1	// SPDX-License-Identifier: GPL-2.0
2	/*
3	* Copyright (C) 2007 Oracle. All rights reserved.
4	*/
5
6	#include <linux/fs.h>
7	#include <linux/blkdev.h>
8	#include <linux/radix-tree.h>
9	#include <linux/writeback.h>
10	#include <linux/workqueue.h>
11	#include <linux/kthread.h>
12	#include <linux/slab.h>
13	#include <linux/migrate.h>
14	#include <linux/ratelimit.h>
15	#include <linux/uuid.h>
16	#include <linux/semaphore.h>
17	#include <linux/error-injection.h>
18	#include <linux/crc32c.h>
19	#include <linux/sched/mm.h>
20	#include <linux/unaligned.h>
21	#include <crypto/hash.h>
22	#include "ctree.h"
23	#include "disk-io.h"
24	#include "transaction.h"
25	#include "btrfs_inode.h"
26	#include "bio.h"
27	#include "print-tree.h"
28	#include "locking.h"
29	#include "tree-log.h"
30	#include "free-space-cache.h"
31	#include "free-space-tree.h"
32	#include "dev-replace.h"
33	#include "raid56.h"
34	#include "sysfs.h"
35	#include "qgroup.h"
36	#include "compression.h"
37	#include "tree-checker.h"
38	#include "ref-verify.h"
39	#include "block-group.h"
40	#include "discard.h"
41	#include "space-info.h"
42	#include "zoned.h"
43	#include "subpage.h"
44	#include "fs.h"
45	#include "accessors.h"
46	#include "extent-tree.h"
47	#include "root-tree.h"
48	#include "defrag.h"
49	#include "uuid-tree.h"
50	#include "relocation.h"
51	#include "scrub.h"
52	#include "super.h"
53	#include "delayed-inode.h"
54
55	#define BTRFS_SUPER_FLAG_SUPP (BTRFS_HEADER_FLAG_WRITTEN |\
56	BTRFS_HEADER_FLAG_RELOC |\
57	BTRFS_SUPER_FLAG_ERROR |\
58	BTRFS_SUPER_FLAG_SEEDING |\
59	BTRFS_SUPER_FLAG_METADUMP |\
60	BTRFS_SUPER_FLAG_METADUMP_V2)
61
62	static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info);
63	static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info);
64
65	static void btrfs_free_csum_hash(struct btrfs_fs_info *fs_info)
66	{
67	if (fs_info->csum_shash)
68	crypto_free_shash(tfm: fs_info->csum_shash);
69	}
70
71	/*
72	* Compute the csum of a btree block and store the result to provided buffer.
73	*/
74	static void csum_tree_block(struct extent_buffer *buf, u8 *result)
75	{
76	struct btrfs_fs_info *fs_info = buf->fs_info;
77	int num_pages;
78	u32 first_page_part;
79	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
80	char *kaddr;
81	int i;
82
83	shash->tfm = fs_info->csum_shash;
84	crypto_shash_init(desc: shash);
85
86	if (buf->addr) {
87	/* Pages are contiguous, handle them as a big one. */
88	kaddr = buf->addr;
89	first_page_part = fs_info->nodesize;
90	num_pages = 1;
91	} else {
92	kaddr = folio_address(folio: buf->folios[0]);
93	first_page_part = min_t(u32, PAGE_SIZE, fs_info->nodesize);
94	num_pages = num_extent_pages(eb: buf);
95	}
96
97	crypto_shash_update(desc: shash, data: kaddr + BTRFS_CSUM_SIZE,
98	len: first_page_part - BTRFS_CSUM_SIZE);
99
100	/*
101	* Multiple single-page folios case would reach here.
102	*
103	* nodesize <= PAGE_SIZE and large folio all handled by above
104	* crypto_shash_update() already.
105	*/
106	for (i = 1; i < num_pages && INLINE_EXTENT_BUFFER_PAGES > 1; i++) {
107	kaddr = folio_address(folio: buf->folios[i]);
108	crypto_shash_update(desc: shash, data: kaddr, PAGE_SIZE);
109	}
110	memset(result, 0, BTRFS_CSUM_SIZE);
111	crypto_shash_final(desc: shash, out: result);
112	}
113
114	/*
115	* we can't consider a given block up to date unless the transid of the
116	* block matches the transid in the parent node's pointer. This is how we
117	* detect blocks that either didn't get written at all or got written
118	* in the wrong place.
119	*/
120	int btrfs_buffer_uptodate(struct extent_buffer *eb, u64 parent_transid, bool atomic)
121	{
122	if (!extent_buffer_uptodate(eb))
123	return 0;
124
125	if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
126	return 1;
127
128	if (atomic)
129	return -EAGAIN;
130
131	if (!extent_buffer_uptodate(eb) ||
132	btrfs_header_generation(eb) != parent_transid) {
133	btrfs_err_rl(eb->fs_info,
134	"parent transid verify failed on logical %llu mirror %u wanted %llu found %llu",
135	eb->start, eb->read_mirror,
136	parent_transid, btrfs_header_generation(eb));
137	clear_extent_buffer_uptodate(eb);
138	return 0;
139	}
140	return 1;
141	}
142
143	static bool btrfs_supported_super_csum(u16 csum_type)
144	{
145	switch (csum_type) {
146	case BTRFS_CSUM_TYPE_CRC32:
147	case BTRFS_CSUM_TYPE_XXHASH:
148	case BTRFS_CSUM_TYPE_SHA256:
149	case BTRFS_CSUM_TYPE_BLAKE2:
150	return true;
151	default:
152	return false;
153	}
154	}
155
156	/*
157	* Return 0 if the superblock checksum type matches the checksum value of that
158	* algorithm. Pass the raw disk superblock data.
159	*/
160	int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
161	const struct btrfs_super_block *disk_sb)
162	{
163	char result[BTRFS_CSUM_SIZE];
164	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
165
166	shash->tfm = fs_info->csum_shash;
167
168	/*
169	* The super_block structure does not span the whole
170	* BTRFS_SUPER_INFO_SIZE range, we expect that the unused space is
171	* filled with zeros and is included in the checksum.
172	*/
173	crypto_shash_digest(desc: shash, data: (const u8 *)disk_sb + BTRFS_CSUM_SIZE,
174	BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE, out: result);
175
176	if (memcmp(p: disk_sb->csum, q: result, size: fs_info->csum_size))
177	return 1;
178
179	return 0;
180	}
181
182	static int btrfs_repair_eb_io_failure(const struct extent_buffer *eb,
183	int mirror_num)
184	{
185	struct btrfs_fs_info *fs_info = eb->fs_info;
186	const u32 step = min(fs_info->nodesize, PAGE_SIZE);
187	const u32 nr_steps = eb->len / step;
188	phys_addr_t paddrs[BTRFS_MAX_BLOCKSIZE / PAGE_SIZE];
189	int ret = 0;
190
191	if (sb_rdonly(sb: fs_info->sb))
192	return -EROFS;
193
194	for (int i = 0; i < num_extent_pages(eb); i++) {
195	struct folio *folio = eb->folios[i];
196
197	/* No large folio support yet. */
198	ASSERT(folio_order(folio) == 0);
199	ASSERT(i < nr_steps);
200
201	/*
202	* For nodesize < page size, there is just one paddr, with some
203	* offset inside the page.
204	*
205	* For nodesize >= page size, it's one or more paddrs, and eb->start
206	* must be aligned to page boundary.
207	*/
208	paddrs[i] = page_to_phys(&folio->page) + offset_in_page(eb->start);
209	}
210
211	ret = btrfs_repair_io_failure(fs_info, ino: 0, fileoff: eb->start, length: eb->len, logical: eb->start,
212	paddrs, step, mirror_num);
213	return ret;
214	}
215
216	/*
217	* helper to read a given tree block, doing retries as required when
218	* the checksums don't match and we have alternate mirrors to try.
219	*
220	* @check: expected tree parentness check, see the comments of the
221	* structure for details.
222	*/
223	int btrfs_read_extent_buffer(struct extent_buffer *eb,
224	const struct btrfs_tree_parent_check *check)
225	{
226	struct btrfs_fs_info *fs_info = eb->fs_info;
227	int failed = 0;
228	int ret;
229	int num_copies = 0;
230	int mirror_num = 0;
231	int failed_mirror = 0;
232
233	ASSERT(check);
234
235	while (1) {
236	ret = read_extent_buffer_pages(eb, mirror_num, parent_check: check);
237	if (!ret)
238	break;
239
240	num_copies = btrfs_num_copies(fs_info,
241	logical: eb->start, len: eb->len);
242	if (num_copies == 1)
243	break;
244
245	if (!failed_mirror) {
246	failed = 1;
247	failed_mirror = eb->read_mirror;
248	}
249
250	mirror_num++;
251	if (mirror_num == failed_mirror)
252	mirror_num++;
253
254	if (mirror_num > num_copies)
255	break;
256	}
257
258	if (failed && !ret && failed_mirror)
259	btrfs_repair_eb_io_failure(eb, mirror_num: failed_mirror);
260
261	return ret;
262	}
263
264	/*
265	* Checksum a dirty tree block before IO.
266	*/
267	int btree_csum_one_bio(struct btrfs_bio *bbio)
268	{
269	struct extent_buffer *eb = bbio->private;
270	struct btrfs_fs_info *fs_info = eb->fs_info;
271	u64 found_start = btrfs_header_bytenr(eb);
272	u64 last_trans;
273	u8 result[BTRFS_CSUM_SIZE];
274	int ret;
275
276	/* Btree blocks are always contiguous on disk. */
277	if (WARN_ON_ONCE(bbio->file_offset != eb->start))
278	return -EIO;
279	if (WARN_ON_ONCE(bbio->bio.bi_iter.bi_size != eb->len))
280	return -EIO;
281
282	/*
283	* If an extent_buffer is marked as EXTENT_BUFFER_ZONED_ZEROOUT, don't
284	* checksum it but zero-out its content. This is done to preserve
285	* ordering of I/O without unnecessarily writing out data.
286	*/
287	if (test_bit(EXTENT_BUFFER_ZONED_ZEROOUT, &eb->bflags)) {
288	memzero_extent_buffer(eb, start: 0, len: eb->len);
289	return 0;
290	}
291
292	if (WARN_ON_ONCE(found_start != eb->start))
293	return -EIO;
294	if (WARN_ON(!btrfs_meta_folio_test_uptodate(eb->folios[0], eb)))
295	return -EIO;
296
297	ASSERT(memcmp_extent_buffer(eb, fs_info->fs_devices->metadata_uuid,
298	offsetof(struct btrfs_header, fsid),
299	BTRFS_FSID_SIZE) == 0);
300	csum_tree_block(buf: eb, result);
301
302	if (btrfs_header_level(eb))
303	ret = btrfs_check_node(node: eb);
304	else
305	ret = btrfs_check_leaf(leaf: eb);
306
307	if (ret < 0)
308	goto error;
309
310	/*
311	* Also check the generation, the eb reached here must be newer than
312	* last committed. Or something seriously wrong happened.
313	*/
314	last_trans = btrfs_get_last_trans_committed(fs_info);
315	if (unlikely(btrfs_header_generation(eb) <= last_trans)) {
316	ret = -EUCLEAN;
317	btrfs_err(fs_info,
318	"block=%llu bad generation, have %llu expect > %llu",
319	eb->start, btrfs_header_generation(eb), last_trans);
320	goto error;
321	}
322	write_extent_buffer(eb, src: result, start: 0, len: fs_info->csum_size);
323	return 0;
324
325	error:
326	btrfs_print_tree(c: eb, follow: 0);
327	btrfs_err(fs_info, "block=%llu write time tree block corruption detected",
328	eb->start);
329	/*
330	* Be noisy if this is an extent buffer from a log tree. We don't abort
331	* a transaction in case there's a bad log tree extent buffer, we just
332	* fallback to a transaction commit. Still we want to know when there is
333	* a bad log tree extent buffer, as that may signal a bug somewhere.
334	*/
335	WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG) ||
336	btrfs_header_owner(eb) == BTRFS_TREE_LOG_OBJECTID);
337	return ret;
338	}
339
340	static bool check_tree_block_fsid(struct extent_buffer *eb)
341	{
342	struct btrfs_fs_info *fs_info = eb->fs_info;
343	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
344	u8 fsid[BTRFS_FSID_SIZE];
345
346	read_extent_buffer(eb, dst: fsid, offsetof(struct btrfs_header, fsid),
347	BTRFS_FSID_SIZE);
348
349	/*
350	* alloc_fsid_devices() copies the fsid into fs_devices::metadata_uuid.
351	* This is then overwritten by metadata_uuid if it is present in the
352	* device_list_add(). The same true for a seed device as well. So use of
353	* fs_devices::metadata_uuid is appropriate here.
354	*/
355	if (memcmp(p: fsid, q: fs_info->fs_devices->metadata_uuid, BTRFS_FSID_SIZE) == 0)
356	return false;
357
358	list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list)
359	if (!memcmp(p: fsid, q: seed_devs->fsid, BTRFS_FSID_SIZE))
360	return false;
361
362	return true;
363	}
364
365	/* Do basic extent buffer checks at read time */
366	int btrfs_validate_extent_buffer(struct extent_buffer *eb,
367	const struct btrfs_tree_parent_check *check)
368	{
369	struct btrfs_fs_info *fs_info = eb->fs_info;
370	u64 found_start;
371	const u32 csum_size = fs_info->csum_size;
372	u8 found_level;
373	u8 result[BTRFS_CSUM_SIZE];
374	const u8 *header_csum;
375	int ret = 0;
376	const bool ignore_csum = btrfs_test_opt(fs_info, IGNOREMETACSUMS);
377
378	ASSERT(check);
379
380	found_start = btrfs_header_bytenr(eb);
381	if (unlikely(found_start != eb->start)) {
382	btrfs_err_rl(fs_info,
383	"bad tree block start, mirror %u want %llu have %llu",
384	eb->read_mirror, eb->start, found_start);
385	ret = -EIO;
386	goto out;
387	}
388	if (unlikely(check_tree_block_fsid(eb))) {
389	btrfs_err_rl(fs_info, "bad fsid on logical %llu mirror %u",
390	eb->start, eb->read_mirror);
391	ret = -EIO;
392	goto out;
393	}
394	found_level = btrfs_header_level(eb);
395	if (unlikely(found_level >= BTRFS_MAX_LEVEL)) {
396	btrfs_err(fs_info,
397	"bad tree block level, mirror %u level %d on logical %llu",
398	eb->read_mirror, btrfs_header_level(eb), eb->start);
399	ret = -EIO;
400	goto out;
401	}
402
403	csum_tree_block(buf: eb, result);
404	header_csum = folio_address(folio: eb->folios[0]) +
405	get_eb_offset_in_folio(eb, offsetof(struct btrfs_header, csum));
406
407	if (memcmp(p: result, q: header_csum, size: csum_size) != 0) {
408	btrfs_warn_rl(fs_info,
409	"checksum verify failed on logical %llu mirror %u wanted " BTRFS_CSUM_FMT " found " BTRFS_CSUM_FMT " level %d%s",
410	eb->start, eb->read_mirror,
411	BTRFS_CSUM_FMT_VALUE(csum_size, header_csum),
412	BTRFS_CSUM_FMT_VALUE(csum_size, result),
413	btrfs_header_level(eb),
414	ignore_csum ? ", ignored" : "");
415	if (unlikely(!ignore_csum)) {
416	ret = -EUCLEAN;
417	goto out;
418	}
419	}
420
421	if (unlikely(found_level != check->level)) {
422	btrfs_err(fs_info,
423	"level verify failed on logical %llu mirror %u wanted %u found %u",
424	eb->start, eb->read_mirror, check->level, found_level);
425	ret = -EIO;
426	goto out;
427	}
428	if (unlikely(check->transid &&
429	btrfs_header_generation(eb) != check->transid)) {
430	btrfs_err_rl(eb->fs_info,
431	"parent transid verify failed on logical %llu mirror %u wanted %llu found %llu",
432	eb->start, eb->read_mirror, check->transid,
433	btrfs_header_generation(eb));
434	ret = -EIO;
435	goto out;
436	}
437	if (check->has_first_key) {
438	const struct btrfs_key *expect_key = &check->first_key;
439	struct btrfs_key found_key;
440
441	if (found_level)
442	btrfs_node_key_to_cpu(eb, cpu_key: &found_key, nr: 0);
443	else
444	btrfs_item_key_to_cpu(eb, cpu_key: &found_key, nr: 0);
445	if (unlikely(btrfs_comp_cpu_keys(expect_key, &found_key))) {
446	btrfs_err(fs_info,
447	"tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
448	eb->start, check->transid,
449	expect_key->objectid,
450	expect_key->type, expect_key->offset,
451	found_key.objectid, found_key.type,
452	found_key.offset);
453	ret = -EUCLEAN;
454	goto out;
455	}
456	}
457	if (check->owner_root) {
458	ret = btrfs_check_eb_owner(eb, root_owner: check->owner_root);
459	if (ret < 0)
460	goto out;
461	}
462
463	/* If this is a leaf block and it is corrupt, just return -EIO. */
464	if (found_level == 0 && btrfs_check_leaf(leaf: eb))
465	ret = -EIO;
466
467	if (found_level > 0 && btrfs_check_node(node: eb))
468	ret = -EIO;
469
470	if (ret)
471	btrfs_err(fs_info,
472	"read time tree block corruption detected on logical %llu mirror %u",
473	eb->start, eb->read_mirror);
474	out:
475	return ret;
476	}
477
478	#ifdef CONFIG_MIGRATION
479	static int btree_migrate_folio(struct address_space *mapping,
480	struct folio *dst, struct folio *src, enum migrate_mode mode)
481	{
482	/*
483	* we can't safely write a btree page from here,
484	* we haven't done the locking hook
485	*/
486	if (folio_test_dirty(folio: src))
487	return -EAGAIN;
488	/*
489	* Buffers may be managed in a filesystem specific way.
490	* We must have no buffers or drop them.
491	*/
492	if (folio_get_private(folio: src) &&
493	!filemap_release_folio(folio: src, GFP_KERNEL))
494	return -EAGAIN;
495	return migrate_folio(mapping, dst, src, mode);
496	}
497	#else
498	#define btree_migrate_folio NULL
499	#endif
500
501	static bool btree_release_folio(struct folio *folio, gfp_t gfp_flags)
502	{
503	if (folio_test_writeback(folio) || folio_test_dirty(folio))
504	return false;
505
506	return try_release_extent_buffer(folio);
507	}
508
509	static void btree_invalidate_folio(struct folio *folio, size_t offset,
510	size_t length)
511	{
512	struct extent_io_tree *tree;
513
514	tree = &folio_to_inode(folio)->io_tree;
515	extent_invalidate_folio(tree, folio, offset);
516	btree_release_folio(folio, GFP_NOFS);
517	if (folio_get_private(folio)) {
518	btrfs_warn(folio_to_fs_info(folio),
519	"folio private not zero on folio %llu",
520	(unsigned long long)folio_pos(folio));
521	folio_detach_private(folio);
522	}
523	}
524
525	#ifdef DEBUG
526	static bool btree_dirty_folio(struct address_space *mapping,
527	struct folio *folio)
528	{
529	struct btrfs_fs_info *fs_info = inode_to_fs_info(mapping->host);
530	struct btrfs_subpage_info *spi = fs_info->subpage_info;
531	struct btrfs_subpage *subpage;
532	struct extent_buffer *eb;
533	int cur_bit = 0;
534	u64 page_start = folio_pos(folio);
535
536	if (fs_info->sectorsize == PAGE_SIZE) {
537	eb = folio_get_private(folio);
538	BUG_ON(!eb);
539	BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
540	BUG_ON(!atomic_read(&eb->refs));
541	btrfs_assert_tree_write_locked(eb);
542	return filemap_dirty_folio(mapping, folio);
543	}
544
545	ASSERT(spi);
546	subpage = folio_get_private(folio);
547
548	for (cur_bit = spi->dirty_offset;
549	cur_bit < spi->dirty_offset + spi->bitmap_nr_bits;
550	cur_bit++) {
551	unsigned long flags;
552	u64 cur;
553
554	spin_lock_irqsave(&subpage->lock, flags);
555	if (!test_bit(cur_bit, subpage->bitmaps)) {
556	spin_unlock_irqrestore(&subpage->lock, flags);
557	continue;
558	}
559	spin_unlock_irqrestore(&subpage->lock, flags);
560	cur = page_start + cur_bit * fs_info->sectorsize;
561
562	eb = find_extent_buffer(fs_info, cur);
563	ASSERT(eb);
564	ASSERT(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
565	ASSERT(atomic_read(&eb->refs));
566	btrfs_assert_tree_write_locked(eb);
567	free_extent_buffer(eb);
568
569	cur_bit += (fs_info->nodesize >> fs_info->sectorsize_bits) - 1;
570	}
571	return filemap_dirty_folio(mapping, folio);
572	}
573	#else
574	#define btree_dirty_folio filemap_dirty_folio
575	#endif
576
577	static const struct address_space_operations btree_aops = {
578	.writepages = btree_writepages,
579	.release_folio = btree_release_folio,
580	.invalidate_folio = btree_invalidate_folio,
581	.migrate_folio = btree_migrate_folio,
582	.dirty_folio = btree_dirty_folio,
583	};
584
585	struct extent_buffer *btrfs_find_create_tree_block(
586	struct btrfs_fs_info *fs_info,
587	u64 bytenr, u64 owner_root,
588	int level)
589	{
590	if (btrfs_is_testing(fs_info))
591	return alloc_test_extent_buffer(fs_info, start: bytenr);
592	return alloc_extent_buffer(fs_info, start: bytenr, owner_root, level);
593	}
594
595	/*
596	* Read tree block at logical address @bytenr and do variant basic but critical
597	* verification.
598	*
599	* @check: expected tree parentness check, see comments of the
600	* structure for details.
