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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> | |
5a0e3ad6 | 26 | #include <linux/slab.h> |
0f3e1c7f RK |
27 | #include <linux/crc32.h> |
28 | #include "nilfs.h" | |
29 | #include "segment.h" | |
30 | #include "sufile.h" | |
31 | #include "page.h" | |
0f3e1c7f RK |
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, | |
0f3e1c7f RK |
43 | NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT, |
44 | NILFS_SEG_FAIL_CHECKSUM_FULL, | |
45 | NILFS_SEG_FAIL_CONSISTENCY, | |
46 | }; | |
47 | ||
48 | /* work structure for recovery */ | |
49 | struct nilfs_recovery_block { | |
50 | ino_t ino; /* Inode number of the file that this block | |
51 | belongs to */ | |
52 | sector_t blocknr; /* block number */ | |
53 | __u64 vblocknr; /* virtual block number */ | |
54 | unsigned long blkoff; /* File offset of the data block (per block) */ | |
55 | struct list_head list; | |
56 | }; | |
57 | ||
58 | ||
59 | static int nilfs_warn_segment_error(int err) | |
60 | { | |
61 | switch (err) { | |
62 | case NILFS_SEG_FAIL_IO: | |
63 | printk(KERN_WARNING | |
64 | "NILFS warning: I/O error on loading last segment\n"); | |
65 | return -EIO; | |
66 | case NILFS_SEG_FAIL_MAGIC: | |
67 | printk(KERN_WARNING | |
68 | "NILFS warning: Segment magic number invalid\n"); | |
69 | break; | |
70 | case NILFS_SEG_FAIL_SEQ: | |
71 | printk(KERN_WARNING | |
72 | "NILFS warning: Sequence number mismatch\n"); | |
73 | break; | |
0f3e1c7f RK |
74 | case NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT: |
75 | printk(KERN_WARNING | |
76 | "NILFS warning: Checksum error in super root\n"); | |
77 | break; | |
78 | case NILFS_SEG_FAIL_CHECKSUM_FULL: | |
79 | printk(KERN_WARNING | |
80 | "NILFS warning: Checksum error in segment payload\n"); | |
81 | break; | |
82 | case NILFS_SEG_FAIL_CONSISTENCY: | |
83 | printk(KERN_WARNING | |
84 | "NILFS warning: Inconsistent segment\n"); | |
85 | break; | |
86 | case NILFS_SEG_NO_SUPER_ROOT: | |
87 | printk(KERN_WARNING | |
88 | "NILFS warning: No super root in the last segment\n"); | |
89 | break; | |
0f3e1c7f RK |
90 | } |
91 | return -EINVAL; | |
92 | } | |
93 | ||
94 | static void store_segsum_info(struct nilfs_segsum_info *ssi, | |
95 | struct nilfs_segment_summary *sum, | |
96 | unsigned int blocksize) | |
97 | { | |
98 | ssi->flags = le16_to_cpu(sum->ss_flags); | |
99 | ssi->seg_seq = le64_to_cpu(sum->ss_seq); | |
100 | ssi->ctime = le64_to_cpu(sum->ss_create); | |
101 | ssi->next = le64_to_cpu(sum->ss_next); | |
102 | ssi->nblocks = le32_to_cpu(sum->ss_nblocks); | |
103 | ssi->nfinfo = le32_to_cpu(sum->ss_nfinfo); | |
104 | ssi->sumbytes = le32_to_cpu(sum->ss_sumbytes); | |
105 | ||
106 | ssi->nsumblk = DIV_ROUND_UP(ssi->sumbytes, blocksize); | |
107 | ssi->nfileblk = ssi->nblocks - ssi->nsumblk - !!NILFS_SEG_HAS_SR(ssi); | |
108 | } | |
109 | ||
110 | /** | |
111 | * calc_crc_cont - check CRC of blocks continuously | |
112 | * @sbi: nilfs_sb_info | |
113 | * @bhs: buffer head of start block | |
114 | * @sum: place to store result | |
115 | * @offset: offset bytes in the first block | |
116 | * @check_bytes: number of bytes to be checked | |
117 | * @start: DBN of start block | |
118 | * @nblock: number of blocks to be checked | |
119 | */ | |
120 | static int calc_crc_cont(struct nilfs_sb_info *sbi, struct buffer_head *bhs, | |
121 | u32 *sum, unsigned long offset, u64 check_bytes, | |
122 | sector_t start, unsigned long nblock) | |
123 | { | |
124 | unsigned long blocksize = sbi->s_super->s_blocksize; | |
125 | unsigned long size; | |
126 | u32 crc; | |
127 | ||
128 | BUG_ON(offset >= blocksize); | |
129 | check_bytes -= offset; | |
130 | size = min_t(u64, check_bytes, blocksize - offset); | |
131 | crc = crc32_le(sbi->s_nilfs->ns_crc_seed, | |
