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, 10 insertions, 4 deletions

diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
index 038f8a67ca1f..ef3457c1cb62 100644
--- a/include/net/netfilter/nf_tables.h
+++ b/include/net/netfilter/nf_tables.h
@@ -140,8 +140,7 @@ struct nft_userdata {
  *
  *	@cookie: implementation specific element cookie
  *	@key: element key
- *	@data: element data (maps only)
- *	@flags: element flags (end of interval)
+ *	@priv: element private data and extensions
  *
  *	The cookie can be used to store a handle to the element for subsequent
  *	removal.
@@ -149,8 +148,7 @@ struct nft_userdata {
 struct nft_set_elem {
 	void			*cookie;
 	struct nft_data		key;
-	struct nft_data		data;
-	u32			flags;
+	void			*priv;
 };
 
 struct nft_set;
@@ -214,6 +212,7 @@ struct nft_set_estimate {
  *	@destroy: destroy private data of set instance
  *	@list: nf_tables_set_ops list node
  *	@owner: module reference
+ *	@elemsize: element private size
  *	@features: features supported by the implementation
  */
 struct nft_set_ops {
@@ -241,6 +240,7 @@ struct nft_set_ops {
 
 	struct list_head		list;
 	struct module			*owner;
+	unsigned int			elemsize;
 	u32				features;
 };
 
@@ -417,6 +417,12 @@ static inline u8 *nft_set_ext_flags(const struct nft_set_ext *ext)
 	return nft_set_ext(ext, NFT_SET_EXT_FLAGS);
 }
 
+static inline struct nft_set_ext *nft_set_elem_ext(const struct nft_set *set,
+						   void *elem)
+{
+	return elem + set->ops->elemsize;
+}
+
 /**
  *	struct nft_expr_type - nf_tables expression type
  *