netfilter: nf_tables: convert hash and rbtree to set extensions

The set implementations' private struct will only contain the elements
needed to maintain the search structure, all other elements are moved
to the set extensions.

Element allocation and initialization is performed centrally by
nf_tables_api instead of by the different set implementations'
->insert() functions. A new "elemsize" member in the set ops specifies
the amount of memory to reserve for internal usage. Destruction
will also be moved out of the set implementations by a following patch.

Except for element allocation, the patch is a simple conversion to
using data from the extension area.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 20 insertions, 44 deletions

diff --git a/net/netfilter/nft_rbtree.c b/net/netfilter/nft_rbtree.c
index 2c75361077f7..ebf6e60df41c 100644
--- a/net/netfilter/nft_rbtree.c
+++ b/net/netfilter/nft_rbtree.c
@@ -26,9 +26,7 @@ struct nft_rbtree {
 
 struct nft_rbtree_elem {
 	struct rb_node		node;
-	u16			flags;
-	struct nft_data		key;
-	struct nft_data		data[];
+	struct nft_set_ext	ext;
 };
 
 static bool nft_rbtree_lookup(const struct nft_set *set,
@@ -45,7 +43,7 @@ static bool nft_rbtree_lookup(const struct nft_set *set,
 	while (parent != NULL) {
 		rbe = rb_entry(parent, struct nft_rbtree_elem, node);
 
-		d = nft_data_cmp(&rbe->key, key, set->klen);
+		d = nft_data_cmp(nft_set_ext_key(&rbe->ext), key, set->klen);
 		if (d < 0) {
 			parent = parent->rb_left;
 			interval = rbe;
@@ -53,10 +51,12 @@ static bool nft_rbtree_lookup(const struct nft_set *set,
 			parent = parent->rb_right;
 		else {
 found:
-			if (rbe->flags & NFT_SET_ELEM_INTERVAL_END)
+			if (nft_set_ext_exists(&rbe->ext, NFT_SET_EXT_FLAGS) &&
+			    *nft_set_ext_flags(&rbe->ext) &
+			    NFT_SET_ELEM_INTERVAL_END)
 				goto out;
 			if (set->flags & NFT_SET_MAP)
-				nft_data_copy(data, rbe->data);
+				nft_data_copy(data, nft_set_ext_data(&rbe->ext));
 
 			spin_unlock_bh(&nft_rbtree_lock);
 			return true;
@@ -75,10 +75,10 @@ out:
 static void nft_rbtree_elem_destroy(const struct nft_set *set,
 				    struct nft_rbtree_elem *rbe)
 {
-	nft_data_uninit(&rbe->key, NFT_DATA_VALUE);
+	nft_data_uninit(nft_set_ext_key(&rbe->ext), NFT_DATA_VALUE);
 	if (set->flags & NFT_SET_MAP &&
-	    !(rbe->flags & NFT_SET_ELEM_INTERVAL_END))
-		nft_data_uninit(rbe->data, set->dtype);
+	    nft_set_ext_exists(&rbe->ext, NFT_SET_EXT_DATA))
+		nft_data_uninit(nft_set_ext_data(&rbe->ext), set->dtype);
 
 	kfree(rbe);
 }
@@ -96,7 +96,9 @@ static int __nft_rbtree_insert(const struct nft_set *set,
 	while (*p != NULL) {
 		parent = *p;
 		rbe = rb_entry(parent, struct nft_rbtree_elem, node);
-		d = nft_data_cmp(&rbe->key, &new->key, set->klen);
+		d = nft_data_cmp(nft_set_ext_key(&rbe->ext),
+				 nft_set_ext_key(&new->ext),
+				 set->klen);
 		if (d < 0)
 			p = &parent->rb_left;
 		else if (d > 0)
@@ -112,31 +114,13 @@ static int __nft_rbtree_insert(const struct nft_set *set,
 static int nft_rbtree_insert(const struct nft_set *set,
 			     const struct nft_set_elem *elem)
 {
-	struct nft_rbtree_elem *rbe;
-	unsigned int size;
+	struct nft_rbtree_elem *rbe = elem->priv;
 	int err;
 
-	size = sizeof(*rbe);
-	if (set->flags & NFT_SET_MAP &&
-	    !(elem->flags & NFT_SET_ELEM_INTERVAL_END))
-		size += sizeof(rbe->data[0]);
-
-	rbe = kzalloc(size, GFP_KERNEL);
-	if (rbe == NULL)
-		return -ENOMEM;
-
-	rbe->flags = elem->flags;
-	nft_data_copy(&rbe->key, &elem->key);
-	if (set->flags & NFT_SET_MAP &&
-	    !(rbe->flags & NFT_SET_ELEM_INTERVAL_END))
-		nft_data_copy(rbe->data, &elem->data);
-
 	spin_lock_bh(&nft_rbtree_lock);
 	err = __nft_rbtree_insert(set, rbe);
-	if (err < 0)
-		kfree(rbe);
-
 	spin_unlock_bh(&nft_rbtree_lock);
+
 	return err;
 }
 
@@ -162,17 +146,15 @@ static int nft_rbtree_get(const struct nft_set *set, struct nft_set_elem *elem)
 	while (parent != NULL) {
 		rbe = rb_entry(parent, struct nft_rbtree_elem, node);
 
-		d = nft_data_cmp(&rbe->key, &elem->key, set->klen);
+		d = nft_data_cmp(nft_set_ext_key(&rbe->ext), &elem->key,
+				 set->klen);
 		if (d < 0)
 			parent = parent->rb_left;
 		else if (d > 0)
 			parent = parent->rb_right;
 		else {
 			elem->cookie = rbe;
-			if (set->flags & NFT_SET_MAP &&
-			    !(rbe->flags & NFT_SET_ELEM_INTERVAL_END))
-				nft_data_copy(&elem->data, rbe->data);
-			elem->flags = rbe->flags;
+			elem->priv   = rbe;
 			return 0;
 		}
 	}
@@ -184,7 +166,7 @@ static void nft_rbtree_walk(const struct nft_ctx *ctx,
 			    struct nft_set_iter *iter)
 {
 	const struct nft_rbtree *priv = nft_set_priv(set);
-	const struct nft_rbtree_elem *rbe;
+	struct nft_rbtree_elem *rbe;
 	struct nft_set_elem elem;
 	struct rb_node *node;
 
@@ -194,11 +176,7 @@ static void nft_rbtree_walk(const struct nft_ctx *ctx,
 			goto cont;
 
 		rbe = rb_entry(node, struct nft_rbtree_elem, node);
-		nft_data_copy(&elem.key, &rbe->key);
-		if (set->flags & NFT_SET_MAP &&
-		    !(rbe->flags & NFT_SET_ELEM_INTERVAL_END))
-			nft_data_copy(&elem.data, rbe->data);
-		elem.flags = rbe->flags;
+		elem.priv = rbe;
 
 		iter->err = iter->fn(ctx, set, iter, &elem);
 		if (iter->err < 0) {
@@ -245,9 +223,6 @@ static bool nft_rbtree_estimate(const struct nft_set_desc *desc, u32 features,
 	unsigned int nsize;
 
 	nsize = sizeof(struct nft_rbtree_elem);
-	if (features & NFT_SET_MAP)
-		nsize += FIELD_SIZEOF(struct nft_rbtree_elem, data[0]);
-
 	if (desc->size)
 		est->size = sizeof(struct nft_rbtree) + desc->size * nsize;
 	else
@@ -260,6 +235,7 @@ static bool nft_rbtree_estimate(const struct nft_set_desc *desc, u32 features,
 
 static struct nft_set_ops nft_rbtree_ops __read_mostly = {
 	.privsize	= nft_rbtree_privsize,
+	.elemsize	= offsetof(struct nft_rbtree_elem, ext),
 	.estimate	= nft_rbtree_estimate,
 	.init		= nft_rbtree_init,
 	.destroy	= nft_rbtree_destroy,