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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};
v4.6
 
   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/slab.h>
  29#include <linux/migrate.h>
  30#include <linux/ratelimit.h>
  31#include <linux/uuid.h>
  32#include <linux/semaphore.h>
 
 
 
  33#include <asm/unaligned.h>
 
  34#include "ctree.h"
  35#include "disk-io.h"
  36#include "hash.h"
  37#include "transaction.h"
  38#include "btrfs_inode.h"
  39#include "volumes.h"
  40#include "print-tree.h"
  41#include "locking.h"
  42#include "tree-log.h"
  43#include "free-space-cache.h"
  44#include "free-space-tree.h"
  45#include "inode-map.h"
  46#include "check-integrity.h"
  47#include "rcu-string.h"
  48#include "dev-replace.h"
  49#include "raid56.h"
  50#include "sysfs.h"
  51#include "qgroup.h"
  52#include "compression.h"
  53
  54#ifdef CONFIG_X86
  55#include <asm/cpufeature.h>
  56#endif
  57
  58#define BTRFS_SUPER_FLAG_SUPP	(BTRFS_HEADER_FLAG_WRITTEN |\
  59				 BTRFS_HEADER_FLAG_RELOC |\
  60				 BTRFS_SUPER_FLAG_ERROR |\
  61				 BTRFS_SUPER_FLAG_SEEDING |\
  62				 BTRFS_SUPER_FLAG_METADUMP)
 
  63
  64static const struct extent_io_ops btree_extent_io_ops;
  65static void end_workqueue_fn(struct btrfs_work *work);
  66static void free_fs_root(struct btrfs_root *root);
  67static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
  68				    int read_only);
  69static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
  70static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
  71				      struct btrfs_root *root);
  72static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
  73static int btrfs_destroy_marked_extents(struct btrfs_root *root,
  74					struct extent_io_tree *dirty_pages,
  75					int mark);
  76static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
  77				       struct extent_io_tree *pinned_extents);
  78static int btrfs_cleanup_transaction(struct btrfs_root *root);
  79static void btrfs_error_commit_super(struct btrfs_root *root);
  80
  81/*
  82 * btrfs_end_io_wq structs are used to do processing in task context when an IO
  83 * is complete.  This is used during reads to verify checksums, and it is used
  84 * by writes to insert metadata for new file extents after IO is complete.
  85 */
  86struct btrfs_end_io_wq {
  87	struct bio *bio;
  88	bio_end_io_t *end_io;
  89	void *private;
  90	struct btrfs_fs_info *info;
  91	int error;
  92	enum btrfs_wq_endio_type metadata;
  93	struct list_head list;
  94	struct btrfs_work work;
  95};
  96
  97static struct kmem_cache *btrfs_end_io_wq_cache;
  98
  99int __init btrfs_end_io_wq_init(void)
 100{
 101	btrfs_end_io_wq_cache = kmem_cache_create("btrfs_end_io_wq",
 102					sizeof(struct btrfs_end_io_wq),
 103					0,
 104					SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
 105					NULL);
 106	if (!btrfs_end_io_wq_cache)
 107		return -ENOMEM;
 108	return 0;
 109}
 110
 111void btrfs_end_io_wq_exit(void)
 112{
 113	kmem_cache_destroy(btrfs_end_io_wq_cache);
 114}
 115
 116/*
 117 * async submit bios are used to offload expensive checksumming
 118 * onto the worker threads.  They checksum file and metadata bios
 119 * just before they are sent down the IO stack.
 120 */
 121struct async_submit_bio {
 122	struct inode *inode;
 123	struct bio *bio;
 124	struct list_head list;
 125	extent_submit_bio_hook_t *submit_bio_start;
 126	extent_submit_bio_hook_t *submit_bio_done;
 127	int rw;
 128	int mirror_num;
 129	unsigned long bio_flags;
 130	/*
 131	 * bio_offset is optional, can be used if the pages in the bio
 132	 * can't tell us where in the file the bio should go
 133	 */
 134	u64 bio_offset;
 135	struct btrfs_work work;
 136	int error;
 137};
 138
 139/*
 140 * Lockdep class keys for extent_buffer->lock's in this root.  For a given
 141 * eb, the lockdep key is determined by the btrfs_root it belongs to and
 142 * the level the eb occupies in the tree.
 143 *
 144 * Different roots are used for different purposes and may nest inside each
 145 * other and they require separate keysets.  As lockdep keys should be
 146 * static, assign keysets according to the purpose of the root as indicated
 147 * by btrfs_root->objectid.  This ensures that all special purpose roots
 148 * have separate keysets.
 149 *
 150 * Lock-nesting across peer nodes is always done with the immediate parent
 151 * node locked thus preventing deadlock.  As lockdep doesn't know this, use
 152 * subclass to avoid triggering lockdep warning in such cases.
 153 *
 154 * The key is set by the readpage_end_io_hook after the buffer has passed
 155 * csum validation but before the pages are unlocked.  It is also set by
 156 * btrfs_init_new_buffer on freshly allocated blocks.
 157 *
 158 * We also add a check to make sure the highest level of the tree is the
 159 * same as our lockdep setup here.  If BTRFS_MAX_LEVEL changes, this code
 160 * needs update as well.
 161 */
 162#ifdef CONFIG_DEBUG_LOCK_ALLOC
 163# if BTRFS_MAX_LEVEL != 8
 164#  error
 165# endif
 166
 167static struct btrfs_lockdep_keyset {
 168	u64			id;		/* root objectid */
 169	const char		*name_stem;	/* lock name stem */
 170	char			names[BTRFS_MAX_LEVEL + 1][20];
 171	struct lock_class_key	keys[BTRFS_MAX_LEVEL + 1];
 172} btrfs_lockdep_keysets[] = {
 173	{ .id = BTRFS_ROOT_TREE_OBJECTID,	.name_stem = "root"	},
 174	{ .id = BTRFS_EXTENT_TREE_OBJECTID,	.name_stem = "extent"	},
 175	{ .id = BTRFS_CHUNK_TREE_OBJECTID,	.name_stem = "chunk"	},
 176	{ .id = BTRFS_DEV_TREE_OBJECTID,	.name_stem = "dev"	},
 177	{ .id = BTRFS_FS_TREE_OBJECTID,		.name_stem = "fs"	},
 178	{ .id = BTRFS_CSUM_TREE_OBJECTID,	.name_stem = "csum"	},
 179	{ .id = BTRFS_QUOTA_TREE_OBJECTID,	.name_stem = "quota"	},
 180	{ .id = BTRFS_TREE_LOG_OBJECTID,	.name_stem = "log"	},
 181	{ .id = BTRFS_TREE_RELOC_OBJECTID,	.name_stem = "treloc"	},
 182	{ .id = BTRFS_DATA_RELOC_TREE_OBJECTID,	.name_stem = "dreloc"	},
 183	{ .id = BTRFS_UUID_TREE_OBJECTID,	.name_stem = "uuid"	},
 184	{ .id = BTRFS_FREE_SPACE_TREE_OBJECTID,	.name_stem = "free-space" },
 185	{ .id = 0,				.name_stem = "tree"	},
 186};
 187
 188void __init btrfs_init_lockdep(void)
 189{
 190	int i, j;
 191
 192	/* initialize lockdep class names */
 193	for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) {
 194		struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i];
 195
 196		for (j = 0; j < ARRAY_SIZE(ks->names); j++)
 197			snprintf(ks->names[j], sizeof(ks->names[j]),
 198				 "btrfs-%s-%02d", ks->name_stem, j);
 199	}
 200}
 201
 202void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
 203				    int level)
 204{
 205	struct btrfs_lockdep_keyset *ks;
 206
 207	BUG_ON(level >= ARRAY_SIZE(ks->keys));
 208
 209	/* find the matching keyset, id 0 is the default entry */
 210	for (ks = btrfs_lockdep_keysets; ks->id; ks++)
 211		if (ks->id == objectid)
 212			break;
 213
 214	lockdep_set_class_and_name(&eb->lock,
 215				   &ks->keys[level], ks->names[level]);
 216}
 217
 218#endif
 219
 220/*
 221 * extents on the btree inode are pretty simple, there's one extent
 222 * that covers the entire device
 223 */
 224static struct extent_map *btree_get_extent(struct inode *inode,
 225		struct page *page, size_t pg_offset, u64 start, u64 len,
 226		int create)
 227{
 228	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 
 229	struct extent_map *em;
 230	int ret;
 231
 232	read_lock(&em_tree->lock);
 233	em = lookup_extent_mapping(em_tree, start, len);
 234	if (em) {
 235		em->bdev =
 236			BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
 237		read_unlock(&em_tree->lock);
 238		goto out;
 239	}
 240	read_unlock(&em_tree->lock);
 241
 242	em = alloc_extent_map();
 243	if (!em) {
 244		em = ERR_PTR(-ENOMEM);
 245		goto out;
 246	}
 247	em->start = 0;
 248	em->len = (u64)-1;
 249	em->block_len = (u64)-1;
 250	em->block_start = 0;
 251	em->bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
 252
 253	write_lock(&em_tree->lock);
 254	ret = add_extent_mapping(em_tree, em, 0);
 255	if (ret == -EEXIST) {
 256		free_extent_map(em);
 257		em = lookup_extent_mapping(em_tree, start, len);
 258		if (!em)
 259			em = ERR_PTR(-EIO);
 260	} else if (ret) {
 261		free_extent_map(em);
 262		em = ERR_PTR(ret);
 263	}
 264	write_unlock(&em_tree->lock);
 265
 266out:
 267	return em;
 268}
 269
 270u32 btrfs_csum_data(char *data, u32 seed, size_t len)
 271{
 272	return btrfs_crc32c(seed, data, len);
 273}
 274
 275void btrfs_csum_final(u32 crc, char *result)
 276{
 277	put_unaligned_le32(~crc, result);
 278}
 279
 280/*
 281 * compute the csum for a btree block, and either verify it or write it
 282 * into the csum field of the block.
 
 283 */
 284static int csum_tree_block(struct btrfs_fs_info *fs_info,
 285			   struct extent_buffer *buf,
 286			   int verify)
 287{
 288	u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
 289	char *result = NULL;
 290	unsigned long len;
 291	unsigned long cur_len;
 292	unsigned long offset = BTRFS_CSUM_SIZE;
 293	char *kaddr;
 294	unsigned long map_start;
 295	unsigned long map_len;
 296	int err;
 297	u32 crc = ~(u32)0;
 298	unsigned long inline_result;
 
 299
 300	len = buf->len - offset;
 
 301	while (len > 0) {
 
 
 
 
 
 
 302		err = map_private_extent_buffer(buf, offset, 32,
 303					&kaddr, &map_start, &map_len);
 304		if (err)
 305			return err;
 306		cur_len = min(len, map_len - (offset - map_start));
 307		crc = btrfs_csum_data(kaddr + offset - map_start,
 308				      crc, cur_len);
 309		len -= cur_len;
 310		offset += cur_len;
 311	}
 312	if (csum_size > sizeof(inline_result)) {
 313		result = kzalloc(csum_size, GFP_NOFS);
 314		if (!result)
 315			return -ENOMEM;
 316	} else {
 317		result = (char *)&inline_result;
 318	}
 319
 320	btrfs_csum_final(crc, result);
 321
 322	if (verify) {
 323		if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
 324			u32 val;
 325			u32 found = 0;
 326			memcpy(&found, result, csum_size);
 327
 328			read_extent_buffer(buf, &val, 0, csum_size);
 329			btrfs_warn_rl(fs_info,
 330				"%s checksum verify failed on %llu wanted %X found %X "
 331				"level %d",
 332				fs_info->sb->s_id, buf->start,
 333				val, found, btrfs_header_level(buf));
 334			if (result != (char *)&inline_result)
 335				kfree(result);
 336			return -EUCLEAN;
 337		}
 338	} else {
 339		write_extent_buffer(buf, result, 0, csum_size);
 340	}
 341	if (result != (char *)&inline_result)
 342		kfree(result);
 343	return 0;
 344}
 345
 346/*
 347 * we can't consider a given block up to date unless the transid of the
 348 * block matches the transid in the parent node's pointer.  This is how we
 349 * detect blocks that either didn't get written at all or got written
 350 * in the wrong place.
 351 */
 352static int verify_parent_transid(struct extent_io_tree *io_tree,
 353				 struct extent_buffer *eb, u64 parent_transid,
 354				 int atomic)
 355{
 356	struct extent_state *cached_state = NULL;
 357	int ret;
 358	bool need_lock = (current->journal_info == BTRFS_SEND_TRANS_STUB);
 359
 360	if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 361		return 0;
 362
 363	if (atomic)
 364		return -EAGAIN;
 365
 366	if (need_lock) {
 367		btrfs_tree_read_lock(eb);
 368		btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
 369	}
 370
 371	lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
 372			 &cached_state);
 373	if (extent_buffer_uptodate(eb) &&
 374	    btrfs_header_generation(eb) == parent_transid) {
 375		ret = 0;
 376		goto out;
 377	}
 378	btrfs_err_rl(eb->fs_info,
 379		"parent transid verify failed on %llu wanted %llu found %llu",
 380			eb->start,
 381			parent_transid, btrfs_header_generation(eb));
 382	ret = 1;
 383
 384	/*
 385	 * Things reading via commit roots that don't have normal protection,
 386	 * like send, can have a really old block in cache that may point at a
 387	 * block that has been free'd and re-allocated.  So don't clear uptodate
 388	 * if we find an eb that is under IO (dirty/writeback) because we could
 389	 * end up reading in the stale data and then writing it back out and
 390	 * making everybody very sad.
 391	 */
 392	if (!extent_buffer_under_io(eb))
 393		clear_extent_buffer_uptodate(eb);
 394out:
 395	unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
 396			     &cached_state, GFP_NOFS);
 397	if (need_lock)
 398		btrfs_tree_read_unlock_blocking(eb);
 399	return ret;
 400}
 401
 
 
 
 
 
 
 
 
 
 
 402/*
 403 * Return 0 if the superblock checksum type matches the checksum value of that
 404 * algorithm. Pass the raw disk superblock data.
 405 */
 406static int btrfs_check_super_csum(char *raw_disk_sb)
 
 407{
 408	struct btrfs_super_block *disk_sb =
 409		(struct btrfs_super_block *)raw_disk_sb;
 410	u16 csum_type = btrfs_super_csum_type(disk_sb);
 411	int ret = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 412
 413	if (csum_type == BTRFS_CSUM_TYPE_CRC32) {
 414		u32 crc = ~(u32)0;
 415		const int csum_size = sizeof(crc);
 416		char result[csum_size];
 417
 418		/*
 419		 * The super_block structure does not span the whole
 420		 * BTRFS_SUPER_INFO_SIZE range, we expect that the unused space
 421		 * is filled with zeros and is included in the checkum.
 422		 */
 423		crc = btrfs_csum_data(raw_disk_sb + BTRFS_CSUM_SIZE,
 424				crc, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
 425		btrfs_csum_final(crc, result);
 426
 427		if (memcmp(raw_disk_sb, result, csum_size))
 428			ret = 1;
 
 
 
 
 
 
 429	}
 430
 431	if (csum_type >= ARRAY_SIZE(btrfs_csum_sizes)) {
 432		printk(KERN_ERR "BTRFS: unsupported checksum algorithm %u\n",
 433				csum_type);
 434		ret = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 435	}
 436
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 437	return ret;
 438}
 439
 440/*
 441 * helper to read a given tree block, doing retries as required when
 442 * the checksums don't match and we have alternate mirrors to try.
 
 
 
 
 443 */
 444static int btree_read_extent_buffer_pages(struct btrfs_root *root,
 445					  struct extent_buffer *eb,
 446					  u64 start, u64 parent_transid)
 447{
 
 448	struct extent_io_tree *io_tree;
 449	int failed = 0;
 450	int ret;
 451	int num_copies = 0;
 452	int mirror_num = 0;
 453	int failed_mirror = 0;
 454
 455	clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 456	io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
 457	while (1) {
 458		ret = read_extent_buffer_pages(io_tree, eb, start,
 459					       WAIT_COMPLETE,
 460					       btree_get_extent, mirror_num);
 461		if (!ret) {
 462			if (!verify_parent_transid(io_tree, eb,
 463						   parent_transid, 0))
 
 
 
 
 
 464				break;
 465			else
 466				ret = -EIO;
 467		}
 468
 469		/*
 470		 * This buffer's crc is fine, but its contents are corrupted, so
 471		 * there is no reason to read the other copies, they won't be
 472		 * any less wrong.
 473		 */
 474		if (test_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags))
 475			break;
 476
 477		num_copies = btrfs_num_copies(root->fs_info,
 478					      eb->start, eb->len);
 479		if (num_copies == 1)
 480			break;
 481
 482		if (!failed_mirror) {
 483			failed = 1;
 484			failed_mirror = eb->read_mirror;
 485		}
 486
 487		mirror_num++;
 488		if (mirror_num == failed_mirror)
 489			mirror_num++;
 490
 491		if (mirror_num > num_copies)
 492			break;
 493	}
 494
 495	if (failed && !ret && failed_mirror)
 496		repair_eb_io_failure(root, eb, failed_mirror);
 497
 498	return ret;
 499}
 500
 501/*
 502 * checksum a dirty tree block before IO.  This has extra checks to make sure
 503 * we only fill in the checksum field in the first page of a multi-page block
 504 */
 505
 506static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct page *page)
 507{
 508	u64 start = page_offset(page);
 509	u64 found_start;
 
 
 510	struct extent_buffer *eb;
 
 511
 512	eb = (struct extent_buffer *)page->private;
 513	if (page != eb->pages[0])
 514		return 0;
 515
 516	found_start = btrfs_header_bytenr(eb);
 517	/*
 518	 * Please do not consolidate these warnings into a single if.
 519	 * It is useful to know what went wrong.
 520	 */
 521	if (WARN_ON(found_start != start))
 522		return -EUCLEAN;
 523	if (WARN_ON(!PageUptodate(page)))
 524		return -EUCLEAN;
 525
 526	ASSERT(memcmp_extent_buffer(eb, fs_info->fsid,
 527			btrfs_header_fsid(), BTRFS_FSID_SIZE) == 0);
 528
 529	return csum_tree_block(fs_info, eb, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 530}
 531
 532static int check_tree_block_fsid(struct btrfs_fs_info *fs_info,
 533				 struct extent_buffer *eb)
 534{
 
 535	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
 536	u8 fsid[BTRFS_UUID_SIZE];
 537	int ret = 1;
 538
 539	read_extent_buffer(eb, fsid, btrfs_header_fsid(), BTRFS_FSID_SIZE);
 540	while (fs_devices) {
 541		if (!memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE)) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 542			ret = 0;
 543			break;
 544		}
 545		fs_devices = fs_devices->seed;
 546	}
 547	return ret;
 548}
 549
 550#define CORRUPT(reason, eb, root, slot)				\
 551	btrfs_crit(root->fs_info, "corrupt leaf, %s: block=%llu,"	\
 552		   "root=%llu, slot=%d", reason,			\
 553	       btrfs_header_bytenr(eb),	root->objectid, slot)
 554
 555static noinline int check_leaf(struct btrfs_root *root,
 556			       struct extent_buffer *leaf)
 557{
 558	struct btrfs_key key;
 559	struct btrfs_key leaf_key;
 560	u32 nritems = btrfs_header_nritems(leaf);
 561	int slot;
 562
 563	if (nritems == 0)
 564		return 0;
 565
 566	/* Check the 0 item */
 567	if (btrfs_item_offset_nr(leaf, 0) + btrfs_item_size_nr(leaf, 0) !=
 568	    BTRFS_LEAF_DATA_SIZE(root)) {
 569		CORRUPT("invalid item offset size pair", leaf, root, 0);
 570		return -EIO;
 571	}
 572
 573	/*
 574	 * Check to make sure each items keys are in the correct order and their
 575	 * offsets make sense.  We only have to loop through nritems-1 because
 576	 * we check the current slot against the next slot, which verifies the
 577	 * next slot's offset+size makes sense and that the current's slot
 578	 * offset is correct.
 579	 */
 580	for (slot = 0; slot < nritems - 1; slot++) {
 581		btrfs_item_key_to_cpu(leaf, &leaf_key, slot);
 582		btrfs_item_key_to_cpu(leaf, &key, slot + 1);
 583
 584		/* Make sure the keys are in the right order */
 585		if (btrfs_comp_cpu_keys(&leaf_key, &key) >= 0) {
 586			CORRUPT("bad key order", leaf, root, slot);
 587			return -EIO;
 588		}
 589
 590		/*
 591		 * Make sure the offset and ends are right, remember that the
 592		 * item data starts at the end of the leaf and grows towards the
 593		 * front.
 594		 */
 595		if (btrfs_item_offset_nr(leaf, slot) !=
 596			btrfs_item_end_nr(leaf, slot + 1)) {
 597			CORRUPT("slot offset bad", leaf, root, slot);
 598			return -EIO;
 599		}
 600
 601		/*
 602		 * Check to make sure that we don't point outside of the leaf,
 603		 * just incase all the items are consistent to eachother, but
 604		 * all point outside of the leaf.
 605		 */
 606		if (btrfs_item_end_nr(leaf, slot) >
 607		    BTRFS_LEAF_DATA_SIZE(root)) {
 608			CORRUPT("slot end outside of leaf", leaf, root, slot);
 609			return -EIO;
 610		}
 611	}
 612
 613	return 0;
 614}
 615
 616static int btree_readpage_end_io_hook(struct btrfs_io_bio *io_bio,
 617				      u64 phy_offset, struct page *page,
 618				      u64 start, u64 end, int mirror)
 619{
 620	u64 found_start;
 621	int found_level;
 622	struct extent_buffer *eb;
 623	struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 624	struct btrfs_fs_info *fs_info = root->fs_info;
 
