/*
* COPYRIGHT: See COPYING in the top level directory
* PROJECT: ReactOS Kernel
* FILE: ntoskrnl/ex/time.c
* PURPOSE: Time and Timezone Management
* PROGRAMMERS: Eric Kohl
* Thomas Weidenmueller
*/
/* INCLUDES *****************************************************************/
#include <ntoskrnl.h>
#define NDEBUG
#include <debug.h>
#define TICKSPERMINUTE 600000000
/* GLOBALS ******************************************************************/
/* Note: Bias[minutes] = UTC - local time */
RTL_TIME_ZONE_INFORMATION ExpTimeZoneInfo;
ULONG ExpLastTimeZoneBias = -1;
LARGE_INTEGER ExpTimeZoneBias;
ULONG ExpAltTimeZoneBias;
ULONG ExpTimeZoneId;
ULONG ExpTickCountMultiplier;
ERESOURCE ExpTimeRefreshLock;
ULONG ExpKernelResolutionCount = 0;
ULONG ExpTimerResolutionCount = 0;
/* FUNCTIONS ****************************************************************/
/*++
* @name ExAcquireTimeRefreshLock
*
* The ExReleaseTimeRefreshLock routine acquires the system-wide lock used
* to synchronize clock interrupt frequency changes.
*
* @param Wait
* If TRUE, the system will block the caller thread waiting for the lock
* to become available. If FALSE, the routine will fail if the lock has
* already been acquired.
*
* @return Boolean value indicating success or failure of the lock acquisition.
*
* @remarks None.
*
*--*/
BOOLEAN
NTAPI
ExAcquireTimeRefreshLock(IN BOOLEAN Wait)
{
/* Block APCs */
KeEnterCriticalRegion();
/* Attempt lock acquisition */
if (!(ExAcquireResourceExclusiveLite(&ExpTimeRefreshLock, Wait)))
{
/* Lock was not acquired, enable APCs and fail */
KeLeaveCriticalRegion();
return FALSE;
}
/* Lock has been acquired */
return TRUE;
}
/*++
* @name ExReleaseTimeRefreshLock
*
* The ExReleaseTimeRefreshLock routine releases the system-wide lock used
* to synchronize clock interrupt frequency changes.
*
* @param None.
*
* @return None.
*
* @remarks None.
*
*--*/
VOID
NTAPI
ExReleaseTimeRefreshLock(VOID)
{
/* Release the lock and re-enable APCs */
ExReleaseResourceLite(&ExpTimeRefreshLock);
KeLeaveCriticalRegion();
}
/*++
* @name ExSetTimerResolution
* @exported
*
* The KiInsertQueueApc routine modifies the frequency at which the system
* clock interrupts.
*
* @param DesiredTime
* Specifies the amount of time that should elapse between each timer
* interrupt, in 100-nanosecond units.
*
* This parameter is ignored if SetResolution is FALSE.
*
* @param SetResolution
* If TRUE, the call is a request to set the clock interrupt frequency to
* the value specified by DesiredTime. If FALSE, the call is a request to
* restore the clock interrupt frequency to the system's default value.
*
* @return New timer resolution, in 100-nanosecond ticks.
*
* @remarks (1) The clock frequency is changed only if the DesiredTime value is
* less than the current setting.
*
* (2) The routine just returns the current setting if the DesiredTime
* value is greater than what is currently set.
*
* (3) If the DesiredTime value is less than the system clock can
* support, the routine uses the smallest resolution the system can
* support, and returns that value.
*
* (4) If multiple drivers have attempted to change the clock interrupt
* frequency, the system will only restore the default frequency
* once ALL drivers have called the routine with SetResolution set
* to FALSE.
*
* NB. This routine synchronizes with IRP_MJ_POWER requests through the
* TimeRefreshLock.
*
*--*/
ULONG
NTAPI
ExSetTimerResolution(IN ULONG DesiredTime,
IN BOOLEAN SetResolution)
{
ULONG CurrentIncrement;
/* Wait for clock interrupt frequency and power requests to synchronize */
ExAcquireTimeRefreshLock(TRUE);
/* Obey remark 2*/
CurrentIncrement = KeTimeIncrement;
/* Check the type of operation this is */
if (SetResolution)
{
/*
* If this is the first kernel change, bump the timer resolution change
* count, then bump the kernel change count as well.
*
* These two variables are tracked differently since user-mode processes
* can also change the timer resolution through the NtSetTimerResolution
* system call. A per-process flag in the EPROCESS then stores the per-
* process change state.
