[dpdk-dev] [RFC] ethdev: add new fields for max LRO session size

[Matan Azrad]

It may be needed by the user to limit the LRO session packet size.
In order to allow the above limitation, add new Rx configuration for
the maximum LRO session size.

In addition, Add a new capability to expose the maximum LRO session
size supported by the port.

Signed-off-by: Matan Azrad <matan at mellanox.com>
---
 doc/guides/nics/features.rst   | 2 ++
 lib/librte_ethdev/rte_ethdev.h | 3 +++
 2 files changed, 5 insertions(+)

diff --git a/doc/guides/nics/features.rst b/doc/guides/nics/features.rst
index c4e128d..6d1c8a5 100644
--- a/doc/guides/nics/features.rst
+++ b/doc/guides/nics/features.rst
@@ -193,10 +193,12 @@ LRO
 Supports Large Receive Offload.
 
 * **[uses]       rte_eth_rxconf,rte_eth_rxmode**: ``offloads:DEV_RX_OFFLOAD_TCP_LRO``.
+  ``dev_conf.rxmode.max_lro_session_len``.
 * **[implements] datapath**: ``LRO functionality``.
 * **[implements] rte_eth_dev_data**: ``lro``.
 * **[provides]   mbuf**: ``mbuf.ol_flags:PKT_RX_LRO``, ``mbuf.tso_segsz``.
 * **[provides]   rte_eth_dev_info**: ``rx_offload_capa,rx_queue_offload_capa:DEV_RX_OFFLOAD_TCP_LRO``.
+* **[provides]   rte_eth_dev_info**: ``max_lro_session_len``.
 
 
 .. _nic_features_tso:
diff --git a/lib/librte_ethdev/rte_ethdev.h b/lib/librte_ethdev/rte_ethdev.h
index dc6596b..6dbb9d9 100644
--- a/lib/librte_ethdev/rte_ethdev.h
+++ b/lib/librte_ethdev/rte_ethdev.h
@@ -395,6 +395,7 @@ struct rte_eth_rxmode {
 	/** The multi-queue packet distribution mode to be used, e.g. RSS. */
 	enum rte_eth_rx_mq_mode mq_mode;
 	uint32_t max_rx_pkt_len;  /**< Only used if JUMBO_FRAME enabled. */
+	uint32_t max_lro_session_len;  /**< The maximum LRO session size. */
 	uint16_t split_hdr_size;  /**< hdr buf size (header_split enabled).*/
 	/**
 	 * Per-port Rx offloads to be set using DEV_RX_OFFLOAD_* flags.
@@ -1148,6 +1149,8 @@ struct rte_eth_dev_info {
 	const uint32_t *dev_flags; /**< Device flags */
 	uint32_t min_rx_bufsize; /**< Minimum size of RX buffer. */
 	uint32_t max_rx_pktlen; /**< Maximum configurable length of RX pkt. */
+	uint32_t max_lro_session_len;
+	/**< Maximum configurable length of LRO session. */
 	uint16_t max_rx_queues; /**< Maximum number of RX queues. */
 	uint16_t max_tx_queues; /**< Maximum number of TX queues. */
 	uint32_t max_mac_addrs; /**< Maximum number of MAC addresses. */
-- 
1.8.3.1