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#include <linux/module.h>
#include <linux/fs.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
static int check_tree_block(struct btrfs_root *root, struct buffer_head *buf)
{
struct btrfs_node *node = btrfs_buffer_node(buf);
if (buf->b_blocknr != btrfs_header_blocknr(&node->header))
BUG();
if (root->node && btrfs_header_parentid(&node->header) !=
btrfs_header_parentid(btrfs_buffer_header(root->node))) {
BUG();
}
return 0;
}
struct buffer_head *alloc_tree_block(struct btrfs_root *root, u64 blocknr)
{
return sb_getblk(root->fs_info->sb, blocknr);
}
struct buffer_head *find_tree_block(struct btrfs_root *root, u64 blocknr)
{
return sb_getblk(root->fs_info->sb, blocknr);
}
struct buffer_head *read_tree_block(struct btrfs_root *root, u64 blocknr)
{
struct buffer_head *buf = sb_bread(root->fs_info->sb, blocknr);
if (!buf)
return buf;
if (check_tree_block(root, buf))
BUG();
return buf;
}
int dirty_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct buffer_head *buf)
{
mark_buffer_dirty(buf);
return 0;
}
int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct buffer_head *buf)
{
clear_buffer_dirty(buf);
return 0;
}
static int __setup_root(struct btrfs_super_block *super,
struct btrfs_root *root,
struct btrfs_fs_info *fs_info,
u64 objectid)
{
root->node = NULL;
root->commit_root = NULL;
root->blocksize = btrfs_super_blocksize(super);
root->ref_cows = 0;
root->fs_info = fs_info;
memset(&root->root_key, 0, sizeof(root->root_key));
memset(&root->root_item, 0, sizeof(root->root_item));
return 0;
}
static int find_and_setup_root(struct btrfs_super_block *super,
struct btrfs_root *tree_root,
struct btrfs_fs_info *fs_info,
u64 objectid,
struct btrfs_root *root)
{
int ret;
__setup_root(super, root, fs_info, objectid);
ret = btrfs_find_last_root(tree_root, objectid,
&root->root_item, &root->root_key);
BUG_ON(ret);
root->node = read_tree_block(root,
btrfs_root_blocknr(&root->root_item));
BUG_ON(!root->node);
return 0;
}
struct btrfs_root *open_ctree(struct super_block *sb,
struct buffer_head *sb_buffer,
struct btrfs_super_block *disk_super)
{
struct btrfs_root *root = kmalloc(sizeof(struct btrfs_root),
GFP_NOFS);
struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root),
GFP_NOFS);
struct btrfs_root *tree_root = kmalloc(sizeof(struct btrfs_root),
GFP_NOFS);
struct btrfs_root *inode_root = kmalloc(sizeof(struct btrfs_root),
GFP_NOFS);
struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info),
GFP_NOFS);
int ret;
/* FIXME: don't be stupid */
if (!btrfs_super_root(disk_super))
return NULL;
INIT_RADIX_TREE(&fs_info->pinned_radix, GFP_KERNEL);
fs_info->running_transaction = NULL;
fs_info->fs_root = root;
fs_info->tree_root = tree_root;
fs_info->extent_root = extent_root;
fs_info->inode_root = inode_root;
fs_info->last_inode_alloc = 0;
fs_info->last_inode_alloc_dirid = 0;
fs_info->disk_super = disk_super;
fs_info->sb_buffer = sb_buffer;
fs_info->sb = sb;
mutex_init(&fs_info->trans_mutex);
mutex_init(&fs_info->fs_mutex);
memset(&fs_info->current_insert, 0, sizeof(fs_info->current_insert));
memset(&fs_info->last_insert, 0, sizeof(fs_info->last_insert));
__setup_root(disk_super, tree_root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
tree_root->node = read_tree_block(tree_root,
btrfs_super_root(disk_super));
BUG_ON(!tree_root->node);
ret = find_and_setup_root(disk_super, tree_root, fs_info,
BTRFS_EXTENT_TREE_OBJECTID, extent_root);
BUG_ON(ret);
ret = find_and_setup_root(disk_super, tree_root, fs_info,
BTRFS_INODE_MAP_OBJECTID, inode_root);
BUG_ON(ret);
ret = find_and_setup_root(disk_super, tree_root, fs_info,
BTRFS_FS_TREE_OBJECTID, root);
BUG_ON(ret);
root->commit_root = root->node;
get_bh(root->node);
root->ref_cows = 1;
root->fs_info->generation = root->root_key.offset + 1;
return root;
}
int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
*root)
{
struct buffer_head *bh = root->fs_info->sb_buffer;
btrfs_set_super_root(root->fs_info->disk_super,
root->fs_info->tree_root->node->b_blocknr);
lock_buffer(bh);
clear_buffer_dirty(bh);
bh->b_end_io = end_buffer_write_sync;
get_bh(bh);
submit_bh(WRITE, bh);
wait_on_buffer(bh);
if (!buffer_uptodate(bh)) {
WARN_ON(1);
return -EIO;
}
return 0;
}
int close_ctree(struct btrfs_root *root)
{
int ret;
struct btrfs_trans_handle *trans;
trans = btrfs_start_transaction(root, 1);
btrfs_commit_transaction(trans, root);
/* run commit again to drop the original snapshot */
trans = btrfs_start_transaction(root, 1);
btrfs_commit_transaction(trans, root);
ret = btrfs_write_and_wait_transaction(NULL, root);
BUG_ON(ret);
write_ctree_super(NULL, root);
if (root->node)
btrfs_block_release(root, root->node);
if (root->fs_info->extent_root->node)
btrfs_block_release(root->fs_info->extent_root,
root->fs_info->extent_root->node);
if (root->fs_info->inode_root->node)
btrfs_block_release(root->fs_info->inode_root,
root->fs_info->inode_root->node);
if (root->fs_info->tree_root->node)
btrfs_block_release(root->fs_info->tree_root,
root->fs_info->tree_root->node);
btrfs_block_release(root, root->commit_root);
btrfs_block_release(root, root->fs_info->sb_buffer);
kfree(root->fs_info->extent_root);
kfree(root->fs_info->inode_root);
kfree(root->fs_info->tree_root);
kfree(root->fs_info);
kfree(root);
return 0;
}
void btrfs_block_release(struct btrfs_root *root, struct buffer_head *buf)
{
brelse(buf);
}
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