ethtool: Call ethtool's get/set_settings callbacks with cleaned data

This makes sure that when a driver calls the ethtool's
get/set_settings() callback of another driver, the data passed to it
is clean. This guarantees that speed_hi will be zeroed correctly if
the called callback doesn't explicitely set it: we are sure we don't
get a corrupted speed from the underlying driver. We also take care of
setting the cmd field appropriately (ETHTOOL_GSET/SSET).

This applies to dev_ethtool_get_settings(), which now makes sure it
sets up that ethtool command parameter correctly before passing it to
drivers. This also means that whoever calls dev_ethtool_get_settings()
does not have to clean the ethtool command parameter. This function
also becomes an exported symbol instead of an inline.

All drivers visible to make allyesconfig under x86_64 have been
updated.

Signed-off-by: David Decotigny <decot@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 7e6e0a8..4194a20 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -744,7 +744,9 @@
 /**
  * struct ethtool_ops - optional netdev operations
  * @get_settings: Get various device settings including Ethernet link
- *	settings.  Returns a negative error code or zero.
+ *	settings. The @cmd parameter is expected to have been cleared
+ *	before get_settings is called. Returns a negative error code or
+ *	zero.
  * @set_settings: Set various device settings including Ethernet link
  *	settings.  Returns a negative error code or zero.
  * @get_drvinfo: Report driver/device information.  Should only set the
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index e03af35..d5de66a 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2597,13 +2597,8 @@
 
 extern struct pernet_operations __net_initdata loopback_net_ops;
 
-static inline int dev_ethtool_get_settings(struct net_device *dev,
-					   struct ethtool_cmd *cmd)
-{
-	if (!dev->ethtool_ops || !dev->ethtool_ops->get_settings)
-		return -EOPNOTSUPP;
-	return dev->ethtool_ops->get_settings(dev, cmd);
-}
+int dev_ethtool_get_settings(struct net_device *dev,
+			     struct ethtool_cmd *cmd);
 
 static inline u32 dev_ethtool_get_rx_csum(struct net_device *dev)
 {