*
*/
if (!ExpKernelResolutionCount++) ExpTimerResolutionCount++;
/* Obey remark 3 */
if (DesiredTime < KeMinimumIncrement) DesiredTime = KeMinimumIncrement;
/* Obey remark 1 */
if (DesiredTime < KeTimeIncrement)
{
/* Force this thread on CPU zero, since we don't want it to drift */
KeSetSystemAffinityThread(1);
/* Now call the platform driver (HAL) to make the change */
CurrentIncrement = HalSetTimeIncrement(DesiredTime);
/* Put the thread back to its original affinity */
KeRevertToUserAffinityThread();
/* Finally, keep track of the new value in the kernel */
KeTimeIncrement = CurrentIncrement;
}
}
else
{
/* First, make sure that a driver has actually changed the resolution */
if (ExpKernelResolutionCount)
{
/* Obey remark 4 */
if (--ExpKernelResolutionCount)
{
/*
* All kernel drivers have requested the original frequency to
* be restored, but there might still be user processes with an
* ongoing clock interrupt frequency change, so make sure that
* this isn't the case.
*/
if (--ExpTimerResolutionCount)
{
/* Force this thread on one CPU so that it doesn't drift */
KeSetSystemAffinityThread(1);
/* Call the HAL to restore the frequency to its default */
CurrentIncrement = HalSetTimeIncrement(KeMaximumIncrement);
/* Put the thread back to its original affinity */
KeRevertToUserAffinityThread();
/* Finally, keep track of the new value in the kernel */
KeTimeIncrement = CurrentIncrement;
}
}
}
}
/* Release the clock interrupt frequency lock since changes are done */
ExReleaseTimeRefreshLock();
/* And return the current value -- which could reflect the new frequency */
return CurrentIncrement;
}
VOID
NTAPI
ExUpdateSystemTimeFromCmos(IN BOOLEAN UpdateInterruptTime,
IN ULONG MaxSepInSeconds)
{
/* FIXME: TODO */
return;
}
BOOLEAN
NTAPI
ExRefreshTimeZoneInformation(IN PLARGE_INTEGER CurrentBootTime)
{
LARGE_INTEGER CurrentTime;
NTSTATUS Status;
/* Read time zone information from the registry */
Status = RtlQueryTimeZoneInformation(&ExpTimeZoneInfo);
if (!NT_SUCCESS(Status))
{
/* Failed, clear all data */
RtlZeroMemory(&ExpTimeZoneInfo, sizeof(RTL_TIME_ZONE_INFORMATION));
ExpTimeZoneBias.QuadPart = (LONGLONG)0;
ExpTimeZoneId = TIME_ZONE_ID_UNKNOWN;
}
else
{
/* FIXME: Calculate transition dates */
/* Set bias and ID */
ExpTimeZoneBias.QuadPart = ((LONGLONG)(ExpTimeZoneInfo.Bias +
ExpTimeZoneInfo.StandardBias)) *
TICKSPERMINUTE;
ExpTimeZoneId = TIME_ZONE_ID_STANDARD;
}
/* Change it for user-mode applications */
SharedUserData->TimeZoneBias.High1Time = ExpTimeZoneBias.u.HighPart;
SharedUserData->TimeZoneBias.High2Time = ExpTimeZoneBias.u.HighPart;
SharedUserData->TimeZoneBias.LowPart = ExpTimeZoneBias.u.LowPart;
SharedUserData->TimeZoneId = ExpTimeZoneId;
/* Convert boot time from local time to UTC */
KeBootTime.QuadPart += ExpTimeZoneBias.QuadPart;
/* Convert system time from local time to UTC */
do
{
CurrentTime.u.HighPart = SharedUserData->SystemTime.High1Time;
CurrentTime.u.LowPart = SharedUserData->SystemTime.LowPart;
} while (CurrentTime.u.HighPart != SharedUserData->SystemTime.High2Time);
/* Change it for user-mode applications */
CurrentTime.QuadPart += ExpTimeZoneBias.QuadPart;
SharedUserData->SystemTime.LowPart = CurrentTime.u.LowPart;
SharedUserData->SystemTime.High1Time = CurrentTime.u.HighPart;
SharedUserData->SystemTime.High2Time = CurrentTime.u.HighPart;
/* Return success */
return TRUE;
}
NTSTATUS
ExpSetTimeZoneInformation(PRTL_TIME_ZONE_INFORMATION TimeZoneInformation)
{
