cbddcb574d
Do not use rlimit-based memory accounting for lpm_trie maps. It has been replaced with the memcg-based memory accounting. Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20201201215900.3569844-25-guro@fb.com
733 lines
21 KiB
C
733 lines
21 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Longest prefix match list implementation
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*
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* Copyright (c) 2016,2017 Daniel Mack
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* Copyright (c) 2016 David Herrmann
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*/
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#include <linux/bpf.h>
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#include <linux/btf.h>
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#include <linux/err.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <linux/vmalloc.h>
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#include <net/ipv6.h>
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#include <uapi/linux/btf.h>
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/* Intermediate node */
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#define LPM_TREE_NODE_FLAG_IM BIT(0)
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struct lpm_trie_node;
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struct lpm_trie_node {
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struct rcu_head rcu;
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struct lpm_trie_node __rcu *child[2];
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u32 prefixlen;
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u32 flags;
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u8 data[];
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};
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struct lpm_trie {
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struct bpf_map map;
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struct lpm_trie_node __rcu *root;
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size_t n_entries;
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size_t max_prefixlen;
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size_t data_size;
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spinlock_t lock;
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};
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/* This trie implements a longest prefix match algorithm that can be used to
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* match IP addresses to a stored set of ranges.
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*
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* Data stored in @data of struct bpf_lpm_key and struct lpm_trie_node is
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* interpreted as big endian, so data[0] stores the most significant byte.
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*
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* Match ranges are internally stored in instances of struct lpm_trie_node
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* which each contain their prefix length as well as two pointers that may
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* lead to more nodes containing more specific matches. Each node also stores
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* a value that is defined by and returned to userspace via the update_elem
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* and lookup functions.
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*
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* For instance, let's start with a trie that was created with a prefix length
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* of 32, so it can be used for IPv4 addresses, and one single element that
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* matches 192.168.0.0/16. The data array would hence contain
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* [0xc0, 0xa8, 0x00, 0x00] in big-endian notation. This documentation will
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* stick to IP-address notation for readability though.
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*
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* As the trie is empty initially, the new node (1) will be places as root
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* node, denoted as (R) in the example below. As there are no other node, both
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* child pointers are %NULL.
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*
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* +----------------+
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* | (1) (R) |
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* | 192.168.0.0/16 |
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* | value: 1 |
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* | [0] [1] |
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* +----------------+
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*
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* Next, let's add a new node (2) matching 192.168.0.0/24. As there is already
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* a node with the same data and a smaller prefix (ie, a less specific one),
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* node (2) will become a child of (1). In child index depends on the next bit
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* that is outside of what (1) matches, and that bit is 0, so (2) will be
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* child[0] of (1):
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*
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* +----------------+
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* | (1) (R) |
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* | 192.168.0.0/16 |
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* | value: 1 |
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* | [0] [1] |
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* +----------------+
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* |
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* +----------------+
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* | (2) |
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* | 192.168.0.0/24 |
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* | value: 2 |
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* | [0] [1] |
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* +----------------+
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*
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* The child[1] slot of (1) could be filled with another node which has bit #17
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* (the next bit after the ones that (1) matches on) set to 1. For instance,
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* 192.168.128.0/24:
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*
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* +----------------+
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* | (1) (R) |
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* | 192.168.0.0/16 |
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* | value: 1 |
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* | [0] [1] |
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* +----------------+
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* | |
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* +----------------+ +------------------+
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* | (2) | | (3) |
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* | 192.168.0.0/24 | | 192.168.128.0/24 |
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* | value: 2 | | value: 3 |
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* | [0] [1] | | [0] [1] |
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* +----------------+ +------------------+
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*
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* Let's add another node (4) to the game for 192.168.1.0/24. In order to place
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* it, node (1) is looked at first, and because (4) of the semantics laid out
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* above (bit #17 is 0), it would normally be attached to (1) as child[0].
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* However, that slot is already allocated, so a new node is needed in between.
