net/mlx5e: Add kTLS TX HW offload support

Add support for transmit side kernel-TLS acceleration.
Offload the crypto encryption to HW.

Per TLS connection:
- Use a separate TIS to maintain the HW context.
- Use a separate encryption key.
- Maintain static and progress HW contexts by posting the proper
  WQEs at creation time, or upon resync.
- Use a special DUMP opcode to replay the previous frags and sync
  the HW context.

To make sure the SQ is able to serve an xmit request, increase
SQ stop room to cover:
- static params WQE,
- progress params WQE, and
- resync DUMP per frag.

Currently supporting TLS 1.2, and key size 128bit.

Tested over SimX simulator.

Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 97 insertions, 0 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls.h b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls.h
new file mode 100644
index 000000000000..407da83474ef
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls.h
@@ -0,0 +1,97 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/* Copyright (c) 2019 Mellanox Technologies. */
+
+#ifndef __MLX5E_KTLS_H__
+#define __MLX5E_KTLS_H__
+
+#include "en.h"
+
+#ifdef CONFIG_MLX5_EN_TLS
+#include <net/tls.h>
+#include "accel/tls.h"
+
+#define MLX5E_KTLS_STATIC_UMR_WQE_SZ \
+	(sizeof(struct mlx5e_umr_wqe) + MLX5_ST_SZ_BYTES(tls_static_params))
+#define MLX5E_KTLS_STATIC_WQEBBS \
+	(DIV_ROUND_UP(MLX5E_KTLS_STATIC_UMR_WQE_SZ, MLX5_SEND_WQE_BB))
+
+#define MLX5E_KTLS_PROGRESS_WQE_SZ \
+	(sizeof(struct mlx5e_tx_wqe) + MLX5_ST_SZ_BYTES(tls_progress_params))
+#define MLX5E_KTLS_PROGRESS_WQEBBS \
+	(DIV_ROUND_UP(MLX5E_KTLS_PROGRESS_WQE_SZ, MLX5_SEND_WQE_BB))
+#define MLX5E_KTLS_MAX_DUMP_WQEBBS 2
+
+enum {
+	MLX5E_TLS_PROGRESS_PARAMS_AUTH_STATE_NO_OFFLOAD     = 0,
+	MLX5E_TLS_PROGRESS_PARAMS_AUTH_STATE_OFFLOAD        = 1,
+	MLX5E_TLS_PROGRESS_PARAMS_AUTH_STATE_AUTHENTICATION = 2,
+};
+
+enum {
+	MLX5E_TLS_PROGRESS_PARAMS_RECORD_TRACKER_STATE_START     = 0,
+	MLX5E_TLS_PROGRESS_PARAMS_RECORD_TRACKER_STATE_SEARCHING = 1,
+	MLX5E_TLS_PROGRESS_PARAMS_RECORD_TRACKER_STATE_TRACKING  = 2,
+};
+
+struct mlx5e_ktls_offload_context_tx {
+	struct tls_offload_context_tx *tx_ctx;
+	struct tls_crypto_info *crypto_info;
+	u32 expected_seq;
+	u32 tisn;
+	u32 key_id;
+	bool ctx_post_pending;
+};
+
+struct mlx5e_ktls_offload_context_tx_shadow {
+	struct tls_offload_context_tx         tx_ctx;
+	struct mlx5e_ktls_offload_context_tx *priv_tx;
+};
+
+static inline void
+mlx5e_set_ktls_tx_priv_ctx(struct tls_context *tls_ctx,
+			   struct mlx5e_ktls_offload_context_tx *priv_tx)
+{
+	struct tls_offload_context_tx *tx_ctx = tls_offload_ctx_tx(tls_ctx);
+	struct mlx5e_ktls_offload_context_tx_shadow *shadow;
+
+	BUILD_BUG_ON(sizeof(*shadow) > TLS_OFFLOAD_CONTEXT_SIZE_TX);
+
+	shadow = (struct mlx5e_ktls_offload_context_tx_shadow *)tx_ctx;
+
+	shadow->priv_tx = priv_tx;
+	priv_tx->tx_ctx = tx_ctx;
+}
+
+static inline struct mlx5e_ktls_offload_context_tx *
+mlx5e_get_ktls_tx_priv_ctx(struct tls_context *tls_ctx)
+{
+	struct tls_offload_context_tx *tx_ctx = tls_offload_ctx_tx(tls_ctx);
+	struct mlx5e_ktls_offload_context_tx_shadow *shadow;
+
+	BUILD_BUG_ON(sizeof(*shadow) > TLS_OFFLOAD_CONTEXT_SIZE_TX);
+
+	shadow = (struct mlx5e_ktls_offload_context_tx_shadow *)tx_ctx;
+
+	return shadow->priv_tx;
+}
+
+void mlx5e_ktls_build_netdev(struct mlx5e_priv *priv);
+void mlx5e_ktls_tx_offload_set_pending(struct mlx5e_ktls_offload_context_tx *priv_tx);
+
+struct sk_buff *mlx5e_ktls_handle_tx_skb(struct net_device *netdev,
+					 struct mlx5e_txqsq *sq,
+					 struct sk_buff *skb,
+					 struct mlx5e_tx_wqe **wqe, u16 *pi);
+void mlx5e_ktls_tx_handle_resync_dump_comp(struct mlx5e_txqsq *sq,
+					   struct mlx5e_tx_wqe_info *wi,
+					   struct mlx5e_sq_dma *dma);
+
+#else
+
+static inline void mlx5e_ktls_build_netdev(struct mlx5e_priv *priv)
+{
+}
+
+#endif
+
+#endif /* __MLX5E_TLS_H__ */