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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};
v3.5.6
 
   1/*
   2 * Copyright (C) 2007 Oracle.  All rights reserved.
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of the GNU General Public
   6 * License v2 as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful,
   9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11 * General Public License for more details.
  12 *
  13 * You should have received a copy of the GNU General Public
  14 * License along with this program; if not, write to the
  15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16 * Boston, MA 021110-1307, USA.
  17 */
  18
  19#include <linux/fs.h>
  20#include <linux/blkdev.h>
  21#include <linux/scatterlist.h>
  22#include <linux/swap.h>
  23#include <linux/radix-tree.h>
  24#include <linux/writeback.h>
  25#include <linux/buffer_head.h>
  26#include <linux/workqueue.h>
  27#include <linux/kthread.h>
  28#include <linux/freezer.h>
  29#include <linux/crc32c.h>
  30#include <linux/slab.h>
  31#include <linux/migrate.h>
  32#include <linux/ratelimit.h>
 
 
 
 
 
  33#include <asm/unaligned.h>
  34#include "compat.h"
  35#include "ctree.h"
  36#include "disk-io.h"
  37#include "transaction.h"
  38#include "btrfs_inode.h"
  39#include "volumes.h"
  40#include "print-tree.h"
  41#include "async-thread.h"
  42#include "locking.h"
  43#include "tree-log.h"
  44#include "free-space-cache.h"
 
  45#include "inode-map.h"
  46#include "check-integrity.h"
  47#include "rcu-string.h"
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  48
  49static struct extent_io_ops btree_extent_io_ops;
  50static void end_workqueue_fn(struct btrfs_work *work);
  51static void free_fs_root(struct btrfs_root *root);
  52static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
  53				    int read_only);
  54static void btrfs_destroy_ordered_operations(struct btrfs_root *root);
  55static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
  56static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
  57				      struct btrfs_root *root);
  58static void btrfs_destroy_pending_snapshots(struct btrfs_transaction *t);
  59static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
  60static int btrfs_destroy_marked_extents(struct btrfs_root *root,
  61					struct extent_io_tree *dirty_pages,
  62					int mark);
  63static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
  64				       struct extent_io_tree *pinned_extents);
 
 
  65
  66/*
  67 * end_io_wq structs are used to do processing in task context when an IO is
  68 * 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 end_io_wq {
  72	struct bio *bio;
  73	bio_end_io_t *end_io;
  74	void *private;
  75	struct btrfs_fs_info *info;
  76	int error;
  77	int metadata;
  78	struct list_head list;
  79	struct btrfs_work work;
  80};
  81
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  82/*
  83 * async submit bios are used to offload expensive checksumming
  84 * onto the worker threads.  They checksum file and metadata bios
  85 * just before they are sent down the IO stack.
  86 */
  87struct async_submit_bio {
  88	struct inode *inode;
  89	struct bio *bio;
  90	struct list_head list;
  91	extent_submit_bio_hook_t *submit_bio_start;
  92	extent_submit_bio_hook_t *submit_bio_done;
  93	int rw;
  94	int mirror_num;
  95	unsigned long bio_flags;
  96	/*
  97	 * bio_offset is optional, can be used if the pages in the bio
  98	 * can't tell us where in the file the bio should go
  99	 */
 100	u64 bio_offset;
 101	struct btrfs_work work;
 102	int error;
 103};
 104
 105/*
 106 * Lockdep class keys for extent_buffer->lock's in this root.  For a given
 107 * eb, the lockdep key is determined by the btrfs_root it belongs to and
 108 * the level the eb occupies in the tree.
 109 *
 110 * Different roots are used for different purposes and may nest inside each
 111 * other and they require separate keysets.  As lockdep keys should be
 112 * static, assign keysets according to the purpose of the root as indicated
 113 * by btrfs_root->objectid.  This ensures that all special purpose roots
 114 * have separate keysets.
 115 *
 116 * Lock-nesting across peer nodes is always done with the immediate parent
 117 * node locked thus preventing deadlock.  As lockdep doesn't know this, use
 118 * subclass to avoid triggering lockdep warning in such cases.
 119 *
 120 * The key is set by the readpage_end_io_hook after the buffer has passed
 121 * csum validation but before the pages are unlocked.  It is also set by
 122 * btrfs_init_new_buffer on freshly allocated blocks.
 123 *
 124 * We also add a check to make sure the highest level of the tree is the
 125 * same as our lockdep setup here.  If BTRFS_MAX_LEVEL changes, this code
 126 * needs update as well.
 127 */
 128#ifdef CONFIG_DEBUG_LOCK_ALLOC
 129# if BTRFS_MAX_LEVEL != 8
 130#  error
 131# endif
 132
 133static struct btrfs_lockdep_keyset {
 134	u64			id;		/* root objectid */
 135	const char		*name_stem;	/* lock name stem */
 136	char			names[BTRFS_MAX_LEVEL + 1][20];
 137	struct lock_class_key	keys[BTRFS_MAX_LEVEL + 1];
 138} btrfs_lockdep_keysets[] = {
 139	{ .id = BTRFS_ROOT_TREE_OBJECTID,	.name_stem = "root"	},
 140	{ .id = BTRFS_EXTENT_TREE_OBJECTID,	.name_stem = "extent"	},
 141	{ .id = BTRFS_CHUNK_TREE_OBJECTID,	.name_stem = "chunk"	},
 142	{ .id = BTRFS_DEV_TREE_OBJECTID,	.name_stem = "dev"	},
 143	{ .id = BTRFS_FS_TREE_OBJECTID,		.name_stem = "fs"	},
 144	{ .id = BTRFS_CSUM_TREE_OBJECTID,	.name_stem = "csum"	},
 145	{ .id = BTRFS_ORPHAN_OBJECTID,		.name_stem = "orphan"	},
 146	{ .id = BTRFS_TREE_LOG_OBJECTID,	.name_stem = "log"	},
 147	{ .id = BTRFS_TREE_RELOC_OBJECTID,	.name_stem = "treloc"	},
 148	{ .id = BTRFS_DATA_RELOC_TREE_OBJECTID,	.name_stem = "dreloc"	},
 
 
 149	{ .id = 0,				.name_stem = "tree"	},
 150};
 151
 152void __init btrfs_init_lockdep(void)
 153{
 154	int i, j;
 155
 156	/* initialize lockdep class names */
 157	for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) {
 158		struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i];
 159
 160		for (j = 0; j < ARRAY_SIZE(ks->names); j++)
 161			snprintf(ks->names[j], sizeof(ks->names[j]),
 162				 "btrfs-%s-%02d", ks->name_stem, j);
 163	}
 164}
 165
 166void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
 167				    int level)
 168{
 169	struct btrfs_lockdep_keyset *ks;
 170
 171	BUG_ON(level >= ARRAY_SIZE(ks->keys));
 172
 173	/* find the matching keyset, id 0 is the default entry */
 174	for (ks = btrfs_lockdep_keysets; ks->id; ks++)
 175		if (ks->id == objectid)
 176			break;
 177
 178	lockdep_set_class_and_name(&eb->lock,
 179				   &ks->keys[level], ks->names[level]);
 180}
 181
 182#endif
 183
 184/*
 185 * extents on the btree inode are pretty simple, there's one extent
 186 * that covers the entire device
 187 */
 188static struct extent_map *btree_get_extent(struct inode *inode,
 189		struct page *page, size_t pg_offset, u64 start, u64 len,
 190		int create)
 191{
 192	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 
 193	struct extent_map *em;
 194	int ret;
 195
 196	read_lock(&em_tree->lock);
 197	em = lookup_extent_mapping(em_tree, start, len);
 198	if (em) {
 199		em->bdev =
 200			BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
 201		read_unlock(&em_tree->lock);
 202		goto out;
 203	}
 204	read_unlock(&em_tree->lock);
 205
 206	em = alloc_extent_map();
 207	if (!em) {
 208		em = ERR_PTR(-ENOMEM);
 209		goto out;
 210	}
 211	em->start = 0;
 212	em->len = (u64)-1;
 213	em->block_len = (u64)-1;
 214	em->block_start = 0;
 215	em->bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
 216
 217	write_lock(&em_tree->lock);
 218	ret = add_extent_mapping(em_tree, em);
 219	if (ret == -EEXIST) {
 220		u64 failed_start = em->start;
 221		u64 failed_len = em->len;
 222
 223		free_extent_map(em);
 224		em = lookup_extent_mapping(em_tree, start, len);
 225		if (em) {
 226			ret = 0;
 227		} else {
 228			em = lookup_extent_mapping(em_tree, failed_start,
 229						   failed_len);
 230			ret = -EIO;
 231		}
 232	} else if (ret) {
 233		free_extent_map(em);
 234		em = NULL;
 235	}
 236	write_unlock(&em_tree->lock);
 237
 238	if (ret)
 239		em = ERR_PTR(ret);
 240out:
 241	return em;
 242}
 243
 244u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
 245{
 246	return crc32c(seed, data, len);
 247}
 248
 249void btrfs_csum_final(u32 crc, char *result)
 250{
 251	put_unaligned_le32(~crc, result);
 252}
 253
 254/*
 255 * compute the csum for a btree block, and either verify it or write it
 256 * into the csum field of the block.
 
 257 */
 258static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 259			   int verify)
 260{
 261	u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
 262	char *result = NULL;
 263	unsigned long len;
 264	unsigned long cur_len;
 265	unsigned long offset = BTRFS_CSUM_SIZE;
 266	char *kaddr;
 267	unsigned long map_start;
 268	unsigned long map_len;
 269	int err;
 270	u32 crc = ~(u32)0;
 271	unsigned long inline_result;
 
 272
 273	len = buf->len - offset;
 
 274	while (len > 0) {
 
 
 
 
 
 
 275		err = map_private_extent_buffer(buf, offset, 32,
 276					&kaddr, &map_start, &map_len);
 277		if (err)
 278			return 1;
 279		cur_len = min(len, map_len - (offset - map_start));
 280		crc = btrfs_csum_data(root, kaddr + offset - map_start,
 281				      crc, cur_len);
 282		len -= cur_len;
 283		offset += cur_len;
 284	}
 285	if (csum_size > sizeof(inline_result)) {
 286		result = kzalloc(csum_size * sizeof(char), GFP_NOFS);
 287		if (!result)
 288			return 1;
 289	} else {
 290		result = (char *)&inline_result;
 291	}
 292
 293	btrfs_csum_final(crc, result);
 294
 295	if (verify) {
 296		if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
 297			u32 val;
 298			u32 found = 0;
 299			memcpy(&found, result, csum_size);
 300
 301			read_extent_buffer(buf, &val, 0, csum_size);
 302			printk_ratelimited(KERN_INFO "btrfs: %s checksum verify "
 303				       "failed on %llu wanted %X found %X "
 304				       "level %d\n",
 305				       root->fs_info->sb->s_id,
 306				       (unsigned long long)buf->start, val, found,
 307				       btrfs_header_level(buf));
 308			if (result != (char *)&inline_result)
 309				kfree(result);
 310			return 1;
 311		}
 312	} else {
 313		write_extent_buffer(buf, result, 0, csum_size);
 314	}
 315	if (result != (char *)&inline_result)
 316		kfree(result);
 317	return 0;
 318}
 319
 320/*
 321 * we can't consider a given block up to date unless the transid of the
 322 * block matches the transid in the parent node's pointer.  This is how we
 323 * detect blocks that either didn't get written at all or got written
 324 * in the wrong place.
 325 */
 326static int verify_parent_transid(struct extent_io_tree *io_tree,
 327				 struct extent_buffer *eb, u64 parent_transid,
 328				 int atomic)
 329{
 330	struct extent_state *cached_state = NULL;
 331	int ret;
 
 332
 333	if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 334		return 0;
 335
 336	if (atomic)
 337		return -EAGAIN;
 338
 
 
 
 
 
 339	lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
 340			 0, &cached_state);
 341	if (extent_buffer_uptodate(eb) &&
 342	    btrfs_header_generation(eb) == parent_transid) {
 343		ret = 0;
 344		goto out;
 345	}
 346	printk_ratelimited("parent transid verify failed on %llu wanted %llu "
 347		       "found %llu\n",
 348		       (unsigned long long)eb->start,
 349		       (unsigned long long)parent_transid,
 350		       (unsigned long long)btrfs_header_generation(eb));
 351	ret = 1;
 352	clear_extent_buffer_uptodate(eb);
 
 
 
 
 
 
 
 
 
 
 353out:
 354	unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
 355			     &cached_state, GFP_NOFS);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 356	return ret;
 357}
 358
 359/*
 360 * helper to read a given tree block, doing retries as required when
 361 * the checksums don't match and we have alternate mirrors to try.
 
 
 
 
 362 */
 363static int btree_read_extent_buffer_pages(struct btrfs_root *root,
 364					  struct extent_buffer *eb,
 365					  u64 start, u64 parent_transid)
 366{
 
 367	struct extent_io_tree *io_tree;
 368	int failed = 0;
 369	int ret;
 370	int num_copies = 0;
 371	int mirror_num = 0;
 372	int failed_mirror = 0;
 373
 374	clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 375	io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
 376	while (1) {
 377		ret = read_extent_buffer_pages(io_tree, eb, start,
 378					       WAIT_COMPLETE,
 379					       btree_get_extent, mirror_num);
 380		if (!ret && !verify_parent_transid(io_tree, eb,
 381						   parent_transid, 0))
 382			break;
 383
 384		/*
 385		 * This buffer's crc is fine, but its contents are corrupted, so
 386		 * there is no reason to read the other copies, they won't be
 387		 * any less wrong.
 388		 */
 389		if (test_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags))
 390			break;
 391
 392		num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
 393					      eb->start, eb->len);
 394		if (num_copies == 1)
 395			break;
 396
 397		if (!failed_mirror) {
 398			failed = 1;
 399			failed_mirror = eb->read_mirror;
 400		}
 401
 402		mirror_num++;
 403		if (mirror_num == failed_mirror)
 404			mirror_num++;
 405
 406		if (mirror_num > num_copies)
 407			break;
 408	}
 409
 410	if (failed && !ret)
 411		repair_eb_io_failure(root, eb, failed_mirror);
 412
 413	return ret;
 414}
 415
 416/*
 417 * checksum a dirty tree block before IO.  This has extra checks to make sure
 418 * we only fill in the checksum field in the first page of a multi-page block
 419 */
 420
 421static int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
 422{
 423	struct extent_io_tree *tree;
 424	u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
 425	u64 found_start;
 
 
 426	struct extent_buffer *eb;
 427
 428	tree = &BTRFS_I(page->mapping->host)->io_tree;
 429
 430	eb = (struct extent_buffer *)page->private;
 431	if (page != eb->pages[0])
 432		return 0;
 
 433	found_start = btrfs_header_bytenr(eb);
 434	if (found_start != start) {
 435		WARN_ON(1);
 436		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 437	}
 438	if (eb->pages[0] != page) {
 439		WARN_ON(1);
 440		return 0;
 441	}
 442	if (!PageUptodate(page)) {
 443		WARN_ON(1);
 444		return 0;
 445	}
 446	csum_tree_block(root, eb, 0);
 447	return 0;
 448}
 449
 450static int check_tree_block_fsid(struct btrfs_root *root,
 451				 struct extent_buffer *eb)
 452{
 453	struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
 454	u8 fsid[BTRFS_UUID_SIZE];
 
