[PATCH net-next 6/8] netdevsim: Simulate get/set hardware address of a PCI port

[Parav Pandit <parav@nvidia.com>]

Allow users to get/set hardware address for the PCI port.

Below example creates one devlink port, queries a port, sets a
hardware address.

Example of a PCI SF port which supports a port function hw_addr set:
Create a device with ID=10 and one physical port.
$ echo "10 1" > /sys/bus/netdevsim/new_device
$ devlink port show
netdevsim/netdevsim10/0: type eth netdev eni10np1 flavour physical port 1 splittable false

$ devlink port add netdevsim/netdevsim10/10 flavour pcipf pfnum 0
$ devlink port show netdevsim/netdevsim10/10
netdevsim/netdevsim10/10: type eth netdev eni10npf0 flavour pcipf controller 0 pfnum 0 external false splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive

$ devlink port function set netdevsim/netdevsim10/10 hw_addr 00:11:22:33:44:55

$ devlink port show netdevsim/netdevsim10/10 -jp
{
    "port": {
        "netdevsim/netdevsim10/11": {
            "type": "eth",
            "netdev": "eni10npf0",
            "flavour": "pcisf",
            "controller": 0,
            "pfnum": 0,
            "sfnum": 44,
            "external": true,
            "splittable": false,
            "function": {
                "hw_addr": "00:11:22:33:44:55"
            }
        }
    }
}

Signed-off-by: Parav Pandit <parav@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
---
 drivers/net/netdevsim/dev.c           |  2 ++
 drivers/net/netdevsim/netdevsim.h     |  6 ++++
 drivers/net/netdevsim/port_function.c | 44 +++++++++++++++++++++++++++
 3 files changed, 52 insertions(+)

diff --git a/drivers/net/netdevsim/dev.c b/drivers/net/netdevsim/dev.c
index e3b81c8b5125..ef2e293f358b 100644
--- a/drivers/net/netdevsim/dev.c
+++ b/drivers/net/netdevsim/dev.c
@@ -886,6 +886,8 @@ static const struct devlink_ops nsim_dev_devlink_ops = {
 	.trap_policer_counter_get = nsim_dev_devlink_trap_policer_counter_get,
 	.port_new = nsim_dev_devlink_port_new,
 	.port_del = nsim_dev_devlink_port_del,
+	.port_function_hw_addr_get = nsim_dev_port_function_hw_addr_get,
+	.port_function_hw_addr_set = nsim_dev_port_function_hw_addr_set,
 };
 
 #define NSIM_DEV_MAX_MACS_DEFAULT 32
diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h
index aec3c4d5fda7..8dc8f4e5dcd8 100644
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -302,3 +302,9 @@ int nsim_dev_devlink_port_new(struct devlink *devlink, const struct devlink_port
 			      struct netlink_ext_ack *extack);
 int nsim_dev_devlink_port_del(struct devlink *devlink, unsigned int port_index,
 			      struct netlink_ext_ack *extack);
+int nsim_dev_port_function_hw_addr_get(struct devlink *devlink, struct devlink_port *port,
+				       u8 *hw_addr, int *hw_addr_len,
+				       struct netlink_ext_ack *extack);
+int nsim_dev_port_function_hw_addr_set(struct devlink *devlink, struct devlink_port *port,
+				       const u8 *hw_addr, int hw_addr_len,
+				       struct netlink_ext_ack *extack);
diff --git a/drivers/net/netdevsim/port_function.c b/drivers/net/netdevsim/port_function.c
index 9a1634898c7d..0053f6f6d530 100644
--- a/drivers/net/netdevsim/port_function.c
+++ b/drivers/net/netdevsim/port_function.c
@@ -15,6 +15,7 @@ struct nsim_port_function {
 	u32 controller;
 	u16 pfnum;
 	struct nsim_port_function *pf_port; /* Valid only for SF port */
+	u8 hw_addr[ETH_ALEN];
 };
 
 void nsim_dev_port_function_init(struct nsim_dev *nsim_dev)
@@ -335,3 +336,46 @@ void nsim_dev_port_function_disable(struct nsim_dev *nsim_dev)
 		nsim_devlink_port_function_free(nsim_dev, port);
 	}
 }
+
+static struct nsim_port_function *nsim_dev_to_port_function(struct nsim_dev *nsim_dev,
+							    struct devlink_port *dl_port)
+{
+	if (nsim_dev_port_index_internal(nsim_dev, dl_port->index))
+		return ERR_PTR(-EOPNOTSUPP);
+	return container_of(dl_port, struct nsim_port_function, dl_port);
+}
+
+int nsim_dev_port_function_hw_addr_get(struct devlink *devlink, struct devlink_port *dl_port,
+				       u8 *hw_addr, int *hw_addr_len,
+				       struct netlink_ext_ack *extack)
+{
+	struct nsim_dev *nsim_dev = devlink_priv(devlink);
+	struct nsim_port_function *port;
+
+	port = nsim_dev_to_port_function(nsim_dev, dl_port);
+	if (IS_ERR(port))
+		return PTR_ERR(port);
+
+	memcpy(hw_addr, port->hw_addr, ETH_ALEN);
+	*hw_addr_len = ETH_ALEN;
+	return 0;
+}
+
+int nsim_dev_port_function_hw_addr_set(struct devlink *devlink, struct devlink_port *dl_port,
+				       const u8 *hw_addr, int hw_addr_len,
+				       struct netlink_ext_ack *extack)
+{
+	struct nsim_dev *nsim_dev = devlink_priv(devlink);
+	struct nsim_port_function *port;
+
+	if (hw_addr_len != ETH_ALEN) {
+		NL_SET_ERR_MSG_MOD(extack, "Hardware address must be 6 bytes long");
+		return -EOPNOTSUPP;
+	}
+	port = nsim_dev_to_port_function(nsim_dev, dl_port);
+	if (IS_ERR(port))
+		return PTR_ERR(port);
+
+	memcpy(port->hw_addr, hw_addr, ETH_ALEN);
+	return 0;
+}
-- 
2.26.2