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v6.9.4
   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 "dev-replace.h"
  33#include "raid56.h"
  34#include "sysfs.h"
  35#include "qgroup.h"
  36#include "compression.h"
  37#include "tree-checker.h"
  38#include "ref-verify.h"
  39#include "block-group.h"
  40#include "discard.h"
  41#include "space-info.h"
  42#include "zoned.h"
  43#include "subpage.h"
  44#include "fs.h"
  45#include "accessors.h"
  46#include "extent-tree.h"
  47#include "root-tree.h"
  48#include "defrag.h"
  49#include "uuid-tree.h"
  50#include "relocation.h"
  51#include "scrub.h"
  52#include "super.h"
  53
  54#define BTRFS_SUPER_FLAG_SUPP	(BTRFS_HEADER_FLAG_WRITTEN |\
  55				 BTRFS_HEADER_FLAG_RELOC |\
  56				 BTRFS_SUPER_FLAG_ERROR |\
  57				 BTRFS_SUPER_FLAG_SEEDING |\
  58				 BTRFS_SUPER_FLAG_METADUMP |\
  59				 BTRFS_SUPER_FLAG_METADUMP_V2)
  60
  61static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info);
  62static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info);
  63
  64static void btrfs_free_csum_hash(struct btrfs_fs_info *fs_info)
  65{
  66	if (fs_info->csum_shash)
  67		crypto_free_shash(fs_info->csum_shash);
  68}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  69
  70/*
  71 * Compute the csum of a btree block and store the result to provided buffer.
 
 
  72 */
  73static void csum_tree_block(struct extent_buffer *buf, u8 *result)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  74{
  75	struct btrfs_fs_info *fs_info = buf->fs_info;
  76	int num_pages;
  77	u32 first_page_part;
  78	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
  79	char *kaddr;
  80	int i;
  81
  82	shash->tfm = fs_info->csum_shash;
  83	crypto_shash_init(shash);
 
  84
  85	if (buf->addr) {
  86		/* Pages are contiguous, handle them as a big one. */
  87		kaddr = buf->addr;
  88		first_page_part = fs_info->nodesize;
  89		num_pages = 1;
  90	} else {
  91		kaddr = folio_address(buf->folios[0]);
  92		first_page_part = min_t(u32, PAGE_SIZE, fs_info->nodesize);
  93		num_pages = num_extent_pages(buf);
  94	}
 
  95
  96	crypto_shash_update(shash, kaddr + BTRFS_CSUM_SIZE,
  97			    first_page_part - BTRFS_CSUM_SIZE);
 
 
  98
  99	/*
 100	 * Multiple single-page folios case would reach here.
 101	 *
 102	 * nodesize <= PAGE_SIZE and large folio all handled by above
 103	 * crypto_shash_update() already.
 104	 */
 105	for (i = 1; i < num_pages && INLINE_EXTENT_BUFFER_PAGES > 1; i++) {
 106		kaddr = folio_address(buf->folios[i]);
 107		crypto_shash_update(shash, kaddr, PAGE_SIZE);
 108	}
 109	memset(result, 0, BTRFS_CSUM_SIZE);
 110	crypto_shash_final(shash, result);
 111}
 112
 
 
 113/*
 114 * we can't consider a given block up to date unless the transid of the
 115 * block matches the transid in the parent node's pointer.  This is how we
 116 * detect blocks that either didn't get written at all or got written
 117 * in the wrong place.
 118 */
 119int btrfs_buffer_uptodate(struct extent_buffer *eb, u64 parent_transid, int atomic)
 120{
 121	if (!extent_buffer_uptodate(eb))
 122		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 123
 124	if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 125		return 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 126
 127	if (atomic)
 128		return -EAGAIN;
 
 
 
 129
 130	if (!extent_buffer_uptodate(eb) ||
 131	    btrfs_header_generation(eb) != parent_transid) {
 132		btrfs_err_rl(eb->fs_info,
 133"parent transid verify failed on logical %llu mirror %u wanted %llu found %llu",
 134			eb->start, eb->read_mirror,
 135			parent_transid, btrfs_header_generation(eb));
 136		clear_extent_buffer_uptodate(eb);
 137		return 0;
 138	}
 139	return 1;
 140}
 141
 142static bool btrfs_supported_super_csum(u16 csum_type)
 143{
 144	switch (csum_type) {
 145	case BTRFS_CSUM_TYPE_CRC32:
 146	case BTRFS_CSUM_TYPE_XXHASH:
 147	case BTRFS_CSUM_TYPE_SHA256:
 148	case BTRFS_CSUM_TYPE_BLAKE2:
 149		return true;
 150	default:
 151		return false;
 152	}
 153}
 154
 155/*
 156 * Return 0 if the superblock checksum type matches the checksum value of that
 157 * algorithm. Pass the raw disk superblock data.
 158 */
 159int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
 160			   const struct btrfs_super_block *disk_sb)
 161{
 162	char result[BTRFS_CSUM_SIZE];
 163	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 164
 165	shash->tfm = fs_info->csum_shash;
 166
 167	/*
 168	 * The super_block structure does not span the whole
 169	 * BTRFS_SUPER_INFO_SIZE range, we expect that the unused space is
 170	 * filled with zeros and is included in the checksum.
 171	 */
 172	crypto_shash_digest(shash, (const u8 *)disk_sb + BTRFS_CSUM_SIZE,
 173			    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE, result);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 174
 175	if (memcmp(disk_sb->csum, result, fs_info->csum_size))
 176		return 1;
 177
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 178	return 0;
 179}
 180
 181static int btrfs_repair_eb_io_failure(const struct extent_buffer *eb,
 182				      int mirror_num)
 
 
 
 
 
 
 183{
 184	struct btrfs_fs_info *fs_info = eb->fs_info;
 185	int num_folios = num_extent_folios(eb);
 186	int ret = 0;
 187
 188	if (sb_rdonly(fs_info->sb))
 189		return -EROFS;
 190
 191	for (int i = 0; i < num_folios; i++) {
 192		struct folio *folio = eb->folios[i];
 193		u64 start = max_t(u64, eb->start, folio_pos(folio));
 194		u64 end = min_t(u64, eb->start + eb->len,
 195				folio_pos(folio) + eb->folio_size);
 196		u32 len = end - start;
 197
 198		ret = btrfs_repair_io_failure(fs_info, 0, start, len,
 199					      start, folio, offset_in_folio(folio, start),
 200					      mirror_num);
 201		if (ret)
 202			break;
 203	}
 204
 
 
 
 
 
 
 
 
 
 205	return ret;
 206}
 207
 208/*
 209 * helper to read a given tree block, doing retries as required when
 210 * the checksums don't match and we have alternate mirrors to try.
 211 *
 212 * @check:		expected tree parentness check, see the comments of the
 213 *			structure for details.
 214 */
 215int btrfs_read_extent_buffer(struct extent_buffer *eb,
 216			     struct btrfs_tree_parent_check *check)
 
 217{
 218	struct btrfs_fs_info *fs_info = eb->fs_info;
 219	int failed = 0;
 220	int ret;
 221	int num_copies = 0;
 222	int mirror_num = 0;
 223	int failed_mirror = 0;
 224
 225	ASSERT(check);
 226
 
 
 227	while (1) {
 228		clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 229		ret = read_extent_buffer_pages(eb, WAIT_COMPLETE, mirror_num, check);
 230		if (!ret)
 231			break;
 
 232
 233		num_copies = btrfs_num_copies(fs_info,
 
 
 
 
 
 
 
 
 234					      eb->start, eb->len);
 235		if (num_copies == 1)
 236			break;
 237
 238		if (!failed_mirror) {
 239			failed = 1;
 240			failed_mirror = eb->read_mirror;
 241		}
 242
 243		mirror_num++;
 244		if (mirror_num == failed_mirror)
 245			mirror_num++;
 246
 247		if (mirror_num > num_copies)
 248			break;
 249	}
 250
 251	if (failed && !ret && failed_mirror)
 252		btrfs_repair_eb_io_failure(eb, failed_mirror);
 253
 254	return ret;
 255}
 256
 257/*
 258 * Checksum a dirty tree block before IO.
 
 259 */
 260blk_status_t btree_csum_one_bio(struct btrfs_bio *bbio)
 
 261{
 262	struct extent_buffer *eb = bbio->private;
 263	struct btrfs_fs_info *fs_info = eb->fs_info;
 264	u64 found_start = btrfs_header_bytenr(eb);
 265	u64 last_trans;
 266	u8 result[BTRFS_CSUM_SIZE];
 267	int ret;
 268
 269	/* Btree blocks are always contiguous on disk. */
 270	if (WARN_ON_ONCE(bbio->file_offset != eb->start))
 271		return BLK_STS_IOERR;
 272	if (WARN_ON_ONCE(bbio->bio.bi_iter.bi_size != eb->len))
 273		return BLK_STS_IOERR;
 274
 275	/*
 276	 * If an extent_buffer is marked as EXTENT_BUFFER_ZONED_ZEROOUT, don't
 277	 * checksum it but zero-out its content. This is done to preserve
 278	 * ordering of I/O without unnecessarily writing out data.
 279	 */
 280	if (test_bit(EXTENT_BUFFER_ZONED_ZEROOUT, &eb->bflags)) {
 281		memzero_extent_buffer(eb, 0, eb->len);
 282		return BLK_STS_OK;
 283	}
 284
 285	if (WARN_ON_ONCE(found_start != eb->start))
 286		return BLK_STS_IOERR;
 287	if (WARN_ON(!btrfs_folio_test_uptodate(fs_info, eb->folios[0],
 288					       eb->start, eb->len)))
 289		return BLK_STS_IOERR;
 290
 291	ASSERT(memcmp_extent_buffer(eb, fs_info->fs_devices->metadata_uuid,
 292				    offsetof(struct btrfs_header, fsid),
 293				    BTRFS_FSID_SIZE) == 0);
 294	csum_tree_block(eb, result);
 295
 296	if (btrfs_header_level(eb))
 297		ret = btrfs_check_node(eb);
 298	else
 299		ret = btrfs_check_leaf(eb);
 300
 301	if (ret < 0)
 302		goto error;
 
 
 
 
 
 
 
 303
 304	/*
 305	 * Also check the generation, the eb reached here must be newer than
 306	 * last committed. Or something seriously wrong happened.
 307	 */
 308	last_trans = btrfs_get_last_trans_committed(fs_info);
 309	if (unlikely(btrfs_header_generation(eb) <= last_trans)) {
 310		ret = -EUCLEAN;
 311		btrfs_err(fs_info,
 312			"block=%llu bad generation, have %llu expect > %llu",
 313			  eb->start, btrfs_header_generation(eb), last_trans);
 314		goto error;
 315	}
 316	write_extent_buffer(eb, result, 0, fs_info->csum_size);
 317	return BLK_STS_OK;
 318
 319error:
 320	btrfs_print_tree(eb, 0);
 321	btrfs_err(fs_info, "block=%llu write time tree block corruption detected",
 322		  eb->start);
 323	/*
 324	 * Be noisy if this is an extent buffer from a log tree. We don't abort
 325	 * a transaction in case there's a bad log tree extent buffer, we just
 326	 * fallback to a transaction commit. Still we want to know when there is
 327	 * a bad log tree extent buffer, as that may signal a bug somewhere.
 328	 */
 329	WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG) ||
 330		btrfs_header_owner(eb) == BTRFS_TREE_LOG_OBJECTID);
 331	return errno_to_blk_status(ret);
 332}
 333
 334static bool check_tree_block_fsid(struct extent_buffer *eb)
 
 335{
 336	struct btrfs_fs_info *fs_info = eb->fs_info;
 337	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
 338	u8 fsid[BTRFS_FSID_SIZE];
 339
 340	read_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid),
 341			   BTRFS_FSID_SIZE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 342
 343	/*
 344	 * alloc_fsid_devices() copies the fsid into fs_devices::metadata_uuid.
 345	 * This is then overwritten by metadata_uuid if it is present in the
 346	 * device_list_add(). The same true for a seed device as well. So use of
 347	 * fs_devices::metadata_uuid is appropriate here.
 348	 */
 349	if (memcmp(fsid, fs_info->fs_devices->metadata_uuid, BTRFS_FSID_SIZE) == 0)
 350		return false;
 
 
 
 
 
 
 
 
 351
 352	list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list)
 353		if (!memcmp(fsid, seed_devs->fsid, BTRFS_FSID_SIZE))
 354			return false;
 
 
 
 
 
 
 
 355
 356	return true;
 
 
 
 
 
 
 
 
 
 
 
 
 357}
 358
 359/* Do basic extent buffer checks at read time */
 360int btrfs_validate_extent_buffer(struct extent_buffer *eb,
 361				 struct btrfs_tree_parent_check *check)
 362{
 363	struct btrfs_fs_info *fs_info = eb->fs_info;
 364	u64 found_start;
 365	const u32 csum_size = fs_info->csum_size;
 366	u8 found_level;
 367	u8 result[BTRFS_CSUM_SIZE];
 368	const u8 *header_csum;
 369	int ret = 0;
 370
 371	ASSERT(check);
 372
 373	found_start = btrfs_header_bytenr(eb);
 374	if (found_start != eb->start) {
 375		btrfs_err_rl(fs_info,
 376			"bad tree block start, mirror %u want %llu have %llu",
 377			     eb->read_mirror, eb->start, found_start);
 378		ret = -EIO;
 379		goto out;
 380	}
 381	if (check_tree_block_fsid(eb)) {
 382		btrfs_err_rl(fs_info, "bad fsid on logical %llu mirror %u",
 383			     eb->start, eb->read_mirror);
 384		ret = -EIO;
 385		goto out;
 386	}
 387	found_level = btrfs_header_level(eb);
 388	if (found_level >= BTRFS_MAX_LEVEL) {
 389		btrfs_err(fs_info,
 390			"bad tree block level, mirror %u level %d on logical %llu",
 391			eb->read_mirror, btrfs_header_level(eb), eb->start);
 392		ret = -EIO;
 393		goto out;
 394	}
 395
 396	csum_tree_block(eb, result);
 397	header_csum = folio_address(eb->folios[0]) +
 398		get_eb_offset_in_folio(eb, offsetof(struct btrfs_header, csum));
 399
 400	if (memcmp(result, header_csum, csum_size) != 0) {
 401		btrfs_warn_rl(fs_info,
 402"checksum verify failed on logical %llu mirror %u wanted " CSUM_FMT " found " CSUM_FMT " level %d",
 403			      eb->start, eb->read_mirror,
 404			      CSUM_FMT_VALUE(csum_size, header_csum),
 405			      CSUM_FMT_VALUE(csum_size, result),
 406			      btrfs_header_level(eb));
 407		ret = -EUCLEAN;
 408		goto out;
 409	}
 410
 411	if (found_level != check->level) {
 412		btrfs_err(fs_info,
 413		"level verify failed on logical %llu mirror %u wanted %u found %u",
 414			  eb->start, eb->read_mirror, check->level, found_level);
 415		ret = -EIO;
 416		goto out;
 417	}
 418	if (unlikely(check->transid &&
 419		     btrfs_header_generation(eb) != check->transid)) {
 420		btrfs_err_rl(eb->fs_info,
 421"parent transid verify failed on logical %llu mirror %u wanted %llu found %llu",
 422				eb->start, eb->read_mirror, check->transid,
 423				btrfs_header_generation(eb));
 424		ret = -EIO;
 425		goto out;
 426	}
 427	if (check->has_first_key) {
 428		struct btrfs_key *expect_key = &check->first_key;
 429		struct btrfs_key found_key;
 430
 431		if (found_level)
 432			btrfs_node_key_to_cpu(eb, &found_key, 0);
 433		else
 434			btrfs_item_key_to_cpu(eb, &found_key, 0);
 435		if (unlikely(btrfs_comp_cpu_keys(expect_key, &found_key))) {
 436			btrfs_err(fs_info,
 437"tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
 438				  eb->start, check->transid,
 439				  expect_key->objectid,
 440				  expect_key->type, expect_key->offset,
 441				  found_key.objectid, found_key.type,
 442				  found_key.offset);
 443			ret = -EUCLEAN;
 444			goto out;
 445		}
 446	}
 447	if (check->owner_root) {
 448		ret = btrfs_check_eb_owner(eb, check->owner_root);
 449		if (ret < 0)
 450			goto out;
 451	}
 452
 453	/*
 454	 * If this is a leaf block and it is corrupt, set the corrupt bit so
 455	 * that we don't try and read the other copies of this block, just
 456	 * return -EIO.
 457	 */
 458	if (found_level == 0 && btrfs_check_leaf(eb)) {
 459		set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 460		ret = -EIO;
 461	}
 462
 463	if (found_level > 0 && btrfs_check_node(eb))
 464		ret = -EIO;
 465
 466	if (ret)
 467		btrfs_err(fs_info,
 468		"read time tree block corruption detected on logical %llu mirror %u",
 469			  eb->start, eb->read_mirror);
 470out:
 471	return ret;
 472}
 473
 474#ifdef CONFIG_MIGRATION
 475static int btree_migrate_folio(struct address_space *mapping,
 476		struct folio *dst, struct folio *src, enum migrate_mode mode)
 477{
 478	/*
 479	 * we can't safely write a btree page from here,
 480	 * we haven't done the locking hook
 481	 */
 482	if (folio_test_dirty(src))
 483		return -EAGAIN;
 484	/*
 485	 * Buffers may be managed in a filesystem specific way.
 486	 * We must have no buffers or drop them.
 487	 */
 488	if (folio_get_private(src) &&
 489	    !filemap_release_folio(src, GFP_KERNEL))
 490		return -EAGAIN;
 491	return migrate_folio(mapping, dst, src, mode);
 
 
 
 
 
 
 
 
 
 
 
 
 492}
 493#else
 494#define btree_migrate_folio NULL
 495#endif
 496
 497static int btree_writepages(struct address_space *mapping,
 498			    struct writeback_control *wbc)
 
 
 
 
 
 
 
 499{
 500	int ret;
 
 
 
 501
 502	if (wbc->sync_mode == WB_SYNC_NONE) {
 503		struct btrfs_fs_info *fs_info;
 
 
 
 
 504
 505		if (wbc->for_kupdate)
 506			return 0;
 
 
 507
 508		fs_info = inode_to_fs_info(mapping->host);
 509		/* this is a bit racy, but that's ok */
 510		ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
 511					     BTRFS_DIRTY_METADATA_THRESH,
 512					     fs_info->dirty_metadata_batch);
 513		if (ret < 0)
 514			return 0;
 515	}
 516	return btree_write_cache_pages(mapping, wbc);
 517}
 518
 519static bool btree_release_folio(struct folio *folio, gfp_t gfp_flags)
 520{
 521	if (folio_test_writeback(folio) || folio_test_dirty(folio))
 522		return false;
 523
 524	return try_release_extent_buffer(&folio->page);
 
 
 
 525}
 526
 527static void btree_invalidate_folio(struct folio *folio, size_t offset,
 528				 size_t length)
 529{
 530	struct extent_io_tree *tree;
 
 
 531
 532	tree = &folio_to_inode(folio)->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(folio_to_fs_info(folio),
 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 = inode_to_fs_info(mapping->host);
 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		WARN_ON_ONCE(1);
1248		while (refcount_read(&root->refs) > 1)
1249			btrfs_put_root(root);
1250		btrfs_put_root(root);
1251	}
1252#endif
1253}
1254
1255static void free_global_roots(struct btrfs_fs_info *fs_info)
1256{
1257	struct btrfs_root *root;
1258	struct rb_node *node;
1259
1260	while ((node = rb_first_postorder(&fs_info->global_root_tree)) != NULL) {
1261		root = rb_entry(node, struct btrfs_root, rb_node);
1262		rb_erase(&root->rb_node, &fs_info->global_root_tree);
1263		btrfs_put_root(root);
1264	}
1265}
1266
1267void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
1268{
1269	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
1270	percpu_counter_destroy(&fs_info->delalloc_bytes);
1271	percpu_counter_destroy(&fs_info->ordered_bytes);
1272	percpu_counter_destroy(&fs_info->dev_replace.bio_counter);
1273	btrfs_free_csum_hash(fs_info);
1274	btrfs_free_stripe_hash_table(fs_info);
1275	btrfs_free_ref_cache(fs_info);
1276	kfree(fs_info->balance_ctl);
1277	kfree(fs_info->delayed_root);
1278	free_global_roots(fs_info);
1279	btrfs_put_root(fs_info->tree_root);
1280	btrfs_put_root(fs_info->chunk_root);
1281	btrfs_put_root(fs_info->dev_root);
1282	btrfs_put_root(fs_info->quota_root);
1283	btrfs_put_root(fs_info->uuid_root);
1284	btrfs_put_root(fs_info->fs_root);
1285	btrfs_put_root(fs_info->data_reloc_root);
1286	btrfs_put_root(fs_info->block_group_root);
1287	btrfs_put_root(fs_info->stripe_root);
1288	btrfs_check_leaked_roots(fs_info);
1289	btrfs_extent_buffer_leak_debug_check(fs_info);
1290	kfree(fs_info->super_copy);
1291	kfree(fs_info->super_for_commit);
1292	kfree(fs_info->subpage_info);
1293	kvfree(fs_info);
1294}
1295
1296
1297/*
1298 * Get an in-memory reference of a root structure.
1299 *
1300 * For essential trees like root/extent tree, we grab it from fs_info directly.
1301 * For subvolume trees, we check the cached filesystem roots first. If not
1302 * found, then read it from disk and add it to cached fs roots.
1303 *
1304 * Caller should release the root by calling btrfs_put_root() after the usage.
1305 *
1306 * NOTE: Reloc and log trees can't be read by this function as they share the
1307 *	 same root objectid.
1308 *
1309 * @objectid:	root id
1310 * @anon_dev:	preallocated anonymous block device number for new roots,
1311 *		pass NULL for a new allocation.
1312 * @check_ref:	whether to check root item references, If true, return -ENOENT
1313 *		for orphan roots
1314 */
1315static struct btrfs_root *btrfs_get_root_ref(struct btrfs_fs_info *fs_info,
1316					     u64 objectid, dev_t *anon_dev,
1317					     bool check_ref)
1318{
1319	struct btrfs_root *root;
1320	struct btrfs_path *path;
1321	struct btrfs_key key;
1322	int ret;
1323
1324	root = btrfs_get_global_root(fs_info, objectid);
1325	if (root)
1326		return root;
1327
1328	/*
1329	 * If we're called for non-subvolume trees, and above function didn't
1330	 * find one, do not try to read it from disk.
1331	 *
1332	 * This is namely for free-space-tree and quota tree, which can change
1333	 * at runtime and should only be grabbed from fs_info.
1334	 */
1335	if (!is_fstree(objectid) && objectid != BTRFS_DATA_RELOC_TREE_OBJECTID)
1336		return ERR_PTR(-ENOENT);
1337again:
1338	root = btrfs_lookup_fs_root(fs_info, objectid);
1339	if (root) {
1340		/*
1341		 * Some other caller may have read out the newly inserted
1342		 * subvolume already (for things like backref walk etc).  Not
1343		 * that common but still possible.  In that case, we just need
1344		 * to free the anon_dev.
1345		 */
1346		if (unlikely(anon_dev && *anon_dev)) {
1347			free_anon_bdev(*anon_dev);
1348			*anon_dev = 0;
1349		}
1350
1351		if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1352			btrfs_put_root(root);
1353			return ERR_PTR(-ENOENT);
1354		}
1355		return root;
1356	}
1357
1358	key.objectid = objectid;
1359	key.type = BTRFS_ROOT_ITEM_KEY;
1360	key.offset = (u64)-1;
1361	root = btrfs_read_tree_root(fs_info->tree_root, &key);
1362	if (IS_ERR(root))
1363		return root;
1364
1365	if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1366		ret = -ENOENT;
 
 
 
1367		goto fail;
1368	}
1369
1370	ret = btrfs_init_fs_root(root, anon_dev ? *anon_dev : 0);
 
 
 
 
 
1371	if (ret)
1372		goto fail;
1373
1374	path = btrfs_alloc_path();
1375	if (!path) {
1376		ret = -ENOMEM;
1377		goto fail;
1378	}
1379	key.objectid = BTRFS_ORPHAN_OBJECTID;
1380	key.type = BTRFS_ORPHAN_ITEM_KEY;
1381	key.offset = objectid;
1382
1383	ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
1384	btrfs_free_path(path);
1385	if (ret < 0)
1386		goto fail;
1387	if (ret == 0)
1388		set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state);
 
 
 
 
 
 
 
 
 
 
 
1389
1390	ret = btrfs_insert_fs_root(fs_info, root);
 
1391	if (ret) {
1392		if (ret == -EEXIST) {
1393			btrfs_put_root(root);
1394			goto again;
1395		}
1396		goto fail;
1397	}
 
 
 
 
1398	return root;
1399fail:
1400	/*
1401	 * If our caller provided us an anonymous device, then it's his
1402	 * responsibility to free it in case we fail. So we have to set our
1403	 * root's anon_dev to 0 to avoid a double free, once by btrfs_put_root()
1404	 * and once again by our caller.
1405	 */
1406	if (anon_dev && *anon_dev)
1407		root->anon_dev = 0;
1408	btrfs_put_root(root);
1409	return ERR_PTR(ret);
1410}
1411
1412/*
1413 * Get in-memory reference of a root structure
1414 *
1415 * @objectid:	tree objectid
1416 * @check_ref:	if set, verify that the tree exists and the item has at least
1417 *		one reference
1418 */
1419struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
1420				     u64 objectid, bool check_ref)
1421{
1422	return btrfs_get_root_ref(fs_info, objectid, NULL, check_ref);
1423}
 
 
1424
1425/*
1426 * Get in-memory reference of a root structure, created as new, optionally pass
1427 * the anonymous block device id
1428 *
1429 * @objectid:	tree objectid
1430 * @anon_dev:	if NULL, allocate a new anonymous block device or use the
1431 *		parameter value if not NULL
1432 */
1433struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
1434					 u64 objectid, dev_t *anon_dev)
1435{
1436	return btrfs_get_root_ref(fs_info, objectid, anon_dev, true);
1437}
1438
1439/*
1440 * Return a root for the given objectid.
1441 *
1442 * @fs_info:	the fs_info
1443 * @objectid:	the objectid we need to lookup
1444 *
1445 * This is exclusively used for backref walking, and exists specifically because
1446 * of how qgroups does lookups.  Qgroups will do a backref lookup at delayed ref
1447 * creation time, which means we may have to read the tree_root in order to look
1448 * up a fs root that is not in memory.  If the root is not in memory we will
1449 * read the tree root commit root and look up the fs root from there.  This is a
1450 * temporary root, it will not be inserted into the radix tree as it doesn't
1451 * have the most uptodate information, it'll simply be discarded once the
1452 * backref code is finished using the root.
1453 */
1454struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
1455						 struct btrfs_path *path,
1456						 u64 objectid)
1457{
1458	struct btrfs_root *root;
1459	struct btrfs_key key;
1460
1461	ASSERT(path->search_commit_root && path->skip_locking);
1462
1463	/*
1464	 * This can return -ENOENT if we ask for a root that doesn't exist, but
1465	 * since this is called via the backref walking code we won't be looking
1466	 * up a root that doesn't exist, unless there's corruption.  So if root
1467	 * != NULL just return it.
1468	 */
1469	root = btrfs_get_global_root(fs_info, objectid);
1470	if (root)
1471		return root;
1472
1473	root = btrfs_lookup_fs_root(fs_info, objectid);
1474	if (root)
1475		return root;
1476
1477	key.objectid = objectid;
1478	key.type = BTRFS_ROOT_ITEM_KEY;
1479	key.offset = (u64)-1;
1480	root = read_tree_root_path(fs_info->tree_root, path, &key);
1481	btrfs_release_path(path);
1482
1483	return root;
1484}
1485
1486static int cleaner_kthread(void *arg)
1487{
1488	struct btrfs_fs_info *fs_info = arg;
1489	int again;
1490
1491	while (1) {
1492		again = 0;
1493
1494		set_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1495
1496		/* Make the cleaner go to sleep early. */
1497		if (btrfs_need_cleaner_sleep(fs_info))
1498			goto sleep;
1499
1500		/*
1501		 * Do not do anything if we might cause open_ctree() to block
1502		 * before we have finished mounting the filesystem.
1503		 */
1504		if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags))
1505			goto sleep;
1506
1507		if (!mutex_trylock(&fs_info->cleaner_mutex))
1508			goto sleep;
1509
1510		/*
1511		 * Avoid the problem that we change the status of the fs
1512		 * during the above check and trylock.
1513		 */
1514		if (btrfs_need_cleaner_sleep(fs_info)) {
1515			mutex_unlock(&fs_info->cleaner_mutex);
1516			goto sleep;
1517		}
 
 
 
 
 
 
 
 
 
 
 
 
1518
1519		if (test_and_clear_bit(BTRFS_FS_FEATURE_CHANGED, &fs_info->flags))
1520			btrfs_sysfs_feature_update(fs_info);
 
 
1521
1522		btrfs_run_delayed_iputs(fs_info);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1523
1524		again = btrfs_clean_one_deleted_snapshot(fs_info);
1525		mutex_unlock(&fs_info->cleaner_mutex);
 
1526
1527		/*
1528		 * The defragger has dealt with the R/O remount and umount,
1529		 * needn't do anything special here.
1530		 */
1531		btrfs_run_defrag_inodes(fs_info);
1532
1533		/*
1534		 * Acquires fs_info->reclaim_bgs_lock to avoid racing
1535		 * with relocation (btrfs_relocate_chunk) and relocation
1536		 * acquires fs_info->cleaner_mutex (btrfs_relocate_block_group)
1537		 * after acquiring fs_info->reclaim_bgs_lock. So we
1538		 * can't hold, nor need to, fs_info->cleaner_mutex when deleting
1539		 * unused block groups.
1540		 */
1541		btrfs_delete_unused_bgs(fs_info);
1542
1543		/*
1544		 * Reclaim block groups in the reclaim_bgs list after we deleted
1545		 * all unused block_groups. This possibly gives us some more free
1546		 * space.
1547		 */
1548		btrfs_reclaim_bgs(fs_info);
1549sleep:
1550		clear_and_wake_up_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1551		if (kthread_should_park())
1552			kthread_parkme();
1553		if (kthread_should_stop())
1554			return 0;
1555		if (!again) {
1556			set_current_state(TASK_INTERRUPTIBLE);
1557			schedule();
 
1558			__set_current_state(TASK_RUNNING);
1559		}
1560	}
 
1561}
1562
1563static int transaction_kthread(void *arg)
1564{
1565	struct btrfs_root *root = arg;
1566	struct btrfs_fs_info *fs_info = root->fs_info;
1567	struct btrfs_trans_handle *trans;
1568	struct btrfs_transaction *cur;
1569	u64 transid;
1570	time64_t delta;
1571	unsigned long delay;
1572	bool cannot_commit;
1573
1574	do {
1575		cannot_commit = false;
1576		delay = msecs_to_jiffies(fs_info->commit_interval * 1000);
1577		mutex_lock(&fs_info->transaction_kthread_mutex);
1578
1579		spin_lock(&fs_info->trans_lock);
1580		cur = fs_info->running_transaction;
1581		if (!cur) {
1582			spin_unlock(&fs_info->trans_lock);
1583			goto sleep;
1584		}
1585
1586		delta = ktime_get_seconds() - cur->start_time;
1587		if (!test_and_clear_bit(BTRFS_FS_COMMIT_TRANS, &fs_info->flags) &&
1588		    cur->state < TRANS_STATE_COMMIT_PREP &&
1589		    delta < fs_info->commit_interval) {
1590			spin_unlock(&fs_info->trans_lock);
1591			delay -= msecs_to_jiffies((delta - 1) * 1000);
1592			delay = min(delay,
1593				    msecs_to_jiffies(fs_info->commit_interval * 1000));
1594			goto sleep;
1595		}
1596		transid = cur->transid;
1597		spin_unlock(&fs_info->trans_lock);
1598
1599		/* If the file system is aborted, this will always fail. */
1600		trans = btrfs_attach_transaction(root);
1601		if (IS_ERR(trans)) {
1602			if (PTR_ERR(trans) != -ENOENT)
1603				cannot_commit = true;
1604			goto sleep;
1605		}
1606		if (transid == trans->transid) {
1607			btrfs_commit_transaction(trans);
 
1608		} else {
1609			btrfs_end_transaction(trans);
1610		}
1611sleep:
1612		wake_up_process(fs_info->cleaner_kthread);
1613		mutex_unlock(&fs_info->transaction_kthread_mutex);
1614
1615		if (BTRFS_FS_ERROR(fs_info))
1616			btrfs_cleanup_transaction(fs_info);
1617		if (!kthread_should_stop() &&
1618				(!btrfs_transaction_blocked(fs_info) ||
1619				 cannot_commit))
1620			schedule_timeout_interruptible(delay);
 
 
 
