VOID
KeSetSystemTime (
IN PLARGE_INTEGER NewTime,
OUT PLARGE_INTEGER OldTime,
IN BOOLEAN AdjustInterruptTime,
IN PLARGE_INTEGER HalTimeToSet OPTIONAL
)
/*++
Routine Description:
This function sets the system time to the specified value and updates
timer queue entries to reflect the difference between the old system
time and the new system time.
Arguments:
NewTime - Supplies a pointer to a variable that specifies the new system
time.
OldTime - Supplies a pointer to a variable that will receive the previous
system time.
AdjustInterruptTime - If TRUE the amount of time being adjusted is
also applied to InterruptTime and TickCount.
HalTimeToSet - Supplies an optional time that if specified is to be used
to set the time in the realtime clock.
Return Value:
None.
--*/
{
LIST_ENTRY AbsoluteListHead;
LIST_ENTRY ExpiredListHead;
ULONG Hand;
ULONG Index;
PLIST_ENTRY ListHead;
PKSPIN_LOCK_QUEUE LockQueue;
PLIST_ENTRY NextEntry;
KIRQL OldIrql1;
KIRQL OldIrql2;
LARGE_INTEGER TimeDelta;
TIME_FIELDS TimeFields;
PKTIMER Timer;
ASSERT((NewTime->HighPart & 0xf0000000) == 0);
ASSERT(KeGetCurrentIrql() < DISPATCH_LEVEL);
//
// If a realtime clock value is specified, then convert the time value
// to time fields.
//
if (ARGUMENT_PRESENT(HalTimeToSet)) {
RtlTimeToTimeFields(HalTimeToSet, &TimeFields);
}
//
// Set affinity to the processor that keeps the system time, raise IRQL
// to dispatcher level and lock the dispatcher database, then raise IRQL
// to HIGH_LEVEL to synchronize with the clock interrupt routine.
//
KeSetSystemAffinityThread((KAFFINITY)1);
KiLockDispatcherDatabase(&OldIrql1);
KeRaiseIrql(HIGH_LEVEL, &OldIrql2);
//
// Save the previous system time, set the new system time, and set
// the realtime clock, if a time value is specified.
//
KiQuerySystemTime(OldTime);
#if defined(_AMD64_)
SharedUserData->SystemTime.High2Time = NewTime->HighPart;
*((volatile ULONG64 *)&SharedUserData->SystemTime) = NewTime->QuadPart;
#else
SharedUserData->SystemTime.High2Time = NewTime->HighPart;
SharedUserData->SystemTime.LowPart = NewTime->LowPart;
SharedUserData->SystemTime.High1Time = NewTime->HighPart;
#endif
if (ARGUMENT_PRESENT(HalTimeToSet)) {
ExCmosClockIsSane = HalSetRealTimeClock(&TimeFields);
}
//
// Compute the difference between the previous system time and the new
// system time.
//
TimeDelta.QuadPart = NewTime->QuadPart - OldTime->QuadPart;
//
// Update the boot time to reflect the delta. This keeps time based
// on boot time constant
//
KeBootTime.QuadPart = KeBootTime.QuadPart + TimeDelta.QuadPart;
//
// Track the overall bias applied to the boot time.
//
KeBootTimeBias = KeBootTimeBias + TimeDelta.QuadPart;
//
// Lower IRQL to dispatch level and if needed adjust the physical
// system interrupt time.
//
KeLowerIrql(OldIrql2);
if (AdjustInterruptTime != FALSE) {
AdjustInterruptTime = KeAdjustInterruptTime(TimeDelta.QuadPart);
}
//
// If the physical interrupt time of the system was not adjusted, then
// recompute any absolute timers in the system for the new system time.
//
if (AdjustInterruptTime == FALSE) {
//
// Acquire the timer table lock, remove all absolute timers from the
// timer queue so their due time can be recomputed, and release the
// timer table lock.
//
InitializeListHead(&AbsoluteListHead);
for (Index = 0; Index < TIMER_TABLE_SIZE; Index += 1) {
ListHead = &KiTimerTableListHead[Index].Entry;
LockQueue = KiAcquireTimerTableLock(Index);
NextEntry = ListHead->Flink;
while (NextEntry != ListHead) {
Timer = CONTAINING_RECORD(NextEntry, KTIMER, TimerListEntry);
NextEntry = NextEntry->Flink;
if (Timer->Header.Absolute != FALSE) {
KiRemoveEntryTimer(Timer);
InsertTailList(&AbsoluteListHead, &Timer->TimerListEntry);
}
}
KiReleaseTimerTableLock(LockQueue);
}
//
// Recompute the due time and reinsert all absolute timers in the timer
// tree. If a timer has already expired, then insert the timer in the
// expired timer list.
//
InitializeListHead(&ExpiredListHead);
while (AbsoluteListHead.Flink != &AbsoluteListHead) {
Timer = CONTAINING_RECORD(AbsoluteListHead.Flink, KTIMER, TimerListEntry);
RemoveEntryList(&Timer->TimerListEntry);
Timer->DueTime.QuadPart -= TimeDelta.QuadPart;
Hand = KiComputeTimerTableIndex(Timer->DueTime.QuadPart);
Timer->Header.Hand = (UCHAR)Hand;
LockQueue = KiAcquireTimerTableLock(Hand);
if (KiInsertTimerTable(Timer, Hand) == TRUE) {
KiRemoveEntryTimer(Timer);
InsertTailList(&ExpiredListHead, &Timer->TimerListEntry);
}
KiReleaseTimerTableLock(LockQueue);
}
//
// If any of the attempts to reinsert a timer failed, then timers have
// already expired and must be processed.
//
// N.B. The following function returns with the dispatcher database
// unlocked.
//
KiTimerListExpire(&ExpiredListHead, OldIrql1);
} else {
KiUnlockDispatcherDatabase(OldIrql1);
}
//
// Set affinity back to its original value.
//
KeRevertToUserAffinityThread();
return;
}
VOID
NTAPI
KeSetSystemTime(IN PLARGE_INTEGER NewTime,
OUT PLARGE_INTEGER OldTime,
IN BOOLEAN FixInterruptTime,
IN PLARGE_INTEGER HalTime OPTIONAL)
{
TIME_FIELDS TimeFields;
KIRQL OldIrql, OldIrql2;
LARGE_INTEGER DeltaTime;
PLIST_ENTRY ListHead, NextEntry;
PKTIMER Timer;
PKSPIN_LOCK_QUEUE LockQueue;
LIST_ENTRY TempList, TempList2;
ULONG Hand, i;
/* Sanity checks */
ASSERT((NewTime->HighPart & 0xF0000000) == 0);
ASSERT(KeGetCurrentIrql() <= DISPATCH_LEVEL);
/* Check if this is for the HAL */
if (HalTime) RtlTimeToTimeFields(HalTime, &TimeFields);
/* Set affinity to this CPU, lock the dispatcher, and raise IRQL */
KeSetSystemAffinityThread(1);
OldIrql = KiAcquireDispatcherLock();
KeRaiseIrql(HIGH_LEVEL, &OldIrql2);
/* Query the system time now */
KeQuerySystemTime(OldTime);
/* Set the new system time (ordering of these operations is critical) */
SharedUserData->SystemTime.High2Time = NewTime->HighPart;
SharedUserData->SystemTime.LowPart = NewTime->LowPart;
SharedUserData->SystemTime.High1Time = NewTime->HighPart;
/* Check if this was for the HAL and set the RTC time */
if (HalTime) ExCmosClockIsSane = HalSetRealTimeClock(&TimeFields);
/* Calculate the difference between the new and the old time */
DeltaTime.QuadPart = NewTime->QuadPart - OldTime->QuadPart;
/* Update system boot time */
KeBootTime.QuadPart += DeltaTime.QuadPart;
KeBootTimeBias = KeBootTimeBias + DeltaTime.QuadPart;
/* Lower IRQL back */
KeLowerIrql(OldIrql2);
/* Check if we need to adjust interrupt time */
if (FixInterruptTime) ASSERT(FALSE);
/* Setup a temporary list of absolute timers */
InitializeListHead(&TempList);
/* Loop current timers */
for (i = 0; i < TIMER_TABLE_SIZE; i++)
{
/* Loop the entries in this table and lock the timers */
ListHead = &KiTimerTableListHead[i].Entry;
LockQueue = KiAcquireTimerLock(i);
NextEntry = ListHead->Flink;
while (NextEntry != ListHead)
{
/* Get the timer */
Timer = CONTAINING_RECORD(NextEntry, KTIMER, TimerListEntry);
NextEntry = NextEntry->Flink;
/* Is it absolute? */
if (Timer->Header.Absolute)
{
/* Remove it from the timer list */
KiRemoveEntryTimer(Timer);
/* Insert it into our temporary list */
InsertTailList(&TempList, &Timer->TimerListEntry);
}
}
/* Release the lock */
KiReleaseTimerLock(LockQueue);
}
/* Setup a temporary list of expired timers */
InitializeListHead(&TempList2);
/* Loop absolute timers */
while (TempList.Flink != &TempList)
{
/* Get the timer */
Timer = CONTAINING_RECORD(TempList.Flink, KTIMER, TimerListEntry);
RemoveEntryList(&Timer->TimerListEntry);
/* Update the due time and handle */
Timer->DueTime.QuadPart -= DeltaTime.QuadPart;
Hand = KiComputeTimerTableIndex(Timer->DueTime.QuadPart);
Timer->Header.Hand = (UCHAR)Hand;
/* Lock the timer and re-insert it */
LockQueue = KiAcquireTimerLock(Hand);
if (KiInsertTimerTable(Timer, Hand))
{
/* Remove it from the timer list */
KiRemoveEntryTimer(Timer);
/* Insert it into our temporary list */
InsertTailList(&TempList2, &Timer->TimerListEntry);
}
/* Release the lock */
KiReleaseTimerLock(LockQueue);
}
/* Process expired timers. This releases the dispatcher lock. */
KiTimerListExpire(&TempList2, OldIrql);
/* Revert affinity */
KeRevertToUserAffinityThread();
}