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v5.4
   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/buffer_head.h>
  11#include <linux/workqueue.h>
  12#include <linux/kthread.h>
  13#include <linux/slab.h>
  14#include <linux/migrate.h>
  15#include <linux/ratelimit.h>
  16#include <linux/uuid.h>
  17#include <linux/semaphore.h>
  18#include <linux/error-injection.h>
  19#include <linux/crc32c.h>
  20#include <linux/sched/mm.h>
  21#include <asm/unaligned.h>
  22#include <crypto/hash.h>
  23#include "ctree.h"
  24#include "disk-io.h"
  25#include "transaction.h"
  26#include "btrfs_inode.h"
  27#include "volumes.h"
  28#include "print-tree.h"
  29#include "locking.h"
  30#include "tree-log.h"
  31#include "free-space-cache.h"
  32#include "free-space-tree.h"
  33#include "inode-map.h"
  34#include "check-integrity.h"
  35#include "rcu-string.h"
  36#include "dev-replace.h"
  37#include "raid56.h"
  38#include "sysfs.h"
  39#include "qgroup.h"
  40#include "compression.h"
  41#include "tree-checker.h"
  42#include "ref-verify.h"
  43#include "block-group.h"
 
 
 
 
 
 
 
 
 
 
 
 
 
  44
  45#define BTRFS_SUPER_FLAG_SUPP	(BTRFS_HEADER_FLAG_WRITTEN |\
  46				 BTRFS_HEADER_FLAG_RELOC |\
  47				 BTRFS_SUPER_FLAG_ERROR |\
  48				 BTRFS_SUPER_FLAG_SEEDING |\
  49				 BTRFS_SUPER_FLAG_METADUMP |\
  50				 BTRFS_SUPER_FLAG_METADUMP_V2)
  51
  52static const struct extent_io_ops btree_extent_io_ops;
  53static void end_workqueue_fn(struct btrfs_work *work);
  54static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
  55static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
  56				      struct btrfs_fs_info *fs_info);
  57static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
  58static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
  59					struct extent_io_tree *dirty_pages,
  60					int mark);
  61static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
  62				       struct extent_io_tree *pinned_extents);
  63static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info);
  64static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info);
  65
  66/*
  67 * btrfs_end_io_wq structs are used to do processing in task context when an IO
  68 * is complete.  This is used during reads to verify checksums, and it is used
  69 * by writes to insert metadata for new file extents after IO is complete.
  70 */
  71struct btrfs_end_io_wq {
  72	struct bio *bio;
  73	bio_end_io_t *end_io;
  74	void *private;
  75	struct btrfs_fs_info *info;
  76	blk_status_t status;
  77	enum btrfs_wq_endio_type metadata;
  78	struct btrfs_work work;
  79};
  80
  81static struct kmem_cache *btrfs_end_io_wq_cache;
  82
  83int __init btrfs_end_io_wq_init(void)
  84{
  85	btrfs_end_io_wq_cache = kmem_cache_create("btrfs_end_io_wq",
  86					sizeof(struct btrfs_end_io_wq),
  87					0,
  88					SLAB_MEM_SPREAD,
  89					NULL);
  90	if (!btrfs_end_io_wq_cache)
  91		return -ENOMEM;
  92	return 0;
  93}
  94
  95void __cold btrfs_end_io_wq_exit(void)
  96{
  97	kmem_cache_destroy(btrfs_end_io_wq_cache);
 
  98}
  99
 100/*
 101 * async submit bios are used to offload expensive checksumming
 102 * onto the worker threads.  They checksum file and metadata bios
 103 * just before they are sent down the IO stack.
 104 */
 105struct async_submit_bio {
 106	void *private_data;
 107	struct bio *bio;
 108	extent_submit_bio_start_t *submit_bio_start;
 109	int mirror_num;
 110	/*
 111	 * bio_offset is optional, can be used if the pages in the bio
 112	 * can't tell us where in the file the bio should go
 113	 */
 114	u64 bio_offset;
 115	struct btrfs_work work;
 116	blk_status_t status;
 117};
 118
 119/*
 120 * Lockdep class keys for extent_buffer->lock's in this root.  For a given
 121 * eb, the lockdep key is determined by the btrfs_root it belongs to and
 122 * the level the eb occupies in the tree.
 123 *
 124 * Different roots are used for different purposes and may nest inside each
 125 * other and they require separate keysets.  As lockdep keys should be
 126 * static, assign keysets according to the purpose of the root as indicated
 127 * by btrfs_root->root_key.objectid.  This ensures that all special purpose
 128 * roots have separate keysets.
 129 *
 130 * Lock-nesting across peer nodes is always done with the immediate parent
 131 * node locked thus preventing deadlock.  As lockdep doesn't know this, use
 132 * subclass to avoid triggering lockdep warning in such cases.
 133 *
 134 * The key is set by the readpage_end_io_hook after the buffer has passed
 135 * csum validation but before the pages are unlocked.  It is also set by
 136 * btrfs_init_new_buffer on freshly allocated blocks.
 137 *
 138 * We also add a check to make sure the highest level of the tree is the
 139 * same as our lockdep setup here.  If BTRFS_MAX_LEVEL changes, this code
 140 * needs update as well.
 141 */
 142#ifdef CONFIG_DEBUG_LOCK_ALLOC
 143# if BTRFS_MAX_LEVEL != 8
 144#  error
 145# endif
 146
 147static struct btrfs_lockdep_keyset {
 148	u64			id;		/* root objectid */
 149	const char		*name_stem;	/* lock name stem */
 150	char			names[BTRFS_MAX_LEVEL + 1][20];
 151	struct lock_class_key	keys[BTRFS_MAX_LEVEL + 1];
 152} btrfs_lockdep_keysets[] = {
 153	{ .id = BTRFS_ROOT_TREE_OBJECTID,	.name_stem = "root"	},
 154	{ .id = BTRFS_EXTENT_TREE_OBJECTID,	.name_stem = "extent"	},
 155	{ .id = BTRFS_CHUNK_TREE_OBJECTID,	.name_stem = "chunk"	},
 156	{ .id = BTRFS_DEV_TREE_OBJECTID,	.name_stem = "dev"	},
 157	{ .id = BTRFS_FS_TREE_OBJECTID,		.name_stem = "fs"	},
 158	{ .id = BTRFS_CSUM_TREE_OBJECTID,	.name_stem = "csum"	},
 159	{ .id = BTRFS_QUOTA_TREE_OBJECTID,	.name_stem = "quota"	},
 160	{ .id = BTRFS_TREE_LOG_OBJECTID,	.name_stem = "log"	},
 161	{ .id = BTRFS_TREE_RELOC_OBJECTID,	.name_stem = "treloc"	},
 162	{ .id = BTRFS_DATA_RELOC_TREE_OBJECTID,	.name_stem = "dreloc"	},
 163	{ .id = BTRFS_UUID_TREE_OBJECTID,	.name_stem = "uuid"	},
 164	{ .id = BTRFS_FREE_SPACE_TREE_OBJECTID,	.name_stem = "free-space" },
 165	{ .id = 0,				.name_stem = "tree"	},
 166};
 167
 168void __init btrfs_init_lockdep(void)
 169{
 170	int i, j;
 171
 172	/* initialize lockdep class names */
 173	for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) {
 174		struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i];
 175
 176		for (j = 0; j < ARRAY_SIZE(ks->names); j++)
 177			snprintf(ks->names[j], sizeof(ks->names[j]),
 178				 "btrfs-%s-%02d", ks->name_stem, j);
 179	}
 180}
 181
 182void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
 183				    int level)
 184{
 185	struct btrfs_lockdep_keyset *ks;
 186
 187	BUG_ON(level >= ARRAY_SIZE(ks->keys));
 188
 189	/* find the matching keyset, id 0 is the default entry */
 190	for (ks = btrfs_lockdep_keysets; ks->id; ks++)
 191		if (ks->id == objectid)
 192			break;
 193
 194	lockdep_set_class_and_name(&eb->lock,
 195				   &ks->keys[level], ks->names[level]);
 196}
 197
 198#endif
 199
 200/*
 201 * extents on the btree inode are pretty simple, there's one extent
 202 * that covers the entire device
 203 */
 204struct extent_map *btree_get_extent(struct btrfs_inode *inode,
 205		struct page *page, size_t pg_offset, u64 start, u64 len,
 206		int create)
 207{
 208	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 209	struct extent_map_tree *em_tree = &inode->extent_tree;
 210	struct extent_map *em;
 211	int ret;
 212
 213	read_lock(&em_tree->lock);
 214	em = lookup_extent_mapping(em_tree, start, len);
 215	if (em) {
 216		em->bdev = fs_info->fs_devices->latest_bdev;
 217		read_unlock(&em_tree->lock);
 218		goto out;
 219	}
 220	read_unlock(&em_tree->lock);
 221
 222	em = alloc_extent_map();
 223	if (!em) {
 224		em = ERR_PTR(-ENOMEM);
 225		goto out;
 226	}
 227	em->start = 0;
 228	em->len = (u64)-1;
 229	em->block_len = (u64)-1;
 230	em->block_start = 0;
 231	em->bdev = fs_info->fs_devices->latest_bdev;
 232
 233	write_lock(&em_tree->lock);
 234	ret = add_extent_mapping(em_tree, em, 0);
 235	if (ret == -EEXIST) {
 236		free_extent_map(em);
 237		em = lookup_extent_mapping(em_tree, start, len);
 238		if (!em)
 239			em = ERR_PTR(-EIO);
 240	} else if (ret) {
 241		free_extent_map(em);
 242		em = ERR_PTR(ret);
 243	}
 244	write_unlock(&em_tree->lock);
 245
 246out:
 247	return em;
 248}
 249
 250/*
 251 * Compute the csum of a btree block and store the result to provided buffer.
 252 *
 253 * Returns error if the extent buffer cannot be mapped.
 254 */
 255static int csum_tree_block(struct extent_buffer *buf, u8 *result)
 256{
 257	struct btrfs_fs_info *fs_info = buf->fs_info;
 
 
 258	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 259	unsigned long len;
 260	unsigned long cur_len;
 261	unsigned long offset = BTRFS_CSUM_SIZE;
 262	char *kaddr;
 263	unsigned long map_start;
 264	unsigned long map_len;
 265	int err;
 266
 267	shash->tfm = fs_info->csum_shash;
 268	crypto_shash_init(shash);
 269
 270	len = buf->len - offset;
 271
 272	while (len > 0) {
 273		/*
 274		 * Note: we don't need to check for the err == 1 case here, as
 275		 * with the given combination of 'start = BTRFS_CSUM_SIZE (32)'
 276		 * and 'min_len = 32' and the currently implemented mapping
 277		 * algorithm we cannot cross a page boundary.
 278		 */
 279		err = map_private_extent_buffer(buf, offset, 32,
 280					&kaddr, &map_start, &map_len);
 281		if (WARN_ON(err))
 282			return err;
 283		cur_len = min(len, map_len - (offset - map_start));
 284		crypto_shash_update(shash, kaddr + offset - map_start, cur_len);
 285		len -= cur_len;
 286		offset += cur_len;
 287	}
 288	memset(result, 0, BTRFS_CSUM_SIZE);
 289
 290	crypto_shash_final(shash, result);
 291
 292	return 0;
 293}
 294
 295/*
 296 * we can't consider a given block up to date unless the transid of the
 297 * block matches the transid in the parent node's pointer.  This is how we
 298 * detect blocks that either didn't get written at all or got written
 299 * in the wrong place.
 300 */
 301static int verify_parent_transid(struct extent_io_tree *io_tree,
 302				 struct extent_buffer *eb, u64 parent_transid,
 303				 int atomic)
 304{
 305	struct extent_state *cached_state = NULL;
 306	int ret;
 307	bool need_lock = (current->journal_info == BTRFS_SEND_TRANS_STUB);
 308
 309	if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 310		return 0;
 311
 312	if (atomic)
 313		return -EAGAIN;
 314
 315	if (need_lock) {
 316		btrfs_tree_read_lock(eb);
 317		btrfs_set_lock_blocking_read(eb);
 318	}
 319
 320	lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
 321			 &cached_state);
 322	if (extent_buffer_uptodate(eb) &&
 323	    btrfs_header_generation(eb) == parent_transid) {
 324		ret = 0;
 325		goto out;
 326	}
 327	btrfs_err_rl(eb->fs_info,
 328		"parent transid verify failed on %llu wanted %llu found %llu",
 329			eb->start,
 330			parent_transid, btrfs_header_generation(eb));
 331	ret = 1;
 332
 333	/*
 334	 * Things reading via commit roots that don't have normal protection,
 335	 * like send, can have a really old block in cache that may point at a
 336	 * block that has been freed and re-allocated.  So don't clear uptodate
 337	 * if we find an eb that is under IO (dirty/writeback) because we could
 338	 * end up reading in the stale data and then writing it back out and
 339	 * making everybody very sad.
 340	 */
 341	if (!extent_buffer_under_io(eb))
 342		clear_extent_buffer_uptodate(eb);
 343out:
 344	unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
 345			     &cached_state);
 346	if (need_lock)
 347		btrfs_tree_read_unlock_blocking(eb);
 348	return ret;
 349}
 350
 351static bool btrfs_supported_super_csum(u16 csum_type)
 352{
 353	switch (csum_type) {
 354	case BTRFS_CSUM_TYPE_CRC32:
 
 
 
 355		return true;
 356	default:
 357		return false;
 358	}
 359}
 360
 361/*
 362 * Return 0 if the superblock checksum type matches the checksum value of that
 363 * algorithm. Pass the raw disk superblock data.
 364 */
 365static int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
 366				  char *raw_disk_sb)
 367{
 368	struct btrfs_super_block *disk_sb =
 369		(struct btrfs_super_block *)raw_disk_sb;
 370	char result[BTRFS_CSUM_SIZE];
 371	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 372
 373	shash->tfm = fs_info->csum_shash;
 374	crypto_shash_init(shash);
 375
 376	/*
 377	 * The super_block structure does not span the whole
 378	 * BTRFS_SUPER_INFO_SIZE range, we expect that the unused space is
 379	 * filled with zeros and is included in the checksum.
 380	 */
 381	crypto_shash_update(shash, raw_disk_sb + BTRFS_CSUM_SIZE,
 382			    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
 383	crypto_shash_final(shash, result);
 384
 385	if (memcmp(disk_sb->csum, result, btrfs_super_csum_size(disk_sb)))
 386		return 1;
 387
 388	return 0;
 389}
 390
 391int btrfs_verify_level_key(struct extent_buffer *eb, int level,
 392			   struct btrfs_key *first_key, u64 parent_transid)
 393{
 394	struct btrfs_fs_info *fs_info = eb->fs_info;
 395	int found_level;
 396	struct btrfs_key found_key;
 397	int ret;
 398
 399	found_level = btrfs_header_level(eb);
 400	if (found_level != level) {
 401		WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
 402		     KERN_ERR "BTRFS: tree level check failed\n");
 403		btrfs_err(fs_info,
 404"tree level mismatch detected, bytenr=%llu level expected=%u has=%u",
 405			  eb->start, level, found_level);
 406		return -EIO;
 407	}
 408
 409	if (!first_key)
 410		return 0;
 411
 412	/*
 413	 * For live tree block (new tree blocks in current transaction),
 414	 * we need proper lock context to avoid race, which is impossible here.
 415	 * So we only checks tree blocks which is read from disk, whose
 416	 * generation <= fs_info->last_trans_committed.
 417	 */
 418	if (btrfs_header_generation(eb) > fs_info->last_trans_committed)
 419		return 0;
 420
 421	/* We have @first_key, so this @eb must have at least one item */
 422	if (btrfs_header_nritems(eb) == 0) {
 423		btrfs_err(fs_info,
 424		"invalid tree nritems, bytenr=%llu nritems=0 expect >0",
 425			  eb->start);
 426		WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
 427		return -EUCLEAN;
 428	}
 429
 430	if (found_level)
 431		btrfs_node_key_to_cpu(eb, &found_key, 0);
 432	else
 433		btrfs_item_key_to_cpu(eb, &found_key, 0);
 434	ret = btrfs_comp_cpu_keys(first_key, &found_key);
 435
 436	if (ret) {
 437		WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
 438		     KERN_ERR "BTRFS: tree first key check failed\n");
 439		btrfs_err(fs_info,
 440"tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
 441			  eb->start, parent_transid, first_key->objectid,
 442			  first_key->type, first_key->offset,
 443			  found_key.objectid, found_key.type,
 444			  found_key.offset);
 445	}
 446	return ret;
 447}
 448
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 449/*
 450 * helper to read a given tree block, doing retries as required when
 451 * the checksums don't match and we have alternate mirrors to try.
 452 *
 453 * @parent_transid:	expected transid, skip check if 0
 454 * @level:		expected level, mandatory check
 455 * @first_key:		expected key of first slot, skip check if NULL
 456 */
 457static int btree_read_extent_buffer_pages(struct extent_buffer *eb,
 458					  u64 parent_transid, int level,
 459					  struct btrfs_key *first_key)
 460{
 461	struct btrfs_fs_info *fs_info = eb->fs_info;
 462	struct extent_io_tree *io_tree;
 463	int failed = 0;
 464	int ret;
 465	int num_copies = 0;
 466	int mirror_num = 0;
 467	int failed_mirror = 0;
 468
 469	io_tree = &BTRFS_I(fs_info->btree_inode)->io_tree;
 
 470	while (1) {
 471		clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 472		ret = read_extent_buffer_pages(eb, WAIT_COMPLETE, mirror_num);
 473		if (!ret) {
 474			if (verify_parent_transid(io_tree, eb,
 475						   parent_transid, 0))
 476				ret = -EIO;
 477			else if (btrfs_verify_level_key(eb, level,
 478						first_key, parent_transid))
 479				ret = -EUCLEAN;
 480			else
 481				break;
 482		}
 483
 484		num_copies = btrfs_num_copies(fs_info,
 485					      eb->start, eb->len);
 486		if (num_copies == 1)
 487			break;
 488
 489		if (!failed_mirror) {
 490			failed = 1;
 491			failed_mirror = eb->read_mirror;
 492		}
 493
 494		mirror_num++;
 495		if (mirror_num == failed_mirror)
 496			mirror_num++;
 497
 498		if (mirror_num > num_copies)
 499			break;
 500	}
 501
 502	if (failed && !ret && failed_mirror)
 503		btrfs_repair_eb_io_failure(eb, failed_mirror);
 504
 505	return ret;
 506}
 507
 508/*
 509 * checksum a dirty tree block before IO.  This has extra checks to make sure
 510 * we only fill in the checksum field in the first page of a multi-page block
 511 */
 512
 513static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct page *page)
 514{
 515	u64 start = page_offset(page);
 516	u64 found_start;
 517	u8 result[BTRFS_CSUM_SIZE];
 518	u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
 519	struct extent_buffer *eb;
 520	int ret;
 521
 522	eb = (struct extent_buffer *)page->private;
 523	if (page != eb->pages[0])
 524		return 0;
 525
 526	found_start = btrfs_header_bytenr(eb);
 527	/*
 528	 * Please do not consolidate these warnings into a single if.
 529	 * It is useful to know what went wrong.
 530	 */
 531	if (WARN_ON(found_start != start))
 532		return -EUCLEAN;
 533	if (WARN_ON(!PageUptodate(page)))
 534		return -EUCLEAN;
 535
 536	ASSERT(memcmp_extent_buffer(eb, fs_info->fs_devices->metadata_uuid,
 537			btrfs_header_fsid(), BTRFS_FSID_SIZE) == 0);
 538
 539	if (csum_tree_block(eb, result))
 540		return -EINVAL;
 541
 542	if (btrfs_header_level(eb))
 543		ret = btrfs_check_node(eb);
 544	else
 545		ret = btrfs_check_leaf_full(eb);
 546
 547	if (ret < 0) {
 
 
 
 
 
 
 
 
 548		btrfs_err(fs_info,
 549		"block=%llu write time tree block corruption detected",
 550			  eb->start);
 551		return ret;
 
 552	}
 553	write_extent_buffer(eb, result, 0, csum_size);
 554
 555	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 556}
 557
 558static int check_tree_block_fsid(struct extent_buffer *eb)
 
 
 559{
 560	struct btrfs_fs_info *fs_info = eb->fs_info;
 561	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
 562	u8 fsid[BTRFS_FSID_SIZE];
 563	int ret = 1;
 564
 565	read_extent_buffer(eb, fsid, btrfs_header_fsid(), BTRFS_FSID_SIZE);
 566	while (fs_devices) {
 567		u8 *metadata_uuid;
 
 
 
 
 
 568
 569		/*
 570		 * Checking the incompat flag is only valid for the current
 571		 * fs. For seed devices it's forbidden to have their uuid
 572		 * changed so reading ->fsid in this case is fine
 573		 */
 574		if (fs_devices == fs_info->fs_devices &&
 575		    btrfs_fs_incompat(fs_info, METADATA_UUID))
 576			metadata_uuid = fs_devices->metadata_uuid;
 577		else
 578			metadata_uuid = fs_devices->fsid;
 579
 580		if (!memcmp(fsid, metadata_uuid, BTRFS_FSID_SIZE)) {
 581			ret = 0;
 582			break;
 
 
 
 
 583		}
 584		fs_devices = fs_devices->seed;
 
 
 
 
 585	}
 586	return ret;
 587}
 588
 589static int btree_readpage_end_io_hook(struct btrfs_io_bio *io_bio,
 590				      u64 phy_offset, struct page *page,
 591				      u64 start, u64 end, int mirror)
 
 
 
 592{
 
 
 593	u64 found_start;
 594	int found_level;
 595	struct extent_buffer *eb;
 596	struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 597	struct btrfs_fs_info *fs_info = root->fs_info;
 598	u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
 599	int ret = 0;
 600	u8 result[BTRFS_CSUM_SIZE];
 601	int reads_done;
 602
 603	if (!page->private)
 604		goto out;
 605
 606	eb = (struct extent_buffer *)page->private;
 
 
 607
 608	/* the pending IO might have been the only thing that kept this buffer
 609	 * in memory.  Make sure we have a ref for all this other checks
 
 
 
 
 
 
 
 
 610	 */
 611	extent_buffer_get(eb);
 
 
 
 612
 613	reads_done = atomic_dec_and_test(&eb->io_pages);
 614	if (!reads_done)
 615		goto err;
 616
 617	eb->read_mirror = mirror;
 618	if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
 619		ret = -EIO;
 620		goto err;
 621	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 622
 623	found_start = btrfs_header_bytenr(eb);
 624	if (found_start != eb->start) {
 625		btrfs_err_rl(fs_info, "bad tree block start, want %llu have %llu",
 626			     eb->start, found_start);
 
 627		ret = -EIO;
 628		goto err;
 629	}
 630	if (check_tree_block_fsid(eb)) {
 631		btrfs_err_rl(fs_info, "bad fsid on block %llu",
 632			     eb->start);
 633		ret = -EIO;
 634		goto err;
 635	}
 636	found_level = btrfs_header_level(eb);
 637	if (found_level >= BTRFS_MAX_LEVEL) {
 638		btrfs_err(fs_info, "bad tree block level %d on %llu",
 639			  (int)btrfs_header_level(eb), eb->start);
 
 640		ret = -EIO;
 641		goto err;
 642	}
 643
 644	btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb),
 645				       eb, found_level);
 646
 647	ret = csum_tree_block(eb, result);
 648	if (ret)
 649		goto err;
 650
 651	if (memcmp_extent_buffer(eb, result, 0, csum_size)) {
 652		u32 val;
 653		u32 found = 0;
 654
 655		memcpy(&found, result, csum_size);
 656
 657		read_extent_buffer(eb, &val, 0, csum_size);
 658		btrfs_warn_rl(fs_info,
 659		"%s checksum verify failed on %llu wanted %x found %x level %d",
 660			      fs_info->sb->s_id, eb->start,
 661			      val, found, btrfs_header_level(eb));
 
 
 662		ret = -EUCLEAN;
 663		goto err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 664	}
 665
 666	/*
 667	 * If this is a leaf block and it is corrupt, set the corrupt bit so
 668	 * that we don't try and read the other copies of this block, just
 669	 * return -EIO.
 670	 */
 671	if (found_level == 0 && btrfs_check_leaf_full(eb)) {
 672		set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 673		ret = -EIO;
 674	}
 675
 676	if (found_level > 0 && btrfs_check_node(eb))
 677		ret = -EIO;
 678
 679	if (!ret)
 680		set_extent_buffer_uptodate(eb);
 681	else
 682		btrfs_err(fs_info,
 683			  "block=%llu read time tree block corruption detected",
 684			  eb->start);
 685err:
 686	if (reads_done &&
 687	    test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
 688		btree_readahead_hook(eb, ret);
 689
 690	if (ret) {
 691		/*
 692		 * our io error hook is going to dec the io pages
 693		 * again, we have to make sure it has something
 694		 * to decrement
 695		 */
 696		atomic_inc(&eb->io_pages);
 697		clear_extent_buffer_uptodate(eb);
 698	}
 699	free_extent_buffer(eb);
 700out:
 701	return ret;
 702}
 703
 704static void end_workqueue_bio(struct bio *bio)
 
 705{
 706	struct btrfs_end_io_wq *end_io_wq = bio->bi_private;
 707	struct btrfs_fs_info *fs_info;
 708	struct btrfs_workqueue *wq;
 709	btrfs_work_func_t func;
 710
 711	fs_info = end_io_wq->info;
 712	end_io_wq->status = bio->bi_status;
 713
 714	if (bio_op(bio) == REQ_OP_WRITE) {
 715		if (end_io_wq->metadata == BTRFS_WQ_ENDIO_METADATA) {
 716			wq = fs_info->endio_meta_write_workers;
 717			func = btrfs_endio_meta_write_helper;
 718		} else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_FREE_SPACE) {
 719			wq = fs_info->endio_freespace_worker;
 720			func = btrfs_freespace_write_helper;
 721		} else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56) {
 722			wq = fs_info->endio_raid56_workers;
 723			func = btrfs_endio_raid56_helper;
 724		} else {
 725			wq = fs_info->endio_write_workers;
 726			func = btrfs_endio_write_helper;
 727		}
 728	} else {
 729		if (unlikely(end_io_wq->metadata ==
 730			     BTRFS_WQ_ENDIO_DIO_REPAIR)) {
 731			wq = fs_info->endio_repair_workers;
 732			func = btrfs_endio_repair_helper;
 733		} else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56) {
 734			wq = fs_info->endio_raid56_workers;
 735			func = btrfs_endio_raid56_helper;
 736		} else if (end_io_wq->metadata) {
 737			wq = fs_info->endio_meta_workers;
 738			func = btrfs_endio_meta_helper;
 739		} else {
 740			wq = fs_info->endio_workers;
 741			func = btrfs_endio_helper;
 742		}
 743	}
 
 
 
 
 
 744
 745	btrfs_init_work(&end_io_wq->work, func, end_workqueue_fn, NULL, NULL);
 746	btrfs_queue_work(wq, &end_io_wq->work);
 
 
 
 
 
 
 
 
 
 747}
 748
 749blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
 750			enum btrfs_wq_endio_type metadata)
 
 751{
 752	struct btrfs_end_io_wq *end_io_wq;
 
 
 753
 754	end_io_wq = kmem_cache_alloc(btrfs_end_io_wq_cache, GFP_NOFS);
 755	if (!end_io_wq)
 756		return BLK_STS_RESOURCE;
 757
 758	end_io_wq->private = bio->bi_private;
 759	end_io_wq->end_io = bio->bi_end_io;
 760	end_io_wq->info = info;
 761	end_io_wq->status = 0;
 762	end_io_wq->bio = bio;
 763	end_io_wq->metadata = metadata;
 764
 765	bio->bi_private = end_io_wq;
 766	bio->bi_end_io = end_workqueue_bio;
 767	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 768}
 769
 770static void run_one_async_start(struct btrfs_work *work)
 771{
 772	struct async_submit_bio *async;
 773	blk_status_t ret;
 774
 775	async = container_of(work, struct  async_submit_bio, work);
 776	ret = async->submit_bio_start(async->private_data, async->bio,
 777				      async->bio_offset);
 
 
 
 
 
 
 
 
 
 
 778	if (ret)
 779		async->status = ret;
 780}
 781
 782/*
 783 * In order to insert checksums into the metadata in large chunks, we wait
 784 * until bio submission time.   All the pages in the bio are checksummed and
 785 * sums are attached onto the ordered extent record.
 786 *
 787 * At IO completion time the csums attached on the ordered extent record are
 788 * inserted into the tree.
 789 */
 790static void run_one_async_done(struct btrfs_work *work)
 791{
 792	struct async_submit_bio *async;
 793	struct inode *inode;
 794	blk_status_t ret;
 795
 796	async = container_of(work, struct  async_submit_bio, work);
 797	inode = async->private_data;
 798
 799	/* If an error occurred we just want to clean up the bio and move on */
 800	if (async->status) {
 801		async->bio->bi_status = async->status;
 802		bio_endio(async->bio);
 803		return;
 804	}
 805
 806	ret = btrfs_map_bio(btrfs_sb(inode->i_sb), async->bio,
 807			async->mirror_num, 1);
 808	if (ret) {
 809		async->bio->bi_status = ret;
 810		bio_endio(async->bio);
 811	}
 
 812}
 813
 814static void run_one_async_free(struct btrfs_work *work)
 815{
 816	struct async_submit_bio *async;
 817
 818	async = container_of(work, struct  async_submit_bio, work);
 819	kfree(async);
 820}
 821
 822blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
 823				 int mirror_num, unsigned long bio_flags,
 824				 u64 bio_offset, void *private_data,
 825				 extent_submit_bio_start_t *submit_bio_start)
 
 
 
 
 
 826{
 
 827	struct async_submit_bio *async;
 828
 829	async = kmalloc(sizeof(*async), GFP_NOFS);
 830	if (!async)
 831		return BLK_STS_RESOURCE;
 832
 833	async->private_data = private_data;
 834	async->bio = bio;
 835	async->mirror_num = mirror_num;
 836	async->submit_bio_start = submit_bio_start;
 837
 838	btrfs_init_work(&async->work, btrfs_worker_helper, run_one_async_start,
 839			run_one_async_done, run_one_async_free);
 840
 841	async->bio_offset = bio_offset;
 842
 843	async->status = 0;
 844
 845	if (op_is_sync(bio->bi_opf))
 846		btrfs_set_work_high_priority(&async->work);
 847
 848	btrfs_queue_work(fs_info->workers, &async->work);
 849	return 0;
 850}
 851
 852static blk_status_t btree_csum_one_bio(struct bio *bio)
 853{
 854	struct bio_vec *bvec;
 855	struct btrfs_root *root;
 856	int ret = 0;
 857	struct bvec_iter_all iter_all;
 858
 859	ASSERT(!bio_flagged(bio, BIO_CLONED));
 860	bio_for_each_segment_all(bvec, bio, iter_all) {
 861		root = BTRFS_I(bvec->bv_page->mapping->host)->root;
 862		ret = csum_dirty_buffer(root->fs_info, bvec->bv_page);
 863		if (ret)
 864			break;
 865	}
 866
 867	return errno_to_blk_status(ret);
 868}
 869
 870static blk_status_t btree_submit_bio_start(void *private_data, struct bio *bio,
 871					     u64 bio_offset)
 872{
 873	/*
 874	 * when we're called for a write, we're already in the async
 875	 * submission context.  Just jump into btrfs_map_bio
 876	 */
 877	return btree_csum_one_bio(bio);
 878}
 879
 880static int check_async_write(struct btrfs_fs_info *fs_info,
 881			     struct btrfs_inode *bi)
 882{
 
 
 883	if (atomic_read(&bi->sync_writers))
 884		return 0;
 885	if (test_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags))
 886		return 0;
 887	return 1;
 888}
 889
 890static blk_status_t btree_submit_bio_hook(struct inode *inode, struct bio *bio,
 891					  int mirror_num,
 892					  unsigned long bio_flags)
 893{
 894	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 895	int async = check_async_write(fs_info, BTRFS_I(inode));
 896	blk_status_t ret;
 897
 898	if (bio_op(bio) != REQ_OP_WRITE) {
 899		/*
 900		 * called for a read, do the setup so that checksum validation
 901		 * can happen in the async kernel threads
 902		 */
 903		ret = btrfs_bio_wq_end_io(fs_info, bio,
 904					  BTRFS_WQ_ENDIO_METADATA);
 905		if (ret)
 906			goto out_w_error;
 907		ret = btrfs_map_bio(fs_info, bio, mirror_num, 0);
 908	} else if (!async) {
 909		ret = btree_csum_one_bio(bio);
 910		if (ret)
 911			goto out_w_error;
 912		ret = btrfs_map_bio(fs_info, bio, mirror_num, 0);
 913	} else {
 914		/*
 915		 * kthread helpers are used to submit writes so that
 916		 * checksumming can happen in parallel across all CPUs
 917		 */
 918		ret = btrfs_wq_submit_bio(fs_info, bio, mirror_num, 0,
 919					  0, inode, btree_submit_bio_start);
 920	}
 921
 922	if (ret)
 923		goto out_w_error;
 924	return 0;
 
 
 
 
 925
 926out_w_error:
 927	bio->bi_status = ret;
 928	bio_endio(bio);
 929	return ret;
 
 
 
 930}
 931
 932#ifdef CONFIG_MIGRATION
 933static int btree_migratepage(struct address_space *mapping,
 934			struct page *newpage, struct page *page,
 935			enum migrate_mode mode)
 936{
 937	/*
 938	 * we can't safely write a btree page from here,
 939	 * we haven't done the locking hook
 940	 */
 941	if (PageDirty(page))
 942		return -EAGAIN;
 943	/*
 944	 * Buffers may be managed in a filesystem specific way.
 945	 * We must have no buffers or drop them.
 946	 */
 947	if (page_has_private(page) &&
 948	    !try_to_release_page(page, GFP_KERNEL))
 949		return -EAGAIN;
 950	return migrate_page(mapping, newpage, page, mode);
 951}
 
 
 952#endif
 953
 954
 955static int btree_writepages(struct address_space *mapping,
 956			    struct writeback_control *wbc)
 957{
 958	struct btrfs_fs_info *fs_info;
 959	int ret;
 960
 961	if (wbc->sync_mode == WB_SYNC_NONE) {
 962
 963		if (wbc->for_kupdate)
 964			return 0;
 965
 966		fs_info = BTRFS_I(mapping->host)->root->fs_info;
 967		/* this is a bit racy, but that's ok */
 968		ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
 969					     BTRFS_DIRTY_METADATA_THRESH,
 970					     fs_info->dirty_metadata_batch);
 971		if (ret < 0)
 972			return 0;
 973	}
 974	return btree_write_cache_pages(mapping, wbc);
 975}
 976
 977static int btree_readpage(struct file *file, struct page *page)
 978{
 979	struct extent_io_tree *tree;
 980	tree = &BTRFS_I(page->mapping->host)->io_tree;
 981	return extent_read_full_page(tree, page, btree_get_extent, 0);
 982}
 983
 984static int btree_releasepage(struct page *page, gfp_t gfp_flags)
 985{
 986	if (PageWriteback(page) || PageDirty(page))
 987		return 0;
 988
 989	return try_release_extent_buffer(page);
 990}
 991
 992static void btree_invalidatepage(struct page *page, unsigned int offset,
 993				 unsigned int length)
 994{
 995	struct extent_io_tree *tree;
 996	tree = &BTRFS_I(page->mapping->host)->io_tree;
 997	extent_invalidatepage(tree, page, offset);
 998	btree_releasepage(page, GFP_NOFS);
 999	if (PagePrivate(page)) {
1000		btrfs_warn(BTRFS_I(page->mapping->host)->root->fs_info,
1001			   "page private not zero on page %llu",
1002			   (unsigned long long)page_offset(page));
1003		ClearPagePrivate(page);
1004		set_page_private(page, 0);
1005		put_page(page);
1006	}
1007}
1008
1009static int btree_set_page_dirty(struct page *page)
1010{
1011#ifdef DEBUG
 
 
 
 
 
1012	struct extent_buffer *eb;
 
 
1013
1014	BUG_ON(!PagePrivate(page));
1015	eb = (struct extent_buffer *)page->private;
1016	BUG_ON(!eb);
1017	BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
1018	BUG_ON(!atomic_read(&eb->refs));
1019	btrfs_assert_tree_locked(eb);
1020#endif
1021	return __set_page_dirty_nobuffers(page);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1022}
 
 
 
1023
1024static const struct address_space_operations btree_aops = {
1025	.readpage	= btree_readpage,
1026	.writepages	= btree_writepages,
1027	.releasepage	= btree_releasepage,
1028	.invalidatepage = btree_invalidatepage,
1029#ifdef CONFIG_MIGRATION
1030	.migratepage	= btree_migratepage,
1031#endif
1032	.set_page_dirty = btree_set_page_dirty,
1033};
1034
1035void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr)
1036{
1037	struct extent_buffer *buf = NULL;
1038	int ret;
1039
1040	buf = btrfs_find_create_tree_block(fs_info, bytenr);
1041	if (IS_ERR(buf))
1042		return;
1043
1044	ret = read_extent_buffer_pages(buf, WAIT_NONE, 0);
1045	if (ret < 0)
1046		free_extent_buffer_stale(buf);
1047	else
1048		free_extent_buffer(buf);
1049}
1050
1051struct extent_buffer *btrfs_find_create_tree_block(
1052						struct btrfs_fs_info *fs_info,
1053						u64 bytenr)
 
1054{
1055	if (btrfs_is_testing(fs_info))
1056		return alloc_test_extent_buffer(fs_info, bytenr);
1057	return alloc_extent_buffer(fs_info, bytenr);
1058}
1059
1060/*
1061 * Read tree block at logical address @bytenr and do variant basic but critical
1062 * verification.
1063 *
1064 * @parent_transid:	expected transid of this tree block, skip check if 0
1065 * @level:		expected level, mandatory check
1066 * @first_key:		expected key in slot 0, skip check if NULL
1067 */
1068struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
1069				      u64 parent_transid, int level,
1070				      struct btrfs_key *first_key)
1071{
1072	struct extent_buffer *buf = NULL;
1073	int ret;
1074
1075	buf = btrfs_find_create_tree_block(fs_info, bytenr);
 
 
 
1076	if (IS_ERR(buf))
1077		return buf;
1078
1079	ret = btree_read_extent_buffer_pages(buf, parent_transid,
1080					     level, first_key);
1081	if (ret) {
1082		free_extent_buffer_stale(buf);
1083		return ERR_PTR(ret);
1084	}
 
 
 
 
1085	return buf;
1086
1087}
1088
1089void btrfs_clean_tree_block(struct extent_buffer *buf)
1090{
1091	struct btrfs_fs_info *fs_info = buf->fs_info;
1092	if (btrfs_header_generation(buf) ==
1093	    fs_info->running_transaction->transid) {
1094		btrfs_assert_tree_locked(buf);
1095
1096		if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
1097			percpu_counter_add_batch(&fs_info->dirty_metadata_bytes,
1098						 -buf->len,
1099						 fs_info->dirty_metadata_batch);
1100			/* ugh, clear_extent_buffer_dirty needs to lock the page */
1101			btrfs_set_lock_blocking_write(buf);
1102			clear_extent_buffer_dirty(buf);
1103		}
1104	}
1105}
1106
1107static struct btrfs_subvolume_writers *btrfs_alloc_subvolume_writers(void)
1108{
1109	struct btrfs_subvolume_writers *writers;
1110	int ret;
1111
1112	writers = kmalloc(sizeof(*writers), GFP_NOFS);
1113	if (!writers)
1114		return ERR_PTR(-ENOMEM);
1115
1116	ret = percpu_counter_init(&writers->counter, 0, GFP_NOFS);
1117	if (ret < 0) {
1118		kfree(writers);
1119		return ERR_PTR(ret);
1120	}
1121
1122	init_waitqueue_head(&writers->wait);
1123	return writers;
1124}
1125
1126static void
1127btrfs_free_subvolume_writers(struct btrfs_subvolume_writers *writers)
1128{
1129	percpu_counter_destroy(&writers->counter);
1130	kfree(writers);
1131}
1132
1133static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
1134			 u64 objectid)
1135{
1136	bool dummy = test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state);
 
 
 
 
 
 
1137	root->node = NULL;
1138	root->commit_root = NULL;
1139	root->state = 0;
1140	root->orphan_cleanup_state = 0;
1141
1142	root->last_trans = 0;
1143	root->highest_objectid = 0;
1144	root->nr_delalloc_inodes = 0;
1145	root->nr_ordered_extents = 0;
1146	root->inode_tree = RB_ROOT;
1147	INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
1148	root->block_rsv = NULL;
 
1149
1150	INIT_LIST_HEAD(&root->dirty_list);
1151	INIT_LIST_HEAD(&root->root_list);
1152	INIT_LIST_HEAD(&root->delalloc_inodes);
1153	INIT_LIST_HEAD(&root->delalloc_root);
1154	INIT_LIST_HEAD(&root->ordered_extents);
1155	INIT_LIST_HEAD(&root->ordered_root);
1156	INIT_LIST_HEAD(&root->reloc_dirty_list);
1157	INIT_LIST_HEAD(&root->logged_list[0]);
1158	INIT_LIST_HEAD(&root->logged_list[1]);
1159	spin_lock_init(&root->inode_lock);
1160	spin_lock_init(&root->delalloc_lock);
1161	spin_lock_init(&root->ordered_extent_lock);
1162	spin_lock_init(&root->accounting_lock);
1163	spin_lock_init(&root->log_extents_lock[0]);
1164	spin_lock_init(&root->log_extents_lock[1]);
1165	spin_lock_init(&root->qgroup_meta_rsv_lock);
1166	mutex_init(&root->objectid_mutex);
1167	mutex_init(&root->log_mutex);
1168	mutex_init(&root->ordered_extent_mutex);
1169	mutex_init(&root->delalloc_mutex);
 
1170	init_waitqueue_head(&root->log_writer_wait);
1171	init_waitqueue_head(&root->log_commit_wait[0]);
1172	init_waitqueue_head(&root->log_commit_wait[1]);
1173	INIT_LIST_HEAD(&root->log_ctxs[0]);
1174	INIT_LIST_HEAD(&root->log_ctxs[1]);
1175	atomic_set(&root->log_commit[0], 0);
1176	atomic_set(&root->log_commit[1], 0);
1177	atomic_set(&root->log_writers, 0);
1178	atomic_set(&root->log_batch, 0);
1179	refcount_set(&root->refs, 1);
1180	atomic_set(&root->will_be_snapshotted, 0);
1181	atomic_set(&root->snapshot_force_cow, 0);
1182	atomic_set(&root->nr_swapfiles, 0);
1183	root->log_transid = 0;
1184	root->log_transid_committed = -1;
1185	root->last_log_commit = 0;
1186	if (!dummy)
1187		extent_io_tree_init(fs_info, &root->dirty_log_pages,
1188				    IO_TREE_ROOT_DIRTY_LOG_PAGES, NULL);
1189
1190	memset(&root->root_key, 0, sizeof(root->root_key));
1191	memset(&root->root_item, 0, sizeof(root->root_item));
1192	memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
1193	if (!dummy)
1194		root->defrag_trans_start = fs_info->generation;
1195	else
1196		root->defrag_trans_start = 0;
1197	root->root_key.objectid = objectid;
1198	root->anon_dev = 0;
 
 
 
 
 
 
1199
1200	spin_lock_init(&root->root_item_lock);
1201	btrfs_qgroup_init_swapped_blocks(&root->swapped_blocks);
 
 
 
 
 
 
1202}
1203
1204static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info,
1205		gfp_t flags)
1206{
1207	struct btrfs_root *root = kzalloc(sizeof(*root), flags);
1208	if (root)
1209		root->fs_info = fs_info;
1210	return root;
1211}
1212
1213#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
1214/* Should only be used by the testing infrastructure */
1215struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info)
1216{
1217	struct btrfs_root *root;
1218
1219	if (!fs_info)
1220		return ERR_PTR(-EINVAL);
1221
1222	root = btrfs_alloc_root(fs_info, GFP_KERNEL);
1223	if (!root)
1224		return ERR_PTR(-ENOMEM);
1225
1226	/* We don't use the stripesize in selftest, set it as sectorsize */
1227	__setup_root(root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
1228	root->alloc_bytenr = 0;
1229
1230	return root;
1231}
1232#endif
1233
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1234struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
1235				     u64 objectid)
1236{
1237	struct btrfs_fs_info *fs_info = trans->fs_info;
1238	struct extent_buffer *leaf;
1239	struct btrfs_root *tree_root = fs_info->tree_root;
1240	struct btrfs_root *root;
1241	struct btrfs_key key;
1242	unsigned int nofs_flag;
1243	int ret = 0;
1244	uuid_le uuid = NULL_UUID_LE;
1245
1246	/*
1247	 * We're holding a transaction handle, so use a NOFS memory allocation
1248	 * context to avoid deadlock if reclaim happens.
1249	 */
1250	nofs_flag = memalloc_nofs_save();
1251	root = btrfs_alloc_root(fs_info, GFP_KERNEL);
1252	memalloc_nofs_restore(nofs_flag);
1253	if (!root)
1254		return ERR_PTR(-ENOMEM);
1255
1256	__setup_root(root, fs_info, objectid);
1257	root->root_key.objectid = objectid;
1258	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1259	root->root_key.offset = 0;
1260
1261	leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
 
1262	if (IS_ERR(leaf)) {
1263		ret = PTR_ERR(leaf);
1264		leaf = NULL;
1265		goto fail;
1266	}
1267
1268	root->node = leaf;
1269	btrfs_mark_buffer_dirty(leaf);
1270
1271	root->commit_root = btrfs_root_node(root);
1272	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
1273
1274	root->root_item.flags = 0;
1275	root->root_item.byte_limit = 0;
1276	btrfs_set_root_bytenr(&root->root_item, leaf->start);
1277	btrfs_set_root_generation(&root->root_item, trans->transid);
1278	btrfs_set_root_level(&root->root_item, 0);
1279	btrfs_set_root_refs(&root->root_item, 1);
1280	btrfs_set_root_used(&root->root_item, leaf->len);
1281	btrfs_set_root_last_snapshot(&root->root_item, 0);
1282	btrfs_set_root_dirid(&root->root_item, 0);
1283	if (is_fstree(objectid))
1284		uuid_le_gen(&uuid);
1285	memcpy(root->root_item.uuid, uuid.b, BTRFS_UUID_SIZE);
1286	root->root_item.drop_level = 0;
 
