Subject: Re: [iwl-next v5 07/15] ice: implement netdev for subfunction

From: Maciej Fijalkowski <[email-masked]>
Date: Thu, 27 Jun 2024 13:13:47 +0200

On Thu, Jun 06, 2024 at 01:24:55PM +0200, Michal Swiatkowski wrote:
> From: Piotr Raczynski <[email-masked]>
> 
> Configure netdevice for subfunction usecase. Mostly it is reusing ops
> from the PF netdevice.
> 
> SF netdev is linked to devlink port registered after SF activation.
> 
> Reviewed-by: Simon Horman <[email-masked]>
> Reviewed-by: Jiri Pirko <[email-masked]>
> Signed-off-by: Piotr Raczynski <[email-masked]>
> Signed-off-by: Michal Swiatkowski <[email-masked]>
> ---
>  drivers/net/ethernet/intel/ice/ice_sf_eth.c | 85 ++++++++++++++++++++-
>  1 file changed, 84 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/intel/ice/ice_sf_eth.c b/drivers/net/ethernet/intel/ice/ice_sf_eth.c
> index abe495c2d033..3a540a2638d1 100644
> --- a/drivers/net/ethernet/intel/ice/ice_sf_eth.c
> +++ b/drivers/net/ethernet/intel/ice/ice_sf_eth.c
> @@ -2,11 +2,85 @@
>  /* Copyright (c) 2024, Intel Corporation. */
>  #include "ice.h"
>  #include "ice_lib.h"
> +#include "ice_txrx.h"
>  #include "ice_fltr.h"
>  #include "ice_sf_eth.h"
>  #include "devlink/devlink_port.h"
>  #include "devlink/devlink.h"
>  
> +static const struct net_device_ops ice_sf_netdev_ops = {
> +	.ndo_open = ice_open,
> +	.ndo_stop = ice_stop,
> +	.ndo_start_xmit = ice_start_xmit,
> +	.ndo_vlan_rx_add_vid = ice_vlan_rx_add_vid,
> +	.ndo_vlan_rx_kill_vid = ice_vlan_rx_kill_vid,
> +	.ndo_change_mtu = ice_change_mtu,
> +	.ndo_get_stats64 = ice_get_stats64,
> +	.ndo_tx_timeout = ice_tx_timeout,
> +	.ndo_bpf = ice_xdp,
> +	.ndo_xdp_xmit = ice_xdp_xmit,
> +	.ndo_xsk_wakeup = ice_xsk_wakeup,
> +};
> +
> +/**
> + * ice_sf_cfg_netdev - Allocate, configure and register a netdev
> + * @dyn_port: subfunction associated with configured netdev
> + * @devlink_port: subfunction devlink port to be linked with netdev
> + *
> + * Return: 0 on success, negative value on failure
> + */
> +static int ice_sf_cfg_netdev(struct ice_dynamic_port *dyn_port,
> +			     struct devlink_port *devlink_port)
> +{
> +	struct ice_vsi *vsi = dyn_port->vsi;
> +	struct ice_netdev_priv *np;
> +	struct net_device *netdev;
> +	int err;
> +
> +	netdev = alloc_etherdev_mqs(sizeof(*np), vsi->alloc_txq,
> +				    vsi->alloc_rxq);
> +	if (!netdev)
> +		return -ENOMEM;
> +
> +	SET_NETDEV_DEV(netdev, &vsi->back->pdev->dev);
> +	set_bit(ICE_VSI_NETDEV_ALLOCD, vsi->state);
> +	vsi->netdev = netdev;
> +	np = netdev_priv(netdev);
> +	np->vsi = vsi;
> +
> +	ice_set_netdev_features(netdev);
> +
> +	netdev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT |
> +			       NETDEV_XDP_ACT_XSK_ZEROCOPY |
> +			       NETDEV_XDP_ACT_RX_SG;

please include:

	netdev->xdp_zc_max_segs = ICE_MAX_BUF_TXD;

so that xsk ZC multi-buffer is also supported on SF netdevs.

> +
> +	eth_hw_addr_set(netdev, dyn_port->hw_addr);
> +	ether_addr_copy(netdev->perm_addr, dyn_port->hw_addr);
> +	netdev->netdev_ops = &ice_sf_netdev_ops;
> +	SET_NETDEV_DEVLINK_PORT(netdev, devlink_port);
> +
> +	err = register_netdev(netdev);
> +	if (err) {
> +		free_netdev(netdev);
> +		vsi->netdev = NULL;
> +		return -ENOMEM;
> +	}
> +	set_bit(ICE_VSI_NETDEV_REGISTERED, vsi->state);
> +	netif_carrier_off(netdev);
> +	netif_tx_stop_all_queues(netdev);
> +
> +	return 0;
> +}
> +
> +static void ice_sf_decfg_netdev(struct ice_vsi *vsi)
> +{
> +	unregister_netdev(vsi->netdev);
> +	clear_bit(ICE_VSI_NETDEV_REGISTERED, vsi->state);
> +	free_netdev(vsi->netdev);
> +	vsi->netdev = NULL;
> +	clear_bit(ICE_VSI_NETDEV_ALLOCD, vsi->state);
> +}
> +
>  /**
>   * ice_sf_dev_probe - subfunction driver probe function
>   * @adev: pointer to the auxiliary device
> @@ -57,10 +131,16 @@ static int ice_sf_dev_probe(struct auxiliary_device *adev,
>  		goto err_vsi_decfg;
>  	}
>  
> +	err = ice_sf_cfg_netdev(dyn_port, &sf_dev->priv->devlink_port);
> +	if (err) {
> +		dev_err(dev, "Subfunction netdev config failed");
> +		goto err_devlink_destroy;
> +	}
> +
>  	err = devl_port_fn_devlink_set(&dyn_port->devlink_port, devlink);
>  	if (err) {
>  		dev_err(dev, "Can't link devlink instance to SF devlink port");
> -		goto err_devlink_destroy;
> +		goto err_netdev_decfg;
>  	}
>  
>  	ice_napi_add(vsi);
> @@ -70,6 +150,8 @@ static int ice_sf_dev_probe(struct auxiliary_device *adev,
>  
>  	return 0;
>  
> +err_netdev_decfg:
> +	ice_sf_decfg_netdev(vsi);
>  err_devlink_destroy:
>  	ice_devlink_destroy_sf_dev_port(sf_dev);
>  err_vsi_decfg:
> @@ -98,6 +180,7 @@ static void ice_sf_dev_remove(struct auxiliary_device *adev)
>  
>  	ice_vsi_close(vsi);
>  
> +	ice_sf_decfg_netdev(vsi);
>  	ice_devlink_destroy_sf_dev_port(sf_dev);
>  	devl_unregister(devlink);
>  	devl_unlock(devlink);
> -- 
> 2.42.0
>