[PATCH v4 4/6] ethdev: add mark flow item to flow item types

[Declan Doherty <declan.doherty@intel.com>]

Introduces a new action type RTE_FLOW_ITEM_TYPE_MARK which enables
flow patterns to specify arbitrary integer values to match aginst
which are set by the RTE_FLOW_ACTION_TYPE_MARK action in a 
previously matched flow from a higher prioriry group.

Signed-off-by: Declan Doherty <declan.doherty@intel.com>
---
 doc/guides/prog_guide/rte_flow.rst | 28 ++++++++++++++++++++++++++++
 lib/librte_ether/rte_flow.h        | 24 ++++++++++++++++++++++++
 2 files changed, 52 insertions(+)

diff --git a/doc/guides/prog_guide/rte_flow.rst b/doc/guides/prog_guide/rte_flow.rst
index 325010544..6f23ad909 100644
--- a/doc/guides/prog_guide/rte_flow.rst
+++ b/doc/guides/prog_guide/rte_flow.rst
@@ -598,6 +598,34 @@ associated with a port_id should be retrieved by other means.
    | ``mask`` | ``index`` | zeroed to match any port index |
    +----------+-----------+--------------------------------+
 
+Item: ``MARK``
+^^^^^^^^^^^^^^
+
+Matches packets coming from a previously matched flow in a higher priority group
+with an arbitrary integer value which was set using the ``MARK`` action in the
+previously matched rule.
+
+This item can only specified once as a match criteria as the ``MARK`` action can
+only be specified once in a flow action.
+
+Note the value of MARK field is arbitrary and application defined.
+
+- Default ``mask`` matches any integer value.
+
+.. _table_rte_flow_item_mark:
+
+.. table:: MARK
+
+   +----------+----------+---------------------------+
+   | Field    | Subfield | Value                     |
+   +==========+==========+===========================+
+   | ``spec`` | ``id``   | integer value             |
+   +----------+--------------------------------------+
+   | ``last`` | ``id``   | upper range value         |
+   +----------+----------+---------------------------+
+   | ``mask`` | ``id``   | zeroed to match any value |
+   +----------+------- --+---------------------------+
+
 Data matching item types
 ~~~~~~~~~~~~~~~~~~~~~~~~
 
diff --git a/lib/librte_ether/rte_flow.h b/lib/librte_ether/rte_flow.h
index 91544f62b..56e262a23 100644
--- a/lib/librte_ether/rte_flow.h
+++ b/lib/librte_ether/rte_flow.h
@@ -323,6 +323,13 @@ enum rte_flow_item_type {
 	 * See struct rte_flow_item_geneve.
 	 */
 	RTE_FLOW_ITEM_TYPE_GENEVE,
+
+	/**
+	 * Matches specified mark field.
+	 *
+	 * See struct rte_flow_item_mark.
+	 */
+	RTE_FLOW_ITEM_TYPE_MARK
 };
 
 /**
@@ -814,6 +821,23 @@ static const struct rte_flow_item_geneve rte_flow_item_geneve_mask = {
 };
 #endif
 
+/**
+ * RTE_FLOW_ITEM_TYPE_MARK
+ *
+ * Allow arbitrary integer value set using MARK action in a flow rule in a
+ * higher priority group to be matched against in flow rule in a lower
+ * priority group.
+ *
+ * This value is arbitrary and application-defined. Maximum allowed value
+ * depends on the underlying implementation.
+ *
+ * Depending on the underlying implementation the MARK item may be supported in
+ * the physical device, virtually in logical groups in the PMD or not at all.
+ */
+struct rte_flow_item_mark {
+	uint32_t id; /**< Integer value to match against. */
+};
+
 /**
  * Matching pattern item definition.
  *
-- 
2.14.3