diff mbox series

[v8,net-next,01/12] net: add NDOs for configuring hardware timestamping

Message ID 20230717152709.574773-2-vladimir.oltean@nxp.com (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series Introduce ndo_hwtstamp_get() and ndo_hwtstamp_set() | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next, async
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 5488 this patch: 5488
netdev/cc_maintainers success CCed 9 of 9 maintainers
netdev/build_clang success Errors and warnings before: 2273 this patch: 2273
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 5728 this patch: 5728
netdev/checkpatch warning WARNING: line length of 84 exceeds 80 columns WARNING: line length of 95 exceeds 80 columns WARNING: line length of 97 exceeds 80 columns WARNING: line length of 98 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Vladimir Oltean July 17, 2023, 3:26 p.m. UTC 
From: Maxim Georgiev <glipus@gmail.com>

Current hardware timestamping API for NICs requires implementing
.ndo_eth_ioctl() for SIOCGHWTSTAMP and SIOCSHWTSTAMP.

That API has some boilerplate such as request parameter translation
between user and kernel address spaces, handling possible translation
failures correctly, etc. Since it is the same all across the board, it
would be desirable to handle it through generic code.

Here we introduce .ndo_hwtstamp_get() and .ndo_hwtstamp_set(), which
implement that boilerplate and allow drivers to just act upon requests.

Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Maxim Georgiev <glipus@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Horatiu Vultur <horatiu.vultur@microchip.com>
---
Changes in v8:
- None
Changes in v7:
- Remove extack from ndo_hwtstamp_get()
- Reword commit message
Changes in v6:
- The patch title was updated. No code changes.
Changes in v4:
- Renamed hwtstamp_kernel_to_config() function to
  hwtstamp_config_from_kernel().
- Added struct kernel_hwtstamp_config zero initialization
  in dev_get_hwtstamp() and in dev_get_hwtstamp().
Changes in v3:
- Moved individual driver conversions to separate patches
Changes in v2:
- Introduced kernel_hwtstamp_config structure
- Added netlink_ext_ack* and kernel_hwtstamp_config* as NDO hw timestamp
  function parameters
- Reodered function variable declarations in dev_hwtstamp()
- Refactored error handling logic in dev_hwtstamp()
- Split dev_hwtstamp() into GET and SET versions
- Changed net_hwtstamp_validate() to accept struct hwtstamp_config *
  as a parameter

 include/linux/net_tstamp.h |  8 +++++++
 include/linux/netdevice.h  | 16 +++++++++++++
 net/core/dev_ioctl.c       | 46 ++++++++++++++++++++++++++++++++++++--
 3 files changed, 68 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/include/linux/net_tstamp.h b/include/linux/net_tstamp.h
index fd67f3cc0c4b..7c59824f43f5 100644
--- a/include/linux/net_tstamp.h
+++ b/include/linux/net_tstamp.h
@@ -30,4 +30,12 @@  static inline void hwtstamp_config_to_kernel(struct kernel_hwtstamp_config *kern
 	kernel_cfg->rx_filter = cfg->rx_filter;
 }
 
+static inline void hwtstamp_config_from_kernel(struct hwtstamp_config *cfg,
+					       const struct kernel_hwtstamp_config *kernel_cfg)
+{
+	cfg->flags = kernel_cfg->flags;
+	cfg->tx_type = kernel_cfg->tx_type;
+	cfg->rx_filter = kernel_cfg->rx_filter;
+}
+
 #endif /* _LINUX_NET_TIMESTAMPING_H_ */
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index b828c7a75be2..17a442ed683b 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -57,6 +57,7 @@ 
 struct netpoll_info;
 struct device;
 struct ethtool_ops;
+struct kernel_hwtstamp_config;
 struct phy_device;
 struct dsa_port;
 struct ip_tunnel_parm;
@@ -1418,6 +1419,16 @@  struct netdev_net_notifier {
  *	Get hardware timestamp based on normal/adjustable time or free running
  *	cycle counter. This function is required if physical clock supports a
  *	free running cycle counter.
+ *
+ * int (*ndo_hwtstamp_get)(struct net_device *dev,
+ *			   struct kernel_hwtstamp_config *kernel_config);
+ *	Get the currently configured hardware timestamping parameters for the
+ *	NIC device.
+ *
+ * int (*ndo_hwtstamp_set)(struct net_device *dev,
+ *			   struct kernel_hwtstamp_config *kernel_config,
+ *			   struct netlink_ext_ack *extack);
+ *	Change the hardware timestamping parameters for NIC device.
  */
 struct net_device_ops {
 	int			(*ndo_init)(struct net_device *dev);
@@ -1652,6 +1663,11 @@  struct net_device_ops {
 	ktime_t			(*ndo_get_tstamp)(struct net_device *dev,
 						  const struct skb_shared_hwtstamps *hwtstamps,
 						  bool cycles);
+	int			(*ndo_hwtstamp_get)(struct net_device *dev,
+						    struct kernel_hwtstamp_config *kernel_config);
+	int			(*ndo_hwtstamp_set)(struct net_device *dev,
+						    struct kernel_hwtstamp_config *kernel_config,
+						    struct netlink_ext_ack *extack);
 };
 
 struct xdp_metadata_ops {
diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c
index 3730945ee294..10c0e173b38b 100644
--- a/net/core/dev_ioctl.c
+++ b/net/core/dev_ioctl.c
@@ -254,11 +254,32 @@  static int dev_eth_ioctl(struct net_device *dev,
 
 static int dev_get_hwtstamp(struct net_device *dev, struct ifreq *ifr)
 {
-	return dev_eth_ioctl(dev, ifr, SIOCGHWTSTAMP);
+	const struct net_device_ops *ops = dev->netdev_ops;
+	struct kernel_hwtstamp_config kernel_cfg = {};
+	struct hwtstamp_config cfg;
+	int err;
+
+	if (!ops->ndo_hwtstamp_get)
+		return dev_eth_ioctl(dev, ifr, SIOCGHWTSTAMP); /* legacy */
+
+	if (!netif_device_present(dev))
+		return -ENODEV;
+
+	err = ops->ndo_hwtstamp_get(dev, &kernel_cfg);
+	if (err)
+		return err;
+
+	hwtstamp_config_from_kernel(&cfg, &kernel_cfg);
+
+	if (copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg)))
+		return -EFAULT;
+
+	return 0;
 }
 
 static int dev_set_hwtstamp(struct net_device *dev, struct ifreq *ifr)
 {
+	const struct net_device_ops *ops = dev->netdev_ops;
 	struct kernel_hwtstamp_config kernel_cfg;
 	struct netlink_ext_ack extack = {};
 	struct hwtstamp_config cfg;
@@ -280,7 +301,28 @@  static int dev_set_hwtstamp(struct net_device *dev, struct ifreq *ifr)
 		return err;
 	}
 
-	return dev_eth_ioctl(dev, ifr, SIOCSHWTSTAMP);
+	if (!ops->ndo_hwtstamp_set)
+		return dev_eth_ioctl(dev, ifr, SIOCSHWTSTAMP); /* legacy */
+
+	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);
+		return err;
+	}
+
+	/* The driver may have modified the configuration, so copy the
+	 * updated version of it back to user space
+	 */
+	hwtstamp_config_from_kernel(&cfg, &kernel_cfg);
+
+	if (copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg)))
+		return -EFAULT;
+
+	return 0;
 }
 
 static int dev_siocbond(struct net_device *dev,