Moved, renamed, and deleted files

The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.

1 files changed, 0 insertions, 3693 deletions

diff --git a/ANDROID_3.4.5/fs/btrfs/disk-io.c b/ANDROID_3.4.5/fs/btrfs/disk-io.c
deleted file mode 100644
index a7ffc88a..00000000
--- a/ANDROID_3.4.5/fs/btrfs/disk-io.c
+++ /dev/null
@@ -1,3693 +0,0 @@
-/*
- * Copyright (C) 2007 Oracle.  All rights reserved.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public
- * License v2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public
- * License along with this program; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 021110-1307, USA.
- */
-
-#include <linux/fs.h>
-#include <linux/blkdev.h>
-#include <linux/scatterlist.h>
-#include <linux/swap.h>
-#include <linux/radix-tree.h>
-#include <linux/writeback.h>
-#include <linux/buffer_head.h>
-#include <linux/workqueue.h>
-#include <linux/kthread.h>
-#include <linux/freezer.h>
-#include <linux/crc32c.h>
-#include <linux/slab.h>
-#include <linux/migrate.h>
-#include <linux/ratelimit.h>
-#include <asm/unaligned.h>
-#include "compat.h"
-#include "ctree.h"
-#include "disk-io.h"
-#include "transaction.h"
-#include "btrfs_inode.h"
-#include "volumes.h"
-#include "print-tree.h"
-#include "async-thread.h"
-#include "locking.h"
-#include "tree-log.h"
-#include "free-space-cache.h"
-#include "inode-map.h"
-#include "check-integrity.h"
-
-static struct extent_io_ops btree_extent_io_ops;
-static void end_workqueue_fn(struct btrfs_work *work);
-static void free_fs_root(struct btrfs_root *root);
-static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
-				    int read_only);
-static void btrfs_destroy_ordered_operations(struct btrfs_root *root);
-static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
-static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
-				      struct btrfs_root *root);
-static void btrfs_destroy_pending_snapshots(struct btrfs_transaction *t);
-static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
-static int btrfs_destroy_marked_extents(struct btrfs_root *root,
-					struct extent_io_tree *dirty_pages,
-					int mark);
-static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
-				       struct extent_io_tree *pinned_extents);
-
-/*
- * end_io_wq structs are used to do processing in task context when an IO is
- * complete.  This is used during reads to verify checksums, and it is used
- * by writes to insert metadata for new file extents after IO is complete.
- */
-struct end_io_wq {
-	struct bio *bio;
-	bio_end_io_t *end_io;
-	void *private;
-	struct btrfs_fs_info *info;
-	int error;
-	int metadata;
-	struct list_head list;
-	struct btrfs_work work;
-};
-
-/*
- * async submit bios are used to offload expensive checksumming
- * onto the worker threads.  They checksum file and metadata bios
- * just before they are sent down the IO stack.
- */
-struct async_submit_bio {
-	struct inode *inode;
-	struct bio *bio;
-	struct list_head list;
-	extent_submit_bio_hook_t *submit_bio_start;
-	extent_submit_bio_hook_t *submit_bio_done;
-	int rw;
-	int mirror_num;
-	unsigned long bio_flags;
-	/*
-	 * bio_offset is optional, can be used if the pages in the bio
-	 * can't tell us where in the file the bio should go
-	 */
-	u64 bio_offset;
-	struct btrfs_work work;
-	int error;
-};
-
-/*
- * Lockdep class keys for extent_buffer->lock's in this root.  For a given
- * eb, the lockdep key is determined by the btrfs_root it belongs to and
- * the level the eb occupies in the tree.
- *
- * Different roots are used for different purposes and may nest inside each
- * other and they require separate keysets.  As lockdep keys should be
- * static, assign keysets according to the purpose of the root as indicated
- * by btrfs_root->objectid.  This ensures that all special purpose roots
- * have separate keysets.
- *
- * Lock-nesting across peer nodes is always done with the immediate parent
- * node locked thus preventing deadlock.  As lockdep doesn't know this, use
- * subclass to avoid triggering lockdep warning in such cases.
- *
- * The key is set by the readpage_end_io_hook after the buffer has passed
- * csum validation but before the pages are unlocked.  It is also set by
- * btrfs_init_new_buffer on freshly allocated blocks.
- *
- * We also add a check to make sure the highest level of the tree is the
- * same as our lockdep setup here.  If BTRFS_MAX_LEVEL changes, this code
- * needs update as well.
- */
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# if BTRFS_MAX_LEVEL != 8
-#  error
-# endif
-
-static struct btrfs_lockdep_keyset {
-	u64			id;		/* root objectid */
-	const char		*name_stem;	/* lock name stem */
-	char			names[BTRFS_MAX_LEVEL + 1][20];
-	struct lock_class_key	keys[BTRFS_MAX_LEVEL + 1];
-} btrfs_lockdep_keysets[] = {
-	{ .id = BTRFS_ROOT_TREE_OBJECTID,	.name_stem = "root"	},
-	{ .id = BTRFS_EXTENT_TREE_OBJECTID,	.name_stem = "extent"	},
-	{ .id = BTRFS_CHUNK_TREE_OBJECTID,	.name_stem = "chunk"	},
-	{ .id = BTRFS_DEV_TREE_OBJECTID,	.name_stem = "dev"	},
-	{ .id = BTRFS_FS_TREE_OBJECTID,		.name_stem = "fs"	},
-	{ .id = BTRFS_CSUM_TREE_OBJECTID,	.name_stem = "csum"	},
-	{ .id = BTRFS_ORPHAN_OBJECTID,		.name_stem = "orphan"	},
-	{ .id = BTRFS_TREE_LOG_OBJECTID,	.name_stem = "log"	},
-	{ .id = BTRFS_TREE_RELOC_OBJECTID,	.name_stem = "treloc"	},
-	{ .id = BTRFS_DATA_RELOC_TREE_OBJECTID,	.name_stem = "dreloc"	},
-	{ .id = 0,				.name_stem = "tree"	},
-};
-
-void __init btrfs_init_lockdep(void)
-{
-	int i, j;
-
-	/* initialize lockdep class names */
-	for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) {
-		struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i];
-
-		for (j = 0; j < ARRAY_SIZE(ks->names); j++)
-			snprintf(ks->names[j], sizeof(ks->names[j]),
-				 "btrfs-%s-%02d", ks->name_stem, j);
-	}
-}
-
-void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
-				    int level)
-{
-	struct btrfs_lockdep_keyset *ks;
-
-	BUG_ON(level >= ARRAY_SIZE(ks->keys));
-
-	/* find the matching keyset, id 0 is the default entry */
-	for (ks = btrfs_lockdep_keysets; ks->id; ks++)
-		if (ks->id == objectid)
-			break;
-
-	lockdep_set_class_and_name(&eb->lock,
-				   &ks->keys[level], ks->names[level]);
-}
-
-#endif
-
-/*
- * extents on the btree inode are pretty simple, there's one extent
- * that covers the entire device
- */
-static struct extent_map *btree_get_extent(struct inode *inode,
-		struct page *page, size_t pg_offset, u64 start, u64 len,
-		int create)
-{
-	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
-	struct extent_map *em;
-	int ret;
-
-	read_lock(&em_tree->lock);
-	em = lookup_extent_mapping(em_tree, start, len);
-	if (em) {
-		em->bdev =
-			BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
-		read_unlock(&em_tree->lock);
-		goto out;
-	}
-	read_unlock(&em_tree->lock);
-
-	em = alloc_extent_map();
-	if (!em) {
-		em = ERR_PTR(-ENOMEM);
-		goto out;
-	}
-	em->start = 0;
-	em->len = (u64)-1;
-	em->block_len = (u64)-1;
-	em->block_start = 0;
-	em->bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
-
-	write_lock(&em_tree->lock);
-	ret = add_extent_mapping(em_tree, em);
-	if (ret == -EEXIST) {
-		u64 failed_start = em->start;
-		u64 failed_len = em->len;
-
-		free_extent_map(em);
-		em = lookup_extent_mapping(em_tree, start, len);
-		if (em) {
-			ret = 0;
-		} else {
-			em = lookup_extent_mapping(em_tree, failed_start,
-						   failed_len);
-			ret = -EIO;
-		}
-	} else if (ret) {
-		free_extent_map(em);
-		em = NULL;
-	}
-	write_unlock(&em_tree->lock);
-
-	if (ret)
-		em = ERR_PTR(ret);
-out:
-	return em;
-}
-
-u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
-{
-	return crc32c(seed, data, len);
-}
-
-void btrfs_csum_final(u32 crc, char *result)
-{
-	put_unaligned_le32(~crc, result);
-}
-
-/*
- * compute the csum for a btree block, and either verify it or write it
- * into the csum field of the block.
- */
-static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
-			   int verify)
-{
-	u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
-	char *result = NULL;
-	unsigned long len;
-	unsigned long cur_len;
-	unsigned long offset = BTRFS_CSUM_SIZE;
-	char *kaddr;
-	unsigned long map_start;
-	unsigned long map_len;
-	int err;
-	u32 crc = ~(u32)0;
-	unsigned long inline_result;
-
-	len = buf->len - offset;
-	while (len > 0) {
-		err = map_private_extent_buffer(buf, offset, 32,
-					&kaddr, &map_start, &map_len);
-		if (err)
-			return 1;
-		cur_len = min(len, map_len - (offset - map_start));
-		crc = btrfs_csum_data(root, kaddr + offset - map_start,
-				      crc, cur_len);
-		len -= cur_len;
-		offset += cur_len;
-	}
-	if (csum_size > sizeof(inline_result)) {
-		result = kzalloc(csum_size * sizeof(char), GFP_NOFS);
-		if (!result)
-			return 1;
-	} else {
-		result = (char *)&inline_result;
-	}
-
-	btrfs_csum_final(crc, result);
-
-	if (verify) {
-		if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
-			u32 val;
-			u32 found = 0;
-			memcpy(&found, result, csum_size);
-
-			read_extent_buffer(buf, &val, 0, csum_size);
-			printk_ratelimited(KERN_INFO "btrfs: %s checksum verify "
-				       "failed on %llu wanted %X found %X "
-				       "level %d\n",
-				       root->fs_info->sb->s_id,
-				       (unsigned long long)buf->start, val, found,
-				       btrfs_header_level(buf));
-			if (result != (char *)&inline_result)
-				kfree(result);
-			return 1;
-		}
-	} else {
-		write_extent_buffer(buf, result, 0, csum_size);
-	}
-	if (result != (char *)&inline_result)
-		kfree(result);
-	return 0;
-}
-
-/*
- * we can't consider a given block up to date unless the transid of the
- * block matches the transid in the parent node's pointer.  This is how we
- * detect blocks that either didn't get written at all or got written
- * in the wrong place.
- */
-static int verify_parent_transid(struct extent_io_tree *io_tree,
-				 struct extent_buffer *eb, u64 parent_transid,
-				 int atomic)
-{
-	struct extent_state *cached_state = NULL;
-	int ret;
-
-	if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
-		return 0;
-
-	if (atomic)
-		return -EAGAIN;
-
-	lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
-			 0, &cached_state);
-	if (extent_buffer_uptodate(eb) &&
-	    btrfs_header_generation(eb) == parent_transid) {
-		ret = 0;
-		goto out;
-	}
-	printk_ratelimited("parent transid verify failed on %llu wanted %llu "
-		       "found %llu\n",
-		       (unsigned long long)eb->start,
-		       (unsigned long long)parent_transid,
-		       (unsigned long long)btrfs_header_generation(eb));
-	ret = 1;
-	clear_extent_buffer_uptodate(eb);
-out:
-	unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
-			     &cached_state, GFP_NOFS);
-	return ret;
-}
-
-/*
- * helper to read a given tree block, doing retries as required when
- * the checksums don't match and we have alternate mirrors to try.
- */
-static int btree_read_extent_buffer_pages(struct btrfs_root *root,
-					  struct extent_buffer *eb,
-					  u64 start, u64 parent_transid)
-{
-	struct extent_io_tree *io_tree;
-	int failed = 0;
-	int ret;
-	int num_copies = 0;
-	int mirror_num = 0;
-	int failed_mirror = 0;
-
-	clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
-	io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
-	while (1) {
-		ret = read_extent_buffer_pages(io_tree, eb, start,
-					       WAIT_COMPLETE,
-					       btree_get_extent, mirror_num);
-		if (!ret && !verify_parent_transid(io_tree, eb,
-						   parent_transid, 0))
-			break;
-
-		/*
-		 * This buffer's crc is fine, but its contents are corrupted, so
-		 * there is no reason to read the other copies, they won't be
-		 * any less wrong.
-		 */
-		if (test_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags))
-			break;
-
-		num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
-					      eb->start, eb->len);
-		if (num_copies == 1)
-			break;
-
-		if (!failed_mirror) {
-			failed = 1;
-			failed_mirror = eb->read_mirror;
-		}
-
-		mirror_num++;
-		if (mirror_num == failed_mirror)
-			mirror_num++;
-
-		if (mirror_num > num_copies)
-			break;
-	}
-
-	if (failed && !ret)
-		repair_eb_io_failure(root, eb, failed_mirror);
-
-	return ret;
-}
-
-/*
- * checksum a dirty tree block before IO.  This has extra checks to make sure
- * we only fill in the checksum field in the first page of a multi-page block
- */
-
-static int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
-{
-	struct extent_io_tree *tree;
-	u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
-	u64 found_start;
-	struct extent_buffer *eb;
-
-	tree = &BTRFS_I(page->mapping->host)->io_tree;
-
-	eb = (struct extent_buffer *)page->private;
-	if (page != eb->pages[0])
-		return 0;
-	found_start = btrfs_header_bytenr(eb);
-	if (found_start != start) {
-		WARN_ON(1);
-		return 0;
-	}
-	if (eb->pages[0] != page) {
-		WARN_ON(1);
-		return 0;
-	}
-	if (!PageUptodate(page)) {
-		WARN_ON(1);
-		return 0;
-	}
-	csum_tree_block(root, eb, 0);
-	return 0;
-}
-
-static int check_tree_block_fsid(struct btrfs_root *root,
-				 struct extent_buffer *eb)
-{
-	struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
-	u8 fsid[BTRFS_UUID_SIZE];
-	int ret = 1;
-
-	read_extent_buffer(eb, fsid, (unsigned long)btrfs_header_fsid(eb),
-			   BTRFS_FSID_SIZE);
-	while (fs_devices) {
-		if (!memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE)) {
-			ret = 0;
-			break;
-		}
-		fs_devices = fs_devices->seed;
-	}
-	return ret;
-}
-
-#define CORRUPT(reason, eb, root, slot)				\
-	printk(KERN_CRIT "btrfs: corrupt leaf, %s: block=%llu,"	\
-	       "root=%llu, slot=%d\n", reason,			\
-	       (unsigned long long)btrfs_header_bytenr(eb),	\
-	       (unsigned long long)root->objectid, slot)
-
-static noinline int check_leaf(struct btrfs_root *root,
-			       struct extent_buffer *leaf)
-{
-	struct btrfs_key key;
-	struct btrfs_key leaf_key;
-	u32 nritems = btrfs_header_nritems(leaf);
-	int slot;
-
-	if (nritems == 0)
-		return 0;
-
-	/* Check the 0 item */
-	if (btrfs_item_offset_nr(leaf, 0) + btrfs_item_size_nr(leaf, 0) !=
-	    BTRFS_LEAF_DATA_SIZE(root)) {
-		CORRUPT("invalid item offset size pair", leaf, root, 0);
-		return -EIO;
-	}
-
-	/*
-	 * Check to make sure each items keys are in the correct order and their
-	 * offsets make sense.  We only have to loop through nritems-1 because
-	 * we check the current slot against the next slot, which verifies the
-	 * next slot's offset+size makes sense and that the current's slot
-	 * offset is correct.
