| | ``index`` | field is ignored |
+----------+-----------+---------------------------------------+
-ata matching item types
-~~~~~~~~~~~~~~~~~~~~~~~
+Item: ``META``
+^^^^^^^^^^^^^^^^^
+
+Matches 32 bit metadata item set.
+
+On egress, metadata can be set either by mbuf metadata field with
+PKT_TX_METADATA flag or ``SET_META`` action. On ingress, ``SET_META``
+action sets metadata for a packet and the metadata will be reported via
+``metadata`` dynamic field of ``rte_mbuf`` with PKT_RX_DYNF_METADATA flag.
+
+- Default ``mask`` matches the specified Rx metadata value.
+
+.. _table_rte_flow_item_meta:
+
+.. table:: META
+
+ +----------+----------+---------------------------------------+
+ | Field | Subfield | Value |
+ +==========+==========+=======================================+
+ | ``spec`` | ``data`` | 32 bit metadata value |
+ +----------+----------+---------------------------------------+
+ | ``last`` | ``data`` | upper range value |
+ +----------+----------+---------------------------------------+
+ | ``mask`` | ``data`` | bit-mask applies to "spec" and "last" |
+ +----------+----------+---------------------------------------+
+
+Data matching item types
+~~~~~~~~~~~~~~~~~~~~~~~~
Most of these are basically protocol header definitions with associated
bit-masks. They must be specified (stacked) from lowest to highest protocol
- ``proto_id``: PPP protocol identifier.
- Default ``mask`` matches proto_id only.
-
-.. _table_rte_flow_item_meta:
-
-.. table:: META
-
- +----------+----------+---------------------------------------+
- | Field | Subfield | Value |
- +==========+==========+=======================================+
- | ``spec`` | ``data`` | 32 bit metadata value |
- +----------+--------------------------------------------------+
- | ``last`` | ``data`` | upper range value |
- +----------+----------+---------------------------------------+
- | ``mask`` | ``data`` | bit-mask applies to "spec" and "last" |
- +----------+----------+---------------------------------------+
-
Item: ``NSH``
^^^^^^^^^^^^^
| ``index`` | index of tag to set |
+-----------+----------------------------+
+Action: ``SET_META``
+^^^^^^^^^^^^^^^^^^^^^^^
+
+Set metadata. Item ``META`` matches metadata.
+
+Metadata set by mbuf metadata field with PKT_TX_METADATA flag on egress will be
+overridden by this action. On ingress, the metadata will be carried by
+``metadata`` dynamic field of ``rte_mbuf`` which can be accessed by
+``RTE_FLOW_DYNF_METADATA()``. PKT_RX_DYNF_METADATA flag will be set along
+with the data.
+
+The mbuf dynamic field must be registered by calling
+``rte_flow_dynf_metadata_register()`` prior to use ``SET_META`` action.
+
+Altering partial bits is supported with ``mask``. For bits which have never been
+set, unpredictable value will be seen depending on driver implementation. For
+loopback/hairpin packet, metadata set on Rx/Tx may or may not be propagated to
+the other path depending on HW capability.
+
+.. _table_rte_flow_action_set_meta:
+
+.. table:: SET_META
+
+ +----------+----------------------------+
+ | Field | Value |
+ +==========+============================+
+ | ``data`` | 32 bit metadata value |
+ +----------+----------------------------+
+ | ``mask`` | bit-mask applies to "data" |
+ +----------+----------------------------+
+
Negative types
~~~~~~~~~~~~~~