#include "transaction.h"
 #include "btrfs_inode.h"
 
+void btrfs_fsinfo_release(struct kobject *obj)
+{
+       struct btrfs_fs_info *fsinfo = container_of(obj,
+                                           struct btrfs_fs_info, kobj);
+       kfree(fsinfo);
+}
+
+struct kobj_type btrfs_fsinfo_ktype = {
+       .release = btrfs_fsinfo_release,
+};
+
+decl_subsys(btrfs, &btrfs_fsinfo_ktype, NULL);
+
 #define BTRFS_SUPER_MAGIC 0x9123682E
 
 static struct inode_operations btrfs_dir_inode_operations;
+static struct inode_operations btrfs_dir_ro_inode_operations;
 static struct super_operations btrfs_super_ops;
 static struct file_operations btrfs_dir_file_operations;
 static struct inode_operations btrfs_file_inode_operations;
 {
        struct btrfs_path *path;
        struct btrfs_inode_item *inode_item;
-       struct btrfs_root *root = btrfs_sb(inode->i_sb);
+       struct btrfs_root *root = BTRFS_I(inode)->root;
+       struct btrfs_key location;
        int ret;
 
        path = btrfs_alloc_path();
        mutex_lock(&root->fs_info->fs_mutex);
 
        check_inode(inode);
-       ret = btrfs_lookup_inode(NULL, root, path, inode->i_ino, 0);
+
+       memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
+       ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
        if (ret) {
-               btrfs_release_path(root, path);
                btrfs_free_path(path);
-               mutex_unlock(&root->fs_info->fs_mutex);
-               make_bad_inode(inode);
-               return;
+               goto make_bad;
        }
        check_inode(inode);
        inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
        inode->i_blocks = btrfs_inode_nblocks(inode_item);
        inode->i_generation = btrfs_inode_generation(inode_item);
 
-       btrfs_release_path(root, path);
        btrfs_free_path(path);
        inode_item = NULL;
 
                inode->i_op = &btrfs_file_inode_operations;
                break;
        case S_IFDIR:
-               inode->i_op = &btrfs_dir_inode_operations;
                inode->i_fop = &btrfs_dir_file_operations;
+               if (root == root->fs_info->tree_root)
+                       inode->i_op = &btrfs_dir_ro_inode_operations;
+               else
+                       inode->i_op = &btrfs_dir_inode_operations;
                break;
        case S_IFLNK:
                // inode->i_op = &page_symlink_inode_operations;
        }
        check_inode(inode);
        return;
+
+make_bad:
+       btrfs_release_path(root, path);
+       btrfs_free_path(path);
+       mutex_unlock(&root->fs_info->fs_mutex);
+       make_bad_inode(inode);
 }
 
 static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
        }
        di = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
                            struct btrfs_dir_item);
-       objectid = btrfs_dir_objectid(di);
+       objectid = btrfs_disk_key_objectid(&di->location);
 
        ret = btrfs_del_item(trans, root, path);
        BUG_ON(ret);
        struct btrfs_trans_handle *trans;
        int ret;
 
-       root = btrfs_sb(dir->i_sb);
+       root = BTRFS_I(dir)->root;
        mutex_lock(&root->fs_info->fs_mutex);
        trans = btrfs_start_transaction(root, 1);
        ret = btrfs_unlink_trans(trans, root, dir, dentry);
        struct inode *inode = dentry->d_inode;
        int err;
        int ret;
-       struct btrfs_root *root = btrfs_sb(dir->i_sb);
+       struct btrfs_root *root = BTRFS_I(dir)->root;
        struct btrfs_path *path;
        struct btrfs_key key;
        struct btrfs_trans_handle *trans;
        BUG_ON(ret);
        btrfs_release_path(root, path);
 
-       ret = btrfs_lookup_inode(trans, root, path, objectid, -1);
+       ret = btrfs_lookup_inode(trans, root, path,
+                                &BTRFS_I(inode)->location, -1);
        BUG_ON(ret);
        ret = btrfs_del_item(trans, root, path);
        BUG_ON(ret);
 static void btrfs_delete_inode(struct inode *inode)
 {
        struct btrfs_trans_handle *trans;
-       struct btrfs_root *root = btrfs_sb(inode->i_sb);
+       struct btrfs_root *root = BTRFS_I(inode)->root;
        int ret;
 
