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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}
v5.14.15
   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 "volumes.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
  47#define BTRFS_SUPER_FLAG_SUPP	(BTRFS_HEADER_FLAG_WRITTEN |\
  48				 BTRFS_HEADER_FLAG_RELOC |\
  49				 BTRFS_SUPER_FLAG_ERROR |\
  50				 BTRFS_SUPER_FLAG_SEEDING |\
  51				 BTRFS_SUPER_FLAG_METADUMP |\
  52				 BTRFS_SUPER_FLAG_METADUMP_V2)
  53
  54static void end_workqueue_fn(struct btrfs_work *work);
  55static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
  56static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
  57				      struct btrfs_fs_info *fs_info);
  58static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
  59static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
  60					struct extent_io_tree *dirty_pages,
  61					int mark);
  62static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
  63				       struct extent_io_tree *pinned_extents);
  64static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info);
  65static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info);
  66
  67/*
  68 * btrfs_end_io_wq structs are used to do processing in task context when an IO
  69 * is complete.  This is used during reads to verify checksums, and it is used
  70 * by writes to insert metadata for new file extents after IO is complete.
  71 */
  72struct btrfs_end_io_wq {
  73	struct bio *bio;
  74	bio_end_io_t *end_io;
  75	void *private;
  76	struct btrfs_fs_info *info;
  77	blk_status_t status;
  78	enum btrfs_wq_endio_type metadata;
  79	struct btrfs_work work;
  80};
  81
  82static struct kmem_cache *btrfs_end_io_wq_cache;
  83
  84int __init btrfs_end_io_wq_init(void)
  85{
  86	btrfs_end_io_wq_cache = kmem_cache_create("btrfs_end_io_wq",
  87					sizeof(struct btrfs_end_io_wq),
  88					0,
  89					SLAB_MEM_SPREAD,
  90					NULL);
  91	if (!btrfs_end_io_wq_cache)
  92		return -ENOMEM;
  93	return 0;
  94}
  95
  96void __cold btrfs_end_io_wq_exit(void)
  97{
  98	kmem_cache_destroy(btrfs_end_io_wq_cache);
  99}
 100
 101static void btrfs_free_csum_hash(struct btrfs_fs_info *fs_info)
 102{
 103	if (fs_info->csum_shash)
 104		crypto_free_shash(fs_info->csum_shash);
 105}
 106
 107/*
 108 * async submit bios are used to offload expensive checksumming
 109 * onto the worker threads.  They checksum file and metadata bios
 110 * just before they are sent down the IO stack.
 111 */
 112struct async_submit_bio {
 113	struct inode *inode;
 114	struct bio *bio;
 115	extent_submit_bio_start_t *submit_bio_start;
 116	int mirror_num;
 117
 118	/* Optional parameter for submit_bio_start used by direct io */
 119	u64 dio_file_offset;
 120	struct btrfs_work work;
 121	blk_status_t status;
 122};
 123
 124/*
 125 * Lockdep class keys for extent_buffer->lock's in this root.  For a given
 126 * eb, the lockdep key is determined by the btrfs_root it belongs to and
 127 * the level the eb occupies in the tree.
 128 *
 129 * Different roots are used for different purposes and may nest inside each
 130 * other and they require separate keysets.  As lockdep keys should be
 131 * static, assign keysets according to the purpose of the root as indicated
 132 * by btrfs_root->root_key.objectid.  This ensures that all special purpose
 133 * roots have separate keysets.
 134 *
 135 * Lock-nesting across peer nodes is always done with the immediate parent
 136 * node locked thus preventing deadlock.  As lockdep doesn't know this, use
 137 * subclass to avoid triggering lockdep warning in such cases.
 138 *
 139 * The key is set by the readpage_end_io_hook after the buffer has passed
 140 * csum validation but before the pages are unlocked.  It is also set by
 141 * btrfs_init_new_buffer on freshly allocated blocks.
 142 *
 143 * We also add a check to make sure the highest level of the tree is the
 144 * same as our lockdep setup here.  If BTRFS_MAX_LEVEL changes, this code
 145 * needs update as well.
 146 */
 147#ifdef CONFIG_DEBUG_LOCK_ALLOC
 148# if BTRFS_MAX_LEVEL != 8
 149#  error
 150# endif
 151
 152#define DEFINE_LEVEL(stem, level)					\
 153	.names[level] = "btrfs-" stem "-0" #level,
 154
 155#define DEFINE_NAME(stem)						\
 156	DEFINE_LEVEL(stem, 0)						\
 157	DEFINE_LEVEL(stem, 1)						\
 158	DEFINE_LEVEL(stem, 2)						\
 159	DEFINE_LEVEL(stem, 3)						\
 160	DEFINE_LEVEL(stem, 4)						\
 161	DEFINE_LEVEL(stem, 5)						\
 162	DEFINE_LEVEL(stem, 6)						\
 163	DEFINE_LEVEL(stem, 7)
 164
 165static struct btrfs_lockdep_keyset {
 166	u64			id;		/* root objectid */
 167	/* Longest entry: btrfs-free-space-00 */
 168	char			names[BTRFS_MAX_LEVEL][20];
 169	struct lock_class_key	keys[BTRFS_MAX_LEVEL];
 170} btrfs_lockdep_keysets[] = {
 171	{ .id = BTRFS_ROOT_TREE_OBJECTID,	DEFINE_NAME("root")	},
 172	{ .id = BTRFS_EXTENT_TREE_OBJECTID,	DEFINE_NAME("extent")	},
 173	{ .id = BTRFS_CHUNK_TREE_OBJECTID,	DEFINE_NAME("chunk")	},
 174	{ .id = BTRFS_DEV_TREE_OBJECTID,	DEFINE_NAME("dev")	},
 175	{ .id = BTRFS_CSUM_TREE_OBJECTID,	DEFINE_NAME("csum")	},
 176	{ .id = BTRFS_QUOTA_TREE_OBJECTID,	DEFINE_NAME("quota")	},
 177	{ .id = BTRFS_TREE_LOG_OBJECTID,	DEFINE_NAME("log")	},
 178	{ .id = BTRFS_TREE_RELOC_OBJECTID,	DEFINE_NAME("treloc")	},
 179	{ .id = BTRFS_DATA_RELOC_TREE_OBJECTID,	DEFINE_NAME("dreloc")	},
 180	{ .id = BTRFS_UUID_TREE_OBJECTID,	DEFINE_NAME("uuid")	},
 181	{ .id = BTRFS_FREE_SPACE_TREE_OBJECTID,	DEFINE_NAME("free-space") },
 182	{ .id = 0,				DEFINE_NAME("tree")	},
 183};
 184
 185#undef DEFINE_LEVEL
 186#undef DEFINE_NAME
 187
 188void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
 189				    int level)
 190{
 191	struct btrfs_lockdep_keyset *ks;
 192
 193	BUG_ON(level >= ARRAY_SIZE(ks->keys));
 194
 195	/* find the matching keyset, id 0 is the default entry */
 196	for (ks = btrfs_lockdep_keysets; ks->id; ks++)
 197		if (ks->id == objectid)
 198			break;
 199
 200	lockdep_set_class_and_name(&eb->lock,
 201				   &ks->keys[level], ks->names[level]);
 202}
 203
 204#endif
 205
 206/*
 207 * Compute the csum of a btree block and store the result to provided buffer.
 208 */
 209static void csum_tree_block(struct extent_buffer *buf, u8 *result)
 210{
 211	struct btrfs_fs_info *fs_info = buf->fs_info;
 212	const int num_pages = num_extent_pages(buf);
 213	const int first_page_part = min_t(u32, PAGE_SIZE, fs_info->nodesize);
 214	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 215	char *kaddr;
 216	int i;
 217
 218	shash->tfm = fs_info->csum_shash;
 219	crypto_shash_init(shash);
 220	kaddr = page_address(buf->pages[0]) + offset_in_page(buf->start);
 
 
 
 
 
 
 
 
 
 
 
 221	crypto_shash_update(shash, kaddr + BTRFS_CSUM_SIZE,
 222			    first_page_part - BTRFS_CSUM_SIZE);
 223
 224	for (i = 1; i < num_pages; i++) {
 225		kaddr = page_address(buf->pages[i]);
 
 
 
 
 
 
 226		crypto_shash_update(shash, kaddr, PAGE_SIZE);
 227	}
 228	memset(result, 0, BTRFS_CSUM_SIZE);
 229	crypto_shash_final(shash, result);
 230}
 231
 232/*
 233 * we can't consider a given block up to date unless the transid of the
 234 * block matches the transid in the parent node's pointer.  This is how we
 235 * detect blocks that either didn't get written at all or got written
 236 * in the wrong place.
 237 */
 238static int verify_parent_transid(struct extent_io_tree *io_tree,
 239				 struct extent_buffer *eb, u64 parent_transid,
 240				 int atomic)
 241{
 242	struct extent_state *cached_state = NULL;
 243	int ret;
 244
 245	if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 246		return 0;
 247
 248	if (atomic)
 249		return -EAGAIN;
 250
 251	lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
 252			 &cached_state);
 253	if (extent_buffer_uptodate(eb) &&
 254	    btrfs_header_generation(eb) == parent_transid) {
 255		ret = 0;
 256		goto out;
 
 
 257	}
 258	btrfs_err_rl(eb->fs_info,
 259		"parent transid verify failed on %llu wanted %llu found %llu",
 260			eb->start,
 261			parent_transid, btrfs_header_generation(eb));
 262	ret = 1;
 263	clear_extent_buffer_uptodate(eb);
 264out:
 265	unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
 266			     &cached_state);
 267	return ret;
 268}
 269
 270static bool btrfs_supported_super_csum(u16 csum_type)
 271{
 272	switch (csum_type) {
 273	case BTRFS_CSUM_TYPE_CRC32:
 274	case BTRFS_CSUM_TYPE_XXHASH:
 275	case BTRFS_CSUM_TYPE_SHA256:
 276	case BTRFS_CSUM_TYPE_BLAKE2:
 277		return true;
 278	default:
 279		return false;
 280	}
 281}
 282
 283/*
 284 * Return 0 if the superblock checksum type matches the checksum value of that
 285 * algorithm. Pass the raw disk superblock data.
 286 */
 287static int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
 288				  char *raw_disk_sb)
 289{
 290	struct btrfs_super_block *disk_sb =
 291		(struct btrfs_super_block *)raw_disk_sb;
 292	char result[BTRFS_CSUM_SIZE];
 293	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 294
 295	shash->tfm = fs_info->csum_shash;
 296
 297	/*
 298	 * The super_block structure does not span the whole
 299	 * BTRFS_SUPER_INFO_SIZE range, we expect that the unused space is
 300	 * filled with zeros and is included in the checksum.
 301	 */
 302	crypto_shash_digest(shash, raw_disk_sb + BTRFS_CSUM_SIZE,
 303			    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE, result);
 304
 305	if (memcmp(disk_sb->csum, result, fs_info->csum_size))
 306		return 1;
 307
 308	return 0;
 309}
 310
 311int btrfs_verify_level_key(struct extent_buffer *eb, int level,
 312			   struct btrfs_key *first_key, u64 parent_transid)
 313{
 314	struct btrfs_fs_info *fs_info = eb->fs_info;
 315	int found_level;
 316	struct btrfs_key found_key;
 317	int ret;
 318
 319	found_level = btrfs_header_level(eb);
 320	if (found_level != level) {
 321		WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
 322		     KERN_ERR "BTRFS: tree level check failed\n");
 323		btrfs_err(fs_info,
 324"tree level mismatch detected, bytenr=%llu level expected=%u has=%u",
 325			  eb->start, level, found_level);
 326		return -EIO;
 327	}
 328
 329	if (!first_key)
 330		return 0;
 331
 332	/*
 333	 * For live tree block (new tree blocks in current transaction),
 334	 * we need proper lock context to avoid race, which is impossible here.
 335	 * So we only checks tree blocks which is read from disk, whose
 336	 * generation <= fs_info->last_trans_committed.
 337	 */
 338	if (btrfs_header_generation(eb) > fs_info->last_trans_committed)
 339		return 0;
 340
 341	/* We have @first_key, so this @eb must have at least one item */
 342	if (btrfs_header_nritems(eb) == 0) {
 343		btrfs_err(fs_info,
 344		"invalid tree nritems, bytenr=%llu nritems=0 expect >0",
 345			  eb->start);
 346		WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
 347		return -EUCLEAN;
 348	}
 349
 350	if (found_level)
 351		btrfs_node_key_to_cpu(eb, &found_key, 0);
 352	else
 353		btrfs_item_key_to_cpu(eb, &found_key, 0);
 354	ret = btrfs_comp_cpu_keys(first_key, &found_key);
 355
 356	if (ret) {
 357		WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
 358		     KERN_ERR "BTRFS: tree first key check failed\n");
 359		btrfs_err(fs_info,
 360"tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
 361			  eb->start, parent_transid, first_key->objectid,
 362			  first_key->type, first_key->offset,
 363			  found_key.objectid, found_key.type,
 364			  found_key.offset);
 365	}
 366	return ret;
 367}
 368
 369/*
 370 * helper to read a given tree block, doing retries as required when
 371 * the checksums don't match and we have alternate mirrors to try.
 372 *
 373 * @parent_transid:	expected transid, skip check if 0
 374 * @level:		expected level, mandatory check
 375 * @first_key:		expected key of first slot, skip check if NULL
 376 */
 377static int btree_read_extent_buffer_pages(struct extent_buffer *eb,
 378					  u64 parent_transid, int level,
 379					  struct btrfs_key *first_key)
 380{
 381	struct btrfs_fs_info *fs_info = eb->fs_info;
 382	struct extent_io_tree *io_tree;
 383	int failed = 0;
 384	int ret;
 385	int num_copies = 0;
 386	int mirror_num = 0;
 387	int failed_mirror = 0;
 388
 389	io_tree = &BTRFS_I(fs_info->btree_inode)->io_tree;
 
 390	while (1) {
 391		clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 392		ret = read_extent_buffer_pages(eb, WAIT_COMPLETE, mirror_num);
 393		if (!ret) {
 394			if (verify_parent_transid(io_tree, eb,
 395						   parent_transid, 0))
 396				ret = -EIO;
 397			else if (btrfs_verify_level_key(eb, level,
 398						first_key, parent_transid))
 399				ret = -EUCLEAN;
 400			else
 401				break;
 402		}
 403
 404		num_copies = btrfs_num_copies(fs_info,
 405					      eb->start, eb->len);
 406		if (num_copies == 1)
 407			break;
 408
 409		if (!failed_mirror) {
 410			failed = 1;
 411			failed_mirror = eb->read_mirror;
 412		}
 413
 414		mirror_num++;
 415		if (mirror_num == failed_mirror)
 416			mirror_num++;
 417
 418		if (mirror_num > num_copies)
 419			break;
 420	}
 421
 422	if (failed && !ret && failed_mirror)
 423		btrfs_repair_eb_io_failure(eb, failed_mirror);
 424
 425	return ret;
 426}
 427
 428static int csum_one_extent_buffer(struct extent_buffer *eb)
 
 
 
 429{
 
 430	struct btrfs_fs_info *fs_info = eb->fs_info;
 
 
 431	u8 result[BTRFS_CSUM_SIZE];
 432	int ret;
 433
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 434	ASSERT(memcmp_extent_buffer(eb, fs_info->fs_devices->metadata_uuid,
 435				    offsetof(struct btrfs_header, fsid),
 436				    BTRFS_FSID_SIZE) == 0);
 437	csum_tree_block(eb, result);
 438
 439	if (btrfs_header_level(eb))
 440		ret = btrfs_check_node(eb);
 441	else
 442		ret = btrfs_check_leaf_full(eb);
 443
 444	if (ret < 0) {
 445		btrfs_print_tree(eb, 0);
 
 
 
 
 
 
 
 
 446		btrfs_err(fs_info,
 447			"block=%llu write time tree block corruption detected",
 448			eb->start);
 449		WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
 450		return ret;
 451	}
 452	write_extent_buffer(eb, result, 0, fs_info->csum_size);
 
 453
 454	return 0;
 455}
 456
 457/* Checksum all dirty extent buffers in one bio_vec */
 458static int csum_dirty_subpage_buffers(struct btrfs_fs_info *fs_info,
 459				      struct bio_vec *bvec)
 460{
 461	struct page *page = bvec->bv_page;
 462	u64 bvec_start = page_offset(page) + bvec->bv_offset;
 463	u64 cur;
 464	int ret = 0;
 465
 466	for (cur = bvec_start; cur < bvec_start + bvec->bv_len;
 467	     cur += fs_info->nodesize) {
 468		struct extent_buffer *eb;
 469		bool uptodate;
 470
 471		eb = find_extent_buffer(fs_info, cur);
 472		uptodate = btrfs_subpage_test_uptodate(fs_info, page, cur,
 473						       fs_info->nodesize);
 474
 475		/* A dirty eb shouldn't disappear from buffer_radix */
 476		if (WARN_ON(!eb))
 477			return -EUCLEAN;
 478
 479		if (WARN_ON(cur != btrfs_header_bytenr(eb))) {
 480			free_extent_buffer(eb);
 481			return -EUCLEAN;
 482		}
 483		if (WARN_ON(!uptodate)) {
 484			free_extent_buffer(eb);
 485			return -EUCLEAN;
 486		}
 487
 488		ret = csum_one_extent_buffer(eb);
 489		free_extent_buffer(eb);
 490		if (ret < 0)
 491			return ret;
 492	}
 493	return ret;
 494}
 495
 496/*
 497 * Checksum a dirty tree block before IO.  This has extra checks to make sure
 498 * we only fill in the checksum field in the first page of a multi-page block.
 499 * For subpage extent buffers we need bvec to also read the offset in the page.
 500 */
 501static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct bio_vec *bvec)
 502{
 503	struct page *page = bvec->bv_page;
 504	u64 start = page_offset(page);
 505	u64 found_start;
 506	struct extent_buffer *eb;
 507
 508	if (fs_info->sectorsize < PAGE_SIZE)
 509		return csum_dirty_subpage_buffers(fs_info, bvec);
 510
 511	eb = (struct extent_buffer *)page->private;
 512	if (page != eb->pages[0])
 513		return 0;
 514
 515	found_start = btrfs_header_bytenr(eb);
 516
 517	if (test_bit(EXTENT_BUFFER_NO_CHECK, &eb->bflags)) {
 518		WARN_ON(found_start != 0);
 519		return 0;
 520	}
 521
 522	/*
 523	 * Please do not consolidate these warnings into a single if.
 524	 * It is useful to know what went wrong.
 525	 */
 526	if (WARN_ON(found_start != start))
 527		return -EUCLEAN;
 528	if (WARN_ON(!PageUptodate(page)))
 529		return -EUCLEAN;
 530
 531	return csum_one_extent_buffer(eb);
 532}
 533
 534static int check_tree_block_fsid(struct extent_buffer *eb)
 535{
 536	struct btrfs_fs_info *fs_info = eb->fs_info;
 537	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
 538	u8 fsid[BTRFS_FSID_SIZE];
 539	u8 *metadata_uuid;
 540
 541	read_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid),
 542			   BTRFS_FSID_SIZE);
 
 543	/*
 544	 * Checking the incompat flag is only valid for the current fs. For
 545	 * seed devices it's forbidden to have their uuid changed so reading
 546	 * ->fsid in this case is fine
 
 547	 */
 548	if (btrfs_fs_incompat(fs_info, METADATA_UUID))
 549		metadata_uuid = fs_devices->metadata_uuid;
 550	else
 551		metadata_uuid = fs_devices->fsid;
 552
 553	if (!memcmp(fsid, metadata_uuid, BTRFS_FSID_SIZE))
 554		return 0;
 555
 556	list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list)
 557		if (!memcmp(fsid, seed_devs->fsid, BTRFS_FSID_SIZE))
 558			return 0;
 559
 560	return 1;
 561}
 562
 563/* Do basic extent buffer checks at read time */
 564static int validate_extent_buffer(struct extent_buffer *eb)
 
 565{
 566	struct btrfs_fs_info *fs_info = eb->fs_info;
 567	u64 found_start;
 568	const u32 csum_size = fs_info->csum_size;
 569	u8 found_level;
 570	u8 result[BTRFS_CSUM_SIZE];
 571	const u8 *header_csum;
 572	int ret = 0;
 573
 
 
 574	found_start = btrfs_header_bytenr(eb);
 575	if (found_start != eb->start) {
 576		btrfs_err_rl(fs_info, "bad tree block start, want %llu have %llu",
 577			     eb->start, found_start);
 
 578		ret = -EIO;
 579		goto out;
 580	}
 581	if (check_tree_block_fsid(eb)) {
 582		btrfs_err_rl(fs_info, "bad fsid on block %llu",
 583			     eb->start);
 584		ret = -EIO;
 585		goto out;
 586	}
 587	found_level = btrfs_header_level(eb);
 588	if (found_level >= BTRFS_MAX_LEVEL) {
 589		btrfs_err(fs_info, "bad tree block level %d on %llu",
 590			  (int)btrfs_header_level(eb), eb->start);
 
