1 // SPDX-License-Identifier: GPL-2.0
2
3 #include "bcachefs.h"
4 #include "bkey_buf.h"
5 #include "btree_cache.h"
6 #include "btree_update.h"
7 #include "buckets.h"
8 #include "darray.h"
9 #include "dirent.h"
10 #include "error.h"
11 #include "fs.h"
12 #include "fs-common.h"
13 #include "fsck.h"
14 #include "inode.h"
15 #include "keylist.h"
16 #include "recovery_passes.h"
17 #include "snapshot.h"
18 #include "super.h"
19 #include "xattr.h"
20
21 #include <linux/bsearch.h>
22 #include <linux/dcache.h> /* struct qstr */
23
inode_points_to_dirent(struct bch_inode_unpacked * inode,struct bkey_s_c_dirent d)24 static bool inode_points_to_dirent(struct bch_inode_unpacked *inode,
25 struct bkey_s_c_dirent d)
26 {
27 return inode->bi_dir == d.k->p.inode &&
28 inode->bi_dir_offset == d.k->p.offset;
29 }
30
dirent_points_to_inode_nowarn(struct bkey_s_c_dirent d,struct bch_inode_unpacked * inode)31 static bool dirent_points_to_inode_nowarn(struct bkey_s_c_dirent d,
32 struct bch_inode_unpacked *inode)
33 {
34 if (d.v->d_type == DT_SUBVOL
35 ? le32_to_cpu(d.v->d_child_subvol) == inode->bi_subvol
36 : le64_to_cpu(d.v->d_inum) == inode->bi_inum)
37 return 0;
38 return -BCH_ERR_ENOENT_dirent_doesnt_match_inode;
39 }
40
dirent_inode_mismatch_msg(struct printbuf * out,struct bch_fs * c,struct bkey_s_c_dirent dirent,struct bch_inode_unpacked * inode)41 static void dirent_inode_mismatch_msg(struct printbuf *out,
42 struct bch_fs *c,
43 struct bkey_s_c_dirent dirent,
44 struct bch_inode_unpacked *inode)
45 {
46 prt_str(out, "inode points to dirent that does not point back:");
47 prt_newline(out);
48 bch2_bkey_val_to_text(out, c, dirent.s_c);
49 prt_newline(out);
50 bch2_inode_unpacked_to_text(out, inode);
51 }
52
dirent_points_to_inode(struct bch_fs * c,struct bkey_s_c_dirent dirent,struct bch_inode_unpacked * inode)53 static int dirent_points_to_inode(struct bch_fs *c,
54 struct bkey_s_c_dirent dirent,
55 struct bch_inode_unpacked *inode)
56 {
57 int ret = dirent_points_to_inode_nowarn(dirent, inode);
58 if (ret) {
59 struct printbuf buf = PRINTBUF;
60 dirent_inode_mismatch_msg(&buf, c, dirent, inode);
61 bch_warn(c, "%s", buf.buf);
62 printbuf_exit(&buf);
63 }
64 return ret;
65 }
66
67 /*
68 * XXX: this is handling transaction restarts without returning
69 * -BCH_ERR_transaction_restart_nested, this is not how we do things anymore:
70 */
bch2_count_inode_sectors(struct btree_trans * trans,u64 inum,u32 snapshot)71 static s64 bch2_count_inode_sectors(struct btree_trans *trans, u64 inum,
72 u32 snapshot)
73 {
74 u64 sectors = 0;
75
76 int ret = for_each_btree_key_upto(trans, iter, BTREE_ID_extents,
77 SPOS(inum, 0, snapshot),
78 POS(inum, U64_MAX),
79 0, k, ({
80 if (bkey_extent_is_allocation(k.k))
81 sectors += k.k->size;
82 0;
83 }));
84
85 return ret ?: sectors;
86 }
87
bch2_count_subdirs(struct btree_trans * trans,u64 inum,u32 snapshot)88 static s64 bch2_count_subdirs(struct btree_trans *trans, u64 inum,
89 u32 snapshot)
90 {
91 u64 subdirs = 0;
92
93 int ret = for_each_btree_key_upto(trans, iter, BTREE_ID_dirents,
94 SPOS(inum, 0, snapshot),
95 POS(inum, U64_MAX),
96 0, k, ({
97 if (k.k->type == KEY_TYPE_dirent &&
98 bkey_s_c_to_dirent(k).v->d_type == DT_DIR)
99 subdirs++;
100 0;
101 }));
102
103 return ret ?: subdirs;
104 }
105
subvol_lookup(struct btree_trans * trans,u32 subvol,u32 * snapshot,u64 * inum)106 static int subvol_lookup(struct btree_trans *trans, u32 subvol,
107 u32 *snapshot, u64 *inum)
108 {
109 struct bch_subvolume s;
110 int ret = bch2_subvolume_get(trans, subvol, false, 0, &s);
111
112 *snapshot = le32_to_cpu(s.snapshot);
113 *inum = le64_to_cpu(s.inode);
114 return ret;
115 }
116
lookup_first_inode(struct btree_trans * trans,u64 inode_nr,struct bch_inode_unpacked * inode)117 static int lookup_first_inode(struct btree_trans *trans, u64 inode_nr,
118 struct bch_inode_unpacked *inode)
119 {
120 struct btree_iter iter;
121 struct bkey_s_c k;
122 int ret;
123
124 for_each_btree_key_norestart(trans, iter, BTREE_ID_inodes, POS(0, inode_nr),
125 BTREE_ITER_all_snapshots, k, ret) {
126 if (k.k->p.offset != inode_nr)
127 break;
128 if (!bkey_is_inode(k.k))
129 continue;
130 ret = bch2_inode_unpack(k, inode);
131 goto found;
132 }
133 ret = -BCH_ERR_ENOENT_inode;
134 found:
135 bch_err_msg(trans->c, ret, "fetching inode %llu", inode_nr);
136 bch2_trans_iter_exit(trans, &iter);
137 return ret;
138 }
139
lookup_inode(struct btree_trans * trans,u64 inode_nr,struct bch_inode_unpacked * inode,u32 * snapshot)140 static int lookup_inode(struct btree_trans *trans, u64 inode_nr,
141 struct bch_inode_unpacked *inode,
142 u32 *snapshot)
143 {
144 struct btree_iter iter;
145 struct bkey_s_c k;
146 int ret;
147
148 k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_inodes,
149 SPOS(0, inode_nr, *snapshot), 0);
150 ret = bkey_err(k);
151 if (ret)
152 goto err;
153
154 ret = bkey_is_inode(k.k)
155 ? bch2_inode_unpack(k, inode)
156 : -BCH_ERR_ENOENT_inode;
157 if (!ret)
158 *snapshot = iter.pos.snapshot;
159 err:
160 bch2_trans_iter_exit(trans, &iter);
161 return ret;
162 }
163
lookup_dirent_in_snapshot(struct btree_trans * trans,struct bch_hash_info hash_info,subvol_inum dir,struct qstr * name,u64 * target,unsigned * type,u32 snapshot)164 static int lookup_dirent_in_snapshot(struct btree_trans *trans,
165 struct bch_hash_info hash_info,
166 subvol_inum dir, struct qstr *name,
167 u64 *target, unsigned *type, u32 snapshot)
168 {
169 struct btree_iter iter;
170 struct bkey_s_c k = bch2_hash_lookup_in_snapshot(trans, &iter, bch2_dirent_hash_desc,
171 &hash_info, dir, name, 0, snapshot);
172 int ret = bkey_err(k);
173 if (ret)
174 return ret;
175
176 struct bkey_s_c_dirent d = bkey_s_c_to_dirent(bch2_btree_iter_peek_slot(&iter));
177 *target = le64_to_cpu(d.v->d_inum);
178 *type = d.v->d_type;
179 bch2_trans_iter_exit(trans, &iter);
180 return 0;
181 }
182
__remove_dirent(struct btree_trans * trans,struct bpos pos)183 static int __remove_dirent(struct btree_trans *trans, struct bpos pos)
184 {
185 struct bch_fs *c = trans->c;
186 struct btree_iter iter;
187 struct bch_inode_unpacked dir_inode;
188 struct bch_hash_info dir_hash_info;
189 int ret;
190
191 ret = lookup_first_inode(trans, pos.inode, &dir_inode);
192 if (ret)
193 goto err;
194
195 dir_hash_info = bch2_hash_info_init(c, &dir_inode);
196
197 bch2_trans_iter_init(trans, &iter, BTREE_ID_dirents, pos, BTREE_ITER_intent);
198
199 ret = bch2_btree_iter_traverse(&iter) ?:
200 bch2_hash_delete_at(trans, bch2_dirent_hash_desc,
201 &dir_hash_info, &iter,
202 BTREE_UPDATE_internal_snapshot_node);
203 bch2_trans_iter_exit(trans, &iter);
204 err:
205 bch_err_fn(c, ret);
206 return ret;
207 }
208
209 /* Get lost+found, create if it doesn't exist: */
lookup_lostfound(struct btree_trans * trans,u32 snapshot,struct bch_inode_unpacked * lostfound,u64 reattaching_inum)210 static int lookup_lostfound(struct btree_trans *trans, u32 snapshot,
211 struct bch_inode_unpacked *lostfound,
212 u64 reattaching_inum)
213 {
214 struct bch_fs *c = trans->c;
215 struct qstr lostfound_str = QSTR("lost+found");
216 u64 inum = 0;
217 unsigned d_type = 0;
218 int ret;
219
220 struct bch_snapshot_tree st;
221 ret = bch2_snapshot_tree_lookup(trans,
222 bch2_snapshot_tree(c, snapshot), &st);
223 if (ret)
224 return ret;
225
226 subvol_inum root_inum = { .subvol = le32_to_cpu(st.master_subvol) };
227
228 struct bch_subvolume subvol;
229 ret = bch2_subvolume_get(trans, le32_to_cpu(st.master_subvol),
230 false, 0, &subvol);
231 bch_err_msg(c, ret, "looking up root subvol %u for snapshot %u",
232 le32_to_cpu(st.master_subvol), snapshot);
233 if (ret)
234 return ret;
235
236 if (!subvol.inode) {
237 struct btree_iter iter;
238 struct bkey_i_subvolume *subvol = bch2_bkey_get_mut_typed(trans, &iter,
239 BTREE_ID_subvolumes, POS(0, le32_to_cpu(st.master_subvol)),
240 0, subvolume);
241 ret = PTR_ERR_OR_ZERO(subvol);
242 if (ret)
243 return ret;
244
245 subvol->v.inode = cpu_to_le64(reattaching_inum);
246 bch2_trans_iter_exit(trans, &iter);
247 }
248
249 root_inum.inum = le64_to_cpu(subvol.inode);
250
251 struct bch_inode_unpacked root_inode;
252 struct bch_hash_info root_hash_info;
253 u32 root_inode_snapshot = snapshot;
254 ret = lookup_inode(trans, root_inum.inum, &root_inode, &root_inode_snapshot);
255 bch_err_msg(c, ret, "looking up root inode %llu for subvol %u",
256 root_inum.inum, le32_to_cpu(st.master_subvol));
257 if (ret)
258 return ret;
259
260 root_hash_info = bch2_hash_info_init(c, &root_inode);
261
262 ret = lookup_dirent_in_snapshot(trans, root_hash_info, root_inum,
263 &lostfound_str, &inum, &d_type, snapshot);
264 if (bch2_err_matches(ret, ENOENT))
265 goto create_lostfound;
266
267 bch_err_fn(c, ret);
268 if (ret)
269 return ret;
270
271 if (d_type != DT_DIR) {
272 bch_err(c, "error looking up lost+found: not a directory");
273 return -BCH_ERR_ENOENT_not_directory;
274 }
275
276 /*
277 * The bch2_check_dirents pass has already run, dangling dirents
278 * shouldn't exist here:
279 */
280 ret = lookup_inode(trans, inum, lostfound, &snapshot);
281 bch_err_msg(c, ret, "looking up lost+found %llu:%u in (root inode %llu, snapshot root %u)",
282 inum, snapshot, root_inum.inum, bch2_snapshot_root(c, snapshot));
283 return ret;
284
285 create_lostfound:
286 /*
287 * XXX: we could have a nicer log message here if we had a nice way to
288 * walk backpointers to print a path
289 */
290 bch_notice(c, "creating lost+found in snapshot %u", le32_to_cpu(st.root_snapshot));
291
292 u64 now = bch2_current_time(c);
293 struct btree_iter lostfound_iter = { NULL };
294 u64 cpu = raw_smp_processor_id();
295
296 bch2_inode_init_early(c, lostfound);
297 bch2_inode_init_late(lostfound, now, 0, 0, S_IFDIR|0700, 0, &root_inode);
298 lostfound->bi_dir = root_inode.bi_inum;
299
300 root_inode.bi_nlink++;
301
302 ret = bch2_inode_create(trans, &lostfound_iter, lostfound, snapshot, cpu);
303 if (ret)
304 goto err;
305
306 bch2_btree_iter_set_snapshot(&lostfound_iter, snapshot);
307 ret = bch2_btree_iter_traverse(&lostfound_iter);
308 if (ret)
309 goto err;
310
311 ret = bch2_dirent_create_snapshot(trans,
312 0, root_inode.bi_inum, snapshot, &root_hash_info,
313 mode_to_type(lostfound->bi_mode),
314 &lostfound_str,