1621	} while (!kthread_should_stop());
1622	return 0;
1623}
1624
1625/*
1626 * This will find the highest generation in the array of root backups.  The
1627 * index of the highest array is returned, or -EINVAL if we can't find
1628 * anything.
1629 *
1630 * We check to make sure the array is valid by comparing the
1631 * generation of the latest  root in the array with the generation
1632 * in the super block.  If they don't match we pitch it.
1633 */
1634static int find_newest_super_backup(struct btrfs_fs_info *info)
1635{
1636	const u64 newest_gen = btrfs_super_generation(info->super_copy);
1637	u64 cur;
1638	struct btrfs_root_backup *root_backup;
1639	int i;
1640
1641	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
1642		root_backup = info->super_copy->super_roots + i;
1643		cur = btrfs_backup_tree_root_gen(root_backup);
1644		if (cur == newest_gen)
1645			return i;
1646	}
1647
1648	return -EINVAL;
1649}
1650
1651/*
1652 * copy all the root pointers into the super backup array.
1653 * this will bump the backup pointer by one when it is
1654 * done
1655 */
1656static void backup_super_roots(struct btrfs_fs_info *info)
1657{
1658	const int next_backup = info->backup_root_index;
1659	struct btrfs_root_backup *root_backup;
1660
1661	root_backup = info->super_for_commit->super_roots + next_backup;
1662
1663	/*
1664	 * make sure all of our padding and empty slots get zero filled
1665	 * regardless of which ones we use today
1666	 */
1667	memset(root_backup, 0, sizeof(*root_backup));
1668
1669	info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
1670
1671	btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
1672	btrfs_set_backup_tree_root_gen(root_backup,
1673			       btrfs_header_generation(info->tree_root->node));
1674
1675	btrfs_set_backup_tree_root_level(root_backup,
1676			       btrfs_header_level(info->tree_root->node));
1677
1678	btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
1679	btrfs_set_backup_chunk_root_gen(root_backup,
1680			       btrfs_header_generation(info->chunk_root->node));
1681	btrfs_set_backup_chunk_root_level(root_backup,
1682			       btrfs_header_level(info->chunk_root->node));
1683
1684	if (!btrfs_fs_compat_ro(info, BLOCK_GROUP_TREE)) {
1685		struct btrfs_root *extent_root = btrfs_extent_root(info, 0);
1686		struct btrfs_root *csum_root = btrfs_csum_root(info, 0);
1687
1688		btrfs_set_backup_extent_root(root_backup,
1689					     extent_root->node->start);
1690		btrfs_set_backup_extent_root_gen(root_backup,
1691				btrfs_header_generation(extent_root->node));
1692		btrfs_set_backup_extent_root_level(root_backup,
1693					btrfs_header_level(extent_root->node));
1694
1695		btrfs_set_backup_csum_root(root_backup, csum_root->node->start);
1696		btrfs_set_backup_csum_root_gen(root_backup,
1697					       btrfs_header_generation(csum_root->node));
1698		btrfs_set_backup_csum_root_level(root_backup,
1699						 btrfs_header_level(csum_root->node));
1700	}
1701
1702	/*
1703	 * we might commit during log recovery, which happens before we set
1704	 * the fs_root.  Make sure it is valid before we fill it in.
1705	 */
1706	if (info->fs_root && info->fs_root->node) {
1707		btrfs_set_backup_fs_root(root_backup,
1708					 info->fs_root->node->start);
1709		btrfs_set_backup_fs_root_gen(root_backup,
1710			       btrfs_header_generation(info->fs_root->node));
1711		btrfs_set_backup_fs_root_level(root_backup,
1712			       btrfs_header_level(info->fs_root->node));
1713	}
1714
1715	btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
1716	btrfs_set_backup_dev_root_gen(root_backup,
1717			       btrfs_header_generation(info->dev_root->node));
1718	btrfs_set_backup_dev_root_level(root_backup,
1719				       btrfs_header_level(info->dev_root->node));
1720
1721	btrfs_set_backup_total_bytes(root_backup,
1722			     btrfs_super_total_bytes(info->super_copy));
1723	btrfs_set_backup_bytes_used(root_backup,
1724			     btrfs_super_bytes_used(info->super_copy));
1725	btrfs_set_backup_num_devices(root_backup,
1726			     btrfs_super_num_devices(info->super_copy));
1727
1728	/*
1729	 * if we don't copy this out to the super_copy, it won't get remembered
1730	 * for the next commit
1731	 */
1732	memcpy(&info->super_copy->super_roots,
1733	       &info->super_for_commit->super_roots,
1734	       sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
1735}
1736
1737/*
1738 * Reads a backup root based on the passed priority. Prio 0 is the newest, prio
1739 * 1/2/3 are 2nd newest/3rd newest/4th (oldest) backup roots
1740 *
1741 * @fs_info:  filesystem whose backup roots need to be read
1742 * @priority: priority of backup root required
1743 *
1744 * Returns backup root index on success and -EINVAL otherwise.
1745 */
1746static int read_backup_root(struct btrfs_fs_info *fs_info, u8 priority)
1747{
1748	int backup_index = find_newest_super_backup(fs_info);
1749	struct btrfs_super_block *super = fs_info->super_copy;
1750	struct btrfs_root_backup *root_backup;
1751
1752	if (priority < BTRFS_NUM_BACKUP_ROOTS && backup_index >= 0) {
1753		if (priority == 0)
1754			return backup_index;
1755
1756		backup_index = backup_index + BTRFS_NUM_BACKUP_ROOTS - priority;
1757		backup_index %= BTRFS_NUM_BACKUP_ROOTS;
1758	} else {
1759		return -EINVAL;
1760	}
1761
1762	root_backup = super->super_roots + backup_index;
1763
1764	btrfs_set_super_generation(super,
1765				   btrfs_backup_tree_root_gen(root_backup));
1766	btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
1767	btrfs_set_super_root_level(super,
1768				   btrfs_backup_tree_root_level(root_backup));
1769	btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
1770
1771	/*
1772	 * Fixme: the total bytes and num_devices need to match or we should
1773	 * need a fsck
1774	 */
1775	btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
1776	btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
1777
1778	return backup_index;
1779}
1780
1781/* helper to cleanup workers */
1782static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
1783{
1784	btrfs_destroy_workqueue(fs_info->fixup_workers);
1785	btrfs_destroy_workqueue(fs_info->delalloc_workers);
1786	btrfs_destroy_workqueue(fs_info->workers);
1787	if (fs_info->endio_workers)
1788		destroy_workqueue(fs_info->endio_workers);
1789	if (fs_info->rmw_workers)
1790		destroy_workqueue(fs_info->rmw_workers);
1791	if (fs_info->compressed_write_workers)
1792		destroy_workqueue(fs_info->compressed_write_workers);
1793	btrfs_destroy_workqueue(fs_info->endio_write_workers);
1794	btrfs_destroy_workqueue(fs_info->endio_freespace_worker);
1795	btrfs_destroy_workqueue(fs_info->delayed_workers);
1796	btrfs_destroy_workqueue(fs_info->caching_workers);
1797	btrfs_destroy_workqueue(fs_info->flush_workers);
1798	btrfs_destroy_workqueue(fs_info->qgroup_rescan_workers);
1799	if (fs_info->discard_ctl.discard_workers)
1800		destroy_workqueue(fs_info->discard_ctl.discard_workers);
1801	/*
1802	 * Now that all other work queues are destroyed, we can safely destroy
1803	 * the queues used for metadata I/O, since tasks from those other work
1804	 * queues can do metadata I/O operations.
1805	 */
1806	if (fs_info->endio_meta_workers)
1807		destroy_workqueue(fs_info->endio_meta_workers);
1808}
1809
1810static void free_root_extent_buffers(struct btrfs_root *root)
1811{
1812	if (root) {
1813		free_extent_buffer(root->node);
1814		free_extent_buffer(root->commit_root);
1815		root->node = NULL;
1816		root->commit_root = NULL;
1817	}
1818}
1819
1820static void free_global_root_pointers(struct btrfs_fs_info *fs_info)
1821{
1822	struct btrfs_root *root, *tmp;
1823
1824	rbtree_postorder_for_each_entry_safe(root, tmp,
1825					     &fs_info->global_root_tree,
1826					     rb_node)
1827		free_root_extent_buffers(root);
1828}
1829
1830/* helper to cleanup tree roots */
1831static void free_root_pointers(struct btrfs_fs_info *info, bool free_chunk_root)
1832{
1833	free_root_extent_buffers(info->tree_root);
1834
1835	free_global_root_pointers(info);
1836	free_root_extent_buffers(info->dev_root);
1837	free_root_extent_buffers(info->quota_root);
1838	free_root_extent_buffers(info->uuid_root);
1839	free_root_extent_buffers(info->fs_root);
1840	free_root_extent_buffers(info->data_reloc_root);
1841	free_root_extent_buffers(info->block_group_root);
1842	free_root_extent_buffers(info->stripe_root);
1843	if (free_chunk_root)
1844		free_root_extent_buffers(info->chunk_root);
1845}
1846
1847void btrfs_put_root(struct btrfs_root *root)
1848{
1849	if (!root)
1850		return;
1851
1852	if (refcount_dec_and_test(&root->refs)) {
1853		WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
1854		WARN_ON(test_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state));
1855		if (root->anon_dev)
1856			free_anon_bdev(root->anon_dev);
1857		free_root_extent_buffers(root);
1858#ifdef CONFIG_BTRFS_DEBUG
1859		spin_lock(&root->fs_info->fs_roots_radix_lock);
1860		list_del_init(&root->leak_list);
1861		spin_unlock(&root->fs_info->fs_roots_radix_lock);
1862#endif
1863		kfree(root);
1864	}
1865}
1866
1867void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info)
1868{
1869	int ret;
1870	struct btrfs_root *gang[8];
1871	int i;
1872
1873	while (!list_empty(&fs_info->dead_roots)) {
1874		gang[0] = list_entry(fs_info->dead_roots.next,
1875				     struct btrfs_root, root_list);
1876		list_del(&gang[0]->root_list);
1877
1878		if (test_bit(BTRFS_ROOT_IN_RADIX, &gang[0]->state))
1879			btrfs_drop_and_free_fs_root(fs_info, gang[0]);
1880		btrfs_put_root(gang[0]);
1881	}
1882
1883	while (1) {
1884		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
1885					     (void **)gang, 0,
1886					     ARRAY_SIZE(gang));
1887		if (!ret)
1888			break;
1889		for (i = 0; i < ret; i++)
1890			btrfs_drop_and_free_fs_root(fs_info, gang[i]);
1891	}
1892}
1893
1894static void btrfs_init_scrub(struct btrfs_fs_info *fs_info)
1895{
1896	mutex_init(&fs_info->scrub_lock);
1897	atomic_set(&fs_info->scrubs_running, 0);
1898	atomic_set(&fs_info->scrub_pause_req, 0);
1899	atomic_set(&fs_info->scrubs_paused, 0);
1900	atomic_set(&fs_info->scrub_cancel_req, 0);
1901	init_waitqueue_head(&fs_info->scrub_pause_wait);
1902	refcount_set(&fs_info->scrub_workers_refcnt, 0);
1903}
1904
1905static void btrfs_init_balance(struct btrfs_fs_info *fs_info)
1906{
1907	spin_lock_init(&fs_info->balance_lock);
1908	mutex_init(&fs_info->balance_mutex);
1909	atomic_set(&fs_info->balance_pause_req, 0);
1910	atomic_set(&fs_info->balance_cancel_req, 0);
1911	fs_info->balance_ctl = NULL;
1912	init_waitqueue_head(&fs_info->balance_wait_q);
1913	atomic_set(&fs_info->reloc_cancel_req, 0);
1914}
1915
1916static int btrfs_init_btree_inode(struct super_block *sb)
1917{
1918	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
1919	unsigned long hash = btrfs_inode_hash(BTRFS_BTREE_INODE_OBJECTID,
1920					      fs_info->tree_root);
1921	struct inode *inode;
1922
1923	inode = new_inode(sb);
1924	if (!inode)
1925		return -ENOMEM;
1926
1927	inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
1928	set_nlink(inode, 1);
1929	/*
1930	 * we set the i_size on the btree inode to the max possible int.
1931	 * the real end of the address space is determined by all of
1932	 * the devices in the system
1933	 */
1934	inode->i_size = OFFSET_MAX;
1935	inode->i_mapping->a_ops = &btree_aops;
1936	mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
1937
1938	RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
1939	extent_io_tree_init(fs_info, &BTRFS_I(inode)->io_tree,
1940			    IO_TREE_BTREE_INODE_IO);
1941	extent_map_tree_init(&BTRFS_I(inode)->extent_tree);
1942
1943	BTRFS_I(inode)->root = btrfs_grab_root(fs_info->tree_root);
1944	BTRFS_I(inode)->location.objectid = BTRFS_BTREE_INODE_OBJECTID;
1945	BTRFS_I(inode)->location.type = 0;
1946	BTRFS_I(inode)->location.offset = 0;
1947	set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
1948	__insert_inode_hash(inode, hash);
1949	fs_info->btree_inode = inode;
1950
1951	return 0;
1952}
1953
1954static void btrfs_init_dev_replace_locks(struct btrfs_fs_info *fs_info)
1955{
1956	mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount);
1957	init_rwsem(&fs_info->dev_replace.rwsem);
1958	init_waitqueue_head(&fs_info->dev_replace.replace_wait);
1959}
1960
1961static void btrfs_init_qgroup(struct btrfs_fs_info *fs_info)
1962{
1963	spin_lock_init(&fs_info->qgroup_lock);
1964	mutex_init(&fs_info->qgroup_ioctl_lock);
1965	fs_info->qgroup_tree = RB_ROOT;
1966	INIT_LIST_HEAD(&fs_info->dirty_qgroups);
1967	fs_info->qgroup_seq = 1;
1968	fs_info->qgroup_ulist = NULL;
1969	fs_info->qgroup_rescan_running = false;
1970	fs_info->qgroup_drop_subtree_thres = BTRFS_MAX_LEVEL;
1971	mutex_init(&fs_info->qgroup_rescan_lock);
1972}
1973
1974static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info)
1975{
1976	u32 max_active = fs_info->thread_pool_size;
1977	unsigned int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND;
1978	unsigned int ordered_flags = WQ_MEM_RECLAIM | WQ_FREEZABLE;
1979
1980	fs_info->workers =
1981		btrfs_alloc_workqueue(fs_info, "worker", flags, max_active, 16);
1982
1983	fs_info->delalloc_workers =
1984		btrfs_alloc_workqueue(fs_info, "delalloc",
1985				      flags, max_active, 2);
1986
1987	fs_info->flush_workers =
1988		btrfs_alloc_workqueue(fs_info, "flush_delalloc",
1989				      flags, max_active, 0);
1990
1991	fs_info->caching_workers =
1992		btrfs_alloc_workqueue(fs_info, "cache", flags, max_active, 0);
1993
1994	fs_info->fixup_workers =
1995		btrfs_alloc_ordered_workqueue(fs_info, "fixup", ordered_flags);
1996
1997	fs_info->endio_workers =
1998		alloc_workqueue("btrfs-endio", flags, max_active);
1999	fs_info->endio_meta_workers =
2000		alloc_workqueue("btrfs-endio-meta", flags, max_active);
2001	fs_info->rmw_workers = alloc_workqueue("btrfs-rmw", flags, max_active);
2002	fs_info->endio_write_workers =
2003		btrfs_alloc_workqueue(fs_info, "endio-write", flags,
2004				      max_active, 2);
2005	fs_info->compressed_write_workers =
2006		alloc_workqueue("btrfs-compressed-write", flags, max_active);
2007	fs_info->endio_freespace_worker =
2008		btrfs_alloc_workqueue(fs_info, "freespace-write", flags,
2009				      max_active, 0);
2010	fs_info->delayed_workers =
2011		btrfs_alloc_workqueue(fs_info, "delayed-meta", flags,
2012				      max_active, 0);
2013	fs_info->qgroup_rescan_workers =
2014		btrfs_alloc_ordered_workqueue(fs_info, "qgroup-rescan",
2015					      ordered_flags);
2016	fs_info->discard_ctl.discard_workers =
2017		alloc_ordered_workqueue("btrfs_discard", WQ_FREEZABLE);
2018
2019	if (!(fs_info->workers &&
2020	      fs_info->delalloc_workers && fs_info->flush_workers &&
2021	      fs_info->endio_workers && fs_info->endio_meta_workers &&
2022	      fs_info->compressed_write_workers &&
2023	      fs_info->endio_write_workers &&
2024	      fs_info->endio_freespace_worker && fs_info->rmw_workers &&
2025	      fs_info->caching_workers && fs_info->fixup_workers &&
2026	      fs_info->delayed_workers && fs_info->qgroup_rescan_workers &&
2027	      fs_info->discard_ctl.discard_workers)) {
2028		return -ENOMEM;
2029	}
2030
2031	return 0;
2032}
2033
2034static int btrfs_init_csum_hash(struct btrfs_fs_info *fs_info, u16 csum_type)
2035{
2036	struct crypto_shash *csum_shash;
2037	const char *csum_driver = btrfs_super_csum_driver(csum_type);
2038
2039	csum_shash = crypto_alloc_shash(csum_driver, 0, 0);
2040
2041	if (IS_ERR(csum_shash)) {
2042		btrfs_err(fs_info, "error allocating %s hash for checksum",
2043			  csum_driver);
2044		return PTR_ERR(csum_shash);
2045	}
2046
2047	fs_info->csum_shash = csum_shash;
2048
2049	/*
2050	 * Check if the checksum implementation is a fast accelerated one.
2051	 * As-is this is a bit of a hack and should be replaced once the csum
2052	 * implementations provide that information themselves.
2053	 */
2054	switch (csum_type) {
2055	case BTRFS_CSUM_TYPE_CRC32:
2056		if (!strstr(crypto_shash_driver_name(csum_shash), "generic"))
2057			set_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags);
2058		break;
2059	case BTRFS_CSUM_TYPE_XXHASH:
2060		set_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags);
2061		break;
2062	default:
2063		break;
2064	}
2065
2066	btrfs_info(fs_info, "using %s (%s) checksum algorithm",
2067			btrfs_super_csum_name(csum_type),
2068			crypto_shash_driver_name(csum_shash));
2069	return 0;
2070}
2071
2072static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
2073			    struct btrfs_fs_devices *fs_devices)
2074{
2075	int ret;
2076	struct btrfs_tree_parent_check check = { 0 };
2077	struct btrfs_root *log_tree_root;
2078	struct btrfs_super_block *disk_super = fs_info->super_copy;
2079	u64 bytenr = btrfs_super_log_root(disk_super);
2080	int level = btrfs_super_log_root_level(disk_super);
2081
2082	if (fs_devices->rw_devices == 0) {
2083		btrfs_warn(fs_info, "log replay required on RO media");
2084		return -EIO;
2085	}
2086
2087	log_tree_root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID,
2088					 GFP_KERNEL);
2089	if (!log_tree_root)
2090		return -ENOMEM;
2091
2092	check.level = level;
2093	check.transid = fs_info->generation + 1;
2094	check.owner_root = BTRFS_TREE_LOG_OBJECTID;
2095	log_tree_root->node = read_tree_block(fs_info, bytenr, &check);
2096	if (IS_ERR(log_tree_root->node)) {
2097		btrfs_warn(fs_info, "failed to read log tree");
2098		ret = PTR_ERR(log_tree_root->node);
2099		log_tree_root->node = NULL;
2100		btrfs_put_root(log_tree_root);
2101		return ret;
2102	}
2103	if (!extent_buffer_uptodate(log_tree_root->node)) {
2104		btrfs_err(fs_info, "failed to read log tree");
2105		btrfs_put_root(log_tree_root);
2106		return -EIO;
2107	}
2108
2109	/* returns with log_tree_root freed on success */
2110	ret = btrfs_recover_log_trees(log_tree_root);
2111	if (ret) {
2112		btrfs_handle_fs_error(fs_info, ret,
2113				      "Failed to recover log tree");
2114		btrfs_put_root(log_tree_root);
2115		return ret;
2116	}
2117
2118	if (sb_rdonly(fs_info->sb)) {
2119		ret = btrfs_commit_super(fs_info);
2120		if (ret)
2121			return ret;
2122	}
2123
2124	return 0;
2125}
2126
2127static int load_global_roots_objectid(struct btrfs_root *tree_root,
2128				      struct btrfs_path *path, u64 objectid,
2129				      const char *name)
2130{
2131	struct btrfs_fs_info *fs_info = tree_root->fs_info;
2132	struct btrfs_root *root;
2133	u64 max_global_id = 0;
2134	int ret;
2135	struct btrfs_key key = {
2136		.objectid = objectid,
2137		.type = BTRFS_ROOT_ITEM_KEY,
2138		.offset = 0,
2139	};
2140	bool found = false;
2141
2142	/* If we have IGNOREDATACSUMS skip loading these roots. */
2143	if (objectid == BTRFS_CSUM_TREE_OBJECTID &&
2144	    btrfs_test_opt(fs_info, IGNOREDATACSUMS)) {
2145		set_bit(BTRFS_FS_STATE_NO_CSUMS, &fs_info->fs_state);
2146		return 0;
2147	}
2148
2149	while (1) {
2150		ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0);
2151		if (ret < 0)
2152			break;
2153
2154		if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
2155			ret = btrfs_next_leaf(tree_root, path);
2156			if (ret) {
2157				if (ret > 0)
2158					ret = 0;
2159				break;
2160			}
2161		}
2162		ret = 0;
2163
2164		btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
2165		if (key.objectid != objectid)
2166			break;
2167		btrfs_release_path(path);
2168
2169		/*
2170		 * Just worry about this for extent tree, it'll be the same for
2171		 * everybody.
2172		 */
2173		if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
2174			max_global_id = max(max_global_id, key.offset);
2175
2176		found = true;
2177		root = read_tree_root_path(tree_root, path, &key);
2178		if (IS_ERR(root)) {
2179			if (!btrfs_test_opt(fs_info, IGNOREBADROOTS))
2180				ret = PTR_ERR(root);
2181			break;
2182		}
2183		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2184		ret = btrfs_global_root_insert(root);
2185		if (ret) {
2186			btrfs_put_root(root);
2187			break;
2188		}
2189		key.offset++;
2190	}
2191	btrfs_release_path(path);
2192
2193	if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
2194		fs_info->nr_global_roots = max_global_id + 1;
2195
2196	if (!found || ret) {
2197		if (objectid == BTRFS_CSUM_TREE_OBJECTID)
2198			set_bit(BTRFS_FS_STATE_NO_CSUMS, &fs_info->fs_state);
2199
2200		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS))
2201			ret = ret ? ret : -ENOENT;
2202		else
2203			ret = 0;
2204		btrfs_err(fs_info, "failed to load root %s", name);
2205	}
2206	return ret;
2207}
2208
2209static int load_global_roots(struct btrfs_root *tree_root)
2210{
2211	struct btrfs_path *path;
2212	int ret = 0;
2213
2214	path = btrfs_alloc_path();
2215	if (!path)
2216		return -ENOMEM;
2217
2218	ret = load_global_roots_objectid(tree_root, path,
2219					 BTRFS_EXTENT_TREE_OBJECTID, "extent");
2220	if (ret)
2221		goto out;
2222	ret = load_global_roots_objectid(tree_root, path,
2223					 BTRFS_CSUM_TREE_OBJECTID, "csum");
2224	if (ret)
2225		goto out;
2226	if (!btrfs_fs_compat_ro(tree_root->fs_info, FREE_SPACE_TREE))
2227		goto out;
2228	ret = load_global_roots_objectid(tree_root, path,
2229					 BTRFS_FREE_SPACE_TREE_OBJECTID,
2230					 "free space");
2231out:
2232	btrfs_free_path(path);
2233	return ret;
2234}
2235
2236static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
2237{
2238	struct btrfs_root *tree_root = fs_info->tree_root;
2239	struct btrfs_root *root;
2240	struct btrfs_key location;
2241	int ret;
2242
2243	ASSERT(fs_info->tree_root);
2244
2245	ret = load_global_roots(tree_root);
2246	if (ret)
2247		return ret;
2248
2249	location.type = BTRFS_ROOT_ITEM_KEY;
2250	location.offset = 0;
2251
2252	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE)) {
2253		location.objectid = BTRFS_BLOCK_GROUP_TREE_OBJECTID;
2254		root = btrfs_read_tree_root(tree_root, &location);
2255		if (IS_ERR(root)) {
2256			if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2257				ret = PTR_ERR(root);
2258				goto out;
2259			}
2260		} else {
2261			set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2262			fs_info->block_group_root = root;
2263		}
2264	}
2265
2266	location.objectid = BTRFS_DEV_TREE_OBJECTID;
2267	root = btrfs_read_tree_root(tree_root, &location);
2268	if (IS_ERR(root)) {
2269		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2270			ret = PTR_ERR(root);
2271			goto out;
2272		}
2273	} else {
2274		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2275		fs_info->dev_root = root;
2276	}
2277	/* Initialize fs_info for all devices in any case */
2278	ret = btrfs_init_devices_late(fs_info);
2279	if (ret)
2280		goto out;
2281
2282	/*
2283	 * This tree can share blocks with some other fs tree during relocation
2284	 * and we need a proper setup by btrfs_get_fs_root
2285	 */
2286	root = btrfs_get_fs_root(tree_root->fs_info,
2287				 BTRFS_DATA_RELOC_TREE_OBJECTID, true);
2288	if (IS_ERR(root)) {
2289		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2290			ret = PTR_ERR(root);
2291			goto out;
2292		}
2293	} else {
2294		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2295		fs_info->data_reloc_root = root;
2296	}
2297
2298	location.objectid = BTRFS_QUOTA_TREE_OBJECTID;
2299	root = btrfs_read_tree_root(tree_root, &location);
2300	if (!IS_ERR(root)) {
2301		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2302		fs_info->quota_root = root;
2303	}
2304
2305	location.objectid = BTRFS_UUID_TREE_OBJECTID;
2306	root = btrfs_read_tree_root(tree_root, &location);
2307	if (IS_ERR(root)) {
2308		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2309			ret = PTR_ERR(root);
2310			if (ret != -ENOENT)
2311				goto out;
2312		}
2313	} else {
2314		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2315		fs_info->uuid_root = root;
2316	}
2317
2318	if (btrfs_fs_incompat(fs_info, RAID_STRIPE_TREE)) {
2319		location.objectid = BTRFS_RAID_STRIPE_TREE_OBJECTID;
2320		root = btrfs_read_tree_root(tree_root, &location);
2321		if (IS_ERR(root)) {
2322			if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2323				ret = PTR_ERR(root);
2324				goto out;
2325			}
2326		} else {
2327			set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2328			fs_info->stripe_root = root;
2329		}
2330	}
2331
2332	return 0;
2333out:
2334	btrfs_warn(fs_info, "failed to read root (objectid=%llu): %d",
2335		   location.objectid, ret);
2336	return ret;
2337}
2338
2339/*
2340 * Real super block validation
2341 * NOTE: super csum type and incompat features will not be checked here.
2342 *
2343 * @sb:		super block to check
2344 * @mirror_num:	the super block number to check its bytenr:
2345 * 		0	the primary (1st) sb
2346 * 		1, 2	2nd and 3rd backup copy
2347 * 	       -1	skip bytenr check
2348 */
2349int btrfs_validate_super(struct btrfs_fs_info *fs_info,
2350			 struct btrfs_super_block *sb, int mirror_num)
2351{
2352	u64 nodesize = btrfs_super_nodesize(sb);
2353	u64 sectorsize = btrfs_super_sectorsize(sb);
2354	int ret = 0;
2355
2356	if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
2357		btrfs_err(fs_info, "no valid FS found");
2358		ret = -EINVAL;
2359	}
2360	if (btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP) {
2361		btrfs_err(fs_info, "unrecognized or unsupported super flag: %llu",
2362				btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);
2363		ret = -EINVAL;
2364	}
2365	if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
2366		btrfs_err(fs_info, "tree_root level too big: %d >= %d",
2367				btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
2368		ret = -EINVAL;
2369	}
2370	if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
2371		btrfs_err(fs_info, "chunk_root level too big: %d >= %d",
2372				btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
2373		ret = -EINVAL;
2374	}
2375	if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
2376		btrfs_err(fs_info, "log_root level too big: %d >= %d",
2377				btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
2378		ret = -EINVAL;
2379	}
2380
2381	/*
2382	 * Check sectorsize and nodesize first, other check will need it.
2383	 * Check all possible sectorsize(4K, 8K, 16K, 32K, 64K) here.
2384	 */
2385	if (!is_power_of_2(sectorsize) || sectorsize < 4096 ||
2386	    sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2387		btrfs_err(fs_info, "invalid sectorsize %llu", sectorsize);
2388		ret = -EINVAL;
2389	}
2390
2391	/*
2392	 * We only support at most two sectorsizes: 4K and PAGE_SIZE.
2393	 *
2394	 * We can support 16K sectorsize with 64K page size without problem,
2395	 * but such sectorsize/pagesize combination doesn't make much sense.
2396	 * 4K will be our future standard, PAGE_SIZE is supported from the very
2397	 * beginning.
2398	 */
2399	if (sectorsize > PAGE_SIZE || (sectorsize != SZ_4K && sectorsize != PAGE_SIZE)) {
2400		btrfs_err(fs_info,
2401			"sectorsize %llu not yet supported for page size %lu",
2402			sectorsize, PAGE_SIZE);
2403		ret = -EINVAL;
2404	}
2405
2406	if (!is_power_of_2(nodesize) || nodesize < sectorsize ||
2407	    nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2408		btrfs_err(fs_info, "invalid nodesize %llu", nodesize);
2409		ret = -EINVAL;
2410	}
2411	if (nodesize != le32_to_cpu(sb->__unused_leafsize)) {
2412		btrfs_err(fs_info, "invalid leafsize %u, should be %llu",
2413			  le32_to_cpu(sb->__unused_leafsize), nodesize);
2414		ret = -EINVAL;
2415	}
2416
2417	/* Root alignment check */
2418	if (!IS_ALIGNED(btrfs_super_root(sb), sectorsize)) {
2419		btrfs_warn(fs_info, "tree_root block unaligned: %llu",
2420			   btrfs_super_root(sb));
2421		ret = -EINVAL;
2422	}
2423	if (!IS_ALIGNED(btrfs_super_chunk_root(sb), sectorsize)) {
2424		btrfs_warn(fs_info, "chunk_root block unaligned: %llu",
2425			   btrfs_super_chunk_root(sb));
2426		ret = -EINVAL;
2427	}
2428	if (!IS_ALIGNED(btrfs_super_log_root(sb), sectorsize)) {
2429		btrfs_warn(fs_info, "log_root block unaligned: %llu",
2430			   btrfs_super_log_root(sb));
2431		ret = -EINVAL;
2432	}
2433
2434	if (!fs_info->fs_devices->temp_fsid &&
2435	    memcmp(fs_info->fs_devices->fsid, sb->fsid, BTRFS_FSID_SIZE) != 0) {
2436		btrfs_err(fs_info,
2437		"superblock fsid doesn't match fsid of fs_devices: %pU != %pU",
2438			  sb->fsid, fs_info->fs_devices->fsid);
2439		ret = -EINVAL;
2440	}
2441
2442	if (memcmp(fs_info->fs_devices->metadata_uuid, btrfs_sb_fsid_ptr(sb),
2443		   BTRFS_FSID_SIZE) != 0) {
2444		btrfs_err(fs_info,
2445"superblock metadata_uuid doesn't match metadata uuid of fs_devices: %pU != %pU",
2446			  btrfs_sb_fsid_ptr(sb), fs_info->fs_devices->metadata_uuid);
2447		ret = -EINVAL;
2448	}
2449
2450	if (memcmp(fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid,
2451		   BTRFS_FSID_SIZE) != 0) {
2452		btrfs_err(fs_info,
2453			"dev_item UUID does not match metadata fsid: %pU != %pU",
2454			fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid);
2455		ret = -EINVAL;
2456	}
2457
2458	/*
2459	 * Artificial requirement for block-group-tree to force newer features
2460	 * (free-space-tree, no-holes) so the test matrix is smaller.
2461	 */
2462	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE) &&
2463	    (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID) ||
2464	     !btrfs_fs_incompat(fs_info, NO_HOLES))) {
2465		btrfs_err(fs_info,
2466		"block-group-tree feature requires fres-space-tree and no-holes");
2467		ret = -EINVAL;
2468	}
2469
2470	/*
2471	 * Hint to catch really bogus numbers, bitflips or so, more exact checks are
2472	 * done later
2473	 */
2474	if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) {
2475		btrfs_err(fs_info, "bytes_used is too small %llu",
2476			  btrfs_super_bytes_used(sb));
2477		ret = -EINVAL;
2478	}
2479	if (!is_power_of_2(btrfs_super_stripesize(sb))) {
2480		btrfs_err(fs_info, "invalid stripesize %u",
2481			  btrfs_super_stripesize(sb));
2482		ret = -EINVAL;
2483	}
2484	if (btrfs_super_num_devices(sb) > (1UL << 31))
2485		btrfs_warn(fs_info, "suspicious number of devices: %llu",
2486			   btrfs_super_num_devices(sb));
2487	if (btrfs_super_num_devices(sb) == 0) {
2488		btrfs_err(fs_info, "number of devices is 0");
2489		ret = -EINVAL;
2490	}
2491
2492	if (mirror_num >= 0 &&
2493	    btrfs_super_bytenr(sb) != btrfs_sb_offset(mirror_num)) {
2494		btrfs_err(fs_info, "super offset mismatch %llu != %u",
2495			  btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET);
2496		ret = -EINVAL;
2497	}
2498
2499	/*
2500	 * Obvious sys_chunk_array corruptions, it must hold at least one key
2501	 * and one chunk
2502	 */
2503	if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
2504		btrfs_err(fs_info, "system chunk array too big %u > %u",
2505			  btrfs_super_sys_array_size(sb),
2506			  BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
2507		ret = -EINVAL;
2508	}
2509	if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
2510			+ sizeof(struct btrfs_chunk)) {
2511		btrfs_err(fs_info, "system chunk array too small %u < %zu",
2512			  btrfs_super_sys_array_size(sb),
2513			  sizeof(struct btrfs_disk_key)
2514			  + sizeof(struct btrfs_chunk));
2515		ret = -EINVAL;
2516	}
2517
2518	/*
2519	 * The generation is a global counter, we'll trust it more than the others
2520	 * but it's still possible that it's the one that's wrong.
2521	 */
2522	if (btrfs_super_generation(sb) < btrfs_super_chunk_root_generation(sb))
2523		btrfs_warn(fs_info,
2524			"suspicious: generation < chunk_root_generation: %llu < %llu",
2525			btrfs_super_generation(sb),
2526			btrfs_super_chunk_root_generation(sb));
2527	if (btrfs_super_generation(sb) < btrfs_super_cache_generation(sb)
2528	    && btrfs_super_cache_generation(sb) != (u64)-1)
2529		btrfs_warn(fs_info,
2530			"suspicious: generation < cache_generation: %llu < %llu",
2531			btrfs_super_generation(sb),
2532			btrfs_super_cache_generation(sb));
2533
2534	return ret;
2535}
2536
2537/*
2538 * Validation of super block at mount time.
2539 * Some checks already done early at mount time, like csum type and incompat
2540 * flags will be skipped.
2541 */
2542static int btrfs_validate_mount_super(struct btrfs_fs_info *fs_info)
2543{
2544	return btrfs_validate_super(fs_info, fs_info->super_copy, 0);
2545}
2546
2547/*
2548 * Validation of super block at write time.
2549 * Some checks like bytenr check will be skipped as their values will be
2550 * overwritten soon.
2551 * Extra checks like csum type and incompat flags will be done here.
2552 */
2553static int btrfs_validate_write_super(struct btrfs_fs_info *fs_info,
2554				      struct btrfs_super_block *sb)
2555{
2556	int ret;
2557
2558	ret = btrfs_validate_super(fs_info, sb, -1);
2559	if (ret < 0)
2560		goto out;
2561	if (!btrfs_supported_super_csum(btrfs_super_csum_type(sb))) {
2562		ret = -EUCLEAN;
2563		btrfs_err(fs_info, "invalid csum type, has %u want %u",
2564			  btrfs_super_csum_type(sb), BTRFS_CSUM_TYPE_CRC32);
2565		goto out;
2566	}
2567	if (btrfs_super_incompat_flags(sb) & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
2568		ret = -EUCLEAN;
2569		btrfs_err(fs_info,
2570		"invalid incompat flags, has 0x%llx valid mask 0x%llx",
2571			  btrfs_super_incompat_flags(sb),
2572			  (unsigned long long)BTRFS_FEATURE_INCOMPAT_SUPP);
2573		goto out;
2574	}
2575out:
2576	if (ret < 0)
2577		btrfs_err(fs_info,
2578		"super block corruption detected before writing it to disk");
2579	return ret;
2580}
2581
2582static int load_super_root(struct btrfs_root *root, u64 bytenr, u64 gen, int level)
2583{
2584	struct btrfs_tree_parent_check check = {
2585		.level = level,
2586		.transid = gen,
2587		.owner_root = root->root_key.objectid
2588	};
2589	int ret = 0;
2590
2591	root->node = read_tree_block(root->fs_info, bytenr, &check);
2592	if (IS_ERR(root->node)) {
2593		ret = PTR_ERR(root->node);
2594		root->node = NULL;
2595		return ret;
2596	}
2597	if (!extent_buffer_uptodate(root->node)) {
2598		free_extent_buffer(root->node);
2599		root->node = NULL;
2600		return -EIO;
2601	}
2602
2603	btrfs_set_root_node(&root->root_item, root->node);
2604	root->commit_root = btrfs_root_node(root);
2605	btrfs_set_root_refs(&root->root_item, 1);
2606	return ret;
2607}
2608
2609static int load_important_roots(struct btrfs_fs_info *fs_info)
2610{
2611	struct btrfs_super_block *sb = fs_info->super_copy;
2612	u64 gen, bytenr;
2613	int level, ret;
2614
2615	bytenr = btrfs_super_root(sb);
2616	gen = btrfs_super_generation(sb);
2617	level = btrfs_super_root_level(sb);
2618	ret = load_super_root(fs_info->tree_root, bytenr, gen, level);
2619	if (ret) {
2620		btrfs_warn(fs_info, "couldn't read tree root");
2621		return ret;
2622	}
2623	return 0;
2624}
2625
2626static int __cold init_tree_roots(struct btrfs_fs_info *fs_info)
2627{
2628	int backup_index = find_newest_super_backup(fs_info);
2629	struct btrfs_super_block *sb = fs_info->super_copy;
2630	struct btrfs_root *tree_root = fs_info->tree_root;
2631	bool handle_error = false;
2632	int ret = 0;
2633	int i;
2634
2635	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
2636		if (handle_error) {
2637			if (!IS_ERR(tree_root->node))
2638				free_extent_buffer(tree_root->node);
2639			tree_root->node = NULL;
2640
2641			if (!btrfs_test_opt(fs_info, USEBACKUPROOT))
2642				break;
2643
2644			free_root_pointers(fs_info, 0);
2645
2646			/*
2647			 * Don't use the log in recovery mode, it won't be
2648			 * valid
2649			 */
2650			btrfs_set_super_log_root(sb, 0);
2651
2652			btrfs_warn(fs_info, "try to load backup roots slot %d", i);
2653			ret = read_backup_root(fs_info, i);
2654			backup_index = ret;
2655			if (ret < 0)
2656				return ret;
2657		}
2658
2659		ret = load_important_roots(fs_info);
2660		if (ret) {
2661			handle_error = true;
2662			continue;
2663		}
2664
2665		/*
2666		 * No need to hold btrfs_root::objectid_mutex since the fs
2667		 * hasn't been fully initialised and we are the only user
2668		 */
2669		ret = btrfs_init_root_free_objectid(tree_root);
2670		if (ret < 0) {
2671			handle_error = true;
2672			continue;
2673		}
2674
2675		ASSERT(tree_root->free_objectid <= BTRFS_LAST_FREE_OBJECTID);
2676
2677		ret = btrfs_read_roots(fs_info);
2678		if (ret < 0) {
2679			handle_error = true;
2680			continue;
2681		}
2682
2683		/* All successful */
2684		fs_info->generation = btrfs_header_generation(tree_root->node);
2685		btrfs_set_last_trans_committed(fs_info, fs_info->generation);
2686		fs_info->last_reloc_trans = 0;
2687
2688		/* Always begin writing backup roots after the one being used */
2689		if (backup_index < 0) {
2690			fs_info->backup_root_index = 0;
2691		} else {
2692			fs_info->backup_root_index = backup_index + 1;
2693			fs_info->backup_root_index %= BTRFS_NUM_BACKUP_ROOTS;
2694		}
2695		break;
2696	}
2697
2698	return ret;
2699}
2700
2701void btrfs_init_fs_info(struct btrfs_fs_info *fs_info)
2702{
2703	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
2704	INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC);
2705	INIT_LIST_HEAD(&fs_info->trans_list);
2706	INIT_LIST_HEAD(&fs_info->dead_roots);
2707	INIT_LIST_HEAD(&fs_info->delayed_iputs);
2708	INIT_LIST_HEAD(&fs_info->delalloc_roots);
 
