[PATCH RFC v2 net-next 13/21] net/ipv6: Add rt6_info create function for ip6_pol_route_lookup
From: David Ahern <hidden>
Date: 2018-03-19 03:37:47
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
ip6_pol_route_lookup is the lookup function for ip6_route_lookup and rt6_lookup. At the moment it returns either a reference to a FIB entry or a cached exception. To move FIB entries to a separate struct, this lookup function needs to convert FIB entries to an rt6_info that is returned to the caller. Signed-off-by: David Ahern <redacted> --- net/ipv6/route.c | 30 ++++++++++++++++++++++++++---- 1 file changed, 26 insertions(+), 4 deletions(-)
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 86ee78633697..39fd9f88912f 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c@@ -1055,6 +1055,20 @@ static bool ip6_hold_safe(struct net *net, struct rt6_info **prt, return false; } +/* called with rcu_lock held */ +static struct rt6_info *ip6_create_rt_rcu(struct rt6_info *rt) +{ + struct net_device *dev; + struct rt6_info *nrt; + + dev = ip6_rt_get_dev_rcu(rt); + nrt = __ip6_dst_alloc(dev_net(dev), dev, 0); + if (nrt) + ip6_rt_copy_init(nrt, rt); + + return nrt; +} + static struct rt6_info *ip6_pol_route_lookup(struct net *net, struct fib6_table *table, struct flowi6 *fl6,
@@ -1084,18 +1098,26 @@ static struct rt6_info *ip6_pol_route_lookup(struct net *net, } /* Search through exception table */ rt_cache = rt6_find_cached_rt(rt, &fl6->daddr, &fl6->saddr); - if (rt_cache) + if (rt_cache) { rt = rt_cache; + if (ip6_hold_safe(net, &rt, true)) + dst_use_noref(&rt->dst, jiffies); + } else if (dst_hold_safe(&rt->dst)) { + struct rt6_info *nrt; - if (ip6_hold_safe(net, &rt, true)) - dst_use_noref(&rt->dst, jiffies); + nrt = ip6_create_rt_rcu(rt); + dst_release(&rt->dst); + rt = nrt; + } else { + rt = net->ipv6.ip6_null_entry; + dst_hold(&rt->dst); + } rcu_read_unlock(); trace_fib6_table_lookup(net, rt, table, fl6); return rt; - } struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
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2.11.0