 
 
1287
1288	key.objectid = objectid;
1289	key.type = BTRFS_ROOT_ITEM_KEY;
1290	key.offset = 0;
1291	ret = btrfs_insert_root(trans, tree_root, &key, &root->root_item);
1292	if (ret)
1293		goto fail;
1294
1295	btrfs_tree_unlock(leaf);
1296
1297	return root;
1298
1299fail:
1300	if (leaf) {
1301		btrfs_tree_unlock(leaf);
1302		free_extent_buffer(root->commit_root);
1303		free_extent_buffer(leaf);
1304	}
1305	kfree(root);
1306
1307	return ERR_PTR(ret);
1308}
1309
1310static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
1311					 struct btrfs_fs_info *fs_info)
1312{
1313	struct btrfs_root *root;
1314	struct extent_buffer *leaf;
1315
1316	root = btrfs_alloc_root(fs_info, GFP_NOFS);
1317	if (!root)
1318		return ERR_PTR(-ENOMEM);
1319
1320	__setup_root(root, fs_info, BTRFS_TREE_LOG_OBJECTID);
1321
1322	root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1323	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1324	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
1325
 
 
 
 
 
 
 
 
1326	/*
1327	 * DON'T set REF_COWS for log trees
 
 
 
1328	 *
1329	 * log trees do not get reference counted because they go away
1330	 * before a real commit is actually done.  They do store pointers
1331	 * to file data extents, and those reference counts still get
1332	 * updated (along with back refs to the log tree).
1333	 */
1334
1335	leaf = btrfs_alloc_tree_block(trans, root, 0, BTRFS_TREE_LOG_OBJECTID,
1336			NULL, 0, 0, 0);
1337	if (IS_ERR(leaf)) {
1338		kfree(root);
1339		return ERR_CAST(leaf);
1340	}
1341
1342	root->node = leaf;
1343
1344	btrfs_mark_buffer_dirty(root->node);
1345	btrfs_tree_unlock(root->node);
1346	return root;
 
1347}
1348
1349int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1350			     struct btrfs_fs_info *fs_info)
1351{
1352	struct btrfs_root *log_root;
1353
1354	log_root = alloc_log_tree(trans, fs_info);
1355	if (IS_ERR(log_root))
1356		return PTR_ERR(log_root);
 
 
 
 
 
 
 
 
 
 
1357	WARN_ON(fs_info->log_root_tree);
1358	fs_info->log_root_tree = log_root;
1359	return 0;
1360}
1361
1362int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1363		       struct btrfs_root *root)
1364{
1365	struct btrfs_fs_info *fs_info = root->fs_info;
1366	struct btrfs_root *log_root;
1367	struct btrfs_inode_item *inode_item;
 
1368
1369	log_root = alloc_log_tree(trans, fs_info);
1370	if (IS_ERR(log_root))
1371		return PTR_ERR(log_root);
1372
 
 
 
 
 
 
1373	log_root->last_trans = trans->transid;
1374	log_root->root_key.offset = root->root_key.objectid;
1375
1376	inode_item = &log_root->root_item.inode;
1377	btrfs_set_stack_inode_generation(inode_item, 1);
1378	btrfs_set_stack_inode_size(inode_item, 3);
1379	btrfs_set_stack_inode_nlink(inode_item, 1);
1380	btrfs_set_stack_inode_nbytes(inode_item,
1381				     fs_info->nodesize);
1382	btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
1383
1384	btrfs_set_root_node(&log_root->root_item, log_root->node);
1385
1386	WARN_ON(root->log_root);
1387	root->log_root = log_root;
1388	root->log_transid = 0;
1389	root->log_transid_committed = -1;
1390	root->last_log_commit = 0;
1391	return 0;
1392}
1393
1394static struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
1395					       struct btrfs_key *key)
 
1396{
1397	struct btrfs_root *root;
 
1398	struct btrfs_fs_info *fs_info = tree_root->fs_info;
1399	struct btrfs_path *path;
1400	u64 generation;
1401	int ret;
1402	int level;
1403
1404	path = btrfs_alloc_path();
1405	if (!path)
1406		return ERR_PTR(-ENOMEM);
1407
1408	root = btrfs_alloc_root(fs_info, GFP_NOFS);
1409	if (!root) {
1410		ret = -ENOMEM;
1411		goto alloc_fail;
1412	}
1413
1414	__setup_root(root, fs_info, key->objectid);
1415
1416	ret = btrfs_find_root(tree_root, key, path,
1417			      &root->root_item, &root->root_key);
1418	if (ret) {
1419		if (ret > 0)
1420			ret = -ENOENT;
1421		goto find_fail;
1422	}
1423
1424	generation = btrfs_root_generation(&root->root_item);
1425	level = btrfs_root_level(&root->root_item);
1426	root->node = read_tree_block(fs_info,
1427				     btrfs_root_bytenr(&root->root_item),
1428				     generation, level, NULL);
 
 
1429	if (IS_ERR(root->node)) {
1430		ret = PTR_ERR(root->node);
1431		goto find_fail;
1432	} else if (!btrfs_buffer_uptodate(root->node, generation, 0)) {
 
 
1433		ret = -EIO;
1434		free_extent_buffer(root->node);
1435		goto find_fail;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1436	}
1437	root->commit_root = btrfs_root_node(root);
1438out:
1439	btrfs_free_path(path);
1440	return root;
1441
1442find_fail:
1443	kfree(root);
1444alloc_fail:
1445	root = ERR_PTR(ret);
1446	goto out;
1447}
1448
1449struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root,
1450				      struct btrfs_key *location)
1451{
1452	struct btrfs_root *root;
 
1453
1454	root = btrfs_read_tree_root(tree_root, location);
1455	if (IS_ERR(root))
1456		return root;
1457
1458	if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
1459		set_bit(BTRFS_ROOT_REF_COWS, &root->state);
1460		btrfs_check_and_init_root_item(&root->root_item);
1461	}
1462
1463	return root;
1464}
1465
1466int btrfs_init_fs_root(struct btrfs_root *root)
 
 
 
 
 
1467{
1468	int ret;
1469	struct btrfs_subvolume_writers *writers;
1470
1471	root->free_ino_ctl = kzalloc(sizeof(*root->free_ino_ctl), GFP_NOFS);
1472	root->free_ino_pinned = kzalloc(sizeof(*root->free_ino_pinned),
1473					GFP_NOFS);
1474	if (!root->free_ino_pinned || !root->free_ino_ctl) {
1475		ret = -ENOMEM;
 
 
 
1476		goto fail;
1477	}
1478
1479	writers = btrfs_alloc_subvolume_writers();
1480	if (IS_ERR(writers)) {
1481		ret = PTR_ERR(writers);
1482		goto fail;
1483	}
1484	root->subv_writers = writers;
1485
1486	btrfs_init_free_ino_ctl(root);
1487	spin_lock_init(&root->ino_cache_lock);
1488	init_waitqueue_head(&root->ino_cache_wait);
1489
1490	ret = get_anon_bdev(&root->anon_dev);
1491	if (ret)
1492		goto fail;
 
 
 
 
 
 
 
 
 
 
 
1493
1494	mutex_lock(&root->objectid_mutex);
1495	ret = btrfs_find_highest_objectid(root,
1496					&root->highest_objectid);
1497	if (ret) {
1498		mutex_unlock(&root->objectid_mutex);
1499		goto fail;
1500	}
1501
1502	ASSERT(root->highest_objectid <= BTRFS_LAST_FREE_OBJECTID);
1503
1504	mutex_unlock(&root->objectid_mutex);
1505
1506	return 0;
1507fail:
1508	/* The caller is responsible to call btrfs_free_fs_root */
1509	return ret;
1510}
1511
1512struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
1513					u64 root_id)
1514{
1515	struct btrfs_root *root;
1516
1517	spin_lock(&fs_info->fs_roots_radix_lock);
1518	root = radix_tree_lookup(&fs_info->fs_roots_radix,
1519				 (unsigned long)root_id);
 
 
1520	spin_unlock(&fs_info->fs_roots_radix_lock);
1521	return root;
1522}
1523
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1524int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
1525			 struct btrfs_root *root)
1526{
1527	int ret;
1528
1529	ret = radix_tree_preload(GFP_NOFS);
1530	if (ret)
1531		return ret;
1532
1533	spin_lock(&fs_info->fs_roots_radix_lock);
1534	ret = radix_tree_insert(&fs_info->fs_roots_radix,
1535				(unsigned long)root->root_key.objectid,
1536				root);
1537	if (ret == 0)
 
1538		set_bit(BTRFS_ROOT_IN_RADIX, &root->state);
 
1539	spin_unlock(&fs_info->fs_roots_radix_lock);
1540	radix_tree_preload_end();
1541
1542	return ret;
1543}
1544
1545struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
1546				     struct btrfs_key *location,
1547				     bool check_ref)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1548{
1549	struct btrfs_root *root;
1550	struct btrfs_path *path;
1551	struct btrfs_key key;
1552	int ret;
1553
1554	if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1555		return fs_info->tree_root;
1556	if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
1557		return fs_info->extent_root;
1558	if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
1559		return fs_info->chunk_root;
1560	if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
1561		return fs_info->dev_root;
1562	if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
1563		return fs_info->csum_root;
1564	if (location->objectid == BTRFS_QUOTA_TREE_OBJECTID)
1565		return fs_info->quota_root ? fs_info->quota_root :
1566					     ERR_PTR(-ENOENT);
1567	if (location->objectid == BTRFS_UUID_TREE_OBJECTID)
1568		return fs_info->uuid_root ? fs_info->uuid_root :
1569					    ERR_PTR(-ENOENT);
1570	if (location->objectid == BTRFS_FREE_SPACE_TREE_OBJECTID)
1571		return fs_info->free_space_root ? fs_info->free_space_root :
1572						  ERR_PTR(-ENOENT);
1573again:
1574	root = btrfs_lookup_fs_root(fs_info, location->objectid);
1575	if (root) {
1576		if (check_ref && btrfs_root_refs(&root->root_item) == 0)
 
 
 
1577			return ERR_PTR(-ENOENT);
 
1578		return root;
1579	}
1580
1581	root = btrfs_read_fs_root(fs_info->tree_root, location);
 
 
 
1582	if (IS_ERR(root))
1583		return root;
1584
1585	if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1586		ret = -ENOENT;
1587		goto fail;
1588	}
1589
1590	ret = btrfs_init_fs_root(root);
1591	if (ret)
1592		goto fail;
1593
1594	path = btrfs_alloc_path();
1595	if (!path) {
1596		ret = -ENOMEM;
1597		goto fail;
1598	}
1599	key.objectid = BTRFS_ORPHAN_OBJECTID;
1600	key.type = BTRFS_ORPHAN_ITEM_KEY;
1601	key.offset = location->objectid;
1602
1603	ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
1604	btrfs_free_path(path);
1605	if (ret < 0)
1606		goto fail;
1607	if (ret == 0)
1608		set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state);
1609
1610	ret = btrfs_insert_fs_root(fs_info, root);
1611	if (ret) {
1612		if (ret == -EEXIST) {
1613			btrfs_free_fs_root(root);
1614			goto again;
1615		}
1616		goto fail;
1617	}
1618	return root;
1619fail:
1620	btrfs_free_fs_root(root);
 
 
 
 
 
 
 
 
1621	return ERR_PTR(ret);
1622}
1623
1624static int btrfs_congested_fn(void *congested_data, int bdi_bits)
 
 
 
 
 
 
 
 
1625{
1626	struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
1627	int ret = 0;
1628	struct btrfs_device *device;
1629	struct backing_dev_info *bdi;
1630
1631	rcu_read_lock();
1632	list_for_each_entry_rcu(device, &info->fs_devices->devices, dev_list) {
1633		if (!device->bdev)
1634			continue;
1635		bdi = device->bdev->bd_bdi;
1636		if (bdi_congested(bdi, bdi_bits)) {
1637			ret = 1;
1638			break;
1639		}
1640	}
1641	rcu_read_unlock();
1642	return ret;
1643}
1644
1645/*
1646 * called by the kthread helper functions to finally call the bio end_io
1647 * functions.  This is where read checksum verification actually happens
 
 
 
 
 
 
 
 
 
 
1648 */
1649static void end_workqueue_fn(struct btrfs_work *work)
 
 
1650{
1651	struct bio *bio;
1652	struct btrfs_end_io_wq *end_io_wq;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1653
1654	end_io_wq = container_of(work, struct btrfs_end_io_wq, work);
1655	bio = end_io_wq->bio;
 
 
 
1656
1657	bio->bi_status = end_io_wq->status;
1658	bio->bi_private = end_io_wq->private;
1659	bio->bi_end_io = end_io_wq->end_io;
1660	kmem_cache_free(btrfs_end_io_wq_cache, end_io_wq);
1661	bio_endio(bio);
1662}
1663
1664static int cleaner_kthread(void *arg)
1665{
1666	struct btrfs_root *root = arg;
1667	struct btrfs_fs_info *fs_info = root->fs_info;
1668	int again;
1669
1670	while (1) {
1671		again = 0;
1672
1673		set_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1674
1675		/* Make the cleaner go to sleep early. */
1676		if (btrfs_need_cleaner_sleep(fs_info))
1677			goto sleep;
1678
1679		/*
1680		 * Do not do anything if we might cause open_ctree() to block
1681		 * before we have finished mounting the filesystem.
1682		 */
1683		if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags))
1684			goto sleep;
1685
1686		if (!mutex_trylock(&fs_info->cleaner_mutex))
1687			goto sleep;
1688
1689		/*
1690		 * Avoid the problem that we change the status of the fs
1691		 * during the above check and trylock.
1692		 */
1693		if (btrfs_need_cleaner_sleep(fs_info)) {
1694			mutex_unlock(&fs_info->cleaner_mutex);
1695			goto sleep;
1696		}
1697
1698		btrfs_run_delayed_iputs(fs_info);
1699
1700		again = btrfs_clean_one_deleted_snapshot(root);
1701		mutex_unlock(&fs_info->cleaner_mutex);
1702
1703		/*
1704		 * The defragger has dealt with the R/O remount and umount,
1705		 * needn't do anything special here.
1706		 */
1707		btrfs_run_defrag_inodes(fs_info);
1708
1709		/*
1710		 * Acquires fs_info->delete_unused_bgs_mutex to avoid racing
1711		 * with relocation (btrfs_relocate_chunk) and relocation
1712		 * acquires fs_info->cleaner_mutex (btrfs_relocate_block_group)
1713		 * after acquiring fs_info->delete_unused_bgs_mutex. So we
1714		 * can't hold, nor need to, fs_info->cleaner_mutex when deleting
1715		 * unused block groups.
1716		 */
1717		btrfs_delete_unused_bgs(fs_info);
 
 
 
 
 
 
 
1718sleep:
1719		clear_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1720		if (kthread_should_park())
1721			kthread_parkme();
1722		if (kthread_should_stop())
1723			return 0;
1724		if (!again) {
1725			set_current_state(TASK_INTERRUPTIBLE);
1726			schedule();
1727			__set_current_state(TASK_RUNNING);
1728		}
1729	}
1730}
1731
1732static int transaction_kthread(void *arg)
1733{
1734	struct btrfs_root *root = arg;
1735	struct btrfs_fs_info *fs_info = root->fs_info;
1736	struct btrfs_trans_handle *trans;
1737	struct btrfs_transaction *cur;
1738	u64 transid;
1739	time64_t now;
1740	unsigned long delay;
1741	bool cannot_commit;
1742
1743	do {
1744		cannot_commit = false;
1745		delay = HZ * fs_info->commit_interval;
1746		mutex_lock(&fs_info->transaction_kthread_mutex);
1747
1748		spin_lock(&fs_info->trans_lock);
1749		cur = fs_info->running_transaction;
1750		if (!cur) {
1751			spin_unlock(&fs_info->trans_lock);
1752			goto sleep;
1753		}
1754
1755		now = ktime_get_seconds();
1756		if (cur->state < TRANS_STATE_BLOCKED &&
1757		    !test_bit(BTRFS_FS_NEED_ASYNC_COMMIT, &fs_info->flags) &&
1758		    (now < cur->start_time ||
1759		     now - cur->start_time < fs_info->commit_interval)) {
1760			spin_unlock(&fs_info->trans_lock);
1761			delay = HZ * 5;
 
 
1762			goto sleep;
1763		}
1764		transid = cur->transid;
1765		spin_unlock(&fs_info->trans_lock);
1766
1767		/* If the file system is aborted, this will always fail. */
1768		trans = btrfs_attach_transaction(root);
1769		if (IS_ERR(trans)) {
1770			if (PTR_ERR(trans) != -ENOENT)
1771				cannot_commit = true;
1772			goto sleep;
1773		}
1774		if (transid == trans->transid) {
1775			btrfs_commit_transaction(trans);
1776		} else {
1777			btrfs_end_transaction(trans);
1778		}
1779sleep:
1780		wake_up_process(fs_info->cleaner_kthread);
1781		mutex_unlock(&fs_info->transaction_kthread_mutex);
1782
1783		if (unlikely(test_bit(BTRFS_FS_STATE_ERROR,
1784				      &fs_info->fs_state)))
1785			btrfs_cleanup_transaction(fs_info);
1786		if (!kthread_should_stop() &&
1787				(!btrfs_transaction_blocked(fs_info) ||
1788				 cannot_commit))
1789			schedule_timeout_interruptible(delay);
1790	} while (!kthread_should_stop());
1791	return 0;
1792}
1793
1794/*
1795 * this will find the highest generation in the array of
1796 * root backups.  The index of the highest array is returned,
1797 * or -1 if we can't find anything.
1798 *
1799 * We check to make sure the array is valid by comparing the
1800 * generation of the latest  root in the array with the generation
1801 * in the super block.  If they don't match we pitch it.
1802 */
1803static int find_newest_super_backup(struct btrfs_fs_info *info, u64 newest_gen)
1804{
 
1805	u64 cur;
1806	int newest_index = -1;
1807	struct btrfs_root_backup *root_backup;
1808	int i;
1809
1810	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
1811		root_backup = info->super_copy->super_roots + i;
1812		cur = btrfs_backup_tree_root_gen(root_backup);
1813		if (cur == newest_gen)
1814			newest_index = i;
1815	}
1816
1817	/* check to see if we actually wrapped around */
1818	if (newest_index == BTRFS_NUM_BACKUP_ROOTS - 1) {
1819		root_backup = info->super_copy->super_roots;
1820		cur = btrfs_backup_tree_root_gen(root_backup);
1821		if (cur == newest_gen)
1822			newest_index = 0;
1823	}
1824	return newest_index;
1825}
1826
1827
1828/*
1829 * find the oldest backup so we know where to store new entries
1830 * in the backup array.  This will set the backup_root_index
1831 * field in the fs_info struct
1832 */
1833static void find_oldest_super_backup(struct btrfs_fs_info *info,
1834				     u64 newest_gen)
1835{
1836	int newest_index = -1;
1837
1838	newest_index = find_newest_super_backup(info, newest_gen);
1839	/* if there was garbage in there, just move along */
1840	if (newest_index == -1) {
1841		info->backup_root_index = 0;
1842	} else {
1843		info->backup_root_index = (newest_index + 1) % BTRFS_NUM_BACKUP_ROOTS;
1844	}
1845}
1846
1847/*
1848 * copy all the root pointers into the super backup array.
1849 * this will bump the backup pointer by one when it is
1850 * done
1851 */
1852static void backup_super_roots(struct btrfs_fs_info *info)
1853{
1854	int next_backup;
1855	struct btrfs_root_backup *root_backup;
1856	int last_backup;
1857
1858	next_backup = info->backup_root_index;
1859	last_backup = (next_backup + BTRFS_NUM_BACKUP_ROOTS - 1) %
1860		BTRFS_NUM_BACKUP_ROOTS;
1861
1862	/*
1863	 * just overwrite the last backup if we're at the same generation
1864	 * this happens only at umount
1865	 */
1866	root_backup = info->super_for_commit->super_roots + last_backup;
1867	if (btrfs_backup_tree_root_gen(root_backup) ==
1868	    btrfs_header_generation(info->tree_root->node))
1869		next_backup = last_backup;
1870
1871	root_backup = info->super_for_commit->super_roots + next_backup;
1872
1873	/*
1874	 * make sure all of our padding and empty slots get zero filled
1875	 * regardless of which ones we use today
1876	 */
1877	memset(root_backup, 0, sizeof(*root_backup));
1878
1879	info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
1880
1881	btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
1882	btrfs_set_backup_tree_root_gen(root_backup,
1883			       btrfs_header_generation(info->tree_root->node));
1884
1885	btrfs_set_backup_tree_root_level(root_backup,
1886			       btrfs_header_level(info->tree_root->node));
1887
1888	btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
1889	btrfs_set_backup_chunk_root_gen(root_backup,
1890			       btrfs_header_generation(info->chunk_root->node));
1891	btrfs_set_backup_chunk_root_level(root_backup,
1892			       btrfs_header_level(info->chunk_root->node));
1893
1894	btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start);
1895	btrfs_set_backup_extent_root_gen(root_backup,
1896			       btrfs_header_generation(info->extent_root->node));
1897	btrfs_set_backup_extent_root_level(root_backup,
1898			       btrfs_header_level(info->extent_root->node));
 
 
 
 
 
 
 
 
 
 
 
 
1899
1900	/*
1901	 * we might commit during log recovery, which happens before we set
1902	 * the fs_root.  Make sure it is valid before we fill it in.
1903	 */
1904	if (info->fs_root && info->fs_root->node) {
1905		btrfs_set_backup_fs_root(root_backup,
1906					 info->fs_root->node->start);
1907		btrfs_set_backup_fs_root_gen(root_backup,
1908			       btrfs_header_generation(info->fs_root->node));
1909		btrfs_set_backup_fs_root_level(root_backup,
1910			       btrfs_header_level(info->fs_root->node));
1911	}
1912
1913	btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
1914	btrfs_set_backup_dev_root_gen(root_backup,
1915			       btrfs_header_generation(info->dev_root->node));
1916	btrfs_set_backup_dev_root_level(root_backup,
1917				       btrfs_header_level(info->dev_root->node));
1918
1919	btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start);
1920	btrfs_set_backup_csum_root_gen(root_backup,
1921			       btrfs_header_generation(info->csum_root->node));
1922	btrfs_set_backup_csum_root_level(root_backup,
1923			       btrfs_header_level(info->csum_root->node));
1924
1925	btrfs_set_backup_total_bytes(root_backup,
1926			     btrfs_super_total_bytes(info->super_copy));
1927	btrfs_set_backup_bytes_used(root_backup,
1928			     btrfs_super_bytes_used(info->super_copy));
1929	btrfs_set_backup_num_devices(root_backup,
1930			     btrfs_super_num_devices(info->super_copy));
1931
1932	/*
1933	 * if we don't copy this out to the super_copy, it won't get remembered
1934	 * for the next commit
1935	 */
1936	memcpy(&info->super_copy->super_roots,
1937	       &info->super_for_commit->super_roots,
1938	       sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
1939}
1940
1941/*
1942 * this copies info out of the root backup array and back into
1943 * the in-memory super block.  It is meant to help iterate through
1944 * the array, so you send it the number of backups you've already
1945 * tried and the last backup index you used.
1946 *
1947 * this returns -1 when it has tried all the backups
 
 
 
1948 */
1949static noinline int next_root_backup(struct btrfs_fs_info *info,
1950				     struct btrfs_super_block *super,
1951				     int *num_backups_tried, int *backup_index)
1952{
 
 
1953	struct btrfs_root_backup *root_backup;
1954	int newest = *backup_index;
1955
1956	if (*num_backups_tried == 0) {
1957		u64 gen = btrfs_super_generation(super);
 
1958
1959		newest = find_newest_super_backup(info, gen);
1960		if (newest == -1)
1961			return -1;
1962
1963		*backup_index = newest;
1964		*num_backups_tried = 1;
1965	} else if (*num_backups_tried == BTRFS_NUM_BACKUP_ROOTS) {
1966		/* we've tried all the backups, all done */
1967		return -1;
1968	} else {
1969		/* jump to the next oldest backup */
1970		newest = (*backup_index + BTRFS_NUM_BACKUP_ROOTS - 1) %
1971			BTRFS_NUM_BACKUP_ROOTS;
1972		*backup_index = newest;
1973		*num_backups_tried += 1;
1974	}
1975	root_backup = super->super_roots + newest;
 
1976
1977	btrfs_set_super_generation(super,
1978				   btrfs_backup_tree_root_gen(root_backup));
1979	btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
1980	btrfs_set_super_root_level(super,
1981				   btrfs_backup_tree_root_level(root_backup));
1982	btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
1983
1984	/*
1985	 * fixme: the total bytes and num_devices need to match or we should
1986	 * need a fsck
1987	 */
1988	btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
1989	btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
1990	return 0;
 
1991}
1992
1993/* helper to cleanup workers */
1994static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
1995{
1996	btrfs_destroy_workqueue(fs_info->fixup_workers);
1997	btrfs_destroy_workqueue(fs_info->delalloc_workers);
 
1998	btrfs_destroy_workqueue(fs_info->workers);
1999	btrfs_destroy_workqueue(fs_info->endio_workers);
2000	btrfs_destroy_workqueue(fs_info->endio_raid56_workers);
2001	btrfs_destroy_workqueue(fs_info->endio_repair_workers);
2002	btrfs_destroy_workqueue(fs_info->rmw_workers);
 
 
2003	btrfs_destroy_workqueue(fs_info->endio_write_workers);
2004	btrfs_destroy_workqueue(fs_info->endio_freespace_worker);
2005	btrfs_destroy_workqueue(fs_info->submit_workers);
2006	btrfs_destroy_workqueue(fs_info->delayed_workers);
2007	btrfs_destroy_workqueue(fs_info->caching_workers);
2008	btrfs_destroy_workqueue(fs_info->readahead_workers);
2009	btrfs_destroy_workqueue(fs_info->flush_workers);
2010	btrfs_destroy_workqueue(fs_info->qgroup_rescan_workers);
 
 
2011	/*
2012	 * Now that all other work queues are destroyed, we can safely destroy
2013	 * the queues used for metadata I/O, since tasks from those other work
2014	 * queues can do metadata I/O operations.
2015	 */
2016	btrfs_destroy_workqueue(fs_info->endio_meta_workers);
2017	btrfs_destroy_workqueue(fs_info->endio_meta_write_workers);
2018}
2019
2020static void free_root_extent_buffers(struct btrfs_root *root)
2021{
2022	if (root) {
2023		free_extent_buffer(root->node);
2024		free_extent_buffer(root->commit_root);
2025		root->node = NULL;
2026		root->commit_root = NULL;
2027	}
2028}
2029
 
 
 
 
 
 
 
 
 
 
2030/* helper to cleanup tree roots */
2031static void free_root_pointers(struct btrfs_fs_info *info, int chunk_root)
2032{
2033	free_root_extent_buffers(info->tree_root);
2034
 
2035	free_root_extent_buffers(info->dev_root);
2036	free_root_extent_buffers(info->extent_root);
2037	free_root_extent_buffers(info->csum_root);
2038	free_root_extent_buffers(info->quota_root);
2039	free_root_extent_buffers(info->uuid_root);
2040	if (chunk_root)
 
 
 
2041		free_root_extent_buffers(info->chunk_root);
2042	free_root_extent_buffers(info->free_space_root);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2043}
2044
2045void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info)
2046{
2047	int ret;
2048	struct btrfs_root *gang[8];
2049	int i;
2050
2051	while (!list_empty(&fs_info->dead_roots)) {
2052		gang[0] = list_entry(fs_info->dead_roots.next,
2053				     struct btrfs_root, root_list);
2054		list_del(&gang[0]->root_list);
2055
2056		if (test_bit(BTRFS_ROOT_IN_RADIX, &gang[0]->state)) {
2057			btrfs_drop_and_free_fs_root(fs_info, gang[0]);
2058		} else {
2059			free_extent_buffer(gang[0]->node);
2060			free_extent_buffer(gang[0]->commit_root);
2061			btrfs_put_fs_root(gang[0]);
2062		}
2063	}
2064
2065	while (1) {
2066		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2067					     (void **)gang, 0,
2068					     ARRAY_SIZE(gang));
2069		if (!ret)
2070			break;
2071		for (i = 0; i < ret; i++)
2072			btrfs_drop_and_free_fs_root(fs_info, gang[i]);
2073	}
2074
2075	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
2076		btrfs_free_log_root_tree(NULL, fs_info);
2077		btrfs_destroy_pinned_extent(fs_info, fs_info->pinned_extents);
2078	}
2079}
2080
2081static void btrfs_init_scrub(struct btrfs_fs_info *fs_info)
2082{
2083	mutex_init(&fs_info->scrub_lock);
2084	atomic_set(&fs_info->scrubs_running, 0);
2085	atomic_set(&fs_info->scrub_pause_req, 0);
2086	atomic_set(&fs_info->scrubs_paused, 0);
2087	atomic_set(&fs_info->scrub_cancel_req, 0);
2088	init_waitqueue_head(&fs_info->scrub_pause_wait);
2089	refcount_set(&fs_info->scrub_workers_refcnt, 0);
2090}
2091
2092static void btrfs_init_balance(struct btrfs_fs_info *fs_info)
2093{
2094	spin_lock_init(&fs_info->balance_lock);
2095	mutex_init(&fs_info->balance_mutex);
2096	atomic_set(&fs_info->balance_pause_req, 0);
2097	atomic_set(&fs_info->balance_cancel_req, 0);
2098	fs_info->balance_ctl = NULL;
2099	init_waitqueue_head(&fs_info->balance_wait_q);
 
2100}
2101
2102static void btrfs_init_btree_inode(struct btrfs_fs_info *fs_info)
2103{
2104	struct inode *inode = fs_info->btree_inode;
 
 
2105
2106	inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
2107	set_nlink(inode, 1);
2108	/*
2109	 * we set the i_size on the btree inode to the max possible int.
2110	 * the real end of the address space is determined by all of
2111	 * the devices in the system
2112	 */
2113	inode->i_size = OFFSET_MAX;
2114	inode->i_mapping->a_ops = &btree_aops;
2115
2116	RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
2117	extent_io_tree_init(fs_info, &BTRFS_I(inode)->io_tree,
2118			    IO_TREE_INODE_IO, inode);
2119	BTRFS_I(inode)->io_tree.track_uptodate = false;
2120	extent_map_tree_init(&BTRFS_I(inode)->extent_tree);
2121
2122	BTRFS_I(inode)->io_tree.ops = &btree_extent_io_ops;
2123
2124	BTRFS_I(inode)->root = fs_info->tree_root;
2125	memset(&BTRFS_I(inode)->location, 0, sizeof(struct btrfs_key));
2126	set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
2127	btrfs_insert_inode_hash(inode);
2128}
2129
2130static void btrfs_init_dev_replace_locks(struct btrfs_fs_info *fs_info)
2131{
2132	mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount);
2133	init_rwsem(&fs_info->dev_replace.rwsem);
2134	init_waitqueue_head(&fs_info->dev_replace.replace_wait);
2135}
2136
2137static void btrfs_init_qgroup(struct btrfs_fs_info *fs_info)
2138{
2139	spin_lock_init(&fs_info->qgroup_lock);
2140	mutex_init(&fs_info->qgroup_ioctl_lock);
2141	fs_info->qgroup_tree = RB_ROOT;
2142	INIT_LIST_HEAD(&fs_info->dirty_qgroups);
2143	fs_info->qgroup_seq = 1;
2144	fs_info->qgroup_ulist = NULL;
2145	fs_info->qgroup_rescan_running = false;
 
2146	mutex_init(&fs_info->qgroup_rescan_lock);
2147}
2148
2149static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info,
2150		struct btrfs_fs_devices *fs_devices)
2151{
2152	u32 max_active = fs_info->thread_pool_size;
2153	unsigned int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND;
2154
2155	fs_info->workers =
2156		btrfs_alloc_workqueue(fs_info, "worker",
 
 
2157				      flags | WQ_HIGHPRI, max_active, 16);
2158
2159	fs_info->delalloc_workers =
2160		btrfs_alloc_workqueue(fs_info, "delalloc",
2161				      flags, max_active, 2);
2162
2163	fs_info->flush_workers =
2164		btrfs_alloc_workqueue(fs_info, "flush_delalloc",
2165				      flags, max_active, 0);
2166
2167	fs_info->caching_workers =
2168		btrfs_alloc_workqueue(fs_info, "cache", flags, max_active, 0);
2169
2170	/*
2171	 * a higher idle thresh on the submit workers makes it much more
2172	 * likely that bios will be send down in a sane order to the
2173	 * devices
2174	 */
2175	fs_info->submit_workers =
2176		btrfs_alloc_workqueue(fs_info, "submit", flags,
2177				      min_t(u64, fs_devices->num_devices,
2178					    max_active), 64);
2179
2180	fs_info->fixup_workers =
2181		btrfs_alloc_workqueue(fs_info, "fixup", flags, 1, 0);
2182
2183	/*
2184	 * endios are largely parallel and should have a very
2185	 * low idle thresh
2186	 */
2187	fs_info->endio_workers =
2188		btrfs_alloc_workqueue(fs_info, "endio", flags, max_active, 4);
2189	fs_info->endio_meta_workers =
2190		btrfs_alloc_workqueue(fs_info, "endio-meta", flags,
2191				      max_active, 4);
2192	fs_info->endio_meta_write_workers =
2193		btrfs_alloc_workqueue(fs_info, "endio-meta-write", flags,
2194				      max_active, 2);
2195	fs_info->endio_raid56_workers =
2196		btrfs_alloc_workqueue(fs_info, "endio-raid56", flags,
2197				      max_active, 4);
2198	fs_info->endio_repair_workers =
2199		btrfs_alloc_workqueue(fs_info, "endio-repair", flags, 1, 0);
2200	fs_info->rmw_workers =
2201		btrfs_alloc_workqueue(fs_info, "rmw", flags, max_active, 2);
2202	fs_info->endio_write_workers =
2203		btrfs_alloc_workqueue(fs_info, "endio-write", flags,
2204				      max_active, 2);
 
 
2205	fs_info->endio_freespace_worker =
2206		btrfs_alloc_workqueue(fs_info, "freespace-write", flags,
2207				      max_active, 0);
2208	fs_info->delayed_workers =
2209		btrfs_alloc_workqueue(fs_info, "delayed-meta", flags,
2210				      max_active, 0);
2211	fs_info->readahead_workers =
2212		btrfs_alloc_workqueue(fs_info, "readahead", flags,
2213				      max_active, 2);
2214	fs_info->qgroup_rescan_workers =
2215		btrfs_alloc_workqueue(fs_info, "qgroup-rescan", flags, 1, 0);
 
 
2216
2217	if (!(fs_info->workers && fs_info->delalloc_workers &&
2218	      fs_info->submit_workers && fs_info->flush_workers &&
2219	      fs_info->endio_workers && fs_info->endio_meta_workers &&
2220	      fs_info->endio_meta_write_workers &&
2221	      fs_info->endio_repair_workers &&
2222	      fs_info->endio_write_workers && fs_info->endio_raid56_workers &&
2223	      fs_info->endio_freespace_worker && fs_info->rmw_workers &&
2224	      fs_info->caching_workers && fs_info->readahead_workers &&
2225	      fs_info->fixup_workers && fs_info->delayed_workers &&
2226	      fs_info->qgroup_rescan_workers)) {
2227		return -ENOMEM;
2228	}
2229
2230	return 0;
2231}
2232
2233static int btrfs_init_csum_hash(struct btrfs_fs_info *fs_info, u16 csum_type)
2234{
2235	struct crypto_shash *csum_shash;
2236	const char *csum_name = btrfs_super_csum_name(csum_type);
2237
2238	csum_shash = crypto_alloc_shash(csum_name, 0, 0);
2239
2240	if (IS_ERR(csum_shash)) {
2241		btrfs_err(fs_info, "error allocating %s hash for checksum",
2242			  csum_name);
2243		return PTR_ERR(csum_shash);
2244	}
2245
2246	fs_info->csum_shash = csum_shash;
2247
 
 
 
2248	return 0;
2249}
2250
2251static void btrfs_free_csum_hash(struct btrfs_fs_info *fs_info)
2252{
2253	crypto_free_shash(fs_info->csum_shash);
2254}
2255
2256static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
2257			    struct btrfs_fs_devices *fs_devices)
2258{
2259	int ret;
 
2260	struct btrfs_root *log_tree_root;
2261	struct btrfs_super_block *disk_super = fs_info->super_copy;
2262	u64 bytenr = btrfs_super_log_root(disk_super);
2263	int level = btrfs_super_log_root_level(disk_super);
2264
2265	if (fs_devices->rw_devices == 0) {
2266		btrfs_warn(fs_info, "log replay required on RO media");
2267		return -EIO;
2268	}
2269
2270	log_tree_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
 
2271	if (!log_tree_root)
2272		return -ENOMEM;
2273
2274	__setup_root(log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
2275
2276	log_tree_root->node = read_tree_block(fs_info, bytenr,
2277					      fs_info->generation + 1,
2278					      level, NULL);
2279	if (IS_ERR(log_tree_root->node)) {
2280		btrfs_warn(fs_info, "failed to read log tree");
2281		ret = PTR_ERR(log_tree_root->node);
2282		kfree(log_tree_root);
 
2283		return ret;
2284	} else if (!extent_buffer_uptodate(log_tree_root->node)) {
 
2285		btrfs_err(fs_info, "failed to read log tree");
2286		free_extent_buffer(log_tree_root->node);
2287		kfree(log_tree_root);
2288		return -EIO;
2289	}
 
2290	/* returns with log_tree_root freed on success */
2291	ret = btrfs_recover_log_trees(log_tree_root);
2292	if (ret) {
2293		btrfs_handle_fs_error(fs_info, ret,
2294				      "Failed to recover log tree");
2295		free_extent_buffer(log_tree_root->node);
2296		kfree(log_tree_root);
2297		return ret;
2298	}
2299
2300	if (sb_rdonly(fs_info->sb)) {
2301		ret = btrfs_commit_super(fs_info);
2302		if (ret)
2303			return ret;
2304	}
2305
2306	return 0;
2307}
2308
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2309static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
2310{
2311	struct btrfs_root *tree_root = fs_info->tree_root;
2312	struct btrfs_root *root;
2313	struct btrfs_key location;
2314	int ret;
2315
2316	BUG_ON(!fs_info->tree_root);
2317
2318	location.objectid = BTRFS_EXTENT_TREE_OBJECTID;
 
 
 
2319	location.type = BTRFS_ROOT_ITEM_KEY;
2320	location.offset = 0;
2321
2322	root = btrfs_read_tree_root(tree_root, &location);
2323	if (IS_ERR(root)) {
2324		ret = PTR_ERR(root);
2325		goto out;
 
 
 
 
 
 
 
 
2326	}
2327	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2328	fs_info->extent_root = root;
2329
2330	location.objectid = BTRFS_DEV_TREE_OBJECTID;
2331	root = btrfs_read_tree_root(tree_root, &location);
2332	if (IS_ERR(root)) {
2333		ret = PTR_ERR(root);
2334		goto out;
 
 
 
 
 
2335	}
2336	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2337	fs_info->dev_root = root;
2338	btrfs_init_devices_late(fs_info);
 
2339
2340	location.objectid = BTRFS_CSUM_TREE_OBJECTID;
2341	root = btrfs_read_tree_root(tree_root, &location);
 
 
 
 
2342	if (IS_ERR(root)) {
2343		ret = PTR_ERR(root);
2344		goto out;
 
 
 
 
 
2345	}
2346	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2347	fs_info->csum_root = root;
2348
2349	location.objectid = BTRFS_QUOTA_TREE_OBJECTID;
2350	root = btrfs_read_tree_root(tree_root, &location);
2351	if (!IS_ERR(root)) {
2352		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2353		set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
2354		fs_info->quota_root = root;
2355	}
2356
2357	location.objectid = BTRFS_UUID_TREE_OBJECTID;
2358	root = btrfs_read_tree_root(tree_root, &location);
2359	if (IS_ERR(root)) {
2360		ret = PTR_ERR(root);
2361		if (ret != -ENOENT)
2362			goto out;
2363	} else {
2364		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2365		fs_info->uuid_root = root;
2366	}
2367
2368	if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
2369		location.objectid = BTRFS_FREE_SPACE_TREE_OBJECTID;
2370		root = btrfs_read_tree_root(tree_root, &location);
2371		if (IS_ERR(root)) {
2372			ret = PTR_ERR(root);
2373			goto out;
 
2374		}
 
2375		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2376		fs_info->free_space_root = root;
2377	}
2378
2379	return 0;
2380out:
2381	btrfs_warn(fs_info, "failed to read root (objectid=%llu): %d",
2382		   location.objectid, ret);
2383	return ret;
2384}
2385
2386/*
2387 * Real super block validation
2388 * NOTE: super csum type and incompat features will not be checked here.
2389 *
2390 * @sb:		super block to check
2391 * @mirror_num:	the super block number to check its bytenr:
2392 * 		0	the primary (1st) sb
2393 * 		1, 2	2nd and 3rd backup copy
2394 * 	       -1	skip bytenr check
2395 */
2396static int validate_super(struct btrfs_fs_info *fs_info,
2397			    struct btrfs_super_block *sb, int mirror_num)
2398{
2399	u64 nodesize = btrfs_super_nodesize(sb);
2400	u64 sectorsize = btrfs_super_sectorsize(sb);
2401	int ret = 0;
2402
2403	if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
2404		btrfs_err(fs_info, "no valid FS found");
2405		ret = -EINVAL;
2406	}
2407	if (btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP) {
2408		btrfs_err(fs_info, "unrecognized or unsupported super flag: %llu",
2409				btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);
2410		ret = -EINVAL;
2411	}
2412	if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
2413		btrfs_err(fs_info, "tree_root level too big: %d >= %d",
2414				btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
2415		ret = -EINVAL;
2416	}
2417	if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
2418		btrfs_err(fs_info, "chunk_root level too big: %d >= %d",
2419				btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
2420		ret = -EINVAL;
2421	}
2422	if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
2423		btrfs_err(fs_info, "log_root level too big: %d >= %d",
2424				btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
2425		ret = -EINVAL;
2426	}
2427
2428	/*
2429	 * Check sectorsize and nodesize first, other check will need it.
2430	 * Check all possible sectorsize(4K, 8K, 16K, 32K, 64K) here.
2431	 */
2432	if (!is_power_of_2(sectorsize) || sectorsize < 4096 ||
2433	    sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2434		btrfs_err(fs_info, "invalid sectorsize %llu", sectorsize);
2435		ret = -EINVAL;
2436	}
2437	/* Only PAGE SIZE is supported yet */
2438	if (sectorsize != PAGE_SIZE) {
 
 
 
 
 
 
 
 
2439		btrfs_err(fs_info,
2440			"sectorsize %llu not supported yet, only support %lu",
2441			sectorsize, PAGE_SIZE);
2442		ret = -EINVAL;
2443	}
 