 
2709	INIT_LIST_HEAD(&fs_info->caching_block_groups);
2710	spin_lock_init(&fs_info->delalloc_root_lock);
2711	spin_lock_init(&fs_info->trans_lock);
 
2712	spin_lock_init(&fs_info->fs_roots_radix_lock);
2713	spin_lock_init(&fs_info->delayed_iput_lock);
2714	spin_lock_init(&fs_info->defrag_inodes_lock);
2715	spin_lock_init(&fs_info->super_lock);
2716	spin_lock_init(&fs_info->buffer_lock);
2717	spin_lock_init(&fs_info->unused_bgs_lock);
2718	spin_lock_init(&fs_info->treelog_bg_lock);
2719	spin_lock_init(&fs_info->zone_active_bgs_lock);
2720	spin_lock_init(&fs_info->relocation_bg_lock);
2721	rwlock_init(&fs_info->tree_mod_log_lock);
2722	rwlock_init(&fs_info->global_root_lock);
2723	mutex_init(&fs_info->unused_bg_unpin_mutex);
2724	mutex_init(&fs_info->reclaim_bgs_lock);
2725	mutex_init(&fs_info->reloc_mutex);
2726	mutex_init(&fs_info->delalloc_root_mutex);
2727	mutex_init(&fs_info->zoned_meta_io_lock);
2728	mutex_init(&fs_info->zoned_data_reloc_io_lock);
2729	seqlock_init(&fs_info->profiles_lock);
2730
2731	btrfs_lockdep_init_map(fs_info, btrfs_trans_num_writers);
2732	btrfs_lockdep_init_map(fs_info, btrfs_trans_num_extwriters);
2733	btrfs_lockdep_init_map(fs_info, btrfs_trans_pending_ordered);
2734	btrfs_lockdep_init_map(fs_info, btrfs_ordered_extent);
2735	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_commit_prep,
2736				     BTRFS_LOCKDEP_TRANS_COMMIT_PREP);
2737	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_unblocked,
2738				     BTRFS_LOCKDEP_TRANS_UNBLOCKED);
2739	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_super_committed,
2740				     BTRFS_LOCKDEP_TRANS_SUPER_COMMITTED);
2741	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_completed,
2742				     BTRFS_LOCKDEP_TRANS_COMPLETED);
2743
 
 
 
 
 
 
 
2744	INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
2745	INIT_LIST_HEAD(&fs_info->space_info);
2746	INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
2747	INIT_LIST_HEAD(&fs_info->unused_bgs);
2748	INIT_LIST_HEAD(&fs_info->reclaim_bgs);
2749	INIT_LIST_HEAD(&fs_info->zone_active_bgs);
2750#ifdef CONFIG_BTRFS_DEBUG
2751	INIT_LIST_HEAD(&fs_info->allocated_roots);
2752	INIT_LIST_HEAD(&fs_info->allocated_ebs);
2753	spin_lock_init(&fs_info->eb_leak_lock);
2754#endif
2755	fs_info->mapping_tree = RB_ROOT_CACHED;
2756	rwlock_init(&fs_info->mapping_tree_lock);
2757	btrfs_init_block_rsv(&fs_info->global_block_rsv,
2758			     BTRFS_BLOCK_RSV_GLOBAL);
2759	btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
2760	btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK);
2761	btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY);
2762	btrfs_init_block_rsv(&fs_info->delayed_block_rsv,
2763			     BTRFS_BLOCK_RSV_DELOPS);
2764	btrfs_init_block_rsv(&fs_info->delayed_refs_rsv,
2765			     BTRFS_BLOCK_RSV_DELREFS);
2766
2767	atomic_set(&fs_info->async_delalloc_pages, 0);
 
 
2768	atomic_set(&fs_info->defrag_running, 0);
2769	atomic_set(&fs_info->nr_delayed_iputs, 0);
2770	atomic64_set(&fs_info->tree_mod_seq, 0);
2771	fs_info->global_root_tree = RB_ROOT;
2772	fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE;
2773	fs_info->metadata_ratio = 0;
2774	fs_info->defrag_inodes = RB_ROOT;
2775	atomic64_set(&fs_info->free_chunk_space, 0);
2776	fs_info->tree_mod_log = RB_ROOT;
2777	fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
2778	btrfs_init_ref_verify(fs_info);
2779
2780	fs_info->thread_pool_size = min_t(unsigned long,
2781					  num_online_cpus() + 2, 8);
2782
2783	INIT_LIST_HEAD(&fs_info->ordered_roots);
2784	spin_lock_init(&fs_info->ordered_root_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2785
2786	btrfs_init_scrub(fs_info);
2787	btrfs_init_balance(fs_info);
2788	btrfs_init_async_reclaim_work(fs_info);
2789
2790	rwlock_init(&fs_info->block_group_cache_lock);
2791	fs_info->block_group_cache_tree = RB_ROOT_CACHED;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2792
2793	extent_io_tree_init(fs_info, &fs_info->excluded_extents,
2794			    IO_TREE_FS_EXCLUDED_EXTENTS);
2795
2796	mutex_init(&fs_info->ordered_operations_mutex);
2797	mutex_init(&fs_info->tree_log_mutex);
2798	mutex_init(&fs_info->chunk_mutex);
2799	mutex_init(&fs_info->transaction_kthread_mutex);
2800	mutex_init(&fs_info->cleaner_mutex);
2801	mutex_init(&fs_info->ro_block_group_mutex);
2802	init_rwsem(&fs_info->commit_root_sem);
2803	init_rwsem(&fs_info->cleanup_work_sem);
2804	init_rwsem(&fs_info->subvol_sem);
2805	sema_init(&fs_info->uuid_tree_rescan_sem, 1);
2806
2807	btrfs_init_dev_replace_locks(fs_info);
2808	btrfs_init_qgroup(fs_info);
2809	btrfs_discard_init(fs_info);
2810
2811	btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
2812	btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
2813
2814	init_waitqueue_head(&fs_info->transaction_throttle);
2815	init_waitqueue_head(&fs_info->transaction_wait);
2816	init_waitqueue_head(&fs_info->transaction_blocked_wait);
2817	init_waitqueue_head(&fs_info->async_submit_wait);
2818	init_waitqueue_head(&fs_info->delayed_iputs_wait);
2819
2820	/* Usable values until the real ones are cached from the superblock */
2821	fs_info->nodesize = 4096;
2822	fs_info->sectorsize = 4096;
2823	fs_info->sectorsize_bits = ilog2(4096);
2824	fs_info->stripesize = 4096;
2825
2826	/* Default compress algorithm when user does -o compress */
2827	fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
2828
2829	fs_info->max_extent_size = BTRFS_MAX_EXTENT_SIZE;
2830
2831	spin_lock_init(&fs_info->swapfile_pins_lock);
2832	fs_info->swapfile_pins = RB_ROOT;
2833
2834	fs_info->bg_reclaim_threshold = BTRFS_DEFAULT_RECLAIM_THRESH;
2835	INIT_WORK(&fs_info->reclaim_bgs_work, btrfs_reclaim_bgs_work);
2836}
2837
2838static int init_mount_fs_info(struct btrfs_fs_info *fs_info, struct super_block *sb)
2839{
2840	int ret;
2841
2842	fs_info->sb = sb;
2843	/* Temporary fixed values for block size until we read the superblock. */
2844	sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE;
2845	sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE);
2846
2847	ret = percpu_counter_init(&fs_info->ordered_bytes, 0, GFP_KERNEL);
2848	if (ret)
2849		return ret;
2850
2851	ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0, GFP_KERNEL);
2852	if (ret)
2853		return ret;
2854
2855	fs_info->dirty_metadata_batch = PAGE_SIZE *
2856					(1 + ilog2(nr_cpu_ids));
2857
2858	ret = percpu_counter_init(&fs_info->delalloc_bytes, 0, GFP_KERNEL);
2859	if (ret)
2860		return ret;
2861
2862	ret = percpu_counter_init(&fs_info->dev_replace.bio_counter, 0,
2863			GFP_KERNEL);
2864	if (ret)
2865		return ret;
2866
2867	fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
2868					GFP_KERNEL);
2869	if (!fs_info->delayed_root)
2870		return -ENOMEM;
2871	btrfs_init_delayed_root(fs_info->delayed_root);
2872
2873	if (sb_rdonly(sb))
2874		set_bit(BTRFS_FS_STATE_RO, &fs_info->fs_state);
2875
2876	return btrfs_alloc_stripe_hash_table(fs_info);
2877}
2878
2879static int btrfs_uuid_rescan_kthread(void *data)
2880{
2881	struct btrfs_fs_info *fs_info = data;
2882	int ret;
2883
2884	/*
2885	 * 1st step is to iterate through the existing UUID tree and
2886	 * to delete all entries that contain outdated data.
2887	 * 2nd step is to add all missing entries to the UUID tree.
2888	 */
2889	ret = btrfs_uuid_tree_iterate(fs_info);
2890	if (ret < 0) {
2891		if (ret != -EINTR)
2892			btrfs_warn(fs_info, "iterating uuid_tree failed %d",
2893				   ret);
2894		up(&fs_info->uuid_tree_rescan_sem);
2895		return ret;
2896	}
2897	return btrfs_uuid_scan_kthread(data);
2898}
2899
2900static int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
2901{
2902	struct task_struct *task;
2903
2904	down(&fs_info->uuid_tree_rescan_sem);
2905	task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
2906	if (IS_ERR(task)) {
2907		/* fs_info->update_uuid_tree_gen remains 0 in all error case */
2908		btrfs_warn(fs_info, "failed to start uuid_rescan task");
2909		up(&fs_info->uuid_tree_rescan_sem);
2910		return PTR_ERR(task);
2911	}
2912
2913	return 0;
2914}
2915
2916static int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
2917{
2918	u64 root_objectid = 0;
2919	struct btrfs_root *gang[8];
2920	int i = 0;
2921	int err = 0;
2922	unsigned int ret = 0;
2923
2924	while (1) {
2925		spin_lock(&fs_info->fs_roots_radix_lock);
2926		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2927					     (void **)gang, root_objectid,
2928					     ARRAY_SIZE(gang));
2929		if (!ret) {
2930			spin_unlock(&fs_info->fs_roots_radix_lock);
2931			break;
2932		}
2933		root_objectid = gang[ret - 1]->root_key.objectid + 1;
2934
2935		for (i = 0; i < ret; i++) {
2936			/* Avoid to grab roots in dead_roots. */
2937			if (btrfs_root_refs(&gang[i]->root_item) == 0) {
2938				gang[i] = NULL;
2939				continue;
2940			}
2941			/* Grab all the search result for later use. */
2942			gang[i] = btrfs_grab_root(gang[i]);
2943		}
2944		spin_unlock(&fs_info->fs_roots_radix_lock);
2945
2946		for (i = 0; i < ret; i++) {
2947			if (!gang[i])
2948				continue;
2949			root_objectid = gang[i]->root_key.objectid;
2950			err = btrfs_orphan_cleanup(gang[i]);
2951			if (err)
2952				goto out;
2953			btrfs_put_root(gang[i]);
2954		}
2955		root_objectid++;
2956	}
2957out:
2958	/* Release the uncleaned roots due to error. */
2959	for (; i < ret; i++) {
2960		if (gang[i])
2961			btrfs_put_root(gang[i]);
2962	}
2963	return err;
2964}
2965
2966/*
2967 * Mounting logic specific to read-write file systems. Shared by open_ctree
2968 * and btrfs_remount when remounting from read-only to read-write.
2969 */
2970int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info)
2971{
2972	int ret;
2973	const bool cache_opt = btrfs_test_opt(fs_info, SPACE_CACHE);
2974	bool rebuild_free_space_tree = false;
2975
2976	if (btrfs_test_opt(fs_info, CLEAR_CACHE) &&
2977	    btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
2978		if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
2979			btrfs_warn(fs_info,
2980				   "'clear_cache' option is ignored with extent tree v2");
2981		else
2982			rebuild_free_space_tree = true;
2983	} else if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
2984		   !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID)) {
2985		btrfs_warn(fs_info, "free space tree is invalid");
2986		rebuild_free_space_tree = true;
2987	}
2988
2989	if (rebuild_free_space_tree) {
2990		btrfs_info(fs_info, "rebuilding free space tree");
2991		ret = btrfs_rebuild_free_space_tree(fs_info);
2992		if (ret) {
2993			btrfs_warn(fs_info,
2994				   "failed to rebuild free space tree: %d", ret);
2995			goto out;
2996		}
2997	}
2998
2999	if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
3000	    !btrfs_test_opt(fs_info, FREE_SPACE_TREE)) {
3001		btrfs_info(fs_info, "disabling free space tree");
3002		ret = btrfs_delete_free_space_tree(fs_info);
3003		if (ret) {
3004			btrfs_warn(fs_info,
3005				   "failed to disable free space tree: %d", ret);
3006			goto out;
3007		}
3008	}
3009
3010	/*
3011	 * btrfs_find_orphan_roots() is responsible for finding all the dead
3012	 * roots (with 0 refs), flag them with BTRFS_ROOT_DEAD_TREE and load
3013	 * them into the fs_info->fs_roots_radix tree. This must be done before
3014	 * calling btrfs_orphan_cleanup() on the tree root. If we don't do it
3015	 * first, then btrfs_orphan_cleanup() will delete a dead root's orphan
3016	 * item before the root's tree is deleted - this means that if we unmount
3017	 * or crash before the deletion completes, on the next mount we will not
3018	 * delete what remains of the tree because the orphan item does not
3019	 * exists anymore, which is what tells us we have a pending deletion.
3020	 */
3021	ret = btrfs_find_orphan_roots(fs_info);
3022	if (ret)
3023		goto out;
3024
3025	ret = btrfs_cleanup_fs_roots(fs_info);
3026	if (ret)
3027		goto out;
3028
3029	down_read(&fs_info->cleanup_work_sem);
3030	if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) ||
3031	    (ret = btrfs_orphan_cleanup(fs_info->tree_root))) {
3032		up_read(&fs_info->cleanup_work_sem);
3033		goto out;
3034	}
3035	up_read(&fs_info->cleanup_work_sem);
3036
3037	mutex_lock(&fs_info->cleaner_mutex);
3038	ret = btrfs_recover_relocation(fs_info);
3039	mutex_unlock(&fs_info->cleaner_mutex);
3040	if (ret < 0) {
3041		btrfs_warn(fs_info, "failed to recover relocation: %d", ret);
3042		goto out;
3043	}
3044
3045	if (btrfs_test_opt(fs_info, FREE_SPACE_TREE) &&
3046	    !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3047		btrfs_info(fs_info, "creating free space tree");
3048		ret = btrfs_create_free_space_tree(fs_info);
3049		if (ret) {
3050			btrfs_warn(fs_info,
3051				"failed to create free space tree: %d", ret);
3052			goto out;
3053		}
3054	}
3055
3056	if (cache_opt != btrfs_free_space_cache_v1_active(fs_info)) {
3057		ret = btrfs_set_free_space_cache_v1_active(fs_info, cache_opt);
3058		if (ret)
3059			goto out;
3060	}
3061
3062	ret = btrfs_resume_balance_async(fs_info);
3063	if (ret)
3064		goto out;
3065
3066	ret = btrfs_resume_dev_replace_async(fs_info);
3067	if (ret) {
3068		btrfs_warn(fs_info, "failed to resume dev_replace");
3069		goto out;
3070	}
3071
3072	btrfs_qgroup_rescan_resume(fs_info);
3073
3074	if (!fs_info->uuid_root) {
3075		btrfs_info(fs_info, "creating UUID tree");
3076		ret = btrfs_create_uuid_tree(fs_info);
3077		if (ret) {
3078			btrfs_warn(fs_info,
3079				   "failed to create the UUID tree %d", ret);
3080			goto out;
3081		}
3082	}
3083
3084out:
3085	return ret;
3086}
3087
3088/*
3089 * Do various sanity and dependency checks of different features.
3090 *
3091 * @is_rw_mount:	If the mount is read-write.
3092 *
3093 * This is the place for less strict checks (like for subpage or artificial
3094 * feature dependencies).
3095 *
3096 * For strict checks or possible corruption detection, see
3097 * btrfs_validate_super().
3098 *
3099 * This should be called after btrfs_parse_options(), as some mount options
3100 * (space cache related) can modify on-disk format like free space tree and
3101 * screw up certain feature dependencies.
3102 */
3103int btrfs_check_features(struct btrfs_fs_info *fs_info, bool is_rw_mount)
3104{
3105	struct btrfs_super_block *disk_super = fs_info->super_copy;
3106	u64 incompat = btrfs_super_incompat_flags(disk_super);
3107	const u64 compat_ro = btrfs_super_compat_ro_flags(disk_super);
3108	const u64 compat_ro_unsupp = (compat_ro & ~BTRFS_FEATURE_COMPAT_RO_SUPP);
3109
3110	if (incompat & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
3111		btrfs_err(fs_info,
3112		"cannot mount because of unknown incompat features (0x%llx)",
3113		    incompat);
3114		return -EINVAL;
3115	}
3116
3117	/* Runtime limitation for mixed block groups. */
3118	if ((incompat & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
3119	    (fs_info->sectorsize != fs_info->nodesize)) {
3120		btrfs_err(fs_info,
3121"unequal nodesize/sectorsize (%u != %u) are not allowed for mixed block groups",
3122			fs_info->nodesize, fs_info->sectorsize);
3123		return -EINVAL;
3124	}
3125
3126	/* Mixed backref is an always-enabled feature. */
3127	incompat |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
3128
3129	/* Set compression related flags just in case. */
3130	if (fs_info->compress_type == BTRFS_COMPRESS_LZO)
3131		incompat |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
3132	else if (fs_info->compress_type == BTRFS_COMPRESS_ZSTD)
3133		incompat |= BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD;
3134
3135	/*
3136	 * An ancient flag, which should really be marked deprecated.
3137	 * Such runtime limitation doesn't really need a incompat flag.
3138	 */
3139	if (btrfs_super_nodesize(disk_super) > PAGE_SIZE)
3140		incompat |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
3141
3142	if (compat_ro_unsupp && is_rw_mount) {
3143		btrfs_err(fs_info,
3144	"cannot mount read-write because of unknown compat_ro features (0x%llx)",
3145		       compat_ro);
3146		return -EINVAL;
3147	}
3148
3149	/*
3150	 * We have unsupported RO compat features, although RO mounted, we
3151	 * should not cause any metadata writes, including log replay.
3152	 * Or we could screw up whatever the new feature requires.
3153	 */
3154	if (compat_ro_unsupp && btrfs_super_log_root(disk_super) &&
3155	    !btrfs_test_opt(fs_info, NOLOGREPLAY)) {
3156		btrfs_err(fs_info,
3157"cannot replay dirty log with unsupported compat_ro features (0x%llx), try rescue=nologreplay",
3158			  compat_ro);
3159		return -EINVAL;
3160	}
3161
3162	/*
3163	 * Artificial limitations for block group tree, to force
3164	 * block-group-tree to rely on no-holes and free-space-tree.
3165	 */
3166	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE) &&
3167	    (!btrfs_fs_incompat(fs_info, NO_HOLES) ||
3168	     !btrfs_test_opt(fs_info, FREE_SPACE_TREE))) {
3169		btrfs_err(fs_info,
3170"block-group-tree feature requires no-holes and free-space-tree features");
3171		return -EINVAL;
3172	}
3173
3174	/*
3175	 * Subpage runtime limitation on v1 cache.
3176	 *
3177	 * V1 space cache still has some hard codeed PAGE_SIZE usage, while
3178	 * we're already defaulting to v2 cache, no need to bother v1 as it's
3179	 * going to be deprecated anyway.
3180	 */
3181	if (fs_info->sectorsize < PAGE_SIZE && btrfs_test_opt(fs_info, SPACE_CACHE)) {
3182		btrfs_warn(fs_info,
3183	"v1 space cache is not supported for page size %lu with sectorsize %u",
3184			   PAGE_SIZE, fs_info->sectorsize);
3185		return -EINVAL;
3186	}
3187
3188	/* This can be called by remount, we need to protect the super block. */
3189	spin_lock(&fs_info->super_lock);
3190	btrfs_set_super_incompat_flags(disk_super, incompat);
3191	spin_unlock(&fs_info->super_lock);
3192
3193	return 0;
3194}
3195
3196int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_devices,
3197		      char *options)
3198{
3199	u32 sectorsize;
3200	u32 nodesize;
3201	u32 stripesize;
3202	u64 generation;
3203	u16 csum_type;
3204	struct btrfs_super_block *disk_super;
3205	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
3206	struct btrfs_root *tree_root;
3207	struct btrfs_root *chunk_root;
3208	int ret;
3209	int level;
3210
3211	ret = init_mount_fs_info(fs_info, sb);
3212	if (ret)
3213		goto fail;
3214
3215	/* These need to be init'ed before we start creating inodes and such. */
3216	tree_root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID,
3217				     GFP_KERNEL);
3218	fs_info->tree_root = tree_root;
3219	chunk_root = btrfs_alloc_root(fs_info, BTRFS_CHUNK_TREE_OBJECTID,
3220				      GFP_KERNEL);
3221	fs_info->chunk_root = chunk_root;
3222	if (!tree_root || !chunk_root) {
3223		ret = -ENOMEM;
3224		goto fail;
3225	}
3226
3227	ret = btrfs_init_btree_inode(sb);
3228	if (ret)
3229		goto fail;
3230
3231	invalidate_bdev(fs_devices->latest_dev->bdev);
 
3232
3233	/*
3234	 * Read super block and check the signature bytes only
3235	 */
3236	disk_super = btrfs_read_dev_super(fs_devices->latest_dev->bdev);
3237	if (IS_ERR(disk_super)) {
3238		ret = PTR_ERR(disk_super);
3239		goto fail_alloc;
3240	}
3241
3242	btrfs_info(fs_info, "first mount of filesystem %pU", disk_super->fsid);
3243	/*
3244	 * Verify the type first, if that or the checksum value are
3245	 * corrupted, we'll find out
3246	 */
3247	csum_type = btrfs_super_csum_type(disk_super);
3248	if (!btrfs_supported_super_csum(csum_type)) {
3249		btrfs_err(fs_info, "unsupported checksum algorithm: %u",
3250			  csum_type);
3251		ret = -EINVAL;
3252		btrfs_release_disk_super(disk_super);
3253		goto fail_alloc;
3254	}
3255
3256	fs_info->csum_size = btrfs_super_csum_size(disk_super);
3257
3258	ret = btrfs_init_csum_hash(fs_info, csum_type);
3259	if (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, disk_super)) {
3269		btrfs_err(fs_info, "superblock checksum mismatch");
3270		ret = -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	memcpy(fs_info->super_for_commit, fs_info->super_copy,
3286	       sizeof(*fs_info->super_for_commit));
3287
3288	ret = btrfs_validate_mount_super(fs_info);
3289	if (ret) {
3290		btrfs_err(fs_info, "superblock contains fatal errors");
3291		ret = -EINVAL;
3292		goto fail_alloc;
3293	}
3294
3295	if (!btrfs_super_root(disk_super)) {
3296		btrfs_err(fs_info, "invalid superblock tree root bytenr");
3297		ret = -EINVAL;
3298		goto fail_alloc;
3299	}
3300
3301	/* check FS state, whether FS is broken. */
3302	if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
3303		WRITE_ONCE(fs_info->fs_error, -EUCLEAN);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3304
3305	/* Set up fs_info before parsing mount options */
3306	nodesize = btrfs_super_nodesize(disk_super);
 
3307	sectorsize = btrfs_super_sectorsize(disk_super);
3308	stripesize = sectorsize;
3309	fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids));
3310	fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
3311
3312	fs_info->nodesize = nodesize;
3313	fs_info->sectorsize = sectorsize;
3314	fs_info->sectorsize_bits = ilog2(sectorsize);
3315	fs_info->csums_per_leaf = BTRFS_MAX_ITEM_SIZE(fs_info) / fs_info->csum_size;
3316	fs_info->stripesize = stripesize;
3317
3318	/*
3319	 * Handle the space caching options appropriately now that we have the
3320	 * super block loaded and validated.
3321	 */
3322	btrfs_set_free_space_cache_settings(fs_info);
3323
3324	if (!btrfs_check_options(fs_info, &fs_info->mount_opt, sb->s_flags)) {
3325		ret = -EINVAL;
3326		goto fail_alloc;
3327	}
3328
3329	ret = btrfs_check_features(fs_info, !sb_rdonly(sb));
3330	if (ret < 0)
3331		goto fail_alloc;
3332
3333	/*
3334	 * At this point our mount options are validated, if we set ->max_inline
3335	 * to something non-standard make sure we truncate it to sectorsize.
3336	 */
3337	fs_info->max_inline = min_t(u64, fs_info->max_inline, fs_info->sectorsize);
3338
3339	if (sectorsize < PAGE_SIZE) {
3340		struct btrfs_subpage_info *subpage_info;
3341
3342		btrfs_warn(fs_info,
3343		"read-write for sector size %u with page size %lu is experimental",
3344			   sectorsize, PAGE_SIZE);
3345		subpage_info = kzalloc(sizeof(*subpage_info), GFP_KERNEL);
3346		if (!subpage_info) {
3347			ret = -ENOMEM;
3348			goto fail_alloc;
3349		}
3350		btrfs_init_subpage_info(subpage_info, sectorsize);
3351		fs_info->subpage_info = subpage_info;
3352	}
3353
3354	ret = btrfs_init_workqueues(fs_info);
3355	if (ret)
3356		goto fail_sb_buffer;
3357
3358	sb->s_bdi->ra_pages *= btrfs_super_num_devices(disk_super);
3359	sb->s_bdi->ra_pages = max(sb->s_bdi->ra_pages, SZ_4M / PAGE_SIZE);
3360
3361	/* Update the values for the current filesystem. */
3362	sb->s_blocksize = sectorsize;
3363	sb->s_blocksize_bits = blksize_bits(sectorsize);
3364	memcpy(&sb->s_uuid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE);
 
 
 
 
 
3365
3366	mutex_lock(&fs_info->chunk_mutex);
3367	ret = btrfs_read_sys_array(fs_info);
3368	mutex_unlock(&fs_info->chunk_mutex);
3369	if (ret) {
3370		btrfs_err(fs_info, "failed to read the system array: %d", ret);
 
3371		goto fail_sb_buffer;
3372	}
3373
 
 
3374	generation = btrfs_super_chunk_root_generation(disk_super);
3375	level = btrfs_super_chunk_root_level(disk_super);
3376	ret = load_super_root(chunk_root, btrfs_super_chunk_root(disk_super),
3377			      generation, level);
3378	if (ret) {
3379		btrfs_err(fs_info, "failed to read chunk root");
3380		goto fail_tree_roots;
 
 
 
 
 
 
3381	}
 
 
3382
3383	read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
3384			   offsetof(struct btrfs_header, chunk_tree_uuid),
3385			   BTRFS_UUID_SIZE);
3386
3387	ret = btrfs_read_chunk_tree(fs_info);
 
 
3388	if (ret) {
3389		btrfs_err(fs_info, "failed to read chunk tree: %d", ret);
3390		goto fail_tree_roots;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3391	}
 
 
3392
3393	/*
3394	 * At this point we know all the devices that make this filesystem,
3395	 * including the seed devices but we don't know yet if the replace
3396	 * target is required. So free devices that are not part of this
3397	 * filesystem but skip the replace target device which is checked
3398	 * below in btrfs_init_dev_replace().
3399	 */
3400	btrfs_free_extra_devids(fs_devices);
3401	if (!fs_devices->latest_dev->bdev) {
3402		btrfs_err(fs_info, "failed to read devices");
3403		ret = -EIO;
3404		goto fail_tree_roots;
3405	}
3406
3407	ret = init_tree_roots(fs_info);
 
3408	if (ret)
3409		goto fail_tree_roots;
 
