linux/kernel/time/posix-stubs.c

124 lines
3.0 KiB
C

/*
* Dummy stubs used when CONFIG_POSIX_TIMERS=n
*
* Created by: Nicolas Pitre, July 2016
* Copyright: (C) 2016 Linaro Limited
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/syscalls.h>
#include <linux/ktime.h>
#include <linux/timekeeping.h>
#include <linux/posix-timers.h>
asmlinkage long sys_ni_posix_timers(void)
{
pr_err_once("process %d (%s) attempted a POSIX timer syscall "
"while CONFIG_POSIX_TIMERS is not set\n",
current->pid, current->comm);
return -ENOSYS;
}
#define SYS_NI(name) SYSCALL_ALIAS(sys_##name, sys_ni_posix_timers)
SYS_NI(timer_create);
SYS_NI(timer_gettime);
SYS_NI(timer_getoverrun);
SYS_NI(timer_settime);
SYS_NI(timer_delete);
SYS_NI(clock_adjtime);
SYS_NI(getitimer);
SYS_NI(setitimer);
#ifdef __ARCH_WANT_SYS_ALARM
SYS_NI(alarm);
#endif
/*
* We preserve minimal support for CLOCK_REALTIME and CLOCK_MONOTONIC
* as it is easy to remain compatible with little code. CLOCK_BOOTTIME
* is also included for convenience as at least systemd uses it.
*/
SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
const struct timespec __user *, tp)
{
struct timespec new_tp;
if (which_clock != CLOCK_REALTIME)
return -EINVAL;
if (copy_from_user(&new_tp, tp, sizeof (*tp)))
return -EFAULT;
return do_sys_settimeofday(&new_tp, NULL);
}
SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
struct timespec __user *,tp)
{
struct timespec kernel_tp;
switch (which_clock) {
case CLOCK_REALTIME: ktime_get_real_ts(&kernel_tp); break;
case CLOCK_MONOTONIC: ktime_get_ts(&kernel_tp); break;
case CLOCK_BOOTTIME: get_monotonic_boottime(&kernel_tp); break;
default: return -EINVAL;
}
if (copy_to_user(tp, &kernel_tp, sizeof (kernel_tp)))
return -EFAULT;
return 0;
}
SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock, struct timespec __user *, tp)
{
struct timespec rtn_tp = {
.tv_sec = 0,
.tv_nsec = hrtimer_resolution,
};
switch (which_clock) {
case CLOCK_REALTIME:
case CLOCK_MONOTONIC:
case CLOCK_BOOTTIME:
if (copy_to_user(tp, &rtn_tp, sizeof(rtn_tp)))
return -EFAULT;
return 0;
default:
return -EINVAL;
}
}
SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
const struct timespec __user *, rqtp,
struct timespec __user *, rmtp)
{
struct timespec t;
switch (which_clock) {
case CLOCK_REALTIME:
case CLOCK_MONOTONIC:
case CLOCK_BOOTTIME:
if (copy_from_user(&t, rqtp, sizeof (struct timespec)))
return -EFAULT;
if (!timespec_valid(&t))
return -EINVAL;
return hrtimer_nanosleep(&t, rmtp, flags & TIMER_ABSTIME ?
HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
which_clock);
default:
return -EINVAL;
}
}
#ifdef CONFIG_COMPAT
long clock_nanosleep_restart(struct restart_block *restart_block)
{
return hrtimer_nanosleep_restart(restart_block);
}
#endif