601	*/
602	struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
603	struct btrfs_tree_parent_check *check)
604	{
605	struct extent_buffer *buf = NULL;
606	int ret;
607
608	ASSERT(check);
609
610	buf = btrfs_find_create_tree_block(fs_info, bytenr, owner_root: check->owner_root,
611	level: check->level);
612	if (IS_ERR(ptr: buf))
613	return buf;
614
615	ret = btrfs_read_extent_buffer(eb: buf, check);
616	if (ret) {
617	free_extent_buffer_stale(eb: buf);
618	return ERR_PTR(error: ret);
619	}
620	return buf;
621
622	}
623
624	static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info,
625	u64 objectid, gfp_t flags)
626	{
627	struct btrfs_root *root;
628
629	root = kzalloc(sizeof(*root), flags);
630	if (!root)
631	return NULL;
632
633	root->fs_info = fs_info;
634	root->root_key.objectid = objectid;
635	RB_CLEAR_NODE(&root->rb_node);
636
637	xa_init(xa: &root->inodes);
638	xa_init(xa: &root->delayed_nodes);
639
640	btrfs_init_root_block_rsv(root);
641
642	INIT_LIST_HEAD(list: &root->dirty_list);
643	INIT_LIST_HEAD(list: &root->root_list);
644	INIT_LIST_HEAD(list: &root->delalloc_inodes);
645	INIT_LIST_HEAD(list: &root->delalloc_root);
646	INIT_LIST_HEAD(list: &root->ordered_extents);
647	INIT_LIST_HEAD(list: &root->ordered_root);
648	INIT_LIST_HEAD(list: &root->reloc_dirty_list);
649	spin_lock_init(&root->delalloc_lock);
650	spin_lock_init(&root->ordered_extent_lock);
651	spin_lock_init(&root->accounting_lock);
652	spin_lock_init(&root->qgroup_meta_rsv_lock);
653	mutex_init(&root->objectid_mutex);
654	mutex_init(&root->log_mutex);
655	mutex_init(&root->ordered_extent_mutex);
656	mutex_init(&root->delalloc_mutex);
657	init_waitqueue_head(&root->qgroup_flush_wait);
658	init_waitqueue_head(&root->log_writer_wait);
659	init_waitqueue_head(&root->log_commit_wait[0]);
660	init_waitqueue_head(&root->log_commit_wait[1]);
661	INIT_LIST_HEAD(list: &root->log_ctxs[0]);
662	INIT_LIST_HEAD(list: &root->log_ctxs[1]);
663	atomic_set(v: &root->log_commit[0], i: 0);
664	atomic_set(v: &root->log_commit[1], i: 0);
665	atomic_set(v: &root->log_writers, i: 0);
666	atomic_set(v: &root->log_batch, i: 0);
667	refcount_set(r: &root->refs, n: 1);
668	atomic_set(v: &root->snapshot_force_cow, i: 0);
669	atomic_set(v: &root->nr_swapfiles, i: 0);
670	root->log_transid_committed = -1;
671	if (!btrfs_is_testing(fs_info)) {
672	btrfs_extent_io_tree_init(fs_info, tree: &root->dirty_log_pages,
673	owner: IO_TREE_ROOT_DIRTY_LOG_PAGES);
674	btrfs_extent_io_tree_init(fs_info, tree: &root->log_csum_range,
675	owner: IO_TREE_LOG_CSUM_RANGE);
676	}
677
678	spin_lock_init(&root->root_item_lock);
679	btrfs_qgroup_init_swapped_blocks(swapped_blocks: &root->swapped_blocks);
680	#ifdef CONFIG_BTRFS_DEBUG
681	INIT_LIST_HEAD(list: &root->leak_list);
682	spin_lock(lock: &fs_info->fs_roots_radix_lock);
683	list_add_tail(new: &root->leak_list, head: &fs_info->allocated_roots);
684	spin_unlock(lock: &fs_info->fs_roots_radix_lock);
685	#endif
686
687	return root;
688	}
689
690	#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
691	/* Should only be used by the testing infrastructure */
692	struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info)
693	{
694	struct btrfs_root *root;
695
696	if (!fs_info)
697	return ERR_PTR(error: -EINVAL);
698
699	root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID, GFP_KERNEL);
700	if (!root)
701	return ERR_PTR(error: -ENOMEM);
702
703	/* We don't use the stripesize in selftest, set it as sectorsize */
704	root->alloc_bytenr = 0;
705
706	return root;
707	}
708	#endif
709
710	static int global_root_cmp(struct rb_node *a_node, const struct rb_node *b_node)
711	{
712	const struct btrfs_root *a = rb_entry(a_node, struct btrfs_root, rb_node);
713	const struct btrfs_root *b = rb_entry(b_node, struct btrfs_root, rb_node);
714
715	return btrfs_comp_cpu_keys(k1: &a->root_key, k2: &b->root_key);
716	}
717
718	static int global_root_key_cmp(const void *k, const struct rb_node *node)
719	{
720	const struct btrfs_key *key = k;
721	const struct btrfs_root *root = rb_entry(node, struct btrfs_root, rb_node);
722
723	return btrfs_comp_cpu_keys(k1: key, k2: &root->root_key);
724	}
725
726	int btrfs_global_root_insert(struct btrfs_root *root)
727	{
728	struct btrfs_fs_info *fs_info = root->fs_info;
729	struct rb_node *tmp;
730	int ret = 0;
731
732	write_lock(&fs_info->global_root_lock);
733	tmp = rb_find_add(node: &root->rb_node, tree: &fs_info->global_root_tree, cmp: global_root_cmp);
734	write_unlock(&fs_info->global_root_lock);
735
736	if (tmp) {
737	ret = -EEXIST;
738	btrfs_warn(fs_info, "global root %llu %llu already exists",
739	btrfs_root_id(root), root->root_key.offset);
740	}
741	return ret;
742	}
743
744	void btrfs_global_root_delete(struct btrfs_root *root)
745	{
746	struct btrfs_fs_info *fs_info = root->fs_info;
747
748	write_lock(&fs_info->global_root_lock);
749	rb_erase(&root->rb_node, &fs_info->global_root_tree);
750	write_unlock(&fs_info->global_root_lock);
751	}
752
753	struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info,
754	struct btrfs_key *key)
755	{
756	struct rb_node *node;
757	struct btrfs_root *root = NULL;
758
759	read_lock(&fs_info->global_root_lock);
760	node = rb_find(key, tree: &fs_info->global_root_tree, cmp: global_root_key_cmp);
761	if (node)
762	root = container_of(node, struct btrfs_root, rb_node);
763	read_unlock(&fs_info->global_root_lock);
764
765	return root;
766	}
767
768	static u64 btrfs_global_root_id(struct btrfs_fs_info *fs_info, u64 bytenr)
769	{
770	struct btrfs_block_group *block_group;
771	u64 ret;
772
773	if (!btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
774	return 0;
775
776	if (bytenr)
777	block_group = btrfs_lookup_block_group(info: fs_info, bytenr);
778	else
779	block_group = btrfs_lookup_first_block_group(info: fs_info, bytenr);
780	ASSERT(block_group);
781	if (!block_group)
782	return 0;
783	ret = block_group->global_root_id;
784	btrfs_put_block_group(cache: block_group);
785
786	return ret;
787	}
788
789	struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr)
790	{
791	struct btrfs_key key = {
792	.objectid = BTRFS_CSUM_TREE_OBJECTID,
793	.type = BTRFS_ROOT_ITEM_KEY,
794	.offset = btrfs_global_root_id(fs_info, bytenr),
795	};
796
797	return btrfs_global_root(fs_info, key: &key);
798	}
799
800	struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr)
801	{
802	struct btrfs_key key = {
803	.objectid = BTRFS_EXTENT_TREE_OBJECTID,
804	.type = BTRFS_ROOT_ITEM_KEY,
805	.offset = btrfs_global_root_id(fs_info, bytenr),
806	};
807
808	return btrfs_global_root(fs_info, key: &key);
809	}
810
811	struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
812	u64 objectid)
813	{
814	struct btrfs_fs_info *fs_info = trans->fs_info;
815	struct extent_buffer *leaf;
816	struct btrfs_root *tree_root = fs_info->tree_root;
817	struct btrfs_root *root;
818	struct btrfs_key key;
819	unsigned int nofs_flag;
820	int ret = 0;
821
822	/*
823	* We're holding a transaction handle, so use a NOFS memory allocation
824	* context to avoid deadlock if reclaim happens.
825	*/
826	nofs_flag = memalloc_nofs_save();
827	root = btrfs_alloc_root(fs_info, objectid, GFP_KERNEL);
828	memalloc_nofs_restore(flags: nofs_flag);
829	if (!root)
830	return ERR_PTR(error: -ENOMEM);
831
832	root->root_key.objectid = objectid;
833	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
834	root->root_key.offset = 0;
835
836	leaf = btrfs_alloc_tree_block(trans, root, parent: 0, root_objectid: objectid, NULL, level: 0, hint: 0, empty_size: 0,
837	reloc_src_root: 0, nest: BTRFS_NESTING_NORMAL);
838	if (IS_ERR(ptr: leaf)) {
839	ret = PTR_ERR(ptr: leaf);
840	leaf = NULL;
841	goto fail;
842	}
843
844	root->node = leaf;
845	btrfs_mark_buffer_dirty(trans, buf: leaf);
846
847	root->commit_root = btrfs_root_node(root);
848	set_bit(nr: BTRFS_ROOT_TRACK_DIRTY, addr: &root->state);
849
850	btrfs_set_root_flags(s: &root->root_item, val: 0);
851	btrfs_set_root_limit(s: &root->root_item, val: 0);
852	btrfs_set_root_bytenr(s: &root->root_item, val: leaf->start);
853	btrfs_set_root_generation(s: &root->root_item, val: trans->transid);
854	btrfs_set_root_level(s: &root->root_item, val: 0);
855	btrfs_set_root_refs(s: &root->root_item, val: 1);
856	btrfs_set_root_used(s: &root->root_item, val: leaf->len);
857	btrfs_set_root_last_snapshot(s: &root->root_item, val: 0);
858	btrfs_set_root_dirid(s: &root->root_item, val: 0);
859	if (btrfs_is_fstree(rootid: objectid))
860	generate_random_guid(guid: root->root_item.uuid);
861	else
862	export_guid(dst: root->root_item.uuid, src: &guid_null);
863	btrfs_set_root_drop_level(s: &root->root_item, val: 0);
864
865	btrfs_tree_unlock(eb: leaf);
866
867	key.objectid = objectid;
868	key.type = BTRFS_ROOT_ITEM_KEY;
869	key.offset = 0;
870	ret = btrfs_insert_root(trans, root: tree_root, key: &key, item: &root->root_item);
871	if (ret)
872	goto fail;
873
874	return root;
875
876	fail:
877	btrfs_put_root(root);
878
879	return ERR_PTR(error: ret);
880	}
881
882	static struct btrfs_root *alloc_log_tree(struct btrfs_fs_info *fs_info)
883	{
884	struct btrfs_root *root;
885
886	root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID, GFP_NOFS);
887	if (!root)
888	return ERR_PTR(error: -ENOMEM);
889
890	root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
891	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
892	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
893
894	return root;
895	}
896
897	int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
898	struct btrfs_root *root)
899	{
900	struct extent_buffer *leaf;
901
902	/*
903	* DON'T set SHAREABLE bit for log trees.
904	*
905	* Log trees are not exposed to user space thus can't be snapshotted,
906	* and they go away before a real commit is actually done.
907	*
908	* They do store pointers to file data extents, and those reference
909	* counts still get updated (along with back refs to the log tree).
910	*/
911
912	leaf = btrfs_alloc_tree_block(trans, root, parent: 0, BTRFS_TREE_LOG_OBJECTID,
913	NULL, level: 0, hint: 0, empty_size: 0, reloc_src_root: 0, nest: BTRFS_NESTING_NORMAL);
914	if (IS_ERR(ptr: leaf))
915	return PTR_ERR(ptr: leaf);
916
917	root->node = leaf;
918
919	btrfs_mark_buffer_dirty(trans, buf: root->node);
920	btrfs_tree_unlock(eb: root->node);
921
922	return 0;
923	}
924
925	int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
926	struct btrfs_fs_info *fs_info)
927	{
928	struct btrfs_root *log_root;
929
930	log_root = alloc_log_tree(fs_info);
931	if (IS_ERR(ptr: log_root))
932	return PTR_ERR(ptr: log_root);
933
934	if (!btrfs_is_zoned(fs_info)) {
935	int ret = btrfs_alloc_log_tree_node(trans, root: log_root);
936
937	if (ret) {
938	btrfs_put_root(root: log_root);
939	return ret;
940	}
941	}
942
943	WARN_ON(fs_info->log_root_tree);
944	fs_info->log_root_tree = log_root;
945	return 0;
946	}
947
948	int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
949	struct btrfs_root *root)
950	{
951	struct btrfs_fs_info *fs_info = root->fs_info;
952	struct btrfs_root *log_root;
953	struct btrfs_inode_item *inode_item;
954	int ret;
955
956	log_root = alloc_log_tree(fs_info);
957	if (IS_ERR(ptr: log_root))
958	return PTR_ERR(ptr: log_root);
959
960	ret = btrfs_alloc_log_tree_node(trans, root: log_root);
961	if (ret) {
962	btrfs_put_root(root: log_root);
963	return ret;
964	}
965
966	btrfs_set_root_last_trans(root: log_root, transid: trans->transid);
967	log_root->root_key.offset = btrfs_root_id(root);
968
969	inode_item = &log_root->root_item.inode;
970	btrfs_set_stack_inode_generation(s: inode_item, val: 1);
971	btrfs_set_stack_inode_size(s: inode_item, val: 3);
972	btrfs_set_stack_inode_nlink(s: inode_item, val: 1);
973	btrfs_set_stack_inode_nbytes(s: inode_item,
974	val: fs_info->nodesize);
975	btrfs_set_stack_inode_mode(s: inode_item, S_IFDIR | 0755);
976
977	btrfs_set_root_node(item: &log_root->root_item, node: log_root->node);
978
979	WARN_ON(root->log_root);
980	root->log_root = log_root;
981	btrfs_set_root_log_transid(root, log_transid: 0);
982	root->log_transid_committed = -1;
983	btrfs_set_root_last_log_commit(root, commit_id: 0);
984	return 0;
985	}
986
987	static struct btrfs_root *read_tree_root_path(struct btrfs_root *tree_root,
988	struct btrfs_path *path,
989	const struct btrfs_key *key)
990	{
991	struct btrfs_root *root;
992	struct btrfs_tree_parent_check check = { 0 };
993	struct btrfs_fs_info *fs_info = tree_root->fs_info;
994	u64 generation;
995	int ret;
996	int level;
997
998	root = btrfs_alloc_root(fs_info, objectid: key->objectid, GFP_NOFS);
999	if (!root)
1000	return ERR_PTR(error: -ENOMEM);
1001
1002	ret = btrfs_find_root(root: tree_root, search_key: key, path,
1003	root_item: &root->root_item, root_key: &root->root_key);
1004	if (ret) {
1005	if (ret > 0)
1006	ret = -ENOENT;
1007	goto fail;
1008	}
1009
1010	generation = btrfs_root_generation(s: &root->root_item);
1011	level = btrfs_root_level(s: &root->root_item);
1012	check.level = level;
1013	check.transid = generation;
1014	check.owner_root = key->objectid;
1015	root->node = read_tree_block(fs_info, bytenr: btrfs_root_bytenr(s: &root->root_item),
1016	check: &check);
1017	if (IS_ERR(ptr: root->node)) {
1018	ret = PTR_ERR(ptr: root->node);
1019	root->node = NULL;
1020	goto fail;
1021	}
1022	if (unlikely(!btrfs_buffer_uptodate(root->node, generation, false))) {
1023	ret = -EIO;
1024	goto fail;
1025	}
1026
1027	/*
1028	* For real fs, and not log/reloc trees, root owner must
1029	* match its root node owner
1030	*/
1031	if (unlikely(!btrfs_is_testing(fs_info) &&
1032	btrfs_root_id(root) != BTRFS_TREE_LOG_OBJECTID &&
1033	btrfs_root_id(root) != BTRFS_TREE_RELOC_OBJECTID &&
1034	btrfs_root_id(root) != btrfs_header_owner(root->node))) {
1035	btrfs_crit(fs_info,
1036	"root=%llu block=%llu, tree root owner mismatch, have %llu expect %llu",
1037	btrfs_root_id(root), root->node->start,
1038	btrfs_header_owner(root->node),
1039	btrfs_root_id(root));
1040	ret = -EUCLEAN;
1041	goto fail;
1042	}
1043	root->commit_root = btrfs_root_node(root);
1044	return root;
1045	fail:
1046	btrfs_put_root(root);
1047	return ERR_PTR(error: ret);
1048	}
1049
1050	struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
1051	const struct btrfs_key *key)
1052	{
1053	struct btrfs_root *root;
1054	BTRFS_PATH_AUTO_FREE(path);
1055
1056	path = btrfs_alloc_path();
1057	if (!path)
1058	return ERR_PTR(error: -ENOMEM);
1059	root = read_tree_root_path(tree_root, path, key);
1060
1061	return root;
1062	}
1063
1064	/*
1065	* Initialize subvolume root in-memory structure.
1066	*
1067	* @anon_dev: anonymous device to attach to the root, if zero, allocate new
1068	*
1069	* In case of failure the caller is responsible to call btrfs_free_fs_root()
1070	*/
1071	static int btrfs_init_fs_root(struct btrfs_root *root, dev_t anon_dev)
1072	{
1073	int ret;
1074
1075	btrfs_drew_lock_init(lock: &root->snapshot_lock);
1076
1077	if (btrfs_root_id(root) != BTRFS_TREE_LOG_OBJECTID &&
1078	!btrfs_is_data_reloc_root(root) &&
1079	btrfs_is_fstree(rootid: btrfs_root_id(root))) {
1080	set_bit(nr: BTRFS_ROOT_SHAREABLE, addr: &root->state);
1081	btrfs_check_and_init_root_item(item: &root->root_item);
1082	}
1083
1084	/*
1085	* Don't assign anonymous block device to roots that are not exposed to
1086	* userspace, the id pool is limited to 1M
1087	*/
1088	if (btrfs_is_fstree(rootid: btrfs_root_id(root)) &&
1089	btrfs_root_refs(s: &root->root_item) > 0) {
1090	if (!anon_dev) {
1091	ret = get_anon_bdev(&root->anon_dev);
1092	if (ret)
1093	return ret;
1094	} else {
1095	root->anon_dev = anon_dev;
1096	}
1097	}
1098
1099	mutex_lock(&root->objectid_mutex);
1100	ret = btrfs_init_root_free_objectid(root);
1101	if (ret) {
1102	mutex_unlock(lock: &root->objectid_mutex);
1103	return ret;
1104	}
1105
1106	ASSERT(root->free_objectid <= BTRFS_LAST_FREE_OBJECTID);
1107
1108	mutex_unlock(lock: &root->objectid_mutex);
1109
1110	return 0;
1111	}
1112
1113	static struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
1114	u64 root_id)
1115	{
1116	struct btrfs_root *root;
1117
1118	spin_lock(lock: &fs_info->fs_roots_radix_lock);
1119	root = radix_tree_lookup(&fs_info->fs_roots_radix,
1120	(unsigned long)root_id);
1121	root = btrfs_grab_root(root);
1122	spin_unlock(lock: &fs_info->fs_roots_radix_lock);
1123	return root;
1124	}
1125
1126	static struct btrfs_root *btrfs_get_global_root(struct btrfs_fs_info *fs_info,
1127	u64 objectid)
1128	{
1129	struct btrfs_key key = {
1130	.objectid = objectid,
1131	.type = BTRFS_ROOT_ITEM_KEY,
1132	.offset = 0,
1133	};
1134
1135	switch (objectid) {
1136	case BTRFS_ROOT_TREE_OBJECTID:
1137	return btrfs_grab_root(root: fs_info->tree_root);
1138	case BTRFS_EXTENT_TREE_OBJECTID:
1139	return btrfs_grab_root(root: btrfs_global_root(fs_info, key: &key));
1140	case BTRFS_CHUNK_TREE_OBJECTID:
1141	return btrfs_grab_root(root: fs_info->chunk_root);
1142	case BTRFS_DEV_TREE_OBJECTID:
1143	return btrfs_grab_root(root: fs_info->dev_root);
1144	case BTRFS_CSUM_TREE_OBJECTID:
1145	return btrfs_grab_root(root: btrfs_global_root(fs_info, key: &key));
1146	case BTRFS_QUOTA_TREE_OBJECTID:
1147	return btrfs_grab_root(root: fs_info->quota_root);
1148	case BTRFS_UUID_TREE_OBJECTID:
1149	return btrfs_grab_root(root: fs_info->uuid_root);
1150	case BTRFS_BLOCK_GROUP_TREE_OBJECTID:
1151	return btrfs_grab_root(root: fs_info->block_group_root);
1152	case BTRFS_FREE_SPACE_TREE_OBJECTID:
1153	return btrfs_grab_root(root: btrfs_global_root(fs_info, key: &key));
1154	case BTRFS_RAID_STRIPE_TREE_OBJECTID:
1155	return btrfs_grab_root(root: fs_info->stripe_root);
1156	default:
1157	return NULL;
1158	}
1159	}
1160
1161	int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
1162	struct btrfs_root *root)
1163	{
1164	int ret;
1165
1166	ret = radix_tree_preload(GFP_NOFS);
1167	if (ret)
1168	return ret;
1169
1170	spin_lock(lock: &fs_info->fs_roots_radix_lock);
1171	ret = radix_tree_insert(&fs_info->fs_roots_radix,
1172	index: (unsigned long)btrfs_root_id(root),
1173	root);
1174	if (ret == 0) {
1175	btrfs_grab_root(root);
1176	set_bit(nr: BTRFS_ROOT_IN_RADIX, addr: &root->state);
1177	}
1178	spin_unlock(lock: &fs_info->fs_roots_radix_lock);
1179	radix_tree_preload_end();
1180
1181	return ret;
1182	}
1183
1184	void btrfs_check_leaked_roots(const struct btrfs_fs_info *fs_info)
1185	{
1186	#ifdef CONFIG_BTRFS_DEBUG
1187	struct btrfs_root *root;
1188
1189	while (!list_empty(head: &fs_info->allocated_roots)) {
1190	char buf[BTRFS_ROOT_NAME_BUF_LEN];
1191
1192	root = list_first_entry(&fs_info->allocated_roots,
1193	struct btrfs_root, leak_list);
1194	btrfs_err(fs_info, "leaked root %s refcount %d",
1195	btrfs_root_name(&root->root_key, buf),
1196	refcount_read(&root->refs));
1197	WARN_ON_ONCE(1);
1198	while (refcount_read(r: &root->refs) > 1)
1199	btrfs_put_root(root);
1200	btrfs_put_root(root);
1201	}
1202	#endif
1203	}
1204
1205	static void free_global_roots(struct btrfs_fs_info *fs_info)
1206	{
1207	struct btrfs_root *root;
1208	struct rb_node *node;
1209
1210	while ((node = rb_first_postorder(&fs_info->global_root_tree)) != NULL) {
1211	root = rb_entry(node, struct btrfs_root, rb_node);
1212	rb_erase(&root->rb_node, &fs_info->global_root_tree);
1213	btrfs_put_root(root);
1214	}
1215	}
1216
1217	void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
1218	{
1219	struct percpu_counter *em_counter = &fs_info->evictable_extent_maps;
1220
1221	if (fs_info->fs_devices)
1222	btrfs_close_devices(fs_devices: fs_info->fs_devices);
1223	btrfs_free_compress_wsm(fs_info);
1224	percpu_counter_destroy(fbc: &fs_info->stats_read_blocks);
1225	percpu_counter_destroy(fbc: &fs_info->dirty_metadata_bytes);
1226	percpu_counter_destroy(fbc: &fs_info->delalloc_bytes);
1227	percpu_counter_destroy(fbc: &fs_info->ordered_bytes);
1228	if (percpu_counter_initialized(fbc: em_counter))
1229	ASSERT(percpu_counter_sum_positive(em_counter) == 0);
1230	percpu_counter_destroy(fbc: em_counter);
1231	percpu_counter_destroy(fbc: &fs_info->dev_replace.bio_counter);
1232	btrfs_free_csum_hash(fs_info);
1233	btrfs_free_stripe_hash_table(info: fs_info);
1234	btrfs_free_ref_cache(fs_info);
1235	kfree(objp: fs_info->balance_ctl);
1236	kfree(objp: fs_info->delayed_root);
1237	free_global_roots(fs_info);
1238	btrfs_put_root(root: fs_info->tree_root);
1239	btrfs_put_root(root: fs_info->chunk_root);
1240	btrfs_put_root(root: fs_info->dev_root);
1241	btrfs_put_root(root: fs_info->quota_root);
1242	btrfs_put_root(root: fs_info->uuid_root);
1243	btrfs_put_root(root: fs_info->fs_root);
1244	btrfs_put_root(root: fs_info->data_reloc_root);
1245	btrfs_put_root(root: fs_info->block_group_root);
1246	btrfs_put_root(root: fs_info->stripe_root);
1247	btrfs_check_leaked_roots(fs_info);
1248	btrfs_extent_buffer_leak_debug_check(fs_info);
1249	kfree(objp: fs_info->super_copy);
1250	kfree(objp: fs_info->super_for_commit);
1251	kvfree(addr: fs_info);
1252	}
1253
1254
1255	/*
1256	* Get an in-memory reference of a root structure.
1257	*
1258	* For essential trees like root/extent tree, we grab it from fs_info directly.
1259	* For subvolume trees, we check the cached filesystem roots first. If not
1260	* found, then read it from disk and add it to cached fs roots.
1261	*
1262	* Caller should release the root by calling btrfs_put_root() after the usage.
1263	*
1264	* NOTE: Reloc and log trees can't be read by this function as they share the
1265	* same root objectid.
1266	*
1267	* @objectid: root id
1268	* @anon_dev: preallocated anonymous block device number for new roots,
1269	* pass NULL for a new allocation.
1270	* @check_ref: whether to check root item references, If true, return -ENOENT
1271	* for orphan roots
1272	*/
1273	static struct btrfs_root *btrfs_get_root_ref(struct btrfs_fs_info *fs_info,
1274	u64 objectid, dev_t *anon_dev,
1275	bool check_ref)
1276	{
1277	struct btrfs_root *root;
1278	struct btrfs_path *path;
1279	struct btrfs_key key;
1280	int ret;
1281
1282	root = btrfs_get_global_root(fs_info, objectid);
1283	if (root)
1284	return root;
1285
1286	/*
1287	* If we're called for non-subvolume trees, and above function didn't
1288	* find one, do not try to read it from disk.
1289	*
1290	* This is namely for free-space-tree and quota tree, which can change
1291	* at runtime and should only be grabbed from fs_info.
1292	*/
1293	if (!btrfs_is_fstree(rootid: objectid) && objectid != BTRFS_DATA_RELOC_TREE_OBJECTID)
1294	return ERR_PTR(error: -ENOENT);
1295	again:
1296	root = btrfs_lookup_fs_root(fs_info, root_id: objectid);
1297	if (root) {
1298	/*
1299	* Some other caller may have read out the newly inserted
1300	* subvolume already (for things like backref walk etc). Not
1301	* that common but still possible. In that case, we just need
1302	* to free the anon_dev.
