113 lines
2.8 KiB
C
113 lines
2.8 KiB
C
/*
|
|
* common eBPF ELF operations.
|
|
*
|
|
* Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
|
|
* Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
|
|
* Copyright (C) 2015 Huawei Inc.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation;
|
|
* version 2.1 of the License (not later!)
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this program; if not, see <http://www.gnu.org/licenses>
|
|
*/
|
|
|
|
#include <stdlib.h>
|
|
#include <memory.h>
|
|
#include <unistd.h>
|
|
#include <asm/unistd.h>
|
|
#include <linux/bpf.h>
|
|
#include "bpf.h"
|
|
|
|
/*
|
|
* When building perf, unistd.h is overrided. __NR_bpf is
|
|
* required to be defined explicitly.
|
|
*/
|
|
#ifndef __NR_bpf
|
|
# if defined(__i386__)
|
|
# define __NR_bpf 357
|
|
# elif defined(__x86_64__)
|
|
# define __NR_bpf 321
|
|
# elif defined(__aarch64__)
|
|
# define __NR_bpf 280
|
|
# else
|
|
# error __NR_bpf not defined. libbpf does not support your arch.
|
|
# endif
|
|
#endif
|
|
|
|
static __u64 ptr_to_u64(void *ptr)
|
|
{
|
|
return (__u64) (unsigned long) ptr;
|
|
}
|
|
|
|
static int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr,
|
|
unsigned int size)
|
|
{
|
|
return syscall(__NR_bpf, cmd, attr, size);
|
|
}
|
|
|
|
int bpf_create_map(enum bpf_map_type map_type, int key_size,
|
|
int value_size, int max_entries)
|
|
{
|
|
union bpf_attr attr;
|
|
|
|
memset(&attr, '\0', sizeof(attr));
|
|
|
|
attr.map_type = map_type;
|
|
attr.key_size = key_size;
|
|
attr.value_size = value_size;
|
|
attr.max_entries = max_entries;
|
|
|
|
return sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
|
|
}
|
|
|
|
int bpf_load_program(enum bpf_prog_type type, struct bpf_insn *insns,
|
|
size_t insns_cnt, char *license,
|
|
u32 kern_version, char *log_buf, size_t log_buf_sz)
|
|
{
|
|
int fd;
|
|
union bpf_attr attr;
|
|
|
|
bzero(&attr, sizeof(attr));
|
|
attr.prog_type = type;
|
|
attr.insn_cnt = (__u32)insns_cnt;
|
|
attr.insns = ptr_to_u64(insns);
|
|
attr.license = ptr_to_u64(license);
|
|
attr.log_buf = ptr_to_u64(NULL);
|
|
attr.log_size = 0;
|
|
attr.log_level = 0;
|
|
attr.kern_version = kern_version;
|
|
|
|
fd = sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
|
|
if (fd >= 0 || !log_buf || !log_buf_sz)
|
|
return fd;
|
|
|
|
/* Try again with log */
|
|
attr.log_buf = ptr_to_u64(log_buf);
|
|
attr.log_size = log_buf_sz;
|
|
attr.log_level = 1;
|
|
log_buf[0] = 0;
|
|
return sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
|
|
}
|
|
|
|
int bpf_map_update_elem(int fd, void *key, void *value,
|
|
u64 flags)
|
|
{
|
|
union bpf_attr attr;
|
|
|
|
bzero(&attr, sizeof(attr));
|
|
attr.map_fd = fd;
|
|
attr.key = ptr_to_u64(key);
|
|
attr.value = ptr_to_u64(value);
|
|
attr.flags = flags;
|
|
|
|
return sys_bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
|
|
}
|