 455	int ret = 1;
 456
 457	read_extent_buffer(eb, fsid, (unsigned long)btrfs_header_fsid(eb),
 458			   BTRFS_FSID_SIZE);
 459	while (fs_devices) {
 460		if (!memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE)) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 461			ret = 0;
 462			break;
 463		}
 464		fs_devices = fs_devices->seed;
 465	}
 466	return ret;
 467}
 468
 469#define CORRUPT(reason, eb, root, slot)				\
 470	printk(KERN_CRIT "btrfs: corrupt leaf, %s: block=%llu,"	\
 471	       "root=%llu, slot=%d\n", reason,			\
 472	       (unsigned long long)btrfs_header_bytenr(eb),	\
 473	       (unsigned long long)root->objectid, slot)
 474
 475static noinline int check_leaf(struct btrfs_root *root,
 476			       struct extent_buffer *leaf)
 477{
 478	struct btrfs_key key;
 479	struct btrfs_key leaf_key;
 480	u32 nritems = btrfs_header_nritems(leaf);
 481	int slot;
 482
 483	if (nritems == 0)
 484		return 0;
 485
 486	/* Check the 0 item */
 487	if (btrfs_item_offset_nr(leaf, 0) + btrfs_item_size_nr(leaf, 0) !=
 488	    BTRFS_LEAF_DATA_SIZE(root)) {
 489		CORRUPT("invalid item offset size pair", leaf, root, 0);
 490		return -EIO;
 491	}
 492
 493	/*
 494	 * Check to make sure each items keys are in the correct order and their
 495	 * offsets make sense.  We only have to loop through nritems-1 because
 496	 * we check the current slot against the next slot, which verifies the
 497	 * next slot's offset+size makes sense and that the current's slot
 498	 * offset is correct.
 499	 */
 500	for (slot = 0; slot < nritems - 1; slot++) {
 501		btrfs_item_key_to_cpu(leaf, &leaf_key, slot);
 502		btrfs_item_key_to_cpu(leaf, &key, slot + 1);
 503
 504		/* Make sure the keys are in the right order */
 505		if (btrfs_comp_cpu_keys(&leaf_key, &key) >= 0) {
 506			CORRUPT("bad key order", leaf, root, slot);
 507			return -EIO;
 508		}
 509
 510		/*
 511		 * Make sure the offset and ends are right, remember that the
 512		 * item data starts at the end of the leaf and grows towards the
 513		 * front.
 514		 */
 515		if (btrfs_item_offset_nr(leaf, slot) !=
 516			btrfs_item_end_nr(leaf, slot + 1)) {
 517			CORRUPT("slot offset bad", leaf, root, slot);
 518			return -EIO;
 519		}
 520
 521		/*
 522		 * Check to make sure that we don't point outside of the leaf,
 523		 * just incase all the items are consistent to eachother, but
 524		 * all point outside of the leaf.
 525		 */
 526		if (btrfs_item_end_nr(leaf, slot) >
 527		    BTRFS_LEAF_DATA_SIZE(root)) {
 528			CORRUPT("slot end outside of leaf", leaf, root, slot);
 529			return -EIO;
 530		}
 531	}
 532
 533	return 0;
 534}
 535
 536struct extent_buffer *find_eb_for_page(struct extent_io_tree *tree,
 537				       struct page *page, int max_walk)
 538{
 539	struct extent_buffer *eb;
 540	u64 start = page_offset(page);
 541	u64 target = start;
 542	u64 min_start;
 543
 544	if (start < max_walk)
 545		min_start = 0;
 546	else
 547		min_start = start - max_walk;
 548
 549	while (start >= min_start) {
 550		eb = find_extent_buffer(tree, start, 0);
 551		if (eb) {
 552			/*
 553			 * we found an extent buffer and it contains our page
 554			 * horray!
 555			 */
 556			if (eb->start <= target &&
 557			    eb->start + eb->len > target)
 558				return eb;
 559
 560			/* we found an extent buffer that wasn't for us */
 561			free_extent_buffer(eb);
 562			return NULL;
 563		}
 564		if (start == 0)
 565			break;
 566		start -= PAGE_CACHE_SIZE;
 567	}
 568	return NULL;
 569}
 570
 571static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
 572			       struct extent_state *state, int mirror)
 573{
 574	struct extent_io_tree *tree;
 575	u64 found_start;
 576	int found_level;
 577	struct extent_buffer *eb;
 578	struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 
 
 579	int ret = 0;
 
 580	int reads_done;
 581
 582	if (!page->private)
 583		goto out;
 584
 585	tree = &BTRFS_I(page->mapping->host)->io_tree;
 586	eb = (struct extent_buffer *)page->private;
 587
 588	/* the pending IO might have been the only thing that kept this buffer
 589	 * in memory.  Make sure we have a ref for all this other checks
 590	 */
 591	extent_buffer_get(eb);
 592
 593	reads_done = atomic_dec_and_test(&eb->io_pages);
 594	if (!reads_done)
 595		goto err;
 596
 597	eb->read_mirror = mirror;
 598	if (test_bit(EXTENT_BUFFER_IOERR, &eb->bflags)) {
 599		ret = -EIO;
 600		goto err;
 601	}
 602
 603	found_start = btrfs_header_bytenr(eb);
 604	if (found_start != eb->start) {
 605		printk_ratelimited(KERN_INFO "btrfs bad tree block start "
 606			       "%llu %llu\n",
 607			       (unsigned long long)found_start,
 608			       (unsigned long long)eb->start);
 609		ret = -EIO;
 610		goto err;
 611	}
 612	if (check_tree_block_fsid(root, eb)) {
 613		printk_ratelimited(KERN_INFO "btrfs bad fsid on block %llu\n",
 614			       (unsigned long long)eb->start);
 615		ret = -EIO;
 616		goto err;
 617	}
 618	found_level = btrfs_header_level(eb);
 
 
 
 
 
 
 619
 620	btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb),
 621				       eb, found_level);
 622
 623	ret = csum_tree_block(root, eb, 1);
 624	if (ret) {
 625		ret = -EIO;
 
 
 
 
 
 
 
 
 
 
 
 
 
 626		goto err;
 627	}
 628
 629	/*
 630	 * If this is a leaf block and it is corrupt, set the corrupt bit so
 631	 * that we don't try and read the other copies of this block, just
 632	 * return -EIO.
 633	 */
 634	if (found_level == 0 && check_leaf(root, eb)) {
 635		set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 636		ret = -EIO;
 637	}
 638
 
 
 
 639	if (!ret)
 640		set_extent_buffer_uptodate(eb);
 
 
 
 
 641err:
 642	if (test_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) {
 643		clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags);
 644		btree_readahead_hook(root, eb, eb->start, ret);
 645	}
 646
 647	if (ret)
 
 
 
 
 
 
 648		clear_extent_buffer_uptodate(eb);
 
 649	free_extent_buffer(eb);
 650out:
 651	return ret;
 652}
 653
 654static int btree_io_failed_hook(struct page *page, int failed_mirror)
 655{
 656	struct extent_buffer *eb;
 657	struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 658
 659	eb = (struct extent_buffer *)page->private;
 660	set_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
 661	eb->read_mirror = failed_mirror;
 662	if (test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
 663		btree_readahead_hook(root, eb, eb->start, -EIO);
 664	return -EIO;	/* we fixed nothing */
 665}
 666
 667static void end_workqueue_bio(struct bio *bio, int err)
 668{
 669	struct end_io_wq *end_io_wq = bio->bi_private;
 670	struct btrfs_fs_info *fs_info;
 
 
 671
 672	fs_info = end_io_wq->info;
 673	end_io_wq->error = err;
 674	end_io_wq->work.func = end_workqueue_fn;
 675	end_io_wq->work.flags = 0;
 676
 677	if (bio->bi_rw & REQ_WRITE) {
 678		if (end_io_wq->metadata == 1)
 679			btrfs_queue_worker(&fs_info->endio_meta_write_workers,
 680					   &end_io_wq->work);
 681		else if (end_io_wq->metadata == 2)
 682			btrfs_queue_worker(&fs_info->endio_freespace_worker,
 683					   &end_io_wq->work);
 684		else
 685			btrfs_queue_worker(&fs_info->endio_write_workers,
 686					   &end_io_wq->work);
 
 
 687	} else {
 688		if (end_io_wq->metadata)
 689			btrfs_queue_worker(&fs_info->endio_meta_workers,
 690					   &end_io_wq->work);
 691		else
 692			btrfs_queue_worker(&fs_info->endio_workers,
 693					   &end_io_wq->work);
 
 
 
 
 
 
 
 
 694	}
 
 
 
 695}
 696
 697/*
 698 * For the metadata arg you want
 699 *
 700 * 0 - if data
 701 * 1 - if normal metadta
 702 * 2 - if writing to the free space cache area
 703 */
 704int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
 705			int metadata)
 706{
 707	struct end_io_wq *end_io_wq;
 708	end_io_wq = kmalloc(sizeof(*end_io_wq), GFP_NOFS);
 
 709	if (!end_io_wq)
 710		return -ENOMEM;
 711
 712	end_io_wq->private = bio->bi_private;
 713	end_io_wq->end_io = bio->bi_end_io;
 714	end_io_wq->info = info;
 715	end_io_wq->error = 0;
 716	end_io_wq->bio = bio;
 717	end_io_wq->metadata = metadata;
 718
 719	bio->bi_private = end_io_wq;
 720	bio->bi_end_io = end_workqueue_bio;
 721	return 0;
 722}
 723
 724unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info)
 725{
 726	unsigned long limit = min_t(unsigned long,
 727				    info->workers.max_workers,
 728				    info->fs_devices->open_devices);
 729	return 256 * limit;
 730}
 731
 732static void run_one_async_start(struct btrfs_work *work)
 733{
 734	struct async_submit_bio *async;
 735	int ret;
 736
 737	async = container_of(work, struct  async_submit_bio, work);
 738	ret = async->submit_bio_start(async->inode, async->rw, async->bio,
 739				      async->mirror_num, async->bio_flags,
 740				      async->bio_offset);
 741	if (ret)
 742		async->error = ret;
 743}
 744
 
 
 
 
 
 
 
 
 745static void run_one_async_done(struct btrfs_work *work)
 746{
 747	struct btrfs_fs_info *fs_info;
 748	struct async_submit_bio *async;
 749	int limit;
 
 750
 751	async = container_of(work, struct  async_submit_bio, work);
 752	fs_info = BTRFS_I(async->inode)->root->fs_info;
 753
 754	limit = btrfs_async_submit_limit(fs_info);
 755	limit = limit * 2 / 3;
 756
 757	atomic_dec(&fs_info->nr_async_submits);
 758
 759	if (atomic_read(&fs_info->nr_async_submits) < limit &&
 760	    waitqueue_active(&fs_info->async_submit_wait))
 761		wake_up(&fs_info->async_submit_wait);
 762
 763	/* If an error occured we just want to clean up the bio and move on */
 764	if (async->error) {
 765		bio_endio(async->bio, async->error);
 
 766		return;
 767	}
 768
 769	async->submit_bio_done(async->inode, async->rw, async->bio,
 770			       async->mirror_num, async->bio_flags,
 771			       async->bio_offset);
 
 
 
 772}
 773
 774static void run_one_async_free(struct btrfs_work *work)
 775{
 776	struct async_submit_bio *async;
 777
 778	async = container_of(work, struct  async_submit_bio, work);
 779	kfree(async);
 780}
 781
 782int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
 783			int rw, struct bio *bio, int mirror_num,
 784			unsigned long bio_flags,
 785			u64 bio_offset,
 786			extent_submit_bio_hook_t *submit_bio_start,
 787			extent_submit_bio_hook_t *submit_bio_done)
 788{
 789	struct async_submit_bio *async;
 790
 791	async = kmalloc(sizeof(*async), GFP_NOFS);
 792	if (!async)
 793		return -ENOMEM;
 794
 795	async->inode = inode;
 796	async->rw = rw;
 797	async->bio = bio;
 798	async->mirror_num = mirror_num;
 799	async->submit_bio_start = submit_bio_start;
 800	async->submit_bio_done = submit_bio_done;
 801
 802	async->work.func = run_one_async_start;
 803	async->work.ordered_func = run_one_async_done;
 804	async->work.ordered_free = run_one_async_free;
 805
 806	async->work.flags = 0;
 807	async->bio_flags = bio_flags;
 808	async->bio_offset = bio_offset;
 809
 810	async->error = 0;
 811
 812	atomic_inc(&fs_info->nr_async_submits);
 813
 814	if (rw & REQ_SYNC)
 815		btrfs_set_work_high_prio(&async->work);
 816
 817	btrfs_queue_worker(&fs_info->workers, &async->work);
 818
 819	while (atomic_read(&fs_info->async_submit_draining) &&
 820	      atomic_read(&fs_info->nr_async_submits)) {
 821		wait_event(fs_info->async_submit_wait,
 822			   (atomic_read(&fs_info->nr_async_submits) == 0));
 823	}
 824
 
 825	return 0;
 826}
 827
 828static int btree_csum_one_bio(struct bio *bio)
 829{
 830	struct bio_vec *bvec = bio->bi_io_vec;
 831	int bio_index = 0;
 832	struct btrfs_root *root;
 833	int ret = 0;
 
 834
 835	WARN_ON(bio->bi_vcnt <= 0);
 836	while (bio_index < bio->bi_vcnt) {
 837		root = BTRFS_I(bvec->bv_page->mapping->host)->root;
 838		ret = csum_dirty_buffer(root, bvec->bv_page);
 839		if (ret)
 840			break;
 841		bio_index++;
 842		bvec++;
 843	}
 844	return ret;
 
 845}
 846
 847static int __btree_submit_bio_start(struct inode *inode, int rw,
 848				    struct bio *bio, int mirror_num,
 849				    unsigned long bio_flags,
 850				    u64 bio_offset)
 851{
 852	/*
 853	 * when we're called for a write, we're already in the async
 854	 * submission context.  Just jump into btrfs_map_bio
 855	 */
 856	return btree_csum_one_bio(bio);
 857}
 858
 859static int __btree_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
 860				 int mirror_num, unsigned long bio_flags,
 861				 u64 bio_offset)
 862{
 863	/*
 864	 * when we're called for a write, we're already in the async
 865	 * submission context.  Just jump into btrfs_map_bio
 866	 */
 867	return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio, mirror_num, 1);
 868}
 869
 870static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
 871				 int mirror_num, unsigned long bio_flags,
 872				 u64 bio_offset)
 873{
 874	int ret;
 875
 876	if (!(rw & REQ_WRITE)) {
 877
 
 878		/*
 879		 * called for a read, do the setup so that checksum validation
 880		 * can happen in the async kernel threads
 881		 */
 882		ret = btrfs_bio_wq_end_io(BTRFS_I(inode)->root->fs_info,
 883					  bio, 1);
 
 
 
 
 
 884		if (ret)
 885			return ret;
 886		return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
 887				     mirror_num, 0);
 
 
 
 
 
 
 888	}
 889
 890	/*
 891	 * kthread helpers are used to submit writes so that checksumming
 892	 * can happen in parallel across all CPUs
 893	 */
 894	return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
 895				   inode, rw, bio, mirror_num, 0,
 896				   bio_offset,
 897				   __btree_submit_bio_start,
 898				   __btree_submit_bio_done);
 899}
 900
 901#ifdef CONFIG_MIGRATION
 902static int btree_migratepage(struct address_space *mapping,
 903			struct page *newpage, struct page *page,
 904			enum migrate_mode mode)
 905{
 906	/*
 907	 * we can't safely write a btree page from here,
 908	 * we haven't done the locking hook
 909	 */
 910	if (PageDirty(page))
 911		return -EAGAIN;
 912	/*
 913	 * Buffers may be managed in a filesystem specific way.
 914	 * We must have no buffers or drop them.
 915	 */
 916	if (page_has_private(page) &&
 917	    !try_to_release_page(page, GFP_KERNEL))
 918		return -EAGAIN;
 919	return migrate_page(mapping, newpage, page, mode);
 920}
 921#endif
 922
 923
 924static int btree_writepages(struct address_space *mapping,
 925			    struct writeback_control *wbc)
 926{
 927	struct extent_io_tree *tree;
 928	tree = &BTRFS_I(mapping->host)->io_tree;
 
 929	if (wbc->sync_mode == WB_SYNC_NONE) {
 930		struct btrfs_root *root = BTRFS_I(mapping->host)->root;
 931		u64 num_dirty;
 932		unsigned long thresh = 32 * 1024 * 1024;
 933
 934		if (wbc->for_kupdate)
 935			return 0;
 936
 
 937		/* this is a bit racy, but that's ok */
 938		num_dirty = root->fs_info->dirty_metadata_bytes;
 939		if (num_dirty < thresh)
 
 
 940			return 0;
 941	}
 942	return btree_write_cache_pages(mapping, wbc);
 943}
 944
 945static int btree_readpage(struct file *file, struct page *page)
 946{
 947	struct extent_io_tree *tree;
 948	tree = &BTRFS_I(page->mapping->host)->io_tree;
 949	return extent_read_full_page(tree, page, btree_get_extent, 0);
 950}
 951
 952static int btree_releasepage(struct page *page, gfp_t gfp_flags)
 953{
 954	if (PageWriteback(page) || PageDirty(page))
 955		return 0;
 956	/*
 957	 * We need to mask out eg. __GFP_HIGHMEM and __GFP_DMA32 as we're doing
 958	 * slab allocation from alloc_extent_state down the callchain where
 959	 * it'd hit a BUG_ON as those flags are not allowed.
 960	 */
 961	gfp_flags &= ~GFP_SLAB_BUG_MASK;
 962
 963	return try_release_extent_buffer(page, gfp_flags);
 964}
 965
 966static void btree_invalidatepage(struct page *page, unsigned long offset)
 
 967{
 968	struct extent_io_tree *tree;
 969	tree = &BTRFS_I(page->mapping->host)->io_tree;
 970	extent_invalidatepage(tree, page, offset);
 971	btree_releasepage(page, GFP_NOFS);
 972	if (PagePrivate(page)) {
 973		printk(KERN_WARNING "btrfs warning page private not zero "
 974		       "on page %llu\n", (unsigned long long)page_offset(page));
 
 975		ClearPagePrivate(page);
 976		set_page_private(page, 0);
 977		page_cache_release(page);
 978	}
 979}
 980
 981static int btree_set_page_dirty(struct page *page)
 982{
 
 983	struct extent_buffer *eb;
 984
 985	BUG_ON(!PagePrivate(page));
 986	eb = (struct extent_buffer *)page->private;
 987	BUG_ON(!eb);
 988	BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
 989	BUG_ON(!atomic_read(&eb->refs));
 990	btrfs_assert_tree_locked(eb);
 
