net/mlx5: Refactor the encryption key creation

Move the common code to general functions which can be used by fast
update encryption key in later patches.
Signed-off-by: Jianbo Liu <jianbol@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

drivers/net/ethernet/mellanox/mlx5/core/lib/crypto.c

@@ -9,50 +9,79 @@ struct mlx5_crypto_dek_priv {
 	int log_dek_obj_range;
 };
 
+static int mlx5_crypto_dek_get_key_sz(struct mlx5_core_dev *mdev,
+				      u32 sz_bytes, u8 *key_sz_p)
+{
+	u32 sz_bits = sz_bytes * BITS_PER_BYTE;
+
+	switch (sz_bits) {
+	case 128:
+		*key_sz_p = MLX5_GENERAL_OBJECT_TYPE_ENCRYPTION_KEY_KEY_SIZE_128;
+		break;
+	case 256:
+		*key_sz_p = MLX5_GENERAL_OBJECT_TYPE_ENCRYPTION_KEY_KEY_SIZE_256;
+		break;
+	default:
+		mlx5_core_err(mdev, "Crypto offload error, invalid key size (%u bits)\n",
+			      sz_bits);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int mlx5_crypto_dek_fill_key(struct mlx5_core_dev *mdev, u8 *key_obj,
+				    const void *key, u32 sz_bytes)
+{
+	void *dst;
+	u8 key_sz;
+	int err;
+
+	err = mlx5_crypto_dek_get_key_sz(mdev, sz_bytes, &key_sz);
+	if (err)
+		return err;
+
+	MLX5_SET(encryption_key_obj, key_obj, key_size, key_sz);
+
+	if (sz_bytes == 16)
+		/* For key size of 128b the MSBs are reserved. */
+		dst = MLX5_ADDR_OF(encryption_key_obj, key_obj, key[1]);
+	else
+		dst = MLX5_ADDR_OF(encryption_key_obj, key_obj, key);
+
+	memcpy(dst, key, sz_bytes);
+
+	return 0;
+}
+
 int mlx5_create_encryption_key(struct mlx5_core_dev *mdev,
 			       const void *key, u32 sz_bytes,
 			       u32 key_type, u32 *p_key_id)
 {
 	u32 in[MLX5_ST_SZ_DW(create_encryption_key_in)] = {};
 	u32 out[MLX5_ST_SZ_DW(general_obj_out_cmd_hdr)];
-	u32 sz_bits = sz_bytes * BITS_PER_BYTE;
-	u8  general_obj_key_size;
 	u64 general_obj_types;
-	void *obj, *key_p;
+	void *obj;
 	int err;
 
-	obj = MLX5_ADDR_OF(create_encryption_key_in, in, encryption_key_object);
-	key_p = MLX5_ADDR_OF(encryption_key_obj, obj, key);
-
 	general_obj_types = MLX5_CAP_GEN_64(mdev, general_obj_types);
 	if (!(general_obj_types &
 	      MLX5_HCA_CAP_GENERAL_OBJECT_TYPES_ENCRYPTION_KEY))
 		return -EINVAL;
 
-	switch (sz_bits) {
-	case 128:
-		general_obj_key_size =
-			MLX5_GENERAL_OBJECT_TYPE_ENCRYPTION_KEY_KEY_SIZE_128;
-		key_p += sz_bytes;
-		break;
-	case 256:
-		general_obj_key_size =
-			MLX5_GENERAL_OBJECT_TYPE_ENCRYPTION_KEY_KEY_SIZE_256;
-		break;
-	default:
-		return -EINVAL;
-	}
-
-	memcpy(key_p, key, sz_bytes);
-
-	MLX5_SET(encryption_key_obj, obj, key_size, general_obj_key_size);
-	MLX5_SET(encryption_key_obj, obj, key_purpose, key_type);
 	MLX5_SET(general_obj_in_cmd_hdr, in, opcode,
 		 MLX5_CMD_OP_CREATE_GENERAL_OBJECT);
 	MLX5_SET(general_obj_in_cmd_hdr, in, obj_type,
 		 MLX5_GENERAL_OBJECT_TYPES_ENCRYPTION_KEY);
+
+	obj = MLX5_ADDR_OF(create_encryption_key_in, in, encryption_key_object);
+	MLX5_SET(encryption_key_obj, obj, key_purpose, key_type);
 	MLX5_SET(encryption_key_obj, obj, pd, mdev->mlx5e_res.hw_objs.pdn);
 
+	err = mlx5_crypto_dek_fill_key(mdev, obj, key, sz_bytes);
+	if (err)
+		return err;
+
 	err = mlx5_cmd_exec(mdev, in, sizeof(in), out, sizeof(out));
 	if (!err)
 		*p_key_id = MLX5_GET(general_obj_out_cmd_hdr, out, obj_id);