 625	int ret = 0;
 
 626	int reads_done;
 627
 628	if (!page->private)
 629		goto out;
 630
 631	eb = (struct extent_buffer *)page->private;
 632
 633	/* the pending IO might have been the only thing that kept this buffer
 634	 * in memory.  Make sure we have a ref for all this other checks
 635	 */
 636	extent_buffer_get(eb);
 637
 638	reads_done = atomic_dec_and_test(&eb->io_pages);
 639	if (!reads_done)
 640		goto err;
 641
 642	eb->read_mirror = mirror;
 643	if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
 644		ret = -EIO;
 645		goto err;
 646	}
 647
 648	found_start = btrfs_header_bytenr(eb);
 649	if (found_start != eb->start) {
 650		btrfs_err_rl(fs_info, "bad tree block start %llu %llu",
 651			     found_start, eb->start);
 652		ret = -EIO;
 653		goto err;
 654	}
 655	if (check_tree_block_fsid(fs_info, eb)) {
 656		btrfs_err_rl(fs_info, "bad fsid on block %llu",
 657			     eb->start);
 658		ret = -EIO;
 659		goto err;
 660	}
 661	found_level = btrfs_header_level(eb);
 662	if (found_level >= BTRFS_MAX_LEVEL) {
 663		btrfs_err(fs_info, "bad tree block level %d",
 664			  (int)btrfs_header_level(eb));
 665		ret = -EIO;
 666		goto err;
 667	}
 668
 669	btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb),
 670				       eb, found_level);
 671
 672	ret = csum_tree_block(fs_info, eb, 1);
 673	if (ret)
 674		goto err;
 675
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 676	/*
 677	 * If this is a leaf block and it is corrupt, set the corrupt bit so
 678	 * that we don't try and read the other copies of this block, just
 679	 * return -EIO.
 680	 */
 681	if (found_level == 0 && check_leaf(root, eb)) {
 682		set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 683		ret = -EIO;
 684	}
 685
 
 
 
 686	if (!ret)
 687		set_extent_buffer_uptodate(eb);
 
 
 
 
 688err:
 689	if (reads_done &&
 690	    test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
 691		btree_readahead_hook(fs_info, eb, eb->start, ret);
 692
 693	if (ret) {
 694		/*
 695		 * our io error hook is going to dec the io pages
 696		 * again, we have to make sure it has something
 697		 * to decrement
 698		 */
 699		atomic_inc(&eb->io_pages);
 700		clear_extent_buffer_uptodate(eb);
 701	}
 702	free_extent_buffer(eb);
 703out:
 704	return ret;
 705}
 706
 707static int btree_io_failed_hook(struct page *page, int failed_mirror)
 708{
 709	struct extent_buffer *eb;
 710
 711	eb = (struct extent_buffer *)page->private;
 712	set_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags);
 713	eb->read_mirror = failed_mirror;
 714	atomic_dec(&eb->io_pages);
 715	if (test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
 716		btree_readahead_hook(eb->fs_info, eb, eb->start, -EIO);
 717	return -EIO;	/* we fixed nothing */
 718}
 719
 720static void end_workqueue_bio(struct bio *bio)
 721{
 722	struct btrfs_end_io_wq *end_io_wq = bio->bi_private;
 723	struct btrfs_fs_info *fs_info;
 724	struct btrfs_workqueue *wq;
 725	btrfs_work_func_t func;
 726
 727	fs_info = end_io_wq->info;
 728	end_io_wq->error = bio->bi_error;
 729
 730	if (bio->bi_rw & REQ_WRITE) {
 731		if (end_io_wq->metadata == BTRFS_WQ_ENDIO_METADATA) {
 732			wq = fs_info->endio_meta_write_workers;
 733			func = btrfs_endio_meta_write_helper;
 734		} else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_FREE_SPACE) {
 735			wq = fs_info->endio_freespace_worker;
 736			func = btrfs_freespace_write_helper;
 737		} else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56) {
 738			wq = fs_info->endio_raid56_workers;
 739			func = btrfs_endio_raid56_helper;
 740		} else {
 741			wq = fs_info->endio_write_workers;
 742			func = btrfs_endio_write_helper;
 743		}
 744	} else {
 745		if (unlikely(end_io_wq->metadata ==
 746			     BTRFS_WQ_ENDIO_DIO_REPAIR)) {
 747			wq = fs_info->endio_repair_workers;
 748			func = btrfs_endio_repair_helper;
 749		} else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56) {
 750			wq = fs_info->endio_raid56_workers;
 751			func = btrfs_endio_raid56_helper;
 752		} else if (end_io_wq->metadata) {
 753			wq = fs_info->endio_meta_workers;
 754			func = btrfs_endio_meta_helper;
 755		} else {
 756			wq = fs_info->endio_workers;
 757			func = btrfs_endio_helper;
 758		}
 759	}
 760
 761	btrfs_init_work(&end_io_wq->work, func, end_workqueue_fn, NULL, NULL);
 762	btrfs_queue_work(wq, &end_io_wq->work);
 763}
 764
 765int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
 766			enum btrfs_wq_endio_type metadata)
 767{
 768	struct btrfs_end_io_wq *end_io_wq;
 769
 770	end_io_wq = kmem_cache_alloc(btrfs_end_io_wq_cache, GFP_NOFS);
 771	if (!end_io_wq)
 772		return -ENOMEM;
 773
 774	end_io_wq->private = bio->bi_private;
 775	end_io_wq->end_io = bio->bi_end_io;
 776	end_io_wq->info = info;
 777	end_io_wq->error = 0;
 778	end_io_wq->bio = bio;
 779	end_io_wq->metadata = metadata;
 780
 781	bio->bi_private = end_io_wq;
 782	bio->bi_end_io = end_workqueue_bio;
 783	return 0;
 784}
 785
 786unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info)
 787{
 788	unsigned long limit = min_t(unsigned long,
 789				    info->thread_pool_size,
 790				    info->fs_devices->open_devices);
 791	return 256 * limit;
 792}
 793
 794static void run_one_async_start(struct btrfs_work *work)
 795{
 796	struct async_submit_bio *async;
 797	int ret;
 798
 799	async = container_of(work, struct  async_submit_bio, work);
 800	ret = async->submit_bio_start(async->inode, async->rw, async->bio,
 801				      async->mirror_num, async->bio_flags,
 802				      async->bio_offset);
 803	if (ret)
 804		async->error = ret;
 805}
 806
 
 
 
 
 
 
 
 
 807static void run_one_async_done(struct btrfs_work *work)
 808{
 809	struct btrfs_fs_info *fs_info;
 810	struct async_submit_bio *async;
 811	int limit;
 
 812
 813	async = container_of(work, struct  async_submit_bio, work);
 814	fs_info = BTRFS_I(async->inode)->root->fs_info;
 815
 816	limit = btrfs_async_submit_limit(fs_info);
 817	limit = limit * 2 / 3;
 818
 819	/*
 820	 * atomic_dec_return implies a barrier for waitqueue_active
 821	 */
 822	if (atomic_dec_return(&fs_info->nr_async_submits) < limit &&
 823	    waitqueue_active(&fs_info->async_submit_wait))
 824		wake_up(&fs_info->async_submit_wait);
 825
 826	/* If an error occurred we just want to clean up the bio and move on */
 827	if (async->error) {
 828		async->bio->bi_error = async->error;
 829		bio_endio(async->bio);
 830		return;
 831	}
 832
 833	async->submit_bio_done(async->inode, async->rw, async->bio,
 834			       async->mirror_num, async->bio_flags,
 835			       async->bio_offset);
 
 
 
 836}
 837
 838static void run_one_async_free(struct btrfs_work *work)
 839{
 840	struct async_submit_bio *async;
 841
 842	async = container_of(work, struct  async_submit_bio, work);
 843	kfree(async);
 844}
 845
 846int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
 847			int rw, struct bio *bio, int mirror_num,
 848			unsigned long bio_flags,
 849			u64 bio_offset,
 850			extent_submit_bio_hook_t *submit_bio_start,
 851			extent_submit_bio_hook_t *submit_bio_done)
 852{
 853	struct async_submit_bio *async;
 854
 855	async = kmalloc(sizeof(*async), GFP_NOFS);
 856	if (!async)
 857		return -ENOMEM;
 858
 859	async->inode = inode;
 860	async->rw = rw;
 861	async->bio = bio;
 862	async->mirror_num = mirror_num;
 863	async->submit_bio_start = submit_bio_start;
 864	async->submit_bio_done = submit_bio_done;
 865
 866	btrfs_init_work(&async->work, btrfs_worker_helper, run_one_async_start,
 867			run_one_async_done, run_one_async_free);
 868
 869	async->bio_flags = bio_flags;
 870	async->bio_offset = bio_offset;
 871
 872	async->error = 0;
 873
 874	atomic_inc(&fs_info->nr_async_submits);
 875
 876	if (rw & REQ_SYNC)
 877		btrfs_set_work_high_priority(&async->work);
 878
 879	btrfs_queue_work(fs_info->workers, &async->work);
 880
 881	while (atomic_read(&fs_info->async_submit_draining) &&
 882	      atomic_read(&fs_info->nr_async_submits)) {
 883		wait_event(fs_info->async_submit_wait,
 884			   (atomic_read(&fs_info->nr_async_submits) == 0));
 885	}
 886
 887	return 0;
 888}
 889
 890static int btree_csum_one_bio(struct bio *bio)
 891{
 892	struct bio_vec *bvec;
 893	struct btrfs_root *root;
 894	int i, ret = 0;
 
 895
 896	bio_for_each_segment_all(bvec, bio, i) {
 
 897		root = BTRFS_I(bvec->bv_page->mapping->host)->root;
 898		ret = csum_dirty_buffer(root->fs_info, bvec->bv_page);
 899		if (ret)
 900			break;
 901	}
 902
 903	return ret;
 904}
 905
 906static int __btree_submit_bio_start(struct inode *inode, int rw,
 907				    struct bio *bio, int mirror_num,
 908				    unsigned long bio_flags,
 909				    u64 bio_offset)
 910{
 911	/*
 912	 * when we're called for a write, we're already in the async
 913	 * submission context.  Just jump into btrfs_map_bio
 914	 */
 915	return btree_csum_one_bio(bio);
 916}
 917
 918static int __btree_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
 919				 int mirror_num, unsigned long bio_flags,
 920				 u64 bio_offset)
 921{
 922	int ret;
 923
 924	/*
 925	 * when we're called for a write, we're already in the async
 926	 * submission context.  Just jump into btrfs_map_bio
 927	 */
 928	ret = btrfs_map_bio(BTRFS_I(inode)->root, rw, bio, mirror_num, 1);
 929	if (ret) {
 930		bio->bi_error = ret;
 931		bio_endio(bio);
 932	}
 933	return ret;
 934}
 935
 936static int check_async_write(struct inode *inode, unsigned long bio_flags)
 937{
 938	if (bio_flags & EXTENT_BIO_TREE_LOG)
 939		return 0;
 940#ifdef CONFIG_X86
 941	if (static_cpu_has(X86_FEATURE_XMM4_2))
 942		return 0;
 943#endif
 944	return 1;
 945}
 946
 947static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
 948				 int mirror_num, unsigned long bio_flags,
 949				 u64 bio_offset)
 950{
 951	int async = check_async_write(inode, bio_flags);
 952	int ret;
 
 953
 954	if (!(rw & REQ_WRITE)) {
 955		/*
 956		 * called for a read, do the setup so that checksum validation
 957		 * can happen in the async kernel threads
 958		 */
 959		ret = btrfs_bio_wq_end_io(BTRFS_I(inode)->root->fs_info,
 960					  bio, BTRFS_WQ_ENDIO_METADATA);
 961		if (ret)
 962			goto out_w_error;
 963		ret = btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
 964				    mirror_num, 0);
 965	} else if (!async) {
 966		ret = btree_csum_one_bio(bio);
 967		if (ret)
 968			goto out_w_error;
 969		ret = btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
 970				    mirror_num, 0);
 971	} else {
 972		/*
 973		 * kthread helpers are used to submit writes so that
 974		 * checksumming can happen in parallel across all CPUs
 975		 */
 976		ret = btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
 977					  inode, rw, bio, mirror_num, 0,
 978					  bio_offset,
 979					  __btree_submit_bio_start,
 980					  __btree_submit_bio_done);
 981	}
 982
 983	if (ret)
 984		goto out_w_error;
 985	return 0;
 986
 987out_w_error:
 988	bio->bi_error = ret;
 989	bio_endio(bio);
 990	return ret;
 991}
 992
 993#ifdef CONFIG_MIGRATION
 994static int btree_migratepage(struct address_space *mapping,
 995			struct page *newpage, struct page *page,
 996			enum migrate_mode mode)
 997{
 998	/*
 999	 * we can't safely write a btree page from here,
1000	 * we haven't done the locking hook
1001	 */
1002	if (PageDirty(page))
1003		return -EAGAIN;
1004	/*
1005	 * Buffers may be managed in a filesystem specific way.
1006	 * We must have no buffers or drop them.
1007	 */
1008	if (page_has_private(page) &&
1009	    !try_to_release_page(page, GFP_KERNEL))
1010		return -EAGAIN;
1011	return migrate_page(mapping, newpage, page, mode);
1012}
1013#endif
1014
1015
1016static int btree_writepages(struct address_space *mapping,
1017			    struct writeback_control *wbc)
1018{
1019	struct btrfs_fs_info *fs_info;
1020	int ret;
1021
1022	if (wbc->sync_mode == WB_SYNC_NONE) {
1023
1024		if (wbc->for_kupdate)
1025			return 0;
1026
1027		fs_info = BTRFS_I(mapping->host)->root->fs_info;
1028		/* this is a bit racy, but that's ok */
1029		ret = percpu_counter_compare(&fs_info->dirty_metadata_bytes,
1030					     BTRFS_DIRTY_METADATA_THRESH);
 
1031		if (ret < 0)
1032			return 0;
1033	}
1034	return btree_write_cache_pages(mapping, wbc);
1035}
1036
1037static int btree_readpage(struct file *file, struct page *page)
1038{
1039	struct extent_io_tree *tree;
1040	tree = &BTRFS_I(page->mapping->host)->io_tree;
1041	return extent_read_full_page(tree, page, btree_get_extent, 0);
1042}
1043
1044static int btree_releasepage(struct page *page, gfp_t gfp_flags)
1045{
1046	if (PageWriteback(page) || PageDirty(page))
1047		return 0;
1048
1049	return try_release_extent_buffer(page);
1050}
1051
1052static void btree_invalidatepage(struct page *page, unsigned int offset,
1053				 unsigned int length)
1054{
1055	struct extent_io_tree *tree;
1056	tree = &BTRFS_I(page->mapping->host)->io_tree;
1057	extent_invalidatepage(tree, page, offset);
1058	btree_releasepage(page, GFP_NOFS);
1059	if (PagePrivate(page)) {
1060		btrfs_warn(BTRFS_I(page->mapping->host)->root->fs_info,
1061			   "page private not zero on page %llu",
1062			   (unsigned long long)page_offset(page));
1063		ClearPagePrivate(page);
1064		set_page_private(page, 0);
1065		put_page(page);
1066	}
1067}
1068
1069static int btree_set_page_dirty(struct page *page)
1070{
1071#ifdef DEBUG
1072	struct extent_buffer *eb;
1073
1074	BUG_ON(!PagePrivate(page));
1075	eb = (struct extent_buffer *)page->private;
1076	BUG_ON(!eb);
1077	BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
1078	BUG_ON(!atomic_read(&eb->refs));
1079	btrfs_assert_tree_locked(eb);
1080#endif
1081	return __set_page_dirty_nobuffers(page);
1082}
1083
1084static const struct address_space_operations btree_aops = {
1085	.readpage	= btree_readpage,
1086	.writepages	= btree_writepages,
1087	.releasepage	= btree_releasepage,
1088	.invalidatepage = btree_invalidatepage,
1089#ifdef CONFIG_MIGRATION
1090	.migratepage	= btree_migratepage,
1091#endif
1092	.set_page_dirty = btree_set_page_dirty,
1093};
1094
1095void readahead_tree_block(struct btrfs_root *root, u64 bytenr)
1096{
1097	struct extent_buffer *buf = NULL;
1098	struct inode *btree_inode = root->fs_info->btree_inode;
1099
1100	buf = btrfs_find_create_tree_block(root, bytenr);
1101	if (!buf)
1102		return;
1103	read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
1104				 buf, 0, WAIT_NONE, btree_get_extent, 0);
1105	free_extent_buffer(buf);
1106}
1107
1108int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr,
1109			 int mirror_num, struct extent_buffer **eb)
1110{
1111	struct extent_buffer *buf = NULL;
1112	struct inode *btree_inode = root->fs_info->btree_inode;
1113	struct extent_io_tree *io_tree = &BTRFS_I(btree_inode)->io_tree;
1114	int ret;
1115
1116	buf = btrfs_find_create_tree_block(root, bytenr);
1117	if (!buf)
1118		return 0;
1119
1120	set_bit(EXTENT_BUFFER_READAHEAD, &buf->bflags);
1121
1122	ret = read_extent_buffer_pages(io_tree, buf, 0, WAIT_PAGE_LOCK,
1123				       btree_get_extent, mirror_num);
1124	if (ret) {
1125		free_extent_buffer(buf);
1126		return ret;
1127	}
1128
1129	if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) {
1130		free_extent_buffer(buf);
1131		return -EIO;
1132	} else if (extent_buffer_uptodate(buf)) {
1133		*eb = buf;
1134	} else {
1135		free_extent_buffer(buf);
1136	}
1137	return 0;
1138}
1139
1140struct extent_buffer *btrfs_find_tree_block(struct btrfs_fs_info *fs_info,
1141					    u64 bytenr)
1142{
1143	return find_extent_buffer(fs_info, bytenr);
 
 
 
1144}
1145
1146struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
1147						 u64 bytenr)
1148{
1149	if (btrfs_test_is_dummy_root(root))
1150		return alloc_test_extent_buffer(root->fs_info, bytenr);
1151	return alloc_extent_buffer(root->fs_info, bytenr);
1152}
1153
1154
1155int btrfs_write_tree_block(struct extent_buffer *buf)
1156{
1157	return filemap_fdatawrite_range(buf->pages[0]->mapping, buf->start,
1158					buf->start + buf->len - 1);
1159}
1160
1161int btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
1162{
1163	return filemap_fdatawait_range(buf->pages[0]->mapping,
1164				       buf->start, buf->start + buf->len - 1);
1165}
1166
1167struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
1168				      u64 parent_transid)
1169{
1170	struct extent_buffer *buf = NULL;
1171	int ret;
1172
1173	buf = btrfs_find_create_tree_block(root, bytenr);
1174	if (!buf)
1175		return ERR_PTR(-ENOMEM);
1176
1177	ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
 
1178	if (ret) {
1179		free_extent_buffer(buf);
1180		return ERR_PTR(ret);
1181	}
1182	return buf;
1183
1184}
1185
1186void clean_tree_block(struct btrfs_trans_handle *trans,
1187		      struct btrfs_fs_info *fs_info,
1188		      struct extent_buffer *buf)
1189{
 