-	 */
-	for (slot = 0; slot < nritems - 1; slot++) {
-		btrfs_item_key_to_cpu(leaf, &leaf_key, slot);
-		btrfs_item_key_to_cpu(leaf, &key, slot + 1);
-
-		/* Make sure the keys are in the right order */
-		if (btrfs_comp_cpu_keys(&leaf_key, &key) >= 0) {
-			CORRUPT("bad key order", leaf, root, slot);
-			return -EIO;
-		}
-
-		/*
-		 * Make sure the offset and ends are right, remember that the
-		 * item data starts at the end of the leaf and grows towards the
-		 * front.
-		 */
-		if (btrfs_item_offset_nr(leaf, slot) !=
-			btrfs_item_end_nr(leaf, slot + 1)) {
-			CORRUPT("slot offset bad", leaf, root, slot);
-			return -EIO;
-		}
-
-		/*
-		 * Check to make sure that we don't point outside of the leaf,
-		 * just incase all the items are consistent to eachother, but
-		 * all point outside of the leaf.
-		 */
-		if (btrfs_item_end_nr(leaf, slot) >
-		    BTRFS_LEAF_DATA_SIZE(root)) {
-			CORRUPT("slot end outside of leaf", leaf, root, slot);
-			return -EIO;
-		}
-	}
-
-	return 0;
-}
-
-struct extent_buffer *find_eb_for_page(struct extent_io_tree *tree,
-				       struct page *page, int max_walk)
-{
-	struct extent_buffer *eb;
-	u64 start = page_offset(page);
-	u64 target = start;
-	u64 min_start;
-
-	if (start < max_walk)
-		min_start = 0;
-	else
-		min_start = start - max_walk;
-
-	while (start >= min_start) {
-		eb = find_extent_buffer(tree, start, 0);
-		if (eb) {
-			/*
-			 * we found an extent buffer and it contains our page
-			 * horray!
-			 */
-			if (eb->start <= target &&
-			    eb->start + eb->len > target)
-				return eb;
-
-			/* we found an extent buffer that wasn't for us */
-			free_extent_buffer(eb);
-			return NULL;
-		}
-		if (start == 0)
-			break;
-		start -= PAGE_CACHE_SIZE;
-	}
-	return NULL;
-}
-
-static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
-			       struct extent_state *state, int mirror)
-{
-	struct extent_io_tree *tree;
-	u64 found_start;
-	int found_level;
-	struct extent_buffer *eb;
-	struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
-	int ret = 0;
-	int reads_done;
-
-	if (!page->private)
-		goto out;
-
-	tree = &BTRFS_I(page->mapping->host)->io_tree;
-	eb = (struct extent_buffer *)page->private;
-
-	/* the pending IO might have been the only thing that kept this buffer
-	 * in memory.  Make sure we have a ref for all this other checks
-	 */
-	extent_buffer_get(eb);
-
-	reads_done = atomic_dec_and_test(&eb->io_pages);
-	if (!reads_done)
-		goto err;
-
-	eb->read_mirror = mirror;
-	if (test_bit(EXTENT_BUFFER_IOERR, &eb->bflags)) {
-		ret = -EIO;
-		goto err;
-	}
-
-	found_start = btrfs_header_bytenr(eb);
-	if (found_start != eb->start) {
-		printk_ratelimited(KERN_INFO "btrfs bad tree block start "
-			       "%llu %llu\n",
-			       (unsigned long long)found_start,
-			       (unsigned long long)eb->start);
-		ret = -EIO;
-		goto err;
-	}
-	if (check_tree_block_fsid(root, eb)) {
-		printk_ratelimited(KERN_INFO "btrfs bad fsid on block %llu\n",
-			       (unsigned long long)eb->start);
-		ret = -EIO;
-		goto err;
-	}
-	found_level = btrfs_header_level(eb);
-
-	btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb),
-				       eb, found_level);
-
-	ret = csum_tree_block(root, eb, 1);
-	if (ret) {
-		ret = -EIO;
-		goto err;
-	}
-
-	/*
-	 * If this is a leaf block and it is corrupt, set the corrupt bit so
-	 * that we don't try and read the other copies of this block, just
-	 * return -EIO.
-	 */
-	if (found_level == 0 && check_leaf(root, eb)) {
-		set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
-		ret = -EIO;
-	}
-
-	if (!ret)
-		set_extent_buffer_uptodate(eb);
-err:
-	if (test_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) {
-		clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags);
-		btree_readahead_hook(root, eb, eb->start, ret);
-	}
-
-	if (ret)
-		clear_extent_buffer_uptodate(eb);
-	free_extent_buffer(eb);
-out:
-	return ret;
-}
-
-static int btree_io_failed_hook(struct page *page, int failed_mirror)
-{
-	struct extent_buffer *eb;
-	struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
-
-	eb = (struct extent_buffer *)page->private;
-	set_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
-	eb->read_mirror = failed_mirror;
-	if (test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
-		btree_readahead_hook(root, eb, eb->start, -EIO);
-	return -EIO;	/* we fixed nothing */
-}
-
-static void end_workqueue_bio(struct bio *bio, int err)
-{
-	struct end_io_wq *end_io_wq = bio->bi_private;
-	struct btrfs_fs_info *fs_info;
-
-	fs_info = end_io_wq->info;
-	end_io_wq->error = err;
-	end_io_wq->work.func = end_workqueue_fn;
-	end_io_wq->work.flags = 0;
-
-	if (bio->bi_rw & REQ_WRITE) {
-		if (end_io_wq->metadata == 1)
-			btrfs_queue_worker(&fs_info->endio_meta_write_workers,
-					   &end_io_wq->work);
-		else if (end_io_wq->metadata == 2)
-			btrfs_queue_worker(&fs_info->endio_freespace_worker,
-					   &end_io_wq->work);
-		else
-			btrfs_queue_worker(&fs_info->endio_write_workers,
-					   &end_io_wq->work);
-	} else {
-		if (end_io_wq->metadata)
-			btrfs_queue_worker(&fs_info->endio_meta_workers,
-					   &end_io_wq->work);
-		else
-			btrfs_queue_worker(&fs_info->endio_workers,
-					   &end_io_wq->work);
-	}
-}
-
-/*
- * For the metadata arg you want
- *
- * 0 - if data
- * 1 - if normal metadta
- * 2 - if writing to the free space cache area
- */
-int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
-			int metadata)
-{
-	struct end_io_wq *end_io_wq;
-	end_io_wq = kmalloc(sizeof(*end_io_wq), GFP_NOFS);
-	if (!end_io_wq)
-		return -ENOMEM;
-
-	end_io_wq->private = bio->bi_private;
-	end_io_wq->end_io = bio->bi_end_io;
-	end_io_wq->info = info;
-	end_io_wq->error = 0;
-	end_io_wq->bio = bio;
-	end_io_wq->metadata = metadata;
-
-	bio->bi_private = end_io_wq;
-	bio->bi_end_io = end_workqueue_bio;
-	return 0;
-}
-
-unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info)
-{
-	unsigned long limit = min_t(unsigned long,
-				    info->workers.max_workers,
-				    info->fs_devices->open_devices);
-	return 256 * limit;
-}
-
-static void run_one_async_start(struct btrfs_work *work)
-{
-	struct async_submit_bio *async;
-	int ret;
-
-	async = container_of(work, struct  async_submit_bio, work);
-	ret = async->submit_bio_start(async->inode, async->rw, async->bio,
-				      async->mirror_num, async->bio_flags,
-				      async->bio_offset);
-	if (ret)
-		async->error = ret;
-}
-
-static void run_one_async_done(struct btrfs_work *work)
-{
-	struct btrfs_fs_info *fs_info;
-	struct async_submit_bio *async;
-	int limit;
-
-	async = container_of(work, struct  async_submit_bio, work);
-	fs_info = BTRFS_I(async->inode)->root->fs_info;
-
-	limit = btrfs_async_submit_limit(fs_info);
-	limit = limit * 2 / 3;
-
-	atomic_dec(&fs_info->nr_async_submits);
-
-	if (atomic_read(&fs_info->nr_async_submits) < limit &&
-	    waitqueue_active(&fs_info->async_submit_wait))
-		wake_up(&fs_info->async_submit_wait);
-
-	/* If an error occured we just want to clean up the bio and move on */
-	if (async->error) {
-		bio_endio(async->bio, async->error);
-		return;
-	}
-
-	async->submit_bio_done(async->inode, async->rw, async->bio,
-			       async->mirror_num, async->bio_flags,
-			       async->bio_offset);
-}
-
-static void run_one_async_free(struct btrfs_work *work)
-{
-	struct async_submit_bio *async;
-
-	async = container_of(work, struct  async_submit_bio, work);
-	kfree(async);
-}
-
-int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
-			int rw, struct bio *bio, int mirror_num,
-			unsigned long bio_flags,
-			u64 bio_offset,
-			extent_submit_bio_hook_t *submit_bio_start,
-			extent_submit_bio_hook_t *submit_bio_done)
-{
-	struct async_submit_bio *async;
-
-	async = kmalloc(sizeof(*async), GFP_NOFS);
-	if (!async)
-		return -ENOMEM;
-
-	async->inode = inode;
-	async->rw = rw;
-	async->bio = bio;
-	async->mirror_num = mirror_num;
-	async->submit_bio_start = submit_bio_start;
-	async->submit_bio_done = submit_bio_done;
-
-	async->work.func = run_one_async_start;
-	async->work.ordered_func = run_one_async_done;
-	async->work.ordered_free = run_one_async_free;
-
-	async->work.flags = 0;
-	async->bio_flags = bio_flags;
-	async->bio_offset = bio_offset;
-
-	async->error = 0;
-
-	atomic_inc(&fs_info->nr_async_submits);
-
-	if (rw & REQ_SYNC)
-		btrfs_set_work_high_prio(&async->work);
-
-	btrfs_queue_worker(&fs_info->workers, &async->work);
-
-	while (atomic_read(&fs_info->async_submit_draining) &&
-	      atomic_read(&fs_info->nr_async_submits)) {
-		wait_event(fs_info->async_submit_wait,
-			   (atomic_read(&fs_info->nr_async_submits) == 0));
-	}
-
-	return 0;
-}
-
-static int btree_csum_one_bio(struct bio *bio)
-{
-	struct bio_vec *bvec = bio->bi_io_vec;
-	int bio_index = 0;
-	struct btrfs_root *root;
-	int ret = 0;
-
-	WARN_ON(bio->bi_vcnt <= 0);
-	while (bio_index < bio->bi_vcnt) {
-		root = BTRFS_I(bvec->bv_page->mapping->host)->root;
-		ret = csum_dirty_buffer(root, bvec->bv_page);
-		if (ret)
-			break;
-		bio_index++;
-		bvec++;
-	}
-	return ret;
-}
-
-static int __btree_submit_bio_start(struct inode *inode, int rw,
-				    struct bio *bio, int mirror_num,
-				    unsigned long bio_flags,
-				    u64 bio_offset)
-{
-	/*
-	 * when we're called for a write, we're already in the async
-	 * submission context.  Just jump into btrfs_map_bio
-	 */
-	return btree_csum_one_bio(bio);
-}
-
-static int __btree_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
-				 int mirror_num, unsigned long bio_flags,
-				 u64 bio_offset)
-{
-	/*
-	 * when we're called for a write, we're already in the async
-	 * submission context.  Just jump into btrfs_map_bio
-	 */
-	return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio, mirror_num, 1);
-}
-
-static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
-				 int mirror_num, unsigned long bio_flags,
-				 u64 bio_offset)
-{
-	int ret;
-
-	if (!(rw & REQ_WRITE)) {
-
-		/*
-		 * called for a read, do the setup so that checksum validation
-		 * can happen in the async kernel threads
-		 */
-		ret = btrfs_bio_wq_end_io(BTRFS_I(inode)->root->fs_info,
-					  bio, 1);
-		if (ret)
-			return ret;
-		return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
-				     mirror_num, 0);
-	}
-
-	/*
-	 * kthread helpers are used to submit writes so that checksumming
-	 * can happen in parallel across all CPUs
-	 */
-	return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
-				   inode, rw, bio, mirror_num, 0,
-				   bio_offset,
-				   __btree_submit_bio_start,
-				   __btree_submit_bio_done);
-}
-
-#ifdef CONFIG_MIGRATION
-static int btree_migratepage(struct address_space *mapping,
-			struct page *newpage, struct page *page,
-			enum migrate_mode mode)
-{
-	/*
-	 * we can't safely write a btree page from here,
-	 * we haven't done the locking hook
-	 */
-	if (PageDirty(page))
-		return -EAGAIN;
-	/*
-	 * Buffers may be managed in a filesystem specific way.
-	 * We must have no buffers or drop them.
-	 */
-	if (page_has_private(page) &&
-	    !try_to_release_page(page, GFP_KERNEL))
-		return -EAGAIN;
-	return migrate_page(mapping, newpage, page, mode);
-}
-#endif
-
-
-static int btree_writepages(struct address_space *mapping,
-			    struct writeback_control *wbc)
-{
-	struct extent_io_tree *tree;
-	tree = &BTRFS_I(mapping->host)->io_tree;
-	if (wbc->sync_mode == WB_SYNC_NONE) {
-		struct btrfs_root *root = BTRFS_I(mapping->host)->root;
-		u64 num_dirty;
-		unsigned long thresh = 32 * 1024 * 1024;
-
-		if (wbc->for_kupdate)
-			return 0;
-
-		/* this is a bit racy, but that's ok */
-		num_dirty = root->fs_info->dirty_metadata_bytes;
-		if (num_dirty < thresh)
-			return 0;
-	}
-	return btree_write_cache_pages(mapping, wbc);
-}
-
-static int btree_readpage(struct file *file, struct page *page)
-{
-	struct extent_io_tree *tree;
-	tree = &BTRFS_I(page->mapping->host)->io_tree;
-	return extent_read_full_page(tree, page, btree_get_extent, 0);
-}
-
-static int btree_releasepage(struct page *page, gfp_t gfp_flags)
-{
-	if (PageWriteback(page) || PageDirty(page))
-		return 0;
-	/*
-	 * We need to mask out eg. __GFP_HIGHMEM and __GFP_DMA32 as we're doing
-	 * slab allocation from alloc_extent_state down the callchain where
-	 * it'd hit a BUG_ON as those flags are not allowed.
