[INET]: Consolidate xxx_frag_intern
This routine checks for the existence of a given entry
in the hash table and inserts the new one if needed.
The ->equal callback is used to compare two frag_queue-s
together, but this one is temporary and will be removed
later. The netfilter code and the ipv6 one use the same
routine to compare frags.
The inet_frag_intern() always returns non-NULL pointer,
so convert the inet_frag_queue into protocol specific
one (with the container_of) without any checks.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/inet_fragment.c b/net/ipv4/inet_fragment.c
index 484cf51..15054eb 100644
--- a/net/ipv4/inet_fragment.c
+++ b/net/ipv4/inet_fragment.c
@@ -172,3 +172,40 @@
return evicted;
}
EXPORT_SYMBOL(inet_frag_evictor);
+
+struct inet_frag_queue *inet_frag_intern(struct inet_frag_queue *qp_in,
+ struct inet_frags *f, unsigned int hash)
+{
+ struct inet_frag_queue *qp;
+#ifdef CONFIG_SMP
+ struct hlist_node *n;
+#endif
+
+ write_lock(&f->lock);
+#ifdef CONFIG_SMP
+ /* With SMP race we have to recheck hash table, because
+ * such entry could be created on other cpu, while we
+ * promoted read lock to write lock.
+ */
+ hlist_for_each_entry(qp, n, &f->hash[hash], list) {
+ if (f->equal(qp, qp_in)) {
+ atomic_inc(&qp->refcnt);
+ write_unlock(&f->lock);
+ qp_in->last_in |= COMPLETE;
+ inet_frag_put(qp_in, f);
+ return qp;
+ }
+ }
+#endif
+ qp = qp_in;
+ if (!mod_timer(&qp->timer, jiffies + f->ctl->timeout))
+ atomic_inc(&qp->refcnt);
+
+ atomic_inc(&qp->refcnt);
+ hlist_add_head(&qp->list, &f->hash[hash]);
+ list_add_tail(&qp->lru_list, &f->lru_list);
+ f->nqueues++;
+ write_unlock(&f->lock);
+ return qp;
+}
+EXPORT_SYMBOL(inet_frag_intern);