1190	if (btrfs_header_generation(buf) ==
1191	    fs_info->running_transaction->transid) {
1192		btrfs_assert_tree_locked(buf);
1193
1194		if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
1195			__percpu_counter_add(&fs_info->dirty_metadata_bytes,
1196					     -buf->len,
1197					     fs_info->dirty_metadata_batch);
1198			/* ugh, clear_extent_buffer_dirty needs to lock the page */
1199			btrfs_set_lock_blocking(buf);
1200			clear_extent_buffer_dirty(buf);
1201		}
1202	}
1203}
1204
1205static struct btrfs_subvolume_writers *btrfs_alloc_subvolume_writers(void)
1206{
1207	struct btrfs_subvolume_writers *writers;
1208	int ret;
1209
1210	writers = kmalloc(sizeof(*writers), GFP_NOFS);
1211	if (!writers)
1212		return ERR_PTR(-ENOMEM);
1213
1214	ret = percpu_counter_init(&writers->counter, 0, GFP_KERNEL);
1215	if (ret < 0) {
1216		kfree(writers);
1217		return ERR_PTR(ret);
1218	}
1219
1220	init_waitqueue_head(&writers->wait);
1221	return writers;
1222}
1223
1224static void
1225btrfs_free_subvolume_writers(struct btrfs_subvolume_writers *writers)
1226{
1227	percpu_counter_destroy(&writers->counter);
1228	kfree(writers);
1229}
1230
1231static void __setup_root(u32 nodesize, u32 sectorsize, u32 stripesize,
1232			 struct btrfs_root *root, struct btrfs_fs_info *fs_info,
1233			 u64 objectid)
1234{
 
1235	root->node = NULL;
1236	root->commit_root = NULL;
1237	root->sectorsize = sectorsize;
1238	root->nodesize = nodesize;
1239	root->stripesize = stripesize;
1240	root->state = 0;
1241	root->orphan_cleanup_state = 0;
1242
1243	root->objectid = objectid;
1244	root->last_trans = 0;
1245	root->highest_objectid = 0;
1246	root->nr_delalloc_inodes = 0;
1247	root->nr_ordered_extents = 0;
1248	root->name = NULL;
1249	root->inode_tree = RB_ROOT;
1250	INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
1251	root->block_rsv = NULL;
1252	root->orphan_block_rsv = NULL;
1253
1254	INIT_LIST_HEAD(&root->dirty_list);
1255	INIT_LIST_HEAD(&root->root_list);
1256	INIT_LIST_HEAD(&root->delalloc_inodes);
1257	INIT_LIST_HEAD(&root->delalloc_root);
1258	INIT_LIST_HEAD(&root->ordered_extents);
1259	INIT_LIST_HEAD(&root->ordered_root);
 
1260	INIT_LIST_HEAD(&root->logged_list[0]);
1261	INIT_LIST_HEAD(&root->logged_list[1]);
1262	spin_lock_init(&root->orphan_lock);
1263	spin_lock_init(&root->inode_lock);
1264	spin_lock_init(&root->delalloc_lock);
1265	spin_lock_init(&root->ordered_extent_lock);
1266	spin_lock_init(&root->accounting_lock);
1267	spin_lock_init(&root->log_extents_lock[0]);
1268	spin_lock_init(&root->log_extents_lock[1]);
 
1269	mutex_init(&root->objectid_mutex);
1270	mutex_init(&root->log_mutex);
1271	mutex_init(&root->ordered_extent_mutex);
1272	mutex_init(&root->delalloc_mutex);
1273	init_waitqueue_head(&root->log_writer_wait);
1274	init_waitqueue_head(&root->log_commit_wait[0]);
1275	init_waitqueue_head(&root->log_commit_wait[1]);
1276	INIT_LIST_HEAD(&root->log_ctxs[0]);
1277	INIT_LIST_HEAD(&root->log_ctxs[1]);
1278	atomic_set(&root->log_commit[0], 0);
1279	atomic_set(&root->log_commit[1], 0);
1280	atomic_set(&root->log_writers, 0);
1281	atomic_set(&root->log_batch, 0);
1282	atomic_set(&root->orphan_inodes, 0);
1283	atomic_set(&root->refs, 1);
1284	atomic_set(&root->will_be_snapshoted, 0);
1285	atomic_set(&root->qgroup_meta_rsv, 0);
1286	root->log_transid = 0;
1287	root->log_transid_committed = -1;
1288	root->last_log_commit = 0;
1289	if (fs_info)
1290		extent_io_tree_init(&root->dirty_log_pages,
1291				     fs_info->btree_inode->i_mapping);
1292
1293	memset(&root->root_key, 0, sizeof(root->root_key));
1294	memset(&root->root_item, 0, sizeof(root->root_item));
1295	memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
1296	if (fs_info)
1297		root->defrag_trans_start = fs_info->generation;
1298	else
1299		root->defrag_trans_start = 0;
1300	root->root_key.objectid = objectid;
1301	root->anon_dev = 0;
1302
1303	spin_lock_init(&root->root_item_lock);
 
1304}
1305
1306static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info,
1307		gfp_t flags)
1308{
1309	struct btrfs_root *root = kzalloc(sizeof(*root), flags);
1310	if (root)
1311		root->fs_info = fs_info;
1312	return root;
1313}
1314
1315#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
1316/* Should only be used by the testing infrastructure */
1317struct btrfs_root *btrfs_alloc_dummy_root(void)
1318{
1319	struct btrfs_root *root;
1320
1321	root = btrfs_alloc_root(NULL, GFP_KERNEL);
 
 
 
1322	if (!root)
1323		return ERR_PTR(-ENOMEM);
1324	__setup_root(4096, 4096, 4096, root, NULL, 1);
1325	set_bit(BTRFS_ROOT_DUMMY_ROOT, &root->state);
 
1326	root->alloc_bytenr = 0;
1327
1328	return root;
1329}
1330#endif
1331
1332struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
1333				     struct btrfs_fs_info *fs_info,
1334				     u64 objectid)
1335{
 
1336	struct extent_buffer *leaf;
1337	struct btrfs_root *tree_root = fs_info->tree_root;
1338	struct btrfs_root *root;
1339	struct btrfs_key key;
 
1340	int ret = 0;
1341	uuid_le uuid;
1342
 
 
 
 
 
1343	root = btrfs_alloc_root(fs_info, GFP_KERNEL);
 
1344	if (!root)
1345		return ERR_PTR(-ENOMEM);
1346
1347	__setup_root(tree_root->nodesize, tree_root->sectorsize,
1348		tree_root->stripesize, root, fs_info, objectid);
1349	root->root_key.objectid = objectid;
1350	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1351	root->root_key.offset = 0;
1352
1353	leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
1354	if (IS_ERR(leaf)) {
1355		ret = PTR_ERR(leaf);
1356		leaf = NULL;
1357		goto fail;
1358	}
1359
1360	memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
1361	btrfs_set_header_bytenr(leaf, leaf->start);
1362	btrfs_set_header_generation(leaf, trans->transid);
1363	btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
1364	btrfs_set_header_owner(leaf, objectid);
1365	root->node = leaf;
1366
1367	write_extent_buffer(leaf, fs_info->fsid, btrfs_header_fsid(),
1368			    BTRFS_FSID_SIZE);
1369	write_extent_buffer(leaf, fs_info->chunk_tree_uuid,
1370			    btrfs_header_chunk_tree_uuid(leaf),
1371			    BTRFS_UUID_SIZE);
1372	btrfs_mark_buffer_dirty(leaf);
1373
1374	root->commit_root = btrfs_root_node(root);
1375	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
1376
1377	root->root_item.flags = 0;
1378	root->root_item.byte_limit = 0;
1379	btrfs_set_root_bytenr(&root->root_item, leaf->start);
1380	btrfs_set_root_generation(&root->root_item, trans->transid);
1381	btrfs_set_root_level(&root->root_item, 0);
1382	btrfs_set_root_refs(&root->root_item, 1);
1383	btrfs_set_root_used(&root->root_item, leaf->len);
1384	btrfs_set_root_last_snapshot(&root->root_item, 0);
1385	btrfs_set_root_dirid(&root->root_item, 0);
1386	uuid_le_gen(&uuid);
 
1387	memcpy(root->root_item.uuid, uuid.b, BTRFS_UUID_SIZE);
1388	root->root_item.drop_level = 0;
1389
1390	key.objectid = objectid;
1391	key.type = BTRFS_ROOT_ITEM_KEY;
1392	key.offset = 0;
1393	ret = btrfs_insert_root(trans, tree_root, &key, &root->root_item);
1394	if (ret)
1395		goto fail;
1396
1397	btrfs_tree_unlock(leaf);
1398
1399	return root;
1400
1401fail:
1402	if (leaf) {
1403		btrfs_tree_unlock(leaf);
1404		free_extent_buffer(root->commit_root);
1405		free_extent_buffer(leaf);
1406	}
1407	kfree(root);
1408
1409	return ERR_PTR(ret);
1410}
1411
1412static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
1413					 struct btrfs_fs_info *fs_info)
1414{
1415	struct btrfs_root *root;
1416	struct btrfs_root *tree_root = fs_info->tree_root;
1417	struct extent_buffer *leaf;
1418
1419	root = btrfs_alloc_root(fs_info, GFP_NOFS);
1420	if (!root)
1421		return ERR_PTR(-ENOMEM);
1422
1423	__setup_root(tree_root->nodesize, tree_root->sectorsize,
1424		     tree_root->stripesize, root, fs_info,
1425		     BTRFS_TREE_LOG_OBJECTID);
1426
1427	root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1428	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1429	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
1430
1431	/*
1432	 * DON'T set REF_COWS for log trees
1433	 *
1434	 * log trees do not get reference counted because they go away
1435	 * before a real commit is actually done.  They do store pointers
1436	 * to file data extents, and those reference counts still get
1437	 * updated (along with back refs to the log tree).
1438	 */
1439
1440	leaf = btrfs_alloc_tree_block(trans, root, 0, BTRFS_TREE_LOG_OBJECTID,
1441			NULL, 0, 0, 0);
1442	if (IS_ERR(leaf)) {
1443		kfree(root);
1444		return ERR_CAST(leaf);
1445	}
1446
1447	memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
1448	btrfs_set_header_bytenr(leaf, leaf->start);
1449	btrfs_set_header_generation(leaf, trans->transid);
1450	btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
1451	btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
1452	root->node = leaf;
1453
1454	write_extent_buffer(root->node, root->fs_info->fsid,
1455			    btrfs_header_fsid(), BTRFS_FSID_SIZE);
1456	btrfs_mark_buffer_dirty(root->node);
1457	btrfs_tree_unlock(root->node);
1458	return root;
1459}
1460
1461int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1462			     struct btrfs_fs_info *fs_info)
1463{
1464	struct btrfs_root *log_root;
1465
1466	log_root = alloc_log_tree(trans, fs_info);
1467	if (IS_ERR(log_root))
1468		return PTR_ERR(log_root);
1469	WARN_ON(fs_info->log_root_tree);
1470	fs_info->log_root_tree = log_root;
1471	return 0;
1472}
1473
1474int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1475		       struct btrfs_root *root)
1476{
 
1477	struct btrfs_root *log_root;
1478	struct btrfs_inode_item *inode_item;
1479
1480	log_root = alloc_log_tree(trans, root->fs_info);
1481	if (IS_ERR(log_root))
1482		return PTR_ERR(log_root);
1483
1484	log_root->last_trans = trans->transid;
1485	log_root->root_key.offset = root->root_key.objectid;
1486
1487	inode_item = &log_root->root_item.inode;
1488	btrfs_set_stack_inode_generation(inode_item, 1);
1489	btrfs_set_stack_inode_size(inode_item, 3);
1490	btrfs_set_stack_inode_nlink(inode_item, 1);
1491	btrfs_set_stack_inode_nbytes(inode_item, root->nodesize);
 
1492	btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
1493
1494	btrfs_set_root_node(&log_root->root_item, log_root->node);
1495
1496	WARN_ON(root->log_root);
1497	root->log_root = log_root;
1498	root->log_transid = 0;
1499	root->log_transid_committed = -1;
1500	root->last_log_commit = 0;
1501	return 0;
1502}
1503
1504static struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
1505					       struct btrfs_key *key)
1506{
1507	struct btrfs_root *root;
1508	struct btrfs_fs_info *fs_info = tree_root->fs_info;
1509	struct btrfs_path *path;
1510	u64 generation;
1511	int ret;
 
1512
1513	path = btrfs_alloc_path();
1514	if (!path)
1515		return ERR_PTR(-ENOMEM);
1516
1517	root = btrfs_alloc_root(fs_info, GFP_NOFS);
1518	if (!root) {
1519		ret = -ENOMEM;
1520		goto alloc_fail;
1521	}
1522
1523	__setup_root(tree_root->nodesize, tree_root->sectorsize,
1524		tree_root->stripesize, root, fs_info, key->objectid);
1525
1526	ret = btrfs_find_root(tree_root, key, path,
1527			      &root->root_item, &root->root_key);
1528	if (ret) {
1529		if (ret > 0)
1530			ret = -ENOENT;
1531		goto find_fail;
1532	}
1533
1534	generation = btrfs_root_generation(&root->root_item);
1535	root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
1536				     generation);
 
 
1537	if (IS_ERR(root->node)) {
1538		ret = PTR_ERR(root->node);
1539		goto find_fail;
1540	} else if (!btrfs_buffer_uptodate(root->node, generation, 0)) {
1541		ret = -EIO;
1542		free_extent_buffer(root->node);
1543		goto find_fail;
1544	}
1545	root->commit_root = btrfs_root_node(root);
1546out:
1547	btrfs_free_path(path);
1548	return root;
1549
1550find_fail:
1551	kfree(root);
1552alloc_fail:
1553	root = ERR_PTR(ret);
1554	goto out;
1555}
1556
1557struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root,
1558				      struct btrfs_key *location)
1559{
1560	struct btrfs_root *root;
1561
1562	root = btrfs_read_tree_root(tree_root, location);
1563	if (IS_ERR(root))
1564		return root;
1565
1566	if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
1567		set_bit(BTRFS_ROOT_REF_COWS, &root->state);
1568		btrfs_check_and_init_root_item(&root->root_item);
1569	}
1570
1571	return root;
1572}
1573
1574int btrfs_init_fs_root(struct btrfs_root *root)
1575{
1576	int ret;
1577	struct btrfs_subvolume_writers *writers;
1578
1579	root->free_ino_ctl = kzalloc(sizeof(*root->free_ino_ctl), GFP_NOFS);
1580	root->free_ino_pinned = kzalloc(sizeof(*root->free_ino_pinned),
1581					GFP_NOFS);
1582	if (!root->free_ino_pinned || !root->free_ino_ctl) {
1583		ret = -ENOMEM;
1584		goto fail;
1585	}
1586
1587	writers = btrfs_alloc_subvolume_writers();
1588	if (IS_ERR(writers)) {
1589		ret = PTR_ERR(writers);
1590		goto fail;
1591	}
1592	root->subv_writers = writers;
1593
1594	btrfs_init_free_ino_ctl(root);
1595	spin_lock_init(&root->ino_cache_lock);
1596	init_waitqueue_head(&root->ino_cache_wait);
1597
1598	ret = get_anon_bdev(&root->anon_dev);
1599	if (ret)
1600		goto free_writers;
1601
1602	mutex_lock(&root->objectid_mutex);
1603	ret = btrfs_find_highest_objectid(root,
1604					&root->highest_objectid);
1605	if (ret) {
1606		mutex_unlock(&root->objectid_mutex);
1607		goto free_root_dev;
1608	}
1609
1610	ASSERT(root->highest_objectid <= BTRFS_LAST_FREE_OBJECTID);
1611
1612	mutex_unlock(&root->objectid_mutex);
1613
1614	return 0;
1615
1616free_root_dev:
1617	free_anon_bdev(root->anon_dev);
1618free_writers:
1619	btrfs_free_subvolume_writers(root->subv_writers);
1620fail:
1621	kfree(root->free_ino_ctl);
1622	kfree(root->free_ino_pinned);
1623	return ret;
1624}
1625
1626static struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
1627					       u64 root_id)
1628{
1629	struct btrfs_root *root;
1630
1631	spin_lock(&fs_info->fs_roots_radix_lock);
1632	root = radix_tree_lookup(&fs_info->fs_roots_radix,
1633				 (unsigned long)root_id);
1634	spin_unlock(&fs_info->fs_roots_radix_lock);
1635	return root;
1636}
1637
1638int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
1639			 struct btrfs_root *root)
1640{
1641	int ret;
1642
1643	ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
1644	if (ret)
1645		return ret;
1646
1647	spin_lock(&fs_info->fs_roots_radix_lock);
1648	ret = radix_tree_insert(&fs_info->fs_roots_radix,
1649				(unsigned long)root->root_key.objectid,
1650				root);
1651	if (ret == 0)
1652		set_bit(BTRFS_ROOT_IN_RADIX, &root->state);
1653	spin_unlock(&fs_info->fs_roots_radix_lock);
1654	radix_tree_preload_end();
1655
1656	return ret;
1657}
1658
1659struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
1660				     struct btrfs_key *location,
1661				     bool check_ref)
1662{
1663	struct btrfs_root *root;
1664	struct btrfs_path *path;
1665	struct btrfs_key key;
1666	int ret;
1667
1668	if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1669		return fs_info->tree_root;
1670	if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
1671		return fs_info->extent_root;
1672	if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
1673		return fs_info->chunk_root;
1674	if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
1675		return fs_info->dev_root;
1676	if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
1677		return fs_info->csum_root;
1678	if (location->objectid == BTRFS_QUOTA_TREE_OBJECTID)
1679		return fs_info->quota_root ? fs_info->quota_root :
1680					     ERR_PTR(-ENOENT);
1681	if (location->objectid == BTRFS_UUID_TREE_OBJECTID)
1682		return fs_info->uuid_root ? fs_info->uuid_root :
1683					    ERR_PTR(-ENOENT);
1684	if (location->objectid == BTRFS_FREE_SPACE_TREE_OBJECTID)
1685		return fs_info->free_space_root ? fs_info->free_space_root :
1686						  ERR_PTR(-ENOENT);
1687again:
1688	root = btrfs_lookup_fs_root(fs_info, location->objectid);
1689	if (root) {
1690		if (check_ref && btrfs_root_refs(&root->root_item) == 0)
1691			return ERR_PTR(-ENOENT);
1692		return root;
1693	}
1694
1695	root = btrfs_read_fs_root(fs_info->tree_root, location);
1696	if (IS_ERR(root))
1697		return root;
1698
1699	if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1700		ret = -ENOENT;
1701		goto fail;
1702	}
1703
1704	ret = btrfs_init_fs_root(root);
1705	if (ret)
1706		goto fail;
1707
1708	path = btrfs_alloc_path();
1709	if (!path) {
1710		ret = -ENOMEM;
1711		goto fail;
1712	}
1713	key.objectid = BTRFS_ORPHAN_OBJECTID;
1714	key.type = BTRFS_ORPHAN_ITEM_KEY;
1715	key.offset = location->objectid;
1716
1717	ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
1718	btrfs_free_path(path);
1719	if (ret < 0)
1720		goto fail;
1721	if (ret == 0)
1722		set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state);
1723
1724	ret = btrfs_insert_fs_root(fs_info, root);
1725	if (ret) {
1726		if (ret == -EEXIST) {
1727			free_fs_root(root);
1728			goto again;
1729		}
1730		goto fail;
1731	}
1732	return root;
1733fail:
1734	free_fs_root(root);
1735	return ERR_PTR(ret);
1736}
1737
1738static int btrfs_congested_fn(void *congested_data, int bdi_bits)
1739{
1740	struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
1741	int ret = 0;
1742	struct btrfs_device *device;
1743	struct backing_dev_info *bdi;
1744
1745	rcu_read_lock();
1746	list_for_each_entry_rcu(device, &info->fs_devices->devices, dev_list) {
1747		if (!device->bdev)
1748			continue;
1749		bdi = blk_get_backing_dev_info(device->bdev);
1750		if (bdi_congested(bdi, bdi_bits)) {
1751			ret = 1;
1752			break;
1753		}
1754	}
1755	rcu_read_unlock();
1756	return ret;
1757}
1758
1759static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
1760{
1761	int err;
1762
1763	err = bdi_setup_and_register(bdi, "btrfs");
1764	if (err)
1765		return err;
1766
1767	bdi->ra_pages = VM_MAX_READAHEAD * 1024 / PAGE_SIZE;
1768	bdi->congested_fn	= btrfs_congested_fn;
1769	bdi->congested_data	= info;
1770	bdi->capabilities |= BDI_CAP_CGROUP_WRITEBACK;
1771	return 0;
1772}
1773
1774/*
1775 * called by the kthread helper functions to finally call the bio end_io
1776 * functions.  This is where read checksum verification actually happens
1777 */
1778static void end_workqueue_fn(struct btrfs_work *work)
1779{
1780	struct bio *bio;
1781	struct btrfs_end_io_wq *end_io_wq;
1782
1783	end_io_wq = container_of(work, struct btrfs_end_io_wq, work);
1784	bio = end_io_wq->bio;
1785
1786	bio->bi_error = end_io_wq->error;
1787	bio->bi_private = end_io_wq->private;
1788	bio->bi_end_io = end_io_wq->end_io;
1789	kmem_cache_free(btrfs_end_io_wq_cache, end_io_wq);
1790	bio_endio(bio);
1791}
1792
1793static int cleaner_kthread(void *arg)
1794{
1795	struct btrfs_root *root = arg;
 
