net: GRE: Add is_gretap_dev, is_ip6gretap_dev

Determining whether a device is a GRE device is easily done by
inspecting struct net_device.type. However, for the tap variants, the
type is just ARPHRD_ETHER.

Therefore introduce two predicate functions that use netdev_ops to tell
the tap devices.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/gre.h b/include/net/gre.h
index f90585decbce647789d145d48c9ccd6615dc8a49..797142eee9cdec2c6cbc67fdaeaaa98a5aeddd24 100644 (file)
--- a/include/net/gre.h
+++ b/include/net/gre.h
@@ -37,6 +37,9 @@ struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
 int gre_parse_header(struct sk_buff *skb, struct tnl_ptk_info *tpi,
                     bool *csum_err, __be16 proto, int nhs);
 
+bool is_gretap_dev(const struct net_device *dev);
+bool is_ip6gretap_dev(const struct net_device *dev);
+
 static inline int gre_calc_hlen(__be16 o_flags)
 {
        int addend = 4;

diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index e496afa47709fb477aa6af76ae806be28617adfb..0fe1d69b5df41e6470b2aa8997bf0bc979afbe4f 100644 (file)
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -1323,6 +1323,12 @@ static void ipgre_tap_setup(struct net_device *dev)
        ip_tunnel_setup(dev, gre_tap_net_id);
 }
 
+bool is_gretap_dev(const struct net_device *dev)
+{
+       return dev->netdev_ops == &gre_tap_netdev_ops;
+}
+EXPORT_SYMBOL_GPL(is_gretap_dev);
+
 static int ipgre_newlink(struct net *src_net, struct net_device *dev,
                         struct nlattr *tb[], struct nlattr *data[],
                         struct netlink_ext_ack *extack)

diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index 3026662a6413e94d08e8ce0590fd46a8c84ccf7b..4f150a394387f069f926fe3b7c18f7cff7d6ca08 100644 (file)
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -1785,6 +1785,12 @@ static void ip6gre_tap_setup(struct net_device *dev)
        netif_keep_dst(dev);
 }
 
+bool is_ip6gretap_dev(const struct net_device *dev)
+{
+       return dev->netdev_ops == &ip6gre_tap_netdev_ops;
+}
+EXPORT_SYMBOL_GPL(is_ip6gretap_dev);
+
 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
                                       struct ip_tunnel_encap *ipencap)
 {