 991	return __set_page_dirty_nobuffers(page);
 992}
 993
 994static const struct address_space_operations btree_aops = {
 995	.readpage	= btree_readpage,
 996	.writepages	= btree_writepages,
 997	.releasepage	= btree_releasepage,
 998	.invalidatepage = btree_invalidatepage,
 999#ifdef CONFIG_MIGRATION
1000	.migratepage	= btree_migratepage,
1001#endif
1002	.set_page_dirty = btree_set_page_dirty,
1003};
1004
1005int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
1006			 u64 parent_transid)
1007{
1008	struct extent_buffer *buf = NULL;
1009	struct inode *btree_inode = root->fs_info->btree_inode;
1010	int ret = 0;
 
 
 
 
 
 
 
 
 
 
1011
1012	buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1013	if (!buf)
1014		return 0;
1015	read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
1016				 buf, 0, WAIT_NONE, btree_get_extent, 0);
1017	free_extent_buffer(buf);
1018	return ret;
1019}
1020
1021int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, u32 blocksize,
1022			 int mirror_num, struct extent_buffer **eb)
 
 
 
 
 
 
 
 
 
1023{
1024	struct extent_buffer *buf = NULL;
1025	struct inode *btree_inode = root->fs_info->btree_inode;
1026	struct extent_io_tree *io_tree = &BTRFS_I(btree_inode)->io_tree;
1027	int ret;
1028
1029	buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1030	if (!buf)
1031		return 0;
1032
1033	set_bit(EXTENT_BUFFER_READAHEAD, &buf->bflags);
1034
1035	ret = read_extent_buffer_pages(io_tree, buf, 0, WAIT_PAGE_LOCK,
1036				       btree_get_extent, mirror_num);
1037	if (ret) {
1038		free_extent_buffer(buf);
1039		return ret;
1040	}
 
1041
1042	if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) {
1043		free_extent_buffer(buf);
1044		return -EIO;
1045	} else if (extent_buffer_uptodate(buf)) {
1046		*eb = buf;
1047	} else {
1048		free_extent_buffer(buf);
1049	}
1050	return 0;
1051}
1052
1053struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
1054					    u64 bytenr, u32 blocksize)
1055{
1056	struct inode *btree_inode = root->fs_info->btree_inode;
1057	struct extent_buffer *eb;
1058	eb = find_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
1059				bytenr, blocksize);
1060	return eb;
1061}
1062
1063struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
1064						 u64 bytenr, u32 blocksize)
1065{
1066	struct inode *btree_inode = root->fs_info->btree_inode;
1067	struct extent_buffer *eb;
1068
1069	eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
1070				 bytenr, blocksize);
1071	return eb;
1072}
1073
1074
1075int btrfs_write_tree_block(struct extent_buffer *buf)
1076{
1077	return filemap_fdatawrite_range(buf->pages[0]->mapping, buf->start,
1078					buf->start + buf->len - 1);
1079}
1080
1081int btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
1082{
1083	return filemap_fdatawait_range(buf->pages[0]->mapping,
1084				       buf->start, buf->start + buf->len - 1);
1085}
1086
1087struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
1088				      u32 blocksize, u64 parent_transid)
1089{
1090	struct extent_buffer *buf = NULL;
1091	int ret;
1092
1093	buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1094	if (!buf)
1095		return NULL;
1096
1097	ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
1098	return buf;
 
 
 
1099
 
 
1100}
1101
1102void clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1103		      struct extent_buffer *buf)
1104{
1105	if (btrfs_header_generation(buf) ==
1106	    root->fs_info->running_transaction->transid) {
1107		btrfs_assert_tree_locked(buf);
1108
1109		if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
1110			spin_lock(&root->fs_info->delalloc_lock);
1111			if (root->fs_info->dirty_metadata_bytes >= buf->len)
1112				root->fs_info->dirty_metadata_bytes -= buf->len;
1113			else {
1114				spin_unlock(&root->fs_info->delalloc_lock);
1115				btrfs_panic(root->fs_info, -EOVERFLOW,
1116					  "Can't clear %lu bytes from "
1117					  " dirty_mdatadata_bytes (%lu)",
1118					  buf->len,
1119					  root->fs_info->dirty_metadata_bytes);
1120			}
1121			spin_unlock(&root->fs_info->delalloc_lock);
1122		}
1123
1124		/* ugh, clear_extent_buffer_dirty needs to lock the page */
1125		btrfs_set_lock_blocking(buf);
1126		clear_extent_buffer_dirty(buf);
1127	}
1128}
1129
1130static void __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
1131			 u32 stripesize, struct btrfs_root *root,
1132			 struct btrfs_fs_info *fs_info,
1133			 u64 objectid)
1134{
 
1135	root->node = NULL;
1136	root->commit_root = NULL;
1137	root->sectorsize = sectorsize;
1138	root->nodesize = nodesize;
1139	root->leafsize = leafsize;
1140	root->stripesize = stripesize;
1141	root->ref_cows = 0;
1142	root->track_dirty = 0;
1143	root->in_radix = 0;
1144	root->orphan_item_inserted = 0;
1145	root->orphan_cleanup_state = 0;
1146
1147	root->objectid = objectid;
1148	root->last_trans = 0;
1149	root->highest_objectid = 0;
1150	root->name = NULL;
 
1151	root->inode_tree = RB_ROOT;
1152	INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
1153	root->block_rsv = NULL;
1154	root->orphan_block_rsv = NULL;
1155
1156	INIT_LIST_HEAD(&root->dirty_list);
1157	INIT_LIST_HEAD(&root->root_list);
1158	spin_lock_init(&root->orphan_lock);
 
 
 
 
 
 
1159	spin_lock_init(&root->inode_lock);
 
 
1160	spin_lock_init(&root->accounting_lock);
 
 
 
1161	mutex_init(&root->objectid_mutex);
1162	mutex_init(&root->log_mutex);
 
 
1163	init_waitqueue_head(&root->log_writer_wait);
1164	init_waitqueue_head(&root->log_commit_wait[0]);
1165	init_waitqueue_head(&root->log_commit_wait[1]);
 
 
1166	atomic_set(&root->log_commit[0], 0);
1167	atomic_set(&root->log_commit[1], 0);
1168	atomic_set(&root->log_writers, 0);
1169	atomic_set(&root->orphan_inodes, 0);
1170	root->log_batch = 0;
 
 
 
1171	root->log_transid = 0;
 
1172	root->last_log_commit = 0;
1173	extent_io_tree_init(&root->dirty_log_pages,
1174			     fs_info->btree_inode->i_mapping);
 
1175
1176	memset(&root->root_key, 0, sizeof(root->root_key));
1177	memset(&root->root_item, 0, sizeof(root->root_item));
1178	memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
1179	memset(&root->root_kobj, 0, sizeof(root->root_kobj));
1180	root->defrag_trans_start = fs_info->generation;
1181	init_completion(&root->kobj_unregister);
1182	root->defrag_running = 0;
1183	root->root_key.objectid = objectid;
1184	root->anon_dev = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1185}
 
1186
1187static int __must_check find_and_setup_root(struct btrfs_root *tree_root,
1188					    struct btrfs_fs_info *fs_info,
1189					    u64 objectid,
1190					    struct btrfs_root *root)
1191{
1192	int ret;
1193	u32 blocksize;
1194	u64 generation;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1195
1196	__setup_root(tree_root->nodesize, tree_root->leafsize,
1197		     tree_root->sectorsize, tree_root->stripesize,
1198		     root, fs_info, objectid);
1199	ret = btrfs_find_last_root(tree_root, objectid,
1200				   &root->root_item, &root->root_key);
1201	if (ret > 0)
1202		return -ENOENT;
1203	else if (ret < 0)
1204		return ret;
1205
1206	generation = btrfs_root_generation(&root->root_item);
1207	blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
1208	root->commit_root = NULL;
1209	root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
1210				     blocksize, generation);
1211	if (!root->node || !btrfs_buffer_uptodate(root->node, generation, 0)) {
1212		free_extent_buffer(root->node);
1213		root->node = NULL;
1214		return -EIO;
1215	}
 
 
 
 
1216	root->commit_root = btrfs_root_node(root);
1217	return 0;
1218}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1219
1220static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info)
1221{
1222	struct btrfs_root *root = kzalloc(sizeof(*root), GFP_NOFS);
1223	if (root)
1224		root->fs_info = fs_info;
1225	return root;
 
 
 
 
 
 
 
 
 
 
1226}
1227
1228static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
1229					 struct btrfs_fs_info *fs_info)
1230{
1231	struct btrfs_root *root;
1232	struct btrfs_root *tree_root = fs_info->tree_root;
1233	struct extent_buffer *leaf;
1234
1235	root = btrfs_alloc_root(fs_info);
1236	if (!root)
1237		return ERR_PTR(-ENOMEM);
1238
1239	__setup_root(tree_root->nodesize, tree_root->leafsize,
1240		     tree_root->sectorsize, tree_root->stripesize,
1241		     root, fs_info, BTRFS_TREE_LOG_OBJECTID);
1242
1243	root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1244	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1245	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
 
1246	/*
 
 
1247	 * log trees do not get reference counted because they go away
1248	 * before a real commit is actually done.  They do store pointers
1249	 * to file data extents, and those reference counts still get
1250	 * updated (along with back refs to the log tree).
1251	 */
1252	root->ref_cows = 0;
1253
1254	leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
1255				      BTRFS_TREE_LOG_OBJECTID, NULL,
1256				      0, 0, 0);
1257	if (IS_ERR(leaf)) {
1258		kfree(root);
1259		return ERR_CAST(leaf);
1260	}
1261
1262	memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
1263	btrfs_set_header_bytenr(leaf, leaf->start);
1264	btrfs_set_header_generation(leaf, trans->transid);
1265	btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
1266	btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
1267	root->node = leaf;
1268
1269	write_extent_buffer(root->node, root->fs_info->fsid,
1270			    (unsigned long)btrfs_header_fsid(root->node),
1271			    BTRFS_FSID_SIZE);
1272	btrfs_mark_buffer_dirty(root->node);
1273	btrfs_tree_unlock(root->node);
1274	return root;
1275}
1276
1277int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1278			     struct btrfs_fs_info *fs_info)
1279{
1280	struct btrfs_root *log_root;
1281
1282	log_root = alloc_log_tree(trans, fs_info);
1283	if (IS_ERR(log_root))
1284		return PTR_ERR(log_root);
1285	WARN_ON(fs_info->log_root_tree);
1286	fs_info->log_root_tree = log_root;
1287	return 0;
1288}
1289
1290int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1291		       struct btrfs_root *root)
1292{
 
1293	struct btrfs_root *log_root;
1294	struct btrfs_inode_item *inode_item;
1295
1296	log_root = alloc_log_tree(trans, root->fs_info);
1297	if (IS_ERR(log_root))
1298		return PTR_ERR(log_root);
1299
1300	log_root->last_trans = trans->transid;
1301	log_root->root_key.offset = root->root_key.objectid;
1302
1303	inode_item = &log_root->root_item.inode;
1304	inode_item->generation = cpu_to_le64(1);
1305	inode_item->size = cpu_to_le64(3);
1306	inode_item->nlink = cpu_to_le32(1);
1307	inode_item->nbytes = cpu_to_le64(root->leafsize);
1308	inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
 
1309
1310	btrfs_set_root_node(&log_root->root_item, log_root->node);
1311
1312	WARN_ON(root->log_root);
1313	root->log_root = log_root;
1314	root->log_transid = 0;
 
1315	root->last_log_commit = 0;
1316	return 0;
1317}
1318
1319struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
1320					       struct btrfs_key *location)
1321{
1322	struct btrfs_root *root;
1323	struct btrfs_fs_info *fs_info = tree_root->fs_info;
1324	struct btrfs_path *path;
1325	struct extent_buffer *l;
1326	u64 generation;
1327	u32 blocksize;
1328	int ret = 0;
1329
1330	root = btrfs_alloc_root(fs_info);
1331	if (!root)
1332		return ERR_PTR(-ENOMEM);
1333	if (location->offset == (u64)-1) {
1334		ret = find_and_setup_root(tree_root, fs_info,
1335					  location->objectid, root);
1336		if (ret) {
1337			kfree(root);
1338			return ERR_PTR(ret);
1339		}
1340		goto out;
1341	}
1342
1343	__setup_root(tree_root->nodesize, tree_root->leafsize,
1344		     tree_root->sectorsize, tree_root->stripesize,
1345		     root, fs_info, location->objectid);
1346
1347	path = btrfs_alloc_path();
1348	if (!path) {
1349		kfree(root);
1350		return ERR_PTR(-ENOMEM);
1351	}
1352	ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
1353	if (ret == 0) {
1354		l = path->nodes[0];
1355		read_extent_buffer(l, &root->root_item,
1356				btrfs_item_ptr_offset(l, path->slots[0]),
1357				sizeof(root->root_item));
1358		memcpy(&root->root_key, location, sizeof(*location));
1359	}
1360	btrfs_free_path(path);
1361	if (ret) {
1362		kfree(root);
1363		if (ret > 0)
1364			ret = -ENOENT;
1365		return ERR_PTR(ret);
1366	}
1367
1368	generation = btrfs_root_generation(&root->root_item);
1369	blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
1370	root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
1371				     blocksize, generation);
 
 
 
 
 
 
 
 
 
1372	root->commit_root = btrfs_root_node(root);
1373	BUG_ON(!root->node); /* -ENOMEM */
1374out:
1375	if (location->objectid != BTRFS_TREE_LOG_OBJECTID) {
1376		root->ref_cows = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1377		btrfs_check_and_init_root_item(&root->root_item);
1378	}
1379
1380	return root;
1381}
1382
1383struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
1384					      struct btrfs_key *location)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1385{
1386	struct btrfs_root *root;
 
 
1387	int ret;
1388
1389	if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1390		return fs_info->tree_root;
1391	if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
1392		return fs_info->extent_root;
1393	if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
1394		return fs_info->chunk_root;
1395	if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
1396		return fs_info->dev_root;
1397	if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
1398		return fs_info->csum_root;
 
 
 
 
 
 
 
 
 
1399again:
1400	spin_lock(&fs_info->fs_roots_radix_lock);
1401	root = radix_tree_lookup(&fs_info->fs_roots_radix,
1402				 (unsigned long)location->objectid);
1403	spin_unlock(&fs_info->fs_roots_radix_lock);
1404	if (root)
1405		return root;
 
1406
1407	root = btrfs_read_fs_root_no_radix(fs_info->tree_root, location);
1408	if (IS_ERR(root))
1409		return root;
1410
1411	root->free_ino_ctl = kzalloc(sizeof(*root->free_ino_ctl), GFP_NOFS);
1412	root->free_ino_pinned = kzalloc(sizeof(*root->free_ino_pinned),
1413					GFP_NOFS);
1414	if (!root->free_ino_pinned || !root->free_ino_ctl) {
1415		ret = -ENOMEM;
1416		goto fail;
1417	}
1418
1419	btrfs_init_free_ino_ctl(root);
1420	mutex_init(&root->fs_commit_mutex);
1421	spin_lock_init(&root->cache_lock);
1422	init_waitqueue_head(&root->cache_wait);
1423
1424	ret = get_anon_bdev(&root->anon_dev);
1425	if (ret)
1426		goto fail;
1427
1428	if (btrfs_root_refs(&root->root_item) == 0) {
1429		ret = -ENOENT;
 
1430		goto fail;
1431	}
 
 
 
1432
1433	ret = btrfs_find_orphan_item(fs_info->tree_root, location->objectid);
 
