From 6a6d6681ac1add9655b7ab5dd0b46b54aeb1b44f Mon Sep 17 00:00:00 2001 From: Alexis Bauvin Date: Mon, 3 Dec 2018 10:54:39 +0100 Subject: l3mdev: add function to retreive upper master Existing functions to retreive the l3mdev of a device did not walk the master chain to find the upper master. This patch adds a function to find the l3mdev, even indirect through e.g. a bridge: +----------+ | | | vrf-blue | | | +----+-----+ | | +----+-----+ | | | br-blue | | | +----+-----+ | | +----+-----+ | | | eth0 | | | +----------+ This will properly resolve the l3mdev of eth0 to vrf-blue. Signed-off-by: Alexis Bauvin Reviewed-by: Amine Kherbouche Reviewed-by: David Ahern Tested-by: Amine Kherbouche Signed-off-by: David S. Miller --- net/l3mdev/l3mdev.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'net/l3mdev/l3mdev.c') diff --git a/net/l3mdev/l3mdev.c b/net/l3mdev/l3mdev.c index 8da86ceca33d..309dee76724e 100644 --- a/net/l3mdev/l3mdev.c +++ b/net/l3mdev/l3mdev.c @@ -46,6 +46,24 @@ int l3mdev_master_ifindex_rcu(const struct net_device *dev) } EXPORT_SYMBOL_GPL(l3mdev_master_ifindex_rcu); +/** + * l3mdev_master_upper_ifindex_by_index - get index of upper l3 master + * device + * @net: network namespace for device index lookup + * @ifindex: targeted interface + */ +int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex) +{ + struct net_device *dev; + + dev = dev_get_by_index_rcu(net, ifindex); + while (dev && !netif_is_l3_master(dev)) + dev = netdev_master_upper_dev_get(dev); + + return dev ? dev->ifindex : 0; +} +EXPORT_SYMBOL_GPL(l3mdev_master_upper_ifindex_by_index_rcu); + /** * l3mdev_fib_table - get FIB table id associated with an L3 * master interface -- cgit v1.2.3