Function tap_flow_implicit_create

dpdk/drivers/net/tap/tap_flow.c:1680–1775

* Add an implicit flow rule on the remote device to make sure traffic gets to * the tap netdevice from there. * * @param pmd * Pointer to private structure. * @param[in] idx * The idx in the implicit_rte_flows array specifying which rule to apply. * * @return -1 if the rule couldn't be applied, 0 otherwise. */

 * @return -1 if the rule couldn't be applied, 0 otherwise.
 */
int tap_flow_implicit_create(struct pmd_internals *pmd,
			     enum implicit_rule_index idx)
{
	uint16_t flags = NLM_F_REQUEST | NLM_F_ACK | NLM_F_EXCL | NLM_F_CREATE;
	struct rte_flow_action *actions = implicit_rte_flows[idx].actions;
	struct rte_flow_action isolate_actions[2] = {
		[1] = {
			.type = RTE_FLOW_ACTION_TYPE_END,
		},
	};
	struct rte_flow_item *items = implicit_rte_flows[idx].items;
	struct rte_flow_attr *attr = &implicit_rte_flows[idx].attr;
	struct rte_flow_item_eth eth_local = { .hdr.ether_type = 0 };
	unsigned int if_index = pmd->remote_if_index;
	struct rte_flow *remote_flow = NULL;
	struct nlmsg *msg = NULL;
	int err = 0;
	struct rte_flow_item items_local[2] = {
		[0] = {
			.type = items[0].type,
			.spec = &eth_local,
			.mask = items[0].mask,
		},
		[1] = {
			.type = items[1].type,
		}
	};

	remote_flow = rte_zmalloc(__func__, sizeof(struct rte_flow), 0);
	if (!remote_flow) {
		TAP_LOG(ERR, "Cannot allocate memory for rte_flow");
		goto fail;
	}
	msg = &remote_flow->msg;
	if (idx == TAP_REMOTE_TX) {
		if_index = pmd->if_index;
	} else if (idx == TAP_ISOLATE) {
		if_index = pmd->if_index;
		/* Don't be exclusive for this rule, it can be changed later. */
		flags = NLM_F_REQUEST | NLM_F_ACK | NLM_F_CREATE;
		isolate_actions[0].type = pmd->flow_isolate ?
			RTE_FLOW_ACTION_TYPE_DROP :
			RTE_FLOW_ACTION_TYPE_PASSTHRU;
		actions = isolate_actions;
	} else if (idx == TAP_REMOTE_LOCAL_MAC) {
		/*
		 * eth addr couldn't be set in implicit_rte_flows[] as it is not
		 * known at compile time.
		 */
		memcpy(&eth_local.hdr.dst_addr, &pmd->eth_addr, sizeof(pmd->eth_addr));
		items = items_local;
	}
	tc_init_msg(msg, if_index, RTM_NEWTFILTER, flags);
	msg->t.tcm_info = TC_H_MAKE(0, htons(ETH_P_ALL));
	/*
	 * The ISOLATE rule is always present and must have a static handle, as
	 * the action is changed whether the feature is enabled (DROP) or
	 * disabled (PASSTHRU).