1434	if (ret < 0)
1435		goto fail;
1436	if (ret == 0)
1437		root->orphan_item_inserted = 1;
1438
1439	ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
1440	if (ret)
1441		goto fail;
1442
1443	spin_lock(&fs_info->fs_roots_radix_lock);
1444	ret = radix_tree_insert(&fs_info->fs_roots_radix,
1445				(unsigned long)root->root_key.objectid,
1446				root);
1447	if (ret == 0)
1448		root->in_radix = 1;
1449
1450	spin_unlock(&fs_info->fs_roots_radix_lock);
1451	radix_tree_preload_end();
1452	if (ret) {
1453		if (ret == -EEXIST) {
1454			free_fs_root(root);
1455			goto again;
1456		}
1457		goto fail;
1458	}
1459
1460	ret = btrfs_find_dead_roots(fs_info->tree_root,
1461				    root->root_key.objectid);
1462	WARN_ON(ret);
1463	return root;
1464fail:
1465	free_fs_root(root);
1466	return ERR_PTR(ret);
1467}
1468
1469static int btrfs_congested_fn(void *congested_data, int bdi_bits)
1470{
1471	struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
1472	int ret = 0;
1473	struct btrfs_device *device;
1474	struct backing_dev_info *bdi;
1475
1476	rcu_read_lock();
1477	list_for_each_entry_rcu(device, &info->fs_devices->devices, dev_list) {
1478		if (!device->bdev)
1479			continue;
1480		bdi = blk_get_backing_dev_info(device->bdev);
1481		if (bdi && bdi_congested(bdi, bdi_bits)) {
1482			ret = 1;
1483			break;
1484		}
1485	}
1486	rcu_read_unlock();
1487	return ret;
1488}
1489
1490/*
1491 * If this fails, caller must call bdi_destroy() to get rid of the
1492 * bdi again.
1493 */
1494static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
1495{
1496	int err;
1497
1498	bdi->capabilities = BDI_CAP_MAP_COPY;
1499	err = bdi_setup_and_register(bdi, "btrfs", BDI_CAP_MAP_COPY);
1500	if (err)
1501		return err;
1502
1503	bdi->ra_pages	= default_backing_dev_info.ra_pages;
1504	bdi->congested_fn	= btrfs_congested_fn;
1505	bdi->congested_data	= info;
1506	return 0;
1507}
1508
1509/*
1510 * called by the kthread helper functions to finally call the bio end_io
1511 * functions.  This is where read checksum verification actually happens
1512 */
1513static void end_workqueue_fn(struct btrfs_work *work)
1514{
1515	struct bio *bio;
1516	struct end_io_wq *end_io_wq;
1517	struct btrfs_fs_info *fs_info;
1518	int error;
1519
1520	end_io_wq = container_of(work, struct end_io_wq, work);
1521	bio = end_io_wq->bio;
1522	fs_info = end_io_wq->info;
1523
1524	error = end_io_wq->error;
1525	bio->bi_private = end_io_wq->private;
1526	bio->bi_end_io = end_io_wq->end_io;
1527	kfree(end_io_wq);
1528	bio_endio(bio, error);
1529}
1530
1531static int cleaner_kthread(void *arg)
1532{
1533	struct btrfs_root *root = arg;
 
 
 
 
 
 
 
1534
1535	do {
1536		vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
 
 
 
 
 
 
 
 
 
 
 
1537
1538		if (!(root->fs_info->sb->s_flags & MS_RDONLY) &&
1539		    mutex_trylock(&root->fs_info->cleaner_mutex)) {
1540			btrfs_run_delayed_iputs(root);
1541			btrfs_clean_old_snapshots(root);
1542			mutex_unlock(&root->fs_info->cleaner_mutex);
1543			btrfs_run_defrag_inodes(root->fs_info);
 
1544		}
1545
1546		if (!try_to_freeze()) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1547			set_current_state(TASK_INTERRUPTIBLE);
1548			if (!kthread_should_stop())
1549				schedule();
1550			__set_current_state(TASK_RUNNING);
1551		}
1552	} while (!kthread_should_stop());
1553	return 0;
1554}
1555
1556static int transaction_kthread(void *arg)
1557{
1558	struct btrfs_root *root = arg;
 
1559	struct btrfs_trans_handle *trans;
1560	struct btrfs_transaction *cur;
1561	u64 transid;
1562	unsigned long now;
1563	unsigned long delay;
1564	bool cannot_commit;
1565
1566	do {
1567		cannot_commit = false;
1568		delay = HZ * 30;
1569		vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
1570		mutex_lock(&root->fs_info->transaction_kthread_mutex);
1571
1572		spin_lock(&root->fs_info->trans_lock);
1573		cur = root->fs_info->running_transaction;
1574		if (!cur) {
1575			spin_unlock(&root->fs_info->trans_lock);
1576			goto sleep;
1577		}
1578
1579		now = get_seconds();
1580		if (!cur->blocked &&
1581		    (now < cur->start_time || now - cur->start_time < 30)) {
1582			spin_unlock(&root->fs_info->trans_lock);
 
 
1583			delay = HZ * 5;
1584			goto sleep;
1585		}
1586		transid = cur->transid;
1587		spin_unlock(&root->fs_info->trans_lock);
1588
1589		/* If the file system is aborted, this will always fail. */
1590		trans = btrfs_join_transaction(root);
1591		if (IS_ERR(trans)) {
1592			cannot_commit = true;
 
1593			goto sleep;
1594		}
1595		if (transid == trans->transid) {
1596			btrfs_commit_transaction(trans, root);
1597		} else {
1598			btrfs_end_transaction(trans, root);
1599		}
1600sleep:
1601		wake_up_process(root->fs_info->cleaner_kthread);
1602		mutex_unlock(&root->fs_info->transaction_kthread_mutex);
1603
1604		if (!try_to_freeze()) {
1605			set_current_state(TASK_INTERRUPTIBLE);
1606			if (!kthread_should_stop() &&
1607			    (!btrfs_transaction_blocked(root->fs_info) ||
1608			     cannot_commit))
1609				schedule_timeout(delay);
1610			__set_current_state(TASK_RUNNING);
1611		}
1612	} while (!kthread_should_stop());
1613	return 0;
1614}
1615
1616/*
1617 * this will find the highest generation in the array of
1618 * root backups.  The index of the highest array is returned,
1619 * or -1 if we can't find anything.
1620 *
1621 * We check to make sure the array is valid by comparing the
1622 * generation of the latest  root in the array with the generation
1623 * in the super block.  If they don't match we pitch it.
1624 */
1625static int find_newest_super_backup(struct btrfs_fs_info *info, u64 newest_gen)
1626{
1627	u64 cur;
1628	int newest_index = -1;
1629	struct btrfs_root_backup *root_backup;
1630	int i;
1631
1632	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
1633		root_backup = info->super_copy->super_roots + i;
1634		cur = btrfs_backup_tree_root_gen(root_backup);
1635		if (cur == newest_gen)
1636			newest_index = i;
1637	}
1638
1639	/* check to see if we actually wrapped around */
1640	if (newest_index == BTRFS_NUM_BACKUP_ROOTS - 1) {
1641		root_backup = info->super_copy->super_roots;
1642		cur = btrfs_backup_tree_root_gen(root_backup);
1643		if (cur == newest_gen)
1644			newest_index = 0;
1645	}
1646	return newest_index;
1647}
1648
1649
1650/*
1651 * find the oldest backup so we know where to store new entries
1652 * in the backup array.  This will set the backup_root_index
1653 * field in the fs_info struct
1654 */
1655static void find_oldest_super_backup(struct btrfs_fs_info *info,
1656				     u64 newest_gen)
1657{
1658	int newest_index = -1;
1659
1660	newest_index = find_newest_super_backup(info, newest_gen);
1661	/* if there was garbage in there, just move along */
1662	if (newest_index == -1) {
1663		info->backup_root_index = 0;
1664	} else {
1665		info->backup_root_index = (newest_index + 1) % BTRFS_NUM_BACKUP_ROOTS;
1666	}
1667}
1668
1669/*
1670 * copy all the root pointers into the super backup array.
1671 * this will bump the backup pointer by one when it is
1672 * done
1673 */
1674static void backup_super_roots(struct btrfs_fs_info *info)
1675{
1676	int next_backup;
1677	struct btrfs_root_backup *root_backup;
1678	int last_backup;
1679
1680	next_backup = info->backup_root_index;
1681	last_backup = (next_backup + BTRFS_NUM_BACKUP_ROOTS - 1) %
1682		BTRFS_NUM_BACKUP_ROOTS;
1683
1684	/*
1685	 * just overwrite the last backup if we're at the same generation
1686	 * this happens only at umount
1687	 */
1688	root_backup = info->super_for_commit->super_roots + last_backup;
1689	if (btrfs_backup_tree_root_gen(root_backup) ==
1690	    btrfs_header_generation(info->tree_root->node))
1691		next_backup = last_backup;
1692
1693	root_backup = info->super_for_commit->super_roots + next_backup;
1694
1695	/*
1696	 * make sure all of our padding and empty slots get zero filled
1697	 * regardless of which ones we use today
1698	 */
1699	memset(root_backup, 0, sizeof(*root_backup));
1700
1701	info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
1702
1703	btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
1704	btrfs_set_backup_tree_root_gen(root_backup,
1705			       btrfs_header_generation(info->tree_root->node));
1706
1707	btrfs_set_backup_tree_root_level(root_backup,
1708			       btrfs_header_level(info->tree_root->node));
1709
1710	btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
1711	btrfs_set_backup_chunk_root_gen(root_backup,
1712			       btrfs_header_generation(info->chunk_root->node));
1713	btrfs_set_backup_chunk_root_level(root_backup,
1714			       btrfs_header_level(info->chunk_root->node));
1715
1716	btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start);
1717	btrfs_set_backup_extent_root_gen(root_backup,
1718			       btrfs_header_generation(info->extent_root->node));
1719	btrfs_set_backup_extent_root_level(root_backup,
1720			       btrfs_header_level(info->extent_root->node));
1721
1722	/*
1723	 * we might commit during log recovery, which happens before we set
1724	 * the fs_root.  Make sure it is valid before we fill it in.
1725	 */
1726	if (info->fs_root && info->fs_root->node) {
1727		btrfs_set_backup_fs_root(root_backup,
1728					 info->fs_root->node->start);
1729		btrfs_set_backup_fs_root_gen(root_backup,
1730			       btrfs_header_generation(info->fs_root->node));
1731		btrfs_set_backup_fs_root_level(root_backup,
1732			       btrfs_header_level(info->fs_root->node));
1733	}
1734
1735	btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
1736	btrfs_set_backup_dev_root_gen(root_backup,
1737			       btrfs_header_generation(info->dev_root->node));
1738	btrfs_set_backup_dev_root_level(root_backup,
1739				       btrfs_header_level(info->dev_root->node));
1740
1741	btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start);
1742	btrfs_set_backup_csum_root_gen(root_backup,
1743			       btrfs_header_generation(info->csum_root->node));
1744	btrfs_set_backup_csum_root_level(root_backup,
1745			       btrfs_header_level(info->csum_root->node));
1746
1747	btrfs_set_backup_total_bytes(root_backup,
1748			     btrfs_super_total_bytes(info->super_copy));
1749	btrfs_set_backup_bytes_used(root_backup,
1750			     btrfs_super_bytes_used(info->super_copy));
1751	btrfs_set_backup_num_devices(root_backup,
1752			     btrfs_super_num_devices(info->super_copy));
1753
1754	/*
1755	 * if we don't copy this out to the super_copy, it won't get remembered
1756	 * for the next commit
1757	 */
1758	memcpy(&info->super_copy->super_roots,
1759	       &info->super_for_commit->super_roots,
1760	       sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
1761}
1762
1763/*
1764 * this copies info out of the root backup array and back into
1765 * the in-memory super block.  It is meant to help iterate through
1766 * the array, so you send it the number of backups you've already
1767 * tried and the last backup index you used.
1768 *
1769 * this returns -1 when it has tried all the backups
1770 */
1771static noinline int next_root_backup(struct btrfs_fs_info *info,
1772				     struct btrfs_super_block *super,
1773				     int *num_backups_tried, int *backup_index)
1774{
1775	struct btrfs_root_backup *root_backup;
1776	int newest = *backup_index;
1777
1778	if (*num_backups_tried == 0) {
1779		u64 gen = btrfs_super_generation(super);
1780
1781		newest = find_newest_super_backup(info, gen);
1782		if (newest == -1)
1783			return -1;
1784
1785		*backup_index = newest;
1786		*num_backups_tried = 1;
1787	} else if (*num_backups_tried == BTRFS_NUM_BACKUP_ROOTS) {
1788		/* we've tried all the backups, all done */
1789		return -1;
1790	} else {
1791		/* jump to the next oldest backup */
1792		newest = (*backup_index + BTRFS_NUM_BACKUP_ROOTS - 1) %
1793			BTRFS_NUM_BACKUP_ROOTS;
1794		*backup_index = newest;
1795		*num_backups_tried += 1;
1796	}
1797	root_backup = super->super_roots + newest;
1798
1799	btrfs_set_super_generation(super,
1800				   btrfs_backup_tree_root_gen(root_backup));
1801	btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
1802	btrfs_set_super_root_level(super,
1803				   btrfs_backup_tree_root_level(root_backup));
1804	btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
1805
1806	/*
1807	 * fixme: the total bytes and num_devices need to match or we should
1808	 * need a fsck
1809	 */
1810	btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
1811	btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
1812	return 0;
1813}
1814
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1815/* helper to cleanup tree roots */
1816static void free_root_pointers(struct btrfs_fs_info *info, int chunk_root)
1817{
1818	free_extent_buffer(info->tree_root->node);
1819	free_extent_buffer(info->tree_root->commit_root);
1820	free_extent_buffer(info->dev_root->node);
1821	free_extent_buffer(info->dev_root->commit_root);
1822	free_extent_buffer(info->extent_root->node);
1823	free_extent_buffer(info->extent_root->commit_root);
1824	free_extent_buffer(info->csum_root->node);
1825	free_extent_buffer(info->csum_root->commit_root);
1826
1827	info->tree_root->node = NULL;
1828	info->tree_root->commit_root = NULL;
1829	info->dev_root->node = NULL;
1830	info->dev_root->commit_root = NULL;
1831	info->extent_root->node = NULL;
1832	info->extent_root->commit_root = NULL;
1833	info->csum_root->node = NULL;
1834	info->csum_root->commit_root = NULL;
1835
1836	if (chunk_root) {
1837		free_extent_buffer(info->chunk_root->node);
1838		free_extent_buffer(info->chunk_root->commit_root);
1839		info->chunk_root->node = NULL;
1840		info->chunk_root->commit_root = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1841	}
1842}
1843
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1844
1845int open_ctree(struct super_block *sb,
1846	       struct btrfs_fs_devices *fs_devices,
1847	       char *options)
1848{
1849	u32 sectorsize;
1850	u32 nodesize;
1851	u32 leafsize;
1852	u32 blocksize;
1853	u32 stripesize;
1854	u64 generation;
1855	u64 features;
 
1856	struct btrfs_key location;
1857	struct buffer_head *bh;
1858	struct btrfs_super_block *disk_super;
1859	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
1860	struct btrfs_root *tree_root;
1861	struct btrfs_root *extent_root;
1862	struct btrfs_root *csum_root;
1863	struct btrfs_root *chunk_root;
1864	struct btrfs_root *dev_root;
1865	struct btrfs_root *log_tree_root;
1866	int ret;
1867	int err = -EINVAL;
1868	int num_backups_tried = 0;
1869	int backup_index = 0;
 
 
1870
1871	tree_root = fs_info->tree_root = btrfs_alloc_root(fs_info);
1872	extent_root = fs_info->extent_root = btrfs_alloc_root(fs_info);
1873	csum_root = fs_info->csum_root = btrfs_alloc_root(fs_info);
1874	chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info);
1875	dev_root = fs_info->dev_root = btrfs_alloc_root(fs_info);
1876
1877	if (!tree_root || !extent_root || !csum_root ||
1878	    !chunk_root || !dev_root) {
1879		err = -ENOMEM;
1880		goto fail;
1881	}
1882
1883	ret = init_srcu_struct(&fs_info->subvol_srcu);
1884	if (ret) {
1885		err = ret;
1886		goto fail;
1887	}
1888
1889	ret = setup_bdi(fs_info, &fs_info->bdi);
1890	if (ret) {
1891		err = ret;
1892		goto fail_srcu;
1893	}
1894
1895	fs_info->btree_inode = new_inode(sb);
1896	if (!fs_info->btree_inode) {
1897		err = -ENOMEM;
1898		goto fail_bdi;
 
 
 
 
 
 
 
 
1899	}
1900
1901	mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
 
 
 
 
 
1902
1903	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
 
1904	INIT_LIST_HEAD(&fs_info->trans_list);
1905	INIT_LIST_HEAD(&fs_info->dead_roots);
1906	INIT_LIST_HEAD(&fs_info->delayed_iputs);
1907	INIT_LIST_HEAD(&fs_info->hashers);
1908	INIT_LIST_HEAD(&fs_info->delalloc_inodes);
1909	INIT_LIST_HEAD(&fs_info->ordered_operations);
1910	INIT_LIST_HEAD(&fs_info->caching_block_groups);
1911	spin_lock_init(&fs_info->delalloc_lock);
1912	spin_lock_init(&fs_info->trans_lock);
1913	spin_lock_init(&fs_info->ref_cache_lock);
1914	spin_lock_init(&fs_info->fs_roots_radix_lock);
1915	spin_lock_init(&fs_info->delayed_iput_lock);
1916	spin_lock_init(&fs_info->defrag_inodes_lock);
1917	spin_lock_init(&fs_info->free_chunk_lock);
1918	spin_lock_init(&fs_info->tree_mod_seq_lock);
 
 
 
1919	rwlock_init(&fs_info->tree_mod_log_lock);
 
 
1920	mutex_init(&fs_info->reloc_mutex);
 
 
1921
1922	init_completion(&fs_info->kobj_unregister);
1923	INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
1924	INIT_LIST_HEAD(&fs_info->space_info);
1925	INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
1926	btrfs_mapping_init(&fs_info->mapping_tree);
1927	btrfs_init_block_rsv(&fs_info->global_block_rsv);
1928	btrfs_init_block_rsv(&fs_info->delalloc_block_rsv);
1929	btrfs_init_block_rsv(&fs_info->trans_block_rsv);
1930	btrfs_init_block_rsv(&fs_info->chunk_block_rsv);
1931	btrfs_init_block_rsv(&fs_info->empty_block_rsv);
1932	btrfs_init_block_rsv(&fs_info->delayed_block_rsv);
1933	atomic_set(&fs_info->nr_async_submits, 0);
 