1303	*/
1304	if (unlikely(anon_dev && *anon_dev)) {
1305	free_anon_bdev(*anon_dev);
1306	*anon_dev = 0;
1307	}
1308
1309	if (check_ref && btrfs_root_refs(s: &root->root_item) == 0) {
1310	btrfs_put_root(root);
1311	return ERR_PTR(error: -ENOENT);
1312	}
1313	return root;
1314	}
1315
1316	key.objectid = objectid;
1317	key.type = BTRFS_ROOT_ITEM_KEY;
1318	key.offset = (u64)-1;
1319	root = btrfs_read_tree_root(tree_root: fs_info->tree_root, key: &key);
1320	if (IS_ERR(ptr: root))
1321	return root;
1322
1323	if (check_ref && btrfs_root_refs(s: &root->root_item) == 0) {
1324	ret = -ENOENT;
1325	goto fail;
1326	}
1327
1328	ret = btrfs_init_fs_root(root, anon_dev: anon_dev ? *anon_dev : 0);
1329	if (ret)
1330	goto fail;
1331
1332	path = btrfs_alloc_path();
1333	if (!path) {
1334	ret = -ENOMEM;
1335	goto fail;
1336	}
1337	key.objectid = BTRFS_ORPHAN_OBJECTID;
1338	key.type = BTRFS_ORPHAN_ITEM_KEY;
1339	key.offset = objectid;
1340
1341	ret = btrfs_search_slot(NULL, root: fs_info->tree_root, key: &key, p: path, ins_len: 0, cow: 0);
1342	btrfs_free_path(p: path);
1343	if (ret < 0)
1344	goto fail;
1345	if (ret == 0)
1346	set_bit(nr: BTRFS_ROOT_ORPHAN_ITEM_INSERTED, addr: &root->state);
1347
1348	ret = btrfs_insert_fs_root(fs_info, root);
1349	if (ret) {
1350	if (ret == -EEXIST) {
1351	btrfs_put_root(root);
1352	goto again;
1353	}
1354	goto fail;
1355	}
1356	return root;
1357	fail:
1358	/*
1359	* If our caller provided us an anonymous device, then it's his
1360	* responsibility to free it in case we fail. So we have to set our
1361	* root's anon_dev to 0 to avoid a double free, once by btrfs_put_root()
1362	* and once again by our caller.
1363	*/
1364	if (anon_dev && *anon_dev)
1365	root->anon_dev = 0;
1366	btrfs_put_root(root);
1367	return ERR_PTR(error: ret);
1368	}
1369
1370	/*
1371	* Get in-memory reference of a root structure
1372	*
1373	* @objectid: tree objectid
1374	* @check_ref: if set, verify that the tree exists and the item has at least
1375	* one reference
1376	*/
1377	struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
1378	u64 objectid, bool check_ref)
1379	{
1380	return btrfs_get_root_ref(fs_info, objectid, NULL, check_ref);
1381	}
1382
1383	/*
1384	* Get in-memory reference of a root structure, created as new, optionally pass
1385	* the anonymous block device id
1386	*
1387	* @objectid: tree objectid
1388	* @anon_dev: if NULL, allocate a new anonymous block device or use the
1389	* parameter value if not NULL
1390	*/
1391	struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
1392	u64 objectid, dev_t *anon_dev)
1393	{
1394	return btrfs_get_root_ref(fs_info, objectid, anon_dev, check_ref: true);
1395	}
1396
1397	/*
1398	* Return a root for the given objectid.
1399	*
1400	* @fs_info: the fs_info
1401	* @objectid: the objectid we need to lookup
1402	*
1403	* This is exclusively used for backref walking, and exists specifically because
1404	* of how qgroups does lookups. Qgroups will do a backref lookup at delayed ref
1405	* creation time, which means we may have to read the tree_root in order to look
1406	* up a fs root that is not in memory. If the root is not in memory we will
1407	* read the tree root commit root and look up the fs root from there. This is a
1408	* temporary root, it will not be inserted into the radix tree as it doesn't
1409	* have the most uptodate information, it'll simply be discarded once the
1410	* backref code is finished using the root.
1411	*/
1412	struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
1413	struct btrfs_path *path,
1414	u64 objectid)
1415	{
1416	struct btrfs_root *root;
1417	struct btrfs_key key;
1418
1419	ASSERT(path->search_commit_root && path->skip_locking);
1420
1421	/*
1422	* This can return -ENOENT if we ask for a root that doesn't exist, but
1423	* since this is called via the backref walking code we won't be looking
1424	* up a root that doesn't exist, unless there's corruption. So if root
1425	* != NULL just return it.
1426	*/
1427	root = btrfs_get_global_root(fs_info, objectid);
1428	if (root)
1429	return root;
1430
1431	root = btrfs_lookup_fs_root(fs_info, root_id: objectid);
1432	if (root)
1433	return root;
1434
1435	key.objectid = objectid;
1436	key.type = BTRFS_ROOT_ITEM_KEY;
1437	key.offset = (u64)-1;
1438	root = read_tree_root_path(tree_root: fs_info->tree_root, path, key: &key);
1439	btrfs_release_path(p: path);
1440
1441	return root;
1442	}
1443
1444	static int cleaner_kthread(void *arg)
1445	{
1446	struct btrfs_fs_info *fs_info = arg;
1447	int again;
1448
1449	while (1) {
1450	again = 0;
1451
1452	set_bit(nr: BTRFS_FS_CLEANER_RUNNING, addr: &fs_info->flags);
1453
1454	/* Make the cleaner go to sleep early. */
1455	if (btrfs_need_cleaner_sleep(fs_info))
1456	goto sleep;
1457
1458	/*
1459	* Do not do anything if we might cause open_ctree() to block
1460	* before we have finished mounting the filesystem.
1461	*/
1462	if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags))
1463	goto sleep;
1464
1465	if (!mutex_trylock(&fs_info->cleaner_mutex))
1466	goto sleep;
1467
1468	/*
1469	* Avoid the problem that we change the status of the fs
1470	* during the above check and trylock.
1471	*/
1472	if (btrfs_need_cleaner_sleep(fs_info)) {
1473	mutex_unlock(lock: &fs_info->cleaner_mutex);
1474	goto sleep;
1475	}
1476
1477	if (test_and_clear_bit(nr: BTRFS_FS_FEATURE_CHANGED, addr: &fs_info->flags))
1478	btrfs_sysfs_feature_update(fs_info);
1479
1480	btrfs_run_delayed_iputs(fs_info);
1481
1482	again = btrfs_clean_one_deleted_snapshot(fs_info);
1483	mutex_unlock(lock: &fs_info->cleaner_mutex);
1484
1485	/*
1486	* The defragger has dealt with the R/O remount and umount,
1487	* needn't do anything special here.
1488	*/
1489	btrfs_run_defrag_inodes(fs_info);
1490
1491	/*
1492	* Acquires fs_info->reclaim_bgs_lock to avoid racing
1493	* with relocation (btrfs_relocate_chunk) and relocation
1494	* acquires fs_info->cleaner_mutex (btrfs_relocate_block_group)
1495	* after acquiring fs_info->reclaim_bgs_lock. So we
1496	* can't hold, nor need to, fs_info->cleaner_mutex when deleting
1497	* unused block groups.
1498	*/
1499	btrfs_delete_unused_bgs(fs_info);
1500
1501	/*
1502	* Reclaim block groups in the reclaim_bgs list after we deleted
1503	* all unused block_groups. This possibly gives us some more free
1504	* space.
1505	*/
1506	btrfs_reclaim_bgs(fs_info);
1507	sleep:
1508	clear_and_wake_up_bit(bit: BTRFS_FS_CLEANER_RUNNING, word: &fs_info->flags);
1509	if (kthread_should_park())
1510	kthread_parkme();
1511	if (kthread_should_stop())
1512	return 0;
1513	if (!again) {
1514	set_current_state(TASK_INTERRUPTIBLE);
1515	schedule();
1516	__set_current_state(TASK_RUNNING);
1517	}
1518	}
1519	}
1520
1521	static int transaction_kthread(void *arg)
1522	{
1523	struct btrfs_root *root = arg;
1524	struct btrfs_fs_info *fs_info = root->fs_info;
1525	struct btrfs_trans_handle *trans;
1526	struct btrfs_transaction *cur;
1527	u64 transid;
1528	time64_t delta;
1529	unsigned long delay;
1530	bool cannot_commit;
1531
1532	do {
1533	cannot_commit = false;
1534	delay = secs_to_jiffies(fs_info->commit_interval);
1535	mutex_lock(&fs_info->transaction_kthread_mutex);
1536
1537	spin_lock(lock: &fs_info->trans_lock);
1538	cur = fs_info->running_transaction;
1539	if (!cur) {
1540	spin_unlock(lock: &fs_info->trans_lock);
1541	goto sleep;
1542	}
1543
1544	delta = ktime_get_seconds() - cur->start_time;
1545	if (!test_and_clear_bit(nr: BTRFS_FS_COMMIT_TRANS, addr: &fs_info->flags) &&
1546	cur->state < TRANS_STATE_COMMIT_PREP &&
1547	delta < fs_info->commit_interval) {
1548	spin_unlock(lock: &fs_info->trans_lock);
1549	delay -= secs_to_jiffies(delta - 1);
1550	delay = min(delay,
1551	secs_to_jiffies(fs_info->commit_interval));
1552	goto sleep;
1553	}
1554	transid = cur->transid;
1555	spin_unlock(lock: &fs_info->trans_lock);
1556
1557	/* If the file system is aborted, this will always fail. */
1558	trans = btrfs_attach_transaction(root);
1559	if (IS_ERR(ptr: trans)) {
1560	if (PTR_ERR(ptr: trans) != -ENOENT)
1561	cannot_commit = true;
1562	goto sleep;
1563	}
1564	if (transid == trans->transid) {
1565	btrfs_commit_transaction(trans);
1566	} else {
1567	btrfs_end_transaction(trans);
1568	}
1569	sleep:
1570	wake_up_process(tsk: fs_info->cleaner_kthread);
1571	mutex_unlock(lock: &fs_info->transaction_kthread_mutex);
1572
1573	if (BTRFS_FS_ERROR(fs_info))
1574	btrfs_cleanup_transaction(fs_info);
1575	if (!kthread_should_stop() &&
1576	(!btrfs_transaction_blocked(info: fs_info) ||
1577	cannot_commit))
1578	schedule_timeout_interruptible(timeout: delay);
1579	} while (!kthread_should_stop());
1580	return 0;
1581	}
1582
1583	/*
1584	* This will find the highest generation in the array of root backups. The
1585	* index of the highest array is returned, or -EINVAL if we can't find
1586	* anything.
1587	*
1588	* We check to make sure the array is valid by comparing the
1589	* generation of the latest root in the array with the generation
1590	* in the super block. If they don't match we pitch it.
1591	*/
1592	static int find_newest_super_backup(struct btrfs_fs_info *info)
1593	{
1594	const u64 newest_gen = btrfs_super_generation(s: info->super_copy);
1595	u64 cur;
1596	struct btrfs_root_backup *root_backup;
1597	int i;
1598
1599	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
1600	root_backup = info->super_copy->super_roots + i;
1601	cur = btrfs_backup_tree_root_gen(s: root_backup);
1602	if (cur == newest_gen)
1603	return i;
1604	}
1605
1606	return -EINVAL;
1607	}
1608
1609	/*
1610	* copy all the root pointers into the super backup array.
1611	* this will bump the backup pointer by one when it is
1612	* done
1613	*/
1614	static void backup_super_roots(struct btrfs_fs_info *info)
1615	{
1616	const int next_backup = info->backup_root_index;
1617	struct btrfs_root_backup *root_backup;
1618
1619	root_backup = info->super_for_commit->super_roots + next_backup;
1620
1621	/*
1622	* make sure all of our padding and empty slots get zero filled
1623	* regardless of which ones we use today
1624	*/
1625	memset(root_backup, 0, sizeof(*root_backup));
1626
1627	info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
1628
1629	btrfs_set_backup_tree_root(s: root_backup, val: info->tree_root->node->start);
1630	btrfs_set_backup_tree_root_gen(s: root_backup,
1631	val: btrfs_header_generation(eb: info->tree_root->node));
1632
1633	btrfs_set_backup_tree_root_level(s: root_backup,
1634	val: btrfs_header_level(eb: info->tree_root->node));
1635
1636	btrfs_set_backup_chunk_root(s: root_backup, val: info->chunk_root->node->start);
1637	btrfs_set_backup_chunk_root_gen(s: root_backup,
1638	val: btrfs_header_generation(eb: info->chunk_root->node));
1639	btrfs_set_backup_chunk_root_level(s: root_backup,
1640	val: btrfs_header_level(eb: info->chunk_root->node));
1641
1642	if (!btrfs_fs_incompat(info, EXTENT_TREE_V2)) {
1643	struct btrfs_root *extent_root = btrfs_extent_root(fs_info: info, bytenr: 0);
1644	struct btrfs_root *csum_root = btrfs_csum_root(fs_info: info, bytenr: 0);
1645
1646	btrfs_set_backup_extent_root(s: root_backup,
1647	val: extent_root->node->start);
1648	btrfs_set_backup_extent_root_gen(s: root_backup,
1649	val: btrfs_header_generation(eb: extent_root->node));
1650	btrfs_set_backup_extent_root_level(s: root_backup,
1651	val: btrfs_header_level(eb: extent_root->node));
1652
1653	btrfs_set_backup_csum_root(s: root_backup, val: csum_root->node->start);
1654	btrfs_set_backup_csum_root_gen(s: root_backup,
1655	val: btrfs_header_generation(eb: csum_root->node));
1656	btrfs_set_backup_csum_root_level(s: root_backup,
1657	val: btrfs_header_level(eb: csum_root->node));
1658	}
1659
1660	/*
1661	* we might commit during log recovery, which happens before we set
1662	* the fs_root. Make sure it is valid before we fill it in.
1663	*/
1664	if (info->fs_root && info->fs_root->node) {
1665	btrfs_set_backup_fs_root(s: root_backup,
1666	val: info->fs_root->node->start);
1667	btrfs_set_backup_fs_root_gen(s: root_backup,
1668	val: btrfs_header_generation(eb: info->fs_root->node));
1669	btrfs_set_backup_fs_root_level(s: root_backup,
1670	val: btrfs_header_level(eb: info->fs_root->node));
1671	}
1672
1673	btrfs_set_backup_dev_root(s: root_backup, val: info->dev_root->node->start);
1674	btrfs_set_backup_dev_root_gen(s: root_backup,
1675	val: btrfs_header_generation(eb: info->dev_root->node));
1676	btrfs_set_backup_dev_root_level(s: root_backup,
1677	val: btrfs_header_level(eb: info->dev_root->node));
1678
1679	btrfs_set_backup_total_bytes(s: root_backup,
1680	val: btrfs_super_total_bytes(s: info->super_copy));
1681	btrfs_set_backup_bytes_used(s: root_backup,
1682	val: btrfs_super_bytes_used(s: info->super_copy));
1683	btrfs_set_backup_num_devices(s: root_backup,
1684	val: btrfs_super_num_devices(s: info->super_copy));
1685
1686	/*
1687	* if we don't copy this out to the super_copy, it won't get remembered
1688	* for the next commit
1689	*/
1690	memcpy(&info->super_copy->super_roots,
1691	&info->super_for_commit->super_roots,
1692	sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
1693	}
1694
1695	/*
1696	* Reads a backup root based on the passed priority. Prio 0 is the newest, prio
1697	* 1/2/3 are 2nd newest/3rd newest/4th (oldest) backup roots
1698	*
1699	* @fs_info: filesystem whose backup roots need to be read
1700	* @priority: priority of backup root required
1701	*
1702	* Returns backup root index on success and -EINVAL otherwise.
1703	*/
1704	static int read_backup_root(struct btrfs_fs_info *fs_info, u8 priority)
1705	{
1706	int backup_index = find_newest_super_backup(info: fs_info);
1707	struct btrfs_super_block *super = fs_info->super_copy;
1708	struct btrfs_root_backup *root_backup;
1709
1710	if (priority < BTRFS_NUM_BACKUP_ROOTS && backup_index >= 0) {
1711	if (priority == 0)
1712	return backup_index;
1713
1714	backup_index = backup_index + BTRFS_NUM_BACKUP_ROOTS - priority;
1715	backup_index %= BTRFS_NUM_BACKUP_ROOTS;
1716	} else {
1717	return -EINVAL;
1718	}
1719
1720	root_backup = super->super_roots + backup_index;
1721
1722	btrfs_set_super_generation(s: super,
1723	val: btrfs_backup_tree_root_gen(s: root_backup));
1724	btrfs_set_super_root(s: super, val: btrfs_backup_tree_root(s: root_backup));
1725	btrfs_set_super_root_level(s: super,
1726	val: btrfs_backup_tree_root_level(s: root_backup));
1727	btrfs_set_super_bytes_used(s: super, val: btrfs_backup_bytes_used(s: root_backup));
1728
1729	/*
1730	* Fixme: the total bytes and num_devices need to match or we should
1731	* need a fsck
1732	*/
1733	btrfs_set_super_total_bytes(s: super, val: btrfs_backup_total_bytes(s: root_backup));
1734	btrfs_set_super_num_devices(s: super, val: btrfs_backup_num_devices(s: root_backup));
1735
1736	return backup_index;
1737	}
1738
1739	/* helper to cleanup workers */
1740	static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
1741	{
1742	btrfs_destroy_workqueue(wq: fs_info->fixup_workers);
1743	btrfs_destroy_workqueue(wq: fs_info->delalloc_workers);
1744	btrfs_destroy_workqueue(wq: fs_info->workers);
1745	if (fs_info->endio_workers)
1746	destroy_workqueue(wq: fs_info->endio_workers);
1747	if (fs_info->rmw_workers)
1748	destroy_workqueue(wq: fs_info->rmw_workers);
1749	btrfs_destroy_workqueue(wq: fs_info->endio_write_workers);
1750	btrfs_destroy_workqueue(wq: fs_info->endio_freespace_worker);
1751	btrfs_destroy_workqueue(wq: fs_info->delayed_workers);
1752	btrfs_destroy_workqueue(wq: fs_info->caching_workers);
1753	btrfs_destroy_workqueue(wq: fs_info->flush_workers);
1754	btrfs_destroy_workqueue(wq: fs_info->qgroup_rescan_workers);
1755	if (fs_info->discard_ctl.discard_workers)
1756	destroy_workqueue(wq: fs_info->discard_ctl.discard_workers);
1757	/*
1758	* Now that all other work queues are destroyed, we can safely destroy
1759	* the queues used for metadata I/O, since tasks from those other work
1760	* queues can do metadata I/O operations.
1761	*/
1762	if (fs_info->endio_meta_workers)
1763	destroy_workqueue(wq: fs_info->endio_meta_workers);
1764	}
1765
1766	static void free_root_extent_buffers(struct btrfs_root *root)
1767	{
1768	if (root) {
1769	free_extent_buffer(eb: root->node);
1770	free_extent_buffer(eb: root->commit_root);
1771	root->node = NULL;
1772	root->commit_root = NULL;
1773	}
1774	}
1775
1776	static void free_global_root_pointers(struct btrfs_fs_info *fs_info)
1777	{
1778	struct btrfs_root *root, *tmp;
1779
1780	rbtree_postorder_for_each_entry_safe(root, tmp,
1781	&fs_info->global_root_tree,
1782	rb_node)
1783	free_root_extent_buffers(root);
1784	}
1785
1786	/* helper to cleanup tree roots */
1787	static void free_root_pointers(struct btrfs_fs_info *info, bool free_chunk_root)
1788	{
1789	free_root_extent_buffers(root: info->tree_root);
1790
1791	free_global_root_pointers(fs_info: info);
1792	free_root_extent_buffers(root: info->dev_root);
1793	free_root_extent_buffers(root: info->quota_root);
1794	free_root_extent_buffers(root: info->uuid_root);
1795	free_root_extent_buffers(root: info->fs_root);
1796	free_root_extent_buffers(root: info->data_reloc_root);
1797	free_root_extent_buffers(root: info->block_group_root);
1798	free_root_extent_buffers(root: info->stripe_root);
1799	if (free_chunk_root)
1800	free_root_extent_buffers(root: info->chunk_root);
1801	}
1802
1803	void btrfs_put_root(struct btrfs_root *root)
1804	{
1805	if (!root)
1806	return;
1807
1808	if (refcount_dec_and_test(r: &root->refs)) {
1809	if (WARN_ON(!xa_empty(&root->inodes)))
1810	xa_destroy(&root->inodes);
1811	if (WARN_ON(!xa_empty(&root->delayed_nodes)))
1812	xa_destroy(&root->delayed_nodes);
1813	WARN_ON(test_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state));
1814	if (root->anon_dev)
1815	free_anon_bdev(root->anon_dev);
1816	free_root_extent_buffers(root);
1817	#ifdef CONFIG_BTRFS_DEBUG
1818	spin_lock(lock: &root->fs_info->fs_roots_radix_lock);
1819	list_del_init(entry: &root->leak_list);
1820	spin_unlock(lock: &root->fs_info->fs_roots_radix_lock);
1821	#endif
1822	kfree(objp: root);
1823	}
1824	}
1825
1826	void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info)
1827	{
1828	int ret;
1829	struct btrfs_root *gang[8];
1830	int i;
1831
1832	while (!list_empty(head: &fs_info->dead_roots)) {
1833	gang[0] = list_first_entry(&fs_info->dead_roots,
1834	struct btrfs_root, root_list);
1835	list_del(entry: &gang[0]->root_list);
1836
1837	if (test_bit(BTRFS_ROOT_IN_RADIX, &gang[0]->state))
1838	btrfs_drop_and_free_fs_root(fs_info, root: gang[0]);
1839	btrfs_put_root(root: gang[0]);
1840	}
1841
1842	while (1) {
1843	ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
1844	results: (void **)gang, first_index: 0,
1845	ARRAY_SIZE(gang));
1846	if (!ret)
1847	break;
1848	for (i = 0; i < ret; i++)
1849	btrfs_drop_and_free_fs_root(fs_info, root: gang[i]);
1850	}
1851	}
1852
1853	static void btrfs_init_scrub(struct btrfs_fs_info *fs_info)
1854	{
1855	mutex_init(&fs_info->scrub_lock);
1856	atomic_set(v: &fs_info->scrubs_running, i: 0);
1857	atomic_set(v: &fs_info->scrub_pause_req, i: 0);
1858	atomic_set(v: &fs_info->scrubs_paused, i: 0);
1859	atomic_set(v: &fs_info->scrub_cancel_req, i: 0);
1860	init_waitqueue_head(&fs_info->scrub_pause_wait);
1861	refcount_set(r: &fs_info->scrub_workers_refcnt, n: 0);
1862	}
1863
1864	static void btrfs_init_balance(struct btrfs_fs_info *fs_info)
1865	{
1866	spin_lock_init(&fs_info->balance_lock);
1867	mutex_init(&fs_info->balance_mutex);
1868	atomic_set(v: &fs_info->balance_pause_req, i: 0);
1869	atomic_set(v: &fs_info->balance_cancel_req, i: 0);
1870	fs_info->balance_ctl = NULL;
1871	init_waitqueue_head(&fs_info->balance_wait_q);
1872	atomic_set(v: &fs_info->reloc_cancel_req, i: 0);
1873	}
1874
1875	static int btrfs_init_btree_inode(struct super_block *sb)
1876	{
1877	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
1878	unsigned long hash = btrfs_inode_hash(BTRFS_BTREE_INODE_OBJECTID,
1879	root: fs_info->tree_root);
1880	struct inode *inode;
1881
1882	inode = new_inode(sb);
1883	if (!inode)
1884	return -ENOMEM;
1885
1886	btrfs_set_inode_number(BTRFS_I(inode), BTRFS_BTREE_INODE_OBJECTID);
1887	set_nlink(inode, nlink: 1);
1888	/*
1889	* we set the i_size on the btree inode to the max possible int.
