iavf: enable symmetric-xor RSS for Toeplitz hash function

Allow the user to set the symmetric Toeplitz hash function via:

    # ethtool -X eth0 hfunc toeplitz symmetric-xor

The driver will reject any new RSS configuration if a field other than
(IP src/dst and L4 src/dst ports) is requested for hashing.

The symmetric RSS will not be supported on PFs not advertising the ADV RSS
Offload flag (ADV_RSS_SUPPORT()), for example the E700 series (i40e).

Reviewed-by: Madhu Chittim <madhu.chittim@intel.com>
Signed-off-by: Ahmed Zaki <ahmed.zaki@intel.com>
Link: https://lore.kernel.org/r/20231213003321.605376-9-ahmed.zaki@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

6 files changed, 85 insertions, 8 deletions

diff --git a/drivers/net/ethernet/intel/iavf/iavf.h b/drivers/net/ethernet/intel/iavf/iavf.h
index e7ab89dc883a..f83fbcc72075 100644
--- a/drivers/net/ethernet/intel/iavf/iavf.h
+++ b/drivers/net/ethernet/intel/iavf/iavf.h
@@ -312,7 +312,8 @@ struct iavf_adapter {
 #define IAVF_FLAG_AQ_SET_HENA			BIT_ULL(12)
 #define IAVF_FLAG_AQ_SET_RSS_KEY		BIT_ULL(13)
 #define IAVF_FLAG_AQ_SET_RSS_LUT		BIT_ULL(14)
-#define IAVF_FLAG_AQ_CONFIGURE_PROMISC_MODE	BIT_ULL(15)
+#define IAVF_FLAG_AQ_SET_RSS_HFUNC		BIT_ULL(15)
+#define IAVF_FLAG_AQ_CONFIGURE_PROMISC_MODE	BIT_ULL(16)
 #define IAVF_FLAG_AQ_ENABLE_VLAN_STRIPPING	BIT_ULL(19)
 #define IAVF_FLAG_AQ_DISABLE_VLAN_STRIPPING	BIT_ULL(20)
 #define IAVF_FLAG_AQ_ENABLE_CHANNELS		BIT_ULL(21)
@@ -414,6 +415,7 @@ struct iavf_adapter {
 	struct iavf_vsi vsi;
 	u32 aq_wait_count;
 	/* RSS stuff */
+	enum virtchnl_rss_algorithm hfunc;
 	u64 hena;
 	u16 rss_key_size;
 	u16 rss_lut_size;
@@ -539,6 +541,7 @@ void iavf_get_hena(struct iavf_adapter *adapter);
 void iavf_set_hena(struct iavf_adapter *adapter);
 void iavf_set_rss_key(struct iavf_adapter *adapter);
 void iavf_set_rss_lut(struct iavf_adapter *adapter);
+void iavf_set_rss_hfunc(struct iavf_adapter *adapter);
 void iavf_enable_vlan_stripping(struct iavf_adapter *adapter);
 void iavf_disable_vlan_stripping(struct iavf_adapter *adapter);
 void iavf_virtchnl_completion(struct iavf_adapter *adapter,
diff --git a/drivers/net/ethernet/intel/iavf/iavf_adv_rss.c b/drivers/net/ethernet/intel/iavf/iavf_adv_rss.c
index 6edbf134b73f..a9e1da35e248 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_adv_rss.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_adv_rss.c
@@ -95,17 +95,21 @@ iavf_fill_adv_rss_sctp_hdr(struct virtchnl_proto_hdr *hdr, u64 hash_flds)
  * @rss_cfg: the virtchnl message to be filled with RSS configuration setting
  * @packet_hdrs: the RSS configuration protocol header types
  * @hash_flds: the RSS configuration protocol hash fields
+ * @symm: if true, symmetric hash is required
  *
  * Returns 0 if the RSS configuration virtchnl message is filled successfully
  */
 int
 iavf_fill_adv_rss_cfg_msg(struct virtchnl_rss_cfg *rss_cfg,
-			  u32 packet_hdrs, u64 hash_flds)
+			  u32 packet_hdrs, u64 hash_flds, bool symm)
 {
 	struct virtchnl_proto_hdrs *proto_hdrs = &rss_cfg->proto_hdrs;
 	struct virtchnl_proto_hdr *hdr;
 
-	rss_cfg->rss_algorithm = VIRTCHNL_RSS_ALG_TOEPLITZ_ASYMMETRIC;
+	if (symm)
+		rss_cfg->rss_algorithm = VIRTCHNL_RSS_ALG_TOEPLITZ_SYMMETRIC;
+	else
+		rss_cfg->rss_algorithm = VIRTCHNL_RSS_ALG_TOEPLITZ_ASYMMETRIC;
 
 	proto_hdrs->tunnel_level = 0;	/* always outer layer */
 
diff --git a/drivers/net/ethernet/intel/iavf/iavf_adv_rss.h b/drivers/net/ethernet/intel/iavf/iavf_adv_rss.h
index 4d3be11af7aa..e31eb2afebea 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_adv_rss.h
+++ b/drivers/net/ethernet/intel/iavf/iavf_adv_rss.h
@@ -80,13 +80,14 @@ struct iavf_adv_rss {
 
