1 // SPDX-License-Identifier: GPL-2.0
2
3 #include "bcachefs.h"
4 #include "acl.h"
5 #include "btree_update.h"
6 #include "dirent.h"
7 #include "fs-common.h"
8 #include "inode.h"
9 #include "subvolume.h"
10 #include "xattr.h"
11
12 #include <linux/posix_acl.h>
13
is_subdir_for_nlink(struct bch_inode_unpacked * inode)14 static inline int is_subdir_for_nlink(struct bch_inode_unpacked *inode)
15 {
16 return S_ISDIR(inode->bi_mode) && !inode->bi_subvol;
17 }
18
bch2_create_trans(struct btree_trans * trans,subvol_inum dir,struct bch_inode_unpacked * dir_u,struct bch_inode_unpacked * new_inode,const struct qstr * name,uid_t uid,gid_t gid,umode_t mode,dev_t rdev,struct posix_acl * default_acl,struct posix_acl * acl,subvol_inum snapshot_src,unsigned flags)19 int bch2_create_trans(struct btree_trans *trans,
20 subvol_inum dir,
21 struct bch_inode_unpacked *dir_u,
22 struct bch_inode_unpacked *new_inode,
23 const struct qstr *name,
24 uid_t uid, gid_t gid, umode_t mode, dev_t rdev,
25 struct posix_acl *default_acl,
26 struct posix_acl *acl,
27 subvol_inum snapshot_src,
28 unsigned flags)
29 {
30 struct bch_fs *c = trans->c;
31 struct btree_iter dir_iter = { NULL };
32 struct btree_iter inode_iter = { NULL };
33 subvol_inum new_inum = dir;
34 u64 now = bch2_current_time(c);
35 u64 cpu = raw_smp_processor_id();
36 u64 dir_target;
37 u32 snapshot;
38 unsigned dir_type = mode_to_type(mode);
39 int ret;
40
41 ret = bch2_subvolume_get_snapshot(trans, dir.subvol, &snapshot);
42 if (ret)
43 goto err;
44
45 ret = bch2_inode_peek(trans, &dir_iter, dir_u, dir,
46 BTREE_ITER_intent|BTREE_ITER_with_updates);
47 if (ret)
48 goto err;
49
50 if (!(flags & BCH_CREATE_SNAPSHOT)) {
51 /* Normal create path - allocate a new inode: */
52 bch2_inode_init_late(new_inode, now, uid, gid, mode, rdev, dir_u);
53
54 if (flags & BCH_CREATE_TMPFILE)
55 new_inode->bi_flags |= BCH_INODE_unlinked;
56
57 ret = bch2_inode_create(trans, &inode_iter, new_inode, snapshot, cpu);
58 if (ret)
59 goto err;
60
61 snapshot_src = (subvol_inum) { 0 };
62 } else {
63 /*
64 * Creating a snapshot - we're not allocating a new inode, but
65 * we do have to lookup the root inode of the subvolume we're
66 * snapshotting and update it (in the new snapshot):
67 */
68
69 if (!snapshot_src.inum) {
70 /* Inode wasn't specified, just snapshot: */
71 struct bch_subvolume s;
72
73 ret = bch2_subvolume_get(trans, snapshot_src.subvol, true,
74 BTREE_ITER_cached, &s);
75 if (ret)
76 goto err;
77
78 snapshot_src.inum = le64_to_cpu(s.inode);
79 }
80
81 ret = bch2_inode_peek(trans, &inode_iter, new_inode, snapshot_src,
82 BTREE_ITER_intent);
83 if (ret)
84 goto err;
85
86 if (new_inode->bi_subvol != snapshot_src.subvol) {
87 /* Not a subvolume root: */
88 ret = -EINVAL;
89 goto err;
90 }
91
92 /*
93 * If we're not root, we have to own the subvolume being
94 * snapshotted:
95 */
96 if (uid && new_inode->bi_uid != uid) {
97 ret = -EPERM;
98 goto err;
99 }
100
101 flags |= BCH_CREATE_SUBVOL;
102 }
103
104 new_inum.inum = new_inode->bi_inum;
105 dir_target = new_inode->bi_inum;
106
107 if (flags & BCH_CREATE_SUBVOL) {
108 u32 new_subvol, dir_snapshot;
109
110 ret = bch2_subvolume_create(trans, new_inode->bi_inum,
111 dir.subvol,
112 snapshot_src.subvol,
113 &new_subvol, &snapshot,
114 (flags & BCH_CREATE_SNAPSHOT_RO) != 0);
115 if (ret)
116 goto err;
117
118 new_inode->bi_parent_subvol = dir.subvol;
119 new_inode->bi_subvol = new_subvol;
120 new_inum.subvol = new_subvol;
121 dir_target = new_subvol;
122 dir_type = DT_SUBVOL;
123
124 ret = bch2_subvolume_get_snapshot(trans, dir.subvol, &dir_snapshot);
125 if (ret)
126 goto err;
127
128 bch2_btree_iter_set_snapshot(&dir_iter, dir_snapshot);
129 ret = bch2_btree_iter_traverse(&dir_iter);
130 if (ret)
131 goto err;
132 }
133
134 if (!(flags & BCH_CREATE_SNAPSHOT)) {
135 if (default_acl) {
136 ret = bch2_set_acl_trans(trans, new_inum, new_inode,
137 default_acl, ACL_TYPE_DEFAULT);
138 if (ret)
139 goto err;
140 }
141
142 if (acl) {
143 ret = bch2_set_acl_trans(trans, new_inum, new_inode,
144 acl, ACL_TYPE_ACCESS);
145 if (ret)
146 goto err;
147 }
148 }
149
150 if (!(flags & BCH_CREATE_TMPFILE)) {
151 struct bch_hash_info dir_hash = bch2_hash_info_init(c, dir_u);
152 u64 dir_offset;
153
154 if (is_subdir_for_nlink(new_inode))
155 dir_u->bi_nlink++;
156 dir_u->bi_mtime = dir_u->bi_ctime = now;
157
158 ret = bch2_inode_write(trans, &dir_iter, dir_u);
159 if (ret)
160 goto err;
161
162 ret = bch2_dirent_create(trans, dir, &dir_hash,
163 dir_type,
164 name,
165 dir_target,
166 &dir_offset,
167 STR_HASH_must_create|BTREE_ITER_with_updates);
168 if (ret)
169 goto err;
170
171 new_inode->bi_dir = dir_u->bi_inum;
172 new_inode->bi_dir_offset = dir_offset;
173 }
174
175 inode_iter.flags &= ~BTREE_ITER_all_snapshots;
176 bch2_btree_iter_set_snapshot(&inode_iter, snapshot);
177
178 ret = bch2_btree_iter_traverse(&inode_iter) ?:
179 bch2_inode_write(trans, &inode_iter, new_inode);
180 err:
181 bch2_trans_iter_exit(trans, &inode_iter);
182 bch2_trans_iter_exit(trans, &dir_iter);
183 return ret;
184 }
185
bch2_link_trans(struct btree_trans * trans,subvol_inum dir,struct bch_inode_unpacked * dir_u,subvol_inum inum,struct bch_inode_unpacked * inode_u,const struct qstr * name)186 int bch2_link_trans(struct btree_trans *trans,
187 subvol_inum dir, struct bch_inode_unpacked *dir_u,
188 subvol_inum inum, struct bch_inode_unpacked *inode_u,
189 const struct qstr *name)
190 {
191 struct bch_fs *c = trans->c;
192 struct btree_iter dir_iter = { NULL };
193 struct btree_iter inode_iter = { NULL };
194 struct bch_hash_info dir_hash;
195 u64 now = bch2_current_time(c);
196 u64 dir_offset = 0;
197 int ret;
198
199 if (dir.subvol != inum.subvol)
200 return -EXDEV;
201
202 ret = bch2_inode_peek(trans, &inode_iter, inode_u, inum, BTREE_ITER_intent);
203 if (ret)
204 return ret;
205
206 inode_u->bi_ctime = now;
207 ret = bch2_inode_nlink_inc(inode_u);
208 if (ret)
209 goto err;
210
211 ret = bch2_inode_peek(trans, &dir_iter, dir_u, dir, BTREE_ITER_intent);
212 if (ret)
213 goto err;
214
215 if (bch2_reinherit_attrs(inode_u, dir_u)) {
216 ret = -EXDEV;
217 goto err;
218 }
219
220 dir_u->bi_mtime = dir_u->bi_ctime = now;
221
222 dir_hash = bch2_hash_info_init(c, dir_u);
223
224 ret = bch2_dirent_create(trans, dir, &dir_hash,
225 mode_to_type(inode_u->bi_mode),
226 name, inum.inum, &dir_offset,
227 STR_HASH_must_create);
228 if (ret)
229 goto err;
230
231 inode_u->bi_dir = dir.inum;
232 inode_u->bi_dir_offset = dir_offset;
233
234 ret = bch2_inode_write(trans, &dir_iter, dir_u) ?:
235 bch2_inode_write(trans, &inode_iter, inode_u);
236 err:
237 bch2_trans_iter_exit(trans, &dir_iter);
238 bch2_trans_iter_exit(trans, &inode_iter);
239 return ret;
240 }
241
bch2_unlink_trans(struct btree_trans * trans,subvol_inum dir,struct bch_inode_unpacked * dir_u,struct bch_inode_unpacked * inode_u,const struct qstr * name,bool deleting_subvol)242 int bch2_unlink_trans(struct btree_trans *trans,
243 subvol_inum dir,
244 struct bch_inode_unpacked *dir_u,
245 struct bch_inode_unpacked *inode_u,
246 const struct qstr *name,
247 bool deleting_subvol)
248 {
249 struct bch_fs *c = trans->c;
250 struct btree_iter dir_iter = { NULL };
251 struct btree_iter dirent_iter = { NULL };
252 struct btree_iter inode_iter = { NULL };
253 struct bch_hash_info dir_hash;
254 subvol_inum inum;
255 u64 now = bch2_current_time(c);
256 struct bkey_s_c k;
257 int ret;
258
259 ret = bch2_inode_peek(trans, &dir_iter, dir_u, dir, BTREE_ITER_intent);
260 if (ret)
261 goto err;
262
263 dir_hash = bch2_hash_info_init(c, dir_u);
264
265 ret = bch2_dirent_lookup_trans(trans, &dirent_iter, dir, &dir_hash,
266 name, &inum, BTREE_ITER_intent);
267 if (ret)
268 goto err;
269
270 ret = bch2_inode_peek(trans, &inode_iter, inode_u, inum,
271 BTREE_ITER_intent);
272 if (ret)
273 goto err;
274
275 if (!deleting_subvol && S_ISDIR(inode_u->bi_mode)) {
276 ret = bch2_empty_dir_trans(trans, inum);
277 if (ret)
278 goto err;
279 }
280
281 if (deleting_subvol && !inode_u->bi_subvol) {
282 ret = -BCH_ERR_ENOENT_not_subvol;
283 goto err;
284 }
285
286 if (inode_u->bi_subvol) {
287 /* Recursive subvolume destroy not allowed (yet?) */
288 ret = bch2_subvol_has_children(trans, inode_u->bi_subvol);
289 if (ret)
290 goto err;
291 }
292
293 if (deleting_subvol || inode_u->bi_subvol) {
294 ret = bch2_subvolume_unlink(trans, inode_u->bi_subvol);
295 if (ret)
296 goto err;
297
298 k = bch2_btree_iter_peek_slot(&dirent_iter);
299 ret = bkey_err(k);
300 if (ret)
301 goto err;
302
303 /*
304 * If we're deleting a subvolume, we need to really delete the
305 * dirent, not just emit a whiteout in the current snapshot:
306 */
307 bch2_btree_iter_set_snapshot(&dirent_iter, k.k->p.snapshot);
308 ret = bch2_btree_iter_traverse(&dirent_iter);
309 if (ret)
310 goto err;
311 } else {
312 bch2_inode_nlink_dec(trans, inode_u);
313 }
314
315 if (inode_u->bi_dir == dirent_iter.pos.inode &&
316 inode_u->bi_dir_offset == dirent_iter.pos.offset) {
317 inode_u->bi_dir = 0;
318 inode_u->bi_dir_offset = 0;
319 }
320
321 dir_u->bi_mtime = dir_u->bi_ctime = inode_u->bi_ctime = now;
322 dir_u->bi_nlink -= is_subdir_for_nlink(inode_u);
323
324 ret = bch2_hash_delete_at(trans, bch2_dirent_hash_desc,
325 &dir_hash, &dirent_iter,
326 BTREE_UPDATE_internal_snapshot_node) ?:
327 bch2_inode_write(trans, &dir_iter, dir_u) ?:
328 bch2_inode_write(trans, &inode_iter, inode_u);
329 err:
330 bch2_trans_iter_exit(trans, &inode_iter);
331 bch2_trans_iter_exit(trans, &dirent_iter);
332 bch2_trans_iter_exit(trans, &dir_iter);
333 return ret;
334 }
335
bch2_reinherit_attrs(struct bch_inode_unpacked * dst_u,struct bch_inode_unpacked * src_u)336 bool bch2_reinherit_attrs(struct bch_inode_unpacked *dst_u,
337 struct bch_inode_unpacked *src_u)
338 {
339 u64 src, dst;
340 unsigned id;
341 bool ret = false;
342
343 for (id = 0; id < Inode_opt_nr; id++) {
344 /* Skip attributes that were explicitly set on this inode */
345 if (dst_u->bi_fields_set & (1 << id))
346 continue;
347
348 src = bch2_inode_opt_get(src_u, id);
349 dst = bch2_inode_opt_get(dst_u, id);
350
351 if (src == dst)
352 continue;
353
354 bch2_inode_opt_set(dst_u, id, src);
355 ret = true;
356 }
357
358 return ret;
359 }
360
subvol_update_parent(struct btree_trans * trans,u32 subvol,u32 new_parent)361 static int subvol_update_parent(struct btree_trans *trans, u32 subvol, u32 new_parent)
362 {
363 struct btree_iter iter;
364 struct bkey_i_subvolume *s =
365 bch2_bkey_get_mut_typed(trans, &iter,
366 BTREE_ID_subvolumes, POS(0, subvol),
367 BTREE_ITER_cached, subvolume);
368 int ret = PTR_ERR_OR_ZERO(s);
369 if (ret)
370 return ret;
371
372 s->v.fs_path_parent = cpu_to_le32(new_parent);
373 bch2_trans_iter_exit(trans, &iter);
374 return 0;
375 }
376
bch2_rename_trans(struct btree_trans * trans,subvol_inum src_dir,struct bch_inode_unpacked * src_dir_u,subvol_inum dst_dir,struct bch_inode_unpacked * dst_dir_u,struct bch_inode_unpacked * src_inode_u,struct bch_inode_unpacked * dst_inode_u,const struct qstr * src_name,const struct qstr * dst_name,enum bch_rename_mode mode)377 int bch2_rename_trans(struct btree_trans *trans,
378 subvol_inum src_dir, struct bch_inode_unpacked *src_dir_u,
379 subvol_inum dst_dir, struct bch_inode_unpacked *dst_dir_u,
380 struct bch_inode_unpacked *src_inode_u,
381 struct bch_inode_unpacked *dst_inode_u,
382 const struct qstr *src_name,
383 const struct qstr *dst_name,
384 enum bch_rename_mode mode)
385 {
386 struct bch_fs *c = trans->c;
387 struct btree_iter src_dir_iter = { NULL };
388 struct btree_iter dst_dir_iter = { NULL };
389 struct btree_iter src_inode_iter = { NULL };
390 struct btree_iter dst_inode_iter = { NULL };
391 struct bch_hash_info src_hash, dst_hash;
392 subvol_inum src_inum, dst_inum;
393 u64 src_offset, dst_offset;
394 u64 now = bch2_current_time(c);
395 int ret;
396
397 ret = bch2_inode_peek(trans, &src_dir_iter, src_dir_u, src_dir,
398 BTREE_ITER_intent);
399 if (ret)
400 goto err;
401
402 src_hash = bch2_hash_info_init(c, src_dir_u);
403
404 if (dst_dir.inum != src_dir.inum ||
405 dst_dir.subvol != src_dir.subvol) {
406 ret = bch2_inode_peek(trans, &dst_dir_iter, dst_dir_u, dst_dir,
407 BTREE_ITER_intent);
408 if (ret)
409 goto err;
410
411 dst_hash = bch2_hash_info_init(c, dst_dir_u);
412 } else {
413 dst_dir_u = src_dir_u;
414 dst_hash = src_hash;
415 }
416
417 ret = bch2_dirent_rename(trans,
418 src_dir, &src_hash,
419 dst_dir, &dst_hash,
420 src_name, &src_inum, &src_offset,
421 dst_name, &dst_inum, &dst_offset,
422 mode);
423 if (ret)
424 goto err;
425
426 ret = bch2_inode_peek(trans, &src_inode_iter, src_inode_u, src_inum,
427 BTREE_ITER_intent);
428 if (ret)
429 goto err;
430
431 if (dst_inum.inum) {
432 ret = bch2_inode_peek(trans, &dst_inode_iter, dst_inode_u, dst_inum,