1890	* the real end of the address space is determined by all of
1891	* the devices in the system
1892	*/
1893	inode->i_size = OFFSET_MAX;
1894	inode->i_mapping->a_ops = &btree_aops;
1895	mapping_set_gfp_mask(m: inode->i_mapping, GFP_NOFS);
1896
1897	btrfs_extent_io_tree_init(fs_info, tree: &BTRFS_I(inode)->io_tree,
1898	owner: IO_TREE_BTREE_INODE_IO);
1899	btrfs_extent_map_tree_init(tree: &BTRFS_I(inode)->extent_tree);
1900
1901	BTRFS_I(inode)->root = btrfs_grab_root(root: fs_info->tree_root);
1902	set_bit(nr: BTRFS_INODE_DUMMY, addr: &BTRFS_I(inode)->runtime_flags);
1903	__insert_inode_hash(inode, hashval: hash);
1904	set_bit(nr: AS_KERNEL_FILE, addr: &inode->i_mapping->flags);
1905	fs_info->btree_inode = inode;
1906
1907	return 0;
1908	}
1909
1910	static void btrfs_init_dev_replace_locks(struct btrfs_fs_info *fs_info)
1911	{
1912	mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount);
1913	init_rwsem(&fs_info->dev_replace.rwsem);
1914	init_waitqueue_head(&fs_info->dev_replace.replace_wait);
1915	}
1916
1917	static void btrfs_init_qgroup(struct btrfs_fs_info *fs_info)
1918	{
1919	spin_lock_init(&fs_info->qgroup_lock);
1920	mutex_init(&fs_info->qgroup_ioctl_lock);
1921	fs_info->qgroup_tree = RB_ROOT;
1922	INIT_LIST_HEAD(list: &fs_info->dirty_qgroups);
1923	fs_info->qgroup_seq = 1;
1924	fs_info->qgroup_rescan_running = false;
1925	fs_info->qgroup_drop_subtree_thres = BTRFS_QGROUP_DROP_SUBTREE_THRES_DEFAULT;
1926	mutex_init(&fs_info->qgroup_rescan_lock);
1927	}
1928
1929	static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info)
1930	{
1931	u32 max_active = fs_info->thread_pool_size;
1932	unsigned int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND;
1933	unsigned int ordered_flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_PERCPU;
1934
1935	fs_info->workers =
1936	btrfs_alloc_workqueue(fs_info, name: "worker", flags, limit_active: max_active, thresh: 16);
1937
1938	fs_info->delalloc_workers =
1939	btrfs_alloc_workqueue(fs_info, name: "delalloc",
1940	flags, limit_active: max_active, thresh: 2);
1941
1942	fs_info->flush_workers =
1943	btrfs_alloc_workqueue(fs_info, name: "flush_delalloc",
1944	flags, limit_active: max_active, thresh: 0);
1945
1946	fs_info->caching_workers =
1947	btrfs_alloc_workqueue(fs_info, name: "cache", flags, limit_active: max_active, thresh: 0);
1948
1949	fs_info->fixup_workers =
1950	btrfs_alloc_ordered_workqueue(fs_info, name: "fixup", flags: ordered_flags);
1951
1952	fs_info->endio_workers =
1953	alloc_workqueue("btrfs-endio", flags, max_active);
1954	fs_info->endio_meta_workers =
1955	alloc_workqueue("btrfs-endio-meta", flags, max_active);
1956	fs_info->rmw_workers = alloc_workqueue("btrfs-rmw", flags, max_active);
1957	fs_info->endio_write_workers =
1958	btrfs_alloc_workqueue(fs_info, name: "endio-write", flags,
1959	limit_active: max_active, thresh: 2);
1960	fs_info->endio_freespace_worker =
1961	btrfs_alloc_workqueue(fs_info, name: "freespace-write", flags,
1962	limit_active: max_active, thresh: 0);
1963	fs_info->delayed_workers =
1964	btrfs_alloc_workqueue(fs_info, name: "delayed-meta", flags,
1965	limit_active: max_active, thresh: 0);
1966	fs_info->qgroup_rescan_workers =
1967	btrfs_alloc_ordered_workqueue(fs_info, name: "qgroup-rescan",
1968	flags: ordered_flags);
1969	fs_info->discard_ctl.discard_workers =
1970	alloc_ordered_workqueue("btrfs-discard", WQ_FREEZABLE);
1971
1972	if (!(fs_info->workers &&
1973	fs_info->delalloc_workers && fs_info->flush_workers &&
1974	fs_info->endio_workers && fs_info->endio_meta_workers &&
1975	fs_info->endio_write_workers &&
1976	fs_info->endio_freespace_worker && fs_info->rmw_workers &&
1977	fs_info->caching_workers && fs_info->fixup_workers &&
1978	fs_info->delayed_workers && fs_info->qgroup_rescan_workers &&
1979	fs_info->discard_ctl.discard_workers)) {
1980	return -ENOMEM;
1981	}
1982
1983	return 0;
1984	}
1985
1986	static int btrfs_init_csum_hash(struct btrfs_fs_info *fs_info, u16 csum_type)
1987	{
1988	struct crypto_shash *csum_shash;
1989	const char *csum_driver = btrfs_super_csum_driver(csum_type);
1990
1991	csum_shash = crypto_alloc_shash(alg_name: csum_driver, type: 0, mask: 0);
1992
1993	if (IS_ERR(ptr: csum_shash)) {
1994	btrfs_err(fs_info, "error allocating %s hash for checksum",
1995	csum_driver);
1996	return PTR_ERR(ptr: csum_shash);
1997	}
1998
1999	fs_info->csum_shash = csum_shash;
2000
2001	/* Check if the checksum implementation is a fast accelerated one. */
2002	switch (csum_type) {
2003	case BTRFS_CSUM_TYPE_CRC32:
2004	if (crc32_optimizations() & CRC32C_OPTIMIZATION)
2005	set_bit(nr: BTRFS_FS_CSUM_IMPL_FAST, addr: &fs_info->flags);
2006	break;
2007	case BTRFS_CSUM_TYPE_XXHASH:
2008	set_bit(nr: BTRFS_FS_CSUM_IMPL_FAST, addr: &fs_info->flags);
2009	break;
2010	default:
2011	break;
2012	}
2013
2014	btrfs_info(fs_info, "using %s (%s) checksum algorithm",
2015	btrfs_super_csum_name(csum_type),
2016	crypto_shash_driver_name(csum_shash));
2017	return 0;
2018	}
2019
2020	static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
2021	struct btrfs_fs_devices *fs_devices)
2022	{
2023	int ret;
2024	struct btrfs_tree_parent_check check = { 0 };
2025	struct btrfs_root *log_tree_root;
2026	struct btrfs_super_block *disk_super = fs_info->super_copy;
2027	u64 bytenr = btrfs_super_log_root(s: disk_super);
2028	int level = btrfs_super_log_root_level(s: disk_super);
2029
2030	if (unlikely(fs_devices->rw_devices == 0)) {
2031	btrfs_warn(fs_info, "log replay required on RO media");
2032	return -EIO;
2033	}
2034
2035	log_tree_root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID,
2036	GFP_KERNEL);
2037	if (!log_tree_root)
2038	return -ENOMEM;
2039
2040	check.level = level;
2041	check.transid = fs_info->generation + 1;
2042	check.owner_root = BTRFS_TREE_LOG_OBJECTID;
2043	log_tree_root->node = read_tree_block(fs_info, bytenr, check: &check);
2044	if (IS_ERR(ptr: log_tree_root->node)) {
2045	btrfs_warn(fs_info, "failed to read log tree");
2046	ret = PTR_ERR(ptr: log_tree_root->node);
2047	log_tree_root->node = NULL;
2048	btrfs_put_root(root: log_tree_root);
2049	return ret;
2050	}
2051	if (unlikely(!extent_buffer_uptodate(log_tree_root->node))) {
2052	btrfs_err(fs_info, "failed to read log tree");
2053	btrfs_put_root(root: log_tree_root);
2054	return -EIO;
2055	}
2056
2057	/* returns with log_tree_root freed on success */
2058	ret = btrfs_recover_log_trees(tree_root: log_tree_root);
2059	btrfs_put_root(root: log_tree_root);
2060	if (ret) {
2061	btrfs_handle_fs_error(fs_info, ret,
2062	"Failed to recover log tree");
2063	return ret;
2064	}
2065
2066	if (sb_rdonly(sb: fs_info->sb)) {
2067	ret = btrfs_commit_super(fs_info);
2068	if (ret)
2069	return ret;
2070	}
2071
2072	return 0;
2073	}
2074
2075	static int load_global_roots_objectid(struct btrfs_root *tree_root,
2076	struct btrfs_path *path, u64 objectid,
2077	const char *name)
2078	{
2079	struct btrfs_fs_info *fs_info = tree_root->fs_info;
2080	struct btrfs_root *root;
2081	u64 max_global_id = 0;
2082	int ret;
2083	struct btrfs_key key = {
2084	.objectid = objectid,
2085	.type = BTRFS_ROOT_ITEM_KEY,
2086	.offset = 0,
2087	};
2088	bool found = false;
2089
2090	/* If we have IGNOREDATACSUMS skip loading these roots. */
2091	if (objectid == BTRFS_CSUM_TREE_OBJECTID &&
2092	btrfs_test_opt(fs_info, IGNOREDATACSUMS)) {
2093	set_bit(nr: BTRFS_FS_STATE_NO_DATA_CSUMS, addr: &fs_info->fs_state);
2094	return 0;
2095	}
2096
2097	while (1) {
2098	ret = btrfs_search_slot(NULL, root: tree_root, key: &key, p: path, ins_len: 0, cow: 0);
2099	if (ret < 0)
2100	break;
2101
2102	if (path->slots[0] >= btrfs_header_nritems(eb: path->nodes[0])) {
2103	ret = btrfs_next_leaf(root: tree_root, path);
2104	if (ret) {
2105	if (ret > 0)
2106	ret = 0;
2107	break;
2108	}
2109	}
2110	ret = 0;
2111
2112	btrfs_item_key_to_cpu(eb: path->nodes[0], cpu_key: &key, nr: path->slots[0]);
2113	if (key.objectid != objectid)
2114	break;
2115	btrfs_release_path(p: path);
2116
2117	/*
2118	* Just worry about this for extent tree, it'll be the same for
2119	* everybody.
2120	*/
2121	if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
2122	max_global_id = max(max_global_id, key.offset);
2123
2124	found = true;
2125	root = read_tree_root_path(tree_root, path, key: &key);
2126	if (IS_ERR(ptr: root)) {
2127	ret = PTR_ERR(ptr: root);
2128	break;
2129	}
2130	set_bit(nr: BTRFS_ROOT_TRACK_DIRTY, addr: &root->state);
2131	ret = btrfs_global_root_insert(root);
2132	if (ret) {
2133	btrfs_put_root(root);
2134	break;
2135	}
2136	key.offset++;
2137	}
2138	btrfs_release_path(p: path);
2139
2140	if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
2141	fs_info->nr_global_roots = max_global_id + 1;
2142
2143	if (!found || ret) {
2144	if (objectid == BTRFS_CSUM_TREE_OBJECTID)
2145	set_bit(nr: BTRFS_FS_STATE_NO_DATA_CSUMS, addr: &fs_info->fs_state);
2146
2147	if (!btrfs_test_opt(fs_info, IGNOREBADROOTS))
2148	ret = ret ? ret : -ENOENT;
2149	else
2150	ret = 0;
2151	btrfs_err(fs_info, "failed to load root %s", name);
2152	}
2153	return ret;
2154	}
2155
2156	static int load_global_roots(struct btrfs_root *tree_root)
2157	{
2158	BTRFS_PATH_AUTO_FREE(path);
2159	int ret;
2160
2161	path = btrfs_alloc_path();
2162	if (!path)
2163	return -ENOMEM;
2164
2165	ret = load_global_roots_objectid(tree_root, path,
2166	BTRFS_EXTENT_TREE_OBJECTID, name: "extent");
2167	if (ret)
2168	return ret;
2169	ret = load_global_roots_objectid(tree_root, path,
2170	BTRFS_CSUM_TREE_OBJECTID, name: "csum");
2171	if (ret)
2172	return ret;
2173	if (!btrfs_fs_compat_ro(tree_root->fs_info, FREE_SPACE_TREE))
2174	return ret;
2175	ret = load_global_roots_objectid(tree_root, path,
2176	BTRFS_FREE_SPACE_TREE_OBJECTID,
2177	name: "free space");
2178
2179	return ret;
2180	}
2181
2182	static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
2183	{
2184	struct btrfs_root *tree_root = fs_info->tree_root;
2185	struct btrfs_root *root;
2186	struct btrfs_key location;
2187	int ret;
2188
2189	ASSERT(fs_info->tree_root);
2190
2191	ret = load_global_roots(tree_root);
2192	if (ret)
2193	return ret;
2194
2195	location.type = BTRFS_ROOT_ITEM_KEY;
2196	location.offset = 0;
2197
2198	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE)) {
2199	location.objectid = BTRFS_BLOCK_GROUP_TREE_OBJECTID;
2200	root = btrfs_read_tree_root(tree_root, key: &location);
2201	if (IS_ERR(ptr: root)) {
2202	if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2203	ret = PTR_ERR(ptr: root);
2204	goto out;
2205	}
2206	} else {
2207	set_bit(nr: BTRFS_ROOT_TRACK_DIRTY, addr: &root->state);
2208	fs_info->block_group_root = root;
2209	}
2210	}
2211
2212	location.objectid = BTRFS_DEV_TREE_OBJECTID;
2213	root = btrfs_read_tree_root(tree_root, key: &location);
2214	if (IS_ERR(ptr: root)) {
2215	if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2216	ret = PTR_ERR(ptr: root);
2217	goto out;
2218	}
2219	} else {
2220	set_bit(nr: BTRFS_ROOT_TRACK_DIRTY, addr: &root->state);
2221	fs_info->dev_root = root;
2222	}
2223	/* Initialize fs_info for all devices in any case */
2224	ret = btrfs_init_devices_late(fs_info);
2225	if (ret)
2226	goto out;
2227
2228	/*
2229	* This tree can share blocks with some other fs tree during relocation
2230	* and we need a proper setup by btrfs_get_fs_root
2231	*/
2232	root = btrfs_get_fs_root(fs_info: tree_root->fs_info,
2233	BTRFS_DATA_RELOC_TREE_OBJECTID, check_ref: true);
2234	if (IS_ERR(ptr: root)) {
2235	if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2236	location.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
2237	ret = PTR_ERR(ptr: root);
2238	goto out;
2239	}
2240	} else {
2241	set_bit(nr: BTRFS_ROOT_TRACK_DIRTY, addr: &root->state);
2242	fs_info->data_reloc_root = root;
2243	}
2244
2245	location.objectid = BTRFS_QUOTA_TREE_OBJECTID;
2246	root = btrfs_read_tree_root(tree_root, key: &location);
2247	if (!IS_ERR(ptr: root)) {
2248	set_bit(nr: BTRFS_ROOT_TRACK_DIRTY, addr: &root->state);
2249	fs_info->quota_root = root;
2250	}
2251
2252	location.objectid = BTRFS_UUID_TREE_OBJECTID;
2253	root = btrfs_read_tree_root(tree_root, key: &location);
2254	if (IS_ERR(ptr: root)) {
2255	if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2256	ret = PTR_ERR(ptr: root);
2257	if (ret != -ENOENT)
2258	goto out;
2259	}
2260	} else {
2261	set_bit(nr: BTRFS_ROOT_TRACK_DIRTY, addr: &root->state);
2262	fs_info->uuid_root = root;
2263	}
2264
2265	if (btrfs_fs_incompat(fs_info, RAID_STRIPE_TREE)) {
2266	location.objectid = BTRFS_RAID_STRIPE_TREE_OBJECTID;
2267	root = btrfs_read_tree_root(tree_root, key: &location);
2268	if (IS_ERR(ptr: root)) {
2269	if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2270	ret = PTR_ERR(ptr: root);
2271	goto out;
2272	}
2273	} else {
2274	set_bit(nr: BTRFS_ROOT_TRACK_DIRTY, addr: &root->state);
2275	fs_info->stripe_root = root;
2276	}
2277	}
2278
2279	return 0;
2280	out:
2281	btrfs_warn(fs_info, "failed to read root (objectid=%llu): %d",
2282	location.objectid, ret);
2283	return ret;
2284	}
2285
2286	static int validate_sys_chunk_array(const struct btrfs_fs_info *fs_info,
2287	const struct btrfs_super_block *sb)
2288	{
2289	unsigned int cur = 0; /* Offset inside the sys chunk array */
2290	/*
2291	* At sb read time, fs_info is not fully initialized. Thus we have
2292	* to use super block sectorsize, which should have been validated.
2293	*/
2294	const u32 sectorsize = btrfs_super_sectorsize(s: sb);
2295	u32 sys_array_size = btrfs_super_sys_array_size(s: sb);
2296
2297	if (unlikely(sys_array_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE)) {
2298	btrfs_err(fs_info, "system chunk array too big %u > %u",
2299	sys_array_size, BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
2300	return -EUCLEAN;
2301	}
2302
2303	while (cur < sys_array_size) {
2304	struct btrfs_disk_key *disk_key;
2305	struct btrfs_chunk *chunk;
2306	struct btrfs_key key;
2307	u64 type;
2308	u16 num_stripes;
2309	u32 len;
2310	int ret;
2311
2312	disk_key = (struct btrfs_disk_key *)(sb->sys_chunk_array + cur);
2313	len = sizeof(*disk_key);
2314
2315	if (unlikely(cur + len > sys_array_size))
2316	goto short_read;
2317	cur += len;
2318
2319	btrfs_disk_key_to_cpu(cpu_key: &key, disk_key);
2320	if (unlikely(key.type != BTRFS_CHUNK_ITEM_KEY)) {
2321	btrfs_err(fs_info,
2322	"unexpected item type %u in sys_array at offset %u",
2323	key.type, cur);
2324	return -EUCLEAN;
2325	}
2326	chunk = (struct btrfs_chunk *)(sb->sys_chunk_array + cur);
2327	num_stripes = btrfs_stack_chunk_num_stripes(s: chunk);
2328	if (unlikely(cur + btrfs_chunk_item_size(num_stripes) > sys_array_size))
2329	goto short_read;
2330	type = btrfs_stack_chunk_type(s: chunk);
2331	if (unlikely(!(type & BTRFS_BLOCK_GROUP_SYSTEM))) {
2332	btrfs_err(fs_info,
2333	"invalid chunk type %llu in sys_array at offset %u",
2334	type, cur);
2335	return -EUCLEAN;
2336	}
2337	ret = btrfs_check_chunk_valid(fs_info, NULL, chunk, logical: key.offset,
2338	sectorsize);
2339	if (ret < 0)
2340	return ret;
2341	cur += btrfs_chunk_item_size(num_stripes);
2342	}
2343	return 0;
2344	short_read:
2345	btrfs_err(fs_info,
2346	"super block sys chunk array short read, cur=%u sys_array_size=%u",
2347	cur, sys_array_size);
2348	return -EUCLEAN;
2349	}
2350
2351	/*
2352	* Real super block validation
2353	* NOTE: super csum type and incompat features will not be checked here.
2354	*
2355	* @sb: super block to check
2356	* @mirror_num: the super block number to check its bytenr:
2357	* 0 the primary (1st) sb
2358	* 1, 2 2nd and 3rd backup copy
2359	* -1 skip bytenr check
2360	*/
2361	int btrfs_validate_super(const struct btrfs_fs_info *fs_info,
2362	const struct btrfs_super_block *sb, int mirror_num)
2363	{
2364	u64 nodesize = btrfs_super_nodesize(s: sb);
2365	u64 sectorsize = btrfs_super_sectorsize(s: sb);
2366	int ret = 0;
2367	const bool ignore_flags = btrfs_test_opt(fs_info, IGNORESUPERFLAGS);
2368
2369	if (btrfs_super_magic(s: sb) != BTRFS_MAGIC) {
2370	btrfs_err(fs_info, "no valid FS found");
2371	ret = -EINVAL;
2372	}
2373	if ((btrfs_super_flags(s: sb) & ~BTRFS_SUPER_FLAG_SUPP)) {
2374	if (!ignore_flags) {
2375	btrfs_err(fs_info,
2376	"unrecognized or unsupported super flag 0x%llx",
2377	btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);
2378	ret = -EINVAL;
2379	} else {
2380	btrfs_info(fs_info,
2381	"unrecognized or unsupported super flags: 0x%llx, ignored",
2382	btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);
2383	}
2384	}
2385	if (btrfs_super_root_level(s: sb) >= BTRFS_MAX_LEVEL) {
2386	btrfs_err(fs_info, "tree_root level too big: %d >= %d",
2387	btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
2388	ret = -EINVAL;
2389	}
2390	if (btrfs_super_chunk_root_level(s: sb) >= BTRFS_MAX_LEVEL) {
2391	btrfs_err(fs_info, "chunk_root level too big: %d >= %d",
2392	btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
2393	ret = -EINVAL;
2394	}
2395	if (btrfs_super_log_root_level(s: sb) >= BTRFS_MAX_LEVEL) {
2396	btrfs_err(fs_info, "log_root level too big: %d >= %d",
2397	btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
2398	ret = -EINVAL;
2399	}
2400
2401	/*
2402	* Check sectorsize and nodesize first, other check will need it.
2403	* Check all possible sectorsize(4K, 8K, 16K, 32K, 64K) here.
2404	*/
2405	if (!is_power_of_2(n: sectorsize) || sectorsize < BTRFS_MIN_BLOCKSIZE ||
2406	sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2407	btrfs_err(fs_info, "invalid sectorsize %llu", sectorsize);
2408	ret = -EINVAL;
2409	}
2410
2411	if (!btrfs_supported_blocksize(blocksize: sectorsize)) {
2412	btrfs_err(fs_info,
2413	"sectorsize %llu not yet supported for page size %lu",
2414	sectorsize, PAGE_SIZE);
2415	ret = -EINVAL;
2416	}
2417
2418	if (!is_power_of_2(n: nodesize) || nodesize < sectorsize ||
2419	nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2420	btrfs_err(fs_info, "invalid nodesize %llu", nodesize);
2421	ret = -EINVAL;
2422	}
2423	if (nodesize != le32_to_cpu(sb->__unused_leafsize)) {
2424	btrfs_err(fs_info, "invalid leafsize %u, should be %llu",
2425	le32_to_cpu(sb->__unused_leafsize), nodesize);
2426	ret = -EINVAL;
2427	}
2428
2429	/* Root alignment check */
2430	if (!IS_ALIGNED(btrfs_super_root(sb), sectorsize)) {
2431	btrfs_warn(fs_info, "tree_root block unaligned: %llu",
2432	btrfs_super_root(sb));
2433	ret = -EINVAL;
2434	}
2435	if (!IS_ALIGNED(btrfs_super_chunk_root(sb), sectorsize)) {
2436	btrfs_warn(fs_info, "chunk_root block unaligned: %llu",
2437	btrfs_super_chunk_root(sb));
2438	ret = -EINVAL;
2439	}
2440	if (!IS_ALIGNED(btrfs_super_log_root(sb), sectorsize)) {
2441	btrfs_warn(fs_info, "log_root block unaligned: %llu",
2442	btrfs_super_log_root(sb));
2443	ret = -EINVAL;
2444	}
2445
2446	if (!fs_info->fs_devices->temp_fsid &&
2447	memcmp(p: fs_info->fs_devices->fsid, q: sb->fsid, BTRFS_FSID_SIZE) != 0) {
2448	btrfs_err(fs_info,
2449	"superblock fsid doesn't match fsid of fs_devices: %pU != %pU",
2450	sb->fsid, fs_info->fs_devices->fsid);
2451	ret = -EINVAL;
2452	}
2453
2454	if (memcmp(p: fs_info->fs_devices->metadata_uuid, q: btrfs_sb_fsid_ptr(sb),
2455	BTRFS_FSID_SIZE) != 0) {
2456	btrfs_err(fs_info,
2457	"superblock metadata_uuid doesn't match metadata uuid of fs_devices: %pU != %pU",
2458	btrfs_sb_fsid_ptr(sb), fs_info->fs_devices->metadata_uuid);
2459	ret = -EINVAL;
2460	}
2461
2462	if (memcmp(p: fs_info->fs_devices->metadata_uuid, q: sb->dev_item.fsid,
2463	BTRFS_FSID_SIZE) != 0) {
2464	btrfs_err(fs_info,
2465	"dev_item UUID does not match metadata fsid: %pU != %pU",
2466	fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid);
2467	ret = -EINVAL;
2468	}
2469
2470	/*
2471	* Artificial requirement for block-group-tree to force newer features
2472	* (free-space-tree, no-holes) so the test matrix is smaller.
