* [PATCH nf-next 2/5] netfilter: nft_set: remove one argument from lookup and update functions
2025-07-01 18:52 [PATCH nf-next 0/5] netfilter: nft_set updates Florian Westphal
2025-07-01 18:52 ` [PATCH nf-next 1/5] netfilter: nft_set_pipapo: remove unused arguments Florian Westphal
@ 2025-07-01 18:52 ` Florian Westphal
2025-07-03 20:10 ` kernel test robot
2025-07-01 18:52 ` [PATCH nf-next 3/5] netfilter: nft_set: remove indirection from update API call Florian Westphal
` (2 subsequent siblings)
4 siblings, 1 reply; 11+ messages in thread
From: Florian Westphal @ 2025-07-01 18:52 UTC (permalink / raw)
To: netfilter-devel; +Cc: sbrivio, Florian Westphal
Return the extension pointer instead of passing it as a function
argument to be filled in by the callee.
As-is, whenever false is returned, the extension pointer is not used.
For all set types, when true is returned, the extension pointer was set
to the matching element.
Only exception: nft_set_bitmap doesn't support extensions.
Return a pointer to a static const empty element extension container.
return false -> return NULL
return true -> return the elements' extension pointer.
This saves one function argument.
Signed-off-by: Florian Westphal <fw@strlen.de>
---
include/net/netfilter/nf_tables.h | 10 ++---
include/net/netfilter/nf_tables_core.h | 47 ++++++++++++----------
net/netfilter/nft_dynset.c | 5 ++-
net/netfilter/nft_lookup.c | 27 ++++++-------
net/netfilter/nft_objref.c | 5 +--
net/netfilter/nft_set_bitmap.c | 11 ++++--
net/netfilter/nft_set_hash.c | 54 ++++++++++++--------------
net/netfilter/nft_set_pipapo.c | 19 +++++----
net/netfilter/nft_set_pipapo_avx2.c | 25 ++++++------
net/netfilter/nft_set_rbtree.c | 40 +++++++++----------
10 files changed, 126 insertions(+), 117 deletions(-)
diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
index e4d8e451e935..2da886716adc 100644
--- a/include/net/netfilter/nf_tables.h
+++ b/include/net/netfilter/nf_tables.h
@@ -459,19 +459,17 @@ struct nft_set_ext;
* control plane functions.
*/
struct nft_set_ops {
- bool (*lookup)(const struct net *net,
+ const struct nft_set_ext * (*lookup)(const struct net *net,
const struct nft_set *set,
- const u32 *key,
- const struct nft_set_ext **ext);
- bool (*update)(struct nft_set *set,
+ const u32 *key);
+ const struct nft_set_ext * (*update)(struct nft_set *set,
const u32 *key,
struct nft_elem_priv *
(*new)(struct nft_set *,
const struct nft_expr *,
struct nft_regs *),
const struct nft_expr *expr,
- struct nft_regs *regs,
- const struct nft_set_ext **ext);
+ struct nft_regs *regs);
bool (*delete)(const struct nft_set *set,
const u32 *key);
diff --git a/include/net/netfilter/nf_tables_core.h b/include/net/netfilter/nf_tables_core.h
index 03b6165756fc..6a52fb97b844 100644
--- a/include/net/netfilter/nf_tables_core.h
+++ b/include/net/netfilter/nf_tables_core.h
@@ -94,34 +94,41 @@ extern const struct nft_set_type nft_set_pipapo_type;
extern const struct nft_set_type nft_set_pipapo_avx2_type;
#ifdef CONFIG_MITIGATION_RETPOLINE
-bool nft_rhash_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext);
-bool nft_rbtree_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext);
-bool nft_bitmap_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext);
-bool nft_hash_lookup_fast(const struct net *net,
- const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext);
-bool nft_hash_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext);
-bool nft_set_do_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext);
+const struct nft_set_ext *
