[NETFILTER]: nf_conntrack: remove old memory allocator of conntrack

Now memory space for help and NAT are allocated by extension
infrastructure.

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/netfilter/nf_conntrack.h

@@ -117,9 +117,6 @@ struct nf_conn
 	/* Unique ID that identifies this conntrack*/
 	unsigned int id;
 
-	/* features - nat, helper, ... used by allocating system */
-	u_int32_t features;
-
 #if defined(CONFIG_NF_CONNTRACK_MARK)
 	u_int32_t mark;
 #endif
@@ -133,9 +130,6 @@ struct nf_conn
 
 	/* Extensions */
 	struct nf_ct_ext *ext;
-
-	/* features dynamically at the end: helper, nat (both optional) */
-	char data[0];
 };
 
 static inline struct nf_conn *
@@ -265,14 +259,6 @@ do {							\
 	local_bh_enable();				\
 } while (0)
 
-/* no helper, no nat */
-#define	NF_CT_F_BASIC	0
-/* for helper */
-#define	NF_CT_F_HELP	1
-/* for nat. */
-#define	NF_CT_F_NAT	2
-#define NF_CT_F_NUM	4
-
 extern int
 nf_conntrack_register_cache(u_int32_t features, const char *name, size_t size);
 extern void

include/net/netfilter/nf_conntrack_l3proto.h

@@ -64,8 +64,6 @@ struct nf_conntrack_l3proto
 	int (*prepare)(struct sk_buff **pskb, unsigned int hooknum,
 		       unsigned int *dataoff, u_int8_t *protonum);
 
-	u_int32_t (*get_features)(const struct nf_conntrack_tuple *tuple);
-
 	int (*tuple_to_nfattr)(struct sk_buff *skb,
 			       const struct nf_conntrack_tuple *t);
 

net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c

@@ -103,11 +103,6 @@ ipv4_prepare(struct sk_buff **pskb, unsigned int hooknum, unsigned int *dataoff,
 	return NF_ACCEPT;
 }
 
-static u_int32_t ipv4_get_features(const struct nf_conntrack_tuple *tuple)
-{
-	return NF_CT_F_BASIC;
-}
-
 static unsigned int ipv4_confirm(unsigned int hooknum,
 				 struct sk_buff **pskb,
 				 const struct net_device *in,
@@ -419,7 +414,6 @@ struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv4 = {
 	.print_tuple	 = ipv4_print_tuple,
 	.print_conntrack = ipv4_print_conntrack,
 	.prepare	 = ipv4_prepare,
-	.get_features	 = ipv4_get_features,
 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
 	.tuple_to_nfattr = ipv4_tuple_to_nfattr,
 	.nfattr_to_tuple = ipv4_nfattr_to_tuple,

net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c

@@ -147,11 +147,6 @@ ipv6_prepare(struct sk_buff **pskb, unsigned int hooknum, unsigned int *dataoff,
 	return NF_ACCEPT;
 }
 
-static u_int32_t ipv6_get_features(const struct nf_conntrack_tuple *tuple)
-{
-	return NF_CT_F_BASIC;
-}
-
 static unsigned int ipv6_confirm(unsigned int hooknum,
 				 struct sk_buff **pskb,
 				 const struct net_device *in,
@@ -397,7 +392,6 @@ struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 = {
 	.ctl_table_path		= nf_net_netfilter_sysctl_path,
 	.ctl_table		= nf_ct_ipv6_sysctl_table,
 #endif
-	.get_features		= ipv6_get_features,
 	.me			= THIS_MODULE,
 };
 

net/netfilter/nf_conntrack_core.c

@@ -71,39 +71,12 @@ EXPORT_SYMBOL_GPL(nf_conntrack_untracked);
 unsigned int nf_ct_log_invalid __read_mostly;
 LIST_HEAD(unconfirmed);
 static int nf_conntrack_vmalloc __read_mostly;
-
+static struct kmem_cache *nf_conntrack_cachep __read_mostly;
 static unsigned int nf_conntrack_next_id;
 
 DEFINE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
 EXPORT_PER_CPU_SYMBOL(nf_conntrack_stat);
 