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* That node does not have a value attached to it and it will never be
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* returned to users as result of a lookup. It is only there to differentiate
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* the traversal further. It will get a prefix as wide as necessary to
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* distinguish its two children:
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*
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* +----------------+
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* | (1) (R) |
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* | 192.168.0.0/16 |
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* | value: 1 |
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* | [0] [1] |
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* +----------------+
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* | |
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* +----------------+ +------------------+
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* | (4) (I) | | (3) |
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* | 192.168.0.0/23 | | 192.168.128.0/24 |
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* | value: --- | | value: 3 |
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* | [0] [1] | | [0] [1] |
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* +----------------+ +------------------+
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* | |
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* +----------------+ +----------------+
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* | (2) | | (5) |
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* | 192.168.0.0/24 | | 192.168.1.0/24 |
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* | value: 2 | | value: 5 |
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* | [0] [1] | | [0] [1] |
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* +----------------+ +----------------+
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*
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* 192.168.1.1/32 would be a child of (5) etc.
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*
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* An intermediate node will be turned into a 'real' node on demand. In the
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* example above, (4) would be re-used if 192.168.0.0/23 is added to the trie.
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*
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* A fully populated trie would have a height of 32 nodes, as the trie was
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* created with a prefix length of 32.
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*
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* The lookup starts at the root node. If the current node matches and if there
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* is a child that can be used to become more specific, the trie is traversed
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* downwards. The last node in the traversal that is a non-intermediate one is
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* returned.
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*/
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static inline int extract_bit(const u8 *data, size_t index)
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{
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return !!(data[index / 8] & (1 << (7 - (index % 8))));
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}
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/**
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* longest_prefix_match() - determine the longest prefix
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* @trie: The trie to get internal sizes from
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* @node: The node to operate on
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* @key: The key to compare to @node
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*
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* Determine the longest prefix of @node that matches the bits in @key.
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*/
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static size_t longest_prefix_match(const struct lpm_trie *trie,
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const struct lpm_trie_node *node,
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const struct bpf_lpm_trie_key *key)
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{
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u32 limit = min(node->prefixlen, key->prefixlen);
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u32 prefixlen = 0, i = 0;
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BUILD_BUG_ON(offsetof(struct lpm_trie_node, data) % sizeof(u32));
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BUILD_BUG_ON(offsetof(struct bpf_lpm_trie_key, data) % sizeof(u32));
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#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && defined(CONFIG_64BIT)
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/* data_size >= 16 has very small probability.
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* We do not use a loop for optimal code generation.
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*/
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if (trie->data_size >= 8) {
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u64 diff = be64_to_cpu(*(__be64 *)node->data ^
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*(__be64 *)key->data);
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prefixlen = 64 - fls64(diff);
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if (prefixlen >= limit)
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return limit;
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if (diff)
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return prefixlen;
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i = 8;
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}
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#endif
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while (trie->data_size >= i + 4) {
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u32 diff = be32_to_cpu(*(__be32 *)&node->data[i] ^
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*(__be32 *)&key->data[i]);
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prefixlen += 32 - fls(diff);
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if (prefixlen >= limit)
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return limit;
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if (diff)
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return prefixlen;
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i += 4;
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}
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if (trie->data_size >= i + 2) {
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u16 diff = be16_to_cpu(*(__be16 *)&node->data[i] ^
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*(__be16 *)&key->data[i]);
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prefixlen += 16 - fls(diff);
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if (prefixlen >= limit)
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return limit;
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if (diff)
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return prefixlen;
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i += 2;
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}
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if (trie->data_size >= i + 1) {
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prefixlen += 8 - fls(node->data[i] ^ key->data[i]);
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if (prefixlen >= limit)
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return limit;
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}
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return prefixlen;
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}
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/* Called from syscall or from eBPF program */
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static void *trie_lookup_elem(struct bpf_map *map, void *_key)
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{
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struct lpm_trie *trie = container_of(map, struct lpm_trie, map);
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struct lpm_trie_node *node, *found = NULL;
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struct bpf_lpm_trie_key *key = _key;
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/* Start walking the trie from the root node ... */
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for (node = rcu_dereference(trie->root); node;) {
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unsigned int next_bit;
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size_t matchlen;
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/* Determine the longest prefix of @node that matches @key.
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* If it's the maximum possible prefix for this trie, we have
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* an exact match and can return it directly.
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*/
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matchlen = longest_prefix_match(trie, node, key);
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if (matchlen == trie->max_prefixlen) {
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found = node;
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break;
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}
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/* If the number of bits that match is smaller than the prefix
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* length of @node, bail out and return the node we have seen
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* last in the traversal (ie, the parent).
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*/
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if (matchlen < node->prefixlen)
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break;
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/* Consider this node as return candidate unless it is an
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* artificially added intermediate one.