 591		ret = -EIO;
 592		goto out;
 593	}
 594
 595	csum_tree_block(eb, result);
 596	header_csum = page_address(eb->pages[0]) +
 597		get_eb_offset_in_page(eb, offsetof(struct btrfs_header, csum));
 598
 599	if (memcmp(result, header_csum, csum_size) != 0) {
 600		btrfs_warn_rl(fs_info,
 601	"checksum verify failed on %llu wanted " CSUM_FMT " found " CSUM_FMT " level %d",
 602			      eb->start,
 603			      CSUM_FMT_VALUE(csum_size, header_csum),
 604			      CSUM_FMT_VALUE(csum_size, result),
 605			      btrfs_header_level(eb));
 606		ret = -EUCLEAN;
 607		goto out;
 608	}
 609
 610	/*
 611	 * If this is a leaf block and it is corrupt, set the corrupt bit so
 612	 * that we don't try and read the other copies of this block, just
 613	 * return -EIO.
 614	 */
 615	if (found_level == 0 && btrfs_check_leaf_full(eb)) {
 616		set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 617		ret = -EIO;
 618	}
 619
 620	if (found_level > 0 && btrfs_check_node(eb))
 621		ret = -EIO;
 622
 623	if (!ret)
 624		set_extent_buffer_uptodate(eb);
 625	else
 626		btrfs_err(fs_info,
 627			  "block=%llu read time tree block corruption detected",
 628			  eb->start);
 629out:
 630	return ret;
 631}
 632
 633static int validate_subpage_buffer(struct page *page, u64 start, u64 end,
 634				   int mirror)
 635{
 636	struct btrfs_fs_info *fs_info = btrfs_sb(page->mapping->host->i_sb);
 637	struct extent_buffer *eb;
 638	bool reads_done;
 639	int ret = 0;
 640
 641	/*
 642	 * We don't allow bio merge for subpage metadata read, so we should
 643	 * only get one eb for each endio hook.
 644	 */
 645	ASSERT(end == start + fs_info->nodesize - 1);
 646	ASSERT(PagePrivate(page));
 647
 648	eb = find_extent_buffer(fs_info, start);
 649	/*
 650	 * When we are reading one tree block, eb must have been inserted into
 651	 * the radix tree. If not, something is wrong.
 652	 */
 653	ASSERT(eb);
 654
 655	reads_done = atomic_dec_and_test(&eb->io_pages);
 656	/* Subpage read must finish in page read */
 657	ASSERT(reads_done);
 658
 659	eb->read_mirror = mirror;
 660	if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
 661		ret = -EIO;
 662		goto err;
 663	}
 664	ret = validate_extent_buffer(eb);
 665	if (ret < 0)
 666		goto err;
 667
 668	if (test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
 669		btree_readahead_hook(eb, ret);
 670
 671	set_extent_buffer_uptodate(eb);
 672
 673	free_extent_buffer(eb);
 674	return ret;
 675err:
 676	/*
 677	 * end_bio_extent_readpage decrements io_pages in case of error,
 678	 * make sure it has something to decrement.
 679	 */
 680	atomic_inc(&eb->io_pages);
 681	clear_extent_buffer_uptodate(eb);
 682	free_extent_buffer(eb);
 683	return ret;
 684}
 685
 686int btrfs_validate_metadata_buffer(struct btrfs_io_bio *io_bio,
 687				   struct page *page, u64 start, u64 end,
 688				   int mirror)
 689{
 690	struct extent_buffer *eb;
 691	int ret = 0;
 692	int reads_done;
 693
 694	ASSERT(page->private);
 695
 696	if (btrfs_sb(page->mapping->host->i_sb)->sectorsize < PAGE_SIZE)
 697		return validate_subpage_buffer(page, start, end, mirror);
 698
 699	eb = (struct extent_buffer *)page->private;
 700
 701	/*
 702	 * The pending IO might have been the only thing that kept this buffer
 703	 * in memory.  Make sure we have a ref for all this other checks
 704	 */
 705	atomic_inc(&eb->refs);
 706
 707	reads_done = atomic_dec_and_test(&eb->io_pages);
 708	if (!reads_done)
 709		goto err;
 710
 711	eb->read_mirror = mirror;
 712	if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
 713		ret = -EIO;
 714		goto err;
 715	}
 716	ret = validate_extent_buffer(eb);
 717err:
 718	if (reads_done &&
 719	    test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
 720		btree_readahead_hook(eb, ret);
 721
 722	if (ret) {
 723		/*
 724		 * our io error hook is going to dec the io pages
 725		 * again, we have to make sure it has something
 726		 * to decrement
 727		 */
 728		atomic_inc(&eb->io_pages);
 729		clear_extent_buffer_uptodate(eb);
 730	}
 731	free_extent_buffer(eb);
 732
 733	return ret;
 734}
 735
 736static void end_workqueue_bio(struct bio *bio)
 737{
 738	struct btrfs_end_io_wq *end_io_wq = bio->bi_private;
 739	struct btrfs_fs_info *fs_info;
 740	struct btrfs_workqueue *wq;
 741
 742	fs_info = end_io_wq->info;
 743	end_io_wq->status = bio->bi_status;
 744
 745	if (btrfs_op(bio) == BTRFS_MAP_WRITE) {
 746		if (end_io_wq->metadata == BTRFS_WQ_ENDIO_METADATA)
 747			wq = fs_info->endio_meta_write_workers;
 748		else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_FREE_SPACE)
 749			wq = fs_info->endio_freespace_worker;
 750		else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56)
 751			wq = fs_info->endio_raid56_workers;
 752		else
 753			wq = fs_info->endio_write_workers;
 754	} else {
 755		if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56)
 756			wq = fs_info->endio_raid56_workers;
 757		else if (end_io_wq->metadata)
 758			wq = fs_info->endio_meta_workers;
 759		else
 760			wq = fs_info->endio_workers;
 
 
 
 
 761	}
 762
 763	btrfs_init_work(&end_io_wq->work, end_workqueue_fn, NULL, NULL);
 764	btrfs_queue_work(wq, &end_io_wq->work);
 765}
 766
 767blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
 768			enum btrfs_wq_endio_type metadata)
 769{
 770	struct btrfs_end_io_wq *end_io_wq;
 771
 772	end_io_wq = kmem_cache_alloc(btrfs_end_io_wq_cache, GFP_NOFS);
 773	if (!end_io_wq)
 774		return BLK_STS_RESOURCE;
 775
 776	end_io_wq->private = bio->bi_private;
 777	end_io_wq->end_io = bio->bi_end_io;
 778	end_io_wq->info = info;
 779	end_io_wq->status = 0;
 780	end_io_wq->bio = bio;
 781	end_io_wq->metadata = metadata;
 782
 783	bio->bi_private = end_io_wq;
 784	bio->bi_end_io = end_workqueue_bio;
 785	return 0;
 786}
 787
 788static void run_one_async_start(struct btrfs_work *work)
 789{
 790	struct async_submit_bio *async;
 791	blk_status_t ret;
 792
 793	async = container_of(work, struct  async_submit_bio, work);
 794	ret = async->submit_bio_start(async->inode, async->bio,
 795				      async->dio_file_offset);
 796	if (ret)
 797		async->status = ret;
 798}
 799
 800/*
 801 * In order to insert checksums into the metadata in large chunks, we wait
 802 * until bio submission time.   All the pages in the bio are checksummed and
 803 * sums are attached onto the ordered extent record.
 804 *
 805 * At IO completion time the csums attached on the ordered extent record are
 806 * inserted into the tree.
 807 */
 808static void run_one_async_done(struct btrfs_work *work)
 809{
 810	struct async_submit_bio *async;
 811	struct inode *inode;
 812	blk_status_t ret;
 813
 814	async = container_of(work, struct  async_submit_bio, work);
 815	inode = async->inode;
 816
 817	/* If an error occurred we just want to clean up the bio and move on */
 818	if (async->status) {
 819		async->bio->bi_status = async->status;
 820		bio_endio(async->bio);
 821		return;
 822	}
 823
 824	/*
 825	 * All of the bios that pass through here are from async helpers.
 826	 * Use REQ_CGROUP_PUNT to issue them from the owning cgroup's context.
 827	 * This changes nothing when cgroups aren't in use.
 828	 */
 829	async->bio->bi_opf |= REQ_CGROUP_PUNT;
 830	ret = btrfs_map_bio(btrfs_sb(inode->i_sb), async->bio, async->mirror_num);
 831	if (ret) {
 832		async->bio->bi_status = ret;
 833		bio_endio(async->bio);
 834	}
 835}
 836
 837static void run_one_async_free(struct btrfs_work *work)
 838{
 839	struct async_submit_bio *async;
 840
 841	async = container_of(work, struct  async_submit_bio, work);
 842	kfree(async);
 843}
 844
 845blk_status_t btrfs_wq_submit_bio(struct inode *inode, struct bio *bio,
 846				 int mirror_num, unsigned long bio_flags,
 847				 u64 dio_file_offset,
 848				 extent_submit_bio_start_t *submit_bio_start)
 849{
 850	struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
 851	struct async_submit_bio *async;
 852
 853	async = kmalloc(sizeof(*async), GFP_NOFS);
 854	if (!async)
 855		return BLK_STS_RESOURCE;
 856
 857	async->inode = inode;
 858	async->bio = bio;
 859	async->mirror_num = mirror_num;
 860	async->submit_bio_start = submit_bio_start;
 861
 862	btrfs_init_work(&async->work, run_one_async_start, run_one_async_done,
 863			run_one_async_free);
 864
 865	async->dio_file_offset = dio_file_offset;
 866
 867	async->status = 0;
 868
 869	if (op_is_sync(bio->bi_opf))
 870		btrfs_set_work_high_priority(&async->work);
 871
 872	btrfs_queue_work(fs_info->workers, &async->work);
 873	return 0;
 874}
 875
 876static blk_status_t btree_csum_one_bio(struct bio *bio)
 877{
 878	struct bio_vec *bvec;
 879	struct btrfs_root *root;
 880	int ret = 0;
 881	struct bvec_iter_all iter_all;
 882
 883	ASSERT(!bio_flagged(bio, BIO_CLONED));
 884	bio_for_each_segment_all(bvec, bio, iter_all) {
 885		root = BTRFS_I(bvec->bv_page->mapping->host)->root;
 886		ret = csum_dirty_buffer(root->fs_info, bvec);
 887		if (ret)
 888			break;
 889	}
 890
 891	return errno_to_blk_status(ret);
 892}
 893
 894static blk_status_t btree_submit_bio_start(struct inode *inode, struct bio *bio,
 895					   u64 dio_file_offset)
 896{
 897	/*
 898	 * when we're called for a write, we're already in the async
 899	 * submission context.  Just jump into btrfs_map_bio
 900	 */
 901	return btree_csum_one_bio(bio);
 902}
 903
 904static bool should_async_write(struct btrfs_fs_info *fs_info,
 905			     struct btrfs_inode *bi)
 906{
 907	if (btrfs_is_zoned(fs_info))
 908		return false;
 909	if (atomic_read(&bi->sync_writers))
 910		return false;
 911	if (test_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags))
 912		return false;
 913	return true;
 914}
 915
 916blk_status_t btrfs_submit_metadata_bio(struct inode *inode, struct bio *bio,
 917				       int mirror_num, unsigned long bio_flags)
 918{
 919	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 920	blk_status_t ret;
 921
 922	if (btrfs_op(bio) != BTRFS_MAP_WRITE) {
 923		/*
 924		 * called for a read, do the setup so that checksum validation
 925		 * can happen in the async kernel threads
 926		 */
 927		ret = btrfs_bio_wq_end_io(fs_info, bio,
 928					  BTRFS_WQ_ENDIO_METADATA);
 929		if (ret)
 930			goto out_w_error;
 931		ret = btrfs_map_bio(fs_info, bio, mirror_num);
 932	} else if (!should_async_write(fs_info, BTRFS_I(inode))) {
 933		ret = btree_csum_one_bio(bio);
 934		if (ret)
 935			goto out_w_error;
 936		ret = btrfs_map_bio(fs_info, bio, mirror_num);
 937	} else {
 938		/*
 939		 * kthread helpers are used to submit writes so that
 940		 * checksumming can happen in parallel across all CPUs
 941		 */
 942		ret = btrfs_wq_submit_bio(inode, bio, mirror_num, 0,
 943					  0, btree_submit_bio_start);
 944	}
 945
 946	if (ret)
 947		goto out_w_error;
 948	return 0;
 949
 950out_w_error:
 951	bio->bi_status = ret;
 952	bio_endio(bio);
 953	return ret;
 954}
 955
 956#ifdef CONFIG_MIGRATION
 957static int btree_migratepage(struct address_space *mapping,
 958			struct page *newpage, struct page *page,
 959			enum migrate_mode mode)
 960{
 961	/*
 962	 * we can't safely write a btree page from here,
 963	 * we haven't done the locking hook
 964	 */
 965	if (PageDirty(page))
 966		return -EAGAIN;
 967	/*
 968	 * Buffers may be managed in a filesystem specific way.
 969	 * We must have no buffers or drop them.
 970	 */
 971	if (page_has_private(page) &&
 972	    !try_to_release_page(page, GFP_KERNEL))
 973		return -EAGAIN;
 974	return migrate_page(mapping, newpage, page, mode);
 975}
 
 
 976#endif
 977
 978
 979static int btree_writepages(struct address_space *mapping,
 980			    struct writeback_control *wbc)
 981{
 982	struct btrfs_fs_info *fs_info;
 983	int ret;
 984
 985	if (wbc->sync_mode == WB_SYNC_NONE) {
 986
 987		if (wbc->for_kupdate)
 988			return 0;
 989
 990		fs_info = BTRFS_I(mapping->host)->root->fs_info;
 991		/* this is a bit racy, but that's ok */
 992		ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
 993					     BTRFS_DIRTY_METADATA_THRESH,
 994					     fs_info->dirty_metadata_batch);
 995		if (ret < 0)
 996			return 0;
 997	}
 998	return btree_write_cache_pages(mapping, wbc);
 999}
1000
1001static int btree_releasepage(struct page *page, gfp_t gfp_flags)
1002{
1003	if (PageWriteback(page) || PageDirty(page))
1004		return 0;
1005
1006	return try_release_extent_buffer(page);
1007}
1008
1009static void btree_invalidatepage(struct page *page, unsigned int offset,
1010				 unsigned int length)
1011{
1012	struct extent_io_tree *tree;
1013	tree = &BTRFS_I(page->mapping->host)->io_tree;
1014	extent_invalidatepage(tree, page, offset);
1015	btree_releasepage(page, GFP_NOFS);
1016	if (PagePrivate(page)) {
1017		btrfs_warn(BTRFS_I(page->mapping->host)->root->fs_info,
1018			   "page private not zero on page %llu",
1019			   (unsigned long long)page_offset(page));
1020		detach_page_private(page);
1021	}
1022}
1023
1024static int btree_set_page_dirty(struct page *page)
 
 
1025{
1026#ifdef DEBUG
1027	struct btrfs_fs_info *fs_info = btrfs_sb(page->mapping->host->i_sb);
1028	struct btrfs_subpage *subpage;
1029	struct extent_buffer *eb;
1030	int cur_bit = 0;
1031	u64 page_start = page_offset(page);
1032
1033	if (fs_info->sectorsize == PAGE_SIZE) {
1034		BUG_ON(!PagePrivate(page));
1035		eb = (struct extent_buffer *)page->private;
1036		BUG_ON(!eb);
1037		BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
1038		BUG_ON(!atomic_read(&eb->refs));
1039		btrfs_assert_tree_locked(eb);
1040		return __set_page_dirty_nobuffers(page);
1041	}
1042	ASSERT(PagePrivate(page) && page->private);
1043	subpage = (struct btrfs_subpage *)page->private;
1044
1045	ASSERT(subpage->dirty_bitmap);
1046	while (cur_bit < BTRFS_SUBPAGE_BITMAP_SIZE) {
 
 
 
 
1047		unsigned long flags;
1048		u64 cur;
1049		u16 tmp = (1 << cur_bit);
1050
1051		spin_lock_irqsave(&subpage->lock, flags);
1052		if (!(tmp & subpage->dirty_bitmap)) {
1053			spin_unlock_irqrestore(&subpage->lock, flags);
1054			cur_bit++;
1055			continue;
1056		}
1057		spin_unlock_irqrestore(&subpage->lock, flags);
1058		cur = page_start + cur_bit * fs_info->sectorsize;
1059
1060		eb = find_extent_buffer(fs_info, cur);
1061		ASSERT(eb);
1062		ASSERT(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
1063		ASSERT(atomic_read(&eb->refs));
1064		btrfs_assert_tree_locked(eb);
1065		free_extent_buffer(eb);
1066
1067		cur_bit += (fs_info->nodesize >> fs_info->sectorsize_bits);
1068	}
 
 
 
 
1069#endif
1070	return __set_page_dirty_nobuffers(page);
1071}
1072
1073static const struct address_space_operations btree_aops = {
1074	.writepages	= btree_writepages,
1075	.releasepage	= btree_releasepage,
1076	.invalidatepage = btree_invalidatepage,
1077#ifdef CONFIG_MIGRATION
1078	.migratepage	= btree_migratepage,
1079#endif
1080	.set_page_dirty = btree_set_page_dirty,
1081};
1082
1083struct extent_buffer *btrfs_find_create_tree_block(
1084						struct btrfs_fs_info *fs_info,
1085						u64 bytenr, u64 owner_root,
1086						int level)
1087{
1088	if (btrfs_is_testing(fs_info))
1089		return alloc_test_extent_buffer(fs_info, bytenr);
1090	return alloc_extent_buffer(fs_info, bytenr, owner_root, level);
1091}
1092
1093/*
1094 * Read tree block at logical address @bytenr and do variant basic but critical
1095 * verification.
1096 *
1097 * @owner_root:		the objectid of the root owner for this block.
1098 * @parent_transid:	expected transid of this tree block, skip check if 0
1099 * @level:		expected level, mandatory check
1100 * @first_key:		expected key in slot 0, skip check if NULL
1101 */
1102struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
1103				      u64 owner_root, u64 parent_transid,
1104				      int level, struct btrfs_key *first_key)
1105{
1106	struct extent_buffer *buf = NULL;
1107	int ret;
1108
1109	buf = btrfs_find_create_tree_block(fs_info, bytenr, owner_root, level);
 
 
 
1110	if (IS_ERR(buf))
1111		return buf;
1112
1113	ret = btree_read_extent_buffer_pages(buf, parent_transid,
1114					     level, first_key);
1115	if (ret) {
1116		free_extent_buffer_stale(buf);
1117		return ERR_PTR(ret);
1118	}
 
 
 
 
1119	return buf;
1120
1121}
1122
1123void btrfs_clean_tree_block(struct extent_buffer *buf)
1124{
1125	struct btrfs_fs_info *fs_info = buf->fs_info;
1126	if (btrfs_header_generation(buf) ==
1127	    fs_info->running_transaction->transid) {
1128		btrfs_assert_tree_locked(buf);
1129
1130		if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
1131			percpu_counter_add_batch(&fs_info->dirty_metadata_bytes,
1132						 -buf->len,
1133						 fs_info->dirty_metadata_batch);
1134			clear_extent_buffer_dirty(buf);
1135		}
1136	}
1137}
1138
1139static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
1140			 u64 objectid)
1141{
1142	bool dummy = test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state);
 
 
 
 
1143	root->fs_info = fs_info;
 
1144	root->node = NULL;
1145	root->commit_root = NULL;
1146	root->state = 0;
1147	root->orphan_cleanup_state = 0;
1148
1149	root->last_trans = 0;
1150	root->free_objectid = 0;
1151	root->nr_delalloc_inodes = 0;
1152	root->nr_ordered_extents = 0;
1153	root->inode_tree = RB_ROOT;
1154	INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
1155	root->block_rsv = NULL;
 
 
1156
1157	INIT_LIST_HEAD(&root->dirty_list);
1158	INIT_LIST_HEAD(&root->root_list);
1159	INIT_LIST_HEAD(&root->delalloc_inodes);
1160	INIT_LIST_HEAD(&root->delalloc_root);
1161	INIT_LIST_HEAD(&root->ordered_extents);
1162	INIT_LIST_HEAD(&root->ordered_root);
1163	INIT_LIST_HEAD(&root->reloc_dirty_list);
1164	INIT_LIST_HEAD(&root->logged_list[0]);
1165	INIT_LIST_HEAD(&root->logged_list[1]);
1166	spin_lock_init(&root->inode_lock);
1167	spin_lock_init(&root->delalloc_lock);
1168	spin_lock_init(&root->ordered_extent_lock);
1169	spin_lock_init(&root->accounting_lock);
1170	spin_lock_init(&root->log_extents_lock[0]);
1171	spin_lock_init(&root->log_extents_lock[1]);
1172	spin_lock_init(&root->qgroup_meta_rsv_lock);
1173	mutex_init(&root->objectid_mutex);
1174	mutex_init(&root->log_mutex);
1175	mutex_init(&root->ordered_extent_mutex);
1176	mutex_init(&root->delalloc_mutex);
1177	init_waitqueue_head(&root->qgroup_flush_wait);
1178	init_waitqueue_head(&root->log_writer_wait);
1179	init_waitqueue_head(&root->log_commit_wait[0]);
1180	init_waitqueue_head(&root->log_commit_wait[1]);
1181	INIT_LIST_HEAD(&root->log_ctxs[0]);
1182	INIT_LIST_HEAD(&root->log_ctxs[1]);
1183	atomic_set(&root->log_commit[0], 0);
1184	atomic_set(&root->log_commit[1], 0);
1185	atomic_set(&root->log_writers, 0);
1186	atomic_set(&root->log_batch, 0);
1187	refcount_set(&root->refs, 1);
1188	atomic_set(&root->snapshot_force_cow, 0);
1189	atomic_set(&root->nr_swapfiles, 0);
1190	root->log_transid = 0;
1191	root->log_transid_committed = -1;
1192	root->last_log_commit = 0;
 