-	 */
-	gfp_flags &= ~GFP_SLAB_BUG_MASK;
-
-	return try_release_extent_buffer(page, gfp_flags);
-}
-
-static void btree_invalidatepage(struct page *page, unsigned long offset)
-{
-	struct extent_io_tree *tree;
-	tree = &BTRFS_I(page->mapping->host)->io_tree;
-	extent_invalidatepage(tree, page, offset);
-	btree_releasepage(page, GFP_NOFS);
-	if (PagePrivate(page)) {
-		printk(KERN_WARNING "btrfs warning page private not zero "
-		       "on page %llu\n", (unsigned long long)page_offset(page));
-		ClearPagePrivate(page);
-		set_page_private(page, 0);
-		page_cache_release(page);
-	}
-}
-
-static int btree_set_page_dirty(struct page *page)
-{
-	struct extent_buffer *eb;
-
-	BUG_ON(!PagePrivate(page));
-	eb = (struct extent_buffer *)page->private;
-	BUG_ON(!eb);
-	BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
-	BUG_ON(!atomic_read(&eb->refs));
-	btrfs_assert_tree_locked(eb);
-	return __set_page_dirty_nobuffers(page);
-}
-
-static const struct address_space_operations btree_aops = {
-	.readpage	= btree_readpage,
-	.writepages	= btree_writepages,
-	.releasepage	= btree_releasepage,
-	.invalidatepage = btree_invalidatepage,
-#ifdef CONFIG_MIGRATION
-	.migratepage	= btree_migratepage,
-#endif
-	.set_page_dirty = btree_set_page_dirty,
-};
-
-int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
-			 u64 parent_transid)
-{
-	struct extent_buffer *buf = NULL;
-	struct inode *btree_inode = root->fs_info->btree_inode;
-	int ret = 0;
-
-	buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
-	if (!buf)
-		return 0;
-	read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
-				 buf, 0, WAIT_NONE, btree_get_extent, 0);
-	free_extent_buffer(buf);
-	return ret;
-}
-
-int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, u32 blocksize,
-			 int mirror_num, struct extent_buffer **eb)
-{
-	struct extent_buffer *buf = NULL;
-	struct inode *btree_inode = root->fs_info->btree_inode;
-	struct extent_io_tree *io_tree = &BTRFS_I(btree_inode)->io_tree;
-	int ret;
-
-	buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
-	if (!buf)
-		return 0;
-
-	set_bit(EXTENT_BUFFER_READAHEAD, &buf->bflags);
-
-	ret = read_extent_buffer_pages(io_tree, buf, 0, WAIT_PAGE_LOCK,
-				       btree_get_extent, mirror_num);
-	if (ret) {
-		free_extent_buffer(buf);
-		return ret;
-	}
-
-	if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) {
-		free_extent_buffer(buf);
-		return -EIO;
-	} else if (extent_buffer_uptodate(buf)) {
-		*eb = buf;
-	} else {
-		free_extent_buffer(buf);
-	}
-	return 0;
-}
-
-struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
-					    u64 bytenr, u32 blocksize)
-{
-	struct inode *btree_inode = root->fs_info->btree_inode;
-	struct extent_buffer *eb;
-	eb = find_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
-				bytenr, blocksize);
-	return eb;
-}
-
-struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
-						 u64 bytenr, u32 blocksize)
-{
-	struct inode *btree_inode = root->fs_info->btree_inode;
-	struct extent_buffer *eb;
-
-	eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
-				 bytenr, blocksize);
-	return eb;
-}
-
-
-int btrfs_write_tree_block(struct extent_buffer *buf)
-{
-	return filemap_fdatawrite_range(buf->pages[0]->mapping, buf->start,
-					buf->start + buf->len - 1);
-}
-
-int btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
-{
-	return filemap_fdatawait_range(buf->pages[0]->mapping,
-				       buf->start, buf->start + buf->len - 1);
-}
-
-struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
-				      u32 blocksize, u64 parent_transid)
-{
-	struct extent_buffer *buf = NULL;
-	int ret;
-
-	buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
-	if (!buf)
-		return NULL;
-
-	ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
-	return buf;
-
-}
-
-void clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
-		      struct extent_buffer *buf)
-{
-	if (btrfs_header_generation(buf) ==
-	    root->fs_info->running_transaction->transid) {
-		btrfs_assert_tree_locked(buf);
-
-		if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
-			spin_lock(&root->fs_info->delalloc_lock);
-			if (root->fs_info->dirty_metadata_bytes >= buf->len)
-				root->fs_info->dirty_metadata_bytes -= buf->len;
-			else {
-				spin_unlock(&root->fs_info->delalloc_lock);
-				btrfs_panic(root->fs_info, -EOVERFLOW,
-					  "Can't clear %lu bytes from "
-					  " dirty_mdatadata_bytes (%lu)",
-					  buf->len,
-					  root->fs_info->dirty_metadata_bytes);
-			}
-			spin_unlock(&root->fs_info->delalloc_lock);
-		}
-
-		/* ugh, clear_extent_buffer_dirty needs to lock the page */
-		btrfs_set_lock_blocking(buf);
-		clear_extent_buffer_dirty(buf);
-	}
-}
-
-static void __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
-			 u32 stripesize, struct btrfs_root *root,
-			 struct btrfs_fs_info *fs_info,
-			 u64 objectid)
-{
-	root->node = NULL;
-	root->commit_root = NULL;
-	root->sectorsize = sectorsize;
-	root->nodesize = nodesize;
-	root->leafsize = leafsize;
-	root->stripesize = stripesize;
-	root->ref_cows = 0;
-	root->track_dirty = 0;
-	root->in_radix = 0;
-	root->orphan_item_inserted = 0;
-	root->orphan_cleanup_state = 0;
-
-	root->objectid = objectid;
-	root->last_trans = 0;
-	root->highest_objectid = 0;
-	root->name = NULL;
-	root->inode_tree = RB_ROOT;
-	INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
-	root->block_rsv = NULL;
-	root->orphan_block_rsv = NULL;
-
-	INIT_LIST_HEAD(&root->dirty_list);
-	INIT_LIST_HEAD(&root->orphan_list);
-	INIT_LIST_HEAD(&root->root_list);
-	spin_lock_init(&root->orphan_lock);
-	spin_lock_init(&root->inode_lock);
-	spin_lock_init(&root->accounting_lock);
-	mutex_init(&root->objectid_mutex);
-	mutex_init(&root->log_mutex);
-	init_waitqueue_head(&root->log_writer_wait);
-	init_waitqueue_head(&root->log_commit_wait[0]);
-	init_waitqueue_head(&root->log_commit_wait[1]);
-	atomic_set(&root->log_commit[0], 0);
-	atomic_set(&root->log_commit[1], 0);
-	atomic_set(&root->log_writers, 0);
-	root->log_batch = 0;
-	root->log_transid = 0;
-	root->last_log_commit = 0;
-	extent_io_tree_init(&root->dirty_log_pages,
-			     fs_info->btree_inode->i_mapping);
-
-	memset(&root->root_key, 0, sizeof(root->root_key));
-	memset(&root->root_item, 0, sizeof(root->root_item));
-	memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
-	memset(&root->root_kobj, 0, sizeof(root->root_kobj));
-	root->defrag_trans_start = fs_info->generation;
-	init_completion(&root->kobj_unregister);
-	root->defrag_running = 0;
-	root->root_key.objectid = objectid;
-	root->anon_dev = 0;
-}
-
-static int __must_check find_and_setup_root(struct btrfs_root *tree_root,
-					    struct btrfs_fs_info *fs_info,
-					    u64 objectid,
-					    struct btrfs_root *root)
-{
-	int ret;
-	u32 blocksize;
-	u64 generation;
-
-	__setup_root(tree_root->nodesize, tree_root->leafsize,
-		     tree_root->sectorsize, tree_root->stripesize,
-		     root, fs_info, objectid);
-	ret = btrfs_find_last_root(tree_root, objectid,
-				   &root->root_item, &root->root_key);
-	if (ret > 0)
-		return -ENOENT;
-	else if (ret < 0)
-		return ret;
-
-	generation = btrfs_root_generation(&root->root_item);
-	blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
-	root->commit_root = NULL;
-	root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
-				     blocksize, generation);
-	if (!root->node || !btrfs_buffer_uptodate(root->node, generation, 0)) {
-		free_extent_buffer(root->node);
-		root->node = NULL;
-		return -EIO;
-	}
-	root->commit_root = btrfs_root_node(root);
-	return 0;
-}
-
-static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info)
-{
-	struct btrfs_root *root = kzalloc(sizeof(*root), GFP_NOFS);
-	if (root)
-		root->fs_info = fs_info;
-	return root;
-}
-
-static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
-					 struct btrfs_fs_info *fs_info)
-{
-	struct btrfs_root *root;
-	struct btrfs_root *tree_root = fs_info->tree_root;
-	struct extent_buffer *leaf;
-
-	root = btrfs_alloc_root(fs_info);
-	if (!root)
-		return ERR_PTR(-ENOMEM);
-
-	__setup_root(tree_root->nodesize, tree_root->leafsize,
-		     tree_root->sectorsize, tree_root->stripesize,
-		     root, fs_info, BTRFS_TREE_LOG_OBJECTID);
-
-	root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
-	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
-	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
-	/*
-	 * log trees do not get reference counted because they go away
-	 * before a real commit is actually done.  They do store pointers
-	 * to file data extents, and those reference counts still get
-	 * updated (along with back refs to the log tree).
-	 */
-	root->ref_cows = 0;
-
-	leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
-				      BTRFS_TREE_LOG_OBJECTID, NULL,
-				      0, 0, 0, 0);
-	if (IS_ERR(leaf)) {
-		kfree(root);
-		return ERR_CAST(leaf);
-	}
-
-	memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
-	btrfs_set_header_bytenr(leaf, leaf->start);
-	btrfs_set_header_generation(leaf, trans->transid);
-	btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
-	btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
-	root->node = leaf;
-
-	write_extent_buffer(root->node, root->fs_info->fsid,
-			    (unsigned long)btrfs_header_fsid(root->node),
-			    BTRFS_FSID_SIZE);
-	btrfs_mark_buffer_dirty(root->node);
-	btrfs_tree_unlock(root->node);
-	return root;
-}
-
-int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
-			     struct btrfs_fs_info *fs_info)
-{
-	struct btrfs_root *log_root;
-
-	log_root = alloc_log_tree(trans, fs_info);
-	if (IS_ERR(log_root))
-		return PTR_ERR(log_root);
-	WARN_ON(fs_info->log_root_tree);
-	fs_info->log_root_tree = log_root;
-	return 0;
-}
-
-int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
-		       struct btrfs_root *root)
-{
-	struct btrfs_root *log_root;
-	struct btrfs_inode_item *inode_item;
-
-	log_root = alloc_log_tree(trans, root->fs_info);
-	if (IS_ERR(log_root))
-		return PTR_ERR(log_root);
-
-	log_root->last_trans = trans->transid;
-	log_root->root_key.offset = root->root_key.objectid;
-
-	inode_item = &log_root->root_item.inode;
-	inode_item->generation = cpu_to_le64(1);
-	inode_item->size = cpu_to_le64(3);
-	inode_item->nlink = cpu_to_le32(1);
-	inode_item->nbytes = cpu_to_le64(root->leafsize);
-	inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
-
-	btrfs_set_root_node(&log_root->root_item, log_root->node);
-
-	WARN_ON(root->log_root);
-	root->log_root = log_root;
-	root->log_transid = 0;
-	root->last_log_commit = 0;
-	return 0;
-}
-
-struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
-					       struct btrfs_key *location)
-{
-	struct btrfs_root *root;
-	struct btrfs_fs_info *fs_info = tree_root->fs_info;
-	struct btrfs_path *path;
-	struct extent_buffer *l;
-	u64 generation;
-	u32 blocksize;
-	int ret = 0;
-
-	root = btrfs_alloc_root(fs_info);
-	if (!root)
-		return ERR_PTR(-ENOMEM);
-	if (location->offset == (u64)-1) {
-		ret = find_and_setup_root(tree_root, fs_info,
-					  location->objectid, root);
-		if (ret) {
-			kfree(root);
-			return ERR_PTR(ret);
-		}
-		goto out;
-	}
-
-	__setup_root(tree_root->nodesize, tree_root->leafsize,
-		     tree_root->sectorsize, tree_root->stripesize,
-		     root, fs_info, location->objectid);
-
-	path = btrfs_alloc_path();
-	if (!path) {
-		kfree(root);
-		return ERR_PTR(-ENOMEM);
-	}
-	ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
-	if (ret == 0) {
-		l = path->nodes[0];
-		read_extent_buffer(l, &root->root_item,
-				btrfs_item_ptr_offset(l, path->slots[0]),
-				sizeof(root->root_item));
-		memcpy(&root->root_key, location, sizeof(*location));
-	}
-	btrfs_free_path(path);
-	if (ret) {
-		kfree(root);
-		if (ret > 0)
-			ret = -ENOENT;
-		return ERR_PTR(ret);
-	}
-
-	generation = btrfs_root_generation(&root->root_item);
-	blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
-	root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
-				     blocksize, generation);
-	root->commit_root = btrfs_root_node(root);
-	BUG_ON(!root->node); /* -ENOMEM */
-out:
-	if (location->objectid != BTRFS_TREE_LOG_OBJECTID) {
-		root->ref_cows = 1;
-		btrfs_check_and_init_root_item(&root->root_item);
-	}
-
-	return root;
-}
-
-struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
-					      struct btrfs_key *location)
-{
-	struct btrfs_root *root;
-	int ret;
-
-	if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
-		return fs_info->tree_root;
-	if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
-		return fs_info->extent_root;
-	if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
-		return fs_info->chunk_root;
-	if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
-		return fs_info->dev_root;
-	if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
-		return fs_info->csum_root;
-again:
-	spin_lock(&fs_info->fs_roots_radix_lock);
-	root = radix_tree_lookup(&fs_info->fs_roots_radix,
-				 (unsigned long)location->objectid);
-	spin_unlock(&fs_info->fs_roots_radix_lock);
-	if (root)
-		return root;
-
-	root = btrfs_read_fs_root_no_radix(fs_info->tree_root, location);
-	if (IS_ERR(root))
-		return root;
-
-	root->free_ino_ctl = kzalloc(sizeof(*root->free_ino_ctl), GFP_NOFS);
-	root->free_ino_pinned = kzalloc(sizeof(*root->free_ino_pinned),
-					GFP_NOFS);
-	if (!root->free_ino_pinned || !root->free_ino_ctl) {
-		ret = -ENOMEM;
-		goto fail;
-	}
-
-	btrfs_init_free_ino_ctl(root);
-	mutex_init(&root->fs_commit_mutex);
-	spin_lock_init(&root->cache_lock);
-	init_waitqueue_head(&root->cache_wait);
-
-	ret = get_anon_bdev(&root->anon_dev);
-	if (ret)
-		goto fail;
-
-	if (btrfs_root_refs(&root->root_item) == 0) {
-		ret = -ENOENT;
-		goto fail;
-	}
-
-	ret = btrfs_find_orphan_item(fs_info->tree_root, location->objectid);
-	if (ret < 0)
-		goto fail;
-	if (ret == 0)
-		root->orphan_item_inserted = 1;
-
-	ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
-	if (ret)
-		goto fail;
-
-	spin_lock(&fs_info->fs_roots_radix_lock);
-	ret = radix_tree_insert(&fs_info->fs_roots_radix,
-				(unsigned long)root->root_key.objectid,
-				root);
-	if (ret == 0)
-		root->in_radix = 1;
-
-	spin_unlock(&fs_info->fs_roots_radix_lock);
-	radix_tree_preload_end();
-	if (ret) {
-		if (ret == -EEXIST) {
-			free_fs_root(root);
-			goto again;
-		}
-		goto fail;
-	}
-
-	ret = btrfs_find_dead_roots(fs_info->tree_root,
-				    root->root_key.objectid);
-	WARN_ON(ret);
-	return root;
-fail:
-	free_fs_root(root);
-	return ERR_PTR(ret);
-}
-
-static int btrfs_congested_fn(void *congested_data, int bdi_bits)
-{
-	struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
-	int ret = 0;
-	struct btrfs_device *device;
-	struct backing_dev_info *bdi;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(device, &info->fs_devices->devices, dev_list) {
-		if (!device->bdev)
-			continue;
-		bdi = blk_get_backing_dev_info(device->bdev);
-		if (bdi && bdi_congested(bdi, bdi_bits)) {
-			ret = 1;
-			break;
-		}
-	}
-	rcu_read_unlock();
-	return ret;
-}
-
-/*
- * If this fails, caller must call bdi_destroy() to get rid of the
- * bdi again.
