Merge branch 'improvements-over-dsa-conduit-ethtool-ops'

Vladimir Oltean says:

====================
Improvements over DSA conduit ethtool ops

DSA interceps 'ethtool -S eth0', where eth0 is the host port of the
switch (called 'conduit'). It does this because otherwise there is no
way to report port counters for the CPU port, which is a MAC like any
other of that switch, except Linux exposes no net_device for it, thus no
ethtool hook.

Having understood all downsides of this debugging interface, when we
need it we needed, so the proposed changes here are to make it more
useful by dumping more counters in it: not just the switch CPU port,
but all other switch ports in the tree which lack a net_device. Not
reinventing any wheel, just putting more output in an existing command.

That is patch 3/3. The other 2 are cleanup.
====================

Link: https://patch.msgid.link/20251122112311.138784-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 102 insertions, 43 deletions

diff --git a/net/dsa/conduit.c b/net/dsa/conduit.c
index 4ae255cfb23f..a1b044467bd6 100644
--- a/net/dsa/conduit.c
+++ b/net/dsa/conduit.c
@@ -26,7 +26,7 @@ static int dsa_conduit_get_regs_len(struct net_device *dev)
 	int ret = 0;
 	int len;
 
-	if (ops->get_regs_len) {
+	if (ops && ops->get_regs_len) {
 		netdev_lock_ops(dev);
 		len = ops->get_regs_len(dev);
 		netdev_unlock_ops(dev);
@@ -59,7 +59,7 @@ static void dsa_conduit_get_regs(struct net_device *dev,
 	int port = cpu_dp->index;
 	int len;
 
-	if (ops->get_regs_len && ops->get_regs) {
+	if (ops && ops->get_regs_len && ops->get_regs) {
 		netdev_lock_ops(dev);
 		len = ops->get_regs_len(dev);
 		if (len < 0) {
@@ -87,30 +87,56 @@ static void dsa_conduit_get_regs(struct net_device *dev,
 	}
 }
 
+static ssize_t dsa_conduit_append_port_stats(struct dsa_switch *ds, int port,
+					     u64 *data, size_t start)
+{
+	int count;
+
+	if (!ds->ops->get_sset_count)
+		return 0;
+
+	count = ds->ops->get_sset_count(ds, port, ETH_SS_STATS);
+	if (count < 0)
+		return count;
+
+	if (ds->ops->get_ethtool_stats)
+		ds->ops->get_ethtool_stats(ds, port, data + start);
+
+	return count;
+}
+
 static void dsa_conduit_get_ethtool_stats(struct net_device *dev,
 					  struct ethtool_stats *stats,
-					  uint64_t *data)
+					  u64 *data)
 {
-	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	struct dsa_port *dp, *cpu_dp = dev->dsa_ptr;
 	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
-	struct dsa_switch *ds = cpu_dp->ds;
-	int port = cpu_dp->index;
-	int count = 0;
+	struct dsa_switch_tree *dst = cpu_dp->dst;
+	int count, mcount = 0;
 
-	if (ops->get_sset_count && ops->get_ethtool_stats) {
+	if (ops && ops->get_sset_count && ops->get_ethtool_stats) {
 		netdev_lock_ops(dev);
-		count = ops->get_sset_count(dev, ETH_SS_STATS);
+		mcount = ops->get_sset_count(dev, ETH_SS_STATS);
 		ops->get_ethtool_stats(dev, stats, data);
 		netdev_unlock_ops(dev);
 	}
 
-	if (ds->ops->get_ethtool_stats)
-		ds->ops->get_ethtool_stats(ds, port, data + count);
+	list_for_each_entry(dp, &dst->ports, list) {
+		if (!dsa_port_is_dsa(dp) && !dsa_port_is_cpu(dp))
+			continue;
+
+		count = dsa_conduit_append_port_stats(dp->ds, dp->index,
+						      data, mcount);
+		if (count < 0)
+			return;
+
+		mcount += count;
+	}
 }
 
 static void dsa_conduit_get_ethtool_phy_stats(struct net_device *dev,
 					      struct ethtool_stats *stats,
-					      uint64_t *data)
+					      u64 *data)
 {
 	struct dsa_port *cpu_dp = dev->dsa_ptr;
 	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
@@ -118,11 +144,11 @@ static void dsa_conduit_get_ethtool_phy_stats(struct net_device *dev,
 	int port = cpu_dp->index;
 	int count = 0;
 
-	if (dev->phydev && !ops->get_ethtool_phy_stats) {
+	if (dev->phydev && (!ops || !ops->get_ethtool_phy_stats)) {
 		count = phy_ethtool_get_sset_count(dev->phydev);
 		if (count >= 0)
 			phy_ethtool_get_stats(dev->phydev, stats, data);
-	} else if (ops->get_sset_count && ops->get_ethtool_phy_stats) {
+	} else if (ops && ops->get_sset_count && ops->get_ethtool_phy_stats) {
 		netdev_lock_ops(dev);
 		count = ops->get_sset_count(dev, ETH_SS_PHY_STATS);
 		ops->get_ethtool_phy_stats(dev, stats, data);
@@ -136,45 +162,82 @@ static void dsa_conduit_get_ethtool_phy_stats(struct net_device *dev,
 		ds->ops->get_ethtool_phy_stats(ds, port, data + count);
 }
 