2473	*/
2474	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE) &&
2475	(!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID) ||
2476	!btrfs_fs_incompat(fs_info, NO_HOLES))) {
2477	btrfs_err(fs_info,
2478	"block-group-tree feature requires free-space-tree and no-holes");
2479	ret = -EINVAL;
2480	}
2481
2482	/*
2483	* Hint to catch really bogus numbers, bitflips or so, more exact checks are
2484	* done later
2485	*/
2486	if (btrfs_super_bytes_used(s: sb) < 6 * btrfs_super_nodesize(s: sb)) {
2487	btrfs_err(fs_info, "bytes_used is too small %llu",
2488	btrfs_super_bytes_used(sb));
2489	ret = -EINVAL;
2490	}
2491	if (!is_power_of_2(n: btrfs_super_stripesize(s: sb))) {
2492	btrfs_err(fs_info, "invalid stripesize %u",
2493	btrfs_super_stripesize(sb));
2494	ret = -EINVAL;
2495	}
2496	if (btrfs_super_num_devices(s: sb) > (1UL << 31))
2497	btrfs_warn(fs_info, "suspicious number of devices: %llu",
2498	btrfs_super_num_devices(sb));
2499	if (btrfs_super_num_devices(s: sb) == 0) {
2500	btrfs_err(fs_info, "number of devices is 0");
2501	ret = -EINVAL;
2502	}
2503
2504	if (mirror_num >= 0 &&
2505	btrfs_super_bytenr(s: sb) != btrfs_sb_offset(mirror: mirror_num)) {
2506	btrfs_err(fs_info, "super offset mismatch %llu != %u",
2507	btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET);
2508	ret = -EINVAL;
2509	}
2510
2511	if (ret)
2512	return ret;
2513
2514	ret = validate_sys_chunk_array(fs_info, sb);
2515
2516	/*
2517	* Obvious sys_chunk_array corruptions, it must hold at least one key
2518	* and one chunk
2519	*/
2520	if (btrfs_super_sys_array_size(s: sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
2521	btrfs_err(fs_info, "system chunk array too big %u > %u",
2522	btrfs_super_sys_array_size(sb),
2523	BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
2524	ret = -EINVAL;
2525	}
2526	if (btrfs_super_sys_array_size(s: sb) < sizeof(struct btrfs_disk_key)
2527	+ sizeof(struct btrfs_chunk)) {
2528	btrfs_err(fs_info, "system chunk array too small %u < %zu",
2529	btrfs_super_sys_array_size(sb),
2530	sizeof(struct btrfs_disk_key)
2531	+ sizeof(struct btrfs_chunk));
2532	ret = -EINVAL;
2533	}
2534
2535	/*
2536	* The generation is a global counter, we'll trust it more than the others
2537	* but it's still possible that it's the one that's wrong.
2538	*/
2539	if (btrfs_super_generation(s: sb) < btrfs_super_chunk_root_generation(s: sb))
2540	btrfs_warn(fs_info,
2541	"suspicious: generation < chunk_root_generation: %llu < %llu",
2542	btrfs_super_generation(sb),
2543	btrfs_super_chunk_root_generation(sb));
2544	if (btrfs_super_generation(s: sb) < btrfs_super_cache_generation(s: sb)
2545	&& btrfs_super_cache_generation(s: sb) != (u64)-1)
2546	btrfs_warn(fs_info,
2547	"suspicious: generation < cache_generation: %llu < %llu",
2548	btrfs_super_generation(sb),
2549	btrfs_super_cache_generation(sb));
2550
2551	return ret;
2552	}
2553
2554	/*
2555	* Validation of super block at mount time.
2556	* Some checks already done early at mount time, like csum type and incompat
2557	* flags will be skipped.
2558	*/
2559	static int btrfs_validate_mount_super(struct btrfs_fs_info *fs_info)
2560	{
2561	return btrfs_validate_super(fs_info, sb: fs_info->super_copy, mirror_num: 0);
2562	}
2563
2564	/*
2565	* Validation of super block at write time.
2566	* Some checks like bytenr check will be skipped as their values will be
2567	* overwritten soon.
2568	* Extra checks like csum type and incompat flags will be done here.
2569	*/
2570	static int btrfs_validate_write_super(struct btrfs_fs_info *fs_info,
2571	struct btrfs_super_block *sb)
2572	{
2573	int ret;
2574
2575	ret = btrfs_validate_super(fs_info, sb, mirror_num: -1);
2576	if (ret < 0)
2577	goto out;
2578	if (unlikely(!btrfs_supported_super_csum(btrfs_super_csum_type(sb)))) {
2579	ret = -EUCLEAN;
2580	btrfs_err(fs_info, "invalid csum type, has %u want %u",
2581	btrfs_super_csum_type(sb), BTRFS_CSUM_TYPE_CRC32);
2582	goto out;
2583	}
2584	if (unlikely(btrfs_super_incompat_flags(sb) & ~BTRFS_FEATURE_INCOMPAT_SUPP)) {
2585	ret = -EUCLEAN;
2586	btrfs_err(fs_info,
2587	"invalid incompat flags, has 0x%llx valid mask 0x%llx",
2588	btrfs_super_incompat_flags(sb),
2589	(unsigned long long)BTRFS_FEATURE_INCOMPAT_SUPP);
2590	goto out;
2591	}
2592	out:
2593	if (ret < 0)
2594	btrfs_err(fs_info,
2595	"super block corruption detected before writing it to disk");
2596	return ret;
2597	}
2598
2599	static int load_super_root(struct btrfs_root *root, u64 bytenr, u64 gen, int level)
2600	{
2601	struct btrfs_tree_parent_check check = {
2602	.level = level,
2603	.transid = gen,
2604	.owner_root = btrfs_root_id(root)
2605	};
2606	int ret = 0;
2607
2608	root->node = read_tree_block(fs_info: root->fs_info, bytenr, check: &check);
2609	if (IS_ERR(ptr: root->node)) {
2610	ret = PTR_ERR(ptr: root->node);
2611	root->node = NULL;
2612	return ret;
2613	}
2614	if (unlikely(!extent_buffer_uptodate(root->node))) {
2615	free_extent_buffer(eb: root->node);
2616	root->node = NULL;
2617	return -EIO;
2618	}
2619
2620	btrfs_set_root_node(item: &root->root_item, node: root->node);
2621	root->commit_root = btrfs_root_node(root);
2622	btrfs_set_root_refs(s: &root->root_item, val: 1);
2623	return ret;
2624	}
2625
2626	static int load_important_roots(struct btrfs_fs_info *fs_info)
2627	{
2628	struct btrfs_super_block *sb = fs_info->super_copy;
2629	u64 gen, bytenr;
2630	int level, ret;
2631
2632	bytenr = btrfs_super_root(s: sb);
2633	gen = btrfs_super_generation(s: sb);
2634	level = btrfs_super_root_level(s: sb);
2635	ret = load_super_root(root: fs_info->tree_root, bytenr, gen, level);
2636	if (ret) {
2637	btrfs_warn(fs_info, "couldn't read tree root");
2638	return ret;
2639	}
2640	return 0;
2641	}
2642
2643	static int __cold init_tree_roots(struct btrfs_fs_info *fs_info)
2644	{
2645	int backup_index = find_newest_super_backup(info: fs_info);
2646	struct btrfs_super_block *sb = fs_info->super_copy;
2647	struct btrfs_root *tree_root = fs_info->tree_root;
2648	bool handle_error = false;
2649	int ret = 0;
2650	int i;
2651
2652	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
2653	if (handle_error) {
2654	if (!IS_ERR(ptr: tree_root->node))
2655	free_extent_buffer(eb: tree_root->node);
2656	tree_root->node = NULL;
2657
2658	if (!btrfs_test_opt(fs_info, USEBACKUPROOT))
2659	break;
2660
2661	free_root_pointers(info: fs_info, free_chunk_root: 0);
2662
2663	/*
2664	* Don't use the log in recovery mode, it won't be
2665	* valid
2666	*/
2667	btrfs_set_super_log_root(s: sb, val: 0);
2668
2669	btrfs_warn(fs_info, "try to load backup roots slot %d", i);
2670	ret = read_backup_root(fs_info, priority: i);
2671	backup_index = ret;
2672	if (ret < 0)
2673	return ret;
2674	}
2675
2676	ret = load_important_roots(fs_info);
2677	if (ret) {
2678	handle_error = true;
2679	continue;
2680	}
2681
2682	/*
2683	* No need to hold btrfs_root::objectid_mutex since the fs
2684	* hasn't been fully initialised and we are the only user
2685	*/
2686	ret = btrfs_init_root_free_objectid(root: tree_root);
2687	if (ret < 0) {
2688	handle_error = true;
2689	continue;
2690	}
2691
2692	ASSERT(tree_root->free_objectid <= BTRFS_LAST_FREE_OBJECTID);
2693
2694	ret = btrfs_read_roots(fs_info);
2695	if (ret < 0) {
2696	handle_error = true;
2697	continue;
2698	}
2699
2700	/* All successful */
2701	fs_info->generation = btrfs_header_generation(eb: tree_root->node);
2702	btrfs_set_last_trans_committed(fs_info, gen: fs_info->generation);
2703	fs_info->last_reloc_trans = 0;
2704
2705	/* Always begin writing backup roots after the one being used */
2706	if (backup_index < 0) {
2707	fs_info->backup_root_index = 0;
2708	} else {
2709	fs_info->backup_root_index = backup_index + 1;
2710	fs_info->backup_root_index %= BTRFS_NUM_BACKUP_ROOTS;
2711	}
2712	break;
2713	}
2714
2715	return ret;
2716	}
2717
2718	/*
2719	* Lockdep gets confused between our buffer_tree which requires IRQ locking because
2720	* we modify marks in the IRQ context, and our delayed inode xarray which doesn't
2721	* have these requirements. Use a class key so lockdep doesn't get them mixed up.
2722	*/
2723	static struct lock_class_key buffer_xa_class;
2724
2725	void btrfs_init_fs_info(struct btrfs_fs_info *fs_info)
2726	{
2727	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
2728
2729	/* Use the same flags as mapping->i_pages. */
2730	xa_init_flags(xa: &fs_info->buffer_tree, XA_FLAGS_LOCK_IRQ | XA_FLAGS_ACCOUNT);
2731	lockdep_set_class(&fs_info->buffer_tree.xa_lock, &buffer_xa_class);
2732
2733	INIT_LIST_HEAD(list: &fs_info->trans_list);
2734	INIT_LIST_HEAD(list: &fs_info->dead_roots);
2735	INIT_LIST_HEAD(list: &fs_info->delayed_iputs);
2736	INIT_LIST_HEAD(list: &fs_info->delalloc_roots);
2737	INIT_LIST_HEAD(list: &fs_info->caching_block_groups);
2738	spin_lock_init(&fs_info->delalloc_root_lock);
2739	spin_lock_init(&fs_info->trans_lock);
2740	spin_lock_init(&fs_info->fs_roots_radix_lock);
2741	spin_lock_init(&fs_info->delayed_iput_lock);
2742	spin_lock_init(&fs_info->defrag_inodes_lock);
2743	spin_lock_init(&fs_info->super_lock);
2744	spin_lock_init(&fs_info->unused_bgs_lock);
2745	spin_lock_init(&fs_info->treelog_bg_lock);
2746	spin_lock_init(&fs_info->zone_active_bgs_lock);
2747	spin_lock_init(&fs_info->relocation_bg_lock);
2748	rwlock_init(&fs_info->tree_mod_log_lock);
2749	rwlock_init(&fs_info->global_root_lock);
2750	mutex_init(&fs_info->unused_bg_unpin_mutex);
2751	mutex_init(&fs_info->reclaim_bgs_lock);
2752	mutex_init(&fs_info->reloc_mutex);
2753	mutex_init(&fs_info->delalloc_root_mutex);
2754	mutex_init(&fs_info->zoned_meta_io_lock);
2755	mutex_init(&fs_info->zoned_data_reloc_io_lock);
2756	seqlock_init(&fs_info->profiles_lock);
2757
2758	btrfs_lockdep_init_map(fs_info, btrfs_trans_num_writers);
2759	btrfs_lockdep_init_map(fs_info, btrfs_trans_num_extwriters);
2760	btrfs_lockdep_init_map(fs_info, btrfs_trans_pending_ordered);
2761	btrfs_lockdep_init_map(fs_info, btrfs_ordered_extent);
2762	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_commit_prep,
2763	BTRFS_LOCKDEP_TRANS_COMMIT_PREP);
2764	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_unblocked,
2765	BTRFS_LOCKDEP_TRANS_UNBLOCKED);
2766	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_super_committed,
2767	BTRFS_LOCKDEP_TRANS_SUPER_COMMITTED);
2768	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_completed,
2769	BTRFS_LOCKDEP_TRANS_COMPLETED);
2770
2771	INIT_LIST_HEAD(list: &fs_info->dirty_cowonly_roots);
2772	INIT_LIST_HEAD(list: &fs_info->space_info);
2773	INIT_LIST_HEAD(list: &fs_info->tree_mod_seq_list);
2774	INIT_LIST_HEAD(list: &fs_info->unused_bgs);
2775	INIT_LIST_HEAD(list: &fs_info->reclaim_bgs);
2776	INIT_LIST_HEAD(list: &fs_info->zone_active_bgs);
2777	#ifdef CONFIG_BTRFS_DEBUG
2778	INIT_LIST_HEAD(list: &fs_info->allocated_roots);
2779	INIT_LIST_HEAD(list: &fs_info->allocated_ebs);
2780	spin_lock_init(&fs_info->eb_leak_lock);
2781	#endif
2782	fs_info->mapping_tree = RB_ROOT_CACHED;
2783	rwlock_init(&fs_info->mapping_tree_lock);
2784	btrfs_init_block_rsv(rsv: &fs_info->global_block_rsv,
2785	type: BTRFS_BLOCK_RSV_GLOBAL);
2786	btrfs_init_block_rsv(rsv: &fs_info->trans_block_rsv, type: BTRFS_BLOCK_RSV_TRANS);
2787	btrfs_init_block_rsv(rsv: &fs_info->chunk_block_rsv, type: BTRFS_BLOCK_RSV_CHUNK);
2788	btrfs_init_block_rsv(rsv: &fs_info->treelog_rsv, type: BTRFS_BLOCK_RSV_TREELOG);
2789	btrfs_init_block_rsv(rsv: &fs_info->empty_block_rsv, type: BTRFS_BLOCK_RSV_EMPTY);
2790	btrfs_init_block_rsv(rsv: &fs_info->delayed_block_rsv,
2791	type: BTRFS_BLOCK_RSV_DELOPS);
2792	btrfs_init_block_rsv(rsv: &fs_info->delayed_refs_rsv,
2793	type: BTRFS_BLOCK_RSV_DELREFS);
2794
2795	atomic_set(v: &fs_info->async_delalloc_pages, i: 0);
2796	atomic_set(v: &fs_info->defrag_running, i: 0);
2797	atomic_set(v: &fs_info->nr_delayed_iputs, i: 0);
2798	atomic64_set(v: &fs_info->tree_mod_seq, i: 0);
2799	fs_info->global_root_tree = RB_ROOT;
2800	fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE;
2801	fs_info->metadata_ratio = 0;
2802	fs_info->defrag_inodes = RB_ROOT;
2803	atomic64_set(v: &fs_info->free_chunk_space, i: 0);
2804	fs_info->tree_mod_log = RB_ROOT;
2805	fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
2806	btrfs_init_ref_verify(fs_info);
2807
2808	fs_info->thread_pool_size = min_t(unsigned long,
2809	num_online_cpus() + 2, 8);
2810
2811	INIT_LIST_HEAD(list: &fs_info->ordered_roots);
2812	spin_lock_init(&fs_info->ordered_root_lock);
2813
2814	btrfs_init_scrub(fs_info);
2815	btrfs_init_balance(fs_info);
2816	btrfs_init_async_reclaim_work(fs_info);
2817	btrfs_init_extent_map_shrinker_work(fs_info);
2818
2819	rwlock_init(&fs_info->block_group_cache_lock);
2820	fs_info->block_group_cache_tree = RB_ROOT_CACHED;
2821
2822	btrfs_extent_io_tree_init(fs_info, tree: &fs_info->excluded_extents,
2823	owner: IO_TREE_FS_EXCLUDED_EXTENTS);
2824
2825	mutex_init(&fs_info->ordered_operations_mutex);
2826	mutex_init(&fs_info->tree_log_mutex);
2827	mutex_init(&fs_info->chunk_mutex);
2828	mutex_init(&fs_info->transaction_kthread_mutex);
2829	mutex_init(&fs_info->cleaner_mutex);
2830	mutex_init(&fs_info->ro_block_group_mutex);
2831	init_rwsem(&fs_info->commit_root_sem);
2832	init_rwsem(&fs_info->cleanup_work_sem);
2833	init_rwsem(&fs_info->subvol_sem);
2834	sema_init(sem: &fs_info->uuid_tree_rescan_sem, val: 1);
2835
2836	btrfs_init_dev_replace_locks(fs_info);
2837	btrfs_init_qgroup(fs_info);
2838	btrfs_discard_init(fs_info);
2839
2840	btrfs_init_free_cluster(cluster: &fs_info->meta_alloc_cluster);
2841	btrfs_init_free_cluster(cluster: &fs_info->data_alloc_cluster);
2842
2843	init_waitqueue_head(&fs_info->transaction_throttle);
2844	init_waitqueue_head(&fs_info->transaction_wait);
2845	init_waitqueue_head(&fs_info->transaction_blocked_wait);
2846	init_waitqueue_head(&fs_info->async_submit_wait);
2847	init_waitqueue_head(&fs_info->delayed_iputs_wait);
2848
2849	/* Usable values until the real ones are cached from the superblock */
2850	fs_info->nodesize = 4096;
2851	fs_info->sectorsize = 4096;
2852	fs_info->sectorsize_bits = ilog2(4096);
2853	fs_info->stripesize = 4096;
2854
2855	/* Default compress algorithm when user does -o compress */
2856	fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
2857
2858	fs_info->max_extent_size = BTRFS_MAX_EXTENT_SIZE;
2859
2860	spin_lock_init(&fs_info->swapfile_pins_lock);
2861	fs_info->swapfile_pins = RB_ROOT;
2862
2863	fs_info->bg_reclaim_threshold = BTRFS_DEFAULT_RECLAIM_THRESH;
2864	INIT_WORK(&fs_info->reclaim_bgs_work, btrfs_reclaim_bgs_work);
2865	}
2866
2867	static int init_mount_fs_info(struct btrfs_fs_info *fs_info, struct super_block *sb)
2868	{
2869	int ret;
2870
2871	fs_info->sb = sb;
2872	/* Temporary fixed values for block size until we read the superblock. */
2873	sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE;
2874	sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE);
2875
2876	ret = percpu_counter_init(&fs_info->ordered_bytes, 0, GFP_KERNEL);
2877	if (ret)
2878	return ret;
2879
2880	ret = percpu_counter_init(&fs_info->evictable_extent_maps, 0, GFP_KERNEL);
2881	if (ret)
2882	return ret;
2883
2884	ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0, GFP_KERNEL);
2885	if (ret)
2886	return ret;
2887
2888	ret = percpu_counter_init(&fs_info->stats_read_blocks, 0, GFP_KERNEL);
2889	if (ret)
2890	return ret;
2891
2892	fs_info->dirty_metadata_batch = PAGE_SIZE *
2893	(1 + ilog2(nr_cpu_ids));
2894
2895	ret = percpu_counter_init(&fs_info->delalloc_bytes, 0, GFP_KERNEL);
2896	if (ret)
2897	return ret;
2898
2899	ret = percpu_counter_init(&fs_info->dev_replace.bio_counter, 0,
2900	GFP_KERNEL);
2901	if (ret)
2902	return ret;
2903
2904	fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
2905	GFP_KERNEL);
2906	if (!fs_info->delayed_root)
2907	return -ENOMEM;
2908	btrfs_init_delayed_root(delayed_root: fs_info->delayed_root);
2909
2910	if (sb_rdonly(sb))
2911	set_bit(nr: BTRFS_FS_STATE_RO, addr: &fs_info->fs_state);
2912	if (btrfs_test_opt(fs_info, IGNOREMETACSUMS))
2913	set_bit(nr: BTRFS_FS_STATE_SKIP_META_CSUMS, addr: &fs_info->fs_state);
2914
2915	return btrfs_alloc_stripe_hash_table(info: fs_info);
2916	}
2917
2918	static int btrfs_uuid_rescan_kthread(void *data)
2919	{
2920	struct btrfs_fs_info *fs_info = data;
2921	int ret;
2922
2923	/*
2924	* 1st step is to iterate through the existing UUID tree and
2925	* to delete all entries that contain outdated data.
2926	* 2nd step is to add all missing entries to the UUID tree.
2927	*/
2928	ret = btrfs_uuid_tree_iterate(fs_info);
2929	if (ret < 0) {
2930	if (ret != -EINTR)
2931	btrfs_warn(fs_info, "iterating uuid_tree failed %d",
2932	ret);
2933	up(sem: &fs_info->uuid_tree_rescan_sem);
2934	return ret;
2935	}
2936	return btrfs_uuid_scan_kthread(data);
2937	}
2938
2939	static int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
2940	{
2941	struct task_struct *task;
2942
2943	down(sem: &fs_info->uuid_tree_rescan_sem);
2944	task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
2945	if (IS_ERR(ptr: task)) {
2946	/* fs_info->update_uuid_tree_gen remains 0 in all error case */
2947	btrfs_warn(fs_info, "failed to start uuid_rescan task");
2948	up(sem: &fs_info->uuid_tree_rescan_sem);
2949	return PTR_ERR(ptr: task);
2950	}
2951
2952	return 0;
2953	}
2954
2955	static int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
2956	{
2957	u64 root_objectid = 0;
2958	struct btrfs_root *gang[8];
2959	int ret = 0;
2960
2961	while (1) {
2962	unsigned int found;
2963
2964	spin_lock(lock: &fs_info->fs_roots_radix_lock);
2965	found = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2966	results: (void **)gang, first_index: root_objectid,
2967	ARRAY_SIZE(gang));
2968	if (!found) {
2969	spin_unlock(lock: &fs_info->fs_roots_radix_lock);
2970	break;
2971	}
2972	root_objectid = btrfs_root_id(root: gang[found - 1]) + 1;
2973
2974	for (int i = 0; i < found; i++) {
2975	/* Avoid to grab roots in dead_roots. */
2976	if (btrfs_root_refs(s: &gang[i]->root_item) == 0) {
2977	gang[i] = NULL;
2978	continue;
2979	}
2980	/* Grab all the search result for later use. */
2981	gang[i] = btrfs_grab_root(root: gang[i]);
2982	}
2983	spin_unlock(lock: &fs_info->fs_roots_radix_lock);
2984
2985	for (int i = 0; i < found; i++) {
2986	if (!gang[i])
2987	continue;
2988	root_objectid = btrfs_root_id(root: gang[i]);
2989	/*
2990	* Continue to release the remaining roots after the first
2991	* error without cleanup and preserve the first error
2992	* for the return.
2993	*/
2994	if (!ret)
2995	ret = btrfs_orphan_cleanup(root: gang[i]);
2996	btrfs_put_root(root: gang[i]);
2997	}
2998	if (ret)
2999	break;
3000
3001	root_objectid++;
3002	}
3003	return ret;
3004	}
3005
3006	/*
3007	* Mounting logic specific to read-write file systems. Shared by open_ctree
3008	* and btrfs_remount when remounting from read-only to read-write.
3009	*/
3010	int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info)
3011	{
3012	int ret;
3013	const bool cache_opt = btrfs_test_opt(fs_info, SPACE_CACHE);
3014	bool rebuild_free_space_tree = false;
3015
3016	if (btrfs_test_opt(fs_info, CLEAR_CACHE) &&
3017	btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3018	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
3019	btrfs_warn(fs_info,
3020	"'clear_cache' option is ignored with extent tree v2");
3021	else
3022	rebuild_free_space_tree = true;
3023	} else if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
3024	!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID)) {
3025	btrfs_warn(fs_info, "free space tree is invalid");
3026	rebuild_free_space_tree = true;
3027	}
3028
3029	if (rebuild_free_space_tree) {
3030	btrfs_info(fs_info, "rebuilding free space tree");
3031	ret = btrfs_rebuild_free_space_tree(fs_info);
3032	if (ret) {
3033	btrfs_warn(fs_info,
3034	"failed to rebuild free space tree: %d", ret);
3035	goto out;
3036	}
3037	}
3038
3039	if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
3040	!btrfs_test_opt(fs_info, FREE_SPACE_TREE)) {
3041	btrfs_info(fs_info, "disabling free space tree");
3042	ret = btrfs_delete_free_space_tree(fs_info);
3043	if (ret) {
3044	btrfs_warn(fs_info,
3045	"failed to disable free space tree: %d", ret);
3046	goto out;
3047	}
3048	}
3049
3050	/*
3051	* btrfs_find_orphan_roots() is responsible for finding all the dead
3052	* roots (with 0 refs), flag them with BTRFS_ROOT_DEAD_TREE and load
3053	* them into the fs_info->fs_roots_radix tree. This must be done before
3054	* calling btrfs_orphan_cleanup() on the tree root. If we don't do it
3055	* first, then btrfs_orphan_cleanup() will delete a dead root's orphan
3056	* item before the root's tree is deleted - this means that if we unmount
3057	* or crash before the deletion completes, on the next mount we will not
3058	* delete what remains of the tree because the orphan item does not
3059	* exists anymore, which is what tells us we have a pending deletion.