1193	if (!dummy) {
1194		extent_io_tree_init(fs_info, &root->dirty_log_pages,
1195				    IO_TREE_ROOT_DIRTY_LOG_PAGES, NULL);
1196		extent_io_tree_init(fs_info, &root->log_csum_range,
1197				    IO_TREE_LOG_CSUM_RANGE, NULL);
1198	}
1199
1200	memset(&root->root_key, 0, sizeof(root->root_key));
1201	memset(&root->root_item, 0, sizeof(root->root_item));
1202	memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
1203	root->root_key.objectid = objectid;
1204	root->anon_dev = 0;
1205
1206	spin_lock_init(&root->root_item_lock);
1207	btrfs_qgroup_init_swapped_blocks(&root->swapped_blocks);
1208#ifdef CONFIG_BTRFS_DEBUG
1209	INIT_LIST_HEAD(&root->leak_list);
1210	spin_lock(&fs_info->fs_roots_radix_lock);
1211	list_add_tail(&root->leak_list, &fs_info->allocated_roots);
1212	spin_unlock(&fs_info->fs_roots_radix_lock);
1213#endif
1214}
1215
1216static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info,
1217					   u64 objectid, gfp_t flags)
1218{
1219	struct btrfs_root *root = kzalloc(sizeof(*root), flags);
1220	if (root)
1221		__setup_root(root, fs_info, objectid);
1222	return root;
1223}
1224
1225#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
1226/* Should only be used by the testing infrastructure */
1227struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info)
1228{
1229	struct btrfs_root *root;
1230
1231	if (!fs_info)
1232		return ERR_PTR(-EINVAL);
1233
1234	root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID, GFP_KERNEL);
1235	if (!root)
1236		return ERR_PTR(-ENOMEM);
1237
1238	/* We don't use the stripesize in selftest, set it as sectorsize */
1239	root->alloc_bytenr = 0;
1240
1241	return root;
1242}
1243#endif
1244
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1245struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
1246				     u64 objectid)
1247{
1248	struct btrfs_fs_info *fs_info = trans->fs_info;
1249	struct extent_buffer *leaf;
1250	struct btrfs_root *tree_root = fs_info->tree_root;
1251	struct btrfs_root *root;
1252	struct btrfs_key key;
1253	unsigned int nofs_flag;
1254	int ret = 0;
1255
1256	/*
1257	 * We're holding a transaction handle, so use a NOFS memory allocation
1258	 * context to avoid deadlock if reclaim happens.
1259	 */
1260	nofs_flag = memalloc_nofs_save();
1261	root = btrfs_alloc_root(fs_info, objectid, GFP_KERNEL);
1262	memalloc_nofs_restore(nofs_flag);
1263	if (!root)
1264		return ERR_PTR(-ENOMEM);
1265
1266	root->root_key.objectid = objectid;
1267	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1268	root->root_key.offset = 0;
1269
1270	leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0,
1271				      BTRFS_NESTING_NORMAL);
1272	if (IS_ERR(leaf)) {
1273		ret = PTR_ERR(leaf);
1274		leaf = NULL;
1275		goto fail_unlock;
1276	}
1277
1278	root->node = leaf;
1279	btrfs_mark_buffer_dirty(leaf);
1280
1281	root->commit_root = btrfs_root_node(root);
1282	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
1283
1284	btrfs_set_root_flags(&root->root_item, 0);
1285	btrfs_set_root_limit(&root->root_item, 0);
1286	btrfs_set_root_bytenr(&root->root_item, leaf->start);
1287	btrfs_set_root_generation(&root->root_item, trans->transid);
1288	btrfs_set_root_level(&root->root_item, 0);
1289	btrfs_set_root_refs(&root->root_item, 1);
1290	btrfs_set_root_used(&root->root_item, leaf->len);
1291	btrfs_set_root_last_snapshot(&root->root_item, 0);
1292	btrfs_set_root_dirid(&root->root_item, 0);
1293	if (is_fstree(objectid))
1294		generate_random_guid(root->root_item.uuid);
1295	else
1296		export_guid(root->root_item.uuid, &guid_null);
1297	btrfs_set_root_drop_level(&root->root_item, 0);
1298
1299	btrfs_tree_unlock(leaf);
1300
1301	key.objectid = objectid;
1302	key.type = BTRFS_ROOT_ITEM_KEY;
1303	key.offset = 0;
1304	ret = btrfs_insert_root(trans, tree_root, &key, &root->root_item);
1305	if (ret)
1306		goto fail;
1307
1308	return root;
1309
1310fail_unlock:
1311	if (leaf)
1312		btrfs_tree_unlock(leaf);
1313fail:
1314	btrfs_put_root(root);
1315
1316	return ERR_PTR(ret);
1317}
1318
1319static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
1320					 struct btrfs_fs_info *fs_info)
1321{
1322	struct btrfs_root *root;
1323
1324	root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID, GFP_NOFS);
1325	if (!root)
1326		return ERR_PTR(-ENOMEM);
1327
1328	root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1329	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1330	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
1331
1332	return root;
1333}
1334
1335int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
1336			      struct btrfs_root *root)
1337{
1338	struct extent_buffer *leaf;
1339
1340	/*
1341	 * DON'T set SHAREABLE bit for log trees.
1342	 *
1343	 * Log trees are not exposed to user space thus can't be snapshotted,
1344	 * and they go away before a real commit is actually done.
1345	 *
1346	 * They do store pointers to file data extents, and those reference
1347	 * counts still get updated (along with back refs to the log tree).
1348	 */
1349
1350	leaf = btrfs_alloc_tree_block(trans, root, 0, BTRFS_TREE_LOG_OBJECTID,
1351			NULL, 0, 0, 0, BTRFS_NESTING_NORMAL);
1352	if (IS_ERR(leaf))
1353		return PTR_ERR(leaf);
1354
1355	root->node = leaf;
1356
1357	btrfs_mark_buffer_dirty(root->node);
1358	btrfs_tree_unlock(root->node);
1359
1360	return 0;
1361}
1362
1363int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1364			     struct btrfs_fs_info *fs_info)
1365{
1366	struct btrfs_root *log_root;
1367
1368	log_root = alloc_log_tree(trans, fs_info);
1369	if (IS_ERR(log_root))
1370		return PTR_ERR(log_root);
1371
1372	if (!btrfs_is_zoned(fs_info)) {
1373		int ret = btrfs_alloc_log_tree_node(trans, log_root);
1374
1375		if (ret) {
1376			btrfs_put_root(log_root);
1377			return ret;
1378		}
1379	}
1380
1381	WARN_ON(fs_info->log_root_tree);
1382	fs_info->log_root_tree = log_root;
1383	return 0;
1384}
1385
1386int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1387		       struct btrfs_root *root)
1388{
1389	struct btrfs_fs_info *fs_info = root->fs_info;
1390	struct btrfs_root *log_root;
1391	struct btrfs_inode_item *inode_item;
1392	int ret;
1393
1394	log_root = alloc_log_tree(trans, fs_info);
1395	if (IS_ERR(log_root))
1396		return PTR_ERR(log_root);
1397
1398	ret = btrfs_alloc_log_tree_node(trans, log_root);
1399	if (ret) {
1400		btrfs_put_root(log_root);
1401		return ret;
1402	}
1403
1404	log_root->last_trans = trans->transid;
1405	log_root->root_key.offset = root->root_key.objectid;
1406
1407	inode_item = &log_root->root_item.inode;
1408	btrfs_set_stack_inode_generation(inode_item, 1);
1409	btrfs_set_stack_inode_size(inode_item, 3);
1410	btrfs_set_stack_inode_nlink(inode_item, 1);
1411	btrfs_set_stack_inode_nbytes(inode_item,
1412				     fs_info->nodesize);
1413	btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
1414
1415	btrfs_set_root_node(&log_root->root_item, log_root->node);
1416
1417	WARN_ON(root->log_root);
1418	root->log_root = log_root;
1419	root->log_transid = 0;
1420	root->log_transid_committed = -1;
1421	root->last_log_commit = 0;
1422	return 0;
1423}
1424
1425static struct btrfs_root *read_tree_root_path(struct btrfs_root *tree_root,
1426					      struct btrfs_path *path,
1427					      struct btrfs_key *key)
1428{
1429	struct btrfs_root *root;
 
1430	struct btrfs_fs_info *fs_info = tree_root->fs_info;
1431	u64 generation;
1432	int ret;
1433	int level;
1434
1435	root = btrfs_alloc_root(fs_info, key->objectid, GFP_NOFS);
1436	if (!root)
1437		return ERR_PTR(-ENOMEM);
1438
1439	ret = btrfs_find_root(tree_root, key, path,
1440			      &root->root_item, &root->root_key);
1441	if (ret) {
1442		if (ret > 0)
1443			ret = -ENOENT;
1444		goto fail;
1445	}
1446
1447	generation = btrfs_root_generation(&root->root_item);
1448	level = btrfs_root_level(&root->root_item);
1449	root->node = read_tree_block(fs_info,
1450				     btrfs_root_bytenr(&root->root_item),
1451				     key->objectid, generation, level, NULL);
 
 
1452	if (IS_ERR(root->node)) {
1453		ret = PTR_ERR(root->node);
1454		root->node = NULL;
1455		goto fail;
1456	} else if (!btrfs_buffer_uptodate(root->node, generation, 0)) {
 
1457		ret = -EIO;
1458		goto fail;
1459	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1460	root->commit_root = btrfs_root_node(root);
1461	return root;
1462fail:
1463	btrfs_put_root(root);
1464	return ERR_PTR(ret);
1465}
1466
1467struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
1468					struct btrfs_key *key)
1469{
1470	struct btrfs_root *root;
1471	struct btrfs_path *path;
1472
1473	path = btrfs_alloc_path();
1474	if (!path)
1475		return ERR_PTR(-ENOMEM);
1476	root = read_tree_root_path(tree_root, path, key);
1477	btrfs_free_path(path);
1478
1479	return root;
1480}
1481
1482/*
1483 * Initialize subvolume root in-memory structure
1484 *
1485 * @anon_dev:	anonymous device to attach to the root, if zero, allocate new
1486 */
1487static int btrfs_init_fs_root(struct btrfs_root *root, dev_t anon_dev)
1488{
1489	int ret;
1490	unsigned int nofs_flag;
1491
1492	/*
1493	 * We might be called under a transaction (e.g. indirect backref
1494	 * resolution) which could deadlock if it triggers memory reclaim
1495	 */
1496	nofs_flag = memalloc_nofs_save();
1497	ret = btrfs_drew_lock_init(&root->snapshot_lock);
1498	memalloc_nofs_restore(nofs_flag);
1499	if (ret)
1500		goto fail;
1501
1502	if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID &&
1503	    root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID) {
 
1504		set_bit(BTRFS_ROOT_SHAREABLE, &root->state);
1505		btrfs_check_and_init_root_item(&root->root_item);
1506	}
1507
1508	/*
1509	 * Don't assign anonymous block device to roots that are not exposed to
1510	 * userspace, the id pool is limited to 1M
1511	 */
1512	if (is_fstree(root->root_key.objectid) &&
1513	    btrfs_root_refs(&root->root_item) > 0) {
1514		if (!anon_dev) {
1515			ret = get_anon_bdev(&root->anon_dev);
1516			if (ret)
1517				goto fail;
1518		} else {
1519			root->anon_dev = anon_dev;
1520		}
1521	}
1522
1523	mutex_lock(&root->objectid_mutex);
1524	ret = btrfs_init_root_free_objectid(root);
1525	if (ret) {
1526		mutex_unlock(&root->objectid_mutex);
1527		goto fail;
1528	}
1529
1530	ASSERT(root->free_objectid <= BTRFS_LAST_FREE_OBJECTID);
1531
1532	mutex_unlock(&root->objectid_mutex);
1533
1534	return 0;
1535fail:
1536	/* The caller is responsible to call btrfs_free_fs_root */
1537	return ret;
1538}
1539
1540static struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
1541					       u64 root_id)
1542{
1543	struct btrfs_root *root;
1544
1545	spin_lock(&fs_info->fs_roots_radix_lock);
1546	root = radix_tree_lookup(&fs_info->fs_roots_radix,
1547				 (unsigned long)root_id);
1548	if (root)
1549		root = btrfs_grab_root(root);
1550	spin_unlock(&fs_info->fs_roots_radix_lock);
1551	return root;
1552}
1553
1554static struct btrfs_root *btrfs_get_global_root(struct btrfs_fs_info *fs_info,
1555						u64 objectid)
1556{
1557	if (objectid == BTRFS_ROOT_TREE_OBJECTID)
 
 
 
 
 
 
 
1558		return btrfs_grab_root(fs_info->tree_root);
1559	if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
1560		return btrfs_grab_root(fs_info->extent_root);
1561	if (objectid == BTRFS_CHUNK_TREE_OBJECTID)
1562		return btrfs_grab_root(fs_info->chunk_root);
1563	if (objectid == BTRFS_DEV_TREE_OBJECTID)
1564		return btrfs_grab_root(fs_info->dev_root);
1565	if (objectid == BTRFS_CSUM_TREE_OBJECTID)
1566		return btrfs_grab_root(fs_info->csum_root);
1567	if (objectid == BTRFS_QUOTA_TREE_OBJECTID)
1568		return btrfs_grab_root(fs_info->quota_root) ?
1569			fs_info->quota_root : ERR_PTR(-ENOENT);
1570	if (objectid == BTRFS_UUID_TREE_OBJECTID)
1571		return btrfs_grab_root(fs_info->uuid_root) ?
1572			fs_info->uuid_root : ERR_PTR(-ENOENT);
1573	if (objectid == BTRFS_FREE_SPACE_TREE_OBJECTID)
1574		return btrfs_grab_root(fs_info->free_space_root) ?
1575			fs_info->free_space_root : ERR_PTR(-ENOENT);
1576	return NULL;
 
 
 
1577}
1578
1579int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
1580			 struct btrfs_root *root)
1581{
1582	int ret;
1583
1584	ret = radix_tree_preload(GFP_NOFS);
1585	if (ret)
1586		return ret;
1587
1588	spin_lock(&fs_info->fs_roots_radix_lock);
1589	ret = radix_tree_insert(&fs_info->fs_roots_radix,
1590				(unsigned long)root->root_key.objectid,
1591				root);
1592	if (ret == 0) {
1593		btrfs_grab_root(root);
1594		set_bit(BTRFS_ROOT_IN_RADIX, &root->state);
1595	}
1596	spin_unlock(&fs_info->fs_roots_radix_lock);
1597	radix_tree_preload_end();
1598
1599	return ret;
1600}
1601
1602void btrfs_check_leaked_roots(struct btrfs_fs_info *fs_info)
1603{
1604#ifdef CONFIG_BTRFS_DEBUG
1605	struct btrfs_root *root;
1606
1607	while (!list_empty(&fs_info->allocated_roots)) {
1608		char buf[BTRFS_ROOT_NAME_BUF_LEN];
1609
1610		root = list_first_entry(&fs_info->allocated_roots,
1611					struct btrfs_root, leak_list);
1612		btrfs_err(fs_info, "leaked root %s refcount %d",
1613			  btrfs_root_name(&root->root_key, buf),
1614			  refcount_read(&root->refs));
1615		while (refcount_read(&root->refs) > 1)
1616			btrfs_put_root(root);
1617		btrfs_put_root(root);
1618	}
1619#endif
1620}
1621
 
 
 
 
 
 
 
 
 
 
 
 
1622void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
1623{
1624	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
1625	percpu_counter_destroy(&fs_info->delalloc_bytes);
1626	percpu_counter_destroy(&fs_info->ordered_bytes);
1627	percpu_counter_destroy(&fs_info->dev_replace.bio_counter);
1628	btrfs_free_csum_hash(fs_info);
1629	btrfs_free_stripe_hash_table(fs_info);
1630	btrfs_free_ref_cache(fs_info);
1631	kfree(fs_info->balance_ctl);
1632	kfree(fs_info->delayed_root);
1633	btrfs_put_root(fs_info->extent_root);
1634	btrfs_put_root(fs_info->tree_root);
1635	btrfs_put_root(fs_info->chunk_root);
1636	btrfs_put_root(fs_info->dev_root);
1637	btrfs_put_root(fs_info->csum_root);
1638	btrfs_put_root(fs_info->quota_root);
1639	btrfs_put_root(fs_info->uuid_root);
1640	btrfs_put_root(fs_info->free_space_root);
1641	btrfs_put_root(fs_info->fs_root);
1642	btrfs_put_root(fs_info->data_reloc_root);
 
 
1643	btrfs_check_leaked_roots(fs_info);
1644	btrfs_extent_buffer_leak_debug_check(fs_info);
1645	kfree(fs_info->super_copy);
1646	kfree(fs_info->super_for_commit);
 
1647	kvfree(fs_info);
1648}
1649
1650
1651/*
1652 * Get an in-memory reference of a root structure.
1653 *
1654 * For essential trees like root/extent tree, we grab it from fs_info directly.
1655 * For subvolume trees, we check the cached filesystem roots first. If not
1656 * found, then read it from disk and add it to cached fs roots.
1657 *
1658 * Caller should release the root by calling btrfs_put_root() after the usage.
1659 *
1660 * NOTE: Reloc and log trees can't be read by this function as they share the
1661 *	 same root objectid.
1662 *
1663 * @objectid:	root id
1664 * @anon_dev:	preallocated anonymous block device number for new roots,
1665 * 		pass 0 for new allocation.
1666 * @check_ref:	whether to check root item references, If true, return -ENOENT
1667 *		for orphan roots
1668 */
1669static struct btrfs_root *btrfs_get_root_ref(struct btrfs_fs_info *fs_info,
1670					     u64 objectid, dev_t anon_dev,
1671					     bool check_ref)
1672{
1673	struct btrfs_root *root;
1674	struct btrfs_path *path;
1675	struct btrfs_key key;
1676	int ret;
1677
1678	root = btrfs_get_global_root(fs_info, objectid);
1679	if (root)
1680		return root;
 
 
 
 
 
 
 
 
 
 
1681again:
1682	root = btrfs_lookup_fs_root(fs_info, objectid);
1683	if (root) {
1684		/* Shouldn't get preallocated anon_dev for cached roots */
1685		ASSERT(!anon_dev);
 
 
 
 
 
 
 
 
 
1686		if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1687			btrfs_put_root(root);
1688			return ERR_PTR(-ENOENT);
1689		}
1690		return root;
1691	}
1692
1693	key.objectid = objectid;
1694	key.type = BTRFS_ROOT_ITEM_KEY;
1695	key.offset = (u64)-1;
1696	root = btrfs_read_tree_root(fs_info->tree_root, &key);
1697	if (IS_ERR(root))
1698		return root;
1699
1700	if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1701		ret = -ENOENT;
1702		goto fail;
1703	}
1704
1705	ret = btrfs_init_fs_root(root, anon_dev);
1706	if (ret)
1707		goto fail;
1708
1709	path = btrfs_alloc_path();
1710	if (!path) {
1711		ret = -ENOMEM;
1712		goto fail;
1713	}
1714	key.objectid = BTRFS_ORPHAN_OBJECTID;
1715	key.type = BTRFS_ORPHAN_ITEM_KEY;
1716	key.offset = objectid;
1717
1718	ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
1719	btrfs_free_path(path);
1720	if (ret < 0)
1721		goto fail;
1722	if (ret == 0)
1723		set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state);
1724
1725	ret = btrfs_insert_fs_root(fs_info, root);
1726	if (ret) {
1727		btrfs_put_root(root);
1728		if (ret == -EEXIST)
1729			goto again;
 
1730		goto fail;
1731	}
1732	return root;
1733fail:
 
 
 
 
 
 
 
 
1734	btrfs_put_root(root);
1735	return ERR_PTR(ret);
1736}
1737
1738/*
1739 * Get in-memory reference of a root structure
1740 *
1741 * @objectid:	tree objectid
1742 * @check_ref:	if set, verify that the tree exists and the item has at least
1743 *		one reference
1744 */
1745struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
1746				     u64 objectid, bool check_ref)
1747{
1748	return btrfs_get_root_ref(fs_info, objectid, 0, check_ref);
1749}
1750
1751/*
1752 * Get in-memory reference of a root structure, created as new, optionally pass
1753 * the anonymous block device id
1754 *
1755 * @objectid:	tree objectid
1756 * @anon_dev:	if zero, allocate a new anonymous block device or use the
1757 *		parameter value
1758 */
1759struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
1760					 u64 objectid, dev_t anon_dev)
1761{
1762	return btrfs_get_root_ref(fs_info, objectid, anon_dev, true);
1763}
1764
1765/*
1766 * btrfs_get_fs_root_commit_root - return a root for the given objectid
 
1767 * @fs_info:	the fs_info
1768 * @objectid:	the objectid we need to lookup
1769 *
1770 * This is exclusively used for backref walking, and exists specifically because
1771 * of how qgroups does lookups.  Qgroups will do a backref lookup at delayed ref
1772 * creation time, which means we may have to read the tree_root in order to look
1773 * up a fs root that is not in memory.  If the root is not in memory we will
1774 * read the tree root commit root and look up the fs root from there.  This is a
1775 * temporary root, it will not be inserted into the radix tree as it doesn't
1776 * have the most uptodate information, it'll simply be discarded once the
1777 * backref code is finished using the root.
1778 */
1779struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
1780						 struct btrfs_path *path,
1781						 u64 objectid)
1782{
1783	struct btrfs_root *root;
1784	struct btrfs_key key;
1785
1786	ASSERT(path->search_commit_root && path->skip_locking);
1787
1788	/*
1789	 * This can return -ENOENT if we ask for a root that doesn't exist, but
1790	 * since this is called via the backref walking code we won't be looking
1791	 * up a root that doesn't exist, unless there's corruption.  So if root
1792	 * != NULL just return it.
1793	 */
1794	root = btrfs_get_global_root(fs_info, objectid);
1795	if (root)
1796		return root;
1797
1798	root = btrfs_lookup_fs_root(fs_info, objectid);
1799	if (root)
1800		return root;
1801
1802	key.objectid = objectid;
1803	key.type = BTRFS_ROOT_ITEM_KEY;
1804	key.offset = (u64)-1;
1805	root = read_tree_root_path(fs_info->tree_root, path, &key);
1806	btrfs_release_path(path);
1807
1808	return root;
1809}
1810
1811/*
1812 * called by the kthread helper functions to finally call the bio end_io
1813 * functions.  This is where read checksum verification actually happens
1814 */
1815static void end_workqueue_fn(struct btrfs_work *work)
1816{
1817	struct bio *bio;
1818	struct btrfs_end_io_wq *end_io_wq;
1819
1820	end_io_wq = container_of(work, struct btrfs_end_io_wq, work);
1821	bio = end_io_wq->bio;
1822
1823	bio->bi_status = end_io_wq->status;
1824	bio->bi_private = end_io_wq->private;
1825	bio->bi_end_io = end_io_wq->end_io;
1826	bio_endio(bio);
1827	kmem_cache_free(btrfs_end_io_wq_cache, end_io_wq);
1828}
1829
1830static int cleaner_kthread(void *arg)
1831{
1832	struct btrfs_root *root = arg;
1833	struct btrfs_fs_info *fs_info = root->fs_info;
1834	int again;
1835
1836	while (1) {
1837		again = 0;
1838
1839		set_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1840
1841		/* Make the cleaner go to sleep early. */
1842		if (btrfs_need_cleaner_sleep(fs_info))
1843			goto sleep;
1844
1845		/*
1846		 * Do not do anything if we might cause open_ctree() to block
1847		 * before we have finished mounting the filesystem.
1848		 */
1849		if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags))
1850			goto sleep;
1851
1852		if (!mutex_trylock(&fs_info->cleaner_mutex))
1853			goto sleep;
1854
1855		/*
1856		 * Avoid the problem that we change the status of the fs
1857		 * during the above check and trylock.
1858		 */
1859		if (btrfs_need_cleaner_sleep(fs_info)) {
1860			mutex_unlock(&fs_info->cleaner_mutex);
1861			goto sleep;
1862		}
1863
 
 
 
1864		btrfs_run_delayed_iputs(fs_info);
1865
1866		again = btrfs_clean_one_deleted_snapshot(root);
1867		mutex_unlock(&fs_info->cleaner_mutex);
1868
1869		/*
1870		 * The defragger has dealt with the R/O remount and umount,
1871		 * needn't do anything special here.
1872		 */
1873		btrfs_run_defrag_inodes(fs_info);
1874
1875		/*
1876		 * Acquires fs_info->reclaim_bgs_lock to avoid racing
1877		 * with relocation (btrfs_relocate_chunk) and relocation
1878		 * acquires fs_info->cleaner_mutex (btrfs_relocate_block_group)
1879		 * after acquiring fs_info->reclaim_bgs_lock. So we
1880		 * can't hold, nor need to, fs_info->cleaner_mutex when deleting
1881		 * unused block groups.
1882		 */
1883		btrfs_delete_unused_bgs(fs_info);
1884
1885		/*
1886		 * Reclaim block groups in the reclaim_bgs list after we deleted
1887		 * all unused block_groups. This possibly gives us some more free
1888		 * space.
1889		 */
1890		btrfs_reclaim_bgs(fs_info);
1891sleep:
1892		clear_and_wake_up_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1893		if (kthread_should_park())
1894			kthread_parkme();
1895		if (kthread_should_stop())
1896			return 0;
1897		if (!again) {
1898			set_current_state(TASK_INTERRUPTIBLE);
1899			schedule();
1900			__set_current_state(TASK_RUNNING);
1901		}
1902	}
1903}
1904
1905static int transaction_kthread(void *arg)
1906{
1907	struct btrfs_root *root = arg;
1908	struct btrfs_fs_info *fs_info = root->fs_info;
1909	struct btrfs_trans_handle *trans;
1910	struct btrfs_transaction *cur;
1911	u64 transid;
1912	time64_t delta;
1913	unsigned long delay;
1914	bool cannot_commit;
1915
1916	do {
1917		cannot_commit = false;
1918		delay = msecs_to_jiffies(fs_info->commit_interval * 1000);
1919		mutex_lock(&fs_info->transaction_kthread_mutex);
1920
1921		spin_lock(&fs_info->trans_lock);
1922		cur = fs_info->running_transaction;
1923		if (!cur) {
1924			spin_unlock(&fs_info->trans_lock);
1925			goto sleep;
1926		}
1927
1928		delta = ktime_get_seconds() - cur->start_time;
1929		if (cur->state < TRANS_STATE_COMMIT_START &&
 
1930		    delta < fs_info->commit_interval) {
1931			spin_unlock(&fs_info->trans_lock);
1932			delay -= msecs_to_jiffies((delta - 1) * 1000);
1933			delay = min(delay,
1934				    msecs_to_jiffies(fs_info->commit_interval * 1000));
1935			goto sleep;
1936		}
1937		transid = cur->transid;
1938		spin_unlock(&fs_info->trans_lock);
1939
1940		/* If the file system is aborted, this will always fail. */
1941		trans = btrfs_attach_transaction(root);
1942		if (IS_ERR(trans)) {
1943			if (PTR_ERR(trans) != -ENOENT)
1944				cannot_commit = true;
1945			goto sleep;
1946		}
1947		if (transid == trans->transid) {
1948			btrfs_commit_transaction(trans);
1949		} else {
1950			btrfs_end_transaction(trans);
1951		}
1952sleep:
1953		wake_up_process(fs_info->cleaner_kthread);
1954		mutex_unlock(&fs_info->transaction_kthread_mutex);
1955
1956		if (unlikely(test_bit(BTRFS_FS_STATE_ERROR,
1957				      &fs_info->fs_state)))
1958			btrfs_cleanup_transaction(fs_info);
1959		if (!kthread_should_stop() &&
1960				(!btrfs_transaction_blocked(fs_info) ||
1961				 cannot_commit))
1962			schedule_timeout_interruptible(delay);
1963	} while (!kthread_should_stop());
1964	return 0;
1965}
1966
1967/*
1968 * This will find the highest generation in the array of root backups.  The
1969 * index of the highest array is returned, or -EINVAL if we can't find
1970 * anything.
1971 *
1972 * We check to make sure the array is valid by comparing the
1973 * generation of the latest  root in the array with the generation
1974 * in the super block.  If they don't match we pitch it.
1975 */
1976static int find_newest_super_backup(struct btrfs_fs_info *info)
1977{
1978	const u64 newest_gen = btrfs_super_generation(info->super_copy);
1979	u64 cur;
1980	struct btrfs_root_backup *root_backup;
1981	int i;
1982
1983	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
1984		root_backup = info->super_copy->super_roots + i;
1985		cur = btrfs_backup_tree_root_gen(root_backup);
1986		if (cur == newest_gen)
1987			return i;
1988	}
1989
1990	return -EINVAL;
1991}
1992
1993/*
1994 * copy all the root pointers into the super backup array.
1995 * this will bump the backup pointer by one when it is
1996 * done
1997 */
1998static void backup_super_roots(struct btrfs_fs_info *info)
1999{
2000	const int next_backup = info->backup_root_index;
2001	struct btrfs_root_backup *root_backup;
2002
2003	root_backup = info->super_for_commit->super_roots + next_backup;
2004
2005	/*
2006	 * make sure all of our padding and empty slots get zero filled
2007	 * regardless of which ones we use today
2008	 */
2009	memset(root_backup, 0, sizeof(*root_backup));
2010
2011	info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
2012
2013	btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
2014	btrfs_set_backup_tree_root_gen(root_backup,
2015			       btrfs_header_generation(info->tree_root->node));
2016
2017	btrfs_set_backup_tree_root_level(root_backup,
2018			       btrfs_header_level(info->tree_root->node));
2019
2020	btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
2021	btrfs_set_backup_chunk_root_gen(root_backup,
2022			       btrfs_header_generation(info->chunk_root->node));
2023	btrfs_set_backup_chunk_root_level(root_backup,
2024			       btrfs_header_level(info->chunk_root->node));
2025
2026	btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start);
2027	btrfs_set_backup_extent_root_gen(root_backup,
2028			       btrfs_header_generation(info->extent_root->node));
2029	btrfs_set_backup_extent_root_level(root_backup,
2030			       btrfs_header_level(info->extent_root->node));
 
 
 
 
 
 
 
 
 
 
 
 
2031
2032	/*
2033	 * we might commit during log recovery, which happens before we set
2034	 * the fs_root.  Make sure it is valid before we fill it in.
2035	 */
2036	if (info->fs_root && info->fs_root->node) {
2037		btrfs_set_backup_fs_root(root_backup,
2038					 info->fs_root->node->start);
2039		btrfs_set_backup_fs_root_gen(root_backup,
2040			       btrfs_header_generation(info->fs_root->node));
2041		btrfs_set_backup_fs_root_level(root_backup,
2042			       btrfs_header_level(info->fs_root->node));
2043	}
2044
2045	btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
2046	btrfs_set_backup_dev_root_gen(root_backup,
2047			       btrfs_header_generation(info->dev_root->node));
2048	btrfs_set_backup_dev_root_level(root_backup,
2049				       btrfs_header_level(info->dev_root->node));
2050
2051	btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start);
2052	btrfs_set_backup_csum_root_gen(root_backup,
2053			       btrfs_header_generation(info->csum_root->node));
2054	btrfs_set_backup_csum_root_level(root_backup,
2055			       btrfs_header_level(info->csum_root->node));
2056
2057	btrfs_set_backup_total_bytes(root_backup,
2058			     btrfs_super_total_bytes(info->super_copy));
2059	btrfs_set_backup_bytes_used(root_backup,
2060			     btrfs_super_bytes_used(info->super_copy));
2061	btrfs_set_backup_num_devices(root_backup,
2062			     btrfs_super_num_devices(info->super_copy));
2063
2064	/*
2065	 * if we don't copy this out to the super_copy, it won't get remembered
2066	 * for the next commit
2067	 */
2068	memcpy(&info->super_copy->super_roots,
2069	       &info->super_for_commit->super_roots,
2070	       sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
2071}
2072
2073/*
2074 * read_backup_root - Reads a backup root based on the passed priority. Prio 0
2075 * is the newest, prio 1/2/3 are 2nd newest/3rd newest/4th (oldest) backup roots
2076 *
2077 * fs_info - filesystem whose backup roots need to be read
2078 * priority - priority of backup root required
2079 *
2080 * Returns backup root index on success and -EINVAL otherwise.
2081 */
2082static int read_backup_root(struct btrfs_fs_info *fs_info, u8 priority)
2083{
2084	int backup_index = find_newest_super_backup(fs_info);
2085	struct btrfs_super_block *super = fs_info->super_copy;
2086	struct btrfs_root_backup *root_backup;
2087
2088	if (priority < BTRFS_NUM_BACKUP_ROOTS && backup_index >= 0) {
2089		if (priority == 0)
2090			return backup_index;
2091
2092		backup_index = backup_index + BTRFS_NUM_BACKUP_ROOTS - priority;
2093		backup_index %= BTRFS_NUM_BACKUP_ROOTS;
2094	} else {
2095		return -EINVAL;
2096	}
2097
2098	root_backup = super->super_roots + backup_index;
2099
2100	btrfs_set_super_generation(super,
2101				   btrfs_backup_tree_root_gen(root_backup));
2102	btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
2103	btrfs_set_super_root_level(super,
2104				   btrfs_backup_tree_root_level(root_backup));
2105	btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
2106
2107	/*
2108	 * Fixme: the total bytes and num_devices need to match or we should
2109	 * need a fsck
2110	 */
2111	btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
2112	btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
2113
2114	return backup_index;
2115}
2116
2117/* helper to cleanup workers */
2118static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
2119{
2120	btrfs_destroy_workqueue(fs_info->fixup_workers);
2121	btrfs_destroy_workqueue(fs_info->delalloc_workers);
2122	btrfs_destroy_workqueue(fs_info->workers);
2123	btrfs_destroy_workqueue(fs_info->endio_workers);
2124	btrfs_destroy_workqueue(fs_info->endio_raid56_workers);
2125	btrfs_destroy_workqueue(fs_info->rmw_workers);
 
 
 
2126	btrfs_destroy_workqueue(fs_info->endio_write_workers);
2127	btrfs_destroy_workqueue(fs_info->endio_freespace_worker);
2128	btrfs_destroy_workqueue(fs_info->delayed_workers);
2129	btrfs_destroy_workqueue(fs_info->caching_workers);
2130	btrfs_destroy_workqueue(fs_info->readahead_workers);
2131	btrfs_destroy_workqueue(fs_info->flush_workers);
2132	btrfs_destroy_workqueue(fs_info->qgroup_rescan_workers);
2133	if (fs_info->discard_ctl.discard_workers)
2134		destroy_workqueue(fs_info->discard_ctl.discard_workers);
2135	/*
2136	 * Now that all other work queues are destroyed, we can safely destroy
2137	 * the queues used for metadata I/O, since tasks from those other work
2138	 * queues can do metadata I/O operations.
2139	 */
2140	btrfs_destroy_workqueue(fs_info->endio_meta_workers);
2141	btrfs_destroy_workqueue(fs_info->endio_meta_write_workers);
2142}
2143
2144static void free_root_extent_buffers(struct btrfs_root *root)
2145{
2146	if (root) {
2147		free_extent_buffer(root->node);
2148		free_extent_buffer(root->commit_root);
2149		root->node = NULL;
2150		root->commit_root = NULL;
2151	}
2152}
2153
 
 
 
 
 
 
 
 
 
 
2154/* helper to cleanup tree roots */
2155static void free_root_pointers(struct btrfs_fs_info *info, bool free_chunk_root)
2156{
2157	free_root_extent_buffers(info->tree_root);
2158
 
2159	free_root_extent_buffers(info->dev_root);
2160	free_root_extent_buffers(info->extent_root);
2161	free_root_extent_buffers(info->csum_root);
2162	free_root_extent_buffers(info->quota_root);
2163	free_root_extent_buffers(info->uuid_root);
2164	free_root_extent_buffers(info->fs_root);
2165	free_root_extent_buffers(info->data_reloc_root);
 
 
2166	if (free_chunk_root)
2167		free_root_extent_buffers(info->chunk_root);
2168	free_root_extent_buffers(info->free_space_root);
2169}
2170
2171void btrfs_put_root(struct btrfs_root *root)
2172{
2173	if (!root)
2174		return;
2175
2176	if (refcount_dec_and_test(&root->refs)) {
2177		WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
2178		WARN_ON(test_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state));
2179		if (root->anon_dev)
2180			free_anon_bdev(root->anon_dev);
2181		btrfs_drew_lock_destroy(&root->snapshot_lock);
2182		free_root_extent_buffers(root);
2183#ifdef CONFIG_BTRFS_DEBUG
2184		spin_lock(&root->fs_info->fs_roots_radix_lock);
2185		list_del_init(&root->leak_list);
2186		spin_unlock(&root->fs_info->fs_roots_radix_lock);
2187#endif
2188		kfree(root);
2189	}
2190}
2191
2192void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info)
2193{
2194	int ret;
2195	struct btrfs_root *gang[8];
2196	int i;
2197
2198	while (!list_empty(&fs_info->dead_roots)) {
2199		gang[0] = list_entry(fs_info->dead_roots.next,
2200				     struct btrfs_root, root_list);
2201		list_del(&gang[0]->root_list);
2202
2203		if (test_bit(BTRFS_ROOT_IN_RADIX, &gang[0]->state))
2204			btrfs_drop_and_free_fs_root(fs_info, gang[0]);
2205		btrfs_put_root(gang[0]);
2206	}
2207
2208	while (1) {
2209		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2210					     (void **)gang, 0,
2211					     ARRAY_SIZE(gang));
2212		if (!ret)
2213			break;
2214		for (i = 0; i < ret; i++)
2215			btrfs_drop_and_free_fs_root(fs_info, gang[i]);
2216	}
2217}
2218
2219static void btrfs_init_scrub(struct btrfs_fs_info *fs_info)
2220{
2221	mutex_init(&fs_info->scrub_lock);
2222	atomic_set(&fs_info->scrubs_running, 0);
2223	atomic_set(&fs_info->scrub_pause_req, 0);
2224	atomic_set(&fs_info->scrubs_paused, 0);
2225	atomic_set(&fs_info->scrub_cancel_req, 0);
2226	init_waitqueue_head(&fs_info->scrub_pause_wait);
2227	refcount_set(&fs_info->scrub_workers_refcnt, 0);
2228}
2229
2230static void btrfs_init_balance(struct btrfs_fs_info *fs_info)
2231{
2232	spin_lock_init(&fs_info->balance_lock);
2233	mutex_init(&fs_info->balance_mutex);
2234	atomic_set(&fs_info->balance_pause_req, 0);
2235	atomic_set(&fs_info->balance_cancel_req, 0);
2236	fs_info->balance_ctl = NULL;
2237	init_waitqueue_head(&fs_info->balance_wait_q);
2238	atomic_set(&fs_info->reloc_cancel_req, 0);
2239}
2240
2241static void btrfs_init_btree_inode(struct btrfs_fs_info *fs_info)
2242{
2243	struct inode *inode = fs_info->btree_inode;
 
 
 
 
 
 
 
2244
2245	inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
2246	set_nlink(inode, 1);
2247	/*
2248	 * we set the i_size on the btree inode to the max possible int.
2249	 * the real end of the address space is determined by all of
2250	 * the devices in the system
2251	 */
2252	inode->i_size = OFFSET_MAX;
2253	inode->i_mapping->a_ops = &btree_aops;
 
2254
2255	RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
2256	extent_io_tree_init(fs_info, &BTRFS_I(inode)->io_tree,
2257			    IO_TREE_BTREE_INODE_IO, inode);
2258	BTRFS_I(inode)->io_tree.track_uptodate = false;
2259	extent_map_tree_init(&BTRFS_I(inode)->extent_tree);
2260
2261	BTRFS_I(inode)->root = btrfs_grab_root(fs_info->tree_root);
2262	memset(&BTRFS_I(inode)->location, 0, sizeof(struct btrfs_key));
 
 
2263	set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
2264	btrfs_insert_inode_hash(inode);
 
 
 
2265}
2266
2267static void btrfs_init_dev_replace_locks(struct btrfs_fs_info *fs_info)
2268{
2269	mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount);
2270	init_rwsem(&fs_info->dev_replace.rwsem);
2271	init_waitqueue_head(&fs_info->dev_replace.replace_wait);
2272}
2273
2274static void btrfs_init_qgroup(struct btrfs_fs_info *fs_info)
2275{
2276	spin_lock_init(&fs_info->qgroup_lock);
2277	mutex_init(&fs_info->qgroup_ioctl_lock);
2278	fs_info->qgroup_tree = RB_ROOT;
2279	INIT_LIST_HEAD(&fs_info->dirty_qgroups);
2280	fs_info->qgroup_seq = 1;
2281	fs_info->qgroup_ulist = NULL;
2282	fs_info->qgroup_rescan_running = false;
 
2283	mutex_init(&fs_info->qgroup_rescan_lock);
2284}
2285
2286static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info,
2287		struct btrfs_fs_devices *fs_devices)
2288{
2289	u32 max_active = fs_info->thread_pool_size;
2290	unsigned int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND;
 
2291
2292	fs_info->workers =
2293		btrfs_alloc_workqueue(fs_info, "worker",
2294				      flags | WQ_HIGHPRI, max_active, 16);
2295
2296	fs_info->delalloc_workers =
2297		btrfs_alloc_workqueue(fs_info, "delalloc",
2298				      flags, max_active, 2);
2299
2300	fs_info->flush_workers =
2301		btrfs_alloc_workqueue(fs_info, "flush_delalloc",
2302				      flags, max_active, 0);
2303
2304	fs_info->caching_workers =
2305		btrfs_alloc_workqueue(fs_info, "cache", flags, max_active, 0);
2306
2307	fs_info->fixup_workers =
2308		btrfs_alloc_workqueue(fs_info, "fixup", flags, 1, 0);
2309
2310	/*
2311	 * endios are largely parallel and should have a very
2312	 * low idle thresh
2313	 */
2314	fs_info->endio_workers =
2315		btrfs_alloc_workqueue(fs_info, "endio", flags, max_active, 4);
2316	fs_info->endio_meta_workers =
2317		btrfs_alloc_workqueue(fs_info, "endio-meta", flags,
2318				      max_active, 4);
2319	fs_info->endio_meta_write_workers =
2320		btrfs_alloc_workqueue(fs_info, "endio-meta-write", flags,
2321				      max_active, 2);
2322	fs_info->endio_raid56_workers =
2323		btrfs_alloc_workqueue(fs_info, "endio-raid56", flags,
2324				      max_active, 4);
2325	fs_info->rmw_workers =
2326		btrfs_alloc_workqueue(fs_info, "rmw", flags, max_active, 2);
2327	fs_info->endio_write_workers =
2328		btrfs_alloc_workqueue(fs_info, "endio-write", flags,
2329				      max_active, 2);
 
 
2330	fs_info->endio_freespace_worker =
2331		btrfs_alloc_workqueue(fs_info, "freespace-write", flags,
2332				      max_active, 0);
2333	fs_info->delayed_workers =
2334		btrfs_alloc_workqueue(fs_info, "delayed-meta", flags,
2335				      max_active, 0);
2336	fs_info->readahead_workers =
2337		btrfs_alloc_workqueue(fs_info, "readahead", flags,
2338				      max_active, 2);
2339	fs_info->qgroup_rescan_workers =
2340		btrfs_alloc_workqueue(fs_info, "qgroup-rescan", flags, 1, 0);
 
2341	fs_info->discard_ctl.discard_workers =
2342		alloc_workqueue("btrfs_discard", WQ_UNBOUND | WQ_FREEZABLE, 1);
2343
2344	if (!(fs_info->workers && fs_info->delalloc_workers &&
2345	      fs_info->flush_workers &&
2346	      fs_info->endio_workers && fs_info->endio_meta_workers &&
2347	      fs_info->endio_meta_write_workers &&
2348	      fs_info->endio_write_workers && fs_info->endio_raid56_workers &&
2349	      fs_info->endio_freespace_worker && fs_info->rmw_workers &&
2350	      fs_info->caching_workers && fs_info->readahead_workers &&
2351	      fs_info->fixup_workers && fs_info->delayed_workers &&
2352	      fs_info->qgroup_rescan_workers &&
2353	      fs_info->discard_ctl.discard_workers)) {
2354		return -ENOMEM;
2355	}
2356
2357	return 0;
2358}
2359
2360static int btrfs_init_csum_hash(struct btrfs_fs_info *fs_info, u16 csum_type)
2361{
2362	struct crypto_shash *csum_shash;
2363	const char *csum_driver = btrfs_super_csum_driver(csum_type);
2364
2365	csum_shash = crypto_alloc_shash(csum_driver, 0, 0);
2366
2367	if (IS_ERR(csum_shash)) {
2368		btrfs_err(fs_info, "error allocating %s hash for checksum",
2369			  csum_driver);
2370		return PTR_ERR(csum_shash);
2371	}
2372
2373	fs_info->csum_shash = csum_shash;
2374
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2375	return 0;
2376}
2377
2378static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
2379			    struct btrfs_fs_devices *fs_devices)
2380{
2381	int ret;
 
2382	struct btrfs_root *log_tree_root;
2383	struct btrfs_super_block *disk_super = fs_info->super_copy;
2384	u64 bytenr = btrfs_super_log_root(disk_super);
2385	int level = btrfs_super_log_root_level(disk_super);
2386
2387	if (fs_devices->rw_devices == 0) {
2388		btrfs_warn(fs_info, "log replay required on RO media");
2389		return -EIO;
2390	}
2391
2392	log_tree_root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID,
2393					 GFP_KERNEL);
2394	if (!log_tree_root)
2395		return -ENOMEM;
2396
2397	log_tree_root->node = read_tree_block(fs_info, bytenr,
2398					      BTRFS_TREE_LOG_OBJECTID,
2399					      fs_info->generation + 1, level,
2400					      NULL);
2401	if (IS_ERR(log_tree_root->node)) {
2402		btrfs_warn(fs_info, "failed to read log tree");
2403		ret = PTR_ERR(log_tree_root->node);
2404		log_tree_root->node = NULL;
2405		btrfs_put_root(log_tree_root);
2406		return ret;
2407	} else if (!extent_buffer_uptodate(log_tree_root->node)) {
 
2408		btrfs_err(fs_info, "failed to read log tree");
2409		btrfs_put_root(log_tree_root);
2410		return -EIO;
2411	}
 
2412	/* returns with log_tree_root freed on success */
2413	ret = btrfs_recover_log_trees(log_tree_root);
2414	if (ret) {
2415		btrfs_handle_fs_error(fs_info, ret,
2416				      "Failed to recover log tree");
2417		btrfs_put_root(log_tree_root);
2418		return ret;
2419	}
2420
2421	if (sb_rdonly(fs_info->sb)) {
2422		ret = btrfs_commit_super(fs_info);
2423		if (ret)
2424			return ret;
2425	}
2426
2427	return 0;
2428}
2429
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2430static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
2431{
2432	struct btrfs_root *tree_root = fs_info->tree_root;
2433	struct btrfs_root *root;
2434	struct btrfs_key location;
2435	int ret;
2436
2437	BUG_ON(!fs_info->tree_root);
2438
2439	location.objectid = BTRFS_EXTENT_TREE_OBJECTID;
 
 
 
2440	location.type = BTRFS_ROOT_ITEM_KEY;
2441	location.offset = 0;
2442
2443	root = btrfs_read_tree_root(tree_root, &location);
2444	if (IS_ERR(root)) {
2445		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2446			ret = PTR_ERR(root);
2447			goto out;
 
 
 
 
 
