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v6.8
   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 <asm/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 "rcu-string.h"
  33#include "dev-replace.h"
  34#include "raid56.h"
  35#include "sysfs.h"
  36#include "qgroup.h"
  37#include "compression.h"
  38#include "tree-checker.h"
  39#include "ref-verify.h"
  40#include "block-group.h"
  41#include "discard.h"
  42#include "space-info.h"
  43#include "zoned.h"
  44#include "subpage.h"
  45#include "fs.h"
  46#include "accessors.h"
  47#include "extent-tree.h"
  48#include "root-tree.h"
  49#include "defrag.h"
  50#include "uuid-tree.h"
  51#include "relocation.h"
  52#include "scrub.h"
  53#include "super.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
 
 
 
 
 
 
 
 
 
  62static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info);
  63static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info);
  64
  65static void btrfs_free_csum_hash(struct btrfs_fs_info *fs_info)
  66{
  67	if (fs_info->csum_shash)
  68		crypto_free_shash(fs_info->csum_shash);
  69}
  70
  71/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  72 * Compute the csum of a btree block and store the result to provided buffer.
  73 */
  74static 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(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(buf->folios[0]);
  93		first_page_part = min_t(u32, PAGE_SIZE, fs_info->nodesize);
  94		num_pages = num_extent_pages(buf);
  95	}
  96
  97	crypto_shash_update(shash, kaddr + BTRFS_CSUM_SIZE,
  98			    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(buf->folios[i]);
 108		crypto_shash_update(shash, kaddr, PAGE_SIZE);
 109	}
 110	memset(result, 0, BTRFS_CSUM_SIZE);
 111	crypto_shash_final(shash, 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 */
 120int btrfs_buffer_uptodate(struct extent_buffer *eb, u64 parent_transid, int 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
 143static 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 */
 160int 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(shash, (const u8 *)disk_sb + BTRFS_CSUM_SIZE,
 174			    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE, result);
 175
 176	if (memcmp(disk_sb->csum, result, fs_info->csum_size))
 177		return 1;
 178
 179	return 0;
 180}
 181
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 182static 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	int num_folios = num_extent_folios(eb);
 
 187	int ret = 0;
 188
 189	if (sb_rdonly(fs_info->sb))
 190		return -EROFS;
 191
 192	for (int i = 0; i < num_folios; i++) {
 193		struct folio *folio = eb->folios[i];
 194		u64 start = max_t(u64, eb->start, folio_pos(folio));
 195		u64 end = min_t(u64, eb->start + eb->len,
 196				folio_pos(folio) + folio_size(folio));
 197		u32 len = end - start;
 198
 199		ret = btrfs_repair_io_failure(fs_info, 0, start, len,
 200					      start, folio, offset_in_folio(folio, start),
 201					      mirror_num);
 202		if (ret)
 203			break;
 
 204	}
 205
 206	return ret;
 207}
 208
 209/*
 210 * helper to read a given tree block, doing retries as required when
 211 * the checksums don't match and we have alternate mirrors to try.
 212 *
 213 * @check:		expected tree parentness check, see the comments of the
 214 *			structure for details.
 215 */
 216int btrfs_read_extent_buffer(struct extent_buffer *eb,
 217			     struct btrfs_tree_parent_check *check)
 218{
 219	struct btrfs_fs_info *fs_info = eb->fs_info;
 220	int failed = 0;
 221	int ret;
 222	int num_copies = 0;
 223	int mirror_num = 0;
 224	int failed_mirror = 0;
 225
 226	ASSERT(check);
 227
 228	while (1) {
 229		clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 230		ret = read_extent_buffer_pages(eb, WAIT_COMPLETE, mirror_num, check);
 231		if (!ret)
 232			break;
 233
 234		num_copies = btrfs_num_copies(fs_info,
 235					      eb->start, eb->len);
 236		if (num_copies == 1)
 237			break;
 238
 239		if (!failed_mirror) {
 240			failed = 1;
 241			failed_mirror = eb->read_mirror;
 242		}
 243
 244		mirror_num++;
 245		if (mirror_num == failed_mirror)
 246			mirror_num++;
 247
 248		if (mirror_num > num_copies)
 249			break;
 250	}
 251
 252	if (failed && !ret && failed_mirror)
 253		btrfs_repair_eb_io_failure(eb, failed_mirror);
 254
 255	return ret;
 256}
 257
 258/*
 259 * Checksum a dirty tree block before IO.
 260 */
 261blk_status_t btree_csum_one_bio(struct btrfs_bio *bbio)
 262{
 263	struct extent_buffer *eb = bbio->private;
 264	struct btrfs_fs_info *fs_info = eb->fs_info;
 265	u64 found_start = btrfs_header_bytenr(eb);
 266	u64 last_trans;
 267	u8 result[BTRFS_CSUM_SIZE];
 268	int ret;
 269
 270	/* Btree blocks are always contiguous on disk. */
 271	if (WARN_ON_ONCE(bbio->file_offset != eb->start))
 272		return BLK_STS_IOERR;
 273	if (WARN_ON_ONCE(bbio->bio.bi_iter.bi_size != eb->len))
 274		return BLK_STS_IOERR;
 275
 276	/*
 277	 * If an extent_buffer is marked as EXTENT_BUFFER_ZONED_ZEROOUT, don't
 278	 * checksum it but zero-out its content. This is done to preserve
 279	 * ordering of I/O without unnecessarily writing out data.
 280	 */
 281	if (test_bit(EXTENT_BUFFER_ZONED_ZEROOUT, &eb->bflags)) {
 282		memzero_extent_buffer(eb, 0, eb->len);
 283		return BLK_STS_OK;
 284	}
 285
 286	if (WARN_ON_ONCE(found_start != eb->start))
 287		return BLK_STS_IOERR;
 288	if (WARN_ON(!btrfs_folio_test_uptodate(fs_info, eb->folios[0],
 289					       eb->start, eb->len)))
 290		return BLK_STS_IOERR;
 291
 292	ASSERT(memcmp_extent_buffer(eb, fs_info->fs_devices->metadata_uuid,
 293				    offsetof(struct btrfs_header, fsid),
 294				    BTRFS_FSID_SIZE) == 0);
 295	csum_tree_block(eb, result);
 296
 297	if (btrfs_header_level(eb))
 298		ret = btrfs_check_node(eb);
 299	else
 300		ret = btrfs_check_leaf(eb);
 301
 302	if (ret < 0)
 303		goto error;
 304
 305	/*
 306	 * Also check the generation, the eb reached here must be newer than
 307	 * last committed. Or something seriously wrong happened.
 308	 */
 309	last_trans = btrfs_get_last_trans_committed(fs_info);
 310	if (unlikely(btrfs_header_generation(eb) <= last_trans)) {
 311		ret = -EUCLEAN;
 312		btrfs_err(fs_info,
 313			"block=%llu bad generation, have %llu expect > %llu",
 314			  eb->start, btrfs_header_generation(eb), last_trans);
 
 315		goto error;
 316	}
 317	write_extent_buffer(eb, result, 0, fs_info->csum_size);
 318	return BLK_STS_OK;
 
 319
 320error:
 321	btrfs_print_tree(eb, 0);
 322	btrfs_err(fs_info, "block=%llu write time tree block corruption detected",
 323		  eb->start);
 324	/*
 325	 * Be noisy if this is an extent buffer from a log tree. We don't abort
 326	 * a transaction in case there's a bad log tree extent buffer, we just
 327	 * fallback to a transaction commit. Still we want to know when there is
 328	 * a bad log tree extent buffer, as that may signal a bug somewhere.
 329	 */
 330	WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG) ||
 331		btrfs_header_owner(eb) == BTRFS_TREE_LOG_OBJECTID);
 332	return errno_to_blk_status(ret);
 333}
 334
 335static bool check_tree_block_fsid(struct extent_buffer *eb)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 336{
 337	struct btrfs_fs_info *fs_info = eb->fs_info;
 338	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
 339	u8 fsid[BTRFS_FSID_SIZE];
 
 340
 341	read_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid),
 342			   BTRFS_FSID_SIZE);
 343
 344	/*
 345	 * alloc_fsid_devices() copies the fsid into fs_devices::metadata_uuid.
 346	 * This is then overwritten by metadata_uuid if it is present in the
 347	 * device_list_add(). The same true for a seed device as well. So use of
 348	 * fs_devices::metadata_uuid is appropriate here.
 349	 */
 350	if (memcmp(fsid, fs_info->fs_devices->metadata_uuid, BTRFS_FSID_SIZE) == 0)
 351		return false;
 
 
 
 
 
 352
 353	list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list)
 354		if (!memcmp(fsid, seed_devs->fsid, BTRFS_FSID_SIZE))
 355			return false;
 356
 357	return true;
 358}
 359
 360/* Do basic extent buffer checks at read time */
 361int btrfs_validate_extent_buffer(struct extent_buffer *eb,
 362				 struct btrfs_tree_parent_check *check)
 363{
 364	struct btrfs_fs_info *fs_info = eb->fs_info;
 365	u64 found_start;
 366	const u32 csum_size = fs_info->csum_size;
 367	u8 found_level;
 368	u8 result[BTRFS_CSUM_SIZE];
 369	const u8 *header_csum;
 370	int ret = 0;
 371
 372	ASSERT(check);
 373
 374	found_start = btrfs_header_bytenr(eb);
 375	if (found_start != eb->start) {
 376		btrfs_err_rl(fs_info,
 377			"bad tree block start, mirror %u want %llu have %llu",
 378			     eb->read_mirror, eb->start, found_start);
 379		ret = -EIO;
 380		goto out;
 381	}
 382	if (check_tree_block_fsid(eb)) {
 383		btrfs_err_rl(fs_info, "bad fsid on logical %llu mirror %u",
 384			     eb->start, eb->read_mirror);
 385		ret = -EIO;
 386		goto out;
 387	}
 388	found_level = btrfs_header_level(eb);
 389	if (found_level >= BTRFS_MAX_LEVEL) {
 390		btrfs_err(fs_info,
 391			"bad tree block level, mirror %u level %d on logical %llu",
 392			eb->read_mirror, btrfs_header_level(eb), eb->start);
 393		ret = -EIO;
 394		goto out;
 395	}
 396
 397	csum_tree_block(eb, result);
 398	header_csum = folio_address(eb->folios[0]) +
 399		get_eb_offset_in_folio(eb, offsetof(struct btrfs_header, csum));
 400
 401	if (memcmp(result, header_csum, csum_size) != 0) {
 402		btrfs_warn_rl(fs_info,
 403"checksum verify failed on logical %llu mirror %u wanted " CSUM_FMT " found " CSUM_FMT " level %d",
 404			      eb->start, eb->read_mirror,
 405			      CSUM_FMT_VALUE(csum_size, header_csum),
 406			      CSUM_FMT_VALUE(csum_size, result),
 407			      btrfs_header_level(eb));
 408		ret = -EUCLEAN;
 409		goto out;
 410	}
 411
 412	if (found_level != check->level) {
 413		btrfs_err(fs_info,
 414		"level verify failed on logical %llu mirror %u wanted %u found %u",
 415			  eb->start, eb->read_mirror, check->level, found_level);
 416		ret = -EIO;
 417		goto out;
 418	}
 419	if (unlikely(check->transid &&
 420		     btrfs_header_generation(eb) != check->transid)) {
 421		btrfs_err_rl(eb->fs_info,
 422"parent transid verify failed on logical %llu mirror %u wanted %llu found %llu",
 423				eb->start, eb->read_mirror, check->transid,
 424				btrfs_header_generation(eb));
 425		ret = -EIO;
 426		goto out;
 427	}
 428	if (check->has_first_key) {
 429		struct btrfs_key *expect_key = &check->first_key;
 430		struct btrfs_key found_key;
 431
 432		if (found_level)
 433			btrfs_node_key_to_cpu(eb, &found_key, 0);
 434		else
 435			btrfs_item_key_to_cpu(eb, &found_key, 0);
 436		if (unlikely(btrfs_comp_cpu_keys(expect_key, &found_key))) {
 437			btrfs_err(fs_info,
 438"tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
 439				  eb->start, check->transid,
 440				  expect_key->objectid,
 441				  expect_key->type, expect_key->offset,
 442				  found_key.objectid, found_key.type,
 443				  found_key.offset);
 444			ret = -EUCLEAN;
 445			goto out;
 446		}
 447	}
 448	if (check->owner_root) {
 449		ret = btrfs_check_eb_owner(eb, check->owner_root);
 450		if (ret < 0)
 451			goto out;
 452	}
 453
 454	/*
 455	 * If this is a leaf block and it is corrupt, set the corrupt bit so
 456	 * that we don't try and read the other copies of this block, just
 457	 * return -EIO.
 458	 */
 459	if (found_level == 0 && btrfs_check_leaf(eb)) {
 460		set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 461		ret = -EIO;
 462	}
 463
 464	if (found_level > 0 && btrfs_check_node(eb))
 465		ret = -EIO;
 466
 467	if (ret)
 
 
 468		btrfs_err(fs_info,
 469		"read time tree block corruption detected on logical %llu mirror %u",
 470			  eb->start, eb->read_mirror);
 471out:
 472	return ret;
 473}
 474
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 475#ifdef CONFIG_MIGRATION
 476static int btree_migrate_folio(struct address_space *mapping,
 477		struct folio *dst, struct folio *src, enum migrate_mode mode)
 478{
 479	/*
 480	 * we can't safely write a btree page from here,
 481	 * we haven't done the locking hook
 482	 */
 483	if (folio_test_dirty(src))
 484		return -EAGAIN;
 485	/*
 486	 * Buffers may be managed in a filesystem specific way.
 487	 * We must have no buffers or drop them.
 488	 */
 489	if (folio_get_private(src) &&
 490	    !filemap_release_folio(src, GFP_KERNEL))
 491		return -EAGAIN;
 492	return migrate_folio(mapping, dst, src, mode);
 493}
 494#else
 495#define btree_migrate_folio NULL
 496#endif
 497
 498static int btree_writepages(struct address_space *mapping,
 499			    struct writeback_control *wbc)
 500{
 501	struct btrfs_fs_info *fs_info;
 502	int ret;
 503
 504	if (wbc->sync_mode == WB_SYNC_NONE) {
 505
 506		if (wbc->for_kupdate)
 507			return 0;
 508
 509		fs_info = BTRFS_I(mapping->host)->root->fs_info;
 510		/* this is a bit racy, but that's ok */
 511		ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
 512					     BTRFS_DIRTY_METADATA_THRESH,
 513					     fs_info->dirty_metadata_batch);
 514		if (ret < 0)
 515			return 0;
 516	}
 517	return btree_write_cache_pages(mapping, wbc);
 518}
 519
 520static bool btree_release_folio(struct folio *folio, gfp_t gfp_flags)
 521{
 522	if (folio_test_writeback(folio) || folio_test_dirty(folio))
 523		return false;
 524
 525	return try_release_extent_buffer(&folio->page);
 526}
 527
 528static void btree_invalidate_folio(struct folio *folio, size_t offset,
 529				 size_t length)
 530{
 531	struct extent_io_tree *tree;
 532	tree = &BTRFS_I(folio->mapping->host)->io_tree;
 533	extent_invalidate_folio(tree, folio, offset);
 534	btree_release_folio(folio, GFP_NOFS);
 535	if (folio_get_private(folio)) {
 536		btrfs_warn(BTRFS_I(folio->mapping->host)->root->fs_info,
 537			   "folio private not zero on folio %llu",
 538			   (unsigned long long)folio_pos(folio));
 539		folio_detach_private(folio);
 540	}
 541}
 542
 543#ifdef DEBUG
 544static bool btree_dirty_folio(struct address_space *mapping,
 545		struct folio *folio)
 546{
 547	struct btrfs_fs_info *fs_info = btrfs_sb(mapping->host->i_sb);
 548	struct btrfs_subpage_info *spi = fs_info->subpage_info;
 549	struct btrfs_subpage *subpage;
 550	struct extent_buffer *eb;
 551	int cur_bit = 0;
 552	u64 page_start = folio_pos(folio);
 553
 554	if (fs_info->sectorsize == PAGE_SIZE) {
 555		eb = folio_get_private(folio);
 556		BUG_ON(!eb);
 557		BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
 558		BUG_ON(!atomic_read(&eb->refs));
 559		btrfs_assert_tree_write_locked(eb);
 560		return filemap_dirty_folio(mapping, folio);
 561	}
 562
 563	ASSERT(spi);
 564	subpage = folio_get_private(folio);
 565
 566	for (cur_bit = spi->dirty_offset;
 567	     cur_bit < spi->dirty_offset + spi->bitmap_nr_bits;
 568	     cur_bit++) {
 569		unsigned long flags;
 570		u64 cur;
 
 571
 572		spin_lock_irqsave(&subpage->lock, flags);
 573		if (!test_bit(cur_bit, subpage->bitmaps)) {
 574			spin_unlock_irqrestore(&subpage->lock, flags);
 
 575			continue;
 576		}
 577		spin_unlock_irqrestore(&subpage->lock, flags);
 578		cur = page_start + cur_bit * fs_info->sectorsize;
 579
 580		eb = find_extent_buffer(fs_info, cur);
 581		ASSERT(eb);
 582		ASSERT(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
 583		ASSERT(atomic_read(&eb->refs));
 584		btrfs_assert_tree_write_locked(eb);
 585		free_extent_buffer(eb);
 586
 587		cur_bit += (fs_info->nodesize >> fs_info->sectorsize_bits) - 1;
 588	}
 589	return filemap_dirty_folio(mapping, folio);
 590}
 591#else
 592#define btree_dirty_folio filemap_dirty_folio
 593#endif
 594
 595static const struct address_space_operations btree_aops = {
 596	.writepages	= btree_writepages,
 597	.release_folio	= btree_release_folio,
 598	.invalidate_folio = btree_invalidate_folio,
 599	.migrate_folio	= btree_migrate_folio,
 600	.dirty_folio	= btree_dirty_folio,
 601};
 602
 603struct extent_buffer *btrfs_find_create_tree_block(
 604						struct btrfs_fs_info *fs_info,
 605						u64 bytenr, u64 owner_root,
 606						int level)
 607{
 608	if (btrfs_is_testing(fs_info))
 609		return alloc_test_extent_buffer(fs_info, bytenr);
 610	return alloc_extent_buffer(fs_info, bytenr, owner_root, level);
 611}
 612
 613/*
 614 * Read tree block at logical address @bytenr and do variant basic but critical
 615 * verification.
 616 *
 617 * @check:		expected tree parentness check, see comments of the
 618 *			structure for details.
 619 */
 620struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
 621				      struct btrfs_tree_parent_check *check)
 622{
 623	struct extent_buffer *buf = NULL;
 624	int ret;
 625
 626	ASSERT(check);
 627
 628	buf = btrfs_find_create_tree_block(fs_info, bytenr, check->owner_root,
 629					   check->level);
 630	if (IS_ERR(buf))
 631		return buf;
 632
 633	ret = btrfs_read_extent_buffer(buf, check);
 634	if (ret) {
 635		free_extent_buffer_stale(buf);
 636		return ERR_PTR(ret);
 637	}
 638	if (btrfs_check_eb_owner(buf, check->owner_root)) {
 639		free_extent_buffer_stale(buf);
 640		return ERR_PTR(-EUCLEAN);
 641	}
 642	return buf;
 643
 644}
 645
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 646static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
 647			 u64 objectid)
 648{
 649	bool dummy = test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state);
 650
 651	memset(&root->root_key, 0, sizeof(root->root_key));
 652	memset(&root->root_item, 0, sizeof(root->root_item));
 653	memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
 654	root->fs_info = fs_info;
 655	root->root_key.objectid = objectid;
 656	root->node = NULL;
 657	root->commit_root = NULL;
 658	root->state = 0;
 659	RB_CLEAR_NODE(&root->rb_node);
 660
 661	root->last_trans = 0;
 662	root->free_objectid = 0;
 663	root->nr_delalloc_inodes = 0;
 664	root->nr_ordered_extents = 0;
 665	root->inode_tree = RB_ROOT;
 666	/* GFP flags are compatible with XA_FLAGS_*. */
 667	xa_init_flags(&root->delayed_nodes, GFP_ATOMIC);
 668
 669	btrfs_init_root_block_rsv(root);
 670
 671	INIT_LIST_HEAD(&root->dirty_list);
 672	INIT_LIST_HEAD(&root->root_list);
 673	INIT_LIST_HEAD(&root->delalloc_inodes);
 674	INIT_LIST_HEAD(&root->delalloc_root);
 675	INIT_LIST_HEAD(&root->ordered_extents);
 676	INIT_LIST_HEAD(&root->ordered_root);
 677	INIT_LIST_HEAD(&root->reloc_dirty_list);
 
 
 678	spin_lock_init(&root->inode_lock);
 679	spin_lock_init(&root->delalloc_lock);
 680	spin_lock_init(&root->ordered_extent_lock);
 681	spin_lock_init(&root->accounting_lock);
 
 
 682	spin_lock_init(&root->qgroup_meta_rsv_lock);
 683	mutex_init(&root->objectid_mutex);
 684	mutex_init(&root->log_mutex);
 685	mutex_init(&root->ordered_extent_mutex);
 686	mutex_init(&root->delalloc_mutex);
 687	init_waitqueue_head(&root->qgroup_flush_wait);
 688	init_waitqueue_head(&root->log_writer_wait);
 689	init_waitqueue_head(&root->log_commit_wait[0]);
 690	init_waitqueue_head(&root->log_commit_wait[1]);
 691	INIT_LIST_HEAD(&root->log_ctxs[0]);
 692	INIT_LIST_HEAD(&root->log_ctxs[1]);
 693	atomic_set(&root->log_commit[0], 0);
 694	atomic_set(&root->log_commit[1], 0);
 695	atomic_set(&root->log_writers, 0);
 696	atomic_set(&root->log_batch, 0);
 697	refcount_set(&root->refs, 1);
 698	atomic_set(&root->snapshot_force_cow, 0);
 699	atomic_set(&root->nr_swapfiles, 0);
 700	btrfs_set_root_log_transid(root, 0);
 701	root->log_transid_committed = -1;
 702	btrfs_set_root_last_log_commit(root, 0);
 703	root->anon_dev = 0;
 704	if (!dummy) {
 705		extent_io_tree_init(fs_info, &root->dirty_log_pages,
 706				    IO_TREE_ROOT_DIRTY_LOG_PAGES);
 707		extent_io_tree_init(fs_info, &root->log_csum_range,
 708				    IO_TREE_LOG_CSUM_RANGE);
 709	}
 710
 711	spin_lock_init(&root->root_item_lock);
 712	btrfs_qgroup_init_swapped_blocks(&root->swapped_blocks);
 713#ifdef CONFIG_BTRFS_DEBUG
 714	INIT_LIST_HEAD(&root->leak_list);
 715	spin_lock(&fs_info->fs_roots_radix_lock);
 716	list_add_tail(&root->leak_list, &fs_info->allocated_roots);
 717	spin_unlock(&fs_info->fs_roots_radix_lock);
 718#endif
 719}
 720
 721static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info,
 722					   u64 objectid, gfp_t flags)
 723{
 724	struct btrfs_root *root = kzalloc(sizeof(*root), flags);
 725	if (root)
 726		__setup_root(root, fs_info, objectid);
 727	return root;
 728}
 729
 730#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 731/* Should only be used by the testing infrastructure */
 732struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info)
 733{
 734	struct btrfs_root *root;
 735
 736	if (!fs_info)
 737		return ERR_PTR(-EINVAL);
 738
 739	root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID, GFP_KERNEL);
 740	if (!root)
 741		return ERR_PTR(-ENOMEM);
 742
 743	/* We don't use the stripesize in selftest, set it as sectorsize */
 744	root->alloc_bytenr = 0;
 745
 746	return root;
 747}
 748#endif
 749
 750static int global_root_cmp(struct rb_node *a_node, const struct rb_node *b_node)
 751{
 752	const struct btrfs_root *a = rb_entry(a_node, struct btrfs_root, rb_node);
 753	const struct btrfs_root *b = rb_entry(b_node, struct btrfs_root, rb_node);
 754
 755	return btrfs_comp_cpu_keys(&a->root_key, &b->root_key);
 756}
 757
 758static int global_root_key_cmp(const void *k, const struct rb_node *node)
 759{
 760	const struct btrfs_key *key = k;
 761	const struct btrfs_root *root = rb_entry(node, struct btrfs_root, rb_node);
 762
 763	return btrfs_comp_cpu_keys(key, &root->root_key);
 764}
 765
 766int btrfs_global_root_insert(struct btrfs_root *root)
 767{
 768	struct btrfs_fs_info *fs_info = root->fs_info;
 769	struct rb_node *tmp;
 770	int ret = 0;
 771
 772	write_lock(&fs_info->global_root_lock);
 773	tmp = rb_find_add(&root->rb_node, &fs_info->global_root_tree, global_root_cmp);
 774	write_unlock(&fs_info->global_root_lock);
 
 775
 776	if (tmp) {
 777		ret = -EEXIST;
 778		btrfs_warn(fs_info, "global root %llu %llu already exists",
 779				root->root_key.objectid, root->root_key.offset);
 780	}
 781	return ret;
 782}
 783
 784void btrfs_global_root_delete(struct btrfs_root *root)
 785{
 786	struct btrfs_fs_info *fs_info = root->fs_info;
 787
 788	write_lock(&fs_info->global_root_lock);
 789	rb_erase(&root->rb_node, &fs_info->global_root_tree);
 790	write_unlock(&fs_info->global_root_lock);
 791}
 792
 793struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info,
 794				     struct btrfs_key *key)
 795{
 796	struct rb_node *node;
 797	struct btrfs_root *root = NULL;
 798
 799	read_lock(&fs_info->global_root_lock);
 800	node = rb_find(key, &fs_info->global_root_tree, global_root_key_cmp);
 801	if (node)
 802		root = container_of(node, struct btrfs_root, rb_node);
 803	read_unlock(&fs_info->global_root_lock);
 804
 805	return root;
 806}
 807
 808static u64 btrfs_global_root_id(struct btrfs_fs_info *fs_info, u64 bytenr)
 809{
 810	struct btrfs_block_group *block_group;
 811	u64 ret;
 812
 813	if (!btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
 814		return 0;
 815
 816	if (bytenr)
 817		block_group = btrfs_lookup_block_group(fs_info, bytenr);
 818	else
 819		block_group = btrfs_lookup_first_block_group(fs_info, bytenr);
 820	ASSERT(block_group);
 821	if (!block_group)
 822		return 0;
 823	ret = block_group->global_root_id;
 824	btrfs_put_block_group(block_group);
 825
 826	return ret;
 827}
 828
 829struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr)
 830{
 831	struct btrfs_key key = {
 832		.objectid = BTRFS_CSUM_TREE_OBJECTID,
 833		.type = BTRFS_ROOT_ITEM_KEY,
 834		.offset = btrfs_global_root_id(fs_info, bytenr),
 835	};
 836
 837	return btrfs_global_root(fs_info, &key);
 838}
 839
 840struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr)
 841{
 842	struct btrfs_key key = {
 843		.objectid = BTRFS_EXTENT_TREE_OBJECTID,
 844		.type = BTRFS_ROOT_ITEM_KEY,
 845		.offset = btrfs_global_root_id(fs_info, bytenr),
 846	};
 847
 848	return btrfs_global_root(fs_info, &key);
 849}
 850
 851struct btrfs_root *btrfs_block_group_root(struct btrfs_fs_info *fs_info)
 852{
 853	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE))
 854		return fs_info->block_group_root;
 855	return btrfs_extent_root(fs_info, 0);
 856}
 857
 858struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
 859				     u64 objectid)
 860{
 861	struct btrfs_fs_info *fs_info = trans->fs_info;
 862	struct extent_buffer *leaf;
 863	struct btrfs_root *tree_root = fs_info->tree_root;
 864	struct btrfs_root *root;
 865	struct btrfs_key key;
 866	unsigned int nofs_flag;
 867	int ret = 0;
 868
 869	/*
 870	 * We're holding a transaction handle, so use a NOFS memory allocation
 871	 * context to avoid deadlock if reclaim happens.
 872	 */
 873	nofs_flag = memalloc_nofs_save();
 874	root = btrfs_alloc_root(fs_info, objectid, GFP_KERNEL);
 875	memalloc_nofs_restore(nofs_flag);
 876	if (!root)
 877		return ERR_PTR(-ENOMEM);
 878
 879	root->root_key.objectid = objectid;
 880	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
 881	root->root_key.offset = 0;
 882
 883	leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0,
 884				      0, BTRFS_NESTING_NORMAL);
 885	if (IS_ERR(leaf)) {
 886		ret = PTR_ERR(leaf);
 887		leaf = NULL;
 888		goto fail;
 889	}
 890
 891	root->node = leaf;
 892	btrfs_mark_buffer_dirty(trans, leaf);
 893
 894	root->commit_root = btrfs_root_node(root);
 895	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
 896
 897	btrfs_set_root_flags(&root->root_item, 0);
 898	btrfs_set_root_limit(&root->root_item, 0);
 899	btrfs_set_root_bytenr(&root->root_item, leaf->start);
 900	btrfs_set_root_generation(&root->root_item, trans->transid);
 901	btrfs_set_root_level(&root->root_item, 0);
 902	btrfs_set_root_refs(&root->root_item, 1);
 903	btrfs_set_root_used(&root->root_item, leaf->len);
 904	btrfs_set_root_last_snapshot(&root->root_item, 0);
 905	btrfs_set_root_dirid(&root->root_item, 0);
 906	if (is_fstree(objectid))
 907		generate_random_guid(root->root_item.uuid);
 908	else
 909		export_guid(root->root_item.uuid, &guid_null);
 910	btrfs_set_root_drop_level(&root->root_item, 0);
 911
 912	btrfs_tree_unlock(leaf);
 913
 914	key.objectid = objectid;
 915	key.type = BTRFS_ROOT_ITEM_KEY;
 916	key.offset = 0;
 917	ret = btrfs_insert_root(trans, tree_root, &key, &root->root_item);
 918	if (ret)
 919		goto fail;
 920
 921	return root;
 922
 923fail:
 924	btrfs_put_root(root);
 925
 926	return ERR_PTR(ret);
 927}
 928
 929static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
 930					 struct btrfs_fs_info *fs_info)
 931{
 932	struct btrfs_root *root;
 933
 934	root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID, GFP_NOFS);
 935	if (!root)
 936		return ERR_PTR(-ENOMEM);
 937
 938	root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
 939	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
 940	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
 941
 942	return root;
 943}
 944
 945int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
 946			      struct btrfs_root *root)
 947{
 948	struct extent_buffer *leaf;
 949
 950	/*
 951	 * DON'T set SHAREABLE bit for log trees.
 952	 *
 953	 * Log trees are not exposed to user space thus can't be snapshotted,
 954	 * and they go away before a real commit is actually done.
 955	 *
 956	 * They do store pointers to file data extents, and those reference
 957	 * counts still get updated (along with back refs to the log tree).
 958	 */
 959
 960	leaf = btrfs_alloc_tree_block(trans, root, 0, BTRFS_TREE_LOG_OBJECTID,
 961			NULL, 0, 0, 0, 0, BTRFS_NESTING_NORMAL);
 962	if (IS_ERR(leaf))
 963		return PTR_ERR(leaf);
 964
 965	root->node = leaf;
 966
 967	btrfs_mark_buffer_dirty(trans, root->node);
 968	btrfs_tree_unlock(root->node);
 969
 970	return 0;
 971}
 972
 973int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
 974			     struct btrfs_fs_info *fs_info)
 975{
 976	struct btrfs_root *log_root;
 977
 978	log_root = alloc_log_tree(trans, fs_info);
 979	if (IS_ERR(log_root))
 980		return PTR_ERR(log_root);
 981
 982	if (!btrfs_is_zoned(fs_info)) {
 983		int ret = btrfs_alloc_log_tree_node(trans, log_root);
 984
 985		if (ret) {
 986			btrfs_put_root(log_root);
 987			return ret;
 988		}
 989	}
 990
 991	WARN_ON(fs_info->log_root_tree);
 992	fs_info->log_root_tree = log_root;
 993	return 0;
 994}
 995
 996int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
 997		       struct btrfs_root *root)
 998{
 999	struct btrfs_fs_info *fs_info = root->fs_info;
1000	struct btrfs_root *log_root;
1001	struct btrfs_inode_item *inode_item;
1002	int ret;
1003
1004	log_root = alloc_log_tree(trans, fs_info);
1005	if (IS_ERR(log_root))
1006		return PTR_ERR(log_root);
1007
1008	ret = btrfs_alloc_log_tree_node(trans, log_root);
1009	if (ret) {
1010		btrfs_put_root(log_root);
1011		return ret;
1012	}
1013
1014	log_root->last_trans = trans->transid;
1015	log_root->root_key.offset = root->root_key.objectid;
1016
1017	inode_item = &log_root->root_item.inode;
1018	btrfs_set_stack_inode_generation(inode_item, 1);
1019	btrfs_set_stack_inode_size(inode_item, 3);
1020	btrfs_set_stack_inode_nlink(inode_item, 1);
1021	btrfs_set_stack_inode_nbytes(inode_item,
1022				     fs_info->nodesize);
1023	btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
1024
1025	btrfs_set_root_node(&log_root->root_item, log_root->node);
1026
1027	WARN_ON(root->log_root);
1028	root->log_root = log_root;
1029	btrfs_set_root_log_transid(root, 0);
1030	root->log_transid_committed = -1;
1031	btrfs_set_root_last_log_commit(root, 0);
1032	return 0;
1033}
1034
1035static struct btrfs_root *read_tree_root_path(struct btrfs_root *tree_root,
1036					      struct btrfs_path *path,
1037					      struct btrfs_key *key)
1038{
1039	struct btrfs_root *root;
1040	struct btrfs_tree_parent_check check = { 0 };
1041	struct btrfs_fs_info *fs_info = tree_root->fs_info;
1042	u64 generation;
1043	int ret;
1044	int level;
1045
1046	root = btrfs_alloc_root(fs_info, key->objectid, GFP_NOFS);
1047	if (!root)
1048		return ERR_PTR(-ENOMEM);
1049
1050	ret = btrfs_find_root(tree_root, key, path,
1051			      &root->root_item, &root->root_key);
1052	if (ret) {
1053		if (ret > 0)
1054			ret = -ENOENT;
1055		goto fail;
1056	}
1057
1058	generation = btrfs_root_generation(&root->root_item);
1059	level = btrfs_root_level(&root->root_item);
1060	check.level = level;
1061	check.transid = generation;
1062	check.owner_root = key->objectid;
1063	root->node = read_tree_block(fs_info, btrfs_root_bytenr(&root->root_item),
1064				     &check);
1065	if (IS_ERR(root->node)) {
1066		ret = PTR_ERR(root->node);
1067		root->node = NULL;
1068		goto fail;
1069	}
1070	if (!btrfs_buffer_uptodate(root->node, generation, 0)) {
1071		ret = -EIO;
1072		goto fail;
1073	}
1074
1075	/*
1076	 * For real fs, and not log/reloc trees, root owner must
1077	 * match its root node owner
1078	 */
1079	if (!test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state) &&
1080	    root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID &&
1081	    root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID &&
1082	    root->root_key.objectid != btrfs_header_owner(root->node)) {
1083		btrfs_crit(fs_info,
1084"root=%llu block=%llu, tree root owner mismatch, have %llu expect %llu",
1085			   root->root_key.objectid, root->node->start,
1086			   btrfs_header_owner(root->node),
1087			   root->root_key.objectid);
1088		ret = -EUCLEAN;
1089		goto fail;
1090	}
1091	root->commit_root = btrfs_root_node(root);
1092	return root;
1093fail:
1094	btrfs_put_root(root);
1095	return ERR_PTR(ret);
1096}
1097
1098struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
1099					struct btrfs_key *key)
1100{
1101	struct btrfs_root *root;
1102	struct btrfs_path *path;
1103
1104	path = btrfs_alloc_path();
1105	if (!path)
1106		return ERR_PTR(-ENOMEM);
1107	root = read_tree_root_path(tree_root, path, key);
1108	btrfs_free_path(path);
1109
1110	return root;
1111}
1112
1113/*
1114 * Initialize subvolume root in-memory structure
1115 *
1116 * @anon_dev:	anonymous device to attach to the root, if zero, allocate new
1117 */
1118static int btrfs_init_fs_root(struct btrfs_root *root, dev_t anon_dev)
1119{
1120	int ret;
 
1121
1122	btrfs_drew_lock_init(&root->snapshot_lock);
 
 
 
 
 
 
 
 
1123
1124	if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID &&
1125	    !btrfs_is_data_reloc_root(root) &&
1126	    is_fstree(root->root_key.objectid)) {
1127		set_bit(BTRFS_ROOT_SHAREABLE, &root->state);
1128		btrfs_check_and_init_root_item(&root->root_item);
1129	}
1130
1131	/*
1132	 * Don't assign anonymous block device to roots that are not exposed to
1133	 * userspace, the id pool is limited to 1M
1134	 */
1135	if (is_fstree(root->root_key.objectid) &&
1136	    btrfs_root_refs(&root->root_item) > 0) {
1137		if (!anon_dev) {
1138			ret = get_anon_bdev(&root->anon_dev);
1139			if (ret)
1140				goto fail;
1141		} else {
1142			root->anon_dev = anon_dev;
1143		}
1144	}
1145
1146	mutex_lock(&root->objectid_mutex);
1147	ret = btrfs_init_root_free_objectid(root);
1148	if (ret) {
1149		mutex_unlock(&root->objectid_mutex);
1150		goto fail;
1151	}
1152
1153	ASSERT(root->free_objectid <= BTRFS_LAST_FREE_OBJECTID);
1154
1155	mutex_unlock(&root->objectid_mutex);
1156
1157	return 0;
1158fail:
1159	/* The caller is responsible to call btrfs_free_fs_root */
1160	return ret;
1161}
1162
1163static struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
1164					       u64 root_id)
1165{
1166	struct btrfs_root *root;
1167
1168	spin_lock(&fs_info->fs_roots_radix_lock);
1169	root = radix_tree_lookup(&fs_info->fs_roots_radix,
1170				 (unsigned long)root_id);
1171	root = btrfs_grab_root(root);
 
1172	spin_unlock(&fs_info->fs_roots_radix_lock);
1173	return root;
1174}
1175
1176static struct btrfs_root *btrfs_get_global_root(struct btrfs_fs_info *fs_info,
1177						u64 objectid)
1178{
1179	struct btrfs_key key = {
1180		.objectid = objectid,
1181		.type = BTRFS_ROOT_ITEM_KEY,
1182		.offset = 0,
1183	};
1184
1185	switch (objectid) {
1186	case BTRFS_ROOT_TREE_OBJECTID:
1187		return btrfs_grab_root(fs_info->tree_root);
1188	case BTRFS_EXTENT_TREE_OBJECTID:
1189		return btrfs_grab_root(btrfs_global_root(fs_info, &key));
1190	case BTRFS_CHUNK_TREE_OBJECTID:
1191		return btrfs_grab_root(fs_info->chunk_root);
1192	case BTRFS_DEV_TREE_OBJECTID:
1193		return btrfs_grab_root(fs_info->dev_root);
1194	case BTRFS_CSUM_TREE_OBJECTID:
1195		return btrfs_grab_root(btrfs_global_root(fs_info, &key));
1196	case BTRFS_QUOTA_TREE_OBJECTID:
1197		return btrfs_grab_root(fs_info->quota_root);
1198	case BTRFS_UUID_TREE_OBJECTID:
1199		return btrfs_grab_root(fs_info->uuid_root);
1200	case BTRFS_BLOCK_GROUP_TREE_OBJECTID:
1201		return btrfs_grab_root(fs_info->block_group_root);
1202	case BTRFS_FREE_SPACE_TREE_OBJECTID:
1203		return btrfs_grab_root(btrfs_global_root(fs_info, &key));
1204	case BTRFS_RAID_STRIPE_TREE_OBJECTID:
1205		return btrfs_grab_root(fs_info->stripe_root);
1206	default:
1207		return NULL;
 
 
 
 
 
 
 
 
 