LARGE_INTEGER LocalTime, SystemTime, OldTime;
TIME_FIELDS TimeFields;
DPRINT("ExpSetTimeZoneInformation() called\n");
DPRINT("Old time zone bias: %d minutes\n", ExpTimeZoneInfo.Bias);
DPRINT("Old time zone standard bias: %d minutes\n",
ExpTimeZoneInfo.StandardBias);
DPRINT("New time zone bias: %d minutes\n", TimeZoneInformation->Bias);
DPRINT("New time zone standard bias: %d minutes\n",
TimeZoneInformation->StandardBias);
/* Get the local time */
HalQueryRealTimeClock(&TimeFields);
RtlTimeFieldsToTime(&TimeFields, &LocalTime);
/* FIXME: Calculate transition dates */
/* Calculate the bias and set the ID */
ExpTimeZoneBias.QuadPart = ((LONGLONG)(TimeZoneInformation->Bias +
TimeZoneInformation->StandardBias)) *
TICKSPERMINUTE;
ExpTimeZoneId = TIME_ZONE_ID_STANDARD;
/* Copy the timezone information */
RtlCopyMemory(&ExpTimeZoneInfo,
TimeZoneInformation,
sizeof(RTL_TIME_ZONE_INFORMATION));
/* Set the new time zone information */
SharedUserData->TimeZoneBias.High1Time = ExpTimeZoneBias.u.HighPart;
SharedUserData->TimeZoneBias.High2Time = ExpTimeZoneBias.u.HighPart;
SharedUserData->TimeZoneBias.LowPart = ExpTimeZoneBias.u.LowPart;
SharedUserData->TimeZoneId = ExpTimeZoneId;
DPRINT("New time zone bias: %I64d minutes\n",
ExpTimeZoneBias.QuadPart / TICKSPERMINUTE);
/* Calculate the new system time */
ExLocalTimeToSystemTime(&LocalTime, &SystemTime);
/* Set the new system time */
KeSetSystemTime(&SystemTime, &OldTime, FALSE, NULL);
/* Return success */
DPRINT("ExpSetTimeZoneInformation() done\n");
return STATUS_SUCCESS;
}
/*
* FUNCTION: Sets the system time.
* PARAMETERS:
* NewTime - Points to a variable that specified the new time
* of day in the standard time format.
* OldTime - Optionally points to a variable that receives the
* old time of day in the standard time format.
* RETURNS: Status
*/
NTSTATUS
NTAPI
NtSetSystemTime(IN PLARGE_INTEGER SystemTime,
OUT PLARGE_INTEGER PreviousTime OPTIONAL)
{
LARGE_INTEGER OldSystemTime;
LARGE_INTEGER NewSystemTime;
LARGE_INTEGER LocalTime;
TIME_FIELDS TimeFields;
KPROCESSOR_MODE PreviousMode = ExGetPreviousMode();
NTSTATUS Status = STATUS_SUCCESS;
PAGED_CODE();
/* Check if we were called from user-mode */
if (PreviousMode != KernelMode)
{
_SEH2_TRY
{
/* Verify the time pointers */
NewSystemTime = ProbeForReadLargeInteger(SystemTime);
if(PreviousTime) ProbeForWriteLargeInteger(PreviousTime);
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
/* Return the exception code */
_SEH2_YIELD(return _SEH2_GetExceptionCode());
}
_SEH2_END;
}
else
{
/* Reuse the pointer */
NewSystemTime = *SystemTime;
}
/* Make sure we have permission to change the time */
if (!SeSinglePrivilegeCheck(SeSystemtimePrivilege, PreviousMode))
{
DPRINT1("NtSetSystemTime: Caller requires the "
"SeSystemtimePrivilege privilege!\n");
return STATUS_PRIVILEGE_NOT_HELD;
}
/* Convert the time and set it in HAL */
ExSystemTimeToLocalTime(&NewSystemTime, &LocalTime);
RtlTimeToTimeFields(&LocalTime, &TimeFields);
HalSetRealTimeClock(&TimeFields);
/* Now set system time */
KeSetSystemTime(&NewSystemTime, &OldSystemTime, FALSE, NULL);
/* Check if caller wanted previous time */
if (PreviousTime)
{
/* Enter SEH Block for return */
_SEH2_TRY
{
/* Return the previous time */
*PreviousTime = OldSystemTime;
}
_SEH2_EXCEPT(ExSystemExceptionFilter())
{
/* Get the exception code */
Status = _SEH2_GetExceptionCode();
}
_SEH2_END;
}
/* Return status */
return Status;
}
/*
* FUNCTION: Retrieves the system time.