2444	if (!is_power_of_2(nodesize) || nodesize < sectorsize ||
2445	    nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2446		btrfs_err(fs_info, "invalid nodesize %llu", nodesize);
2447		ret = -EINVAL;
2448	}
2449	if (nodesize != le32_to_cpu(sb->__unused_leafsize)) {
2450		btrfs_err(fs_info, "invalid leafsize %u, should be %llu",
2451			  le32_to_cpu(sb->__unused_leafsize), nodesize);
2452		ret = -EINVAL;
2453	}
2454
2455	/* Root alignment check */
2456	if (!IS_ALIGNED(btrfs_super_root(sb), sectorsize)) {
2457		btrfs_warn(fs_info, "tree_root block unaligned: %llu",
2458			   btrfs_super_root(sb));
2459		ret = -EINVAL;
2460	}
2461	if (!IS_ALIGNED(btrfs_super_chunk_root(sb), sectorsize)) {
2462		btrfs_warn(fs_info, "chunk_root block unaligned: %llu",
2463			   btrfs_super_chunk_root(sb));
2464		ret = -EINVAL;
2465	}
2466	if (!IS_ALIGNED(btrfs_super_log_root(sb), sectorsize)) {
2467		btrfs_warn(fs_info, "log_root block unaligned: %llu",
2468			   btrfs_super_log_root(sb));
2469		ret = -EINVAL;
2470	}
2471
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2472	if (memcmp(fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid,
2473		   BTRFS_FSID_SIZE) != 0) {
2474		btrfs_err(fs_info,
2475			"dev_item UUID does not match metadata fsid: %pU != %pU",
2476			fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid);
2477		ret = -EINVAL;
2478	}
2479
2480	/*
2481	 * Hint to catch really bogus numbers, bitflips or so, more exact checks are
2482	 * done later
2483	 */
2484	if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) {
2485		btrfs_err(fs_info, "bytes_used is too small %llu",
2486			  btrfs_super_bytes_used(sb));
2487		ret = -EINVAL;
2488	}
2489	if (!is_power_of_2(btrfs_super_stripesize(sb))) {
2490		btrfs_err(fs_info, "invalid stripesize %u",
2491			  btrfs_super_stripesize(sb));
2492		ret = -EINVAL;
2493	}
2494	if (btrfs_super_num_devices(sb) > (1UL << 31))
2495		btrfs_warn(fs_info, "suspicious number of devices: %llu",
2496			   btrfs_super_num_devices(sb));
2497	if (btrfs_super_num_devices(sb) == 0) {
2498		btrfs_err(fs_info, "number of devices is 0");
2499		ret = -EINVAL;
2500	}
2501
2502	if (mirror_num >= 0 &&
2503	    btrfs_super_bytenr(sb) != btrfs_sb_offset(mirror_num)) {
2504		btrfs_err(fs_info, "super offset mismatch %llu != %u",
2505			  btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET);
2506		ret = -EINVAL;
2507	}
2508
2509	/*
2510	 * Obvious sys_chunk_array corruptions, it must hold at least one key
2511	 * and one chunk
2512	 */
2513	if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
2514		btrfs_err(fs_info, "system chunk array too big %u > %u",
2515			  btrfs_super_sys_array_size(sb),
2516			  BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
2517		ret = -EINVAL;
2518	}
2519	if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
2520			+ sizeof(struct btrfs_chunk)) {
2521		btrfs_err(fs_info, "system chunk array too small %u < %zu",
2522			  btrfs_super_sys_array_size(sb),
2523			  sizeof(struct btrfs_disk_key)
2524			  + sizeof(struct btrfs_chunk));
2525		ret = -EINVAL;
2526	}
2527
2528	/*
2529	 * The generation is a global counter, we'll trust it more than the others
2530	 * but it's still possible that it's the one that's wrong.
2531	 */
2532	if (btrfs_super_generation(sb) < btrfs_super_chunk_root_generation(sb))
2533		btrfs_warn(fs_info,
2534			"suspicious: generation < chunk_root_generation: %llu < %llu",
2535			btrfs_super_generation(sb),
2536			btrfs_super_chunk_root_generation(sb));
2537	if (btrfs_super_generation(sb) < btrfs_super_cache_generation(sb)
2538	    && btrfs_super_cache_generation(sb) != (u64)-1)
2539		btrfs_warn(fs_info,
2540			"suspicious: generation < cache_generation: %llu < %llu",
2541			btrfs_super_generation(sb),
2542			btrfs_super_cache_generation(sb));
2543
2544	return ret;
2545}
2546
2547/*
2548 * Validation of super block at mount time.
2549 * Some checks already done early at mount time, like csum type and incompat
2550 * flags will be skipped.
2551 */
2552static int btrfs_validate_mount_super(struct btrfs_fs_info *fs_info)
2553{
2554	return validate_super(fs_info, fs_info->super_copy, 0);
2555}
2556
2557/*
2558 * Validation of super block at write time.
2559 * Some checks like bytenr check will be skipped as their values will be
2560 * overwritten soon.
2561 * Extra checks like csum type and incompat flags will be done here.
2562 */
2563static int btrfs_validate_write_super(struct btrfs_fs_info *fs_info,
2564				      struct btrfs_super_block *sb)
2565{
2566	int ret;
2567
2568	ret = validate_super(fs_info, sb, -1);
2569	if (ret < 0)
2570		goto out;
2571	if (!btrfs_supported_super_csum(btrfs_super_csum_type(sb))) {
2572		ret = -EUCLEAN;
2573		btrfs_err(fs_info, "invalid csum type, has %u want %u",
2574			  btrfs_super_csum_type(sb), BTRFS_CSUM_TYPE_CRC32);
2575		goto out;
2576	}
2577	if (btrfs_super_incompat_flags(sb) & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
2578		ret = -EUCLEAN;
2579		btrfs_err(fs_info,
2580		"invalid incompat flags, has 0x%llx valid mask 0x%llx",
2581			  btrfs_super_incompat_flags(sb),
2582			  (unsigned long long)BTRFS_FEATURE_INCOMPAT_SUPP);
2583		goto out;
2584	}
2585out:
2586	if (ret < 0)
2587		btrfs_err(fs_info,
2588		"super block corruption detected before writing it to disk");
2589	return ret;
2590}
2591
2592int open_ctree(struct super_block *sb,
2593	       struct btrfs_fs_devices *fs_devices,
2594	       char *options)
2595{
2596	u32 sectorsize;
2597	u32 nodesize;
2598	u32 stripesize;
2599	u64 generation;
2600	u64 features;
2601	u16 csum_type;
2602	struct btrfs_key location;
2603	struct buffer_head *bh;
2604	struct btrfs_super_block *disk_super;
2605	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
2606	struct btrfs_root *tree_root;
2607	struct btrfs_root *chunk_root;
2608	int ret;
2609	int err = -EINVAL;
2610	int num_backups_tried = 0;
2611	int backup_index = 0;
2612	int clear_free_space_tree = 0;
2613	int level;
2614
2615	tree_root = fs_info->tree_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
2616	chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
2617	if (!tree_root || !chunk_root) {
2618		err = -ENOMEM;
2619		goto fail;
2620	}
2621
2622	ret = init_srcu_struct(&fs_info->subvol_srcu);
2623	if (ret) {
2624		err = ret;
2625		goto fail;
2626	}
2627
2628	ret = percpu_counter_init(&fs_info->dio_bytes, 0, GFP_KERNEL);
2629	if (ret) {
2630		err = ret;
2631		goto fail_srcu;
2632	}
2633
2634	ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0, GFP_KERNEL);
 
 
 
 
 
 
 
 
 
2635	if (ret) {
2636		err = ret;
2637		goto fail_dio_bytes;
2638	}
2639	fs_info->dirty_metadata_batch = PAGE_SIZE *
2640					(1 + ilog2(nr_cpu_ids));
2641
2642	ret = percpu_counter_init(&fs_info->delalloc_bytes, 0, GFP_KERNEL);
2643	if (ret) {
2644		err = ret;
2645		goto fail_dirty_metadata_bytes;
2646	}
 
 
 
2647
2648	ret = percpu_counter_init(&fs_info->dev_replace.bio_counter, 0,
2649			GFP_KERNEL);
2650	if (ret) {
2651		err = ret;
2652		goto fail_delalloc_bytes;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2653	}
2654
 
 
 
 
 
2655	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
2656	INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC);
2657	INIT_LIST_HEAD(&fs_info->trans_list);
2658	INIT_LIST_HEAD(&fs_info->dead_roots);
2659	INIT_LIST_HEAD(&fs_info->delayed_iputs);
2660	INIT_LIST_HEAD(&fs_info->delalloc_roots);
2661	INIT_LIST_HEAD(&fs_info->caching_block_groups);
2662	spin_lock_init(&fs_info->delalloc_root_lock);
2663	spin_lock_init(&fs_info->trans_lock);
2664	spin_lock_init(&fs_info->fs_roots_radix_lock);
2665	spin_lock_init(&fs_info->delayed_iput_lock);
2666	spin_lock_init(&fs_info->defrag_inodes_lock);
2667	spin_lock_init(&fs_info->tree_mod_seq_lock);
2668	spin_lock_init(&fs_info->super_lock);
2669	spin_lock_init(&fs_info->buffer_lock);
2670	spin_lock_init(&fs_info->unused_bgs_lock);
 
 
 
2671	rwlock_init(&fs_info->tree_mod_log_lock);
 
2672	mutex_init(&fs_info->unused_bg_unpin_mutex);
2673	mutex_init(&fs_info->delete_unused_bgs_mutex);
2674	mutex_init(&fs_info->reloc_mutex);
2675	mutex_init(&fs_info->delalloc_root_mutex);
 
 
2676	seqlock_init(&fs_info->profiles_lock);
2677
 
 
 
 
 
 
 
 
 
 
 
 
 
2678	INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
2679	INIT_LIST_HEAD(&fs_info->space_info);
2680	INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
2681	INIT_LIST_HEAD(&fs_info->unused_bgs);
 
 
 
 
 
 
 
2682	extent_map_tree_init(&fs_info->mapping_tree);
2683	btrfs_init_block_rsv(&fs_info->global_block_rsv,
2684			     BTRFS_BLOCK_RSV_GLOBAL);
2685	btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
2686	btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK);
2687	btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY);
2688	btrfs_init_block_rsv(&fs_info->delayed_block_rsv,
2689			     BTRFS_BLOCK_RSV_DELOPS);
2690	btrfs_init_block_rsv(&fs_info->delayed_refs_rsv,
2691			     BTRFS_BLOCK_RSV_DELREFS);
2692
2693	atomic_set(&fs_info->async_delalloc_pages, 0);
2694	atomic_set(&fs_info->defrag_running, 0);
2695	atomic_set(&fs_info->reada_works_cnt, 0);
2696	atomic_set(&fs_info->nr_delayed_iputs, 0);
2697	atomic64_set(&fs_info->tree_mod_seq, 0);
2698	fs_info->sb = sb;
2699	fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE;
2700	fs_info->metadata_ratio = 0;
2701	fs_info->defrag_inodes = RB_ROOT;
2702	atomic64_set(&fs_info->free_chunk_space, 0);
2703	fs_info->tree_mod_log = RB_ROOT;
2704	fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
2705	fs_info->avg_delayed_ref_runtime = NSEC_PER_SEC >> 6; /* div by 64 */
2706	/* readahead state */
2707	INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
2708	spin_lock_init(&fs_info->reada_lock);
2709	btrfs_init_ref_verify(fs_info);
2710
2711	fs_info->thread_pool_size = min_t(unsigned long,
2712					  num_online_cpus() + 2, 8);
2713
2714	INIT_LIST_HEAD(&fs_info->ordered_roots);
2715	spin_lock_init(&fs_info->ordered_root_lock);
2716
2717	fs_info->btree_inode = new_inode(sb);
2718	if (!fs_info->btree_inode) {
2719		err = -ENOMEM;
2720		goto fail_bio_counter;
2721	}
2722	mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
2723
2724	fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
2725					GFP_KERNEL);
2726	if (!fs_info->delayed_root) {
2727		err = -ENOMEM;
2728		goto fail_iput;
2729	}
2730	btrfs_init_delayed_root(fs_info->delayed_root);
2731
2732	btrfs_init_scrub(fs_info);
2733#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
2734	fs_info->check_integrity_print_mask = 0;
2735#endif
2736	btrfs_init_balance(fs_info);
2737	btrfs_init_async_reclaim_work(&fs_info->async_reclaim_work);
2738
2739	sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE;
2740	sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE);
2741
2742	btrfs_init_btree_inode(fs_info);
 
2743
2744	spin_lock_init(&fs_info->block_group_cache_lock);
2745	fs_info->block_group_cache_tree = RB_ROOT;
2746	fs_info->first_logical_byte = (u64)-1;
2747
2748	extent_io_tree_init(fs_info, &fs_info->freed_extents[0],
2749			    IO_TREE_FS_INFO_FREED_EXTENTS0, NULL);
2750	extent_io_tree_init(fs_info, &fs_info->freed_extents[1],
2751			    IO_TREE_FS_INFO_FREED_EXTENTS1, NULL);
2752	fs_info->pinned_extents = &fs_info->freed_extents[0];
2753	set_bit(BTRFS_FS_BARRIER, &fs_info->flags);
2754
2755	mutex_init(&fs_info->ordered_operations_mutex);
2756	mutex_init(&fs_info->tree_log_mutex);
2757	mutex_init(&fs_info->chunk_mutex);
2758	mutex_init(&fs_info->transaction_kthread_mutex);
2759	mutex_init(&fs_info->cleaner_mutex);
2760	mutex_init(&fs_info->ro_block_group_mutex);
2761	init_rwsem(&fs_info->commit_root_sem);
2762	init_rwsem(&fs_info->cleanup_work_sem);
2763	init_rwsem(&fs_info->subvol_sem);
2764	sema_init(&fs_info->uuid_tree_rescan_sem, 1);
2765
2766	btrfs_init_dev_replace_locks(fs_info);
2767	btrfs_init_qgroup(fs_info);
 
2768
2769	btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
2770	btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
2771
2772	init_waitqueue_head(&fs_info->transaction_throttle);
2773	init_waitqueue_head(&fs_info->transaction_wait);
2774	init_waitqueue_head(&fs_info->transaction_blocked_wait);
2775	init_waitqueue_head(&fs_info->async_submit_wait);
2776	init_waitqueue_head(&fs_info->delayed_iputs_wait);
2777
2778	/* Usable values until the real ones are cached from the superblock */
2779	fs_info->nodesize = 4096;
2780	fs_info->sectorsize = 4096;
 
2781	fs_info->stripesize = 4096;
2782
 
 
2783	spin_lock_init(&fs_info->swapfile_pins_lock);
2784	fs_info->swapfile_pins = RB_ROOT;
2785
2786	fs_info->send_in_progress = 0;
 
 
2787
2788	ret = btrfs_alloc_stripe_hash_table(fs_info);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2789	if (ret) {
2790		err = ret;
2791		goto fail_alloc;
2792	}
2793
2794	__setup_root(tree_root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
 
 
 
 
 
 
 
 
 
 
2795
2796	invalidate_bdev(fs_devices->latest_bdev);
 
 
 
 
 
 
 
 
2797
2798	/*
2799	 * Read super block and check the signature bytes only
2800	 */
2801	bh = btrfs_read_dev_super(fs_devices->latest_bdev);
2802	if (IS_ERR(bh)) {
2803		err = PTR_ERR(bh);
2804		goto fail_alloc;
2805	}
2806
2807	/*
2808	 * Verify the type first, if that or the the checksum value are
2809	 * corrupted, we'll find out
2810	 */
2811	csum_type = btrfs_super_csum_type((struct btrfs_super_block *)bh->b_data);
2812	if (!btrfs_supported_super_csum(csum_type)) {
2813		btrfs_err(fs_info, "unsupported checksum algorithm: %u",
2814			  csum_type);
2815		err = -EINVAL;
2816		brelse(bh);
2817		goto fail_alloc;
2818	}
2819
 
 
2820	ret = btrfs_init_csum_hash(fs_info, csum_type);
2821	if (ret) {
2822		err = ret;
 
2823		goto fail_alloc;
2824	}
2825
2826	/*
2827	 * We want to check superblock checksum, the type is stored inside.
2828	 * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k).
2829	 */
2830	if (btrfs_check_super_csum(fs_info, bh->b_data)) {
2831		btrfs_err(fs_info, "superblock checksum mismatch");
2832		err = -EINVAL;
2833		brelse(bh);
2834		goto fail_csum;
2835	}
2836
2837	/*
2838	 * super_copy is zeroed at allocation time and we never touch the
2839	 * following bytes up to INFO_SIZE, the checksum is calculated from
2840	 * the whole block of INFO_SIZE
2841	 */
2842	memcpy(fs_info->super_copy, bh->b_data, sizeof(*fs_info->super_copy));
2843	brelse(bh);
2844
2845	disk_super = fs_info->super_copy;
2846
2847	ASSERT(!memcmp(fs_info->fs_devices->fsid, fs_info->super_copy->fsid,
2848		       BTRFS_FSID_SIZE));
2849
2850	if (btrfs_fs_incompat(fs_info, METADATA_UUID)) {
2851		ASSERT(!memcmp(fs_info->fs_devices->metadata_uuid,
2852				fs_info->super_copy->metadata_uuid,
2853				BTRFS_FSID_SIZE));
2854	}
2855
2856	features = btrfs_super_flags(disk_super);
2857	if (features & BTRFS_SUPER_FLAG_CHANGING_FSID_V2) {
2858		features &= ~BTRFS_SUPER_FLAG_CHANGING_FSID_V2;
2859		btrfs_set_super_flags(disk_super, features);
2860		btrfs_info(fs_info,
2861			"found metadata UUID change in progress flag, clearing");
2862	}
2863
2864	memcpy(fs_info->super_for_commit, fs_info->super_copy,
2865	       sizeof(*fs_info->super_for_commit));
2866
2867	ret = btrfs_validate_mount_super(fs_info);
2868	if (ret) {
2869		btrfs_err(fs_info, "superblock contains fatal errors");
2870		err = -EINVAL;
2871		goto fail_csum;
2872	}
2873
2874	if (!btrfs_super_root(disk_super))
2875		goto fail_csum;
2876
2877	/* check FS state, whether FS is broken. */
2878	if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
2879		set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state);
2880
2881	/*
2882	 * run through our array of backup supers and setup
2883	 * our ring pointer to the oldest one
2884	 */
2885	generation = btrfs_super_generation(disk_super);
2886	find_oldest_super_backup(fs_info, generation);
2887
2888	/*
2889	 * In the long term, we'll store the compression type in the super
2890	 * block, and it'll be used for per file compression control.
2891	 */
2892	fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
2893
2894	ret = btrfs_parse_options(fs_info, options, sb->s_flags);
2895	if (ret) {
2896		err = ret;
2897		goto fail_csum;
2898	}
2899
2900	features = btrfs_super_incompat_flags(disk_super) &
2901		~BTRFS_FEATURE_INCOMPAT_SUPP;
2902	if (features) {
2903		btrfs_err(fs_info,
2904		    "cannot mount because of unsupported optional features (%llx)",
2905		    features);
2906		err = -EINVAL;
2907		goto fail_csum;
2908	}
2909
2910	features = btrfs_super_incompat_flags(disk_super);
2911	features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
2912	if (fs_info->compress_type == BTRFS_COMPRESS_LZO)
2913		features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
2914	else if (fs_info->compress_type == BTRFS_COMPRESS_ZSTD)
2915		features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD;
2916
2917	if (features & BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA)
2918		btrfs_info(fs_info, "has skinny extents");
2919
2920	/*
2921	 * flag our filesystem as having big metadata blocks if
2922	 * they are bigger than the page size
2923	 */
2924	if (btrfs_super_nodesize(disk_super) > PAGE_SIZE) {
2925		if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA))
2926			btrfs_info(fs_info,
2927				"flagging fs with big metadata feature");
2928		features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
2929	}
2930
 
2931	nodesize = btrfs_super_nodesize(disk_super);
2932	sectorsize = btrfs_super_sectorsize(disk_super);
2933	stripesize = sectorsize;
2934	fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids));
2935	fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
2936
2937	/* Cache block sizes */
2938	fs_info->nodesize = nodesize;
2939	fs_info->sectorsize = sectorsize;
 
 
2940	fs_info->stripesize = stripesize;
2941
2942	/*
2943	 * mixed block groups end up with duplicate but slightly offset
2944	 * extent buffers for the same range.  It leads to corruptions
2945	 */
2946	if ((features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
2947	    (sectorsize != nodesize)) {
2948		btrfs_err(fs_info,
2949"unequal nodesize/sectorsize (%u != %u) are not allowed for mixed block groups",
2950			nodesize, sectorsize);
2951		goto fail_csum;
2952	}
2953
2954	/*
2955	 * Needn't use the lock because there is no other task which will
2956	 * update the flag.
2957	 */
2958	btrfs_set_super_incompat_flags(disk_super, features);
2959
2960	features = btrfs_super_compat_ro_flags(disk_super) &
2961		~BTRFS_FEATURE_COMPAT_RO_SUPP;
2962	if (!sb_rdonly(sb) && features) {
2963		btrfs_err(fs_info,
2964	"cannot mount read-write because of unsupported optional features (%llx)",
2965		       features);
2966		err = -EINVAL;
2967		goto fail_csum;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2968	}
2969
2970	ret = btrfs_init_workqueues(fs_info, fs_devices);
2971	if (ret) {
2972		err = ret;
2973		goto fail_sb_buffer;
2974	}
2975
2976	sb->s_bdi->congested_fn = btrfs_congested_fn;
2977	sb->s_bdi->congested_data = fs_info;
2978	sb->s_bdi->capabilities |= BDI_CAP_CGROUP_WRITEBACK;
2979	sb->s_bdi->ra_pages = VM_READAHEAD_PAGES;
2980	sb->s_bdi->ra_pages *= btrfs_super_num_devices(disk_super);
2981	sb->s_bdi->ra_pages = max(sb->s_bdi->ra_pages, SZ_4M / PAGE_SIZE);
2982
2983	sb->s_blocksize = sectorsize;
2984	sb->s_blocksize_bits = blksize_bits(sectorsize);
2985	memcpy(&sb->s_uuid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE);
2986
2987	mutex_lock(&fs_info->chunk_mutex);
2988	ret = btrfs_read_sys_array(fs_info);
2989	mutex_unlock(&fs_info->chunk_mutex);
2990	if (ret) {
2991		btrfs_err(fs_info, "failed to read the system array: %d", ret);
2992		goto fail_sb_buffer;
2993	}
2994
2995	generation = btrfs_super_chunk_root_generation(disk_super);
2996	level = btrfs_super_chunk_root_level(disk_super);
2997
2998	__setup_root(chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
2999
3000	chunk_root->node = read_tree_block(fs_info,
3001					   btrfs_super_chunk_root(disk_super),
3002					   generation, level, NULL);
3003	if (IS_ERR(chunk_root->node) ||
3004	    !extent_buffer_uptodate(chunk_root->node)) {
3005		btrfs_err(fs_info, "failed to read chunk root");
3006		if (!IS_ERR(chunk_root->node))
3007			free_extent_buffer(chunk_root->node);
3008		chunk_root->node = NULL;
3009		goto fail_tree_roots;
3010	}
3011	btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
3012	chunk_root->commit_root = btrfs_root_node(chunk_root);
3013
3014	read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
3015	   btrfs_header_chunk_tree_uuid(chunk_root->node), BTRFS_UUID_SIZE);
 
3016
3017	ret = btrfs_read_chunk_tree(fs_info);
3018	if (ret) {
3019		btrfs_err(fs_info, "failed to read chunk tree: %d", ret);
3020		goto fail_tree_roots;
3021	}
3022
3023	/*
3024	 * Keep the devid that is marked to be the target device for the
3025	 * device replace procedure
 
 
 
3026	 */
3027	btrfs_free_extra_devids(fs_devices, 0);
3028
3029	if (!fs_devices->latest_bdev) {
3030		btrfs_err(fs_info, "failed to read devices");
3031		goto fail_tree_roots;
3032	}
3033
3034retry_root_backup:
3035	generation = btrfs_super_generation(disk_super);
3036	level = btrfs_super_root_level(disk_super);
3037
3038	tree_root->node = read_tree_block(fs_info,
3039					  btrfs_super_root(disk_super),
3040					  generation, level, NULL);
3041	if (IS_ERR(tree_root->node) ||
3042	    !extent_buffer_uptodate(tree_root->node)) {
3043		btrfs_warn(fs_info, "failed to read tree root");
3044		if (!IS_ERR(tree_root->node))
3045			free_extent_buffer(tree_root->node);
3046		tree_root->node = NULL;
3047		goto recovery_tree_root;
3048	}
3049
3050	btrfs_set_root_node(&tree_root->root_item, tree_root->node);
3051	tree_root->commit_root = btrfs_root_node(tree_root);
3052	btrfs_set_root_refs(&tree_root->root_item, 1);
3053
3054	mutex_lock(&tree_root->objectid_mutex);
3055	ret = btrfs_find_highest_objectid(tree_root,
3056					&tree_root->highest_objectid);
3057	if (ret) {
3058		mutex_unlock(&tree_root->objectid_mutex);
3059		goto recovery_tree_root;
 
 
3060	}
3061
3062	ASSERT(tree_root->highest_objectid <= BTRFS_LAST_FREE_OBJECTID);
3063
3064	mutex_unlock(&tree_root->objectid_mutex);
3065
3066	ret = btrfs_read_roots(fs_info);
3067	if (ret)
3068		goto recovery_tree_root;
3069
3070	fs_info->generation = generation;
3071	fs_info->last_trans_committed = generation;
 
3072
3073	ret = btrfs_verify_dev_extents(fs_info);
3074	if (ret) {
3075		btrfs_err(fs_info,
3076			  "failed to verify dev extents against chunks: %d",
3077			  ret);
3078		goto fail_block_groups;
3079	}
3080	ret = btrfs_recover_balance(fs_info);
3081	if (ret) {
3082		btrfs_err(fs_info, "failed to recover balance: %d", ret);
3083		goto fail_block_groups;
3084	}
3085
3086	ret = btrfs_init_dev_stats(fs_info);
3087	if (ret) {
3088		btrfs_err(fs_info, "failed to init dev_stats: %d", ret);
3089		goto fail_block_groups;
3090	}
3091
3092	ret = btrfs_init_dev_replace(fs_info);
3093	if (ret) {
3094		btrfs_err(fs_info, "failed to init dev_replace: %d", ret);
3095		goto fail_block_groups;
3096	}
3097
3098	btrfs_free_extra_devids(fs_devices, 1);
3099
3100	ret = btrfs_sysfs_add_fsid(fs_devices, NULL);
3101	if (ret) {
3102		btrfs_err(fs_info, "failed to init sysfs fsid interface: %d",
3103				ret);
3104		goto fail_block_groups;
3105	}
3106
3107	ret = btrfs_sysfs_add_device(fs_devices);
3108	if (ret) {
3109		btrfs_err(fs_info, "failed to init sysfs device interface: %d",
3110				ret);
3111		goto fail_fsdev_sysfs;
3112	}
3113
3114	ret = btrfs_sysfs_add_mounted(fs_info);
3115	if (ret) {
3116		btrfs_err(fs_info, "failed to init sysfs interface: %d", ret);
3117		goto fail_fsdev_sysfs;
3118	}
3119
3120	ret = btrfs_init_space_info(fs_info);
3121	if (ret) {
3122		btrfs_err(fs_info, "failed to initialize space info: %d", ret);
3123		goto fail_sysfs;
3124	}
3125
3126	ret = btrfs_read_block_groups(fs_info);
3127	if (ret) {
3128		btrfs_err(fs_info, "failed to read block groups: %d", ret);
3129		goto fail_sysfs;
3130	}
3131
3132	if (!sb_rdonly(sb) && !btrfs_check_rw_degradable(fs_info, NULL)) {
 
 
 
3133		btrfs_warn(fs_info,
3134		"writable mount is not allowed due to too many missing devices");
3135		goto fail_sysfs;
3136	}
3137
3138	fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
3139					       "btrfs-cleaner");
3140	if (IS_ERR(fs_info->cleaner_kthread))
3141		goto fail_sysfs;
3142
3143	fs_info->transaction_kthread = kthread_run(transaction_kthread,
3144						   tree_root,
3145						   "btrfs-transaction");
3146	if (IS_ERR(fs_info->transaction_kthread))
3147		goto fail_cleaner;
3148
3149	if (!btrfs_test_opt(fs_info, NOSSD) &&
3150	    !fs_info->fs_devices->rotating) {
3151		btrfs_set_and_info(fs_info, SSD, "enabling ssd optimizations");
3152	}
3153
3154	/*
3155	 * Mount does not set all options immediately, we can do it now and do
3156	 * not have to wait for transaction commit
3157	 */
3158	btrfs_apply_pending_changes(fs_info);
 
 
 
 
 
 
 
 
3159
3160#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3161	if (btrfs_test_opt(fs_info, CHECK_INTEGRITY)) {
3162		ret = btrfsic_mount(fs_info, fs_devices,
3163				    btrfs_test_opt(fs_info,
3164					CHECK_INTEGRITY_INCLUDING_EXTENT_DATA) ?
3165				    1 : 0,
3166				    fs_info->check_integrity_print_mask);
3167		if (ret)
3168			btrfs_warn(fs_info,
3169				"failed to initialize integrity check module: %d",
3170				ret);
3171	}
3172#endif
3173	ret = btrfs_read_qgroup_config(fs_info);
3174	if (ret)
3175		goto fail_trans_kthread;
3176
3177	if (btrfs_build_ref_tree(fs_info))
3178		btrfs_err(fs_info, "couldn't build ref tree");
3179
3180	/* do not make disk changes in broken FS or nologreplay is given */
3181	if (btrfs_super_log_root(disk_super) != 0 &&
3182	    !btrfs_test_opt(fs_info, NOLOGREPLAY)) {
 
3183		ret = btrfs_replay_log(fs_info, fs_devices);
3184		if (ret) {
3185			err = ret;
3186			goto fail_qgroup;
3187		}
3188	}
3189
3190	ret = btrfs_find_orphan_roots(fs_info);
3191	if (ret)
3192		goto fail_qgroup;
3193
3194	if (!sb_rdonly(sb)) {
3195		ret = btrfs_cleanup_fs_roots(fs_info);
3196		if (ret)
3197			goto fail_qgroup;
3198
3199		mutex_lock(&fs_info->cleaner_mutex);
3200		ret = btrfs_recover_relocation(tree_root);
3201		mutex_unlock(&fs_info->cleaner_mutex);
3202		if (ret < 0) {
3203			btrfs_warn(fs_info, "failed to recover relocation: %d",
3204					ret);
3205			err = -EINVAL;
3206			goto fail_qgroup;
3207		}
3208	}
3209
3210	location.objectid = BTRFS_FS_TREE_OBJECTID;
3211	location.type = BTRFS_ROOT_ITEM_KEY;
3212	location.offset = 0;
3213
3214	fs_info->fs_root = btrfs_read_fs_root_no_name(fs_info, &location);
3215	if (IS_ERR(fs_info->fs_root)) {
3216		err = PTR_ERR(fs_info->fs_root);
3217		btrfs_warn(fs_info, "failed to read fs tree: %d", err);
 
3218		goto fail_qgroup;
3219	}
3220
3221	if (sb_rdonly(sb))
3222		return 0;
3223
3224	if (btrfs_test_opt(fs_info, CLEAR_CACHE) &&
3225	    btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3226		clear_free_space_tree = 1;
3227	} else if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
3228		   !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID)) {
3229		btrfs_warn(fs_info, "free space tree is invalid");
3230		clear_free_space_tree = 1;
3231	}
3232
3233	if (clear_free_space_tree) {
3234		btrfs_info(fs_info, "clearing free space tree");
3235		ret = btrfs_clear_free_space_tree(fs_info);
3236		if (ret) {
3237			btrfs_warn(fs_info,
3238				   "failed to clear free space tree: %d", ret);
3239			close_ctree(fs_info);
3240			return ret;
3241		}
3242	}
3243
3244	if (btrfs_test_opt(fs_info, FREE_SPACE_TREE) &&
3245	    !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3246		btrfs_info(fs_info, "creating free space tree");
3247		ret = btrfs_create_free_space_tree(fs_info);
3248		if (ret) {
3249			btrfs_warn(fs_info,
3250				"failed to create free space tree: %d", ret);
3251			close_ctree(fs_info);
3252			return ret;
3253		}
3254	}
3255
3256	down_read(&fs_info->cleanup_work_sem);
3257	if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) ||
3258	    (ret = btrfs_orphan_cleanup(fs_info->tree_root))) {
3259		up_read(&fs_info->cleanup_work_sem);
3260		close_ctree(fs_info);
3261		return ret;
3262	}
3263	up_read(&fs_info->cleanup_work_sem);
3264
3265	ret = btrfs_resume_balance_async(fs_info);
3266	if (ret) {
3267		btrfs_warn(fs_info, "failed to resume balance: %d", ret);
3268		close_ctree(fs_info);
3269		return ret;
3270	}
3271
3272	ret = btrfs_resume_dev_replace_async(fs_info);
3273	if (ret) {
3274		btrfs_warn(fs_info, "failed to resume device replace: %d", ret);
3275		close_ctree(fs_info);
3276		return ret;
3277	}
 
3278
3279	btrfs_qgroup_rescan_resume(fs_info);
3280
3281	if (!fs_info->uuid_root) {
3282		btrfs_info(fs_info, "creating UUID tree");
3283		ret = btrfs_create_uuid_tree(fs_info);
3284		if (ret) {
3285			btrfs_warn(fs_info,
3286				"failed to create the UUID tree: %d", ret);
3287			close_ctree(fs_info);
3288			return ret;
3289		}
3290	} else if (btrfs_test_opt(fs_info, RESCAN_UUID_TREE) ||
3291		   fs_info->generation !=
3292				btrfs_super_uuid_tree_generation(disk_super)) {
3293		btrfs_info(fs_info, "checking UUID tree");
3294		ret = btrfs_check_uuid_tree(fs_info);
3295		if (ret) {
3296			btrfs_warn(fs_info,
3297				"failed to check the UUID tree: %d", ret);
3298			close_ctree(fs_info);
3299			return ret;
3300		}
3301	} else {
3302		set_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags);
3303	}
 
3304	set_bit(BTRFS_FS_OPEN, &fs_info->flags);
3305
3306	/*
3307	 * backuproot only affect mount behavior, and if open_ctree succeeded,
3308	 * no need to keep the flag
3309	 */
3310	btrfs_clear_opt(fs_info->mount_opt, USEBACKUPROOT);
3311
 
 
3312	return 0;
3313
3314fail_qgroup:
3315	btrfs_free_qgroup_config(fs_info);
3316fail_trans_kthread:
3317	kthread_stop(fs_info->transaction_kthread);
3318	btrfs_cleanup_transaction(fs_info);
3319	btrfs_free_fs_roots(fs_info);
3320fail_cleaner:
3321	kthread_stop(fs_info->cleaner_kthread);
3322
3323	/*
3324	 * make sure we're done with the btree inode before we stop our
3325	 * kthreads
3326	 */
3327	filemap_write_and_wait(fs_info->btree_inode->i_mapping);
3328
3329fail_sysfs:
3330	btrfs_sysfs_remove_mounted(fs_info);
3331
3332fail_fsdev_sysfs:
3333	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
3334
3335fail_block_groups:
3336	btrfs_put_block_group_cache(fs_info);
3337
3338fail_tree_roots:
3339	free_root_pointers(fs_info, 1);
 
 
3340	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
3341
3342fail_sb_buffer:
3343	btrfs_stop_all_workers(fs_info);
3344	btrfs_free_block_groups(fs_info);
3345fail_csum:
3346	btrfs_free_csum_hash(fs_info);
3347fail_alloc:
3348fail_iput:
3349	btrfs_mapping_tree_free(&fs_info->mapping_tree);
3350
3351	iput(fs_info->btree_inode);
3352fail_bio_counter:
3353	percpu_counter_destroy(&fs_info->dev_replace.bio_counter);
3354fail_delalloc_bytes:
3355	percpu_counter_destroy(&fs_info->delalloc_bytes);
3356fail_dirty_metadata_bytes:
3357	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
3358fail_dio_bytes:
3359	percpu_counter_destroy(&fs_info->dio_bytes);
3360fail_srcu:
3361	cleanup_srcu_struct(&fs_info->subvol_srcu);
3362fail:
3363	btrfs_free_stripe_hash_table(fs_info);
3364	btrfs_close_devices(fs_info->fs_devices);
3365	return err;
 
 
3366
3367recovery_tree_root:
3368	if (!btrfs_test_opt(fs_info, USEBACKUPROOT))
3369		goto fail_tree_roots;
 
 
 
3370
3371	free_root_pointers(fs_info, 0);
 
3372
3373	/* don't use the log in recovery mode, it won't be valid */
3374	btrfs_set_super_log_root(disk_super, 0);
 
 
 
 
 
 
 
 
 
 
3375
3376	/* we can't trust the free space cache either */
3377	btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
 
3378
3379	ret = next_root_backup(fs_info, fs_info->super_copy,
3380			       &num_backups_tried, &backup_index);
3381	if (ret == -1)
3382		goto fail_block_groups;
3383	goto retry_root_backup;
3384}
3385ALLOW_ERROR_INJECTION(open_ctree, ERRNO);
3386
3387static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
 
3388{
3389	if (uptodate) {
3390		set_buffer_uptodate(bh);
3391	} else {
3392		struct btrfs_device *device = (struct btrfs_device *)
3393			bh->b_private;
 
 
 
 
 
 
 
3394
3395		btrfs_warn_rl_in_rcu(device->fs_info,
3396				"lost page write due to IO error on %s",
3397					  rcu_str_deref(device->name));
3398		/* note, we don't set_buffer_write_io_error because we have
3399		 * our own ways of dealing with the IO errors
 
 
 
 
 
3400		 */
3401		clear_buffer_uptodate(bh);
3402		btrfs_dev_stat_inc_and_print(device, BTRFS_DEV_STAT_WRITE_ERRS);
 
3403	}
3404	unlock_buffer(bh);
3405	put_bh(bh);
3406}
3407
3408int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num,
3409			struct buffer_head **bh_ret)
3410{
3411	struct buffer_head *bh;
3412	struct btrfs_super_block *super;
3413	u64 bytenr;
3414
3415	bytenr = btrfs_sb_offset(copy_num);
3416	if (bytenr + BTRFS_SUPER_INFO_SIZE >= i_size_read(bdev->bd_inode))
3417		return -EINVAL;
3418
3419	bh = __bread(bdev, bytenr / BTRFS_BDEV_BLOCKSIZE, BTRFS_SUPER_INFO_SIZE);
3420	/*
3421	 * If we fail to read from the underlying devices, as of now
3422	 * the best option we have is to mark it EIO.
3423	 */
3424	if (!bh)
3425		return -EIO;
3426
3427	super = (struct btrfs_super_block *)bh->b_data;
3428	if (btrfs_super_bytenr(super) != bytenr ||
3429		    btrfs_super_magic(super) != BTRFS_MAGIC) {
3430		brelse(bh);
3431		return -EINVAL;
3432	}
3433
3434	*bh_ret = bh;
3435	return 0;
3436}
3437
3438
3439struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
3440{
3441	struct buffer_head *bh;
3442	struct buffer_head *latest = NULL;
3443	struct btrfs_super_block *super;
3444	int i;
3445	u64 transid = 0;
3446	int ret = -EINVAL;
3447
3448	/* we would like to check all the supers, but that would make
3449	 * a btrfs mount succeed after a mkfs from a different FS.
3450	 * So, we need to add a special mount option to scan for
3451	 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
3452	 */
3453	for (i = 0; i < 1; i++) {
3454		ret = btrfs_read_dev_one_super(bdev, i, &bh);
3455		if (ret)
3456			continue;
3457
3458		super = (struct btrfs_super_block *)bh->b_data;
3459
3460		if (!latest || btrfs_super_generation(super) > transid) {
3461			brelse(latest);
3462			latest = bh;
 
 
3463			transid = btrfs_super_generation(super);
3464		} else {
3465			brelse(bh);
3466		}
3467	}
3468
3469	if (!latest)
3470		return ERR_PTR(ret);
3471
3472	return latest;
3473}
3474
3475/*
3476 * Write superblock @sb to the @device. Do not wait for completion, all the
3477 * buffer heads we write are pinned.
3478 *
3479 * Write @max_mirrors copies of the superblock, where 0 means default that fit
3480 * the expected device size at commit time. Note that max_mirrors must be
3481 * same for write and wait phases.
3482 *
3483 * Return number of errors when buffer head is not found or submission fails.
3484 */
3485static int write_dev_supers(struct btrfs_device *device,
3486			    struct btrfs_super_block *sb, int max_mirrors)
3487{
3488	struct btrfs_fs_info *fs_info = device->fs_info;
 
3489	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
3490	struct buffer_head *bh;
3491	int i;
3492	int ret;
3493	int errors = 0;
3494	u64 bytenr;
3495	int op_flags;
3496
3497	if (max_mirrors == 0)
3498		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
3499
3500	shash->tfm = fs_info->csum_shash;
3501
3502	for (i = 0; i < max_mirrors; i++) {
3503		bytenr = btrfs_sb_offset(i);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3504		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
3505		    device->commit_total_bytes)
3506			break;
3507
3508		btrfs_set_super_bytenr(sb, bytenr);
3509
3510		crypto_shash_init(shash);
3511		crypto_shash_update(shash, (const char *)sb + BTRFS_CSUM_SIZE,
3512				    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
3513		crypto_shash_final(shash, sb->csum);
3514
3515		/* One reference for us, and we leave it for the caller */
3516		bh = __getblk(device->bdev, bytenr / BTRFS_BDEV_BLOCKSIZE,
3517			      BTRFS_SUPER_INFO_SIZE);
3518		if (!bh) {
3519			btrfs_err(device->fs_info,
3520			    "couldn't get super buffer head for bytenr %llu",
3521			    bytenr);
3522			errors++;
3523			continue;
3524		}
3525
3526		memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
 
3527
3528		/* one reference for submit_bh */
3529		get_bh(bh);
3530
3531		set_buffer_uptodate(bh);
3532		lock_buffer(bh);
3533		bh->b_end_io = btrfs_end_buffer_write_sync;
3534		bh->b_private = device;
 
 
 
 
 
 
 
 
 
3535
3536		/*
3537		 * we fua the first super.  The others we allow
3538		 * to go down lazy.
 
3539		 */
3540		op_flags = REQ_SYNC | REQ_META | REQ_PRIO;
3541		if (i == 0 && !btrfs_test_opt(device->fs_info, NOBARRIER))
3542			op_flags |= REQ_FUA;
3543		ret = btrfsic_submit_bh(REQ_OP_WRITE, op_flags, bh);
3544		if (ret)
 
 
 
3545			errors++;
3546	}
3547	return errors < i ? 0 : -1;
3548}
3549
3550/*
3551 * Wait for write completion of superblocks done by write_dev_supers,
3552 * @max_mirrors same for write and wait phases.
3553 *
3554 * Return number of errors when buffer head is not found or not marked up to
3555 * date.
3556 */
3557static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
3558{
3559	struct buffer_head *bh;
3560	int i;
3561	int errors = 0;
3562	bool primary_failed = false;
 
3563	u64 bytenr;
3564
3565	if (max_mirrors == 0)
3566		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
3567
3568	for (i = 0; i < max_mirrors; i++) {
3569		bytenr = btrfs_sb_offset(i);
 
 
 
 
 
 
 
 
 
 
3570		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
3571		    device->commit_total_bytes)
3572			break;
3573
3574		bh = __find_get_block(device->bdev,
3575				      bytenr / BTRFS_BDEV_BLOCKSIZE,
3576				      BTRFS_SUPER_INFO_SIZE);
3577		if (!bh) {
3578			errors++;
3579			if (i == 0)
3580				primary_failed = true;
3581			continue;
3582		}
3583		wait_on_buffer(bh);
3584		if (!buffer_uptodate(bh)) {
 
3585			errors++;
3586			if (i == 0)
3587				primary_failed = true;
3588		}
3589
3590		/* drop our reference */
3591		brelse(bh);
3592
3593		/* drop the reference from the writing run */
3594		brelse(bh);
3595	}
3596
3597	/* log error, force error return */
3598	if (primary_failed) {
3599		btrfs_err(device->fs_info, "error writing primary super block to device %llu",
3600			  device->devid);
3601		return -1;
3602	}
3603
3604	return errors < i ? 0 : -1;
3605}
3606
3607/*
3608 * endio for the write_dev_flush, this will wake anyone waiting
3609 * for the barrier when it is done
3610 */
3611static void btrfs_end_empty_barrier(struct bio *bio)
3612{
 
3613	complete(bio->bi_private);
3614}
3615
3616/*
3617 * Submit a flush request to the device if it supports it. Error handling is
3618 * done in the waiting counterpart.
3619 */
3620static void write_dev_flush(struct btrfs_device *device)
3621{
3622	struct request_queue *q = bdev_get_queue(device->bdev);
3623	struct bio *bio = device->flush_bio;
3624
3625	if (!test_bit(QUEUE_FLAG_WC, &q->queue_flags))
 
 
 
 
 
 
 
 
 
 
 
3626		return;
 
3627
3628	bio_reset(bio);
 
3629	bio->bi_end_io = btrfs_end_empty_barrier;
3630	bio_set_dev(bio, device->bdev);
3631	bio->bi_opf = REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH;
3632	init_completion(&device->flush_wait);
3633	bio->bi_private = &device->flush_wait;
3634
3635	btrfsic_submit_bio(bio);
 
3636	set_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
3637}
3638
3639/*
3640 * If the flush bio has been submitted by write_dev_flush, wait for it.
3641 */
3642static blk_status_t wait_dev_flush(struct btrfs_device *device)
3643{
3644	struct bio *bio = device->flush_bio;
3645
3646	if (!test_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state))
3647		return BLK_STS_OK;
3648
3649	clear_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
3650	wait_for_completion_io(&device->flush_wait);
3651
3652	return bio->bi_status;
3653}
3654
3655static int check_barrier_error(struct btrfs_fs_info *fs_info)
3656{
3657	if (!btrfs_check_rw_degradable(fs_info, NULL))
3658		return -EIO;
3659	return 0;
3660}
3661
3662/*
3663 * send an empty flush down to each device in parallel,
3664 * then wait for them
3665 */
3666static int barrier_all_devices(struct btrfs_fs_info *info)
3667{
3668	struct list_head *head;
3669	struct btrfs_device *dev;
3670	int errors_wait = 0;
3671	blk_status_t ret;
3672
3673	lockdep_assert_held(&info->fs_devices->device_list_mutex);
3674	/* send down all the barriers */
3675	head = &info->fs_devices->devices;
3676	list_for_each_entry(dev, head, dev_list) {
3677		if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
3678			continue;
3679		if (!dev->bdev)
3680			continue;
3681		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3682		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
3683			continue;
3684
3685		write_dev_flush(dev);
3686		dev->last_flush_error = BLK_STS_OK;
3687	}
3688
3689	/* wait for all the barriers */
3690	list_for_each_entry(dev, head, dev_list) {
3691		if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
3692			continue;
3693		if (!dev->bdev) {
3694			errors_wait++;
3695			continue;
3696		}
3697		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3698		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
3699			continue;
3700
3701		ret = wait_dev_flush(dev);
3702		if (ret) {
3703			dev->last_flush_error = ret;
3704			btrfs_dev_stat_inc_and_print(dev,
3705					BTRFS_DEV_STAT_FLUSH_ERRS);
3706			errors_wait++;
3707		}
3708	}
3709
3710	if (errors_wait) {
3711		/*
3712		 * At some point we need the status of all disks
3713		 * to arrive at the volume status. So error checking
3714		 * is being pushed to a separate loop.
3715		 */
3716		return check_barrier_error(info);
3717	}
3718	return 0;
3719}
3720
3721int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags)
3722{
3723	int raid_type;
3724	int min_tolerated = INT_MAX;
3725
3726	if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 ||
3727	    (flags & BTRFS_AVAIL_ALLOC_BIT_SINGLE))
3728		min_tolerated = min_t(int, min_tolerated,
3729				    btrfs_raid_array[BTRFS_RAID_SINGLE].
3730				    tolerated_failures);
3731
3732	for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
3733		if (raid_type == BTRFS_RAID_SINGLE)
3734			continue;
3735		if (!(flags & btrfs_raid_array[raid_type].bg_flag))
3736			continue;
3737		min_tolerated = min_t(int, min_tolerated,
3738				    btrfs_raid_array[raid_type].
3739				    tolerated_failures);
3740	}
3741
3742	if (min_tolerated == INT_MAX) {
3743		pr_warn("BTRFS: unknown raid flag: %llu", flags);
3744		min_tolerated = 0;
3745	}
3746
3747	return min_tolerated;
3748}
3749
3750int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors)
3751{
3752	struct list_head *head;
3753	struct btrfs_device *dev;
3754	struct btrfs_super_block *sb;
3755	struct btrfs_dev_item *dev_item;
3756	int ret;
3757	int do_barriers;
3758	int max_errors;
3759	int total_errors = 0;
3760	u64 flags;
3761
3762	do_barriers = !btrfs_test_opt(fs_info, NOBARRIER);
3763
3764	/*
3765	 * max_mirrors == 0 indicates we're from commit_transaction,
3766	 * not from fsync where the tree roots in fs_info have not
3767	 * been consistent on disk.
3768	 */
3769	if (max_mirrors == 0)
3770		backup_super_roots(fs_info);
3771
3772	sb = fs_info->super_for_commit;
3773	dev_item = &sb->dev_item;
3774
3775	mutex_lock(&fs_info->fs_devices->device_list_mutex);
3776	head = &fs_info->fs_devices->devices;
3777	max_errors = btrfs_super_num_devices(fs_info->super_copy) - 1;
3778
3779	if (do_barriers) {
3780		ret = barrier_all_devices(fs_info);
3781		if (ret) {
3782			mutex_unlock(
3783				&fs_info->fs_devices->device_list_mutex);
3784			btrfs_handle_fs_error(fs_info, ret,
3785					      "errors while submitting device barriers.");
3786			return ret;
3787		}
3788	}
3789
3790	list_for_each_entry(dev, head, dev_list) {
3791		if (!dev->bdev) {
3792			total_errors++;
3793			continue;
3794		}
3795		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3796		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
3797			continue;
3798
3799		btrfs_set_stack_device_generation(dev_item, 0);
3800		btrfs_set_stack_device_type(dev_item, dev->type);
3801		btrfs_set_stack_device_id(dev_item, dev->devid);
3802		btrfs_set_stack_device_total_bytes(dev_item,
3803						   dev->commit_total_bytes);
3804		btrfs_set_stack_device_bytes_used(dev_item,
3805						  dev->commit_bytes_used);
3806		btrfs_set_stack_device_io_align(dev_item, dev->io_align);
3807		btrfs_set_stack_device_io_width(dev_item, dev->io_width);
3808		btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
3809		memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
3810		memcpy(dev_item->fsid, dev->fs_devices->metadata_uuid,
3811		       BTRFS_FSID_SIZE);
3812
3813		flags = btrfs_super_flags(sb);
3814		btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
3815
3816		ret = btrfs_validate_write_super(fs_info, sb);
3817		if (ret < 0) {
3818			mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3819			btrfs_handle_fs_error(fs_info, -EUCLEAN,
3820				"unexpected superblock corruption detected");
3821			return -EUCLEAN;
3822		}
3823
3824		ret = write_dev_supers(dev, sb, max_mirrors);
3825		if (ret)
3826			total_errors++;
3827	}
3828	if (total_errors > max_errors) {
3829		btrfs_err(fs_info, "%d errors while writing supers",
3830			  total_errors);
3831		mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3832
3833		/* FUA is masked off if unsupported and can't be the reason */
3834		btrfs_handle_fs_error(fs_info, -EIO,
3835				      "%d errors while writing supers",
3836				      total_errors);
3837		return -EIO;
3838	}
3839
3840	total_errors = 0;
3841	list_for_each_entry(dev, head, dev_list) {
3842		if (!dev->bdev)
3843			continue;
3844		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3845		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
3846			continue;
3847
3848		ret = wait_dev_supers(dev, max_mirrors);
3849		if (ret)
3850			total_errors++;
3851	}
3852	mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3853	if (total_errors > max_errors) {
3854		btrfs_handle_fs_error(fs_info, -EIO,
3855				      "%d errors while writing supers",
3856				      total_errors);
3857		return -EIO;
3858	}
3859	return 0;
3860}
3861
3862/* Drop a fs root from the radix tree and free it. */
3863void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
3864				  struct btrfs_root *root)
3865{
 
