net/ethtool: Add current supported tunable options

Add strings array of the current supported tunable options.

Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com>
Reviewed-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index 0594933..cd67aec 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -215,6 +215,11 @@
 	ETHTOOL_ID_UNSPEC,
 	ETHTOOL_RX_COPYBREAK,
 	ETHTOOL_TX_COPYBREAK,
+	/*
+	 * Add your fresh new tubale attribute above and remember to update
+	 * tunable_strings[] in net/core/ethtool.c
+	 */
+	__ETHTOOL_TUNABLE_COUNT,
 };
 
 enum tunable_type_id {
@@ -545,6 +550,7 @@
 	ETH_SS_NTUPLE_FILTERS,
 	ETH_SS_FEATURES,
 	ETH_SS_RSS_HASH_FUNCS,
+	ETH_SS_TUNABLES,
 };
 
 /**
diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index eb0c3ac..b495ab1 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -106,6 +106,13 @@
 	[ETH_RSS_HASH_XOR_BIT] =	"xor",
 };
 
+static const char
+tunable_strings[__ETHTOOL_TUNABLE_COUNT][ETH_GSTRING_LEN] = {
+	[ETHTOOL_ID_UNSPEC]     = "Unspec",
+	[ETHTOOL_RX_COPYBREAK]	= "rx-copybreak",
+	[ETHTOOL_TX_COPYBREAK]	= "tx-copybreak",
+};
+
 static int ethtool_get_features(struct net_device *dev, void __user *useraddr)
 {
 	struct ethtool_gfeatures cmd = {
@@ -194,6 +201,9 @@
 	if (sset == ETH_SS_RSS_HASH_FUNCS)
 		return ARRAY_SIZE(rss_hash_func_strings);
 
+	if (sset == ETH_SS_TUNABLES)
+		return ARRAY_SIZE(tunable_strings);
+
 	if (ops->get_sset_count && ops->get_strings)
 		return ops->get_sset_count(dev, sset);
 	else
@@ -211,6 +221,8 @@
 	else if (stringset == ETH_SS_RSS_HASH_FUNCS)
 		memcpy(data, rss_hash_func_strings,
 		       sizeof(rss_hash_func_strings));
+	else if (stringset == ETH_SS_TUNABLES)
+		memcpy(data, tunable_strings, sizeof(tunable_strings));
 	else
 		/* ops->get_strings is valid because checked earlier */
 		ops->get_strings(dev, stringset, data);