Linux system calls

In modern operating systems, the kernel provides a set of interfaces for user processes to interact with the kernel. These interfaces give applications limited access to hardware devices, provide mechanisms for creating new processes and communicate with existing processes, and provide the ability to request other resources of the operating system.

These interfaces play the role of messengers between the application and the kernel, the application makes various requests, and the kernel is responsible for fulfilling these requests (or returning an error if they cannot be fulfilled). In fact, these interfaces are mainly provided to ensure the stability and reliability of the system and to avoid arbitrary behavior of applications.

communicate with the kernel

System calls add an intermediate layer between user-space processes and hardware devices. This layer has three main functions.

First, it provides an abstract interface to the hardware for user space. For example, when a file needs to be read or written, the application can ignore the disk type and medium, or even the type of the file system where the file is located.

Second, system calls ensure the stability and security of the system. Acting as a middleman between the hardware device and the application, the kernel can arbitrate what access needs to be done based on permissions, user type, and a few other rules. For example, this prevents applications from using hardware devices incorrectly, stealing resources from other processes, or doing other things that harm the system.

Third, each process runs in a virtual system, and providing such a layer of common interface between user space and the rest of the system is also for this consideration. If the application has free access to the hardware and the kernel knows nothing about it, multitasking and virtual memory are almost impossible to achieve, and certainly not good stability and security.

In Linux, system calls are the only means for user space to access the kernel; except for exceptions and traps, they are the only legal entry to the kernel. In fact, other methods like device files and /proc are ultimately accessed through system calls. Interestingly, Linux provides far fewer system calls than most operating systems.

To access a system call (often called a syscall in Linux), it is usually done through a function call defined in the C library. They usually need to define zero, one or several parameters (inputs) and may have some side effects, such as writing a file or copying data to a given pointer. System calls also pass a long return value to indicate success or error. Usually, but not always, a negative return value is used to indicate errors. Returning a value of 0 usually (but still not absolute) indicates success. When an error occurs in the system call, the C library will write the error code to the errno global variable. This variable can be translated into a user-understandable error string by calling the perror() library function.

In Linux, each system call is assigned a system call number. In this way, system calls can be associated with this unique number. When a user-space process executes a system call, the system call number is used to indicate which system call to execute; the process does not mention the name of the system call.

System call description

asmlinkage qualifier, which is a pragma that tells the compiler to extract only the function's arguments from the stack.

The function returns long. In order to ensure compatibility between 32-bit and 64-bit systems, system calls have different return value types in user space and kernel space, int in user space and long in kernel space.

Assuming that the system call is defined as sys_ioctl in kernel space, then the user space interface of the system call is ioctl

Linux kernel-5.18.8 has 440 system calls. These system calls pay attention to generality. Once fixed, they are rarely modified to ensure the stability and compatibility of the Linux system.

/include/linux/syscalls.h

#ifndef CONFIG_ARCH_HAS_SYSCALL_WRAPPER
asmlinkage long sys_io_setup(unsigned nr_reqs, aio_context_t __user *ctx);
asmlinkage long sys_io_destroy(aio_context_t ctx);
asmlinkage long sys_io_submit(aio_context_t, long,
   struct iocb __user * __user *);
asmlinkage long sys_io_cancel(aio_context_t ctx_id, struct iocb __user *iocb,
         struct io_event __user *result);
asmlinkage long sys_io_getevents(aio_context_t ctx_id,
    long min_nr,
    long nr,
    struct io_event __user *events,
    struct __kernel_timespec __user *timeout);
asmlinkage long sys_io_getevents_time32(__u32 ctx_id,
    __s32 min_nr,
    __s32 nr,
    struct io_event __user *events,
    struct old_timespec32 __user *timeout);
asmlinkage long sys_io_pgetevents(aio_context_t ctx_id,
    long min_nr,
    long nr,
    struct io_event __user *events,
    struct __kernel_timespec __user *timeout,
    const struct __aio_sigset *sig);
asmlinkage long sys_io_pgetevents_time32(aio_context_t ctx_id,
    long min_nr,
    long nr,
    struct io_event __user *events,
    struct old_timespec32 __user *timeout,
    const struct __aio_sigset *sig);
asmlinkage long sys_io_uring_setup(u32 entries,
    struct io_uring_params __user *p);
asmlinkage long sys_io_uring_enter(unsigned int fd, u32 to_submit,
    u32 min_complete, u32 flags,
    const void __user *argp, size_t argsz);
asmlinkage long sys_io_uring_register(unsigned int fd, unsigned int op,
    void __user *arg, unsigned int nr_args);

/* fs/xattr.c */
asmlinkage long sys_setxattr(const char __user *path, const char __user *name,
        const void __user *value, size_t size, int flags);
asmlinkage long sys_lsetxattr(const char __user *path, const char __user *name,
         const void __user *value, size_t size, int flags);
asmlinkage long sys_fsetxattr(int fd, const char __user *name,
         const void __user *value, size_t size, int flags);
asmlinkage long sys_getxattr(const char __user *path, const char __user *name,
        void __user *value, size_t size);
asmlinkage long sys_lgetxattr(const char __user *path, const char __user *name,
         void __user *value, size_t size);
asmlinkage long sys_fgetxattr(int fd, const char __user *name,
         void __user *value, size_t size);
asmlinkage long sys_listxattr(const char __user *path, char __user *list,
         size_t size);
asmlinkage long sys_llistxattr(const char __user *path, char __user *list,
          size_t size);
asmlinkage long sys_flistxattr(int fd, char __user *list, size_t size);
asmlinkage long sys_removexattr(const char __user *path,
    const char __user *name);
asmlinkage long sys_lremovexattr(const char __user *path,
     const char __user *name);
asmlinkage long sys_fremovexattr(int fd, const char __user *name);

/* fs/dcache.c */
asmlinkage long sys_getcwd(char __user *buf, unsigned long size);

/* fs/cookies.c */
asmlinkage long sys_lookup_dcookie(u64 cookie64, char __user *buf, size_t len);

/* fs/eventfd.c */
asmlinkage long sys_eventfd2(unsigned int count, int flags);

/* fs/eventpoll.c */
asmlinkage long sys_epoll_create1(int flags);
asmlinkage long sys_epoll_ctl(int epfd, int op, int fd,
    struct epoll_event __user *event);
asmlinkage long sys_epoll_pwait(int epfd, struct epoll_event __user *events,
    int maxevents, int timeout,
    const sigset_t __user *sigmask,
    size_t sigsetsize);
asmlinkage long sys_epoll_pwait2(int epfd, struct epoll_event __user *events,
     int maxevents,
     const struct __kernel_timespec __user *timeout,
     const sigset_t __user *sigmask,
     size_t sigsetsize);

