[PATCH v9 1/4] ethdev: introduce protocol header API

[Yuan Wang <yuanx.wang@intel.com>]

Add a new ethdev API to retrieve supported protocol headers
of a PMD, which helps to configure protocol header based buffer split.

Signed-off-by: Yuan Wang <yuanx.wang@intel.com>
Signed-off-by: Xuan Ding <xuan.ding@intel.com>
Signed-off-by: Wenxuan Wu <wenxuanx.wu@intel.com>
Reviewed-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
---
 doc/guides/nics/features.rst           |  2 +-
 doc/guides/rel_notes/release_22_11.rst |  5 ++++
 lib/ethdev/ethdev_driver.h             | 15 ++++++++++++
 lib/ethdev/rte_ethdev.c                | 33 ++++++++++++++++++++++++++
 lib/ethdev/rte_ethdev.h                | 30 +++++++++++++++++++++++
 lib/ethdev/version.map                 |  1 +
 6 files changed, 85 insertions(+), 1 deletion(-)

diff --git a/doc/guides/nics/features.rst b/doc/guides/nics/features.rst
index 6aa1085c5b..fea604e77f 100644
--- a/doc/guides/nics/features.rst
+++ b/doc/guides/nics/features.rst
@@ -183,7 +183,7 @@ Scatters the packets being received on specified boundaries to segmented mbufs.
 * **[uses]       rte_eth_rxconf**: ``rx_conf.rx_seg, rx_conf.rx_nseg``.
 * **[implements] datapath**: ``Buffer Split functionality``.
 * **[provides]   rte_eth_dev_info**: ``rx_offload_capa:RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT``.
-* **[related] API**: ``rte_eth_rx_queue_setup()``.
+* **[related] API**: ``rte_eth_rx_queue_setup()``, ``rte_eth_buffer_split_get_supported_hdr_ptypes()``.
 
 
 .. _nic_features_lro:
diff --git a/doc/guides/rel_notes/release_22_11.rst b/doc/guides/rel_notes/release_22_11.rst
index c560dbdab7..16aca14bab 100644
--- a/doc/guides/rel_notes/release_22_11.rst
+++ b/doc/guides/rel_notes/release_22_11.rst
@@ -189,6 +189,11 @@ New Features
   into single event containing ``rte_event_vector``
   whose event type is ``RTE_EVENT_TYPE_CRYPTODEV_VECTOR``.
 
+* **Added protocol header based buffer split.**
+
+  * Added ``rte_eth_buffer_split_get_supported_hdr_ptypes()``, to get supported
+    header protocols of a PMD to split.
+
 
 Removed Items
 -------------
diff --git a/lib/ethdev/ethdev_driver.h b/lib/ethdev/ethdev_driver.h
index e2bd4642b9..1300acc95d 100644
--- a/lib/ethdev/ethdev_driver.h
+++ b/lib/ethdev/ethdev_driver.h
@@ -1055,6 +1055,18 @@ typedef int (*eth_ip_reassembly_conf_get_t)(struct rte_eth_dev *dev,
 typedef int (*eth_ip_reassembly_conf_set_t)(struct rte_eth_dev *dev,
 		const struct rte_eth_ip_reassembly_params *conf);
 
+/**
+ * @internal
+ * Get supported header protocols of a PMD to split.
+ *
+ * @param dev
+ *   Ethdev handle of port.
+ *
+ * @return
+ *   An array pointer to store supported protocol headers.
+ */
+typedef const uint32_t *(*eth_buffer_split_supported_hdr_ptypes_get_t)(struct rte_eth_dev *dev);
+
 /**
  * @internal
  * Dump private info from device to a file.
@@ -1366,6 +1378,9 @@ struct eth_dev_ops {
 	/** Set IP reassembly configuration */
 	eth_ip_reassembly_conf_set_t ip_reassembly_conf_set;
 
