Re: [PATCH v9 net-next 09/11] net: dsa: microchip: add support for port mirror operations

Vladimir Oltean
2022-03-18T11:00:43Z

On Fri, Mar 18, 2022 at 02:25:38PM +0530, Prasanna Vengateshan wrote:
> Added support for port_mirror_add() and port_mirror_del operations
>
> Sniffing is limited to one port & alert the user if any new
> sniffing port is selected
>
> Signed-off-by: Prasanna Vengateshan <prasanna.vengateshan@microchip.com>
> Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
> ---
> drivers/net/dsa/microchip/lan937x_main.c | 84 ++++++++++++++++++++++++
> 1 file changed, 84 insertions(+)
>
> diff --git a/drivers/net/dsa/microchip/lan937x_main.c b/drivers/net/dsa/microchip/lan937x_main.c
> index c54aba6a05b5..5a57a2ce8992 100644
> --- a/drivers/net/dsa/microchip/lan937x_main.c
> +++ b/drivers/net/dsa/microchip/lan937x_main.c
> @@ -98,6 +98,88 @@ static void lan937x_port_stp_state_set(struct dsa_switch *ds, int port,
> ksz_update_port_member(dev, port);
> }
>
> +static int lan937x_port_mirror_add(struct dsa_switch *ds, int port,
> + struct dsa_mall_mirror_tc_entry *mirror,
> + bool ingress)

This function gained a new extack argument yesterday => your patch
doesn't compile. Maybe you could even use the extack to propagate the
"existing sniffer port" error.

> +{
> + struct ksz_device *dev = ds->priv;
> + int ret, p;
> + u8 data;
> +
> + /* Limit to one sniffer port
> + * Check if any of the port is already set for sniffing
> + * If yes, instruct the user to remove the previous entry & exit
> + */
> + for (p = 0; p < dev->port_cnt; p++) {
> + /* Skip the current sniffing port */
> + if (p == mirror->to_local_port)
> + continue;
> +
> + ret = lan937x_pread8(dev, p, P_MIRROR_CTRL, &data);
> + if (ret < 0)
> + return ret;
> +
> + if (data & PORT_MIRROR_SNIFFER) {
> + dev_err(dev->dev,
> + "Delete existing rules towards %s & try\n",
> + dsa_to_port(ds, p)->name);
> + return -EBUSY;
> + }
> + }
> +
> + /* Configure ingress/egress mirroring */
> + if (ingress)
> + ret = lan937x_port_cfg(dev, port, P_MIRROR_CTRL, PORT_MIRROR_RX,
> + true);
> + else
> + ret = lan937x_port_cfg(dev, port, P_MIRROR_CTRL, PORT_MIRROR_TX,
> + true);
> + if (ret < 0)
> + return ret;
> +
> + /* Configure sniffer port as other ports do not have
> + * PORT_MIRROR_SNIFFER is set
> + */
> + ret = lan937x_port_cfg(dev, mirror->to_local_port, P_MIRROR_CTRL,
> + PORT_MIRROR_SNIFFER, true);
> + if (ret < 0)
> + return ret;
> +
> + return lan937x_cfg(dev, S_MIRROR_CTRL, SW_MIRROR_RX_TX, false);
> +}
> +
> +static void lan937x_port_mirror_del(struct dsa_switch *ds, int port,
> + struct dsa_mall_mirror_tc_entry *mirror)
> +{
> + struct ksz_device *dev = ds->priv;
> + bool in_use = false;
> + u8 data;
> + int p;
> +
> + /* clear ingress/egress mirroring port */
> + if (mirror->ingress)
> + lan937x_port_cfg(dev, port, P_MIRROR_CTRL, PORT_MIRROR_RX,
> + false);
> + else
> + lan937x_port_cfg(dev, port, P_MIRROR_CTRL, PORT_MIRROR_TX,
> + false);
> +
> + /* Check if any of the port is still referring to sniffer port */
> + for (p = 0; p < dev->port_cnt; p++) {
> + lan937x_pread8(dev, p, P_MIRROR_CTRL, &data);
> +
> + if ((data & (PORT_MIRROR_RX | PORT_MIRROR_TX))) {
> + in_use = true;
> + break;
> + }
> + }
> +
> + /* delete sniffing if there are no other mirroring rule exist */
> + if (!in_use)
> + lan937x_port_cfg(dev, mirror->to_local_port, P_MIRROR_CTRL,
> + PORT_MIRROR_SNIFFER, false);
> +}
> +
> static void lan937x_config_cpu_port(struct dsa_switch *ds)
> {
> struct ksz_device *dev = ds->priv;
> @@ -508,6 +590,8 @@ const struct dsa_switch_ops lan937x_switch_ops = {
> .port_bridge_leave = ksz_port_bridge_leave,
> .port_stp_state_set = lan937x_port_stp_state_set,
> .port_fast_age = ksz_port_fast_age,
> + .port_mirror_add = lan937x_port_mirror_add,
> + .port_mirror_del = lan937x_port_mirror_del,
> .port_max_mtu = lan937x_get_max_mtu,
> .port_change_mtu = lan937x_change_mtu,
> .phylink_get_caps = lan937x_phylink_get_caps,
> --
> 2.30.2
>