net/mlx5: Fix flowhash key set/get for custom RSS

mlx5 flow hash field retrieval and set only worked on the default
RSS context as of commit f01cc58 ("net/mlx5e: Support multiple RSS
contexts"), not custom RSS contexts.

For example, before this patch attempting to retrieve the flow hash fields
for RSS context 1 fails:

$ sudo ethtool -u eth1 rx-flow-hash tcp4 context 1
Cannot get RX network flow hashing options: Invalid argument

This patch fixes getting and setting the flow hash fields for contexts
other than the default context.

Getting the flow hash fields for RSS context 1:

$ sudo ethtool -u eth1 rx-flow-hash tcp4 context 1
For RSS context 1:
TCP over IPV4 flows use these fields for computing Hash flow key:
IP DA

Now, setting the flash hash fields to a custom value:

$ sudo ethtool -U eth1 rx-flow-hash tcp4 sdfn context 1

And retrieving them again:

$ sudo ethtool -u eth1 rx-flow-hash tcp4 context 1
For RSS context 1:
TCP over IPV4 flows use these fields for computing Hash flow key:
IP SA
IP DA
L4 bytes 0 & 1 [TCP/UDP src port]
L4 bytes 2 & 3 [TCP/UDP dst port]

Signed-off-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: jdamato-fsly

drivers/net/ethernet/mellanox/mlx5/core/en/rx_res.c

@@ -218,17 +218,32 @@ int mlx5e_rx_res_rss_set_rxfh(struct mlx5e_rx_res *res, u32 rss_idx,
 	return mlx5e_rss_set_rxfh(rss, indir, key, hfunc, res->rss_rqns, res->rss_nch);
 }
 
-u8 mlx5e_rx_res_rss_get_hash_fields(struct mlx5e_rx_res *res, enum mlx5_traffic_types tt)
+int mlx5e_rx_res_rss_get_hash_fields(struct mlx5e_rx_res *res, u32 rss_idx,
+				     enum mlx5_traffic_types tt)
 {
-	struct mlx5e_rss *rss = res->rss[0];
+	struct mlx5e_rss *rss;
+
+	if (rss_idx >= MLX5E_MAX_NUM_RSS)
+		return -EINVAL;
+
+	rss = res->rss[rss_idx];
+	if (!rss)
+		return -ENOENT;
 
 	return mlx5e_rss_get_hash_fields(rss, tt);
 }
 
-int mlx5e_rx_res_rss_set_hash_fields(struct mlx5e_rx_res *res, enum mlx5_traffic_types tt,
-				     u8 rx_hash_fields)
+int mlx5e_rx_res_rss_set_hash_fields(struct mlx5e_rx_res *res, u32 rss_idx,
+				     enum mlx5_traffic_types tt, u8 rx_hash_fields)
 {
-	struct mlx5e_rss *rss = res->rss[0];
+	struct mlx5e_rss *rss;
+
+	if (rss_idx >= MLX5E_MAX_NUM_RSS)
+		return -EINVAL;
+
+	rss = res->rss[rss_idx];
+	if (!rss)
+		return -ENOENT;
 
 	return mlx5e_rss_set_hash_fields(rss, tt, rx_hash_fields);
 }

drivers/net/ethernet/mellanox/mlx5/core/en/rx_res.h

@@ -48,9 +48,10 @@ int mlx5e_rx_res_rss_get_rxfh(struct mlx5e_rx_res *res, u32 rss_idx,
 int mlx5e_rx_res_rss_set_rxfh(struct mlx5e_rx_res *res, u32 rss_idx,
 			      const u32 *indir, const u8 *key, const u8 *hfunc);
 
