1 files changed, 83 insertions, 8 deletions

diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c
index d0223ecd6f6f..72e077022348 100644
--- a/net/core/dev_ioctl.c
+++ b/net/core/dev_ioctl.c
@@ -5,6 +5,7 @@
 #include <linux/etherdevice.h>
 #include <linux/rtnetlink.h>
 #include <linux/net_tstamp.h>
+#include <linux/phylib_stubs.h>
 #include <linux/wireless.h>
 #include <linux/if_bridge.h>
 #include <net/dsa_stubs.h>
@@ -252,6 +253,30 @@ static int dev_eth_ioctl(struct net_device *dev,
 	return ops->ndo_eth_ioctl(dev, ifr, cmd);
 }
 
+/**
+ * dev_get_hwtstamp_phylib() - Get hardware timestamping settings of NIC
+ *	or of attached phylib PHY
+ * @dev: Network device
+ * @cfg: Timestamping configuration structure
+ *
+ * Helper for enforcing a common policy that phylib timestamping, if available,
+ * should take precedence in front of hardware timestamping provided by the
+ * netdev.
+ *
+ * Note: phy_mii_ioctl() only handles SIOCSHWTSTAMP (not SIOCGHWTSTAMP), and
+ * there only exists a phydev->mii_ts->hwtstamp() method. So this will return
+ * -EOPNOTSUPP for phylib for now, which is still more accurate than letting
+ * the netdev handle the GET request.
+ */
+static int dev_get_hwtstamp_phylib(struct net_device *dev,
+				   struct kernel_hwtstamp_config *cfg)
+{
+	if (phy_has_hwtstamp(dev->phydev))
+		return phy_hwtstamp_get(dev->phydev, cfg);
+
+	return dev->netdev_ops->ndo_hwtstamp_get(dev, cfg);
+}
+
 static int dev_get_hwtstamp(struct net_device *dev, struct ifreq *ifr)
 {
 	const struct net_device_ops *ops = dev->netdev_ops;
@@ -266,7 +291,7 @@ static int dev_get_hwtstamp(struct net_device *dev, struct ifreq *ifr)
 		return -ENODEV;
 
 	kernel_cfg.ifr = ifr;
-	err = ops->ndo_hwtstamp_get(dev, &kernel_cfg);
+	err = dev_get_hwtstamp_phylib(dev, &kernel_cfg);
 	if (err)
 		return err;
 
@@ -283,6 +308,59 @@ static int dev_get_hwtstamp(struct net_device *dev, struct ifreq *ifr)
 	return 0;
 }
 
+/**
+ * dev_set_hwtstamp_phylib() - Change hardware timestamping of NIC
+ *	or of attached phylib PHY
+ * @dev: Network device
+ * @cfg: Timestamping configuration structure
+ * @extack: Netlink extended ack message structure, for error reporting
+ *
+ * Helper for enforcing a common policy that phylib timestamping, if available,
+ * should take precedence in front of hardware timestamping provided by the
+ * netdev. If the netdev driver needs to perform specific actions even for PHY
+ * timestamping to work properly (a switch port must trap the timestamped
+ * frames and not forward them), it must set IFF_SEE_ALL_HWTSTAMP_REQUESTS in
+ * dev->priv_flags.
+ */
+static int dev_set_hwtstamp_phylib(struct net_device *dev,
+				   struct kernel_hwtstamp_config *cfg,
+				   struct netlink_ext_ack *extack)
+{
+	const struct net_device_ops *ops = dev->netdev_ops;
+	bool phy_ts = phy_has_hwtstamp(dev->phydev);
+	struct kernel_hwtstamp_config old_cfg = {};
+	bool changed = false;
+	int err;
+
+	cfg->source = phy_ts ? HWTSTAMP_SOURCE_PHYLIB : HWTSTAMP_SOURCE_NETDEV;
+
+	if (!phy_ts || (dev->priv_flags & IFF_SEE_ALL_HWTSTAMP_REQUESTS)) {
+		err = ops->ndo_hwtstamp_get(dev, &old_cfg);
+		if (err)
+			return err;
+
+		err = ops->ndo_hwtstamp_set(dev, cfg, extack);
+		if (err) {
+			if (extack->_msg)
+				netdev_err(dev, "%s\n", extack->_msg);
+			return err;
+		}
+
+		changed = kernel_hwtstamp_config_changed(&old_cfg, cfg);
+	}
+
+	if (phy_ts) {
+		err = phy_hwtstamp_set(dev->phydev, cfg, extack);
+		if (err) {
+			if (changed)
+				ops->ndo_hwtstamp_set(dev, &old_cfg, NULL);
+			return err;
+		}
+	}
+
+	return 0;
+}
+
 static int dev_set_hwtstamp(struct net_device *dev, struct ifreq *ifr)
 {
 	const struct net_device_ops *ops = dev->netdev_ops;
@@ -314,12 +392,9 @@ static int dev_set_hwtstamp(struct net_device *dev, struct ifreq *ifr)
 	if (!netif_device_present(dev))
 		return -ENODEV;
 
-	err = ops->ndo_hwtstamp_set(dev, &kernel_cfg, &extack);
-	if (err) {
-		if (extack._msg)
-			netdev_err(dev, "%s\n", extack._msg);
+	err = dev_set_hwtstamp_phylib(dev, &kernel_cfg, &extack);
+	if (err)
 		return err;
-	}
 
 	/* The driver may have modified the configuration, so copy the
 	 * updated version of it back to user space
@@ -362,7 +437,7 @@ int generic_hwtstamp_get_lower(struct net_device *dev,
 		return -ENODEV;
 
 	if (ops->ndo_hwtstamp_get)
-		return ops->ndo_hwtstamp_get(dev, kernel_cfg);
+		return dev_get_hwtstamp_phylib(dev, kernel_cfg);
 
 	/* Legacy path: unconverted lower driver */
 	return generic_hwtstamp_ioctl_lower(dev, SIOCGHWTSTAMP, kernel_cfg);
@@ -379,7 +454,7 @@ int generic_hwtstamp_set_lower(struct net_device *dev,
 		return -ENODEV;
 
 	if (ops->ndo_hwtstamp_set)
-		return ops->ndo_hwtstamp_set(dev, kernel_cfg, extack);
+		return dev_set_hwtstamp_phylib(dev, kernel_cfg, extack);
 
 	/* Legacy path: unconverted lower driver */
 	return generic_hwtstamp_ioctl_lower(dev, SIOCSHWTSTAMP, kernel_cfg);