315 lostfound->bi_inum,
316 &lostfound->bi_dir_offset,
317 STR_HASH_must_create) ?:
318 bch2_inode_write_flags(trans, &lostfound_iter, lostfound,
319 BTREE_UPDATE_internal_snapshot_node);
320 err:
321 bch_err_msg(c, ret, "creating lost+found");
322 bch2_trans_iter_exit(trans, &lostfound_iter);
323 return ret;
324 }
325
reattach_inode(struct btree_trans * trans,struct bch_inode_unpacked * inode,u32 inode_snapshot)326 static int reattach_inode(struct btree_trans *trans,
327 struct bch_inode_unpacked *inode,
328 u32 inode_snapshot)
329 {
330 struct bch_fs *c = trans->c;
331 struct bch_hash_info dir_hash;
332 struct bch_inode_unpacked lostfound;
333 char name_buf[20];
334 struct qstr name;
335 u64 dir_offset = 0;
336 u32 dirent_snapshot = inode_snapshot;
337 int ret;
338
339 if (inode->bi_subvol) {
340 inode->bi_parent_subvol = BCACHEFS_ROOT_SUBVOL;
341
342 u64 root_inum;
343 ret = subvol_lookup(trans, inode->bi_parent_subvol,
344 &dirent_snapshot, &root_inum);
345 if (ret)
346 return ret;
347
348 snprintf(name_buf, sizeof(name_buf), "subvol-%u", inode->bi_subvol);
349 } else {
350 snprintf(name_buf, sizeof(name_buf), "%llu", inode->bi_inum);
351 }
352
353 ret = lookup_lostfound(trans, dirent_snapshot, &lostfound, inode->bi_inum);
354 if (ret)
355 return ret;
356
357 if (S_ISDIR(inode->bi_mode)) {
358 lostfound.bi_nlink++;
359
360 ret = __bch2_fsck_write_inode(trans, &lostfound, U32_MAX);
361 if (ret)
362 return ret;
363 }
364
365 dir_hash = bch2_hash_info_init(c, &lostfound);
366
367 name = (struct qstr) QSTR(name_buf);
368
369 ret = bch2_dirent_create_snapshot(trans,
370 inode->bi_parent_subvol, lostfound.bi_inum,
371 dirent_snapshot,
372 &dir_hash,
373 inode_d_type(inode),
374 &name,
375 inode->bi_subvol ?: inode->bi_inum,
376 &dir_offset,
377 STR_HASH_must_create);
378 if (ret) {
379 bch_err_msg(c, ret, "error creating dirent");
380 return ret;
381 }
382
383 inode->bi_dir = lostfound.bi_inum;
384 inode->bi_dir_offset = dir_offset;
385
386 return __bch2_fsck_write_inode(trans, inode, inode_snapshot);
387 }
388
remove_backpointer(struct btree_trans * trans,struct bch_inode_unpacked * inode)389 static int remove_backpointer(struct btree_trans *trans,
390 struct bch_inode_unpacked *inode)
391 {
392 if (!inode->bi_dir)
393 return 0;
394
395 struct bch_fs *c = trans->c;
396 struct btree_iter iter;
397 struct bkey_s_c_dirent d =
398 bch2_bkey_get_iter_typed(trans, &iter, BTREE_ID_dirents,
399 SPOS(inode->bi_dir, inode->bi_dir_offset, inode->bi_snapshot), 0,
400 dirent);
401 int ret = bkey_err(d) ?:
402 dirent_points_to_inode(c, d, inode) ?:
403 __remove_dirent(trans, d.k->p);
404 bch2_trans_iter_exit(trans, &iter);
405 return ret;
406 }
407
reattach_subvol(struct btree_trans * trans,struct bkey_s_c_subvolume s)408 static int reattach_subvol(struct btree_trans *trans, struct bkey_s_c_subvolume s)
409 {
410 struct bch_fs *c = trans->c;
411
412 struct bch_inode_unpacked inode;
413 int ret = bch2_inode_find_by_inum_trans(trans,
414 (subvol_inum) { s.k->p.offset, le64_to_cpu(s.v->inode) },
415 &inode);
416 if (ret)
417 return ret;
418
419 ret = remove_backpointer(trans, &inode);
420 if (!bch2_err_matches(ret, ENOENT))
421 bch_err_msg(c, ret, "removing dirent");
422 if (ret)
423 return ret;
424
425 ret = reattach_inode(trans, &inode, le32_to_cpu(s.v->snapshot));
426 bch_err_msg(c, ret, "reattaching inode %llu", inode.bi_inum);
427 return ret;
428 }
429
reconstruct_subvol(struct btree_trans * trans,u32 snapshotid,u32 subvolid,u64 inum)430 static int reconstruct_subvol(struct btree_trans *trans, u32 snapshotid, u32 subvolid, u64 inum)
431 {
432 struct bch_fs *c = trans->c;
433
434 if (!bch2_snapshot_is_leaf(c, snapshotid)) {
435 bch_err(c, "need to reconstruct subvol, but have interior node snapshot");
436 return -BCH_ERR_fsck_repair_unimplemented;
437 }
438
439 /*
440 * If inum isn't set, that means we're being called from check_dirents,
441 * not check_inodes - the root of this subvolume doesn't exist or we
442 * would have found it there:
443 */
444 if (!inum) {
445 struct btree_iter inode_iter = {};
446 struct bch_inode_unpacked new_inode;
447 u64 cpu = raw_smp_processor_id();
448
449 bch2_inode_init_early(c, &new_inode);
450 bch2_inode_init_late(&new_inode, bch2_current_time(c), 0, 0, S_IFDIR|0755, 0, NULL);
451
452 new_inode.bi_subvol = subvolid;
453
454 int ret = bch2_inode_create(trans, &inode_iter, &new_inode, snapshotid, cpu) ?:
455 bch2_btree_iter_traverse(&inode_iter) ?:
456 bch2_inode_write(trans, &inode_iter, &new_inode);
457 bch2_trans_iter_exit(trans, &inode_iter);
458 if (ret)
459 return ret;
460
461 inum = new_inode.bi_inum;
462 }
463
464 bch_info(c, "reconstructing subvol %u with root inode %llu", subvolid, inum);
465
466 struct bkey_i_subvolume *new_subvol = bch2_trans_kmalloc(trans, sizeof(*new_subvol));
467 int ret = PTR_ERR_OR_ZERO(new_subvol);
468 if (ret)
469 return ret;
470
471 bkey_subvolume_init(&new_subvol->k_i);
472 new_subvol->k.p.offset = subvolid;
473 new_subvol->v.snapshot = cpu_to_le32(snapshotid);
474 new_subvol->v.inode = cpu_to_le64(inum);
475 ret = bch2_btree_insert_trans(trans, BTREE_ID_subvolumes, &new_subvol->k_i, 0);
476 if (ret)
477 return ret;
478
479 struct btree_iter iter;
480 struct bkey_i_snapshot *s = bch2_bkey_get_mut_typed(trans, &iter,
481 BTREE_ID_snapshots, POS(0, snapshotid),
482 0, snapshot);
483 ret = PTR_ERR_OR_ZERO(s);
484 bch_err_msg(c, ret, "getting snapshot %u", snapshotid);
485 if (ret)
486 return ret;
487
488 u32 snapshot_tree = le32_to_cpu(s->v.tree);
489
490 s->v.subvol = cpu_to_le32(subvolid);
491 SET_BCH_SNAPSHOT_SUBVOL(&s->v, true);
492 bch2_trans_iter_exit(trans, &iter);
493
494 struct bkey_i_snapshot_tree *st = bch2_bkey_get_mut_typed(trans, &iter,
495 BTREE_ID_snapshot_trees, POS(0, snapshot_tree),
496 0, snapshot_tree);
497 ret = PTR_ERR_OR_ZERO(st);
498 bch_err_msg(c, ret, "getting snapshot tree %u", snapshot_tree);
499 if (ret)
500 return ret;
501
502 if (!st->v.master_subvol)
503 st->v.master_subvol = cpu_to_le32(subvolid);
504
505 bch2_trans_iter_exit(trans, &iter);
506 return 0;
507 }
508
reconstruct_inode(struct btree_trans * trans,enum btree_id btree,u32 snapshot,u64 inum)509 static int reconstruct_inode(struct btree_trans *trans, enum btree_id btree, u32 snapshot, u64 inum)
510 {
511 struct bch_fs *c = trans->c;
512 unsigned i_mode = S_IFREG;
513 u64 i_size = 0;
514
515 switch (btree) {
516 case BTREE_ID_extents: {
517 struct btree_iter iter = {};
518
519 bch2_trans_iter_init(trans, &iter, BTREE_ID_extents, SPOS(inum, U64_MAX, snapshot), 0);
520 struct bkey_s_c k = bch2_btree_iter_peek_prev(&iter);
521 bch2_trans_iter_exit(trans, &iter);
522 int ret = bkey_err(k);
523 if (ret)
524 return ret;
525
526 i_size = k.k->p.offset << 9;
527 break;
528 }
529 case BTREE_ID_dirents:
530 i_mode = S_IFDIR;
531 break;
532 case BTREE_ID_xattrs:
533 break;
534 default:
535 BUG();
536 }
537
538 struct bch_inode_unpacked new_inode;
539 bch2_inode_init_early(c, &new_inode);
540 bch2_inode_init_late(&new_inode, bch2_current_time(c), 0, 0, i_mode|0600, 0, NULL);
541 new_inode.bi_size = i_size;
542 new_inode.bi_inum = inum;
543
544 return __bch2_fsck_write_inode(trans, &new_inode, snapshot);
545 }
546
547 struct snapshots_seen {
548 struct bpos pos;
549 snapshot_id_list ids;
550 };
551
snapshots_seen_exit(struct snapshots_seen * s)552 static inline void snapshots_seen_exit(struct snapshots_seen *s)
553 {
554 darray_exit(&s->ids);
555 }
556
snapshots_seen_init(struct snapshots_seen * s)557 static inline void snapshots_seen_init(struct snapshots_seen *s)
558 {
559 memset(s, 0, sizeof(*s));
560 }
561
snapshots_seen_add_inorder(struct bch_fs * c,struct snapshots_seen * s,u32 id)562 static int snapshots_seen_add_inorder(struct bch_fs *c, struct snapshots_seen *s, u32 id)
563 {
564 u32 *i;
565 __darray_for_each(s->ids, i) {
566 if (*i == id)
567 return 0;
568 if (*i > id)
569 break;
570 }
571
572 int ret = darray_insert_item(&s->ids, i - s->ids.data, id);
573 if (ret)
574 bch_err(c, "error reallocating snapshots_seen table (size %zu)",
575 s->ids.size);
576 return ret;
577 }
578
snapshots_seen_update(struct bch_fs * c,struct snapshots_seen * s,enum btree_id btree_id,struct bpos pos)579 static int snapshots_seen_update(struct bch_fs *c, struct snapshots_seen *s,
580 enum btree_id btree_id, struct bpos pos)
581 {
582 if (!bkey_eq(s->pos, pos))
583 s->ids.nr = 0;
584 s->pos = pos;
585
586 return snapshot_list_add_nodup(c, &s->ids, pos.snapshot);
587 }
588
589 /**
590 * key_visible_in_snapshot - returns true if @id is a descendent of @ancestor,
591 * and @ancestor hasn't been overwritten in @seen
592 *
593 * @c: filesystem handle
594 * @seen: list of snapshot ids already seen at current position
595 * @id: descendent snapshot id
596 * @ancestor: ancestor snapshot id
597 *
598 * Returns: whether key in @ancestor snapshot is visible in @id snapshot
599 */
key_visible_in_snapshot(struct bch_fs * c,struct snapshots_seen * seen,u32 id,u32 ancestor)600 static bool key_visible_in_snapshot(struct bch_fs *c, struct snapshots_seen *seen,
601 u32 id, u32 ancestor)
602 {
603 ssize_t i;
604
605 EBUG_ON(id > ancestor);
606
607 /* @ancestor should be the snapshot most recently added to @seen */
608 EBUG_ON(ancestor != seen->pos.snapshot);
609 EBUG_ON(ancestor != darray_last(seen->ids));
610
611 if (id == ancestor)
612 return true;
613
614 if (!bch2_snapshot_is_ancestor(c, id, ancestor))
615 return false;
616
617 /*
618 * We know that @id is a descendant of @ancestor, we're checking if
619 * we've seen a key that overwrote @ancestor - i.e. also a descendent of
620 * @ascestor and with @id as a descendent.
621 *
622 * But we already know that we're scanning IDs between @id and @ancestor
623 * numerically, since snapshot ID lists are kept sorted, so if we find
624 * an id that's an ancestor of @id we're done:
625 */
626
627 for (i = seen->ids.nr - 2;
628 i >= 0 && seen->ids.data[i] >= id;
629 --i)
630 if (bch2_snapshot_is_ancestor(c, id, seen->ids.data[i]))
631 return false;
632
633 return true;
634 }
635
636 /**
637 * ref_visible - given a key with snapshot id @src that points to a key with
638 * snapshot id @dst, test whether there is some snapshot in which @dst is
639 * visible.