3410
3411	/*
3412	 * Get zone type information of zoned block devices. This will also
3413	 * handle emulation of a zoned filesystem if a regular device has the
3414	 * zoned incompat feature flag set.
3415	 */
3416	ret = btrfs_get_dev_zone_info_all_devices(fs_info);
3417	if (ret) {
3418		btrfs_err(fs_info,
3419			  "zoned: failed to read device zone info: %d", ret);
3420		goto fail_block_groups;
3421	}
3422
3423	/*
3424	 * If we have a uuid root and we're not being told to rescan we need to
3425	 * check the generation here so we can set the
3426	 * BTRFS_FS_UPDATE_UUID_TREE_GEN bit.  Otherwise we could commit the
3427	 * transaction during a balance or the log replay without updating the
3428	 * uuid generation, and then if we crash we would rescan the uuid tree,
3429	 * even though it was perfectly fine.
3430	 */
3431	if (fs_info->uuid_root && !btrfs_test_opt(fs_info, RESCAN_UUID_TREE) &&
3432	    fs_info->generation == btrfs_super_uuid_tree_generation(disk_super))
3433		set_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags);
3434
3435	ret = btrfs_verify_dev_extents(fs_info);
3436	if (ret) {
3437		btrfs_err(fs_info,
3438			  "failed to verify dev extents against chunks: %d",
3439			  ret);
3440		goto fail_block_groups;
3441	}
3442	ret = btrfs_recover_balance(fs_info);
3443	if (ret) {
3444		btrfs_err(fs_info, "failed to recover balance: %d", ret);
3445		goto fail_block_groups;
3446	}
3447
3448	ret = btrfs_init_dev_stats(fs_info);
3449	if (ret) {
3450		btrfs_err(fs_info, "failed to init dev_stats: %d", ret);
3451		goto fail_block_groups;
3452	}
3453
3454	ret = btrfs_init_dev_replace(fs_info);
3455	if (ret) {
3456		btrfs_err(fs_info, "failed to init dev_replace: %d", ret);
3457		goto fail_block_groups;
3458	}
3459
3460	ret = btrfs_check_zoned_mode(fs_info);
3461	if (ret) {
3462		btrfs_err(fs_info, "failed to initialize zoned mode: %d",
3463			  ret);
3464		goto fail_block_groups;
3465	}
3466
3467	ret = btrfs_sysfs_add_fsid(fs_devices);
3468	if (ret) {
3469		btrfs_err(fs_info, "failed to init sysfs fsid interface: %d",
3470				ret);
3471		goto fail_block_groups;
3472	}
3473
3474	ret = btrfs_sysfs_add_mounted(fs_info);
3475	if (ret) {
3476		btrfs_err(fs_info, "failed to init sysfs interface: %d", ret);
3477		goto fail_fsdev_sysfs;
3478	}
3479
3480	ret = btrfs_init_space_info(fs_info);
3481	if (ret) {
3482		btrfs_err(fs_info, "failed to initialize space info: %d", ret);
3483		goto fail_sysfs;
 
 
3484	}
3485
3486	ret = btrfs_read_block_groups(fs_info);
3487	if (ret) {
3488		btrfs_err(fs_info, "failed to read block groups: %d", ret);
3489		goto fail_sysfs;
3490	}
3491
3492	btrfs_free_zone_cache(fs_info);
 
 
 
 
 
 
 
 
3493
3494	btrfs_check_active_zone_reservation(fs_info);
 
 
 
 
3495
3496	if (!sb_rdonly(sb) && fs_info->fs_devices->missing_devices &&
3497	    !btrfs_check_rw_degradable(fs_info, NULL)) {
3498		btrfs_warn(fs_info,
3499		"writable mount is not allowed due to too many missing devices");
3500		ret = -EINVAL;
3501		goto fail_sysfs;
3502	}
3503
3504	fs_info->cleaner_kthread = kthread_run(cleaner_kthread, fs_info,
3505					       "btrfs-cleaner");
3506	if (IS_ERR(fs_info->cleaner_kthread)) {
3507		ret = PTR_ERR(fs_info->cleaner_kthread);
3508		goto fail_sysfs;
3509	}
3510
3511	fs_info->transaction_kthread = kthread_run(transaction_kthread,
3512						   tree_root,
3513						   "btrfs-transaction");
3514	if (IS_ERR(fs_info->transaction_kthread)) {
3515		ret = PTR_ERR(fs_info->transaction_kthread);
3516		goto fail_cleaner;
3517	}
3518
3519	ret = btrfs_read_qgroup_config(fs_info);
3520	if (ret)
3521		goto fail_trans_kthread;
3522
3523	if (btrfs_build_ref_tree(fs_info))
3524		btrfs_err(fs_info, "couldn't build ref tree");
 
3525
3526	/* do not make disk changes in broken FS or nologreplay is given */
3527	if (btrfs_super_log_root(disk_super) != 0 &&
3528	    !btrfs_test_opt(fs_info, NOLOGREPLAY)) {
3529		btrfs_info(fs_info, "start tree-log replay");
3530		ret = btrfs_replay_log(fs_info, fs_devices);
3531		if (ret)
3532			goto fail_qgroup;
3533	}
3534
3535	fs_info->fs_root = btrfs_get_fs_root(fs_info, BTRFS_FS_TREE_OBJECTID, true);
3536	if (IS_ERR(fs_info->fs_root)) {
3537		ret = PTR_ERR(fs_info->fs_root);
3538		btrfs_warn(fs_info, "failed to read fs tree: %d", ret);
3539		fs_info->fs_root = NULL;
3540		goto fail_qgroup;
3541	}
3542
3543	if (sb_rdonly(sb))
3544		return 0;
 
3545
3546	ret = btrfs_start_pre_rw_mount(fs_info);
3547	if (ret) {
3548		close_ctree(fs_info);
3549		return ret;
 
 
3550	}
3551	btrfs_discard_resume(fs_info);
3552
3553	if (fs_info->uuid_root &&
3554	    (btrfs_test_opt(fs_info, RESCAN_UUID_TREE) ||
3555	     fs_info->generation != btrfs_super_uuid_tree_generation(disk_super))) {
3556		btrfs_info(fs_info, "checking UUID tree");
3557		ret = btrfs_check_uuid_tree(fs_info);
3558		if (ret) {
3559			btrfs_warn(fs_info,
3560				"failed to check the UUID tree: %d", ret);
3561			close_ctree(fs_info);
3562			return ret;
3563		}
3564	}
3565
3566	set_bit(BTRFS_FS_OPEN, &fs_info->flags);
3567
3568	/* Kick the cleaner thread so it'll start deleting snapshots. */
3569	if (test_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags))
3570		wake_up_process(fs_info->cleaner_kthread);
3571
3572	return 0;
3573
3574fail_qgroup:
3575	btrfs_free_qgroup_config(fs_info);
3576fail_trans_kthread:
3577	kthread_stop(fs_info->transaction_kthread);
3578	btrfs_cleanup_transaction(fs_info);
3579	btrfs_free_fs_roots(fs_info);
3580fail_cleaner:
3581	kthread_stop(fs_info->cleaner_kthread);
3582
3583	/*
3584	 * make sure we're done with the btree inode before we stop our
3585	 * kthreads
3586	 */
3587	filemap_write_and_wait(fs_info->btree_inode->i_mapping);
3588
3589fail_sysfs:
3590	btrfs_sysfs_remove_mounted(fs_info);
3591
3592fail_fsdev_sysfs:
3593	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
3594
3595fail_block_groups:
3596	btrfs_put_block_group_cache(fs_info);
3597
3598fail_tree_roots:
3599	if (fs_info->data_reloc_root)
3600		btrfs_drop_and_free_fs_root(fs_info, fs_info->data_reloc_root);
3601	free_root_pointers(fs_info, true);
3602	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
3603
3604fail_sb_buffer:
3605	btrfs_stop_all_workers(fs_info);
3606	btrfs_free_block_groups(fs_info);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3607fail_alloc:
3608	btrfs_mapping_tree_free(fs_info);
3609
 
3610	iput(fs_info->btree_inode);
3611fail:
3612	btrfs_close_devices(fs_info->fs_devices);
3613	ASSERT(ret < 0);
3614	return ret;
3615}
3616ALLOW_ERROR_INJECTION(open_ctree, ERRNO);
3617
3618static void btrfs_end_super_write(struct bio *bio)
3619{
3620	struct btrfs_device *device = bio->bi_private;
3621	struct bio_vec *bvec;
3622	struct bvec_iter_all iter_all;
3623	struct page *page;
3624
3625	bio_for_each_segment_all(bvec, bio, iter_all) {
3626		page = bvec->bv_page;
3627
3628		if (bio->bi_status) {
3629			btrfs_warn_rl_in_rcu(device->fs_info,
3630				"lost page write due to IO error on %s (%d)",
3631				btrfs_dev_name(device),
3632				blk_status_to_errno(bio->bi_status));
3633			ClearPageUptodate(page);
3634			SetPageError(page);
3635			btrfs_dev_stat_inc_and_print(device,
3636						     BTRFS_DEV_STAT_WRITE_ERRS);
3637		} else {
3638			SetPageUptodate(page);
3639		}
3640
3641		put_page(page);
3642		unlock_page(page);
3643	}
3644
3645	bio_put(bio);
3646}
3647
3648struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
3649						   int copy_num, bool drop_cache)
3650{
3651	struct btrfs_super_block *super;
3652	struct page *page;
3653	u64 bytenr, bytenr_orig;
3654	struct address_space *mapping = bdev->bd_inode->i_mapping;
3655	int ret;
3656
3657	bytenr_orig = btrfs_sb_offset(copy_num);
3658	ret = btrfs_sb_log_location_bdev(bdev, copy_num, READ, &bytenr);
3659	if (ret == -ENOENT)
3660		return ERR_PTR(-EINVAL);
3661	else if (ret)
3662		return ERR_PTR(ret);
3663
3664	if (bytenr + BTRFS_SUPER_INFO_SIZE >= bdev_nr_bytes(bdev))
3665		return ERR_PTR(-EINVAL);
3666
3667	if (drop_cache) {
3668		/* This should only be called with the primary sb. */
3669		ASSERT(copy_num == 0);
3670
3671		/*
3672		 * Drop the page of the primary superblock, so later read will
3673		 * always read from the device.
3674		 */
3675		invalidate_inode_pages2_range(mapping,
3676				bytenr >> PAGE_SHIFT,
3677				(bytenr + BTRFS_SUPER_INFO_SIZE) >> PAGE_SHIFT);
3678	}
3679
3680	page = read_cache_page_gfp(mapping, bytenr >> PAGE_SHIFT, GFP_NOFS);
3681	if (IS_ERR(page))
3682		return ERR_CAST(page);
3683
3684	super = page_address(page);
3685	if (btrfs_super_magic(super) != BTRFS_MAGIC) {
3686		btrfs_release_disk_super(super);
3687		return ERR_PTR(-ENODATA);
3688	}
3689
3690	if (btrfs_super_bytenr(super) != bytenr_orig) {
3691		btrfs_release_disk_super(super);
3692		return ERR_PTR(-EINVAL);
3693	}
3694
3695	return super;
3696}
3697
3698
3699struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev)
3700{
3701	struct btrfs_super_block *super, *latest = NULL;
 
 
3702	int i;
3703	u64 transid = 0;
 
3704
3705	/* we would like to check all the supers, but that would make
3706	 * a btrfs mount succeed after a mkfs from a different FS.
3707	 * So, we need to add a special mount option to scan for
3708	 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
3709	 */
3710	for (i = 0; i < 1; i++) {
3711		super = btrfs_read_dev_one_super(bdev, i, false);
3712		if (IS_ERR(super))
 
 
 
3713			continue;
3714
3715		if (!latest || btrfs_super_generation(super) > transid) {
3716			if (latest)
3717				btrfs_release_disk_super(super);
 
 
 
 
3718
3719			latest = super;
 
 
3720			transid = btrfs_super_generation(super);
 
 
3721		}
3722	}
3723
3724	return super;
3725}
3726
3727/*
3728 * Write superblock @sb to the @device. Do not wait for completion, all the
3729 * pages we use for writing are locked.
 
3730 *
3731 * Write @max_mirrors copies of the superblock, where 0 means default that fit
3732 * the expected device size at commit time. Note that max_mirrors must be
3733 * same for write and wait phases.
3734 *
3735 * Return number of errors when page is not found or submission fails.
3736 */
3737static int write_dev_supers(struct btrfs_device *device,
3738			    struct btrfs_super_block *sb, int max_mirrors)
 
3739{
3740	struct btrfs_fs_info *fs_info = device->fs_info;
3741	struct address_space *mapping = device->bdev->bd_inode->i_mapping;
3742	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
3743	int i;
3744	int errors = 0;
3745	int ret;
3746	u64 bytenr, bytenr_orig;
3747
3748	if (max_mirrors == 0)
3749		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
3750
3751	shash->tfm = fs_info->csum_shash;
3752
3753	for (i = 0; i < max_mirrors; i++) {
3754		struct page *page;
3755		struct bio *bio;
3756		struct btrfs_super_block *disk_super;
3757
3758		bytenr_orig = btrfs_sb_offset(i);
3759		ret = btrfs_sb_log_location(device, i, WRITE, &bytenr);
3760		if (ret == -ENOENT) {
3761			continue;
3762		} else if (ret < 0) {
3763			btrfs_err(device->fs_info,
3764				"couldn't get super block location for mirror %d",
3765				i);
3766			errors++;
3767			continue;
3768		}
3769		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
3770		    device->commit_total_bytes)
3771			break;
3772
3773		btrfs_set_super_bytenr(sb, bytenr_orig);
3774
3775		crypto_shash_digest(shash, (const char *)sb + BTRFS_CSUM_SIZE,
3776				    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE,
3777				    sb->csum);
3778
3779		page = find_or_create_page(mapping, bytenr >> PAGE_SHIFT,
3780					   GFP_NOFS);
3781		if (!page) {
3782			btrfs_err(device->fs_info,
3783			    "couldn't get super block page for bytenr %llu",
3784			    bytenr);
3785			errors++;
3786			continue;
3787		}
3788
3789		/* Bump the refcount for wait_dev_supers() */
3790		get_page(page);
3791
3792		disk_super = page_address(page);
3793		memcpy(disk_super, sb, BTRFS_SUPER_INFO_SIZE);
3794
3795		/*
3796		 * Directly use bios here instead of relying on the page cache
3797		 * to do I/O, so we don't lose the ability to do integrity
3798		 * checking.
3799		 */
3800		bio = bio_alloc(device->bdev, 1,
3801				REQ_OP_WRITE | REQ_SYNC | REQ_META | REQ_PRIO,
3802				GFP_NOFS);
3803		bio->bi_iter.bi_sector = bytenr >> SECTOR_SHIFT;
3804		bio->bi_private = device;
3805		bio->bi_end_io = btrfs_end_super_write;
3806		__bio_add_page(bio, page, BTRFS_SUPER_INFO_SIZE,
3807			       offset_in_page(bytenr));
3808
3809		/*
3810		 * We FUA only the first super block.  The others we allow to
3811		 * go down lazy and there's a short window where the on-disk
3812		 * copies might still contain the older version.
3813		 */
3814		if (i == 0 && !btrfs_test_opt(device->fs_info, NOBARRIER))
3815			bio->bi_opf |= REQ_FUA;
3816		submit_bio(bio);
3817
3818		if (btrfs_advance_sb_log(device, i))
3819			errors++;
3820	}
3821	return errors < i ? 0 : -1;
3822}
3823
3824/*
3825 * Wait for write completion of superblocks done by write_dev_supers,
3826 * @max_mirrors same for write and wait phases.
3827 *
3828 * Return number of errors when page is not found or not marked up to
3829 * date.
3830 */
3831static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
3832{
3833	int i;
3834	int errors = 0;
3835	bool primary_failed = false;
3836	int ret;
3837	u64 bytenr;
 
3838
3839	if (max_mirrors == 0)
3840		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
3841
3842	for (i = 0; i < max_mirrors; i++) {
3843		struct page *page;
3844
3845		ret = btrfs_sb_log_location(device, i, READ, &bytenr);
3846		if (ret == -ENOENT) {
3847			break;
3848		} else if (ret < 0) {
3849			errors++;
3850			if (i == 0)
3851				primary_failed = true;
3852			continue;
3853		}
3854		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
3855		    device->commit_total_bytes)
3856			break;
3857
3858		page = find_get_page(device->bdev->bd_inode->i_mapping,
3859				     bytenr >> PAGE_SHIFT);
3860		if (!page) {
3861			errors++;
3862			if (i == 0)
3863				primary_failed = true;
3864			continue;
3865		}
3866		/* Page is submitted locked and unlocked once the IO completes */
3867		wait_on_page_locked(page);
3868		if (PageError(page)) {
3869			errors++;
3870			if (i == 0)
3871				primary_failed = true;
3872		}
3873
3874		/* Drop our reference */
3875		put_page(page);
3876
3877		/* Drop the reference from the writing run */
3878		put_page(page);
3879	}
3880
3881	/* log error, force error return */
3882	if (primary_failed) {
3883		btrfs_err(device->fs_info, "error writing primary super block to device %llu",
3884			  device->devid);
3885		return -1;
3886	}
3887
3888	return errors < i ? 0 : -1;
3889}
3890
3891/*
3892 * endio for the write_dev_flush, this will wake anyone waiting
3893 * for the barrier when it is done
3894 */
3895static void btrfs_end_empty_barrier(struct bio *bio)
3896{
3897	bio_uninit(bio);
3898	complete(bio->bi_private);
3899}
3900
3901/*
3902 * Submit a flush request to the device if it supports it. Error handling is
3903 * done in the waiting counterpart.
3904 */
3905static void write_dev_flush(struct btrfs_device *device)
3906{
3907	struct bio *bio = &device->flush_bio;
3908
3909	device->last_flush_error = BLK_STS_OK;
3910
3911	bio_init(bio, device->bdev, NULL, 0,
3912		 REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH);
3913	bio->bi_end_io = btrfs_end_empty_barrier;
3914	init_completion(&device->flush_wait);
3915	bio->bi_private = &device->flush_wait;
3916	submit_bio(bio);
3917	set_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
3918}
3919
3920/*
3921 * If the flush bio has been submitted by write_dev_flush, wait for it.
3922 * Return true for any error, and false otherwise.
3923 */
3924static bool wait_dev_flush(struct btrfs_device *device)
3925{
3926	struct bio *bio = &device->flush_bio;
3927
3928	if (!test_and_clear_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state))
3929		return false;
3930
3931	wait_for_completion_io(&device->flush_wait);
3932
3933	if (bio->bi_status) {
3934		device->last_flush_error = bio->bi_status;
3935		btrfs_dev_stat_inc_and_print(device, BTRFS_DEV_STAT_FLUSH_ERRS);
3936		return true;
3937	}
3938
3939	return false;
3940}
3941
3942/*
3943 * send an empty flush down to each device in parallel,
3944 * then wait for them
3945 */
3946static int barrier_all_devices(struct btrfs_fs_info *info)
3947{
3948	struct list_head *head;
3949	struct btrfs_device *dev;
3950	int errors_wait = 0;
3951
3952	lockdep_assert_held(&info->fs_devices->device_list_mutex);
3953	/* send down all the barriers */
3954	head = &info->fs_devices->devices;
3955	list_for_each_entry(dev, head, dev_list) {
3956		if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
3957			continue;
3958		if (!dev->bdev)
3959			continue;
3960		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3961		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
3962			continue;
3963
3964		write_dev_flush(dev);
3965	}
3966
3967	/* wait for all the barriers */
3968	list_for_each_entry(dev, head, dev_list) {
3969		if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
3970			continue;
3971		if (!dev->bdev) {
3972			errors_wait++;
3973			continue;
3974		}
3975		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3976		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
3977			continue;
 
 
3978
3979		if (wait_dev_flush(dev))
3980			errors_wait++;
3981	}
3982
3983	/*
3984	 * Checks last_flush_error of disks in order to determine the device
3985	 * state.
3986	 */
3987	if (errors_wait && !btrfs_check_rw_degradable(info, NULL))
3988		return -EIO;
3989
3990	return 0;
3991}
 
 
 
 
 
3992
3993int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags)
3994{
3995	int raid_type;
3996	int min_tolerated = INT_MAX;
3997
3998	if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 ||
3999	    (flags & BTRFS_AVAIL_ALLOC_BIT_SINGLE))
4000		min_tolerated = min_t(int, min_tolerated,
4001				    btrfs_raid_array[BTRFS_RAID_SINGLE].
4002				    tolerated_failures);
4003
4004	for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
4005		if (raid_type == BTRFS_RAID_SINGLE)
4006			continue;
4007		if (!(flags & btrfs_raid_array[raid_type].bg_flag))
4008			continue;
4009		min_tolerated = min_t(int, min_tolerated,
4010				    btrfs_raid_array[raid_type].
4011				    tolerated_failures);
4012	}
4013
4014	if (min_tolerated == INT_MAX) {
4015		pr_warn("BTRFS: unknown raid flag: %llu", flags);
4016		min_tolerated = 0;
4017	}
4018
4019	return min_tolerated;
4020}
4021
4022int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors)
4023{
4024	struct list_head *head;
4025	struct btrfs_device *dev;
4026	struct btrfs_super_block *sb;
4027	struct btrfs_dev_item *dev_item;
4028	int ret;
4029	int do_barriers;
4030	int max_errors;
4031	int total_errors = 0;
4032	u64 flags;
4033
4034	do_barriers = !btrfs_test_opt(fs_info, NOBARRIER);
 
4035
4036	/*
4037	 * max_mirrors == 0 indicates we're from commit_transaction,
4038	 * not from fsync where the tree roots in fs_info have not
4039	 * been consistent on disk.
4040	 */
4041	if (max_mirrors == 0)
4042		backup_super_roots(fs_info);
4043
4044	sb = fs_info->super_for_commit;
4045	dev_item = &sb->dev_item;
4046
4047	mutex_lock(&fs_info->fs_devices->device_list_mutex);
4048	head = &fs_info->fs_devices->devices;
4049	max_errors = btrfs_super_num_devices(fs_info->super_copy) - 1;
4050
4051	if (do_barriers) {
4052		ret = barrier_all_devices(fs_info);
4053		if (ret) {
4054			mutex_unlock(
4055				&fs_info->fs_devices->device_list_mutex);
4056			btrfs_handle_fs_error(fs_info, ret,
4057					      "errors while submitting device barriers.");
4058			return ret;
4059		}
4060	}
4061
4062	list_for_each_entry(dev, head, dev_list) {
4063		if (!dev->bdev) {
4064			total_errors++;
4065			continue;
4066		}
4067		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4068		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4069			continue;
4070
4071		btrfs_set_stack_device_generation(dev_item, 0);
4072		btrfs_set_stack_device_type(dev_item, dev->type);
4073		btrfs_set_stack_device_id(dev_item, dev->devid);
4074		btrfs_set_stack_device_total_bytes(dev_item,
4075						   dev->commit_total_bytes);
4076		btrfs_set_stack_device_bytes_used(dev_item,
4077						  dev->commit_bytes_used);
4078		btrfs_set_stack_device_io_align(dev_item, dev->io_align);
4079		btrfs_set_stack_device_io_width(dev_item, dev->io_width);
4080		btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
4081		memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
4082		memcpy(dev_item->fsid, dev->fs_devices->metadata_uuid,
4083		       BTRFS_FSID_SIZE);
4084
4085		flags = btrfs_super_flags(sb);
4086		btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
4087
4088		ret = btrfs_validate_write_super(fs_info, sb);
4089		if (ret < 0) {
4090			mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4091			btrfs_handle_fs_error(fs_info, -EUCLEAN,
4092				"unexpected superblock corruption detected");
4093			return -EUCLEAN;
4094		}
4095
4096		ret = write_dev_supers(dev, sb, max_mirrors);
4097		if (ret)
4098			total_errors++;
4099	}
4100	if (total_errors > max_errors) {
4101		btrfs_err(fs_info, "%d errors while writing supers",
4102			  total_errors);
4103		mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4104
4105		/* FUA is masked off if unsupported and can't be the reason */
4106		btrfs_handle_fs_error(fs_info, -EIO,
4107				      "%d errors while writing supers",
4108				      total_errors);
4109		return -EIO;
4110	}
4111
4112	total_errors = 0;
4113	list_for_each_entry(dev, head, dev_list) {
4114		if (!dev->bdev)
4115			continue;
4116		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4117		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4118			continue;
4119
4120		ret = wait_dev_supers(dev, max_mirrors);
4121		if (ret)
4122			total_errors++;
4123	}
4124	mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4125	if (total_errors > max_errors) {
4126		btrfs_handle_fs_error(fs_info, -EIO,
4127				      "%d errors while writing supers",
4128				      total_errors);
4129		return -EIO;
4130	}
4131	return 0;
4132}
4133
4134/* Drop a fs root from the radix tree and free it. */
4135void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
4136				  struct btrfs_root *root)
4137{
4138	bool drop_ref = false;
4139
 
 
 
 
 
 
4140	spin_lock(&fs_info->fs_roots_radix_lock);
4141	radix_tree_delete(&fs_info->fs_roots_radix,
4142			  (unsigned long)root->root_key.objectid);
4143	if (test_and_clear_bit(BTRFS_ROOT_IN_RADIX, &root->state))
4144		drop_ref = true;
4145	spin_unlock(&fs_info->fs_roots_radix_lock);
4146
4147	if (BTRFS_FS_ERROR(fs_info)) {
4148		ASSERT(root->log_root == NULL);
4149		if (root->reloc_root) {
4150			btrfs_put_root(root->reloc_root);
4151			root->reloc_root = NULL;
4152		}
4153	}
4154
4155	if (drop_ref)
4156		btrfs_put_root(root);
 
 
4157}
4158
4159int btrfs_commit_super(struct btrfs_fs_info *fs_info)
4160{
4161	struct btrfs_root *root = fs_info->tree_root;
4162	struct btrfs_trans_handle *trans;
 
 
 
 
 
 
 
 
 
4163
4164	mutex_lock(&fs_info->cleaner_mutex);
4165	btrfs_run_delayed_iputs(fs_info);
4166	mutex_unlock(&fs_info->cleaner_mutex);
4167	wake_up_process(fs_info->cleaner_kthread);
 
4168
4169	/* wait until ongoing cleanup work done */
4170	down_write(&fs_info->cleanup_work_sem);
4171	up_write(&fs_info->cleanup_work_sem);
 
4172
4173	trans = btrfs_join_transaction(root);
4174	if (IS_ERR(trans))
4175		return PTR_ERR(trans);
4176	return btrfs_commit_transaction(trans);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4177}
4178
4179static void warn_about_uncommitted_trans(struct btrfs_fs_info *fs_info)
4180{
4181	struct btrfs_transaction *trans;
4182	struct btrfs_transaction *tmp;
4183	bool found = false;
4184
4185	if (list_empty(&fs_info->trans_list))
4186		return;
4187
4188	/*
4189	 * This function is only called at the very end of close_ctree(),
4190	 * thus no other running transaction, no need to take trans_lock.
4191	 */
4192	ASSERT(test_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags));
4193	list_for_each_entry_safe(trans, tmp, &fs_info->trans_list, list) {
4194		struct extent_state *cached = NULL;
4195		u64 dirty_bytes = 0;
4196		u64 cur = 0;
4197		u64 found_start;
4198		u64 found_end;
4199
4200		found = true;
4201		while (find_first_extent_bit(&trans->dirty_pages, cur,
4202			&found_start, &found_end, EXTENT_DIRTY, &cached)) {
4203			dirty_bytes += found_end + 1 - found_start;
4204			cur = found_end + 1;
4205		}
4206		btrfs_warn(fs_info,
4207	"transaction %llu (with %llu dirty metadata bytes) is not committed",
4208			   trans->transid, dirty_bytes);
4209		btrfs_cleanup_one_transaction(trans, fs_info);
4210
4211		if (trans == fs_info->running_transaction)
4212			fs_info->running_transaction = NULL;
4213		list_del_init(&trans->list);
4214
4215		btrfs_put_transaction(trans);
4216		trace_btrfs_transaction_commit(fs_info);
 
 
 
 
4217	}
4218	ASSERT(!found);
4219}
4220
4221void __cold close_ctree(struct btrfs_fs_info *fs_info)
4222{
 
4223	int ret;
4224
4225	set_bit(BTRFS_FS_CLOSING_START, &fs_info->flags);
 
 
 
4226
4227	/*
4228	 * If we had UNFINISHED_DROPS we could still be processing them, so
4229	 * clear that bit and wake up relocation so it can stop.
4230	 * We must do this before stopping the block group reclaim task, because
4231	 * at btrfs_relocate_block_group() we wait for this bit, and after the
4232	 * wait we stop with -EINTR if btrfs_fs_closing() returns non-zero - we
4233	 * have just set BTRFS_FS_CLOSING_START, so btrfs_fs_closing() will
4234	 * return 1.
4235	 */
4236	btrfs_wake_unfinished_drop(fs_info);
4237
4238	/*
4239	 * We may have the reclaim task running and relocating a data block group,
4240	 * in which case it may create delayed iputs. So stop it before we park
4241	 * the cleaner kthread otherwise we can get new delayed iputs after
4242	 * parking the cleaner, and that can make the async reclaim task to hang
4243	 * if it's waiting for delayed iputs to complete, since the cleaner is
4244	 * parked and can not run delayed iputs - this will make us hang when
4245	 * trying to stop the async reclaim task.
4246	 */
4247	cancel_work_sync(&fs_info->reclaim_bgs_work);
4248	/*
4249	 * We don't want the cleaner to start new transactions, add more delayed
4250	 * iputs, etc. while we're closing. We can't use kthread_stop() yet
4251	 * because that frees the task_struct, and the transaction kthread might
4252	 * still try to wake up the cleaner.
4253	 */
4254	kthread_park(fs_info->cleaner_kthread);
4255
4256	/* wait for the qgroup rescan worker to stop */
4257	btrfs_qgroup_wait_for_completion(fs_info, false);
 
 
 
 
 
 
 
 
 
 
4258
4259	/* wait for the uuid_scan task to finish */
4260	down(&fs_info->uuid_tree_rescan_sem);
4261	/* avoid complains from lockdep et al., set sem back to initial state */
4262	up(&fs_info->uuid_tree_rescan_sem);
4263
4264	/* pause restriper - we want to resume on mount */
4265	btrfs_pause_balance(fs_info);
 
 
4266
4267	btrfs_dev_replace_suspend_for_unmount(fs_info);
 
4268
4269	btrfs_scrub_cancel(fs_info);
4270
4271	/* wait for any defraggers to finish */
4272	wait_event(fs_info->transaction_wait,
4273		   (atomic_read(&fs_info->defrag_running) == 0));
4274
4275	/* clear out the rbtree of defraggable inodes */
4276	btrfs_cleanup_defrag_inodes(fs_info);
 
 
4277
4278	/*
4279	 * After we parked the cleaner kthread, ordered extents may have
4280	 * completed and created new delayed iputs. If one of the async reclaim
4281	 * tasks is running and in the RUN_DELAYED_IPUTS flush state, then we
4282	 * can hang forever trying to stop it, because if a delayed iput is
4283	 * added after it ran btrfs_run_delayed_iputs() and before it called
4284	 * btrfs_wait_on_delayed_iputs(), it will hang forever since there is
4285	 * no one else to run iputs.
4286	 *
4287	 * So wait for all ongoing ordered extents to complete and then run
4288	 * delayed iputs. This works because once we reach this point no one
4289	 * can either create new ordered extents nor create delayed iputs
4290	 * through some other means.
4291	 *
4292	 * Also note that btrfs_wait_ordered_roots() is not safe here, because
4293	 * it waits for BTRFS_ORDERED_COMPLETE to be set on an ordered extent,
4294	 * but the delayed iput for the respective inode is made only when doing
4295	 * the final btrfs_put_ordered_extent() (which must happen at
4296	 * btrfs_finish_ordered_io() when we are unmounting).
4297	 */
4298	btrfs_flush_workqueue(fs_info->endio_write_workers);
4299	/* Ordered extents for free space inodes. */
4300	btrfs_flush_workqueue(fs_info->endio_freespace_worker);
4301	btrfs_run_delayed_iputs(fs_info);
4302
4303	cancel_work_sync(&fs_info->async_reclaim_work);
4304	cancel_work_sync(&fs_info->async_data_reclaim_work);
4305	cancel_work_sync(&fs_info->preempt_reclaim_work);
4306
4307	/* Cancel or finish ongoing discard work */
4308	btrfs_discard_cleanup(fs_info);
4309
4310	if (!sb_rdonly(fs_info->sb)) {
4311		/*
4312		 * The cleaner kthread is stopped, so do one final pass over
4313		 * unused block groups.
4314		 */
4315		btrfs_delete_unused_bgs(fs_info);
4316
4317		/*
4318		 * There might be existing delayed inode workers still running
4319		 * and holding an empty delayed inode item. We must wait for
4320		 * them to complete first because they can create a transaction.
4321		 * This happens when someone calls btrfs_balance_delayed_items()
4322		 * and then a transaction commit runs the same delayed nodes
4323		 * before any delayed worker has done something with the nodes.
4324		 * We must wait for any worker here and not at transaction
4325		 * commit time since that could cause a deadlock.
4326		 * This is a very rare case.
4327		 */
4328		btrfs_flush_workqueue(fs_info->delayed_workers);
4329
4330		ret = btrfs_commit_super(fs_info);
4331		if (ret)
4332			btrfs_err(fs_info, "commit super ret %d", ret);
4333	}
4334
4335	if (BTRFS_FS_ERROR(fs_info))
4336		btrfs_error_commit_super(fs_info);
 
 
 
4337
4338	kthread_stop(fs_info->transaction_kthread);
4339	kthread_stop(fs_info->cleaner_kthread);
4340
4341	ASSERT(list_empty(&fs_info->delayed_iputs));
4342	set_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags);
4343
4344	if (btrfs_check_quota_leak(fs_info)) {
4345		WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
4346		btrfs_err(fs_info, "qgroup reserved space leaked");
 
 
 
 
4347	}
4348
4349	btrfs_free_qgroup_config(fs_info);
4350	ASSERT(list_empty(&fs_info->delalloc_roots));
 
 
 
 
 
 
 
 
4351
4352	if (percpu_counter_sum(&fs_info->delalloc_bytes)) {
4353		btrfs_info(fs_info, "at unmount delalloc count %lld",
4354		       percpu_counter_sum(&fs_info->delalloc_bytes));
4355	}
4356
4357	if (percpu_counter_sum(&fs_info->ordered_bytes))
4358		btrfs_info(fs_info, "at unmount dio bytes count %lld",
4359			   percpu_counter_sum(&fs_info->ordered_bytes));
4360
4361	btrfs_sysfs_remove_mounted(fs_info);
4362	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
4363
4364	btrfs_put_block_group_cache(fs_info);
 
 
 
 
 
 
 
 
 
 
 
4365
4366	/*
4367	 * we must make sure there is not any read request to
4368	 * submit after we stopping all workers.
4369	 */
4370	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
4371	btrfs_stop_all_workers(fs_info);
4372
4373	/* We shouldn't have any transaction open at this point */
4374	warn_about_uncommitted_trans(fs_info);
4375
4376	clear_bit(BTRFS_FS_OPEN, &fs_info->flags);
4377	free_root_pointers(fs_info, true);
4378	btrfs_free_fs_roots(fs_info);
 
 
 
4379
4380	/*
4381	 * We must free the block groups after dropping the fs_roots as we could
4382	 * have had an IO error and have left over tree log blocks that aren't
4383	 * cleaned up until the fs roots are freed.  This makes the block group
4384	 * accounting appear to be wrong because there's pending reserved bytes,
4385	 * so make sure we do the block group cleanup afterwards.
4386	 */
4387	btrfs_free_block_groups(fs_info);
4388
4389	iput(fs_info->btree_inode);
 