 
2448		}
2449	} else {
2450		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2451		fs_info->extent_root = root;
2452	}
2453
2454	location.objectid = BTRFS_DEV_TREE_OBJECTID;
2455	root = btrfs_read_tree_root(tree_root, &location);
2456	if (IS_ERR(root)) {
2457		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2458			ret = PTR_ERR(root);
2459			goto out;
2460		}
2461	} else {
2462		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2463		fs_info->dev_root = root;
2464	}
2465	/* Initialize fs_info for all devices in any case */
2466	btrfs_init_devices_late(fs_info);
2467
2468	/* If IGNOREDATACSUMS is set don't bother reading the csum root. */
2469	if (!btrfs_test_opt(fs_info, IGNOREDATACSUMS)) {
2470		location.objectid = BTRFS_CSUM_TREE_OBJECTID;
2471		root = btrfs_read_tree_root(tree_root, &location);
2472		if (IS_ERR(root)) {
2473			if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2474				ret = PTR_ERR(root);
2475				goto out;
2476			}
2477		} else {
2478			set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2479			fs_info->csum_root = root;
2480		}
2481	}
2482
2483	/*
2484	 * This tree can share blocks with some other fs tree during relocation
2485	 * and we need a proper setup by btrfs_get_fs_root
2486	 */
2487	root = btrfs_get_fs_root(tree_root->fs_info,
2488				 BTRFS_DATA_RELOC_TREE_OBJECTID, true);
2489	if (IS_ERR(root)) {
2490		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2491			ret = PTR_ERR(root);
2492			goto out;
2493		}
2494	} else {
2495		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2496		fs_info->data_reloc_root = root;
2497	}
2498
2499	location.objectid = BTRFS_QUOTA_TREE_OBJECTID;
2500	root = btrfs_read_tree_root(tree_root, &location);
2501	if (!IS_ERR(root)) {
2502		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2503		set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
2504		fs_info->quota_root = root;
2505	}
2506
2507	location.objectid = BTRFS_UUID_TREE_OBJECTID;
2508	root = btrfs_read_tree_root(tree_root, &location);
2509	if (IS_ERR(root)) {
2510		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2511			ret = PTR_ERR(root);
2512			if (ret != -ENOENT)
2513				goto out;
2514		}
2515	} else {
2516		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2517		fs_info->uuid_root = root;
2518	}
2519
2520	if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
2521		location.objectid = BTRFS_FREE_SPACE_TREE_OBJECTID;
2522		root = btrfs_read_tree_root(tree_root, &location);
2523		if (IS_ERR(root)) {
2524			if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2525				ret = PTR_ERR(root);
2526				goto out;
2527			}
2528		}  else {
2529			set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2530			fs_info->free_space_root = root;
2531		}
2532	}
2533
2534	return 0;
2535out:
2536	btrfs_warn(fs_info, "failed to read root (objectid=%llu): %d",
2537		   location.objectid, ret);
2538	return ret;
2539}
2540
2541/*
2542 * Real super block validation
2543 * NOTE: super csum type and incompat features will not be checked here.
2544 *
2545 * @sb:		super block to check
2546 * @mirror_num:	the super block number to check its bytenr:
2547 * 		0	the primary (1st) sb
2548 * 		1, 2	2nd and 3rd backup copy
2549 * 	       -1	skip bytenr check
2550 */
2551static int validate_super(struct btrfs_fs_info *fs_info,
2552			    struct btrfs_super_block *sb, int mirror_num)
2553{
2554	u64 nodesize = btrfs_super_nodesize(sb);
2555	u64 sectorsize = btrfs_super_sectorsize(sb);
2556	int ret = 0;
2557
2558	if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
2559		btrfs_err(fs_info, "no valid FS found");
2560		ret = -EINVAL;
2561	}
2562	if (btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP) {
2563		btrfs_err(fs_info, "unrecognized or unsupported super flag: %llu",
2564				btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);
2565		ret = -EINVAL;
2566	}
2567	if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
2568		btrfs_err(fs_info, "tree_root level too big: %d >= %d",
2569				btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
2570		ret = -EINVAL;
2571	}
2572	if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
2573		btrfs_err(fs_info, "chunk_root level too big: %d >= %d",
2574				btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
2575		ret = -EINVAL;
2576	}
2577	if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
2578		btrfs_err(fs_info, "log_root level too big: %d >= %d",
2579				btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
2580		ret = -EINVAL;
2581	}
2582
2583	/*
2584	 * Check sectorsize and nodesize first, other check will need it.
2585	 * Check all possible sectorsize(4K, 8K, 16K, 32K, 64K) here.
2586	 */
2587	if (!is_power_of_2(sectorsize) || sectorsize < 4096 ||
2588	    sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2589		btrfs_err(fs_info, "invalid sectorsize %llu", sectorsize);
2590		ret = -EINVAL;
2591	}
2592
2593	/*
2594	 * For 4K page size, we only support 4K sector size.
2595	 * For 64K page size, we support read-write for 64K sector size, and
2596	 * read-only for 4K sector size.
2597	 */
2598	if ((PAGE_SIZE == SZ_4K && sectorsize != PAGE_SIZE) ||
2599	    (PAGE_SIZE == SZ_64K && (sectorsize != SZ_4K &&
2600				     sectorsize != SZ_64K))) {
 
2601		btrfs_err(fs_info,
2602			"sectorsize %llu not yet supported for page size %lu",
2603			sectorsize, PAGE_SIZE);
2604		ret = -EINVAL;
2605	}
2606
2607	if (!is_power_of_2(nodesize) || nodesize < sectorsize ||
2608	    nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2609		btrfs_err(fs_info, "invalid nodesize %llu", nodesize);
2610		ret = -EINVAL;
2611	}
2612	if (nodesize != le32_to_cpu(sb->__unused_leafsize)) {
2613		btrfs_err(fs_info, "invalid leafsize %u, should be %llu",
2614			  le32_to_cpu(sb->__unused_leafsize), nodesize);
2615		ret = -EINVAL;
2616	}
2617
2618	/* Root alignment check */
2619	if (!IS_ALIGNED(btrfs_super_root(sb), sectorsize)) {
2620		btrfs_warn(fs_info, "tree_root block unaligned: %llu",
2621			   btrfs_super_root(sb));
2622		ret = -EINVAL;
2623	}
2624	if (!IS_ALIGNED(btrfs_super_chunk_root(sb), sectorsize)) {
2625		btrfs_warn(fs_info, "chunk_root block unaligned: %llu",
2626			   btrfs_super_chunk_root(sb));
2627		ret = -EINVAL;
2628	}
2629	if (!IS_ALIGNED(btrfs_super_log_root(sb), sectorsize)) {
2630		btrfs_warn(fs_info, "log_root block unaligned: %llu",
2631			   btrfs_super_log_root(sb));
2632		ret = -EINVAL;
2633	}
2634
2635	if (memcmp(fs_info->fs_devices->fsid, fs_info->super_copy->fsid,
2636		   BTRFS_FSID_SIZE)) {
2637		btrfs_err(fs_info,
2638		"superblock fsid doesn't match fsid of fs_devices: %pU != %pU",
2639			fs_info->super_copy->fsid, fs_info->fs_devices->fsid);
2640		ret = -EINVAL;
2641	}
2642
2643	if (btrfs_fs_incompat(fs_info, METADATA_UUID) &&
2644	    memcmp(fs_info->fs_devices->metadata_uuid,
2645		   fs_info->super_copy->metadata_uuid, BTRFS_FSID_SIZE)) {
2646		btrfs_err(fs_info,
2647"superblock metadata_uuid doesn't match metadata uuid of fs_devices: %pU != %pU",
2648			fs_info->super_copy->metadata_uuid,
2649			fs_info->fs_devices->metadata_uuid);
2650		ret = -EINVAL;
2651	}
2652
2653	if (memcmp(fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid,
2654		   BTRFS_FSID_SIZE) != 0) {
2655		btrfs_err(fs_info,
2656			"dev_item UUID does not match metadata fsid: %pU != %pU",
2657			fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid);
2658		ret = -EINVAL;
2659	}
2660
2661	/*
 
 
 
 
 
 
 
 
 
 
 
 
2662	 * Hint to catch really bogus numbers, bitflips or so, more exact checks are
2663	 * done later
2664	 */
2665	if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) {
2666		btrfs_err(fs_info, "bytes_used is too small %llu",
2667			  btrfs_super_bytes_used(sb));
2668		ret = -EINVAL;
2669	}
2670	if (!is_power_of_2(btrfs_super_stripesize(sb))) {
2671		btrfs_err(fs_info, "invalid stripesize %u",
2672			  btrfs_super_stripesize(sb));
2673		ret = -EINVAL;
2674	}
2675	if (btrfs_super_num_devices(sb) > (1UL << 31))
2676		btrfs_warn(fs_info, "suspicious number of devices: %llu",
2677			   btrfs_super_num_devices(sb));
2678	if (btrfs_super_num_devices(sb) == 0) {
2679		btrfs_err(fs_info, "number of devices is 0");
2680		ret = -EINVAL;
2681	}
2682
2683	if (mirror_num >= 0 &&
2684	    btrfs_super_bytenr(sb) != btrfs_sb_offset(mirror_num)) {
2685		btrfs_err(fs_info, "super offset mismatch %llu != %u",
2686			  btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET);
2687		ret = -EINVAL;
2688	}
2689
2690	/*
2691	 * Obvious sys_chunk_array corruptions, it must hold at least one key
2692	 * and one chunk
2693	 */
2694	if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
2695		btrfs_err(fs_info, "system chunk array too big %u > %u",
2696			  btrfs_super_sys_array_size(sb),
2697			  BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
2698		ret = -EINVAL;
2699	}
2700	if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
2701			+ sizeof(struct btrfs_chunk)) {
2702		btrfs_err(fs_info, "system chunk array too small %u < %zu",
2703			  btrfs_super_sys_array_size(sb),
2704			  sizeof(struct btrfs_disk_key)
2705			  + sizeof(struct btrfs_chunk));
2706		ret = -EINVAL;
2707	}
2708
2709	/*
2710	 * The generation is a global counter, we'll trust it more than the others
2711	 * but it's still possible that it's the one that's wrong.
2712	 */
2713	if (btrfs_super_generation(sb) < btrfs_super_chunk_root_generation(sb))
2714		btrfs_warn(fs_info,
2715			"suspicious: generation < chunk_root_generation: %llu < %llu",
2716			btrfs_super_generation(sb),
2717			btrfs_super_chunk_root_generation(sb));
2718	if (btrfs_super_generation(sb) < btrfs_super_cache_generation(sb)
2719	    && btrfs_super_cache_generation(sb) != (u64)-1)
2720		btrfs_warn(fs_info,
2721			"suspicious: generation < cache_generation: %llu < %llu",
2722			btrfs_super_generation(sb),
2723			btrfs_super_cache_generation(sb));
2724
2725	return ret;
2726}
2727
2728/*
2729 * Validation of super block at mount time.
2730 * Some checks already done early at mount time, like csum type and incompat
2731 * flags will be skipped.
2732 */
2733static int btrfs_validate_mount_super(struct btrfs_fs_info *fs_info)
2734{
2735	return validate_super(fs_info, fs_info->super_copy, 0);
2736}
2737
2738/*
2739 * Validation of super block at write time.
2740 * Some checks like bytenr check will be skipped as their values will be
2741 * overwritten soon.
2742 * Extra checks like csum type and incompat flags will be done here.
2743 */
2744static int btrfs_validate_write_super(struct btrfs_fs_info *fs_info,
2745				      struct btrfs_super_block *sb)
2746{
2747	int ret;
2748
2749	ret = validate_super(fs_info, sb, -1);
2750	if (ret < 0)
2751		goto out;
2752	if (!btrfs_supported_super_csum(btrfs_super_csum_type(sb))) {
2753		ret = -EUCLEAN;
2754		btrfs_err(fs_info, "invalid csum type, has %u want %u",
2755			  btrfs_super_csum_type(sb), BTRFS_CSUM_TYPE_CRC32);
2756		goto out;
2757	}
2758	if (btrfs_super_incompat_flags(sb) & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
2759		ret = -EUCLEAN;
2760		btrfs_err(fs_info,
2761		"invalid incompat flags, has 0x%llx valid mask 0x%llx",
2762			  btrfs_super_incompat_flags(sb),
2763			  (unsigned long long)BTRFS_FEATURE_INCOMPAT_SUPP);
2764		goto out;
2765	}
2766out:
2767	if (ret < 0)
2768		btrfs_err(fs_info,
2769		"super block corruption detected before writing it to disk");
2770	return ret;
2771}
2772
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2773static int __cold init_tree_roots(struct btrfs_fs_info *fs_info)
2774{
2775	int backup_index = find_newest_super_backup(fs_info);
2776	struct btrfs_super_block *sb = fs_info->super_copy;
2777	struct btrfs_root *tree_root = fs_info->tree_root;
2778	bool handle_error = false;
2779	int ret = 0;
2780	int i;
2781
2782	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
2783		u64 generation;
2784		int level;
2785
2786		if (handle_error) {
2787			if (!IS_ERR(tree_root->node))
2788				free_extent_buffer(tree_root->node);
2789			tree_root->node = NULL;
2790
2791			if (!btrfs_test_opt(fs_info, USEBACKUPROOT))
2792				break;
2793
2794			free_root_pointers(fs_info, 0);
2795
2796			/*
2797			 * Don't use the log in recovery mode, it won't be
2798			 * valid
2799			 */
2800			btrfs_set_super_log_root(sb, 0);
2801
2802			/* We can't trust the free space cache either */
2803			btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
2804
2805			ret = read_backup_root(fs_info, i);
2806			backup_index = ret;
2807			if (ret < 0)
2808				return ret;
2809		}
2810		generation = btrfs_super_generation(sb);
2811		level = btrfs_super_root_level(sb);
2812		tree_root->node = read_tree_block(fs_info, btrfs_super_root(sb),
2813						  BTRFS_ROOT_TREE_OBJECTID,
2814						  generation, level, NULL);
2815		if (IS_ERR(tree_root->node)) {
2816			handle_error = true;
2817			ret = PTR_ERR(tree_root->node);
2818			tree_root->node = NULL;
2819			btrfs_warn(fs_info, "couldn't read tree root");
2820			continue;
2821
2822		} else if (!extent_buffer_uptodate(tree_root->node)) {
 
2823			handle_error = true;
2824			ret = -EIO;
2825			btrfs_warn(fs_info, "error while reading tree root");
2826			continue;
2827		}
2828
2829		btrfs_set_root_node(&tree_root->root_item, tree_root->node);
2830		tree_root->commit_root = btrfs_root_node(tree_root);
2831		btrfs_set_root_refs(&tree_root->root_item, 1);
2832
2833		/*
2834		 * No need to hold btrfs_root::objectid_mutex since the fs
2835		 * hasn't been fully initialised and we are the only user
2836		 */
2837		ret = btrfs_init_root_free_objectid(tree_root);
2838		if (ret < 0) {
2839			handle_error = true;
2840			continue;
2841		}
2842
2843		ASSERT(tree_root->free_objectid <= BTRFS_LAST_FREE_OBJECTID);
2844
2845		ret = btrfs_read_roots(fs_info);
2846		if (ret < 0) {
2847			handle_error = true;
2848			continue;
2849		}
2850
2851		/* All successful */
2852		fs_info->generation = generation;
2853		fs_info->last_trans_committed = generation;
 
2854
2855		/* Always begin writing backup roots after the one being used */
2856		if (backup_index < 0) {
2857			fs_info->backup_root_index = 0;
2858		} else {
2859			fs_info->backup_root_index = backup_index + 1;
2860			fs_info->backup_root_index %= BTRFS_NUM_BACKUP_ROOTS;
2861		}
2862		break;
2863	}
2864
2865	return ret;
2866}
2867
2868void btrfs_init_fs_info(struct btrfs_fs_info *fs_info)
2869{
2870	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
2871	INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC);
2872	INIT_LIST_HEAD(&fs_info->trans_list);
2873	INIT_LIST_HEAD(&fs_info->dead_roots);
2874	INIT_LIST_HEAD(&fs_info->delayed_iputs);
2875	INIT_LIST_HEAD(&fs_info->delalloc_roots);
2876	INIT_LIST_HEAD(&fs_info->caching_block_groups);
2877	spin_lock_init(&fs_info->delalloc_root_lock);
2878	spin_lock_init(&fs_info->trans_lock);
2879	spin_lock_init(&fs_info->fs_roots_radix_lock);
2880	spin_lock_init(&fs_info->delayed_iput_lock);
2881	spin_lock_init(&fs_info->defrag_inodes_lock);
2882	spin_lock_init(&fs_info->super_lock);
2883	spin_lock_init(&fs_info->buffer_lock);
2884	spin_lock_init(&fs_info->unused_bgs_lock);
2885	spin_lock_init(&fs_info->treelog_bg_lock);
 
 
2886	rwlock_init(&fs_info->tree_mod_log_lock);
 
2887	mutex_init(&fs_info->unused_bg_unpin_mutex);
2888	mutex_init(&fs_info->reclaim_bgs_lock);
2889	mutex_init(&fs_info->reloc_mutex);
2890	mutex_init(&fs_info->delalloc_root_mutex);
2891	mutex_init(&fs_info->zoned_meta_io_lock);
 
2892	seqlock_init(&fs_info->profiles_lock);
2893
 
 
 
 
 
 
 
 
 
 
 
 
 
2894	INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
2895	INIT_LIST_HEAD(&fs_info->space_info);
2896	INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
2897	INIT_LIST_HEAD(&fs_info->unused_bgs);
2898	INIT_LIST_HEAD(&fs_info->reclaim_bgs);
 
2899#ifdef CONFIG_BTRFS_DEBUG
2900	INIT_LIST_HEAD(&fs_info->allocated_roots);
2901	INIT_LIST_HEAD(&fs_info->allocated_ebs);
2902	spin_lock_init(&fs_info->eb_leak_lock);
2903#endif
2904	extent_map_tree_init(&fs_info->mapping_tree);
 
2905	btrfs_init_block_rsv(&fs_info->global_block_rsv,
2906			     BTRFS_BLOCK_RSV_GLOBAL);
2907	btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
2908	btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK);
2909	btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY);
2910	btrfs_init_block_rsv(&fs_info->delayed_block_rsv,
2911			     BTRFS_BLOCK_RSV_DELOPS);
2912	btrfs_init_block_rsv(&fs_info->delayed_refs_rsv,
2913			     BTRFS_BLOCK_RSV_DELREFS);
2914
2915	atomic_set(&fs_info->async_delalloc_pages, 0);
2916	atomic_set(&fs_info->defrag_running, 0);
2917	atomic_set(&fs_info->reada_works_cnt, 0);
2918	atomic_set(&fs_info->nr_delayed_iputs, 0);
2919	atomic64_set(&fs_info->tree_mod_seq, 0);
 
2920	fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE;
2921	fs_info->metadata_ratio = 0;
2922	fs_info->defrag_inodes = RB_ROOT;
2923	atomic64_set(&fs_info->free_chunk_space, 0);
2924	fs_info->tree_mod_log = RB_ROOT;
2925	fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
2926	fs_info->avg_delayed_ref_runtime = NSEC_PER_SEC >> 6; /* div by 64 */
2927	/* readahead state */
2928	INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
2929	spin_lock_init(&fs_info->reada_lock);
2930	btrfs_init_ref_verify(fs_info);
2931
2932	fs_info->thread_pool_size = min_t(unsigned long,
2933					  num_online_cpus() + 2, 8);
2934
2935	INIT_LIST_HEAD(&fs_info->ordered_roots);
2936	spin_lock_init(&fs_info->ordered_root_lock);
2937
2938	btrfs_init_scrub(fs_info);
2939#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
2940	fs_info->check_integrity_print_mask = 0;
2941#endif
2942	btrfs_init_balance(fs_info);
2943	btrfs_init_async_reclaim_work(fs_info);
2944
2945	spin_lock_init(&fs_info->block_group_cache_lock);
2946	fs_info->block_group_cache_tree = RB_ROOT;
2947	fs_info->first_logical_byte = (u64)-1;
2948
2949	extent_io_tree_init(fs_info, &fs_info->excluded_extents,
2950			    IO_TREE_FS_EXCLUDED_EXTENTS, NULL);
2951	set_bit(BTRFS_FS_BARRIER, &fs_info->flags);
2952
2953	mutex_init(&fs_info->ordered_operations_mutex);
2954	mutex_init(&fs_info->tree_log_mutex);
2955	mutex_init(&fs_info->chunk_mutex);
2956	mutex_init(&fs_info->transaction_kthread_mutex);
2957	mutex_init(&fs_info->cleaner_mutex);
2958	mutex_init(&fs_info->ro_block_group_mutex);
2959	init_rwsem(&fs_info->commit_root_sem);
2960	init_rwsem(&fs_info->cleanup_work_sem);
2961	init_rwsem(&fs_info->subvol_sem);
2962	sema_init(&fs_info->uuid_tree_rescan_sem, 1);
2963
2964	btrfs_init_dev_replace_locks(fs_info);
2965	btrfs_init_qgroup(fs_info);
2966	btrfs_discard_init(fs_info);
2967
2968	btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
2969	btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
2970
2971	init_waitqueue_head(&fs_info->transaction_throttle);
2972	init_waitqueue_head(&fs_info->transaction_wait);
2973	init_waitqueue_head(&fs_info->transaction_blocked_wait);
2974	init_waitqueue_head(&fs_info->async_submit_wait);
2975	init_waitqueue_head(&fs_info->delayed_iputs_wait);
2976
2977	/* Usable values until the real ones are cached from the superblock */
2978	fs_info->nodesize = 4096;
2979	fs_info->sectorsize = 4096;
2980	fs_info->sectorsize_bits = ilog2(4096);
2981	fs_info->stripesize = 4096;
2982
 
 
 
 
 
2983	spin_lock_init(&fs_info->swapfile_pins_lock);
2984	fs_info->swapfile_pins = RB_ROOT;
2985
2986	spin_lock_init(&fs_info->send_reloc_lock);
2987	fs_info->send_in_progress = 0;
2988
2989	fs_info->bg_reclaim_threshold = BTRFS_DEFAULT_RECLAIM_THRESH;
2990	INIT_WORK(&fs_info->reclaim_bgs_work, btrfs_reclaim_bgs_work);
2991}
2992
2993static int init_mount_fs_info(struct btrfs_fs_info *fs_info, struct super_block *sb)
2994{
2995	int ret;
2996
2997	fs_info->sb = sb;
2998	sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE;
2999	sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE);
3000
3001	ret = percpu_counter_init(&fs_info->ordered_bytes, 0, GFP_KERNEL);
3002	if (ret)
3003		return ret;
3004
3005	ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0, GFP_KERNEL);
3006	if (ret)
3007		return ret;
3008
3009	fs_info->dirty_metadata_batch = PAGE_SIZE *
3010					(1 + ilog2(nr_cpu_ids));
3011
3012	ret = percpu_counter_init(&fs_info->delalloc_bytes, 0, GFP_KERNEL);
3013	if (ret)
3014		return ret;
3015
3016	ret = percpu_counter_init(&fs_info->dev_replace.bio_counter, 0,
3017			GFP_KERNEL);
3018	if (ret)
3019		return ret;
3020
3021	fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
3022					GFP_KERNEL);
3023	if (!fs_info->delayed_root)
3024		return -ENOMEM;
3025	btrfs_init_delayed_root(fs_info->delayed_root);
3026
3027	if (sb_rdonly(sb))
3028		set_bit(BTRFS_FS_STATE_RO, &fs_info->fs_state);
3029
3030	return btrfs_alloc_stripe_hash_table(fs_info);
3031}
3032
3033static int btrfs_uuid_rescan_kthread(void *data)
3034{
3035	struct btrfs_fs_info *fs_info = (struct btrfs_fs_info *)data;
3036	int ret;
3037
3038	/*
3039	 * 1st step is to iterate through the existing UUID tree and
3040	 * to delete all entries that contain outdated data.
3041	 * 2nd step is to add all missing entries to the UUID tree.
3042	 */
3043	ret = btrfs_uuid_tree_iterate(fs_info);
3044	if (ret < 0) {
3045		if (ret != -EINTR)
3046			btrfs_warn(fs_info, "iterating uuid_tree failed %d",
3047				   ret);
3048		up(&fs_info->uuid_tree_rescan_sem);
3049		return ret;
3050	}
3051	return btrfs_uuid_scan_kthread(data);
3052}
3053
3054static int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
3055{
3056	struct task_struct *task;
3057
3058	down(&fs_info->uuid_tree_rescan_sem);
3059	task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
3060	if (IS_ERR(task)) {
3061		/* fs_info->update_uuid_tree_gen remains 0 in all error case */
3062		btrfs_warn(fs_info, "failed to start uuid_rescan task");
3063		up(&fs_info->uuid_tree_rescan_sem);
3064		return PTR_ERR(task);
3065	}
3066
3067	return 0;
3068}
3069
3070/*
3071 * Some options only have meaning at mount time and shouldn't persist across
3072 * remounts, or be displayed. Clear these at the end of mount and remount
3073 * code paths.
3074 */
3075void btrfs_clear_oneshot_options(struct btrfs_fs_info *fs_info)
3076{
3077	btrfs_clear_opt(fs_info->mount_opt, USEBACKUPROOT);
3078	btrfs_clear_opt(fs_info->mount_opt, CLEAR_CACHE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3079}
3080
3081/*
3082 * Mounting logic specific to read-write file systems. Shared by open_ctree
3083 * and btrfs_remount when remounting from read-only to read-write.
3084 */
3085int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info)
3086{
3087	int ret;
3088	const bool cache_opt = btrfs_test_opt(fs_info, SPACE_CACHE);
3089	bool clear_free_space_tree = false;
3090
3091	if (btrfs_test_opt(fs_info, CLEAR_CACHE) &&
3092	    btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3093		clear_free_space_tree = true;
 