+nft_rhash_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key);
+const struct nft_set_ext *
+nft_rbtree_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key);
+const struct nft_set_ext *
+nft_bitmap_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key);
+const struct nft_set_ext *
+nft_hash_lookup_fast(const struct net *net, const struct nft_set *set,
+ const u32 *key);
+const struct nft_set_ext *
+nft_hash_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key);
+const struct nft_set_ext *
+nft_set_do_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key);
#else
-static inline bool
+static inline const struct nft_set_ext *
nft_set_do_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext)
+ const u32 *key)
{
- return set->ops->lookup(net, set, key, ext);
+ return set->ops->lookup(net, set, key);
}
#endif
/* called from nft_pipapo_avx2.c */
-bool nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext);
+const struct nft_set_ext *
+nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key);
/* called from nft_set_pipapo.c */
-bool nft_pipapo_avx2_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext);
+const struct nft_set_ext *
+nft_pipapo_avx2_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key);
void nft_counter_init_seqcount(void);
diff --git a/net/netfilter/nft_dynset.c b/net/netfilter/nft_dynset.c
index 88922e0e8e83..e24493d9e776 100644
--- a/net/netfilter/nft_dynset.c
+++ b/net/netfilter/nft_dynset.c
@@ -91,8 +91,9 @@ void nft_dynset_eval(const struct nft_expr *expr,
return;
}
- if (set->ops->update(set, ®s->data[priv->sreg_key], nft_dynset_new,
- expr, regs, &ext)) {
+ ext = set->ops->update(set, ®s->data[priv->sreg_key], nft_dynset_new,
+ expr, regs);
+ if (ext) {
if (priv->op == NFT_DYNSET_OP_UPDATE &&
nft_set_ext_exists(ext, NFT_SET_EXT_TIMEOUT) &&
READ_ONCE(nft_set_ext_timeout(ext)->timeout) != 0) {
diff --git a/net/netfilter/nft_lookup.c b/net/netfilter/nft_lookup.c
index 63ef832b8aa7..40c602ffbcba 100644
--- a/net/netfilter/nft_lookup.c
+++ b/net/netfilter/nft_lookup.c
@@ -25,32 +25,33 @@ struct nft_lookup {
};
#ifdef CONFIG_MITIGATION_RETPOLINE
-bool nft_set_do_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext)
+const struct nft_set_ext *
+nft_set_do_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key)
{
if (set->ops == &nft_set_hash_fast_type.ops)
- return nft_hash_lookup_fast(net, set, key, ext);
+ return nft_hash_lookup_fast(net, set, key);
if (set->ops == &nft_set_hash_type.ops)
- return nft_hash_lookup(net, set, key, ext);
+ return nft_hash_lookup(net, set, key);
if (set->ops == &nft_set_rhash_type.ops)
- return nft_rhash_lookup(net, set, key, ext);
+ return nft_rhash_lookup(net, set, key);
if (set->ops == &nft_set_bitmap_type.ops)
- return nft_bitmap_lookup(net, set, key, ext);
+ return nft_bitmap_lookup(net, set, key);
if (set->ops == &nft_set_pipapo_type.ops)
- return nft_pipapo_lookup(net, set, key, ext);
+ return nft_pipapo_lookup(net, set, key);
#if defined(CONFIG_X86_64) && !defined(CONFIG_UML)
if (set->ops == &nft_set_pipapo_avx2_type.ops)
- return nft_pipapo_avx2_lookup(net, set, key, ext);
+ return nft_pipapo_avx2_lookup(net, set, key);
#endif
if (set->ops == &nft_set_rbtree_type.ops)
- return nft_rbtree_lookup(net, set, key, ext);
+ return nft_rbtree_lookup(net, set, key);
WARN_ON_ONCE(1);
- return set->ops->lookup(net, set, key, ext);
+ return set->ops->lookup(net, set, key);
}
EXPORT_SYMBOL_GPL(nft_set_do_lookup);
#endif
@@ -61,12 +62,12 @@ void nft_lookup_eval(const struct nft_expr *expr,
{
const struct nft_lookup *priv = nft_expr_priv(expr);