132 | (unsigned char *)bhs->b_data + offset, size); | |
133 | if (--nblock > 0) { | |
134 | do { | |
135 | struct buffer_head *bh | |
136 | = sb_bread(sbi->s_super, ++start); | |
137 | if (!bh) | |
138 | return -EIO; | |
139 | check_bytes -= size; | |
140 | size = min_t(u64, check_bytes, blocksize); | |
141 | crc = crc32_le(crc, bh->b_data, size); | |
142 | brelse(bh); | |
143 | } while (--nblock > 0); | |
144 | } | |
145 | *sum = crc; | |
146 | return 0; | |
147 | } | |
148 | ||
149 | /** | |
150 | * nilfs_read_super_root_block - read super root block | |
151 | * @sb: super_block | |
152 | * @sr_block: disk block number of the super root block | |
153 | * @pbh: address of a buffer_head pointer to return super root buffer | |
154 | * @check: CRC check flag | |
155 | */ | |
156 | int nilfs_read_super_root_block(struct super_block *sb, sector_t sr_block, | |
157 | struct buffer_head **pbh, int check) | |
158 | { | |
159 | struct buffer_head *bh_sr; | |
160 | struct nilfs_super_root *sr; | |
161 | u32 crc; | |
162 | int ret; | |
163 | ||
164 | *pbh = NULL; | |
165 | bh_sr = sb_bread(sb, sr_block); | |
166 | if (unlikely(!bh_sr)) { | |
167 | ret = NILFS_SEG_FAIL_IO; | |
168 | goto failed; | |
169 | } | |
170 | ||
171 | sr = (struct nilfs_super_root *)bh_sr->b_data; | |
172 | if (check) { | |
173 | unsigned bytes = le16_to_cpu(sr->sr_bytes); | |
174 | ||
175 | if (bytes == 0 || bytes > sb->s_blocksize) { | |
176 | ret = NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT; | |
177 | goto failed_bh; | |
178 | } | |
179 | if (calc_crc_cont(NILFS_SB(sb), bh_sr, &crc, | |
180 | sizeof(sr->sr_sum), bytes, sr_block, 1)) { | |
181 | ret = NILFS_SEG_FAIL_IO; | |
182 | goto failed_bh; | |
183 | } | |
184 | if (crc != le32_to_cpu(sr->sr_sum)) { | |
185 | ret = NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT; | |
186 | goto failed_bh; | |
187 | } | |
188 | } | |
189 | *pbh = bh_sr; | |
190 | return 0; | |
191 | ||
192 | failed_bh: | |
193 | brelse(bh_sr); | |
194 | ||
195 | failed: | |
196 | return nilfs_warn_segment_error(ret); | |
197 | } | |
198 | ||
199 | /** | |
200 | * load_segment_summary - read segment summary of the specified partial segment | |
201 | * @sbi: nilfs_sb_info | |
202 | * @pseg_start: start disk block number of partial segment | |
203 | * @seg_seq: sequence number requested | |
204 | * @ssi: pointer to nilfs_segsum_info struct to store information | |
0f3e1c7f RK |
205 | */ |
206 | static int | |
207 | load_segment_summary(struct nilfs_sb_info *sbi, sector_t pseg_start, | |
03f29365 | 208 | u64 seg_seq, struct nilfs_segsum_info *ssi) |
0f3e1c7f RK |
209 | { |
210 | struct buffer_head *bh_sum; | |
211 | struct nilfs_segment_summary *sum; | |
03f29365 JS |
212 | unsigned long nblock; |
213 | u32 crc; | |
0f3e1c7f RK |
214 | int ret = NILFS_SEG_FAIL_IO; |
215 | ||
216 | bh_sum = sb_bread(sbi->s_super, pseg_start); | |
217 | if (!bh_sum) | |
218 | goto out; | |
219 | ||
220 | sum = (struct nilfs_segment_summary *)bh_sum->b_data; | |
221 | ||
222 | /* Check consistency of segment summary */ | |
223 | if (le32_to_cpu(sum->ss_magic) != NILFS_SEGSUM_MAGIC) { | |
224 | ret = NILFS_SEG_FAIL_MAGIC; | |
225 | goto failed; | |
226 | } | |
227 | store_segsum_info(ssi, sum, sbi->s_super->s_blocksize); | |
228 | if (seg_seq != ssi->seg_seq) { | |
229 | ret = NILFS_SEG_FAIL_SEQ; | |
230 | goto failed; | |
231 | } | |
0f3e1c7f | 232 | |
03f29365 | 233 | nblock = ssi->nblocks; |
0f3e1c7f RK |
234 | if (unlikely(nblock == 0 || |
235 | nblock > sbi->s_nilfs->ns_blocks_per_segment)) { | |
236 | /* This limits the number of blocks read in the CRC check */ | |
237 | ret = NILFS_SEG_FAIL_CONSISTENCY; | |
238 | goto failed; | |
239 | } | |
03f29365 JS |