 	u32 packet_hdrs;
 	u64 hash_flds;
+	bool symm;
 
 	struct virtchnl_rss_cfg cfg_msg;
 };
 
 int
 iavf_fill_adv_rss_cfg_msg(struct virtchnl_rss_cfg *rss_cfg,
-			  u32 packet_hdrs, u64 hash_flds);
+			  u32 packet_hdrs, u64 hash_flds, bool symm);
 struct iavf_adv_rss *
 iavf_find_adv_rss_cfg_by_hdrs(struct iavf_adapter *adapter, u32 packet_hdrs);
 void
diff --git a/drivers/net/ethernet/intel/iavf/iavf_ethtool.c b/drivers/net/ethernet/intel/iavf/iavf_ethtool.c
index c376a489e4c2..f147743792fb 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_ethtool.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_ethtool.c
@@ -1529,11 +1529,12 @@ static u32 iavf_adv_rss_parse_hdrs(struct ethtool_rxnfc *cmd)
 /**
  * iavf_adv_rss_parse_hash_flds - parses hash fields from RSS hash input
  * @cmd: ethtool rxnfc command
+ * @symm: true if Symmetric Topelitz is set
  *
  * This function parses the rxnfc command and returns intended hash fields for
  * RSS configuration
  */
-static u64 iavf_adv_rss_parse_hash_flds(struct ethtool_rxnfc *cmd)
+static u64 iavf_adv_rss_parse_hash_flds(struct ethtool_rxnfc *cmd, bool symm)
 {
 	u64 hfld = IAVF_ADV_RSS_HASH_INVALID;
 
@@ -1605,17 +1606,20 @@ iavf_set_adv_rss_hash_opt(struct iavf_adapter *adapter,
 	struct iavf_adv_rss *rss_old, *rss_new;
 	bool rss_new_add = false;
 	int count = 50, err = 0;
+	bool symm = false;
 	u64 hash_flds;
 	u32 hdrs;
 
 	if (!ADV_RSS_SUPPORT(adapter))
 		return -EOPNOTSUPP;
 
+	symm = !!(adapter->hfunc == VIRTCHNL_RSS_ALG_TOEPLITZ_SYMMETRIC);
+
 	hdrs = iavf_adv_rss_parse_hdrs(cmd);
 	if (hdrs == IAVF_ADV_RSS_FLOW_SEG_HDR_NONE)
 		return -EINVAL;
 
-	hash_flds = iavf_adv_rss_parse_hash_flds(cmd);
+	hash_flds = iavf_adv_rss_parse_hash_flds(cmd, symm);
 	if (hash_flds == IAVF_ADV_RSS_HASH_INVALID)
 		return -EINVAL;
 
@@ -1623,7 +1627,8 @@ iavf_set_adv_rss_hash_opt(struct iavf_adapter *adapter,
 	if (!rss_new)
 		return -ENOMEM;
 
-	if (iavf_fill_adv_rss_cfg_msg(&rss_new->cfg_msg, hdrs, hash_flds)) {
+	if (iavf_fill_adv_rss_cfg_msg(&rss_new->cfg_msg, hdrs, hash_flds,
+				      symm)) {
 		kfree(rss_new);
 		return -EINVAL;
 	}
@@ -1642,9 +1647,11 @@ iavf_set_adv_rss_hash_opt(struct iavf_adapter *adapter,
 	if (rss_old) {
 		if (rss_old->state != IAVF_ADV_RSS_ACTIVE) {
 			err = -EBUSY;
-		} else if (rss_old->hash_flds != hash_flds) {
+		} else if (rss_old->hash_flds != hash_flds ||
+			   rss_old->symm != symm) {
 			rss_old->state = IAVF_ADV_RSS_ADD_REQUEST;
 			rss_old->hash_flds = hash_flds;
+			rss_old->symm = symm;
 			memcpy(&rss_old->cfg_msg, &rss_new->cfg_msg,
 			       sizeof(rss_new->cfg_msg));
 		} else {
@@ -1655,6 +1662,7 @@ iavf_set_adv_rss_hash_opt(struct iavf_adapter *adapter,
 		rss_new->state = IAVF_ADV_RSS_ADD_REQUEST;
 		rss_new->packet_hdrs = hdrs;
 		rss_new->hash_flds = hash_flds;
+		rss_new->symm = symm;
 		list_add_tail(&rss_new->list, &adapter->adv_rss_list_head);
 	}
 	spin_unlock_bh(&adapter->adv_rss_lock);
@@ -1905,6 +1913,9 @@ static int iavf_get_rxfh(struct net_device *netdev,
 	u16 i;
 
 	rxfh->hfunc = ETH_RSS_HASH_TOP;
+	if (adapter->hfunc == VIRTCHNL_RSS_ALG_TOEPLITZ_SYMMETRIC)
+		rxfh->input_xfrm |= RXH_XFRM_SYM_XOR;
+
 	if (rxfh->key)
 		memcpy(rxfh->key, adapter->rss_key, adapter->rss_key_size);
 
@@ -1937,6 +1948,18 @@ static int iavf_set_rxfh(struct net_device *netdev,
 	    rxfh->hfunc != ETH_RSS_HASH_TOP)
 		return -EOPNOTSUPP;
 
+	if ((rxfh->input_xfrm & RXH_XFRM_SYM_XOR) &&
+	    adapter->hfunc != VIRTCHNL_RSS_ALG_TOEPLITZ_SYMMETRIC) {
+		if (!ADV_RSS_SUPPORT(adapter))
+			return -EOPNOTSUPP;
+		adapter->hfunc = VIRTCHNL_RSS_ALG_TOEPLITZ_SYMMETRIC;
+		adapter->aq_required |= IAVF_FLAG_AQ_SET_RSS_HFUNC;
+	} else if (!(rxfh->input_xfrm & RXH_XFRM_SYM_XOR) &&
+		    adapter->hfunc != VIRTCHNL_RSS_ALG_TOEPLITZ_ASYMMETRIC) {
+		adapter->hfunc = VIRTCHNL_RSS_ALG_TOEPLITZ_ASYMMETRIC;
+		adapter->aq_required |= IAVF_FLAG_AQ_SET_RSS_HFUNC;
+	}
+
 	if (!rxfh->key && !rxfh->indir)
 		return 0;
 
@@ -1955,6 +1978,7 @@ static int iavf_set_rxfh(struct net_device *netdev,
 static const struct ethtool_ops iavf_ethtool_ops = {
 	.supported_coalesce_params = ETHTOOL_COALESCE_USECS |
 				     ETHTOOL_COALESCE_USE_ADAPTIVE,
+	.cap_rss_sym_xor_supported = true,
 	.get_drvinfo		= iavf_get_drvinfo,
 	.get_link		= ethtool_op_get_link,
 	.get_ringparam		= iavf_get_ringparam,
diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
index 06a87030c163..0b3b33acf1bd 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -2166,6 +2166,10 @@ static int iavf_process_aq_command(struct iavf_adapter *adapter)
 		iavf_set_rss_lut(adapter);
 		return 0;
 	}
+	if (adapter->aq_required & IAVF_FLAG_AQ_SET_RSS_HFUNC) {
+		iavf_set_rss_hfunc(adapter);
+		return 0;
+	}
 
 	if (adapter->aq_required & IAVF_FLAG_AQ_CONFIGURE_PROMISC_MODE) {
 		iavf_set_promiscuous(adapter);
diff --git a/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c b/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c
index 64c4443dbef9..64a351e70a56 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_virtchnl.c
@@ -1142,6 +1142,34 @@ void iavf_set_rss_lut(struct iavf_adapter *adapter)
 }
 
 /**
+ * iavf_set_rss_hfunc
+ * @adapter: adapter structure
+ *
+ * Request the PF to set our RSS Hash function
+ **/
+void iavf_set_rss_hfunc(struct iavf_adapter *adapter)
+{
+	struct virtchnl_rss_hfunc *vrh;
+	int len = sizeof(*vrh);
+
+	if (adapter->current_op != VIRTCHNL_OP_UNKNOWN) {
+		/* bail because we already have a command pending */
+		dev_err(&adapter->pdev->dev, "Cannot set RSS Hash function, command %d pending\n",
+			adapter->current_op);
+		return;
+	}
+	vrh = kzalloc(len, GFP_KERNEL);
+	if (!vrh)
+		return;
+	vrh->vsi_id = adapter->vsi.id;
+	vrh->rss_algorithm = adapter->hfunc;
+	adapter->current_op = VIRTCHNL_OP_CONFIG_RSS_HFUNC;
+	adapter->aq_required &= ~IAVF_FLAG_AQ_SET_RSS_HFUNC;
+	iavf_send_pf_msg(adapter, VIRTCHNL_OP_CONFIG_RSS_HFUNC, (u8 *)vrh, len);
+	kfree(vrh);
+}
+
+/**
  * iavf_enable_vlan_stripping
  * @adapter: adapter structure
  *
@@ -2142,6 +2170,19 @@ void iavf_virtchnl_completion(struct iavf_adapter *adapter,
 			dev_warn(&adapter->pdev->dev, "Failed to add VLAN filter, error %s\n",
 				 iavf_stat_str(&adapter->hw, v_retval));
 			break;
+		case VIRTCHNL_OP_CONFIG_RSS_HFUNC:
+			dev_warn(&adapter->pdev->dev, "Failed to configure hash function, error %s\n",
+				 iavf_stat_str(&adapter->hw, v_retval));
+
+			if (adapter->hfunc ==
+					VIRTCHNL_RSS_ALG_TOEPLITZ_SYMMETRIC)
+				adapter->hfunc =
+					VIRTCHNL_RSS_ALG_TOEPLITZ_ASYMMETRIC;
+			else
+				adapter->hfunc =
+					VIRTCHNL_RSS_ALG_TOEPLITZ_SYMMETRIC;
+
+			break;
 		default:
 			dev_err(&adapter->pdev->dev, "PF returned error %d (%s) to our request %d\n",
 				v_retval, iavf_stat_str(&adapter->hw, v_retval),