-u8 mlx5e_rx_res_rss_get_hash_fields(struct mlx5e_rx_res *res, enum mlx5_traffic_types tt);
-int mlx5e_rx_res_rss_set_hash_fields(struct mlx5e_rx_res *res, enum mlx5_traffic_types tt,
-				     u8 rx_hash_fields);
+int mlx5e_rx_res_rss_get_hash_fields(struct mlx5e_rx_res *res, u32 rss_idx,
+				     enum mlx5_traffic_types tt);
+int mlx5e_rx_res_rss_set_hash_fields(struct mlx5e_rx_res *res, u32 rss_idx,
+				     enum mlx5_traffic_types tt, u8 rx_hash_fields);
 int mlx5e_rx_res_packet_merge_set_param(struct mlx5e_rx_res *res,
 					struct mlx5e_packet_merge_param *pkt_merge_param);
 

drivers/net/ethernet/mellanox/mlx5/core/en_fs_ethtool.c

@@ -900,21 +900,27 @@ static int mlx5e_set_rss_hash_opt(struct mlx5e_priv *priv,
 				  struct ethtool_rxnfc *nfc)
 {
 	u8 rx_hash_field = 0;
+	u32 flow_type = 0;
+	u32 rss_idx = 0;
 	int err;
 	int tt;
 
-	tt = flow_type_to_traffic_type(nfc->flow_type);
+	if (nfc->flow_type & FLOW_RSS)
+		rss_idx = nfc->rss_context;
+
+	flow_type = flow_type_mask(nfc->flow_type);
+	tt = flow_type_to_traffic_type(flow_type);
 	if (tt < 0)
 		return tt;
 
 	/*  RSS does not support anything other than hashing to queues
 	 *  on src IP, dest IP, TCP/UDP src port and TCP/UDP dest
 	 *  port.
 	 */
-	if (nfc->flow_type != TCP_V4_FLOW &&
-	    nfc->flow_type != TCP_V6_FLOW &&
-	    nfc->flow_type != UDP_V4_FLOW &&
-	    nfc->flow_type != UDP_V6_FLOW)
+	if (flow_type != TCP_V4_FLOW &&
+	    flow_type != TCP_V6_FLOW &&
+	    flow_type != UDP_V4_FLOW &&
+	    flow_type != UDP_V6_FLOW)
 		return -EOPNOTSUPP;
 
 	if (nfc->data & ~(RXH_IP_SRC | RXH_IP_DST |
@@ -931,7 +937,7 @@ static int mlx5e_set_rss_hash_opt(struct mlx5e_priv *priv,
 		rx_hash_field |= MLX5_HASH_FIELD_SEL_L4_DPORT;
 
 	mutex_lock(&priv->state_lock);
-	err = mlx5e_rx_res_rss_set_hash_fields(priv->rx_res, tt, rx_hash_field);
+	err = mlx5e_rx_res_rss_set_hash_fields(priv->rx_res, rss_idx, tt, rx_hash_field);
 	mutex_unlock(&priv->state_lock);
 
 	return err;
@@ -940,14 +946,23 @@ static int mlx5e_set_rss_hash_opt(struct mlx5e_priv *priv,
 static int mlx5e_get_rss_hash_opt(struct mlx5e_priv *priv,
 				  struct ethtool_rxnfc *nfc)
 {
-	u32 hash_field = 0;
+	int hash_field = 0;
+	u32 flow_type = 0;
+	u32 rss_idx = 0;
 	int tt;
 
-	tt = flow_type_to_traffic_type(nfc->flow_type);
+	if (nfc->flow_type & FLOW_RSS)
+		rss_idx = nfc->rss_context;
+
+	flow_type = flow_type_mask(nfc->flow_type);
+	tt = flow_type_to_traffic_type(flow_type);
 	if (tt < 0)
 		return tt;
 
-	hash_field = mlx5e_rx_res_rss_get_hash_fields(priv->rx_res, tt);
+	hash_field = mlx5e_rx_res_rss_get_hash_fields(priv->rx_res, rss_idx, tt);
+	if (hash_field < 0)
+		return hash_field;
+
 	nfc->data = 0;
 
 	if (hash_field & MLX5_HASH_FIELD_SEL_SRC_IP)