 
 
 
1934	atomic_set(&fs_info->async_delalloc_pages, 0);
1935	atomic_set(&fs_info->async_submit_draining, 0);
1936	atomic_set(&fs_info->nr_async_bios, 0);
1937	atomic_set(&fs_info->defrag_running, 0);
1938	atomic_set(&fs_info->tree_mod_seq, 0);
 
 
1939	fs_info->sb = sb;
1940	fs_info->max_inline = 8192 * 1024;
1941	fs_info->metadata_ratio = 0;
1942	fs_info->defrag_inodes = RB_ROOT;
1943	fs_info->trans_no_join = 0;
1944	fs_info->free_chunk_space = 0;
1945	fs_info->tree_mod_log = RB_ROOT;
1946
 
1947	/* readahead state */
1948	INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_WAIT);
1949	spin_lock_init(&fs_info->reada_lock);
 
1950
1951	fs_info->thread_pool_size = min_t(unsigned long,
1952					  num_online_cpus() + 2, 8);
1953
1954	INIT_LIST_HEAD(&fs_info->ordered_extents);
1955	spin_lock_init(&fs_info->ordered_extent_lock);
 
 
 
 
 
 
 
 
1956	fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
1957					GFP_NOFS);
1958	if (!fs_info->delayed_root) {
1959		err = -ENOMEM;
1960		goto fail_iput;
1961	}
1962	btrfs_init_delayed_root(fs_info->delayed_root);
1963
1964	mutex_init(&fs_info->scrub_lock);
1965	atomic_set(&fs_info->scrubs_running, 0);
1966	atomic_set(&fs_info->scrub_pause_req, 0);
1967	atomic_set(&fs_info->scrubs_paused, 0);
1968	atomic_set(&fs_info->scrub_cancel_req, 0);
1969	init_waitqueue_head(&fs_info->scrub_pause_wait);
1970	init_rwsem(&fs_info->scrub_super_lock);
1971	fs_info->scrub_workers_refcnt = 0;
1972#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
1973	fs_info->check_integrity_print_mask = 0;
1974#endif
 
 
1975
1976	spin_lock_init(&fs_info->balance_lock);
1977	mutex_init(&fs_info->balance_mutex);
1978	atomic_set(&fs_info->balance_running, 0);
1979	atomic_set(&fs_info->balance_pause_req, 0);
1980	atomic_set(&fs_info->balance_cancel_req, 0);
1981	fs_info->balance_ctl = NULL;
1982	init_waitqueue_head(&fs_info->balance_wait_q);
1983
1984	sb->s_blocksize = 4096;
1985	sb->s_blocksize_bits = blksize_bits(4096);
1986	sb->s_bdi = &fs_info->bdi;
1987
1988	fs_info->btree_inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
1989	set_nlink(fs_info->btree_inode, 1);
1990	/*
1991	 * we set the i_size on the btree inode to the max possible int.
1992	 * the real end of the address space is determined by all of
1993	 * the devices in the system
1994	 */
1995	fs_info->btree_inode->i_size = OFFSET_MAX;
1996	fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
1997	fs_info->btree_inode->i_mapping->backing_dev_info = &fs_info->bdi;
1998
1999	RB_CLEAR_NODE(&BTRFS_I(fs_info->btree_inode)->rb_node);
2000	extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree,
2001			     fs_info->btree_inode->i_mapping);
2002	BTRFS_I(fs_info->btree_inode)->io_tree.track_uptodate = 0;
2003	extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree);
2004
2005	BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops;
2006
2007	BTRFS_I(fs_info->btree_inode)->root = tree_root;
2008	memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
2009	       sizeof(struct btrfs_key));
2010	set_bit(BTRFS_INODE_DUMMY,
2011		&BTRFS_I(fs_info->btree_inode)->runtime_flags);
2012	insert_inode_hash(fs_info->btree_inode);
2013
2014	spin_lock_init(&fs_info->block_group_cache_lock);
2015	fs_info->block_group_cache_tree = RB_ROOT;
 
2016
2017	extent_io_tree_init(&fs_info->freed_extents[0],
2018			     fs_info->btree_inode->i_mapping);
2019	extent_io_tree_init(&fs_info->freed_extents[1],
2020			     fs_info->btree_inode->i_mapping);
2021	fs_info->pinned_extents = &fs_info->freed_extents[0];
2022	fs_info->do_barriers = 1;
2023
2024
2025	mutex_init(&fs_info->ordered_operations_mutex);
2026	mutex_init(&fs_info->tree_log_mutex);
2027	mutex_init(&fs_info->chunk_mutex);
2028	mutex_init(&fs_info->transaction_kthread_mutex);
2029	mutex_init(&fs_info->cleaner_mutex);
2030	mutex_init(&fs_info->volume_mutex);
2031	init_rwsem(&fs_info->extent_commit_sem);
2032	init_rwsem(&fs_info->cleanup_work_sem);
2033	init_rwsem(&fs_info->subvol_sem);
 
 
 
 
2034
2035	btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
2036	btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
2037
2038	init_waitqueue_head(&fs_info->transaction_throttle);
2039	init_waitqueue_head(&fs_info->transaction_wait);
2040	init_waitqueue_head(&fs_info->transaction_blocked_wait);
2041	init_waitqueue_head(&fs_info->async_submit_wait);
 
2042
2043	__setup_root(4096, 4096, 4096, 4096, tree_root,
2044		     fs_info, BTRFS_ROOT_TREE_OBJECTID);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2045
2046	invalidate_bdev(fs_devices->latest_bdev);
 
 
 
 
2047	bh = btrfs_read_dev_super(fs_devices->latest_bdev);
2048	if (!bh) {
 
 
 
 
 
 
 
 
 
 
 
 
2049		err = -EINVAL;
 
 
 
 
 
 
 
2050		goto fail_alloc;
2051	}
2052
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2053	memcpy(fs_info->super_copy, bh->b_data, sizeof(*fs_info->super_copy));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2054	memcpy(fs_info->super_for_commit, fs_info->super_copy,
2055	       sizeof(*fs_info->super_for_commit));
2056	brelse(bh);
2057
2058	memcpy(fs_info->fsid, fs_info->super_copy->fsid, BTRFS_FSID_SIZE);
 
 
 
 
 
2059
2060	disk_super = fs_info->super_copy;
2061	if (!btrfs_super_root(disk_super))
2062		goto fail_alloc;
2063
2064	/* check FS state, whether FS is broken. */
2065	fs_info->fs_state |= btrfs_super_flags(disk_super);
2066
2067	ret = btrfs_check_super_valid(fs_info, sb->s_flags & MS_RDONLY);
2068	if (ret) {
2069		printk(KERN_ERR "btrfs: superblock contains fatal errors\n");
2070		err = ret;
2071		goto fail_alloc;
2072	}
2073
2074	/*
2075	 * run through our array of backup supers and setup
2076	 * our ring pointer to the oldest one
2077	 */
2078	generation = btrfs_super_generation(disk_super);
2079	find_oldest_super_backup(fs_info, generation);
2080
2081	/*
2082	 * In the long term, we'll store the compression type in the super
2083	 * block, and it'll be used for per file compression control.
2084	 */
2085	fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
2086
2087	ret = btrfs_parse_options(tree_root, options);
2088	if (ret) {
2089		err = ret;
2090		goto fail_alloc;
2091	}
2092
2093	features = btrfs_super_incompat_flags(disk_super) &
2094		~BTRFS_FEATURE_INCOMPAT_SUPP;
2095	if (features) {
2096		printk(KERN_ERR "BTRFS: couldn't mount because of "
2097		       "unsupported optional features (%Lx).\n",
2098		       (unsigned long long)features);
2099		err = -EINVAL;
2100		goto fail_alloc;
2101	}
2102
2103	if (btrfs_super_leafsize(disk_super) !=
2104	    btrfs_super_nodesize(disk_super)) {
2105		printk(KERN_ERR "BTRFS: couldn't mount because metadata "
2106		       "blocksizes don't match.  node %d leaf %d\n",
2107		       btrfs_super_nodesize(disk_super),
2108		       btrfs_super_leafsize(disk_super));
2109		err = -EINVAL;
2110		goto fail_alloc;
2111	}
2112	if (btrfs_super_leafsize(disk_super) > BTRFS_MAX_METADATA_BLOCKSIZE) {
2113		printk(KERN_ERR "BTRFS: couldn't mount because metadata "
2114		       "blocksize (%d) was too large\n",
2115		       btrfs_super_leafsize(disk_super));
2116		err = -EINVAL;
2117		goto fail_alloc;
2118	}
2119
2120	features = btrfs_super_incompat_flags(disk_super);
2121	features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
2122	if (tree_root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
2123		features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
 
 
 
 
 
2124
2125	/*
2126	 * flag our filesystem as having big metadata blocks if
2127	 * they are bigger than the page size
2128	 */
2129	if (btrfs_super_leafsize(disk_super) > PAGE_CACHE_SIZE) {
2130		if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA))
2131			printk(KERN_INFO "btrfs flagging fs with big metadata feature\n");
 
2132		features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
2133	}
2134
2135	nodesize = btrfs_super_nodesize(disk_super);
2136	leafsize = btrfs_super_leafsize(disk_super);
2137	sectorsize = btrfs_super_sectorsize(disk_super);
2138	stripesize = btrfs_super_stripesize(disk_super);
 
 
 
 
 
 
 
2139
2140	/*
2141	 * mixed block groups end up with duplicate but slightly offset
2142	 * extent buffers for the same range.  It leads to corruptions
2143	 */
2144	if ((features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
2145	    (sectorsize != leafsize)) {
2146		printk(KERN_WARNING "btrfs: unequal leaf/node/sector sizes "
2147				"are not allowed for mixed block groups on %s\n",
2148				sb->s_id);
2149		goto fail_alloc;
2150	}
2151
 
 
 
 
2152	btrfs_set_super_incompat_flags(disk_super, features);
2153
2154	features = btrfs_super_compat_ro_flags(disk_super) &
2155		~BTRFS_FEATURE_COMPAT_RO_SUPP;
2156	if (!(sb->s_flags & MS_RDONLY) && features) {
2157		printk(KERN_ERR "BTRFS: couldn't mount RDWR because of "
2158		       "unsupported option features (%Lx).\n",
2159		       (unsigned long long)features);
2160		err = -EINVAL;
2161		goto fail_alloc;
2162	}
2163
2164	btrfs_init_workers(&fs_info->generic_worker,
2165			   "genwork", 1, NULL);
2166
2167	btrfs_init_workers(&fs_info->workers, "worker",
2168			   fs_info->thread_pool_size,
2169			   &fs_info->generic_worker);
2170
2171	btrfs_init_workers(&fs_info->delalloc_workers, "delalloc",
2172			   fs_info->thread_pool_size,
2173			   &fs_info->generic_worker);
2174
2175	btrfs_init_workers(&fs_info->submit_workers, "submit",
2176			   min_t(u64, fs_devices->num_devices,
2177			   fs_info->thread_pool_size),
2178			   &fs_info->generic_worker);
2179
2180	btrfs_init_workers(&fs_info->caching_workers, "cache",
2181			   2, &fs_info->generic_worker);
2182
2183	/* a higher idle thresh on the submit workers makes it much more
2184	 * likely that bios will be send down in a sane order to the
2185	 * devices
2186	 */
2187	fs_info->submit_workers.idle_thresh = 64;
2188
2189	fs_info->workers.idle_thresh = 16;
2190	fs_info->workers.ordered = 1;
2191
2192	fs_info->delalloc_workers.idle_thresh = 2;
2193	fs_info->delalloc_workers.ordered = 1;
2194
2195	btrfs_init_workers(&fs_info->fixup_workers, "fixup", 1,
2196			   &fs_info->generic_worker);
2197	btrfs_init_workers(&fs_info->endio_workers, "endio",
2198			   fs_info->thread_pool_size,
2199			   &fs_info->generic_worker);
2200	btrfs_init_workers(&fs_info->endio_meta_workers, "endio-meta",
2201			   fs_info->thread_pool_size,
2202			   &fs_info->generic_worker);
2203	btrfs_init_workers(&fs_info->endio_meta_write_workers,
2204			   "endio-meta-write", fs_info->thread_pool_size,
2205			   &fs_info->generic_worker);
2206	btrfs_init_workers(&fs_info->endio_write_workers, "endio-write",
2207			   fs_info->thread_pool_size,
2208			   &fs_info->generic_worker);
2209	btrfs_init_workers(&fs_info->endio_freespace_worker, "freespace-write",
2210			   1, &fs_info->generic_worker);
2211	btrfs_init_workers(&fs_info->delayed_workers, "delayed-meta",
2212			   fs_info->thread_pool_size,
2213			   &fs_info->generic_worker);
2214	btrfs_init_workers(&fs_info->readahead_workers, "readahead",
2215			   fs_info->thread_pool_size,
2216			   &fs_info->generic_worker);
2217
2218	/*
2219	 * endios are largely parallel and should have a very
2220	 * low idle thresh
2221	 */
2222	fs_info->endio_workers.idle_thresh = 4;
2223	fs_info->endio_meta_workers.idle_thresh = 4;
2224
2225	fs_info->endio_write_workers.idle_thresh = 2;
2226	fs_info->endio_meta_write_workers.idle_thresh = 2;
2227	fs_info->readahead_workers.idle_thresh = 2;
2228
2229	/*
2230	 * btrfs_start_workers can really only fail because of ENOMEM so just
2231	 * return -ENOMEM if any of these fail.
2232	 */
2233	ret = btrfs_start_workers(&fs_info->workers);
2234	ret |= btrfs_start_workers(&fs_info->generic_worker);
2235	ret |= btrfs_start_workers(&fs_info->submit_workers);
2236	ret |= btrfs_start_workers(&fs_info->delalloc_workers);
2237	ret |= btrfs_start_workers(&fs_info->fixup_workers);
2238	ret |= btrfs_start_workers(&fs_info->endio_workers);
2239	ret |= btrfs_start_workers(&fs_info->endio_meta_workers);
2240	ret |= btrfs_start_workers(&fs_info->endio_meta_write_workers);
2241	ret |= btrfs_start_workers(&fs_info->endio_write_workers);
2242	ret |= btrfs_start_workers(&fs_info->endio_freespace_worker);
2243	ret |= btrfs_start_workers(&fs_info->delayed_workers);
2244	ret |= btrfs_start_workers(&fs_info->caching_workers);
2245	ret |= btrfs_start_workers(&fs_info->readahead_workers);
2246	if (ret) {
2247		ret = -ENOMEM;
2248		goto fail_sb_buffer;
2249	}
2250
2251	fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
2252	fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
2253				    4 * 1024 * 1024 / PAGE_CACHE_SIZE);
2254
2255	tree_root->nodesize = nodesize;
2256	tree_root->leafsize = leafsize;
2257	tree_root->sectorsize = sectorsize;
2258	tree_root->stripesize = stripesize;
2259
2260	sb->s_blocksize = sectorsize;
2261	sb->s_blocksize_bits = blksize_bits(sectorsize);
2262
2263	if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
2264		    sizeof(disk_super->magic))) {
2265		printk(KERN_INFO "btrfs: valid FS not found on %s\n", sb->s_id);
2266		goto fail_sb_buffer;
2267	}
2268
2269	if (sectorsize != PAGE_SIZE) {
2270		printk(KERN_WARNING "btrfs: Incompatible sector size(%lu) "
2271		       "found on %s\n", (unsigned long)sectorsize, sb->s_id);
2272		goto fail_sb_buffer;
2273	}
2274
2275	mutex_lock(&fs_info->chunk_mutex);
2276	ret = btrfs_read_sys_array(tree_root);
2277	mutex_unlock(&fs_info->chunk_mutex);
2278	if (ret) {
2279		printk(KERN_WARNING "btrfs: failed to read the system "
2280		       "array on %s\n", sb->s_id);
2281		goto fail_sb_buffer;
2282	}
2283
2284	blocksize = btrfs_level_size(tree_root,
2285				     btrfs_super_chunk_root_level(disk_super));
2286	generation = btrfs_super_chunk_root_generation(disk_super);
 
2287
2288	__setup_root(nodesize, leafsize, sectorsize, stripesize,
2289		     chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
2290
2291	chunk_root->node = read_tree_block(chunk_root,
2292					   btrfs_super_chunk_root(disk_super),
2293					   blocksize, generation);
2294	BUG_ON(!chunk_root->node); /* -ENOMEM */
2295	if (!test_bit(EXTENT_BUFFER_UPTODATE, &chunk_root->node->bflags)) {
2296		printk(KERN_WARNING "btrfs: failed to read chunk root on %s\n",
2297		       sb->s_id);
 