1208	}
 
1209}
1210
1211int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
1212			 struct btrfs_root *root)
1213{
1214	int ret;
1215
1216	ret = radix_tree_preload(GFP_NOFS);
1217	if (ret)
1218		return ret;
1219
1220	spin_lock(&fs_info->fs_roots_radix_lock);
1221	ret = radix_tree_insert(&fs_info->fs_roots_radix,
1222				(unsigned long)root->root_key.objectid,
1223				root);
1224	if (ret == 0) {
1225		btrfs_grab_root(root);
1226		set_bit(BTRFS_ROOT_IN_RADIX, &root->state);
1227	}
1228	spin_unlock(&fs_info->fs_roots_radix_lock);
1229	radix_tree_preload_end();
1230
1231	return ret;
1232}
1233
1234void btrfs_check_leaked_roots(struct btrfs_fs_info *fs_info)
1235{
1236#ifdef CONFIG_BTRFS_DEBUG
1237	struct btrfs_root *root;
1238
1239	while (!list_empty(&fs_info->allocated_roots)) {
1240		char buf[BTRFS_ROOT_NAME_BUF_LEN];
1241
1242		root = list_first_entry(&fs_info->allocated_roots,
1243					struct btrfs_root, leak_list);
1244		btrfs_err(fs_info, "leaked root %s refcount %d",
1245			  btrfs_root_name(&root->root_key, buf),
1246			  refcount_read(&root->refs));
1247		while (refcount_read(&root->refs) > 1)
1248			btrfs_put_root(root);
1249		btrfs_put_root(root);
1250	}
1251#endif
1252}
1253
1254static void free_global_roots(struct btrfs_fs_info *fs_info)
1255{
1256	struct btrfs_root *root;
1257	struct rb_node *node;
1258
1259	while ((node = rb_first_postorder(&fs_info->global_root_tree)) != NULL) {
1260		root = rb_entry(node, struct btrfs_root, rb_node);
1261		rb_erase(&root->rb_node, &fs_info->global_root_tree);
1262		btrfs_put_root(root);
1263	}
1264}
1265
1266void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
1267{
1268	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
1269	percpu_counter_destroy(&fs_info->delalloc_bytes);
1270	percpu_counter_destroy(&fs_info->ordered_bytes);
1271	percpu_counter_destroy(&fs_info->dev_replace.bio_counter);
1272	btrfs_free_csum_hash(fs_info);
1273	btrfs_free_stripe_hash_table(fs_info);
1274	btrfs_free_ref_cache(fs_info);
1275	kfree(fs_info->balance_ctl);
1276	kfree(fs_info->delayed_root);
1277	free_global_roots(fs_info);
1278	btrfs_put_root(fs_info->tree_root);
1279	btrfs_put_root(fs_info->chunk_root);
1280	btrfs_put_root(fs_info->dev_root);
1281	btrfs_put_root(fs_info->quota_root);
1282	btrfs_put_root(fs_info->uuid_root);
1283	btrfs_put_root(fs_info->fs_root);
1284	btrfs_put_root(fs_info->data_reloc_root);
1285	btrfs_put_root(fs_info->block_group_root);
1286	btrfs_put_root(fs_info->stripe_root);
1287	btrfs_check_leaked_roots(fs_info);
1288	btrfs_extent_buffer_leak_debug_check(fs_info);
1289	kfree(fs_info->super_copy);
1290	kfree(fs_info->super_for_commit);
1291	kfree(fs_info->subpage_info);
1292	kvfree(fs_info);
1293}
1294
1295
1296/*
1297 * Get an in-memory reference of a root structure.
1298 *
1299 * For essential trees like root/extent tree, we grab it from fs_info directly.
1300 * For subvolume trees, we check the cached filesystem roots first. If not
1301 * found, then read it from disk and add it to cached fs roots.
1302 *
1303 * Caller should release the root by calling btrfs_put_root() after the usage.
1304 *
1305 * NOTE: Reloc and log trees can't be read by this function as they share the
1306 *	 same root objectid.
1307 *
1308 * @objectid:	root id
1309 * @anon_dev:	preallocated anonymous block device number for new roots,
1310 *		pass NULL for a new allocation.
1311 * @check_ref:	whether to check root item references, If true, return -ENOENT
1312 *		for orphan roots
1313 */
1314static struct btrfs_root *btrfs_get_root_ref(struct btrfs_fs_info *fs_info,
1315					     u64 objectid, dev_t *anon_dev,
1316					     bool check_ref)
1317{
1318	struct btrfs_root *root;
1319	struct btrfs_path *path;
1320	struct btrfs_key key;
1321	int ret;
1322
1323	root = btrfs_get_global_root(fs_info, objectid);
1324	if (root)
1325		return root;
1326
1327	/*
1328	 * If we're called for non-subvolume trees, and above function didn't
1329	 * find one, do not try to read it from disk.
1330	 *
1331	 * This is namely for free-space-tree and quota tree, which can change
1332	 * at runtime and should only be grabbed from fs_info.
1333	 */
1334	if (!is_fstree(objectid) && objectid != BTRFS_DATA_RELOC_TREE_OBJECTID)
1335		return ERR_PTR(-ENOENT);
1336again:
1337	root = btrfs_lookup_fs_root(fs_info, objectid);
1338	if (root) {
1339		/*
1340		 * Some other caller may have read out the newly inserted
1341		 * subvolume already (for things like backref walk etc).  Not
1342		 * that common but still possible.  In that case, we just need
1343		 * to free the anon_dev.
1344		 */
1345		if (unlikely(anon_dev && *anon_dev)) {
1346			free_anon_bdev(*anon_dev);
1347			*anon_dev = 0;
1348		}
1349
1350		if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1351			btrfs_put_root(root);
1352			return ERR_PTR(-ENOENT);
1353		}
1354		return root;
1355	}
1356
1357	key.objectid = objectid;
1358	key.type = BTRFS_ROOT_ITEM_KEY;
1359	key.offset = (u64)-1;
1360	root = btrfs_read_tree_root(fs_info->tree_root, &key);
1361	if (IS_ERR(root))
1362		return root;
1363
1364	if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1365		ret = -ENOENT;
1366		goto fail;
1367	}
1368
1369	ret = btrfs_init_fs_root(root, anon_dev ? *anon_dev : 0);
1370	if (ret)
1371		goto fail;
1372
1373	path = btrfs_alloc_path();
1374	if (!path) {
1375		ret = -ENOMEM;
1376		goto fail;
1377	}
1378	key.objectid = BTRFS_ORPHAN_OBJECTID;
1379	key.type = BTRFS_ORPHAN_ITEM_KEY;
1380	key.offset = objectid;
1381
1382	ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
1383	btrfs_free_path(path);
1384	if (ret < 0)
1385		goto fail;
1386	if (ret == 0)
1387		set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state);
1388
1389	ret = btrfs_insert_fs_root(fs_info, root);
1390	if (ret) {
1391		if (ret == -EEXIST) {
1392			btrfs_put_root(root);
1393			goto again;
1394		}
1395		goto fail;
1396	}
1397	return root;
1398fail:
1399	/*
1400	 * If our caller provided us an anonymous device, then it's his
1401	 * responsibility to free it in case we fail. So we have to set our
1402	 * root's anon_dev to 0 to avoid a double free, once by btrfs_put_root()
1403	 * and once again by our caller.
1404	 */
1405	if (anon_dev && *anon_dev)
1406		root->anon_dev = 0;
1407	btrfs_put_root(root);
1408	return ERR_PTR(ret);
1409}
1410
1411/*
1412 * Get in-memory reference of a root structure
1413 *
1414 * @objectid:	tree objectid
1415 * @check_ref:	if set, verify that the tree exists and the item has at least
1416 *		one reference
1417 */
1418struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
1419				     u64 objectid, bool check_ref)
1420{
1421	return btrfs_get_root_ref(fs_info, objectid, NULL, check_ref);
1422}
1423
1424/*
1425 * Get in-memory reference of a root structure, created as new, optionally pass
1426 * the anonymous block device id
1427 *
1428 * @objectid:	tree objectid
1429 * @anon_dev:	if NULL, allocate a new anonymous block device or use the
1430 *		parameter value if not NULL
1431 */
1432struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
1433					 u64 objectid, dev_t *anon_dev)
1434{
1435	return btrfs_get_root_ref(fs_info, objectid, anon_dev, true);
1436}
1437
1438/*
1439 * Return a root for the given objectid.
1440 *
1441 * @fs_info:	the fs_info
1442 * @objectid:	the objectid we need to lookup
1443 *
1444 * This is exclusively used for backref walking, and exists specifically because
1445 * of how qgroups does lookups.  Qgroups will do a backref lookup at delayed ref
1446 * creation time, which means we may have to read the tree_root in order to look
1447 * up a fs root that is not in memory.  If the root is not in memory we will
1448 * read the tree root commit root and look up the fs root from there.  This is a
1449 * temporary root, it will not be inserted into the radix tree as it doesn't
1450 * have the most uptodate information, it'll simply be discarded once the
1451 * backref code is finished using the root.
1452 */
1453struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
1454						 struct btrfs_path *path,
1455						 u64 objectid)
1456{
1457	struct btrfs_root *root;
1458	struct btrfs_key key;
1459
1460	ASSERT(path->search_commit_root && path->skip_locking);
1461
1462	/*
1463	 * This can return -ENOENT if we ask for a root that doesn't exist, but
1464	 * since this is called via the backref walking code we won't be looking
1465	 * up a root that doesn't exist, unless there's corruption.  So if root
1466	 * != NULL just return it.
1467	 */
1468	root = btrfs_get_global_root(fs_info, objectid);
1469	if (root)
1470		return root;
1471
1472	root = btrfs_lookup_fs_root(fs_info, objectid);
1473	if (root)
1474		return root;
1475
1476	key.objectid = objectid;
1477	key.type = BTRFS_ROOT_ITEM_KEY;
1478	key.offset = (u64)-1;
1479	root = read_tree_root_path(fs_info->tree_root, path, &key);
1480	btrfs_release_path(path);
1481
1482	return root;
1483}
1484
1485static int cleaner_kthread(void *arg)
1486{
1487	struct btrfs_fs_info *fs_info = arg;
1488	int again;
1489
1490	while (1) {
1491		again = 0;
1492
1493		set_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1494
1495		/* Make the cleaner go to sleep early. */
1496		if (btrfs_need_cleaner_sleep(fs_info))
1497			goto sleep;
1498
1499		/*
1500		 * Do not do anything if we might cause open_ctree() to block
1501		 * before we have finished mounting the filesystem.
1502		 */
1503		if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags))
1504			goto sleep;
1505
1506		if (!mutex_trylock(&fs_info->cleaner_mutex))
1507			goto sleep;
1508
1509		/*
1510		 * Avoid the problem that we change the status of the fs
1511		 * during the above check and trylock.
1512		 */
1513		if (btrfs_need_cleaner_sleep(fs_info)) {
1514			mutex_unlock(&fs_info->cleaner_mutex);
1515			goto sleep;
1516		}
1517
1518		if (test_and_clear_bit(BTRFS_FS_FEATURE_CHANGED, &fs_info->flags))
1519			btrfs_sysfs_feature_update(fs_info);
1520
1521		btrfs_run_delayed_iputs(fs_info);
1522
1523		again = btrfs_clean_one_deleted_snapshot(fs_info);
1524		mutex_unlock(&fs_info->cleaner_mutex);
1525
1526		/*
1527		 * The defragger has dealt with the R/O remount and umount,
1528		 * needn't do anything special here.
1529		 */
1530		btrfs_run_defrag_inodes(fs_info);
1531
1532		/*
1533		 * Acquires fs_info->reclaim_bgs_lock to avoid racing
1534		 * with relocation (btrfs_relocate_chunk) and relocation
1535		 * acquires fs_info->cleaner_mutex (btrfs_relocate_block_group)
1536		 * after acquiring fs_info->reclaim_bgs_lock. So we
1537		 * can't hold, nor need to, fs_info->cleaner_mutex when deleting
1538		 * unused block groups.
1539		 */
1540		btrfs_delete_unused_bgs(fs_info);
1541
1542		/*
1543		 * Reclaim block groups in the reclaim_bgs list after we deleted
1544		 * all unused block_groups. This possibly gives us some more free
1545		 * space.
1546		 */
1547		btrfs_reclaim_bgs(fs_info);
1548sleep:
1549		clear_and_wake_up_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1550		if (kthread_should_park())
1551			kthread_parkme();
1552		if (kthread_should_stop())
1553			return 0;
1554		if (!again) {
1555			set_current_state(TASK_INTERRUPTIBLE);
1556			schedule();
1557			__set_current_state(TASK_RUNNING);
1558		}
1559	}
1560}
1561
1562static int transaction_kthread(void *arg)
1563{
1564	struct btrfs_root *root = arg;
1565	struct btrfs_fs_info *fs_info = root->fs_info;
1566	struct btrfs_trans_handle *trans;
1567	struct btrfs_transaction *cur;
1568	u64 transid;
1569	time64_t delta;
1570	unsigned long delay;
1571	bool cannot_commit;
1572
1573	do {
1574		cannot_commit = false;
1575		delay = msecs_to_jiffies(fs_info->commit_interval * 1000);
1576		mutex_lock(&fs_info->transaction_kthread_mutex);
1577
1578		spin_lock(&fs_info->trans_lock);
1579		cur = fs_info->running_transaction;
1580		if (!cur) {
1581			spin_unlock(&fs_info->trans_lock);
1582			goto sleep;
1583		}
1584
1585		delta = ktime_get_seconds() - cur->start_time;
1586		if (!test_and_clear_bit(BTRFS_FS_COMMIT_TRANS, &fs_info->flags) &&
1587		    cur->state < TRANS_STATE_COMMIT_PREP &&
1588		    delta < fs_info->commit_interval) {
1589			spin_unlock(&fs_info->trans_lock);
1590			delay -= msecs_to_jiffies((delta - 1) * 1000);
1591			delay = min(delay,
1592				    msecs_to_jiffies(fs_info->commit_interval * 1000));
1593			goto sleep;
1594		}
1595		transid = cur->transid;
1596		spin_unlock(&fs_info->trans_lock);
1597
1598		/* If the file system is aborted, this will always fail. */
1599		trans = btrfs_attach_transaction(root);
1600		if (IS_ERR(trans)) {
1601			if (PTR_ERR(trans) != -ENOENT)
1602				cannot_commit = true;
1603			goto sleep;
1604		}
1605		if (transid == trans->transid) {
1606			btrfs_commit_transaction(trans);
1607		} else {
1608			btrfs_end_transaction(trans);
1609		}
1610sleep:
1611		wake_up_process(fs_info->cleaner_kthread);
1612		mutex_unlock(&fs_info->transaction_kthread_mutex);
1613
1614		if (BTRFS_FS_ERROR(fs_info))
1615			btrfs_cleanup_transaction(fs_info);
1616		if (!kthread_should_stop() &&
1617				(!btrfs_transaction_blocked(fs_info) ||
1618				 cannot_commit))
1619			schedule_timeout_interruptible(delay);
1620	} while (!kthread_should_stop());
1621	return 0;
1622}
1623
1624/*
1625 * This will find the highest generation in the array of root backups.  The
1626 * index of the highest array is returned, or -EINVAL if we can't find
1627 * anything.
1628 *
1629 * We check to make sure the array is valid by comparing the
1630 * generation of the latest  root in the array with the generation
1631 * in the super block.  If they don't match we pitch it.
1632 */
1633static int find_newest_super_backup(struct btrfs_fs_info *info)
1634{
1635	const u64 newest_gen = btrfs_super_generation(info->super_copy);
1636	u64 cur;
1637	struct btrfs_root_backup *root_backup;
1638	int i;
1639
1640	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
1641		root_backup = info->super_copy->super_roots + i;
1642		cur = btrfs_backup_tree_root_gen(root_backup);
1643		if (cur == newest_gen)
1644			return i;
1645	}
1646
1647	return -EINVAL;
1648}
1649
1650/*
1651 * copy all the root pointers into the super backup array.
1652 * this will bump the backup pointer by one when it is
1653 * done
1654 */
1655static void backup_super_roots(struct btrfs_fs_info *info)
1656{
1657	const int next_backup = info->backup_root_index;
1658	struct btrfs_root_backup *root_backup;
1659
1660	root_backup = info->super_for_commit->super_roots + next_backup;
1661
1662	/*
1663	 * make sure all of our padding and empty slots get zero filled
1664	 * regardless of which ones we use today
1665	 */
1666	memset(root_backup, 0, sizeof(*root_backup));
1667
1668	info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
1669
1670	btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
1671	btrfs_set_backup_tree_root_gen(root_backup,
1672			       btrfs_header_generation(info->tree_root->node));
1673
1674	btrfs_set_backup_tree_root_level(root_backup,
1675			       btrfs_header_level(info->tree_root->node));
1676
1677	btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
1678	btrfs_set_backup_chunk_root_gen(root_backup,
1679			       btrfs_header_generation(info->chunk_root->node));
1680	btrfs_set_backup_chunk_root_level(root_backup,
1681			       btrfs_header_level(info->chunk_root->node));
1682
1683	if (!btrfs_fs_compat_ro(info, BLOCK_GROUP_TREE)) {
1684		struct btrfs_root *extent_root = btrfs_extent_root(info, 0);
1685		struct btrfs_root *csum_root = btrfs_csum_root(info, 0);
1686
1687		btrfs_set_backup_extent_root(root_backup,
1688					     extent_root->node->start);
1689		btrfs_set_backup_extent_root_gen(root_backup,
1690				btrfs_header_generation(extent_root->node));
1691		btrfs_set_backup_extent_root_level(root_backup,
1692					btrfs_header_level(extent_root->node));
1693
1694		btrfs_set_backup_csum_root(root_backup, csum_root->node->start);
1695		btrfs_set_backup_csum_root_gen(root_backup,
1696					       btrfs_header_generation(csum_root->node));
1697		btrfs_set_backup_csum_root_level(root_backup,
1698						 btrfs_header_level(csum_root->node));
1699	}
1700
1701	/*
1702	 * we might commit during log recovery, which happens before we set
1703	 * the fs_root.  Make sure it is valid before we fill it in.
1704	 */
1705	if (info->fs_root && info->fs_root->node) {
1706		btrfs_set_backup_fs_root(root_backup,
1707					 info->fs_root->node->start);
1708		btrfs_set_backup_fs_root_gen(root_backup,
1709			       btrfs_header_generation(info->fs_root->node));
1710		btrfs_set_backup_fs_root_level(root_backup,
1711			       btrfs_header_level(info->fs_root->node));
1712	}
1713
1714	btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
1715	btrfs_set_backup_dev_root_gen(root_backup,
1716			       btrfs_header_generation(info->dev_root->node));
1717	btrfs_set_backup_dev_root_level(root_backup,
1718				       btrfs_header_level(info->dev_root->node));
1719
1720	btrfs_set_backup_total_bytes(root_backup,
1721			     btrfs_super_total_bytes(info->super_copy));
1722	btrfs_set_backup_bytes_used(root_backup,
1723			     btrfs_super_bytes_used(info->super_copy));
1724	btrfs_set_backup_num_devices(root_backup,
1725			     btrfs_super_num_devices(info->super_copy));
1726
1727	/*
1728	 * if we don't copy this out to the super_copy, it won't get remembered
1729	 * for the next commit
1730	 */
1731	memcpy(&info->super_copy->super_roots,
1732	       &info->super_for_commit->super_roots,
1733	       sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
1734}
1735
1736/*
1737 * Reads a backup root based on the passed priority. Prio 0 is the newest, prio
1738 * 1/2/3 are 2nd newest/3rd newest/4th (oldest) backup roots
1739 *
1740 * @fs_info:  filesystem whose backup roots need to be read
1741 * @priority: priority of backup root required
1742 *
1743 * Returns backup root index on success and -EINVAL otherwise.
1744 */
1745static int read_backup_root(struct btrfs_fs_info *fs_info, u8 priority)
1746{
1747	int backup_index = find_newest_super_backup(fs_info);
1748	struct btrfs_super_block *super = fs_info->super_copy;
1749	struct btrfs_root_backup *root_backup;
1750
1751	if (priority < BTRFS_NUM_BACKUP_ROOTS && backup_index >= 0) {
1752		if (priority == 0)
1753			return backup_index;
1754
1755		backup_index = backup_index + BTRFS_NUM_BACKUP_ROOTS - priority;
1756		backup_index %= BTRFS_NUM_BACKUP_ROOTS;
1757	} else {
1758		return -EINVAL;
1759	}
1760
1761	root_backup = super->super_roots + backup_index;
1762
1763	btrfs_set_super_generation(super,
1764				   btrfs_backup_tree_root_gen(root_backup));
1765	btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
1766	btrfs_set_super_root_level(super,
1767				   btrfs_backup_tree_root_level(root_backup));
1768	btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
1769
1770	/*
1771	 * Fixme: the total bytes and num_devices need to match or we should
1772	 * need a fsck
1773	 */
1774	btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
1775	btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
1776
1777	return backup_index;
1778}
1779
1780/* helper to cleanup workers */
1781static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
1782{
1783	btrfs_destroy_workqueue(fs_info->fixup_workers);
1784	btrfs_destroy_workqueue(fs_info->delalloc_workers);
 
1785	btrfs_destroy_workqueue(fs_info->workers);
1786	if (fs_info->endio_workers)
1787		destroy_workqueue(fs_info->endio_workers);
1788	if (fs_info->rmw_workers)
1789		destroy_workqueue(fs_info->rmw_workers);
1790	if (fs_info->compressed_write_workers)
1791		destroy_workqueue(fs_info->compressed_write_workers);
1792	btrfs_destroy_workqueue(fs_info->endio_write_workers);
1793	btrfs_destroy_workqueue(fs_info->endio_freespace_worker);
1794	btrfs_destroy_workqueue(fs_info->delayed_workers);
1795	btrfs_destroy_workqueue(fs_info->caching_workers);
1796	btrfs_destroy_workqueue(fs_info->flush_workers);
1797	btrfs_destroy_workqueue(fs_info->qgroup_rescan_workers);
1798	if (fs_info->discard_ctl.discard_workers)
1799		destroy_workqueue(fs_info->discard_ctl.discard_workers);
1800	/*
1801	 * Now that all other work queues are destroyed, we can safely destroy
1802	 * the queues used for metadata I/O, since tasks from those other work
1803	 * queues can do metadata I/O operations.
1804	 */
1805	if (fs_info->endio_meta_workers)
1806		destroy_workqueue(fs_info->endio_meta_workers);
1807}
1808
1809static void free_root_extent_buffers(struct btrfs_root *root)
1810{
1811	if (root) {
1812		free_extent_buffer(root->node);
1813		free_extent_buffer(root->commit_root);
1814		root->node = NULL;
1815		root->commit_root = NULL;
1816	}
1817}
1818
1819static void free_global_root_pointers(struct btrfs_fs_info *fs_info)
1820{
1821	struct btrfs_root *root, *tmp;
1822
1823	rbtree_postorder_for_each_entry_safe(root, tmp,
1824					     &fs_info->global_root_tree,
1825					     rb_node)
1826		free_root_extent_buffers(root);
1827}
1828
1829/* helper to cleanup tree roots */
1830static void free_root_pointers(struct btrfs_fs_info *info, bool free_chunk_root)
1831{
1832	free_root_extent_buffers(info->tree_root);
1833
1834	free_global_root_pointers(info);
1835	free_root_extent_buffers(info->dev_root);
1836	free_root_extent_buffers(info->quota_root);
1837	free_root_extent_buffers(info->uuid_root);
1838	free_root_extent_buffers(info->fs_root);
1839	free_root_extent_buffers(info->data_reloc_root);
1840	free_root_extent_buffers(info->block_group_root);
1841	free_root_extent_buffers(info->stripe_root);
1842	if (free_chunk_root)
1843		free_root_extent_buffers(info->chunk_root);
1844}
1845
1846void btrfs_put_root(struct btrfs_root *root)
1847{
1848	if (!root)
1849		return;
1850
1851	if (refcount_dec_and_test(&root->refs)) {
1852		WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
1853		WARN_ON(test_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state));
1854		if (root->anon_dev)
1855			free_anon_bdev(root->anon_dev);
 
1856		free_root_extent_buffers(root);
1857#ifdef CONFIG_BTRFS_DEBUG
1858		spin_lock(&root->fs_info->fs_roots_radix_lock);
1859		list_del_init(&root->leak_list);
1860		spin_unlock(&root->fs_info->fs_roots_radix_lock);
1861#endif
1862		kfree(root);
1863	}
1864}
1865
1866void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info)
1867{
1868	int ret;
1869	struct btrfs_root *gang[8];
1870	int i;
1871
1872	while (!list_empty(&fs_info->dead_roots)) {
1873		gang[0] = list_entry(fs_info->dead_roots.next,
1874				     struct btrfs_root, root_list);
1875		list_del(&gang[0]->root_list);
1876
1877		if (test_bit(BTRFS_ROOT_IN_RADIX, &gang[0]->state))
1878			btrfs_drop_and_free_fs_root(fs_info, gang[0]);
1879		btrfs_put_root(gang[0]);
1880	}
1881
1882	while (1) {
1883		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
1884					     (void **)gang, 0,
1885					     ARRAY_SIZE(gang));
1886		if (!ret)
1887			break;
1888		for (i = 0; i < ret; i++)
1889			btrfs_drop_and_free_fs_root(fs_info, gang[i]);
1890	}
1891}
1892
1893static void btrfs_init_scrub(struct btrfs_fs_info *fs_info)
1894{
1895	mutex_init(&fs_info->scrub_lock);
1896	atomic_set(&fs_info->scrubs_running, 0);
1897	atomic_set(&fs_info->scrub_pause_req, 0);
1898	atomic_set(&fs_info->scrubs_paused, 0);
1899	atomic_set(&fs_info->scrub_cancel_req, 0);
1900	init_waitqueue_head(&fs_info->scrub_pause_wait);
1901	refcount_set(&fs_info->scrub_workers_refcnt, 0);
1902}
1903
1904static void btrfs_init_balance(struct btrfs_fs_info *fs_info)
1905{
1906	spin_lock_init(&fs_info->balance_lock);
1907	mutex_init(&fs_info->balance_mutex);
1908	atomic_set(&fs_info->balance_pause_req, 0);
1909	atomic_set(&fs_info->balance_cancel_req, 0);
1910	fs_info->balance_ctl = NULL;
1911	init_waitqueue_head(&fs_info->balance_wait_q);
1912	atomic_set(&fs_info->reloc_cancel_req, 0);
1913}
1914
1915static int btrfs_init_btree_inode(struct super_block *sb)
1916{
1917	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
1918	unsigned long hash = btrfs_inode_hash(BTRFS_BTREE_INODE_OBJECTID,
1919					      fs_info->tree_root);
1920	struct inode *inode;
1921
1922	inode = new_inode(sb);
1923	if (!inode)
1924		return -ENOMEM;
1925
1926	inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
1927	set_nlink(inode, 1);
1928	/*
1929	 * we set the i_size on the btree inode to the max possible int.
1930	 * the real end of the address space is determined by all of
1931	 * the devices in the system
1932	 */
1933	inode->i_size = OFFSET_MAX;
1934	inode->i_mapping->a_ops = &btree_aops;
1935	mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
1936
1937	RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
1938	extent_io_tree_init(fs_info, &BTRFS_I(inode)->io_tree,
1939			    IO_TREE_BTREE_INODE_IO);
1940	extent_map_tree_init(&BTRFS_I(inode)->extent_tree);
1941
1942	BTRFS_I(inode)->root = btrfs_grab_root(fs_info->tree_root);
1943	BTRFS_I(inode)->location.objectid = BTRFS_BTREE_INODE_OBJECTID;
1944	BTRFS_I(inode)->location.type = 0;
1945	BTRFS_I(inode)->location.offset = 0;
1946	set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
1947	__insert_inode_hash(inode, hash);
1948	fs_info->btree_inode = inode;
1949
1950	return 0;
1951}
1952
1953static void btrfs_init_dev_replace_locks(struct btrfs_fs_info *fs_info)
1954{
1955	mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount);
1956	init_rwsem(&fs_info->dev_replace.rwsem);
1957	init_waitqueue_head(&fs_info->dev_replace.replace_wait);
1958}
1959
1960static void btrfs_init_qgroup(struct btrfs_fs_info *fs_info)
1961{
1962	spin_lock_init(&fs_info->qgroup_lock);
1963	mutex_init(&fs_info->qgroup_ioctl_lock);
1964	fs_info->qgroup_tree = RB_ROOT;
1965	INIT_LIST_HEAD(&fs_info->dirty_qgroups);
1966	fs_info->qgroup_seq = 1;
1967	fs_info->qgroup_ulist = NULL;
1968	fs_info->qgroup_rescan_running = false;
1969	fs_info->qgroup_drop_subtree_thres = BTRFS_MAX_LEVEL;
1970	mutex_init(&fs_info->qgroup_rescan_lock);
1971}
1972
1973static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info)
1974{
1975	u32 max_active = fs_info->thread_pool_size;
1976	unsigned int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND;
1977	unsigned int ordered_flags = WQ_MEM_RECLAIM | WQ_FREEZABLE;
1978
1979	fs_info->workers =
1980		btrfs_alloc_workqueue(fs_info, "worker", flags, max_active, 16);
 
 
 
1981
1982	fs_info->delalloc_workers =
1983		btrfs_alloc_workqueue(fs_info, "delalloc",
1984				      flags, max_active, 2);
1985
1986	fs_info->flush_workers =
1987		btrfs_alloc_workqueue(fs_info, "flush_delalloc",
1988				      flags, max_active, 0);
1989
1990	fs_info->caching_workers =
1991		btrfs_alloc_workqueue(fs_info, "cache", flags, max_active, 0);
1992
1993	fs_info->fixup_workers =
1994		btrfs_alloc_ordered_workqueue(fs_info, "fixup", ordered_flags);
1995
1996	fs_info->endio_workers =
1997		alloc_workqueue("btrfs-endio", flags, max_active);
1998	fs_info->endio_meta_workers =
1999		alloc_workqueue("btrfs-endio-meta", flags, max_active);
2000	fs_info->rmw_workers = alloc_workqueue("btrfs-rmw", flags, max_active);
2001	fs_info->endio_write_workers =
2002		btrfs_alloc_workqueue(fs_info, "endio-write", flags,
2003				      max_active, 2);
2004	fs_info->compressed_write_workers =
2005		alloc_workqueue("btrfs-compressed-write", flags, max_active);
2006	fs_info->endio_freespace_worker =
2007		btrfs_alloc_workqueue(fs_info, "freespace-write", flags,
2008				      max_active, 0);
2009	fs_info->delayed_workers =
2010		btrfs_alloc_workqueue(fs_info, "delayed-meta", flags,
2011				      max_active, 0);
2012	fs_info->qgroup_rescan_workers =
2013		btrfs_alloc_ordered_workqueue(fs_info, "qgroup-rescan",
2014					      ordered_flags);
2015	fs_info->discard_ctl.discard_workers =
2016		alloc_ordered_workqueue("btrfs_discard", WQ_FREEZABLE);
2017
2018	if (!(fs_info->workers &&
2019	      fs_info->delalloc_workers && fs_info->flush_workers &&
2020	      fs_info->endio_workers && fs_info->endio_meta_workers &&
2021	      fs_info->compressed_write_workers &&
2022	      fs_info->endio_write_workers &&
2023	      fs_info->endio_freespace_worker && fs_info->rmw_workers &&
2024	      fs_info->caching_workers && fs_info->fixup_workers &&
2025	      fs_info->delayed_workers && fs_info->qgroup_rescan_workers &&
2026	      fs_info->discard_ctl.discard_workers)) {
2027		return -ENOMEM;
2028	}
2029
2030	return 0;
2031}
2032
2033static int btrfs_init_csum_hash(struct btrfs_fs_info *fs_info, u16 csum_type)
2034{
2035	struct crypto_shash *csum_shash;
2036	const char *csum_driver = btrfs_super_csum_driver(csum_type);
2037
2038	csum_shash = crypto_alloc_shash(csum_driver, 0, 0);
2039
2040	if (IS_ERR(csum_shash)) {
2041		btrfs_err(fs_info, "error allocating %s hash for checksum",
2042			  csum_driver);
2043		return PTR_ERR(csum_shash);
2044	}
2045
2046	fs_info->csum_shash = csum_shash;
2047
2048	/*
2049	 * Check if the checksum implementation is a fast accelerated one.
2050	 * As-is this is a bit of a hack and should be replaced once the csum
2051	 * implementations provide that information themselves.
2052	 */
2053	switch (csum_type) {
2054	case BTRFS_CSUM_TYPE_CRC32:
2055		if (!strstr(crypto_shash_driver_name(csum_shash), "generic"))
2056			set_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags);
2057		break;
2058	case BTRFS_CSUM_TYPE_XXHASH:
2059		set_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags);
2060		break;
2061	default:
2062		break;
2063	}
2064
2065	btrfs_info(fs_info, "using %s (%s) checksum algorithm",
2066			btrfs_super_csum_name(csum_type),
2067			crypto_shash_driver_name(csum_shash));
2068	return 0;
2069}
2070
2071static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
2072			    struct btrfs_fs_devices *fs_devices)
2073{
2074	int ret;
2075	struct btrfs_tree_parent_check check = { 0 };
2076	struct btrfs_root *log_tree_root;
2077	struct btrfs_super_block *disk_super = fs_info->super_copy;
2078	u64 bytenr = btrfs_super_log_root(disk_super);
2079	int level = btrfs_super_log_root_level(disk_super);
2080
2081	if (fs_devices->rw_devices == 0) {
2082		btrfs_warn(fs_info, "log replay required on RO media");
2083		return -EIO;
2084	}
2085
2086	log_tree_root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID,
2087					 GFP_KERNEL);
2088	if (!log_tree_root)
2089		return -ENOMEM;
2090
2091	check.level = level;
2092	check.transid = fs_info->generation + 1;
2093	check.owner_root = BTRFS_TREE_LOG_OBJECTID;
2094	log_tree_root->node = read_tree_block(fs_info, bytenr, &check);
2095	if (IS_ERR(log_tree_root->node)) {
2096		btrfs_warn(fs_info, "failed to read log tree");
2097		ret = PTR_ERR(log_tree_root->node);
2098		log_tree_root->node = NULL;
2099		btrfs_put_root(log_tree_root);
2100		return ret;
2101	}
2102	if (!extent_buffer_uptodate(log_tree_root->node)) {
2103		btrfs_err(fs_info, "failed to read log tree");
2104		btrfs_put_root(log_tree_root);
2105		return -EIO;
2106	}
2107
2108	/* returns with log_tree_root freed on success */
2109	ret = btrfs_recover_log_trees(log_tree_root);
2110	if (ret) {
2111		btrfs_handle_fs_error(fs_info, ret,
2112				      "Failed to recover log tree");
2113		btrfs_put_root(log_tree_root);
2114		return ret;
2115	}
2116
2117	if (sb_rdonly(fs_info->sb)) {
2118		ret = btrfs_commit_super(fs_info);
2119		if (ret)
2120			return ret;
2121	}
2122
2123	return 0;
2124}
2125
2126static int load_global_roots_objectid(struct btrfs_root *tree_root,
2127				      struct btrfs_path *path, u64 objectid,
2128				      const char *name)
2129{
2130	struct btrfs_fs_info *fs_info = tree_root->fs_info;
2131	struct btrfs_root *root;
2132	u64 max_global_id = 0;
2133	int ret;
2134	struct btrfs_key key = {
2135		.objectid = objectid,
2136		.type = BTRFS_ROOT_ITEM_KEY,
2137		.offset = 0,
2138	};
2139	bool found = false;
2140
2141	/* If we have IGNOREDATACSUMS skip loading these roots. */
2142	if (objectid == BTRFS_CSUM_TREE_OBJECTID &&
2143	    btrfs_test_opt(fs_info, IGNOREDATACSUMS)) {
2144		set_bit(BTRFS_FS_STATE_NO_CSUMS, &fs_info->fs_state);
2145		return 0;
2146	}
2147
2148	while (1) {
2149		ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0);
2150		if (ret < 0)
2151			break;
2152
2153		if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
2154			ret = btrfs_next_leaf(tree_root, path);
2155			if (ret) {
2156				if (ret > 0)
2157					ret = 0;
2158				break;
2159			}
2160		}
2161		ret = 0;
2162
2163		btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
2164		if (key.objectid != objectid)
2165			break;
2166		btrfs_release_path(path);
2167
2168		/*
2169		 * Just worry about this for extent tree, it'll be the same for
2170		 * everybody.
2171		 */
2172		if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
2173			max_global_id = max(max_global_id, key.offset);
2174
2175		found = true;
2176		root = read_tree_root_path(tree_root, path, &key);
2177		if (IS_ERR(root)) {
2178			if (!btrfs_test_opt(fs_info, IGNOREBADROOTS))
2179				ret = PTR_ERR(root);
2180			break;
2181		}
2182		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2183		ret = btrfs_global_root_insert(root);
2184		if (ret) {
2185			btrfs_put_root(root);
2186			break;
2187		}
2188		key.offset++;
2189	}
2190	btrfs_release_path(path);
2191
2192	if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
2193		fs_info->nr_global_roots = max_global_id + 1;
2194
2195	if (!found || ret) {
2196		if (objectid == BTRFS_CSUM_TREE_OBJECTID)
2197			set_bit(BTRFS_FS_STATE_NO_CSUMS, &fs_info->fs_state);
2198
2199		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS))
2200			ret = ret ? ret : -ENOENT;
2201		else
2202			ret = 0;
2203		btrfs_err(fs_info, "failed to load root %s", name);
2204	}
2205	return ret;
2206}
2207
2208static int load_global_roots(struct btrfs_root *tree_root)
2209{
2210	struct btrfs_path *path;
2211	int ret = 0;
2212
2213	path = btrfs_alloc_path();
2214	if (!path)
2215		return -ENOMEM;
2216
2217	ret = load_global_roots_objectid(tree_root, path,
2218					 BTRFS_EXTENT_TREE_OBJECTID, "extent");
2219	if (ret)
2220		goto out;
2221	ret = load_global_roots_objectid(tree_root, path,
2222					 BTRFS_CSUM_TREE_OBJECTID, "csum");
2223	if (ret)
2224		goto out;
2225	if (!btrfs_fs_compat_ro(tree_root->fs_info, FREE_SPACE_TREE))
2226		goto out;
2227	ret = load_global_roots_objectid(tree_root, path,
2228					 BTRFS_FREE_SPACE_TREE_OBJECTID,
2229					 "free space");
2230out:
2231	btrfs_free_path(path);
2232	return ret;
2233}
2234
2235static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
2236{
2237	struct btrfs_root *tree_root = fs_info->tree_root;
2238	struct btrfs_root *root;
2239	struct btrfs_key location;
2240	int ret;
2241
2242	BUG_ON(!fs_info->tree_root);
2243
2244	ret = load_global_roots(tree_root);
2245	if (ret)
2246		return ret;
2247
2248	location.type = BTRFS_ROOT_ITEM_KEY;
2249	location.offset = 0;
2250
2251	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE)) {
2252		location.objectid = BTRFS_BLOCK_GROUP_TREE_OBJECTID;
2253		root = btrfs_read_tree_root(tree_root, &location);
2254		if (IS_ERR(root)) {
2255			if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2256				ret = PTR_ERR(root);
2257				goto out;
2258			}
2259		} else {
2260			set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2261			fs_info->block_group_root = root;
2262		}
2263	}
2264
2265	location.objectid = BTRFS_DEV_TREE_OBJECTID;
2266	root = btrfs_read_tree_root(tree_root, &location);
2267	if (IS_ERR(root)) {
2268		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2269			ret = PTR_ERR(root);
2270			goto out;
2271		}
2272	} else {
2273		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2274		fs_info->dev_root = root;
2275	}
2276	/* Initialize fs_info for all devices in any case */
2277	ret = btrfs_init_devices_late(fs_info);
2278	if (ret)
2279		goto out;
2280
2281	/*
2282	 * This tree can share blocks with some other fs tree during relocation
2283	 * and we need a proper setup by btrfs_get_fs_root
2284	 */
2285	root = btrfs_get_fs_root(tree_root->fs_info,
2286				 BTRFS_DATA_RELOC_TREE_OBJECTID, true);
2287	if (IS_ERR(root)) {
2288		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2289			ret = PTR_ERR(root);
2290			goto out;
2291		}
2292	} else {
2293		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2294		fs_info->data_reloc_root = root;
2295	}
2296
2297	location.objectid = BTRFS_QUOTA_TREE_OBJECTID;
2298	root = btrfs_read_tree_root(tree_root, &location);
2299	if (!IS_ERR(root)) {
2300		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
 
2301		fs_info->quota_root = root;
2302	}
2303
2304	location.objectid = BTRFS_UUID_TREE_OBJECTID;
2305	root = btrfs_read_tree_root(tree_root, &location);
2306	if (IS_ERR(root)) {
2307		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2308			ret = PTR_ERR(root);
2309			if (ret != -ENOENT)
2310				goto out;
2311		}
2312	} else {
2313		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2314		fs_info->uuid_root = root;
2315	}
2316
2317	if (btrfs_fs_incompat(fs_info, RAID_STRIPE_TREE)) {
2318		location.objectid = BTRFS_RAID_STRIPE_TREE_OBJECTID;
2319		root = btrfs_read_tree_root(tree_root, &location);
2320		if (IS_ERR(root)) {
2321			if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2322				ret = PTR_ERR(root);
2323				goto out;
2324			}
2325		} else {
2326			set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2327			fs_info->stripe_root = root;
2328		}
2329	}
2330
2331	return 0;
2332out:
2333	btrfs_warn(fs_info, "failed to read root (objectid=%llu): %d",
2334		   location.objectid, ret);
2335	return ret;
2336}
2337
2338/*
2339 * Real super block validation
2340 * NOTE: super csum type and incompat features will not be checked here.
2341 *
2342 * @sb:		super block to check
2343 * @mirror_num:	the super block number to check its bytenr:
2344 * 		0	the primary (1st) sb
2345 * 		1, 2	2nd and 3rd backup copy
2346 * 	       -1	skip bytenr check
2347 */
2348int btrfs_validate_super(struct btrfs_fs_info *fs_info,
2349			 struct btrfs_super_block *sb, int mirror_num)
2350{
2351	u64 nodesize = btrfs_super_nodesize(sb);
2352	u64 sectorsize = btrfs_super_sectorsize(sb);
2353	int ret = 0;
2354
2355	if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
2356		btrfs_err(fs_info, "no valid FS found");
2357		ret = -EINVAL;
2358	}
2359	if (btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP) {
2360		btrfs_err(fs_info, "unrecognized or unsupported super flag: %llu",
2361				btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);
2362		ret = -EINVAL;
2363	}
2364	if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
2365		btrfs_err(fs_info, "tree_root level too big: %d >= %d",
2366				btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
2367		ret = -EINVAL;
2368	}
2369	if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
2370		btrfs_err(fs_info, "chunk_root level too big: %d >= %d",
2371				btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
2372		ret = -EINVAL;
2373	}
2374	if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
2375		btrfs_err(fs_info, "log_root level too big: %d >= %d",
2376				btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
2377		ret = -EINVAL;
2378	}
2379
2380	/*
2381	 * Check sectorsize and nodesize first, other check will need it.
2382	 * Check all possible sectorsize(4K, 8K, 16K, 32K, 64K) here.
2383	 */
2384	if (!is_power_of_2(sectorsize) || sectorsize < 4096 ||
2385	    sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2386		btrfs_err(fs_info, "invalid sectorsize %llu", sectorsize);
2387		ret = -EINVAL;
2388	}
2389
2390	/*
2391	 * We only support at most two sectorsizes: 4K and PAGE_SIZE.
2392	 *
2393	 * We can support 16K sectorsize with 64K page size without problem,
2394	 * but such sectorsize/pagesize combination doesn't make much sense.
2395	 * 4K will be our future standard, PAGE_SIZE is supported from the very
2396	 * beginning.
2397	 */
2398	if (sectorsize > PAGE_SIZE || (sectorsize != SZ_4K && sectorsize != PAGE_SIZE)) {
2399		btrfs_err(fs_info,
2400			"sectorsize %llu not yet supported for page size %lu",
2401			sectorsize, PAGE_SIZE);
2402		ret = -EINVAL;
2403	}
2404
2405	if (!is_power_of_2(nodesize) || nodesize < sectorsize ||
2406	    nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2407		btrfs_err(fs_info, "invalid nodesize %llu", nodesize);
2408		ret = -EINVAL;
2409	}
2410	if (nodesize != le32_to_cpu(sb->__unused_leafsize)) {
2411		btrfs_err(fs_info, "invalid leafsize %u, should be %llu",
2412			  le32_to_cpu(sb->__unused_leafsize), nodesize);
2413		ret = -EINVAL;
2414	}
2415
2416	/* Root alignment check */
2417	if (!IS_ALIGNED(btrfs_super_root(sb), sectorsize)) {
2418		btrfs_warn(fs_info, "tree_root block unaligned: %llu",
2419			   btrfs_super_root(sb));
2420		ret = -EINVAL;
2421	}
2422	if (!IS_ALIGNED(btrfs_super_chunk_root(sb), sectorsize)) {
2423		btrfs_warn(fs_info, "chunk_root block unaligned: %llu",
2424			   btrfs_super_chunk_root(sb));
2425		ret = -EINVAL;
2426	}
2427	if (!IS_ALIGNED(btrfs_super_log_root(sb), sectorsize)) {
2428		btrfs_warn(fs_info, "log_root block unaligned: %llu",
2429			   btrfs_super_log_root(sb));
2430		ret = -EINVAL;
2431	}
2432
2433	if (!fs_info->fs_devices->temp_fsid &&
2434	    memcmp(fs_info->fs_devices->fsid, sb->fsid, BTRFS_FSID_SIZE) != 0) {
2435		btrfs_err(fs_info,
2436		"superblock fsid doesn't match fsid of fs_devices: %pU != %pU",
2437			  sb->fsid, fs_info->fs_devices->fsid);
2438		ret = -EINVAL;
2439	}
2440
2441	if (memcmp(fs_info->fs_devices->metadata_uuid, btrfs_sb_fsid_ptr(sb),
2442		   BTRFS_FSID_SIZE) != 0) {
 
2443		btrfs_err(fs_info,
2444"superblock metadata_uuid doesn't match metadata uuid of fs_devices: %pU != %pU",
2445			  btrfs_sb_fsid_ptr(sb), fs_info->fs_devices->metadata_uuid);
2446		ret = -EINVAL;
2447	}
2448
2449	if (memcmp(fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid,
2450		   BTRFS_FSID_SIZE) != 0) {
2451		btrfs_err(fs_info,
2452			"dev_item UUID does not match metadata fsid: %pU != %pU",
2453			fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid);
2454		ret = -EINVAL;
2455	}
2456
2457	/*
2458	 * Artificial requirement for block-group-tree to force newer features
2459	 * (free-space-tree, no-holes) so the test matrix is smaller.
2460	 */
2461	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE) &&
2462	    (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID) ||
2463	     !btrfs_fs_incompat(fs_info, NO_HOLES))) {
2464		btrfs_err(fs_info,
2465		"block-group-tree feature requires fres-space-tree and no-holes");
2466		ret = -EINVAL;
2467	}
2468
 
 
 
 
 
 
 
 
2469	/*
2470	 * Hint to catch really bogus numbers, bitflips or so, more exact checks are
2471	 * done later
2472	 */
2473	if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) {
2474		btrfs_err(fs_info, "bytes_used is too small %llu",
2475			  btrfs_super_bytes_used(sb));
2476		ret = -EINVAL;
2477	}
2478	if (!is_power_of_2(btrfs_super_stripesize(sb))) {
2479		btrfs_err(fs_info, "invalid stripesize %u",
2480			  btrfs_super_stripesize(sb));
2481		ret = -EINVAL;
2482	}
2483	if (btrfs_super_num_devices(sb) > (1UL << 31))
2484		btrfs_warn(fs_info, "suspicious number of devices: %llu",
2485			   btrfs_super_num_devices(sb));
2486	if (btrfs_super_num_devices(sb) == 0) {
2487		btrfs_err(fs_info, "number of devices is 0");
2488		ret = -EINVAL;
2489	}
2490
2491	if (mirror_num >= 0 &&
2492	    btrfs_super_bytenr(sb) != btrfs_sb_offset(mirror_num)) {
2493		btrfs_err(fs_info, "super offset mismatch %llu != %u",
2494			  btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET);
2495		ret = -EINVAL;
2496	}
2497
2498	/*
2499	 * Obvious sys_chunk_array corruptions, it must hold at least one key
2500	 * and one chunk
2501	 */
2502	if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
2503		btrfs_err(fs_info, "system chunk array too big %u > %u",
2504			  btrfs_super_sys_array_size(sb),
2505			  BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
2506		ret = -EINVAL;
2507	}
2508	if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
2509			+ sizeof(struct btrfs_chunk)) {
2510		btrfs_err(fs_info, "system chunk array too small %u < %zu",
2511			  btrfs_super_sys_array_size(sb),
2512			  sizeof(struct btrfs_disk_key)
2513			  + sizeof(struct btrfs_chunk));
2514		ret = -EINVAL;
2515	}
2516
2517	/*
2518	 * The generation is a global counter, we'll trust it more than the others
2519	 * but it's still possible that it's the one that's wrong.
2520	 */
2521	if (btrfs_super_generation(sb) < btrfs_super_chunk_root_generation(sb))
2522		btrfs_warn(fs_info,
2523			"suspicious: generation < chunk_root_generation: %llu < %llu",
2524			btrfs_super_generation(sb),
2525			btrfs_super_chunk_root_generation(sb));
2526	if (btrfs_super_generation(sb) < btrfs_super_cache_generation(sb)
2527	    && btrfs_super_cache_generation(sb) != (u64)-1)
2528		btrfs_warn(fs_info,
2529			"suspicious: generation < cache_generation: %llu < %llu",
2530			btrfs_super_generation(sb),
2531			btrfs_super_cache_generation(sb));
2532
2533	return ret;
2534}
2535
2536/*
2537 * Validation of super block at mount time.
2538 * Some checks already done early at mount time, like csum type and incompat
2539 * flags will be skipped.
2540 */
2541static int btrfs_validate_mount_super(struct btrfs_fs_info *fs_info)
2542{
2543	return btrfs_validate_super(fs_info, fs_info->super_copy, 0);
2544}
2545
2546/*
2547 * Validation of super block at write time.
2548 * Some checks like bytenr check will be skipped as their values will be
2549 * overwritten soon.
2550 * Extra checks like csum type and incompat flags will be done here.
2551 */
2552static int btrfs_validate_write_super(struct btrfs_fs_info *fs_info,
2553				      struct btrfs_super_block *sb)
2554{
2555	int ret;
2556
2557	ret = btrfs_validate_super(fs_info, sb, -1);
2558	if (ret < 0)
2559		goto out;
2560	if (!btrfs_supported_super_csum(btrfs_super_csum_type(sb))) {
2561		ret = -EUCLEAN;
2562		btrfs_err(fs_info, "invalid csum type, has %u want %u",
2563			  btrfs_super_csum_type(sb), BTRFS_CSUM_TYPE_CRC32);
2564		goto out;
2565	}
2566	if (btrfs_super_incompat_flags(sb) & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
2567		ret = -EUCLEAN;
2568		btrfs_err(fs_info,
2569		"invalid incompat flags, has 0x%llx valid mask 0x%llx",
2570			  btrfs_super_incompat_flags(sb),
2571			  (unsigned long long)BTRFS_FEATURE_INCOMPAT_SUPP);
2572		goto out;
2573	}
2574out:
2575	if (ret < 0)
2576		btrfs_err(fs_info,
2577		"super block corruption detected before writing it to disk");
2578	return ret;
2579}
2580
2581static int load_super_root(struct btrfs_root *root, u64 bytenr, u64 gen, int level)
2582{
2583	struct btrfs_tree_parent_check check = {
2584		.level = level,
2585		.transid = gen,
2586		.owner_root = root->root_key.objectid
2587	};
2588	int ret = 0;
2589
2590	root->node = read_tree_block(root->fs_info, bytenr, &check);
2591	if (IS_ERR(root->node)) {
2592		ret = PTR_ERR(root->node);
2593		root->node = NULL;
2594		return ret;
2595	}
2596	if (!extent_buffer_uptodate(root->node)) {
2597		free_extent_buffer(root->node);
2598		root->node = NULL;
2599		return -EIO;
2600	}
2601
2602	btrfs_set_root_node(&root->root_item, root->node);
2603	root->commit_root = btrfs_root_node(root);
2604	btrfs_set_root_refs(&root->root_item, 1);
2605	return ret;
2606}
2607
2608static int load_important_roots(struct btrfs_fs_info *fs_info)
2609{
2610	struct btrfs_super_block *sb = fs_info->super_copy;
2611	u64 gen, bytenr;
2612	int level, ret;
2613
2614	bytenr = btrfs_super_root(sb);
2615	gen = btrfs_super_generation(sb);
2616	level = btrfs_super_root_level(sb);
2617	ret = load_super_root(fs_info->tree_root, bytenr, gen, level);
2618	if (ret) {
2619		btrfs_warn(fs_info, "couldn't read tree root");
2620		return ret;
2621	}
2622	return 0;
2623}
2624
2625static int __cold init_tree_roots(struct btrfs_fs_info *fs_info)
2626{
2627	int backup_index = find_newest_super_backup(fs_info);
2628	struct btrfs_super_block *sb = fs_info->super_copy;
2629	struct btrfs_root *tree_root = fs_info->tree_root;
2630	bool handle_error = false;
2631	int ret = 0;
2632	int i;
2633
2634	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
2635		if (handle_error) {
2636			if (!IS_ERR(tree_root->node))
2637				free_extent_buffer(tree_root->node);
2638			tree_root->node = NULL;
2639
2640			if (!btrfs_test_opt(fs_info, USEBACKUPROOT))
2641				break;
2642
2643			free_root_pointers(fs_info, 0);
2644
2645			/*
2646			 * Don't use the log in recovery mode, it won't be
2647			 * valid
2648			 */
2649			btrfs_set_super_log_root(sb, 0);
2650
2651			btrfs_warn(fs_info, "try to load backup roots slot %d", i);
 