 
 
4390
4391	btrfs_mapping_tree_free(fs_info);
4392	btrfs_close_devices(fs_info->fs_devices);
 
 
 
 
 
 
 
 
 
 
 
 
 
4393}
4394
4395void btrfs_mark_buffer_dirty(struct btrfs_trans_handle *trans,
4396			     struct extent_buffer *buf)
4397{
4398	struct btrfs_fs_info *fs_info = buf->fs_info;
4399	u64 transid = btrfs_header_generation(buf);
 
 
4400
4401#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4402	/*
4403	 * This is a fast path so only do this check if we have sanity tests
4404	 * enabled.  Normal people shouldn't be using unmapped buffers as dirty
4405	 * outside of the sanity tests.
4406	 */
4407	if (unlikely(test_bit(EXTENT_BUFFER_UNMAPPED, &buf->bflags)))
 
 
 
4408		return;
4409#endif
4410	/* This is an active transaction (its state < TRANS_STATE_UNBLOCKED). */
4411	ASSERT(trans->transid == fs_info->generation);
4412	btrfs_assert_tree_write_locked(buf);
4413	if (unlikely(transid != fs_info->generation)) {
4414		btrfs_abort_transaction(trans, -EUCLEAN);
4415		btrfs_crit(fs_info,
4416"dirty buffer transid mismatch, logical %llu found transid %llu running transid %llu",
4417			   buf->start, transid, fs_info->generation);
4418	}
4419	set_extent_buffer_dirty(buf);
4420}
4421
4422static void __btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info,
4423					int flush_delayed)
4424{
4425	/*
4426	 * looks as though older kernels can get into trouble with
4427	 * this code, they end up stuck in balance_dirty_pages forever
4428	 */
4429	int ret;
 
4430
4431	if (current->flags & PF_MEMALLOC)
4432		return;
4433
4434	if (flush_delayed)
4435		btrfs_balance_delayed_items(fs_info);
4436
4437	ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
4438				     BTRFS_DIRTY_METADATA_THRESH,
4439				     fs_info->dirty_metadata_batch);
4440	if (ret > 0) {
4441		balance_dirty_pages_ratelimited(fs_info->btree_inode->i_mapping);
4442	}
 
4443}
4444
4445void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info)
4446{
4447	__btrfs_btree_balance_dirty(fs_info, 1);
 
 
 
 
 
4448}
4449
4450void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info)
4451{
4452	__btrfs_btree_balance_dirty(fs_info, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4453}
4454
4455static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info)
4456{
 
 
 
 
 
 
 
 
 
4457	/* cleanup FS via transaction */
4458	btrfs_cleanup_transaction(fs_info);
4459
4460	mutex_lock(&fs_info->cleaner_mutex);
4461	btrfs_run_delayed_iputs(fs_info);
4462	mutex_unlock(&fs_info->cleaner_mutex);
4463
4464	down_write(&fs_info->cleanup_work_sem);
4465	up_write(&fs_info->cleanup_work_sem);
4466}
4467
4468static void btrfs_drop_all_logs(struct btrfs_fs_info *fs_info)
4469{
4470	struct btrfs_root *gang[8];
4471	u64 root_objectid = 0;
4472	int ret;
4473
4474	spin_lock(&fs_info->fs_roots_radix_lock);
4475	while ((ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
4476					     (void **)gang, root_objectid,
4477					     ARRAY_SIZE(gang))) != 0) {
4478		int i;
4479
4480		for (i = 0; i < ret; i++)
4481			gang[i] = btrfs_grab_root(gang[i]);
4482		spin_unlock(&fs_info->fs_roots_radix_lock);
4483
4484		for (i = 0; i < ret; i++) {
4485			if (!gang[i])
4486				continue;
4487			root_objectid = gang[i]->root_key.objectid;
4488			btrfs_free_log(NULL, gang[i]);
4489			btrfs_put_root(gang[i]);
4490		}
4491		root_objectid++;
4492		spin_lock(&fs_info->fs_roots_radix_lock);
4493	}
4494	spin_unlock(&fs_info->fs_roots_radix_lock);
4495	btrfs_free_log_root_tree(NULL, fs_info);
 
 
 
4496}
4497
4498static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
4499{
 
4500	struct btrfs_ordered_extent *ordered;
 
4501
4502	spin_lock(&root->ordered_extent_lock);
4503	/*
4504	 * This will just short circuit the ordered completion stuff which will
4505	 * make sure the ordered extent gets properly cleaned up.
4506	 */
4507	list_for_each_entry(ordered, &root->ordered_extents,
4508			    root_extent_list)
4509		set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
4510	spin_unlock(&root->ordered_extent_lock);
4511}
4512
4513static void btrfs_destroy_all_ordered_extents(struct btrfs_fs_info *fs_info)
4514{
4515	struct btrfs_root *root;
4516	LIST_HEAD(splice);
4517
4518	spin_lock(&fs_info->ordered_root_lock);
4519	list_splice_init(&fs_info->ordered_roots, &splice);
4520	while (!list_empty(&splice)) {
4521		root = list_first_entry(&splice, struct btrfs_root,
4522					ordered_root);
4523		list_move_tail(&root->ordered_root,
4524			       &fs_info->ordered_roots);
4525
4526		spin_unlock(&fs_info->ordered_root_lock);
4527		btrfs_destroy_ordered_extents(root);
4528
4529		cond_resched();
4530		spin_lock(&fs_info->ordered_root_lock);
 
 
 
 
 
 
 
 
 
4531	}
4532	spin_unlock(&fs_info->ordered_root_lock);
4533
4534	/*
4535	 * We need this here because if we've been flipped read-only we won't
4536	 * get sync() from the umount, so we need to make sure any ordered
4537	 * extents that haven't had their dirty pages IO start writeout yet
4538	 * actually get run and error out properly.
4539	 */
4540	btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
4541}
4542
4543static void btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
4544				       struct btrfs_fs_info *fs_info)
4545{
4546	struct rb_node *node;
4547	struct btrfs_delayed_ref_root *delayed_refs;
4548	struct btrfs_delayed_ref_node *ref;
 
4549
4550	delayed_refs = &trans->delayed_refs;
4551
4552	spin_lock(&delayed_refs->lock);
4553	if (atomic_read(&delayed_refs->num_entries) == 0) {
4554		spin_unlock(&delayed_refs->lock);
4555		btrfs_debug(fs_info, "delayed_refs has NO entry");
4556		return;
4557	}
4558
4559	while ((node = rb_first_cached(&delayed_refs->href_root)) != NULL) {
4560		struct btrfs_delayed_ref_head *head;
4561		struct rb_node *n;
4562		bool pin_bytes = false;
4563
4564		head = rb_entry(node, struct btrfs_delayed_ref_head,
4565				href_node);
4566		if (btrfs_delayed_ref_lock(delayed_refs, head))
4567			continue;
4568
4569		spin_lock(&head->lock);
4570		while ((n = rb_first_cached(&head->ref_tree)) != NULL) {
4571			ref = rb_entry(n, struct btrfs_delayed_ref_node,
4572				       ref_node);
4573			rb_erase_cached(&ref->ref_node, &head->ref_tree);
4574			RB_CLEAR_NODE(&ref->ref_node);
4575			if (!list_empty(&ref->add_list))
4576				list_del(&ref->add_list);
4577			atomic_dec(&delayed_refs->num_entries);
4578			btrfs_put_delayed_ref(ref);
4579			btrfs_delayed_refs_rsv_release(fs_info, 1, 0);
4580		}
4581		if (head->must_insert_reserved)
4582			pin_bytes = true;
4583		btrfs_free_delayed_extent_op(head->extent_op);
4584		btrfs_delete_ref_head(delayed_refs, head);
4585		spin_unlock(&head->lock);
4586		spin_unlock(&delayed_refs->lock);
4587		mutex_unlock(&head->mutex);
4588
4589		if (pin_bytes) {
4590			struct btrfs_block_group *cache;
4591
4592			cache = btrfs_lookup_block_group(fs_info, head->bytenr);
4593			BUG_ON(!cache);
4594
4595			spin_lock(&cache->space_info->lock);
4596			spin_lock(&cache->lock);
4597			cache->pinned += head->num_bytes;
4598			btrfs_space_info_update_bytes_pinned(fs_info,
4599				cache->space_info, head->num_bytes);
4600			cache->reserved -= head->num_bytes;
4601			cache->space_info->bytes_reserved -= head->num_bytes;
4602			spin_unlock(&cache->lock);
4603			spin_unlock(&cache->space_info->lock);
4604
4605			btrfs_put_block_group(cache);
4606
4607			btrfs_error_unpin_extent_range(fs_info, head->bytenr,
4608				head->bytenr + head->num_bytes - 1);
4609		}
4610		btrfs_cleanup_ref_head_accounting(fs_info, delayed_refs, head);
4611		btrfs_put_delayed_ref_head(head);
4612		cond_resched();
4613		spin_lock(&delayed_refs->lock);
4614	}
4615	btrfs_qgroup_destroy_extent_records(trans);
4616
4617	spin_unlock(&delayed_refs->lock);
 
 
4618}
4619
4620static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
4621{
4622	struct btrfs_inode *btrfs_inode;
4623	LIST_HEAD(splice);
4624
4625	spin_lock(&root->delalloc_lock);
4626	list_splice_init(&root->delalloc_inodes, &splice);
 
4627
4628	while (!list_empty(&splice)) {
4629		struct inode *inode = NULL;
4630		btrfs_inode = list_first_entry(&splice, struct btrfs_inode,
4631					       delalloc_inodes);
4632		btrfs_del_delalloc_inode(btrfs_inode);
4633		spin_unlock(&root->delalloc_lock);
4634
4635		/*
4636		 * Make sure we get a live inode and that it'll not disappear
4637		 * meanwhile.
4638		 */
4639		inode = igrab(&btrfs_inode->vfs_inode);
4640		if (inode) {
4641			unsigned int nofs_flag;
4642
4643			nofs_flag = memalloc_nofs_save();
4644			invalidate_inode_pages2(inode->i_mapping);
4645			memalloc_nofs_restore(nofs_flag);
4646			iput(inode);
4647		}
4648		spin_lock(&root->delalloc_lock);
4649	}
4650	spin_unlock(&root->delalloc_lock);
 
4651}
4652
4653static void btrfs_destroy_all_delalloc_inodes(struct btrfs_fs_info *fs_info)
4654{
4655	struct btrfs_root *root;
4656	LIST_HEAD(splice);
 
 
 
 
 
4657
4658	spin_lock(&fs_info->delalloc_root_lock);
4659	list_splice_init(&fs_info->delalloc_roots, &splice);
4660	while (!list_empty(&splice)) {
4661		root = list_first_entry(&splice, struct btrfs_root,
4662					 delalloc_root);
4663		root = btrfs_grab_root(root);
4664		BUG_ON(!root);
4665		spin_unlock(&fs_info->delalloc_root_lock);
4666
4667		btrfs_destroy_delalloc_inodes(root);
4668		btrfs_put_root(root);
4669
4670		spin_lock(&fs_info->delalloc_root_lock);
4671	}
4672	spin_unlock(&fs_info->delalloc_root_lock);
 
 
 
4673}
4674
4675static void btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
4676					 struct extent_io_tree *dirty_pages,
4677					 int mark)
4678{
 
 
 
4679	struct extent_buffer *eb;
4680	u64 start = 0;
4681	u64 end;
 
 
4682
4683	while (find_first_extent_bit(dirty_pages, start, &start, &end,
4684				     mark, NULL)) {
4685		clear_extent_bits(dirty_pages, start, end, mark);
 
 
 
 
4686		while (start <= end) {
4687			eb = find_extent_buffer(fs_info, start);
4688			start += fs_info->nodesize;
4689			if (!eb)
 
4690				continue;
 
4691
4692			btrfs_tree_lock(eb);
4693			wait_on_extent_buffer_writeback(eb);
4694			btrfs_clear_buffer_dirty(NULL, eb);
4695			btrfs_tree_unlock(eb);
 
 
 
 
 
 
 
 
4696
4697			free_extent_buffer_stale(eb);
 
 
 
 
 
 
 
 
 
 
 
4698		}
4699	}
 
 
4700}
4701
4702static void btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
4703					struct extent_io_tree *unpin)
4704{
 
4705	u64 start;
4706	u64 end;
 
4707
 
4708	while (1) {
4709		struct extent_state *cached_state = NULL;
4710
4711		/*
4712		 * The btrfs_finish_extent_commit() may get the same range as
4713		 * ours between find_first_extent_bit and clear_extent_dirty.
4714		 * Hence, hold the unused_bg_unpin_mutex to avoid double unpin
4715		 * the same extent range.
4716		 */
4717		mutex_lock(&fs_info->unused_bg_unpin_mutex);
4718		if (!find_first_extent_bit(unpin, 0, &start, &end,
4719					   EXTENT_DIRTY, &cached_state)) {
4720			mutex_unlock(&fs_info->unused_bg_unpin_mutex);
4721			break;
4722		}
4723
4724		clear_extent_dirty(unpin, start, end, &cached_state);
4725		free_extent_state(cached_state);
4726		btrfs_error_unpin_extent_range(fs_info, start, end);
4727		mutex_unlock(&fs_info->unused_bg_unpin_mutex);
 
 
 
 
4728		cond_resched();
4729	}
4730}
4731
4732static void btrfs_cleanup_bg_io(struct btrfs_block_group *cache)
4733{
4734	struct inode *inode;
4735
4736	inode = cache->io_ctl.inode;
4737	if (inode) {
4738		unsigned int nofs_flag;
4739
4740		nofs_flag = memalloc_nofs_save();
4741		invalidate_inode_pages2(inode->i_mapping);
4742		memalloc_nofs_restore(nofs_flag);
4743
4744		BTRFS_I(inode)->generation = 0;
4745		cache->io_ctl.inode = NULL;
4746		iput(inode);
4747	}
4748	ASSERT(cache->io_ctl.pages == NULL);
4749	btrfs_put_block_group(cache);
4750}
4751
4752void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *cur_trans,
4753			     struct btrfs_fs_info *fs_info)
4754{
4755	struct btrfs_block_group *cache;
4756
4757	spin_lock(&cur_trans->dirty_bgs_lock);
4758	while (!list_empty(&cur_trans->dirty_bgs)) {
4759		cache = list_first_entry(&cur_trans->dirty_bgs,
4760					 struct btrfs_block_group,
4761					 dirty_list);
4762
4763		if (!list_empty(&cache->io_list)) {
4764			spin_unlock(&cur_trans->dirty_bgs_lock);
4765			list_del_init(&cache->io_list);
4766			btrfs_cleanup_bg_io(cache);
4767			spin_lock(&cur_trans->dirty_bgs_lock);
4768		}
4769
4770		list_del_init(&cache->dirty_list);
4771		spin_lock(&cache->lock);
4772		cache->disk_cache_state = BTRFS_DC_ERROR;
4773		spin_unlock(&cache->lock);
4774
4775		spin_unlock(&cur_trans->dirty_bgs_lock);
4776		btrfs_put_block_group(cache);
4777		btrfs_dec_delayed_refs_rsv_bg_updates(fs_info);
4778		spin_lock(&cur_trans->dirty_bgs_lock);
4779	}
4780	spin_unlock(&cur_trans->dirty_bgs_lock);
4781
4782	/*
4783	 * Refer to the definition of io_bgs member for details why it's safe
4784	 * to use it without any locking
4785	 */
4786	while (!list_empty(&cur_trans->io_bgs)) {
4787		cache = list_first_entry(&cur_trans->io_bgs,
4788					 struct btrfs_block_group,
4789					 io_list);
4790
4791		list_del_init(&cache->io_list);
4792		spin_lock(&cache->lock);
4793		cache->disk_cache_state = BTRFS_DC_ERROR;
4794		spin_unlock(&cache->lock);
4795		btrfs_cleanup_bg_io(cache);
4796	}
4797}
4798
4799static void btrfs_free_all_qgroup_pertrans(struct btrfs_fs_info *fs_info)
4800{
4801	struct btrfs_root *gang[8];
4802	int i;
4803	int ret;
4804
4805	spin_lock(&fs_info->fs_roots_radix_lock);
4806	while (1) {
4807		ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix,
4808						 (void **)gang, 0,
4809						 ARRAY_SIZE(gang),
4810						 BTRFS_ROOT_TRANS_TAG);
4811		if (ret == 0)
4812			break;
4813		for (i = 0; i < ret; i++) {
4814			struct btrfs_root *root = gang[i];
4815
4816			btrfs_qgroup_free_meta_all_pertrans(root);
4817			radix_tree_tag_clear(&fs_info->fs_roots_radix,
4818					(unsigned long)root->root_key.objectid,
4819					BTRFS_ROOT_TRANS_TAG);
4820		}
4821	}
4822	spin_unlock(&fs_info->fs_roots_radix_lock);
4823}
4824
4825void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
4826				   struct btrfs_fs_info *fs_info)
4827{
4828	struct btrfs_device *dev, *tmp;
4829
4830	btrfs_cleanup_dirty_bgs(cur_trans, fs_info);
4831	ASSERT(list_empty(&cur_trans->dirty_bgs));
4832	ASSERT(list_empty(&cur_trans->io_bgs));
4833
4834	list_for_each_entry_safe(dev, tmp, &cur_trans->dev_update_list,
4835				 post_commit_list) {
4836		list_del_init(&dev->post_commit_list);
4837	}
4838
4839	btrfs_destroy_delayed_refs(cur_trans, fs_info);
4840
4841	cur_trans->state = TRANS_STATE_COMMIT_START;
4842	wake_up(&fs_info->transaction_blocked_wait);
4843
4844	cur_trans->state = TRANS_STATE_UNBLOCKED;
4845	wake_up(&fs_info->transaction_wait);
4846
4847	btrfs_destroy_delayed_inodes(fs_info);
4848
4849	btrfs_destroy_marked_extents(fs_info, &cur_trans->dirty_pages,
4850				     EXTENT_DIRTY);
4851	btrfs_destroy_pinned_extent(fs_info, &cur_trans->pinned_extents);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4852
4853	btrfs_free_all_qgroup_pertrans(fs_info);
4854
4855	cur_trans->state =TRANS_STATE_COMPLETED;
4856	wake_up(&cur_trans->commit_wait);
4857}
4858
4859static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info)
4860{
4861	struct btrfs_transaction *t;
4862
4863	mutex_lock(&fs_info->transaction_kthread_mutex);
 
4864
4865	spin_lock(&fs_info->trans_lock);
4866	while (!list_empty(&fs_info->trans_list)) {
4867		t = list_first_entry(&fs_info->trans_list,
4868				     struct btrfs_transaction, list);
4869		if (t->state >= TRANS_STATE_COMMIT_PREP) {
4870			refcount_inc(&t->use_count);
4871			spin_unlock(&fs_info->trans_lock);
4872			btrfs_wait_for_commit(fs_info, t->transid);
4873			btrfs_put_transaction(t);
4874			spin_lock(&fs_info->trans_lock);
4875			continue;
4876		}
4877		if (t == fs_info->running_transaction) {
4878			t->state = TRANS_STATE_COMMIT_DOING;
4879			spin_unlock(&fs_info->trans_lock);
4880			/*
4881			 * We wait for 0 num_writers since we don't hold a trans
4882			 * handle open currently for this transaction.
4883			 */
4884			wait_event(t->writer_wait,
4885				   atomic_read(&t->num_writers) == 0);
4886		} else {
4887			spin_unlock(&fs_info->trans_lock);
4888		}
4889		btrfs_cleanup_one_transaction(t, fs_info);
4890
4891		spin_lock(&fs_info->trans_lock);
4892		if (t == fs_info->running_transaction)
4893			fs_info->running_transaction = NULL;
4894		list_del_init(&t->list);
4895		spin_unlock(&fs_info->trans_lock);
 
 
4896
4897		btrfs_put_transaction(t);
4898		trace_btrfs_transaction_commit(fs_info);
4899		spin_lock(&fs_info->trans_lock);
4900	}
4901	spin_unlock(&fs_info->trans_lock);
4902	btrfs_destroy_all_ordered_extents(fs_info);
4903	btrfs_destroy_delayed_inodes(fs_info);
4904	btrfs_assert_delayed_root_empty(fs_info);
4905	btrfs_destroy_all_delalloc_inodes(fs_info);
4906	btrfs_drop_all_logs(fs_info);
4907	mutex_unlock(&fs_info->transaction_kthread_mutex);
4908
4909	return 0;
4910}
4911
4912int btrfs_init_root_free_objectid(struct btrfs_root *root)
4913{
4914	struct btrfs_path *path;
4915	int ret;
4916	struct extent_buffer *l;
4917	struct btrfs_key search_key;
4918	struct btrfs_key found_key;
4919	int slot;
4920
4921	path = btrfs_alloc_path();
4922	if (!path)
4923		return -ENOMEM;
4924
4925	search_key.objectid = BTRFS_LAST_FREE_OBJECTID;
4926	search_key.type = -1;
4927	search_key.offset = (u64)-1;
4928	ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
4929	if (ret < 0)
4930		goto error;
4931	if (ret == 0) {
4932		/*
4933		 * Key with offset -1 found, there would have to exist a root
4934		 * with such id, but this is out of valid range.
4935		 */
4936		ret = -EUCLEAN;
4937		goto error;
4938	}
4939	if (path->slots[0] > 0) {
4940		slot = path->slots[0] - 1;
4941		l = path->nodes[0];
4942		btrfs_item_key_to_cpu(l, &found_key, slot);
4943		root->free_objectid = max_t(u64, found_key.objectid + 1,
4944					    BTRFS_FIRST_FREE_OBJECTID);
4945	} else {
4946		root->free_objectid = BTRFS_FIRST_FREE_OBJECTID;
4947	}
4948	ret = 0;
4949error:
4950	btrfs_free_path(path);
4951	return ret;
4952}
4953
4954int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid)
4955{
4956	int ret;
4957	mutex_lock(&root->objectid_mutex);
4958
4959	if (unlikely(root->free_objectid >= BTRFS_LAST_FREE_OBJECTID)) {
4960		btrfs_warn(root->fs_info,
4961			   "the objectid of root %llu reaches its highest value",
4962			   root->root_key.objectid);
4963		ret = -ENOSPC;
4964		goto out;
4965	}
4966
4967	*objectid = root->free_objectid++;
4968	ret = 0;
4969out:
4970	mutex_unlock(&root->objectid_mutex);
4971	return ret;
4972}
v3.1
 
   1/*
   2 * Copyright (C) 2007 Oracle.  All rights reserved.
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of the GNU General Public
   6 * License v2 as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful,
   9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11 * General Public License for more details.
  12 *
  13 * You should have received a copy of the GNU General Public
  14 * License along with this program; if not, write to the
  15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16 * Boston, MA 021110-1307, USA.
  17 */
  18
  19#include <linux/fs.h>
  20#include <linux/blkdev.h>
  21#include <linux/scatterlist.h>
  22#include <linux/swap.h>
  23#include <linux/radix-tree.h>
  24#include <linux/writeback.h>
  25#include <linux/buffer_head.h>
  26#include <linux/workqueue.h>
  27#include <linux/kthread.h>
  28#include <linux/freezer.h>
  29#include <linux/crc32c.h>
  30#include <linux/slab.h>
  31#include <linux/migrate.h>
  32#include <linux/ratelimit.h>
 
 
 
 
 
  33#include <asm/unaligned.h>
  34#include "compat.h"
  35#include "ctree.h"
  36#include "disk-io.h"
  37#include "transaction.h"
  38#include "btrfs_inode.h"
  39#include "volumes.h"
  40#include "print-tree.h"
  41#include "async-thread.h"
  42#include "locking.h"
  43#include "tree-log.h"
  44#include "free-space-cache.h"
  45#include "inode-map.h"
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  46
  47static struct extent_io_ops btree_extent_io_ops;
  48static void end_workqueue_fn(struct btrfs_work *work);
  49static void free_fs_root(struct btrfs_root *root);
  50static void btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
  51				    int read_only);
  52static int btrfs_destroy_ordered_operations(struct btrfs_root *root);
  53static int btrfs_destroy_ordered_extents(struct btrfs_root *root);
  54static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
  55				      struct btrfs_root *root);
  56static int btrfs_destroy_pending_snapshots(struct btrfs_transaction *t);
  57static int btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
  58static int btrfs_destroy_marked_extents(struct btrfs_root *root,
  59					struct extent_io_tree *dirty_pages,
  60					int mark);
  61static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
  62				       struct extent_io_tree *pinned_extents);
  63static int btrfs_cleanup_transaction(struct btrfs_root *root);
  64
  65/*
  66 * end_io_wq structs are used to do processing in task context when an IO is
  67 * complete.  This is used during reads to verify checksums, and it is used
  68 * by writes to insert metadata for new file extents after IO is complete.
  69 */
  70struct end_io_wq {
  71	struct bio *bio;
  72	bio_end_io_t *end_io;
  73	void *private;
  74	struct btrfs_fs_info *info;
  75	int error;
  76	int metadata;
  77	struct list_head list;
  78	struct btrfs_work work;
  79};
  80
  81/*
  82 * async submit bios are used to offload expensive checksumming
  83 * onto the worker threads.  They checksum file and metadata bios
  84 * just before they are sent down the IO stack.
  85 */
  86struct async_submit_bio {
  87	struct inode *inode;
  88	struct bio *bio;
  89	struct list_head list;
  90	extent_submit_bio_hook_t *submit_bio_start;
  91	extent_submit_bio_hook_t *submit_bio_done;
  92	int rw;
  93	int mirror_num;
  94	unsigned long bio_flags;
  95	/*
  96	 * bio_offset is optional, can be used if the pages in the bio
  97	 * can't tell us where in the file the bio should go
  98	 */
  99	u64 bio_offset;
 100	struct btrfs_work work;
 101};
 102
 103/*
 104 * Lockdep class keys for extent_buffer->lock's in this root.  For a given
 105 * eb, the lockdep key is determined by the btrfs_root it belongs to and
 106 * the level the eb occupies in the tree.
 107 *
 108 * Different roots are used for different purposes and may nest inside each
 109 * other and they require separate keysets.  As lockdep keys should be
 110 * static, assign keysets according to the purpose of the root as indicated
 111 * by btrfs_root->objectid.  This ensures that all special purpose roots
 112 * have separate keysets.
 113 *
 114 * Lock-nesting across peer nodes is always done with the immediate parent
 115 * node locked thus preventing deadlock.  As lockdep doesn't know this, use
 116 * subclass to avoid triggering lockdep warning in such cases.
 117 *
 118 * The key is set by the readpage_end_io_hook after the buffer has passed
 119 * csum validation but before the pages are unlocked.  It is also set by
 120 * btrfs_init_new_buffer on freshly allocated blocks.
 121 *
 122 * We also add a check to make sure the highest level of the tree is the
 123 * same as our lockdep setup here.  If BTRFS_MAX_LEVEL changes, this code
 124 * needs update as well.
 125 */
 126#ifdef CONFIG_DEBUG_LOCK_ALLOC
 127# if BTRFS_MAX_LEVEL != 8
 128#  error
 129# endif
 130
 131static struct btrfs_lockdep_keyset {
 132	u64			id;		/* root objectid */
 133	const char		*name_stem;	/* lock name stem */
 134	char			names[BTRFS_MAX_LEVEL + 1][20];
 135	struct lock_class_key	keys[BTRFS_MAX_LEVEL + 1];
 136} btrfs_lockdep_keysets[] = {
 137	{ .id = BTRFS_ROOT_TREE_OBJECTID,	.name_stem = "root"	},
 138	{ .id = BTRFS_EXTENT_TREE_OBJECTID,	.name_stem = "extent"	},
 139	{ .id = BTRFS_CHUNK_TREE_OBJECTID,	.name_stem = "chunk"	},
 140	{ .id = BTRFS_DEV_TREE_OBJECTID,	.name_stem = "dev"	},
 141	{ .id = BTRFS_FS_TREE_OBJECTID,		.name_stem = "fs"	},
 142	{ .id = BTRFS_CSUM_TREE_OBJECTID,	.name_stem = "csum"	},
 143	{ .id = BTRFS_ORPHAN_OBJECTID,		.name_stem = "orphan"	},
 144	{ .id = BTRFS_TREE_LOG_OBJECTID,	.name_stem = "log"	},
 145	{ .id = BTRFS_TREE_RELOC_OBJECTID,	.name_stem = "treloc"	},
 146	{ .id = BTRFS_DATA_RELOC_TREE_OBJECTID,	.name_stem = "dreloc"	},
 147	{ .id = 0,				.name_stem = "tree"	},
 148};
 149
 150void __init btrfs_init_lockdep(void)
 151{
 152	int i, j;
 
 
 
 
 
 153
 154	/* initialize lockdep class names */
 155	for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) {
 156		struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i];
 157
 158		for (j = 0; j < ARRAY_SIZE(ks->names); j++)
 159			snprintf(ks->names[j], sizeof(ks->names[j]),
 160				 "btrfs-%s-%02d", ks->name_stem, j);
 
 
 
 
 
 
 161	}
 162}
 163
 164void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
 165				    int level)
 166{
 167	struct btrfs_lockdep_keyset *ks;
 168
 169	BUG_ON(level >= ARRAY_SIZE(ks->keys));
 170
 171	/* find the matching keyset, id 0 is the default entry */
 172	for (ks = btrfs_lockdep_keysets; ks->id; ks++)
 173		if (ks->id == objectid)
 174			break;
 175
 176	lockdep_set_class_and_name(&eb->lock,
 177				   &ks->keys[level], ks->names[level]);
 
 
 
 178}
 179
 180#endif
 181
 182/*
 183 * extents on the btree inode are pretty simple, there's one extent
 184 * that covers the entire device
 
 
 185 */
 186static struct extent_map *btree_get_extent(struct inode *inode,
 187		struct page *page, size_t pg_offset, u64 start, u64 len,
 188		int create)
 189{
 190	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 191	struct extent_map *em;
 192	int ret;
 193
 194	read_lock(&em_tree->lock);
 195	em = lookup_extent_mapping(em_tree, start, len);
 196	if (em) {
 197		em->bdev =
 198			BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
 199		read_unlock(&em_tree->lock);
 200		goto out;
 201	}
 202	read_unlock(&em_tree->lock);
 203
 204	em = alloc_extent_map();
 205	if (!em) {
 206		em = ERR_PTR(-ENOMEM);
 207		goto out;
 208	}
 209	em->start = 0;
 210	em->len = (u64)-1;
 211	em->block_len = (u64)-1;
 212	em->block_start = 0;
 213	em->bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
 214
 215	write_lock(&em_tree->lock);
 216	ret = add_extent_mapping(em_tree, em);
 217	if (ret == -EEXIST) {
 218		u64 failed_start = em->start;
 219		u64 failed_len = em->len;
 220
 221		free_extent_map(em);
 222		em = lookup_extent_mapping(em_tree, start, len);
 223		if (em) {
 224			ret = 0;
 225		} else {
 226			em = lookup_extent_mapping(em_tree, failed_start,
 227						   failed_len);
 228			ret = -EIO;
 229		}
 230	} else if (ret) {
 231		free_extent_map(em);
 232		em = NULL;
 233	}
 234	write_unlock(&em_tree->lock);
 235
 236	if (ret)
 237		em = ERR_PTR(ret);
 238out:
 239	return em;
 240}
 241
 242u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
 243{
 244	return crc32c(seed, data, len);
 
 
 
 
 
 
 
 245}
 246
 247void btrfs_csum_final(u32 crc, char *result)
 248{
 249	put_unaligned_le32(~crc, result);
 
 
 
 
 
 
 
 
 250}
 251
 252/*
 253 * compute the csum for a btree block, and either verify it or write it
 254 * into the csum field of the block.
 255 */
 256static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 257			   int verify)
 258{
 259	u16 csum_size =
 260		btrfs_super_csum_size(&root->fs_info->super_copy);
 261	char *result = NULL;
 262	unsigned long len;
 263	unsigned long cur_len;
 264	unsigned long offset = BTRFS_CSUM_SIZE;
 265	char *kaddr;
 266	unsigned long map_start;
 267	unsigned long map_len;
 268	int err;
 269	u32 crc = ~(u32)0;
 270	unsigned long inline_result;
 271
 272	len = buf->len - offset;
 273	while (len > 0) {
 274		err = map_private_extent_buffer(buf, offset, 32,
 275					&kaddr, &map_start, &map_len);
 276		if (err)
 277			return 1;
 278		cur_len = min(len, map_len - (offset - map_start));
 279		crc = btrfs_csum_data(root, kaddr + offset - map_start,
 280				      crc, cur_len);
 281		len -= cur_len;
 282		offset += cur_len;
 283	}
 284	if (csum_size > sizeof(inline_result)) {
 285		result = kzalloc(csum_size * sizeof(char), GFP_NOFS);
 286		if (!result)
 287			return 1;
 288	} else {
 289		result = (char *)&inline_result;
 290	}
 291
 292	btrfs_csum_final(crc, result);
 
 293
 294	if (verify) {
 295		if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
 296			u32 val;
 297			u32 found = 0;
 298			memcpy(&found, result, csum_size);
 299
 300			read_extent_buffer(buf, &val, 0, csum_size);
 301			printk_ratelimited(KERN_INFO "btrfs: %s checksum verify "
 302				       "failed on %llu wanted %X found %X "
 303				       "level %d\n",
 304				       root->fs_info->sb->s_id,
 305				       (unsigned long long)buf->start, val, found,
 306				       btrfs_header_level(buf));
 307			if (result != (char *)&inline_result)
 308				kfree(result);
 309			return 1;
 310		}
 311	} else {
 312		write_extent_buffer(buf, result, 0, csum_size);
 313	}
 314	if (result != (char *)&inline_result)
 315		kfree(result);
 316	return 0;
 317}
 318
 319/*
 320 * we can't consider a given block up to date unless the transid of the
 321 * block matches the transid in the parent node's pointer.  This is how we
 322 * detect blocks that either didn't get written at all or got written
 323 * in the wrong place.
 324 */
 325static int verify_parent_transid(struct extent_io_tree *io_tree,
 326				 struct extent_buffer *eb, u64 parent_transid)
 327{
 328	struct extent_state *cached_state = NULL;
 329	int ret;
 
 330
 331	if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 332		return 0;
 333
 334	lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
 335			 0, &cached_state, GFP_NOFS);
 336	if (extent_buffer_uptodate(io_tree, eb, cached_state) &&
 337	    btrfs_header_generation(eb) == parent_transid) {
 338		ret = 0;
 339		goto out;
 
 
 
 
 
 
 340	}
 341	printk_ratelimited("parent transid verify failed on %llu wanted %llu "
 342		       "found %llu\n",
 343		       (unsigned long long)eb->start,
 344		       (unsigned long long)parent_transid,
 345		       (unsigned long long)btrfs_header_generation(eb));
 346	ret = 1;
 347	clear_extent_buffer_uptodate(io_tree, eb, &cached_state);
 348out:
 349	unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
 350			     &cached_state, GFP_NOFS);
 351	return ret;
 352}
 353
 354/*
 355 * helper to read a given tree block, doing retries as required when
 356 * the checksums don't match and we have alternate mirrors to try.
 
