[dpdk-stable] [PATCH 17.11] examples/flow_filtering: fix flow create function

[Dekel Peled <dekelp@mellanox.com>]

Flow filtering example implements a simple flow rule creation and use.
The rule is created with ETH/VLAN/IPv4 pattern, but demonstrates only
IPv4 filtering, hence the VLAN item is redundant.
MLX5 PMD flow-rule validation was modified after the implementation of
this example, and now the example fails when trying to create rule.
Failure occurs due to the VLAN item.

This patch simplifies the example, removing the VLAN item from rule.
The documentation is modified accordingly.

Fixes: 4a3ef59a10c8 ("examples/flow_filtering: add simple demo of flow API")
Cc: orika@mellanox.com

Signed-off-by: Dekel Peled <dekelp@mellanox.com>
---
 doc/guides/sample_app_ug/flow_filtering.rst | 74 +++++++----------------------
 examples/flow_filtering/flow_blocks.c       | 39 ++++-----------
 2 files changed, 25 insertions(+), 88 deletions(-)

diff --git a/doc/guides/sample_app_ug/flow_filtering.rst b/doc/guides/sample_app_ug/flow_filtering.rst
index 725dcb4..6086632 100644
--- a/doc/guides/sample_app_ug/flow_filtering.rst
+++ b/doc/guides/sample_app_ug/flow_filtering.rst
@@ -81,7 +81,7 @@ applications and the Environment Abstraction Layer (EAL) options.
 Explanation
 -----------
 
-The example is build from 2 main files,
+The example is built from 2 files,
 ``main.c`` which holds the example logic and ``flow_blocks.c`` that holds the
 implementation for building the flow rule.
 
@@ -378,13 +378,9 @@ This function is located in the ``flow_blocks.c`` file.
    {
            struct rte_flow_attr attr;
            struct rte_flow_item pattern[MAX_PATTERN_NUM];
-           struct rte_flow_action action[MAX_PATTERN_NUM];
+           struct rte_flow_action action[MAX_ACTION_NUM];
            struct rte_flow *flow = NULL;
            struct rte_flow_action_queue queue = { .index = rx_q };
-           struct rte_flow_item_eth eth_spec;
-           struct rte_flow_item_eth eth_mask;
-           struct rte_flow_item_vlan vlan_spec;
-           struct rte_flow_item_vlan vlan_mask;
            struct rte_flow_item_ipv4 ip_spec;
            struct rte_flow_item_ipv4 ip_mask;
 
@@ -402,37 +398,19 @@ This function is located in the ``flow_blocks.c`` file.
             * create the action sequence.
             * one action only,  move packet to queue
             */
-
            action[0].type = RTE_FLOW_ACTION_TYPE_QUEUE;
            action[0].conf = &queue;
            action[1].type = RTE_FLOW_ACTION_TYPE_END;
 
            /*
-            * set the first level of the pattern (eth).
+            * set the first level of the pattern (ETH).
             * since in this example we just want to get the
             * ipv4 we set this level to allow all.
             */
-           memset(&eth_spec, 0, sizeof(struct rte_flow_item_eth));
-           memset(&eth_mask, 0, sizeof(struct rte_flow_item_eth));
-           eth_spec.type = 0;
-           eth_mask.type = 0;
            pattern[0].type = RTE_FLOW_ITEM_TYPE_ETH;
-           pattern[0].spec = &eth_spec;
-           pattern[0].mask = &eth_mask;
-
-           /*
-            * setting the second level of the pattern (vlan).
-            * since in this example we just want to get the
-            * ipv4 we also set this level to allow all.
-            */
-           memset(&vlan_spec, 0, sizeof(struct rte_flow_item_vlan));
-           memset(&vlan_mask, 0, sizeof(struct rte_flow_item_vlan));
-           pattern[1].type = RTE_FLOW_ITEM_TYPE_VLAN;
-           pattern[1].spec = &vlan_spec;
-           pattern[1].mask = &vlan_mask;
 