 
2652			ret = read_backup_root(fs_info, i);
2653			backup_index = ret;
2654			if (ret < 0)
2655				return ret;
2656		}
2657
2658		ret = load_important_roots(fs_info);
2659		if (ret) {
2660			handle_error = true;
2661			continue;
2662		}
2663
2664		/*
2665		 * No need to hold btrfs_root::objectid_mutex since the fs
2666		 * hasn't been fully initialised and we are the only user
2667		 */
2668		ret = btrfs_init_root_free_objectid(tree_root);
2669		if (ret < 0) {
2670			handle_error = true;
2671			continue;
2672		}
2673
2674		ASSERT(tree_root->free_objectid <= BTRFS_LAST_FREE_OBJECTID);
2675
2676		ret = btrfs_read_roots(fs_info);
2677		if (ret < 0) {
2678			handle_error = true;
2679			continue;
2680		}
2681
2682		/* All successful */
2683		fs_info->generation = btrfs_header_generation(tree_root->node);
2684		btrfs_set_last_trans_committed(fs_info, fs_info->generation);
2685		fs_info->last_reloc_trans = 0;
2686
2687		/* Always begin writing backup roots after the one being used */
2688		if (backup_index < 0) {
2689			fs_info->backup_root_index = 0;
2690		} else {
2691			fs_info->backup_root_index = backup_index + 1;
2692			fs_info->backup_root_index %= BTRFS_NUM_BACKUP_ROOTS;
2693		}
2694		break;
2695	}
2696
2697	return ret;
2698}
2699
2700void btrfs_init_fs_info(struct btrfs_fs_info *fs_info)
2701{
2702	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
2703	INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC);
2704	INIT_LIST_HEAD(&fs_info->trans_list);
2705	INIT_LIST_HEAD(&fs_info->dead_roots);
2706	INIT_LIST_HEAD(&fs_info->delayed_iputs);
2707	INIT_LIST_HEAD(&fs_info->delalloc_roots);
2708	INIT_LIST_HEAD(&fs_info->caching_block_groups);
2709	spin_lock_init(&fs_info->delalloc_root_lock);
2710	spin_lock_init(&fs_info->trans_lock);
2711	spin_lock_init(&fs_info->fs_roots_radix_lock);
2712	spin_lock_init(&fs_info->delayed_iput_lock);
2713	spin_lock_init(&fs_info->defrag_inodes_lock);
2714	spin_lock_init(&fs_info->super_lock);
2715	spin_lock_init(&fs_info->buffer_lock);
2716	spin_lock_init(&fs_info->unused_bgs_lock);
2717	spin_lock_init(&fs_info->treelog_bg_lock);
2718	spin_lock_init(&fs_info->zone_active_bgs_lock);
2719	spin_lock_init(&fs_info->relocation_bg_lock);
2720	rwlock_init(&fs_info->tree_mod_log_lock);
2721	rwlock_init(&fs_info->global_root_lock);
2722	mutex_init(&fs_info->unused_bg_unpin_mutex);
2723	mutex_init(&fs_info->reclaim_bgs_lock);
2724	mutex_init(&fs_info->reloc_mutex);
2725	mutex_init(&fs_info->delalloc_root_mutex);
2726	mutex_init(&fs_info->zoned_meta_io_lock);
2727	mutex_init(&fs_info->zoned_data_reloc_io_lock);
2728	seqlock_init(&fs_info->profiles_lock);
2729
2730	btrfs_lockdep_init_map(fs_info, btrfs_trans_num_writers);
2731	btrfs_lockdep_init_map(fs_info, btrfs_trans_num_extwriters);
2732	btrfs_lockdep_init_map(fs_info, btrfs_trans_pending_ordered);
2733	btrfs_lockdep_init_map(fs_info, btrfs_ordered_extent);
2734	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_commit_prep,
2735				     BTRFS_LOCKDEP_TRANS_COMMIT_PREP);
2736	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_unblocked,
2737				     BTRFS_LOCKDEP_TRANS_UNBLOCKED);
2738	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_super_committed,
2739				     BTRFS_LOCKDEP_TRANS_SUPER_COMMITTED);
2740	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_completed,
2741				     BTRFS_LOCKDEP_TRANS_COMPLETED);
2742
2743	INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
2744	INIT_LIST_HEAD(&fs_info->space_info);
2745	INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
2746	INIT_LIST_HEAD(&fs_info->unused_bgs);
2747	INIT_LIST_HEAD(&fs_info->reclaim_bgs);
2748	INIT_LIST_HEAD(&fs_info->zone_active_bgs);
2749#ifdef CONFIG_BTRFS_DEBUG
2750	INIT_LIST_HEAD(&fs_info->allocated_roots);
2751	INIT_LIST_HEAD(&fs_info->allocated_ebs);
2752	spin_lock_init(&fs_info->eb_leak_lock);
2753#endif
2754	fs_info->mapping_tree = RB_ROOT_CACHED;
2755	rwlock_init(&fs_info->mapping_tree_lock);
2756	btrfs_init_block_rsv(&fs_info->global_block_rsv,
2757			     BTRFS_BLOCK_RSV_GLOBAL);
2758	btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
2759	btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK);
2760	btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY);
2761	btrfs_init_block_rsv(&fs_info->delayed_block_rsv,
2762			     BTRFS_BLOCK_RSV_DELOPS);
2763	btrfs_init_block_rsv(&fs_info->delayed_refs_rsv,
2764			     BTRFS_BLOCK_RSV_DELREFS);
2765
2766	atomic_set(&fs_info->async_delalloc_pages, 0);
2767	atomic_set(&fs_info->defrag_running, 0);
2768	atomic_set(&fs_info->nr_delayed_iputs, 0);
2769	atomic64_set(&fs_info->tree_mod_seq, 0);
2770	fs_info->global_root_tree = RB_ROOT;
2771	fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE;
2772	fs_info->metadata_ratio = 0;
2773	fs_info->defrag_inodes = RB_ROOT;
2774	atomic64_set(&fs_info->free_chunk_space, 0);
2775	fs_info->tree_mod_log = RB_ROOT;
2776	fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
 
2777	btrfs_init_ref_verify(fs_info);
2778
2779	fs_info->thread_pool_size = min_t(unsigned long,
2780					  num_online_cpus() + 2, 8);
2781
2782	INIT_LIST_HEAD(&fs_info->ordered_roots);
2783	spin_lock_init(&fs_info->ordered_root_lock);
2784
2785	btrfs_init_scrub(fs_info);
 
 
 
2786	btrfs_init_balance(fs_info);
2787	btrfs_init_async_reclaim_work(fs_info);
2788
2789	rwlock_init(&fs_info->block_group_cache_lock);
2790	fs_info->block_group_cache_tree = RB_ROOT_CACHED;
2791
2792	extent_io_tree_init(fs_info, &fs_info->excluded_extents,
2793			    IO_TREE_FS_EXCLUDED_EXTENTS);
2794
2795	mutex_init(&fs_info->ordered_operations_mutex);
2796	mutex_init(&fs_info->tree_log_mutex);
2797	mutex_init(&fs_info->chunk_mutex);
2798	mutex_init(&fs_info->transaction_kthread_mutex);
2799	mutex_init(&fs_info->cleaner_mutex);
2800	mutex_init(&fs_info->ro_block_group_mutex);
2801	init_rwsem(&fs_info->commit_root_sem);
2802	init_rwsem(&fs_info->cleanup_work_sem);
2803	init_rwsem(&fs_info->subvol_sem);
2804	sema_init(&fs_info->uuid_tree_rescan_sem, 1);
2805
2806	btrfs_init_dev_replace_locks(fs_info);
2807	btrfs_init_qgroup(fs_info);
2808	btrfs_discard_init(fs_info);
2809
2810	btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
2811	btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
2812
2813	init_waitqueue_head(&fs_info->transaction_throttle);
2814	init_waitqueue_head(&fs_info->transaction_wait);
2815	init_waitqueue_head(&fs_info->transaction_blocked_wait);
2816	init_waitqueue_head(&fs_info->async_submit_wait);
2817	init_waitqueue_head(&fs_info->delayed_iputs_wait);
2818
2819	/* Usable values until the real ones are cached from the superblock */
2820	fs_info->nodesize = 4096;
2821	fs_info->sectorsize = 4096;
2822	fs_info->sectorsize_bits = ilog2(4096);
2823	fs_info->stripesize = 4096;
2824
2825	/* Default compress algorithm when user does -o compress */
2826	fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
2827
2828	fs_info->max_extent_size = BTRFS_MAX_EXTENT_SIZE;
2829
2830	spin_lock_init(&fs_info->swapfile_pins_lock);
2831	fs_info->swapfile_pins = RB_ROOT;
2832
2833	fs_info->bg_reclaim_threshold = BTRFS_DEFAULT_RECLAIM_THRESH;
2834	INIT_WORK(&fs_info->reclaim_bgs_work, btrfs_reclaim_bgs_work);
2835}
2836
2837static int init_mount_fs_info(struct btrfs_fs_info *fs_info, struct super_block *sb)
2838{
2839	int ret;
2840
2841	fs_info->sb = sb;
2842	sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE;
2843	sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE);
2844
2845	ret = percpu_counter_init(&fs_info->ordered_bytes, 0, GFP_KERNEL);
2846	if (ret)
2847		return ret;
2848
2849	ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0, GFP_KERNEL);
2850	if (ret)
2851		return ret;
2852
2853	fs_info->dirty_metadata_batch = PAGE_SIZE *
2854					(1 + ilog2(nr_cpu_ids));
2855
2856	ret = percpu_counter_init(&fs_info->delalloc_bytes, 0, GFP_KERNEL);
2857	if (ret)
2858		return ret;
2859
2860	ret = percpu_counter_init(&fs_info->dev_replace.bio_counter, 0,
2861			GFP_KERNEL);
2862	if (ret)
2863		return ret;
2864
2865	fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
2866					GFP_KERNEL);
2867	if (!fs_info->delayed_root)
2868		return -ENOMEM;
2869	btrfs_init_delayed_root(fs_info->delayed_root);
2870
2871	if (sb_rdonly(sb))
2872		set_bit(BTRFS_FS_STATE_RO, &fs_info->fs_state);
2873
2874	return btrfs_alloc_stripe_hash_table(fs_info);
2875}
2876
2877static int btrfs_uuid_rescan_kthread(void *data)
2878{
2879	struct btrfs_fs_info *fs_info = data;
2880	int ret;
2881
2882	/*
2883	 * 1st step is to iterate through the existing UUID tree and
2884	 * to delete all entries that contain outdated data.
2885	 * 2nd step is to add all missing entries to the UUID tree.
2886	 */
2887	ret = btrfs_uuid_tree_iterate(fs_info);
2888	if (ret < 0) {
2889		if (ret != -EINTR)
2890			btrfs_warn(fs_info, "iterating uuid_tree failed %d",
2891				   ret);
2892		up(&fs_info->uuid_tree_rescan_sem);
2893		return ret;
2894	}
2895	return btrfs_uuid_scan_kthread(data);
2896}
2897
2898static int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
2899{
2900	struct task_struct *task;
2901
2902	down(&fs_info->uuid_tree_rescan_sem);
2903	task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
2904	if (IS_ERR(task)) {
2905		/* fs_info->update_uuid_tree_gen remains 0 in all error case */
2906		btrfs_warn(fs_info, "failed to start uuid_rescan task");
2907		up(&fs_info->uuid_tree_rescan_sem);
2908		return PTR_ERR(task);
2909	}
2910
2911	return 0;
2912}
2913
2914static int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
 
 
 
 
 
2915{
2916	u64 root_objectid = 0;
2917	struct btrfs_root *gang[8];
2918	int i = 0;
2919	int err = 0;
2920	unsigned int ret = 0;
2921
2922	while (1) {
2923		spin_lock(&fs_info->fs_roots_radix_lock);
2924		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2925					     (void **)gang, root_objectid,
2926					     ARRAY_SIZE(gang));
2927		if (!ret) {
2928			spin_unlock(&fs_info->fs_roots_radix_lock);
2929			break;
2930		}
2931		root_objectid = gang[ret - 1]->root_key.objectid + 1;
2932
2933		for (i = 0; i < ret; i++) {
2934			/* Avoid to grab roots in dead_roots. */
2935			if (btrfs_root_refs(&gang[i]->root_item) == 0) {
2936				gang[i] = NULL;
2937				continue;
2938			}
2939			/* Grab all the search result for later use. */
2940			gang[i] = btrfs_grab_root(gang[i]);
2941		}
2942		spin_unlock(&fs_info->fs_roots_radix_lock);
2943
2944		for (i = 0; i < ret; i++) {
2945			if (!gang[i])
2946				continue;
2947			root_objectid = gang[i]->root_key.objectid;
2948			err = btrfs_orphan_cleanup(gang[i]);
2949			if (err)
2950				goto out;
2951			btrfs_put_root(gang[i]);
2952		}
2953		root_objectid++;
2954	}
2955out:
2956	/* Release the uncleaned roots due to error. */
2957	for (; i < ret; i++) {
2958		if (gang[i])
2959			btrfs_put_root(gang[i]);
2960	}
2961	return err;
2962}
2963
2964/*
2965 * Mounting logic specific to read-write file systems. Shared by open_ctree
2966 * and btrfs_remount when remounting from read-only to read-write.
2967 */
2968int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info)
2969{
2970	int ret;
2971	const bool cache_opt = btrfs_test_opt(fs_info, SPACE_CACHE);
2972	bool rebuild_free_space_tree = false;
2973
2974	if (btrfs_test_opt(fs_info, CLEAR_CACHE) &&
2975	    btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
2976		if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
2977			btrfs_warn(fs_info,
2978				   "'clear_cache' option is ignored with extent tree v2");
2979		else
2980			rebuild_free_space_tree = true;
2981	} else if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
2982		   !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID)) {
2983		btrfs_warn(fs_info, "free space tree is invalid");
2984		rebuild_free_space_tree = true;
2985	}
2986
2987	if (rebuild_free_space_tree) {
2988		btrfs_info(fs_info, "rebuilding free space tree");
2989		ret = btrfs_rebuild_free_space_tree(fs_info);
2990		if (ret) {
2991			btrfs_warn(fs_info,
2992				   "failed to rebuild free space tree: %d", ret);
2993			goto out;
2994		}
2995	}
2996
2997	if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
2998	    !btrfs_test_opt(fs_info, FREE_SPACE_TREE)) {
2999		btrfs_info(fs_info, "disabling free space tree");
3000		ret = btrfs_delete_free_space_tree(fs_info);
3001		if (ret) {
3002			btrfs_warn(fs_info,
3003				   "failed to disable free space tree: %d", ret);
3004			goto out;
3005		}
3006	}
3007
3008	/*
3009	 * btrfs_find_orphan_roots() is responsible for finding all the dead
3010	 * roots (with 0 refs), flag them with BTRFS_ROOT_DEAD_TREE and load
3011	 * them into the fs_info->fs_roots_radix tree. This must be done before
3012	 * calling btrfs_orphan_cleanup() on the tree root. If we don't do it
3013	 * first, then btrfs_orphan_cleanup() will delete a dead root's orphan
3014	 * item before the root's tree is deleted - this means that if we unmount
3015	 * or crash before the deletion completes, on the next mount we will not
3016	 * delete what remains of the tree because the orphan item does not
3017	 * exists anymore, which is what tells us we have a pending deletion.
3018	 */
3019	ret = btrfs_find_orphan_roots(fs_info);
3020	if (ret)
3021		goto out;
3022
3023	ret = btrfs_cleanup_fs_roots(fs_info);
3024	if (ret)
3025		goto out;
3026
3027	down_read(&fs_info->cleanup_work_sem);
3028	if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) ||
3029	    (ret = btrfs_orphan_cleanup(fs_info->tree_root))) {
3030		up_read(&fs_info->cleanup_work_sem);
3031		goto out;
3032	}
3033	up_read(&fs_info->cleanup_work_sem);
3034
3035	mutex_lock(&fs_info->cleaner_mutex);
3036	ret = btrfs_recover_relocation(fs_info);
3037	mutex_unlock(&fs_info->cleaner_mutex);
3038	if (ret < 0) {
3039		btrfs_warn(fs_info, "failed to recover relocation: %d", ret);
3040		goto out;
3041	}
3042
3043	if (btrfs_test_opt(fs_info, FREE_SPACE_TREE) &&
3044	    !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3045		btrfs_info(fs_info, "creating free space tree");
3046		ret = btrfs_create_free_space_tree(fs_info);
3047		if (ret) {
3048			btrfs_warn(fs_info,
3049				"failed to create free space tree: %d", ret);
3050			goto out;
3051		}
3052	}
3053
3054	if (cache_opt != btrfs_free_space_cache_v1_active(fs_info)) {
3055		ret = btrfs_set_free_space_cache_v1_active(fs_info, cache_opt);
3056		if (ret)
3057			goto out;
3058	}
3059
3060	ret = btrfs_resume_balance_async(fs_info);
3061	if (ret)
3062		goto out;
3063
3064	ret = btrfs_resume_dev_replace_async(fs_info);
3065	if (ret) {
3066		btrfs_warn(fs_info, "failed to resume dev_replace");
3067		goto out;
3068	}
3069
3070	btrfs_qgroup_rescan_resume(fs_info);
3071
3072	if (!fs_info->uuid_root) {
3073		btrfs_info(fs_info, "creating UUID tree");
3074		ret = btrfs_create_uuid_tree(fs_info);
3075		if (ret) {
3076			btrfs_warn(fs_info,
3077				   "failed to create the UUID tree %d", ret);
3078			goto out;
3079		}
3080	}
3081
3082out:
3083	return ret;
3084}
3085
3086/*
3087 * Do various sanity and dependency checks of different features.
3088 *
3089 * @is_rw_mount:	If the mount is read-write.
3090 *
3091 * This is the place for less strict checks (like for subpage or artificial
3092 * feature dependencies).
3093 *
3094 * For strict checks or possible corruption detection, see
3095 * btrfs_validate_super().
3096 *
3097 * This should be called after btrfs_parse_options(), as some mount options
3098 * (space cache related) can modify on-disk format like free space tree and
3099 * screw up certain feature dependencies.
3100 */
3101int btrfs_check_features(struct btrfs_fs_info *fs_info, bool is_rw_mount)
3102{
3103	struct btrfs_super_block *disk_super = fs_info->super_copy;
3104	u64 incompat = btrfs_super_incompat_flags(disk_super);
3105	const u64 compat_ro = btrfs_super_compat_ro_flags(disk_super);
3106	const u64 compat_ro_unsupp = (compat_ro & ~BTRFS_FEATURE_COMPAT_RO_SUPP);
3107
3108	if (incompat & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
3109		btrfs_err(fs_info,
3110		"cannot mount because of unknown incompat features (0x%llx)",
3111		    incompat);
3112		return -EINVAL;
3113	}
3114
3115	/* Runtime limitation for mixed block groups. */
3116	if ((incompat & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
3117	    (fs_info->sectorsize != fs_info->nodesize)) {
3118		btrfs_err(fs_info,
3119"unequal nodesize/sectorsize (%u != %u) are not allowed for mixed block groups",
3120			fs_info->nodesize, fs_info->sectorsize);
3121		return -EINVAL;
3122	}
3123
3124	/* Mixed backref is an always-enabled feature. */
3125	incompat |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
3126
3127	/* Set compression related flags just in case. */
3128	if (fs_info->compress_type == BTRFS_COMPRESS_LZO)
3129		incompat |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
3130	else if (fs_info->compress_type == BTRFS_COMPRESS_ZSTD)
3131		incompat |= BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD;
3132
3133	/*
3134	 * An ancient flag, which should really be marked deprecated.
3135	 * Such runtime limitation doesn't really need a incompat flag.
3136	 */
3137	if (btrfs_super_nodesize(disk_super) > PAGE_SIZE)
3138		incompat |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
3139
3140	if (compat_ro_unsupp && is_rw_mount) {
3141		btrfs_err(fs_info,
3142	"cannot mount read-write because of unknown compat_ro features (0x%llx)",
3143		       compat_ro);
3144		return -EINVAL;
3145	}
3146
3147	/*
3148	 * We have unsupported RO compat features, although RO mounted, we
3149	 * should not cause any metadata writes, including log replay.
3150	 * Or we could screw up whatever the new feature requires.
3151	 */
3152	if (compat_ro_unsupp && btrfs_super_log_root(disk_super) &&
3153	    !btrfs_test_opt(fs_info, NOLOGREPLAY)) {
3154		btrfs_err(fs_info,
3155"cannot replay dirty log with unsupported compat_ro features (0x%llx), try rescue=nologreplay",
3156			  compat_ro);
3157		return -EINVAL;
3158	}
3159
3160	/*
3161	 * Artificial limitations for block group tree, to force
3162	 * block-group-tree to rely on no-holes and free-space-tree.
3163	 */
3164	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE) &&
3165	    (!btrfs_fs_incompat(fs_info, NO_HOLES) ||
3166	     !btrfs_test_opt(fs_info, FREE_SPACE_TREE))) {
3167		btrfs_err(fs_info,
3168"block-group-tree feature requires no-holes and free-space-tree features");
3169		return -EINVAL;
3170	}
3171
3172	/*
3173	 * Subpage runtime limitation on v1 cache.
3174	 *
3175	 * V1 space cache still has some hard codeed PAGE_SIZE usage, while
3176	 * we're already defaulting to v2 cache, no need to bother v1 as it's
3177	 * going to be deprecated anyway.
3178	 */
3179	if (fs_info->sectorsize < PAGE_SIZE && btrfs_test_opt(fs_info, SPACE_CACHE)) {
3180		btrfs_warn(fs_info,
3181	"v1 space cache is not supported for page size %lu with sectorsize %u",
3182			   PAGE_SIZE, fs_info->sectorsize);
3183		return -EINVAL;
3184	}
3185
3186	/* This can be called by remount, we need to protect the super block. */
3187	spin_lock(&fs_info->super_lock);
3188	btrfs_set_super_incompat_flags(disk_super, incompat);
3189	spin_unlock(&fs_info->super_lock);
3190
3191	return 0;
3192}
3193
3194int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_devices,
3195		      char *options)
3196{
3197	u32 sectorsize;
3198	u32 nodesize;
3199	u32 stripesize;
3200	u64 generation;
 
3201	u16 csum_type;
3202	struct btrfs_super_block *disk_super;
3203	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
3204	struct btrfs_root *tree_root;
3205	struct btrfs_root *chunk_root;
3206	int ret;
 
3207	int level;
3208
3209	ret = init_mount_fs_info(fs_info, sb);
3210	if (ret)
 
3211		goto fail;
 
3212
3213	/* These need to be init'ed before we start creating inodes and such. */
3214	tree_root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID,
3215				     GFP_KERNEL);
3216	fs_info->tree_root = tree_root;
3217	chunk_root = btrfs_alloc_root(fs_info, BTRFS_CHUNK_TREE_OBJECTID,
3218				      GFP_KERNEL);
3219	fs_info->chunk_root = chunk_root;
3220	if (!tree_root || !chunk_root) {
3221		ret = -ENOMEM;
3222		goto fail;
3223	}
3224
3225	ret = btrfs_init_btree_inode(sb);
3226	if (ret)
 
3227		goto fail;
 
 
 
3228
3229	invalidate_bdev(fs_devices->latest_dev->bdev);
3230
3231	/*
3232	 * Read super block and check the signature bytes only
3233	 */
3234	disk_super = btrfs_read_dev_super(fs_devices->latest_dev->bdev);
3235	if (IS_ERR(disk_super)) {
3236		ret = PTR_ERR(disk_super);
3237		goto fail_alloc;
3238	}
3239
3240	btrfs_info(fs_info, "first mount of filesystem %pU", disk_super->fsid);
3241	/*
3242	 * Verify the type first, if that or the checksum value are
3243	 * corrupted, we'll find out
3244	 */
3245	csum_type = btrfs_super_csum_type(disk_super);
3246	if (!btrfs_supported_super_csum(csum_type)) {
3247		btrfs_err(fs_info, "unsupported checksum algorithm: %u",
3248			  csum_type);
3249		ret = -EINVAL;
3250		btrfs_release_disk_super(disk_super);
3251		goto fail_alloc;
3252	}
3253
3254	fs_info->csum_size = btrfs_super_csum_size(disk_super);
3255
3256	ret = btrfs_init_csum_hash(fs_info, csum_type);
3257	if (ret) {
 
3258		btrfs_release_disk_super(disk_super);
3259		goto fail_alloc;
3260	}
3261
3262	/*
3263	 * We want to check superblock checksum, the type is stored inside.
3264	 * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k).
3265	 */
3266	if (btrfs_check_super_csum(fs_info, disk_super)) {
3267		btrfs_err(fs_info, "superblock checksum mismatch");
3268		ret = -EINVAL;
3269		btrfs_release_disk_super(disk_super);
3270		goto fail_alloc;
3271	}
3272
3273	/*
3274	 * super_copy is zeroed at allocation time and we never touch the
3275	 * following bytes up to INFO_SIZE, the checksum is calculated from
3276	 * the whole block of INFO_SIZE
3277	 */
3278	memcpy(fs_info->super_copy, disk_super, sizeof(*fs_info->super_copy));
3279	btrfs_release_disk_super(disk_super);
3280
3281	disk_super = fs_info->super_copy;
3282
 
 
 
 
 
 
 
 
 
3283	memcpy(fs_info->super_for_commit, fs_info->super_copy,
3284	       sizeof(*fs_info->super_for_commit));
3285
3286	ret = btrfs_validate_mount_super(fs_info);
3287	if (ret) {
3288		btrfs_err(fs_info, "superblock contains fatal errors");
3289		ret = -EINVAL;
3290		goto fail_alloc;
3291	}
3292
3293	if (!btrfs_super_root(disk_super)) {
3294		btrfs_err(fs_info, "invalid superblock tree root bytenr");
3295		ret = -EINVAL;
3296		goto fail_alloc;
3297	}
3298
3299	/* check FS state, whether FS is broken. */
3300	if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
3301		WRITE_ONCE(fs_info->fs_error, -EUCLEAN);
 
 
 
 
 
 
 
3302
3303	/* Set up fs_info before parsing mount options */
3304	nodesize = btrfs_super_nodesize(disk_super);
3305	sectorsize = btrfs_super_sectorsize(disk_super);
3306	stripesize = sectorsize;
3307	fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids));
3308	fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
3309
3310	fs_info->nodesize = nodesize;
3311	fs_info->sectorsize = sectorsize;
3312	fs_info->sectorsize_bits = ilog2(sectorsize);
3313	fs_info->csums_per_leaf = BTRFS_MAX_ITEM_SIZE(fs_info) / fs_info->csum_size;
3314	fs_info->stripesize = stripesize;
3315
3316	/*
3317	 * Handle the space caching options appropriately now that we have the
3318	 * super block loaded and validated.
3319	 */
3320	btrfs_set_free_space_cache_settings(fs_info);
3321
3322	if (!btrfs_check_options(fs_info, &fs_info->mount_opt, sb->s_flags)) {
3323		ret = -EINVAL;
3324		goto fail_alloc;
3325	}
3326
3327	ret = btrfs_check_features(fs_info, !sb_rdonly(sb));
3328	if (ret < 0)
 
3329		goto fail_alloc;
3330
3331	/*
3332	 * At this point our mount options are validated, if we set ->max_inline
3333	 * to something non-standard make sure we truncate it to sectorsize.
3334	 */
3335	fs_info->max_inline = min_t(u64, fs_info->max_inline, fs_info->sectorsize);
3336
3337	if (sectorsize < PAGE_SIZE) {
3338		struct btrfs_subpage_info *subpage_info;
3339
 
 
 
 
 
 
 
 
 
 
 
3340		btrfs_warn(fs_info,
3341		"read-write for sector size %u with page size %lu is experimental",
3342			   sectorsize, PAGE_SIZE);
3343		subpage_info = kzalloc(sizeof(*subpage_info), GFP_KERNEL);
3344		if (!subpage_info) {
3345			ret = -ENOMEM;
3346			goto fail_alloc;
3347		}
3348		btrfs_init_subpage_info(subpage_info, sectorsize);
3349		fs_info->subpage_info = subpage_info;
3350	}
3351
3352	ret = btrfs_init_workqueues(fs_info);
3353	if (ret)
 
3354		goto fail_sb_buffer;
 
3355
3356	sb->s_bdi->ra_pages *= btrfs_super_num_devices(disk_super);
3357	sb->s_bdi->ra_pages = max(sb->s_bdi->ra_pages, SZ_4M / PAGE_SIZE);
3358
3359	sb->s_blocksize = sectorsize;
3360	sb->s_blocksize_bits = blksize_bits(sectorsize);
3361	memcpy(&sb->s_uuid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE);
3362
3363	mutex_lock(&fs_info->chunk_mutex);
3364	ret = btrfs_read_sys_array(fs_info);
3365	mutex_unlock(&fs_info->chunk_mutex);
3366	if (ret) {
3367		btrfs_err(fs_info, "failed to read the system array: %d", ret);
3368		goto fail_sb_buffer;
3369	}
3370
3371	generation = btrfs_super_chunk_root_generation(disk_super);
3372	level = btrfs_super_chunk_root_level(disk_super);
3373	ret = load_super_root(chunk_root, btrfs_super_chunk_root(disk_super),
3374			      generation, level);
3375	if (ret) {
3376		btrfs_err(fs_info, "failed to read chunk root");
3377		goto fail_tree_roots;
3378	}
3379
3380	read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
3381			   offsetof(struct btrfs_header, chunk_tree_uuid),
3382			   BTRFS_UUID_SIZE);
3383
3384	ret = btrfs_read_chunk_tree(fs_info);
3385	if (ret) {
3386		btrfs_err(fs_info, "failed to read chunk tree: %d", ret);
3387		goto fail_tree_roots;
3388	}
3389
3390	/*
3391	 * At this point we know all the devices that make this filesystem,
3392	 * including the seed devices but we don't know yet if the replace
3393	 * target is required. So free devices that are not part of this
3394	 * filesystem but skip the replace target device which is checked
3395	 * below in btrfs_init_dev_replace().
3396	 */
3397	btrfs_free_extra_devids(fs_devices);
3398	if (!fs_devices->latest_dev->bdev) {
3399		btrfs_err(fs_info, "failed to read devices");
3400		ret = -EIO;
3401		goto fail_tree_roots;
3402	}
3403
3404	ret = init_tree_roots(fs_info);
3405	if (ret)
3406		goto fail_tree_roots;
3407
3408	/*
3409	 * Get zone type information of zoned block devices. This will also
3410	 * handle emulation of a zoned filesystem if a regular device has the
3411	 * zoned incompat feature flag set.
3412	 */
3413	ret = btrfs_get_dev_zone_info_all_devices(fs_info);
3414	if (ret) {
3415		btrfs_err(fs_info,
3416			  "zoned: failed to read device zone info: %d", ret);
 
3417		goto fail_block_groups;
3418	}
3419
3420	/*
3421	 * If we have a uuid root and we're not being told to rescan we need to
3422	 * check the generation here so we can set the
3423	 * BTRFS_FS_UPDATE_UUID_TREE_GEN bit.  Otherwise we could commit the
3424	 * transaction during a balance or the log replay without updating the
3425	 * uuid generation, and then if we crash we would rescan the uuid tree,
3426	 * even though it was perfectly fine.
3427	 */
3428	if (fs_info->uuid_root && !btrfs_test_opt(fs_info, RESCAN_UUID_TREE) &&
3429	    fs_info->generation == btrfs_super_uuid_tree_generation(disk_super))
3430		set_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags);
3431
3432	ret = btrfs_verify_dev_extents(fs_info);
3433	if (ret) {
3434		btrfs_err(fs_info,
3435			  "failed to verify dev extents against chunks: %d",
3436			  ret);
3437		goto fail_block_groups;
3438	}
3439	ret = btrfs_recover_balance(fs_info);
3440	if (ret) {
3441		btrfs_err(fs_info, "failed to recover balance: %d", ret);
3442		goto fail_block_groups;
3443	}
3444
3445	ret = btrfs_init_dev_stats(fs_info);
3446	if (ret) {
3447		btrfs_err(fs_info, "failed to init dev_stats: %d", ret);
3448		goto fail_block_groups;
3449	}
3450
3451	ret = btrfs_init_dev_replace(fs_info);
3452	if (ret) {
3453		btrfs_err(fs_info, "failed to init dev_replace: %d", ret);
3454		goto fail_block_groups;
3455	}
3456
3457	ret = btrfs_check_zoned_mode(fs_info);
3458	if (ret) {
3459		btrfs_err(fs_info, "failed to initialize zoned mode: %d",
3460			  ret);
3461		goto fail_block_groups;
3462	}
3463
3464	ret = btrfs_sysfs_add_fsid(fs_devices);
3465	if (ret) {
3466		btrfs_err(fs_info, "failed to init sysfs fsid interface: %d",
3467				ret);
3468		goto fail_block_groups;
3469	}
3470
3471	ret = btrfs_sysfs_add_mounted(fs_info);
3472	if (ret) {
3473		btrfs_err(fs_info, "failed to init sysfs interface: %d", ret);
3474		goto fail_fsdev_sysfs;
3475	}
3476
3477	ret = btrfs_init_space_info(fs_info);
3478	if (ret) {
3479		btrfs_err(fs_info, "failed to initialize space info: %d", ret);
3480		goto fail_sysfs;
3481	}
3482
3483	ret = btrfs_read_block_groups(fs_info);
3484	if (ret) {
3485		btrfs_err(fs_info, "failed to read block groups: %d", ret);
3486		goto fail_sysfs;
3487	}
3488
3489	btrfs_free_zone_cache(fs_info);
3490
3491	btrfs_check_active_zone_reservation(fs_info);
3492
3493	if (!sb_rdonly(sb) && fs_info->fs_devices->missing_devices &&
3494	    !btrfs_check_rw_degradable(fs_info, NULL)) {
3495		btrfs_warn(fs_info,
3496		"writable mount is not allowed due to too many missing devices");
3497		ret = -EINVAL;
3498		goto fail_sysfs;
3499	}
3500
3501	fs_info->cleaner_kthread = kthread_run(cleaner_kthread, fs_info,
3502					       "btrfs-cleaner");
3503	if (IS_ERR(fs_info->cleaner_kthread)) {
3504		ret = PTR_ERR(fs_info->cleaner_kthread);
3505		goto fail_sysfs;
3506	}
3507
3508	fs_info->transaction_kthread = kthread_run(transaction_kthread,
3509						   tree_root,
3510						   "btrfs-transaction");
3511	if (IS_ERR(fs_info->transaction_kthread)) {
3512		ret = PTR_ERR(fs_info->transaction_kthread);
3513		goto fail_cleaner;
 
 
 
 
3514	}
3515
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3516	ret = btrfs_read_qgroup_config(fs_info);
3517	if (ret)
3518		goto fail_trans_kthread;
3519
3520	if (btrfs_build_ref_tree(fs_info))
3521		btrfs_err(fs_info, "couldn't build ref tree");
3522
3523	/* do not make disk changes in broken FS or nologreplay is given */
3524	if (btrfs_super_log_root(disk_super) != 0 &&
3525	    !btrfs_test_opt(fs_info, NOLOGREPLAY)) {
3526		btrfs_info(fs_info, "start tree-log replay");
3527		ret = btrfs_replay_log(fs_info, fs_devices);
3528		if (ret)
 
3529			goto fail_qgroup;
 
3530	}
3531
3532	fs_info->fs_root = btrfs_get_fs_root(fs_info, BTRFS_FS_TREE_OBJECTID, true);
3533	if (IS_ERR(fs_info->fs_root)) {
3534		ret = PTR_ERR(fs_info->fs_root);
3535		btrfs_warn(fs_info, "failed to read fs tree: %d", ret);
3536		fs_info->fs_root = NULL;
3537		goto fail_qgroup;
3538	}
3539
3540	if (sb_rdonly(sb))
3541		return 0;
3542
3543	ret = btrfs_start_pre_rw_mount(fs_info);
3544	if (ret) {
3545		close_ctree(fs_info);
3546		return ret;
3547	}
3548	btrfs_discard_resume(fs_info);
3549
3550	if (fs_info->uuid_root &&
3551	    (btrfs_test_opt(fs_info, RESCAN_UUID_TREE) ||
3552	     fs_info->generation != btrfs_super_uuid_tree_generation(disk_super))) {
3553		btrfs_info(fs_info, "checking UUID tree");
3554		ret = btrfs_check_uuid_tree(fs_info);
3555		if (ret) {
3556			btrfs_warn(fs_info,
3557				"failed to check the UUID tree: %d", ret);
3558			close_ctree(fs_info);
3559			return ret;
3560		}
3561	}
3562
3563	set_bit(BTRFS_FS_OPEN, &fs_info->flags);
3564
3565	/* Kick the cleaner thread so it'll start deleting snapshots. */
3566	if (test_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags))
3567		wake_up_process(fs_info->cleaner_kthread);
3568
 
 
3569	return 0;
3570
3571fail_qgroup:
3572	btrfs_free_qgroup_config(fs_info);
3573fail_trans_kthread:
3574	kthread_stop(fs_info->transaction_kthread);
3575	btrfs_cleanup_transaction(fs_info);
3576	btrfs_free_fs_roots(fs_info);
3577fail_cleaner:
3578	kthread_stop(fs_info->cleaner_kthread);
3579
3580	/*
3581	 * make sure we're done with the btree inode before we stop our
3582	 * kthreads
3583	 */
3584	filemap_write_and_wait(fs_info->btree_inode->i_mapping);
3585
3586fail_sysfs:
3587	btrfs_sysfs_remove_mounted(fs_info);
3588
3589fail_fsdev_sysfs:
3590	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
3591
3592fail_block_groups:
3593	btrfs_put_block_group_cache(fs_info);
3594
3595fail_tree_roots:
3596	if (fs_info->data_reloc_root)
3597		btrfs_drop_and_free_fs_root(fs_info, fs_info->data_reloc_root);
3598	free_root_pointers(fs_info, true);
3599	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
3600
3601fail_sb_buffer:
3602	btrfs_stop_all_workers(fs_info);
3603	btrfs_free_block_groups(fs_info);
3604fail_alloc:
3605	btrfs_mapping_tree_free(fs_info);
3606
3607	iput(fs_info->btree_inode);
3608fail:
3609	btrfs_close_devices(fs_info->fs_devices);
3610	ASSERT(ret < 0);
3611	return ret;
3612}
3613ALLOW_ERROR_INJECTION(open_ctree, ERRNO);
3614
3615static void btrfs_end_super_write(struct bio *bio)
3616{
3617	struct btrfs_device *device = bio->bi_private;
3618	struct bio_vec *bvec;
3619	struct bvec_iter_all iter_all;
3620	struct page *page;
3621
3622	bio_for_each_segment_all(bvec, bio, iter_all) {
3623		page = bvec->bv_page;
3624
3625		if (bio->bi_status) {
3626			btrfs_warn_rl_in_rcu(device->fs_info,
3627				"lost page write due to IO error on %s (%d)",
3628				btrfs_dev_name(device),
3629				blk_status_to_errno(bio->bi_status));
3630			ClearPageUptodate(page);
3631			SetPageError(page);
3632			btrfs_dev_stat_inc_and_print(device,
3633						     BTRFS_DEV_STAT_WRITE_ERRS);
3634		} else {
3635			SetPageUptodate(page);
3636		}
3637
3638		put_page(page);
3639		unlock_page(page);
3640	}
3641
3642	bio_put(bio);
3643}
3644
3645struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
3646						   int copy_num, bool drop_cache)
3647{
3648	struct btrfs_super_block *super;
3649	struct page *page;
3650	u64 bytenr, bytenr_orig;
3651	struct address_space *mapping = bdev->bd_inode->i_mapping;
3652	int ret;
3653
3654	bytenr_orig = btrfs_sb_offset(copy_num);
3655	ret = btrfs_sb_log_location_bdev(bdev, copy_num, READ, &bytenr);
3656	if (ret == -ENOENT)
3657		return ERR_PTR(-EINVAL);
3658	else if (ret)
3659		return ERR_PTR(ret);
3660
3661	if (bytenr + BTRFS_SUPER_INFO_SIZE >= bdev_nr_bytes(bdev))
3662		return ERR_PTR(-EINVAL);
3663
3664	if (drop_cache) {
3665		/* This should only be called with the primary sb. */
3666		ASSERT(copy_num == 0);
3667
3668		/*
3669		 * Drop the page of the primary superblock, so later read will
3670		 * always read from the device.
3671		 */
3672		invalidate_inode_pages2_range(mapping,
3673				bytenr >> PAGE_SHIFT,
3674				(bytenr + BTRFS_SUPER_INFO_SIZE) >> PAGE_SHIFT);
3675	}
3676
3677	page = read_cache_page_gfp(mapping, bytenr >> PAGE_SHIFT, GFP_NOFS);
3678	if (IS_ERR(page))
3679		return ERR_CAST(page);
3680
3681	super = page_address(page);
3682	if (btrfs_super_magic(super) != BTRFS_MAGIC) {
3683		btrfs_release_disk_super(super);
3684		return ERR_PTR(-ENODATA);
3685	}
3686
3687	if (btrfs_super_bytenr(super) != bytenr_orig) {
3688		btrfs_release_disk_super(super);
3689		return ERR_PTR(-EINVAL);
3690	}
3691
3692	return super;
3693}
3694
3695
3696struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev)
3697{
3698	struct btrfs_super_block *super, *latest = NULL;
3699	int i;
3700	u64 transid = 0;
3701
3702	/* we would like to check all the supers, but that would make
3703	 * a btrfs mount succeed after a mkfs from a different FS.
3704	 * So, we need to add a special mount option to scan for
3705	 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
3706	 */
3707	for (i = 0; i < 1; i++) {
3708		super = btrfs_read_dev_one_super(bdev, i, false);
3709		if (IS_ERR(super))
3710			continue;
3711
3712		if (!latest || btrfs_super_generation(super) > transid) {
3713			if (latest)
3714				btrfs_release_disk_super(super);
3715
3716			latest = super;
3717			transid = btrfs_super_generation(super);
3718		}
3719	}
3720
3721	return super;
3722}
3723
3724/*
3725 * Write superblock @sb to the @device. Do not wait for completion, all the
3726 * pages we use for writing are locked.
3727 *
3728 * Write @max_mirrors copies of the superblock, where 0 means default that fit
3729 * the expected device size at commit time. Note that max_mirrors must be
3730 * same for write and wait phases.
3731 *
3732 * Return number of errors when page is not found or submission fails.
3733 */
3734static int write_dev_supers(struct btrfs_device *device,
3735			    struct btrfs_super_block *sb, int max_mirrors)
3736{
3737	struct btrfs_fs_info *fs_info = device->fs_info;
3738	struct address_space *mapping = device->bdev->bd_inode->i_mapping;
3739	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
3740	int i;
3741	int errors = 0;
3742	int ret;
3743	u64 bytenr, bytenr_orig;
3744
3745	if (max_mirrors == 0)
3746		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
3747
3748	shash->tfm = fs_info->csum_shash;
3749
3750	for (i = 0; i < max_mirrors; i++) {
3751		struct page *page;
3752		struct bio *bio;
3753		struct btrfs_super_block *disk_super;
3754
3755		bytenr_orig = btrfs_sb_offset(i);
3756		ret = btrfs_sb_log_location(device, i, WRITE, &bytenr);
3757		if (ret == -ENOENT) {
3758			continue;
3759		} else if (ret < 0) {
3760			btrfs_err(device->fs_info,
3761				"couldn't get super block location for mirror %d",
3762				i);
3763			errors++;
3764			continue;
3765		}
3766		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
3767		    device->commit_total_bytes)
3768			break;
3769
3770		btrfs_set_super_bytenr(sb, bytenr_orig);
3771
3772		crypto_shash_digest(shash, (const char *)sb + BTRFS_CSUM_SIZE,
3773				    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE,
3774				    sb->csum);
3775
3776		page = find_or_create_page(mapping, bytenr >> PAGE_SHIFT,
3777					   GFP_NOFS);
3778		if (!page) {
3779			btrfs_err(device->fs_info,
3780			    "couldn't get super block page for bytenr %llu",
3781			    bytenr);
3782			errors++;
3783			continue;
3784		}
3785
3786		/* Bump the refcount for wait_dev_supers() */
3787		get_page(page);
3788
3789		disk_super = page_address(page);
3790		memcpy(disk_super, sb, BTRFS_SUPER_INFO_SIZE);
3791
3792		/*
3793		 * Directly use bios here instead of relying on the page cache
3794		 * to do I/O, so we don't lose the ability to do integrity
3795		 * checking.
3796		 */
3797		bio = bio_alloc(device->bdev, 1,
3798				REQ_OP_WRITE | REQ_SYNC | REQ_META | REQ_PRIO,
3799				GFP_NOFS);
3800		bio->bi_iter.bi_sector = bytenr >> SECTOR_SHIFT;
3801		bio->bi_private = device;
3802		bio->bi_end_io = btrfs_end_super_write;
3803		__bio_add_page(bio, page, BTRFS_SUPER_INFO_SIZE,
3804			       offset_in_page(bytenr));
3805
3806		/*
3807		 * We FUA only the first super block.  The others we allow to
3808		 * go down lazy and there's a short window where the on-disk
3809		 * copies might still contain the older version.
3810		 */
3811		if (i == 0 && !btrfs_test_opt(device->fs_info, NOBARRIER))
3812			bio->bi_opf |= REQ_FUA;
 
 
3813		submit_bio(bio);
3814
3815		if (btrfs_advance_sb_log(device, i))
3816			errors++;
3817	}
3818	return errors < i ? 0 : -1;
3819}
3820
3821/*
3822 * Wait for write completion of superblocks done by write_dev_supers,
3823 * @max_mirrors same for write and wait phases.
3824 *
3825 * Return number of errors when page is not found or not marked up to
3826 * date.
3827 */
3828static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
3829{
3830	int i;
3831	int errors = 0;
3832	bool primary_failed = false;
3833	int ret;
3834	u64 bytenr;
3835
3836	if (max_mirrors == 0)
3837		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
3838
3839	for (i = 0; i < max_mirrors; i++) {
3840		struct page *page;
3841
3842		ret = btrfs_sb_log_location(device, i, READ, &bytenr);
3843		if (ret == -ENOENT) {
3844			break;
3845		} else if (ret < 0) {
3846			errors++;
3847			if (i == 0)
3848				primary_failed = true;
3849			continue;
3850		}
3851		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
3852		    device->commit_total_bytes)
3853			break;
3854
3855		page = find_get_page(device->bdev->bd_inode->i_mapping,
3856				     bytenr >> PAGE_SHIFT);
3857		if (!page) {
3858			errors++;
3859			if (i == 0)
3860				primary_failed = true;
3861			continue;
3862		}
3863		/* Page is submitted locked and unlocked once the IO completes */
3864		wait_on_page_locked(page);
3865		if (PageError(page)) {
3866			errors++;
3867			if (i == 0)
3868				primary_failed = true;
3869		}
3870
3871		/* Drop our reference */
3872		put_page(page);
3873
3874		/* Drop the reference from the writing run */
3875		put_page(page);
3876	}
3877
3878	/* log error, force error return */
3879	if (primary_failed) {
3880		btrfs_err(device->fs_info, "error writing primary super block to device %llu",
3881			  device->devid);
3882		return -1;
3883	}
3884
3885	return errors < i ? 0 : -1;
3886}
3887
3888/*
3889 * endio for the write_dev_flush, this will wake anyone waiting
3890 * for the barrier when it is done
3891 */
3892static void btrfs_end_empty_barrier(struct bio *bio)
3893{
3894	bio_uninit(bio);
3895	complete(bio->bi_private);
3896}
3897
3898/*
3899 * Submit a flush request to the device if it supports it. Error handling is
3900 * done in the waiting counterpart.
3901 */
3902static void write_dev_flush(struct btrfs_device *device)
3903{
3904	struct bio *bio = &device->flush_bio;
3905
3906	device->last_flush_error = BLK_STS_OK;
 
 
 
 
 
 
 
 
 
 
 
 
 
3907
3908	bio_init(bio, device->bdev, NULL, 0,
3909		 REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH);
3910	bio->bi_end_io = btrfs_end_empty_barrier;
3911	init_completion(&device->flush_wait);
3912	bio->bi_private = &device->flush_wait;
 
 
3913	submit_bio(bio);
3914	set_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
3915}
3916
3917/*
3918 * If the flush bio has been submitted by write_dev_flush, wait for it.
3919 * Return true for any error, and false otherwise.
3920 */
3921static bool wait_dev_flush(struct btrfs_device *device)
3922{
3923	struct bio *bio = &device->flush_bio;
3924
3925	if (!test_and_clear_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state))
3926		return false;
3927
 