 
 
 
3094	} else if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
3095		   !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID)) {
3096		btrfs_warn(fs_info, "free space tree is invalid");
3097		clear_free_space_tree = true;
3098	}
3099
3100	if (clear_free_space_tree) {
3101		btrfs_info(fs_info, "clearing free space tree");
3102		ret = btrfs_clear_free_space_tree(fs_info);
3103		if (ret) {
3104			btrfs_warn(fs_info,
3105				   "failed to clear free space tree: %d", ret);
 
 
 
 
 
 
 
 
 
 
 
3106			goto out;
3107		}
3108	}
3109
3110	/*
3111	 * btrfs_find_orphan_roots() is responsible for finding all the dead
3112	 * roots (with 0 refs), flag them with BTRFS_ROOT_DEAD_TREE and load
3113	 * them into the fs_info->fs_roots_radix tree. This must be done before
3114	 * calling btrfs_orphan_cleanup() on the tree root. If we don't do it
3115	 * first, then btrfs_orphan_cleanup() will delete a dead root's orphan
3116	 * item before the root's tree is deleted - this means that if we unmount
3117	 * or crash before the deletion completes, on the next mount we will not
3118	 * delete what remains of the tree because the orphan item does not
3119	 * exists anymore, which is what tells us we have a pending deletion.
3120	 */
3121	ret = btrfs_find_orphan_roots(fs_info);
3122	if (ret)
3123		goto out;
3124
3125	ret = btrfs_cleanup_fs_roots(fs_info);
3126	if (ret)
3127		goto out;
3128
3129	down_read(&fs_info->cleanup_work_sem);
3130	if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) ||
3131	    (ret = btrfs_orphan_cleanup(fs_info->tree_root))) {
3132		up_read(&fs_info->cleanup_work_sem);
3133		goto out;
3134	}
3135	up_read(&fs_info->cleanup_work_sem);
3136
3137	mutex_lock(&fs_info->cleaner_mutex);
3138	ret = btrfs_recover_relocation(fs_info->tree_root);
3139	mutex_unlock(&fs_info->cleaner_mutex);
3140	if (ret < 0) {
3141		btrfs_warn(fs_info, "failed to recover relocation: %d", ret);
3142		goto out;
3143	}
3144
3145	if (btrfs_test_opt(fs_info, FREE_SPACE_TREE) &&
3146	    !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3147		btrfs_info(fs_info, "creating free space tree");
3148		ret = btrfs_create_free_space_tree(fs_info);
3149		if (ret) {
3150			btrfs_warn(fs_info,
3151				"failed to create free space tree: %d", ret);
3152			goto out;
3153		}
3154	}
3155
3156	if (cache_opt != btrfs_free_space_cache_v1_active(fs_info)) {
3157		ret = btrfs_set_free_space_cache_v1_active(fs_info, cache_opt);
3158		if (ret)
3159			goto out;
3160	}
3161
3162	ret = btrfs_resume_balance_async(fs_info);
3163	if (ret)
3164		goto out;
3165
3166	ret = btrfs_resume_dev_replace_async(fs_info);
3167	if (ret) {
3168		btrfs_warn(fs_info, "failed to resume dev_replace");
3169		goto out;
3170	}
3171
3172	btrfs_qgroup_rescan_resume(fs_info);
3173
3174	if (!fs_info->uuid_root) {
3175		btrfs_info(fs_info, "creating UUID tree");
3176		ret = btrfs_create_uuid_tree(fs_info);
3177		if (ret) {
3178			btrfs_warn(fs_info,
3179				   "failed to create the UUID tree %d", ret);
3180			goto out;
3181		}
3182	}
3183
3184out:
3185	return ret;
3186}
3187
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3188int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_devices,
3189		      char *options)
3190{
3191	u32 sectorsize;
3192	u32 nodesize;
3193	u32 stripesize;
3194	u64 generation;
3195	u64 features;
3196	u16 csum_type;
3197	struct btrfs_super_block *disk_super;
3198	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
3199	struct btrfs_root *tree_root;
3200	struct btrfs_root *chunk_root;
3201	int ret;
3202	int err = -EINVAL;
3203	int level;
3204
3205	ret = init_mount_fs_info(fs_info, sb);
3206	if (ret) {
3207		err = ret;
3208		goto fail;
3209	}
3210
3211	/* These need to be init'ed before we start creating inodes and such. */
3212	tree_root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID,
3213				     GFP_KERNEL);
3214	fs_info->tree_root = tree_root;
3215	chunk_root = btrfs_alloc_root(fs_info, BTRFS_CHUNK_TREE_OBJECTID,
3216				      GFP_KERNEL);
3217	fs_info->chunk_root = chunk_root;
3218	if (!tree_root || !chunk_root) {
3219		err = -ENOMEM;
3220		goto fail;
3221	}
3222
3223	fs_info->btree_inode = new_inode(sb);
3224	if (!fs_info->btree_inode) {
3225		err = -ENOMEM;
3226		goto fail;
3227	}
3228	mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
3229	btrfs_init_btree_inode(fs_info);
3230
3231	invalidate_bdev(fs_devices->latest_bdev);
3232
3233	/*
3234	 * Read super block and check the signature bytes only
3235	 */
3236	disk_super = btrfs_read_dev_super(fs_devices->latest_bdev);
3237	if (IS_ERR(disk_super)) {
3238		err = PTR_ERR(disk_super);
3239		goto fail_alloc;
3240	}
3241
 
3242	/*
3243	 * Verify the type first, if that or the checksum value are
3244	 * corrupted, we'll find out
3245	 */
3246	csum_type = btrfs_super_csum_type(disk_super);
3247	if (!btrfs_supported_super_csum(csum_type)) {
3248		btrfs_err(fs_info, "unsupported checksum algorithm: %u",
3249			  csum_type);
3250		err = -EINVAL;
3251		btrfs_release_disk_super(disk_super);
3252		goto fail_alloc;
3253	}
3254
3255	fs_info->csum_size = btrfs_super_csum_size(disk_super);
3256
3257	ret = btrfs_init_csum_hash(fs_info, csum_type);
3258	if (ret) {
3259		err = ret;
3260		btrfs_release_disk_super(disk_super);
3261		goto fail_alloc;
3262	}
3263
3264	/*
3265	 * We want to check superblock checksum, the type is stored inside.
3266	 * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k).
3267	 */
3268	if (btrfs_check_super_csum(fs_info, (u8 *)disk_super)) {
3269		btrfs_err(fs_info, "superblock checksum mismatch");
3270		err = -EINVAL;
3271		btrfs_release_disk_super(disk_super);
3272		goto fail_alloc;
3273	}
3274
3275	/*
3276	 * super_copy is zeroed at allocation time and we never touch the
3277	 * following bytes up to INFO_SIZE, the checksum is calculated from
3278	 * the whole block of INFO_SIZE
3279	 */
3280	memcpy(fs_info->super_copy, disk_super, sizeof(*fs_info->super_copy));
3281	btrfs_release_disk_super(disk_super);
3282
3283	disk_super = fs_info->super_copy;
3284
3285
3286	features = btrfs_super_flags(disk_super);
3287	if (features & BTRFS_SUPER_FLAG_CHANGING_FSID_V2) {
3288		features &= ~BTRFS_SUPER_FLAG_CHANGING_FSID_V2;
3289		btrfs_set_super_flags(disk_super, features);
3290		btrfs_info(fs_info,
3291			"found metadata UUID change in progress flag, clearing");
3292	}
3293
3294	memcpy(fs_info->super_for_commit, fs_info->super_copy,
3295	       sizeof(*fs_info->super_for_commit));
3296
3297	ret = btrfs_validate_mount_super(fs_info);
3298	if (ret) {
3299		btrfs_err(fs_info, "superblock contains fatal errors");
3300		err = -EINVAL;
3301		goto fail_alloc;
3302	}
3303
3304	if (!btrfs_super_root(disk_super))
 
 
3305		goto fail_alloc;
 
3306
3307	/* check FS state, whether FS is broken. */
3308	if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
3309		set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state);
3310
3311	/*
3312	 * In the long term, we'll store the compression type in the super
3313	 * block, and it'll be used for per file compression control.
3314	 */
3315	fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
3316
3317	/*
3318	 * Flag our filesystem as having big metadata blocks if they are bigger
3319	 * than the page size.
3320	 */
3321	if (btrfs_super_nodesize(disk_super) > PAGE_SIZE) {
3322		if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA))
3323			btrfs_info(fs_info,
3324				"flagging fs with big metadata feature");
3325		features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
3326	}
3327
3328	/* Set up fs_info before parsing mount options */
3329	nodesize = btrfs_super_nodesize(disk_super);
3330	sectorsize = btrfs_super_sectorsize(disk_super);
3331	stripesize = sectorsize;
3332	fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids));
3333	fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
3334
3335	fs_info->nodesize = nodesize;
3336	fs_info->sectorsize = sectorsize;
3337	fs_info->sectorsize_bits = ilog2(sectorsize);
3338	fs_info->csums_per_leaf = BTRFS_MAX_ITEM_SIZE(fs_info) / fs_info->csum_size;
3339	fs_info->stripesize = stripesize;
3340
3341	ret = btrfs_parse_options(fs_info, options, sb->s_flags);
3342	if (ret) {
3343		err = ret;
3344		goto fail_alloc;
3345	}
3346
3347	features = btrfs_super_incompat_flags(disk_super) &
3348		~BTRFS_FEATURE_INCOMPAT_SUPP;
3349	if (features) {
3350		btrfs_err(fs_info,
3351		    "cannot mount because of unsupported optional features (%llx)",
3352		    features);
3353		err = -EINVAL;
3354		goto fail_alloc;
3355	}
3356
3357	features = btrfs_super_incompat_flags(disk_super);
3358	features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
3359	if (fs_info->compress_type == BTRFS_COMPRESS_LZO)
3360		features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
3361	else if (fs_info->compress_type == BTRFS_COMPRESS_ZSTD)
3362		features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD;
3363
3364	if (features & BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA)
3365		btrfs_info(fs_info, "has skinny extents");
3366
3367	/*
3368	 * mixed block groups end up with duplicate but slightly offset
3369	 * extent buffers for the same range.  It leads to corruptions
3370	 */
3371	if ((features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
3372	    (sectorsize != nodesize)) {
3373		btrfs_err(fs_info,
3374"unequal nodesize/sectorsize (%u != %u) are not allowed for mixed block groups",
3375			nodesize, sectorsize);
3376		goto fail_alloc;
3377	}
3378
3379	/*
3380	 * Needn't use the lock because there is no other task which will
3381	 * update the flag.
3382	 */
3383	btrfs_set_super_incompat_flags(disk_super, features);
3384
3385	features = btrfs_super_compat_ro_flags(disk_super) &
3386		~BTRFS_FEATURE_COMPAT_RO_SUPP;
3387	if (!sb_rdonly(sb) && features) {
3388		btrfs_err(fs_info,
3389	"cannot mount read-write because of unsupported optional features (%llx)",
3390		       features);
3391		err = -EINVAL;
3392		goto fail_alloc;
3393	}
3394
3395	/* For 4K sector size support, it's only read-only */
3396	if (PAGE_SIZE == SZ_64K && sectorsize == SZ_4K) {
3397		if (!sb_rdonly(sb) || btrfs_super_log_root(disk_super)) {
3398			btrfs_err(fs_info,
3399	"subpage sectorsize %u only supported read-only for page size %lu",
3400				sectorsize, PAGE_SIZE);
3401			err = -EINVAL;
3402			goto fail_alloc;
3403		}
 
 
3404	}
3405
3406	ret = btrfs_init_workqueues(fs_info, fs_devices);
3407	if (ret) {
3408		err = ret;
3409		goto fail_sb_buffer;
3410	}
3411
3412	sb->s_bdi->ra_pages *= btrfs_super_num_devices(disk_super);
3413	sb->s_bdi->ra_pages = max(sb->s_bdi->ra_pages, SZ_4M / PAGE_SIZE);
3414
3415	sb->s_blocksize = sectorsize;
3416	sb->s_blocksize_bits = blksize_bits(sectorsize);
3417	memcpy(&sb->s_uuid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE);
3418
3419	mutex_lock(&fs_info->chunk_mutex);
3420	ret = btrfs_read_sys_array(fs_info);
3421	mutex_unlock(&fs_info->chunk_mutex);
3422	if (ret) {
3423		btrfs_err(fs_info, "failed to read the system array: %d", ret);
3424		goto fail_sb_buffer;
3425	}
3426
3427	generation = btrfs_super_chunk_root_generation(disk_super);
3428	level = btrfs_super_chunk_root_level(disk_super);
3429
3430	chunk_root->node = read_tree_block(fs_info,
3431					   btrfs_super_chunk_root(disk_super),
3432					   BTRFS_CHUNK_TREE_OBJECTID,
3433					   generation, level, NULL);
3434	if (IS_ERR(chunk_root->node) ||
3435	    !extent_buffer_uptodate(chunk_root->node)) {
3436		btrfs_err(fs_info, "failed to read chunk root");
3437		if (!IS_ERR(chunk_root->node))
3438			free_extent_buffer(chunk_root->node);
3439		chunk_root->node = NULL;
3440		goto fail_tree_roots;
3441	}
3442	btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
3443	chunk_root->commit_root = btrfs_root_node(chunk_root);
3444
3445	read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
3446			   offsetof(struct btrfs_header, chunk_tree_uuid),
3447			   BTRFS_UUID_SIZE);
3448
3449	ret = btrfs_read_chunk_tree(fs_info);
3450	if (ret) {
3451		btrfs_err(fs_info, "failed to read chunk tree: %d", ret);
3452		goto fail_tree_roots;
3453	}
3454
3455	/*
3456	 * At this point we know all the devices that make this filesystem,
3457	 * including the seed devices but we don't know yet if the replace
3458	 * target is required. So free devices that are not part of this
3459	 * filesystem but skip the replace target device which is checked
3460	 * below in btrfs_init_dev_replace().
3461	 */
3462	btrfs_free_extra_devids(fs_devices);
3463	if (!fs_devices->latest_bdev) {
3464		btrfs_err(fs_info, "failed to read devices");
 
3465		goto fail_tree_roots;
3466	}
3467
3468	ret = init_tree_roots(fs_info);
3469	if (ret)
3470		goto fail_tree_roots;
3471
3472	/*
3473	 * Get zone type information of zoned block devices. This will also
3474	 * handle emulation of a zoned filesystem if a regular device has the
3475	 * zoned incompat feature flag set.
3476	 */
3477	ret = btrfs_get_dev_zone_info_all_devices(fs_info);
3478	if (ret) {
3479		btrfs_err(fs_info,
3480			  "zoned: failed to read device zone info: %d",
3481			  ret);
3482		goto fail_block_groups;
3483	}
3484
3485	/*
3486	 * If we have a uuid root and we're not being told to rescan we need to
3487	 * check the generation here so we can set the
3488	 * BTRFS_FS_UPDATE_UUID_TREE_GEN bit.  Otherwise we could commit the
3489	 * transaction during a balance or the log replay without updating the
3490	 * uuid generation, and then if we crash we would rescan the uuid tree,
3491	 * even though it was perfectly fine.
3492	 */
3493	if (fs_info->uuid_root && !btrfs_test_opt(fs_info, RESCAN_UUID_TREE) &&
3494	    fs_info->generation == btrfs_super_uuid_tree_generation(disk_super))
3495		set_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags);
3496
3497	ret = btrfs_verify_dev_extents(fs_info);
3498	if (ret) {
3499		btrfs_err(fs_info,
3500			  "failed to verify dev extents against chunks: %d",
3501			  ret);
3502		goto fail_block_groups;
3503	}
3504	ret = btrfs_recover_balance(fs_info);
3505	if (ret) {
3506		btrfs_err(fs_info, "failed to recover balance: %d", ret);
3507		goto fail_block_groups;
3508	}
3509
3510	ret = btrfs_init_dev_stats(fs_info);
3511	if (ret) {
3512		btrfs_err(fs_info, "failed to init dev_stats: %d", ret);
3513		goto fail_block_groups;
3514	}
3515
3516	ret = btrfs_init_dev_replace(fs_info);
3517	if (ret) {
3518		btrfs_err(fs_info, "failed to init dev_replace: %d", ret);
3519		goto fail_block_groups;
3520	}
3521
3522	ret = btrfs_check_zoned_mode(fs_info);
3523	if (ret) {
3524		btrfs_err(fs_info, "failed to initialize zoned mode: %d",
3525			  ret);
3526		goto fail_block_groups;
3527	}
3528
3529	ret = btrfs_sysfs_add_fsid(fs_devices);
3530	if (ret) {
3531		btrfs_err(fs_info, "failed to init sysfs fsid interface: %d",
3532				ret);
3533		goto fail_block_groups;
3534	}
3535
3536	ret = btrfs_sysfs_add_mounted(fs_info);
3537	if (ret) {
3538		btrfs_err(fs_info, "failed to init sysfs interface: %d", ret);
3539		goto fail_fsdev_sysfs;
3540	}
3541
3542	ret = btrfs_init_space_info(fs_info);
3543	if (ret) {
3544		btrfs_err(fs_info, "failed to initialize space info: %d", ret);
3545		goto fail_sysfs;
3546	}
3547
3548	ret = btrfs_read_block_groups(fs_info);
3549	if (ret) {
3550		btrfs_err(fs_info, "failed to read block groups: %d", ret);
3551		goto fail_sysfs;
3552	}
3553
3554	if (!sb_rdonly(sb) && !btrfs_check_rw_degradable(fs_info, NULL)) {
 
 
 
 
 
3555		btrfs_warn(fs_info,
3556		"writable mount is not allowed due to too many missing devices");
 
3557		goto fail_sysfs;
3558	}
3559
3560	fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
3561					       "btrfs-cleaner");
3562	if (IS_ERR(fs_info->cleaner_kthread))
 
3563		goto fail_sysfs;
 
3564
3565	fs_info->transaction_kthread = kthread_run(transaction_kthread,
3566						   tree_root,
3567						   "btrfs-transaction");
3568	if (IS_ERR(fs_info->transaction_kthread))
 
3569		goto fail_cleaner;
3570
3571	if (!btrfs_test_opt(fs_info, NOSSD) &&
3572	    !fs_info->fs_devices->rotating) {
3573		btrfs_set_and_info(fs_info, SSD, "enabling ssd optimizations");
3574	}
3575
3576	/*
3577	 * Mount does not set all options immediately, we can do it now and do
3578	 * not have to wait for transaction commit
3579	 */
3580	btrfs_apply_pending_changes(fs_info);
3581
3582#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3583	if (btrfs_test_opt(fs_info, CHECK_INTEGRITY)) {
3584		ret = btrfsic_mount(fs_info, fs_devices,
3585				    btrfs_test_opt(fs_info,
3586					CHECK_INTEGRITY_DATA) ? 1 : 0,
3587				    fs_info->check_integrity_print_mask);
3588		if (ret)
3589			btrfs_warn(fs_info,
3590				"failed to initialize integrity check module: %d",
3591				ret);
3592	}
3593#endif
3594	ret = btrfs_read_qgroup_config(fs_info);
3595	if (ret)
3596		goto fail_trans_kthread;
3597
3598	if (btrfs_build_ref_tree(fs_info))
3599		btrfs_err(fs_info, "couldn't build ref tree");
3600
3601	/* do not make disk changes in broken FS or nologreplay is given */
3602	if (btrfs_super_log_root(disk_super) != 0 &&
3603	    !btrfs_test_opt(fs_info, NOLOGREPLAY)) {
3604		btrfs_info(fs_info, "start tree-log replay");
3605		ret = btrfs_replay_log(fs_info, fs_devices);
3606		if (ret) {
3607			err = ret;
3608			goto fail_qgroup;
3609		}
3610	}
3611
3612	fs_info->fs_root = btrfs_get_fs_root(fs_info, BTRFS_FS_TREE_OBJECTID, true);
3613	if (IS_ERR(fs_info->fs_root)) {
3614		err = PTR_ERR(fs_info->fs_root);
3615		btrfs_warn(fs_info, "failed to read fs tree: %d", err);
3616		fs_info->fs_root = NULL;
3617		goto fail_qgroup;
3618	}
3619
3620	if (sb_rdonly(sb))
3621		goto clear_oneshot;
3622
3623	ret = btrfs_start_pre_rw_mount(fs_info);
3624	if (ret) {
3625		close_ctree(fs_info);
3626		return ret;
3627	}
3628	btrfs_discard_resume(fs_info);
3629
3630	if (fs_info->uuid_root &&
3631	    (btrfs_test_opt(fs_info, RESCAN_UUID_TREE) ||
3632	     fs_info->generation != btrfs_super_uuid_tree_generation(disk_super))) {
3633		btrfs_info(fs_info, "checking UUID tree");
3634		ret = btrfs_check_uuid_tree(fs_info);
3635		if (ret) {
3636			btrfs_warn(fs_info,
3637				"failed to check the UUID tree: %d", ret);
3638			close_ctree(fs_info);
3639			return ret;
3640		}
3641	}
3642
3643	set_bit(BTRFS_FS_OPEN, &fs_info->flags);
3644
3645clear_oneshot:
3646	btrfs_clear_oneshot_options(fs_info);
 
 
3647	return 0;
3648
3649fail_qgroup:
3650	btrfs_free_qgroup_config(fs_info);
3651fail_trans_kthread:
3652	kthread_stop(fs_info->transaction_kthread);
3653	btrfs_cleanup_transaction(fs_info);
3654	btrfs_free_fs_roots(fs_info);
3655fail_cleaner:
3656	kthread_stop(fs_info->cleaner_kthread);
3657
3658	/*
3659	 * make sure we're done with the btree inode before we stop our
3660	 * kthreads
3661	 */
3662	filemap_write_and_wait(fs_info->btree_inode->i_mapping);
3663
3664fail_sysfs:
3665	btrfs_sysfs_remove_mounted(fs_info);
3666
3667fail_fsdev_sysfs:
3668	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
3669
3670fail_block_groups:
3671	btrfs_put_block_group_cache(fs_info);
3672
3673fail_tree_roots:
3674	if (fs_info->data_reloc_root)
3675		btrfs_drop_and_free_fs_root(fs_info, fs_info->data_reloc_root);
3676	free_root_pointers(fs_info, true);
3677	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
3678
3679fail_sb_buffer:
3680	btrfs_stop_all_workers(fs_info);
3681	btrfs_free_block_groups(fs_info);
3682fail_alloc:
3683	btrfs_mapping_tree_free(&fs_info->mapping_tree);
3684
3685	iput(fs_info->btree_inode);
3686fail:
3687	btrfs_close_devices(fs_info->fs_devices);
3688	return err;
 
