[INET]: Consolidate xxx_find() in fragment management

Here we need another callback ->match to check whether the
entry found in hash matches the key passed. The key used 
is the same as the creation argument for inet_frag_create.

Yet again, this ->match is the same for netfilter and ipv6.
Running a frew steps forward - this callback will later
replace the ->equal one.

Since the inet_frag_find() uses the already consolidated
inet_frag_create() remove the xxx_frag_create from protocol
codes.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/inet_frag.h

@@ -45,6 +45,8 @@ struct inet_frags {
 	void			(*skb_free)(struct sk_buff *);
 	int			(*equal)(struct inet_frag_queue *q1,
 					 struct inet_frag_queue *q2);
+	int			(*match)(struct inet_frag_queue *q,
+						void *arg);
 	void			(*frag_expire)(unsigned long data);
 };
 
@@ -55,8 +57,8 @@ void inet_frag_kill(struct inet_frag_queue *q, struct inet_frags *f);
 void inet_frag_destroy(struct inet_frag_queue *q,
 				struct inet_frags *f, int *work);
 int inet_frag_evictor(struct inet_frags *f);
-struct inet_frag_queue *inet_frag_create(struct inet_frags *f,
-		void *create_arg, unsigned int hash);
+struct inet_frag_queue *inet_frag_find(struct inet_frags *f, void *key,
+		unsigned int hash);
 
 static inline void inet_frag_put(struct inet_frag_queue *q, struct inet_frags *f)
 {

include/net/ipv6.h

@@ -387,6 +387,7 @@ struct ip6_create_arg {
 };
 
 void ip6_frag_init(struct inet_frag_queue *q, void *a);
+int ip6_frag_match(struct inet_frag_queue *q, void *a);
 
 static inline int ipv6_addr_any(const struct in6_addr *a)
 {

net/ipv4/inet_fragment.c

@@ -226,8 +226,8 @@ static struct inet_frag_queue *inet_frag_alloc(struct inet_frags *f, void *arg)
 	return q;
 }
 
-struct inet_frag_queue *inet_frag_create(struct inet_frags *f, void *arg,
-		unsigned int hash)
+static struct inet_frag_queue *inet_frag_create(struct inet_frags *f,
+		void *arg, unsigned int hash)
 {
 	struct inet_frag_queue *q;
 
@@ -237,4 +237,23 @@ struct inet_frag_queue *inet_frag_create(struct inet_frags *f, void *arg,
 
 	return inet_frag_intern(q, f, hash);
 }
-EXPORT_SYMBOL(inet_frag_create);
+
+struct inet_frag_queue *inet_frag_find(struct inet_frags *f, void *key,
+		unsigned int hash)
+{
+	struct inet_frag_queue *q;
+	struct hlist_node *n;
+
+	read_lock(&f->lock);
+	hlist_for_each_entry(q, n, &f->hash[hash], list) {
+		if (f->match(q, key)) {
+			atomic_inc(&q->refcnt);
+			read_unlock(&f->lock);
+			return q;
+		}
+	}
+	read_unlock(&f->lock);
+
+	return inet_frag_create(f, key, hash);
+}
+EXPORT_SYMBOL(inet_frag_find);

net/ipv4/ip_fragment.c

@@ -142,6 +142,19 @@ static int ip4_frag_equal(struct inet_frag_queue *q1,
 			qp1->user == qp2->user);
 }
 
+static int ip4_frag_match(struct inet_frag_queue *q, void *a)
+{
+	struct ipq *qp;
+	struct ip4_create_arg *arg = a;
+
+	qp = container_of(q, struct ipq, q);
+	return (qp->id == arg->iph->id &&
+			qp->saddr == arg->iph->saddr &&
+			qp->daddr == arg->iph->daddr &&
+			qp->protocol == arg->iph->protocol &&
+			qp->user == arg->user);
+}
+
 /* Memory Tracking Functions. */
 static __inline__ void frag_kfree_skb(struct sk_buff *skb, int *work)
 {
@@ -235,18 +248,20 @@ static void ip_expire(unsigned long arg)
 	ipq_put(qp);
 }
 
-/* Creation primitives. */
-
-/* Add an entry to the 'ipq' queue for a newly received IP datagram. */
-static struct ipq *ip_frag_create(struct iphdr *iph, u32 user, unsigned int h)
+/* Find the correct entry in the "incomplete datagrams" queue for
+ * this IP datagram, and create new one, if nothing is found.
+ */
+static inline struct ipq *ip_find(struct iphdr *iph, u32 user)
 {
 	struct inet_frag_queue *q;
 	struct ip4_create_arg arg;
+	unsigned int hash;
 
 	arg.iph = iph;
 	arg.user = user;
+	hash = ipqhashfn(iph->id, iph->saddr, iph->daddr, iph->protocol);
 
-	q = inet_frag_create(&ip4_frags, &arg, h);
+	q = inet_frag_find(&ip4_frags, &arg, hash);
 	if (q == NULL)
 		goto out_nomem;
 
@@ -257,37 +272,6 @@ static struct ipq *ip_frag_create(struct iphdr *iph, u32 user, unsigned int h)
 	return NULL;
 }
 
-/* Find the correct entry in the "incomplete datagrams" queue for
- * this IP datagram, and create new one, if nothing is found.
- */
-static inline struct ipq *ip_find(struct iphdr *iph, u32 user)
-{
-	__be16 id = iph->id;
-	__be32 saddr = iph->saddr;
-	__be32 daddr = iph->daddr;
-	__u8 protocol = iph->protocol;
-	unsigned int hash;
-	struct ipq *qp;
-	struct hlist_node *n;
-
-	read_lock(&ip4_frags.lock);
-	hash = ipqhashfn(id, saddr, daddr, protocol);
-	hlist_for_each_entry(qp, n, &ip4_frags.hash[hash], q.list) {
-		if (qp->id == id		&&
-		    qp->saddr == saddr	&&
-		    qp->daddr == daddr	&&
-		    qp->protocol == protocol &&
-		    qp->user == user) {
-			atomic_inc(&qp->q.refcnt);
-			read_unlock(&ip4_frags.lock);
-			return qp;
-		}
-	}
-	read_unlock(&ip4_frags.lock);
-
-	return ip_frag_create(iph, user, hash);
-}
-
 /* Is the fragment too far ahead to be part of ipq? */
 static inline int ip_frag_too_far(struct ipq *qp)
 {
@@ -648,6 +632,7 @@ void __init ipfrag_init(void)
 	ip4_frags.skb_free = NULL;
 	ip4_frags.qsize = sizeof(struct ipq);
 	ip4_frags.equal = ip4_frag_equal;
+	ip4_frags.match = ip4_frag_match;
 	ip4_frags.frag_expire = ip_expire;
 	inet_frags_init(&ip4_frags);
 }

net/ipv6/netfilter/nf_conntrack_reasm.c

@@ -176,18 +176,19 @@ static void nf_ct_frag6_expire(unsigned long data)
 
 /* Creation primitives. */
 
-static struct nf_ct_frag6_queue *
-nf_ct_frag6_create(unsigned int hash, __be32 id, struct in6_addr *src,
-		struct in6_addr *dst)
+static __inline__ struct nf_ct_frag6_queue *
+fq_find(__be32 id, struct in6_addr *src, struct in6_addr *dst)
 {
 	struct inet_frag_queue *q;
 	struct ip6_create_arg arg;
+	unsigned int hash;
 
 	arg.id = id;
 	arg.src = src;
 	arg.dst = dst;
+	hash = ip6qhashfn(id, src, dst);
 
-	q = inet_frag_create(&nf_frags, &arg, hash);
+	q = inet_frag_find(&nf_frags, &arg, hash);
 	if (q == NULL)
 		goto oom;
 
@@ -198,28 +199,6 @@ nf_ct_frag6_create(unsigned int hash, __be32 id, struct in6_addr *src,
 	return NULL;
 }
 
-static __inline__ struct nf_ct_frag6_queue *
-fq_find(__be32 id, struct in6_addr *src, struct in6_addr *dst)
-{
-	struct nf_ct_frag6_queue *fq;
-	struct hlist_node *n;
-	unsigned int hash = ip6qhashfn(id, src, dst);
-
-	read_lock(&nf_frags.lock);
-	hlist_for_each_entry(fq, n, &nf_frags.hash[hash], q.list) {
-		if (fq->id == id &&
-		    ipv6_addr_equal(src, &fq->saddr) &&
-		    ipv6_addr_equal(dst, &fq->daddr)) {
-			atomic_inc(&fq->q.refcnt);
-			read_unlock(&nf_frags.lock);
-			return fq;
-		}
-	}
-	read_unlock(&nf_frags.lock);
-
-	return nf_ct_frag6_create(hash, id, src, dst);
-}
-
 
