linux/kernel/time/posix-stubs.c
Deepa Dinamani 5c4994102f posix-timers: Use get_timespec64() and put_timespec64()
Usage of these apis and their compat versions makes
the syscalls: clock_gettime, clock_settime, clock_getres
and their compat implementations simpler.

This is a preparatory patch to isolate data conversions to
struct timespec64 at userspace boundaries. This helps contain
the changes needed to transition to new y2038 safe types.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-30 04:13:19 -04:00

232 lines
5.2 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>
#include <linux/compat.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)
#define COMPAT_SYS_NI(name) SYSCALL_ALIAS(compat_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 timespec64 new_tp;
if (which_clock != CLOCK_REALTIME)
return -EINVAL;
if (get_timespec64(&new_tp, tp))
return -EFAULT;
return do_sys_settimeofday64(&new_tp, NULL);
}
int do_clock_gettime(clockid_t which_clock, struct timespec64 *tp)
{
switch (which_clock) {
case CLOCK_REALTIME:
ktime_get_real_ts64(tp);
break;
case CLOCK_MONOTONIC:
ktime_get_ts64(tp);
break;
case CLOCK_BOOTTIME:
get_monotonic_boottime64(tp);
break;
default:
return -EINVAL;
}
return 0;
}
SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
struct timespec __user *, tp)
{
int ret;
struct timespec64 kernel_tp;
ret = do_clock_gettime(which_clock, &kernel_tp);
if (ret)
return ret;
if (put_timespec64(&kernel_tp, tp))
return -EFAULT;
return 0;
}
SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock, struct timespec __user *, tp)
{
struct timespec64 rtn_tp = {
.tv_sec = 0,
.tv_nsec = hrtimer_resolution,
};
switch (which_clock) {
case CLOCK_REALTIME:
case CLOCK_MONOTONIC:
case CLOCK_BOOTTIME:
if (put_timespec64(&rtn_tp, 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 timespec64 t64;
struct timespec t;
switch (which_clock) {
case CLOCK_REALTIME:
case CLOCK_MONOTONIC:
case CLOCK_BOOTTIME:
break;
default:
return -EINVAL;
}
if (copy_from_user(&t, rqtp, sizeof (struct timespec)))
return -EFAULT;
t64 = timespec_to_timespec64(t);
if (!timespec64_valid(&t64))
return -EINVAL;
if (flags & TIMER_ABSTIME)
rmtp = NULL;
current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
current->restart_block.nanosleep.rmtp = rmtp;
return hrtimer_nanosleep(&t64, flags & TIMER_ABSTIME ?
HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
which_clock);
}
#ifdef CONFIG_COMPAT
COMPAT_SYS_NI(timer_create);
COMPAT_SYS_NI(clock_adjtime);
COMPAT_SYS_NI(timer_settime);
COMPAT_SYS_NI(timer_gettime);
COMPAT_SYS_NI(getitimer);
COMPAT_SYS_NI(setitimer);
COMPAT_SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
struct compat_timespec __user *, tp)
{
struct timespec64 new_tp;
if (which_clock != CLOCK_REALTIME)
return -EINVAL;
if (compat_get_timespec64(&new_tp, tp))
return -EFAULT;
return do_sys_settimeofday64(&new_tp, NULL);
}
COMPAT_SYSCALL_DEFINE2(clock_gettime, clockid_t, which_clock,
struct compat_timespec __user *, tp)
{
int ret;
struct timespec64 kernel_tp;
ret = do_clock_gettime(which_clock, &kernel_tp);
if (ret)
return ret;
if (compat_put_timespec64(&kernel_tp, tp))
return -EFAULT;
return 0;
}
COMPAT_SYSCALL_DEFINE2(clock_getres, clockid_t, which_clock,
struct compat_timespec __user *, tp)
{
struct timespec64 rtn_tp = {
.tv_sec = 0,
.tv_nsec = hrtimer_resolution,
};
switch (which_clock) {
case CLOCK_REALTIME:
case CLOCK_MONOTONIC:
case CLOCK_BOOTTIME:
if (compat_put_timespec64(&rtn_tp, tp))
return -EFAULT;
return 0;
default:
return -EINVAL;
}
}
COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags,
struct compat_timespec __user *, rqtp,
struct compat_timespec __user *, rmtp)
{
struct timespec64 t64;
struct timespec t;
switch (which_clock) {
case CLOCK_REALTIME:
case CLOCK_MONOTONIC:
case CLOCK_BOOTTIME:
break;
default:
return -EINVAL;
}
if (compat_get_timespec(&t, rqtp))
return -EFAULT;
t64 = timespec_to_timespec64(t);
if (!timespec64_valid(&t64))
return -EINVAL;
if (flags & TIMER_ABSTIME)
rmtp = NULL;
current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
current->restart_block.nanosleep.compat_rmtp = rmtp;
return hrtimer_nanosleep(&t64, flags & TIMER_ABSTIME ?
HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
which_clock);
}
#endif