net: netdevice: Add operation ndo_sk_get_lower_dev

ndo_sk_get_lower_dev returns the lower netdev that corresponds to
a given socket.
Additionally, we implement a helper netdev_sk_get_lowest_dev() to get
the lowest one in chain.

Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Boris Pismenny <borisp@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Tariq Toukan
2021-01-17 16:59:42 +02:00
committed by Jakub Kicinski
parent 41fb4c1ba7
commit 719a402cf6
2 changed files with 37 additions and 0 deletions

View File

@ -8105,6 +8105,39 @@ struct net_device *netdev_get_xmit_slave(struct net_device *dev,
}
EXPORT_SYMBOL(netdev_get_xmit_slave);
static struct net_device *netdev_sk_get_lower_dev(struct net_device *dev,
struct sock *sk)
{
const struct net_device_ops *ops = dev->netdev_ops;
if (!ops->ndo_sk_get_lower_dev)
return NULL;
return ops->ndo_sk_get_lower_dev(dev, sk);
}
/**
* netdev_sk_get_lowest_dev - Get the lowest device in chain given device and socket
* @dev: device
* @sk: the socket
*
* %NULL is returned if no lower device is found.
*/
struct net_device *netdev_sk_get_lowest_dev(struct net_device *dev,
struct sock *sk)
{
struct net_device *lower;
lower = netdev_sk_get_lower_dev(dev, sk);
while (lower) {
dev = lower;
lower = netdev_sk_get_lower_dev(dev, sk);
}
return dev;
}
EXPORT_SYMBOL(netdev_sk_get_lowest_dev);
static void netdev_adjacent_add_links(struct net_device *dev)
{
struct netdev_adjacent *iter;