640 *
641 * @c: filesystem handle
642 * @s: list of snapshot IDs already seen at @src
643 * @src: snapshot ID of src key
644 * @dst: snapshot ID of dst key
645 * Returns: true if there is some snapshot in which @dst is visible
646 *
647 * Assumes we're visiting @src keys in natural key order
648 */
ref_visible(struct bch_fs * c,struct snapshots_seen * s,u32 src,u32 dst)649 static bool ref_visible(struct bch_fs *c, struct snapshots_seen *s,
650 u32 src, u32 dst)
651 {
652 return dst <= src
653 ? key_visible_in_snapshot(c, s, dst, src)
654 : bch2_snapshot_is_ancestor(c, src, dst);
655 }
656
ref_visible2(struct bch_fs * c,u32 src,struct snapshots_seen * src_seen,u32 dst,struct snapshots_seen * dst_seen)657 static int ref_visible2(struct bch_fs *c,
658 u32 src, struct snapshots_seen *src_seen,
659 u32 dst, struct snapshots_seen *dst_seen)
660 {
661 if (dst > src) {
662 swap(dst, src);
663 swap(dst_seen, src_seen);
664 }
665 return key_visible_in_snapshot(c, src_seen, dst, src);
666 }
667
668 #define for_each_visible_inode(_c, _s, _w, _snapshot, _i) \
669 for (_i = (_w)->inodes.data; _i < (_w)->inodes.data + (_w)->inodes.nr && \
670 (_i)->snapshot <= (_snapshot); _i++) \
671 if (key_visible_in_snapshot(_c, _s, _i->snapshot, _snapshot))
672
673 struct inode_walker_entry {
674 struct bch_inode_unpacked inode;
675 u32 snapshot;
676 u64 count;
677 };
678
679 struct inode_walker {
680 bool first_this_inode;
681 bool have_inodes;
682 bool recalculate_sums;
683 struct bpos last_pos;
684
685 DARRAY(struct inode_walker_entry) inodes;
686 };
687
inode_walker_exit(struct inode_walker * w)688 static void inode_walker_exit(struct inode_walker *w)
689 {
690 darray_exit(&w->inodes);
691 }
692
inode_walker_init(void)693 static struct inode_walker inode_walker_init(void)
694 {
695 return (struct inode_walker) { 0, };
696 }
697
add_inode(struct bch_fs * c,struct inode_walker * w,struct bkey_s_c inode)698 static int add_inode(struct bch_fs *c, struct inode_walker *w,
699 struct bkey_s_c inode)
700 {
701 struct bch_inode_unpacked u;
702
703 BUG_ON(bch2_inode_unpack(inode, &u));
704
705 return darray_push(&w->inodes, ((struct inode_walker_entry) {
706 .inode = u,
707 .snapshot = inode.k->p.snapshot,
708 }));
709 }
710
get_inodes_all_snapshots(struct btree_trans * trans,struct inode_walker * w,u64 inum)711 static int get_inodes_all_snapshots(struct btree_trans *trans,
712 struct inode_walker *w, u64 inum)
713 {
714 struct bch_fs *c = trans->c;
715 struct btree_iter iter;
716 struct bkey_s_c k;
717 int ret;
718
719 /*
720 * We no longer have inodes for w->last_pos; clear this to avoid
721 * screwing up check_i_sectors/check_subdir_count if we take a
722 * transaction restart here:
723 */
724 w->have_inodes = false;
725 w->recalculate_sums = false;
726 w->inodes.nr = 0;
727
728 for_each_btree_key_norestart(trans, iter, BTREE_ID_inodes, POS(0, inum),
729 BTREE_ITER_all_snapshots, k, ret) {
730 if (k.k->p.offset != inum)
731 break;
732
733 if (bkey_is_inode(k.k))
734 add_inode(c, w, k);
735 }
736 bch2_trans_iter_exit(trans, &iter);
737
738 if (ret)
739 return ret;
740
741 w->first_this_inode = true;
742 w->have_inodes = true;
743 return 0;
744 }
745
746 static struct inode_walker_entry *
lookup_inode_for_snapshot(struct bch_fs * c,struct inode_walker * w,struct bkey_s_c k)747 lookup_inode_for_snapshot(struct bch_fs *c, struct inode_walker *w, struct bkey_s_c k)
748 {
749 bool is_whiteout = k.k->type == KEY_TYPE_whiteout;
750
751 struct inode_walker_entry *i;
752 __darray_for_each(w->inodes, i)
753 if (bch2_snapshot_is_ancestor(c, k.k->p.snapshot, i->snapshot))
754 goto found;
755
756 return NULL;
757 found:
758 BUG_ON(k.k->p.snapshot > i->snapshot);
759
760 if (k.k->p.snapshot != i->snapshot && !is_whiteout) {
761 struct inode_walker_entry new = *i;
762
763 new.snapshot = k.k->p.snapshot;
764 new.count = 0;
765
766 struct printbuf buf = PRINTBUF;
767 bch2_bkey_val_to_text(&buf, c, k);
768
769 bch_info(c, "have key for inode %llu:%u but have inode in ancestor snapshot %u\n"
770 "unexpected because we should always update the inode when we update a key in that inode\n"
771 "%s",
772 w->last_pos.inode, k.k->p.snapshot, i->snapshot, buf.buf);
773 printbuf_exit(&buf);
774
775 while (i > w->inodes.data && i[-1].snapshot > k.k->p.snapshot)
776 --i;
777
778 size_t pos = i - w->inodes.data;
779 int ret = darray_insert_item(&w->inodes, pos, new);
780 if (ret)
781 return ERR_PTR(ret);
782
783 i = w->inodes.data + pos;
784 }
785
786 return i;
787 }
788
walk_inode(struct btree_trans * trans,struct inode_walker * w,struct bkey_s_c k)789 static struct inode_walker_entry *walk_inode(struct btree_trans *trans,
790 struct inode_walker *w,
791 struct bkey_s_c k)
792 {
793 if (w->last_pos.inode != k.k->p.inode) {
794 int ret = get_inodes_all_snapshots(trans, w, k.k->p.inode);
795 if (ret)
796 return ERR_PTR(ret);
797 }
798
799 w->last_pos = k.k->p;
800
801 return lookup_inode_for_snapshot(trans->c, w, k);
802 }
803
get_visible_inodes(struct btree_trans * trans,struct inode_walker * w,struct snapshots_seen * s,u64 inum)804 static int get_visible_inodes(struct btree_trans *trans,
805 struct inode_walker *w,
806 struct snapshots_seen *s,
807 u64 inum)
808 {
809 struct bch_fs *c = trans->c;
810 struct btree_iter iter;
811 struct bkey_s_c k;
812 int ret;
813
814 w->inodes.nr = 0;
815
816 for_each_btree_key_norestart(trans, iter, BTREE_ID_inodes, POS(0, inum),
817 BTREE_ITER_all_snapshots, k, ret) {
818 if (k.k->p.offset != inum)
819 break;
820
821 if (!ref_visible(c, s, s->pos.snapshot, k.k->p.snapshot))
822 continue;
823
824 if (bkey_is_inode(k.k))
825 add_inode(c, w, k);
826
827 if (k.k->p.snapshot >= s->pos.snapshot)
828 break;
829 }
830 bch2_trans_iter_exit(trans, &iter);
831
832 return ret;
833 }
834
hash_redo_key(struct btree_trans * trans,const struct bch_hash_desc desc,struct bch_hash_info * hash_info,struct btree_iter * k_iter,struct bkey_s_c k)835 static int hash_redo_key(struct btree_trans *trans,
836 const struct bch_hash_desc desc,
837 struct bch_hash_info *hash_info,
838 struct btree_iter *k_iter, struct bkey_s_c k)
839 {
840 struct bkey_i *delete;
841 struct bkey_i *tmp;
842
843 delete = bch2_trans_kmalloc(trans, sizeof(*delete));
844 if (IS_ERR(delete))
845 return PTR_ERR(delete);
846
847 tmp = bch2_bkey_make_mut_noupdate(trans, k);
848 if (IS_ERR(tmp))
849 return PTR_ERR(tmp);
850
851 bkey_init(&delete->k);
852 delete->k.p = k_iter->pos;
853 return bch2_btree_iter_traverse(k_iter) ?:
854 bch2_trans_update(trans, k_iter, delete, 0) ?:
855 bch2_hash_set_in_snapshot(trans, desc, hash_info,
856 (subvol_inum) { 0, k.k->p.inode },
857 k.k->p.snapshot, tmp,
858 STR_HASH_must_create|
859 BTREE_UPDATE_internal_snapshot_node) ?:
860 bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc);
861 }
862
hash_check_key(struct btree_trans * trans,const struct bch_hash_desc desc,struct bch_hash_info * hash_info,struct btree_iter * k_iter,struct bkey_s_c hash_k)863 static int hash_check_key(struct btree_trans *trans,
864 const struct bch_hash_desc desc,
865 struct bch_hash_info *hash_info,
866 struct btree_iter *k_iter, struct bkey_s_c hash_k)
867 {
868 struct bch_fs *c = trans->c;
869 struct btree_iter iter = { NULL };
870 struct printbuf buf = PRINTBUF;
871 struct bkey_s_c k;
872 u64 hash;
873 int ret = 0;
874
875 if (hash_k.k->type != desc.key_type)
876 return 0;
877
878 hash = desc.hash_bkey(hash_info, hash_k);
879
880 if (likely(hash == hash_k.k->p.offset))
881 return 0;
882
883 if (hash_k.k->p.offset < hash)
884 goto bad_hash;
885
886 for_each_btree_key_norestart(trans, iter, desc.btree_id,
887 SPOS(hash_k.k->p.inode, hash, hash_k.k->p.snapshot),
888 BTREE_ITER_slots, k, ret) {
889 if (bkey_eq(k.k->p, hash_k.k->p))
890 break;
891
892 if (fsck_err_on(k.k->type == desc.key_type &&
893 !desc.cmp_bkey(k, hash_k),
894 trans, hash_table_key_duplicate,
895 "duplicate hash table keys:\n%s",
896 (printbuf_reset(&buf),
897 bch2_bkey_val_to_text(&buf, c, hash_k),
898 buf.buf))) {
899 ret = bch2_hash_delete_at(trans, desc, hash_info, k_iter, 0) ?: 1;
900 break;
901 }
902
903 if (bkey_deleted(k.k)) {
904 bch2_trans_iter_exit(trans, &iter);
905 goto bad_hash;
906 }
907 }
908 out:
909 bch2_trans_iter_exit(trans, &iter);
910 printbuf_exit(&buf);
911 return ret;
912 bad_hash:
913 if (fsck_err(trans, hash_table_key_wrong_offset,
914 "hash table key at wrong offset: btree %s inode %llu offset %llu, hashed to %llu\n%s",
915 bch2_btree_id_str(desc.btree_id), hash_k.k->p.inode, hash_k.k->p.offset, hash,
916 (printbuf_reset(&buf),
917 bch2_bkey_val_to_text(&buf, c, hash_k), buf.buf))) {
918 ret = hash_redo_key(trans, desc, hash_info, k_iter, hash_k);
919 bch_err_fn(c, ret);
920 if (ret)
921 return ret;
922 ret = -BCH_ERR_transaction_restart_nested;
923 }
924 fsck_err:
925 goto out;
926 }
927
dirent_get_by_pos(struct btree_trans * trans,struct btree_iter * iter,struct bpos pos)928 static struct bkey_s_c_dirent dirent_get_by_pos(struct btree_trans *trans,
929 struct btree_iter *iter,
930 struct bpos pos)
931 {
932 return bch2_bkey_get_iter_typed(trans, iter, BTREE_ID_dirents, pos, 0, dirent);
933 }
934
inode_get_dirent(struct btree_trans * trans,struct btree_iter * iter,struct bch_inode_unpacked * inode,u32 * snapshot)935 static struct bkey_s_c_dirent inode_get_dirent(struct btree_trans *trans,
936 struct btree_iter *iter,
937 struct bch_inode_unpacked *inode,
938 u32 *snapshot)
939 {
940 if (inode->bi_subvol) {
941 u64 inum;
942 int ret = subvol_lookup(trans, inode->bi_parent_subvol, snapshot, &inum);
943 if (ret)
944 return ((struct bkey_s_c_dirent) { .k = ERR_PTR(ret) });
945 }
946
947 return dirent_get_by_pos(trans, iter, SPOS(inode->bi_dir, inode->bi_dir_offset, *snapshot));
948 }
949
check_inode_deleted_list(struct btree_trans * trans,struct bpos p)950 static int check_inode_deleted_list(struct btree_trans *trans, struct bpos p)
951 {
952 struct btree_iter iter;
953 struct bkey_s_c k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_deleted_inodes, p, 0);
954 int ret = bkey_err(k) ?: k.k->type == KEY_TYPE_set;
955 bch2_trans_iter_exit(trans, &iter);
956 return ret;
957 }
958
check_inode_dirent_inode(struct btree_trans * trans,struct bch_inode_unpacked * inode,bool * write_inode)959 static int check_inode_dirent_inode(struct btree_trans *trans,
960 struct bch_inode_unpacked *inode,
961 bool *write_inode)
962 {
963 struct bch_fs *c = trans->c;
964 struct printbuf buf = PRINTBUF;
965
966 u32 inode_snapshot = inode->bi_snapshot;
967 struct btree_iter dirent_iter = {};
968 struct bkey_s_c_dirent d = inode_get_dirent(trans, &dirent_iter, inode, &inode_snapshot);
969 int ret = bkey_err(d);
970 if (ret && !bch2_err_matches(ret, ENOENT))
971 return ret;
972
973 if (fsck_err_on(ret,
974 trans, inode_points_to_missing_dirent,
975 "inode points to missing dirent\n%s",
976 (bch2_inode_unpacked_to_text(&buf, inode), buf.buf)) ||
977 fsck_err_on(!ret && dirent_points_to_inode_nowarn(d, inode),
978 trans, inode_points_to_wrong_dirent,
979 "%s",
980 (printbuf_reset(&buf),
981 dirent_inode_mismatch_msg(&buf, c, d, inode),
982 buf.buf))) {
983 /*
984 * We just clear the backpointer fields for now. If we find a
985 * dirent that points to this inode in check_dirents(), we'll
986 * update it then; then when we get to check_path() if the
987 * backpointer is still 0 we'll reattach it.
988 */
989 inode->bi_dir = 0;
990 inode->bi_dir_offset = 0;
991 inode->bi_flags &= ~BCH_INODE_backptr_untrusted;
992 *write_inode = true;
993 }
994
995 ret = 0;
996 fsck_err:
997 bch2_trans_iter_exit(trans, &dirent_iter);
998 printbuf_exit(&buf);
999 bch_err_fn(c, ret);
1000 return ret;
1001 }
1002
bch2_inode_is_open(struct bch_fs * c,struct bpos p)1003 static bool bch2_inode_is_open(struct bch_fs *c, struct bpos p)
1004 {
1005 subvol_inum inum = {
1006 .subvol = snapshot_t(c, p.snapshot)->subvol,
1007 .inum = p.offset,
1008 };
1009
1010 /* snapshot tree corruption, can't safely delete */
1011 if (!inum.subvol) {
1012 bch_warn_ratelimited(c, "%s(): snapshot %u has no subvol, unlinked but can't safely delete", __func__, p.snapshot);
1013 return true;
1014 }
1015
1016 return __bch2_inode_hash_find(c, inum) != NULL;
1017 }
1018
check_inode(struct btree_trans * trans,struct btree_iter * iter,struct bkey_s_c k,struct bch_inode_unpacked * prev,struct snapshots_seen * s,bool full)1019 static int check_inode(struct btree_trans *trans,
1020 struct btree_iter *iter,
1021 struct bkey_s_c k,
1022 struct bch_inode_unpacked *prev,
1023 struct snapshots_seen *s,
1024 bool full)
1025 {
1026 struct bch_fs *c = trans->c;
1027 struct bch_inode_unpacked u;
1028 bool do_update = false;
1029 int ret;
1030
1031 ret = bch2_check_key_has_snapshot(trans, iter, k);
1032 if (ret < 0)
1033 goto err;
1034 if (ret)
1035 return 0;
1036
1037 ret = snapshots_seen_update(c, s, iter->btree_id, k.k->p);
1038 if (ret)
1039 goto err;
1040
1041 if (!bkey_is_inode(k.k))
1042 return 0;
1043
1044 BUG_ON(bch2_inode_unpack(k, &u));
1045
1046 if (!full &&
1047 !(u.bi_flags & (BCH_INODE_i_size_dirty|
1048 BCH_INODE_i_sectors_dirty|
1049 BCH_INODE_unlinked)))
1050 return 0;
1051
1052 if (prev->bi_inum != u.bi_inum)
1053 *prev = u;
1054
1055 if (fsck_err_on(prev->bi_hash_seed != u.bi_hash_seed ||
1056 inode_d_type(prev) != inode_d_type(&u),
1057 trans, inode_snapshot_mismatch,
1058 "inodes in different snapshots don't match")) {
1059 bch_err(c, "repair not implemented yet");
1060 return -BCH_ERR_fsck_repair_unimplemented;
1061 }
1062
1063 if ((u.bi_flags & (BCH_INODE_i_size_dirty|BCH_INODE_unlinked)) &&
1064 bch2_key_has_snapshot_overwrites(trans, BTREE_ID_inodes, k.k->p)) {
1065 struct bpos new_min_pos;
1066
1067 ret = bch2_propagate_key_to_snapshot_leaves(trans, iter->btree_id, k, &new_min_pos);
1068 if (ret)
1069 goto err;
1070
1071 u.bi_flags &= ~BCH_INODE_i_size_dirty|BCH_INODE_unlinked;
1072
1073 ret = __bch2_fsck_write_inode(trans, &u, iter->pos.snapshot);
1074
1075 bch_err_msg(c, ret, "in fsck updating inode");
1076 if (ret)
1077 return ret;
1078
1079 if (!bpos_eq(new_min_pos, POS_MIN))
1080 bch2_btree_iter_set_pos(iter, bpos_predecessor(new_min_pos));
1081 return 0;
1082 }
1083
1084 if (u.bi_flags & BCH_INODE_unlinked) {
1085 if (!test_bit(BCH_FS_started, &c->flags)) {
1086 /*
1087 * If we're not in online fsck, don't delete unlinked
1088 * inodes, just make sure they're on the deleted list.
1089 *
1090 * They might be referred to by a logged operation -
1091 * i.e. we might have crashed in the middle of a
1092 * truncate on an unlinked but open file - so we want to
1093 * let the delete_dead_inodes kill it after resuming
1094 * logged ops.
1095 */
1096 ret = check_inode_deleted_list(trans, k.k->p);
1097 if (ret < 0)
1098 return ret;
1099
1100 fsck_err_on(!ret,
1101 trans, unlinked_inode_not_on_deleted_list,
1102 "inode %llu:%u unlinked, but not on deleted list",
1103 u.bi_inum, k.k->p.snapshot);
1104
1105 ret = bch2_btree_bit_mod_buffered(trans, BTREE_ID_deleted_inodes, k.k->p, 1);
1106 if (ret)
1107 goto err;
1108 } else {
1109 if (fsck_err_on(bch2_inode_is_open(c, k.k->p),
1110 trans, inode_unlinked_and_not_open,
1111 "inode %llu%u unlinked and not open",
1112 u.bi_inum, u.bi_snapshot)) {
1113 ret = bch2_inode_rm_snapshot(trans, u.bi_inum, iter->pos.snapshot);
1114 bch_err_msg(c, ret, "in fsck deleting inode");
1115 return ret;
1116 }
1117 }
1118 }
1119
1120 /* i_size_dirty is vestigal, since we now have logged ops for truncate * */
1121 if (u.bi_flags & BCH_INODE_i_size_dirty &&
1122 (!test_bit(BCH_FS_clean_recovery, &c->flags) ||
1123 fsck_err(trans, inode_i_size_dirty_but_clean,
1124 "filesystem marked clean, but inode %llu has i_size dirty",
1125 u.bi_inum))) {
1126 bch_verbose(c, "truncating inode %llu", u.bi_inum);
1127
1128 /*
1129 * XXX: need to truncate partial blocks too here - or ideally
1130 * just switch units to bytes and that issue goes away
1131 */
1132 ret = bch2_btree_delete_range_trans(trans, BTREE_ID_extents,
1133 SPOS(u.bi_inum, round_up(u.bi_size, block_bytes(c)) >> 9,
1134 iter->pos.snapshot),
1135 POS(u.bi_inum, U64_MAX),
1136 0, NULL);
1137 bch_err_msg(c, ret, "in fsck truncating inode");
1138 if (ret)
1139 return ret;
1140
1141 /*
1142 * We truncated without our normal sector accounting hook, just
1143 * make sure we recalculate it:
1144 */
1145 u.bi_flags |= BCH_INODE_i_sectors_dirty;
1146
1147 u.bi_flags &= ~BCH_INODE_i_size_dirty;
1148 do_update = true;
1149 }
1150
1151 /* i_sectors_dirty is vestigal, i_sectors is always updated transactionally */
1152 if (u.bi_flags & BCH_INODE_i_sectors_dirty &&
1153 (!test_bit(BCH_FS_clean_recovery, &c->flags) ||
1154 fsck_err(trans, inode_i_sectors_dirty_but_clean,
1155 "filesystem marked clean, but inode %llu has i_sectors dirty",
1156 u.bi_inum))) {
1157 s64 sectors;
1158
1159 bch_verbose(c, "recounting sectors for inode %llu",
1160 u.bi_inum);
1161
1162 sectors = bch2_count_inode_sectors(trans, u.bi_inum, iter->pos.snapshot);
1163 if (sectors < 0) {
1164 bch_err_msg(c, sectors, "in fsck recounting inode sectors");
1165 return sectors;
1166 }
1167
1168 u.bi_sectors = sectors;
1169 u.bi_flags &= ~BCH_INODE_i_sectors_dirty;
1170 do_update = true;
1171 }
1172
1173 if (u.bi_flags & BCH_INODE_backptr_untrusted) {
1174 u.bi_dir = 0;
1175 u.bi_dir_offset = 0;
1176 u.bi_flags &= ~BCH_INODE_backptr_untrusted;
1177 do_update = true;
1178 }
1179
1180 if (u.bi_dir || u.bi_dir_offset) {
1181 ret = check_inode_dirent_inode(trans, &u, &do_update);
1182 if (ret)
1183 goto err;
1184 }
1185
1186 if (fsck_err_on(u.bi_parent_subvol &&
1187 (u.bi_subvol == 0 ||
1188 u.bi_subvol == BCACHEFS_ROOT_SUBVOL),
1189 trans, inode_bi_parent_nonzero,
1190 "inode %llu:%u has subvol %u but nonzero parent subvol %u",
1191 u.bi_inum, k.k->p.snapshot, u.bi_subvol, u.bi_parent_subvol)) {
1192 u.bi_parent_subvol = 0;
1193 do_update = true;
1194 }
1195
1196 if (u.bi_subvol) {
1197 struct bch_subvolume s;
1198
1199 ret = bch2_subvolume_get(trans, u.bi_subvol, false, 0, &s);
1200 if (ret && !bch2_err_matches(ret, ENOENT))
1201 goto err;
1202
1203 if (ret && (c->sb.btrees_lost_data & BIT_ULL(BTREE_ID_subvolumes))) {
1204 ret = reconstruct_subvol(trans, k.k->p.snapshot, u.bi_subvol, u.bi_inum);
1205 goto do_update;
1206 }
1207
1208 if (fsck_err_on(ret,
1209 trans, inode_bi_subvol_missing,
1210 "inode %llu:%u bi_subvol points to missing subvolume %u",
1211 u.bi_inum, k.k->p.snapshot, u.bi_subvol) ||
1212 fsck_err_on(le64_to_cpu(s.inode) != u.bi_inum ||
1213 !bch2_snapshot_is_ancestor(c, le32_to_cpu(s.snapshot),
1214 k.k->p.snapshot),
1215 trans, inode_bi_subvol_wrong,
1216 "inode %llu:%u points to subvol %u, but subvol points to %llu:%u",
1217 u.bi_inum, k.k->p.snapshot, u.bi_subvol,
1218 le64_to_cpu(s.inode),
1219 le32_to_cpu(s.snapshot))) {
1220 u.bi_subvol = 0;
1221 u.bi_parent_subvol = 0;
1222 do_update = true;
1223 }
1224 }
1225 do_update:
1226 if (do_update) {
1227 ret = __bch2_fsck_write_inode(trans, &u, iter->pos.snapshot);
1228 bch_err_msg(c, ret, "in fsck updating inode");
1229 if (ret)
1230 return ret;
1231 }
1232 err:
1233 fsck_err:
1234 bch_err_fn(c, ret);
1235 return ret;
1236 }
1237
bch2_check_inodes(struct bch_fs * c)1238 int bch2_check_inodes(struct bch_fs *c)
1239 {
1240 bool full = c->opts.fsck;
1241 struct bch_inode_unpacked prev = { 0 };
1242 struct snapshots_seen s;
1243
1244 snapshots_seen_init(&s);
1245
1246 int ret = bch2_trans_run(c,
1247 for_each_btree_key_commit(trans, iter, BTREE_ID_inodes,
1248 POS_MIN,
1249 BTREE_ITER_prefetch|BTREE_ITER_all_snapshots, k,
1250 NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
1251 check_inode(trans, &iter, k, &prev, &s, full)));
1252
1253 snapshots_seen_exit(&s);
1254 bch_err_fn(c, ret);
1255 return ret;
1256 }
1257
btree_matches_i_mode(enum btree_id btree,unsigned mode)1258 static inline bool btree_matches_i_mode(enum btree_id btree, unsigned mode)
1259 {
1260 switch (btree) {
1261 case BTREE_ID_extents:
1262 return S_ISREG(mode) || S_ISLNK(mode);
1263 case BTREE_ID_dirents:
1264 return S_ISDIR(mode);
1265 case BTREE_ID_xattrs:
1266 return true;
1267 default:
1268 BUG();
1269 }
1270 }
1271
check_key_has_inode(struct btree_trans * trans,struct btree_iter * iter,struct inode_walker * inode,struct inode_walker_entry * i,struct bkey_s_c k)1272 static int check_key_has_inode(struct btree_trans *trans,
1273 struct btree_iter *iter,
1274 struct inode_walker *inode,
1275 struct inode_walker_entry *i,
1276 struct bkey_s_c k)
1277 {
1278 struct bch_fs *c = trans->c;
1279 struct printbuf buf = PRINTBUF;
1280 int ret = PTR_ERR_OR_ZERO(i);
1281 if (ret)
1282 return ret;
1283
1284 if (k.k->type == KEY_TYPE_whiteout)
1285 goto out;
1286
1287 if (!i && (c->sb.btrees_lost_data & BIT_ULL(BTREE_ID_inodes))) {
1288 ret = reconstruct_inode(trans, iter->btree_id, k.k->p.snapshot, k.k->p.inode) ?:
1289 bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc);
1290 if (ret)
1291 goto err;
1292
1293 inode->last_pos.inode--;
1294 ret = -BCH_ERR_transaction_restart_nested;
1295 goto err;
1296 }
1297
1298 if (fsck_err_on(!i,
1299 trans, key_in_missing_inode,
1300 "key in missing inode:\n %s",
1301 (printbuf_reset(&buf),
1302 bch2_bkey_val_to_text(&buf, c, k), buf.buf)))
1303 goto delete;
1304
1305 if (fsck_err_on(i && !btree_matches_i_mode(iter->btree_id, i->inode.bi_mode),
1306 trans, key_in_wrong_inode_type,
1307 "key for wrong inode mode %o:\n %s",
1308 i->inode.bi_mode,
1309 (printbuf_reset(&buf),
1310 bch2_bkey_val_to_text(&buf, c, k), buf.buf)))
1311 goto delete;
1312 out:
1313 err:
1314 fsck_err:
1315 printbuf_exit(&buf);
1316 bch_err_fn(c, ret);
1317 return ret;
1318 delete:
1319 ret = bch2_btree_delete_at(trans, iter, BTREE_UPDATE_internal_snapshot_node);
1320 goto out;
1321 }
1322
check_i_sectors_notnested(struct btree_trans * trans,struct inode_walker * w)1323 static int check_i_sectors_notnested(struct btree_trans *trans, struct inode_walker *w)
1324 {
1325 struct bch_fs *c = trans->c;
1326 int ret = 0;
1327 s64 count2;
1328
1329 darray_for_each(w->inodes, i) {
1330 if (i->inode.bi_sectors == i->count)
1331 continue;
1332
1333 count2 = bch2_count_inode_sectors(trans, w->last_pos.inode, i->snapshot);
1334
1335 if (w->recalculate_sums)
1336 i->count = count2;
1337
1338 if (i->count != count2) {
1339 bch_err_ratelimited(c, "fsck counted i_sectors wrong for inode %llu:%u: got %llu should be %llu",
1340 w->last_pos.inode, i->snapshot, i->count, count2);
1341 return -BCH_ERR_internal_fsck_err;
1342 }
1343
1344 if (fsck_err_on(!(i->inode.bi_flags & BCH_INODE_i_sectors_dirty),
1345 trans, inode_i_sectors_wrong,
1346 "inode %llu:%u has incorrect i_sectors: got %llu, should be %llu",
1347 w->last_pos.inode, i->snapshot,
1348 i->inode.bi_sectors, i->count)) {
1349 i->inode.bi_sectors = i->count;
1350 ret = bch2_fsck_write_inode(trans, &i->inode, i->snapshot);
1351 if (ret)
1352 break;
1353 }
1354 }
1355 fsck_err:
1356 bch_err_fn(c, ret);
1357 return ret;
1358 }
1359
check_i_sectors(struct btree_trans * trans,struct inode_walker * w)1360 static int check_i_sectors(struct btree_trans *trans, struct inode_walker *w)
1361 {
1362 u32 restart_count = trans->restart_count;
1363 return check_i_sectors_notnested(trans, w) ?:
1364 trans_was_restarted(trans, restart_count);
1365 }
1366
1367 struct extent_end {
1368 u32 snapshot;
1369 u64 offset;
1370 struct snapshots_seen seen;
1371 };
1372
1373 struct extent_ends {
1374 struct bpos last_pos;
1375 DARRAY(struct extent_end) e;
1376 };
1377
extent_ends_reset(struct extent_ends * extent_ends)1378 static void extent_ends_reset(struct extent_ends *extent_ends)
1379 {
1380 darray_for_each(extent_ends->e, i)
1381 snapshots_seen_exit(&i->seen);
1382 extent_ends->e.nr = 0;
1383 }
1384
extent_ends_exit(struct extent_ends * extent_ends)1385 static void extent_ends_exit(struct extent_ends *extent_ends)
1386 {
1387 extent_ends_reset(extent_ends);
1388 darray_exit(&extent_ends->e);
1389 }
1390
extent_ends_init(struct extent_ends * extent_ends)1391 static void extent_ends_init(struct extent_ends *extent_ends)
1392 {
1393 memset(extent_ends, 0, sizeof(*extent_ends));
1394 }
1395
extent_ends_at(struct bch_fs * c,struct extent_ends * extent_ends,struct snapshots_seen * seen,struct bkey_s_c k)1396 static int extent_ends_at(struct bch_fs *c,
1397 struct extent_ends *extent_ends,
1398 struct snapshots_seen *seen,
1399 struct bkey_s_c k)
1400 {
1401 struct extent_end *i, n = (struct extent_end) {
1402 .offset = k.k->p.offset,
1403 .snapshot = k.k->p.snapshot,
1404 .seen = *seen,
1405 };
1406
1407 n.seen.ids.data = kmemdup(seen->ids.data,
1408 sizeof(seen->ids.data[0]) * seen->ids.size,
1409 GFP_KERNEL);
1410 if (!n.seen.ids.data)
1411 return -BCH_ERR_ENOMEM_fsck_extent_ends_at;
1412
1413 __darray_for_each(extent_ends->e, i) {
1414 if (i->snapshot == k.k->p.snapshot) {
1415 snapshots_seen_exit(&i->seen);
1416 *i = n;
1417 return 0;
1418 }
1419
1420 if (i->snapshot >= k.k->p.snapshot)
1421 break;
1422 }
1423
1424 return darray_insert_item(&extent_ends->e, i - extent_ends->e.data, n);
1425 }
1426
overlapping_extents_found(struct btree_trans * trans,enum btree_id btree,struct bpos pos1,struct snapshots_seen * pos1_seen,struct bkey pos2,bool * fixed,struct extent_end * extent_end)1427 static int overlapping_extents_found(struct btree_trans *trans,
1428 enum btree_id btree,
1429 struct bpos pos1, struct snapshots_seen *pos1_seen,
1430 struct bkey pos2,
1431 bool *fixed,
1432 struct extent_end *extent_end)
1433 {