3689}
3690ALLOW_ERROR_INJECTION(open_ctree, ERRNO);
3691
3692static void btrfs_end_super_write(struct bio *bio)
3693{
3694	struct btrfs_device *device = bio->bi_private;
3695	struct bio_vec *bvec;
3696	struct bvec_iter_all iter_all;
3697	struct page *page;
3698
3699	bio_for_each_segment_all(bvec, bio, iter_all) {
3700		page = bvec->bv_page;
3701
3702		if (bio->bi_status) {
3703			btrfs_warn_rl_in_rcu(device->fs_info,
3704				"lost page write due to IO error on %s (%d)",
3705				rcu_str_deref(device->name),
3706				blk_status_to_errno(bio->bi_status));
3707			ClearPageUptodate(page);
3708			SetPageError(page);
3709			btrfs_dev_stat_inc_and_print(device,
3710						     BTRFS_DEV_STAT_WRITE_ERRS);
3711		} else {
3712			SetPageUptodate(page);
3713		}
3714
3715		put_page(page);
3716		unlock_page(page);
3717	}
3718
3719	bio_put(bio);
3720}
3721
3722struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
3723						   int copy_num)
3724{
3725	struct btrfs_super_block *super;
3726	struct page *page;
3727	u64 bytenr, bytenr_orig;
3728	struct address_space *mapping = bdev->bd_inode->i_mapping;
3729	int ret;
3730
3731	bytenr_orig = btrfs_sb_offset(copy_num);
3732	ret = btrfs_sb_log_location_bdev(bdev, copy_num, READ, &bytenr);
3733	if (ret == -ENOENT)
3734		return ERR_PTR(-EINVAL);
3735	else if (ret)
3736		return ERR_PTR(ret);
3737
3738	if (bytenr + BTRFS_SUPER_INFO_SIZE >= i_size_read(bdev->bd_inode))
3739		return ERR_PTR(-EINVAL);
3740
 
 
 
 
 
 
 
 
 
 
 
 
 
3741	page = read_cache_page_gfp(mapping, bytenr >> PAGE_SHIFT, GFP_NOFS);
3742	if (IS_ERR(page))
3743		return ERR_CAST(page);
3744
3745	super = page_address(page);
3746	if (btrfs_super_magic(super) != BTRFS_MAGIC) {
3747		btrfs_release_disk_super(super);
3748		return ERR_PTR(-ENODATA);
3749	}
3750
3751	if (btrfs_super_bytenr(super) != bytenr_orig) {
3752		btrfs_release_disk_super(super);
3753		return ERR_PTR(-EINVAL);
3754	}
3755
3756	return super;
3757}
3758
3759
3760struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev)
3761{
3762	struct btrfs_super_block *super, *latest = NULL;
3763	int i;
3764	u64 transid = 0;
3765
3766	/* we would like to check all the supers, but that would make
3767	 * a btrfs mount succeed after a mkfs from a different FS.
3768	 * So, we need to add a special mount option to scan for
3769	 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
3770	 */
3771	for (i = 0; i < 1; i++) {
3772		super = btrfs_read_dev_one_super(bdev, i);
3773		if (IS_ERR(super))
3774			continue;
3775
3776		if (!latest || btrfs_super_generation(super) > transid) {
3777			if (latest)
3778				btrfs_release_disk_super(super);
3779
3780			latest = super;
3781			transid = btrfs_super_generation(super);
3782		}
3783	}
3784
3785	return super;
3786}
3787
3788/*
3789 * Write superblock @sb to the @device. Do not wait for completion, all the
3790 * pages we use for writing are locked.
3791 *
3792 * Write @max_mirrors copies of the superblock, where 0 means default that fit
3793 * the expected device size at commit time. Note that max_mirrors must be
3794 * same for write and wait phases.
3795 *
3796 * Return number of errors when page is not found or submission fails.
3797 */
3798static int write_dev_supers(struct btrfs_device *device,
3799			    struct btrfs_super_block *sb, int max_mirrors)
3800{
3801	struct btrfs_fs_info *fs_info = device->fs_info;
3802	struct address_space *mapping = device->bdev->bd_inode->i_mapping;
3803	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
3804	int i;
3805	int errors = 0;
3806	int ret;
3807	u64 bytenr, bytenr_orig;
3808
3809	if (max_mirrors == 0)
3810		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
3811
3812	shash->tfm = fs_info->csum_shash;
3813
3814	for (i = 0; i < max_mirrors; i++) {
3815		struct page *page;
3816		struct bio *bio;
3817		struct btrfs_super_block *disk_super;
3818
3819		bytenr_orig = btrfs_sb_offset(i);
3820		ret = btrfs_sb_log_location(device, i, WRITE, &bytenr);
3821		if (ret == -ENOENT) {
3822			continue;
3823		} else if (ret < 0) {
3824			btrfs_err(device->fs_info,
3825				"couldn't get super block location for mirror %d",
3826				i);
3827			errors++;
3828			continue;
3829		}
3830		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
3831		    device->commit_total_bytes)
3832			break;
3833
3834		btrfs_set_super_bytenr(sb, bytenr_orig);
3835
3836		crypto_shash_digest(shash, (const char *)sb + BTRFS_CSUM_SIZE,
3837				    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE,
3838				    sb->csum);
3839
3840		page = find_or_create_page(mapping, bytenr >> PAGE_SHIFT,
3841					   GFP_NOFS);
3842		if (!page) {
3843			btrfs_err(device->fs_info,
3844			    "couldn't get super block page for bytenr %llu",
3845			    bytenr);
3846			errors++;
3847			continue;
3848		}
3849
3850		/* Bump the refcount for wait_dev_supers() */
3851		get_page(page);
3852
3853		disk_super = page_address(page);
3854		memcpy(disk_super, sb, BTRFS_SUPER_INFO_SIZE);
3855
3856		/*
3857		 * Directly use bios here instead of relying on the page cache
3858		 * to do I/O, so we don't lose the ability to do integrity
3859		 * checking.
3860		 */
3861		bio = bio_alloc(GFP_NOFS, 1);
3862		bio_set_dev(bio, device->bdev);
 
3863		bio->bi_iter.bi_sector = bytenr >> SECTOR_SHIFT;
3864		bio->bi_private = device;
3865		bio->bi_end_io = btrfs_end_super_write;
3866		__bio_add_page(bio, page, BTRFS_SUPER_INFO_SIZE,
3867			       offset_in_page(bytenr));
3868
3869		/*
3870		 * We FUA only the first super block.  The others we allow to
3871		 * go down lazy and there's a short window where the on-disk
3872		 * copies might still contain the older version.
3873		 */
3874		bio->bi_opf = REQ_OP_WRITE | REQ_SYNC | REQ_META | REQ_PRIO;
3875		if (i == 0 && !btrfs_test_opt(device->fs_info, NOBARRIER))
3876			bio->bi_opf |= REQ_FUA;
 
3877
3878		btrfsic_submit_bio(bio);
3879		btrfs_advance_sb_log(device, i);
3880	}
3881	return errors < i ? 0 : -1;
3882}
3883
3884/*
3885 * Wait for write completion of superblocks done by write_dev_supers,
3886 * @max_mirrors same for write and wait phases.
3887 *
3888 * Return number of errors when page is not found or not marked up to
3889 * date.
3890 */
3891static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
3892{
3893	int i;
3894	int errors = 0;
3895	bool primary_failed = false;
3896	int ret;
3897	u64 bytenr;
3898
3899	if (max_mirrors == 0)
3900		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
3901
3902	for (i = 0; i < max_mirrors; i++) {
3903		struct page *page;
3904
3905		ret = btrfs_sb_log_location(device, i, READ, &bytenr);
3906		if (ret == -ENOENT) {
3907			break;
3908		} else if (ret < 0) {
3909			errors++;
3910			if (i == 0)
3911				primary_failed = true;
3912			continue;
3913		}
3914		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
3915		    device->commit_total_bytes)
3916			break;
3917
3918		page = find_get_page(device->bdev->bd_inode->i_mapping,
3919				     bytenr >> PAGE_SHIFT);
3920		if (!page) {
3921			errors++;
3922			if (i == 0)
3923				primary_failed = true;
3924			continue;
3925		}
3926		/* Page is submitted locked and unlocked once the IO completes */
3927		wait_on_page_locked(page);
3928		if (PageError(page)) {
3929			errors++;
3930			if (i == 0)
3931				primary_failed = true;
3932		}
3933
3934		/* Drop our reference */
3935		put_page(page);
3936
3937		/* Drop the reference from the writing run */
3938		put_page(page);
3939	}
3940
3941	/* log error, force error return */
3942	if (primary_failed) {
3943		btrfs_err(device->fs_info, "error writing primary super block to device %llu",
3944			  device->devid);
3945		return -1;
3946	}
3947
3948	return errors < i ? 0 : -1;
3949}
3950
3951/*
3952 * endio for the write_dev_flush, this will wake anyone waiting
3953 * for the barrier when it is done
3954 */
3955static void btrfs_end_empty_barrier(struct bio *bio)
3956{
 
3957	complete(bio->bi_private);
3958}
3959
3960/*
3961 * Submit a flush request to the device if it supports it. Error handling is
3962 * done in the waiting counterpart.
3963 */
3964static void write_dev_flush(struct btrfs_device *device)
3965{
3966	struct request_queue *q = bdev_get_queue(device->bdev);
3967	struct bio *bio = device->flush_bio;
3968
3969	if (!test_bit(QUEUE_FLAG_WC, &q->queue_flags))
3970		return;
3971
3972	bio_reset(bio);
 
3973	bio->bi_end_io = btrfs_end_empty_barrier;
3974	bio_set_dev(bio, device->bdev);
3975	bio->bi_opf = REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH;
3976	init_completion(&device->flush_wait);
3977	bio->bi_private = &device->flush_wait;
3978
3979	btrfsic_submit_bio(bio);
3980	set_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
3981}
3982
3983/*
3984 * If the flush bio has been submitted by write_dev_flush, wait for it.
 
3985 */
3986static blk_status_t wait_dev_flush(struct btrfs_device *device)
3987{
3988	struct bio *bio = device->flush_bio;
3989
3990	if (!test_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state))
3991		return BLK_STS_OK;
3992
3993	clear_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
3994	wait_for_completion_io(&device->flush_wait);
3995
3996	return bio->bi_status;
3997}
 
 
 
3998
3999static int check_barrier_error(struct btrfs_fs_info *fs_info)
4000{
4001	if (!btrfs_check_rw_degradable(fs_info, NULL))
4002		return -EIO;
4003	return 0;
4004}
4005
4006/*
4007 * send an empty flush down to each device in parallel,
4008 * then wait for them
4009 */
4010static int barrier_all_devices(struct btrfs_fs_info *info)
4011{
4012	struct list_head *head;
4013	struct btrfs_device *dev;
4014	int errors_wait = 0;
4015	blk_status_t ret;
4016
4017	lockdep_assert_held(&info->fs_devices->device_list_mutex);
4018	/* send down all the barriers */
4019	head = &info->fs_devices->devices;
4020	list_for_each_entry(dev, head, dev_list) {
4021		if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
4022			continue;
4023		if (!dev->bdev)
4024			continue;
4025		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4026		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4027			continue;
4028
4029		write_dev_flush(dev);
4030		dev->last_flush_error = BLK_STS_OK;
4031	}
4032
4033	/* wait for all the barriers */
4034	list_for_each_entry(dev, head, dev_list) {
4035		if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
4036			continue;
4037		if (!dev->bdev) {
4038			errors_wait++;
4039			continue;
4040		}
4041		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4042		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4043			continue;
4044
4045		ret = wait_dev_flush(dev);
4046		if (ret) {
4047			dev->last_flush_error = ret;
4048			btrfs_dev_stat_inc_and_print(dev,
4049					BTRFS_DEV_STAT_FLUSH_ERRS);
4050			errors_wait++;
4051		}
4052	}
4053
4054	if (errors_wait) {
4055		/*
4056		 * At some point we need the status of all disks
4057		 * to arrive at the volume status. So error checking
4058		 * is being pushed to a separate loop.
4059		 */
4060		return check_barrier_error(info);
4061	}
4062	return 0;
4063}
4064
4065int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags)
4066{
4067	int raid_type;
4068	int min_tolerated = INT_MAX;
4069
4070	if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 ||
4071	    (flags & BTRFS_AVAIL_ALLOC_BIT_SINGLE))
4072		min_tolerated = min_t(int, min_tolerated,
4073				    btrfs_raid_array[BTRFS_RAID_SINGLE].
4074				    tolerated_failures);
4075
4076	for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
4077		if (raid_type == BTRFS_RAID_SINGLE)
4078			continue;
4079		if (!(flags & btrfs_raid_array[raid_type].bg_flag))
4080			continue;
4081		min_tolerated = min_t(int, min_tolerated,
4082				    btrfs_raid_array[raid_type].
4083				    tolerated_failures);
4084	}
4085
4086	if (min_tolerated == INT_MAX) {
4087		pr_warn("BTRFS: unknown raid flag: %llu", flags);
4088		min_tolerated = 0;
4089	}
4090
4091	return min_tolerated;
4092}
4093
4094int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors)
4095{
4096	struct list_head *head;
4097	struct btrfs_device *dev;
4098	struct btrfs_super_block *sb;
4099	struct btrfs_dev_item *dev_item;
4100	int ret;
4101	int do_barriers;
4102	int max_errors;
4103	int total_errors = 0;
4104	u64 flags;
4105
4106	do_barriers = !btrfs_test_opt(fs_info, NOBARRIER);
4107
4108	/*
4109	 * max_mirrors == 0 indicates we're from commit_transaction,
4110	 * not from fsync where the tree roots in fs_info have not
4111	 * been consistent on disk.
4112	 */
4113	if (max_mirrors == 0)
4114		backup_super_roots(fs_info);
4115
4116	sb = fs_info->super_for_commit;
4117	dev_item = &sb->dev_item;
4118
4119	mutex_lock(&fs_info->fs_devices->device_list_mutex);
4120	head = &fs_info->fs_devices->devices;
4121	max_errors = btrfs_super_num_devices(fs_info->super_copy) - 1;
4122
4123	if (do_barriers) {
4124		ret = barrier_all_devices(fs_info);
4125		if (ret) {
4126			mutex_unlock(
4127				&fs_info->fs_devices->device_list_mutex);
4128			btrfs_handle_fs_error(fs_info, ret,
4129					      "errors while submitting device barriers.");
4130			return ret;
4131		}
4132	}
4133
4134	list_for_each_entry(dev, head, dev_list) {
4135		if (!dev->bdev) {
4136			total_errors++;
4137			continue;
4138		}
4139		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4140		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4141			continue;
4142
4143		btrfs_set_stack_device_generation(dev_item, 0);
4144		btrfs_set_stack_device_type(dev_item, dev->type);
4145		btrfs_set_stack_device_id(dev_item, dev->devid);
4146		btrfs_set_stack_device_total_bytes(dev_item,
4147						   dev->commit_total_bytes);
4148		btrfs_set_stack_device_bytes_used(dev_item,
4149						  dev->commit_bytes_used);
4150		btrfs_set_stack_device_io_align(dev_item, dev->io_align);
4151		btrfs_set_stack_device_io_width(dev_item, dev->io_width);
4152		btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
4153		memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
4154		memcpy(dev_item->fsid, dev->fs_devices->metadata_uuid,
4155		       BTRFS_FSID_SIZE);
4156
4157		flags = btrfs_super_flags(sb);
4158		btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
4159
4160		ret = btrfs_validate_write_super(fs_info, sb);
4161		if (ret < 0) {
4162			mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4163			btrfs_handle_fs_error(fs_info, -EUCLEAN,
4164				"unexpected superblock corruption detected");
4165			return -EUCLEAN;
4166		}
4167
4168		ret = write_dev_supers(dev, sb, max_mirrors);
4169		if (ret)
4170			total_errors++;
4171	}
4172	if (total_errors > max_errors) {
4173		btrfs_err(fs_info, "%d errors while writing supers",
4174			  total_errors);
4175		mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4176
4177		/* FUA is masked off if unsupported and can't be the reason */
4178		btrfs_handle_fs_error(fs_info, -EIO,
4179				      "%d errors while writing supers",
4180				      total_errors);
4181		return -EIO;
4182	}
4183
4184	total_errors = 0;
4185	list_for_each_entry(dev, head, dev_list) {
4186		if (!dev->bdev)
4187			continue;
4188		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4189		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4190			continue;
4191
4192		ret = wait_dev_supers(dev, max_mirrors);
4193		if (ret)
4194			total_errors++;
4195	}
4196	mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4197	if (total_errors > max_errors) {
4198		btrfs_handle_fs_error(fs_info, -EIO,
4199				      "%d errors while writing supers",
4200				      total_errors);
4201		return -EIO;
4202	}
4203	return 0;
4204}
4205
4206/* Drop a fs root from the radix tree and free it. */
4207void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
4208				  struct btrfs_root *root)
4209{
4210	bool drop_ref = false;
4211
4212	spin_lock(&fs_info->fs_roots_radix_lock);
4213	radix_tree_delete(&fs_info->fs_roots_radix,
4214			  (unsigned long)root->root_key.objectid);
4215	if (test_and_clear_bit(BTRFS_ROOT_IN_RADIX, &root->state))
4216		drop_ref = true;
4217	spin_unlock(&fs_info->fs_roots_radix_lock);
4218
4219	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
4220		ASSERT(root->log_root == NULL);
4221		if (root->reloc_root) {
4222			btrfs_put_root(root->reloc_root);
4223			root->reloc_root = NULL;
4224		}
4225	}
4226
4227	if (drop_ref)
4228		btrfs_put_root(root);
4229}
4230
4231int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
4232{
4233	u64 root_objectid = 0;
4234	struct btrfs_root *gang[8];
4235	int i = 0;
4236	int err = 0;
4237	unsigned int ret = 0;
4238
4239	while (1) {
4240		spin_lock(&fs_info->fs_roots_radix_lock);
4241		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
4242					     (void **)gang, root_objectid,
4243					     ARRAY_SIZE(gang));
4244		if (!ret) {
4245			spin_unlock(&fs_info->fs_roots_radix_lock);
4246			break;
4247		}
4248		root_objectid = gang[ret - 1]->root_key.objectid + 1;
4249
4250		for (i = 0; i < ret; i++) {
4251			/* Avoid to grab roots in dead_roots */
4252			if (btrfs_root_refs(&gang[i]->root_item) == 0) {
4253				gang[i] = NULL;
4254				continue;
4255			}
4256			/* grab all the search result for later use */
4257			gang[i] = btrfs_grab_root(gang[i]);
4258		}
4259		spin_unlock(&fs_info->fs_roots_radix_lock);
4260
4261		for (i = 0; i < ret; i++) {
4262			if (!gang[i])
4263				continue;
4264			root_objectid = gang[i]->root_key.objectid;
4265			err = btrfs_orphan_cleanup(gang[i]);
4266			if (err)
4267				break;
4268			btrfs_put_root(gang[i]);
4269		}
4270		root_objectid++;
4271	}
4272
4273	/* release the uncleaned roots due to error */
4274	for (; i < ret; i++) {
4275		if (gang[i])
4276			btrfs_put_root(gang[i]);
4277	}
4278	return err;
4279}
4280
4281int btrfs_commit_super(struct btrfs_fs_info *fs_info)
4282{
4283	struct btrfs_root *root = fs_info->tree_root;
4284	struct btrfs_trans_handle *trans;
4285
4286	mutex_lock(&fs_info->cleaner_mutex);
4287	btrfs_run_delayed_iputs(fs_info);
4288	mutex_unlock(&fs_info->cleaner_mutex);
4289	wake_up_process(fs_info->cleaner_kthread);
4290
4291	/* wait until ongoing cleanup work done */
4292	down_write(&fs_info->cleanup_work_sem);
4293	up_write(&fs_info->cleanup_work_sem);
4294
4295	trans = btrfs_join_transaction(root);
4296	if (IS_ERR(trans))
4297		return PTR_ERR(trans);
4298	return btrfs_commit_transaction(trans);
4299}
4300
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4301void __cold close_ctree(struct btrfs_fs_info *fs_info)
4302{
4303	int ret;
4304
4305	set_bit(BTRFS_FS_CLOSING_START, &fs_info->flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4306	/*
4307	 * We don't want the cleaner to start new transactions, add more delayed
4308	 * iputs, etc. while we're closing. We can't use kthread_stop() yet
4309	 * because that frees the task_struct, and the transaction kthread might
4310	 * still try to wake up the cleaner.
4311	 */
4312	kthread_park(fs_info->cleaner_kthread);
4313
4314	/* wait for the qgroup rescan worker to stop */
4315	btrfs_qgroup_wait_for_completion(fs_info, false);
4316
4317	/* wait for the uuid_scan task to finish */
4318	down(&fs_info->uuid_tree_rescan_sem);
4319	/* avoid complains from lockdep et al., set sem back to initial state */
4320	up(&fs_info->uuid_tree_rescan_sem);
4321
4322	/* pause restriper - we want to resume on mount */
4323	btrfs_pause_balance(fs_info);
4324
4325	btrfs_dev_replace_suspend_for_unmount(fs_info);
4326
4327	btrfs_scrub_cancel(fs_info);
4328
4329	/* wait for any defraggers to finish */
4330	wait_event(fs_info->transaction_wait,
4331		   (atomic_read(&fs_info->defrag_running) == 0));
4332
4333	/* clear out the rbtree of defraggable inodes */
4334	btrfs_cleanup_defrag_inodes(fs_info);
4335
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4336	cancel_work_sync(&fs_info->async_reclaim_work);
4337	cancel_work_sync(&fs_info->async_data_reclaim_work);
4338	cancel_work_sync(&fs_info->preempt_reclaim_work);
4339
4340	cancel_work_sync(&fs_info->reclaim_bgs_work);
4341
4342	/* Cancel or finish ongoing discard work */
4343	btrfs_discard_cleanup(fs_info);
4344
4345	if (!sb_rdonly(fs_info->sb)) {
4346		/*
4347		 * The cleaner kthread is stopped, so do one final pass over
4348		 * unused block groups.
4349		 */
4350		btrfs_delete_unused_bgs(fs_info);
4351
4352		/*
4353		 * There might be existing delayed inode workers still running
4354		 * and holding an empty delayed inode item. We must wait for
4355		 * them to complete first because they can create a transaction.
4356		 * This happens when someone calls btrfs_balance_delayed_items()
4357		 * and then a transaction commit runs the same delayed nodes
4358		 * before any delayed worker has done something with the nodes.
4359		 * We must wait for any worker here and not at transaction
4360		 * commit time since that could cause a deadlock.
4361		 * This is a very rare case.
4362		 */
4363		btrfs_flush_workqueue(fs_info->delayed_workers);
4364
4365		ret = btrfs_commit_super(fs_info);
4366		if (ret)
4367			btrfs_err(fs_info, "commit super ret %d", ret);
4368	}
4369
4370	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state) ||
4371	    test_bit(BTRFS_FS_STATE_TRANS_ABORTED, &fs_info->fs_state))
4372		btrfs_error_commit_super(fs_info);
4373
4374	kthread_stop(fs_info->transaction_kthread);
4375	kthread_stop(fs_info->cleaner_kthread);
4376
4377	ASSERT(list_empty(&fs_info->delayed_iputs));
4378	set_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags);
4379
4380	if (btrfs_check_quota_leak(fs_info)) {
4381		WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
4382		btrfs_err(fs_info, "qgroup reserved space leaked");
4383	}
4384
4385	btrfs_free_qgroup_config(fs_info);
4386	ASSERT(list_empty(&fs_info->delalloc_roots));
4387
4388	if (percpu_counter_sum(&fs_info->delalloc_bytes)) {
4389		btrfs_info(fs_info, "at unmount delalloc count %lld",
4390		       percpu_counter_sum(&fs_info->delalloc_bytes));
4391	}
4392
4393	if (percpu_counter_sum(&fs_info->ordered_bytes))
4394		btrfs_info(fs_info, "at unmount dio bytes count %lld",
4395			   percpu_counter_sum(&fs_info->ordered_bytes));
4396
4397	btrfs_sysfs_remove_mounted(fs_info);
4398	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
4399
4400	btrfs_put_block_group_cache(fs_info);
4401
4402	/*
4403	 * we must make sure there is not any read request to
4404	 * submit after we stopping all workers.
4405	 */
4406	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
4407	btrfs_stop_all_workers(fs_info);
4408
4409	/* We shouldn't have any transaction open at this point */
4410	ASSERT(list_empty(&fs_info->trans_list));
4411
4412	clear_bit(BTRFS_FS_OPEN, &fs_info->flags);
4413	free_root_pointers(fs_info, true);
4414	btrfs_free_fs_roots(fs_info);
4415
4416	/*
4417	 * We must free the block groups after dropping the fs_roots as we could
4418	 * have had an IO error and have left over tree log blocks that aren't
4419	 * cleaned up until the fs roots are freed.  This makes the block group
4420	 * accounting appear to be wrong because there's pending reserved bytes,
4421	 * so make sure we do the block group cleanup afterwards.
4422	 */
4423	btrfs_free_block_groups(fs_info);
4424
4425	iput(fs_info->btree_inode);
4426
4427#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4428	if (btrfs_test_opt(fs_info, CHECK_INTEGRITY))
4429		btrfsic_unmount(fs_info->fs_devices);
4430#endif
4431
4432	btrfs_mapping_tree_free(&fs_info->mapping_tree);
4433	btrfs_close_devices(fs_info->fs_devices);
4434}
4435
4436int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
4437			  int atomic)
4438{
4439	int ret;
4440	struct inode *btree_inode = buf->pages[0]->mapping->host;
4441
4442	ret = extent_buffer_uptodate(buf);
4443	if (!ret)
4444		return ret;
4445
4446	ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
4447				    parent_transid, atomic);
4448	if (ret == -EAGAIN)
4449		return ret;
4450	return !ret;
4451}
4452
4453void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
4454{
4455	struct btrfs_fs_info *fs_info = buf->fs_info;
4456	u64 transid = btrfs_header_generation(buf);
4457	int was_dirty;
4458
4459#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4460	/*
4461	 * This is a fast path so only do this check if we have sanity tests
4462	 * enabled.  Normal people shouldn't be using unmapped buffers as dirty
4463	 * outside of the sanity tests.
4464	 */
4465	if (unlikely(test_bit(EXTENT_BUFFER_UNMAPPED, &buf->bflags)))
4466		return;
4467#endif
4468	btrfs_assert_tree_locked(buf);
4469	if (transid != fs_info->generation)
4470		WARN(1, KERN_CRIT "btrfs transid mismatch buffer %llu, found %llu running %llu\n",
4471			buf->start, transid, fs_info->generation);
4472	was_dirty = set_extent_buffer_dirty(buf);
4473	if (!was_dirty)
4474		percpu_counter_add_batch(&fs_info->dirty_metadata_bytes,
4475					 buf->len,
4476					 fs_info->dirty_metadata_batch);
4477#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4478	/*
4479	 * Since btrfs_mark_buffer_dirty() can be called with item pointer set
4480	 * but item data not updated.
4481	 * So here we should only check item pointers, not item data.
4482	 */
4483	if (btrfs_header_level(buf) == 0 &&
4484	    btrfs_check_leaf_relaxed(buf)) {
4485		btrfs_print_leaf(buf);
4486		ASSERT(0);
4487	}
4488#endif
4489}
4490
4491static void __btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info,
4492					int flush_delayed)
4493{
4494	/*
4495	 * looks as though older kernels can get into trouble with
4496	 * this code, they end up stuck in balance_dirty_pages forever
4497	 */
4498	int ret;
4499
4500	if (current->flags & PF_MEMALLOC)
4501		return;
4502
4503	if (flush_delayed)
4504		btrfs_balance_delayed_items(fs_info);
4505
4506	ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
4507				     BTRFS_DIRTY_METADATA_THRESH,
4508				     fs_info->dirty_metadata_batch);
4509	if (ret > 0) {
4510		balance_dirty_pages_ratelimited(fs_info->btree_inode->i_mapping);
4511	}
4512}
4513
4514void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info)
4515{
4516	__btrfs_btree_balance_dirty(fs_info, 1);
4517}
4518
4519void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info)
4520{
4521	__btrfs_btree_balance_dirty(fs_info, 0);
4522}
4523
4524int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level,
4525		      struct btrfs_key *first_key)
4526{
4527	return btree_read_extent_buffer_pages(buf, parent_transid,
4528					      level, first_key);
4529}
4530
4531static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info)
4532{
4533	/* cleanup FS via transaction */
4534	btrfs_cleanup_transaction(fs_info);
4535
4536	mutex_lock(&fs_info->cleaner_mutex);
4537	btrfs_run_delayed_iputs(fs_info);
4538	mutex_unlock(&fs_info->cleaner_mutex);
4539
4540	down_write(&fs_info->cleanup_work_sem);
4541	up_write(&fs_info->cleanup_work_sem);
4542}
4543
4544static void btrfs_drop_all_logs(struct btrfs_fs_info *fs_info)
4545{
4546	struct btrfs_root *gang[8];
4547	u64 root_objectid = 0;
4548	int ret;
4549
4550	spin_lock(&fs_info->fs_roots_radix_lock);
4551	while ((ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
4552					     (void **)gang, root_objectid,
4553					     ARRAY_SIZE(gang))) != 0) {
4554		int i;
4555
4556		for (i = 0; i < ret; i++)
4557			gang[i] = btrfs_grab_root(gang[i]);
4558		spin_unlock(&fs_info->fs_roots_radix_lock);
4559
4560		for (i = 0; i < ret; i++) {
4561			if (!gang[i])
4562				continue;
4563			root_objectid = gang[i]->root_key.objectid;
4564			btrfs_free_log(NULL, gang[i]);
4565			btrfs_put_root(gang[i]);
4566		}
4567		root_objectid++;
4568		spin_lock(&fs_info->fs_roots_radix_lock);
4569	}
4570	spin_unlock(&fs_info->fs_roots_radix_lock);
4571	btrfs_free_log_root_tree(NULL, fs_info);
4572}
4573
4574static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
4575{
4576	struct btrfs_ordered_extent *ordered;
4577
4578	spin_lock(&root->ordered_extent_lock);
4579	/*
4580	 * This will just short circuit the ordered completion stuff which will
4581	 * make sure the ordered extent gets properly cleaned up.
4582	 */
4583	list_for_each_entry(ordered, &root->ordered_extents,
4584			    root_extent_list)
4585		set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
4586	spin_unlock(&root->ordered_extent_lock);
4587}
4588
4589static void btrfs_destroy_all_ordered_extents(struct btrfs_fs_info *fs_info)
4590{
4591	struct btrfs_root *root;
4592	struct list_head splice;
4593
4594	INIT_LIST_HEAD(&splice);
4595
4596	spin_lock(&fs_info->ordered_root_lock);
4597	list_splice_init(&fs_info->ordered_roots, &splice);
4598	while (!list_empty(&splice)) {
4599		root = list_first_entry(&splice, struct btrfs_root,
4600					ordered_root);
4601		list_move_tail(&root->ordered_root,
4602			       &fs_info->ordered_roots);
4603
4604		spin_unlock(&fs_info->ordered_root_lock);
4605		btrfs_destroy_ordered_extents(root);
4606
4607		cond_resched();
4608		spin_lock(&fs_info->ordered_root_lock);
4609	}
4610	spin_unlock(&fs_info->ordered_root_lock);
4611
4612	/*
4613	 * We need this here because if we've been flipped read-only we won't
4614	 * get sync() from the umount, so we need to make sure any ordered
4615	 * extents that haven't had their dirty pages IO start writeout yet
4616	 * actually get run and error out properly.
4617	 */
4618	btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
4619}
4620
4621static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
4622				      struct btrfs_fs_info *fs_info)
4623{
4624	struct rb_node *node;
4625	struct btrfs_delayed_ref_root *delayed_refs;
4626	struct btrfs_delayed_ref_node *ref;
4627	int ret = 0;
4628
4629	delayed_refs = &trans->delayed_refs;
4630
4631	spin_lock(&delayed_refs->lock);
4632	if (atomic_read(&delayed_refs->num_entries) == 0) {
4633		spin_unlock(&delayed_refs->lock);
4634		btrfs_debug(fs_info, "delayed_refs has NO entry");
4635		return ret;
4636	}
4637
4638	while ((node = rb_first_cached(&delayed_refs->href_root)) != NULL) {
4639		struct btrfs_delayed_ref_head *head;
4640		struct rb_node *n;
4641		bool pin_bytes = false;
4642
4643		head = rb_entry(node, struct btrfs_delayed_ref_head,
4644				href_node);
4645		if (btrfs_delayed_ref_lock(delayed_refs, head))
4646			continue;
4647
4648		spin_lock(&head->lock);
4649		while ((n = rb_first_cached(&head->ref_tree)) != NULL) {
4650			ref = rb_entry(n, struct btrfs_delayed_ref_node,
4651				       ref_node);
4652			ref->in_tree = 0;
4653			rb_erase_cached(&ref->ref_node, &head->ref_tree);
4654			RB_CLEAR_NODE(&ref->ref_node);
4655			if (!list_empty(&ref->add_list))
4656				list_del(&ref->add_list);
4657			atomic_dec(&delayed_refs->num_entries);
4658			btrfs_put_delayed_ref(ref);
 