/* fs/fcntl.c */
asmlinkage long sys_dup(unsigned int fildes);
asmlinkage long sys_dup3(unsigned int oldfd, unsigned int newfd, int flags);
asmlinkage long sys_fcntl(unsigned int fd, unsigned int cmd, unsigned long arg);
#if BITS_PER_LONG == 32
asmlinkage long sys_fcntl64(unsigned int fd,
    unsigned int cmd, unsigned long arg);
#endif

/* fs/inotify_user.c */
asmlinkage long sys_inotify_init1(int flags);
asmlinkage long sys_inotify_add_watch(int fd, const char __user *path,
     u32 mask);
asmlinkage long sys_inotify_rm_watch(int fd, __s32 wd);

/* fs/ioctl.c */
asmlinkage long sys_ioctl(unsigned int fd, unsigned int cmd,
    unsigned long arg);

/* fs/ioprio.c */
asmlinkage long sys_ioprio_set(int which, int who, int ioprio);
asmlinkage long sys_ioprio_get(int which, int who);

/* fs/locks.c */
asmlinkage long sys_flock(unsigned int fd, unsigned int cmd);

/* fs/namei.c */
asmlinkage long sys_mknodat(int dfd, const char __user * filename, umode_t mode,
       unsigned dev);
asmlinkage long sys_mkdirat(int dfd, const char __user * pathname, umode_t mode);
asmlinkage long sys_unlinkat(int dfd, const char __user * pathname, int flag);
asmlinkage long sys_symlinkat(const char __user * oldname,
         int newdfd, const char __user * newname);
asmlinkage long sys_linkat(int olddfd, const char __user *oldname,
      int newdfd, const char __user *newname, int flags);
asmlinkage long sys_renameat(int olddfd, const char __user * oldname,
        int newdfd, const char __user * newname);

/* fs/namespace.c */
asmlinkage long sys_umount(char __user *name, int flags);
asmlinkage long sys_mount(char __user *dev_name, char __user *dir_name,
    char __user *type, unsigned long flags,
    void __user *data);
asmlinkage long sys_pivot_root(const char __user *new_root,
    const char __user *put_old);

/* fs/nfsctl.c */

/* fs/open.c */
asmlinkage long sys_statfs(const char __user * path,
    struct statfs __user *buf);
asmlinkage long sys_statfs64(const char __user *path, size_t sz,
    struct statfs64 __user *buf);
asmlinkage long sys_fstatfs(unsigned int fd, struct statfs __user *buf);
asmlinkage long sys_fstatfs64(unsigned int fd, size_t sz,
    struct statfs64 __user *buf);
asmlinkage long sys_truncate(const char __user *path, long length);
asmlinkage long sys_ftruncate(unsigned int fd, unsigned long length);
#if BITS_PER_LONG == 32
asmlinkage long sys_truncate64(const char __user *path, loff_t length);
asmlinkage long sys_ftruncate64(unsigned int fd, loff_t length);
#endif
asmlinkage long sys_fallocate(int fd, int mode, loff_t offset, loff_t len);
asmlinkage long sys_faccessat(int dfd, const char __user *filename, int mode);
asmlinkage long sys_faccessat2(int dfd, const char __user *filename, int mode,
          int flags);
asmlinkage long sys_chdir(const char __user *filename);
asmlinkage long sys_fchdir(unsigned int fd);
asmlinkage long sys_chroot(const char __user *filename);
asmlinkage long sys_fchmod(unsigned int fd, umode_t mode);
asmlinkage long sys_fchmodat(int dfd, const char __user * filename,
        umode_t mode);
asmlinkage long sys_fchownat(int dfd, const char __user *filename, uid_t user,
        gid_t group, int flag);
asmlinkage long sys_fchown(unsigned int fd, uid_t user, gid_t group);
asmlinkage long sys_openat(int dfd, const char __user *filename, int flags,
      umode_t mode);
asmlinkage long sys_openat2(int dfd, const char __user *filename,
       struct open_how *how, size_t size);
asmlinkage long sys_close(unsigned int fd);
asmlinkage long sys_close_range(unsigned int fd, unsigned int max_fd,
    unsigned int flags);
asmlinkage long sys_vhangup(void);

/* fs/pipe.c */
asmlinkage long sys_pipe2(int __user *fildes, int flags);

/* fs/quota.c */
asmlinkage long sys_quotactl(unsigned int cmd, const char __user *special,
    qid_t id, void __user *addr);
asmlinkage long sys_quotactl_fd(unsigned int fd, unsigned int cmd, qid_t id,
    void __user *addr);

/* fs/readdir.c */
asmlinkage long sys_getdents64(unsigned int fd,
    struct linux_dirent64 __user *dirent,
    unsigned int count);

/* fs/read_write.c */
asmlinkage long sys_llseek(unsigned int fd, unsigned long offset_high,
   unsigned long offset_low, loff_t __user *result,
   unsigned int whence);
asmlinkage long sys_lseek(unsigned int fd, off_t offset,
     unsigned int whence);
asmlinkage long sys_read(unsigned int fd, char __user *buf, size_t count);
asmlinkage long sys_write(unsigned int fd, const char __user *buf,
     size_t count);
asmlinkage long sys_readv(unsigned long fd,
     const struct iovec __user *vec,
     unsigned long vlen);
asmlinkage long sys_writev(unsigned long fd,
      const struct iovec __user *vec,
      unsigned long vlen);
asmlinkage long sys_pread64(unsigned int fd, char __user *buf,
       size_t count, loff_t pos);
asmlinkage long sys_pwrite64(unsigned int fd, const char __user *buf,
        size_t count, loff_t pos);
asmlinkage long sys_preadv(unsigned long fd, const struct iovec __user *vec,
      unsigned long vlen, unsigned long pos_l, unsigned long pos_h);
asmlinkage long sys_pwritev(unsigned long fd, const struct iovec __user *vec,
       unsigned long vlen, unsigned long pos_l, unsigned long pos_h);

/* fs/sendfile.c */
asmlinkage long sys_sendfile64(int out_fd, int in_fd,
          loff_t __user *offset, size_t count);