* PARAMETERS:
* CurrentTime - Points to a variable that receives the current
* time of day in the standard time format.
*/
NTSTATUS
NTAPI
NtQuerySystemTime(OUT PLARGE_INTEGER SystemTime)
{
KPROCESSOR_MODE PreviousMode = ExGetPreviousMode();
PAGED_CODE();
/* Check if we were called from user-mode */
if (PreviousMode != KernelMode)
{
_SEH2_TRY
{
/* Verify the time pointer */
ProbeForWriteLargeInteger(SystemTime);
/*
* It's safe to pass the pointer directly to KeQuerySystemTime
* as it's just a basic copy to this pointer. If it raises an
* exception nothing dangerous can happen!
*/
KeQuerySystemTime(SystemTime);
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
/* Return the exception code */
_SEH2_YIELD(return _SEH2_GetExceptionCode());
}
_SEH2_END;
}
else
{
/* Query the time directly */
KeQuerySystemTime(SystemTime);
}
/* Return success */
return STATUS_SUCCESS;
}
/*
* @implemented
*/
VOID
NTAPI
ExLocalTimeToSystemTime(PLARGE_INTEGER LocalTime,
PLARGE_INTEGER SystemTime)
{
SystemTime->QuadPart = LocalTime->QuadPart + ExpTimeZoneBias.QuadPart;
}
/*
* @implemented
*/
VOID
NTAPI
ExSystemTimeToLocalTime(PLARGE_INTEGER SystemTime,
PLARGE_INTEGER LocalTime)
{
LocalTime->QuadPart = SystemTime->QuadPart - ExpTimeZoneBias.QuadPart;
}
/*
* @implemented
*/
NTSTATUS
NTAPI
NtQueryTimerResolution(OUT PULONG MinimumResolution,
OUT PULONG MaximumResolution,
OUT PULONG ActualResolution)
{
KPROCESSOR_MODE PreviousMode = ExGetPreviousMode();
/* Check if the call came from user-mode */
if (PreviousMode != KernelMode)
{
_SEH2_TRY
{
/* Probe the parameters */
ProbeForWriteUlong(MinimumResolution);
ProbeForWriteUlong(MaximumResolution);
ProbeForWriteUlong(ActualResolution);
/*
* Set the parameters to the actual values.
*
* NOTE:
* MinimumResolution corresponds to the biggest time increment and
* MaximumResolution corresponds to the smallest time increment.
*/
*MinimumResolution = KeMaximumIncrement;
*MaximumResolution = KeMinimumIncrement;
*ActualResolution = KeTimeIncrement;
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
/* Return the exception code */
_SEH2_YIELD(return _SEH2_GetExceptionCode());
}
_SEH2_END;
}
else
{
/* Set the parameters to the actual values */
*MinimumResolution = KeMaximumIncrement;
*MaximumResolution = KeMinimumIncrement;
*ActualResolution = KeTimeIncrement;
}
/* Return success */
return STATUS_SUCCESS;
}
/*
* @implemented
*/
NTSTATUS
NTAPI
NtSetTimerResolution(IN ULONG DesiredResolution,
IN BOOLEAN SetResolution,
OUT PULONG CurrentResolution)
{
NTSTATUS Status;
KPROCESSOR_MODE PreviousMode = ExGetPreviousMode();
PEPROCESS Process = PsGetCurrentProcess();
ULONG NewResolution;
/* Check if the call came from user-mode */
if (PreviousMode != KernelMode)
{
_SEH2_TRY
{
/* Probe the parameter */
ProbeForWriteUlong(CurrentResolution);
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
/* Return the exception code */
_SEH2_YIELD(return _SEH2_GetExceptionCode());
}
_SEH2_END;
}
/* Set and return the new resolution */
NewResolution = ExSetTimerResolution(DesiredResolution, SetResolution);
if (PreviousMode != KernelMode)
{
_SEH2_TRY
{
*CurrentResolution = NewResolution;
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
/* Return the exception code */
_SEH2_YIELD(return _SEH2_GetExceptionCode());
}
_SEH2_END;
}
else
{
*CurrentResolution = NewResolution;
}
if (SetResolution || Process->SetTimerResolution)
{
/* The resolution has been changed now or in an earlier call */
Status = STATUS_SUCCESS;
}
else
{
/* The resolution hasn't been changed */
Status = STATUS_TIMER_RESOLUTION_NOT_SET;
}
/* Update the flag */
Process->SetTimerResolution = SetResolution;
return Status;
}
/* EOF */