433 BTREE_ITER_intent);
434 if (ret)
435 goto err;
436 }
437
438 if (src_inode_u->bi_subvol &&
439 dst_dir.subvol != src_inode_u->bi_parent_subvol) {
440 ret = subvol_update_parent(trans, src_inode_u->bi_subvol, dst_dir.subvol);
441 if (ret)
442 goto err;
443 }
444
445 if (mode == BCH_RENAME_EXCHANGE &&
446 dst_inode_u->bi_subvol &&
447 src_dir.subvol != dst_inode_u->bi_parent_subvol) {
448 ret = subvol_update_parent(trans, dst_inode_u->bi_subvol, src_dir.subvol);
449 if (ret)
450 goto err;
451 }
452
453 /* Can't move across subvolumes, unless it's a subvolume root: */
454 if (src_dir.subvol != dst_dir.subvol &&
455 (!src_inode_u->bi_subvol ||
456 (dst_inum.inum && !dst_inode_u->bi_subvol))) {
457 ret = -EXDEV;
458 goto err;
459 }
460
461 if (src_inode_u->bi_parent_subvol)
462 src_inode_u->bi_parent_subvol = dst_dir.subvol;
463
464 if ((mode == BCH_RENAME_EXCHANGE) &&
465 dst_inode_u->bi_parent_subvol)
466 dst_inode_u->bi_parent_subvol = src_dir.subvol;
467
468 src_inode_u->bi_dir = dst_dir_u->bi_inum;
469 src_inode_u->bi_dir_offset = dst_offset;
470
471 if (mode == BCH_RENAME_EXCHANGE) {
472 dst_inode_u->bi_dir = src_dir_u->bi_inum;
473 dst_inode_u->bi_dir_offset = src_offset;
474 }
475
476 if (mode == BCH_RENAME_OVERWRITE &&
477 dst_inode_u->bi_dir == dst_dir_u->bi_inum &&
478 dst_inode_u->bi_dir_offset == src_offset) {
479 dst_inode_u->bi_dir = 0;
480 dst_inode_u->bi_dir_offset = 0;
481 }
482
483 if (mode == BCH_RENAME_OVERWRITE) {
484 if (S_ISDIR(src_inode_u->bi_mode) !=
485 S_ISDIR(dst_inode_u->bi_mode)) {
486 ret = -ENOTDIR;
487 goto err;
488 }
489
490 if (S_ISDIR(dst_inode_u->bi_mode)) {
491 ret = bch2_empty_dir_trans(trans, dst_inum);
492 if (ret)
493 goto err;
494 }
495 }
496
497 if (bch2_reinherit_attrs(src_inode_u, dst_dir_u) &&
498 S_ISDIR(src_inode_u->bi_mode)) {
499 ret = -EXDEV;
500 goto err;
501 }
502
503 if (mode == BCH_RENAME_EXCHANGE &&
504 bch2_reinherit_attrs(dst_inode_u, src_dir_u) &&
505 S_ISDIR(dst_inode_u->bi_mode)) {
506 ret = -EXDEV;
507 goto err;
508 }
509
510 if (is_subdir_for_nlink(src_inode_u)) {
511 src_dir_u->bi_nlink--;
512 dst_dir_u->bi_nlink++;
513 }
514
515 if (dst_inum.inum && is_subdir_for_nlink(dst_inode_u)) {
516 dst_dir_u->bi_nlink--;
517 src_dir_u->bi_nlink += mode == BCH_RENAME_EXCHANGE;
518 }
519
520 if (mode == BCH_RENAME_OVERWRITE)
521 bch2_inode_nlink_dec(trans, dst_inode_u);
522
523 src_dir_u->bi_mtime = now;
524 src_dir_u->bi_ctime = now;
525
526 if (src_dir.inum != dst_dir.inum) {
527 dst_dir_u->bi_mtime = now;
528 dst_dir_u->bi_ctime = now;
529 }
530
531 src_inode_u->bi_ctime = now;
532
533 if (dst_inum.inum)
534 dst_inode_u->bi_ctime = now;
535
536 ret = bch2_inode_write(trans, &src_dir_iter, src_dir_u) ?:
537 (src_dir.inum != dst_dir.inum
538 ? bch2_inode_write(trans, &dst_dir_iter, dst_dir_u)
539 : 0) ?:
540 bch2_inode_write(trans, &src_inode_iter, src_inode_u) ?:
541 (dst_inum.inum
542 ? bch2_inode_write(trans, &dst_inode_iter, dst_inode_u)
543 : 0);
544 err:
545 bch2_trans_iter_exit(trans, &dst_inode_iter);
546 bch2_trans_iter_exit(trans, &src_inode_iter);
547 bch2_trans_iter_exit(trans, &dst_dir_iter);
548 bch2_trans_iter_exit(trans, &src_dir_iter);
549 return ret;
550 }
551