+	/** Get supported header ptypes to split */
+	eth_buffer_split_supported_hdr_ptypes_get_t buffer_split_supported_hdr_ptypes_get;
+
 	/** Dump private info from device */
 	eth_dev_priv_dump_t eth_dev_priv_dump;
 
diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
index 4703ab0caf..79d1f9b993 100644
--- a/lib/ethdev/rte_ethdev.c
+++ b/lib/ethdev/rte_ethdev.c
@@ -6209,6 +6209,39 @@ rte_eth_tx_descriptor_dump(uint16_t port_id, uint16_t queue_id,
 						queue_id, offset, num, file));
 }
 
+int
+rte_eth_buffer_split_get_supported_hdr_ptypes(uint16_t port_id, uint32_t *ptypes, int num)
+{
+	int i, j;
+	struct rte_eth_dev *dev;
+	const uint32_t *all_types;
+
+	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -ENODEV);
+	dev = &rte_eth_devices[port_id];
+
+	if (ptypes == NULL && num > 0) {
+		RTE_ETHDEV_LOG(ERR,
+			"Cannot get ethdev port %u supported header protocol types to NULL when array size is non zero\n",
+			port_id);
+		return -EINVAL;
+	}
+
+	if (*dev->dev_ops->buffer_split_supported_hdr_ptypes_get == NULL)
+		return -ENOTSUP;
+	all_types = (*dev->dev_ops->buffer_split_supported_hdr_ptypes_get)(dev);
+
+	if (all_types == NULL)
+		return 0;
+
+	for (i = 0, j = 0; all_types[i] != RTE_PTYPE_UNKNOWN; ++i) {
+		if (j < num)
+			ptypes[j] = all_types[i];
+		j++;
+	}
+
+	return j;
+}
+
 RTE_LOG_REGISTER_DEFAULT(rte_eth_dev_logtype, INFO);
 
 RTE_INIT(ethdev_init_telemetry)
diff --git a/lib/ethdev/rte_ethdev.h b/lib/ethdev/rte_ethdev.h
index 8c4a35cc1f..f9da569179 100644
--- a/lib/ethdev/rte_ethdev.h
+++ b/lib/ethdev/rte_ethdev.h
@@ -6337,6 +6337,36 @@ rte_eth_tx_buffer(uint16_t port_id, uint16_t queue_id,
 	return rte_eth_tx_buffer_flush(port_id, queue_id, buffer);
 }
 
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice
+ *
+ * Get supported header protocols to split on Rx.
+ *
+ * When a packet type is announced to be split, it *must* be supported by
+ * the PMD. For instance, if eth-ipv4, eth-ipv4-udp is announced, the PMD must
+ * return the following packet types for these packets:
+ * - Ether/IPv4             -> RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4
+ * - Ether/IPv4/UDP         -> RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4 | RTE_PTYPE_L4_UDP
+ *
+ * @param port_id
+ *   The port identifier of the device.
+ * @param[out] ptypes
+ *   An array pointer to store supported protocol headers, allocated by caller.
+ *   These ptypes are composed with RTE_PTYPE_*.
+ * @param num
+ *   Size of the array pointed by param ptypes.
+ * @return
+ *   - (>=0) Number of supported ptypes. If the number of types exceeds num,
+ *           only num entries will be filled into the ptypes array, but the full
+ *           count of supported ptypes will be returned.
+ *   - (-ENOTSUP) if header protocol is not supported by device.
+ *   - (-ENODEV) if *port_id* invalid.
+ *   - (-EINVAL) if bad parameter.
+ */
+__rte_experimental
+int rte_eth_buffer_split_get_supported_hdr_ptypes(uint16_t port_id, uint32_t *ptypes, int num);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/ethdev/version.map b/lib/ethdev/version.map
index 3205556ce7..30b067e0b6 100644
--- a/lib/ethdev/version.map
+++ b/lib/ethdev/version.map
@@ -296,6 +296,7 @@ EXPERIMENTAL {
 	rte_flow_async_action_handle_query;
 	rte_mtr_meter_policy_get;
 	rte_mtr_meter_profile_get;
+	rte_eth_buffer_split_get_supported_hdr_ptypes;
 };
 
 INTERNAL {
-- 
2.25.1