[PATCH v2 3/4] net: Let the active time stamping layer be selectable.
From: Köry Maincent
Date: Fri Mar 03 2023 - 11:43:37 EST
From: Richard Cochran <richardcochran@xxxxxxxxx>
Make the sysfs knob writable, and add checks in the ioctl and time
stamping paths to respect the currently selected time stamping layer.
Signed-off-by: Richard Cochran <richardcochran@xxxxxxxxx>
Signed-off-by: Kory Maincent <kory.maincent@xxxxxxxxxxx>
---
Notes:
Changes in v2:
- Move selected_timestamping_layer introduction in this patch.
- Replace strmcmp by sysfs_streq.
- Use the PHY timestamp only if available.
.../ABI/testing/sysfs-class-net-timestamping | 5 +-
drivers/net/phy/phy_device.c | 6 +++
include/linux/netdevice.h | 10 ++++
net/core/dev_ioctl.c | 44 ++++++++++++++--
net/core/net-sysfs.c | 50 +++++++++++++++++--
net/core/timestamping.c | 6 +++
net/ethtool/common.c | 18 +++++--
7 files changed, 127 insertions(+), 12 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-class-net-timestamping b/Documentation/ABI/testing/sysfs-class-net-timestamping
index 529c3a6eb607..6dfd59740cad 100644
--- a/Documentation/ABI/testing/sysfs-class-net-timestamping
+++ b/Documentation/ABI/testing/sysfs-class-net-timestamping
@@ -11,7 +11,10 @@ What: /sys/class/net/<iface>/current_timestamping_provider
Date: January 2022
Contact: Richard Cochran <richardcochran@xxxxxxxxx>
Description:
- Show the current SO_TIMESTAMPING provider.
+ Shows or sets the current SO_TIMESTAMPING provider.
+ When changing the value, some packets in the kernel
+ networking stack may still be delivered with time
+ stamps from the previous provider.
The possible values are:
- "mac" The MAC provides time stamping.
- "phy" The PHY or MII device provides time stamping.
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 8cff61dbc4b5..8dff0c6493b5 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1451,6 +1451,11 @@ int phy_attach_direct(struct net_device *dev, struct phy_device *phydev,
phydev->phy_link_change = phy_link_change;
if (dev) {
+ if (phy_has_hwtstamp(phydev))
+ dev->selected_timestamping_layer = PHY_TIMESTAMPING;
+ else
+ dev->selected_timestamping_layer = MAC_TIMESTAMPING;
+
phydev->attached_dev = dev;
dev->phydev = phydev;
@@ -1762,6 +1767,7 @@ void phy_detach(struct phy_device *phydev)
phy_suspend(phydev);
if (dev) {
+ dev->selected_timestamping_layer = MAC_TIMESTAMPING;
phydev->attached_dev->phydev = NULL;
phydev->attached_dev = NULL;
}
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index ba2bd604359d..d8e9da2526f0 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1742,6 +1742,11 @@ enum netdev_ml_priv_type {
ML_PRIV_CAN,
};
+enum timestamping_layer {
+ MAC_TIMESTAMPING,
+ PHY_TIMESTAMPING,
+};
+
/**
* struct net_device - The DEVICE structure.
*
@@ -1981,6 +1986,9 @@ enum netdev_ml_priv_type {
*
* @threaded: napi threaded mode is enabled
*
+ * @selected_timestamping_layer: Tracks whether the MAC or the PHY
+ * performs packet time stamping.
+ *
* @net_notifier_list: List of per-net netdev notifier block
* that follow this device when it is moved
* to another network namespace.
@@ -2339,6 +2347,8 @@ struct net_device {
unsigned wol_enabled:1;
unsigned threaded:1;
+ enum timestamping_layer selected_timestamping_layer;
+
struct list_head net_notifier_list;
#if IS_ENABLED(CONFIG_MACSEC)
diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c
index 7674bb9f3076..cc7cf2a542fb 100644
--- a/net/core/dev_ioctl.c
+++ b/net/core/dev_ioctl.c
@@ -262,6 +262,43 @@ static int dev_eth_ioctl(struct net_device *dev,
return err;
}
+static int dev_hwtstamp_ioctl(struct net_device *dev,
+ struct ifreq *ifr, unsigned int cmd)
+{
+ const struct net_device_ops *ops = dev->netdev_ops;
+ int err;
+
+ err = dsa_ndo_eth_ioctl(dev, ifr, cmd);
+ if (err == 0 || err != -EOPNOTSUPP)
+ return err;
+
+ if (!netif_device_present(dev))
+ return -ENODEV;
+
+ switch (dev->selected_timestamping_layer) {
+
+ case MAC_TIMESTAMPING:
+ if (ops->ndo_do_ioctl == phy_do_ioctl) {
+ /* Some drivers set .ndo_do_ioctl to phy_do_ioctl. */
+ err = -EOPNOTSUPP;
+ } else {