 
 
 357 */
 358static int btree_read_extent_buffer_pages(struct btrfs_root *root,
 359					  struct extent_buffer *eb,
 360					  u64 start, u64 parent_transid)
 361{
 362	struct extent_io_tree *io_tree;
 
 363	int ret;
 364	int num_copies = 0;
 365	int mirror_num = 0;
 
 
 
 366
 367	clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 368	io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
 369	while (1) {
 370		ret = read_extent_buffer_pages(io_tree, eb, start, 1,
 371					       btree_get_extent, mirror_num);
 372		if (!ret &&
 373		    !verify_parent_transid(io_tree, eb, parent_transid))
 374			return ret;
 375
 376		/*
 377		 * This buffer's crc is fine, but its contents are corrupted, so
 378		 * there is no reason to read the other copies, they won't be
 379		 * any less wrong.
 380		 */
 381		if (test_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags))
 382			return ret;
 383
 384		num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
 385					      eb->start, eb->len);
 386		if (num_copies == 1)
 387			return ret;
 
 
 
 
 
 388
 389		mirror_num++;
 
 
 
 390		if (mirror_num > num_copies)
 391			return ret;
 392	}
 393	return -EIO;
 
 
 
 
 394}
 395
 396/*
 397 * checksum a dirty tree block before IO.  This has extra checks to make sure
 398 * we only fill in the checksum field in the first page of a multi-page block
 399 */
 400
 401static int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
 402{
 403	struct extent_io_tree *tree;
 404	u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
 405	u64 found_start;
 406	unsigned long len;
 407	struct extent_buffer *eb;
 408	int ret;
 409
 410	tree = &BTRFS_I(page->mapping->host)->io_tree;
 
 
 
 
 411
 412	if (page->private == EXTENT_PAGE_PRIVATE) {
 413		WARN_ON(1);
 414		goto out;
 415	}
 416	if (!page->private) {
 417		WARN_ON(1);
 418		goto out;
 419	}
 420	len = page->private >> 2;
 421	WARN_ON(len == 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 422
 423	eb = alloc_extent_buffer(tree, start, len, page);
 424	if (eb == NULL) {
 425		WARN_ON(1);
 426		goto out;
 427	}
 428	ret = btree_read_extent_buffer_pages(root, eb, start + PAGE_CACHE_SIZE,
 429					     btrfs_header_generation(eb));
 430	BUG_ON(ret);
 431	WARN_ON(!btrfs_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN));
 432
 433	found_start = btrfs_header_bytenr(eb);
 434	if (found_start != start) {
 435		WARN_ON(1);
 436		goto err;
 437	}
 438	if (eb->first_page != page) {
 439		WARN_ON(1);
 440		goto err;
 441	}
 442	if (!PageUptodate(page)) {
 443		WARN_ON(1);
 444		goto err;
 445	}
 446	csum_tree_block(root, eb, 0);
 447err:
 448	free_extent_buffer(eb);
 449out:
 450	return 0;
 
 
 
 
 
 
 
 
 
 
 451}
 452
 453static int check_tree_block_fsid(struct btrfs_root *root,
 454				 struct extent_buffer *eb)
 455{
 456	struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
 457	u8 fsid[BTRFS_UUID_SIZE];
 458	int ret = 1;
 459
 460	read_extent_buffer(eb, fsid, (unsigned long)btrfs_header_fsid(eb),
 461			   BTRFS_FSID_SIZE);
 462	while (fs_devices) {
 463		if (!memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE)) {
 464			ret = 0;
 465			break;
 466		}
 467		fs_devices = fs_devices->seed;
 468	}
 469	return ret;
 470}
 471
 472#define CORRUPT(reason, eb, root, slot)				\
 473	printk(KERN_CRIT "btrfs: corrupt leaf, %s: block=%llu,"	\
 474	       "root=%llu, slot=%d\n", reason,			\
 475	       (unsigned long long)btrfs_header_bytenr(eb),	\
 476	       (unsigned long long)root->objectid, slot)
 477
 478static noinline int check_leaf(struct btrfs_root *root,
 479			       struct extent_buffer *leaf)
 480{
 481	struct btrfs_key key;
 482	struct btrfs_key leaf_key;
 483	u32 nritems = btrfs_header_nritems(leaf);
 484	int slot;
 485
 486	if (nritems == 0)
 487		return 0;
 488
 489	/* Check the 0 item */
 490	if (btrfs_item_offset_nr(leaf, 0) + btrfs_item_size_nr(leaf, 0) !=
 491	    BTRFS_LEAF_DATA_SIZE(root)) {
 492		CORRUPT("invalid item offset size pair", leaf, root, 0);
 493		return -EIO;
 494	}
 495
 496	/*
 497	 * Check to make sure each items keys are in the correct order and their
 498	 * offsets make sense.  We only have to loop through nritems-1 because
 499	 * we check the current slot against the next slot, which verifies the
 500	 * next slot's offset+size makes sense and that the current's slot
 501	 * offset is correct.
 502	 */
 503	for (slot = 0; slot < nritems - 1; slot++) {
 504		btrfs_item_key_to_cpu(leaf, &leaf_key, slot);
 505		btrfs_item_key_to_cpu(leaf, &key, slot + 1);
 506
 507		/* Make sure the keys are in the right order */
 508		if (btrfs_comp_cpu_keys(&leaf_key, &key) >= 0) {
 509			CORRUPT("bad key order", leaf, root, slot);
 510			return -EIO;
 511		}
 512
 513		/*
 514		 * Make sure the offset and ends are right, remember that the
 515		 * item data starts at the end of the leaf and grows towards the
 516		 * front.
 517		 */
 518		if (btrfs_item_offset_nr(leaf, slot) !=
 519			btrfs_item_end_nr(leaf, slot + 1)) {
 520			CORRUPT("slot offset bad", leaf, root, slot);
 521			return -EIO;
 522		}
 523
 524		/*
 525		 * Check to make sure that we don't point outside of the leaf,
 526		 * just incase all the items are consistent to eachother, but
 527		 * all point outside of the leaf.
 528		 */
 529		if (btrfs_item_end_nr(leaf, slot) >
 530		    BTRFS_LEAF_DATA_SIZE(root)) {
 531			CORRUPT("slot end outside of leaf", leaf, root, slot);
 532			return -EIO;
 533		}
 534	}
 535
 536	return 0;
 537}
 538
 539static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
 540			       struct extent_state *state)
 
 541{
 542	struct extent_io_tree *tree;
 543	u64 found_start;
 544	int found_level;
 545	unsigned long len;
 546	struct extent_buffer *eb;
 547	struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 548	int ret = 0;
 549
 550	tree = &BTRFS_I(page->mapping->host)->io_tree;
 551	if (page->private == EXTENT_PAGE_PRIVATE)
 
 
 
 
 
 
 552		goto out;
 553	if (!page->private)
 
 
 
 
 554		goto out;
 555
 556	len = page->private >> 2;
 557	WARN_ON(len == 0);
 558
 559	eb = alloc_extent_buffer(tree, start, len, page);
 560	if (eb == NULL) {
 561		ret = -EIO;
 562		goto out;
 563	}
 564
 565	found_start = btrfs_header_bytenr(eb);
 566	if (found_start != start) {
 567		printk_ratelimited(KERN_INFO "btrfs bad tree block start "
 568			       "%llu %llu\n",
 569			       (unsigned long long)found_start,
 570			       (unsigned long long)eb->start);
 571		ret = -EIO;
 572		goto err;
 
 
 
 
 
 573	}
 574	if (eb->first_page != page) {
 575		printk(KERN_INFO "btrfs bad first page %lu %lu\n",
 576		       eb->first_page->index, page->index);
 577		WARN_ON(1);
 
 578		ret = -EIO;
 579		goto err;
 580	}
 581	if (check_tree_block_fsid(root, eb)) {
 582		printk_ratelimited(KERN_INFO "btrfs bad fsid on block %llu\n",
 583			       (unsigned long long)eb->start);
 
 
 
 584		ret = -EIO;
 585		goto err;
 586	}
 587	found_level = btrfs_header_level(eb);
 
 
 588
 589	btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb),
 590				       eb, found_level);
 591
 592	ret = csum_tree_block(root, eb, 1);
 593	if (ret) {
 594		ret = -EIO;
 595		goto err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 596	}
 597
 598	/*
 599	 * If this is a leaf block and it is corrupt, set the corrupt bit so
 600	 * that we don't try and read the other copies of this block, just
 601	 * return -EIO.
 602	 */
 603	if (found_level == 0 && check_leaf(root, eb)) {
 604		set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 605		ret = -EIO;
 606	}
 607
 608	end = min_t(u64, eb->len, PAGE_CACHE_SIZE);
 609	end = eb->start + end - 1;
 610err:
 611	free_extent_buffer(eb);
 
 
 
 612out:
 613	return ret;
 614}
 615
 616static void end_workqueue_bio(struct bio *bio, int err)
 
 
 617{
 618	struct end_io_wq *end_io_wq = bio->bi_private;
 619	struct btrfs_fs_info *fs_info;
 620
 621	fs_info = end_io_wq->info;
 622	end_io_wq->error = err;
 623	end_io_wq->work.func = end_workqueue_fn;
 624	end_io_wq->work.flags = 0;
 625
 626	if (bio->bi_rw & REQ_WRITE) {
 627		if (end_io_wq->metadata == 1)
 628			btrfs_queue_worker(&fs_info->endio_meta_write_workers,
 629					   &end_io_wq->work);
 630		else if (end_io_wq->metadata == 2)
 631			btrfs_queue_worker(&fs_info->endio_freespace_worker,
 632					   &end_io_wq->work);
 633		else
 634			btrfs_queue_worker(&fs_info->endio_write_workers,
 635					   &end_io_wq->work);
 636	} else {
 637		if (end_io_wq->metadata)
 638			btrfs_queue_worker(&fs_info->endio_meta_workers,
 639					   &end_io_wq->work);
 640		else
 641			btrfs_queue_worker(&fs_info->endio_workers,
 642					   &end_io_wq->work);
 643	}
 644}
 
 
 
 645
 646/*
 647 * For the metadata arg you want
 648 *
 649 * 0 - if data
 650 * 1 - if normal metadta
 651 * 2 - if writing to the free space cache area
 652 */
 653int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
 654			int metadata)
 655{
 656	struct end_io_wq *end_io_wq;
 657	end_io_wq = kmalloc(sizeof(*end_io_wq), GFP_NOFS);
 658	if (!end_io_wq)
 659		return -ENOMEM;
 660
 661	end_io_wq->private = bio->bi_private;
 662	end_io_wq->end_io = bio->bi_end_io;
 663	end_io_wq->info = info;
 664	end_io_wq->error = 0;
 665	end_io_wq->bio = bio;
 666	end_io_wq->metadata = metadata;
 667
 668	bio->bi_private = end_io_wq;
 669	bio->bi_end_io = end_workqueue_bio;
 670	return 0;
 671}
 672
 673unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info)
 674{
 675	unsigned long limit = min_t(unsigned long,
 676				    info->workers.max_workers,
 677				    info->fs_devices->open_devices);
 678	return 256 * limit;
 
 
 
 679}
 680
 681static void run_one_async_start(struct btrfs_work *work)
 682{
 683	struct async_submit_bio *async;
 
 684
 685	async = container_of(work, struct  async_submit_bio, work);
 686	async->submit_bio_start(async->inode, async->rw, async->bio,
 687			       async->mirror_num, async->bio_flags,
 688			       async->bio_offset);
 689}
 690
 691static void run_one_async_done(struct btrfs_work *work)
 
 692{
 693	struct btrfs_fs_info *fs_info;
 694	struct async_submit_bio *async;
 695	int limit;
 696
 697	async = container_of(work, struct  async_submit_bio, work);
 698	fs_info = BTRFS_I(async->inode)->root->fs_info;
 
 
 
 
 
 
 
 
 699
 700	limit = btrfs_async_submit_limit(fs_info);
 701	limit = limit * 2 / 3;
 
 
 
 
 
 
 
 
 702
 703	atomic_dec(&fs_info->nr_async_submits);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 704
 705	if (atomic_read(&fs_info->nr_async_submits) < limit &&
 706	    waitqueue_active(&fs_info->async_submit_wait))
 707		wake_up(&fs_info->async_submit_wait);
 
 
 
 708
 709	async->submit_bio_done(async->inode, async->rw, async->bio,
 710			       async->mirror_num, async->bio_flags,
 711			       async->bio_offset);
 712}
 
 
 
 713
 714static void run_one_async_free(struct btrfs_work *work)
 715{
 716	struct async_submit_bio *async;
 
 
 
 
 717
 718	async = container_of(work, struct  async_submit_bio, work);
 719	kfree(async);
 
 
 
 
 
 
 720}
 721
 722int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
 723			int rw, struct bio *bio, int mirror_num,
 724			unsigned long bio_flags,
 725			u64 bio_offset,
 726			extent_submit_bio_hook_t *submit_bio_start,
 727			extent_submit_bio_hook_t *submit_bio_done)
 
 
 
 728{
 729	struct async_submit_bio *async;
 
 
 
 730
 731	async = kmalloc(sizeof(*async), GFP_NOFS);
 732	if (!async)
 733		return -ENOMEM;
 
 734
 735	async->inode = inode;
 736	async->rw = rw;
 737	async->bio = bio;
 738	async->mirror_num = mirror_num;
 739	async->submit_bio_start = submit_bio_start;
 740	async->submit_bio_done = submit_bio_done;
 741
 742	async->work.func = run_one_async_start;
 743	async->work.ordered_func = run_one_async_done;
 744	async->work.ordered_free = run_one_async_free;
 745
 746	async->work.flags = 0;
 747	async->bio_flags = bio_flags;
 748	async->bio_offset = bio_offset;
 749
 750	atomic_inc(&fs_info->nr_async_submits);
 751
 752	if (rw & REQ_SYNC)
 753		btrfs_set_work_high_prio(&async->work);
 754
 755	btrfs_queue_worker(&fs_info->workers, &async->work);
 756
 757	while (atomic_read(&fs_info->async_submit_draining) &&
 758	      atomic_read(&fs_info->nr_async_submits)) {
 759		wait_event(fs_info->async_submit_wait,
 760			   (atomic_read(&fs_info->nr_async_submits) == 0));
 761	}
 
 762
 763	return 0;
 764}
 765
 766static int btree_csum_one_bio(struct bio *bio)
 
 767{
 768	struct bio_vec *bvec = bio->bi_io_vec;
 769	int bio_index = 0;
 770	struct btrfs_root *root;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 771
 772	WARN_ON(bio->bi_vcnt <= 0);
 773	while (bio_index < bio->bi_vcnt) {
 774		root = BTRFS_I(bvec->bv_page->mapping->host)->root;
 775		csum_dirty_buffer(root, bvec->bv_page);
 776		bio_index++;
 777		bvec++;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 778	}
 779	return 0;
 780}
 781
 782static int __btree_submit_bio_start(struct inode *inode, int rw,
 783				    struct bio *bio, int mirror_num,
 784				    unsigned long bio_flags,
 785				    u64 bio_offset)
 786{
 787	/*
 788	 * when we're called for a write, we're already in the async
 789	 * submission context.  Just jump into btrfs_map_bio
 790	 */
 791	btree_csum_one_bio(bio);
 792	return 0;
 793}
 794
 795static int __btree_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
 796				 int mirror_num, unsigned long bio_flags,
 797				 u64 bio_offset)
 798{
 799	/*
 800	 * when we're called for a write, we're already in the async
 801	 * submission context.  Just jump into btrfs_map_bio
 802	 */
 803	return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio, mirror_num, 1);
 804}
 805
 806static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
 807				 int mirror_num, unsigned long bio_flags,
 808				 u64 bio_offset)
 809{
 810	int ret;
 811
 812	ret = btrfs_bio_wq_end_io(BTRFS_I(inode)->root->fs_info,
 813					  bio, 1);
 814	BUG_ON(ret);
 815
 816	if (!(rw & REQ_WRITE)) {
 817		/*
 818		 * called for a read, do the setup so that checksum validation
 819		 * can happen in the async kernel threads
 820		 */
 821		return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
 822				     mirror_num, 0);
 823	}
 824
 825	/*
 826	 * kthread helpers are used to submit writes so that checksumming
 827	 * can happen in parallel across all CPUs
 828	 */
 829	return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
 830				   inode, rw, bio, mirror_num, 0,
 831				   bio_offset,
 832				   __btree_submit_bio_start,
 833				   __btree_submit_bio_done);
 834}
 835
 836#ifdef CONFIG_MIGRATION
 837static int btree_migratepage(struct address_space *mapping,
 838			struct page *newpage, struct page *page)
 839{
 840	/*
 841	 * we can't safely write a btree page from here,
 842	 * we haven't done the locking hook
 843	 */
 844	if (PageDirty(page))
 845		return -EAGAIN;
 846	/*
 847	 * Buffers may be managed in a filesystem specific way.
 848	 * We must have no buffers or drop them.
 849	 */
 850	if (page_has_private(page) &&
 851	    !try_to_release_page(page, GFP_KERNEL))
 852		return -EAGAIN;
 853	return migrate_page(mapping, newpage, page);
 854}
 855#endif
 856
 857static int btree_writepage(struct page *page, struct writeback_control *wbc)
 858{
 859	struct extent_io_tree *tree;
 860	struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 861	struct extent_buffer *eb;
 862	int was_dirty;
 863
 864	tree = &BTRFS_I(page->mapping->host)->io_tree;
 865	if (!(current->flags & PF_MEMALLOC)) {
 866		return extent_write_full_page(tree, page,
 867					      btree_get_extent, wbc);
 868	}
 869
 870	redirty_page_for_writepage(wbc, page);
 871	eb = btrfs_find_tree_block(root, page_offset(page), PAGE_CACHE_SIZE);
 872	WARN_ON(!eb);
 873
 874	was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags);
 875	if (!was_dirty) {
 876		spin_lock(&root->fs_info->delalloc_lock);
 877		root->fs_info->dirty_metadata_bytes += PAGE_CACHE_SIZE;
 878		spin_unlock(&root->fs_info->delalloc_lock);
 879	}
 880	free_extent_buffer(eb);
 881
 882	unlock_page(page);
 883	return 0;
 884}
 885
 886static int btree_writepages(struct address_space *mapping,
 887			    struct writeback_control *wbc)
 888{
 889	struct extent_io_tree *tree;
 890	tree = &BTRFS_I(mapping->host)->io_tree;
 891	if (wbc->sync_mode == WB_SYNC_NONE) {
 892		struct btrfs_root *root = BTRFS_I(mapping->host)->root;
 893		u64 num_dirty;
 894		unsigned long thresh = 32 * 1024 * 1024;
 895
 896		if (wbc->for_kupdate)
 897			return 0;
 898
 899		/* this is a bit racy, but that's ok */
 900		num_dirty = root->fs_info->dirty_metadata_bytes;
 901		if (num_dirty < thresh)
 902			return 0;
 
 903	}
 904	return extent_writepages(tree, mapping, btree_get_extent, wbc);
 905}
 906
 907static int btree_readpage(struct file *file, struct page *page)
 908{
 909	struct extent_io_tree *tree;
 910	tree = &BTRFS_I(page->mapping->host)->io_tree;
 911	return extent_read_full_page(tree, page, btree_get_extent);
 
 
 912}
 913
 914static int btree_releasepage(struct page *page, gfp_t gfp_flags)
 
 915{
 916	struct extent_io_tree *tree;
 917	struct extent_map_tree *map;
 918	int ret;
 919
 920	if (PageWriteback(page) || PageDirty(page))
 921		return 0;
 
 
 
 922
 923	tree = &BTRFS_I(page->mapping->host)->io_tree;
 924	map = &BTRFS_I(page->mapping->host)->extent_tree;
 925
 926	ret = try_release_extent_state(map, tree, page, gfp_flags);
 927	if (!ret)
 928		return 0;
 929
 930	ret = try_release_extent_buffer(tree, page);
 931	if (ret == 1) {
 932		ClearPagePrivate(page);
 933		set_page_private(page, 0);
 934		page_cache_release(page);
 935	}
 936
 937	return ret;
 938}
 939
 940static void btree_invalidatepage(struct page *page, unsigned long offset)
 941{
 942	struct extent_io_tree *tree;
 943	tree = &BTRFS_I(page->mapping->host)->io_tree;
 944	extent_invalidatepage(tree, page, offset);
 945	btree_releasepage(page, GFP_NOFS);
 946	if (PagePrivate(page)) {
 947		printk(KERN_WARNING "btrfs warning page private not zero "
 948		       "on page %llu\n", (unsigned long long)page_offset(page));
 949		ClearPagePrivate(page);
 950		set_page_private(page, 0);
 951		page_cache_release(page);
 952	}
 953}
 954
 955static const struct address_space_operations btree_aops = {
 956	.readpage	= btree_readpage,
 957	.writepage	= btree_writepage,
 958	.writepages	= btree_writepages,
 959	.releasepage	= btree_releasepage,
 960	.invalidatepage = btree_invalidatepage,
 961#ifdef CONFIG_MIGRATION
 962	.migratepage	= btree_migratepage,
 963#endif
 964};
 965
 966int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
 967			 u64 parent_transid)
 968{
 969	struct extent_buffer *buf = NULL;
 970	struct inode *btree_inode = root->fs_info->btree_inode;
 971	int ret = 0;
 
 
 
 972
 973	buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
 974	if (!buf)
 975		return 0;
 976	read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
 977				 buf, 0, 0, btree_get_extent, 0);
 978	free_extent_buffer(buf);
 979	return ret;
 980}
 981
 982struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
 983					    u64 bytenr, u32 blocksize)
 984{
 985	struct inode *btree_inode = root->fs_info->btree_inode;
 986	struct extent_buffer *eb;
 987	eb = find_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
 988				bytenr, blocksize);
 989	return eb;
 
 
 990}
 991
 992struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
 993						 u64 bytenr, u32 blocksize)
 994{
 995	struct inode *btree_inode = root->fs_info->btree_inode;
 996	struct extent_buffer *eb;
 
 
 
 997
 998	eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
 999				 bytenr, blocksize, NULL);
1000	return eb;
1001}
1002
1003
1004int btrfs_write_tree_block(struct extent_buffer *buf)
1005{
1006	return filemap_fdatawrite_range(buf->first_page->mapping, buf->start,
1007					buf->start + buf->len - 1);
 
1008}
1009
1010int btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
 
1011{
1012	return filemap_fdatawait_range(buf->first_page->mapping,
1013				       buf->start, buf->start + buf->len - 1);
1014}
 
 
 
 
1015
1016struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
1017				      u32 blocksize, u64 parent_transid)
1018{
1019	struct extent_buffer *buf = NULL;
1020	int ret;
 
 
 
 
1021
1022	buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1023	if (!buf)
1024		return NULL;
1025
1026	ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
1027
1028	if (ret == 0)
1029		set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
1030	return buf;
1031
1032}
1033
1034int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1035		     struct extent_buffer *buf)
1036{
1037	struct inode *btree_inode = root->fs_info->btree_inode;
1038	if (btrfs_header_generation(buf) ==
1039	    root->fs_info->running_transaction->transid) {
1040		btrfs_assert_tree_locked(buf);
1041
1042		if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
1043			spin_lock(&root->fs_info->delalloc_lock);
1044			if (root->fs_info->dirty_metadata_bytes >= buf->len)
1045				root->fs_info->dirty_metadata_bytes -= buf->len;
1046			else
1047				WARN_ON(1);
1048			spin_unlock(&root->fs_info->delalloc_lock);
1049		}
1050
1051		/* ugh, clear_extent_buffer_dirty needs to lock the page */
1052		btrfs_set_lock_blocking(buf);
1053		clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
1054					  buf);
1055	}
1056	return 0;
1057}
1058
1059static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
1060			u32 stripesize, struct btrfs_root *root,
1061			struct btrfs_fs_info *fs_info,
1062			u64 objectid)
1063{
1064	root->node = NULL;
1065	root->commit_root = NULL;
1066	root->sectorsize = sectorsize;
1067	root->nodesize = nodesize;
1068	root->leafsize = leafsize;
1069	root->stripesize = stripesize;
1070	root->ref_cows = 0;
1071	root->track_dirty = 0;
1072	root->in_radix = 0;
1073	root->orphan_item_inserted = 0;
1074	root->orphan_cleanup_state = 0;
1075
1076	root->fs_info = fs_info;
1077	root->objectid = objectid;
1078	root->last_trans = 0;
1079	root->highest_objectid = 0;
1080	root->name = NULL;
1081	root->inode_tree = RB_ROOT;
1082	INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
1083	root->block_rsv = NULL;
1084	root->orphan_block_rsv = NULL;
1085
1086	INIT_LIST_HEAD(&root->dirty_list);
1087	INIT_LIST_HEAD(&root->orphan_list);
1088	INIT_LIST_HEAD(&root->root_list);
1089	spin_lock_init(&root->orphan_lock);
1090	spin_lock_init(&root->inode_lock);
1091	spin_lock_init(&root->accounting_lock);
1092	mutex_init(&root->objectid_mutex);
1093	mutex_init(&root->log_mutex);
1094	init_waitqueue_head(&root->log_writer_wait);
1095	init_waitqueue_head(&root->log_commit_wait[0]);
1096	init_waitqueue_head(&root->log_commit_wait[1]);
1097	atomic_set(&root->log_commit[0], 0);
1098	atomic_set(&root->log_commit[1], 0);
1099	atomic_set(&root->log_writers, 0);
1100	root->log_batch = 0;
1101	root->log_transid = 0;
1102	root->last_log_commit = 0;
1103	extent_io_tree_init(&root->dirty_log_pages,
1104			     fs_info->btree_inode->i_mapping);
 
 
 
 
1105
1106	memset(&root->root_key, 0, sizeof(root->root_key));
1107	memset(&root->root_item, 0, sizeof(root->root_item));
1108	memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
1109	memset(&root->root_kobj, 0, sizeof(root->root_kobj));
1110	root->defrag_trans_start = fs_info->generation;
1111	init_completion(&root->kobj_unregister);
1112	root->defrag_running = 0;
1113	root->root_key.objectid = objectid;
1114	root->anon_dev = 0;
1115	return 0;
1116}
1117
1118static int find_and_setup_root(struct btrfs_root *tree_root,
1119			       struct btrfs_fs_info *fs_info,
1120			       u64 objectid,
1121			       struct btrfs_root *root)
1122{
1123	int ret;
1124	u32 blocksize;
1125	u64 generation;
1126
1127	__setup_root(tree_root->nodesize, tree_root->leafsize,
1128		     tree_root->sectorsize, tree_root->stripesize,
1129		     root, fs_info, objectid);
1130	ret = btrfs_find_last_root(tree_root, objectid,
1131				   &root->root_item, &root->root_key);
1132	if (ret > 0)
1133		return -ENOENT;
1134	BUG_ON(ret);
1135
1136	generation = btrfs_root_generation(&root->root_item);
1137	blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
1138	root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
1139				     blocksize, generation);
1140	if (!root->node || !btrfs_buffer_uptodate(root->node, generation)) {
1141		free_extent_buffer(root->node);
1142		return -EIO;
1143	}
1144	root->commit_root = btrfs_root_node(root);
1145	return 0;
1146}
1147
1148static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
1149					 struct btrfs_fs_info *fs_info)
1150{
1151	struct btrfs_root *root;
1152	struct btrfs_root *tree_root = fs_info->tree_root;
1153	struct extent_buffer *leaf;
1154
1155	root = kzalloc(sizeof(*root), GFP_NOFS);
1156	if (!root)
1157		return ERR_PTR(-ENOMEM);
1158
1159	__setup_root(tree_root->nodesize, tree_root->leafsize,
1160		     tree_root->sectorsize, tree_root->stripesize,
1161		     root, fs_info, BTRFS_TREE_LOG_OBJECTID);
1162
1163	root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1164	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1165	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
 
 
 
 
 
 
 
 
 
1166	/*
1167	 * log trees do not get reference counted because they go away
1168	 * before a real commit is actually done.  They do store pointers
1169	 * to file data extents, and those reference counts still get
1170	 * updated (along with back refs to the log tree).
 
 
 
1171	 */
1172	root->ref_cows = 0;
1173
1174	leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
1175				      BTRFS_TREE_LOG_OBJECTID, NULL, 0, 0, 0);
1176	if (IS_ERR(leaf)) {
1177		kfree(root);
1178		return ERR_CAST(leaf);
1179	}
1180
1181	memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
1182	btrfs_set_header_bytenr(leaf, leaf->start);
1183	btrfs_set_header_generation(leaf, trans->transid);
1184	btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
1185	btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
1186	root->node = leaf;
1187
1188	write_extent_buffer(root->node, root->fs_info->fsid,
1189			    (unsigned long)btrfs_header_fsid(root->node),
1190			    BTRFS_FSID_SIZE);
1191	btrfs_mark_buffer_dirty(root->node);
1192	btrfs_tree_unlock(root->node);
1193	return root;
 
1194}
1195
1196int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1197			     struct btrfs_fs_info *fs_info)
1198{
1199	struct btrfs_root *log_root;
1200
1201	log_root = alloc_log_tree(trans, fs_info);
1202	if (IS_ERR(log_root))
1203		return PTR_ERR(log_root);
 
 
 
 
 
 
 
 
 
 
1204	WARN_ON(fs_info->log_root_tree);
1205	fs_info->log_root_tree = log_root;
1206	return 0;
1207}
1208
1209int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1210		       struct btrfs_root *root)
1211{
 
1212	struct btrfs_root *log_root;
1213	struct btrfs_inode_item *inode_item;
 
1214
1215	log_root = alloc_log_tree(trans, root->fs_info);
1216	if (IS_ERR(log_root))
1217		return PTR_ERR(log_root);
1218
 
 
 
 
 
 
1219	log_root->last_trans = trans->transid;
1220	log_root->root_key.offset = root->root_key.objectid;
1221
1222	inode_item = &log_root->root_item.inode;
1223	inode_item->generation = cpu_to_le64(1);
1224	inode_item->size = cpu_to_le64(3);
1225	inode_item->nlink = cpu_to_le32(1);
1226	inode_item->nbytes = cpu_to_le64(root->leafsize);
1227	inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
 
1228
1229	btrfs_set_root_node(&log_root->root_item, log_root->node);
1230
1231	WARN_ON(root->log_root);
1232	root->log_root = log_root;
1233	root->log_transid = 0;
1234	root->last_log_commit = 0;
 
1235	return 0;
1236}
1237
1238struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
1239					       struct btrfs_key *location)
 
1240{
1241	struct btrfs_root *root;
 
1242	struct btrfs_fs_info *fs_info = tree_root->fs_info;
1243	struct btrfs_path *path;
1244	struct extent_buffer *l;
1245	u64 generation;
1246	u32 blocksize;
1247	int ret = 0;
1248
1249	root = kzalloc(sizeof(*root), GFP_NOFS);
1250	if (!root)
1251		return ERR_PTR(-ENOMEM);
1252	if (location->offset == (u64)-1) {
1253		ret = find_and_setup_root(tree_root, fs_info,
1254					  location->objectid, root);
1255		if (ret) {
1256			kfree(root);
1257			return ERR_PTR(ret);
1258		}
1259		goto out;
1260	}
1261
1262	__setup_root(tree_root->nodesize, tree_root->leafsize,
1263		     tree_root->sectorsize, tree_root->stripesize,
1264		     root, fs_info, location->objectid);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1265
1266	path = btrfs_alloc_path();
1267	if (!path) {
1268		kfree(root);
1269		return ERR_PTR(-ENOMEM);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1270	}
1271	ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
1272	if (ret == 0) {
1273		l = path->nodes[0];
1274		read_extent_buffer(l, &root->root_item,
1275				btrfs_item_ptr_offset(l, path->slots[0]),
1276				sizeof(root->root_item));
1277		memcpy(&root->root_key, location, sizeof(*location));
 
 
 
 
 
 
 
1278	}
1279	btrfs_free_path(path);
 
 
1280	if (ret) {
1281		kfree(root);
1282		if (ret > 0)
1283			ret = -ENOENT;
1284		return ERR_PTR(ret);
1285	}
1286
1287	generation = btrfs_root_generation(&root->root_item);
1288	blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
1289	root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
1290				     blocksize, generation);
1291	root->commit_root = btrfs_root_node(root);
1292	BUG_ON(!root->node);
1293out:
1294	if (location->objectid != BTRFS_TREE_LOG_OBJECTID) {
1295		root->ref_cows = 1;
1296		btrfs_check_and_init_root_item(&root->root_item);
1297	}
 
 
 
1298
 
 
 
 
 
1299	return root;
1300}
1301
1302struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
1303					      struct btrfs_key *location)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1304{
1305	struct btrfs_root *root;
1306	int ret;
1307
1308	if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1309		return fs_info->tree_root;
1310	if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
1311		return fs_info->extent_root;
1312	if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
1313		return fs_info->chunk_root;
1314	if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
1315		return fs_info->dev_root;
1316	if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
1317		return fs_info->csum_root;
1318again:
1319	spin_lock(&fs_info->fs_roots_radix_lock);
1320	root = radix_tree_lookup(&fs_info->fs_roots_radix,
1321				 (unsigned long)location->objectid);
 
 
 
 
 
1322	spin_unlock(&fs_info->fs_roots_radix_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1323	if (root)
1324		return root;
1325
1326	root = btrfs_read_fs_root_no_radix(fs_info->tree_root, location);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1327	if (IS_ERR(root))
1328		return root;
1329
1330	root->free_ino_ctl = kzalloc(sizeof(*root->free_ino_ctl), GFP_NOFS);
1331	root->free_ino_pinned = kzalloc(sizeof(*root->free_ino_pinned),
1332					GFP_NOFS);
1333	if (!root->free_ino_pinned || !root->free_ino_ctl) {
1334		ret = -ENOMEM;
1335		goto fail;
1336	}
1337
1338	btrfs_init_free_ino_ctl(root);
1339	mutex_init(&root->fs_commit_mutex);
1340	spin_lock_init(&root->cache_lock);
1341	init_waitqueue_head(&root->cache_wait);
1342
1343	ret = get_anon_bdev(&root->anon_dev);
1344	if (ret)
1345		goto fail;
1346
1347	if (btrfs_root_refs(&root->root_item) == 0) {
1348		ret = -ENOENT;
 
1349		goto fail;
1350	}
 
 
 
1351
1352	ret = btrfs_find_orphan_item(fs_info->tree_root, location->objectid);
 
1353	if (ret < 0)
1354		goto fail;
1355	if (ret == 0)
1356		root->orphan_item_inserted = 1;
1357
1358	ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
1359	if (ret)
1360		goto fail;
1361
1362	spin_lock(&fs_info->fs_roots_radix_lock);
1363	ret = radix_tree_insert(&fs_info->fs_roots_radix,
1364				(unsigned long)root->root_key.objectid,
1365				root);
1366	if (ret == 0)
1367		root->in_radix = 1;
1368
1369	spin_unlock(&fs_info->fs_roots_radix_lock);
1370	radix_tree_preload_end();
1371	if (ret) {
1372		if (ret == -EEXIST) {
1373			free_fs_root(root);
1374			goto again;
1375		}
1376		goto fail;
1377	}
1378
1379	ret = btrfs_find_dead_roots(fs_info->tree_root,
1380				    root->root_key.objectid);
1381	WARN_ON(ret);
1382	return root;
1383fail:
1384	free_fs_root(root);
 
 
 
 
 
 
 
 
1385	return ERR_PTR(ret);
1386}
1387
1388static int btrfs_congested_fn(void *congested_data, int bdi_bits)
 
 
 
 
 
 
 
 
1389{
1390	struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
1391	int ret = 0;
1392	struct btrfs_device *device;
1393	struct backing_dev_info *bdi;
1394
1395	rcu_read_lock();
1396	list_for_each_entry_rcu(device, &info->fs_devices->devices, dev_list) {
1397		if (!device->bdev)
1398			continue;
1399		bdi = blk_get_backing_dev_info(device->bdev);
1400		if (bdi && bdi_congested(bdi, bdi_bits)) {
1401			ret = 1;
1402			break;
1403		}
1404	}
1405	rcu_read_unlock();
1406	return ret;
1407}
1408
1409/*
1410 * If this fails, caller must call bdi_destroy() to get rid of the
1411 * bdi again.
 