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*/
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if (!(node->flags & LPM_TREE_NODE_FLAG_IM))
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found = node;
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/* If the node match is fully satisfied, let's see if we can
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* become more specific. Determine the next bit in the key and
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* traverse down.
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*/
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next_bit = extract_bit(key->data, node->prefixlen);
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node = rcu_dereference(node->child[next_bit]);
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}
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if (!found)
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return NULL;
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return found->data + trie->data_size;
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}
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static struct lpm_trie_node *lpm_trie_node_alloc(const struct lpm_trie *trie,
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const void *value)
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{
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struct lpm_trie_node *node;
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size_t size = sizeof(struct lpm_trie_node) + trie->data_size;
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if (value)
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size += trie->map.value_size;
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node = bpf_map_kmalloc_node(&trie->map, size, GFP_ATOMIC | __GFP_NOWARN,
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trie->map.numa_node);
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if (!node)
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return NULL;
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node->flags = 0;
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if (value)
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memcpy(node->data + trie->data_size, value,
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trie->map.value_size);
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return node;
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}
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/* Called from syscall or from eBPF program */
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static int trie_update_elem(struct bpf_map *map,
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void *_key, void *value, u64 flags)
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{
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struct lpm_trie *trie = container_of(map, struct lpm_trie, map);
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struct lpm_trie_node *node, *im_node = NULL, *new_node = NULL;
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struct lpm_trie_node __rcu **slot;
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struct bpf_lpm_trie_key *key = _key;
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unsigned long irq_flags;
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unsigned int next_bit;
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size_t matchlen = 0;
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int ret = 0;
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if (unlikely(flags > BPF_EXIST))
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return -EINVAL;
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if (key->prefixlen > trie->max_prefixlen)
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return -EINVAL;
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spin_lock_irqsave(&trie->lock, irq_flags);
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/* Allocate and fill a new node */
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if (trie->n_entries == trie->map.max_entries) {
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ret = -ENOSPC;
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goto out;
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}
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new_node = lpm_trie_node_alloc(trie, value);
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if (!new_node) {
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ret = -ENOMEM;
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goto out;
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}
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trie->n_entries++;
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new_node->prefixlen = key->prefixlen;
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RCU_INIT_POINTER(new_node->child[0], NULL);
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RCU_INIT_POINTER(new_node->child[1], NULL);
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memcpy(new_node->data, key->data, trie->data_size);
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/* Now find a slot to attach the new node. To do that, walk the tree
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* from the root and match as many bits as possible for each node until
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* we either find an empty slot or a slot that needs to be replaced by
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* an intermediate node.
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*/
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slot = &trie->root;
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while ((node = rcu_dereference_protected(*slot,
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lockdep_is_held(&trie->lock)))) {
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matchlen = longest_prefix_match(trie, node, key);
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if (node->prefixlen != matchlen ||
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node->prefixlen == key->prefixlen ||
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node->prefixlen == trie->max_prefixlen)
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break;
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next_bit = extract_bit(key->data, node->prefixlen);
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slot = &node->child[next_bit];
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}
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/* If the slot is empty (a free child pointer or an empty root),
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* simply assign the @new_node to that slot and be done.
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*/
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if (!node) {
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rcu_assign_pointer(*slot, new_node);
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goto out;
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}
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/* If the slot we picked already exists, replace it with @new_node
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* which already has the correct data array set.
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*/
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if (node->prefixlen == matchlen) {
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new_node->child[0] = node->child[0];
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new_node->child[1] = node->child[1];
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if (!(node->flags & LPM_TREE_NODE_FLAG_IM))
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trie->n_entries--;
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rcu_assign_pointer(*slot, new_node);
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kfree_rcu(node, rcu);
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goto out;
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}
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/* If the new node matches the prefix completely, it must be inserted
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* as an ancestor. Simply insert it between @node and *@slot.
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*/
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if (matchlen == key->prefixlen) {
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next_bit = extract_bit(node->data, matchlen);
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rcu_assign_pointer(new_node->child[next_bit], node);
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rcu_assign_pointer(*slot, new_node);
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goto out;
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}
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im_node = lpm_trie_node_alloc(trie, NULL);
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if (!im_node) {
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ret = -ENOMEM;
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goto out;
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}
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im_node->prefixlen = matchlen;
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im_node->flags |= LPM_TREE_NODE_FLAG_IM;
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memcpy(im_node->data, node->data, trie->data_size);
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/* Now determine which child to install in which slot */
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if (extract_bit(key->data, matchlen)) {
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rcu_assign_pointer(im_node->child[0], node);
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rcu_assign_pointer(im_node->child[1], new_node);
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} else {
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rcu_assign_pointer(im_node->child[0], new_node);
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rcu_assign_pointer(im_node->child[1], node);
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}
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/* Finally, assign the intermediate node to the determined spot */
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rcu_assign_pointer(*slot, im_node);
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out:
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if (ret) {
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if (new_node)
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trie->n_entries--;
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kfree(new_node);
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kfree(im_node);
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}
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spin_unlock_irqrestore(&trie->lock, irq_flags);
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return ret;
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}
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|
|
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/* Called from syscall or from eBPF program */
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static int trie_delete_elem(struct bpf_map *map, void *_key)
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{
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struct lpm_trie *trie = container_of(map, struct lpm_trie, map);
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struct bpf_lpm_trie_key *key = _key;
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struct lpm_trie_node __rcu **trim, **trim2;
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struct lpm_trie_node *node, *parent;
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unsigned long irq_flags;
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unsigned int next_bit;
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size_t matchlen = 0;
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int ret = 0;
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if (key->prefixlen > trie->max_prefixlen)
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return -EINVAL;
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spin_lock_irqsave(&trie->lock, irq_flags);
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|
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/* Walk the tree looking for an exact key/length match and keeping
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* track of the path we traverse. We will need to know the node
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* we wish to delete, and the slot that points to the node we want
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* to delete. We may also need to know the nodes parent and the
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* slot that contains it.
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*/
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trim = &trie->root;
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trim2 = trim;
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parent = NULL;
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while ((node = rcu_dereference_protected(
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*trim, lockdep_is_held(&trie->lock)))) {
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matchlen = longest_prefix_match(trie, node, key);
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if (node->prefixlen != matchlen ||
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node->prefixlen == key->prefixlen)
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break;
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parent = node;
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trim2 = trim;
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next_bit = extract_bit(key->data, node->prefixlen);
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trim = &node->child[next_bit];
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}
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if (!node || node->prefixlen != key->prefixlen ||
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node->prefixlen != matchlen ||
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(node->flags & LPM_TREE_NODE_FLAG_IM)) {
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ret = -ENOENT;
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goto out;
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}
|
|
|
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trie->n_entries--;
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|
|
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/* If the node we are removing has two children, simply mark it
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* as intermediate and we are done.
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*/
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if (rcu_access_pointer(node->child[0]) &&
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rcu_access_pointer(node->child[1])) {
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node->flags |= LPM_TREE_NODE_FLAG_IM;
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goto out;
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}
|
|
|
|
/* If the parent of the node we are about to delete is an intermediate
|
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* node, and the deleted node doesn't have any children, we can delete
|
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* the intermediate parent as well and promote its other child
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* up the tree. Doing this maintains the invariant that all
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* intermediate nodes have exactly 2 children and that there are no
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* unnecessary intermediate nodes in the tree.
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*/
|
|
if (parent && (parent->flags & LPM_TREE_NODE_FLAG_IM) &&
|
|
!node->child[0] && !node->child[1]) {
|
|
if (node == rcu_access_pointer(parent->child[0]))
|
|
rcu_assign_pointer(
|
|
*trim2, rcu_access_pointer(parent->child[1]));
|
|
else
|
|
rcu_assign_pointer(
|
|
*trim2, rcu_access_pointer(parent->child[0]));
|
|
kfree_rcu(parent, rcu);
|
|
kfree_rcu(node, rcu);
|
|
goto out;
|
|
}
|
|
|
|
/* The node we are removing has either zero or one child. If there
|
|
* is a child, move it into the removed node's slot then delete
|
|
* the node. Otherwise just clear the slot and delete the node.