3928	wait_for_completion_io(&device->flush_wait);
3929
3930	if (bio->bi_status) {
3931		device->last_flush_error = bio->bi_status;
3932		btrfs_dev_stat_inc_and_print(device, BTRFS_DEV_STAT_FLUSH_ERRS);
3933		return true;
3934	}
3935
3936	return false;
 
 
 
 
3937}
3938
3939/*
3940 * send an empty flush down to each device in parallel,
3941 * then wait for them
3942 */
3943static int barrier_all_devices(struct btrfs_fs_info *info)
3944{
3945	struct list_head *head;
3946	struct btrfs_device *dev;
3947	int errors_wait = 0;
 
3948
3949	lockdep_assert_held(&info->fs_devices->device_list_mutex);
3950	/* send down all the barriers */
3951	head = &info->fs_devices->devices;
3952	list_for_each_entry(dev, head, dev_list) {
3953		if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
3954			continue;
3955		if (!dev->bdev)
3956			continue;
3957		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3958		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
3959			continue;
3960
3961		write_dev_flush(dev);
 
3962	}
3963
3964	/* wait for all the barriers */
3965	list_for_each_entry(dev, head, dev_list) {
3966		if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
3967			continue;
3968		if (!dev->bdev) {
3969			errors_wait++;
3970			continue;
3971		}
3972		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3973		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
3974			continue;
3975
3976		if (wait_dev_flush(dev))
 
 
 
 
3977			errors_wait++;
 
3978	}
3979
3980	/*
3981	 * Checks last_flush_error of disks in order to determine the device
3982	 * state.
3983	 */
3984	if (errors_wait && !btrfs_check_rw_degradable(info, NULL))
3985		return -EIO;
3986
 
3987	return 0;
3988}
3989
3990int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags)
3991{
3992	int raid_type;
3993	int min_tolerated = INT_MAX;
3994
3995	if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 ||
3996	    (flags & BTRFS_AVAIL_ALLOC_BIT_SINGLE))
3997		min_tolerated = min_t(int, min_tolerated,
3998				    btrfs_raid_array[BTRFS_RAID_SINGLE].
3999				    tolerated_failures);
4000
4001	for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
4002		if (raid_type == BTRFS_RAID_SINGLE)
4003			continue;
4004		if (!(flags & btrfs_raid_array[raid_type].bg_flag))
4005			continue;
4006		min_tolerated = min_t(int, min_tolerated,
4007				    btrfs_raid_array[raid_type].
4008				    tolerated_failures);
4009	}
4010
4011	if (min_tolerated == INT_MAX) {
4012		pr_warn("BTRFS: unknown raid flag: %llu", flags);
4013		min_tolerated = 0;
4014	}
4015
4016	return min_tolerated;
4017}
4018
4019int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors)
4020{
4021	struct list_head *head;
4022	struct btrfs_device *dev;
4023	struct btrfs_super_block *sb;
4024	struct btrfs_dev_item *dev_item;
4025	int ret;
4026	int do_barriers;
4027	int max_errors;
4028	int total_errors = 0;
4029	u64 flags;
4030
4031	do_barriers = !btrfs_test_opt(fs_info, NOBARRIER);
4032
4033	/*
4034	 * max_mirrors == 0 indicates we're from commit_transaction,
4035	 * not from fsync where the tree roots in fs_info have not
4036	 * been consistent on disk.
4037	 */
4038	if (max_mirrors == 0)
4039		backup_super_roots(fs_info);
4040
4041	sb = fs_info->super_for_commit;
4042	dev_item = &sb->dev_item;
4043
4044	mutex_lock(&fs_info->fs_devices->device_list_mutex);
4045	head = &fs_info->fs_devices->devices;
4046	max_errors = btrfs_super_num_devices(fs_info->super_copy) - 1;
4047
4048	if (do_barriers) {
4049		ret = barrier_all_devices(fs_info);
4050		if (ret) {
4051			mutex_unlock(
4052				&fs_info->fs_devices->device_list_mutex);
4053			btrfs_handle_fs_error(fs_info, ret,
4054					      "errors while submitting device barriers.");
4055			return ret;
4056		}
4057	}
4058
4059	list_for_each_entry(dev, head, dev_list) {
4060		if (!dev->bdev) {
4061			total_errors++;
4062			continue;
4063		}
4064		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4065		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4066			continue;
4067
4068		btrfs_set_stack_device_generation(dev_item, 0);
4069		btrfs_set_stack_device_type(dev_item, dev->type);
4070		btrfs_set_stack_device_id(dev_item, dev->devid);
4071		btrfs_set_stack_device_total_bytes(dev_item,
4072						   dev->commit_total_bytes);
4073		btrfs_set_stack_device_bytes_used(dev_item,
4074						  dev->commit_bytes_used);
4075		btrfs_set_stack_device_io_align(dev_item, dev->io_align);
4076		btrfs_set_stack_device_io_width(dev_item, dev->io_width);
4077		btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
4078		memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
4079		memcpy(dev_item->fsid, dev->fs_devices->metadata_uuid,
4080		       BTRFS_FSID_SIZE);
4081
4082		flags = btrfs_super_flags(sb);
4083		btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
4084
4085		ret = btrfs_validate_write_super(fs_info, sb);
4086		if (ret < 0) {
4087			mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4088			btrfs_handle_fs_error(fs_info, -EUCLEAN,
4089				"unexpected superblock corruption detected");
4090			return -EUCLEAN;
4091		}
4092
4093		ret = write_dev_supers(dev, sb, max_mirrors);
4094		if (ret)
4095			total_errors++;
4096	}
4097	if (total_errors > max_errors) {
4098		btrfs_err(fs_info, "%d errors while writing supers",
4099			  total_errors);
4100		mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4101
4102		/* FUA is masked off if unsupported and can't be the reason */
4103		btrfs_handle_fs_error(fs_info, -EIO,
4104				      "%d errors while writing supers",
4105				      total_errors);
4106		return -EIO;
4107	}
4108
4109	total_errors = 0;
4110	list_for_each_entry(dev, head, dev_list) {
4111		if (!dev->bdev)
4112			continue;
4113		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4114		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4115			continue;
4116
4117		ret = wait_dev_supers(dev, max_mirrors);
4118		if (ret)
4119			total_errors++;
4120	}
4121	mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4122	if (total_errors > max_errors) {
4123		btrfs_handle_fs_error(fs_info, -EIO,
4124				      "%d errors while writing supers",
4125				      total_errors);
4126		return -EIO;
4127	}
4128	return 0;
4129}
4130
4131/* Drop a fs root from the radix tree and free it. */
4132void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
4133				  struct btrfs_root *root)
4134{
4135	bool drop_ref = false;
4136
4137	spin_lock(&fs_info->fs_roots_radix_lock);
4138	radix_tree_delete(&fs_info->fs_roots_radix,
4139			  (unsigned long)root->root_key.objectid);
4140	if (test_and_clear_bit(BTRFS_ROOT_IN_RADIX, &root->state))
4141		drop_ref = true;
4142	spin_unlock(&fs_info->fs_roots_radix_lock);
4143
4144	if (BTRFS_FS_ERROR(fs_info)) {
4145		ASSERT(root->log_root == NULL);
4146		if (root->reloc_root) {
4147			btrfs_put_root(root->reloc_root);
4148			root->reloc_root = NULL;
4149		}
4150	}
4151
4152	if (drop_ref)
4153		btrfs_put_root(root);
4154}
4155
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4156int btrfs_commit_super(struct btrfs_fs_info *fs_info)
4157{
4158	struct btrfs_root *root = fs_info->tree_root;
4159	struct btrfs_trans_handle *trans;
4160
4161	mutex_lock(&fs_info->cleaner_mutex);
4162	btrfs_run_delayed_iputs(fs_info);
4163	mutex_unlock(&fs_info->cleaner_mutex);
4164	wake_up_process(fs_info->cleaner_kthread);
4165
4166	/* wait until ongoing cleanup work done */
4167	down_write(&fs_info->cleanup_work_sem);
4168	up_write(&fs_info->cleanup_work_sem);
4169
4170	trans = btrfs_join_transaction(root);
4171	if (IS_ERR(trans))
4172		return PTR_ERR(trans);
4173	return btrfs_commit_transaction(trans);
4174}
4175
4176static void warn_about_uncommitted_trans(struct btrfs_fs_info *fs_info)
4177{
4178	struct btrfs_transaction *trans;
4179	struct btrfs_transaction *tmp;
4180	bool found = false;
4181
4182	if (list_empty(&fs_info->trans_list))
4183		return;
4184
4185	/*
4186	 * This function is only called at the very end of close_ctree(),
4187	 * thus no other running transaction, no need to take trans_lock.
4188	 */
4189	ASSERT(test_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags));
4190	list_for_each_entry_safe(trans, tmp, &fs_info->trans_list, list) {
4191		struct extent_state *cached = NULL;
4192		u64 dirty_bytes = 0;
4193		u64 cur = 0;
4194		u64 found_start;
4195		u64 found_end;
4196
4197		found = true;
4198		while (find_first_extent_bit(&trans->dirty_pages, cur,
4199			&found_start, &found_end, EXTENT_DIRTY, &cached)) {
4200			dirty_bytes += found_end + 1 - found_start;
4201			cur = found_end + 1;
4202		}
4203		btrfs_warn(fs_info,
4204	"transaction %llu (with %llu dirty metadata bytes) is not committed",
4205			   trans->transid, dirty_bytes);
4206		btrfs_cleanup_one_transaction(trans, fs_info);
4207
4208		if (trans == fs_info->running_transaction)
4209			fs_info->running_transaction = NULL;
4210		list_del_init(&trans->list);
4211
4212		btrfs_put_transaction(trans);
4213		trace_btrfs_transaction_commit(fs_info);
4214	}
4215	ASSERT(!found);
4216}
4217
4218void __cold close_ctree(struct btrfs_fs_info *fs_info)
4219{
4220	int ret;
4221
4222	set_bit(BTRFS_FS_CLOSING_START, &fs_info->flags);
4223
4224	/*
4225	 * If we had UNFINISHED_DROPS we could still be processing them, so
4226	 * clear that bit and wake up relocation so it can stop.
4227	 * We must do this before stopping the block group reclaim task, because
4228	 * at btrfs_relocate_block_group() we wait for this bit, and after the
4229	 * wait we stop with -EINTR if btrfs_fs_closing() returns non-zero - we
4230	 * have just set BTRFS_FS_CLOSING_START, so btrfs_fs_closing() will
4231	 * return 1.
4232	 */
4233	btrfs_wake_unfinished_drop(fs_info);
4234
4235	/*
4236	 * We may have the reclaim task running and relocating a data block group,
4237	 * in which case it may create delayed iputs. So stop it before we park
4238	 * the cleaner kthread otherwise we can get new delayed iputs after
4239	 * parking the cleaner, and that can make the async reclaim task to hang
4240	 * if it's waiting for delayed iputs to complete, since the cleaner is
4241	 * parked and can not run delayed iputs - this will make us hang when
4242	 * trying to stop the async reclaim task.
4243	 */
4244	cancel_work_sync(&fs_info->reclaim_bgs_work);
4245	/*
4246	 * We don't want the cleaner to start new transactions, add more delayed
4247	 * iputs, etc. while we're closing. We can't use kthread_stop() yet
4248	 * because that frees the task_struct, and the transaction kthread might
4249	 * still try to wake up the cleaner.
4250	 */
4251	kthread_park(fs_info->cleaner_kthread);
4252
4253	/* wait for the qgroup rescan worker to stop */
4254	btrfs_qgroup_wait_for_completion(fs_info, false);
4255
4256	/* wait for the uuid_scan task to finish */
4257	down(&fs_info->uuid_tree_rescan_sem);
4258	/* avoid complains from lockdep et al., set sem back to initial state */
4259	up(&fs_info->uuid_tree_rescan_sem);
4260
4261	/* pause restriper - we want to resume on mount */
4262	btrfs_pause_balance(fs_info);
4263
4264	btrfs_dev_replace_suspend_for_unmount(fs_info);
4265
4266	btrfs_scrub_cancel(fs_info);
4267
4268	/* wait for any defraggers to finish */
4269	wait_event(fs_info->transaction_wait,
4270		   (atomic_read(&fs_info->defrag_running) == 0));
4271
4272	/* clear out the rbtree of defraggable inodes */
4273	btrfs_cleanup_defrag_inodes(fs_info);
4274
4275	/*
4276	 * After we parked the cleaner kthread, ordered extents may have
4277	 * completed and created new delayed iputs. If one of the async reclaim
4278	 * tasks is running and in the RUN_DELAYED_IPUTS flush state, then we
4279	 * can hang forever trying to stop it, because if a delayed iput is
4280	 * added after it ran btrfs_run_delayed_iputs() and before it called
4281	 * btrfs_wait_on_delayed_iputs(), it will hang forever since there is
4282	 * no one else to run iputs.
4283	 *
4284	 * So wait for all ongoing ordered extents to complete and then run
4285	 * delayed iputs. This works because once we reach this point no one
4286	 * can either create new ordered extents nor create delayed iputs
4287	 * through some other means.
4288	 *
4289	 * Also note that btrfs_wait_ordered_roots() is not safe here, because
4290	 * it waits for BTRFS_ORDERED_COMPLETE to be set on an ordered extent,
4291	 * but the delayed iput for the respective inode is made only when doing
4292	 * the final btrfs_put_ordered_extent() (which must happen at
4293	 * btrfs_finish_ordered_io() when we are unmounting).
4294	 */
4295	btrfs_flush_workqueue(fs_info->endio_write_workers);
4296	/* Ordered extents for free space inodes. */
4297	btrfs_flush_workqueue(fs_info->endio_freespace_worker);
4298	btrfs_run_delayed_iputs(fs_info);
4299
4300	cancel_work_sync(&fs_info->async_reclaim_work);
4301	cancel_work_sync(&fs_info->async_data_reclaim_work);
4302	cancel_work_sync(&fs_info->preempt_reclaim_work);
4303
4304	/* Cancel or finish ongoing discard work */
4305	btrfs_discard_cleanup(fs_info);
4306
4307	if (!sb_rdonly(fs_info->sb)) {
4308		/*
4309		 * The cleaner kthread is stopped, so do one final pass over
4310		 * unused block groups.
4311		 */
4312		btrfs_delete_unused_bgs(fs_info);
4313
4314		/*
4315		 * There might be existing delayed inode workers still running
4316		 * and holding an empty delayed inode item. We must wait for
4317		 * them to complete first because they can create a transaction.
4318		 * This happens when someone calls btrfs_balance_delayed_items()
4319		 * and then a transaction commit runs the same delayed nodes
4320		 * before any delayed worker has done something with the nodes.
4321		 * We must wait for any worker here and not at transaction
4322		 * commit time since that could cause a deadlock.
4323		 * This is a very rare case.
4324		 */
4325		btrfs_flush_workqueue(fs_info->delayed_workers);
4326
4327		ret = btrfs_commit_super(fs_info);
4328		if (ret)
4329			btrfs_err(fs_info, "commit super ret %d", ret);
4330	}
4331
4332	if (BTRFS_FS_ERROR(fs_info))
4333		btrfs_error_commit_super(fs_info);
4334
4335	kthread_stop(fs_info->transaction_kthread);
4336	kthread_stop(fs_info->cleaner_kthread);
4337
4338	ASSERT(list_empty(&fs_info->delayed_iputs));
4339	set_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags);
4340
4341	if (btrfs_check_quota_leak(fs_info)) {
4342		WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
4343		btrfs_err(fs_info, "qgroup reserved space leaked");
4344	}
4345
4346	btrfs_free_qgroup_config(fs_info);
4347	ASSERT(list_empty(&fs_info->delalloc_roots));
4348
4349	if (percpu_counter_sum(&fs_info->delalloc_bytes)) {
4350		btrfs_info(fs_info, "at unmount delalloc count %lld",
4351		       percpu_counter_sum(&fs_info->delalloc_bytes));
4352	}
4353
4354	if (percpu_counter_sum(&fs_info->ordered_bytes))
4355		btrfs_info(fs_info, "at unmount dio bytes count %lld",
4356			   percpu_counter_sum(&fs_info->ordered_bytes));
4357
4358	btrfs_sysfs_remove_mounted(fs_info);
4359	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
4360
4361	btrfs_put_block_group_cache(fs_info);
4362
4363	/*
4364	 * we must make sure there is not any read request to
4365	 * submit after we stopping all workers.
4366	 */
4367	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
4368	btrfs_stop_all_workers(fs_info);
4369
4370	/* We shouldn't have any transaction open at this point */
4371	warn_about_uncommitted_trans(fs_info);
4372
4373	clear_bit(BTRFS_FS_OPEN, &fs_info->flags);
4374	free_root_pointers(fs_info, true);
4375	btrfs_free_fs_roots(fs_info);
4376
4377	/*
4378	 * We must free the block groups after dropping the fs_roots as we could
4379	 * have had an IO error and have left over tree log blocks that aren't
4380	 * cleaned up until the fs roots are freed.  This makes the block group
4381	 * accounting appear to be wrong because there's pending reserved bytes,
4382	 * so make sure we do the block group cleanup afterwards.
4383	 */
4384	btrfs_free_block_groups(fs_info);
4385
4386	iput(fs_info->btree_inode);
4387
4388	btrfs_mapping_tree_free(fs_info);
 
 
 
 
 
4389	btrfs_close_devices(fs_info->fs_devices);
4390}
4391
4392void btrfs_mark_buffer_dirty(struct btrfs_trans_handle *trans,
4393			     struct extent_buffer *buf)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4394{
4395	struct btrfs_fs_info *fs_info = buf->fs_info;
4396	u64 transid = btrfs_header_generation(buf);
 
4397
4398#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4399	/*
4400	 * This is a fast path so only do this check if we have sanity tests
4401	 * enabled.  Normal people shouldn't be using unmapped buffers as dirty
4402	 * outside of the sanity tests.
4403	 */
4404	if (unlikely(test_bit(EXTENT_BUFFER_UNMAPPED, &buf->bflags)))
4405		return;
4406#endif
4407	/* This is an active transaction (its state < TRANS_STATE_UNBLOCKED). */
4408	ASSERT(trans->transid == fs_info->generation);
4409	btrfs_assert_tree_write_locked(buf);
4410	if (unlikely(transid != fs_info->generation)) {
4411		btrfs_abort_transaction(trans, -EUCLEAN);
4412		btrfs_crit(fs_info,
4413"dirty buffer transid mismatch, logical %llu found transid %llu running transid %llu",
4414			   buf->start, transid, fs_info->generation);
 
 
 
 
 
 
 
 
 
 
 
 
 
4415	}
4416	set_extent_buffer_dirty(buf);
4417}
4418
4419static void __btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info,
4420					int flush_delayed)
4421{
4422	/*
4423	 * looks as though older kernels can get into trouble with
4424	 * this code, they end up stuck in balance_dirty_pages forever
4425	 */
4426	int ret;
4427
4428	if (current->flags & PF_MEMALLOC)
4429		return;
4430
4431	if (flush_delayed)
4432		btrfs_balance_delayed_items(fs_info);
4433
4434	ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
4435				     BTRFS_DIRTY_METADATA_THRESH,
4436				     fs_info->dirty_metadata_batch);
4437	if (ret > 0) {
4438		balance_dirty_pages_ratelimited(fs_info->btree_inode->i_mapping);
4439	}
4440}
4441
4442void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info)
4443{
4444	__btrfs_btree_balance_dirty(fs_info, 1);
4445}
4446
4447void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info)
4448{
4449	__btrfs_btree_balance_dirty(fs_info, 0);
4450}
4451
4452static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info)
4453{
4454	/* cleanup FS via transaction */
4455	btrfs_cleanup_transaction(fs_info);
4456
4457	mutex_lock(&fs_info->cleaner_mutex);
4458	btrfs_run_delayed_iputs(fs_info);
4459	mutex_unlock(&fs_info->cleaner_mutex);
4460
4461	down_write(&fs_info->cleanup_work_sem);
4462	up_write(&fs_info->cleanup_work_sem);
4463}
4464
4465static void btrfs_drop_all_logs(struct btrfs_fs_info *fs_info)
4466{
4467	struct btrfs_root *gang[8];
4468	u64 root_objectid = 0;
4469	int ret;
4470
4471	spin_lock(&fs_info->fs_roots_radix_lock);
4472	while ((ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
4473					     (void **)gang, root_objectid,
4474					     ARRAY_SIZE(gang))) != 0) {
4475		int i;
4476
4477		for (i = 0; i < ret; i++)
4478			gang[i] = btrfs_grab_root(gang[i]);
4479		spin_unlock(&fs_info->fs_roots_radix_lock);
4480
4481		for (i = 0; i < ret; i++) {
4482			if (!gang[i])
4483				continue;
4484			root_objectid = gang[i]->root_key.objectid;
4485			btrfs_free_log(NULL, gang[i]);
4486			btrfs_put_root(gang[i]);
4487		}
4488		root_objectid++;
4489		spin_lock(&fs_info->fs_roots_radix_lock);
4490	}
4491	spin_unlock(&fs_info->fs_roots_radix_lock);
4492	btrfs_free_log_root_tree(NULL, fs_info);
4493}
4494
4495static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
4496{
4497	struct btrfs_ordered_extent *ordered;
4498
4499	spin_lock(&root->ordered_extent_lock);
4500	/*
4501	 * This will just short circuit the ordered completion stuff which will
4502	 * make sure the ordered extent gets properly cleaned up.
4503	 */
4504	list_for_each_entry(ordered, &root->ordered_extents,
4505			    root_extent_list)
4506		set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
4507	spin_unlock(&root->ordered_extent_lock);
4508}
4509
4510static void btrfs_destroy_all_ordered_extents(struct btrfs_fs_info *fs_info)
4511{
4512	struct btrfs_root *root;
4513	LIST_HEAD(splice);
 
 
4514
4515	spin_lock(&fs_info->ordered_root_lock);
4516	list_splice_init(&fs_info->ordered_roots, &splice);
4517	while (!list_empty(&splice)) {
4518		root = list_first_entry(&splice, struct btrfs_root,
4519					ordered_root);
4520		list_move_tail(&root->ordered_root,
4521			       &fs_info->ordered_roots);
4522
4523		spin_unlock(&fs_info->ordered_root_lock);
4524		btrfs_destroy_ordered_extents(root);
4525
4526		cond_resched();
4527		spin_lock(&fs_info->ordered_root_lock);
4528	}
4529	spin_unlock(&fs_info->ordered_root_lock);
4530
4531	/*
4532	 * We need this here because if we've been flipped read-only we won't
4533	 * get sync() from the umount, so we need to make sure any ordered
4534	 * extents that haven't had their dirty pages IO start writeout yet
4535	 * actually get run and error out properly.
4536	 */
4537	btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
4538}
4539
4540static void btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
4541				       struct btrfs_fs_info *fs_info)
4542{
4543	struct rb_node *node;
4544	struct btrfs_delayed_ref_root *delayed_refs;
4545	struct btrfs_delayed_ref_node *ref;
 
4546
4547	delayed_refs = &trans->delayed_refs;
4548
4549	spin_lock(&delayed_refs->lock);
4550	if (atomic_read(&delayed_refs->num_entries) == 0) {
4551		spin_unlock(&delayed_refs->lock);
4552		btrfs_debug(fs_info, "delayed_refs has NO entry");
4553		return;
4554	}
4555
4556	while ((node = rb_first_cached(&delayed_refs->href_root)) != NULL) {
4557		struct btrfs_delayed_ref_head *head;
4558		struct rb_node *n;
4559		bool pin_bytes = false;
4560
4561		head = rb_entry(node, struct btrfs_delayed_ref_head,
4562				href_node);
4563		if (btrfs_delayed_ref_lock(delayed_refs, head))
4564			continue;
4565
4566		spin_lock(&head->lock);
4567		while ((n = rb_first_cached(&head->ref_tree)) != NULL) {
4568			ref = rb_entry(n, struct btrfs_delayed_ref_node,
4569				       ref_node);
 
4570			rb_erase_cached(&ref->ref_node, &head->ref_tree);
4571			RB_CLEAR_NODE(&ref->ref_node);
4572			if (!list_empty(&ref->add_list))
4573				list_del(&ref->add_list);
4574			atomic_dec(&delayed_refs->num_entries);
4575			btrfs_put_delayed_ref(ref);
4576			btrfs_delayed_refs_rsv_release(fs_info, 1, 0);
4577		}
4578		if (head->must_insert_reserved)
4579			pin_bytes = true;
4580		btrfs_free_delayed_extent_op(head->extent_op);
4581		btrfs_delete_ref_head(delayed_refs, head);
4582		spin_unlock(&head->lock);
4583		spin_unlock(&delayed_refs->lock);
4584		mutex_unlock(&head->mutex);
4585
4586		if (pin_bytes) {
4587			struct btrfs_block_group *cache;
4588
4589			cache = btrfs_lookup_block_group(fs_info, head->bytenr);
4590			BUG_ON(!cache);
4591
4592			spin_lock(&cache->space_info->lock);
4593			spin_lock(&cache->lock);
4594			cache->pinned += head->num_bytes;
4595			btrfs_space_info_update_bytes_pinned(fs_info,
4596				cache->space_info, head->num_bytes);
4597			cache->reserved -= head->num_bytes;
4598			cache->space_info->bytes_reserved -= head->num_bytes;
4599			spin_unlock(&cache->lock);
4600			spin_unlock(&cache->space_info->lock);
4601
4602			btrfs_put_block_group(cache);
4603
4604			btrfs_error_unpin_extent_range(fs_info, head->bytenr,
4605				head->bytenr + head->num_bytes - 1);
4606		}
4607		btrfs_cleanup_ref_head_accounting(fs_info, delayed_refs, head);
4608		btrfs_put_delayed_ref_head(head);
4609		cond_resched();
4610		spin_lock(&delayed_refs->lock);
4611	}
4612	btrfs_qgroup_destroy_extent_records(trans);
4613
4614	spin_unlock(&delayed_refs->lock);
 
 
4615}
4616
4617static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
4618{
4619	struct btrfs_inode *btrfs_inode;
4620	LIST_HEAD(splice);
 
 
4621
4622	spin_lock(&root->delalloc_lock);
4623	list_splice_init(&root->delalloc_inodes, &splice);
4624
4625	while (!list_empty(&splice)) {
4626		struct inode *inode = NULL;
4627		btrfs_inode = list_first_entry(&splice, struct btrfs_inode,
4628					       delalloc_inodes);
4629		__btrfs_del_delalloc_inode(root, btrfs_inode);
4630		spin_unlock(&root->delalloc_lock);
4631
4632		/*
4633		 * Make sure we get a live inode and that it'll not disappear
4634		 * meanwhile.
4635		 */
4636		inode = igrab(&btrfs_inode->vfs_inode);
4637		if (inode) {
4638			unsigned int nofs_flag;
4639
4640			nofs_flag = memalloc_nofs_save();
4641			invalidate_inode_pages2(inode->i_mapping);
4642			memalloc_nofs_restore(nofs_flag);
4643			iput(inode);
4644		}
4645		spin_lock(&root->delalloc_lock);
4646	}
4647	spin_unlock(&root->delalloc_lock);
4648}
4649
4650static void btrfs_destroy_all_delalloc_inodes(struct btrfs_fs_info *fs_info)
4651{
4652	struct btrfs_root *root;
4653	LIST_HEAD(splice);
 
 
4654
4655	spin_lock(&fs_info->delalloc_root_lock);
4656	list_splice_init(&fs_info->delalloc_roots, &splice);
4657	while (!list_empty(&splice)) {
4658		root = list_first_entry(&splice, struct btrfs_root,
4659					 delalloc_root);
4660		root = btrfs_grab_root(root);
4661		BUG_ON(!root);
4662		spin_unlock(&fs_info->delalloc_root_lock);
4663
4664		btrfs_destroy_delalloc_inodes(root);
4665		btrfs_put_root(root);
4666
4667		spin_lock(&fs_info->delalloc_root_lock);
4668	}
4669	spin_unlock(&fs_info->delalloc_root_lock);
4670}
4671
4672static void btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
4673					 struct extent_io_tree *dirty_pages,
4674					 int mark)
4675{
 
4676	struct extent_buffer *eb;
4677	u64 start = 0;
4678	u64 end;
4679
4680	while (find_first_extent_bit(dirty_pages, start, &start, &end,
4681				     mark, NULL)) {
 
 
 
 
4682		clear_extent_bits(dirty_pages, start, end, mark);
4683		while (start <= end) {
4684			eb = find_extent_buffer(fs_info, start);
4685			start += fs_info->nodesize;
4686			if (!eb)
4687				continue;
4688
4689			btrfs_tree_lock(eb);
4690			wait_on_extent_buffer_writeback(eb);
4691			btrfs_clear_buffer_dirty(NULL, eb);
4692			btrfs_tree_unlock(eb);
4693
 
 
 
4694			free_extent_buffer_stale(eb);
4695		}
4696	}
 
 
4697}
4698
4699static void btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
4700					struct extent_io_tree *unpin)
4701{
4702	u64 start;
4703	u64 end;
 
4704
4705	while (1) {
4706		struct extent_state *cached_state = NULL;
4707
4708		/*
4709		 * The btrfs_finish_extent_commit() may get the same range as
4710		 * ours between find_first_extent_bit and clear_extent_dirty.
4711		 * Hence, hold the unused_bg_unpin_mutex to avoid double unpin
4712		 * the same extent range.
4713		 */
4714		mutex_lock(&fs_info->unused_bg_unpin_mutex);
4715		if (!find_first_extent_bit(unpin, 0, &start, &end,
4716					   EXTENT_DIRTY, &cached_state)) {
 
4717			mutex_unlock(&fs_info->unused_bg_unpin_mutex);
4718			break;
4719		}
4720
4721		clear_extent_dirty(unpin, start, end, &cached_state);
4722		free_extent_state(cached_state);
4723		btrfs_error_unpin_extent_range(fs_info, start, end);
4724		mutex_unlock(&fs_info->unused_bg_unpin_mutex);
4725		cond_resched();
4726	}
 
 
4727}
4728
4729static void btrfs_cleanup_bg_io(struct btrfs_block_group *cache)
4730{
4731	struct inode *inode;
4732
4733	inode = cache->io_ctl.inode;
4734	if (inode) {
4735		unsigned int nofs_flag;
4736
4737		nofs_flag = memalloc_nofs_save();
4738		invalidate_inode_pages2(inode->i_mapping);
4739		memalloc_nofs_restore(nofs_flag);
4740
4741		BTRFS_I(inode)->generation = 0;
4742		cache->io_ctl.inode = NULL;
4743		iput(inode);
4744	}
4745	ASSERT(cache->io_ctl.pages == NULL);
4746	btrfs_put_block_group(cache);
4747}
4748
4749void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *cur_trans,
4750			     struct btrfs_fs_info *fs_info)
4751{
4752	struct btrfs_block_group *cache;
4753
4754	spin_lock(&cur_trans->dirty_bgs_lock);
4755	while (!list_empty(&cur_trans->dirty_bgs)) {
4756		cache = list_first_entry(&cur_trans->dirty_bgs,
4757					 struct btrfs_block_group,
4758					 dirty_list);
4759
4760		if (!list_empty(&cache->io_list)) {
4761			spin_unlock(&cur_trans->dirty_bgs_lock);
4762			list_del_init(&cache->io_list);
4763			btrfs_cleanup_bg_io(cache);
4764			spin_lock(&cur_trans->dirty_bgs_lock);
4765		}
4766
4767		list_del_init(&cache->dirty_list);
4768		spin_lock(&cache->lock);
4769		cache->disk_cache_state = BTRFS_DC_ERROR;
4770		spin_unlock(&cache->lock);
4771
4772		spin_unlock(&cur_trans->dirty_bgs_lock);
4773		btrfs_put_block_group(cache);
4774		btrfs_dec_delayed_refs_rsv_bg_updates(fs_info);
4775		spin_lock(&cur_trans->dirty_bgs_lock);
4776	}
4777	spin_unlock(&cur_trans->dirty_bgs_lock);
4778
4779	/*
4780	 * Refer to the definition of io_bgs member for details why it's safe
4781	 * to use it without any locking
4782	 */
4783	while (!list_empty(&cur_trans->io_bgs)) {
4784		cache = list_first_entry(&cur_trans->io_bgs,
4785					 struct btrfs_block_group,
4786					 io_list);
4787
4788		list_del_init(&cache->io_list);
4789		spin_lock(&cache->lock);
4790		cache->disk_cache_state = BTRFS_DC_ERROR;
4791		spin_unlock(&cache->lock);
4792		btrfs_cleanup_bg_io(cache);
4793	}
4794}
4795
4796static void btrfs_free_all_qgroup_pertrans(struct btrfs_fs_info *fs_info)
4797{
4798	struct btrfs_root *gang[8];
4799	int i;
4800	int ret;
4801
4802	spin_lock(&fs_info->fs_roots_radix_lock);
4803	while (1) {
4804		ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix,
4805						 (void **)gang, 0,
4806						 ARRAY_SIZE(gang),
4807						 BTRFS_ROOT_TRANS_TAG);
4808		if (ret == 0)
4809			break;
4810		for (i = 0; i < ret; i++) {
4811			struct btrfs_root *root = gang[i];
4812
4813			btrfs_qgroup_free_meta_all_pertrans(root);
4814			radix_tree_tag_clear(&fs_info->fs_roots_radix,
4815					(unsigned long)root->root_key.objectid,
4816					BTRFS_ROOT_TRANS_TAG);
4817		}
4818	}
4819	spin_unlock(&fs_info->fs_roots_radix_lock);
4820}
4821
4822void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
4823				   struct btrfs_fs_info *fs_info)
4824{
4825	struct btrfs_device *dev, *tmp;
4826
4827	btrfs_cleanup_dirty_bgs(cur_trans, fs_info);
4828	ASSERT(list_empty(&cur_trans->dirty_bgs));
4829	ASSERT(list_empty(&cur_trans->io_bgs));
4830
4831	list_for_each_entry_safe(dev, tmp, &cur_trans->dev_update_list,
4832				 post_commit_list) {
4833		list_del_init(&dev->post_commit_list);
4834	}
4835
4836	btrfs_destroy_delayed_refs(cur_trans, fs_info);
4837
4838	cur_trans->state = TRANS_STATE_COMMIT_START;
4839	wake_up(&fs_info->transaction_blocked_wait);
4840
4841	cur_trans->state = TRANS_STATE_UNBLOCKED;
4842	wake_up(&fs_info->transaction_wait);
4843
4844	btrfs_destroy_delayed_inodes(fs_info);
4845
4846	btrfs_destroy_marked_extents(fs_info, &cur_trans->dirty_pages,
4847				     EXTENT_DIRTY);
4848	btrfs_destroy_pinned_extent(fs_info, &cur_trans->pinned_extents);
4849
4850	btrfs_free_all_qgroup_pertrans(fs_info);
4851
4852	cur_trans->state =TRANS_STATE_COMPLETED;
4853	wake_up(&cur_trans->commit_wait);
4854}
4855
4856static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info)
4857{
4858	struct btrfs_transaction *t;
4859
4860	mutex_lock(&fs_info->transaction_kthread_mutex);
4861
4862	spin_lock(&fs_info->trans_lock);
4863	while (!list_empty(&fs_info->trans_list)) {
4864		t = list_first_entry(&fs_info->trans_list,
4865				     struct btrfs_transaction, list);
4866		if (t->state >= TRANS_STATE_COMMIT_PREP) {
4867			refcount_inc(&t->use_count);
4868			spin_unlock(&fs_info->trans_lock);
4869			btrfs_wait_for_commit(fs_info, t->transid);
4870			btrfs_put_transaction(t);
4871			spin_lock(&fs_info->trans_lock);
4872			continue;
4873		}
4874		if (t == fs_info->running_transaction) {
4875			t->state = TRANS_STATE_COMMIT_DOING;
4876			spin_unlock(&fs_info->trans_lock);
4877			/*
4878			 * We wait for 0 num_writers since we don't hold a trans
4879			 * handle open currently for this transaction.
4880			 */
4881			wait_event(t->writer_wait,
4882				   atomic_read(&t->num_writers) == 0);
4883		} else {
4884			spin_unlock(&fs_info->trans_lock);
4885		}
4886		btrfs_cleanup_one_transaction(t, fs_info);
4887
4888		spin_lock(&fs_info->trans_lock);
4889		if (t == fs_info->running_transaction)
4890			fs_info->running_transaction = NULL;
4891		list_del_init(&t->list);
4892		spin_unlock(&fs_info->trans_lock);
4893
4894		btrfs_put_transaction(t);
4895		trace_btrfs_transaction_commit(fs_info);
4896		spin_lock(&fs_info->trans_lock);
4897	}
4898	spin_unlock(&fs_info->trans_lock);
4899	btrfs_destroy_all_ordered_extents(fs_info);
4900	btrfs_destroy_delayed_inodes(fs_info);
4901	btrfs_assert_delayed_root_empty(fs_info);
4902	btrfs_destroy_all_delalloc_inodes(fs_info);
4903	btrfs_drop_all_logs(fs_info);
4904	mutex_unlock(&fs_info->transaction_kthread_mutex);
4905
4906	return 0;
4907}
4908
4909int btrfs_init_root_free_objectid(struct btrfs_root *root)
4910{
4911	struct btrfs_path *path;
4912	int ret;
4913	struct extent_buffer *l;
4914	struct btrfs_key search_key;
4915	struct btrfs_key found_key;
4916	int slot;
4917
4918	path = btrfs_alloc_path();
4919	if (!path)
4920		return -ENOMEM;
4921
4922	search_key.objectid = BTRFS_LAST_FREE_OBJECTID;
4923	search_key.type = -1;
4924	search_key.offset = (u64)-1;
4925	ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
4926	if (ret < 0)
4927		goto error;
4928	BUG_ON(ret == 0); /* Corruption */
4929	if (path->slots[0] > 0) {
4930		slot = path->slots[0] - 1;
4931		l = path->nodes[0];
4932		btrfs_item_key_to_cpu(l, &found_key, slot);
4933		root->free_objectid = max_t(u64, found_key.objectid + 1,
4934					    BTRFS_FIRST_FREE_OBJECTID);
4935	} else {
4936		root->free_objectid = BTRFS_FIRST_FREE_OBJECTID;
4937	}
4938	ret = 0;
4939error:
4940	btrfs_free_path(path);
4941	return ret;
4942}
4943
4944int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid)
4945{
4946	int ret;
4947	mutex_lock(&root->objectid_mutex);
4948
4949	if (unlikely(root->free_objectid >= BTRFS_LAST_FREE_OBJECTID)) {
4950		btrfs_warn(root->fs_info,
4951			   "the objectid of root %llu reaches its highest value",
4952			   root->root_key.objectid);
4953		ret = -ENOSPC;
4954		goto out;
4955	}
4956
4957	*objectid = root->free_objectid++;
4958	ret = 0;
4959out:
4960	mutex_unlock(&root->objectid_mutex);
4961	return ret;
4962}
v6.2
   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 <asm/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 "check-integrity.h"
  33#include "rcu-string.h"
  34#include "dev-replace.h"
  35#include "raid56.h"
  36#include "sysfs.h"
  37#include "qgroup.h"
  38#include "compression.h"
  39#include "tree-checker.h"
  40#include "ref-verify.h"
  41#include "block-group.h"
  42#include "discard.h"
  43#include "space-info.h"
  44#include "zoned.h"
  45#include "subpage.h"
  46#include "fs.h"
  47#include "accessors.h"
  48#include "extent-tree.h"
  49#include "root-tree.h"
  50#include "defrag.h"
  51#include "uuid-tree.h"
  52#include "relocation.h"
  53#include "scrub.h"
  54#include "super.h"
  55
  56#define BTRFS_SUPER_FLAG_SUPP	(BTRFS_HEADER_FLAG_WRITTEN |\
  57				 BTRFS_HEADER_FLAG_RELOC |\
  58				 BTRFS_SUPER_FLAG_ERROR |\
  59				 BTRFS_SUPER_FLAG_SEEDING |\
  60				 BTRFS_SUPER_FLAG_METADUMP |\
  61				 BTRFS_SUPER_FLAG_METADUMP_V2)
  62
  63static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
  64static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
  65				      struct btrfs_fs_info *fs_info);
  66static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
  67static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
  68					struct extent_io_tree *dirty_pages,
  69					int mark);
  70static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
  71				       struct extent_io_tree *pinned_extents);
  72static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info);
  73static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info);
  74
  75static void btrfs_free_csum_hash(struct btrfs_fs_info *fs_info)
  76{
  77	if (fs_info->csum_shash)
  78		crypto_free_shash(fs_info->csum_shash);
  79}
  80
  81/*
  82 * async submit bios are used to offload expensive checksumming
  83 * onto the worker threads.  They checksum file and metadata bios
  84 * just before they are sent down the IO stack.
  85 */
  86struct async_submit_bio {
  87	struct btrfs_inode *inode;
  88	struct bio *bio;
  89	enum btrfs_wq_submit_cmd submit_cmd;
  90	int mirror_num;
  91
  92	/* Optional parameter for used by direct io */
  93	u64 dio_file_offset;
  94	struct btrfs_work work;
  95	blk_status_t status;
  96};
  97
  98/*
  99 * Compute the csum of a btree block and store the result to provided buffer.
 100 */
 101static void csum_tree_block(struct extent_buffer *buf, u8 *result)
 102{
 103	struct btrfs_fs_info *fs_info = buf->fs_info;
 104	const int num_pages = num_extent_pages(buf);
 105	const int first_page_part = min_t(u32, PAGE_SIZE, fs_info->nodesize);
 106	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 107	char *kaddr;
 108	int i;
 109
 110	shash->tfm = fs_info->csum_shash;
 111	crypto_shash_init(shash);
 112	kaddr = page_address(buf->pages[0]) + offset_in_page(buf->start);
 
 
 
 
 
 
 
 
 
 
 
 113	crypto_shash_update(shash, kaddr + BTRFS_CSUM_SIZE,
 114			    first_page_part - BTRFS_CSUM_SIZE);
 115
 116	for (i = 1; i < num_pages; i++) {
 117		kaddr = page_address(buf->pages[i]);
 
 
 
 
 
 
 118		crypto_shash_update(shash, kaddr, PAGE_SIZE);
 119	}
 120	memset(result, 0, BTRFS_CSUM_SIZE);
 121	crypto_shash_final(shash, result);
 122}
 123
 124/*
 125 * we can't consider a given block up to date unless the transid of the
 126 * block matches the transid in the parent node's pointer.  This is how we
 127 * detect blocks that either didn't get written at all or got written
 128 * in the wrong place.
 129 */
 130static int verify_parent_transid(struct extent_io_tree *io_tree,
 131				 struct extent_buffer *eb, u64 parent_transid,
 132				 int atomic)
 133{
 134	struct extent_state *cached_state = NULL;
 135	int ret;
 136
 137	if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 138		return 0;
 139
 140	if (atomic)
 141		return -EAGAIN;
 142
 143	lock_extent(io_tree, eb->start, eb->start + eb->len - 1, &cached_state);
 144	if (extent_buffer_uptodate(eb) &&
 145	    btrfs_header_generation(eb) == parent_transid) {
 146		ret = 0;
 147		goto out;
 148	}
 149	btrfs_err_rl(eb->fs_info,
 150"parent transid verify failed on logical %llu mirror %u wanted %llu found %llu",
 151			eb->start, eb->read_mirror,
 152			parent_transid, btrfs_header_generation(eb));
 153	ret = 1;
 154	clear_extent_buffer_uptodate(eb);
 155out:
 156	unlock_extent(io_tree, eb->start, eb->start + eb->len - 1,
 157		      &cached_state);
 158	return ret;
 159}
 160
 161static bool btrfs_supported_super_csum(u16 csum_type)
 162{
 163	switch (csum_type) {
 164	case BTRFS_CSUM_TYPE_CRC32:
 165	case BTRFS_CSUM_TYPE_XXHASH:
 166	case BTRFS_CSUM_TYPE_SHA256:
 167	case BTRFS_CSUM_TYPE_BLAKE2:
 168		return true;
 169	default:
 170		return false;
 171	}
 172}
 173
 174/*
 175 * Return 0 if the superblock checksum type matches the checksum value of that
 176 * algorithm. Pass the raw disk superblock data.
 177 */
 178int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
 179			   const struct btrfs_super_block *disk_sb)
 180{
 181	char result[BTRFS_CSUM_SIZE];
 182	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 183
 184	shash->tfm = fs_info->csum_shash;
 185
 186	/*
 187	 * The super_block structure does not span the whole
 188	 * BTRFS_SUPER_INFO_SIZE range, we expect that the unused space is
 189	 * filled with zeros and is included in the checksum.
 190	 */
 191	crypto_shash_digest(shash, (const u8 *)disk_sb + BTRFS_CSUM_SIZE,
 192			    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE, result);
 193
 194	if (memcmp(disk_sb->csum, result, fs_info->csum_size))
 195		return 1;
 196
 197	return 0;
 198}
 199
 200int btrfs_verify_level_key(struct extent_buffer *eb, int level,
 201			   struct btrfs_key *first_key, u64 parent_transid)
 202{
 203	struct btrfs_fs_info *fs_info = eb->fs_info;
 204	int found_level;
 205	struct btrfs_key found_key;
 206	int ret;
 207
 208	found_level = btrfs_header_level(eb);
 209	if (found_level != level) {
 210		WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
 211		     KERN_ERR "BTRFS: tree level check failed\n");
 212		btrfs_err(fs_info,
 213"tree level mismatch detected, bytenr=%llu level expected=%u has=%u",
 214			  eb->start, level, found_level);
 215		return -EIO;
 216	}
 217
 218	if (!first_key)
 219		return 0;
 220
 221	/*
 222	 * For live tree block (new tree blocks in current transaction),
 223	 * we need proper lock context to avoid race, which is impossible here.
 224	 * So we only checks tree blocks which is read from disk, whose
 225	 * generation <= fs_info->last_trans_committed.
 226	 */
 227	if (btrfs_header_generation(eb) > fs_info->last_trans_committed)
 228		return 0;
 229
 230	/* We have @first_key, so this @eb must have at least one item */
 231	if (btrfs_header_nritems(eb) == 0) {
 232		btrfs_err(fs_info,
 233		"invalid tree nritems, bytenr=%llu nritems=0 expect >0",
 234			  eb->start);
 235		WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
 236		return -EUCLEAN;
 237	}
 238
 239	if (found_level)
 240		btrfs_node_key_to_cpu(eb, &found_key, 0);
 241	else
 242		btrfs_item_key_to_cpu(eb, &found_key, 0);
 243	ret = btrfs_comp_cpu_keys(first_key, &found_key);
 244
 245	if (ret) {
 246		WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
 247		     KERN_ERR "BTRFS: tree first key check failed\n");
 248		btrfs_err(fs_info,
 249"tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
 250			  eb->start, parent_transid, first_key->objectid,
 251			  first_key->type, first_key->offset,
 252			  found_key.objectid, found_key.type,
 253			  found_key.offset);
 254	}
 255	return ret;
 256}
 257
 258static int btrfs_repair_eb_io_failure(const struct extent_buffer *eb,
 259				      int mirror_num)
 260{
 261	struct btrfs_fs_info *fs_info = eb->fs_info;
 262	u64 start = eb->start;
 263	int i, num_pages = num_extent_pages(eb);
 264	int ret = 0;
 265
 266	if (sb_rdonly(fs_info->sb))
 267		return -EROFS;
 268
 269	for (i = 0; i < num_pages; i++) {
 270		struct page *p = eb->pages[i];
 271
 272		ret = btrfs_repair_io_failure(fs_info, 0, start, PAGE_SIZE,
 273				start, p, start - page_offset(p), mirror_num);
 
 
 
 
 
