[PATCH 5/7] net/gve: RSS redirection table update support

[Joshua Washington <joshwash@google.com>]

This patch introduces support for updating the RSS redirection table in
the GVE PMD through the implementation of rss_reta_update and
rss_reta_query.

Due to an infrastructure limitation, the RSS hash key must be manually
configured before the redirection table can be updated or queried. The
redirection table is expected to be exactly 128 bytes.
---
 drivers/net/gve/gve_ethdev.c | 95 ++++++++++++++++++++++++++++++++++++
 1 file changed, 95 insertions(+)

diff --git a/drivers/net/gve/gve_ethdev.c b/drivers/net/gve/gve_ethdev.c
index 76405120b2..aa9b3d8372 100644
--- a/drivers/net/gve/gve_ethdev.c
+++ b/drivers/net/gve/gve_ethdev.c
@@ -770,6 +770,97 @@ gve_rss_hash_conf_get(struct rte_eth_dev *dev,
 	return 0;
 }
 
+static int
+gve_rss_reta_update(struct rte_eth_dev *dev,
+	struct rte_eth_rss_reta_entry64 *reta_conf, uint16_t reta_size)
+{
+	struct gve_priv *priv = dev->data->dev_private;
+	struct gve_rss_config gve_rss_conf;
+	int table_id;
+	int err;
+	int i;
+
+	// RSS key must be set before the redirection table can be set.
+	if (!priv->rss_config.key || priv->rss_config.key_size == 0) {
+		PMD_DRV_LOG(ERR, "RSS hash key msut be set before the "
+			"redirection table can be updated.");
+		return -ENOTSUP;
+	}
+
+	if (reta_size != GVE_RSS_INDIR_SIZE) {
+		PMD_DRV_LOG(ERR, "Redirection table must have %hu elements",
+			GVE_RSS_INDIR_SIZE);
+		return -EINVAL;
+	}
+
+	err = gve_init_rss_config_from_priv(priv, &gve_rss_conf);
+	if (err) {
+		PMD_DRV_LOG(ERR, "Error allocating new RSS config.");
+		return err;
+	}
+
+	table_id = 0;
+	for (i = 0; i < priv->rss_config.indir_size; i++) {
+		int table_entry = i % RTE_ETH_RETA_GROUP_SIZE;
+		if (reta_conf[table_id].mask & (1ULL << table_entry))
+			gve_rss_conf.indir[i] =
+				reta_conf[table_id].reta[table_entry];
+
+		if (table_entry == RTE_ETH_RETA_GROUP_SIZE - 1)
+			table_id ++;
+	}
+
+	err = gve_adminq_configure_rss(priv, &gve_rss_conf);
+	if (err)
+		PMD_DRV_LOG(ERR, "Problem configuring RSS with device.");
+	else
+		gve_update_priv_rss_config(priv, &gve_rss_conf);
+
+	gve_free_rss_config(&gve_rss_conf);
+	return err;
+}
+
+static int
+gve_rss_reta_query(struct rte_eth_dev *dev,
+	struct rte_eth_rss_reta_entry64 *reta_conf, uint16_t reta_size)
+{
+	struct gve_priv *priv = dev->data->dev_private;
+	int table_id;
+	int i;
+
+	if (!(dev->data->dev_conf.rxmode.offloads &
+		RTE_ETH_RX_OFFLOAD_RSS_HASH)) {
+		PMD_DRV_LOG(ERR, "RSS not configured.");
+		return -ENOTSUP;
+	}
+
+	// RSS key must be set before the redirection table can be queried.
+	if (!priv->rss_config.key) {
+		PMD_DRV_LOG(ERR, "RSS hash key must be set before the "
+			"redirection table can be initialized.");
+		return -ENOTSUP;
+	}
+
+	if (reta_size != priv->rss_config.indir_size) {
+		PMD_DRV_LOG(ERR, "RSS redirection table must have %d entries.",
+			priv->rss_config.indir_size);
+		return -EINVAL;
+	}
+
+	table_id = 0;
+	for (i = 0; i < priv->rss_config.indir_size; i++) {
+		int table_entry = i % RTE_ETH_RETA_GROUP_SIZE;
+		if (reta_conf[table_id].mask & (1ULL << table_entry))
+			reta_conf[table_id].reta[table_entry]
+				= priv->rss_config.indir[i];
+
+		if (table_entry == RTE_ETH_RETA_GROUP_SIZE - 1)
+			table_id ++;
+	}
+
+	return 0;
+}
+
 static const struct eth_dev_ops gve_eth_dev_ops = {
 	.dev_configure        = gve_dev_configure,
 	.dev_start            = gve_dev_start,
@@ -792,6 +883,8 @@ static const struct eth_dev_ops gve_eth_dev_ops = {
 	.xstats_get_names     = gve_xstats_get_names,
 	.rss_hash_update      = gve_rss_hash_update,
 	.rss_hash_conf_get    = gve_rss_hash_conf_get,
+	.reta_update          = gve_rss_reta_update,
+	.reta_query           = gve_rss_reta_query,
 };
 
 static const struct eth_dev_ops gve_eth_dev_ops_dqo = {
@@ -816,6 +909,8 @@ static const struct eth_dev_ops gve_eth_dev_ops_dqo = {
 	.xstats_get_names     = gve_xstats_get_names,
 	.rss_hash_update      = gve_rss_hash_update,
 	.rss_hash_conf_get    = gve_rss_hash_conf_get,
+	.reta_update          = gve_rss_reta_update,
+	.reta_query           = gve_rss_reta_query,
 };
 
 static void
-- 
2.43.0.429.g432eaa2c6b-goog