[dpdk-dev] [PATCH 3/4] net/mlx5: prepare to add E-switch rule flags check

[Slava Ovsiienko]

The tc flower filter rules are used to control E-switch from
the application side. In order to gain garanteed rule hardware
offload the skip_sw flag should be specified while applying the
rule. But some tc rules is rejected by kernel if skip_sw flag
is set by design. Currently this regards VXLAN tunneling rules,
which are applied to special VXLAN virtual devices. Albeit these
rules are applied with skip_sw flag reset kernel tries to
perform hardware offload. If kernel succeeded the in_hw flag
is set in rule properties and application should check this
flag to get know whether the applied rule is actually hardware
offloaded.

This patch prepares for the rule flags query and check in_hw flag.
The driver checks only the rules with skip_sw flag reset, so we
need to test the actual flags of rule is being applied. The pointer
to flags field into translated rule is introduced and flags are
tested directly in the rule body. It is more reliable than save and
check flags copy.

Also patch swaps the flow_tcf_apply() and flow_tcf_remove(),
we are going to call flow_tcf_remove() from flow_tcf_appy() if
no in_hw flag set found in applied rule.

Signed-off-by: Viacheslav Ovsiienko <viacheslavo at mellanox.com>
---
 drivers/net/mlx5/mlx5_flow.h     |  1 +
 drivers/net/mlx5/mlx5_flow_tcf.c | 82 +++++++++++++++++++++-------------------
 2 files changed, 44 insertions(+), 39 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_flow.h b/drivers/net/mlx5/mlx5_flow.h
index 51ab47f..57b312e 100644
--- a/drivers/net/mlx5/mlx5_flow.h
+++ b/drivers/net/mlx5/mlx5_flow.h
@@ -219,6 +219,7 @@ struct mlx5_flow_dv {
 struct mlx5_flow_tcf {
 	struct nlmsghdr *nlh;
 	struct tcmsg *tcm;
+	uint32_t *ptc_flags; /**< tc rule applied flags. */
 	union { /**< Tunnel encap/decap descriptor. */
 		struct flow_tcf_tunnel_hdr *tunnel;
 		struct flow_tcf_vxlan_decap *vxlan_decap;
diff --git a/drivers/net/mlx5/mlx5_flow_tcf.c b/drivers/net/mlx5/mlx5_flow_tcf.c
index 4d154b6..5bfb2d8 100644
--- a/drivers/net/mlx5/mlx5_flow_tcf.c
+++ b/drivers/net/mlx5/mlx5_flow_tcf.c
@@ -160,6 +160,9 @@ struct tc_tunnel_key {
 #ifndef TCA_CLS_FLAGS_SKIP_SW
 #define TCA_CLS_FLAGS_SKIP_SW (1 << 1)
 #endif
+#ifndef TCA_CLS_FLAGS_IN_HW
+#define TCA_CLS_FLAGS_IN_HW (1 << 2)
+#endif
 #ifndef HAVE_TCA_CHAIN
 #define TCA_CHAIN 11
 #endif
@@ -3699,6 +3702,8 @@ struct pedit_parser {
 	assert(na_flower);
 	assert(na_flower_act);
 	mnl_attr_nest_end(nlh, na_flower_act);
+	dev_flow->tcf.ptc_flags = mnl_attr_get_payload
+					(mnl_nlmsg_get_payload_tail(nlh));
 	mnl_attr_put_u32(nlh, TCA_FLOWER_FLAGS,	decap.vxlan ?
 						0 : TCA_CLS_FLAGS_SKIP_SW);
 	mnl_attr_nest_end(nlh, na_flower);
@@ -5077,6 +5082,44 @@ struct tcf_nlcb_context {
 	pthread_mutex_unlock(&vtep_list_mutex);
 }
 
+/**
+ * Remove flow from E-Switch by sending Netlink message.
+ *
+ * @param[in] dev
+ *   Pointer to Ethernet device.
+ * @param[in, out] flow
+ *   Pointer to the sub flow.
+ */
+static void
+flow_tcf_remove(struct rte_eth_dev *dev, struct rte_flow *flow)
+{
+	struct priv *priv = dev->data->dev_private;
+	struct mlx5_flow_tcf_context *ctx = priv->tcf_context;
+	struct mlx5_flow *dev_flow;
+	struct nlmsghdr *nlh;
+
+	if (!flow)
+		return;
+	dev_flow = LIST_FIRST(&flow->dev_flows);
+	if (!dev_flow)
+		return;
+	/* E-Switch flow can't be expanded. */
+	assert(!LIST_NEXT(dev_flow, next));
+	if (dev_flow->tcf.applied) {
+		nlh = dev_flow->tcf.nlh;
+		nlh->nlmsg_type = RTM_DELTFILTER;
+		nlh->nlmsg_flags = NLM_F_REQUEST;
+		flow_tcf_nl_ack(ctx, nlh, NULL, NULL);
+		if (dev_flow->tcf.tunnel) {
+			assert(dev_flow->tcf.tunnel->vtep);
+			flow_tcf_vtep_release(ctx,
+				dev_flow->tcf.tunnel->vtep,
+				dev_flow);
+			dev_flow->tcf.tunnel->vtep = NULL;
+		}
+		dev_flow->tcf.applied = 0;
+	}
+}
 
 /**
  * Apply flow to E-Switch by sending Netlink message.
@@ -5145,45 +5188,6 @@ struct tcf_nlcb_context {
 }
 
 /**
- * Remove flow from E-Switch by sending Netlink message.
- *
- * @param[in] dev
- *   Pointer to Ethernet device.
- * @param[in, out] flow
- *   Pointer to the sub flow.
- */
-static void
-flow_tcf_remove(struct rte_eth_dev *dev, struct rte_flow *flow)
-{
-	struct priv *priv = dev->data->dev_private;
-	struct mlx5_flow_tcf_context *ctx = priv->tcf_context;
-	struct mlx5_flow *dev_flow;
-	struct nlmsghdr *nlh;
-
-	if (!flow)
-		return;
-	dev_flow = LIST_FIRST(&flow->dev_flows);
-	if (!dev_flow)
-		return;
-	/* E-Switch flow can't be expanded. */
-	assert(!LIST_NEXT(dev_flow, next));
-	if (dev_flow->tcf.applied) {
-		nlh = dev_flow->tcf.nlh;
-		nlh->nlmsg_type = RTM_DELTFILTER;
-		nlh->nlmsg_flags = NLM_F_REQUEST;
-		flow_tcf_nl_ack(ctx, nlh, NULL, NULL);
-		if (dev_flow->tcf.tunnel) {
-			assert(dev_flow->tcf.tunnel->vtep);
-			flow_tcf_vtep_release(ctx,
-				dev_flow->tcf.tunnel->vtep,
-				dev_flow);
-			dev_flow->tcf.tunnel->vtep = NULL;
-		}
-		dev_flow->tcf.applied = 0;
-	}
-}
-
-/**
  * Remove flow from E-Switch and release resources of the device flow.
  *
  * @param[in] dev
-- 
1.8.3.1