+static void dsa_conduit_append_port_sset_count(struct dsa_switch *ds, int port,
+					       int sset, int *count)
+{
+	if (ds->ops->get_sset_count)
+		*count += ds->ops->get_sset_count(ds, port, sset);
+}
+
 static int dsa_conduit_get_sset_count(struct net_device *dev, int sset)
 {
-	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	struct dsa_port *dp, *cpu_dp = dev->dsa_ptr;
 	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
-	struct dsa_switch *ds = cpu_dp->ds;
+	struct dsa_switch_tree *dst = cpu_dp->dst;
 	int count = 0;
 
 	netdev_lock_ops(dev);
 	if (sset == ETH_SS_PHY_STATS && dev->phydev &&
-	    !ops->get_ethtool_phy_stats)
+	    (!ops || !ops->get_ethtool_phy_stats))
 		count = phy_ethtool_get_sset_count(dev->phydev);
-	else if (ops->get_sset_count)
+	else if (ops && ops->get_sset_count)
 		count = ops->get_sset_count(dev, sset);
 	netdev_unlock_ops(dev);
 
 	if (count < 0)
 		count = 0;
 
-	if (ds->ops->get_sset_count)
-		count += ds->ops->get_sset_count(ds, cpu_dp->index, sset);
+	list_for_each_entry(dp, &dst->ports, list) {
+		if (!dsa_port_is_dsa(dp) && !dsa_port_is_cpu(dp))
+			continue;
+
+		dsa_conduit_append_port_sset_count(dp->ds, dp->index, sset,
+						   &count);
+	}
 
 	return count;
 }
 
-static void dsa_conduit_get_strings(struct net_device *dev, uint32_t stringset,
-				    uint8_t *data)
+static ssize_t dsa_conduit_append_port_strings(struct dsa_switch *ds, int port,
+					       u32 stringset, u8 *data,
+					       size_t start)
 {
-	struct dsa_port *cpu_dp = dev->dsa_ptr;
-	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
-	struct dsa_switch *ds = cpu_dp->ds;
-	int port = cpu_dp->index;
 	int len = ETH_GSTRING_LEN;
-	int mcount = 0, count, i;
-	uint8_t pfx[4];
-	uint8_t *ndata;
+	u8 pfx[8], *ndata;
+	int count, i;
+
+	if (!ds->ops->get_strings)
+		return 0;
 
-	snprintf(pfx, sizeof(pfx), "p%.2d", port);
+	snprintf(pfx, sizeof(pfx), "s%.2d_p%.2d", ds->index, port);
 	/* We do not want to be NULL-terminated, since this is a prefix */
 	pfx[sizeof(pfx) - 1] = '_';
+	ndata = data + start * len;
+	/* This function copies ETH_GSTRINGS_LEN bytes, we will mangle
+	 * the output after to prepend our CPU port prefix we
+	 * constructed earlier
+	 */
+	ds->ops->get_strings(ds, port, stringset, ndata);
+	count = ds->ops->get_sset_count(ds, port, stringset);
+	if (count < 0)
+		return count;
+
+	for (i = 0; i < count; i++) {
+		memmove(ndata + (i * len + sizeof(pfx)),
+			ndata + i * len, len - sizeof(pfx));
+		memcpy(ndata + i * len, pfx, sizeof(pfx));
+	}
+
+	return count;
+}
+
+static void dsa_conduit_get_strings(struct net_device *dev, u32 stringset,
+				    u8 *data)
+{
+	struct dsa_port *dp, *cpu_dp = dev->dsa_ptr;
+	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
+	struct dsa_switch_tree *dst = cpu_dp->dst;
+	int count, mcount = 0;
 
 	netdev_lock_ops(dev);
 	if (stringset == ETH_SS_PHY_STATS && dev->phydev &&
@@ -192,21 +255,17 @@ static void dsa_conduit_get_strings(struct net_device *dev, uint32_t stringset,
 	}
 	netdev_unlock_ops(dev);
 
-	if (ds->ops->get_strings) {
-		ndata = data + mcount * len;
-		/* This function copies ETH_GSTRINGS_LEN bytes, we will mangle
-		 * the output after to prepend our CPU port prefix we
-		 * constructed earlier
-		 */
-		ds->ops->get_strings(ds, port, stringset, ndata);
-		count = ds->ops->get_sset_count(ds, port, stringset);
+	list_for_each_entry(dp, &dst->ports, list) {
+		if (!dsa_port_is_dsa(dp) && !dsa_port_is_cpu(dp))
+			continue;
+
+		count = dsa_conduit_append_port_strings(dp->ds, dp->index,
+							stringset, data,
+							mcount);
 		if (count < 0)
 			return;
-		for (i = 0; i < count; i++) {
-			memmove(ndata + (i * len + sizeof(pfx)),
-				ndata + i * len, len - sizeof(pfx));
-			memcpy(ndata + i * len, pfx, sizeof(pfx));
-		}
+
+		mcount += count;
 	}
 }