net: provide a default dev->ethtool_ops

Instead of forcing device drivers to provide empty ethtool_ops or tweak
net/core/ethtool.c again, we could provide a generic ethtool_ops.

This occurred to me when I wanted to add GSO support to GRE tunnels.
ethtool -k support should be generic for all drivers.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Maciej Żenczykowski <maze@google.com>
Reviewed-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 4 insertions, 12 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index bb42eb161969..bbda81997f4f 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5974,6 +5974,8 @@ struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
         return queue;
 }
 
+static const struct ethtool_ops default_ethtool_ops;
+
 /**
  *      alloc_netdev_mqs - allocate network device
  *      @sizeof_priv:   size of private data to allocate space for
@@ -6061,6 +6063,8 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
 
         strcpy(dev->name, name);
         dev->group = INIT_NETDEV_GROUP;
+        if (!dev->ethtool_ops)
+                dev->ethtool_ops = &default_ethtool_ops;
         return dev;
 
 free_all:
diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index cbf033dcaf1f..4d64cc2e3fa9 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -1426,18 +1426,6 @@ int dev_ethtool(struct net *net, struct ifreq *ifr)
         if (copy_from_user(&ethcmd, useraddr, sizeof(ethcmd)))
                 return -EFAULT;
 
-        if (!dev->ethtool_ops) {
-                /* A few commands do not require any driver support,
-                 * are unprivileged, and do not change anything, so we
-                 * can take a shortcut to them. */
-                if (ethcmd == ETHTOOL_GDRVINFO)
-                        return ethtool_get_drvinfo(dev, useraddr);
-                else if (ethcmd == ETHTOOL_GET_TS_INFO)
-                        return ethtool_get_ts_info(dev, useraddr);
-                else
-                        return -EOPNOTSUPP;
-        }
-
         /* Allow some commands to be done by anyone */
         switch (ethcmd) {
         case ETHTOOL_GSET: