xref: /linux/fs/bcachefs/fs.c (revision 2d7f3d1a5866705be2393150e1ffdf67030ab88d)
1 // SPDX-License-Identifier: GPL-2.0
2 #ifndef NO_BCACHEFS_FS
3 
4 #include "bcachefs.h"
5 #include "acl.h"
6 #include "bkey_buf.h"
7 #include "btree_update.h"
8 #include "buckets.h"
9 #include "chardev.h"
10 #include "dirent.h"
11 #include "errcode.h"
12 #include "extents.h"
13 #include "fs.h"
14 #include "fs-common.h"
15 #include "fs-io.h"
16 #include "fs-ioctl.h"
17 #include "fs-io-buffered.h"
18 #include "fs-io-direct.h"
19 #include "fs-io-pagecache.h"
20 #include "fsck.h"
21 #include "inode.h"
22 #include "io_read.h"
23 #include "journal.h"
24 #include "keylist.h"
25 #include "quota.h"
26 #include "snapshot.h"
27 #include "super.h"
28 #include "xattr.h"
29 
30 #include <linux/aio.h>
31 #include <linux/backing-dev.h>
32 #include <linux/exportfs.h>
33 #include <linux/fiemap.h>
34 #include <linux/module.h>
35 #include <linux/pagemap.h>
36 #include <linux/posix_acl.h>
37 #include <linux/random.h>
38 #include <linux/seq_file.h>
39 #include <linux/statfs.h>
40 #include <linux/string.h>
41 #include <linux/xattr.h>
42 
43 static struct kmem_cache *bch2_inode_cache;
44 
45 static void bch2_vfs_inode_init(struct btree_trans *, subvol_inum,
46 				struct bch_inode_info *,
47 				struct bch_inode_unpacked *,
48 				struct bch_subvolume *);
49 
50 void bch2_inode_update_after_write(struct btree_trans *trans,
51 				   struct bch_inode_info *inode,
52 				   struct bch_inode_unpacked *bi,
53 				   unsigned fields)
54 {
55 	struct bch_fs *c = trans->c;
56 
57 	BUG_ON(bi->bi_inum != inode->v.i_ino);
58 
59 	bch2_assert_pos_locked(trans, BTREE_ID_inodes,
60 			       POS(0, bi->bi_inum),
61 			       c->opts.inodes_use_key_cache);
62 
63 	set_nlink(&inode->v, bch2_inode_nlink_get(bi));
64 	i_uid_write(&inode->v, bi->bi_uid);
65 	i_gid_write(&inode->v, bi->bi_gid);
66 	inode->v.i_mode	= bi->bi_mode;
67 
68 	if (fields & ATTR_ATIME)
69 		inode_set_atime_to_ts(&inode->v, bch2_time_to_timespec(c, bi->bi_atime));
70 	if (fields & ATTR_MTIME)
71 		inode_set_mtime_to_ts(&inode->v, bch2_time_to_timespec(c, bi->bi_mtime));
72 	if (fields & ATTR_CTIME)
73 		inode_set_ctime_to_ts(&inode->v, bch2_time_to_timespec(c, bi->bi_ctime));
74 
75 	inode->ei_inode		= *bi;
76 
77 	bch2_inode_flags_to_vfs(inode);
78 }
79 
80 int __must_check bch2_write_inode(struct bch_fs *c,
81 				  struct bch_inode_info *inode,
82 				  inode_set_fn set,
83 				  void *p, unsigned fields)
84 {
85 	struct btree_trans *trans = bch2_trans_get(c);
86 	struct btree_iter iter = { NULL };
87 	struct bch_inode_unpacked inode_u;
88 	int ret;
89 retry:
90 	bch2_trans_begin(trans);
91 
92 	ret   = bch2_inode_peek(trans, &iter, &inode_u, inode_inum(inode),
93 				BTREE_ITER_INTENT) ?:
94 		(set ? set(trans, inode, &inode_u, p) : 0) ?:
95 		bch2_inode_write(trans, &iter, &inode_u) ?:
96 		bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc);
97 
98 	/*
99 	 * the btree node lock protects inode->ei_inode, not ei_update_lock;
100 	 * this is important for inode updates via bchfs_write_index_update
101 	 */
102 	if (!ret)
103 		bch2_inode_update_after_write(trans, inode, &inode_u, fields);
104 
105 	bch2_trans_iter_exit(trans, &iter);
106 
107 	if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
108 		goto retry;
109 
110 	bch2_fs_fatal_err_on(bch2_err_matches(ret, ENOENT), c,
111 			     "inode %u:%llu not found when updating",
112 			     inode_inum(inode).subvol,
113 			     inode_inum(inode).inum);
114 
115 	bch2_trans_put(trans);
116 	return ret < 0 ? ret : 0;
117 }
118 
119 int bch2_fs_quota_transfer(struct bch_fs *c,
120 			   struct bch_inode_info *inode,
121 			   struct bch_qid new_qid,
122 			   unsigned qtypes,
123 			   enum quota_acct_mode mode)
124 {
125 	unsigned i;
126 	int ret;
127 
128 	qtypes &= enabled_qtypes(c);
129 
130 	for (i = 0; i < QTYP_NR; i++)
131 		if (new_qid.q[i] == inode->ei_qid.q[i])
132 			qtypes &= ~(1U << i);
133 
134 	if (!qtypes)
135 		return 0;
136 
137 	mutex_lock(&inode->ei_quota_lock);
138 
139 	ret = bch2_quota_transfer(c, qtypes, new_qid,
140 				  inode->ei_qid,
141 				  inode->v.i_blocks +
142 				  inode->ei_quota_reserved,
143 				  mode);
144 	if (!ret)
145 		for (i = 0; i < QTYP_NR; i++)
146 			if (qtypes & (1 << i))
147 				inode->ei_qid.q[i] = new_qid.q[i];
148 
149 	mutex_unlock(&inode->ei_quota_lock);
150 
151 	return ret;
152 }
153 
154 static int bch2_iget5_test(struct inode *vinode, void *p)
155 {
156 	struct bch_inode_info *inode = to_bch_ei(vinode);
157 	subvol_inum *inum = p;
158 
159 	return inode->ei_subvol == inum->subvol &&
160 		inode->ei_inode.bi_inum == inum->inum;
161 }
162 
163 static int bch2_iget5_set(struct inode *vinode, void *p)
164 {
165 	struct bch_inode_info *inode = to_bch_ei(vinode);
166 	subvol_inum *inum = p;
167 
168 	inode->v.i_ino		= inum->inum;
169 	inode->ei_subvol	= inum->subvol;
170 	inode->ei_inode.bi_inum	= inum->inum;
171 	return 0;
172 }
173 
174 static unsigned bch2_inode_hash(subvol_inum inum)
175 {
176 	return jhash_3words(inum.subvol, inum.inum >> 32, inum.inum, JHASH_INITVAL);
177 }
178 
179 struct inode *bch2_vfs_inode_get(struct bch_fs *c, subvol_inum inum)
180 {
181 	struct bch_inode_unpacked inode_u;
182 	struct bch_inode_info *inode;
183 	struct btree_trans *trans;
184 	struct bch_subvolume subvol;
185 	int ret;
186 
187 	inode = to_bch_ei(iget5_locked(c->vfs_sb,
188 				       bch2_inode_hash(inum),
189 				       bch2_iget5_test,
190 				       bch2_iget5_set,
191 				       &inum));
192 	if (unlikely(!inode))
193 		return ERR_PTR(-ENOMEM);
194 	if (!(inode->v.i_state & I_NEW))
195 		return &inode->v;
196 
197 	trans = bch2_trans_get(c);
198 	ret = lockrestart_do(trans,
199 		bch2_subvolume_get(trans, inum.subvol, true, 0, &subvol) ?:
200 		bch2_inode_find_by_inum_trans(trans, inum, &inode_u));
201 
202 	if (!ret)
203 		bch2_vfs_inode_init(trans, inum, inode, &inode_u, &subvol);
204 	bch2_trans_put(trans);
205 
206 	if (ret) {
207 		iget_failed(&inode->v);
208 		return ERR_PTR(bch2_err_class(ret));
209 	}
210 
211 	mutex_lock(&c->vfs_inodes_lock);
212 	list_add(&inode->ei_vfs_inode_list, &c->vfs_inodes_list);
213 	mutex_unlock(&c->vfs_inodes_lock);
214 
215 	unlock_new_inode(&inode->v);
216 
217 	return &inode->v;
218 }
219 
220 struct bch_inode_info *
221 __bch2_create(struct mnt_idmap *idmap,
222 	      struct bch_inode_info *dir, struct dentry *dentry,
223 	      umode_t mode, dev_t rdev, subvol_inum snapshot_src,
224 	      unsigned flags)
225 {
226 	struct bch_fs *c = dir->v.i_sb->s_fs_info;
227 	struct btree_trans *trans;
228 	struct bch_inode_unpacked dir_u;
229 	struct bch_inode_info *inode, *old;
230 	struct bch_inode_unpacked inode_u;
231 	struct posix_acl *default_acl = NULL, *acl = NULL;
232 	subvol_inum inum;
233 	struct bch_subvolume subvol;
234 	u64 journal_seq = 0;
235 	int ret;
236 
237 	/*
238 	 * preallocate acls + vfs inode before btree transaction, so that
239 	 * nothing can fail after the transaction succeeds:
240 	 */
241 #ifdef CONFIG_BCACHEFS_POSIX_ACL
242 	ret = posix_acl_create(&dir->v, &mode, &default_acl, &acl);
243 	if (ret)
244 		return ERR_PTR(ret);
245 #endif
246 	inode = to_bch_ei(new_inode(c->vfs_sb));
247 	if (unlikely(!inode)) {
248 		inode = ERR_PTR(-ENOMEM);
249 		goto err;
250 	}
251 
252 	bch2_inode_init_early(c, &inode_u);
253 
254 	if (!(flags & BCH_CREATE_TMPFILE))
255 		mutex_lock(&dir->ei_update_lock);
256 
257 	trans = bch2_trans_get(c);
258 retry:
259 	bch2_trans_begin(trans);
260 
261 	ret   = bch2_subvol_is_ro_trans(trans, dir->ei_subvol) ?:
262 		bch2_create_trans(trans,
263 				  inode_inum(dir), &dir_u, &inode_u,
264 				  !(flags & BCH_CREATE_TMPFILE)
265 				  ? &dentry->d_name : NULL,
266 				  from_kuid(i_user_ns(&dir->v), current_fsuid()),
267 				  from_kgid(i_user_ns(&dir->v), current_fsgid()),
268 				  mode, rdev,
269 				  default_acl, acl, snapshot_src, flags) ?:
270 		bch2_quota_acct(c, bch_qid(&inode_u), Q_INO, 1,
271 				KEY_TYPE_QUOTA_PREALLOC);
272 	if (unlikely(ret))
273 		goto err_before_quota;
274 
275 	inum.subvol = inode_u.bi_subvol ?: dir->ei_subvol;
276 	inum.inum = inode_u.bi_inum;
277 
278 	ret   = bch2_subvolume_get(trans, inum.subvol, true,
279 				   BTREE_ITER_WITH_UPDATES, &subvol) ?:
280 		bch2_trans_commit(trans, NULL, &journal_seq, 0);
281 	if (unlikely(ret)) {
282 		bch2_quota_acct(c, bch_qid(&inode_u), Q_INO, -1,
283 				KEY_TYPE_QUOTA_WARN);
284 err_before_quota:
285 		if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
286 			goto retry;
287 		goto err_trans;
288 	}
289 
290 	if (!(flags & BCH_CREATE_TMPFILE)) {
291 		bch2_inode_update_after_write(trans, dir, &dir_u,
292 					      ATTR_MTIME|ATTR_CTIME);
293 		mutex_unlock(&dir->ei_update_lock);
294 	}
295 
296 	bch2_iget5_set(&inode->v, &inum);
297 	bch2_vfs_inode_init(trans, inum, inode, &inode_u, &subvol);
298 
299 	set_cached_acl(&inode->v, ACL_TYPE_ACCESS, acl);
300 	set_cached_acl(&inode->v, ACL_TYPE_DEFAULT, default_acl);
301 
302 	/*
303 	 * we must insert the new inode into the inode cache before calling
304 	 * bch2_trans_exit() and dropping locks, else we could race with another
305 	 * thread pulling the inode in and modifying it:
306 	 */
307 
308 	inode->v.i_state |= I_CREATING;
309 
310 	old = to_bch_ei(inode_insert5(&inode->v,
311 				      bch2_inode_hash(inum),
312 				      bch2_iget5_test,
313 				      bch2_iget5_set,
314 				      &inum));
315 	BUG_ON(!old);
316 
317 	if (unlikely(old != inode)) {
318 		/*
319 		 * We raced, another process pulled the new inode into cache
320 		 * before us:
321 		 */
322 		make_bad_inode(&inode->v);
323 		iput(&inode->v);
324 
325 		inode = old;
326 	} else {
327 		mutex_lock(&c->vfs_inodes_lock);
328 		list_add(&inode->ei_vfs_inode_list, &c->vfs_inodes_list);
329 		mutex_unlock(&c->vfs_inodes_lock);
330 		/*
331 		 * we really don't want insert_inode_locked2() to be setting
332 		 * I_NEW...
333 		 */
334 		unlock_new_inode(&inode->v);
335 	}
336 
337 	bch2_trans_put(trans);
338 err:
339 	posix_acl_release(default_acl);
340 	posix_acl_release(acl);
341 	return inode;
342 err_trans:
343 	if (!(flags & BCH_CREATE_TMPFILE))
344 		mutex_unlock(&dir->ei_update_lock);
345 
346 	bch2_trans_put(trans);
347 	make_bad_inode(&inode->v);
348 	iput(&inode->v);
349 	inode = ERR_PTR(ret);
350 	goto err;
351 }
352 
353 /* methods */
354 
355 static struct dentry *bch2_lookup(struct inode *vdir, struct dentry *dentry,
356 				  unsigned int flags)
357 {
358 	struct bch_fs *c = vdir->i_sb->s_fs_info;
359 	struct bch_inode_info *dir = to_bch_ei(vdir);
360 	struct bch_hash_info hash = bch2_hash_info_init(c, &dir->ei_inode);
361 	struct inode *vinode = NULL;
362 	subvol_inum inum = { .subvol = 1 };
363 	int ret;
364 
365 	ret = bch2_dirent_lookup(c, inode_inum(dir), &hash,
366 				 &dentry->d_name, &inum);
367 
368 	if (!ret)
369 		vinode = bch2_vfs_inode_get(c, inum);
370 
371 	return d_splice_alias(vinode, dentry);
372 }
373 
374 static int bch2_mknod(struct mnt_idmap *idmap,
375 		      struct inode *vdir, struct dentry *dentry,
376 		      umode_t mode, dev_t rdev)
377 {
378 	struct bch_inode_info *inode =
379 		__bch2_create(idmap, to_bch_ei(vdir), dentry, mode, rdev,
380 			      (subvol_inum) { 0 }, 0);
381 
382 	if (IS_ERR(inode))
383 		return bch2_err_class(PTR_ERR(inode));
384 
385 	d_instantiate(dentry, &inode->v);
386 	return 0;
387 }
388 
389 static int bch2_create(struct mnt_idmap *idmap,
390 		       struct inode *vdir, struct dentry *dentry,
391 		       umode_t mode, bool excl)
392 {
393 	return bch2_mknod(idmap, vdir, dentry, mode|S_IFREG, 0);
394 }
395 
396 static int __bch2_link(struct bch_fs *c,
397 		       struct bch_inode_info *inode,
398 		       struct bch_inode_info *dir,
399 		       struct dentry *dentry)
400 {
401 	struct btree_trans *trans = bch2_trans_get(c);
402 	struct bch_inode_unpacked dir_u, inode_u;
403 	int ret;
404 
405 	mutex_lock(&inode->ei_update_lock);
406 
407 	ret = commit_do(trans, NULL, NULL, 0,
408 			bch2_link_trans(trans,
409 					inode_inum(dir),   &dir_u,
410 					inode_inum(inode), &inode_u,
411 					&dentry->d_name));
412 
413 	if (likely(!ret)) {
414 		bch2_inode_update_after_write(trans, dir, &dir_u,
415 					      ATTR_MTIME|ATTR_CTIME);
416 		bch2_inode_update_after_write(trans, inode, &inode_u, ATTR_CTIME);
417 	}
418 
419 	bch2_trans_put(trans);
420 	mutex_unlock(&inode->ei_update_lock);
421 	return ret;
422 }
423 
424 static int bch2_link(struct dentry *old_dentry, struct inode *vdir,
425 		     struct dentry *dentry)
426 {
427 	struct bch_fs *c = vdir->i_sb->s_fs_info;
428 	struct bch_inode_info *dir = to_bch_ei(vdir);
429 	struct bch_inode_info *inode = to_bch_ei(old_dentry->d_inode);
430 	int ret;
431 
432 	lockdep_assert_held(&inode->v.i_rwsem);
433 
434 	ret   = bch2_subvol_is_ro(c, dir->ei_subvol) ?:
435 		bch2_subvol_is_ro(c, inode->ei_subvol) ?:
436 		__bch2_link(c, inode, dir, dentry);
437 	if (unlikely(ret))
438 		return bch2_err_class(ret);
439 
440 	ihold(&inode->v);
441 	d_instantiate(dentry, &inode->v);
442 	return 0;
443 }
444 
445 int __bch2_unlink(struct inode *vdir, struct dentry *dentry,
446 		  bool deleting_snapshot)
447 {
448 	struct bch_fs *c = vdir->i_sb->s_fs_info;
449 	struct bch_inode_info *dir = to_bch_ei(vdir);
450 	struct bch_inode_info *inode = to_bch_ei(dentry->d_inode);
451 	struct bch_inode_unpacked dir_u, inode_u;
452 	struct btree_trans *trans = bch2_trans_get(c);
453 	int ret;
454 
455 	bch2_lock_inodes(INODE_UPDATE_LOCK, dir, inode);
456 
457 	ret = commit_do(trans, NULL, NULL,
458 			BCH_TRANS_COMMIT_no_enospc,
459 		bch2_unlink_trans(trans,
460 				  inode_inum(dir), &dir_u,
461 				  &inode_u, &dentry->d_name,
462 				  deleting_snapshot));
463 	if (unlikely(ret))
464 		goto err;
465 
466 	bch2_inode_update_after_write(trans, dir, &dir_u,
467 				      ATTR_MTIME|ATTR_CTIME);
468 	bch2_inode_update_after_write(trans, inode, &inode_u,
469 				      ATTR_MTIME);
470 
471 	if (inode_u.bi_subvol) {
472 		/*
473 		 * Subvolume deletion is asynchronous, but we still want to tell
474 		 * the VFS that it's been deleted here:
475 		 */
476 		set_nlink(&inode->v, 0);
477 	}
478 err:
479 	bch2_unlock_inodes(INODE_UPDATE_LOCK, dir, inode);
480 	bch2_trans_put(trans);
481 
482 	return ret;
483 }
484 
485 static int bch2_unlink(struct inode *vdir, struct dentry *dentry)
486 {
487 	struct bch_inode_info *dir= to_bch_ei(vdir);
488 	struct bch_fs *c = dir->v.i_sb->s_fs_info;
489 
490 	int ret = bch2_subvol_is_ro(c, dir->ei_subvol) ?:
491 		__bch2_unlink(vdir, dentry, false);
492 	return bch2_err_class(ret);
493 }
494 
495 static int bch2_symlink(struct mnt_idmap *idmap,
496 			struct inode *vdir, struct dentry *dentry,
497 			const char *symname)
498 {
499 	struct bch_fs *c = vdir->i_sb->s_fs_info;
500 	struct bch_inode_info *dir = to_bch_ei(vdir), *inode;
501 	int ret;
502 
503 	inode = __bch2_create(idmap, dir, dentry, S_IFLNK|S_IRWXUGO, 0,
504 			      (subvol_inum) { 0 }, BCH_CREATE_TMPFILE);
505 	if (IS_ERR(inode))
506 		return bch2_err_class(PTR_ERR(inode));
507 
508 	inode_lock(&inode->v);
509 	ret = page_symlink(&inode->v, symname, strlen(symname) + 1);
510 	inode_unlock(&inode->v);
511 
512 	if (unlikely(ret))
513 		goto err;
514 
515 	ret = filemap_write_and_wait_range(inode->v.i_mapping, 0, LLONG_MAX);
516 	if (unlikely(ret))
517 		goto err;
518 
519 	ret = __bch2_link(c, inode, dir, dentry);
520 	if (unlikely(ret))
521 		goto err;
522 
523 	d_instantiate(dentry, &inode->v);
524 	return 0;
525 err:
526 	iput(&inode->v);
527 	return bch2_err_class(ret);
528 }
529 
530 static int bch2_mkdir(struct mnt_idmap *idmap,
531 		      struct inode *vdir, struct dentry *dentry, umode_t mode)
532 {
533 	return bch2_mknod(idmap, vdir, dentry, mode|S_IFDIR, 0);
534 }
535 
536 static int bch2_rename2(struct mnt_idmap *idmap,
537 			struct inode *src_vdir, struct dentry *src_dentry,
538 			struct inode *dst_vdir, struct dentry *dst_dentry,
539 			unsigned flags)
540 {
541 	struct bch_fs *c = src_vdir->i_sb->s_fs_info;
542 	struct bch_inode_info *src_dir = to_bch_ei(src_vdir);
543 	struct bch_inode_info *dst_dir = to_bch_ei(dst_vdir);
544 	struct bch_inode_info *src_inode = to_bch_ei(src_dentry->d_inode);
545 	struct bch_inode_info *dst_inode = to_bch_ei(dst_dentry->d_inode);
546 	struct bch_inode_unpacked dst_dir_u, src_dir_u;
547 	struct bch_inode_unpacked src_inode_u, dst_inode_u;
548 	struct btree_trans *trans;
549 	enum bch_rename_mode mode = flags & RENAME_EXCHANGE
550 		? BCH_RENAME_EXCHANGE
551 		: dst_dentry->d_inode
552 		? BCH_RENAME_OVERWRITE : BCH_RENAME;
553 	int ret;
554 
555 	if (flags & ~(RENAME_NOREPLACE|RENAME_EXCHANGE))
556 		return -EINVAL;
557 
558 	if (mode == BCH_RENAME_OVERWRITE) {
559 		ret = filemap_write_and_wait_range(src_inode->v.i_mapping,
560 						   0, LLONG_MAX);
561 		if (ret)
562 			return ret;
563 	}
564 
565 	trans = bch2_trans_get(c);
566 
567 	bch2_lock_inodes(INODE_UPDATE_LOCK,
568 			 src_dir,
569 			 dst_dir,
570 			 src_inode,
571 			 dst_inode);
572 
573 	ret   = bch2_subvol_is_ro_trans(trans, src_dir->ei_subvol) ?:
574 		bch2_subvol_is_ro_trans(trans, dst_dir->ei_subvol);
575 	if (ret)
576 		goto err;
577 
578 	if (inode_attr_changing(dst_dir, src_inode, Inode_opt_project)) {
579 		ret = bch2_fs_quota_transfer(c, src_inode,
580 					     dst_dir->ei_qid,
581 					     1 << QTYP_PRJ,
582 					     KEY_TYPE_QUOTA_PREALLOC);
583 		if (ret)
584 			goto err;
585 	}
586 
587 	if (mode == BCH_RENAME_EXCHANGE &&
588 	    inode_attr_changing(src_dir, dst_inode, Inode_opt_project)) {
589 		ret = bch2_fs_quota_transfer(c, dst_inode,
590 					     src_dir->ei_qid,
591 					     1 << QTYP_PRJ,
592 					     KEY_TYPE_QUOTA_PREALLOC);
593 		if (ret)
594 			goto err;
595 	}
596 
597 	ret = commit_do(trans, NULL, NULL, 0,
598 			bch2_rename_trans(trans,
599 					  inode_inum(src_dir), &src_dir_u,
600 					  inode_inum(dst_dir), &dst_dir_u,
601 					  &src_inode_u,
602 					  &dst_inode_u,
603 					  &src_dentry->d_name,
604 					  &dst_dentry->d_name,
605 					  mode));
606 	if (unlikely(ret))
607 		goto err;
608 
609 	BUG_ON(src_inode->v.i_ino != src_inode_u.bi_inum);
610 	BUG_ON(dst_inode &&
611 	       dst_inode->v.i_ino != dst_inode_u.bi_inum);
612 
613 	bch2_inode_update_after_write(trans, src_dir, &src_dir_u,
614 				      ATTR_MTIME|ATTR_CTIME);
615 
616 	if (src_dir != dst_dir)
617 		bch2_inode_update_after_write(trans, dst_dir, &dst_dir_u,
618 					      ATTR_MTIME|ATTR_CTIME);
619 
620 	bch2_inode_update_after_write(trans, src_inode, &src_inode_u,
621 				      ATTR_CTIME);
622 
623 	if (dst_inode)
624 		bch2_inode_update_after_write(trans, dst_inode, &dst_inode_u,
625 					      ATTR_CTIME);
626 err:
627 	bch2_trans_put(trans);
628 
629 	bch2_fs_quota_transfer(c, src_inode,
630 			       bch_qid(&src_inode->ei_inode),
631 			       1 << QTYP_PRJ,
632 			       KEY_TYPE_QUOTA_NOCHECK);
633 	if (dst_inode)
634 		bch2_fs_quota_transfer(c, dst_inode,
635 				       bch_qid(&dst_inode->ei_inode),
636 				       1 << QTYP_PRJ,
637 				       KEY_TYPE_QUOTA_NOCHECK);
638 
639 	bch2_unlock_inodes(INODE_UPDATE_LOCK,
640 			   src_dir,
641 			   dst_dir,
642 			   src_inode,
643 			   dst_inode);
644 
645 	return bch2_err_class(ret);
646 }
647 
648 static void bch2_setattr_copy(struct mnt_idmap *idmap,
649 			      struct bch_inode_info *inode,
650 			      struct bch_inode_unpacked *bi,
651 			      struct iattr *attr)
652 {
653 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
654 	unsigned int ia_valid = attr->ia_valid;
655 
656 	if (ia_valid & ATTR_UID)
657 		bi->bi_uid = from_kuid(i_user_ns(&inode->v), attr->ia_uid);
658 	if (ia_valid & ATTR_GID)
659 		bi->bi_gid = from_kgid(i_user_ns(&inode->v), attr->ia_gid);
660 
661 	if (ia_valid & ATTR_SIZE)
662 		bi->bi_size = attr->ia_size;
663 
664 	if (ia_valid & ATTR_ATIME)
665 		bi->bi_atime = timespec_to_bch2_time(c, attr->ia_atime);
666 	if (ia_valid & ATTR_MTIME)
667 		bi->bi_mtime = timespec_to_bch2_time(c, attr->ia_mtime);
668 	if (ia_valid & ATTR_CTIME)
669 		bi->bi_ctime = timespec_to_bch2_time(c, attr->ia_ctime);
670 
671 	if (ia_valid & ATTR_MODE) {
672 		umode_t mode = attr->ia_mode;
673 		kgid_t gid = ia_valid & ATTR_GID
674 			? attr->ia_gid
675 			: inode->v.i_gid;
676 
677 		if (!in_group_p(gid) &&
678 		    !capable_wrt_inode_uidgid(idmap, &inode->v, CAP_FSETID))
679 			mode &= ~S_ISGID;
680 		bi->bi_mode = mode;
681 	}
682 }
683 
684 int bch2_setattr_nonsize(struct mnt_idmap *idmap,
685 			 struct bch_inode_info *inode,
686 			 struct iattr *attr)
687 {
688 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
689 	struct bch_qid qid;
690 	struct btree_trans *trans;
691 	struct btree_iter inode_iter = { NULL };
692 	struct bch_inode_unpacked inode_u;
693 	struct posix_acl *acl = NULL;
694 	int ret;
695 
696 	mutex_lock(&inode->ei_update_lock);
697 
698 	qid = inode->ei_qid;
699 
700 	if (attr->ia_valid & ATTR_UID)
701 		qid.q[QTYP_USR] = from_kuid(i_user_ns(&inode->v), attr->ia_uid);
702 
703 	if (attr->ia_valid & ATTR_GID)
704 		qid.q[QTYP_GRP] = from_kgid(i_user_ns(&inode->v), attr->ia_gid);
705 
706 	ret = bch2_fs_quota_transfer(c, inode, qid, ~0,
707 				     KEY_TYPE_QUOTA_PREALLOC);
708 	if (ret)
709 		goto err;
710 
711 	trans = bch2_trans_get(c);
712 retry:
713 	bch2_trans_begin(trans);
714 	kfree(acl);
715 	acl = NULL;
716 
717 	ret = bch2_inode_peek(trans, &inode_iter, &inode_u, inode_inum(inode),
718 			      BTREE_ITER_INTENT);
719 	if (ret)
720 		goto btree_err;
721 
722 	bch2_setattr_copy(idmap, inode, &inode_u, attr);
723 
724 	if (attr->ia_valid & ATTR_MODE) {
725 		ret = bch2_acl_chmod(trans, inode_inum(inode), &inode_u,
726 				     inode_u.bi_mode, &acl);
727 		if (ret)
728 			goto btree_err;
729 	}
730 
731 	ret =   bch2_inode_write(trans, &inode_iter, &inode_u) ?:
732 		bch2_trans_commit(trans, NULL, NULL,
733 				  BCH_TRANS_COMMIT_no_enospc);
734 btree_err:
735 	bch2_trans_iter_exit(trans, &inode_iter);
736 
737 	if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
738 		goto retry;
739 	if (unlikely(ret))
740 		goto err_trans;
741 
742 	bch2_inode_update_after_write(trans, inode, &inode_u, attr->ia_valid);
743 
744 	if (acl)
745 		set_cached_acl(&inode->v, ACL_TYPE_ACCESS, acl);
746 err_trans:
747 	bch2_trans_put(trans);
748 err:
749 	mutex_unlock(&inode->ei_update_lock);
750 
751 	return bch2_err_class(ret);
752 }
753 
754 static int bch2_getattr(struct mnt_idmap *idmap,
755 			const struct path *path, struct kstat *stat,
756 			u32 request_mask, unsigned query_flags)
757 {
758 	struct bch_inode_info *inode = to_bch_ei(d_inode(path->dentry));
759 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
760 
761 	stat->dev	= inode->v.i_sb->s_dev;
762 	stat->ino	= inode->v.i_ino;
763 	stat->mode	= inode->v.i_mode;
764 	stat->nlink	= inode->v.i_nlink;
765 	stat->uid	= inode->v.i_uid;
766 	stat->gid	= inode->v.i_gid;
767 	stat->rdev	= inode->v.i_rdev;
768 	stat->size	= i_size_read(&inode->v);
769 	stat->atime	= inode_get_atime(&inode->v);
770 	stat->mtime	= inode_get_mtime(&inode->v);
771 	stat->ctime	= inode_get_ctime(&inode->v);
772 	stat->blksize	= block_bytes(c);
773 	stat->blocks	= inode->v.i_blocks;
774 
775 	if (request_mask & STATX_BTIME) {
776 		stat->result_mask |= STATX_BTIME;
777 		stat->btime = bch2_time_to_timespec(c, inode->ei_inode.bi_otime);
778 	}
779 
780 	if (inode->ei_inode.bi_flags & BCH_INODE_immutable)
781 		stat->attributes |= STATX_ATTR_IMMUTABLE;
782 	stat->attributes_mask	 |= STATX_ATTR_IMMUTABLE;
783 
784 	if (inode->ei_inode.bi_flags & BCH_INODE_append)
785 		stat->attributes |= STATX_ATTR_APPEND;
786 	stat->attributes_mask	 |= STATX_ATTR_APPEND;
787 
788 	if (inode->ei_inode.bi_flags & BCH_INODE_nodump)
789 		stat->attributes |= STATX_ATTR_NODUMP;
790 	stat->attributes_mask	 |= STATX_ATTR_NODUMP;
791 
792 	return 0;
793 }
794 
795 static int bch2_setattr(struct mnt_idmap *idmap,
796 			struct dentry *dentry, struct iattr *iattr)
797 {
798 	struct bch_inode_info *inode = to_bch_ei(dentry->d_inode);
799 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
800 	int ret;
801 
802 	lockdep_assert_held(&inode->v.i_rwsem);
803 
804 	ret   = bch2_subvol_is_ro(c, inode->ei_subvol) ?:
805 		setattr_prepare(idmap, dentry, iattr);
806 	if (ret)
807 		return ret;
808 
809 	return iattr->ia_valid & ATTR_SIZE
810 		? bchfs_truncate(idmap, inode, iattr)
811 		: bch2_setattr_nonsize(idmap, inode, iattr);
812 }
813 
814 static int bch2_tmpfile(struct mnt_idmap *idmap,
815 			struct inode *vdir, struct file *file, umode_t mode)
816 {
817 	struct bch_inode_info *inode =
818 		__bch2_create(idmap, to_bch_ei(vdir),
819 			      file->f_path.dentry, mode, 0,
820 			      (subvol_inum) { 0 }, BCH_CREATE_TMPFILE);
821 
822 	if (IS_ERR(inode))
823 		return bch2_err_class(PTR_ERR(inode));
824 
825 	d_mark_tmpfile(file, &inode->v);
826 	d_instantiate(file->f_path.dentry, &inode->v);
827 	return finish_open_simple(file, 0);
828 }
829 
830 static int bch2_fill_extent(struct bch_fs *c,
831 			    struct fiemap_extent_info *info,
832 			    struct bkey_s_c k, unsigned flags)
833 {
834 	if (bkey_extent_is_direct_data(k.k)) {
835 		struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
836 		const union bch_extent_entry *entry;
837 		struct extent_ptr_decoded p;
838 		int ret;
839 
840 		if (k.k->type == KEY_TYPE_reflink_v)
841 			flags |= FIEMAP_EXTENT_SHARED;
842 
843 		bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
844 			int flags2 = 0;
845 			u64 offset = p.ptr.offset;
846 
847 			if (p.ptr.unwritten)
848 				flags2 |= FIEMAP_EXTENT_UNWRITTEN;
849 
850 			if (p.crc.compression_type)
851 				flags2 |= FIEMAP_EXTENT_ENCODED;
852 			else
853 				offset += p.crc.offset;
854 
855 			if ((offset & (block_sectors(c) - 1)) ||
856 			    (k.k->size & (block_sectors(c) - 1)))
857 				flags2 |= FIEMAP_EXTENT_NOT_ALIGNED;
858 
859 			ret = fiemap_fill_next_extent(info,
860 						bkey_start_offset(k.k) << 9,
861 						offset << 9,
862 						k.k->size << 9, flags|flags2);
863 			if (ret)
864 				return ret;
865 		}
866 
867 		return 0;
868 	} else if (bkey_extent_is_inline_data(k.k)) {
869 		return fiemap_fill_next_extent(info,
870 					       bkey_start_offset(k.k) << 9,
871 					       0, k.k->size << 9,
872 					       flags|
873 					       FIEMAP_EXTENT_DATA_INLINE);
874 	} else if (k.k->type == KEY_TYPE_reservation) {
875 		return fiemap_fill_next_extent(info,
876 					       bkey_start_offset(k.k) << 9,
877 					       0, k.k->size << 9,
878 					       flags|
879 					       FIEMAP_EXTENT_DELALLOC|
880 					       FIEMAP_EXTENT_UNWRITTEN);
881 	} else {
882 		BUG();
883 	}
884 }
885 
886 static int bch2_fiemap(struct inode *vinode, struct fiemap_extent_info *info,
887 		       u64 start, u64 len)
888 {
889 	struct bch_fs *c = vinode->i_sb->s_fs_info;
890 	struct bch_inode_info *ei = to_bch_ei(vinode);
891 	struct btree_trans *trans;
892 	struct btree_iter iter;
893 	struct bkey_s_c k;
894 	struct bkey_buf cur, prev;
895 	struct bpos end = POS(ei->v.i_ino, (start + len) >> 9);
896 	unsigned offset_into_extent, sectors;
897 	bool have_extent = false;
898 	u32 snapshot;
899 	int ret = 0;
900 
901 	ret = fiemap_prep(&ei->v, info, start, &len, FIEMAP_FLAG_SYNC);
902 	if (ret)
903 		return ret;
904 
905 	if (start + len < start)
906 		return -EINVAL;
907 
908 	start >>= 9;
909 
910 	bch2_bkey_buf_init(&cur);
911 	bch2_bkey_buf_init(&prev);
912 	trans = bch2_trans_get(c);
913 retry:
914 	bch2_trans_begin(trans);
915 
916 	ret = bch2_subvolume_get_snapshot(trans, ei->ei_subvol, &snapshot);
917 	if (ret)
918 		goto err;
919 
920 	bch2_trans_iter_init(trans, &iter, BTREE_ID_extents,
921 			     SPOS(ei->v.i_ino, start, snapshot), 0);
922 
923 	while (!(ret = btree_trans_too_many_iters(trans)) &&
924 	       (k = bch2_btree_iter_peek_upto(&iter, end)).k &&
925 	       !(ret = bkey_err(k))) {
926 		enum btree_id data_btree = BTREE_ID_extents;
927 
928 		if (!bkey_extent_is_data(k.k) &&
929 		    k.k->type != KEY_TYPE_reservation) {
930 			bch2_btree_iter_advance(&iter);
931 			continue;
932 		}
933 
934 		offset_into_extent	= iter.pos.offset -
935 			bkey_start_offset(k.k);
936 		sectors			= k.k->size - offset_into_extent;
937 
938 		bch2_bkey_buf_reassemble(&cur, c, k);
939 
940 		ret = bch2_read_indirect_extent(trans, &data_btree,
941 					&offset_into_extent, &cur);
942 		if (ret)
943 			break;
944 
945 		k = bkey_i_to_s_c(cur.k);
946 		bch2_bkey_buf_realloc(&prev, c, k.k->u64s);
947 
948 		sectors = min(sectors, k.k->size - offset_into_extent);
949 
950 		bch2_cut_front(POS(k.k->p.inode,
951 				   bkey_start_offset(k.k) +
952 				   offset_into_extent),
953 			       cur.k);
954 		bch2_key_resize(&cur.k->k, sectors);
955 		cur.k->k.p = iter.pos;
956 		cur.k->k.p.offset += cur.k->k.size;
957 
958 		if (have_extent) {
959 			bch2_trans_unlock(trans);
960 			ret = bch2_fill_extent(c, info,
961 					bkey_i_to_s_c(prev.k), 0);
962 			if (ret)
963 				break;
964 		}
965 
966 		bkey_copy(prev.k, cur.k);
967 		have_extent = true;
968 
969 		bch2_btree_iter_set_pos(&iter,
970 			POS(iter.pos.inode, iter.pos.offset + sectors));
971 	}
972 	start = iter.pos.offset;
973 	bch2_trans_iter_exit(trans, &iter);
974 err:
975 	if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
976 		goto retry;
977 
978 	if (!ret && have_extent) {
979 		bch2_trans_unlock(trans);
980 		ret = bch2_fill_extent(c, info, bkey_i_to_s_c(prev.k),
981 				       FIEMAP_EXTENT_LAST);
982 	}
983 
984 	bch2_trans_put(trans);
985 	bch2_bkey_buf_exit(&cur, c);
986 	bch2_bkey_buf_exit(&prev, c);
987 	return ret < 0 ? ret : 0;
988 }
989 
990 static const struct vm_operations_struct bch_vm_ops = {
991 	.fault		= bch2_page_fault,
992 	.map_pages	= filemap_map_pages,
993 	.page_mkwrite   = bch2_page_mkwrite,
994 };
995 
996 static int bch2_mmap(struct file *file, struct vm_area_struct *vma)
997 {
998 	file_accessed(file);
999 
1000 	vma->vm_ops = &bch_vm_ops;
1001 	return 0;
1002 }
1003 
1004 /* Directories: */
1005 
1006 static loff_t bch2_dir_llseek(struct file *file, loff_t offset, int whence)
1007 {
1008 	return generic_file_llseek_size(file, offset, whence,
1009 					S64_MAX, S64_MAX);
1010 }
1011 
1012 static int bch2_vfs_readdir(struct file *file, struct dir_context *ctx)
1013 {
1014 	struct bch_inode_info *inode = file_bch_inode(file);
1015 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
