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v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) 2007 Oracle.  All rights reserved.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   4 */
   5
   6#include <linux/fs.h>
   7#include <linux/blkdev.h>
 
 
   8#include <linux/radix-tree.h>
   9#include <linux/writeback.h>
  10#include <linux/buffer_head.h>
  11#include <linux/workqueue.h>
  12#include <linux/kthread.h>
 
  13#include <linux/slab.h>
  14#include <linux/migrate.h>
  15#include <linux/ratelimit.h>
  16#include <linux/uuid.h>
  17#include <linux/semaphore.h>
  18#include <linux/error-injection.h>
  19#include <linux/crc32c.h>
  20#include <linux/sched/mm.h>
  21#include <asm/unaligned.h>
  22#include <crypto/hash.h>
  23#include "ctree.h"
  24#include "disk-io.h"
 
  25#include "transaction.h"
  26#include "btrfs_inode.h"
  27#include "volumes.h"
  28#include "print-tree.h"
 
  29#include "locking.h"
  30#include "tree-log.h"
  31#include "free-space-cache.h"
  32#include "free-space-tree.h"
  33#include "inode-map.h"
  34#include "check-integrity.h"
  35#include "rcu-string.h"
  36#include "dev-replace.h"
  37#include "raid56.h"
  38#include "sysfs.h"
  39#include "qgroup.h"
  40#include "compression.h"
  41#include "tree-checker.h"
  42#include "ref-verify.h"
  43#include "block-group.h"
  44
  45#define BTRFS_SUPER_FLAG_SUPP	(BTRFS_HEADER_FLAG_WRITTEN |\
  46				 BTRFS_HEADER_FLAG_RELOC |\
  47				 BTRFS_SUPER_FLAG_ERROR |\
  48				 BTRFS_SUPER_FLAG_SEEDING |\
  49				 BTRFS_SUPER_FLAG_METADUMP |\
  50				 BTRFS_SUPER_FLAG_METADUMP_V2)
  51
  52static const struct extent_io_ops btree_extent_io_ops;
 
 
 
 
  53static void end_workqueue_fn(struct btrfs_work *work);
 
 
 
 
 
  54static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
  55static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
  56				      struct btrfs_fs_info *fs_info);
  57static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
  58static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
  59					struct extent_io_tree *dirty_pages,
  60					int mark);
  61static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
  62				       struct extent_io_tree *pinned_extents);
  63static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info);
  64static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info);
  65
  66/*
  67 * btrfs_end_io_wq structs are used to do processing in task context when an IO
  68 * is complete.  This is used during reads to verify checksums, and it is used
  69 * by writes to insert metadata for new file extents after IO is complete.
  70 */
  71struct btrfs_end_io_wq {
  72	struct bio *bio;
  73	bio_end_io_t *end_io;
  74	void *private;
  75	struct btrfs_fs_info *info;
  76	blk_status_t status;
  77	enum btrfs_wq_endio_type metadata;
 
  78	struct btrfs_work work;
  79};
  80
  81static struct kmem_cache *btrfs_end_io_wq_cache;
  82
  83int __init btrfs_end_io_wq_init(void)
  84{
  85	btrfs_end_io_wq_cache = kmem_cache_create("btrfs_end_io_wq",
  86					sizeof(struct btrfs_end_io_wq),
  87					0,
  88					SLAB_MEM_SPREAD,
  89					NULL);
  90	if (!btrfs_end_io_wq_cache)
  91		return -ENOMEM;
  92	return 0;
  93}
  94
  95void __cold btrfs_end_io_wq_exit(void)
  96{
  97	kmem_cache_destroy(btrfs_end_io_wq_cache);
  98}
  99
 100/*
 101 * async submit bios are used to offload expensive checksumming
 102 * onto the worker threads.  They checksum file and metadata bios
 103 * just before they are sent down the IO stack.
 104 */
 105struct async_submit_bio {
 106	void *private_data;
 107	struct bio *bio;
 108	extent_submit_bio_start_t *submit_bio_start;
 
 
 
 109	int mirror_num;
 
 110	/*
 111	 * bio_offset is optional, can be used if the pages in the bio
 112	 * can't tell us where in the file the bio should go
 113	 */
 114	u64 bio_offset;
 115	struct btrfs_work work;
 116	blk_status_t status;
 117};
 118
 119/*
 120 * Lockdep class keys for extent_buffer->lock's in this root.  For a given
 121 * eb, the lockdep key is determined by the btrfs_root it belongs to and
 122 * the level the eb occupies in the tree.
 123 *
 124 * Different roots are used for different purposes and may nest inside each
 125 * other and they require separate keysets.  As lockdep keys should be
 126 * static, assign keysets according to the purpose of the root as indicated
 127 * by btrfs_root->root_key.objectid.  This ensures that all special purpose
 128 * roots have separate keysets.
 129 *
 130 * Lock-nesting across peer nodes is always done with the immediate parent
 131 * node locked thus preventing deadlock.  As lockdep doesn't know this, use
 132 * subclass to avoid triggering lockdep warning in such cases.
 133 *
 134 * The key is set by the readpage_end_io_hook after the buffer has passed
 135 * csum validation but before the pages are unlocked.  It is also set by
 136 * btrfs_init_new_buffer on freshly allocated blocks.
 137 *
 138 * We also add a check to make sure the highest level of the tree is the
 139 * same as our lockdep setup here.  If BTRFS_MAX_LEVEL changes, this code
 140 * needs update as well.
 141 */
 142#ifdef CONFIG_DEBUG_LOCK_ALLOC
 143# if BTRFS_MAX_LEVEL != 8
 144#  error
 145# endif
 146
 147static struct btrfs_lockdep_keyset {
 148	u64			id;		/* root objectid */
 149	const char		*name_stem;	/* lock name stem */
 150	char			names[BTRFS_MAX_LEVEL + 1][20];
 151	struct lock_class_key	keys[BTRFS_MAX_LEVEL + 1];
 152} btrfs_lockdep_keysets[] = {
 153	{ .id = BTRFS_ROOT_TREE_OBJECTID,	.name_stem = "root"	},
 154	{ .id = BTRFS_EXTENT_TREE_OBJECTID,	.name_stem = "extent"	},
 155	{ .id = BTRFS_CHUNK_TREE_OBJECTID,	.name_stem = "chunk"	},
 156	{ .id = BTRFS_DEV_TREE_OBJECTID,	.name_stem = "dev"	},
 157	{ .id = BTRFS_FS_TREE_OBJECTID,		.name_stem = "fs"	},
 158	{ .id = BTRFS_CSUM_TREE_OBJECTID,	.name_stem = "csum"	},
 159	{ .id = BTRFS_QUOTA_TREE_OBJECTID,	.name_stem = "quota"	},
 160	{ .id = BTRFS_TREE_LOG_OBJECTID,	.name_stem = "log"	},
 161	{ .id = BTRFS_TREE_RELOC_OBJECTID,	.name_stem = "treloc"	},
 162	{ .id = BTRFS_DATA_RELOC_TREE_OBJECTID,	.name_stem = "dreloc"	},
 163	{ .id = BTRFS_UUID_TREE_OBJECTID,	.name_stem = "uuid"	},
 164	{ .id = BTRFS_FREE_SPACE_TREE_OBJECTID,	.name_stem = "free-space" },
 165	{ .id = 0,				.name_stem = "tree"	},
 166};
 167
 168void __init btrfs_init_lockdep(void)
 169{
 170	int i, j;
 171
 172	/* initialize lockdep class names */
 173	for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) {
 174		struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i];
 175
 176		for (j = 0; j < ARRAY_SIZE(ks->names); j++)
 177			snprintf(ks->names[j], sizeof(ks->names[j]),
 178				 "btrfs-%s-%02d", ks->name_stem, j);
 179	}
 180}
 181
 182void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
 183				    int level)
 184{
 185	struct btrfs_lockdep_keyset *ks;
 186
 187	BUG_ON(level >= ARRAY_SIZE(ks->keys));
 188
 189	/* find the matching keyset, id 0 is the default entry */
 190	for (ks = btrfs_lockdep_keysets; ks->id; ks++)
 191		if (ks->id == objectid)
 192			break;
 193
 194	lockdep_set_class_and_name(&eb->lock,
 195				   &ks->keys[level], ks->names[level]);
 196}
 197
 198#endif
 199
 200/*
 201 * extents on the btree inode are pretty simple, there's one extent
 202 * that covers the entire device
 203 */
 204struct extent_map *btree_get_extent(struct btrfs_inode *inode,
 205		struct page *page, size_t pg_offset, u64 start, u64 len,
 206		int create)
 207{
 208	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 209	struct extent_map_tree *em_tree = &inode->extent_tree;
 210	struct extent_map *em;
 211	int ret;
 212
 213	read_lock(&em_tree->lock);
 214	em = lookup_extent_mapping(em_tree, start, len);
 215	if (em) {
 216		em->bdev = fs_info->fs_devices->latest_bdev;
 
 217		read_unlock(&em_tree->lock);
 218		goto out;
 219	}
 220	read_unlock(&em_tree->lock);
 221
 222	em = alloc_extent_map();
 223	if (!em) {
 224		em = ERR_PTR(-ENOMEM);
 225		goto out;
 226	}
 227	em->start = 0;
 228	em->len = (u64)-1;
 229	em->block_len = (u64)-1;
 230	em->block_start = 0;
 231	em->bdev = fs_info->fs_devices->latest_bdev;
 232
 233	write_lock(&em_tree->lock);
 234	ret = add_extent_mapping(em_tree, em, 0);
 235	if (ret == -EEXIST) {
 236		free_extent_map(em);
 237		em = lookup_extent_mapping(em_tree, start, len);
 238		if (!em)
 239			em = ERR_PTR(-EIO);
 240	} else if (ret) {
 241		free_extent_map(em);
 242		em = ERR_PTR(ret);
 243	}
 244	write_unlock(&em_tree->lock);
 245
 246out:
 247	return em;
 248}
 249
 
 
 
 
 
 
 
 
 
 
 250/*
 251 * Compute the csum of a btree block and store the result to provided buffer.
 252 *
 253 * Returns error if the extent buffer cannot be mapped.
 254 */
 255static int csum_tree_block(struct extent_buffer *buf, u8 *result)
 
 256{
 257	struct btrfs_fs_info *fs_info = buf->fs_info;
 258	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 259	unsigned long len;
 260	unsigned long cur_len;
 261	unsigned long offset = BTRFS_CSUM_SIZE;
 262	char *kaddr;
 263	unsigned long map_start;
 264	unsigned long map_len;
 265	int err;
 266
 267	shash->tfm = fs_info->csum_shash;
 268	crypto_shash_init(shash);
 269
 270	len = buf->len - offset;
 271
 272	while (len > 0) {
 273		/*
 274		 * Note: we don't need to check for the err == 1 case here, as
 275		 * with the given combination of 'start = BTRFS_CSUM_SIZE (32)'
 276		 * and 'min_len = 32' and the currently implemented mapping
 277		 * algorithm we cannot cross a page boundary.
 278		 */
 279		err = map_private_extent_buffer(buf, offset, 32,
 280					&kaddr, &map_start, &map_len);
 281		if (WARN_ON(err))
 282			return err;
 283		cur_len = min(len, map_len - (offset - map_start));
 284		crypto_shash_update(shash, kaddr + offset - map_start, cur_len);
 
 285		len -= cur_len;
 286		offset += cur_len;
 287	}
 288	memset(result, 0, BTRFS_CSUM_SIZE);
 
 
 
 
 
 
 289
 290	crypto_shash_final(shash, result);
 291
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 292	return 0;
 293}
 294
 295/*
 296 * we can't consider a given block up to date unless the transid of the
 297 * block matches the transid in the parent node's pointer.  This is how we
 298 * detect blocks that either didn't get written at all or got written
 299 * in the wrong place.
 300 */
 301static int verify_parent_transid(struct extent_io_tree *io_tree,
 302				 struct extent_buffer *eb, u64 parent_transid,
 303				 int atomic)
 304{
 305	struct extent_state *cached_state = NULL;
 306	int ret;
 307	bool need_lock = (current->journal_info == BTRFS_SEND_TRANS_STUB);
 
 308
 309	if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 310		return 0;
 311
 312	if (atomic)
 313		return -EAGAIN;
 314
 315	if (need_lock) {
 316		btrfs_tree_read_lock(eb);
 317		btrfs_set_lock_blocking_read(eb);
 318	}
 319
 320	lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
 321			 &cached_state);
 322	if (extent_buffer_uptodate(eb) &&
 323	    btrfs_header_generation(eb) == parent_transid) {
 324		ret = 0;
 325		goto out;
 326	}
 327	btrfs_err_rl(eb->fs_info,
 328		"parent transid verify failed on %llu wanted %llu found %llu",
 329			eb->start,
 330			parent_transid, btrfs_header_generation(eb));
 331	ret = 1;
 332
 333	/*
 334	 * Things reading via commit roots that don't have normal protection,
 335	 * like send, can have a really old block in cache that may point at a
 336	 * block that has been freed and re-allocated.  So don't clear uptodate
 337	 * if we find an eb that is under IO (dirty/writeback) because we could
 338	 * end up reading in the stale data and then writing it back out and
 339	 * making everybody very sad.
 340	 */
 341	if (!extent_buffer_under_io(eb))
 342		clear_extent_buffer_uptodate(eb);
 343out:
 344	unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
 345			     &cached_state);
 346	if (need_lock)
 347		btrfs_tree_read_unlock_blocking(eb);
 348	return ret;
 349}
 350
 351static bool btrfs_supported_super_csum(u16 csum_type)
 352{
 353	switch (csum_type) {
 354	case BTRFS_CSUM_TYPE_CRC32:
 355		return true;
 356	default:
 357		return false;
 358	}
 359}
 360
 361/*
 362 * Return 0 if the superblock checksum type matches the checksum value of that
 363 * algorithm. Pass the raw disk superblock data.
 364 */
 365static int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
 366				  char *raw_disk_sb)
 367{
 368	struct btrfs_super_block *disk_sb =
 369		(struct btrfs_super_block *)raw_disk_sb;
 370	char result[BTRFS_CSUM_SIZE];
 371	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 372
 373	shash->tfm = fs_info->csum_shash;
 374	crypto_shash_init(shash);
 375
 376	/*
 377	 * The super_block structure does not span the whole
 378	 * BTRFS_SUPER_INFO_SIZE range, we expect that the unused space is
 379	 * filled with zeros and is included in the checksum.
 380	 */
 381	crypto_shash_update(shash, raw_disk_sb + BTRFS_CSUM_SIZE,
 382			    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
 383	crypto_shash_final(shash, result);
 384
 385	if (memcmp(disk_sb->csum, result, btrfs_super_csum_size(disk_sb)))
 386		return 1;
 
 
 387
 388	return 0;
 389}
 
 
 
 
 
 
 390
 391int btrfs_verify_level_key(struct extent_buffer *eb, int level,
 392			   struct btrfs_key *first_key, u64 parent_transid)
 393{
 394	struct btrfs_fs_info *fs_info = eb->fs_info;
 395	int found_level;
 396	struct btrfs_key found_key;
 397	int ret;
 398
 399	found_level = btrfs_header_level(eb);
 400	if (found_level != level) {
 401		WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
 402		     KERN_ERR "BTRFS: tree level check failed\n");
 403		btrfs_err(fs_info,
 404"tree level mismatch detected, bytenr=%llu level expected=%u has=%u",
 405			  eb->start, level, found_level);
 406		return -EIO;
 407	}
 408
 409	if (!first_key)
 410		return 0;
 411
 412	/*
 413	 * For live tree block (new tree blocks in current transaction),
 414	 * we need proper lock context to avoid race, which is impossible here.
 415	 * So we only checks tree blocks which is read from disk, whose
 416	 * generation <= fs_info->last_trans_committed.
 417	 */
 418	if (btrfs_header_generation(eb) > fs_info->last_trans_committed)
 419		return 0;
 420
 421	/* We have @first_key, so this @eb must have at least one item */
 422	if (btrfs_header_nritems(eb) == 0) {
 423		btrfs_err(fs_info,
 424		"invalid tree nritems, bytenr=%llu nritems=0 expect >0",
 425			  eb->start);
 426		WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
 427		return -EUCLEAN;
 428	}
 429
 430	if (found_level)
 431		btrfs_node_key_to_cpu(eb, &found_key, 0);
 432	else
 433		btrfs_item_key_to_cpu(eb, &found_key, 0);
 434	ret = btrfs_comp_cpu_keys(first_key, &found_key);
 435
 436	if (ret) {
 437		WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
 438		     KERN_ERR "BTRFS: tree first key check failed\n");
 439		btrfs_err(fs_info,
 440"tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
 441			  eb->start, parent_transid, first_key->objectid,
 442			  first_key->type, first_key->offset,
 443			  found_key.objectid, found_key.type,
 444			  found_key.offset);
 445	}
 446	return ret;
 447}
 448
 449/*
 450 * helper to read a given tree block, doing retries as required when
 451 * the checksums don't match and we have alternate mirrors to try.
 452 *
 453 * @parent_transid:	expected transid, skip check if 0
 454 * @level:		expected level, mandatory check
 455 * @first_key:		expected key of first slot, skip check if NULL
 456 */
 457static int btree_read_extent_buffer_pages(struct extent_buffer *eb,
 458					  u64 parent_transid, int level,
 459					  struct btrfs_key *first_key)
 460{
 461	struct btrfs_fs_info *fs_info = eb->fs_info;
 462	struct extent_io_tree *io_tree;
 463	int failed = 0;
 464	int ret;
 465	int num_copies = 0;
 466	int mirror_num = 0;
 467	int failed_mirror = 0;
 468
 469	io_tree = &BTRFS_I(fs_info->btree_inode)->io_tree;
 
 470	while (1) {
 471		clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 472		ret = read_extent_buffer_pages(eb, WAIT_COMPLETE, mirror_num);
 
 473		if (!ret) {
 474			if (verify_parent_transid(io_tree, eb,
 475						   parent_transid, 0))
 476				ret = -EIO;
 477			else if (btrfs_verify_level_key(eb, level,
 478						first_key, parent_transid))
 479				ret = -EUCLEAN;
 480			else
 481				break;
 
 
 482		}
 483
 484		num_copies = btrfs_num_copies(fs_info,
 
 
 
 
 
 
 
 
 485					      eb->start, eb->len);
 486		if (num_copies == 1)
 487			break;
 488
 489		if (!failed_mirror) {
 490			failed = 1;
 491			failed_mirror = eb->read_mirror;
 492		}
 493
 494		mirror_num++;
 495		if (mirror_num == failed_mirror)
 496			mirror_num++;
 497
 498		if (mirror_num > num_copies)
 499			break;
 500	}
 501
 502	if (failed && !ret && failed_mirror)
 503		btrfs_repair_eb_io_failure(eb, failed_mirror);
 504
 505	return ret;
 506}
 507
 508/*
 509 * checksum a dirty tree block before IO.  This has extra checks to make sure
 510 * we only fill in the checksum field in the first page of a multi-page block
 511 */
 512
 513static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct page *page)
 514{
 515	u64 start = page_offset(page);
 516	u64 found_start;
 517	u8 result[BTRFS_CSUM_SIZE];
 518	u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
 519	struct extent_buffer *eb;
 520	int ret;
 521
 522	eb = (struct extent_buffer *)page->private;
 523	if (page != eb->pages[0])
 524		return 0;
 525
 526	found_start = btrfs_header_bytenr(eb);
 527	/*
 528	 * Please do not consolidate these warnings into a single if.
 529	 * It is useful to know what went wrong.
 530	 */
 531	if (WARN_ON(found_start != start))
 532		return -EUCLEAN;
 533	if (WARN_ON(!PageUptodate(page)))
 534		return -EUCLEAN;
 535
 536	ASSERT(memcmp_extent_buffer(eb, fs_info->fs_devices->metadata_uuid,
 537			btrfs_header_fsid(), BTRFS_FSID_SIZE) == 0);
 538
 539	if (csum_tree_block(eb, result))
 540		return -EINVAL;
 541
 542	if (btrfs_header_level(eb))
 543		ret = btrfs_check_node(eb);
 544	else
 545		ret = btrfs_check_leaf_full(eb);
 546
 547	if (ret < 0) {
 548		btrfs_err(fs_info,
 549		"block=%llu write time tree block corruption detected",
 550			  eb->start);
 551		return ret;
 552	}
 553	write_extent_buffer(eb, result, 0, csum_size);
 554
 555	return 0;
 556}
 557
 558static int check_tree_block_fsid(struct extent_buffer *eb)
 
 559{
 560	struct btrfs_fs_info *fs_info = eb->fs_info;
 561	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
 562	u8 fsid[BTRFS_FSID_SIZE];
 563	int ret = 1;
 564
 565	read_extent_buffer(eb, fsid, btrfs_header_fsid(), BTRFS_FSID_SIZE);
 566	while (fs_devices) {
 567		u8 *metadata_uuid;
 568
 569		/*
 570		 * Checking the incompat flag is only valid for the current
 571		 * fs. For seed devices it's forbidden to have their uuid
 572		 * changed so reading ->fsid in this case is fine
 573		 */
 574		if (fs_devices == fs_info->fs_devices &&
 575		    btrfs_fs_incompat(fs_info, METADATA_UUID))
 576			metadata_uuid = fs_devices->metadata_uuid;
 577		else
 578			metadata_uuid = fs_devices->fsid;
 579
 580		if (!memcmp(fsid, metadata_uuid, BTRFS_FSID_SIZE)) {
 581			ret = 0;
 582			break;
 583		}
 584		fs_devices = fs_devices->seed;
 585	}
 586	return ret;
 587}
 588
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 589static int btree_readpage_end_io_hook(struct btrfs_io_bio *io_bio,
 590				      u64 phy_offset, struct page *page,
 591				      u64 start, u64 end, int mirror)
 592{
 593	u64 found_start;
 594	int found_level;
 595	struct extent_buffer *eb;
 596	struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 597	struct btrfs_fs_info *fs_info = root->fs_info;
 598	u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
 599	int ret = 0;
 600	u8 result[BTRFS_CSUM_SIZE];
 601	int reads_done;
 602
 603	if (!page->private)
 604		goto out;
 605
 606	eb = (struct extent_buffer *)page->private;
 607
 608	/* the pending IO might have been the only thing that kept this buffer
 609	 * in memory.  Make sure we have a ref for all this other checks
 610	 */
 611	extent_buffer_get(eb);
 612
 613	reads_done = atomic_dec_and_test(&eb->io_pages);
 614	if (!reads_done)
 615		goto err;
 616
 617	eb->read_mirror = mirror;
 618	if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
 619		ret = -EIO;
 620		goto err;
 621	}
 622
 623	found_start = btrfs_header_bytenr(eb);
 624	if (found_start != eb->start) {
 625		btrfs_err_rl(fs_info, "bad tree block start, want %llu have %llu",
 626			     eb->start, found_start);
 
 627		ret = -EIO;
 628		goto err;
 629	}
 630	if (check_tree_block_fsid(eb)) {
 631		btrfs_err_rl(fs_info, "bad fsid on block %llu",
 632			     eb->start);
 633		ret = -EIO;
 634		goto err;
 635	}
 636	found_level = btrfs_header_level(eb);
 637	if (found_level >= BTRFS_MAX_LEVEL) {
 638		btrfs_err(fs_info, "bad tree block level %d on %llu",
 639			  (int)btrfs_header_level(eb), eb->start);
 640		ret = -EIO;
 641		goto err;
 642	}
 643
 644	btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb),
 645				       eb, found_level);
 646
 647	ret = csum_tree_block(eb, result);
 648	if (ret)
 649		goto err;
 650
 651	if (memcmp_extent_buffer(eb, result, 0, csum_size)) {
 652		u32 val;
 653		u32 found = 0;
 654
 655		memcpy(&found, result, csum_size);
 656
 657		read_extent_buffer(eb, &val, 0, csum_size);
 658		btrfs_warn_rl(fs_info,
 659		"%s checksum verify failed on %llu wanted %x found %x level %d",
 660			      fs_info->sb->s_id, eb->start,
 661			      val, found, btrfs_header_level(eb));
 662		ret = -EUCLEAN;
 663		goto err;
 664	}
 665
 666	/*
 667	 * If this is a leaf block and it is corrupt, set the corrupt bit so
 668	 * that we don't try and read the other copies of this block, just
 669	 * return -EIO.
 670	 */
 671	if (found_level == 0 && btrfs_check_leaf_full(eb)) {
 672		set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 673		ret = -EIO;
 674	}
 675
 676	if (found_level > 0 && btrfs_check_node(eb))
 677		ret = -EIO;
 678
 679	if (!ret)
 680		set_extent_buffer_uptodate(eb);
 681	else
 682		btrfs_err(fs_info,
 683			  "block=%llu read time tree block corruption detected",
 684			  eb->start);
 685err:
 686	if (reads_done &&
 687	    test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
 688		btree_readahead_hook(eb, ret);
 689
 690	if (ret) {
 691		/*
 692		 * our io error hook is going to dec the io pages
 693		 * again, we have to make sure it has something
 694		 * to decrement
 695		 */
 696		atomic_inc(&eb->io_pages);
 697		clear_extent_buffer_uptodate(eb);
 698	}
 699	free_extent_buffer(eb);
 700out:
 701	return ret;
 702}
 703
 704static void end_workqueue_bio(struct bio *bio)
 705{
 706	struct btrfs_end_io_wq *end_io_wq = bio->bi_private;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 707	struct btrfs_fs_info *fs_info;
 708	struct btrfs_workqueue *wq;
 709	btrfs_work_func_t func;
 710
 711	fs_info = end_io_wq->info;
 712	end_io_wq->status = bio->bi_status;
 
 713
 714	if (bio_op(bio) == REQ_OP_WRITE) {
 715		if (end_io_wq->metadata == BTRFS_WQ_ENDIO_METADATA) {
 716			wq = fs_info->endio_meta_write_workers;
 717			func = btrfs_endio_meta_write_helper;
 718		} else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_FREE_SPACE) {
 719			wq = fs_info->endio_freespace_worker;
 720			func = btrfs_freespace_write_helper;
 721		} else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56) {
 722			wq = fs_info->endio_raid56_workers;
 723			func = btrfs_endio_raid56_helper;
 724		} else {
 725			wq = fs_info->endio_write_workers;
 726			func = btrfs_endio_write_helper;
 727		}
 728	} else {
 729		if (unlikely(end_io_wq->metadata ==
 730			     BTRFS_WQ_ENDIO_DIO_REPAIR)) {
 731			wq = fs_info->endio_repair_workers;
 732			func = btrfs_endio_repair_helper;
 733		} else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56) {
 734			wq = fs_info->endio_raid56_workers;
 735			func = btrfs_endio_raid56_helper;
 736		} else if (end_io_wq->metadata) {
 737			wq = fs_info->endio_meta_workers;
 738			func = btrfs_endio_meta_helper;
 739		} else {
 740			wq = fs_info->endio_workers;
 741			func = btrfs_endio_helper;
 742		}
 743	}
 744
 745	btrfs_init_work(&end_io_wq->work, func, end_workqueue_fn, NULL, NULL);
 746	btrfs_queue_work(wq, &end_io_wq->work);
 747}
 748
 749blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
 750			enum btrfs_wq_endio_type metadata)
 
 
 
 
 
 
 
 
 751{
 752	struct btrfs_end_io_wq *end_io_wq;
 753
 754	end_io_wq = kmem_cache_alloc(btrfs_end_io_wq_cache, GFP_NOFS);
 755	if (!end_io_wq)
 756		return BLK_STS_RESOURCE;
 757
 758	end_io_wq->private = bio->bi_private;
 759	end_io_wq->end_io = bio->bi_end_io;
 760	end_io_wq->info = info;
 761	end_io_wq->status = 0;
 762	end_io_wq->bio = bio;
 763	end_io_wq->metadata = metadata;
 764
 765	bio->bi_private = end_io_wq;
 766	bio->bi_end_io = end_workqueue_bio;
 767	return 0;
 768}
 769
 
 
 
 
 
 
 
 
 770static void run_one_async_start(struct btrfs_work *work)
 771{
 772	struct async_submit_bio *async;
 773	blk_status_t ret;
 774
 775	async = container_of(work, struct  async_submit_bio, work);
 776	ret = async->submit_bio_start(async->private_data, async->bio,
 
 777				      async->bio_offset);
 778	if (ret)
 779		async->status = ret;
 780}
 781
 782/*
 783 * In order to insert checksums into the metadata in large chunks, we wait
 784 * until bio submission time.   All the pages in the bio are checksummed and
 785 * sums are attached onto the ordered extent record.
 786 *
 787 * At IO completion time the csums attached on the ordered extent record are
 788 * inserted into the tree.
 789 */
 790static void run_one_async_done(struct btrfs_work *work)
 791{
 
 792	struct async_submit_bio *async;
 793	struct inode *inode;
 794	blk_status_t ret;
 795
 796	async = container_of(work, struct  async_submit_bio, work);
 797	inode = async->private_data;
 798
 799	/* If an error occurred we just want to clean up the bio and move on */
 800	if (async->status) {
 801		async->bio->bi_status = async->status;
 802		bio_endio(async->bio);
 
 
 
 
 
 
 803		return;
 804	}
 805
 806	ret = btrfs_map_bio(btrfs_sb(inode->i_sb), async->bio,
 807			async->mirror_num, 1);
 808	if (ret) {
 809		async->bio->bi_status = ret;
 810		bio_endio(async->bio);
 811	}
 812}
 813
 814static void run_one_async_free(struct btrfs_work *work)
 815{
 816	struct async_submit_bio *async;
 817
 818	async = container_of(work, struct  async_submit_bio, work);
 819	kfree(async);
 820}
 821
 822blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
 823				 int mirror_num, unsigned long bio_flags,
 824				 u64 bio_offset, void *private_data,
 825				 extent_submit_bio_start_t *submit_bio_start)
 
 
 826{
 827	struct async_submit_bio *async;
 828
 829	async = kmalloc(sizeof(*async), GFP_NOFS);
 830	if (!async)
 831		return BLK_STS_RESOURCE;
 832
 833	async->private_data = private_data;
 
 834	async->bio = bio;
 835	async->mirror_num = mirror_num;
 836	async->submit_bio_start = submit_bio_start;
 
 837
 838	btrfs_init_work(&async->work, btrfs_worker_helper, run_one_async_start,
 839			run_one_async_done, run_one_async_free);
 840
 
 841	async->bio_offset = bio_offset;
 842
 843	async->status = 0;
 844
 845	if (op_is_sync(bio->bi_opf))
 
 
 846		btrfs_set_work_high_priority(&async->work);
 847
 848	btrfs_queue_work(fs_info->workers, &async->work);
 
 
 
 
 
 
 
 849	return 0;
 850}
 851
 852static blk_status_t btree_csum_one_bio(struct bio *bio)
 853{
 854	struct bio_vec *bvec;
 855	struct btrfs_root *root;
 856	int ret = 0;
 857	struct bvec_iter_all iter_all;
 858
 859	ASSERT(!bio_flagged(bio, BIO_CLONED));
 860	bio_for_each_segment_all(bvec, bio, iter_all) {
 861		root = BTRFS_I(bvec->bv_page->mapping->host)->root;
 862		ret = csum_dirty_buffer(root->fs_info, bvec->bv_page);
 863		if (ret)
 864			break;
 865	}
 866
 867	return errno_to_blk_status(ret);
 868}
 869
 870static blk_status_t btree_submit_bio_start(void *private_data, struct bio *bio,
 871					     u64 bio_offset)
 
 
 872{
 873	/*
 874	 * when we're called for a write, we're already in the async
 875	 * submission context.  Just jump into btrfs_map_bio
 876	 */
 877	return btree_csum_one_bio(bio);
 878}
 879
 880static int check_async_write(struct btrfs_fs_info *fs_info,
 881			     struct btrfs_inode *bi)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 882{
 883	if (atomic_read(&bi->sync_writers))
 884		return 0;
 885	if (test_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags))
 
 886		return 0;
 
 887	return 1;
 888}
 889
 890static blk_status_t btree_submit_bio_hook(struct inode *inode, struct bio *bio,
 891					  int mirror_num,
 892					  unsigned long bio_flags)
 893{
 894	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 895	int async = check_async_write(fs_info, BTRFS_I(inode));
 896	blk_status_t ret;
 897
 898	if (bio_op(bio) != REQ_OP_WRITE) {
 899		/*
 900		 * called for a read, do the setup so that checksum validation
 901		 * can happen in the async kernel threads
 902		 */
 903		ret = btrfs_bio_wq_end_io(fs_info, bio,
 904					  BTRFS_WQ_ENDIO_METADATA);
 905		if (ret)
 906			goto out_w_error;
 907		ret = btrfs_map_bio(fs_info, bio, mirror_num, 0);
 
 908	} else if (!async) {
 909		ret = btree_csum_one_bio(bio);
 910		if (ret)
 911			goto out_w_error;
 912		ret = btrfs_map_bio(fs_info, bio, mirror_num, 0);
 
 913	} else {
 914		/*
 915		 * kthread helpers are used to submit writes so that
 916		 * checksumming can happen in parallel across all CPUs
 917		 */
 918		ret = btrfs_wq_submit_bio(fs_info, bio, mirror_num, 0,
 919					  0, inode, btree_submit_bio_start);
 
 
 
 920	}
 921
 922	if (ret)
 923		goto out_w_error;
 924	return 0;
 925
 926out_w_error:
 927	bio->bi_status = ret;
 928	bio_endio(bio);
 929	return ret;
 930}
 931
 932#ifdef CONFIG_MIGRATION
 933static int btree_migratepage(struct address_space *mapping,
 934			struct page *newpage, struct page *page,
 935			enum migrate_mode mode)
 936{
 937	/*
 938	 * we can't safely write a btree page from here,
 939	 * we haven't done the locking hook
 940	 */
 941	if (PageDirty(page))
 942		return -EAGAIN;
 943	/*
 944	 * Buffers may be managed in a filesystem specific way.
 945	 * We must have no buffers or drop them.
 946	 */
 947	if (page_has_private(page) &&
 948	    !try_to_release_page(page, GFP_KERNEL))
 949		return -EAGAIN;
 950	return migrate_page(mapping, newpage, page, mode);
 951}
 952#endif
 953
 954
 955static int btree_writepages(struct address_space *mapping,
 956			    struct writeback_control *wbc)
 957{
 958	struct btrfs_fs_info *fs_info;
 959	int ret;
 960
 961	if (wbc->sync_mode == WB_SYNC_NONE) {
 962
 963		if (wbc->for_kupdate)
 964			return 0;
 965
 966		fs_info = BTRFS_I(mapping->host)->root->fs_info;
 967		/* this is a bit racy, but that's ok */
 968		ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
 969					     BTRFS_DIRTY_METADATA_THRESH,
 970					     fs_info->dirty_metadata_batch);
 971		if (ret < 0)
 972			return 0;
 973	}
 974	return btree_write_cache_pages(mapping, wbc);
 975}
 976
 977static int btree_readpage(struct file *file, struct page *page)
 978{
 979	struct extent_io_tree *tree;
 980	tree = &BTRFS_I(page->mapping->host)->io_tree;
 981	return extent_read_full_page(tree, page, btree_get_extent, 0);
 982}
 983
 984static int btree_releasepage(struct page *page, gfp_t gfp_flags)
 985{
 986	if (PageWriteback(page) || PageDirty(page))
 987		return 0;
 988
 989	return try_release_extent_buffer(page);
 990}
 991
 992static void btree_invalidatepage(struct page *page, unsigned int offset,
 993				 unsigned int length)
 994{
 995	struct extent_io_tree *tree;
 996	tree = &BTRFS_I(page->mapping->host)->io_tree;
 997	extent_invalidatepage(tree, page, offset);
 998	btree_releasepage(page, GFP_NOFS);
 999	if (PagePrivate(page)) {
1000		btrfs_warn(BTRFS_I(page->mapping->host)->root->fs_info,
1001			   "page private not zero on page %llu",
1002			   (unsigned long long)page_offset(page));
1003		ClearPagePrivate(page);
1004		set_page_private(page, 0);
1005		put_page(page);
1006	}
1007}
1008
1009static int btree_set_page_dirty(struct page *page)
1010{
1011#ifdef DEBUG
1012	struct extent_buffer *eb;
1013
1014	BUG_ON(!PagePrivate(page));
1015	eb = (struct extent_buffer *)page->private;
1016	BUG_ON(!eb);
1017	BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
1018	BUG_ON(!atomic_read(&eb->refs));
1019	btrfs_assert_tree_locked(eb);
1020#endif
1021	return __set_page_dirty_nobuffers(page);
1022}
1023
1024static const struct address_space_operations btree_aops = {
1025	.readpage	= btree_readpage,
1026	.writepages	= btree_writepages,
1027	.releasepage	= btree_releasepage,
1028	.invalidatepage = btree_invalidatepage,
1029#ifdef CONFIG_MIGRATION
1030	.migratepage	= btree_migratepage,
1031#endif
1032	.set_page_dirty = btree_set_page_dirty,
1033};
1034
1035void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr)
 
1036{
1037	struct extent_buffer *buf = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1038	int ret;
1039
1040	buf = btrfs_find_create_tree_block(fs_info, bytenr);
1041	if (IS_ERR(buf))
1042		return;
1043
1044	ret = read_extent_buffer_pages(buf, WAIT_NONE, 0);
1045	if (ret < 0)
1046		free_extent_buffer_stale(buf);
1047	else
 
1048		free_extent_buffer(buf);
 
 
 
 
 
 
 
 
 
 
 
 
1049}
1050
1051struct extent_buffer *btrfs_find_create_tree_block(
1052						struct btrfs_fs_info *fs_info,
1053						u64 bytenr)
1054{
1055	if (btrfs_is_testing(fs_info))
1056		return alloc_test_extent_buffer(fs_info, bytenr);
1057	return alloc_extent_buffer(fs_info, bytenr);
1058}
1059
1060/*
1061 * Read tree block at logical address @bytenr and do variant basic but critical
1062 * verification.
1063 *
1064 * @parent_transid:	expected transid of this tree block, skip check if 0
1065 * @level:		expected level, mandatory check
1066 * @first_key:		expected key in slot 0, skip check if NULL
1067 */
1068struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
1069				      u64 parent_transid, int level,
1070				      struct btrfs_key *first_key)
 
 
 
 
 
 
 
 
 
 
1071{
1072	struct extent_buffer *buf = NULL;
1073	int ret;
1074
1075	buf = btrfs_find_create_tree_block(fs_info, bytenr);
1076	if (IS_ERR(buf))
1077		return buf;
1078
1079	ret = btree_read_extent_buffer_pages(buf, parent_transid,
1080					     level, first_key);
1081	if (ret) {
1082		free_extent_buffer_stale(buf);
1083		return ERR_PTR(ret);
1084	}
1085	return buf;
1086
1087}
1088
1089void btrfs_clean_tree_block(struct extent_buffer *buf)
 
1090{
1091	struct btrfs_fs_info *fs_info = buf->fs_info;
 
1092	if (btrfs_header_generation(buf) ==
1093	    fs_info->running_transaction->transid) {
1094		btrfs_assert_tree_locked(buf);
1095
1096		if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
1097			percpu_counter_add_batch(&fs_info->dirty_metadata_bytes,
1098						 -buf->len,
1099						 fs_info->dirty_metadata_batch);
1100			/* ugh, clear_extent_buffer_dirty needs to lock the page */
1101			btrfs_set_lock_blocking_write(buf);
1102			clear_extent_buffer_dirty(buf);
1103		}
1104	}
1105}
1106
1107static struct btrfs_subvolume_writers *btrfs_alloc_subvolume_writers(void)
1108{
1109	struct btrfs_subvolume_writers *writers;
1110	int ret;
1111
1112	writers = kmalloc(sizeof(*writers), GFP_NOFS);
1113	if (!writers)
1114		return ERR_PTR(-ENOMEM);
1115
1116	ret = percpu_counter_init(&writers->counter, 0, GFP_NOFS);
1117	if (ret < 0) {
1118		kfree(writers);
1119		return ERR_PTR(ret);
1120	}
1121
1122	init_waitqueue_head(&writers->wait);
1123	return writers;
1124}
1125
1126static void
1127btrfs_free_subvolume_writers(struct btrfs_subvolume_writers *writers)
1128{
1129	percpu_counter_destroy(&writers->counter);
1130	kfree(writers);
1131}
1132
1133static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
 