 
2298		goto fail_tree_roots;
2299	}
2300	btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
2301	chunk_root->commit_root = btrfs_root_node(chunk_root);
2302
2303	read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
2304	   (unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
2305	   BTRFS_UUID_SIZE);
2306
2307	ret = btrfs_read_chunk_tree(chunk_root);
2308	if (ret) {
2309		printk(KERN_WARNING "btrfs: failed to read chunk tree on %s\n",
2310		       sb->s_id);
2311		goto fail_tree_roots;
2312	}
2313
2314	btrfs_close_extra_devices(fs_devices);
 
 
 
 
2315
2316	if (!fs_devices->latest_bdev) {
2317		printk(KERN_CRIT "btrfs: failed to read devices on %s\n",
2318		       sb->s_id);
2319		goto fail_tree_roots;
2320	}
2321
2322retry_root_backup:
2323	blocksize = btrfs_level_size(tree_root,
2324				     btrfs_super_root_level(disk_super));
2325	generation = btrfs_super_generation(disk_super);
 
2326
2327	tree_root->node = read_tree_block(tree_root,
2328					  btrfs_super_root(disk_super),
2329					  blocksize, generation);
2330	if (!tree_root->node ||
2331	    !test_bit(EXTENT_BUFFER_UPTODATE, &tree_root->node->bflags)) {
2332		printk(KERN_WARNING "btrfs: failed to read tree root on %s\n",
2333		       sb->s_id);
2334
 
2335		goto recovery_tree_root;
2336	}
2337
2338	btrfs_set_root_node(&tree_root->root_item, tree_root->node);
2339	tree_root->commit_root = btrfs_root_node(tree_root);
 
2340
2341	ret = find_and_setup_root(tree_root, fs_info,
2342				  BTRFS_EXTENT_TREE_OBJECTID, extent_root);
2343	if (ret)
 
 
2344		goto recovery_tree_root;
2345	extent_root->track_dirty = 1;
2346
2347	ret = find_and_setup_root(tree_root, fs_info,
2348				  BTRFS_DEV_TREE_OBJECTID, dev_root);
2349	if (ret)
2350		goto recovery_tree_root;
2351	dev_root->track_dirty = 1;
2352
2353	ret = find_and_setup_root(tree_root, fs_info,
2354				  BTRFS_CSUM_TREE_OBJECTID, csum_root);
2355	if (ret)
2356		goto recovery_tree_root;
2357	csum_root->track_dirty = 1;
2358
2359	fs_info->generation = generation;
2360	fs_info->last_trans_committed = generation;
2361
 
 
 
 
 
 
 
2362	ret = btrfs_recover_balance(fs_info);
2363	if (ret) {
2364		printk(KERN_WARNING "btrfs: failed to recover balance\n");
2365		goto fail_block_groups;
2366	}
2367
2368	ret = btrfs_init_dev_stats(fs_info);
2369	if (ret) {
2370		printk(KERN_ERR "btrfs: failed to init dev_stats: %d\n",
2371		       ret);
2372		goto fail_block_groups;
2373	}
2374
2375	ret = btrfs_init_space_info(fs_info);
2376	if (ret) {
2377		printk(KERN_ERR "Failed to initial space info: %d\n", ret);
2378		goto fail_block_groups;
2379	}
2380
2381	ret = btrfs_read_block_groups(extent_root);
 
 
2382	if (ret) {
2383		printk(KERN_ERR "Failed to read block groups: %d\n", ret);
 
2384		goto fail_block_groups;
2385	}
2386
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2387	fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
2388					       "btrfs-cleaner");
2389	if (IS_ERR(fs_info->cleaner_kthread))
2390		goto fail_block_groups;
2391
2392	fs_info->transaction_kthread = kthread_run(transaction_kthread,
2393						   tree_root,
2394						   "btrfs-transaction");
2395	if (IS_ERR(fs_info->transaction_kthread))
2396		goto fail_cleaner;
2397
2398	if (!btrfs_test_opt(tree_root, SSD) &&
2399	    !btrfs_test_opt(tree_root, NOSSD) &&
2400	    !fs_info->fs_devices->rotating) {
2401		printk(KERN_INFO "Btrfs detected SSD devices, enabling SSD "
2402		       "mode\n");
2403		btrfs_set_opt(fs_info->mount_opt, SSD);
2404	}
2405
 
 
 
 
 
 
2406#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
2407	if (btrfs_test_opt(tree_root, CHECK_INTEGRITY)) {
2408		ret = btrfsic_mount(tree_root, fs_devices,
2409				    btrfs_test_opt(tree_root,
2410					CHECK_INTEGRITY_INCLUDING_EXTENT_DATA) ?
2411				    1 : 0,
2412				    fs_info->check_integrity_print_mask);
2413		if (ret)
2414			printk(KERN_WARNING "btrfs: failed to initialize"
2415			       " integrity check module %s\n", sb->s_id);
 
2416	}
2417#endif
 
 
 
 
 
 
2418
2419	/* do not make disk changes in broken FS */
2420	if (btrfs_super_log_root(disk_super) != 0 &&
2421	    !(fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)) {
2422		u64 bytenr = btrfs_super_log_root(disk_super);
2423
2424		if (fs_devices->rw_devices == 0) {
2425			printk(KERN_WARNING "Btrfs log replay required "
2426			       "on RO media\n");
2427			err = -EIO;
2428			goto fail_trans_kthread;
2429		}
2430		blocksize =
2431		     btrfs_level_size(tree_root,
2432				      btrfs_super_log_root_level(disk_super));
2433
2434		log_tree_root = btrfs_alloc_root(fs_info);
2435		if (!log_tree_root) {
2436			err = -ENOMEM;
2437			goto fail_trans_kthread;
2438		}
2439
2440		__setup_root(nodesize, leafsize, sectorsize, stripesize,
2441			     log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
2442
2443		log_tree_root->node = read_tree_block(tree_root, bytenr,
2444						      blocksize,
2445						      generation + 1);
2446		/* returns with log_tree_root freed on success */
2447		ret = btrfs_recover_log_trees(log_tree_root);
2448		if (ret) {
2449			btrfs_error(tree_root->fs_info, ret,
2450				    "Failed to recover log tree");
2451			free_extent_buffer(log_tree_root->node);
2452			kfree(log_tree_root);
2453			goto fail_trans_kthread;
2454		}
2455
2456		if (sb->s_flags & MS_RDONLY) {
2457			ret = btrfs_commit_super(tree_root);
2458			if (ret)
2459				goto fail_trans_kthread;
2460		}
2461	}
2462
2463	ret = btrfs_find_orphan_roots(tree_root);
2464	if (ret)
2465		goto fail_trans_kthread;
2466
2467	if (!(sb->s_flags & MS_RDONLY)) {
2468		ret = btrfs_cleanup_fs_roots(fs_info);
2469		if (ret) {
2470			}
2471
 
2472		ret = btrfs_recover_relocation(tree_root);
 
2473		if (ret < 0) {
2474			printk(KERN_WARNING
2475			       "btrfs: failed to recover relocation\n");
2476			err = -EINVAL;
2477			goto fail_trans_kthread;
2478		}
2479	}
2480
2481	location.objectid = BTRFS_FS_TREE_OBJECTID;
2482	location.type = BTRFS_ROOT_ITEM_KEY;
2483	location.offset = (u64)-1;
2484
2485	fs_info->fs_root = btrfs_read_fs_root_no_name(fs_info, &location);
2486	if (!fs_info->fs_root)
2487		goto fail_trans_kthread;
2488	if (IS_ERR(fs_info->fs_root)) {
2489		err = PTR_ERR(fs_info->fs_root);
2490		goto fail_trans_kthread;
 
2491	}
2492
2493	if (sb->s_flags & MS_RDONLY)
2494		return 0;
2495
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2496	down_read(&fs_info->cleanup_work_sem);
2497	if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) ||
2498	    (ret = btrfs_orphan_cleanup(fs_info->tree_root))) {
2499		up_read(&fs_info->cleanup_work_sem);
2500		close_ctree(tree_root);
2501		return ret;
2502	}
2503	up_read(&fs_info->cleanup_work_sem);
2504
2505	ret = btrfs_resume_balance_async(fs_info);
2506	if (ret) {
2507		printk(KERN_WARNING "btrfs: failed to resume balance\n");
2508		close_ctree(tree_root);
 
 
 
 
 
 
 
2509		return ret;
2510	}
2511
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2512	return 0;
2513
 
 
2514fail_trans_kthread:
2515	kthread_stop(fs_info->transaction_kthread);
 
 
2516fail_cleaner:
2517	kthread_stop(fs_info->cleaner_kthread);
2518
2519	/*
2520	 * make sure we're done with the btree inode before we stop our
2521	 * kthreads
2522	 */
2523	filemap_write_and_wait(fs_info->btree_inode->i_mapping);
2524	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
 
 
 
 
 
2525
2526fail_block_groups:
2527	btrfs_free_block_groups(fs_info);
2528
2529fail_tree_roots:
2530	free_root_pointers(fs_info, 1);
 
2531
2532fail_sb_buffer:
2533	btrfs_stop_workers(&fs_info->generic_worker);
2534	btrfs_stop_workers(&fs_info->readahead_workers);
2535	btrfs_stop_workers(&fs_info->fixup_workers);
2536	btrfs_stop_workers(&fs_info->delalloc_workers);
2537	btrfs_stop_workers(&fs_info->workers);
2538	btrfs_stop_workers(&fs_info->endio_workers);
2539	btrfs_stop_workers(&fs_info->endio_meta_workers);
2540	btrfs_stop_workers(&fs_info->endio_meta_write_workers);
2541	btrfs_stop_workers(&fs_info->endio_write_workers);
2542	btrfs_stop_workers(&fs_info->endio_freespace_worker);
2543	btrfs_stop_workers(&fs_info->submit_workers);
2544	btrfs_stop_workers(&fs_info->delayed_workers);
2545	btrfs_stop_workers(&fs_info->caching_workers);
2546fail_alloc:
2547fail_iput:
2548	btrfs_mapping_tree_free(&fs_info->mapping_tree);
2549
2550	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
2551	iput(fs_info->btree_inode);
2552fail_bdi:
2553	bdi_destroy(&fs_info->bdi);
 
 
 
 
 
 
2554fail_srcu:
2555	cleanup_srcu_struct(&fs_info->subvol_srcu);
2556fail:
 
2557	btrfs_close_devices(fs_info->fs_devices);
2558	return err;
2559
2560recovery_tree_root:
2561	if (!btrfs_test_opt(tree_root, RECOVERY))
2562		goto fail_tree_roots;
2563
2564	free_root_pointers(fs_info, 0);
2565
2566	/* don't use the log in recovery mode, it won't be valid */
2567	btrfs_set_super_log_root(disk_super, 0);
2568
2569	/* we can't trust the free space cache either */
2570	btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
2571
2572	ret = next_root_backup(fs_info, fs_info->super_copy,
2573			       &num_backups_tried, &backup_index);
2574	if (ret == -1)
2575		goto fail_block_groups;
2576	goto retry_root_backup;
2577}
 
2578
2579static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
2580{
2581	if (uptodate) {
2582		set_buffer_uptodate(bh);
2583	} else {
2584		struct btrfs_device *device = (struct btrfs_device *)
2585			bh->b_private;
2586
2587		printk_ratelimited_in_rcu(KERN_WARNING "lost page write due to "
2588					  "I/O error on %s\n",
2589					  rcu_str_deref(device->name));
2590		/* note, we dont' set_buffer_write_io_error because we have
2591		 * our own ways of dealing with the IO errors
2592		 */
2593		clear_buffer_uptodate(bh);
2594		btrfs_dev_stat_inc_and_print(device, BTRFS_DEV_STAT_WRITE_ERRS);
2595	}
2596	unlock_buffer(bh);
2597	put_bh(bh);
2598}
2599
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2600struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
2601{
2602	struct buffer_head *bh;
2603	struct buffer_head *latest = NULL;
2604	struct btrfs_super_block *super;
2605	int i;
2606	u64 transid = 0;
2607	u64 bytenr;
2608
2609	/* we would like to check all the supers, but that would make
2610	 * a btrfs mount succeed after a mkfs from a different FS.
2611	 * So, we need to add a special mount option to scan for
2612	 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
2613	 */
2614	for (i = 0; i < 1; i++) {
2615		bytenr = btrfs_sb_offset(i);
2616		if (bytenr + 4096 >= i_size_read(bdev->bd_inode))
2617			break;
2618		bh = __bread(bdev, bytenr / 4096, 4096);
2619		if (!bh)
2620			continue;
2621
2622		super = (struct btrfs_super_block *)bh->b_data;
2623		if (btrfs_super_bytenr(super) != bytenr ||
2624		    strncmp((char *)(&super->magic), BTRFS_MAGIC,
2625			    sizeof(super->magic))) {
2626			brelse(bh);
2627			continue;
2628		}
2629
2630		if (!latest || btrfs_super_generation(super) > transid) {
2631			brelse(latest);
2632			latest = bh;
2633			transid = btrfs_super_generation(super);
2634		} else {
2635			brelse(bh);
2636		}
2637	}
 
 
 
 
2638	return latest;
2639}
2640
2641/*
2642 * this should be called twice, once with wait == 0 and
2643 * once with wait == 1.  When wait == 0 is done, all the buffer heads
2644 * we write are pinned.
2645 *
2646 * They are released when wait == 1 is done.
2647 * max_mirrors must be the same for both runs, and it indicates how
2648 * many supers on this one device should be written.
2649 *
2650 * max_mirrors == 0 means to write them all.
2651 */
2652static int write_dev_supers(struct btrfs_device *device,
2653			    struct btrfs_super_block *sb,
2654			    int do_barriers, int wait, int max_mirrors)
2655{
 
 
2656	struct buffer_head *bh;
2657	int i;
2658	int ret;
2659	int errors = 0;
2660	u32 crc;
2661	u64 bytenr;
 
2662
2663	if (max_mirrors == 0)
2664		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
2665
 
 
2666	for (i = 0; i < max_mirrors; i++) {
2667		bytenr = btrfs_sb_offset(i);
2668		if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->total_bytes)
 
2669			break;
2670
2671		if (wait) {
2672			bh = __find_get_block(device->bdev, bytenr / 4096,
2673					      BTRFS_SUPER_INFO_SIZE);
2674			BUG_ON(!bh);
2675			wait_on_buffer(bh);
2676			if (!buffer_uptodate(bh))
2677				errors++;
2678
2679			/* drop our reference */
2680			brelse(bh);
2681
2682			/* drop the reference from the wait == 0 run */
2683			brelse(bh);
 
 
 
 
 
 
 
 
2684			continue;
2685		} else {
2686			btrfs_set_super_bytenr(sb, bytenr);
2687
2688			crc = ~(u32)0;
2689			crc = btrfs_csum_data(NULL, (char *)sb +
2690					      BTRFS_CSUM_SIZE, crc,
2691					      BTRFS_SUPER_INFO_SIZE -
2692					      BTRFS_CSUM_SIZE);
2693			btrfs_csum_final(crc, sb->csum);
2694
2695			/*
2696			 * one reference for us, and we leave it for the
2697			 * caller
2698			 */
2699			bh = __getblk(device->bdev, bytenr / 4096,
2700				      BTRFS_SUPER_INFO_SIZE);
2701			memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
2702
2703			/* one reference for submit_bh */
2704			get_bh(bh);
2705
2706			set_buffer_uptodate(bh);
2707			lock_buffer(bh);
2708			bh->b_end_io = btrfs_end_buffer_write_sync;
2709			bh->b_private = device;
2710		}
2711
2712		/*
2713		 * we fua the first super.  The others we allow
2714		 * to go down lazy.
2715		 */
2716		ret = btrfsic_submit_bh(WRITE_FUA, bh);
 
 
 
2717		if (ret)
2718			errors++;
2719	}
2720	return errors < i ? 0 : -1;
2721}
2722
2723/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2724 * endio for the write_dev_flush, this will wake anyone waiting
2725 * for the barrier when it is done
2726 */
2727static void btrfs_end_empty_barrier(struct bio *bio, int err)
2728{
2729	if (err) {
2730		if (err == -EOPNOTSUPP)
2731			set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
2732		clear_bit(BIO_UPTODATE, &bio->bi_flags);
2733	}
2734	if (bio->bi_private)
2735		complete(bio->bi_private);
2736	bio_put(bio);
2737}
2738
2739/*
2740 * trigger flushes for one the devices.  If you pass wait == 0, the flushes are
2741 * sent down.  With wait == 1, it waits for the previous flush.
2742 *
2743 * any device where the flush fails with eopnotsupp are flagged as not-barrier
2744 * capable
2745 */
2746static int write_dev_flush(struct btrfs_device *device, int wait)
2747{
2748	struct bio *bio;
2749	int ret = 0;
2750
2751	if (device->nobarriers)
2752		return 0;
2753
2754	if (wait) {
2755		bio = device->flush_bio;
2756		if (!bio)
2757			return 0;
 
 
2758
2759		wait_for_completion(&device->flush_wait);
 
