serenity/Kernel/Syscalls/clock.cpp
Idan Horowitz d40038a04f Kernel: Disable big process lock for sys$gettimeofday
This syscall doesn't touch any intra-process shared resources and only
accesses the time via the atomic TimeManagement::now so there's no need
to hold the big lock.
2021-08-06 23:36:12 +02:00

130 lines
3.5 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Time.h>
#include <Kernel/Process.h>
#include <Kernel/Time/TimeManagement.h>
namespace Kernel {
KResultOr<FlatPtr> Process::sys$clock_gettime(clockid_t clock_id, Userspace<timespec*> user_ts)
{
VERIFY_NO_PROCESS_BIG_LOCK(this);
REQUIRE_PROMISE(stdio);
if (!TimeManagement::is_valid_clock_id(clock_id))
return EINVAL;
auto ts = TimeManagement::the().current_time(clock_id).to_timespec();
if (!copy_to_user(user_ts, &ts))
return EFAULT;
return 0;
}
KResultOr<FlatPtr> Process::sys$clock_settime(clockid_t clock_id, Userspace<const timespec*> user_ts)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this);
REQUIRE_PROMISE(settime);
if (!is_superuser())
return EPERM;
auto ts = copy_time_from_user(user_ts);
if (!ts.has_value())
return EFAULT;
switch (clock_id) {
case CLOCK_REALTIME:
TimeManagement::the().set_epoch_time(ts.value());
break;
default:
return EINVAL;
}
return 0;
}
KResultOr<FlatPtr> Process::sys$clock_nanosleep(Userspace<const Syscall::SC_clock_nanosleep_params*> user_params)
{
VERIFY_NO_PROCESS_BIG_LOCK(this);
REQUIRE_PROMISE(stdio);
Syscall::SC_clock_nanosleep_params params;
if (!copy_from_user(&params, user_params))
return EFAULT;
Optional<Time> requested_sleep = copy_time_from_user(params.requested_sleep);
if (!requested_sleep.has_value())
return EFAULT;
bool is_absolute;
switch (params.flags) {
case 0:
is_absolute = false;
break;
case TIMER_ABSTIME:
is_absolute = true;
break;
default:
return EINVAL;
}
if (!TimeManagement::is_valid_clock_id(params.clock_id))
return EINVAL;
bool was_interrupted;
if (is_absolute) {
was_interrupted = Thread::current()->sleep_until(params.clock_id, requested_sleep.value()).was_interrupted();
} else {
Time remaining_sleep;
was_interrupted = Thread::current()->sleep(params.clock_id, requested_sleep.value(), &remaining_sleep).was_interrupted();
timespec remaining_sleep_ts = remaining_sleep.to_timespec();
if (was_interrupted && params.remaining_sleep && !copy_to_user(params.remaining_sleep, &remaining_sleep_ts))
return EFAULT;
}
if (was_interrupted)
return EINTR;
return 0;
}
KResultOr<FlatPtr> Process::sys$adjtime(Userspace<const timeval*> user_delta, Userspace<timeval*> user_old_delta)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this);
if (user_old_delta) {
timespec old_delta_ts = TimeManagement::the().remaining_epoch_time_adjustment();
timeval old_delta;
timespec_to_timeval(old_delta_ts, old_delta);
if (!copy_to_user(user_old_delta, &old_delta))
return EFAULT;
}
if (user_delta) {
REQUIRE_PROMISE(settime);
if (!is_superuser())
return EPERM;
auto delta = copy_time_from_user(user_delta);
if (!delta.has_value())
return EFAULT;
// FIXME: Should use AK::Time internally
TimeManagement::the().set_remaining_epoch_time_adjustment(delta->to_timespec());
}
return 0;
}
KResultOr<FlatPtr> Process::sys$gettimeofday(Userspace<timeval*> user_tv)
{
VERIFY_NO_PROCESS_BIG_LOCK(this);
REQUIRE_PROMISE(stdio);
auto tv = kgettimeofday().to_timeval();
if (!copy_to_user(user_tv, &tv))
return EFAULT;
return 0;
}
}