 
1134			 u64 objectid)
1135{
1136	bool dummy = test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state);
1137	root->node = NULL;
1138	root->commit_root = NULL;
1139	root->state = 0;
 
 
 
 
 
 
 
1140	root->orphan_cleanup_state = 0;
1141
 
1142	root->last_trans = 0;
1143	root->highest_objectid = 0;
1144	root->nr_delalloc_inodes = 0;
1145	root->nr_ordered_extents = 0;
 
1146	root->inode_tree = RB_ROOT;
1147	INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
1148	root->block_rsv = NULL;
 
1149
1150	INIT_LIST_HEAD(&root->dirty_list);
1151	INIT_LIST_HEAD(&root->root_list);
1152	INIT_LIST_HEAD(&root->delalloc_inodes);
1153	INIT_LIST_HEAD(&root->delalloc_root);
1154	INIT_LIST_HEAD(&root->ordered_extents);
1155	INIT_LIST_HEAD(&root->ordered_root);
1156	INIT_LIST_HEAD(&root->reloc_dirty_list);
1157	INIT_LIST_HEAD(&root->logged_list[0]);
1158	INIT_LIST_HEAD(&root->logged_list[1]);
 
1159	spin_lock_init(&root->inode_lock);
1160	spin_lock_init(&root->delalloc_lock);
1161	spin_lock_init(&root->ordered_extent_lock);
1162	spin_lock_init(&root->accounting_lock);
1163	spin_lock_init(&root->log_extents_lock[0]);
1164	spin_lock_init(&root->log_extents_lock[1]);
1165	spin_lock_init(&root->qgroup_meta_rsv_lock);
1166	mutex_init(&root->objectid_mutex);
1167	mutex_init(&root->log_mutex);
1168	mutex_init(&root->ordered_extent_mutex);
1169	mutex_init(&root->delalloc_mutex);
1170	init_waitqueue_head(&root->log_writer_wait);
1171	init_waitqueue_head(&root->log_commit_wait[0]);
1172	init_waitqueue_head(&root->log_commit_wait[1]);
1173	INIT_LIST_HEAD(&root->log_ctxs[0]);
1174	INIT_LIST_HEAD(&root->log_ctxs[1]);
1175	atomic_set(&root->log_commit[0], 0);
1176	atomic_set(&root->log_commit[1], 0);
1177	atomic_set(&root->log_writers, 0);
1178	atomic_set(&root->log_batch, 0);
1179	refcount_set(&root->refs, 1);
1180	atomic_set(&root->will_be_snapshotted, 0);
1181	atomic_set(&root->snapshot_force_cow, 0);
1182	atomic_set(&root->nr_swapfiles, 0);
1183	root->log_transid = 0;
1184	root->log_transid_committed = -1;
1185	root->last_log_commit = 0;
1186	if (!dummy)
1187		extent_io_tree_init(fs_info, &root->dirty_log_pages,
1188				    IO_TREE_ROOT_DIRTY_LOG_PAGES, NULL);
1189
1190	memset(&root->root_key, 0, sizeof(root->root_key));
1191	memset(&root->root_item, 0, sizeof(root->root_item));
1192	memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
1193	if (!dummy)
 
1194		root->defrag_trans_start = fs_info->generation;
1195	else
1196		root->defrag_trans_start = 0;
 
 
1197	root->root_key.objectid = objectid;
1198	root->anon_dev = 0;
1199
1200	spin_lock_init(&root->root_item_lock);
1201	btrfs_qgroup_init_swapped_blocks(&root->swapped_blocks);
1202}
1203
1204static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info,
1205		gfp_t flags)
1206{
1207	struct btrfs_root *root = kzalloc(sizeof(*root), flags);
1208	if (root)
1209		root->fs_info = fs_info;
1210	return root;
1211}
1212
1213#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
1214/* Should only be used by the testing infrastructure */
1215struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info)
1216{
1217	struct btrfs_root *root;
1218
1219	if (!fs_info)
1220		return ERR_PTR(-EINVAL);
1221
1222	root = btrfs_alloc_root(fs_info, GFP_KERNEL);
1223	if (!root)
1224		return ERR_PTR(-ENOMEM);
1225
1226	/* We don't use the stripesize in selftest, set it as sectorsize */
1227	__setup_root(root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
1228	root->alloc_bytenr = 0;
1229
1230	return root;
1231}
1232#endif
1233
1234struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
 
1235				     u64 objectid)
1236{
1237	struct btrfs_fs_info *fs_info = trans->fs_info;
1238	struct extent_buffer *leaf;
1239	struct btrfs_root *tree_root = fs_info->tree_root;
1240	struct btrfs_root *root;
1241	struct btrfs_key key;
1242	unsigned int nofs_flag;
1243	int ret = 0;
1244	uuid_le uuid = NULL_UUID_LE;
1245
1246	/*
1247	 * We're holding a transaction handle, so use a NOFS memory allocation
1248	 * context to avoid deadlock if reclaim happens.
1249	 */
1250	nofs_flag = memalloc_nofs_save();
1251	root = btrfs_alloc_root(fs_info, GFP_KERNEL);
1252	memalloc_nofs_restore(nofs_flag);
1253	if (!root)
1254		return ERR_PTR(-ENOMEM);
1255
1256	__setup_root(root, fs_info, objectid);
 
 
1257	root->root_key.objectid = objectid;
1258	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1259	root->root_key.offset = 0;
1260
1261	leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
 
1262	if (IS_ERR(leaf)) {
1263		ret = PTR_ERR(leaf);
1264		leaf = NULL;
1265		goto fail;
1266	}
1267
 
 
 
 
 
1268	root->node = leaf;
 
 
 
 
 
 
1269	btrfs_mark_buffer_dirty(leaf);
1270
1271	root->commit_root = btrfs_root_node(root);
1272	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
 
1273
1274	root->root_item.flags = 0;
1275	root->root_item.byte_limit = 0;
1276	btrfs_set_root_bytenr(&root->root_item, leaf->start);
1277	btrfs_set_root_generation(&root->root_item, trans->transid);
1278	btrfs_set_root_level(&root->root_item, 0);
1279	btrfs_set_root_refs(&root->root_item, 1);
1280	btrfs_set_root_used(&root->root_item, leaf->len);
1281	btrfs_set_root_last_snapshot(&root->root_item, 0);
1282	btrfs_set_root_dirid(&root->root_item, 0);
1283	if (is_fstree(objectid))
1284		uuid_le_gen(&uuid);
1285	memcpy(root->root_item.uuid, uuid.b, BTRFS_UUID_SIZE);
1286	root->root_item.drop_level = 0;
1287
1288	key.objectid = objectid;
1289	key.type = BTRFS_ROOT_ITEM_KEY;
1290	key.offset = 0;
1291	ret = btrfs_insert_root(trans, tree_root, &key, &root->root_item);
1292	if (ret)
1293		goto fail;
1294
1295	btrfs_tree_unlock(leaf);
1296
1297	return root;
1298
1299fail:
1300	if (leaf) {
1301		btrfs_tree_unlock(leaf);
1302		free_extent_buffer(root->commit_root);
1303		free_extent_buffer(leaf);
1304	}
1305	kfree(root);
1306
1307	return ERR_PTR(ret);
1308}
1309
1310static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
1311					 struct btrfs_fs_info *fs_info)
1312{
1313	struct btrfs_root *root;
 
1314	struct extent_buffer *leaf;
1315
1316	root = btrfs_alloc_root(fs_info, GFP_NOFS);
1317	if (!root)
1318		return ERR_PTR(-ENOMEM);
1319
1320	__setup_root(root, fs_info, BTRFS_TREE_LOG_OBJECTID);
 
 
1321
1322	root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1323	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1324	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
1325
1326	/*
1327	 * DON'T set REF_COWS for log trees
1328	 *
1329	 * log trees do not get reference counted because they go away
1330	 * before a real commit is actually done.  They do store pointers
1331	 * to file data extents, and those reference counts still get
1332	 * updated (along with back refs to the log tree).
1333	 */
 
1334
1335	leaf = btrfs_alloc_tree_block(trans, root, 0, BTRFS_TREE_LOG_OBJECTID,
1336			NULL, 0, 0, 0);
 
1337	if (IS_ERR(leaf)) {
1338		kfree(root);
1339		return ERR_CAST(leaf);
1340	}
1341
 
 
 
 
 
1342	root->node = leaf;
1343
 
 
1344	btrfs_mark_buffer_dirty(root->node);
1345	btrfs_tree_unlock(root->node);
1346	return root;
1347}
1348
1349int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1350			     struct btrfs_fs_info *fs_info)
1351{
1352	struct btrfs_root *log_root;
1353
1354	log_root = alloc_log_tree(trans, fs_info);
1355	if (IS_ERR(log_root))
1356		return PTR_ERR(log_root);
1357	WARN_ON(fs_info->log_root_tree);
1358	fs_info->log_root_tree = log_root;
1359	return 0;
1360}
1361
1362int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1363		       struct btrfs_root *root)
1364{
1365	struct btrfs_fs_info *fs_info = root->fs_info;
1366	struct btrfs_root *log_root;
1367	struct btrfs_inode_item *inode_item;
1368
1369	log_root = alloc_log_tree(trans, fs_info);
1370	if (IS_ERR(log_root))
1371		return PTR_ERR(log_root);
1372
1373	log_root->last_trans = trans->transid;
1374	log_root->root_key.offset = root->root_key.objectid;
1375
1376	inode_item = &log_root->root_item.inode;
1377	btrfs_set_stack_inode_generation(inode_item, 1);
1378	btrfs_set_stack_inode_size(inode_item, 3);
1379	btrfs_set_stack_inode_nlink(inode_item, 1);
1380	btrfs_set_stack_inode_nbytes(inode_item,
1381				     fs_info->nodesize);
1382	btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
1383
1384	btrfs_set_root_node(&log_root->root_item, log_root->node);
1385
1386	WARN_ON(root->log_root);
1387	root->log_root = log_root;
1388	root->log_transid = 0;
1389	root->log_transid_committed = -1;
1390	root->last_log_commit = 0;
1391	return 0;
1392}
1393
1394static struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
1395					       struct btrfs_key *key)
1396{
1397	struct btrfs_root *root;
1398	struct btrfs_fs_info *fs_info = tree_root->fs_info;
1399	struct btrfs_path *path;
1400	u64 generation;
 
1401	int ret;
1402	int level;
1403
1404	path = btrfs_alloc_path();
1405	if (!path)
1406		return ERR_PTR(-ENOMEM);
1407
1408	root = btrfs_alloc_root(fs_info, GFP_NOFS);
1409	if (!root) {
1410		ret = -ENOMEM;
1411		goto alloc_fail;
1412	}
1413
1414	__setup_root(root, fs_info, key->objectid);
 
 
1415
1416	ret = btrfs_find_root(tree_root, key, path,
1417			      &root->root_item, &root->root_key);
1418	if (ret) {
1419		if (ret > 0)
1420			ret = -ENOENT;
1421		goto find_fail;
1422	}
1423
1424	generation = btrfs_root_generation(&root->root_item);
1425	level = btrfs_root_level(&root->root_item);
1426	root->node = read_tree_block(fs_info,
1427				     btrfs_root_bytenr(&root->root_item),
1428				     generation, level, NULL);
1429	if (IS_ERR(root->node)) {
1430		ret = PTR_ERR(root->node);
1431		goto find_fail;
1432	} else if (!btrfs_buffer_uptodate(root->node, generation, 0)) {
1433		ret = -EIO;
1434		free_extent_buffer(root->node);
1435		goto find_fail;
1436	}
1437	root->commit_root = btrfs_root_node(root);
1438out:
1439	btrfs_free_path(path);
1440	return root;
1441
 
 
1442find_fail:
1443	kfree(root);
1444alloc_fail:
1445	root = ERR_PTR(ret);
1446	goto out;
1447}
1448
1449struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root,
1450				      struct btrfs_key *location)
1451{
1452	struct btrfs_root *root;
1453
1454	root = btrfs_read_tree_root(tree_root, location);
1455	if (IS_ERR(root))
1456		return root;
1457
1458	if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
1459		set_bit(BTRFS_ROOT_REF_COWS, &root->state);
1460		btrfs_check_and_init_root_item(&root->root_item);
1461	}
1462
1463	return root;
1464}
1465
1466int btrfs_init_fs_root(struct btrfs_root *root)
1467{
1468	int ret;
1469	struct btrfs_subvolume_writers *writers;
1470
1471	root->free_ino_ctl = kzalloc(sizeof(*root->free_ino_ctl), GFP_NOFS);
1472	root->free_ino_pinned = kzalloc(sizeof(*root->free_ino_pinned),
1473					GFP_NOFS);
1474	if (!root->free_ino_pinned || !root->free_ino_ctl) {
1475		ret = -ENOMEM;
1476		goto fail;
1477	}
1478
1479	writers = btrfs_alloc_subvolume_writers();
1480	if (IS_ERR(writers)) {
1481		ret = PTR_ERR(writers);
1482		goto fail;
1483	}
1484	root->subv_writers = writers;
1485
1486	btrfs_init_free_ino_ctl(root);
1487	spin_lock_init(&root->ino_cache_lock);
1488	init_waitqueue_head(&root->ino_cache_wait);
1489
1490	ret = get_anon_bdev(&root->anon_dev);
1491	if (ret)
1492		goto fail;
1493
1494	mutex_lock(&root->objectid_mutex);
1495	ret = btrfs_find_highest_objectid(root,
1496					&root->highest_objectid);
1497	if (ret) {
1498		mutex_unlock(&root->objectid_mutex);
1499		goto fail;
1500	}
1501
1502	ASSERT(root->highest_objectid <= BTRFS_LAST_FREE_OBJECTID);
1503
1504	mutex_unlock(&root->objectid_mutex);
1505
1506	return 0;
 
 
 
1507fail:
1508	/* The caller is responsible to call btrfs_free_fs_root */
 
1509	return ret;
1510}
1511
1512struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
1513					u64 root_id)
1514{
1515	struct btrfs_root *root;
1516
1517	spin_lock(&fs_info->fs_roots_radix_lock);
1518	root = radix_tree_lookup(&fs_info->fs_roots_radix,
1519				 (unsigned long)root_id);
1520	spin_unlock(&fs_info->fs_roots_radix_lock);
1521	return root;
1522}
1523
1524int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
1525			 struct btrfs_root *root)
1526{
1527	int ret;
1528
1529	ret = radix_tree_preload(GFP_NOFS);
1530	if (ret)
1531		return ret;
1532
1533	spin_lock(&fs_info->fs_roots_radix_lock);
1534	ret = radix_tree_insert(&fs_info->fs_roots_radix,
1535				(unsigned long)root->root_key.objectid,
1536				root);
1537	if (ret == 0)
1538		set_bit(BTRFS_ROOT_IN_RADIX, &root->state);
1539	spin_unlock(&fs_info->fs_roots_radix_lock);
1540	radix_tree_preload_end();
1541
1542	return ret;
1543}
1544
1545struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
1546				     struct btrfs_key *location,
1547				     bool check_ref)
1548{
1549	struct btrfs_root *root;
1550	struct btrfs_path *path;
1551	struct btrfs_key key;
1552	int ret;
1553
1554	if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1555		return fs_info->tree_root;
1556	if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
1557		return fs_info->extent_root;
1558	if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
1559		return fs_info->chunk_root;
1560	if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
1561		return fs_info->dev_root;
1562	if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
1563		return fs_info->csum_root;
1564	if (location->objectid == BTRFS_QUOTA_TREE_OBJECTID)
1565		return fs_info->quota_root ? fs_info->quota_root :
1566					     ERR_PTR(-ENOENT);
1567	if (location->objectid == BTRFS_UUID_TREE_OBJECTID)
1568		return fs_info->uuid_root ? fs_info->uuid_root :
1569					    ERR_PTR(-ENOENT);
1570	if (location->objectid == BTRFS_FREE_SPACE_TREE_OBJECTID)
1571		return fs_info->free_space_root ? fs_info->free_space_root :
1572						  ERR_PTR(-ENOENT);
1573again:
1574	root = btrfs_lookup_fs_root(fs_info, location->objectid);
1575	if (root) {
1576		if (check_ref && btrfs_root_refs(&root->root_item) == 0)
1577			return ERR_PTR(-ENOENT);
1578		return root;
1579	}
1580
1581	root = btrfs_read_fs_root(fs_info->tree_root, location);
1582	if (IS_ERR(root))
1583		return root;
1584
1585	if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1586		ret = -ENOENT;
1587		goto fail;
1588	}
1589
1590	ret = btrfs_init_fs_root(root);
1591	if (ret)
1592		goto fail;
1593
1594	path = btrfs_alloc_path();
1595	if (!path) {
1596		ret = -ENOMEM;
1597		goto fail;
1598	}
1599	key.objectid = BTRFS_ORPHAN_OBJECTID;
1600	key.type = BTRFS_ORPHAN_ITEM_KEY;
1601	key.offset = location->objectid;
1602
1603	ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
1604	btrfs_free_path(path);
1605	if (ret < 0)
1606		goto fail;
1607	if (ret == 0)
1608		set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state);
1609
1610	ret = btrfs_insert_fs_root(fs_info, root);
1611	if (ret) {
1612		if (ret == -EEXIST) {
1613			btrfs_free_fs_root(root);
1614			goto again;
1615		}
1616		goto fail;
1617	}
1618	return root;
1619fail:
1620	btrfs_free_fs_root(root);
1621	return ERR_PTR(ret);
1622}
1623
1624static int btrfs_congested_fn(void *congested_data, int bdi_bits)
1625{
1626	struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
1627	int ret = 0;
1628	struct btrfs_device *device;
1629	struct backing_dev_info *bdi;
1630
1631	rcu_read_lock();
1632	list_for_each_entry_rcu(device, &info->fs_devices->devices, dev_list) {
1633		if (!device->bdev)
1634			continue;
1635		bdi = device->bdev->bd_bdi;
1636		if (bdi_congested(bdi, bdi_bits)) {
1637			ret = 1;
1638			break;
1639		}
1640	}
1641	rcu_read_unlock();
1642	return ret;
1643}
1644
1645/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1646 * called by the kthread helper functions to finally call the bio end_io
1647 * functions.  This is where read checksum verification actually happens
1648 */
1649static void end_workqueue_fn(struct btrfs_work *work)
1650{
1651	struct bio *bio;
1652	struct btrfs_end_io_wq *end_io_wq;
 
1653
1654	end_io_wq = container_of(work, struct btrfs_end_io_wq, work);
1655	bio = end_io_wq->bio;
1656
1657	bio->bi_status = end_io_wq->status;
1658	bio->bi_private = end_io_wq->private;
1659	bio->bi_end_io = end_io_wq->end_io;
1660	kmem_cache_free(btrfs_end_io_wq_cache, end_io_wq);
1661	bio_endio(bio);
1662}
1663
1664static int cleaner_kthread(void *arg)
1665{
1666	struct btrfs_root *root = arg;
1667	struct btrfs_fs_info *fs_info = root->fs_info;
1668	int again;
1669
1670	while (1) {
1671		again = 0;
1672
1673		set_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1674
1675		/* Make the cleaner go to sleep early. */
1676		if (btrfs_need_cleaner_sleep(fs_info))
1677			goto sleep;
1678
1679		/*
1680		 * Do not do anything if we might cause open_ctree() to block
1681		 * before we have finished mounting the filesystem.
1682		 */
1683		if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags))
1684			goto sleep;
1685
1686		if (!mutex_trylock(&fs_info->cleaner_mutex))
1687			goto sleep;
1688
1689		/*
1690		 * Avoid the problem that we change the status of the fs
1691		 * during the above check and trylock.
1692		 */
1693		if (btrfs_need_cleaner_sleep(fs_info)) {
1694			mutex_unlock(&fs_info->cleaner_mutex);
1695			goto sleep;
1696		}
1697
1698		btrfs_run_delayed_iputs(fs_info);
1699
1700		again = btrfs_clean_one_deleted_snapshot(root);
1701		mutex_unlock(&fs_info->cleaner_mutex);
1702
1703		/*
1704		 * The defragger has dealt with the R/O remount and umount,
1705		 * needn't do anything special here.
1706		 */
1707		btrfs_run_defrag_inodes(fs_info);
1708
1709		/*
1710		 * Acquires fs_info->delete_unused_bgs_mutex to avoid racing
1711		 * with relocation (btrfs_relocate_chunk) and relocation
1712		 * acquires fs_info->cleaner_mutex (btrfs_relocate_block_group)
1713		 * after acquiring fs_info->delete_unused_bgs_mutex. So we
1714		 * can't hold, nor need to, fs_info->cleaner_mutex when deleting
1715		 * unused block groups.
1716		 */
1717		btrfs_delete_unused_bgs(fs_info);
1718sleep:
1719		clear_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags);
1720		if (kthread_should_park())
1721			kthread_parkme();
1722		if (kthread_should_stop())
1723			return 0;
1724		if (!again) {
1725			set_current_state(TASK_INTERRUPTIBLE);
1726			schedule();
 
1727			__set_current_state(TASK_RUNNING);
1728		}
1729	}
 
1730}
1731
1732static int transaction_kthread(void *arg)
1733{
1734	struct btrfs_root *root = arg;
1735	struct btrfs_fs_info *fs_info = root->fs_info;
1736	struct btrfs_trans_handle *trans;
1737	struct btrfs_transaction *cur;
1738	u64 transid;
1739	time64_t now;
1740	unsigned long delay;
1741	bool cannot_commit;
1742
1743	do {
1744		cannot_commit = false;
1745		delay = HZ * fs_info->commit_interval;
1746		mutex_lock(&fs_info->transaction_kthread_mutex);
1747
1748		spin_lock(&fs_info->trans_lock);
1749		cur = fs_info->running_transaction;
1750		if (!cur) {
1751			spin_unlock(&fs_info->trans_lock);
1752			goto sleep;
1753		}
1754
1755		now = ktime_get_seconds();
1756		if (cur->state < TRANS_STATE_BLOCKED &&
1757		    !test_bit(BTRFS_FS_NEED_ASYNC_COMMIT, &fs_info->flags) &&
1758		    (now < cur->start_time ||
1759		     now - cur->start_time < fs_info->commit_interval)) {
1760			spin_unlock(&fs_info->trans_lock);
1761			delay = HZ * 5;
1762			goto sleep;
1763		}
1764		transid = cur->transid;
1765		spin_unlock(&fs_info->trans_lock);
1766
1767		/* If the file system is aborted, this will always fail. */
1768		trans = btrfs_attach_transaction(root);
1769		if (IS_ERR(trans)) {
1770			if (PTR_ERR(trans) != -ENOENT)
1771				cannot_commit = true;
1772			goto sleep;
1773		}
1774		if (transid == trans->transid) {
1775			btrfs_commit_transaction(trans);
1776		} else {
1777			btrfs_end_transaction(trans);
1778		}
1779sleep:
1780		wake_up_process(fs_info->cleaner_kthread);
1781		mutex_unlock(&fs_info->transaction_kthread_mutex);
1782
1783		if (unlikely(test_bit(BTRFS_FS_STATE_ERROR,
1784				      &fs_info->fs_state)))
1785			btrfs_cleanup_transaction(fs_info);
1786		if (!kthread_should_stop() &&
1787				(!btrfs_transaction_blocked(fs_info) ||
1788				 cannot_commit))
1789			schedule_timeout_interruptible(delay);
 
 
 
 
1790	} while (!kthread_should_stop());
1791	return 0;
1792}
1793
1794/*
1795 * this will find the highest generation in the array of
1796 * root backups.  The index of the highest array is returned,
1797 * or -1 if we can't find anything.
1798 *
1799 * We check to make sure the array is valid by comparing the
1800 * generation of the latest  root in the array with the generation
1801 * in the super block.  If they don't match we pitch it.
1802 */
1803static int find_newest_super_backup(struct btrfs_fs_info *info, u64 newest_gen)
1804{
1805	u64 cur;
1806	int newest_index = -1;
1807	struct btrfs_root_backup *root_backup;
1808	int i;
1809
1810	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
1811		root_backup = info->super_copy->super_roots + i;
1812		cur = btrfs_backup_tree_root_gen(root_backup);
1813		if (cur == newest_gen)
1814			newest_index = i;
1815	}
1816
1817	/* check to see if we actually wrapped around */
1818	if (newest_index == BTRFS_NUM_BACKUP_ROOTS - 1) {
1819		root_backup = info->super_copy->super_roots;
1820		cur = btrfs_backup_tree_root_gen(root_backup);
1821		if (cur == newest_gen)
1822			newest_index = 0;
1823	}
1824	return newest_index;
1825}
1826
1827
1828/*
1829 * find the oldest backup so we know where to store new entries
1830 * in the backup array.  This will set the backup_root_index
1831 * field in the fs_info struct
1832 */
1833static void find_oldest_super_backup(struct btrfs_fs_info *info,
1834				     u64 newest_gen)
1835{
1836	int newest_index = -1;
1837
1838	newest_index = find_newest_super_backup(info, newest_gen);
1839	/* if there was garbage in there, just move along */
1840	if (newest_index == -1) {
1841		info->backup_root_index = 0;
1842	} else {
1843		info->backup_root_index = (newest_index + 1) % BTRFS_NUM_BACKUP_ROOTS;
1844	}
1845}
1846
1847/*
1848 * copy all the root pointers into the super backup array.
1849 * this will bump the backup pointer by one when it is
1850 * done
1851 */
1852static void backup_super_roots(struct btrfs_fs_info *info)
1853{
1854	int next_backup;
1855	struct btrfs_root_backup *root_backup;
1856	int last_backup;
1857
1858	next_backup = info->backup_root_index;
1859	last_backup = (next_backup + BTRFS_NUM_BACKUP_ROOTS - 1) %
1860		BTRFS_NUM_BACKUP_ROOTS;
1861
1862	/*
1863	 * just overwrite the last backup if we're at the same generation
1864	 * this happens only at umount
1865	 */
1866	root_backup = info->super_for_commit->super_roots + last_backup;
1867	if (btrfs_backup_tree_root_gen(root_backup) ==
1868	    btrfs_header_generation(info->tree_root->node))
1869		next_backup = last_backup;
1870
1871	root_backup = info->super_for_commit->super_roots + next_backup;
1872
1873	/*
1874	 * make sure all of our padding and empty slots get zero filled
1875	 * regardless of which ones we use today
1876	 */
1877	memset(root_backup, 0, sizeof(*root_backup));
1878
1879	info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
1880
1881	btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
1882	btrfs_set_backup_tree_root_gen(root_backup,
1883			       btrfs_header_generation(info->tree_root->node));
1884
1885	btrfs_set_backup_tree_root_level(root_backup,
1886			       btrfs_header_level(info->tree_root->node));
1887
1888	btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
1889	btrfs_set_backup_chunk_root_gen(root_backup,
1890			       btrfs_header_generation(info->chunk_root->node));
1891	btrfs_set_backup_chunk_root_level(root_backup,
1892			       btrfs_header_level(info->chunk_root->node));
1893
1894	btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start);
1895	btrfs_set_backup_extent_root_gen(root_backup,
1896			       btrfs_header_generation(info->extent_root->node));
1897	btrfs_set_backup_extent_root_level(root_backup,
1898			       btrfs_header_level(info->extent_root->node));
1899
1900	/*
1901	 * we might commit during log recovery, which happens before we set
1902	 * the fs_root.  Make sure it is valid before we fill it in.
1903	 */
1904	if (info->fs_root && info->fs_root->node) {
1905		btrfs_set_backup_fs_root(root_backup,
1906					 info->fs_root->node->start);
1907		btrfs_set_backup_fs_root_gen(root_backup,
1908			       btrfs_header_generation(info->fs_root->node));
1909		btrfs_set_backup_fs_root_level(root_backup,
1910			       btrfs_header_level(info->fs_root->node));
1911	}
1912
1913	btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
1914	btrfs_set_backup_dev_root_gen(root_backup,
1915			       btrfs_header_generation(info->dev_root->node));
1916	btrfs_set_backup_dev_root_level(root_backup,
1917				       btrfs_header_level(info->dev_root->node));
1918
1919	btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start);
1920	btrfs_set_backup_csum_root_gen(root_backup,
1921			       btrfs_header_generation(info->csum_root->node));
1922	btrfs_set_backup_csum_root_level(root_backup,
1923			       btrfs_header_level(info->csum_root->node));
1924
1925	btrfs_set_backup_total_bytes(root_backup,
1926			     btrfs_super_total_bytes(info->super_copy));
1927	btrfs_set_backup_bytes_used(root_backup,
1928			     btrfs_super_bytes_used(info->super_copy));
1929	btrfs_set_backup_num_devices(root_backup,
1930			     btrfs_super_num_devices(info->super_copy));
1931
1932	/*
1933	 * if we don't copy this out to the super_copy, it won't get remembered
1934	 * for the next commit
1935	 */
1936	memcpy(&info->super_copy->super_roots,
1937	       &info->super_for_commit->super_roots,
1938	       sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
1939}
1940
1941/*
1942 * this copies info out of the root backup array and back into
1943 * the in-memory super block.  It is meant to help iterate through
1944 * the array, so you send it the number of backups you've already
1945 * tried and the last backup index you used.
1946 *
1947 * this returns -1 when it has tried all the backups
1948 */
1949static noinline int next_root_backup(struct btrfs_fs_info *info,
1950				     struct btrfs_super_block *super,
1951				     int *num_backups_tried, int *backup_index)
1952{
1953	struct btrfs_root_backup *root_backup;
1954	int newest = *backup_index;
1955
1956	if (*num_backups_tried == 0) {
1957		u64 gen = btrfs_super_generation(super);
1958
1959		newest = find_newest_super_backup(info, gen);
1960		if (newest == -1)
1961			return -1;
1962
1963		*backup_index = newest;
1964		*num_backups_tried = 1;
1965	} else if (*num_backups_tried == BTRFS_NUM_BACKUP_ROOTS) {
1966		/* we've tried all the backups, all done */
1967		return -1;
1968	} else {
1969		/* jump to the next oldest backup */
1970		newest = (*backup_index + BTRFS_NUM_BACKUP_ROOTS - 1) %
1971			BTRFS_NUM_BACKUP_ROOTS;
1972		*backup_index = newest;
1973		*num_backups_tried += 1;
1974	}
1975	root_backup = super->super_roots + newest;
1976
1977	btrfs_set_super_generation(super,
1978				   btrfs_backup_tree_root_gen(root_backup));
1979	btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
1980	btrfs_set_super_root_level(super,
1981				   btrfs_backup_tree_root_level(root_backup));
1982	btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
1983
1984	/*
1985	 * fixme: the total bytes and num_devices need to match or we should
1986	 * need a fsck
1987	 */
1988	btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
1989	btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
1990	return 0;
1991}
1992
1993/* helper to cleanup workers */
1994static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
1995{
1996	btrfs_destroy_workqueue(fs_info->fixup_workers);
1997	btrfs_destroy_workqueue(fs_info->delalloc_workers);
1998	btrfs_destroy_workqueue(fs_info->workers);
1999	btrfs_destroy_workqueue(fs_info->endio_workers);
 
2000	btrfs_destroy_workqueue(fs_info->endio_raid56_workers);
2001	btrfs_destroy_workqueue(fs_info->endio_repair_workers);
2002	btrfs_destroy_workqueue(fs_info->rmw_workers);
 
2003	btrfs_destroy_workqueue(fs_info->endio_write_workers);
2004	btrfs_destroy_workqueue(fs_info->endio_freespace_worker);
2005	btrfs_destroy_workqueue(fs_info->submit_workers);
2006	btrfs_destroy_workqueue(fs_info->delayed_workers);
2007	btrfs_destroy_workqueue(fs_info->caching_workers);
2008	btrfs_destroy_workqueue(fs_info->readahead_workers);
2009	btrfs_destroy_workqueue(fs_info->flush_workers);
2010	btrfs_destroy_workqueue(fs_info->qgroup_rescan_workers);
2011	/*
2012	 * Now that all other work queues are destroyed, we can safely destroy
2013	 * the queues used for metadata I/O, since tasks from those other work
2014	 * queues can do metadata I/O operations.
2015	 */
2016	btrfs_destroy_workqueue(fs_info->endio_meta_workers);
2017	btrfs_destroy_workqueue(fs_info->endio_meta_write_workers);
2018}
2019
2020static void free_root_extent_buffers(struct btrfs_root *root)
2021{
2022	if (root) {
2023		free_extent_buffer(root->node);
2024		free_extent_buffer(root->commit_root);
2025		root->node = NULL;
2026		root->commit_root = NULL;
2027	}
2028}
2029
2030/* helper to cleanup tree roots */
2031static void free_root_pointers(struct btrfs_fs_info *info, int chunk_root)
2032{
2033	free_root_extent_buffers(info->tree_root);
2034
2035	free_root_extent_buffers(info->dev_root);
2036	free_root_extent_buffers(info->extent_root);
2037	free_root_extent_buffers(info->csum_root);
2038	free_root_extent_buffers(info->quota_root);
2039	free_root_extent_buffers(info->uuid_root);
2040	if (chunk_root)
2041		free_root_extent_buffers(info->chunk_root);
2042	free_root_extent_buffers(info->free_space_root);
2043}
2044
2045void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info)
2046{
2047	int ret;
2048	struct btrfs_root *gang[8];
2049	int i;
2050
2051	while (!list_empty(&fs_info->dead_roots)) {
2052		gang[0] = list_entry(fs_info->dead_roots.next,
2053				     struct btrfs_root, root_list);
2054		list_del(&gang[0]->root_list);
2055
2056		if (test_bit(BTRFS_ROOT_IN_RADIX, &gang[0]->state)) {
2057			btrfs_drop_and_free_fs_root(fs_info, gang[0]);
2058		} else {
2059			free_extent_buffer(gang[0]->node);
2060			free_extent_buffer(gang[0]->commit_root);
2061			btrfs_put_fs_root(gang[0]);
2062		}
2063	}
2064
2065	while (1) {
2066		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2067					     (void **)gang, 0,
2068					     ARRAY_SIZE(gang));
2069		if (!ret)
2070			break;
2071		for (i = 0; i < ret; i++)
2072			btrfs_drop_and_free_fs_root(fs_info, gang[i]);
2073	}
2074
2075	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
2076		btrfs_free_log_root_tree(NULL, fs_info);
2077		btrfs_destroy_pinned_extent(fs_info, fs_info->pinned_extents);
 
2078	}
2079}
2080
2081static void btrfs_init_scrub(struct btrfs_fs_info *fs_info)
2082{
2083	mutex_init(&fs_info->scrub_lock);
2084	atomic_set(&fs_info->scrubs_running, 0);
2085	atomic_set(&fs_info->scrub_pause_req, 0);
2086	atomic_set(&fs_info->scrubs_paused, 0);
2087	atomic_set(&fs_info->scrub_cancel_req, 0);
2088	init_waitqueue_head(&fs_info->scrub_pause_wait);
2089	refcount_set(&fs_info->scrub_workers_refcnt, 0);
2090}
2091
2092static void btrfs_init_balance(struct btrfs_fs_info *fs_info)
2093{
2094	spin_lock_init(&fs_info->balance_lock);
2095	mutex_init(&fs_info->balance_mutex);
2096	atomic_set(&fs_info->balance_pause_req, 0);
2097	atomic_set(&fs_info->balance_cancel_req, 0);
2098	fs_info->balance_ctl = NULL;
2099	init_waitqueue_head(&fs_info->balance_wait_q);
2100}
2101
2102static void btrfs_init_btree_inode(struct btrfs_fs_info *fs_info)
2103{
2104	struct inode *inode = fs_info->btree_inode;
2105
2106	inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
2107	set_nlink(inode, 1);
2108	/*
2109	 * we set the i_size on the btree inode to the max possible int.
2110	 * the real end of the address space is determined by all of
2111	 * the devices in the system
2112	 */
2113	inode->i_size = OFFSET_MAX;
2114	inode->i_mapping->a_ops = &btree_aops;
2115
2116	RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
2117	extent_io_tree_init(fs_info, &BTRFS_I(inode)->io_tree,
2118			    IO_TREE_INODE_IO, inode);
2119	BTRFS_I(inode)->io_tree.track_uptodate = false;
2120	extent_map_tree_init(&BTRFS_I(inode)->extent_tree);
2121
2122	BTRFS_I(inode)->io_tree.ops = &btree_extent_io_ops;
2123
2124	BTRFS_I(inode)->root = fs_info->tree_root;
2125	memset(&BTRFS_I(inode)->location, 0, sizeof(struct btrfs_key));
2126	set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
2127	btrfs_insert_inode_hash(inode);
2128}
2129
2130static void btrfs_init_dev_replace_locks(struct btrfs_fs_info *fs_info)
2131{
2132	mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount);
2133	init_rwsem(&fs_info->dev_replace.rwsem);
2134	init_waitqueue_head(&fs_info->dev_replace.replace_wait);
2135}
2136
2137static void btrfs_init_qgroup(struct btrfs_fs_info *fs_info)
2138{
2139	spin_lock_init(&fs_info->qgroup_lock);
2140	mutex_init(&fs_info->qgroup_ioctl_lock);
2141	fs_info->qgroup_tree = RB_ROOT;
2142	INIT_LIST_HEAD(&fs_info->dirty_qgroups);
2143	fs_info->qgroup_seq = 1;
2144	fs_info->qgroup_ulist = NULL;
2145	fs_info->qgroup_rescan_running = false;
2146	mutex_init(&fs_info->qgroup_rescan_lock);
2147}
2148
2149static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info,
2150		struct btrfs_fs_devices *fs_devices)
2151{
2152	u32 max_active = fs_info->thread_pool_size;
2153	unsigned int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND;
2154
2155	fs_info->workers =
2156		btrfs_alloc_workqueue(fs_info, "worker",
2157				      flags | WQ_HIGHPRI, max_active, 16);
2158
2159	fs_info->delalloc_workers =
2160		btrfs_alloc_workqueue(fs_info, "delalloc",
2161				      flags, max_active, 2);
2162
2163	fs_info->flush_workers =
2164		btrfs_alloc_workqueue(fs_info, "flush_delalloc",
2165				      flags, max_active, 0);
2166
2167	fs_info->caching_workers =
2168		btrfs_alloc_workqueue(fs_info, "cache", flags, max_active, 0);
2169
2170	/*
2171	 * a higher idle thresh on the submit workers makes it much more
2172	 * likely that bios will be send down in a sane order to the
2173	 * devices
2174	 */
2175	fs_info->submit_workers =
2176		btrfs_alloc_workqueue(fs_info, "submit", flags,
2177				      min_t(u64, fs_devices->num_devices,
2178					    max_active), 64);
2179
2180	fs_info->fixup_workers =
2181		btrfs_alloc_workqueue(fs_info, "fixup", flags, 1, 0);
2182
2183	/*
2184	 * endios are largely parallel and should have a very
2185	 * low idle thresh
2186	 */
2187	fs_info->endio_workers =
2188		btrfs_alloc_workqueue(fs_info, "endio", flags, max_active, 4);
2189	fs_info->endio_meta_workers =
2190		btrfs_alloc_workqueue(fs_info, "endio-meta", flags,
2191				      max_active, 4);
2192	fs_info->endio_meta_write_workers =
2193		btrfs_alloc_workqueue(fs_info, "endio-meta-write", flags,
2194				      max_active, 2);
2195	fs_info->endio_raid56_workers =
2196		btrfs_alloc_workqueue(fs_info, "endio-raid56", flags,
2197				      max_active, 4);
2198	fs_info->endio_repair_workers =
2199		btrfs_alloc_workqueue(fs_info, "endio-repair", flags, 1, 0);
2200	fs_info->rmw_workers =
2201		btrfs_alloc_workqueue(fs_info, "rmw", flags, max_active, 2);
2202	fs_info->endio_write_workers =
2203		btrfs_alloc_workqueue(fs_info, "endio-write", flags,
2204				      max_active, 2);
2205	fs_info->endio_freespace_worker =
2206		btrfs_alloc_workqueue(fs_info, "freespace-write", flags,
2207				      max_active, 0);
2208	fs_info->delayed_workers =
2209		btrfs_alloc_workqueue(fs_info, "delayed-meta", flags,
2210				      max_active, 0);
2211	fs_info->readahead_workers =
2212		btrfs_alloc_workqueue(fs_info, "readahead", flags,
2213				      max_active, 2);
2214	fs_info->qgroup_rescan_workers =
2215		btrfs_alloc_workqueue(fs_info, "qgroup-rescan", flags, 1, 0);
2216
2217	if (!(fs_info->workers && fs_info->delalloc_workers &&
2218	      fs_info->submit_workers && fs_info->flush_workers &&
2219	      fs_info->endio_workers && fs_info->endio_meta_workers &&
2220	      fs_info->endio_meta_write_workers &&
2221	      fs_info->endio_repair_workers &&
2222	      fs_info->endio_write_workers && fs_info->endio_raid56_workers &&
2223	      fs_info->endio_freespace_worker && fs_info->rmw_workers &&
2224	      fs_info->caching_workers && fs_info->readahead_workers &&
2225	      fs_info->fixup_workers && fs_info->delayed_workers &&
2226	      fs_info->qgroup_rescan_workers)) {
2227		return -ENOMEM;
2228	}
2229
2230	return 0;
2231}
2232
2233static int btrfs_init_csum_hash(struct btrfs_fs_info *fs_info, u16 csum_type)
2234{
2235	struct crypto_shash *csum_shash;
2236	const char *csum_name = btrfs_super_csum_name(csum_type);
2237
2238	csum_shash = crypto_alloc_shash(csum_name, 0, 0);
2239
2240	if (IS_ERR(csum_shash)) {
2241		btrfs_err(fs_info, "error allocating %s hash for checksum",
2242			  csum_name);
2243		return PTR_ERR(csum_shash);
2244	}
2245
2246	fs_info->csum_shash = csum_shash;
2247
2248	return 0;
2249}
2250
2251static void btrfs_free_csum_hash(struct btrfs_fs_info *fs_info)
2252{
2253	crypto_free_shash(fs_info->csum_shash);
2254}
2255
2256static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
2257			    struct btrfs_fs_devices *fs_devices)
2258{
2259	int ret;
2260	struct btrfs_root *log_tree_root;
2261	struct btrfs_super_block *disk_super = fs_info->super_copy;
2262	u64 bytenr = btrfs_super_log_root(disk_super);
2263	int level = btrfs_super_log_root_level(disk_super);
2264
2265	if (fs_devices->rw_devices == 0) {
2266		btrfs_warn(fs_info, "log replay required on RO media");
2267		return -EIO;
2268	}
2269
2270	log_tree_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
2271	if (!log_tree_root)
2272		return -ENOMEM;
2273
2274	__setup_root(log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
2275
2276	log_tree_root->node = read_tree_block(fs_info, bytenr,
2277					      fs_info->generation + 1,
2278					      level, NULL);
2279	if (IS_ERR(log_tree_root->node)) {
2280		btrfs_warn(fs_info, "failed to read log tree");
2281		ret = PTR_ERR(log_tree_root->node);
2282		kfree(log_tree_root);
2283		return ret;
2284	} else if (!extent_buffer_uptodate(log_tree_root->node)) {
2285		btrfs_err(fs_info, "failed to read log tree");
2286		free_extent_buffer(log_tree_root->node);
2287		kfree(log_tree_root);
2288		return -EIO;
2289	}
2290	/* returns with log_tree_root freed on success */
2291	ret = btrfs_recover_log_trees(log_tree_root);
2292	if (ret) {
2293		btrfs_handle_fs_error(fs_info, ret,
2294				      "Failed to recover log tree");
2295		free_extent_buffer(log_tree_root->node);
2296		kfree(log_tree_root);
2297		return ret;
2298	}
2299
2300	if (sb_rdonly(fs_info->sb)) {
2301		ret = btrfs_commit_super(fs_info);
2302		if (ret)
2303			return ret;
2304	}
2305
2306	return 0;
2307}
2308
2309static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
2310{
2311	struct btrfs_root *tree_root = fs_info->tree_root;
2312	struct btrfs_root *root;
2313	struct btrfs_key location;
2314	int ret;
2315
2316	BUG_ON(!fs_info->tree_root);
2317
2318	location.objectid = BTRFS_EXTENT_TREE_OBJECTID;
2319	location.type = BTRFS_ROOT_ITEM_KEY;
2320	location.offset = 0;
2321
2322	root = btrfs_read_tree_root(tree_root, &location);
2323	if (IS_ERR(root)) {
2324		ret = PTR_ERR(root);
2325		goto out;
2326	}
2327	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2328	fs_info->extent_root = root;
2329
2330	location.objectid = BTRFS_DEV_TREE_OBJECTID;
2331	root = btrfs_read_tree_root(tree_root, &location);
2332	if (IS_ERR(root)) {
2333		ret = PTR_ERR(root);
2334		goto out;
2335	}
2336	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2337	fs_info->dev_root = root;
2338	btrfs_init_devices_late(fs_info);
2339
2340	location.objectid = BTRFS_CSUM_TREE_OBJECTID;
2341	root = btrfs_read_tree_root(tree_root, &location);
2342	if (IS_ERR(root)) {
2343		ret = PTR_ERR(root);
2344		goto out;
2345	}
2346	set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2347	fs_info->csum_root = root;
2348
2349	location.objectid = BTRFS_QUOTA_TREE_OBJECTID;
2350	root = btrfs_read_tree_root(tree_root, &location);
2351	if (!IS_ERR(root)) {
2352		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2353		set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
2354		fs_info->quota_root = root;
2355	}
2356
2357	location.objectid = BTRFS_UUID_TREE_OBJECTID;
2358	root = btrfs_read_tree_root(tree_root, &location);
2359	if (IS_ERR(root)) {
2360		ret = PTR_ERR(root);
2361		if (ret != -ENOENT)
2362			goto out;
2363	} else {
2364		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2365		fs_info->uuid_root = root;
2366	}
2367
2368	if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
2369		location.objectid = BTRFS_FREE_SPACE_TREE_OBJECTID;
2370		root = btrfs_read_tree_root(tree_root, &location);
2371		if (IS_ERR(root)) {
2372			ret = PTR_ERR(root);
2373			goto out;
2374		}
2375		set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
2376		fs_info->free_space_root = root;
2377	}
2378
2379	return 0;
2380out:
2381	btrfs_warn(fs_info, "failed to read root (objectid=%llu): %d",
2382		   location.objectid, ret);
2383	return ret;
2384}
2385
2386/*
2387 * Real super block validation
2388 * NOTE: super csum type and incompat features will not be checked here.
2389 *
2390 * @sb:		super block to check
2391 * @mirror_num:	the super block number to check its bytenr:
2392 * 		0	the primary (1st) sb
2393 * 		1, 2	2nd and 3rd backup copy
2394 * 	       -1	skip bytenr check
2395 */
2396static int validate_super(struct btrfs_fs_info *fs_info,
2397			    struct btrfs_super_block *sb, int mirror_num)
2398{
2399	u64 nodesize = btrfs_super_nodesize(sb);
2400	u64 sectorsize = btrfs_super_sectorsize(sb);
2401	int ret = 0;
2402
2403	if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
2404		btrfs_err(fs_info, "no valid FS found");
2405		ret = -EINVAL;
2406	}
2407	if (btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP) {
2408		btrfs_err(fs_info, "unrecognized or unsupported super flag: %llu",
2409				btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);
2410		ret = -EINVAL;
2411	}
2412	if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
2413		btrfs_err(fs_info, "tree_root level too big: %d >= %d",
2414				btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
2415		ret = -EINVAL;
2416	}
2417	if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
2418		btrfs_err(fs_info, "chunk_root level too big: %d >= %d",
2419				btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
2420		ret = -EINVAL;
2421	}
2422	if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
2423		btrfs_err(fs_info, "log_root level too big: %d >= %d",
2424				btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
2425		ret = -EINVAL;
2426	}
2427
2428	/*
2429	 * Check sectorsize and nodesize first, other check will need it.
2430	 * Check all possible sectorsize(4K, 8K, 16K, 32K, 64K) here.
2431	 */
2432	if (!is_power_of_2(sectorsize) || sectorsize < 4096 ||
2433	    sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2434		btrfs_err(fs_info, "invalid sectorsize %llu", sectorsize);
2435		ret = -EINVAL;
2436	}
2437	/* Only PAGE SIZE is supported yet */
2438	if (sectorsize != PAGE_SIZE) {
2439		btrfs_err(fs_info,
2440			"sectorsize %llu not supported yet, only support %lu",
2441			sectorsize, PAGE_SIZE);
2442		ret = -EINVAL;
2443	}
2444	if (!is_power_of_2(nodesize) || nodesize < sectorsize ||
2445	    nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2446		btrfs_err(fs_info, "invalid nodesize %llu", nodesize);
2447		ret = -EINVAL;
2448	}
2449	if (nodesize != le32_to_cpu(sb->__unused_leafsize)) {
2450		btrfs_err(fs_info, "invalid leafsize %u, should be %llu",
2451			  le32_to_cpu(sb->__unused_leafsize), nodesize);
2452		ret = -EINVAL;
2453	}
2454
2455	/* Root alignment check */
2456	if (!IS_ALIGNED(btrfs_super_root(sb), sectorsize)) {
2457		btrfs_warn(fs_info, "tree_root block unaligned: %llu",
2458			   btrfs_super_root(sb));
2459		ret = -EINVAL;
2460	}
2461	if (!IS_ALIGNED(btrfs_super_chunk_root(sb), sectorsize)) {
2462		btrfs_warn(fs_info, "chunk_root block unaligned: %llu",
2463			   btrfs_super_chunk_root(sb));
2464		ret = -EINVAL;
2465	}
2466	if (!IS_ALIGNED(btrfs_super_log_root(sb), sectorsize)) {
2467		btrfs_warn(fs_info, "log_root block unaligned: %llu",
2468			   btrfs_super_log_root(sb));
2469		ret = -EINVAL;
2470	}
2471
2472	if (memcmp(fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid,
2473		   BTRFS_FSID_SIZE) != 0) {
2474		btrfs_err(fs_info,
2475			"dev_item UUID does not match metadata fsid: %pU != %pU",
2476			fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid);
2477		ret = -EINVAL;
2478	}
2479
2480	/*
2481	 * Hint to catch really bogus numbers, bitflips or so, more exact checks are
2482	 * done later
2483	 */
2484	if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) {
2485		btrfs_err(fs_info, "bytes_used is too small %llu",
2486			  btrfs_super_bytes_used(sb));
2487		ret = -EINVAL;
2488	}
2489	if (!is_power_of_2(btrfs_super_stripesize(sb))) {
2490		btrfs_err(fs_info, "invalid stripesize %u",
2491			  btrfs_super_stripesize(sb));
2492		ret = -EINVAL;
2493	}
2494	if (btrfs_super_num_devices(sb) > (1UL << 31))
2495		btrfs_warn(fs_info, "suspicious number of devices: %llu",
2496			   btrfs_super_num_devices(sb));
2497	if (btrfs_super_num_devices(sb) == 0) {
2498		btrfs_err(fs_info, "number of devices is 0");
2499		ret = -EINVAL;
2500	}
2501
2502	if (mirror_num >= 0 &&
2503	    btrfs_super_bytenr(sb) != btrfs_sb_offset(mirror_num)) {
2504		btrfs_err(fs_info, "super offset mismatch %llu != %u",
2505			  btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET);
2506		ret = -EINVAL;
2507	}
2508
2509	/*
2510	 * Obvious sys_chunk_array corruptions, it must hold at least one key
2511	 * and one chunk
2512	 */
2513	if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
2514		btrfs_err(fs_info, "system chunk array too big %u > %u",
2515			  btrfs_super_sys_array_size(sb),
2516			  BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
2517		ret = -EINVAL;
2518	}
2519	if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
2520			+ sizeof(struct btrfs_chunk)) {
2521		btrfs_err(fs_info, "system chunk array too small %u < %zu",
2522			  btrfs_super_sys_array_size(sb),
2523			  sizeof(struct btrfs_disk_key)
2524			  + sizeof(struct btrfs_chunk));
2525		ret = -EINVAL;
2526	}
2527
2528	/*
2529	 * The generation is a global counter, we'll trust it more than the others
2530	 * but it's still possible that it's the one that's wrong.
2531	 */
2532	if (btrfs_super_generation(sb) < btrfs_super_chunk_root_generation(sb))
2533		btrfs_warn(fs_info,
2534			"suspicious: generation < chunk_root_generation: %llu < %llu",
2535			btrfs_super_generation(sb),
2536			btrfs_super_chunk_root_generation(sb));
2537	if (btrfs_super_generation(sb) < btrfs_super_cache_generation(sb)
2538	    && btrfs_super_cache_generation(sb) != (u64)-1)
2539		btrfs_warn(fs_info,
2540			"suspicious: generation < cache_generation: %llu < %llu",
2541			btrfs_super_generation(sb),
2542			btrfs_super_cache_generation(sb));
2543
2544	return ret;
2545}
2546
2547/*
2548 * Validation of super block at mount time.
2549 * Some checks already done early at mount time, like csum type and incompat
2550 * flags will be skipped.
2551 */
2552static int btrfs_validate_mount_super(struct btrfs_fs_info *fs_info)
2553{
2554	return validate_super(fs_info, fs_info->super_copy, 0);
2555}
2556
2557/*
2558 * Validation of super block at write time.
2559 * Some checks like bytenr check will be skipped as their values will be
2560 * overwritten soon.
2561 * Extra checks like csum type and incompat flags will be done here.
2562 */
2563static int btrfs_validate_write_super(struct btrfs_fs_info *fs_info,
2564				      struct btrfs_super_block *sb)
2565{
2566	int ret;
2567
2568	ret = validate_super(fs_info, sb, -1);
2569	if (ret < 0)
2570		goto out;
2571	if (!btrfs_supported_super_csum(btrfs_super_csum_type(sb))) {
2572		ret = -EUCLEAN;
2573		btrfs_err(fs_info, "invalid csum type, has %u want %u",
2574			  btrfs_super_csum_type(sb), BTRFS_CSUM_TYPE_CRC32);
2575		goto out;
2576	}
2577	if (btrfs_super_incompat_flags(sb) & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
2578		ret = -EUCLEAN;
2579		btrfs_err(fs_info,
2580		"invalid incompat flags, has 0x%llx valid mask 0x%llx",
2581			  btrfs_super_incompat_flags(sb),
2582			  (unsigned long long)BTRFS_FEATURE_INCOMPAT_SUPP);
2583		goto out;
2584	}
2585out:
2586	if (ret < 0)
2587		btrfs_err(fs_info,
2588		"super block corruption detected before writing it to disk");
2589	return ret;
2590}
2591
2592int open_ctree(struct super_block *sb,
2593	       struct btrfs_fs_devices *fs_devices,
2594	       char *options)
2595{
2596	u32 sectorsize;
2597	u32 nodesize;
 
 
2598	u32 stripesize;
2599	u64 generation;
2600	u64 features;
2601	u16 csum_type;
2602	struct btrfs_key location;
2603	struct buffer_head *bh;
2604	struct btrfs_super_block *disk_super;
2605	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
2606	struct btrfs_root *tree_root;
 
 
2607	struct btrfs_root *chunk_root;
 
 
 
 
2608	int ret;
2609	int err = -EINVAL;
2610	int num_backups_tried = 0;
2611	int backup_index = 0;
2612	int clear_free_space_tree = 0;
2613	int level;
 
 
2614
2615	tree_root = fs_info->tree_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
2616	chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
2617	if (!tree_root || !chunk_root) {
2618		err = -ENOMEM;
2619		goto fail;
2620	}
2621
2622	ret = init_srcu_struct(&fs_info->subvol_srcu);
2623	if (ret) {
2624		err = ret;
2625		goto fail;
2626	}
2627
2628	ret = percpu_counter_init(&fs_info->dio_bytes, 0, GFP_KERNEL);
2629	if (ret) {
2630		err = ret;
2631		goto fail_srcu;
2632	}
2633
2634	ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0, GFP_KERNEL);
2635	if (ret) {
2636		err = ret;
2637		goto fail_dio_bytes;
2638	}
2639	fs_info->dirty_metadata_batch = PAGE_SIZE *
2640					(1 + ilog2(nr_cpu_ids));
2641
2642	ret = percpu_counter_init(&fs_info->delalloc_bytes, 0, GFP_KERNEL);
2643	if (ret) {
2644		err = ret;
2645		goto fail_dirty_metadata_bytes;
2646	}
2647
2648	ret = percpu_counter_init(&fs_info->dev_replace.bio_counter, 0,
2649			GFP_KERNEL);
2650	if (ret) {
2651		err = ret;
2652		goto fail_delalloc_bytes;
2653	}
2654
 
 
 
 
 
 
 
 
2655	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
2656	INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC);
2657	INIT_LIST_HEAD(&fs_info->trans_list);
2658	INIT_LIST_HEAD(&fs_info->dead_roots);
2659	INIT_LIST_HEAD(&fs_info->delayed_iputs);
2660	INIT_LIST_HEAD(&fs_info->delalloc_roots);
2661	INIT_LIST_HEAD(&fs_info->caching_block_groups);
2662	spin_lock_init(&fs_info->delalloc_root_lock);
2663	spin_lock_init(&fs_info->trans_lock);
2664	spin_lock_init(&fs_info->fs_roots_radix_lock);
2665	spin_lock_init(&fs_info->delayed_iput_lock);
2666	spin_lock_init(&fs_info->defrag_inodes_lock);
 
2667	spin_lock_init(&fs_info->tree_mod_seq_lock);
2668	spin_lock_init(&fs_info->super_lock);
2669	spin_lock_init(&fs_info->buffer_lock);
2670	spin_lock_init(&fs_info->unused_bgs_lock);
2671	rwlock_init(&fs_info->tree_mod_log_lock);
2672	mutex_init(&fs_info->unused_bg_unpin_mutex);
2673	mutex_init(&fs_info->delete_unused_bgs_mutex);
2674	mutex_init(&fs_info->reloc_mutex);
2675	mutex_init(&fs_info->delalloc_root_mutex);
2676	seqlock_init(&fs_info->profiles_lock);
2677
 
2678	INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
2679	INIT_LIST_HEAD(&fs_info->space_info);
2680	INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
2681	INIT_LIST_HEAD(&fs_info->unused_bgs);
2682	extent_map_tree_init(&fs_info->mapping_tree);
2683	btrfs_init_block_rsv(&fs_info->global_block_rsv,
2684			     BTRFS_BLOCK_RSV_GLOBAL);
 
 
2685	btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
2686	btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK);
2687	btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY);
2688	btrfs_init_block_rsv(&fs_info->delayed_block_rsv,
2689			     BTRFS_BLOCK_RSV_DELOPS);
2690	btrfs_init_block_rsv(&fs_info->delayed_refs_rsv,
2691			     BTRFS_BLOCK_RSV_DELREFS);
2692
2693	atomic_set(&fs_info->async_delalloc_pages, 0);
 
 
2694	atomic_set(&fs_info->defrag_running, 0);
2695	atomic_set(&fs_info->reada_works_cnt, 0);
2696	atomic_set(&fs_info->nr_delayed_iputs, 0);
2697	atomic64_set(&fs_info->tree_mod_seq, 0);
2698	fs_info->sb = sb;
2699	fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE;
2700	fs_info->metadata_ratio = 0;
2701	fs_info->defrag_inodes = RB_ROOT;
2702	atomic64_set(&fs_info->free_chunk_space, 0);
2703	fs_info->tree_mod_log = RB_ROOT;
2704	fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
2705	fs_info->avg_delayed_ref_runtime = NSEC_PER_SEC >> 6; /* div by 64 */
2706	/* readahead state */
2707	INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
2708	spin_lock_init(&fs_info->reada_lock);
2709	btrfs_init_ref_verify(fs_info);
2710
2711	fs_info->thread_pool_size = min_t(unsigned long,
2712					  num_online_cpus() + 2, 8);
2713
2714	INIT_LIST_HEAD(&fs_info->ordered_roots);
2715	spin_lock_init(&fs_info->ordered_root_lock);
2716
2717	fs_info->btree_inode = new_inode(sb);
2718	if (!fs_info->btree_inode) {
2719		err = -ENOMEM;
2720		goto fail_bio_counter;
2721	}
2722	mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
2723
2724	fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
2725					GFP_KERNEL);
2726	if (!fs_info->delayed_root) {
2727		err = -ENOMEM;
2728		goto fail_iput;
2729	}
2730	btrfs_init_delayed_root(fs_info->delayed_root);
2731
2732	btrfs_init_scrub(fs_info);
 
 
 
 
 
 
 
2733#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
2734	fs_info->check_integrity_print_mask = 0;
2735#endif
2736	btrfs_init_balance(fs_info);
2737	btrfs_init_async_reclaim_work(&fs_info->async_reclaim_work);
2738
2739	sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE;
2740	sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE);
 
 
 
 
 
2741
2742	btrfs_init_btree_inode(fs_info);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2743
2744	spin_lock_init(&fs_info->block_group_cache_lock);
2745	fs_info->block_group_cache_tree = RB_ROOT;
2746	fs_info->first_logical_byte = (u64)-1;
2747
2748	extent_io_tree_init(fs_info, &fs_info->freed_extents[0],
2749			    IO_TREE_FS_INFO_FREED_EXTENTS0, NULL);
2750	extent_io_tree_init(fs_info, &fs_info->freed_extents[1],
2751			    IO_TREE_FS_INFO_FREED_EXTENTS1, NULL);
2752	fs_info->pinned_extents = &fs_info->freed_extents[0];
2753	set_bit(BTRFS_FS_BARRIER, &fs_info->flags);
 
2754
2755	mutex_init(&fs_info->ordered_operations_mutex);
 
2756	mutex_init(&fs_info->tree_log_mutex);
2757	mutex_init(&fs_info->chunk_mutex);
2758	mutex_init(&fs_info->transaction_kthread_mutex);
2759	mutex_init(&fs_info->cleaner_mutex);
2760	mutex_init(&fs_info->ro_block_group_mutex);
2761	init_rwsem(&fs_info->commit_root_sem);
2762	init_rwsem(&fs_info->cleanup_work_sem);
2763	init_rwsem(&fs_info->subvol_sem);
2764	sema_init(&fs_info->uuid_tree_rescan_sem, 1);
 
 
 
 
 
2765
2766	btrfs_init_dev_replace_locks(fs_info);
2767	btrfs_init_qgroup(fs_info);
 
 
 
 
 
 
 
2768
2769	btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
2770	btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
2771
2772	init_waitqueue_head(&fs_info->transaction_throttle);
2773	init_waitqueue_head(&fs_info->transaction_wait);
2774	init_waitqueue_head(&fs_info->transaction_blocked_wait);
2775	init_waitqueue_head(&fs_info->async_submit_wait);
2776	init_waitqueue_head(&fs_info->delayed_iputs_wait);
2777
2778	/* Usable values until the real ones are cached from the superblock */
2779	fs_info->nodesize = 4096;
2780	fs_info->sectorsize = 4096;
2781	fs_info->stripesize = 4096;
2782
2783	spin_lock_init(&fs_info->swapfile_pins_lock);
2784	fs_info->swapfile_pins = RB_ROOT;
2785
2786	fs_info->send_in_progress = 0;
2787
2788	ret = btrfs_alloc_stripe_hash_table(fs_info);
2789	if (ret) {
2790		err = ret;
2791		goto fail_alloc;
2792	}
2793
2794	__setup_root(tree_root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
 
2795
2796	invalidate_bdev(fs_devices->latest_bdev);
2797
2798	/*
2799	 * Read super block and check the signature bytes only
2800	 */
2801	bh = btrfs_read_dev_super(fs_devices->latest_bdev);
2802	if (IS_ERR(bh)) {
2803		err = PTR_ERR(bh);
2804		goto fail_alloc;
2805	}
2806
2807	/*
2808	 * Verify the type first, if that or the the checksum value are
2809	 * corrupted, we'll find out
2810	 */
2811	csum_type = btrfs_super_csum_type((struct btrfs_super_block *)bh->b_data);
2812	if (!btrfs_supported_super_csum(csum_type)) {
2813		btrfs_err(fs_info, "unsupported checksum algorithm: %u",
2814			  csum_type);
2815		err = -EINVAL;
2816		brelse(bh);
2817		goto fail_alloc;
2818	}
2819
2820	ret = btrfs_init_csum_hash(fs_info, csum_type);
2821	if (ret) {
2822		err = ret;
2823		goto fail_alloc;
2824	}
2825
2826	/*
2827	 * We want to check superblock checksum, the type is stored inside.
2828	 * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k).
2829	 */
2830	if (btrfs_check_super_csum(fs_info, bh->b_data)) {
2831		btrfs_err(fs_info, "superblock checksum mismatch");
2832		err = -EINVAL;
2833		brelse(bh);
2834		goto fail_csum;
2835	}
2836
2837	/*
2838	 * super_copy is zeroed at allocation time and we never touch the
2839	 * following bytes up to INFO_SIZE, the checksum is calculated from
2840	 * the whole block of INFO_SIZE
2841	 */
2842	memcpy(fs_info->super_copy, bh->b_data, sizeof(*fs_info->super_copy));
2843	brelse(bh);
2844
2845	disk_super = fs_info->super_copy;
2846
2847	ASSERT(!memcmp(fs_info->fs_devices->fsid, fs_info->super_copy->fsid,
2848		       BTRFS_FSID_SIZE));
2849
2850	if (btrfs_fs_incompat(fs_info, METADATA_UUID)) {
2851		ASSERT(!memcmp(fs_info->fs_devices->metadata_uuid,
2852				fs_info->super_copy->metadata_uuid,
2853				BTRFS_FSID_SIZE));
2854	}
2855
2856	features = btrfs_super_flags(disk_super);
2857	if (features & BTRFS_SUPER_FLAG_CHANGING_FSID_V2) {
2858		features &= ~BTRFS_SUPER_FLAG_CHANGING_FSID_V2;
2859		btrfs_set_super_flags(disk_super, features);
2860		btrfs_info(fs_info,
2861			"found metadata UUID change in progress flag, clearing");
2862	}
2863
2864	memcpy(fs_info->super_for_commit, fs_info->super_copy,
2865	       sizeof(*fs_info->super_for_commit));
 
2866
2867	ret = btrfs_validate_mount_super(fs_info);
 
 
2868	if (ret) {
2869		btrfs_err(fs_info, "superblock contains fatal errors");
2870		err = -EINVAL;
2871		goto fail_csum;
2872	}
2873
 
2874	if (!btrfs_super_root(disk_super))
2875		goto fail_csum;
2876
2877	/* check FS state, whether FS is broken. */
2878	if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
2879		set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state);
2880
2881	/*
2882	 * run through our array of backup supers and setup
2883	 * our ring pointer to the oldest one
2884	 */
2885	generation = btrfs_super_generation(disk_super);
2886	find_oldest_super_backup(fs_info, generation);
2887
2888	/*
2889	 * In the long term, we'll store the compression type in the super
2890	 * block, and it'll be used for per file compression control.
2891	 */
2892	fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
2893
2894	ret = btrfs_parse_options(fs_info, options, sb->s_flags);
2895	if (ret) {
2896		err = ret;
2897		goto fail_csum;
2898	}
2899
2900	features = btrfs_super_incompat_flags(disk_super) &
2901		~BTRFS_FEATURE_INCOMPAT_SUPP;
2902	if (features) {
2903		btrfs_err(fs_info,
2904		    "cannot mount because of unsupported optional features (%llx)",
2905		    features);
2906		err = -EINVAL;
2907		goto fail_csum;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2908	}
2909
2910	features = btrfs_super_incompat_flags(disk_super);
2911	features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
2912	if (fs_info->compress_type == BTRFS_COMPRESS_LZO)
2913		features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
2914	else if (fs_info->compress_type == BTRFS_COMPRESS_ZSTD)
2915		features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD;
2916
2917	if (features & BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA)
2918		btrfs_info(fs_info, "has skinny extents");
2919
2920	/*
2921	 * flag our filesystem as having big metadata blocks if
2922	 * they are bigger than the page size
2923	 */
2924	if (btrfs_super_nodesize(disk_super) > PAGE_SIZE) {
2925		if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA))
2926			btrfs_info(fs_info,
2927				"flagging fs with big metadata feature");
2928		features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
2929	}
2930
2931	nodesize = btrfs_super_nodesize(disk_super);
 
2932	sectorsize = btrfs_super_sectorsize(disk_super);
2933	stripesize = sectorsize;
2934	fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids));
2935	fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
2936
2937	/* Cache block sizes */
2938	fs_info->nodesize = nodesize;
2939	fs_info->sectorsize = sectorsize;
2940	fs_info->stripesize = stripesize;
2941
2942	/*
2943	 * mixed block groups end up with duplicate but slightly offset
2944	 * extent buffers for the same range.  It leads to corruptions
2945	 */
2946	if ((features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
2947	    (sectorsize != nodesize)) {
2948		btrfs_err(fs_info,
2949"unequal nodesize/sectorsize (%u != %u) are not allowed for mixed block groups",
2950			nodesize, sectorsize);
2951		goto fail_csum;
2952	}
2953
2954	/*
2955	 * Needn't use the lock because there is no other task which will
2956	 * update the flag.
2957	 */
2958	btrfs_set_super_incompat_flags(disk_super, features);
2959
2960	features = btrfs_super_compat_ro_flags(disk_super) &
2961		~BTRFS_FEATURE_COMPAT_RO_SUPP;
2962	if (!sb_rdonly(sb) && features) {
2963		btrfs_err(fs_info,
2964	"cannot mount read-write because of unsupported optional features (%llx)",
2965		       features);
2966		err = -EINVAL;
2967		goto fail_csum;
2968	}
2969
2970	ret = btrfs_init_workqueues(fs_info, fs_devices);
2971	if (ret) {
2972		err = ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2973		goto fail_sb_buffer;
2974	}
2975
2976	sb->s_bdi->congested_fn = btrfs_congested_fn;
2977	sb->s_bdi->congested_data = fs_info;
2978	sb->s_bdi->capabilities |= BDI_CAP_CGROUP_WRITEBACK;
2979	sb->s_bdi->ra_pages = VM_READAHEAD_PAGES;
2980	sb->s_bdi->ra_pages *= btrfs_super_num_devices(disk_super);
2981	sb->s_bdi->ra_pages = max(sb->s_bdi->ra_pages, SZ_4M / PAGE_SIZE);
 
 
2982
2983	sb->s_blocksize = sectorsize;
2984	sb->s_blocksize_bits = blksize_bits(sectorsize);
2985	memcpy(&sb->s_uuid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE);
 
 
 
 
 
 
 
 
 
 
2986
2987	mutex_lock(&fs_info->chunk_mutex);
2988	ret = btrfs_read_sys_array(fs_info);
2989	mutex_unlock(&fs_info->chunk_mutex);
2990	if (ret) {
2991		btrfs_err(fs_info, "failed to read the system array: %d", ret);
 
2992		goto fail_sb_buffer;
2993	}
2994
 
 
2995	generation = btrfs_super_chunk_root_generation(disk_super);
2996	level = btrfs_super_chunk_root_level(disk_super);
2997
2998	__setup_root(chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
 
2999
3000	chunk_root->node = read_tree_block(fs_info,
3001					   btrfs_super_chunk_root(disk_super),
3002					   generation, level, NULL);
3003	if (IS_ERR(chunk_root->node) ||
3004	    !extent_buffer_uptodate(chunk_root->node)) {
3005		btrfs_err(fs_info, "failed to read chunk root");
3006		if (!IS_ERR(chunk_root->node))
3007			free_extent_buffer(chunk_root->node);
3008		chunk_root->node = NULL;
3009		goto fail_tree_roots;
3010	}
3011	btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
3012	chunk_root->commit_root = btrfs_root_node(chunk_root);
3013
3014	read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
3015	   btrfs_header_chunk_tree_uuid(chunk_root->node), BTRFS_UUID_SIZE);
3016
3017	ret = btrfs_read_chunk_tree(fs_info);
3018	if (ret) {
3019		btrfs_err(fs_info, "failed to read chunk tree: %d", ret);
 
3020		goto fail_tree_roots;
3021	}
3022
3023	/*
3024	 * Keep the devid that is marked to be the target device for the
3025	 * device replace procedure
3026	 */
3027	btrfs_free_extra_devids(fs_devices, 0);
3028
3029	if (!fs_devices->latest_bdev) {
3030		btrfs_err(fs_info, "failed to read devices");
 
3031		goto fail_tree_roots;
3032	}
3033
3034retry_root_backup:
 
 
3035	generation = btrfs_super_generation(disk_super);
3036	level = btrfs_super_root_level(disk_super);
3037
3038	tree_root->node = read_tree_block(fs_info,
3039					  btrfs_super_root(disk_super),
3040					  generation, level, NULL);
3041	if (IS_ERR(tree_root->node) ||
3042	    !extent_buffer_uptodate(tree_root->node)) {
3043		btrfs_warn(fs_info, "failed to read tree root");
3044		if (!IS_ERR(tree_root->node))
3045			free_extent_buffer(tree_root->node);
3046		tree_root->node = NULL;
3047		goto recovery_tree_root;
3048	}
3049
3050	btrfs_set_root_node(&tree_root->root_item, tree_root->node);
3051	tree_root->commit_root = btrfs_root_node(tree_root);
3052	btrfs_set_root_refs(&tree_root->root_item, 1);
3053
3054	mutex_lock(&tree_root->objectid_mutex);
3055	ret = btrfs_find_highest_objectid(tree_root,
3056					&tree_root->highest_objectid);
3057	if (ret) {
3058		mutex_unlock(&tree_root->objectid_mutex);
 
 
3059		goto recovery_tree_root;
3060	}
 
 
3061
3062	ASSERT(tree_root->highest_objectid <= BTRFS_LAST_FREE_OBJECTID);
3063
3064	mutex_unlock(&tree_root->objectid_mutex);
 
 
 
 
 
 
3065
3066	ret = btrfs_read_roots(fs_info);
3067	if (ret)
 
 
3068		goto recovery_tree_root;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3069
3070	fs_info->generation = generation;
3071	fs_info->last_trans_committed = generation;
3072
3073	ret = btrfs_verify_dev_extents(fs_info);
3074	if (ret) {
3075		btrfs_err(fs_info,
3076			  "failed to verify dev extents against chunks: %d",
3077			  ret);
3078		goto fail_block_groups;
3079	}
3080	ret = btrfs_recover_balance(fs_info);
3081	if (ret) {
3082		btrfs_err(fs_info, "failed to recover balance: %d", ret);
3083		goto fail_block_groups;
3084	}
3085
3086	ret = btrfs_init_dev_stats(fs_info);
3087	if (ret) {
3088		btrfs_err(fs_info, "failed to init dev_stats: %d", ret);
 
3089		goto fail_block_groups;
3090	}
3091
3092	ret = btrfs_init_dev_replace(fs_info);
3093	if (ret) {
3094		btrfs_err(fs_info, "failed to init dev_replace: %d", ret);
3095		goto fail_block_groups;
3096	}
3097
3098	btrfs_free_extra_devids(fs_devices, 1);
3099
3100	ret = btrfs_sysfs_add_fsid(fs_devices, NULL);
3101	if (ret) {
3102		btrfs_err(fs_info, "failed to init sysfs fsid interface: %d",
3103				ret);
3104		goto fail_block_groups;
3105	}
3106
3107	ret = btrfs_sysfs_add_device(fs_devices);
3108	if (ret) {
3109		btrfs_err(fs_info, "failed to init sysfs device interface: %d",
3110				ret);
3111		goto fail_fsdev_sysfs;
3112	}
3113
3114	ret = btrfs_sysfs_add_mounted(fs_info);
3115	if (ret) {
3116		btrfs_err(fs_info, "failed to init sysfs interface: %d", ret);
3117		goto fail_fsdev_sysfs;
3118	}
3119
3120	ret = btrfs_init_space_info(fs_info);
3121	if (ret) {
3122		btrfs_err(fs_info, "failed to initialize space info: %d", ret);
3123		goto fail_sysfs;
3124	}
3125
3126	ret = btrfs_read_block_groups(fs_info);
3127	if (ret) {
3128		btrfs_err(fs_info, "failed to read block groups: %d", ret);
3129		goto fail_sysfs;
3130	}
3131
3132	if (!sb_rdonly(sb) && !btrfs_check_rw_degradable(fs_info, NULL)) {
3133		btrfs_warn(fs_info,
3134		"writable mount is not allowed due to too many missing devices");
 
 
 
3135		goto fail_sysfs;
3136	}
3137
3138	fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
3139					       "btrfs-cleaner");
3140	if (IS_ERR(fs_info->cleaner_kthread))
3141		goto fail_sysfs;
3142
3143	fs_info->transaction_kthread = kthread_run(transaction_kthread,
3144						   tree_root,
3145						   "btrfs-transaction");
3146	if (IS_ERR(fs_info->transaction_kthread))
3147		goto fail_cleaner;
3148
3149	if (!btrfs_test_opt(fs_info, NOSSD) &&
 
3150	    !fs_info->fs_devices->rotating) {
3151		btrfs_set_and_info(fs_info, SSD, "enabling ssd optimizations");
 
 
3152	}
3153
3154	/*
3155	 * Mount does not set all options immediately, we can do it now and do
3156	 * not have to wait for transaction commit
3157	 */
3158	btrfs_apply_pending_changes(fs_info);
3159
3160#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3161	if (btrfs_test_opt(fs_info, CHECK_INTEGRITY)) {
3162		ret = btrfsic_mount(fs_info, fs_devices,
3163				    btrfs_test_opt(fs_info,
3164					CHECK_INTEGRITY_INCLUDING_EXTENT_DATA) ?
3165				    1 : 0,
3166				    fs_info->check_integrity_print_mask);
3167		if (ret)
3168			btrfs_warn(fs_info,
3169				"failed to initialize integrity check module: %d",
3170				ret);
3171	}
3172#endif
3173	ret = btrfs_read_qgroup_config(fs_info);
3174	if (ret)
3175		goto fail_trans_kthread;
3176
3177	if (btrfs_build_ref_tree(fs_info))
3178		btrfs_err(fs_info, "couldn't build ref tree");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3179
3180	/* do not make disk changes in broken FS or nologreplay is given */
3181	if (btrfs_super_log_root(disk_super) != 0 &&
3182	    !btrfs_test_opt(fs_info, NOLOGREPLAY)) {
3183		ret = btrfs_replay_log(fs_info, fs_devices);
 
 
 
 
 
 
 
 
3184		if (ret) {
3185			err = ret;
 
 
 
3186			goto fail_qgroup;
3187		}
 
 
 
 
 
 
3188	}
3189
3190	ret = btrfs_find_orphan_roots(fs_info);
3191	if (ret)
3192		goto fail_qgroup;
3193
3194	if (!sb_rdonly(sb)) {
3195		ret = btrfs_cleanup_fs_roots(fs_info);
3196		if (ret)
3197			goto fail_qgroup;
3198
3199		mutex_lock(&fs_info->cleaner_mutex);
3200		ret = btrfs_recover_relocation(tree_root);
3201		mutex_unlock(&fs_info->cleaner_mutex);
3202		if (ret < 0) {
3203			btrfs_warn(fs_info, "failed to recover relocation: %d",
3204					ret);
3205			err = -EINVAL;
3206			goto fail_qgroup;
3207		}
3208	}
3209
3210	location.objectid = BTRFS_FS_TREE_OBJECTID;
3211	location.type = BTRFS_ROOT_ITEM_KEY;
3212	location.offset = 0;
3213
3214	fs_info->fs_root = btrfs_read_fs_root_no_name(fs_info, &location);
3215	if (IS_ERR(fs_info->fs_root)) {
3216		err = PTR_ERR(fs_info->fs_root);
3217		btrfs_warn(fs_info, "failed to read fs tree: %d", err);
3218		goto fail_qgroup;
3219	}
3220
3221	if (sb_rdonly(sb))
3222		return 0;
3223
3224	if (btrfs_test_opt(fs_info, CLEAR_CACHE) &&
3225	    btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3226		clear_free_space_tree = 1;
3227	} else if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
3228		   !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID)) {
3229		btrfs_warn(fs_info, "free space tree is invalid");
3230		clear_free_space_tree = 1;
3231	}
3232
3233	if (clear_free_space_tree) {
3234		btrfs_info(fs_info, "clearing free space tree");
3235		ret = btrfs_clear_free_space_tree(fs_info);
3236		if (ret) {
3237			btrfs_warn(fs_info,
3238				   "failed to clear free space tree: %d", ret);
3239			close_ctree(fs_info);
3240			return ret;
3241		}
3242	}
3243
3244	if (btrfs_test_opt(fs_info, FREE_SPACE_TREE) &&
3245	    !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
3246		btrfs_info(fs_info, "creating free space tree");
3247		ret = btrfs_create_free_space_tree(fs_info);
3248		if (ret) {
3249			btrfs_warn(fs_info,
3250				"failed to create free space tree: %d", ret);
3251			close_ctree(fs_info);
3252			return ret;
3253		}
3254	}
3255
3256	down_read(&fs_info->cleanup_work_sem);
3257	if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) ||
3258	    (ret = btrfs_orphan_cleanup(fs_info->tree_root))) {
3259		up_read(&fs_info->cleanup_work_sem);
3260		close_ctree(fs_info);
3261		return ret;
3262	}
3263	up_read(&fs_info->cleanup_work_sem);
3264
3265	ret = btrfs_resume_balance_async(fs_info);
3266	if (ret) {
3267		btrfs_warn(fs_info, "failed to resume balance: %d", ret);
3268		close_ctree(fs_info);
3269		return ret;
3270	}
3271
3272	ret = btrfs_resume_dev_replace_async(fs_info);
3273	if (ret) {
3274		btrfs_warn(fs_info, "failed to resume device replace: %d", ret);
3275		close_ctree(fs_info);
3276		return ret;
3277	}
3278
3279	btrfs_qgroup_rescan_resume(fs_info);
3280
3281	if (!fs_info->uuid_root) {
3282		btrfs_info(fs_info, "creating UUID tree");
3283		ret = btrfs_create_uuid_tree(fs_info);
3284		if (ret) {
3285			btrfs_warn(fs_info,
3286				"failed to create the UUID tree: %d", ret);
3287			close_ctree(fs_info);
3288			return ret;
3289		}
3290	} else if (btrfs_test_opt(fs_info, RESCAN_UUID_TREE) ||
3291		   fs_info->generation !=
3292				btrfs_super_uuid_tree_generation(disk_super)) {
3293		btrfs_info(fs_info, "checking UUID tree");
3294		ret = btrfs_check_uuid_tree(fs_info);
3295		if (ret) {
3296			btrfs_warn(fs_info,
3297				"failed to check the UUID tree: %d", ret);
3298			close_ctree(fs_info);
3299			return ret;
3300		}
3301	} else {
3302		set_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags);
3303	}
3304	set_bit(BTRFS_FS_OPEN, &fs_info->flags);
3305
3306	/*
3307	 * backuproot only affect mount behavior, and if open_ctree succeeded,
3308	 * no need to keep the flag
3309	 */
3310	btrfs_clear_opt(fs_info->mount_opt, USEBACKUPROOT);
3311
3312	return 0;
3313
3314fail_qgroup:
3315	btrfs_free_qgroup_config(fs_info);
3316fail_trans_kthread:
3317	kthread_stop(fs_info->transaction_kthread);
3318	btrfs_cleanup_transaction(fs_info);
3319	btrfs_free_fs_roots(fs_info);
3320fail_cleaner:
3321	kthread_stop(fs_info->cleaner_kthread);
3322
3323	/*
3324	 * make sure we're done with the btree inode before we stop our
3325	 * kthreads
3326	 */
3327	filemap_write_and_wait(fs_info->btree_inode->i_mapping);
3328
3329fail_sysfs:
3330	btrfs_sysfs_remove_mounted(fs_info);
3331
3332fail_fsdev_sysfs:
3333	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
3334
3335fail_block_groups:
3336	btrfs_put_block_group_cache(fs_info);
 
3337
3338fail_tree_roots:
3339	free_root_pointers(fs_info, 1);
3340	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
3341
3342fail_sb_buffer:
3343	btrfs_stop_all_workers(fs_info);
3344	btrfs_free_block_groups(fs_info);
3345fail_csum:
3346	btrfs_free_csum_hash(fs_info);
3347fail_alloc:
3348fail_iput:
3349	btrfs_mapping_tree_free(&fs_info->mapping_tree);
3350
3351	iput(fs_info->btree_inode);
3352fail_bio_counter:
3353	percpu_counter_destroy(&fs_info->dev_replace.bio_counter);
3354fail_delalloc_bytes:
3355	percpu_counter_destroy(&fs_info->delalloc_bytes);
3356fail_dirty_metadata_bytes:
3357	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
3358fail_dio_bytes:
3359	percpu_counter_destroy(&fs_info->dio_bytes);
3360fail_srcu:
3361	cleanup_srcu_struct(&fs_info->subvol_srcu);
3362fail:
3363	btrfs_free_stripe_hash_table(fs_info);
3364	btrfs_close_devices(fs_info->fs_devices);
3365	return err;
3366
3367recovery_tree_root:
3368	if (!btrfs_test_opt(fs_info, USEBACKUPROOT))
3369		goto fail_tree_roots;
3370
3371	free_root_pointers(fs_info, 0);
3372
3373	/* don't use the log in recovery mode, it won't be valid */
3374	btrfs_set_super_log_root(disk_super, 0);
3375
3376	/* we can't trust the free space cache either */
3377	btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
3378
3379	ret = next_root_backup(fs_info, fs_info->super_copy,
3380			       &num_backups_tried, &backup_index);
3381	if (ret == -1)
3382		goto fail_block_groups;
3383	goto retry_root_backup;
3384}
3385ALLOW_ERROR_INJECTION(open_ctree, ERRNO);
3386
3387static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
3388{
3389	if (uptodate) {
3390		set_buffer_uptodate(bh);
3391	} else {
3392		struct btrfs_device *device = (struct btrfs_device *)
3393			bh->b_private;
3394
3395		btrfs_warn_rl_in_rcu(device->fs_info,
3396				"lost page write due to IO error on %s",
3397					  rcu_str_deref(device->name));
3398		/* note, we don't set_buffer_write_io_error because we have
3399		 * our own ways of dealing with the IO errors
3400		 */
3401		clear_buffer_uptodate(bh);
3402		btrfs_dev_stat_inc_and_print(device, BTRFS_DEV_STAT_WRITE_ERRS);
3403	}
3404	unlock_buffer(bh);
3405	put_bh(bh);
3406}
3407
3408int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num,
3409			struct buffer_head **bh_ret)
3410{
3411	struct buffer_head *bh;
3412	struct btrfs_super_block *super;
3413	u64 bytenr;
3414
3415	bytenr = btrfs_sb_offset(copy_num);
3416	if (bytenr + BTRFS_SUPER_INFO_SIZE >= i_size_read(bdev->bd_inode))
3417		return -EINVAL;
3418
3419	bh = __bread(bdev, bytenr / BTRFS_BDEV_BLOCKSIZE, BTRFS_SUPER_INFO_SIZE);
3420	/*
3421	 * If we fail to read from the underlying devices, as of now
3422	 * the best option we have is to mark it EIO.
3423	 */
3424	if (!bh)
3425		return -EIO;
3426
3427	super = (struct btrfs_super_block *)bh->b_data;
3428	if (btrfs_super_bytenr(super) != bytenr ||
3429		    btrfs_super_magic(super) != BTRFS_MAGIC) {
3430		brelse(bh);
3431		return -EINVAL;
3432	}
3433
3434	*bh_ret = bh;
3435	return 0;
3436}
3437
3438
3439struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
3440{
3441	struct buffer_head *bh;
3442	struct buffer_head *latest = NULL;
3443	struct btrfs_super_block *super;
3444	int i;
3445	u64 transid = 0;
3446	int ret = -EINVAL;
3447
3448	/* we would like to check all the supers, but that would make
3449	 * a btrfs mount succeed after a mkfs from a different FS.
3450	 * So, we need to add a special mount option to scan for
3451	 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
3452	 */
3453	for (i = 0; i < 1; i++) {
3454		ret = btrfs_read_dev_one_super(bdev, i, &bh);
3455		if (ret)
 
 
 
 
 
3456			continue;
3457
3458		super = (struct btrfs_super_block *)bh->b_data;
 
 
 
 
 
3459
3460		if (!latest || btrfs_super_generation(super) > transid) {
3461			brelse(latest);
3462			latest = bh;
3463			transid = btrfs_super_generation(super);
3464		} else {
3465			brelse(bh);
3466		}
3467	}
3468
3469	if (!latest)
3470		return ERR_PTR(ret);
3471
3472	return latest;
3473}
3474
3475/*
3476 * Write superblock @sb to the @device. Do not wait for completion, all the
3477 * buffer heads we write are pinned.
 
3478 *
3479 * Write @max_mirrors copies of the superblock, where 0 means default that fit
3480 * the expected device size at commit time. Note that max_mirrors must be
3481 * same for write and wait phases.
3482 *
3483 * Return number of errors when buffer head is not found or submission fails.
3484 */
3485static int write_dev_supers(struct btrfs_device *device,
3486			    struct btrfs_super_block *sb, int max_mirrors)
 
3487{
3488	struct btrfs_fs_info *fs_info = device->fs_info;
3489	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
3490	struct buffer_head *bh;
3491	int i;
3492	int ret;
3493	int errors = 0;
 
3494	u64 bytenr;
3495	int op_flags;
3496
3497	if (max_mirrors == 0)
3498		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
3499
3500	shash->tfm = fs_info->csum_shash;
3501
3502	for (i = 0; i < max_mirrors; i++) {
3503		bytenr = btrfs_sb_offset(i);
3504		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
3505		    device->commit_total_bytes)
3506			break;
3507
3508		btrfs_set_super_bytenr(sb, bytenr);
 
 
 
 
 
 
 
 
 
3509
3510		crypto_shash_init(shash);
3511		crypto_shash_update(shash, (const char *)sb + BTRFS_CSUM_SIZE,
3512				    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
3513		crypto_shash_final(shash, sb->csum);
3514
3515		/* One reference for us, and we leave it for the caller */
3516		bh = __getblk(device->bdev, bytenr / BTRFS_BDEV_BLOCKSIZE,
3517			      BTRFS_SUPER_INFO_SIZE);
3518		if (!bh) {
3519			btrfs_err(device->fs_info,
3520			    "couldn't get super buffer head for bytenr %llu",
3521			    bytenr);
3522			errors++;
3523			continue;
3524		}
 
3525
3526		memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
 
 
 
 
 
3527
3528		/* one reference for submit_bh */
3529		get_bh(bh);
 
 
 
 
 
 
 
 
 
 
3530
3531		set_buffer_uptodate(bh);
3532		lock_buffer(bh);
3533		bh->b_end_io = btrfs_end_buffer_write_sync;
3534		bh->b_private = device;
 
 
 
 
 
 
3535
3536		/*
3537		 * we fua the first super.  The others we allow
3538		 * to go down lazy.
3539		 */
3540		op_flags = REQ_SYNC | REQ_META | REQ_PRIO;
3541		if (i == 0 && !btrfs_test_opt(device->fs_info, NOBARRIER))
3542			op_flags |= REQ_FUA;
3543		ret = btrfsic_submit_bh(REQ_OP_WRITE, op_flags, bh);
3544		if (ret)
3545			errors++;
3546	}
3547	return errors < i ? 0 : -1;
3548}
3549
3550/*
3551 * Wait for write completion of superblocks done by write_dev_supers,
3552 * @max_mirrors same for write and wait phases.
3553 *
3554 * Return number of errors when buffer head is not found or not marked up to
3555 * date.
3556 */
3557static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
3558{
3559	struct buffer_head *bh;
3560	int i;
3561	int errors = 0;
3562	bool primary_failed = false;
3563	u64 bytenr;
3564
3565	if (max_mirrors == 0)
3566		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
3567
3568	for (i = 0; i < max_mirrors; i++) {
3569		bytenr = btrfs_sb_offset(i);
3570		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
3571		    device->commit_total_bytes)
3572			break;
3573
3574		bh = __find_get_block(device->bdev,
3575				      bytenr / BTRFS_BDEV_BLOCKSIZE,
3576				      BTRFS_SUPER_INFO_SIZE);
3577		if (!bh) {
3578			errors++;
3579			if (i == 0)
3580				primary_failed = true;
3581			continue;
3582		}
3583		wait_on_buffer(bh);
3584		if (!buffer_uptodate(bh)) {
3585			errors++;
3586			if (i == 0)
3587				primary_failed = true;
3588		}
3589
3590		/* drop our reference */
3591		brelse(bh);
3592
3593		/* drop the reference from the writing run */
3594		brelse(bh);
3595	}
3596
3597	/* log error, force error return */
3598	if (primary_failed) {
3599		btrfs_err(device->fs_info, "error writing primary super block to device %llu",
3600			  device->devid);
3601		return -1;
3602	}
3603
3604	return errors < i ? 0 : -1;
3605}
3606
3607/*
3608 * endio for the write_dev_flush, this will wake anyone waiting
3609 * for the barrier when it is done
3610 */
3611static void btrfs_end_empty_barrier(struct bio *bio)
3612{
3613	complete(bio->bi_private);
 
 
 
 
 
 
 
3614}
3615
3616/*
3617 * Submit a flush request to the device if it supports it. Error handling is
3618 * done in the waiting counterpart.
 
 
 
3619 */
3620static void write_dev_flush(struct btrfs_device *device)
3621{
3622	struct request_queue *q = bdev_get_queue(device->bdev);
3623	struct bio *bio = device->flush_bio;
3624
3625	if (!test_bit(QUEUE_FLAG_WC, &q->queue_flags))
3626		return;
3627
3628	bio_reset(bio);
3629	bio->bi_end_io = btrfs_end_empty_barrier;
3630	bio_set_dev(bio, device->bdev);
3631	bio->bi_opf = REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH;
3632	init_completion(&device->flush_wait);
3633	bio->bi_private = &device->flush_wait;
3634
3635	btrfsic_submit_bio(bio);
3636	set_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
3637}
3638
3639/*
3640 * If the flush bio has been submitted by write_dev_flush, wait for it.
3641 */
3642static blk_status_t wait_dev_flush(struct btrfs_device *device)
3643{
3644	struct bio *bio = device->flush_bio;
 
 
 
3645
3646	if (!test_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state))
3647		return BLK_STS_OK;
 
3648
3649	clear_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state);
3650	wait_for_completion_io(&device->flush_wait);
3651
3652	return bio->bi_status;
3653}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3654
3655static int check_barrier_error(struct btrfs_fs_info *fs_info)
3656{
3657	if (!btrfs_check_rw_degradable(fs_info, NULL))
3658		return -EIO;
3659	return 0;
3660}
3661
3662/*
3663 * send an empty flush down to each device in parallel,
3664 * then wait for them
3665 */
3666static int barrier_all_devices(struct btrfs_fs_info *info)
3667{
3668	struct list_head *head;
3669	struct btrfs_device *dev;
 
3670	int errors_wait = 0;
3671	blk_status_t ret;
3672
3673	lockdep_assert_held(&info->fs_devices->device_list_mutex);
3674	/* send down all the barriers */
3675	head = &info->fs_devices->devices;
3676	list_for_each_entry(dev, head, dev_list) {
3677		if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
3678			continue;
3679		if (!dev->bdev)
 
3680			continue;
3681		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3682		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
3683			continue;
3684
3685		write_dev_flush(dev);
3686		dev->last_flush_error = BLK_STS_OK;
 
3687	}
3688
3689	/* wait for all the barriers */
3690	list_for_each_entry(dev, head, dev_list) {
3691		if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
3692			continue;
3693		if (!dev->bdev) {
3694			errors_wait++;
3695			continue;
3696		}
3697		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3698		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
3699			continue;
3700
3701		ret = wait_dev_flush(dev);
3702		if (ret) {
3703			dev->last_flush_error = ret;
3704			btrfs_dev_stat_inc_and_print(dev,
3705					BTRFS_DEV_STAT_FLUSH_ERRS);
3706			errors_wait++;
3707		}
3708	}
3709
3710	if (errors_wait) {
3711		/*
3712		 * At some point we need the status of all disks
3713		 * to arrive at the volume status. So error checking
3714		 * is being pushed to a separate loop.
3715		 */
3716		return check_barrier_error(info);
3717	}
 
 
 
3718	return 0;
3719}
3720
3721int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags)
 
3722{
3723	int raid_type;
3724	int min_tolerated = INT_MAX;
3725
3726	if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 ||
3727	    (flags & BTRFS_AVAIL_ALLOC_BIT_SINGLE))
3728		min_tolerated = min_t(int, min_tolerated,
3729				    btrfs_raid_array[BTRFS_RAID_SINGLE].
3730				    tolerated_failures);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3731
3732	for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
3733		if (raid_type == BTRFS_RAID_SINGLE)
3734			continue;
3735		if (!(flags & btrfs_raid_array[raid_type].bg_flag))
3736			continue;
3737		min_tolerated = min_t(int, min_tolerated,
3738				    btrfs_raid_array[raid_type].
3739				    tolerated_failures);
3740	}
3741
3742	if (min_tolerated == INT_MAX) {
3743		pr_warn("BTRFS: unknown raid flag: %llu", flags);
3744		min_tolerated = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3745	}
3746
3747	return min_tolerated;
3748}
3749
3750int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors)
3751{
3752	struct list_head *head;
3753	struct btrfs_device *dev;
3754	struct btrfs_super_block *sb;
3755	struct btrfs_dev_item *dev_item;
3756	int ret;
3757	int do_barriers;
3758	int max_errors;
3759	int total_errors = 0;
3760	u64 flags;
3761
3762	do_barriers = !btrfs_test_opt(fs_info, NOBARRIER);
 
3763
3764	/*
3765	 * max_mirrors == 0 indicates we're from commit_transaction,
3766	 * not from fsync where the tree roots in fs_info have not
3767	 * been consistent on disk.
3768	 */
3769	if (max_mirrors == 0)
3770		backup_super_roots(fs_info);
3771
3772	sb = fs_info->super_for_commit;
3773	dev_item = &sb->dev_item;
3774
3775	mutex_lock(&fs_info->fs_devices->device_list_mutex);
3776	head = &fs_info->fs_devices->devices;
3777	max_errors = btrfs_super_num_devices(fs_info->super_copy) - 1;
3778
3779	if (do_barriers) {
3780		ret = barrier_all_devices(fs_info);
3781		if (ret) {
3782			mutex_unlock(
3783				&fs_info->fs_devices->device_list_mutex);
3784			btrfs_handle_fs_error(fs_info, ret,
3785					      "errors while submitting device barriers.");
3786			return ret;
3787		}
3788	}
3789
3790	list_for_each_entry(dev, head, dev_list) {
3791		if (!dev->bdev) {
3792			total_errors++;
3793			continue;
3794		}
3795		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3796		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
3797			continue;
3798
3799		btrfs_set_stack_device_generation(dev_item, 0);
3800		btrfs_set_stack_device_type(dev_item, dev->type);
3801		btrfs_set_stack_device_id(dev_item, dev->devid);
3802		btrfs_set_stack_device_total_bytes(dev_item,
3803						   dev->commit_total_bytes);
3804		btrfs_set_stack_device_bytes_used(dev_item,
3805						  dev->commit_bytes_used);
3806		btrfs_set_stack_device_io_align(dev_item, dev->io_align);
3807		btrfs_set_stack_device_io_width(dev_item, dev->io_width);
3808		btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
3809		memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
3810		memcpy(dev_item->fsid, dev->fs_devices->metadata_uuid,
3811		       BTRFS_FSID_SIZE);
3812
3813		flags = btrfs_super_flags(sb);
3814		btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
3815
3816		ret = btrfs_validate_write_super(fs_info, sb);
3817		if (ret < 0) {
3818			mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3819			btrfs_handle_fs_error(fs_info, -EUCLEAN,
3820				"unexpected superblock corruption detected");
3821			return -EUCLEAN;
3822		}
3823
3824		ret = write_dev_supers(dev, sb, max_mirrors);
3825		if (ret)
3826			total_errors++;
3827	}
3828	if (total_errors > max_errors) {
3829		btrfs_err(fs_info, "%d errors while writing supers",
3830			  total_errors);
3831		mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3832
3833		/* FUA is masked off if unsupported and can't be the reason */
3834		btrfs_handle_fs_error(fs_info, -EIO,
3835				      "%d errors while writing supers",
3836				      total_errors);
3837		return -EIO;
3838	}
3839
3840	total_errors = 0;
3841	list_for_each_entry(dev, head, dev_list) {
3842		if (!dev->bdev)
3843			continue;
3844		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3845		    !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))
3846			continue;
3847
3848		ret = wait_dev_supers(dev, max_mirrors);
3849		if (ret)
3850			total_errors++;
3851	}
3852	mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3853	if (total_errors > max_errors) {
3854		btrfs_handle_fs_error(fs_info, -EIO,
3855				      "%d errors while writing supers",
3856				      total_errors);
3857		return -EIO;
3858	}
3859	return 0;
3860}
3861
 
 
 
 
 
 
3862/* Drop a fs root from the radix tree and free it. */
3863void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
3864				  struct btrfs_root *root)
3865{
3866	spin_lock(&fs_info->fs_roots_radix_lock);
3867	radix_tree_delete(&fs_info->fs_roots_radix,
3868			  (unsigned long)root->root_key.objectid);
3869	spin_unlock(&fs_info->fs_roots_radix_lock);
3870
3871	if (btrfs_root_refs(&root->root_item) == 0)
3872		synchronize_srcu(&fs_info->subvol_srcu);
3873
3874	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
3875		btrfs_free_log(NULL, root);
3876		if (root->reloc_root) {
3877			free_extent_buffer(root->reloc_root->node);
3878			free_extent_buffer(root->reloc_root->commit_root);
3879			btrfs_put_fs_root(root->reloc_root);
3880			root->reloc_root = NULL;
3881		}
3882	}
3883
3884	if (root->free_ino_pinned)
3885		__btrfs_remove_free_space_cache(root->free_ino_pinned);
3886	if (root->free_ino_ctl)
3887		__btrfs_remove_free_space_cache(root->free_ino_ctl);
3888	btrfs_free_fs_root(root);
3889}
3890
3891void btrfs_free_fs_root(struct btrfs_root *root)
3892{
3893	iput(root->ino_cache_inode);
3894	WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
 
 
3895	if (root->anon_dev)
3896		free_anon_bdev(root->anon_dev);
3897	if (root->subv_writers)
3898		btrfs_free_subvolume_writers(root->subv_writers);
3899	free_extent_buffer(root->node);
3900	free_extent_buffer(root->commit_root);
3901	kfree(root->free_ino_ctl);
3902	kfree(root->free_ino_pinned);
 
3903	btrfs_put_fs_root(root);
3904}
3905
 
 
 
 
 
3906int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
3907{
3908	u64 root_objectid = 0;
3909	struct btrfs_root *gang[8];
3910	int i = 0;
3911	int err = 0;
3912	unsigned int ret = 0;
3913	int index;
3914
3915	while (1) {
3916		index = srcu_read_lock(&fs_info->subvol_srcu);
3917		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
3918					     (void **)gang, root_objectid,
3919					     ARRAY_SIZE(gang));
3920		if (!ret) {
3921			srcu_read_unlock(&fs_info->subvol_srcu, index);
3922			break;
3923		}
3924		root_objectid = gang[ret - 1]->root_key.objectid + 1;
3925
 
3926		for (i = 0; i < ret; i++) {
3927			/* Avoid to grab roots in dead_roots */
3928			if (btrfs_root_refs(&gang[i]->root_item) == 0) {
3929				gang[i] = NULL;
3930				continue;
3931			}
3932			/* grab all the search result for later use */
3933			gang[i] = btrfs_grab_fs_root(gang[i]);
3934		}
3935		srcu_read_unlock(&fs_info->subvol_srcu, index);
3936
3937		for (i = 0; i < ret; i++) {
3938			if (!gang[i])
3939				continue;
3940			root_objectid = gang[i]->root_key.objectid;
3941			err = btrfs_orphan_cleanup(gang[i]);
3942			if (err)
3943				break;
3944			btrfs_put_fs_root(gang[i]);
3945		}
3946		root_objectid++;
3947	}
3948
3949	/* release the uncleaned roots due to error */
3950	for (; i < ret; i++) {
3951		if (gang[i])
3952			btrfs_put_fs_root(gang[i]);
3953	}
3954	return err;
3955}
3956
3957int btrfs_commit_super(struct btrfs_fs_info *fs_info)
3958{
3959	struct btrfs_root *root = fs_info->tree_root;
3960	struct btrfs_trans_handle *trans;
3961
3962	mutex_lock(&fs_info->cleaner_mutex);
3963	btrfs_run_delayed_iputs(fs_info);
3964	mutex_unlock(&fs_info->cleaner_mutex);
3965	wake_up_process(fs_info->cleaner_kthread);
3966
3967	/* wait until ongoing cleanup work done */
3968	down_write(&fs_info->cleanup_work_sem);
3969	up_write(&fs_info->cleanup_work_sem);
3970
3971	trans = btrfs_join_transaction(root);
3972	if (IS_ERR(trans))
3973		return PTR_ERR(trans);
3974	return btrfs_commit_transaction(trans);
3975}
3976
3977void close_ctree(struct btrfs_fs_info *fs_info)
3978{
 
3979	int ret;
3980
3981	set_bit(BTRFS_FS_CLOSING_START, &fs_info->flags);
3982	/*
3983	 * We don't want the cleaner to start new transactions, add more delayed
3984	 * iputs, etc. while we're closing. We can't use kthread_stop() yet
3985	 * because that frees the task_struct, and the transaction kthread might
3986	 * still try to wake up the cleaner.
3987	 */
3988	kthread_park(fs_info->cleaner_kthread);
3989
3990	/* wait for the qgroup rescan worker to stop */
3991	btrfs_qgroup_wait_for_completion(fs_info, false);
3992
3993	/* wait for the uuid_scan task to finish */
3994	down(&fs_info->uuid_tree_rescan_sem);
3995	/* avoid complains from lockdep et al., set sem back to initial state */
3996	up(&fs_info->uuid_tree_rescan_sem);
3997
3998	/* pause restriper - we want to resume on mount */
3999	btrfs_pause_balance(fs_info);
4000
4001	btrfs_dev_replace_suspend_for_unmount(fs_info);
4002
4003	btrfs_scrub_cancel(fs_info);
4004
4005	/* wait for any defraggers to finish */
4006	wait_event(fs_info->transaction_wait,
4007		   (atomic_read(&fs_info->defrag_running) == 0));
4008
4009	/* clear out the rbtree of defraggable inodes */
4010	btrfs_cleanup_defrag_inodes(fs_info);
4011
4012	cancel_work_sync(&fs_info->async_reclaim_work);
4013
4014	if (!sb_rdonly(fs_info->sb)) {
4015		/*
4016		 * The cleaner kthread is stopped, so do one final pass over
4017		 * unused block groups.
4018		 */
4019		btrfs_delete_unused_bgs(fs_info);
4020
4021		ret = btrfs_commit_super(fs_info);
4022		if (ret)
4023			btrfs_err(fs_info, "commit super ret %d", ret);
4024	}
4025
4026	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state) ||
4027	    test_bit(BTRFS_FS_STATE_TRANS_ABORTED, &fs_info->fs_state))
4028		btrfs_error_commit_super(fs_info);
4029
4030	kthread_stop(fs_info->transaction_kthread);
4031	kthread_stop(fs_info->cleaner_kthread);
4032
4033	ASSERT(list_empty(&fs_info->delayed_iputs));
4034	set_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags);
4035
4036	btrfs_free_qgroup_config(fs_info);
4037	ASSERT(list_empty(&fs_info->delalloc_roots));
4038
4039	if (percpu_counter_sum(&fs_info->delalloc_bytes)) {
4040		btrfs_info(fs_info, "at unmount delalloc count %lld",
4041		       percpu_counter_sum(&fs_info->delalloc_bytes));
4042	}
4043
4044	if (percpu_counter_sum(&fs_info->dio_bytes))
4045		btrfs_info(fs_info, "at unmount dio bytes count %lld",
4046			   percpu_counter_sum(&fs_info->dio_bytes));
4047
4048	btrfs_sysfs_remove_mounted(fs_info);
4049	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
4050
4051	btrfs_free_fs_roots(fs_info);
4052
4053	btrfs_put_block_group_cache(fs_info);
4054
4055	/*
4056	 * we must make sure there is not any read request to
4057	 * submit after we stopping all workers.
4058	 */
4059	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
4060	btrfs_stop_all_workers(fs_info);
4061
4062	btrfs_free_block_groups(fs_info);
4063
4064	clear_bit(BTRFS_FS_OPEN, &fs_info->flags);
 
4065	free_root_pointers(fs_info, 1);
4066
4067	iput(fs_info->btree_inode);
4068
4069#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4070	if (btrfs_test_opt(fs_info, CHECK_INTEGRITY))
4071		btrfsic_unmount(fs_info->fs_devices);
4072#endif
4073
4074	btrfs_mapping_tree_free(&fs_info->mapping_tree);
4075	btrfs_close_devices(fs_info->fs_devices);
 
4076
4077	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
4078	percpu_counter_destroy(&fs_info->delalloc_bytes);
4079	percpu_counter_destroy(&fs_info->dio_bytes);
4080	percpu_counter_destroy(&fs_info->dev_replace.bio_counter);
4081	cleanup_srcu_struct(&fs_info->subvol_srcu);
4082
4083	btrfs_free_csum_hash(fs_info);
4084	btrfs_free_stripe_hash_table(fs_info);
4085	btrfs_free_ref_cache(fs_info);
 
 
 
 
4086}
4087
4088int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
4089			  int atomic)
4090{
4091	int ret;
4092	struct inode *btree_inode = buf->pages[0]->mapping->host;
4093
4094	ret = extent_buffer_uptodate(buf);
4095	if (!ret)
4096		return ret;
4097
4098	ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
4099				    parent_transid, atomic);
4100	if (ret == -EAGAIN)
4101		return ret;
4102	return !ret;
4103}
4104
 
 
 
 
 
4105void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
4106{
4107	struct btrfs_fs_info *fs_info;
4108	struct btrfs_root *root;
4109	u64 transid = btrfs_header_generation(buf);
4110	int was_dirty;
4111
4112#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4113	/*
4114	 * This is a fast path so only do this check if we have sanity tests
4115	 * enabled.  Normal people shouldn't be using unmapped buffers as dirty
4116	 * outside of the sanity tests.
4117	 */
4118	if (unlikely(test_bit(EXTENT_BUFFER_UNMAPPED, &buf->bflags)))
4119		return;
4120#endif
4121	root = BTRFS_I(buf->pages[0]->mapping->host)->root;
4122	fs_info = root->fs_info;
4123	btrfs_assert_tree_locked(buf);
4124	if (transid != fs_info->generation)
4125		WARN(1, KERN_CRIT "btrfs transid mismatch buffer %llu, found %llu running %llu\n",
4126			buf->start, transid, fs_info->generation);
 
4127	was_dirty = set_extent_buffer_dirty(buf);
4128	if (!was_dirty)
4129		percpu_counter_add_batch(&fs_info->dirty_metadata_bytes,
4130					 buf->len,
4131					 fs_info->dirty_metadata_batch);
4132#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
4133	/*
4134	 * Since btrfs_mark_buffer_dirty() can be called with item pointer set
4135	 * but item data not updated.
4136	 * So here we should only check item pointers, not item data.
4137	 */
4138	if (btrfs_header_level(buf) == 0 &&
4139	    btrfs_check_leaf_relaxed(buf)) {
4140		btrfs_print_leaf(buf);
4141		ASSERT(0);
4142	}
4143#endif
4144}
4145
4146static void __btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info,
4147					int flush_delayed)
4148{
4149	/*
4150	 * looks as though older kernels can get into trouble with
4151	 * this code, they end up stuck in balance_dirty_pages forever
4152	 */
4153	int ret;
4154
4155	if (current->flags & PF_MEMALLOC)
4156		return;
4157
4158	if (flush_delayed)
4159		btrfs_balance_delayed_items(fs_info);
4160
4161	ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
4162				     BTRFS_DIRTY_METADATA_THRESH,
4163				     fs_info->dirty_metadata_batch);
4164	if (ret > 0) {
4165		balance_dirty_pages_ratelimited(fs_info->btree_inode->i_mapping);
 
4166	}
 
 
 
 
 
 
4167}
4168
4169void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info)
4170{
4171	__btrfs_btree_balance_dirty(fs_info, 1);
4172}
4173
4174void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info)
4175{
4176	__btrfs_btree_balance_dirty(fs_info, 0);
 
4177}
4178
4179int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level,
4180		      struct btrfs_key *first_key)
4181{
4182	return btree_read_extent_buffer_pages(buf, parent_transid,
4183					      level, first_key);
 
 
4184}
4185
4186static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info)
4187{
 
 
 
 
 
 
 
4188	/* cleanup FS via transaction */
4189	btrfs_cleanup_transaction(fs_info);
 
4190
4191	mutex_lock(&fs_info->cleaner_mutex);
4192	btrfs_run_delayed_iputs(fs_info);
4193	mutex_unlock(&fs_info->cleaner_mutex);
 
 
 
 
 
 
 
 
 
 
 
 
4194
4195	down_write(&fs_info->cleanup_work_sem);
4196	up_write(&fs_info->cleanup_work_sem);
 
 
 
 
 
 
 
 
4197}
4198
4199static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
4200{
4201	struct btrfs_ordered_extent *ordered;
4202
4203	spin_lock(&root->ordered_extent_lock);
4204	/*
4205	 * This will just short circuit the ordered completion stuff which will
4206	 * make sure the ordered extent gets properly cleaned up.
4207	 */
4208	list_for_each_entry(ordered, &root->ordered_extents,
4209			    root_extent_list)
4210		set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
4211	spin_unlock(&root->ordered_extent_lock);
4212}
4213
4214static void btrfs_destroy_all_ordered_extents(struct btrfs_fs_info *fs_info)
4215{
4216	struct btrfs_root *root;
4217	struct list_head splice;
4218
4219	INIT_LIST_HEAD(&splice);
4220
4221	spin_lock(&fs_info->ordered_root_lock);
4222	list_splice_init(&fs_info->ordered_roots, &splice);
4223	while (!list_empty(&splice)) {
4224		root = list_first_entry(&splice, struct btrfs_root,
4225					ordered_root);
4226		list_move_tail(&root->ordered_root,
4227			       &fs_info->ordered_roots);
4228
4229		spin_unlock(&fs_info->ordered_root_lock);
4230		btrfs_destroy_ordered_extents(root);
4231
4232		cond_resched();
4233		spin_lock(&fs_info->ordered_root_lock);
4234	}
4235	spin_unlock(&fs_info->ordered_root_lock);
4236
4237	/*
4238	 * We need this here because if we've been flipped read-only we won't
4239	 * get sync() from the umount, so we need to make sure any ordered
4240	 * extents that haven't had their dirty pages IO start writeout yet
4241	 * actually get run and error out properly.
4242	 */
4243	btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
4244}
4245
4246static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
4247				      struct btrfs_fs_info *fs_info)
4248{
4249	struct rb_node *node;
4250	struct btrfs_delayed_ref_root *delayed_refs;
4251	struct btrfs_delayed_ref_node *ref;
4252	int ret = 0;
4253
4254	delayed_refs = &trans->delayed_refs;
4255
4256	spin_lock(&delayed_refs->lock);
4257	if (atomic_read(&delayed_refs->num_entries) == 0) {
4258		spin_unlock(&delayed_refs->lock);
4259		btrfs_info(fs_info, "delayed_refs has NO entry");
4260		return ret;
4261	}
4262
4263	while ((node = rb_first_cached(&delayed_refs->href_root)) != NULL) {
4264		struct btrfs_delayed_ref_head *head;
4265		struct rb_node *n;
4266		bool pin_bytes = false;
4267
4268		head = rb_entry(node, struct btrfs_delayed_ref_head,
4269				href_node);
4270		if (btrfs_delayed_ref_lock(delayed_refs, head))
 
 
 
 
 
 
 
4271			continue;
4272
4273		spin_lock(&head->lock);
4274		while ((n = rb_first_cached(&head->ref_tree)) != NULL) {
4275			ref = rb_entry(n, struct btrfs_delayed_ref_node,
4276				       ref_node);
4277			ref->in_tree = 0;
4278			rb_erase_cached(&ref->ref_node, &head->ref_tree);
4279			RB_CLEAR_NODE(&ref->ref_node);
4280			if (!list_empty(&ref->add_list))
4281				list_del(&ref->add_list);
4282			atomic_dec(&delayed_refs->num_entries);
4283			btrfs_put_delayed_ref(ref);
4284		}
4285		if (head->must_insert_reserved)
4286			pin_bytes = true;
4287		btrfs_free_delayed_extent_op(head->extent_op);
4288		btrfs_delete_ref_head(delayed_refs, head);
 
 
 
 
 
4289		spin_unlock(&head->lock);
4290		spin_unlock(&delayed_refs->lock);
4291		mutex_unlock(&head->mutex);
4292
4293		if (pin_bytes)
4294			btrfs_pin_extent(fs_info, head->bytenr,
4295					 head->num_bytes, 1);
4296		btrfs_cleanup_ref_head_accounting(fs_info, delayed_refs, head);
4297		btrfs_put_delayed_ref_head(head);
4298		cond_resched();
4299		spin_lock(&delayed_refs->lock);
4300	}
4301
4302	spin_unlock(&delayed_refs->lock);
4303
4304	return ret;
4305}
4306
4307static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
4308{
4309	struct btrfs_inode *btrfs_inode;
4310	struct list_head splice;
4311
4312	INIT_LIST_HEAD(&splice);
4313
4314	spin_lock(&root->delalloc_lock);
4315	list_splice_init(&root->delalloc_inodes, &splice);
4316
4317	while (!list_empty(&splice)) {
4318		struct inode *inode = NULL;
4319		btrfs_inode = list_first_entry(&splice, struct btrfs_inode,
4320					       delalloc_inodes);
4321		__btrfs_del_delalloc_inode(root, btrfs_inode);
 
 
 
4322		spin_unlock(&root->delalloc_lock);
4323
4324		/*
4325		 * Make sure we get a live inode and that it'll not disappear
4326		 * meanwhile.
4327		 */
4328		inode = igrab(&btrfs_inode->vfs_inode);
4329		if (inode) {
4330			invalidate_inode_pages2(inode->i_mapping);
4331			iput(inode);
4332		}
4333		spin_lock(&root->delalloc_lock);
4334	}
 
4335	spin_unlock(&root->delalloc_lock);
4336}
4337
4338static void btrfs_destroy_all_delalloc_inodes(struct btrfs_fs_info *fs_info)
4339{
4340	struct btrfs_root *root;
4341	struct list_head splice;
4342
4343	INIT_LIST_HEAD(&splice);
4344
4345	spin_lock(&fs_info->delalloc_root_lock);
4346	list_splice_init(&fs_info->delalloc_roots, &splice);
4347	while (!list_empty(&splice)) {
4348		root = list_first_entry(&splice, struct btrfs_root,
4349					 delalloc_root);
 
4350		root = btrfs_grab_fs_root(root);
4351		BUG_ON(!root);
4352		spin_unlock(&fs_info->delalloc_root_lock);
4353
4354		btrfs_destroy_delalloc_inodes(root);
4355		btrfs_put_fs_root(root);
4356
4357		spin_lock(&fs_info->delalloc_root_lock);
4358	}
4359	spin_unlock(&fs_info->delalloc_root_lock);
4360}
4361
4362static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
4363					struct extent_io_tree *dirty_pages,
4364					int mark)
4365{
4366	int ret;
4367	struct extent_buffer *eb;
4368	u64 start = 0;
4369	u64 end;
4370
4371	while (1) {
4372		ret = find_first_extent_bit(dirty_pages, start, &start, &end,
4373					    mark, NULL);
4374		if (ret)
4375			break;
4376
4377		clear_extent_bits(dirty_pages, start, end, mark);
4378		while (start <= end) {
4379			eb = find_extent_buffer(fs_info, start);
4380			start += fs_info->nodesize;
 
4381			if (!eb)
4382				continue;
4383			wait_on_extent_buffer_writeback(eb);
4384
4385			if (test_and_clear_bit(EXTENT_BUFFER_DIRTY,
4386					       &eb->bflags))
4387				clear_extent_buffer_dirty(eb);
4388			free_extent_buffer_stale(eb);
4389		}
4390	}
4391
4392	return ret;
4393}
4394
4395static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
4396				       struct extent_io_tree *pinned_extents)
4397{
4398	struct extent_io_tree *unpin;
4399	u64 start;
4400	u64 end;
4401	int ret;
4402	bool loop = true;
4403
4404	unpin = pinned_extents;
4405again:
4406	while (1) {
4407		struct extent_state *cached_state = NULL;
4408
4409		/*
4410		 * The btrfs_finish_extent_commit() may get the same range as
4411		 * ours between find_first_extent_bit and clear_extent_dirty.
4412		 * Hence, hold the unused_bg_unpin_mutex to avoid double unpin
4413		 * the same extent range.
4414		 */
4415		mutex_lock(&fs_info->unused_bg_unpin_mutex);
4416		ret = find_first_extent_bit(unpin, 0, &start, &end,
4417					    EXTENT_DIRTY, &cached_state);
4418		if (ret) {
4419			mutex_unlock(&fs_info->unused_bg_unpin_mutex);
4420			break;
4421		}
4422
4423		clear_extent_dirty(unpin, start, end, &cached_state);
4424		free_extent_state(cached_state);
4425		btrfs_error_unpin_extent_range(fs_info, start, end);
4426		mutex_unlock(&fs_info->unused_bg_unpin_mutex);
 
 
 
 
4427		cond_resched();
4428	}
4429
4430	if (loop) {
4431		if (unpin == &fs_info->freed_extents[0])
4432			unpin = &fs_info->freed_extents[1];
4433		else
4434			unpin = &fs_info->freed_extents[0];
4435		loop = false;
4436		goto again;
4437	}
4438
4439	return 0;
4440}
4441
4442static void btrfs_cleanup_bg_io(struct btrfs_block_group_cache *cache)
4443{
4444	struct inode *inode;
4445
4446	inode = cache->io_ctl.inode;
4447	if (inode) {
4448		invalidate_inode_pages2(inode->i_mapping);
4449		BTRFS_I(inode)->generation = 0;
4450		cache->io_ctl.inode = NULL;
4451		iput(inode);
4452	}
4453	btrfs_put_block_group(cache);
4454}
4455
4456void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *cur_trans,
4457			     struct btrfs_fs_info *fs_info)
4458{
4459	struct btrfs_block_group_cache *cache;
4460
4461	spin_lock(&cur_trans->dirty_bgs_lock);
4462	while (!list_empty(&cur_trans->dirty_bgs)) {
4463		cache = list_first_entry(&cur_trans->dirty_bgs,
4464					 struct btrfs_block_group_cache,
4465					 dirty_list);
4466
4467		if (!list_empty(&cache->io_list)) {
4468			spin_unlock(&cur_trans->dirty_bgs_lock);
4469			list_del_init(&cache->io_list);
4470			btrfs_cleanup_bg_io(cache);
4471			spin_lock(&cur_trans->dirty_bgs_lock);
4472		}
4473
4474		list_del_init(&cache->dirty_list);
4475		spin_lock(&cache->lock);
4476		cache->disk_cache_state = BTRFS_DC_ERROR;
4477		spin_unlock(&cache->lock);
4478
4479		spin_unlock(&cur_trans->dirty_bgs_lock);
4480		btrfs_put_block_group(cache);
4481		btrfs_delayed_refs_rsv_release(fs_info, 1);
4482		spin_lock(&cur_trans->dirty_bgs_lock);
4483	}
4484	spin_unlock(&cur_trans->dirty_bgs_lock);
4485
4486	/*
4487	 * Refer to the definition of io_bgs member for details why it's safe
4488	 * to use it without any locking
4489	 */
4490	while (!list_empty(&cur_trans->io_bgs)) {
4491		cache = list_first_entry(&cur_trans->io_bgs,
4492					 struct btrfs_block_group_cache,
4493					 io_list);
4494
4495		list_del_init(&cache->io_list);
4496		spin_lock(&cache->lock);
4497		cache->disk_cache_state = BTRFS_DC_ERROR;
4498		spin_unlock(&cache->lock);
4499		btrfs_cleanup_bg_io(cache);
4500	}
4501}
4502
4503void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
4504				   struct btrfs_fs_info *fs_info)
4505{
4506	struct btrfs_device *dev, *tmp;
4507
4508	btrfs_cleanup_dirty_bgs(cur_trans, fs_info);
4509	ASSERT(list_empty(&cur_trans->dirty_bgs));
4510	ASSERT(list_empty(&cur_trans->io_bgs));
4511
4512	list_for_each_entry_safe(dev, tmp, &cur_trans->dev_update_list,
4513				 post_commit_list) {
4514		list_del_init(&dev->post_commit_list);
4515	}
4516
4517	btrfs_destroy_delayed_refs(cur_trans, fs_info);
4518
4519	cur_trans->state = TRANS_STATE_COMMIT_START;
4520	wake_up(&fs_info->transaction_blocked_wait);
4521
4522	cur_trans->state = TRANS_STATE_UNBLOCKED;
4523	wake_up(&fs_info->transaction_wait);
4524
4525	btrfs_destroy_delayed_inodes(fs_info);
4526	btrfs_assert_delayed_root_empty(fs_info);
4527
4528	btrfs_destroy_marked_extents(fs_info, &cur_trans->dirty_pages,
4529				     EXTENT_DIRTY);
4530	btrfs_destroy_pinned_extent(fs_info,
4531				    fs_info->pinned_extents);
4532
4533	cur_trans->state =TRANS_STATE_COMPLETED;
4534	wake_up(&cur_trans->commit_wait);
 
 
 
 
 
4535}
4536
4537static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info)
4538{
4539	struct btrfs_transaction *t;
4540
4541	mutex_lock(&fs_info->transaction_kthread_mutex);
4542
4543	spin_lock(&fs_info->trans_lock);
4544	while (!list_empty(&fs_info->trans_list)) {
4545		t = list_first_entry(&fs_info->trans_list,
4546				     struct btrfs_transaction, list);
4547		if (t->state >= TRANS_STATE_COMMIT_START) {
4548			refcount_inc(&t->use_count);
4549			spin_unlock(&fs_info->trans_lock);
4550			btrfs_wait_for_commit(fs_info, t->transid);
4551			btrfs_put_transaction(t);
4552			spin_lock(&fs_info->trans_lock);
4553			continue;
4554		}
4555		if (t == fs_info->running_transaction) {
4556			t->state = TRANS_STATE_COMMIT_DOING;
4557			spin_unlock(&fs_info->trans_lock);
4558			/*
4559			 * We wait for 0 num_writers since we don't hold a trans
4560			 * handle open currently for this transaction.
4561			 */
4562			wait_event(t->writer_wait,
4563				   atomic_read(&t->num_writers) == 0);
4564		} else {
4565			spin_unlock(&fs_info->trans_lock);
4566		}
4567		btrfs_cleanup_one_transaction(t, fs_info);
4568
4569		spin_lock(&fs_info->trans_lock);
4570		if (t == fs_info->running_transaction)
4571			fs_info->running_transaction = NULL;
4572		list_del_init(&t->list);
4573		spin_unlock(&fs_info->trans_lock);
4574
4575		btrfs_put_transaction(t);
4576		trace_btrfs_transaction_commit(fs_info->tree_root);
4577		spin_lock(&fs_info->trans_lock);
4578	}
4579	spin_unlock(&fs_info->trans_lock);
4580	btrfs_destroy_all_ordered_extents(fs_info);
4581	btrfs_destroy_delayed_inodes(fs_info);
4582	btrfs_assert_delayed_root_empty(fs_info);
4583	btrfs_destroy_pinned_extent(fs_info, fs_info->pinned_extents);
4584	btrfs_destroy_all_delalloc_inodes(fs_info);
4585	mutex_unlock(&fs_info->transaction_kthread_mutex);
4586
4587	return 0;
4588}
4589
4590static const struct extent_io_ops btree_extent_io_ops = {
4591	/* mandatory callbacks */
4592	.submit_bio_hook = btree_submit_bio_hook,
4593	.readpage_end_io_hook = btree_readpage_end_io_hook,
 
 
 
 
4594};
v3.15
 
   1/*
   2 * Copyright (C) 2007 Oracle.  All rights reserved.
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of the GNU General Public
   6 * License v2 as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful,
   9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11 * General Public License for more details.
  12 *
  13 * You should have received a copy of the GNU General Public
  14 * License along with this program; if not, write to the
  15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16 * Boston, MA 021110-1307, USA.
  17 */
  18
  19#include <linux/fs.h>
  20#include <linux/blkdev.h>
  21#include <linux/scatterlist.h>
  22#include <linux/swap.h>
  23#include <linux/radix-tree.h>
  24#include <linux/writeback.h>
  25#include <linux/buffer_head.h>
  26#include <linux/workqueue.h>
  27#include <linux/kthread.h>
  28#include <linux/freezer.h>
  29#include <linux/slab.h>
  30#include <linux/migrate.h>
  31#include <linux/ratelimit.h>
  32#include <linux/uuid.h>
  33#include <linux/semaphore.h>
 
 
 
  34#include <asm/unaligned.h>
 
  35#include "ctree.h"
  36#include "disk-io.h"
  37#include "hash.h"
  38#include "transaction.h"
  39#include "btrfs_inode.h"
  40#include "volumes.h"
  41#include "print-tree.h"
  42#include "async-thread.h"
  43#include "locking.h"
  44#include "tree-log.h"
  45#include "free-space-cache.h"
 
  46#include "inode-map.h"
  47#include "check-integrity.h"
  48#include "rcu-string.h"
  49#include "dev-replace.h"
  50#include "raid56.h"
  51#include "sysfs.h"
 
 
 
 
 
 
 
 
 
 
 
 
  52
  53#ifdef CONFIG_X86
  54#include <asm/cpufeature.h>
  55#endif
  56
  57static struct extent_io_ops btree_extent_io_ops;
  58static void end_workqueue_fn(struct btrfs_work *work);
  59static void free_fs_root(struct btrfs_root *root);
  60static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
  61				    int read_only);
  62static void btrfs_destroy_ordered_operations(struct btrfs_transaction *t,
  63					     struct btrfs_root *root);
  64static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
  65static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
  66				      struct btrfs_root *root);
  67static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
  68static int btrfs_destroy_marked_extents(struct btrfs_root *root,
  69					struct extent_io_tree *dirty_pages,
  70					int mark);
  71static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
  72				       struct extent_io_tree *pinned_extents);
  73static int btrfs_cleanup_transaction(struct btrfs_root *root);
  74static void btrfs_error_commit_super(struct btrfs_root *root);
  75
  76/*
  77 * end_io_wq structs are used to do processing in task context when an IO is
  78 * complete.  This is used during reads to verify checksums, and it is used
  79 * by writes to insert metadata for new file extents after IO is complete.
  80 */
  81struct end_io_wq {
  82	struct bio *bio;
  83	bio_end_io_t *end_io;
  84	void *private;
  85	struct btrfs_fs_info *info;
  86	int error;
  87	int metadata;
  88	struct list_head list;
  89	struct btrfs_work work;
  90};
  91
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  92/*
  93 * async submit bios are used to offload expensive checksumming
  94 * onto the worker threads.  They checksum file and metadata bios
  95 * just before they are sent down the IO stack.
  96 */
  97struct async_submit_bio {
  98	struct inode *inode;
  99	struct bio *bio;
 100	struct list_head list;
 101	extent_submit_bio_hook_t *submit_bio_start;
 102	extent_submit_bio_hook_t *submit_bio_done;
 103	int rw;
 104	int mirror_num;
 105	unsigned long bio_flags;
 106	/*
 107	 * bio_offset is optional, can be used if the pages in the bio
 108	 * can't tell us where in the file the bio should go
 109	 */
 110	u64 bio_offset;
 111	struct btrfs_work work;
 112	int error;
 113};
 114
 115/*
 116 * Lockdep class keys for extent_buffer->lock's in this root.  For a given
 117 * eb, the lockdep key is determined by the btrfs_root it belongs to and
 118 * the level the eb occupies in the tree.
 119 *
 120 * Different roots are used for different purposes and may nest inside each
 121 * other and they require separate keysets.  As lockdep keys should be
 122 * static, assign keysets according to the purpose of the root as indicated
 123 * by btrfs_root->objectid.  This ensures that all special purpose roots
 124 * have separate keysets.
 125 *
 126 * Lock-nesting across peer nodes is always done with the immediate parent
 127 * node locked thus preventing deadlock.  As lockdep doesn't know this, use
 128 * subclass to avoid triggering lockdep warning in such cases.
 129 *
 130 * The key is set by the readpage_end_io_hook after the buffer has passed
 131 * csum validation but before the pages are unlocked.  It is also set by
 132 * btrfs_init_new_buffer on freshly allocated blocks.
 133 *
 134 * We also add a check to make sure the highest level of the tree is the
 135 * same as our lockdep setup here.  If BTRFS_MAX_LEVEL changes, this code
 136 * needs update as well.
 137 */
 138#ifdef CONFIG_DEBUG_LOCK_ALLOC
 139# if BTRFS_MAX_LEVEL != 8
 140#  error
 141# endif
 142
 143static struct btrfs_lockdep_keyset {
 144	u64			id;		/* root objectid */
 145	const char		*name_stem;	/* lock name stem */
 146	char			names[BTRFS_MAX_LEVEL + 1][20];
 147	struct lock_class_key	keys[BTRFS_MAX_LEVEL + 1];
 148} btrfs_lockdep_keysets[] = {
 149	{ .id = BTRFS_ROOT_TREE_OBJECTID,	.name_stem = "root"	},
 150	{ .id = BTRFS_EXTENT_TREE_OBJECTID,	.name_stem = "extent"	},
 151	{ .id = BTRFS_CHUNK_TREE_OBJECTID,	.name_stem = "chunk"	},
 152	{ .id = BTRFS_DEV_TREE_OBJECTID,	.name_stem = "dev"	},
 153	{ .id = BTRFS_FS_TREE_OBJECTID,		.name_stem = "fs"	},
 154	{ .id = BTRFS_CSUM_TREE_OBJECTID,	.name_stem = "csum"	},
 155	{ .id = BTRFS_QUOTA_TREE_OBJECTID,	.name_stem = "quota"	},
 156	{ .id = BTRFS_TREE_LOG_OBJECTID,	.name_stem = "log"	},
 157	{ .id = BTRFS_TREE_RELOC_OBJECTID,	.name_stem = "treloc"	},
 158	{ .id = BTRFS_DATA_RELOC_TREE_OBJECTID,	.name_stem = "dreloc"	},
 159	{ .id = BTRFS_UUID_TREE_OBJECTID,	.name_stem = "uuid"	},
 
 160	{ .id = 0,				.name_stem = "tree"	},
 161};
 162
 163void __init btrfs_init_lockdep(void)
 164{
 165	int i, j;
 166
 167	/* initialize lockdep class names */
 168	for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) {
 169		struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i];
 170
 171		for (j = 0; j < ARRAY_SIZE(ks->names); j++)
 172			snprintf(ks->names[j], sizeof(ks->names[j]),
 173				 "btrfs-%s-%02d", ks->name_stem, j);
 174	}
 175}
 176
 177void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
 178				    int level)
 179{
 180	struct btrfs_lockdep_keyset *ks;
 181
 182	BUG_ON(level >= ARRAY_SIZE(ks->keys));
 183
 184	/* find the matching keyset, id 0 is the default entry */
 185	for (ks = btrfs_lockdep_keysets; ks->id; ks++)
 186		if (ks->id == objectid)
 187			break;
 188
 189	lockdep_set_class_and_name(&eb->lock,
 190				   &ks->keys[level], ks->names[level]);
 191}
 192
 193#endif
 194
 195/*
 196 * extents on the btree inode are pretty simple, there's one extent
 197 * that covers the entire device
 198 */
 199static struct extent_map *btree_get_extent(struct inode *inode,
 200		struct page *page, size_t pg_offset, u64 start, u64 len,
 201		int create)
 202{
 203	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 
 204	struct extent_map *em;
 205	int ret;
 206
 207	read_lock(&em_tree->lock);
 208	em = lookup_extent_mapping(em_tree, start, len);
 209	if (em) {
 210		em->bdev =
 211			BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
 212		read_unlock(&em_tree->lock);
 213		goto out;
 214	}
 215	read_unlock(&em_tree->lock);
 216
 217	em = alloc_extent_map();
 218	if (!em) {
 219		em = ERR_PTR(-ENOMEM);
 220		goto out;
 221	}
 222	em->start = 0;
 223	em->len = (u64)-1;
 224	em->block_len = (u64)-1;
 225	em->block_start = 0;
 226	em->bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
 227
 228	write_lock(&em_tree->lock);
 229	ret = add_extent_mapping(em_tree, em, 0);
 230	if (ret == -EEXIST) {
 231		free_extent_map(em);
 232		em = lookup_extent_mapping(em_tree, start, len);
 233		if (!em)
 234			em = ERR_PTR(-EIO);
 235	} else if (ret) {
 236		free_extent_map(em);
 237		em = ERR_PTR(ret);
 238	}
 239	write_unlock(&em_tree->lock);
 240
 241out:
 242	return em;
 243}
 244
 245u32 btrfs_csum_data(char *data, u32 seed, size_t len)
 246{
 247	return btrfs_crc32c(seed, data, len);
 248}
 249
 250void btrfs_csum_final(u32 crc, char *result)
 251{
 252	put_unaligned_le32(~crc, result);
 253}
 254
 255/*
 256 * compute the csum for a btree block, and either verify it or write it
 257 * into the csum field of the block.
 
 258 */
 259static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 260			   int verify)
 261{
 262	u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
 263	char *result = NULL;
 264	unsigned long len;
 265	unsigned long cur_len;
 266	unsigned long offset = BTRFS_CSUM_SIZE;
 267	char *kaddr;
 268	unsigned long map_start;
 269	unsigned long map_len;
 270	int err;
 271	u32 crc = ~(u32)0;
 272	unsigned long inline_result;
 
 273
 274	len = buf->len - offset;
 
 275	while (len > 0) {
 
 
 
 
 
 
 276		err = map_private_extent_buffer(buf, offset, 32,
 277					&kaddr, &map_start, &map_len);
 278		if (err)
 279			return 1;
 280		cur_len = min(len, map_len - (offset - map_start));
 281		crc = btrfs_csum_data(kaddr + offset - map_start,
 282				      crc, cur_len);
 283		len -= cur_len;
 284		offset += cur_len;
 285	}
 286	if (csum_size > sizeof(inline_result)) {
 287		result = kzalloc(csum_size * sizeof(char), GFP_NOFS);
 288		if (!result)
 289			return 1;
 290	} else {
 291		result = (char *)&inline_result;
 292	}
 293
 294	btrfs_csum_final(crc, result);
 295
 296	if (verify) {
 297		if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
 298			u32 val;
 299			u32 found = 0;
 300			memcpy(&found, result, csum_size);
 301
 302			read_extent_buffer(buf, &val, 0, csum_size);
 303			printk_ratelimited(KERN_INFO
 304				"BTRFS: %s checksum verify failed on %llu wanted %X found %X "
 305				"level %d\n",
 306				root->fs_info->sb->s_id, buf->start,
 307				val, found, btrfs_header_level(buf));
 308			if (result != (char *)&inline_result)
 309				kfree(result);
 310			return 1;
 311		}
 312	} else {
 313		write_extent_buffer(buf, result, 0, csum_size);
 314	}
 315	if (result != (char *)&inline_result)
 316		kfree(result);
 317	return 0;
 318}
 319
 320/*
 321 * we can't consider a given block up to date unless the transid of the
 322 * block matches the transid in the parent node's pointer.  This is how we
 323 * detect blocks that either didn't get written at all or got written
 324 * in the wrong place.
 325 */
 326static int verify_parent_transid(struct extent_io_tree *io_tree,
 327				 struct extent_buffer *eb, u64 parent_transid,
 328				 int atomic)
 329{
 330	struct extent_state *cached_state = NULL;
 331	int ret;
 332	bool need_lock = (current->journal_info ==
 333			  (void *)BTRFS_SEND_TRANS_STUB);
 334
 335	if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 336		return 0;
 337
 338	if (atomic)
 339		return -EAGAIN;
 340
 341	if (need_lock) {
 342		btrfs_tree_read_lock(eb);
 343		btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
 344	}
 345
 346	lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
 347			 0, &cached_state);
 348	if (extent_buffer_uptodate(eb) &&
 349	    btrfs_header_generation(eb) == parent_transid) {
 350		ret = 0;
 351		goto out;
 352	}
 353	printk_ratelimited("parent transid verify failed on %llu wanted %llu "
 354		       "found %llu\n",
 355		       eb->start, parent_transid, btrfs_header_generation(eb));
 
 356	ret = 1;
 357
 358	/*
 359	 * Things reading via commit roots that don't have normal protection,
 360	 * like send, can have a really old block in cache that may point at a
 361	 * block that has been free'd and re-allocated.  So don't clear uptodate
 362	 * if we find an eb that is under IO (dirty/writeback) because we could
 363	 * end up reading in the stale data and then writing it back out and
 364	 * making everybody very sad.
 365	 */
 366	if (!extent_buffer_under_io(eb))
 367		clear_extent_buffer_uptodate(eb);
 368out:
 369	unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
 370			     &cached_state, GFP_NOFS);
 371	btrfs_tree_read_unlock_blocking(eb);
 
 372	return ret;
 373}
 374
 
 
 
 
 
 
 
 
 
 
 375/*
 376 * Return 0 if the superblock checksum type matches the checksum value of that
 377 * algorithm. Pass the raw disk superblock data.
 378 */
 379static int btrfs_check_super_csum(char *raw_disk_sb)
 
 380{
 381	struct btrfs_super_block *disk_sb =
 382		(struct btrfs_super_block *)raw_disk_sb;
 383	u16 csum_type = btrfs_super_csum_type(disk_sb);
 384	int ret = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 385
 386	if (csum_type == BTRFS_CSUM_TYPE_CRC32) {
 387		u32 crc = ~(u32)0;
 388		const int csum_size = sizeof(crc);
 389		char result[csum_size];
 390
 391		/*
 392		 * The super_block structure does not span the whole
 393		 * BTRFS_SUPER_INFO_SIZE range, we expect that the unused space
 394		 * is filled with zeros and is included in the checkum.
 395		 */
 396		crc = btrfs_csum_data(raw_disk_sb + BTRFS_CSUM_SIZE,
 397				crc, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
 398		btrfs_csum_final(crc, result);
 399
 400		if (memcmp(raw_disk_sb, result, csum_size))
 401			ret = 1;
 
 
 
 
 
 402
 403		if (ret && btrfs_super_generation(disk_sb) < 10) {
 404			printk(KERN_WARNING
 405				"BTRFS: super block crcs don't match, older mkfs detected\n");
 406			ret = 0;
 407		}
 
 
 
 408	}
 409
 410	if (csum_type >= ARRAY_SIZE(btrfs_csum_sizes)) {
 411		printk(KERN_ERR "BTRFS: unsupported checksum algorithm %u\n",
 412				csum_type);
 413		ret = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 414	}
 415
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 416	return ret;
 417}
 418
 419/*
 420 * helper to read a given tree block, doing retries as required when
 421 * the checksums don't match and we have alternate mirrors to try.
 
 
 
 
 422 */
 423static int btree_read_extent_buffer_pages(struct btrfs_root *root,
 424					  struct extent_buffer *eb,
 425					  u64 start, u64 parent_transid)
 426{
 
 427	struct extent_io_tree *io_tree;
 428	int failed = 0;
 429	int ret;
 430	int num_copies = 0;
 431	int mirror_num = 0;
 432	int failed_mirror = 0;
 433
 434	clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 435	io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
 436	while (1) {
 437		ret = read_extent_buffer_pages(io_tree, eb, start,
 438					       WAIT_COMPLETE,
 439					       btree_get_extent, mirror_num);
 440		if (!ret) {
 441			if (!verify_parent_transid(io_tree, eb,
 442						   parent_transid, 0))
 
 
 
 
 
 443				break;
 444			else
 445				ret = -EIO;
 446		}
 447
 448		/*
 449		 * This buffer's crc is fine, but its contents are corrupted, so
 450		 * there is no reason to read the other copies, they won't be
 451		 * any less wrong.
 452		 */
 453		if (test_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags))
 454			break;
 455
 456		num_copies = btrfs_num_copies(root->fs_info,
 457					      eb->start, eb->len);
 458		if (num_copies == 1)
 459			break;
 460
 461		if (!failed_mirror) {
 462			failed = 1;
 463			failed_mirror = eb->read_mirror;
 464		}
 465
 466		mirror_num++;
 467		if (mirror_num == failed_mirror)
 468			mirror_num++;
 469
 470		if (mirror_num > num_copies)
 471			break;
 472	}
 473
 474	if (failed && !ret && failed_mirror)
 475		repair_eb_io_failure(root, eb, failed_mirror);
 476
 477	return ret;
 478}
 479
 480/*
 481 * checksum a dirty tree block before IO.  This has extra checks to make sure
 482 * we only fill in the checksum field in the first page of a multi-page block
 483 */
 484
 485static int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
 486{
 487	u64 start = page_offset(page);
 488	u64 found_start;
 
 
 489	struct extent_buffer *eb;
 
 490
 491	eb = (struct extent_buffer *)page->private;
 492	if (page != eb->pages[0])
 493		return 0;
 
 494	found_start = btrfs_header_bytenr(eb);
 495	if (WARN_ON(found_start != start || !PageUptodate(page)))
 496		return 0;
 497	csum_tree_block(root, eb, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 498	return 0;
 499}
 500
 501static int check_tree_block_fsid(struct btrfs_root *root,
 502				 struct extent_buffer *eb)
 503{
 504	struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
 505	u8 fsid[BTRFS_UUID_SIZE];
 
 506	int ret = 1;
 507
 508	read_extent_buffer(eb, fsid, btrfs_header_fsid(), BTRFS_FSID_SIZE);
 509	while (fs_devices) {
 510		if (!memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE)) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 511			ret = 0;
 512			break;
 513		}
 514		fs_devices = fs_devices->seed;
 515	}
 516	return ret;
 517}
 518
 519#define CORRUPT(reason, eb, root, slot)				\
 520	btrfs_crit(root->fs_info, "corrupt leaf, %s: block=%llu,"	\
 521		   "root=%llu, slot=%d", reason,			\
 522	       btrfs_header_bytenr(eb),	root->objectid, slot)
 523
 524static noinline int check_leaf(struct btrfs_root *root,
 525			       struct extent_buffer *leaf)
 526{
 527	struct btrfs_key key;
 528	struct btrfs_key leaf_key;
 529	u32 nritems = btrfs_header_nritems(leaf);
 530	int slot;
 531
 532	if (nritems == 0)
 533		return 0;
 534
 535	/* Check the 0 item */
 536	if (btrfs_item_offset_nr(leaf, 0) + btrfs_item_size_nr(leaf, 0) !=
 537	    BTRFS_LEAF_DATA_SIZE(root)) {
 538		CORRUPT("invalid item offset size pair", leaf, root, 0);
 539		return -EIO;
 540	}
 541
 542	/*
 543	 * Check to make sure each items keys are in the correct order and their
 544	 * offsets make sense.  We only have to loop through nritems-1 because
 545	 * we check the current slot against the next slot, which verifies the
 546	 * next slot's offset+size makes sense and that the current's slot
 547	 * offset is correct.
 548	 */
 549	for (slot = 0; slot < nritems - 1; slot++) {
 550		btrfs_item_key_to_cpu(leaf, &leaf_key, slot);
 551		btrfs_item_key_to_cpu(leaf, &key, slot + 1);
 552
 553		/* Make sure the keys are in the right order */
 554		if (btrfs_comp_cpu_keys(&leaf_key, &key) >= 0) {
 555			CORRUPT("bad key order", leaf, root, slot);
 556			return -EIO;
 557		}
 558
 559		/*
 560		 * Make sure the offset and ends are right, remember that the
 561		 * item data starts at the end of the leaf and grows towards the
 562		 * front.
 563		 */
 564		if (btrfs_item_offset_nr(leaf, slot) !=
 565			btrfs_item_end_nr(leaf, slot + 1)) {
 566			CORRUPT("slot offset bad", leaf, root, slot);
 567			return -EIO;
 568		}
 569
 570		/*
 571		 * Check to make sure that we don't point outside of the leaf,
 572		 * just incase all the items are consistent to eachother, but
 573		 * all point outside of the leaf.
 574		 */
 575		if (btrfs_item_end_nr(leaf, slot) >
 576		    BTRFS_LEAF_DATA_SIZE(root)) {
 577			CORRUPT("slot end outside of leaf", leaf, root, slot);
 578			return -EIO;
 579		}
 580	}
 581
 582	return 0;
 583}
 584
 585static int btree_readpage_end_io_hook(struct btrfs_io_bio *io_bio,
 586				      u64 phy_offset, struct page *page,
 587				      u64 start, u64 end, int mirror)
 588{
 589	u64 found_start;
 590	int found_level;
 591	struct extent_buffer *eb;
 592	struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 
 
 593	int ret = 0;
 
 594	int reads_done;
 595
 596	if (!page->private)
 597		goto out;
 598
 599	eb = (struct extent_buffer *)page->private;
 600
 601	/* the pending IO might have been the only thing that kept this buffer
 602	 * in memory.  Make sure we have a ref for all this other checks
 603	 */
 604	extent_buffer_get(eb);
 605
 606	reads_done = atomic_dec_and_test(&eb->io_pages);
 607	if (!reads_done)
 608		goto err;
 609
 610	eb->read_mirror = mirror;
 611	if (test_bit(EXTENT_BUFFER_IOERR, &eb->bflags)) {
 612		ret = -EIO;
 613		goto err;
 614	}
 615
 616	found_start = btrfs_header_bytenr(eb);
 617	if (found_start != eb->start) {
 618		printk_ratelimited(KERN_INFO "BTRFS: bad tree block start "
 619			       "%llu %llu\n",
 620			       found_start, eb->start);
 621		ret = -EIO;
 622		goto err;
 623	}
 624	if (check_tree_block_fsid(root, eb)) {
 625		printk_ratelimited(KERN_INFO "BTRFS: bad fsid on block %llu\n",
 626			       eb->start);
 627		ret = -EIO;
 628		goto err;
 629	}
 630	found_level = btrfs_header_level(eb);
 631	if (found_level >= BTRFS_MAX_LEVEL) {
 632		btrfs_info(root->fs_info, "bad tree block level %d",
 633			   (int)btrfs_header_level(eb));
 634		ret = -EIO;
 635		goto err;
 636	}
 637
 638	btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb),
 639				       eb, found_level);
 640
 641	ret = csum_tree_block(root, eb, 1);
 642	if (ret) {
 643		ret = -EIO;
 
 
 
 
 
 
 
 
 
 
 
 
 
 644		goto err;
 645	}
 646
 647	/*
 648	 * If this is a leaf block and it is corrupt, set the corrupt bit so
 649	 * that we don't try and read the other copies of this block, just
 650	 * return -EIO.
 651	 */
 652	if (found_level == 0 && check_leaf(root, eb)) {
 653		set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
 654		ret = -EIO;
 655	}
 656
 
 
 
 657	if (!ret)
 658		set_extent_buffer_uptodate(eb);
 
 
 
 
 659err:
 660	if (reads_done &&
 661	    test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
 662		btree_readahead_hook(root, eb, eb->start, ret);
 663
 664	if (ret) {
 665		/*
 666		 * our io error hook is going to dec the io pages
 667		 * again, we have to make sure it has something
 668		 * to decrement
 669		 */
 670		atomic_inc(&eb->io_pages);
 671		clear_extent_buffer_uptodate(eb);
 672	}
 673	free_extent_buffer(eb);
 674out:
 675	return ret;
 676}
 677
 678static int btree_io_failed_hook(struct page *page, int failed_mirror)
 679{
 680	struct extent_buffer *eb;
 681	struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 682
 683	eb = (struct extent_buffer *)page->private;
 684	set_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
 685	eb->read_mirror = failed_mirror;
 686	atomic_dec(&eb->io_pages);
 687	if (test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
 688		btree_readahead_hook(root, eb, eb->start, -EIO);
 689	return -EIO;	/* we fixed nothing */
 690}
 691
 692static void end_workqueue_bio(struct bio *bio, int err)
 693{
 694	struct end_io_wq *end_io_wq = bio->bi_private;
 695	struct btrfs_fs_info *fs_info;
 
 
 696
 697	fs_info = end_io_wq->info;
 698	end_io_wq->error = err;
 699	btrfs_init_work(&end_io_wq->work, end_workqueue_fn, NULL, NULL);
 700
 701	if (bio->bi_rw & REQ_WRITE) {
 702		if (end_io_wq->metadata == BTRFS_WQ_ENDIO_METADATA)
 703			btrfs_queue_work(fs_info->endio_meta_write_workers,
 704					 &end_io_wq->work);
 705		else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_FREE_SPACE)
 706			btrfs_queue_work(fs_info->endio_freespace_worker,
 707					 &end_io_wq->work);
 708		else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56)
 709			btrfs_queue_work(fs_info->endio_raid56_workers,
 710					 &end_io_wq->work);
 711		else
 712			btrfs_queue_work(fs_info->endio_write_workers,
 713					 &end_io_wq->work);
 
 714	} else {
 715		if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56)
 716			btrfs_queue_work(fs_info->endio_raid56_workers,
 717					 &end_io_wq->work);
 718		else if (end_io_wq->metadata)
 719			btrfs_queue_work(fs_info->endio_meta_workers,
 720					 &end_io_wq->work);
 721		else
 722			btrfs_queue_work(fs_info->endio_workers,
 723					 &end_io_wq->work);
 
 
 
 
 
 724	}
 
 
 
 725}
 726
 727/*
 728 * For the metadata arg you want
 729 *
 730 * 0 - if data
 731 * 1 - if normal metadta
 732 * 2 - if writing to the free space cache area
 733 * 3 - raid parity work
 734 */
 735int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
 736			int metadata)
 737{
 738	struct end_io_wq *end_io_wq;
 739	end_io_wq = kmalloc(sizeof(*end_io_wq), GFP_NOFS);
 
 740	if (!end_io_wq)
 741		return -ENOMEM;
 742
 743	end_io_wq->private = bio->bi_private;
 744	end_io_wq->end_io = bio->bi_end_io;
 745	end_io_wq->info = info;
 746	end_io_wq->error = 0;
 747	end_io_wq->bio = bio;
 748	end_io_wq->metadata = metadata;
 749
 750	bio->bi_private = end_io_wq;
 751	bio->bi_end_io = end_workqueue_bio;
 752	return 0;
 753}
 754
 755unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info)
 756{
 757	unsigned long limit = min_t(unsigned long,
 758				    info->thread_pool_size,
 759				    info->fs_devices->open_devices);
 760	return 256 * limit;
 761}
 762
 763static void run_one_async_start(struct btrfs_work *work)
 764{
 765	struct async_submit_bio *async;
 766	int ret;
 767
 768	async = container_of(work, struct  async_submit_bio, work);
 769	ret = async->submit_bio_start(async->inode, async->rw, async->bio,
 770				      async->mirror_num, async->bio_flags,
 771				      async->bio_offset);
 772	if (ret)
 773		async->error = ret;
 774}
 775
 
 
 
 
 
 
 
 
 776static void run_one_async_done(struct btrfs_work *work)
 777{
 778	struct btrfs_fs_info *fs_info;
 779	struct async_submit_bio *async;
 780	int limit;
 
 781
 782	async = container_of(work, struct  async_submit_bio, work);
 783	fs_info = BTRFS_I(async->inode)->root->fs_info;
 784
 785	limit = btrfs_async_submit_limit(fs_info);
 786	limit = limit * 2 / 3;
 787
 788	if (atomic_dec_return(&fs_info->nr_async_submits) < limit &&
 789	    waitqueue_active(&fs_info->async_submit_wait))
 790		wake_up(&fs_info->async_submit_wait);
 791
 792	/* If an error occured we just want to clean up the bio and move on */
 793	if (async->error) {
 794		bio_endio(async->bio, async->error);
 795		return;
 796	}
 797
 798	async->submit_bio_done(async->inode, async->rw, async->bio,
 799			       async->mirror_num, async->bio_flags,
 800			       async->bio_offset);
 
 
 
 801}
 802
 803static void run_one_async_free(struct btrfs_work *work)
 804{
 805	struct async_submit_bio *async;
 806
 807	async = container_of(work, struct  async_submit_bio, work);
 808	kfree(async);
 809}
 810
 811int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
 812			int rw, struct bio *bio, int mirror_num,
 813			unsigned long bio_flags,
 814			u64 bio_offset,
 815			extent_submit_bio_hook_t *submit_bio_start,
 816			extent_submit_bio_hook_t *submit_bio_done)
 817{
 818	struct async_submit_bio *async;
 819
 820	async = kmalloc(sizeof(*async), GFP_NOFS);
 821	if (!async)
 822		return -ENOMEM;
 823
 824	async->inode = inode;
 825	async->rw = rw;
 826	async->bio = bio;
 827	async->mirror_num = mirror_num;
 828	async->submit_bio_start = submit_bio_start;
 829	async->submit_bio_done = submit_bio_done;
 830
 831	btrfs_init_work(&async->work, run_one_async_start,
 832			run_one_async_done, run_one_async_free);
 833
 834	async->bio_flags = bio_flags;
 835	async->bio_offset = bio_offset;
 836
 837	async->error = 0;
 838
 839	atomic_inc(&fs_info->nr_async_submits);
 840
 841	if (rw & REQ_SYNC)
 842		btrfs_set_work_high_priority(&async->work);
 843
 844	btrfs_queue_work(fs_info->workers, &async->work);
 845
 846	while (atomic_read(&fs_info->async_submit_draining) &&
 847	      atomic_read(&fs_info->nr_async_submits)) {
 848		wait_event(fs_info->async_submit_wait,
 849			   (atomic_read(&fs_info->nr_async_submits) == 0));
 850	}
 851
 852	return 0;
 853}
 854
 855static int btree_csum_one_bio(struct bio *bio)
 856{
 857	struct bio_vec *bvec;
 858	struct btrfs_root *root;
 859	int i, ret = 0;
 
 860
 861	bio_for_each_segment_all(bvec, bio, i) {
 
 862		root = BTRFS_I(bvec->bv_page->mapping->host)->root;
 863		ret = csum_dirty_buffer(root, bvec->bv_page);
 864		if (ret)
 865			break;
 866	}
 867
 868	return ret;
 869}
 870
 871static int __btree_submit_bio_start(struct inode *inode, int rw,
 872				    struct bio *bio, int mirror_num,
 873				    unsigned long bio_flags,
 874				    u64 bio_offset)
 875{
 876	/*
 877	 * when we're called for a write, we're already in the async
 878	 * submission context.  Just jump into btrfs_map_bio
 879	 */
 880	return btree_csum_one_bio(bio);
 881}
 882
 883static int __btree_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
 884				 int mirror_num, unsigned long bio_flags,
 885				 u64 bio_offset)
 886{
 887	int ret;
 888
 889	/*
 890	 * when we're called for a write, we're already in the async
 891	 * submission context.  Just jump into btrfs_map_bio
 892	 */
 893	ret = btrfs_map_bio(BTRFS_I(inode)->root, rw, bio, mirror_num, 1);
 894	if (ret)
 895		bio_endio(bio, ret);
 896	return ret;
 897}
 898
 899static int check_async_write(struct inode *inode, unsigned long bio_flags)
 900{
 901	if (bio_flags & EXTENT_BIO_TREE_LOG)
 902		return 0;
 903#ifdef CONFIG_X86
 904	if (cpu_has_xmm4_2)
 905		return 0;
 906#endif
 907	return 1;
 908}
 909
 910static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
 911				 int mirror_num, unsigned long bio_flags,
 912				 u64 bio_offset)
 913{
 914	int async = check_async_write(inode, bio_flags);
 915	int ret;
 
 916
 917	if (!(rw & REQ_WRITE)) {
 918		/*
 919		 * called for a read, do the setup so that checksum validation
 920		 * can happen in the async kernel threads
 921		 */
 922		ret = btrfs_bio_wq_end_io(BTRFS_I(inode)->root->fs_info,
 923					  bio, 1);
 924		if (ret)
 925			goto out_w_error;
 926		ret = btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
 927				    mirror_num, 0);
 928	} else if (!async) {
 929		ret = btree_csum_one_bio(bio);
 930		if (ret)
 931			goto out_w_error;
 932		ret = btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
 933				    mirror_num, 0);
 934	} else {
 935		/*
 936		 * kthread helpers are used to submit writes so that
 937		 * checksumming can happen in parallel across all CPUs
 938		 */
 939		ret = btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
 940					  inode, rw, bio, mirror_num, 0,
 941					  bio_offset,
 942					  __btree_submit_bio_start,
 943					  __btree_submit_bio_done);
 944	}
 945
 946	if (ret) {
 
 
 
 947out_w_error:
 948		bio_endio(bio, ret);
 949	}
 950	return ret;
 951}
 952
 953#ifdef CONFIG_MIGRATION
 954static int btree_migratepage(struct address_space *mapping,
 955			struct page *newpage, struct page *page,
 956			enum migrate_mode mode)
 957{
 958	/*
 959	 * we can't safely write a btree page from here,
 960	 * we haven't done the locking hook
 961	 */
 962	if (PageDirty(page))
 963		return -EAGAIN;
 964	/*
 965	 * Buffers may be managed in a filesystem specific way.
 966	 * We must have no buffers or drop them.
 967	 */
 968	if (page_has_private(page) &&
 969	    !try_to_release_page(page, GFP_KERNEL))
 970		return -EAGAIN;
 971	return migrate_page(mapping, newpage, page, mode);
 972}
 973#endif
 974
 975
 976static int btree_writepages(struct address_space *mapping,
 977			    struct writeback_control *wbc)
 978{
 979	struct btrfs_fs_info *fs_info;
 980	int ret;
 981
 982	if (wbc->sync_mode == WB_SYNC_NONE) {
 983
 984		if (wbc->for_kupdate)
 985			return 0;
 986
 987		fs_info = BTRFS_I(mapping->host)->root->fs_info;
 988		/* this is a bit racy, but that's ok */
 989		ret = percpu_counter_compare(&fs_info->dirty_metadata_bytes,
 990					     BTRFS_DIRTY_METADATA_THRESH);
 
 991		if (ret < 0)
 992			return 0;
 993	}
 994	return btree_write_cache_pages(mapping, wbc);
 995}
 996
 997static int btree_readpage(struct file *file, struct page *page)
 998{
 999	struct extent_io_tree *tree;
1000	tree = &BTRFS_I(page->mapping->host)->io_tree;
1001	return extent_read_full_page(tree, page, btree_get_extent, 0);
1002}
1003
1004static int btree_releasepage(struct page *page, gfp_t gfp_flags)
1005{
1006	if (PageWriteback(page) || PageDirty(page))
1007		return 0;
1008
1009	return try_release_extent_buffer(page);
1010}
1011
1012static void btree_invalidatepage(struct page *page, unsigned int offset,
1013				 unsigned int length)
1014{
1015	struct extent_io_tree *tree;
1016	tree = &BTRFS_I(page->mapping->host)->io_tree;
1017	extent_invalidatepage(tree, page, offset);
1018	btree_releasepage(page, GFP_NOFS);
1019	if (PagePrivate(page)) {
1020		btrfs_warn(BTRFS_I(page->mapping->host)->root->fs_info,
1021			   "page private not zero on page %llu",
1022			   (unsigned long long)page_offset(page));
1023		ClearPagePrivate(page);
1024		set_page_private(page, 0);
1025		page_cache_release(page);
1026	}
1027}
1028
1029static int btree_set_page_dirty(struct page *page)
1030{
1031#ifdef DEBUG
1032	struct extent_buffer *eb;
1033
1034	BUG_ON(!PagePrivate(page));
1035	eb = (struct extent_buffer *)page->private;
1036	BUG_ON(!eb);
1037	BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
1038	BUG_ON(!atomic_read(&eb->refs));
1039	btrfs_assert_tree_locked(eb);
1040#endif
1041	return __set_page_dirty_nobuffers(page);
1042}
1043
1044static const struct address_space_operations btree_aops = {
1045	.readpage	= btree_readpage,
1046	.writepages	= btree_writepages,
1047	.releasepage	= btree_releasepage,
1048	.invalidatepage = btree_invalidatepage,
1049#ifdef CONFIG_MIGRATION
1050	.migratepage	= btree_migratepage,
1051#endif
1052	.set_page_dirty = btree_set_page_dirty,
1053};
1054
1055int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
1056			 u64 parent_transid)
1057{
1058	struct extent_buffer *buf = NULL;
1059	struct inode *btree_inode = root->fs_info->btree_inode;
1060	int ret = 0;
1061
1062	buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1063	if (!buf)
1064		return 0;
1065	read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
1066				 buf, 0, WAIT_NONE, btree_get_extent, 0);
1067	free_extent_buffer(buf);
1068	return ret;
1069}
1070
1071int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, u32 blocksize,
1072			 int mirror_num, struct extent_buffer **eb)
1073{
1074	struct extent_buffer *buf = NULL;
1075	struct inode *btree_inode = root->fs_info->btree_inode;
1076	struct extent_io_tree *io_tree = &BTRFS_I(btree_inode)->io_tree;
1077	int ret;
1078
1079	buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1080	if (!buf)
1081		return 0;
1082
1083	set_bit(EXTENT_BUFFER_READAHEAD, &buf->bflags);
1084
1085	ret = read_extent_buffer_pages(io_tree, buf, 0, WAIT_PAGE_LOCK,
1086				       btree_get_extent, mirror_num);
1087	if (ret) {
1088		free_extent_buffer(buf);
1089		return ret;
1090	}
1091
1092	if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) {
1093		free_extent_buffer(buf);
1094		return -EIO;
1095	} else if (extent_buffer_uptodate(buf)) {
1096		*eb = buf;
1097	} else {
1098		free_extent_buffer(buf);
1099	}
1100	return 0;
1101}
1102
1103struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
1104					    u64 bytenr, u32 blocksize)
1105{
1106	return find_extent_buffer(root->fs_info, bytenr);
 
 
 
1107}
1108
1109struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
1110						 u64 bytenr, u32 blocksize)
1111{
1112	return alloc_extent_buffer(root->fs_info, bytenr, blocksize);
1113}
1114
1115
1116int btrfs_write_tree_block(struct extent_buffer *buf)
1117{
1118	return filemap_fdatawrite_range(buf->pages[0]->mapping, buf->start,
1119					buf->start + buf->len - 1);
1120}
1121
1122int btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
1123{
1124	return filemap_fdatawait_range(buf->pages[0]->mapping,
1125				       buf->start, buf->start + buf->len - 1);
1126}
1127
1128struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
1129				      u32 blocksize, u64 parent_transid)
1130{
1131	struct extent_buffer *buf = NULL;
1132	int ret;
1133
1134	buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1135	if (!buf)
1136		return NULL;
1137
1138	ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
 
1139	if (ret) {
1140		free_extent_buffer(buf);
1141		return NULL;
1142	}
1143	return buf;
1144
1145}
1146
1147void clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1148		      struct extent_buffer *buf)
1149{
1150	struct btrfs_fs_info *fs_info = root->fs_info;
1151
1152	if (btrfs_header_generation(buf) ==
1153	    fs_info->running_transaction->transid) {
1154		btrfs_assert_tree_locked(buf);
1155
1156		if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
1157			__percpu_counter_add(&fs_info->dirty_metadata_bytes,
1158					     -buf->len,
1159					     fs_info->dirty_metadata_batch);
1160			/* ugh, clear_extent_buffer_dirty needs to lock the page */
1161			btrfs_set_lock_blocking(buf);
1162			clear_extent_buffer_dirty(buf);
1163		}
1164	}
1165}
1166
1167static struct btrfs_subvolume_writers *btrfs_alloc_subvolume_writers(void)
1168{
1169	struct btrfs_subvolume_writers *writers;
1170	int ret;
1171
1172	writers = kmalloc(sizeof(*writers), GFP_NOFS);
1173	if (!writers)
1174		return ERR_PTR(-ENOMEM);
1175
1176	ret = percpu_counter_init(&writers->counter, 0);
1177	if (ret < 0) {
1178		kfree(writers);
1179		return ERR_PTR(ret);
1180	}
1181
1182	init_waitqueue_head(&writers->wait);
1183	return writers;
1184}
1185
1186static void
1187btrfs_free_subvolume_writers(struct btrfs_subvolume_writers *writers)
1188{
1189	percpu_counter_destroy(&writers->counter);
1190	kfree(writers);
1191}
1192
1193static void __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
1194			 u32 stripesize, struct btrfs_root *root,
1195			 struct btrfs_fs_info *fs_info,
1196			 u64 objectid)
1197{
 
1198	root->node = NULL;
1199	root->commit_root = NULL;
1200	root->sectorsize = sectorsize;
1201	root->nodesize = nodesize;
1202	root->leafsize = leafsize;
1203	root->stripesize = stripesize;
1204	root->ref_cows = 0;
1205	root->track_dirty = 0;
1206	root->in_radix = 0;
1207	root->orphan_item_inserted = 0;
1208	root->orphan_cleanup_state = 0;
1209
1210	root->objectid = objectid;
1211	root->last_trans = 0;
1212	root->highest_objectid = 0;
1213	root->nr_delalloc_inodes = 0;
1214	root->nr_ordered_extents = 0;
1215	root->name = NULL;
1216	root->inode_tree = RB_ROOT;
1217	INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
1218	root->block_rsv = NULL;
1219	root->orphan_block_rsv = NULL;
1220
1221	INIT_LIST_HEAD(&root->dirty_list);
1222	INIT_LIST_HEAD(&root->root_list);
1223	INIT_LIST_HEAD(&root->delalloc_inodes);
1224	INIT_LIST_HEAD(&root->delalloc_root);
1225	INIT_LIST_HEAD(&root->ordered_extents);
1226	INIT_LIST_HEAD(&root->ordered_root);
 
1227	INIT_LIST_HEAD(&root->logged_list[0]);
1228	INIT_LIST_HEAD(&root->logged_list[1]);
1229	spin_lock_init(&root->orphan_lock);
1230	spin_lock_init(&root->inode_lock);
1231	spin_lock_init(&root->delalloc_lock);
1232	spin_lock_init(&root->ordered_extent_lock);
1233	spin_lock_init(&root->accounting_lock);
1234	spin_lock_init(&root->log_extents_lock[0]);
1235	spin_lock_init(&root->log_extents_lock[1]);
 
1236	mutex_init(&root->objectid_mutex);
1237	mutex_init(&root->log_mutex);
1238	mutex_init(&root->ordered_extent_mutex);
1239	mutex_init(&root->delalloc_mutex);
1240	init_waitqueue_head(&root->log_writer_wait);
1241	init_waitqueue_head(&root->log_commit_wait[0]);
1242	init_waitqueue_head(&root->log_commit_wait[1]);
1243	INIT_LIST_HEAD(&root->log_ctxs[0]);
1244	INIT_LIST_HEAD(&root->log_ctxs[1]);
1245	atomic_set(&root->log_commit[0], 0);
1246	atomic_set(&root->log_commit[1], 0);
1247	atomic_set(&root->log_writers, 0);
1248	atomic_set(&root->log_batch, 0);
1249	atomic_set(&root->orphan_inodes, 0);
1250	atomic_set(&root->refs, 1);
1251	atomic_set(&root->will_be_snapshoted, 0);
 
1252	root->log_transid = 0;
1253	root->log_transid_committed = -1;
1254	root->last_log_commit = 0;
1255	if (fs_info)
1256		extent_io_tree_init(&root->dirty_log_pages,
1257				     fs_info->btree_inode->i_mapping);
1258
1259	memset(&root->root_key, 0, sizeof(root->root_key));
1260	memset(&root->root_item, 0, sizeof(root->root_item));
1261	memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
1262	memset(&root->root_kobj, 0, sizeof(root->root_kobj));
1263	if (fs_info)
1264		root->defrag_trans_start = fs_info->generation;
1265	else
1266		root->defrag_trans_start = 0;
1267	init_completion(&root->kobj_unregister);
1268	root->defrag_running = 0;
1269	root->root_key.objectid = objectid;
1270	root->anon_dev = 0;
1271
1272	spin_lock_init(&root->root_item_lock);
 
1273}
1274
1275static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info)
 
1276{
1277	struct btrfs_root *root = kzalloc(sizeof(*root), GFP_NOFS);
1278	if (root)
1279		root->fs_info = fs_info;
1280	return root;
1281}
1282
1283#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
1284/* Should only be used by the testing infrastructure */
1285struct btrfs_root *btrfs_alloc_dummy_root(void)
1286{
1287	struct btrfs_root *root;
1288
1289	root = btrfs_alloc_root(NULL);
 
 
 
1290	if (!root)
1291		return ERR_PTR(-ENOMEM);
1292	__setup_root(4096, 4096, 4096, 4096, root, NULL, 1);
1293	root->dummy_root = 1;
 
 
1294
1295	return root;
1296}
1297#endif
1298
1299struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
1300				     struct btrfs_fs_info *fs_info,
1301				     u64 objectid)
1302{
 
1303	struct extent_buffer *leaf;
1304	struct btrfs_root *tree_root = fs_info->tree_root;
1305	struct btrfs_root *root;
1306	struct btrfs_key key;
 
1307	int ret = 0;
1308	uuid_le uuid;
1309
1310	root = btrfs_alloc_root(fs_info);
 
 
 
 
 
 
1311	if (!root)
1312		return ERR_PTR(-ENOMEM);
1313
1314	__setup_root(tree_root->nodesize, tree_root->leafsize,
1315		     tree_root->sectorsize, tree_root->stripesize,
1316		     root, fs_info, objectid);
1317	root->root_key.objectid = objectid;
1318	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1319	root->root_key.offset = 0;
1320
1321	leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
1322				      0, objectid, NULL, 0, 0, 0);
1323	if (IS_ERR(leaf)) {
1324		ret = PTR_ERR(leaf);
1325		leaf = NULL;
1326		goto fail;
1327	}
1328
1329	memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
1330	btrfs_set_header_bytenr(leaf, leaf->start);
1331	btrfs_set_header_generation(leaf, trans->transid);
1332	btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
1333	btrfs_set_header_owner(leaf, objectid);
1334	root->node = leaf;
1335
1336	write_extent_buffer(leaf, fs_info->fsid, btrfs_header_fsid(),
1337			    BTRFS_FSID_SIZE);
1338	write_extent_buffer(leaf, fs_info->chunk_tree_uuid,
1339			    btrfs_header_chunk_tree_uuid(leaf),
1340			    BTRFS_UUID_SIZE);
1341	btrfs_mark_buffer_dirty(leaf);
1342
1343	root->commit_root = btrfs_root_node(root);
1344	root->track_dirty = 1;
1345
1346
1347	root->root_item.flags = 0;
1348	root->root_item.byte_limit = 0;
1349	btrfs_set_root_bytenr(&root->root_item, leaf->start);
1350	btrfs_set_root_generation(&root->root_item, trans->transid);
1351	btrfs_set_root_level(&root->root_item, 0);
1352	btrfs_set_root_refs(&root->root_item, 1);
1353	btrfs_set_root_used(&root->root_item, leaf->len);
1354	btrfs_set_root_last_snapshot(&root->root_item, 0);
1355	btrfs_set_root_dirid(&root->root_item, 0);
1356	uuid_le_gen(&uuid);
 
1357	memcpy(root->root_item.uuid, uuid.b, BTRFS_UUID_SIZE);
1358	root->root_item.drop_level = 0;
1359
1360	key.objectid = objectid;
1361	key.type = BTRFS_ROOT_ITEM_KEY;
1362	key.offset = 0;
1363	ret = btrfs_insert_root(trans, tree_root, &key, &root->root_item);
1364	if (ret)
1365		goto fail;
1366
1367	btrfs_tree_unlock(leaf);
1368
1369	return root;
1370
1371fail:
1372	if (leaf) {
1373		btrfs_tree_unlock(leaf);
 
1374		free_extent_buffer(leaf);
1375	}
1376	kfree(root);
1377
1378	return ERR_PTR(ret);
1379}
1380
1381static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
1382					 struct btrfs_fs_info *fs_info)
1383{
1384	struct btrfs_root *root;
1385	struct btrfs_root *tree_root = fs_info->tree_root;
1386	struct extent_buffer *leaf;
1387
1388	root = btrfs_alloc_root(fs_info);
1389	if (!root)
1390		return ERR_PTR(-ENOMEM);
1391
1392	__setup_root(tree_root->nodesize, tree_root->leafsize,
1393		     tree_root->sectorsize, tree_root->stripesize,
1394		     root, fs_info, BTRFS_TREE_LOG_OBJECTID);
1395
1396	root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1397	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1398	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
 
1399	/*
 
 
1400	 * log trees do not get reference counted because they go away
1401	 * before a real commit is actually done.  They do store pointers
1402	 * to file data extents, and those reference counts still get
1403	 * updated (along with back refs to the log tree).
1404	 */
1405	root->ref_cows = 0;
1406
1407	leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
1408				      BTRFS_TREE_LOG_OBJECTID, NULL,
1409				      0, 0, 0);
1410	if (IS_ERR(leaf)) {
1411		kfree(root);
1412		return ERR_CAST(leaf);
1413	}
1414
1415	memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
1416	btrfs_set_header_bytenr(leaf, leaf->start);
1417	btrfs_set_header_generation(leaf, trans->transid);
1418	btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
1419	btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
1420	root->node = leaf;
1421
1422	write_extent_buffer(root->node, root->fs_info->fsid,
1423			    btrfs_header_fsid(), BTRFS_FSID_SIZE);
1424	btrfs_mark_buffer_dirty(root->node);
1425	btrfs_tree_unlock(root->node);
1426	return root;
1427}
1428
1429int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1430			     struct btrfs_fs_info *fs_info)
1431{
1432	struct btrfs_root *log_root;
1433
1434	log_root = alloc_log_tree(trans, fs_info);
1435	if (IS_ERR(log_root))
1436		return PTR_ERR(log_root);
1437	WARN_ON(fs_info->log_root_tree);
1438	fs_info->log_root_tree = log_root;
1439	return 0;
1440}
1441
1442int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1443		       struct btrfs_root *root)
1444{
 
1445	struct btrfs_root *log_root;
1446	struct btrfs_inode_item *inode_item;
1447
1448	log_root = alloc_log_tree(trans, root->fs_info);
1449	if (IS_ERR(log_root))
1450		return PTR_ERR(log_root);
1451
1452	log_root->last_trans = trans->transid;
1453	log_root->root_key.offset = root->root_key.objectid;
1454
1455	inode_item = &log_root->root_item.inode;
1456	btrfs_set_stack_inode_generation(inode_item, 1);
1457	btrfs_set_stack_inode_size(inode_item, 3);
1458	btrfs_set_stack_inode_nlink(inode_item, 1);
1459	btrfs_set_stack_inode_nbytes(inode_item, root->leafsize);
 
1460	btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
1461
1462	btrfs_set_root_node(&log_root->root_item, log_root->node);
1463
1464	WARN_ON(root->log_root);
1465	root->log_root = log_root;
1466	root->log_transid = 0;
1467	root->log_transid_committed = -1;
1468	root->last_log_commit = 0;
1469	return 0;
1470}
1471
1472static struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
1473					       struct btrfs_key *key)
1474{
1475	struct btrfs_root *root;
1476	struct btrfs_fs_info *fs_info = tree_root->fs_info;
1477	struct btrfs_path *path;
1478	u64 generation;
1479	u32 blocksize;
1480	int ret;
 
1481
1482	path = btrfs_alloc_path();
1483	if (!path)
1484		return ERR_PTR(-ENOMEM);
1485
1486	root = btrfs_alloc_root(fs_info);
1487	if (!root) {
1488		ret = -ENOMEM;
1489		goto alloc_fail;
1490	}
1491
1492	__setup_root(tree_root->nodesize, tree_root->leafsize,
1493		     tree_root->sectorsize, tree_root->stripesize,
1494		     root, fs_info, key->objectid);
1495
1496	ret = btrfs_find_root(tree_root, key, path,
1497			      &root->root_item, &root->root_key);
1498	if (ret) {
1499		if (ret > 0)
1500			ret = -ENOENT;
1501		goto find_fail;
1502	}
1503
1504	generation = btrfs_root_generation(&root->root_item);
1505	blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
1506	root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
1507				     blocksize, generation);
1508	if (!root->node) {
1509		ret = -ENOMEM;
 
1510		goto find_fail;
1511	} else if (!btrfs_buffer_uptodate(root->node, generation, 0)) {
1512		ret = -EIO;
1513		goto read_fail;
 
1514	}
1515	root->commit_root = btrfs_root_node(root);
1516out:
1517	btrfs_free_path(path);
1518	return root;
1519
1520read_fail:
1521	free_extent_buffer(root->node);
1522find_fail:
1523	kfree(root);
1524alloc_fail:
1525	root = ERR_PTR(ret);
1526	goto out;
1527}
1528
1529struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root,
1530				      struct btrfs_key *location)
1531{
1532	struct btrfs_root *root;
1533
1534	root = btrfs_read_tree_root(tree_root, location);
1535	if (IS_ERR(root))
1536		return root;
1537
1538	if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
1539		root->ref_cows = 1;
1540		btrfs_check_and_init_root_item(&root->root_item);
1541	}
1542
1543	return root;
1544}
1545
1546int btrfs_init_fs_root(struct btrfs_root *root)
1547{
1548	int ret;
1549	struct btrfs_subvolume_writers *writers;
1550
1551	root->free_ino_ctl = kzalloc(sizeof(*root->free_ino_ctl), GFP_NOFS);
1552	root->free_ino_pinned = kzalloc(sizeof(*root->free_ino_pinned),
1553					GFP_NOFS);
1554	if (!root->free_ino_pinned || !root->free_ino_ctl) {
1555		ret = -ENOMEM;
1556		goto fail;
1557	}
1558
1559	writers = btrfs_alloc_subvolume_writers();
1560	if (IS_ERR(writers)) {
1561		ret = PTR_ERR(writers);
1562		goto fail;
1563	}
1564	root->subv_writers = writers;
1565
1566	btrfs_init_free_ino_ctl(root);
1567	spin_lock_init(&root->cache_lock);
1568	init_waitqueue_head(&root->cache_wait);
1569
1570	ret = get_anon_bdev(&root->anon_dev);
1571	if (ret)
1572		goto free_writers;
 
 
 
 
 
 
 
 
 
 
 
 
 
1573	return 0;
1574
1575free_writers:
1576	btrfs_free_subvolume_writers(root->subv_writers);
1577fail:
1578	kfree(root->free_ino_ctl);
1579	kfree(root->free_ino_pinned);
1580	return ret;
1581}
1582
1583static struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
1584					       u64 root_id)
1585{
1586	struct btrfs_root *root;
1587
1588	spin_lock(&fs_info->fs_roots_radix_lock);
1589	root = radix_tree_lookup(&fs_info->fs_roots_radix,
1590				 (unsigned long)root_id);
1591	spin_unlock(&fs_info->fs_roots_radix_lock);
1592	return root;
1593}
1594
1595int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
1596			 struct btrfs_root *root)
1597{
1598	int ret;
1599
1600	ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
1601	if (ret)
1602		return ret;
1603
1604	spin_lock(&fs_info->fs_roots_radix_lock);
1605	ret = radix_tree_insert(&fs_info->fs_roots_radix,
1606				(unsigned long)root->root_key.objectid,
1607				root);
1608	if (ret == 0)
1609		root->in_radix = 1;
1610	spin_unlock(&fs_info->fs_roots_radix_lock);
1611	radix_tree_preload_end();
1612
1613	return ret;
1614}
1615
1616struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
1617				     struct btrfs_key *location,
1618				     bool check_ref)
1619{
1620	struct btrfs_root *root;
 
 
1621	int ret;
1622
1623	if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1624		return fs_info->tree_root;
1625	if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
1626		return fs_info->extent_root;
1627	if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
1628		return fs_info->chunk_root;
1629	if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
1630		return fs_info->dev_root;
1631	if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
1632		return fs_info->csum_root;
1633	if (location->objectid == BTRFS_QUOTA_TREE_OBJECTID)
1634		return fs_info->quota_root ? fs_info->quota_root :
1635					     ERR_PTR(-ENOENT);
1636	if (location->objectid == BTRFS_UUID_TREE_OBJECTID)
1637		return fs_info->uuid_root ? fs_info->uuid_root :
1638					    ERR_PTR(-ENOENT);
 
 
 
1639again:
1640	root = btrfs_lookup_fs_root(fs_info, location->objectid);
1641	if (root) {
1642		if (check_ref && btrfs_root_refs(&root->root_item) == 0)
1643			return ERR_PTR(-ENOENT);
1644		return root;
1645	}
1646
1647	root = btrfs_read_fs_root(fs_info->tree_root, location);
1648	if (IS_ERR(root))
1649		return root;
1650
1651	if (check_ref && btrfs_root_refs(&root->root_item) == 0) {
1652		ret = -ENOENT;
1653		goto fail;
1654	}
1655
1656	ret = btrfs_init_fs_root(root);
1657	if (ret)
1658		goto fail;
1659
1660	ret = btrfs_find_item(fs_info->tree_root, NULL, BTRFS_ORPHAN_OBJECTID,
1661			location->objectid, BTRFS_ORPHAN_ITEM_KEY, NULL);
 
 
 
 
 
 
 
 
 
1662	if (ret < 0)
1663		goto fail;
1664	if (ret == 0)
1665		root->orphan_item_inserted = 1;
1666
1667	ret = btrfs_insert_fs_root(fs_info, root);
1668	if (ret) {
1669		if (ret == -EEXIST) {
1670			free_fs_root(root);
1671			goto again;
1672		}
1673		goto fail;
1674	}
1675	return root;
1676fail:
1677	free_fs_root(root);
1678	return ERR_PTR(ret);
1679}
1680
1681static int btrfs_congested_fn(void *congested_data, int bdi_bits)
1682{
1683	struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
1684	int ret = 0;
1685	struct btrfs_device *device;
1686	struct backing_dev_info *bdi;
1687
1688	rcu_read_lock();
1689	list_for_each_entry_rcu(device, &info->fs_devices->devices, dev_list) {
1690		if (!device->bdev)
1691			continue;
1692		bdi = blk_get_backing_dev_info(device->bdev);
1693		if (bdi && bdi_congested(bdi, bdi_bits)) {
1694			ret = 1;
1695			break;
1696		}
1697	}
1698	rcu_read_unlock();
1699	return ret;
1700}
1701
1702/*
1703 * If this fails, caller must call bdi_destroy() to get rid of the
1704 * bdi again.
1705 */
1706static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
1707{
1708	int err;
1709
1710	bdi->capabilities = BDI_CAP_MAP_COPY;
1711	err = bdi_setup_and_register(bdi, "btrfs", BDI_CAP_MAP_COPY);
1712	if (err)
1713		return err;
1714
1715	bdi->ra_pages	= default_backing_dev_info.ra_pages;
1716	bdi->congested_fn	= btrfs_congested_fn;
1717	bdi->congested_data	= info;
1718	return 0;
1719}
1720
1721/*
1722 * called by the kthread helper functions to finally call the bio end_io
1723 * functions.  This is where read checksum verification actually happens
1724 */
1725static void end_workqueue_fn(struct btrfs_work *work)
1726{
1727	struct bio *bio;
1728	struct end_io_wq *end_io_wq;
1729	int error;
1730
1731	end_io_wq = container_of(work, struct end_io_wq, work);
1732	bio = end_io_wq->bio;
1733
1734	error = end_io_wq->error;
1735	bio->bi_private = end_io_wq->private;
1736	bio->bi_end_io = end_io_wq->end_io;
1737	kfree(end_io_wq);
1738	bio_endio_nodec(bio, error);
1739}
1740
1741static int cleaner_kthread(void *arg)
1742{
1743	struct btrfs_root *root = arg;
 
1744	int again;
1745
1746	do {
1747		again = 0;
1748
 
 
1749		/* Make the cleaner go to sleep early. */
1750		if (btrfs_need_cleaner_sleep(root))
 
 
 
 
 
 
 
1751			goto sleep;
1752
1753		if (!mutex_trylock(&root->fs_info->cleaner_mutex))
1754			goto sleep;
1755
1756		/*
1757		 * Avoid the problem that we change the status of the fs
1758		 * during the above check and trylock.
1759		 */
1760		if (btrfs_need_cleaner_sleep(root)) {
1761			mutex_unlock(&root->fs_info->cleaner_mutex);
1762			goto sleep;
1763		}
1764
1765		btrfs_run_delayed_iputs(root);
 
1766		again = btrfs_clean_one_deleted_snapshot(root);
1767		mutex_unlock(&root->fs_info->cleaner_mutex);
1768
1769		/*
1770		 * The defragger has dealt with the R/O remount and umount,
1771		 * needn't do anything special here.
1772		 */
1773		btrfs_run_defrag_inodes(root->fs_info);
 
 
 
 
 
 
 
 
 
 
1774sleep:
1775		if (!try_to_freeze() && !again) {
 
 
 
 
 
1776			set_current_state(TASK_INTERRUPTIBLE);
1777			if (!kthread_should_stop())
1778				schedule();
1779			__set_current_state(TASK_RUNNING);
1780		}
1781	} while (!kthread_should_stop());
1782	return 0;
1783}
1784
1785static int transaction_kthread(void *arg)
1786{
1787	struct btrfs_root *root = arg;
 
1788	struct btrfs_trans_handle *trans;
1789	struct btrfs_transaction *cur;
1790	u64 transid;
1791	unsigned long now;
1792	unsigned long delay;
1793	bool cannot_commit;
1794
1795	do {
1796		cannot_commit = false;
1797		delay = HZ * root->fs_info->commit_interval;
1798		mutex_lock(&root->fs_info->transaction_kthread_mutex);
1799
1800		spin_lock(&root->fs_info->trans_lock);
1801		cur = root->fs_info->running_transaction;
1802		if (!cur) {
1803			spin_unlock(&root->fs_info->trans_lock);
1804			goto sleep;
1805		}
1806
1807		now = get_seconds();
1808		if (cur->state < TRANS_STATE_BLOCKED &&
 
1809		    (now < cur->start_time ||
1810		     now - cur->start_time < root->fs_info->commit_interval)) {
1811			spin_unlock(&root->fs_info->trans_lock);
1812			delay = HZ * 5;
1813			goto sleep;
1814		}
1815		transid = cur->transid;
1816		spin_unlock(&root->fs_info->trans_lock);
1817
1818		/* If the file system is aborted, this will always fail. */
1819		trans = btrfs_attach_transaction(root);
1820		if (IS_ERR(trans)) {
1821			if (PTR_ERR(trans) != -ENOENT)
1822				cannot_commit = true;
1823			goto sleep;
1824		}
1825		if (transid == trans->transid) {
1826			btrfs_commit_transaction(trans, root);
1827		} else {
1828			btrfs_end_transaction(trans, root);
1829		}
1830sleep:
1831		wake_up_process(root->fs_info->cleaner_kthread);
1832		mutex_unlock(&root->fs_info->transaction_kthread_mutex);
1833
1834		if (unlikely(test_bit(BTRFS_FS_STATE_ERROR,
1835				      &root->fs_info->fs_state)))
1836			btrfs_cleanup_transaction(root);
1837		if (!try_to_freeze()) {
1838			set_current_state(TASK_INTERRUPTIBLE);
1839			if (!kthread_should_stop() &&
1840			    (!btrfs_transaction_blocked(root->fs_info) ||
1841			     cannot_commit))
1842				schedule_timeout(delay);
1843			__set_current_state(TASK_RUNNING);
1844		}
1845	} while (!kthread_should_stop());
1846	return 0;
1847}
1848
1849/*
1850 * this will find the highest generation in the array of
1851 * root backups.  The index of the highest array is returned,
1852 * or -1 if we can't find anything.
1853 *
1854 * We check to make sure the array is valid by comparing the
1855 * generation of the latest  root in the array with the generation
1856 * in the super block.  If they don't match we pitch it.
1857 */
1858static int find_newest_super_backup(struct btrfs_fs_info *info, u64 newest_gen)
1859{
1860	u64 cur;
1861	int newest_index = -1;
1862	struct btrfs_root_backup *root_backup;
1863	int i;
1864
1865	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
1866		root_backup = info->super_copy->super_roots + i;
1867		cur = btrfs_backup_tree_root_gen(root_backup);
1868		if (cur == newest_gen)
1869			newest_index = i;
1870	}
1871
1872	/* check to see if we actually wrapped around */
1873	if (newest_index == BTRFS_NUM_BACKUP_ROOTS - 1) {
1874		root_backup = info->super_copy->super_roots;
1875		cur = btrfs_backup_tree_root_gen(root_backup);
1876		if (cur == newest_gen)
1877			newest_index = 0;
1878	}
1879	return newest_index;
1880}
1881
1882
1883/*
1884 * find the oldest backup so we know where to store new entries
1885 * in the backup array.  This will set the backup_root_index
1886 * field in the fs_info struct
1887 */
1888static void find_oldest_super_backup(struct btrfs_fs_info *info,
1889				     u64 newest_gen)
1890{
1891	int newest_index = -1;
1892
1893	newest_index = find_newest_super_backup(info, newest_gen);
1894	/* if there was garbage in there, just move along */
1895	if (newest_index == -1) {
1896		info->backup_root_index = 0;
1897	} else {
1898		info->backup_root_index = (newest_index + 1) % BTRFS_NUM_BACKUP_ROOTS;
1899	}
1900}
1901
1902/*
1903 * copy all the root pointers into the super backup array.
1904 * this will bump the backup pointer by one when it is
1905 * done
1906 */
1907static void backup_super_roots(struct btrfs_fs_info *info)
1908{
1909	int next_backup;
1910	struct btrfs_root_backup *root_backup;
1911	int last_backup;
1912
1913	next_backup = info->backup_root_index;
1914	last_backup = (next_backup + BTRFS_NUM_BACKUP_ROOTS - 1) %
1915		BTRFS_NUM_BACKUP_ROOTS;
1916
1917	/*
1918	 * just overwrite the last backup if we're at the same generation
1919	 * this happens only at umount
1920	 */
1921	root_backup = info->super_for_commit->super_roots + last_backup;
1922	if (btrfs_backup_tree_root_gen(root_backup) ==
1923	    btrfs_header_generation(info->tree_root->node))
1924		next_backup = last_backup;
1925
1926	root_backup = info->super_for_commit->super_roots + next_backup;
1927
1928	/*
1929	 * make sure all of our padding and empty slots get zero filled
1930	 * regardless of which ones we use today
1931	 */
1932	memset(root_backup, 0, sizeof(*root_backup));
1933
1934	info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
1935
1936	btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
1937	btrfs_set_backup_tree_root_gen(root_backup,
1938			       btrfs_header_generation(info->tree_root->node));
1939
1940	btrfs_set_backup_tree_root_level(root_backup,
1941			       btrfs_header_level(info->tree_root->node));
1942
1943	btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
1944	btrfs_set_backup_chunk_root_gen(root_backup,
1945			       btrfs_header_generation(info->chunk_root->node));
1946	btrfs_set_backup_chunk_root_level(root_backup,
1947			       btrfs_header_level(info->chunk_root->node));
1948
1949	btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start);
1950	btrfs_set_backup_extent_root_gen(root_backup,
1951			       btrfs_header_generation(info->extent_root->node));
1952	btrfs_set_backup_extent_root_level(root_backup,
1953			       btrfs_header_level(info->extent_root->node));
1954
1955	/*
1956	 * we might commit during log recovery, which happens before we set
1957	 * the fs_root.  Make sure it is valid before we fill it in.
1958	 */
1959	if (info->fs_root && info->fs_root->node) {
1960		btrfs_set_backup_fs_root(root_backup,
1961					 info->fs_root->node->start);
1962		btrfs_set_backup_fs_root_gen(root_backup,
1963			       btrfs_header_generation(info->fs_root->node));
1964		btrfs_set_backup_fs_root_level(root_backup,
1965			       btrfs_header_level(info->fs_root->node));
1966	}
1967
1968	btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
1969	btrfs_set_backup_dev_root_gen(root_backup,
1970			       btrfs_header_generation(info->dev_root->node));
1971	btrfs_set_backup_dev_root_level(root_backup,
1972				       btrfs_header_level(info->dev_root->node));
1973
1974	btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start);
1975	btrfs_set_backup_csum_root_gen(root_backup,
1976			       btrfs_header_generation(info->csum_root->node));
1977	btrfs_set_backup_csum_root_level(root_backup,
1978			       btrfs_header_level(info->csum_root->node));
1979
1980	btrfs_set_backup_total_bytes(root_backup,
1981			     btrfs_super_total_bytes(info->super_copy));
1982	btrfs_set_backup_bytes_used(root_backup,
1983			     btrfs_super_bytes_used(info->super_copy));
1984	btrfs_set_backup_num_devices(root_backup,
1985			     btrfs_super_num_devices(info->super_copy));
1986
1987	/*
1988	 * if we don't copy this out to the super_copy, it won't get remembered
1989	 * for the next commit
1990	 */
1991	memcpy(&info->super_copy->super_roots,
1992	       &info->super_for_commit->super_roots,
1993	       sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
1994}
1995
1996/*
1997 * this copies info out of the root backup array and back into
1998 * the in-memory super block.  It is meant to help iterate through
1999 * the array, so you send it the number of backups you've already
2000 * tried and the last backup index you used.
2001 *
2002 * this returns -1 when it has tried all the backups
2003 */
2004static noinline int next_root_backup(struct btrfs_fs_info *info,
2005				     struct btrfs_super_block *super,
2006				     int *num_backups_tried, int *backup_index)
2007{
2008	struct btrfs_root_backup *root_backup;
2009	int newest = *backup_index;
2010
2011	if (*num_backups_tried == 0) {
2012		u64 gen = btrfs_super_generation(super);
2013
2014		newest = find_newest_super_backup(info, gen);
2015		if (newest == -1)
2016			return -1;
2017
2018		*backup_index = newest;
2019		*num_backups_tried = 1;
2020	} else if (*num_backups_tried == BTRFS_NUM_BACKUP_ROOTS) {
2021		/* we've tried all the backups, all done */
2022		return -1;
2023	} else {
2024		/* jump to the next oldest backup */
2025		newest = (*backup_index + BTRFS_NUM_BACKUP_ROOTS - 1) %
2026			BTRFS_NUM_BACKUP_ROOTS;
2027		*backup_index = newest;
2028		*num_backups_tried += 1;
2029	}
2030	root_backup = super->super_roots + newest;
2031
2032	btrfs_set_super_generation(super,
2033				   btrfs_backup_tree_root_gen(root_backup));
2034	btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
2035	btrfs_set_super_root_level(super,
2036				   btrfs_backup_tree_root_level(root_backup));
2037	btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
2038
2039	/*
2040	 * fixme: the total bytes and num_devices need to match or we should
2041	 * need a fsck
2042	 */
2043	btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
2044	btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
2045	return 0;
2046}
2047
2048/* helper to cleanup workers */
2049static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
2050{
2051	btrfs_destroy_workqueue(fs_info->fixup_workers);
2052	btrfs_destroy_workqueue(fs_info->delalloc_workers);
2053	btrfs_destroy_workqueue(fs_info->workers);
2054	btrfs_destroy_workqueue(fs_info->endio_workers);
2055	btrfs_destroy_workqueue(fs_info->endio_meta_workers);
2056	btrfs_destroy_workqueue(fs_info->endio_raid56_workers);
 
