net/mlx5e: RX, Add checks for calculated Striding RQ attributes

Striding RQ attributes below are mutually dependent. An unaware
change to one might take the others out of the valid range derived
by the HW caps:
- The MPWQE size in bytes
- The number of strides in a MPWQE
- The stride size

Add checks to verify they are valid and comply to the HW spec
and SW assumptions/requirements.
This is not a fix, no particular issue exists today.

Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

3 files changed, 71 insertions, 40 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/params.c b/drivers/net/ethernet/mellanox/mlx5/core/en/params.c
index 69f1f41b2b83..f410c1268422 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/params.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/params.c
@@ -90,30 +90,39 @@ bool mlx5e_rx_is_linear_skb(struct mlx5e_params *params,
 	return !params->lro_en && linear_frag_sz <= PAGE_SIZE;
 }
 
-#define MLX5_MAX_MPWQE_LOG_WQE_STRIDE_SZ ((BIT(__mlx5_bit_sz(wq, log_wqe_stride_size)) - 1) + \
-					  MLX5_MPWQE_LOG_STRIDE_SZ_BASE)
-bool mlx5e_rx_mpwqe_is_linear_skb(struct mlx5_core_dev *mdev,
-				  struct mlx5e_params *params,
-				  struct mlx5e_xsk_param *xsk)
+bool mlx5e_verify_rx_mpwqe_strides(struct mlx5_core_dev *mdev,
+				   u8 log_stride_sz, u8 log_num_strides)
 {
-	u32 linear_frag_sz = mlx5e_rx_get_linear_frag_sz(params, xsk);
-	s8 signed_log_num_strides_param;
-	u8 log_num_strides;
+	if (log_stride_sz + log_num_strides != MLX5_MPWRQ_LOG_WQE_SZ)
+		return false;
 
-	if (!mlx5e_rx_is_linear_skb(params, xsk))
+	if (log_stride_sz < MLX5_MPWQE_LOG_STRIDE_SZ_BASE ||
+	    log_stride_sz > MLX5_MPWQE_LOG_STRIDE_SZ_MAX)
 		return false;
 
-	if (order_base_2(linear_frag_sz) > MLX5_MAX_MPWQE_LOG_WQE_STRIDE_SZ)
+	if (log_num_strides > MLX5_MPWQE_LOG_NUM_STRIDES_MAX)
 		return false;
 
 	if (MLX5_CAP_GEN(mdev, ext_stride_num_range))
-		return true;
+		return log_num_strides >= MLX5_MPWQE_LOG_NUM_STRIDES_EXT_BASE;
 
-	log_num_strides = MLX5_MPWRQ_LOG_WQE_SZ - order_base_2(linear_frag_sz);
-	signed_log_num_strides_param =
-		(s8)log_num_strides - MLX5_MPWQE_LOG_NUM_STRIDES_BASE;
+	return log_num_strides >= MLX5_MPWQE_LOG_NUM_STRIDES_BASE;
+}
 
-	return signed_log_num_strides_param >= 0;
+bool mlx5e_rx_mpwqe_is_linear_skb(struct mlx5_core_dev *mdev,
+				  struct mlx5e_params *params,
+				  struct mlx5e_xsk_param *xsk)
+{
+	s8 log_num_strides;
+	u8 log_stride_sz;
+
+	if (!mlx5e_rx_is_linear_skb(params, xsk))
+		return false;
+
+	log_stride_sz = order_base_2(mlx5e_rx_get_linear_frag_sz(params, xsk));
+	log_num_strides = MLX5_MPWRQ_LOG_WQE_SZ - log_stride_sz;
+
+	return mlx5e_verify_rx_mpwqe_strides(mdev, log_stride_sz, log_num_strides);
 }
 
 u8 mlx5e_mpwqe_get_log_rq_size(struct mlx5e_params *params,
@@ -462,26 +471,36 @@ static void mlx5e_build_rx_cq_param(struct mlx5_core_dev *mdev,
 	param->cq_period_mode = params->rx_cq_moderation.cq_period_mode;
 }
 