const struct nft_set *set = priv->set;
- const struct nft_set_ext *ext = NULL;
const struct net *net = nft_net(pkt);
+ const struct nft_set_ext *ext;
bool found;
- found = nft_set_do_lookup(net, set, ®s->data[priv->sreg], &ext) ^
- priv->invert;
+ ext = nft_set_do_lookup(net, set, ®s->data[priv->sreg]);
+ found = !!ext ^ priv->invert;
if (!found) {
ext = nft_set_catchall_lookup(net, set);
if (!ext) {
diff --git a/net/netfilter/nft_objref.c b/net/netfilter/nft_objref.c
index 09da7a3f9f96..8ee66a86c3bc 100644
--- a/net/netfilter/nft_objref.c
+++ b/net/netfilter/nft_objref.c
@@ -111,10 +111,9 @@ void nft_objref_map_eval(const struct nft_expr *expr,
struct net *net = nft_net(pkt);
const struct nft_set_ext *ext;
struct nft_object *obj;
- bool found;
- found = nft_set_do_lookup(net, set, ®s->data[priv->sreg], &ext);
- if (!found) {
+ ext = nft_set_do_lookup(net, set, ®s->data[priv->sreg]);
+ if (!ext) {
ext = nft_set_catchall_lookup(net, set);
if (!ext) {
regs->verdict.code = NFT_BREAK;
diff --git a/net/netfilter/nft_set_bitmap.c b/net/netfilter/nft_set_bitmap.c
index 12390d2e994f..c24c922f895d 100644
--- a/net/netfilter/nft_set_bitmap.c
+++ b/net/netfilter/nft_set_bitmap.c
@@ -75,16 +75,21 @@ nft_bitmap_active(const u8 *bitmap, u32 idx, u32 off, u8 genmask)
}
INDIRECT_CALLABLE_SCOPE
-bool nft_bitmap_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext)
+const struct nft_set_ext *
+nft_bitmap_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key)
{
const struct nft_bitmap *priv = nft_set_priv(set);
+ static const struct nft_set_ext found;
u8 genmask = nft_genmask_cur(net);
u32 idx, off;
nft_bitmap_location(set, key, &idx, &off);
- return nft_bitmap_active(priv->bitmap, idx, off, genmask);
+ if (nft_bitmap_active(priv->bitmap, idx, off, genmask))
+ return &found;
+
+ return NULL;
}
static struct nft_bitmap_elem *
diff --git a/net/netfilter/nft_set_hash.c b/net/netfilter/nft_set_hash.c
index abb0c8ec6371..9903c737c9f0 100644
--- a/net/netfilter/nft_set_hash.c
+++ b/net/netfilter/nft_set_hash.c
@@ -81,8 +81,9 @@ static const struct rhashtable_params nft_rhash_params = {
};
INDIRECT_CALLABLE_SCOPE
-bool nft_rhash_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext)
+const struct nft_set_ext *
+nft_rhash_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key)
{
struct nft_rhash *priv = nft_set_priv(set);
const struct nft_rhash_elem *he;
@@ -95,9 +96,9 @@ bool nft_rhash_lookup(const struct net *net, const struct nft_set *set,
he = rhashtable_lookup(&priv->ht, &arg, nft_rhash_params);
if (he != NULL)
- *ext = &he->ext;
+ return &he->ext;
- return !!he;
+ return NULL;
}
static struct nft_elem_priv *
@@ -120,14 +121,11 @@ nft_rhash_get(const struct net *net, const struct nft_set *set,
return ERR_PTR(-ENOENT);
}
-static bool nft_rhash_update(struct nft_set *set, const u32 *key,
- struct nft_elem_priv *
- (*new)(struct nft_set *,
- const struct nft_expr *,
- struct nft_regs *regs),
- const struct nft_expr *expr,
- struct nft_regs *regs,
- const struct nft_set_ext **ext)
+static const struct nft_set_ext *
+nft_rhash_update(struct nft_set *set, const u32 *key,
+ struct nft_elem_priv *(*new)(struct nft_set *, const struct nft_expr *,
+ struct nft_regs *regs),
+ const struct nft_expr *expr, struct nft_regs *regs)
{
struct nft_rhash *priv = nft_set_priv(set);
struct nft_rhash_elem *he, *prev;
@@ -161,14 +159,13 @@ static bool nft_rhash_update(struct nft_set *set, const u32 *key,
}
out:
- *ext = &he->ext;
- return true;
+ return &he->ext;
err2:
nft_set_elem_destroy(set, &he->priv, true);
