net: Abstract away all dst_entry metrics accesses.
Use helper functions to hide all direct accesses, especially writes,
to dst_entry metrics values.
This will allow us to:
1) More easily change how the metrics are stored.
2) Implement COW for metrics.
In particular this will help us put metrics into the inetpeer
cache if that is what we end up doing. We can make the _metrics
member a pointer instead of an array, initially have it point
at the read-only metrics in the FIB, and then on the first set
grab an inetpeer entry and point the _metrics member there.
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 3843c2d..26ac396 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1686,11 +1686,14 @@
if (mtu < dst_mtu(&rth->dst)) {
dst_confirm(&rth->dst);
if (mtu < ip_rt_min_pmtu) {
+ u32 lock = dst_metric(&rth->dst,
+ RTAX_LOCK);
mtu = ip_rt_min_pmtu;
- rth->dst.metrics[RTAX_LOCK-1] |=
- (1 << RTAX_MTU);
+ lock |= (1 << RTAX_MTU);
+ dst_metric_set(&rth->dst, RTAX_LOCK,
+ lock);
}
- rth->dst.metrics[RTAX_MTU-1] = mtu;
+ dst_metric_set(&rth->dst, RTAX_MTU, mtu);
dst_set_expires(&rth->dst,
ip_rt_mtu_expires);
}
@@ -1708,10 +1711,11 @@
if (dst_mtu(dst) > mtu && mtu >= 68 &&
!(dst_metric_locked(dst, RTAX_MTU))) {
if (mtu < ip_rt_min_pmtu) {
+ u32 lock = dst_metric(dst, RTAX_LOCK);
mtu = ip_rt_min_pmtu;
- dst->metrics[RTAX_LOCK-1] |= (1 << RTAX_MTU);
+ dst_metric_set(dst, RTAX_LOCK, lock | (1 << RTAX_MTU));
}
- dst->metrics[RTAX_MTU-1] = mtu;
+ dst_metric_set(dst, RTAX_MTU, mtu);
dst_set_expires(dst, ip_rt_mtu_expires);
call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst);
}
@@ -1796,36 +1800,37 @@
static void rt_set_nexthop(struct rtable *rt, struct fib_result *res, u32 itag)
{
+ struct dst_entry *dst = &rt->dst;
struct fib_info *fi = res->fi;
if (fi) {
if (FIB_RES_GW(*res) &&
FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
rt->rt_gateway = FIB_RES_GW(*res);
- memcpy(rt->dst.metrics, fi->fib_metrics,
- sizeof(rt->dst.metrics));
+ dst_import_metrics(dst, fi->fib_metrics);
if (fi->fib_mtu == 0) {
- rt->dst.metrics[RTAX_MTU-1] = rt->dst.dev->mtu;
- if (dst_metric_locked(&rt->dst, RTAX_MTU) &&
+ dst_metric_set(dst, RTAX_MTU, dst->dev->mtu);
+ if (dst_metric_locked(dst, RTAX_MTU) &&
rt->rt_gateway != rt->rt_dst &&
- rt->dst.dev->mtu > 576)
- rt->dst.metrics[RTAX_MTU-1] = 576;
+ dst->dev->mtu > 576)
+ dst_metric_set(dst, RTAX_MTU, 576);
}
#ifdef CONFIG_NET_CLS_ROUTE
- rt->dst.tclassid = FIB_RES_NH(*res).nh_tclassid;
+ dst->tclassid = FIB_RES_NH(*res).nh_tclassid;
#endif
} else
- rt->dst.metrics[RTAX_MTU-1]= rt->dst.dev->mtu;
+ dst_metric_set(dst, RTAX_MTU, dst->dev->mtu);
- if (dst_metric(&rt->dst, RTAX_HOPLIMIT) == 0)
- rt->dst.metrics[RTAX_HOPLIMIT-1] = sysctl_ip_default_ttl;
- if (dst_mtu(&rt->dst) > IP_MAX_MTU)
- rt->dst.metrics[RTAX_MTU-1] = IP_MAX_MTU;
- if (dst_metric(&rt->dst, RTAX_ADVMSS) == 0)
- rt->dst.metrics[RTAX_ADVMSS-1] = max_t(unsigned int, rt->dst.dev->mtu - 40,
- ip_rt_min_advmss);
- if (dst_metric(&rt->dst, RTAX_ADVMSS) > 65535 - 40)
- rt->dst.metrics[RTAX_ADVMSS-1] = 65535 - 40;
+ if (dst_metric(dst, RTAX_HOPLIMIT) == 0)
+ dst_metric_set(dst, RTAX_HOPLIMIT, sysctl_ip_default_ttl);
+ if (dst_mtu(dst) > IP_MAX_MTU)
+ dst_metric_set(dst, RTAX_MTU, IP_MAX_MTU);
+ if (dst_metric(dst, RTAX_ADVMSS) == 0)
+ dst_metric_set(dst, RTAX_ADVMSS,
+ max_t(unsigned int, dst->dev->mtu - 40,
+ ip_rt_min_advmss));
+ if (dst_metric(dst, RTAX_ADVMSS) > 65535 - 40)
+ dst_metric_set(dst, RTAX_ADVMSS, 65535 - 40);
#ifdef CONFIG_NET_CLS_ROUTE
#ifdef CONFIG_IP_MULTIPLE_TABLES
@@ -2720,7 +2725,7 @@
new->__use = 1;
new->input = dst_discard;
new->output = dst_discard;
- memcpy(new->metrics, ort->dst.metrics, RTAX_MAX*sizeof(u32));
+ dst_copy_metrics(new, &ort->dst);
new->dev = ort->dst.dev;
if (new->dev)
@@ -2827,7 +2832,7 @@
if (rt->rt_dst != rt->rt_gateway)
NLA_PUT_BE32(skb, RTA_GATEWAY, rt->rt_gateway);
- if (rtnetlink_put_metrics(skb, rt->dst.metrics) < 0)
+ if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
goto nla_put_failure;
if (rt->fl.mark)