1796	int again;
1797	struct btrfs_trans_handle *trans;
1798
1799	do {
1800		again = 0;
1801
 
 
1802		/* Make the cleaner go to sleep early. */
1803		if (btrfs_need_cleaner_sleep(root))
 
 
 
 
 
 
 
1804			goto sleep;
1805
1806		if (!mutex_trylock(&root->fs_info->cleaner_mutex))
1807			goto sleep;
1808
1809		/*
1810		 * Avoid the problem that we change the status of the fs
1811		 * during the above check and trylock.
1812		 */
1813		if (btrfs_need_cleaner_sleep(root)) {
1814			mutex_unlock(&root->fs_info->cleaner_mutex);
1815			goto sleep;
1816		}
1817
1818		mutex_lock(&root->fs_info->cleaner_delayed_iput_mutex);
1819		btrfs_run_delayed_iputs(root);
1820		mutex_unlock(&root->fs_info->cleaner_delayed_iput_mutex);
1821
1822		again = btrfs_clean_one_deleted_snapshot(root);
1823		mutex_unlock(&root->fs_info->cleaner_mutex);
1824
1825		/*
1826		 * The defragger has dealt with the R/O remount and umount,
1827		 * needn't do anything special here.
1828		 */
1829		btrfs_run_defrag_inodes(root->fs_info);
1830
1831		/*
1832		 * Acquires fs_info->delete_unused_bgs_mutex to avoid racing
1833		 * with relocation (btrfs_relocate_chunk) and relocation
1834		 * acquires fs_info->cleaner_mutex (btrfs_relocate_block_group)
1835		 * after acquiring fs_info->delete_unused_bgs_mutex. So we
1836		 * can't hold, nor need to, fs_info->cleaner_mutex when deleting
1837		 * unused block groups.
1838		 */
1839		btrfs_delete_unused_bgs(root->fs_info);
1840sleep:
 
 
 
 
 
1841		if (!again) {
1842			set_current_state(TASK_INTERRUPTIBLE);
1843			if (!kthread_should_stop())
1844				schedule();
1845			__set_current_state(TASK_RUNNING);
1846		}
1847	} while (!kthread_should_stop());
1848
1849	/*
1850	 * Transaction kthread is stopped before us and wakes us up.
1851	 * However we might have started a new transaction and COWed some
1852	 * tree blocks when deleting unused block groups for example. So
1853	 * make sure we commit the transaction we started to have a clean
1854	 * shutdown when evicting the btree inode - if it has dirty pages
1855	 * when we do the final iput() on it, eviction will trigger a
1856	 * writeback for it which will fail with null pointer dereferences
1857	 * since work queues and other resources were already released and
1858	 * destroyed by the time the iput/eviction/writeback is made.
1859	 */
1860	trans = btrfs_attach_transaction(root);
1861	if (IS_ERR(trans)) {
1862		if (PTR_ERR(trans) != -ENOENT)
1863			btrfs_err(root->fs_info,
1864				  "cleaner transaction attach returned %ld",
1865				  PTR_ERR(trans));
1866	} else {
1867		int ret;
1868
1869		ret = btrfs_commit_transaction(trans, root);
1870		if (ret)
1871			btrfs_err(root->fs_info,
1872				  "cleaner open transaction commit returned %d",
1873				  ret);
1874	}
1875
1876	return 0;
1877}
1878
1879static int transaction_kthread(void *arg)
1880{
1881	struct btrfs_root *root = arg;
 
1882	struct btrfs_trans_handle *trans;
1883	struct btrfs_transaction *cur;
1884	u64 transid;
1885	unsigned long now;
1886	unsigned long delay;
1887	bool cannot_commit;
1888
1889	do {
1890		cannot_commit = false;
1891		delay = HZ * root->fs_info->commit_interval;
1892		mutex_lock(&root->fs_info->transaction_kthread_mutex);
1893
1894		spin_lock(&root->fs_info->trans_lock);
1895		cur = root->fs_info->running_transaction;
1896		if (!cur) {
1897			spin_unlock(&root->fs_info->trans_lock);
1898			goto sleep;
1899		}
1900
1901		now = get_seconds();
1902		if (cur->state < TRANS_STATE_BLOCKED &&
 
1903		    (now < cur->start_time ||
1904		     now - cur->start_time < root->fs_info->commit_interval)) {
1905			spin_unlock(&root->fs_info->trans_lock);
1906			delay = HZ * 5;
1907			goto sleep;
1908		}
1909		transid = cur->transid;
1910		spin_unlock(&root->fs_info->trans_lock);
1911
1912		/* If the file system is aborted, this will always fail. */
1913		trans = btrfs_attach_transaction(root);
1914		if (IS_ERR(trans)) {
1915			if (PTR_ERR(trans) != -ENOENT)
1916				cannot_commit = true;
1917			goto sleep;
1918		}
1919		if (transid == trans->transid) {
1920			btrfs_commit_transaction(trans, root);
1921		} else {
1922			btrfs_end_transaction(trans, root);
1923		}
1924sleep:
1925		wake_up_process(root->fs_info->cleaner_kthread);
1926		mutex_unlock(&root->fs_info->transaction_kthread_mutex);
1927
1928		if (unlikely(test_bit(BTRFS_FS_STATE_ERROR,
1929				      &root->fs_info->fs_state)))
1930			btrfs_cleanup_transaction(root);
1931		set_current_state(TASK_INTERRUPTIBLE);
1932		if (!kthread_should_stop() &&
1933				(!btrfs_transaction_blocked(root->fs_info) ||
1934				 cannot_commit))
1935			schedule_timeout(delay);
1936		__set_current_state(TASK_RUNNING);
1937	} while (!kthread_should_stop());
1938	return 0;
1939}
1940
1941/*
1942 * this will find the highest generation in the array of
1943 * root backups.  The index of the highest array is returned,
1944 * or -1 if we can't find anything.
1945 *
1946 * We check to make sure the array is valid by comparing the
1947 * generation of the latest  root in the array with the generation
1948 * in the super block.  If they don't match we pitch it.
1949 */
1950static int find_newest_super_backup(struct btrfs_fs_info *info, u64 newest_gen)
1951{
1952	u64 cur;
1953	int newest_index = -1;
1954	struct btrfs_root_backup *root_backup;
1955	int i;
1956
1957	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
1958		root_backup = info->super_copy->super_roots + i;
1959		cur = btrfs_backup_tree_root_gen(root_backup);
1960		if (cur == newest_gen)
1961			newest_index = i;
1962	}
1963
1964	/* check to see if we actually wrapped around */
1965	if (newest_index == BTRFS_NUM_BACKUP_ROOTS - 1) {
1966		root_backup = info->super_copy->super_roots;
1967		cur = btrfs_backup_tree_root_gen(root_backup);
1968		if (cur == newest_gen)
1969			newest_index = 0;
1970	}
1971	return newest_index;
1972}
1973
1974
1975/*
1976 * find the oldest backup so we know where to store new entries
1977 * in the backup array.  This will set the backup_root_index
1978 * field in the fs_info struct
1979 */
1980static void find_oldest_super_backup(struct btrfs_fs_info *info,
1981				     u64 newest_gen)
1982{
1983	int newest_index = -1;
1984
1985	newest_index = find_newest_super_backup(info, newest_gen);
1986	/* if there was garbage in there, just move along */
1987	if (newest_index == -1) {
1988		info->backup_root_index = 0;
1989	} else {
1990		info->backup_root_index = (newest_index + 1) % BTRFS_NUM_BACKUP_ROOTS;
1991	}
1992}
1993
1994/*
1995 * copy all the root pointers into the super backup array.
1996 * this will bump the backup pointer by one when it is
1997 * done
1998 */
1999static void backup_super_roots(struct btrfs_fs_info *info)
2000{
2001	int next_backup;
2002	struct btrfs_root_backup *root_backup;
2003	int last_backup;
2004
2005	next_backup = info->backup_root_index;
2006	last_backup = (next_backup + BTRFS_NUM_BACKUP_ROOTS - 1) %
2007		BTRFS_NUM_BACKUP_ROOTS;
2008
2009	/*
2010	 * just overwrite the last backup if we're at the same generation
2011	 * this happens only at umount
2012	 */
2013	root_backup = info->super_for_commit->super_roots + last_backup;
2014	if (btrfs_backup_tree_root_gen(root_backup) ==
2015	    btrfs_header_generation(info->tree_root->node))
2016		next_backup = last_backup;
2017
2018	root_backup = info->super_for_commit->super_roots + next_backup;
2019
2020	/*
2021	 * make sure all of our padding and empty slots get zero filled
2022	 * regardless of which ones we use today
2023	 */
2024	memset(root_backup, 0, sizeof(*root_backup));
2025
2026	info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
2027
2028	btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
2029	btrfs_set_backup_tree_root_gen(root_backup,
2030			       btrfs_header_generation(info->tree_root->node));
2031
2032	btrfs_set_backup_tree_root_level(root_backup,
2033			       btrfs_header_level(info->tree_root->node));
2034
2035	btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
2036	btrfs_set_backup_chunk_root_gen(root_backup,
2037			       btrfs_header_generation(info->chunk_root->node));
2038	btrfs_set_backup_chunk_root_level(root_backup,
2039			       btrfs_header_level(info->chunk_root->node));
2040
2041	btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start);
2042	btrfs_set_backup_extent_root_gen(root_backup,
2043			       btrfs_header_generation(info->extent_root->node));
2044	btrfs_set_backup_extent_root_level(root_backup,
2045			       btrfs_header_level(info->extent_root->node));
2046
2047	/*
2048	 * we might commit during log recovery, which happens before we set
2049	 * the fs_root.  Make sure it is valid before we fill it in.
2050	 */
2051	if (info->fs_root && info->fs_root->node) {
2052		btrfs_set_backup_fs_root(root_backup,
2053					 info->fs_root->node->start);
2054		btrfs_set_backup_fs_root_gen(root_backup,
2055			       btrfs_header_generation(info->fs_root->node));
2056		btrfs_set_backup_fs_root_level(root_backup,
2057			       btrfs_header_level(info->fs_root->node));
2058	}
2059
2060	btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
2061	btrfs_set_backup_dev_root_gen(root_backup,
2062			       btrfs_header_generation(info->dev_root->node));
2063	btrfs_set_backup_dev_root_level(root_backup,
2064				       btrfs_header_level(info->dev_root->node));
2065
2066	btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start);
2067	btrfs_set_backup_csum_root_gen(root_backup,
2068			       btrfs_header_generation(info->csum_root->node));
2069	btrfs_set_backup_csum_root_level(root_backup,
2070			       btrfs_header_level(info->csum_root->node));
2071
2072	btrfs_set_backup_total_bytes(root_backup,
2073			     btrfs_super_total_bytes(info->super_copy));
2074	btrfs_set_backup_bytes_used(root_backup,
2075			     btrfs_super_bytes_used(info->super_copy));
2076	btrfs_set_backup_num_devices(root_backup,
2077			     btrfs_super_num_devices(info->super_copy));
2078
2079	/*
2080	 * if we don't copy this out to the super_copy, it won't get remembered
2081	 * for the next commit
2082	 */
2083	memcpy(&info->super_copy->super_roots,
2084	       &info->super_for_commit->super_roots,
2085	       sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
2086}
2087
2088/*
2089 * this copies info out of the root backup array and back into
2090 * the in-memory super block.  It is meant to help iterate through
2091 * the array, so you send it the number of backups you've already
2092 * tried and the last backup index you used.
2093 *
2094 * this returns -1 when it has tried all the backups
2095 */
2096static noinline int next_root_backup(struct btrfs_fs_info *info,
2097				     struct btrfs_super_block *super,
2098				     int *num_backups_tried, int *backup_index)
2099{
2100	struct btrfs_root_backup *root_backup;
2101	int newest = *backup_index;
2102
2103	if (*num_backups_tried == 0) {
2104		u64 gen = btrfs_super_generation(super);
2105
2106		newest = find_newest_super_backup(info, gen);
2107		if (newest == -1)
2108			return -1;
2109
2110		*backup_index = newest;
2111		*num_backups_tried = 1;
2112	} else if (*num_backups_tried == BTRFS_NUM_BACKUP_ROOTS) {
2113		/* we've tried all the backups, all done */
2114		return -1;
2115	} else {
2116		/* jump to the next oldest backup */
2117		newest = (*backup_index + BTRFS_NUM_BACKUP_ROOTS - 1) %
2118			BTRFS_NUM_BACKUP_ROOTS;
2119		*backup_index = newest;
2120		*num_backups_tried += 1;
2121	}
2122	root_backup = super->super_roots + newest;
2123
2124	btrfs_set_super_generation(super,
2125				   btrfs_backup_tree_root_gen(root_backup));
2126	btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
2127	btrfs_set_super_root_level(super,
2128				   btrfs_backup_tree_root_level(root_backup));
2129	btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
2130
2131	/*
2132	 * fixme: the total bytes and num_devices need to match or we should
2133	 * need a fsck
2134	 */
2135	btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
2136	btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
2137	return 0;
2138}
2139
2140/* helper to cleanup workers */
2141static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
2142{
2143	btrfs_destroy_workqueue(fs_info->fixup_workers);
2144	btrfs_destroy_workqueue(fs_info->delalloc_workers);
2145	btrfs_destroy_workqueue(fs_info->workers);
2146	btrfs_destroy_workqueue(fs_info->endio_workers);
2147	btrfs_destroy_workqueue(fs_info->endio_meta_workers);
2148	btrfs_destroy_workqueue(fs_info->endio_raid56_workers);
2149	btrfs_destroy_workqueue(fs_info->endio_repair_workers);
2150	btrfs_destroy_workqueue(fs_info->rmw_workers);
2151	btrfs_destroy_workqueue(fs_info->endio_meta_write_workers);
2152	btrfs_destroy_workqueue(fs_info->endio_write_workers);
2153	btrfs_destroy_workqueue(fs_info->endio_freespace_worker);
2154	btrfs_destroy_workqueue(fs_info->submit_workers);
2155	btrfs_destroy_workqueue(fs_info->delayed_workers);
2156	btrfs_destroy_workqueue(fs_info->caching_workers);
2157	btrfs_destroy_workqueue(fs_info->readahead_workers);
2158	btrfs_destroy_workqueue(fs_info->flush_workers);
2159	btrfs_destroy_workqueue(fs_info->qgroup_rescan_workers);
2160	btrfs_destroy_workqueue(fs_info->extent_workers);
 
 
 
 
 
 
2161}
2162
2163static void free_root_extent_buffers(struct btrfs_root *root)
2164{
2165	if (root) {
2166		free_extent_buffer(root->node);
2167		free_extent_buffer(root->commit_root);
2168		root->node = NULL;
2169		root->commit_root = NULL;
2170	}
2171}
2172
2173/* helper to cleanup tree roots */
2174static void free_root_pointers(struct btrfs_fs_info *info, int chunk_root)
2175{
2176	free_root_extent_buffers(info->tree_root);
2177
2178	free_root_extent_buffers(info->dev_root);
2179	free_root_extent_buffers(info->extent_root);
2180	free_root_extent_buffers(info->csum_root);
2181	free_root_extent_buffers(info->quota_root);
2182	free_root_extent_buffers(info->uuid_root);
2183	if (chunk_root)
2184		free_root_extent_buffers(info->chunk_root);
2185	free_root_extent_buffers(info->free_space_root);
2186}
2187
2188void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info)
2189{
2190	int ret;
2191	struct btrfs_root *gang[8];
2192	int i;
2193
2194	while (!list_empty(&fs_info->dead_roots)) {
2195		gang[0] = list_entry(fs_info->dead_roots.next,
2196				     struct btrfs_root, root_list);
2197		list_del(&gang[0]->root_list);
2198
2199		if (test_bit(BTRFS_ROOT_IN_RADIX, &gang[0]->state)) {
2200			btrfs_drop_and_free_fs_root(fs_info, gang[0]);
2201		} else {
2202			free_extent_buffer(gang[0]->node);
2203			free_extent_buffer(gang[0]->commit_root);
2204			btrfs_put_fs_root(gang[0]);
2205		}
2206	}
2207
2208	while (1) {
2209		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2210					     (void **)gang, 0,
2211					     ARRAY_SIZE(gang));
2212		if (!ret)
2213			break;
2214		for (i = 0; i < ret; i++)
2215			btrfs_drop_and_free_fs_root(fs_info, gang[i]);
2216	}
2217
2218	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
2219		btrfs_free_log_root_tree(NULL, fs_info);
2220		btrfs_destroy_pinned_extent(fs_info->tree_root,
2221					    fs_info->pinned_extents);
2222	}
2223}
2224
2225static void btrfs_init_scrub(struct btrfs_fs_info *fs_info)
2226{
2227	mutex_init(&fs_info->scrub_lock);
2228	atomic_set(&fs_info->scrubs_running, 0);
2229	atomic_set(&fs_info->scrub_pause_req, 0);
2230	atomic_set(&fs_info->scrubs_paused, 0);
2231	atomic_set(&fs_info->scrub_cancel_req, 0);
2232	init_waitqueue_head(&fs_info->scrub_pause_wait);
2233	fs_info->scrub_workers_refcnt = 0;
2234}
2235
2236static void btrfs_init_balance(struct btrfs_fs_info *fs_info)
2237{
2238	spin_lock_init(&fs_info->balance_lock);
2239	mutex_init(&fs_info->balance_mutex);
2240	atomic_set(&fs_info->balance_running, 0);
2241	atomic_set(&fs_info->balance_pause_req, 0);
2242	atomic_set(&fs_info->balance_cancel_req, 0);
2243	fs_info->balance_ctl = NULL;
2244	init_waitqueue_head(&fs_info->balance_wait_q);
2245}
2246
2247static void btrfs_init_btree_inode(struct btrfs_fs_info *fs_info,
2248				   struct btrfs_root *tree_root)
2249{
2250	fs_info->btree_inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
2251	set_nlink(fs_info->btree_inode, 1);
 
 
2252	/*
2253	 * we set the i_size on the btree inode to the max possible int.
2254	 * the real end of the address space is determined by all of
2255	 * the devices in the system
2256	 */
2257	fs_info->btree_inode->i_size = OFFSET_MAX;
2258	fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
2259
2260	RB_CLEAR_NODE(&BTRFS_I(fs_info->btree_inode)->rb_node);
2261	extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree,
2262			     fs_info->btree_inode->i_mapping);
2263	BTRFS_I(fs_info->btree_inode)->io_tree.track_uptodate = 0;
2264	extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree);
2265
2266	BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops;
2267
2268	BTRFS_I(fs_info->btree_inode)->root = tree_root;
2269	memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
2270	       sizeof(struct btrfs_key));
2271	set_bit(BTRFS_INODE_DUMMY,
2272		&BTRFS_I(fs_info->btree_inode)->runtime_flags);
2273	btrfs_insert_inode_hash(fs_info->btree_inode);
2274}
2275
2276static void btrfs_init_dev_replace_locks(struct btrfs_fs_info *fs_info)
2277{
2278	fs_info->dev_replace.lock_owner = 0;
2279	atomic_set(&fs_info->dev_replace.nesting_level, 0);
2280	mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount);
2281	rwlock_init(&fs_info->dev_replace.lock);
2282	atomic_set(&fs_info->dev_replace.read_locks, 0);
2283	atomic_set(&fs_info->dev_replace.blocking_readers, 0);
2284	init_waitqueue_head(&fs_info->replace_wait);
2285	init_waitqueue_head(&fs_info->dev_replace.read_lock_wq);
2286}
2287
2288static void btrfs_init_qgroup(struct btrfs_fs_info *fs_info)
2289{
2290	spin_lock_init(&fs_info->qgroup_lock);
2291	mutex_init(&fs_info->qgroup_ioctl_lock);
2292	fs_info->qgroup_tree = RB_ROOT;
2293	fs_info->qgroup_op_tree = RB_ROOT;
2294	INIT_LIST_HEAD(&fs_info->dirty_qgroups);
2295	fs_info->qgroup_seq = 1;
2296	fs_info->quota_enabled = 0;
2297	fs_info->pending_quota_state = 0;
2298	fs_info->qgroup_ulist = NULL;
 
