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
|
/*
* Copyright (c) 2021, Patrick Meyer <git@the-space.agency>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <fcntl.h>
#include <stdio.h>
#include <sys/ioctl.h>
#include <sys/ioctl_numbers.h>
#include <sys/kcov.h>
#include <sys/mman.h>
#include <unistd.h>
// Note: This program requires serenity to be built with the CMake build option
// ENABLE_KERNEL_COVERAGE_COLLECTION
int main(void)
{
constexpr size_t num_entries = 1024 * 100;
int fd = open("/dev/kcov0", O_RDWR);
if (fd == -1) {
perror("open");
return 1;
}
if (ioctl(fd, KCOV_SETBUFSIZE, num_entries) == -1) {
perror("ioctl: KCOV_SETBUFSIZE");
return 1;
}
kcov_pc_t* cover = (kcov_pc_t*)mmap(NULL, num_entries * KCOV_ENTRY_SIZE,
PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
if (cover == MAP_FAILED) {
perror("mmap");
return 1;
}
if (ioctl(fd, KCOV_ENABLE) == -1) {
perror("ioctl: KCOV_ENABLE");
return 1;
}
cover[0] = 0;
// Example syscall so we actually cover some kernel code.
getppid();
if (ioctl(fd, KCOV_DISABLE) == -1) {
perror("ioctl: KCOV_DISABLE");
return 1;
}
u64 cov_idx = cover[0];
for (size_t idx = 1; idx <= cov_idx; idx++)
printf("%p\n", (void*)cover[idx]);
if (munmap(const_cast<u64*>(cover), num_entries * KCOV_ENTRY_SIZE) == -1) {
perror("munmap");
return 1;
}
close(fd);
return 0;
}
|