-/*
- * This scheme offers various size of "struct nf_conn" dependent on
- * features(helper, nat, ...)
- */
-
-#define NF_CT_FEATURES_NAMELEN	256
-static struct {
-	/* name of slab cache. printed in /proc/slabinfo */
-	char *name;
-
-	/* size of slab cache */
-	size_t size;
-
-	/* slab cache pointer */
-	struct kmem_cache *cachep;
-
-	/* allocated slab cache + modules which uses this slab cache */
-	int use;
-
-} nf_ct_cache[NF_CT_F_NUM];
-
-/* protect members of nf_ct_cache except of "use" */
-DEFINE_RWLOCK(nf_ct_cache_lock);
-
-/* This avoids calling kmem_cache_create() with same name simultaneously */
-static DEFINE_MUTEX(nf_ct_cache_mutex);
-
 static int nf_conntrack_hash_rnd_initted;
 static unsigned int nf_conntrack_hash_rnd;
 
@@ -126,122 +99,6 @@ static inline u_int32_t hash_conntrack(const struct nf_conntrack_tuple *tuple)
 				nf_conntrack_hash_rnd);
 }
 
-int nf_conntrack_register_cache(u_int32_t features, const char *name,
-				size_t size)
-{
-	int ret = 0;
-	char *cache_name;
-	struct kmem_cache *cachep;
-
-	DEBUGP("nf_conntrack_register_cache: features=0x%x, name=%s, size=%d\n",
-	       features, name, size);
-
-	if (features < NF_CT_F_BASIC || features >= NF_CT_F_NUM) {
-		DEBUGP("nf_conntrack_register_cache: invalid features.: 0x%x\n",
-			features);
-		return -EINVAL;
-	}
-
-	mutex_lock(&nf_ct_cache_mutex);
-
-	write_lock_bh(&nf_ct_cache_lock);
-	/* e.g: multiple helpers are loaded */
-	if (nf_ct_cache[features].use > 0) {
-		DEBUGP("nf_conntrack_register_cache: already resisterd.\n");
-		if ((!strncmp(nf_ct_cache[features].name, name,
-			      NF_CT_FEATURES_NAMELEN))
-		    && nf_ct_cache[features].size == size) {
-			DEBUGP("nf_conntrack_register_cache: reusing.\n");
-			nf_ct_cache[features].use++;
-			ret = 0;
-		} else
-			ret = -EBUSY;
-
-		write_unlock_bh(&nf_ct_cache_lock);
-		mutex_unlock(&nf_ct_cache_mutex);
-		return ret;
-	}
-	write_unlock_bh(&nf_ct_cache_lock);
-
-	/*
-	 * The memory space for name of slab cache must be alive until
-	 * cache is destroyed.
-	 */
-	cache_name = kmalloc(sizeof(char)*NF_CT_FEATURES_NAMELEN, GFP_ATOMIC);
-	if (cache_name == NULL) {
-		DEBUGP("nf_conntrack_register_cache: can't alloc cache_name\n");
-		ret = -ENOMEM;
-		goto out_up_mutex;
-	}
-
-	if (strlcpy(cache_name, name, NF_CT_FEATURES_NAMELEN)
-						>= NF_CT_FEATURES_NAMELEN) {
-		printk("nf_conntrack_register_cache: name too long\n");
-		ret = -EINVAL;
-		goto out_free_name;
-	}
-
-	cachep = kmem_cache_create(cache_name, size, 0, 0,
-				   NULL, NULL);
-	if (!cachep) {
-		printk("nf_conntrack_register_cache: Can't create slab cache "
-		       "for the features = 0x%x\n", features);
-		ret = -ENOMEM;
-		goto out_free_name;
-	}
-
-	write_lock_bh(&nf_ct_cache_lock);
-	nf_ct_cache[features].use = 1;
-	nf_ct_cache[features].size = size;
-	nf_ct_cache[features].cachep = cachep;
-	nf_ct_cache[features].name = cache_name;
-	write_unlock_bh(&nf_ct_cache_lock);
-
-	goto out_up_mutex;
-
-out_free_name:
-	kfree(cache_name);
-out_up_mutex:
-	mutex_unlock(&nf_ct_cache_mutex);
-	return ret;
-}
-EXPORT_SYMBOL_GPL(nf_conntrack_register_cache);
-
-/* FIXME: In the current, only nf_conntrack_cleanup() can call this function. */
-void nf_conntrack_unregister_cache(u_int32_t features)
-{
-	struct kmem_cache *cachep;
-	char *name;
-
-	/*
-	 * This assures that kmem_cache_create() isn't called before destroying
-	 * slab cache.
-	 */
-	DEBUGP("nf_conntrack_unregister_cache: 0x%04x\n", features);
-	mutex_lock(&nf_ct_cache_mutex);
-
-	write_lock_bh(&nf_ct_cache_lock);
-	if (--nf_ct_cache[features].use > 0) {
-		write_unlock_bh(&nf_ct_cache_lock);
-		mutex_unlock(&nf_ct_cache_mutex);
-		return;
-	}
-	cachep = nf_ct_cache[features].cachep;
-	name = nf_ct_cache[features].name;
-	nf_ct_cache[features].cachep = NULL;
-	nf_ct_cache[features].name = NULL;
-	nf_ct_cache[features].size = 0;
-	write_unlock_bh(&nf_ct_cache_lock);
-
-	synchronize_net();
-
-	kmem_cache_destroy(cachep);
-	kfree(name);
-
-	mutex_unlock(&nf_ct_cache_mutex);
-}
-EXPORT_SYMBOL_GPL(nf_conntrack_unregister_cache);
-
 int
 nf_ct_get_tuple(const struct sk_buff *skb,
 		unsigned int nhoff,
@@ -559,11 +416,8 @@ static int early_drop(struct list_head *chain)
 	return dropped;
 }
 