2299	mutex_init(&fs_info->qgroup_rescan_lock);
2300}
2301
2302static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info,
2303		struct btrfs_fs_devices *fs_devices)
2304{
2305	int max_active = fs_info->thread_pool_size;
2306	unsigned int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND;
2307
2308	fs_info->workers =
2309		btrfs_alloc_workqueue("worker", flags | WQ_HIGHPRI,
2310				      max_active, 16);
2311
2312	fs_info->delalloc_workers =
2313		btrfs_alloc_workqueue("delalloc", flags, max_active, 2);
 
2314
2315	fs_info->flush_workers =
2316		btrfs_alloc_workqueue("flush_delalloc", flags, max_active, 0);
 
2317
2318	fs_info->caching_workers =
2319		btrfs_alloc_workqueue("cache", flags, max_active, 0);
2320
2321	/*
2322	 * a higher idle thresh on the submit workers makes it much more
2323	 * likely that bios will be send down in a sane order to the
2324	 * devices
2325	 */
2326	fs_info->submit_workers =
2327		btrfs_alloc_workqueue("submit", flags,
2328				      min_t(u64, fs_devices->num_devices,
2329					    max_active), 64);
2330
2331	fs_info->fixup_workers =
2332		btrfs_alloc_workqueue("fixup", flags, 1, 0);
2333
2334	/*
2335	 * endios are largely parallel and should have a very
2336	 * low idle thresh
2337	 */
2338	fs_info->endio_workers =
2339		btrfs_alloc_workqueue("endio", flags, max_active, 4);
2340	fs_info->endio_meta_workers =
2341		btrfs_alloc_workqueue("endio-meta", flags, max_active, 4);
 
2342	fs_info->endio_meta_write_workers =
2343		btrfs_alloc_workqueue("endio-meta-write", flags, max_active, 2);
 
2344	fs_info->endio_raid56_workers =
2345		btrfs_alloc_workqueue("endio-raid56", flags, max_active, 4);
 
2346	fs_info->endio_repair_workers =
2347		btrfs_alloc_workqueue("endio-repair", flags, 1, 0);
2348	fs_info->rmw_workers =
2349		btrfs_alloc_workqueue("rmw", flags, max_active, 2);
2350	fs_info->endio_write_workers =
2351		btrfs_alloc_workqueue("endio-write", flags, max_active, 2);
 
2352	fs_info->endio_freespace_worker =
2353		btrfs_alloc_workqueue("freespace-write", flags, max_active, 0);
 
2354	fs_info->delayed_workers =
2355		btrfs_alloc_workqueue("delayed-meta", flags, max_active, 0);
 
2356	fs_info->readahead_workers =
2357		btrfs_alloc_workqueue("readahead", flags, max_active, 2);
 
2358	fs_info->qgroup_rescan_workers =
2359		btrfs_alloc_workqueue("qgroup-rescan", flags, 1, 0);
2360	fs_info->extent_workers =
2361		btrfs_alloc_workqueue("extent-refs", flags,
2362				      min_t(u64, fs_devices->num_devices,
2363					    max_active), 8);
2364
2365	if (!(fs_info->workers && fs_info->delalloc_workers &&
2366	      fs_info->submit_workers && fs_info->flush_workers &&
2367	      fs_info->endio_workers && fs_info->endio_meta_workers &&
2368	      fs_info->endio_meta_write_workers &&
2369	      fs_info->endio_repair_workers &&
2370	      fs_info->endio_write_workers && fs_info->endio_raid56_workers &&
2371	      fs_info->endio_freespace_worker && fs_info->rmw_workers &&
2372	      fs_info->caching_workers && fs_info->readahead_workers &&
2373	      fs_info->fixup_workers && fs_info->delayed_workers &&
2374	      fs_info->extent_workers &&
2375	      fs_info->qgroup_rescan_workers)) {
2376		return -ENOMEM;
2377	}
2378
2379	return 0;
2380}
2381
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2382static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
2383			    struct btrfs_fs_devices *fs_devices)
2384{
2385	int ret;
2386	struct btrfs_root *tree_root = fs_info->tree_root;
2387	struct btrfs_root *log_tree_root;
2388	struct btrfs_super_block *disk_super = fs_info->super_copy;
2389	u64 bytenr = btrfs_super_log_root(disk_super);
 
2390
2391	if (fs_devices->rw_devices == 0) {
2392		btrfs_warn(fs_info, "log replay required on RO media");
2393		return -EIO;
2394	}
2395
2396	log_tree_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
2397	if (!log_tree_root)
2398		return -ENOMEM;
2399
2400	__setup_root(tree_root->nodesize, tree_root->sectorsize,
2401			tree_root->stripesize, log_tree_root, fs_info,
2402			BTRFS_TREE_LOG_OBJECTID);
2403
2404	log_tree_root->node = read_tree_block(tree_root, bytenr,
2405			fs_info->generation + 1);
 
2406	if (IS_ERR(log_tree_root->node)) {
2407		btrfs_warn(fs_info, "failed to read log tree");
2408		ret = PTR_ERR(log_tree_root->node);
2409		kfree(log_tree_root);
2410		return ret;
2411	} else if (!extent_buffer_uptodate(log_tree_root->node)) {
2412		btrfs_err(fs_info, "failed to read log tree");
2413		free_extent_buffer(log_tree_root->node);
2414		kfree(log_tree_root);
2415		return -EIO;
2416	}
2417	/* returns with log_tree_root freed on success */
2418	ret = btrfs_recover_log_trees(log_tree_root);
2419	if (ret) {
2420		btrfs_std_error(tree_root->fs_info, ret,
2421			    "Failed to recover log tree");
2422		free_extent_buffer(log_tree_root->node);
2423		kfree(log_tree_root);
2424		return ret;
2425	}
2426
2427	if (fs_info->sb->s_flags & MS_RDONLY) {
2428		ret = btrfs_commit_super(tree_root);
2429		if (ret)
2430			return ret;
2431	}
2432
2433	return 0;
2434}
2435
2436static int btrfs_read_roots(struct btrfs_fs_info *fs_info,
2437			    struct btrfs_root *tree_root)
2438{
 
2439	struct btrfs_root *root;
2440	struct btrfs_key location;
2441	int ret;
2442
 
 
2443	location.objectid = BTRFS_EXTENT_TREE_OBJECTID;
2444	location.type = BTRFS_ROOT_ITEM_KEY;
2445	location.offset = 0;
2446
2447	root = btrfs_read_tree_root(tree_root, &location);
2448	if (IS_ERR(root))
2449		return PTR_ERR(root);
 
 
2450	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2451	fs_info->extent_root = root;
2452
2453	location.objectid = BTRFS_DEV_TREE_OBJECTID;
2454	root = btrfs_read_tree_root(tree_root, &location);
2455	if (IS_ERR(root))
2456		return PTR_ERR(root);
 
 
2457	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2458	fs_info->dev_root = root;
2459	btrfs_init_devices_late(fs_info);
2460
2461	location.objectid = BTRFS_CSUM_TREE_OBJECTID;
2462	root = btrfs_read_tree_root(tree_root, &location);
2463	if (IS_ERR(root))
2464		return PTR_ERR(root);
 
 
2465	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2466	fs_info->csum_root = root;
2467
2468	location.objectid = BTRFS_QUOTA_TREE_OBJECTID;
2469	root = btrfs_read_tree_root(tree_root, &location);
2470	if (!IS_ERR(root)) {
2471		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2472		fs_info->quota_enabled = 1;
2473		fs_info->pending_quota_state = 1;
2474		fs_info->quota_root = root;
2475	}
2476
2477	location.objectid = BTRFS_UUID_TREE_OBJECTID;
2478	root = btrfs_read_tree_root(tree_root, &location);
2479	if (IS_ERR(root)) {
2480		ret = PTR_ERR(root);
2481		if (ret != -ENOENT)
2482			return ret;
2483	} else {
2484		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2485		fs_info->uuid_root = root;
2486	}
2487
2488	if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
2489		location.objectid = BTRFS_FREE_SPACE_TREE_OBJECTID;
2490		root = btrfs_read_tree_root(tree_root, &location);
2491		if (IS_ERR(root))
2492			return PTR_ERR(root);
 
 
2493		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2494		fs_info->free_space_root = root;
2495	}
2496
2497	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2498}
2499
2500int open_ctree(struct super_block *sb,
2501	       struct btrfs_fs_devices *fs_devices,
2502	       char *options)
2503{
2504	u32 sectorsize;
2505	u32 nodesize;
2506	u32 stripesize;
2507	u64 generation;
2508	u64 features;
 
2509	struct btrfs_key location;
2510	struct buffer_head *bh;
2511	struct btrfs_super_block *disk_super;
2512	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
2513	struct btrfs_root *tree_root;
2514	struct btrfs_root *chunk_root;
2515	int ret;
2516	int err = -EINVAL;
2517	int num_backups_tried = 0;
2518	int backup_index = 0;
2519	int max_active;
 
2520
2521	tree_root = fs_info->tree_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
2522	chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
2523	if (!tree_root || !chunk_root) {
2524		err = -ENOMEM;
2525		goto fail;
2526	}
2527
2528	ret = init_srcu_struct(&fs_info->subvol_srcu);
2529	if (ret) {
2530		err = ret;
2531		goto fail;
2532	}
2533
2534	ret = setup_bdi(fs_info, &fs_info->bdi);
2535	if (ret) {
2536		err = ret;
2537		goto fail_srcu;
2538	}
2539
2540	ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0, GFP_KERNEL);
2541	if (ret) {
2542		err = ret;
2543		goto fail_bdi;
2544	}
2545	fs_info->dirty_metadata_batch = PAGE_SIZE *
2546					(1 + ilog2(nr_cpu_ids));
2547
2548	ret = percpu_counter_init(&fs_info->delalloc_bytes, 0, GFP_KERNEL);
2549	if (ret) {
2550		err = ret;
2551		goto fail_dirty_metadata_bytes;
2552	}
2553
2554	ret = percpu_counter_init(&fs_info->bio_counter, 0, GFP_KERNEL);
 
2555	if (ret) {
2556		err = ret;
2557		goto fail_delalloc_bytes;
2558	}
2559
2560	fs_info->btree_inode = new_inode(sb);
2561	if (!fs_info->btree_inode) {
2562		err = -ENOMEM;
2563		goto fail_bio_counter;
2564	}
2565
2566	mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
2567
2568	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
2569	INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC);
2570	INIT_LIST_HEAD(&fs_info->trans_list);
2571	INIT_LIST_HEAD(&fs_info->dead_roots);
2572	INIT_LIST_HEAD(&fs_info->delayed_iputs);
2573	INIT_LIST_HEAD(&fs_info->delalloc_roots);
2574	INIT_LIST_HEAD(&fs_info->caching_block_groups);
2575	spin_lock_init(&fs_info->delalloc_root_lock);
2576	spin_lock_init(&fs_info->trans_lock);
2577	spin_lock_init(&fs_info->fs_roots_radix_lock);
2578	spin_lock_init(&fs_info->delayed_iput_lock);
2579	spin_lock_init(&fs_info->defrag_inodes_lock);
2580	spin_lock_init(&fs_info->free_chunk_lock);
2581	spin_lock_init(&fs_info->tree_mod_seq_lock);
2582	spin_lock_init(&fs_info->super_lock);
2583	spin_lock_init(&fs_info->qgroup_op_lock);
2584	spin_lock_init(&fs_info->buffer_lock);
2585	spin_lock_init(&fs_info->unused_bgs_lock);
2586	rwlock_init(&fs_info->tree_mod_log_lock);
2587	mutex_init(&fs_info->unused_bg_unpin_mutex);
2588	mutex_init(&fs_info->delete_unused_bgs_mutex);
2589	mutex_init(&fs_info->reloc_mutex);
2590	mutex_init(&fs_info->delalloc_root_mutex);
2591	mutex_init(&fs_info->cleaner_delayed_iput_mutex);
2592	seqlock_init(&fs_info->profiles_lock);
2593
2594	INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
2595	INIT_LIST_HEAD(&fs_info->space_info);
2596	INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
2597	INIT_LIST_HEAD(&fs_info->unused_bgs);
2598	btrfs_mapping_init(&fs_info->mapping_tree);
2599	btrfs_init_block_rsv(&fs_info->global_block_rsv,
2600			     BTRFS_BLOCK_RSV_GLOBAL);
2601	btrfs_init_block_rsv(&fs_info->delalloc_block_rsv,
2602			     BTRFS_BLOCK_RSV_DELALLOC);
2603	btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
2604	btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK);
2605	btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY);
2606	btrfs_init_block_rsv(&fs_info->delayed_block_rsv,
2607			     BTRFS_BLOCK_RSV_DELOPS);
2608	atomic_set(&fs_info->nr_async_submits, 0);
 
 
2609	atomic_set(&fs_info->async_delalloc_pages, 0);
2610	atomic_set(&fs_info->async_submit_draining, 0);
2611	atomic_set(&fs_info->nr_async_bios, 0);
2612	atomic_set(&fs_info->defrag_running, 0);
2613	atomic_set(&fs_info->qgroup_op_seq, 0);
2614	atomic_set(&fs_info->reada_works_cnt, 0);
 
2615	atomic64_set(&fs_info->tree_mod_seq, 0);
2616	fs_info->sb = sb;
2617	fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE;
2618	fs_info->metadata_ratio = 0;
2619	fs_info->defrag_inodes = RB_ROOT;
2620	fs_info->free_chunk_space = 0;
2621	fs_info->tree_mod_log = RB_ROOT;
2622	fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
2623	fs_info->avg_delayed_ref_runtime = NSEC_PER_SEC >> 6; /* div by 64 */
2624	/* readahead state */
2625	INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
2626	spin_lock_init(&fs_info->reada_lock);
 
2627
2628	fs_info->thread_pool_size = min_t(unsigned long,
2629					  num_online_cpus() + 2, 8);
2630
2631	INIT_LIST_HEAD(&fs_info->ordered_roots);
2632	spin_lock_init(&fs_info->ordered_root_lock);
 
 
 
 
 
 
 
 
2633	fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
2634					GFP_KERNEL);
2635	if (!fs_info->delayed_root) {
2636		err = -ENOMEM;
2637		goto fail_iput;
2638	}
2639	btrfs_init_delayed_root(fs_info->delayed_root);
2640
2641	btrfs_init_scrub(fs_info);
2642#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
2643	fs_info->check_integrity_print_mask = 0;
2644#endif
2645	btrfs_init_balance(fs_info);
2646	btrfs_init_async_reclaim_work(&fs_info->async_reclaim_work);
2647
2648	sb->s_blocksize = 4096;
2649	sb->s_blocksize_bits = blksize_bits(4096);
2650	sb->s_bdi = &fs_info->bdi;
2651
2652	btrfs_init_btree_inode(fs_info, tree_root);
2653
2654	spin_lock_init(&fs_info->block_group_cache_lock);
2655	fs_info->block_group_cache_tree = RB_ROOT;
2656	fs_info->first_logical_byte = (u64)-1;
2657
2658	extent_io_tree_init(&fs_info->freed_extents[0],
2659			     fs_info->btree_inode->i_mapping);
2660	extent_io_tree_init(&fs_info->freed_extents[1],
2661			     fs_info->btree_inode->i_mapping);
2662	fs_info->pinned_extents = &fs_info->freed_extents[0];
2663	fs_info->do_barriers = 1;
2664
2665
2666	mutex_init(&fs_info->ordered_operations_mutex);
2667	mutex_init(&fs_info->tree_log_mutex);
2668	mutex_init(&fs_info->chunk_mutex);
2669	mutex_init(&fs_info->transaction_kthread_mutex);
2670	mutex_init(&fs_info->cleaner_mutex);
2671	mutex_init(&fs_info->volume_mutex);
2672	mutex_init(&fs_info->ro_block_group_mutex);
2673	init_rwsem(&fs_info->commit_root_sem);
2674	init_rwsem(&fs_info->cleanup_work_sem);
2675	init_rwsem(&fs_info->subvol_sem);
2676	sema_init(&fs_info->uuid_tree_rescan_sem, 1);
2677
2678	btrfs_init_dev_replace_locks(fs_info);
2679	btrfs_init_qgroup(fs_info);
2680
2681	btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
2682	btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
2683
2684	init_waitqueue_head(&fs_info->transaction_throttle);
2685	init_waitqueue_head(&fs_info->transaction_wait);
2686	init_waitqueue_head(&fs_info->transaction_blocked_wait);
2687	init_waitqueue_head(&fs_info->async_submit_wait);
 
2688
2689	INIT_LIST_HEAD(&fs_info->pinned_chunks);
 
 
 
 
 
 
 
 
2690
2691	ret = btrfs_alloc_stripe_hash_table(fs_info);
2692	if (ret) {
2693		err = ret;
2694		goto fail_alloc;
2695	}
2696
2697	__setup_root(4096, 4096, 4096, tree_root,
2698		     fs_info, BTRFS_ROOT_TREE_OBJECTID);
2699
2700	invalidate_bdev(fs_devices->latest_bdev);
2701
2702	/*
2703	 * Read super block and check the signature bytes only
2704	 */
2705	bh = btrfs_read_dev_super(fs_devices->latest_bdev);
2706	if (IS_ERR(bh)) {
2707		err = PTR_ERR(bh);
2708		goto fail_alloc;
2709	}
2710
2711	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2712	 * We want to check superblock checksum, the type is stored inside.
2713	 * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k).
2714	 */
2715	if (btrfs_check_super_csum(bh->b_data)) {
2716		printk(KERN_ERR "BTRFS: superblock checksum mismatch\n");
2717		err = -EINVAL;
2718		brelse(bh);
2719		goto fail_alloc;
2720	}
2721
2722	/*
2723	 * super_copy is zeroed at allocation time and we never touch the
2724	 * following bytes up to INFO_SIZE, the checksum is calculated from
2725	 * the whole block of INFO_SIZE
2726	 */
2727	memcpy(fs_info->super_copy, bh->b_data, sizeof(*fs_info->super_copy));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2728	memcpy(fs_info->super_for_commit, fs_info->super_copy,
2729	       sizeof(*fs_info->super_for_commit));
2730	brelse(bh);
2731
2732	memcpy(fs_info->fsid, fs_info->super_copy->fsid, BTRFS_FSID_SIZE);
2733
2734	ret = btrfs_check_super_valid(fs_info, sb->s_flags & MS_RDONLY);
2735	if (ret) {
2736		printk(KERN_ERR "BTRFS: superblock contains fatal errors\n");
2737		err = -EINVAL;
2738		goto fail_alloc;
2739	}
2740
2741	disk_super = fs_info->super_copy;
2742	if (!btrfs_super_root(disk_super))
2743		goto fail_alloc;
2744
2745	/* check FS state, whether FS is broken. */
2746	if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
2747		set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state);
2748
2749	/*
2750	 * run through our array of backup supers and setup
2751	 * our ring pointer to the oldest one
2752	 */
2753	generation = btrfs_super_generation(disk_super);
2754	find_oldest_super_backup(fs_info, generation);
2755
2756	/*
2757	 * In the long term, we'll store the compression type in the super
2758	 * block, and it'll be used for per file compression control.
2759	 */
2760	fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
2761
2762	ret = btrfs_parse_options(tree_root, options, sb->s_flags);
2763	if (ret) {
2764		err = ret;
2765		goto fail_alloc;
2766	}
2767
2768	features = btrfs_super_incompat_flags(disk_super) &
2769		~BTRFS_FEATURE_INCOMPAT_SUPP;
2770	if (features) {
2771		printk(KERN_ERR "BTRFS: couldn't mount because of "
2772		       "unsupported optional features (%Lx).\n",
2773		       features);
2774		err = -EINVAL;
2775		goto fail_alloc;
2776	}
2777
2778	features = btrfs_super_incompat_flags(disk_super);
2779	features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
2780	if (tree_root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
2781		features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
 
 
2782
2783	if (features & BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA)
2784		printk(KERN_INFO "BTRFS: has skinny extents\n");
2785
2786	/*
2787	 * flag our filesystem as having big metadata blocks if
2788	 * they are bigger than the page size
2789	 */
2790	if (btrfs_super_nodesize(disk_super) > PAGE_SIZE) {
2791		if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA))
2792			printk(KERN_INFO "BTRFS: flagging fs with big metadata feature\n");
 
2793		features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
2794	}
2795
2796	nodesize = btrfs_super_nodesize(disk_super);
2797	sectorsize = btrfs_super_sectorsize(disk_super);
2798	stripesize = btrfs_super_stripesize(disk_super);
2799	fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids));
2800	fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
2801
 
 
 
 
 