/* fs/select.c */
asmlinkage long sys_pselect6(int, fd_set __user *, fd_set __user *,
        fd_set __user *, struct __kernel_timespec __user *,
        void __user *);
asmlinkage long sys_pselect6_time32(int, fd_set __user *, fd_set __user *,
        fd_set __user *, struct old_timespec32 __user *,
        void __user *);
asmlinkage long sys_ppoll(struct pollfd __user *, unsigned int,
     struct __kernel_timespec __user *, const sigset_t __user *,
     size_t);
asmlinkage long sys_ppoll_time32(struct pollfd __user *, unsigned int,
     struct old_timespec32 __user *, const sigset_t __user *,
     size_t);

/* fs/signalfd.c */
asmlinkage long sys_signalfd4(int ufd, sigset_t __user *user_mask, size_t sizemask, int flags);

/* fs/splice.c */
asmlinkage long sys_vmsplice(int fd, const struct iovec __user *iov,
        unsigned long nr_segs, unsigned int flags);
asmlinkage long sys_splice(int fd_in, loff_t __user *off_in,
      int fd_out, loff_t __user *off_out,
      size_t len, unsigned int flags);
asmlinkage long sys_tee(int fdin, int fdout, size_t len, unsigned int flags);

/* fs/stat.c */
asmlinkage long sys_readlinkat(int dfd, const char __user *path, char __user *buf,
          int bufsiz);
asmlinkage long sys_newfstatat(int dfd, const char __user *filename,
          struct stat __user *statbuf, int flag);
asmlinkage long sys_newfstat(unsigned int fd, struct stat __user *statbuf);
#if defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64)
asmlinkage long sys_fstat64(unsigned long fd, struct stat64 __user *statbuf);
asmlinkage long sys_fstatat64(int dfd, const char __user *filename,
          struct stat64 __user *statbuf, int flag);
#endif

/* fs/sync.c */
asmlinkage long sys_sync(void);
asmlinkage long sys_fsync(unsigned int fd);
asmlinkage long sys_fdatasync(unsigned int fd);
asmlinkage long sys_sync_file_range2(int fd, unsigned int flags,
         loff_t offset, loff_t nbytes);
asmlinkage long sys_sync_file_range(int fd, loff_t offset, loff_t nbytes,
     unsigned int flags);

/* fs/timerfd.c */
asmlinkage long sys_timerfd_create(int clockid, int flags);
asmlinkage long sys_timerfd_settime(int ufd, int flags,
        const struct __kernel_itimerspec __user *utmr,
        struct __kernel_itimerspec __user *otmr);
asmlinkage long sys_timerfd_gettime(int ufd, struct __kernel_itimerspec __user *otmr);
asmlinkage long sys_timerfd_gettime32(int ufd,
       struct old_itimerspec32 __user *otmr);
asmlinkage long sys_timerfd_settime32(int ufd, int flags,
       const struct old_itimerspec32 __user *utmr,
       struct old_itimerspec32 __user *otmr);

/* fs/utimes.c */
asmlinkage long sys_utimensat(int dfd, const char __user *filename,
    struct __kernel_timespec __user *utimes,
    int flags);
asmlinkage long sys_utimensat_time32(unsigned int dfd,
    const char __user *filename,
    struct old_timespec32 __user *t, int flags);

/* kernel/acct.c */
asmlinkage long sys_acct(const char __user *name);

/* kernel/capability.c */
asmlinkage long sys_capget(cap_user_header_t header,
    cap_user_data_t dataptr);
asmlinkage long sys_capset(cap_user_header_t header,
    const cap_user_data_t data);

/* kernel/exec_domain.c */
asmlinkage long sys_personality(unsigned int personality);

/* kernel/exit.c */
asmlinkage long sys_exit(int error_code);
asmlinkage long sys_exit_group(int error_code);
asmlinkage long sys_waitid(int which, pid_t pid,
      struct siginfo __user *infop,
      int options, struct rusage __user *ru);

/* kernel/fork.c */
asmlinkage long sys_set_tid_address(int __user *tidptr);
asmlinkage long sys_unshare(unsigned long unshare_flags);

/* kernel/futex/syscalls.c */
asmlinkage long sys_futex(u32 __user *uaddr, int op, u32 val,
     const struct __kernel_timespec __user *utime,
     u32 __user *uaddr2, u32 val3);
asmlinkage long sys_futex_time32(u32 __user *uaddr, int op, u32 val,
     const struct old_timespec32 __user *utime,
     u32 __user *uaddr2, u32 val3);
asmlinkage long sys_get_robust_list(int pid,
        struct robust_list_head __user * __user *head_ptr,
        size_t __user *len_ptr);
asmlinkage long sys_set_robust_list(struct robust_list_head __user *head,
        size_t len);

asmlinkage long sys_futex_waitv(struct futex_waitv *waiters,
    unsigned int nr_futexes, unsigned int flags,
    struct __kernel_timespec __user *timeout, clockid_t clockid);

/* kernel/hrtimer.c */
asmlinkage long sys_nanosleep(struct __kernel_timespec __user *rqtp,
         struct __kernel_timespec __user *rmtp);
asmlinkage long sys_nanosleep_time32(struct old_timespec32 __user *rqtp,
         struct old_timespec32 __user *rmtp);

/* kernel/itimer.c */
asmlinkage long sys_getitimer(int which, struct __kernel_old_itimerval __user *value);
asmlinkage long sys_setitimer(int which,
    struct __kernel_old_itimerval __user *value,
    struct __kernel_old_itimerval __user *ovalue);

/* kernel/kexec.c */
asmlinkage long sys_kexec_load(unsigned long entry, unsigned long nr_segments,
    struct kexec_segment __user *segments,
    unsigned long flags);

/* kernel/module.c */
asmlinkage long sys_init_module(void __user *umod, unsigned long len,
    const char __user *uargs);
asmlinkage long sys_delete_module(const char __user *name_user,
    unsigned int flags);

/* kernel/posix-timers.c */
asmlinkage long sys_timer_create(clockid_t which_clock,
     struct sigevent __user *timer_event_spec,
     timer_t __user * created_timer_id);
asmlinkage long sys_timer_gettime(timer_t timer_id,
    struct __kernel_itimerspec __user *setting);
asmlinkage long sys_timer_getoverrun(timer_t timer_id);
asmlinkage long sys_timer_settime(timer_t timer_id, int flags,
    const struct __kernel_itimerspec __user *new_setting,
    struct __kernel_itimerspec __user *old_setting);
asmlinkage long sys_timer_delete(timer_t timer_id);
asmlinkage long sys_clock_settime(clockid_t which_clock,
    const struct __kernel_timespec __user *tp);
asmlinkage long sys_clock_gettime(clockid_t which_clock,
    struct __kernel_timespec __user *tp);
asmlinkage long sys_clock_getres(clockid_t which_clock,
    struct __kernel_timespec __user *tp);
asmlinkage long sys_clock_nanosleep(clockid_t which_clock, int flags,
    const struct __kernel_timespec __user *rqtp,
    struct __kernel_timespec __user *rmtp);
asmlinkage long sys_timer_gettime32(timer_t timer_id,
     struct old_itimerspec32 __user *setting);
asmlinkage long sys_timer_settime32(timer_t timer_id, int flags,
      struct old_itimerspec32 __user *new,
      struct old_itimerspec32 __user *old);
asmlinkage long sys_clock_settime32(clockid_t which_clock,
    struct old_timespec32 __user *tp);
asmlinkage long sys_clock_gettime32(clockid_t which_clock,
    struct old_timespec32 __user *tp);
asmlinkage long sys_clock_getres_time32(clockid_t which_clock,
    struct old_timespec32 __user *tp);
asmlinkage long sys_clock_nanosleep_time32(clockid_t which_clock, int flags,
    struct old_timespec32 __user *rqtp,
    struct old_timespec32 __user *rmtp);

/* kernel/printk.c */
asmlinkage long sys_syslog(int type, char __user *buf, int len);

/* kernel/ptrace.c */
asmlinkage long sys_ptrace(long request, long pid, unsigned long addr,
      unsigned long data);
/* kernel/sched/core.c */

asmlinkage long sys_sched_setparam(pid_t pid,
     struct sched_param __user *param);
asmlinkage long sys_sched_setscheduler(pid_t pid, int policy,
     struct sched_param __user *param);
asmlinkage long sys_sched_getscheduler(pid_t pid);
asmlinkage long sys_sched_getparam(pid_t pid,
     struct sched_param __user *param);
asmlinkage long sys_sched_setaffinity(pid_t pid, unsigned int len,
     unsigned long __user *user_mask_ptr);
asmlinkage long sys_sched_getaffinity(pid_t pid, unsigned int len,
     unsigned long __user *user_mask_ptr);
asmlinkage long sys_sched_yield(void);
asmlinkage long sys_sched_get_priority_max(int policy);
asmlinkage long sys_sched_get_priority_min(int policy);
asmlinkage long sys_sched_rr_get_interval(pid_t pid,
    struct __kernel_timespec __user *interval);
asmlinkage long sys_sched_rr_get_interval_time32(pid_t pid,
       struct old_timespec32 __user *interval);

/* kernel/signal.c */
asmlinkage long sys_restart_syscall(void);
asmlinkage long sys_kill(pid_t pid, int sig);
asmlinkage long sys_tkill(pid_t pid, int sig);
asmlinkage long sys_tgkill(pid_t tgid, pid_t pid, int sig);
asmlinkage long sys_sigaltstack(const struct sigaltstack __user *uss,
    struct sigaltstack __user *uoss);
asmlinkage long sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize);
#ifndef CONFIG_ODD_RT_SIGACTION
asmlinkage long sys_rt_sigaction(int,
     const struct sigaction __user *,
     struct sigaction __user *,
     size_t);
#endif
asmlinkage long sys_rt_sigprocmask(int how, sigset_t __user *set,
    sigset_t __user *oset, size_t sigsetsize);
asmlinkage long sys_rt_sigpending(sigset_t __user *set, size_t sigsetsize);
asmlinkage long sys_rt_sigtimedwait(const sigset_t __user *uthese,
    siginfo_t __user *uinfo,
    const struct __kernel_timespec __user *uts,
    size_t sigsetsize);
asmlinkage long sys_rt_sigtimedwait_time32(const sigset_t __user *uthese,
    siginfo_t __user *uinfo,
    const struct old_timespec32 __user *uts,
    size_t sigsetsize);
asmlinkage long sys_rt_sigqueueinfo(pid_t pid, int sig, siginfo_t __user *uinfo);

/* kernel/sys.c */
asmlinkage long sys_setpriority(int which, int who, int niceval);
asmlinkage long sys_getpriority(int which, int who);
asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd,
    void __user *arg);
asmlinkage long sys_setregid(gid_t rgid, gid_t egid);
asmlinkage long sys_setgid(gid_t gid);
asmlinkage long sys_setreuid(uid_t ruid, uid_t euid);
asmlinkage long sys_setuid(uid_t uid);
asmlinkage long sys_setresuid(uid_t ruid, uid_t euid, uid_t suid);
asmlinkage long sys_getresuid(uid_t __user *ruid, uid_t __user *euid, uid_t __user *suid);
asmlinkage long sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid);
asmlinkage long sys_getresgid(gid_t __user *rgid, gid_t __user *egid, gid_t __user *sgid);
asmlinkage long sys_setfsuid(uid_t uid);
asmlinkage long sys_setfsgid(gid_t gid);
asmlinkage long sys_times(struct tms __user *tbuf);
asmlinkage long sys_setpgid(pid_t pid, pid_t pgid);
asmlinkage long sys_getpgid(pid_t pid);
asmlinkage long sys_getsid(pid_t pid);
asmlinkage long sys_setsid(void);
asmlinkage long sys_getgroups(int gidsetsize, gid_t __user *grouplist);
asmlinkage long sys_setgroups(int gidsetsize, gid_t __user *grouplist);
asmlinkage long sys_newuname(struct new_utsname __user *name);
asmlinkage long sys_sethostname(char __user *name, int len);
asmlinkage long sys_setdomainname(char __user *name, int len);
asmlinkage long sys_getrlimit(unsigned int resource,
    struct rlimit __user *rlim);
asmlinkage long sys_setrlimit(unsigned int resource,
    struct rlimit __user *rlim);
asmlinkage long sys_getrusage(int who, struct rusage __user *ru);
asmlinkage long sys_umask(int mask);
asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3,
   unsigned long arg4, unsigned long arg5);
asmlinkage long sys_getcpu(unsigned __user *cpu, unsigned __user *node, struct getcpu_cache __user *cache);

/* kernel/time.c */
asmlinkage long sys_gettimeofday(struct __kernel_old_timeval __user *tv,
    struct timezone __user *tz);
asmlinkage long sys_settimeofday(struct __kernel_old_timeval __user *tv,
    struct timezone __user *tz);
asmlinkage long sys_adjtimex(struct __kernel_timex __user *txc_p);
asmlinkage long sys_adjtimex_time32(struct old_timex32 __user *txc_p);

