]>
Commit | Line | Data |
---|---|---|
0f3e1c7f RK |
1 | /* |
2 | * recovery.c - NILFS recovery logic | |
3 | * | |
4 | * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License as published by | |
8 | * the Free Software Foundation; either version 2 of the License, or | |
9 | * (at your option) any later version. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, write to the Free Software | |
18 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
19 | * | |
20 | * Written by Ryusuke Konishi <ryusuke@osrg.net> | |
21 | */ | |
22 | ||
23 | #include <linux/buffer_head.h> | |
24 | #include <linux/blkdev.h> | |
25 | #include <linux/swap.h> | |
26 | #include <linux/crc32.h> | |
27 | #include "nilfs.h" | |
28 | #include "segment.h" | |
29 | #include "sufile.h" | |
30 | #include "page.h" | |
31 | #include "seglist.h" | |
32 | #include "segbuf.h" | |
33 | ||
34 | /* | |
35 | * Segment check result | |
36 | */ | |
37 | enum { | |
38 | NILFS_SEG_VALID, | |
39 | NILFS_SEG_NO_SUPER_ROOT, | |
40 | NILFS_SEG_FAIL_IO, | |
41 | NILFS_SEG_FAIL_MAGIC, | |
42 | NILFS_SEG_FAIL_SEQ, | |
43 | NILFS_SEG_FAIL_CHECKSUM_SEGSUM, | |
44 | NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT, | |
45 | NILFS_SEG_FAIL_CHECKSUM_FULL, | |
46 | NILFS_SEG_FAIL_CONSISTENCY, | |
47 | }; | |
48 | ||
49 | /* work structure for recovery */ | |
50 | struct nilfs_recovery_block { | |
51 | ino_t ino; /* Inode number of the file that this block | |
52 | belongs to */ | |
53 | sector_t blocknr; /* block number */ | |
54 | __u64 vblocknr; /* virtual block number */ | |
55 | unsigned long blkoff; /* File offset of the data block (per block) */ | |
56 | struct list_head list; | |
57 | }; | |
58 | ||
59 | ||
60 | static int nilfs_warn_segment_error(int err) | |
61 | { | |
62 | switch (err) { | |
63 | case NILFS_SEG_FAIL_IO: | |
64 | printk(KERN_WARNING | |
65 | "NILFS warning: I/O error on loading last segment\n"); | |
66 | return -EIO; | |
67 | case NILFS_SEG_FAIL_MAGIC: | |
68 | printk(KERN_WARNING | |
69 | "NILFS warning: Segment magic number invalid\n"); | |
70 | break; | |
71 | case NILFS_SEG_FAIL_SEQ: | |
72 | printk(KERN_WARNING | |
73 | "NILFS warning: Sequence number mismatch\n"); | |
74 | break; | |
75 | case NILFS_SEG_FAIL_CHECKSUM_SEGSUM: | |
76 | printk(KERN_WARNING | |
77 | "NILFS warning: Checksum error in segment summary\n"); | |
78 | break; | |
79 | case NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT: | |
80 | printk(KERN_WARNING | |
81 | "NILFS warning: Checksum error in super root\n"); | |
82 | break; | |
83 | case NILFS_SEG_FAIL_CHECKSUM_FULL: | |
84 | printk(KERN_WARNING | |
85 | "NILFS warning: Checksum error in segment payload\n"); | |
86 | break; | |
87 | case NILFS_SEG_FAIL_CONSISTENCY: | |
88 | printk(KERN_WARNING | |
89 | "NILFS warning: Inconsistent segment\n"); | |
90 | break; | |
91 | case NILFS_SEG_NO_SUPER_ROOT: | |
92 | printk(KERN_WARNING | |
93 | "NILFS warning: No super root in the last segment\n"); | |
94 | break; | |
0f3e1c7f RK |
95 | } |
96 | return -EINVAL; | |
97 | } | |
98 | ||
99 | static void store_segsum_info(struct nilfs_segsum_info *ssi, | |
100 | struct nilfs_segment_summary *sum, | |
101 | unsigned int blocksize) | |
102 | { | |
103 | ssi->flags = le16_to_cpu(sum->ss_flags); | |
104 | ssi->seg_seq = le64_to_cpu(sum->ss_seq); | |
105 | ssi->ctime = le64_to_cpu(sum->ss_create); | |
106 | ssi->next = le64_to_cpu(sum->ss_next); | |
107 | ssi->nblocks = le32_to_cpu(sum->ss_nblocks); | |
108 | ssi->nfinfo = le32_to_cpu(sum->ss_nfinfo); | |
109 | ssi->sumbytes = le32_to_cpu(sum->ss_sumbytes); | |
110 | ||
111 | ssi->nsumblk = DIV_ROUND_UP(ssi->sumbytes, blocksize); | |
112 | ssi->nfileblk = ssi->nblocks - ssi->nsumblk - !!NILFS_SEG_HAS_SR(ssi); | |
113 | } | |
114 | ||
115 | /** | |
116 | * calc_crc_cont - check CRC of blocks continuously | |
117 | * @sbi: nilfs_sb_info | |
118 | * @bhs: buffer head of start block | |