        truncate_inode_pages(&inode->i_data, 0);
 }
 
 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
-                             ino_t *ino)
+                              struct btrfs_key *location)
 {
        const char *name = dentry->d_name.name;
        int namelen = dentry->d_name.len;
        struct btrfs_dir_item *di;
        struct btrfs_path *path;
-       struct btrfs_root *root = btrfs_sb(dir->i_sb);
+       struct btrfs_root *root = BTRFS_I(dir)->root;
        int ret;
 
        path = btrfs_alloc_path();
        ret = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
                                    namelen, 0);
        if (ret || !btrfs_match_dir_item_name(root, path, name, namelen)) {
-               *ino = 0;
+               location->objectid = 0;
                ret = 0;
                goto out;
        }
        di = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
                            struct btrfs_dir_item);
-       *ino = btrfs_dir_objectid(di);
+       btrfs_disk_key_to_cpu(location, &di->location);
 out:
        btrfs_release_path(root, path);
        btrfs_free_path(path);
        return ret;
 }
 
+int fixup_tree_root_location(struct btrfs_root *root,
+                            struct btrfs_key *location,
+                            struct btrfs_root **sub_root)
+{
+       struct btrfs_path *path;
+       struct btrfs_root_item *ri;
+       int ret;
+
+       if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
+               return 0;
+       if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
+               return 0;
+
+       path = btrfs_alloc_path();
+       BUG_ON(!path);
+       mutex_lock(&root->fs_info->fs_mutex);
+
+       ret = btrfs_lookup_inode(NULL, root, path, location, 0);
+       if (ret)
+               goto out;
+       ri = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
+                         path->slots[0],
+                         struct btrfs_root_item);
+       location->objectid = btrfs_root_dirid(ri);
+       location->flags = 0;
+       btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
+       location->offset = 0;
+       /* FIXME properly select the root */
+       *sub_root = root->fs_info->fs_root;
+out:
+       btrfs_free_path(path);
+       mutex_unlock(&root->fs_info->fs_mutex);
+       return ret;
+}
+
+
 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
                                   struct nameidata *nd)
 {
        struct inode * inode;
-       struct btrfs_root *root = btrfs_sb(dir->i_sb);
-       ino_t ino;
+       struct btrfs_inode *bi = BTRFS_I(dir);
+       struct btrfs_root *root = bi->root;
+       struct btrfs_root *sub_root = root;
+       struct btrfs_key location;
        int ret;
 
        if (dentry->d_name.len > BTRFS_NAME_LEN)
                return ERR_PTR(-ENAMETOOLONG);
        mutex_lock(&root->fs_info->fs_mutex);
-       ret = btrfs_inode_by_name(dir, dentry, &ino);
+       ret = btrfs_inode_by_name(dir, dentry, &location);
        mutex_unlock(&root->fs_info->fs_mutex);
        if (ret < 0)
                return ERR_PTR(ret);
        inode = NULL;
-       if (ino) {
-               inode = iget(dir->i_sb, ino);
+       if (location.objectid) {
+               ret = fixup_tree_root_location(root, &location, &sub_root);
+               if (ret < 0)
+                       return ERR_PTR(ret);
+               if (ret > 0)
+                       return ERR_PTR(-ENOENT);
+               inode = iget_locked(dir->i_sb, location.objectid);
                if (!inode)
                        return ERR_PTR(-EACCES);
+               if (inode->i_state & I_NEW) {
+                       BTRFS_I(inode)->root = sub_root;
+                       memcpy(&BTRFS_I(inode)->location, &location,
+                              sizeof(location));
+                       btrfs_read_locked_inode(inode);
+                       unlock_new_inode(inode);
+               }
                check_inode(inode);
        }
        check_inode(dir);
 static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 {
        struct inode *inode = filp->f_path.dentry->d_inode;
-       struct btrfs_root *root = btrfs_sb(inode->i_sb);
+       struct btrfs_root *root = BTRFS_I(inode)->root;
        struct btrfs_item *item;
        struct btrfs_dir_item *di;
        struct btrfs_key key;
        int advance;
        unsigned char d_type = DT_UNKNOWN;
        int over = 0;
+       int key_type = BTRFS_DIR_INDEX_KEY;
+
+       /* FIXME, use a real flag for deciding about the key type */
+       if (root->fs_info->tree_root == root)
+               key_type = BTRFS_DIR_ITEM_KEY;
 