 
2760
2761		if (bio_flagged(bio, BIO_EOPNOTSUPP)) {
2762			printk_in_rcu("btrfs: disabling barriers on dev %s\n",
2763				      rcu_str_deref(device->name));
2764			device->nobarriers = 1;
2765		}
2766		if (!bio_flagged(bio, BIO_UPTODATE)) {
2767			ret = -EIO;
2768			if (!bio_flagged(bio, BIO_EOPNOTSUPP))
2769				btrfs_dev_stat_inc_and_print(device,
2770					BTRFS_DEV_STAT_FLUSH_ERRS);
2771		}
2772
2773		/* drop the reference from the wait == 0 run */
2774		bio_put(bio);
2775		device->flush_bio = NULL;
2776
2777		return ret;
2778	}
2779
2780	/*
2781	 * one reference for us, and we leave it for the
2782	 * caller
2783	 */
2784	device->flush_bio = NULL;
2785	bio = bio_alloc(GFP_NOFS, 0);
2786	if (!bio)
2787		return -ENOMEM;
2788
2789	bio->bi_end_io = btrfs_end_empty_barrier;
2790	bio->bi_bdev = device->bdev;
2791	init_completion(&device->flush_wait);
2792	bio->bi_private = &device->flush_wait;
2793	device->flush_bio = bio;
2794
2795	bio_get(bio);
2796	btrfsic_submit_bio(WRITE_FLUSH, bio);
2797
 
 
 
 
2798	return 0;
2799}
2800
2801/*
2802 * send an empty flush down to each device in parallel,
2803 * then wait for them
2804 */
2805static int barrier_all_devices(struct btrfs_fs_info *info)
2806{
2807	struct list_head *head;
2808	struct btrfs_device *dev;
2809	int errors = 0;
2810	int ret;
2811
 
2812	/* send down all the barriers */
2813	head = &info->fs_devices->devices;
2814	list_for_each_entry_rcu(dev, head, dev_list) {
2815		if (!dev->bdev) {
2816			errors++;
 
2817			continue;
2818		}
2819		if (!dev->in_fs_metadata || !dev->writeable)
2820			continue;
2821
2822		ret = write_dev_flush(dev, 0);
2823		if (ret)
2824			errors++;
2825	}
2826
2827	/* wait for all the barriers */
2828	list_for_each_entry_rcu(dev, head, dev_list) {
 
 
2829		if (!dev->bdev) {
2830			errors++;
2831			continue;
2832		}
2833		if (!dev->in_fs_metadata || !dev->writeable)
 
2834			continue;
2835
2836		ret = write_dev_flush(dev, 1);
2837		if (ret)
2838			errors++;
 
 
 
 
 
 
 
 
 
 
 
 
 
2839	}
2840	if (errors)
2841		return -EIO;
2842	return 0;
2843}
2844
2845int write_all_supers(struct btrfs_root *root, int max_mirrors)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2846{
2847	struct list_head *head;
2848	struct btrfs_device *dev;
2849	struct btrfs_super_block *sb;
2850	struct btrfs_dev_item *dev_item;
2851	int ret;
2852	int do_barriers;
2853	int max_errors;
2854	int total_errors = 0;
2855	u64 flags;
2856
2857	max_errors = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
2858	do_barriers = !btrfs_test_opt(root, NOBARRIER);
2859	backup_super_roots(root->fs_info);
 
 
 
 
 
 
2860
2861	sb = root->fs_info->super_for_commit;
2862	dev_item = &sb->dev_item;
2863
2864	mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2865	head = &root->fs_info->fs_devices->devices;
 
2866
2867	if (do_barriers)
2868		barrier_all_devices(root->fs_info);
 
 
 
 
 
 
 
 
2869
2870	list_for_each_entry_rcu(dev, head, dev_list) {
2871		if (!dev->bdev) {
2872			total_errors++;
2873			continue;
2874		}
2875		if (!dev->in_fs_metadata || !dev->writeable)
 
2876			continue;
2877
2878		btrfs_set_stack_device_generation(dev_item, 0);
2879		btrfs_set_stack_device_type(dev_item, dev->type);
2880		btrfs_set_stack_device_id(dev_item, dev->devid);
2881		btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
2882		btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
 
 
2883		btrfs_set_stack_device_io_align(dev_item, dev->io_align);
2884		btrfs_set_stack_device_io_width(dev_item, dev->io_width);
2885		btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
2886		memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
2887		memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
 
2888
2889		flags = btrfs_super_flags(sb);
2890		btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
2891
2892		ret = write_dev_supers(dev, sb, do_barriers, 0, max_mirrors);
 
 
 
 
 
 
 
 
2893		if (ret)
2894			total_errors++;
2895	}
2896	if (total_errors > max_errors) {
2897		printk(KERN_ERR "btrfs: %d errors while writing supers\n",
2898		       total_errors);
2899
2900		/* This shouldn't happen. FUA is masked off if unsupported */
2901		BUG();
 
 
 
 
2902	}
2903
2904	total_errors = 0;
2905	list_for_each_entry_rcu(dev, head, dev_list) {
2906		if (!dev->bdev)
2907			continue;
2908		if (!dev->in_fs_metadata || !dev->writeable)
 
2909			continue;
2910
2911		ret = write_dev_supers(dev, sb, do_barriers, 1, max_mirrors);
2912		if (ret)
2913			total_errors++;
2914	}
2915	mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2916	if (total_errors > max_errors) {
2917		btrfs_error(root->fs_info, -EIO,
2918			    "%d errors while writing supers", total_errors);
 
2919		return -EIO;
2920	}
2921	return 0;
2922}
2923
2924int write_ctree_super(struct btrfs_trans_handle *trans,
2925		      struct btrfs_root *root, int max_mirrors)
2926{
2927	int ret;
2928
2929	ret = write_all_supers(root, max_mirrors);
2930	return ret;
2931}
2932
2933void btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
2934{
2935	spin_lock(&fs_info->fs_roots_radix_lock);
2936	radix_tree_delete(&fs_info->fs_roots_radix,
2937			  (unsigned long)root->root_key.objectid);
2938	spin_unlock(&fs_info->fs_roots_radix_lock);
2939
2940	if (btrfs_root_refs(&root->root_item) == 0)
2941		synchronize_srcu(&fs_info->subvol_srcu);
2942
2943	__btrfs_remove_free_space_cache(root->free_ino_pinned);
2944	__btrfs_remove_free_space_cache(root->free_ino_ctl);
2945	free_fs_root(root);
 
 
 
 
 
 
 
 
 
 
 
 
2946}
2947
2948static void free_fs_root(struct btrfs_root *root)
2949{
2950	iput(root->cache_inode);
2951	WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
2952	if (root->anon_dev)
2953		free_anon_bdev(root->anon_dev);
 
 
2954	free_extent_buffer(root->node);
2955	free_extent_buffer(root->commit_root);
2956	kfree(root->free_ino_ctl);
2957	kfree(root->free_ino_pinned);
2958	kfree(root->name);
2959	kfree(root);
2960}
2961
2962static void del_fs_roots(struct btrfs_fs_info *fs_info)
2963{
2964	int ret;
2965	struct btrfs_root *gang[8];
2966	int i;
2967
2968	while (!list_empty(&fs_info->dead_roots)) {
2969		gang[0] = list_entry(fs_info->dead_roots.next,
2970				     struct btrfs_root, root_list);
2971		list_del(&gang[0]->root_list);
2972
2973		if (gang[0]->in_radix) {
2974			btrfs_free_fs_root(fs_info, gang[0]);
2975		} else {
2976			free_extent_buffer(gang[0]->node);
2977			free_extent_buffer(gang[0]->commit_root);
2978			kfree(gang[0]);
2979		}
2980	}
2981
2982	while (1) {
2983		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2984					     (void **)gang, 0,
2985					     ARRAY_SIZE(gang));
2986		if (!ret)
2987			break;
2988		for (i = 0; i < ret; i++)
2989			btrfs_free_fs_root(fs_info, gang[i]);
2990	}
2991}
2992
2993int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
2994{
2995	u64 root_objectid = 0;
2996	struct btrfs_root *gang[8];
2997	int i;
2998	int ret;
 
 
2999
3000	while (1) {
 
3001		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
3002					     (void **)gang, root_objectid,
3003					     ARRAY_SIZE(gang));
3004		if (!ret)
 
3005			break;
 
 
3006
3007		root_objectid = gang[ret - 1]->root_key.objectid + 1;
3008		for (i = 0; i < ret; i++) {
3009			int err;
 
 
 
 
 
 
 
 
3010
 
 
 
3011			root_objectid = gang[i]->root_key.objectid;
3012			err = btrfs_orphan_cleanup(gang[i]);
3013			if (err)
3014				return err;
 
3015		}
3016		root_objectid++;
3017	}
3018	return 0;
 
 
 
 
 
 
3019}
3020
3021int btrfs_commit_super(struct btrfs_root *root)
3022{
 
3023	struct btrfs_trans_handle *trans;
3024	int ret;
3025
3026	mutex_lock(&root->fs_info->cleaner_mutex);
3027	btrfs_run_delayed_iputs(root);
3028	btrfs_clean_old_snapshots(root);
3029	mutex_unlock(&root->fs_info->cleaner_mutex);
3030
3031	/* wait until ongoing cleanup work done */
3032	down_write(&root->fs_info->cleanup_work_sem);
3033	up_write(&root->fs_info->cleanup_work_sem);
3034
3035	trans = btrfs_join_transaction(root);
3036	if (IS_ERR(trans))
3037		return PTR_ERR(trans);
3038	ret = btrfs_commit_transaction(trans, root);
3039	if (ret)
3040		return ret;
3041	/* run commit again to drop the original snapshot */
3042	trans = btrfs_join_transaction(root);
3043	if (IS_ERR(trans))
3044		return PTR_ERR(trans);
3045	ret = btrfs_commit_transaction(trans, root);
3046	if (ret)
3047		return ret;
3048	ret = btrfs_write_and_wait_transaction(NULL, root);
3049	if (ret) {
3050		btrfs_error(root->fs_info, ret,
3051			    "Failed to sync btree inode to disk.");
3052		return ret;
3053	}
3054
3055	ret = write_ctree_super(NULL, root, 0);
3056	return ret;
3057}
3058
3059int close_ctree(struct btrfs_root *root)
3060{
3061	struct btrfs_fs_info *fs_info = root->fs_info;
3062	int ret;
3063
3064	fs_info->closing = 1;
3065	smp_mb();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3066
3067	/* pause restriper - we want to resume on mount */
3068	btrfs_pause_balance(root->fs_info);
 
 
3069
3070	btrfs_scrub_cancel(root);
3071
3072	/* wait for any defraggers to finish */
3073	wait_event(fs_info->transaction_wait,
3074		   (atomic_read(&fs_info->defrag_running) == 0));
3075
3076	/* clear out the rbtree of defraggable inodes */
3077	btrfs_run_defrag_inodes(fs_info);
3078
3079	/*
3080	 * Here come 2 situations when btrfs is broken to flip readonly:
3081	 *
3082	 * 1. when btrfs flips readonly somewhere else before
3083	 * btrfs_commit_super, sb->s_flags has MS_RDONLY flag,
3084	 * and btrfs will skip to write sb directly to keep
3085	 * ERROR state on disk.
3086	 *
3087	 * 2. when btrfs flips readonly just in btrfs_commit_super,
3088	 * and in such case, btrfs cannot write sb via btrfs_commit_super,
3089	 * and since fs_state has been set BTRFS_SUPER_FLAG_ERROR flag,
3090	 * btrfs will cleanup all FS resources first and write sb then.
3091	 */
3092	if (!(fs_info->sb->s_flags & MS_RDONLY)) {
3093		ret = btrfs_commit_super(root);
3094		if (ret)
3095			printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
3096	}
3097
3098	if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
3099		ret = btrfs_error_commit_super(root);
3100		if (ret)
3101			printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
3102	}
3103
3104	btrfs_put_block_group_cache(fs_info);
 
 
3105
3106	kthread_stop(fs_info->transaction_kthread);
3107	kthread_stop(fs_info->cleaner_kthread);
3108
3109	fs_info->closing = 2;
3110	smp_mb();
 
 
 
 
 
 
 
 
3111
3112	if (fs_info->delalloc_bytes) {
3113		printk(KERN_INFO "btrfs: at unmount delalloc count %llu\n",
3114		       (unsigned long long)fs_info->delalloc_bytes);
3115	}
3116	if (fs_info->total_ref_cache_size) {
3117		printk(KERN_INFO "btrfs: at umount reference cache size %llu\n",
3118		       (unsigned long long)fs_info->total_ref_cache_size);
3119	}
3120
3121	free_extent_buffer(fs_info->extent_root->node);
3122	free_extent_buffer(fs_info->extent_root->commit_root);
3123	free_extent_buffer(fs_info->tree_root->node);
3124	free_extent_buffer(fs_info->tree_root->commit_root);
3125	free_extent_buffer(fs_info->chunk_root->node);
3126	free_extent_buffer(fs_info->chunk_root->commit_root);
3127	free_extent_buffer(fs_info->dev_root->node);
3128	free_extent_buffer(fs_info->dev_root->commit_root);
3129	free_extent_buffer(fs_info->csum_root->node);
3130	free_extent_buffer(fs_info->csum_root->commit_root);
3131
3132	btrfs_free_block_groups(fs_info);
3133
3134	del_fs_roots(fs_info);
 
3135
3136	iput(fs_info->btree_inode);
3137
3138	btrfs_stop_workers(&fs_info->generic_worker);
3139	btrfs_stop_workers(&fs_info->fixup_workers);
3140	btrfs_stop_workers(&fs_info->delalloc_workers);
3141	btrfs_stop_workers(&fs_info->workers);
3142	btrfs_stop_workers(&fs_info->endio_workers);
3143	btrfs_stop_workers(&fs_info->endio_meta_workers);
3144	btrfs_stop_workers(&fs_info->endio_meta_write_workers);
3145	btrfs_stop_workers(&fs_info->endio_write_workers);
3146	btrfs_stop_workers(&fs_info->endio_freespace_worker);
3147	btrfs_stop_workers(&fs_info->submit_workers);
3148	btrfs_stop_workers(&fs_info->delayed_workers);
3149	btrfs_stop_workers(&fs_info->caching_workers);
3150	btrfs_stop_workers(&fs_info->readahead_workers);
3151
3152#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3153	if (btrfs_test_opt(root, CHECK_INTEGRITY))
3154		btrfsic_unmount(root, fs_info->fs_devices);
3155#endif
3156
 
3157	btrfs_close_devices(fs_info->fs_devices);
3158	btrfs_mapping_tree_free(&fs_info->mapping_tree);
3159
3160	bdi_destroy(&fs_info->bdi);
 
 
 
3161	cleanup_srcu_struct(&fs_info->subvol_srcu);
3162
3163	return 0;
 
 
3164}
3165
3166int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
3167			  int atomic)
3168{
3169	int ret;
3170	struct inode *btree_inode = buf->pages[0]->mapping->host;
3171
3172	ret = extent_buffer_uptodate(buf);
3173	if (!ret)
3174		return ret;
3175
3176	ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
3177				    parent_transid, atomic);
3178	if (ret == -EAGAIN)
3179		return ret;
3180	return !ret;
3181}
3182
3183int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
3184{
3185	return set_extent_buffer_uptodate(buf);
3186}
3187
3188void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
3189{
3190	struct btrfs_root *root = BTRFS_I(buf->pages[0]->mapping->host)->root;
 
3191	u64 transid = btrfs_header_generation(buf);
3192	int was_dirty;
3193
 
 
 
 
 
 
 
 
 
 
 
3194	btrfs_assert_tree_locked(buf);
3195	if (transid != root->fs_info->generation) {
3196		printk(KERN_CRIT "btrfs transid mismatch buffer %llu, "
3197		       "found %llu running %llu\n",
3198			(unsigned long long)buf->start,
3199			(unsigned long long)transid,
3200			(unsigned long long)root->fs_info->generation);
3201		WARN_ON(1);
3202	}
3203	was_dirty = set_extent_buffer_dirty(buf);
3204	if (!was_dirty) {
3205		spin_lock(&root->fs_info->delalloc_lock);
3206		root->fs_info->dirty_metadata_bytes += buf->len;
3207		spin_unlock(&root->fs_info->delalloc_lock);
3208	}
3209}
3210
3211void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
3212{
3213	/*
3214	 * looks as though older kernels can get into trouble with
3215	 * this code, they end up stuck in balance_dirty_pages forever
 
3216	 */
3217	u64 num_dirty;
3218	unsigned long thresh = 32 * 1024 * 1024;
3219
3220	if (current->flags & PF_MEMALLOC)
3221		return;
3222
3223	btrfs_balance_delayed_items(root);
3224
3225	num_dirty = root->fs_info->dirty_metadata_bytes;
3226
3227	if (num_dirty > thresh) {
3228		balance_dirty_pages_ratelimited_nr(
3229				   root->fs_info->btree_inode->i_mapping, 1);
3230	}
3231	return;
3232}
3233
3234void __btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
 