240 | if (calc_crc_cont(sbi, bh_sum, &crc, sizeof(sum->ss_datasum), |
241 | ((u64)nblock << sbi->s_super->s_blocksize_bits), | |
0f3e1c7f RK |
242 | pseg_start, nblock)) { |
243 | ret = NILFS_SEG_FAIL_IO; | |
244 | goto failed; | |
245 | } | |
03f29365 | 246 | if (crc == le32_to_cpu(sum->ss_datasum)) |
0f3e1c7f | 247 | ret = 0; |
03f29365 JS |
248 | else |
249 | ret = NILFS_SEG_FAIL_CHECKSUM_FULL; | |
0f3e1c7f RK |
250 | failed: |
251 | brelse(bh_sum); | |
252 | out: | |
253 | return ret; | |
254 | } | |
255 | ||
256 | static void *segsum_get(struct super_block *sb, struct buffer_head **pbh, | |
257 | unsigned int *offset, unsigned int bytes) | |
258 | { | |
259 | void *ptr; | |
260 | sector_t blocknr; | |
261 | ||
262 | BUG_ON((*pbh)->b_size < *offset); | |
263 | if (bytes > (*pbh)->b_size - *offset) { | |
264 | blocknr = (*pbh)->b_blocknr; | |
265 | brelse(*pbh); | |
266 | *pbh = sb_bread(sb, blocknr + 1); | |
267 | if (unlikely(!*pbh)) | |
268 | return NULL; | |
269 | *offset = 0; | |
270 | } | |
271 | ptr = (*pbh)->b_data + *offset; | |
272 | *offset += bytes; | |
273 | return ptr; | |
274 | } | |
275 | ||
276 | static void segsum_skip(struct super_block *sb, struct buffer_head **pbh, | |
277 | unsigned int *offset, unsigned int bytes, | |
278 | unsigned long count) | |
279 | { | |
280 | unsigned int rest_item_in_current_block | |
281 | = ((*pbh)->b_size - *offset) / bytes; | |
282 | ||
283 | if (count <= rest_item_in_current_block) { | |
284 | *offset += bytes * count; | |
285 | } else { | |
286 | sector_t blocknr = (*pbh)->b_blocknr; | |
287 | unsigned int nitem_per_block = (*pbh)->b_size / bytes; | |
288 | unsigned int bcnt; | |
289 | ||
290 | count -= rest_item_in_current_block; | |
291 | bcnt = DIV_ROUND_UP(count, nitem_per_block); | |
292 | *offset = bytes * (count - (bcnt - 1) * nitem_per_block); | |
293 | ||
294 | brelse(*pbh); | |
295 | *pbh = sb_bread(sb, blocknr + bcnt); | |
296 | } | |
297 | } | |
298 | ||
299 | static int | |
300 | collect_blocks_from_segsum(struct nilfs_sb_info *sbi, sector_t sum_blocknr, | |
301 | struct nilfs_segsum_info *ssi, | |
302 | struct list_head *head) | |
303 | { | |
304 | struct buffer_head *bh; | |
305 | unsigned int offset; | |
306 | unsigned long nfinfo = ssi->nfinfo; | |
307 | sector_t blocknr = sum_blocknr + ssi->nsumblk; | |
308 | ino_t ino; | |
309 | int err = -EIO; | |
310 | ||
311 | if (!nfinfo) | |
312 | return 0; | |
313 | ||
314 | bh = sb_bread(sbi->s_super, sum_blocknr); | |
315 | if (unlikely(!bh)) | |
316 | goto out; | |
317 | ||
318 | offset = le16_to_cpu( | |
319 | ((struct nilfs_segment_summary *)bh->b_data)->ss_bytes); | |
320 | for (;;) { | |
321 | unsigned long nblocks, ndatablk, nnodeblk; | |
322 | struct nilfs_finfo *finfo; | |
323 | ||
324 | finfo = segsum_get(sbi->s_super, &bh, &offset, sizeof(*finfo)); | |
325 | if (unlikely(!finfo)) | |
326 | goto out; | |
327 | ||
328 | ino = le64_to_cpu(finfo->fi_ino); | |
329 | nblocks = le32_to_cpu(finfo->fi_nblocks); | |
330 | ndatablk = le32_to_cpu(finfo->fi_ndatablk); | |
331 | nnodeblk = nblocks - ndatablk; | |
332 | ||
333 | while (ndatablk-- > 0) { | |
334 | struct nilfs_recovery_block *rb; | |
335 | struct nilfs_binfo_v *binfo; | |
336 | ||
337 | binfo = segsum_get(sbi->s_super, &bh, &offset, | |
338 | sizeof(*binfo)); | |
339 | if (unlikely(!binfo)) | |
340 | goto out; | |
341 | ||
342 | rb = kmalloc(sizeof(*rb), GFP_NOFS); | |
343 | if (unlikely(!rb)) { | |
344 | err = -ENOMEM; | |
345 | goto out; | |
346 | } | |
347 | rb->ino = ino; | |
348 | rb->blocknr = blocknr++; | |
349 | rb->vblocknr = le64_to_cpu(binfo->bi_vblocknr); | |
350 | rb->blkoff = le64_to_cpu(binfo->bi_blkoff); | |
351 | /* INIT_LIST_HEAD(&rb->list); */ | |
352 | list_add_tail(&rb->list, head); | |
353 | } | |
354 | if (--nfinfo == 0) | |