        mutex_lock(&root->fs_info->fs_mutex);
        key.objectid = inode->i_ino;
        key.flags = 0;
-       btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
+       btrfs_set_key_type(&key, key_type);
        key.offset = filp->f_pos;
        path = btrfs_alloc_path();
        btrfs_init_path(path);
                item = leaf->items + slot;
                if (btrfs_disk_key_objectid(&item->key) != key.objectid)
                        break;
-               if (btrfs_disk_key_offset(&item->key) >
+               if (key_type == BTRFS_DIR_INDEX_KEY &&
+                   btrfs_disk_key_offset(&item->key) >
                    root->fs_info->highest_inode)
                        break;
-               if (btrfs_disk_key_type(&item->key) != BTRFS_DIR_INDEX_KEY)
+               if (btrfs_disk_key_type(&item->key) != key_type)
                        continue;
                if (btrfs_disk_key_offset(&item->key) < filp->f_pos)
                        continue;
                over = filldir(dirent, (const char *)(di + 1),
                               btrfs_dir_name_len(di),
                               btrfs_disk_key_offset(&item->key),
-                              btrfs_dir_objectid(di), d_type);
+                              btrfs_disk_key_objectid(&di->location), d_type);
                if (over)
                        goto nopos;
        }
        struct dentry * root_dentry;
        struct btrfs_super_block *disk_super;
        struct btrfs_root *root;
+       struct btrfs_inode *bi;
 
        sb->s_maxbytes = MAX_LFS_FILESIZE;
        sb->s_magic = BTRFS_SUPER_MAGIC;
               btrfs_super_root_dir(disk_super));
 
        inode = iget_locked(sb, btrfs_super_root_dir(disk_super));
+       bi = BTRFS_I(inode);
+       bi->location.objectid = inode->i_ino;
+       bi->location.offset = 0;
+       bi->location.flags = 0;
+       bi->root = root->fs_info->tree_root;
+       btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY);
+
        if (!inode)
                return -ENOMEM;
        if (inode->i_state & I_NEW) {
        BUG_ON(!path);
        btrfs_init_path(path);
 
-       ret = btrfs_lookup_inode(trans, root, path, inode->i_ino, 1);
+       ret = btrfs_lookup_inode(trans, root, path,
+                                &BTRFS_I(inode)->location, 1);
        if (ret) {
                if (ret > 0)
                        ret = -ENOENT;
 
 static int btrfs_write_inode(struct inode *inode, int wait)
 {
-       struct btrfs_root *root = btrfs_sb(inode->i_sb);
+       struct btrfs_root *root = BTRFS_I(inode)->root;
        struct btrfs_trans_handle *trans;
        int ret;
 
 {
        struct inode *inode;
        struct btrfs_inode_item inode_item;
-       struct btrfs_root *root = btrfs_sb(dir->i_sb);
-       struct btrfs_key key;
+       struct btrfs_root *root = BTRFS_I(dir)->root;
+       struct btrfs_key *key;
        int ret;
        u64 objectid;
 
        if (!inode)
                return ERR_PTR(-ENOMEM);
 
+       BTRFS_I(inode)->root = BTRFS_I(dir)->root;
+       key = &BTRFS_I(inode)->location;
        check_inode(inode);
        ret = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
        BUG_ON(ret);
        inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
        fill_inode_item(&inode_item, inode);
 
-       key.objectid = objectid;
-       key.flags = 0;
-       key.offset = 0;
-       btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
-       ret = btrfs_insert_inode_map(trans, root, objectid, &key);
+       key->objectid = objectid;
+       key->flags = 0;
+       key->offset = 0;
+       btrfs_set_key_type(key, BTRFS_INODE_ITEM_KEY);
+       ret = btrfs_insert_inode_map(trans, root, objectid, key);
        BUG_ON(ret);
 
        ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
                            struct dentry *dentry, struct inode *inode)
 {
        int ret;
-       ret = btrfs_insert_dir_item(trans, btrfs_sb(inode->i_sb),
+       struct btrfs_key key;
+       struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
+       key.objectid = inode->i_ino;
+       key.flags = 0;
+       btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
+       key.offset = 0;
+
+       ret = btrfs_insert_dir_item(trans, root,
                                    dentry->d_name.name, dentry->d_name.len,
                                    dentry->d_parent->d_inode->i_ino,
-                                   inode->i_ino, 0);
+                                   &key, 0);
        if (ret == 0) {
                dentry->d_parent->d_inode->i_size += dentry->d_name.len * 2;
-               ret = btrfs_update_inode(trans, btrfs_sb(inode->i_sb),
+               ret = btrfs_update_inode(trans, root,
                                         dentry->d_parent->d_inode);
        }
        check_inode(inode);
                        int mode, struct nameidata *nd)
 {
        struct btrfs_trans_handle *trans;
-       struct btrfs_root *root = btrfs_sb(dir->i_sb);
+       struct btrfs_root *root = BTRFS_I(dir)->root;
        struct inode *inode;
        int err;
        int drop_inode = 0;
 static int btrfs_make_empty_dir(struct btrfs_trans_handle *trans,
                                struct inode *inode, struct inode *dir)
 {
-       struct btrfs_root *root = btrfs_sb(inode->i_sb);
+       struct btrfs_root *root = BTRFS_I(dir)->root;
        int ret;
        char buf[2];
+       struct btrfs_key key;
+
        buf[0] = '.';
        buf[1] = '.';
 