 274		if (ret)
 275			break;
 276		start += PAGE_SIZE;
 277	}
 278
 279	return ret;
 280}
 281
 282/*
 283 * helper to read a given tree block, doing retries as required when
 284 * the checksums don't match and we have alternate mirrors to try.
 285 *
 286 * @check:		expected tree parentness check, see the comments of the
 287 *			structure for details.
 288 */
 289int btrfs_read_extent_buffer(struct extent_buffer *eb,
 290			     struct btrfs_tree_parent_check *check)
 291{
 292	struct btrfs_fs_info *fs_info = eb->fs_info;
 293	int failed = 0;
 294	int ret;
 295	int num_copies = 0;
 296	int mirror_num = 0;
 297	int failed_mirror = 0;
 298
 299	ASSERT(check);
 300
 301	while (1) {
 302		clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 303		ret = read_extent_buffer_pages(eb, WAIT_COMPLETE, mirror_num, check);
 304		if (!ret)
 305			break;
 306
 307		num_copies = btrfs_num_copies(fs_info,
 308					      eb->start, eb->len);
 309		if (num_copies == 1)
 310			break;
 311
 312		if (!failed_mirror) {
 313			failed = 1;
 314			failed_mirror = eb->read_mirror;
 315		}
 316
 317		mirror_num++;
 318		if (mirror_num == failed_mirror)
 319			mirror_num++;
 320
 321		if (mirror_num > num_copies)
 322			break;
 323	}
 324
 325	if (failed && !ret && failed_mirror)
 326		btrfs_repair_eb_io_failure(eb, failed_mirror);
 327
 328	return ret;
 329}
 330
 331static int csum_one_extent_buffer(struct extent_buffer *eb)
 
 
 
 332{
 
 333	struct btrfs_fs_info *fs_info = eb->fs_info;
 
 
 334	u8 result[BTRFS_CSUM_SIZE];
 335	int ret;
 336
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 337	ASSERT(memcmp_extent_buffer(eb, fs_info->fs_devices->metadata_uuid,
 338				    offsetof(struct btrfs_header, fsid),
 339				    BTRFS_FSID_SIZE) == 0);
 340	csum_tree_block(eb, result);
 341
 342	if (btrfs_header_level(eb))
 343		ret = btrfs_check_node(eb);
 344	else
 345		ret = btrfs_check_leaf_full(eb);
 346
 347	if (ret < 0)
 348		goto error;
 349
 350	/*
 351	 * Also check the generation, the eb reached here must be newer than
 352	 * last committed. Or something seriously wrong happened.
 353	 */
 354	if (unlikely(btrfs_header_generation(eb) <= fs_info->last_trans_committed)) {
 
 355		ret = -EUCLEAN;
 356		btrfs_err(fs_info,
 357			"block=%llu bad generation, have %llu expect > %llu",
 358			  eb->start, btrfs_header_generation(eb),
 359			  fs_info->last_trans_committed);
 360		goto error;
 361	}
 362	write_extent_buffer(eb, result, 0, fs_info->csum_size);
 363
 364	return 0;
 365
 366error:
 367	btrfs_print_tree(eb, 0);
 368	btrfs_err(fs_info, "block=%llu write time tree block corruption detected",
 369		  eb->start);
 370	/*
 371	 * Be noisy if this is an extent buffer from a log tree. We don't abort
 372	 * a transaction in case there's a bad log tree extent buffer, we just
 373	 * fallback to a transaction commit. Still we want to know when there is
 374	 * a bad log tree extent buffer, as that may signal a bug somewhere.
 375	 */
 376	WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG) ||
 377		btrfs_header_owner(eb) == BTRFS_TREE_LOG_OBJECTID);
 378	return ret;
 379}
 380
 381/* Checksum all dirty extent buffers in one bio_vec */
 382static int csum_dirty_subpage_buffers(struct btrfs_fs_info *fs_info,
 383				      struct bio_vec *bvec)
 384{
 385	struct page *page = bvec->bv_page;
 386	u64 bvec_start = page_offset(page) + bvec->bv_offset;
 387	u64 cur;
 388	int ret = 0;
 389
 390	for (cur = bvec_start; cur < bvec_start + bvec->bv_len;
 391	     cur += fs_info->nodesize) {
 392		struct extent_buffer *eb;
 393		bool uptodate;
 394
 395		eb = find_extent_buffer(fs_info, cur);
 396		uptodate = btrfs_subpage_test_uptodate(fs_info, page, cur,
 397						       fs_info->nodesize);
 398
 399		/* A dirty eb shouldn't disappear from buffer_radix */
 400		if (WARN_ON(!eb))
 401			return -EUCLEAN;
 402
 403		if (WARN_ON(cur != btrfs_header_bytenr(eb))) {
 404			free_extent_buffer(eb);
 405			return -EUCLEAN;
 406		}
 407		if (WARN_ON(!uptodate)) {
 408			free_extent_buffer(eb);
 409			return -EUCLEAN;
 410		}
 411
 412		ret = csum_one_extent_buffer(eb);
 413		free_extent_buffer(eb);
 414		if (ret < 0)
 415			return ret;
 416	}
 417	return ret;
 418}
 419
 420/*
 421 * Checksum a dirty tree block before IO.  This has extra checks to make sure
 422 * we only fill in the checksum field in the first page of a multi-page block.
 423 * For subpage extent buffers we need bvec to also read the offset in the page.
 424 */
 425static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct bio_vec *bvec)
 426{
 427	struct page *page = bvec->bv_page;
 428	u64 start = page_offset(page);
 429	u64 found_start;
 430	struct extent_buffer *eb;
 431
 432	if (fs_info->nodesize < PAGE_SIZE)
 433		return csum_dirty_subpage_buffers(fs_info, bvec);
 434
 435	eb = (struct extent_buffer *)page->private;
 436	if (page != eb->pages[0])
 437		return 0;
 438
 439	found_start = btrfs_header_bytenr(eb);
 440
 441	if (test_bit(EXTENT_BUFFER_NO_CHECK, &eb->bflags)) {
 442		WARN_ON(found_start != 0);
 443		return 0;
 444	}
 445
 446	/*
 447	 * Please do not consolidate these warnings into a single if.
 448	 * It is useful to know what went wrong.
 449	 */
 450	if (WARN_ON(found_start != start))
 451		return -EUCLEAN;
 452	if (WARN_ON(!PageUptodate(page)))
 453		return -EUCLEAN;
 454
 455	return csum_one_extent_buffer(eb);
 456}
 457
 458static int check_tree_block_fsid(struct extent_buffer *eb)
 459{
 460	struct btrfs_fs_info *fs_info = eb->fs_info;
 461	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
 462	u8 fsid[BTRFS_FSID_SIZE];
 463	u8 *metadata_uuid;
 464
 465	read_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid),
 466			   BTRFS_FSID_SIZE);
 
 467	/*
 468	 * Checking the incompat flag is only valid for the current fs. For
 469	 * seed devices it's forbidden to have their uuid changed so reading
 470	 * ->fsid in this case is fine
 
 471	 */
 472	if (btrfs_fs_incompat(fs_info, METADATA_UUID))
 473		metadata_uuid = fs_devices->metadata_uuid;
 474	else
 475		metadata_uuid = fs_devices->fsid;
 476
 477	if (!memcmp(fsid, metadata_uuid, BTRFS_FSID_SIZE))
 478		return 0;
 479
 480	list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list)
 481		if (!memcmp(fsid, seed_devs->fsid, BTRFS_FSID_SIZE))
 482			return 0;
 483
 484	return 1;
 485}
 486
 487/* Do basic extent buffer checks at read time */
 488static int validate_extent_buffer(struct extent_buffer *eb,
 489				  struct btrfs_tree_parent_check *check)
 490{
 491	struct btrfs_fs_info *fs_info = eb->fs_info;
 492	u64 found_start;
 493	const u32 csum_size = fs_info->csum_size;
 494	u8 found_level;
 495	u8 result[BTRFS_CSUM_SIZE];
 496	const u8 *header_csum;
 497	int ret = 0;
 498
 499	ASSERT(check);
 500
 501	found_start = btrfs_header_bytenr(eb);
 502	if (found_start != eb->start) {
 503		btrfs_err_rl(fs_info,
 504			"bad tree block start, mirror %u want %llu have %llu",
 505			     eb->read_mirror, eb->start, found_start);
 506		ret = -EIO;
 507		goto out;
 508	}
 509	if (check_tree_block_fsid(eb)) {
 510		btrfs_err_rl(fs_info, "bad fsid on logical %llu mirror %u",
 511			     eb->start, eb->read_mirror);
 512		ret = -EIO;
 513		goto out;
 514	}
 515	found_level = btrfs_header_level(eb);
 516	if (found_level >= BTRFS_MAX_LEVEL) {
 517		btrfs_err(fs_info,
 518			"bad tree block level, mirror %u level %d on logical %llu",
 519			eb->read_mirror, btrfs_header_level(eb), eb->start);
 520		ret = -EIO;
 521		goto out;
 522	}
 523
 524	csum_tree_block(eb, result);
 525	header_csum = page_address(eb->pages[0]) +
 526		get_eb_offset_in_page(eb, offsetof(struct btrfs_header, csum));
 527
 528	if (memcmp(result, header_csum, csum_size) != 0) {
 529		btrfs_warn_rl(fs_info,
 530"checksum verify failed on logical %llu mirror %u wanted " CSUM_FMT " found " CSUM_FMT " level %d",
 531			      eb->start, eb->read_mirror,
 532			      CSUM_FMT_VALUE(csum_size, header_csum),
 533			      CSUM_FMT_VALUE(csum_size, result),
 534			      btrfs_header_level(eb));
 535		ret = -EUCLEAN;
 536		goto out;
 537	}
 538
 539	if (found_level != check->level) {
 540		btrfs_err(fs_info,
 541		"level verify failed on logical %llu mirror %u wanted %u found %u",
 542			  eb->start, eb->read_mirror, check->level, found_level);
 543		ret = -EIO;
 544		goto out;
 545	}
 546	if (unlikely(check->transid &&
 547		     btrfs_header_generation(eb) != check->transid)) {
 548		btrfs_err_rl(eb->fs_info,
 549"parent transid verify failed on logical %llu mirror %u wanted %llu found %llu",
 550				eb->start, eb->read_mirror, check->transid,
 551				btrfs_header_generation(eb));
 552		ret = -EIO;
 553		goto out;
 554	}
 555	if (check->has_first_key) {
 556		struct btrfs_key *expect_key = &check->first_key;
 557		struct btrfs_key found_key;
 558
 559		if (found_level)
 560			btrfs_node_key_to_cpu(eb, &found_key, 0);
 561		else
 562			btrfs_item_key_to_cpu(eb, &found_key, 0);
 563		if (unlikely(btrfs_comp_cpu_keys(expect_key, &found_key))) {
 564			btrfs_err(fs_info,
 565"tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
 566				  eb->start, check->transid,
 567				  expect_key->objectid,
 568				  expect_key->type, expect_key->offset,
 569				  found_key.objectid, found_key.type,
 570				  found_key.offset);
 571			ret = -EUCLEAN;
 572			goto out;
 573		}
 574	}
 575	if (check->owner_root) {
 576		ret = btrfs_check_eb_owner(eb, check->owner_root);
 577		if (ret < 0)
 578			goto out;
 579	}
 580
 581	/*
 582	 * If this is a leaf block and it is corrupt, set the corrupt bit so
 583	 * that we don't try and read the other copies of this block, just
 584	 * return -EIO.
 585	 */
 586	if (found_level == 0 && btrfs_check_leaf_full(eb)) {
 587		set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 588		ret = -EIO;
 589	}
 590
 591	if (found_level > 0 && btrfs_check_node(eb))
 592		ret = -EIO;
 593
 594	if (!ret)
 595		set_extent_buffer_uptodate(eb);
 596	else
 597		btrfs_err(fs_info,
 598		"read time tree block corruption detected on logical %llu mirror %u",
 599			  eb->start, eb->read_mirror);
 600out:
 601	return ret;
 602}
 603
 604static int validate_subpage_buffer(struct page *page, u64 start, u64 end,
 605				   int mirror, struct btrfs_tree_parent_check *check)
 606{
 607	struct btrfs_fs_info *fs_info = btrfs_sb(page->mapping->host->i_sb);
 608	struct extent_buffer *eb;
 609	bool reads_done;
 610	int ret = 0;
 611
 612	ASSERT(check);
 613
 614	/*
 615	 * We don't allow bio merge for subpage metadata read, so we should
 616	 * only get one eb for each endio hook.
 617	 */
 618	ASSERT(end == start + fs_info->nodesize - 1);
 619	ASSERT(PagePrivate(page));
 620
 621	eb = find_extent_buffer(fs_info, start);
 622	/*
 623	 * When we are reading one tree block, eb must have been inserted into
 624	 * the radix tree. If not, something is wrong.
 625	 */
 626	ASSERT(eb);
 627
 628	reads_done = atomic_dec_and_test(&eb->io_pages);
 629	/* Subpage read must finish in page read */
 630	ASSERT(reads_done);
 631
 632	eb->read_mirror = mirror;
 633	if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
 634		ret = -EIO;
 635		goto err;
 636	}
 637	ret = validate_extent_buffer(eb, check);
 638	if (ret < 0)
 639		goto err;
 640
 641	set_extent_buffer_uptodate(eb);
 642
 643	free_extent_buffer(eb);
 644	return ret;
 645err:
 646	/*
 647	 * end_bio_extent_readpage decrements io_pages in case of error,
 648	 * make sure it has something to decrement.
 649	 */
 650	atomic_inc(&eb->io_pages);
 651	clear_extent_buffer_uptodate(eb);
 652	free_extent_buffer(eb);
 653	return ret;
 654}
 655
 656int btrfs_validate_metadata_buffer(struct btrfs_bio *bbio,
 657				   struct page *page, u64 start, u64 end,
 658				   int mirror)
 659{
 660	struct extent_buffer *eb;
 661	int ret = 0;
 662	int reads_done;
 663
 664	ASSERT(page->private);
 665
 666	if (btrfs_sb(page->mapping->host->i_sb)->nodesize < PAGE_SIZE)
 667		return validate_subpage_buffer(page, start, end, mirror,
 668					       &bbio->parent_check);
 669
 670	eb = (struct extent_buffer *)page->private;
 671
 672	/*
 673	 * The pending IO might have been the only thing that kept this buffer
 674	 * in memory.  Make sure we have a ref for all this other checks
 675	 */
 676	atomic_inc(&eb->refs);
 677
 678	reads_done = atomic_dec_and_test(&eb->io_pages);
 679	if (!reads_done)
 680		goto err;
 681
 682	eb->read_mirror = mirror;
 683	if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
 684		ret = -EIO;
 685		goto err;
 686	}
 687	ret = validate_extent_buffer(eb, &bbio->parent_check);
 688err:
 689	if (ret) {
 690		/*
 691		 * our io error hook is going to dec the io pages
 692		 * again, we have to make sure it has something
 693		 * to decrement
 694		 */
 695		atomic_inc(&eb->io_pages);
 696		clear_extent_buffer_uptodate(eb);
 697	}
 698	free_extent_buffer(eb);
 699
 700	return ret;
 701}
 702
 703static void run_one_async_start(struct btrfs_work *work)
 704{
 705	struct async_submit_bio *async;
 706	blk_status_t ret;
 707
 708	async = container_of(work, struct  async_submit_bio, work);
 709	switch (async->submit_cmd) {
 710	case WQ_SUBMIT_METADATA:
 711		ret = btree_submit_bio_start(async->bio);
 712		break;
 713	case WQ_SUBMIT_DATA:
 714		ret = btrfs_submit_bio_start(async->inode, async->bio);
 715		break;
 716	case WQ_SUBMIT_DATA_DIO:
 717		ret = btrfs_submit_bio_start_direct_io(async->inode,
 718				async->bio, async->dio_file_offset);
 719		break;
 720	}
 721	if (ret)
 722		async->status = ret;
 723}
 724
 725/*
 726 * In order to insert checksums into the metadata in large chunks, we wait
 727 * until bio submission time.   All the pages in the bio are checksummed and
 728 * sums are attached onto the ordered extent record.
 729 *
 730 * At IO completion time the csums attached on the ordered extent record are
 731 * inserted into the tree.
 732 */
 733static void run_one_async_done(struct btrfs_work *work)
 734{
 735	struct async_submit_bio *async =
 736		container_of(work, struct  async_submit_bio, work);
 737	struct btrfs_inode *inode = async->inode;
 738	struct btrfs_bio *bbio = btrfs_bio(async->bio);
 739
 740	/* If an error occurred we just want to clean up the bio and move on */
 741	if (async->status) {
 742		btrfs_bio_end_io(bbio, async->status);
 743		return;
 744	}
 745
 746	/*
 747	 * All of the bios that pass through here are from async helpers.
 748	 * Use REQ_CGROUP_PUNT to issue them from the owning cgroup's context.
 749	 * This changes nothing when cgroups aren't in use.
 750	 */
 751	async->bio->bi_opf |= REQ_CGROUP_PUNT;
 752	btrfs_submit_bio(inode->root->fs_info, async->bio, async->mirror_num);
 753}
 754
 755static void run_one_async_free(struct btrfs_work *work)
 756{
 757	struct async_submit_bio *async;
 758
 759	async = container_of(work, struct  async_submit_bio, work);
 760	kfree(async);
 761}
 762
 763/*
 764 * Submit bio to an async queue.
 765 *
 766 * Retrun:
 767 * - true if the work has been succesfuly submitted
 768 * - false in case of error
 769 */
 770bool btrfs_wq_submit_bio(struct btrfs_inode *inode, struct bio *bio, int mirror_num,
 771			 u64 dio_file_offset, enum btrfs_wq_submit_cmd cmd)
 772{
 773	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 774	struct async_submit_bio *async;
 775
 776	async = kmalloc(sizeof(*async), GFP_NOFS);
 777	if (!async)
 778		return false;
 779
 780	async->inode = inode;
 781	async->bio = bio;
 782	async->mirror_num = mirror_num;
 783	async->submit_cmd = cmd;
 784
 785	btrfs_init_work(&async->work, run_one_async_start, run_one_async_done,
 786			run_one_async_free);
 787
 788	async->dio_file_offset = dio_file_offset;
 789
 790	async->status = 0;
 791
 792	if (op_is_sync(bio->bi_opf))
 793		btrfs_queue_work(fs_info->hipri_workers, &async->work);
 794	else
 795		btrfs_queue_work(fs_info->workers, &async->work);
 796	return true;
 797}
 798
 799static blk_status_t btree_csum_one_bio(struct bio *bio)
 800{
 801	struct bio_vec *bvec;
 802	struct btrfs_root *root;
 803	int ret = 0;
 804	struct bvec_iter_all iter_all;
 805
 806	ASSERT(!bio_flagged(bio, BIO_CLONED));
 807	bio_for_each_segment_all(bvec, bio, iter_all) {
 808		root = BTRFS_I(bvec->bv_page->mapping->host)->root;
 809		ret = csum_dirty_buffer(root->fs_info, bvec);
 810		if (ret)
 811			break;
 812	}
 813
 814	return errno_to_blk_status(ret);
 815}
 816
 817blk_status_t btree_submit_bio_start(struct bio *bio)
 818{
 819	/*
 820	 * when we're called for a write, we're already in the async
 821	 * submission context.  Just jump into btrfs_submit_bio.
 822	 */
 823	return btree_csum_one_bio(bio);
 824}
 825
 826static bool should_async_write(struct btrfs_fs_info *fs_info,
 827			     struct btrfs_inode *bi)
 828{
 829	if (btrfs_is_zoned(fs_info))
 830		return false;
 831	if (atomic_read(&bi->sync_writers))
 832		return false;
 833	if (test_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags))
 834		return false;
 835	return true;
 836}
 837
 838void btrfs_submit_metadata_bio(struct btrfs_inode *inode, struct bio *bio, int mirror_num)
 839{
 840	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 841	struct btrfs_bio *bbio = btrfs_bio(bio);
 842	blk_status_t ret;
 843
 844	bio->bi_opf |= REQ_META;
 845	bbio->is_metadata = 1;
 846
 847	if (btrfs_op(bio) != BTRFS_MAP_WRITE) {
 848		btrfs_submit_bio(fs_info, bio, mirror_num);
 849		return;
 850	}
 851
 852	/*
 853	 * Kthread helpers are used to submit writes so that checksumming can
 854	 * happen in parallel across all CPUs.
 855	 */
 856	if (should_async_write(fs_info, inode) &&
 857	    btrfs_wq_submit_bio(inode, bio, mirror_num, 0, WQ_SUBMIT_METADATA))
 858		return;
 859
 860	ret = btree_csum_one_bio(bio);
 861	if (ret) {
 862		btrfs_bio_end_io(bbio, ret);
 863		return;
 864	}
 865
 866	btrfs_submit_bio(fs_info, bio, mirror_num);
 867}
 868
 869#ifdef CONFIG_MIGRATION
 870static int btree_migrate_folio(struct address_space *mapping,
 871		struct folio *dst, struct folio *src, enum migrate_mode mode)
 872{
 873	/*
 874	 * we can't safely write a btree page from here,
 875	 * we haven't done the locking hook
 876	 */
 877	if (folio_test_dirty(src))
 878		return -EAGAIN;
 879	/*
 880	 * Buffers may be managed in a filesystem specific way.
 881	 * We must have no buffers or drop them.
 882	 */
 883	if (folio_get_private(src) &&
 884	    !filemap_release_folio(src, GFP_KERNEL))
 885		return -EAGAIN;
 886	return migrate_folio(mapping, dst, src, mode);
 887}
 888#else
 889#define btree_migrate_folio NULL
 890#endif
 891
 892static int btree_writepages(struct address_space *mapping,
 893			    struct writeback_control *wbc)
 894{
 895	struct btrfs_fs_info *fs_info;
 896	int ret;
 897
 898	if (wbc->sync_mode == WB_SYNC_NONE) {
 899
 900		if (wbc->for_kupdate)
 901			return 0;
 902
 903		fs_info = BTRFS_I(mapping->host)->root->fs_info;
 904		/* this is a bit racy, but that's ok */
 905		ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
 906					     BTRFS_DIRTY_METADATA_THRESH,
 907					     fs_info->dirty_metadata_batch);
 908		if (ret < 0)
 909			return 0;
 910	}
 911	return btree_write_cache_pages(mapping, wbc);
 912}
 913
 914static bool btree_release_folio(struct folio *folio, gfp_t gfp_flags)
 915{
 916	if (folio_test_writeback(folio) || folio_test_dirty(folio))
 917		return false;
 918
 919	return try_release_extent_buffer(&folio->page);
 920}
 921
 922static void btree_invalidate_folio(struct folio *folio, size_t offset,
 923				 size_t length)
 924{
 925	struct extent_io_tree *tree;
 926	tree = &BTRFS_I(folio->mapping->host)->io_tree;
 927	extent_invalidate_folio(tree, folio, offset);
 928	btree_release_folio(folio, GFP_NOFS);
 929	if (folio_get_private(folio)) {
 930		btrfs_warn(BTRFS_I(folio->mapping->host)->root->fs_info,
 931			   "folio private not zero on folio %llu",
 932			   (unsigned long long)folio_pos(folio));
 933		folio_detach_private(folio);
 934	}
 935}
 936
 937#ifdef DEBUG
 938static bool btree_dirty_folio(struct address_space *mapping,
 939		struct folio *folio)
 940{
 941	struct btrfs_fs_info *fs_info = btrfs_sb(mapping->host->i_sb);
 
 942	struct btrfs_subpage *subpage;
 943	struct extent_buffer *eb;
 944	int cur_bit = 0;
 945	u64 page_start = folio_pos(folio);
 946
 947	if (fs_info->sectorsize == PAGE_SIZE) {
 948		eb = folio_get_private(folio);
 949		BUG_ON(!eb);
 950		BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
 951		BUG_ON(!atomic_read(&eb->refs));
 952		btrfs_assert_tree_write_locked(eb);
 953		return filemap_dirty_folio(mapping, folio);
 954	}
 
 
 955	subpage = folio_get_private(folio);
 956
 957	ASSERT(subpage->dirty_bitmap);
 958	while (cur_bit < BTRFS_SUBPAGE_BITMAP_SIZE) {
 
 959		unsigned long flags;
 960		u64 cur;
 961		u16 tmp = (1 << cur_bit);
 962
 963		spin_lock_irqsave(&subpage->lock, flags);
 964		if (!(tmp & subpage->dirty_bitmap)) {
 965			spin_unlock_irqrestore(&subpage->lock, flags);
 966			cur_bit++;
 967			continue;
 968		}
 969		spin_unlock_irqrestore(&subpage->lock, flags);
 970		cur = page_start + cur_bit * fs_info->sectorsize;
 971
 972		eb = find_extent_buffer(fs_info, cur);
 973		ASSERT(eb);
 974		ASSERT(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
 975		ASSERT(atomic_read(&eb->refs));
 976		btrfs_assert_tree_write_locked(eb);
 977		free_extent_buffer(eb);
 978
 979		cur_bit += (fs_info->nodesize >> fs_info->sectorsize_bits);
 980	}
 981	return filemap_dirty_folio(mapping, folio);
 982}
 983#else
 984#define btree_dirty_folio filemap_dirty_folio
 985#endif
 986
 987static const struct address_space_operations btree_aops = {
 988	.writepages	= btree_writepages,
 989	.release_folio	= btree_release_folio,
 990	.invalidate_folio = btree_invalidate_folio,
 991	.migrate_folio	= btree_migrate_folio,
 992	.dirty_folio	= btree_dirty_folio,
 993};
 994
 995struct extent_buffer *btrfs_find_create_tree_block(
 996						struct btrfs_fs_info *fs_info,
 997						u64 bytenr, u64 owner_root,
 998						int level)
 999{
1000	if (btrfs_is_testing(fs_info))
1001		return alloc_test_extent_buffer(fs_info, bytenr);
1002	return alloc_extent_buffer(fs_info, bytenr, owner_root, level);
1003}
1004
1005/*
1006 * Read tree block at logical address @bytenr and do variant basic but critical
1007 * verification.
1008 *
1009 * @check:		expected tree parentness check, see comments of the
1010 *			structure for details.
1011 */
1012struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
1013				      struct btrfs_tree_parent_check *check)
1014{
1015	struct extent_buffer *buf = NULL;
1016	int ret;
1017
1018	ASSERT(check);
1019
1020	buf = btrfs_find_create_tree_block(fs_info, bytenr, check->owner_root,
1021					   check->level);
1022	if (IS_ERR(buf))
1023		return buf;
1024
1025	ret = btrfs_read_extent_buffer(buf, check);
1026	if (ret) {
1027		free_extent_buffer_stale(buf);
1028		return ERR_PTR(ret);
1029	}
1030	if (btrfs_check_eb_owner(buf, check->owner_root)) {
1031		free_extent_buffer_stale(buf);
1032		return ERR_PTR(-EUCLEAN);
1033	}
1034	return buf;
1035
1036}
1037
1038void btrfs_clean_tree_block(struct extent_buffer *buf)
1039{
1040	struct btrfs_fs_info *fs_info = buf->fs_info;
1041	if (btrfs_header_generation(buf) ==
1042	    fs_info->running_transaction->transid) {
1043		btrfs_assert_tree_write_locked(buf);
1044
1045		if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
1046			percpu_counter_add_batch(&fs_info->dirty_metadata_bytes,
1047						 -buf->len,
1048						 fs_info->dirty_metadata_batch);
1049			clear_extent_buffer_dirty(buf);
1050		}
1051	}
1052}
1053
1054static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
1055			 u64 objectid)
1056{
1057	bool dummy = test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state);
1058
1059	memset(&root->root_key, 0, sizeof(root->root_key));
1060	memset(&root->root_item, 0, sizeof(root->root_item));
1061	memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
1062	root->fs_info = fs_info;
1063	root->root_key.objectid = objectid;
1064	root->node = NULL;
1065	root->commit_root = NULL;
1066	root->state = 0;
1067	RB_CLEAR_NODE(&root->rb_node);
1068
1069	root->last_trans = 0;
1070	root->free_objectid = 0;
1071	root->nr_delalloc_inodes = 0;
1072	root->nr_ordered_extents = 0;
1073	root->inode_tree = RB_ROOT;
1074	INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
 
1075
1076	btrfs_init_root_block_rsv(root);
1077
1078	INIT_LIST_HEAD(&root->dirty_list);
1079	INIT_LIST_HEAD(&root->root_list);
1080	INIT_LIST_HEAD(&root->delalloc_inodes);
1081	INIT_LIST_HEAD(&root->delalloc_root);
1082	INIT_LIST_HEAD(&root->ordered_extents);
1083	INIT_LIST_HEAD(&root->ordered_root);
1084	INIT_LIST_HEAD(&root->reloc_dirty_list);
1085	INIT_LIST_HEAD(&root->logged_list[0]);
1086	INIT_LIST_HEAD(&root->logged_list[1]);
1087	spin_lock_init(&root->inode_lock);
1088	spin_lock_init(&root->delalloc_lock);
1089	spin_lock_init(&root->ordered_extent_lock);
1090	spin_lock_init(&root->accounting_lock);
1091	spin_lock_init(&root->log_extents_lock[0]);
1092	spin_lock_init(&root->log_extents_lock[1]);
1093	spin_lock_init(&root->qgroup_meta_rsv_lock);
1094	mutex_init(&root->objectid_mutex);
1095	mutex_init(&root->log_mutex);
1096	mutex_init(&root->ordered_extent_mutex);
1097	mutex_init(&root->delalloc_mutex);
1098	init_waitqueue_head(&root->qgroup_flush_wait);
1099	init_waitqueue_head(&root->log_writer_wait);
1100	init_waitqueue_head(&root->log_commit_wait[0]);
1101	init_waitqueue_head(&root->log_commit_wait[1]);
1102	INIT_LIST_HEAD(&root->log_ctxs[0]);
1103	INIT_LIST_HEAD(&root->log_ctxs[1]);
1104	atomic_set(&root->log_commit[0], 0);
1105	atomic_set(&root->log_commit[1], 0);
1106	atomic_set(&root->log_writers, 0);
1107	atomic_set(&root->log_batch, 0);
1108	refcount_set(&root->refs, 1);
1109	atomic_set(&root->snapshot_force_cow, 0);
1110	atomic_set(&root->nr_swapfiles, 0);
1111	root->log_transid = 0;
1112	root->log_transid_committed = -1;
1113	root->last_log_commit = 0;
1114	root->anon_dev = 0;
1115	if (!dummy) {
1116		extent_io_tree_init(fs_info, &root->dirty_log_pages,
1117				    IO_TREE_ROOT_DIRTY_LOG_PAGES);
1118		extent_io_tree_init(fs_info, &root->log_csum_range,
1119				    IO_TREE_LOG_CSUM_RANGE);
1120	}
1121
1122	spin_lock_init(&root->root_item_lock);
1123	btrfs_qgroup_init_swapped_blocks(&root->swapped_blocks);
1124#ifdef CONFIG_BTRFS_DEBUG
1125	INIT_LIST_HEAD(&root->leak_list);
1126	spin_lock(&fs_info->fs_roots_radix_lock);
1127	list_add_tail(&root->leak_list, &fs_info->allocated_roots);
1128	spin_unlock(&fs_info->fs_roots_radix_lock);
1129#endif
1130}
1131
1132static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info,
1133					   u64 objectid, gfp_t flags)
1134{
1135	struct btrfs_root *root = kzalloc(sizeof(*root), flags);
1136	if (root)
1137		__setup_root(root, fs_info, objectid);
1138	return root;
1139}
1140
1141#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
1142/* Should only be used by the testing infrastructure */
1143struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info)
1144{
1145	struct btrfs_root *root;
1146
1147	if (!fs_info)
1148		return ERR_PTR(-EINVAL);
1149
1150	root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID, GFP_KERNEL);
1151	if (!root)
1152		return ERR_PTR(-ENOMEM);
1153
1154	/* We don't use the stripesize in selftest, set it as sectorsize */
1155	root->alloc_bytenr = 0;
1156
1157	return root;
1158}
1159#endif
1160
1161static int global_root_cmp(struct rb_node *a_node, const struct rb_node *b_node)
1162{
1163	const struct btrfs_root *a = rb_entry(a_node, struct btrfs_root, rb_node);
1164	const struct btrfs_root *b = rb_entry(b_node, struct btrfs_root, rb_node);
1165
1166	return btrfs_comp_cpu_keys(&a->root_key, &b->root_key);
1167}
1168
1169static int global_root_key_cmp(const void *k, const struct rb_node *node)
1170{
1171	const struct btrfs_key *key = k;
1172	const struct btrfs_root *root = rb_entry(node, struct btrfs_root, rb_node);
1173
1174	return btrfs_comp_cpu_keys(key, &root->root_key);
1175}
1176
1177int btrfs_global_root_insert(struct btrfs_root *root)
1178{
1179	struct btrfs_fs_info *fs_info = root->fs_info;
1180	struct rb_node *tmp;
 
1181
1182	write_lock(&fs_info->global_root_lock);
1183	tmp = rb_find_add(&root->rb_node, &fs_info->global_root_tree, global_root_cmp);
1184	write_unlock(&fs_info->global_root_lock);
1185	ASSERT(!tmp);
1186
1187	return tmp ? -EEXIST : 0;
 
 
 
 
 
1188}
1189
1190void btrfs_global_root_delete(struct btrfs_root *root)
1191{
1192	struct btrfs_fs_info *fs_info = root->fs_info;
1193
1194	write_lock(&fs_info->global_root_lock);
1195	rb_erase(&root->rb_node, &fs_info->global_root_tree);
1196	write_unlock(&fs_info->global_root_lock);
1197}
1198
1199struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info,
1200				     struct btrfs_key *key)
1201{
1202	struct rb_node *node;
1203	struct btrfs_root *root = NULL;
1204
1205	read_lock(&fs_info->global_root_lock);
1206	node = rb_find(key, &fs_info->global_root_tree, global_root_key_cmp);
1207	if (node)
1208		root = container_of(node, struct btrfs_root, rb_node);
1209	read_unlock(&fs_info->global_root_lock);
1210
1211	return root;
1212}
1213
1214static u64 btrfs_global_root_id(struct btrfs_fs_info *fs_info, u64 bytenr)
1215{
1216	struct btrfs_block_group *block_group;
1217	u64 ret;
1218
1219	if (!btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
1220		return 0;
1221
1222	if (bytenr)
1223		block_group = btrfs_lookup_block_group(fs_info, bytenr);
1224	else
1225		block_group = btrfs_lookup_first_block_group(fs_info, bytenr);
1226	ASSERT(block_group);
1227	if (!block_group)
1228		return 0;
1229	ret = block_group->global_root_id;
1230	btrfs_put_block_group(block_group);
1231
1232	return ret;
1233}
1234
1235struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr)
1236{
1237	struct btrfs_key key = {
1238		.objectid = BTRFS_CSUM_TREE_OBJECTID,
1239		.type = BTRFS_ROOT_ITEM_KEY,
1240		.offset = btrfs_global_root_id(fs_info, bytenr),
1241	};
1242
1243	return btrfs_global_root(fs_info, &key);
1244}
1245
1246struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr)
1247{
1248	struct btrfs_key key = {
1249		.objectid = BTRFS_EXTENT_TREE_OBJECTID,
1250		.type = BTRFS_ROOT_ITEM_KEY,
1251		.offset = btrfs_global_root_id(fs_info, bytenr),
1252	};
1253
1254	return btrfs_global_root(fs_info, &key);
1255}
1256
1257struct btrfs_root *btrfs_block_group_root(struct btrfs_fs_info *fs_info)
1258{
1259	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE))
1260		return fs_info->block_group_root;
1261	return btrfs_extent_root(fs_info, 0);
1262}
1263
1264struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
1265				     u64 objectid)
1266{
1267	struct btrfs_fs_info *fs_info = trans->fs_info;
1268	struct extent_buffer *leaf;
1269	struct btrfs_root *tree_root = fs_info->tree_root;
1270	struct btrfs_root *root;
1271	struct btrfs_key key;
1272	unsigned int nofs_flag;
1273	int ret = 0;
1274
1275	/*
1276	 * We're holding a transaction handle, so use a NOFS memory allocation
1277	 * context to avoid deadlock if reclaim happens.
1278	 */
1279	nofs_flag = memalloc_nofs_save();
1280	root = btrfs_alloc_root(fs_info, objectid, GFP_KERNEL);
1281	memalloc_nofs_restore(nofs_flag);
1282	if (!root)
1283		return ERR_PTR(-ENOMEM);
1284
1285	root->root_key.objectid = objectid;
1286	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1287	root->root_key.offset = 0;
1288
1289	leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0,
1290				      BTRFS_NESTING_NORMAL);
1291	if (IS_ERR(leaf)) {
1292		ret = PTR_ERR(leaf);
1293		leaf = NULL;
1294		goto fail;
1295	}
1296
1297	root->node = leaf;
1298	btrfs_mark_buffer_dirty(leaf);
1299
1300	root->commit_root = btrfs_root_node(root);
1301	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
1302
1303	btrfs_set_root_flags(&root->root_item, 0);
1304	btrfs_set_root_limit(&root->root_item, 0);
1305	btrfs_set_root_bytenr(&root->root_item, leaf->start);
1306	btrfs_set_root_generation(&root->root_item, trans->transid);
1307	btrfs_set_root_level(&root->root_item, 0);
1308	btrfs_set_root_refs(&root->root_item, 1);
1309	btrfs_set_root_used(&root->root_item, leaf->len);
1310	btrfs_set_root_last_snapshot(&root->root_item, 0);
1311	btrfs_set_root_dirid(&root->root_item, 0);
1312	if (is_fstree(objectid))
1313		generate_random_guid(root->root_item.uuid);
1314	else
1315		export_guid(root->root_item.uuid, &guid_null);
1316	btrfs_set_root_drop_level(&root->root_item, 0);
1317
1318	btrfs_tree_unlock(leaf);
1319
1320	key.objectid = objectid;
1321	key.type = BTRFS_ROOT_ITEM_KEY;
1322	key.offset = 0;
1323	ret = btrfs_insert_root(trans, tree_root, &key, &root->root_item);
1324	if (ret)
1325		goto fail;
1326
1327	return root;
1328
1329fail:
1330	btrfs_put_root(root);
1331
1332	return ERR_PTR(ret);
1333}
1334
1335static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
1336					 struct btrfs_fs_info *fs_info)
1337{
1338	struct btrfs_root *root;
1339
1340	root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID, GFP_NOFS);
1341	if (!root)
1342		return ERR_PTR(-ENOMEM);
1343
1344	root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1345	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1346	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
1347
1348	return root;
1349}
1350
1351int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
1352			      struct btrfs_root *root)
1353{
1354	struct extent_buffer *leaf;
1355
1356	/*
1357	 * DON'T set SHAREABLE bit for log trees.
1358	 *
1359	 * Log trees are not exposed to user space thus can't be snapshotted,
1360	 * and they go away before a real commit is actually done.
1361	 *
1362	 * They do store pointers to file data extents, and those reference
1363	 * counts still get updated (along with back refs to the log tree).
1364	 */
1365
1366	leaf = btrfs_alloc_tree_block(trans, root, 0, BTRFS_TREE_LOG_OBJECTID,
1367			NULL, 0, 0, 0, BTRFS_NESTING_NORMAL);
1368	if (IS_ERR(leaf))
1369		return PTR_ERR(leaf);
1370
1371	root->node = leaf;
1372
1373	btrfs_mark_buffer_dirty(root->node);
1374	btrfs_tree_unlock(root->node);
1375
1376	return 0;
1377}
1378
1379int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1380			     struct btrfs_fs_info *fs_info)
1381{
1382	struct btrfs_root *log_root;
1383
1384	log_root = alloc_log_tree(trans, fs_info);
1385	if (IS_ERR(log_root))
1386		return PTR_ERR(log_root);
1387
1388	if (!btrfs_is_zoned(fs_info)) {
1389		int ret = btrfs_alloc_log_tree_node(trans, log_root);
1390
1391		if (ret) {
1392			btrfs_put_root(log_root);
1393			return ret;
1394		}
1395	}
1396
1397	WARN_ON(fs_info->log_root_tree);
1398	fs_info->log_root_tree = log_root;
1399	return 0;
1400}
1401
1402int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1403		       struct btrfs_root *root)
1404{
1405	struct btrfs_fs_info *fs_info = root->fs_info;
1406	struct btrfs_root *log_root;
1407	struct btrfs_inode_item *inode_item;
1408	int ret;
1409
1410	log_root = alloc_log_tree(trans, fs_info);
1411	if (IS_ERR(log_root))
1412		return PTR_ERR(log_root);
1413
1414	ret = btrfs_alloc_log_tree_node(trans, log_root);
1415	if (ret) {
1416		btrfs_put_root(log_root);
1417		return ret;
1418	}
1419
1420	log_root->last_trans = trans->transid;
1421	log_root->root_key.offset = root->root_key.objectid;
1422
1423	inode_item = &log_root->root_item.inode;
1424	btrfs_set_stack_inode_generation(inode_item, 1);
1425	btrfs_set_stack_inode_size(inode_item, 3);
1426	btrfs_set_stack_inode_nlink(inode_item, 1);
1427	btrfs_set_stack_inode_nbytes(inode_item,
1428				     fs_info->nodesize);
1429	btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
1430
1431	btrfs_set_root_node(&log_root->root_item, log_root->node);
1432
1433	WARN_ON(root->log_root);
1434	root->log_root = log_root;
1435	root->log_transid = 0;
1436	root->log_transid_committed = -1;
1437	root->last_log_commit = 0;
1438	return 0;
1439}
1440
1441static struct btrfs_root *read_tree_root_path(struct btrfs_root *tree_root,
1442					      struct btrfs_path *path,
1443					      struct btrfs_key *key)
1444{
1445	struct btrfs_root *root;
1446	struct btrfs_tree_parent_check check = { 0 };
1447	struct btrfs_fs_info *fs_info = tree_root->fs_info;
1448	u64 generation;
1449	int ret;
1450	int level;
1451
1452	root = btrfs_alloc_root(fs_info, key->objectid, GFP_NOFS);
1453	if (!root)
1454		return ERR_PTR(-ENOMEM);
1455
1456	ret = btrfs_find_root(tree_root, key, path,
1457			      &root->root_item, &root->root_key);
1458	if (ret) {
1459		if (ret > 0)
1460			ret = -ENOENT;
1461		goto fail;
1462	}
1463
1464	generation = btrfs_root_generation(&root->root_item);
1465	level = btrfs_root_level(&root->root_item);
1466	check.level = level;
1467	check.transid = generation;
1468	check.owner_root = key->objectid;
1469	root->node = read_tree_block(fs_info, btrfs_root_bytenr(&root->root_item),
1470				     &check);
1471	if (IS_ERR(root->node)) {
1472		ret = PTR_ERR(root->node);
1473		root->node = NULL;
1474		goto fail;
1475	}
1476	if (!btrfs_buffer_uptodate(root->node, generation, 0)) {
1477		ret = -EIO;
1478		goto fail;
1479	}
1480
1481	/*
1482	 * For real fs, and not log/reloc trees, root owner must
1483	 * match its root node owner
1484	 */
1485	if (!test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state) &&
1486	    root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID &&
1487	    root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID &&
1488	    root->root_key.objectid != btrfs_header_owner(root->node)) {
1489		btrfs_crit(fs_info,
1490"root=%llu block=%llu, tree root owner mismatch, have %llu expect %llu",
1491			   root->root_key.objectid, root->node->start,
1492			   btrfs_header_owner(root->node),
1493			   root->root_key.objectid);
1494		ret = -EUCLEAN;
1495		goto fail;
1496	}
1497	root->commit_root = btrfs_root_node(root);
1498	return root;
1499fail:
1500	btrfs_put_root(root);
1501	return ERR_PTR(ret);
1502}
1503
1504struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
1505					struct btrfs_key *key)
1506{
1507	struct btrfs_root *root;
1508	struct btrfs_path *path;
1509
1510	path = btrfs_alloc_path();
1511	if (!path)
1512		return ERR_PTR(-ENOMEM);
1513	root = read_tree_root_path(tree_root, path, key);
1514	btrfs_free_path(path);
1515
1516	return root;
1517}
1518
1519/*
1520 * Initialize subvolume root in-memory structure
1521 *
1522 * @anon_dev:	anonymous device to attach to the root, if zero, allocate new
1523 */
1524static int btrfs_init_fs_root(struct btrfs_root *root, dev_t anon_dev)
1525{
1526	int ret;
1527	unsigned int nofs_flag;
1528
1529	/*
1530	 * We might be called under a transaction (e.g. indirect backref
1531	 * resolution) which could deadlock if it triggers memory reclaim
1532	 */
1533	nofs_flag = memalloc_nofs_save();
1534	ret = btrfs_drew_lock_init(&root->snapshot_lock);
1535	memalloc_nofs_restore(nofs_flag);
1536	if (ret)
1537		goto fail;
1538
1539	if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID &&
1540	    !btrfs_is_data_reloc_root(root)) {
 
1541		set_bit(BTRFS_ROOT_SHAREABLE, &root->state);
1542		btrfs_check_and_init_root_item(&root->root_item);
1543	}
1544
1545	/*
1546	 * Don't assign anonymous block device to roots that are not exposed to
1547	 * userspace, the id pool is limited to 1M
1548	 */
1549	if (is_fstree(root->root_key.objectid) &&
1550	    btrfs_root_refs(&root->root_item) > 0) {
1551		if (!anon_dev) {
1552			ret = get_anon_bdev(&root->anon_dev);
1553			if (ret)
1554				goto fail;
1555		} else {
1556			root->anon_dev = anon_dev;
1557		}
1558	}
1559
1560	mutex_lock(&root->objectid_mutex);
1561	ret = btrfs_init_root_free_objectid(root);
1562	if (ret) {
1563		mutex_unlock(&root->objectid_mutex);
1564		goto fail;
1565	}
1566
1567	ASSERT(root->free_objectid <= BTRFS_LAST_FREE_OBJECTID);
1568
1569	mutex_unlock(&root->objectid_mutex);
1570
1571	return 0;
1572fail:
1573	/* The caller is responsible to call btrfs_free_fs_root */
1574	return ret;
1575}
1576
1577static struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
1578					       u64 root_id)
1579{
1580	struct btrfs_root *root;
1581
1582	spin_lock(&fs_info->fs_roots_radix_lock);
1583	root = radix_tree_lookup(&fs_info->fs_roots_radix,
1584				 (unsigned long)root_id);
1585	if (root)
1586		root = btrfs_grab_root(root);
1587	spin_unlock(&fs_info->fs_roots_radix_lock);
1588	return root;
1589}
1590
1591static struct btrfs_root *btrfs_get_global_root(struct btrfs_fs_info *fs_info,
1592						u64 objectid)
1593{
1594	struct btrfs_key key = {
1595		.objectid = objectid,
1596		.type = BTRFS_ROOT_ITEM_KEY,
1597		.offset = 0,
1598	};
1599
1600	if (objectid == BTRFS_ROOT_TREE_OBJECTID)
 
1601		return btrfs_grab_root(fs_info->tree_root);
1602	if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
1603		return btrfs_grab_root(btrfs_global_root(fs_info, &key));
1604	if (objectid == BTRFS_CHUNK_TREE_OBJECTID)
1605		return btrfs_grab_root(fs_info->chunk_root);
1606	if (objectid == BTRFS_DEV_TREE_OBJECTID)
1607		return btrfs_grab_root(fs_info->dev_root);
1608	if (objectid == BTRFS_CSUM_TREE_OBJECTID)
 
 
 
 
 
 
 