119 | * @sum: place to store result | |
120 | * @offset: offset bytes in the first block | |
121 | * @check_bytes: number of bytes to be checked | |
122 | * @start: DBN of start block | |
123 | * @nblock: number of blocks to be checked | |
124 | */ | |
125 | static int calc_crc_cont(struct nilfs_sb_info *sbi, struct buffer_head *bhs, | |
126 | u32 *sum, unsigned long offset, u64 check_bytes, | |
127 | sector_t start, unsigned long nblock) | |
128 | { | |
129 | unsigned long blocksize = sbi->s_super->s_blocksize; | |
130 | unsigned long size; | |
131 | u32 crc; | |
132 | ||
133 | BUG_ON(offset >= blocksize); | |
134 | check_bytes -= offset; | |
135 | size = min_t(u64, check_bytes, blocksize - offset); | |
136 | crc = crc32_le(sbi->s_nilfs->ns_crc_seed, | |
137 | (unsigned char *)bhs->b_data + offset, size); | |
138 | if (--nblock > 0) { | |
139 | do { | |
140 | struct buffer_head *bh | |
141 | = sb_bread(sbi->s_super, ++start); | |
142 | if (!bh) | |
143 | return -EIO; | |
144 | check_bytes -= size; | |
145 | size = min_t(u64, check_bytes, blocksize); | |
146 | crc = crc32_le(crc, bh->b_data, size); | |
147 | brelse(bh); | |
148 | } while (--nblock > 0); | |
149 | } | |
150 | *sum = crc; | |
151 | return 0; | |
152 | } | |
153 | ||
154 | /** | |
155 | * nilfs_read_super_root_block - read super root block | |
156 | * @sb: super_block | |
157 | * @sr_block: disk block number of the super root block | |
158 | * @pbh: address of a buffer_head pointer to return super root buffer | |
159 | * @check: CRC check flag | |
160 | */ | |
161 | int nilfs_read_super_root_block(struct super_block *sb, sector_t sr_block, | |
162 | struct buffer_head **pbh, int check) | |
163 | { | |
164 | struct buffer_head *bh_sr; | |
165 | struct nilfs_super_root *sr; | |
166 | u32 crc; | |
167 | int ret; | |
168 | ||
169 | *pbh = NULL; | |
170 | bh_sr = sb_bread(sb, sr_block); | |
171 | if (unlikely(!bh_sr)) { | |
172 | ret = NILFS_SEG_FAIL_IO; | |
173 | goto failed; | |
174 | } | |
175 | ||
176 | sr = (struct nilfs_super_root *)bh_sr->b_data; | |
177 | if (check) { | |
178 | unsigned bytes = le16_to_cpu(sr->sr_bytes); | |
179 | ||
180 | if (bytes == 0 || bytes > sb->s_blocksize) { | |
181 | ret = NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT; | |
182 | goto failed_bh; | |
183 | } | |
184 | if (calc_crc_cont(NILFS_SB(sb), bh_sr, &crc, | |
185 | sizeof(sr->sr_sum), bytes, sr_block, 1)) { | |
186 | ret = NILFS_SEG_FAIL_IO; | |
187 | goto failed_bh; | |
188 | } | |
189 | if (crc != le32_to_cpu(sr->sr_sum)) { | |
190 | ret = NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT; | |
191 | goto failed_bh; | |
192 | } | |
193 | } | |
194 | *pbh = bh_sr; | |
195 | return 0; | |
196 | ||
197 | failed_bh: | |
198 | brelse(bh_sr); | |
199 | ||
200 | failed: | |
201 | return nilfs_warn_segment_error(ret); | |
202 | } | |
203 | ||
204 | /** | |
205 | * load_segment_summary - read segment summary of the specified partial segment | |
206 | * @sbi: nilfs_sb_info | |
207 | * @pseg_start: start disk block number of partial segment | |
208 | * @seg_seq: sequence number requested | |
209 | * @ssi: pointer to nilfs_segsum_info struct to store information | |
210 | * @full_check: full check flag | |
211 | * (0: only checks segment summary CRC, 1: data CRC) | |
212 | */ | |
213 | static int | |
214 | load_segment_summary(struct nilfs_sb_info *sbi, sector_t pseg_start, | |
215 | u64 seg_seq, struct nilfs_segsum_info *ssi, | |
216 | int full_check) | |
217 | { | |
218 | struct buffer_head *bh_sum; | |
219 | struct nilfs_segment_summary *sum; | |
220 | unsigned long offset, nblock; | |
221 | u64 check_bytes; | |
222 | u32 crc, crc_sum; | |
223 | int ret = NILFS_SEG_FAIL_IO; | |
224 | ||
225 | bh_sum = sb_bread(sbi->s_super, pseg_start); | |
226 | if (!bh_sum) | |
227 | goto out; | |
228 | ||
229 | sum = (struct nilfs_segment_summary *)bh_sum->b_data; | |