3060	*/
3061	ret = btrfs_find_orphan_roots(fs_info);
3062	if (ret)
3063	goto out;
3064
3065	ret = btrfs_cleanup_fs_roots(fs_info);
3066	if (ret)
3067	goto out;
3068
3069	down_read(sem: &fs_info->cleanup_work_sem);
3070	if ((ret = btrfs_orphan_cleanup(root: fs_info->fs_root)) ||
3071	(ret = btrfs_orphan_cleanup(root: fs_info->tree_root))) {
3072	up_read(sem: &fs_info->cleanup_work_sem);
3073	goto out;
3074	}
3075	up_read(sem: &fs_info->cleanup_work_sem);
3076
3077	mutex_lock(&fs_info->cleaner_mutex);
3078	ret = btrfs_recover_relocation(fs_info);
3079	mutex_unlock(lock: &fs_info->cleaner_mutex);
3080	if (ret < 0) {
3081	btrfs_warn(fs_info, "failed to recover relocation: %d", ret);
3082	goto out;
3083	}
3084
3085	if (btrfs_test_opt(fs_info, FREE_SPACE_TREE) &&
3086	!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3087	btrfs_info(fs_info, "creating free space tree");
3088	ret = btrfs_create_free_space_tree(fs_info);
3089	if (ret) {
3090	btrfs_warn(fs_info,
3091	"failed to create free space tree: %d", ret);
3092	goto out;
3093	}
3094	}
3095
3096	if (cache_opt != btrfs_free_space_cache_v1_active(fs_info)) {
3097	ret = btrfs_set_free_space_cache_v1_active(fs_info, active: cache_opt);
3098	if (ret)
3099	goto out;
3100	}
3101
3102	ret = btrfs_resume_balance_async(fs_info);
3103	if (ret)
3104	goto out;
3105
3106	ret = btrfs_resume_dev_replace_async(fs_info);
3107	if (ret) {
3108	btrfs_warn(fs_info, "failed to resume dev_replace");
3109	goto out;
3110	}
3111
3112	btrfs_qgroup_rescan_resume(fs_info);
3113
3114	if (!fs_info->uuid_root) {
3115	btrfs_info(fs_info, "creating UUID tree");
3116	ret = btrfs_create_uuid_tree(fs_info);
3117	if (ret) {
3118	btrfs_warn(fs_info,
3119	"failed to create the UUID tree %d", ret);
3120	goto out;
3121	}
3122	}
3123
3124	out:
3125	return ret;
3126	}
3127
3128	/*
3129	* Do various sanity and dependency checks of different features.
3130	*
3131	* @is_rw_mount: If the mount is read-write.
3132	*
3133	* This is the place for less strict checks (like for subpage or artificial
3134	* feature dependencies).
3135	*
3136	* For strict checks or possible corruption detection, see
3137	* btrfs_validate_super().
3138	*
3139	* This should be called after btrfs_parse_options(), as some mount options
3140	* (space cache related) can modify on-disk format like free space tree and
3141	* screw up certain feature dependencies.
3142	*/
3143	int btrfs_check_features(struct btrfs_fs_info *fs_info, bool is_rw_mount)
3144	{
3145	struct btrfs_super_block *disk_super = fs_info->super_copy;
3146	u64 incompat = btrfs_super_incompat_flags(s: disk_super);
3147	const u64 compat_ro = btrfs_super_compat_ro_flags(s: disk_super);
3148	const u64 compat_ro_unsupp = (compat_ro & ~BTRFS_FEATURE_COMPAT_RO_SUPP);
3149
3150	if (incompat & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
3151	btrfs_err(fs_info,
3152	"cannot mount because of unknown incompat features (0x%llx)",
3153	incompat);
3154	return -EINVAL;
3155	}
3156
3157	/* Runtime limitation for mixed block groups. */
3158	if ((incompat & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
3159	(fs_info->sectorsize != fs_info->nodesize)) {
3160	btrfs_err(fs_info,
3161	"unequal nodesize/sectorsize (%u != %u) are not allowed for mixed block groups",
3162	fs_info->nodesize, fs_info->sectorsize);
3163	return -EINVAL;
3164	}
3165
3166	/* Mixed backref is an always-enabled feature. */
3167	incompat |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
3168
3169	/* Set compression related flags just in case. */
3170	if (fs_info->compress_type == BTRFS_COMPRESS_LZO)
3171	incompat |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
3172	else if (fs_info->compress_type == BTRFS_COMPRESS_ZSTD)
3173	incompat |= BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD;
3174
3175	/*
3176	* An ancient flag, which should really be marked deprecated.
3177	* Such runtime limitation doesn't really need a incompat flag.
3178	*/
3179	if (btrfs_super_nodesize(s: disk_super) > PAGE_SIZE)
3180	incompat |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
3181
3182	if (compat_ro_unsupp && is_rw_mount) {
3183	btrfs_err(fs_info,
3184	"cannot mount read-write because of unknown compat_ro features (0x%llx)",
3185	compat_ro);
3186	return -EINVAL;
3187	}
3188
3189	/*
3190	* We have unsupported RO compat features, although RO mounted, we
3191	* should not cause any metadata writes, including log replay.
3192	* Or we could screw up whatever the new feature requires.
3193	*/
3194	if (compat_ro_unsupp && btrfs_super_log_root(s: disk_super) &&
3195	!btrfs_test_opt(fs_info, NOLOGREPLAY)) {
3196	btrfs_err(fs_info,
3197	"cannot replay dirty log with unsupported compat_ro features (0x%llx), try rescue=nologreplay",
3198	compat_ro);
3199	return -EINVAL;
3200	}
3201
3202	/*
3203	* Artificial limitations for block group tree, to force
3204	* block-group-tree to rely on no-holes and free-space-tree.
3205	*/
3206	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE) &&
3207	(!btrfs_fs_incompat(fs_info, NO_HOLES) ||
3208	!btrfs_test_opt(fs_info, FREE_SPACE_TREE))) {
3209	btrfs_err(fs_info,
3210	"block-group-tree feature requires no-holes and free-space-tree features");
3211	return -EINVAL;
3212	}
3213
3214	/*
3215	* Subpage/bs > ps runtime limitation on v1 cache.
3216	*
3217	* V1 space cache still has some hard coded PAGE_SIZE usage, while
3218	* we're already defaulting to v2 cache, no need to bother v1 as it's
3219	* going to be deprecated anyway.
3220	*/
3221	if (fs_info->sectorsize != PAGE_SIZE && btrfs_test_opt(fs_info, SPACE_CACHE)) {
3222	btrfs_warn(fs_info,
3223	"v1 space cache is not supported for page size %lu with sectorsize %u",
3224	PAGE_SIZE, fs_info->sectorsize);
3225	return -EINVAL;
3226	}
3227
3228	/* This can be called by remount, we need to protect the super block. */
3229	spin_lock(lock: &fs_info->super_lock);
3230	btrfs_set_super_incompat_flags(s: disk_super, val: incompat);
3231	spin_unlock(lock: &fs_info->super_lock);
3232
3233	return 0;
3234	}
3235
3236	static bool fs_is_full_ro(const struct btrfs_fs_info *fs_info)
3237	{
3238	if (!sb_rdonly(sb: fs_info->sb))
3239	return false;
3240	if (unlikely(fs_info->mount_opt & BTRFS_MOUNT_FULL_RO_MASK))
3241	return true;
3242	return false;
3243	}
3244
3245	int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_devices)
3246	{
3247	u32 sectorsize;
3248	u32 nodesize;
3249	u32 stripesize;
3250	u64 generation;
3251	u16 csum_type;
3252	struct btrfs_super_block *disk_super;
3253	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
3254	struct btrfs_root *tree_root;
3255	struct btrfs_root *chunk_root;
3256	int ret;
3257	int level;
3258
3259	ret = init_mount_fs_info(fs_info, sb);
3260	if (ret)
3261	goto fail;
3262
3263	/* These need to be init'ed before we start creating inodes and such. */
3264	tree_root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID,
3265	GFP_KERNEL);
3266	fs_info->tree_root = tree_root;
3267	chunk_root = btrfs_alloc_root(fs_info, BTRFS_CHUNK_TREE_OBJECTID,
3268	GFP_KERNEL);
3269	fs_info->chunk_root = chunk_root;
3270	if (!tree_root || !chunk_root) {
3271	ret = -ENOMEM;
3272	goto fail;
3273	}
3274
3275	ret = btrfs_init_btree_inode(sb);
3276	if (ret)
3277	goto fail;
3278
3279	invalidate_bdev(bdev: fs_devices->latest_dev->bdev);
3280
3281	/*
3282	* Read super block and check the signature bytes only
3283	*/
3284	disk_super = btrfs_read_disk_super(bdev: fs_devices->latest_dev->bdev, copy_num: 0, drop_cache: false);
3285	if (IS_ERR(ptr: disk_super)) {
3286	ret = PTR_ERR(ptr: disk_super);
3287	goto fail_alloc;
3288	}
3289
3290	btrfs_info(fs_info, "first mount of filesystem %pU", disk_super->fsid);
3291	/*
3292	* Verify the type first, if that or the checksum value are
3293	* corrupted, we'll find out
3294	*/
3295	csum_type = btrfs_super_csum_type(s: disk_super);
3296	if (!btrfs_supported_super_csum(csum_type)) {
3297	btrfs_err(fs_info, "unsupported checksum algorithm: %u",
3298	csum_type);
3299	ret = -EINVAL;
3300	btrfs_release_disk_super(super: disk_super);
3301	goto fail_alloc;
3302	}
3303
3304	fs_info->csum_size = btrfs_super_csum_size(s: disk_super);
3305
3306	ret = btrfs_init_csum_hash(fs_info, csum_type);
3307	if (ret) {
3308	btrfs_release_disk_super(super: disk_super);
3309	goto fail_alloc;
3310	}
3311
3312	/*
3313	* We want to check superblock checksum, the type is stored inside.
3314	* Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k).
3315	*/
3316	if (btrfs_check_super_csum(fs_info, disk_sb: disk_super)) {
3317	btrfs_err(fs_info, "superblock checksum mismatch");
3318	ret = -EINVAL;
3319	btrfs_release_disk_super(super: disk_super);
3320	goto fail_alloc;
3321	}
3322
3323	/*
3324	* super_copy is zeroed at allocation time and we never touch the
3325	* following bytes up to INFO_SIZE, the checksum is calculated from
3326	* the whole block of INFO_SIZE
3327	*/
3328	memcpy(fs_info->super_copy, disk_super, sizeof(*fs_info->super_copy));
3329	btrfs_release_disk_super(super: disk_super);
3330
3331	disk_super = fs_info->super_copy;
3332
3333	memcpy(fs_info->super_for_commit, fs_info->super_copy,
3334	sizeof(*fs_info->super_for_commit));
3335
3336	ret = btrfs_validate_mount_super(fs_info);
3337	if (ret) {
3338	btrfs_err(fs_info, "superblock contains fatal errors");
3339	ret = -EINVAL;
3340	goto fail_alloc;
3341	}
3342
3343	if (!btrfs_super_root(s: disk_super)) {
3344	btrfs_err(fs_info, "invalid superblock tree root bytenr");
3345	ret = -EINVAL;
3346	goto fail_alloc;
3347	}
3348
3349	/* check FS state, whether FS is broken. */
3350	if (btrfs_super_flags(s: disk_super) & BTRFS_SUPER_FLAG_ERROR)
3351	WRITE_ONCE(fs_info->fs_error, -EUCLEAN);
3352
3353	/* If the fs has any rescue options, no transaction is allowed. */
3354	if (fs_is_full_ro(fs_info))
3355	WRITE_ONCE(fs_info->fs_error, -EROFS);
3356
3357	/* Set up fs_info before parsing mount options */
3358	nodesize = btrfs_super_nodesize(s: disk_super);
3359	sectorsize = btrfs_super_sectorsize(s: disk_super);
3360	stripesize = sectorsize;
3361	fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids));
3362	fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
3363
3364	fs_info->nodesize = nodesize;
3365	fs_info->nodesize_bits = ilog2(nodesize);
3366	fs_info->sectorsize = sectorsize;
3367	fs_info->sectorsize_bits = ilog2(sectorsize);
3368	fs_info->block_min_order = ilog2(round_up(sectorsize, PAGE_SIZE) >> PAGE_SHIFT);
3369	fs_info->block_max_order = ilog2((BITS_PER_LONG << fs_info->sectorsize_bits) >> PAGE_SHIFT);
3370	fs_info->csums_per_leaf = BTRFS_MAX_ITEM_SIZE(info: fs_info) / fs_info->csum_size;
3371	fs_info->stripesize = stripesize;
3372	fs_info->fs_devices->fs_info = fs_info;
3373
3374	if (fs_info->sectorsize > PAGE_SIZE)
3375	btrfs_warn(fs_info,
3376	"support for block size %u with page size %lu is experimental, some features may be missing",
3377	fs_info->sectorsize, PAGE_SIZE);
3378	/*
3379	* Handle the space caching options appropriately now that we have the
3380	* super block loaded and validated.
3381	*/
3382	btrfs_set_free_space_cache_settings(fs_info);
3383
3384	if (!btrfs_check_options(info: fs_info, mount_opt: &fs_info->mount_opt, flags: sb->s_flags)) {
3385	ret = -EINVAL;
3386	goto fail_alloc;
3387	}
3388
3389	ret = btrfs_check_features(fs_info, is_rw_mount: !sb_rdonly(sb));
3390	if (ret < 0)
3391	goto fail_alloc;
3392
3393	/*
3394	* At this point our mount options are validated, if we set ->max_inline
3395	* to something non-standard make sure we truncate it to sectorsize.
3396	*/
3397	fs_info->max_inline = min_t(u64, fs_info->max_inline, fs_info->sectorsize);
3398
3399	ret = btrfs_alloc_compress_wsm(fs_info);
3400	if (ret)
3401	goto fail_sb_buffer;
3402	ret = btrfs_init_workqueues(fs_info);
3403	if (ret)
3404	goto fail_sb_buffer;
3405
3406	sb->s_bdi->ra_pages *= btrfs_super_num_devices(s: disk_super);
3407	sb->s_bdi->ra_pages = max(sb->s_bdi->ra_pages, SZ_4M / PAGE_SIZE);
3408
3409	/* Update the values for the current filesystem. */
3410	sb->s_blocksize = sectorsize;
3411	sb->s_blocksize_bits = blksize_bits(size: sectorsize);
3412	memcpy(&sb->s_uuid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE);
3413
3414	mutex_lock(&fs_info->chunk_mutex);
3415	ret = btrfs_read_sys_array(fs_info);
3416	mutex_unlock(lock: &fs_info->chunk_mutex);
3417	if (ret) {
3418	btrfs_err(fs_info, "failed to read the system array: %d", ret);
3419	goto fail_sb_buffer;
3420	}
3421
3422	generation = btrfs_super_chunk_root_generation(s: disk_super);
3423	level = btrfs_super_chunk_root_level(s: disk_super);
3424	ret = load_super_root(root: chunk_root, bytenr: btrfs_super_chunk_root(s: disk_super),
3425	gen: generation, level);
3426	if (ret) {
3427	btrfs_err(fs_info, "failed to read chunk root");
3428	goto fail_tree_roots;
3429	}
3430
3431	read_extent_buffer(eb: chunk_root->node, dst: fs_info->chunk_tree_uuid,
3432	offsetof(struct btrfs_header, chunk_tree_uuid),
3433	BTRFS_UUID_SIZE);
3434
3435	ret = btrfs_read_chunk_tree(fs_info);
3436	if (ret) {
3437	btrfs_err(fs_info, "failed to read chunk tree: %d", ret);
3438	goto fail_tree_roots;
3439	}
3440
3441	/*
3442	* At this point we know all the devices that make this filesystem,
3443	* including the seed devices but we don't know yet if the replace
3444	* target is required. So free devices that are not part of this
3445	* filesystem but skip the replace target device which is checked
3446	* below in btrfs_init_dev_replace().
3447	*/
3448	btrfs_free_extra_devids(fs_devices);
3449	if (unlikely(!fs_devices->latest_dev->bdev)) {
3450	btrfs_err(fs_info, "failed to read devices");
3451	ret = -EIO;
3452	goto fail_tree_roots;
3453	}
3454
3455	ret = init_tree_roots(fs_info);
3456	if (ret)
3457	goto fail_tree_roots;
3458
3459	/*
3460	* Get zone type information of zoned block devices. This will also
3461	* handle emulation of a zoned filesystem if a regular device has the
3462	* zoned incompat feature flag set.
3463	*/
3464	ret = btrfs_get_dev_zone_info_all_devices(fs_info);
3465	if (ret) {
3466	btrfs_err(fs_info,
3467	"zoned: failed to read device zone info: %d", ret);
3468	goto fail_block_groups;
3469	}
3470
3471	/*
3472	* If we have a uuid root and we're not being told to rescan we need to
3473	* check the generation here so we can set the
3474	* BTRFS_FS_UPDATE_UUID_TREE_GEN bit. Otherwise we could commit the
3475	* transaction during a balance or the log replay without updating the
3476	* uuid generation, and then if we crash we would rescan the uuid tree,
3477	* even though it was perfectly fine.
3478	*/
3479	if (fs_info->uuid_root && !btrfs_test_opt(fs_info, RESCAN_UUID_TREE) &&
3480	fs_info->generation == btrfs_super_uuid_tree_generation(s: disk_super))
3481	set_bit(nr: BTRFS_FS_UPDATE_UUID_TREE_GEN, addr: &fs_info->flags);
3482
3483	if (unlikely(btrfs_verify_dev_items(fs_info))) {
3484	ret = -EUCLEAN;
3485	goto fail_block_groups;
3486	}
3487	ret = btrfs_verify_dev_extents(fs_info);
3488	if (ret) {
3489	btrfs_err(fs_info,
3490	"failed to verify dev extents against chunks: %d",
3491	ret);
3492	goto fail_block_groups;
3493	}
3494	ret = btrfs_recover_balance(fs_info);
3495	if (ret) {
3496	btrfs_err(fs_info, "failed to recover balance: %d", ret);
3497	goto fail_block_groups;
3498	}
3499
3500	ret = btrfs_init_dev_stats(fs_info);
3501	if (ret) {
3502	btrfs_err(fs_info, "failed to init dev_stats: %d", ret);
3503	goto fail_block_groups;
3504	}
3505
3506	ret = btrfs_init_dev_replace(fs_info);
3507	if (ret) {
3508	btrfs_err(fs_info, "failed to init dev_replace: %d", ret);
3509	goto fail_block_groups;
3510	}
3511
3512	ret = btrfs_check_zoned_mode(fs_info);
3513	if (ret) {
3514	btrfs_err(fs_info, "failed to initialize zoned mode: %d",
3515	ret);
3516	goto fail_block_groups;
3517	}
3518
3519	ret = btrfs_sysfs_add_fsid(fs_devs: fs_devices);
3520	if (ret) {
3521	btrfs_err(fs_info, "failed to init sysfs fsid interface: %d",
3522	ret);
3523	goto fail_block_groups;
3524	}
3525
3526	ret = btrfs_sysfs_add_mounted(fs_info);
3527	if (ret) {
3528	btrfs_err(fs_info, "failed to init sysfs interface: %d", ret);
3529	goto fail_fsdev_sysfs;
3530	}
3531
3532	ret = btrfs_init_space_info(fs_info);
3533	if (ret) {
3534	btrfs_err(fs_info, "failed to initialize space info: %d", ret);
3535	goto fail_sysfs;
3536	}
3537
3538	ret = btrfs_read_block_groups(info: fs_info);
3539	if (ret) {
3540	btrfs_err(fs_info, "failed to read block groups: %d", ret);
3541	goto fail_sysfs;
3542	}
3543
3544	btrfs_zoned_reserve_data_reloc_bg(fs_info);
3545	btrfs_free_zone_cache(fs_info);
3546
3547	btrfs_check_active_zone_reservation(fs_info);
3548
3549	if (!sb_rdonly(sb) && fs_info->fs_devices->missing_devices &&
3550	!btrfs_check_rw_degradable(fs_info, NULL)) {
3551	btrfs_warn(fs_info,
3552	"writable mount is not allowed due to too many missing devices");
3553	ret = -EINVAL;
3554	goto fail_sysfs;
3555	}
3556
3557	fs_info->cleaner_kthread = kthread_run(cleaner_kthread, fs_info,
3558	"btrfs-cleaner");
3559	if (IS_ERR(ptr: fs_info->cleaner_kthread)) {
3560	ret = PTR_ERR(ptr: fs_info->cleaner_kthread);
3561	goto fail_sysfs;
3562	}
3563
3564	fs_info->transaction_kthread = kthread_run(transaction_kthread,
3565	tree_root,
3566	"btrfs-transaction");
3567	if (IS_ERR(ptr: fs_info->transaction_kthread)) {
3568	ret = PTR_ERR(ptr: fs_info->transaction_kthread);
3569	goto fail_cleaner;
3570	}
3571
3572	ret = btrfs_read_qgroup_config(fs_info);
3573	if (ret)
3574	goto fail_trans_kthread;
3575
3576	if (btrfs_build_ref_tree(fs_info))
3577	btrfs_err(fs_info, "couldn't build ref tree");
3578
3579	/* do not make disk changes in broken FS or nologreplay is given */
3580	if (btrfs_super_log_root(s: disk_super) != 0 &&
3581	!btrfs_test_opt(fs_info, NOLOGREPLAY)) {
3582	btrfs_info(fs_info, "start tree-log replay");
3583	ret = btrfs_replay_log(fs_info, fs_devices);
3584	if (ret)
3585	goto fail_qgroup;
3586	}
3587
3588	fs_info->fs_root = btrfs_get_fs_root(fs_info, BTRFS_FS_TREE_OBJECTID, check_ref: true);
3589	if (IS_ERR(ptr: fs_info->fs_root)) {
3590	ret = PTR_ERR(ptr: fs_info->fs_root);
3591	btrfs_warn(fs_info, "failed to read fs tree: %d", ret);
3592	fs_info->fs_root = NULL;
3593	goto fail_qgroup;
3594	}
3595
3596	if (sb_rdonly(sb))
3597	return 0;
3598
3599	ret = btrfs_start_pre_rw_mount(fs_info);
3600	if (ret) {
3601	close_ctree(fs_info);
3602	return ret;
3603	}
3604	btrfs_discard_resume(fs_info);
3605
3606	if (fs_info->uuid_root &&
3607	(btrfs_test_opt(fs_info, RESCAN_UUID_TREE) ||
3608	fs_info->generation != btrfs_super_uuid_tree_generation(s: disk_super))) {
3609	btrfs_info(fs_info, "checking UUID tree");
3610	ret = btrfs_check_uuid_tree(fs_info);
3611	if (ret) {
3612	btrfs_warn(fs_info,
3613	"failed to check the UUID tree: %d", ret);
3614	close_ctree(fs_info);
3615	return ret;
3616	}
3617	}
3618
3619	set_bit(nr: BTRFS_FS_OPEN, addr: &fs_info->flags);
3620
3621	/* Kick the cleaner thread so it'll start deleting snapshots. */
3622	if (test_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags))
3623	wake_up_process(tsk: fs_info->cleaner_kthread);
3624
3625	return 0;
3626
3627	fail_qgroup:
3628	btrfs_free_qgroup_config(fs_info);
3629	fail_trans_kthread:
3630	kthread_stop(k: fs_info->transaction_kthread);
3631	btrfs_cleanup_transaction(fs_info);
3632	btrfs_free_fs_roots(fs_info);
3633	fail_cleaner:
3634	kthread_stop(k: fs_info->cleaner_kthread);
3635
3636	/*
3637	* make sure we're done with the btree inode before we stop our
3638	* kthreads
3639	*/
3640	filemap_write_and_wait(mapping: fs_info->btree_inode->i_mapping);
3641
3642	fail_sysfs:
3643	btrfs_sysfs_remove_mounted(fs_info);
3644
3645	fail_fsdev_sysfs:
3646	btrfs_sysfs_remove_fsid(fs_devs: fs_info->fs_devices);
3647
3648	fail_block_groups:
3649	btrfs_put_block_group_cache(info: fs_info);
3650
3651	fail_tree_roots:
3652	if (fs_info->data_reloc_root)
3653	btrfs_drop_and_free_fs_root(fs_info, root: fs_info->data_reloc_root);
3654	free_root_pointers(info: fs_info, free_chunk_root: true);
3655	invalidate_inode_pages2(mapping: fs_info->btree_inode->i_mapping);
3656
3657	fail_sb_buffer:
3658	btrfs_stop_all_workers(fs_info);
3659	btrfs_free_block_groups(info: fs_info);
3660	fail_alloc:
3661	btrfs_mapping_tree_free(fs_info);
3662
3663	iput(fs_info->btree_inode);
3664	fail:
3665	ASSERT(ret < 0);
3666	return ret;
3667	}
3668	ALLOW_ERROR_INJECTION(open_ctree, ERRNO);
3669
3670	static void btrfs_end_super_write(struct bio *bio)
3671	{
3672	struct btrfs_device *device = bio->bi_private;
3673	struct folio_iter fi;
3674
3675	bio_for_each_folio_all(fi, bio) {
3676	if (bio->bi_status) {
3677	btrfs_warn_rl(device->fs_info,
3678	"lost super block write due to IO error on %s (%d)",
3679	btrfs_dev_name(device),
3680	blk_status_to_errno(bio->bi_status));
3681	btrfs_dev_stat_inc_and_print(dev: device,
3682	index: BTRFS_DEV_STAT_WRITE_ERRS);
3683	/* Ensure failure if the primary sb fails. */
3684	if (bio->bi_opf & REQ_FUA)
3685	atomic_add(BTRFS_SUPER_PRIMARY_WRITE_ERROR,
3686	v: &device->sb_write_errors);
3687	else
3688	atomic_inc(v: &device->sb_write_errors);
3689	}
3690	folio_unlock(folio: fi.folio);
3691	folio_put(folio: fi.folio);
3692	}
3693
3694	bio_put(bio);
3695	}
3696
3697	/*
3698	* Write superblock @sb to the @device. Do not wait for completion, all the
3699	* folios we use for writing are locked.