355 | break; | |
356 | blocknr += nnodeblk; /* always 0 for the data sync segments */ | |
357 | segsum_skip(sbi->s_super, &bh, &offset, sizeof(__le64), | |
358 | nnodeblk); | |
359 | if (unlikely(!bh)) | |
360 | goto out; | |
361 | } | |
362 | err = 0; | |
363 | out: | |
364 | brelse(bh); /* brelse(NULL) is just ignored */ | |
365 | return err; | |
366 | } | |
367 | ||
368 | static void dispose_recovery_list(struct list_head *head) | |
369 | { | |
370 | while (!list_empty(head)) { | |
371 | struct nilfs_recovery_block *rb | |
372 | = list_entry(head->next, | |
373 | struct nilfs_recovery_block, list); | |
374 | list_del(&rb->list); | |
375 | kfree(rb); | |
376 | } | |
377 | } | |
378 | ||
654137dd RK |
379 | struct nilfs_segment_entry { |
380 | struct list_head list; | |
381 | __u64 segnum; | |
382 | }; | |
383 | ||
384 | static int nilfs_segment_list_add(struct list_head *head, __u64 segnum) | |
385 | { | |
386 | struct nilfs_segment_entry *ent = kmalloc(sizeof(*ent), GFP_NOFS); | |
387 | ||
388 | if (unlikely(!ent)) | |
389 | return -ENOMEM; | |
390 | ||
391 | ent->segnum = segnum; | |
392 | INIT_LIST_HEAD(&ent->list); | |
393 | list_add_tail(&ent->list, head); | |
394 | return 0; | |
395 | } | |
396 | ||
0f3e1c7f RK |
397 | void nilfs_dispose_segment_list(struct list_head *head) |
398 | { | |
399 | while (!list_empty(head)) { | |
400 | struct nilfs_segment_entry *ent | |
401 | = list_entry(head->next, | |
402 | struct nilfs_segment_entry, list); | |
403 | list_del(&ent->list); | |
654137dd | 404 | kfree(ent); |
0f3e1c7f RK |
405 | } |
406 | } | |
407 | ||
408 | static int nilfs_prepare_segment_for_recovery(struct the_nilfs *nilfs, | |
85c2a74f | 409 | struct nilfs_sb_info *sbi, |
0f3e1c7f RK |
410 | struct nilfs_recovery_info *ri) |
411 | { | |
412 | struct list_head *head = &ri->ri_used_segments; | |
413 | struct nilfs_segment_entry *ent, *n; | |
414 | struct inode *sufile = nilfs->ns_sufile; | |
415 | __u64 segnum[4]; | |
416 | int err; | |
417 | int i; | |
418 | ||
419 | segnum[0] = nilfs->ns_segnum; | |
420 | segnum[1] = nilfs->ns_nextnum; | |
421 | segnum[2] = ri->ri_segnum; | |
422 | segnum[3] = ri->ri_nextnum; | |
423 | ||
85c2a74f | 424 | nilfs_attach_writer(nilfs, sbi); |
0f3e1c7f RK |
425 | /* |
426 | * Releasing the next segment of the latest super root. | |
427 | * The next segment is invalidated by this recovery. | |
428 | */ | |
429 | err = nilfs_sufile_free(sufile, segnum[1]); | |
430 | if (unlikely(err)) | |
431 | goto failed; | |
432 | ||
0f3e1c7f | 433 | for (i = 1; i < 4; i++) { |
654137dd RK |
434 | err = nilfs_segment_list_add(head, segnum[i]); |
435 | if (unlikely(err)) | |
0f3e1c7f | 436 | goto failed; |
0f3e1c7f RK |
437 | } |
438 | ||
439 | /* | |
440 | * Collecting segments written after the latest super root. | |
2c2e52fc | 441 | * These are marked dirty to avoid being reallocated in the next write. |
0f3e1c7f RK |
442 | */ |
443 | list_for_each_entry_safe(ent, n, head, list) { | |
c85399c2 RK |
444 | if (ent->segnum != segnum[0]) { |
445 | err = nilfs_sufile_scrap(sufile, ent->segnum); | |
446 | if (unlikely(err)) | |
447 | goto failed; | |
0f3e1c7f | 448 | } |
2c2e52fc | 449 | list_del(&ent->list); |
654137dd | 450 | kfree(ent); |
0f3e1c7f | 451 | } |
0f3e1c7f | 452 | |
0f3e1c7f RK |
453 | /* Allocate new segments for recovery */ |
454 | err = nilfs_sufile_alloc(sufile, &segnum[0]); | |
455 | if (unlikely(err)) | |
456 | goto failed; | |
457 | ||
458 | nilfs->ns_pseg_offset = 0; | |
459 | nilfs->ns_seg_seq = ri->ri_seq + 2; | |
460 | nilfs->ns_nextnum = nilfs->ns_segnum = segnum[0]; | |
0f3e1c7f RK |
461 | |
462 | failed: | |
463 | /* No need to recover sufile because it will be destroyed on error */ | |
85c2a74f | 464 | nilfs_detach_writer(nilfs, sbi); |
0f3e1c7f RK |