 static int nf_ct_frag6_queue(struct nf_ct_frag6_queue *fq, struct sk_buff *skb,
 			     struct frag_hdr *fhdr, int nhoff)
@@ -706,6 +685,7 @@ int nf_ct_frag6_init(void)
 	nf_frags.destructor = nf_frag_free;
 	nf_frags.skb_free = nf_skb_free;
 	nf_frags.qsize = sizeof(struct nf_ct_frag6_queue);
+	nf_frags.match = ip6_frag_match;
 	nf_frags.equal = ip6_frag_equal;
 	nf_frags.frag_expire = nf_ct_frag6_expire;
 	inet_frags_init(&nf_frags);

net/ipv6/reassembly.c

@@ -155,6 +155,18 @@ int ip6_frag_equal(struct inet_frag_queue *q1, struct inet_frag_queue *q2)
 }
 EXPORT_SYMBOL(ip6_frag_equal);
 
+int ip6_frag_match(struct inet_frag_queue *q, void *a)
+{
+	struct frag_queue *fq;
+	struct ip6_create_arg *arg = a;
+
+	fq = container_of(q, struct frag_queue, q);
+	return (fq->id == arg->id &&
+			ipv6_addr_equal(&fq->saddr, arg->src) &&
+			ipv6_addr_equal(&fq->daddr, arg->dst));
+}
+EXPORT_SYMBOL(ip6_frag_match);
+
 /* Memory Tracking Functions. */
 static inline void frag_kfree_skb(struct sk_buff *skb, int *work)
 {
@@ -245,20 +257,20 @@ static void ip6_frag_expire(unsigned long data)
 	fq_put(fq);
 }
 
-/* Creation primitives. */
-
-static struct frag_queue *
-ip6_frag_create(__be32 id, struct in6_addr *src, struct in6_addr *dst,
-		struct inet6_dev *idev, unsigned int hash)
+static __inline__ struct frag_queue *
+fq_find(__be32 id, struct in6_addr *src, struct in6_addr *dst,
+	struct inet6_dev *idev)
 {
 	struct inet_frag_queue *q;
 	struct ip6_create_arg arg;
+	unsigned int hash;
 
 	arg.id = id;
 	arg.src = src;
 	arg.dst = dst;
+	hash = ip6qhashfn(id, src, dst);
 
-	q = inet_frag_create(&ip6_frags, &arg, hash);
+	q = inet_frag_find(&ip6_frags, &arg, hash);
 	if (q == NULL)
 		goto oom;
 
@@ -269,31 +281,6 @@ ip6_frag_create(__be32 id, struct in6_addr *src, struct in6_addr *dst,
 	return NULL;
 }
 
-static __inline__ struct frag_queue *
-fq_find(__be32 id, struct in6_addr *src, struct in6_addr *dst,
-	struct inet6_dev *idev)
-{
-	struct frag_queue *fq;
-	struct hlist_node *n;
-	unsigned int hash;
-
-	read_lock(&ip6_frags.lock);
-	hash = ip6qhashfn(id, src, dst);
-	hlist_for_each_entry(fq, n, &ip6_frags.hash[hash], q.list) {
-		if (fq->id == id &&
-		    ipv6_addr_equal(src, &fq->saddr) &&
-		    ipv6_addr_equal(dst, &fq->daddr)) {
-			atomic_inc(&fq->q.refcnt);
-			read_unlock(&ip6_frags.lock);
-			return fq;
-		}
-	}
-	read_unlock(&ip6_frags.lock);
-
-	return ip6_frag_create(id, src, dst, idev, hash);
-}
-
-
 static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,
 			   struct frag_hdr *fhdr, int nhoff)
 {
@@ -673,6 +660,7 @@ void __init ipv6_frag_init(void)
 	ip6_frags.destructor = ip6_frag_free;
 	ip6_frags.skb_free = NULL;
 	ip6_frags.qsize = sizeof(struct frag_queue);
+	ip6_frags.match = ip6_frag_match;
 	ip6_frags.equal = ip6_frag_equal;
 	ip6_frags.frag_expire = ip6_frag_expire;
 	inet_frags_init(&ip6_frags);