-void mlx5e_build_rq_param(struct mlx5_core_dev *mdev,
-			  struct mlx5e_params *params,
-			  struct mlx5e_xsk_param *xsk,
-			  u16 q_counter,
-			  struct mlx5e_rq_param *param)
+int mlx5e_build_rq_param(struct mlx5_core_dev *mdev,
+			 struct mlx5e_params *params,
+			 struct mlx5e_xsk_param *xsk,
+			 u16 q_counter,
+			 struct mlx5e_rq_param *param)
 {
 	void *rqc = param->rqc;
 	void *wq = MLX5_ADDR_OF(rqc, rqc, wq);
 	int ndsegs = 1;
 
 	switch (params->rq_wq_type) {
-	case MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ:
+	case MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ: {
+		u8 log_wqe_num_of_strides = mlx5e_mpwqe_get_log_num_strides(mdev, params, xsk);
+		u8 log_wqe_stride_size = mlx5e_mpwqe_get_log_stride_size(mdev, params, xsk);
+
+		if (!mlx5e_verify_rx_mpwqe_strides(mdev, log_wqe_stride_size,
+						   log_wqe_num_of_strides)) {
+			mlx5_core_err(mdev,
+				      "Bad RX MPWQE params: log_stride_size %u, log_num_strides %u\n",
+				      log_wqe_stride_size, log_wqe_num_of_strides);
+			return -EINVAL;
+		}
+
 		MLX5_SET(wq, wq, log_wqe_num_of_strides,
-			 mlx5e_mpwqe_get_log_num_strides(mdev, params, xsk) -
-			 MLX5_MPWQE_LOG_NUM_STRIDES_BASE);
+			 log_wqe_num_of_strides - MLX5_MPWQE_LOG_NUM_STRIDES_BASE);
 		MLX5_SET(wq, wq, log_wqe_stride_size,
-			 mlx5e_mpwqe_get_log_stride_size(mdev, params, xsk) -
-			 MLX5_MPWQE_LOG_STRIDE_SZ_BASE);
+			 log_wqe_stride_size - MLX5_MPWQE_LOG_STRIDE_SZ_BASE);
 		MLX5_SET(wq, wq, log_wq_sz, mlx5e_mpwqe_get_log_rq_size(params, xsk));
 		break;
+	}
 	default: /* MLX5_WQ_TYPE_CYCLIC */
 		MLX5_SET(wq, wq, log_wq_sz, params->log_rq_mtu_frames);
 		mlx5e_build_rq_frags_info(mdev, params, xsk, &param->frags_info);
@@ -499,6 +518,8 @@ void mlx5e_build_rq_param(struct mlx5_core_dev *mdev,
 
 	param->wq.buf_numa_node = dev_to_node(mlx5_core_dma_dev(mdev));
 	mlx5e_build_rx_cq_param(mdev, params, xsk, &param->cqp);
+
+	return 0;
 }
 
 void mlx5e_build_drop_rq_param(struct mlx5_core_dev *mdev,
@@ -643,14 +664,17 @@ void mlx5e_build_xdpsq_param(struct mlx5_core_dev *mdev,
 	mlx5e_build_tx_cq_param(mdev, params, &param->cqp);
 }
 
-void mlx5e_build_channel_param(struct mlx5_core_dev *mdev,
-			       struct mlx5e_params *params,
-			       u16 q_counter,
-			       struct mlx5e_channel_param *cparam)
+int mlx5e_build_channel_param(struct mlx5_core_dev *mdev,
+			      struct mlx5e_params *params,
+			      u16 q_counter,
+			      struct mlx5e_channel_param *cparam)
 {
 	u8 icosq_log_wq_sz, async_icosq_log_wq_sz;
+	int err;
 