465 | return err; |
466 | } | |
467 | ||
468 | static int nilfs_recovery_copy_block(struct nilfs_sb_info *sbi, | |
469 | struct nilfs_recovery_block *rb, | |
470 | struct page *page) | |
471 | { | |
472 | struct buffer_head *bh_org; | |
473 | void *kaddr; | |
474 | ||
475 | bh_org = sb_bread(sbi->s_super, rb->blocknr); | |
476 | if (unlikely(!bh_org)) | |
477 | return -EIO; | |
478 | ||
479 | kaddr = kmap_atomic(page, KM_USER0); | |
480 | memcpy(kaddr + bh_offset(bh_org), bh_org->b_data, bh_org->b_size); | |
481 | kunmap_atomic(kaddr, KM_USER0); | |
482 | brelse(bh_org); | |
483 | return 0; | |
484 | } | |
485 | ||
486 | static int recover_dsync_blocks(struct nilfs_sb_info *sbi, | |
487 | struct list_head *head, | |
488 | unsigned long *nr_salvaged_blocks) | |
489 | { | |
490 | struct inode *inode; | |
491 | struct nilfs_recovery_block *rb, *n; | |
492 | unsigned blocksize = sbi->s_super->s_blocksize; | |
493 | struct page *page; | |
494 | loff_t pos; | |
495 | int err = 0, err2 = 0; | |
496 | ||
497 | list_for_each_entry_safe(rb, n, head, list) { | |
498 | inode = nilfs_iget(sbi->s_super, rb->ino); | |
499 | if (IS_ERR(inode)) { | |
500 | err = PTR_ERR(inode); | |
501 | inode = NULL; | |
502 | goto failed_inode; | |
503 | } | |
504 | ||
505 | pos = rb->blkoff << inode->i_blkbits; | |
506 | page = NULL; | |
507 | err = block_write_begin(NULL, inode->i_mapping, pos, blocksize, | |
508 | 0, &page, NULL, nilfs_get_block); | |
509 | if (unlikely(err)) | |
510 | goto failed_inode; | |
511 | ||
512 | err = nilfs_recovery_copy_block(sbi, rb, page); | |
513 | if (unlikely(err)) | |
514 | goto failed_page; | |
515 | ||
516 | err = nilfs_set_file_dirty(sbi, inode, 1); | |
517 | if (unlikely(err)) | |
518 | goto failed_page; | |
519 | ||
520 | block_write_end(NULL, inode->i_mapping, pos, blocksize, | |
521 | blocksize, page, NULL); | |
522 | ||
523 | unlock_page(page); | |
524 | page_cache_release(page); | |
525 | ||
526 | (*nr_salvaged_blocks)++; | |
527 | goto next; | |
528 | ||
529 | failed_page: | |
530 | unlock_page(page); | |
531 | page_cache_release(page); | |
532 | ||
533 | failed_inode: | |
534 | printk(KERN_WARNING | |
535 | "NILFS warning: error recovering data block " | |
536 | "(err=%d, ino=%lu, block-offset=%llu)\n", | |
b5696e5e HC |
537 | err, (unsigned long)rb->ino, |
538 | (unsigned long long)rb->blkoff); | |
0f3e1c7f RK |
539 | if (!err2) |
540 | err2 = err; | |
541 | next: | |
542 | iput(inode); /* iput(NULL) is just ignored */ | |
543 | list_del_init(&rb->list); | |
544 | kfree(rb); | |
545 | } | |
546 | return err2; | |
547 | } | |
548 | ||
549 | /** | |
550 | * nilfs_do_roll_forward - salvage logical segments newer than the latest | |
551 | * checkpoint | |
552 | * @sbi: nilfs_sb_info | |
553 | * @nilfs: the_nilfs | |
554 | * @ri: pointer to a nilfs_recovery_info | |
555 | */ | |
556 | static int nilfs_do_roll_forward(struct the_nilfs *nilfs, | |
557 | struct nilfs_sb_info *sbi, | |
558 | struct nilfs_recovery_info *ri) | |
559 | { | |
560 | struct nilfs_segsum_info ssi; | |
561 | sector_t pseg_start; | |
562 | sector_t seg_start, seg_end; /* Starting/ending DBN of full segment */ | |
563 | unsigned long nsalvaged_blocks = 0; | |
564 | u64 seg_seq; | |
565 | __u64 segnum, nextnum = 0; | |
566 | int empty_seg = 0; | |
567 | int err = 0, ret; | |
568 | LIST_HEAD(dsync_blocks); /* list of data blocks to be recovered */ | |
569 | enum { | |
570 | RF_INIT_ST, | |
571 | RF_DSYNC_ST, /* scanning data-sync segments */ | |
572 | }; | |
573 | int state = RF_INIT_ST; | |
574 | ||
575 | nilfs_attach_writer(nilfs, sbi); | |
576 | pseg_start = ri->ri_lsegs_start; | |
577 | seg_seq = ri->ri_lsegs_start_seq; | |
578 | segnum = nilfs_get_segnum_of_block(nilfs, pseg_start); | |