4659		}
4660		if (head->must_insert_reserved)
4661			pin_bytes = true;
4662		btrfs_free_delayed_extent_op(head->extent_op);
4663		btrfs_delete_ref_head(delayed_refs, head);
4664		spin_unlock(&head->lock);
4665		spin_unlock(&delayed_refs->lock);
4666		mutex_unlock(&head->mutex);
4667
4668		if (pin_bytes) {
4669			struct btrfs_block_group *cache;
4670
4671			cache = btrfs_lookup_block_group(fs_info, head->bytenr);
4672			BUG_ON(!cache);
4673
4674			spin_lock(&cache->space_info->lock);
4675			spin_lock(&cache->lock);
4676			cache->pinned += head->num_bytes;
4677			btrfs_space_info_update_bytes_pinned(fs_info,
4678				cache->space_info, head->num_bytes);
4679			cache->reserved -= head->num_bytes;
4680			cache->space_info->bytes_reserved -= head->num_bytes;
4681			spin_unlock(&cache->lock);
4682			spin_unlock(&cache->space_info->lock);
4683
4684			btrfs_put_block_group(cache);
4685
4686			btrfs_error_unpin_extent_range(fs_info, head->bytenr,
4687				head->bytenr + head->num_bytes - 1);
4688		}
4689		btrfs_cleanup_ref_head_accounting(fs_info, delayed_refs, head);
4690		btrfs_put_delayed_ref_head(head);
4691		cond_resched();
4692		spin_lock(&delayed_refs->lock);
4693	}
4694	btrfs_qgroup_destroy_extent_records(trans);
4695
4696	spin_unlock(&delayed_refs->lock);
4697
4698	return ret;
4699}
4700
4701static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
4702{
4703	struct btrfs_inode *btrfs_inode;
4704	struct list_head splice;
4705
4706	INIT_LIST_HEAD(&splice);
4707
4708	spin_lock(&root->delalloc_lock);
4709	list_splice_init(&root->delalloc_inodes, &splice);
4710
4711	while (!list_empty(&splice)) {
4712		struct inode *inode = NULL;
4713		btrfs_inode = list_first_entry(&splice, struct btrfs_inode,
4714					       delalloc_inodes);
4715		__btrfs_del_delalloc_inode(root, btrfs_inode);
4716		spin_unlock(&root->delalloc_lock);
4717
4718		/*
4719		 * Make sure we get a live inode and that it'll not disappear
4720		 * meanwhile.
4721		 */
4722		inode = igrab(&btrfs_inode->vfs_inode);
4723		if (inode) {
 
 
 
4724			invalidate_inode_pages2(inode->i_mapping);
 
4725			iput(inode);
4726		}
4727		spin_lock(&root->delalloc_lock);
4728	}
4729	spin_unlock(&root->delalloc_lock);
4730}
4731
4732static void btrfs_destroy_all_delalloc_inodes(struct btrfs_fs_info *fs_info)
4733{
4734	struct btrfs_root *root;
4735	struct list_head splice;
4736
4737	INIT_LIST_HEAD(&splice);
4738
4739	spin_lock(&fs_info->delalloc_root_lock);
4740	list_splice_init(&fs_info->delalloc_roots, &splice);
4741	while (!list_empty(&splice)) {
4742		root = list_first_entry(&splice, struct btrfs_root,
4743					 delalloc_root);
4744		root = btrfs_grab_root(root);
4745		BUG_ON(!root);
4746		spin_unlock(&fs_info->delalloc_root_lock);
4747
4748		btrfs_destroy_delalloc_inodes(root);
4749		btrfs_put_root(root);
4750
4751		spin_lock(&fs_info->delalloc_root_lock);
4752	}
4753	spin_unlock(&fs_info->delalloc_root_lock);
4754}
4755
4756static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
4757					struct extent_io_tree *dirty_pages,
4758					int mark)
4759{
4760	int ret;
4761	struct extent_buffer *eb;
4762	u64 start = 0;
4763	u64 end;
4764
4765	while (1) {
4766		ret = find_first_extent_bit(dirty_pages, start, &start, &end,
4767					    mark, NULL);
4768		if (ret)
4769			break;
4770
4771		clear_extent_bits(dirty_pages, start, end, mark);
4772		while (start <= end) {
4773			eb = find_extent_buffer(fs_info, start);
4774			start += fs_info->nodesize;
4775			if (!eb)
4776				continue;
 
 
4777			wait_on_extent_buffer_writeback(eb);
 
 
4778
4779			if (test_and_clear_bit(EXTENT_BUFFER_DIRTY,
4780					       &eb->bflags))
4781				clear_extent_buffer_dirty(eb);
4782			free_extent_buffer_stale(eb);
4783		}
4784	}
4785
4786	return ret;
4787}
4788
4789static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
4790				       struct extent_io_tree *unpin)
4791{
4792	u64 start;
4793	u64 end;
4794	int ret;
4795
4796	while (1) {
4797		struct extent_state *cached_state = NULL;
4798
4799		/*
4800		 * The btrfs_finish_extent_commit() may get the same range as
4801		 * ours between find_first_extent_bit and clear_extent_dirty.
4802		 * Hence, hold the unused_bg_unpin_mutex to avoid double unpin
4803		 * the same extent range.
4804		 */
4805		mutex_lock(&fs_info->unused_bg_unpin_mutex);
4806		ret = find_first_extent_bit(unpin, 0, &start, &end,
4807					    EXTENT_DIRTY, &cached_state);
4808		if (ret) {
4809			mutex_unlock(&fs_info->unused_bg_unpin_mutex);
4810			break;
4811		}
4812
4813		clear_extent_dirty(unpin, start, end, &cached_state);
4814		free_extent_state(cached_state);
4815		btrfs_error_unpin_extent_range(fs_info, start, end);
4816		mutex_unlock(&fs_info->unused_bg_unpin_mutex);
4817		cond_resched();
4818	}
4819
4820	return 0;
4821}
4822
4823static void btrfs_cleanup_bg_io(struct btrfs_block_group *cache)
4824{
4825	struct inode *inode;
4826
4827	inode = cache->io_ctl.inode;
4828	if (inode) {
 
 
 
4829		invalidate_inode_pages2(inode->i_mapping);
 
 
4830		BTRFS_I(inode)->generation = 0;
4831		cache->io_ctl.inode = NULL;
4832		iput(inode);
4833	}
4834	ASSERT(cache->io_ctl.pages == NULL);
4835	btrfs_put_block_group(cache);
4836}
4837
4838void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *cur_trans,
4839			     struct btrfs_fs_info *fs_info)
4840{
4841	struct btrfs_block_group *cache;
4842
4843	spin_lock(&cur_trans->dirty_bgs_lock);
4844	while (!list_empty(&cur_trans->dirty_bgs)) {
4845		cache = list_first_entry(&cur_trans->dirty_bgs,
4846					 struct btrfs_block_group,
4847					 dirty_list);
4848
4849		if (!list_empty(&cache->io_list)) {
4850			spin_unlock(&cur_trans->dirty_bgs_lock);
4851			list_del_init(&cache->io_list);
4852			btrfs_cleanup_bg_io(cache);
4853			spin_lock(&cur_trans->dirty_bgs_lock);
4854		}
4855
4856		list_del_init(&cache->dirty_list);
4857		spin_lock(&cache->lock);
4858		cache->disk_cache_state = BTRFS_DC_ERROR;
4859		spin_unlock(&cache->lock);
4860
4861		spin_unlock(&cur_trans->dirty_bgs_lock);
4862		btrfs_put_block_group(cache);
4863		btrfs_delayed_refs_rsv_release(fs_info, 1);
4864		spin_lock(&cur_trans->dirty_bgs_lock);
4865	}
4866	spin_unlock(&cur_trans->dirty_bgs_lock);
4867
4868	/*
4869	 * Refer to the definition of io_bgs member for details why it's safe
4870	 * to use it without any locking
4871	 */
4872	while (!list_empty(&cur_trans->io_bgs)) {
4873		cache = list_first_entry(&cur_trans->io_bgs,
4874					 struct btrfs_block_group,
4875					 io_list);
4876
4877		list_del_init(&cache->io_list);
4878		spin_lock(&cache->lock);
4879		cache->disk_cache_state = BTRFS_DC_ERROR;
4880		spin_unlock(&cache->lock);
4881		btrfs_cleanup_bg_io(cache);
4882	}
4883}
4884
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4885void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
4886				   struct btrfs_fs_info *fs_info)
4887{
4888	struct btrfs_device *dev, *tmp;
4889
4890	btrfs_cleanup_dirty_bgs(cur_trans, fs_info);
4891	ASSERT(list_empty(&cur_trans->dirty_bgs));
4892	ASSERT(list_empty(&cur_trans->io_bgs));
4893
4894	list_for_each_entry_safe(dev, tmp, &cur_trans->dev_update_list,
4895				 post_commit_list) {
4896		list_del_init(&dev->post_commit_list);
4897	}
4898
4899	btrfs_destroy_delayed_refs(cur_trans, fs_info);
4900
4901	cur_trans->state = TRANS_STATE_COMMIT_START;
4902	wake_up(&fs_info->transaction_blocked_wait);
4903
4904	cur_trans->state = TRANS_STATE_UNBLOCKED;
4905	wake_up(&fs_info->transaction_wait);
4906
4907	btrfs_destroy_delayed_inodes(fs_info);
4908
4909	btrfs_destroy_marked_extents(fs_info, &cur_trans->dirty_pages,
4910				     EXTENT_DIRTY);
4911	btrfs_destroy_pinned_extent(fs_info, &cur_trans->pinned_extents);
4912
4913	btrfs_free_redirty_list(cur_trans);
4914
4915	cur_trans->state =TRANS_STATE_COMPLETED;
4916	wake_up(&cur_trans->commit_wait);
4917}
4918
4919static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info)
4920{
4921	struct btrfs_transaction *t;
4922
4923	mutex_lock(&fs_info->transaction_kthread_mutex);
4924
4925	spin_lock(&fs_info->trans_lock);
4926	while (!list_empty(&fs_info->trans_list)) {
4927		t = list_first_entry(&fs_info->trans_list,
4928				     struct btrfs_transaction, list);
4929		if (t->state >= TRANS_STATE_COMMIT_START) {
4930			refcount_inc(&t->use_count);
4931			spin_unlock(&fs_info->trans_lock);
4932			btrfs_wait_for_commit(fs_info, t->transid);
4933			btrfs_put_transaction(t);
4934			spin_lock(&fs_info->trans_lock);
4935			continue;
4936		}
4937		if (t == fs_info->running_transaction) {
4938			t->state = TRANS_STATE_COMMIT_DOING;
4939			spin_unlock(&fs_info->trans_lock);
4940			/*
4941			 * We wait for 0 num_writers since we don't hold a trans
4942			 * handle open currently for this transaction.
4943			 */
4944			wait_event(t->writer_wait,
4945				   atomic_read(&t->num_writers) == 0);
4946		} else {
4947			spin_unlock(&fs_info->trans_lock);
4948		}
4949		btrfs_cleanup_one_transaction(t, fs_info);
4950
4951		spin_lock(&fs_info->trans_lock);
4952		if (t == fs_info->running_transaction)
4953			fs_info->running_transaction = NULL;
4954		list_del_init(&t->list);
4955		spin_unlock(&fs_info->trans_lock);
4956
4957		btrfs_put_transaction(t);
4958		trace_btrfs_transaction_commit(fs_info->tree_root);
4959		spin_lock(&fs_info->trans_lock);
4960	}
4961	spin_unlock(&fs_info->trans_lock);
4962	btrfs_destroy_all_ordered_extents(fs_info);
4963	btrfs_destroy_delayed_inodes(fs_info);
4964	btrfs_assert_delayed_root_empty(fs_info);
4965	btrfs_destroy_all_delalloc_inodes(fs_info);
4966	btrfs_drop_all_logs(fs_info);
4967	mutex_unlock(&fs_info->transaction_kthread_mutex);
4968
4969	return 0;
4970}
4971
4972int btrfs_init_root_free_objectid(struct btrfs_root *root)
4973{
4974	struct btrfs_path *path;
4975	int ret;
4976	struct extent_buffer *l;
4977	struct btrfs_key search_key;
4978	struct btrfs_key found_key;
4979	int slot;
4980
4981	path = btrfs_alloc_path();
4982	if (!path)
4983		return -ENOMEM;
4984
4985	search_key.objectid = BTRFS_LAST_FREE_OBJECTID;
4986	search_key.type = -1;
4987	search_key.offset = (u64)-1;
4988	ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
4989	if (ret < 0)
4990		goto error;
4991	BUG_ON(ret == 0); /* Corruption */
4992	if (path->slots[0] > 0) {
4993		slot = path->slots[0] - 1;
4994		l = path->nodes[0];
4995		btrfs_item_key_to_cpu(l, &found_key, slot);
4996		root->free_objectid = max_t(u64, found_key.objectid + 1,
4997					    BTRFS_FIRST_FREE_OBJECTID);
4998	} else {
4999		root->free_objectid = BTRFS_FIRST_FREE_OBJECTID;
5000	}
5001	ret = 0;
5002error:
5003	btrfs_free_path(path);
5004	return ret;
5005}
5006
5007int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid)
5008{
5009	int ret;
5010	mutex_lock(&root->objectid_mutex);
5011
5012	if (unlikely(root->free_objectid >= BTRFS_LAST_FREE_OBJECTID)) {
5013		btrfs_warn(root->fs_info,
5014			   "the objectid of root %llu reaches its highest value",
5015			   root->root_key.objectid);
5016		ret = -ENOSPC;
5017		goto out;
5018	}
5019
5020	*objectid = root->free_objectid++;
5021	ret = 0;
5022out:
5023	mutex_unlock(&root->objectid_mutex);
5024	return ret;
5025}