+ err = ops->ndo_eth_ioctl(dev, ifr, cmd);
+ }
+ break;
+
+ case PHY_TIMESTAMPING:
+ if (phy_has_hwtstamp(dev->phydev)) {
+ err = phy_mii_ioctl(dev->phydev, ifr, cmd);
+ } else {
+ err = -ENODEV;
+ WARN_ON(1);
+ }
+ break;
+ }
+
+ return err;
+}
+
static int dev_siocbond(struct net_device *dev,
struct ifreq *ifr, unsigned int cmd)
{
@@ -397,6 +434,9 @@ static int dev_ifsioc(struct net *net, struct ifreq *ifr, void __user *data,
return err;
fallthrough;
+ case SIOCGHWTSTAMP:
+ return dev_hwtstamp_ioctl(dev, ifr, cmd);
+
/*
* Unknown or private ioctl
*/
@@ -407,9 +447,7 @@ static int dev_ifsioc(struct net *net, struct ifreq *ifr, void __user *data,
if (cmd == SIOCGMIIPHY ||
cmd == SIOCGMIIREG ||
- cmd == SIOCSMIIREG ||
- cmd == SIOCSHWTSTAMP ||
- cmd == SIOCGHWTSTAMP) {
+ cmd == SIOCSMIIREG) {
err = dev_eth_ioctl(dev, ifr, cmd);
} else if (cmd == SIOCBONDENSLAVE ||
cmd == SIOCBONDRELEASE ||
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index 26095634fb31..66079424b100 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -666,17 +666,59 @@ static ssize_t current_timestamping_provider_show(struct device *dev,
if (!rtnl_trylock())
return restart_syscall();
- if (phy_has_tsinfo(phydev)) {
- ret = sprintf(buf, "%s\n", "phy");
- } else {
+ switch (netdev->selected_timestamping_layer) {
+ case MAC_TIMESTAMPING:
ret = sprintf(buf, "%s\n", "mac");
+ break;
+ case PHY_TIMESTAMPING:
+ ret = sprintf(buf, "%s\n", "phy");
+ break;
}
rtnl_unlock();
return ret;
}
-static DEVICE_ATTR_RO(current_timestamping_provider);
+
+static ssize_t current_timestamping_provider_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct net_device *netdev = to_net_dev(dev);
+ struct net *net = dev_net(netdev);
+ enum timestamping_layer flavor;
+
+ if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
+ return -EPERM;
+
+ if (sysfs_streq(buf, "mac"))
+ flavor = MAC_TIMESTAMPING;
+ else if (sysfs_streq(buf, "phy"))
+ flavor = PHY_TIMESTAMPING;
+ else
+ return -EINVAL;
+
+ if (!rtnl_trylock())
+ return restart_syscall();
+
+ if (!dev_isalive(netdev))
+ goto out;
+
+ if (netdev->selected_timestamping_layer != flavor) {
+ const struct net_device_ops *ops = netdev->netdev_ops;
+ struct ifreq ifr = {0};
+
+ /* Disable time stamping in the current layer. */
+ if (netif_device_present(netdev) && ops->ndo_eth_ioctl)
+ ops->ndo_eth_ioctl(netdev, &ifr, SIOCSHWTSTAMP);
+
+ netdev->selected_timestamping_layer = flavor;
+ }
+out:
+ rtnl_unlock();
+ return len;
+}
+static DEVICE_ATTR_RW(current_timestamping_provider);
static struct attribute *net_class_attrs[] __ro_after_init = {
&dev_attr_netdev_group.attr,
diff --git a/net/core/timestamping.c b/net/core/timestamping.c
index 04840697fe79..31c3142787b7 100644
--- a/net/core/timestamping.c
+++ b/net/core/timestamping.c
@@ -28,6 +28,9 @@ void skb_clone_tx_timestamp(struct sk_buff *skb)
if (!skb->sk)
return;
+ if (skb->dev->selected_timestamping_layer != PHY_TIMESTAMPING)
+ return;
+
type = classify(skb);
if (type == PTP_CLASS_NONE)
return;
@@ -50,6 +53,9 @@ bool skb_defer_rx_timestamp(struct sk_buff *skb)
if (!skb->dev || !skb->dev->phydev || !skb->dev->phydev->mii_ts)
return false;
+ if (skb->dev->selected_timestamping_layer != PHY_TIMESTAMPING)
+ return false;
+
if (skb_headroom(skb) < ETH_HLEN)
return false;
diff --git a/net/ethtool/common.c b/net/ethtool/common.c
index 64a7e05cf2c2..255170c9345a 100644
--- a/net/ethtool/common.c
+++ b/net/ethtool/common.c
@@ -548,10 +548,20 @@ int __ethtool_get_ts_info(struct net_device *dev, struct ethtool_ts_info *info)
memset(info, 0, sizeof(*info));
info->cmd = ETHTOOL_GET_TS_INFO;
- if (phy_has_tsinfo(phydev))
- return phy_ts_info(phydev, info);
- if (ops->get_ts_info)
- return ops->get_ts_info(dev, info);
+ switch (dev->selected_timestamping_layer) {
+
+ case MAC_TIMESTAMPING:
+ if (ops->get_ts_info)
+ return ops->get_ts_info(dev, info);
+ break;
+
+ case PHY_TIMESTAMPING:
+ if (phy_has_tsinfo(phydev)) {
+ return phy_ts_info(phydev, info);
+ }
+ WARN_ON(1);
+ return -ENODEV;
+ }
info->so_timestamping = SOF_TIMESTAMPING_RX_SOFTWARE |
SOF_TIMESTAMPING_SOFTWARE;
--
2.25.1