From: Tariq Toukan <tariqt@nvidia.com>
Date: Sun, 17 Jan 2021 16:59:42 +0200
Subject: net: netdevice: Add operation ndo_sk_get_lower_dev
Patch-mainline: v5.12-rc1
Git-commit: 719a402cf60311b1cdff3f6320abaecdcc5e46b7
References: bsc#1181719
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>
Acked-by: Michal Kubecek <mkubecek@suse.cz>
---
include/linux/netdevice.h | 4 ++++
net/core/dev.c | 33 +++++++++++++++++++++++++++++++++
2 files changed, 37 insertions(+)
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1407,6 +1407,8 @@ struct net_device_ops {
struct net_device* (*ndo_get_xmit_slave)(struct net_device *dev,
struct sk_buff *skb,
bool all_slaves);
+ struct net_device* (*ndo_sk_get_lower_dev)(struct net_device *dev,
+ struct sock *sk);
netdev_features_t (*ndo_fix_features)(struct net_device *dev,
netdev_features_t features);
int (*ndo_set_features)(struct net_device *dev,
@@ -2823,6 +2825,8 @@ int init_dummy_netdev(struct net_device *dev);
struct net_device *netdev_get_xmit_slave(struct net_device *dev,
struct sk_buff *skb,
bool all_slaves);
+struct net_device *netdev_sk_get_lowest_dev(struct net_device *dev,
+ struct sock *sk);
struct net_device *dev_get_by_index(struct net *net, int ifindex);
struct net_device *__dev_get_by_index(struct net *net, int ifindex);
struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex);
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -7987,6 +7987,39 @@ 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;