 
1609		return btrfs_grab_root(btrfs_global_root(fs_info, &key));
1610	if (objectid == BTRFS_QUOTA_TREE_OBJECTID)
1611		return btrfs_grab_root(fs_info->quota_root) ?
1612			fs_info->quota_root : ERR_PTR(-ENOENT);
1613	if (objectid == BTRFS_UUID_TREE_OBJECTID)
1614		return btrfs_grab_root(fs_info->uuid_root) ?
1615			fs_info->uuid_root : ERR_PTR(-ENOENT);
1616	if (objectid == BTRFS_BLOCK_GROUP_TREE_OBJECTID)
1617		return btrfs_grab_root(fs_info->block_group_root) ?
1618			fs_info->block_group_root : ERR_PTR(-ENOENT);
1619	if (objectid == BTRFS_FREE_SPACE_TREE_OBJECTID) {
1620		struct btrfs_root *root = btrfs_global_root(fs_info, &key);
1621
1622		return btrfs_grab_root(root) ? root : ERR_PTR(-ENOENT);
1623	}
1624	return NULL;
1625}
1626
1627int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
1628			 struct btrfs_root *root)
1629{
1630	int ret;
1631
1632	ret = radix_tree_preload(GFP_NOFS);
1633	if (ret)
1634		return ret;
1635
1636	spin_lock(&fs_info->fs_roots_radix_lock);
1637	ret = radix_tree_insert(&fs_info->fs_roots_radix,
1638				(unsigned long)root->root_key.objectid,
1639				root);
1640	if (ret == 0) {
1641		btrfs_grab_root(root);
1642		set_bit(BTRFS_ROOT_IN_RADIX, &root->state);
1643	}
1644	spin_unlock(&fs_info->fs_roots_radix_lock);
1645	radix_tree_preload_end();
1646
1647	return ret;
1648}
1649
1650void btrfs_check_leaked_roots(struct btrfs_fs_info *fs_info)
1651{
1652#ifdef CONFIG_BTRFS_DEBUG
1653	struct btrfs_root *root;
1654
1655	while (!list_empty(&fs_info->allocated_roots)) {
1656		char buf[BTRFS_ROOT_NAME_BUF_LEN];
1657
1658		root = list_first_entry(&fs_info->allocated_roots,
1659					struct btrfs_root, leak_list);
1660		btrfs_err(fs_info, "leaked root %s refcount %d",
1661			  btrfs_root_name(&root->root_key, buf),
1662			  refcount_read(&root->refs));
1663		while (refcount_read(&root->refs) > 1)
1664			btrfs_put_root(root);
1665		btrfs_put_root(root);
1666	}
1667#endif
1668}
1669
1670static void free_global_roots(struct btrfs_fs_info *fs_info)
1671{
1672	struct btrfs_root *root;
1673	struct rb_node *node;
1674
1675	while ((node = rb_first_postorder(&fs_info->global_root_tree)) != NULL) {
1676		root = rb_entry(node, struct btrfs_root, rb_node);
1677		rb_erase(&root->rb_node, &fs_info->global_root_tree);
1678		btrfs_put_root(root);
1679	}
1680}
1681
1682void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
1683{
1684	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
1685	percpu_counter_destroy(&fs_info->delalloc_bytes);
1686	percpu_counter_destroy(&fs_info->ordered_bytes);
1687	percpu_counter_destroy(&fs_info->dev_replace.bio_counter);
1688	btrfs_free_csum_hash(fs_info);
1689	btrfs_free_stripe_hash_table(fs_info);
1690	btrfs_free_ref_cache(fs_info);
1691	kfree(fs_info->balance_ctl);
1692	kfree(fs_info->delayed_root);
1693	free_global_roots(fs_info);
1694	btrfs_put_root(fs_info->tree_root);
1695	btrfs_put_root(fs_info->chunk_root);
1696	btrfs_put_root(fs_info->dev_root);
1697	btrfs_put_root(fs_info->quota_root);
1698	btrfs_put_root(fs_info->uuid_root);
1699	btrfs_put_root(fs_info->fs_root);
1700	btrfs_put_root(fs_info->data_reloc_root);
1701	btrfs_put_root(fs_info->block_group_root);
 
1702	btrfs_check_leaked_roots(fs_info);
1703	btrfs_extent_buffer_leak_debug_check(fs_info);
1704	kfree(fs_info->super_copy);
1705	kfree(fs_info->super_for_commit);
1706	kfree(fs_info->subpage_info);
1707	kvfree(fs_info);
1708}
1709
1710
1711/*
1712 * Get an in-memory reference of a root structure.
1713 *
1714 * For essential trees like root/extent tree, we grab it from fs_info directly.
1715 * For subvolume trees, we check the cached filesystem roots first. If not
1716 * found, then read it from disk and add it to cached fs roots.
1717 *
1718 * Caller should release the root by calling btrfs_put_root() after the usage.
1719 *
1720 * NOTE: Reloc and log trees can't be read by this function as they share the
1721 *	 same root objectid.
1722 *
1723 * @objectid:	root id
1724 * @anon_dev:	preallocated anonymous block device number for new roots,
1725 * 		pass 0 for new allocation.
1726 * @check_ref:	whether to check root item references, If true, return -ENOENT
1727 *		for orphan roots
1728 */
1729static struct btrfs_root *btrfs_get_root_ref(struct btrfs_fs_info *fs_info,
1730					     u64 objectid, dev_t anon_dev,
1731					     bool check_ref)
1732{
1733	struct btrfs_root *root;
1734	struct btrfs_path *path;
1735	struct btrfs_key key;
1736	int ret;
1737
1738	root = btrfs_get_global_root(fs_info, objectid);
1739	if (root)
1740		return root;
 
 
 
 
 
 
 
 
 
 
1741again:
1742	root = btrfs_lookup_fs_root(fs_info, objectid);
1743	if (root) {
1744		/* Shouldn't get preallocated anon_dev for cached roots */
1745		ASSERT(!anon_dev);
 
 
 
 
 
 
 
 
 
1746		if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1747			btrfs_put_root(root);
1748			return ERR_PTR(-ENOENT);
1749		}
1750		return root;
1751	}
1752
1753	key.objectid = objectid;
1754	key.type = BTRFS_ROOT_ITEM_KEY;
1755	key.offset = (u64)-1;
1756	root = btrfs_read_tree_root(fs_info->tree_root, &key);
1757	if (IS_ERR(root))
1758		return root;
1759
1760	if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1761		ret = -ENOENT;
1762		goto fail;
1763	}
1764
1765	ret = btrfs_init_fs_root(root, anon_dev);
1766	if (ret)
1767		goto fail;
1768
1769	path = btrfs_alloc_path();
1770	if (!path) {
1771		ret = -ENOMEM;
1772		goto fail;
1773	}
1774	key.objectid = BTRFS_ORPHAN_OBJECTID;
1775	key.type = BTRFS_ORPHAN_ITEM_KEY;
1776	key.offset = objectid;
1777
1778	ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
1779	btrfs_free_path(path);
1780	if (ret < 0)
1781		goto fail;
1782	if (ret == 0)
1783		set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state);
1784
1785	ret = btrfs_insert_fs_root(fs_info, root);
1786	if (ret) {
1787		if (ret == -EEXIST) {
1788			btrfs_put_root(root);
1789			goto again;
1790		}
1791		goto fail;
1792	}
1793	return root;
1794fail:
1795	/*
1796	 * If our caller provided us an anonymous device, then it's his
1797	 * responsibility to free it in case we fail. So we have to set our
1798	 * root's anon_dev to 0 to avoid a double free, once by btrfs_put_root()
1799	 * and once again by our caller.
1800	 */
1801	if (anon_dev)
1802		root->anon_dev = 0;
1803	btrfs_put_root(root);
1804	return ERR_PTR(ret);
1805}
1806
1807/*
1808 * Get in-memory reference of a root structure
1809 *
1810 * @objectid:	tree objectid
1811 * @check_ref:	if set, verify that the tree exists and the item has at least
1812 *		one reference
1813 */
1814struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
1815				     u64 objectid, bool check_ref)
1816{
1817	return btrfs_get_root_ref(fs_info, objectid, 0, check_ref);
1818}
1819
1820/*
1821 * Get in-memory reference of a root structure, created as new, optionally pass
1822 * the anonymous block device id
1823 *
1824 * @objectid:	tree objectid
1825 * @anon_dev:	if zero, allocate a new anonymous block device or use the
1826 *		parameter value
1827 */
1828struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
1829					 u64 objectid, dev_t anon_dev)
1830{
1831	return btrfs_get_root_ref(fs_info, objectid, anon_dev, true);
1832}
1833
1834/*
1835 * btrfs_get_fs_root_commit_root - return a root for the given objectid
 
1836 * @fs_info:	the fs_info
1837 * @objectid:	the objectid we need to lookup
1838 *
1839 * This is exclusively used for backref walking, and exists specifically because
1840 * of how qgroups does lookups.  Qgroups will do a backref lookup at delayed ref
1841 * creation time, which means we may have to read the tree_root in order to look
1842 * up a fs root that is not in memory.  If the root is not in memory we will
1843 * read the tree root commit root and look up the fs root from there.  This is a
1844 * temporary root, it will not be inserted into the radix tree as it doesn't
1845 * have the most uptodate information, it'll simply be discarded once the
1846 * backref code is finished using the root.
1847 */
1848struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
1849						 struct btrfs_path *path,
1850						 u64 objectid)
1851{
1852	struct btrfs_root *root;
1853	struct btrfs_key key;
1854
1855	ASSERT(path->search_commit_root && path->skip_locking);
1856
1857	/*
1858	 * This can return -ENOENT if we ask for a root that doesn't exist, but
1859	 * since this is called via the backref walking code we won't be looking
1860	 * up a root that doesn't exist, unless there's corruption.  So if root
1861	 * != NULL just return it.
1862	 */
1863	root = btrfs_get_global_root(fs_info, objectid);
1864	if (root)
1865		return root;
1866
1867	root = btrfs_lookup_fs_root(fs_info, objectid);
1868	if (root)
1869		return root;
1870
1871	key.objectid = objectid;
1872	key.type = BTRFS_ROOT_ITEM_KEY;
1873	key.offset = (u64)-1;
1874	root = read_tree_root_path(fs_info->tree_root, path, &key);
1875	btrfs_release_path(path);
1876
1877	return root;
1878}
1879
1880static int cleaner_kthread(void *arg)
1881{
1882	struct btrfs_fs_info *fs_info = arg;
1883	int again;
1884
1885	while (1) {
1886		again = 0;
1887
1888		set_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1889
1890		/* Make the cleaner go to sleep early. */
1891		if (btrfs_need_cleaner_sleep(fs_info))
1892			goto sleep;
1893
1894		/*
1895		 * Do not do anything if we might cause open_ctree() to block
1896		 * before we have finished mounting the filesystem.
1897		 */
1898		if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags))
1899			goto sleep;
1900
1901		if (!mutex_trylock(&fs_info->cleaner_mutex))
1902			goto sleep;
1903
1904		/*
1905		 * Avoid the problem that we change the status of the fs
1906		 * during the above check and trylock.
1907		 */
1908		if (btrfs_need_cleaner_sleep(fs_info)) {
1909			mutex_unlock(&fs_info->cleaner_mutex);
1910			goto sleep;
1911		}
1912
 
 
 
1913		btrfs_run_delayed_iputs(fs_info);
1914
1915		again = btrfs_clean_one_deleted_snapshot(fs_info);
1916		mutex_unlock(&fs_info->cleaner_mutex);
1917
1918		/*
1919		 * The defragger has dealt with the R/O remount and umount,
1920		 * needn't do anything special here.
1921		 */
1922		btrfs_run_defrag_inodes(fs_info);
1923
1924		/*
1925		 * Acquires fs_info->reclaim_bgs_lock to avoid racing
1926		 * with relocation (btrfs_relocate_chunk) and relocation
1927		 * acquires fs_info->cleaner_mutex (btrfs_relocate_block_group)
1928		 * after acquiring fs_info->reclaim_bgs_lock. So we
1929		 * can't hold, nor need to, fs_info->cleaner_mutex when deleting
1930		 * unused block groups.
1931		 */
1932		btrfs_delete_unused_bgs(fs_info);
1933
1934		/*
1935		 * Reclaim block groups in the reclaim_bgs list after we deleted
1936		 * all unused block_groups. This possibly gives us some more free
1937		 * space.
1938		 */
1939		btrfs_reclaim_bgs(fs_info);
1940sleep:
1941		clear_and_wake_up_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1942		if (kthread_should_park())
1943			kthread_parkme();
1944		if (kthread_should_stop())
1945			return 0;
1946		if (!again) {
1947			set_current_state(TASK_INTERRUPTIBLE);
1948			schedule();
1949			__set_current_state(TASK_RUNNING);
1950		}
1951	}
1952}
1953
1954static int transaction_kthread(void *arg)
1955{
1956	struct btrfs_root *root = arg;
1957	struct btrfs_fs_info *fs_info = root->fs_info;
1958	struct btrfs_trans_handle *trans;
1959	struct btrfs_transaction *cur;
1960	u64 transid;
1961	time64_t delta;
1962	unsigned long delay;
1963	bool cannot_commit;
1964
1965	do {
1966		cannot_commit = false;
1967		delay = msecs_to_jiffies(fs_info->commit_interval * 1000);
1968		mutex_lock(&fs_info->transaction_kthread_mutex);
1969
1970		spin_lock(&fs_info->trans_lock);
1971		cur = fs_info->running_transaction;
1972		if (!cur) {
1973			spin_unlock(&fs_info->trans_lock);
1974			goto sleep;
1975		}
1976
1977		delta = ktime_get_seconds() - cur->start_time;
1978		if (!test_and_clear_bit(BTRFS_FS_COMMIT_TRANS, &fs_info->flags) &&
1979		    cur->state < TRANS_STATE_COMMIT_START &&
1980		    delta < fs_info->commit_interval) {
1981			spin_unlock(&fs_info->trans_lock);
1982			delay -= msecs_to_jiffies((delta - 1) * 1000);
1983			delay = min(delay,
1984				    msecs_to_jiffies(fs_info->commit_interval * 1000));
1985			goto sleep;
1986		}
1987		transid = cur->transid;
1988		spin_unlock(&fs_info->trans_lock);
1989
1990		/* If the file system is aborted, this will always fail. */
1991		trans = btrfs_attach_transaction(root);
1992		if (IS_ERR(trans)) {
1993			if (PTR_ERR(trans) != -ENOENT)
1994				cannot_commit = true;
1995			goto sleep;
1996		}
1997		if (transid == trans->transid) {
1998			btrfs_commit_transaction(trans);
1999		} else {
2000			btrfs_end_transaction(trans);
2001		}
2002sleep:
2003		wake_up_process(fs_info->cleaner_kthread);
2004		mutex_unlock(&fs_info->transaction_kthread_mutex);
2005
2006		if (BTRFS_FS_ERROR(fs_info))
2007			btrfs_cleanup_transaction(fs_info);
2008		if (!kthread_should_stop() &&
2009				(!btrfs_transaction_blocked(fs_info) ||
2010				 cannot_commit))
2011			schedule_timeout_interruptible(delay);
2012	} while (!kthread_should_stop());
2013	return 0;
2014}
2015
2016/*
2017 * This will find the highest generation in the array of root backups.  The
2018 * index of the highest array is returned, or -EINVAL if we can't find
2019 * anything.
2020 *
2021 * We check to make sure the array is valid by comparing the
2022 * generation of the latest  root in the array with the generation
2023 * in the super block.  If they don't match we pitch it.
2024 */
2025static int find_newest_super_backup(struct btrfs_fs_info *info)
2026{
2027	const u64 newest_gen = btrfs_super_generation(info->super_copy);
2028	u64 cur;
2029	struct btrfs_root_backup *root_backup;
2030	int i;
2031
2032	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
2033		root_backup = info->super_copy->super_roots + i;
2034		cur = btrfs_backup_tree_root_gen(root_backup);
2035		if (cur == newest_gen)
2036			return i;
2037	}
2038
2039	return -EINVAL;
2040}
2041
2042/*
2043 * copy all the root pointers into the super backup array.
2044 * this will bump the backup pointer by one when it is
2045 * done
2046 */
2047static void backup_super_roots(struct btrfs_fs_info *info)
2048{
2049	const int next_backup = info->backup_root_index;
2050	struct btrfs_root_backup *root_backup;
2051
2052	root_backup = info->super_for_commit->super_roots + next_backup;
2053
2054	/*
2055	 * make sure all of our padding and empty slots get zero filled
2056	 * regardless of which ones we use today
2057	 */
2058	memset(root_backup, 0, sizeof(*root_backup));
2059
2060	info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
2061
2062	btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
2063	btrfs_set_backup_tree_root_gen(root_backup,
2064			       btrfs_header_generation(info->tree_root->node));
2065
2066	btrfs_set_backup_tree_root_level(root_backup,
2067			       btrfs_header_level(info->tree_root->node));
2068
2069	btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
2070	btrfs_set_backup_chunk_root_gen(root_backup,
2071			       btrfs_header_generation(info->chunk_root->node));
2072	btrfs_set_backup_chunk_root_level(root_backup,
2073			       btrfs_header_level(info->chunk_root->node));
2074
2075	if (!btrfs_fs_compat_ro(info, BLOCK_GROUP_TREE)) {
2076		struct btrfs_root *extent_root = btrfs_extent_root(info, 0);
2077		struct btrfs_root *csum_root = btrfs_csum_root(info, 0);
2078
2079		btrfs_set_backup_extent_root(root_backup,
2080					     extent_root->node->start);
2081		btrfs_set_backup_extent_root_gen(root_backup,
2082				btrfs_header_generation(extent_root->node));
2083		btrfs_set_backup_extent_root_level(root_backup,
2084					btrfs_header_level(extent_root->node));
2085
2086		btrfs_set_backup_csum_root(root_backup, csum_root->node->start);
2087		btrfs_set_backup_csum_root_gen(root_backup,
2088					       btrfs_header_generation(csum_root->node));
2089		btrfs_set_backup_csum_root_level(root_backup,
2090						 btrfs_header_level(csum_root->node));
2091	}
2092
2093	/*
2094	 * we might commit during log recovery, which happens before we set
2095	 * the fs_root.  Make sure it is valid before we fill it in.
2096	 */
2097	if (info->fs_root && info->fs_root->node) {
2098		btrfs_set_backup_fs_root(root_backup,
2099					 info->fs_root->node->start);
2100		btrfs_set_backup_fs_root_gen(root_backup,
2101			       btrfs_header_generation(info->fs_root->node));
2102		btrfs_set_backup_fs_root_level(root_backup,
2103			       btrfs_header_level(info->fs_root->node));
2104	}
2105
2106	btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
2107	btrfs_set_backup_dev_root_gen(root_backup,
2108			       btrfs_header_generation(info->dev_root->node));
2109	btrfs_set_backup_dev_root_level(root_backup,
2110				       btrfs_header_level(info->dev_root->node));
2111
2112	btrfs_set_backup_total_bytes(root_backup,
2113			     btrfs_super_total_bytes(info->super_copy));
2114	btrfs_set_backup_bytes_used(root_backup,
2115			     btrfs_super_bytes_used(info->super_copy));
2116	btrfs_set_backup_num_devices(root_backup,
2117			     btrfs_super_num_devices(info->super_copy));
2118
2119	/*
2120	 * if we don't copy this out to the super_copy, it won't get remembered
2121	 * for the next commit
2122	 */
2123	memcpy(&info->super_copy->super_roots,
2124	       &info->super_for_commit->super_roots,
2125	       sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
2126}
2127
2128/*
2129 * read_backup_root - Reads a backup root based on the passed priority. Prio 0
2130 * is the newest, prio 1/2/3 are 2nd newest/3rd newest/4th (oldest) backup roots
2131 *
2132 * fs_info - filesystem whose backup roots need to be read
2133 * priority - priority of backup root required
2134 *
2135 * Returns backup root index on success and -EINVAL otherwise.
2136 */
2137static int read_backup_root(struct btrfs_fs_info *fs_info, u8 priority)
2138{
2139	int backup_index = find_newest_super_backup(fs_info);
2140	struct btrfs_super_block *super = fs_info->super_copy;
2141	struct btrfs_root_backup *root_backup;
2142
2143	if (priority < BTRFS_NUM_BACKUP_ROOTS && backup_index >= 0) {
2144		if (priority == 0)
2145			return backup_index;
2146
2147		backup_index = backup_index + BTRFS_NUM_BACKUP_ROOTS - priority;
2148		backup_index %= BTRFS_NUM_BACKUP_ROOTS;
2149	} else {
2150		return -EINVAL;
2151	}
2152
2153	root_backup = super->super_roots + backup_index;
2154
2155	btrfs_set_super_generation(super,
2156				   btrfs_backup_tree_root_gen(root_backup));
2157	btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
2158	btrfs_set_super_root_level(super,
2159				   btrfs_backup_tree_root_level(root_backup));
2160	btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
2161
2162	/*
2163	 * Fixme: the total bytes and num_devices need to match or we should
2164	 * need a fsck
2165	 */
2166	btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
2167	btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
2168
2169	return backup_index;
2170}
2171
2172/* helper to cleanup workers */
2173static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
2174{
2175	btrfs_destroy_workqueue(fs_info->fixup_workers);
2176	btrfs_destroy_workqueue(fs_info->delalloc_workers);
2177	btrfs_destroy_workqueue(fs_info->hipri_workers);
2178	btrfs_destroy_workqueue(fs_info->workers);
2179	if (fs_info->endio_workers)
2180		destroy_workqueue(fs_info->endio_workers);
2181	if (fs_info->rmw_workers)
2182		destroy_workqueue(fs_info->rmw_workers);
2183	if (fs_info->compressed_write_workers)
2184		destroy_workqueue(fs_info->compressed_write_workers);
2185	btrfs_destroy_workqueue(fs_info->endio_write_workers);
2186	btrfs_destroy_workqueue(fs_info->endio_freespace_worker);
2187	btrfs_destroy_workqueue(fs_info->delayed_workers);
2188	btrfs_destroy_workqueue(fs_info->caching_workers);
2189	btrfs_destroy_workqueue(fs_info->flush_workers);
2190	btrfs_destroy_workqueue(fs_info->qgroup_rescan_workers);
2191	if (fs_info->discard_ctl.discard_workers)
2192		destroy_workqueue(fs_info->discard_ctl.discard_workers);
2193	/*
2194	 * Now that all other work queues are destroyed, we can safely destroy
2195	 * the queues used for metadata I/O, since tasks from those other work
2196	 * queues can do metadata I/O operations.
2197	 */
2198	if (fs_info->endio_meta_workers)
2199		destroy_workqueue(fs_info->endio_meta_workers);
2200}
2201
2202static void free_root_extent_buffers(struct btrfs_root *root)
2203{
2204	if (root) {
2205		free_extent_buffer(root->node);
2206		free_extent_buffer(root->commit_root);
2207		root->node = NULL;
2208		root->commit_root = NULL;
2209	}
2210}
2211
2212static void free_global_root_pointers(struct btrfs_fs_info *fs_info)
2213{
2214	struct btrfs_root *root, *tmp;
2215
2216	rbtree_postorder_for_each_entry_safe(root, tmp,
2217					     &fs_info->global_root_tree,
2218					     rb_node)
2219		free_root_extent_buffers(root);
2220}
2221
2222/* helper to cleanup tree roots */
2223static void free_root_pointers(struct btrfs_fs_info *info, bool free_chunk_root)
2224{
2225	free_root_extent_buffers(info->tree_root);
2226
2227	free_global_root_pointers(info);
2228	free_root_extent_buffers(info->dev_root);
2229	free_root_extent_buffers(info->quota_root);
2230	free_root_extent_buffers(info->uuid_root);
2231	free_root_extent_buffers(info->fs_root);
2232	free_root_extent_buffers(info->data_reloc_root);
2233	free_root_extent_buffers(info->block_group_root);
 
2234	if (free_chunk_root)
2235		free_root_extent_buffers(info->chunk_root);
2236}
2237
2238void btrfs_put_root(struct btrfs_root *root)
2239{
2240	if (!root)
2241		return;
2242
2243	if (refcount_dec_and_test(&root->refs)) {
2244		WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
2245		WARN_ON(test_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state));
2246		if (root->anon_dev)
2247			free_anon_bdev(root->anon_dev);
2248		btrfs_drew_lock_destroy(&root->snapshot_lock);
2249		free_root_extent_buffers(root);
2250#ifdef CONFIG_BTRFS_DEBUG
2251		spin_lock(&root->fs_info->fs_roots_radix_lock);
2252		list_del_init(&root->leak_list);
2253		spin_unlock(&root->fs_info->fs_roots_radix_lock);
2254#endif
2255		kfree(root);
2256	}
2257}
2258
2259void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info)
2260{
2261	int ret;
2262	struct btrfs_root *gang[8];
2263	int i;
2264
2265	while (!list_empty(&fs_info->dead_roots)) {
2266		gang[0] = list_entry(fs_info->dead_roots.next,
2267				     struct btrfs_root, root_list);
2268		list_del(&gang[0]->root_list);
2269
2270		if (test_bit(BTRFS_ROOT_IN_RADIX, &gang[0]->state))
2271			btrfs_drop_and_free_fs_root(fs_info, gang[0]);
2272		btrfs_put_root(gang[0]);
2273	}
2274
2275	while (1) {
2276		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2277					     (void **)gang, 0,
2278					     ARRAY_SIZE(gang));
2279		if (!ret)
2280			break;
2281		for (i = 0; i < ret; i++)
2282			btrfs_drop_and_free_fs_root(fs_info, gang[i]);
2283	}
2284}
2285
2286static void btrfs_init_scrub(struct btrfs_fs_info *fs_info)
2287{
2288	mutex_init(&fs_info->scrub_lock);
2289	atomic_set(&fs_info->scrubs_running, 0);
2290	atomic_set(&fs_info->scrub_pause_req, 0);
2291	atomic_set(&fs_info->scrubs_paused, 0);
2292	atomic_set(&fs_info->scrub_cancel_req, 0);
2293	init_waitqueue_head(&fs_info->scrub_pause_wait);
2294	refcount_set(&fs_info->scrub_workers_refcnt, 0);
2295}
2296
2297static void btrfs_init_balance(struct btrfs_fs_info *fs_info)
2298{
2299	spin_lock_init(&fs_info->balance_lock);
2300	mutex_init(&fs_info->balance_mutex);
2301	atomic_set(&fs_info->balance_pause_req, 0);
2302	atomic_set(&fs_info->balance_cancel_req, 0);
2303	fs_info->balance_ctl = NULL;
2304	init_waitqueue_head(&fs_info->balance_wait_q);
2305	atomic_set(&fs_info->reloc_cancel_req, 0);
2306}
2307
2308static void btrfs_init_btree_inode(struct btrfs_fs_info *fs_info)
2309{
2310	struct inode *inode = fs_info->btree_inode;
2311	unsigned long hash = btrfs_inode_hash(BTRFS_BTREE_INODE_OBJECTID,
2312					      fs_info->tree_root);
 
 
 
 
 
2313
2314	inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
2315	set_nlink(inode, 1);
2316	/*
2317	 * we set the i_size on the btree inode to the max possible int.
2318	 * the real end of the address space is determined by all of
2319	 * the devices in the system
2320	 */
2321	inode->i_size = OFFSET_MAX;
2322	inode->i_mapping->a_ops = &btree_aops;
 
2323
2324	RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
2325	extent_io_tree_init(fs_info, &BTRFS_I(inode)->io_tree,
2326			    IO_TREE_BTREE_INODE_IO);
2327	extent_map_tree_init(&BTRFS_I(inode)->extent_tree);
2328
2329	BTRFS_I(inode)->root = btrfs_grab_root(fs_info->tree_root);
2330	BTRFS_I(inode)->location.objectid = BTRFS_BTREE_INODE_OBJECTID;
2331	BTRFS_I(inode)->location.type = 0;
2332	BTRFS_I(inode)->location.offset = 0;
2333	set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
2334	__insert_inode_hash(inode, hash);
 
 
 
2335}
2336
2337static void btrfs_init_dev_replace_locks(struct btrfs_fs_info *fs_info)
2338{
2339	mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount);
2340	init_rwsem(&fs_info->dev_replace.rwsem);
2341	init_waitqueue_head(&fs_info->dev_replace.replace_wait);
2342}
2343
2344static void btrfs_init_qgroup(struct btrfs_fs_info *fs_info)
2345{
2346	spin_lock_init(&fs_info->qgroup_lock);
2347	mutex_init(&fs_info->qgroup_ioctl_lock);
2348	fs_info->qgroup_tree = RB_ROOT;
2349	INIT_LIST_HEAD(&fs_info->dirty_qgroups);
2350	fs_info->qgroup_seq = 1;
2351	fs_info->qgroup_ulist = NULL;
2352	fs_info->qgroup_rescan_running = false;
2353	fs_info->qgroup_drop_subtree_thres = BTRFS_MAX_LEVEL;
2354	mutex_init(&fs_info->qgroup_rescan_lock);
2355}
2356
2357static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info)
2358{
2359	u32 max_active = fs_info->thread_pool_size;
2360	unsigned int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND;
 
2361
2362	fs_info->workers =
2363		btrfs_alloc_workqueue(fs_info, "worker", flags, max_active, 16);
2364	fs_info->hipri_workers =
2365		btrfs_alloc_workqueue(fs_info, "worker-high",
2366				      flags | WQ_HIGHPRI, max_active, 16);
2367
2368	fs_info->delalloc_workers =
2369		btrfs_alloc_workqueue(fs_info, "delalloc",
2370				      flags, max_active, 2);
2371
2372	fs_info->flush_workers =
2373		btrfs_alloc_workqueue(fs_info, "flush_delalloc",
2374				      flags, max_active, 0);
2375
2376	fs_info->caching_workers =
2377		btrfs_alloc_workqueue(fs_info, "cache", flags, max_active, 0);
2378
2379	fs_info->fixup_workers =
2380		btrfs_alloc_workqueue(fs_info, "fixup", flags, 1, 0);
2381
2382	fs_info->endio_workers =
2383		alloc_workqueue("btrfs-endio", flags, max_active);
2384	fs_info->endio_meta_workers =
2385		alloc_workqueue("btrfs-endio-meta", flags, max_active);
2386	fs_info->rmw_workers = alloc_workqueue("btrfs-rmw", flags, max_active);
2387	fs_info->endio_write_workers =
2388		btrfs_alloc_workqueue(fs_info, "endio-write", flags,
2389				      max_active, 2);
2390	fs_info->compressed_write_workers =
2391		alloc_workqueue("btrfs-compressed-write", flags, max_active);
2392	fs_info->endio_freespace_worker =
2393		btrfs_alloc_workqueue(fs_info, "freespace-write", flags,
2394				      max_active, 0);
2395	fs_info->delayed_workers =
2396		btrfs_alloc_workqueue(fs_info, "delayed-meta", flags,
2397				      max_active, 0);
2398	fs_info->qgroup_rescan_workers =
2399		btrfs_alloc_workqueue(fs_info, "qgroup-rescan", flags, 1, 0);
 
2400	fs_info->discard_ctl.discard_workers =
2401		alloc_workqueue("btrfs_discard", WQ_UNBOUND | WQ_FREEZABLE, 1);
2402
2403	if (!(fs_info->workers && fs_info->hipri_workers &&
2404	      fs_info->delalloc_workers && fs_info->flush_workers &&
2405	      fs_info->endio_workers && fs_info->endio_meta_workers &&
2406	      fs_info->compressed_write_workers &&
2407	      fs_info->endio_write_workers &&
2408	      fs_info->endio_freespace_worker && fs_info->rmw_workers &&
2409	      fs_info->caching_workers && fs_info->fixup_workers &&
2410	      fs_info->delayed_workers && fs_info->qgroup_rescan_workers &&
2411	      fs_info->discard_ctl.discard_workers)) {
2412		return -ENOMEM;
2413	}
2414
2415	return 0;
2416}
2417
2418static int btrfs_init_csum_hash(struct btrfs_fs_info *fs_info, u16 csum_type)
2419{
2420	struct crypto_shash *csum_shash;
2421	const char *csum_driver = btrfs_super_csum_driver(csum_type);
2422
2423	csum_shash = crypto_alloc_shash(csum_driver, 0, 0);
2424
2425	if (IS_ERR(csum_shash)) {
2426		btrfs_err(fs_info, "error allocating %s hash for checksum",
2427			  csum_driver);
2428		return PTR_ERR(csum_shash);
2429	}
2430
2431	fs_info->csum_shash = csum_shash;
2432
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2433	btrfs_info(fs_info, "using %s (%s) checksum algorithm",
2434			btrfs_super_csum_name(csum_type),
2435			crypto_shash_driver_name(csum_shash));
2436	return 0;
2437}
2438
2439static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
2440			    struct btrfs_fs_devices *fs_devices)
2441{
2442	int ret;
2443	struct btrfs_tree_parent_check check = { 0 };
2444	struct btrfs_root *log_tree_root;
2445	struct btrfs_super_block *disk_super = fs_info->super_copy;
2446	u64 bytenr = btrfs_super_log_root(disk_super);
2447	int level = btrfs_super_log_root_level(disk_super);
2448
2449	if (fs_devices->rw_devices == 0) {
2450		btrfs_warn(fs_info, "log replay required on RO media");
2451		return -EIO;
2452	}
2453
2454	log_tree_root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID,
2455					 GFP_KERNEL);
2456	if (!log_tree_root)
2457		return -ENOMEM;
2458
2459	check.level = level;
2460	check.transid = fs_info->generation + 1;
2461	check.owner_root = BTRFS_TREE_LOG_OBJECTID;
2462	log_tree_root->node = read_tree_block(fs_info, bytenr, &check);
2463	if (IS_ERR(log_tree_root->node)) {
2464		btrfs_warn(fs_info, "failed to read log tree");
2465		ret = PTR_ERR(log_tree_root->node);
2466		log_tree_root->node = NULL;
2467		btrfs_put_root(log_tree_root);
2468		return ret;
2469	}
2470	if (!extent_buffer_uptodate(log_tree_root->node)) {
2471		btrfs_err(fs_info, "failed to read log tree");
2472		btrfs_put_root(log_tree_root);
2473		return -EIO;
2474	}
2475
2476	/* returns with log_tree_root freed on success */
2477	ret = btrfs_recover_log_trees(log_tree_root);
2478	if (ret) {
2479		btrfs_handle_fs_error(fs_info, ret,
2480				      "Failed to recover log tree");
2481		btrfs_put_root(log_tree_root);
2482		return ret;
2483	}
2484
2485	if (sb_rdonly(fs_info->sb)) {
2486		ret = btrfs_commit_super(fs_info);
2487		if (ret)
2488			return ret;
2489	}
2490
2491	return 0;
2492}
2493
2494static int load_global_roots_objectid(struct btrfs_root *tree_root,
2495				      struct btrfs_path *path, u64 objectid,
2496				      const char *name)
2497{
2498	struct btrfs_fs_info *fs_info = tree_root->fs_info;
2499	struct btrfs_root *root;
2500	u64 max_global_id = 0;
2501	int ret;
2502	struct btrfs_key key = {
2503		.objectid = objectid,
2504		.type = BTRFS_ROOT_ITEM_KEY,
2505		.offset = 0,
2506	};
2507	bool found = false;
2508
2509	/* If we have IGNOREDATACSUMS skip loading these roots. */
2510	if (objectid == BTRFS_CSUM_TREE_OBJECTID &&
2511	    btrfs_test_opt(fs_info, IGNOREDATACSUMS)) {
2512		set_bit(BTRFS_FS_STATE_NO_CSUMS, &fs_info->fs_state);
2513		return 0;
2514	}
2515
2516	while (1) {
2517		ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0);
2518		if (ret < 0)
2519			break;
2520
2521		if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
2522			ret = btrfs_next_leaf(tree_root, path);
2523			if (ret) {
2524				if (ret > 0)
2525					ret = 0;
2526				break;
2527			}
2528		}
2529		ret = 0;
2530
2531		btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
2532		if (key.objectid != objectid)
2533			break;
2534		btrfs_release_path(path);
2535
2536		/*
2537		 * Just worry about this for extent tree, it'll be the same for
2538		 * everybody.
2539		 */
2540		if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
2541			max_global_id = max(max_global_id, key.offset);
2542
2543		found = true;
2544		root = read_tree_root_path(tree_root, path, &key);
2545		if (IS_ERR(root)) {
2546			if (!btrfs_test_opt(fs_info, IGNOREBADROOTS))
2547				ret = PTR_ERR(root);
2548			break;
2549		}
2550		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2551		ret = btrfs_global_root_insert(root);
2552		if (ret) {
2553			btrfs_put_root(root);
2554			break;
2555		}
2556		key.offset++;
2557	}
2558	btrfs_release_path(path);
2559
2560	if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
2561		fs_info->nr_global_roots = max_global_id + 1;
2562
2563	if (!found || ret) {
2564		if (objectid == BTRFS_CSUM_TREE_OBJECTID)
2565			set_bit(BTRFS_FS_STATE_NO_CSUMS, &fs_info->fs_state);
2566
2567		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS))
2568			ret = ret ? ret : -ENOENT;
2569		else
2570			ret = 0;
2571		btrfs_err(fs_info, "failed to load root %s", name);
2572	}
2573	return ret;
2574}
2575
2576static int load_global_roots(struct btrfs_root *tree_root)
2577{
2578	struct btrfs_path *path;
2579	int ret = 0;
2580
2581	path = btrfs_alloc_path();
2582	if (!path)
2583		return -ENOMEM;
2584
2585	ret = load_global_roots_objectid(tree_root, path,
2586					 BTRFS_EXTENT_TREE_OBJECTID, "extent");
2587	if (ret)
2588		goto out;
2589	ret = load_global_roots_objectid(tree_root, path,
2590					 BTRFS_CSUM_TREE_OBJECTID, "csum");
2591	if (ret)
2592		goto out;
2593	if (!btrfs_fs_compat_ro(tree_root->fs_info, FREE_SPACE_TREE))
2594		goto out;
2595	ret = load_global_roots_objectid(tree_root, path,
2596					 BTRFS_FREE_SPACE_TREE_OBJECTID,
2597					 "free space");
2598out:
2599	btrfs_free_path(path);
2600	return ret;
2601}
2602
2603static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
2604{
2605	struct btrfs_root *tree_root = fs_info->tree_root;
2606	struct btrfs_root *root;
2607	struct btrfs_key location;
2608	int ret;
2609
2610	BUG_ON(!fs_info->tree_root);
2611
2612	ret = load_global_roots(tree_root);
2613	if (ret)
2614		return ret;
2615
2616	location.type = BTRFS_ROOT_ITEM_KEY;
2617	location.offset = 0;
2618
2619	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE)) {
2620		location.objectid = BTRFS_BLOCK_GROUP_TREE_OBJECTID;
2621		root = btrfs_read_tree_root(tree_root, &location);
2622		if (IS_ERR(root)) {
2623			if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2624				ret = PTR_ERR(root);
2625				goto out;
2626			}
2627		} else {
2628			set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2629			fs_info->block_group_root = root;
2630		}
2631	}
2632
2633	location.objectid = BTRFS_DEV_TREE_OBJECTID;
2634	root = btrfs_read_tree_root(tree_root, &location);
2635	if (IS_ERR(root)) {
2636		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2637			ret = PTR_ERR(root);
2638			goto out;
2639		}
2640	} else {
2641		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2642		fs_info->dev_root = root;
2643	}
2644	/* Initialize fs_info for all devices in any case */
2645	ret = btrfs_init_devices_late(fs_info);
2646	if (ret)
2647		goto out;
2648
2649	/*
2650	 * This tree can share blocks with some other fs tree during relocation
2651	 * and we need a proper setup by btrfs_get_fs_root
2652	 */
2653	root = btrfs_get_fs_root(tree_root->fs_info,
2654				 BTRFS_DATA_RELOC_TREE_OBJECTID, true);
2655	if (IS_ERR(root)) {
2656		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2657			ret = PTR_ERR(root);
2658			goto out;
2659		}
2660	} else {
2661		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2662		fs_info->data_reloc_root = root;
2663	}
2664
2665	location.objectid = BTRFS_QUOTA_TREE_OBJECTID;
2666	root = btrfs_read_tree_root(tree_root, &location);
2667	if (!IS_ERR(root)) {
2668		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2669		set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
2670		fs_info->quota_root = root;
2671	}
2672
2673	location.objectid = BTRFS_UUID_TREE_OBJECTID;
2674	root = btrfs_read_tree_root(tree_root, &location);
2675	if (IS_ERR(root)) {
2676		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2677			ret = PTR_ERR(root);
2678			if (ret != -ENOENT)
2679				goto out;
2680		}
2681	} else {
2682		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2683		fs_info->uuid_root = root;
2684	}
2685
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2686	return 0;
2687out:
2688	btrfs_warn(fs_info, "failed to read root (objectid=%llu): %d",
2689		   location.objectid, ret);
2690	return ret;
2691}
2692
2693/*
2694 * Real super block validation
2695 * NOTE: super csum type and incompat features will not be checked here.
2696 *
2697 * @sb:		super block to check
2698 * @mirror_num:	the super block number to check its bytenr:
2699 * 		0	the primary (1st) sb
2700 * 		1, 2	2nd and 3rd backup copy
2701 * 	       -1	skip bytenr check
2702 */
2703int btrfs_validate_super(struct btrfs_fs_info *fs_info,
2704			 struct btrfs_super_block *sb, int mirror_num)
2705{
2706	u64 nodesize = btrfs_super_nodesize(sb);
2707	u64 sectorsize = btrfs_super_sectorsize(sb);
2708	int ret = 0;
2709
2710	if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
2711		btrfs_err(fs_info, "no valid FS found");
2712		ret = -EINVAL;
2713	}
2714	if (btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP) {
2715		btrfs_err(fs_info, "unrecognized or unsupported super flag: %llu",
2716				btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);
2717		ret = -EINVAL;
2718	}
2719	if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
2720		btrfs_err(fs_info, "tree_root level too big: %d >= %d",
2721				btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
2722		ret = -EINVAL;
2723	}
2724	if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
2725		btrfs_err(fs_info, "chunk_root level too big: %d >= %d",
2726				btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
2727		ret = -EINVAL;
2728	}
2729	if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
2730		btrfs_err(fs_info, "log_root level too big: %d >= %d",
2731				btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
2732		ret = -EINVAL;
2733	}
2734
2735	/*
2736	 * Check sectorsize and nodesize first, other check will need it.
2737	 * Check all possible sectorsize(4K, 8K, 16K, 32K, 64K) here.
2738	 */
2739	if (!is_power_of_2(sectorsize) || sectorsize < 4096 ||
2740	    sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2741		btrfs_err(fs_info, "invalid sectorsize %llu", sectorsize);
2742		ret = -EINVAL;
2743	}
2744
2745	/*
2746	 * We only support at most two sectorsizes: 4K and PAGE_SIZE.
2747	 *
2748	 * We can support 16K sectorsize with 64K page size without problem,
2749	 * but such sectorsize/pagesize combination doesn't make much sense.
2750	 * 4K will be our future standard, PAGE_SIZE is supported from the very
2751	 * beginning.
2752	 */
2753	if (sectorsize > PAGE_SIZE || (sectorsize != SZ_4K && sectorsize != PAGE_SIZE)) {
2754		btrfs_err(fs_info,
2755			"sectorsize %llu not yet supported for page size %lu",
2756			sectorsize, PAGE_SIZE);
2757		ret = -EINVAL;
2758	}
2759
2760	if (!is_power_of_2(nodesize) || nodesize < sectorsize ||
2761	    nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2762		btrfs_err(fs_info, "invalid nodesize %llu", nodesize);
2763		ret = -EINVAL;
2764	}
2765	if (nodesize != le32_to_cpu(sb->__unused_leafsize)) {
2766		btrfs_err(fs_info, "invalid leafsize %u, should be %llu",
2767			  le32_to_cpu(sb->__unused_leafsize), nodesize);
2768		ret = -EINVAL;
2769	}
2770
2771	/* Root alignment check */
2772	if (!IS_ALIGNED(btrfs_super_root(sb), sectorsize)) {
2773		btrfs_warn(fs_info, "tree_root block unaligned: %llu",
2774			   btrfs_super_root(sb));
2775		ret = -EINVAL;
2776	}
2777	if (!IS_ALIGNED(btrfs_super_chunk_root(sb), sectorsize)) {
2778		btrfs_warn(fs_info, "chunk_root block unaligned: %llu",
2779			   btrfs_super_chunk_root(sb));
2780		ret = -EINVAL;
2781	}
2782	if (!IS_ALIGNED(btrfs_super_log_root(sb), sectorsize)) {
2783		btrfs_warn(fs_info, "log_root block unaligned: %llu",
2784			   btrfs_super_log_root(sb));
2785		ret = -EINVAL;
2786	}
2787
2788	if (memcmp(fs_info->fs_devices->fsid, fs_info->super_copy->fsid,
2789		   BTRFS_FSID_SIZE)) {
2790		btrfs_err(fs_info,
2791		"superblock fsid doesn't match fsid of fs_devices: %pU != %pU",
2792			fs_info->super_copy->fsid, fs_info->fs_devices->fsid);
2793		ret = -EINVAL;
2794	}
2795
2796	if (btrfs_fs_incompat(fs_info, METADATA_UUID) &&
2797	    memcmp(fs_info->fs_devices->metadata_uuid,
2798		   fs_info->super_copy->metadata_uuid, BTRFS_FSID_SIZE)) {
2799		btrfs_err(fs_info,
2800"superblock metadata_uuid doesn't match metadata uuid of fs_devices: %pU != %pU",
2801			fs_info->super_copy->metadata_uuid,
2802			fs_info->fs_devices->metadata_uuid);
 
 
 
 
 
 
 