579 | nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); | |
580 | ||
581 | while (segnum != ri->ri_segnum || pseg_start <= ri->ri_pseg_start) { | |
582 | ||
03f29365 | 583 | ret = load_segment_summary(sbi, pseg_start, seg_seq, &ssi); |
0f3e1c7f RK |
584 | if (ret) { |
585 | if (ret == NILFS_SEG_FAIL_IO) { | |
586 | err = -EIO; | |
587 | goto failed; | |
588 | } | |
589 | goto strayed; | |
590 | } | |
591 | if (unlikely(NILFS_SEG_HAS_SR(&ssi))) | |
592 | goto confused; | |
593 | ||
594 | /* Found a valid partial segment; do recovery actions */ | |
595 | nextnum = nilfs_get_segnum_of_block(nilfs, ssi.next); | |
596 | empty_seg = 0; | |
597 | nilfs->ns_ctime = ssi.ctime; | |
598 | if (!(ssi.flags & NILFS_SS_GC)) | |
599 | nilfs->ns_nongc_ctime = ssi.ctime; | |
600 | ||
601 | switch (state) { | |
602 | case RF_INIT_ST: | |
603 | if (!NILFS_SEG_LOGBGN(&ssi) || !NILFS_SEG_DSYNC(&ssi)) | |
604 | goto try_next_pseg; | |
605 | state = RF_DSYNC_ST; | |
606 | /* Fall through */ | |
607 | case RF_DSYNC_ST: | |
608 | if (!NILFS_SEG_DSYNC(&ssi)) | |
609 | goto confused; | |
610 | ||
611 | err = collect_blocks_from_segsum( | |
612 | sbi, pseg_start, &ssi, &dsync_blocks); | |
613 | if (unlikely(err)) | |
614 | goto failed; | |
615 | if (NILFS_SEG_LOGEND(&ssi)) { | |
616 | err = recover_dsync_blocks( | |
617 | sbi, &dsync_blocks, &nsalvaged_blocks); | |
618 | if (unlikely(err)) | |
619 | goto failed; | |
620 | state = RF_INIT_ST; | |
621 | } | |
622 | break; /* Fall through to try_next_pseg */ | |
623 | } | |
624 | ||
625 | try_next_pseg: | |
626 | if (pseg_start == ri->ri_lsegs_end) | |
627 | break; | |
628 | pseg_start += ssi.nblocks; | |
629 | if (pseg_start < seg_end) | |
630 | continue; | |
631 | goto feed_segment; | |
632 | ||
633 | strayed: | |
634 | if (pseg_start == ri->ri_lsegs_end) | |
635 | break; | |
636 | ||
637 | feed_segment: | |
638 | /* Looking to the next full segment */ | |
639 | if (empty_seg++) | |
640 | break; | |
641 | seg_seq++; | |
642 | segnum = nextnum; | |
643 | nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); | |
644 | pseg_start = seg_start; | |
645 | } | |
646 | ||
647 | if (nsalvaged_blocks) { | |
648 | printk(KERN_INFO "NILFS (device %s): salvaged %lu blocks\n", | |
649 | sbi->s_super->s_id, nsalvaged_blocks); | |
650 | ri->ri_need_recovery = NILFS_RECOVERY_ROLLFORWARD_DONE; | |
651 | } | |
652 | out: | |
653 | dispose_recovery_list(&dsync_blocks); | |
654 | nilfs_detach_writer(sbi->s_nilfs, sbi); | |
655 | return err; | |
656 | ||
657 | confused: | |
658 | err = -EINVAL; | |
659 | failed: | |
660 | printk(KERN_ERR | |
661 | "NILFS (device %s): Error roll-forwarding " | |
662 | "(err=%d, pseg block=%llu). ", | |
663 | sbi->s_super->s_id, err, (unsigned long long)pseg_start); | |
664 | goto out; | |
665 | } | |
666 | ||
667 | static void nilfs_finish_roll_forward(struct the_nilfs *nilfs, | |
668 | struct nilfs_sb_info *sbi, | |
669 | struct nilfs_recovery_info *ri) | |
670 | { | |
671 | struct buffer_head *bh; | |
672 | int err; | |
673 | ||
674 | if (nilfs_get_segnum_of_block(nilfs, ri->ri_lsegs_start) != | |
675 | nilfs_get_segnum_of_block(nilfs, ri->ri_super_root)) | |
676 | return; | |
677 | ||
678 | bh = sb_getblk(sbi->s_super, ri->ri_lsegs_start); | |
679 | BUG_ON(!bh); | |
680 | memset(bh->b_data, 0, bh->b_size); | |
681 | set_buffer_dirty(bh); | |
682 | err = sync_dirty_buffer(bh); | |
683 | if (unlikely(err)) | |
684 | printk(KERN_WARNING | |
685 | "NILFS warning: buffer sync write failed during " | |
686 | "post-cleaning of recovery.\n"); | |
687 | brelse(bh); | |
688 | } | |
689 | ||
690 | /** | |
691 | * nilfs_recover_logical_segments - salvage logical segments written after | |
692 | * the latest super root | |
693 | * @nilfs: the_nilfs | |
694 | * @sbi: nilfs_sb_info | |
