ethtool: add a new command for reading standard stats

Add an interface for reading standard stats, including
stats which don't have a corresponding control interface.

Start with IEEE 802.3 PHY stats. There seems to be only
one stat to expose there.

Define API to not require user space changes when new
stats or groups are added. Groups are based on bitset,
stats have a string set associated.

v1: wrap stats in a nest

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

3 files changed, 61 insertions, 0 deletions

diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 112a85b57f1f..2d5455eedbf4 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -250,6 +250,13 @@ static inline void ethtool_stats_init(u64 *stats, unsigned int n)
 		stats[n] = ETHTOOL_STAT_NOT_SET;
 }
 
+/* Basic IEEE 802.3 PHY statistics (30.3.2.1.*), not otherwise exposed
+ * via a more targeted API.
+ */
+struct ethtool_eth_phy_stats {
+	u64 SymbolErrorDuringCarrier;
+};
+
 /**
  * struct ethtool_pause_stats - statistics for IEEE 802.3x pause frames
  * @tx_pause_frames: transmitted pause frame count. Reported to user space
@@ -487,6 +494,7 @@ struct ethtool_module_eeprom {
  * @get_module_eeprom_by_page: Get a region of plug-in module EEPROM data from
  *	specified page. Returns a negative error code or the amount of bytes
  *	read.
+ * @get_eth_phy_stats: Query some of the IEEE 802.3 PHY statistics.
  *
  * All operations are optional (i.e. the function pointer may be set
  * to %NULL) and callers must take this into account.  Callers must
@@ -597,6 +605,8 @@ struct ethtool_ops {
 	int	(*get_module_eeprom_by_page)(struct net_device *dev,
 					     const struct ethtool_module_eeprom *page,
 					     struct netlink_ext_ack *extack);
+	void	(*get_eth_phy_stats)(struct net_device *dev,
+				     struct ethtool_eth_phy_stats *phy_stats);
 };
 
 int ethtool_check_ops(const struct ethtool_ops *ops);
diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index f91e079e3108..190ae6e03918 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -669,6 +669,8 @@ enum ethtool_link_ext_substate_cable_issue {
  * @ETH_SS_TS_TX_TYPES: timestamping Tx types
  * @ETH_SS_TS_RX_FILTERS: timestamping Rx filters
  * @ETH_SS_UDP_TUNNEL_TYPES: UDP tunnel types
+ * @ETH_SS_STATS_STD: standardized stats
+ * @ETH_SS_STATS_ETH_PHY: names of IEEE 802.3 PHY statistics
  *
  * @ETH_SS_COUNT: number of defined string sets
  */
@@ -689,6 +691,8 @@ enum ethtool_stringset {
 	ETH_SS_TS_TX_TYPES,
 	ETH_SS_TS_RX_FILTERS,
 	ETH_SS_UDP_TUNNEL_TYPES,
+	ETH_SS_STATS_STD,
+	ETH_SS_STATS_ETH_PHY,
 
 	/* 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 3a2b31ccbc5b..a54cfe625f34 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -45,6 +45,7 @@ enum {
 	ETHTOOL_MSG_FEC_GET,
 	ETHTOOL_MSG_FEC_SET,
 	ETHTOOL_MSG_MODULE_EEPROM_GET,
+	ETHTOOL_MSG_STATS_GET,
 
 	/* add new constants above here */
 	__ETHTOOL_MSG_USER_CNT,
@@ -86,6 +87,7 @@ enum {
 	ETHTOOL_MSG_FEC_GET_REPLY,
 	ETHTOOL_MSG_FEC_NTF,
 	ETHTOOL_MSG_MODULE_EEPROM_GET_REPLY,
+	ETHTOOL_MSG_STATS_GET_REPLY,
 
 	/* add new constants above here */
 	__ETHTOOL_MSG_KERNEL_CNT,
@@ -679,6 +681,51 @@ enum {
 	ETHTOOL_A_MODULE_EEPROM_MAX = (__ETHTOOL_A_MODULE_EEPROM_CNT - 1)
 };
 
+/* STATS */
+
+enum {
+	ETHTOOL_A_STATS_UNSPEC,
+	ETHTOOL_A_STATS_PAD,
+	ETHTOOL_A_STATS_HEADER,			/* nest - _A_HEADER_* */
+	ETHTOOL_A_STATS_GROUPS,			/* bitset */
+
+	ETHTOOL_A_STATS_GRP,			/* nest - _A_STATS_GRP_* */
+
+	/* add new constants above here */
+	__ETHTOOL_A_STATS_CNT,
+	ETHTOOL_A_STATS_MAX = (__ETHTOOL_A_STATS_CNT - 1)
+};
+
+enum {
+	ETHTOOL_STATS_ETH_PHY,
+
+	/* add new constants above here */
+	__ETHTOOL_STATS_CNT
+};
+
+enum {
+	ETHTOOL_A_STATS_GRP_UNSPEC,
+	ETHTOOL_A_STATS_GRP_PAD,
+
+	ETHTOOL_A_STATS_GRP_ID,			/* u32 */
+	ETHTOOL_A_STATS_GRP_SS_ID,		/* u32 */
+
+	ETHTOOL_A_STATS_GRP_STAT,		/* nest */
+
+	/* add new constants above here */
+	__ETHTOOL_A_STATS_GRP_CNT,
+	ETHTOOL_A_STATS_GRP_MAX = (__ETHTOOL_A_STATS_CNT - 1)
+};
+
+enum {
+	/* 30.3.2.1.5 aSymbolErrorDuringCarrier */
+	ETHTOOL_A_STATS_ETH_PHY_5_SYM_ERR,
+
+	/* add new constants above here */
+	__ETHTOOL_A_STATS_ETH_PHY_CNT,
+	ETHTOOL_A_STATS_ETH_PHY_MAX = (__ETHTOOL_A_STATS_ETH_PHY_CNT - 1)
+};
+
 /* generic netlink info */
 #define ETHTOOL_GENL_NAME "ethtool"
 #define ETHTOOL_GENL_VERSION 1