230 | ||
231 | /* Check consistency of segment summary */ | |
232 | if (le32_to_cpu(sum->ss_magic) != NILFS_SEGSUM_MAGIC) { | |
233 | ret = NILFS_SEG_FAIL_MAGIC; | |
234 | goto failed; | |
235 | } | |
236 | store_segsum_info(ssi, sum, sbi->s_super->s_blocksize); | |
237 | if (seg_seq != ssi->seg_seq) { | |
238 | ret = NILFS_SEG_FAIL_SEQ; | |
239 | goto failed; | |
240 | } | |
241 | if (full_check) { | |
242 | offset = sizeof(sum->ss_datasum); | |
243 | check_bytes = | |
244 | ((u64)ssi->nblocks << sbi->s_super->s_blocksize_bits); | |
245 | nblock = ssi->nblocks; | |
246 | crc_sum = le32_to_cpu(sum->ss_datasum); | |
247 | ret = NILFS_SEG_FAIL_CHECKSUM_FULL; | |
248 | } else { /* only checks segment summary */ | |
249 | offset = sizeof(sum->ss_datasum) + sizeof(sum->ss_sumsum); | |
250 | check_bytes = ssi->sumbytes; | |
251 | nblock = ssi->nsumblk; | |
252 | crc_sum = le32_to_cpu(sum->ss_sumsum); | |
253 | ret = NILFS_SEG_FAIL_CHECKSUM_SEGSUM; | |
254 | } | |
255 | ||
256 | if (unlikely(nblock == 0 || | |
257 | nblock > sbi->s_nilfs->ns_blocks_per_segment)) { | |
258 | /* This limits the number of blocks read in the CRC check */ | |
259 | ret = NILFS_SEG_FAIL_CONSISTENCY; | |
260 | goto failed; | |
261 | } | |
262 | if (calc_crc_cont(sbi, bh_sum, &crc, offset, check_bytes, | |
263 | pseg_start, nblock)) { | |
264 | ret = NILFS_SEG_FAIL_IO; | |
265 | goto failed; | |
266 | } | |
267 | if (crc == crc_sum) | |
268 | ret = 0; | |
269 | failed: | |
270 | brelse(bh_sum); | |
271 | out: | |
272 | return ret; | |
273 | } | |
274 | ||
275 | static void *segsum_get(struct super_block *sb, struct buffer_head **pbh, | |
276 | unsigned int *offset, unsigned int bytes) | |
277 | { | |
278 | void *ptr; | |
279 | sector_t blocknr; | |
280 | ||
281 | BUG_ON((*pbh)->b_size < *offset); | |
282 | if (bytes > (*pbh)->b_size - *offset) { | |
283 | blocknr = (*pbh)->b_blocknr; | |
284 | brelse(*pbh); | |
285 | *pbh = sb_bread(sb, blocknr + 1); | |
286 | if (unlikely(!*pbh)) | |
287 | return NULL; | |
288 | *offset = 0; | |
289 | } | |
290 | ptr = (*pbh)->b_data + *offset; | |
291 | *offset += bytes; | |
292 | return ptr; | |
293 | } | |
294 | ||
295 | static void segsum_skip(struct super_block *sb, struct buffer_head **pbh, | |
296 | unsigned int *offset, unsigned int bytes, | |
297 | unsigned long count) | |
298 | { | |
299 | unsigned int rest_item_in_current_block | |
300 | = ((*pbh)->b_size - *offset) / bytes; | |
301 | ||
302 | if (count <= rest_item_in_current_block) { | |
303 | *offset += bytes * count; | |
304 | } else { | |
305 | sector_t blocknr = (*pbh)->b_blocknr; | |
306 | unsigned int nitem_per_block = (*pbh)->b_size / bytes; | |
307 | unsigned int bcnt; | |
308 | ||
309 | count -= rest_item_in_current_block; | |
310 | bcnt = DIV_ROUND_UP(count, nitem_per_block); | |
311 | *offset = bytes * (count - (bcnt - 1) * nitem_per_block); | |
312 | ||
313 | brelse(*pbh); | |
314 | *pbh = sb_bread(sb, blocknr + bcnt); | |
315 | } | |
316 | } | |
317 | ||
318 | static int | |
319 | collect_blocks_from_segsum(struct nilfs_sb_info *sbi, sector_t sum_blocknr, | |
320 | struct nilfs_segsum_info *ssi, | |
321 | struct list_head *head) | |
322 | { | |
323 | struct buffer_head *bh; | |
324 | unsigned int offset; | |
325 | unsigned long nfinfo = ssi->nfinfo; | |
326 | sector_t blocknr = sum_blocknr + ssi->nsumblk; | |
327 | ino_t ino; | |
328 | int err = -EIO; | |
329 | ||
330 | if (!nfinfo) | |
331 | return 0; | |
332 | ||
333 | bh = sb_bread(sbi->s_super, sum_blocknr); | |
334 | if (unlikely(!bh)) | |
335 | goto out; | |
336 | ||
337 | offset = le16_to_cpu( | |
338 | ((struct nilfs_segment_summary *)bh->b_data)->ss_bytes); | |
339 | for (;;) { | |
340 | unsigned long nblocks, ndatablk, nnodeblk; | |
341 | struct nilfs_finfo *finfo; | |
342 | ||
343 | finfo = segsum_get(sbi->s_super, &bh, &offset, sizeof(*finfo)); | |