1434 struct bch_fs *c = trans->c;
1435 struct printbuf buf = PRINTBUF;
1436 struct btree_iter iter1, iter2 = { NULL };
1437 struct bkey_s_c k1, k2;
1438 int ret;
1439
1440 BUG_ON(bkey_le(pos1, bkey_start_pos(&pos2)));
1441
1442 bch2_trans_iter_init(trans, &iter1, btree, pos1,
1443 BTREE_ITER_all_snapshots|
1444 BTREE_ITER_not_extents);
1445 k1 = bch2_btree_iter_peek_upto(&iter1, POS(pos1.inode, U64_MAX));
1446 ret = bkey_err(k1);
1447 if (ret)
1448 goto err;
1449
1450 prt_str(&buf, "\n ");
1451 bch2_bkey_val_to_text(&buf, c, k1);
1452
1453 if (!bpos_eq(pos1, k1.k->p)) {
1454 prt_str(&buf, "\n wanted\n ");
1455 bch2_bpos_to_text(&buf, pos1);
1456 prt_str(&buf, "\n ");
1457 bch2_bkey_to_text(&buf, &pos2);
1458
1459 bch_err(c, "%s: error finding first overlapping extent when repairing, got%s",
1460 __func__, buf.buf);
1461 ret = -BCH_ERR_internal_fsck_err;
1462 goto err;
1463 }
1464
1465 bch2_trans_copy_iter(&iter2, &iter1);
1466
1467 while (1) {
1468 bch2_btree_iter_advance(&iter2);
1469
1470 k2 = bch2_btree_iter_peek_upto(&iter2, POS(pos1.inode, U64_MAX));
1471 ret = bkey_err(k2);
1472 if (ret)
1473 goto err;
1474
1475 if (bpos_ge(k2.k->p, pos2.p))
1476 break;
1477 }
1478
1479 prt_str(&buf, "\n ");
1480 bch2_bkey_val_to_text(&buf, c, k2);
1481
1482 if (bpos_gt(k2.k->p, pos2.p) ||
1483 pos2.size != k2.k->size) {
1484 bch_err(c, "%s: error finding seconding overlapping extent when repairing%s",
1485 __func__, buf.buf);
1486 ret = -BCH_ERR_internal_fsck_err;
1487 goto err;
1488 }
1489
1490 prt_printf(&buf, "\n overwriting %s extent",
1491 pos1.snapshot >= pos2.p.snapshot ? "first" : "second");
1492
1493 if (fsck_err(trans, extent_overlapping,
1494 "overlapping extents%s", buf.buf)) {
1495 struct btree_iter *old_iter = &iter1;
1496 struct disk_reservation res = { 0 };
1497
1498 if (pos1.snapshot < pos2.p.snapshot) {
1499 old_iter = &iter2;
1500 swap(k1, k2);
1501 }
1502
1503 trans->extra_disk_res += bch2_bkey_sectors_compressed(k2);
1504
1505 ret = bch2_trans_update_extent_overwrite(trans, old_iter,
1506 BTREE_UPDATE_internal_snapshot_node,
1507 k1, k2) ?:
1508 bch2_trans_commit(trans, &res, NULL, BCH_TRANS_COMMIT_no_enospc);
1509 bch2_disk_reservation_put(c, &res);
1510
1511 if (ret)
1512 goto err;
1513
1514 *fixed = true;
1515
1516 if (pos1.snapshot == pos2.p.snapshot) {
1517 /*
1518 * We overwrote the first extent, and did the overwrite
1519 * in the same snapshot:
1520 */
1521 extent_end->offset = bkey_start_offset(&pos2);
1522 } else if (pos1.snapshot > pos2.p.snapshot) {
1523 /*
1524 * We overwrote the first extent in pos2's snapshot:
1525 */
1526 ret = snapshots_seen_add_inorder(c, pos1_seen, pos2.p.snapshot);
1527 } else {
1528 /*
1529 * We overwrote the second extent - restart
1530 * check_extent() from the top:
1531 */
1532 ret = -BCH_ERR_transaction_restart_nested;
1533 }
1534 }
1535 fsck_err:
1536 err:
1537 bch2_trans_iter_exit(trans, &iter2);
1538 bch2_trans_iter_exit(trans, &iter1);
1539 printbuf_exit(&buf);
1540 return ret;
1541 }
1542
check_overlapping_extents(struct btree_trans * trans,struct snapshots_seen * seen,struct extent_ends * extent_ends,struct bkey_s_c k,struct btree_iter * iter,bool * fixed)1543 static int check_overlapping_extents(struct btree_trans *trans,
1544 struct snapshots_seen *seen,
1545 struct extent_ends *extent_ends,
1546 struct bkey_s_c k,
1547 struct btree_iter *iter,
1548 bool *fixed)
1549 {
1550 struct bch_fs *c = trans->c;
1551 int ret = 0;
1552
1553 /* transaction restart, running again */
1554 if (bpos_eq(extent_ends->last_pos, k.k->p))
1555 return 0;
1556
1557 if (extent_ends->last_pos.inode != k.k->p.inode)
1558 extent_ends_reset(extent_ends);
1559
1560 darray_for_each(extent_ends->e, i) {
1561 if (i->offset <= bkey_start_offset(k.k))
1562 continue;
1563
1564 if (!ref_visible2(c,
1565 k.k->p.snapshot, seen,
1566 i->snapshot, &i->seen))
1567 continue;
1568
1569 ret = overlapping_extents_found(trans, iter->btree_id,
1570 SPOS(iter->pos.inode,
1571 i->offset,
1572 i->snapshot),
1573 &i->seen,
1574 *k.k, fixed, i);
1575 if (ret)
1576 goto err;
1577 }
1578
1579 extent_ends->last_pos = k.k->p;
1580 err:
1581 return ret;
1582 }
1583
check_extent_overbig(struct btree_trans * trans,struct btree_iter * iter,struct bkey_s_c k)1584 static int check_extent_overbig(struct btree_trans *trans, struct btree_iter *iter,
1585 struct bkey_s_c k)
1586 {
1587 struct bch_fs *c = trans->c;
1588 struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1589 struct bch_extent_crc_unpacked crc;
1590 const union bch_extent_entry *i;
1591 unsigned encoded_extent_max_sectors = c->opts.encoded_extent_max >> 9;
1592
1593 bkey_for_each_crc(k.k, ptrs, crc, i)
1594 if (crc_is_encoded(crc) &&
1595 crc.uncompressed_size > encoded_extent_max_sectors) {
1596 struct printbuf buf = PRINTBUF;
1597
1598 bch2_bkey_val_to_text(&buf, c, k);
1599 bch_err(c, "overbig encoded extent, please report this:\n %s", buf.buf);
1600 printbuf_exit(&buf);
1601 }
1602
1603 return 0;
1604 }
1605
check_extent(struct btree_trans * trans,struct btree_iter * iter,struct bkey_s_c k,struct inode_walker * inode,struct snapshots_seen * s,struct extent_ends * extent_ends,struct disk_reservation * res)1606 static int check_extent(struct btree_trans *trans, struct btree_iter *iter,
1607 struct bkey_s_c k,
1608 struct inode_walker *inode,
1609 struct snapshots_seen *s,
1610 struct extent_ends *extent_ends,
1611 struct disk_reservation *res)
1612 {
1613 struct bch_fs *c = trans->c;
1614 struct printbuf buf = PRINTBUF;
1615 int ret = 0;
1616
1617 ret = bch2_check_key_has_snapshot(trans, iter, k);
1618 if (ret) {
1619 ret = ret < 0 ? ret : 0;
1620 goto out;
1621 }
1622
1623 if (inode->last_pos.inode != k.k->p.inode && inode->have_inodes) {
1624 ret = check_i_sectors(trans, inode);
1625 if (ret)
1626 goto err;
1627 }
1628
1629 ret = snapshots_seen_update(c, s, iter->btree_id, k.k->p);
1630 if (ret)
1631 goto err;
1632
1633 struct inode_walker_entry *extent_i = walk_inode(trans, inode, k);
1634 ret = PTR_ERR_OR_ZERO(extent_i);
1635 if (ret)
1636 goto err;
1637
1638 ret = check_key_has_inode(trans, iter, inode, extent_i, k);
1639 if (ret)
1640 goto err;
1641
1642 if (k.k->type != KEY_TYPE_whiteout) {
1643 ret = check_overlapping_extents(trans, s, extent_ends, k, iter,
1644 &inode->recalculate_sums);
1645 if (ret)
1646 goto err;
1647
1648 /*
1649 * Check inodes in reverse order, from oldest snapshots to
1650 * newest, starting from the inode that matches this extent's
1651 * snapshot. If we didn't have one, iterate over all inodes:
1652 */
1653 for (struct inode_walker_entry *i = extent_i ?: &darray_last(inode->inodes);
1654 inode->inodes.data && i >= inode->inodes.data;
1655 --i) {
1656 if (i->snapshot > k.k->p.snapshot ||
1657 !key_visible_in_snapshot(c, s, i->snapshot, k.k->p.snapshot))
1658 continue;
1659
1660 if (fsck_err_on(!(i->inode.bi_flags & BCH_INODE_i_size_dirty) &&
1661 k.k->p.offset > round_up(i->inode.bi_size, block_bytes(c)) >> 9 &&
1662 !bkey_extent_is_reservation(k),
1663 trans, extent_past_end_of_inode,
1664 "extent type past end of inode %llu:%u, i_size %llu\n %s",
1665 i->inode.bi_inum, i->snapshot, i->inode.bi_size,
1666 (bch2_bkey_val_to_text(&buf, c, k), buf.buf))) {
1667 struct btree_iter iter2;
1668
1669 bch2_trans_copy_iter(&iter2, iter);
1670 bch2_btree_iter_set_snapshot(&iter2, i->snapshot);
1671 ret = bch2_btree_iter_traverse(&iter2) ?:
1672 bch2_btree_delete_at(trans, &iter2,
1673 BTREE_UPDATE_internal_snapshot_node);
1674 bch2_trans_iter_exit(trans, &iter2);
1675 if (ret)
1676 goto err;
1677
1678 iter->k.type = KEY_TYPE_whiteout;
1679 break;
1680 }
1681 }
1682 }
1683
1684 ret = bch2_trans_commit(trans, res, NULL, BCH_TRANS_COMMIT_no_enospc);
1685 if (ret)
1686 goto err;
1687
1688 if (bkey_extent_is_allocation(k.k)) {
1689 for (struct inode_walker_entry *i = extent_i ?: &darray_last(inode->inodes);
1690 inode->inodes.data && i >= inode->inodes.data;
1691 --i) {
1692 if (i->snapshot > k.k->p.snapshot ||
1693 !key_visible_in_snapshot(c, s, i->snapshot, k.k->p.snapshot))
1694 continue;
1695
1696 i->count += k.k->size;
1697 }
1698 }
1699
1700 if (k.k->type != KEY_TYPE_whiteout) {
1701 ret = extent_ends_at(c, extent_ends, s, k);
1702 if (ret)
1703 goto err;
1704 }
1705 out:
1706 err:
1707 fsck_err:
1708 printbuf_exit(&buf);
1709 bch_err_fn(c, ret);
1710 return ret;
1711 }
1712
1713 /*
1714 * Walk extents: verify that extents have a corresponding S_ISREG inode, and
1715 * that i_size an i_sectors are consistent
1716 */
bch2_check_extents(struct bch_fs * c)1717 int bch2_check_extents(struct bch_fs *c)
1718 {
1719 struct inode_walker w = inode_walker_init();
1720 struct snapshots_seen s;
1721 struct extent_ends extent_ends;
1722 struct disk_reservation res = { 0 };
1723
1724 snapshots_seen_init(&s);
1725 extent_ends_init(&extent_ends);
1726
1727 int ret = bch2_trans_run(c,
1728 for_each_btree_key(trans, iter, BTREE_ID_extents,
1729 POS(BCACHEFS_ROOT_INO, 0),
1730 BTREE_ITER_prefetch|BTREE_ITER_all_snapshots, k, ({
1731 bch2_disk_reservation_put(c, &res);
1732 check_extent(trans, &iter, k, &w, &s, &extent_ends, &res) ?:
1733 check_extent_overbig(trans, &iter, k);
1734 })) ?:
1735 check_i_sectors_notnested(trans, &w));
1736
1737 bch2_disk_reservation_put(c, &res);
1738 extent_ends_exit(&extent_ends);
1739 inode_walker_exit(&w);
1740 snapshots_seen_exit(&s);
1741
1742 bch_err_fn(c, ret);
1743 return ret;
1744 }
1745
bch2_check_indirect_extents(struct bch_fs * c)1746 int bch2_check_indirect_extents(struct bch_fs *c)
1747 {
1748 struct disk_reservation res = { 0 };
1749
1750 int ret = bch2_trans_run(c,
1751 for_each_btree_key_commit(trans, iter, BTREE_ID_reflink,
1752 POS_MIN,
1753 BTREE_ITER_prefetch, k,
1754 &res, NULL,
1755 BCH_TRANS_COMMIT_no_enospc, ({
1756 bch2_disk_reservation_put(c, &res);
1757 check_extent_overbig(trans, &iter, k);
1758 })));
1759
1760 bch2_disk_reservation_put(c, &res);
1761 bch_err_fn(c, ret);
1762 return ret;
1763 }
1764
check_subdir_count_notnested(struct btree_trans * trans,struct inode_walker * w)1765 static int check_subdir_count_notnested(struct btree_trans *trans, struct inode_walker *w)
1766 {
1767 struct bch_fs *c = trans->c;
1768 int ret = 0;
1769 s64 count2;
1770
1771 darray_for_each(w->inodes, i) {
1772 if (i->inode.bi_nlink == i->count)
1773 continue;
1774
1775 count2 = bch2_count_subdirs(trans, w->last_pos.inode, i->snapshot);
1776 if (count2 < 0)
1777 return count2;
1778
1779 if (i->count != count2) {
1780 bch_err_ratelimited(c, "fsck counted subdirectories wrong for inum %llu:%u: got %llu should be %llu",
1781 w->last_pos.inode, i->snapshot, i->count, count2);
1782 i->count = count2;
1783 if (i->inode.bi_nlink == i->count)
1784 continue;
1785 }
1786
1787 if (fsck_err_on(i->inode.bi_nlink != i->count,
1788 trans, inode_dir_wrong_nlink,
1789 "directory %llu:%u with wrong i_nlink: got %u, should be %llu",
1790 w->last_pos.inode, i->snapshot, i->inode.bi_nlink, i->count)) {
1791 i->inode.bi_nlink = i->count;
1792 ret = bch2_fsck_write_inode(trans, &i->inode, i->snapshot);
1793 if (ret)
1794 break;
1795 }
1796 }
1797 fsck_err:
1798 bch_err_fn(c, ret);
1799 return ret;
1800 }
1801
check_subdir_count(struct btree_trans * trans,struct inode_walker * w)1802 static int check_subdir_count(struct btree_trans *trans, struct inode_walker *w)
1803 {
1804 u32 restart_count = trans->restart_count;
1805 return check_subdir_count_notnested(trans, w) ?:
1806 trans_was_restarted(trans, restart_count);
1807 }
1808
1809 noinline_for_stack
check_dirent_inode_dirent(struct btree_trans * trans,struct btree_iter * iter,struct bkey_s_c_dirent d,struct bch_inode_unpacked * target,u32 target_snapshot)1810 static int check_dirent_inode_dirent(struct btree_trans *trans,
1811 struct btree_iter *iter,
1812 struct bkey_s_c_dirent d,
1813 struct bch_inode_unpacked *target,
1814 u32 target_snapshot)
1815 {
1816 struct bch_fs *c = trans->c;
1817 struct printbuf buf = PRINTBUF;
1818 struct btree_iter bp_iter = { NULL };
1819 int ret = 0;
1820
1821 if (inode_points_to_dirent(target, d))
1822 return 0;
1823
1824 if (bch2_inode_should_have_bp(target) &&
1825 !fsck_err(trans, inode_wrong_backpointer,
1826 "dirent points to inode that does not point back:\n %s",
1827 (bch2_bkey_val_to_text(&buf, c, d.s_c),
1828 prt_printf(&buf, "\n "),
1829 bch2_inode_unpacked_to_text(&buf, target),
1830 buf.buf)))
1831 goto err;
1832
1833 if (!target->bi_dir &&
1834 !target->bi_dir_offset) {
1835 target->bi_dir = d.k->p.inode;
1836 target->bi_dir_offset = d.k->p.offset;
1837 return __bch2_fsck_write_inode(trans, target, target_snapshot);
1838 }
1839
1840 struct bkey_s_c_dirent bp_dirent = dirent_get_by_pos(trans, &bp_iter,
1841 SPOS(target->bi_dir, target->bi_dir_offset, target_snapshot));
1842 ret = bkey_err(bp_dirent);
1843 if (ret && !bch2_err_matches(ret, ENOENT))
1844 goto err;
1845
1846 bool backpointer_exists = !ret;
1847 ret = 0;
1848
1849 if (fsck_err_on(!backpointer_exists,
1850 trans, inode_wrong_backpointer,
1851 "inode %llu:%u has wrong backpointer:\n"
1852 "got %llu:%llu\n"
1853 "should be %llu:%llu",
1854 target->bi_inum, target_snapshot,
1855 target->bi_dir,
1856 target->bi_dir_offset,
1857 d.k->p.inode,
1858 d.k->p.offset)) {
1859 target->bi_dir = d.k->p.inode;
1860 target->bi_dir_offset = d.k->p.offset;
1861 ret = __bch2_fsck_write_inode(trans, target, target_snapshot);
1862 goto out;
1863 }
1864
1865 bch2_bkey_val_to_text(&buf, c, d.s_c);
1866 prt_newline(&buf);
1867 if (backpointer_exists)
1868 bch2_bkey_val_to_text(&buf, c, bp_dirent.s_c);
1869
1870 if (fsck_err_on(backpointer_exists &&
1871 (S_ISDIR(target->bi_mode) ||
1872 target->bi_subvol),
1873 trans, inode_dir_multiple_links,
1874 "%s %llu:%u with multiple links\n%s",
1875 S_ISDIR(target->bi_mode) ? "directory" : "subvolume",
1876 target->bi_inum, target_snapshot, buf.buf)) {
1877 ret = __remove_dirent(trans, d.k->p);
1878 goto out;
1879 }
1880
1881 /*
1882 * hardlinked file with nlink 0:
1883 * We're just adjusting nlink here so check_nlinks() will pick
1884 * it up, it ignores inodes with nlink 0
1885 */
1886 if (fsck_err_on(backpointer_exists && !target->bi_nlink,
1887 trans, inode_multiple_links_but_nlink_0,
1888 "inode %llu:%u type %s has multiple links but i_nlink 0\n%s",
1889 target->bi_inum, target_snapshot, bch2_d_types[d.v->d_type], buf.buf)) {
1890 target->bi_nlink++;
1891 target->bi_flags &= ~BCH_INODE_unlinked;
1892 ret = __bch2_fsck_write_inode(trans, target, target_snapshot);
1893 if (ret)
1894 goto err;
1895 }
1896 out:
1897 err:
1898 fsck_err:
1899 bch2_trans_iter_exit(trans, &bp_iter);
1900 printbuf_exit(&buf);
1901 bch_err_fn(c, ret);
1902 return ret;
1903 }
1904
1905 noinline_for_stack
check_dirent_target(struct btree_trans * trans,struct btree_iter * iter,struct bkey_s_c_dirent d,struct bch_inode_unpacked * target,u32 target_snapshot)1906 static int check_dirent_target(struct btree_trans *trans,
1907 struct btree_iter *iter,
1908 struct bkey_s_c_dirent d,
1909 struct bch_inode_unpacked *target,
1910 u32 target_snapshot)
1911 {
1912 struct bch_fs *c = trans->c;
1913 struct bkey_i_dirent *n;
1914 struct printbuf buf = PRINTBUF;
1915 int ret = 0;
1916
1917 ret = check_dirent_inode_dirent(trans, iter, d, target, target_snapshot);
1918 if (ret)
1919 goto err;
1920
1921 if (fsck_err_on(d.v->d_type != inode_d_type(target),
1922 trans, dirent_d_type_wrong,
1923 "incorrect d_type: got %s, should be %s:\n%s",
1924 bch2_d_type_str(d.v->d_type),
1925 bch2_d_type_str(inode_d_type(target)),
1926 (printbuf_reset(&buf),
1927 bch2_bkey_val_to_text(&buf, c, d.s_c), buf.buf))) {
1928 n = bch2_trans_kmalloc(trans, bkey_bytes(d.k));
1929 ret = PTR_ERR_OR_ZERO(n);
1930 if (ret)
1931 goto err;
1932
1933 bkey_reassemble(&n->k_i, d.s_c);
1934 n->v.d_type = inode_d_type(target);
1935 if (n->v.d_type == DT_SUBVOL) {
1936 n->v.d_parent_subvol = cpu_to_le32(target->bi_parent_subvol);
1937 n->v.d_child_subvol = cpu_to_le32(target->bi_subvol);
1938 } else {
1939 n->v.d_inum = cpu_to_le64(target->bi_inum);
1940 }
1941
1942 ret = bch2_trans_update(trans, iter, &n->k_i, 0);
1943 if (ret)
1944 goto err;
1945
1946 d = dirent_i_to_s_c(n);
1947 }
1948 err:
1949 fsck_err:
1950 printbuf_exit(&buf);
1951 bch_err_fn(c, ret);
1952 return ret;
1953 }
1954
1955 /* find a subvolume that's a descendent of @snapshot: */
find_snapshot_subvol(struct btree_trans * trans,u32 snapshot,u32 * subvolid)1956 static int find_snapshot_subvol(struct btree_trans *trans, u32 snapshot, u32 *subvolid)
1957 {
1958 struct btree_iter iter;
1959 struct bkey_s_c k;
1960 int ret;
1961
1962 for_each_btree_key_norestart(trans, iter, BTREE_ID_subvolumes, POS_MIN, 0, k, ret) {
1963 if (k.k->type != KEY_TYPE_subvolume)
1964 continue;
1965
1966 struct bkey_s_c_subvolume s = bkey_s_c_to_subvolume(k);
1967 if (bch2_snapshot_is_ancestor(trans->c, le32_to_cpu(s.v->snapshot), snapshot)) {
1968 bch2_trans_iter_exit(trans, &iter);
1969 *subvolid = k.k->p.offset;
1970 goto found;
1971 }
1972 }
1973 if (!ret)
1974 ret = -ENOENT;
1975 found:
1976 bch2_trans_iter_exit(trans, &iter);
1977 return ret;
1978 }
1979
1980 noinline_for_stack
check_dirent_to_subvol(struct btree_trans * trans,struct btree_iter * iter,struct bkey_s_c_dirent d)1981 static int check_dirent_to_subvol(struct btree_trans *trans, struct btree_iter *iter,
1982 struct bkey_s_c_dirent d)
1983 {
1984 struct bch_fs *c = trans->c;
1985 struct btree_iter subvol_iter = {};
1986 struct bch_inode_unpacked subvol_root;
1987 u32 parent_subvol = le32_to_cpu(d.v->d_parent_subvol);
1988 u32 target_subvol = le32_to_cpu(d.v->d_child_subvol);
1989 u32 parent_snapshot;
1990 u32 new_parent_subvol = 0;
1991 u64 parent_inum;
1992 struct printbuf buf = PRINTBUF;
1993 int ret = 0;
1994
1995 ret = subvol_lookup(trans, parent_subvol, &parent_snapshot, &parent_inum);
1996 if (ret && !bch2_err_matches(ret, ENOENT))
1997 return ret;
1998
1999 if (ret ||
2000 (!ret && !bch2_snapshot_is_ancestor(c, parent_snapshot, d.k->p.snapshot))) {
2001 int ret2 = find_snapshot_subvol(trans, d.k->p.snapshot, &new_parent_subvol);
2002 if (ret2 && !bch2_err_matches(ret, ENOENT))
2003 return ret2;
2004 }
2005
2006 if (ret &&
2007 !new_parent_subvol &&
2008 (c->sb.btrees_lost_data & BIT_ULL(BTREE_ID_subvolumes))) {
2009 /*
2010 * Couldn't find a subvol for dirent's snapshot - but we lost
2011 * subvols, so we need to reconstruct:
2012 */
2013 ret = reconstruct_subvol(trans, d.k->p.snapshot, parent_subvol, 0);
2014 if (ret)
2015 return ret;
2016
2017 parent_snapshot = d.k->p.snapshot;
2018 }
2019
2020 if (fsck_err_on(ret,
2021 trans, dirent_to_missing_parent_subvol,
2022 "dirent parent_subvol points to missing subvolume\n%s",
2023 (bch2_bkey_val_to_text(&buf, c, d.s_c), buf.buf)) ||
2024 fsck_err_on(!ret && !bch2_snapshot_is_ancestor(c, parent_snapshot, d.k->p.snapshot),
2025 trans, dirent_not_visible_in_parent_subvol,
2026 "dirent not visible in parent_subvol (not an ancestor of subvol snap %u)\n%s",
2027 parent_snapshot,
2028 (bch2_bkey_val_to_text(&buf, c, d.s_c), buf.buf))) {
2029 if (!new_parent_subvol) {
2030 bch_err(c, "could not find a subvol for snapshot %u", d.k->p.snapshot);
2031 return -BCH_ERR_fsck_repair_unimplemented;
2032 }
2033
2034 struct bkey_i_dirent *new_dirent = bch2_bkey_make_mut_typed(trans, iter, &d.s_c, 0, dirent);
2035 ret = PTR_ERR_OR_ZERO(new_dirent);
2036 if (ret)
2037 goto err;
2038
2039 new_dirent->v.d_parent_subvol = cpu_to_le32(new_parent_subvol);
2040 }
2041
2042 struct bkey_s_c_subvolume s =
2043 bch2_bkey_get_iter_typed(trans, &subvol_iter,
2044 BTREE_ID_subvolumes, POS(0, target_subvol),
2045 0, subvolume);
2046 ret = bkey_err(s.s_c);
2047 if (ret && !bch2_err_matches(ret, ENOENT))
2048 return ret;
2049
2050 if (ret) {
2051 if (fsck_err(trans, dirent_to_missing_subvol,
2052 "dirent points to missing subvolume\n%s",
2053 (bch2_bkey_val_to_text(&buf, c, d.s_c), buf.buf)))
2054 return __remove_dirent(trans, d.k->p);
2055 ret = 0;
2056 goto out;
2057 }
2058
2059 if (fsck_err_on(le32_to_cpu(s.v->fs_path_parent) != parent_subvol,
2060 trans, subvol_fs_path_parent_wrong,
2061 "subvol with wrong fs_path_parent, should be be %u\n%s",
2062 parent_subvol,
2063 (bch2_bkey_val_to_text(&buf, c, s.s_c), buf.buf))) {
2064 struct bkey_i_subvolume *n =
2065 bch2_bkey_make_mut_typed(trans, &subvol_iter, &s.s_c, 0, subvolume);
2066 ret = PTR_ERR_OR_ZERO(n);
2067 if (ret)
2068 goto err;
2069
2070 n->v.fs_path_parent = cpu_to_le32(parent_subvol);
2071 }
2072
2073 u64 target_inum = le64_to_cpu(s.v->inode);
2074 u32 target_snapshot = le32_to_cpu(s.v->snapshot);
2075
2076 ret = lookup_inode(trans, target_inum, &subvol_root, &target_snapshot);
2077 if (ret && !bch2_err_matches(ret, ENOENT))
2078 goto err;
2079
2080 if (ret) {
2081 bch_err(c, "subvol %u points to missing inode root %llu", target_subvol, target_inum);
2082 ret = -BCH_ERR_fsck_repair_unimplemented;
2083 goto err;
2084 }
2085
2086 if (fsck_err_on(!ret && parent_subvol != subvol_root.bi_parent_subvol,
2087 trans, inode_bi_parent_wrong,
2088 "subvol root %llu has wrong bi_parent_subvol: got %u, should be %u",
2089 target_inum,
2090 subvol_root.bi_parent_subvol, parent_subvol)) {
2091 subvol_root.bi_parent_subvol = parent_subvol;
2092 ret = __bch2_fsck_write_inode(trans, &subvol_root, target_snapshot);
2093 if (ret)
2094 goto err;
2095 }
2096
2097 ret = check_dirent_target(trans, iter, d, &subvol_root,
2098 target_snapshot);
2099 if (ret)
2100 goto err;
2101 out:
2102 err:
2103 fsck_err:
2104 bch2_trans_iter_exit(trans, &subvol_iter);
2105 printbuf_exit(&buf);
2106 return ret;
2107 }
2108
check_dirent(struct btree_trans * trans,struct btree_iter * iter,struct bkey_s_c k,struct bch_hash_info * hash_info,struct inode_walker * dir,struct inode_walker * target,struct snapshots_seen * s)2109 static int check_dirent(struct btree_trans *trans, struct btree_iter *iter,
2110 struct bkey_s_c k,
2111 struct bch_hash_info *hash_info,
2112 struct inode_walker *dir,
2113 struct inode_walker *target,
2114 struct snapshots_seen *s)
2115 {
2116 struct bch_fs *c = trans->c;
2117 struct inode_walker_entry *i;
2118 struct printbuf buf = PRINTBUF;
2119 int ret = 0;
2120
