Subject: Re: [PATCH net-next 2/4] net/mlx5: Implement devlink port function cmds to control ipsec_crypto

From: Leon Romanovsky <[email-masked]>
Date: Wed, 29 Mar 2023 11:01:47 +0300

On Thu, Mar 23, 2023 at 01:10:57PM +0200, Dima Chumak wrote:
> Implement devlink port function commands to enable / disable IPsec
> crypto offloads.  This is used to control the IPsec capability of the
> device.
> 
> When ipsec_crypto is enabled for a VF, it prevents adding IPsec crypto
> offloads on the PF, because the two cannot be active simultaneously due
> to HW constraints. Conversely, if there are any active IPsec crypto
> offloads on the PF, it's not allowed to enable ipsec_crypto on a VF,
> until PF IPsec offloads are cleared.
> 
> Signed-off-by: Dima Chumak <[email-masked]>
> Reviewed-by: Jiri Pirko <[email-masked]>
> ---
>  .../ethernet/mellanox/mlx5/switchdev.rst      |   8 +
>  .../net/ethernet/mellanox/mlx5/core/Makefile  |   2 +-
>  .../net/ethernet/mellanox/mlx5/core/devlink.c |   2 +
>  .../mellanox/mlx5/core/en_accel/ipsec.c       |  18 ++
>  .../ethernet/mellanox/mlx5/core/esw/ipsec.c   | 271 ++++++++++++++++++
>  .../net/ethernet/mellanox/mlx5/core/eswitch.c |  29 ++
>  .../net/ethernet/mellanox/mlx5/core/eswitch.h |  20 ++
>  .../mellanox/mlx5/core/eswitch_offloads.c     | 100 +++++++
>  .../ethernet/mellanox/mlx5/core/lib/ipsec.h   |  41 +++
>  include/linux/mlx5/driver.h                   |   1 +
>  include/linux/mlx5/mlx5_ifc.h                 |   3 +
>  11 files changed, 494 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/net/ethernet/mellanox/mlx5/core/esw/ipsec.c
>  create mode 100644 drivers/net/ethernet/mellanox/mlx5/core/lib/ipsec.h

<...>

> +static int esw_ipsec_vf_query(struct mlx5_core_dev *dev, struct mlx5_vport *vport, bool *crypto)
> +{
> +	int query_sz = MLX5_ST_SZ_BYTES(query_hca_cap_out);
> +	void *hca_cap = NULL, *query_cap = NULL;
> +	bool ipsec_enabled;
> +	int err;
> +
> +	/* Querying IPsec caps only makes sense when generic ipsec_offload
> +	 * HCA cap is enabled
> +	 */
> +	err = esw_ipsec_vf_query_generic(dev, vport->index, &ipsec_enabled);
> +	if (err)
> +		return err;
> +	if (!ipsec_enabled) {
> +		*crypto = false;
> +		return 0;
> +	}
> +
> +	query_cap = kvzalloc(query_sz, GFP_KERNEL);
> +	if (!query_cap)
> +		return -ENOMEM;
> +
> +	err = mlx5_vport_get_other_func_cap(dev, vport->index, query_cap, MLX5_CAP_IPSEC);
> +	if (err)
> +		goto out;
> +
> +	hca_cap = MLX5_ADDR_OF(query_hca_cap_out, query_cap, capability);
> +	*crypto = MLX5_GET(ipsec_cap, hca_cap, ipsec_crypto_offload);

This is very optimistic check to decide if crypto is supported/enabled or not.

Take a look on mlx5_ipsec_device_caps(struct mlx5_core_dev *mdev)
implementation to take into account other capabilities too:
https://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma.git/tree/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_offload.c?h=wip/leon-for-next#n13

It will be nice if you can reuse existing MLX5_IPSEC_CAP_* enum andextend existing
mlx5_ipsec_device_caps() to query other vports.

Thanks