344 | if (unlikely(!finfo)) | |
345 | goto out; | |
346 | ||
347 | ino = le64_to_cpu(finfo->fi_ino); | |
348 | nblocks = le32_to_cpu(finfo->fi_nblocks); | |
349 | ndatablk = le32_to_cpu(finfo->fi_ndatablk); | |
350 | nnodeblk = nblocks - ndatablk; | |
351 | ||
352 | while (ndatablk-- > 0) { | |
353 | struct nilfs_recovery_block *rb; | |
354 | struct nilfs_binfo_v *binfo; | |
355 | ||
356 | binfo = segsum_get(sbi->s_super, &bh, &offset, | |
357 | sizeof(*binfo)); | |
358 | if (unlikely(!binfo)) | |
359 | goto out; | |
360 | ||
361 | rb = kmalloc(sizeof(*rb), GFP_NOFS); | |
362 | if (unlikely(!rb)) { | |
363 | err = -ENOMEM; | |
364 | goto out; | |
365 | } | |
366 | rb->ino = ino; | |
367 | rb->blocknr = blocknr++; | |
368 | rb->vblocknr = le64_to_cpu(binfo->bi_vblocknr); | |
369 | rb->blkoff = le64_to_cpu(binfo->bi_blkoff); | |
370 | /* INIT_LIST_HEAD(&rb->list); */ | |
371 | list_add_tail(&rb->list, head); | |
372 | } | |
373 | if (--nfinfo == 0) | |
374 | break; | |
375 | blocknr += nnodeblk; /* always 0 for the data sync segments */ | |
376 | segsum_skip(sbi->s_super, &bh, &offset, sizeof(__le64), | |
377 | nnodeblk); | |
378 | if (unlikely(!bh)) | |
379 | goto out; | |
380 | } | |
381 | err = 0; | |
382 | out: | |
383 | brelse(bh); /* brelse(NULL) is just ignored */ | |
384 | return err; | |
385 | } | |
386 | ||
387 | static void dispose_recovery_list(struct list_head *head) | |
388 | { | |
389 | while (!list_empty(head)) { | |
390 | struct nilfs_recovery_block *rb | |
391 | = list_entry(head->next, | |
392 | struct nilfs_recovery_block, list); | |
393 | list_del(&rb->list); | |
394 | kfree(rb); | |
395 | } | |
396 | } | |
397 | ||
398 | void nilfs_dispose_segment_list(struct list_head *head) | |
399 | { | |
400 | while (!list_empty(head)) { | |
401 | struct nilfs_segment_entry *ent | |
402 | = list_entry(head->next, | |
403 | struct nilfs_segment_entry, list); | |
404 | list_del(&ent->list); | |
405 | nilfs_free_segment_entry(ent); | |
406 | } | |
407 | } | |
408 | ||
409 | static int nilfs_prepare_segment_for_recovery(struct the_nilfs *nilfs, | |
85c2a74f | 410 | struct nilfs_sb_info *sbi, |
0f3e1c7f RK |
411 | struct nilfs_recovery_info *ri) |
412 | { | |
413 | struct list_head *head = &ri->ri_used_segments; | |
414 | struct nilfs_segment_entry *ent, *n; | |
415 | struct inode *sufile = nilfs->ns_sufile; | |
416 | __u64 segnum[4]; | |
417 | int err; | |
418 | int i; | |
419 | ||
420 | segnum[0] = nilfs->ns_segnum; | |
421 | segnum[1] = nilfs->ns_nextnum; | |
422 | segnum[2] = ri->ri_segnum; | |
423 | segnum[3] = ri->ri_nextnum; | |
424 | ||
85c2a74f | 425 | nilfs_attach_writer(nilfs, sbi); |
0f3e1c7f RK |
426 | /* |
427 | * Releasing the next segment of the latest super root. | |
428 | * The next segment is invalidated by this recovery. | |
429 | */ | |
430 | err = nilfs_sufile_free(sufile, segnum[1]); | |
431 | if (unlikely(err)) | |
432 | goto failed; | |
433 | ||
434 | err = -ENOMEM; | |
435 | for (i = 1; i < 4; i++) { | |
436 | ent = nilfs_alloc_segment_entry(segnum[i]); | |
437 | if (unlikely(!ent)) | |
438 | goto failed; | |
439 | list_add_tail(&ent->list, head); | |
440 | } | |
441 | ||
442 | /* | |
443 | * Collecting segments written after the latest super root. | |
2c2e52fc | 444 | * These are marked dirty to avoid being reallocated in the next write. |
0f3e1c7f RK |
445 | */ |
446 | list_for_each_entry_safe(ent, n, head, list) { | |
c85399c2 RK |
447 | if (ent->segnum != segnum[0]) { |
448 | err = nilfs_sufile_scrap(sufile, ent->segnum); | |
449 | if (unlikely(err)) | |
450 | goto failed; | |
0f3e1c7f | 451 | } |
2c2e52fc | 452 | list_del(&ent->list); |
2c2e52fc | 453 | nilfs_free_segment_entry(ent); |
0f3e1c7f | 454 | } |
0f3e1c7f | 455 | |
0f3e1c7f RK |
456 | /* Allocate new segments for recovery */ |
457 | err = nilfs_sufile_alloc(sufile, &segnum[0]); | |
458 | if (unlikely(err)) | |
459 | goto failed; | |