 
 
 
 
 
 
 
 
 
 
1412 */
1413static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
 
 
1414{
1415	int err;
 
 
 
1416
1417	bdi->capabilities = BDI_CAP_MAP_COPY;
1418	err = bdi_setup_and_register(bdi, "btrfs", BDI_CAP_MAP_COPY);
1419	if (err)
1420		return err;
 
 
 
 
 
 
 
 
 
1421
1422	bdi->ra_pages	= default_backing_dev_info.ra_pages;
1423	bdi->congested_fn	= btrfs_congested_fn;
1424	bdi->congested_data	= info;
1425	return 0;
 
 
 
1426}
1427
1428static int bio_ready_for_csum(struct bio *bio)
1429{
1430	u64 length = 0;
1431	u64 buf_len = 0;
1432	u64 start = 0;
1433	struct page *page;
1434	struct extent_io_tree *io_tree = NULL;
1435	struct bio_vec *bvec;
1436	int i;
1437	int ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
1438
1439	bio_for_each_segment(bvec, bio, i) {
1440		page = bvec->bv_page;
1441		if (page->private == EXTENT_PAGE_PRIVATE) {
1442			length += bvec->bv_len;
1443			continue;
 
 
1444		}
1445		if (!page->private) {
1446			length += bvec->bv_len;
1447			continue;
1448		}
1449		length = bvec->bv_len;
1450		buf_len = page->private >> 2;
1451		start = page_offset(page) + bvec->bv_offset;
1452		io_tree = &BTRFS_I(page->mapping->host)->io_tree;
1453	}
1454	/* are we fully contained in this bio? */
1455	if (buf_len <= length)
1456		return 1;
1457
1458	ret = extent_range_uptodate(io_tree, start + length,
1459				    start + buf_len - 1);
1460	return ret;
1461}
1462
1463/*
1464 * called by the kthread helper functions to finally call the bio end_io
1465 * functions.  This is where read checksum verification actually happens
1466 */
1467static void end_workqueue_fn(struct btrfs_work *work)
1468{
1469	struct bio *bio;
1470	struct end_io_wq *end_io_wq;
1471	struct btrfs_fs_info *fs_info;
1472	int error;
1473
1474	end_io_wq = container_of(work, struct end_io_wq, work);
1475	bio = end_io_wq->bio;
1476	fs_info = end_io_wq->info;
1477
1478	/* metadata bio reads are special because the whole tree block must
1479	 * be checksummed at once.  This makes sure the entire block is in
1480	 * ram and up to date before trying to verify things.  For
1481	 * blocksize <= pagesize, it is basically a noop
1482	 */
1483	if (!(bio->bi_rw & REQ_WRITE) && end_io_wq->metadata &&
1484	    !bio_ready_for_csum(bio)) {
1485		btrfs_queue_worker(&fs_info->endio_meta_workers,
1486				   &end_io_wq->work);
1487		return;
1488	}
1489	error = end_io_wq->error;
1490	bio->bi_private = end_io_wq->private;
1491	bio->bi_end_io = end_io_wq->end_io;
1492	kfree(end_io_wq);
1493	bio_endio(bio, error);
1494}
1495
1496static int cleaner_kthread(void *arg)
1497{
1498	struct btrfs_root *root = arg;
1499
1500	do {
1501		vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
 
 
 
1502
1503		if (!(root->fs_info->sb->s_flags & MS_RDONLY) &&
1504		    mutex_trylock(&root->fs_info->cleaner_mutex)) {
1505			btrfs_run_delayed_iputs(root);
1506			btrfs_clean_old_snapshots(root);
1507			mutex_unlock(&root->fs_info->cleaner_mutex);
1508			btrfs_run_defrag_inodes(root->fs_info);
1509		}
 
 
1510
1511		if (freezing(current)) {
1512			refrigerator();
1513		} else {
 
 
 
 
 
 
 
 
 
 
1514			set_current_state(TASK_INTERRUPTIBLE);
1515			if (!kthread_should_stop())
1516				schedule();
1517			__set_current_state(TASK_RUNNING);
1518		}
1519	} while (!kthread_should_stop());
1520	return 0;
1521}
1522
1523static int transaction_kthread(void *arg)
1524{
1525	struct btrfs_root *root = arg;
 
1526	struct btrfs_trans_handle *trans;
1527	struct btrfs_transaction *cur;
1528	u64 transid;
1529	unsigned long now;
1530	unsigned long delay;
1531	int ret;
1532
1533	do {
1534		delay = HZ * 30;
1535		vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
1536		mutex_lock(&root->fs_info->transaction_kthread_mutex);
1537
1538		spin_lock(&root->fs_info->trans_lock);
1539		cur = root->fs_info->running_transaction;
1540		if (!cur) {
1541			spin_unlock(&root->fs_info->trans_lock);
1542			goto sleep;
1543		}
1544
1545		now = get_seconds();
1546		if (!cur->blocked &&
1547		    (now < cur->start_time || now - cur->start_time < 30)) {
1548			spin_unlock(&root->fs_info->trans_lock);
1549			delay = HZ * 5;
 
 
 
1550			goto sleep;
1551		}
1552		transid = cur->transid;
1553		spin_unlock(&root->fs_info->trans_lock);
1554
1555		trans = btrfs_join_transaction(root);
1556		BUG_ON(IS_ERR(trans));
 
 
 
 
 
1557		if (transid == trans->transid) {
1558			ret = btrfs_commit_transaction(trans, root);
1559			BUG_ON(ret);
1560		} else {
1561			btrfs_end_transaction(trans, root);
1562		}
1563sleep:
1564		wake_up_process(root->fs_info->cleaner_kthread);
1565		mutex_unlock(&root->fs_info->transaction_kthread_mutex);
1566
1567		if (freezing(current)) {
1568			refrigerator();
1569		} else {
1570			set_current_state(TASK_INTERRUPTIBLE);
1571			if (!kthread_should_stop() &&
1572			    !btrfs_transaction_blocked(root->fs_info))
1573				schedule_timeout(delay);
1574			__set_current_state(TASK_RUNNING);
1575		}
1576	} while (!kthread_should_stop());
1577	return 0;
1578}
1579
1580struct btrfs_root *open_ctree(struct super_block *sb,
1581			      struct btrfs_fs_devices *fs_devices,
1582			      char *options)
 
 
 
 
 
 
 
1583{
1584	u32 sectorsize;
1585	u32 nodesize;
1586	u32 leafsize;
1587	u32 blocksize;
1588	u32 stripesize;
1589	u64 generation;
1590	u64 features;
1591	struct btrfs_key location;
1592	struct buffer_head *bh;
1593	struct btrfs_root *extent_root = kzalloc(sizeof(struct btrfs_root),
1594						 GFP_NOFS);
1595	struct btrfs_root *csum_root = kzalloc(sizeof(struct btrfs_root),
1596						 GFP_NOFS);
1597	struct btrfs_root *tree_root = btrfs_sb(sb);
1598	struct btrfs_fs_info *fs_info = NULL;
1599	struct btrfs_root *chunk_root = kzalloc(sizeof(struct btrfs_root),
1600						GFP_NOFS);
1601	struct btrfs_root *dev_root = kzalloc(sizeof(struct btrfs_root),
1602					      GFP_NOFS);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1603	struct btrfs_root *log_tree_root;
 
 
 
 
 
 
 
 
 
 
 
 
 
1604
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1605	int ret;
1606	int err = -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
1607
1608	struct btrfs_super_block *disk_super;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1609
1610	if (!extent_root || !tree_root || !tree_root->fs_info ||
1611	    !chunk_root || !dev_root || !csum_root) {
1612		err = -ENOMEM;
1613		goto fail;
 
 
 
 
 
 
 
 
 
 
 
 
1614	}
1615	fs_info = tree_root->fs_info;
 
 
 
 
 
1616
1617	ret = init_srcu_struct(&fs_info->subvol_srcu);
1618	if (ret) {
1619		err = ret;
1620		goto fail;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1621	}
1622
1623	ret = setup_bdi(fs_info, &fs_info->bdi);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1624	if (ret) {
1625		err = ret;
1626		goto fail_srcu;
1627	}
 
 
1628
1629	fs_info->btree_inode = new_inode(sb);
1630	if (!fs_info->btree_inode) {
1631		err = -ENOMEM;
1632		goto fail_bdi;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1633	}
1634
1635	mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
 
1636
 
 
1637	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
 
1638	INIT_LIST_HEAD(&fs_info->trans_list);
1639	INIT_LIST_HEAD(&fs_info->dead_roots);
1640	INIT_LIST_HEAD(&fs_info->delayed_iputs);
1641	INIT_LIST_HEAD(&fs_info->hashers);
1642	INIT_LIST_HEAD(&fs_info->delalloc_inodes);
1643	INIT_LIST_HEAD(&fs_info->ordered_operations);
1644	INIT_LIST_HEAD(&fs_info->caching_block_groups);
1645	spin_lock_init(&fs_info->delalloc_lock);
1646	spin_lock_init(&fs_info->trans_lock);
1647	spin_lock_init(&fs_info->ref_cache_lock);
1648	spin_lock_init(&fs_info->fs_roots_radix_lock);
1649	spin_lock_init(&fs_info->delayed_iput_lock);
1650	spin_lock_init(&fs_info->defrag_inodes_lock);
 
 
 
 
 
 
 
 
 
 
1651	mutex_init(&fs_info->reloc_mutex);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1652
1653	init_completion(&fs_info->kobj_unregister);
1654	fs_info->tree_root = tree_root;
1655	fs_info->extent_root = extent_root;
1656	fs_info->csum_root = csum_root;
1657	fs_info->chunk_root = chunk_root;
1658	fs_info->dev_root = dev_root;
1659	fs_info->fs_devices = fs_devices;
1660	INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
1661	INIT_LIST_HEAD(&fs_info->space_info);
1662	btrfs_mapping_init(&fs_info->mapping_tree);
1663	btrfs_init_block_rsv(&fs_info->global_block_rsv);
1664	btrfs_init_block_rsv(&fs_info->delalloc_block_rsv);
1665	btrfs_init_block_rsv(&fs_info->trans_block_rsv);
1666	btrfs_init_block_rsv(&fs_info->chunk_block_rsv);
1667	btrfs_init_block_rsv(&fs_info->empty_block_rsv);
1668	INIT_LIST_HEAD(&fs_info->durable_block_rsv_list);
1669	mutex_init(&fs_info->durable_block_rsv_mutex);
1670	atomic_set(&fs_info->nr_async_submits, 0);
 
 
 
 
 
 
 
 
 
 
 
 
1671	atomic_set(&fs_info->async_delalloc_pages, 0);
1672	atomic_set(&fs_info->async_submit_draining, 0);
1673	atomic_set(&fs_info->nr_async_bios, 0);
1674	atomic_set(&fs_info->defrag_running, 0);
1675	fs_info->sb = sb;
1676	fs_info->max_inline = 8192 * 1024;
 
 
1677	fs_info->metadata_ratio = 0;
1678	fs_info->defrag_inodes = RB_ROOT;
1679	fs_info->trans_no_join = 0;
 
 
 
1680
1681	fs_info->thread_pool_size = min_t(unsigned long,
1682					  num_online_cpus() + 2, 8);
1683
1684	INIT_LIST_HEAD(&fs_info->ordered_extents);
1685	spin_lock_init(&fs_info->ordered_extent_lock);
1686	fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
1687					GFP_NOFS);
1688	if (!fs_info->delayed_root) {
1689		err = -ENOMEM;
1690		goto fail_iput;
1691	}
1692	btrfs_init_delayed_root(fs_info->delayed_root);
1693
1694	mutex_init(&fs_info->scrub_lock);
1695	atomic_set(&fs_info->scrubs_running, 0);
1696	atomic_set(&fs_info->scrub_pause_req, 0);
1697	atomic_set(&fs_info->scrubs_paused, 0);
1698	atomic_set(&fs_info->scrub_cancel_req, 0);
1699	init_waitqueue_head(&fs_info->scrub_pause_wait);
1700	init_rwsem(&fs_info->scrub_super_lock);
1701	fs_info->scrub_workers_refcnt = 0;
1702
1703	sb->s_blocksize = 4096;
1704	sb->s_blocksize_bits = blksize_bits(4096);
1705	sb->s_bdi = &fs_info->bdi;
1706
1707	fs_info->btree_inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
1708	fs_info->btree_inode->i_nlink = 1;
1709	/*
1710	 * we set the i_size on the btree inode to the max possible int.
1711	 * the real end of the address space is determined by all of
1712	 * the devices in the system
1713	 */
1714	fs_info->btree_inode->i_size = OFFSET_MAX;
1715	fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
1716	fs_info->btree_inode->i_mapping->backing_dev_info = &fs_info->bdi;
1717
1718	RB_CLEAR_NODE(&BTRFS_I(fs_info->btree_inode)->rb_node);
1719	extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree,
1720			     fs_info->btree_inode->i_mapping);
1721	extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree);
1722
1723	BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops;
1724
1725	BTRFS_I(fs_info->btree_inode)->root = tree_root;
1726	memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
1727	       sizeof(struct btrfs_key));
1728	BTRFS_I(fs_info->btree_inode)->dummy_inode = 1;
1729	insert_inode_hash(fs_info->btree_inode);
1730
1731	spin_lock_init(&fs_info->block_group_cache_lock);
1732	fs_info->block_group_cache_tree = RB_ROOT;
1733
1734	extent_io_tree_init(&fs_info->freed_extents[0],
1735			     fs_info->btree_inode->i_mapping);
1736	extent_io_tree_init(&fs_info->freed_extents[1],
1737			     fs_info->btree_inode->i_mapping);
1738	fs_info->pinned_extents = &fs_info->freed_extents[0];
1739	fs_info->do_barriers = 1;
1740
 
 
1741
1742	mutex_init(&fs_info->ordered_operations_mutex);
1743	mutex_init(&fs_info->tree_log_mutex);
1744	mutex_init(&fs_info->chunk_mutex);
1745	mutex_init(&fs_info->transaction_kthread_mutex);
1746	mutex_init(&fs_info->cleaner_mutex);
1747	mutex_init(&fs_info->volume_mutex);
1748	init_rwsem(&fs_info->extent_commit_sem);
1749	init_rwsem(&fs_info->cleanup_work_sem);
1750	init_rwsem(&fs_info->subvol_sem);
 
 
 
 
 
1751
1752	btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
1753	btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
1754
1755	init_waitqueue_head(&fs_info->transaction_throttle);
1756	init_waitqueue_head(&fs_info->transaction_wait);
1757	init_waitqueue_head(&fs_info->transaction_blocked_wait);
1758	init_waitqueue_head(&fs_info->async_submit_wait);
 
 
 
 
 
 
 
 
 
 
1759
1760	__setup_root(4096, 4096, 4096, 4096, tree_root,
1761		     fs_info, BTRFS_ROOT_TREE_OBJECTID);
 
 
 
 
 
 
1762
1763	bh = btrfs_read_dev_super(fs_devices->latest_bdev);
1764	if (!bh) {
1765		err = -EINVAL;
1766		goto fail_alloc;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1767	}
1768
1769	memcpy(&fs_info->super_copy, bh->b_data, sizeof(fs_info->super_copy));
1770	memcpy(&fs_info->super_for_commit, &fs_info->super_copy,
1771	       sizeof(fs_info->super_for_commit));
1772	brelse(bh);
1773
1774	memcpy(fs_info->fsid, fs_info->super_copy.fsid, BTRFS_FSID_SIZE);
 
1775
1776	disk_super = &fs_info->super_copy;
1777	if (!btrfs_super_root(disk_super))
1778		goto fail_alloc;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1779
1780	/* check FS state, whether FS is broken. */
1781	fs_info->fs_state |= btrfs_super_flags(disk_super);
1782
1783	btrfs_check_super_valid(fs_info, sb->s_flags & MS_RDONLY);
 
 
 
 
 
 
 
1784
 
1785	/*
1786	 * In the long term, we'll store the compression type in the super
1787	 * block, and it'll be used for per file compression control.
1788	 */
1789	fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
 
 
 
 
 
 
 
 
 
1790
1791	ret = btrfs_parse_options(tree_root, options);
1792	if (ret) {
1793		err = ret;
1794		goto fail_alloc;
1795	}
1796
1797	features = btrfs_super_incompat_flags(disk_super) &
1798		~BTRFS_FEATURE_INCOMPAT_SUPP;
1799	if (features) {
1800		printk(KERN_ERR "BTRFS: couldn't mount because of "
1801		       "unsupported optional features (%Lx).\n",
1802		       (unsigned long long)features);
1803		err = -EINVAL;
 
1804		goto fail_alloc;
1805	}
1806
1807	features = btrfs_super_incompat_flags(disk_super);
1808	features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
1809	if (tree_root->fs_info->compress_type & BTRFS_COMPRESS_LZO)
1810		features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
1811	btrfs_set_super_incompat_flags(disk_super, features);
1812
1813	features = btrfs_super_compat_ro_flags(disk_super) &
1814		~BTRFS_FEATURE_COMPAT_RO_SUPP;
1815	if (!(sb->s_flags & MS_RDONLY) && features) {
1816		printk(KERN_ERR "BTRFS: couldn't mount RDWR because of "
1817		       "unsupported option features (%Lx).\n",
1818		       (unsigned long long)features);
1819		err = -EINVAL;
 
 
 
 
1820		goto fail_alloc;
1821	}
1822
1823	btrfs_init_workers(&fs_info->generic_worker,
1824			   "genwork", 1, NULL);
 
 
 
1825
1826	btrfs_init_workers(&fs_info->workers, "worker",
1827			   fs_info->thread_pool_size,
1828			   &fs_info->generic_worker);
1829
1830	btrfs_init_workers(&fs_info->delalloc_workers, "delalloc",
1831			   fs_info->thread_pool_size,
1832			   &fs_info->generic_worker);
1833
1834	btrfs_init_workers(&fs_info->submit_workers, "submit",
1835			   min_t(u64, fs_devices->num_devices,
1836			   fs_info->thread_pool_size),
1837			   &fs_info->generic_worker);
1838
1839	btrfs_init_workers(&fs_info->caching_workers, "cache",
1840			   2, &fs_info->generic_worker);
1841
1842	/* a higher idle thresh on the submit workers makes it much more
1843	 * likely that bios will be send down in a sane order to the
1844	 * devices
1845	 */
1846	fs_info->submit_workers.idle_thresh = 64;
1847
1848	fs_info->workers.idle_thresh = 16;
1849	fs_info->workers.ordered = 1;
1850
1851	fs_info->delalloc_workers.idle_thresh = 2;
1852	fs_info->delalloc_workers.ordered = 1;
1853
1854	btrfs_init_workers(&fs_info->fixup_workers, "fixup", 1,
1855			   &fs_info->generic_worker);
1856	btrfs_init_workers(&fs_info->endio_workers, "endio",
1857			   fs_info->thread_pool_size,
1858			   &fs_info->generic_worker);
1859	btrfs_init_workers(&fs_info->endio_meta_workers, "endio-meta",
1860			   fs_info->thread_pool_size,
1861			   &fs_info->generic_worker);
1862	btrfs_init_workers(&fs_info->endio_meta_write_workers,
1863			   "endio-meta-write", fs_info->thread_pool_size,
1864			   &fs_info->generic_worker);
1865	btrfs_init_workers(&fs_info->endio_write_workers, "endio-write",
1866			   fs_info->thread_pool_size,
1867			   &fs_info->generic_worker);
1868	btrfs_init_workers(&fs_info->endio_freespace_worker, "freespace-write",
1869			   1, &fs_info->generic_worker);
1870	btrfs_init_workers(&fs_info->delayed_workers, "delayed-meta",
1871			   fs_info->thread_pool_size,
1872			   &fs_info->generic_worker);
1873
1874	/*
1875	 * endios are largely parallel and should have a very
1876	 * low idle thresh
1877	 */
1878	fs_info->endio_workers.idle_thresh = 4;
1879	fs_info->endio_meta_workers.idle_thresh = 4;
1880
1881	fs_info->endio_write_workers.idle_thresh = 2;
1882	fs_info->endio_meta_write_workers.idle_thresh = 2;
1883
1884	btrfs_start_workers(&fs_info->workers, 1);
1885	btrfs_start_workers(&fs_info->generic_worker, 1);
1886	btrfs_start_workers(&fs_info->submit_workers, 1);
1887	btrfs_start_workers(&fs_info->delalloc_workers, 1);
1888	btrfs_start_workers(&fs_info->fixup_workers, 1);
1889	btrfs_start_workers(&fs_info->endio_workers, 1);
1890	btrfs_start_workers(&fs_info->endio_meta_workers, 1);
1891	btrfs_start_workers(&fs_info->endio_meta_write_workers, 1);
1892	btrfs_start_workers(&fs_info->endio_write_workers, 1);
1893	btrfs_start_workers(&fs_info->endio_freespace_worker, 1);
1894	btrfs_start_workers(&fs_info->delayed_workers, 1);
1895	btrfs_start_workers(&fs_info->caching_workers, 1);
1896
1897	fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
1898	fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
1899				    4 * 1024 * 1024 / PAGE_CACHE_SIZE);
1900
 
1901	nodesize = btrfs_super_nodesize(disk_super);
1902	leafsize = btrfs_super_leafsize(disk_super);
1903	sectorsize = btrfs_super_sectorsize(disk_super);
1904	stripesize = btrfs_super_stripesize(disk_super);
1905	tree_root->nodesize = nodesize;
1906	tree_root->leafsize = leafsize;
1907	tree_root->sectorsize = sectorsize;
1908	tree_root->stripesize = stripesize;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1909
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1910	sb->s_blocksize = sectorsize;
1911	sb->s_blocksize_bits = blksize_bits(sectorsize);
1912
1913	if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
1914		    sizeof(disk_super->magic))) {
1915		printk(KERN_INFO "btrfs: valid FS not found on %s\n", sb->s_id);
1916		goto fail_sb_buffer;
1917	}
1918
1919	mutex_lock(&fs_info->chunk_mutex);
1920	ret = btrfs_read_sys_array(tree_root);
1921	mutex_unlock(&fs_info->chunk_mutex);
1922	if (ret) {
1923		printk(KERN_WARNING "btrfs: failed to read the system "
1924		       "array on %s\n", sb->s_id);
1925		goto fail_sb_buffer;
1926	}
1927
1928	blocksize = btrfs_level_size(tree_root,
1929				     btrfs_super_chunk_root_level(disk_super));
1930	generation = btrfs_super_chunk_root_generation(disk_super);
1931
1932	__setup_root(nodesize, leafsize, sectorsize, stripesize,
1933		     chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
1934
1935	chunk_root->node = read_tree_block(chunk_root,
1936					   btrfs_super_chunk_root(disk_super),
1937					   blocksize, generation);
1938	BUG_ON(!chunk_root->node);
1939	if (!test_bit(EXTENT_BUFFER_UPTODATE, &chunk_root->node->bflags)) {
1940		printk(KERN_WARNING "btrfs: failed to read chunk root on %s\n",
1941		       sb->s_id);
1942		goto fail_chunk_root;
1943	}
1944	btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
1945	chunk_root->commit_root = btrfs_root_node(chunk_root);
1946
1947	read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
1948	   (unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
1949	   BTRFS_UUID_SIZE);
1950
1951	mutex_lock(&fs_info->chunk_mutex);
1952	ret = btrfs_read_chunk_tree(chunk_root);
1953	mutex_unlock(&fs_info->chunk_mutex);
1954	if (ret) {
1955		printk(KERN_WARNING "btrfs: failed to read chunk tree on %s\n",
1956		       sb->s_id);
1957		goto fail_chunk_root;
1958	}
1959
1960	btrfs_close_extra_devices(fs_devices);
1961
1962	blocksize = btrfs_level_size(tree_root,
1963				     btrfs_super_root_level(disk_super));
1964	generation = btrfs_super_generation(disk_super);
1965
1966	tree_root->node = read_tree_block(tree_root,
1967					  btrfs_super_root(disk_super),
1968					  blocksize, generation);
1969	if (!tree_root->node)
1970		goto fail_chunk_root;
1971	if (!test_bit(EXTENT_BUFFER_UPTODATE, &tree_root->node->bflags)) {
1972		printk(KERN_WARNING "btrfs: failed to read tree root on %s\n",
1973		       sb->s_id);
1974		goto fail_tree_root;
1975	}
1976	btrfs_set_root_node(&tree_root->root_item, tree_root->node);
1977	tree_root->commit_root = btrfs_root_node(tree_root);
1978
1979	ret = find_and_setup_root(tree_root, fs_info,
1980				  BTRFS_EXTENT_TREE_OBJECTID, extent_root);
1981	if (ret)
1982		goto fail_tree_root;
1983	extent_root->track_dirty = 1;
 
 
 
 
 
 
 
 
1984
1985	ret = find_and_setup_root(tree_root, fs_info,
1986				  BTRFS_DEV_TREE_OBJECTID, dev_root);
1987	if (ret)
1988		goto fail_extent_root;
1989	dev_root->track_dirty = 1;
1990
1991	ret = find_and_setup_root(tree_root, fs_info,
1992				  BTRFS_CSUM_TREE_OBJECTID, csum_root);
1993	if (ret)
1994		goto fail_dev_root;
 
 
 
 
 
 
 
1995
1996	csum_root->track_dirty = 1;
 
 
 
 
 
 
 
 
 
 
1997
1998	fs_info->generation = generation;
1999	fs_info->last_trans_committed = generation;
2000	fs_info->data_alloc_profile = (u64)-1;
2001	fs_info->metadata_alloc_profile = (u64)-1;
2002	fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
 
 
 
 
 
 
 
 
 
 
 
 
 
2003
2004	ret = btrfs_init_space_info(fs_info);
2005	if (ret) {
2006		printk(KERN_ERR "Failed to initial space info: %d\n", ret);
2007		goto fail_block_groups;
2008	}
2009
2010	ret = btrfs_read_block_groups(extent_root);
2011	if (ret) {
2012		printk(KERN_ERR "Failed to read block groups: %d\n", ret);
 
2013		goto fail_block_groups;
2014	}
2015
2016	fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
2017					       "btrfs-cleaner");
2018	if (IS_ERR(fs_info->cleaner_kthread))
 
2019		goto fail_block_groups;
 
2020
2021	fs_info->transaction_kthread = kthread_run(transaction_kthread,
2022						   tree_root,
2023						   "btrfs-transaction");
2024	if (IS_ERR(fs_info->transaction_kthread))
2025		goto fail_cleaner;
2026
2027	if (!btrfs_test_opt(tree_root, SSD) &&
2028	    !btrfs_test_opt(tree_root, NOSSD) &&
2029	    !fs_info->fs_devices->rotating) {
2030		printk(KERN_INFO "Btrfs detected SSD devices, enabling SSD "
2031		       "mode\n");
2032		btrfs_set_opt(fs_info->mount_opt, SSD);
2033	}
2034
2035	/* do not make disk changes in broken FS */
2036	if (btrfs_super_log_root(disk_super) != 0 &&
2037	    !(fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)) {
2038		u64 bytenr = btrfs_super_log_root(disk_super);
 
2039
2040		if (fs_devices->rw_devices == 0) {
2041			printk(KERN_WARNING "Btrfs log replay required "
2042			       "on RO media\n");
2043			err = -EIO;
2044			goto fail_trans_kthread;
2045		}
2046		blocksize =
2047		     btrfs_level_size(tree_root,
2048				      btrfs_super_log_root_level(disk_super));
2049
2050		log_tree_root = kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
2051		if (!log_tree_root) {
2052			err = -ENOMEM;
2053			goto fail_trans_kthread;
2054		}
2055
2056		__setup_root(nodesize, leafsize, sectorsize, stripesize,
2057			     log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
 
 
 
 
 
2058
2059		log_tree_root->node = read_tree_block(tree_root, bytenr,
2060						      blocksize,
2061						      generation + 1);
2062		ret = btrfs_recover_log_trees(log_tree_root);
2063		BUG_ON(ret);
 
2064
2065		if (sb->s_flags & MS_RDONLY) {
2066			ret =  btrfs_commit_super(tree_root);
2067			BUG_ON(ret);
2068		}
 
 
2069	}
2070
2071	ret = btrfs_find_orphan_roots(tree_root);
2072	BUG_ON(ret);
 
2073
2074	if (!(sb->s_flags & MS_RDONLY)) {
2075		ret = btrfs_cleanup_fs_roots(fs_info);
2076		BUG_ON(ret);
2077
2078		ret = btrfs_recover_relocation(tree_root);
2079		if (ret < 0) {
2080			printk(KERN_WARNING
2081			       "btrfs: failed to recover relocation\n");
2082			err = -EINVAL;
2083			goto fail_trans_kthread;
2084		}
 
 
 
 
 
 
 
 
2085	}
2086
2087	location.objectid = BTRFS_FS_TREE_OBJECTID;
2088	location.type = BTRFS_ROOT_ITEM_KEY;
2089	location.offset = (u64)-1;
2090
2091	fs_info->fs_root = btrfs_read_fs_root_no_name(fs_info, &location);
2092	if (!fs_info->fs_root)
2093		goto fail_trans_kthread;
2094	if (IS_ERR(fs_info->fs_root)) {
2095		err = PTR_ERR(fs_info->fs_root);
2096		goto fail_trans_kthread;
2097	}
 
2098
2099	if (!(sb->s_flags & MS_RDONLY)) {
2100		down_read(&fs_info->cleanup_work_sem);
2101		err = btrfs_orphan_cleanup(fs_info->fs_root);
2102		if (!err)
2103			err = btrfs_orphan_cleanup(fs_info->tree_root);
2104		up_read(&fs_info->cleanup_work_sem);
2105		if (err) {
2106			close_ctree(tree_root);
2107			return ERR_PTR(err);
 
2108		}
2109	}
2110
2111	return tree_root;
 
 
 
 
 
 
2112
 
 
2113fail_trans_kthread:
2114	kthread_stop(fs_info->transaction_kthread);
 
 
2115fail_cleaner:
2116	kthread_stop(fs_info->cleaner_kthread);
2117
2118	/*
2119	 * make sure we're done with the btree inode before we stop our
2120	 * kthreads
2121	 */
2122	filemap_write_and_wait(fs_info->btree_inode->i_mapping);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2123	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
2124
2125fail_block_groups:
 
2126	btrfs_free_block_groups(fs_info);
2127	free_extent_buffer(csum_root->node);
2128	free_extent_buffer(csum_root->commit_root);
2129fail_dev_root:
2130	free_extent_buffer(dev_root->node);
2131	free_extent_buffer(dev_root->commit_root);
2132fail_extent_root:
2133	free_extent_buffer(extent_root->node);
2134	free_extent_buffer(extent_root->commit_root);
2135fail_tree_root:
2136	free_extent_buffer(tree_root->node);
2137	free_extent_buffer(tree_root->commit_root);
2138fail_chunk_root:
2139	free_extent_buffer(chunk_root->node);
2140	free_extent_buffer(chunk_root->commit_root);
2141fail_sb_buffer:
2142	btrfs_stop_workers(&fs_info->generic_worker);
2143	btrfs_stop_workers(&fs_info->fixup_workers);
2144	btrfs_stop_workers(&fs_info->delalloc_workers);
2145	btrfs_stop_workers(&fs_info->workers);
2146	btrfs_stop_workers(&fs_info->endio_workers);
2147	btrfs_stop_workers(&fs_info->endio_meta_workers);
2148	btrfs_stop_workers(&fs_info->endio_meta_write_workers);
2149	btrfs_stop_workers(&fs_info->endio_write_workers);
2150	btrfs_stop_workers(&fs_info->endio_freespace_worker);
2151	btrfs_stop_workers(&fs_info->submit_workers);
2152	btrfs_stop_workers(&fs_info->delayed_workers);
2153	btrfs_stop_workers(&fs_info->caching_workers);
2154fail_alloc:
2155	kfree(fs_info->delayed_root);
2156fail_iput:
2157	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
2158	iput(fs_info->btree_inode);
 
