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/types.h>
16 #include <sys/wait.h>
17
18 #include "../kselftest.h"
19 #include "../clone3/clone3_selftests.h"
20
21 #ifndef P_PIDFD
22 #define P_PIDFD 3
23 #endif
24
25 #ifndef CLONE_NEWTIME
26 #define CLONE_NEWTIME 0x00000080
27 #endif
28
29 #ifndef CLONE_PIDFD
30 #define CLONE_PIDFD 0x00001000
31 #endif
32
33 #ifndef __NR_pidfd_open
34 #define __NR_pidfd_open -1
35 #endif
36
37 #ifndef __NR_pidfd_send_signal
38 #define __NR_pidfd_send_signal -1
39 #endif
40
41 #ifndef __NR_clone3
42 #define __NR_clone3 -1
43 #endif
44
45 #ifndef __NR_pidfd_getfd
46 #define __NR_pidfd_getfd -1
47 #endif
48
49 #ifndef PIDFD_NONBLOCK
50 #define PIDFD_NONBLOCK O_NONBLOCK
51 #endif
52
53 /*
54 * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c
55 * That means, when it wraps around any pid < 300 will be skipped.
56 * So we need to use a pid > 300 in order to test recycling.
57 */
58 #define PID_RECYCLE 1000
59
60 /*
61 * Define a few custom error codes for the child process to clearly indicate
62 * what is happening. This way we can tell the difference between a system
63 * error, a test error, etc.
64 */
65 #define PIDFD_PASS 0
66 #define PIDFD_FAIL 1
67 #define PIDFD_ERROR 2
68 #define PIDFD_SKIP 3
69 #define PIDFD_XFAIL 4
70
sys_waitid(int which,pid_t pid,siginfo_t * info,int options)71 static inline int sys_waitid(int which, pid_t pid, siginfo_t *info, int options)
72 {
73 return syscall(__NR_waitid, which, pid, info, options, NULL);
74 }
75
wait_for_pid(pid_t pid)76 static inline int wait_for_pid(pid_t pid)
77 {
78 int status, ret;
79
80 again:
81 ret = waitpid(pid, &status, 0);
82 if (ret == -1) {
83 if (errno == EINTR)
84 goto again;
85
86 ksft_print_msg("waitpid returned -1, errno=%d\n", errno);
87 return -1;
88 }
89
90 if (!WIFEXITED(status)) {
91 ksft_print_msg(
92 "waitpid !WIFEXITED, WIFSIGNALED=%d, WTERMSIG=%d\n",
93 WIFSIGNALED(status), WTERMSIG(status));
94 return -1;
95 }
96
97 ret = WEXITSTATUS(status);
98 return ret;
99 }
100
sys_pidfd_open(pid_t pid,unsigned int flags)101 static inline int sys_pidfd_open(pid_t pid, unsigned int flags)
102 {
103 return syscall(__NR_pidfd_open, pid, flags);
104 }
105
sys_pidfd_send_signal(int pidfd,int sig,siginfo_t * info,unsigned int flags)106 static inline int sys_pidfd_send_signal(int pidfd, int sig, siginfo_t *info,
107 unsigned int flags)
108 {
109 return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags);
110 }
111
sys_pidfd_getfd(int pidfd,int fd,int flags)112 static inline int sys_pidfd_getfd(int pidfd, int fd, int flags)
113 {
114 return syscall(__NR_pidfd_getfd, pidfd, fd, flags);
115 }
116
sys_memfd_create(const char * name,unsigned int flags)117 static inline int sys_memfd_create(const char *name, unsigned int flags)
118 {
119 return syscall(__NR_memfd_create, name, flags);
120 }
121
create_child(int * pidfd,unsigned flags)122 static inline pid_t create_child(int *pidfd, unsigned flags)
123 {
124 struct __clone_args args = {
125 .flags = CLONE_PIDFD | flags,
126 .exit_signal = SIGCHLD,
127 .pidfd = ptr_to_u64(pidfd),
128 };
129
130 return sys_clone3(&args, sizeof(struct __clone_args));
131 }
132
read_nointr(int fd,void * buf,size_t count)133 static inline ssize_t read_nointr(int fd, void *buf, size_t count)
134 {
135 ssize_t ret;
136
137 do {
138 ret = read(fd, buf, count);
139 } while (ret < 0 && errno == EINTR);
140
141 return ret;
142 }
143
write_nointr(int fd,const void * buf,size_t count)144 static inline ssize_t write_nointr(int fd, const void *buf, size_t count)
145 {
146 ssize_t ret;
147
148 do {
149 ret = write(fd, buf, count);
150 } while (ret < 0 && errno == EINTR);
151
152 return ret;
153 }
154
155 #endif /* __PIDFD_H */
156