2802	/*
2803	 * mixed block groups end up with duplicate but slightly offset
2804	 * extent buffers for the same range.  It leads to corruptions
2805	 */
2806	if ((features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
2807	    (sectorsize != nodesize)) {
2808		printk(KERN_ERR "BTRFS: unequal leaf/node/sector sizes "
2809				"are not allowed for mixed block groups on %s\n",
2810				sb->s_id);
2811		goto fail_alloc;
2812	}
2813
2814	/*
2815	 * Needn't use the lock because there is no other task which will
2816	 * update the flag.
2817	 */
2818	btrfs_set_super_incompat_flags(disk_super, features);
2819
2820	features = btrfs_super_compat_ro_flags(disk_super) &
2821		~BTRFS_FEATURE_COMPAT_RO_SUPP;
2822	if (!(sb->s_flags & MS_RDONLY) && features) {
2823		printk(KERN_ERR "BTRFS: couldn't mount RDWR because of "
2824		       "unsupported option features (%Lx).\n",
2825		       features);
2826		err = -EINVAL;
2827		goto fail_alloc;
2828	}
2829
2830	max_active = fs_info->thread_pool_size;
2831
2832	ret = btrfs_init_workqueues(fs_info, fs_devices);
2833	if (ret) {
2834		err = ret;
2835		goto fail_sb_buffer;
2836	}
2837
2838	fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
2839	fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
2840				    SZ_4M / PAGE_SIZE);
2841
2842	tree_root->nodesize = nodesize;
2843	tree_root->sectorsize = sectorsize;
2844	tree_root->stripesize = stripesize;
2845
2846	sb->s_blocksize = sectorsize;
2847	sb->s_blocksize_bits = blksize_bits(sectorsize);
 
2848
2849	mutex_lock(&fs_info->chunk_mutex);
2850	ret = btrfs_read_sys_array(tree_root);
2851	mutex_unlock(&fs_info->chunk_mutex);
2852	if (ret) {
2853		printk(KERN_ERR "BTRFS: failed to read the system "
2854		       "array on %s\n", sb->s_id);
2855		goto fail_sb_buffer;
2856	}
2857
2858	generation = btrfs_super_chunk_root_generation(disk_super);
 
2859
2860	__setup_root(nodesize, sectorsize, stripesize, chunk_root,
2861		     fs_info, BTRFS_CHUNK_TREE_OBJECTID);
2862
2863	chunk_root->node = read_tree_block(chunk_root,
2864					   btrfs_super_chunk_root(disk_super),
2865					   generation);
2866	if (IS_ERR(chunk_root->node) ||
2867	    !extent_buffer_uptodate(chunk_root->node)) {
2868		printk(KERN_ERR "BTRFS: failed to read chunk root on %s\n",
2869		       sb->s_id);
2870		if (!IS_ERR(chunk_root->node))
2871			free_extent_buffer(chunk_root->node);
2872		chunk_root->node = NULL;
2873		goto fail_tree_roots;
2874	}
2875	btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
2876	chunk_root->commit_root = btrfs_root_node(chunk_root);
2877
2878	read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
2879	   btrfs_header_chunk_tree_uuid(chunk_root->node), BTRFS_UUID_SIZE);
2880
2881	ret = btrfs_read_chunk_tree(chunk_root);
2882	if (ret) {
2883		printk(KERN_ERR "BTRFS: failed to read chunk tree on %s\n",
2884		       sb->s_id);
2885		goto fail_tree_roots;
2886	}
2887
2888	/*
2889	 * keep the device that is marked to be the target device for the
2890	 * dev_replace procedure
2891	 */
2892	btrfs_close_extra_devices(fs_devices, 0);
2893
2894	if (!fs_devices->latest_bdev) {
2895		printk(KERN_ERR "BTRFS: failed to read devices on %s\n",
2896		       sb->s_id);
2897		goto fail_tree_roots;
2898	}
2899
2900retry_root_backup:
2901	generation = btrfs_super_generation(disk_super);
 
2902
2903	tree_root->node = read_tree_block(tree_root,
2904					  btrfs_super_root(disk_super),
2905					  generation);
2906	if (IS_ERR(tree_root->node) ||
2907	    !extent_buffer_uptodate(tree_root->node)) {
2908		printk(KERN_WARNING "BTRFS: failed to read tree root on %s\n",
2909		       sb->s_id);
2910		if (!IS_ERR(tree_root->node))
2911			free_extent_buffer(tree_root->node);
2912		tree_root->node = NULL;
2913		goto recovery_tree_root;
2914	}
2915
2916	btrfs_set_root_node(&tree_root->root_item, tree_root->node);
2917	tree_root->commit_root = btrfs_root_node(tree_root);
2918	btrfs_set_root_refs(&tree_root->root_item, 1);
2919
2920	mutex_lock(&tree_root->objectid_mutex);
2921	ret = btrfs_find_highest_objectid(tree_root,
2922					&tree_root->highest_objectid);
2923	if (ret) {
2924		mutex_unlock(&tree_root->objectid_mutex);
2925		goto recovery_tree_root;
2926	}
2927
2928	ASSERT(tree_root->highest_objectid <= BTRFS_LAST_FREE_OBJECTID);
2929
2930	mutex_unlock(&tree_root->objectid_mutex);
2931
2932	ret = btrfs_read_roots(fs_info, tree_root);
2933	if (ret)
2934		goto recovery_tree_root;
2935
2936	fs_info->generation = generation;
2937	fs_info->last_trans_committed = generation;
2938
 
 
 
 
 
 
 
2939	ret = btrfs_recover_balance(fs_info);
2940	if (ret) {
2941		printk(KERN_ERR "BTRFS: failed to recover balance\n");
2942		goto fail_block_groups;
2943	}
2944
2945	ret = btrfs_init_dev_stats(fs_info);
2946	if (ret) {
2947		printk(KERN_ERR "BTRFS: failed to init dev_stats: %d\n",
2948		       ret);
2949		goto fail_block_groups;
2950	}
2951
2952	ret = btrfs_init_dev_replace(fs_info);
2953	if (ret) {
2954		pr_err("BTRFS: failed to init dev_replace: %d\n", ret);
2955		goto fail_block_groups;
2956	}
2957
2958	btrfs_close_extra_devices(fs_devices, 1);
2959
2960	ret = btrfs_sysfs_add_fsid(fs_devices, NULL);
2961	if (ret) {
2962		pr_err("BTRFS: failed to init sysfs fsid interface: %d\n", ret);
 
2963		goto fail_block_groups;
2964	}
2965
2966	ret = btrfs_sysfs_add_device(fs_devices);
2967	if (ret) {
2968		pr_err("BTRFS: failed to init sysfs device interface: %d\n", ret);
 
2969		goto fail_fsdev_sysfs;
2970	}
2971
2972	ret = btrfs_sysfs_add_mounted(fs_info);
2973	if (ret) {
2974		pr_err("BTRFS: failed to init sysfs interface: %d\n", ret);
2975		goto fail_fsdev_sysfs;
2976	}
2977
2978	ret = btrfs_init_space_info(fs_info);
2979	if (ret) {
2980		printk(KERN_ERR "BTRFS: Failed to initial space info: %d\n", ret);
2981		goto fail_sysfs;
2982	}
2983
2984	ret = btrfs_read_block_groups(fs_info->extent_root);
2985	if (ret) {
2986		printk(KERN_ERR "BTRFS: Failed to read block groups: %d\n", ret);
2987		goto fail_sysfs;
2988	}
2989	fs_info->num_tolerated_disk_barrier_failures =
2990		btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
2991	if (fs_info->fs_devices->missing_devices >
2992	     fs_info->num_tolerated_disk_barrier_failures &&
2993	    !(sb->s_flags & MS_RDONLY)) {
2994		pr_warn("BTRFS: missing devices(%llu) exceeds the limit(%d), writeable mount is not allowed\n",
2995			fs_info->fs_devices->missing_devices,
2996			fs_info->num_tolerated_disk_barrier_failures);
2997		goto fail_sysfs;
2998	}
2999
3000	fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
3001					       "btrfs-cleaner");
3002	if (IS_ERR(fs_info->cleaner_kthread))
3003		goto fail_sysfs;
3004
3005	fs_info->transaction_kthread = kthread_run(transaction_kthread,
3006						   tree_root,
3007						   "btrfs-transaction");
3008	if (IS_ERR(fs_info->transaction_kthread))
3009		goto fail_cleaner;
3010
3011	if (!btrfs_test_opt(tree_root, SSD) &&
3012	    !btrfs_test_opt(tree_root, NOSSD) &&
3013	    !fs_info->fs_devices->rotating) {
3014		printk(KERN_INFO "BTRFS: detected SSD devices, enabling SSD "
3015		       "mode\n");
3016		btrfs_set_opt(fs_info->mount_opt, SSD);
3017	}
3018
3019	/*
3020	 * Mount does not set all options immediatelly, we can do it now and do
3021	 * not have to wait for transaction commit
3022	 */
3023	btrfs_apply_pending_changes(fs_info);
3024
3025#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3026	if (btrfs_test_opt(tree_root, CHECK_INTEGRITY)) {
3027		ret = btrfsic_mount(tree_root, fs_devices,
3028				    btrfs_test_opt(tree_root,
3029					CHECK_INTEGRITY_INCLUDING_EXTENT_DATA) ?
3030				    1 : 0,
3031				    fs_info->check_integrity_print_mask);
3032		if (ret)
3033			printk(KERN_WARNING "BTRFS: failed to initialize"
3034			       " integrity check module %s\n", sb->s_id);
 
3035	}
3036#endif
3037	ret = btrfs_read_qgroup_config(fs_info);
3038	if (ret)
3039		goto fail_trans_kthread;
3040
 
 
 
3041	/* do not make disk changes in broken FS or nologreplay is given */
3042	if (btrfs_super_log_root(disk_super) != 0 &&
3043	    !btrfs_test_opt(tree_root, NOLOGREPLAY)) {
3044		ret = btrfs_replay_log(fs_info, fs_devices);
3045		if (ret) {
3046			err = ret;
3047			goto fail_qgroup;
3048		}
3049	}
3050
3051	ret = btrfs_find_orphan_roots(tree_root);
3052	if (ret)
3053		goto fail_qgroup;
3054
3055	if (!(sb->s_flags & MS_RDONLY)) {
3056		ret = btrfs_cleanup_fs_roots(fs_info);
3057		if (ret)
3058			goto fail_qgroup;
3059
3060		mutex_lock(&fs_info->cleaner_mutex);
3061		ret = btrfs_recover_relocation(tree_root);
3062		mutex_unlock(&fs_info->cleaner_mutex);
3063		if (ret < 0) {
3064			printk(KERN_WARNING
3065			       "BTRFS: failed to recover relocation\n");
3066			err = -EINVAL;
3067			goto fail_qgroup;
3068		}
3069	}
3070
3071	location.objectid = BTRFS_FS_TREE_OBJECTID;
3072	location.type = BTRFS_ROOT_ITEM_KEY;
3073	location.offset = 0;
3074
3075	fs_info->fs_root = btrfs_read_fs_root_no_name(fs_info, &location);
3076	if (IS_ERR(fs_info->fs_root)) {
3077		err = PTR_ERR(fs_info->fs_root);
 
3078		goto fail_qgroup;
3079	}
3080
3081	if (sb->s_flags & MS_RDONLY)
3082		return 0;
3083
3084	if (btrfs_test_opt(tree_root, FREE_SPACE_TREE) &&
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3085	    !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3086		pr_info("BTRFS: creating free space tree\n");
3087		ret = btrfs_create_free_space_tree(fs_info);
3088		if (ret) {
3089			pr_warn("BTRFS: failed to create free space tree %d\n",
3090				ret);
3091			close_ctree(tree_root);
3092			return ret;
3093		}
3094	}
3095
3096	down_read(&fs_info->cleanup_work_sem);
3097	if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) ||
3098	    (ret = btrfs_orphan_cleanup(fs_info->tree_root))) {
3099		up_read(&fs_info->cleanup_work_sem);
3100		close_ctree(tree_root);
3101		return ret;
3102	}
3103	up_read(&fs_info->cleanup_work_sem);
3104
3105	ret = btrfs_resume_balance_async(fs_info);
3106	if (ret) {
3107		printk(KERN_WARNING "BTRFS: failed to resume balance\n");
3108		close_ctree(tree_root);
3109		return ret;
3110	}
3111
3112	ret = btrfs_resume_dev_replace_async(fs_info);
3113	if (ret) {
3114		pr_warn("BTRFS: failed to resume dev_replace\n");
3115		close_ctree(tree_root);
3116		return ret;
3117	}
3118
3119	btrfs_qgroup_rescan_resume(fs_info);
3120
3121	if (btrfs_test_opt(tree_root, CLEAR_CACHE) &&
3122	    btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3123		pr_info("BTRFS: clearing free space tree\n");
3124		ret = btrfs_clear_free_space_tree(fs_info);
3125		if (ret) {
3126			pr_warn("BTRFS: failed to clear free space tree %d\n",
3127				ret);
3128			close_ctree(tree_root);
3129			return ret;
3130		}
3131	}
3132
3133	if (!fs_info->uuid_root) {
3134		pr_info("BTRFS: creating UUID tree\n");
3135		ret = btrfs_create_uuid_tree(fs_info);
3136		if (ret) {
3137			pr_warn("BTRFS: failed to create the UUID tree %d\n",
3138				ret);
3139			close_ctree(tree_root);
3140			return ret;
3141		}
3142	} else if (btrfs_test_opt(tree_root, RESCAN_UUID_TREE) ||
3143		   fs_info->generation !=
3144				btrfs_super_uuid_tree_generation(disk_super)) {
3145		pr_info("BTRFS: checking UUID tree\n");
3146		ret = btrfs_check_uuid_tree(fs_info);
3147		if (ret) {
3148			pr_warn("BTRFS: failed to check the UUID tree %d\n",
3149				ret);
3150			close_ctree(tree_root);
3151			return ret;
3152		}
3153	} else {
3154		fs_info->update_uuid_tree_gen = 1;
3155	}
3156
3157	fs_info->open = 1;
3158
3159	/*
3160	 * backuproot only affect mount behavior, and if open_ctree succeeded,
3161	 * no need to keep the flag
3162	 */
3163	btrfs_clear_opt(fs_info->mount_opt, USEBACKUPROOT);
3164
3165	return 0;
3166
3167fail_qgroup:
3168	btrfs_free_qgroup_config(fs_info);
3169fail_trans_kthread:
3170	kthread_stop(fs_info->transaction_kthread);
3171	btrfs_cleanup_transaction(fs_info->tree_root);
3172	btrfs_free_fs_roots(fs_info);
3173fail_cleaner:
3174	kthread_stop(fs_info->cleaner_kthread);
3175
3176	/*
3177	 * make sure we're done with the btree inode before we stop our
3178	 * kthreads
3179	 */
3180	filemap_write_and_wait(fs_info->btree_inode->i_mapping);
3181
3182fail_sysfs:
3183	btrfs_sysfs_remove_mounted(fs_info);
3184
3185fail_fsdev_sysfs:
3186	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
3187
3188fail_block_groups:
3189	btrfs_put_block_group_cache(fs_info);
3190	btrfs_free_block_groups(fs_info);
3191
3192fail_tree_roots:
3193	free_root_pointers(fs_info, 1);
3194	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
3195
3196fail_sb_buffer:
3197	btrfs_stop_all_workers(fs_info);
 
 
 
3198fail_alloc:
3199fail_iput:
3200	btrfs_mapping_tree_free(&fs_info->mapping_tree);
3201
3202	iput(fs_info->btree_inode);
3203fail_bio_counter:
3204	percpu_counter_destroy(&fs_info->bio_counter);
3205fail_delalloc_bytes:
3206	percpu_counter_destroy(&fs_info->delalloc_bytes);
3207fail_dirty_metadata_bytes:
3208	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
3209fail_bdi:
3210	bdi_destroy(&fs_info->bdi);
3211fail_srcu:
3212	cleanup_srcu_struct(&fs_info->subvol_srcu);
3213fail:
3214	btrfs_free_stripe_hash_table(fs_info);
3215	btrfs_close_devices(fs_info->fs_devices);
3216	return err;
3217
3218recovery_tree_root:
3219	if (!btrfs_test_opt(tree_root, USEBACKUPROOT))
3220		goto fail_tree_roots;
3221
3222	free_root_pointers(fs_info, 0);
3223
3224	/* don't use the log in recovery mode, it won't be valid */
3225	btrfs_set_super_log_root(disk_super, 0);
3226
3227	/* we can't trust the free space cache either */
3228	btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
3229
3230	ret = next_root_backup(fs_info, fs_info->super_copy,
3231			       &num_backups_tried, &backup_index);
3232	if (ret == -1)
3233		goto fail_block_groups;
3234	goto retry_root_backup;
3235}
 
3236
3237static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
3238{
3239	if (uptodate) {
3240		set_buffer_uptodate(bh);
3241	} else {
3242		struct btrfs_device *device = (struct btrfs_device *)
3243			bh->b_private;
3244
3245		btrfs_warn_rl_in_rcu(device->dev_root->fs_info,
3246				"lost page write due to IO error on %s",
3247					  rcu_str_deref(device->name));
3248		/* note, we dont' set_buffer_write_io_error because we have
3249		 * our own ways of dealing with the IO errors
3250		 */
3251		clear_buffer_uptodate(bh);
3252		btrfs_dev_stat_inc_and_print(device, BTRFS_DEV_STAT_WRITE_ERRS);
3253	}
3254	unlock_buffer(bh);
3255	put_bh(bh);
3256}
3257
3258int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num,
3259			struct buffer_head **bh_ret)
3260{
3261	struct buffer_head *bh;
3262	struct btrfs_super_block *super;
3263	u64 bytenr;
3264
3265	bytenr = btrfs_sb_offset(copy_num);
3266	if (bytenr + BTRFS_SUPER_INFO_SIZE >= i_size_read(bdev->bd_inode))
3267		return -EINVAL;
3268
3269	bh = __bread(bdev, bytenr / 4096, BTRFS_SUPER_INFO_SIZE);
3270	/*
3271	 * If we fail to read from the underlying devices, as of now
3272	 * the best option we have is to mark it EIO.
3273	 */
3274	if (!bh)
3275		return -EIO;
3276
3277	super = (struct btrfs_super_block *)bh->b_data;
3278	if (btrfs_super_bytenr(super) != bytenr ||
3279		    btrfs_super_magic(super) != BTRFS_MAGIC) {
3280		brelse(bh);
3281		return -EINVAL;
3282	}
3283
3284	*bh_ret = bh;
3285	return 0;
3286}
3287
3288
3289struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
3290{
3291	struct buffer_head *bh;
3292	struct buffer_head *latest = NULL;
3293	struct btrfs_super_block *super;
3294	int i;
3295	u64 transid = 0;
3296	int ret = -EINVAL;
3297
3298	/* we would like to check all the supers, but that would make
3299	 * a btrfs mount succeed after a mkfs from a different FS.
3300	 * So, we need to add a special mount option to scan for
3301	 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
3302	 */
3303	for (i = 0; i < 1; i++) {
3304		ret = btrfs_read_dev_one_super(bdev, i, &bh);
3305		if (ret)
3306			continue;
3307
3308		super = (struct btrfs_super_block *)bh->b_data;
3309
3310		if (!latest || btrfs_super_generation(super) > transid) {
3311			brelse(latest);
3312			latest = bh;
3313			transid = btrfs_super_generation(super);
3314		} else {
3315			brelse(bh);
3316		}
3317	}
3318
3319	if (!latest)
3320		return ERR_PTR(ret);
3321
3322	return latest;
3323}
3324
3325/*
3326 * this should be called twice, once with wait == 0 and
3327 * once with wait == 1.  When wait == 0 is done, all the buffer heads
3328 * we write are pinned.
3329 *
3330 * They are released when wait == 1 is done.
3331 * max_mirrors must be the same for both runs, and it indicates how
3332 * many supers on this one device should be written.
3333 *
3334 * max_mirrors == 0 means to write them all.
3335 */
3336static int write_dev_supers(struct btrfs_device *device,
3337			    struct btrfs_super_block *sb,
3338			    int do_barriers, int wait, int max_mirrors)
3339{
 
 
3340	struct buffer_head *bh;
3341	int i;
3342	int ret;
3343	int errors = 0;
3344	u32 crc;
3345	u64 bytenr;
 
3346
3347	if (max_mirrors == 0)
3348		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
3349
 
 
3350	for (i = 0; i < max_mirrors; i++) {
3351		bytenr = btrfs_sb_offset(i);
3352		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
3353		    device->commit_total_bytes)
3354			break;
3355
3356		if (wait) {
3357			bh = __find_get_block(device->bdev, bytenr / 4096,
3358					      BTRFS_SUPER_INFO_SIZE);
3359			if (!bh) {
3360				errors++;
3361				continue;
3362			}
3363			wait_on_buffer(bh);
3364			if (!buffer_uptodate(bh))
3365				errors++;
3366
3367			/* drop our reference */
3368			brelse(bh);
3369
3370			/* drop the reference from the wait == 0 run */
3371			brelse(bh);
 
 
 
 
 
 
 
 
3372			continue;
3373		} else {
3374			btrfs_set_super_bytenr(sb, bytenr);
3375
3376			crc = ~(u32)0;
3377			crc = btrfs_csum_data((char *)sb +
3378					      BTRFS_CSUM_SIZE, crc,
3379					      BTRFS_SUPER_INFO_SIZE -
3380					      BTRFS_CSUM_SIZE);
3381			btrfs_csum_final(crc, sb->csum);
3382
3383			/*
3384			 * one reference for us, and we leave it for the
3385			 * caller
3386			 */
3387			bh = __getblk(device->bdev, bytenr / 4096,
3388				      BTRFS_SUPER_INFO_SIZE);
3389			if (!bh) {
3390				btrfs_err(device->dev_root->fs_info,
3391				    "couldn't get super buffer head for bytenr %llu",
3392				    bytenr);
3393				errors++;
3394				continue;
3395			}
3396
3397			memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
3398
3399			/* one reference for submit_bh */
3400			get_bh(bh);
3401
3402			set_buffer_uptodate(bh);
3403			lock_buffer(bh);
3404			bh->b_end_io = btrfs_end_buffer_write_sync;
3405			bh->b_private = device;
3406		}
3407
3408		/*
3409		 * we fua the first super.  The others we allow
3410		 * to go down lazy.
3411		 */
3412		if (i == 0)
3413			ret = btrfsic_submit_bh(WRITE_FUA, bh);
3414		else
3415			ret = btrfsic_submit_bh(WRITE_SYNC, bh);
3416		if (ret)
3417			errors++;
3418	}
3419	return errors < i ? 0 : -1;
3420}
3421
3422/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3423 * endio for the write_dev_flush, this will wake anyone waiting
3424 * for the barrier when it is done
3425 */
3426static void btrfs_end_empty_barrier(struct bio *bio)
3427{
3428	if (bio->bi_private)
3429		complete(bio->bi_private);
3430	bio_put(bio);
3431}
3432
3433/*
3434 * trigger flushes for one the devices.  If you pass wait == 0, the flushes are
3435 * sent down.  With wait == 1, it waits for the previous flush.
3436 *
3437 * any device where the flush fails with eopnotsupp are flagged as not-barrier
3438 * capable
3439 */
3440static int write_dev_flush(struct btrfs_device *device, int wait)
3441{
3442	struct bio *bio;
3443	int ret = 0;
3444
3445	if (device->nobarriers)
3446		return 0;
3447
3448	if (wait) {
3449		bio = device->flush_bio;
3450		if (!bio)
3451			return 0;
 
 
3452
3453		wait_for_completion(&device->flush_wait);
 
 
3454
3455		if (bio->bi_error) {
3456			ret = bio->bi_error;
3457			btrfs_dev_stat_inc_and_print(device,
3458				BTRFS_DEV_STAT_FLUSH_ERRS);
3459		}
 
3460
3461		/* drop the reference from the wait == 0 run */
3462		bio_put(bio);
3463		device->flush_bio = NULL;
3464
3465		return ret;
3466	}
3467
3468	/*
3469	 * one reference for us, and we leave it for the
3470	 * caller
3471	 */
3472	device->flush_bio = NULL;
3473	bio = btrfs_io_bio_alloc(GFP_NOFS, 0);
3474	if (!bio)
3475		return -ENOMEM;
3476
3477	bio->bi_end_io = btrfs_end_empty_barrier;
3478	bio->bi_bdev = device->bdev;
3479	init_completion(&device->flush_wait);
3480	bio->bi_private = &device->flush_wait;
3481	device->flush_bio = bio;
3482
3483	bio_get(bio);
3484	btrfsic_submit_bio(WRITE_FLUSH, bio);
3485
 
 
 
 
3486	return 0;
3487}
3488
3489/*
3490 * send an empty flush down to each device in parallel,
3491 * then wait for them
3492 */
3493static int barrier_all_devices(struct btrfs_fs_info *info)
3494{
3495	struct list_head *head;
3496	struct btrfs_device *dev;
3497	int errors_send = 0;
3498	int errors_wait = 0;
3499	int ret;
3500
 
3501	/* send down all the barriers */
3502	head = &info->fs_devices->devices;
3503	list_for_each_entry_rcu(dev, head, dev_list) {
3504		if (dev->missing)
3505			continue;
3506		if (!dev->bdev) {
3507			errors_send++;
3508			continue;
3509		}
3510		if (!dev->in_fs_metadata || !dev->writeable)
3511			continue;
3512
3513		ret = write_dev_flush(dev, 0);
3514		if (ret)
3515			errors_send++;
3516	}
3517
3518	/* wait for all the barriers */
3519	list_for_each_entry_rcu(dev, head, dev_list) {
3520		if (dev->missing)
3521			continue;
3522		if (!dev->bdev) {
3523			errors_wait++;
3524			continue;
3525		}
3526		if (!dev->in_fs_metadata || !dev->writeable)
 
3527			continue;
3528
3529		ret = write_dev_flush(dev, 1);
3530		if (ret)
 
 
 
3531			errors_wait++;
 
 
 
 
 
 
 
 
 
 
3532	}
3533	if (errors_send > info->num_tolerated_disk_barrier_failures ||
3534	    errors_wait > info->num_tolerated_disk_barrier_failures)
3535		return -EIO;
3536	return 0;
3537}
3538
3539int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags)
3540{
3541	int raid_type;
3542	int min_tolerated = INT_MAX;
3543
3544	if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 ||
3545	    (flags & BTRFS_AVAIL_ALLOC_BIT_SINGLE))
3546		min_tolerated = min(min_tolerated,
3547				    btrfs_raid_array[BTRFS_RAID_SINGLE].
3548				    tolerated_failures);
3549
3550	for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
3551		if (raid_type == BTRFS_RAID_SINGLE)
3552			continue;
3553		if (!(flags & btrfs_raid_group[raid_type]))
3554			continue;
3555		min_tolerated = min(min_tolerated,
3556				    btrfs_raid_array[raid_type].
3557				    tolerated_failures);
3558	}
3559
3560	if (min_tolerated == INT_MAX) {
3561		pr_warn("BTRFS: unknown raid flag: %llu\n", flags);
3562		min_tolerated = 0;
3563	}
3564
3565	return min_tolerated;
3566}
3567
3568int btrfs_calc_num_tolerated_disk_barrier_failures(
3569	struct btrfs_fs_info *fs_info)
3570{
3571	struct btrfs_ioctl_space_info space;
3572	struct btrfs_space_info *sinfo;
3573	u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
3574		       BTRFS_BLOCK_GROUP_SYSTEM,
3575		       BTRFS_BLOCK_GROUP_METADATA,
3576		       BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
3577	int i;
3578	int c;
3579	int num_tolerated_disk_barrier_failures =
3580		(int)fs_info->fs_devices->num_devices;
3581
3582	for (i = 0; i < ARRAY_SIZE(types); i++) {
3583		struct btrfs_space_info *tmp;
3584
3585		sinfo = NULL;
3586		rcu_read_lock();
3587		list_for_each_entry_rcu(tmp, &fs_info->space_info, list) {
3588			if (tmp->flags == types[i]) {
3589				sinfo = tmp;
3590				break;
3591			}
3592		}
3593		rcu_read_unlock();
3594
3595		if (!sinfo)
3596			continue;
3597
3598		down_read(&sinfo->groups_sem);
3599		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3600			u64 flags;
3601
3602			if (list_empty(&sinfo->block_groups[c]))
3603				continue;
3604
3605			btrfs_get_block_group_info(&sinfo->block_groups[c],
3606						   &space);
3607			if (space.total_bytes == 0 || space.used_bytes == 0)
3608				continue;
3609			flags = space.flags;
3610
3611			num_tolerated_disk_barrier_failures = min(
3612				num_tolerated_disk_barrier_failures,
3613				btrfs_get_num_tolerated_disk_barrier_failures(
3614					flags));
3615		}
3616		up_read(&sinfo->groups_sem);
3617	}
3618
3619	return num_tolerated_disk_barrier_failures;
3620}
3621
3622static int write_all_supers(struct btrfs_root *root, int max_mirrors)
3623{
3624	struct list_head *head;
3625	struct btrfs_device *dev;
3626	struct btrfs_super_block *sb;
3627	struct btrfs_dev_item *dev_item;
3628	int ret;
3629	int do_barriers;
3630	int max_errors;
3631	int total_errors = 0;
3632	u64 flags;
3633
3634	do_barriers = !btrfs_test_opt(root, NOBARRIER);
3635	backup_super_roots(root->fs_info);
 
 
 
 
 
 
 
3636
3637	sb = root->fs_info->super_for_commit;
3638	dev_item = &sb->dev_item;
3639
3640	mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
3641	head = &root->fs_info->fs_devices->devices;
3642	max_errors = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
3643
3644	if (do_barriers) {
3645		ret = barrier_all_devices(root->fs_info);
3646		if (ret) {
3647			mutex_unlock(
3648				&root->fs_info->fs_devices->device_list_mutex);
3649			btrfs_std_error(root->fs_info, ret,
3650				    "errors while submitting device barriers.");
3651			return ret;
3652		}
3653	}
3654
3655	list_for_each_entry_rcu(dev, head, dev_list) {
3656		if (!dev->bdev) {
3657			total_errors++;
3658			continue;
3659		}
3660		if (!dev->in_fs_metadata || !dev->writeable)
 
3661			continue;
3662
3663		btrfs_set_stack_device_generation(dev_item, 0);
3664		btrfs_set_stack_device_type(dev_item, dev->type);
3665		btrfs_set_stack_device_id(dev_item, dev->devid);
3666		btrfs_set_stack_device_total_bytes(dev_item,
3667						   dev->commit_total_bytes);
3668		btrfs_set_stack_device_bytes_used(dev_item,
3669						  dev->commit_bytes_used);
3670		btrfs_set_stack_device_io_align(dev_item, dev->io_align);
3671		btrfs_set_stack_device_io_width(dev_item, dev->io_width);
3672		btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
3673		memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
3674		memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
 
3675
3676		flags = btrfs_super_flags(sb);
3677		btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
3678
3679		ret = write_dev_supers(dev, sb, do_barriers, 0, max_mirrors);
 
 
 
 
 
 
 
 
3680		if (ret)
3681			total_errors++;
3682	}
3683	if (total_errors > max_errors) {
3684		btrfs_err(root->fs_info, "%d errors while writing supers",
3685		       total_errors);
3686		mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
3687
3688		/* FUA is masked off if unsupported and can't be the reason */
3689		btrfs_std_error(root->fs_info, -EIO,
3690			    "%d errors while writing supers", total_errors);
 
3691		return -EIO;
3692	}
3693
3694	total_errors = 0;
3695	list_for_each_entry_rcu(dev, head, dev_list) {
3696		if (!dev->bdev)
3697			continue;
3698		if (!dev->in_fs_metadata || !dev->writeable)
 
3699			continue;
3700
3701		ret = write_dev_supers(dev, sb, do_barriers, 1, max_mirrors);
3702		if (ret)
3703			total_errors++;
3704	}
3705	mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
3706	if (total_errors > max_errors) {
3707		btrfs_std_error(root->fs_info, -EIO,
3708			    "%d errors while writing supers", total_errors);
 
3709		return -EIO;
3710	}
3711	return 0;
3712}
3713
3714int write_ctree_super(struct btrfs_trans_handle *trans,
3715		      struct btrfs_root *root, int max_mirrors)
3716{
3717	return write_all_supers(root, max_mirrors);
3718}
3719
3720/* Drop a fs root from the radix tree and free it. */
3721void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
3722				  struct btrfs_root *root)
3723{
3724	spin_lock(&fs_info->fs_roots_radix_lock);
3725	radix_tree_delete(&fs_info->fs_roots_radix,
3726			  (unsigned long)root->root_key.objectid);
3727	spin_unlock(&fs_info->fs_roots_radix_lock);
3728
3729	if (btrfs_root_refs(&root->root_item) == 0)
3730		synchronize_srcu(&fs_info->subvol_srcu);
3731
3732	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
3733		btrfs_free_log(NULL, root);
 
 
 
 
 
 
 
3734
3735	if (root->free_ino_pinned)
3736		__btrfs_remove_free_space_cache(root->free_ino_pinned);
3737	if (root->free_ino_ctl)
3738		__btrfs_remove_free_space_cache(root->free_ino_ctl);
3739	free_fs_root(root);
3740}
3741
3742static void free_fs_root(struct btrfs_root *root)
3743{
3744	iput(root->ino_cache_inode);
3745	WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
3746	btrfs_free_block_rsv(root, root->orphan_block_rsv);
3747	root->orphan_block_rsv = NULL;
3748	if (root->anon_dev)
3749		free_anon_bdev(root->anon_dev);
3750	if (root->subv_writers)
3751		btrfs_free_subvolume_writers(root->subv_writers);
3752	free_extent_buffer(root->node);
3753	free_extent_buffer(root->commit_root);
3754	kfree(root->free_ino_ctl);
3755	kfree(root->free_ino_pinned);
3756	kfree(root->name);
3757	btrfs_put_fs_root(root);
3758}
3759
3760void btrfs_free_fs_root(struct btrfs_root *root)
3761{
3762	free_fs_root(root);
3763}
3764
3765int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
3766{
3767	u64 root_objectid = 0;
3768	struct btrfs_root *gang[8];
3769	int i = 0;
3770	int err = 0;
3771	unsigned int ret = 0;
3772	int index;
3773
3774	while (1) {
3775		index = srcu_read_lock(&fs_info->subvol_srcu);
3776		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
3777					     (void **)gang, root_objectid,
3778					     ARRAY_SIZE(gang));
3779		if (!ret) {
3780			srcu_read_unlock(&fs_info->subvol_srcu, index);
3781			break;
3782		}
3783		root_objectid = gang[ret - 1]->root_key.objectid + 1;
3784
3785		for (i = 0; i < ret; i++) {
3786			/* Avoid to grab roots in dead_roots */
3787			if (btrfs_root_refs(&gang[i]->root_item) == 0) {
3788				gang[i] = NULL;
3789				continue;
3790			}
3791			/* grab all the search result for later use */
3792			gang[i] = btrfs_grab_fs_root(gang[i]);
3793		}
3794		srcu_read_unlock(&fs_info->subvol_srcu, index);
3795
3796		for (i = 0; i < ret; i++) {
3797			if (!gang[i])
3798				continue;
3799			root_objectid = gang[i]->root_key.objectid;
3800			err = btrfs_orphan_cleanup(gang[i]);
3801			if (err)
3802				break;
3803			btrfs_put_fs_root(gang[i]);
3804		}
3805		root_objectid++;
3806	}
3807
3808	/* release the uncleaned roots due to error */
3809	for (; i < ret; i++) {
3810		if (gang[i])
3811			btrfs_put_fs_root(gang[i]);
3812	}
3813	return err;
3814}
3815
3816int btrfs_commit_super(struct btrfs_root *root)
3817{
 
3818	struct btrfs_trans_handle *trans;
3819
3820	mutex_lock(&root->fs_info->cleaner_mutex);
3821	btrfs_run_delayed_iputs(root);
3822	mutex_unlock(&root->fs_info->cleaner_mutex);
3823	wake_up_process(root->fs_info->cleaner_kthread);
3824
3825	/* wait until ongoing cleanup work done */
3826	down_write(&root->fs_info->cleanup_work_sem);
3827	up_write(&root->fs_info->cleanup_work_sem);
3828
3829	trans = btrfs_join_transaction(root);
3830	if (IS_ERR(trans))
3831		return PTR_ERR(trans);
3832	return btrfs_commit_transaction(trans, root);
3833}
3834
3835void close_ctree(struct btrfs_root *root)
3836{
3837	struct btrfs_fs_info *fs_info = root->fs_info;
3838	int ret;
3839
3840	fs_info->closing = 1;
3841	smp_mb();
 
 
 
 
 
 
3842
3843	/* wait for the qgroup rescan worker to stop */
3844	btrfs_qgroup_wait_for_completion(fs_info);
3845
3846	/* wait for the uuid_scan task to finish */
3847	down(&fs_info->uuid_tree_rescan_sem);
3848	/* avoid complains from lockdep et al., set sem back to initial state */
3849	up(&fs_info->uuid_tree_rescan_sem);
3850
3851	/* pause restriper - we want to resume on mount */
3852	btrfs_pause_balance(fs_info);
3853
3854	btrfs_dev_replace_suspend_for_unmount(fs_info);
3855
3856	btrfs_scrub_cancel(fs_info);
3857
3858	/* wait for any defraggers to finish */
3859	wait_event(fs_info->transaction_wait,
3860		   (atomic_read(&fs_info->defrag_running) == 0));
3861
3862	/* clear out the rbtree of defraggable inodes */
3863	btrfs_cleanup_defrag_inodes(fs_info);
3864
3865	cancel_work_sync(&fs_info->async_reclaim_work);
3866
3867	if (!(fs_info->sb->s_flags & MS_RDONLY)) {
3868		/*
3869		 * If the cleaner thread is stopped and there are
3870		 * block groups queued for removal, the deletion will be
3871		 * skipped when we quit the cleaner thread.
3872		 */
3873		btrfs_delete_unused_bgs(root->fs_info);
3874
3875		ret = btrfs_commit_super(root);
3876		if (ret)
3877			btrfs_err(fs_info, "commit super ret %d", ret);
3878	}
3879
3880	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
3881		btrfs_error_commit_super(root);
 
3882
3883	kthread_stop(fs_info->transaction_kthread);
3884	kthread_stop(fs_info->cleaner_kthread);
3885
3886	fs_info->closing = 2;
3887	smp_mb();
3888
3889	btrfs_free_qgroup_config(fs_info);
 
3890
3891	if (percpu_counter_sum(&fs_info->delalloc_bytes)) {
3892		btrfs_info(fs_info, "at unmount delalloc count %lld",
3893		       percpu_counter_sum(&fs_info->delalloc_bytes));
3894	}
3895
 
 
 
 
3896	btrfs_sysfs_remove_mounted(fs_info);
3897	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
3898
3899	btrfs_free_fs_roots(fs_info);
3900
3901	btrfs_put_block_group_cache(fs_info);
3902
3903	btrfs_free_block_groups(fs_info);
3904
3905	/*
3906	 * we must make sure there is not any read request to
3907	 * submit after we stopping all workers.
3908	 */
3909	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
3910	btrfs_stop_all_workers(fs_info);
3911
3912	fs_info->open = 0;
 
 
3913	free_root_pointers(fs_info, 1);
3914
3915	iput(fs_info->btree_inode);
3916
3917#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3918	if (btrfs_test_opt(root, CHECK_INTEGRITY))
3919		btrfsic_unmount(root, fs_info->fs_devices);
3920#endif
3921
 
3922	btrfs_close_devices(fs_info->fs_devices);
3923	btrfs_mapping_tree_free(&fs_info->mapping_tree);
3924
3925	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
3926	percpu_counter_destroy(&fs_info->delalloc_bytes);
3927	percpu_counter_destroy(&fs_info->bio_counter);
3928	bdi_destroy(&fs_info->bdi);
3929	cleanup_srcu_struct(&fs_info->subvol_srcu);
3930
 
3931	btrfs_free_stripe_hash_table(fs_info);
3932
3933	__btrfs_free_block_rsv(root->orphan_block_rsv);
3934	root->orphan_block_rsv = NULL;
3935
3936	lock_chunks(root);
3937	while (!list_empty(&fs_info->pinned_chunks)) {
3938		struct extent_map *em;
3939
3940		em = list_first_entry(&fs_info->pinned_chunks,
3941				      struct extent_map, list);
3942		list_del_init(&em->list);
3943		free_extent_map(em);
3944	}
3945	unlock_chunks(root);
3946}
3947
3948int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
3949			  int atomic)
3950{
3951	int ret;
3952	struct inode *btree_inode = buf->pages[0]->mapping->host;
3953
3954	ret = extent_buffer_uptodate(buf);
3955	if (!ret)
3956		return ret;
3957
3958	ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
3959				    parent_transid, atomic);
3960	if (ret == -EAGAIN)
3961		return ret;
3962	return !ret;
3963}
3964
3965void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
3966{
 
3967	struct btrfs_root *root;
3968	u64 transid = btrfs_header_generation(buf);
3969	int was_dirty;
3970
3971#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
3972	/*
3973	 * This is a fast path so only do this check if we have sanity tests
3974	 * enabled.  Normal people shouldn't be marking dummy buffers as dirty
3975	 * outside of the sanity tests.
3976	 */
3977	if (unlikely(test_bit(EXTENT_BUFFER_DUMMY, &buf->bflags)))
3978		return;
3979#endif
3980	root = BTRFS_I(buf->pages[0]->mapping->host)->root;
 
