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Diffstat (limited to 'net/ipv4/route.c')
-rw-r--r--net/ipv4/route.c90
1 files changed, 66 insertions, 24 deletions
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 28205e5bfa9..278f46f5011 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -131,8 +131,8 @@ static int ip_rt_min_advmss __read_mostly = 256;
static int ip_rt_secret_interval __read_mostly = 10 * 60 * HZ;
static int rt_chain_length_max __read_mostly = 20;
-static void rt_worker_func(struct work_struct *work);
-static DECLARE_DELAYED_WORK(expires_work, rt_worker_func);
+static struct delayed_work expires_work;
+static unsigned long expires_ljiffies;
/*
* Interface to generic destination cache.
@@ -787,9 +787,12 @@ static void rt_check_expire(void)
struct rtable *rth, *aux, **rthp;
unsigned long samples = 0;
unsigned long sum = 0, sum2 = 0;
+ unsigned long delta;
u64 mult;
- mult = ((u64)ip_rt_gc_interval) << rt_hash_log;
+ delta = jiffies - expires_ljiffies;
+ expires_ljiffies = jiffies;
+ mult = ((u64)delta) << rt_hash_log;
if (ip_rt_gc_timeout > 1)
do_div(mult, ip_rt_gc_timeout);
goal = (unsigned int)mult;
@@ -1064,7 +1067,8 @@ work_done:
out: return 0;
}
-static int rt_intern_hash(unsigned hash, struct rtable *rt, struct rtable **rp)
+static int rt_intern_hash(unsigned hash, struct rtable *rt,
+ struct rtable **rp, struct sk_buff *skb)
{
struct rtable *rth, **rthp;
unsigned long now;
@@ -1081,8 +1085,35 @@ restart:
now = jiffies;
if (!rt_caching(dev_net(rt->u.dst.dev))) {
- rt_drop(rt);
- return 0;
+ /*
+ * If we're not caching, just tell the caller we
+ * were successful and don't touch the route. The
+ * caller hold the sole reference to the cache entry, and
+ * it will be released when the caller is done with it.
+ * If we drop it here, the callers have no way to resolve routes
+ * when we're not caching. Instead, just point *rp at rt, so
+ * the caller gets a single use out of the route
+ * Note that we do rt_free on this new route entry, so that
+ * once its refcount hits zero, we are still able to reap it
+ * (Thanks Alexey)
+ * Note also the rt_free uses call_rcu. We don't actually
+ * need rcu protection here, this is just our path to get
+ * on the route gc list.
+ */
+
+ if (rt->rt_type == RTN_UNICAST || rt->fl.iif == 0) {
+ int err = arp_bind_neighbour(&rt->u.dst);
+ if (err) {
+ if (net_ratelimit())
+ printk(KERN_WARNING
+ "Neighbour table failure & not caching routes.\n");
+ rt_drop(rt);
+ return err;
+ }
+ }
+
+ rt_free(rt);
+ goto skip_hashing;
}
rthp = &rt_hash_table[hash].chain;
@@ -1114,7 +1145,10 @@ restart:
spin_unlock_bh(rt_hash_lock_addr(hash));
rt_drop(rt);
- *rp = rth;
+ if (rp)
+ *rp = rth;
+ else
+ skb_dst_set(skb, &rth->u.dst);
return 0;
}
@@ -1196,7 +1230,8 @@ restart:
#if RT_CACHE_DEBUG >= 2
if (rt->u.dst.rt_next) {
struct rtable *trt;
- printk(KERN_DEBUG "rt_cache @%02x: %pI4", hash, &rt->rt_dst);
+ printk(KERN_DEBUG "rt_cache @%02x: %pI4",
+ hash, &rt->rt_dst);
for (trt = rt->u.dst.rt_next; trt; trt = trt->u.dst.rt_next)
printk(" . %pI4", &trt->rt_dst);
printk("\n");
@@ -1210,7 +1245,12 @@ restart:
rcu_assign_pointer(rt_hash_table[hash].chain, rt);
spin_unlock_bh(rt_hash_lock_addr(hash));
- *rp = rt;
+
+skip_hashing:
+ if (rp)
+ *rp = rt;
+ else
+ skb_dst_set(skb, &rt->u.dst);
return 0;
}
@@ -1407,7 +1447,7 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
&netevent);
rt_del(hash, rth);
- if (!rt_intern_hash(hash, rt, &rt))
+ if (!rt_intern_hash(hash, rt, &rt, NULL))
ip_rt_put(rt);
goto do_next;
}
@@ -1473,7 +1513,7 @@ static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