-static struct nf_conn *
-__nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
-		     const struct nf_conntrack_tuple *repl,
-		     const struct nf_conntrack_l3proto *l3proto,
-		     u_int32_t features)
+struct nf_conn *nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
+				   const struct nf_conntrack_tuple *repl)
 {
 	struct nf_conn *conntrack = NULL;
 
@@ -589,65 +443,28 @@ __nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
 		}
 	}
 
-	/*  find features needed by this conntrack. */
-	features |= l3proto->get_features(orig);
-
-	DEBUGP("nf_conntrack_alloc: features=0x%x\n", features);
-
-	read_lock_bh(&nf_ct_cache_lock);
-
-	if (unlikely(!nf_ct_cache[features].use)) {
-		DEBUGP("nf_conntrack_alloc: not supported features = 0x%x\n",
-			features);
-		goto out;
-	}
-
-	conntrack = kmem_cache_alloc(nf_ct_cache[features].cachep, GFP_ATOMIC);
+	conntrack = kmem_cache_zalloc(nf_conntrack_cachep, GFP_ATOMIC);
 	if (conntrack == NULL) {
-		DEBUGP("nf_conntrack_alloc: Can't alloc conntrack from cache\n");
-		goto out;
+		DEBUGP("nf_conntrack_alloc: Can't alloc conntrack.\n");
+		atomic_dec(&nf_conntrack_count);
+		return ERR_PTR(-ENOMEM);
 	}
 
-	memset(conntrack, 0, nf_ct_cache[features].size);
-	conntrack->features = features;
 	atomic_set(&conntrack->ct_general.use, 1);
 	conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig;
 	conntrack->tuplehash[IP_CT_DIR_REPLY].tuple = *repl;
 	/* Don't set timer yet: wait for confirmation */
 	setup_timer(&conntrack->timeout, death_by_timeout,
 		    (unsigned long)conntrack);
-	read_unlock_bh(&nf_ct_cache_lock);
 
-	return conntrack;
-out:
-	read_unlock_bh(&nf_ct_cache_lock);
-	atomic_dec(&nf_conntrack_count);
 	return conntrack;
 }
-
-struct nf_conn *nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
-				   const struct nf_conntrack_tuple *repl)
-{
-	struct nf_conntrack_l3proto *l3proto;
-	struct nf_conn *ct;
-
-	rcu_read_lock();
-	l3proto = __nf_ct_l3proto_find(orig->src.l3num);
-	ct = __nf_conntrack_alloc(orig, repl, l3proto, 0);
-	rcu_read_unlock();
-
-	return ct;
-}
 EXPORT_SYMBOL_GPL(nf_conntrack_alloc);
 
