Subject: Re: [PATCH v4] ice: Add get/set hw address for VFs using devlink commands

From: Jiri Pirko <[email-masked]>
Date: Tue, 27 Feb 2024 17:13:09 +0100

Sat, Feb 24, 2024 at 01:44:06PM CET, [email-masked] wrote:
>Changing the MAC address of the VFs are not available
>via devlink. Add the function handlers to set and get
>the HW address for the VFs.
>
>Signed-off-by: Karthik Sundaravel <[email-masked]>
>---
> drivers/net/ethernet/intel/ice/ice_devlink.c | 88 +++++++++++++++++++-
> 1 file changed, 87 insertions(+), 1 deletion(-)
>
>diff --git a/drivers/net/ethernet/intel/ice/ice_devlink.c b/drivers/net/ethernet/intel/ice/ice_devlink.c
>index 80dc5445b50d..c3813edd6a76 100644
>--- a/drivers/net/ethernet/intel/ice/ice_devlink.c
>+++ b/drivers/net/ethernet/intel/ice/ice_devlink.c
>@@ -1576,6 +1576,91 @@ void ice_devlink_destroy_pf_port(struct ice_pf *pf)
> 	devlink_port_unregister(&pf->devlink_port);
> }
> 
>+/**
>+ * ice_devlink_port_get_vf_mac_address - .port_fn_hw_addr_get devlink handler
>+ * @port: devlink port structure
>+ * @hw_addr: MAC address of the port
>+ * @hw_addr_len: length of MAC address
>+ * @extack: extended netdev ack structure
>+ *
>+ * Callback for the devlink .port_fn_hw_addr_get operation
>+ * Return: zero on success or an error code on failure.
>+ */
>+
>+static int ice_devlink_port_get_vf_mac_address(struct devlink_port *port,
>+					       u8 *hw_addr, int *hw_addr_len,
>+					       struct netlink_ext_ack *extack)
>+{
>+	struct devlink_port_attrs *attrs = &port->attrs;
>+	struct devlink_port_pci_vf_attrs *pci_vf;
>+	struct devlink *devlink = port->devlink;
>+	struct ice_pf *pf;
>+	struct ice_vf *vf;
>+	int vf_id;
>+
>+	pf = devlink_priv(devlink);
>+	if (attrs->flavour == DEVLINK_PORT_FLAVOUR_PCI_VF) {
>+		pci_vf = &attrs->pci_vf;
>+		vf_id = pci_vf->vf;
>+	} else {
>+		NL_SET_ERR_MSG_MOD(extack, "Unable to get the vf id");
>+		return -EADDRNOTAVAIL;
>+	}
>+	vf = ice_get_vf_by_id(pf, vf_id);
>+	if (!vf) {
>+		NL_SET_ERR_MSG_MOD(extack, "Unable to get the vf");
>+		return -EINVAL;
>+	}
>+	ether_addr_copy(hw_addr, vf->dev_lan_addr);
>+	*hw_addr_len = ETH_ALEN;
>+
>+	ice_put_vf(vf);
>+	return 0;
>+}
>+
>+/**
>+ * ice_devlink_port_set_vf_mac_address - .port_fn_hw_addr_set devlink handler
>+ * @port: devlink port structure
>+ * @hw_addr: MAC address of the port
>+ * @hw_addr_len: length of MAC address
>+ * @extack: extended netdev ack structure
>+ *
>+ * Callback for the devlink .port_fn_hw_addr_set operation
>+ * Return: zero on success or an error code on failure.
>+ */
>+static int ice_devlink_port_set_vf_mac_address(struct devlink_port *port,

Better to have "fn" in the name of the function, so it is clear this
sets the mac of function itself.

>+					       const u8 *hw_addr,
>+					       int hw_addr_len,
>+					       struct netlink_ext_ack *extack)
>+{
>+	struct net_device *netdev = port->type_eth.netdev;
>+	struct devlink_port_attrs *attrs = &port->attrs;
>+	struct devlink_port_pci_vf_attrs *pci_vf;
>+	u8 mac[ETH_ALEN];
>+	int vf_id;
>+
>+	if (attrs->flavour == DEVLINK_PORT_FLAVOUR_PCI_VF) {
>+		pci_vf = &attrs->pci_vf;
>+		vf_id = pci_vf->vf;
>+	} else {
>+		NL_SET_ERR_MSG_MOD(extack, "Unable to get the vf id");

How exactly this can happen? I'm pretty sure it can't.

>+		return -EADDRNOTAVAIL;
>+	}
>+
>+	if (!netdev) {

How exactly this can happen? I'm pretty sure it can't.

>+		NL_SET_ERR_MSG_MOD(extack, "Unable to get the netdev");
>+		return -EADDRNOTAVAIL;
>+	}
>+	ether_addr_copy(mac, hw_addr);
>+
>+	return ice_set_vf_mac(netdev, vf_id, mac);

It's misleading to call ice_set_vf_mac like this. It is originally used
by legacy ip vf api, where the netdev is the PF netdev. Here you pass
devlink port representor netdev. Internally ice_set_vf_mac() gets
pointer to struct ice_pf.

Could you please use:
struct ice_pf *pf = devlink_priv(devlink);
and pass it to some variant of ice_set_vf_mac() function?

pw-bot: cr

>+}
>+
>+static const struct devlink_port_ops ice_devlink_vf_port_ops = {
>+	.port_fn_hw_addr_get = ice_devlink_port_get_vf_mac_address,
>+	.port_fn_hw_addr_set = ice_devlink_port_set_vf_mac_address,
>+};
>+
> /**
>  * ice_devlink_create_vf_port - Create a devlink port for this VF
>  * @vf: the VF to create a port for
>@@ -1611,7 +1696,8 @@ int ice_devlink_create_vf_port(struct ice_vf *vf)
> 	devlink_port_attrs_set(devlink_port, &attrs);
> 	devlink = priv_to_devlink(pf);
> 
>-	err = devlink_port_register(devlink, devlink_port, vsi->idx);
>+	err = devlink_port_register_with_ops(devlink, devlink_port,
>+					     vsi->idx, &ice_devlink_vf_port_ops);
> 	if (err) {
> 		dev_err(dev, "Failed to create devlink port for VF %d, error %d\n",
> 			vf->vf_id, err);
>-- 
>2.39.3 (Apple Git-145)
>