/* kernel/sys.c */
asmlinkage long sys_getpid(void);
asmlinkage long sys_getppid(void);
asmlinkage long sys_getuid(void);
asmlinkage long sys_geteuid(void);
asmlinkage long sys_getgid(void);
asmlinkage long sys_getegid(void);
asmlinkage long sys_gettid(void);
asmlinkage long sys_sysinfo(struct sysinfo __user *info);

/* ipc/mqueue.c */
asmlinkage long sys_mq_open(const char __user *name, int oflag, umode_t mode, struct mq_attr __user *attr);
asmlinkage long sys_mq_unlink(const char __user *name);
asmlinkage long sys_mq_timedsend(mqd_t mqdes, const char __user *msg_ptr, size_t msg_len, unsigned int msg_prio, const struct __kernel_timespec __user *abs_timeout);
asmlinkage long sys_mq_timedreceive(mqd_t mqdes, char __user *msg_ptr, size_t msg_len, unsigned int __user *msg_prio, const struct __kernel_timespec __user *abs_timeout);
asmlinkage long sys_mq_notify(mqd_t mqdes, const struct sigevent __user *notification);
asmlinkage long sys_mq_getsetattr(mqd_t mqdes, const struct mq_attr __user *mqstat, struct mq_attr __user *omqstat);
asmlinkage long sys_mq_timedreceive_time32(mqd_t mqdes,
   char __user *u_msg_ptr,
   unsigned int msg_len, unsigned int __user *u_msg_prio,
   const struct old_timespec32 __user *u_abs_timeout);
asmlinkage long sys_mq_timedsend_time32(mqd_t mqdes,
   const char __user *u_msg_ptr,
   unsigned int msg_len, unsigned int msg_prio,
   const struct old_timespec32 __user *u_abs_timeout);

/* ipc/msg.c */
asmlinkage long sys_msgget(key_t key, int msgflg);
asmlinkage long sys_old_msgctl(int msqid, int cmd, struct msqid_ds __user *buf);
asmlinkage long sys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf);
asmlinkage long sys_msgrcv(int msqid, struct msgbuf __user *msgp,
    size_t msgsz, long msgtyp, int msgflg);
asmlinkage long sys_msgsnd(int msqid, struct msgbuf __user *msgp,
    size_t msgsz, int msgflg);

/* ipc/sem.c */
asmlinkage long sys_semget(key_t key, int nsems, int semflg);
asmlinkage long sys_semctl(int semid, int semnum, int cmd, unsigned long arg);
asmlinkage long sys_old_semctl(int semid, int semnum, int cmd, unsigned long arg);
asmlinkage long sys_semtimedop(int semid, struct sembuf __user *sops,
    unsigned nsops,
    const struct __kernel_timespec __user *timeout);
asmlinkage long sys_semtimedop_time32(int semid, struct sembuf __user *sops,
    unsigned nsops,
    const struct old_timespec32 __user *timeout);
asmlinkage long sys_semop(int semid, struct sembuf __user *sops,
    unsigned nsops);

/* ipc/shm.c */
asmlinkage long sys_shmget(key_t key, size_t size, int flag);
asmlinkage long sys_old_shmctl(int shmid, int cmd, struct shmid_ds __user *buf);
asmlinkage long sys_shmctl(int shmid, int cmd, struct shmid_ds __user *buf);
asmlinkage long sys_shmat(int shmid, char __user *shmaddr, int shmflg);
asmlinkage long sys_shmdt(char __user *shmaddr);

/* net/socket.c */
asmlinkage long sys_socket(int, int, int);
asmlinkage long sys_socketpair(int, int, int, int __user *);
asmlinkage long sys_bind(int, struct sockaddr __user *, int);
asmlinkage long sys_listen(int, int);
asmlinkage long sys_accept(int, struct sockaddr __user *, int __user *);
asmlinkage long sys_connect(int, struct sockaddr __user *, int);
asmlinkage long sys_getsockname(int, struct sockaddr __user *, int __user *);
asmlinkage long sys_getpeername(int, struct sockaddr __user *, int __user *);
asmlinkage long sys_sendto(int, void __user *, size_t, unsigned,
    struct sockaddr __user *, int);
asmlinkage long sys_recvfrom(int, void __user *, size_t, unsigned,
    struct sockaddr __user *, int __user *);
asmlinkage long sys_setsockopt(int fd, int level, int optname,
    char __user *optval, int optlen);
asmlinkage long sys_getsockopt(int fd, int level, int optname,
    char __user *optval, int __user *optlen);
asmlinkage long sys_shutdown(int, int);
asmlinkage long sys_sendmsg(int fd, struct user_msghdr __user *msg, unsigned flags);
asmlinkage long sys_recvmsg(int fd, struct user_msghdr __user *msg, unsigned flags);

/* mm/filemap.c */
asmlinkage long sys_readahead(int fd, loff_t offset, size_t count);

/* mm/nommu.c, also with MMU */
asmlinkage long sys_brk(unsigned long brk);
asmlinkage long sys_munmap(unsigned long addr, size_t len);
asmlinkage long sys_mremap(unsigned long addr,
      unsigned long old_len, unsigned long new_len,
      unsigned long flags, unsigned long new_addr);

/* security/keys/keyctl.c */
asmlinkage long sys_add_key(const char __user *_type,
       const char __user *_description,
       const void __user *_payload,
       size_t plen,
       key_serial_t destringid);
asmlinkage long sys_request_key(const char __user *_type,
    const char __user *_description,
    const char __user *_callout_info,
    key_serial_t destringid);
asmlinkage long sys_keyctl(int cmd, unsigned long arg2, unsigned long arg3,
      unsigned long arg4, unsigned long arg5);

/* arch/example/kernel/sys_example.c */
#ifdef CONFIG_CLONE_BACKWARDS
asmlinkage long sys_clone(unsigned long, unsigned long, int __user *, unsigned long,
        int __user *);
#else
#ifdef CONFIG_CLONE_BACKWARDS3
asmlinkage long sys_clone(unsigned long, unsigned long, int, int __user *,
     int __user *, unsigned long);
#else
asmlinkage long sys_clone(unsigned long, unsigned long, int __user *,
        int __user *, unsigned long);
#endif
#endif

asmlinkage long sys_clone3(struct clone_args __user *uargs, size_t size);

asmlinkage long sys_execve(const char __user *filename,
  const char __user *const __user *argv,
  const char __user *const __user *envp);