1016 
1017 	if (!dir_emit_dots(file, ctx))
1018 		return 0;
1019 
1020 	int ret = bch2_readdir(c, inode_inum(inode), ctx);
1021 
1022 	bch_err_fn(c, ret);
1023 	return bch2_err_class(ret);
1024 }
1025 
1026 static int bch2_open(struct inode *vinode, struct file *file)
1027 {
1028 	if (file->f_flags & (O_WRONLY|O_RDWR)) {
1029 		struct bch_inode_info *inode = to_bch_ei(vinode);
1030 		struct bch_fs *c = inode->v.i_sb->s_fs_info;
1031 
1032 		int ret = bch2_subvol_is_ro(c, inode->ei_subvol);
1033 		if (ret)
1034 			return ret;
1035 	}
1036 
1037 	return generic_file_open(vinode, file);
1038 }
1039 
1040 static const struct file_operations bch_file_operations = {
1041 	.open		= bch2_open,
1042 	.llseek		= bch2_llseek,
1043 	.read_iter	= bch2_read_iter,
1044 	.write_iter	= bch2_write_iter,
1045 	.mmap		= bch2_mmap,
1046 	.fsync		= bch2_fsync,
1047 	.splice_read	= filemap_splice_read,
1048 	.splice_write	= iter_file_splice_write,
1049 	.fallocate	= bch2_fallocate_dispatch,
1050 	.unlocked_ioctl = bch2_fs_file_ioctl,
1051 #ifdef CONFIG_COMPAT
1052 	.compat_ioctl	= bch2_compat_fs_ioctl,
1053 #endif
1054 	.remap_file_range = bch2_remap_file_range,
1055 };
1056 
1057 static const struct inode_operations bch_file_inode_operations = {
1058 	.getattr	= bch2_getattr,
1059 	.setattr	= bch2_setattr,
1060 	.fiemap		= bch2_fiemap,
1061 	.listxattr	= bch2_xattr_list,
1062 #ifdef CONFIG_BCACHEFS_POSIX_ACL
1063 	.get_acl	= bch2_get_acl,
1064 	.set_acl	= bch2_set_acl,
1065 #endif
1066 };
1067 
1068 static const struct inode_operations bch_dir_inode_operations = {
1069 	.lookup		= bch2_lookup,
1070 	.create		= bch2_create,
1071 	.link		= bch2_link,
1072 	.unlink		= bch2_unlink,
1073 	.symlink	= bch2_symlink,
1074 	.mkdir		= bch2_mkdir,
1075 	.rmdir		= bch2_unlink,
1076 	.mknod		= bch2_mknod,
1077 	.rename		= bch2_rename2,
1078 	.getattr	= bch2_getattr,
1079 	.setattr	= bch2_setattr,
1080 	.tmpfile	= bch2_tmpfile,
1081 	.listxattr	= bch2_xattr_list,
1082 #ifdef CONFIG_BCACHEFS_POSIX_ACL
1083 	.get_acl	= bch2_get_acl,
1084 	.set_acl	= bch2_set_acl,
1085 #endif
1086 };
1087 
1088 static const struct file_operations bch_dir_file_operations = {
1089 	.llseek		= bch2_dir_llseek,
1090 	.read		= generic_read_dir,
1091 	.iterate_shared	= bch2_vfs_readdir,
1092 	.fsync		= bch2_fsync,
1093 	.unlocked_ioctl = bch2_fs_file_ioctl,
1094 #ifdef CONFIG_COMPAT
1095 	.compat_ioctl	= bch2_compat_fs_ioctl,
1096 #endif
1097 };
1098 
1099 static const struct inode_operations bch_symlink_inode_operations = {
1100 	.get_link	= page_get_link,
1101 	.getattr	= bch2_getattr,
1102 	.setattr	= bch2_setattr,
1103 	.listxattr	= bch2_xattr_list,
1104 #ifdef CONFIG_BCACHEFS_POSIX_ACL
1105 	.get_acl	= bch2_get_acl,
1106 	.set_acl	= bch2_set_acl,
1107 #endif
1108 };
1109 
1110 static const struct inode_operations bch_special_inode_operations = {
1111 	.getattr	= bch2_getattr,
1112 	.setattr	= bch2_setattr,
1113 	.listxattr	= bch2_xattr_list,
1114 #ifdef CONFIG_BCACHEFS_POSIX_ACL
1115 	.get_acl	= bch2_get_acl,
1116 	.set_acl	= bch2_set_acl,
1117 #endif
1118 };
1119 
1120 static const struct address_space_operations bch_address_space_operations = {
1121 	.read_folio	= bch2_read_folio,
1122 	.writepages	= bch2_writepages,
1123 	.readahead	= bch2_readahead,
1124 	.dirty_folio	= filemap_dirty_folio,
1125 	.write_begin	= bch2_write_begin,
1126 	.write_end	= bch2_write_end,
1127 	.invalidate_folio = bch2_invalidate_folio,
1128 	.release_folio	= bch2_release_folio,
1129 	.direct_IO	= noop_direct_IO,
1130 #ifdef CONFIG_MIGRATION
1131 	.migrate_folio	= filemap_migrate_folio,
1132 #endif
1133 	.error_remove_folio = generic_error_remove_folio,
1134 };
1135 
1136 struct bcachefs_fid {
1137 	u64		inum;
1138 	u32		subvol;
1139 	u32		gen;
1140 } __packed;
1141 
1142 struct bcachefs_fid_with_parent {
1143 	struct bcachefs_fid	fid;
1144 	struct bcachefs_fid	dir;
1145 } __packed;
1146 
1147 static int bcachefs_fid_valid(int fh_len, int fh_type)
1148 {
1149 	switch (fh_type) {
1150 	case FILEID_BCACHEFS_WITHOUT_PARENT:
1151 		return fh_len == sizeof(struct bcachefs_fid) / sizeof(u32);
1152 	case FILEID_BCACHEFS_WITH_PARENT:
1153 		return fh_len == sizeof(struct bcachefs_fid_with_parent) / sizeof(u32);
1154 	default:
1155 		return false;
1156 	}
1157 }
1158 
1159 static struct bcachefs_fid bch2_inode_to_fid(struct bch_inode_info *inode)
1160 {
1161 	return (struct bcachefs_fid) {
1162 		.inum	= inode->ei_inode.bi_inum,
1163 		.subvol	= inode->ei_subvol,
1164 		.gen	= inode->ei_inode.bi_generation,
1165 	};
1166 }
1167 
1168 static int bch2_encode_fh(struct inode *vinode, u32 *fh, int *len,
1169 			  struct inode *vdir)
1170 {
1171 	struct bch_inode_info *inode	= to_bch_ei(vinode);
1172 	struct bch_inode_info *dir	= to_bch_ei(vdir);
1173 	int min_len;
1174 
1175 	if (!S_ISDIR(inode->v.i_mode) && dir) {
1176 		struct bcachefs_fid_with_parent *fid = (void *) fh;
1177 
1178 		min_len = sizeof(*fid) / sizeof(u32);
1179 		if (*len < min_len) {
1180 			*len = min_len;
1181 			return FILEID_INVALID;
1182 		}
1183 
1184 		fid->fid = bch2_inode_to_fid(inode);
1185 		fid->dir = bch2_inode_to_fid(dir);
1186 
1187 		*len = min_len;
1188 		return FILEID_BCACHEFS_WITH_PARENT;
1189 	} else {
1190 		struct bcachefs_fid *fid = (void *) fh;
1191 
1192 		min_len = sizeof(*fid) / sizeof(u32);
1193 		if (*len < min_len) {
1194 			*len = min_len;
1195 			return FILEID_INVALID;
1196 		}
1197 		*fid = bch2_inode_to_fid(inode);
1198 
1199 		*len = min_len;
1200 		return FILEID_BCACHEFS_WITHOUT_PARENT;
1201 	}
1202 }
1203 
1204 static struct inode *bch2_nfs_get_inode(struct super_block *sb,
1205 					struct bcachefs_fid fid)
1206 {
1207 	struct bch_fs *c = sb->s_fs_info;
1208 	struct inode *vinode = bch2_vfs_inode_get(c, (subvol_inum) {
1209 				    .subvol = fid.subvol,
1210 				    .inum = fid.inum,
1211 	});
1212 	if (!IS_ERR(vinode) && vinode->i_generation != fid.gen) {
1213 		iput(vinode);
1214 		vinode = ERR_PTR(-ESTALE);
1215 	}
1216 	return vinode;
1217 }
1218 
1219 static struct dentry *bch2_fh_to_dentry(struct super_block *sb, struct fid *_fid,
1220 		int fh_len, int fh_type)
1221 {
1222 	struct bcachefs_fid *fid = (void *) _fid;
1223 
1224 	if (!bcachefs_fid_valid(fh_len, fh_type))
1225 		return NULL;
1226 
1227 	return d_obtain_alias(bch2_nfs_get_inode(sb, *fid));
1228 }
1229 
1230 static struct dentry *bch2_fh_to_parent(struct super_block *sb, struct fid *_fid,
1231 		int fh_len, int fh_type)
1232 {
1233 	struct bcachefs_fid_with_parent *fid = (void *) _fid;
1234 
1235 	if (!bcachefs_fid_valid(fh_len, fh_type) ||
1236 	    fh_type != FILEID_BCACHEFS_WITH_PARENT)
1237 		return NULL;
1238 
1239 	return d_obtain_alias(bch2_nfs_get_inode(sb, fid->dir));
1240 }
1241 
1242 static struct dentry *bch2_get_parent(struct dentry *child)
1243 {
1244 	struct bch_inode_info *inode = to_bch_ei(child->d_inode);
1245 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
1246 	subvol_inum parent_inum = {
1247 		.subvol = inode->ei_inode.bi_parent_subvol ?:
1248 			inode->ei_subvol,
1249 		.inum = inode->ei_inode.bi_dir,
1250 	};
1251 
1252 	return d_obtain_alias(bch2_vfs_inode_get(c, parent_inum));
1253 }
1254 
1255 static int bch2_get_name(struct dentry *parent, char *name, struct dentry *child)
1256 {
1257 	struct bch_inode_info *inode	= to_bch_ei(child->d_inode);
1258 	struct bch_inode_info *dir	= to_bch_ei(parent->d_inode);
1259 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
1260 	struct btree_trans *trans;
1261 	struct btree_iter iter1;
1262 	struct btree_iter iter2;
1263 	struct bkey_s_c k;
