A later patch wants access to the fib result on an output route lookup
with the rcu lock held. Refactor __ip_route_output_key_hash, pushing
the logic between rcu_read_lock ... rcu_read_unlock into a new helper
that takes the fib_result as an input arg.
To keep the name length under control remove the leading underscores
from the name. _rcu is added to the name of the new helper indicating
it is called with the rcu read lock held.
Signed-off-by: David Ahern <d...@cumulusnetworks.com>
---
include/net/route.h | 9 ++++++---
net/ipv4/icmp.c | 4 ++--
net/ipv4/route.c | 50 +++++++++++++++++++++++++++++---------------------
3 files changed, 37 insertions(+), 26 deletions(-)
diff --git a/include/net/route.h b/include/net/route.h
index c0874c87c173..bf4f7a98f753 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -113,13 +113,16 @@ struct in_device;
int ip_rt_init(void);
void rt_cache_flush(struct net *net);
void rt_flush_dev(struct net_device *dev);
-struct rtable *__ip_route_output_key_hash(struct net *, struct flowi4 *flp,
- int mp_hash);
+struct rtable *ip_route_output_key_hash(struct net *, struct flowi4 *flp,
+ int mp_hash);
+struct rtable *ip_route_output_key_hash_rcu(struct net *, struct flowi4 *flp,
+ struct fib_result *res,
+ int mp_hash);
static inline struct rtable *__ip_route_output_key(struct net *net,
struct flowi4 *flp)
{
- return __ip_route_output_key_hash(net, flp, -1);
+ return ip_route_output_key_hash(net, flp, -1);
}
struct rtable *ip_route_output_flow(struct net *, struct flowi4 *flp,
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 0777ea949223..67ed57365f80 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -482,8 +482,8 @@ static struct rtable *icmp_route_lookup(struct net *net,
fl4->flowi4_oif = l3mdev_master_ifindex(skb_dst(skb_in)->dev);
security_skb_classify_flow(skb_in, flowi4_to_flowi(fl4));
- rt = __ip_route_output_key_hash(net, fl4,
- icmp_multipath_hash_skb(skb_in));
+ rt = ip_route_output_key_hash(net, fl4,
+ icmp_multipath_hash_skb(skb_in));
if (IS_ERR(rt))
return rt;
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 7144288371cf..effd7f8e31f9 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2181,29 +2181,39 @@ static struct rtable *__mkroute_output(const struct
fib_result *res,
* Major route resolver routine.
*/
-struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
- int mp_hash)
+struct rtable *ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
+ int mp_hash)
{
- struct net_device *dev_out = NULL;
__u8 tos = RT_FL_TOS(fl4);
- unsigned int flags = 0;
struct fib_result res;
struct rtable *rth;
- int orig_oif;
- int err = -ENETUNREACH;
res.tclassid = 0;
res.fi = NULL;
res.table = NULL;
- orig_oif = fl4->flowi4_oif;
-
fl4->flowi4_iif = LOOPBACK_IFINDEX;
fl4->flowi4_tos = tos & IPTOS_RT_MASK;
fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
rcu_read_lock();
+ rth = ip_route_output_key_hash_rcu(net, fl4, &res, mp_hash);
+ rcu_read_unlock();
+
+ return rth;
+}
+EXPORT_SYMBOL_GPL(ip_route_output_key_hash);
+
+struct rtable *ip_route_output_key_hash_rcu(struct net *net, struct flowi4
*fl4,
+ struct fib_result *res, int mp_hash)
+{
+ struct net_device *dev_out = NULL;
+ int orig_oif = fl4->flowi4_oif;
+ unsigned int flags = 0;
+ struct rtable *rth;
+ int err = -ENETUNREACH;
+
if (fl4->saddr) {
rth = ERR_PTR(-EINVAL);
if (ipv4_is_multicast(fl4->saddr) ||
@@ -2289,15 +2299,15 @@ struct rtable *__ip_route_output_key_hash(struct net
*net, struct flowi4 *fl4,
fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK);
dev_out = net->loopback_dev;
fl4->flowi4_oif = LOOPBACK_IFINDEX;
- res.type = RTN_LOCAL;
+ res->type = RTN_LOCAL;
flags |= RTCF_LOCAL;
goto make_route;
}
- err = fib_lookup(net, fl4, &res, 0);
+ err = fib_lookup(net, fl4, res, 0);
if (err) {
- res.fi = NULL;
- res.table = NULL;
+ res->fi = NULL;
+ res->table = NULL;
if (fl4->flowi4_oif &&
(ipv4_is_multicast(fl4->daddr) ||
!netif_index_is_l3_master(net, fl4->flowi4_oif))) {
@@ -2322,17 +2332,17 @@ struct rtable *__ip_route_output_key_hash(struct net
*net, struct flowi4 *fl4,
if (fl4->saddr == 0)
fl4->saddr = inet_select_addr(dev_out, 0,
RT_SCOPE_LINK);
- res.type = RTN_UNICAST;
+ res->type = RTN_UNICAST;
goto make_route;
}
rth = ERR_PTR(err);
goto out;
}
- if (res.type == RTN_LOCAL) {
+ if (res->type == RTN_LOCAL) {
if (!fl4->saddr) {
- if (res.fi->fib_prefsrc)
- fl4->saddr = res.fi->fib_prefsrc;
+ if (res->fi->fib_prefsrc)
+ fl4->saddr = res->fi->fib_prefsrc;
else
fl4->saddr = fl4->daddr;
}
@@ -2344,20 +2354,18 @@ struct rtable *__ip_route_output_key_hash(struct net
*net, struct flowi4 *fl4,
goto make_route;
}
- fib_select_path(net, &res, fl4, mp_hash);
+ fib_select_path(net, res, fl4, mp_hash);
- dev_out = FIB_RES_DEV(res);
+ dev_out = FIB_RES_DEV(*res);
fl4->flowi4_oif = dev_out->ifindex;
make_route:
- rth = __mkroute_output(&res, fl4, orig_oif, dev_out, flags);
+ rth = __mkroute_output(res, fl4, orig_oif, dev_out, flags);
out:
- rcu_read_unlock();
return rth;
}
-EXPORT_SYMBOL_GPL(__ip_route_output_key_hash);
static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32
cookie)
{
--
2.1.4