- */
-static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
-{
-	int err;
-
-	bdi->capabilities = BDI_CAP_MAP_COPY;
-	err = bdi_setup_and_register(bdi, "btrfs", BDI_CAP_MAP_COPY);
-	if (err)
-		return err;
-
-	bdi->ra_pages	= default_backing_dev_info.ra_pages;
-	bdi->congested_fn	= btrfs_congested_fn;
-	bdi->congested_data	= info;
-	return 0;
-}
-
-/*
- * called by the kthread helper functions to finally call the bio end_io
- * functions.  This is where read checksum verification actually happens
- */
-static void end_workqueue_fn(struct btrfs_work *work)
-{
-	struct bio *bio;
-	struct end_io_wq *end_io_wq;
-	struct btrfs_fs_info *fs_info;
-	int error;
-
-	end_io_wq = container_of(work, struct end_io_wq, work);
-	bio = end_io_wq->bio;
-	fs_info = end_io_wq->info;
-
-	error = end_io_wq->error;
-	bio->bi_private = end_io_wq->private;
-	bio->bi_end_io = end_io_wq->end_io;
-	kfree(end_io_wq);
-	bio_endio(bio, error);
-}
-
-static int cleaner_kthread(void *arg)
-{
-	struct btrfs_root *root = arg;
-
-	do {
-		vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
-
-		if (!(root->fs_info->sb->s_flags & MS_RDONLY) &&
-		    mutex_trylock(&root->fs_info->cleaner_mutex)) {
-			btrfs_run_delayed_iputs(root);
-			btrfs_clean_old_snapshots(root);
-			mutex_unlock(&root->fs_info->cleaner_mutex);
-			btrfs_run_defrag_inodes(root->fs_info);
-		}
-
-		if (!try_to_freeze()) {
-			set_current_state(TASK_INTERRUPTIBLE);
-			if (!kthread_should_stop())
-				schedule();
-			__set_current_state(TASK_RUNNING);
-		}
-	} while (!kthread_should_stop());
-	return 0;
-}
-
-static int transaction_kthread(void *arg)
-{
-	struct btrfs_root *root = arg;
-	struct btrfs_trans_handle *trans;
-	struct btrfs_transaction *cur;
-	u64 transid;
-	unsigned long now;
-	unsigned long delay;
-	bool cannot_commit;
-
-	do {
-		cannot_commit = false;
-		delay = HZ * 30;
-		vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
-		mutex_lock(&root->fs_info->transaction_kthread_mutex);
-
-		spin_lock(&root->fs_info->trans_lock);
-		cur = root->fs_info->running_transaction;
-		if (!cur) {
-			spin_unlock(&root->fs_info->trans_lock);
-			goto sleep;
-		}
-
-		now = get_seconds();
-		if (!cur->blocked &&
-		    (now < cur->start_time || now - cur->start_time < 30)) {
-			spin_unlock(&root->fs_info->trans_lock);
-			delay = HZ * 5;
-			goto sleep;
-		}
-		transid = cur->transid;
-		spin_unlock(&root->fs_info->trans_lock);
-
-		/* If the file system is aborted, this will always fail. */
-		trans = btrfs_join_transaction(root);
-		if (IS_ERR(trans)) {
-			cannot_commit = true;
-			goto sleep;
-		}
-		if (transid == trans->transid) {
-			btrfs_commit_transaction(trans, root);
-		} else {
-			btrfs_end_transaction(trans, root);
-		}
-sleep:
-		wake_up_process(root->fs_info->cleaner_kthread);
-		mutex_unlock(&root->fs_info->transaction_kthread_mutex);
-
-		if (!try_to_freeze()) {
-			set_current_state(TASK_INTERRUPTIBLE);
-			if (!kthread_should_stop() &&
-			    (!btrfs_transaction_blocked(root->fs_info) ||
-			     cannot_commit))
-				schedule_timeout(delay);
-			__set_current_state(TASK_RUNNING);
-		}
-	} while (!kthread_should_stop());
-	return 0;
-}
-
-/*
- * this will find the highest generation in the array of
- * root backups.  The index of the highest array is returned,
- * or -1 if we can't find anything.
- *
- * We check to make sure the array is valid by comparing the
- * generation of the latest  root in the array with the generation
- * in the super block.  If they don't match we pitch it.
- */
-static int find_newest_super_backup(struct btrfs_fs_info *info, u64 newest_gen)
-{
-	u64 cur;
-	int newest_index = -1;
-	struct btrfs_root_backup *root_backup;
-	int i;
-
-	for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
-		root_backup = info->super_copy->super_roots + i;
-		cur = btrfs_backup_tree_root_gen(root_backup);
-		if (cur == newest_gen)
-			newest_index = i;
-	}
-
-	/* check to see if we actually wrapped around */
-	if (newest_index == BTRFS_NUM_BACKUP_ROOTS - 1) {
-		root_backup = info->super_copy->super_roots;
-		cur = btrfs_backup_tree_root_gen(root_backup);
-		if (cur == newest_gen)
-			newest_index = 0;
-	}
-	return newest_index;
-}
-
-
-/*
- * find the oldest backup so we know where to store new entries
- * in the backup array.  This will set the backup_root_index
- * field in the fs_info struct
- */
-static void find_oldest_super_backup(struct btrfs_fs_info *info,
-				     u64 newest_gen)
-{
-	int newest_index = -1;
-
-	newest_index = find_newest_super_backup(info, newest_gen);
-	/* if there was garbage in there, just move along */
-	if (newest_index == -1) {
-		info->backup_root_index = 0;
-	} else {
-		info->backup_root_index = (newest_index + 1) % BTRFS_NUM_BACKUP_ROOTS;
-	}
-}
-
-/*
- * copy all the root pointers into the super backup array.
- * this will bump the backup pointer by one when it is
- * done
- */
-static void backup_super_roots(struct btrfs_fs_info *info)
-{
-	int next_backup;
-	struct btrfs_root_backup *root_backup;
-	int last_backup;
-
-	next_backup = info->backup_root_index;
-	last_backup = (next_backup + BTRFS_NUM_BACKUP_ROOTS - 1) %
-		BTRFS_NUM_BACKUP_ROOTS;
-
-	/*
-	 * just overwrite the last backup if we're at the same generation
-	 * this happens only at umount
-	 */
-	root_backup = info->super_for_commit->super_roots + last_backup;
-	if (btrfs_backup_tree_root_gen(root_backup) ==
-	    btrfs_header_generation(info->tree_root->node))
-		next_backup = last_backup;
-
-	root_backup = info->super_for_commit->super_roots + next_backup;
-
-	/*
-	 * make sure all of our padding and empty slots get zero filled
-	 * regardless of which ones we use today
-	 */
-	memset(root_backup, 0, sizeof(*root_backup));
-
-	info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
-
-	btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
-	btrfs_set_backup_tree_root_gen(root_backup,
-			       btrfs_header_generation(info->tree_root->node));
-
-	btrfs_set_backup_tree_root_level(root_backup,
-			       btrfs_header_level(info->tree_root->node));
-
-	btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
-	btrfs_set_backup_chunk_root_gen(root_backup,
-			       btrfs_header_generation(info->chunk_root->node));
-	btrfs_set_backup_chunk_root_level(root_backup,
-			       btrfs_header_level(info->chunk_root->node));
-
-	btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start);
-	btrfs_set_backup_extent_root_gen(root_backup,
-			       btrfs_header_generation(info->extent_root->node));
-	btrfs_set_backup_extent_root_level(root_backup,
-			       btrfs_header_level(info->extent_root->node));
-
-	/*
-	 * we might commit during log recovery, which happens before we set
-	 * the fs_root.  Make sure it is valid before we fill it in.
-	 */
-	if (info->fs_root && info->fs_root->node) {
-		btrfs_set_backup_fs_root(root_backup,
-					 info->fs_root->node->start);
-		btrfs_set_backup_fs_root_gen(root_backup,
-			       btrfs_header_generation(info->fs_root->node));
-		btrfs_set_backup_fs_root_level(root_backup,
-			       btrfs_header_level(info->fs_root->node));
-	}
-
-	btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
-	btrfs_set_backup_dev_root_gen(root_backup,
-			       btrfs_header_generation(info->dev_root->node));
-	btrfs_set_backup_dev_root_level(root_backup,
-				       btrfs_header_level(info->dev_root->node));
-
-	btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start);
-	btrfs_set_backup_csum_root_gen(root_backup,
-			       btrfs_header_generation(info->csum_root->node));
-	btrfs_set_backup_csum_root_level(root_backup,
-			       btrfs_header_level(info->csum_root->node));
-
-	btrfs_set_backup_total_bytes(root_backup,
-			     btrfs_super_total_bytes(info->super_copy));
-	btrfs_set_backup_bytes_used(root_backup,
-			     btrfs_super_bytes_used(info->super_copy));
-	btrfs_set_backup_num_devices(root_backup,
-			     btrfs_super_num_devices(info->super_copy));
-
-	/*
-	 * if we don't copy this out to the super_copy, it won't get remembered
-	 * for the next commit
-	 */
-	memcpy(&info->super_copy->super_roots,
-	       &info->super_for_commit->super_roots,
-	       sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
-}
-
-/*
- * this copies info out of the root backup array and back into
- * the in-memory super block.  It is meant to help iterate through
- * the array, so you send it the number of backups you've already
- * tried and the last backup index you used.
- *
- * this returns -1 when it has tried all the backups
- */
-static noinline int next_root_backup(struct btrfs_fs_info *info,
-				     struct btrfs_super_block *super,
-				     int *num_backups_tried, int *backup_index)
-{
-	struct btrfs_root_backup *root_backup;
-	int newest = *backup_index;
-
-	if (*num_backups_tried == 0) {
-		u64 gen = btrfs_super_generation(super);
-
-		newest = find_newest_super_backup(info, gen);
-		if (newest == -1)
-			return -1;
-
-		*backup_index = newest;
-		*num_backups_tried = 1;
-	} else if (*num_backups_tried == BTRFS_NUM_BACKUP_ROOTS) {
-		/* we've tried all the backups, all done */
-		return -1;
-	} else {
-		/* jump to the next oldest backup */
-		newest = (*backup_index + BTRFS_NUM_BACKUP_ROOTS - 1) %
-			BTRFS_NUM_BACKUP_ROOTS;
-		*backup_index = newest;
-		*num_backups_tried += 1;
-	}
-	root_backup = super->super_roots + newest;
-
-	btrfs_set_super_generation(super,
-				   btrfs_backup_tree_root_gen(root_backup));
-	btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
-	btrfs_set_super_root_level(super,
-				   btrfs_backup_tree_root_level(root_backup));
-	btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
-
-	/*
-	 * fixme: the total bytes and num_devices need to match or we should
-	 * need a fsck
-	 */
-	btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
-	btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
-	return 0;
-}
-
-/* helper to cleanup tree roots */
-static void free_root_pointers(struct btrfs_fs_info *info, int chunk_root)
-{
-	free_extent_buffer(info->tree_root->node);
-	free_extent_buffer(info->tree_root->commit_root);
-	free_extent_buffer(info->dev_root->node);
-	free_extent_buffer(info->dev_root->commit_root);
-	free_extent_buffer(info->extent_root->node);
-	free_extent_buffer(info->extent_root->commit_root);
-	free_extent_buffer(info->csum_root->node);
-	free_extent_buffer(info->csum_root->commit_root);
-
-	info->tree_root->node = NULL;
-	info->tree_root->commit_root = NULL;
-	info->dev_root->node = NULL;
-	info->dev_root->commit_root = NULL;
-	info->extent_root->node = NULL;
-	info->extent_root->commit_root = NULL;
-	info->csum_root->node = NULL;
-	info->csum_root->commit_root = NULL;
-
-	if (chunk_root) {
-		free_extent_buffer(info->chunk_root->node);
-		free_extent_buffer(info->chunk_root->commit_root);
-		info->chunk_root->node = NULL;
-		info->chunk_root->commit_root = NULL;
-	}
-}
-
-
-int open_ctree(struct super_block *sb,
-	       struct btrfs_fs_devices *fs_devices,
-	       char *options)
-{
-	u32 sectorsize;
-	u32 nodesize;
-	u32 leafsize;
-	u32 blocksize;
-	u32 stripesize;
-	u64 generation;
-	u64 features;
-	struct btrfs_key location;
-	struct buffer_head *bh;
-	struct btrfs_super_block *disk_super;
-	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
-	struct btrfs_root *tree_root;
-	struct btrfs_root *extent_root;
-	struct btrfs_root *csum_root;
-	struct btrfs_root *chunk_root;
-	struct btrfs_root *dev_root;
-	struct btrfs_root *log_tree_root;
-	int ret;
-	int err = -EINVAL;
-	int num_backups_tried = 0;
-	int backup_index = 0;
-
-	tree_root = fs_info->tree_root = btrfs_alloc_root(fs_info);
-	extent_root = fs_info->extent_root = btrfs_alloc_root(fs_info);
-	csum_root = fs_info->csum_root = btrfs_alloc_root(fs_info);
-	chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info);
-	dev_root = fs_info->dev_root = btrfs_alloc_root(fs_info);
-
-	if (!tree_root || !extent_root || !csum_root ||
-	    !chunk_root || !dev_root) {
-		err = -ENOMEM;
-		goto fail;
-	}
-
-	ret = init_srcu_struct(&fs_info->subvol_srcu);
-	if (ret) {
-		err = ret;
-		goto fail;
-	}
-
-	ret = setup_bdi(fs_info, &fs_info->bdi);
-	if (ret) {
-		err = ret;
-		goto fail_srcu;
-	}
-
-	fs_info->btree_inode = new_inode(sb);
-	if (!fs_info->btree_inode) {
-		err = -ENOMEM;
-		goto fail_bdi;
-	}
-
-	mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
-
-	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
-	INIT_LIST_HEAD(&fs_info->trans_list);
-	INIT_LIST_HEAD(&fs_info->dead_roots);
-	INIT_LIST_HEAD(&fs_info->delayed_iputs);
-	INIT_LIST_HEAD(&fs_info->hashers);
-	INIT_LIST_HEAD(&fs_info->delalloc_inodes);
-	INIT_LIST_HEAD(&fs_info->ordered_operations);
-	INIT_LIST_HEAD(&fs_info->caching_block_groups);
-	spin_lock_init(&fs_info->delalloc_lock);
-	spin_lock_init(&fs_info->trans_lock);
-	spin_lock_init(&fs_info->ref_cache_lock);
-	spin_lock_init(&fs_info->fs_roots_radix_lock);
-	spin_lock_init(&fs_info->delayed_iput_lock);
-	spin_lock_init(&fs_info->defrag_inodes_lock);
-	spin_lock_init(&fs_info->free_chunk_lock);
-	mutex_init(&fs_info->reloc_mutex);
-
-	init_completion(&fs_info->kobj_unregister);
-	INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
-	INIT_LIST_HEAD(&fs_info->space_info);
-	btrfs_mapping_init(&fs_info->mapping_tree);
-	btrfs_init_block_rsv(&fs_info->global_block_rsv);
-	btrfs_init_block_rsv(&fs_info->delalloc_block_rsv);
-	btrfs_init_block_rsv(&fs_info->trans_block_rsv);
-	btrfs_init_block_rsv(&fs_info->chunk_block_rsv);
-	btrfs_init_block_rsv(&fs_info->empty_block_rsv);
-	btrfs_init_block_rsv(&fs_info->delayed_block_rsv);
-	atomic_set(&fs_info->nr_async_submits, 0);
-	atomic_set(&fs_info->async_delalloc_pages, 0);
-	atomic_set(&fs_info->async_submit_draining, 0);
-	atomic_set(&fs_info->nr_async_bios, 0);
-	atomic_set(&fs_info->defrag_running, 0);
-	fs_info->sb = sb;
-	fs_info->max_inline = 8192 * 1024;
-	fs_info->metadata_ratio = 0;
-	fs_info->defrag_inodes = RB_ROOT;
-	fs_info->trans_no_join = 0;
-	fs_info->free_chunk_space = 0;
-
-	/* readahead state */
-	INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_WAIT);
-	spin_lock_init(&fs_info->reada_lock);
-
-	fs_info->thread_pool_size = min_t(unsigned long,
-					  num_online_cpus() + 2, 8);
-
-	INIT_LIST_HEAD(&fs_info->ordered_extents);
-	spin_lock_init(&fs_info->ordered_extent_lock);
-	fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
-					GFP_NOFS);
-	if (!fs_info->delayed_root) {
-		err = -ENOMEM;
-		goto fail_iput;
-	}
-	btrfs_init_delayed_root(fs_info->delayed_root);
-
-	mutex_init(&fs_info->scrub_lock);
-	atomic_set(&fs_info->scrubs_running, 0);
-	atomic_set(&fs_info->scrub_pause_req, 0);
-	atomic_set(&fs_info->scrubs_paused, 0);
-	atomic_set(&fs_info->scrub_cancel_req, 0);
-	init_waitqueue_head(&fs_info->scrub_pause_wait);
-	init_rwsem(&fs_info->scrub_super_lock);
-	fs_info->scrub_workers_refcnt = 0;
-#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
-	fs_info->check_integrity_print_mask = 0;
-#endif
-
-	spin_lock_init(&fs_info->balance_lock);
-	mutex_init(&fs_info->balance_mutex);
-	atomic_set(&fs_info->balance_running, 0);
-	atomic_set(&fs_info->balance_pause_req, 0);
-	atomic_set(&fs_info->balance_cancel_req, 0);
-	fs_info->balance_ctl = NULL;
-	init_waitqueue_head(&fs_info->balance_wait_q);
-
-	sb->s_blocksize = 4096;
-	sb->s_blocksize_bits = blksize_bits(4096);
-	sb->s_bdi = &fs_info->bdi;
-
-	fs_info->btree_inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
-	set_nlink(fs_info->btree_inode, 1);
-	/*
-	 * we set the i_size on the btree inode to the max possible int.
-	 * the real end of the address space is determined by all of
-	 * the devices in the system
-	 */
-	fs_info->btree_inode->i_size = OFFSET_MAX;
-	fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
-	fs_info->btree_inode->i_mapping->backing_dev_info = &fs_info->bdi;
-
-	RB_CLEAR_NODE(&BTRFS_I(fs_info->btree_inode)->rb_node);
-	extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree,
-			     fs_info->btree_inode->i_mapping);
-	BTRFS_I(fs_info->btree_inode)->io_tree.track_uptodate = 0;
-	extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree);
-
-	BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops;
-
-	BTRFS_I(fs_info->btree_inode)->root = tree_root;
-	memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
-	       sizeof(struct btrfs_key));
-	BTRFS_I(fs_info->btree_inode)->dummy_inode = 1;
-	insert_inode_hash(fs_info->btree_inode);
-
-	spin_lock_init(&fs_info->block_group_cache_lock);
-	fs_info->block_group_cache_tree = RB_ROOT;
-
-	extent_io_tree_init(&fs_info->freed_extents[0],
-			     fs_info->btree_inode->i_mapping);
-	extent_io_tree_init(&fs_info->freed_extents[1],
-			     fs_info->btree_inode->i_mapping);
-	fs_info->pinned_extents = &fs_info->freed_extents[0];
-	fs_info->do_barriers = 1;
-
-
-	mutex_init(&fs_info->ordered_operations_mutex);
-	mutex_init(&fs_info->tree_log_mutex);
-	mutex_init(&fs_info->chunk_mutex);
-	mutex_init(&fs_info->transaction_kthread_mutex);
-	mutex_init(&fs_info->cleaner_mutex);
-	mutex_init(&fs_info->volume_mutex);
-	init_rwsem(&fs_info->extent_commit_sem);
-	init_rwsem(&fs_info->cleanup_work_sem);
-	init_rwsem(&fs_info->subvol_sem);
-
-	btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
-	btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
-
-	init_waitqueue_head(&fs_info->transaction_throttle);
-	init_waitqueue_head(&fs_info->transaction_wait);
-	init_waitqueue_head(&fs_info->transaction_blocked_wait);
-	init_waitqueue_head(&fs_info->async_submit_wait);
-
-	__setup_root(4096, 4096, 4096, 4096, tree_root,
-		     fs_info, BTRFS_ROOT_TREE_OBJECTID);
-
-	invalidate_bdev(fs_devices->latest_bdev);
-	bh = btrfs_read_dev_super(fs_devices->latest_bdev);
-	if (!bh) {
-		err = -EINVAL;
-		goto fail_alloc;
-	}
-
-	memcpy(fs_info->super_copy, bh->b_data, sizeof(*fs_info->super_copy));
-	memcpy(fs_info->super_for_commit, fs_info->super_copy,
-	       sizeof(*fs_info->super_for_commit));
-	brelse(bh);
-
-	memcpy(fs_info->fsid, fs_info->super_copy->fsid, BTRFS_FSID_SIZE);
-
-	disk_super = fs_info->super_copy;
-	if (!btrfs_super_root(disk_super))
-		goto fail_alloc;
-
-	/* check FS state, whether FS is broken. */
-	fs_info->fs_state |= btrfs_super_flags(disk_super);
-
-	ret = btrfs_check_super_valid(fs_info, sb->s_flags & MS_RDONLY);
-	if (ret) {
-		printk(KERN_ERR "btrfs: superblock contains fatal errors\n");
-		err = ret;
-		goto fail_alloc;
-	}
-
-	/*
-	 * run through our array of backup supers and setup
-	 * our ring pointer to the oldest one
-	 */
-	generation = btrfs_super_generation(disk_super);
-	find_oldest_super_backup(fs_info, generation);
-
-	/*
-	 * In the long term, we'll store the compression type in the super
-	 * block, and it'll be used for per file compression control.
-	 */
-	fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
-
-	ret = btrfs_parse_options(tree_root, options);
-	if (ret) {
-		err = ret;
-		goto fail_alloc;
-	}
-
-	features = btrfs_super_incompat_flags(disk_super) &
-		~BTRFS_FEATURE_INCOMPAT_SUPP;
-	if (features) {
-		printk(KERN_ERR "BTRFS: couldn't mount because of "
-		       "unsupported optional features (%Lx).\n",
-		       (unsigned long long)features);
-		err = -EINVAL;
-		goto fail_alloc;
-	}
-
-	if (btrfs_super_leafsize(disk_super) !=
-	    btrfs_super_nodesize(disk_super)) {
-		printk(KERN_ERR "BTRFS: couldn't mount because metadata "
-		       "blocksizes don't match.  node %d leaf %d\n",
-		       btrfs_super_nodesize(disk_super),
-		       btrfs_super_leafsize(disk_super));
-		err = -EINVAL;
-		goto fail_alloc;
-	}
-	if (btrfs_super_leafsize(disk_super) > BTRFS_MAX_METADATA_BLOCKSIZE) {
-		printk(KERN_ERR "BTRFS: couldn't mount because metadata "
-		       "blocksize (%d) was too large\n",
-		       btrfs_super_leafsize(disk_super));
-		err = -EINVAL;
-		goto fail_alloc;
-	}
-
-	features = btrfs_super_incompat_flags(disk_super);
-	features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
-	if (tree_root->fs_info->compress_type & BTRFS_COMPRESS_LZO)
-		features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
-
-	/*
-	 * flag our filesystem as having big metadata blocks if
-	 * they are bigger than the page size
-	 */
-	if (btrfs_super_leafsize(disk_super) > PAGE_CACHE_SIZE) {
-		if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA))
-			printk(KERN_INFO "btrfs flagging fs with big metadata feature\n");
-		features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
-	}
-
-	nodesize = btrfs_super_nodesize(disk_super);
-	leafsize = btrfs_super_leafsize(disk_super);
-	sectorsize = btrfs_super_sectorsize(disk_super);
-	stripesize = btrfs_super_stripesize(disk_super);
-
-	/*
-	 * mixed block groups end up with duplicate but slightly offset
-	 * extent buffers for the same range.  It leads to corruptions
-	 */
-	if ((features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
-	    (sectorsize != leafsize)) {
-		printk(KERN_WARNING "btrfs: unequal leaf/node/sector sizes "
-				"are not allowed for mixed block groups on %s\n",
-				sb->s_id);
-		goto fail_alloc;
-	}
-
-	btrfs_set_super_incompat_flags(disk_super, features);
-
-	features = btrfs_super_compat_ro_flags(disk_super) &
-		~BTRFS_FEATURE_COMPAT_RO_SUPP;
-	if (!(sb->s_flags & MS_RDONLY) && features) {
-		printk(KERN_ERR "BTRFS: couldn't mount RDWR because of "
-		       "unsupported option features (%Lx).\n",
-		       (unsigned long long)features);
-		err = -EINVAL;
-		goto fail_alloc;
-	}
-
-	btrfs_init_workers(&fs_info->generic_worker,
-			   "genwork", 1, NULL);
-
-	btrfs_init_workers(&fs_info->workers, "worker",
-			   fs_info->thread_pool_size,
-			   &fs_info->generic_worker);
-
-	btrfs_init_workers(&fs_info->delalloc_workers, "delalloc",
-			   fs_info->thread_pool_size,
-			   &fs_info->generic_worker);
-
-	btrfs_init_workers(&fs_info->submit_workers, "submit",
-			   min_t(u64, fs_devices->num_devices,
-			   fs_info->thread_pool_size),
-			   &fs_info->generic_worker);
-
-	btrfs_init_workers(&fs_info->caching_workers, "cache",
-			   2, &fs_info->generic_worker);
-
-	/* a higher idle thresh on the submit workers makes it much more
-	 * likely that bios will be send down in a sane order to the
-	 * devices
-	 */
-	fs_info->submit_workers.idle_thresh = 64;
-
-	fs_info->workers.idle_thresh = 16;
-	fs_info->workers.ordered = 1;
-
-	fs_info->delalloc_workers.idle_thresh = 2;
-	fs_info->delalloc_workers.ordered = 1;
-
-	btrfs_init_workers(&fs_info->fixup_workers, "fixup", 1,
-			   &fs_info->generic_worker);
-	btrfs_init_workers(&fs_info->endio_workers, "endio",
-			   fs_info->thread_pool_size,
-			   &fs_info->generic_worker);
-	btrfs_init_workers(&fs_info->endio_meta_workers, "endio-meta",
-			   fs_info->thread_pool_size,
-			   &fs_info->generic_worker);
-	btrfs_init_workers(&fs_info->endio_meta_write_workers,
-			   "endio-meta-write", fs_info->thread_pool_size,
-			   &fs_info->generic_worker);
-	btrfs_init_workers(&fs_info->endio_write_workers, "endio-write",
-			   fs_info->thread_pool_size,
-			   &fs_info->generic_worker);
-	btrfs_init_workers(&fs_info->endio_freespace_worker, "freespace-write",
-			   1, &fs_info->generic_worker);
-	btrfs_init_workers(&fs_info->delayed_workers, "delayed-meta",
-			   fs_info->thread_pool_size,
-			   &fs_info->generic_worker);
-	btrfs_init_workers(&fs_info->readahead_workers, "readahead",
-			   fs_info->thread_pool_size,
-			   &fs_info->generic_worker);
-
-	/*
-	 * endios are largely parallel and should have a very
-	 * low idle thresh
-	 */
-	fs_info->endio_workers.idle_thresh = 4;
-	fs_info->endio_meta_workers.idle_thresh = 4;
-
-	fs_info->endio_write_workers.idle_thresh = 2;
-	fs_info->endio_meta_write_workers.idle_thresh = 2;
-	fs_info->readahead_workers.idle_thresh = 2;
-
-	/*
-	 * btrfs_start_workers can really only fail because of ENOMEM so just
-	 * return -ENOMEM if any of these fail.
-	 */
-	ret = btrfs_start_workers(&fs_info->workers);
-	ret |= btrfs_start_workers(&fs_info->generic_worker);
-	ret |= btrfs_start_workers(&fs_info->submit_workers);
-	ret |= btrfs_start_workers(&fs_info->delalloc_workers);
-	ret |= btrfs_start_workers(&fs_info->fixup_workers);
-	ret |= btrfs_start_workers(&fs_info->endio_workers);
-	ret |= btrfs_start_workers(&fs_info->endio_meta_workers);
-	ret |= btrfs_start_workers(&fs_info->endio_meta_write_workers);
-	ret |= btrfs_start_workers(&fs_info->endio_write_workers);
-	ret |= btrfs_start_workers(&fs_info->endio_freespace_worker);
-	ret |= btrfs_start_workers(&fs_info->delayed_workers);
-	ret |= btrfs_start_workers(&fs_info->caching_workers);
-	ret |= btrfs_start_workers(&fs_info->readahead_workers);
-	if (ret) {
-		ret = -ENOMEM;
-		goto fail_sb_buffer;
-	}
-
-	fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
-	fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
-				    4 * 1024 * 1024 / PAGE_CACHE_SIZE);
-
-	tree_root->nodesize = nodesize;
-	tree_root->leafsize = leafsize;
-	tree_root->sectorsize = sectorsize;
-	tree_root->stripesize = stripesize;
-
-	sb->s_blocksize = sectorsize;
-	sb->s_blocksize_bits = blksize_bits(sectorsize);
-
-	if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
-		    sizeof(disk_super->magic))) {
-		printk(KERN_INFO "btrfs: valid FS not found on %s\n", sb->s_id);
-		goto fail_sb_buffer;
-	}
-
-	if (sectorsize != PAGE_SIZE) {
-		printk(KERN_WARNING "btrfs: Incompatible sector size(%lu) "
-		       "found on %s\n", (unsigned long)sectorsize, sb->s_id);
-		goto fail_sb_buffer;
-	}
-
-	mutex_lock(&fs_info->chunk_mutex);
-	ret = btrfs_read_sys_array(tree_root);
-	mutex_unlock(&fs_info->chunk_mutex);
-	if (ret) {
-		printk(KERN_WARNING "btrfs: failed to read the system "
-		       "array on %s\n", sb->s_id);
-		goto fail_sb_buffer;
-	}
-
-	blocksize = btrfs_level_size(tree_root,
-				     btrfs_super_chunk_root_level(disk_super));
-	generation = btrfs_super_chunk_root_generation(disk_super);
-
-	__setup_root(nodesize, leafsize, sectorsize, stripesize,
-		     chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
-
-	chunk_root->node = read_tree_block(chunk_root,
-					   btrfs_super_chunk_root(disk_super),
-					   blocksize, generation);
-	BUG_ON(!chunk_root->node); /* -ENOMEM */
-	if (!test_bit(EXTENT_BUFFER_UPTODATE, &chunk_root->node->bflags)) {
-		printk(KERN_WARNING "btrfs: failed to read chunk root on %s\n",
-		       sb->s_id);
-		goto fail_tree_roots;
-	}
-	btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
-	chunk_root->commit_root = btrfs_root_node(chunk_root);
-
-	read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
-	   (unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
-	   BTRFS_UUID_SIZE);
-
-	ret = btrfs_read_chunk_tree(chunk_root);
-	if (ret) {
-		printk(KERN_WARNING "btrfs: failed to read chunk tree on %s\n",
-		       sb->s_id);
-		goto fail_tree_roots;
-	}
-
-	btrfs_close_extra_devices(fs_devices);
-
-	if (!fs_devices->latest_bdev) {
-		printk(KERN_CRIT "btrfs: failed to read devices on %s\n",
-		       sb->s_id);
-		goto fail_tree_roots;
-	}
-
-retry_root_backup:
-	blocksize = btrfs_level_size(tree_root,
-				     btrfs_super_root_level(disk_super));
-	generation = btrfs_super_generation(disk_super);
-
-	tree_root->node = read_tree_block(tree_root,
-					  btrfs_super_root(disk_super),
-					  blocksize, generation);
-	if (!tree_root->node ||
-	    !test_bit(EXTENT_BUFFER_UPTODATE, &tree_root->node->bflags)) {
-		printk(KERN_WARNING "btrfs: failed to read tree root on %s\n",
-		       sb->s_id);
-
-		goto recovery_tree_root;
-	}
-
-	btrfs_set_root_node(&tree_root->root_item, tree_root->node);
-	tree_root->commit_root = btrfs_root_node(tree_root);
-
-	ret = find_and_setup_root(tree_root, fs_info,
-				  BTRFS_EXTENT_TREE_OBJECTID, extent_root);
-	if (ret)
-		goto recovery_tree_root;
-	extent_root->track_dirty = 1;
-
-	ret = find_and_setup_root(tree_root, fs_info,
-				  BTRFS_DEV_TREE_OBJECTID, dev_root);
-	if (ret)
-		goto recovery_tree_root;
-	dev_root->track_dirty = 1;
-
-	ret = find_and_setup_root(tree_root, fs_info,
-				  BTRFS_CSUM_TREE_OBJECTID, csum_root);
-	if (ret)
-		goto recovery_tree_root;
-
-	csum_root->track_dirty = 1;
-
-	fs_info->generation = generation;
-	fs_info->last_trans_committed = generation;
-
-	ret = btrfs_init_space_info(fs_info);
-	if (ret) {
-		printk(KERN_ERR "Failed to initial space info: %d\n", ret);
-		goto fail_block_groups;
-	}
-
-	ret = btrfs_read_block_groups(extent_root);
-	if (ret) {
-		printk(KERN_ERR "Failed to read block groups: %d\n", ret);
-		goto fail_block_groups;
-	}
-
-	fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
-					       "btrfs-cleaner");
-	if (IS_ERR(fs_info->cleaner_kthread))
-		goto fail_block_groups;
-
-	fs_info->transaction_kthread = kthread_run(transaction_kthread,
-						   tree_root,
-						   "btrfs-transaction");
-	if (IS_ERR(fs_info->transaction_kthread))
-		goto fail_cleaner;
-
-	if (!btrfs_test_opt(tree_root, SSD) &&
-	    !btrfs_test_opt(tree_root, NOSSD) &&
-	    !fs_info->fs_devices->rotating) {
-		printk(KERN_INFO "Btrfs detected SSD devices, enabling SSD "
-		       "mode\n");
-		btrfs_set_opt(fs_info->mount_opt, SSD);
-	}
-
-#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
-	if (btrfs_test_opt(tree_root, CHECK_INTEGRITY)) {
-		ret = btrfsic_mount(tree_root, fs_devices,
-				    btrfs_test_opt(tree_root,
-					CHECK_INTEGRITY_INCLUDING_EXTENT_DATA) ?
-				    1 : 0,
-				    fs_info->check_integrity_print_mask);
-		if (ret)
-			printk(KERN_WARNING "btrfs: failed to initialize"
-			       " integrity check module %s\n", sb->s_id);
-	}
-#endif
-
-	/* do not make disk changes in broken FS */
-	if (btrfs_super_log_root(disk_super) != 0 &&
-	    !(fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)) {
-		u64 bytenr = btrfs_super_log_root(disk_super);
-
-		if (fs_devices->rw_devices == 0) {
-			printk(KERN_WARNING "Btrfs log replay required "
-			       "on RO media\n");
-			err = -EIO;
-			goto fail_trans_kthread;
-		}
-		blocksize =
-		     btrfs_level_size(tree_root,
-				      btrfs_super_log_root_level(disk_super));
-
-		log_tree_root = btrfs_alloc_root(fs_info);
-		if (!log_tree_root) {
-			err = -ENOMEM;
-			goto fail_trans_kthread;
-		}
-
-		__setup_root(nodesize, leafsize, sectorsize, stripesize,
-			     log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
-
-		log_tree_root->node = read_tree_block(tree_root, bytenr,
-						      blocksize,
-						      generation + 1);
-		/* returns with log_tree_root freed on success */
-		ret = btrfs_recover_log_trees(log_tree_root);
-		if (ret) {
-			btrfs_error(tree_root->fs_info, ret,
-				    "Failed to recover log tree");
-			free_extent_buffer(log_tree_root->node);
-			kfree(log_tree_root);
-			goto fail_trans_kthread;
-		}
-
-		if (sb->s_flags & MS_RDONLY) {
-			ret = btrfs_commit_super(tree_root);
-			if (ret)
-				goto fail_trans_kthread;
-		}
-	}
-
-	ret = btrfs_find_orphan_roots(tree_root);
-	if (ret)
-		goto fail_trans_kthread;
-
-	if (!(sb->s_flags & MS_RDONLY)) {
-		ret = btrfs_cleanup_fs_roots(fs_info);
-		if (ret) {
-			}
-
-		ret = btrfs_recover_relocation(tree_root);
-		if (ret < 0) {
-			printk(KERN_WARNING
-			       "btrfs: failed to recover relocation\n");
-			err = -EINVAL;
-			goto fail_trans_kthread;
-		}
-	}
-
-	location.objectid = BTRFS_FS_TREE_OBJECTID;
-	location.type = BTRFS_ROOT_ITEM_KEY;
-	location.offset = (u64)-1;
-
-	fs_info->fs_root = btrfs_read_fs_root_no_name(fs_info, &location);
-	if (!fs_info->fs_root)
-		goto fail_trans_kthread;
-	if (IS_ERR(fs_info->fs_root)) {
-		err = PTR_ERR(fs_info->fs_root);
-		goto fail_trans_kthread;
-	}
-
-	if (!(sb->s_flags & MS_RDONLY)) {
-		down_read(&fs_info->cleanup_work_sem);
-		err = btrfs_orphan_cleanup(fs_info->fs_root);
-		if (!err)
-			err = btrfs_orphan_cleanup(fs_info->tree_root);
-		up_read(&fs_info->cleanup_work_sem);
-
-		if (!err)
-			err = btrfs_recover_balance(fs_info->tree_root);
-
-		if (err) {
-			close_ctree(tree_root);
-			return err;
-		}
-	}
-
-	return 0;
-
-fail_trans_kthread:
-	kthread_stop(fs_info->transaction_kthread);
-fail_cleaner:
-	kthread_stop(fs_info->cleaner_kthread);
-
-	/*
-	 * make sure we're done with the btree inode before we stop our
-	 * kthreads
-	 */
-	filemap_write_and_wait(fs_info->btree_inode->i_mapping);
-	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
-
-fail_block_groups:
-	btrfs_free_block_groups(fs_info);
-
-fail_tree_roots:
-	free_root_pointers(fs_info, 1);
-
-fail_sb_buffer:
-	btrfs_stop_workers(&fs_info->generic_worker);
-	btrfs_stop_workers(&fs_info->readahead_workers);
-	btrfs_stop_workers(&fs_info->fixup_workers);
-	btrfs_stop_workers(&fs_info->delalloc_workers);
-	btrfs_stop_workers(&fs_info->workers);
-	btrfs_stop_workers(&fs_info->endio_workers);
-	btrfs_stop_workers(&fs_info->endio_meta_workers);
-	btrfs_stop_workers(&fs_info->endio_meta_write_workers);
-	btrfs_stop_workers(&fs_info->endio_write_workers);
-	btrfs_stop_workers(&fs_info->endio_freespace_worker);
-	btrfs_stop_workers(&fs_info->submit_workers);
-	btrfs_stop_workers(&fs_info->delayed_workers);
-	btrfs_stop_workers(&fs_info->caching_workers);
-fail_alloc:
-fail_iput:
-	btrfs_mapping_tree_free(&fs_info->mapping_tree);
-
-	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
-	iput(fs_info->btree_inode);
-fail_bdi:
-	bdi_destroy(&fs_info->bdi);
-fail_srcu:
-	cleanup_srcu_struct(&fs_info->subvol_srcu);
-fail:
-	btrfs_close_devices(fs_info->fs_devices);
-	return err;
-
-recovery_tree_root:
-	if (!btrfs_test_opt(tree_root, RECOVERY))
-		goto fail_tree_roots;
-
-	free_root_pointers(fs_info, 0);
-
-	/* don't use the log in recovery mode, it won't be valid */
-	btrfs_set_super_log_root(disk_super, 0);
-
-	/* we can't trust the free space cache either */
-	btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
-
-	ret = next_root_backup(fs_info, fs_info->super_copy,
-			       &num_backups_tried, &backup_index);
-	if (ret == -1)
-		goto fail_block_groups;
-	goto retry_root_backup;
-}
-
-static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
-{
-	char b[BDEVNAME_SIZE];
-
-	if (uptodate) {
-		set_buffer_uptodate(bh);
-	} else {
-		printk_ratelimited(KERN_WARNING "lost page write due to "
-					"I/O error on %s\n",
-				       bdevname(bh->b_bdev, b));
-		/* note, we dont' set_buffer_write_io_error because we have
-		 * our own ways of dealing with the IO errors
-		 */
-		clear_buffer_uptodate(bh);
-	}
-	unlock_buffer(bh);
-	put_bh(bh);
-}
-
-struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
-{
-	struct buffer_head *bh;
-	struct buffer_head *latest = NULL;
-	struct btrfs_super_block *super;
-	int i;
-	u64 transid = 0;
-	u64 bytenr;
-
-	/* we would like to check all the supers, but that would make
-	 * a btrfs mount succeed after a mkfs from a different FS.
-	 * So, we need to add a special mount option to scan for
-	 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
-	 */
-	for (i = 0; i < 1; i++) {
-		bytenr = btrfs_sb_offset(i);
-		if (bytenr + 4096 >= i_size_read(bdev->bd_inode))
-			break;
-		bh = __bread(bdev, bytenr / 4096, 4096);
-		if (!bh)
-			continue;
-
-		super = (struct btrfs_super_block *)bh->b_data;
-		if (btrfs_super_bytenr(super) != bytenr ||
-		    strncmp((char *)(&super->magic), BTRFS_MAGIC,
-			    sizeof(super->magic))) {
-			brelse(bh);
-			continue;
-		}
-
-		if (!latest || btrfs_super_generation(super) > transid) {
-			brelse(latest);
-			latest = bh;
-			transid = btrfs_super_generation(super);
-		} else {
-			brelse(bh);
-		}
-	}
-	return latest;
-}
-
-/*
- * this should be called twice, once with wait == 0 and
- * once with wait == 1.  When wait == 0 is done, all the buffer heads
- * we write are pinned.
- *
- * They are released when wait == 1 is done.
- * max_mirrors must be the same for both runs, and it indicates how
- * many supers on this one device should be written.
- *
- * max_mirrors == 0 means to write them all.
- */
-static int write_dev_supers(struct btrfs_device *device,
-			    struct btrfs_super_block *sb,
-			    int do_barriers, int wait, int max_mirrors)
-{
-	struct buffer_head *bh;
-	int i;
-	int ret;
-	int errors = 0;
-	u32 crc;
-	u64 bytenr;
-
-	if (max_mirrors == 0)
-		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
-
-	for (i = 0; i < max_mirrors; i++) {
-		bytenr = btrfs_sb_offset(i);
-		if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->total_bytes)
-			break;
-
-		if (wait) {
-			bh = __find_get_block(device->bdev, bytenr / 4096,
-					      BTRFS_SUPER_INFO_SIZE);
-			BUG_ON(!bh);
-			wait_on_buffer(bh);
-			if (!buffer_uptodate(bh))
-				errors++;
-
-			/* drop our reference */
-			brelse(bh);
-
-			/* drop the reference from the wait == 0 run */
-			brelse(bh);
-			continue;
-		} else {
-			btrfs_set_super_bytenr(sb, bytenr);
-
-			crc = ~(u32)0;
-			crc = btrfs_csum_data(NULL, (char *)sb +
-					      BTRFS_CSUM_SIZE, crc,
-					      BTRFS_SUPER_INFO_SIZE -
-					      BTRFS_CSUM_SIZE);
-			btrfs_csum_final(crc, sb->csum);
-
-			/*
-			 * one reference for us, and we leave it for the
-			 * caller
-			 */
-			bh = __getblk(device->bdev, bytenr / 4096,
-				      BTRFS_SUPER_INFO_SIZE);
-			memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
-
-			/* one reference for submit_bh */
-			get_bh(bh);
-
-			set_buffer_uptodate(bh);
-			lock_buffer(bh);
-			bh->b_end_io = btrfs_end_buffer_write_sync;
-		}
-
-		/*
-		 * we fua the first super.  The others we allow
-		 * to go down lazy.
-		 */
-		ret = btrfsic_submit_bh(WRITE_FUA, bh);
-		if (ret)
-			errors++;
-	}
-	return errors < i ? 0 : -1;
-}
-
-/*
- * endio for the write_dev_flush, this will wake anyone waiting
- * for the barrier when it is done
- */
-static void btrfs_end_empty_barrier(struct bio *bio, int err)
-{
-	if (err) {
-		if (err == -EOPNOTSUPP)
-			set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
-		clear_bit(BIO_UPTODATE, &bio->bi_flags);
-	}
-	if (bio->bi_private)
-		complete(bio->bi_private);
-	bio_put(bio);
-}
-
-/*
- * trigger flushes for one the devices.  If you pass wait == 0, the flushes are
- * sent down.  With wait == 1, it waits for the previous flush.
- *
- * any device where the flush fails with eopnotsupp are flagged as not-barrier
- * capable
- */
-static int write_dev_flush(struct btrfs_device *device, int wait)
-{
-	struct bio *bio;
-	int ret = 0;
-
-	if (device->nobarriers)
-		return 0;
-
-	if (wait) {
-		bio = device->flush_bio;
-		if (!bio)
-			return 0;
-
-		wait_for_completion(&device->flush_wait);
-
-		if (bio_flagged(bio, BIO_EOPNOTSUPP)) {
-			printk("btrfs: disabling barriers on dev %s\n",
-			       device->name);
-			device->nobarriers = 1;
-		}
-		if (!bio_flagged(bio, BIO_UPTODATE)) {
-			ret = -EIO;
-		}
-
-		/* drop the reference from the wait == 0 run */
-		bio_put(bio);
-		device->flush_bio = NULL;
-
-		return ret;
-	}
-
-	/*
-	 * one reference for us, and we leave it for the
-	 * caller
-	 */
-	device->flush_bio = NULL;;
-	bio = bio_alloc(GFP_NOFS, 0);
-	if (!bio)
-		return -ENOMEM;
-
-	bio->bi_end_io = btrfs_end_empty_barrier;
-	bio->bi_bdev = device->bdev;
-	init_completion(&device->flush_wait);
-	bio->bi_private = &device->flush_wait;
-	device->flush_bio = bio;
-
-	bio_get(bio);
-	btrfsic_submit_bio(WRITE_FLUSH, bio);
-
-	return 0;
-}
-
-/*
- * send an empty flush down to each device in parallel,
- * then wait for them
- */
-static int barrier_all_devices(struct btrfs_fs_info *info)
-{
-	struct list_head *head;
-	struct btrfs_device *dev;
-	int errors = 0;
-	int ret;
-
-	/* send down all the barriers */
-	head = &info->fs_devices->devices;
-	list_for_each_entry_rcu(dev, head, dev_list) {
-		if (!dev->bdev) {
-			errors++;
-			continue;
-		}
-		if (!dev->in_fs_metadata || !dev->writeable)
-			continue;
-
-		ret = write_dev_flush(dev, 0);
-		if (ret)
-			errors++;
-	}
-
-	/* wait for all the barriers */
-	list_for_each_entry_rcu(dev, head, dev_list) {
-		if (!dev->bdev) {
-			errors++;
-			continue;
-		}
-		if (!dev->in_fs_metadata || !dev->writeable)
-			continue;
-
-		ret = write_dev_flush(dev, 1);
-		if (ret)
-			errors++;
-	}
-	if (errors)
-		return -EIO;
-	return 0;
-}
-
-int write_all_supers(struct btrfs_root *root, int max_mirrors)
-{
-	struct list_head *head;
-	struct btrfs_device *dev;
-	struct btrfs_super_block *sb;
-	struct btrfs_dev_item *dev_item;
-	int ret;
-	int do_barriers;
-	int max_errors;
-	int total_errors = 0;
-	u64 flags;
-
-	max_errors = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
-	do_barriers = !btrfs_test_opt(root, NOBARRIER);
-	backup_super_roots(root->fs_info);
-
-	sb = root->fs_info->super_for_commit;
-	dev_item = &sb->dev_item;
-
-	mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
-	head = &root->fs_info->fs_devices->devices;
-
-	if (do_barriers)
-		barrier_all_devices(root->fs_info);
-
-	list_for_each_entry_rcu(dev, head, dev_list) {
-		if (!dev->bdev) {
-			total_errors++;
-			continue;
-		}
-		if (!dev->in_fs_metadata || !dev->writeable)
-			continue;
-
-		btrfs_set_stack_device_generation(dev_item, 0);
-		btrfs_set_stack_device_type(dev_item, dev->type);
-		btrfs_set_stack_device_id(dev_item, dev->devid);
-		btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
-		btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
-		btrfs_set_stack_device_io_align(dev_item, dev->io_align);
-		btrfs_set_stack_device_io_width(dev_item, dev->io_width);
-		btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
-		memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
-		memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
-
-		flags = btrfs_super_flags(sb);
-		btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
-
-		ret = write_dev_supers(dev, sb, do_barriers, 0, max_mirrors);
-		if (ret)
-			total_errors++;
-	}
-	if (total_errors > max_errors) {
-		printk(KERN_ERR "btrfs: %d errors while writing supers\n",
-		       total_errors);
-
-		/* This shouldn't happen. FUA is masked off if unsupported */
-		BUG();
-	}
-
-	total_errors = 0;
-	list_for_each_entry_rcu(dev, head, dev_list) {
-		if (!dev->bdev)
-			continue;
-		if (!dev->in_fs_metadata || !dev->writeable)
-			continue;
-
-		ret = write_dev_supers(dev, sb, do_barriers, 1, max_mirrors);
-		if (ret)
-			total_errors++;
-	}
-	mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
-	if (total_errors > max_errors) {
-		btrfs_error(root->fs_info, -EIO,
-			    "%d errors while writing supers", total_errors);
-		return -EIO;
-	}
-	return 0;
-}
-
-int write_ctree_super(struct btrfs_trans_handle *trans,
-		      struct btrfs_root *root, int max_mirrors)
-{
-	int ret;
-
-	ret = write_all_supers(root, max_mirrors);
-	return ret;
-}
-
-/* Kill all outstanding I/O */
-void btrfs_abort_devices(struct btrfs_root *root)
-{
-	struct list_head *head;
-	struct btrfs_device *dev;
-	mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
-	head = &root->fs_info->fs_devices->devices;
-	list_for_each_entry_rcu(dev, head, dev_list) {
-		blk_abort_queue(dev->bdev->bd_disk->queue);
-	}
-	mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
-}
-
-void btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
-{
-	spin_lock(&fs_info->fs_roots_radix_lock);
-	radix_tree_delete(&fs_info->fs_roots_radix,
-			  (unsigned long)root->root_key.objectid);
-	spin_unlock(&fs_info->fs_roots_radix_lock);
-
-	if (btrfs_root_refs(&root->root_item) == 0)
-		synchronize_srcu(&fs_info->subvol_srcu);
-
-	__btrfs_remove_free_space_cache(root->free_ino_pinned);
-	__btrfs_remove_free_space_cache(root->free_ino_ctl);
-	free_fs_root(root);
-}
-
-static void free_fs_root(struct btrfs_root *root)
-{
-	iput(root->cache_inode);
-	WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
-	if (root->anon_dev)
-		free_anon_bdev(root->anon_dev);
-	free_extent_buffer(root->node);
-	free_extent_buffer(root->commit_root);
-	kfree(root->free_ino_ctl);
-	kfree(root->free_ino_pinned);
-	kfree(root->name);
-	kfree(root);
-}
-
-static void del_fs_roots(struct btrfs_fs_info *fs_info)
-{
-	int ret;
-	struct btrfs_root *gang[8];
-	int i;
-
-	while (!list_empty(&fs_info->dead_roots)) {
-		gang[0] = list_entry(fs_info->dead_roots.next,
-				     struct btrfs_root, root_list);
-		list_del(&gang[0]->root_list);
-
-		if (gang[0]->in_radix) {
-			btrfs_free_fs_root(fs_info, gang[0]);
-		} else {
-			free_extent_buffer(gang[0]->node);
-			free_extent_buffer(gang[0]->commit_root);
-			kfree(gang[0]);
-		}
-	}
-
-	while (1) {
-		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
-					     (void **)gang, 0,
-					     ARRAY_SIZE(gang));
-		if (!ret)
-			break;
-		for (i = 0; i < ret; i++)
-			btrfs_free_fs_root(fs_info, gang[i]);
-	}
-}
-
-int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
-{
-	u64 root_objectid = 0;
-	struct btrfs_root *gang[8];
-	int i;
-	int ret;
-
-	while (1) {
-		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
-					     (void **)gang, root_objectid,
-					     ARRAY_SIZE(gang));
-		if (!ret)
-			break;
-
-		root_objectid = gang[ret - 1]->root_key.objectid + 1;
-		for (i = 0; i < ret; i++) {
-			int err;
-
-			root_objectid = gang[i]->root_key.objectid;
-			err = btrfs_orphan_cleanup(gang[i]);
-			if (err)
-				return err;
-		}
-		root_objectid++;
-	}
-	return 0;
-}
-
-int btrfs_commit_super(struct btrfs_root *root)
-{
-	struct btrfs_trans_handle *trans;
-	int ret;
-
-	mutex_lock(&root->fs_info->cleaner_mutex);
-	btrfs_run_delayed_iputs(root);
-	btrfs_clean_old_snapshots(root);
-	mutex_unlock(&root->fs_info->cleaner_mutex);
-
-	/* wait until ongoing cleanup work done */
-	down_write(&root->fs_info->cleanup_work_sem);
-	up_write(&root->fs_info->cleanup_work_sem);
-
-	trans = btrfs_join_transaction(root);
-	if (IS_ERR(trans))
-		return PTR_ERR(trans);
-	ret = btrfs_commit_transaction(trans, root);
-	if (ret)
-		return ret;
-	/* run commit again to drop the original snapshot */
-	trans = btrfs_join_transaction(root);
-	if (IS_ERR(trans))
-		return PTR_ERR(trans);
-	ret = btrfs_commit_transaction(trans, root);
-	if (ret)
-		return ret;
-	ret = btrfs_write_and_wait_transaction(NULL, root);
-	if (ret) {
-		btrfs_error(root->fs_info, ret,
-			    "Failed to sync btree inode to disk.");
-		return ret;
-	}
-
-	ret = write_ctree_super(NULL, root, 0);
-	return ret;
-}
-
-int close_ctree(struct btrfs_root *root)
-{
-	struct btrfs_fs_info *fs_info = root->fs_info;
-	int ret;
-
-	fs_info->closing = 1;
-	smp_mb();
-
-	/* pause restriper - we want to resume on mount */
-	btrfs_pause_balance(root->fs_info);
-
-	btrfs_scrub_cancel(root);
-
-	/* wait for any defraggers to finish */
-	wait_event(fs_info->transaction_wait,
-		   (atomic_read(&fs_info->defrag_running) == 0));
-
-	/* clear out the rbtree of defraggable inodes */
-	btrfs_run_defrag_inodes(fs_info);
-
-	/*
-	 * Here come 2 situations when btrfs is broken to flip readonly:
-	 *
-	 * 1. when btrfs flips readonly somewhere else before
-	 * btrfs_commit_super, sb->s_flags has MS_RDONLY flag,
-	 * and btrfs will skip to write sb directly to keep
-	 * ERROR state on disk.
-	 *
-	 * 2. when btrfs flips readonly just in btrfs_commit_super,
-	 * and in such case, btrfs cannot write sb via btrfs_commit_super,
-	 * and since fs_state has been set BTRFS_SUPER_FLAG_ERROR flag,
-	 * btrfs will cleanup all FS resources first and write sb then.
-	 */
-	if (!(fs_info->sb->s_flags & MS_RDONLY)) {
-		ret = btrfs_commit_super(root);
-		if (ret)
-			printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
-	}
-
-	if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
-		ret = btrfs_error_commit_super(root);
-		if (ret)
-			printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
-	}
-
-	btrfs_put_block_group_cache(fs_info);
-
-	kthread_stop(fs_info->transaction_kthread);
-	kthread_stop(fs_info->cleaner_kthread);
-
-	fs_info->closing = 2;
-	smp_mb();
-
-	if (fs_info->delalloc_bytes) {
-		printk(KERN_INFO "btrfs: at unmount delalloc count %llu\n",
-		       (unsigned long long)fs_info->delalloc_bytes);
-	}
-	if (fs_info->total_ref_cache_size) {
-		printk(KERN_INFO "btrfs: at umount reference cache size %llu\n",
-		       (unsigned long long)fs_info->total_ref_cache_size);
-	}
-
-	free_extent_buffer(fs_info->extent_root->node);
-	free_extent_buffer(fs_info->extent_root->commit_root);
-	free_extent_buffer(fs_info->tree_root->node);
-	free_extent_buffer(fs_info->tree_root->commit_root);
-	free_extent_buffer(fs_info->chunk_root->node);
-	free_extent_buffer(fs_info->chunk_root->commit_root);
-	free_extent_buffer(fs_info->dev_root->node);
-	free_extent_buffer(fs_info->dev_root->commit_root);
-	free_extent_buffer(fs_info->csum_root->node);
-	free_extent_buffer(fs_info->csum_root->commit_root);
-
-	btrfs_free_block_groups(fs_info);
-
-	del_fs_roots(fs_info);
-
-	iput(fs_info->btree_inode);
-
-	btrfs_stop_workers(&fs_info->generic_worker);
-	btrfs_stop_workers(&fs_info->fixup_workers);
-	btrfs_stop_workers(&fs_info->delalloc_workers);
-	btrfs_stop_workers(&fs_info->workers);
-	btrfs_stop_workers(&fs_info->endio_workers);
-	btrfs_stop_workers(&fs_info->endio_meta_workers);
-	btrfs_stop_workers(&fs_info->endio_meta_write_workers);
-	btrfs_stop_workers(&fs_info->endio_write_workers);
-	btrfs_stop_workers(&fs_info->endio_freespace_worker);
-	btrfs_stop_workers(&fs_info->submit_workers);
-	btrfs_stop_workers(&fs_info->delayed_workers);
-	btrfs_stop_workers(&fs_info->caching_workers);
-	btrfs_stop_workers(&fs_info->readahead_workers);
-
-#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
-	if (btrfs_test_opt(root, CHECK_INTEGRITY))
-		btrfsic_unmount(root, fs_info->fs_devices);
-#endif
-
-	btrfs_close_devices(fs_info->fs_devices);
-	btrfs_mapping_tree_free(&fs_info->mapping_tree);
-
-	bdi_destroy(&fs_info->bdi);
-	cleanup_srcu_struct(&fs_info->subvol_srcu);
-
-	return 0;
-}
-
-int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
-			  int atomic)
-{
-	int ret;
-	struct inode *btree_inode = buf->pages[0]->mapping->host;
-
-	ret = extent_buffer_uptodate(buf);
-	if (!ret)
-		return ret;
-
-	ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
-				    parent_transid, atomic);
-	if (ret == -EAGAIN)
-		return ret;
-	return !ret;
-}
-
-int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
-{
-	return set_extent_buffer_uptodate(buf);
-}
-
-void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
-{
-	struct btrfs_root *root = BTRFS_I(buf->pages[0]->mapping->host)->root;
-	u64 transid = btrfs_header_generation(buf);
-	int was_dirty;
-
-	btrfs_assert_tree_locked(buf);
-	if (transid != root->fs_info->generation) {
-		printk(KERN_CRIT "btrfs transid mismatch buffer %llu, "
-		       "found %llu running %llu\n",
-			(unsigned long long)buf->start,
-			(unsigned long long)transid,
-			(unsigned long long)root->fs_info->generation);
-		WARN_ON(1);
-	}
-	was_dirty = set_extent_buffer_dirty(buf);
-	if (!was_dirty) {
-		spin_lock(&root->fs_info->delalloc_lock);
-		root->fs_info->dirty_metadata_bytes += buf->len;
-		spin_unlock(&root->fs_info->delalloc_lock);
-	}
-}
-
-void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
-{
-	/*
-	 * looks as though older kernels can get into trouble with
-	 * this code, they end up stuck in balance_dirty_pages forever
-	 */
-	u64 num_dirty;
-	unsigned long thresh = 32 * 1024 * 1024;
-
-	if (current->flags & PF_MEMALLOC)
-		return;
-
-	btrfs_balance_delayed_items(root);
-
-	num_dirty = root->fs_info->dirty_metadata_bytes;
-
-	if (num_dirty > thresh) {
-		balance_dirty_pages_ratelimited_nr(
-				   root->fs_info->btree_inode->i_mapping, 1);
-	}
-	return;
-}
-
-void __btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
-{
-	/*
-	 * looks as though older kernels can get into trouble with
-	 * this code, they end up stuck in balance_dirty_pages forever
-	 */
-	u64 num_dirty;
-	unsigned long thresh = 32 * 1024 * 1024;
-
-	if (current->flags & PF_MEMALLOC)
-		return;
-
-	num_dirty = root->fs_info->dirty_metadata_bytes;
-
-	if (num_dirty > thresh) {
-		balance_dirty_pages_ratelimited_nr(
-				   root->fs_info->btree_inode->i_mapping, 1);
-	}
-	return;
-}
-
-int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
-{
-	struct btrfs_root *root = BTRFS_I(buf->pages[0]->mapping->host)->root;
-	return btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
-}
-
-static int btree_lock_page_hook(struct page *page, void *data,
-				void (*flush_fn)(void *))
-{
-	struct inode *inode = page->mapping->host;
-	struct btrfs_root *root = BTRFS_I(inode)->root;
-	struct extent_buffer *eb;
-
-	/*
-	 * We culled this eb but the page is still hanging out on the mapping,
-	 * carry on.
