[RFC PATCH net-next v6 2/5] net: Add ifreq pointer field to kernel_hwtstamp_config structure
From: Maxim Georgiev <hidden>
Date: 2023-05-02 04:32:05
Subsystem:
networking drivers, networking [general], socket timestamping, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Willem de Bruijn, Linus Torvalds
Considering the stackable nature of drivers there will be situations
where a driver implementing ndo_hwtstamp_get/set functions will have
to translate requests back to SIOCGHWTSTAMP/SIOCSHWTSTAMP IOCTLs
to pass them to lower level drivers that do not provide
ndo_hwtstamp_get/set callbacks. To simplify request translation in
such scenarios let's include a pointer to the original struct ifreq
to kernel_hwtstamp_config structure.
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Maxim Georgiev <redacted>
Notes:
Changes in v6:
- Patch title was updated. No code changes.
Changes in v5:
- kernel_hwtstamp_config kdoc is updated with the new field
descriptions.
Changes in V4:
- Introducing KERNEL_HWTSTAMP_FLAG_IFR_RESULT flag indicating that
the operation results are returned in the ifr referred by
struct kernel_hwtstamp_config instead of kernel_hwtstamp_config
glags/tx_type/rx_filter fields.
- Implementing generic_hwtstamp_set/set_lower() functions
which will be used by vlan, maxvlan, bond and potentially
other drivers translating ndo_hwtstamp_set/set calls to
lower level drivers.
---
include/linux/net_tstamp.h | 9 +++++
include/linux/netdevice.h | 6 +++
net/core/dev_ioctl.c | 80 +++++++++++++++++++++++++++++++++++---
3 files changed, 89 insertions(+), 6 deletions(-)
diff --git a/include/linux/net_tstamp.h b/include/linux/net_tstamp.h
index 7c59824f43f5..91d2738bf0a0 100644
--- a/include/linux/net_tstamp.h
+++ b/include/linux/net_tstamp.h@@ -11,6 +11,8 @@ * @flags: see struct hwtstamp_config * @tx_type: see struct hwtstamp_config * @rx_filter: see struct hwtstamp_config + * @ifr: pointer to ifreq structure from the original IOCTL request + * @kernel_flags: possible flags defined by kernel_hwtstamp_flags below * * Prefer using this structure for in-kernel processing of hardware * timestamping configuration, over the inextensible struct hwtstamp_config
@@ -20,6 +22,13 @@ struct kernel_hwtstamp_config { int flags; int tx_type; int rx_filter; + struct ifreq *ifr; + int kernel_flags; +}; + +/* possible values for kernel_hwtstamp_config->kernel_flags */ +enum kernel_hwtstamp_flags { + KERNEL_HWTSTAMP_FLAG_IFR_RESULT = BIT(0), }; static inline void hwtstamp_config_to_kernel(struct kernel_hwtstamp_config *kernel_cfg,
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 7160135ca540..42e96b12fd21 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h@@ -3942,6 +3942,12 @@ int put_user_ifreq(struct ifreq *ifr, void __user *arg); int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr, void __user *data, bool *need_copyout); int dev_ifconf(struct net *net, struct ifconf __user *ifc); +int generic_hwtstamp_set_lower(struct net_device *dev, + struct kernel_hwtstamp_config *kernel_cfg, + struct netlink_ext_ack *extack); +int generic_hwtstamp_get_lower(struct net_device *dev, + struct kernel_hwtstamp_config *kernel_cfg, + struct netlink_ext_ack *extack); int dev_ethtool(struct net *net, struct ifreq *ifr, void __user *userdata); unsigned int dev_get_flags(const struct net_device *); int __dev_change_flags(struct net_device *dev, unsigned int flags,
diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c
index a157b9ab5237..da1d2391822f 100644
--- a/net/core/dev_ioctl.c
+++ b/net/core/dev_ioctl.c@@ -265,14 +265,17 @@ static int dev_get_hwtstamp(struct net_device *dev, struct ifreq *ifr) if (!netif_device_present(dev)) return -ENODEV; + kernel_cfg.ifr = ifr; err = ops->ndo_hwtstamp_get(dev, &kernel_cfg, NULL); if (err) return err; - hwtstamp_config_from_kernel(&config, &kernel_cfg); + if (!(kernel_cfg.kernel_flags & KERNEL_HWTSTAMP_FLAG_IFR_RESULT)) { + hwtstamp_config_from_kernel(&config, &kernel_cfg); - if (copy_to_user(ifr->ifr_data, &config, sizeof(config))) - return -EFAULT; + if (copy_to_user(ifr->ifr_data, &config, sizeof(config))) + return -EFAULT; + } return 0; }
@@ -289,6 +292,7 @@ static int dev_set_hwtstamp(struct net_device *dev, struct ifreq *ifr) return -EFAULT; hwtstamp_config_to_kernel(&kernel_cfg, &cfg); + kernel_cfg.ifr = ifr; err = net_hwtstamp_validate(&kernel_cfg); if (err)
@@ -311,14 +315,78 @@ static int dev_set_hwtstamp(struct net_device *dev, struct ifreq *ifr) if (err) return err; - hwtstamp_config_from_kernel(&cfg, &kernel_cfg); + if (!(kernel_cfg.kernel_flags & KERNEL_HWTSTAMP_FLAG_IFR_RESULT)) { + hwtstamp_config_from_kernel(&cfg, &kernel_cfg); - if (copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg))) - return -EFAULT; + if (copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg))) + return -EFAULT; + } return 0; } +int generic_hwtstamp_set_lower(struct net_device *dev, + struct kernel_hwtstamp_config *kernel_cfg, + struct netlink_ext_ack *extack) +{ + const struct net_device_ops *ops = dev->netdev_ops; + struct ifreq ifrr; + int err; + + if (!netif_device_present(dev)) + return -ENODEV; + + if (ops->ndo_hwtstamp_set) { + kernel_cfg->kernel_flags &= ~KERNEL_HWTSTAMP_FLAG_IFR_RESULT; + err = ops->ndo_hwtstamp_set(dev, kernel_cfg, extack); + return err; + } + + if (!kernel_cfg->ifr) + return -EOPNOTSUPP; + + strscpy_pad(ifrr.ifr_name, dev->name, IFNAMSIZ); + ifrr.ifr_ifru = kernel_cfg->ifr->ifr_ifru; + err = dev_eth_ioctl(dev, &ifrr, SIOCSHWTSTAMP); + if (!err) { + kernel_cfg->ifr->ifr_ifru = ifrr.ifr_ifru; + kernel_cfg->kernel_flags |= KERNEL_HWTSTAMP_FLAG_IFR_RESULT; + } + return err; +} +EXPORT_SYMBOL(generic_hwtstamp_set_lower); + +int generic_hwtstamp_get_lower(struct net_device *dev, + struct kernel_hwtstamp_config *kernel_cfg, + struct netlink_ext_ack *extack) +{ + const struct net_device_ops *ops = dev->netdev_ops; + struct ifreq ifrr; + int err; + + if (!netif_device_present(dev)) + return -ENODEV; + + if (ops->ndo_hwtstamp_get) { + kernel_cfg->kernel_flags &= ~KERNEL_HWTSTAMP_FLAG_IFR_RESULT; + err = ops->ndo_hwtstamp_get(dev, kernel_cfg, extack); + return err; + } + + if (!kernel_cfg->ifr) + return -EOPNOTSUPP; + + strscpy_pad(ifrr.ifr_name, dev->name, IFNAMSIZ); + ifrr.ifr_ifru = kernel_cfg->ifr->ifr_ifru; + err = dev_eth_ioctl(dev, &ifrr, SIOCGHWTSTAMP); + if (!err) { + kernel_cfg->ifr->ifr_ifru = ifrr.ifr_ifru; + kernel_cfg->kernel_flags |= KERNEL_HWTSTAMP_FLAG_IFR_RESULT; + } + return err; +} +EXPORT_SYMBOL(generic_hwtstamp_get_lower); + static int dev_siocbond(struct net_device *dev, struct ifreq *ifr, unsigned int cmd) {
--
2.40.1