From 0c17270f9b920e4e1777488f1911bbfdaf2af3be Mon Sep 17 00:00:00 2001 From: Yajun Deng Date: Thu, 12 Jun 2025 14:27:07 +0000 Subject: [PATCH] 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: Yajun Deng Reviewed-by: Simon Horman Link: https://patch.msgid.link/20250612142707.4644-1-yajun.deng@linux.dev Signed-off-by: Jakub Kicinski --- include/linux/netdevice.h | 2 +- net/core/net-sysfs.c | 59 +++++++++++++++++++++++---------------- 2 files changed, 36 insertions(+), 25 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index adb14db257984..9cbc4e54b7e4a 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -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; diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index 1ace0cd01adce..c9b9693863999 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -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; -- 2.47.2