static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label)
{
struct ip6_flowlabel *fl;
read_lock_bh(&ip6_fl_lock);
fl = __fl_lookup(net, label);
if (fl)
atomic_inc(&fl->users);
read_unlock_bh(&ip6_fl_lock);
return fl;
}
static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label)
{
struct ip6_flowlabel *fl;
rcu_read_lock_bh();
fl = __fl_lookup(net, label);
if (fl && !atomic_inc_not_zero(&fl->users))
fl = NULL;
rcu_read_unlock_bh();
return fl;
}
static struct ip6_flowlabel *fl_intern(struct net *net,
struct ip6_flowlabel *fl, __be32 label)
{
struct ip6_flowlabel *lfl;
fl->label = label & IPV6_FLOWLABEL_MASK;
write_lock_bh(&ip6_fl_lock);
if (label == 0) {
for (;;) {
fl->label = htonl(net_random())&IPV6_FLOWLABEL_MASK;
if (fl->label) {
lfl = __fl_lookup(net, fl->label);
if (lfl == NULL)
break;
}
}
} else {
/*
* we dropper the ip6_fl_lock, so this entry could reappear
* and we need to recheck with it.
*
* OTOH no need to search the active socket first, like it is
* done in ipv6_flowlabel_opt - sock is locked, so new entry
* with the same label can only appear on another sock
*/
lfl = __fl_lookup(net, fl->label);
if (lfl != NULL) {
atomic_inc(&lfl->users);
write_unlock_bh(&ip6_fl_lock);
return lfl;
}
}
fl->lastuse = jiffies;
fl->next = fl_ht[FL_HASH(fl->label)];
fl_ht[FL_HASH(fl->label)] = fl;
atomic_inc(&fl_size);
write_unlock_bh(&ip6_fl_lock);
return NULL;
}
static int fl_intern(struct ip6_flowlabel *fl, __be32 label)
{
fl->label = label & IPV6_FLOWLABEL_MASK;
write_lock_bh(&ip6_fl_lock);
if (label == 0) {
for (;;) {
fl->label = htonl(net_random())&IPV6_FLOWLABEL_MASK;
if (fl->label) {
struct ip6_flowlabel *lfl;
lfl = __fl_lookup(fl->label);
if (lfl == NULL)
break;
}
}
}
fl->lastuse = jiffies;
fl->next = fl_ht[FL_HASH(fl->label)];
fl_ht[FL_HASH(fl->label)] = fl;
atomic_inc(&fl_size);
write_unlock_bh(&ip6_fl_lock);
return 0;
}