695 | * @ri: pointer to a nilfs_recovery_info struct to store search results. | |
696 | * | |
697 | * Return Value: On success, 0 is returned. On error, one of the following | |
698 | * negative error code is returned. | |
699 | * | |
700 | * %-EINVAL - Inconsistent filesystem state. | |
701 | * | |
702 | * %-EIO - I/O error | |
703 | * | |
704 | * %-ENOSPC - No space left on device (only in a panic state). | |
705 | * | |
706 | * %-ERESTARTSYS - Interrupted. | |
707 | * | |
708 | * %-ENOMEM - Insufficient memory available. | |
709 | */ | |
710 | int nilfs_recover_logical_segments(struct the_nilfs *nilfs, | |
711 | struct nilfs_sb_info *sbi, | |
712 | struct nilfs_recovery_info *ri) | |
713 | { | |
714 | int err; | |
715 | ||
716 | if (ri->ri_lsegs_start == 0 || ri->ri_lsegs_end == 0) | |
717 | return 0; | |
718 | ||
719 | err = nilfs_attach_checkpoint(sbi, ri->ri_cno); | |
720 | if (unlikely(err)) { | |
721 | printk(KERN_ERR | |
722 | "NILFS: error loading the latest checkpoint.\n"); | |
723 | return err; | |
724 | } | |
725 | ||
726 | err = nilfs_do_roll_forward(nilfs, sbi, ri); | |
727 | if (unlikely(err)) | |
728 | goto failed; | |
729 | ||
730 | if (ri->ri_need_recovery == NILFS_RECOVERY_ROLLFORWARD_DONE) { | |
85c2a74f | 731 | err = nilfs_prepare_segment_for_recovery(nilfs, sbi, ri); |
0f3e1c7f RK |
732 | if (unlikely(err)) { |
733 | printk(KERN_ERR "NILFS: Error preparing segments for " | |
734 | "recovery.\n"); | |
735 | goto failed; | |
736 | } | |
737 | ||
cece5520 | 738 | err = nilfs_attach_segment_constructor(sbi); |
0f3e1c7f RK |
739 | if (unlikely(err)) |
740 | goto failed; | |
741 | ||
742 | set_nilfs_discontinued(nilfs); | |
743 | err = nilfs_construct_segment(sbi->s_super); | |
744 | nilfs_detach_segment_constructor(sbi); | |
745 | ||
746 | if (unlikely(err)) { | |
747 | printk(KERN_ERR "NILFS: Oops! recovery failed. " | |
748 | "(err=%d)\n", err); | |
749 | goto failed; | |
750 | } | |
751 | ||
752 | nilfs_finish_roll_forward(nilfs, sbi, ri); | |
753 | } | |
754 | ||
0f3e1c7f RK |
755 | failed: |
756 | nilfs_detach_checkpoint(sbi); | |
0f3e1c7f RK |
757 | return err; |
758 | } | |
759 | ||
760 | /** | |
761 | * nilfs_search_super_root - search the latest valid super root | |
762 | * @nilfs: the_nilfs | |
763 | * @sbi: nilfs_sb_info | |
764 | * @ri: pointer to a nilfs_recovery_info struct to store search results. | |
765 | * | |
766 | * nilfs_search_super_root() looks for the latest super-root from a partial | |
767 | * segment pointed by the superblock. It sets up struct the_nilfs through | |
768 | * this search. It fills nilfs_recovery_info (ri) required for recovery. | |
769 | * | |
770 | * Return Value: On success, 0 is returned. On error, one of the following | |
771 | * negative error code is returned. | |
772 | * | |
773 | * %-EINVAL - No valid segment found | |
774 | * | |
775 | * %-EIO - I/O error | |
776 | */ | |
777 | int nilfs_search_super_root(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi, | |
778 | struct nilfs_recovery_info *ri) | |
779 | { | |
780 | struct nilfs_segsum_info ssi; | |
781 | sector_t pseg_start, pseg_end, sr_pseg_start = 0; | |
782 | sector_t seg_start, seg_end; /* range of full segment (block number) */ | |
050b4142 | 783 | sector_t b, end; |
0f3e1c7f RK |
784 | u64 seg_seq; |
785 | __u64 segnum, nextnum = 0; | |
786 | __u64 cno; | |
0f3e1c7f RK |
787 | LIST_HEAD(segments); |
788 | int empty_seg = 0, scan_newer = 0; | |
789 | int ret; | |
790 | ||
791 | pseg_start = nilfs->ns_last_pseg; | |
792 | seg_seq = nilfs->ns_last_seq; | |
793 | cno = nilfs->ns_last_cno; | |
794 | segnum = nilfs_get_segnum_of_block(nilfs, pseg_start); | |
795 | ||
796 | /* Calculate range of segment */ | |
797 | nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); | |