/* mm/fadvise.c */
asmlinkage long sys_fadvise64_64(int fd, loff_t offset, loff_t len, int advice);

/* mm/, CONFIG_MMU only */
asmlinkage long sys_swapon(const char __user *specialfile, int swap_flags);
asmlinkage long sys_swapoff(const char __user *specialfile);
asmlinkage long sys_mprotect(unsigned long start, size_t len,
    unsigned long prot);
asmlinkage long sys_msync(unsigned long start, size_t len, int flags);
asmlinkage long sys_mlock(unsigned long start, size_t len);
asmlinkage long sys_munlock(unsigned long start, size_t len);
asmlinkage long sys_mlockall(int flags);
asmlinkage long sys_munlockall(void);
asmlinkage long sys_mincore(unsigned long start, size_t len,
    unsigned char __user * vec);
asmlinkage long sys_madvise(unsigned long start, size_t len, int behavior);
asmlinkage long sys_process_madvise(int pidfd, const struct iovec __user *vec,
   size_t vlen, int behavior, unsigned int flags);
asmlinkage long sys_process_mrelease(int pidfd, unsigned int flags);
asmlinkage long sys_remap_file_pages(unsigned long start, unsigned long size,
   unsigned long prot, unsigned long pgoff,
   unsigned long flags);
asmlinkage long sys_mbind(unsigned long start, unsigned long len,
    unsigned long mode,
    const unsigned long __user *nmask,
    unsigned long maxnode,
    unsigned flags);
asmlinkage long sys_get_mempolicy(int __user *policy,
    unsigned long __user *nmask,
    unsigned long maxnode,
    unsigned long addr, unsigned long flags);
asmlinkage long sys_set_mempolicy(int mode, const unsigned long __user *nmask,
    unsigned long maxnode);
asmlinkage long sys_migrate_pages(pid_t pid, unsigned long maxnode,
    const unsigned long __user *from,
    const unsigned long __user *to);
asmlinkage long sys_move_pages(pid_t pid, unsigned long nr_pages,
    const void __user * __user *pages,
    const int __user *nodes,
    int __user *status,
    int flags);

asmlinkage long sys_rt_tgsigqueueinfo(pid_t tgid, pid_t  pid, int sig,
  siginfo_t __user *uinfo);
asmlinkage long sys_perf_event_open(
  struct perf_event_attr __user *attr_uptr,
  pid_t pid, int cpu, int group_fd, unsigned long flags);
asmlinkage long sys_accept4(int, struct sockaddr __user *, int __user *, int);
asmlinkage long sys_recvmmsg(int fd, struct mmsghdr __user *msg,
        unsigned int vlen, unsigned flags,
        struct __kernel_timespec __user *timeout);
asmlinkage long sys_recvmmsg_time32(int fd, struct mmsghdr __user *msg,
        unsigned int vlen, unsigned flags,
        struct old_timespec32 __user *timeout);

asmlinkage long sys_wait4(pid_t pid, int __user *stat_addr,
    int options, struct rusage __user *ru);
asmlinkage long sys_prlimit64(pid_t pid, unsigned int resource,
    const struct rlimit64 __user *new_rlim,
    struct rlimit64 __user *old_rlim);
asmlinkage long sys_fanotify_init(unsigned int flags, unsigned int event_f_flags);
asmlinkage long sys_fanotify_mark(int fanotify_fd, unsigned int flags,
      u64 mask, int fd,
      const char  __user *pathname);
asmlinkage long sys_name_to_handle_at(int dfd, const char __user *name,
          struct file_handle __user *handle,
          int __user *mnt_id, int flag);
asmlinkage long sys_open_by_handle_at(int mountdirfd,
          struct file_handle __user *handle,
          int flags);
asmlinkage long sys_clock_adjtime(clockid_t which_clock,
    struct __kernel_timex __user *tx);
asmlinkage long sys_clock_adjtime32(clockid_t which_clock,
    struct old_timex32 __user *tx);
asmlinkage long sys_syncfs(int fd);
asmlinkage long sys_setns(int fd, int nstype);
asmlinkage long sys_pidfd_open(pid_t pid, unsigned int flags);
asmlinkage long sys_sendmmsg(int fd, struct mmsghdr __user *msg,
        unsigned int vlen, unsigned flags);
asmlinkage long sys_process_vm_readv(pid_t pid,
         const struct iovec __user *lvec,
         unsigned long liovcnt,
         const struct iovec __user *rvec,
         unsigned long riovcnt,
         unsigned long flags);
asmlinkage long sys_process_vm_writev(pid_t pid,
          const struct iovec __user *lvec,
          unsigned long liovcnt,
          const struct iovec __user *rvec,
          unsigned long riovcnt,
          unsigned long flags);
asmlinkage long sys_kcmp(pid_t pid1, pid_t pid2, int type,
    unsigned long idx1, unsigned long idx2);
asmlinkage long sys_finit_module(int fd, const char __user *uargs, int flags);
asmlinkage long sys_sched_setattr(pid_t pid,
     struct sched_attr __user *attr,
     unsigned int flags);
asmlinkage long sys_sched_getattr(pid_t pid,
     struct sched_attr __user *attr,
     unsigned int size,
     unsigned int flags);
asmlinkage long sys_renameat2(int olddfd, const char __user *oldname,
         int newdfd, const char __user *newname,
         unsigned int flags);
asmlinkage long sys_seccomp(unsigned int op, unsigned int flags,
       void __user *uargs);
asmlinkage long sys_getrandom(char __user *buf, size_t count,
         unsigned int flags);
asmlinkage long sys_memfd_create(const char __user *uname_ptr, unsigned int flags);
asmlinkage long sys_bpf(int cmd, union bpf_attr *attr, unsigned int size);
asmlinkage long sys_execveat(int dfd, const char __user *filename,
   const char __user *const __user *argv,
   const char __user *const __user *envp, int flags);
asmlinkage long sys_userfaultfd(int flags);
asmlinkage long sys_membarrier(int cmd, unsigned int flags, int cpu_id);
asmlinkage long sys_mlock2(unsigned long start, size_t len, int flags);
asmlinkage long sys_copy_file_range(int fd_in, loff_t __user *off_in,
        int fd_out, loff_t __user *off_out,
        size_t len, unsigned int flags);
asmlinkage long sys_preadv2(unsigned long fd, const struct iovec __user *vec,
       unsigned long vlen, unsigned long pos_l, unsigned long pos_h,
       rwf_t flags);
asmlinkage long sys_pwritev2(unsigned long fd, const struct iovec __user *vec,
       unsigned long vlen, unsigned long pos_l, unsigned long pos_h,
       rwf_t flags);
asmlinkage long sys_pkey_mprotect(unsigned long start, size_t len,
      unsigned long prot, int pkey);
asmlinkage long sys_pkey_alloc(unsigned long flags, unsigned long init_val);
asmlinkage long sys_pkey_free(int pkey);
asmlinkage long sys_statx(int dfd, const char __user *path, unsigned flags,
     unsigned mask, struct statx __user *buffer);
asmlinkage long sys_rseq(struct rseq __user *rseq, uint32_t rseq_len,
    int flags, uint32_t sig);
asmlinkage long sys_open_tree(int dfd, const char __user *path, unsigned flags);
asmlinkage long sys_move_mount(int from_dfd, const char __user *from_path,
          int to_dfd, const char __user *to_path,
          unsigned int ms_flags);
asmlinkage long sys_mount_setattr(int dfd, const char __user *path,
      unsigned int flags,
      struct mount_attr __user *uattr, size_t usize);
asmlinkage long sys_fsopen(const char __user *fs_name, unsigned int flags);
asmlinkage long sys_fsconfig(int fs_fd, unsigned int cmd, const char __user *key,
        const void __user *value, int aux);
asmlinkage long sys_fsmount(int fs_fd, unsigned int flags, unsigned int ms_flags);
asmlinkage long sys_fspick(int dfd, const char __user *path, unsigned int flags);
asmlinkage long sys_pidfd_send_signal(int pidfd, int sig,
           siginfo_t __user *info,
           unsigned int flags);
asmlinkage long sys_pidfd_getfd(int pidfd, int fd, unsigned int flags);
asmlinkage long sys_landlock_create_ruleset(const struct landlock_ruleset_attr __user *attr,
  size_t size, __u32 flags);
asmlinkage long sys_landlock_add_rule(int ruleset_fd, enum landlock_rule_type rule_type,
  const void __user *rule_attr, __u32 flags);
asmlinkage long sys_landlock_restrict_self(int ruleset_fd, __u32 flags);
asmlinkage long sys_memfd_secret(unsigned int flags);
asmlinkage long sys_set_mempolicy_home_node(unsigned long start, unsigned long len,
         unsigned long home_node,
         unsigned long flags);
/*
 * Architecture-specific system calls
 */