460 | ||
461 | nilfs->ns_pseg_offset = 0; | |
462 | nilfs->ns_seg_seq = ri->ri_seq + 2; | |
463 | nilfs->ns_nextnum = nilfs->ns_segnum = segnum[0]; | |
0f3e1c7f RK |
464 | |
465 | failed: | |
466 | /* No need to recover sufile because it will be destroyed on error */ | |
85c2a74f | 467 | nilfs_detach_writer(nilfs, sbi); |
0f3e1c7f RK |
468 | return err; |
469 | } | |
470 | ||
471 | static int nilfs_recovery_copy_block(struct nilfs_sb_info *sbi, | |
472 | struct nilfs_recovery_block *rb, | |
473 | struct page *page) | |
474 | { | |
475 | struct buffer_head *bh_org; | |
476 | void *kaddr; | |
477 | ||
478 | bh_org = sb_bread(sbi->s_super, rb->blocknr); | |
479 | if (unlikely(!bh_org)) | |
480 | return -EIO; | |
481 | ||
482 | kaddr = kmap_atomic(page, KM_USER0); | |
483 | memcpy(kaddr + bh_offset(bh_org), bh_org->b_data, bh_org->b_size); | |
484 | kunmap_atomic(kaddr, KM_USER0); | |
485 | brelse(bh_org); | |
486 | return 0; | |
487 | } | |
488 | ||
489 | static int recover_dsync_blocks(struct nilfs_sb_info *sbi, | |
490 | struct list_head *head, | |
491 | unsigned long *nr_salvaged_blocks) | |
492 | { | |
493 | struct inode *inode; | |
494 | struct nilfs_recovery_block *rb, *n; | |
495 | unsigned blocksize = sbi->s_super->s_blocksize; | |
496 | struct page *page; | |
497 | loff_t pos; | |
498 | int err = 0, err2 = 0; | |
499 | ||
500 | list_for_each_entry_safe(rb, n, head, list) { | |
501 | inode = nilfs_iget(sbi->s_super, rb->ino); | |
502 | if (IS_ERR(inode)) { | |
503 | err = PTR_ERR(inode); | |
504 | inode = NULL; | |
505 | goto failed_inode; | |
506 | } | |
507 | ||
508 | pos = rb->blkoff << inode->i_blkbits; | |
509 | page = NULL; | |
510 | err = block_write_begin(NULL, inode->i_mapping, pos, blocksize, | |
511 | 0, &page, NULL, nilfs_get_block); | |
512 | if (unlikely(err)) | |
513 | goto failed_inode; | |
514 | ||
515 | err = nilfs_recovery_copy_block(sbi, rb, page); | |
516 | if (unlikely(err)) | |
517 | goto failed_page; | |
518 | ||
519 | err = nilfs_set_file_dirty(sbi, inode, 1); | |
520 | if (unlikely(err)) | |
521 | goto failed_page; | |
522 | ||
523 | block_write_end(NULL, inode->i_mapping, pos, blocksize, | |
524 | blocksize, page, NULL); | |
525 | ||
526 | unlock_page(page); | |
527 | page_cache_release(page); | |
528 | ||
529 | (*nr_salvaged_blocks)++; | |
530 | goto next; | |
531 | ||
532 | failed_page: | |
533 | unlock_page(page); | |
534 | page_cache_release(page); | |
535 | ||
536 | failed_inode: | |
537 | printk(KERN_WARNING | |
538 | "NILFS warning: error recovering data block " | |
539 | "(err=%d, ino=%lu, block-offset=%llu)\n", | |
540 | err, rb->ino, (unsigned long long)rb->blkoff); | |
541 | if (!err2) | |
542 | err2 = err; | |
543 | next: | |
544 | iput(inode); /* iput(NULL) is just ignored */ | |
545 | list_del_init(&rb->list); | |
546 | kfree(rb); | |
547 | } | |
548 | return err2; | |
549 | } | |
550 | ||
551 | /** | |
552 | * nilfs_do_roll_forward - salvage logical segments newer than the latest | |
553 | * checkpoint | |
554 | * @sbi: nilfs_sb_info | |
555 | * @nilfs: the_nilfs | |
556 | * @ri: pointer to a nilfs_recovery_info | |
557 | */ | |
558 | static int nilfs_do_roll_forward(struct the_nilfs *nilfs, | |
559 | struct nilfs_sb_info *sbi, | |
560 | struct nilfs_recovery_info *ri) | |
561 | { | |
562 | struct nilfs_segsum_info ssi; | |
563 | sector_t pseg_start; | |
564 | sector_t seg_start, seg_end; /* Starting/ending DBN of full segment */ | |
565 | unsigned long nsalvaged_blocks = 0; | |
566 | u64 seg_seq; | |
567 | __u64 segnum, nextnum = 0; | |
568 | int empty_seg = 0; | |
569 | int err = 0, ret; | |
570 | LIST_HEAD(dsync_blocks); /* list of data blocks to be recovered */ | |
571 | enum { | |
572 | RF_INIT_ST, | |
573 | RF_DSYNC_ST, /* scanning data-sync segments */ | |
574 | }; | |
575 | int state = RF_INIT_ST; | |
576 | ||
577 | nilfs_attach_writer(nilfs, sbi); | |
