diff --git a/include/net/netfilter/nf_tables_core.h b/include/net/netfilter/nf_tables_core.h
index 2656155b40697846db4b8f8f6fda49e5f242d7c3..29e7e10212678da116c24c708d8259ca68522ec0 100644
--- a/include/net/netfilter/nf_tables_core.h
+++ b/include/net/netfilter/nf_tables_core.h
@@ -74,6 +74,7 @@ extern struct nft_set_type nft_set_hash_type;
extern struct nft_set_type nft_set_hash_fast_type;
extern struct nft_set_type nft_set_rbtree_type;
extern struct nft_set_type nft_set_bitmap_type;
+extern struct nft_set_type nft_set_pipapo_type;
struct nft_expr;
struct nft_regs;
diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile
index 5e9b2eb243493307609fc5b42980786139a40e1b..3f572e5a975eb6985bbf8d2f3214bd732eea7bef 100644
--- a/net/netfilter/Makefile
+++ b/net/netfilter/Makefile
@@ -81,7 +81,8 @@ nf_tables-objs := nf_tables_core.o nf_tables_api.o nft_chain_filter.o \
nft_chain_route.o nf_tables_offload.o
nf_tables_set-objs := nf_tables_set_core.o \
- nft_set_hash.o nft_set_bitmap.o nft_set_rbtree.o
+ nft_set_hash.o nft_set_bitmap.o nft_set_rbtree.o \
+ nft_set_pipapo.o
obj-$(CONFIG_NF_TABLES) += nf_tables.o
obj-$(CONFIG_NF_TABLES_SET) += nf_tables_set.o
diff --git a/net/netfilter/nf_tables_set_core.c b/net/netfilter/nf_tables_set_core.c
index a9fce8d1005150348ef00b635a9c4d5983b7ddba..586b621007ebbf3716b60fbe23a7d59bb0a62b05 100644
--- a/net/netfilter/nf_tables_set_core.c
+++ b/net/netfilter/nf_tables_set_core.c
@@ -9,12 +9,14 @@ static int __init nf_tables_set_module_init(void)
nft_register_set(&nft_set_rhash_type);
nft_register_set(&nft_set_bitmap_type);
nft_register_set(&nft_set_rbtree_type);
+ nft_register_set(&nft_set_pipapo_type);
return 0;
}
static void __exit nf_tables_set_module_exit(void)
{
+ nft_unregister_set(&nft_set_pipapo_type);
nft_unregister_set(&nft_set_rbtree_type);
nft_unregister_set(&nft_set_bitmap_type);
nft_unregister_set(&nft_set_rhash_type);
diff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c
new file mode 100644
index 0000000000000000000000000000000000000000..f0cb1e13af5081216d799057ed5da4a314e0c4c7
--- /dev/null
+++ b/net/netfilter/nft_set_pipapo.c
@@ -0,0 +1,2102 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/* PIPAPO: PIle PAcket POlicies: set for arbitrary concatenations of ranges
+ *
+ * Copyright (c) 2019-2020 Red Hat GmbH
+ *
+ * Author: Stefano Brivio <sbrivio@redhat.com>
+ */
+
+/**
+ * DOC: Theory of Operation
+ *
+ *
+ * Problem
+ * -------
+ *
+ * Match packet bytes against entries composed of ranged or non-ranged packet
+ * field specifiers, mapping them to arbitrary references. For example:
+ *
+ * ::
+ *
+ * --- fields --->
+ * | [net],[port],[net]... => [reference]
+ * entries [net],[port],[net]... => [reference]
+ * | [net],[port],[net]... => [reference]
+ * V ...
+ *
+ * where [net] fields can be IP ranges or netmasks, and [port] fields are port
+ * ranges. Arbitrary packet fields can be matched.
+ *
+ *
+ * Algorithm Overview
+ * ------------------
+ *
+ * This algorithm is loosely inspired by [Ligatti 2010], and fundamentally
+ * relies on the consideration that every contiguous range in a space of b bits
+ * can be converted into b * 2 netmasks, from Theorem 3 in [Rottenstreich 2010],
+ * as also illustrated in Section 9 of [Kogan 2014].
+ *
+ * Classification against a number of entries, that require matching given bits
+ * of a packet field, is performed by grouping those bits in sets of arbitrary
+ * size, and classifying packet bits one group at a time.
+ *
+ * Example:
+ * to match the source port (16 bits) of a packet, we can divide those 16 bits
+ * in 4 groups of 4 bits each. Given the entry:
+ * 0000 0001 0101 1001
+ * and a packet with source port:
+ * 0000 0001 1010 1001
+ * first and second groups match, but the third doesn't. We conclude that the
+ * packet doesn't match the given entry.
+ *
+ * Translate the set to a sequence of lookup tables, one per field. Each table
+ * has two dimensions: bit groups to be matched for a single packet field, and
+ * all the possible values of said groups (buckets). Input entries are
+ * represented as one or more rules, depending on the number of composing
+ * netmasks for the given field specifier, and a group match is indicated as a
+ * set bit, with number corresponding to the rule index, in all the buckets
+ * whose value matches the entry for a given group.
+ *
+ * Rules are mapped between fields through an array of x, n pairs, with each
+ * item mapping a matched rule to one or more rules. The position of the pair in
+ * the array indicates the matched rule to be mapped to the next field, x
+ * indicates the first rule index in the next field, and n the amount of
+ * next-field rules the current rule maps to.
+ *
+ * The mapping array for the last field maps to the desired references.
+ *
+ * To match, we perform table lookups using the values of grouped packet bits,
+ * and use a sequence of bitwise operations to progressively evaluate rule
+ * matching.
+ *
+ * A stand-alone, reference implementation, also including notes about possible
+ * future optimisations, is available at:
+ * https://pipapo.lameexcu.se/
+ *
+ * Insertion
+ * ---------
+ *
+ * - For each packet field:
+ *
+ * - divide the b packet bits we want to classify into groups of size t,
+ * obtaining ceil(b / t) groups
+ *
+ * Example: match on destination IP address, with t = 4: 32 bits, 8 groups
+ * of 4 bits each
+ *
+ * - allocate a lookup table with one column ("bucket") for each possible
+ * value of a group, and with one row for each group
+ *
+ * Example: 8 groups, 2^4 buckets:
+ *
+ * ::
+ *
+ * bucket
+ * group 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
+ * 0
+ * 1
+ * 2
+ * 3
+ * 4
+ * 5
+ * 6
+ * 7
+ *
+ * - map the bits we want to classify for the current field, for a given
+ * entry, to a single rule for non-ranged and netmask set items, and to one
+ * or multiple rules for ranges. Ranges are expanded to composing netmasks
+ * by pipapo_expand().
+ *
+ * Example: 2 entries, 10.0.0.5:1024 and 192.168.1.0-192.168.2.1:2048
+ * - rule #0: 10.0.0.5
+ * - rule #1: 192.168.1.0/24
+ * - rule #2: 192.168.2.0/31
+ *
+ * - insert references to the rules in the lookup table, selecting buckets
+ * according to bit values of a rule in the given group. This is done by
+ * pipapo_insert().
+ *
+ * Example: given:
+ * - rule #0: 10.0.0.5 mapping to buckets
+ * < 0 10 0 0 0 0 0 5 >
+ * - rule #1: 192.168.1.0/24 mapping to buckets
+ * < 12 0 10 8 0 1 < 0..15 > < 0..15 > >
+ * - rule #2: 192.168.2.0/31 mapping to buckets
+ * < 12 0 10 8 0 2 0 < 0..1 > >
+ *
+ * these bits are set in the lookup table:
+ *
+ * ::
+ *
+ * bucket
+ * group 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
+ * 0 0 1,2
+ * 1 1,2 0
+ * 2 0 1,2
+ * 3 0 1,2
+ * 4 0,1,2
+ * 5 0 1 2
+ * 6 0,1,2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
+ * 7 1,2 1,2 1 1 1 0,1 1 1 1 1 1 1 1 1 1 1
+ *
+ * - if this is not the last field in the set, fill a mapping array that maps
+ * rules from the lookup table to rules belonging to the same entry in
+ * the next lookup table, done by pipapo_map().
+ *
+ * Note that as rules map to contiguous ranges of rules, given how netmask
+ * expansion and insertion is performed, &union nft_pipapo_map_bucket stores
+ * this information as pairs of first rule index, rule count.
+ *
+ * Example: 2 entries, 10.0.0.5:1024 and 192.168.1.0-192.168.2.1:2048,
+ * given lookup table #0 for field 0 (see example above):
+ *
+ * ::
+ *
+ * bucket
+ * group 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
+ * 0 0 1,2
+ * 1 1,2 0
+ * 2 0 1,2
+ * 3 0 1,2
+ * 4 0,1,2
+ * 5 0 1 2
+ * 6 0,1,2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
+ * 7 1,2 1,2 1 1 1 0,1 1 1 1 1 1 1 1 1 1 1
+ *
+ * and lookup table #1 for field 1 with:
+ * - rule #0: 1024 mapping to buckets
+ * < 0 0 4 0 >
+ * - rule #1: 2048 mapping to buckets
+ * < 0 0 5 0 >
+ *
+ * ::
+ *
+ * bucket
+ * group 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
+ * 0 0,1
+ * 1 0,1
+ * 2 0 1
+ * 3 0,1
+ *
+ * we need to map rules for 10.0.0.5 in lookup table #0 (rule #0) to 1024
+ * in lookup table #1 (rule #0) and rules for 192.168.1.0-192.168.2.1
+ * (rules #1, #2) to 2048 in lookup table #2 (rule #1):
+ *
+ * ::
+ *
+ * rule indices in current field: 0 1 2
+ * map to rules in next field: 0 1 1
+ *
+ * - if this is the last field in the set, fill a mapping array that maps
+ * rules from the last lookup table to element pointers, also done by
+ * pipapo_map().
+ *
+ * Note that, in this implementation, we have two elements (start, end) for
+ * each entry. The pointer to the end element is stored in this array, and
+ * the pointer to the start element is linked from it.
+ *
+ * Example: entry 10.0.0.5:1024 has a corresponding &struct nft_pipapo_elem
+ * pointer, 0x66, and element for 192.168.1.0-192.168.2.1:2048 is at 0x42.
+ * From the rules of lookup table #1 as mapped above:
+ *
+ * ::
+ *
+ * rule indices in last field: 0 1
+ * map to elements: 0x42 0x66
+ *
+ *
+ * Matching
+ * --------
+ *
+ * We use a result bitmap, with the size of a single lookup table bucket, to
+ * represent the matching state that applies at every algorithm step. This is
+ * done by pipapo_lookup().
+ *
+ * - For each packet field:
+ *
+ * - start with an all-ones result bitmap (res_map in pipapo_lookup())
+ *
+ * - perform a lookup into the table corresponding to the current field,
+ * for each group, and at every group, AND the current result bitmap with
+ * the value from the lookup table bucket
+ *
+ * ::
+ *
+ * Example: 192.168.1.5 < 12 0 10 8 0 1 0 5 >, with lookup table from
+ * insertion examples.
+ * Lookup table buckets are at least 3 bits wide, we'll assume 8 bits for
+ * convenience in this example. Initial result bitmap is 0xff, the steps
+ * below show the value of the result bitmap after each group is processed:
+ *
+ * bucket
+ * group 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
+ * 0 0 1,2
+ * result bitmap is now: 0xff & 0x6 [bucket 12] = 0x6
+ *
+ * 1 1,2 0
+ * result bitmap is now: 0x6 & 0x6 [bucket 0] = 0x6
+ *
+ * 2 0 1,2
+ * result bitmap is now: 0x6 & 0x6 [bucket 10] = 0x6
+ *
+ * 3 0 1,2
+ * result bitmap is now: 0x6 & 0x6 [bucket 8] = 0x6
+ *
+ * 4 0,1,2
+ * result bitmap is now: 0x6 & 0x7 [bucket 0] = 0x6
+ *
+ * 5 0 1 2
+ * result bitmap is now: 0x6 & 0x2 [bucket 1] = 0x2
+ *
+ * 6 0,1,2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
+ * result bitmap is now: 0x2 & 0x7 [bucket 0] = 0x2
+ *
+ * 7 1,2 1,2 1 1 1 0,1 1 1 1 1 1 1 1 1 1 1
+ * final result bitmap for this field is: 0x2 & 0x3 [bucket 5] = 0x2
+ *
+ * - at the next field, start with a new, all-zeroes result bitmap. For each
+ * bit set in the previous result bitmap, fill the new result bitmap
+ * (fill_map in pipapo_lookup()) with the rule indices from the
+ * corresponding buckets of the mapping field for this field, done by
+ * pipapo_refill()
+ *
+ * Example: with mapping table from insertion examples, with the current
+ * result bitmap from the previous example, 0x02:
+ *
+ * ::
+ *
+ * rule indices in current field: 0 1 2
+ * map to rules in next field: 0 1 1
+ *
+ * the new result bitmap will be 0x02: rule 1 was set, and rule 1 will be
+ * set.
+ *
+ * We can now extend this example to cover the second iteration of the step
+ * above (lookup and AND bitmap): assuming the port field is
+ * 2048 < 0 0 5 0 >, with starting result bitmap 0x2, and lookup table
+ * for "port" field from pre-computation example:
+ *
+ * ::
+ *
+ * bucket
+ * group 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
+ * 0 0,1
+ * 1 0,1
+ * 2 0 1
+ * 3 0,1
+ *
+ * operations are: 0x2 & 0x3 [bucket 0] & 0x3 [bucket 0] & 0x2 [bucket 5]
+ * & 0x3 [bucket 0], resulting bitmap is 0x2.
+ *
+ * - if this is the last field in the set, look up the value from the mapping
+ * array corresponding to the final result bitmap
+ *
+ * Example: 0x2 resulting bitmap from 192.168.1.5:2048, mapping array for
+ * last field from insertion example:
+ *
+ * ::
+ *
+ * rule indices in last field: 0 1
+ * map to elements: 0x42 0x66
+ *
+ * the matching element is at 0x42.
+ *
+ *
+ * References
+ * ----------
+ *
+ * [Ligatti 2010]
+ * A Packet-classification Algorithm for Arbitrary Bitmask Rules, with
+ * Automatic Time-space Tradeoffs
+ * Jay Ligatti, Josh Kuhn, and Chris Gage.
+ * Proceedings of the IEEE International Conference on Computer
+ * Communication Networks (ICCCN), August 2010.
+ * http://www.cse.usf.edu/~ligatti/papers/grouper-conf.pdf
+ *
+ * [Rottenstreich 2010]
+ * Worst-Case TCAM Rule Expansion
+ * Ori Rottenstreich and Isaac Keslassy.
+ * 2010 Proceedings IEEE INFOCOM, San Diego, CA, 2010.
+ * http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.212.4592&rep=rep1&type=pdf
+ *
+ * [Kogan 2014]
+ * SAX-PAC (Scalable And eXpressive PAcket Classification)
+ * Kirill Kogan, Sergey Nikolenko, Ori Rottenstreich, William Culhane,
+ * and Patrick Eugster.
+ * Proceedings of the 2014 ACM conference on SIGCOMM, August 2014.
+ * http://www.sigcomm.org/sites/default/files/ccr/papers/2014/August/2619239-2626294.pdf
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/log2.h>
+#include <linux/module.h>
+#include <linux/netlink.h>
+#include <linux/netfilter.h>
+#include <linux/netfilter/nf_tables.h>
+#include <net/netfilter/nf_tables_core.h>
+#include <uapi/linux/netfilter/nf_tables.h>
+#include <net/ipv6.h> /* For the maximum length of a field */
+#include <linux/bitmap.h>
+#include <linux/bitops.h>
+
+/* Count of concatenated fields depends on count of 32-bit nftables registers */
+#define NFT_PIPAPO_MAX_FIELDS NFT_REG32_COUNT
+
+/* Largest supported field size */
+#define NFT_PIPAPO_MAX_BYTES (sizeof(struct in6_addr))
+#define NFT_PIPAPO_MAX_BITS (NFT_PIPAPO_MAX_BYTES * BITS_PER_BYTE)
+
+/* Number of bits to be grouped together in lookup table buckets, arbitrary */
+#define NFT_PIPAPO_GROUP_BITS 4
+#define NFT_PIPAPO_GROUPS_PER_BYTE (BITS_PER_BYTE / NFT_PIPAPO_GROUP_BITS)
+
+/* Fields are padded to 32 bits in input registers */
+#define NFT_PIPAPO_GROUPS_PADDED_SIZE(x) \
+ (round_up((x) / NFT_PIPAPO_GROUPS_PER_BYTE, sizeof(u32)))
+#define NFT_PIPAPO_GROUPS_PADDING(x) \
+ (NFT_PIPAPO_GROUPS_PADDED_SIZE((x)) - (x) / NFT_PIPAPO_GROUPS_PER_BYTE)
+
+/* Number of buckets, given by 2 ^ n, with n grouped bits */
+#define NFT_PIPAPO_BUCKETS (1 << NFT_PIPAPO_GROUP_BITS)
+
+/* Each n-bit range maps to up to n * 2 rules */
+#define NFT_PIPAPO_MAP_NBITS (const_ilog2(NFT_PIPAPO_MAX_BITS * 2))
+
+/* Use the rest of mapping table buckets for rule indices, but it makes no sense
+ * to exceed 32 bits
+ */
+#if BITS_PER_LONG == 64
+#define NFT_PIPAPO_MAP_TOBITS 32
+#else
+#define NFT_PIPAPO_MAP_TOBITS (BITS_PER_LONG - NFT_PIPAPO_MAP_NBITS)
+#endif
+
+/* ...which gives us the highest allowed index for a rule */
+#define NFT_PIPAPO_RULE0_MAX ((1UL << (NFT_PIPAPO_MAP_TOBITS - 1)) \
+ - (1UL << NFT_PIPAPO_MAP_NBITS))
+
+#define nft_pipapo_for_each_field(field, index, match) \
+ for ((field) = (match)->f, (index) = 0; \
+ (index) < (match)->field_count; \
+ (index)++, (field)++)
+
+/**
+ * union nft_pipapo_map_bucket - Bucket of mapping table
+ * @to: First rule number (in next field) this rule maps to
+ * @n: Number of rules (in next field) this rule maps to
+ * @e: If there's no next field, pointer to element this rule maps to
+ */
+union nft_pipapo_map_bucket {
+ struct {
+#if BITS_PER_LONG == 64
+ static_assert(NFT_PIPAPO_MAP_TOBITS <= 32);
+ u32 to;
+
+ static_assert(NFT_PIPAPO_MAP_NBITS <= 32);
+ u32 n;
+#else
+ unsigned long to:NFT_PIPAPO_MAP_TOBITS;
+ unsigned long n:NFT_PIPAPO_MAP_NBITS;
+#endif
+ };
+ struct nft_pipapo_elem *e;
+};
+
+/**
+ * struct nft_pipapo_field - Lookup, mapping tables and related data for a field
+ * @groups: Amount of 4-bit groups
+ * @rules: Number of inserted rules
+ * @bsize: Size of each bucket in lookup table, in longs
+ * @lt: Lookup table: 'groups' rows of NFT_PIPAPO_BUCKETS buckets
+ * @mt: Mapping table: one bucket per rule
+ */
+struct nft_pipapo_field {
+ int groups;
+ unsigned long rules;
+ size_t bsize;
+ unsigned long *lt;
+ union nft_pipapo_map_bucket *mt;
+};
+
+/**
+ * struct nft_pipapo_match - Data used for lookup and matching
+ * @field_count Amount of fields in set
+ * @scratch: Preallocated per-CPU maps for partial matching results
+ * @bsize_max: Maximum lookup table bucket size of all fields, in longs
+ * @rcu Matching data is swapped on commits
+ * @f: Fields, with lookup and mapping tables
+ */
+struct nft_pipapo_match {
+ int field_count;
+ unsigned long * __percpu *scratch;
+ size_t bsize_max;
+ struct rcu_head rcu;
+ struct nft_pipapo_field f[0];
+};
+
+/* Current working bitmap index, toggled between field matches */
+static DEFINE_PER_CPU(bool, nft_pipapo_scratch_index);
+
+/**
+ * struct nft_pipapo - Representation of a set
+ * @match: Currently in-use matching data
+ * @clone: Copy where pending insertions and deletions are kept
+ * @groups: Total amount of 4-bit groups for fields in this set
+ * @width: Total bytes to be matched for one packet, including padding
+ * @dirty: Working copy has pending insertions or deletions
+ * @last_gc: Timestamp of last garbage collection run, jiffies
+ */
+struct nft_pipapo {
+ struct nft_pipapo_match __rcu *match;
+ struct nft_pipapo_match *clone;
+ int groups;
+ int width;
+ bool dirty;
+ unsigned long last_gc;
+};
+
+struct nft_pipapo_elem;
+
+/**
+ * struct nft_pipapo_elem - API-facing representation of single set element
+ * @ext: nftables API extensions
+ */
+struct nft_pipapo_elem {
+ struct nft_set_ext ext;
+};
+
+/**
+ * pipapo_refill() - For each set bit, set bits from selected mapping table item
+ * @map: Bitmap to be scanned for set bits
+ * @len: Length of bitmap in longs
+ * @rules: Number of rules in field
+ * @dst: Destination bitmap
+ * @mt: Mapping table containing bit set specifiers
+ * @match_only: Find a single bit and return, don't fill
+ *
+ * Iteration over set bits with __builtin_ctzl(): Daniel Lemire, public domain.
+ *
+ * For each bit set in map, select the bucket from mapping table with index
+ * corresponding to the position of the bit set. Use start bit and amount of
+ * bits specified in bucket to fill region in dst.
+ *
+ * Return: -1 on no match, bit position on 'match_only', 0 otherwise.
+ */
+static int pipapo_refill(unsigned long *map, int len, int rules,
+ unsigned long *dst, union nft_pipapo_map_bucket *mt,
+ bool match_only)
+{
+ unsigned long bitset;
+ int k, ret = -1;
+
+ for (k = 0; k < len; k++) {
+ bitset = map[k];
+ while (bitset) {
+ unsigned long t = bitset & -bitset;
+ int r = __builtin_ctzl(bitset);
+ int i = k * BITS_PER_LONG + r;
+
+ if (unlikely(i >= rules)) {
+ map[k] = 0;
+ return -1;
+ }
+
+ if (unlikely(match_only)) {
+ bitmap_clear(map, i, 1);
+ return i;
+ }
+
+ ret = 0;
+
+ bitmap_set(dst, mt[i].to, mt[i].n);
+
+ bitset ^= t;
+ }
+ map[k] = 0;
+ }
+
+ return ret;
+}
+
+/**
+ * nft_pipapo_lookup() - Lookup function
+ * @net: Network namespace
+ * @set: nftables API set representation
+ * @elem: nftables API element representation containing key data
+ * @ext: nftables API extension pointer, filled with matching reference
+ *
+ * For more details, see DOC: Theory of Operation.
+ *
+ * Return: true on match, false otherwise.
+ */
+static bool nft_pipapo_lookup(const struct net *net, const struct nft_set *set,
+ const u32 *key, const struct nft_set_ext **ext)
+{
+ struct nft_pipapo *priv = nft_set_priv(set);
+ unsigned long *res_map, *fill_map;
+ u8 genmask = nft_genmask_cur(net);
+ const u8 *rp = (const u8 *)key;
+ struct nft_pipapo_match *m;
+ struct nft_pipapo_field *f;
+ bool map_index;
+ int i;
+
+ local_bh_disable();
+
+ map_index = raw_cpu_read(nft_pipapo_scratch_index);
+
+ m = rcu_dereference(priv->match);
+
+ if (unlikely(!m || !*raw_cpu_ptr(m->scratch)))
+ goto out;
+
+ res_map = *raw_cpu_ptr(m->scratch) + (map_index ? m->bsize_max : 0);
+ fill_map = *raw_cpu_ptr(m->scratch) + (map_index ? 0 : m->bsize_max);
+
+ memset(res_map, 0xff, m->bsize_max * sizeof(*res_map));
+
+ nft_pipapo_for_each_field(f, i, m) {
+ bool last = i == m->field_count - 1;
+ unsigned long *lt = f->lt;
+ int b, group;
+
+ /* For each 4-bit group: select lookup table bucket depending on
+ * packet bytes value, then AND bucket value
+ */
+ for (group = 0; group < f->groups; group += 2) {
+ u8 v;
+
+ v = *rp >> 4;
+ __bitmap_and(res_map, res_map, lt + v * f->bsize,
+ f->bsize * BITS_PER_LONG);
+ lt += f->bsize * NFT_PIPAPO_BUCKETS;
+
+ v = *rp & 0x0f;
+ rp++;
+ __bitmap_and(res_map, res_map, lt + v * f->bsize,
+ f->bsize * BITS_PER_LONG);
+ lt += f->bsize * NFT_PIPAPO_BUCKETS;
+ }
+
+ /* 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) {
+ raw_cpu_write(nft_pipapo_scratch_index, map_index);
+ local_bh_enable();
+
+ return false;
+ }
+
+ if (last) {
+ *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
+ * filling the initial bitmap for the next field, so the
+ * current inactive bitmap is clean and can be reused as
+ * *next* bitmap (not initial) for the next packet.
+ */
+ raw_cpu_write(nft_pipapo_scratch_index, map_index);
+ local_bh_enable();
+
+ return true;
+ }
+
+ /* Swap bitmap indices: res_map is the initial bitmap for the
+ * next field, and fill_map is guaranteed to be all-zeroes at
+ * this point.
+ */
+ map_index = !map_index;
+ swap(res_map, fill_map);
+
+ rp += NFT_PIPAPO_GROUPS_PADDING(f->groups);
+ }
+
+out:
+ local_bh_enable();
+ return false;
+}
+
+/**
+ * pipapo_get() - Get matching element reference given key data
+ * @net: Network namespace
+ * @set: nftables API set representation
+ * @data: Key data to be matched against existing elements
+ * @genmask: If set, check that element is active in given genmask
+ *
+ * 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.
+ *
+ * Return: pointer to &struct nft_pipapo_elem on match, error pointer otherwise.
+ */
+static struct nft_pipapo_elem *pipapo_get(const struct net *net,
+ const struct nft_set *set,
+ const u8 *data, u8 genmask)
+{
+ struct nft_pipapo_elem *ret = ERR_PTR(-ENOENT);
+ struct nft_pipapo *priv = nft_set_priv(set);
+ struct nft_pipapo_match *m = priv->clone;
+ unsigned long *res_map, *fill_map = NULL;
+ struct nft_pipapo_field *f;
+ int i;
+
+ res_map = kmalloc_array(m->bsize_max, sizeof(*res_map), GFP_ATOMIC);
+ if (!res_map) {
+ ret = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
+ fill_map = kcalloc(m->bsize_max, sizeof(*res_map), GFP_ATOMIC);
+ if (!fill_map) {
+ ret = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
+ memset(res_map, 0xff, m->bsize_max * sizeof(*res_map));
+
+ nft_pipapo_for_each_field(f, i, m) {
+ bool last = i == m->field_count - 1;
+ unsigned long *lt = f->lt;
+ int b, group;
+
+ /* For each 4-bit group: select lookup table bucket depending on
+ * packet bytes value, then AND bucket value
+ */
+ for (group = 0; group < f->groups; group++) {
+ u8 v;
+
+ if (group % 2) {
+ v = *data & 0x0f;
+ data++;
+ } else {
+ v = *data >> 4;
+ }
+ __bitmap_and(res_map, res_map, lt + v * f->bsize,
+ f->bsize * BITS_PER_LONG);
+
+ lt += f->bsize * NFT_PIPAPO_BUCKETS;
+ }
+
+ /* 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) ||
+ (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->groups);
+
+ /* 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);
+ }
+
+out:
+ kfree(fill_map);
+ kfree(res_map);
+ return ret;
+}
+
+/**
+ * nft_pipapo_get() - Get matching element reference given key data
+ * @net: Network namespace
+ * @set: nftables API set representation
+ * @elem: nftables API element representation containing key data
+ * @flags: Unused
+ */
+void *nft_pipapo_get(const struct net *net, const struct nft_set *set,
+ const struct nft_set_elem *elem, unsigned int flags)
+{
+ return pipapo_get(net, set, (const u8 *)elem->key.val.data,
+ nft_genmask_cur(net));
+}
+
+/**
+ * pipapo_resize() - Resize lookup or mapping table, or both
+ * @f: Field containing lookup and mapping tables
+ * @old_rules: Previous amount of rules in field
+ * @rules: New amount of rules
+ *
+ * Increase, decrease or maintain tables size depending on new amount of rules,
+ * and copy data over. In case the new size is smaller, throw away data for
+ * highest-numbered rules.
+ *
+ * Return: 0 on success, -ENOMEM on allocation failure.
+ */
+static int pipapo_resize(struct nft_pipapo_field *f, int old_rules, int rules)
+{
+ long *new_lt = NULL, *new_p, *old_lt = f->lt, *old_p;
+ union nft_pipapo_map_bucket *new_mt, *old_mt = f->mt;
+ size_t new_bucket_size, copy;
+ int group, bucket;
+
+ new_bucket_size = DIV_ROUND_UP(rules, BITS_PER_LONG);
+
+ if (new_bucket_size == f->bsize)
+ goto mt;
+
+ if (new_bucket_size > f->bsize)
+ copy = f->bsize;
+ else
+ copy = new_bucket_size;
+
+ new_lt = kvzalloc(f->groups * NFT_PIPAPO_BUCKETS * new_bucket_size *
+ sizeof(*new_lt), GFP_KERNEL);
+ if (!new_lt)
+ return -ENOMEM;
+
+ new_p = new_lt;
+ old_p = old_lt;
+ for (group = 0; group < f->groups; group++) {
+ for (bucket = 0; bucket < NFT_PIPAPO_BUCKETS; bucket++) {
+ memcpy(new_p, old_p, copy * sizeof(*new_p));
+ new_p += copy;
+ old_p += copy;
+
+ if (new_bucket_size > f->bsize)
+ new_p += new_bucket_size - f->bsize;
+ else
+ old_p += f->bsize - new_bucket_size;
+ }
+ }
+
+mt:
+ new_mt = kvmalloc(rules * sizeof(*new_mt), GFP_KERNEL);
+ if (!new_mt) {
+ kvfree(new_lt);
+ return -ENOMEM;
+ }
+
+ memcpy(new_mt, f->mt, min(old_rules, rules) * sizeof(*new_mt));
+ if (rules > old_rules) {
+ memset(new_mt + old_rules, 0,
+ (rules - old_rules) * sizeof(*new_mt));
+ }
+
+ if (new_lt) {
+ f->bsize = new_bucket_size;
+ f->lt = new_lt;
+ kvfree(old_lt);
+ }
+
+ f->mt = new_mt;
+ kvfree(old_mt);
+
+ return 0;
+}
+
+/**
+ * pipapo_bucket_set() - Set rule bit in bucket given group and group value
+ * @f: Field containing lookup table
+ * @rule: Rule index
+ * @group: Group index
+ * @v: Value of bit group
+ */
+static void pipapo_bucket_set(struct nft_pipapo_field *f, int rule, int group,
+ int v)
+{
+ unsigned long *pos;
+
+ pos = f->lt + f->bsize * NFT_PIPAPO_BUCKETS * group;
+ pos += f->bsize * v;
+
+ __set_bit(rule, pos);
+}
+
+/**
+ * pipapo_insert() - Insert new rule in field given input key and mask length
+ * @f: Field containing lookup table
+ * @k: Input key for classification, without nftables padding
+ * @mask_bits: Length of mask; matches field length for non-ranged entry
+ *
+ * Insert a new rule reference in lookup buckets corresponding to k and
+ * mask_bits.
+ *
+ * Return: 1 on success (one rule inserted), negative error code on failure.
+ */
+static int pipapo_insert(struct nft_pipapo_field *f, const uint8_t *k,
+ int mask_bits)
+{
+ int rule = f->rules++, group, ret;
+
+ ret = pipapo_resize(f, f->rules - 1, f->rules);
+ if (ret)
+ return ret;
+
+ for (group = 0; group < f->groups; group++) {
+ int i, v;
+ u8 mask;
+
+ if (group % 2)
+ v = k[group / 2] & 0x0f;
+ else
+ v = k[group / 2] >> 4;
+
+ if (mask_bits >= (group + 1) * 4) {
+ /* Not masked */
+ pipapo_bucket_set(f, rule, group, v);
+ } else if (mask_bits <= group * 4) {
+ /* Completely masked */
+ for (i = 0; i < NFT_PIPAPO_BUCKETS; i++)
+ pipapo_bucket_set(f, rule, group, i);
+ } else {
+ /* The mask limit falls on this group */
+ mask = 0x0f >> (mask_bits - group * 4);
+ for (i = 0; i < NFT_PIPAPO_BUCKETS; i++) {
+ if ((i & ~mask) == (v & ~mask))
+ pipapo_bucket_set(f, rule, group, i);
+ }
+ }
+ }
+
+ return 1;
+}
+
+/**
+ * pipapo_step_diff() - Check if setting @step bit in netmask would change it
+ * @base: Mask we are expanding
+ * @step: Step bit for given expansion step
+ * @len: Total length of mask space (set and unset bits), bytes
+ *
+ * Convenience function for mask expansion.
+ *
+ * Return: true if step bit changes mask (i.e. isn't set), false otherwise.
+ */
+static bool pipapo_step_diff(u8 *base, int step, int len)
+{
+ /* Network order, byte-addressed */
+#ifdef __BIG_ENDIAN__
+ return !(BIT(step % BITS_PER_BYTE) & base[step / BITS_PER_BYTE]);
+#else
+ return !(BIT(step % BITS_PER_BYTE) &
+ base[len - 1 - step / BITS_PER_BYTE]);
+#endif
+}
+
+/**
+ * pipapo_step_after_end() - Check if mask exceeds range end with given step
+ * @base: Mask we are expanding
+ * @end: End of range
+ * @step: Step bit for given expansion step, highest bit to be set
+ * @len: Total length of mask space (set and unset bits), bytes
+ *
+ * Convenience function for mask expansion.
+ *
+ * Return: true if mask exceeds range setting step bits, false otherwise.
+ */
+static bool pipapo_step_after_end(const u8 *base, const u8 *end, int step,
+ int len)
+{
+ u8 tmp[NFT_PIPAPO_MAX_BYTES];
+ int i;
+
+ memcpy(tmp, base, len);
+
+ /* Network order, byte-addressed */
+ for (i = 0; i <= step; i++)
+#ifdef __BIG_ENDIAN__
+ tmp[i / BITS_PER_BYTE] |= BIT(i % BITS_PER_BYTE);
+#else
+ tmp[len - 1 - i / BITS_PER_BYTE] |= BIT(i % BITS_PER_BYTE);
+#endif
+
+ return memcmp(tmp, end, len) > 0;
+}
+
+/**
+ * pipapo_base_sum() - Sum step bit to given len-sized netmask base with carry
+ * @base: Netmask base
+ * @step: Step bit to sum
+ * @len: Netmask length, bytes
+ */
+static void pipapo_base_sum(u8 *base, int step, int len)
+{
+ bool carry = false;
+ int i;
+
+ /* Network order, byte-addressed */
+#ifdef __BIG_ENDIAN__
+ for (i = step / BITS_PER_BYTE; i < len; i++) {
+#else
+ for (i = len - 1 - step / BITS_PER_BYTE; i >= 0; i--) {
+#endif
+ if (carry)
+ base[i]++;
+ else
+ base[i] += 1 << (step % BITS_PER_BYTE);
+
+ if (base[i])
+ break;
+
+ carry = true;
+ }
+}
+
+/**
+ * pipapo_expand() - Expand to composing netmasks, insert into lookup table
+ * @f: Field containing lookup table
+ * @start: Start of range
+ * @end: End of range
+ * @len: Length of value in bits
+ *
+ * Expand range to composing netmasks and insert corresponding rule references
+ * in lookup buckets.
+ *
+ * Return: number of inserted rules on success, negative error code on failure.
+ */
+static int pipapo_expand(struct nft_pipapo_field *f,
+ const u8 *start, const u8 *end, int len)
+{
+ int step, masks = 0, bytes = DIV_ROUND_UP(len, BITS_PER_BYTE);
+ u8 base[NFT_PIPAPO_MAX_BYTES];
+
+ memcpy(base, start, bytes);
+ while (memcmp(base, end, bytes) <= 0) {
+ int err;
+
+ step = 0;
+ while (pipapo_step_diff(base, step, bytes)) {
+ if (pipapo_step_after_end(base, end, step, bytes))
+ break;
+
+ step++;
+ if (step >= len) {
+ if (!masks) {
+ pipapo_insert(f, base, 0);
+ masks = 1;
+ }
+ goto out;
+ }
+ }
+
+ err = pipapo_insert(f, base, len - step);
+
+ if (err < 0)
+ return err;
+
+ masks++;
+ pipapo_base_sum(base, step, bytes);
+ }
+out:
+ return masks;
+}
+
+/**
+ * pipapo_map() - Insert rules in mapping tables, mapping them between fields
+ * @m: Matching data, including mapping table
+ * @map: Table of rule maps: array of first rule and amount of rules
+ * in next field a given rule maps to, for each field
+ * @ext: For last field, nft_set_ext pointer matching rules map to
+ */
+static void pipapo_map(struct nft_pipapo_match *m,
+ union nft_pipapo_map_bucket map[NFT_PIPAPO_MAX_FIELDS],
+ struct nft_pipapo_elem *e)
+{
+ struct nft_pipapo_field *f;
+ int i, j;
+
+ for (i = 0, f = m->f; i < m->field_count - 1; i++, f++) {
+ for (j = 0; j < map[i].n; j++) {
+ f->mt[map[i].to + j].to = map[i + 1].to;
+ f->mt[map[i].to + j].n = map[i + 1].n;
+ }
+ }
+
+ /* Last field: map to ext instead of mapping to next field */
+ for (j = 0; j < map[i].n; j++)
+ f->mt[map[i].to + j].e = e;
+}
+
+/**
+ * pipapo_realloc_scratch() - Reallocate scratch maps for partial match results
+ * @clone: Copy of matching data with pending insertions and deletions
+ * @bsize_max Maximum bucket size, scratch maps cover two buckets
+ *
+ * Return: 0 on success, -ENOMEM on failure.
+ */
+static int pipapo_realloc_scratch(struct nft_pipapo_match *clone,
+ unsigned long bsize_max)
+{
+ int i;
+
+ for_each_possible_cpu(i) {
+ unsigned long *scratch;
+
+ scratch = kzalloc_node(bsize_max * sizeof(*scratch) * 2,
+ GFP_KERNEL, cpu_to_node(i));
+ if (!scratch) {
+ /* On failure, there's no need to undo previous
+ * allocations: this means that some scratch maps have
+ * a bigger allocated size now (this is only called on
+ * insertion), but the extra space won't be used by any
+ * CPU as new elements are not inserted and m->bsize_max
+ * is not updated.
+ */
+ return -ENOMEM;
+ }
+
+ kfree(*per_cpu_ptr(clone->scratch, i));
+
+ *per_cpu_ptr(clone->scratch, i) = scratch;
+ }
+
+ return 0;
+}
+
+/**
+ * nft_pipapo_insert() - Validate and insert ranged elements
+ * @net: Network namespace
+ * @set: nftables API set representation
+ * @elem: nftables API element representation containing key data
+ * @ext2: Filled with pointer to &struct nft_set_ext in inserted element
+ *
+ * Return: 0 on success, error pointer on failure.
+ */
+static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,
+ const struct nft_set_elem *elem,
+ struct nft_set_ext **ext2)
+{
+ const struct nft_set_ext *ext = nft_set_elem_ext(set, elem->priv);
+ union nft_pipapo_map_bucket rulemap[NFT_PIPAPO_MAX_FIELDS];
+ const u8 *start = (const u8 *)elem->key.val.data, *end;
+ struct nft_pipapo_elem *e = elem->priv, *dup;
+ struct nft_pipapo *priv = nft_set_priv(set);
+ struct nft_pipapo_match *m = priv->clone;
+ u8 genmask = nft_genmask_next(net);
+ struct nft_pipapo_field *f;
+ int i, bsize_max, err = 0;
+
+ dup = pipapo_get(net, set, start, genmask);
+ if (PTR_ERR(dup) == -ENOENT) {
+ if (nft_set_ext_exists(ext, NFT_SET_EXT_KEY_END)) {
+ end = (const u8 *)nft_set_ext_key_end(ext)->data;
+ dup = pipapo_get(net, set, end, nft_genmask_next(net));
+ } else {
+ end = start;
+ }
+ }
+
+ if (PTR_ERR(dup) != -ENOENT) {
+ if (IS_ERR(dup))
+ return PTR_ERR(dup);
+ *ext2 = &dup->ext;
+ return -EEXIST;
+ }
+
+ /* Validate */
+ nft_pipapo_for_each_field(f, i, m) {
+ const u8 *start_p = start, *end_p = end;
+
+ if (f->rules >= (unsigned long)NFT_PIPAPO_RULE0_MAX)
+ return -ENOSPC;
+
+ if (memcmp(start_p, end_p,
+ f->groups / NFT_PIPAPO_GROUPS_PER_BYTE) > 0)
+ return -EINVAL;
+
+ start_p += NFT_PIPAPO_GROUPS_PADDED_SIZE(f->groups);
+ end_p += NFT_PIPAPO_GROUPS_PADDED_SIZE(f->groups);
+ }
+
+ /* Insert */
+ priv->dirty = true;
+
+ bsize_max = m->bsize_max;
+
+ nft_pipapo_for_each_field(f, i, m) {
+ int ret;
+
+ rulemap[i].to = f->rules;
+
+ ret = memcmp(start, end,
+ f->groups / NFT_PIPAPO_GROUPS_PER_BYTE);
+ if (!ret) {
+ ret = pipapo_insert(f, start,
+ f->groups * NFT_PIPAPO_GROUP_BITS);
+ } else {
+ ret = pipapo_expand(f, start, end,
+ f->groups * NFT_PIPAPO_GROUP_BITS);
+ }
+
+ if (f->bsize > bsize_max)
+ bsize_max = f->bsize;
+
+ rulemap[i].n = ret;
+
+ start += NFT_PIPAPO_GROUPS_PADDED_SIZE(f->groups);
+ end += NFT_PIPAPO_GROUPS_PADDED_SIZE(f->groups);
+ }
+
+ if (!*this_cpu_ptr(m->scratch) || bsize_max > m->bsize_max) {
+ err = pipapo_realloc_scratch(m, bsize_max);
+ if (err)
+ return err;
+
+ this_cpu_write(nft_pipapo_scratch_index, false);
+
+ m->bsize_max = bsize_max;
+ }
+
+ *ext2 = &e->ext;
+
+ pipapo_map(m, rulemap, e);
+
+ return 0;
+}
+
+/**
+ * pipapo_clone() - Clone matching data to create new working copy
+ * @old: Existing matching data
+ *
+ * Return: copy of matching data passed as 'old', error pointer on failure
+ */
+static struct nft_pipapo_match *pipapo_clone(struct nft_pipapo_match *old)
+{
+ struct nft_pipapo_field *dst, *src;
+ struct nft_pipapo_match *new;
+ int i;
+
+ new = kmalloc(sizeof(*new) + sizeof(*dst) * old->field_count,
+ GFP_KERNEL);
+ if (!new)
+ return ERR_PTR(-ENOMEM);
+
+ new->field_count = old->field_count;
+ new->bsize_max = old->bsize_max;
+
+ new->scratch = alloc_percpu(*new->scratch);
+ if (!new->scratch)
+ goto out_scratch;
+
+ rcu_head_init(&new->rcu);
+
+ src = old->f;
+ dst = new->f;
+
+ for (i = 0; i < old->field_count; i++) {
+ memcpy(dst, src, offsetof(struct nft_pipapo_field, lt));
+
+ dst->lt = kvzalloc(src->groups * NFT_PIPAPO_BUCKETS *
+ src->bsize * sizeof(*dst->lt),
+ GFP_KERNEL);
+ if (!dst->lt)
+ goto out_lt;
+
+ memcpy(dst->lt, src->lt,
+ src->bsize * sizeof(*dst->lt) *
+ src->groups * NFT_PIPAPO_BUCKETS);
+
+ dst->mt = kvmalloc(src->rules * sizeof(*src->mt), GFP_KERNEL);
+ if (!dst->mt)
+ goto out_mt;
+
+ memcpy(dst->mt, src->mt, src->rules * sizeof(*src->mt));
+ src++;
+ dst++;
+ }
+
+ return new;
+
+out_mt:
+ kvfree(dst->lt);
+out_lt:
+ for (dst--; i > 0; i--) {
+ kvfree(dst->mt);
+ kvfree(dst->lt);
+ dst--;
+ }
+ free_percpu(new->scratch);
+out_scratch:
+ kfree(new);
+
+ return ERR_PTR(-ENOMEM);
+}
+
+/**
+ * pipapo_rules_same_key() - Get number of rules originated from the same entry
+ * @f: Field containing mapping table
+ * @first: Index of first rule in set of rules mapping to same entry
+ *
+ * Using the fact that all rules in a field that originated from the same entry
+ * will map to the same set of rules in the next field, or to the same element
+ * reference, return the cardinality of the set of rules that originated from
+ * the same entry as the rule with index @first, @first rule included.
+ *
+ * In pictures:
+ * rules
+ * field #0 0 1 2 3 4
+ * map to: 0 1 2-4 2-4 5-9
+ * . . ....... . ...
+ * | | | | \ \
+ * | | | | \ \
+ * | | | | \ \
+ * ' ' ' ' ' \
+ * in field #1 0 1 2 3 4 5 ...
+ *
+ * if this is called for rule 2 on field #0, it will return 3, as also rules 2
+ * and 3 in field 0 map to the same set of rules (2, 3, 4) in the next field.
+ *
+ * For the last field in a set, we can rely on associated entries to map to the
+ * same element references.
+ *
+ * Return: Number of rules that originated from the same entry as @first.
+ */
+static int pipapo_rules_same_key(struct nft_pipapo_field *f, int first)
+{
+ struct nft_pipapo_elem *e = NULL; /* Keep gcc happy */
+ int r;
+
+ for (r = first; r < f->rules; r++) {
+ if (r != first && e != f->mt[r].e)
+ return r - first;
+
+ e = f->mt[r].e;
+ }
+
+ if (r != first)
+ return r - first;
+
+ return 0;
+}
+
+/**
+ * pipapo_unmap() - Remove rules from mapping tables, renumber remaining ones
+ * @mt: Mapping array
+ * @rules: Original amount of rules in mapping table
+ * @start: First rule index to be removed
+ * @n: Amount of rules to be removed
+ * @to_offset: First rule index, in next field, this group of rules maps to
+ * @is_last: If this is the last field, delete reference from mapping array
+ *
+ * This is used to unmap rules from the mapping table for a single field,
+ * maintaining consistency and compactness for the existing ones.
+ *
+ * In pictures: let's assume that we want to delete rules 2 and 3 from the
+ * following mapping array:
+ *
+ * rules
+ * 0 1 2 3 4
+ * map to: 4-10 4-10 11-15 11-15 16-18
+ *
+ * the result will be:
+ *
+ * rules
+ * 0 1 2
+ * map to: 4-10 4-10 11-13
+ *
+ * for fields before the last one. In case this is the mapping table for the
+ * last field in a set, and rules map to pointers to &struct nft_pipapo_elem:
+ *
+ * rules
+ * 0 1 2 3 4
+ * element pointers: 0x42 0x42 0x33 0x33 0x44
+ *
+ * the result will be:
+ *
+ * rules
+ * 0 1 2
+ * element pointers: 0x42 0x42 0x44
+ */
+static void pipapo_unmap(union nft_pipapo_map_bucket *mt, int rules,
+ int start, int n, int to_offset, bool is_last)
+{
+ int i;
+
+ memmove(mt + start, mt + start + n, (rules - start - n) * sizeof(*mt));
+ memset(mt + rules - n, 0, n * sizeof(*mt));
+
+ if (is_last)
+ return;
+
+ for (i = start; i < rules - n; i++)
+ mt[i].to -= to_offset;
+}
+
+/**
+ * pipapo_drop() - Delete entry from lookup and mapping tables, given rule map
+ * @m: Matching data
+ * @rulemap Table of rule maps, arrays of first rule and amount of rules
+ * in next field a given entry maps to, for each field
+ *
+ * For each rule in lookup table buckets mapping to this set of rules, drop
+ * all bits set in lookup table mapping. In pictures, assuming we want to drop
+ * rules 0 and 1 from this lookup table:
+ *
+ * bucket
+ * group 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
+ * 0 0 1,2
+ * 1 1,2 0
+ * 2 0 1,2
+ * 3 0 1,2
+ * 4 0,1,2
+ * 5 0 1 2
+ * 6 0,1,2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
+ * 7 1,2 1,2 1 1 1 0,1 1 1 1 1 1 1 1 1 1 1
+ *
+ * rule 2 becomes rule 0, and the result will be:
+ *
+ * bucket
+ * group 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
+ * 0 0
+ * 1 0
+ * 2 0
+ * 3 0
+ * 4 0
+ * 5 0
+ * 6 0
+ * 7 0 0
+ *
+ * once this is done, call unmap() to drop all the corresponding rule references
+ * from mapping tables.
+ */
+static void pipapo_drop(struct nft_pipapo_match *m,
+ union nft_pipapo_map_bucket rulemap[])
+{
+ struct nft_pipapo_field *f;
+ int i;
+
+ nft_pipapo_for_each_field(f, i, m) {
+ int g;
+
+ for (g = 0; g < f->groups; g++) {
+ unsigned long *pos;
+ int b;
+
+ pos = f->lt + g * NFT_PIPAPO_BUCKETS * f->bsize;
+
+ for (b = 0; b < NFT_PIPAPO_BUCKETS; b++) {
+ bitmap_cut(pos, pos, rulemap[i].to,
+ rulemap[i].n,
+ f->bsize * BITS_PER_LONG);
+
+ pos += f->bsize;
+ }
+ }
+
+ pipapo_unmap(f->mt, f->rules, rulemap[i].to, rulemap[i].n,
+ rulemap[i + 1].n, i == m->field_count - 1);
+ if (pipapo_resize(f, f->rules, f->rules - rulemap[i].n)) {
+ /* We can ignore this, a failure to shrink tables down
+ * doesn't make tables invalid.
+ */
+ ;
+ }
+ f->rules -= rulemap[i].n;
+ }
+}
+
+/**
+ * pipapo_gc() - Drop expired entries from set, destroy start and end elements
+ * @set: nftables API set representation
+ * @m: Matching data
+ */
+static void pipapo_gc(const struct nft_set *set, struct nft_pipapo_match *m)
+{
+ struct nft_pipapo *priv = nft_set_priv(set);
+ int rules_f0, first_rule = 0;
+
+ while ((rules_f0 = pipapo_rules_same_key(m->f, first_rule))) {
+ union nft_pipapo_map_bucket rulemap[NFT_PIPAPO_MAX_FIELDS];
+ struct nft_pipapo_field *f;
+ struct nft_pipapo_elem *e;
+ int i, start, rules_fx;
+
+ start = first_rule;
+ rules_fx = rules_f0;
+
+ nft_pipapo_for_each_field(f, i, m) {
+ rulemap[i].to = start;
+ rulemap[i].n = rules_fx;
+
+ if (i < m->field_count - 1) {
+ rules_fx = f->mt[start].n;
+ start = f->mt[start].to;
+ }
+ }
+
+ /* Pick the last field, and its last index */
+ f--;
+ i--;
+ e = f->mt[rulemap[i].to].e;
+ if (nft_set_elem_expired(&e->ext) &&
+ !nft_set_elem_mark_busy(&e->ext)) {
+ priv->dirty = true;
+ pipapo_drop(m, rulemap);
+
+ rcu_barrier();
+ nft_set_elem_destroy(set, e, true);
+
+ /* And check again current first rule, which is now the
+ * first we haven't checked.
+ */
+ } else {
+ first_rule += rules_f0;
+ }
+ }
+
+ priv->last_gc = jiffies;
+}
+
+/**
+ * pipapo_free_fields() - Free per-field tables contained in matching data
+ * @m: Matching data
+ */
+static void pipapo_free_fields(struct nft_pipapo_match *m)
+{
+ struct nft_pipapo_field *f;
+ int i;
+
+ nft_pipapo_for_each_field(f, i, m) {
+ kvfree(f->lt);
+ kvfree(f->mt);
+ }
+}
+
+/**
+ * pipapo_reclaim_match - RCU callback to free fields from old matching data
+ * @rcu: RCU head
+ */
+static void pipapo_reclaim_match(struct rcu_head *rcu)
+{
+ struct nft_pipapo_match *m;
+ int i;
+
+ m = container_of(rcu, struct nft_pipapo_match, rcu);
+
+ for_each_possible_cpu(i)
+ kfree(*per_cpu_ptr(m->scratch, i));
+
+ free_percpu(m->scratch);
+
+ pipapo_free_fields(m);
+
+ kfree(m);
+}
+
+/**
+ * pipapo_commit() - Replace lookup data with current working copy
+ * @set: nftables API set representation
+ *
+ * While at it, check if we should perform garbage collection on the working
+ * copy before committing it for lookup, and don't replace the table if the
+ * working copy doesn't have pending changes.
+ *
+ * We also need to create a new working copy for subsequent insertions and
+ * deletions.
+ */
+static void pipapo_commit(const struct nft_set *set)
+{
+ struct nft_pipapo *priv = nft_set_priv(set);
+ struct nft_pipapo_match *new_clone, *old;
+
+ if (time_after_eq(jiffies, priv->last_gc + nft_set_gc_interval(set)))
+ pipapo_gc(set, priv->clone);
+
+ if (!priv->dirty)
+ return;
+
+ new_clone = pipapo_clone(priv->clone);
+ if (IS_ERR(new_clone))
+ return;
+
+ priv->dirty = false;
+
+ old = rcu_access_pointer(priv->match);
+ rcu_assign_pointer(priv->match, priv->clone);
+ if (old)
+ call_rcu(&old->rcu, pipapo_reclaim_match);
+
+ priv->clone = new_clone;
+}
+
+/**
+ * nft_pipapo_activate() - Mark element reference as active given key, commit
+ * @net: Network namespace
+ * @set: nftables API set representation
+ * @elem: nftables API element representation containing key data
+ *
+ * On insertion, elements are added to a copy of the matching data currently
+ * in use for lookups, and not directly inserted into current lookup data, so
+ * we'll take care of that by calling pipapo_commit() here. Both
+ * nft_pipapo_insert() and nft_pipapo_activate() are called once for each
+ * element, hence we can't purpose either one as a real commit operation.
+ */
+static void nft_pipapo_activate(const struct net *net,
+ const struct nft_set *set,
+ const struct nft_set_elem *elem)
+{
+ struct nft_pipapo_elem *e;
+
+ e = pipapo_get(net, set, (const u8 *)elem->key.val.data, 0);
+ if (IS_ERR(e))
+ return;
+
+ nft_set_elem_change_active(net, set, &e->ext);
+ nft_set_elem_clear_busy(&e->ext);
+
+ pipapo_commit(set);
+}
+
+/**
+ * pipapo_deactivate() - Check that element is in set, mark as inactive
+ * @net: Network namespace
+ * @set: nftables API set representation
+ * @data: Input key data
+ * @ext: nftables API extension pointer, used to check for end element
+ *
+ * This is a convenience function that can be called from both
+ * nft_pipapo_deactivate() and nft_pipapo_flush(), as they are in fact the same
+ * operation.