3981	btrfs_assert_tree_locked(buf);
3982	if (transid != root->fs_info->generation)
3983		WARN(1, KERN_CRIT "btrfs transid mismatch buffer %llu, "
3984		       "found %llu running %llu\n",
3985			buf->start, transid, root->fs_info->generation);
3986	was_dirty = set_extent_buffer_dirty(buf);
3987	if (!was_dirty)
3988		__percpu_counter_add(&root->fs_info->dirty_metadata_bytes,
3989				     buf->len,
3990				     root->fs_info->dirty_metadata_batch);
3991#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3992	if (btrfs_header_level(buf) == 0 && check_leaf(root, buf)) {
3993		btrfs_print_leaf(root, buf);
 
 
 
 
 
 
3994		ASSERT(0);
3995	}
3996#endif
3997}
3998
3999static void __btrfs_btree_balance_dirty(struct btrfs_root *root,
4000					int flush_delayed)
4001{
4002	/*
4003	 * looks as though older kernels can get into trouble with
4004	 * this code, they end up stuck in balance_dirty_pages forever
4005	 */
4006	int ret;
4007
4008	if (current->flags & PF_MEMALLOC)
4009		return;
4010
4011	if (flush_delayed)
4012		btrfs_balance_delayed_items(root);
4013
4014	ret = percpu_counter_compare(&root->fs_info->dirty_metadata_bytes,
4015				     BTRFS_DIRTY_METADATA_THRESH);
 
4016	if (ret > 0) {
4017		balance_dirty_pages_ratelimited(
4018				   root->fs_info->btree_inode->i_mapping);
4019	}
4020}
4021
4022void btrfs_btree_balance_dirty(struct btrfs_root *root)
4023{
4024	__btrfs_btree_balance_dirty(root, 1);
4025}
4026
4027void btrfs_btree_balance_dirty_nodelay(struct btrfs_root *root)
4028{
4029	__btrfs_btree_balance_dirty(root, 0);
4030}
4031
4032int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
 
4033{
4034	struct btrfs_root *root = BTRFS_I(buf->pages[0]->mapping->host)->root;
4035	return btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
4036}
4037
4038static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
4039			      int read_only)
4040{
4041	struct btrfs_super_block *sb = fs_info->super_copy;
4042	u64 nodesize = btrfs_super_nodesize(sb);
4043	u64 sectorsize = btrfs_super_sectorsize(sb);
4044	int ret = 0;
4045
4046	if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
4047		printk(KERN_ERR "BTRFS: no valid FS found\n");
4048		ret = -EINVAL;
4049	}
4050	if (btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP)
4051		printk(KERN_WARNING "BTRFS: unrecognized super flag: %llu\n",
4052				btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);
4053	if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
4054		printk(KERN_ERR "BTRFS: tree_root level too big: %d >= %d\n",
4055				btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
4056		ret = -EINVAL;
4057	}
4058	if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
4059		printk(KERN_ERR "BTRFS: chunk_root level too big: %d >= %d\n",
4060				btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
4061		ret = -EINVAL;
4062	}
4063	if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
4064		printk(KERN_ERR "BTRFS: log_root level too big: %d >= %d\n",
4065				btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
4066		ret = -EINVAL;
4067	}
4068
4069	/*
4070	 * Check sectorsize and nodesize first, other check will need it.
4071	 * Check all possible sectorsize(4K, 8K, 16K, 32K, 64K) here.
4072	 */
4073	if (!is_power_of_2(sectorsize) || sectorsize < 4096 ||
4074	    sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) {
4075		printk(KERN_ERR "BTRFS: invalid sectorsize %llu\n", sectorsize);
4076		ret = -EINVAL;
4077	}
4078	/* Only PAGE SIZE is supported yet */
4079	if (sectorsize != PAGE_SIZE) {
4080		printk(KERN_ERR "BTRFS: sectorsize %llu not supported yet, only support %lu\n",
4081				sectorsize, PAGE_SIZE);
4082		ret = -EINVAL;
4083	}
4084	if (!is_power_of_2(nodesize) || nodesize < sectorsize ||
4085	    nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
4086		printk(KERN_ERR "BTRFS: invalid nodesize %llu\n", nodesize);
4087		ret = -EINVAL;
4088	}
4089	if (nodesize != le32_to_cpu(sb->__unused_leafsize)) {
4090		printk(KERN_ERR "BTRFS: invalid leafsize %u, should be %llu\n",
4091				le32_to_cpu(sb->__unused_leafsize),
4092				nodesize);
4093		ret = -EINVAL;
4094	}
4095
4096	/* Root alignment check */
4097	if (!IS_ALIGNED(btrfs_super_root(sb), sectorsize)) {
4098		printk(KERN_WARNING "BTRFS: tree_root block unaligned: %llu\n",
4099				btrfs_super_root(sb));
4100		ret = -EINVAL;
4101	}
4102	if (!IS_ALIGNED(btrfs_super_chunk_root(sb), sectorsize)) {
4103		printk(KERN_WARNING "BTRFS: chunk_root block unaligned: %llu\n",
4104				btrfs_super_chunk_root(sb));
4105		ret = -EINVAL;
4106	}
4107	if (!IS_ALIGNED(btrfs_super_log_root(sb), sectorsize)) {
4108		printk(KERN_WARNING "BTRFS: log_root block unaligned: %llu\n",
4109				btrfs_super_log_root(sb));
4110		ret = -EINVAL;
4111	}
4112
4113	if (memcmp(fs_info->fsid, sb->dev_item.fsid, BTRFS_UUID_SIZE) != 0) {
4114		printk(KERN_ERR "BTRFS: dev_item UUID does not match fsid: %pU != %pU\n",
4115				fs_info->fsid, sb->dev_item.fsid);
4116		ret = -EINVAL;
4117	}
4118
4119	/*
4120	 * Hint to catch really bogus numbers, bitflips or so, more exact checks are
4121	 * done later
4122	 */
4123	if (btrfs_super_num_devices(sb) > (1UL << 31))
4124		printk(KERN_WARNING "BTRFS: suspicious number of devices: %llu\n",
4125				btrfs_super_num_devices(sb));
4126	if (btrfs_super_num_devices(sb) == 0) {
4127		printk(KERN_ERR "BTRFS: number of devices is 0\n");
4128		ret = -EINVAL;
4129	}
4130
4131	if (btrfs_super_bytenr(sb) != BTRFS_SUPER_INFO_OFFSET) {
4132		printk(KERN_ERR "BTRFS: super offset mismatch %llu != %u\n",
4133				btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET);
4134		ret = -EINVAL;
4135	}
4136
4137	/*
4138	 * Obvious sys_chunk_array corruptions, it must hold at least one key
4139	 * and one chunk
4140	 */
4141	if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
4142		printk(KERN_ERR "BTRFS: system chunk array too big %u > %u\n",
4143				btrfs_super_sys_array_size(sb),
4144				BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
4145		ret = -EINVAL;
4146	}
4147	if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
4148			+ sizeof(struct btrfs_chunk)) {
4149		printk(KERN_ERR "BTRFS: system chunk array too small %u < %zu\n",
4150				btrfs_super_sys_array_size(sb),
4151				sizeof(struct btrfs_disk_key)
4152				+ sizeof(struct btrfs_chunk));
4153		ret = -EINVAL;
4154	}
4155
4156	/*
4157	 * The generation is a global counter, we'll trust it more than the others
4158	 * but it's still possible that it's the one that's wrong.
4159	 */
4160	if (btrfs_super_generation(sb) < btrfs_super_chunk_root_generation(sb))
4161		printk(KERN_WARNING
4162			"BTRFS: suspicious: generation < chunk_root_generation: %llu < %llu\n",
4163			btrfs_super_generation(sb), btrfs_super_chunk_root_generation(sb));
4164	if (btrfs_super_generation(sb) < btrfs_super_cache_generation(sb)
4165	    && btrfs_super_cache_generation(sb) != (u64)-1)
4166		printk(KERN_WARNING
4167			"BTRFS: suspicious: generation < cache_generation: %llu < %llu\n",
4168			btrfs_super_generation(sb), btrfs_super_cache_generation(sb));
4169
4170	return ret;
4171}
4172
4173static void btrfs_error_commit_super(struct btrfs_root *root)
4174{
4175	mutex_lock(&root->fs_info->cleaner_mutex);
4176	btrfs_run_delayed_iputs(root);
4177	mutex_unlock(&root->fs_info->cleaner_mutex);
4178
4179	down_write(&root->fs_info->cleanup_work_sem);
4180	up_write(&root->fs_info->cleanup_work_sem);
4181
4182	/* cleanup FS via transaction */
4183	btrfs_cleanup_transaction(root);
4184}
4185
4186static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
4187{
4188	struct btrfs_ordered_extent *ordered;
4189
4190	spin_lock(&root->ordered_extent_lock);
4191	/*
4192	 * This will just short circuit the ordered completion stuff which will
4193	 * make sure the ordered extent gets properly cleaned up.
4194	 */
4195	list_for_each_entry(ordered, &root->ordered_extents,
4196			    root_extent_list)
4197		set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
4198	spin_unlock(&root->ordered_extent_lock);
4199}
4200
4201static void btrfs_destroy_all_ordered_extents(struct btrfs_fs_info *fs_info)
4202{
4203	struct btrfs_root *root;
4204	struct list_head splice;
4205
4206	INIT_LIST_HEAD(&splice);
4207
4208	spin_lock(&fs_info->ordered_root_lock);
4209	list_splice_init(&fs_info->ordered_roots, &splice);
4210	while (!list_empty(&splice)) {
4211		root = list_first_entry(&splice, struct btrfs_root,
4212					ordered_root);
4213		list_move_tail(&root->ordered_root,
4214			       &fs_info->ordered_roots);
4215
4216		spin_unlock(&fs_info->ordered_root_lock);
4217		btrfs_destroy_ordered_extents(root);
4218
4219		cond_resched();
4220		spin_lock(&fs_info->ordered_root_lock);
4221	}
4222	spin_unlock(&fs_info->ordered_root_lock);
 
 
 
 
 
 
 
 
4223}
4224
4225static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
4226				      struct btrfs_root *root)
4227{
4228	struct rb_node *node;
4229	struct btrfs_delayed_ref_root *delayed_refs;
4230	struct btrfs_delayed_ref_node *ref;
4231	int ret = 0;
4232
4233	delayed_refs = &trans->delayed_refs;
4234
4235	spin_lock(&delayed_refs->lock);
4236	if (atomic_read(&delayed_refs->num_entries) == 0) {
4237		spin_unlock(&delayed_refs->lock);
4238		btrfs_info(root->fs_info, "delayed_refs has NO entry");
4239		return ret;
4240	}
4241
4242	while ((node = rb_first(&delayed_refs->href_root)) != NULL) {
4243		struct btrfs_delayed_ref_head *head;
4244		struct btrfs_delayed_ref_node *tmp;
4245		bool pin_bytes = false;
4246
4247		head = rb_entry(node, struct btrfs_delayed_ref_head,
4248				href_node);
4249		if (!mutex_trylock(&head->mutex)) {
4250			atomic_inc(&head->node.refs);
4251			spin_unlock(&delayed_refs->lock);
4252
4253			mutex_lock(&head->mutex);
4254			mutex_unlock(&head->mutex);
4255			btrfs_put_delayed_ref(&head->node);
4256			spin_lock(&delayed_refs->lock);
4257			continue;
4258		}
4259		spin_lock(&head->lock);
4260		list_for_each_entry_safe_reverse(ref, tmp, &head->ref_list,
4261						 list) {
 
4262			ref->in_tree = 0;
4263			list_del(&ref->list);
 
 
 
4264			atomic_dec(&delayed_refs->num_entries);
4265			btrfs_put_delayed_ref(ref);
4266		}
4267		if (head->must_insert_reserved)
4268			pin_bytes = true;
4269		btrfs_free_delayed_extent_op(head->extent_op);
4270		delayed_refs->num_heads--;
4271		if (head->processing == 0)
4272			delayed_refs->num_heads_ready--;
4273		atomic_dec(&delayed_refs->num_entries);
4274		head->node.in_tree = 0;
4275		rb_erase(&head->href_node, &delayed_refs->href_root);
4276		spin_unlock(&head->lock);
4277		spin_unlock(&delayed_refs->lock);
4278		mutex_unlock(&head->mutex);
4279
4280		if (pin_bytes)
4281			btrfs_pin_extent(root, head->node.bytenr,
4282					 head->node.num_bytes, 1);
4283		btrfs_put_delayed_ref(&head->node);
 
4284		cond_resched();
4285		spin_lock(&delayed_refs->lock);
4286	}
4287
4288	spin_unlock(&delayed_refs->lock);
4289
4290	return ret;
4291}
4292
4293static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
4294{
4295	struct btrfs_inode *btrfs_inode;
4296	struct list_head splice;
4297
4298	INIT_LIST_HEAD(&splice);
4299
4300	spin_lock(&root->delalloc_lock);
4301	list_splice_init(&root->delalloc_inodes, &splice);
4302
4303	while (!list_empty(&splice)) {
 
4304		btrfs_inode = list_first_entry(&splice, struct btrfs_inode,
4305					       delalloc_inodes);
4306
4307		list_del_init(&btrfs_inode->delalloc_inodes);
4308		clear_bit(BTRFS_INODE_IN_DELALLOC_LIST,
4309			  &btrfs_inode->runtime_flags);
4310		spin_unlock(&root->delalloc_lock);
4311
4312		btrfs_invalidate_inodes(btrfs_inode->root);
4313
 
 
 
 
 
 
 
4314		spin_lock(&root->delalloc_lock);
4315	}
4316
4317	spin_unlock(&root->delalloc_lock);
4318}
4319
4320static void btrfs_destroy_all_delalloc_inodes(struct btrfs_fs_info *fs_info)
4321{
4322	struct btrfs_root *root;
4323	struct list_head splice;
4324
4325	INIT_LIST_HEAD(&splice);
4326
4327	spin_lock(&fs_info->delalloc_root_lock);
4328	list_splice_init(&fs_info->delalloc_roots, &splice);
4329	while (!list_empty(&splice)) {
4330		root = list_first_entry(&splice, struct btrfs_root,
4331					 delalloc_root);
4332		list_del_init(&root->delalloc_root);
4333		root = btrfs_grab_fs_root(root);
4334		BUG_ON(!root);
4335		spin_unlock(&fs_info->delalloc_root_lock);
4336
4337		btrfs_destroy_delalloc_inodes(root);
4338		btrfs_put_fs_root(root);
4339
4340		spin_lock(&fs_info->delalloc_root_lock);
4341	}
4342	spin_unlock(&fs_info->delalloc_root_lock);
4343}
4344
4345static int btrfs_destroy_marked_extents(struct btrfs_root *root,
4346					struct extent_io_tree *dirty_pages,
4347					int mark)
4348{
4349	int ret;
4350	struct extent_buffer *eb;
4351	u64 start = 0;
4352	u64 end;
4353
4354	while (1) {
4355		ret = find_first_extent_bit(dirty_pages, start, &start, &end,
4356					    mark, NULL);
4357		if (ret)
4358			break;
4359
4360		clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS);
4361		while (start <= end) {
4362			eb = btrfs_find_tree_block(root->fs_info, start);
4363			start += root->nodesize;
4364			if (!eb)
4365				continue;
4366			wait_on_extent_buffer_writeback(eb);
4367
4368			if (test_and_clear_bit(EXTENT_BUFFER_DIRTY,
4369					       &eb->bflags))
4370				clear_extent_buffer_dirty(eb);
4371			free_extent_buffer_stale(eb);
4372		}
4373	}
4374
4375	return ret;
4376}
4377
4378static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
4379				       struct extent_io_tree *pinned_extents)
4380{
4381	struct extent_io_tree *unpin;
4382	u64 start;
4383	u64 end;
4384	int ret;
4385	bool loop = true;
4386
4387	unpin = pinned_extents;
4388again:
4389	while (1) {
 
 
 
 
 
 
 
 
 
4390		ret = find_first_extent_bit(unpin, 0, &start, &end,
4391					    EXTENT_DIRTY, NULL);
4392		if (ret)
 
4393			break;
 
4394
4395		clear_extent_dirty(unpin, start, end, GFP_NOFS);
4396		btrfs_error_unpin_extent_range(root, start, end);
 
 
4397		cond_resched();
4398	}
4399
4400	if (loop) {
4401		if (unpin == &root->fs_info->freed_extents[0])
4402			unpin = &root->fs_info->freed_extents[1];
4403		else
4404			unpin = &root->fs_info->freed_extents[0];
4405		loop = false;
4406		goto again;
4407	}
4408
4409	return 0;
4410}
4411
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4412void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
4413				   struct btrfs_root *root)
4414{
4415	btrfs_destroy_delayed_refs(cur_trans, root);
 
 
 
 
 
 
 
 
 
 
 
4416
4417	cur_trans->state = TRANS_STATE_COMMIT_START;
4418	wake_up(&root->fs_info->transaction_blocked_wait);
4419
4420	cur_trans->state = TRANS_STATE_UNBLOCKED;
4421	wake_up(&root->fs_info->transaction_wait);
4422
4423	btrfs_destroy_delayed_inodes(root);
4424	btrfs_assert_delayed_root_empty(root);
4425
4426	btrfs_destroy_marked_extents(root, &cur_trans->dirty_pages,
4427				     EXTENT_DIRTY);
4428	btrfs_destroy_pinned_extent(root,
4429				    root->fs_info->pinned_extents);
4430
4431	cur_trans->state =TRANS_STATE_COMPLETED;
4432	wake_up(&cur_trans->commit_wait);
4433
4434	/*
4435	memset(cur_trans, 0, sizeof(*cur_trans));
4436	kmem_cache_free(btrfs_transaction_cachep, cur_trans);
4437	*/
4438}
4439
4440static int btrfs_cleanup_transaction(struct btrfs_root *root)
4441{
4442	struct btrfs_transaction *t;
4443
4444	mutex_lock(&root->fs_info->transaction_kthread_mutex);
4445
4446	spin_lock(&root->fs_info->trans_lock);
4447	while (!list_empty(&root->fs_info->trans_list)) {
4448		t = list_first_entry(&root->fs_info->trans_list,
4449				     struct btrfs_transaction, list);
4450		if (t->state >= TRANS_STATE_COMMIT_START) {
4451			atomic_inc(&t->use_count);
4452			spin_unlock(&root->fs_info->trans_lock);
4453			btrfs_wait_for_commit(root, t->transid);
4454			btrfs_put_transaction(t);
4455			spin_lock(&root->fs_info->trans_lock);
4456			continue;
4457		}
4458		if (t == root->fs_info->running_transaction) {
4459			t->state = TRANS_STATE_COMMIT_DOING;
4460			spin_unlock(&root->fs_info->trans_lock);
4461			/*
4462			 * We wait for 0 num_writers since we don't hold a trans
4463			 * handle open currently for this transaction.
4464			 */
4465			wait_event(t->writer_wait,
4466				   atomic_read(&t->num_writers) == 0);
4467		} else {
4468			spin_unlock(&root->fs_info->trans_lock);
4469		}
4470		btrfs_cleanup_one_transaction(t, root);
4471
4472		spin_lock(&root->fs_info->trans_lock);
4473		if (t == root->fs_info->running_transaction)
4474			root->fs_info->running_transaction = NULL;
4475		list_del_init(&t->list);
4476		spin_unlock(&root->fs_info->trans_lock);
4477
4478		btrfs_put_transaction(t);
4479		trace_btrfs_transaction_commit(root);
4480		spin_lock(&root->fs_info->trans_lock);
4481	}
4482	spin_unlock(&root->fs_info->trans_lock);
4483	btrfs_destroy_all_ordered_extents(root->fs_info);
4484	btrfs_destroy_delayed_inodes(root);
4485	btrfs_assert_delayed_root_empty(root);
4486	btrfs_destroy_pinned_extent(root, root->fs_info->pinned_extents);
4487	btrfs_destroy_all_delalloc_inodes(root->fs_info);
4488	mutex_unlock(&root->fs_info->transaction_kthread_mutex);
4489
4490	return 0;
4491}
4492
4493static const struct extent_io_ops btree_extent_io_ops = {
 
 
4494	.readpage_end_io_hook = btree_readpage_end_io_hook,
4495	.readpage_io_failed_hook = btree_io_failed_hook,
4496	.submit_bio_hook = btree_submit_bio_hook,
4497	/* note we're sharing with inode.c for the merge bio hook */
4498	.merge_bio_hook = btrfs_merge_bio_hook,
4499};