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, 93 insertions, 0 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls.c b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls.c
new file mode 100644
index 000000000000..d2ff74d52720
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+// Copyright (c) 2019 Mellanox Technologies.
+
+#include "en.h"
+#include "en_accel/ktls.h"
+
+static int mlx5e_ktls_create_tis(struct mlx5_core_dev *mdev, u32 *tisn)
+{
+	u32 in[MLX5_ST_SZ_DW(create_tis_in)] = {};
+	void *tisc;
+
+	tisc = MLX5_ADDR_OF(create_tis_in, in, ctx);
+
+	MLX5_SET(tisc, tisc, tls_en, 1);
+
+	return mlx5e_create_tis(mdev, in, tisn);
+}
+
+static int mlx5e_ktls_add(struct net_device *netdev, struct sock *sk,
+			  enum tls_offload_ctx_dir direction,
+			  struct tls_crypto_info *crypto_info,
+			  u32 start_offload_tcp_sn)
+{
+	struct mlx5e_priv *priv = netdev_priv(netdev);
+	struct mlx5e_ktls_offload_context_tx *tx_priv;
+	struct tls_context *tls_ctx = tls_get_ctx(sk);
+	struct mlx5_core_dev *mdev = priv->mdev;
+	int err;
+
+	if (WARN_ON(direction != TLS_OFFLOAD_CTX_DIR_TX))
+		return -EINVAL;
+
+	if (WARN_ON(!mlx5e_ktls_type_check(mdev, crypto_info)))
+		return -EOPNOTSUPP;
+
+	tx_priv = kvzalloc(sizeof(*tx_priv), GFP_KERNEL);
+	if (!tx_priv)
+		return -ENOMEM;
+
+	tx_priv->expected_seq = start_offload_tcp_sn;
+	tx_priv->crypto_info  = crypto_info;
+	mlx5e_set_ktls_tx_priv_ctx(tls_ctx, tx_priv);
+
+	/* tc and underlay_qpn values are not in use for tls tis */
+	err = mlx5e_ktls_create_tis(mdev, &tx_priv->tisn);
+	if (err)
+		goto create_tis_fail;
+
+	err = mlx5_ktls_create_key(mdev, crypto_info, &tx_priv->key_id);
+	if (err)
+		goto encryption_key_create_fail;
+
+	mlx5e_ktls_tx_offload_set_pending(tx_priv);
+
+	return 0;
+
+encryption_key_create_fail:
+	mlx5e_destroy_tis(priv->mdev, tx_priv->tisn);
+create_tis_fail:
+	kvfree(tx_priv);
+	return err;
+}
+
+static void mlx5e_ktls_del(struct net_device *netdev,
+			   struct tls_context *tls_ctx,
+			   enum tls_offload_ctx_dir direction)
+{
+	struct mlx5e_priv *priv = netdev_priv(netdev);
+	struct mlx5e_ktls_offload_context_tx *tx_priv =
+		mlx5e_get_ktls_tx_priv_ctx(tls_ctx);
+
+	mlx5_ktls_destroy_key(priv->mdev, tx_priv->key_id);
+	mlx5e_destroy_tis(priv->mdev, tx_priv->tisn);
+	kvfree(tx_priv);
+}
+
+static const struct tlsdev_ops mlx5e_ktls_ops = {
+	.tls_dev_add = mlx5e_ktls_add,
+	.tls_dev_del = mlx5e_ktls_del,
+};
+
+void mlx5e_ktls_build_netdev(struct mlx5e_priv *priv)
+{
+	struct net_device *netdev = priv->netdev;
+
+	if (!mlx5_accel_is_ktls_device(priv->mdev))
+		return;
+
+	netdev->hw_features |= NETIF_F_HW_TLS_TX;
+	netdev->features    |= NETIF_F_HW_TLS_TX;
+
+	netdev->tlsdev_ops = &mlx5e_ktls_ops;
+}