ethtool: add tunnel info interface

Add an interface to report offloaded UDP ports via ethtool netlink.

Now that core takes care of tracking which UDP tunnel ports the NICs
are aware of we can quite easily export this information out to
user space.

The responsibility of writing the netlink dumps is split between
ethtool code and udp_tunnel_nic.c - since udp_tunnel module may
not always be loaded, yet we should always report the capabilities
of the NIC.

$ ethtool --show-tunnels eth0
Tunnel information for eth0:
  UDP port table 0:
    Size: 4
    Types: vxlan
    No entries
  UDP port table 1:
    Size: 4
    Types: geneve, vxlan-gpe
    Entries (1):
        port 1230, vxlan-gpe

v4:
 - back to v2, build fix is now directly in udp_tunnel.h
v3:
 - don't compile ETHTOOL_MSG_TUNNEL_INFO_GET in if CONFIG_INET
   not set.
v2:
 - fix string set count,
 - reorder enums in the uAPI,
 - fix type of ETHTOOL_A_TUNNEL_UDP_TABLE_TYPES to bitset
   in docs and comments.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 78 insertions, 0 deletions

diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h
index ee34619e4cfa..dd20ce99740c 100644
--- a/include/net/udp_tunnel.h
+++ b/include/net/udp_tunnel.h
@@ -255,6 +255,10 @@ struct udp_tunnel_nic_ops {
 	void (*add_port)(struct net_device *dev, struct udp_tunnel_info *ti);
 	void (*del_port)(struct net_device *dev, struct udp_tunnel_info *ti);
 	void (*reset_ntf)(struct net_device *dev);
+
+	size_t (*dump_size)(struct net_device *dev, unsigned int table);
+	int (*dump_write)(struct net_device *dev, unsigned int table,
+			  struct sk_buff *skb);
 };
 
 #ifdef CONFIG_INET
@@ -318,4 +322,21 @@ static inline void udp_tunnel_nic_reset_ntf(struct net_device *dev)
 	if (udp_tunnel_nic_ops)
 		udp_tunnel_nic_ops->reset_ntf(dev);
 }
+
+static inline size_t
+udp_tunnel_nic_dump_size(struct net_device *dev, unsigned int table)
+{
+	if (!udp_tunnel_nic_ops)
+		return 0;
+	return udp_tunnel_nic_ops->dump_size(dev, table);
+}
+
+static inline int
+udp_tunnel_nic_dump_write(struct net_device *dev, unsigned int table,
+			  struct sk_buff *skb)
+{
+	if (!udp_tunnel_nic_ops)
+		return 0;
+	return udp_tunnel_nic_ops->dump_write(dev, table, skb);
+}
 #endif
diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index 60856e0f9618..b4f2d134e713 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -669,6 +669,7 @@ enum ethtool_link_ext_substate_cable_issue {
  * @ETH_SS_SOF_TIMESTAMPING: SOF_TIMESTAMPING_* flags
  * @ETH_SS_TS_TX_TYPES: timestamping Tx types
  * @ETH_SS_TS_RX_FILTERS: timestamping Rx filters
+ * @ETH_SS_UDP_TUNNEL_TYPES: UDP tunnel types
  */
 enum ethtool_stringset {
 	ETH_SS_TEST		= 0,
@@ -686,6 +687,7 @@ enum ethtool_stringset {
 	ETH_SS_SOF_TIMESTAMPING,
 	ETH_SS_TS_TX_TYPES,
 	ETH_SS_TS_RX_FILTERS,
+	ETH_SS_UDP_TUNNEL_TYPES,
 
 	/* add new constants above here */
 	ETH_SS_COUNT
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index c12ce4df4b6b..5dcd24cb33ea 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -41,6 +41,7 @@ enum {
 	ETHTOOL_MSG_TSINFO_GET,
 	ETHTOOL_MSG_CABLE_TEST_ACT,
 	ETHTOOL_MSG_CABLE_TEST_TDR_ACT,
+	ETHTOOL_MSG_TUNNEL_INFO_GET,
 
 	/* add new constants above here */
 	__ETHTOOL_MSG_USER_CNT,
@@ -556,6 +557,60 @@ enum {
 	ETHTOOL_A_CABLE_TEST_TDR_NTF_MAX = __ETHTOOL_A_CABLE_TEST_TDR_NTF_CNT - 1
 };
 
+/* TUNNEL INFO */
+
+enum {
+	ETHTOOL_UDP_TUNNEL_TYPE_VXLAN,
+	ETHTOOL_UDP_TUNNEL_TYPE_GENEVE,
+	ETHTOOL_UDP_TUNNEL_TYPE_VXLAN_GPE,
+
+	__ETHTOOL_UDP_TUNNEL_TYPE_CNT
+};
+
+enum {
+	ETHTOOL_A_TUNNEL_UDP_ENTRY_UNSPEC,
+
+	ETHTOOL_A_TUNNEL_UDP_ENTRY_PORT,		/* be16 */
+	ETHTOOL_A_TUNNEL_UDP_ENTRY_TYPE,		/* u32 */
+
+	/* add new constants above here */
+	__ETHTOOL_A_TUNNEL_UDP_ENTRY_CNT,
+	ETHTOOL_A_TUNNEL_UDP_ENTRY_MAX = (__ETHTOOL_A_TUNNEL_UDP_ENTRY_CNT - 1)
+};
+
+enum {
+	ETHTOOL_A_TUNNEL_UDP_TABLE_UNSPEC,
+
+	ETHTOOL_A_TUNNEL_UDP_TABLE_SIZE,		/* u32 */
+	ETHTOOL_A_TUNNEL_UDP_TABLE_TYPES,		/* bitset */
+	ETHTOOL_A_TUNNEL_UDP_TABLE_ENTRY,		/* nest - _UDP_ENTRY_* */
+
+	/* add new constants above here */
+	__ETHTOOL_A_TUNNEL_UDP_TABLE_CNT,
+	ETHTOOL_A_TUNNEL_UDP_TABLE_MAX = (__ETHTOOL_A_TUNNEL_UDP_TABLE_CNT - 1)
+};
+
+enum {
+	ETHTOOL_A_TUNNEL_UDP_UNSPEC,
+
+	ETHTOOL_A_TUNNEL_UDP_TABLE,			/* nest - _UDP_TABLE_* */
+
+	/* add new constants above here */
+	__ETHTOOL_A_TUNNEL_UDP_CNT,
+	ETHTOOL_A_TUNNEL_UDP_MAX = (__ETHTOOL_A_TUNNEL_UDP_CNT - 1)
+};
+
+enum {
+	ETHTOOL_A_TUNNEL_INFO_UNSPEC,
+	ETHTOOL_A_TUNNEL_INFO_HEADER,			/* nest - _A_HEADER_* */
+
+	ETHTOOL_A_TUNNEL_INFO_UDP_PORTS,		/* nest - _UDP_TABLE */
+
+	/* add new constants above here */
+	__ETHTOOL_A_TUNNEL_INFO_CNT,
+	ETHTOOL_A_TUNNEL_INFO_MAX = (__ETHTOOL_A_TUNNEL_INFO_CNT - 1)
+};
+
 /* generic netlink info */
 #define ETHTOOL_GENL_NAME "ethtool"
 #define ETHTOOL_GENL_VERSION 1