[PATCH v1 22/23] net/mlx5: add support for GENEVE VNI modify field

[Michael Baum <michaelba@nvidia.com>]

Add support for GENEVE VNI field modification.
The support is only using HW steering.

Signed-off-by: Michael Baum <michaelba@nvidia.com>
---
 doc/guides/nics/mlx5.rst               |  6 +++++-
 doc/guides/rel_notes/release_24_03.rst |  1 +
 drivers/net/mlx5/mlx5_flow_dv.c        |  4 +---
 drivers/net/mlx5/mlx5_flow_hw.c        | 12 ++++++++++--
 4 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/doc/guides/nics/mlx5.rst b/doc/guides/nics/mlx5.rst
index b946ce00c2..fceb5bd58b 100644
--- a/doc/guides/nics/mlx5.rst
+++ b/doc/guides/nics/mlx5.rst
@@ -577,7 +577,11 @@ Limitations
   - Modification of an arbitrary place in a packet via the special ``RTE_FLOW_FIELD_START`` Field ID is not supported.
   - Modification of the MPLS header is supported only in HWS and only to copy from,
     the encapsulation level is always 0.
-  - Modification of the 802.1Q Tag, VXLAN Network or GENEVE Network ID's is not supported.
+  - Modification of the 802.1Q Tag is not supported.
+  - Modification of VXLAN Network or GENEVE Network ID's is supported only for HW steering.
+  - Modification of GENEVE Network ID's is not supported when configured
+    ``FLEX_PARSER_PROFILE_ENABLE`` supports Geneve TLV options.
+    See :ref:`mlx5_firmware_config` for more flex parser information.
   - Encapsulation levels are not supported, can modify outermost header fields only.
   - Offsets cannot skip past the boundary of a field.
   - If the field type is ``RTE_FLOW_FIELD_MAC_TYPE``
diff --git a/doc/guides/rel_notes/release_24_03.rst b/doc/guides/rel_notes/release_24_03.rst
index bedef2a4c0..8a99d6bfa4 100644
--- a/doc/guides/rel_notes/release_24_03.rst
+++ b/doc/guides/rel_notes/release_24_03.rst
@@ -59,6 +59,7 @@ New Features
 
   * Added HW steering support for ``RTE_FLOW_ITEM_TYPE_GENEVE`` flow item.
   * Added HW steering support for ``RTE_FLOW_ITEM_TYPE_GENEVE_OPT`` flow item.
+  * Added HW steering support for modify field ``RTE_FLOW_FIELD_GENEVE_VNI`` flow action.
 
 
 Removed Items
diff --git a/drivers/net/mlx5/mlx5_flow_dv.c b/drivers/net/mlx5/mlx5_flow_dv.c
index 72e0d82e7b..bb3d7ddc3c 100644
--- a/drivers/net/mlx5/mlx5_flow_dv.c
+++ b/drivers/net/mlx5/mlx5_flow_dv.c
@@ -1881,6 +1881,7 @@ mlx5_flow_field_id_to_modify_info
 			info[idx].offset = off_be;
 		break;
 	case RTE_FLOW_FIELD_VXLAN_VNI:
+	case RTE_FLOW_FIELD_GENEVE_VNI:
 		MLX5_ASSERT(data->offset + width <= 24);
 		/* VNI is on bits 31-8 of TUNNEL_HDR_DW_1. */
 		off_be = 24 - (data->offset + width) + 8;
@@ -1891,9 +1892,6 @@ mlx5_flow_field_id_to_modify_info
 		else
 			info[idx].offset = off_be;
 		break;
-	case RTE_FLOW_FIELD_GENEVE_VNI:
-		/* not supported yet*/
-		break;
 	case RTE_FLOW_FIELD_GTP_TEID:
 		MLX5_ASSERT(data->offset + width <= 32);
 		off_be = 32 - (data->offset + width);
diff --git a/drivers/net/mlx5/mlx5_flow_hw.c b/drivers/net/mlx5/mlx5_flow_hw.c
index 7c786c432f..22ac4e0a7c 100644
--- a/drivers/net/mlx5/mlx5_flow_hw.c
+++ b/drivers/net/mlx5/mlx5_flow_hw.c
@@ -4952,6 +4952,8 @@ flow_hw_validate_action_modify_field(struct rte_eth_dev *dev,
 {
 	const struct rte_flow_action_modify_field *action_conf = action->conf;
 	const struct rte_flow_action_modify_field *mask_conf = mask->conf;
+	struct mlx5_priv *priv = dev->data->dev_private;
+	struct mlx5_hca_attr *attr = &priv->sh->cdev->config.hca_attr;
 	int ret;
 
 	if (!mask_conf)
@@ -5047,10 +5049,16 @@ flow_hw_validate_action_modify_field(struct rte_eth_dev *dev,
 		return rte_flow_error_set(error, EINVAL,
 				RTE_FLOW_ERROR_TYPE_ACTION, action,
 				"modifying vlan_type is not supported");
-	if (flow_hw_modify_field_is_used(action_conf, RTE_FLOW_FIELD_GENEVE_VNI))
+	/**
+	 * Geneve VNI modification is supported only when Geneve header is
+	 * parsed natively. When GENEVE options are supported, they both Geneve
+	 * and options headers are parsed as a flex parser.
+	 */
+	if (flow_hw_modify_field_is_used(action_conf, RTE_FLOW_FIELD_GENEVE_VNI) &&
+	    attr->geneve_tlv_opt)
 		return rte_flow_error_set(error, EINVAL,
 				RTE_FLOW_ERROR_TYPE_ACTION, action,
-				"modifying Geneve VNI is not supported");
+				"modifying Geneve VNI is not supported when GENEVE opt is supported");
 	/* Due to HW bug, tunnel MPLS header is read only. */
 	if (action_conf->dst.field == RTE_FLOW_FIELD_MPLS)
 		return rte_flow_error_set(error, EINVAL,
-- 
2.25.1