1264 	struct bkey_s_c_dirent d;
1265 	struct bch_inode_unpacked inode_u;
1266 	subvol_inum target;
1267 	u32 snapshot;
1268 	struct qstr dirent_name;
1269 	unsigned name_len = 0;
1270 	int ret;
1271 
1272 	if (!S_ISDIR(dir->v.i_mode))
1273 		return -EINVAL;
1274 
1275 	trans = bch2_trans_get(c);
1276 
1277 	bch2_trans_iter_init(trans, &iter1, BTREE_ID_dirents,
1278 			     POS(dir->ei_inode.bi_inum, 0), 0);
1279 	bch2_trans_iter_init(trans, &iter2, BTREE_ID_dirents,
1280 			     POS(dir->ei_inode.bi_inum, 0), 0);
1281 retry:
1282 	bch2_trans_begin(trans);
1283 
1284 	ret = bch2_subvolume_get_snapshot(trans, dir->ei_subvol, &snapshot);
1285 	if (ret)
1286 		goto err;
1287 
1288 	bch2_btree_iter_set_snapshot(&iter1, snapshot);
1289 	bch2_btree_iter_set_snapshot(&iter2, snapshot);
1290 
1291 	ret = bch2_inode_find_by_inum_trans(trans, inode_inum(inode), &inode_u);
1292 	if (ret)
1293 		goto err;
1294 
1295 	if (inode_u.bi_dir == dir->ei_inode.bi_inum) {
1296 		bch2_btree_iter_set_pos(&iter1, POS(inode_u.bi_dir, inode_u.bi_dir_offset));
1297 
1298 		k = bch2_btree_iter_peek_slot(&iter1);
1299 		ret = bkey_err(k);
1300 		if (ret)
1301 			goto err;
1302 
1303 		if (k.k->type != KEY_TYPE_dirent) {
1304 			ret = -BCH_ERR_ENOENT_dirent_doesnt_match_inode;
1305 			goto err;
1306 		}
1307 
1308 		d = bkey_s_c_to_dirent(k);
1309 		ret = bch2_dirent_read_target(trans, inode_inum(dir), d, &target);
1310 		if (ret > 0)
1311 			ret = -BCH_ERR_ENOENT_dirent_doesnt_match_inode;
1312 		if (ret)
1313 			goto err;
1314 
1315 		if (target.subvol	== inode->ei_subvol &&
1316 		    target.inum		== inode->ei_inode.bi_inum)
1317 			goto found;
1318 	} else {
1319 		/*
1320 		 * File with multiple hardlinks and our backref is to the wrong
1321 		 * directory - linear search:
1322 		 */
1323 		for_each_btree_key_continue_norestart(iter2, 0, k, ret) {
1324 			if (k.k->p.inode > dir->ei_inode.bi_inum)
1325 				break;
1326 
1327 			if (k.k->type != KEY_TYPE_dirent)
1328 				continue;
1329 
1330 			d = bkey_s_c_to_dirent(k);
1331 			ret = bch2_dirent_read_target(trans, inode_inum(dir), d, &target);
1332 			if (ret < 0)
1333 				break;
1334 			if (ret)
1335 				continue;
1336 
1337 			if (target.subvol	== inode->ei_subvol &&
1338 			    target.inum		== inode->ei_inode.bi_inum)
1339 				goto found;
1340 		}
1341 	}
1342 
1343 	ret = -ENOENT;
1344 	goto err;
1345 found:
1346 	dirent_name = bch2_dirent_get_name(d);
1347 
1348 	name_len = min_t(unsigned, dirent_name.len, NAME_MAX);
1349 	memcpy(name, dirent_name.name, name_len);
1350 	name[name_len] = '\0';
1351 err:
1352 	if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
1353 		goto retry;
1354 
1355 	bch2_trans_iter_exit(trans, &iter1);
1356 	bch2_trans_iter_exit(trans, &iter2);
1357 	bch2_trans_put(trans);
1358 
1359 	return ret;
1360 }
1361 
1362 static const struct export_operations bch_export_ops = {
1363 	.encode_fh	= bch2_encode_fh,
1364 	.fh_to_dentry	= bch2_fh_to_dentry,
1365 	.fh_to_parent	= bch2_fh_to_parent,
1366 	.get_parent	= bch2_get_parent,
1367 	.get_name	= bch2_get_name,
1368 };
1369 
1370 static void bch2_vfs_inode_init(struct btree_trans *trans, subvol_inum inum,
1371 				struct bch_inode_info *inode,
1372 				struct bch_inode_unpacked *bi,
1373 				struct bch_subvolume *subvol)
1374 {
1375 	bch2_inode_update_after_write(trans, inode, bi, ~0);
1376 
1377 	if (BCH_SUBVOLUME_SNAP(subvol))
1378 		set_bit(EI_INODE_SNAPSHOT, &inode->ei_flags);
1379 	else
1380 		clear_bit(EI_INODE_SNAPSHOT, &inode->ei_flags);
1381 
1382 	inode->v.i_blocks	= bi->bi_sectors;
1383 	inode->v.i_ino		= bi->bi_inum;
1384 	inode->v.i_rdev		= bi->bi_dev;
1385 	inode->v.i_generation	= bi->bi_generation;
1386 	inode->v.i_size		= bi->bi_size;
1387 
1388 	inode->ei_flags		= 0;
1389 	inode->ei_quota_reserved = 0;
1390 	inode->ei_qid		= bch_qid(bi);
1391 	inode->ei_subvol	= inum.subvol;
1392 
1393 	inode->v.i_mapping->a_ops = &bch_address_space_operations;
1394 
1395 	switch (inode->v.i_mode & S_IFMT) {
1396 	case S_IFREG:
1397 		inode->v.i_op	= &bch_file_inode_operations;
1398 		inode->v.i_fop	= &bch_file_operations;
1399 		break;
1400 	case S_IFDIR:
1401 		inode->v.i_op	= &bch_dir_inode_operations;
1402 		inode->v.i_fop	= &bch_dir_file_operations;
1403 		break;
1404 	case S_IFLNK:
1405 		inode_nohighmem(&inode->v);
1406 		inode->v.i_op	= &bch_symlink_inode_operations;
1407 		break;
1408 	default:
1409 		init_special_inode(&inode->v, inode->v.i_mode, inode->v.i_rdev);
1410 		inode->v.i_op	= &bch_special_inode_operations;
1411 		break;
1412 	}
1413 
1414 	mapping_set_large_folios(inode->v.i_mapping);
1415 }
1416 
1417 static struct inode *bch2_alloc_inode(struct super_block *sb)
1418 {
1419 	struct bch_inode_info *inode;
1420 
1421 	inode = kmem_cache_alloc(bch2_inode_cache, GFP_NOFS);
1422 	if (!inode)
1423 		return NULL;
1424 
1425 	inode_init_once(&inode->v);
1426 	mutex_init(&inode->ei_update_lock);
1427 	two_state_lock_init(&inode->ei_pagecache_lock);
1428 	INIT_LIST_HEAD(&inode->ei_vfs_inode_list);
1429 	mutex_init(&inode->ei_quota_lock);
1430 
1431 	return &inode->v;
1432 }
1433 
1434 static void bch2_i_callback(struct rcu_head *head)
1435 {
1436 	struct inode *vinode = container_of(head, struct inode, i_rcu);
1437 	struct bch_inode_info *inode = to_bch_ei(vinode);
1438 
1439 	kmem_cache_free(bch2_inode_cache, inode);
1440 }
1441 
1442 static void bch2_destroy_inode(struct inode *vinode)
1443 {
1444 	call_rcu(&vinode->i_rcu, bch2_i_callback);
1445 }
1446 
1447 static int inode_update_times_fn(struct btree_trans *trans,
1448 				 struct bch_inode_info *inode,
1449 				 struct bch_inode_unpacked *bi,
1450 				 void *p)
1451 {
1452 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
1453 
1454 	bi->bi_atime	= timespec_to_bch2_time(c, inode_get_atime(&inode->v));
1455 	bi->bi_mtime	= timespec_to_bch2_time(c, inode_get_mtime(&inode->v));
1456 	bi->bi_ctime	= timespec_to_bch2_time(c, inode_get_ctime(&inode->v));
1457 
1458 	return 0;
1459 }
1460 
1461 static int bch2_vfs_write_inode(struct inode *vinode,
1462 				struct writeback_control *wbc)
1463 {
1464 	struct bch_fs *c = vinode->i_sb->s_fs_info;
1465 	struct bch_inode_info *inode = to_bch_ei(vinode);
1466 	int ret;
1467 
1468 	mutex_lock(&inode->ei_update_lock);
1469 	ret = bch2_write_inode(c, inode, inode_update_times_fn, NULL,
1470 			       ATTR_ATIME|ATTR_MTIME|ATTR_CTIME);
1471 	mutex_unlock(&inode->ei_update_lock);
1472 
1473 	return bch2_err_class(ret);
1474 }
1475 
1476 static void bch2_evict_inode(struct inode *vinode)
1477 {
1478 	struct bch_fs *c = vinode->i_sb->s_fs_info;
1479 	struct bch_inode_info *inode = to_bch_ei(vinode);
1480 
1481 	truncate_inode_pages_final(&inode->v.i_data);
1482 
1483 	clear_inode(&inode->v);
1484 
1485 	BUG_ON(!is_bad_inode(&inode->v) && inode->ei_quota_reserved);
1486 
1487 	if (!inode->v.i_nlink && !is_bad_inode(&inode->v)) {
1488 		bch2_quota_acct(c, inode->ei_qid, Q_SPC, -((s64) inode->v.i_blocks),
1489 				KEY_TYPE_QUOTA_WARN);
1490 		bch2_quota_acct(c, inode->ei_qid, Q_INO, -1,
1491 				KEY_TYPE_QUOTA_WARN);
1492 		bch2_inode_rm(c, inode_inum(inode));
1493 	}
1494 
1495 	mutex_lock(&c->vfs_inodes_lock);
1496 	list_del_init(&inode->ei_vfs_inode_list);
1497 	mutex_unlock(&c->vfs_inodes_lock);
1498 }
1499 
1500 void bch2_evict_subvolume_inodes(struct bch_fs *c, snapshot_id_list *s)
1501 {
1502 	struct bch_inode_info *inode;
1503 	DARRAY(struct bch_inode_info *) grabbed;
1504 	bool clean_pass = false, this_pass_clean;
1505 
1506 	/*
1507 	 * Initially, we scan for inodes without I_DONTCACHE, then mark them to
1508 	 * be pruned with d_mark_dontcache().