3700	*
3701	* Write @max_mirrors copies of the superblock, where 0 means default that fit
3702	* the expected device size at commit time. Note that max_mirrors must be
3703	* same for write and wait phases.
3704	*
3705	* Return number of errors when folio is not found or submission fails.
3706	*/
3707	static int write_dev_supers(struct btrfs_device *device,
3708	struct btrfs_super_block *sb, int max_mirrors)
3709	{
3710	struct btrfs_fs_info *fs_info = device->fs_info;
3711	struct address_space *mapping = device->bdev->bd_mapping;
3712	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
3713	int i;
3714	int ret;
3715	u64 bytenr, bytenr_orig;
3716
3717	atomic_set(v: &device->sb_write_errors, i: 0);
3718
3719	if (max_mirrors == 0)
3720	max_mirrors = BTRFS_SUPER_MIRROR_MAX;
3721
3722	shash->tfm = fs_info->csum_shash;
3723
3724	for (i = 0; i < max_mirrors; i++) {
3725	struct folio *folio;
3726	struct bio *bio;
3727	struct btrfs_super_block *disk_super;
3728	size_t offset;
3729
3730	bytenr_orig = btrfs_sb_offset(mirror: i);
3731	ret = btrfs_sb_log_location(device, mirror: i, WRITE, bytenr_ret: &bytenr);
3732	if (ret == -ENOENT) {
3733	continue;
3734	} else if (ret < 0) {
3735	btrfs_err(device->fs_info,
3736	"couldn't get super block location for mirror %d error %d",
3737	i, ret);
3738	atomic_inc(v: &device->sb_write_errors);
3739	continue;
3740	}
3741	if (bytenr + BTRFS_SUPER_INFO_SIZE >=
3742	device->commit_total_bytes)
3743	break;
3744
3745	btrfs_set_super_bytenr(s: sb, val: bytenr_orig);
3746
3747	crypto_shash_digest(desc: shash, data: (const char *)sb + BTRFS_CSUM_SIZE,
3748	BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE,
3749	out: sb->csum);
3750
3751	folio = __filemap_get_folio(mapping, index: bytenr >> PAGE_SHIFT,
3752	FGP_LOCK | FGP_ACCESSED | FGP_CREAT,
3753	GFP_NOFS);
3754	if (IS_ERR(ptr: folio)) {
3755	btrfs_err(device->fs_info,
3756	"couldn't get super block page for bytenr %llu error %ld",
3757	bytenr, PTR_ERR(folio));
3758	atomic_inc(v: &device->sb_write_errors);
3759	continue;
3760	}
3761
3762	offset = offset_in_folio(folio, bytenr);
3763	disk_super = folio_address(folio) + offset;
3764	memcpy(disk_super, sb, BTRFS_SUPER_INFO_SIZE);
3765
3766	/*
3767	* Directly use bios here instead of relying on the page cache
3768	* to do I/O, so we don't lose the ability to do integrity
3769	* checking.
3770	*/
3771	bio = bio_alloc(bdev: device->bdev, nr_vecs: 1,
3772	opf: REQ_OP_WRITE | REQ_SYNC | REQ_META | REQ_PRIO,
3773	GFP_NOFS);
3774	bio->bi_iter.bi_sector = bytenr >> SECTOR_SHIFT;
3775	bio->bi_private = device;
3776	bio->bi_end_io = btrfs_end_super_write;
3777	bio_add_folio_nofail(bio, folio, BTRFS_SUPER_INFO_SIZE, off: offset);
3778
3779	/*
3780	* We FUA only the first super block. The others we allow to
3781	* go down lazy and there's a short window where the on-disk
3782	* copies might still contain the older version.
3783	*/
3784	if (i == 0 && !btrfs_test_opt(device->fs_info, NOBARRIER))
3785	bio->bi_opf |= REQ_FUA;
3786	submit_bio(bio);
3787
3788	if (btrfs_advance_sb_log(device, mirror: i))
3789	atomic_inc(v: &device->sb_write_errors);
3790	}
3791	return atomic_read(v: &device->sb_write_errors) < i ? 0 : -1;
3792	}
3793
3794	/*
3795	* Wait for write completion of superblocks done by write_dev_supers,
3796	* @max_mirrors same for write and wait phases.
3797	*
3798	* Return -1 if primary super block write failed or when there were no super block
3799	* copies written. Otherwise 0.
3800	*/
3801	static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
3802	{
3803	int i;
3804	int errors = 0;
3805	bool primary_failed = false;
3806	int ret;
3807	u64 bytenr;
3808
3809	if (max_mirrors == 0)
3810	max_mirrors = BTRFS_SUPER_MIRROR_MAX;
3811
3812	for (i = 0; i < max_mirrors; i++) {
3813	struct folio *folio;
3814
3815	ret = btrfs_sb_log_location(device, mirror: i, READ, bytenr_ret: &bytenr);
3816	if (ret == -ENOENT) {
3817	break;
3818	} else if (ret < 0) {
3819	errors++;
3820	if (i == 0)
3821	primary_failed = true;
3822	continue;
3823	}
3824	if (bytenr + BTRFS_SUPER_INFO_SIZE >=
3825	device->commit_total_bytes)
3826	break;
3827
3828	folio = filemap_get_folio(mapping: device->bdev->bd_mapping,
3829	index: bytenr >> PAGE_SHIFT);
3830	/* If the folio has been removed, then we know it completed. */
3831	if (IS_ERR(ptr: folio))
3832	continue;
3833
3834	/* Folio will be unlocked once the write completes. */
3835	folio_wait_locked(folio);
3836	folio_put(folio);
3837	}
3838
3839	errors += atomic_read(v: &device->sb_write_errors);
3840	if (errors >= BTRFS_SUPER_PRIMARY_WRITE_ERROR)
3841	primary_failed = true;
3842	if (primary_failed) {
3843	btrfs_err(device->fs_info, "error writing primary super block to device %llu",
3844	device->devid);
3845	return -1;
3846	}
3847
3848	return errors < i ? 0 : -1;
3849	}
3850
3851	/*
3852	* endio for the write_dev_flush, this will wake anyone waiting
3853	* for the barrier when it is done
3854	*/
3855	static void btrfs_end_empty_barrier(struct bio *bio)
3856	{
3857	bio_uninit(bio);
3858	complete(bio->bi_private);
3859	}
3860
3861	/*
3862	* Submit a flush request to the device if it supports it. Error handling is
3863	* done in the waiting counterpart.
3864	*/
3865	static void write_dev_flush(struct btrfs_device *device)
3866	{
3867	struct bio *bio = &device->flush_bio;
3868
3869	device->last_flush_error = BLK_STS_OK;
3870
3871	bio_init(bio, bdev: device->bdev, NULL, max_vecs: 0,
3872	opf: REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH);
3873	bio->bi_end_io = btrfs_end_empty_barrier;
3874	init_completion(x: &device->flush_wait);
3875	bio->bi_private = &device->flush_wait;
3876	submit_bio(bio);
3877	set_bit(BTRFS_DEV_STATE_FLUSH_SENT, addr: &device->dev_state);
3878	}
3879
3880	/*
3881	* If the flush bio has been submitted by write_dev_flush, wait for it.
3882	* Return true for any error, and false otherwise.
3883	*/
3884	static bool wait_dev_flush(struct btrfs_device *device)
3885	{
3886	struct bio *bio = &device->flush_bio;
3887
3888	if (!test_and_clear_bit(BTRFS_DEV_STATE_FLUSH_SENT, addr: &device->dev_state))
3889	return false;
3890
3891	wait_for_completion_io(&device->flush_wait);
3892
3893	if (bio->bi_status) {
3894	device->last_flush_error = bio->bi_status;
3895	btrfs_dev_stat_inc_and_print(dev: device, index: BTRFS_DEV_STAT_FLUSH_ERRS);
3896	return true;
3897	}
3898
3899	return false;
3900	}
3901
3902	/*
3903	* send an empty flush down to each device in parallel,
3904	* then wait for them
3905	*/
3906	static int barrier_all_devices(struct btrfs_fs_info *info)
3907	{
3908	struct list_head *head;
3909	struct btrfs_device *dev;
3910	int errors_wait = 0;
3911
3912	lockdep_assert_held(&info->fs_devices->device_list_mutex);
3913	/* send down all the barriers */
3914	head = &info->fs_devices->devices;
3915	list_for_each_entry(dev, head, dev_list) {
3916	if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
3917	continue;
3918	if (!dev->bdev)
3919	continue;
3920	if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3921	!test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
3922	continue;
3923
3924	write_dev_flush(device: dev);
3925	}
3926
3927	/* wait for all the barriers */
3928	list_for_each_entry(dev, head, dev_list) {
3929	if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
3930	continue;
3931	if (!dev->bdev) {
3932	errors_wait++;
3933	continue;
3934	}
3935	if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3936	!test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
3937	continue;
3938
3939	if (wait_dev_flush(device: dev))
3940	errors_wait++;
3941	}
3942
3943	/*
3944	* Checks last_flush_error of disks in order to determine the device
3945	* state.
3946	*/
3947	if (unlikely(errors_wait && !btrfs_check_rw_degradable(info, NULL)))
3948	return -EIO;
3949
3950	return 0;
3951	}
3952
3953	int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags)
3954	{
3955	int raid_type;
3956	int min_tolerated = INT_MAX;
3957
3958	if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 ||
3959	(flags & BTRFS_AVAIL_ALLOC_BIT_SINGLE))
3960	min_tolerated = min_t(int, min_tolerated,
3961	btrfs_raid_array[BTRFS_RAID_SINGLE].
3962	tolerated_failures);
3963
3964	for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
3965	if (raid_type == BTRFS_RAID_SINGLE)
3966	continue;
3967	if (!(flags & btrfs_raid_array[raid_type].bg_flag))
3968	continue;
3969	min_tolerated = min_t(int, min_tolerated,
3970	btrfs_raid_array[raid_type].
3971	tolerated_failures);
3972	}
3973
3974	if (min_tolerated == INT_MAX) {
3975	btrfs_warn(NULL, "unknown raid flag: %llu", flags);
3976	min_tolerated = 0;
3977	}
3978
3979	return min_tolerated;
3980	}
3981
3982	int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors)
3983	{
3984	struct list_head *head;
3985	struct btrfs_device *dev;
3986	struct btrfs_super_block *sb;
3987	struct btrfs_dev_item *dev_item;
3988	int ret;
3989	int do_barriers;
3990	int max_errors;
3991	int total_errors = 0;
3992	u64 flags;
3993
3994	do_barriers = !btrfs_test_opt(fs_info, NOBARRIER);
3995
3996	/*
3997	* max_mirrors == 0 indicates we're from commit_transaction,
3998	* not from fsync where the tree roots in fs_info have not
3999	* been consistent on disk.
4000	*/
4001	if (max_mirrors == 0)
4002	backup_super_roots(info: fs_info);
4003
4004	sb = fs_info->super_for_commit;
4005	dev_item = &sb->dev_item;
4006
4007	mutex_lock(&fs_info->fs_devices->device_list_mutex);
4008	head = &fs_info->fs_devices->devices;
4009	max_errors = btrfs_super_num_devices(s: fs_info->super_copy) - 1;
4010
4011	if (do_barriers) {
4012	ret = barrier_all_devices(info: fs_info);
4013	if (ret) {
4014	mutex_unlock(
4015	lock: &fs_info->fs_devices->device_list_mutex);
4016	btrfs_handle_fs_error(fs_info, ret,
4017	"errors while submitting device barriers.");
4018	return ret;
4019	}
4020	}
4021
4022	list_for_each_entry(dev, head, dev_list) {
4023	if (!dev->bdev) {
4024	total_errors++;
4025	continue;
4026	}
4027	if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4028	!test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4029	continue;
4030
4031	btrfs_set_stack_device_generation(s: dev_item, val: 0);
4032	btrfs_set_stack_device_type(s: dev_item, val: dev->type);
4033	btrfs_set_stack_device_id(s: dev_item, val: dev->devid);
4034	btrfs_set_stack_device_total_bytes(s: dev_item,
4035	val: dev->commit_total_bytes);
4036	btrfs_set_stack_device_bytes_used(s: dev_item,
4037	val: dev->commit_bytes_used);
4038	btrfs_set_stack_device_io_align(s: dev_item, val: dev->io_align);
4039	btrfs_set_stack_device_io_width(s: dev_item, val: dev->io_width);
4040	btrfs_set_stack_device_sector_size(s: dev_item, val: dev->sector_size);
4041	memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
4042	memcpy(dev_item->fsid, dev->fs_devices->metadata_uuid,
4043	BTRFS_FSID_SIZE);
4044
4045	flags = btrfs_super_flags(s: sb);
4046	btrfs_set_super_flags(s: sb, val: flags | BTRFS_HEADER_FLAG_WRITTEN);
4047
4048	ret = btrfs_validate_write_super(fs_info, sb);
4049	if (unlikely(ret < 0)) {
4050	mutex_unlock(lock: &fs_info->fs_devices->device_list_mutex);
4051	btrfs_handle_fs_error(fs_info, -EUCLEAN,
4052	"unexpected superblock corruption detected");
4053	return -EUCLEAN;
4054	}
4055
4056	ret = write_dev_supers(device: dev, sb, max_mirrors);
4057	if (ret)
4058	total_errors++;
4059	}
4060	if (unlikely(total_errors > max_errors)) {
4061	btrfs_err(fs_info, "%d errors while writing supers",
4062	total_errors);
4063	mutex_unlock(lock: &fs_info->fs_devices->device_list_mutex);
4064
4065	/* FUA is masked off if unsupported and can't be the reason */
4066	btrfs_handle_fs_error(fs_info, -EIO,
4067	"%d errors while writing supers",
4068	total_errors);
4069	return -EIO;
4070	}
4071
4072	total_errors = 0;
4073	list_for_each_entry(dev, head, dev_list) {
4074	if (!dev->bdev)
4075	continue;
4076	if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4077	!test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4078	continue;
4079
4080	ret = wait_dev_supers(device: dev, max_mirrors);
4081	if (ret)
4082	total_errors++;
4083	}
4084	mutex_unlock(lock: &fs_info->fs_devices->device_list_mutex);
4085	if (unlikely(total_errors > max_errors)) {
4086	btrfs_handle_fs_error(fs_info, -EIO,
4087	"%d errors while writing supers",
4088	total_errors);
4089	return -EIO;
4090	}
4091	return 0;
4092	}
4093
4094	/* Drop a fs root from the radix tree and free it. */
4095	void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
4096	struct btrfs_root *root)
4097	{
4098	bool drop_ref = false;
4099
4100	spin_lock(lock: &fs_info->fs_roots_radix_lock);
4101	radix_tree_delete(&fs_info->fs_roots_radix,
4102	(unsigned long)btrfs_root_id(root));
4103	if (test_and_clear_bit(nr: BTRFS_ROOT_IN_RADIX, addr: &root->state))
4104	drop_ref = true;
4105	spin_unlock(lock: &fs_info->fs_roots_radix_lock);
4106
4107	if (BTRFS_FS_ERROR(fs_info)) {
4108	ASSERT(root->log_root == NULL);
4109	if (root->reloc_root) {
4110	btrfs_put_root(root: root->reloc_root);
4111	root->reloc_root = NULL;
4112	}
4113	}
4114
4115	if (drop_ref)
4116	btrfs_put_root(root);
4117	}
4118
4119	int btrfs_commit_super(struct btrfs_fs_info *fs_info)
4120	{
4121	mutex_lock(&fs_info->cleaner_mutex);
4122	btrfs_run_delayed_iputs(fs_info);
4123	mutex_unlock(lock: &fs_info->cleaner_mutex);
4124	wake_up_process(tsk: fs_info->cleaner_kthread);
4125
4126	/* wait until ongoing cleanup work done */
4127	down_write(sem: &fs_info->cleanup_work_sem);
4128	up_write(sem: &fs_info->cleanup_work_sem);
4129
4130	return btrfs_commit_current_transaction(root: fs_info->tree_root);
4131	}
4132
4133	static void warn_about_uncommitted_trans(struct btrfs_fs_info *fs_info)
4134	{
4135	struct btrfs_transaction *trans;
4136	struct btrfs_transaction *tmp;
4137	bool found = false;
4138
4139	/*
4140	* This function is only called at the very end of close_ctree(),
4141	* thus no other running transaction, no need to take trans_lock.
4142	*/
4143	ASSERT(test_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags));
4144	list_for_each_entry_safe(trans, tmp, &fs_info->trans_list, list) {
4145	struct extent_state *cached = NULL;
4146	u64 dirty_bytes = 0;
4147	u64 cur = 0;
4148	u64 found_start;
4149	u64 found_end;
4150
4151	found = true;
4152	while (btrfs_find_first_extent_bit(tree: &trans->dirty_pages, start: cur,
4153	start_ret: &found_start, end_ret: &found_end,
4154	bits: EXTENT_DIRTY, cached_state: &cached)) {
4155	dirty_bytes += found_end + 1 - found_start;
4156	cur = found_end + 1;
4157	}
4158	btrfs_warn(fs_info,
4159	"transaction %llu (with %llu dirty metadata bytes) is not committed",
4160	trans->transid, dirty_bytes);
4161	btrfs_cleanup_one_transaction(trans);
4162
4163	if (trans == fs_info->running_transaction)
4164	fs_info->running_transaction = NULL;
4165	list_del_init(entry: &trans->list);
4166
4167	btrfs_put_transaction(transaction: trans);
4168	trace_btrfs_transaction_commit(fs_info);
4169	}
4170	ASSERT(!found);
4171	}
4172
4173	void __cold close_ctree(struct btrfs_fs_info *fs_info)
4174	{
4175	int ret;
4176
4177	set_bit(nr: BTRFS_FS_CLOSING_START, addr: &fs_info->flags);
4178
4179	/*
4180	* If we had UNFINISHED_DROPS we could still be processing them, so
4181	* clear that bit and wake up relocation so it can stop.
4182	* We must do this before stopping the block group reclaim task, because
4183	* at btrfs_relocate_block_group() we wait for this bit, and after the
4184	* wait we stop with -EINTR if btrfs_fs_closing() returns non-zero - we
4185	* have just set BTRFS_FS_CLOSING_START, so btrfs_fs_closing() will
4186	* return 1.
4187	*/
4188	btrfs_wake_unfinished_drop(fs_info);
4189
4190	/*
4191	* We may have the reclaim task running and relocating a data block group,
4192	* in which case it may create delayed iputs. So stop it before we park
4193	* the cleaner kthread otherwise we can get new delayed iputs after
4194	* parking the cleaner, and that can make the async reclaim task to hang
4195	* if it's waiting for delayed iputs to complete, since the cleaner is
4196	* parked and can not run delayed iputs - this will make us hang when
4197	* trying to stop the async reclaim task.
4198	*/
4199	cancel_work_sync(work: &fs_info->reclaim_bgs_work);
4200	/*
4201	* We don't want the cleaner to start new transactions, add more delayed
4202	* iputs, etc. while we're closing. We can't use kthread_stop() yet
4203	* because that frees the task_struct, and the transaction kthread might
4204	* still try to wake up the cleaner.
4205	*/
4206	kthread_park(k: fs_info->cleaner_kthread);
4207
4208	/* wait for the qgroup rescan worker to stop */
4209	btrfs_qgroup_wait_for_completion(fs_info, interruptible: false);
4210
4211	/* wait for the uuid_scan task to finish */
4212	down(sem: &fs_info->uuid_tree_rescan_sem);
4213	/* avoid complains from lockdep et al., set sem back to initial state */
4214	up(sem: &fs_info->uuid_tree_rescan_sem);
4215
4216	/* pause restriper - we want to resume on mount */
4217	btrfs_pause_balance(fs_info);
4218
4219	btrfs_dev_replace_suspend_for_unmount(fs_info);
4220
4221	btrfs_scrub_cancel(info: fs_info);
4222
4223	/* wait for any defraggers to finish */
4224	wait_event(fs_info->transaction_wait,
4225	(atomic_read(&fs_info->defrag_running) == 0));
4226
4227	/* clear out the rbtree of defraggable inodes */
4228	btrfs_cleanup_defrag_inodes(fs_info);
4229
4230	/*
4231	* Handle the error fs first, as it will flush and wait for all ordered
4232	* extents. This will generate delayed iputs, thus we want to handle
4233	* it first.
4234	*/
4235	if (unlikely(BTRFS_FS_ERROR(fs_info)))
4236	btrfs_error_commit_super(fs_info);
4237
4238	/*
4239	* Wait for any fixup workers to complete.
4240	* If we don't wait for them here and they are still running by the time
4241	* we call kthread_stop() against the cleaner kthread further below, we
4242	* get an use-after-free on the cleaner because the fixup worker adds an
4243	* inode to the list of delayed iputs and then attempts to wakeup the
4244	* cleaner kthread, which was already stopped and destroyed. We parked
4245	* already the cleaner, but below we run all pending delayed iputs.
4246	*/
4247	btrfs_flush_workqueue(wq: fs_info->fixup_workers);
4248	/*
4249	* Similar case here, we have to wait for delalloc workers before we
4250	* proceed below and stop the cleaner kthread, otherwise we trigger a
4251	* use-after-tree on the cleaner kthread task_struct when a delalloc
4252	* worker running submit_compressed_extents() adds a delayed iput, which
4253	* does a wake up on the cleaner kthread, which was already freed below
4254	* when we call kthread_stop().
4255	*/
4256	btrfs_flush_workqueue(wq: fs_info->delalloc_workers);
4257
4258	/*
4259	* We can have ordered extents getting their last reference dropped from
4260	* the fs_info->workers queue because for async writes for data bios we
4261	* queue a work for that queue, at btrfs_wq_submit_bio(), that runs
4262	* run_one_async_done() which calls btrfs_bio_end_io() in case the bio
4263	* has an error, and that later function can do the final
4264	* btrfs_put_ordered_extent() on the ordered extent attached to the bio,
4265	* which adds a delayed iput for the inode. So we must flush the queue
4266	* so that we don't have delayed iputs after committing the current
4267	* transaction below and stopping the cleaner and transaction kthreads.
4268	*/
4269	btrfs_flush_workqueue(wq: fs_info->workers);
4270
4271	/*
4272	* When finishing a compressed write bio we schedule a work queue item
4273	* to finish an ordered extent - end_bbio_compressed_write()
4274	* calls btrfs_finish_ordered_extent() which in turns does a call to
4275	* btrfs_queue_ordered_fn(), and that queues the ordered extent
4276	* completion either in the endio_write_workers work queue or in the
4277	* fs_info->endio_freespace_worker work queue. We flush those queues
4278	* below, so before we flush them we must flush this queue for the
4279	* workers of compressed writes.
4280	*/
4281	flush_workqueue(fs_info->endio_workers);
4282
4283	/*
4284	* After we parked the cleaner kthread, ordered extents may have
4285	* completed and created new delayed iputs. If one of the async reclaim
4286	* tasks is running and in the RUN_DELAYED_IPUTS flush state, then we
4287	* can hang forever trying to stop it, because if a delayed iput is
4288	* added after it ran btrfs_run_delayed_iputs() and before it called
4289	* btrfs_wait_on_delayed_iputs(), it will hang forever since there is
4290	* no one else to run iputs.
4291	*
4292	* So wait for all ongoing ordered extents to complete and then run
4293	* delayed iputs. This works because once we reach this point no one
4294	* can create new ordered extents, but delayed iputs can still be added
4295	* by a reclaim worker (see comments further below).
