[RFC 1/9] ethdev: add flex item modify field support

[Rongwei Liu <rongweil@nvidia.com>]

Add flex item as modify field destination.
Add "struct rte_flow_item_flex_handle *flex_handle" into
"struct rte_flow_action_modify_data" as union with existed
"level" member. This new member is dedicated for modifying
flex item.

Signed-off-by: Rongwei Liu <rongweil@nvidia.com>
---
 doc/guides/prog_guide/rte_flow.rst     | 36 ++++++++++++++------------
 doc/guides/rel_notes/release_22_03.rst |  4 +++
 lib/ethdev/rte_flow.h                  |  8 ++++--
 3 files changed, 29 insertions(+), 19 deletions(-)

diff --git a/doc/guides/prog_guide/rte_flow.rst b/doc/guides/prog_guide/rte_flow.rst
index 3e6242803d..ea20145224 100644
--- a/doc/guides/prog_guide/rte_flow.rst
+++ b/doc/guides/prog_guide/rte_flow.rst
@@ -2952,23 +2952,25 @@ value as sequence of bytes {xxx, xxx, 0x85, xxx, xxx, xxx}.
 
 .. table:: destination/source field definition
 
-   +---------------+----------------------------------------------------------+
-   | Field         | Value                                                    |
-   +===============+==========================================================+
-   | ``field``     | ID: packet field, mark, meta, tag, immediate, pointer    |
-   +---------------+----------------------------------------------------------+
-   | ``level``     | encapsulation level of a packet field or tag array index |
-   +---------------+----------------------------------------------------------+
-   | ``offset``    | number of bits to skip at the beginning                  |
-   +---------------+----------------------------------------------------------+
-   | ``value``     | immediate value buffer (source field only, not           |
-   |               | applicable to destination) for RTE_FLOW_FIELD_VALUE      |
-   |               | field type                                               |
-   +---------------+----------------------------------------------------------+
-   | ``pvalue``    | pointer to immediate value data (source field only, not  |
-   |               | applicable to destination) for RTE_FLOW_FIELD_POINTER    |
-   |               | field type                                               |
-   +---------------+----------------------------------------------------------+
+   +-----------------+----------------------------------------------------------+
+   | Field           | Value                                                    |
+   +=================+==========================================================+
+   | ``field``       | ID: packet field, mark, meta, tag, immediate, pointer    |
+   +-----------------+----------------------------------------------------------+
+   | ``level``       | encapsulation level of a packet field or tag array index |
+   +-----------------+----------------------------------------------------------+
+   | ``flex_handle`` | flex item handle of a packet field                       |
+   +-----------------+----------------------------------------------------------+
+   | ``offset``      | number of bits to skip at the beginning                  |
+   +-----------------+----------------------------------------------------------+
+   | ``value``       | immediate value buffer (source field only, not           |
+   |                 | applicable to destination) for RTE_FLOW_FIELD_VALUE      |
+   |                 | field type                                               |
+   +-----------------+----------------------------------------------------------+
+   | ``pvalue``      | pointer to immediate value data (source field only, not  |
+   |                 | applicable to destination) for RTE_FLOW_FIELD_POINTER    |
+   |                 | field type                                               |
+   +-----------------+----------------------------------------------------------+
 
 Action: ``CONNTRACK``
 ^^^^^^^^^^^^^^^^^^^^^
diff --git a/doc/guides/rel_notes/release_22_03.rst b/doc/guides/rel_notes/release_22_03.rst
index 0923707cb8..5fc5aff8a4 100644
--- a/doc/guides/rel_notes/release_22_03.rst
+++ b/doc/guides/rel_notes/release_22_03.rst
@@ -207,6 +207,10 @@ API Changes
 * ethdev: Old public macros and enumeration constants without ``RTE_ETH_`` prefix,
   which are kept for backward compatibility, are marked as deprecated.
 
+* ethdev: added a new field:
+
+  - modify flex item: ``rte_flow_action_modify_data.flex_handle``
+
 * cryptodev: The asymmetric session handling was modified to use a single
   mempool object. An API ``rte_cryptodev_asym_session_pool_create`` was added
   to create a mempool with element size big enough to hold the generic asymmetric
diff --git a/lib/ethdev/rte_flow.h b/lib/ethdev/rte_flow.h
index b60987db4b..d535722773 100644
--- a/lib/ethdev/rte_flow.h
+++ b/lib/ethdev/rte_flow.h
@@ -3528,6 +3528,7 @@ enum rte_flow_field_id {
 	RTE_FLOW_FIELD_IPV6_ECN,	/**< IPv6 ECN. */
 	RTE_FLOW_FIELD_GTP_PSC_QFI,	/**< GTP QFI. */
 	RTE_FLOW_FIELD_METER_COLOR,	/**< Meter color marker. */
+	RTE_FLOW_FIELD_FLEX_ITEM,       /**< Flex item. */
 };
 
 /**
@@ -3541,8 +3542,11 @@ struct rte_flow_action_modify_data {
 	RTE_STD_C11
 	union {
 		struct {
-			/** Encapsulation level or tag index. */
-			uint32_t level;
+			/**< Encapsulation level or tag index or flex item handle. */
+			union {
+				uint32_t level;
+				struct rte_flow_item_flex_handle *flex_handle;
+			};
 			/** Number of bits to skip from a field. */
 			uint32_t offset;
 		};
-- 
2.27.0