 
3866	spin_lock(&fs_info->fs_roots_radix_lock);
3867	radix_tree_delete(&fs_info->fs_roots_radix,
3868			  (unsigned long)root->root_key.objectid);
 
 
3869	spin_unlock(&fs_info->fs_roots_radix_lock);
3870
3871	if (btrfs_root_refs(&root->root_item) == 0)
3872		synchronize_srcu(&fs_info->subvol_srcu);
3873
3874	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
3875		btrfs_free_log(NULL, root);
3876		if (root->reloc_root) {
3877			free_extent_buffer(root->reloc_root->node);
3878			free_extent_buffer(root->reloc_root->commit_root);
3879			btrfs_put_fs_root(root->reloc_root);
3880			root->reloc_root = NULL;
3881		}
3882	}
3883
3884	if (root->free_ino_pinned)
3885		__btrfs_remove_free_space_cache(root->free_ino_pinned);
3886	if (root->free_ino_ctl)
3887		__btrfs_remove_free_space_cache(root->free_ino_ctl);
3888	btrfs_free_fs_root(root);
3889}
3890
3891void btrfs_free_fs_root(struct btrfs_root *root)
3892{
3893	iput(root->ino_cache_inode);
3894	WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
3895	if (root->anon_dev)
3896		free_anon_bdev(root->anon_dev);
3897	if (root->subv_writers)
3898		btrfs_free_subvolume_writers(root->subv_writers);
3899	free_extent_buffer(root->node);
3900	free_extent_buffer(root->commit_root);
3901	kfree(root->free_ino_ctl);
3902	kfree(root->free_ino_pinned);
3903	btrfs_put_fs_root(root);
3904}
3905
3906int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
3907{
3908	u64 root_objectid = 0;
3909	struct btrfs_root *gang[8];
3910	int i = 0;
3911	int err = 0;
3912	unsigned int ret = 0;
3913	int index;
3914
3915	while (1) {
3916		index = srcu_read_lock(&fs_info->subvol_srcu);
3917		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
3918					     (void **)gang, root_objectid,
3919					     ARRAY_SIZE(gang));
3920		if (!ret) {
3921			srcu_read_unlock(&fs_info->subvol_srcu, index);
3922			break;
3923		}
3924		root_objectid = gang[ret - 1]->root_key.objectid + 1;
3925
3926		for (i = 0; i < ret; i++) {
3927			/* Avoid to grab roots in dead_roots */
3928			if (btrfs_root_refs(&gang[i]->root_item) == 0) {
3929				gang[i] = NULL;
3930				continue;
3931			}
3932			/* grab all the search result for later use */
3933			gang[i] = btrfs_grab_fs_root(gang[i]);
3934		}
3935		srcu_read_unlock(&fs_info->subvol_srcu, index);
3936
3937		for (i = 0; i < ret; i++) {
3938			if (!gang[i])
3939				continue;
3940			root_objectid = gang[i]->root_key.objectid;
3941			err = btrfs_orphan_cleanup(gang[i]);
3942			if (err)
3943				break;
3944			btrfs_put_fs_root(gang[i]);
3945		}
3946		root_objectid++;
3947	}
3948
3949	/* release the uncleaned roots due to error */
3950	for (; i < ret; i++) {
3951		if (gang[i])
3952			btrfs_put_fs_root(gang[i]);
3953	}
3954	return err;
3955}
3956
3957int btrfs_commit_super(struct btrfs_fs_info *fs_info)
3958{
3959	struct btrfs_root *root = fs_info->tree_root;
3960	struct btrfs_trans_handle *trans;
3961
3962	mutex_lock(&fs_info->cleaner_mutex);
3963	btrfs_run_delayed_iputs(fs_info);
3964	mutex_unlock(&fs_info->cleaner_mutex);
3965	wake_up_process(fs_info->cleaner_kthread);
3966
3967	/* wait until ongoing cleanup work done */
3968	down_write(&fs_info->cleanup_work_sem);
3969	up_write(&fs_info->cleanup_work_sem);
3970
3971	trans = btrfs_join_transaction(root);
3972	if (IS_ERR(trans))
3973		return PTR_ERR(trans);
3974	return btrfs_commit_transaction(trans);
3975}
3976
3977void close_ctree(struct btrfs_fs_info *fs_info)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3978{
3979	int ret;
3980
3981	set_bit(BTRFS_FS_CLOSING_START, &fs_info->flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3982	/*
3983	 * We don't want the cleaner to start new transactions, add more delayed
3984	 * iputs, etc. while we're closing. We can't use kthread_stop() yet
3985	 * because that frees the task_struct, and the transaction kthread might
3986	 * still try to wake up the cleaner.
3987	 */
3988	kthread_park(fs_info->cleaner_kthread);
3989
3990	/* wait for the qgroup rescan worker to stop */
3991	btrfs_qgroup_wait_for_completion(fs_info, false);
3992
3993	/* wait for the uuid_scan task to finish */
3994	down(&fs_info->uuid_tree_rescan_sem);
3995	/* avoid complains from lockdep et al., set sem back to initial state */
3996	up(&fs_info->uuid_tree_rescan_sem);
3997
3998	/* pause restriper - we want to resume on mount */
3999	btrfs_pause_balance(fs_info);
4000
4001	btrfs_dev_replace_suspend_for_unmount(fs_info);
4002
4003	btrfs_scrub_cancel(fs_info);
4004
4005	/* wait for any defraggers to finish */
4006	wait_event(fs_info->transaction_wait,
4007		   (atomic_read(&fs_info->defrag_running) == 0));
4008
4009	/* clear out the rbtree of defraggable inodes */
4010	btrfs_cleanup_defrag_inodes(fs_info);
4011
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4012	cancel_work_sync(&fs_info->async_reclaim_work);
 
 
 
 
 
4013
4014	if (!sb_rdonly(fs_info->sb)) {
4015		/*
4016		 * The cleaner kthread is stopped, so do one final pass over
4017		 * unused block groups.
4018		 */
4019		btrfs_delete_unused_bgs(fs_info);
4020
 
 
 
 
 
 
 
 
 
 
 
 
 
4021		ret = btrfs_commit_super(fs_info);
4022		if (ret)
4023			btrfs_err(fs_info, "commit super ret %d", ret);
4024	}
4025
4026	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state) ||
4027	    test_bit(BTRFS_FS_STATE_TRANS_ABORTED, &fs_info->fs_state))
4028		btrfs_error_commit_super(fs_info);
4029
4030	kthread_stop(fs_info->transaction_kthread);
4031	kthread_stop(fs_info->cleaner_kthread);
4032
4033	ASSERT(list_empty(&fs_info->delayed_iputs));
4034	set_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags);
4035
 
 
 
 
 
4036	btrfs_free_qgroup_config(fs_info);
4037	ASSERT(list_empty(&fs_info->delalloc_roots));
4038
4039	if (percpu_counter_sum(&fs_info->delalloc_bytes)) {
4040		btrfs_info(fs_info, "at unmount delalloc count %lld",
4041		       percpu_counter_sum(&fs_info->delalloc_bytes));
4042	}
4043
4044	if (percpu_counter_sum(&fs_info->dio_bytes))
4045		btrfs_info(fs_info, "at unmount dio bytes count %lld",
4046			   percpu_counter_sum(&fs_info->dio_bytes));
4047
4048	btrfs_sysfs_remove_mounted(fs_info);
4049	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
4050
4051	btrfs_free_fs_roots(fs_info);
4052
4053	btrfs_put_block_group_cache(fs_info);
4054
4055	/*
4056	 * we must make sure there is not any read request to
4057	 * submit after we stopping all workers.
4058	 */
4059	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
4060	btrfs_stop_all_workers(fs_info);
4061
4062	btrfs_free_block_groups(fs_info);
 
4063
4064	clear_bit(BTRFS_FS_OPEN, &fs_info->flags);
4065	free_root_pointers(fs_info, 1);
 
 
 
 
 
 
 
 
 
 
4066
4067	iput(fs_info->btree_inode);
4068
4069#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4070	if (btrfs_test_opt(fs_info, CHECK_INTEGRITY))
4071		btrfsic_unmount(fs_info->fs_devices);
4072#endif
4073
4074	btrfs_mapping_tree_free(&fs_info->mapping_tree);
4075	btrfs_close_devices(fs_info->fs_devices);
4076
4077	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
4078	percpu_counter_destroy(&fs_info->delalloc_bytes);
4079	percpu_counter_destroy(&fs_info->dio_bytes);
4080	percpu_counter_destroy(&fs_info->dev_replace.bio_counter);
4081	cleanup_srcu_struct(&fs_info->subvol_srcu);
4082
4083	btrfs_free_csum_hash(fs_info);
4084	btrfs_free_stripe_hash_table(fs_info);
4085	btrfs_free_ref_cache(fs_info);
4086}
4087
4088int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
4089			  int atomic)
4090{
4091	int ret;
4092	struct inode *btree_inode = buf->pages[0]->mapping->host;
4093
4094	ret = extent_buffer_uptodate(buf);
4095	if (!ret)
4096		return ret;
4097
4098	ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
4099				    parent_transid, atomic);
4100	if (ret == -EAGAIN)
4101		return ret;
4102	return !ret;
4103}
4104
4105void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
4106{
4107	struct btrfs_fs_info *fs_info;
4108	struct btrfs_root *root;
4109	u64 transid = btrfs_header_generation(buf);
4110	int was_dirty;
4111
4112#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4113	/*
4114	 * This is a fast path so only do this check if we have sanity tests
4115	 * enabled.  Normal people shouldn't be using unmapped buffers as dirty
4116	 * outside of the sanity tests.
4117	 */
4118	if (unlikely(test_bit(EXTENT_BUFFER_UNMAPPED, &buf->bflags)))
4119		return;
4120#endif
4121	root = BTRFS_I(buf->pages[0]->mapping->host)->root;
4122	fs_info = root->fs_info;
4123	btrfs_assert_tree_locked(buf);
4124	if (transid != fs_info->generation)
4125		WARN(1, KERN_CRIT "btrfs transid mismatch buffer %llu, found %llu running %llu\n",
4126			buf->start, transid, fs_info->generation);
4127	was_dirty = set_extent_buffer_dirty(buf);
4128	if (!was_dirty)
4129		percpu_counter_add_batch(&fs_info->dirty_metadata_bytes,
4130					 buf->len,
4131					 fs_info->dirty_metadata_batch);
4132#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4133	/*
4134	 * Since btrfs_mark_buffer_dirty() can be called with item pointer set
4135	 * but item data not updated.
4136	 * So here we should only check item pointers, not item data.
4137	 */
4138	if (btrfs_header_level(buf) == 0 &&
4139	    btrfs_check_leaf_relaxed(buf)) {
4140		btrfs_print_leaf(buf);
4141		ASSERT(0);
4142	}
4143#endif
4144}
4145
4146static void __btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info,
4147					int flush_delayed)
4148{
4149	/*
4150	 * looks as though older kernels can get into trouble with
4151	 * this code, they end up stuck in balance_dirty_pages forever
4152	 */
4153	int ret;
4154
4155	if (current->flags & PF_MEMALLOC)
4156		return;
4157
4158	if (flush_delayed)
4159		btrfs_balance_delayed_items(fs_info);
4160
4161	ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
4162				     BTRFS_DIRTY_METADATA_THRESH,
4163				     fs_info->dirty_metadata_batch);
4164	if (ret > 0) {
4165		balance_dirty_pages_ratelimited(fs_info->btree_inode->i_mapping);
4166	}
4167}
4168
4169void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info)
4170{
4171	__btrfs_btree_balance_dirty(fs_info, 1);
4172}
4173
4174void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info)
4175{
4176	__btrfs_btree_balance_dirty(fs_info, 0);
4177}
4178
4179int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level,
4180		      struct btrfs_key *first_key)
4181{
4182	return btree_read_extent_buffer_pages(buf, parent_transid,
4183					      level, first_key);
4184}
4185
4186static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info)
4187{
4188	/* cleanup FS via transaction */
4189	btrfs_cleanup_transaction(fs_info);
4190
4191	mutex_lock(&fs_info->cleaner_mutex);
4192	btrfs_run_delayed_iputs(fs_info);
4193	mutex_unlock(&fs_info->cleaner_mutex);
4194
4195	down_write(&fs_info->cleanup_work_sem);
4196	up_write(&fs_info->cleanup_work_sem);
4197}
4198
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4199static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
4200{
4201	struct btrfs_ordered_extent *ordered;
4202
4203	spin_lock(&root->ordered_extent_lock);
4204	/*
4205	 * This will just short circuit the ordered completion stuff which will
4206	 * make sure the ordered extent gets properly cleaned up.
4207	 */
4208	list_for_each_entry(ordered, &root->ordered_extents,
4209			    root_extent_list)
4210		set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
4211	spin_unlock(&root->ordered_extent_lock);
4212}
4213
4214static void btrfs_destroy_all_ordered_extents(struct btrfs_fs_info *fs_info)
4215{
4216	struct btrfs_root *root;
4217	struct list_head splice;
4218
4219	INIT_LIST_HEAD(&splice);
4220
4221	spin_lock(&fs_info->ordered_root_lock);
4222	list_splice_init(&fs_info->ordered_roots, &splice);
4223	while (!list_empty(&splice)) {
4224		root = list_first_entry(&splice, struct btrfs_root,
4225					ordered_root);
4226		list_move_tail(&root->ordered_root,
4227			       &fs_info->ordered_roots);
4228
4229		spin_unlock(&fs_info->ordered_root_lock);
4230		btrfs_destroy_ordered_extents(root);
4231
4232		cond_resched();
4233		spin_lock(&fs_info->ordered_root_lock);
4234	}
4235	spin_unlock(&fs_info->ordered_root_lock);
4236
4237	/*
4238	 * We need this here because if we've been flipped read-only we won't
4239	 * get sync() from the umount, so we need to make sure any ordered
4240	 * extents that haven't had their dirty pages IO start writeout yet
4241	 * actually get run and error out properly.
4242	 */
4243	btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
4244}
4245
4246static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
4247				      struct btrfs_fs_info *fs_info)
4248{
4249	struct rb_node *node;
4250	struct btrfs_delayed_ref_root *delayed_refs;
4251	struct btrfs_delayed_ref_node *ref;
4252	int ret = 0;
4253
4254	delayed_refs = &trans->delayed_refs;
4255
4256	spin_lock(&delayed_refs->lock);
4257	if (atomic_read(&delayed_refs->num_entries) == 0) {
4258		spin_unlock(&delayed_refs->lock);
4259		btrfs_info(fs_info, "delayed_refs has NO entry");
4260		return ret;
4261	}
4262
4263	while ((node = rb_first_cached(&delayed_refs->href_root)) != NULL) {
4264		struct btrfs_delayed_ref_head *head;
4265		struct rb_node *n;
4266		bool pin_bytes = false;
4267
4268		head = rb_entry(node, struct btrfs_delayed_ref_head,
4269				href_node);
4270		if (btrfs_delayed_ref_lock(delayed_refs, head))
4271			continue;
4272
4273		spin_lock(&head->lock);
4274		while ((n = rb_first_cached(&head->ref_tree)) != NULL) {
4275			ref = rb_entry(n, struct btrfs_delayed_ref_node,
4276				       ref_node);
4277			ref->in_tree = 0;
4278			rb_erase_cached(&ref->ref_node, &head->ref_tree);
4279			RB_CLEAR_NODE(&ref->ref_node);
4280			if (!list_empty(&ref->add_list))
4281				list_del(&ref->add_list);
4282			atomic_dec(&delayed_refs->num_entries);
4283			btrfs_put_delayed_ref(ref);
4284		}
4285		if (head->must_insert_reserved)
4286			pin_bytes = true;
4287		btrfs_free_delayed_extent_op(head->extent_op);
4288		btrfs_delete_ref_head(delayed_refs, head);
4289		spin_unlock(&head->lock);
4290		spin_unlock(&delayed_refs->lock);
4291		mutex_unlock(&head->mutex);
4292
4293		if (pin_bytes)
4294			btrfs_pin_extent(fs_info, head->bytenr,
4295					 head->num_bytes, 1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4296		btrfs_cleanup_ref_head_accounting(fs_info, delayed_refs, head);
4297		btrfs_put_delayed_ref_head(head);
4298		cond_resched();
4299		spin_lock(&delayed_refs->lock);
4300	}
 
4301
4302	spin_unlock(&delayed_refs->lock);
4303
4304	return ret;
4305}
4306
4307static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
4308{
4309	struct btrfs_inode *btrfs_inode;
4310	struct list_head splice;
4311
4312	INIT_LIST_HEAD(&splice);
4313
4314	spin_lock(&root->delalloc_lock);
4315	list_splice_init(&root->delalloc_inodes, &splice);
4316
4317	while (!list_empty(&splice)) {
4318		struct inode *inode = NULL;
4319		btrfs_inode = list_first_entry(&splice, struct btrfs_inode,
4320					       delalloc_inodes);
4321		__btrfs_del_delalloc_inode(root, btrfs_inode);
4322		spin_unlock(&root->delalloc_lock);
4323
4324		/*
4325		 * Make sure we get a live inode and that it'll not disappear
4326		 * meanwhile.
4327		 */
4328		inode = igrab(&btrfs_inode->vfs_inode);
4329		if (inode) {
4330			invalidate_inode_pages2(inode->i_mapping);
4331			iput(inode);
4332		}
4333		spin_lock(&root->delalloc_lock);
4334	}
4335	spin_unlock(&root->delalloc_lock);
4336}
4337
4338static void btrfs_destroy_all_delalloc_inodes(struct btrfs_fs_info *fs_info)
4339{
4340	struct btrfs_root *root;
4341	struct list_head splice;
4342
4343	INIT_LIST_HEAD(&splice);
4344
4345	spin_lock(&fs_info->delalloc_root_lock);
4346	list_splice_init(&fs_info->delalloc_roots, &splice);
4347	while (!list_empty(&splice)) {
4348		root = list_first_entry(&splice, struct btrfs_root,
4349					 delalloc_root);
4350		root = btrfs_grab_fs_root(root);
4351		BUG_ON(!root);
4352		spin_unlock(&fs_info->delalloc_root_lock);
4353
4354		btrfs_destroy_delalloc_inodes(root);
4355		btrfs_put_fs_root(root);
4356
4357		spin_lock(&fs_info->delalloc_root_lock);
4358	}
4359	spin_unlock(&fs_info->delalloc_root_lock);
4360}
4361
4362static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
4363					struct extent_io_tree *dirty_pages,
4364					int mark)
4365{
4366	int ret;
4367	struct extent_buffer *eb;
4368	u64 start = 0;
4369	u64 end;
4370
4371	while (1) {
4372		ret = find_first_extent_bit(dirty_pages, start, &start, &end,
4373					    mark, NULL);
4374		if (ret)
4375			break;
4376
4377		clear_extent_bits(dirty_pages, start, end, mark);
4378		while (start <= end) {
4379			eb = find_extent_buffer(fs_info, start);
4380			start += fs_info->nodesize;
4381			if (!eb)
4382				continue;
4383			wait_on_extent_buffer_writeback(eb);
4384
4385			if (test_and_clear_bit(EXTENT_BUFFER_DIRTY,
4386					       &eb->bflags))
4387				clear_extent_buffer_dirty(eb);
4388			free_extent_buffer_stale(eb);
4389		}
4390	}
4391
4392	return ret;
4393}
4394
4395static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
4396				       struct extent_io_tree *pinned_extents)
4397{
4398	struct extent_io_tree *unpin;
4399	u64 start;
4400	u64 end;
4401	int ret;
4402	bool loop = true;
4403
4404	unpin = pinned_extents;
4405again:
4406	while (1) {
4407		struct extent_state *cached_state = NULL;
4408
4409		/*
4410		 * The btrfs_finish_extent_commit() may get the same range as
4411		 * ours between find_first_extent_bit and clear_extent_dirty.
4412		 * Hence, hold the unused_bg_unpin_mutex to avoid double unpin
4413		 * the same extent range.
4414		 */
4415		mutex_lock(&fs_info->unused_bg_unpin_mutex);
4416		ret = find_first_extent_bit(unpin, 0, &start, &end,
4417					    EXTENT_DIRTY, &cached_state);
4418		if (ret) {
4419			mutex_unlock(&fs_info->unused_bg_unpin_mutex);
4420			break;
4421		}
4422
4423		clear_extent_dirty(unpin, start, end, &cached_state);
4424		free_extent_state(cached_state);
4425		btrfs_error_unpin_extent_range(fs_info, start, end);
4426		mutex_unlock(&fs_info->unused_bg_unpin_mutex);
4427		cond_resched();
4428	}
4429
4430	if (loop) {
4431		if (unpin == &fs_info->freed_extents[0])
4432			unpin = &fs_info->freed_extents[1];
4433		else
4434			unpin = &fs_info->freed_extents[0];
4435		loop = false;
4436		goto again;
4437	}
4438
4439	return 0;
4440}
4441
4442static void btrfs_cleanup_bg_io(struct btrfs_block_group_cache *cache)
4443{
4444	struct inode *inode;
4445
4446	inode = cache->io_ctl.inode;
4447	if (inode) {
4448		invalidate_inode_pages2(inode->i_mapping);
4449		BTRFS_I(inode)->generation = 0;
4450		cache->io_ctl.inode = NULL;
4451		iput(inode);
4452	}
 
4453	btrfs_put_block_group(cache);
4454}
4455
4456void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *cur_trans,
4457			     struct btrfs_fs_info *fs_info)
4458{
4459	struct btrfs_block_group_cache *cache;
4460
4461	spin_lock(&cur_trans->dirty_bgs_lock);
4462	while (!list_empty(&cur_trans->dirty_bgs)) {
4463		cache = list_first_entry(&cur_trans->dirty_bgs,
4464					 struct btrfs_block_group_cache,
4465					 dirty_list);
4466
4467		if (!list_empty(&cache->io_list)) {
4468			spin_unlock(&cur_trans->dirty_bgs_lock);
4469			list_del_init(&cache->io_list);
4470			btrfs_cleanup_bg_io(cache);
4471			spin_lock(&cur_trans->dirty_bgs_lock);
4472		}
4473
4474		list_del_init(&cache->dirty_list);
4475		spin_lock(&cache->lock);
4476		cache->disk_cache_state = BTRFS_DC_ERROR;
4477		spin_unlock(&cache->lock);
4478
4479		spin_unlock(&cur_trans->dirty_bgs_lock);
4480		btrfs_put_block_group(cache);
4481		btrfs_delayed_refs_rsv_release(fs_info, 1);
4482		spin_lock(&cur_trans->dirty_bgs_lock);
4483	}
4484	spin_unlock(&cur_trans->dirty_bgs_lock);
4485
4486	/*
4487	 * Refer to the definition of io_bgs member for details why it's safe
4488	 * to use it without any locking
4489	 */
4490	while (!list_empty(&cur_trans->io_bgs)) {
4491		cache = list_first_entry(&cur_trans->io_bgs,
4492					 struct btrfs_block_group_cache,
4493					 io_list);
4494
4495		list_del_init(&cache->io_list);
4496		spin_lock(&cache->lock);
4497		cache->disk_cache_state = BTRFS_DC_ERROR;
4498		spin_unlock(&cache->lock);
4499		btrfs_cleanup_bg_io(cache);
4500	}
4501}
4502
4503void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
4504				   struct btrfs_fs_info *fs_info)
4505{
4506	struct btrfs_device *dev, *tmp;
4507
4508	btrfs_cleanup_dirty_bgs(cur_trans, fs_info);
4509	ASSERT(list_empty(&cur_trans->dirty_bgs));
4510	ASSERT(list_empty(&cur_trans->io_bgs));
4511
4512	list_for_each_entry_safe(dev, tmp, &cur_trans->dev_update_list,
4513				 post_commit_list) {
4514		list_del_init(&dev->post_commit_list);
4515	}
4516
4517	btrfs_destroy_delayed_refs(cur_trans, fs_info);
4518
4519	cur_trans->state = TRANS_STATE_COMMIT_START;
4520	wake_up(&fs_info->transaction_blocked_wait);
4521
4522	cur_trans->state = TRANS_STATE_UNBLOCKED;
4523	wake_up(&fs_info->transaction_wait);
4524
4525	btrfs_destroy_delayed_inodes(fs_info);
4526	btrfs_assert_delayed_root_empty(fs_info);
4527
4528	btrfs_destroy_marked_extents(fs_info, &cur_trans->dirty_pages,
4529				     EXTENT_DIRTY);
4530	btrfs_destroy_pinned_extent(fs_info,
4531				    fs_info->pinned_extents);
 
4532
4533	cur_trans->state =TRANS_STATE_COMPLETED;
4534	wake_up(&cur_trans->commit_wait);
4535}
4536
4537static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info)
4538{
4539	struct btrfs_transaction *t;
4540
4541	mutex_lock(&fs_info->transaction_kthread_mutex);
4542
4543	spin_lock(&fs_info->trans_lock);
4544	while (!list_empty(&fs_info->trans_list)) {
4545		t = list_first_entry(&fs_info->trans_list,
4546				     struct btrfs_transaction, list);
4547		if (t->state >= TRANS_STATE_COMMIT_START) {
4548			refcount_inc(&t->use_count);
4549			spin_unlock(&fs_info->trans_lock);
4550			btrfs_wait_for_commit(fs_info, t->transid);
4551			btrfs_put_transaction(t);
4552			spin_lock(&fs_info->trans_lock);
4553			continue;
4554		}
4555		if (t == fs_info->running_transaction) {
4556			t->state = TRANS_STATE_COMMIT_DOING;
4557			spin_unlock(&fs_info->trans_lock);
4558			/*
4559			 * We wait for 0 num_writers since we don't hold a trans
4560			 * handle open currently for this transaction.
4561			 */
4562			wait_event(t->writer_wait,
4563				   atomic_read(&t->num_writers) == 0);
4564		} else {
4565			spin_unlock(&fs_info->trans_lock);
4566		}
4567		btrfs_cleanup_one_transaction(t, fs_info);
4568
4569		spin_lock(&fs_info->trans_lock);
4570		if (t == fs_info->running_transaction)
4571			fs_info->running_transaction = NULL;
4572		list_del_init(&t->list);
4573		spin_unlock(&fs_info->trans_lock);
4574
4575		btrfs_put_transaction(t);
4576		trace_btrfs_transaction_commit(fs_info->tree_root);
4577		spin_lock(&fs_info->trans_lock);
4578	}
4579	spin_unlock(&fs_info->trans_lock);
4580	btrfs_destroy_all_ordered_extents(fs_info);
4581	btrfs_destroy_delayed_inodes(fs_info);
4582	btrfs_assert_delayed_root_empty(fs_info);
4583	btrfs_destroy_pinned_extent(fs_info, fs_info->pinned_extents);
4584	btrfs_destroy_all_delalloc_inodes(fs_info);
 
4585	mutex_unlock(&fs_info->transaction_kthread_mutex);
4586
4587	return 0;
4588}
4589
4590static const struct extent_io_ops btree_extent_io_ops = {
4591	/* mandatory callbacks */
4592	.submit_bio_hook = btree_submit_bio_hook,
4593	.readpage_end_io_hook = btree_readpage_end_io_hook,
4594};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
v6.2
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) 2007 Oracle.  All rights reserved.
   4 */
   5
   6#include <linux/fs.h>
   7#include <linux/blkdev.h>
   8#include <linux/radix-tree.h>
   9#include <linux/writeback.h>
 
  10#include <linux/workqueue.h>
  11#include <linux/kthread.h>
  12#include <linux/slab.h>
  13#include <linux/migrate.h>
  14#include <linux/ratelimit.h>
  15#include <linux/uuid.h>
  16#include <linux/semaphore.h>
  17#include <linux/error-injection.h>
  18#include <linux/crc32c.h>
  19#include <linux/sched/mm.h>
  20#include <asm/unaligned.h>
  21#include <crypto/hash.h>
  22#include "ctree.h"
  23#include "disk-io.h"
  24#include "transaction.h"
  25#include "btrfs_inode.h"
  26#include "bio.h"
  27#include "print-tree.h"
  28#include "locking.h"
  29#include "tree-log.h"
  30#include "free-space-cache.h"
  31#include "free-space-tree.h"
 
  32#include "check-integrity.h"
  33#include "rcu-string.h"
  34#include "dev-replace.h"
  35#include "raid56.h"
  36#include "sysfs.h"
  37#include "qgroup.h"
  38#include "compression.h"
  39#include "tree-checker.h"
  40#include "ref-verify.h"
  41#include "block-group.h"
  42#include "discard.h"
  43#include "space-info.h"
  44#include "zoned.h"
  45#include "subpage.h"
  46#include "fs.h"
  47#include "accessors.h"
  48#include "extent-tree.h"
  49#include "root-tree.h"
  50#include "defrag.h"
  51#include "uuid-tree.h"
  52#include "relocation.h"
  53#include "scrub.h"
  54#include "super.h"
  55
  56#define BTRFS_SUPER_FLAG_SUPP	(BTRFS_HEADER_FLAG_WRITTEN |\
  57				 BTRFS_HEADER_FLAG_RELOC |\
  58				 BTRFS_SUPER_FLAG_ERROR |\
  59				 BTRFS_SUPER_FLAG_SEEDING |\
  60				 BTRFS_SUPER_FLAG_METADUMP |\
  61				 BTRFS_SUPER_FLAG_METADUMP_V2)
  62
 
 
  63static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
  64static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
  65				      struct btrfs_fs_info *fs_info);
  66static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
  67static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
  68					struct extent_io_tree *dirty_pages,
  69					int mark);
  70static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
  71				       struct extent_io_tree *pinned_extents);
  72static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info);
  73static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info);
  74
  75static void btrfs_free_csum_hash(struct btrfs_fs_info *fs_info)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  76{
  77	if (fs_info->csum_shash)
  78		crypto_free_shash(fs_info->csum_shash);
  79}
  80
  81/*
  82 * async submit bios are used to offload expensive checksumming
  83 * onto the worker threads.  They checksum file and metadata bios
  84 * just before they are sent down the IO stack.
  85 */
  86struct async_submit_bio {
  87	struct btrfs_inode *inode;
  88	struct bio *bio;
  89	enum btrfs_wq_submit_cmd submit_cmd;
  90	int mirror_num;
  91
  92	/* Optional parameter for used by direct io */
  93	u64 dio_file_offset;
 
 
  94	struct btrfs_work work;
  95	blk_status_t status;
  96};
  97
  98/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  99 * Compute the csum of a btree block and store the result to provided buffer.
 
 
 100 */
 101static void csum_tree_block(struct extent_buffer *buf, u8 *result)
 102{
 103	struct btrfs_fs_info *fs_info = buf->fs_info;
 104	const int num_pages = num_extent_pages(buf);
 105	const int first_page_part = min_t(u32, PAGE_SIZE, fs_info->nodesize);
 106	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 
 
 
 107	char *kaddr;
 108	int i;
 
 
 109
 110	shash->tfm = fs_info->csum_shash;
 111	crypto_shash_init(shash);
 112	kaddr = page_address(buf->pages[0]) + offset_in_page(buf->start);
 113	crypto_shash_update(shash, kaddr + BTRFS_CSUM_SIZE,
 114			    first_page_part - BTRFS_CSUM_SIZE);
 115
 116	for (i = 1; i < num_pages; i++) {
 117		kaddr = page_address(buf->pages[i]);
 118		crypto_shash_update(shash, kaddr, PAGE_SIZE);
 
 
 
 
 
 
 
 
 
 
 
 119	}
 120	memset(result, 0, BTRFS_CSUM_SIZE);
 
 121	crypto_shash_final(shash, result);
 
 
 122}
 123
 124/*
 125 * we can't consider a given block up to date unless the transid of the
 126 * block matches the transid in the parent node's pointer.  This is how we
 127 * detect blocks that either didn't get written at all or got written
 128 * in the wrong place.
 129 */
 130static int verify_parent_transid(struct extent_io_tree *io_tree,
 131				 struct extent_buffer *eb, u64 parent_transid,
 132				 int atomic)
 133{
 134	struct extent_state *cached_state = NULL;
 135	int ret;
 
 136
 137	if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 138		return 0;
 139
 140	if (atomic)
 141		return -EAGAIN;
 142
 143	lock_extent(io_tree, eb->start, eb->start + eb->len - 1, &cached_state);
 
 
 
 
 
 
 144	if (extent_buffer_uptodate(eb) &&
 145	    btrfs_header_generation(eb) == parent_transid) {
 146		ret = 0;
 147		goto out;
 148	}
 149	btrfs_err_rl(eb->fs_info,
 150"parent transid verify failed on logical %llu mirror %u wanted %llu found %llu",
 151			eb->start, eb->read_mirror,
 152			parent_transid, btrfs_header_generation(eb));
 153	ret = 1;
 154	clear_extent_buffer_uptodate(eb);
 
 
 
 
 
 
 
 
 
 
 155out:
 156	unlock_extent(io_tree, eb->start, eb->start + eb->len - 1,
 157		      &cached_state);
 
 
 158	return ret;
 159}
 160
 161static bool btrfs_supported_super_csum(u16 csum_type)
 162{
 163	switch (csum_type) {
 164	case BTRFS_CSUM_TYPE_CRC32:
 165	case BTRFS_CSUM_TYPE_XXHASH:
 166	case BTRFS_CSUM_TYPE_SHA256:
 167	case BTRFS_CSUM_TYPE_BLAKE2:
 168		return true;
 169	default:
 170		return false;
 171	}
 172}
 173
 174/*
 175 * Return 0 if the superblock checksum type matches the checksum value of that
 176 * algorithm. Pass the raw disk superblock data.
 177 */
 178int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
 179			   const struct btrfs_super_block *disk_sb)
 180{
 
 
 181	char result[BTRFS_CSUM_SIZE];
 182	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 183
 184	shash->tfm = fs_info->csum_shash;
 
 185
 186	/*
 187	 * The super_block structure does not span the whole
 188	 * BTRFS_SUPER_INFO_SIZE range, we expect that the unused space is
 189	 * filled with zeros and is included in the checksum.
 190	 */
 191	crypto_shash_digest(shash, (const u8 *)disk_sb + BTRFS_CSUM_SIZE,
 192			    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE, result);
 
 193
 194	if (memcmp(disk_sb->csum, result, fs_info->csum_size))
 195		return 1;
 196
 197	return 0;
 198}
 199
 200int btrfs_verify_level_key(struct extent_buffer *eb, int level,
 201			   struct btrfs_key *first_key, u64 parent_transid)
 202{
 203	struct btrfs_fs_info *fs_info = eb->fs_info;
 204	int found_level;
 205	struct btrfs_key found_key;
 206	int ret;
 207
 208	found_level = btrfs_header_level(eb);
 209	if (found_level != level) {
 210		WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
 211		     KERN_ERR "BTRFS: tree level check failed\n");
 212		btrfs_err(fs_info,
 213"tree level mismatch detected, bytenr=%llu level expected=%u has=%u",
 214			  eb->start, level, found_level);
 215		return -EIO;
 216	}
 217
 218	if (!first_key)
 219		return 0;
 220
 221	/*
 222	 * For live tree block (new tree blocks in current transaction),
 223	 * we need proper lock context to avoid race, which is impossible here.
 224	 * So we only checks tree blocks which is read from disk, whose
 225	 * generation <= fs_info->last_trans_committed.
 226	 */
 227	if (btrfs_header_generation(eb) > fs_info->last_trans_committed)
 228		return 0;
 229
 230	/* We have @first_key, so this @eb must have at least one item */
 231	if (btrfs_header_nritems(eb) == 0) {
 232		btrfs_err(fs_info,
 233		"invalid tree nritems, bytenr=%llu nritems=0 expect >0",
 234			  eb->start);
 235		WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
 236		return -EUCLEAN;
 237	}
 238
 239	if (found_level)
 240		btrfs_node_key_to_cpu(eb, &found_key, 0);
 241	else
 242		btrfs_item_key_to_cpu(eb, &found_key, 0);
 243	ret = btrfs_comp_cpu_keys(first_key, &found_key);
 244
 245	if (ret) {
 246		WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
 247		     KERN_ERR "BTRFS: tree first key check failed\n");
 248		btrfs_err(fs_info,
 249"tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
 250			  eb->start, parent_transid, first_key->objectid,
 251			  first_key->type, first_key->offset,
 252			  found_key.objectid, found_key.type,
 253			  found_key.offset);
 254	}
 255	return ret;
 256}
 257
 258static int btrfs_repair_eb_io_failure(const struct extent_buffer *eb,
 259				      int mirror_num)
 260{
 261	struct btrfs_fs_info *fs_info = eb->fs_info;
 262	u64 start = eb->start;
 263	int i, num_pages = num_extent_pages(eb);
 264	int ret = 0;
 265
 266	if (sb_rdonly(fs_info->sb))
 267		return -EROFS;
 268
 269	for (i = 0; i < num_pages; i++) {
 270		struct page *p = eb->pages[i];
 271
 272		ret = btrfs_repair_io_failure(fs_info, 0, start, PAGE_SIZE,
 273				start, p, start - page_offset(p), mirror_num);
 274		if (ret)
 275			break;
 276		start += PAGE_SIZE;
 277	}
 278
 279	return ret;
 280}
 281
 282/*
 283 * helper to read a given tree block, doing retries as required when
 284 * the checksums don't match and we have alternate mirrors to try.
 285 *
 286 * @check:		expected tree parentness check, see the comments of the
 287 *			structure for details.
 
