Re: [PATCH net-next v2 13/13] bnxt_en: Add support for ntuple filter deletion by ethtool.

[Simon Horman <horms@kernel.org>]

On Fri, Dec 22, 2023 at 08:22:10PM -0800, Michael Chan wrote:
> Add logic to delete a user specified ntuple filter from ethtool.
> 
> Reviewed-by: Vasundhara Volam <vasundhara-v.volam@broadcom.com>
> Reviewed-by: Andy Gospodarek <andrew.gospodarek@broadcom.com>
> Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
> Signed-off-by: Michael Chan <michael.chan@broadcom.com>
> ---
>  .../net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 29 +++++++++++++++++++
>  1 file changed, 29 insertions(+)
> 
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
> index c3b9be328b87..5629ba9f4b2e 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
> @@ -1341,6 +1341,31 @@ static int bnxt_srxclsrlins(struct bnxt *bp, struct ethtool_rxnfc *cmd)
>  	return rc;
>  }
>  
> +static int bnxt_srxclsrldel(struct bnxt *bp, struct ethtool_rxnfc *cmd)
> +{
> +	struct ethtool_rx_flow_spec *fs = &cmd->fs;
> +	struct bnxt_filter_base *fltr_base;
> +
> +	rcu_read_lock();
> +	fltr_base = bnxt_get_one_fltr_rcu(bp, bp->ntp_fltr_hash_tbl,
> +					  BNXT_NTP_FLTR_HASH_SIZE,
> +					  fs->location);
> +	if (fltr_base) {
> +		struct bnxt_ntuple_filter *fltr;
> +
> +		fltr = container_of(fltr_base, struct bnxt_ntuple_filter, base);
> +		rcu_read_unlock();
> +		if (!(fltr->base.flags & BNXT_ACT_NO_AGING))
> +			return -EINVAL;
> +		bnxt_hwrm_cfa_ntuple_filter_free(bp, fltr);
> +		bnxt_del_ntp_filter(bp, fltr);
> +		return 0;
> +	}
> +
> +	rcu_read_unlock();
> +	return -ENOENT;
> +}
> +

Hi Michael,

FWIIW, I think it would be more idoiomatic to handle
the error case inside the if condition.

(Completely untested!)

static int bnxt_srxclsrldel(struct bnxt *bp, struct ethtool_rxnfc *cmd)
{
	struct ethtool_rx_flow_spec *fs = &cmd->fs;
	struct bnxt_filter_base *fltr_base;
	struct bnxt_ntuple_filter *fltr;

	rcu_read_lock();
	fltr_base = bnxt_get_one_fltr_rcu(bp, bp->ntp_fltr_hash_tbl,
					  BNXT_NTP_FLTR_HASH_SIZE,
					  fs->location);
	if (!fltr_base) {
		rcu_read_unlock();
		return -ENOENT;
	}

	fltr = container_of(fltr_base, struct bnxt_ntuple_filter, base);
	rcu_read_unlock();

	if (!(fltr->base.flags & BNXT_ACT_NO_AGING))
		return -EINVAL;

	bnxt_hwrm_cfa_ntuple_filter_free(bp, fltr);
	bnxt_del_ntp_filter(bp, fltr);

	return 0;
}

...