 void nf_conntrack_free(struct nf_conn *conntrack)
 {
-	u_int32_t features = conntrack->features;
-	NF_CT_ASSERT(features >= NF_CT_F_BASIC && features < NF_CT_F_NUM);
 	nf_ct_ext_free(conntrack);
-	DEBUGP("nf_conntrack_free: features = 0x%x, conntrack=%p\n", features,
-	       conntrack);
-	kmem_cache_free(nf_ct_cache[features].cachep, conntrack);
+	kmem_cache_free(nf_conntrack_cachep, conntrack);
 	atomic_dec(&nf_conntrack_count);
 }
 EXPORT_SYMBOL_GPL(nf_conntrack_free);
@@ -665,14 +482,13 @@ init_conntrack(const struct nf_conntrack_tuple *tuple,
 	struct nf_conn_help *help;
 	struct nf_conntrack_tuple repl_tuple;
 	struct nf_conntrack_expect *exp;
-	u_int32_t features = 0;
 
 	if (!nf_ct_invert_tuple(&repl_tuple, tuple, l3proto, l4proto)) {
 		DEBUGP("Can't invert tuple.\n");
 		return NULL;
 	}
 
-	conntrack = __nf_conntrack_alloc(tuple, &repl_tuple, l3proto, features);
+	conntrack = nf_conntrack_alloc(tuple, &repl_tuple);
 	if (conntrack == NULL || IS_ERR(conntrack)) {
 		DEBUGP("Can't allocate conntrack.\n");
 		return (struct nf_conntrack_tuple_hash *)conntrack;
@@ -1128,8 +944,6 @@ EXPORT_SYMBOL_GPL(nf_conntrack_flush);
    supposed to kill the mall. */
 void nf_conntrack_cleanup(void)
 {
-	int i;
-
 	rcu_assign_pointer(ip_ct_attach, NULL);
 
 	/* This makes sure all current packets have passed through
@@ -1150,14 +964,7 @@ void nf_conntrack_cleanup(void)
 
 	rcu_assign_pointer(nf_ct_destroy, NULL);
 
-	for (i = 0; i < NF_CT_F_NUM; i++) {
-		if (nf_ct_cache[i].use == 0)
-			continue;
-
-		NF_CT_ASSERT(nf_ct_cache[i].use == 1);
-		nf_ct_cache[i].use = 1;
-		nf_conntrack_unregister_cache(i);
-	}
+	kmem_cache_destroy(nf_conntrack_cachep);
 	kmem_cache_destroy(nf_conntrack_expect_cachep);
 	free_conntrack_hash(nf_conntrack_hash, nf_conntrack_vmalloc,
 			    nf_conntrack_htable_size);
@@ -1267,9 +1074,10 @@ int __init nf_conntrack_init(void)
 		goto err_out;
 	}
 
-	ret = nf_conntrack_register_cache(NF_CT_F_BASIC, "nf_conntrack:basic",
-					  sizeof(struct nf_conn));
-	if (ret < 0) {
+	nf_conntrack_cachep = kmem_cache_create("nf_conntrack",
+						sizeof(struct nf_conn),
+						0, 0, NULL, NULL);
+	if (!nf_conntrack_cachep) {
 		printk(KERN_ERR "Unable to create nf_conn slab cache\n");
 		goto err_free_hash;
 	}
@@ -1307,7 +1115,7 @@ out_fini_proto:
 out_free_expect_slab:
 	kmem_cache_destroy(nf_conntrack_expect_cachep);
 err_free_conntrack_slab:
-	nf_conntrack_unregister_cache(NF_CT_F_BASIC);
+	kmem_cache_destroy(nf_conntrack_cachep);
 err_free_hash:
 	free_conntrack_hash(nf_conntrack_hash, nf_conntrack_vmalloc,
 			    nf_conntrack_htable_size);

net/netfilter/nf_conntrack_l3proto_generic.c

@@ -76,12 +76,6 @@ generic_prepare(struct sk_buff **pskb, unsigned int hooknum,
 }
 
 
-static u_int32_t generic_get_features(const struct nf_conntrack_tuple *tuple)
-
-{
-	return NF_CT_F_BASIC;
-}
-
 struct nf_conntrack_l3proto nf_conntrack_l3proto_generic = {
 	.l3proto	 = PF_UNSPEC,
 	.name		 = "unknown",
@@ -90,6 +84,5 @@ struct nf_conntrack_l3proto nf_conntrack_l3proto_generic = {
 	.print_tuple	 = generic_print_tuple,
 	.print_conntrack = generic_print_conntrack,
 	.prepare	 = generic_prepare,
-	.get_features	 = generic_get_features,
 };
 EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_generic);