 288 */
 289int btrfs_read_extent_buffer(struct extent_buffer *eb,
 290			     struct btrfs_tree_parent_check *check)
 
 291{
 292	struct btrfs_fs_info *fs_info = eb->fs_info;
 
 293	int failed = 0;
 294	int ret;
 295	int num_copies = 0;
 296	int mirror_num = 0;
 297	int failed_mirror = 0;
 298
 299	ASSERT(check);
 300
 301	while (1) {
 302		clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 303		ret = read_extent_buffer_pages(eb, WAIT_COMPLETE, mirror_num, check);
 304		if (!ret)
 305			break;
 
 
 
 
 
 
 
 
 306
 307		num_copies = btrfs_num_copies(fs_info,
 308					      eb->start, eb->len);
 309		if (num_copies == 1)
 310			break;
 311
 312		if (!failed_mirror) {
 313			failed = 1;
 314			failed_mirror = eb->read_mirror;
 315		}
 316
 317		mirror_num++;
 318		if (mirror_num == failed_mirror)
 319			mirror_num++;
 320
 321		if (mirror_num > num_copies)
 322			break;
 323	}
 324
 325	if (failed && !ret && failed_mirror)
 326		btrfs_repair_eb_io_failure(eb, failed_mirror);
 327
 328	return ret;
 329}
 330
 331static int csum_one_extent_buffer(struct extent_buffer *eb)
 
 
 
 
 
 332{
 333	struct btrfs_fs_info *fs_info = eb->fs_info;
 
 334	u8 result[BTRFS_CSUM_SIZE];
 
 
 335	int ret;
 336
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 337	ASSERT(memcmp_extent_buffer(eb, fs_info->fs_devices->metadata_uuid,
 338				    offsetof(struct btrfs_header, fsid),
 339				    BTRFS_FSID_SIZE) == 0);
 340	csum_tree_block(eb, result);
 
 341
 342	if (btrfs_header_level(eb))
 343		ret = btrfs_check_node(eb);
 344	else
 345		ret = btrfs_check_leaf_full(eb);
 346
 347	if (ret < 0)
 348		goto error;
 349
 350	/*
 351	 * Also check the generation, the eb reached here must be newer than
 352	 * last committed. Or something seriously wrong happened.
 353	 */
 354	if (unlikely(btrfs_header_generation(eb) <= fs_info->last_trans_committed)) {
 355		ret = -EUCLEAN;
 356		btrfs_err(fs_info,
 357			"block=%llu bad generation, have %llu expect > %llu",
 358			  eb->start, btrfs_header_generation(eb),
 359			  fs_info->last_trans_committed);
 360		goto error;
 361	}
 362	write_extent_buffer(eb, result, 0, fs_info->csum_size);
 363
 364	return 0;
 365
 366error:
 367	btrfs_print_tree(eb, 0);
 368	btrfs_err(fs_info, "block=%llu write time tree block corruption detected",
 369		  eb->start);
 370	/*
 371	 * Be noisy if this is an extent buffer from a log tree. We don't abort
 372	 * a transaction in case there's a bad log tree extent buffer, we just
 373	 * fallback to a transaction commit. Still we want to know when there is
 374	 * a bad log tree extent buffer, as that may signal a bug somewhere.
 375	 */
 376	WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG) ||
 377		btrfs_header_owner(eb) == BTRFS_TREE_LOG_OBJECTID);
 378	return ret;
 379}
 380
 381/* Checksum all dirty extent buffers in one bio_vec */
 382static int csum_dirty_subpage_buffers(struct btrfs_fs_info *fs_info,
 383				      struct bio_vec *bvec)
 384{
 385	struct page *page = bvec->bv_page;
 386	u64 bvec_start = page_offset(page) + bvec->bv_offset;
 387	u64 cur;
 388	int ret = 0;
 389
 390	for (cur = bvec_start; cur < bvec_start + bvec->bv_len;
 391	     cur += fs_info->nodesize) {
 392		struct extent_buffer *eb;
 393		bool uptodate;
 394
 395		eb = find_extent_buffer(fs_info, cur);
 396		uptodate = btrfs_subpage_test_uptodate(fs_info, page, cur,
 397						       fs_info->nodesize);
 398
 399		/* A dirty eb shouldn't disappear from buffer_radix */
 400		if (WARN_ON(!eb))
 401			return -EUCLEAN;
 
 
 
 
 
 
 
 402
 403		if (WARN_ON(cur != btrfs_header_bytenr(eb))) {
 404			free_extent_buffer(eb);
 405			return -EUCLEAN;
 406		}
 407		if (WARN_ON(!uptodate)) {
 408			free_extent_buffer(eb);
 409			return -EUCLEAN;
 410		}
 411
 412		ret = csum_one_extent_buffer(eb);
 413		free_extent_buffer(eb);
 414		if (ret < 0)
 415			return ret;
 416	}
 417	return ret;
 418}
 419
 420/*
 421 * Checksum a dirty tree block before IO.  This has extra checks to make sure
 422 * we only fill in the checksum field in the first page of a multi-page block.
 423 * For subpage extent buffers we need bvec to also read the offset in the page.
 424 */
 425static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct bio_vec *bvec)
 426{
 427	struct page *page = bvec->bv_page;
 428	u64 start = page_offset(page);
 429	u64 found_start;
 
 430	struct extent_buffer *eb;
 
 
 
 
 
 
 431
 432	if (fs_info->nodesize < PAGE_SIZE)
 433		return csum_dirty_subpage_buffers(fs_info, bvec);
 434
 435	eb = (struct extent_buffer *)page->private;
 436	if (page != eb->pages[0])
 437		return 0;
 438
 439	found_start = btrfs_header_bytenr(eb);
 440
 441	if (test_bit(EXTENT_BUFFER_NO_CHECK, &eb->bflags)) {
 442		WARN_ON(found_start != 0);
 443		return 0;
 444	}
 445
 446	/*
 447	 * Please do not consolidate these warnings into a single if.
 448	 * It is useful to know what went wrong.
 449	 */
 450	if (WARN_ON(found_start != start))
 451		return -EUCLEAN;
 452	if (WARN_ON(!PageUptodate(page)))
 453		return -EUCLEAN;
 454
 455	return csum_one_extent_buffer(eb);
 456}
 
 457
 458static int check_tree_block_fsid(struct extent_buffer *eb)
 459{
 460	struct btrfs_fs_info *fs_info = eb->fs_info;
 461	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
 462	u8 fsid[BTRFS_FSID_SIZE];
 463	u8 *metadata_uuid;
 464
 465	read_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid),
 466			   BTRFS_FSID_SIZE);
 467	/*
 468	 * Checking the incompat flag is only valid for the current fs. For
 469	 * seed devices it's forbidden to have their uuid changed so reading
 470	 * ->fsid in this case is fine
 471	 */
 472	if (btrfs_fs_incompat(fs_info, METADATA_UUID))
 473		metadata_uuid = fs_devices->metadata_uuid;
 474	else
 475		metadata_uuid = fs_devices->fsid;
 476
 477	if (!memcmp(fsid, metadata_uuid, BTRFS_FSID_SIZE))
 478		return 0;
 479
 480	list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list)
 481		if (!memcmp(fsid, seed_devs->fsid, BTRFS_FSID_SIZE))
 482			return 0;
 483
 484	return 1;
 485}
 486
 487/* Do basic extent buffer checks at read time */
 488static int validate_extent_buffer(struct extent_buffer *eb,
 489				  struct btrfs_tree_parent_check *check)
 490{
 491	struct btrfs_fs_info *fs_info = eb->fs_info;
 492	u64 found_start;
 493	const u32 csum_size = fs_info->csum_size;
 494	u8 found_level;
 495	u8 result[BTRFS_CSUM_SIZE];
 496	const u8 *header_csum;
 497	int ret = 0;
 498
 499	ASSERT(check);
 500
 501	found_start = btrfs_header_bytenr(eb);
 502	if (found_start != eb->start) {
 503		btrfs_err_rl(fs_info,
 504			"bad tree block start, mirror %u want %llu have %llu",
 505			     eb->read_mirror, eb->start, found_start);
 506		ret = -EIO;
 507		goto out;
 508	}
 509	if (check_tree_block_fsid(eb)) {
 510		btrfs_err_rl(fs_info, "bad fsid on logical %llu mirror %u",
 511			     eb->start, eb->read_mirror);
 512		ret = -EIO;
 513		goto out;
 514	}
 515	found_level = btrfs_header_level(eb);
 516	if (found_level >= BTRFS_MAX_LEVEL) {
 517		btrfs_err(fs_info,
 518			"bad tree block level, mirror %u level %d on logical %llu",
 519			eb->read_mirror, btrfs_header_level(eb), eb->start);
 520		ret = -EIO;
 521		goto out;
 522	}
 523
 524	csum_tree_block(eb, result);
 525	header_csum = page_address(eb->pages[0]) +
 526		get_eb_offset_in_page(eb, offsetof(struct btrfs_header, csum));
 
 
 
 
 
 
 
 
 
 527
 528	if (memcmp(result, header_csum, csum_size) != 0) {
 529		btrfs_warn_rl(fs_info,
 530"checksum verify failed on logical %llu mirror %u wanted " CSUM_FMT " found " CSUM_FMT " level %d",
 531			      eb->start, eb->read_mirror,
 532			      CSUM_FMT_VALUE(csum_size, header_csum),
 533			      CSUM_FMT_VALUE(csum_size, result),
 534			      btrfs_header_level(eb));
 535		ret = -EUCLEAN;
 536		goto out;
 537	}
 538
 539	if (found_level != check->level) {
 540		btrfs_err(fs_info,
 541		"level verify failed on logical %llu mirror %u wanted %u found %u",
 542			  eb->start, eb->read_mirror, check->level, found_level);
 543		ret = -EIO;
 544		goto out;
 545	}
 546	if (unlikely(check->transid &&
 547		     btrfs_header_generation(eb) != check->transid)) {
 548		btrfs_err_rl(eb->fs_info,
 549"parent transid verify failed on logical %llu mirror %u wanted %llu found %llu",
 550				eb->start, eb->read_mirror, check->transid,
 551				btrfs_header_generation(eb));
 552		ret = -EIO;
 553		goto out;
 554	}
 555	if (check->has_first_key) {
 556		struct btrfs_key *expect_key = &check->first_key;
 557		struct btrfs_key found_key;
 558
 559		if (found_level)
 560			btrfs_node_key_to_cpu(eb, &found_key, 0);
 561		else
 562			btrfs_item_key_to_cpu(eb, &found_key, 0);
 563		if (unlikely(btrfs_comp_cpu_keys(expect_key, &found_key))) {
 564			btrfs_err(fs_info,
 565"tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
 566				  eb->start, check->transid,
 567				  expect_key->objectid,
 568				  expect_key->type, expect_key->offset,
 569				  found_key.objectid, found_key.type,
 570				  found_key.offset);
 571			ret = -EUCLEAN;
 572			goto out;
 573		}
 574	}
 575	if (check->owner_root) {
 576		ret = btrfs_check_eb_owner(eb, check->owner_root);
 577		if (ret < 0)
 578			goto out;
 579	}
 580
 581	/*
 582	 * If this is a leaf block and it is corrupt, set the corrupt bit so
 583	 * that we don't try and read the other copies of this block, just
 584	 * return -EIO.
 585	 */
 586	if (found_level == 0 && btrfs_check_leaf_full(eb)) {
 587		set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 588		ret = -EIO;
 589	}
 590
 591	if (found_level > 0 && btrfs_check_node(eb))
 592		ret = -EIO;
 593
 594	if (!ret)
 595		set_extent_buffer_uptodate(eb);
 596	else
 597		btrfs_err(fs_info,
 598		"read time tree block corruption detected on logical %llu mirror %u",
 599			  eb->start, eb->read_mirror);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 600out:
 601	return ret;
 602}
 603
 604static int validate_subpage_buffer(struct page *page, u64 start, u64 end,
 605				   int mirror, struct btrfs_tree_parent_check *check)
 606{
 607	struct btrfs_fs_info *fs_info = btrfs_sb(page->mapping->host->i_sb);
 608	struct extent_buffer *eb;
 609	bool reads_done;
 610	int ret = 0;
 611
 612	ASSERT(check);
 
 613
 614	/*
 615	 * We don't allow bio merge for subpage metadata read, so we should
 616	 * only get one eb for each endio hook.
 617	 */
 618	ASSERT(end == start + fs_info->nodesize - 1);
 619	ASSERT(PagePrivate(page));
 620
 621	eb = find_extent_buffer(fs_info, start);
 622	/*
 623	 * When we are reading one tree block, eb must have been inserted into
 624	 * the radix tree. If not, something is wrong.
 625	 */
 626	ASSERT(eb);
 627
 628	reads_done = atomic_dec_and_test(&eb->io_pages);
 629	/* Subpage read must finish in page read */
 630	ASSERT(reads_done);
 631
 632	eb->read_mirror = mirror;
 633	if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
 634		ret = -EIO;
 635		goto err;
 
 
 
 
 
 
 
 636	}
 637	ret = validate_extent_buffer(eb, check);
 638	if (ret < 0)
 639		goto err;
 640
 641	set_extent_buffer_uptodate(eb);
 642
 643	free_extent_buffer(eb);
 644	return ret;
 645err:
 646	/*
 647	 * end_bio_extent_readpage decrements io_pages in case of error,
 648	 * make sure it has something to decrement.
 649	 */
 650	atomic_inc(&eb->io_pages);
 651	clear_extent_buffer_uptodate(eb);
 652	free_extent_buffer(eb);
 653	return ret;
 654}
 655
 656int btrfs_validate_metadata_buffer(struct btrfs_bio *bbio,
 657				   struct page *page, u64 start, u64 end,
 658				   int mirror)
 659{
 660	struct extent_buffer *eb;
 661	int ret = 0;
 662	int reads_done;
 663
 664	ASSERT(page->private);
 
 
 665
 666	if (btrfs_sb(page->mapping->host->i_sb)->nodesize < PAGE_SIZE)
 667		return validate_subpage_buffer(page, start, end, mirror,
 668					       &bbio->parent_check);
 
 
 
 669
 670	eb = (struct extent_buffer *)page->private;
 671
 672	/*
 673	 * The pending IO might have been the only thing that kept this buffer
 674	 * in memory.  Make sure we have a ref for all this other checks
 675	 */
 676	atomic_inc(&eb->refs);
 677
 678	reads_done = atomic_dec_and_test(&eb->io_pages);
 679	if (!reads_done)
 680		goto err;
 681
 682	eb->read_mirror = mirror;
 683	if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
 684		ret = -EIO;
 685		goto err;
 686	}
 687	ret = validate_extent_buffer(eb, &bbio->parent_check);
 688err:
 689	if (ret) {
 690		/*
 691		 * our io error hook is going to dec the io pages
 692		 * again, we have to make sure it has something
 693		 * to decrement
 694		 */
 695		atomic_inc(&eb->io_pages);
 696		clear_extent_buffer_uptodate(eb);
 697	}
 698	free_extent_buffer(eb);
 699
 700	return ret;
 701}
 702
 703static void run_one_async_start(struct btrfs_work *work)
 704{
 705	struct async_submit_bio *async;
 706	blk_status_t ret;
 707
 708	async = container_of(work, struct  async_submit_bio, work);
 709	switch (async->submit_cmd) {
 710	case WQ_SUBMIT_METADATA:
 711		ret = btree_submit_bio_start(async->bio);
 712		break;
 713	case WQ_SUBMIT_DATA:
 714		ret = btrfs_submit_bio_start(async->inode, async->bio);
 715		break;
 716	case WQ_SUBMIT_DATA_DIO:
 717		ret = btrfs_submit_bio_start_direct_io(async->inode,
 718				async->bio, async->dio_file_offset);
 719		break;
 720	}
 721	if (ret)
 722		async->status = ret;
 723}
 724
 725/*
 726 * In order to insert checksums into the metadata in large chunks, we wait
 727 * until bio submission time.   All the pages in the bio are checksummed and
 728 * sums are attached onto the ordered extent record.
 729 *
 730 * At IO completion time the csums attached on the ordered extent record are
 731 * inserted into the tree.
 732 */
 733static void run_one_async_done(struct btrfs_work *work)
 734{
 735	struct async_submit_bio *async =
 736		container_of(work, struct  async_submit_bio, work);
 737	struct btrfs_inode *inode = async->inode;
 738	struct btrfs_bio *bbio = btrfs_bio(async->bio);
 
 
 739
 740	/* If an error occurred we just want to clean up the bio and move on */
 741	if (async->status) {
 742		btrfs_bio_end_io(bbio, async->status);
 
 743		return;
 744	}
 745
 746	/*
 747	 * All of the bios that pass through here are from async helpers.
 748	 * Use REQ_CGROUP_PUNT to issue them from the owning cgroup's context.
 749	 * This changes nothing when cgroups aren't in use.
 750	 */
 751	async->bio->bi_opf |= REQ_CGROUP_PUNT;
 752	btrfs_submit_bio(inode->root->fs_info, async->bio, async->mirror_num);
 753}
 754
 755static void run_one_async_free(struct btrfs_work *work)
 756{
 757	struct async_submit_bio *async;
 758
 759	async = container_of(work, struct  async_submit_bio, work);
 760	kfree(async);
 761}
 762
 763/*
 764 * Submit bio to an async queue.
 765 *
 766 * Retrun:
 767 * - true if the work has been succesfuly submitted
 768 * - false in case of error
 769 */
 770bool btrfs_wq_submit_bio(struct btrfs_inode *inode, struct bio *bio, int mirror_num,
 771			 u64 dio_file_offset, enum btrfs_wq_submit_cmd cmd)
 772{
 773	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 774	struct async_submit_bio *async;
 775
 776	async = kmalloc(sizeof(*async), GFP_NOFS);
 777	if (!async)
 778		return false;
 779
 780	async->inode = inode;
 781	async->bio = bio;
 782	async->mirror_num = mirror_num;
 783	async->submit_cmd = cmd;
 784
 785	btrfs_init_work(&async->work, run_one_async_start, run_one_async_done,
 786			run_one_async_free);
 787
 788	async->dio_file_offset = dio_file_offset;
 789
 790	async->status = 0;
 791
 792	if (op_is_sync(bio->bi_opf))
 793		btrfs_queue_work(fs_info->hipri_workers, &async->work);
 794	else
 795		btrfs_queue_work(fs_info->workers, &async->work);
 796	return true;
 797}
 798
 799static blk_status_t btree_csum_one_bio(struct bio *bio)
 800{
 801	struct bio_vec *bvec;
 802	struct btrfs_root *root;
 803	int ret = 0;
 804	struct bvec_iter_all iter_all;
 805
 806	ASSERT(!bio_flagged(bio, BIO_CLONED));
 807	bio_for_each_segment_all(bvec, bio, iter_all) {
 808		root = BTRFS_I(bvec->bv_page->mapping->host)->root;
 809		ret = csum_dirty_buffer(root->fs_info, bvec);
 810		if (ret)
 811			break;
 812	}
 813
 814	return errno_to_blk_status(ret);
 815}
 816
 817blk_status_t btree_submit_bio_start(struct bio *bio)
 
 818{
 819	/*
 820	 * when we're called for a write, we're already in the async
 821	 * submission context.  Just jump into btrfs_submit_bio.
 822	 */
 823	return btree_csum_one_bio(bio);
 824}
 825
 826static bool should_async_write(struct btrfs_fs_info *fs_info,
 827			     struct btrfs_inode *bi)
 828{
 829	if (btrfs_is_zoned(fs_info))
 830		return false;
 831	if (atomic_read(&bi->sync_writers))
 832		return false;
 833	if (test_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags))
 834		return false;
 835	return true;
 836}
 837
 838void btrfs_submit_metadata_bio(struct btrfs_inode *inode, struct bio *bio, int mirror_num)
 
 
 839{
 840	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 841	struct btrfs_bio *bbio = btrfs_bio(bio);
 842	blk_status_t ret;
 843
 844	bio->bi_opf |= REQ_META;
 845	bbio->is_metadata = 1;
 846
 847	if (btrfs_op(bio) != BTRFS_MAP_WRITE) {
 848		btrfs_submit_bio(fs_info, bio, mirror_num);
 849		return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 850	}
 851
 852	/*
 853	 * Kthread helpers are used to submit writes so that checksumming can
 854	 * happen in parallel across all CPUs.
 855	 */
 856	if (should_async_write(fs_info, inode) &&
 857	    btrfs_wq_submit_bio(inode, bio, mirror_num, 0, WQ_SUBMIT_METADATA))
 858		return;
 859
 860	ret = btree_csum_one_bio(bio);
 861	if (ret) {
 862		btrfs_bio_end_io(bbio, ret);
 863		return;
 864	}
 865
 866	btrfs_submit_bio(fs_info, bio, mirror_num);
 867}
 868
 869#ifdef CONFIG_MIGRATION
 870static int btree_migrate_folio(struct address_space *mapping,
 871		struct folio *dst, struct folio *src, enum migrate_mode mode)
 
 872{
 873	/*
 874	 * we can't safely write a btree page from here,
 875	 * we haven't done the locking hook
 876	 */
 877	if (folio_test_dirty(src))
 878		return -EAGAIN;
 879	/*
 880	 * Buffers may be managed in a filesystem specific way.
 881	 * We must have no buffers or drop them.
 882	 */
 883	if (folio_get_private(src) &&
 884	    !filemap_release_folio(src, GFP_KERNEL))
 885		return -EAGAIN;
 886	return migrate_folio(mapping, dst, src, mode);
 887}
 888#else
 889#define btree_migrate_folio NULL
 890#endif
 891
 
 892static int btree_writepages(struct address_space *mapping,
 893			    struct writeback_control *wbc)
 894{
 895	struct btrfs_fs_info *fs_info;
 896	int ret;
 897
 898	if (wbc->sync_mode == WB_SYNC_NONE) {
 899
 900		if (wbc->for_kupdate)
 901			return 0;
 902
 903		fs_info = BTRFS_I(mapping->host)->root->fs_info;
 904		/* this is a bit racy, but that's ok */
 905		ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
 906					     BTRFS_DIRTY_METADATA_THRESH,
 907					     fs_info->dirty_metadata_batch);
 908		if (ret < 0)
 909			return 0;
 910	}
 911	return btree_write_cache_pages(mapping, wbc);
 912}
 913
 914static bool btree_release_folio(struct folio *folio, gfp_t gfp_flags)
 
 
 
 
 
 
 
 915{
 916	if (folio_test_writeback(folio) || folio_test_dirty(folio))
 917		return false;
 918
 919	return try_release_extent_buffer(&folio->page);
 920}
 921
 922static void btree_invalidate_folio(struct folio *folio, size_t offset,
 923				 size_t length)
 924{
 925	struct extent_io_tree *tree;
 926	tree = &BTRFS_I(folio->mapping->host)->io_tree;
 927	extent_invalidate_folio(tree, folio, offset);
 928	btree_release_folio(folio, GFP_NOFS);
 929	if (folio_get_private(folio)) {
 930		btrfs_warn(BTRFS_I(folio->mapping->host)->root->fs_info,
 931			   "folio private not zero on folio %llu",
 932			   (unsigned long long)folio_pos(folio));
 933		folio_detach_private(folio);
 
 
 934	}
 935}
 936
 
 
 937#ifdef DEBUG
 938static bool btree_dirty_folio(struct address_space *mapping,
 939		struct folio *folio)
 940{
 941	struct btrfs_fs_info *fs_info = btrfs_sb(mapping->host->i_sb);
 942	struct btrfs_subpage *subpage;
 943	struct extent_buffer *eb;
 944	int cur_bit = 0;
 945	u64 page_start = folio_pos(folio);
 946
 947	if (fs_info->sectorsize == PAGE_SIZE) {
 948		eb = folio_get_private(folio);
 949		BUG_ON(!eb);
 950		BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
 951		BUG_ON(!atomic_read(&eb->refs));
 952		btrfs_assert_tree_write_locked(eb);
 953		return filemap_dirty_folio(mapping, folio);
 954	}
 955	subpage = folio_get_private(folio);
 956
 957	ASSERT(subpage->dirty_bitmap);
 958	while (cur_bit < BTRFS_SUBPAGE_BITMAP_SIZE) {
 959		unsigned long flags;
 960		u64 cur;
 961		u16 tmp = (1 << cur_bit);
 962
 963		spin_lock_irqsave(&subpage->lock, flags);
 964		if (!(tmp & subpage->dirty_bitmap)) {
 965			spin_unlock_irqrestore(&subpage->lock, flags);
 966			cur_bit++;
 967			continue;
 968		}
 969		spin_unlock_irqrestore(&subpage->lock, flags);
 970		cur = page_start + cur_bit * fs_info->sectorsize;
 971
 972		eb = find_extent_buffer(fs_info, cur);
 973		ASSERT(eb);
 974		ASSERT(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
 975		ASSERT(atomic_read(&eb->refs));
 976		btrfs_assert_tree_write_locked(eb);
 977		free_extent_buffer(eb);
 978
 979		cur_bit += (fs_info->nodesize >> fs_info->sectorsize_bits);
 980	}
 981	return filemap_dirty_folio(mapping, folio);
 982}
 983#else
 984#define btree_dirty_folio filemap_dirty_folio
 985#endif
 986
 987static const struct address_space_operations btree_aops = {
 
 988	.writepages	= btree_writepages,
 989	.release_folio	= btree_release_folio,
 990	.invalidate_folio = btree_invalidate_folio,
 991	.migrate_folio	= btree_migrate_folio,
 992	.dirty_folio	= btree_dirty_folio,
 
 
 993};
 994
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 995struct extent_buffer *btrfs_find_create_tree_block(
 996						struct btrfs_fs_info *fs_info,
 997						u64 bytenr, u64 owner_root,
 998						int level)
 999{
1000	if (btrfs_is_testing(fs_info))
1001		return alloc_test_extent_buffer(fs_info, bytenr);
1002	return alloc_extent_buffer(fs_info, bytenr, owner_root, level);
1003}
1004
1005/*
1006 * Read tree block at logical address @bytenr and do variant basic but critical
1007 * verification.
1008 *
1009 * @check:		expected tree parentness check, see comments of the
1010 *			structure for details.
 
1011 */
1012struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
1013				      struct btrfs_tree_parent_check *check)
 
1014{
1015	struct extent_buffer *buf = NULL;
1016	int ret;
1017
1018	ASSERT(check);
1019
1020	buf = btrfs_find_create_tree_block(fs_info, bytenr, check->owner_root,
1021					   check->level);
1022	if (IS_ERR(buf))
1023		return buf;
1024
1025	ret = btrfs_read_extent_buffer(buf, check);
 
1026	if (ret) {
1027		free_extent_buffer_stale(buf);
1028		return ERR_PTR(ret);
1029	}
1030	if (btrfs_check_eb_owner(buf, check->owner_root)) {
1031		free_extent_buffer_stale(buf);
1032		return ERR_PTR(-EUCLEAN);
1033	}
1034	return buf;
1035
1036}
1037
1038void btrfs_clean_tree_block(struct extent_buffer *buf)
1039{
1040	struct btrfs_fs_info *fs_info = buf->fs_info;
1041	if (btrfs_header_generation(buf) ==
1042	    fs_info->running_transaction->transid) {
1043		btrfs_assert_tree_write_locked(buf);
1044
1045		if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
1046			percpu_counter_add_batch(&fs_info->dirty_metadata_bytes,
1047						 -buf->len,
1048						 fs_info->dirty_metadata_batch);
 
 
1049			clear_extent_buffer_dirty(buf);
1050		}
1051	}
1052}
1053
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1054static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
1055			 u64 objectid)
1056{
1057	bool dummy = test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state);
1058
1059	memset(&root->root_key, 0, sizeof(root->root_key));
1060	memset(&root->root_item, 0, sizeof(root->root_item));
1061	memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
1062	root->fs_info = fs_info;
1063	root->root_key.objectid = objectid;
1064	root->node = NULL;
1065	root->commit_root = NULL;
1066	root->state = 0;
1067	RB_CLEAR_NODE(&root->rb_node);
1068
1069	root->last_trans = 0;
1070	root->free_objectid = 0;
1071	root->nr_delalloc_inodes = 0;
1072	root->nr_ordered_extents = 0;
1073	root->inode_tree = RB_ROOT;
1074	INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
1075
1076	btrfs_init_root_block_rsv(root);
1077
1078	INIT_LIST_HEAD(&root->dirty_list);
1079	INIT_LIST_HEAD(&root->root_list);
1080	INIT_LIST_HEAD(&root->delalloc_inodes);
1081	INIT_LIST_HEAD(&root->delalloc_root);
1082	INIT_LIST_HEAD(&root->ordered_extents);
1083	INIT_LIST_HEAD(&root->ordered_root);
1084	INIT_LIST_HEAD(&root->reloc_dirty_list);
1085	INIT_LIST_HEAD(&root->logged_list[0]);
1086	INIT_LIST_HEAD(&root->logged_list[1]);
1087	spin_lock_init(&root->inode_lock);
1088	spin_lock_init(&root->delalloc_lock);
1089	spin_lock_init(&root->ordered_extent_lock);
1090	spin_lock_init(&root->accounting_lock);
1091	spin_lock_init(&root->log_extents_lock[0]);
1092	spin_lock_init(&root->log_extents_lock[1]);
1093	spin_lock_init(&root->qgroup_meta_rsv_lock);
1094	mutex_init(&root->objectid_mutex);
1095	mutex_init(&root->log_mutex);
1096	mutex_init(&root->ordered_extent_mutex);
1097	mutex_init(&root->delalloc_mutex);
1098	init_waitqueue_head(&root->qgroup_flush_wait);
1099	init_waitqueue_head(&root->log_writer_wait);
1100	init_waitqueue_head(&root->log_commit_wait[0]);
1101	init_waitqueue_head(&root->log_commit_wait[1]);
1102	INIT_LIST_HEAD(&root->log_ctxs[0]);
1103	INIT_LIST_HEAD(&root->log_ctxs[1]);
1104	atomic_set(&root->log_commit[0], 0);
1105	atomic_set(&root->log_commit[1], 0);
1106	atomic_set(&root->log_writers, 0);
1107	atomic_set(&root->log_batch, 0);
1108	refcount_set(&root->refs, 1);
 
1109	atomic_set(&root->snapshot_force_cow, 0);
1110	atomic_set(&root->nr_swapfiles, 0);
1111	root->log_transid = 0;
1112	root->log_transid_committed = -1;
1113	root->last_log_commit = 0;
 
 
 
 
 
 
 
 
 
 
 
 
1114	root->anon_dev = 0;
1115	if (!dummy) {
1116		extent_io_tree_init(fs_info, &root->dirty_log_pages,
1117				    IO_TREE_ROOT_DIRTY_LOG_PAGES);
1118		extent_io_tree_init(fs_info, &root->log_csum_range,
1119				    IO_TREE_LOG_CSUM_RANGE);
1120	}
1121
1122	spin_lock_init(&root->root_item_lock);
1123	btrfs_qgroup_init_swapped_blocks(&root->swapped_blocks);
1124#ifdef CONFIG_BTRFS_DEBUG
1125	INIT_LIST_HEAD(&root->leak_list);
1126	spin_lock(&fs_info->fs_roots_radix_lock);
1127	list_add_tail(&root->leak_list, &fs_info->allocated_roots);
1128	spin_unlock(&fs_info->fs_roots_radix_lock);
1129#endif
1130}
1131
1132static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info,
1133					   u64 objectid, gfp_t flags)
1134{
1135	struct btrfs_root *root = kzalloc(sizeof(*root), flags);
1136	if (root)
1137		__setup_root(root, fs_info, objectid);
1138	return root;
1139}
1140
1141#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
1142/* Should only be used by the testing infrastructure */
1143struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info)
1144{
1145	struct btrfs_root *root;
1146
1147	if (!fs_info)
1148		return ERR_PTR(-EINVAL);
1149
1150	root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID, GFP_KERNEL);
1151	if (!root)
1152		return ERR_PTR(-ENOMEM);
1153
1154	/* We don't use the stripesize in selftest, set it as sectorsize */
 
1155	root->alloc_bytenr = 0;
1156
1157	return root;
1158}
1159#endif
1160
1161static int global_root_cmp(struct rb_node *a_node, const struct rb_node *b_node)
1162{
1163	const struct btrfs_root *a = rb_entry(a_node, struct btrfs_root, rb_node);
1164	const struct btrfs_root *b = rb_entry(b_node, struct btrfs_root, rb_node);
1165
1166	return btrfs_comp_cpu_keys(&a->root_key, &b->root_key);
1167}
1168
1169static int global_root_key_cmp(const void *k, const struct rb_node *node)
1170{
1171	const struct btrfs_key *key = k;
1172	const struct btrfs_root *root = rb_entry(node, struct btrfs_root, rb_node);
1173
1174	return btrfs_comp_cpu_keys(key, &root->root_key);
1175}
1176
1177int btrfs_global_root_insert(struct btrfs_root *root)
1178{
1179	struct btrfs_fs_info *fs_info = root->fs_info;
1180	struct rb_node *tmp;
1181
1182	write_lock(&fs_info->global_root_lock);
1183	tmp = rb_find_add(&root->rb_node, &fs_info->global_root_tree, global_root_cmp);
1184	write_unlock(&fs_info->global_root_lock);
1185	ASSERT(!tmp);
1186
1187	return tmp ? -EEXIST : 0;
1188}
1189
1190void btrfs_global_root_delete(struct btrfs_root *root)
1191{
1192	struct btrfs_fs_info *fs_info = root->fs_info;
1193
1194	write_lock(&fs_info->global_root_lock);
1195	rb_erase(&root->rb_node, &fs_info->global_root_tree);
1196	write_unlock(&fs_info->global_root_lock);
1197}
1198
1199struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info,
1200				     struct btrfs_key *key)
1201{
1202	struct rb_node *node;
1203	struct btrfs_root *root = NULL;
1204
1205	read_lock(&fs_info->global_root_lock);
1206	node = rb_find(key, &fs_info->global_root_tree, global_root_key_cmp);
1207	if (node)
1208		root = container_of(node, struct btrfs_root, rb_node);
1209	read_unlock(&fs_info->global_root_lock);
1210
1211	return root;
1212}
1213
1214static u64 btrfs_global_root_id(struct btrfs_fs_info *fs_info, u64 bytenr)
1215{
1216	struct btrfs_block_group *block_group;
1217	u64 ret;
1218
1219	if (!btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
1220		return 0;
1221
1222	if (bytenr)
1223		block_group = btrfs_lookup_block_group(fs_info, bytenr);
1224	else
1225		block_group = btrfs_lookup_first_block_group(fs_info, bytenr);
1226	ASSERT(block_group);
1227	if (!block_group)
1228		return 0;
1229	ret = block_group->global_root_id;
1230	btrfs_put_block_group(block_group);
1231
1232	return ret;
1233}
1234
1235struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr)
1236{
1237	struct btrfs_key key = {
1238		.objectid = BTRFS_CSUM_TREE_OBJECTID,
1239		.type = BTRFS_ROOT_ITEM_KEY,
1240		.offset = btrfs_global_root_id(fs_info, bytenr),
1241	};
1242
1243	return btrfs_global_root(fs_info, &key);
1244}
1245
1246struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr)
1247{
1248	struct btrfs_key key = {
1249		.objectid = BTRFS_EXTENT_TREE_OBJECTID,
1250		.type = BTRFS_ROOT_ITEM_KEY,
1251		.offset = btrfs_global_root_id(fs_info, bytenr),
1252	};
1253
1254	return btrfs_global_root(fs_info, &key);
1255}
1256
1257struct btrfs_root *btrfs_block_group_root(struct btrfs_fs_info *fs_info)
1258{
1259	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE))
1260		return fs_info->block_group_root;
1261	return btrfs_extent_root(fs_info, 0);
1262}
1263
1264struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
1265				     u64 objectid)
1266{
1267	struct btrfs_fs_info *fs_info = trans->fs_info;
1268	struct extent_buffer *leaf;
1269	struct btrfs_root *tree_root = fs_info->tree_root;
1270	struct btrfs_root *root;
1271	struct btrfs_key key;
1272	unsigned int nofs_flag;
1273	int ret = 0;
 
1274
1275	/*
1276	 * We're holding a transaction handle, so use a NOFS memory allocation
1277	 * context to avoid deadlock if reclaim happens.
1278	 */
1279	nofs_flag = memalloc_nofs_save();
1280	root = btrfs_alloc_root(fs_info, objectid, GFP_KERNEL);
1281	memalloc_nofs_restore(nofs_flag);
1282	if (!root)
1283		return ERR_PTR(-ENOMEM);
1284
 
1285	root->root_key.objectid = objectid;
1286	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1287	root->root_key.offset = 0;
1288
1289	leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0,
1290				      BTRFS_NESTING_NORMAL);
1291	if (IS_ERR(leaf)) {
1292		ret = PTR_ERR(leaf);
1293		leaf = NULL;
1294		goto fail;
1295	}
1296
1297	root->node = leaf;
1298	btrfs_mark_buffer_dirty(leaf);
1299
1300	root->commit_root = btrfs_root_node(root);
1301	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
1302
1303	btrfs_set_root_flags(&root->root_item, 0);
1304	btrfs_set_root_limit(&root->root_item, 0);
1305	btrfs_set_root_bytenr(&root->root_item, leaf->start);
1306	btrfs_set_root_generation(&root->root_item, trans->transid);
1307	btrfs_set_root_level(&root->root_item, 0);
1308	btrfs_set_root_refs(&root->root_item, 1);
1309	btrfs_set_root_used(&root->root_item, leaf->len);
1310	btrfs_set_root_last_snapshot(&root->root_item, 0);
1311	btrfs_set_root_dirid(&root->root_item, 0);
1312	if (is_fstree(objectid))
1313		generate_random_guid(root->root_item.uuid);
1314	else
1315		export_guid(root->root_item.uuid, &guid_null);
1316	btrfs_set_root_drop_level(&root->root_item, 0);
1317
1318	btrfs_tree_unlock(leaf);
1319
1320	key.objectid = objectid;
1321	key.type = BTRFS_ROOT_ITEM_KEY;
1322	key.offset = 0;
1323	ret = btrfs_insert_root(trans, tree_root, &key, &root->root_item);
1324	if (ret)
1325		goto fail;
1326
 
 
1327	return root;
1328
1329fail:
1330	btrfs_put_root(root);
 
 
 
 
 
1331
1332	return ERR_PTR(ret);
1333}
1334
1335static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
1336					 struct btrfs_fs_info *fs_info)
1337{
1338	struct btrfs_root *root;
 
1339
1340	root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID, GFP_NOFS);
1341	if (!root)
1342		return ERR_PTR(-ENOMEM);
1343
 
 
1344	root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1345	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1346	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
1347
1348	return root;
1349}
1350
1351int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
1352			      struct btrfs_root *root)
1353{
1354	struct extent_buffer *leaf;
1355
1356	/*
1357	 * DON'T set SHAREABLE bit for log trees.
1358	 *
1359	 * Log trees are not exposed to user space thus can't be snapshotted,
1360	 * and they go away before a real commit is actually done.
1361	 *
1362	 * They do store pointers to file data extents, and those reference
1363	 * counts still get updated (along with back refs to the log tree).
 
 
1364	 */
1365
1366	leaf = btrfs_alloc_tree_block(trans, root, 0, BTRFS_TREE_LOG_OBJECTID,
1367			NULL, 0, 0, 0, BTRFS_NESTING_NORMAL);
1368	if (IS_ERR(leaf))
1369		return PTR_ERR(leaf);
 
 
1370
1371	root->node = leaf;
1372
1373	btrfs_mark_buffer_dirty(root->node);
1374	btrfs_tree_unlock(root->node);
1375
1376	return 0;
1377}
1378
1379int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1380			     struct btrfs_fs_info *fs_info)
1381{
1382	struct btrfs_root *log_root;
1383
1384	log_root = alloc_log_tree(trans, fs_info);
1385	if (IS_ERR(log_root))
1386		return PTR_ERR(log_root);
1387
1388	if (!btrfs_is_zoned(fs_info)) {
1389		int ret = btrfs_alloc_log_tree_node(trans, log_root);
1390
1391		if (ret) {
1392			btrfs_put_root(log_root);
1393			return ret;
1394		}
1395	}
1396
1397	WARN_ON(fs_info->log_root_tree);
1398	fs_info->log_root_tree = log_root;
1399	return 0;
1400}
1401
1402int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1403		       struct btrfs_root *root)
1404{
1405	struct btrfs_fs_info *fs_info = root->fs_info;
1406	struct btrfs_root *log_root;
1407	struct btrfs_inode_item *inode_item;
1408	int ret;
1409
1410	log_root = alloc_log_tree(trans, fs_info);
1411	if (IS_ERR(log_root))
1412		return PTR_ERR(log_root);
1413
1414	ret = btrfs_alloc_log_tree_node(trans, log_root);
1415	if (ret) {
1416		btrfs_put_root(log_root);
1417		return ret;
1418	}
1419
1420	log_root->last_trans = trans->transid;
1421	log_root->root_key.offset = root->root_key.objectid;
1422
1423	inode_item = &log_root->root_item.inode;
1424	btrfs_set_stack_inode_generation(inode_item, 1);
1425	btrfs_set_stack_inode_size(inode_item, 3);
1426	btrfs_set_stack_inode_nlink(inode_item, 1);
1427	btrfs_set_stack_inode_nbytes(inode_item,
1428				     fs_info->nodesize);
1429	btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
1430
1431	btrfs_set_root_node(&log_root->root_item, log_root->node);
1432
1433	WARN_ON(root->log_root);
1434	root->log_root = log_root;
1435	root->log_transid = 0;
1436	root->log_transid_committed = -1;
1437	root->last_log_commit = 0;
1438	return 0;
1439}
1440
1441static struct btrfs_root *read_tree_root_path(struct btrfs_root *tree_root,
1442					      struct btrfs_path *path,
1443					      struct btrfs_key *key)
1444{
1445	struct btrfs_root *root;
1446	struct btrfs_tree_parent_check check = { 0 };
1447	struct btrfs_fs_info *fs_info = tree_root->fs_info;
 
1448	u64 generation;
1449	int ret;
1450	int level;
1451
1452	root = btrfs_alloc_root(fs_info, key->objectid, GFP_NOFS);
1453	if (!root)
1454		return ERR_PTR(-ENOMEM);
1455
 
 
 
 
 
 
 
 
1456	ret = btrfs_find_root(tree_root, key, path,
1457			      &root->root_item, &root->root_key);
1458	if (ret) {
1459		if (ret > 0)
1460			ret = -ENOENT;
1461		goto fail;
1462	}
1463
1464	generation = btrfs_root_generation(&root->root_item);
1465	level = btrfs_root_level(&root->root_item);
1466	check.level = level;
1467	check.transid = generation;
1468	check.owner_root = key->objectid;
1469	root->node = read_tree_block(fs_info, btrfs_root_bytenr(&root->root_item),
1470				     &check);
1471	if (IS_ERR(root->node)) {
1472		ret = PTR_ERR(root->node);
1473		root->node = NULL;
1474		goto fail;
1475	}
1476	if (!btrfs_buffer_uptodate(root->node, generation, 0)) {
1477		ret = -EIO;
1478		goto fail;
1479	}
1480
1481	/*
1482	 * For real fs, and not log/reloc trees, root owner must
1483	 * match its root node owner
1484	 */
1485	if (!test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state) &&
1486	    root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID &&
1487	    root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID &&
1488	    root->root_key.objectid != btrfs_header_owner(root->node)) {
1489		btrfs_crit(fs_info,
1490"root=%llu block=%llu, tree root owner mismatch, have %llu expect %llu",
1491			   root->root_key.objectid, root->node->start,
1492			   btrfs_header_owner(root->node),
1493			   root->root_key.objectid);
1494		ret = -EUCLEAN;
1495		goto fail;
1496	}
1497	root->commit_root = btrfs_root_node(root);
 
 
1498	return root;
1499fail:
1500	btrfs_put_root(root);
1501	return ERR_PTR(ret);
 
 
 
1502}
1503
1504struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
1505					struct btrfs_key *key)
1506{
1507	struct btrfs_root *root;
1508	struct btrfs_path *path;
1509
1510	path = btrfs_alloc_path();
1511	if (!path)
1512		return ERR_PTR(-ENOMEM);
1513	root = read_tree_root_path(tree_root, path, key);
1514	btrfs_free_path(path);
 
 
 
1515
1516	return root;
1517}
1518
1519/*
1520 * Initialize subvolume root in-memory structure
1521 *
1522 * @anon_dev:	anonymous device to attach to the root, if zero, allocate new
1523 */
1524static int btrfs_init_fs_root(struct btrfs_root *root, dev_t anon_dev)
1525{
1526	int ret;
1527	unsigned int nofs_flag;
1528
1529	/*
1530	 * We might be called under a transaction (e.g. indirect backref
1531	 * resolution) which could deadlock if it triggers memory reclaim
1532	 */
1533	nofs_flag = memalloc_nofs_save();
1534	ret = btrfs_drew_lock_init(&root->snapshot_lock);
1535	memalloc_nofs_restore(nofs_flag);
1536	if (ret)
1537		goto fail;
 
1538
1539	if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID &&
1540	    !btrfs_is_data_reloc_root(root)) {
1541		set_bit(BTRFS_ROOT_SHAREABLE, &root->state);
1542		btrfs_check_and_init_root_item(&root->root_item);
1543	}
 
 
 
 
 
1544
1545	/*
1546	 * Don't assign anonymous block device to roots that are not exposed to
1547	 * userspace, the id pool is limited to 1M
1548	 */
1549	if (is_fstree(root->root_key.objectid) &&
1550	    btrfs_root_refs(&root->root_item) > 0) {
1551		if (!anon_dev) {
1552			ret = get_anon_bdev(&root->anon_dev);
1553			if (ret)
1554				goto fail;
1555		} else {
1556			root->anon_dev = anon_dev;
1557		}
1558	}
1559
1560	mutex_lock(&root->objectid_mutex);
1561	ret = btrfs_init_root_free_objectid(root);
 
1562	if (ret) {
1563		mutex_unlock(&root->objectid_mutex);
1564		goto fail;
1565	}
1566
1567	ASSERT(root->free_objectid <= BTRFS_LAST_FREE_OBJECTID);
1568
1569	mutex_unlock(&root->objectid_mutex);
1570
1571	return 0;
1572fail:
1573	/* The caller is responsible to call btrfs_free_fs_root */
1574	return ret;
1575}
1576
1577static struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
1578					       u64 root_id)
1579{
1580	struct btrfs_root *root;
1581
1582	spin_lock(&fs_info->fs_roots_radix_lock);
1583	root = radix_tree_lookup(&fs_info->fs_roots_radix,
1584				 (unsigned long)root_id);
1585	if (root)
1586		root = btrfs_grab_root(root);
1587	spin_unlock(&fs_info->fs_roots_radix_lock);
1588	return root;
1589}
1590
1591static struct btrfs_root *btrfs_get_global_root(struct btrfs_fs_info *fs_info,
1592						u64 objectid)
1593{
1594	struct btrfs_key key = {
1595		.objectid = objectid,
1596		.type = BTRFS_ROOT_ITEM_KEY,
1597		.offset = 0,
1598	};
1599
1600	if (objectid == BTRFS_ROOT_TREE_OBJECTID)
1601		return btrfs_grab_root(fs_info->tree_root);
1602	if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
1603		return btrfs_grab_root(btrfs_global_root(fs_info, &key));
1604	if (objectid == BTRFS_CHUNK_TREE_OBJECTID)
1605		return btrfs_grab_root(fs_info->chunk_root);
1606	if (objectid == BTRFS_DEV_TREE_OBJECTID)
1607		return btrfs_grab_root(fs_info->dev_root);
1608	if (objectid == BTRFS_CSUM_TREE_OBJECTID)
1609		return btrfs_grab_root(btrfs_global_root(fs_info, &key));
1610	if (objectid == BTRFS_QUOTA_TREE_OBJECTID)
1611		return btrfs_grab_root(fs_info->quota_root) ?
1612			fs_info->quota_root : ERR_PTR(-ENOENT);
1613	if (objectid == BTRFS_UUID_TREE_OBJECTID)
1614		return btrfs_grab_root(fs_info->uuid_root) ?
1615			fs_info->uuid_root : ERR_PTR(-ENOENT);
1616	if (objectid == BTRFS_BLOCK_GROUP_TREE_OBJECTID)
1617		return btrfs_grab_root(fs_info->block_group_root) ?
1618			fs_info->block_group_root : ERR_PTR(-ENOENT);
1619	if (objectid == BTRFS_FREE_SPACE_TREE_OBJECTID) {
1620		struct btrfs_root *root = btrfs_global_root(fs_info, &key);
1621
1622		return btrfs_grab_root(root) ? root : ERR_PTR(-ENOENT);
1623	}
1624	return NULL;
1625}
1626
1627int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
1628			 struct btrfs_root *root)
1629{
1630	int ret;
1631
1632	ret = radix_tree_preload(GFP_NOFS);
1633	if (ret)
1634		return ret;
1635
1636	spin_lock(&fs_info->fs_roots_radix_lock);
1637	ret = radix_tree_insert(&fs_info->fs_roots_radix,
1638				(unsigned long)root->root_key.objectid,
1639				root);
1640	if (ret == 0) {
1641		btrfs_grab_root(root);
1642		set_bit(BTRFS_ROOT_IN_RADIX, &root->state);
1643	}
1644	spin_unlock(&fs_info->fs_roots_radix_lock);
1645	radix_tree_preload_end();
1646
1647	return ret;
1648}
1649
1650void btrfs_check_leaked_roots(struct btrfs_fs_info *fs_info)
1651{
1652#ifdef CONFIG_BTRFS_DEBUG
1653	struct btrfs_root *root;
1654
1655	while (!list_empty(&fs_info->allocated_roots)) {
1656		char buf[BTRFS_ROOT_NAME_BUF_LEN];
1657
1658		root = list_first_entry(&fs_info->allocated_roots,
1659					struct btrfs_root, leak_list);
1660		btrfs_err(fs_info, "leaked root %s refcount %d",
1661			  btrfs_root_name(&root->root_key, buf),
1662			  refcount_read(&root->refs));
1663		while (refcount_read(&root->refs) > 1)
1664			btrfs_put_root(root);
1665		btrfs_put_root(root);
1666	}
1667#endif
1668}
1669
1670static void free_global_roots(struct btrfs_fs_info *fs_info)
1671{
1672	struct btrfs_root *root;
1673	struct rb_node *node;
1674
1675	while ((node = rb_first_postorder(&fs_info->global_root_tree)) != NULL) {
1676		root = rb_entry(node, struct btrfs_root, rb_node);
1677		rb_erase(&root->rb_node, &fs_info->global_root_tree);
1678		btrfs_put_root(root);
1679	}
1680}
1681
1682void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
1683{
1684	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
1685	percpu_counter_destroy(&fs_info->delalloc_bytes);
1686	percpu_counter_destroy(&fs_info->ordered_bytes);
1687	percpu_counter_destroy(&fs_info->dev_replace.bio_counter);
1688	btrfs_free_csum_hash(fs_info);
1689	btrfs_free_stripe_hash_table(fs_info);
1690	btrfs_free_ref_cache(fs_info);
1691	kfree(fs_info->balance_ctl);
1692	kfree(fs_info->delayed_root);
1693	free_global_roots(fs_info);
1694	btrfs_put_root(fs_info->tree_root);
1695	btrfs_put_root(fs_info->chunk_root);
1696	btrfs_put_root(fs_info->dev_root);
1697	btrfs_put_root(fs_info->quota_root);
1698	btrfs_put_root(fs_info->uuid_root);
1699	btrfs_put_root(fs_info->fs_root);
1700	btrfs_put_root(fs_info->data_reloc_root);
1701	btrfs_put_root(fs_info->block_group_root);
1702	btrfs_check_leaked_roots(fs_info);
1703	btrfs_extent_buffer_leak_debug_check(fs_info);
1704	kfree(fs_info->super_copy);
1705	kfree(fs_info->super_for_commit);
1706	kfree(fs_info->subpage_info);
1707	kvfree(fs_info);
1708}
1709
1710
1711/*
1712 * Get an in-memory reference of a root structure.
1713 *
1714 * For essential trees like root/extent tree, we grab it from fs_info directly.
1715 * For subvolume trees, we check the cached filesystem roots first. If not
1716 * found, then read it from disk and add it to cached fs roots.
1717 *
1718 * Caller should release the root by calling btrfs_put_root() after the usage.
1719 *
1720 * NOTE: Reloc and log trees can't be read by this function as they share the
1721 *	 same root objectid.
1722 *
1723 * @objectid:	root id
1724 * @anon_dev:	preallocated anonymous block device number for new roots,
1725 * 		pass 0 for new allocation.
1726 * @check_ref:	whether to check root item references, If true, return -ENOENT
1727 *		for orphan roots
1728 */
1729static struct btrfs_root *btrfs_get_root_ref(struct btrfs_fs_info *fs_info,
1730					     u64 objectid, dev_t anon_dev,
1731					     bool check_ref)
1732{
1733	struct btrfs_root *root;
1734	struct btrfs_path *path;
1735	struct btrfs_key key;
1736	int ret;
1737
1738	root = btrfs_get_global_root(fs_info, objectid);
1739	if (root)
1740		return root;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1741again:
1742	root = btrfs_lookup_fs_root(fs_info, objectid);
1743	if (root) {
1744		/* Shouldn't get preallocated anon_dev for cached roots */
1745		ASSERT(!anon_dev);
1746		if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1747			btrfs_put_root(root);
1748			return ERR_PTR(-ENOENT);
1749		}
1750		return root;
1751	}
1752
1753	key.objectid = objectid;
1754	key.type = BTRFS_ROOT_ITEM_KEY;
1755	key.offset = (u64)-1;
1756	root = btrfs_read_tree_root(fs_info->tree_root, &key);
1757	if (IS_ERR(root))
1758		return root;
1759
1760	if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1761		ret = -ENOENT;
1762		goto fail;
1763	}
1764
1765	ret = btrfs_init_fs_root(root, anon_dev);
1766	if (ret)
1767		goto fail;
1768
1769	path = btrfs_alloc_path();
1770	if (!path) {
1771		ret = -ENOMEM;
1772		goto fail;
1773	}
1774	key.objectid = BTRFS_ORPHAN_OBJECTID;
1775	key.type = BTRFS_ORPHAN_ITEM_KEY;
1776	key.offset = objectid;
1777
1778	ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
1779	btrfs_free_path(path);
1780	if (ret < 0)
1781		goto fail;
1782	if (ret == 0)
1783		set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state);
1784
1785	ret = btrfs_insert_fs_root(fs_info, root);
1786	if (ret) {
1787		if (ret == -EEXIST) {
1788			btrfs_put_root(root);
1789			goto again;
1790		}
1791		goto fail;
1792	}
1793	return root;
1794fail:
1795	/*
1796	 * If our caller provided us an anonymous device, then it's his
1797	 * responsibility to free it in case we fail. So we have to set our
1798	 * root's anon_dev to 0 to avoid a double free, once by btrfs_put_root()
1799	 * and once again by our caller.
1800	 */
1801	if (anon_dev)
1802		root->anon_dev = 0;
1803	btrfs_put_root(root);
1804	return ERR_PTR(ret);
1805}
1806
1807/*
1808 * Get in-memory reference of a root structure
1809 *
1810 * @objectid:	tree objectid
1811 * @check_ref:	if set, verify that the tree exists and the item has at least
1812 *		one reference
1813 */
1814struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
1815				     u64 objectid, bool check_ref)
1816{
1817	return btrfs_get_root_ref(fs_info, objectid, 0, check_ref);
1818}
 
 
1819
1820/*
1821 * Get in-memory reference of a root structure, created as new, optionally pass
1822 * the anonymous block device id
1823 *
1824 * @objectid:	tree objectid
1825 * @anon_dev:	if zero, allocate a new anonymous block device or use the
1826 *		parameter value
1827 */
1828struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
1829					 u64 objectid, dev_t anon_dev)
1830{
1831	return btrfs_get_root_ref(fs_info, objectid, anon_dev, true);
1832}
1833
1834/*
1835 * btrfs_get_fs_root_commit_root - return a root for the given objectid
1836 * @fs_info:	the fs_info
1837 * @objectid:	the objectid we need to lookup
1838 *
1839 * This is exclusively used for backref walking, and exists specifically because
1840 * of how qgroups does lookups.  Qgroups will do a backref lookup at delayed ref
1841 * creation time, which means we may have to read the tree_root in order to look
1842 * up a fs root that is not in memory.  If the root is not in memory we will
1843 * read the tree root commit root and look up the fs root from there.  This is a
1844 * temporary root, it will not be inserted into the radix tree as it doesn't
1845 * have the most uptodate information, it'll simply be discarded once the
1846 * backref code is finished using the root.
1847 */
1848struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
1849						 struct btrfs_path *path,
1850						 u64 objectid)
1851{
1852	struct btrfs_root *root;
1853	struct btrfs_key key;
1854
1855	ASSERT(path->search_commit_root && path->skip_locking);
1856
1857	/*
1858	 * This can return -ENOENT if we ask for a root that doesn't exist, but
1859	 * since this is called via the backref walking code we won't be looking
1860	 * up a root that doesn't exist, unless there's corruption.  So if root
1861	 * != NULL just return it.
1862	 */
1863	root = btrfs_get_global_root(fs_info, objectid);
1864	if (root)
1865		return root;
1866
1867	root = btrfs_lookup_fs_root(fs_info, objectid);
1868	if (root)
1869		return root;
1870
1871	key.objectid = objectid;
1872	key.type = BTRFS_ROOT_ITEM_KEY;
1873	key.offset = (u64)-1;
1874	root = read_tree_root_path(fs_info->tree_root, path, &key);
1875	btrfs_release_path(path);
1876
1877	return root;
 
 
 
 
1878}
1879
1880static int cleaner_kthread(void *arg)
1881{
1882	struct btrfs_fs_info *fs_info = arg;
 
1883	int again;
1884
1885	while (1) {
1886		again = 0;
1887
1888		set_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1889
1890		/* Make the cleaner go to sleep early. */
1891		if (btrfs_need_cleaner_sleep(fs_info))
1892			goto sleep;
1893
1894		/*
1895		 * Do not do anything if we might cause open_ctree() to block
1896		 * before we have finished mounting the filesystem.
1897		 */
1898		if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags))
1899			goto sleep;
1900
1901		if (!mutex_trylock(&fs_info->cleaner_mutex))
1902			goto sleep;
1903
1904		/*
1905		 * Avoid the problem that we change the status of the fs
1906		 * during the above check and trylock.
1907		 */
1908		if (btrfs_need_cleaner_sleep(fs_info)) {
1909			mutex_unlock(&fs_info->cleaner_mutex);
1910			goto sleep;
1911		}
1912
1913		btrfs_run_delayed_iputs(fs_info);
1914
1915		again = btrfs_clean_one_deleted_snapshot(fs_info);
1916		mutex_unlock(&fs_info->cleaner_mutex);
1917
1918		/*
1919		 * The defragger has dealt with the R/O remount and umount,
1920		 * needn't do anything special here.
1921		 */
1922		btrfs_run_defrag_inodes(fs_info);
1923
1924		/*
1925		 * Acquires fs_info->reclaim_bgs_lock to avoid racing
1926		 * with relocation (btrfs_relocate_chunk) and relocation
1927		 * acquires fs_info->cleaner_mutex (btrfs_relocate_block_group)
1928		 * after acquiring fs_info->reclaim_bgs_lock. So we
1929		 * can't hold, nor need to, fs_info->cleaner_mutex when deleting
1930		 * unused block groups.
1931		 */
1932		btrfs_delete_unused_bgs(fs_info);
1933
1934		/*
1935		 * Reclaim block groups in the reclaim_bgs list after we deleted
1936		 * all unused block_groups. This possibly gives us some more free
1937		 * space.
1938		 */
1939		btrfs_reclaim_bgs(fs_info);
1940sleep:
1941		clear_and_wake_up_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1942		if (kthread_should_park())
1943			kthread_parkme();
1944		if (kthread_should_stop())
1945			return 0;
1946		if (!again) {
1947			set_current_state(TASK_INTERRUPTIBLE);
1948			schedule();
1949			__set_current_state(TASK_RUNNING);
1950		}
1951	}
1952}
1953
1954static int transaction_kthread(void *arg)
1955{
1956	struct btrfs_root *root = arg;
1957	struct btrfs_fs_info *fs_info = root->fs_info;
1958	struct btrfs_trans_handle *trans;
1959	struct btrfs_transaction *cur;
1960	u64 transid;
1961	time64_t delta;
1962	unsigned long delay;
1963	bool cannot_commit;
1964
1965	do {
1966		cannot_commit = false;
1967		delay = msecs_to_jiffies(fs_info->commit_interval * 1000);
1968		mutex_lock(&fs_info->transaction_kthread_mutex);
1969
1970		spin_lock(&fs_info->trans_lock);
1971		cur = fs_info->running_transaction;
1972		if (!cur) {
1973			spin_unlock(&fs_info->trans_lock);
1974			goto sleep;
1975		}
1976
1977		delta = ktime_get_seconds() - cur->start_time;
1978		if (!test_and_clear_bit(BTRFS_FS_COMMIT_TRANS, &fs_info->flags) &&
1979		    cur->state < TRANS_STATE_COMMIT_START &&
1980		    delta < fs_info->commit_interval) {
 
1981			spin_unlock(&fs_info->trans_lock);
1982			delay -= msecs_to_jiffies((delta - 1) * 1000);
1983			delay = min(delay,
1984				    msecs_to_jiffies(fs_info->commit_interval * 1000));
1985			goto sleep;
1986		}
1987		transid = cur->transid;
1988		spin_unlock(&fs_info->trans_lock);
1989
1990		/* If the file system is aborted, this will always fail. */
1991		trans = btrfs_attach_transaction(root);
1992		if (IS_ERR(trans)) {
1993			if (PTR_ERR(trans) != -ENOENT)
1994				cannot_commit = true;
1995			goto sleep;
1996		}
1997		if (transid == trans->transid) {
1998			btrfs_commit_transaction(trans);
1999		} else {
2000			btrfs_end_transaction(trans);
2001		}
2002sleep:
2003		wake_up_process(fs_info->cleaner_kthread);
2004		mutex_unlock(&fs_info->transaction_kthread_mutex);
2005
2006		if (BTRFS_FS_ERROR(fs_info))
 
2007			btrfs_cleanup_transaction(fs_info);
2008		if (!kthread_should_stop() &&
2009				(!btrfs_transaction_blocked(fs_info) ||
2010				 cannot_commit))
2011			schedule_timeout_interruptible(delay);
2012	} while (!kthread_should_stop());
2013	return 0;
2014}
2015
2016/*
2017 * This will find the highest generation in the array of root backups.  The
2018 * index of the highest array is returned, or -EINVAL if we can't find
2019 * anything.
2020 *
2021 * We check to make sure the array is valid by comparing the
2022 * generation of the latest  root in the array with the generation
2023 * in the super block.  If they don't match we pitch it.
2024 */
2025static int find_newest_super_backup(struct btrfs_fs_info *info)
2026{
2027	const u64 newest_gen = btrfs_super_generation(info->super_copy);
2028	u64 cur;
 
2029	struct btrfs_root_backup *root_backup;
2030	int i;
2031
2032	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
2033		root_backup = info->super_copy->super_roots + i;
2034		cur = btrfs_backup_tree_root_gen(root_backup);
2035		if (cur == newest_gen)
2036			return i;
2037	}
2038
2039	return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2040}
2041
2042/*
2043 * copy all the root pointers into the super backup array.
2044 * this will bump the backup pointer by one when it is
2045 * done
2046 */
2047static void backup_super_roots(struct btrfs_fs_info *info)
2048{
2049	const int next_backup = info->backup_root_index;
2050	struct btrfs_root_backup *root_backup;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2051
2052	root_backup = info->super_for_commit->super_roots + next_backup;
2053
2054	/*
2055	 * make sure all of our padding and empty slots get zero filled
2056	 * regardless of which ones we use today
2057	 */
2058	memset(root_backup, 0, sizeof(*root_backup));
2059
2060	info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
2061
2062	btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
2063	btrfs_set_backup_tree_root_gen(root_backup,
2064			       btrfs_header_generation(info->tree_root->node));
2065
2066	btrfs_set_backup_tree_root_level(root_backup,
2067			       btrfs_header_level(info->tree_root->node));
2068
2069	btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
2070	btrfs_set_backup_chunk_root_gen(root_backup,
2071			       btrfs_header_generation(info->chunk_root->node));
2072	btrfs_set_backup_chunk_root_level(root_backup,
2073			       btrfs_header_level(info->chunk_root->node));
2074
2075	if (!btrfs_fs_compat_ro(info, BLOCK_GROUP_TREE)) {
2076		struct btrfs_root *extent_root = btrfs_extent_root(info, 0);
2077		struct btrfs_root *csum_root = btrfs_csum_root(info, 0);
2078
2079		btrfs_set_backup_extent_root(root_backup,
2080					     extent_root->node->start);
2081		btrfs_set_backup_extent_root_gen(root_backup,
2082				btrfs_header_generation(extent_root->node));
2083		btrfs_set_backup_extent_root_level(root_backup,
2084					btrfs_header_level(extent_root->node));
2085
2086		btrfs_set_backup_csum_root(root_backup, csum_root->node->start);
2087		btrfs_set_backup_csum_root_gen(root_backup,
2088					       btrfs_header_generation(csum_root->node));
2089		btrfs_set_backup_csum_root_level(root_backup,
2090						 btrfs_header_level(csum_root->node));
2091	}
2092
2093	/*
2094	 * we might commit during log recovery, which happens before we set
2095	 * the fs_root.  Make sure it is valid before we fill it in.
2096	 */
2097	if (info->fs_root && info->fs_root->node) {
2098		btrfs_set_backup_fs_root(root_backup,
2099					 info->fs_root->node->start);
2100		btrfs_set_backup_fs_root_gen(root_backup,
2101			       btrfs_header_generation(info->fs_root->node));
2102		btrfs_set_backup_fs_root_level(root_backup,
2103			       btrfs_header_level(info->fs_root->node));
2104	}
2105
2106	btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
2107	btrfs_set_backup_dev_root_gen(root_backup,
2108			       btrfs_header_generation(info->dev_root->node));
2109	btrfs_set_backup_dev_root_level(root_backup,
2110				       btrfs_header_level(info->dev_root->node));
2111
 
 
 
 
 
 
2112	btrfs_set_backup_total_bytes(root_backup,
2113			     btrfs_super_total_bytes(info->super_copy));
2114	btrfs_set_backup_bytes_used(root_backup,
2115			     btrfs_super_bytes_used(info->super_copy));
2116	btrfs_set_backup_num_devices(root_backup,
2117			     btrfs_super_num_devices(info->super_copy));
2118
2119	/*
2120	 * if we don't copy this out to the super_copy, it won't get remembered
2121	 * for the next commit
2122	 */
2123	memcpy(&info->super_copy->super_roots,
2124	       &info->super_for_commit->super_roots,
2125	       sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
2126}
2127
2128/*
2129 * read_backup_root - Reads a backup root based on the passed priority. Prio 0
2130 * is the newest, prio 1/2/3 are 2nd newest/3rd newest/4th (oldest) backup roots
 
 
2131 *
2132 * fs_info - filesystem whose backup roots need to be read
2133 * priority - priority of backup root required
2134 *
2135 * Returns backup root index on success and -EINVAL otherwise.
2136 */
2137static int read_backup_root(struct btrfs_fs_info *fs_info, u8 priority)
 
 
2138{
2139	int backup_index = find_newest_super_backup(fs_info);
2140	struct btrfs_super_block *super = fs_info->super_copy;
2141	struct btrfs_root_backup *root_backup;
 
2142
2143	if (priority < BTRFS_NUM_BACKUP_ROOTS && backup_index >= 0) {
2144		if (priority == 0)
2145			return backup_index;
2146
2147		backup_index = backup_index + BTRFS_NUM_BACKUP_ROOTS - priority;
2148		backup_index %= BTRFS_NUM_BACKUP_ROOTS;
 
 
 
 
 
 
 
2149	} else {
2150		return -EINVAL;
 
 
 
 
2151	}
2152
2153	root_backup = super->super_roots + backup_index;
2154
2155	btrfs_set_super_generation(super,
2156				   btrfs_backup_tree_root_gen(root_backup));
2157	btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
2158	btrfs_set_super_root_level(super,
2159				   btrfs_backup_tree_root_level(root_backup));
2160	btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
2161
2162	/*
2163	 * Fixme: the total bytes and num_devices need to match or we should
2164	 * need a fsck
2165	 */
2166	btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
2167	btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
2168
2169	return backup_index;
2170}
2171
2172/* helper to cleanup workers */
2173static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
2174{
2175	btrfs_destroy_workqueue(fs_info->fixup_workers);
2176	btrfs_destroy_workqueue(fs_info->delalloc_workers);
2177	btrfs_destroy_workqueue(fs_info->hipri_workers);
2178	btrfs_destroy_workqueue(fs_info->workers);
2179	if (fs_info->endio_workers)
2180		destroy_workqueue(fs_info->endio_workers);
2181	if (fs_info->rmw_workers)
2182		destroy_workqueue(fs_info->rmw_workers);
2183	if (fs_info->compressed_write_workers)
2184		destroy_workqueue(fs_info->compressed_write_workers);
2185	btrfs_destroy_workqueue(fs_info->endio_write_workers);
2186	btrfs_destroy_workqueue(fs_info->endio_freespace_worker);
 
2187	btrfs_destroy_workqueue(fs_info->delayed_workers);
2188	btrfs_destroy_workqueue(fs_info->caching_workers);
 
2189	btrfs_destroy_workqueue(fs_info->flush_workers);
2190	btrfs_destroy_workqueue(fs_info->qgroup_rescan_workers);
2191	if (fs_info->discard_ctl.discard_workers)
2192		destroy_workqueue(fs_info->discard_ctl.discard_workers);
2193	/*
2194	 * Now that all other work queues are destroyed, we can safely destroy
2195	 * the queues used for metadata I/O, since tasks from those other work
2196	 * queues can do metadata I/O operations.
2197	 */
2198	if (fs_info->endio_meta_workers)
2199		destroy_workqueue(fs_info->endio_meta_workers);
2200}
2201
2202static void free_root_extent_buffers(struct btrfs_root *root)
2203{
2204	if (root) {
2205		free_extent_buffer(root->node);
2206		free_extent_buffer(root->commit_root);
2207		root->node = NULL;
2208		root->commit_root = NULL;
2209	}
2210}
2211
2212static void free_global_root_pointers(struct btrfs_fs_info *fs_info)
2213{
2214	struct btrfs_root *root, *tmp;
2215
2216	rbtree_postorder_for_each_entry_safe(root, tmp,
2217					     &fs_info->global_root_tree,
2218					     rb_node)
2219		free_root_extent_buffers(root);
2220}
2221
2222/* helper to cleanup tree roots */
2223static void free_root_pointers(struct btrfs_fs_info *info, bool free_chunk_root)
2224{
2225	free_root_extent_buffers(info->tree_root);
2226
2227	free_global_root_pointers(info);
2228	free_root_extent_buffers(info->dev_root);
 
 
2229	free_root_extent_buffers(info->quota_root);
2230	free_root_extent_buffers(info->uuid_root);
2231	free_root_extent_buffers(info->fs_root);
2232	free_root_extent_buffers(info->data_reloc_root);
2233	free_root_extent_buffers(info->block_group_root);
2234	if (free_chunk_root)
2235		free_root_extent_buffers(info->chunk_root);
2236}
2237
2238void btrfs_put_root(struct btrfs_root *root)
2239{
2240	if (!root)
2241		return;
2242
2243	if (refcount_dec_and_test(&root->refs)) {
2244		WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
2245		WARN_ON(test_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state));
2246		if (root->anon_dev)
2247			free_anon_bdev(root->anon_dev);
2248		btrfs_drew_lock_destroy(&root->snapshot_lock);
2249		free_root_extent_buffers(root);
2250#ifdef CONFIG_BTRFS_DEBUG
2251		spin_lock(&root->fs_info->fs_roots_radix_lock);
2252		list_del_init(&root->leak_list);
2253		spin_unlock(&root->fs_info->fs_roots_radix_lock);
2254#endif
2255		kfree(root);
2256	}
2257}
2258
2259void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info)
2260{
2261	int ret;
2262	struct btrfs_root *gang[8];
2263	int i;
2264
2265	while (!list_empty(&fs_info->dead_roots)) {
2266		gang[0] = list_entry(fs_info->dead_roots.next,
2267				     struct btrfs_root, root_list);
2268		list_del(&gang[0]->root_list);
2269
2270		if (test_bit(BTRFS_ROOT_IN_RADIX, &gang[0]->state))
2271			btrfs_drop_and_free_fs_root(fs_info, gang[0]);
2272		btrfs_put_root(gang[0]);
 
 
 
 
2273	}
2274
2275	while (1) {
2276		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2277					     (void **)gang, 0,
2278					     ARRAY_SIZE(gang));
2279		if (!ret)
2280			break;
2281		for (i = 0; i < ret; i++)
2282			btrfs_drop_and_free_fs_root(fs_info, gang[i]);
2283	}
 
 
 
 
 
2284}
2285
2286static void btrfs_init_scrub(struct btrfs_fs_info *fs_info)
2287{
2288	mutex_init(&fs_info->scrub_lock);
2289	atomic_set(&fs_info->scrubs_running, 0);
2290	atomic_set(&fs_info->scrub_pause_req, 0);
2291	atomic_set(&fs_info->scrubs_paused, 0);
2292	atomic_set(&fs_info->scrub_cancel_req, 0);
2293	init_waitqueue_head(&fs_info->scrub_pause_wait);
2294	refcount_set(&fs_info->scrub_workers_refcnt, 0);
2295}
2296
2297static void btrfs_init_balance(struct btrfs_fs_info *fs_info)
2298{
2299	spin_lock_init(&fs_info->balance_lock);
2300	mutex_init(&fs_info->balance_mutex);
2301	atomic_set(&fs_info->balance_pause_req, 0);
2302	atomic_set(&fs_info->balance_cancel_req, 0);
2303	fs_info->balance_ctl = NULL;
2304	init_waitqueue_head(&fs_info->balance_wait_q);
2305	atomic_set(&fs_info->reloc_cancel_req, 0);
2306}
2307
2308static void btrfs_init_btree_inode(struct btrfs_fs_info *fs_info)
2309{
2310	struct inode *inode = fs_info->btree_inode;
2311	unsigned long hash = btrfs_inode_hash(BTRFS_BTREE_INODE_OBJECTID,
2312					      fs_info->tree_root);
2313
2314	inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
2315	set_nlink(inode, 1);
2316	/*
2317	 * we set the i_size on the btree inode to the max possible int.
2318	 * the real end of the address space is determined by all of
2319	 * the devices in the system
2320	 */
2321	inode->i_size = OFFSET_MAX;
2322	inode->i_mapping->a_ops = &btree_aops;
2323
2324	RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
2325	extent_io_tree_init(fs_info, &BTRFS_I(inode)->io_tree,
2326			    IO_TREE_BTREE_INODE_IO);
 
2327	extent_map_tree_init(&BTRFS_I(inode)->extent_tree);
2328
2329	BTRFS_I(inode)->root = btrfs_grab_root(fs_info->tree_root);
2330	BTRFS_I(inode)->location.objectid = BTRFS_BTREE_INODE_OBJECTID;
2331	BTRFS_I(inode)->location.type = 0;
2332	BTRFS_I(inode)->location.offset = 0;
2333	set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
2334	__insert_inode_hash(inode, hash);
2335}
2336
2337static void btrfs_init_dev_replace_locks(struct btrfs_fs_info *fs_info)
2338{
2339	mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount);
2340	init_rwsem(&fs_info->dev_replace.rwsem);
2341	init_waitqueue_head(&fs_info->dev_replace.replace_wait);
2342}
2343
2344static void btrfs_init_qgroup(struct btrfs_fs_info *fs_info)
2345{
2346	spin_lock_init(&fs_info->qgroup_lock);
2347	mutex_init(&fs_info->qgroup_ioctl_lock);
2348	fs_info->qgroup_tree = RB_ROOT;
2349	INIT_LIST_HEAD(&fs_info->dirty_qgroups);
2350	fs_info->qgroup_seq = 1;
2351	fs_info->qgroup_ulist = NULL;
2352	fs_info->qgroup_rescan_running = false;
2353	fs_info->qgroup_drop_subtree_thres = BTRFS_MAX_LEVEL;
2354	mutex_init(&fs_info->qgroup_rescan_lock);
2355}
2356
2357static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info)
 
2358{
2359	u32 max_active = fs_info->thread_pool_size;
2360	unsigned int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND;
2361
2362	fs_info->workers =
2363		btrfs_alloc_workqueue(fs_info, "worker", flags, max_active, 16);
2364	fs_info->hipri_workers =
2365		btrfs_alloc_workqueue(fs_info, "worker-high",
2366				      flags | WQ_HIGHPRI, max_active, 16);
2367
2368	fs_info->delalloc_workers =
2369		btrfs_alloc_workqueue(fs_info, "delalloc",
2370				      flags, max_active, 2);
2371
2372	fs_info->flush_workers =
2373		btrfs_alloc_workqueue(fs_info, "flush_delalloc",
2374				      flags, max_active, 0);
2375
2376	fs_info->caching_workers =
2377		btrfs_alloc_workqueue(fs_info, "cache", flags, max_active, 0);
2378
 
 
 
 
 
 
 
 
 
 
2379	fs_info->fixup_workers =
2380		btrfs_alloc_workqueue(fs_info, "fixup", flags, 1, 0);
2381
 
 
 
 
2382	fs_info->endio_workers =
2383		alloc_workqueue("btrfs-endio", flags, max_active);
2384	fs_info->endio_meta_workers =
2385		alloc_workqueue("btrfs-endio-meta", flags, max_active);
2386	fs_info->rmw_workers = alloc_workqueue("btrfs-rmw", flags, max_active);
 
 
 
 
 
 
 
 
 
 
2387	fs_info->endio_write_workers =
2388		btrfs_alloc_workqueue(fs_info, "endio-write", flags,
2389				      max_active, 2);
2390	fs_info->compressed_write_workers =
2391		alloc_workqueue("btrfs-compressed-write", flags, max_active);
2392	fs_info->endio_freespace_worker =
2393		btrfs_alloc_workqueue(fs_info, "freespace-write", flags,
2394				      max_active, 0);
2395	fs_info->delayed_workers =
2396		btrfs_alloc_workqueue(fs_info, "delayed-meta", flags,
2397				      max_active, 0);
 
 
 
2398	fs_info->qgroup_rescan_workers =
2399		btrfs_alloc_workqueue(fs_info, "qgroup-rescan", flags, 1, 0);
2400	fs_info->discard_ctl.discard_workers =
2401		alloc_workqueue("btrfs_discard", WQ_UNBOUND | WQ_FREEZABLE, 1);
2402
2403	if (!(fs_info->workers && fs_info->hipri_workers &&
2404	      fs_info->delalloc_workers && fs_info->flush_workers &&
2405	      fs_info->endio_workers && fs_info->endio_meta_workers &&
2406	      fs_info->compressed_write_workers &&
2407	      fs_info->endio_write_workers &&
 
2408	      fs_info->endio_freespace_worker && fs_info->rmw_workers &&
2409	      fs_info->caching_workers && fs_info->fixup_workers &&
2410	      fs_info->delayed_workers && fs_info->qgroup_rescan_workers &&
2411	      fs_info->discard_ctl.discard_workers)) {
2412		return -ENOMEM;
2413	}
2414
2415	return 0;
2416}
2417
2418static int btrfs_init_csum_hash(struct btrfs_fs_info *fs_info, u16 csum_type)
2419{
2420	struct crypto_shash *csum_shash;
2421	const char *csum_driver = btrfs_super_csum_driver(csum_type);
2422
2423	csum_shash = crypto_alloc_shash(csum_driver, 0, 0);
2424
2425	if (IS_ERR(csum_shash)) {
2426		btrfs_err(fs_info, "error allocating %s hash for checksum",
2427			  csum_driver);
2428		return PTR_ERR(csum_shash);
2429	}
2430
2431	fs_info->csum_shash = csum_shash;
2432
2433	btrfs_info(fs_info, "using %s (%s) checksum algorithm",
2434			btrfs_super_csum_name(csum_type),
2435			crypto_shash_driver_name(csum_shash));
2436	return 0;
2437}
2438
 
 
 
 
 
2439static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
2440			    struct btrfs_fs_devices *fs_devices)
2441{
2442	int ret;
2443	struct btrfs_tree_parent_check check = { 0 };
2444	struct btrfs_root *log_tree_root;
2445	struct btrfs_super_block *disk_super = fs_info->super_copy;
2446	u64 bytenr = btrfs_super_log_root(disk_super);
2447	int level = btrfs_super_log_root_level(disk_super);
2448
2449	if (fs_devices->rw_devices == 0) {
2450		btrfs_warn(fs_info, "log replay required on RO media");
2451		return -EIO;
2452	}
2453
2454	log_tree_root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID,
2455					 GFP_KERNEL);
2456	if (!log_tree_root)
2457		return -ENOMEM;
2458
2459	check.level = level;
2460	check.transid = fs_info->generation + 1;
2461	check.owner_root = BTRFS_TREE_LOG_OBJECTID;
2462	log_tree_root->node = read_tree_block(fs_info, bytenr, &check);
 
2463	if (IS_ERR(log_tree_root->node)) {
2464		btrfs_warn(fs_info, "failed to read log tree");
2465		ret = PTR_ERR(log_tree_root->node);
2466		log_tree_root->node = NULL;
2467		btrfs_put_root(log_tree_root);
2468		return ret;
2469	}
2470	if (!extent_buffer_uptodate(log_tree_root->node)) {
2471		btrfs_err(fs_info, "failed to read log tree");
2472		btrfs_put_root(log_tree_root);
 
2473		return -EIO;
2474	}
2475
2476	/* returns with log_tree_root freed on success */
2477	ret = btrfs_recover_log_trees(log_tree_root);
2478	if (ret) {
2479		btrfs_handle_fs_error(fs_info, ret,
2480				      "Failed to recover log tree");
2481		btrfs_put_root(log_tree_root);
 
2482		return ret;
2483	}
2484
2485	if (sb_rdonly(fs_info->sb)) {
2486		ret = btrfs_commit_super(fs_info);
2487		if (ret)
2488			return ret;
2489	}
2490
2491	return 0;
2492}
2493
2494static int load_global_roots_objectid(struct btrfs_root *tree_root,
2495				      struct btrfs_path *path, u64 objectid,
2496				      const char *name)
2497{
2498	struct btrfs_fs_info *fs_info = tree_root->fs_info;
2499	struct btrfs_root *root;
2500	u64 max_global_id = 0;
2501	int ret;
2502	struct btrfs_key key = {
2503		.objectid = objectid,
2504		.type = BTRFS_ROOT_ITEM_KEY,
2505		.offset = 0,
2506	};
2507	bool found = false;
2508
2509	/* If we have IGNOREDATACSUMS skip loading these roots. */
2510	if (objectid == BTRFS_CSUM_TREE_OBJECTID &&
2511	    btrfs_test_opt(fs_info, IGNOREDATACSUMS)) {
2512		set_bit(BTRFS_FS_STATE_NO_CSUMS, &fs_info->fs_state);
2513		return 0;
2514	}
2515
2516	while (1) {
2517		ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0);
2518		if (ret < 0)
2519			break;
2520
2521		if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
2522			ret = btrfs_next_leaf(tree_root, path);
2523			if (ret) {
2524				if (ret > 0)
2525					ret = 0;
2526				break;
2527			}
2528		}
2529		ret = 0;
2530
2531		btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
2532		if (key.objectid != objectid)
2533			break;
2534		btrfs_release_path(path);
2535
2536		/*
2537		 * Just worry about this for extent tree, it'll be the same for
2538		 * everybody.
2539		 */
2540		if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
2541			max_global_id = max(max_global_id, key.offset);
2542
2543		found = true;
2544		root = read_tree_root_path(tree_root, path, &key);
2545		if (IS_ERR(root)) {
2546			if (!btrfs_test_opt(fs_info, IGNOREBADROOTS))
2547				ret = PTR_ERR(root);
2548			break;
2549		}
2550		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2551		ret = btrfs_global_root_insert(root);
2552		if (ret) {
2553			btrfs_put_root(root);
2554			break;
2555		}
2556		key.offset++;
2557	}
2558	btrfs_release_path(path);
2559
2560	if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
2561		fs_info->nr_global_roots = max_global_id + 1;
2562
2563	if (!found || ret) {
2564		if (objectid == BTRFS_CSUM_TREE_OBJECTID)
2565			set_bit(BTRFS_FS_STATE_NO_CSUMS, &fs_info->fs_state);
2566
2567		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS))
2568			ret = ret ? ret : -ENOENT;
2569		else
2570			ret = 0;
2571		btrfs_err(fs_info, "failed to load root %s", name);
2572	}
2573	return ret;
2574}
2575
2576static int load_global_roots(struct btrfs_root *tree_root)
2577{
2578	struct btrfs_path *path;
2579	int ret = 0;
2580
2581	path = btrfs_alloc_path();
2582	if (!path)
2583		return -ENOMEM;
2584
2585	ret = load_global_roots_objectid(tree_root, path,
2586					 BTRFS_EXTENT_TREE_OBJECTID, "extent");
2587	if (ret)
2588		goto out;
2589	ret = load_global_roots_objectid(tree_root, path,
2590					 BTRFS_CSUM_TREE_OBJECTID, "csum");
2591	if (ret)
2592		goto out;
2593	if (!btrfs_fs_compat_ro(tree_root->fs_info, FREE_SPACE_TREE))
2594		goto out;
2595	ret = load_global_roots_objectid(tree_root, path,
2596					 BTRFS_FREE_SPACE_TREE_OBJECTID,
2597					 "free space");
2598out:
2599	btrfs_free_path(path);
2600	return ret;
2601}
2602
2603static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
2604{
2605	struct btrfs_root *tree_root = fs_info->tree_root;
2606	struct btrfs_root *root;
2607	struct btrfs_key location;
2608	int ret;
2609
2610	BUG_ON(!fs_info->tree_root);
2611
2612	ret = load_global_roots(tree_root);
2613	if (ret)
2614		return ret;
2615
2616	location.type = BTRFS_ROOT_ITEM_KEY;
2617	location.offset = 0;
2618
2619	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE)) {
2620		location.objectid = BTRFS_BLOCK_GROUP_TREE_OBJECTID;
2621		root = btrfs_read_tree_root(tree_root, &location);
2622		if (IS_ERR(root)) {
2623			if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2624				ret = PTR_ERR(root);
2625				goto out;
2626			}
2627		} else {
2628			set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2629			fs_info->block_group_root = root;
2630		}
2631	}
 
 
2632
2633	location.objectid = BTRFS_DEV_TREE_OBJECTID;
2634	root = btrfs_read_tree_root(tree_root, &location);
2635	if (IS_ERR(root)) {
2636		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2637			ret = PTR_ERR(root);
2638			goto out;
2639		}
2640	} else {
2641		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2642		fs_info->dev_root = root;
2643	}
2644	/* Initialize fs_info for all devices in any case */
2645	ret = btrfs_init_devices_late(fs_info);
2646	if (ret)
2647		goto out;
2648
2649	/*
2650	 * This tree can share blocks with some other fs tree during relocation
2651	 * and we need a proper setup by btrfs_get_fs_root
2652	 */
2653	root = btrfs_get_fs_root(tree_root->fs_info,
2654				 BTRFS_DATA_RELOC_TREE_OBJECTID, true);
2655	if (IS_ERR(root)) {
2656		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
2657			ret = PTR_ERR(root);
2658			goto out;
2659		}
2660	} else {
2661		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2662		fs_info->data_reloc_root = root;
2663	}
 
 
2664
2665	location.objectid = BTRFS_QUOTA_TREE_OBJECTID;
2666	root = btrfs_read_tree_root(tree_root, &location);
2667	if (!IS_ERR(root)) {
2668		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2669		set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
2670		fs_info->quota_root = root;
2671	}
2672
2673	location.objectid = BTRFS_UUID_TREE_OBJECTID;
2674	root = btrfs_read_tree_root(tree_root, &location);
2675	if (IS_ERR(root)) {
2676		if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
 
 
 
 
 
 
 
 
 
 
 
2677			ret = PTR_ERR(root);
2678			if (ret != -ENOENT)
2679				goto out;
2680		}
2681	} else {
2682		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2683		fs_info->uuid_root = root;
2684	}
2685
2686	return 0;
2687out:
2688	btrfs_warn(fs_info, "failed to read root (objectid=%llu): %d",
2689		   location.objectid, ret);
2690	return ret;
2691}
2692
2693/*
2694 * Real super block validation
2695 * NOTE: super csum type and incompat features will not be checked here.
2696 *
2697 * @sb:		super block to check
2698 * @mirror_num:	the super block number to check its bytenr:
2699 * 		0	the primary (1st) sb
2700 * 		1, 2	2nd and 3rd backup copy
2701 * 	       -1	skip bytenr check
2702 */
2703int btrfs_validate_super(struct btrfs_fs_info *fs_info,
2704			 struct btrfs_super_block *sb, int mirror_num)
2705{
2706	u64 nodesize = btrfs_super_nodesize(sb);
2707	u64 sectorsize = btrfs_super_sectorsize(sb);
2708	int ret = 0;
2709
2710	if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
2711		btrfs_err(fs_info, "no valid FS found");
2712		ret = -EINVAL;
2713	}
2714	if (btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP) {
2715		btrfs_err(fs_info, "unrecognized or unsupported super flag: %llu",
2716				btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);
2717		ret = -EINVAL;
2718	}
2719	if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
2720		btrfs_err(fs_info, "tree_root level too big: %d >= %d",
2721				btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
2722		ret = -EINVAL;
2723	}
2724	if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
2725		btrfs_err(fs_info, "chunk_root level too big: %d >= %d",
2726				btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
2727		ret = -EINVAL;
2728	}
2729	if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
2730		btrfs_err(fs_info, "log_root level too big: %d >= %d",
2731				btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
2732		ret = -EINVAL;
2733	}
2734
2735	/*
2736	 * Check sectorsize and nodesize first, other check will need it.
2737	 * Check all possible sectorsize(4K, 8K, 16K, 32K, 64K) here.
2738	 */
2739	if (!is_power_of_2(sectorsize) || sectorsize < 4096 ||
2740	    sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2741		btrfs_err(fs_info, "invalid sectorsize %llu", sectorsize);
2742		ret = -EINVAL;
2743	}
2744
2745	/*
2746	 * We only support at most two sectorsizes: 4K and PAGE_SIZE.
2747	 *
2748	 * We can support 16K sectorsize with 64K page size without problem,
2749	 * but such sectorsize/pagesize combination doesn't make much sense.
2750	 * 4K will be our future standard, PAGE_SIZE is supported from the very
2751	 * beginning.
2752	 */
2753	if (sectorsize > PAGE_SIZE || (sectorsize != SZ_4K && sectorsize != PAGE_SIZE)) {
2754		btrfs_err(fs_info,
2755			"sectorsize %llu not yet supported for page size %lu",
2756			sectorsize, PAGE_SIZE);
2757		ret = -EINVAL;
2758	}
2759
2760	if (!is_power_of_2(nodesize) || nodesize < sectorsize ||
2761	    nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2762		btrfs_err(fs_info, "invalid nodesize %llu", nodesize);
2763		ret = -EINVAL;
2764	}
2765	if (nodesize != le32_to_cpu(sb->__unused_leafsize)) {
2766		btrfs_err(fs_info, "invalid leafsize %u, should be %llu",
2767			  le32_to_cpu(sb->__unused_leafsize), nodesize);
2768		ret = -EINVAL;
2769	}
2770
2771	/* Root alignment check */
2772	if (!IS_ALIGNED(btrfs_super_root(sb), sectorsize)) {
2773		btrfs_warn(fs_info, "tree_root block unaligned: %llu",
2774			   btrfs_super_root(sb));
2775		ret = -EINVAL;
2776	}
2777	if (!IS_ALIGNED(btrfs_super_chunk_root(sb), sectorsize)) {
2778		btrfs_warn(fs_info, "chunk_root block unaligned: %llu",
2779			   btrfs_super_chunk_root(sb));
2780		ret = -EINVAL;
2781	}
2782	if (!IS_ALIGNED(btrfs_super_log_root(sb), sectorsize)) {
2783		btrfs_warn(fs_info, "log_root block unaligned: %llu",
2784			   btrfs_super_log_root(sb));
2785		ret = -EINVAL;
2786	}
2787
2788	if (memcmp(fs_info->fs_devices->fsid, fs_info->super_copy->fsid,
2789		   BTRFS_FSID_SIZE)) {
2790		btrfs_err(fs_info,
2791		"superblock fsid doesn't match fsid of fs_devices: %pU != %pU",
2792			fs_info->super_copy->fsid, fs_info->fs_devices->fsid);
2793		ret = -EINVAL;
2794	}
2795
2796	if (btrfs_fs_incompat(fs_info, METADATA_UUID) &&
2797	    memcmp(fs_info->fs_devices->metadata_uuid,
2798		   fs_info->super_copy->metadata_uuid, BTRFS_FSID_SIZE)) {
2799		btrfs_err(fs_info,
2800"superblock metadata_uuid doesn't match metadata uuid of fs_devices: %pU != %pU",
2801			fs_info->super_copy->metadata_uuid,
2802			fs_info->fs_devices->metadata_uuid);
2803		ret = -EINVAL;
2804	}
2805
2806	/*
2807	 * Artificial requirement for block-group-tree to force newer features
2808	 * (free-space-tree, no-holes) so the test matrix is smaller.
2809	 */
2810	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE) &&
2811	    (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID) ||
2812	     !btrfs_fs_incompat(fs_info, NO_HOLES))) {
2813		btrfs_err(fs_info,
2814		"block-group-tree feature requires fres-space-tree and no-holes");
2815		ret = -EINVAL;
2816	}
2817
2818	if (memcmp(fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid,
2819		   BTRFS_FSID_SIZE) != 0) {
2820		btrfs_err(fs_info,
2821			"dev_item UUID does not match metadata fsid: %pU != %pU",
2822			fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid);
2823		ret = -EINVAL;
2824	}
2825
2826	/*
2827	 * Hint to catch really bogus numbers, bitflips or so, more exact checks are
2828	 * done later
2829	 */
2830	if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) {
2831		btrfs_err(fs_info, "bytes_used is too small %llu",
2832			  btrfs_super_bytes_used(sb));
2833		ret = -EINVAL;
2834	}
2835	if (!is_power_of_2(btrfs_super_stripesize(sb))) {
2836		btrfs_err(fs_info, "invalid stripesize %u",
2837			  btrfs_super_stripesize(sb));
2838		ret = -EINVAL;
2839	}
2840	if (btrfs_super_num_devices(sb) > (1UL << 31))
2841		btrfs_warn(fs_info, "suspicious number of devices: %llu",
2842			   btrfs_super_num_devices(sb));
2843	if (btrfs_super_num_devices(sb) == 0) {
2844		btrfs_err(fs_info, "number of devices is 0");
2845		ret = -EINVAL;
2846	}
2847
2848	if (mirror_num >= 0 &&
2849	    btrfs_super_bytenr(sb) != btrfs_sb_offset(mirror_num)) {
2850		btrfs_err(fs_info, "super offset mismatch %llu != %u",
2851			  btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET);
2852		ret = -EINVAL;
2853	}
2854
2855	/*
2856	 * Obvious sys_chunk_array corruptions, it must hold at least one key
2857	 * and one chunk
2858	 */
2859	if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
2860		btrfs_err(fs_info, "system chunk array too big %u > %u",
2861			  btrfs_super_sys_array_size(sb),
2862			  BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
2863		ret = -EINVAL;
2864	}
2865	if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
2866			+ sizeof(struct btrfs_chunk)) {
2867		btrfs_err(fs_info, "system chunk array too small %u < %zu",
2868			  btrfs_super_sys_array_size(sb),
2869			  sizeof(struct btrfs_disk_key)
2870			  + sizeof(struct btrfs_chunk));
2871		ret = -EINVAL;
2872	}
2873
2874	/*
2875	 * The generation is a global counter, we'll trust it more than the others
2876	 * but it's still possible that it's the one that's wrong.
2877	 */
2878	if (btrfs_super_generation(sb) < btrfs_super_chunk_root_generation(sb))
2879		btrfs_warn(fs_info,
2880			"suspicious: generation < chunk_root_generation: %llu < %llu",
2881			btrfs_super_generation(sb),
2882			btrfs_super_chunk_root_generation(sb));
2883	if (btrfs_super_generation(sb) < btrfs_super_cache_generation(sb)
2884	    && btrfs_super_cache_generation(sb) != (u64)-1)
2885		btrfs_warn(fs_info,
2886			"suspicious: generation < cache_generation: %llu < %llu",
2887			btrfs_super_generation(sb),
2888			btrfs_super_cache_generation(sb));
2889
2890	return ret;
2891}
2892
2893/*
2894 * Validation of super block at mount time.
2895 * Some checks already done early at mount time, like csum type and incompat
2896 * flags will be skipped.
2897 */
2898static int btrfs_validate_mount_super(struct btrfs_fs_info *fs_info)
2899{
2900	return btrfs_validate_super(fs_info, fs_info->super_copy, 0);
2901}
2902
2903/*
2904 * Validation of super block at write time.
2905 * Some checks like bytenr check will be skipped as their values will be
2906 * overwritten soon.
2907 * Extra checks like csum type and incompat flags will be done here.
2908 */
2909static int btrfs_validate_write_super(struct btrfs_fs_info *fs_info,
2910				      struct btrfs_super_block *sb)
2911{
2912	int ret;
2913
2914	ret = btrfs_validate_super(fs_info, sb, -1);
2915	if (ret < 0)
2916		goto out;
2917	if (!btrfs_supported_super_csum(btrfs_super_csum_type(sb))) {
2918		ret = -EUCLEAN;
2919		btrfs_err(fs_info, "invalid csum type, has %u want %u",
2920			  btrfs_super_csum_type(sb), BTRFS_CSUM_TYPE_CRC32);
2921		goto out;
2922	}
2923	if (btrfs_super_incompat_flags(sb) & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
2924		ret = -EUCLEAN;
2925		btrfs_err(fs_info,
2926		"invalid incompat flags, has 0x%llx valid mask 0x%llx",
2927			  btrfs_super_incompat_flags(sb),
2928			  (unsigned long long)BTRFS_FEATURE_INCOMPAT_SUPP);
2929		goto out;
2930	}
2931out:
2932	if (ret < 0)
2933		btrfs_err(fs_info,
2934		"super block corruption detected before writing it to disk");
2935	return ret;
2936}
2937
2938static int load_super_root(struct btrfs_root *root, u64 bytenr, u64 gen, int level)
 