+ *
+ * Return: deactivated element if found, NULL otherwise.
+ */
+static void *pipapo_deactivate(const struct net *net, const struct nft_set *set,
+ const u8 *data, const struct nft_set_ext *ext)
+{
+ struct nft_pipapo_elem *e;
+
+ e = pipapo_get(net, set, data, nft_genmask_next(net));
+ if (IS_ERR(e))
+ return NULL;
+
+ nft_set_elem_change_active(net, set, &e->ext);
+
+ return e;
+}
+
+/**
+ * nft_pipapo_deactivate() - Call pipapo_deactivate() to make element inactive
+ * @net: Network namespace
+ * @set: nftables API set representation
+ * @elem: nftables API element representation containing key data
+ *
+ * Return: deactivated element if found, NULL otherwise.
+ */
+static void *nft_pipapo_deactivate(const struct net *net,
+ const struct nft_set *set,
+ const struct nft_set_elem *elem)
+{
+ const struct nft_set_ext *ext = nft_set_elem_ext(set, elem->priv);
+
+ return pipapo_deactivate(net, set, (const u8 *)elem->key.val.data, ext);
+}
+
+/**
+ * nft_pipapo_flush() - Call pipapo_deactivate() to make element inactive
+ * @net: Network namespace
+ * @set: nftables API set representation
+ * @elem: nftables API element representation containing key data
+ *
+ * This is functionally the same as nft_pipapo_deactivate(), with a slightly
+ * different interface, and it's also called once for each element in a set
+ * being flushed, so we can't implement, strictly speaking, a flush operation,
+ * which would otherwise be as simple as allocating an empty copy of the
+ * matching data.
+ *
+ * Note that we could in theory do that, mark the set as flushed, and ignore
+ * subsequent calls, but we would leak all the elements after the first one,
+ * because they wouldn't then be freed as result of API calls.
+ *
+ * Return: true if element was found and deactivated.
+ */
+static bool nft_pipapo_flush(const struct net *net, const struct nft_set *set,
+ void *elem)
+{
+ struct nft_pipapo_elem *e = elem;
+
+ return pipapo_deactivate(net, set, (const u8 *)nft_set_ext_key(&e->ext),
+ &e->ext);
+}
+
+/**
+ * pipapo_get_boundaries() - Get byte interval for associated rules
+ * @f: Field including lookup table
+ * @first_rule: First rule (lowest index)
+ * @rule_count: Number of associated rules
+ * @left: Byte expression for left boundary (start of range)
+ * @right: Byte expression for right boundary (end of range)
+ *
+ * Given the first rule and amount of rules that originated from the same entry,
+ * build the original range associated with the entry, and calculate the length
+ * of the originating netmask.
+ *
+ * In pictures:
+ *
+ * bucket
+ * group 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
+ * 0 1,2
+ * 1 1,2
+ * 2 1,2
+ * 3 1,2
+ * 4 1,2
+ * 5 1 2
+ * 6 1,2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
+ * 7 1,2 1,2 1 1 1 1 1 1 1 1 1 1 1 1 1 1
+ *
+ * this is the lookup table corresponding to the IPv4 range
+ * 192.168.1.0-192.168.2.1, which was expanded to the two composing netmasks,
+ * rule #1: 192.168.1.0/24, and rule #2: 192.168.2.0/31.
+ *
+ * This function fills @left and @right with the byte values of the leftmost
+ * and rightmost bucket indices for the lowest and highest rule indices,
+ * respectively. If @first_rule is 1 and @rule_count is 2, we obtain, in
+ * nibbles:
+ * left: < 12, 0, 10, 8, 0, 1, 0, 0 >
+ * right: < 12, 0, 10, 8, 0, 2, 2, 1 >
+ * corresponding to bytes:
+ * left: < 192, 168, 1, 0 >
+ * right: < 192, 168, 2, 1 >
+ * with mask length irrelevant here, unused on return, as the range is already
+ * defined by its start and end points. The mask length is relevant for a single
+ * ranged entry instead: if @first_rule is 1 and @rule_count is 1, we ignore
+ * rule 2 above: @left becomes < 192, 168, 1, 0 >, @right becomes
+ * < 192, 168, 1, 255 >, and the mask length, calculated from the distances
+ * between leftmost and rightmost bucket indices for each group, would be 24.
+ *
+ * Return: mask length, in bits.
+ */
+static int pipapo_get_boundaries(struct nft_pipapo_field *f, int first_rule,
+ int rule_count, u8 *left, u8 *right)
+{
+ u8 *l = left, *r = right;
+ int g, mask_len = 0;
+
+ for (g = 0; g < f->groups; g++) {
+ int b, x0, x1;
+
+ x0 = -1;
+ x1 = -1;
+ for (b = 0; b < NFT_PIPAPO_BUCKETS; b++) {
+ unsigned long *pos;
+
+ pos = f->lt + (g * NFT_PIPAPO_BUCKETS + b) * f->bsize;
+ if (test_bit(first_rule, pos) && x0 == -1)
+ x0 = b;
+ if (test_bit(first_rule + rule_count - 1, pos))
+ x1 = b;
+ }
+
+ if (g % 2) {
+ *(l++) |= x0 & 0x0f;
+ *(r++) |= x1 & 0x0f;
+ } else {
+ *l |= x0 << 4;
+ *r |= x1 << 4;
+ }
+
+ if (x1 - x0 == 0)
+ mask_len += 4;
+ else if (x1 - x0 == 1)
+ mask_len += 3;
+ else if (x1 - x0 == 3)
+ mask_len += 2;
+ else if (x1 - x0 == 7)
+ mask_len += 1;
+ }
+
+ return mask_len;
+}
+
+/**
+ * pipapo_match_field() - Match rules against byte ranges
+ * @f: Field including the lookup table
+ * @first_rule: First of associated rules originating from same entry
+ * @rule_count: Amount of associated rules
+ * @start: Start of range to be matched
+ * @end: End of range to be matched
+ *
+ * Return: true on match, false otherwise.
+ */
+static bool pipapo_match_field(struct nft_pipapo_field *f,
+ int first_rule, int rule_count,
+ const u8 *start, const u8 *end)
+{
+ u8 right[NFT_PIPAPO_MAX_BYTES] = { 0 };
+ u8 left[NFT_PIPAPO_MAX_BYTES] = { 0 };
+
+ pipapo_get_boundaries(f, first_rule, rule_count, left, right);
+
+ return !memcmp(start, left, f->groups / NFT_PIPAPO_GROUPS_PER_BYTE) &&
+ !memcmp(end, right, f->groups / NFT_PIPAPO_GROUPS_PER_BYTE);
+}
+
+/**
+ * nft_pipapo_remove() - Remove element given key, commit
+ * @net: Network namespace
+ * @set: nftables API set representation
+ * @elem: nftables API element representation containing key data
+ *
+ * Similarly to nft_pipapo_activate(), this is used as commit operation by the
+ * API, but it's called once per element in the pending transaction, so we can't
+ * implement this as a single commit operation. Closest we can get is to remove
+ * the matched element here, if any, and commit the updated matching data.
+ */
+static void nft_pipapo_remove(const struct net *net, const struct nft_set *set,
+ const struct nft_set_elem *elem)
+{
+ const u8 *data = (const u8 *)elem->key.val.data;
+ struct nft_pipapo *priv = nft_set_priv(set);
+ struct nft_pipapo_match *m = priv->clone;
+ int rules_f0, first_rule = 0;
+ struct nft_pipapo_elem *e;
+
+ e = pipapo_get(net, set, data, 0);
+ if (IS_ERR(e))
+ return;
+
+ while ((rules_f0 = pipapo_rules_same_key(m->f, first_rule))) {
+ union nft_pipapo_map_bucket rulemap[NFT_PIPAPO_MAX_FIELDS];
+ const u8 *match_start, *match_end;
+ struct nft_pipapo_field *f;
+ int i, start, rules_fx;
+
+ match_start = data;
+ match_end = (const u8 *)nft_set_ext_key_end(&e->ext)->data;
+
+ start = first_rule;
+ rules_fx = rules_f0;
+
+ nft_pipapo_for_each_field(f, i, m) {
+ if (!pipapo_match_field(f, start, rules_fx,
+ match_start, match_end))
+ break;
+
+ rulemap[i].to = start;
+ rulemap[i].n = rules_fx;
+
+ rules_fx = f->mt[start].n;
+ start = f->mt[start].to;
+
+ match_start += NFT_PIPAPO_GROUPS_PADDED_SIZE(f->groups);
+ match_end += NFT_PIPAPO_GROUPS_PADDED_SIZE(f->groups);
+ }
+
+ if (i == m->field_count) {
+ priv->dirty = true;
+ pipapo_drop(m, rulemap);
+ pipapo_commit(set);
+ return;
+ }
+
+ first_rule += rules_f0;
+ }
+}
+
+/**
+ * nft_pipapo_walk() - Walk over elements
+ * @ctx: nftables API context
+ * @set: nftables API set representation
+ * @iter: Iterator
+ *
+ * As elements are referenced in the mapping array for the last field, directly
+ * scan that array: there's no need to follow rule mappings from the first
+ * field.