atomic_dec(&set->nelems);
err1:
- return false;
+ return NULL;
}
static int nft_rhash_insert(const struct net *net, const struct nft_set *set,
@@ -507,8 +504,9 @@ struct nft_hash_elem {
};
INDIRECT_CALLABLE_SCOPE
-bool nft_hash_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext)
+const struct nft_set_ext *
+nft_hash_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key)
{
struct nft_hash *priv = nft_set_priv(set);
u8 genmask = nft_genmask_cur(net);
@@ -519,12 +517,10 @@ bool nft_hash_lookup(const struct net *net, const struct nft_set *set,
hash = reciprocal_scale(hash, priv->buckets);
hlist_for_each_entry_rcu(he, &priv->table[hash], node) {
if (!memcmp(nft_set_ext_key(&he->ext), key, set->klen) &&
- nft_set_elem_active(&he->ext, genmask)) {
- *ext = &he->ext;
- return true;
- }
+ nft_set_elem_active(&he->ext, genmask))
+ return &he->ext;
}
- return false;
+ return NULL;
}
static struct nft_elem_priv *
@@ -547,9 +543,9 @@ nft_hash_get(const struct net *net, const struct nft_set *set,
}
INDIRECT_CALLABLE_SCOPE
-bool nft_hash_lookup_fast(const struct net *net,
- const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext)
+const struct nft_set_ext *
+nft_hash_lookup_fast(const struct net *net, const struct nft_set *set,
+ const u32 *key)
{
struct nft_hash *priv = nft_set_priv(set);
u8 genmask = nft_genmask_cur(net);
@@ -562,12 +558,10 @@ bool nft_hash_lookup_fast(const struct net *net,
hlist_for_each_entry_rcu(he, &priv->table[hash], node) {
k2 = *(u32 *)nft_set_ext_key(&he->ext)->data;
if (k1 == k2 &&
- nft_set_elem_active(&he->ext, genmask)) {
- *ext = &he->ext;
- return true;
- }
+ nft_set_elem_active(&he->ext, genmask))
+ return &he->ext;
}
- return false;
+ return NULL;
}
static u32 nft_jhash(const struct nft_set *set, const struct nft_hash *priv,
diff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c
index 08fb6720673f..36a4de11995b 100644
--- a/net/netfilter/nft_set_pipapo.c
+++ b/net/netfilter/nft_set_pipapo.c
@@ -407,8 +407,9 @@ int pipapo_refill(unsigned long *map, unsigned int len, unsigned int rules,
*
* Return: true on match, false otherwise.
*/
-bool nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext)
+const struct nft_set_ext *
+nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key)
{
struct nft_pipapo *priv = nft_set_priv(set);
struct nft_pipapo_scratch *scratch;
@@ -465,13 +466,15 @@ bool nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
scratch->map_index = map_index;
local_bh_enable();
- return false;
+ return NULL;
}
if (last) {
- *ext = &f->mt[b].e->ext;
- if (unlikely(nft_set_elem_expired(*ext) ||
- !nft_set_elem_active(*ext, genmask)))
+ const struct nft_set_ext *ext;
+
+ ext = &f->mt[b].e->ext;
+ if (unlikely(nft_set_elem_expired(ext) ||
+ !nft_set_elem_active(ext, genmask)))
goto next_match;
/* Last field: we're just returning the key without
@@ -482,7 +485,7 @@ bool nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
scratch->map_index = map_index;
local_bh_enable();
- return true;
+ return ext;
}
/* Swap bitmap indices: res_map is the initial bitmap for the
@@ -497,7 +500,7 @@ bool nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
out:
local_bh_enable();
- return false;
+ return NULL;
}
/**
diff --git a/net/netfilter/nft_set_pipapo_avx2.c b/net/netfilter/nft_set_pipapo_avx2.c
index be7c16c79f71..6c441e2dc8af 100644
--- a/net/netfilter/nft_set_pipapo_avx2.c
+++ b/net/netfilter/nft_set_pipapo_avx2.c
@@ -1146,8 +1146,9 @@ static inline void pipapo_resmap_init_avx2(const struct nft_pipapo_match *m, uns
*
* Return: true on match, false otherwise.
