hv_netvsc: add ethtool support for set and get of settings

This patch allows the user to set and retrieve speed and duplex of the
hv_netvsc device via ethtool.

Example:
$ ethtool eth0
Settings for eth0:
...
    Speed: Unknown!
    Duplex: Unknown! (255)
...
$ ethtool -s eth0 speed 1000 duplex full
$ ethtool eth0
Settings for eth0:
...
    Speed: 1000Mb/s
    Duplex: Full
...

This is based on patches by Roopa Prabhu and Nikolay Aleksandrov.

Signed-off-by: Simon Xiao <sixiao@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 56 insertions, 0 deletions

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 2b6595e24f43..08608499fa17 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -799,6 +799,58 @@ static int netvsc_set_channels(struct net_device *net,
         goto do_set;
 }
 
+static bool netvsc_validate_ethtool_ss_cmd(const struct ethtool_cmd *cmd)
+{
+        struct ethtool_cmd diff1 = *cmd;
+        struct ethtool_cmd diff2 = {};
+
+        ethtool_cmd_speed_set(&diff1, 0);
+        diff1.duplex = 0;
+        /* advertising and cmd are usually set */
+        diff1.advertising = 0;
+        diff1.cmd = 0;
+        /* We set port to PORT_OTHER */
+        diff2.port = PORT_OTHER;
+
+        return !memcmp(&diff1, &diff2, sizeof(diff1));
+}
+
+static void netvsc_init_settings(struct net_device *dev)
+{
+        struct net_device_context *ndc = netdev_priv(dev);
+
+        ndc->speed = SPEED_UNKNOWN;
+        ndc->duplex = DUPLEX_UNKNOWN;
+}
+
+static int netvsc_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
+{
+        struct net_device_context *ndc = netdev_priv(dev);
+
+        ethtool_cmd_speed_set(cmd, ndc->speed);
+        cmd->duplex = ndc->duplex;
+        cmd->port = PORT_OTHER;
+
+        return 0;
+}
+
+static int netvsc_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
+{
+        struct net_device_context *ndc = netdev_priv(dev);
+        u32 speed;
+
+        speed = ethtool_cmd_speed(cmd);
+        if (!ethtool_validate_speed(speed) ||
+            !ethtool_validate_duplex(cmd->duplex) ||
+            !netvsc_validate_ethtool_ss_cmd(cmd))
+                return -EINVAL;
+
+        ndc->speed = speed;
+        ndc->duplex = cmd->duplex;
+
+        return 0;
+}
+
 static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 {
         struct net_device_context *ndevctx = netdev_priv(ndev);
@@ -923,6 +975,8 @@ static const struct ethtool_ops ethtool_ops = {
         .get_channels   = netvsc_get_channels,
         .set_channels   = netvsc_set_channels,
         .get_ts_info    = ethtool_op_get_ts_info,
+        .get_settings   = netvsc_get_settings,
+        .set_settings   = netvsc_set_settings,
 };
 
 static const struct net_device_ops device_ops = {
@@ -1115,6 +1169,8 @@ static int netvsc_probe(struct hv_device *dev,
         netif_set_real_num_tx_queues(net, nvdev->num_chn);
         netif_set_real_num_rx_queues(net, nvdev->num_chn);
 
+        netvsc_init_settings(net);
+
         ret = register_netdev(net);
         if (ret != 0) {
                 pr_err("Unable to register netdev.\n");