-	mlx5e_build_rq_param(mdev, params, NULL, q_counter, &cparam->rq);
+	err = mlx5e_build_rq_param(mdev, params, NULL, q_counter, &cparam->rq);
+	if (err)
+		return err;
 
 	icosq_log_wq_sz = mlx5e_build_icosq_log_wq_sz(params, &cparam->rq);
 	async_icosq_log_wq_sz = mlx5e_build_async_icosq_log_wq_sz(mdev);
@@ -659,4 +683,6 @@ void mlx5e_build_channel_param(struct mlx5_core_dev *mdev,
 	mlx5e_build_xdpsq_param(mdev, params, &cparam->xdp_sq);
 	mlx5e_build_icosq_param(mdev, icosq_log_wq_sz, &cparam->icosq);
 	mlx5e_build_async_icosq_param(mdev, async_icosq_log_wq_sz, &cparam->async_icosq);
+
+	return 0;
 }
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/params.h b/drivers/net/ethernet/mellanox/mlx5/core/en/params.h
index fcc51ec6084e..e9593f5f0661 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/params.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/params.h
@@ -96,6 +96,8 @@ void mlx5e_build_rq_params(struct mlx5_core_dev *mdev, struct mlx5e_params *para
 void mlx5e_set_rq_type(struct mlx5_core_dev *mdev, struct mlx5e_params *params);
 void mlx5e_init_rq_type_params(struct mlx5_core_dev *mdev, struct mlx5e_params *params);
 
+bool mlx5e_verify_rx_mpwqe_strides(struct mlx5_core_dev *mdev,
+				   u8 log_stride_sz, u8 log_num_strides);
 u16 mlx5e_get_linear_rq_headroom(struct mlx5e_params *params,
 				 struct mlx5e_xsk_param *xsk);
 u32 mlx5e_rx_get_min_frag_sz(struct mlx5e_params *params,
@@ -122,11 +124,11 @@ u16 mlx5e_get_rq_headroom(struct mlx5_core_dev *mdev,
 /* Build queue parameters */
 
 void mlx5e_build_create_cq_param(struct mlx5e_create_cq_param *ccp, struct mlx5e_channel *c);
-void mlx5e_build_rq_param(struct mlx5_core_dev *mdev,
-			  struct mlx5e_params *params,
-			  struct mlx5e_xsk_param *xsk,
-			  u16 q_counter,
-			  struct mlx5e_rq_param *param);
+int mlx5e_build_rq_param(struct mlx5_core_dev *mdev,
+			 struct mlx5e_params *params,
+			 struct mlx5e_xsk_param *xsk,
+			 u16 q_counter,
+			 struct mlx5e_rq_param *param);
 void mlx5e_build_drop_rq_param(struct mlx5_core_dev *mdev,
 			       u16 q_counter,
 			       struct mlx5e_rq_param *param);
@@ -141,10 +143,10 @@ void mlx5e_build_tx_cq_param(struct mlx5_core_dev *mdev,
 void mlx5e_build_xdpsq_param(struct mlx5_core_dev *mdev,
 			     struct mlx5e_params *params,
 			     struct mlx5e_sq_param *param);
-void mlx5e_build_channel_param(struct mlx5_core_dev *mdev,
-			       struct mlx5e_params *params,
-			       u16 q_counter,
-			       struct mlx5e_channel_param *cparam);
+int mlx5e_build_channel_param(struct mlx5_core_dev *mdev,
+			      struct mlx5e_params *params,
+			      u16 q_counter,
+			      struct mlx5e_channel_param *cparam);
 
 u16 mlx5e_calc_sq_stop_room(struct mlx5_core_dev *mdev, struct mlx5e_params *params);
 int mlx5e_validate_params(struct mlx5_core_dev *mdev, struct mlx5e_params *params);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index bc2d37d2806f..bca832cdc4cb 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -2086,7 +2086,10 @@ int mlx5e_open_channels(struct mlx5e_priv *priv,
 	if (!chs->c || !cparam)
 		goto err_free;
 
-	mlx5e_build_channel_param(priv->mdev, &chs->params, priv->q_counter, cparam);
+	err = mlx5e_build_channel_param(priv->mdev, &chs->params, priv->q_counter, cparam);
+	if (err)
+		goto err_free;
+
 	for (i = 0; i < chs->num; i++) {
 		struct xsk_buff_pool *xsk_pool = NULL;