Subject: [RFC PATCH net-next v6 4/5] bond: Add ndo_hwtstamp_get/set support to bond driver

From: Maxim Georgiev <[email-masked]>
Date: Mon, 1 May 2023 22:31:49 -0600

This patch changes bonding net driver to use the newly
introduced ndo_hwtstamp_get/set API to pass hw timestamp
requests to underlying NIC drivers in case if these drivers
implement ndo_hwtstamp_get/set functions. Otherwise Bonding
subsystem falls back to calling ndo_eth_ioctl.

Suggested-by: Vladimir Oltean <[email-masked]>
Signed-off-by: Maxim Georgiev <[email-masked]>
---
Notes:
  Changes in v6:
  - Patch title was updated. No code changes.
---
 drivers/net/bonding/bond_main.c | 106 ++++++++++++++++++++------------
 1 file changed, 66 insertions(+), 40 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 710548dbd0c1..21969afff2a9 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -4408,11 +4408,6 @@ static int bond_eth_ioctl(struct net_device *bond_dev, struct ifreq *ifr, int cm
 {
 	struct bonding *bond = netdev_priv(bond_dev);
 	struct mii_ioctl_data *mii = NULL;
-	const struct net_device_ops *ops;
-	struct net_device *real_dev;
-	struct hwtstamp_config cfg;
-	struct ifreq ifrr;
-	int res = 0;
 
 	netdev_dbg(bond_dev, "bond_eth_ioctl: cmd=%d\n", cmd);
 
@@ -4439,44 +4434,11 @@ static int bond_eth_ioctl(struct net_device *bond_dev, struct ifreq *ifr, int cm
 		}
 
 		break;
-	case SIOCSHWTSTAMP:
-		if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
-			return -EFAULT;
-
-		if (!(cfg.flags & HWTSTAMP_FLAG_BONDED_PHC_INDEX))
-			return -EOPNOTSUPP;
-
-		fallthrough;
-	case SIOCGHWTSTAMP:
-		real_dev = bond_option_active_slave_get_rcu(bond);
-		if (!real_dev)
-			return -EOPNOTSUPP;
-
-		strscpy_pad(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
-		ifrr.ifr_ifru = ifr->ifr_ifru;
-
-		ops = real_dev->netdev_ops;
-		if (netif_device_present(real_dev) && ops->ndo_eth_ioctl) {
-			res = ops->ndo_eth_ioctl(real_dev, &ifrr, cmd);
-			if (res)
-				return res;
-
-			ifr->ifr_ifru = ifrr.ifr_ifru;
-			if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
-				return -EFAULT;
-
-			/* Set the BOND_PHC_INDEX flag to notify user space */
-			cfg.flags |= HWTSTAMP_FLAG_BONDED_PHC_INDEX;
-
-			return copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg)) ?
-				-EFAULT : 0;
-		}
-		fallthrough;
 	default:
-		res = -EOPNOTSUPP;
+		return -EOPNOTSUPP;
 	}
 
-	return res;
+	return 0;
 }
 
 static int bond_do_ioctl(struct net_device *bond_dev, struct ifreq *ifr, int cmd)
@@ -5650,6 +5612,68 @@ static u32 bond_mode_bcast_speed(struct slave *slave, u32 speed)
 	return speed;
 }
 
+static int bond_set_phc_index_flag(struct kernel_hwtstamp_config *kernel_cfg)
+{
+	struct ifreq *ifr = kernel_cfg->ifr;
+	struct hwtstamp_config cfg;
+
+	if (kernel_cfg->kernel_flags & KERNEL_HWTSTAMP_FLAG_IFR_RESULT) {
+		if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
+			return -EFAULT;
+
+		cfg.flags |= HWTSTAMP_FLAG_BONDED_PHC_INDEX;
+		if (copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg)))
+			return -EFAULT;
+	} else {
+		kernel_cfg->flags |= HWTSTAMP_FLAG_BONDED_PHC_INDEX;
+	}
+
+	return 0;
+}
+
+static int bond_hwtstamp_get(struct net_device *dev,
+			     struct kernel_hwtstamp_config *cfg,
+			     struct netlink_ext_ack *extack)
+{
+	struct bonding *bond = netdev_priv(dev);
+	struct net_device *real_dev;
+	int err;
+
+	real_dev = bond_option_active_slave_get_rcu(bond);
+	if (!real_dev)
+		return -EOPNOTSUPP;
+
+	err = generic_hwtstamp_get_lower(real_dev, cfg, extack);
+	if (err)
+		return err;
+
+	/* Set the BOND_PHC_INDEX flag to notify user space */
+	return bond_set_phc_index_flag(cfg);
+}
+
+static int bond_hwtstamp_set(struct net_device *dev,
+			     struct kernel_hwtstamp_config *kernel_cfg,
+			     struct netlink_ext_ack *extack)
+{
+	struct bonding *bond = netdev_priv(dev);
+	struct net_device *real_dev;
+	int err;
+
+	if (!(kernel_cfg->flags & HWTSTAMP_FLAG_BONDED_PHC_INDEX))
+		return -EOPNOTSUPP;
+
+	real_dev = bond_option_active_slave_get_rcu(bond);
+	if (!real_dev)
+		return -EOPNOTSUPP;
+
+	err = generic_hwtstamp_set_lower(real_dev, kernel_cfg, extack);
+	if (err)
+		return err;
+
+	/* Set the BOND_PHC_INDEX flag to notify user space */
+	return bond_set_phc_index_flag(kernel_cfg);
+}
+
 static int bond_ethtool_get_link_ksettings(struct net_device *bond_dev,
 					   struct ethtool_link_ksettings *cmd)
 {
@@ -5798,6 +5822,8 @@ static const struct net_device_ops bond_netdev_ops = {
 	.ndo_bpf		= bond_xdp,
 	.ndo_xdp_xmit           = bond_xdp_xmit,
 	.ndo_xdp_get_xmit_slave = bond_xdp_get_xmit_slave,
+	.ndo_hwtstamp_get	= bond_hwtstamp_get,
+	.ndo_hwtstamp_set	= bond_hwtstamp_set,
 };
 
 static const struct device_type bond_type = {
-- 
2.40.1