_buffer(nbh); | |
552 | brelse(obh); | |
553 | brelse(nbh); | |
554 | } | |
555 | ||
556 | skip_write: | |
b517bea1 | 557 | tagp += tag_bytes; |
f7f4bccb | 558 | if (!(flags & JBD2_FLAG_SAME_UUID)) |
470decc6 DK |
559 | tagp += 16; |
560 | ||
f7f4bccb | 561 | if (flags & JBD2_FLAG_LAST_TAG) |
470decc6 DK |
562 | break; |
563 | } | |
564 | ||
565 | brelse(bh); | |
566 | continue; | |
567 | ||
f7f4bccb | 568 | case JBD2_COMMIT_BLOCK: |
818d276c GS |
569 | /* How to differentiate between interrupted commit |
570 | * and journal corruption ? | |
571 | * | |
572 | * {nth transaction} | |
573 | * Checksum Verification Failed | |
574 | * | | |
575 | * ____________________ | |
576 | * | | | |
577 | * async_commit sync_commit | |
578 | * | | | |
579 | * | GO TO NEXT "Journal Corruption" | |
580 | * | TRANSACTION | |
581 | * | | |
582 | * {(n+1)th transanction} | |
583 | * | | |
584 | * _______|______________ | |
585 | * | | | |
586 | * Commit block found Commit block not found | |
587 | * | | | |
588 | * "Journal Corruption" | | |
589 | * _____________|_________ | |
590 | * | | | |
591 | * nth trans corrupt OR nth trans | |
592 | * and (n+1)th interrupted interrupted | |
593 | * before commit block | |
594 | * could reach the disk. | |
595 | * (Cannot find the difference in above | |
596 | * mentioned conditions. Hence assume | |
597 | * "Interrupted Commit".) | |
598 | */ | |
599 | ||
600 | /* Found an expected commit block: if checksums | |
601 | * are present verify them in PASS_SCAN; else not | |
602 | * much to do other than move on to the next sequence | |
470decc6 | 603 | * number. */ |
818d276c GS |
604 | if (pass == PASS_SCAN && |
605 | JBD2_HAS_COMPAT_FEATURE(journal, | |
606 | JBD2_FEATURE_COMPAT_CHECKSUM)) { | |
607 | int chksum_err, chksum_seen; | |
608 | struct commit_header *cbh = | |
609 | (struct commit_header *)bh->b_data; | |
610 | unsigned found_chksum = | |
611 | be32_to_cpu(cbh->h_chksum[0]); | |
612 | ||
613 | chksum_err = chksum_seen = 0; | |
614 | ||
615 | if (info->end_transaction) { | |
624080ed TT |
616 | journal->j_failed_commit = |
617 | info->end_transaction; | |
818d276c GS |
618 | brelse(bh); |
619 | break; | |
620 | } | |
621 | ||
622 | if (crc32_sum == found_chksum && | |
623 | cbh->h_chksum_type == JBD2_CRC32_CHKSUM && | |
624 | cbh->h_chksum_size == | |
625 | JBD2_CRC32_CHKSUM_SIZE) | |
626 | chksum_seen = 1; | |
627 | else if (!(cbh->h_chksum_type == 0 && | |
628 | cbh->h_chksum_size == 0 && | |
629 | found_chksum == 0 && | |
630 | !chksum_seen)) | |
631 | /* | |
632 | * If fs is mounted using an old kernel and then | |
633 | * kernel with journal_chksum is used then we | |
634 | * get a situation where the journal flag has | |
635 | * checksum flag set but checksums are not | |
636 | * present i.e chksum = 0, in the individual | |
637 | * commit blocks. | |
638 | * Hence to avoid checksum failures, in this | |
639 | * situation, this extra check is added. | |
640 | */ | |
641 | chksum_err = 1; | |
642 | ||
643 | if (chksum_err) { | |
644 | info->end_transaction = next_commit_ID; | |
645 | ||
4d605179 | 646 | if (!JBD2_HAS_INCOMPAT_FEATURE(journal, |
818d276c | 647 | JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT)){ |
624080ed TT |
648 | journal->j_failed_commit = |
649 | next_commit_ID; | |
818d276c GS |
650 | brelse(bh); |
651 | break; | |
652 | } | |
653 | } | |
654 | crc32_sum = ~0; | |
655 | } | |
470decc6 DK |
656 | brelse(bh); |
657 | next_commit_ID++; | |
658 | continue; | |
659 | ||
f7f4bccb | 660 | case JBD2_REVOKE_BLOCK: |
470decc6 DK |
661 | /* If we aren't in the REVOKE pass, then we can |
662 | * just skip over this block. */ | |
663 | if (pass != PASS_REVOKE) { | |
664 | brelse(bh); | |
665 | continue; | |
666 | } | |
667 | ||
668 | err = scan_revoke_records(journal, bh, | |
669 | next_commit_ID, info); | |
670 | brelse(bh); | |
671 | if (err) | |
672 | goto failed; | |
673 | continue; | |
674 | ||
675 | default: | |
676 | jbd_debug(3, "Unrecognised magic %d, end of scan.\n", | |
677 | blocktype); | |
678 | brelse(bh); | |
679 | goto done; | |
680 | } | |
681 | } | |
682 | ||
683 | done: | |
684 | /* | |
685 | * We broke out of the log scan loop: either we came to the | |
686 | * known end of the log or we found an unexpected block in the | |
687 | * log. If the latter happened, then we know that the "current" | |
688 | * transaction marks the end of the valid log. | |
689 | */ | |
690 | ||
818d276c GS |
691 | if (pass == PASS_SCAN) { |
692 | if (!info->end_transaction) | |
693 | info->end_transaction = next_commit_ID; | |
694 | } else { | |
470decc6 DK |
695 | /* It's really bad news if different passes end up at |
696 | * different places (but possible due to IO errors). */ | |
697 | if (info->end_transaction != next_commit_ID) { | |
698 | printk (KERN_ERR "JBD: recovery pass %d ended at " | |
699 | "transaction %u, expected %u\n", | |
700 | pass, next_commit_ID, info->end_transaction); | |
701 | if (!success) | |
702 | success = -EIO; | |
703 | } | |
704 | } | |
705 | ||
706 | return success; | |
707 | ||
708 | failed: | |
709 | return err; | |
710 | } | |
711 | ||
712 | ||
713 | /* Scan a revoke record, marking all blocks mentioned as revoked. */ | |
714 | ||
715 | static int scan_revoke_records(journal_t *journal, struct buffer_head *bh, | |
716 | tid_t sequence, struct recovery_info *info) | |
717 | { | |
f7f4bccb | 718 | jbd2_journal_revoke_header_t *header; |
470decc6 | 719 | int offset, max; |
b517bea1 | 720 | int record_len = 4; |
470decc6 | 721 | |
f7f4bccb MC |
722 | header = (jbd2_journal_revoke_header_t *) bh->b_data; |
723 | offset = sizeof(jbd2_journal_revoke_header_t); | |
470decc6 DK |
724 | max = be32_to_cpu(header->r_count); |
725 | ||
b517bea1 ZB |
726 | if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_64BIT)) |
727 | record_len = 8; | |
728 | ||
729 | while (offset + record_len <= max) { | |
18eba7aa | 730 | unsigned long long blocknr; |
470decc6 DK |
731 | int err; |
732 | ||
b517bea1 ZB |
733 | if (record_len == 4) |
734 | blocknr = be32_to_cpu(* ((__be32 *) (bh->b_data+offset))); | |
735 | else | |
736 | blocknr = be64_to_cpu(* ((__be64 *) (bh->b_data+offset))); | |
737 | offset += record_len; | |
f7f4bccb | 738 | err = jbd2_journal_set_revoke(journal, blocknr, sequence); |
470decc6 DK |
739 | if (err) |
740 | return err; | |
741 | ++info->nr_revokes; | |
742 | } | |
743 | return 0; | |
744 | } |