diff options
Diffstat (limited to 'fs/btrfs/transaction.c')
-rw-r--r-- | fs/btrfs/transaction.c | 131 |
1 files changed, 90 insertions, 41 deletions
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 21ad37c0519..2616491a5c5 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -165,53 +165,89 @@ enum btrfs_trans_type { TRANS_USERSPACE, }; +static int may_wait_transaction(struct btrfs_root *root, int type) +{ + if (!root->fs_info->log_root_recovering && + ((type == TRANS_START && !root->fs_info->open_ioctl_trans) || + type == TRANS_USERSPACE)) + return 1; + return 0; +} + static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root, - int num_blocks, int type) + u64 num_items, int type) { - struct btrfs_trans_handle *h = - kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS); + struct btrfs_trans_handle *h; + struct btrfs_transaction *cur_trans; + int retries = 0; int ret; +again: + h = kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS); + if (!h) + return ERR_PTR(-ENOMEM); mutex_lock(&root->fs_info->trans_mutex); - if (!root->fs_info->log_root_recovering && - ((type == TRANS_START && !root->fs_info->open_ioctl_trans) || - type == TRANS_USERSPACE)) + if (may_wait_transaction(root, type)) wait_current_trans(root); + ret = join_transaction(root); BUG_ON(ret); - h->transid = root->fs_info->running_transaction->transid; - h->transaction = root->fs_info->running_transaction; - h->blocks_reserved = num_blocks; + cur_trans = root->fs_info->running_transaction; + cur_trans->use_count++; + mutex_unlock(&root->fs_info->trans_mutex); + + h->transid = cur_trans->transid; + h->transaction = cur_trans; h->blocks_used = 0; h->block_group = 0; + h->bytes_reserved = 0; h->delayed_ref_updates = 0; h->block_rsv = NULL; - if (!current->journal_info && type != TRANS_USERSPACE) - current->journal_info = h; + smp_mb(); + if (cur_trans->blocked && may_wait_transaction(root, type)) { + btrfs_commit_transaction(h, root); + goto again; + } + + if (num_items > 0) { + ret = btrfs_trans_reserve_metadata(h, root, num_items, + &retries); + if (ret == -EAGAIN) { + btrfs_commit_transaction(h, root); + goto again; + } + if (ret < 0) { + btrfs_end_transaction(h, root); + return ERR_PTR(ret); + } + } - root->fs_info->running_transaction->use_count++; + mutex_lock(&root->fs_info->trans_mutex); record_root_in_trans(h, root); mutex_unlock(&root->fs_info->trans_mutex); + + if (!current->journal_info && type != TRANS_USERSPACE) + current->journal_info = h; return h; } struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, - int num_blocks) + int num_items) { - return start_transaction(root, num_blocks, TRANS_START); + return start_transaction(root, num_items, TRANS_START); } struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root, int num_blocks) { - return start_transaction(root, num_blocks, TRANS_JOIN); + return start_transaction(root, 0, TRANS_JOIN); } struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *r, int num_blocks) { - return start_transaction(r, num_blocks, TRANS_USERSPACE); + return start_transaction(r, 0, TRANS_USERSPACE); } /* wait for a transaction commit to be fully complete */ @@ -312,6 +348,8 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, count++; } + btrfs_trans_release_metadata(trans, root); + mutex_lock(&info->trans_mutex); cur_trans = info->running_transaction; WARN_ON(cur_trans != trans->transaction); @@ -757,47 +795,49 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root *root = pending->root; struct btrfs_root *parent_root; struct inode *parent_inode; + struct dentry *dentry; struct extent_buffer *tmp; struct extent_buffer *old; int ret; - u64 objectid; - int namelen; u64 index = 0; - - parent_inode = pending->dentry->d_parent->d_inode; - parent_root = BTRFS_I(parent_inode)->root; + u64 objectid; new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS); if (!new_root_item) { - ret = -ENOMEM; + pending->error = -ENOMEM; goto fail; } + ret = btrfs_find_free_objectid(trans, tree_root, 0, &objectid); - if (ret) + if (ret) { + pending->error = ret; goto fail; + } key.objectid = objectid; - /* record when the snapshot was created in key.offset */ - key.offset = trans->transid; - btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); + key.offset = (u64)-1; + key.type = BTRFS_ROOT_ITEM_KEY; - memcpy(&pending->root_key, &key, sizeof(key)); - pending->root_key.offset = (u64)-1; + trans->block_rsv = &pending->block_rsv; + dentry = pending->dentry; + parent_inode = dentry->d_parent->d_inode; + parent_root = BTRFS_I(parent_inode)->root; record_root_in_trans(trans, parent_root); + /* * insert the directory item */ - namelen = strlen(pending->name); ret = btrfs_set_inode_index(parent_inode, &index); BUG_ON(ret); ret = btrfs_insert_dir_item(trans, parent_root, - pending->name, namelen, - parent_inode->i_ino, - &pending->root_key, BTRFS_FT_DIR, index); + dentry->d_name.name, dentry->d_name.len, + parent_inode->i_ino, &key, + BTRFS_FT_DIR, index); BUG_ON(ret); - btrfs_i_size_write(parent_inode, parent_inode->i_size + namelen * 2); + btrfs_i_size_write(parent_inode, parent_inode->i_size + + dentry->d_name.len * 2); ret = btrfs_update_inode(trans, parent_root, parent_inode); BUG_ON(ret); @@ -814,22 +854,29 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, free_extent_buffer(old); btrfs_set_root_node(new_root_item, tmp); - ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, - new_root_item); - BUG_ON(ret); + /* record when the snapshot was created in key.offset */ + key.offset = trans->transid; + ret = btrfs_insert_root(trans, tree_root, &key, new_root_item); btrfs_tree_unlock(tmp); free_extent_buffer(tmp); + BUG_ON(ret); - ret = btrfs_add_root_ref(trans, parent_root->fs_info->tree_root, - pending->root_key.objectid, + /* + * insert root back/forward references + */ + ret = btrfs_add_root_ref(trans, tree_root, objectid, parent_root->root_key.objectid, - parent_inode->i_ino, index, pending->name, - namelen); + parent_inode->i_ino, index, + dentry->d_name.name, dentry->d_name.len); BUG_ON(ret); + key.offset = (u64)-1; + pending->snap = btrfs_read_fs_root_no_name(root->fs_info, &key); + BUG_ON(IS_ERR(pending->snap)); fail: kfree(new_root_item); - return ret; + btrfs_block_rsv_release(root, &pending->block_rsv, (u64)-1); + return 0; } /* @@ -898,6 +945,8 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, ret = btrfs_run_delayed_refs(trans, root, 0); BUG_ON(ret); + btrfs_trans_release_metadata(trans, root); + cur_trans = trans->transaction; /* * set the flushing flag so procs in this transaction have to |