            /*
-            * setting the third level of the pattern (ip).
+            * setting the second level of the pattern (IP).
             * in this example this is the level we care about
             * so we set it according to the parameters.
             */
@@ -442,12 +420,12 @@ This function is located in the ``flow_blocks.c`` file.
            ip_mask.hdr.dst_addr = dest_mask;
            ip_spec.hdr.src_addr = htonl(src_ip);
            ip_mask.hdr.src_addr = src_mask;
-           pattern[2].type = RTE_FLOW_ITEM_TYPE_IPV4;
-           pattern[2].spec = &ip_spec;
-           pattern[2].mask = &ip_mask;
+           pattern[1].type = RTE_FLOW_ITEM_TYPE_IPV4;
+           pattern[1].spec = &ip_spec;
+           pattern[1].mask = &ip_mask;
 
            /* the final level must be always type end */
-           pattern[3].type = RTE_FLOW_ITEM_TYPE_END;
+           pattern[2].type = RTE_FLOW_ITEM_TYPE_END;
 
            int res = rte_flow_validate(port_id, &attr, pattern, action, error);
            if(!res)
@@ -462,14 +440,10 @@ The first part of the function is declaring the structures that will be used.
 
    struct rte_flow_attr attr;
    struct rte_flow_item pattern[MAX_PATTERN_NUM];
-   struct rte_flow_action action[MAX_PATTERN_NUM];
+   struct rte_flow_action action[MAX_ACTION_NUM];
    struct rte_flow *flow;
    struct rte_flow_error error;
    struct rte_flow_action_queue queue = { .index = rx_q };
-   struct rte_flow_item_eth eth_spec;
-   struct rte_flow_item_eth eth_mask;
-   struct rte_flow_item_vlan vlan_spec;
-   struct rte_flow_item_vlan vlan_mask;
    struct rte_flow_item_ipv4 ip_spec;
    struct rte_flow_item_ipv4 ip_mask;
 
@@ -489,33 +463,17 @@ the rule. In this case send the packet to queue.
    action[0].conf = &queue;
    action[1].type = RTE_FLOW_ACTION_TYPE_END;
 
-The forth part is responsible for creating the pattern and is build from
-number of step. In each step we build one level of the pattern starting with
+The fourth part is responsible for creating the pattern and is built from
+number of steps. In each step we build one level of the pattern starting with
 the lowest one.
 
 Setting the first level of the pattern ETH:
 
 .. code-block:: c
 
-   memset(&eth_spec, 0, sizeof(struct rte_flow_item_eth));
-   memset(&eth_mask, 0, sizeof(struct rte_flow_item_eth));
-   eth_spec.type = 0;
-   eth_mask.type = 0;
    pattern[0].type = RTE_FLOW_ITEM_TYPE_ETH;
-   pattern[0].spec = &eth_spec;
-   pattern[0].mask = &eth_mask;
-
-Setting the second level of the pattern VLAN:
-
-.. code-block:: c
-
-   memset(&vlan_spec, 0, sizeof(struct rte_flow_item_vlan));
-   memset(&vlan_mask, 0, sizeof(struct rte_flow_item_vlan));
-   pattern[1].type = RTE_FLOW_ITEM_TYPE_VLAN;
-   pattern[1].spec = &vlan_spec;
-   pattern[1].mask = &vlan_mask;
 
-Setting the third level ip:
+Setting the second level of the pattern IP:
 
 .. code-block:: c
 
@@ -525,15 +483,15 @@ Setting the third level ip:
    ip_mask.hdr.dst_addr = dest_mask;
    ip_spec.hdr.src_addr = htonl(src_ip);
    ip_mask.hdr.src_addr = src_mask;
-   pattern[2].type = RTE_FLOW_ITEM_TYPE_IPV4;
-   pattern[2].spec = &ip_spec;
-   pattern[2].mask = &ip_mask;
+   pattern[1].type = RTE_FLOW_ITEM_TYPE_IPV4;
+   pattern[1].spec = &ip_spec;
+   pattern[1].mask = &ip_mask;
 
 Closing the pattern part.
 