*/
-bool nft_pipapo_avx2_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext)
+const struct nft_set_ext *
+nft_pipapo_avx2_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key)
{
struct nft_pipapo *priv = nft_set_priv(set);
struct nft_pipapo_scratch *scratch;
@@ -1155,17 +1156,18 @@ bool nft_pipapo_avx2_lookup(const struct net *net, const struct nft_set *set,
const struct nft_pipapo_match *m;
const struct nft_pipapo_field *f;
const u8 *rp = (const u8 *)key;
+ const struct nft_set_ext *ext;
unsigned long *res, *fill;
bool map_index;
- int i, ret = 0;
+ int i;
local_bh_disable();
if (unlikely(!irq_fpu_usable())) {
- bool fallback_res = nft_pipapo_lookup(net, set, key, ext);
+ ext = nft_pipapo_lookup(net, set, key);
local_bh_enable();
- return fallback_res;
+ return ext;
}
m = rcu_dereference(priv->match);
@@ -1182,7 +1184,7 @@ bool nft_pipapo_avx2_lookup(const struct net *net, const struct nft_set *set,
if (unlikely(!scratch)) {
kernel_fpu_end();
local_bh_enable();
- return false;
+ return NULL;
}
map_index = scratch->map_index;
@@ -1197,6 +1199,7 @@ bool nft_pipapo_avx2_lookup(const struct net *net, const struct nft_set *set,
next_match:
nft_pipapo_for_each_field(f, i, m) {
bool last = i == m->field_count - 1, first = !i;
+ int ret = 0;
#define NFT_SET_PIPAPO_AVX2_LOOKUP(b, n) \
(ret = nft_pipapo_avx2_lookup_##b##b_##n(res, fill, f, \
@@ -1244,10 +1247,10 @@ bool nft_pipapo_avx2_lookup(const struct net *net, const struct nft_set *set,
goto out;
if (last) {
- *ext = &f->mt[ret].e->ext;
- if (unlikely(nft_set_elem_expired(*ext) ||
- !nft_set_elem_active(*ext, genmask))) {
- ret = 0;
+ ext = &f->mt[ret].e->ext;
+ if (unlikely(nft_set_elem_expired(ext) ||
+ !nft_set_elem_active(ext, genmask))) {
+ ext = NULL;
goto next_match;
}
@@ -1264,5 +1267,5 @@ bool nft_pipapo_avx2_lookup(const struct net *net, const struct nft_set *set,
kernel_fpu_end();
local_bh_enable();
- return ret >= 0;
+ return ext;
}
diff --git a/net/netfilter/nft_set_rbtree.c b/net/netfilter/nft_set_rbtree.c
index 2e8ef16ff191..938a257c069e 100644
--- a/net/netfilter/nft_set_rbtree.c
+++ b/net/netfilter/nft_set_rbtree.c
@@ -52,9 +52,9 @@ static bool nft_rbtree_elem_expired(const struct nft_rbtree_elem *rbe)
return nft_set_elem_expired(&rbe->ext);
}
-static bool __nft_rbtree_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext,
- unsigned int seq)
+static const struct nft_set_ext *
+__nft_rbtree_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key, unsigned int seq)
{
struct nft_rbtree *priv = nft_set_priv(set);
const struct nft_rbtree_elem *rbe, *interval = NULL;
@@ -65,7 +65,7 @@ static bool __nft_rbtree_lookup(const struct net *net, const struct nft_set *set
parent = rcu_dereference_raw(priv->root.rb_node);
while (parent != NULL) {
if (read_seqcount_retry(&priv->count, seq))
- return false;
+ return NULL;
rbe = rb_entry(parent, struct nft_rbtree_elem, node);
@@ -87,50 +87,48 @@ static bool __nft_rbtree_lookup(const struct net *net, const struct nft_set *set
}
if (nft_rbtree_elem_expired(rbe))
- return false;
+ return NULL;
if (nft_rbtree_interval_end(rbe)) {
if (nft_set_is_anonymous(set))
- return false;
+ return NULL;
parent = rcu_dereference_raw(parent->rb_left);
interval = NULL;
continue;
}
- *ext = &rbe->ext;
- return true;
+ return &rbe->ext;
}
}
if (set->flags & NFT_SET_INTERVAL && interval != NULL &&
nft_set_elem_active(&interval->ext, genmask) &&
!nft_rbtree_elem_expired(interval) &&
- nft_rbtree_interval_start(interval)) {
- *ext = &interval->ext;
- return true;
- }
+ nft_rbtree_interval_start(interval))
+ return &interval->ext;
- return false;
+ return NULL;
}
INDIRECT_CALLABLE_SCOPE
-bool nft_rbtree_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key, const struct nft_set_ext **ext)
+const struct nft_set_ext *
+nft_rbtree_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key)
{
struct nft_rbtree *priv = nft_set_priv(set);
unsigned int seq = read_seqcount_begin(&priv->count);
- bool ret;
+ const struct nft_set_ext *ext;
- ret = __nft_rbtree_lookup(net, set, key, ext, seq);
- if (ret || !read_seqcount_retry(&priv->count, seq))
- return ret;
+ ext = __nft_rbtree_lookup(net, set, key, seq);
+ if (ext || !read_seqcount_retry(&priv->count, seq))
+ return ext;
read_lock_bh(&priv->lock);
seq = read_seqcount_begin(&priv->count);
- ret = __nft_rbtree_lookup(net, set, key, ext, seq);
+ ext = __nft_rbtree_lookup(net, set, key, seq);
read_unlock_bh(&priv->lock);
- return ret;
+ return ext;
}
static bool __nft_rbtree_get(const struct net *net, const struct nft_set *set,
--
2.49.0
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH nf-next 4/5] netfilter: nft_set_pipapo: merge pipapo_get/lookup
2025-07-01 18:52 [PATCH nf-next 0/5] netfilter: nft_set updates Florian Westphal
` (2 preceding siblings ...)
2025-07-01 18:52 ` [PATCH nf-next 3/5] netfilter: nft_set: remove indirection from update API call Florian Westphal
@ 2025-07-01 18:52 ` Florian Westphal
2025-07-08 6:09 ` Stefano Brivio
2025-07-01 18:52 ` [PATCH nf-next 5/5] netfilter: nft_set_pipapo: prefer kvmalloc for scratch maps Florian Westphal
4 siblings, 1 reply; 11+ messages in thread
From: Florian Westphal @ 2025-07-01 18:52 UTC (permalink / raw)
To: netfilter-devel; +Cc: sbrivio, Florian Westphal
The matching algorithm has implemented thrice:
1. data path lookup, generic version
2. data path lookup, avx2 version
3. control plane lookup
Merge 1 and 3 by refactoring pipapo_get as a common helper, then make
nft_pipapo_lookup and nft_pipapo_get both call the common helper.
Aside from the code savings this has the benefit that we no longer allocate
temporary scratch maps for each control plane get and insertion operation.
Signed-off-by: Florian Westphal <fw@strlen.de>
---
net/netfilter/nft_set_pipapo.c | 189 ++++++++++-----------------------
1 file changed, 59 insertions(+), 130 deletions(-)
diff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c
index 36a4de11995b..ebd142d8d4d4 100644
--- a/net/netfilter/nft_set_pipapo.c
+++ b/net/netfilter/nft_set_pipapo.c
@@ -397,35 +397,37 @@ int pipapo_refill(unsigned long *map, unsigned int len, unsigned int rules,
}
/**
- * nft_pipapo_lookup() - Lookup function
- * @net: Network namespace
- * @set: nftables API set representation
- * @key: nftables API element representation containing key data
- * @ext: nftables API extension pointer, filled with matching reference
+ * pipapo_get() - Get matching element reference given key data
+ * @m: storage containing the set elements
+ * @data: Key data to be matched against existing elements
+ * @genmask: If set, check that element is active in given genmask
+ * @tstamp: timestamp to check for expired elements
*
* For more details, see DOC: Theory of Operation.
*
- * Return: true on match, false otherwise.
+ * This is the main lookup function. It matches key data either against
+ * the working match set or the uncomitted copy, depending on what the
+ * caller passed to us.
+ * nft_pipapo_get (lookup from userspace/control plane) and nft_pipapo_lookup
+ * (datapath lookup) pass the active copy.
+ * The insertion path will pass the uncomitted working copy.
+ *
+ * Return: pointer to &struct nft_pipapo_elem on match, NULL otherwise.
