Commit c92b9655 authored by Julian Anastasov's avatar Julian Anastasov Committed by David S. Miller

ipv4: Add FLOWI_FLAG_KNOWN_NH

Add flag to request that output route should be
returned with known rt_gateway, in case we want to use
it as nexthop for neighbour resolving.

	The returned route can be cached as follows:

- in NH exception: because the cached routes are not shared
	with other destinations
- in FIB NH: when using gateway because all destinations for
	NH share same gateway

	As last option, to return rt_gateway!=0 we have to
set DST_NOCACHE.
Signed-off-by: default avatarJulian Anastasov <ja@ssi.bg>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 155e8336
...@@ -21,6 +21,7 @@ struct flowi_common { ...@@ -21,6 +21,7 @@ struct flowi_common {
__u8 flowic_flags; __u8 flowic_flags;
#define FLOWI_FLAG_ANYSRC 0x01 #define FLOWI_FLAG_ANYSRC 0x01
#define FLOWI_FLAG_CAN_SLEEP 0x02 #define FLOWI_FLAG_CAN_SLEEP 0x02
#define FLOWI_FLAG_KNOWN_NH 0x04
__u32 flowic_secid; __u32 flowic_secid;
}; };
......
...@@ -1762,6 +1762,7 @@ static struct rtable *__mkroute_output(const struct fib_result *res, ...@@ -1762,6 +1762,7 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
struct in_device *in_dev; struct in_device *in_dev;
u16 type = res->type; u16 type = res->type;
struct rtable *rth; struct rtable *rth;
bool do_cache;
in_dev = __in_dev_get_rcu(dev_out); in_dev = __in_dev_get_rcu(dev_out);
if (!in_dev) if (!in_dev)
...@@ -1798,24 +1799,36 @@ static struct rtable *__mkroute_output(const struct fib_result *res, ...@@ -1798,24 +1799,36 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
} }
fnhe = NULL; fnhe = NULL;
do_cache = fi != NULL;
if (fi) { if (fi) {
struct rtable __rcu **prth; struct rtable __rcu **prth;
struct fib_nh *nh = &FIB_RES_NH(*res);
fnhe = find_exception(&FIB_RES_NH(*res), fl4->daddr); fnhe = find_exception(nh, fl4->daddr);
if (fnhe) if (fnhe)
prth = &fnhe->fnhe_rth; prth = &fnhe->fnhe_rth;
else else {
prth = __this_cpu_ptr(FIB_RES_NH(*res).nh_pcpu_rth_output); if (unlikely(fl4->flowi4_flags &
FLOWI_FLAG_KNOWN_NH &&
!(nh->nh_gw &&
nh->nh_scope == RT_SCOPE_LINK))) {
do_cache = false;
goto add;
}
prth = __this_cpu_ptr(nh->nh_pcpu_rth_output);
}
rth = rcu_dereference(*prth); rth = rcu_dereference(*prth);
if (rt_cache_valid(rth)) { if (rt_cache_valid(rth)) {
dst_hold(&rth->dst); dst_hold(&rth->dst);
return rth; return rth;
} }
} }
add:
rth = rt_dst_alloc(dev_out, rth = rt_dst_alloc(dev_out,
IN_DEV_CONF_GET(in_dev, NOPOLICY), IN_DEV_CONF_GET(in_dev, NOPOLICY),
IN_DEV_CONF_GET(in_dev, NOXFRM), IN_DEV_CONF_GET(in_dev, NOXFRM),
fi); do_cache);
if (!rth) if (!rth)
return ERR_PTR(-ENOBUFS); return ERR_PTR(-ENOBUFS);
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment