summaryrefslogtreecommitdiffstats
path: root/samples/bpf/libbpf.c
blob: ff65044207384b908f511f48567e1fb57ec72982 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
/* eBPF mini library */
#include <stdlib.h>
#include <stdio.h>
#include <linux/unistd.h>
#include <unistd.h>
#include <string.h>
#include <linux/netlink.h>
#include <linux/bpf.h>
#include <errno.h>
#include "libbpf.h"

static __u64 ptr_to_u64(void *ptr)
{
	return (__u64) (unsigned long) ptr;
}

int bpf_create_map(enum bpf_map_type map_type, int key_size, int value_size,
		   int max_entries)
{
	union bpf_attr attr = {
		.map_type = map_type,
		.key_size = key_size,
		.value_size = value_size,
		.max_entries = max_entries
	};

	return syscall(__NR_bpf, BPF_MAP_CREATE, &attr, sizeof(attr));
}

int bpf_update_elem(int fd, void *key, void *value)
{
	union bpf_attr attr = {
		.map_fd = fd,
		.key = ptr_to_u64(key),
		.value = ptr_to_u64(value),
	};

	return syscall(__NR_bpf, BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
}

int bpf_lookup_elem(int fd, void *key, void *value)
{
	union bpf_attr attr = {
		.map_fd = fd,
		.key = ptr_to_u64(key),
		.value = ptr_to_u64(value),
	};

	return syscall(__NR_bpf, BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr));
}

int bpf_delete_elem(int fd, void *key)
{
	union bpf_attr attr = {
		.map_fd = fd,
		.key = ptr_to_u64(key),
	};

	return syscall(__NR_bpf, BPF_MAP_DELETE_ELEM, &attr, sizeof(attr));
}

int bpf_get_next_key(int fd, void *key, void *next_key)
{
	union bpf_attr attr = {
		.map_fd = fd,
		.key = ptr_to_u64(key),
		.next_key = ptr_to_u64(next_key),
	};

	return syscall(__NR_bpf, BPF_MAP_GET_NEXT_KEY, &attr, sizeof(attr));
}

#define ROUND_UP(x, n) (((x) + (n) - 1u) & ~((n) - 1u))

char bpf_log_buf[LOG_BUF_SIZE];

int bpf_prog_load(enum bpf_prog_type prog_type,
		  const struct bpf_insn *insns, int prog_len,
		  const char *license)
{
	union bpf_attr attr = {
		.prog_type = prog_type,
		.insns = ptr_to_u64((void *) insns),
		.insn_cnt = prog_len / sizeof(struct bpf_insn),
		.license = ptr_to_u64((void *) license),
		.log_buf = ptr_to_u64(bpf_log_buf),
		.log_size = LOG_BUF_SIZE,
		.log_level = 1,
	};

	bpf_log_buf[0] = 0;

	return syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr));
}
OpenPOWER on IntegriCloud