[PATCH net-next 2/5] net/mlx5e: advertise max RSS indirection table size to ethtool

[Tariq Toukan <tariqt@nvidia.com>]

From: Yael Chemla <ychemla@nvidia.com>

Set rxfh_indir_space to the maximum indirection table size the driver
can support: the next power of two above MLX5E_MAX_NUM_CHANNELS times
MLX5E_UNIFORM_SPREAD_RQT_FACTOR.

Without this, ethtool_rxfh_ctxs_can_resize() returns -EINVAL, blocking
non-default RSS contexts from tracking indirection table size changes
when the channel count changes.

Signed-off-by: Yael Chemla <ychemla@nvidia.com>
Reviewed-by: Nimrod Oren <noren@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/en/rqt.c     | 2 --
 drivers/net/ethernet/mellanox/mlx5/core/en/rqt.h     | 1 +
 drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c | 5 +++++
 3 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/rqt.c b/drivers/net/ethernet/mellanox/mlx5/core/en/rqt.c
index bcafb4bf9415..a3382f6a6b74 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/rqt.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/rqt.c
@@ -168,8 +168,6 @@ int mlx5e_rqt_init_indir(struct mlx5e_rqt *rqt, struct mlx5_core_dev *mdev,
 	return err;
 }
 
-#define MLX5E_UNIFORM_SPREAD_RQT_FACTOR 2
-
 u32 mlx5e_rqt_size(struct mlx5_core_dev *mdev, unsigned int num_channels)
 {
 	u32 rqt_size = max_t(u32, MLX5E_INDIR_MIN_RQT_SIZE,
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/rqt.h b/drivers/net/ethernet/mellanox/mlx5/core/en/rqt.h
index e0bc30308c77..680700e7437f 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/rqt.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/rqt.h
@@ -7,6 +7,7 @@
 #include <linux/kernel.h>
 
 #define MLX5E_INDIR_MIN_RQT_SIZE (BIT(8))
+#define MLX5E_UNIFORM_SPREAD_RQT_FACTOR 2
 
 struct mlx5_core_dev;
 
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
index a6da0219723c..c483008e33e9 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
@@ -45,6 +45,10 @@
 
 #define LANES_UNKNOWN		 0
 
+#define MLX5E_MAX_INDIR_RQT_SIZE \
+	roundup_pow_of_two(MLX5E_MAX_NUM_CHANNELS * \
+			   MLX5E_UNIFORM_SPREAD_RQT_FACTOR)
+
 void mlx5e_ethtool_get_drvinfo(struct mlx5e_priv *priv,
 			       struct ethtool_drvinfo *drvinfo)
 {
@@ -2692,6 +2696,7 @@ const struct ethtool_ops mlx5e_ethtool_ops = {
 	.supported_input_xfrm = RXH_XFRM_SYM_OR_XOR,
 	.supported_ring_params = ETHTOOL_RING_USE_TCP_DATA_SPLIT |
 				 ETHTOOL_RING_USE_HDS_THRS,
+	.rxfh_indir_space = MLX5E_MAX_INDIR_RQT_SIZE,
 	.get_drvinfo       = mlx5e_get_drvinfo,
 	.get_link          = ethtool_op_get_link,
 	.get_link_ext_state  = mlx5e_get_link_ext_state,
-- 
2.44.0