|
|
*/
|
|
if (node->child[0])
|
|
rcu_assign_pointer(*trim, rcu_access_pointer(node->child[0]));
|
|
else if (node->child[1])
|
|
rcu_assign_pointer(*trim, rcu_access_pointer(node->child[1]));
|
|
else
|
|
RCU_INIT_POINTER(*trim, NULL);
|
|
kfree_rcu(node, rcu);
|
|
|
|
out:
|
|
spin_unlock_irqrestore(&trie->lock, irq_flags);
|
|
|
|
return ret;
|
|
}
|
|
|
|
#define LPM_DATA_SIZE_MAX 256
|
|
#define LPM_DATA_SIZE_MIN 1
|
|
|
|
#define LPM_VAL_SIZE_MAX (KMALLOC_MAX_SIZE - LPM_DATA_SIZE_MAX - \
|
|
sizeof(struct lpm_trie_node))
|
|
#define LPM_VAL_SIZE_MIN 1
|
|
|
|
#define LPM_KEY_SIZE(X) (sizeof(struct bpf_lpm_trie_key) + (X))
|
|
#define LPM_KEY_SIZE_MAX LPM_KEY_SIZE(LPM_DATA_SIZE_MAX)
|
|
#define LPM_KEY_SIZE_MIN LPM_KEY_SIZE(LPM_DATA_SIZE_MIN)
|
|
|
|
#define LPM_CREATE_FLAG_MASK (BPF_F_NO_PREALLOC | BPF_F_NUMA_NODE | \
|
|
BPF_F_ACCESS_MASK)
|
|
|
|
static struct bpf_map *trie_alloc(union bpf_attr *attr)
|
|
{
|
|
struct lpm_trie *trie;
|
|
|
|
if (!bpf_capable())
|
|
return ERR_PTR(-EPERM);
|
|
|
|
/* check sanity of attributes */
|
|
if (attr->max_entries == 0 ||
|
|
!(attr->map_flags & BPF_F_NO_PREALLOC) ||
|
|
attr->map_flags & ~LPM_CREATE_FLAG_MASK ||
|
|
!bpf_map_flags_access_ok(attr->map_flags) ||
|
|
attr->key_size < LPM_KEY_SIZE_MIN ||
|
|
attr->key_size > LPM_KEY_SIZE_MAX ||
|
|
attr->value_size < LPM_VAL_SIZE_MIN ||
|
|
attr->value_size > LPM_VAL_SIZE_MAX)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
trie = kzalloc(sizeof(*trie), GFP_USER | __GFP_NOWARN | __GFP_ACCOUNT);
|
|
if (!trie)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
/* copy mandatory map attributes */
|
|
bpf_map_init_from_attr(&trie->map, attr);
|
|
trie->data_size = attr->key_size -
|
|
offsetof(struct bpf_lpm_trie_key, data);
|
|
trie->max_prefixlen = trie->data_size * 8;
|
|
|
|
spin_lock_init(&trie->lock);
|
|
|
|
return &trie->map;
|
|
}
|
|
|
|
static void trie_free(struct bpf_map *map)
|
|
{
|
|
struct lpm_trie *trie = container_of(map, struct lpm_trie, map);
|
|
struct lpm_trie_node __rcu **slot;
|
|
struct lpm_trie_node *node;
|
|
|
|
/* Always start at the root and walk down to a node that has no
|
|
* children. Then free that node, nullify its reference in the parent
|
|
* and start over.
|
|
*/
|
|
|
|
for (;;) {
|
|
slot = &trie->root;
|
|
|
|
for (;;) {
|
|
node = rcu_dereference_protected(*slot, 1);
|
|
if (!node)
|
|
goto out;
|
|
|
|
if (rcu_access_pointer(node->child[0])) {
|
|
slot = &node->child[0];
|
|
continue;
|
|
}
|
|
|
|
if (rcu_access_pointer(node->child[1])) {
|
|
slot = &node->child[1];
|
|
continue;
|
|
}
|
|
|
|
kfree(node);
|
|
RCU_INIT_POINTER(*slot, NULL);
|
|
break;
|
|
}
|
|
}
|
|
|
|
out:
|
|
kfree(trie);
|
|
}
|
|
|
|
static int trie_get_next_key(struct bpf_map *map, void *_key, void *_next_key)
|
|
{
|
|
struct lpm_trie_node *node, *next_node = NULL, *parent, *search_root;
|
|
struct lpm_trie *trie = container_of(map, struct lpm_trie, map);
|
|
struct bpf_lpm_trie_key *key = _key, *next_key = _next_key;
|
|
struct lpm_trie_node **node_stack = NULL;
|
|
int err = 0, stack_ptr = -1;
|
|
unsigned int next_bit;
|
|
size_t matchlen;
|
|
|
|
/* The get_next_key follows postorder. For the 4 node example in
|
|
* the top of this file, the trie_get_next_key() returns the following
|
|
* one after another:
|
|
* 192.168.0.0/24
|
|
* 192.168.1.0/24
|
|
* 192.168.128.0/24
|
|
* 192.168.0.0/16
|
|
*
|
|
* The idea is to return more specific keys before less specific ones.
|
|
*/
|
|
|
|
/* Empty trie */
|
|
search_root = rcu_dereference(trie->root);
|
|
if (!search_root)
|
|
return -ENOENT;
|
|
|
|
/* For invalid key, find the leftmost node in the trie */
|
|
if (!key || key->prefixlen > trie->max_prefixlen)
|
|
goto find_leftmost;
|
|
|
|
node_stack = kmalloc_array(trie->max_prefixlen,
|
|
sizeof(struct lpm_trie_node *),
|
|
GFP_ATOMIC | __GFP_NOWARN);
|
|
if (!node_stack)
|
|
return -ENOMEM;
|
|
|
|
/* Try to find the exact node for the given key */
|
|
for (node = search_root; node;) {
|
|
node_stack[++stack_ptr] = node;
|
|
matchlen = longest_prefix_match(trie, node, key);
|
|
if (node->prefixlen != matchlen ||
|
|
node->prefixlen == key->prefixlen)
|
|
break;
|
|
|
|
next_bit = extract_bit(key->data, node->prefixlen);
|
|
node = rcu_dereference(node->child[next_bit]);
|
|
}
|
|
if (!node || node->prefixlen != key->prefixlen ||
|
|
(node->flags & LPM_TREE_NODE_FLAG_IM))
|
|
goto find_leftmost;
|
|
|
|
/* The node with the exactly-matching key has been found,
|
|
* find the first node in postorder after the matched node.
|
|
*/
|
|
node = node_stack[stack_ptr];
|
|
while (stack_ptr > 0) {
|
|
parent = node_stack[stack_ptr - 1];
|
|
if (rcu_dereference(parent->child[0]) == node) {
|
|
search_root = rcu_dereference(parent->child[1]);
|
|
if (search_root)
|
|
goto find_leftmost;
|
|
}
|
|
if (!(parent->flags & LPM_TREE_NODE_FLAG_IM)) {
|
|
next_node = parent;
|
|
goto do_copy;
|
|
}
|
|
|
|
node = parent;
|
|
stack_ptr--;
|
|
}
|
|
|
|
/* did not find anything */
|
|
err = -ENOENT;
|
|
goto free_stack;
|
|
|
|
find_leftmost:
|
|
/* Find the leftmost non-intermediate node, all intermediate nodes
|
|
* have exact two children, so this function will never return NULL.
|
|
*/
|
|
for (node = search_root; node;) {
|
|
if (node->flags & LPM_TREE_NODE_FLAG_IM) {
|
|
node = rcu_dereference(node->child[0]);
|
|
} else {
|
|
next_node = node;
|
|
node = rcu_dereference(node->child[0]);
|
|
if (!node)
|
|
node = rcu_dereference(next_node->child[1]);
|
|
}
|
|
}
|
|
do_copy:
|
|
next_key->prefixlen = next_node->prefixlen;
|
|
memcpy((void *)next_key + offsetof(struct bpf_lpm_trie_key, data),
|
|
next_node->data, trie->data_size);
|
|
free_stack:
|
|
kfree(node_stack);
|
|
return err;
|
|
}
|
|
|
|
static int trie_check_btf(const struct bpf_map *map,
|
|
const struct btf *btf,
|
|
const struct btf_type *key_type,
|
|
const struct btf_type *value_type)
|
|
{
|
|
/* Keys must have struct bpf_lpm_trie_key embedded. */
|
|
return BTF_INFO_KIND(key_type->info) != BTF_KIND_STRUCT ?
|
|
-EINVAL : 0;
|
|
}
|
|
|
|
static int trie_map_btf_id;
|
|
const struct bpf_map_ops trie_map_ops = {
|
|
.map_meta_equal = bpf_map_meta_equal,
|
|
.map_alloc = trie_alloc,
|
|
.map_free = trie_free,
|
|
.map_get_next_key = trie_get_next_key,
|
|
.map_lookup_elem = trie_lookup_elem,
|
|
.map_update_elem = trie_update_elem,
|
|
.map_delete_elem = trie_delete_elem,
|
|
.map_check_btf = trie_check_btf,
|
|
.map_btf_name = "lpm_trie",
|
|
.map_btf_id = &trie_map_btf_id,
|
|
};
|