798 | ||
050b4142 RK |
799 | /* Read ahead segment */ |
800 | b = seg_start; | |
801 | while (b <= seg_end) | |
802 | sb_breadahead(sbi->s_super, b++); | |
803 | ||
0f3e1c7f RK |
804 | for (;;) { |
805 | /* Load segment summary */ | |
03f29365 | 806 | ret = load_segment_summary(sbi, pseg_start, seg_seq, &ssi); |
0f3e1c7f RK |
807 | if (ret) { |
808 | if (ret == NILFS_SEG_FAIL_IO) | |
809 | goto failed; | |
810 | goto strayed; | |
811 | } | |
812 | pseg_end = pseg_start + ssi.nblocks - 1; | |
813 | if (unlikely(pseg_end > seg_end)) { | |
814 | ret = NILFS_SEG_FAIL_CONSISTENCY; | |
815 | goto strayed; | |
816 | } | |
817 | ||
818 | /* A valid partial segment */ | |
819 | ri->ri_pseg_start = pseg_start; | |
820 | ri->ri_seq = seg_seq; | |
821 | ri->ri_segnum = segnum; | |
822 | nextnum = nilfs_get_segnum_of_block(nilfs, ssi.next); | |
823 | ri->ri_nextnum = nextnum; | |
824 | empty_seg = 0; | |
825 | ||
050b4142 RK |
826 | if (!NILFS_SEG_HAS_SR(&ssi) && !scan_newer) { |
827 | /* This will never happen because a superblock | |
828 | (last_segment) always points to a pseg | |
829 | having a super root. */ | |
830 | ret = NILFS_SEG_FAIL_CONSISTENCY; | |
831 | goto failed; | |
832 | } | |
833 | ||
834 | if (pseg_start == seg_start) { | |
835 | nilfs_get_segment_range(nilfs, nextnum, &b, &end); | |
836 | while (b <= end) | |
837 | sb_breadahead(sbi->s_super, b++); | |
838 | } | |
0f3e1c7f | 839 | if (!NILFS_SEG_HAS_SR(&ssi)) { |
0f3e1c7f RK |
840 | if (!ri->ri_lsegs_start && NILFS_SEG_LOGBGN(&ssi)) { |
841 | ri->ri_lsegs_start = pseg_start; | |
842 | ri->ri_lsegs_start_seq = seg_seq; | |
843 | } | |
844 | if (NILFS_SEG_LOGEND(&ssi)) | |
845 | ri->ri_lsegs_end = pseg_start; | |
846 | goto try_next_pseg; | |
847 | } | |
848 | ||
849 | /* A valid super root was found. */ | |
850 | ri->ri_cno = cno++; | |
851 | ri->ri_super_root = pseg_end; | |
852 | ri->ri_lsegs_start = ri->ri_lsegs_end = 0; | |
853 | ||
854 | nilfs_dispose_segment_list(&segments); | |
855 | nilfs->ns_pseg_offset = (sr_pseg_start = pseg_start) | |
856 | + ssi.nblocks - seg_start; | |
857 | nilfs->ns_seg_seq = seg_seq; | |
858 | nilfs->ns_segnum = segnum; | |
859 | nilfs->ns_cno = cno; /* nilfs->ns_cno = ri->ri_cno + 1 */ | |
860 | nilfs->ns_ctime = ssi.ctime; | |
861 | nilfs->ns_nextnum = nextnum; | |
862 | ||
863 | if (scan_newer) | |
864 | ri->ri_need_recovery = NILFS_RECOVERY_SR_UPDATED; | |
2c2e52fc | 865 | else { |
2c2e52fc RK |
866 | if (nilfs->ns_mount_state & NILFS_VALID_FS) |
867 | goto super_root_found; | |
868 | scan_newer = 1; | |
869 | } | |
0f3e1c7f RK |
870 | |
871 | /* reset region for roll-forward */ | |
872 | pseg_start += ssi.nblocks; | |
873 | if (pseg_start < seg_end) | |
874 | continue; | |
875 | goto feed_segment; | |
876 | ||
877 | try_next_pseg: | |
878 | /* Standing on a course, or met an inconsistent state */ | |
879 | pseg_start += ssi.nblocks; | |
880 | if (pseg_start < seg_end) | |
881 | continue; | |
882 | goto feed_segment; | |
883 | ||
884 | strayed: | |
885 | /* Off the trail */ | |
886 | if (!scan_newer) | |
887 | /* | |
888 | * This can happen if a checkpoint was written without | |
889 | * barriers, or as a result of an I/O failure. | |
890 | */ | |
891 | goto failed; | |
892 | ||
893 | feed_segment: | |
894 | /* Looking to the next full segment */ | |
895 | if (empty_seg++) | |
896 | goto super_root_found; /* found a valid super root */ | |
897 | ||
654137dd RK |
898 | ret = nilfs_segment_list_add(&segments, segnum); |
899 | if (unlikely(ret)) | |
0f3e1c7f | 900 | goto failed; |
0f3e1c7f RK |
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 */ | |
0935db74 | 910 | list_splice_tail(&segments, &ri->ri_used_segments); |
0f3e1c7f RK |
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 | } |