*/
-const struct nft_set_ext *
-nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
- const u32 *key)
+static struct nft_pipapo_elem *pipapo_get(const struct nft_pipapo_match *m,
+ const u8 *data, u8 genmask,
+ u64 tstamp)
{
- struct nft_pipapo *priv = nft_set_priv(set);
struct nft_pipapo_scratch *scratch;
unsigned long *res_map, *fill_map;
- u8 genmask = nft_genmask_cur(net);
- const struct nft_pipapo_match *m;
const struct nft_pipapo_field *f;
- const u8 *rp = (const u8 *)key;
bool map_index;
int i;
local_bh_disable();
- m = rcu_dereference(priv->match);
-
- if (unlikely(!m || !*raw_cpu_ptr(m->scratch)))
+ /* XXX: fix this, prealloc and remove this check */
+ if (unlikely(!raw_cpu_ptr(m->scratch)))
goto out;
scratch = *raw_cpu_ptr(m->scratch);
@@ -445,12 +447,12 @@ nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
* packet bytes value, then AND bucket value
*/
if (likely(f->bb == 8))
- pipapo_and_field_buckets_8bit(f, res_map, rp);
+ pipapo_and_field_buckets_8bit(f, res_map, data);
else
- pipapo_and_field_buckets_4bit(f, res_map, rp);
+ pipapo_and_field_buckets_4bit(f, res_map, data);
NFT_PIPAPO_GROUP_BITS_ARE_8_OR_4;
- rp += f->groups / NFT_PIPAPO_GROUPS_PER_BYTE(f);
+ data += f->groups / NFT_PIPAPO_GROUPS_PER_BYTE(f);
/* Now populate the bitmap for the next field, unless this is
* the last field, in which case return the matched 'ext'
@@ -470,11 +472,11 @@ nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
}
if (last) {
- const struct nft_set_ext *ext;
+ struct nft_pipapo_elem *e;
- ext = &f->mt[b].e->ext;
- if (unlikely(nft_set_elem_expired(ext) ||
- !nft_set_elem_active(ext, genmask)))
+ e = f->mt[b].e;
+ if (unlikely(__nft_set_elem_expired(&e->ext, tstamp) ||
+ !nft_set_elem_active(&e->ext, genmask)))
goto next_match;
/* Last field: we're just returning the key without
@@ -484,8 +486,7 @@ nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
*/
scratch->map_index = map_index;
local_bh_enable();
-
- return ext;
+ return e;
}
/* Swap bitmap indices: res_map is the initial bitmap for the
@@ -495,7 +496,7 @@ nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
map_index = !map_index;
swap(res_map, fill_map);
- rp += NFT_PIPAPO_GROUPS_PADDING(f);
+ data += NFT_PIPAPO_GROUPS_PADDING(f);
}
out:
@@ -504,99 +505,29 @@ nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
}
/**
- * pipapo_get() - Get matching element reference given key data
- * @m: storage containing active/existing elements
- * @data: Key data to be matched against existing elements
- * @genmask: If set, check that element is active in given genmask
- * @tstamp: timestamp to check for expired elements
- * @gfp: the type of memory to allocate (see kmalloc).
+ * nft_pipapo_lookup() - Dataplane fronted for main lookup function
+ * @net: Network namespace
+ * @set: nftables API set representation
+ * @key: pointer to nft registers containing key data
*
- * This is essentially the same as the lookup function, except that it matches
- * key data against the uncommitted copy and doesn't use preallocated maps for
- * bitmap results.
+ * This function is called from the data path. It will search for
+ * an element matching the given key in the current active copy.
*
- * Return: pointer to &struct nft_pipapo_elem on match, error pointer otherwise.
+ * Return: ntables API extension pointer or NULL if no match.
*/
-static struct nft_pipapo_elem *pipapo_get(const struct nft_pipapo_match *m,
- const u8 *data, u8 genmask,
- u64 tstamp, gfp_t gfp)
+const struct nft_set_ext *
+nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key)
{
- struct nft_pipapo_elem *ret = ERR_PTR(-ENOENT);
- unsigned long *res_map, *fill_map = NULL;
- const struct nft_pipapo_field *f;
- int i;
-
- if (m->bsize_max == 0)
- return ret;
-
- res_map = kmalloc_array(m->bsize_max, sizeof(*res_map), gfp);
- if (!res_map) {
- ret = ERR_PTR(-ENOMEM);
- goto out;
- }
-
- fill_map = kcalloc(m->bsize_max, sizeof(*res_map), gfp);
- if (!fill_map) {
- ret = ERR_PTR(-ENOMEM);
- goto out;
- }
-
- pipapo_resmap_init(m, res_map);
-
- nft_pipapo_for_each_field(f, i, m) {
- bool last = i == m->field_count - 1;
- int b;
-
- /* For each bit group: select lookup table bucket depending on
- * packet bytes value, then AND bucket value
- */
- if (f->bb == 8)
- pipapo_and_field_buckets_8bit(f, res_map, data);
- else if (f->bb == 4)
- pipapo_and_field_buckets_4bit(f, res_map, data);
- else
- BUG();
-
- data += f->groups / NFT_PIPAPO_GROUPS_PER_BYTE(f);
-
- /* Now populate the bitmap for the next field, unless this is
- * the last field, in which case return the matched 'ext'
- * pointer if any.
