net: flow: Add l3mdev flow update

Add l3mdev hook to set FLOWI_FLAG_SKIP_NH_OIF flag and update oif/iif
in flow struct if its oif or iif points to a device enslaved to an L3
Master device. Only 1 needs to be converted to match the l3mdev FIB
rule. This moves the flow adjustment for l3mdev to a single point
catching all lookups. It is redundant for existing hooks (those are
removed in later patches) but is needed for missed lookups such as
PMTU updates.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David Ahern 2016-09-10 12:09:52 -07:00 committed by David S. Miller
parent cf9932a941
commit 9ee0034b8f
4 changed files with 47 additions and 0 deletions

View file

@ -49,6 +49,8 @@ struct l3mdev_ops {
int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
struct fib_lookup_arg *arg);
void l3mdev_update_flow(struct net *net, struct flowi *fl);
int l3mdev_master_ifindex_rcu(const struct net_device *dev);
static inline int l3mdev_master_ifindex(struct net_device *dev)
{
@ -290,6 +292,10 @@ int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
{
return 1;
}
static inline
void l3mdev_update_flow(struct net *net, struct flowi *fl)
{
}
#endif
#endif /* _NET_L3MDEV_H_ */

View file

@ -56,6 +56,9 @@ int __fib_lookup(struct net *net, struct flowi4 *flp,
};
int err;
/* update flow if oif or iif point to device enslaved to l3mdev */
l3mdev_update_flow(net, flowi4_to_flowi(flp));
err = fib_rules_lookup(net->ipv4.rules_ops, flowi4_to_flowi(flp), 0, &arg);
#ifdef CONFIG_IP_ROUTE_CLASSID
if (arg.rule)

View file

@ -38,6 +38,9 @@ struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
.flags = FIB_LOOKUP_NOREF,
};
/* update flow if oif or iif point to device enslaved to l3mdev */
l3mdev_update_flow(net, flowi6_to_flowi(fl6));
fib_rules_lookup(net->ipv6.fib6_rules_ops,
flowi6_to_flowi(fl6), flags, &arg);

View file

@ -222,3 +222,38 @@ int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
return rc;
}
void l3mdev_update_flow(struct net *net, struct flowi *fl)
{
struct net_device *dev;
int ifindex;
rcu_read_lock();
if (fl->flowi_oif) {
dev = dev_get_by_index_rcu(net, fl->flowi_oif);
if (dev) {
ifindex = l3mdev_master_ifindex_rcu(dev);
if (ifindex) {
fl->flowi_oif = ifindex;
fl->flowi_flags |= FLOWI_FLAG_SKIP_NH_OIF;
goto out;
}
}
}
if (fl->flowi_iif) {
dev = dev_get_by_index_rcu(net, fl->flowi_iif);
if (dev) {
ifindex = l3mdev_master_ifindex_rcu(dev);
if (ifindex) {
fl->flowi_iif = ifindex;
fl->flowi_flags |= FLOWI_FLAG_SKIP_NH_OIF;
}
}
}
out:
rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(l3mdev_update_flow);