[dpdk-dev] [PATCH v3] ethdev: add VLAN attributes to ETH and VLAN items

[Dekel Peled <dekelp@nvidia.com>]

This patch implements the change proposes in RFC [1], adding dedicated
fields to ETH and VLAN items structs, to clearly define the required
characteristic of a packet, and enable precise match criteria.
Documentation is updated accordingly.

[1] https://mails.dpdk.org/archives/dev/2020-August/177536.html

---
v2: fix checkpatch comment.
v3: updates description in comments and documentation.
---

Signed-off-by: Dekel Peled <dekelp@nvidia.com>
---
 doc/guides/prog_guide/rte_flow.rst     | 14 ++++++++++++--
 doc/guides/rel_notes/release_20_11.rst |  7 +++++++
 lib/librte_ethdev/rte_flow.h           | 18 +++++++++++++++---
 3 files changed, 34 insertions(+), 5 deletions(-)

diff --git a/doc/guides/prog_guide/rte_flow.rst b/doc/guides/prog_guide/rte_flow.rst
index 119b128..9ce3d04 100644
--- a/doc/guides/prog_guide/rte_flow.rst
+++ b/doc/guides/prog_guide/rte_flow.rst
@@ -908,12 +908,16 @@ order as on the wire.
 If the ``type`` field contains a TPID value, then only tagged packets with the
 specified TPID will match the pattern.
 Otherwise, only untagged packets will match the pattern.
-If the ``ETH`` item is the only item in the pattern, and the ``type`` field is
-not specified, then both tagged and untagged packets will match the pattern.
+The field ``vlan_exist`` can be used to match specific packet types, instead
+of using the ``type`` field.
+This can be used to match any type of tagged packets.
+If the ``type`` and ``vlan_exist`` fields are not specified, then both tagged
+and untagged packets will match the pattern.
 
 - ``dst``: destination MAC.
 - ``src``: source MAC.
 - ``type``: EtherType or TPID.
+- ``vlan_exist``: At least one VLAN exist in packet header.
 - Default ``mask`` matches destination and source addresses only.
 
 Item: ``VLAN``
@@ -926,9 +930,15 @@ The corresponding standard outer EtherType (TPID) values are
 preceding pattern item.
 If a ``VLAN`` item is present in the pattern, then only tagged packets will
 match the pattern.
+The field ``more_vlans_exist`` can be used to match specific packet types,
+instead of using the ``inner_type field``.
+This can be used to match any type of tagged packets.
+If the ``inner_type`` and ``more_vlans_exist`` fields are not specified,
+then any tagged packets will match the pattern.
 
 - ``tci``: tag control information.
 - ``inner_type``: inner EtherType or TPID.
+- ``more_vlans_exist``: at least one more VLAN exist in packet header, after this VLAN.
 - Default ``mask`` matches the VID part of TCI only (lower 12 bits).
 
 Item: ``IPV4``
diff --git a/doc/guides/rel_notes/release_20_11.rst b/doc/guides/rel_notes/release_20_11.rst
index 0b2a370..aceac07 100644
--- a/doc/guides/rel_notes/release_20_11.rst
+++ b/doc/guides/rel_notes/release_20_11.rst
@@ -198,6 +198,13 @@ API Changes
 
 * vhost: Moved vDPA APIs from experimental to stable.
 
+* ethdev: Added new field ``vlan_exist`` to structure ``rte_flow_item_eth``,
+  indicating that at least one VLAN exists in the packet header.
+
+* ethdev: Added new field ``more_vlans_exist`` to structure
+  ``rte_flow_item_vlan``, indicating that at least one more VLAN exists in
+  packet header, following this VLAN.
+
 * rawdev: Added a structure size parameter to the functions
   ``rte_rawdev_queue_setup()``, ``rte_rawdev_queue_conf_get()``,
   ``rte_rawdev_info_get()`` and ``rte_rawdev_configure()``,
diff --git a/lib/librte_ethdev/rte_flow.h b/lib/librte_ethdev/rte_flow.h
index da8bfa5..c3ac1e3 100644
--- a/lib/librte_ethdev/rte_flow.h
+++ b/lib/librte_ethdev/rte_flow.h
@@ -723,14 +723,18 @@ struct rte_flow_item_raw {
  * If the @p type field contains a TPID value, then only tagged packets with the
  * specified TPID will match the pattern.
  * Otherwise, only untagged packets will match the pattern.
- * If the @p ETH item is the only item in the pattern, and the @p type field
- * is not specified, then both tagged and untagged packets will match the
- * pattern.
+ * The field @p vlan_exist can be used to match specific packet types, instead
+ * of using the @p type field.
+ * This can be used to match any type of tagged packets.
+ * If the @p type and @p vlan_exist fields are not specified, then both tagged
+ * and untagged packets will match the pattern.
  */
 struct rte_flow_item_eth {
 	struct rte_ether_addr dst; /**< Destination MAC. */
 	struct rte_ether_addr src; /**< Source MAC. */
 	rte_be16_t type; /**< EtherType or TPID. */
+	uint32_t vlan_exist:1; /**< At least one VLAN exist in packet header. */
+	uint32_t reserved:31; /**< Reserved, must be zero. */
 };
 
 /** Default mask for RTE_FLOW_ITEM_TYPE_ETH. */
@@ -752,10 +756,18 @@ struct rte_flow_item_eth {
  * the preceding pattern item.
  * If a @p VLAN item is present in the pattern, then only tagged packets will
  * match the pattern.
+ * The field @p more_vlans_exist can be used to match specific packet types,
+ * instead of using the @p inner_type field.
+ * This can be used to match any type of tagged packets.
+ * If the @p inner_type and @p more_vlans_exist fields are not specified,
+ * then any tagged packets will match the pattern.
  */
 struct rte_flow_item_vlan {
 	rte_be16_t tci; /**< Tag control information. */
 	rte_be16_t inner_type; /**< Inner EtherType or TPID. */
+	uint32_t more_vlans_exist:1;
+	/**< At least one more VLAN exist in packet header, after this VLAN. */
+	uint32_t reserved:31; /**< Reserved, must be zero. */
 };
 
 /** Default mask for RTE_FLOW_ITEM_TYPE_VLAN. */
-- 
1.8.3.1