+       key.objectid = inode->i_ino;
+       key.offset = 0;
+       key.flags = 0;
+       btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
+
        ret = btrfs_insert_dir_item(trans, root, buf, 1, inode->i_ino,
-                                   inode->i_ino, 1);
+                                   &key, 1);
        if (ret)
                goto error;
+       key.objectid = dir->i_ino;
        ret = btrfs_insert_dir_item(trans, root, buf, 2, inode->i_ino,
-                                   dir->i_ino, 1);
+                                   &key, 1);
        if (ret)
                goto error;
        inode->i_size = 6;
 {
        struct inode *inode;
        struct btrfs_trans_handle *trans;
-       struct btrfs_root *root = btrfs_sb(dir->i_sb);
+       struct btrfs_root *root = BTRFS_I(dir)->root;
        int err = 0;
        int drop_on_err = 0;
 
        u64 extent_end = 0;
        u64 objectid = inode->i_ino;
        struct btrfs_path *path;
-       struct btrfs_root *root = btrfs_sb(inode->i_sb);
+       struct btrfs_root *root = BTRFS_I(inode)->root;
        struct btrfs_trans_handle *trans = NULL;
        struct btrfs_file_extent_item *item;
        struct btrfs_leaf *leaf;
                           struct buffer_head *result, int create)
 {
        int err;
-       struct btrfs_root *root = btrfs_sb(inode->i_sb);
+       struct btrfs_root *root = BTRFS_I(inode)->root;
        mutex_lock(&root->fs_info->fs_mutex);
        err = btrfs_get_block_lock(inode, iblock, result, create);
        // err = btrfs_get_block_inline(inode, iblock, result, create);
 
 static void btrfs_truncate(struct inode *inode)
 {
-       struct btrfs_root *root = btrfs_sb(inode->i_sb);
+       struct btrfs_root *root = BTRFS_I(inode)->root;
        int ret;
        struct btrfs_trans_handle *trans;
 
        int err = 0;
        int ret = 0;
        struct inode *inode = file->f_path.dentry->d_inode;
-       struct btrfs_root *root = btrfs_sb(inode->i_sb);
+       struct btrfs_root *root = BTRFS_I(inode)->root;
        struct page *pages[1];
 
        if (file->f_flags & O_DIRECT)
        int err = 0;
        int ret = 0;
        struct inode *inode = file->f_path.dentry->d_inode;
-       struct btrfs_root *root = btrfs_sb(inode->i_sb);
+       struct btrfs_root *root = BTRFS_I(inode)->root;
        unsigned long page_index;
 
        if (file->f_flags & O_DIRECT)
 {
        char *kaddr;
        unsigned long left, count = desc->count;
+       struct inode *inode = page->mapping->host;
 
        if (size > count)
                size = count;
 
        if (!PageChecked(page)) {
                /* FIXME, do it per block */
-               struct btrfs_root *root = btrfs_sb(page->mapping->host->i_sb);
+               struct btrfs_root *root = BTRFS_I(inode)->root;
                int ret = btrfs_csum_verify_file_block(root,
                                          page->mapping->host->i_ino,
                                          page->index << PAGE_CACHE_SHIFT,
        .rmdir          = btrfs_rmdir,
 };
 
+static struct inode_operations btrfs_dir_ro_inode_operations = {
+       .lookup         = btrfs_lookup,
+};
+
 static struct file_operations btrfs_dir_file_operations = {
        .llseek         = generic_file_llseek,
        .read           = generic_read_dir,
        err = init_inodecache();
        if (err)
                return err;
+       kset_set_kset_s(&btrfs_subsys, fs_subsys);
+       err = subsystem_register(&btrfs_subsys);
+       if (err)
+               goto out;
        return register_filesystem(&btrfs_fs_type);
+out:
+       destroy_inodecache();
+       return err;
 }
 
 static void __exit exit_btrfs_fs(void)
 {
        destroy_inodecache();
        unregister_filesystem(&btrfs_fs_type);
+       subsystem_unregister(&btrfs_subsys);
        printk("btrfs unloaded\n");
 }