/* arch/x86/kernel/ioport.c */
asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int on);

/* pciconfig: alpha, arm, arm64, ia64, sparc */
asmlinkage long sys_pciconfig_read(unsigned long bus, unsigned long dfn,
    unsigned long off, unsigned long len,
    void __user *buf);
asmlinkage long sys_pciconfig_write(unsigned long bus, unsigned long dfn,
    unsigned long off, unsigned long len,
    void __user *buf);
asmlinkage long sys_pciconfig_iobase(long which, unsigned long bus, unsigned long devfn);

/* powerpc */
asmlinkage long sys_spu_run(int fd, __u32 __user *unpc,
     __u32 __user *ustatus);
asmlinkage long sys_spu_create(const char __user *name,
  unsigned int flags, umode_t mode, int fd);

/*
 * Deprecated system calls which are still defined in
 * include/uapi/asm-generic/unistd.h and wanted by >= 1 arch
 */

/* __ARCH_WANT_SYSCALL_NO_AT */
asmlinkage long sys_open(const char __user *filename,
    int flags, umode_t mode);
asmlinkage long sys_link(const char __user *oldname,
    const char __user *newname);
asmlinkage long sys_unlink(const char __user *pathname);
asmlinkage long sys_mknod(const char __user *filename, umode_t mode,
    unsigned dev);
asmlinkage long sys_chmod(const char __user *filename, umode_t mode);
asmlinkage long sys_chown(const char __user *filename,
    uid_t user, gid_t group);
asmlinkage long sys_mkdir(const char __user *pathname, umode_t mode);
asmlinkage long sys_rmdir(const char __user *pathname);
asmlinkage long sys_lchown(const char __user *filename,
    uid_t user, gid_t group);
asmlinkage long sys_access(const char __user *filename, int mode);
asmlinkage long sys_rename(const char __user *oldname,
    const char __user *newname);
asmlinkage long sys_symlink(const char __user *old, const char __user *new);
#if defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64)
asmlinkage long sys_stat64(const char __user *filename,
    struct stat64 __user *statbuf);
asmlinkage long sys_lstat64(const char __user *filename,
    struct stat64 __user *statbuf);
#endif

/* __ARCH_WANT_SYSCALL_NO_FLAGS */
asmlinkage long sys_pipe(int __user *fildes);
asmlinkage long sys_dup2(unsigned int oldfd, unsigned int newfd);
asmlinkage long sys_epoll_create(int size);
asmlinkage long sys_inotify_init(void);
asmlinkage long sys_eventfd(unsigned int count);
asmlinkage long sys_signalfd(int ufd, sigset_t __user *user_mask, size_t sizemask);

/* __ARCH_WANT_SYSCALL_OFF_T */
asmlinkage long sys_sendfile(int out_fd, int in_fd,
        off_t __user *offset, size_t count);
asmlinkage long sys_newstat(const char __user *filename,
    struct stat __user *statbuf);
asmlinkage long sys_newlstat(const char __user *filename,
    struct stat __user *statbuf);
asmlinkage long sys_fadvise64(int fd, loff_t offset, size_t len, int advice);