2057	btrfs_destroy_workqueue(fs_info->rmw_workers);
2058	btrfs_destroy_workqueue(fs_info->endio_meta_write_workers);
2059	btrfs_destroy_workqueue(fs_info->endio_write_workers);
2060	btrfs_destroy_workqueue(fs_info->endio_freespace_worker);
2061	btrfs_destroy_workqueue(fs_info->submit_workers);
2062	btrfs_destroy_workqueue(fs_info->delayed_workers);
2063	btrfs_destroy_workqueue(fs_info->caching_workers);
2064	btrfs_destroy_workqueue(fs_info->readahead_workers);
2065	btrfs_destroy_workqueue(fs_info->flush_workers);
2066	btrfs_destroy_workqueue(fs_info->qgroup_rescan_workers);
 
 
 
 
 
 
 
2067}
2068
2069static void free_root_extent_buffers(struct btrfs_root *root)
2070{
2071	if (root) {
2072		free_extent_buffer(root->node);
2073		free_extent_buffer(root->commit_root);
2074		root->node = NULL;
2075		root->commit_root = NULL;
2076	}
2077}
2078
2079/* helper to cleanup tree roots */
2080static void free_root_pointers(struct btrfs_fs_info *info, int chunk_root)
2081{
2082	free_root_extent_buffers(info->tree_root);
2083
2084	free_root_extent_buffers(info->dev_root);
2085	free_root_extent_buffers(info->extent_root);
2086	free_root_extent_buffers(info->csum_root);
2087	free_root_extent_buffers(info->quota_root);
2088	free_root_extent_buffers(info->uuid_root);
2089	if (chunk_root)
2090		free_root_extent_buffers(info->chunk_root);
 
2091}
2092
2093static void del_fs_roots(struct btrfs_fs_info *fs_info)
2094{
2095	int ret;
2096	struct btrfs_root *gang[8];
2097	int i;
2098
2099	while (!list_empty(&fs_info->dead_roots)) {
2100		gang[0] = list_entry(fs_info->dead_roots.next,
2101				     struct btrfs_root, root_list);
2102		list_del(&gang[0]->root_list);
2103
2104		if (gang[0]->in_radix) {
2105			btrfs_drop_and_free_fs_root(fs_info, gang[0]);
2106		} else {
2107			free_extent_buffer(gang[0]->node);
2108			free_extent_buffer(gang[0]->commit_root);
2109			btrfs_put_fs_root(gang[0]);
2110		}
2111	}
2112
2113	while (1) {
2114		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2115					     (void **)gang, 0,
2116					     ARRAY_SIZE(gang));
2117		if (!ret)
2118			break;
2119		for (i = 0; i < ret; i++)
2120			btrfs_drop_and_free_fs_root(fs_info, gang[i]);
2121	}
2122
2123	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
2124		btrfs_free_log_root_tree(NULL, fs_info);
2125		btrfs_destroy_pinned_extent(fs_info->tree_root,
2126					    fs_info->pinned_extents);
2127	}
2128}
2129
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2130int open_ctree(struct super_block *sb,
2131	       struct btrfs_fs_devices *fs_devices,
2132	       char *options)
2133{
2134	u32 sectorsize;
2135	u32 nodesize;
2136	u32 leafsize;
2137	u32 blocksize;
2138	u32 stripesize;
2139	u64 generation;
2140	u64 features;
 
2141	struct btrfs_key location;
2142	struct buffer_head *bh;
2143	struct btrfs_super_block *disk_super;
2144	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
2145	struct btrfs_root *tree_root;
2146	struct btrfs_root *extent_root;
2147	struct btrfs_root *csum_root;
2148	struct btrfs_root *chunk_root;
2149	struct btrfs_root *dev_root;
2150	struct btrfs_root *quota_root;
2151	struct btrfs_root *uuid_root;
2152	struct btrfs_root *log_tree_root;
2153	int ret;
2154	int err = -EINVAL;
2155	int num_backups_tried = 0;
2156	int backup_index = 0;
2157	int max_active;
2158	int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND;
2159	bool create_uuid_tree;
2160	bool check_uuid_tree;
2161
2162	tree_root = fs_info->tree_root = btrfs_alloc_root(fs_info);
2163	chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info);
2164	if (!tree_root || !chunk_root) {
2165		err = -ENOMEM;
2166		goto fail;
2167	}
2168
2169	ret = init_srcu_struct(&fs_info->subvol_srcu);
2170	if (ret) {
2171		err = ret;
2172		goto fail;
2173	}
2174
2175	ret = setup_bdi(fs_info, &fs_info->bdi);
2176	if (ret) {
2177		err = ret;
2178		goto fail_srcu;
2179	}
2180
2181	ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0);
2182	if (ret) {
2183		err = ret;
2184		goto fail_bdi;
2185	}
2186	fs_info->dirty_metadata_batch = PAGE_CACHE_SIZE *
2187					(1 + ilog2(nr_cpu_ids));
2188
2189	ret = percpu_counter_init(&fs_info->delalloc_bytes, 0);
2190	if (ret) {
2191		err = ret;
2192		goto fail_dirty_metadata_bytes;
2193	}
2194
2195	ret = percpu_counter_init(&fs_info->bio_counter, 0);
 
2196	if (ret) {
2197		err = ret;
2198		goto fail_delalloc_bytes;
2199	}
2200
2201	fs_info->btree_inode = new_inode(sb);
2202	if (!fs_info->btree_inode) {
2203		err = -ENOMEM;
2204		goto fail_bio_counter;
2205	}
2206
2207	mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
2208
2209	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
2210	INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC);
2211	INIT_LIST_HEAD(&fs_info->trans_list);
2212	INIT_LIST_HEAD(&fs_info->dead_roots);
2213	INIT_LIST_HEAD(&fs_info->delayed_iputs);
2214	INIT_LIST_HEAD(&fs_info->delalloc_roots);
2215	INIT_LIST_HEAD(&fs_info->caching_block_groups);
2216	spin_lock_init(&fs_info->delalloc_root_lock);
2217	spin_lock_init(&fs_info->trans_lock);
2218	spin_lock_init(&fs_info->fs_roots_radix_lock);
2219	spin_lock_init(&fs_info->delayed_iput_lock);
2220	spin_lock_init(&fs_info->defrag_inodes_lock);
2221	spin_lock_init(&fs_info->free_chunk_lock);
2222	spin_lock_init(&fs_info->tree_mod_seq_lock);
2223	spin_lock_init(&fs_info->super_lock);
2224	spin_lock_init(&fs_info->buffer_lock);
 
2225	rwlock_init(&fs_info->tree_mod_log_lock);
 
 
2226	mutex_init(&fs_info->reloc_mutex);
2227	mutex_init(&fs_info->delalloc_root_mutex);
2228	seqlock_init(&fs_info->profiles_lock);
2229
2230	init_completion(&fs_info->kobj_unregister);
2231	INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
2232	INIT_LIST_HEAD(&fs_info->space_info);
2233	INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
2234	btrfs_mapping_init(&fs_info->mapping_tree);
 
2235	btrfs_init_block_rsv(&fs_info->global_block_rsv,
2236			     BTRFS_BLOCK_RSV_GLOBAL);
2237	btrfs_init_block_rsv(&fs_info->delalloc_block_rsv,
2238			     BTRFS_BLOCK_RSV_DELALLOC);
2239	btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
2240	btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK);
2241	btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY);
2242	btrfs_init_block_rsv(&fs_info->delayed_block_rsv,
2243			     BTRFS_BLOCK_RSV_DELOPS);
2244	atomic_set(&fs_info->nr_async_submits, 0);
 
 
2245	atomic_set(&fs_info->async_delalloc_pages, 0);
2246	atomic_set(&fs_info->async_submit_draining, 0);
2247	atomic_set(&fs_info->nr_async_bios, 0);
2248	atomic_set(&fs_info->defrag_running, 0);
 
 
2249	atomic64_set(&fs_info->tree_mod_seq, 0);
2250	fs_info->sb = sb;
2251	fs_info->max_inline = 8192 * 1024;
2252	fs_info->metadata_ratio = 0;
2253	fs_info->defrag_inodes = RB_ROOT;
2254	fs_info->free_chunk_space = 0;
2255	fs_info->tree_mod_log = RB_ROOT;
2256	fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
2257	fs_info->avg_delayed_ref_runtime = div64_u64(NSEC_PER_SEC, 64);
2258	/* readahead state */
2259	INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_WAIT);
2260	spin_lock_init(&fs_info->reada_lock);
 
2261
2262	fs_info->thread_pool_size = min_t(unsigned long,
2263					  num_online_cpus() + 2, 8);
2264
2265	INIT_LIST_HEAD(&fs_info->ordered_roots);
2266	spin_lock_init(&fs_info->ordered_root_lock);
 
 
 
 
 
 
 
 
2267	fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
2268					GFP_NOFS);
2269	if (!fs_info->delayed_root) {
2270		err = -ENOMEM;
2271		goto fail_iput;
2272	}
2273	btrfs_init_delayed_root(fs_info->delayed_root);
2274
2275	mutex_init(&fs_info->scrub_lock);
2276	atomic_set(&fs_info->scrubs_running, 0);
2277	atomic_set(&fs_info->scrub_pause_req, 0);
2278	atomic_set(&fs_info->scrubs_paused, 0);
2279	atomic_set(&fs_info->scrub_cancel_req, 0);
2280	init_waitqueue_head(&fs_info->replace_wait);
2281	init_waitqueue_head(&fs_info->scrub_pause_wait);
2282	fs_info->scrub_workers_refcnt = 0;
2283#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
2284	fs_info->check_integrity_print_mask = 0;
2285#endif
 
 
2286
2287	spin_lock_init(&fs_info->balance_lock);
2288	mutex_init(&fs_info->balance_mutex);
2289	atomic_set(&fs_info->balance_running, 0);
2290	atomic_set(&fs_info->balance_pause_req, 0);
2291	atomic_set(&fs_info->balance_cancel_req, 0);
2292	fs_info->balance_ctl = NULL;
2293	init_waitqueue_head(&fs_info->balance_wait_q);
2294
2295	sb->s_blocksize = 4096;
2296	sb->s_blocksize_bits = blksize_bits(4096);
2297	sb->s_bdi = &fs_info->bdi;
2298
2299	fs_info->btree_inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
2300	set_nlink(fs_info->btree_inode, 1);
2301	/*
2302	 * we set the i_size on the btree inode to the max possible int.
2303	 * the real end of the address space is determined by all of
2304	 * the devices in the system
2305	 */
2306	fs_info->btree_inode->i_size = OFFSET_MAX;
2307	fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
2308	fs_info->btree_inode->i_mapping->backing_dev_info = &fs_info->bdi;
2309
2310	RB_CLEAR_NODE(&BTRFS_I(fs_info->btree_inode)->rb_node);
2311	extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree,
2312			     fs_info->btree_inode->i_mapping);
2313	BTRFS_I(fs_info->btree_inode)->io_tree.track_uptodate = 0;
2314	extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree);
2315
2316	BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops;
2317
2318	BTRFS_I(fs_info->btree_inode)->root = tree_root;
2319	memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
2320	       sizeof(struct btrfs_key));
2321	set_bit(BTRFS_INODE_DUMMY,
2322		&BTRFS_I(fs_info->btree_inode)->runtime_flags);
2323	btrfs_insert_inode_hash(fs_info->btree_inode);
2324
2325	spin_lock_init(&fs_info->block_group_cache_lock);
2326	fs_info->block_group_cache_tree = RB_ROOT;
2327	fs_info->first_logical_byte = (u64)-1;
2328
2329	extent_io_tree_init(&fs_info->freed_extents[0],
2330			     fs_info->btree_inode->i_mapping);
2331	extent_io_tree_init(&fs_info->freed_extents[1],
2332			     fs_info->btree_inode->i_mapping);
2333	fs_info->pinned_extents = &fs_info->freed_extents[0];
2334	fs_info->do_barriers = 1;
2335
2336
2337	mutex_init(&fs_info->ordered_operations_mutex);
2338	mutex_init(&fs_info->ordered_extent_flush_mutex);
2339	mutex_init(&fs_info->tree_log_mutex);
2340	mutex_init(&fs_info->chunk_mutex);
2341	mutex_init(&fs_info->transaction_kthread_mutex);
2342	mutex_init(&fs_info->cleaner_mutex);
2343	mutex_init(&fs_info->volume_mutex);
2344	init_rwsem(&fs_info->commit_root_sem);
2345	init_rwsem(&fs_info->cleanup_work_sem);
2346	init_rwsem(&fs_info->subvol_sem);
2347	sema_init(&fs_info->uuid_tree_rescan_sem, 1);
2348	fs_info->dev_replace.lock_owner = 0;
2349	atomic_set(&fs_info->dev_replace.nesting_level, 0);
2350	mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount);
2351	mutex_init(&fs_info->dev_replace.lock_management_lock);
2352	mutex_init(&fs_info->dev_replace.lock);
2353
2354	spin_lock_init(&fs_info->qgroup_lock);
2355	mutex_init(&fs_info->qgroup_ioctl_lock);
2356	fs_info->qgroup_tree = RB_ROOT;
2357	INIT_LIST_HEAD(&fs_info->dirty_qgroups);
2358	fs_info->qgroup_seq = 1;
2359	fs_info->quota_enabled = 0;
2360	fs_info->pending_quota_state = 0;
2361	fs_info->qgroup_ulist = NULL;
2362	mutex_init(&fs_info->qgroup_rescan_lock);
2363
2364	btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
2365	btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
2366
2367	init_waitqueue_head(&fs_info->transaction_throttle);
2368	init_waitqueue_head(&fs_info->transaction_wait);
2369	init_waitqueue_head(&fs_info->transaction_blocked_wait);
2370	init_waitqueue_head(&fs_info->async_submit_wait);
 
 
 
 
 
 
 
 
 
 
 
2371
2372	ret = btrfs_alloc_stripe_hash_table(fs_info);
2373	if (ret) {
2374		err = ret;
2375		goto fail_alloc;
2376	}
2377
2378	__setup_root(4096, 4096, 4096, 4096, tree_root,
2379		     fs_info, BTRFS_ROOT_TREE_OBJECTID);
2380
2381	invalidate_bdev(fs_devices->latest_bdev);
2382
2383	/*
2384	 * Read super block and check the signature bytes only
2385	 */
2386	bh = btrfs_read_dev_super(fs_devices->latest_bdev);
2387	if (!bh) {
 
 
 
 
 
 
 
 
 
 
 
 
2388		err = -EINVAL;
 
 
 
 
 
 
 
2389		goto fail_alloc;
2390	}
2391
2392	/*
2393	 * We want to check superblock checksum, the type is stored inside.
2394	 * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k).
2395	 */
2396	if (btrfs_check_super_csum(bh->b_data)) {
2397		printk(KERN_ERR "BTRFS: superblock checksum mismatch\n");
2398		err = -EINVAL;
2399		goto fail_alloc;
 
2400	}
2401
2402	/*
2403	 * super_copy is zeroed at allocation time and we never touch the
2404	 * following bytes up to INFO_SIZE, the checksum is calculated from
2405	 * the whole block of INFO_SIZE
2406	 */
2407	memcpy(fs_info->super_copy, bh->b_data, sizeof(*fs_info->super_copy));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2408	memcpy(fs_info->super_for_commit, fs_info->super_copy,
2409	       sizeof(*fs_info->super_for_commit));
2410	brelse(bh);
2411
2412	memcpy(fs_info->fsid, fs_info->super_copy->fsid, BTRFS_FSID_SIZE);
2413
2414	ret = btrfs_check_super_valid(fs_info, sb->s_flags & MS_RDONLY);
2415	if (ret) {
2416		printk(KERN_ERR "BTRFS: superblock contains fatal errors\n");
2417		err = -EINVAL;
2418		goto fail_alloc;
2419	}
2420
2421	disk_super = fs_info->super_copy;
2422	if (!btrfs_super_root(disk_super))
2423		goto fail_alloc;
2424
2425	/* check FS state, whether FS is broken. */
2426	if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
2427		set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state);
2428
2429	/*
2430	 * run through our array of backup supers and setup
2431	 * our ring pointer to the oldest one
2432	 */
2433	generation = btrfs_super_generation(disk_super);
2434	find_oldest_super_backup(fs_info, generation);
2435
2436	/*
2437	 * In the long term, we'll store the compression type in the super
2438	 * block, and it'll be used for per file compression control.
2439	 */
2440	fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
2441
2442	ret = btrfs_parse_options(tree_root, options);
2443	if (ret) {
2444		err = ret;
2445		goto fail_alloc;
2446	}
2447
2448	features = btrfs_super_incompat_flags(disk_super) &
2449		~BTRFS_FEATURE_INCOMPAT_SUPP;
2450	if (features) {
2451		printk(KERN_ERR "BTRFS: couldn't mount because of "
2452		       "unsupported optional features (%Lx).\n",
2453		       features);
2454		err = -EINVAL;
2455		goto fail_alloc;
2456	}
2457
2458	if (btrfs_super_leafsize(disk_super) !=
2459	    btrfs_super_nodesize(disk_super)) {
2460		printk(KERN_ERR "BTRFS: couldn't mount because metadata "
2461		       "blocksizes don't match.  node %d leaf %d\n",
2462		       btrfs_super_nodesize(disk_super),
2463		       btrfs_super_leafsize(disk_super));
2464		err = -EINVAL;
2465		goto fail_alloc;
2466	}
2467	if (btrfs_super_leafsize(disk_super) > BTRFS_MAX_METADATA_BLOCKSIZE) {
2468		printk(KERN_ERR "BTRFS: couldn't mount because metadata "
2469		       "blocksize (%d) was too large\n",
2470		       btrfs_super_leafsize(disk_super));
2471		err = -EINVAL;
2472		goto fail_alloc;
2473	}
2474
2475	features = btrfs_super_incompat_flags(disk_super);
2476	features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
2477	if (tree_root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
2478		features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
 
 
2479
2480	if (features & BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA)
2481		printk(KERN_ERR "BTRFS: has skinny extents\n");
2482
2483	/*
2484	 * flag our filesystem as having big metadata blocks if
2485	 * they are bigger than the page size
2486	 */
2487	if (btrfs_super_leafsize(disk_super) > PAGE_CACHE_SIZE) {
2488		if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA))
2489			printk(KERN_INFO "BTRFS: flagging fs with big metadata feature\n");
 
2490		features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
2491	}
2492
2493	nodesize = btrfs_super_nodesize(disk_super);
2494	leafsize = btrfs_super_leafsize(disk_super);
2495	sectorsize = btrfs_super_sectorsize(disk_super);
2496	stripesize = btrfs_super_stripesize(disk_super);
2497	fs_info->dirty_metadata_batch = leafsize * (1 + ilog2(nr_cpu_ids));
2498	fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
2499
 
 
 
 
 
2500	/*
2501	 * mixed block groups end up with duplicate but slightly offset
2502	 * extent buffers for the same range.  It leads to corruptions
2503	 */
2504	if ((features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
2505	    (sectorsize != leafsize)) {
2506		printk(KERN_WARNING "BTRFS: unequal leaf/node/sector sizes "
2507				"are not allowed for mixed block groups on %s\n",
2508				sb->s_id);
2509		goto fail_alloc;
2510	}
2511
2512	/*
2513	 * Needn't use the lock because there is no other task which will
2514	 * update the flag.
2515	 */
2516	btrfs_set_super_incompat_flags(disk_super, features);
2517
2518	features = btrfs_super_compat_ro_flags(disk_super) &
2519		~BTRFS_FEATURE_COMPAT_RO_SUPP;
2520	if (!(sb->s_flags & MS_RDONLY) && features) {
2521		printk(KERN_ERR "BTRFS: couldn't mount RDWR because of "
2522		       "unsupported option features (%Lx).\n",
2523		       features);
2524		err = -EINVAL;
2525		goto fail_alloc;
2526	}
2527
2528	max_active = fs_info->thread_pool_size;
2529
2530	fs_info->workers =
2531		btrfs_alloc_workqueue("worker", flags | WQ_HIGHPRI,
2532				      max_active, 16);
2533
2534	fs_info->delalloc_workers =
2535		btrfs_alloc_workqueue("delalloc", flags, max_active, 2);
2536
2537	fs_info->flush_workers =
2538		btrfs_alloc_workqueue("flush_delalloc", flags, max_active, 0);
2539
2540	fs_info->caching_workers =
2541		btrfs_alloc_workqueue("cache", flags, max_active, 0);
2542
2543	/*
2544	 * a higher idle thresh on the submit workers makes it much more
2545	 * likely that bios will be send down in a sane order to the
2546	 * devices
2547	 */
2548	fs_info->submit_workers =
2549		btrfs_alloc_workqueue("submit", flags,
2550				      min_t(u64, fs_devices->num_devices,
2551					    max_active), 64);
2552
2553	fs_info->fixup_workers =
2554		btrfs_alloc_workqueue("fixup", flags, 1, 0);
2555
2556	/*
2557	 * endios are largely parallel and should have a very
2558	 * low idle thresh
2559	 */
2560	fs_info->endio_workers =
2561		btrfs_alloc_workqueue("endio", flags, max_active, 4);
2562	fs_info->endio_meta_workers =
2563		btrfs_alloc_workqueue("endio-meta", flags, max_active, 4);
2564	fs_info->endio_meta_write_workers =
2565		btrfs_alloc_workqueue("endio-meta-write", flags, max_active, 2);
2566	fs_info->endio_raid56_workers =
2567		btrfs_alloc_workqueue("endio-raid56", flags, max_active, 4);
2568	fs_info->rmw_workers =
2569		btrfs_alloc_workqueue("rmw", flags, max_active, 2);
2570	fs_info->endio_write_workers =
2571		btrfs_alloc_workqueue("endio-write", flags, max_active, 2);
2572	fs_info->endio_freespace_worker =
2573		btrfs_alloc_workqueue("freespace-write", flags, max_active, 0);
2574	fs_info->delayed_workers =
2575		btrfs_alloc_workqueue("delayed-meta", flags, max_active, 0);
2576	fs_info->readahead_workers =
2577		btrfs_alloc_workqueue("readahead", flags, max_active, 2);
2578	fs_info->qgroup_rescan_workers =
2579		btrfs_alloc_workqueue("qgroup-rescan", flags, 1, 0);
2580
2581	if (!(fs_info->workers && fs_info->delalloc_workers &&
2582	      fs_info->submit_workers && fs_info->flush_workers &&
2583	      fs_info->endio_workers && fs_info->endio_meta_workers &&
2584	      fs_info->endio_meta_write_workers &&
2585	      fs_info->endio_write_workers && fs_info->endio_raid56_workers &&
2586	      fs_info->endio_freespace_worker && fs_info->rmw_workers &&
2587	      fs_info->caching_workers && fs_info->readahead_workers &&
2588	      fs_info->fixup_workers && fs_info->delayed_workers &&
2589	      fs_info->qgroup_rescan_workers)) {
2590		err = -ENOMEM;
2591		goto fail_sb_buffer;
2592	}
2593
2594	fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
2595	fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
2596				    4 * 1024 * 1024 / PAGE_CACHE_SIZE);
2597
2598	tree_root->nodesize = nodesize;
2599	tree_root->leafsize = leafsize;
2600	tree_root->sectorsize = sectorsize;
2601	tree_root->stripesize = stripesize;
2602
2603	sb->s_blocksize = sectorsize;
2604	sb->s_blocksize_bits = blksize_bits(sectorsize);
2605
2606	if (btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
2607		printk(KERN_INFO "BTRFS: valid FS not found on %s\n", sb->s_id);
2608		goto fail_sb_buffer;
2609	}
2610
2611	if (sectorsize != PAGE_SIZE) {
2612		printk(KERN_WARNING "BTRFS: Incompatible sector size(%lu) "
2613		       "found on %s\n", (unsigned long)sectorsize, sb->s_id);
2614		goto fail_sb_buffer;
2615	}
2616
2617	mutex_lock(&fs_info->chunk_mutex);
2618	ret = btrfs_read_sys_array(tree_root);
2619	mutex_unlock(&fs_info->chunk_mutex);
2620	if (ret) {
2621		printk(KERN_WARNING "BTRFS: failed to read the system "
2622		       "array on %s\n", sb->s_id);
2623		goto fail_sb_buffer;
2624	}
2625
2626	blocksize = btrfs_level_size(tree_root,
2627				     btrfs_super_chunk_root_level(disk_super));
2628	generation = btrfs_super_chunk_root_generation(disk_super);
 
2629
2630	__setup_root(nodesize, leafsize, sectorsize, stripesize,
2631		     chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
2632
2633	chunk_root->node = read_tree_block(chunk_root,
2634					   btrfs_super_chunk_root(disk_super),
2635					   blocksize, generation);
2636	if (!chunk_root->node ||
2637	    !test_bit(EXTENT_BUFFER_UPTODATE, &chunk_root->node->bflags)) {
2638		printk(KERN_WARNING "BTRFS: failed to read chunk root on %s\n",
2639		       sb->s_id);
 
 
2640		goto fail_tree_roots;
2641	}
2642	btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
2643	chunk_root->commit_root = btrfs_root_node(chunk_root);
2644
2645	read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
2646	   btrfs_header_chunk_tree_uuid(chunk_root->node), BTRFS_UUID_SIZE);
2647
2648	ret = btrfs_read_chunk_tree(chunk_root);
2649	if (ret) {
2650		printk(KERN_WARNING "BTRFS: failed to read chunk tree on %s\n",
2651		       sb->s_id);
2652		goto fail_tree_roots;
2653	}
2654
2655	/*
2656	 * keep the device that is marked to be the target device for the
2657	 * dev_replace procedure
2658	 */
2659	btrfs_close_extra_devices(fs_info, fs_devices, 0);
2660
2661	if (!fs_devices->latest_bdev) {
2662		printk(KERN_CRIT "BTRFS: failed to read devices on %s\n",
2663		       sb->s_id);
2664		goto fail_tree_roots;
2665	}
2666
2667retry_root_backup:
2668	blocksize = btrfs_level_size(tree_root,
2669				     btrfs_super_root_level(disk_super));
2670	generation = btrfs_super_generation(disk_super);
 
2671
2672	tree_root->node = read_tree_block(tree_root,
2673					  btrfs_super_root(disk_super),
2674					  blocksize, generation);
2675	if (!tree_root->node ||
2676	    !test_bit(EXTENT_BUFFER_UPTODATE, &tree_root->node->bflags)) {
2677		printk(KERN_WARNING "BTRFS: failed to read tree root on %s\n",
2678		       sb->s_id);
2679
 
2680		goto recovery_tree_root;
2681	}
2682
2683	btrfs_set_root_node(&tree_root->root_item, tree_root->node);
2684	tree_root->commit_root = btrfs_root_node(tree_root);
2685	btrfs_set_root_refs(&tree_root->root_item, 1);
2686
2687	location.objectid = BTRFS_EXTENT_TREE_OBJECTID;
2688	location.type = BTRFS_ROOT_ITEM_KEY;
2689	location.offset = 0;
2690
2691	extent_root = btrfs_read_tree_root(tree_root, &location);
2692	if (IS_ERR(extent_root)) {
2693		ret = PTR_ERR(extent_root);
2694		goto recovery_tree_root;
2695	}
2696	extent_root->track_dirty = 1;
2697	fs_info->extent_root = extent_root;
2698
2699	location.objectid = BTRFS_DEV_TREE_OBJECTID;
2700	dev_root = btrfs_read_tree_root(tree_root, &location);
2701	if (IS_ERR(dev_root)) {
2702		ret = PTR_ERR(dev_root);
2703		goto recovery_tree_root;
2704	}
2705	dev_root->track_dirty = 1;
2706	fs_info->dev_root = dev_root;
2707	btrfs_init_devices_late(fs_info);
2708
2709	location.objectid = BTRFS_CSUM_TREE_OBJECTID;
2710	csum_root = btrfs_read_tree_root(tree_root, &location);
2711	if (IS_ERR(csum_root)) {
2712		ret = PTR_ERR(csum_root);
2713		goto recovery_tree_root;
2714	}
2715	csum_root->track_dirty = 1;
2716	fs_info->csum_root = csum_root;
2717
2718	location.objectid = BTRFS_QUOTA_TREE_OBJECTID;
2719	quota_root = btrfs_read_tree_root(tree_root, &location);
2720	if (!IS_ERR(quota_root)) {
2721		quota_root->track_dirty = 1;
2722		fs_info->quota_enabled = 1;
2723		fs_info->pending_quota_state = 1;
2724		fs_info->quota_root = quota_root;
2725	}
2726
2727	location.objectid = BTRFS_UUID_TREE_OBJECTID;
2728	uuid_root = btrfs_read_tree_root(tree_root, &location);
2729	if (IS_ERR(uuid_root)) {
2730		ret = PTR_ERR(uuid_root);
2731		if (ret != -ENOENT)
2732			goto recovery_tree_root;
2733		create_uuid_tree = true;
2734		check_uuid_tree = false;
2735	} else {
2736		uuid_root->track_dirty = 1;
2737		fs_info->uuid_root = uuid_root;
2738		create_uuid_tree = false;
2739		check_uuid_tree =
2740		    generation != btrfs_super_uuid_tree_generation(disk_super);
2741	}
2742
2743	fs_info->generation = generation;
2744	fs_info->last_trans_committed = generation;
2745
 
 
 
 
 
 
 
2746	ret = btrfs_recover_balance(fs_info);
2747	if (ret) {
2748		printk(KERN_WARNING "BTRFS: failed to recover balance\n");
2749		goto fail_block_groups;
2750	}
2751
2752	ret = btrfs_init_dev_stats(fs_info);
2753	if (ret) {
2754		printk(KERN_ERR "BTRFS: failed to init dev_stats: %d\n",
2755		       ret);
2756		goto fail_block_groups;
2757	}
2758
2759	ret = btrfs_init_dev_replace(fs_info);
2760	if (ret) {
2761		pr_err("BTRFS: failed to init dev_replace: %d\n", ret);
2762		goto fail_block_groups;
2763	}
2764
2765	btrfs_close_extra_devices(fs_info, fs_devices, 1);
2766
2767	ret = btrfs_sysfs_add_one(fs_info);
2768	if (ret) {
2769		pr_err("BTRFS: failed to init sysfs interface: %d\n", ret);
 
2770		goto fail_block_groups;
2771	}
2772
 
 
 
 
 
 
 
 
 
 
 
 
 
2773	ret = btrfs_init_space_info(fs_info);
2774	if (ret) {
2775		printk(KERN_ERR "BTRFS: Failed to initial space info: %d\n", ret);
2776		goto fail_sysfs;
2777	}
2778
2779	ret = btrfs_read_block_groups(extent_root);
2780	if (ret) {
2781		printk(KERN_ERR "BTRFS: Failed to read block groups: %d\n", ret);
2782		goto fail_sysfs;
2783	}
2784	fs_info->num_tolerated_disk_barrier_failures =
2785		btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
2786	if (fs_info->fs_devices->missing_devices >
2787	     fs_info->num_tolerated_disk_barrier_failures &&
2788	    !(sb->s_flags & MS_RDONLY)) {
2789		printk(KERN_WARNING "BTRFS: "
2790			"too many missing devices, writeable mount is not allowed\n");
2791		goto fail_sysfs;
2792	}
2793
2794	fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
2795					       "btrfs-cleaner");
2796	if (IS_ERR(fs_info->cleaner_kthread))
2797		goto fail_sysfs;
2798
2799	fs_info->transaction_kthread = kthread_run(transaction_kthread,
2800						   tree_root,
2801						   "btrfs-transaction");
2802	if (IS_ERR(fs_info->transaction_kthread))
2803		goto fail_cleaner;
2804
2805	if (!btrfs_test_opt(tree_root, SSD) &&
2806	    !btrfs_test_opt(tree_root, NOSSD) &&
2807	    !fs_info->fs_devices->rotating) {
2808		printk(KERN_INFO "BTRFS: detected SSD devices, enabling SSD "
2809		       "mode\n");
2810		btrfs_set_opt(fs_info->mount_opt, SSD);
2811	}
2812
2813	/* Set the real inode map cache flag */
2814	if (btrfs_test_opt(tree_root, CHANGE_INODE_CACHE))
2815		btrfs_set_opt(tree_root->fs_info->mount_opt, INODE_MAP_CACHE);
 
 
2816
2817#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
2818	if (btrfs_test_opt(tree_root, CHECK_INTEGRITY)) {
2819		ret = btrfsic_mount(tree_root, fs_devices,
2820				    btrfs_test_opt(tree_root,
2821					CHECK_INTEGRITY_INCLUDING_EXTENT_DATA) ?
2822				    1 : 0,
2823				    fs_info->check_integrity_print_mask);
2824		if (ret)
2825			printk(KERN_WARNING "BTRFS: failed to initialize"
2826			       " integrity check module %s\n", sb->s_id);
 
2827	}
2828#endif
2829	ret = btrfs_read_qgroup_config(fs_info);
2830	if (ret)
2831		goto fail_trans_kthread;
2832
2833	/* do not make disk changes in broken FS */
2834	if (btrfs_super_log_root(disk_super) != 0) {
2835		u64 bytenr = btrfs_super_log_root(disk_super);
2836
2837		if (fs_devices->rw_devices == 0) {
2838			printk(KERN_WARNING "BTRFS: log replay required "
2839			       "on RO media\n");
2840			err = -EIO;
2841			goto fail_qgroup;
2842		}
2843		blocksize =
2844		     btrfs_level_size(tree_root,
2845				      btrfs_super_log_root_level(disk_super));
2846
2847		log_tree_root = btrfs_alloc_root(fs_info);
2848		if (!log_tree_root) {
2849			err = -ENOMEM;
2850			goto fail_qgroup;
2851		}
2852
2853		__setup_root(nodesize, leafsize, sectorsize, stripesize,
2854			     log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
2855
2856		log_tree_root->node = read_tree_block(tree_root, bytenr,
2857						      blocksize,
2858						      generation + 1);
2859		if (!log_tree_root->node ||
2860		    !extent_buffer_uptodate(log_tree_root->node)) {
2861			printk(KERN_ERR "BTRFS: failed to read log tree\n");
2862			free_extent_buffer(log_tree_root->node);
2863			kfree(log_tree_root);
2864			goto fail_qgroup;
2865		}
2866		/* returns with log_tree_root freed on success */
2867		ret = btrfs_recover_log_trees(log_tree_root);
2868		if (ret) {
2869			btrfs_error(tree_root->fs_info, ret,
2870				    "Failed to recover log tree");
2871			free_extent_buffer(log_tree_root->node);
2872			kfree(log_tree_root);
2873			goto fail_qgroup;
2874		}
2875
2876		if (sb->s_flags & MS_RDONLY) {
2877			ret = btrfs_commit_super(tree_root);
2878			if (ret)
2879				goto fail_qgroup;
2880		}
2881	}
2882
2883	ret = btrfs_find_orphan_roots(tree_root);
2884	if (ret)
2885		goto fail_qgroup;
2886
2887	if (!(sb->s_flags & MS_RDONLY)) {
2888		ret = btrfs_cleanup_fs_roots(fs_info);
2889		if (ret)
2890			goto fail_qgroup;
2891
 
2892		ret = btrfs_recover_relocation(tree_root);
 
2893		if (ret < 0) {
2894			printk(KERN_WARNING
2895			       "BTRFS: failed to recover relocation\n");
2896			err = -EINVAL;
2897			goto fail_qgroup;
2898		}
2899	}
2900
2901	location.objectid = BTRFS_FS_TREE_OBJECTID;
2902	location.type = BTRFS_ROOT_ITEM_KEY;
2903	location.offset = 0;
2904
2905	fs_info->fs_root = btrfs_read_fs_root_no_name(fs_info, &location);
2906	if (IS_ERR(fs_info->fs_root)) {
2907		err = PTR_ERR(fs_info->fs_root);
 
2908		goto fail_qgroup;
2909	}
2910
2911	if (sb->s_flags & MS_RDONLY)
2912		return 0;
2913
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2914	down_read(&fs_info->cleanup_work_sem);
2915	if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) ||
2916	    (ret = btrfs_orphan_cleanup(fs_info->tree_root))) {
2917		up_read(&fs_info->cleanup_work_sem);
2918		close_ctree(tree_root);
2919		return ret;
2920	}
2921	up_read(&fs_info->cleanup_work_sem);
2922
2923	ret = btrfs_resume_balance_async(fs_info);
2924	if (ret) {
2925		printk(KERN_WARNING "BTRFS: failed to resume balance\n");
2926		close_ctree(tree_root);
2927		return ret;
2928	}
2929
2930	ret = btrfs_resume_dev_replace_async(fs_info);
2931	if (ret) {
2932		pr_warn("BTRFS: failed to resume dev_replace\n");
2933		close_ctree(tree_root);
2934		return ret;
2935	}
2936
2937	btrfs_qgroup_rescan_resume(fs_info);
2938
2939	if (create_uuid_tree) {
2940		pr_info("BTRFS: creating UUID tree\n");
2941		ret = btrfs_create_uuid_tree(fs_info);
2942		if (ret) {
2943			pr_warn("BTRFS: failed to create the UUID tree %d\n",
2944				ret);
2945			close_ctree(tree_root);
2946			return ret;
2947		}
2948	} else if (check_uuid_tree ||
2949		   btrfs_test_opt(tree_root, RESCAN_UUID_TREE)) {
2950		pr_info("BTRFS: checking UUID tree\n");
 
2951		ret = btrfs_check_uuid_tree(fs_info);
2952		if (ret) {
2953			pr_warn("BTRFS: failed to check the UUID tree %d\n",
2954				ret);
2955			close_ctree(tree_root);
2956			return ret;
2957		}
2958	} else {
2959		fs_info->update_uuid_tree_gen = 1;
2960	}
 
 
 
 
 
 
 
2961
2962	return 0;
2963
2964fail_qgroup:
2965	btrfs_free_qgroup_config(fs_info);
2966fail_trans_kthread:
2967	kthread_stop(fs_info->transaction_kthread);
2968	btrfs_cleanup_transaction(fs_info->tree_root);
2969	del_fs_roots(fs_info);
2970fail_cleaner:
2971	kthread_stop(fs_info->cleaner_kthread);
2972
2973	/*
2974	 * make sure we're done with the btree inode before we stop our
2975	 * kthreads
2976	 */
2977	filemap_write_and_wait(fs_info->btree_inode->i_mapping);
2978
2979fail_sysfs:
2980	btrfs_sysfs_remove_one(fs_info);
 
 
 
2981
2982fail_block_groups:
2983	btrfs_put_block_group_cache(fs_info);
2984	btrfs_free_block_groups(fs_info);
2985
2986fail_tree_roots:
2987	free_root_pointers(fs_info, 1);
2988	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
2989
2990fail_sb_buffer:
2991	btrfs_stop_all_workers(fs_info);
 
 
 
2992fail_alloc:
2993fail_iput:
2994	btrfs_mapping_tree_free(&fs_info->mapping_tree);
2995
2996	iput(fs_info->btree_inode);
2997fail_bio_counter:
2998	percpu_counter_destroy(&fs_info->bio_counter);
2999fail_delalloc_bytes:
3000	percpu_counter_destroy(&fs_info->delalloc_bytes);
3001fail_dirty_metadata_bytes:
3002	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
3003fail_bdi:
3004	bdi_destroy(&fs_info->bdi);
3005fail_srcu:
3006	cleanup_srcu_struct(&fs_info->subvol_srcu);
3007fail:
3008	btrfs_free_stripe_hash_table(fs_info);
3009	btrfs_close_devices(fs_info->fs_devices);
3010	return err;
3011
3012recovery_tree_root:
3013	if (!btrfs_test_opt(tree_root, RECOVERY))
3014		goto fail_tree_roots;
3015
3016	free_root_pointers(fs_info, 0);
3017
3018	/* don't use the log in recovery mode, it won't be valid */
3019	btrfs_set_super_log_root(disk_super, 0);
3020
3021	/* we can't trust the free space cache either */
3022	btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
3023
3024	ret = next_root_backup(fs_info, fs_info->super_copy,
3025			       &num_backups_tried, &backup_index);
3026	if (ret == -1)
3027		goto fail_block_groups;
3028	goto retry_root_backup;
3029}
 
3030
3031static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
3032{
3033	if (uptodate) {
3034		set_buffer_uptodate(bh);
3035	} else {
3036		struct btrfs_device *device = (struct btrfs_device *)
3037			bh->b_private;
3038
3039		printk_ratelimited_in_rcu(KERN_WARNING "BTRFS: lost page write due to "
3040					  "I/O error on %s\n",
3041					  rcu_str_deref(device->name));
3042		/* note, we dont' set_buffer_write_io_error because we have
3043		 * our own ways of dealing with the IO errors
3044		 */
3045		clear_buffer_uptodate(bh);
3046		btrfs_dev_stat_inc_and_print(device, BTRFS_DEV_STAT_WRITE_ERRS);
3047	}
3048	unlock_buffer(bh);
3049	put_bh(bh);
3050}
3051
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3052struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
3053{
3054	struct buffer_head *bh;
3055	struct buffer_head *latest = NULL;
3056	struct btrfs_super_block *super;
3057	int i;
3058	u64 transid = 0;
3059	u64 bytenr;
3060
3061	/* we would like to check all the supers, but that would make
3062	 * a btrfs mount succeed after a mkfs from a different FS.
3063	 * So, we need to add a special mount option to scan for
3064	 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
3065	 */
3066	for (i = 0; i < 1; i++) {
3067		bytenr = btrfs_sb_offset(i);
3068		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
3069					i_size_read(bdev->bd_inode))
3070			break;
3071		bh = __bread(bdev, bytenr / 4096,
3072					BTRFS_SUPER_INFO_SIZE);
3073		if (!bh)
3074			continue;
3075
3076		super = (struct btrfs_super_block *)bh->b_data;
3077		if (btrfs_super_bytenr(super) != bytenr ||
3078		    btrfs_super_magic(super) != BTRFS_MAGIC) {
3079			brelse(bh);
3080			continue;
3081		}
3082
3083		if (!latest || btrfs_super_generation(super) > transid) {
3084			brelse(latest);
3085			latest = bh;
3086			transid = btrfs_super_generation(super);
3087		} else {
3088			brelse(bh);
3089		}
3090	}
 
 
 
 
3091	return latest;
3092}
3093
3094/*
3095 * this should be called twice, once with wait == 0 and
3096 * once with wait == 1.  When wait == 0 is done, all the buffer heads
3097 * we write are pinned.
3098 *
3099 * They are released when wait == 1 is done.
3100 * max_mirrors must be the same for both runs, and it indicates how
3101 * many supers on this one device should be written.
3102 *
3103 * max_mirrors == 0 means to write them all.
3104 */
3105static int write_dev_supers(struct btrfs_device *device,
3106			    struct btrfs_super_block *sb,
3107			    int do_barriers, int wait, int max_mirrors)
3108{
 
 
3109	struct buffer_head *bh;
3110	int i;
3111	int ret;
3112	int errors = 0;
3113	u32 crc;
3114	u64 bytenr;
 
3115
3116	if (max_mirrors == 0)
3117		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
3118
 
 
3119	for (i = 0; i < max_mirrors; i++) {
3120		bytenr = btrfs_sb_offset(i);
3121		if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->total_bytes)
 
3122			break;
3123
3124		if (wait) {
3125			bh = __find_get_block(device->bdev, bytenr / 4096,
3126					      BTRFS_SUPER_INFO_SIZE);
3127			if (!bh) {
3128				errors++;
3129				continue;
3130			}
3131			wait_on_buffer(bh);
3132			if (!buffer_uptodate(bh))
3133				errors++;
3134
3135			/* drop our reference */
3136			brelse(bh);
3137
3138			/* drop the reference from the wait == 0 run */
3139			brelse(bh);
 
 
 
 
 
 
 
 
3140			continue;
3141		} else {
3142			btrfs_set_super_bytenr(sb, bytenr);
3143
3144			crc = ~(u32)0;
3145			crc = btrfs_csum_data((char *)sb +
3146					      BTRFS_CSUM_SIZE, crc,
3147					      BTRFS_SUPER_INFO_SIZE -
3148					      BTRFS_CSUM_SIZE);
3149			btrfs_csum_final(crc, sb->csum);
3150
3151			/*
3152			 * one reference for us, and we leave it for the
3153			 * caller
3154			 */
3155			bh = __getblk(device->bdev, bytenr / 4096,
3156				      BTRFS_SUPER_INFO_SIZE);
3157			if (!bh) {
3158				printk(KERN_ERR "BTRFS: couldn't get super "
3159				       "buffer head for bytenr %Lu\n", bytenr);
3160				errors++;
3161				continue;
3162			}
3163
3164			memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
3165
3166			/* one reference for submit_bh */
3167			get_bh(bh);
3168
3169			set_buffer_uptodate(bh);
3170			lock_buffer(bh);
3171			bh->b_end_io = btrfs_end_buffer_write_sync;
3172			bh->b_private = device;
3173		}
3174
3175		/*
3176		 * we fua the first super.  The others we allow
3177		 * to go down lazy.
3178		 */
3179		if (i == 0)
3180			ret = btrfsic_submit_bh(WRITE_FUA, bh);
3181		else
3182			ret = btrfsic_submit_bh(WRITE_SYNC, bh);
3183		if (ret)
3184			errors++;
3185	}
3186	return errors < i ? 0 : -1;
3187}
3188
3189/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3190 * endio for the write_dev_flush, this will wake anyone waiting
3191 * for the barrier when it is done
3192 */
3193static void btrfs_end_empty_barrier(struct bio *bio, int err)
3194{
3195	if (err) {
3196		if (err == -EOPNOTSUPP)
3197			set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
3198		clear_bit(BIO_UPTODATE, &bio->bi_flags);
3199	}
3200	if (bio->bi_private)
3201		complete(bio->bi_private);
3202	bio_put(bio);
3203}
3204
3205/*
3206 * trigger flushes for one the devices.  If you pass wait == 0, the flushes are
3207 * sent down.  With wait == 1, it waits for the previous flush.
3208 *
3209 * any device where the flush fails with eopnotsupp are flagged as not-barrier
3210 * capable
3211 */
3212static int write_dev_flush(struct btrfs_device *device, int wait)
3213{
3214	struct bio *bio;
3215	int ret = 0;
3216
3217	if (device->nobarriers)
3218		return 0;
3219
3220	if (wait) {
3221		bio = device->flush_bio;
3222		if (!bio)
3223			return 0;
 
 
3224
3225		wait_for_completion(&device->flush_wait);
 
 
3226
3227		if (bio_flagged(bio, BIO_EOPNOTSUPP)) {
3228			printk_in_rcu("BTRFS: disabling barriers on dev %s\n",
3229				      rcu_str_deref(device->name));
3230			device->nobarriers = 1;
3231		} else if (!bio_flagged(bio, BIO_UPTODATE)) {
3232			ret = -EIO;
3233			btrfs_dev_stat_inc_and_print(device,
3234				BTRFS_DEV_STAT_FLUSH_ERRS);
3235		}
3236
3237		/* drop the reference from the wait == 0 run */
3238		bio_put(bio);
3239		device->flush_bio = NULL;
3240
3241		return ret;
3242	}
3243
3244	/*
3245	 * one reference for us, and we leave it for the
3246	 * caller
3247	 */
3248	device->flush_bio = NULL;
3249	bio = btrfs_io_bio_alloc(GFP_NOFS, 0);
3250	if (!bio)
3251		return -ENOMEM;
3252
3253	bio->bi_end_io = btrfs_end_empty_barrier;
3254	bio->bi_bdev = device->bdev;
3255	init_completion(&device->flush_wait);
3256	bio->bi_private = &device->flush_wait;
3257	device->flush_bio = bio;
3258
3259	bio_get(bio);
3260	btrfsic_submit_bio(WRITE_FLUSH, bio);
3261
 
 
 
 
3262	return 0;
3263}
3264
3265/*
3266 * send an empty flush down to each device in parallel,
3267 * then wait for them
3268 */
3269static int barrier_all_devices(struct btrfs_fs_info *info)
3270{
3271	struct list_head *head;
3272	struct btrfs_device *dev;
3273	int errors_send = 0;
3274	int errors_wait = 0;
3275	int ret;
3276
 
3277	/* send down all the barriers */
3278	head = &info->fs_devices->devices;
3279	list_for_each_entry_rcu(dev, head, dev_list) {
3280		if (dev->missing)
3281			continue;
3282		if (!dev->bdev) {
3283			errors_send++;
3284			continue;
3285		}
3286		if (!dev->in_fs_metadata || !dev->writeable)
3287			continue;
3288
3289		ret = write_dev_flush(dev, 0);
3290		if (ret)
3291			errors_send++;
3292	}
3293
3294	/* wait for all the barriers */
3295	list_for_each_entry_rcu(dev, head, dev_list) {
3296		if (dev->missing)
3297			continue;
3298		if (!dev->bdev) {
3299			errors_wait++;
3300			continue;
3301		}
3302		if (!dev->in_fs_metadata || !dev->writeable)
 
3303			continue;
3304
3305		ret = write_dev_flush(dev, 1);
3306		if (ret)
 
 
 
3307			errors_wait++;
 
 
 
 
 
 
 
 
 
 
3308	}
3309	if (errors_send > info->num_tolerated_disk_barrier_failures ||
3310	    errors_wait > info->num_tolerated_disk_barrier_failures)
3311		return -EIO;
3312	return 0;
3313}
3314
3315int btrfs_calc_num_tolerated_disk_barrier_failures(
3316	struct btrfs_fs_info *fs_info)
3317{
3318	struct btrfs_ioctl_space_info space;
3319	struct btrfs_space_info *sinfo;
3320	u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
3321		       BTRFS_BLOCK_GROUP_SYSTEM,
3322		       BTRFS_BLOCK_GROUP_METADATA,
3323		       BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
3324	int num_types = 4;
3325	int i;
3326	int c;
3327	int num_tolerated_disk_barrier_failures =
3328		(int)fs_info->fs_devices->num_devices;
3329
3330	for (i = 0; i < num_types; i++) {
3331		struct btrfs_space_info *tmp;
3332
3333		sinfo = NULL;
3334		rcu_read_lock();
3335		list_for_each_entry_rcu(tmp, &fs_info->space_info, list) {
3336			if (tmp->flags == types[i]) {
3337				sinfo = tmp;
3338				break;
3339			}
3340		}
3341		rcu_read_unlock();
3342
3343		if (!sinfo)
 
 
 
3344			continue;
 
 
 
 
3345
3346		down_read(&sinfo->groups_sem);
3347		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3348			if (!list_empty(&sinfo->block_groups[c])) {
3349				u64 flags;
3350
3351				btrfs_get_block_group_info(
3352					&sinfo->block_groups[c], &space);
3353				if (space.total_bytes == 0 ||
3354				    space.used_bytes == 0)
3355					continue;
3356				flags = space.flags;
3357				/*
3358				 * return
3359				 * 0: if dup, single or RAID0 is configured for
3360				 *    any of metadata, system or data, else
3361				 * 1: if RAID5 is configured, or if RAID1 or
3362				 *    RAID10 is configured and only two mirrors
3363				 *    are used, else
3364				 * 2: if RAID6 is configured, else
3365				 * num_mirrors - 1: if RAID1 or RAID10 is
3366				 *                  configured and more than
3367				 *                  2 mirrors are used.
3368				 */
3369				if (num_tolerated_disk_barrier_failures > 0 &&
3370				    ((flags & (BTRFS_BLOCK_GROUP_DUP |
3371					       BTRFS_BLOCK_GROUP_RAID0)) ||
3372				     ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK)
3373				      == 0)))
3374					num_tolerated_disk_barrier_failures = 0;
3375				else if (num_tolerated_disk_barrier_failures > 1) {
3376					if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
3377					    BTRFS_BLOCK_GROUP_RAID5 |
3378					    BTRFS_BLOCK_GROUP_RAID10)) {
3379						num_tolerated_disk_barrier_failures = 1;
3380					} else if (flags &
3381						   BTRFS_BLOCK_GROUP_RAID6) {
3382						num_tolerated_disk_barrier_failures = 2;
3383					}
3384				}
3385			}
3386		}
3387		up_read(&sinfo->groups_sem);
3388	}
3389
3390	return num_tolerated_disk_barrier_failures;
3391}
3392
3393static int write_all_supers(struct btrfs_root *root, int max_mirrors)
3394{
3395	struct list_head *head;
3396	struct btrfs_device *dev;
3397	struct btrfs_super_block *sb;
3398	struct btrfs_dev_item *dev_item;
3399	int ret;
3400	int do_barriers;
3401	int max_errors;
3402	int total_errors = 0;
3403	u64 flags;
3404
3405	do_barriers = !btrfs_test_opt(root, NOBARRIER);
3406	backup_super_roots(root->fs_info);
3407
3408	sb = root->fs_info->super_for_commit;
 
 
 
 
 
 
 
 
3409	dev_item = &sb->dev_item;
3410
3411	mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
3412	head = &root->fs_info->fs_devices->devices;
3413	max_errors = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
3414
3415	if (do_barriers) {
3416		ret = barrier_all_devices(root->fs_info);
3417		if (ret) {
3418			mutex_unlock(
3419				&root->fs_info->fs_devices->device_list_mutex);
3420			btrfs_error(root->fs_info, ret,
3421				    "errors while submitting device barriers.");
3422			return ret;
3423		}
3424	}
3425
3426	list_for_each_entry_rcu(dev, head, dev_list) {
3427		if (!dev->bdev) {
3428			total_errors++;
3429			continue;
3430		}
3431		if (!dev->in_fs_metadata || !dev->writeable)
 
3432			continue;
3433
3434		btrfs_set_stack_device_generation(dev_item, 0);
3435		btrfs_set_stack_device_type(dev_item, dev->type);
3436		btrfs_set_stack_device_id(dev_item, dev->devid);
3437		btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
3438		btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
 
 
3439		btrfs_set_stack_device_io_align(dev_item, dev->io_align);
3440		btrfs_set_stack_device_io_width(dev_item, dev->io_width);
3441		btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
3442		memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
3443		memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
 
3444
3445		flags = btrfs_super_flags(sb);
3446		btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
3447
3448		ret = write_dev_supers(dev, sb, do_barriers, 0, max_mirrors);
 
 
 
 
 
 
 
 
3449		if (ret)
3450			total_errors++;
3451	}
3452	if (total_errors > max_errors) {
3453		btrfs_err(root->fs_info, "%d errors while writing supers",
3454		       total_errors);
3455		mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
3456
3457		/* FUA is masked off if unsupported and can't be the reason */
3458		btrfs_error(root->fs_info, -EIO,
3459			    "%d errors while writing supers", total_errors);
 
3460		return -EIO;
3461	}
3462
3463	total_errors = 0;
3464	list_for_each_entry_rcu(dev, head, dev_list) {
3465		if (!dev->bdev)
3466			continue;
3467		if (!dev->in_fs_metadata || !dev->writeable)
 
3468			continue;
3469
3470		ret = write_dev_supers(dev, sb, do_barriers, 1, max_mirrors);
3471		if (ret)
3472			total_errors++;
3473	}
3474	mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
3475	if (total_errors > max_errors) {
3476		btrfs_error(root->fs_info, -EIO,
3477			    "%d errors while writing supers", total_errors);
 
3478		return -EIO;
3479	}
3480	return 0;
3481}
3482
3483int write_ctree_super(struct btrfs_trans_handle *trans,
3484		      struct btrfs_root *root, int max_mirrors)
3485{
3486	return write_all_supers(root, max_mirrors);
3487}
3488
3489/* Drop a fs root from the radix tree and free it. */
3490void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
3491				  struct btrfs_root *root)
3492{
3493	spin_lock(&fs_info->fs_roots_radix_lock);
3494	radix_tree_delete(&fs_info->fs_roots_radix,
3495			  (unsigned long)root->root_key.objectid);
3496	spin_unlock(&fs_info->fs_roots_radix_lock);
3497
3498	if (btrfs_root_refs(&root->root_item) == 0)
3499		synchronize_srcu(&fs_info->subvol_srcu);
3500
3501	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
3502		btrfs_free_log(NULL, root);
 
 
 
 
 
 
 
3503
3504	__btrfs_remove_free_space_cache(root->free_ino_pinned);
3505	__btrfs_remove_free_space_cache(root->free_ino_ctl);
3506	free_fs_root(root);
 
 
3507}
3508
3509static void free_fs_root(struct btrfs_root *root)
3510{
3511	iput(root->cache_inode);
3512	WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
3513	btrfs_free_block_rsv(root, root->orphan_block_rsv);
3514	root->orphan_block_rsv = NULL;
3515	if (root->anon_dev)
3516		free_anon_bdev(root->anon_dev);
3517	if (root->subv_writers)
3518		btrfs_free_subvolume_writers(root->subv_writers);
3519	free_extent_buffer(root->node);
3520	free_extent_buffer(root->commit_root);
3521	kfree(root->free_ino_ctl);
3522	kfree(root->free_ino_pinned);
3523	kfree(root->name);
3524	btrfs_put_fs_root(root);
3525}
3526
3527void btrfs_free_fs_root(struct btrfs_root *root)
3528{
3529	free_fs_root(root);
3530}
3531
3532int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
3533{
3534	u64 root_objectid = 0;
3535	struct btrfs_root *gang[8];
3536	int i;
3537	int ret;
 
 
3538
3539	while (1) {
 
3540		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
3541					     (void **)gang, root_objectid,
3542					     ARRAY_SIZE(gang));
3543		if (!ret)
 
3544			break;
 
 
3545
3546		root_objectid = gang[ret - 1]->root_key.objectid + 1;
3547		for (i = 0; i < ret; i++) {
3548			int err;
 
 
 
 
 
 
 
 
3549
 
 
 
3550			root_objectid = gang[i]->root_key.objectid;
3551			err = btrfs_orphan_cleanup(gang[i]);
3552			if (err)
3553				return err;
 
3554		}
3555		root_objectid++;
3556	}
3557	return 0;
 
 
 
 
 
 
3558}
3559
3560int btrfs_commit_super(struct btrfs_root *root)
3561{
 
3562	struct btrfs_trans_handle *trans;
3563
3564	mutex_lock(&root->fs_info->cleaner_mutex);
3565	btrfs_run_delayed_iputs(root);
3566	mutex_unlock(&root->fs_info->cleaner_mutex);
3567	wake_up_process(root->fs_info->cleaner_kthread);
3568
3569	/* wait until ongoing cleanup work done */
3570	down_write(&root->fs_info->cleanup_work_sem);
3571	up_write(&root->fs_info->cleanup_work_sem);
3572
3573	trans = btrfs_join_transaction(root);
3574	if (IS_ERR(trans))
3575		return PTR_ERR(trans);
3576	return btrfs_commit_transaction(trans, root);
3577}
3578
3579int close_ctree(struct btrfs_root *root)
3580{
3581	struct btrfs_fs_info *fs_info = root->fs_info;
3582	int ret;
3583
3584	fs_info->closing = 1;
3585	smp_mb();
 
 
 
 
 
 
 
 
 
3586
3587	/* wait for the uuid_scan task to finish */
3588	down(&fs_info->uuid_tree_rescan_sem);
3589	/* avoid complains from lockdep et al., set sem back to initial state */
3590	up(&fs_info->uuid_tree_rescan_sem);
3591
3592	/* pause restriper - we want to resume on mount */
3593	btrfs_pause_balance(fs_info);
3594
3595	btrfs_dev_replace_suspend_for_unmount(fs_info);
3596
3597	btrfs_scrub_cancel(fs_info);
3598
3599	/* wait for any defraggers to finish */
3600	wait_event(fs_info->transaction_wait,
3601		   (atomic_read(&fs_info->defrag_running) == 0));
3602
3603	/* clear out the rbtree of defraggable inodes */
3604	btrfs_cleanup_defrag_inodes(fs_info);
3605
3606	if (!(fs_info->sb->s_flags & MS_RDONLY)) {
3607		ret = btrfs_commit_super(root);
 
 
 
 
 
 
 
 
3608		if (ret)
3609			btrfs_err(root->fs_info, "commit super ret %d", ret);
3610	}
3611
3612	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
3613		btrfs_error_commit_super(root);
 
3614
3615	kthread_stop(fs_info->transaction_kthread);
3616	kthread_stop(fs_info->cleaner_kthread);
3617
3618	fs_info->closing = 2;
3619	smp_mb();
3620
3621	btrfs_free_qgroup_config(root->fs_info);
 
3622
3623	if (percpu_counter_sum(&fs_info->delalloc_bytes)) {
3624		btrfs_info(root->fs_info, "at unmount delalloc count %lld",
3625		       percpu_counter_sum(&fs_info->delalloc_bytes));
3626	}
3627
3628	btrfs_sysfs_remove_one(fs_info);
 
 
 
 
 
3629
3630	del_fs_roots(fs_info);
3631
3632	btrfs_put_block_group_cache(fs_info);
3633
 
 
 
 
 
 
 
3634	btrfs_free_block_groups(fs_info);
3635
3636	btrfs_stop_all_workers(fs_info);
3637
3638	free_root_pointers(fs_info, 1);
3639
3640	iput(fs_info->btree_inode);
3641
3642#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3643	if (btrfs_test_opt(root, CHECK_INTEGRITY))
3644		btrfsic_unmount(root, fs_info->fs_devices);
3645#endif
3646
 
3647	btrfs_close_devices(fs_info->fs_devices);
3648	btrfs_mapping_tree_free(&fs_info->mapping_tree);
3649
3650	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
3651	percpu_counter_destroy(&fs_info->delalloc_bytes);
3652	percpu_counter_destroy(&fs_info->bio_counter);
3653	bdi_destroy(&fs_info->bdi);
3654	cleanup_srcu_struct(&fs_info->subvol_srcu);
3655
 
3656	btrfs_free_stripe_hash_table(fs_info);
3657
3658	btrfs_free_block_rsv(root, root->orphan_block_rsv);
3659	root->orphan_block_rsv = NULL;
3660
3661	return 0;
3662}
3663
3664int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
3665			  int atomic)
3666{
3667	int ret;
3668	struct inode *btree_inode = buf->pages[0]->mapping->host;
3669
3670	ret = extent_buffer_uptodate(buf);
3671	if (!ret)
3672		return ret;
3673
3674	ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
3675				    parent_transid, atomic);
3676	if (ret == -EAGAIN)
3677		return ret;
3678	return !ret;
3679}
3680
3681int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
3682{
3683	return set_extent_buffer_uptodate(buf);
3684}
3685
3686void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
3687{
 
3688	struct btrfs_root *root;
3689	u64 transid = btrfs_header_generation(buf);
3690	int was_dirty;
3691
3692#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
3693	/*
3694	 * This is a fast path so only do this check if we have sanity tests
3695	 * enabled.  Normal people shouldn't be marking dummy buffers as dirty
3696	 * outside of the sanity tests.
3697	 */
3698	if (unlikely(test_bit(EXTENT_BUFFER_DUMMY, &buf->bflags)))
3699		return;
3700#endif
3701	root = BTRFS_I(buf->pages[0]->mapping->host)->root;
 
3702	btrfs_assert_tree_locked(buf);
3703	if (transid != root->fs_info->generation)
3704		WARN(1, KERN_CRIT "btrfs transid mismatch buffer %llu, "
3705		       "found %llu running %llu\n",
3706			buf->start, transid, root->fs_info->generation);
3707	was_dirty = set_extent_buffer_dirty(buf);
3708	if (!was_dirty)
3709		__percpu_counter_add(&root->fs_info->dirty_metadata_bytes,
3710				     buf->len,
3711				     root->fs_info->dirty_metadata_batch);
 
 
 
 
 
 
 
 
 
 
 
 
3712}
3713
3714static void __btrfs_btree_balance_dirty(struct btrfs_root *root,
3715					int flush_delayed)
3716{
3717	/*
3718	 * looks as though older kernels can get into trouble with
3719	 * this code, they end up stuck in balance_dirty_pages forever
3720	 */
3721	int ret;
3722
3723	if (current->flags & PF_MEMALLOC)
3724		return;
3725
3726	if (flush_delayed)
3727		btrfs_balance_delayed_items(root);
3728
3729	ret = percpu_counter_compare(&root->fs_info->dirty_metadata_bytes,
3730				     BTRFS_DIRTY_METADATA_THRESH);
 
3731	if (ret > 0) {
3732		balance_dirty_pages_ratelimited(
3733				   root->fs_info->btree_inode->i_mapping);
3734	}
3735	return;
3736}
3737
3738void btrfs_btree_balance_dirty(struct btrfs_root *root)
3739{
3740	__btrfs_btree_balance_dirty(root, 1);
3741}
3742
3743void btrfs_btree_balance_dirty_nodelay(struct btrfs_root *root)
3744{
3745	__btrfs_btree_balance_dirty(root, 0);
3746}
3747
3748int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
3749{
3750	struct btrfs_root *root = BTRFS_I(buf->pages[0]->mapping->host)->root;
3751	return btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
3752}
3753
3754static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
3755			      int read_only)
3756{
3757	/*
3758	 * Placeholder for checks
3759	 */
3760	return 0;
3761}
3762
3763static void btrfs_error_commit_super(struct btrfs_root *root)
3764{
3765	mutex_lock(&root->fs_info->cleaner_mutex);
3766	btrfs_run_delayed_iputs(root);
3767	mutex_unlock(&root->fs_info->cleaner_mutex);
3768
3769	down_write(&root->fs_info->cleanup_work_sem);
3770	up_write(&root->fs_info->cleanup_work_sem);
3771
3772	/* cleanup FS via transaction */
3773	btrfs_cleanup_transaction(root);
3774}
3775
3776static void btrfs_destroy_ordered_operations(struct btrfs_transaction *t,
3777					     struct btrfs_root *root)
3778{
3779	struct btrfs_inode *btrfs_inode;
3780	struct list_head splice;
3781
3782	INIT_LIST_HEAD(&splice);
3783
3784	mutex_lock(&root->fs_info->ordered_operations_mutex);
3785	spin_lock(&root->fs_info->ordered_root_lock);
3786
3787	list_splice_init(&t->ordered_operations, &splice);
3788	while (!list_empty(&splice)) {
3789		btrfs_inode = list_entry(splice.next, struct btrfs_inode,
3790					 ordered_operations);
3791
3792		list_del_init(&btrfs_inode->ordered_operations);
3793		spin_unlock(&root->fs_info->ordered_root_lock);
3794
3795		btrfs_invalidate_inodes(btrfs_inode->root);
3796
3797		spin_lock(&root->fs_info->ordered_root_lock);
3798	}
3799
3800	spin_unlock(&root->fs_info->ordered_root_lock);
3801	mutex_unlock(&root->fs_info->ordered_operations_mutex);
3802}
3803
3804static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
3805{
3806	struct btrfs_ordered_extent *ordered;
3807
3808	spin_lock(&root->ordered_extent_lock);
3809	/*
3810	 * This will just short circuit the ordered completion stuff which will
3811	 * make sure the ordered extent gets properly cleaned up.
3812	 */
3813	list_for_each_entry(ordered, &root->ordered_extents,
3814			    root_extent_list)
3815		set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
3816	spin_unlock(&root->ordered_extent_lock);
3817}
3818
3819static void btrfs_destroy_all_ordered_extents(struct btrfs_fs_info *fs_info)
3820{
3821	struct btrfs_root *root;
3822	struct list_head splice;
3823
3824	INIT_LIST_HEAD(&splice);
3825
3826	spin_lock(&fs_info->ordered_root_lock);
3827	list_splice_init(&fs_info->ordered_roots, &splice);
3828	while (!list_empty(&splice)) {
3829		root = list_first_entry(&splice, struct btrfs_root,
3830					ordered_root);
3831		list_move_tail(&root->ordered_root,
3832			       &fs_info->ordered_roots);
3833
3834		spin_unlock(&fs_info->ordered_root_lock);
3835		btrfs_destroy_ordered_extents(root);
3836
3837		cond_resched();
3838		spin_lock(&fs_info->ordered_root_lock);
3839	}
3840	spin_unlock(&fs_info->ordered_root_lock);
 
 
 
 
 
 
 
 
3841}
3842
3843static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
3844				      struct btrfs_root *root)
3845{
3846	struct rb_node *node;
3847	struct btrfs_delayed_ref_root *delayed_refs;
3848	struct btrfs_delayed_ref_node *ref;
3849	int ret = 0;
3850
3851	delayed_refs = &trans->delayed_refs;
3852
3853	spin_lock(&delayed_refs->lock);
3854	if (atomic_read(&delayed_refs->num_entries) == 0) {
3855		spin_unlock(&delayed_refs->lock);
3856		btrfs_info(root->fs_info, "delayed_refs has NO entry");
3857		return ret;
3858	}
3859
3860	while ((node = rb_first(&delayed_refs->href_root)) != NULL) {
3861		struct btrfs_delayed_ref_head *head;
 
3862		bool pin_bytes = false;
3863
3864		head = rb_entry(node, struct btrfs_delayed_ref_head,
3865				href_node);
3866		if (!mutex_trylock(&head->mutex)) {
3867			atomic_inc(&head->node.refs);
3868			spin_unlock(&delayed_refs->lock);
3869
3870			mutex_lock(&head->mutex);
3871			mutex_unlock(&head->mutex);
3872			btrfs_put_delayed_ref(&head->node);
3873			spin_lock(&delayed_refs->lock);
3874			continue;
3875		}
3876		spin_lock(&head->lock);
3877		while ((node = rb_first(&head->ref_root)) != NULL) {
3878			ref = rb_entry(node, struct btrfs_delayed_ref_node,
3879				       rb_node);
3880			ref->in_tree = 0;
3881			rb_erase(&ref->rb_node, &head->ref_root);
 
 
 
3882			atomic_dec(&delayed_refs->num_entries);
3883			btrfs_put_delayed_ref(ref);
3884		}
3885		if (head->must_insert_reserved)
3886			pin_bytes = true;
3887		btrfs_free_delayed_extent_op(head->extent_op);
3888		delayed_refs->num_heads--;
3889		if (head->processing == 0)
3890			delayed_refs->num_heads_ready--;
3891		atomic_dec(&delayed_refs->num_entries);
3892		head->node.in_tree = 0;
3893		rb_erase(&head->href_node, &delayed_refs->href_root);
3894		spin_unlock(&head->lock);
3895		spin_unlock(&delayed_refs->lock);
3896		mutex_unlock(&head->mutex);
3897
3898		if (pin_bytes)
3899			btrfs_pin_extent(root, head->node.bytenr,
3900					 head->node.num_bytes, 1);
3901		btrfs_put_delayed_ref(&head->node);
 
3902		cond_resched();
3903		spin_lock(&delayed_refs->lock);
3904	}
3905
3906	spin_unlock(&delayed_refs->lock);
3907
3908	return ret;
3909}
3910
3911static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
3912{
3913	struct btrfs_inode *btrfs_inode;
3914	struct list_head splice;
3915
3916	INIT_LIST_HEAD(&splice);
3917
3918	spin_lock(&root->delalloc_lock);
3919	list_splice_init(&root->delalloc_inodes, &splice);
3920
3921	while (!list_empty(&splice)) {
 
3922		btrfs_inode = list_first_entry(&splice, struct btrfs_inode,
3923					       delalloc_inodes);
3924
3925		list_del_init(&btrfs_inode->delalloc_inodes);
3926		clear_bit(BTRFS_INODE_IN_DELALLOC_LIST,
3927			  &btrfs_inode->runtime_flags);
3928		spin_unlock(&root->delalloc_lock);
3929
3930		btrfs_invalidate_inodes(btrfs_inode->root);
3931
 
 
 
 
 
 
 
3932		spin_lock(&root->delalloc_lock);
3933	}
3934
3935	spin_unlock(&root->delalloc_lock);
3936}
3937
3938static void btrfs_destroy_all_delalloc_inodes(struct btrfs_fs_info *fs_info)
3939{
3940	struct btrfs_root *root;
3941	struct list_head splice;
3942
3943	INIT_LIST_HEAD(&splice);
3944
3945	spin_lock(&fs_info->delalloc_root_lock);
3946	list_splice_init(&fs_info->delalloc_roots, &splice);
3947	while (!list_empty(&splice)) {
3948		root = list_first_entry(&splice, struct btrfs_root,
3949					 delalloc_root);
3950		list_del_init(&root->delalloc_root);
3951		root = btrfs_grab_fs_root(root);
3952		BUG_ON(!root);
3953		spin_unlock(&fs_info->delalloc_root_lock);
3954
3955		btrfs_destroy_delalloc_inodes(root);
3956		btrfs_put_fs_root(root);
3957
3958		spin_lock(&fs_info->delalloc_root_lock);
3959	}
3960	spin_unlock(&fs_info->delalloc_root_lock);
3961}
3962
3963static int btrfs_destroy_marked_extents(struct btrfs_root *root,
3964					struct extent_io_tree *dirty_pages,
3965					int mark)
3966{
3967	int ret;
3968	struct extent_buffer *eb;
3969	u64 start = 0;
3970	u64 end;
3971
3972	while (1) {
3973		ret = find_first_extent_bit(dirty_pages, start, &start, &end,
3974					    mark, NULL);
3975		if (ret)
3976			break;
3977
3978		clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS);
3979		while (start <= end) {
3980			eb = btrfs_find_tree_block(root, start,
3981						   root->leafsize);
3982			start += root->leafsize;
3983			if (!eb)
3984				continue;
3985			wait_on_extent_buffer_writeback(eb);
3986
3987			if (test_and_clear_bit(EXTENT_BUFFER_DIRTY,
3988					       &eb->bflags))
3989				clear_extent_buffer_dirty(eb);
3990			free_extent_buffer_stale(eb);
3991		}
3992	}
3993
3994	return ret;
3995}
3996
3997static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
3998				       struct extent_io_tree *pinned_extents)
3999{
4000	struct extent_io_tree *unpin;
4001	u64 start;
4002	u64 end;
4003	int ret;
4004	bool loop = true;
4005
4006	unpin = pinned_extents;
4007again:
4008	while (1) {
 
 
 
 
 
 
 
 
 
4009		ret = find_first_extent_bit(unpin, 0, &start, &end,
4010					    EXTENT_DIRTY, NULL);
4011		if (ret)
 
4012			break;
 
4013
4014		/* opt_discard */
4015		if (btrfs_test_opt(root, DISCARD))
4016			ret = btrfs_error_discard_extent(root, start,
4017							 end + 1 - start,
4018							 NULL);
4019
4020		clear_extent_dirty(unpin, start, end, GFP_NOFS);
4021		btrfs_error_unpin_extent_range(root, start, end);
4022		cond_resched();
4023	}
4024
4025	if (loop) {
4026		if (unpin == &root->fs_info->freed_extents[0])
4027			unpin = &root->fs_info->freed_extents[1];
4028		else
4029			unpin = &root->fs_info->freed_extents[0];
4030		loop = false;
4031		goto again;
4032	}
4033
4034	return 0;
4035}
4036
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4037void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
4038				   struct btrfs_root *root)
4039{
4040	btrfs_destroy_ordered_operations(cur_trans, root);
4041
4042	btrfs_destroy_delayed_refs(cur_trans, root);
 
 
 
 
 
 
 
 
 
4043
4044	cur_trans->state = TRANS_STATE_COMMIT_START;
4045	wake_up(&root->fs_info->transaction_blocked_wait);
4046
4047	cur_trans->state = TRANS_STATE_UNBLOCKED;
4048	wake_up(&root->fs_info->transaction_wait);
4049
4050	btrfs_destroy_delayed_inodes(root);
4051	btrfs_assert_delayed_root_empty(root);
4052
4053	btrfs_destroy_marked_extents(root, &cur_trans->dirty_pages,
4054				     EXTENT_DIRTY);
4055	btrfs_destroy_pinned_extent(root,
4056				    root->fs_info->pinned_extents);
4057
4058	cur_trans->state =TRANS_STATE_COMPLETED;
4059	wake_up(&cur_trans->commit_wait);
4060
4061	/*
4062	memset(cur_trans, 0, sizeof(*cur_trans));
4063	kmem_cache_free(btrfs_transaction_cachep, cur_trans);
4064	*/
4065}
4066
4067static int btrfs_cleanup_transaction(struct btrfs_root *root)
4068{
4069	struct btrfs_transaction *t;
4070
4071	mutex_lock(&root->fs_info->transaction_kthread_mutex);
4072
4073	spin_lock(&root->fs_info->trans_lock);
4074	while (!list_empty(&root->fs_info->trans_list)) {
4075		t = list_first_entry(&root->fs_info->trans_list,
4076				     struct btrfs_transaction, list);
4077		if (t->state >= TRANS_STATE_COMMIT_START) {
4078			atomic_inc(&t->use_count);
4079			spin_unlock(&root->fs_info->trans_lock);
4080			btrfs_wait_for_commit(root, t->transid);
4081			btrfs_put_transaction(t);
4082			spin_lock(&root->fs_info->trans_lock);
4083			continue;
4084		}
4085		if (t == root->fs_info->running_transaction) {
4086			t->state = TRANS_STATE_COMMIT_DOING;
4087			spin_unlock(&root->fs_info->trans_lock);
4088			/*
4089			 * We wait for 0 num_writers since we don't hold a trans
4090			 * handle open currently for this transaction.
4091			 */
4092			wait_event(t->writer_wait,
4093				   atomic_read(&t->num_writers) == 0);
4094		} else {
4095			spin_unlock(&root->fs_info->trans_lock);
4096		}
4097		btrfs_cleanup_one_transaction(t, root);
4098
4099		spin_lock(&root->fs_info->trans_lock);
4100		if (t == root->fs_info->running_transaction)
4101			root->fs_info->running_transaction = NULL;
4102		list_del_init(&t->list);
4103		spin_unlock(&root->fs_info->trans_lock);
4104
4105		btrfs_put_transaction(t);
4106		trace_btrfs_transaction_commit(root);
4107		spin_lock(&root->fs_info->trans_lock);
4108	}
4109	spin_unlock(&root->fs_info->trans_lock);
4110	btrfs_destroy_all_ordered_extents(root->fs_info);
4111	btrfs_destroy_delayed_inodes(root);
4112	btrfs_assert_delayed_root_empty(root);
4113	btrfs_destroy_pinned_extent(root, root->fs_info->pinned_extents);
4114	btrfs_destroy_all_delalloc_inodes(root->fs_info);
4115	mutex_unlock(&root->fs_info->transaction_kthread_mutex);
4116
4117	return 0;
4118}
4119
4120static struct extent_io_ops btree_extent_io_ops = {
 
 
4121	.readpage_end_io_hook = btree_readpage_end_io_hook,
4122	.readpage_io_failed_hook = btree_io_failed_hook,
4123	.submit_bio_hook = btree_submit_bio_hook,
4124	/* note we're sharing with inode.c for the merge bio hook */
4125	.merge_bio_hook = btrfs_merge_bio_hook,
4126};