 .. code-block:: c
 
-   pattern[3].type = RTE_FLOW_ITEM_TYPE_END;
+   pattern[2].type = RTE_FLOW_ITEM_TYPE_END;
 
 The last part of the function is to validate the rule and create it.
 
diff --git a/examples/flow_filtering/flow_blocks.c b/examples/flow_filtering/flow_blocks.c
index f92df10..c1e482f 100644
--- a/examples/flow_filtering/flow_blocks.c
+++ b/examples/flow_filtering/flow_blocks.c
@@ -30,7 +30,8 @@
  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#define MAX_PATTERN_NUM		4
+#define MAX_PATTERN_NUM		3
+#define MAX_ACTION_NUM		2
 
 struct rte_flow *
 generate_ipv4_flow(uint8_t port_id, uint16_t rx_q,
@@ -69,13 +70,9 @@ struct rte_flow *
 {
 	struct rte_flow_attr attr;
 	struct rte_flow_item pattern[MAX_PATTERN_NUM];
-	struct rte_flow_action action[MAX_PATTERN_NUM];
+	struct rte_flow_action action[MAX_ACTION_NUM];
 	struct rte_flow *flow = NULL;
 	struct rte_flow_action_queue queue = { .index = rx_q };
-	struct rte_flow_item_eth eth_spec;
-	struct rte_flow_item_eth eth_mask;
-	struct rte_flow_item_vlan vlan_spec;
-	struct rte_flow_item_vlan vlan_mask;
 	struct rte_flow_item_ipv4 ip_spec;
 	struct rte_flow_item_ipv4 ip_mask;
 	int res;
@@ -94,37 +91,19 @@ struct rte_flow *
 	 * create the action sequence.
 	 * one action only,  move packet to queue
 	 */
-
 	action[0].type = RTE_FLOW_ACTION_TYPE_QUEUE;
 	action[0].conf = &queue;
 	action[1].type = RTE_FLOW_ACTION_TYPE_END;
 
 	/*
-	 * set the first level of the pattern (eth).
+	 * set the first level of the pattern (ETH).
 	 * since in this example we just want to get the
 	 * ipv4 we set this level to allow all.
 	 */
-	memset(&eth_spec, 0, sizeof(struct rte_flow_item_eth));
-	memset(&eth_mask, 0, sizeof(struct rte_flow_item_eth));
-	eth_spec.type = 0;
-	eth_mask.type = 0;
 	pattern[0].type = RTE_FLOW_ITEM_TYPE_ETH;
-	pattern[0].spec = &eth_spec;
-	pattern[0].mask = &eth_mask;
-
-	/*
-	 * setting the second level of the pattern (vlan).
-	 * since in this example we just want to get the
-	 * ipv4 we also set this level to allow all.
-	 */
-	memset(&vlan_spec, 0, sizeof(struct rte_flow_item_vlan));
-	memset(&vlan_mask, 0, sizeof(struct rte_flow_item_vlan));
-	pattern[1].type = RTE_FLOW_ITEM_TYPE_VLAN;
-	pattern[1].spec = &vlan_spec;
-	pattern[1].mask = &vlan_mask;
 
 	/*
-	 * setting the third level of the pattern (ip).
+	 * setting the second level of the pattern (IP).
 	 * in this example this is the level we care about
 	 * so we set it according to the parameters.
 	 */
@@ -134,12 +113,12 @@ struct rte_flow *
 	ip_mask.hdr.dst_addr = dest_mask;
 	ip_spec.hdr.src_addr = htonl(src_ip);
 	ip_mask.hdr.src_addr = src_mask;
-	pattern[2].type = RTE_FLOW_ITEM_TYPE_IPV4;
-	pattern[2].spec = &ip_spec;
-	pattern[2].mask = &ip_mask;
+	pattern[1].type = RTE_FLOW_ITEM_TYPE_IPV4;
+	pattern[1].spec = &ip_spec;
+	pattern[1].mask = &ip_mask;
 
 	/* the final level must be always type end */
-	pattern[3].type = RTE_FLOW_ITEM_TYPE_END;
+	pattern[2].type = RTE_FLOW_ITEM_TYPE_END;
 
 	res = rte_flow_validate(port_id, &attr, pattern, action, error);
 	if (!res)
-- 
1.8.3.1