static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops,
			      void *tmplt_priv, u32 chain_index,
			      struct net *net, struct sk_buff *skb,
			      struct tcf_block *block,
			      u32 portid, u32 seq, u16 flags, int event)
{
	unsigned char *b = skb_tail_pointer(skb);
	const struct tcf_proto_ops *ops;
	struct nlmsghdr *nlh;
	struct tcmsg *tcm;
	void *priv;

	ops = tmplt_ops;
	priv = tmplt_priv;

	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
	if (!nlh)
		goto out_nlmsg_trim;
	tcm = nlmsg_data(nlh);
	tcm->tcm_family = AF_UNSPEC;
	tcm->tcm__pad1 = 0;
	tcm->tcm__pad2 = 0;
	tcm->tcm_handle = 0;
	if (block->q) {
		tcm->tcm_ifindex = qdisc_dev(block->q)->ifindex;
		tcm->tcm_parent = block->q->handle;
	} else {
		tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
		tcm->tcm_block_index = block->index;
	}

	if (nla_put_u32(skb, TCA_CHAIN, chain_index))
		goto nla_put_failure;

	if (ops) {
		if (nla_put_string(skb, TCA_KIND, ops->kind))
			goto nla_put_failure;
		if (ops->tmplt_dump(skb, net, priv) < 0)
			goto nla_put_failure;
	}

	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
	return skb->len;

out_nlmsg_trim:
nla_put_failure:
	nlmsg_trim(skb, b);
	return -EMSGSIZE;
}