KIRQL NTAPI KeGetCurrentIrql (VOID)
/*
* PURPOSE: Returns the current irq level
* RETURNS: The current irq level
*/
{
KIRQL irql;
ULONG Flags;
Flags = __readeflags();
_disable();
irql = __readfsbyte(FIELD_OFFSET(KPCR, Irql));
if (irql > HIGH_LEVEL)
{
DPRINT1 ("CurrentIrql %x\n", irql);
ASSERT(FALSE);
}
if (Flags & EFLAGS_INTERRUPT_MASK)
{
_enable();
}
return irql;
}
//FUNC_ATTRIBUTE (noinline)
VOID
MemUDummyCLRead (
IN UINT32 Address
)
{
_mm_sfence ();
__readfsbyte (Address);
}
VOID
HalpLowerIrql(KIRQL NewIrql, BOOLEAN FromHalEndSystemInterrupt)
{
ULONG Flags;
UCHAR DpcRequested;
if (NewIrql >= DISPATCH_LEVEL)
{
KeSetCurrentIrql (NewIrql);
APICWrite(APIC_TPR, IRQL2TPR (NewIrql) & APIC_TPR_PRI);
return;
}
Flags = __readeflags();
if (KeGetCurrentIrql() > APC_LEVEL)
{
KeSetCurrentIrql (DISPATCH_LEVEL);
APICWrite(APIC_TPR, IRQL2TPR (DISPATCH_LEVEL) & APIC_TPR_PRI);
DpcRequested = __readfsbyte(FIELD_OFFSET(KIPCR, HalReserved[HAL_DPC_REQUEST]));
if (FromHalEndSystemInterrupt || DpcRequested)
{
__writefsbyte(FIELD_OFFSET(KIPCR, HalReserved[HAL_DPC_REQUEST]), 0);
_enable();
KiDispatchInterrupt();
if (!(Flags & EFLAGS_INTERRUPT_MASK))
{
_disable();
}
}
KeSetCurrentIrql (APC_LEVEL);
}
if (NewIrql == APC_LEVEL)
{
return;
}
if (KeGetCurrentThread () != NULL &&
KeGetCurrentThread ()->ApcState.KernelApcPending)
{
_enable();
KiDeliverApc(KernelMode, NULL, NULL);
if (!(Flags & EFLAGS_INTERRUPT_MASK))
{
_disable();
}
}
KeSetCurrentIrql (PASSIVE_LEVEL);
}
FORCEINLINE
KIRQL
ApicGetCurrentIrql(VOID)
{
#ifdef _M_AMD64
return (KIRQL)__readcr8();
#elif defined(APIC_LAZY_IRQL)
// HACK: some magic to Sync VBox's APIC registers
ApicRead(APIC_VER);
/* Return the field in the PCR */
return (KIRQL)__readfsbyte(FIELD_OFFSET(KPCR, Irql));
#else
// HACK: some magic to Sync VBox's APIC registers
ApicRead(APIC_VER);
/* Read the TPR and convert it to an IRQL */
return TprToIrql(ApicRead(APIC_TPR));
#endif
}