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In-Reply-To: <20221204100653.19019-1-ehakim@nvidia.com>
References: <20221204100653.19019-1-ehakim@nvidia.com>
Subject: Re: [PATCH net-next] macsec: Add support for IFLA_MACSEC_OFFLOAD in the netlink layer
From:   Antoine Tenart <atenart@kernel.org>
Cc:     raeds@nvidia.com, davem@davemloft.net, edumazet@google.com,
        kuba@kernel.org, pabeni@redhat.com, netdev@vger.kernel.org,
        sd@queasysnail.net, Emeel Hakim <ehakim@nvidia.com>
To:     ehakim@nvidia.com, linux-kernel@vger.kernel.org
Date:   Mon, 05 Dec 2022 10:54:30 +0100
Message-ID: <167023407010.4545.3574025885845288724@kwain.local>
Precedence: bulk

Hello,

Quoting ehakim@nvidia.com (2022-12-04 11:06:53)
> =20
> +static int macsec_changelink_upd_offload(struct net_device *dev, struct =
nlattr *data[])
> +{
> +       enum macsec_offload offload, prev_offload;
> +       const struct macsec_ops *ops;
> +       struct macsec_context ctx;
> +       struct macsec_dev *macsec;
> +       int ret =3D 0;
> +
> +       macsec =3D macsec_priv(dev);
> +       offload =3D nla_get_u8(data[IFLA_MACSEC_OFFLOAD]);
> +
> +       /* Check if the offloading mode is supported by the underlying la=
yers */
> +       if (offload !=3D MACSEC_OFFLOAD_OFF &&
> +           !macsec_check_offload(offload, macsec))
> +               return -EOPNOTSUPP;
> +
> +       /* Check if the net device is busy. */
> +       if (netif_running(dev))
> +               return -EBUSY;
> +
> +       if (macsec->offload =3D=3D offload)
> +               return 0;
> +
> +       prev_offload =3D macsec->offload;
> +
> +       /* Check if the device already has rules configured: we do not su=
pport
> +        * rules migration.
> +        */
> +       if (macsec_is_configured(macsec))
> +               return -EBUSY;
> +
> +       ops =3D __macsec_get_ops(offload =3D=3D MACSEC_OFFLOAD_OFF ? prev=
_offload : offload,
> +                              macsec, &ctx);
> +       if (!ops)
> +               return -EOPNOTSUPP;
> +
> +       macsec->offload =3D offload;
> +
> +       ctx.secy =3D &macsec->secy;
> +       ret =3D (offload =3D=3D MACSEC_OFFLOAD_OFF) ? macsec_offload(ops-=
>mdo_del_secy, &ctx) :
> +                     macsec_offload(ops->mdo_add_secy, &ctx);
> +
> +       if (ret)
> +               macsec->offload =3D prev_offload;
> +
> +       return ret;
> +}

The logic above is very close to what is done in macsec_upd_offload,
except for the use of the rtnl lock. You can merge the two in a common
helper and use that to avoid duplication.

Thanks,
Antoine