2803		ret = -EINVAL;
2804	}
2805
2806	/*
2807	 * Artificial requirement for block-group-tree to force newer features
2808	 * (free-space-tree, no-holes) so the test matrix is smaller.
2809	 */
2810	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE) &&
2811	    (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID) ||
2812	     !btrfs_fs_incompat(fs_info, NO_HOLES))) {
2813		btrfs_err(fs_info,
2814		"block-group-tree feature requires fres-space-tree and no-holes");
2815		ret = -EINVAL;
2816	}
2817
2818	if (memcmp(fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid,
2819		   BTRFS_FSID_SIZE) != 0) {
2820		btrfs_err(fs_info,
2821			"dev_item UUID does not match metadata fsid: %pU != %pU",
2822			fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid);
2823		ret = -EINVAL;
2824	}
2825
2826	/*
2827	 * Hint to catch really bogus numbers, bitflips or so, more exact checks are
2828	 * done later
2829	 */
2830	if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) {
2831		btrfs_err(fs_info, "bytes_used is too small %llu",
2832			  btrfs_super_bytes_used(sb));
2833		ret = -EINVAL;
2834	}
2835	if (!is_power_of_2(btrfs_super_stripesize(sb))) {
2836		btrfs_err(fs_info, "invalid stripesize %u",
2837			  btrfs_super_stripesize(sb));
2838		ret = -EINVAL;
2839	}
2840	if (btrfs_super_num_devices(sb) > (1UL << 31))
2841		btrfs_warn(fs_info, "suspicious number of devices: %llu",
2842			   btrfs_super_num_devices(sb));
2843	if (btrfs_super_num_devices(sb) == 0) {
2844		btrfs_err(fs_info, "number of devices is 0");
2845		ret = -EINVAL;
2846	}
2847
2848	if (mirror_num >= 0 &&
2849	    btrfs_super_bytenr(sb) != btrfs_sb_offset(mirror_num)) {
2850		btrfs_err(fs_info, "super offset mismatch %llu != %u",
2851			  btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET);
2852		ret = -EINVAL;
2853	}
2854
2855	/*
2856	 * Obvious sys_chunk_array corruptions, it must hold at least one key
2857	 * and one chunk
2858	 */
2859	if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
2860		btrfs_err(fs_info, "system chunk array too big %u > %u",
2861			  btrfs_super_sys_array_size(sb),
2862			  BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
2863		ret = -EINVAL;
2864	}
2865	if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
2866			+ sizeof(struct btrfs_chunk)) {
2867		btrfs_err(fs_info, "system chunk array too small %u < %zu",
2868			  btrfs_super_sys_array_size(sb),
2869			  sizeof(struct btrfs_disk_key)
2870			  + sizeof(struct btrfs_chunk));
2871		ret = -EINVAL;
2872	}
2873
2874	/*
2875	 * The generation is a global counter, we'll trust it more than the others
2876	 * but it's still possible that it's the one that's wrong.
2877	 */
2878	if (btrfs_super_generation(sb) < btrfs_super_chunk_root_generation(sb))
2879		btrfs_warn(fs_info,
2880			"suspicious: generation < chunk_root_generation: %llu < %llu",
2881			btrfs_super_generation(sb),
2882			btrfs_super_chunk_root_generation(sb));
2883	if (btrfs_super_generation(sb) < btrfs_super_cache_generation(sb)
2884	    && btrfs_super_cache_generation(sb) != (u64)-1)
2885		btrfs_warn(fs_info,
2886			"suspicious: generation < cache_generation: %llu < %llu",
2887			btrfs_super_generation(sb),
2888			btrfs_super_cache_generation(sb));
2889
2890	return ret;
2891}
2892
2893/*
2894 * Validation of super block at mount time.
2895 * Some checks already done early at mount time, like csum type and incompat
2896 * flags will be skipped.
2897 */
2898static int btrfs_validate_mount_super(struct btrfs_fs_info *fs_info)
2899{
2900	return btrfs_validate_super(fs_info, fs_info->super_copy, 0);
2901}
2902
2903/*
2904 * Validation of super block at write time.
2905 * Some checks like bytenr check will be skipped as their values will be
2906 * overwritten soon.
2907 * Extra checks like csum type and incompat flags will be done here.
2908 */
2909static int btrfs_validate_write_super(struct btrfs_fs_info *fs_info,
2910				      struct btrfs_super_block *sb)
2911{
2912	int ret;
2913
2914	ret = btrfs_validate_super(fs_info, sb, -1);
2915	if (ret < 0)
2916		goto out;
2917	if (!btrfs_supported_super_csum(btrfs_super_csum_type(sb))) {
2918		ret = -EUCLEAN;
2919		btrfs_err(fs_info, "invalid csum type, has %u want %u",
2920			  btrfs_super_csum_type(sb), BTRFS_CSUM_TYPE_CRC32);
2921		goto out;
2922	}
2923	if (btrfs_super_incompat_flags(sb) & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
2924		ret = -EUCLEAN;
2925		btrfs_err(fs_info,
2926		"invalid incompat flags, has 0x%llx valid mask 0x%llx",
2927			  btrfs_super_incompat_flags(sb),
2928			  (unsigned long long)BTRFS_FEATURE_INCOMPAT_SUPP);
2929		goto out;
2930	}
2931out:
2932	if (ret < 0)
2933		btrfs_err(fs_info,
2934		"super block corruption detected before writing it to disk");
2935	return ret;
2936}
2937
2938static int load_super_root(struct btrfs_root *root, u64 bytenr, u64 gen, int level)
2939{
2940	struct btrfs_tree_parent_check check = {
2941		.level = level,
2942		.transid = gen,
2943		.owner_root = root->root_key.objectid
2944	};
2945	int ret = 0;
2946
2947	root->node = read_tree_block(root->fs_info, bytenr, &check);
2948	if (IS_ERR(root->node)) {
2949		ret = PTR_ERR(root->node);
2950		root->node = NULL;
2951		return ret;
2952	}
2953	if (!extent_buffer_uptodate(root->node)) {
2954		free_extent_buffer(root->node);
2955		root->node = NULL;
2956		return -EIO;
2957	}
2958
2959	btrfs_set_root_node(&root->root_item, root->node);
2960	root->commit_root = btrfs_root_node(root);
2961	btrfs_set_root_refs(&root->root_item, 1);
2962	return ret;
2963}
2964
2965static int load_important_roots(struct btrfs_fs_info *fs_info)
2966{
2967	struct btrfs_super_block *sb = fs_info->super_copy;
2968	u64 gen, bytenr;
2969	int level, ret;
2970
2971	bytenr = btrfs_super_root(sb);
2972	gen = btrfs_super_generation(sb);
2973	level = btrfs_super_root_level(sb);
2974	ret = load_super_root(fs_info->tree_root, bytenr, gen, level);
2975	if (ret) {
2976		btrfs_warn(fs_info, "couldn't read tree root");
2977		return ret;
2978	}
2979	return 0;
2980}
2981
2982static int __cold init_tree_roots(struct btrfs_fs_info *fs_info)
2983{
2984	int backup_index = find_newest_super_backup(fs_info);
2985	struct btrfs_super_block *sb = fs_info->super_copy;
2986	struct btrfs_root *tree_root = fs_info->tree_root;
2987	bool handle_error = false;
2988	int ret = 0;
2989	int i;
2990
2991	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
2992		if (handle_error) {
2993			if (!IS_ERR(tree_root->node))
2994				free_extent_buffer(tree_root->node);
2995			tree_root->node = NULL;
2996
2997			if (!btrfs_test_opt(fs_info, USEBACKUPROOT))
2998				break;
2999
3000			free_root_pointers(fs_info, 0);
3001
3002			/*
3003			 * Don't use the log in recovery mode, it won't be
3004			 * valid
3005			 */
3006			btrfs_set_super_log_root(sb, 0);
3007
3008			/* We can't trust the free space cache either */
3009			btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
3010
3011			ret = read_backup_root(fs_info, i);
3012			backup_index = ret;
3013			if (ret < 0)
3014				return ret;
3015		}
3016
3017		ret = load_important_roots(fs_info);
3018		if (ret) {
3019			handle_error = true;
3020			continue;
3021		}
3022
3023		/*
3024		 * No need to hold btrfs_root::objectid_mutex since the fs
3025		 * hasn't been fully initialised and we are the only user
3026		 */
3027		ret = btrfs_init_root_free_objectid(tree_root);
3028		if (ret < 0) {
3029			handle_error = true;
3030			continue;
3031		}
3032
3033		ASSERT(tree_root->free_objectid <= BTRFS_LAST_FREE_OBJECTID);
3034
3035		ret = btrfs_read_roots(fs_info);
3036		if (ret < 0) {
3037			handle_error = true;
3038			continue;
3039		}
3040
3041		/* All successful */
3042		fs_info->generation = btrfs_header_generation(tree_root->node);
3043		fs_info->last_trans_committed = fs_info->generation;
3044		fs_info->last_reloc_trans = 0;
3045
3046		/* Always begin writing backup roots after the one being used */
3047		if (backup_index < 0) {
3048			fs_info->backup_root_index = 0;
3049		} else {
3050			fs_info->backup_root_index = backup_index + 1;
3051			fs_info->backup_root_index %= BTRFS_NUM_BACKUP_ROOTS;
3052		}
3053		break;
3054	}
3055
3056	return ret;
3057}
3058
3059void btrfs_init_fs_info(struct btrfs_fs_info *fs_info)
3060{
3061	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
3062	INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC);
3063	INIT_LIST_HEAD(&fs_info->trans_list);
3064	INIT_LIST_HEAD(&fs_info->dead_roots);
3065	INIT_LIST_HEAD(&fs_info->delayed_iputs);
3066	INIT_LIST_HEAD(&fs_info->delalloc_roots);
3067	INIT_LIST_HEAD(&fs_info->caching_block_groups);
3068	spin_lock_init(&fs_info->delalloc_root_lock);
3069	spin_lock_init(&fs_info->trans_lock);
3070	spin_lock_init(&fs_info->fs_roots_radix_lock);
3071	spin_lock_init(&fs_info->delayed_iput_lock);
3072	spin_lock_init(&fs_info->defrag_inodes_lock);
3073	spin_lock_init(&fs_info->super_lock);
3074	spin_lock_init(&fs_info->buffer_lock);
3075	spin_lock_init(&fs_info->unused_bgs_lock);
3076	spin_lock_init(&fs_info->treelog_bg_lock);
3077	spin_lock_init(&fs_info->zone_active_bgs_lock);
3078	spin_lock_init(&fs_info->relocation_bg_lock);
3079	rwlock_init(&fs_info->tree_mod_log_lock);
3080	rwlock_init(&fs_info->global_root_lock);
3081	mutex_init(&fs_info->unused_bg_unpin_mutex);
3082	mutex_init(&fs_info->reclaim_bgs_lock);
3083	mutex_init(&fs_info->reloc_mutex);
3084	mutex_init(&fs_info->delalloc_root_mutex);
3085	mutex_init(&fs_info->zoned_meta_io_lock);
3086	mutex_init(&fs_info->zoned_data_reloc_io_lock);
3087	seqlock_init(&fs_info->profiles_lock);
3088
3089	btrfs_lockdep_init_map(fs_info, btrfs_trans_num_writers);
3090	btrfs_lockdep_init_map(fs_info, btrfs_trans_num_extwriters);
3091	btrfs_lockdep_init_map(fs_info, btrfs_trans_pending_ordered);
3092	btrfs_lockdep_init_map(fs_info, btrfs_ordered_extent);
3093	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_commit_start,
3094				     BTRFS_LOCKDEP_TRANS_COMMIT_START);
3095	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_unblocked,
3096				     BTRFS_LOCKDEP_TRANS_UNBLOCKED);
3097	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_super_committed,
3098				     BTRFS_LOCKDEP_TRANS_SUPER_COMMITTED);
3099	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_completed,
3100				     BTRFS_LOCKDEP_TRANS_COMPLETED);
3101
3102	INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
3103	INIT_LIST_HEAD(&fs_info->space_info);
3104	INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
3105	INIT_LIST_HEAD(&fs_info->unused_bgs);
3106	INIT_LIST_HEAD(&fs_info->reclaim_bgs);
3107	INIT_LIST_HEAD(&fs_info->zone_active_bgs);
3108#ifdef CONFIG_BTRFS_DEBUG
3109	INIT_LIST_HEAD(&fs_info->allocated_roots);
3110	INIT_LIST_HEAD(&fs_info->allocated_ebs);
3111	spin_lock_init(&fs_info->eb_leak_lock);
3112#endif
3113	extent_map_tree_init(&fs_info->mapping_tree);
 
3114	btrfs_init_block_rsv(&fs_info->global_block_rsv,
3115			     BTRFS_BLOCK_RSV_GLOBAL);
3116	btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
3117	btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK);
3118	btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY);
3119	btrfs_init_block_rsv(&fs_info->delayed_block_rsv,
3120			     BTRFS_BLOCK_RSV_DELOPS);
3121	btrfs_init_block_rsv(&fs_info->delayed_refs_rsv,
3122			     BTRFS_BLOCK_RSV_DELREFS);
3123
3124	atomic_set(&fs_info->async_delalloc_pages, 0);
3125	atomic_set(&fs_info->defrag_running, 0);
3126	atomic_set(&fs_info->nr_delayed_iputs, 0);
3127	atomic64_set(&fs_info->tree_mod_seq, 0);
3128	fs_info->global_root_tree = RB_ROOT;
3129	fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE;
3130	fs_info->metadata_ratio = 0;
3131	fs_info->defrag_inodes = RB_ROOT;
3132	atomic64_set(&fs_info->free_chunk_space, 0);
3133	fs_info->tree_mod_log = RB_ROOT;
3134	fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
3135	fs_info->avg_delayed_ref_runtime = NSEC_PER_SEC >> 6; /* div by 64 */
3136	btrfs_init_ref_verify(fs_info);
3137
3138	fs_info->thread_pool_size = min_t(unsigned long,
3139					  num_online_cpus() + 2, 8);
3140
3141	INIT_LIST_HEAD(&fs_info->ordered_roots);
3142	spin_lock_init(&fs_info->ordered_root_lock);
3143
3144	btrfs_init_scrub(fs_info);
3145#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3146	fs_info->check_integrity_print_mask = 0;
3147#endif
3148	btrfs_init_balance(fs_info);
3149	btrfs_init_async_reclaim_work(fs_info);
3150
3151	rwlock_init(&fs_info->block_group_cache_lock);
3152	fs_info->block_group_cache_tree = RB_ROOT_CACHED;
3153
3154	extent_io_tree_init(fs_info, &fs_info->excluded_extents,
3155			    IO_TREE_FS_EXCLUDED_EXTENTS);
3156
3157	mutex_init(&fs_info->ordered_operations_mutex);
3158	mutex_init(&fs_info->tree_log_mutex);
3159	mutex_init(&fs_info->chunk_mutex);
3160	mutex_init(&fs_info->transaction_kthread_mutex);
3161	mutex_init(&fs_info->cleaner_mutex);
3162	mutex_init(&fs_info->ro_block_group_mutex);
3163	init_rwsem(&fs_info->commit_root_sem);
3164	init_rwsem(&fs_info->cleanup_work_sem);
3165	init_rwsem(&fs_info->subvol_sem);
3166	sema_init(&fs_info->uuid_tree_rescan_sem, 1);
3167
3168	btrfs_init_dev_replace_locks(fs_info);
3169	btrfs_init_qgroup(fs_info);
3170	btrfs_discard_init(fs_info);
3171
3172	btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
3173	btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
3174
3175	init_waitqueue_head(&fs_info->transaction_throttle);
3176	init_waitqueue_head(&fs_info->transaction_wait);
3177	init_waitqueue_head(&fs_info->transaction_blocked_wait);
3178	init_waitqueue_head(&fs_info->async_submit_wait);
3179	init_waitqueue_head(&fs_info->delayed_iputs_wait);
3180
3181	/* Usable values until the real ones are cached from the superblock */
3182	fs_info->nodesize = 4096;
3183	fs_info->sectorsize = 4096;
3184	fs_info->sectorsize_bits = ilog2(4096);
3185	fs_info->stripesize = 4096;
3186
 
 
 
3187	fs_info->max_extent_size = BTRFS_MAX_EXTENT_SIZE;
3188
3189	spin_lock_init(&fs_info->swapfile_pins_lock);
3190	fs_info->swapfile_pins = RB_ROOT;
3191
3192	fs_info->bg_reclaim_threshold = BTRFS_DEFAULT_RECLAIM_THRESH;
3193	INIT_WORK(&fs_info->reclaim_bgs_work, btrfs_reclaim_bgs_work);
3194}
3195
3196static int init_mount_fs_info(struct btrfs_fs_info *fs_info, struct super_block *sb)
3197{
3198	int ret;
3199
3200	fs_info->sb = sb;
3201	sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE;
3202	sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE);
3203
3204	ret = percpu_counter_init(&fs_info->ordered_bytes, 0, GFP_KERNEL);
3205	if (ret)
3206		return ret;
3207
3208	ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0, GFP_KERNEL);
3209	if (ret)
3210		return ret;
3211
3212	fs_info->dirty_metadata_batch = PAGE_SIZE *
3213					(1 + ilog2(nr_cpu_ids));
3214
3215	ret = percpu_counter_init(&fs_info->delalloc_bytes, 0, GFP_KERNEL);
3216	if (ret)
3217		return ret;
3218
3219	ret = percpu_counter_init(&fs_info->dev_replace.bio_counter, 0,
3220			GFP_KERNEL);
3221	if (ret)
3222		return ret;
3223
3224	fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
3225					GFP_KERNEL);
3226	if (!fs_info->delayed_root)
3227		return -ENOMEM;
3228	btrfs_init_delayed_root(fs_info->delayed_root);
3229
3230	if (sb_rdonly(sb))
3231		set_bit(BTRFS_FS_STATE_RO, &fs_info->fs_state);
3232
3233	return btrfs_alloc_stripe_hash_table(fs_info);
3234}
3235
3236static int btrfs_uuid_rescan_kthread(void *data)
3237{
3238	struct btrfs_fs_info *fs_info = data;
3239	int ret;
3240
3241	/*
3242	 * 1st step is to iterate through the existing UUID tree and
3243	 * to delete all entries that contain outdated data.
3244	 * 2nd step is to add all missing entries to the UUID tree.
3245	 */
3246	ret = btrfs_uuid_tree_iterate(fs_info);
3247	if (ret < 0) {
3248		if (ret != -EINTR)
3249			btrfs_warn(fs_info, "iterating uuid_tree failed %d",
3250				   ret);
3251		up(&fs_info->uuid_tree_rescan_sem);
3252		return ret;
3253	}
3254	return btrfs_uuid_scan_kthread(data);
3255}
3256
3257static int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
3258{
3259	struct task_struct *task;
3260
3261	down(&fs_info->uuid_tree_rescan_sem);
3262	task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
3263	if (IS_ERR(task)) {
3264		/* fs_info->update_uuid_tree_gen remains 0 in all error case */
3265		btrfs_warn(fs_info, "failed to start uuid_rescan task");
3266		up(&fs_info->uuid_tree_rescan_sem);
3267		return PTR_ERR(task);
3268	}
3269
3270	return 0;
3271}
3272
3273/*
3274 * Some options only have meaning at mount time and shouldn't persist across
3275 * remounts, or be displayed. Clear these at the end of mount and remount
3276 * code paths.
3277 */
3278void btrfs_clear_oneshot_options(struct btrfs_fs_info *fs_info)
3279{
3280	btrfs_clear_opt(fs_info->mount_opt, USEBACKUPROOT);
3281	btrfs_clear_opt(fs_info->mount_opt, CLEAR_CACHE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3282}
3283
3284/*
3285 * Mounting logic specific to read-write file systems. Shared by open_ctree
3286 * and btrfs_remount when remounting from read-only to read-write.
3287 */
3288int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info)
3289{
3290	int ret;
3291	const bool cache_opt = btrfs_test_opt(fs_info, SPACE_CACHE);
3292	bool clear_free_space_tree = false;
3293
3294	if (btrfs_test_opt(fs_info, CLEAR_CACHE) &&
3295	    btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3296		clear_free_space_tree = true;
 
 
 
 
3297	} else if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
3298		   !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID)) {
3299		btrfs_warn(fs_info, "free space tree is invalid");
3300		clear_free_space_tree = true;
3301	}
3302
3303	if (clear_free_space_tree) {
3304		btrfs_info(fs_info, "clearing free space tree");
3305		ret = btrfs_clear_free_space_tree(fs_info);
3306		if (ret) {
3307			btrfs_warn(fs_info,
3308				   "failed to clear free space tree: %d", ret);
 
 
 
 
 
 
 
 
 
 
 
3309			goto out;
3310		}
3311	}
3312
3313	/*
3314	 * btrfs_find_orphan_roots() is responsible for finding all the dead
3315	 * roots (with 0 refs), flag them with BTRFS_ROOT_DEAD_TREE and load
3316	 * them into the fs_info->fs_roots_radix tree. This must be done before
3317	 * calling btrfs_orphan_cleanup() on the tree root. If we don't do it
3318	 * first, then btrfs_orphan_cleanup() will delete a dead root's orphan
3319	 * item before the root's tree is deleted - this means that if we unmount
3320	 * or crash before the deletion completes, on the next mount we will not
3321	 * delete what remains of the tree because the orphan item does not
3322	 * exists anymore, which is what tells us we have a pending deletion.
3323	 */
3324	ret = btrfs_find_orphan_roots(fs_info);
3325	if (ret)
3326		goto out;
3327
3328	ret = btrfs_cleanup_fs_roots(fs_info);
3329	if (ret)
3330		goto out;
3331
3332	down_read(&fs_info->cleanup_work_sem);
3333	if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) ||
3334	    (ret = btrfs_orphan_cleanup(fs_info->tree_root))) {
3335		up_read(&fs_info->cleanup_work_sem);
3336		goto out;
3337	}
3338	up_read(&fs_info->cleanup_work_sem);
3339
3340	mutex_lock(&fs_info->cleaner_mutex);
3341	ret = btrfs_recover_relocation(fs_info);
3342	mutex_unlock(&fs_info->cleaner_mutex);
3343	if (ret < 0) {
3344		btrfs_warn(fs_info, "failed to recover relocation: %d", ret);
3345		goto out;
3346	}
3347
3348	if (btrfs_test_opt(fs_info, FREE_SPACE_TREE) &&
3349	    !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3350		btrfs_info(fs_info, "creating free space tree");
3351		ret = btrfs_create_free_space_tree(fs_info);
3352		if (ret) {
3353			btrfs_warn(fs_info,
3354				"failed to create free space tree: %d", ret);
3355			goto out;
3356		}
3357	}
3358
3359	if (cache_opt != btrfs_free_space_cache_v1_active(fs_info)) {
3360		ret = btrfs_set_free_space_cache_v1_active(fs_info, cache_opt);
3361		if (ret)
3362			goto out;
3363	}
3364
3365	ret = btrfs_resume_balance_async(fs_info);
3366	if (ret)
3367		goto out;
3368
3369	ret = btrfs_resume_dev_replace_async(fs_info);
3370	if (ret) {
3371		btrfs_warn(fs_info, "failed to resume dev_replace");
3372		goto out;
3373	}
3374
3375	btrfs_qgroup_rescan_resume(fs_info);
3376
3377	if (!fs_info->uuid_root) {
3378		btrfs_info(fs_info, "creating UUID tree");
3379		ret = btrfs_create_uuid_tree(fs_info);
3380		if (ret) {
3381			btrfs_warn(fs_info,
3382				   "failed to create the UUID tree %d", ret);
3383			goto out;
3384		}
3385	}
3386
3387out:
3388	return ret;
3389}
3390
3391/*
3392 * Do various sanity and dependency checks of different features.
3393 *
3394 * @is_rw_mount:	If the mount is read-write.
3395 *
3396 * This is the place for less strict checks (like for subpage or artificial
3397 * feature dependencies).
3398 *
3399 * For strict checks or possible corruption detection, see
3400 * btrfs_validate_super().
3401 *
3402 * This should be called after btrfs_parse_options(), as some mount options
3403 * (space cache related) can modify on-disk format like free space tree and
3404 * screw up certain feature dependencies.
3405 */
3406int btrfs_check_features(struct btrfs_fs_info *fs_info, bool is_rw_mount)
3407{
3408	struct btrfs_super_block *disk_super = fs_info->super_copy;
3409	u64 incompat = btrfs_super_incompat_flags(disk_super);
3410	const u64 compat_ro = btrfs_super_compat_ro_flags(disk_super);
3411	const u64 compat_ro_unsupp = (compat_ro & ~BTRFS_FEATURE_COMPAT_RO_SUPP);
3412
3413	if (incompat & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
3414		btrfs_err(fs_info,
3415		"cannot mount because of unknown incompat features (0x%llx)",
3416		    incompat);
3417		return -EINVAL;
3418	}
3419
3420	/* Runtime limitation for mixed block groups. */
3421	if ((incompat & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
3422	    (fs_info->sectorsize != fs_info->nodesize)) {
3423		btrfs_err(fs_info,
3424"unequal nodesize/sectorsize (%u != %u) are not allowed for mixed block groups",
3425			fs_info->nodesize, fs_info->sectorsize);
3426		return -EINVAL;
3427	}
3428
3429	/* Mixed backref is an always-enabled feature. */
3430	incompat |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
3431
3432	/* Set compression related flags just in case. */
3433	if (fs_info->compress_type == BTRFS_COMPRESS_LZO)
3434		incompat |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
3435	else if (fs_info->compress_type == BTRFS_COMPRESS_ZSTD)
3436		incompat |= BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD;
3437
3438	/*
3439	 * An ancient flag, which should really be marked deprecated.
3440	 * Such runtime limitation doesn't really need a incompat flag.
3441	 */
3442	if (btrfs_super_nodesize(disk_super) > PAGE_SIZE)
3443		incompat |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
3444
3445	if (compat_ro_unsupp && is_rw_mount) {
3446		btrfs_err(fs_info,
3447	"cannot mount read-write because of unknown compat_ro features (0x%llx)",
3448		       compat_ro);
3449		return -EINVAL;
3450	}
3451
3452	/*
3453	 * We have unsupported RO compat features, although RO mounted, we
3454	 * should not cause any metadata writes, including log replay.
3455	 * Or we could screw up whatever the new feature requires.
3456	 */
3457	if (compat_ro_unsupp && btrfs_super_log_root(disk_super) &&
3458	    !btrfs_test_opt(fs_info, NOLOGREPLAY)) {
3459		btrfs_err(fs_info,
3460"cannot replay dirty log with unsupported compat_ro features (0x%llx), try rescue=nologreplay",
3461			  compat_ro);
3462		return -EINVAL;
3463	}
3464
3465	/*
3466	 * Artificial limitations for block group tree, to force
3467	 * block-group-tree to rely on no-holes and free-space-tree.
3468	 */
3469	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE) &&
3470	    (!btrfs_fs_incompat(fs_info, NO_HOLES) ||
3471	     !btrfs_test_opt(fs_info, FREE_SPACE_TREE))) {
3472		btrfs_err(fs_info,
3473"block-group-tree feature requires no-holes and free-space-tree features");
3474		return -EINVAL;
3475	}
3476
3477	/*
3478	 * Subpage runtime limitation on v1 cache.
3479	 *
3480	 * V1 space cache still has some hard codeed PAGE_SIZE usage, while
3481	 * we're already defaulting to v2 cache, no need to bother v1 as it's
3482	 * going to be deprecated anyway.
3483	 */
3484	if (fs_info->sectorsize < PAGE_SIZE && btrfs_test_opt(fs_info, SPACE_CACHE)) {
3485		btrfs_warn(fs_info,
3486	"v1 space cache is not supported for page size %lu with sectorsize %u",
3487			   PAGE_SIZE, fs_info->sectorsize);
3488		return -EINVAL;
3489	}
3490
3491	/* This can be called by remount, we need to protect the super block. */
3492	spin_lock(&fs_info->super_lock);
3493	btrfs_set_super_incompat_flags(disk_super, incompat);
3494	spin_unlock(&fs_info->super_lock);
3495
3496	return 0;
3497}
3498
3499int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_devices,
3500		      char *options)
3501{
3502	u32 sectorsize;
3503	u32 nodesize;
3504	u32 stripesize;
3505	u64 generation;
3506	u64 features;
3507	u16 csum_type;
3508	struct btrfs_super_block *disk_super;
3509	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
3510	struct btrfs_root *tree_root;
3511	struct btrfs_root *chunk_root;
3512	int ret;
3513	int err = -EINVAL;
3514	int level;
3515
3516	ret = init_mount_fs_info(fs_info, sb);
3517	if (ret) {
3518		err = ret;
3519		goto fail;
3520	}
3521
3522	/* These need to be init'ed before we start creating inodes and such. */
3523	tree_root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID,
3524				     GFP_KERNEL);
3525	fs_info->tree_root = tree_root;
3526	chunk_root = btrfs_alloc_root(fs_info, BTRFS_CHUNK_TREE_OBJECTID,
3527				      GFP_KERNEL);
3528	fs_info->chunk_root = chunk_root;
3529	if (!tree_root || !chunk_root) {
3530		err = -ENOMEM;
3531		goto fail;
3532	}
3533
3534	fs_info->btree_inode = new_inode(sb);
3535	if (!fs_info->btree_inode) {
3536		err = -ENOMEM;
3537		goto fail;
3538	}
3539	mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
3540	btrfs_init_btree_inode(fs_info);
3541
3542	invalidate_bdev(fs_devices->latest_dev->bdev);
3543
3544	/*
3545	 * Read super block and check the signature bytes only
3546	 */
3547	disk_super = btrfs_read_dev_super(fs_devices->latest_dev->bdev);
3548	if (IS_ERR(disk_super)) {
3549		err = PTR_ERR(disk_super);
3550		goto fail_alloc;
3551	}
3552
 
3553	/*
3554	 * Verify the type first, if that or the checksum value are
3555	 * corrupted, we'll find out
3556	 */
3557	csum_type = btrfs_super_csum_type(disk_super);
3558	if (!btrfs_supported_super_csum(csum_type)) {
3559		btrfs_err(fs_info, "unsupported checksum algorithm: %u",
3560			  csum_type);
3561		err = -EINVAL;
3562		btrfs_release_disk_super(disk_super);
3563		goto fail_alloc;
3564	}
3565
3566	fs_info->csum_size = btrfs_super_csum_size(disk_super);
3567
3568	ret = btrfs_init_csum_hash(fs_info, csum_type);
3569	if (ret) {
3570		err = ret;
3571		btrfs_release_disk_super(disk_super);
3572		goto fail_alloc;
3573	}
3574
3575	/*
3576	 * We want to check superblock checksum, the type is stored inside.
3577	 * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k).
3578	 */
3579	if (btrfs_check_super_csum(fs_info, disk_super)) {
3580		btrfs_err(fs_info, "superblock checksum mismatch");
3581		err = -EINVAL;
3582		btrfs_release_disk_super(disk_super);
3583		goto fail_alloc;
3584	}
3585
3586	/*
3587	 * super_copy is zeroed at allocation time and we never touch the
3588	 * following bytes up to INFO_SIZE, the checksum is calculated from
3589	 * the whole block of INFO_SIZE
3590	 */
3591	memcpy(fs_info->super_copy, disk_super, sizeof(*fs_info->super_copy));
3592	btrfs_release_disk_super(disk_super);
3593
3594	disk_super = fs_info->super_copy;
3595
3596
3597	features = btrfs_super_flags(disk_super);
3598	if (features & BTRFS_SUPER_FLAG_CHANGING_FSID_V2) {
3599		features &= ~BTRFS_SUPER_FLAG_CHANGING_FSID_V2;
3600		btrfs_set_super_flags(disk_super, features);
3601		btrfs_info(fs_info,
3602			"found metadata UUID change in progress flag, clearing");
3603	}
3604
3605	memcpy(fs_info->super_for_commit, fs_info->super_copy,
3606	       sizeof(*fs_info->super_for_commit));
3607
3608	ret = btrfs_validate_mount_super(fs_info);
3609	if (ret) {
3610		btrfs_err(fs_info, "superblock contains fatal errors");
3611		err = -EINVAL;
3612		goto fail_alloc;
3613	}
3614
3615	if (!btrfs_super_root(disk_super))
 
 
3616		goto fail_alloc;
 
3617
3618	/* check FS state, whether FS is broken. */
3619	if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
3620		set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state);
3621
3622	/*
3623	 * In the long term, we'll store the compression type in the super
3624	 * block, and it'll be used for per file compression control.
3625	 */
3626	fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
3627
3628
3629	/* Set up fs_info before parsing mount options */
3630	nodesize = btrfs_super_nodesize(disk_super);
3631	sectorsize = btrfs_super_sectorsize(disk_super);
3632	stripesize = sectorsize;
3633	fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids));
3634	fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
3635
3636	fs_info->nodesize = nodesize;
3637	fs_info->sectorsize = sectorsize;
3638	fs_info->sectorsize_bits = ilog2(sectorsize);
3639	fs_info->csums_per_leaf = BTRFS_MAX_ITEM_SIZE(fs_info) / fs_info->csum_size;
3640	fs_info->stripesize = stripesize;
3641
3642	ret = btrfs_parse_options(fs_info, options, sb->s_flags);
3643	if (ret) {
3644		err = ret;
 
 
 
 
 
3645		goto fail_alloc;
3646	}
3647
3648	ret = btrfs_check_features(fs_info, !sb_rdonly(sb));
3649	if (ret < 0) {
3650		err = ret;
3651		goto fail_alloc;
3652	}
 
 
 
 
 
3653
3654	if (sectorsize < PAGE_SIZE) {
3655		struct btrfs_subpage_info *subpage_info;
3656
3657		/*
3658		 * V1 space cache has some hardcoded PAGE_SIZE usage, and is
3659		 * going to be deprecated.
3660		 *
3661		 * Force to use v2 cache for subpage case.
3662		 */
3663		btrfs_clear_opt(fs_info->mount_opt, SPACE_CACHE);
3664		btrfs_set_and_info(fs_info, FREE_SPACE_TREE,
3665			"forcing free space tree for sector size %u with page size %lu",
3666			sectorsize, PAGE_SIZE);
3667
3668		btrfs_warn(fs_info,
3669		"read-write for sector size %u with page size %lu is experimental",
3670			   sectorsize, PAGE_SIZE);
3671		subpage_info = kzalloc(sizeof(*subpage_info), GFP_KERNEL);
3672		if (!subpage_info)
 
3673			goto fail_alloc;
 
3674		btrfs_init_subpage_info(subpage_info, sectorsize);
3675		fs_info->subpage_info = subpage_info;
3676	}
3677
3678	ret = btrfs_init_workqueues(fs_info);
3679	if (ret) {
3680		err = ret;
3681		goto fail_sb_buffer;
3682	}
3683
3684	sb->s_bdi->ra_pages *= btrfs_super_num_devices(disk_super);
3685	sb->s_bdi->ra_pages = max(sb->s_bdi->ra_pages, SZ_4M / PAGE_SIZE);
3686
3687	sb->s_blocksize = sectorsize;
3688	sb->s_blocksize_bits = blksize_bits(sectorsize);
3689	memcpy(&sb->s_uuid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE);
3690
3691	mutex_lock(&fs_info->chunk_mutex);
3692	ret = btrfs_read_sys_array(fs_info);
3693	mutex_unlock(&fs_info->chunk_mutex);
3694	if (ret) {
3695		btrfs_err(fs_info, "failed to read the system array: %d", ret);
3696		goto fail_sb_buffer;
3697	}
3698
3699	generation = btrfs_super_chunk_root_generation(disk_super);
3700	level = btrfs_super_chunk_root_level(disk_super);
3701	ret = load_super_root(chunk_root, btrfs_super_chunk_root(disk_super),
3702			      generation, level);
3703	if (ret) {
3704		btrfs_err(fs_info, "failed to read chunk root");
3705		goto fail_tree_roots;
3706	}
3707
3708	read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
3709			   offsetof(struct btrfs_header, chunk_tree_uuid),
3710			   BTRFS_UUID_SIZE);
3711
3712	ret = btrfs_read_chunk_tree(fs_info);
3713	if (ret) {
3714		btrfs_err(fs_info, "failed to read chunk tree: %d", ret);
3715		goto fail_tree_roots;
3716	}
3717
3718	/*
3719	 * At this point we know all the devices that make this filesystem,
3720	 * including the seed devices but we don't know yet if the replace
3721	 * target is required. So free devices that are not part of this
3722	 * filesystem but skip the replace target device which is checked
3723	 * below in btrfs_init_dev_replace().
3724	 */
3725	btrfs_free_extra_devids(fs_devices);
3726	if (!fs_devices->latest_dev->bdev) {
3727		btrfs_err(fs_info, "failed to read devices");
 
3728		goto fail_tree_roots;
3729	}
3730
3731	ret = init_tree_roots(fs_info);
3732	if (ret)
3733		goto fail_tree_roots;
3734
3735	/*
3736	 * Get zone type information of zoned block devices. This will also
3737	 * handle emulation of a zoned filesystem if a regular device has the
3738	 * zoned incompat feature flag set.
3739	 */
3740	ret = btrfs_get_dev_zone_info_all_devices(fs_info);
3741	if (ret) {
3742		btrfs_err(fs_info,
3743			  "zoned: failed to read device zone info: %d",
3744			  ret);
3745		goto fail_block_groups;
3746	}
3747
3748	/*
3749	 * If we have a uuid root and we're not being told to rescan we need to
3750	 * check the generation here so we can set the
3751	 * BTRFS_FS_UPDATE_UUID_TREE_GEN bit.  Otherwise we could commit the
3752	 * transaction during a balance or the log replay without updating the
3753	 * uuid generation, and then if we crash we would rescan the uuid tree,
3754	 * even though it was perfectly fine.
3755	 */
3756	if (fs_info->uuid_root && !btrfs_test_opt(fs_info, RESCAN_UUID_TREE) &&
3757	    fs_info->generation == btrfs_super_uuid_tree_generation(disk_super))
3758		set_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags);
3759
3760	ret = btrfs_verify_dev_extents(fs_info);
3761	if (ret) {
3762		btrfs_err(fs_info,
3763			  "failed to verify dev extents against chunks: %d",
3764			  ret);
3765		goto fail_block_groups;
3766	}
3767	ret = btrfs_recover_balance(fs_info);
3768	if (ret) {
3769		btrfs_err(fs_info, "failed to recover balance: %d", ret);
3770		goto fail_block_groups;
3771	}
3772
3773	ret = btrfs_init_dev_stats(fs_info);
3774	if (ret) {
3775		btrfs_err(fs_info, "failed to init dev_stats: %d", ret);
3776		goto fail_block_groups;
3777	}
3778
3779	ret = btrfs_init_dev_replace(fs_info);
3780	if (ret) {
3781		btrfs_err(fs_info, "failed to init dev_replace: %d", ret);
3782		goto fail_block_groups;
3783	}
3784
3785	ret = btrfs_check_zoned_mode(fs_info);
3786	if (ret) {
3787		btrfs_err(fs_info, "failed to initialize zoned mode: %d",
3788			  ret);
3789		goto fail_block_groups;
3790	}
3791
3792	ret = btrfs_sysfs_add_fsid(fs_devices);
3793	if (ret) {
3794		btrfs_err(fs_info, "failed to init sysfs fsid interface: %d",
3795				ret);
3796		goto fail_block_groups;
3797	}
3798
3799	ret = btrfs_sysfs_add_mounted(fs_info);
3800	if (ret) {
3801		btrfs_err(fs_info, "failed to init sysfs interface: %d", ret);
3802		goto fail_fsdev_sysfs;
3803	}
3804
3805	ret = btrfs_init_space_info(fs_info);
3806	if (ret) {
3807		btrfs_err(fs_info, "failed to initialize space info: %d", ret);
3808		goto fail_sysfs;
3809	}
3810
3811	ret = btrfs_read_block_groups(fs_info);
3812	if (ret) {
3813		btrfs_err(fs_info, "failed to read block groups: %d", ret);
3814		goto fail_sysfs;
3815	}
3816
3817	btrfs_free_zone_cache(fs_info);
3818
 
 
3819	if (!sb_rdonly(sb) && fs_info->fs_devices->missing_devices &&
3820	    !btrfs_check_rw_degradable(fs_info, NULL)) {
3821		btrfs_warn(fs_info,
3822		"writable mount is not allowed due to too many missing devices");
 
3823		goto fail_sysfs;
3824	}
3825
3826	fs_info->cleaner_kthread = kthread_run(cleaner_kthread, fs_info,
3827					       "btrfs-cleaner");
3828	if (IS_ERR(fs_info->cleaner_kthread))
 
3829		goto fail_sysfs;
 
3830
3831	fs_info->transaction_kthread = kthread_run(transaction_kthread,
3832						   tree_root,
3833						   "btrfs-transaction");
3834	if (IS_ERR(fs_info->transaction_kthread))
 
3835		goto fail_cleaner;
3836
3837	if (!btrfs_test_opt(fs_info, NOSSD) &&
3838	    !fs_info->fs_devices->rotating) {
3839		btrfs_set_and_info(fs_info, SSD, "enabling ssd optimizations");
3840	}
3841
3842	/*
3843	 * For devices supporting discard turn on discard=async automatically,
3844	 * unless it's already set or disabled. This could be turned off by
3845	 * nodiscard for the same mount.
3846	 */
3847	if (!(btrfs_test_opt(fs_info, DISCARD_SYNC) ||
3848	      btrfs_test_opt(fs_info, DISCARD_ASYNC) ||
3849	      btrfs_test_opt(fs_info, NODISCARD)) &&
3850	    fs_info->fs_devices->discardable) {
3851		btrfs_set_and_info(fs_info, DISCARD_ASYNC,
3852				   "auto enabling async discard");
3853		btrfs_clear_opt(fs_info->mount_opt, NODISCARD);
3854	}
3855
3856#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3857	if (btrfs_test_opt(fs_info, CHECK_INTEGRITY)) {
3858		ret = btrfsic_mount(fs_info, fs_devices,
3859				    btrfs_test_opt(fs_info,
3860					CHECK_INTEGRITY_DATA) ? 1 : 0,
3861				    fs_info->check_integrity_print_mask);
3862		if (ret)
3863			btrfs_warn(fs_info,
3864				"failed to initialize integrity check module: %d",
3865				ret);
3866	}
3867#endif
3868	ret = btrfs_read_qgroup_config(fs_info);
3869	if (ret)
3870		goto fail_trans_kthread;
3871
3872	if (btrfs_build_ref_tree(fs_info))
3873		btrfs_err(fs_info, "couldn't build ref tree");
3874
3875	/* do not make disk changes in broken FS or nologreplay is given */
3876	if (btrfs_super_log_root(disk_super) != 0 &&
3877	    !btrfs_test_opt(fs_info, NOLOGREPLAY)) {
3878		btrfs_info(fs_info, "start tree-log replay");
3879		ret = btrfs_replay_log(fs_info, fs_devices);
3880		if (ret) {
3881			err = ret;
3882			goto fail_qgroup;
3883		}
3884	}
3885
3886	fs_info->fs_root = btrfs_get_fs_root(fs_info, BTRFS_FS_TREE_OBJECTID, true);
3887	if (IS_ERR(fs_info->fs_root)) {
3888		err = PTR_ERR(fs_info->fs_root);
3889		btrfs_warn(fs_info, "failed to read fs tree: %d", err);
3890		fs_info->fs_root = NULL;
3891		goto fail_qgroup;
3892	}
3893
3894	if (sb_rdonly(sb))
3895		goto clear_oneshot;
3896
3897	ret = btrfs_start_pre_rw_mount(fs_info);
3898	if (ret) {
3899		close_ctree(fs_info);
3900		return ret;
3901	}
3902	btrfs_discard_resume(fs_info);
3903
3904	if (fs_info->uuid_root &&
3905	    (btrfs_test_opt(fs_info, RESCAN_UUID_TREE) ||
3906	     fs_info->generation != btrfs_super_uuid_tree_generation(disk_super))) {
3907		btrfs_info(fs_info, "checking UUID tree");
3908		ret = btrfs_check_uuid_tree(fs_info);
3909		if (ret) {
3910			btrfs_warn(fs_info,
3911				"failed to check the UUID tree: %d", ret);
3912			close_ctree(fs_info);
3913			return ret;
3914		}
3915	}
3916
3917	set_bit(BTRFS_FS_OPEN, &fs_info->flags);
3918
3919	/* Kick the cleaner thread so it'll start deleting snapshots. */
3920	if (test_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags))
3921		wake_up_process(fs_info->cleaner_kthread);
3922
3923clear_oneshot:
3924	btrfs_clear_oneshot_options(fs_info);
3925	return 0;
3926
3927fail_qgroup:
3928	btrfs_free_qgroup_config(fs_info);
3929fail_trans_kthread:
3930	kthread_stop(fs_info->transaction_kthread);
3931	btrfs_cleanup_transaction(fs_info);
3932	btrfs_free_fs_roots(fs_info);
3933fail_cleaner:
3934	kthread_stop(fs_info->cleaner_kthread);
3935
3936	/*
3937	 * make sure we're done with the btree inode before we stop our
3938	 * kthreads
3939	 */
3940	filemap_write_and_wait(fs_info->btree_inode->i_mapping);
3941
3942fail_sysfs:
3943	btrfs_sysfs_remove_mounted(fs_info);
3944
3945fail_fsdev_sysfs:
3946	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
3947
3948fail_block_groups:
3949	btrfs_put_block_group_cache(fs_info);
3950
3951fail_tree_roots:
3952	if (fs_info->data_reloc_root)
3953		btrfs_drop_and_free_fs_root(fs_info, fs_info->data_reloc_root);
3954	free_root_pointers(fs_info, true);
3955	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
3956
3957fail_sb_buffer:
3958	btrfs_stop_all_workers(fs_info);
3959	btrfs_free_block_groups(fs_info);
3960fail_alloc:
3961	btrfs_mapping_tree_free(&fs_info->mapping_tree);
3962
3963	iput(fs_info->btree_inode);
3964fail:
3965	btrfs_close_devices(fs_info->fs_devices);
3966	return err;
 
3967}
3968ALLOW_ERROR_INJECTION(open_ctree, ERRNO);
3969
3970static void btrfs_end_super_write(struct bio *bio)
3971{
3972	struct btrfs_device *device = bio->bi_private;
3973	struct bio_vec *bvec;
3974	struct bvec_iter_all iter_all;
3975	struct page *page;
3976
3977	bio_for_each_segment_all(bvec, bio, iter_all) {
3978		page = bvec->bv_page;
3979
3980		if (bio->bi_status) {
3981			btrfs_warn_rl_in_rcu(device->fs_info,
3982				"lost page write due to IO error on %s (%d)",
3983				btrfs_dev_name(device),
3984				blk_status_to_errno(bio->bi_status));
3985			ClearPageUptodate(page);
3986			SetPageError(page);
3987			btrfs_dev_stat_inc_and_print(device,
3988						     BTRFS_DEV_STAT_WRITE_ERRS);
3989		} else {
3990			SetPageUptodate(page);
3991		}
3992
3993		put_page(page);
3994		unlock_page(page);
3995	}
3996
3997	bio_put(bio);
3998}
3999
4000struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
4001						   int copy_num, bool drop_cache)
4002{
4003	struct btrfs_super_block *super;
4004	struct page *page;
4005	u64 bytenr, bytenr_orig;
4006	struct address_space *mapping = bdev->bd_inode->i_mapping;
4007	int ret;
4008
4009	bytenr_orig = btrfs_sb_offset(copy_num);
4010	ret = btrfs_sb_log_location_bdev(bdev, copy_num, READ, &bytenr);
4011	if (ret == -ENOENT)
4012		return ERR_PTR(-EINVAL);
4013	else if (ret)
4014		return ERR_PTR(ret);
4015
4016	if (bytenr + BTRFS_SUPER_INFO_SIZE >= bdev_nr_bytes(bdev))
4017		return ERR_PTR(-EINVAL);
4018
4019	if (drop_cache) {
4020		/* This should only be called with the primary sb. */
4021		ASSERT(copy_num == 0);
4022
4023		/*
4024		 * Drop the page of the primary superblock, so later read will
4025		 * always read from the device.
4026		 */
4027		invalidate_inode_pages2_range(mapping,
4028				bytenr >> PAGE_SHIFT,
4029				(bytenr + BTRFS_SUPER_INFO_SIZE) >> PAGE_SHIFT);
4030	}
4031
4032	page = read_cache_page_gfp(mapping, bytenr >> PAGE_SHIFT, GFP_NOFS);
4033	if (IS_ERR(page))
4034		return ERR_CAST(page);
4035
4036	super = page_address(page);
4037	if (btrfs_super_magic(super) != BTRFS_MAGIC) {
4038		btrfs_release_disk_super(super);
4039		return ERR_PTR(-ENODATA);
4040	}
4041
4042	if (btrfs_super_bytenr(super) != bytenr_orig) {
4043		btrfs_release_disk_super(super);
4044		return ERR_PTR(-EINVAL);
4045	}
4046
4047	return super;
4048}
4049
4050
4051struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev)
4052{
4053	struct btrfs_super_block *super, *latest = NULL;
4054	int i;
4055	u64 transid = 0;
4056
4057	/* we would like to check all the supers, but that would make
4058	 * a btrfs mount succeed after a mkfs from a different FS.
4059	 * So, we need to add a special mount option to scan for
4060	 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
4061	 */
4062	for (i = 0; i < 1; i++) {
4063		super = btrfs_read_dev_one_super(bdev, i, false);
4064		if (IS_ERR(super))
4065			continue;
4066
4067		if (!latest || btrfs_super_generation(super) > transid) {
4068			if (latest)
4069				btrfs_release_disk_super(super);
4070
4071			latest = super;
4072			transid = btrfs_super_generation(super);
4073		}
4074	}
4075
4076	return super;
4077}
4078
4079/*
4080 * Write superblock @sb to the @device. Do not wait for completion, all the
4081 * pages we use for writing are locked.
4082 *
4083 * Write @max_mirrors copies of the superblock, where 0 means default that fit
4084 * the expected device size at commit time. Note that max_mirrors must be
4085 * same for write and wait phases.
4086 *
4087 * Return number of errors when page is not found or submission fails.
4088 */
4089static int write_dev_supers(struct btrfs_device *device,
4090			    struct btrfs_super_block *sb, int max_mirrors)
4091{
4092	struct btrfs_fs_info *fs_info = device->fs_info;
4093	struct address_space *mapping = device->bdev->bd_inode->i_mapping;
4094	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
4095	int i;
4096	int errors = 0;
4097	int ret;
4098	u64 bytenr, bytenr_orig;
4099
4100	if (max_mirrors == 0)
4101		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
4102
4103	shash->tfm = fs_info->csum_shash;
4104
4105	for (i = 0; i < max_mirrors; i++) {
4106		struct page *page;
4107		struct bio *bio;
4108		struct btrfs_super_block *disk_super;
4109
4110		bytenr_orig = btrfs_sb_offset(i);
4111		ret = btrfs_sb_log_location(device, i, WRITE, &bytenr);
4112		if (ret == -ENOENT) {
4113			continue;
4114		} else if (ret < 0) {
4115			btrfs_err(device->fs_info,
4116				"couldn't get super block location for mirror %d",
4117				i);
4118			errors++;
4119			continue;
4120		}
4121		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
4122		    device->commit_total_bytes)
4123			break;
4124
4125		btrfs_set_super_bytenr(sb, bytenr_orig);
4126
4127		crypto_shash_digest(shash, (const char *)sb + BTRFS_CSUM_SIZE,
4128				    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE,
4129				    sb->csum);
4130
4131		page = find_or_create_page(mapping, bytenr >> PAGE_SHIFT,
4132					   GFP_NOFS);
4133		if (!page) {
4134			btrfs_err(device->fs_info,
4135			    "couldn't get super block page for bytenr %llu",
4136			    bytenr);
4137			errors++;
4138			continue;
4139		}
4140
4141		/* Bump the refcount for wait_dev_supers() */
4142		get_page(page);
4143
4144		disk_super = page_address(page);
4145		memcpy(disk_super, sb, BTRFS_SUPER_INFO_SIZE);
4146
4147		/*
4148		 * Directly use bios here instead of relying on the page cache
4149		 * to do I/O, so we don't lose the ability to do integrity
4150		 * checking.
4151		 */
4152		bio = bio_alloc(device->bdev, 1,
4153				REQ_OP_WRITE | REQ_SYNC | REQ_META | REQ_PRIO,
4154				GFP_NOFS);
4155		bio->bi_iter.bi_sector = bytenr >> SECTOR_SHIFT;
4156		bio->bi_private = device;
4157		bio->bi_end_io = btrfs_end_super_write;
4158		__bio_add_page(bio, page, BTRFS_SUPER_INFO_SIZE,
4159			       offset_in_page(bytenr));
4160
4161		/*
4162		 * We FUA only the first super block.  The others we allow to
4163		 * go down lazy and there's a short window where the on-disk
4164		 * copies might still contain the older version.
4165		 */
4166		if (i == 0 && !btrfs_test_opt(device->fs_info, NOBARRIER))
4167			bio->bi_opf |= REQ_FUA;
4168
4169		btrfsic_check_bio(bio);
4170		submit_bio(bio);
4171
4172		if (btrfs_advance_sb_log(device, i))
4173			errors++;
4174	}
4175	return errors < i ? 0 : -1;
4176}
4177
4178/*
4179 * Wait for write completion of superblocks done by write_dev_supers,
4180 * @max_mirrors same for write and wait phases.
4181 *
4182 * Return number of errors when page is not found or not marked up to
4183 * date.
4184 */
4185static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
4186{
4187	int i;
4188	int errors = 0;
4189	bool primary_failed = false;
4190	int ret;
4191	u64 bytenr;
4192
4193	if (max_mirrors == 0)
4194		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
4195
4196	for (i = 0; i < max_mirrors; i++) {
4197		struct page *page;
4198
4199		ret = btrfs_sb_log_location(device, i, READ, &bytenr);
4200		if (ret == -ENOENT) {
4201			break;
4202		} else if (ret < 0) {
4203			errors++;
4204			if (i == 0)
4205				primary_failed = true;
4206			continue;
4207		}
4208		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
4209		    device->commit_total_bytes)
4210			break;
4211
4212		page = find_get_page(device->bdev->bd_inode->i_mapping,
4213				     bytenr >> PAGE_SHIFT);
4214		if (!page) {
4215			errors++;
4216			if (i == 0)
4217				primary_failed = true;
4218			continue;
4219		}
4220		/* Page is submitted locked and unlocked once the IO completes */
4221		wait_on_page_locked(page);
4222		if (PageError(page)) {
4223			errors++;
4224			if (i == 0)
4225				primary_failed = true;
4226		}
4227
4228		/* Drop our reference */
4229		put_page(page);
4230
4231		/* Drop the reference from the writing run */
4232		put_page(page);
4233	}
4234
4235	/* log error, force error return */
4236	if (primary_failed) {
4237		btrfs_err(device->fs_info, "error writing primary super block to device %llu",
4238			  device->devid);
4239		return -1;
4240	}
4241
4242	return errors < i ? 0 : -1;
4243}
4244
4245/*
4246 * endio for the write_dev_flush, this will wake anyone waiting
4247 * for the barrier when it is done
4248 */
4249static void btrfs_end_empty_barrier(struct bio *bio)
4250{
4251	bio_uninit(bio);
4252	complete(bio->bi_private);
4253}
4254
4255/*
4256 * Submit a flush request to the device if it supports it. Error handling is
4257 * done in the waiting counterpart.
4258 */
4259static void write_dev_flush(struct btrfs_device *device)
4260{
4261	struct bio *bio = &device->flush_bio;
4262
4263#ifndef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4264	/*
4265	 * When a disk has write caching disabled, we skip submission of a bio
4266	 * with flush and sync requests before writing the superblock, since
4267	 * it's not needed. However when the integrity checker is enabled, this
4268	 * results in reports that there are metadata blocks referred by a
4269	 * superblock that were not properly flushed. So don't skip the bio
4270	 * submission only when the integrity checker is enabled for the sake
4271	 * of simplicity, since this is a debug tool and not meant for use in
4272	 * non-debug builds.
4273	 */
4274	if (!bdev_write_cache(device->bdev))
4275		return;
4276#endif
4277
4278	bio_init(bio, device->bdev, NULL, 0,
4279		 REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH);
4280	bio->bi_end_io = btrfs_end_empty_barrier;
4281	init_completion(&device->flush_wait);
4282	bio->bi_private = &device->flush_wait;
4283
4284	btrfsic_check_bio(bio);
4285	submit_bio(bio);
4286	set_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
4287}
4288
4289/*
4290 * If the flush bio has been submitted by write_dev_flush, wait for it.
 
