Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2
3#ifndef __PIDFD_H
4#define __PIDFD_H
5
6#define _GNU_SOURCE
7#include <errno.h>
8#include <fcntl.h>
9#include <sched.h>
10#include <signal.h>
11#include <stdio.h>
12#include <stdlib.h>
13#include <string.h>
14#include <syscall.h>
15#include <sys/mount.h>
16#include <sys/types.h>
17#include <sys/wait.h>
18
19#include "../kselftest.h"
20
21#ifndef P_PIDFD
22#define P_PIDFD 3
23#endif
24
25#ifndef CLONE_PIDFD
26#define CLONE_PIDFD 0x00001000
27#endif
28
29#ifndef __NR_pidfd_open
30#define __NR_pidfd_open -1
31#endif
32
33#ifndef __NR_pidfd_send_signal
34#define __NR_pidfd_send_signal -1
35#endif
36
37#ifndef __NR_clone3
38#define __NR_clone3 -1
39#endif
40
41#ifndef __NR_pidfd_getfd
42#define __NR_pidfd_getfd -1
43#endif
44
45/*
46 * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c
47 * That means, when it wraps around any pid < 300 will be skipped.
48 * So we need to use a pid > 300 in order to test recycling.
49 */
50#define PID_RECYCLE 1000
51
52/*
53 * Define a few custom error codes for the child process to clearly indicate
54 * what is happening. This way we can tell the difference between a system
55 * error, a test error, etc.
56 */
57#define PIDFD_PASS 0
58#define PIDFD_FAIL 1
59#define PIDFD_ERROR 2
60#define PIDFD_SKIP 3
61#define PIDFD_XFAIL 4
62
63int wait_for_pid(pid_t pid)
64{
65 int status, ret;
66
67again:
68 ret = waitpid(pid, &status, 0);
69 if (ret == -1) {
70 if (errno == EINTR)
71 goto again;
72
73 return -1;
74 }
75
76 if (!WIFEXITED(status))
77 return -1;
78
79 return WEXITSTATUS(status);
80}
81
82static inline int sys_pidfd_open(pid_t pid, unsigned int flags)
83{
84 return syscall(__NR_pidfd_open, pid, flags);
85}
86
87static inline int sys_pidfd_send_signal(int pidfd, int sig, siginfo_t *info,
88 unsigned int flags)
89{
90 return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags);
91}
92
93static inline int sys_pidfd_getfd(int pidfd, int fd, int flags)
94{
95 return syscall(__NR_pidfd_getfd, pidfd, fd, flags);
96}
97
98#endif /* __PIDFD_H */