[PATCHv4 net-next 1/3] ethtool: Add phy statistics

[Andrew Lunn <andrew@lunn.ch>]

Ethernet PHYs can maintain statistics, for example errors while idle
and receive errors. Add an ethtool mechanism to retrieve these
statistics, using the same model as MAC statistics.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
---
 include/linux/phy.h          |  6 ++++
 include/uapi/linux/ethtool.h |  3 ++
 net/core/ethtool.c           | 81 +++++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 89 insertions(+), 1 deletion(-)

diff --git a/include/linux/phy.h b/include/linux/phy.h
index 05fde31b6dc6..a89cb0eef911 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -589,6 +589,12 @@ struct phy_driver {
 	int (*module_eeprom)(struct phy_device *dev,
 			     struct ethtool_eeprom *ee, u8 *data);
 
+	/* Get statistics from the phy using ethtool */
+	int (*get_sset_count)(struct phy_device *dev);
+	void (*get_strings)(struct phy_device *dev, u8 *data);
+	void (*get_stats)(struct phy_device *dev,
+			  struct ethtool_stats *stats, u64 *data);
+
 	struct device_driver driver;
 };
 #define to_phy_driver(d) container_of(d, struct phy_driver, driver)
diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index cd1629170103..57fa39005e79 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -542,6 +542,7 @@ struct ethtool_pauseparam {
  *	now deprecated
  * @ETH_SS_FEATURES: Device feature names
  * @ETH_SS_RSS_HASH_FUNCS: RSS hush function names
+ * @ETH_SS_PHY_STATS: Statistic names, for use with %ETHTOOL_GPHYSTATS
  */
 enum ethtool_stringset {
 	ETH_SS_TEST		= 0,
@@ -551,6 +552,7 @@ enum ethtool_stringset {
 	ETH_SS_FEATURES,
 	ETH_SS_RSS_HASH_FUNCS,
 	ETH_SS_TUNABLES,
+	ETH_SS_PHY_STATS,
 };
 
 /**
@@ -1225,6 +1227,7 @@ enum ethtool_sfeatures_retval_bits {
 #define ETHTOOL_SRSSH		0x00000047 /* Set RX flow hash configuration */
 #define ETHTOOL_GTUNABLE	0x00000048 /* Get tunable configuration */
 #define ETHTOOL_STUNABLE	0x00000049 /* Set tunable configuration */
+#define ETHTOOL_GPHYSTATS	0x0000004a /* get PHY-specific statistics */
 
 /* compatibility with older code */
 #define SPARC_ETH_GSET		ETHTOOL_GSET
diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index 09948a726347..daf04709dd3c 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -191,6 +191,23 @@ static int ethtool_set_features(struct net_device *dev, void __user *useraddr)
 	return ret;
 }
 
+static int phy_get_sset_count(struct phy_device *phydev)
+{
+	int ret;
+
+	if (phydev->drv->get_sset_count &&
+	    phydev->drv->get_strings &&
+	    phydev->drv->get_stats) {
+		mutex_lock(&phydev->lock);
+		ret = phydev->drv->get_sset_count(phydev);
+		mutex_unlock(&phydev->lock);
+
+		return ret;
+	}
+
+	return -EOPNOTSUPP;
+}
+
 static int __ethtool_get_sset_count(struct net_device *dev, int sset)
 {
 	const struct ethtool_ops *ops = dev->ethtool_ops;
@@ -204,6 +221,13 @@ static int __ethtool_get_sset_count(struct net_device *dev, int sset)
 	if (sset == ETH_SS_TUNABLES)
 		return ARRAY_SIZE(tunable_strings);
 
+	if (sset == ETH_SS_PHY_STATS) {
+		if (dev->phydev)
+			return phy_get_sset_count(dev->phydev);
+		else
+			return -EOPNOTSUPP;
+	}
+
 	if (ops->get_sset_count && ops->get_strings)
 		return ops->get_sset_count(dev, sset);
 	else
@@ -223,7 +247,17 @@ static void __ethtool_get_strings(struct net_device *dev,
 		       sizeof(rss_hash_func_strings));
 	else if (stringset == ETH_SS_TUNABLES)
 		memcpy(data, tunable_strings, sizeof(tunable_strings));
-	else
+	else if (stringset == ETH_SS_PHY_STATS) {
+		struct phy_device *phydev = dev->phydev;
+
+		if (phydev) {
+			mutex_lock(&phydev->lock);
+			phydev->drv->get_strings(phydev, data);
+			mutex_unlock(&phydev->lock);
+		} else {
+			return;
+		}
+	} else
 		/* ops->get_strings is valid because checked earlier */
 		ops->get_strings(dev, stringset, data);
 }
@@ -1401,6 +1435,47 @@ static int ethtool_get_stats(struct net_device *dev, void __user *useraddr)
 	return ret;
 }
 
+static int ethtool_get_phy_stats(struct net_device *dev, void __user *useraddr)
+{
+	struct ethtool_stats stats;
+	struct phy_device *phydev = dev->phydev;
+	u64 *data;
+	int ret, n_stats;
+
+	if (!phydev)
+		return -EOPNOTSUPP;
+
+	n_stats = phy_get_sset_count(phydev);
+
+	if (n_stats < 0)
+		return n_stats;
+	WARN_ON(n_stats == 0);
+
+	if (copy_from_user(&stats, useraddr, sizeof(stats)))
+		return -EFAULT;
+
+	stats.n_stats = n_stats;
+	data = kmalloc_array(n_stats, sizeof(u64), GFP_USER);
+	if (!data)
+		return -ENOMEM;
+
+	mutex_lock(&phydev->lock);
+	phydev->drv->get_stats(phydev, &stats, data);
+	mutex_unlock(&phydev->lock);
+
+	ret = -EFAULT;
+	if (copy_to_user(useraddr, &stats, sizeof(stats)))
+		goto out;
+	useraddr += sizeof(stats);
+	if (copy_to_user(useraddr, data, stats.n_stats * sizeof(u64)))
+		goto out;
+	ret = 0;
+
+ out:
+	kfree(data);
+	return ret;
+}
+
 static int ethtool_get_perm_addr(struct net_device *dev, void __user *useraddr)
 {
 	struct ethtool_perm_addr epaddr;
@@ -1779,6 +1854,7 @@ int dev_ethtool(struct net *net, struct ifreq *ifr)
 	case ETHTOOL_GSSET_INFO:
 	case ETHTOOL_GSTRINGS:
 	case ETHTOOL_GSTATS:
+	case ETHTOOL_GPHYSTATS:
 	case ETHTOOL_GTSO:
 	case ETHTOOL_GPERMADDR:
 	case ETHTOOL_GUFO:
@@ -1991,6 +2067,9 @@ int dev_ethtool(struct net *net, struct ifreq *ifr)
 	case ETHTOOL_STUNABLE:
 		rc = ethtool_set_tunable(dev, useraddr);
 		break;
+	case ETHTOOL_GPHYSTATS:
+		rc = ethtool_get_phy_stats(dev, useraddr);
+		break;
 	default:
 		rc = -EOPNOTSUPP;
 	}
-- 
2.6.4