diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 6d6e1ac0a9a0aa55c0ee5816dad736a7beca0e8d..10cece11dbd832eef404621bdc8200f62f2e34e3 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -2250,13 +2250,10 @@ static int noinline create_subvol(struct btrfs_root *root, char *name, static int create_snapshot(struct btrfs_root *root, char *name, int namelen) { + struct btrfs_pending_snapshot *pending_snapshot; struct btrfs_trans_handle *trans; - struct btrfs_key key; - struct btrfs_root_item new_root_item; - struct extent_buffer *tmp; int ret; int err; - u64 objectid; unsigned long nr = 0; if (!root->ref_cows) @@ -2267,72 +2264,26 @@ static int create_snapshot(struct btrfs_root *root, char *name, int namelen) if (ret) goto fail_unlock; + pending_snapshot = kmalloc(sizeof(*pending_snapshot), GFP_NOFS); + if (!pending_snapshot) { + ret = -ENOMEM; + goto fail_unlock; + } + pending_snapshot->name = kstrndup(name, namelen, GFP_NOFS); + if (!pending_snapshot->name) { + ret = -ENOMEM; + kfree(pending_snapshot); + goto fail_unlock; + } trans = btrfs_start_transaction(root, 1); BUG_ON(!trans); - err = btrfs_commit_transaction(trans, root); - - trans = btrfs_start_transaction(root, 1); + pending_snapshot->root = root; + list_add(&pending_snapshot->list, + &trans->transaction->pending_snapshots); ret = btrfs_update_inode(trans, root, root->inode); - if (ret) - goto fail; - - ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root, - 0, &objectid); - if (ret) - goto fail; memcpy(&new_root_item, &root->root_item, - sizeof(new_root_item)); - - key.objectid = objectid; - key.offset = 1; - btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); - - extent_buffer_get(root->node); - btrfs_cow_block(trans, root, root->node, NULL, 0, &tmp); - free_extent_buffer(tmp); - - /* write the ordered inodes to force all delayed allocations to - * be filled. Once this is done, we can copy the root - */ - mutex_lock(&root->fs_info->trans_mutex); - btrfs_write_ordered_inodes(trans, root); - mutex_unlock(&root->fs_info->trans_mutex); - - btrfs_copy_root(trans, root, root->node, &tmp, objectid); - - btrfs_set_root_bytenr(&new_root_item, tmp->start); - btrfs_set_root_level(&new_root_item, btrfs_header_level(tmp)); - ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, - &new_root_item); -printk("new root %Lu node %Lu\n", objectid, tmp->start); - free_extent_buffer(tmp); - if (ret) - goto fail; - - /* - * insert the directory item - */ - key.offset = (u64)-1; - ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root, - name, namelen, - root->fs_info->sb->s_root->d_inode->i_ino, - &key, BTRFS_FT_DIR); - - if (ret) - goto fail; - - ret = btrfs_insert_inode_ref(trans, root->fs_info->tree_root, - name, namelen, objectid, - root->fs_info->sb->s_root->d_inode->i_ino); - - if (ret) - goto fail; -fail: - nr = trans->blocks_used; err = btrfs_commit_transaction(trans, root); - if (err && !ret) - ret = err; fail_unlock: mutex_unlock(&root->fs_info->fs_mutex); btrfs_btree_balance_dirty(root, nr); diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 3ed5868e7c0f680edecb2c6bad30232722f68402..dc9865323e38ea73253afdd331ba19929fa43175 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -66,6 +66,7 @@ static int join_transaction(struct btrfs_root *root) cur_trans->use_count = 1; cur_trans->commit_done = 0; cur_trans->start_time = get_seconds(); + INIT_LIST_HEAD(&cur_trans->pending_snapshots); list_add_tail(&cur_trans->list, &root->fs_info->trans_list); btrfs_ordered_inode_tree_init(&cur_trans->ordered_inode_tree); extent_map_tree_init(&cur_trans->dirty_pages, @@ -481,10 +482,8 @@ int btrfs_write_ordered_inodes(struct btrfs_trans_handle *trans, struct inode *inode; u64 root_objectid = 0; u64 objectid = 0; - u64 transid = trans->transid; int ret; -printk("write ordered trans %Lu\n", transid); while(1) { ret = btrfs_find_first_ordered_inode( &cur_trans->ordered_inode_tree, @@ -524,7 +523,80 @@ printk("write ordered trans %Lu\n", transid); mutex_lock(&root->fs_info->fs_mutex); mutex_lock(&root->fs_info->trans_mutex); } -printk("done write ordered trans %Lu\n", transid); + return 0; +} + +static int create_pending_snapshot(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_pending_snapshot *pending) +{ + struct btrfs_key key; + struct btrfs_root_item new_root_item; + struct btrfs_root *tree_root = fs_info->tree_root; + struct btrfs_root *root = pending->root; + struct extent_buffer *tmp; + int ret; + u64 objectid; + + ret = btrfs_find_free_objectid(trans, tree_root, 0, &objectid); + if (ret) + goto fail; + + memcpy(&new_root_item, &root->root_item, sizeof(new_root_item)); + + key.objectid = objectid; + key.offset = 1; + btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); + + extent_buffer_get(root->node); + btrfs_cow_block(trans, root, root->node, NULL, 0, &tmp); + free_extent_buffer(tmp); + + btrfs_copy_root(trans, root, root->node, &tmp, objectid); + + btrfs_set_root_bytenr(&new_root_item, tmp->start); + btrfs_set_root_level(&new_root_item, btrfs_header_level(tmp)); + ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, + &new_root_item); + free_extent_buffer(tmp); + if (ret) + goto fail; + + /* + * insert the directory item + */ + key.offset = (u64)-1; + ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root, + pending->name, strlen(pending->name), + root->fs_info->sb->s_root->d_inode->i_ino, + &key, BTRFS_FT_DIR); + + if (ret) + goto fail; + + ret = btrfs_insert_inode_ref(trans, root->fs_info->tree_root, + pending->name, strlen(pending->name), objectid, + root->fs_info->sb->s_root->d_inode->i_ino); +fail: + return ret; +} + +static int create_pending_snapshots(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info) +{ + struct btrfs_pending_snapshot *pending; + struct list_head *head = &trans->transaction->pending_snapshots; + int ret; + + while(!list_empty(head)) { + pending = list_entry(head->next, + struct btrfs_pending_snapshot, list); + ret = create_pending_snapshot(trans, fs_info, pending); + BUG_ON(ret); + list_del(&pending->list); + kfree(pending->name); + kfree(pending); + } return 0; } @@ -610,6 +682,9 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, } while (cur_trans->num_writers > 1 || (cur_trans->num_joined != joined)); + ret = create_pending_snapshots(trans, root->fs_info); + BUG_ON(ret); + WARN_ON(cur_trans != trans->transaction); ret = add_dirty_roots(trans, &root->fs_info->fs_roots_radix, diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h index c157ddbe9d1e72eb19d0b9fe169b76f6ee74c217..fd52e9b23922c0e53cb45b49ddb78048b6472d8d 100644 --- a/fs/btrfs/transaction.h +++ b/fs/btrfs/transaction.h @@ -34,6 +34,7 @@ struct btrfs_transaction { struct btrfs_ordered_inode_tree ordered_inode_tree; wait_queue_head_t writer_wait; wait_queue_head_t commit_wait; + struct list_head pending_snapshots; }; struct btrfs_trans_handle { @@ -46,6 +47,12 @@ struct btrfs_trans_handle { u64 alloc_exclude_nr; }; +struct btrfs_pending_snapshot { + struct btrfs_root *root; + char *name; + struct list_head list; +}; + static inline void btrfs_set_trans_block_group(struct btrfs_trans_handle *trans, struct inode *inode)