void ip_rt_send_redirect(struct sk_buff *skb)
{
- struct rtable *rt = skb->rtable;
+ struct rtable *rt = skb_rtable(skb);
struct in_device *in_dev = in_dev_get(rt->u.dst.dev);
if (!in_dev)
@@ -1521,7 +1561,7 @@ out:
static int ip_error(struct sk_buff *skb)
{
- struct rtable *rt = skb->rtable;
+ struct rtable *rt = skb_rtable(skb);
unsigned long now;
int code;
@@ -1698,7 +1738,7 @@ static void ipv4_link_failure(struct sk_buff *skb)
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
- rt = skb->rtable;
+ rt = skb_rtable(skb);
if (rt)
dst_set_expires(&rt->u.dst, 0);
}
@@ -1858,7 +1898,7 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
in_dev_put(in_dev);
hash = rt_hash(daddr, saddr, dev->ifindex, rt_genid(dev_net(dev)));
- return rt_intern_hash(hash, rth, &skb->rtable);
+ return rt_intern_hash(hash, rth, NULL, skb);
e_nobufs:
in_dev_put(in_dev);
@@ -2019,7 +2059,7 @@ static int ip_mkroute_input(struct sk_buff *skb,
/* put it into the cache */
hash = rt_hash(daddr, saddr, fl->iif,
rt_genid(dev_net(rth->u.dst.dev)));
- return rt_intern_hash(hash, rth, &skb->rtable);
+ return rt_intern_hash(hash, rth, NULL, skb);
}
/*
@@ -2175,7 +2215,7 @@ local_input:
}
rth->rt_type = res.type;
hash = rt_hash(daddr, saddr, fl.iif, rt_genid(net));
- err = rt_intern_hash(hash, rth, &skb->rtable);
+ err = rt_intern_hash(hash, rth, NULL, skb);
goto done;
no_route:
@@ -2244,7 +2284,7 @@ int ip_route_input(struct sk_buff *skb, __be32 daddr, __be32 saddr,
dst_use(&rth->u.dst, jiffies);
RT_CACHE_STAT_INC(in_hit);
rcu_read_unlock();
- skb->rtable = rth;
+ skb_dst_set(skb, &rth->u.dst);
return 0;
}
RT_CACHE_STAT_INC(in_hlist_search);
@@ -2420,7 +2460,7 @@ static int ip_mkroute_output(struct rtable **rp,
if (err == 0) {
hash = rt_hash(oldflp->fl4_dst, oldflp->fl4_src, oldflp->oif,
rt_genid(dev_net(dev_out)));
- err = rt_intern_hash(hash, rth, rp);
+ err = rt_intern_hash(hash, rth, rp, NULL);
}
return err;
@@ -2763,7 +2803,7 @@ static int rt_fill_info(struct net *net,
struct sk_buff *skb, u32 pid, u32 seq, int event,
int nowait, unsigned int flags)
{
- struct rtable *rt = skb->rtable;
+ struct rtable *rt = skb_rtable(skb);
struct rtmsg *r;
struct nlmsghdr *nlh;
long expires;
@@ -2907,7 +2947,7 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void
err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev);
local_bh_enable();
- rt = skb->rtable;
+ rt = skb_rtable(skb);
if (err == 0 && rt->u.dst.error)
err = -rt->u.dst.error;
} else {
@@ -2927,7 +2967,7 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void
if (err)
goto errout_free;
- skb->rtable = rt;
+ skb_dst_set(skb, &rt->u.dst);
if (rtm->rtm_flags & RTM_F_NOTIFY)
rt->rt_flags |= RTCF_NOTIFY;
@@ -2968,15 +3008,15 @@ int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb)
continue;
if (rt_is_expired(rt))
continue;
- skb->dst = dst_clone(&rt->u.dst);
+ skb_dst_set(skb, dst_clone(&rt->u.dst));
if (rt_fill_info(net, skb, NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq, RTM_NEWROUTE,
1, NLM_F_MULTI) <= 0) {
- dst_release(xchg(&skb->dst, NULL));
+ skb_dst_drop(skb);
rcu_read_unlock_bh();
goto done;
}
- dst_release(xchg(&skb->dst, NULL));
+ skb_dst_drop(skb);
}
rcu_read_unlock_bh();
}
@@ -3390,6 +3430,8 @@ int __init ip_rt_init(void)
/* All the timers, started at system startup tend
to synchronize. Perturb it a bit.
*/
+ INIT_DELAYED_WORK_DEFERRABLE(&expires_work, rt_worker_func);
+ expires_ljiffies = jiffies;
schedule_delayed_work(&expires_work,
net_random() % ip_rt_gc_interval + ip_rt_gc_interval);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-04-01 11:30:35 +0000