/* __ARCH_WANT_SYSCALL_DEPRECATED */
asmlinkage long sys_alarm(unsigned int seconds);
asmlinkage long sys_getpgrp(void);
asmlinkage long sys_pause(void);
asmlinkage long sys_time(__kernel_old_time_t __user *tloc);
asmlinkage long sys_time32(old_time32_t __user *tloc);
#ifdef __ARCH_WANT_SYS_UTIME
asmlinkage long sys_utime(char __user *filename,
    struct utimbuf __user *times);
asmlinkage long sys_utimes(char __user *filename,
    struct __kernel_old_timeval __user *utimes);
asmlinkage long sys_futimesat(int dfd, const char __user *filename,
         struct __kernel_old_timeval __user *utimes);
#endif
asmlinkage long sys_futimesat_time32(unsigned int dfd,
         const char __user *filename,
         struct old_timeval32 __user *t);
asmlinkage long sys_utime32(const char __user *filename,
     struct old_utimbuf32 __user *t);
asmlinkage long sys_utimes_time32(const char __user *filename,
      struct old_timeval32 __user *t);
asmlinkage long sys_creat(const char __user *pathname, umode_t mode);
asmlinkage long sys_getdents(unsigned int fd,
    struct linux_dirent __user *dirent,
    unsigned int count);
asmlinkage long sys_select(int n, fd_set __user *inp, fd_set __user *outp,
   fd_set __user *exp, struct __kernel_old_timeval __user *tvp);
asmlinkage long sys_poll(struct pollfd __user *ufds, unsigned int nfds,
    int timeout);
asmlinkage long sys_epoll_wait(int epfd, struct epoll_event __user *events,
    int maxevents, int timeout);
asmlinkage long sys_ustat(unsigned dev, struct ustat __user *ubuf);
asmlinkage long sys_vfork(void);
asmlinkage long sys_recv(int, void __user *, size_t, unsigned);
asmlinkage long sys_send(int, void __user *, size_t, unsigned);
asmlinkage long sys_oldumount(char __user *name);
asmlinkage long sys_uselib(const char __user *library);
asmlinkage long sys_sysfs(int option,
    unsigned long arg1, unsigned long arg2);
asmlinkage long sys_fork(void);

/* obsolete: kernel/time/time.c */
asmlinkage long sys_stime(__kernel_old_time_t __user *tptr);
asmlinkage long sys_stime32(old_time32_t __user *tptr);

/* obsolete: kernel/signal.c */
asmlinkage long sys_sigpending(old_sigset_t __user *uset);
asmlinkage long sys_sigprocmask(int how, old_sigset_t __user *set,
    old_sigset_t __user *oset);
#ifdef CONFIG_OLD_SIGSUSPEND
asmlinkage long sys_sigsuspend(old_sigset_t mask);
#endif

#ifdef CONFIG_OLD_SIGSUSPEND3
asmlinkage long sys_sigsuspend(int unused1, int unused2, old_sigset_t mask);
#endif

#ifdef CONFIG_OLD_SIGACTION
asmlinkage long sys_sigaction(int, const struct old_sigaction __user *,
    struct old_sigaction __user *);
#endif
asmlinkage long sys_sgetmask(void);
asmlinkage long sys_ssetmask(int newmask);
asmlinkage long sys_signal(int sig, __sighandler_t handler);

/* obsolete: kernel/sched/core.c */
asmlinkage long sys_nice(int increment);

/* obsolete: kernel/kexec_file.c */
asmlinkage long sys_kexec_file_load(int kernel_fd, int initrd_fd,
        unsigned long cmdline_len,
        const char __user *cmdline_ptr,
        unsigned long flags);

/* obsolete: kernel/exit.c */
asmlinkage long sys_waitpid(pid_t pid, int __user *stat_addr, int options);

/* obsolete: kernel/uid16.c */
#ifdef CONFIG_HAVE_UID16
asmlinkage long sys_chown16(const char __user *filename,
    old_uid_t user, old_gid_t group);
asmlinkage long sys_lchown16(const char __user *filename,
    old_uid_t user, old_gid_t group);
asmlinkage long sys_fchown16(unsigned int fd, old_uid_t user, old_gid_t group);
asmlinkage long sys_setregid16(old_gid_t rgid, old_gid_t egid);
asmlinkage long sys_setgid16(old_gid_t gid);
asmlinkage long sys_setreuid16(old_uid_t ruid, old_uid_t euid);
asmlinkage long sys_setuid16(old_uid_t uid);
asmlinkage long sys_setresuid16(old_uid_t ruid, old_uid_t euid, old_uid_t suid);
asmlinkage long sys_getresuid16(old_uid_t __user *ruid,
    old_uid_t __user *euid, old_uid_t __user *suid);
asmlinkage long sys_setresgid16(old_gid_t rgid, old_gid_t egid, old_gid_t sgid);
asmlinkage long sys_getresgid16(old_gid_t __user *rgid,
    old_gid_t __user *egid, old_gid_t __user *sgid);
asmlinkage long sys_setfsuid16(old_uid_t uid);
asmlinkage long sys_setfsgid16(old_gid_t gid);
asmlinkage long sys_getgroups16(int gidsetsize, old_gid_t __user *grouplist);
asmlinkage long sys_setgroups16(int gidsetsize, old_gid_t __user *grouplist);
asmlinkage long sys_getuid16(void);
asmlinkage long sys_geteuid16(void);
asmlinkage long sys_getgid16(void);
asmlinkage long sys_getegid16(void);
#endif

/* obsolete: net/socket.c */
asmlinkage long sys_socketcall(int call, unsigned long __user *args);

/* obsolete: fs/stat.c */
asmlinkage long sys_stat(const char __user *filename,
   struct __old_kernel_stat __user *statbuf);
asmlinkage long sys_lstat(const char __user *filename,
   struct __old_kernel_stat __user *statbuf);
asmlinkage long sys_fstat(unsigned int fd,
   struct __old_kernel_stat __user *statbuf);
asmlinkage long sys_readlink(const char __user *path,
    char __user *buf, int bufsiz);

/* obsolete: fs/select.c */
asmlinkage long sys_old_select(struct sel_arg_struct __user *arg);

/* obsolete: fs/readdir.c */
asmlinkage long sys_old_readdir(unsigned int, struct old_linux_dirent __user *, unsigned int);

/* obsolete: kernel/sys.c */
asmlinkage long sys_gethostname(char __user *name, int len);
asmlinkage long sys_uname(struct old_utsname __user *);
asmlinkage long sys_olduname(struct oldold_utsname __user *);
#ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT
asmlinkage long sys_old_getrlimit(unsigned int resource, struct rlimit __user *rlim);
#endif

/* obsolete: ipc */
asmlinkage long sys_ipc(unsigned int call, int first, unsigned long second,
  unsigned long third, void __user *ptr, long fifth);

/* obsolete: mm/ */
asmlinkage long sys_mmap_pgoff(unsigned long addr, unsigned long len,
   unsigned long prot, unsigned long flags,
   unsigned long fd, unsigned long pgoff);
asmlinkage long sys_old_mmap(struct mmap_arg_struct __user *arg);

/*
 * Not a real system call, but a placeholder for syscalls which are
 * not implemented -- see kernel/sys_ni.c
 */
asmlinkage long sys_ni_syscall(void);

#endif /* CONFIG_ARCH_HAS_SYSCALL_WRAPPER */
copy

Posted by piyush23424 on Tue, 01 Nov 2022 12:25:54 +0300