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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;
}
int write_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct buffer_head *buf)
{
mark_buffer_dirty(buf);
return 0;
}
static int __commit_transaction(struct btrfs_trans_handle *trans, struct
btrfs_root *root)
{
filemap_write_and_wait(root->fs_info->sb->s_bdev->bd_inode->i_mapping);
return 0;
}
static int commit_tree_roots(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info)
{
int ret;
u64 old_extent_block;
struct btrfs_root *tree_root = fs_info->tree_root;
struct btrfs_root *extent_root = fs_info->extent_root;
struct btrfs_root *inode_root = fs_info->inode_root;
btrfs_set_root_blocknr(&inode_root->root_item,
inode_root->node->b_blocknr);
ret = btrfs_update_root(trans, tree_root,
&inode_root->root_key,
&inode_root->root_item);
BUG_ON(ret);
while(1) {
old_extent_block = btrfs_root_blocknr(&extent_root->root_item);
if (old_extent_block == extent_root->node->b_blocknr)
break;
btrfs_set_root_blocknr(&extent_root->root_item,
extent_root->node->b_blocknr);
ret = btrfs_update_root(trans, tree_root,
&extent_root->root_key,
&extent_root->root_item);
BUG_ON(ret);
}
return 0;
}
int btrfs_commit_transaction(struct btrfs_trans_handle *trans, struct
btrfs_root *root, struct btrfs_super_block *s)
{
int ret = 0;
struct buffer_head *snap = root->commit_root;
struct btrfs_key snap_key;
if (root->commit_root == root->node)
return 0;
memcpy(&snap_key, &root->root_key, sizeof(snap_key));
root->root_key.offset++;
btrfs_set_root_blocknr(&root->root_item, root->node->b_blocknr);
ret = btrfs_insert_root(trans, root->fs_info->tree_root,
&root->root_key, &root->root_item);
BUG_ON(ret);
ret = commit_tree_roots(trans, root->fs_info);
BUG_ON(ret);
ret = __commit_transaction(trans, root);
BUG_ON(ret);
write_ctree_super(trans, root, s);
btrfs_finish_extent_commit(trans, root->fs_info->extent_root);
btrfs_finish_extent_commit(trans, root->fs_info->tree_root);
root->commit_root = root->node;
get_bh(root->node);
ret = btrfs_drop_snapshot(trans, root, snap);
BUG_ON(ret);
ret = btrfs_del_root(trans, root->fs_info->tree_root, &snap_key);
BUG_ON(ret);
root->fs_info->generation = root->root_key.offset + 1;
return ret;
}
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;
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 btrfs_super_block *s)
{
return 0;
#if 0
int ret;
btrfs_set_super_root(s, root->fs_info->tree_root->node->b_blocknr);
ret = pwrite(root->fs_info->fp, s, sizeof(*s),
BTRFS_SUPER_INFO_OFFSET);
if (ret != sizeof(*s)) {
fprintf(stderr, "failed to write new super block err %d\n", ret);
return ret;
}
return 0;
#endif
}
static int drop_cache(struct btrfs_root *root)
{
return 0;
#if 0
while(!list_empty(&root->fs_info->cache)) {
struct buffer_head *b = list_entry(root->fs_info->cache.next,
struct buffer_head,
cache);
list_del_init(&b->cache);
btrfs_block_release(root, b);
}
return 0;
#endif
}
int close_ctree(struct btrfs_root *root)
{
int ret;
struct btrfs_trans_handle *trans;
trans = root->fs_info->running_transaction;
btrfs_commit_transaction(trans, root, root->fs_info->disk_super);
ret = commit_tree_roots(trans, root->fs_info);
BUG_ON(ret);
ret = __commit_transaction(trans, root);
BUG_ON(ret);
write_ctree_super(trans, root, root->fs_info->disk_super);
drop_cache(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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