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 #include "../clone3/clone3_selftests.h" 21 22 #ifndef P_PIDFD 23 #define P_PIDFD 3 24 #endif 25 26 #ifndef CLONE_NEWTIME 27 #define CLONE_NEWTIME 0x00000080 28 #endif 29 30 #ifndef CLONE_PIDFD 31 #define CLONE_PIDFD 0x00001000 32 #endif 33 34 #ifndef __NR_pidfd_open 35 #define __NR_pidfd_open -1 36 #endif 37 38 #ifndef __NR_pidfd_send_signal 39 #define __NR_pidfd_send_signal -1 40 #endif 41 42 #ifndef __NR_clone3 43 #define __NR_clone3 -1 44 #endif 45 46 #ifndef __NR_pidfd_getfd 47 #define __NR_pidfd_getfd -1 48 #endif 49 50 #ifndef PIDFD_NONBLOCK 51 #define PIDFD_NONBLOCK O_NONBLOCK 52 #endif 53 54 /* 55 * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c 56 * That means, when it wraps around any pid < 300 will be skipped. 57 * So we need to use a pid > 300 in order to test recycling. 58 */ 59 #define PID_RECYCLE 1000 60 61 /* 62 * Define a few custom error codes for the child process to clearly indicate 63 * what is happening. This way we can tell the difference between a system 64 * error, a test error, etc. 65 */ 66 #define PIDFD_PASS 0 67 #define PIDFD_FAIL 1 68 #define PIDFD_ERROR 2 69 #define PIDFD_SKIP 3 70 #define PIDFD_XFAIL 4 71 72 static inline int sys_waitid(int which, pid_t pid, siginfo_t *info, int options) 73 { 74 return syscall(__NR_waitid, which, pid, info, options, NULL); 75 } 76 77 static inline int wait_for_pid(pid_t pid) 78 { 79 int status, ret; 80 81 again: 82 ret = waitpid(pid, &status, 0); 83 if (ret == -1) { 84 if (errno == EINTR) 85 goto again; 86 87 ksft_print_msg("waitpid returned -1, errno=%d\n", errno); 88 return -1; 89 } 90 91 if (!WIFEXITED(status)) { 92 ksft_print_msg( 93 "waitpid !WIFEXITED, WIFSIGNALED=%d, WTERMSIG=%d\n", 94 WIFSIGNALED(status), WTERMSIG(status)); 95 return -1; 96 } 97 98 ret = WEXITSTATUS(status); 99 return ret; 100 } 101 102 static inline int sys_pidfd_open(pid_t pid, unsigned int flags) 103 { 104 return syscall(__NR_pidfd_open, pid, flags); 105 } 106 107 static inline int sys_pidfd_send_signal(int pidfd, int sig, siginfo_t *info, 108 unsigned int flags) 109 { 110 return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags); 111 } 112 113 static inline int sys_pidfd_getfd(int pidfd, int fd, int flags) 114 { 115 return syscall(__NR_pidfd_getfd, pidfd, fd, flags); 116 } 117 118 static inline int sys_memfd_create(const char *name, unsigned int flags) 119 { 120 return syscall(__NR_memfd_create, name, flags); 121 } 122 123 static inline pid_t create_child(int *pidfd, unsigned flags) 124 { 125 struct __clone_args args = { 126 .flags = CLONE_PIDFD | flags, 127 .exit_signal = SIGCHLD, 128 .pidfd = ptr_to_u64(pidfd), 129 }; 130 131 return sys_clone3(&args, sizeof(struct __clone_args)); 132 } 133 134 static inline ssize_t read_nointr(int fd, void *buf, size_t count) 135 { 136 ssize_t ret; 137 138 do { 139 ret = read(fd, buf, count); 140 } while (ret < 0 && errno == EINTR); 141 142 return ret; 143 } 144 145 static inline ssize_t write_nointr(int fd, const void *buf, size_t count) 146 { 147 ssize_t ret; 148 149 do { 150 ret = write(fd, buf, count); 151 } while (ret < 0 && errno == EINTR); 152 153 return ret; 154 } 155 156 #endif /* __PIDFD_H */ 157