+ */
+static void nft_pipapo_walk(const struct nft_ctx *ctx, struct nft_set *set,
+ struct nft_set_iter *iter)
+{
+ struct nft_pipapo *priv = nft_set_priv(set);
+ struct nft_pipapo_match *m;
+ struct nft_pipapo_field *f;
+ int i, r;
+
+ rcu_read_lock();
+ m = rcu_dereference(priv->match);
+
+ if (unlikely(!m))
+ goto out;
+
+ for (i = 0, f = m->f; i < m->field_count - 1; i++, f++)
+ ;
+
+ for (r = 0; r < f->rules; r++) {
+ struct nft_pipapo_elem *e;
+ struct nft_set_elem elem;
+
+ if (r < f->rules - 1 && f->mt[r + 1].e == f->mt[r].e)
+ continue;
+
+ if (iter->count < iter->skip)
+ goto cont;
+
+ e = f->mt[r].e;
+ if (nft_set_elem_expired(&e->ext))
+ goto cont;
+
+ elem.priv = e;
+
+ iter->err = iter->fn(ctx, set, iter, &elem);
+ if (iter->err < 0)
+ goto out;
+
+cont:
+ iter->count++;
+ }
+
+out:
+ rcu_read_unlock();
+}
+
+/**
+ * nft_pipapo_privsize() - Return the size of private data for the set
+ * @nla: netlink attributes, ignored as size doesn't depend on them
+ * @desc: Set description, ignored as size doesn't depend on it
+ *
+ * Return: size of private data for this set implementation, in bytes
+ */
+static u64 nft_pipapo_privsize(const struct nlattr * const nla[],
+ const struct nft_set_desc *desc)
+{
+ return sizeof(struct nft_pipapo);
+}
+
+/**
+ * nft_pipapo_estimate() - Estimate set size, space and lookup complexity
+ * @desc: Set description, element count and field description used here
+ * @features: Flags: NFT_SET_INTERVAL needs to be there
+ * @est: Storage for estimation data
+ *
+ * The size for this set type can vary dramatically, as it depends on the number
+ * of rules (composing netmasks) the entries expand to. We compute the worst
+ * case here.
+ *
+ * In general, for a non-ranged entry or a single composing netmask, we need
+ * one bit in each of the sixteen NFT_PIPAPO_BUCKETS, for each 4-bit group (that
+ * is, each input bit needs four bits of matching data), plus a bucket in the
+ * mapping table for each field.
+ *
+ * Return: true only for compatible range concatenations
+ */
+static bool nft_pipapo_estimate(const struct nft_set_desc *desc, u32 features,
+ struct nft_set_estimate *est)
+{
+ unsigned long entry_size;
+ int i;
+
+ if (!(features & NFT_SET_INTERVAL) || desc->field_count <= 1)
+ return false;
+
+ for (i = 0, entry_size = 0; i < desc->field_count; i++) {
+ unsigned long rules;
+
+ if (desc->field_len[i] > NFT_PIPAPO_MAX_BYTES)
+ return false;
+
+ /* Worst-case ranges for each concatenated field: each n-bit
+ * field can expand to up to n * 2 rules in each bucket, and
+ * each rule also needs a mapping bucket.
+ */
+ rules = ilog2(desc->field_len[i] * BITS_PER_BYTE) * 2;
+ entry_size += rules * NFT_PIPAPO_BUCKETS / BITS_PER_BYTE;
+ entry_size += rules * sizeof(union nft_pipapo_map_bucket);
+ }
+
+ /* Rules in lookup and mapping tables are needed for each entry */
+ est->size = desc->size * entry_size;
+ if (est->size && div_u64(est->size, desc->size) != entry_size)
+ return false;
+
+ est->size += sizeof(struct nft_pipapo) +
+ sizeof(struct nft_pipapo_match) * 2;
+
+ est->size += sizeof(struct nft_pipapo_field) * desc->field_count;
+
+ est->lookup = NFT_SET_CLASS_O_LOG_N;
+
+ est->space = NFT_SET_CLASS_O_N;
+
+ return true;
+}
+
+/**
+ * nft_pipapo_init() - Initialise data for a set instance
+ * @set: nftables API set representation
+ * @desc: Set description
+ * @nla: netlink attributes
+ *
+ * Validate number and size of fields passed as NFTA_SET_DESC_CONCAT netlink
+ * attributes, initialise internal set parameters, current instance of matching
+ * data and a copy for subsequent insertions.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+static int nft_pipapo_init(const struct nft_set *set,
+ const struct nft_set_desc *desc,
+ const struct nlattr * const nla[])
+{
+ struct nft_pipapo *priv = nft_set_priv(set);
+ struct nft_pipapo_match *m;
+ struct nft_pipapo_field *f;
+ int err, i;
+
+ if (desc->field_count > NFT_PIPAPO_MAX_FIELDS)
+ return -EINVAL;
+
+ m = kmalloc(sizeof(*priv->match) + sizeof(*f) * desc->field_count,
+ GFP_KERNEL);
+ if (!m)
+ return -ENOMEM;
+
+ m->field_count = desc->field_count;
+ m->bsize_max = 0;
+
+ m->scratch = alloc_percpu(unsigned long *);
+ if (!m->scratch) {
+ err = -ENOMEM;
+ goto out_free;
+ }
+ for_each_possible_cpu(i)
+ *per_cpu_ptr(m->scratch, i) = NULL;
+
+ rcu_head_init(&m->rcu);
+
+ nft_pipapo_for_each_field(f, i, m) {
+ f->groups = desc->field_len[i] * NFT_PIPAPO_GROUPS_PER_BYTE;
+ priv->groups += f->groups;
+
+ priv->width += round_up(desc->field_len[i], sizeof(u32));
+
+ f->bsize = 0;
+ f->rules = 0;
+ f->lt = NULL;
+ f->mt = NULL;
+ }
+
+ /* Create an initial clone of matching data for next insertion */
+ priv->clone = pipapo_clone(m);
+ if (IS_ERR(priv->clone)) {
+ err = PTR_ERR(priv->clone);
+ goto out_free;
+ }
+
+ priv->dirty = false;
+
+ rcu_assign_pointer(priv->match, m);
+
+ return 0;
+
+out_free:
+ free_percpu(m->scratch);
+ kfree(m);
+
+ return err;
+}
+
+/**
+ * nft_pipapo_destroy() - Free private data for set and all committed elements
+ * @set: nftables API set representation
+ */
+static void nft_pipapo_destroy(const struct nft_set *set)
+{
+ struct nft_pipapo *priv = nft_set_priv(set);
+ struct nft_pipapo_match *m;
+ struct nft_pipapo_field *f;
+ int i, r, cpu;
+
+ m = rcu_dereference_protected(priv->match, true);
+ if (m) {
+ rcu_barrier();
+
+ for (i = 0, f = m->f; i < m->field_count - 1; i++, f++)
+ ;
+
+ for (r = 0; r < f->rules; r++) {
+ struct nft_pipapo_elem *e;
+
+ if (r < f->rules - 1 && f->mt[r + 1].e == f->mt[r].e)
+ continue;
+
+ e = f->mt[r].e;
+
+ nft_set_elem_destroy(set, e, true);
+ }
+
+ for_each_possible_cpu(cpu)
+ kfree(*per_cpu_ptr(m->scratch, cpu));
+ free_percpu(m->scratch);
+
+ pipapo_free_fields(m);
+ kfree(m);
+ priv->match = NULL;
+ }
+
+ if (priv->clone) {
+ for_each_possible_cpu(cpu)
+ kfree(*per_cpu_ptr(priv->clone->scratch, cpu));
+ free_percpu(priv->clone->scratch);
+
+ pipapo_free_fields(priv->clone);
+ kfree(priv->clone);
+ priv->clone = NULL;
+ }
+}
+
+/**
+ * nft_pipapo_gc_init() - Initialise garbage collection
+ * @set: nftables API set representation
+ *
+ * Instead of actually setting up a periodic work for garbage collection, as
+ * this operation requires a swap of matching data with the working copy, we'll
+ * do that opportunistically with other commit operations if the interval is
+ * elapsed, so we just need to set the current jiffies timestamp here.
+ */
+static void nft_pipapo_gc_init(const struct nft_set *set)
+{
+ struct nft_pipapo *priv = nft_set_priv(set);
+
+ priv->last_gc = jiffies;
+}
+
+struct nft_set_type nft_set_pipapo_type __read_mostly = {
+ .owner = THIS_MODULE,
+ .features = NFT_SET_INTERVAL | NFT_SET_MAP | NFT_SET_OBJECT |
+ NFT_SET_TIMEOUT,
+ .ops = {
+ .lookup = nft_pipapo_lookup,
+ .insert = nft_pipapo_insert,
+ .activate = nft_pipapo_activate,
+ .deactivate = nft_pipapo_deactivate,
+ .flush = nft_pipapo_flush,
+ .remove = nft_pipapo_remove,
+ .walk = nft_pipapo_walk,
+ .get = nft_pipapo_get,
+ .privsize = nft_pipapo_privsize,
+ .estimate = nft_pipapo_estimate,
+ .init = nft_pipapo_init,
+ .destroy = nft_pipapo_destroy,
+ .gc_init = nft_pipapo_gc_init,
+ .elemsize = offsetof(struct nft_pipapo_elem, ext),
+ },
+};