API: IP Fragment Handling

It is possible to identify all fragments and forward to a specific queue as shown in the following example.

/* Create group 0 flow to forward IPv4 fragments to queue 1. */
struct rte_flow_attr attr = { .group = 0, .ingress = 1 };

struct rte_flow_item_ipv4 ipv4 = { .hdr = {
  .fragment_offset = RTE_BE16(0xffff) }};
struct rte_flow_item pattern[] = {
  [0] = { .type = RTE_FLOW_ITEM_TYPE_IPV4, .spec = &ipv4, .mask = &ipv4 },
  [1] = { .type = RTE_FLOW_ITEM_TYPE_END }};

struct rte_flow_action_queue queue = { .index = 1 };
struct rte_flow_action action[] = {
  [0] = { .type = RTE_FLOW_ACTION_TYPE_QUEUE, .conf = &queue },
  [1] = { .type = RTE_FLOW_ACTION_TYPE_END }};

struct rte_flow_error error;
struct rte_flow *flow = rte_flow_create(PORT_ID, &attr, pattern, action, &error);
if (!flow) {
  /* Error handling */
}

This example creates a flow rule with a group ID of 1 for frames received on port 1. The pattern array includes an IPv4 item with a specific mask matching the fragment offset field for all fragments. The action is defined to forward the traffic to queue 1.