[RFC v4 4/5] netdev: add netdev_is_upper_master
From: Alexis Bauvin <hidden>
Date: 2018-11-22 11:44:21
Subsystem:
networking drivers, networking [general], the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
In preparation of next patch, this function allows to check if a device
is a master, be it direct or indirect, of another one. It walks up the
master chain until it finds the device, or there is no more master.
This allows to check e.g. if br-blue is a master of eth0:
+----------+
| vrf-blue |
+----+-----+
|
+----+----+
| br-blue |
+----+----+
|
+---+---+
| bond0 |
+--+-+--+
| |
+--+ +--+
| |
+---+--+ +--+---+
| eth0 | | eth1 |
+------+ +------+
Signed-off-by: Alexis Bauvin <redacted>
Reviewed-by: Amine Kherbouche <redacted>
Tested-by: Amine Kherbouche <redacted>
---
include/linux/netdevice.h | 1 +
net/core/dev.c | 17 +++++++++++++++++
2 files changed, 18 insertions(+)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index d837dad24b4c..102f79337d7c 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h@@ -4212,6 +4212,7 @@ void *netdev_lower_dev_get_private(struct net_device *dev, struct net_device *lower_dev); void netdev_lower_state_changed(struct net_device *lower_dev, void *lower_state_info); +bool netdev_is_upper_master(struct net_device *dev, struct net_device *master); /* RSS keys are 40 or 52 bytes long */ #define NETDEV_RSS_KEY_LEN 52
diff --git a/net/core/dev.c b/net/core/dev.c
index 93243479085f..12459036d0da 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c@@ -7225,6 +7225,23 @@ void netdev_lower_state_changed(struct net_device *lower_dev, } EXPORT_SYMBOL(netdev_lower_state_changed); +/** + * netdev_is_upper_master - Test if a device is a master, direct or indirect, + * of another one. + * @dev: device to start looking from + * @master: device to test if master of dev + */ +bool netdev_is_upper_master(struct net_device *dev, struct net_device *master) +{ + if (!dev) + return false; + + if (dev->ifindex == master->ifindex) + return true; + return netdev_is_upper_master(netdev_master_upper_dev_get(dev), master); +} +EXPORT_SYMBOL(netdev_is_upper_master); + static void dev_change_rx_flags(struct net_device *dev, int flags) { const struct net_device_ops *ops = dev->netdev_ops;
--