1509 	 *
1510 	 * Once we've had a clean pass where we didn't find any inodes without
1511 	 * I_DONTCACHE, we wait for them to be freed:
1512 	 */
1513 
1514 	darray_init(&grabbed);
1515 	darray_make_room(&grabbed, 1024);
1516 again:
1517 	cond_resched();
1518 	this_pass_clean = true;
1519 
1520 	mutex_lock(&c->vfs_inodes_lock);
1521 	list_for_each_entry(inode, &c->vfs_inodes_list, ei_vfs_inode_list) {
1522 		if (!snapshot_list_has_id(s, inode->ei_subvol))
1523 			continue;
1524 
1525 		if (!(inode->v.i_state & I_DONTCACHE) &&
1526 		    !(inode->v.i_state & I_FREEING) &&
1527 		    igrab(&inode->v)) {
1528 			this_pass_clean = false;
1529 
1530 			if (darray_push_gfp(&grabbed, inode, GFP_ATOMIC|__GFP_NOWARN)) {
1531 				iput(&inode->v);
1532 				break;
1533 			}
1534 		} else if (clean_pass && this_pass_clean) {
1535 			wait_queue_head_t *wq = bit_waitqueue(&inode->v.i_state, __I_NEW);
1536 			DEFINE_WAIT_BIT(wait, &inode->v.i_state, __I_NEW);
1537 
1538 			prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
1539 			mutex_unlock(&c->vfs_inodes_lock);
1540 
1541 			schedule();
1542 			finish_wait(wq, &wait.wq_entry);
1543 			goto again;
1544 		}
1545 	}
1546 	mutex_unlock(&c->vfs_inodes_lock);
1547 
1548 	darray_for_each(grabbed, i) {
1549 		inode = *i;
1550 		d_mark_dontcache(&inode->v);
1551 		d_prune_aliases(&inode->v);
1552 		iput(&inode->v);
1553 	}
1554 	grabbed.nr = 0;
1555 
1556 	if (!clean_pass || !this_pass_clean) {
1557 		clean_pass = this_pass_clean;
1558 		goto again;
1559 	}
1560 
1561 	darray_exit(&grabbed);
1562 }
1563 
1564 static int bch2_statfs(struct dentry *dentry, struct kstatfs *buf)
1565 {
1566 	struct super_block *sb = dentry->d_sb;
1567 	struct bch_fs *c = sb->s_fs_info;
1568 	struct bch_fs_usage_short usage = bch2_fs_usage_read_short(c);
1569 	unsigned shift = sb->s_blocksize_bits - 9;
1570 	/*
1571 	 * this assumes inodes take up 64 bytes, which is a decent average
1572 	 * number:
1573 	 */
1574 	u64 avail_inodes = ((usage.capacity - usage.used) << 3);
1575 	u64 fsid;
1576 
1577 	buf->f_type	= BCACHEFS_STATFS_MAGIC;
1578 	buf->f_bsize	= sb->s_blocksize;
1579 	buf->f_blocks	= usage.capacity >> shift;
1580 	buf->f_bfree	= usage.free >> shift;
1581 	buf->f_bavail	= avail_factor(usage.free) >> shift;
1582 
1583 	buf->f_files	= usage.nr_inodes + avail_inodes;
1584 	buf->f_ffree	= avail_inodes;
1585 
1586 	fsid = le64_to_cpup((void *) c->sb.user_uuid.b) ^
1587 	       le64_to_cpup((void *) c->sb.user_uuid.b + sizeof(u64));
1588 	buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
1589 	buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
1590 	buf->f_namelen	= BCH_NAME_MAX;
1591 
1592 	return 0;
1593 }
1594 
1595 static int bch2_sync_fs(struct super_block *sb, int wait)
1596 {
1597 	struct bch_fs *c = sb->s_fs_info;
1598 	int ret;
1599 
1600 	if (c->opts.journal_flush_disabled)
1601 		return 0;
1602 
1603 	if (!wait) {
1604 		bch2_journal_flush_async(&c->journal, NULL);
1605 		return 0;
1606 	}
1607 
1608 	ret = bch2_journal_flush(&c->journal);
1609 	return bch2_err_class(ret);
1610 }
1611 
1612 static struct bch_fs *bch2_path_to_fs(const char *path)
1613 {
1614 	struct bch_fs *c;
1615 	dev_t dev;
1616 	int ret;
1617 
1618 	ret = lookup_bdev(path, &dev);
1619 	if (ret)
1620 		return ERR_PTR(ret);
1621 
1622 	c = bch2_dev_to_fs(dev);
1623 	if (c)
1624 		closure_put(&c->cl);
1625 	return c ?: ERR_PTR(-ENOENT);
1626 }
1627 
1628 static int bch2_remount(struct super_block *sb, int *flags, char *data)
1629 {
1630 	struct bch_fs *c = sb->s_fs_info;
1631 	struct bch_opts opts = bch2_opts_empty();
1632 	int ret;
1633 
1634 	ret = bch2_parse_mount_opts(c, &opts, data);
1635 	if (ret)
1636 		goto err;
1637 
1638 	opt_set(opts, read_only, (*flags & SB_RDONLY) != 0);
1639 
1640 	if (opts.read_only != c->opts.read_only) {
1641 		down_write(&c->state_lock);
1642 
1643 		if (opts.read_only) {
1644 			bch2_fs_read_only(c);
1645 
1646 			sb->s_flags |= SB_RDONLY;
1647 		} else {
1648 			ret = bch2_fs_read_write(c);
1649 			if (ret) {
1650 				bch_err(c, "error going rw: %i", ret);
1651 				up_write(&c->state_lock);
1652 				ret = -EINVAL;
1653 				goto err;
1654 			}
1655 
1656 			sb->s_flags &= ~SB_RDONLY;
1657 		}
1658 
1659 		c->opts.read_only = opts.read_only;
1660 
1661 		up_write(&c->state_lock);
1662 	}
1663 
1664 	if (opt_defined(opts, errors))
1665 		c->opts.errors = opts.errors;
1666 err:
1667 	return bch2_err_class(ret);
1668 }
1669 
1670 static int bch2_show_devname(struct seq_file *seq, struct dentry *root)
1671 {
1672 	struct bch_fs *c = root->d_sb->s_fs_info;
1673 	bool first = true;
1674 
1675 	for_each_online_member(c, ca) {
1676 		if (!first)
1677 			seq_putc(seq, ':');
1678 		first = false;
1679 		seq_puts(seq, ca->disk_sb.sb_name);
1680 	}
1681 
1682 	return 0;
1683 }
1684 
1685 static int bch2_show_options(struct seq_file *seq, struct dentry *root)
1686 {
1687 	struct bch_fs *c = root->d_sb->s_fs_info;
1688 	enum bch_opt_id i;
1689 	struct printbuf buf = PRINTBUF;
1690 	int ret = 0;
1691 
1692 	for (i = 0; i < bch2_opts_nr; i++) {
1693 		const struct bch_option *opt = &bch2_opt_table[i];
1694 		u64 v = bch2_opt_get_by_id(&c->opts, i);
1695 
1696 		if (!(opt->flags & OPT_MOUNT))
1697 			continue;
1698 
1699 		if (v == bch2_opt_get_by_id(&bch2_opts_default, i))
1700 			continue;
1701 
1702 		printbuf_reset(&buf);
1703 		bch2_opt_to_text(&buf, c, c->disk_sb.sb, opt, v,
1704 				 OPT_SHOW_MOUNT_STYLE);
1705 		seq_putc(seq, ',');
1706 		seq_puts(seq, buf.buf);
1707 	}
1708 
1709 	if (buf.allocation_failure)
1710 		ret = -ENOMEM;
1711 	printbuf_exit(&buf);
1712 	return ret;
1713 }
1714 
1715 static void bch2_put_super(struct super_block *sb)
1716 {
1717 	struct bch_fs *c = sb->s_fs_info;
1718 
1719 	__bch2_fs_stop(c);
1720 }
1721 
1722 /*
1723  * bcachefs doesn't currently integrate intwrite freeze protection but the
1724  * internal write references serve the same purpose. Therefore reuse the
1725  * read-only transition code to perform the quiesce. The caveat is that we don't
1726  * currently have the ability to block tasks that want a write reference while
1727  * the superblock is frozen. This is fine for now, but we should either add
1728  * blocking support or find a way to integrate sb_start_intwrite() and friends.