- *
- * Now res_map contains the matching bitmap, and fill_map is the
- * bitmap for the next field.
- */
-next_match:
- b = pipapo_refill(res_map, f->bsize, f->rules, fill_map, f->mt,
- last);
- if (b < 0)
- goto out;
-
- if (last) {
- if (__nft_set_elem_expired(&f->mt[b].e->ext, tstamp))
- goto next_match;
- if ((genmask &&
- !nft_set_elem_active(&f->mt[b].e->ext, genmask)))
- goto next_match;
-
- ret = f->mt[b].e;
- goto out;
- }
-
- data += NFT_PIPAPO_GROUPS_PADDING(f);
+ struct nft_pipapo *priv = nft_set_priv(set);
+ u8 genmask = nft_genmask_cur(net);
+ const struct nft_pipapo_match *m;
+ const struct nft_pipapo_elem *e;
- /* Swap bitmap indices: fill_map will be the initial bitmap for
- * the next field (i.e. the new res_map), and res_map is
- * guaranteed to be all-zeroes at this point, ready to be filled
- * according to the next mapping table.
- */
- swap(res_map, fill_map);
- }
+ m = rcu_dereference(priv->match);
+ e = pipapo_get(m, (const u8 *)key, genmask, get_jiffies_64());
-out:
- kfree(fill_map);
- kfree(res_map);
- return ret;
+ return e ? &e->ext : NULL;
}
/**
@@ -605,6 +536,11 @@ static struct nft_pipapo_elem *pipapo_get(const struct nft_pipapo_match *m,
* @set: nftables API set representation
* @elem: nftables API element representation containing key data
* @flags: Unused
+ *
+ * This function is called from the control plane path under
+ * RCU read lock.
+ *
+ * Return: set element private pointer; ERR_PTR if no match.
*/
static struct nft_elem_priv *
nft_pipapo_get(const struct net *net, const struct nft_set *set,
@@ -615,10 +551,9 @@ nft_pipapo_get(const struct net *net, const struct nft_set *set,
struct nft_pipapo_elem *e;
e = pipapo_get(m, (const u8 *)elem->key.val.data,
- nft_genmask_cur(net), get_jiffies_64(),
- GFP_ATOMIC);
- if (IS_ERR(e))
- return ERR_CAST(e);
+ nft_genmask_cur(net), get_jiffies_64());
+ if (!e)
+ return ERR_PTR(-ENOENT);
return &e->priv;
}
@@ -1344,8 +1279,8 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,
else
end = start;
- dup = pipapo_get(m, start, genmask, tstamp, GFP_KERNEL);
- if (!IS_ERR(dup)) {
+ dup = pipapo_get(m, start, genmask, tstamp);
+ if (dup) {
/* Check if we already have the same exact entry */
const struct nft_data *dup_key, *dup_end;
@@ -1364,15 +1299,9 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,
return -ENOTEMPTY;
}
- if (PTR_ERR(dup) == -ENOENT) {
- /* Look for partially overlapping entries */
- dup = pipapo_get(m, end, nft_genmask_next(net), tstamp,
- GFP_KERNEL);
- }
-
- if (PTR_ERR(dup) != -ENOENT) {
- if (IS_ERR(dup))
- return PTR_ERR(dup);
+ /* Look for partially overlapping entries */
+ dup = pipapo_get(m, end, nft_genmask_next(net), tstamp);
+ if (dup) {
*elem_priv = &dup->priv;
return -ENOTEMPTY;
}
@@ -1914,8 +1843,8 @@ nft_pipapo_deactivate(const struct net *net, const struct nft_set *set,
return NULL;
e = pipapo_get(m, (const u8 *)elem->key.val.data,
- nft_genmask_next(net), nft_net_tstamp(net), GFP_KERNEL);
- if (IS_ERR(e))
+ nft_genmask_next(net), nft_net_tstamp(net));
+ if (!e)
return NULL;
nft_set_elem_change_active(net, set, &e->ext);
--
2.49.0
^ permalink raw reply related [flat|nested] 11+ messages in thread