578 | pseg_start = ri->ri_lsegs_start; | |
579 | seg_seq = ri->ri_lsegs_start_seq; | |
580 | segnum = nilfs_get_segnum_of_block(nilfs, pseg_start); | |
581 | nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); | |
582 | ||
583 | while (segnum != ri->ri_segnum || pseg_start <= ri->ri_pseg_start) { | |
584 | ||
585 | ret = load_segment_summary(sbi, pseg_start, seg_seq, &ssi, 1); | |
586 | if (ret) { | |
587 | if (ret == NILFS_SEG_FAIL_IO) { | |
588 | err = -EIO; | |
589 | goto failed; | |
590 | } | |
591 | goto strayed; | |
592 | } | |
593 | if (unlikely(NILFS_SEG_HAS_SR(&ssi))) | |
594 | goto confused; | |
595 | ||
596 | /* Found a valid partial segment; do recovery actions */ | |
597 | nextnum = nilfs_get_segnum_of_block(nilfs, ssi.next); | |
598 | empty_seg = 0; | |
599 | nilfs->ns_ctime = ssi.ctime; | |
600 | if (!(ssi.flags & NILFS_SS_GC)) | |
601 | nilfs->ns_nongc_ctime = ssi.ctime; | |
602 | ||
603 | switch (state) { | |
604 | case RF_INIT_ST: | |
605 | if (!NILFS_SEG_LOGBGN(&ssi) || !NILFS_SEG_DSYNC(&ssi)) | |
606 | goto try_next_pseg; | |
607 | state = RF_DSYNC_ST; | |
608 | /* Fall through */ | |
609 | case RF_DSYNC_ST: | |
610 | if (!NILFS_SEG_DSYNC(&ssi)) | |
611 | goto confused; | |
612 | ||
613 | err = collect_blocks_from_segsum( | |
614 | sbi, pseg_start, &ssi, &dsync_blocks); | |
615 | if (unlikely(err)) | |
616 | goto failed; | |
617 | if (NILFS_SEG_LOGEND(&ssi)) { | |
618 | err = recover_dsync_blocks( | |
619 | sbi, &dsync_blocks, &nsalvaged_blocks); | |
620 | if (unlikely(err)) | |
621 | goto failed; | |
622 | state = RF_INIT_ST; | |
623 | } | |
624 | break; /* Fall through to try_next_pseg */ | |
625 | } | |
626 | ||
627 | try_next_pseg: | |
628 | if (pseg_start == ri->ri_lsegs_end) | |
629 | break; | |
630 | pseg_start += ssi.nblocks; | |
631 | if (pseg_start < seg_end) | |
632 | continue; | |
633 | goto feed_segment; | |
634 | ||
635 | strayed: | |
636 | if (pseg_start == ri->ri_lsegs_end) | |
637 | break; | |
638 | ||
639 | feed_segment: | |
640 | /* Looking to the next full segment */ | |
641 | if (empty_seg++) | |
642 | break; | |
643 | seg_seq++; | |
644 | segnum = nextnum; | |
645 | nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); | |
646 | pseg_start = seg_start; | |
647 | } | |
648 | ||
649 | if (nsalvaged_blocks) { | |
650 | printk(KERN_INFO "NILFS (device %s): salvaged %lu blocks\n", | |
651 | sbi->s_super->s_id, nsalvaged_blocks); | |
652 | ri->ri_need_recovery = NILFS_RECOVERY_ROLLFORWARD_DONE; | |
653 | } | |
654 | out: | |
655 | dispose_recovery_list(&dsync_blocks); | |
656 | nilfs_detach_writer(sbi->s_nilfs, sbi); | |
657 | return err; | |
658 | ||
659 | confused: | |
660 | err = -EINVAL; | |
661 | failed: | |
662 | printk(KERN_ERR | |
663 | "NILFS (device %s): Error roll-forwarding " | |
664 | "(err=%d, pseg block=%llu). ", | |
665 | sbi->s_super->s_id, err, (unsigned long long)pseg_start); | |
666 | goto out; | |
667 | } | |
668 | ||
669 | static void nilfs_finish_roll_forward(struct the_nilfs *nilfs, | |
670 | struct nilfs_sb_info *sbi, | |
671 | struct nilfs_recovery_info *ri) | |
672 | { | |
673 | struct buffer_head *bh; | |
674 | int err; | |
675 | ||
676 | if (nilfs_get_segnum_of_block(nilfs, ri->ri_lsegs_start) != | |
677 | nilfs_get_segnum_of_block(nilfs, ri->ri_super_root)) | |
678 | return; | |
679 | ||
680 | bh = sb_getblk(sbi->s_super, ri->ri_lsegs_start); | |
681 | BUG_ON(!bh); | |
682 | memset(bh->b_data, 0, bh->b_size); | |
683 | set_buffer_dirty(bh); | |
684 | err = sync_dirty_buffer(bh); | |
685 | if (unlikely(err)) | |
686 | printk(KERN_WARNING | |
687 | "NILFS warning: buffer sync write failed during " | |
688 | "post-cleaning of recovery.\n"); | |
689 | brelse(bh); | |
690 | } | |
691 | ||
692 | /** | |
693 | * nilfs_recover_logical_segments - salvage logical segments written after | |
694 | * the latest super root | |
695 | * @nilfs: the_nilfs | |
696 | * @sbi: nilfs_sb_info | |
697 | * @ri: pointer to a nilfs_recovery_info struct to store search results. | |
698 | * | |
699 | * Return Value: On success, 0 is returned. On error, one of the following | |
700 | * negative error code is returned. | |
701 | * | |
702 | * %-EINVAL - Inconsistent filesystem state. | |
703 | * | |
704 | * %-EIO - I/O error | |
705 | * | |
706 | * %-ENOSPC - No space left on device (only in a panic state). | |
707 | * | |
708 | * %-ERESTARTSYS - Interrupted. | |
709 | * | |
710 | * %-ENOMEM - Insufficient memory available. | |
711 | */ | |
712 | int nilfs_recover_logical_segments(struct the_nilfs *nilfs, | |
713 | struct nilfs_sb_info *sbi, | |
714 | struct nilfs_recovery_info *ri) | |
715 | { | |
716 | int err; | |
717 | ||
718 | if (ri->ri_lsegs_start == 0 || ri->ri_lsegs_end == 0) | |
719 | return 0; | |
720 | ||
721 | err = nilfs_attach_checkpoint(sbi, ri->ri_cno); | |
722 | if (unlikely(err)) { | |
723 | printk(KERN_ERR | |
724 | "NILFS: error loading the latest checkpoint.\n"); | |
725 | return err; | |
726 | } | |
727 | ||
728 | err = nilfs_do_roll_forward(nilfs, sbi, ri); | |
729 | if (unlikely(err)) | |
730 | goto failed; | |
731 | ||
732 | if (ri->ri_need_recovery == NILFS_RECOVERY_ROLLFORWARD_DONE) { | |
85c2a74f | 733 | err = nilfs_prepare_segment_for_recovery(nilfs, sbi, ri); |
0f3e1c7f RK |
734 | if (unlikely(err)) { |
735 | printk(KERN_ERR "NILFS: Error preparing segments for " | |
736 | "recovery.\n"); | |
737 | goto failed; | |
738 | } | |
739 | ||
cece5520 | 740 | err = nilfs_attach_segment_constructor(sbi); |
0f3e1c7f RK |
741 | if (unlikely(err)) |
742 | goto failed; | |
743 | ||
744 | set_nilfs_discontinued(nilfs); | |
745 | err = nilfs_construct_segment(sbi->s_super); | |
746 | nilfs_detach_segment_constructor(sbi); | |
747 | ||
748 | if (unlikely(err)) { | |
749 | printk(KERN_ERR "NILFS: Oops! recovery failed. " | |
750 | "(err=%d)\n", err); | |
751 | goto failed; | |
752 | } | |
753 | ||
754 | nilfs_finish_roll_forward(nilfs, sbi, ri); | |
755 | } | |
756 | ||
757 | nilfs_detach_checkpoint(sbi); | |
758 | return 0; | |
759 | ||
760 | failed: | |
761 | nilfs_detach_checkpoint(sbi); | |
762 | nilfs_mdt_clear(nilfs->ns_cpfile); | |
763 | nilfs_mdt_clear(nilfs->ns_sufile); | |
764 | nilfs_mdt_clear(nilfs->ns_dat); | |
765 | return err; | |
766 | } | |
767 | ||
768 | /** | |
769 | * nilfs_search_super_root - search the latest valid super root | |
770 | * @nilfs: the_nilfs | |
771 | * @sbi: nilfs_sb_info | |
772 | * @ri: pointer to a nilfs_recovery_info struct to store search results. | |
773 | * | |
774 | * nilfs_search_super_root() looks for the latest super-root from a partial | |
775 | * segment pointed by the superblock. It sets up struct the_nilfs through | |
776 | * this search. It fills nilfs_recovery_info (ri) required for recovery. | |
777 | * | |
778 | * Return Value: On success, 0 is returned. On error, one of the following | |
779 | * negative error code is returned. | |
780 | * | |
781 | * %-EINVAL - No valid segment found | |
782 | * | |
783 | * %-EIO - I/O error | |
784 | */ | |
785 | int nilfs_search_super_root(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi, | |
786 | struct nilfs_recovery_info *ri) | |
787 | { | |
788 | struct nilfs_segsum_info ssi; | |
789 | sector_t pseg_start, pseg_end, sr_pseg_start = 0; | |
790 | sector_t seg_start, seg_end; /* range of full segment (block number) */ | |
791 | u64 seg_seq; | |
792 | __u64 segnum, nextnum = 0; | |
793 | __u64 cno; | |
794 | struct nilfs_segment_entry *ent; | |
795 | LIST_HEAD(segments); | |
796 | int empty_seg = 0, scan_newer = 0; | |
797 | int ret; | |
798 | ||
799 | pseg_start = nilfs->ns_last_pseg; | |
800 | seg_seq = nilfs->ns_last_seq; | |
801 | cno = nilfs->ns_last_cno; | |
802 | segnum = nilfs_get_segnum_of_block(nilfs, pseg_start); | |
803 | ||
804 | /* Calculate range of segment */ | |
