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
17 #include "../kselftest.h"
18
19 #ifndef P_PIDFD
20 #define P_PIDFD 3
21 #endif
22
23 #ifndef CLONE_PIDFD
24 #define CLONE_PIDFD 0x00001000
25 #endif
26
27 #ifndef __NR_pidfd_open
28 #define __NR_pidfd_open -1
29 #endif
30
31 #ifndef __NR_pidfd_send_signal
32 #define __NR_pidfd_send_signal -1
33 #endif
34
35 #ifndef __NR_clone3
36 #define __NR_clone3 -1
37 #endif
38
39 /*
40 * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c
41 * That means, when it wraps around any pid < 300 will be skipped.
42 * So we need to use a pid > 300 in order to test recycling.
43 */
44 #define PID_RECYCLE 1000
45
46 /*
47 * Define a few custom error codes for the child process to clearly indicate
48 * what is happening. This way we can tell the difference between a system
49 * error, a test error, etc.
50 */
51 #define PIDFD_PASS 0
52 #define PIDFD_FAIL 1
53 #define PIDFD_ERROR 2
54 #define PIDFD_SKIP 3
55 #define PIDFD_XFAIL 4
56
wait_for_pid(pid_t pid)57 int wait_for_pid(pid_t pid)
58 {
59 int status, ret;
60
61 again:
62 ret = waitpid(pid, &status, 0);
63 if (ret == -1) {
64 if (errno == EINTR)
65 goto again;
66
67 return -1;
68 }
69
70 if (!WIFEXITED(status))
71 return -1;
72
73 return WEXITSTATUS(status);
74 }
75
sys_pidfd_open(pid_t pid,unsigned int flags)76 static inline int sys_pidfd_open(pid_t pid, unsigned int flags)
77 {
78 return syscall(__NR_pidfd_open, pid, flags);
79 }
80
sys_pidfd_send_signal(int pidfd,int sig,siginfo_t * info,unsigned int flags)81 static inline int sys_pidfd_send_signal(int pidfd, int sig, siginfo_t *info,
82 unsigned int flags)
83 {
84 return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags);
85 }
86
87 #endif /* __PIDFD_H */
88