[NETFILTER]: nf_nat: switch rwlock to spinlock
Since we're using RCU, all users of nf_nat_lock take a write_lock.
Switch it to a spinlock.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/netfilter/nf_nat_core.c b/net/ipv4/netfilter/nf_nat_core.c
index c7a985f..dd07362 100644
--- a/net/ipv4/netfilter/nf_nat_core.c
+++ b/net/ipv4/netfilter/nf_nat_core.c
@@ -31,7 +31,7 @@
#include <net/netfilter/nf_conntrack_l3proto.h>
#include <net/netfilter/nf_conntrack_l4proto.h>
-static DEFINE_RWLOCK(nf_nat_lock);
+static DEFINE_SPINLOCK(nf_nat_lock);
static struct nf_conntrack_l3proto *l3proto __read_mostly;
@@ -330,12 +330,12 @@
unsigned int srchash;
srchash = hash_by_src(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
- write_lock_bh(&nf_nat_lock);
+ spin_lock_bh(&nf_nat_lock);
/* nf_conntrack_alter_reply might re-allocate exntension aera */
nat = nfct_nat(ct);
nat->ct = ct;
hlist_add_head_rcu(&nat->bysource, &bysource[srchash]);
- write_unlock_bh(&nf_nat_lock);
+ spin_unlock_bh(&nf_nat_lock);
}
/* It's done. */
@@ -521,14 +521,14 @@
{
int ret = 0;
- write_lock_bh(&nf_nat_lock);
+ spin_lock_bh(&nf_nat_lock);
if (nf_nat_protos[proto->protonum] != &nf_nat_unknown_protocol) {
ret = -EBUSY;
goto out;
}
rcu_assign_pointer(nf_nat_protos[proto->protonum], proto);
out:
- write_unlock_bh(&nf_nat_lock);
+ spin_unlock_bh(&nf_nat_lock);
return ret;
}
EXPORT_SYMBOL(nf_nat_protocol_register);
@@ -536,10 +536,10 @@
/* Noone stores the protocol anywhere; simply delete it. */
void nf_nat_protocol_unregister(const struct nf_nat_protocol *proto)
{
- write_lock_bh(&nf_nat_lock);
+ spin_lock_bh(&nf_nat_lock);
rcu_assign_pointer(nf_nat_protos[proto->protonum],
&nf_nat_unknown_protocol);
- write_unlock_bh(&nf_nat_lock);
+ spin_unlock_bh(&nf_nat_lock);
synchronize_rcu();
}
EXPORT_SYMBOL(nf_nat_protocol_unregister);
@@ -594,10 +594,10 @@
NF_CT_ASSERT(nat->ct->status & IPS_NAT_DONE_MASK);
- write_lock_bh(&nf_nat_lock);
+ spin_lock_bh(&nf_nat_lock);
hlist_del_rcu(&nat->bysource);
nat->ct = NULL;
- write_unlock_bh(&nf_nat_lock);
+ spin_unlock_bh(&nf_nat_lock);
}
static void nf_nat_move_storage(struct nf_conn *conntrack, void *old)
@@ -609,10 +609,10 @@
if (!ct || !(ct->status & IPS_NAT_DONE_MASK))
return;
- write_lock_bh(&nf_nat_lock);
+ spin_lock_bh(&nf_nat_lock);
hlist_replace_rcu(&old_nat->bysource, &new_nat->bysource);
new_nat->ct = ct;
- write_unlock_bh(&nf_nat_lock);
+ spin_unlock_bh(&nf_nat_lock);
}
static struct nf_ct_ext_type nat_extend __read_mostly = {
@@ -646,13 +646,13 @@
}
/* Sew in builtin protocols. */
- write_lock_bh(&nf_nat_lock);
+ spin_lock_bh(&nf_nat_lock);
for (i = 0; i < MAX_IP_NAT_PROTO; i++)
rcu_assign_pointer(nf_nat_protos[i], &nf_nat_unknown_protocol);
rcu_assign_pointer(nf_nat_protos[IPPROTO_TCP], &nf_nat_protocol_tcp);
rcu_assign_pointer(nf_nat_protos[IPPROTO_UDP], &nf_nat_protocol_udp);
rcu_assign_pointer(nf_nat_protos[IPPROTO_ICMP], &nf_nat_protocol_icmp);
- write_unlock_bh(&nf_nat_lock);
+ spin_unlock_bh(&nf_nat_lock);
/* Initialize fake conntrack so that NAT will skip it */
nf_conntrack_untracked.status |= IPS_NAT_DONE_MASK;