 
2939{
2940	struct btrfs_tree_parent_check check = {
2941		.level = level,
2942		.transid = gen,
2943		.owner_root = root->root_key.objectid
2944	};
2945	int ret = 0;
 
 
 
 
 
 
 
 
 
 
 
 
2946
2947	root->node = read_tree_block(root->fs_info, bytenr, &check);
2948	if (IS_ERR(root->node)) {
2949		ret = PTR_ERR(root->node);
2950		root->node = NULL;
2951		return ret;
2952	}
2953	if (!extent_buffer_uptodate(root->node)) {
2954		free_extent_buffer(root->node);
2955		root->node = NULL;
2956		return -EIO;
 
2957	}
2958
2959	btrfs_set_root_node(&root->root_item, root->node);
2960	root->commit_root = btrfs_root_node(root);
2961	btrfs_set_root_refs(&root->root_item, 1);
2962	return ret;
2963}
2964
2965static int load_important_roots(struct btrfs_fs_info *fs_info)
2966{
2967	struct btrfs_super_block *sb = fs_info->super_copy;
2968	u64 gen, bytenr;
2969	int level, ret;
2970
2971	bytenr = btrfs_super_root(sb);
2972	gen = btrfs_super_generation(sb);
2973	level = btrfs_super_root_level(sb);
2974	ret = load_super_root(fs_info->tree_root, bytenr, gen, level);
2975	if (ret) {
2976		btrfs_warn(fs_info, "couldn't read tree root");
2977		return ret;
2978	}
2979	return 0;
2980}
2981
2982static int __cold init_tree_roots(struct btrfs_fs_info *fs_info)
2983{
2984	int backup_index = find_newest_super_backup(fs_info);
2985	struct btrfs_super_block *sb = fs_info->super_copy;
2986	struct btrfs_root *tree_root = fs_info->tree_root;
2987	bool handle_error = false;
2988	int ret = 0;
2989	int i;
2990
2991	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
2992		if (handle_error) {
2993			if (!IS_ERR(tree_root->node))
2994				free_extent_buffer(tree_root->node);
2995			tree_root->node = NULL;
2996
2997			if (!btrfs_test_opt(fs_info, USEBACKUPROOT))
2998				break;
2999
3000			free_root_pointers(fs_info, 0);
3001
3002			/*
3003			 * Don't use the log in recovery mode, it won't be
3004			 * valid
3005			 */
3006			btrfs_set_super_log_root(sb, 0);
3007
3008			/* We can't trust the free space cache either */
3009			btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
3010
3011			ret = read_backup_root(fs_info, i);
3012			backup_index = ret;
3013			if (ret < 0)
3014				return ret;
3015		}
3016
3017		ret = load_important_roots(fs_info);
3018		if (ret) {
3019			handle_error = true;
3020			continue;
3021		}
3022
3023		/*
3024		 * No need to hold btrfs_root::objectid_mutex since the fs
3025		 * hasn't been fully initialised and we are the only user
3026		 */
3027		ret = btrfs_init_root_free_objectid(tree_root);
3028		if (ret < 0) {
3029			handle_error = true;
3030			continue;
3031		}
3032
3033		ASSERT(tree_root->free_objectid <= BTRFS_LAST_FREE_OBJECTID);
3034
3035		ret = btrfs_read_roots(fs_info);
3036		if (ret < 0) {
3037			handle_error = true;
3038			continue;
3039		}
3040
3041		/* All successful */
3042		fs_info->generation = btrfs_header_generation(tree_root->node);
3043		fs_info->last_trans_committed = fs_info->generation;
3044		fs_info->last_reloc_trans = 0;
3045
3046		/* Always begin writing backup roots after the one being used */
3047		if (backup_index < 0) {
3048			fs_info->backup_root_index = 0;
3049		} else {
3050			fs_info->backup_root_index = backup_index + 1;
3051			fs_info->backup_root_index %= BTRFS_NUM_BACKUP_ROOTS;
3052		}
3053		break;
3054	}
3055
3056	return ret;
3057}
3058
3059void btrfs_init_fs_info(struct btrfs_fs_info *fs_info)
3060{
3061	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
3062	INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC);
3063	INIT_LIST_HEAD(&fs_info->trans_list);
3064	INIT_LIST_HEAD(&fs_info->dead_roots);
3065	INIT_LIST_HEAD(&fs_info->delayed_iputs);
3066	INIT_LIST_HEAD(&fs_info->delalloc_roots);
3067	INIT_LIST_HEAD(&fs_info->caching_block_groups);
3068	spin_lock_init(&fs_info->delalloc_root_lock);
3069	spin_lock_init(&fs_info->trans_lock);
3070	spin_lock_init(&fs_info->fs_roots_radix_lock);
3071	spin_lock_init(&fs_info->delayed_iput_lock);
3072	spin_lock_init(&fs_info->defrag_inodes_lock);
 
3073	spin_lock_init(&fs_info->super_lock);
3074	spin_lock_init(&fs_info->buffer_lock);
3075	spin_lock_init(&fs_info->unused_bgs_lock);
3076	spin_lock_init(&fs_info->treelog_bg_lock);
3077	spin_lock_init(&fs_info->zone_active_bgs_lock);
3078	spin_lock_init(&fs_info->relocation_bg_lock);
3079	rwlock_init(&fs_info->tree_mod_log_lock);
3080	rwlock_init(&fs_info->global_root_lock);
3081	mutex_init(&fs_info->unused_bg_unpin_mutex);
3082	mutex_init(&fs_info->reclaim_bgs_lock);
3083	mutex_init(&fs_info->reloc_mutex);
3084	mutex_init(&fs_info->delalloc_root_mutex);
3085	mutex_init(&fs_info->zoned_meta_io_lock);
3086	mutex_init(&fs_info->zoned_data_reloc_io_lock);
3087	seqlock_init(&fs_info->profiles_lock);
3088
3089	btrfs_lockdep_init_map(fs_info, btrfs_trans_num_writers);
3090	btrfs_lockdep_init_map(fs_info, btrfs_trans_num_extwriters);
3091	btrfs_lockdep_init_map(fs_info, btrfs_trans_pending_ordered);
3092	btrfs_lockdep_init_map(fs_info, btrfs_ordered_extent);
3093	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_commit_start,
3094				     BTRFS_LOCKDEP_TRANS_COMMIT_START);
3095	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_unblocked,
3096				     BTRFS_LOCKDEP_TRANS_UNBLOCKED);
3097	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_super_committed,
3098				     BTRFS_LOCKDEP_TRANS_SUPER_COMMITTED);
3099	btrfs_state_lockdep_init_map(fs_info, btrfs_trans_completed,
3100				     BTRFS_LOCKDEP_TRANS_COMPLETED);
3101
3102	INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
3103	INIT_LIST_HEAD(&fs_info->space_info);
3104	INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
3105	INIT_LIST_HEAD(&fs_info->unused_bgs);
3106	INIT_LIST_HEAD(&fs_info->reclaim_bgs);
3107	INIT_LIST_HEAD(&fs_info->zone_active_bgs);
3108#ifdef CONFIG_BTRFS_DEBUG
3109	INIT_LIST_HEAD(&fs_info->allocated_roots);
3110	INIT_LIST_HEAD(&fs_info->allocated_ebs);
3111	spin_lock_init(&fs_info->eb_leak_lock);
3112#endif
3113	extent_map_tree_init(&fs_info->mapping_tree);
3114	btrfs_init_block_rsv(&fs_info->global_block_rsv,
3115			     BTRFS_BLOCK_RSV_GLOBAL);
3116	btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
3117	btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK);
3118	btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY);
3119	btrfs_init_block_rsv(&fs_info->delayed_block_rsv,
3120			     BTRFS_BLOCK_RSV_DELOPS);
3121	btrfs_init_block_rsv(&fs_info->delayed_refs_rsv,
3122			     BTRFS_BLOCK_RSV_DELREFS);
3123
3124	atomic_set(&fs_info->async_delalloc_pages, 0);
3125	atomic_set(&fs_info->defrag_running, 0);
 
3126	atomic_set(&fs_info->nr_delayed_iputs, 0);
3127	atomic64_set(&fs_info->tree_mod_seq, 0);
3128	fs_info->global_root_tree = RB_ROOT;
3129	fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE;
3130	fs_info->metadata_ratio = 0;
3131	fs_info->defrag_inodes = RB_ROOT;
3132	atomic64_set(&fs_info->free_chunk_space, 0);
3133	fs_info->tree_mod_log = RB_ROOT;
3134	fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
3135	fs_info->avg_delayed_ref_runtime = NSEC_PER_SEC >> 6; /* div by 64 */
 
 
 
3136	btrfs_init_ref_verify(fs_info);
3137
3138	fs_info->thread_pool_size = min_t(unsigned long,
3139					  num_online_cpus() + 2, 8);
3140
3141	INIT_LIST_HEAD(&fs_info->ordered_roots);
3142	spin_lock_init(&fs_info->ordered_root_lock);
3143
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3144	btrfs_init_scrub(fs_info);
3145#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3146	fs_info->check_integrity_print_mask = 0;
3147#endif
3148	btrfs_init_balance(fs_info);
3149	btrfs_init_async_reclaim_work(fs_info);
 
 
 
3150
3151	rwlock_init(&fs_info->block_group_cache_lock);
3152	fs_info->block_group_cache_tree = RB_ROOT_CACHED;
3153
3154	extent_io_tree_init(fs_info, &fs_info->excluded_extents,
3155			    IO_TREE_FS_EXCLUDED_EXTENTS);
 
 
 
 
 
 
 
 
3156
3157	mutex_init(&fs_info->ordered_operations_mutex);
3158	mutex_init(&fs_info->tree_log_mutex);
3159	mutex_init(&fs_info->chunk_mutex);
3160	mutex_init(&fs_info->transaction_kthread_mutex);
3161	mutex_init(&fs_info->cleaner_mutex);
3162	mutex_init(&fs_info->ro_block_group_mutex);
3163	init_rwsem(&fs_info->commit_root_sem);
3164	init_rwsem(&fs_info->cleanup_work_sem);
3165	init_rwsem(&fs_info->subvol_sem);
3166	sema_init(&fs_info->uuid_tree_rescan_sem, 1);
3167
3168	btrfs_init_dev_replace_locks(fs_info);
3169	btrfs_init_qgroup(fs_info);
3170	btrfs_discard_init(fs_info);
3171
3172	btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
3173	btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
3174
3175	init_waitqueue_head(&fs_info->transaction_throttle);
3176	init_waitqueue_head(&fs_info->transaction_wait);
3177	init_waitqueue_head(&fs_info->transaction_blocked_wait);
3178	init_waitqueue_head(&fs_info->async_submit_wait);
3179	init_waitqueue_head(&fs_info->delayed_iputs_wait);
3180
3181	/* Usable values until the real ones are cached from the superblock */
3182	fs_info->nodesize = 4096;
3183	fs_info->sectorsize = 4096;
3184	fs_info->sectorsize_bits = ilog2(4096);
3185	fs_info->stripesize = 4096;
3186
3187	fs_info->max_extent_size = BTRFS_MAX_EXTENT_SIZE;
3188
3189	spin_lock_init(&fs_info->swapfile_pins_lock);
3190	fs_info->swapfile_pins = RB_ROOT;
3191
3192	fs_info->bg_reclaim_threshold = BTRFS_DEFAULT_RECLAIM_THRESH;
3193	INIT_WORK(&fs_info->reclaim_bgs_work, btrfs_reclaim_bgs_work);
3194}
3195
3196static int init_mount_fs_info(struct btrfs_fs_info *fs_info, struct super_block *sb)
3197{
3198	int ret;
3199
3200	fs_info->sb = sb;
3201	sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE;
3202	sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE);
3203
3204	ret = percpu_counter_init(&fs_info->ordered_bytes, 0, GFP_KERNEL);
3205	if (ret)
3206		return ret;
3207
3208	ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0, GFP_KERNEL);
3209	if (ret)
3210		return ret;
3211
3212	fs_info->dirty_metadata_batch = PAGE_SIZE *
3213					(1 + ilog2(nr_cpu_ids));
3214
3215	ret = percpu_counter_init(&fs_info->delalloc_bytes, 0, GFP_KERNEL);
3216	if (ret)
3217		return ret;
3218
3219	ret = percpu_counter_init(&fs_info->dev_replace.bio_counter, 0,
3220			GFP_KERNEL);
3221	if (ret)
3222		return ret;
3223
3224	fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
3225					GFP_KERNEL);
3226	if (!fs_info->delayed_root)
3227		return -ENOMEM;
3228	btrfs_init_delayed_root(fs_info->delayed_root);
3229
3230	if (sb_rdonly(sb))
3231		set_bit(BTRFS_FS_STATE_RO, &fs_info->fs_state);
3232
3233	return btrfs_alloc_stripe_hash_table(fs_info);
3234}
3235
3236static int btrfs_uuid_rescan_kthread(void *data)
3237{
3238	struct btrfs_fs_info *fs_info = data;
3239	int ret;
3240
3241	/*
3242	 * 1st step is to iterate through the existing UUID tree and
3243	 * to delete all entries that contain outdated data.
3244	 * 2nd step is to add all missing entries to the UUID tree.
3245	 */
3246	ret = btrfs_uuid_tree_iterate(fs_info);
3247	if (ret < 0) {
3248		if (ret != -EINTR)
3249			btrfs_warn(fs_info, "iterating uuid_tree failed %d",
3250				   ret);
3251		up(&fs_info->uuid_tree_rescan_sem);
3252		return ret;
3253	}
3254	return btrfs_uuid_scan_kthread(data);
3255}
3256
3257static int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
3258{
3259	struct task_struct *task;
3260
3261	down(&fs_info->uuid_tree_rescan_sem);
3262	task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
3263	if (IS_ERR(task)) {
3264		/* fs_info->update_uuid_tree_gen remains 0 in all error case */
3265		btrfs_warn(fs_info, "failed to start uuid_rescan task");
3266		up(&fs_info->uuid_tree_rescan_sem);
3267		return PTR_ERR(task);
3268	}
3269
3270	return 0;
3271}
3272
3273/*
3274 * Some options only have meaning at mount time and shouldn't persist across
3275 * remounts, or be displayed. Clear these at the end of mount and remount
3276 * code paths.
3277 */
3278void btrfs_clear_oneshot_options(struct btrfs_fs_info *fs_info)
3279{
3280	btrfs_clear_opt(fs_info->mount_opt, USEBACKUPROOT);
3281	btrfs_clear_opt(fs_info->mount_opt, CLEAR_CACHE);
3282}
3283
3284/*
3285 * Mounting logic specific to read-write file systems. Shared by open_ctree
3286 * and btrfs_remount when remounting from read-only to read-write.
3287 */
3288int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info)
3289{
3290	int ret;
3291	const bool cache_opt = btrfs_test_opt(fs_info, SPACE_CACHE);
3292	bool clear_free_space_tree = false;
3293
3294	if (btrfs_test_opt(fs_info, CLEAR_CACHE) &&
3295	    btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3296		clear_free_space_tree = true;
3297	} else if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
3298		   !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID)) {
3299		btrfs_warn(fs_info, "free space tree is invalid");
3300		clear_free_space_tree = true;
3301	}
3302
3303	if (clear_free_space_tree) {
3304		btrfs_info(fs_info, "clearing free space tree");
3305		ret = btrfs_clear_free_space_tree(fs_info);
3306		if (ret) {
3307			btrfs_warn(fs_info,
3308				   "failed to clear free space tree: %d", ret);
3309			goto out;
3310		}
3311	}
3312
3313	/*
3314	 * btrfs_find_orphan_roots() is responsible for finding all the dead
3315	 * roots (with 0 refs), flag them with BTRFS_ROOT_DEAD_TREE and load
3316	 * them into the fs_info->fs_roots_radix tree. This must be done before
3317	 * calling btrfs_orphan_cleanup() on the tree root. If we don't do it
3318	 * first, then btrfs_orphan_cleanup() will delete a dead root's orphan
3319	 * item before the root's tree is deleted - this means that if we unmount
3320	 * or crash before the deletion completes, on the next mount we will not
3321	 * delete what remains of the tree because the orphan item does not
3322	 * exists anymore, which is what tells us we have a pending deletion.
3323	 */
3324	ret = btrfs_find_orphan_roots(fs_info);
3325	if (ret)
3326		goto out;
3327
3328	ret = btrfs_cleanup_fs_roots(fs_info);
3329	if (ret)
3330		goto out;
3331
3332	down_read(&fs_info->cleanup_work_sem);
3333	if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) ||
3334	    (ret = btrfs_orphan_cleanup(fs_info->tree_root))) {
3335		up_read(&fs_info->cleanup_work_sem);
3336		goto out;
3337	}
3338	up_read(&fs_info->cleanup_work_sem);
3339
3340	mutex_lock(&fs_info->cleaner_mutex);
3341	ret = btrfs_recover_relocation(fs_info);
3342	mutex_unlock(&fs_info->cleaner_mutex);
3343	if (ret < 0) {
3344		btrfs_warn(fs_info, "failed to recover relocation: %d", ret);
3345		goto out;
3346	}
3347
3348	if (btrfs_test_opt(fs_info, FREE_SPACE_TREE) &&
3349	    !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3350		btrfs_info(fs_info, "creating free space tree");
3351		ret = btrfs_create_free_space_tree(fs_info);
3352		if (ret) {
3353			btrfs_warn(fs_info,
3354				"failed to create free space tree: %d", ret);
3355			goto out;
3356		}
3357	}
3358
3359	if (cache_opt != btrfs_free_space_cache_v1_active(fs_info)) {
3360		ret = btrfs_set_free_space_cache_v1_active(fs_info, cache_opt);
3361		if (ret)
3362			goto out;
3363	}
3364
3365	ret = btrfs_resume_balance_async(fs_info);
3366	if (ret)
3367		goto out;
3368
3369	ret = btrfs_resume_dev_replace_async(fs_info);
3370	if (ret) {
3371		btrfs_warn(fs_info, "failed to resume dev_replace");
3372		goto out;
3373	}
3374
3375	btrfs_qgroup_rescan_resume(fs_info);
3376
3377	if (!fs_info->uuid_root) {
3378		btrfs_info(fs_info, "creating UUID tree");
3379		ret = btrfs_create_uuid_tree(fs_info);
3380		if (ret) {
3381			btrfs_warn(fs_info,
3382				   "failed to create the UUID tree %d", ret);
3383			goto out;
3384		}
3385	}
3386
3387out:
3388	return ret;
3389}
3390
3391/*
3392 * Do various sanity and dependency checks of different features.
3393 *
3394 * @is_rw_mount:	If the mount is read-write.
3395 *
3396 * This is the place for less strict checks (like for subpage or artificial
3397 * feature dependencies).
3398 *
3399 * For strict checks or possible corruption detection, see
3400 * btrfs_validate_super().
3401 *
3402 * This should be called after btrfs_parse_options(), as some mount options
3403 * (space cache related) can modify on-disk format like free space tree and
3404 * screw up certain feature dependencies.
3405 */
3406int btrfs_check_features(struct btrfs_fs_info *fs_info, bool is_rw_mount)
3407{
3408	struct btrfs_super_block *disk_super = fs_info->super_copy;
3409	u64 incompat = btrfs_super_incompat_flags(disk_super);
3410	const u64 compat_ro = btrfs_super_compat_ro_flags(disk_super);
3411	const u64 compat_ro_unsupp = (compat_ro & ~BTRFS_FEATURE_COMPAT_RO_SUPP);
3412
3413	if (incompat & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
3414		btrfs_err(fs_info,
3415		"cannot mount because of unknown incompat features (0x%llx)",
3416		    incompat);
3417		return -EINVAL;
3418	}
3419
3420	/* Runtime limitation for mixed block groups. */
3421	if ((incompat & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
3422	    (fs_info->sectorsize != fs_info->nodesize)) {
3423		btrfs_err(fs_info,
3424"unequal nodesize/sectorsize (%u != %u) are not allowed for mixed block groups",
3425			fs_info->nodesize, fs_info->sectorsize);
3426		return -EINVAL;
3427	}
3428
3429	/* Mixed backref is an always-enabled feature. */
3430	incompat |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
3431
3432	/* Set compression related flags just in case. */
3433	if (fs_info->compress_type == BTRFS_COMPRESS_LZO)
3434		incompat |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
3435	else if (fs_info->compress_type == BTRFS_COMPRESS_ZSTD)
3436		incompat |= BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD;
3437
3438	/*
3439	 * An ancient flag, which should really be marked deprecated.
3440	 * Such runtime limitation doesn't really need a incompat flag.
3441	 */
3442	if (btrfs_super_nodesize(disk_super) > PAGE_SIZE)
3443		incompat |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
3444
3445	if (compat_ro_unsupp && is_rw_mount) {
3446		btrfs_err(fs_info,
3447	"cannot mount read-write because of unknown compat_ro features (0x%llx)",
3448		       compat_ro);
3449		return -EINVAL;
3450	}
3451
3452	/*
3453	 * We have unsupported RO compat features, although RO mounted, we
3454	 * should not cause any metadata writes, including log replay.
3455	 * Or we could screw up whatever the new feature requires.
3456	 */
3457	if (compat_ro_unsupp && btrfs_super_log_root(disk_super) &&
3458	    !btrfs_test_opt(fs_info, NOLOGREPLAY)) {
3459		btrfs_err(fs_info,
3460"cannot replay dirty log with unsupported compat_ro features (0x%llx), try rescue=nologreplay",
3461			  compat_ro);
3462		return -EINVAL;
3463	}
3464
3465	/*
3466	 * Artificial limitations for block group tree, to force
3467	 * block-group-tree to rely on no-holes and free-space-tree.
3468	 */
3469	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE) &&
3470	    (!btrfs_fs_incompat(fs_info, NO_HOLES) ||
3471	     !btrfs_test_opt(fs_info, FREE_SPACE_TREE))) {
3472		btrfs_err(fs_info,
3473"block-group-tree feature requires no-holes and free-space-tree features");
3474		return -EINVAL;
3475	}
3476
3477	/*
3478	 * Subpage runtime limitation on v1 cache.
3479	 *
3480	 * V1 space cache still has some hard codeed PAGE_SIZE usage, while
3481	 * we're already defaulting to v2 cache, no need to bother v1 as it's
3482	 * going to be deprecated anyway.
3483	 */
3484	if (fs_info->sectorsize < PAGE_SIZE && btrfs_test_opt(fs_info, SPACE_CACHE)) {
3485		btrfs_warn(fs_info,
3486	"v1 space cache is not supported for page size %lu with sectorsize %u",
3487			   PAGE_SIZE, fs_info->sectorsize);
3488		return -EINVAL;
3489	}
3490
3491	/* This can be called by remount, we need to protect the super block. */
3492	spin_lock(&fs_info->super_lock);
3493	btrfs_set_super_incompat_flags(disk_super, incompat);
3494	spin_unlock(&fs_info->super_lock);
3495
3496	return 0;
3497}
3498
3499int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_devices,
3500		      char *options)
3501{
3502	u32 sectorsize;
3503	u32 nodesize;
3504	u32 stripesize;
3505	u64 generation;
3506	u64 features;
3507	u16 csum_type;
3508	struct btrfs_super_block *disk_super;
3509	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
3510	struct btrfs_root *tree_root;
3511	struct btrfs_root *chunk_root;
3512	int ret;
3513	int err = -EINVAL;
3514	int level;
3515
3516	ret = init_mount_fs_info(fs_info, sb);
3517	if (ret) {
3518		err = ret;
3519		goto fail;
3520	}
3521
3522	/* These need to be init'ed before we start creating inodes and such. */
3523	tree_root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID,
3524				     GFP_KERNEL);
3525	fs_info->tree_root = tree_root;
3526	chunk_root = btrfs_alloc_root(fs_info, BTRFS_CHUNK_TREE_OBJECTID,
3527				      GFP_KERNEL);
3528	fs_info->chunk_root = chunk_root;
3529	if (!tree_root || !chunk_root) {
3530		err = -ENOMEM;
3531		goto fail;
3532	}
3533
3534	fs_info->btree_inode = new_inode(sb);
3535	if (!fs_info->btree_inode) {
3536		err = -ENOMEM;
3537		goto fail;
3538	}
3539	mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
3540	btrfs_init_btree_inode(fs_info);
3541
3542	invalidate_bdev(fs_devices->latest_dev->bdev);
3543
3544	/*
3545	 * Read super block and check the signature bytes only
3546	 */
3547	disk_super = btrfs_read_dev_super(fs_devices->latest_dev->bdev);
3548	if (IS_ERR(disk_super)) {
3549		err = PTR_ERR(disk_super);
3550		goto fail_alloc;
3551	}
3552
3553	/*
3554	 * Verify the type first, if that or the checksum value are
3555	 * corrupted, we'll find out
3556	 */
3557	csum_type = btrfs_super_csum_type(disk_super);
3558	if (!btrfs_supported_super_csum(csum_type)) {
3559		btrfs_err(fs_info, "unsupported checksum algorithm: %u",
3560			  csum_type);
3561		err = -EINVAL;
3562		btrfs_release_disk_super(disk_super);
3563		goto fail_alloc;
3564	}
3565
3566	fs_info->csum_size = btrfs_super_csum_size(disk_super);
3567
3568	ret = btrfs_init_csum_hash(fs_info, csum_type);
3569	if (ret) {
3570		err = ret;
3571		btrfs_release_disk_super(disk_super);
3572		goto fail_alloc;
3573	}
3574
3575	/*
3576	 * We want to check superblock checksum, the type is stored inside.
3577	 * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k).
3578	 */
3579	if (btrfs_check_super_csum(fs_info, disk_super)) {
3580		btrfs_err(fs_info, "superblock checksum mismatch");
3581		err = -EINVAL;
3582		btrfs_release_disk_super(disk_super);
3583		goto fail_alloc;
3584	}
3585
3586	/*
3587	 * super_copy is zeroed at allocation time and we never touch the
3588	 * following bytes up to INFO_SIZE, the checksum is calculated from
3589	 * the whole block of INFO_SIZE
3590	 */
3591	memcpy(fs_info->super_copy, disk_super, sizeof(*fs_info->super_copy));
3592	btrfs_release_disk_super(disk_super);
3593
3594	disk_super = fs_info->super_copy;
3595
 
 
 
 
 
 
 
 
3596
3597	features = btrfs_super_flags(disk_super);
3598	if (features & BTRFS_SUPER_FLAG_CHANGING_FSID_V2) {
3599		features &= ~BTRFS_SUPER_FLAG_CHANGING_FSID_V2;
3600		btrfs_set_super_flags(disk_super, features);
3601		btrfs_info(fs_info,
3602			"found metadata UUID change in progress flag, clearing");
3603	}
3604
3605	memcpy(fs_info->super_for_commit, fs_info->super_copy,
3606	       sizeof(*fs_info->super_for_commit));
3607
3608	ret = btrfs_validate_mount_super(fs_info);
3609	if (ret) {
3610		btrfs_err(fs_info, "superblock contains fatal errors");
3611		err = -EINVAL;
3612		goto fail_alloc;
3613	}
3614
3615	if (!btrfs_super_root(disk_super))
3616		goto fail_alloc;
3617
3618	/* check FS state, whether FS is broken. */
3619	if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
3620		set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state);
3621
3622	/*
 
 
 
 
 
 
 
3623	 * In the long term, we'll store the compression type in the super
3624	 * block, and it'll be used for per file compression control.
3625	 */
3626	fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
3627
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3628
3629	/* Set up fs_info before parsing mount options */
3630	nodesize = btrfs_super_nodesize(disk_super);
3631	sectorsize = btrfs_super_sectorsize(disk_super);
3632	stripesize = sectorsize;
3633	fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids));
3634	fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
3635
 
3636	fs_info->nodesize = nodesize;
3637	fs_info->sectorsize = sectorsize;
3638	fs_info->sectorsize_bits = ilog2(sectorsize);
3639	fs_info->csums_per_leaf = BTRFS_MAX_ITEM_SIZE(fs_info) / fs_info->csum_size;
3640	fs_info->stripesize = stripesize;
3641
3642	ret = btrfs_parse_options(fs_info, options, sb->s_flags);
3643	if (ret) {
3644		err = ret;
3645		goto fail_alloc;
 
 
 
 
 
 
3646	}
3647
3648	ret = btrfs_check_features(fs_info, !sb_rdonly(sb));
3649	if (ret < 0) {
3650		err = ret;
3651		goto fail_alloc;
3652	}
3653
3654	if (sectorsize < PAGE_SIZE) {
3655		struct btrfs_subpage_info *subpage_info;
3656
3657		/*
3658		 * V1 space cache has some hardcoded PAGE_SIZE usage, and is
3659		 * going to be deprecated.
3660		 *
3661		 * Force to use v2 cache for subpage case.
3662		 */
3663		btrfs_clear_opt(fs_info->mount_opt, SPACE_CACHE);
3664		btrfs_set_and_info(fs_info, FREE_SPACE_TREE,
3665			"forcing free space tree for sector size %u with page size %lu",
3666			sectorsize, PAGE_SIZE);
3667
3668		btrfs_warn(fs_info,
3669		"read-write for sector size %u with page size %lu is experimental",
3670			   sectorsize, PAGE_SIZE);
3671		subpage_info = kzalloc(sizeof(*subpage_info), GFP_KERNEL);
3672		if (!subpage_info)
3673			goto fail_alloc;
3674		btrfs_init_subpage_info(subpage_info, sectorsize);
3675		fs_info->subpage_info = subpage_info;
3676	}
3677
3678	ret = btrfs_init_workqueues(fs_info);
3679	if (ret) {
3680		err = ret;
3681		goto fail_sb_buffer;
3682	}
3683
 
 
 
 
3684	sb->s_bdi->ra_pages *= btrfs_super_num_devices(disk_super);
3685	sb->s_bdi->ra_pages = max(sb->s_bdi->ra_pages, SZ_4M / PAGE_SIZE);
3686
3687	sb->s_blocksize = sectorsize;
3688	sb->s_blocksize_bits = blksize_bits(sectorsize);
3689	memcpy(&sb->s_uuid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE);
3690
3691	mutex_lock(&fs_info->chunk_mutex);
3692	ret = btrfs_read_sys_array(fs_info);
3693	mutex_unlock(&fs_info->chunk_mutex);
3694	if (ret) {
3695		btrfs_err(fs_info, "failed to read the system array: %d", ret);
3696		goto fail_sb_buffer;
3697	}
3698
3699	generation = btrfs_super_chunk_root_generation(disk_super);
3700	level = btrfs_super_chunk_root_level(disk_super);
3701	ret = load_super_root(chunk_root, btrfs_super_chunk_root(disk_super),
3702			      generation, level);
3703	if (ret) {
 
 
 
 
 
3704		btrfs_err(fs_info, "failed to read chunk root");
 
 
 
3705		goto fail_tree_roots;
3706	}
 
 
3707
3708	read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
3709			   offsetof(struct btrfs_header, chunk_tree_uuid),
3710			   BTRFS_UUID_SIZE);
3711
3712	ret = btrfs_read_chunk_tree(fs_info);
3713	if (ret) {
3714		btrfs_err(fs_info, "failed to read chunk tree: %d", ret);
3715		goto fail_tree_roots;
3716	}
3717
3718	/*
3719	 * At this point we know all the devices that make this filesystem,
3720	 * including the seed devices but we don't know yet if the replace
3721	 * target is required. So free devices that are not part of this
3722	 * filesystem but skip the replace target device which is checked
3723	 * below in btrfs_init_dev_replace().
3724	 */
3725	btrfs_free_extra_devids(fs_devices);
3726	if (!fs_devices->latest_dev->bdev) {
 
3727		btrfs_err(fs_info, "failed to read devices");
3728		goto fail_tree_roots;
3729	}
3730
3731	ret = init_tree_roots(fs_info);
3732	if (ret)
3733		goto fail_tree_roots;
3734
3735	/*
3736	 * Get zone type information of zoned block devices. This will also
3737	 * handle emulation of a zoned filesystem if a regular device has the
3738	 * zoned incompat feature flag set.
3739	 */
3740	ret = btrfs_get_dev_zone_info_all_devices(fs_info);
 
 
 
 
 
 
 
 
 
 
 
 
 
3741	if (ret) {
3742		btrfs_err(fs_info,
3743			  "zoned: failed to read device zone info: %d",
3744			  ret);
3745		goto fail_block_groups;
3746	}
3747
3748	/*
3749	 * If we have a uuid root and we're not being told to rescan we need to
3750	 * check the generation here so we can set the
3751	 * BTRFS_FS_UPDATE_UUID_TREE_GEN bit.  Otherwise we could commit the
3752	 * transaction during a balance or the log replay without updating the
3753	 * uuid generation, and then if we crash we would rescan the uuid tree,
3754	 * even though it was perfectly fine.
3755	 */
3756	if (fs_info->uuid_root && !btrfs_test_opt(fs_info, RESCAN_UUID_TREE) &&
3757	    fs_info->generation == btrfs_super_uuid_tree_generation(disk_super))
3758		set_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags);
3759
3760	ret = btrfs_verify_dev_extents(fs_info);
3761	if (ret) {
3762		btrfs_err(fs_info,
3763			  "failed to verify dev extents against chunks: %d",
3764			  ret);
3765		goto fail_block_groups;
3766	}
3767	ret = btrfs_recover_balance(fs_info);
3768	if (ret) {
3769		btrfs_err(fs_info, "failed to recover balance: %d", ret);
3770		goto fail_block_groups;
3771	}
3772
3773	ret = btrfs_init_dev_stats(fs_info);
3774	if (ret) {
3775		btrfs_err(fs_info, "failed to init dev_stats: %d", ret);
3776		goto fail_block_groups;
3777	}
3778
3779	ret = btrfs_init_dev_replace(fs_info);
3780	if (ret) {
3781		btrfs_err(fs_info, "failed to init dev_replace: %d", ret);
3782		goto fail_block_groups;
3783	}
3784
3785	ret = btrfs_check_zoned_mode(fs_info);
 
 
3786	if (ret) {
3787		btrfs_err(fs_info, "failed to initialize zoned mode: %d",
3788			  ret);
3789		goto fail_block_groups;
3790	}
3791
3792	ret = btrfs_sysfs_add_fsid(fs_devices);
3793	if (ret) {
3794		btrfs_err(fs_info, "failed to init sysfs fsid interface: %d",
3795				ret);
3796		goto fail_block_groups;
3797	}
3798
3799	ret = btrfs_sysfs_add_mounted(fs_info);
3800	if (ret) {
3801		btrfs_err(fs_info, "failed to init sysfs interface: %d", ret);
3802		goto fail_fsdev_sysfs;
3803	}
3804
3805	ret = btrfs_init_space_info(fs_info);
3806	if (ret) {
3807		btrfs_err(fs_info, "failed to initialize space info: %d", ret);
3808		goto fail_sysfs;
3809	}
3810
3811	ret = btrfs_read_block_groups(fs_info);
3812	if (ret) {
3813		btrfs_err(fs_info, "failed to read block groups: %d", ret);
3814		goto fail_sysfs;
3815	}
3816
3817	btrfs_free_zone_cache(fs_info);
3818
3819	if (!sb_rdonly(sb) && fs_info->fs_devices->missing_devices &&
3820	    !btrfs_check_rw_degradable(fs_info, NULL)) {
3821		btrfs_warn(fs_info,
3822		"writable mount is not allowed due to too many missing devices");
3823		goto fail_sysfs;
3824	}
3825
3826	fs_info->cleaner_kthread = kthread_run(cleaner_kthread, fs_info,
3827					       "btrfs-cleaner");
3828	if (IS_ERR(fs_info->cleaner_kthread))
3829		goto fail_sysfs;
3830
3831	fs_info->transaction_kthread = kthread_run(transaction_kthread,
3832						   tree_root,
3833						   "btrfs-transaction");
3834	if (IS_ERR(fs_info->transaction_kthread))
3835		goto fail_cleaner;
3836
3837	if (!btrfs_test_opt(fs_info, NOSSD) &&
3838	    !fs_info->fs_devices->rotating) {
3839		btrfs_set_and_info(fs_info, SSD, "enabling ssd optimizations");
3840	}
3841
3842	/*
3843	 * For devices supporting discard turn on discard=async automatically,
3844	 * unless it's already set or disabled. This could be turned off by
3845	 * nodiscard for the same mount.
3846	 */
3847	if (!(btrfs_test_opt(fs_info, DISCARD_SYNC) ||
3848	      btrfs_test_opt(fs_info, DISCARD_ASYNC) ||
3849	      btrfs_test_opt(fs_info, NODISCARD)) &&
3850	    fs_info->fs_devices->discardable) {
3851		btrfs_set_and_info(fs_info, DISCARD_ASYNC,
3852				   "auto enabling async discard");
3853		btrfs_clear_opt(fs_info->mount_opt, NODISCARD);
3854	}
3855
3856#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3857	if (btrfs_test_opt(fs_info, CHECK_INTEGRITY)) {
3858		ret = btrfsic_mount(fs_info, fs_devices,
3859				    btrfs_test_opt(fs_info,
3860					CHECK_INTEGRITY_DATA) ? 1 : 0,
 
3861				    fs_info->check_integrity_print_mask);
3862		if (ret)
3863			btrfs_warn(fs_info,
3864				"failed to initialize integrity check module: %d",
3865				ret);
3866	}
3867#endif
3868	ret = btrfs_read_qgroup_config(fs_info);
3869	if (ret)
3870		goto fail_trans_kthread;
3871
3872	if (btrfs_build_ref_tree(fs_info))
3873		btrfs_err(fs_info, "couldn't build ref tree");
3874
3875	/* do not make disk changes in broken FS or nologreplay is given */
3876	if (btrfs_super_log_root(disk_super) != 0 &&
3877	    !btrfs_test_opt(fs_info, NOLOGREPLAY)) {
3878		btrfs_info(fs_info, "start tree-log replay");
3879		ret = btrfs_replay_log(fs_info, fs_devices);
3880		if (ret) {
3881			err = ret;
3882			goto fail_qgroup;
3883		}
3884	}
3885
3886	fs_info->fs_root = btrfs_get_fs_root(fs_info, BTRFS_FS_TREE_OBJECTID, true);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3887	if (IS_ERR(fs_info->fs_root)) {
3888		err = PTR_ERR(fs_info->fs_root);
3889		btrfs_warn(fs_info, "failed to read fs tree: %d", err);
3890		fs_info->fs_root = NULL;
3891		goto fail_qgroup;
3892	}
3893
3894	if (sb_rdonly(sb))
3895		goto clear_oneshot;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3896
3897	ret = btrfs_start_pre_rw_mount(fs_info);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3898	if (ret) {
 
3899		close_ctree(fs_info);
3900		return ret;
3901	}
3902	btrfs_discard_resume(fs_info);
3903
3904	if (fs_info->uuid_root &&
3905	    (btrfs_test_opt(fs_info, RESCAN_UUID_TREE) ||
3906	     fs_info->generation != btrfs_super_uuid_tree_generation(disk_super))) {
 
 
 
 
 
 
 
 
 
 
 
3907		btrfs_info(fs_info, "checking UUID tree");
3908		ret = btrfs_check_uuid_tree(fs_info);
3909		if (ret) {
3910			btrfs_warn(fs_info,
3911				"failed to check the UUID tree: %d", ret);
3912			close_ctree(fs_info);
3913			return ret;
3914		}
 
 
3915	}
3916
3917	set_bit(BTRFS_FS_OPEN, &fs_info->flags);
3918
3919	/* Kick the cleaner thread so it'll start deleting snapshots. */
3920	if (test_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags))
3921		wake_up_process(fs_info->cleaner_kthread);
 
 
3922
3923clear_oneshot:
3924	btrfs_clear_oneshot_options(fs_info);
3925	return 0;
3926
3927fail_qgroup:
3928	btrfs_free_qgroup_config(fs_info);
3929fail_trans_kthread:
3930	kthread_stop(fs_info->transaction_kthread);
3931	btrfs_cleanup_transaction(fs_info);
3932	btrfs_free_fs_roots(fs_info);
3933fail_cleaner:
3934	kthread_stop(fs_info->cleaner_kthread);
3935
3936	/*
3937	 * make sure we're done with the btree inode before we stop our
3938	 * kthreads
3939	 */
3940	filemap_write_and_wait(fs_info->btree_inode->i_mapping);
3941
3942fail_sysfs:
3943	btrfs_sysfs_remove_mounted(fs_info);
3944
3945fail_fsdev_sysfs:
3946	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
3947
3948fail_block_groups:
3949	btrfs_put_block_group_cache(fs_info);
3950
3951fail_tree_roots:
3952	if (fs_info->data_reloc_root)
3953		btrfs_drop_and_free_fs_root(fs_info, fs_info->data_reloc_root);
3954	free_root_pointers(fs_info, true);
3955	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
3956
3957fail_sb_buffer:
3958	btrfs_stop_all_workers(fs_info);
3959	btrfs_free_block_groups(fs_info);
 
 
3960fail_alloc:
 
3961	btrfs_mapping_tree_free(&fs_info->mapping_tree);
3962
3963	iput(fs_info->btree_inode);
 
 
 
 
 
 
 
 
 
 
3964fail:
 
3965	btrfs_close_devices(fs_info->fs_devices);
3966	return err;
3967}
3968ALLOW_ERROR_INJECTION(open_ctree, ERRNO);
3969
3970static void btrfs_end_super_write(struct bio *bio)
3971{
3972	struct btrfs_device *device = bio->bi_private;
3973	struct bio_vec *bvec;
3974	struct bvec_iter_all iter_all;
3975	struct page *page;
3976
3977	bio_for_each_segment_all(bvec, bio, iter_all) {
3978		page = bvec->bv_page;
3979
3980		if (bio->bi_status) {
3981			btrfs_warn_rl_in_rcu(device->fs_info,
3982				"lost page write due to IO error on %s (%d)",
3983				btrfs_dev_name(device),
3984				blk_status_to_errno(bio->bi_status));
3985			ClearPageUptodate(page);
3986			SetPageError(page);
3987			btrfs_dev_stat_inc_and_print(device,
3988						     BTRFS_DEV_STAT_WRITE_ERRS);
3989		} else {
3990			SetPageUptodate(page);
3991		}
3992
3993		put_page(page);
3994		unlock_page(page);
3995	}
3996
3997	bio_put(bio);
 
 
 
 
3998}
 
3999
4000struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
4001						   int copy_num, bool drop_cache)
4002{
4003	struct btrfs_super_block *super;
4004	struct page *page;
4005	u64 bytenr, bytenr_orig;
4006	struct address_space *mapping = bdev->bd_inode->i_mapping;
4007	int ret;
4008
4009	bytenr_orig = btrfs_sb_offset(copy_num);
4010	ret = btrfs_sb_log_location_bdev(bdev, copy_num, READ, &bytenr);
4011	if (ret == -ENOENT)
4012		return ERR_PTR(-EINVAL);
4013	else if (ret)
4014		return ERR_PTR(ret);
4015
4016	if (bytenr + BTRFS_SUPER_INFO_SIZE >= bdev_nr_bytes(bdev))
4017		return ERR_PTR(-EINVAL);
4018
4019	if (drop_cache) {
4020		/* This should only be called with the primary sb. */
4021		ASSERT(copy_num == 0);
4022
4023		/*
4024		 * Drop the page of the primary superblock, so later read will
4025		 * always read from the device.
4026		 */
4027		invalidate_inode_pages2_range(mapping,
4028				bytenr >> PAGE_SHIFT,
4029				(bytenr + BTRFS_SUPER_INFO_SIZE) >> PAGE_SHIFT);
4030	}
 
 
 
 
 
 
 
 
 
 
4031
4032	page = read_cache_page_gfp(mapping, bytenr >> PAGE_SHIFT, GFP_NOFS);
4033	if (IS_ERR(page))
4034		return ERR_CAST(page);
4035
4036	super = page_address(page);
4037	if (btrfs_super_magic(super) != BTRFS_MAGIC) {
4038		btrfs_release_disk_super(super);
4039		return ERR_PTR(-ENODATA);
4040	}
 
 
4041
4042	if (btrfs_super_bytenr(super) != bytenr_orig) {
4043		btrfs_release_disk_super(super);
4044		return ERR_PTR(-EINVAL);
 
 
4045	}
4046
4047	return super;
 
4048}
4049
4050
4051struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev)
4052{
4053	struct btrfs_super_block *super, *latest = NULL;
 
 
4054	int i;
4055	u64 transid = 0;
 
4056
4057	/* we would like to check all the supers, but that would make
4058	 * a btrfs mount succeed after a mkfs from a different FS.
4059	 * So, we need to add a special mount option to scan for
4060	 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
4061	 */
4062	for (i = 0; i < 1; i++) {
4063		super = btrfs_read_dev_one_super(bdev, i, false);
4064		if (IS_ERR(super))
4065			continue;
4066
 
 
4067		if (!latest || btrfs_super_generation(super) > transid) {
4068			if (latest)
4069				btrfs_release_disk_super(super);
4070
4071			latest = super;
4072			transid = btrfs_super_generation(super);
 
 
4073		}
4074	}
4075
4076	return super;
 
 
 
4077}
4078
4079/*
4080 * Write superblock @sb to the @device. Do not wait for completion, all the
4081 * pages we use for writing are locked.
4082 *
4083 * Write @max_mirrors copies of the superblock, where 0 means default that fit
4084 * the expected device size at commit time. Note that max_mirrors must be
4085 * same for write and wait phases.
4086 *
4087 * Return number of errors when page is not found or submission fails.
4088 */
4089static int write_dev_supers(struct btrfs_device *device,
4090			    struct btrfs_super_block *sb, int max_mirrors)
4091{
4092	struct btrfs_fs_info *fs_info = device->fs_info;
4093	struct address_space *mapping = device->bdev->bd_inode->i_mapping;
4094	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 
4095	int i;
 
4096	int errors = 0;
4097	int ret;
4098	u64 bytenr, bytenr_orig;
4099
4100	if (max_mirrors == 0)
4101		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
4102
4103	shash->tfm = fs_info->csum_shash;
4104
4105	for (i = 0; i < max_mirrors; i++) {
4106		struct page *page;
4107		struct bio *bio;
4108		struct btrfs_super_block *disk_super;
4109
4110		bytenr_orig = btrfs_sb_offset(i);
4111		ret = btrfs_sb_log_location(device, i, WRITE, &bytenr);
4112		if (ret == -ENOENT) {
4113			continue;
4114		} else if (ret < 0) {
4115			btrfs_err(device->fs_info,
4116				"couldn't get super block location for mirror %d",
4117				i);
4118			errors++;
4119			continue;
4120		}
4121		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
4122		    device->commit_total_bytes)
4123			break;
4124
4125		btrfs_set_super_bytenr(sb, bytenr_orig);
4126
4127		crypto_shash_digest(shash, (const char *)sb + BTRFS_CSUM_SIZE,
4128				    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE,
4129				    sb->csum);
4130
4131		page = find_or_create_page(mapping, bytenr >> PAGE_SHIFT,
4132					   GFP_NOFS);
4133		if (!page) {
 