3235{
3236	/*
3237	 * looks as though older kernels can get into trouble with
3238	 * this code, they end up stuck in balance_dirty_pages forever
3239	 */
3240	u64 num_dirty;
3241	unsigned long thresh = 32 * 1024 * 1024;
3242
3243	if (current->flags & PF_MEMALLOC)
3244		return;
3245
3246	num_dirty = root->fs_info->dirty_metadata_bytes;
 
3247
3248	if (num_dirty > thresh) {
3249		balance_dirty_pages_ratelimited_nr(
3250				   root->fs_info->btree_inode->i_mapping, 1);
 
 
3251	}
3252	return;
3253}
3254
3255int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
3256{
3257	struct btrfs_root *root = BTRFS_I(buf->pages[0]->mapping->host)->root;
3258	return btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
3259}
3260
3261static int btree_lock_page_hook(struct page *page, void *data,
3262				void (*flush_fn)(void *))
3263{
3264	struct inode *inode = page->mapping->host;
3265	struct btrfs_root *root = BTRFS_I(inode)->root;
3266	struct extent_buffer *eb;
3267
3268	/*
3269	 * We culled this eb but the page is still hanging out on the mapping,
3270	 * carry on.
3271	 */
3272	if (!PagePrivate(page))
3273		goto out;
3274
3275	eb = (struct extent_buffer *)page->private;
3276	if (!eb) {
3277		WARN_ON(1);
3278		goto out;
3279	}
3280	if (page != eb->pages[0])
3281		goto out;
3282
3283	if (!btrfs_try_tree_write_lock(eb)) {
3284		flush_fn(data);
3285		btrfs_tree_lock(eb);
3286	}
3287	btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
3288
3289	if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
3290		spin_lock(&root->fs_info->delalloc_lock);
3291		if (root->fs_info->dirty_metadata_bytes >= eb->len)
3292			root->fs_info->dirty_metadata_bytes -= eb->len;
3293		else
3294			WARN_ON(1);
3295		spin_unlock(&root->fs_info->delalloc_lock);
3296	}
3297
3298	btrfs_tree_unlock(eb);
3299out:
3300	if (!trylock_page(page)) {
3301		flush_fn(data);
3302		lock_page(page);
3303	}
3304	return 0;
3305}
3306
3307static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
3308			      int read_only)
3309{
3310	if (btrfs_super_csum_type(fs_info->super_copy) >= ARRAY_SIZE(btrfs_csum_sizes)) {
3311		printk(KERN_ERR "btrfs: unsupported checksum algorithm\n");
3312		return -EINVAL;
3313	}
3314
3315	if (read_only)
3316		return 0;
3317
3318	if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
3319		printk(KERN_WARNING "warning: mount fs with errors, "
3320		       "running btrfsck is recommended\n");
3321	}
3322
3323	return 0;
3324}
3325
3326int btrfs_error_commit_super(struct btrfs_root *root)
3327{
3328	int ret;
3329
3330	mutex_lock(&root->fs_info->cleaner_mutex);
3331	btrfs_run_delayed_iputs(root);
3332	mutex_unlock(&root->fs_info->cleaner_mutex);
3333
3334	down_write(&root->fs_info->cleanup_work_sem);
3335	up_write(&root->fs_info->cleanup_work_sem);
3336
3337	/* cleanup FS via transaction */
3338	btrfs_cleanup_transaction(root);
3339
3340	ret = write_ctree_super(NULL, root, 0);
 
 
3341
3342	return ret;
 
3343}
3344
3345static void btrfs_destroy_ordered_operations(struct btrfs_root *root)
3346{
3347	struct btrfs_inode *btrfs_inode;
3348	struct list_head splice;
3349
3350	INIT_LIST_HEAD(&splice);
3351
3352	mutex_lock(&root->fs_info->ordered_operations_mutex);
3353	spin_lock(&root->fs_info->ordered_extent_lock);
3354
3355	list_splice_init(&root->fs_info->ordered_operations, &splice);
3356	while (!list_empty(&splice)) {
3357		btrfs_inode = list_entry(splice.next, struct btrfs_inode,
3358					 ordered_operations);
3359
3360		list_del_init(&btrfs_inode->ordered_operations);
3361
3362		btrfs_invalidate_inodes(btrfs_inode->root);
3363	}
3364
3365	spin_unlock(&root->fs_info->ordered_extent_lock);
3366	mutex_unlock(&root->fs_info->ordered_operations_mutex);
3367}
3368
3369static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
3370{
 
3371	struct list_head splice;
3372	struct btrfs_ordered_extent *ordered;
3373	struct inode *inode;
3374
3375	INIT_LIST_HEAD(&splice);
3376
3377	spin_lock(&root->fs_info->ordered_extent_lock);
3378
3379	list_splice_init(&root->fs_info->ordered_extents, &splice);
3380	while (!list_empty(&splice)) {
3381		ordered = list_entry(splice.next, struct btrfs_ordered_extent,
3382				     root_extent_list);
 
 
3383
3384		list_del_init(&ordered->root_extent_list);
3385		atomic_inc(&ordered->refs);
3386
3387		/* the inode may be getting freed (in sys_unlink path). */
3388		inode = igrab(ordered->inode);
3389
3390		spin_unlock(&root->fs_info->ordered_extent_lock);
3391		if (inode)
3392			iput(inode);
3393
3394		atomic_set(&ordered->refs, 1);
3395		btrfs_put_ordered_extent(ordered);
3396
3397		spin_lock(&root->fs_info->ordered_extent_lock);
3398	}
 
3399
3400	spin_unlock(&root->fs_info->ordered_extent_lock);
 
 
 
 
 
 
3401}
3402
3403int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
3404			       struct btrfs_root *root)
3405{
3406	struct rb_node *node;
3407	struct btrfs_delayed_ref_root *delayed_refs;
3408	struct btrfs_delayed_ref_node *ref;
3409	int ret = 0;
3410
3411	delayed_refs = &trans->delayed_refs;
3412
3413	spin_lock(&delayed_refs->lock);
3414	if (delayed_refs->num_entries == 0) {
3415		spin_unlock(&delayed_refs->lock);
3416		printk(KERN_INFO "delayed_refs has NO entry\n");
3417		return ret;
3418	}
3419
3420	while ((node = rb_first(&delayed_refs->root)) != NULL) {
3421		ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
3422
3423		atomic_set(&ref->refs, 1);
3424		if (btrfs_delayed_ref_is_head(ref)) {
3425			struct btrfs_delayed_ref_head *head;
3426
3427			head = btrfs_delayed_node_to_head(ref);
3428			if (!mutex_trylock(&head->mutex)) {
3429				atomic_inc(&ref->refs);
3430				spin_unlock(&delayed_refs->lock);
3431
3432				/* Need to wait for the delayed ref to run */
3433				mutex_lock(&head->mutex);
3434				mutex_unlock(&head->mutex);
3435				btrfs_put_delayed_ref(ref);
3436
3437				spin_lock(&delayed_refs->lock);
3438				continue;
3439			}
3440
3441			kfree(head->extent_op);
3442			delayed_refs->num_heads--;
3443			if (list_empty(&head->cluster))
3444				delayed_refs->num_heads_ready--;
3445			list_del_init(&head->cluster);
3446		}
3447		ref->in_tree = 0;
3448		rb_erase(&ref->rb_node, &delayed_refs->root);
3449		delayed_refs->num_entries--;
3450
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3451		spin_unlock(&delayed_refs->lock);
3452		btrfs_put_delayed_ref(ref);
3453
 
 
 
 
 
3454		cond_resched();
3455		spin_lock(&delayed_refs->lock);
3456	}
3457
3458	spin_unlock(&delayed_refs->lock);
3459
3460	return ret;
3461}
3462
3463static void btrfs_destroy_pending_snapshots(struct btrfs_transaction *t)
3464{
3465	struct btrfs_pending_snapshot *snapshot;
3466	struct list_head splice;
3467
3468	INIT_LIST_HEAD(&splice);
3469
3470	list_splice_init(&t->pending_snapshots, &splice);
 
3471
3472	while (!list_empty(&splice)) {
3473		snapshot = list_entry(splice.next,
3474				      struct btrfs_pending_snapshot,
3475				      list);
 
 
3476
3477		list_del_init(&snapshot->list);
3478
3479		kfree(snapshot);
 
 
 
 
 
 
 
3480	}
 
3481}
3482
3483static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
3484{
3485	struct btrfs_inode *btrfs_inode;
3486	struct list_head splice;
3487
3488	INIT_LIST_HEAD(&splice);
3489
3490	spin_lock(&root->fs_info->delalloc_lock);
3491	list_splice_init(&root->fs_info->delalloc_inodes, &splice);
3492
3493	while (!list_empty(&splice)) {
3494		btrfs_inode = list_entry(splice.next, struct btrfs_inode,
3495				    delalloc_inodes);
 
 
 
3496
3497		list_del_init(&btrfs_inode->delalloc_inodes);
 
3498
3499		btrfs_invalidate_inodes(btrfs_inode->root);
3500	}
3501
3502	spin_unlock(&root->fs_info->delalloc_lock);
3503}
3504
3505static int btrfs_destroy_marked_extents(struct btrfs_root *root,
3506					struct extent_io_tree *dirty_pages,
3507					int mark)
3508{
3509	int ret;
3510	struct page *page;
3511	struct inode *btree_inode = root->fs_info->btree_inode;
3512	struct extent_buffer *eb;
3513	u64 start = 0;
3514	u64 end;
3515	u64 offset;
3516	unsigned long index;
3517
3518	while (1) {
3519		ret = find_first_extent_bit(dirty_pages, start, &start, &end,
3520					    mark);
3521		if (ret)
3522			break;
3523
3524		clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS);
3525		while (start <= end) {
3526			index = start >> PAGE_CACHE_SHIFT;
3527			start = (u64)(index + 1) << PAGE_CACHE_SHIFT;
3528			page = find_get_page(btree_inode->i_mapping, index);
3529			if (!page)
3530				continue;
3531			offset = page_offset(page);
3532
3533			spin_lock(&dirty_pages->buffer_lock);
3534			eb = radix_tree_lookup(
3535			     &(&BTRFS_I(page->mapping->host)->io_tree)->buffer,
3536					       offset >> PAGE_CACHE_SHIFT);
3537			spin_unlock(&dirty_pages->buffer_lock);
3538			if (eb)
3539				ret = test_and_clear_bit(EXTENT_BUFFER_DIRTY,
3540							 &eb->bflags);
3541			if (PageWriteback(page))
3542				end_page_writeback(page);
3543
3544			lock_page(page);
3545			if (PageDirty(page)) {
3546				clear_page_dirty_for_io(page);
3547				spin_lock_irq(&page->mapping->tree_lock);
3548				radix_tree_tag_clear(&page->mapping->page_tree,
3549							page_index(page),
3550							PAGECACHE_TAG_DIRTY);
3551				spin_unlock_irq(&page->mapping->tree_lock);
3552			}
3553
3554			unlock_page(page);
3555			page_cache_release(page);
3556		}
3557	}
3558
3559	return ret;
3560}
3561
3562static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
3563				       struct extent_io_tree *pinned_extents)
3564{
3565	struct extent_io_tree *unpin;
3566	u64 start;
3567	u64 end;
3568	int ret;
3569	bool loop = true;
3570
3571	unpin = pinned_extents;
3572again:
3573	while (1) {
 
 
 
 
 
 
 
 
 
3574		ret = find_first_extent_bit(unpin, 0, &start, &end,
3575					    EXTENT_DIRTY);
3576		if (ret)
 
3577			break;
 
3578
3579		/* opt_discard */
3580		if (btrfs_test_opt(root, DISCARD))
3581			ret = btrfs_error_discard_extent(root, start,
3582							 end + 1 - start,
3583							 NULL);
3584
3585		clear_extent_dirty(unpin, start, end, GFP_NOFS);
3586		btrfs_error_unpin_extent_range(root, start, end);
3587		cond_resched();
3588	}
3589
3590	if (loop) {
3591		if (unpin == &root->fs_info->freed_extents[0])
3592			unpin = &root->fs_info->freed_extents[1];
3593		else
3594			unpin = &root->fs_info->freed_extents[0];
3595		loop = false;
3596		goto again;
3597	}
3598
3599	return 0;
3600}
3601
3602void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
3603				   struct btrfs_root *root)
3604{
3605	btrfs_destroy_delayed_refs(cur_trans, root);
3606	btrfs_block_rsv_release(root, &root->fs_info->trans_block_rsv,
3607				cur_trans->dirty_pages.dirty_bytes);
3608
3609	/* FIXME: cleanup wait for commit */
3610	cur_trans->in_commit = 1;
3611	cur_trans->blocked = 1;
3612	wake_up(&root->fs_info->transaction_blocked_wait);
 
 
 
 
 
3613
3614	cur_trans->blocked = 0;
3615	wake_up(&root->fs_info->transaction_wait);
 
 
3616
3617	cur_trans->commit_done = 1;
3618	wake_up(&cur_trans->commit_wait);
 
 
 
 
 
 
 
 
 
 
3619
3620	btrfs_destroy_delayed_inodes(root);
3621	btrfs_assert_delayed_root_empty(root);
3622
3623	btrfs_destroy_pending_snapshots(cur_trans);
3624
3625	btrfs_destroy_marked_extents(root, &cur_trans->dirty_pages,
3626				     EXTENT_DIRTY);
3627	btrfs_destroy_pinned_extent(root,
3628				    root->fs_info->pinned_extents);
 
 
3629
3630	/*
3631	memset(cur_trans, 0, sizeof(*cur_trans));
3632	kmem_cache_free(btrfs_transaction_cachep, cur_trans);
3633	*/
 
 
 
 
 
 
 
 
 
 
 
3634}
3635
3636int btrfs_cleanup_transaction(struct btrfs_root *root)
 
3637{
3638	struct btrfs_transaction *t;
3639	LIST_HEAD(list);
3640
3641	mutex_lock(&root->fs_info->transaction_kthread_mutex);
 
 
3642
3643	spin_lock(&root->fs_info->trans_lock);
3644	list_splice_init(&root->fs_info->trans_list, &list);
3645	root->fs_info->trans_no_join = 1;
3646	spin_unlock(&root->fs_info->trans_lock);
3647
3648	while (!list_empty(&list)) {
3649		t = list_entry(list.next, struct btrfs_transaction, list);
3650		if (!t)
3651			break;
3652
3653		btrfs_destroy_ordered_operations(root);
3654
3655		btrfs_destroy_ordered_extents(root);
 
3656
3657		btrfs_destroy_delayed_refs(t, root);
 
3658
3659		btrfs_block_rsv_release(root,
3660					&root->fs_info->trans_block_rsv,
3661					t->dirty_pages.dirty_bytes);
3662
3663		/* FIXME: cleanup wait for commit */
3664		t->in_commit = 1;
3665		t->blocked = 1;
3666		if (waitqueue_active(&root->fs_info->transaction_blocked_wait))
3667			wake_up(&root->fs_info->transaction_blocked_wait);
3668
3669		t->blocked = 0;
3670		if (waitqueue_active(&root->fs_info->transaction_wait))
3671			wake_up(&root->fs_info->transaction_wait);
3672
3673		t->commit_done = 1;
3674		if (waitqueue_active(&t->commit_wait))
3675			wake_up(&t->commit_wait);
3676
3677		btrfs_destroy_delayed_inodes(root);
3678		btrfs_assert_delayed_root_empty(root);
 
 
3679
3680		btrfs_destroy_pending_snapshots(t);
 
 
3681
3682		btrfs_destroy_delalloc_inodes(root);
 
 
3683
3684		spin_lock(&root->fs_info->trans_lock);
3685		root->fs_info->running_transaction = NULL;
3686		spin_unlock(&root->fs_info->trans_lock);
3687
3688		btrfs_destroy_marked_extents(root, &t->dirty_pages,
3689					     EXTENT_DIRTY);
3690
3691		btrfs_destroy_pinned_extent(root,
3692					    root->fs_info->pinned_extents);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3693
3694		atomic_set(&t->use_count, 0);
 
 
3695		list_del_init(&t->list);
3696		memset(t, 0, sizeof(*t));
3697		kmem_cache_free(btrfs_transaction_cachep, t);
3698	}
3699
3700	spin_lock(&root->fs_info->trans_lock);
3701	root->fs_info->trans_no_join = 0;
3702	spin_unlock(&root->fs_info->trans_lock);
3703	mutex_unlock(&root->fs_info->transaction_kthread_mutex);
 
 
 
 
 
 
 
3704
3705	return 0;
3706}
3707
3708static struct extent_io_ops btree_extent_io_ops = {
3709	.write_cache_pages_lock_hook = btree_lock_page_hook,
 
3710	.readpage_end_io_hook = btree_readpage_end_io_hook,
3711	.readpage_io_failed_hook = btree_io_failed_hook,
3712	.submit_bio_hook = btree_submit_bio_hook,
3713	/* note we're sharing with inode.c for the merge bio hook */
3714	.merge_bio_hook = btrfs_merge_bio_hook,
3715};