4296	*
4297	* Also note that btrfs_wait_ordered_roots() is not safe here, because
4298	* it waits for BTRFS_ORDERED_COMPLETE to be set on an ordered extent,
4299	* but the delayed iput for the respective inode is made only when doing
4300	* the final btrfs_put_ordered_extent() (which must happen at
4301	* btrfs_finish_ordered_io() when we are unmounting).
4302	*/
4303	btrfs_flush_workqueue(wq: fs_info->endio_write_workers);
4304	/* Ordered extents for free space inodes. */
4305	btrfs_flush_workqueue(wq: fs_info->endio_freespace_worker);
4306	/*
4307	* Run delayed iputs in case an async reclaim worker is waiting for them
4308	* to be run as mentioned above.
4309	*/
4310	btrfs_run_delayed_iputs(fs_info);
4311
4312	cancel_work_sync(work: &fs_info->async_reclaim_work);
4313	cancel_work_sync(work: &fs_info->async_data_reclaim_work);
4314	cancel_work_sync(work: &fs_info->preempt_reclaim_work);
4315	cancel_work_sync(work: &fs_info->em_shrinker_work);
4316
4317	/*
4318	* Run delayed iputs again because an async reclaim worker may have
4319	* added new ones if it was flushing delalloc:
4320	*
4321	* shrink_delalloc() -> btrfs_start_delalloc_roots() ->
4322	* start_delalloc_inodes() -> btrfs_add_delayed_iput()
4323	*/
4324	btrfs_run_delayed_iputs(fs_info);
4325
4326	/* There should be no more workload to generate new delayed iputs. */
4327	set_bit(nr: BTRFS_FS_STATE_NO_DELAYED_IPUT, addr: &fs_info->fs_state);
4328
4329	/* Cancel or finish ongoing discard work */
4330	btrfs_discard_cleanup(fs_info);
4331
4332	if (!sb_rdonly(sb: fs_info->sb)) {
4333	/*
4334	* The cleaner kthread is stopped, so do one final pass over
4335	* unused block groups.
4336	*/
4337	btrfs_delete_unused_bgs(fs_info);
4338
4339	/*
4340	* There might be existing delayed inode workers still running
4341	* and holding an empty delayed inode item. We must wait for
4342	* them to complete first because they can create a transaction.
4343	* This happens when someone calls btrfs_balance_delayed_items()
4344	* and then a transaction commit runs the same delayed nodes
4345	* before any delayed worker has done something with the nodes.
4346	* We must wait for any worker here and not at transaction
4347	* commit time since that could cause a deadlock.
4348	* This is a very rare case.
4349	*/
4350	btrfs_flush_workqueue(wq: fs_info->delayed_workers);
4351
4352	ret = btrfs_commit_super(fs_info);
4353	if (ret)
4354	btrfs_err(fs_info, "commit super ret %d", ret);
4355	}
4356
4357	kthread_stop(k: fs_info->transaction_kthread);
4358	kthread_stop(k: fs_info->cleaner_kthread);
4359
4360	ASSERT(list_empty(&fs_info->delayed_iputs));
4361	set_bit(nr: BTRFS_FS_CLOSING_DONE, addr: &fs_info->flags);
4362
4363	if (btrfs_check_quota_leak(fs_info)) {
4364	DEBUG_WARN("qgroup reserved space leaked");
4365	btrfs_err(fs_info, "qgroup reserved space leaked");
4366	}
4367
4368	btrfs_free_qgroup_config(fs_info);
4369	ASSERT(list_empty(&fs_info->delalloc_roots));
4370
4371	if (percpu_counter_sum(fbc: &fs_info->delalloc_bytes)) {
4372	btrfs_info(fs_info, "at unmount delalloc count %lld",
4373	percpu_counter_sum(&fs_info->delalloc_bytes));
4374	}
4375
4376	if (percpu_counter_sum(fbc: &fs_info->ordered_bytes))
4377	btrfs_info(fs_info, "at unmount dio bytes count %lld",
4378	percpu_counter_sum(&fs_info->ordered_bytes));
4379
4380	btrfs_sysfs_remove_mounted(fs_info);
4381	btrfs_sysfs_remove_fsid(fs_devs: fs_info->fs_devices);
4382
4383	btrfs_put_block_group_cache(info: fs_info);
4384
4385	/*
4386	* we must make sure there is not any read request to
4387	* submit after we stopping all workers.
4388	*/
4389	invalidate_inode_pages2(mapping: fs_info->btree_inode->i_mapping);
4390	btrfs_stop_all_workers(fs_info);
4391
4392	/* We shouldn't have any transaction open at this point */
4393	warn_about_uncommitted_trans(fs_info);
4394
4395	clear_bit(nr: BTRFS_FS_OPEN, addr: &fs_info->flags);
4396	free_root_pointers(info: fs_info, free_chunk_root: true);
4397	btrfs_free_fs_roots(fs_info);
4398
4399	/*
4400	* We must free the block groups after dropping the fs_roots as we could
4401	* have had an IO error and have left over tree log blocks that aren't
4402	* cleaned up until the fs roots are freed. This makes the block group
4403	* accounting appear to be wrong because there's pending reserved bytes,
4404	* so make sure we do the block group cleanup afterwards.
4405	*/
4406	btrfs_free_block_groups(info: fs_info);
4407
4408	iput(fs_info->btree_inode);
4409
4410	btrfs_mapping_tree_free(fs_info);
4411	}
4412
4413	void btrfs_mark_buffer_dirty(struct btrfs_trans_handle *trans,
4414	struct extent_buffer *buf)
4415	{
4416	struct btrfs_fs_info *fs_info = buf->fs_info;
4417	u64 transid = btrfs_header_generation(eb: buf);
4418
4419	#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4420	/*
4421	* This is a fast path so only do this check if we have sanity tests
4422	* enabled. Normal people shouldn't be using unmapped buffers as dirty
4423	* outside of the sanity tests.
4424	*/
4425	if (unlikely(test_bit(EXTENT_BUFFER_UNMAPPED, &buf->bflags)))
4426	return;
4427	#endif
4428	/* This is an active transaction (its state < TRANS_STATE_UNBLOCKED). */
4429	ASSERT(trans->transid == fs_info->generation);
4430	btrfs_assert_tree_write_locked(eb: buf);
4431	if (unlikely(transid != fs_info->generation)) {
4432	btrfs_abort_transaction(trans, -EUCLEAN);
4433	btrfs_crit(fs_info,
4434	"dirty buffer transid mismatch, logical %llu found transid %llu running transid %llu",
4435	buf->start, transid, fs_info->generation);
4436	}
4437	set_extent_buffer_dirty(buf);
4438	}
4439
4440	static void __btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info,
4441	int flush_delayed)
4442	{
4443	/*
4444	* looks as though older kernels can get into trouble with
4445	* this code, they end up stuck in balance_dirty_pages forever
4446	*/
4447	int ret;
4448
4449	if (current->flags & PF_MEMALLOC)
4450	return;
4451
4452	if (flush_delayed)
4453	btrfs_balance_delayed_items(fs_info);
4454
4455	ret = __percpu_counter_compare(fbc: &fs_info->dirty_metadata_bytes,
4456	BTRFS_DIRTY_METADATA_THRESH,
4457	batch: fs_info->dirty_metadata_batch);
4458	if (ret > 0) {
4459	balance_dirty_pages_ratelimited(mapping: fs_info->btree_inode->i_mapping);
4460	}
4461	}
4462
4463	void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info)
4464	{
4465	__btrfs_btree_balance_dirty(fs_info, flush_delayed: 1);
4466	}
4467
4468	void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info)
4469	{
4470	__btrfs_btree_balance_dirty(fs_info, flush_delayed: 0);
4471	}
4472
4473	static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info)
4474	{
4475	/* cleanup FS via transaction */
4476	btrfs_cleanup_transaction(fs_info);
4477
4478	down_write(sem: &fs_info->cleanup_work_sem);
4479	up_write(sem: &fs_info->cleanup_work_sem);
4480	}
4481
4482	static void btrfs_drop_all_logs(struct btrfs_fs_info *fs_info)
4483	{
4484	struct btrfs_root *gang[8];
4485	u64 root_objectid = 0;
4486	int ret;
4487
4488	spin_lock(lock: &fs_info->fs_roots_radix_lock);
4489	while ((ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
4490	results: (void **)gang, first_index: root_objectid,
4491	ARRAY_SIZE(gang))) != 0) {
4492	int i;
4493
4494	for (i = 0; i < ret; i++)
4495	gang[i] = btrfs_grab_root(root: gang[i]);
4496	spin_unlock(lock: &fs_info->fs_roots_radix_lock);
4497
4498	for (i = 0; i < ret; i++) {
4499	if (!gang[i])
4500	continue;
4501	root_objectid = btrfs_root_id(root: gang[i]);
4502	btrfs_free_log(NULL, root: gang[i]);
4503	btrfs_put_root(root: gang[i]);
4504	}
4505	root_objectid++;
4506	spin_lock(lock: &fs_info->fs_roots_radix_lock);
4507	}
4508	spin_unlock(lock: &fs_info->fs_roots_radix_lock);
4509	btrfs_free_log_root_tree(NULL, fs_info);
4510	}
4511
4512	static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
4513	{
4514	struct btrfs_ordered_extent *ordered;
4515
4516	spin_lock(lock: &root->ordered_extent_lock);
4517	/*
4518	* This will just short circuit the ordered completion stuff which will
4519	* make sure the ordered extent gets properly cleaned up.
4520	*/
4521	list_for_each_entry(ordered, &root->ordered_extents,
4522	root_extent_list)
4523	set_bit(nr: BTRFS_ORDERED_IOERR, addr: &ordered->flags);
4524	spin_unlock(lock: &root->ordered_extent_lock);
4525	}
4526
4527	static void btrfs_destroy_all_ordered_extents(struct btrfs_fs_info *fs_info)
4528	{
4529	struct btrfs_root *root;
4530	LIST_HEAD(splice);
4531
4532	spin_lock(lock: &fs_info->ordered_root_lock);
4533	list_splice_init(list: &fs_info->ordered_roots, head: &splice);
4534	while (!list_empty(head: &splice)) {
4535	root = list_first_entry(&splice, struct btrfs_root,
4536	ordered_root);
4537	list_move_tail(list: &root->ordered_root,
4538	head: &fs_info->ordered_roots);
4539
4540	spin_unlock(lock: &fs_info->ordered_root_lock);
4541	btrfs_destroy_ordered_extents(root);
4542
4543	cond_resched();
4544	spin_lock(lock: &fs_info->ordered_root_lock);
4545	}
4546	spin_unlock(lock: &fs_info->ordered_root_lock);
4547
4548	/*
4549	* We need this here because if we've been flipped read-only we won't
4550	* get sync() from the umount, so we need to make sure any ordered
4551	* extents that haven't had their dirty pages IO start writeout yet
4552	* actually get run and error out properly.
4553	*/
4554	btrfs_wait_ordered_roots(fs_info, U64_MAX, NULL);
4555	}
4556
4557	static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
4558	{
4559	struct btrfs_inode *btrfs_inode;
4560	LIST_HEAD(splice);
4561
4562	spin_lock(lock: &root->delalloc_lock);
4563	list_splice_init(list: &root->delalloc_inodes, head: &splice);
4564
4565	while (!list_empty(head: &splice)) {
4566	struct inode *inode = NULL;
4567	btrfs_inode = list_first_entry(&splice, struct btrfs_inode,
4568	delalloc_inodes);
4569	btrfs_del_delalloc_inode(inode: btrfs_inode);
4570	spin_unlock(lock: &root->delalloc_lock);
4571
4572	/*
4573	* Make sure we get a live inode and that it'll not disappear
4574	* meanwhile.
4575	*/
4576	inode = igrab(&btrfs_inode->vfs_inode);
4577	if (inode) {
4578	unsigned int nofs_flag;
4579
4580	nofs_flag = memalloc_nofs_save();
4581	invalidate_inode_pages2(mapping: inode->i_mapping);
4582	memalloc_nofs_restore(flags: nofs_flag);
4583	iput(inode);
4584	}
4585	spin_lock(lock: &root->delalloc_lock);
4586	}
4587	spin_unlock(lock: &root->delalloc_lock);
4588	}
4589
4590	static void btrfs_destroy_all_delalloc_inodes(struct btrfs_fs_info *fs_info)
4591	{
4592	struct btrfs_root *root;
4593	LIST_HEAD(splice);
4594
4595	spin_lock(lock: &fs_info->delalloc_root_lock);
4596	list_splice_init(list: &fs_info->delalloc_roots, head: &splice);
4597	while (!list_empty(head: &splice)) {
4598	root = list_first_entry(&splice, struct btrfs_root,
4599	delalloc_root);
4600	root = btrfs_grab_root(root);
4601	BUG_ON(!root);
4602	spin_unlock(lock: &fs_info->delalloc_root_lock);
4603
4604	btrfs_destroy_delalloc_inodes(root);
4605	btrfs_put_root(root);
4606
4607	spin_lock(lock: &fs_info->delalloc_root_lock);
4608	}
4609	spin_unlock(lock: &fs_info->delalloc_root_lock);
4610	}
4611
4612	static void btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
4613	struct extent_io_tree *dirty_pages,
4614	int mark)
4615	{
4616	struct extent_buffer *eb;
4617	u64 start = 0;
4618	u64 end;
4619
4620	while (btrfs_find_first_extent_bit(tree: dirty_pages, start, start_ret: &start, end_ret: &end,
4621	bits: mark, NULL)) {
4622	btrfs_clear_extent_bit(tree: dirty_pages, start, end, bits: mark, NULL);
4623	while (start <= end) {
4624	eb = find_extent_buffer(fs_info, start);
4625	start += fs_info->nodesize;
4626	if (!eb)
4627	continue;
4628
4629	btrfs_tree_lock(eb);
4630	wait_on_extent_buffer_writeback(eb);
4631	btrfs_clear_buffer_dirty(NULL, buf: eb);
4632	btrfs_tree_unlock(eb);
4633
4634	free_extent_buffer_stale(eb);
4635	}
4636	}
4637	}
4638
4639	static void btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
4640	struct extent_io_tree *unpin)
4641	{
4642	u64 start;
4643	u64 end;
4644
4645	while (1) {
4646	struct extent_state *cached_state = NULL;
4647
4648	/*
4649	* The btrfs_finish_extent_commit() may get the same range as
4650	* ours between find_first_extent_bit and clear_extent_dirty.
4651	* Hence, hold the unused_bg_unpin_mutex to avoid double unpin
4652	* the same extent range.
4653	*/
4654	mutex_lock(&fs_info->unused_bg_unpin_mutex);
4655	if (!btrfs_find_first_extent_bit(tree: unpin, start: 0, start_ret: &start, end_ret: &end,
4656	bits: EXTENT_DIRTY, cached_state: &cached_state)) {
4657	mutex_unlock(lock: &fs_info->unused_bg_unpin_mutex);
4658	break;
4659	}
4660
4661	btrfs_clear_extent_dirty(tree: unpin, start, end, cached: &cached_state);
4662	btrfs_free_extent_state(state: cached_state);
4663	btrfs_error_unpin_extent_range(fs_info, start, end);
4664	mutex_unlock(lock: &fs_info->unused_bg_unpin_mutex);
4665	cond_resched();
4666	}
4667	}
4668
4669	static void btrfs_cleanup_bg_io(struct btrfs_block_group *cache)
4670	{
4671	struct inode *inode;
4672
4673	inode = cache->io_ctl.inode;
4674	if (inode) {
4675	unsigned int nofs_flag;
4676
4677	nofs_flag = memalloc_nofs_save();
4678	invalidate_inode_pages2(mapping: inode->i_mapping);
4679	memalloc_nofs_restore(flags: nofs_flag);
4680
4681	BTRFS_I(inode)->generation = 0;
4682	cache->io_ctl.inode = NULL;
4683	iput(inode);
4684	}
4685	ASSERT(cache->io_ctl.pages == NULL);
4686	btrfs_put_block_group(cache);
4687	}
4688
4689	void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *cur_trans,
4690	struct btrfs_fs_info *fs_info)
4691	{
4692	struct btrfs_block_group *cache;
4693
4694	spin_lock(lock: &cur_trans->dirty_bgs_lock);
4695	while (!list_empty(head: &cur_trans->dirty_bgs)) {
4696	cache = list_first_entry(&cur_trans->dirty_bgs,
4697	struct btrfs_block_group,
4698	dirty_list);
4699
4700	if (!list_empty(head: &cache->io_list)) {
4701	spin_unlock(lock: &cur_trans->dirty_bgs_lock);
4702	list_del_init(entry: &cache->io_list);
4703	btrfs_cleanup_bg_io(cache);
4704	spin_lock(lock: &cur_trans->dirty_bgs_lock);
4705	}
4706
4707	list_del_init(entry: &cache->dirty_list);
4708	spin_lock(lock: &cache->lock);
4709	cache->disk_cache_state = BTRFS_DC_ERROR;
4710	spin_unlock(lock: &cache->lock);
4711
4712	spin_unlock(lock: &cur_trans->dirty_bgs_lock);
4713	btrfs_put_block_group(cache);
4714	btrfs_dec_delayed_refs_rsv_bg_updates(fs_info);
4715	spin_lock(lock: &cur_trans->dirty_bgs_lock);
4716	}
4717	spin_unlock(lock: &cur_trans->dirty_bgs_lock);
4718
4719	/*
4720	* Refer to the definition of io_bgs member for details why it's safe
4721	* to use it without any locking
4722	*/
4723	while (!list_empty(head: &cur_trans->io_bgs)) {
4724	cache = list_first_entry(&cur_trans->io_bgs,
4725	struct btrfs_block_group,
4726	io_list);
4727
4728	list_del_init(entry: &cache->io_list);
4729	spin_lock(lock: &cache->lock);
4730	cache->disk_cache_state = BTRFS_DC_ERROR;
4731	spin_unlock(lock: &cache->lock);
4732	btrfs_cleanup_bg_io(cache);
4733	}
4734	}
4735
4736	static void btrfs_free_all_qgroup_pertrans(struct btrfs_fs_info *fs_info)
4737	{
4738	struct btrfs_root *gang[8];
4739	int i;
4740	int ret;
4741
4742	spin_lock(lock: &fs_info->fs_roots_radix_lock);
4743	while (1) {
4744	ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix,
4745	results: (void **)gang, first_index: 0,
4746	ARRAY_SIZE(gang),
4747	BTRFS_ROOT_TRANS_TAG);
4748	if (ret == 0)
4749	break;
4750	for (i = 0; i < ret; i++) {
4751	struct btrfs_root *root = gang[i];
4752
4753	btrfs_qgroup_free_meta_all_pertrans(root);
4754	radix_tree_tag_clear(&fs_info->fs_roots_radix,
4755	index: (unsigned long)btrfs_root_id(root),
4756	BTRFS_ROOT_TRANS_TAG);
4757	}
4758	}
4759	spin_unlock(lock: &fs_info->fs_roots_radix_lock);
4760	}
4761
4762	void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans)
4763	{
4764	struct btrfs_fs_info *fs_info = cur_trans->fs_info;
4765	struct btrfs_device *dev, *tmp;
4766
4767	btrfs_cleanup_dirty_bgs(cur_trans, fs_info);
4768	ASSERT(list_empty(&cur_trans->dirty_bgs));
4769	ASSERT(list_empty(&cur_trans->io_bgs));
4770
4771	list_for_each_entry_safe(dev, tmp, &cur_trans->dev_update_list,
4772	post_commit_list) {
4773	list_del_init(entry: &dev->post_commit_list);
4774	}
4775
4776	btrfs_destroy_delayed_refs(trans: cur_trans);
4777
4778	cur_trans->state = TRANS_STATE_COMMIT_START;
4779	wake_up(&fs_info->transaction_blocked_wait);
4780
4781	cur_trans->state = TRANS_STATE_UNBLOCKED;
4782	wake_up(&fs_info->transaction_wait);
4783
4784	btrfs_destroy_marked_extents(fs_info, dirty_pages: &cur_trans->dirty_pages,
4785	mark: EXTENT_DIRTY);
4786	btrfs_destroy_pinned_extent(fs_info, unpin: &cur_trans->pinned_extents);
4787
4788	cur_trans->state =TRANS_STATE_COMPLETED;
4789	wake_up(&cur_trans->commit_wait);
4790	}
4791
4792	static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info)
4793	{
4794	struct btrfs_transaction *t;
4795
4796	mutex_lock(&fs_info->transaction_kthread_mutex);
4797
4798	spin_lock(lock: &fs_info->trans_lock);
4799	while (!list_empty(head: &fs_info->trans_list)) {
4800	t = list_first_entry(&fs_info->trans_list,
4801	struct btrfs_transaction, list);
4802	if (t->state >= TRANS_STATE_COMMIT_PREP) {
4803	refcount_inc(r: &t->use_count);
4804	spin_unlock(lock: &fs_info->trans_lock);
4805	btrfs_wait_for_commit(fs_info, transid: t->transid);
4806	btrfs_put_transaction(transaction: t);
4807	spin_lock(lock: &fs_info->trans_lock);
4808	continue;
4809	}
4810	if (t == fs_info->running_transaction) {
4811	t->state = TRANS_STATE_COMMIT_DOING;
4812	spin_unlock(lock: &fs_info->trans_lock);
4813	/*
4814	* We wait for 0 num_writers since we don't hold a trans
4815	* handle open currently for this transaction.
4816	*/
4817	wait_event(t->writer_wait,
4818	atomic_read(&t->num_writers) == 0);
4819	} else {
4820	spin_unlock(lock: &fs_info->trans_lock);
4821	}
4822	btrfs_cleanup_one_transaction(cur_trans: t);
4823
4824	spin_lock(lock: &fs_info->trans_lock);
4825	if (t == fs_info->running_transaction)
4826	fs_info->running_transaction = NULL;
4827	list_del_init(entry: &t->list);
4828	spin_unlock(lock: &fs_info->trans_lock);
4829
4830	btrfs_put_transaction(transaction: t);
4831	trace_btrfs_transaction_commit(fs_info);
4832	spin_lock(lock: &fs_info->trans_lock);
4833	}
4834	spin_unlock(lock: &fs_info->trans_lock);
4835	btrfs_destroy_all_ordered_extents(fs_info);
4836	btrfs_destroy_delayed_inodes(fs_info);
4837	btrfs_assert_delayed_root_empty(fs_info);
4838	btrfs_destroy_all_delalloc_inodes(fs_info);
4839	btrfs_drop_all_logs(fs_info);
4840	btrfs_free_all_qgroup_pertrans(fs_info);
4841	mutex_unlock(lock: &fs_info->transaction_kthread_mutex);
4842
4843	return 0;
4844	}
4845
4846	int btrfs_init_root_free_objectid(struct btrfs_root *root)
4847	{
4848	BTRFS_PATH_AUTO_FREE(path);
4849	int ret;
4850	struct extent_buffer *l;
4851	struct btrfs_key search_key;
4852	struct btrfs_key found_key;
4853	int slot;
4854
4855	path = btrfs_alloc_path();
4856	if (!path)
4857	return -ENOMEM;
4858
4859	search_key.objectid = BTRFS_LAST_FREE_OBJECTID;
4860	search_key.type = -1;
4861	search_key.offset = (u64)-1;
4862	ret = btrfs_search_slot(NULL, root, key: &search_key, p: path, ins_len: 0, cow: 0);
4863	if (ret < 0)
4864	return ret;
4865	if (unlikely(ret == 0)) {
4866	/*
4867	* Key with offset -1 found, there would have to exist a root
4868	* with such id, but this is out of valid range.
4869	*/
4870	return -EUCLEAN;
4871	}
4872	if (path->slots[0] > 0) {
4873	slot = path->slots[0] - 1;
4874	l = path->nodes[0];
4875	btrfs_item_key_to_cpu(eb: l, cpu_key: &found_key, nr: slot);
4876	root->free_objectid = max_t(u64, found_key.objectid + 1,
4877	BTRFS_FIRST_FREE_OBJECTID);
4878	} else {
4879	root->free_objectid = BTRFS_FIRST_FREE_OBJECTID;
4880	}
4881
4882	return 0;
4883	}
4884
4885	int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid)
4886	{
4887	int ret;
4888	mutex_lock(&root->objectid_mutex);
4889
4890	if (unlikely(root->free_objectid >= BTRFS_LAST_FREE_OBJECTID)) {
4891	btrfs_warn(root->fs_info,
4892	"the objectid of root %llu reaches its highest value",
4893	btrfs_root_id(root));
4894	ret = -ENOSPC;
4895	goto out;
4896	}
4897
4898	*objectid = root->free_objectid++;
4899	ret = 0;
4900	out:
4901	mutex_unlock(lock: &root->objectid_mutex);
4902	return ret;
4903	}
4904