 
 
 
 
 
2159
2160	btrfs_close_devices(fs_info->fs_devices);
2161	btrfs_mapping_tree_free(&fs_info->mapping_tree);
2162fail_bdi:
2163	bdi_destroy(&fs_info->bdi);
2164fail_srcu:
2165	cleanup_srcu_struct(&fs_info->subvol_srcu);
2166fail:
2167	kfree(extent_root);
2168	kfree(tree_root);
2169	kfree(fs_info);
2170	kfree(chunk_root);
2171	kfree(dev_root);
2172	kfree(csum_root);
2173	return ERR_PTR(err);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2174}
2175
2176static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
 
2177{
2178	char b[BDEVNAME_SIZE];
 
 
 
 
2179
2180	if (uptodate) {
2181		set_buffer_uptodate(bh);
2182	} else {
2183		printk_ratelimited(KERN_WARNING "lost page write due to "
2184					"I/O error on %s\n",
2185				       bdevname(bh->b_bdev, b));
2186		/* note, we dont' set_buffer_write_io_error because we have
2187		 * our own ways of dealing with the IO errors
 
 
 
 
 
 
 
 
 
2188		 */
2189		clear_buffer_uptodate(bh);
 
 
2190	}
2191	unlock_buffer(bh);
2192	put_bh(bh);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2193}
2194
2195struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
 
2196{
2197	struct buffer_head *bh;
2198	struct buffer_head *latest = NULL;
2199	struct btrfs_super_block *super;
2200	int i;
2201	u64 transid = 0;
2202	u64 bytenr;
2203
2204	/* we would like to check all the supers, but that would make
2205	 * a btrfs mount succeed after a mkfs from a different FS.
2206	 * So, we need to add a special mount option to scan for
2207	 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
2208	 */
2209	for (i = 0; i < 1; i++) {
2210		bytenr = btrfs_sb_offset(i);
2211		if (bytenr + 4096 >= i_size_read(bdev->bd_inode))
2212			break;
2213		bh = __bread(bdev, bytenr / 4096, 4096);
2214		if (!bh)
2215			continue;
2216
2217		super = (struct btrfs_super_block *)bh->b_data;
2218		if (btrfs_super_bytenr(super) != bytenr ||
2219		    strncmp((char *)(&super->magic), BTRFS_MAGIC,
2220			    sizeof(super->magic))) {
2221			brelse(bh);
2222			continue;
2223		}
2224
2225		if (!latest || btrfs_super_generation(super) > transid) {
2226			brelse(latest);
2227			latest = bh;
2228			transid = btrfs_super_generation(super);
2229		} else {
2230			brelse(bh);
2231		}
2232	}
2233	return latest;
 
2234}
2235
2236/*
2237 * this should be called twice, once with wait == 0 and
2238 * once with wait == 1.  When wait == 0 is done, all the buffer heads
2239 * we write are pinned.
2240 *
2241 * They are released when wait == 1 is done.
2242 * max_mirrors must be the same for both runs, and it indicates how
2243 * many supers on this one device should be written.
2244 *
2245 * max_mirrors == 0 means to write them all.
2246 */
2247static int write_dev_supers(struct btrfs_device *device,
2248			    struct btrfs_super_block *sb,
2249			    int do_barriers, int wait, int max_mirrors)
2250{
2251	struct buffer_head *bh;
 
 
2252	int i;
 
2253	int ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2254	int errors = 0;
2255	u32 crc;
 
2256	u64 bytenr;
2257	int last_barrier = 0;
2258
2259	if (max_mirrors == 0)
2260		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
2261
2262	/* make sure only the last submit_bh does a barrier */
2263	if (do_barriers) {
2264		for (i = 0; i < max_mirrors; i++) {
2265			bytenr = btrfs_sb_offset(i);
2266			if (bytenr + BTRFS_SUPER_INFO_SIZE >=
2267			    device->total_bytes)
2268				break;
2269			last_barrier = i;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2270		}
 
 
 
 
 
 
 
 
 
 
 
 
 
2271	}
2272
2273	for (i = 0; i < max_mirrors; i++) {
2274		bytenr = btrfs_sb_offset(i);
2275		if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->total_bytes)
2276			break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2277
2278		if (wait) {
2279			bh = __find_get_block(device->bdev, bytenr / 4096,
2280					      BTRFS_SUPER_INFO_SIZE);
2281			BUG_ON(!bh);
2282			wait_on_buffer(bh);
2283			if (!buffer_uptodate(bh))
2284				errors++;
 
 
 
 
2285
2286			/* drop our reference */
2287			brelse(bh);
2288
2289			/* drop the reference from the wait == 0 run */
2290			brelse(bh);
 
 
 
 
 
 
 
 
2291			continue;
2292		} else {
2293			btrfs_set_super_bytenr(sb, bytenr);
2294
2295			crc = ~(u32)0;
2296			crc = btrfs_csum_data(NULL, (char *)sb +
2297					      BTRFS_CSUM_SIZE, crc,
2298					      BTRFS_SUPER_INFO_SIZE -
2299					      BTRFS_CSUM_SIZE);
2300			btrfs_csum_final(crc, sb->csum);
 
 
 
 
2301
2302			/*
2303			 * one reference for us, and we leave it for the
2304			 * caller
2305			 */
2306			bh = __getblk(device->bdev, bytenr / 4096,
2307				      BTRFS_SUPER_INFO_SIZE);
2308			memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
2309
2310			/* one reference for submit_bh */
2311			get_bh(bh);
 
 
2312
2313			set_buffer_uptodate(bh);
2314			lock_buffer(bh);
2315			bh->b_end_io = btrfs_end_buffer_write_sync;
2316		}
 
2317
2318		if (i == last_barrier && do_barriers)
2319			ret = submit_bh(WRITE_FLUSH_FUA, bh);
2320		else
2321			ret = submit_bh(WRITE_SYNC, bh);
 
 
 
 
 
2322
2323		if (ret)
2324			errors++;
 
2325	}
2326	return errors < i ? 0 : -1;
 
2327}
2328
2329int write_all_supers(struct btrfs_root *root, int max_mirrors)
2330{
2331	struct list_head *head;
2332	struct btrfs_device *dev;
2333	struct btrfs_super_block *sb;
2334	struct btrfs_dev_item *dev_item;
2335	int ret;
2336	int do_barriers;
2337	int max_errors;
2338	int total_errors = 0;
2339	u64 flags;
2340
2341	max_errors = btrfs_super_num_devices(&root->fs_info->super_copy) - 1;
2342	do_barriers = !btrfs_test_opt(root, NOBARRIER);
2343
2344	sb = &root->fs_info->super_for_commit;
 
 
 
 
 
 
 
 
2345	dev_item = &sb->dev_item;
2346
2347	mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2348	head = &root->fs_info->fs_devices->devices;
2349	list_for_each_entry_rcu(dev, head, dev_list) {
 
 
 
 
 
 
 
 
 
 
 
 
 
2350		if (!dev->bdev) {
2351			total_errors++;
2352			continue;
2353		}
2354		if (!dev->in_fs_metadata || !dev->writeable)
 
2355			continue;
2356
2357		btrfs_set_stack_device_generation(dev_item, 0);
2358		btrfs_set_stack_device_type(dev_item, dev->type);
2359		btrfs_set_stack_device_id(dev_item, dev->devid);
2360		btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
2361		btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
 
 
2362		btrfs_set_stack_device_io_align(dev_item, dev->io_align);
2363		btrfs_set_stack_device_io_width(dev_item, dev->io_width);
2364		btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
2365		memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
2366		memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
 
2367
2368		flags = btrfs_super_flags(sb);
2369		btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
2370
2371		ret = write_dev_supers(dev, sb, do_barriers, 0, max_mirrors);
 
 
 
 
 
 
 
 
2372		if (ret)
2373			total_errors++;
2374	}
2375	if (total_errors > max_errors) {
2376		printk(KERN_ERR "btrfs: %d errors while writing supers\n",
2377		       total_errors);
2378		BUG();
 
 
 
 
 
 
2379	}
2380
2381	total_errors = 0;
2382	list_for_each_entry_rcu(dev, head, dev_list) {
2383		if (!dev->bdev)
2384			continue;
2385		if (!dev->in_fs_metadata || !dev->writeable)
 
2386			continue;
2387
2388		ret = write_dev_supers(dev, sb, do_barriers, 1, max_mirrors);
2389		if (ret)
2390			total_errors++;
2391	}
2392	mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2393	if (total_errors > max_errors) {
2394		printk(KERN_ERR "btrfs: %d errors while writing supers\n",
2395		       total_errors);
2396		BUG();
 
2397	}
2398	return 0;
2399}
2400
2401int write_ctree_super(struct btrfs_trans_handle *trans,
2402		      struct btrfs_root *root, int max_mirrors)
 
2403{
2404	int ret;
2405
2406	ret = write_all_supers(root, max_mirrors);
2407	return ret;
2408}
2409
2410int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
2411{
2412	spin_lock(&fs_info->fs_roots_radix_lock);
2413	radix_tree_delete(&fs_info->fs_roots_radix,
2414			  (unsigned long)root->root_key.objectid);
 
 
2415	spin_unlock(&fs_info->fs_roots_radix_lock);
2416
2417	if (btrfs_root_refs(&root->root_item) == 0)
2418		synchronize_srcu(&fs_info->subvol_srcu);
 
 
 
 
 
2419
2420	__btrfs_remove_free_space_cache(root->free_ino_pinned);
2421	__btrfs_remove_free_space_cache(root->free_ino_ctl);
2422	free_fs_root(root);
2423	return 0;
2424}
2425
2426static void free_fs_root(struct btrfs_root *root)
2427{
2428	iput(root->cache_inode);
2429	WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
2430	if (root->anon_dev)
2431		free_anon_bdev(root->anon_dev);
2432	free_extent_buffer(root->node);
2433	free_extent_buffer(root->commit_root);
2434	kfree(root->free_ino_ctl);
2435	kfree(root->free_ino_pinned);
2436	kfree(root->name);
2437	kfree(root);
2438}
2439
2440static int del_fs_roots(struct btrfs_fs_info *fs_info)
2441{
2442	int ret;
2443	struct btrfs_root *gang[8];
2444	int i;
2445
2446	while (!list_empty(&fs_info->dead_roots)) {
2447		gang[0] = list_entry(fs_info->dead_roots.next,
2448				     struct btrfs_root, root_list);
2449		list_del(&gang[0]->root_list);
2450
2451		if (gang[0]->in_radix) {
2452			btrfs_free_fs_root(fs_info, gang[0]);
2453		} else {
2454			free_extent_buffer(gang[0]->node);
2455			free_extent_buffer(gang[0]->commit_root);
2456			kfree(gang[0]);
2457		}
2458	}
2459
2460	while (1) {
2461		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2462					     (void **)gang, 0,
2463					     ARRAY_SIZE(gang));
2464		if (!ret)
2465			break;
2466		for (i = 0; i < ret; i++)
2467			btrfs_free_fs_root(fs_info, gang[i]);
2468	}
2469	return 0;
2470}
2471
2472int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
2473{
2474	u64 root_objectid = 0;
2475	struct btrfs_root *gang[8];
2476	int i;
2477	int ret;
 
 
2478
2479	while (1) {
2480		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2481					     (void **)gang, root_objectid,
2482					     ARRAY_SIZE(gang));
2483		if (!ret)
2484			break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2485
2486		root_objectid = gang[ret - 1]->root_key.objectid + 1;
2487		for (i = 0; i < ret; i++) {
2488			int err;
2489
2490			root_objectid = gang[i]->root_key.objectid;
2491			err = btrfs_orphan_cleanup(gang[i]);
2492			if (err)
2493				return err;
2494		}
2495		root_objectid++;
2496	}
2497	return 0;
2498}
2499
2500int btrfs_commit_super(struct btrfs_root *root)
2501{
2502	struct btrfs_trans_handle *trans;
2503	int ret;
2504
2505	mutex_lock(&root->fs_info->cleaner_mutex);
2506	btrfs_run_delayed_iputs(root);
2507	btrfs_clean_old_snapshots(root);
2508	mutex_unlock(&root->fs_info->cleaner_mutex);
2509
2510	/* wait until ongoing cleanup work done */
2511	down_write(&root->fs_info->cleanup_work_sem);
2512	up_write(&root->fs_info->cleanup_work_sem);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2513
2514	trans = btrfs_join_transaction(root);
2515	if (IS_ERR(trans))
2516		return PTR_ERR(trans);
2517	ret = btrfs_commit_transaction(trans, root);
2518	BUG_ON(ret);
2519	/* run commit again to drop the original snapshot */
2520	trans = btrfs_join_transaction(root);
2521	if (IS_ERR(trans))
2522		return PTR_ERR(trans);
2523	btrfs_commit_transaction(trans, root);
2524	ret = btrfs_write_and_wait_transaction(NULL, root);
2525	BUG_ON(ret);
2526
2527	ret = write_ctree_super(NULL, root, 0);
2528	return ret;
2529}
 
2530
2531int close_ctree(struct btrfs_root *root)
2532{
2533	struct btrfs_fs_info *fs_info = root->fs_info;
2534	int ret;
2535
2536	fs_info->closing = 1;
2537	smp_mb();
2538
2539	btrfs_scrub_cancel(root);
2540
2541	/* wait for any defraggers to finish */
2542	wait_event(fs_info->transaction_wait,
2543		   (atomic_read(&fs_info->defrag_running) == 0));
2544
2545	/* clear out the rbtree of defraggable inodes */
2546	btrfs_run_defrag_inodes(root->fs_info);
2547
2548	btrfs_put_block_group_cache(fs_info);
2549
2550	/*
2551	 * Here come 2 situations when btrfs is broken to flip readonly:
 
 
 
 
 
 
2552	 *
2553	 * 1. when btrfs flips readonly somewhere else before
2554	 * btrfs_commit_super, sb->s_flags has MS_RDONLY flag,
2555	 * and btrfs will skip to write sb directly to keep
2556	 * ERROR state on disk.
2557	 *
2558	 * 2. when btrfs flips readonly just in btrfs_commit_super,
2559	 * and in such case, btrfs cannot write sb via btrfs_commit_super,
2560	 * and since fs_state has been set BTRFS_SUPER_FLAG_ERROR flag,
2561	 * btrfs will cleanup all FS resources first and write sb then.
 
2562	 */
2563	if (!(fs_info->sb->s_flags & MS_RDONLY)) {
2564		ret = btrfs_commit_super(root);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2565		if (ret)
2566			printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
2567	}
2568
2569	if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
2570		ret = btrfs_error_commit_super(root);
2571		if (ret)
2572			printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
2573	}
2574
2575	kthread_stop(root->fs_info->transaction_kthread);
2576	kthread_stop(root->fs_info->cleaner_kthread);
2577
2578	fs_info->closing = 2;
2579	smp_mb();
2580
2581	if (fs_info->delalloc_bytes) {
2582		printk(KERN_INFO "btrfs: at unmount delalloc count %llu\n",
2583		       (unsigned long long)fs_info->delalloc_bytes);
2584	}
2585	if (fs_info->total_ref_cache_size) {
2586		printk(KERN_INFO "btrfs: at umount reference cache size %llu\n",
2587		       (unsigned long long)fs_info->total_ref_cache_size);
2588	}
2589
2590	free_extent_buffer(fs_info->extent_root->node);
2591	free_extent_buffer(fs_info->extent_root->commit_root);
2592	free_extent_buffer(fs_info->tree_root->node);
2593	free_extent_buffer(fs_info->tree_root->commit_root);
2594	free_extent_buffer(root->fs_info->chunk_root->node);
2595	free_extent_buffer(root->fs_info->chunk_root->commit_root);
2596	free_extent_buffer(root->fs_info->dev_root->node);
2597	free_extent_buffer(root->fs_info->dev_root->commit_root);
2598	free_extent_buffer(root->fs_info->csum_root->node);
2599	free_extent_buffer(root->fs_info->csum_root->commit_root);
2600
2601	btrfs_free_block_groups(root->fs_info);
 
 
 
2602
2603	del_fs_roots(fs_info);
 
 
2604
2605	iput(fs_info->btree_inode);
2606	kfree(fs_info->delayed_root);
2607
2608	btrfs_stop_workers(&fs_info->generic_worker);
2609	btrfs_stop_workers(&fs_info->fixup_workers);
2610	btrfs_stop_workers(&fs_info->delalloc_workers);
2611	btrfs_stop_workers(&fs_info->workers);
2612	btrfs_stop_workers(&fs_info->endio_workers);
2613	btrfs_stop_workers(&fs_info->endio_meta_workers);
2614	btrfs_stop_workers(&fs_info->endio_meta_write_workers);
2615	btrfs_stop_workers(&fs_info->endio_write_workers);
2616	btrfs_stop_workers(&fs_info->endio_freespace_worker);
2617	btrfs_stop_workers(&fs_info->submit_workers);
2618	btrfs_stop_workers(&fs_info->delayed_workers);
2619	btrfs_stop_workers(&fs_info->caching_workers);
2620
2621	btrfs_close_devices(fs_info->fs_devices);
2622	btrfs_mapping_tree_free(&fs_info->mapping_tree);
 
 
 
 
2623
2624	bdi_destroy(&fs_info->bdi);
2625	cleanup_srcu_struct(&fs_info->subvol_srcu);
2626
2627	kfree(fs_info->extent_root);
2628	kfree(fs_info->tree_root);
2629	kfree(fs_info->chunk_root);
2630	kfree(fs_info->dev_root);
2631	kfree(fs_info->csum_root);
2632	kfree(fs_info);
2633
2634	return 0;
2635}
 
 
 
 
 
 
2636
2637int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
2638{
2639	int ret;
2640	struct inode *btree_inode = buf->first_page->mapping->host;
2641
2642	ret = extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf,
2643				     NULL);
2644	if (!ret)
2645		return ret;
2646
2647	ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
2648				    parent_transid);
2649	return !ret;
2650}
2651
2652int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
2653{
2654	struct inode *btree_inode = buf->first_page->mapping->host;
2655	return set_extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree,
2656					  buf);
2657}
2658
2659void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
 
2660{
2661	struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
2662	u64 transid = btrfs_header_generation(buf);
2663	struct inode *btree_inode = root->fs_info->btree_inode;
2664	int was_dirty;
2665
2666	btrfs_assert_tree_locked(buf);
2667	if (transid != root->fs_info->generation) {
2668		printk(KERN_CRIT "btrfs transid mismatch buffer %llu, "
2669		       "found %llu running %llu\n",
2670			(unsigned long long)buf->start,
2671			(unsigned long long)transid,
2672			(unsigned long long)root->fs_info->generation);
2673		WARN_ON(1);
2674	}
2675	was_dirty = set_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
2676					    buf);
2677	if (!was_dirty) {
2678		spin_lock(&root->fs_info->delalloc_lock);
2679		root->fs_info->dirty_metadata_bytes += buf->len;
2680		spin_unlock(&root->fs_info->delalloc_lock);
2681	}
2682}
2683
2684void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
2685{
2686	/*
2687	 * looks as though older kernels can get into trouble with
2688	 * this code, they end up stuck in balance_dirty_pages forever
 
2689	 */
2690	u64 num_dirty;
2691	unsigned long thresh = 32 * 1024 * 1024;
2692
2693	if (current->flags & PF_MEMALLOC)
2694		return;
2695
2696	btrfs_balance_delayed_items(root);
2697
2698	num_dirty = root->fs_info->dirty_metadata_bytes;
2699
2700	if (num_dirty > thresh) {
2701		balance_dirty_pages_ratelimited_nr(
2702				   root->fs_info->btree_inode->i_mapping, 1);
 
2703	}
2704	return;
2705}
2706
2707void __btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
 
2708{
2709	/*
2710	 * looks as though older kernels can get into trouble with
2711	 * this code, they end up stuck in balance_dirty_pages forever
2712	 */
2713	u64 num_dirty;
2714	unsigned long thresh = 32 * 1024 * 1024;
2715
2716	if (current->flags & PF_MEMALLOC)
2717		return;
2718
2719	num_dirty = root->fs_info->dirty_metadata_bytes;
 
2720
2721	if (num_dirty > thresh) {
2722		balance_dirty_pages_ratelimited_nr(
2723				   root->fs_info->btree_inode->i_mapping, 1);
 
 
2724	}
2725	return;
2726}
2727
2728int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
2729{
2730	struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
2731	int ret;
2732	ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
2733	if (ret == 0)
2734		set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
2735	return ret;
2736}
2737
2738int btree_lock_page_hook(struct page *page)
2739{
2740	struct inode *inode = page->mapping->host;
2741	struct btrfs_root *root = BTRFS_I(inode)->root;
2742	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2743	struct extent_buffer *eb;
2744	unsigned long len;
2745	u64 bytenr = page_offset(page);
2746
2747	if (page->private == EXTENT_PAGE_PRIVATE)
2748		goto out;
2749
2750	len = page->private >> 2;
2751	eb = find_extent_buffer(io_tree, bytenr, len);
2752	if (!eb)
2753		goto out;
2754
2755	btrfs_tree_lock(eb);
2756	btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
2757
2758	if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
2759		spin_lock(&root->fs_info->delalloc_lock);
2760		if (root->fs_info->dirty_metadata_bytes >= eb->len)
2761			root->fs_info->dirty_metadata_bytes -= eb->len;
2762		else
2763			WARN_ON(1);
2764		spin_unlock(&root->fs_info->delalloc_lock);
2765	}
2766
2767	btrfs_tree_unlock(eb);
2768	free_extent_buffer(eb);
2769out:
2770	lock_page(page);
2771	return 0;
2772}
2773
2774static void btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
2775			      int read_only)
2776{
2777	if (read_only)
2778		return;
2779
2780	if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)
2781		printk(KERN_WARNING "warning: mount fs with errors, "
2782		       "running btrfsck is recommended\n");
2783}
2784
2785int btrfs_error_commit_super(struct btrfs_root *root)
2786{
2787	int ret;
2788
2789	mutex_lock(&root->fs_info->cleaner_mutex);
2790	btrfs_run_delayed_iputs(root);
2791	mutex_unlock(&root->fs_info->cleaner_mutex);
2792
2793	down_write(&root->fs_info->cleanup_work_sem);
2794	up_write(&root->fs_info->cleanup_work_sem);
2795
2796	/* cleanup FS via transaction */
2797	btrfs_cleanup_transaction(root);
2798
2799	ret = write_ctree_super(NULL, root, 0);
 
 
2800
2801	return ret;
 
2802}
2803
2804static int btrfs_destroy_ordered_operations(struct btrfs_root *root)
2805{
2806	struct btrfs_inode *btrfs_inode;
2807	struct list_head splice;
 
2808
2809	INIT_LIST_HEAD(&splice);
 
 
 
 
2810
2811	mutex_lock(&root->fs_info->ordered_operations_mutex);
2812	spin_lock(&root->fs_info->ordered_extent_lock);
 
2813
2814	list_splice_init(&root->fs_info->ordered_operations, &splice);
2815	while (!list_empty(&splice)) {
2816		btrfs_inode = list_entry(splice.next, struct btrfs_inode,
2817					 ordered_operations);
2818
2819		list_del_init(&btrfs_inode->ordered_operations);
2820
2821		btrfs_invalidate_inodes(btrfs_inode->root);
 
2822	}
2823
2824	spin_unlock(&root->fs_info->ordered_extent_lock);
2825	mutex_unlock(&root->fs_info->ordered_operations_mutex);
2826
2827	return 0;
2828}
2829
2830static int btrfs_destroy_ordered_extents(struct btrfs_root *root)
2831{
2832	struct list_head splice;
2833	struct btrfs_ordered_extent *ordered;
2834	struct inode *inode;
2835
2836	INIT_LIST_HEAD(&splice);
 
 
 
 
 
 
 
 
 
2837
2838	spin_lock(&root->fs_info->ordered_extent_lock);
 
 
 
2839
2840	list_splice_init(&root->fs_info->ordered_extents, &splice);
 
2841	while (!list_empty(&splice)) {
2842		ordered = list_entry(splice.next, struct btrfs_ordered_extent,
2843				     root_extent_list);
 
 
2844
2845		list_del_init(&ordered->root_extent_list);
2846		atomic_inc(&ordered->refs);
2847
2848		/* the inode may be getting freed (in sys_unlink path). */
2849		inode = igrab(ordered->inode);
2850
2851		spin_unlock(&root->fs_info->ordered_extent_lock);
2852		if (inode)
2853			iput(inode);
2854
2855		atomic_set(&ordered->refs, 1);
2856		btrfs_put_ordered_extent(ordered);
2857
2858		spin_lock(&root->fs_info->ordered_extent_lock);
2859	}
 
2860
2861	spin_unlock(&root->fs_info->ordered_extent_lock);
2862
2863	return 0;
 
 
 
 
2864}
2865
2866static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
2867				      struct btrfs_root *root)
2868{
2869	struct rb_node *node;
2870	struct btrfs_delayed_ref_root *delayed_refs;
2871	struct btrfs_delayed_ref_node *ref;
2872	int ret = 0;
2873
2874	delayed_refs = &trans->delayed_refs;
2875
2876	spin_lock(&delayed_refs->lock);
2877	if (delayed_refs->num_entries == 0) {
2878		spin_unlock(&delayed_refs->lock);
2879		printk(KERN_INFO "delayed_refs has NO entry\n");
2880		return ret;
2881	}
2882
2883	node = rb_first(&delayed_refs->root);
2884	while (node) {
2885		ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2886		node = rb_next(node);
2887
2888		ref->in_tree = 0;
2889		rb_erase(&ref->rb_node, &delayed_refs->root);
2890		delayed_refs->num_entries--;
2891
2892		atomic_set(&ref->refs, 1);
2893		if (btrfs_delayed_ref_is_head(ref)) {
2894			struct btrfs_delayed_ref_head *head;
2895
2896			head = btrfs_delayed_node_to_head(ref);
2897			mutex_lock(&head->mutex);
2898			kfree(head->extent_op);
2899			delayed_refs->num_heads--;
2900			if (list_empty(&head->cluster))
2901				delayed_refs->num_heads_ready--;
2902			list_del_init(&head->cluster);
2903			mutex_unlock(&head->mutex);
2904		}
 
 
 
 
 
 
 
 
 
 
2905
2906		spin_unlock(&delayed_refs->lock);
2907		btrfs_put_delayed_ref(ref);
 
 
 
 
 
 
 
 
 
 
 
 
2908
 
 
 
 
 
2909		cond_resched();
2910		spin_lock(&delayed_refs->lock);
2911	}
 
2912
2913	spin_unlock(&delayed_refs->lock);
2914
2915	return ret;
2916}
2917
2918static int btrfs_destroy_pending_snapshots(struct btrfs_transaction *t)
2919{
2920	struct btrfs_pending_snapshot *snapshot;
2921	struct list_head splice;
2922
2923	INIT_LIST_HEAD(&splice);
2924
2925	list_splice_init(&t->pending_snapshots, &splice);
2926
2927	while (!list_empty(&splice)) {
2928		snapshot = list_entry(splice.next,
2929				      struct btrfs_pending_snapshot,
2930				      list);
 
 
2931
2932		list_del_init(&snapshot->list);
2933
2934		kfree(snapshot);
 
 
 
 
 
 
 
 
 
 
 
2935	}
2936
2937	return 0;
2938}
2939
2940static int btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
2941{
2942	struct btrfs_inode *btrfs_inode;
2943	struct list_head splice;
2944
2945	INIT_LIST_HEAD(&splice);
2946
2947	spin_lock(&root->fs_info->delalloc_lock);
2948	list_splice_init(&root->fs_info->delalloc_inodes, &splice);
2949
 
 
2950	while (!list_empty(&splice)) {
2951		btrfs_inode = list_entry(splice.next, struct btrfs_inode,
2952				    delalloc_inodes);
 
 
 
2953
2954		list_del_init(&btrfs_inode->delalloc_inodes);
 
2955
2956		btrfs_invalidate_inodes(btrfs_inode->root);
2957	}
2958
2959	spin_unlock(&root->fs_info->delalloc_lock);
2960
2961	return 0;
2962}
2963
2964static int btrfs_destroy_marked_extents(struct btrfs_root *root,
2965					struct extent_io_tree *dirty_pages,
2966					int mark)
2967{
2968	int ret;
2969	struct page *page;
2970	struct inode *btree_inode = root->fs_info->btree_inode;
2971	struct extent_buffer *eb;
2972	u64 start = 0;
2973	u64 end;
2974	u64 offset;
2975	unsigned long index;
2976
2977	while (1) {
2978		ret = find_first_extent_bit(dirty_pages, start, &start, &end,
2979					    mark);
2980		if (ret)
2981			break;
2982
2983		clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS);
2984		while (start <= end) {
2985			index = start >> PAGE_CACHE_SHIFT;
2986			start = (u64)(index + 1) << PAGE_CACHE_SHIFT;
2987			page = find_get_page(btree_inode->i_mapping, index);
2988			if (!page)
2989				continue;
2990			offset = page_offset(page);
2991
2992			spin_lock(&dirty_pages->buffer_lock);
2993			eb = radix_tree_lookup(
2994			     &(&BTRFS_I(page->mapping->host)->io_tree)->buffer,
2995					       offset >> PAGE_CACHE_SHIFT);
2996			spin_unlock(&dirty_pages->buffer_lock);
2997			if (eb) {
2998				ret = test_and_clear_bit(EXTENT_BUFFER_DIRTY,
2999							 &eb->bflags);
3000				atomic_set(&eb->refs, 1);
3001			}
3002			if (PageWriteback(page))
3003				end_page_writeback(page);
3004
3005			lock_page(page);
3006			if (PageDirty(page)) {
3007				clear_page_dirty_for_io(page);
3008				spin_lock_irq(&page->mapping->tree_lock);
3009				radix_tree_tag_clear(&page->mapping->page_tree,
3010							page_index(page),
3011							PAGECACHE_TAG_DIRTY);
3012				spin_unlock_irq(&page->mapping->tree_lock);
3013			}
3014
3015			page->mapping->a_ops->invalidatepage(page, 0);
3016			unlock_page(page);
3017		}
3018	}
3019
3020	return ret;
3021}
3022
3023static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
3024				       struct extent_io_tree *pinned_extents)
3025{
3026	struct extent_io_tree *unpin;
3027	u64 start;
3028	u64 end;
3029	int ret;
3030
3031	unpin = pinned_extents;
3032	while (1) {
3033		ret = find_first_extent_bit(unpin, 0, &start, &end,
3034					    EXTENT_DIRTY);
3035		if (ret)
 
 
 
 
 
 
 
 
 
3036			break;
 
3037
3038		/* opt_discard */
3039		if (btrfs_test_opt(root, DISCARD))
3040			ret = btrfs_error_discard_extent(root, start,
3041							 end + 1 - start,
3042							 NULL);
3043
3044		clear_extent_dirty(unpin, start, end, GFP_NOFS);
3045		btrfs_error_unpin_extent_range(root, start, end);
3046		cond_resched();
3047	}
 
 
 
 
 
3048
3049	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
3050}
3051
3052static int btrfs_cleanup_transaction(struct btrfs_root *root)
 
3053{
3054	struct btrfs_transaction *t;
3055	LIST_HEAD(list);
 
 
 
 
 
 
 
 
 
 
 
 
3056
3057	WARN_ON(1);
 
 
 
 
 
 
 
 
 
 
3058
3059	mutex_lock(&root->fs_info->transaction_kthread_mutex);
 
 
 
 
 
 
 
3060
3061	spin_lock(&root->fs_info->trans_lock);
3062	list_splice_init(&root->fs_info->trans_list, &list);
3063	root->fs_info->trans_no_join = 1;
3064	spin_unlock(&root->fs_info->trans_lock);
 
 
 
3065
3066	while (!list_empty(&list)) {
3067		t = list_entry(list.next, struct btrfs_transaction, list);
3068		if (!t)
 
 
 
 
 
 
 
 
 
 
3069			break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3070
3071		btrfs_destroy_ordered_operations(root);
 
3072
3073		btrfs_destroy_ordered_extents(root);
 
3074
3075		btrfs_destroy_delayed_refs(t, root);
3076
3077		btrfs_block_rsv_release(root,
3078					&root->fs_info->trans_block_rsv,
3079					t->dirty_pages.dirty_bytes);
3080
3081		/* FIXME: cleanup wait for commit */
3082		t->in_commit = 1;
3083		t->blocked = 1;
3084		if (waitqueue_active(&root->fs_info->transaction_blocked_wait))
3085			wake_up(&root->fs_info->transaction_blocked_wait);
3086
3087		t->blocked = 0;
3088		if (waitqueue_active(&root->fs_info->transaction_wait))
3089			wake_up(&root->fs_info->transaction_wait);
3090
3091		t->commit_done = 1;
3092		if (waitqueue_active(&t->commit_wait))
3093			wake_up(&t->commit_wait);
3094
3095		btrfs_destroy_pending_snapshots(t);
3096
3097		btrfs_destroy_delalloc_inodes(root);
 
 
3098
3099		spin_lock(&root->fs_info->trans_lock);
3100		root->fs_info->running_transaction = NULL;
3101		spin_unlock(&root->fs_info->trans_lock);
3102
3103		btrfs_destroy_marked_extents(root, &t->dirty_pages,
3104					     EXTENT_DIRTY);
3105
3106		btrfs_destroy_pinned_extent(root,
3107					    root->fs_info->pinned_extents);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3108
3109		atomic_set(&t->use_count, 0);
 
 
3110		list_del_init(&t->list);
3111		memset(t, 0, sizeof(*t));
3112		kmem_cache_free(btrfs_transaction_cachep, t);
3113	}
3114
3115	spin_lock(&root->fs_info->trans_lock);
3116	root->fs_info->trans_no_join = 0;
3117	spin_unlock(&root->fs_info->trans_lock);
3118	mutex_unlock(&root->fs_info->transaction_kthread_mutex);
 
 
 
 
 
 
 
3119
3120	return 0;
3121}
3122
3123static struct extent_io_ops btree_extent_io_ops = {
3124	.write_cache_pages_lock_hook = btree_lock_page_hook,
3125	.readpage_end_io_hook = btree_readpage_end_io_hook,
3126	.submit_bio_hook = btree_submit_bio_hook,
3127	/* note we're sharing with inode.c for the merge bio hook */
3128	.merge_bio_hook = btrfs_merge_bio_hook,
3129};