4291 */
4292static blk_status_t wait_dev_flush(struct btrfs_device *device)
4293{
4294	struct bio *bio = &device->flush_bio;
4295
4296	if (!test_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state))
4297		return BLK_STS_OK;
4298
4299	clear_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
4300	wait_for_completion_io(&device->flush_wait);
4301
4302	return bio->bi_status;
4303}
 
 
 
4304
4305static int check_barrier_error(struct btrfs_fs_info *fs_info)
4306{
4307	if (!btrfs_check_rw_degradable(fs_info, NULL))
4308		return -EIO;
4309	return 0;
4310}
4311
4312/*
4313 * send an empty flush down to each device in parallel,
4314 * then wait for them
4315 */
4316static int barrier_all_devices(struct btrfs_fs_info *info)
4317{
4318	struct list_head *head;
4319	struct btrfs_device *dev;
4320	int errors_wait = 0;
4321	blk_status_t ret;
4322
4323	lockdep_assert_held(&info->fs_devices->device_list_mutex);
4324	/* send down all the barriers */
4325	head = &info->fs_devices->devices;
4326	list_for_each_entry(dev, head, dev_list) {
4327		if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
4328			continue;
4329		if (!dev->bdev)
4330			continue;
4331		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4332		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4333			continue;
4334
4335		write_dev_flush(dev);
4336		dev->last_flush_error = BLK_STS_OK;
4337	}
4338
4339	/* wait for all the barriers */
4340	list_for_each_entry(dev, head, dev_list) {
4341		if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
4342			continue;
4343		if (!dev->bdev) {
4344			errors_wait++;
4345			continue;
4346		}
4347		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4348		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4349			continue;
4350
4351		ret = wait_dev_flush(dev);
4352		if (ret) {
4353			dev->last_flush_error = ret;
4354			btrfs_dev_stat_inc_and_print(dev,
4355					BTRFS_DEV_STAT_FLUSH_ERRS);
4356			errors_wait++;
4357		}
4358	}
4359
4360	if (errors_wait) {
4361		/*
4362		 * At some point we need the status of all disks
4363		 * to arrive at the volume status. So error checking
4364		 * is being pushed to a separate loop.
4365		 */
4366		return check_barrier_error(info);
4367	}
4368	return 0;
4369}
4370
4371int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags)
4372{
4373	int raid_type;
4374	int min_tolerated = INT_MAX;
4375
4376	if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 ||
4377	    (flags & BTRFS_AVAIL_ALLOC_BIT_SINGLE))
4378		min_tolerated = min_t(int, min_tolerated,
4379				    btrfs_raid_array[BTRFS_RAID_SINGLE].
4380				    tolerated_failures);
4381
4382	for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
4383		if (raid_type == BTRFS_RAID_SINGLE)
4384			continue;
4385		if (!(flags & btrfs_raid_array[raid_type].bg_flag))
4386			continue;
4387		min_tolerated = min_t(int, min_tolerated,
4388				    btrfs_raid_array[raid_type].
4389				    tolerated_failures);
4390	}
4391
4392	if (min_tolerated == INT_MAX) {
4393		pr_warn("BTRFS: unknown raid flag: %llu", flags);
4394		min_tolerated = 0;
4395	}
4396
4397	return min_tolerated;
4398}
4399
4400int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors)
4401{
4402	struct list_head *head;
4403	struct btrfs_device *dev;
4404	struct btrfs_super_block *sb;
4405	struct btrfs_dev_item *dev_item;
4406	int ret;
4407	int do_barriers;
4408	int max_errors;
4409	int total_errors = 0;
4410	u64 flags;
4411
4412	do_barriers = !btrfs_test_opt(fs_info, NOBARRIER);
4413
4414	/*
4415	 * max_mirrors == 0 indicates we're from commit_transaction,
4416	 * not from fsync where the tree roots in fs_info have not
4417	 * been consistent on disk.
4418	 */
4419	if (max_mirrors == 0)
4420		backup_super_roots(fs_info);
4421
4422	sb = fs_info->super_for_commit;
4423	dev_item = &sb->dev_item;
4424
4425	mutex_lock(&fs_info->fs_devices->device_list_mutex);
4426	head = &fs_info->fs_devices->devices;
4427	max_errors = btrfs_super_num_devices(fs_info->super_copy) - 1;
4428
4429	if (do_barriers) {
4430		ret = barrier_all_devices(fs_info);
4431		if (ret) {
4432			mutex_unlock(
4433				&fs_info->fs_devices->device_list_mutex);
4434			btrfs_handle_fs_error(fs_info, ret,
4435					      "errors while submitting device barriers.");
4436			return ret;
4437		}
4438	}
4439
4440	list_for_each_entry(dev, head, dev_list) {
4441		if (!dev->bdev) {
4442			total_errors++;
4443			continue;
4444		}
4445		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4446		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4447			continue;
4448
4449		btrfs_set_stack_device_generation(dev_item, 0);
4450		btrfs_set_stack_device_type(dev_item, dev->type);
4451		btrfs_set_stack_device_id(dev_item, dev->devid);
4452		btrfs_set_stack_device_total_bytes(dev_item,
4453						   dev->commit_total_bytes);
4454		btrfs_set_stack_device_bytes_used(dev_item,
4455						  dev->commit_bytes_used);
4456		btrfs_set_stack_device_io_align(dev_item, dev->io_align);
4457		btrfs_set_stack_device_io_width(dev_item, dev->io_width);
4458		btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
4459		memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
4460		memcpy(dev_item->fsid, dev->fs_devices->metadata_uuid,
4461		       BTRFS_FSID_SIZE);
4462
4463		flags = btrfs_super_flags(sb);
4464		btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
4465
4466		ret = btrfs_validate_write_super(fs_info, sb);
4467		if (ret < 0) {
4468			mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4469			btrfs_handle_fs_error(fs_info, -EUCLEAN,
4470				"unexpected superblock corruption detected");
4471			return -EUCLEAN;
4472		}
4473
4474		ret = write_dev_supers(dev, sb, max_mirrors);
4475		if (ret)
4476			total_errors++;
4477	}
4478	if (total_errors > max_errors) {
4479		btrfs_err(fs_info, "%d errors while writing supers",
4480			  total_errors);
4481		mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4482
4483		/* FUA is masked off if unsupported and can't be the reason */
4484		btrfs_handle_fs_error(fs_info, -EIO,
4485				      "%d errors while writing supers",
4486				      total_errors);
4487		return -EIO;
4488	}
4489
4490	total_errors = 0;
4491	list_for_each_entry(dev, head, dev_list) {
4492		if (!dev->bdev)
4493			continue;
4494		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4495		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4496			continue;
4497
4498		ret = wait_dev_supers(dev, max_mirrors);
4499		if (ret)
4500			total_errors++;
4501	}
4502	mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4503	if (total_errors > max_errors) {
4504		btrfs_handle_fs_error(fs_info, -EIO,
4505				      "%d errors while writing supers",
4506				      total_errors);
4507		return -EIO;
4508	}
4509	return 0;
4510}
4511
4512/* Drop a fs root from the radix tree and free it. */
4513void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
4514				  struct btrfs_root *root)
4515{
4516	bool drop_ref = false;
4517
4518	spin_lock(&fs_info->fs_roots_radix_lock);
4519	radix_tree_delete(&fs_info->fs_roots_radix,
4520			  (unsigned long)root->root_key.objectid);
4521	if (test_and_clear_bit(BTRFS_ROOT_IN_RADIX, &root->state))
4522		drop_ref = true;
4523	spin_unlock(&fs_info->fs_roots_radix_lock);
4524
4525	if (BTRFS_FS_ERROR(fs_info)) {
4526		ASSERT(root->log_root == NULL);
4527		if (root->reloc_root) {
4528			btrfs_put_root(root->reloc_root);
4529			root->reloc_root = NULL;
4530		}
4531	}
4532
4533	if (drop_ref)
4534		btrfs_put_root(root);
4535}
4536
4537int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
4538{
4539	u64 root_objectid = 0;
4540	struct btrfs_root *gang[8];
4541	int i = 0;
4542	int err = 0;
4543	unsigned int ret = 0;
4544
4545	while (1) {
4546		spin_lock(&fs_info->fs_roots_radix_lock);
4547		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
4548					     (void **)gang, root_objectid,
4549					     ARRAY_SIZE(gang));
4550		if (!ret) {
4551			spin_unlock(&fs_info->fs_roots_radix_lock);
4552			break;
4553		}
4554		root_objectid = gang[ret - 1]->root_key.objectid + 1;
4555
4556		for (i = 0; i < ret; i++) {
4557			/* Avoid to grab roots in dead_roots */
4558			if (btrfs_root_refs(&gang[i]->root_item) == 0) {
4559				gang[i] = NULL;
4560				continue;
4561			}
4562			/* grab all the search result for later use */
4563			gang[i] = btrfs_grab_root(gang[i]);
4564		}
4565		spin_unlock(&fs_info->fs_roots_radix_lock);
4566
4567		for (i = 0; i < ret; i++) {
4568			if (!gang[i])
4569				continue;
4570			root_objectid = gang[i]->root_key.objectid;
4571			err = btrfs_orphan_cleanup(gang[i]);
4572			if (err)
4573				break;
4574			btrfs_put_root(gang[i]);
4575		}
4576		root_objectid++;
4577	}
4578
4579	/* release the uncleaned roots due to error */
4580	for (; i < ret; i++) {
4581		if (gang[i])
4582			btrfs_put_root(gang[i]);
4583	}
4584	return err;
4585}
4586
4587int btrfs_commit_super(struct btrfs_fs_info *fs_info)
4588{
4589	struct btrfs_root *root = fs_info->tree_root;
4590	struct btrfs_trans_handle *trans;
4591
4592	mutex_lock(&fs_info->cleaner_mutex);
4593	btrfs_run_delayed_iputs(fs_info);
4594	mutex_unlock(&fs_info->cleaner_mutex);
4595	wake_up_process(fs_info->cleaner_kthread);
4596
4597	/* wait until ongoing cleanup work done */
4598	down_write(&fs_info->cleanup_work_sem);
4599	up_write(&fs_info->cleanup_work_sem);
4600
4601	trans = btrfs_join_transaction(root);
4602	if (IS_ERR(trans))
4603		return PTR_ERR(trans);
4604	return btrfs_commit_transaction(trans);
4605}
4606
4607static void warn_about_uncommitted_trans(struct btrfs_fs_info *fs_info)
4608{
4609	struct btrfs_transaction *trans;
4610	struct btrfs_transaction *tmp;
4611	bool found = false;
4612
4613	if (list_empty(&fs_info->trans_list))
4614		return;
4615
4616	/*
4617	 * This function is only called at the very end of close_ctree(),
4618	 * thus no other running transaction, no need to take trans_lock.
4619	 */
4620	ASSERT(test_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags));
4621	list_for_each_entry_safe(trans, tmp, &fs_info->trans_list, list) {
4622		struct extent_state *cached = NULL;
4623		u64 dirty_bytes = 0;
4624		u64 cur = 0;
4625		u64 found_start;
4626		u64 found_end;
4627
4628		found = true;
4629		while (!find_first_extent_bit(&trans->dirty_pages, cur,
4630			&found_start, &found_end, EXTENT_DIRTY, &cached)) {
4631			dirty_bytes += found_end + 1 - found_start;
4632			cur = found_end + 1;
4633		}
4634		btrfs_warn(fs_info,
4635	"transaction %llu (with %llu dirty metadata bytes) is not committed",
4636			   trans->transid, dirty_bytes);
4637		btrfs_cleanup_one_transaction(trans, fs_info);
4638
4639		if (trans == fs_info->running_transaction)
4640			fs_info->running_transaction = NULL;
4641		list_del_init(&trans->list);
4642
4643		btrfs_put_transaction(trans);
4644		trace_btrfs_transaction_commit(fs_info);
4645	}
4646	ASSERT(!found);
4647}
4648
4649void __cold close_ctree(struct btrfs_fs_info *fs_info)
4650{
4651	int ret;
4652
4653	set_bit(BTRFS_FS_CLOSING_START, &fs_info->flags);
4654
4655	/*
4656	 * If we had UNFINISHED_DROPS we could still be processing them, so
4657	 * clear that bit and wake up relocation so it can stop.
4658	 * We must do this before stopping the block group reclaim task, because
4659	 * at btrfs_relocate_block_group() we wait for this bit, and after the
4660	 * wait we stop with -EINTR if btrfs_fs_closing() returns non-zero - we
4661	 * have just set BTRFS_FS_CLOSING_START, so btrfs_fs_closing() will
4662	 * return 1.
4663	 */
4664	btrfs_wake_unfinished_drop(fs_info);
4665
4666	/*
4667	 * We may have the reclaim task running and relocating a data block group,
4668	 * in which case it may create delayed iputs. So stop it before we park
4669	 * the cleaner kthread otherwise we can get new delayed iputs after
4670	 * parking the cleaner, and that can make the async reclaim task to hang
4671	 * if it's waiting for delayed iputs to complete, since the cleaner is
4672	 * parked and can not run delayed iputs - this will make us hang when
4673	 * trying to stop the async reclaim task.
4674	 */
4675	cancel_work_sync(&fs_info->reclaim_bgs_work);
4676	/*
4677	 * We don't want the cleaner to start new transactions, add more delayed
4678	 * iputs, etc. while we're closing. We can't use kthread_stop() yet
4679	 * because that frees the task_struct, and the transaction kthread might
4680	 * still try to wake up the cleaner.
4681	 */
4682	kthread_park(fs_info->cleaner_kthread);
4683
4684	/* wait for the qgroup rescan worker to stop */
4685	btrfs_qgroup_wait_for_completion(fs_info, false);
4686
4687	/* wait for the uuid_scan task to finish */
4688	down(&fs_info->uuid_tree_rescan_sem);
4689	/* avoid complains from lockdep et al., set sem back to initial state */
4690	up(&fs_info->uuid_tree_rescan_sem);
4691
4692	/* pause restriper - we want to resume on mount */
4693	btrfs_pause_balance(fs_info);
4694
4695	btrfs_dev_replace_suspend_for_unmount(fs_info);
4696
4697	btrfs_scrub_cancel(fs_info);
4698
4699	/* wait for any defraggers to finish */
4700	wait_event(fs_info->transaction_wait,
4701		   (atomic_read(&fs_info->defrag_running) == 0));
4702
4703	/* clear out the rbtree of defraggable inodes */
4704	btrfs_cleanup_defrag_inodes(fs_info);
4705
4706	/*
4707	 * After we parked the cleaner kthread, ordered extents may have
4708	 * completed and created new delayed iputs. If one of the async reclaim
4709	 * tasks is running and in the RUN_DELAYED_IPUTS flush state, then we
4710	 * can hang forever trying to stop it, because if a delayed iput is
4711	 * added after it ran btrfs_run_delayed_iputs() and before it called
4712	 * btrfs_wait_on_delayed_iputs(), it will hang forever since there is
4713	 * no one else to run iputs.
4714	 *
4715	 * So wait for all ongoing ordered extents to complete and then run
4716	 * delayed iputs. This works because once we reach this point no one
4717	 * can either create new ordered extents nor create delayed iputs
4718	 * through some other means.
4719	 *
4720	 * Also note that btrfs_wait_ordered_roots() is not safe here, because
4721	 * it waits for BTRFS_ORDERED_COMPLETE to be set on an ordered extent,
4722	 * but the delayed iput for the respective inode is made only when doing
4723	 * the final btrfs_put_ordered_extent() (which must happen at
4724	 * btrfs_finish_ordered_io() when we are unmounting).
4725	 */
4726	btrfs_flush_workqueue(fs_info->endio_write_workers);
4727	/* Ordered extents for free space inodes. */
4728	btrfs_flush_workqueue(fs_info->endio_freespace_worker);
4729	btrfs_run_delayed_iputs(fs_info);
4730
4731	cancel_work_sync(&fs_info->async_reclaim_work);
4732	cancel_work_sync(&fs_info->async_data_reclaim_work);
4733	cancel_work_sync(&fs_info->preempt_reclaim_work);
4734
4735	/* Cancel or finish ongoing discard work */
4736	btrfs_discard_cleanup(fs_info);
4737
4738	if (!sb_rdonly(fs_info->sb)) {
4739		/*
4740		 * The cleaner kthread is stopped, so do one final pass over
4741		 * unused block groups.
4742		 */
4743		btrfs_delete_unused_bgs(fs_info);
4744
4745		/*
4746		 * There might be existing delayed inode workers still running
4747		 * and holding an empty delayed inode item. We must wait for
4748		 * them to complete first because they can create a transaction.
4749		 * This happens when someone calls btrfs_balance_delayed_items()
4750		 * and then a transaction commit runs the same delayed nodes
4751		 * before any delayed worker has done something with the nodes.
4752		 * We must wait for any worker here and not at transaction
4753		 * commit time since that could cause a deadlock.
4754		 * This is a very rare case.
4755		 */
4756		btrfs_flush_workqueue(fs_info->delayed_workers);
4757
4758		ret = btrfs_commit_super(fs_info);
4759		if (ret)
4760			btrfs_err(fs_info, "commit super ret %d", ret);
4761	}
4762
4763	if (BTRFS_FS_ERROR(fs_info))
4764		btrfs_error_commit_super(fs_info);
4765
4766	kthread_stop(fs_info->transaction_kthread);
4767	kthread_stop(fs_info->cleaner_kthread);
4768
4769	ASSERT(list_empty(&fs_info->delayed_iputs));
4770	set_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags);
4771
4772	if (btrfs_check_quota_leak(fs_info)) {
4773		WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
4774		btrfs_err(fs_info, "qgroup reserved space leaked");
4775	}
4776
4777	btrfs_free_qgroup_config(fs_info);
4778	ASSERT(list_empty(&fs_info->delalloc_roots));
4779
4780	if (percpu_counter_sum(&fs_info->delalloc_bytes)) {
4781		btrfs_info(fs_info, "at unmount delalloc count %lld",
4782		       percpu_counter_sum(&fs_info->delalloc_bytes));
4783	}
4784
4785	if (percpu_counter_sum(&fs_info->ordered_bytes))
4786		btrfs_info(fs_info, "at unmount dio bytes count %lld",
4787			   percpu_counter_sum(&fs_info->ordered_bytes));
4788
4789	btrfs_sysfs_remove_mounted(fs_info);
4790	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
4791
4792	btrfs_put_block_group_cache(fs_info);
4793
4794	/*
4795	 * we must make sure there is not any read request to
4796	 * submit after we stopping all workers.
4797	 */
4798	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
4799	btrfs_stop_all_workers(fs_info);
4800
4801	/* We shouldn't have any transaction open at this point */
4802	warn_about_uncommitted_trans(fs_info);
4803
4804	clear_bit(BTRFS_FS_OPEN, &fs_info->flags);
4805	free_root_pointers(fs_info, true);
4806	btrfs_free_fs_roots(fs_info);
4807
4808	/*
4809	 * We must free the block groups after dropping the fs_roots as we could
4810	 * have had an IO error and have left over tree log blocks that aren't
4811	 * cleaned up until the fs roots are freed.  This makes the block group
4812	 * accounting appear to be wrong because there's pending reserved bytes,
4813	 * so make sure we do the block group cleanup afterwards.
4814	 */
4815	btrfs_free_block_groups(fs_info);
4816
4817	iput(fs_info->btree_inode);
4818
4819#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4820	if (btrfs_test_opt(fs_info, CHECK_INTEGRITY))
4821		btrfsic_unmount(fs_info->fs_devices);
4822#endif
4823
4824	btrfs_mapping_tree_free(&fs_info->mapping_tree);
4825	btrfs_close_devices(fs_info->fs_devices);
4826}
4827
4828int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
4829			  int atomic)
4830{
4831	int ret;
4832	struct inode *btree_inode = buf->pages[0]->mapping->host;
4833
4834	ret = extent_buffer_uptodate(buf);
4835	if (!ret)
4836		return ret;
4837
4838	ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
4839				    parent_transid, atomic);
4840	if (ret == -EAGAIN)
4841		return ret;
4842	return !ret;
4843}
4844
4845void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
4846{
4847	struct btrfs_fs_info *fs_info = buf->fs_info;
4848	u64 transid = btrfs_header_generation(buf);
4849	int was_dirty;
4850
4851#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4852	/*
4853	 * This is a fast path so only do this check if we have sanity tests
4854	 * enabled.  Normal people shouldn't be using unmapped buffers as dirty
4855	 * outside of the sanity tests.
4856	 */
4857	if (unlikely(test_bit(EXTENT_BUFFER_UNMAPPED, &buf->bflags)))
4858		return;
4859#endif
 
 
4860	btrfs_assert_tree_write_locked(buf);
4861	if (transid != fs_info->generation)
4862		WARN(1, KERN_CRIT "btrfs transid mismatch buffer %llu, found %llu running %llu\n",
4863			buf->start, transid, fs_info->generation);
4864	was_dirty = set_extent_buffer_dirty(buf);
4865	if (!was_dirty)
4866		percpu_counter_add_batch(&fs_info->dirty_metadata_bytes,
4867					 buf->len,
4868					 fs_info->dirty_metadata_batch);
4869#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4870	/*
4871	 * Since btrfs_mark_buffer_dirty() can be called with item pointer set
4872	 * but item data not updated.
4873	 * So here we should only check item pointers, not item data.
4874	 */
4875	if (btrfs_header_level(buf) == 0 &&
4876	    btrfs_check_leaf_relaxed(buf)) {
4877		btrfs_print_leaf(buf);
4878		ASSERT(0);
4879	}
4880#endif
4881}
4882
4883static void __btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info,
4884					int flush_delayed)
4885{
4886	/*
4887	 * looks as though older kernels can get into trouble with
4888	 * this code, they end up stuck in balance_dirty_pages forever
4889	 */
4890	int ret;
4891
4892	if (current->flags & PF_MEMALLOC)
4893		return;
4894
4895	if (flush_delayed)
4896		btrfs_balance_delayed_items(fs_info);
4897
4898	ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
4899				     BTRFS_DIRTY_METADATA_THRESH,
4900				     fs_info->dirty_metadata_batch);
4901	if (ret > 0) {
4902		balance_dirty_pages_ratelimited(fs_info->btree_inode->i_mapping);
4903	}
4904}
4905
4906void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info)
4907{
4908	__btrfs_btree_balance_dirty(fs_info, 1);
4909}
4910
4911void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info)
4912{
4913	__btrfs_btree_balance_dirty(fs_info, 0);
4914}
4915
4916static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info)
4917{
4918	/* cleanup FS via transaction */
4919	btrfs_cleanup_transaction(fs_info);
4920
4921	mutex_lock(&fs_info->cleaner_mutex);
4922	btrfs_run_delayed_iputs(fs_info);
4923	mutex_unlock(&fs_info->cleaner_mutex);
4924
4925	down_write(&fs_info->cleanup_work_sem);
4926	up_write(&fs_info->cleanup_work_sem);
4927}
4928
4929static void btrfs_drop_all_logs(struct btrfs_fs_info *fs_info)
4930{
4931	struct btrfs_root *gang[8];
4932	u64 root_objectid = 0;
4933	int ret;
4934
4935	spin_lock(&fs_info->fs_roots_radix_lock);
4936	while ((ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
4937					     (void **)gang, root_objectid,
4938					     ARRAY_SIZE(gang))) != 0) {
4939		int i;
4940
4941		for (i = 0; i < ret; i++)
4942			gang[i] = btrfs_grab_root(gang[i]);
4943		spin_unlock(&fs_info->fs_roots_radix_lock);
4944
4945		for (i = 0; i < ret; i++) {
4946			if (!gang[i])
4947				continue;
4948			root_objectid = gang[i]->root_key.objectid;
4949			btrfs_free_log(NULL, gang[i]);
4950			btrfs_put_root(gang[i]);
4951		}
4952		root_objectid++;
4953		spin_lock(&fs_info->fs_roots_radix_lock);
4954	}
4955	spin_unlock(&fs_info->fs_roots_radix_lock);
4956	btrfs_free_log_root_tree(NULL, fs_info);
4957}
4958
4959static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
4960{
4961	struct btrfs_ordered_extent *ordered;
4962
4963	spin_lock(&root->ordered_extent_lock);
4964	/*
4965	 * This will just short circuit the ordered completion stuff which will
4966	 * make sure the ordered extent gets properly cleaned up.
4967	 */
4968	list_for_each_entry(ordered, &root->ordered_extents,
4969			    root_extent_list)
4970		set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
4971	spin_unlock(&root->ordered_extent_lock);
4972}
4973
4974static void btrfs_destroy_all_ordered_extents(struct btrfs_fs_info *fs_info)
4975{
4976	struct btrfs_root *root;
4977	struct list_head splice;
4978
4979	INIT_LIST_HEAD(&splice);
4980
4981	spin_lock(&fs_info->ordered_root_lock);
4982	list_splice_init(&fs_info->ordered_roots, &splice);
4983	while (!list_empty(&splice)) {
4984		root = list_first_entry(&splice, struct btrfs_root,
4985					ordered_root);
4986		list_move_tail(&root->ordered_root,
4987			       &fs_info->ordered_roots);
4988
4989		spin_unlock(&fs_info->ordered_root_lock);
4990		btrfs_destroy_ordered_extents(root);
4991
4992		cond_resched();
4993		spin_lock(&fs_info->ordered_root_lock);
4994	}
4995	spin_unlock(&fs_info->ordered_root_lock);
4996
4997	/*
4998	 * We need this here because if we've been flipped read-only we won't
4999	 * get sync() from the umount, so we need to make sure any ordered
5000	 * extents that haven't had their dirty pages IO start writeout yet
5001	 * actually get run and error out properly.
5002	 */
5003	btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
5004}
5005
5006static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
5007				      struct btrfs_fs_info *fs_info)
5008{
5009	struct rb_node *node;
5010	struct btrfs_delayed_ref_root *delayed_refs;
5011	struct btrfs_delayed_ref_node *ref;
5012	int ret = 0;
5013
5014	delayed_refs = &trans->delayed_refs;
5015
5016	spin_lock(&delayed_refs->lock);
5017	if (atomic_read(&delayed_refs->num_entries) == 0) {
5018		spin_unlock(&delayed_refs->lock);
5019		btrfs_debug(fs_info, "delayed_refs has NO entry");
5020		return ret;
5021	}
5022
5023	while ((node = rb_first_cached(&delayed_refs->href_root)) != NULL) {
5024		struct btrfs_delayed_ref_head *head;
5025		struct rb_node *n;
5026		bool pin_bytes = false;
5027
5028		head = rb_entry(node, struct btrfs_delayed_ref_head,
5029				href_node);
5030		if (btrfs_delayed_ref_lock(delayed_refs, head))
5031			continue;
5032
5033		spin_lock(&head->lock);
5034		while ((n = rb_first_cached(&head->ref_tree)) != NULL) {
5035			ref = rb_entry(n, struct btrfs_delayed_ref_node,
5036				       ref_node);
5037			ref->in_tree = 0;
5038			rb_erase_cached(&ref->ref_node, &head->ref_tree);
5039			RB_CLEAR_NODE(&ref->ref_node);
5040			if (!list_empty(&ref->add_list))
5041				list_del(&ref->add_list);
5042			atomic_dec(&delayed_refs->num_entries);
5043			btrfs_put_delayed_ref(ref);
 
5044		}
5045		if (head->must_insert_reserved)
5046			pin_bytes = true;
5047		btrfs_free_delayed_extent_op(head->extent_op);
5048		btrfs_delete_ref_head(delayed_refs, head);
5049		spin_unlock(&head->lock);
5050		spin_unlock(&delayed_refs->lock);
5051		mutex_unlock(&head->mutex);
5052
5053		if (pin_bytes) {
5054			struct btrfs_block_group *cache;
5055
5056			cache = btrfs_lookup_block_group(fs_info, head->bytenr);
5057			BUG_ON(!cache);
5058
5059			spin_lock(&cache->space_info->lock);
5060			spin_lock(&cache->lock);
5061			cache->pinned += head->num_bytes;
5062			btrfs_space_info_update_bytes_pinned(fs_info,
5063				cache->space_info, head->num_bytes);
5064			cache->reserved -= head->num_bytes;
5065			cache->space_info->bytes_reserved -= head->num_bytes;
5066			spin_unlock(&cache->lock);
5067			spin_unlock(&cache->space_info->lock);
5068
5069			btrfs_put_block_group(cache);
5070
5071			btrfs_error_unpin_extent_range(fs_info, head->bytenr,
5072				head->bytenr + head->num_bytes - 1);
5073		}
5074		btrfs_cleanup_ref_head_accounting(fs_info, delayed_refs, head);
5075		btrfs_put_delayed_ref_head(head);
5076		cond_resched();
5077		spin_lock(&delayed_refs->lock);
5078	}
5079	btrfs_qgroup_destroy_extent_records(trans);
5080
5081	spin_unlock(&delayed_refs->lock);
5082
5083	return ret;
5084}
5085
5086static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
5087{
5088	struct btrfs_inode *btrfs_inode;
5089	struct list_head splice;
5090
5091	INIT_LIST_HEAD(&splice);
5092
5093	spin_lock(&root->delalloc_lock);
5094	list_splice_init(&root->delalloc_inodes, &splice);
5095
5096	while (!list_empty(&splice)) {
5097		struct inode *inode = NULL;
5098		btrfs_inode = list_first_entry(&splice, struct btrfs_inode,
5099					       delalloc_inodes);
5100		__btrfs_del_delalloc_inode(root, btrfs_inode);
5101		spin_unlock(&root->delalloc_lock);
5102
5103		/*
5104		 * Make sure we get a live inode and that it'll not disappear
5105		 * meanwhile.
5106		 */
5107		inode = igrab(&btrfs_inode->vfs_inode);
5108		if (inode) {
 
 
 
5109			invalidate_inode_pages2(inode->i_mapping);
 
5110			iput(inode);
5111		}
5112		spin_lock(&root->delalloc_lock);
5113	}
5114	spin_unlock(&root->delalloc_lock);
5115}
5116
5117static void btrfs_destroy_all_delalloc_inodes(struct btrfs_fs_info *fs_info)
5118{
5119	struct btrfs_root *root;
5120	struct list_head splice;
5121
5122	INIT_LIST_HEAD(&splice);
5123
5124	spin_lock(&fs_info->delalloc_root_lock);
5125	list_splice_init(&fs_info->delalloc_roots, &splice);
5126	while (!list_empty(&splice)) {
5127		root = list_first_entry(&splice, struct btrfs_root,
5128					 delalloc_root);
5129		root = btrfs_grab_root(root);
5130		BUG_ON(!root);
5131		spin_unlock(&fs_info->delalloc_root_lock);
5132
5133		btrfs_destroy_delalloc_inodes(root);
5134		btrfs_put_root(root);
5135
5136		spin_lock(&fs_info->delalloc_root_lock);
5137	}
5138	spin_unlock(&fs_info->delalloc_root_lock);
5139}
5140
5141static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
5142					struct extent_io_tree *dirty_pages,
5143					int mark)
5144{
5145	int ret;
5146	struct extent_buffer *eb;
5147	u64 start = 0;
5148	u64 end;
5149
5150	while (1) {
5151		ret = find_first_extent_bit(dirty_pages, start, &start, &end,
5152					    mark, NULL);
5153		if (ret)
5154			break;
5155
5156		clear_extent_bits(dirty_pages, start, end, mark);
5157		while (start <= end) {
5158			eb = find_extent_buffer(fs_info, start);
5159			start += fs_info->nodesize;
5160			if (!eb)
5161				continue;
 
 
5162			wait_on_extent_buffer_writeback(eb);
 
 
5163
5164			if (test_and_clear_bit(EXTENT_BUFFER_DIRTY,
5165					       &eb->bflags))
5166				clear_extent_buffer_dirty(eb);
5167			free_extent_buffer_stale(eb);
5168		}
5169	}
5170
5171	return ret;
5172}
5173
5174static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
5175				       struct extent_io_tree *unpin)
5176{
5177	u64 start;
5178	u64 end;
5179	int ret;
5180
5181	while (1) {
5182		struct extent_state *cached_state = NULL;
5183
5184		/*
5185		 * The btrfs_finish_extent_commit() may get the same range as
5186		 * ours between find_first_extent_bit and clear_extent_dirty.
5187		 * Hence, hold the unused_bg_unpin_mutex to avoid double unpin
5188		 * the same extent range.
5189		 */
5190		mutex_lock(&fs_info->unused_bg_unpin_mutex);
5191		ret = find_first_extent_bit(unpin, 0, &start, &end,
5192					    EXTENT_DIRTY, &cached_state);
5193		if (ret) {
5194			mutex_unlock(&fs_info->unused_bg_unpin_mutex);
5195			break;
5196		}
5197
5198		clear_extent_dirty(unpin, start, end, &cached_state);
5199		free_extent_state(cached_state);
5200		btrfs_error_unpin_extent_range(fs_info, start, end);
5201		mutex_unlock(&fs_info->unused_bg_unpin_mutex);
5202		cond_resched();
5203	}
5204
5205	return 0;
5206}
5207
5208static void btrfs_cleanup_bg_io(struct btrfs_block_group *cache)
5209{
5210	struct inode *inode;
5211
5212	inode = cache->io_ctl.inode;
5213	if (inode) {
 
 
 
5214		invalidate_inode_pages2(inode->i_mapping);
 
 
5215		BTRFS_I(inode)->generation = 0;
5216		cache->io_ctl.inode = NULL;
5217		iput(inode);
5218	}
5219	ASSERT(cache->io_ctl.pages == NULL);
5220	btrfs_put_block_group(cache);
5221}
5222
5223void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *cur_trans,
5224			     struct btrfs_fs_info *fs_info)
5225{
5226	struct btrfs_block_group *cache;
5227
5228	spin_lock(&cur_trans->dirty_bgs_lock);
5229	while (!list_empty(&cur_trans->dirty_bgs)) {
5230		cache = list_first_entry(&cur_trans->dirty_bgs,
5231					 struct btrfs_block_group,
5232					 dirty_list);
5233
5234		if (!list_empty(&cache->io_list)) {
5235			spin_unlock(&cur_trans->dirty_bgs_lock);
5236			list_del_init(&cache->io_list);
5237			btrfs_cleanup_bg_io(cache);
5238			spin_lock(&cur_trans->dirty_bgs_lock);
5239		}
5240
5241		list_del_init(&cache->dirty_list);
5242		spin_lock(&cache->lock);
5243		cache->disk_cache_state = BTRFS_DC_ERROR;
5244		spin_unlock(&cache->lock);
5245
5246		spin_unlock(&cur_trans->dirty_bgs_lock);
5247		btrfs_put_block_group(cache);
5248		btrfs_delayed_refs_rsv_release(fs_info, 1);
5249		spin_lock(&cur_trans->dirty_bgs_lock);
5250	}
5251	spin_unlock(&cur_trans->dirty_bgs_lock);
5252
5253	/*
5254	 * Refer to the definition of io_bgs member for details why it's safe
5255	 * to use it without any locking
5256	 */
5257	while (!list_empty(&cur_trans->io_bgs)) {
5258		cache = list_first_entry(&cur_trans->io_bgs,
5259					 struct btrfs_block_group,
5260					 io_list);
5261
5262		list_del_init(&cache->io_list);
5263		spin_lock(&cache->lock);
5264		cache->disk_cache_state = BTRFS_DC_ERROR;
5265		spin_unlock(&cache->lock);
5266		btrfs_cleanup_bg_io(cache);
5267	}
5268}
5269
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5270void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
5271				   struct btrfs_fs_info *fs_info)
5272{
5273	struct btrfs_device *dev, *tmp;
5274
5275	btrfs_cleanup_dirty_bgs(cur_trans, fs_info);
5276	ASSERT(list_empty(&cur_trans->dirty_bgs));
5277	ASSERT(list_empty(&cur_trans->io_bgs));
5278
5279	list_for_each_entry_safe(dev, tmp, &cur_trans->dev_update_list,
5280				 post_commit_list) {
5281		list_del_init(&dev->post_commit_list);
5282	}
5283
5284	btrfs_destroy_delayed_refs(cur_trans, fs_info);
5285
5286	cur_trans->state = TRANS_STATE_COMMIT_START;
5287	wake_up(&fs_info->transaction_blocked_wait);
5288
5289	cur_trans->state = TRANS_STATE_UNBLOCKED;
5290	wake_up(&fs_info->transaction_wait);
5291
5292	btrfs_destroy_delayed_inodes(fs_info);
5293
5294	btrfs_destroy_marked_extents(fs_info, &cur_trans->dirty_pages,
5295				     EXTENT_DIRTY);
5296	btrfs_destroy_pinned_extent(fs_info, &cur_trans->pinned_extents);
5297
5298	btrfs_free_redirty_list(cur_trans);
5299
5300	cur_trans->state =TRANS_STATE_COMPLETED;
5301	wake_up(&cur_trans->commit_wait);
5302}
5303
5304static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info)
5305{
5306	struct btrfs_transaction *t;
5307
5308	mutex_lock(&fs_info->transaction_kthread_mutex);
5309
5310	spin_lock(&fs_info->trans_lock);
5311	while (!list_empty(&fs_info->trans_list)) {
5312		t = list_first_entry(&fs_info->trans_list,
5313				     struct btrfs_transaction, list);
5314		if (t->state >= TRANS_STATE_COMMIT_START) {
5315			refcount_inc(&t->use_count);
5316			spin_unlock(&fs_info->trans_lock);
5317			btrfs_wait_for_commit(fs_info, t->transid);
5318			btrfs_put_transaction(t);
5319			spin_lock(&fs_info->trans_lock);
5320			continue;
5321		}
5322		if (t == fs_info->running_transaction) {
5323			t->state = TRANS_STATE_COMMIT_DOING;
5324			spin_unlock(&fs_info->trans_lock);
5325			/*
5326			 * We wait for 0 num_writers since we don't hold a trans
5327			 * handle open currently for this transaction.
5328			 */
5329			wait_event(t->writer_wait,
5330				   atomic_read(&t->num_writers) == 0);
5331		} else {
5332			spin_unlock(&fs_info->trans_lock);
5333		}
5334		btrfs_cleanup_one_transaction(t, fs_info);
5335
5336		spin_lock(&fs_info->trans_lock);
5337		if (t == fs_info->running_transaction)
5338			fs_info->running_transaction = NULL;
5339		list_del_init(&t->list);
5340		spin_unlock(&fs_info->trans_lock);
5341
5342		btrfs_put_transaction(t);
5343		trace_btrfs_transaction_commit(fs_info);
5344		spin_lock(&fs_info->trans_lock);
5345	}
5346	spin_unlock(&fs_info->trans_lock);
5347	btrfs_destroy_all_ordered_extents(fs_info);
5348	btrfs_destroy_delayed_inodes(fs_info);
5349	btrfs_assert_delayed_root_empty(fs_info);
5350	btrfs_destroy_all_delalloc_inodes(fs_info);
5351	btrfs_drop_all_logs(fs_info);
5352	mutex_unlock(&fs_info->transaction_kthread_mutex);
5353
5354	return 0;
5355}
5356
5357int btrfs_init_root_free_objectid(struct btrfs_root *root)
5358{
5359	struct btrfs_path *path;
5360	int ret;
5361	struct extent_buffer *l;
5362	struct btrfs_key search_key;
5363	struct btrfs_key found_key;
5364	int slot;
5365
5366	path = btrfs_alloc_path();
5367	if (!path)
5368		return -ENOMEM;
5369
5370	search_key.objectid = BTRFS_LAST_FREE_OBJECTID;
5371	search_key.type = -1;
5372	search_key.offset = (u64)-1;
5373	ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
5374	if (ret < 0)
5375		goto error;
5376	BUG_ON(ret == 0); /* Corruption */
5377	if (path->slots[0] > 0) {
5378		slot = path->slots[0] - 1;
5379		l = path->nodes[0];
5380		btrfs_item_key_to_cpu(l, &found_key, slot);
5381		root->free_objectid = max_t(u64, found_key.objectid + 1,
5382					    BTRFS_FIRST_FREE_OBJECTID);
5383	} else {
5384		root->free_objectid = BTRFS_FIRST_FREE_OBJECTID;
5385	}
5386	ret = 0;
5387error:
5388	btrfs_free_path(path);
5389	return ret;
5390}
5391
5392int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid)
5393{
5394	int ret;
5395	mutex_lock(&root->objectid_mutex);
5396
5397	if (unlikely(root->free_objectid >= BTRFS_LAST_FREE_OBJECTID)) {
5398		btrfs_warn(root->fs_info,
5399			   "the objectid of root %llu reaches its highest value",
5400			   root->root_key.objectid);
5401		ret = -ENOSPC;
5402		goto out;
5403	}
5404
5405	*objectid = root->free_objectid++;
5406	ret = 0;
5407out:
5408	mutex_unlock(&root->objectid_mutex);
5409	return ret;
5410}