1729  */
1730 static int bch2_freeze(struct super_block *sb)
1731 {
1732 	struct bch_fs *c = sb->s_fs_info;
1733 
1734 	down_write(&c->state_lock);
1735 	bch2_fs_read_only(c);
1736 	up_write(&c->state_lock);
1737 	return 0;
1738 }
1739 
1740 static int bch2_unfreeze(struct super_block *sb)
1741 {
1742 	struct bch_fs *c = sb->s_fs_info;
1743 	int ret;
1744 
1745 	if (test_bit(BCH_FS_emergency_ro, &c->flags))
1746 		return 0;
1747 
1748 	down_write(&c->state_lock);
1749 	ret = bch2_fs_read_write(c);
1750 	up_write(&c->state_lock);
1751 	return ret;
1752 }
1753 
1754 static const struct super_operations bch_super_operations = {
1755 	.alloc_inode	= bch2_alloc_inode,
1756 	.destroy_inode	= bch2_destroy_inode,
1757 	.write_inode	= bch2_vfs_write_inode,
1758 	.evict_inode	= bch2_evict_inode,
1759 	.sync_fs	= bch2_sync_fs,
1760 	.statfs		= bch2_statfs,
1761 	.show_devname	= bch2_show_devname,
1762 	.show_options	= bch2_show_options,
1763 	.remount_fs	= bch2_remount,
1764 	.put_super	= bch2_put_super,
1765 	.freeze_fs	= bch2_freeze,
1766 	.unfreeze_fs	= bch2_unfreeze,
1767 };
1768 
1769 static int bch2_set_super(struct super_block *s, void *data)
1770 {
1771 	s->s_fs_info = data;
1772 	return 0;
1773 }
1774 
1775 static int bch2_noset_super(struct super_block *s, void *data)
1776 {
1777 	return -EBUSY;
1778 }
1779 
1780 typedef DARRAY(struct bch_fs *) darray_fs;
1781 
1782 static int bch2_test_super(struct super_block *s, void *data)
1783 {
1784 	struct bch_fs *c = s->s_fs_info;
1785 	darray_fs *d = data;
1786 
1787 	if (!c)
1788 		return false;
1789 
1790 	darray_for_each(*d, i)
1791 		if (c != *i)
1792 			return false;
1793 	return true;
1794 }
1795 
1796 static struct dentry *bch2_mount(struct file_system_type *fs_type,
1797 				 int flags, const char *dev_name, void *data)
1798 {
1799 	struct bch_fs *c;
1800 	struct super_block *sb;
1801 	struct inode *vinode;
1802 	struct bch_opts opts = bch2_opts_empty();
1803 	int ret;
1804 
1805 	opt_set(opts, read_only, (flags & SB_RDONLY) != 0);
1806 
1807 	ret = bch2_parse_mount_opts(NULL, &opts, data);
1808 	if (ret)
1809 		return ERR_PTR(ret);
1810 
1811 	if (!dev_name || strlen(dev_name) == 0)
1812 		return ERR_PTR(-EINVAL);
1813 
1814 	darray_str devs;
1815 	ret = bch2_split_devs(dev_name, &devs);
1816 	if (ret)
1817 		return ERR_PTR(ret);
1818 
1819 	darray_fs devs_to_fs = {};
1820 	darray_for_each(devs, i) {
1821 		ret = darray_push(&devs_to_fs, bch2_path_to_fs(*i));
1822 		if (ret) {
1823 			sb = ERR_PTR(ret);
1824 			goto got_sb;
1825 		}
1826 	}
1827 
1828 	sb = sget(fs_type, bch2_test_super, bch2_noset_super, flags|SB_NOSEC, &devs_to_fs);
1829 	if (!IS_ERR(sb))
1830 		goto got_sb;
1831 
1832 	c = bch2_fs_open(devs.data, devs.nr, opts);
1833 	if (IS_ERR(c)) {
1834 		sb = ERR_CAST(c);
1835 		goto got_sb;
1836 	}
1837 
1838 	/* Some options can't be parsed until after the fs is started: */
1839 	ret = bch2_parse_mount_opts(c, &opts, data);
1840 	if (ret) {
1841 		bch2_fs_stop(c);
1842 		sb = ERR_PTR(ret);
1843 		goto got_sb;
1844 	}
1845 
1846 	bch2_opts_apply(&c->opts, opts);
1847 
1848 	sb = sget(fs_type, NULL, bch2_set_super, flags|SB_NOSEC, c);
1849 	if (IS_ERR(sb))
1850 		bch2_fs_stop(c);
1851 got_sb:
1852 	darray_exit(&devs_to_fs);
1853 	bch2_darray_str_exit(&devs);
1854 
1855 	if (IS_ERR(sb)) {
1856 		ret = PTR_ERR(sb);
1857 		ret = bch2_err_class(ret);
1858 		return ERR_PTR(ret);
1859 	}
1860 
1861 	c = sb->s_fs_info;
1862 
1863 	if (sb->s_root) {
1864 		if ((flags ^ sb->s_flags) & SB_RDONLY) {
1865 			ret = -EBUSY;
1866 			goto err_put_super;
1867 		}
1868 		goto out;
1869 	}
1870 
1871 	sb->s_blocksize		= block_bytes(c);
1872 	sb->s_blocksize_bits	= ilog2(block_bytes(c));
1873 	sb->s_maxbytes		= MAX_LFS_FILESIZE;
1874 	sb->s_op		= &bch_super_operations;
1875 	sb->s_export_op		= &bch_export_ops;
1876 #ifdef CONFIG_BCACHEFS_QUOTA
1877 	sb->s_qcop		= &bch2_quotactl_operations;
1878 	sb->s_quota_types	= QTYPE_MASK_USR|QTYPE_MASK_GRP|QTYPE_MASK_PRJ;
1879 #endif
1880 	sb->s_xattr		= bch2_xattr_handlers;
1881 	sb->s_magic		= BCACHEFS_STATFS_MAGIC;
1882 	sb->s_time_gran		= c->sb.nsec_per_time_unit;
1883 	sb->s_time_min		= div_s64(S64_MIN, c->sb.time_units_per_sec) + 1;
1884 	sb->s_time_max		= div_s64(S64_MAX, c->sb.time_units_per_sec);
1885 	c->vfs_sb		= sb;
1886 	strscpy(sb->s_id, c->name, sizeof(sb->s_id));
1887 
1888 	ret = super_setup_bdi(sb);
1889 	if (ret)
1890 		goto err_put_super;
1891 
1892 	sb->s_bdi->ra_pages		= VM_READAHEAD_PAGES;
1893 
1894 	for_each_online_member(c, ca) {
1895 		struct block_device *bdev = ca->disk_sb.bdev;
1896 
1897 		/* XXX: create an anonymous device for multi device filesystems */
1898 		sb->s_bdev	= bdev;
1899 		sb->s_dev	= bdev->bd_dev;
1900 		percpu_ref_put(&ca->io_ref);
1901 		break;
1902 	}
1903 
1904 	c->dev = sb->s_dev;
1905 
1906 #ifdef CONFIG_BCACHEFS_POSIX_ACL
1907 	if (c->opts.acl)
1908 		sb->s_flags	|= SB_POSIXACL;
1909 #endif
1910 
1911 	sb->s_shrink->seeks = 0;
1912 
1913 	vinode = bch2_vfs_inode_get(c, BCACHEFS_ROOT_SUBVOL_INUM);
1914 	ret = PTR_ERR_OR_ZERO(vinode);
1915 	bch_err_msg(c, ret, "mounting: error getting root inode");
1916 	if (ret)
1917 		goto err_put_super;
1918 
1919 	sb->s_root = d_make_root(vinode);
1920 	if (!sb->s_root) {
1921 		bch_err(c, "error mounting: error allocating root dentry");
1922 		ret = -ENOMEM;
1923 		goto err_put_super;
1924 	}
1925 
1926 	sb->s_flags |= SB_ACTIVE;
1927 out:
1928 	return dget(sb->s_root);
1929 
1930 err_put_super:
1931 	deactivate_locked_super(sb);
1932 	return ERR_PTR(bch2_err_class(ret));
1933 }
1934 
1935 static void bch2_kill_sb(struct super_block *sb)
1936 {
1937 	struct bch_fs *c = sb->s_fs_info;
1938 
1939 	generic_shutdown_super(sb);
1940 	bch2_fs_free(c);
1941 }
1942 
1943 static struct file_system_type bcache_fs_type = {
1944 	.owner		= THIS_MODULE,
1945 	.name		= "bcachefs",
1946 	.mount		= bch2_mount,
1947 	.kill_sb	= bch2_kill_sb,
1948 	.fs_flags	= FS_REQUIRES_DEV,
1949 };
1950 
1951 MODULE_ALIAS_FS("bcachefs");
1952 
1953 void bch2_vfs_exit(void)
1954 {
1955 	unregister_filesystem(&bcache_fs_type);
1956 	kmem_cache_destroy(bch2_inode_cache);
1957 }
1958 
1959 int __init bch2_vfs_init(void)
1960 {
1961 	int ret = -ENOMEM;
1962 
1963 	bch2_inode_cache = KMEM_CACHE(bch_inode_info, SLAB_RECLAIM_ACCOUNT);
1964 	if (!bch2_inode_cache)
1965 		goto err;
1966 
1967 	ret = register_filesystem(&bcache_fs_type);
1968 	if (ret)
1969 		goto err;
1970 
1971 	return 0;
1972 err:
1973 	bch2_vfs_exit();
1974 	return ret;
1975 }
1976 
1977 #endif /* NO_BCACHEFS_FS */
1978