-	 */
-	if (!PagePrivate(page))
-		goto out;
-
-	eb = (struct extent_buffer *)page->private;
-	if (!eb) {
-		WARN_ON(1);
-		goto out;
-	}
-	if (page != eb->pages[0])
-		goto out;
-
-	if (!btrfs_try_tree_write_lock(eb)) {
-		flush_fn(data);
-		btrfs_tree_lock(eb);
-	}
-	btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
-
-	if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
-		spin_lock(&root->fs_info->delalloc_lock);
-		if (root->fs_info->dirty_metadata_bytes >= eb->len)
-			root->fs_info->dirty_metadata_bytes -= eb->len;
-		else
-			WARN_ON(1);
-		spin_unlock(&root->fs_info->delalloc_lock);
-	}
-
-	btrfs_tree_unlock(eb);
-out:
-	if (!trylock_page(page)) {
-		flush_fn(data);
-		lock_page(page);
-	}
-	return 0;
-}
-
-static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
-			      int read_only)
-{
-	if (btrfs_super_csum_type(fs_info->super_copy) >= ARRAY_SIZE(btrfs_csum_sizes)) {
-		printk(KERN_ERR "btrfs: unsupported checksum algorithm\n");
-		return -EINVAL;
-	}
-
-	if (read_only)
-		return 0;
-
-	if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
-		printk(KERN_WARNING "warning: mount fs with errors, "
-		       "running btrfsck is recommended\n");
-	}
-
-	return 0;
-}
-
-int btrfs_error_commit_super(struct btrfs_root *root)
-{
-	int ret;
-
-	mutex_lock(&root->fs_info->cleaner_mutex);
-	btrfs_run_delayed_iputs(root);
-	mutex_unlock(&root->fs_info->cleaner_mutex);
-
-	down_write(&root->fs_info->cleanup_work_sem);
-	up_write(&root->fs_info->cleanup_work_sem);
-
-	/* cleanup FS via transaction */
-	btrfs_cleanup_transaction(root);
-
-	ret = write_ctree_super(NULL, root, 0);
-
-	return ret;
-}
-
-static void btrfs_destroy_ordered_operations(struct btrfs_root *root)
-{
-	struct btrfs_inode *btrfs_inode;
-	struct list_head splice;
-
-	INIT_LIST_HEAD(&splice);
-
-	mutex_lock(&root->fs_info->ordered_operations_mutex);
-	spin_lock(&root->fs_info->ordered_extent_lock);
-
-	list_splice_init(&root->fs_info->ordered_operations, &splice);
-	while (!list_empty(&splice)) {
-		btrfs_inode = list_entry(splice.next, struct btrfs_inode,
-					 ordered_operations);
-
-		list_del_init(&btrfs_inode->ordered_operations);
-
-		btrfs_invalidate_inodes(btrfs_inode->root);
-	}
-
-	spin_unlock(&root->fs_info->ordered_extent_lock);
-	mutex_unlock(&root->fs_info->ordered_operations_mutex);
-}
-
-static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
-{
-	struct list_head splice;
-	struct btrfs_ordered_extent *ordered;
-	struct inode *inode;
-
-	INIT_LIST_HEAD(&splice);
-
-	spin_lock(&root->fs_info->ordered_extent_lock);
-
-	list_splice_init(&root->fs_info->ordered_extents, &splice);
-	while (!list_empty(&splice)) {
-		ordered = list_entry(splice.next, struct btrfs_ordered_extent,
-				     root_extent_list);
-
-		list_del_init(&ordered->root_extent_list);
-		atomic_inc(&ordered->refs);
-
-		/* the inode may be getting freed (in sys_unlink path). */
-		inode = igrab(ordered->inode);
-
-		spin_unlock(&root->fs_info->ordered_extent_lock);
-		if (inode)
-			iput(inode);
-
-		atomic_set(&ordered->refs, 1);
-		btrfs_put_ordered_extent(ordered);
-
-		spin_lock(&root->fs_info->ordered_extent_lock);
-	}
-
-	spin_unlock(&root->fs_info->ordered_extent_lock);
-}
-
-int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
-			       struct btrfs_root *root)
-{
-	struct rb_node *node;
-	struct btrfs_delayed_ref_root *delayed_refs;
-	struct btrfs_delayed_ref_node *ref;
-	int ret = 0;
-
-	delayed_refs = &trans->delayed_refs;
-
-again:
-	spin_lock(&delayed_refs->lock);
-	if (delayed_refs->num_entries == 0) {
-		spin_unlock(&delayed_refs->lock);
-		printk(KERN_INFO "delayed_refs has NO entry\n");
-		return ret;
-	}
-
-	node = rb_first(&delayed_refs->root);
-	while (node) {
-		ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
-		node = rb_next(node);
-
-		ref->in_tree = 0;
-		rb_erase(&ref->rb_node, &delayed_refs->root);
-		delayed_refs->num_entries--;
-
-		atomic_set(&ref->refs, 1);
-		if (btrfs_delayed_ref_is_head(ref)) {
-			struct btrfs_delayed_ref_head *head;
-
-			head = btrfs_delayed_node_to_head(ref);
-			spin_unlock(&delayed_refs->lock);
-			mutex_lock(&head->mutex);
-			kfree(head->extent_op);
-			delayed_refs->num_heads--;
-			if (list_empty(&head->cluster))
-				delayed_refs->num_heads_ready--;
-			list_del_init(&head->cluster);
-			mutex_unlock(&head->mutex);
-			btrfs_put_delayed_ref(ref);
-			goto again;
-		}
-		spin_unlock(&delayed_refs->lock);
-		btrfs_put_delayed_ref(ref);
-
-		cond_resched();
-		spin_lock(&delayed_refs->lock);
-	}
-
-	spin_unlock(&delayed_refs->lock);
-
-	return ret;
-}
-
-static void btrfs_destroy_pending_snapshots(struct btrfs_transaction *t)
-{
-	struct btrfs_pending_snapshot *snapshot;
-	struct list_head splice;
-
-	INIT_LIST_HEAD(&splice);
-
-	list_splice_init(&t->pending_snapshots, &splice);
-
-	while (!list_empty(&splice)) {
-		snapshot = list_entry(splice.next,
-				      struct btrfs_pending_snapshot,
-				      list);
-
-		list_del_init(&snapshot->list);
-
-		kfree(snapshot);
-	}
-}
-
-static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
-{
-	struct btrfs_inode *btrfs_inode;
-	struct list_head splice;
-
-	INIT_LIST_HEAD(&splice);
-
-	spin_lock(&root->fs_info->delalloc_lock);
-	list_splice_init(&root->fs_info->delalloc_inodes, &splice);
-
-	while (!list_empty(&splice)) {
-		btrfs_inode = list_entry(splice.next, struct btrfs_inode,
-				    delalloc_inodes);
-
-		list_del_init(&btrfs_inode->delalloc_inodes);
-
-		btrfs_invalidate_inodes(btrfs_inode->root);
-	}
-
-	spin_unlock(&root->fs_info->delalloc_lock);
-}
-
-static int btrfs_destroy_marked_extents(struct btrfs_root *root,
-					struct extent_io_tree *dirty_pages,
-					int mark)
-{
-	int ret;
-	struct page *page;
-	struct inode *btree_inode = root->fs_info->btree_inode;
-	struct extent_buffer *eb;
-	u64 start = 0;
-	u64 end;
-	u64 offset;
-	unsigned long index;
-
-	while (1) {
-		ret = find_first_extent_bit(dirty_pages, start, &start, &end,
-					    mark);
-		if (ret)
-			break;
-
-		clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS);
-		while (start <= end) {
-			index = start >> PAGE_CACHE_SHIFT;
-			start = (u64)(index + 1) << PAGE_CACHE_SHIFT;
-			page = find_get_page(btree_inode->i_mapping, index);
-			if (!page)
-				continue;
-			offset = page_offset(page);
-
-			spin_lock(&dirty_pages->buffer_lock);
-			eb = radix_tree_lookup(
-			     &(&BTRFS_I(page->mapping->host)->io_tree)->buffer,
-					       offset >> PAGE_CACHE_SHIFT);
-			spin_unlock(&dirty_pages->buffer_lock);
-			if (eb) {
-				ret = test_and_clear_bit(EXTENT_BUFFER_DIRTY,
-							 &eb->bflags);
-				atomic_set(&eb->refs, 1);
-			}
-			if (PageWriteback(page))
-				end_page_writeback(page);
-
-			lock_page(page);
-			if (PageDirty(page)) {
-				clear_page_dirty_for_io(page);
-				spin_lock_irq(&page->mapping->tree_lock);
-				radix_tree_tag_clear(&page->mapping->page_tree,
-							page_index(page),
-							PAGECACHE_TAG_DIRTY);
-				spin_unlock_irq(&page->mapping->tree_lock);
-			}
-
-			page->mapping->a_ops->invalidatepage(page, 0);
-			unlock_page(page);
-		}
-	}
-
-	return ret;
-}
-
-static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
-				       struct extent_io_tree *pinned_extents)
-{
-	struct extent_io_tree *unpin;
-	u64 start;
-	u64 end;
-	int ret;
-
-	unpin = pinned_extents;
-	while (1) {
-		ret = find_first_extent_bit(unpin, 0, &start, &end,
-					    EXTENT_DIRTY);
-		if (ret)
-			break;
-
-		/* opt_discard */
-		if (btrfs_test_opt(root, DISCARD))
-			ret = btrfs_error_discard_extent(root, start,
-							 end + 1 - start,
-							 NULL);
-
-		clear_extent_dirty(unpin, start, end, GFP_NOFS);
-		btrfs_error_unpin_extent_range(root, start, end);
-		cond_resched();
-	}
-
-	return 0;
-}
-
-void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
-				   struct btrfs_root *root)
-{
-	btrfs_destroy_delayed_refs(cur_trans, root);
-	btrfs_block_rsv_release(root, &root->fs_info->trans_block_rsv,
-				cur_trans->dirty_pages.dirty_bytes);
-
-	/* FIXME: cleanup wait for commit */
-	cur_trans->in_commit = 1;
-	cur_trans->blocked = 1;
-	if (waitqueue_active(&root->fs_info->transaction_blocked_wait))
-		wake_up(&root->fs_info->transaction_blocked_wait);
-
-	cur_trans->blocked = 0;
-	if (waitqueue_active(&root->fs_info->transaction_wait))
-		wake_up(&root->fs_info->transaction_wait);
-
-	cur_trans->commit_done = 1;
-	if (waitqueue_active(&cur_trans->commit_wait))
-		wake_up(&cur_trans->commit_wait);
-
-	btrfs_destroy_pending_snapshots(cur_trans);
-
-	btrfs_destroy_marked_extents(root, &cur_trans->dirty_pages,
-				     EXTENT_DIRTY);
-
-	/*
-	memset(cur_trans, 0, sizeof(*cur_trans));
-	kmem_cache_free(btrfs_transaction_cachep, cur_trans);
-	*/
-}
-
-int btrfs_cleanup_transaction(struct btrfs_root *root)
-{
-	struct btrfs_transaction *t;
-	LIST_HEAD(list);
-
-	mutex_lock(&root->fs_info->transaction_kthread_mutex);
-
-	spin_lock(&root->fs_info->trans_lock);
-	list_splice_init(&root->fs_info->trans_list, &list);
-	root->fs_info->trans_no_join = 1;
-	spin_unlock(&root->fs_info->trans_lock);
-
-	while (!list_empty(&list)) {
-		t = list_entry(list.next, struct btrfs_transaction, list);
-		if (!t)
-			break;
-
-		btrfs_destroy_ordered_operations(root);
-
-		btrfs_destroy_ordered_extents(root);
-
-		btrfs_destroy_delayed_refs(t, root);
-
-		btrfs_block_rsv_release(root,
-					&root->fs_info->trans_block_rsv,
-					t->dirty_pages.dirty_bytes);
-
-		/* FIXME: cleanup wait for commit */
-		t->in_commit = 1;
-		t->blocked = 1;
-		if (waitqueue_active(&root->fs_info->transaction_blocked_wait))
-			wake_up(&root->fs_info->transaction_blocked_wait);
-
-		t->blocked = 0;
-		if (waitqueue_active(&root->fs_info->transaction_wait))
-			wake_up(&root->fs_info->transaction_wait);
-
-		t->commit_done = 1;
-		if (waitqueue_active(&t->commit_wait))
-			wake_up(&t->commit_wait);
-
-		btrfs_destroy_pending_snapshots(t);
-
-		btrfs_destroy_delalloc_inodes(root);
-
-		spin_lock(&root->fs_info->trans_lock);
-		root->fs_info->running_transaction = NULL;
-		spin_unlock(&root->fs_info->trans_lock);
-
-		btrfs_destroy_marked_extents(root, &t->dirty_pages,
-					     EXTENT_DIRTY);
-
-		btrfs_destroy_pinned_extent(root,
-					    root->fs_info->pinned_extents);
-
-		atomic_set(&t->use_count, 0);
-		list_del_init(&t->list);
-		memset(t, 0, sizeof(*t));
-		kmem_cache_free(btrfs_transaction_cachep, t);
-	}
-
-	spin_lock(&root->fs_info->trans_lock);
-	root->fs_info->trans_no_join = 0;
-	spin_unlock(&root->fs_info->trans_lock);
-	mutex_unlock(&root->fs_info->transaction_kthread_mutex);
-
-	return 0;
-}
-
-static int btree_writepage_io_failed_hook(struct bio *bio, struct page *page,
-					  u64 start, u64 end,
-					  struct extent_state *state)
-{
-	struct super_block *sb = page->mapping->host->i_sb;
-	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
-	btrfs_error(fs_info, -EIO,
-		    "Error occured while writing out btree at %llu", start);
-	return -EIO;
-}
-
-static struct extent_io_ops btree_extent_io_ops = {
-	.write_cache_pages_lock_hook = btree_lock_page_hook,
-	.readpage_end_io_hook = btree_readpage_end_io_hook,
-	.readpage_io_failed_hook = btree_io_failed_hook,
-	.submit_bio_hook = btree_submit_bio_hook,
-	/* note we're sharing with inode.c for the merge bio hook */
-	.merge_bio_hook = btrfs_merge_bio_hook,
-	.writepage_io_failed_hook = btree_writepage_io_failed_hook,
-};