Commit 0c17270f authored by Yajun Deng's avatar Yajun Deng Committed by Jakub Kicinski
Browse files

net: sysfs: Implement is_visible for phys_(port_id, port_name, switch_id) 



phys_port_id_show, phys_port_name_show and phys_switch_id_show would
return -EOPNOTSUPP if the netdev didn't implement the corresponding
method.

There is no point in creating these files if they are unsupported.

Put these attributes in netdev_phys_group and implement the is_visible
method. make phys_(port_id, port_name, switch_id) invisible if the netdev
dosen't implement the corresponding method.

Signed-off-by: default avatarYajun Deng <yajun.deng@linux.dev>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250612142707.4644-1-yajun.deng@linux.dev


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent ffe8a490

include/linux/netdevice.h

+1 −1
Original line number Diff line number Diff line
@@ -2388,7 +2388,7 @@ struct net_device { 
	struct dm_hw_stat_delta __rcu *dm_private;

#endif

	struct device		dev;

	const struct attribute_group *sysfs_groups[4];

	const struct attribute_group *sysfs_groups[5];

	const struct attribute_group *sysfs_rx_queue_group;



	const struct rtnl_link_ops *rtnl_link_ops;

net/core/net-sysfs.c

+35 −24
Original line number Diff line number Diff line
@@ -641,12 +641,6 @@ static ssize_t phys_port_id_show(struct device *dev, 
	struct netdev_phys_item_id ppid;

	ssize_t ret;



	/* The check is also done in dev_get_phys_port_id; this helps returning

	 * early without hitting the locking section below.

	 */

	if (!netdev->netdev_ops->ndo_get_phys_port_id)

		return -EOPNOTSUPP;



	ret = sysfs_rtnl_lock(&dev->kobj, &attr->attr, netdev);

	if (ret)

		return ret;
@@ -668,13 +662,6 @@ static ssize_t phys_port_name_show(struct device *dev, 
	char name[IFNAMSIZ];

	ssize_t ret;



	/* The checks are also done in dev_get_phys_port_name; this helps

	 * returning early without hitting the locking section below.

	 */

	if (!netdev->netdev_ops->ndo_get_phys_port_name &&

	    !netdev->devlink_port)

		return -EOPNOTSUPP;



	ret = sysfs_rtnl_lock(&dev->kobj, &attr->attr, netdev);

	if (ret)

		return ret;
@@ -696,14 +683,6 @@ static ssize_t phys_switch_id_show(struct device *dev, 
	struct netdev_phys_item_id ppid = { };

	ssize_t ret;



	/* The checks are also done in dev_get_phys_port_name; this helps

	 * returning early without hitting the locking section below. This works

	 * because recurse is false when calling dev_get_port_parent_id.

	 */

	if (!netdev->netdev_ops->ndo_get_port_parent_id &&

	    !netdev->devlink_port)

		return -EOPNOTSUPP;



	ret = sysfs_rtnl_lock(&dev->kobj, &attr->attr, netdev);

	if (ret)

		return ret;
@@ -718,6 +697,40 @@ static ssize_t phys_switch_id_show(struct device *dev, 
}

static DEVICE_ATTR_RO(phys_switch_id);



static struct attribute *netdev_phys_attrs[] __ro_after_init = {

	&dev_attr_phys_port_id.attr,

	&dev_attr_phys_port_name.attr,

	&dev_attr_phys_switch_id.attr,

	NULL,

};



static umode_t netdev_phys_is_visible(struct kobject *kobj,

				      struct attribute *attr, int index)

{

	struct device *dev = kobj_to_dev(kobj);

	struct net_device *netdev = to_net_dev(dev);



	if (attr == &dev_attr_phys_port_id.attr) {

		if (!netdev->netdev_ops->ndo_get_phys_port_id)

			return 0;

	} else if (attr == &dev_attr_phys_port_name.attr) {

		if (!netdev->netdev_ops->ndo_get_phys_port_name &&

		    !netdev->devlink_port)

			return 0;

	} else if (attr == &dev_attr_phys_switch_id.attr) {

		if (!netdev->netdev_ops->ndo_get_port_parent_id &&

		    !netdev->devlink_port)

			return 0;

	}



	return attr->mode;

}



static const struct attribute_group netdev_phys_group = {

	.attrs = netdev_phys_attrs,

	.is_visible = netdev_phys_is_visible,

};



static ssize_t threaded_show(struct device *dev,

			     struct device_attribute *attr, char *buf)

{
@@ -783,9 +796,6 @@ static struct attribute *net_class_attrs[] __ro_after_init = { 
	&dev_attr_tx_queue_len.attr,

	&dev_attr_gro_flush_timeout.attr,

	&dev_attr_napi_defer_hard_irqs.attr,

	&dev_attr_phys_port_id.attr,

	&dev_attr_phys_port_name.attr,

	&dev_attr_phys_switch_id.attr,

	&dev_attr_proto_down.attr,

	&dev_attr_carrier_up_count.attr,

	&dev_attr_carrier_down_count.attr,
@@ -2328,6 +2338,7 @@ int netdev_register_kobject(struct net_device *ndev) 
		groups++;



	*groups++ = &netstat_group;

	*groups++ = &netdev_phys_group;



	if (wireless_group_needed(ndev))

		*groups++ = &wireless_group;