2121 ret = bch2_check_key_has_snapshot(trans, iter, k);
2122 if (ret) {
2123 ret = ret < 0 ? ret : 0;
2124 goto out;
2125 }
2126
2127 ret = snapshots_seen_update(c, s, iter->btree_id, k.k->p);
2128 if (ret)
2129 goto err;
2130
2131 if (k.k->type == KEY_TYPE_whiteout)
2132 goto out;
2133
2134 if (dir->last_pos.inode != k.k->p.inode && dir->have_inodes) {
2135 ret = check_subdir_count(trans, dir);
2136 if (ret)
2137 goto err;
2138 }
2139
2140 i = walk_inode(trans, dir, k);
2141 ret = PTR_ERR_OR_ZERO(i);
2142 if (ret < 0)
2143 goto err;
2144
2145 ret = check_key_has_inode(trans, iter, dir, i, k);
2146 if (ret)
2147 goto err;
2148
2149 if (!i)
2150 goto out;
2151
2152 if (dir->first_this_inode)
2153 *hash_info = bch2_hash_info_init(c, &i->inode);
2154 dir->first_this_inode = false;
2155
2156 ret = hash_check_key(trans, bch2_dirent_hash_desc, hash_info, iter, k);
2157 if (ret < 0)
2158 goto err;
2159 if (ret) {
2160 /* dirent has been deleted */
2161 ret = 0;
2162 goto out;
2163 }
2164
2165 if (k.k->type != KEY_TYPE_dirent)
2166 goto out;
2167
2168 struct bkey_s_c_dirent d = bkey_s_c_to_dirent(k);
2169
2170 if (d.v->d_type == DT_SUBVOL) {
2171 ret = check_dirent_to_subvol(trans, iter, d);
2172 if (ret)
2173 goto err;
2174 } else {
2175 ret = get_visible_inodes(trans, target, s, le64_to_cpu(d.v->d_inum));
2176 if (ret)
2177 goto err;
2178
2179 if (fsck_err_on(!target->inodes.nr,
2180 trans, dirent_to_missing_inode,
2181 "dirent points to missing inode:\n%s",
2182 (printbuf_reset(&buf),
2183 bch2_bkey_val_to_text(&buf, c, k),
2184 buf.buf))) {
2185 ret = __remove_dirent(trans, d.k->p);
2186 if (ret)
2187 goto err;
2188 }
2189
2190 darray_for_each(target->inodes, i) {
2191 ret = check_dirent_target(trans, iter, d,
2192 &i->inode, i->snapshot);
2193 if (ret)
2194 goto err;
2195 }
2196 }
2197
2198 ret = bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc);
2199 if (ret)
2200 goto err;
2201
2202 if (d.v->d_type == DT_DIR)
2203 for_each_visible_inode(c, s, dir, d.k->p.snapshot, i)
2204 i->count++;
2205 out:
2206 err:
2207 fsck_err:
2208 printbuf_exit(&buf);
2209 bch_err_fn(c, ret);
2210 return ret;
2211 }
2212
2213 /*
2214 * Walk dirents: verify that they all have a corresponding S_ISDIR inode,
2215 * validate d_type
2216 */
bch2_check_dirents(struct bch_fs * c)2217 int bch2_check_dirents(struct bch_fs *c)
2218 {
2219 struct inode_walker dir = inode_walker_init();
2220 struct inode_walker target = inode_walker_init();
2221 struct snapshots_seen s;
2222 struct bch_hash_info hash_info;
2223
2224 snapshots_seen_init(&s);
2225
2226 int ret = bch2_trans_run(c,
2227 for_each_btree_key(trans, iter, BTREE_ID_dirents,
2228 POS(BCACHEFS_ROOT_INO, 0),
2229 BTREE_ITER_prefetch|BTREE_ITER_all_snapshots, k,
2230 check_dirent(trans, &iter, k, &hash_info, &dir, &target, &s)) ?:
2231 check_subdir_count_notnested(trans, &dir));
2232
2233 snapshots_seen_exit(&s);
2234 inode_walker_exit(&dir);
2235 inode_walker_exit(&target);
2236 bch_err_fn(c, ret);
2237 return ret;
2238 }
2239
check_xattr(struct btree_trans * trans,struct btree_iter * iter,struct bkey_s_c k,struct bch_hash_info * hash_info,struct inode_walker * inode)2240 static int check_xattr(struct btree_trans *trans, struct btree_iter *iter,
2241 struct bkey_s_c k,
2242 struct bch_hash_info *hash_info,
2243 struct inode_walker *inode)
2244 {
2245 struct bch_fs *c = trans->c;
2246 struct inode_walker_entry *i;
2247 int ret;
2248
2249 ret = bch2_check_key_has_snapshot(trans, iter, k);
2250 if (ret < 0)
2251 return ret;
2252 if (ret)
2253 return 0;
2254
2255 i = walk_inode(trans, inode, k);
2256 ret = PTR_ERR_OR_ZERO(i);
2257 if (ret)
2258 return ret;
2259
2260 ret = check_key_has_inode(trans, iter, inode, i, k);
2261 if (ret)
2262 return ret;
2263
2264 if (!i)
2265 return 0;
2266
2267 if (inode->first_this_inode)
2268 *hash_info = bch2_hash_info_init(c, &i->inode);
2269 inode->first_this_inode = false;
2270
2271 ret = hash_check_key(trans, bch2_xattr_hash_desc, hash_info, iter, k);
2272 bch_err_fn(c, ret);
2273 return ret;
2274 }
2275
2276 /*
2277 * Walk xattrs: verify that they all have a corresponding inode
2278 */
bch2_check_xattrs(struct bch_fs * c)2279 int bch2_check_xattrs(struct bch_fs *c)
2280 {
2281 struct inode_walker inode = inode_walker_init();
2282 struct bch_hash_info hash_info;
2283 int ret = 0;
2284
2285 ret = bch2_trans_run(c,
2286 for_each_btree_key_commit(trans, iter, BTREE_ID_xattrs,
2287 POS(BCACHEFS_ROOT_INO, 0),
2288 BTREE_ITER_prefetch|BTREE_ITER_all_snapshots,
2289 k,
2290 NULL, NULL,
2291 BCH_TRANS_COMMIT_no_enospc,
2292 check_xattr(trans, &iter, k, &hash_info, &inode)));
2293
2294 inode_walker_exit(&inode);
2295 bch_err_fn(c, ret);
2296 return ret;
2297 }
2298
check_root_trans(struct btree_trans * trans)2299 static int check_root_trans(struct btree_trans *trans)
2300 {
2301 struct bch_fs *c = trans->c;
2302 struct bch_inode_unpacked root_inode;
2303 u32 snapshot;
2304 u64 inum;
2305 int ret;
2306
2307 ret = subvol_lookup(trans, BCACHEFS_ROOT_SUBVOL, &snapshot, &inum);
2308 if (ret && !bch2_err_matches(ret, ENOENT))
2309 return ret;
2310
2311 if (mustfix_fsck_err_on(ret, trans, root_subvol_missing,
2312 "root subvol missing")) {
2313 struct bkey_i_subvolume *root_subvol =
2314 bch2_trans_kmalloc(trans, sizeof(*root_subvol));
2315 ret = PTR_ERR_OR_ZERO(root_subvol);
2316 if (ret)
2317 goto err;
2318
2319 snapshot = U32_MAX;
2320 inum = BCACHEFS_ROOT_INO;
2321
2322 bkey_subvolume_init(&root_subvol->k_i);
2323 root_subvol->k.p.offset = BCACHEFS_ROOT_SUBVOL;
2324 root_subvol->v.flags = 0;
2325 root_subvol->v.snapshot = cpu_to_le32(snapshot);
2326 root_subvol->v.inode = cpu_to_le64(inum);
2327 ret = bch2_btree_insert_trans(trans, BTREE_ID_subvolumes, &root_subvol->k_i, 0);
2328 bch_err_msg(c, ret, "writing root subvol");
2329 if (ret)
2330 goto err;
2331 }
2332
2333 ret = lookup_inode(trans, BCACHEFS_ROOT_INO, &root_inode, &snapshot);
2334 if (ret && !bch2_err_matches(ret, ENOENT))
2335 return ret;
2336
2337 if (mustfix_fsck_err_on(ret,
2338 trans, root_dir_missing,
2339 "root directory missing") ||
2340 mustfix_fsck_err_on(!S_ISDIR(root_inode.bi_mode),
2341 trans, root_inode_not_dir,
2342 "root inode not a directory")) {
2343 bch2_inode_init(c, &root_inode, 0, 0, S_IFDIR|0755,
2344 0, NULL);
2345 root_inode.bi_inum = inum;
2346
2347 ret = __bch2_fsck_write_inode(trans, &root_inode, snapshot);
2348 bch_err_msg(c, ret, "writing root inode");
2349 }
2350 err:
2351 fsck_err:
2352 return ret;
2353 }
2354
2355 /* Get root directory, create if it doesn't exist: */
bch2_check_root(struct bch_fs * c)2356 int bch2_check_root(struct bch_fs *c)
2357 {
2358 int ret = bch2_trans_do(c, NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
2359 check_root_trans(trans));
2360 bch_err_fn(c, ret);
2361 return ret;
2362 }
2363
2364 typedef DARRAY(u32) darray_u32;
2365
darray_u32_has(darray_u32 * d,u32 v)2366 static bool darray_u32_has(darray_u32 *d, u32 v)
2367 {
2368 darray_for_each(*d, i)
2369 if (*i == v)
2370 return true;
2371 return false;
2372 }
2373
check_subvol_path(struct btree_trans * trans,struct btree_iter * iter,struct bkey_s_c k)2374 static int check_subvol_path(struct btree_trans *trans, struct btree_iter *iter, struct bkey_s_c k)
2375 {
2376 struct bch_fs *c = trans->c;
2377 struct btree_iter parent_iter = {};
2378 darray_u32 subvol_path = {};
2379 struct printbuf buf = PRINTBUF;
2380 int ret = 0;
2381
2382 if (k.k->type != KEY_TYPE_subvolume)
2383 return 0;
2384
2385 while (k.k->p.offset != BCACHEFS_ROOT_SUBVOL) {
2386 ret = darray_push(&subvol_path, k.k->p.offset);
2387 if (ret)
2388 goto err;
2389
2390 struct bkey_s_c_subvolume s = bkey_s_c_to_subvolume(k);
2391
2392 struct bch_inode_unpacked subvol_root;
2393 ret = bch2_inode_find_by_inum_trans(trans,
2394 (subvol_inum) { s.k->p.offset, le64_to_cpu(s.v->inode) },
2395 &subvol_root);
2396 if (ret)
2397 break;
2398
2399 /*
2400 * We've checked that inode backpointers point to valid dirents;
2401 * here, it's sufficient to check that the subvolume root has a
2402 * dirent:
2403 */
2404 if (fsck_err_on(!subvol_root.bi_dir,
2405 trans, subvol_unreachable,
2406 "unreachable subvolume %s",
2407 (bch2_bkey_val_to_text(&buf, c, s.s_c),
2408 prt_newline(&buf),
2409 bch2_inode_unpacked_to_text(&buf, &subvol_root),
2410 buf.buf))) {
2411 ret = reattach_subvol(trans, s);
2412 break;
2413 }
2414
2415 u32 parent = le32_to_cpu(s.v->fs_path_parent);
2416
2417 if (darray_u32_has(&subvol_path, parent)) {
2418 if (fsck_err(c, subvol_loop, "subvolume loop"))
2419 ret = reattach_subvol(trans, s);
2420 break;
2421 }
2422
2423 bch2_trans_iter_exit(trans, &parent_iter);
2424 bch2_trans_iter_init(trans, &parent_iter,
2425 BTREE_ID_subvolumes, POS(0, parent), 0);
2426 k = bch2_btree_iter_peek_slot(&parent_iter);
2427 ret = bkey_err(k);
2428 if (ret)
2429 goto err;
2430
2431 if (fsck_err_on(k.k->type != KEY_TYPE_subvolume,
2432 trans, subvol_unreachable,
2433 "unreachable subvolume %s",
2434 (bch2_bkey_val_to_text(&buf, c, s.s_c),
2435 buf.buf))) {
2436 ret = reattach_subvol(trans, s);
2437 break;
2438 }
2439 }
2440 fsck_err:
2441 err:
2442 printbuf_exit(&buf);
2443 darray_exit(&subvol_path);
2444 bch2_trans_iter_exit(trans, &parent_iter);
2445 return ret;
2446 }
2447
bch2_check_subvolume_structure(struct bch_fs * c)2448 int bch2_check_subvolume_structure(struct bch_fs *c)
2449 {
2450 int ret = bch2_trans_run(c,
2451 for_each_btree_key_commit(trans, iter,
2452 BTREE_ID_subvolumes, POS_MIN, BTREE_ITER_prefetch, k,
2453 NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
2454 check_subvol_path(trans, &iter, k)));
2455 bch_err_fn(c, ret);
2456 return ret;
2457 }
2458
2459 struct pathbuf_entry {
2460 u64 inum;
2461 u32 snapshot;
2462 };
2463
2464 typedef DARRAY(struct pathbuf_entry) pathbuf;
2465
path_is_dup(pathbuf * p,u64 inum,u32 snapshot)2466 static bool path_is_dup(pathbuf *p, u64 inum, u32 snapshot)
2467 {
2468 darray_for_each(*p, i)
2469 if (i->inum == inum &&
2470 i->snapshot == snapshot)
2471 return true;
2472 return false;
2473 }
2474
2475 /*
2476 * Check that a given inode is reachable from its subvolume root - we already
2477 * verified subvolume connectivity:
2478 *
2479 * XXX: we should also be verifying that inodes are in the right subvolumes
2480 */
check_path(struct btree_trans * trans,pathbuf * p,struct bkey_s_c inode_k)2481 static int check_path(struct btree_trans *trans, pathbuf *p, struct bkey_s_c inode_k)
2482 {
2483 struct bch_fs *c = trans->c;
2484 struct btree_iter inode_iter = {};
2485 struct bch_inode_unpacked inode;
2486 struct printbuf buf = PRINTBUF;
2487 u32 snapshot = inode_k.k->p.snapshot;
2488 int ret = 0;
2489
2490 p->nr = 0;
2491
2492 BUG_ON(bch2_inode_unpack(inode_k, &inode));
2493
2494 while (!inode.bi_subvol) {
2495 struct btree_iter dirent_iter;
2496 struct bkey_s_c_dirent d;
2497 u32 parent_snapshot = snapshot;
2498
2499 d = inode_get_dirent(trans, &dirent_iter, &inode, &parent_snapshot);
2500 ret = bkey_err(d.s_c);
2501 if (ret && !bch2_err_matches(ret, ENOENT))
2502 break;
2503
2504 if (!ret && (ret = dirent_points_to_inode(c, d, &inode)))
2505 bch2_trans_iter_exit(trans, &dirent_iter);
2506
2507 if (bch2_err_matches(ret, ENOENT)) {
2508 ret = 0;
2509 if (fsck_err(trans, inode_unreachable,
2510 "unreachable inode\n%s",
2511 (printbuf_reset(&buf),
2512 bch2_bkey_val_to_text(&buf, c, inode_k),
2513 buf.buf)))
2514 ret = reattach_inode(trans, &inode, snapshot);
2515 goto out;
2516 }
2517
2518 bch2_trans_iter_exit(trans, &dirent_iter);
2519
2520 if (!S_ISDIR(inode.bi_mode))
2521 break;
2522
2523 ret = darray_push(p, ((struct pathbuf_entry) {
2524 .inum = inode.bi_inum,
2525 .snapshot = snapshot,
2526 }));
2527 if (ret)
2528 return ret;
2529
2530 snapshot = parent_snapshot;
2531
2532 bch2_trans_iter_exit(trans, &inode_iter);
2533 inode_k = bch2_bkey_get_iter(trans, &inode_iter, BTREE_ID_inodes,
2534 SPOS(0, inode.bi_dir, snapshot), 0);
2535 ret = bkey_err(inode_k) ?:
2536 !bkey_is_inode(inode_k.k) ? -BCH_ERR_ENOENT_inode
2537 : bch2_inode_unpack(inode_k, &inode);
2538 if (ret) {
2539 /* Should have been caught in dirents pass */
2540 bch_err_msg(c, ret, "error looking up parent directory");
2541 break;
2542 }
2543
2544 snapshot = inode_k.k->p.snapshot;
2545
2546 if (path_is_dup(p, inode.bi_inum, snapshot)) {
2547 /* XXX print path */
2548 bch_err(c, "directory structure loop");
2549
2550 darray_for_each(*p, i)
2551 pr_err("%llu:%u", i->inum, i->snapshot);
2552 pr_err("%llu:%u", inode.bi_inum, snapshot);
2553
2554 if (fsck_err(trans, dir_loop, "directory structure loop")) {
2555 ret = remove_backpointer(trans, &inode);
2556 bch_err_msg(c, ret, "removing dirent");
2557 if (ret)
2558 break;
2559
2560 ret = reattach_inode(trans, &inode, snapshot);
2561 bch_err_msg(c, ret, "reattaching inode %llu", inode.bi_inum);
2562 }
2563 break;
2564 }
2565 }
2566 out:
2567 fsck_err:
2568 bch2_trans_iter_exit(trans, &inode_iter);
2569 printbuf_exit(&buf);
2570 bch_err_fn(c, ret);
2571 return ret;
2572 }
2573
2574 /*
2575 * Check for unreachable inodes, as well as loops in the directory structure:
2576 * After bch2_check_dirents(), if an inode backpointer doesn't exist that means it's
2577 * unreachable:
2578 */
bch2_check_directory_structure(struct bch_fs * c)2579 int bch2_check_directory_structure(struct bch_fs *c)
2580 {
2581 pathbuf path = { 0, };
2582 int ret;
2583
2584 ret = bch2_trans_run(c,
2585 for_each_btree_key_commit(trans, iter, BTREE_ID_inodes, POS_MIN,
2586 BTREE_ITER_intent|
2587 BTREE_ITER_prefetch|
2588 BTREE_ITER_all_snapshots, k,
2589 NULL, NULL, BCH_TRANS_COMMIT_no_enospc, ({
2590 if (!bkey_is_inode(k.k))
2591 continue;
2592
2593 if (bch2_inode_flags(k) & BCH_INODE_unlinked)
2594 continue;
2595
2596 check_path(trans, &path, k);
2597 })));
2598 darray_exit(&path);
2599
2600 bch_err_fn(c, ret);
2601 return ret;
2602 }
2603
2604 struct nlink_table {
2605 size_t nr;
2606 size_t size;
2607
2608 struct nlink {
2609 u64 inum;
2610 u32 snapshot;
2611 u32 count;
2612 } *d;
2613 };
2614
add_nlink(struct bch_fs * c,struct nlink_table * t,u64 inum,u32 snapshot)2615 static int add_nlink(struct bch_fs *c, struct nlink_table *t,
2616 u64 inum, u32 snapshot)
2617 {
2618 if (t->nr == t->size) {
2619 size_t new_size = max_t(size_t, 128UL, t->size * 2);
2620 void *d = kvmalloc_array(new_size, sizeof(t->d[0]), GFP_KERNEL);
2621
2622 if (!d) {
2623 bch_err(c, "fsck: error allocating memory for nlink_table, size %zu",
2624 new_size);
2625 return -BCH_ERR_ENOMEM_fsck_add_nlink;
2626 }
2627
2628 if (t->d)
2629 memcpy(d, t->d, t->size * sizeof(t->d[0]));
2630 kvfree(t->d);
2631
2632 t->d = d;
2633 t->size = new_size;
2634 }
2635
2636
2637 t->d[t->nr++] = (struct nlink) {
2638 .inum = inum,
2639 .snapshot = snapshot,
2640 };
2641
2642 return 0;
2643 }
2644
nlink_cmp(const void * _l,const void * _r)2645 static int nlink_cmp(const void *_l, const void *_r)
2646 {
2647 const struct nlink *l = _l;
2648 const struct nlink *r = _r;
2649
2650 return cmp_int(l->inum, r->inum);
2651 }
2652
inc_link(struct bch_fs * c,struct snapshots_seen * s,struct nlink_table * links,u64 range_start,u64 range_end,u64 inum,u32 snapshot)2653 static void inc_link(struct bch_fs *c, struct snapshots_seen *s,
2654 struct nlink_table *links,
2655 u64 range_start, u64 range_end, u64 inum, u32 snapshot)
2656 {
2657 struct nlink *link, key = {
2658 .inum = inum, .snapshot = U32_MAX,
2659 };
2660
2661 if (inum < range_start || inum >= range_end)
2662 return;
2663
2664 link = __inline_bsearch(&key, links->d, links->nr,
2665 sizeof(links->d[0]), nlink_cmp);
2666 if (!link)
2667 return;
2668
2669 while (link > links->d && link[0].inum == link[-1].inum)
2670 --link;
2671
2672 for (; link < links->d + links->nr && link->inum == inum; link++)
2673 if (ref_visible(c, s, snapshot, link->snapshot)) {
2674 link->count++;
2675 if (link->snapshot >= snapshot)
2676 break;
2677 }
2678 }
2679
2680 noinline_for_stack
check_nlinks_find_hardlinks(struct bch_fs * c,struct nlink_table * t,u64 start,u64 * end)2681 static int check_nlinks_find_hardlinks(struct bch_fs *c,
2682 struct nlink_table *t,
2683 u64 start, u64 *end)
2684 {
2685 int ret = bch2_trans_run(c,
2686 for_each_btree_key(trans, iter, BTREE_ID_inodes,
2687 POS(0, start),
2688 BTREE_ITER_intent|
2689 BTREE_ITER_prefetch|
2690 BTREE_ITER_all_snapshots, k, ({
2691 if (!bkey_is_inode(k.k))
2692 continue;
2693
2694 /* Should never fail, checked by bch2_inode_invalid: */
2695 struct bch_inode_unpacked u;
2696 BUG_ON(bch2_inode_unpack(k, &u));
2697
2698 /*
2699 * Backpointer and directory structure checks are sufficient for
2700 * directories, since they can't have hardlinks:
2701 */
2702 if (S_ISDIR(u.bi_mode))
2703 continue;
2704
2705 if (!u.bi_nlink)
2706 continue;
2707
2708 ret = add_nlink(c, t, k.k->p.offset, k.k->p.snapshot);
2709 if (ret) {
2710 *end = k.k->p.offset;
2711 ret = 0;
2712 break;
2713 }
2714 0;
2715 })));
2716
2717 bch_err_fn(c, ret);
2718 return ret;
2719 }
2720
2721 noinline_for_stack
check_nlinks_walk_dirents(struct bch_fs * c,struct nlink_table * links,u64 range_start,u64 range_end)2722 static int check_nlinks_walk_dirents(struct bch_fs *c, struct nlink_table *links,
2723 u64 range_start, u64 range_end)
2724 {
2725 struct snapshots_seen s;
2726
2727 snapshots_seen_init(&s);
2728
2729 int ret = bch2_trans_run(c,
2730 for_each_btree_key(trans, iter, BTREE_ID_dirents, POS_MIN,
2731 BTREE_ITER_intent|
2732 BTREE_ITER_prefetch|
2733 BTREE_ITER_all_snapshots, k, ({
2734 ret = snapshots_seen_update(c, &s, iter.btree_id, k.k->p);
2735 if (ret)
2736 break;
2737
2738 if (k.k->type == KEY_TYPE_dirent) {
2739 struct bkey_s_c_dirent d = bkey_s_c_to_dirent(k);
2740
2741 if (d.v->d_type != DT_DIR &&
2742 d.v->d_type != DT_SUBVOL)
2743 inc_link(c, &s, links, range_start, range_end,
2744 le64_to_cpu(d.v->d_inum), d.k->p.snapshot);
2745 }
2746 0;
2747 })));
2748
2749 snapshots_seen_exit(&s);
2750
2751 bch_err_fn(c, ret);
2752 return ret;
2753 }
2754
check_nlinks_update_inode(struct btree_trans * trans,struct btree_iter * iter,struct bkey_s_c k,struct nlink_table * links,size_t * idx,u64 range_end)2755 static int check_nlinks_update_inode(struct btree_trans *trans, struct btree_iter *iter,
2756 struct bkey_s_c k,
2757 struct nlink_table *links,
2758 size_t *idx, u64 range_end)
2759 {
2760 struct bch_inode_unpacked u;
2761 struct nlink *link = &links->d[*idx];
2762 int ret = 0;
2763
2764 if (k.k->p.offset >= range_end)
2765 return 1;
2766
2767 if (!bkey_is_inode(k.k))
2768 return 0;
2769
2770 BUG_ON(bch2_inode_unpack(k, &u));
2771
2772 if (S_ISDIR(u.bi_mode))
2773 return 0;
2774
2775 if (!u.bi_nlink)
2776 return 0;
2777
2778 while ((cmp_int(link->inum, k.k->p.offset) ?:
2779 cmp_int(link->snapshot, k.k->p.snapshot)) < 0) {
2780 BUG_ON(*idx == links->nr);
2781 link = &links->d[++*idx];
2782 }
2783
2784 if (fsck_err_on(bch2_inode_nlink_get(&u) != link->count,
2785 trans, inode_wrong_nlink,
2786 "inode %llu type %s has wrong i_nlink (%u, should be %u)",
2787 u.bi_inum, bch2_d_types[mode_to_type(u.bi_mode)],
2788 bch2_inode_nlink_get(&u), link->count)) {
2789 bch2_inode_nlink_set(&u, link->count);
2790 ret = __bch2_fsck_write_inode(trans, &u, k.k->p.snapshot);
2791 }
2792 fsck_err:
2793 return ret;
2794 }
2795
2796 noinline_for_stack
check_nlinks_update_hardlinks(struct bch_fs * c,struct nlink_table * links,u64 range_start,u64 range_end)2797 static int check_nlinks_update_hardlinks(struct bch_fs *c,
2798 struct nlink_table *links,
2799 u64 range_start, u64 range_end)
2800 {
2801 size_t idx = 0;
2802
2803 int ret = bch2_trans_run(c,
2804 for_each_btree_key_commit(trans, iter, BTREE_ID_inodes,
2805 POS(0, range_start),
2806 BTREE_ITER_intent|BTREE_ITER_prefetch|BTREE_ITER_all_snapshots, k,
2807 NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
2808 check_nlinks_update_inode(trans, &iter, k, links, &idx, range_end)));
2809 if (ret < 0) {
2810 bch_err(c, "error in fsck walking inodes: %s", bch2_err_str(ret));
2811 return ret;
2812 }
2813
2814 return 0;
2815 }
2816
bch2_check_nlinks(struct bch_fs * c)2817 int bch2_check_nlinks(struct bch_fs *c)
2818 {
2819 struct nlink_table links = { 0 };
2820 u64 this_iter_range_start, next_iter_range_start = 0;
2821 int ret = 0;
2822
2823 do {
2824 this_iter_range_start = next_iter_range_start;
2825 next_iter_range_start = U64_MAX;
2826
2827 ret = check_nlinks_find_hardlinks(c, &links,
2828 this_iter_range_start,
2829 &next_iter_range_start);
2830
2831 ret = check_nlinks_walk_dirents(c, &links,
2832 this_iter_range_start,
2833 next_iter_range_start);
2834 if (ret)
2835 break;
2836
2837 ret = check_nlinks_update_hardlinks(c, &links,
2838 this_iter_range_start,
2839 next_iter_range_start);
2840 if (ret)
2841 break;
2842
2843 links.nr = 0;
2844 } while (next_iter_range_start != U64_MAX);
2845
2846 kvfree(links.d);
2847 bch_err_fn(c, ret);
2848 return ret;
2849 }
2850
fix_reflink_p_key(struct btree_trans * trans,struct btree_iter * iter,struct bkey_s_c k)2851 static int fix_reflink_p_key(struct btree_trans *trans, struct btree_iter *iter,
2852 struct bkey_s_c k)
2853 {
2854 struct bkey_s_c_reflink_p p;
2855 struct bkey_i_reflink_p *u;
2856
2857 if (k.k->type != KEY_TYPE_reflink_p)
2858 return 0;
2859
2860 p = bkey_s_c_to_reflink_p(k);
2861
2862 if (!p.v->front_pad && !p.v->back_pad)
2863 return 0;
2864
2865 u = bch2_trans_kmalloc(trans, sizeof(*u));
2866 int ret = PTR_ERR_OR_ZERO(u);
2867 if (ret)
2868 return ret;
2869
2870 bkey_reassemble(&u->k_i, k);
2871 u->v.front_pad = 0;
2872 u->v.back_pad = 0;
2873
2874 return bch2_trans_update(trans, iter, &u->k_i, BTREE_TRIGGER_norun);
2875 }
2876
bch2_fix_reflink_p(struct bch_fs * c)2877 int bch2_fix_reflink_p(struct bch_fs *c)
2878 {
2879 if (c->sb.version >= bcachefs_metadata_version_reflink_p_fix)
2880 return 0;
2881
2882 int ret = bch2_trans_run(c,
2883 for_each_btree_key_commit(trans, iter,
2884 BTREE_ID_extents, POS_MIN,
2885 BTREE_ITER_intent|BTREE_ITER_prefetch|
2886 BTREE_ITER_all_snapshots, k,
2887 NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
2888 fix_reflink_p_key(trans, &iter, k)));
2889 bch_err_fn(c, ret);
2890 return ret;
2891 }
2892