 
4134			btrfs_err(device->fs_info,
4135			    "couldn't get super block page for bytenr %llu",
4136			    bytenr);
4137			errors++;
4138			continue;
4139		}
4140
4141		/* Bump the refcount for wait_dev_supers() */
4142		get_page(page);
4143
4144		disk_super = page_address(page);
4145		memcpy(disk_super, sb, BTRFS_SUPER_INFO_SIZE);
4146
4147		/*
4148		 * Directly use bios here instead of relying on the page cache
4149		 * to do I/O, so we don't lose the ability to do integrity
4150		 * checking.
4151		 */
4152		bio = bio_alloc(device->bdev, 1,
4153				REQ_OP_WRITE | REQ_SYNC | REQ_META | REQ_PRIO,
4154				GFP_NOFS);
4155		bio->bi_iter.bi_sector = bytenr >> SECTOR_SHIFT;
4156		bio->bi_private = device;
4157		bio->bi_end_io = btrfs_end_super_write;
4158		__bio_add_page(bio, page, BTRFS_SUPER_INFO_SIZE,
4159			       offset_in_page(bytenr));
4160
4161		/*
4162		 * We FUA only the first super block.  The others we allow to
4163		 * go down lazy and there's a short window where the on-disk
4164		 * copies might still contain the older version.
4165		 */
 
4166		if (i == 0 && !btrfs_test_opt(device->fs_info, NOBARRIER))
4167			bio->bi_opf |= REQ_FUA;
4168
4169		btrfsic_check_bio(bio);
4170		submit_bio(bio);
4171
4172		if (btrfs_advance_sb_log(device, i))
4173			errors++;
4174	}
4175	return errors < i ? 0 : -1;
4176}
4177
4178/*
4179 * Wait for write completion of superblocks done by write_dev_supers,
4180 * @max_mirrors same for write and wait phases.
4181 *
4182 * Return number of errors when page is not found or not marked up to
4183 * date.
4184 */
4185static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
4186{
 
4187	int i;
4188	int errors = 0;
4189	bool primary_failed = false;
4190	int ret;
4191	u64 bytenr;
4192
4193	if (max_mirrors == 0)
4194		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
4195
4196	for (i = 0; i < max_mirrors; i++) {
4197		struct page *page;
4198
4199		ret = btrfs_sb_log_location(device, i, READ, &bytenr);
4200		if (ret == -ENOENT) {
4201			break;
4202		} else if (ret < 0) {
4203			errors++;
4204			if (i == 0)
4205				primary_failed = true;
4206			continue;
4207		}
4208		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
4209		    device->commit_total_bytes)
4210			break;
4211
4212		page = find_get_page(device->bdev->bd_inode->i_mapping,
4213				     bytenr >> PAGE_SHIFT);
4214		if (!page) {
 
4215			errors++;
4216			if (i == 0)
4217				primary_failed = true;
4218			continue;
4219		}
4220		/* Page is submitted locked and unlocked once the IO completes */
4221		wait_on_page_locked(page);
4222		if (PageError(page)) {
4223			errors++;
4224			if (i == 0)
4225				primary_failed = true;
4226		}
4227
4228		/* Drop our reference */
4229		put_page(page);
4230
4231		/* Drop the reference from the writing run */
4232		put_page(page);
4233	}
4234
4235	/* log error, force error return */
4236	if (primary_failed) {
4237		btrfs_err(device->fs_info, "error writing primary super block to device %llu",
4238			  device->devid);
4239		return -1;
4240	}
4241
4242	return errors < i ? 0 : -1;
4243}
4244
4245/*
4246 * endio for the write_dev_flush, this will wake anyone waiting
4247 * for the barrier when it is done
4248 */
4249static void btrfs_end_empty_barrier(struct bio *bio)
4250{
4251	bio_uninit(bio);
4252	complete(bio->bi_private);
4253}
4254
4255/*
4256 * Submit a flush request to the device if it supports it. Error handling is
4257 * done in the waiting counterpart.
4258 */
4259static void write_dev_flush(struct btrfs_device *device)
4260{
4261	struct bio *bio = &device->flush_bio;
 
4262
4263#ifndef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4264	/*
4265	 * When a disk has write caching disabled, we skip submission of a bio
4266	 * with flush and sync requests before writing the superblock, since
4267	 * it's not needed. However when the integrity checker is enabled, this
4268	 * results in reports that there are metadata blocks referred by a
4269	 * superblock that were not properly flushed. So don't skip the bio
4270	 * submission only when the integrity checker is enabled for the sake
4271	 * of simplicity, since this is a debug tool and not meant for use in
4272	 * non-debug builds.
4273	 */
4274	if (!bdev_write_cache(device->bdev))
4275		return;
4276#endif
4277
4278	bio_init(bio, device->bdev, NULL, 0,
4279		 REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH);
4280	bio->bi_end_io = btrfs_end_empty_barrier;
 
 
4281	init_completion(&device->flush_wait);
4282	bio->bi_private = &device->flush_wait;
4283
4284	btrfsic_check_bio(bio);
4285	submit_bio(bio);
4286	set_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
4287}
4288
4289/*
4290 * If the flush bio has been submitted by write_dev_flush, wait for it.
4291 */
4292static blk_status_t wait_dev_flush(struct btrfs_device *device)
4293{
4294	struct bio *bio = &device->flush_bio;
4295
4296	if (!test_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state))
4297		return BLK_STS_OK;
4298
4299	clear_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
4300	wait_for_completion_io(&device->flush_wait);
4301
4302	return bio->bi_status;
4303}
4304
4305static int check_barrier_error(struct btrfs_fs_info *fs_info)
4306{
4307	if (!btrfs_check_rw_degradable(fs_info, NULL))
4308		return -EIO;
4309	return 0;
4310}
4311
4312/*
4313 * send an empty flush down to each device in parallel,
4314 * then wait for them
4315 */
4316static int barrier_all_devices(struct btrfs_fs_info *info)
4317{
4318	struct list_head *head;
4319	struct btrfs_device *dev;
4320	int errors_wait = 0;
4321	blk_status_t ret;
4322
4323	lockdep_assert_held(&info->fs_devices->device_list_mutex);
4324	/* send down all the barriers */
4325	head = &info->fs_devices->devices;
4326	list_for_each_entry(dev, head, dev_list) {
4327		if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
4328			continue;
4329		if (!dev->bdev)
4330			continue;
4331		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4332		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4333			continue;
4334
4335		write_dev_flush(dev);
4336		dev->last_flush_error = BLK_STS_OK;
4337	}
4338
4339	/* wait for all the barriers */
4340	list_for_each_entry(dev, head, dev_list) {
4341		if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
4342			continue;
4343		if (!dev->bdev) {
4344			errors_wait++;
4345			continue;
4346		}
4347		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4348		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4349			continue;
4350
4351		ret = wait_dev_flush(dev);
4352		if (ret) {
4353			dev->last_flush_error = ret;
4354			btrfs_dev_stat_inc_and_print(dev,
4355					BTRFS_DEV_STAT_FLUSH_ERRS);
4356			errors_wait++;
4357		}
4358	}
4359
4360	if (errors_wait) {
4361		/*
4362		 * At some point we need the status of all disks
4363		 * to arrive at the volume status. So error checking
4364		 * is being pushed to a separate loop.
4365		 */
4366		return check_barrier_error(info);
4367	}
4368	return 0;
4369}
4370
4371int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags)
4372{
4373	int raid_type;
4374	int min_tolerated = INT_MAX;
4375
4376	if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 ||
4377	    (flags & BTRFS_AVAIL_ALLOC_BIT_SINGLE))
4378		min_tolerated = min_t(int, min_tolerated,
4379				    btrfs_raid_array[BTRFS_RAID_SINGLE].
4380				    tolerated_failures);
4381
4382	for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
4383		if (raid_type == BTRFS_RAID_SINGLE)
4384			continue;
4385		if (!(flags & btrfs_raid_array[raid_type].bg_flag))
4386			continue;
4387		min_tolerated = min_t(int, min_tolerated,
4388				    btrfs_raid_array[raid_type].
4389				    tolerated_failures);
4390	}
4391
4392	if (min_tolerated == INT_MAX) {
4393		pr_warn("BTRFS: unknown raid flag: %llu", flags);
4394		min_tolerated = 0;
4395	}
4396
4397	return min_tolerated;
4398}
4399
4400int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors)
4401{
4402	struct list_head *head;
4403	struct btrfs_device *dev;
4404	struct btrfs_super_block *sb;
4405	struct btrfs_dev_item *dev_item;
4406	int ret;
4407	int do_barriers;
4408	int max_errors;
4409	int total_errors = 0;
4410	u64 flags;
4411
4412	do_barriers = !btrfs_test_opt(fs_info, NOBARRIER);
4413
4414	/*
4415	 * max_mirrors == 0 indicates we're from commit_transaction,
4416	 * not from fsync where the tree roots in fs_info have not
4417	 * been consistent on disk.
4418	 */
4419	if (max_mirrors == 0)
4420		backup_super_roots(fs_info);
4421
4422	sb = fs_info->super_for_commit;
4423	dev_item = &sb->dev_item;
4424
4425	mutex_lock(&fs_info->fs_devices->device_list_mutex);
4426	head = &fs_info->fs_devices->devices;
4427	max_errors = btrfs_super_num_devices(fs_info->super_copy) - 1;
4428
4429	if (do_barriers) {
4430		ret = barrier_all_devices(fs_info);
4431		if (ret) {
4432			mutex_unlock(
4433				&fs_info->fs_devices->device_list_mutex);
4434			btrfs_handle_fs_error(fs_info, ret,
4435					      "errors while submitting device barriers.");
4436			return ret;
4437		}
4438	}
4439
4440	list_for_each_entry(dev, head, dev_list) {
4441		if (!dev->bdev) {
4442			total_errors++;
4443			continue;
4444		}
4445		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4446		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4447			continue;
4448
4449		btrfs_set_stack_device_generation(dev_item, 0);
4450		btrfs_set_stack_device_type(dev_item, dev->type);
4451		btrfs_set_stack_device_id(dev_item, dev->devid);
4452		btrfs_set_stack_device_total_bytes(dev_item,
4453						   dev->commit_total_bytes);
4454		btrfs_set_stack_device_bytes_used(dev_item,
4455						  dev->commit_bytes_used);
4456		btrfs_set_stack_device_io_align(dev_item, dev->io_align);
4457		btrfs_set_stack_device_io_width(dev_item, dev->io_width);
4458		btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
4459		memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
4460		memcpy(dev_item->fsid, dev->fs_devices->metadata_uuid,
4461		       BTRFS_FSID_SIZE);
4462
4463		flags = btrfs_super_flags(sb);
4464		btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
4465
4466		ret = btrfs_validate_write_super(fs_info, sb);
4467		if (ret < 0) {
4468			mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4469			btrfs_handle_fs_error(fs_info, -EUCLEAN,
4470				"unexpected superblock corruption detected");
4471			return -EUCLEAN;
4472		}
4473
4474		ret = write_dev_supers(dev, sb, max_mirrors);
4475		if (ret)
4476			total_errors++;
4477	}
4478	if (total_errors > max_errors) {
4479		btrfs_err(fs_info, "%d errors while writing supers",
4480			  total_errors);
4481		mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4482
4483		/* FUA is masked off if unsupported and can't be the reason */
4484		btrfs_handle_fs_error(fs_info, -EIO,
4485				      "%d errors while writing supers",
4486				      total_errors);
4487		return -EIO;
4488	}
4489
4490	total_errors = 0;
4491	list_for_each_entry(dev, head, dev_list) {
4492		if (!dev->bdev)
4493			continue;
4494		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
4495		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
4496			continue;
4497
4498		ret = wait_dev_supers(dev, max_mirrors);
4499		if (ret)
4500			total_errors++;
4501	}
4502	mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4503	if (total_errors > max_errors) {
4504		btrfs_handle_fs_error(fs_info, -EIO,
4505				      "%d errors while writing supers",
4506				      total_errors);
4507		return -EIO;
4508	}
4509	return 0;
4510}
4511
4512/* Drop a fs root from the radix tree and free it. */
4513void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
4514				  struct btrfs_root *root)
4515{
4516	bool drop_ref = false;
4517
4518	spin_lock(&fs_info->fs_roots_radix_lock);
4519	radix_tree_delete(&fs_info->fs_roots_radix,
4520			  (unsigned long)root->root_key.objectid);
4521	if (test_and_clear_bit(BTRFS_ROOT_IN_RADIX, &root->state))
4522		drop_ref = true;
4523	spin_unlock(&fs_info->fs_roots_radix_lock);
4524
4525	if (BTRFS_FS_ERROR(fs_info)) {
4526		ASSERT(root->log_root == NULL);
 
 
 
4527		if (root->reloc_root) {
4528			btrfs_put_root(root->reloc_root);
 
 
4529			root->reloc_root = NULL;
4530		}
4531	}
4532
4533	if (drop_ref)
4534		btrfs_put_root(root);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4535}
4536
4537int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
4538{
4539	u64 root_objectid = 0;
4540	struct btrfs_root *gang[8];
4541	int i = 0;
4542	int err = 0;
4543	unsigned int ret = 0;
 
4544
4545	while (1) {
4546		spin_lock(&fs_info->fs_roots_radix_lock);
4547		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
4548					     (void **)gang, root_objectid,
4549					     ARRAY_SIZE(gang));
4550		if (!ret) {
4551			spin_unlock(&fs_info->fs_roots_radix_lock);
4552			break;
4553		}
4554		root_objectid = gang[ret - 1]->root_key.objectid + 1;
4555
4556		for (i = 0; i < ret; i++) {
4557			/* Avoid to grab roots in dead_roots */
4558			if (btrfs_root_refs(&gang[i]->root_item) == 0) {
4559				gang[i] = NULL;
4560				continue;
4561			}
4562			/* grab all the search result for later use */
4563			gang[i] = btrfs_grab_root(gang[i]);
4564		}
4565		spin_unlock(&fs_info->fs_roots_radix_lock);
4566
4567		for (i = 0; i < ret; i++) {
4568			if (!gang[i])
4569				continue;
4570			root_objectid = gang[i]->root_key.objectid;
4571			err = btrfs_orphan_cleanup(gang[i]);
4572			if (err)
4573				break;
4574			btrfs_put_root(gang[i]);
4575		}
4576		root_objectid++;
4577	}
4578
4579	/* release the uncleaned roots due to error */
4580	for (; i < ret; i++) {
4581		if (gang[i])
4582			btrfs_put_root(gang[i]);
4583	}
4584	return err;
4585}
4586
4587int btrfs_commit_super(struct btrfs_fs_info *fs_info)
4588{
4589	struct btrfs_root *root = fs_info->tree_root;
4590	struct btrfs_trans_handle *trans;
4591
4592	mutex_lock(&fs_info->cleaner_mutex);
4593	btrfs_run_delayed_iputs(fs_info);
4594	mutex_unlock(&fs_info->cleaner_mutex);
4595	wake_up_process(fs_info->cleaner_kthread);
4596
4597	/* wait until ongoing cleanup work done */
4598	down_write(&fs_info->cleanup_work_sem);
4599	up_write(&fs_info->cleanup_work_sem);
4600
4601	trans = btrfs_join_transaction(root);
4602	if (IS_ERR(trans))
4603		return PTR_ERR(trans);
4604	return btrfs_commit_transaction(trans);
4605}
4606
4607static void warn_about_uncommitted_trans(struct btrfs_fs_info *fs_info)
4608{
4609	struct btrfs_transaction *trans;
4610	struct btrfs_transaction *tmp;
4611	bool found = false;
4612
4613	if (list_empty(&fs_info->trans_list))
4614		return;
4615
4616	/*
4617	 * This function is only called at the very end of close_ctree(),
4618	 * thus no other running transaction, no need to take trans_lock.
4619	 */
4620	ASSERT(test_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags));
4621	list_for_each_entry_safe(trans, tmp, &fs_info->trans_list, list) {
4622		struct extent_state *cached = NULL;
4623		u64 dirty_bytes = 0;
4624		u64 cur = 0;
4625		u64 found_start;
4626		u64 found_end;
4627
4628		found = true;
4629		while (!find_first_extent_bit(&trans->dirty_pages, cur,
4630			&found_start, &found_end, EXTENT_DIRTY, &cached)) {
4631			dirty_bytes += found_end + 1 - found_start;
4632			cur = found_end + 1;
4633		}
4634		btrfs_warn(fs_info,
4635	"transaction %llu (with %llu dirty metadata bytes) is not committed",
4636			   trans->transid, dirty_bytes);
4637		btrfs_cleanup_one_transaction(trans, fs_info);
4638
4639		if (trans == fs_info->running_transaction)
4640			fs_info->running_transaction = NULL;
4641		list_del_init(&trans->list);
4642
4643		btrfs_put_transaction(trans);
4644		trace_btrfs_transaction_commit(fs_info);
4645	}
4646	ASSERT(!found);
4647}
4648
4649void __cold close_ctree(struct btrfs_fs_info *fs_info)
4650{
4651	int ret;
4652
4653	set_bit(BTRFS_FS_CLOSING_START, &fs_info->flags);
4654
4655	/*
4656	 * If we had UNFINISHED_DROPS we could still be processing them, so
4657	 * clear that bit and wake up relocation so it can stop.
4658	 * We must do this before stopping the block group reclaim task, because
4659	 * at btrfs_relocate_block_group() we wait for this bit, and after the
4660	 * wait we stop with -EINTR if btrfs_fs_closing() returns non-zero - we
4661	 * have just set BTRFS_FS_CLOSING_START, so btrfs_fs_closing() will
4662	 * return 1.
4663	 */
4664	btrfs_wake_unfinished_drop(fs_info);
4665
4666	/*
4667	 * We may have the reclaim task running and relocating a data block group,
4668	 * in which case it may create delayed iputs. So stop it before we park
4669	 * the cleaner kthread otherwise we can get new delayed iputs after
4670	 * parking the cleaner, and that can make the async reclaim task to hang
4671	 * if it's waiting for delayed iputs to complete, since the cleaner is
4672	 * parked and can not run delayed iputs - this will make us hang when
4673	 * trying to stop the async reclaim task.
4674	 */
4675	cancel_work_sync(&fs_info->reclaim_bgs_work);
4676	/*
4677	 * We don't want the cleaner to start new transactions, add more delayed
4678	 * iputs, etc. while we're closing. We can't use kthread_stop() yet
4679	 * because that frees the task_struct, and the transaction kthread might
4680	 * still try to wake up the cleaner.
4681	 */
4682	kthread_park(fs_info->cleaner_kthread);
4683
4684	/* wait for the qgroup rescan worker to stop */
4685	btrfs_qgroup_wait_for_completion(fs_info, false);
4686
4687	/* wait for the uuid_scan task to finish */
4688	down(&fs_info->uuid_tree_rescan_sem);
4689	/* avoid complains from lockdep et al., set sem back to initial state */
4690	up(&fs_info->uuid_tree_rescan_sem);
4691
4692	/* pause restriper - we want to resume on mount */
4693	btrfs_pause_balance(fs_info);
4694
4695	btrfs_dev_replace_suspend_for_unmount(fs_info);
4696
4697	btrfs_scrub_cancel(fs_info);
4698
4699	/* wait for any defraggers to finish */
4700	wait_event(fs_info->transaction_wait,
4701		   (atomic_read(&fs_info->defrag_running) == 0));
4702
4703	/* clear out the rbtree of defraggable inodes */
4704	btrfs_cleanup_defrag_inodes(fs_info);
4705
4706	/*
4707	 * After we parked the cleaner kthread, ordered extents may have
4708	 * completed and created new delayed iputs. If one of the async reclaim
4709	 * tasks is running and in the RUN_DELAYED_IPUTS flush state, then we
4710	 * can hang forever trying to stop it, because if a delayed iput is
4711	 * added after it ran btrfs_run_delayed_iputs() and before it called
4712	 * btrfs_wait_on_delayed_iputs(), it will hang forever since there is
4713	 * no one else to run iputs.
4714	 *
4715	 * So wait for all ongoing ordered extents to complete and then run
4716	 * delayed iputs. This works because once we reach this point no one
4717	 * can either create new ordered extents nor create delayed iputs
4718	 * through some other means.
4719	 *
4720	 * Also note that btrfs_wait_ordered_roots() is not safe here, because
4721	 * it waits for BTRFS_ORDERED_COMPLETE to be set on an ordered extent,
4722	 * but the delayed iput for the respective inode is made only when doing
4723	 * the final btrfs_put_ordered_extent() (which must happen at
4724	 * btrfs_finish_ordered_io() when we are unmounting).
4725	 */
4726	btrfs_flush_workqueue(fs_info->endio_write_workers);
4727	/* Ordered extents for free space inodes. */
4728	btrfs_flush_workqueue(fs_info->endio_freespace_worker);
4729	btrfs_run_delayed_iputs(fs_info);
4730
4731	cancel_work_sync(&fs_info->async_reclaim_work);
4732	cancel_work_sync(&fs_info->async_data_reclaim_work);
4733	cancel_work_sync(&fs_info->preempt_reclaim_work);
4734
4735	/* Cancel or finish ongoing discard work */
4736	btrfs_discard_cleanup(fs_info);
4737
4738	if (!sb_rdonly(fs_info->sb)) {
4739		/*
4740		 * The cleaner kthread is stopped, so do one final pass over
4741		 * unused block groups.
4742		 */
4743		btrfs_delete_unused_bgs(fs_info);
4744
4745		/*
4746		 * There might be existing delayed inode workers still running
4747		 * and holding an empty delayed inode item. We must wait for
4748		 * them to complete first because they can create a transaction.
4749		 * This happens when someone calls btrfs_balance_delayed_items()
4750		 * and then a transaction commit runs the same delayed nodes
4751		 * before any delayed worker has done something with the nodes.
4752		 * We must wait for any worker here and not at transaction
4753		 * commit time since that could cause a deadlock.
4754		 * This is a very rare case.
4755		 */
4756		btrfs_flush_workqueue(fs_info->delayed_workers);
4757
4758		ret = btrfs_commit_super(fs_info);
4759		if (ret)
4760			btrfs_err(fs_info, "commit super ret %d", ret);
4761	}
4762
4763	if (BTRFS_FS_ERROR(fs_info))
 
4764		btrfs_error_commit_super(fs_info);
4765
4766	kthread_stop(fs_info->transaction_kthread);
4767	kthread_stop(fs_info->cleaner_kthread);
4768
4769	ASSERT(list_empty(&fs_info->delayed_iputs));
4770	set_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags);
4771
4772	if (btrfs_check_quota_leak(fs_info)) {
4773		WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
4774		btrfs_err(fs_info, "qgroup reserved space leaked");
4775	}
4776
4777	btrfs_free_qgroup_config(fs_info);
4778	ASSERT(list_empty(&fs_info->delalloc_roots));
4779
4780	if (percpu_counter_sum(&fs_info->delalloc_bytes)) {
4781		btrfs_info(fs_info, "at unmount delalloc count %lld",
4782		       percpu_counter_sum(&fs_info->delalloc_bytes));
4783	}
4784
4785	if (percpu_counter_sum(&fs_info->ordered_bytes))
4786		btrfs_info(fs_info, "at unmount dio bytes count %lld",
4787			   percpu_counter_sum(&fs_info->ordered_bytes));
4788
4789	btrfs_sysfs_remove_mounted(fs_info);
4790	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
4791
 
 
4792	btrfs_put_block_group_cache(fs_info);
4793
4794	/*
4795	 * we must make sure there is not any read request to
4796	 * submit after we stopping all workers.
4797	 */
4798	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
4799	btrfs_stop_all_workers(fs_info);
4800
4801	/* We shouldn't have any transaction open at this point */
4802	warn_about_uncommitted_trans(fs_info);
4803
4804	clear_bit(BTRFS_FS_OPEN, &fs_info->flags);
4805	free_root_pointers(fs_info, true);
4806	btrfs_free_fs_roots(fs_info);
4807
4808	/*
4809	 * We must free the block groups after dropping the fs_roots as we could
4810	 * have had an IO error and have left over tree log blocks that aren't
4811	 * cleaned up until the fs roots are freed.  This makes the block group
4812	 * accounting appear to be wrong because there's pending reserved bytes,
4813	 * so make sure we do the block group cleanup afterwards.
4814	 */
4815	btrfs_free_block_groups(fs_info);
4816
4817	iput(fs_info->btree_inode);
4818
4819#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4820	if (btrfs_test_opt(fs_info, CHECK_INTEGRITY))
4821		btrfsic_unmount(fs_info->fs_devices);
4822#endif
4823
4824	btrfs_mapping_tree_free(&fs_info->mapping_tree);
4825	btrfs_close_devices(fs_info->fs_devices);
 
 
 
 
 
 
 
 
 
 
4826}
4827
4828int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
4829			  int atomic)
4830{
4831	int ret;
4832	struct inode *btree_inode = buf->pages[0]->mapping->host;
4833
4834	ret = extent_buffer_uptodate(buf);
4835	if (!ret)
4836		return ret;
4837
4838	ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
4839				    parent_transid, atomic);
4840	if (ret == -EAGAIN)
4841		return ret;
4842	return !ret;
4843}
4844
4845void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
4846{
4847	struct btrfs_fs_info *fs_info = buf->fs_info;
 
4848	u64 transid = btrfs_header_generation(buf);
4849	int was_dirty;
4850
4851#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4852	/*
4853	 * This is a fast path so only do this check if we have sanity tests
4854	 * enabled.  Normal people shouldn't be using unmapped buffers as dirty
4855	 * outside of the sanity tests.
4856	 */
4857	if (unlikely(test_bit(EXTENT_BUFFER_UNMAPPED, &buf->bflags)))
4858		return;
4859#endif
4860	btrfs_assert_tree_write_locked(buf);
 
 
4861	if (transid != fs_info->generation)
4862		WARN(1, KERN_CRIT "btrfs transid mismatch buffer %llu, found %llu running %llu\n",
4863			buf->start, transid, fs_info->generation);
4864	was_dirty = set_extent_buffer_dirty(buf);
4865	if (!was_dirty)
4866		percpu_counter_add_batch(&fs_info->dirty_metadata_bytes,
4867					 buf->len,
4868					 fs_info->dirty_metadata_batch);
4869#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4870	/*
4871	 * Since btrfs_mark_buffer_dirty() can be called with item pointer set
4872	 * but item data not updated.
4873	 * So here we should only check item pointers, not item data.
4874	 */
4875	if (btrfs_header_level(buf) == 0 &&
4876	    btrfs_check_leaf_relaxed(buf)) {
4877		btrfs_print_leaf(buf);
4878		ASSERT(0);
4879	}
4880#endif
4881}
4882
4883static void __btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info,
4884					int flush_delayed)
4885{
4886	/*
4887	 * looks as though older kernels can get into trouble with
4888	 * this code, they end up stuck in balance_dirty_pages forever
4889	 */
4890	int ret;
4891
4892	if (current->flags & PF_MEMALLOC)
4893		return;
4894
4895	if (flush_delayed)
4896		btrfs_balance_delayed_items(fs_info);
4897
4898	ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
4899				     BTRFS_DIRTY_METADATA_THRESH,
4900				     fs_info->dirty_metadata_batch);
4901	if (ret > 0) {
4902		balance_dirty_pages_ratelimited(fs_info->btree_inode->i_mapping);
4903	}
4904}
4905
4906void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info)
4907{
4908	__btrfs_btree_balance_dirty(fs_info, 1);
4909}
4910
4911void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info)
4912{
4913	__btrfs_btree_balance_dirty(fs_info, 0);
4914}
4915
 
 
 
 
 
 
 
4916static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info)
4917{
4918	/* cleanup FS via transaction */
4919	btrfs_cleanup_transaction(fs_info);
4920
4921	mutex_lock(&fs_info->cleaner_mutex);
4922	btrfs_run_delayed_iputs(fs_info);
4923	mutex_unlock(&fs_info->cleaner_mutex);
4924
4925	down_write(&fs_info->cleanup_work_sem);
4926	up_write(&fs_info->cleanup_work_sem);
4927}
4928
4929static void btrfs_drop_all_logs(struct btrfs_fs_info *fs_info)
4930{
4931	struct btrfs_root *gang[8];
4932	u64 root_objectid = 0;
4933	int ret;
4934
4935	spin_lock(&fs_info->fs_roots_radix_lock);
4936	while ((ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
4937					     (void **)gang, root_objectid,
4938					     ARRAY_SIZE(gang))) != 0) {
4939		int i;
4940
4941		for (i = 0; i < ret; i++)
4942			gang[i] = btrfs_grab_root(gang[i]);
4943		spin_unlock(&fs_info->fs_roots_radix_lock);
4944
4945		for (i = 0; i < ret; i++) {
4946			if (!gang[i])
4947				continue;
4948			root_objectid = gang[i]->root_key.objectid;
4949			btrfs_free_log(NULL, gang[i]);
4950			btrfs_put_root(gang[i]);
4951		}
4952		root_objectid++;
4953		spin_lock(&fs_info->fs_roots_radix_lock);
4954	}
4955	spin_unlock(&fs_info->fs_roots_radix_lock);
4956	btrfs_free_log_root_tree(NULL, fs_info);
4957}
4958
4959static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
4960{
4961	struct btrfs_ordered_extent *ordered;
4962
4963	spin_lock(&root->ordered_extent_lock);
4964	/*
4965	 * This will just short circuit the ordered completion stuff which will
4966	 * make sure the ordered extent gets properly cleaned up.
4967	 */
4968	list_for_each_entry(ordered, &root->ordered_extents,
4969			    root_extent_list)
4970		set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
4971	spin_unlock(&root->ordered_extent_lock);
4972}
4973
4974static void btrfs_destroy_all_ordered_extents(struct btrfs_fs_info *fs_info)
4975{
4976	struct btrfs_root *root;
4977	struct list_head splice;
4978
4979	INIT_LIST_HEAD(&splice);
4980
4981	spin_lock(&fs_info->ordered_root_lock);
4982	list_splice_init(&fs_info->ordered_roots, &splice);
4983	while (!list_empty(&splice)) {
4984		root = list_first_entry(&splice, struct btrfs_root,
4985					ordered_root);
4986		list_move_tail(&root->ordered_root,
4987			       &fs_info->ordered_roots);
4988
4989		spin_unlock(&fs_info->ordered_root_lock);
4990		btrfs_destroy_ordered_extents(root);
4991
4992		cond_resched();
4993		spin_lock(&fs_info->ordered_root_lock);
4994	}
4995	spin_unlock(&fs_info->ordered_root_lock);
4996
4997	/*
4998	 * We need this here because if we've been flipped read-only we won't
4999	 * get sync() from the umount, so we need to make sure any ordered
5000	 * extents that haven't had their dirty pages IO start writeout yet
5001	 * actually get run and error out properly.
5002	 */
5003	btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
5004}
5005
5006static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
5007				      struct btrfs_fs_info *fs_info)
5008{
5009	struct rb_node *node;
5010	struct btrfs_delayed_ref_root *delayed_refs;
5011	struct btrfs_delayed_ref_node *ref;
5012	int ret = 0;
5013
5014	delayed_refs = &trans->delayed_refs;
5015
5016	spin_lock(&delayed_refs->lock);
5017	if (atomic_read(&delayed_refs->num_entries) == 0) {
5018		spin_unlock(&delayed_refs->lock);
5019		btrfs_debug(fs_info, "delayed_refs has NO entry");
5020		return ret;
5021	}
5022
5023	while ((node = rb_first_cached(&delayed_refs->href_root)) != NULL) {
5024		struct btrfs_delayed_ref_head *head;
5025		struct rb_node *n;
5026		bool pin_bytes = false;
5027
5028		head = rb_entry(node, struct btrfs_delayed_ref_head,
5029				href_node);
5030		if (btrfs_delayed_ref_lock(delayed_refs, head))
5031			continue;
5032
5033		spin_lock(&head->lock);
5034		while ((n = rb_first_cached(&head->ref_tree)) != NULL) {
5035			ref = rb_entry(n, struct btrfs_delayed_ref_node,
5036				       ref_node);
5037			ref->in_tree = 0;
5038			rb_erase_cached(&ref->ref_node, &head->ref_tree);
5039			RB_CLEAR_NODE(&ref->ref_node);
5040			if (!list_empty(&ref->add_list))
5041				list_del(&ref->add_list);
5042			atomic_dec(&delayed_refs->num_entries);
5043			btrfs_put_delayed_ref(ref);
5044		}
5045		if (head->must_insert_reserved)
5046			pin_bytes = true;
5047		btrfs_free_delayed_extent_op(head->extent_op);
5048		btrfs_delete_ref_head(delayed_refs, head);
5049		spin_unlock(&head->lock);
5050		spin_unlock(&delayed_refs->lock);
5051		mutex_unlock(&head->mutex);
5052
5053		if (pin_bytes) {
5054			struct btrfs_block_group *cache;
5055
5056			cache = btrfs_lookup_block_group(fs_info, head->bytenr);
5057			BUG_ON(!cache);
5058
5059			spin_lock(&cache->space_info->lock);
5060			spin_lock(&cache->lock);
5061			cache->pinned += head->num_bytes;
5062			btrfs_space_info_update_bytes_pinned(fs_info,
5063				cache->space_info, head->num_bytes);
5064			cache->reserved -= head->num_bytes;
5065			cache->space_info->bytes_reserved -= head->num_bytes;
5066			spin_unlock(&cache->lock);
5067			spin_unlock(&cache->space_info->lock);
5068
5069			btrfs_put_block_group(cache);
5070
5071			btrfs_error_unpin_extent_range(fs_info, head->bytenr,
5072				head->bytenr + head->num_bytes - 1);
5073		}
5074		btrfs_cleanup_ref_head_accounting(fs_info, delayed_refs, head);
5075		btrfs_put_delayed_ref_head(head);
5076		cond_resched();
5077		spin_lock(&delayed_refs->lock);
5078	}
5079	btrfs_qgroup_destroy_extent_records(trans);
5080
5081	spin_unlock(&delayed_refs->lock);
5082
5083	return ret;
5084}
5085
5086static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
5087{
5088	struct btrfs_inode *btrfs_inode;
5089	struct list_head splice;
5090
5091	INIT_LIST_HEAD(&splice);
5092
5093	spin_lock(&root->delalloc_lock);
5094	list_splice_init(&root->delalloc_inodes, &splice);
5095
5096	while (!list_empty(&splice)) {
5097		struct inode *inode = NULL;
5098		btrfs_inode = list_first_entry(&splice, struct btrfs_inode,
5099					       delalloc_inodes);
5100		__btrfs_del_delalloc_inode(root, btrfs_inode);
5101		spin_unlock(&root->delalloc_lock);
5102
5103		/*
5104		 * Make sure we get a live inode and that it'll not disappear
5105		 * meanwhile.
5106		 */
5107		inode = igrab(&btrfs_inode->vfs_inode);
5108		if (inode) {
5109			invalidate_inode_pages2(inode->i_mapping);
5110			iput(inode);
5111		}
5112		spin_lock(&root->delalloc_lock);
5113	}
5114	spin_unlock(&root->delalloc_lock);
5115}
5116
5117static void btrfs_destroy_all_delalloc_inodes(struct btrfs_fs_info *fs_info)
5118{
5119	struct btrfs_root *root;
5120	struct list_head splice;
5121
5122	INIT_LIST_HEAD(&splice);
5123
5124	spin_lock(&fs_info->delalloc_root_lock);
5125	list_splice_init(&fs_info->delalloc_roots, &splice);
5126	while (!list_empty(&splice)) {
5127		root = list_first_entry(&splice, struct btrfs_root,
5128					 delalloc_root);
5129		root = btrfs_grab_root(root);
5130		BUG_ON(!root);
5131		spin_unlock(&fs_info->delalloc_root_lock);
5132
5133		btrfs_destroy_delalloc_inodes(root);
5134		btrfs_put_root(root);
5135
5136		spin_lock(&fs_info->delalloc_root_lock);
5137	}
5138	spin_unlock(&fs_info->delalloc_root_lock);
5139}
5140
5141static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
5142					struct extent_io_tree *dirty_pages,
5143					int mark)
5144{
5145	int ret;
5146	struct extent_buffer *eb;
5147	u64 start = 0;
5148	u64 end;
5149
5150	while (1) {
5151		ret = find_first_extent_bit(dirty_pages, start, &start, &end,
5152					    mark, NULL);
5153		if (ret)
5154			break;
5155
5156		clear_extent_bits(dirty_pages, start, end, mark);
5157		while (start <= end) {
5158			eb = find_extent_buffer(fs_info, start);
5159			start += fs_info->nodesize;
5160			if (!eb)
5161				continue;
5162			wait_on_extent_buffer_writeback(eb);
5163
5164			if (test_and_clear_bit(EXTENT_BUFFER_DIRTY,
5165					       &eb->bflags))
5166				clear_extent_buffer_dirty(eb);
5167			free_extent_buffer_stale(eb);
5168		}
5169	}
5170
5171	return ret;
5172}
5173
5174static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
5175				       struct extent_io_tree *unpin)
5176{
 
5177	u64 start;
5178	u64 end;
5179	int ret;
 
5180
 
 
5181	while (1) {
5182		struct extent_state *cached_state = NULL;
5183
5184		/*
5185		 * The btrfs_finish_extent_commit() may get the same range as
5186		 * ours between find_first_extent_bit and clear_extent_dirty.
5187		 * Hence, hold the unused_bg_unpin_mutex to avoid double unpin
5188		 * the same extent range.
5189		 */
5190		mutex_lock(&fs_info->unused_bg_unpin_mutex);
5191		ret = find_first_extent_bit(unpin, 0, &start, &end,
5192					    EXTENT_DIRTY, &cached_state);
5193		if (ret) {
5194			mutex_unlock(&fs_info->unused_bg_unpin_mutex);
5195			break;
5196		}
5197
5198		clear_extent_dirty(unpin, start, end, &cached_state);
5199		free_extent_state(cached_state);
5200		btrfs_error_unpin_extent_range(fs_info, start, end);
5201		mutex_unlock(&fs_info->unused_bg_unpin_mutex);
5202		cond_resched();
5203	}
5204
 
 
 
 
 
 
 
 
 
5205	return 0;
5206}
5207
5208static void btrfs_cleanup_bg_io(struct btrfs_block_group *cache)
5209{
5210	struct inode *inode;
5211
5212	inode = cache->io_ctl.inode;
5213	if (inode) {
5214		invalidate_inode_pages2(inode->i_mapping);
5215		BTRFS_I(inode)->generation = 0;
5216		cache->io_ctl.inode = NULL;
5217		iput(inode);
5218	}
5219	ASSERT(cache->io_ctl.pages == NULL);
5220	btrfs_put_block_group(cache);
5221}
5222
5223void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *cur_trans,
5224			     struct btrfs_fs_info *fs_info)
5225{
5226	struct btrfs_block_group *cache;
5227
5228	spin_lock(&cur_trans->dirty_bgs_lock);
5229	while (!list_empty(&cur_trans->dirty_bgs)) {
5230		cache = list_first_entry(&cur_trans->dirty_bgs,
5231					 struct btrfs_block_group,
5232					 dirty_list);
5233
5234		if (!list_empty(&cache->io_list)) {
5235			spin_unlock(&cur_trans->dirty_bgs_lock);
5236			list_del_init(&cache->io_list);
5237			btrfs_cleanup_bg_io(cache);
5238			spin_lock(&cur_trans->dirty_bgs_lock);
5239		}
5240
5241		list_del_init(&cache->dirty_list);
5242		spin_lock(&cache->lock);
5243		cache->disk_cache_state = BTRFS_DC_ERROR;
5244		spin_unlock(&cache->lock);
5245
5246		spin_unlock(&cur_trans->dirty_bgs_lock);
5247		btrfs_put_block_group(cache);
5248		btrfs_delayed_refs_rsv_release(fs_info, 1);
5249		spin_lock(&cur_trans->dirty_bgs_lock);
5250	}
5251	spin_unlock(&cur_trans->dirty_bgs_lock);
5252
5253	/*
5254	 * Refer to the definition of io_bgs member for details why it's safe
5255	 * to use it without any locking
5256	 */
5257	while (!list_empty(&cur_trans->io_bgs)) {
5258		cache = list_first_entry(&cur_trans->io_bgs,
5259					 struct btrfs_block_group,
5260					 io_list);
5261
5262		list_del_init(&cache->io_list);
5263		spin_lock(&cache->lock);
5264		cache->disk_cache_state = BTRFS_DC_ERROR;
5265		spin_unlock(&cache->lock);
5266		btrfs_cleanup_bg_io(cache);
5267	}
5268}
5269
5270void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
5271				   struct btrfs_fs_info *fs_info)
5272{
5273	struct btrfs_device *dev, *tmp;
5274
5275	btrfs_cleanup_dirty_bgs(cur_trans, fs_info);
5276	ASSERT(list_empty(&cur_trans->dirty_bgs));
5277	ASSERT(list_empty(&cur_trans->io_bgs));
5278
5279	list_for_each_entry_safe(dev, tmp, &cur_trans->dev_update_list,
5280				 post_commit_list) {
5281		list_del_init(&dev->post_commit_list);
5282	}
5283
5284	btrfs_destroy_delayed_refs(cur_trans, fs_info);
5285
5286	cur_trans->state = TRANS_STATE_COMMIT_START;
5287	wake_up(&fs_info->transaction_blocked_wait);
5288
5289	cur_trans->state = TRANS_STATE_UNBLOCKED;
5290	wake_up(&fs_info->transaction_wait);
5291
5292	btrfs_destroy_delayed_inodes(fs_info);
 
5293
5294	btrfs_destroy_marked_extents(fs_info, &cur_trans->dirty_pages,
5295				     EXTENT_DIRTY);
5296	btrfs_destroy_pinned_extent(fs_info, &cur_trans->pinned_extents);
5297
5298	btrfs_free_redirty_list(cur_trans);
5299
5300	cur_trans->state =TRANS_STATE_COMPLETED;
5301	wake_up(&cur_trans->commit_wait);
5302}
5303
5304static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info)
5305{
5306	struct btrfs_transaction *t;
5307
5308	mutex_lock(&fs_info->transaction_kthread_mutex);
5309
5310	spin_lock(&fs_info->trans_lock);
5311	while (!list_empty(&fs_info->trans_list)) {
5312		t = list_first_entry(&fs_info->trans_list,
5313				     struct btrfs_transaction, list);
5314		if (t->state >= TRANS_STATE_COMMIT_START) {
5315			refcount_inc(&t->use_count);
5316			spin_unlock(&fs_info->trans_lock);
5317			btrfs_wait_for_commit(fs_info, t->transid);
5318			btrfs_put_transaction(t);
5319			spin_lock(&fs_info->trans_lock);
5320			continue;
5321		}
5322		if (t == fs_info->running_transaction) {
5323			t->state = TRANS_STATE_COMMIT_DOING;
5324			spin_unlock(&fs_info->trans_lock);
5325			/*
5326			 * We wait for 0 num_writers since we don't hold a trans
5327			 * handle open currently for this transaction.
5328			 */
5329			wait_event(t->writer_wait,
5330				   atomic_read(&t->num_writers) == 0);
5331		} else {
5332			spin_unlock(&fs_info->trans_lock);
5333		}
5334		btrfs_cleanup_one_transaction(t, fs_info);
5335
5336		spin_lock(&fs_info->trans_lock);
5337		if (t == fs_info->running_transaction)
5338			fs_info->running_transaction = NULL;
5339		list_del_init(&t->list);
5340		spin_unlock(&fs_info->trans_lock);
5341
5342		btrfs_put_transaction(t);
5343		trace_btrfs_transaction_commit(fs_info);
5344		spin_lock(&fs_info->trans_lock);
5345	}
5346	spin_unlock(&fs_info->trans_lock);
5347	btrfs_destroy_all_ordered_extents(fs_info);
5348	btrfs_destroy_delayed_inodes(fs_info);
5349	btrfs_assert_delayed_root_empty(fs_info);
 
5350	btrfs_destroy_all_delalloc_inodes(fs_info);
5351	btrfs_drop_all_logs(fs_info);
5352	mutex_unlock(&fs_info->transaction_kthread_mutex);
5353
5354	return 0;
5355}
5356
5357int btrfs_init_root_free_objectid(struct btrfs_root *root)
5358{
5359	struct btrfs_path *path;
5360	int ret;
5361	struct extent_buffer *l;
5362	struct btrfs_key search_key;
5363	struct btrfs_key found_key;
5364	int slot;
5365
5366	path = btrfs_alloc_path();
5367	if (!path)
5368		return -ENOMEM;
5369
5370	search_key.objectid = BTRFS_LAST_FREE_OBJECTID;
5371	search_key.type = -1;
5372	search_key.offset = (u64)-1;
5373	ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
5374	if (ret < 0)
5375		goto error;
5376	BUG_ON(ret == 0); /* Corruption */
5377	if (path->slots[0] > 0) {
5378		slot = path->slots[0] - 1;
5379		l = path->nodes[0];
5380		btrfs_item_key_to_cpu(l, &found_key, slot);
5381		root->free_objectid = max_t(u64, found_key.objectid + 1,
5382					    BTRFS_FIRST_FREE_OBJECTID);
5383	} else {
5384		root->free_objectid = BTRFS_FIRST_FREE_OBJECTID;
5385	}
5386	ret = 0;
5387error:
5388	btrfs_free_path(path);
5389	return ret;
5390}
5391
5392int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid)
5393{
5394	int ret;
5395	mutex_lock(&root->objectid_mutex);
5396
5397	if (unlikely(root->free_objectid >= BTRFS_LAST_FREE_OBJECTID)) {
5398		btrfs_warn(root->fs_info,
5399			   "the objectid of root %llu reaches its highest value",
5400			   root->root_key.objectid);
5401		ret = -ENOSPC;
5402		goto out;
5403	}
5404
5405	*objectid = root->free_objectid++;
5406	ret = 0;
5407out:
5408	mutex_unlock(&root->objectid_mutex);
5409	return ret;
5410}