805 | nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); | |
806 | ||
807 | for (;;) { | |
808 | /* Load segment summary */ | |
809 | ret = load_segment_summary(sbi, pseg_start, seg_seq, &ssi, 1); | |
810 | if (ret) { | |
811 | if (ret == NILFS_SEG_FAIL_IO) | |
812 | goto failed; | |
813 | goto strayed; | |
814 | } | |
815 | pseg_end = pseg_start + ssi.nblocks - 1; | |
816 | if (unlikely(pseg_end > seg_end)) { | |
817 | ret = NILFS_SEG_FAIL_CONSISTENCY; | |
818 | goto strayed; | |
819 | } | |
820 | ||
821 | /* A valid partial segment */ | |
822 | ri->ri_pseg_start = pseg_start; | |
823 | ri->ri_seq = seg_seq; | |
824 | ri->ri_segnum = segnum; | |
825 | nextnum = nilfs_get_segnum_of_block(nilfs, ssi.next); | |
826 | ri->ri_nextnum = nextnum; | |
827 | empty_seg = 0; | |
828 | ||
829 | if (!NILFS_SEG_HAS_SR(&ssi)) { | |
830 | if (!scan_newer) { | |
831 | /* This will never happen because a superblock | |
832 | (last_segment) always points to a pseg | |
833 | having a super root. */ | |
834 | ret = NILFS_SEG_FAIL_CONSISTENCY; | |
835 | goto failed; | |
836 | } | |
837 | if (!ri->ri_lsegs_start && NILFS_SEG_LOGBGN(&ssi)) { | |
838 | ri->ri_lsegs_start = pseg_start; | |
839 | ri->ri_lsegs_start_seq = seg_seq; | |
840 | } | |
841 | if (NILFS_SEG_LOGEND(&ssi)) | |
842 | ri->ri_lsegs_end = pseg_start; | |
843 | goto try_next_pseg; | |
844 | } | |
845 | ||
846 | /* A valid super root was found. */ | |
847 | ri->ri_cno = cno++; | |
848 | ri->ri_super_root = pseg_end; | |
849 | ri->ri_lsegs_start = ri->ri_lsegs_end = 0; | |
850 | ||
851 | nilfs_dispose_segment_list(&segments); | |
852 | nilfs->ns_pseg_offset = (sr_pseg_start = pseg_start) | |
853 | + ssi.nblocks - seg_start; | |
854 | nilfs->ns_seg_seq = seg_seq; | |
855 | nilfs->ns_segnum = segnum; | |
856 | nilfs->ns_cno = cno; /* nilfs->ns_cno = ri->ri_cno + 1 */ | |
857 | nilfs->ns_ctime = ssi.ctime; | |
858 | nilfs->ns_nextnum = nextnum; | |
859 | ||
860 | if (scan_newer) | |
861 | ri->ri_need_recovery = NILFS_RECOVERY_SR_UPDATED; | |
2c2e52fc | 862 | else { |
2c2e52fc RK |
863 | if (nilfs->ns_mount_state & NILFS_VALID_FS) |
864 | goto super_root_found; | |
865 | scan_newer = 1; | |
866 | } | |
0f3e1c7f RK |
867 | |
868 | /* reset region for roll-forward */ | |
869 | pseg_start += ssi.nblocks; | |
870 | if (pseg_start < seg_end) | |
871 | continue; | |
872 | goto feed_segment; | |
873 | ||
874 | try_next_pseg: | |
875 | /* Standing on a course, or met an inconsistent state */ | |
876 | pseg_start += ssi.nblocks; | |
877 | if (pseg_start < seg_end) | |
878 | continue; | |
879 | goto feed_segment; | |
880 | ||
881 | strayed: | |
882 | /* Off the trail */ | |
883 | if (!scan_newer) | |
884 | /* | |
885 | * This can happen if a checkpoint was written without | |
886 | * barriers, or as a result of an I/O failure. | |
887 | */ | |
888 | goto failed; | |
889 | ||
890 | feed_segment: | |
891 | /* Looking to the next full segment */ | |
892 | if (empty_seg++) | |
893 | goto super_root_found; /* found a valid super root */ | |
894 | ||
895 | ent = nilfs_alloc_segment_entry(segnum); | |
896 | if (unlikely(!ent)) { | |
897 | ret = -ENOMEM; | |
898 | goto failed; | |
899 | } | |
900 | list_add_tail(&ent->list, &segments); | |
901 | ||
902 | seg_seq++; | |
903 | segnum = nextnum; | |
904 | nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); | |
905 | pseg_start = seg_start; | |
906 | } | |
907 | ||
908 | super_root_found: | |
909 | /* Updating pointers relating to the latest checkpoint */ | |
910 | list_splice(&segments, ri->ri_used_segments.prev); | |
911 | nilfs->ns_last_pseg = sr_pseg_start; | |
912 | nilfs->ns_last_seq = nilfs->ns_seg_seq; | |
913 | nilfs->ns_last_cno = ri->ri_cno; | |
914 | return 0; | |
915 | ||
916 | failed: | |
917 | nilfs_dispose_segment_list(&segments); | |
918 | return (ret < 0) ? ret : nilfs_warn_segment_error(ret); | |
919 | } |