reactos/ntoskrnl/ke/i386/thrdini.c
2021-03-24 11:09:20 +01:00

518 lines
15 KiB
C

/*
* COPYRIGHT: See COPYING in the top level directory
* PROJECT: ReactOS kernel
* FILE: ntoskrnl/ke/i386/thrdini.c
* PURPOSE: i386 Thread Context Creation
* PROGRAMMER: Alex Ionescu (alex@relsoft.net)
*/
/* INCLUDES ******************************************************************/
#include <ntoskrnl.h>
#define NDEBUG
#include <debug.h>
typedef struct _KSWITCHFRAME
{
PVOID ExceptionList;
BOOLEAN ApcBypassDisable;
PVOID RetAddr;
} KSWITCHFRAME, *PKSWITCHFRAME;
typedef struct _KSTART_FRAME
{
PKSYSTEM_ROUTINE SystemRoutine;
PKSTART_ROUTINE StartRoutine;
PVOID StartContext;
BOOLEAN UserThread;
} KSTART_FRAME, *PKSTART_FRAME;
typedef struct _KUINIT_FRAME
{
KSWITCHFRAME CtxSwitchFrame;
KSTART_FRAME StartFrame;
KTRAP_FRAME TrapFrame;
FX_SAVE_AREA FxSaveArea;
} KUINIT_FRAME, *PKUINIT_FRAME;
typedef struct _KKINIT_FRAME
{
KSWITCHFRAME CtxSwitchFrame;
KSTART_FRAME StartFrame;
FX_SAVE_AREA FxSaveArea;
} KKINIT_FRAME, *PKKINIT_FRAME;
VOID
FASTCALL
KiSwitchThreads(
IN PKTHREAD OldThread,
IN PKTHREAD NewThread
);
VOID
FASTCALL
KiRetireDpcListInDpcStack(
IN PKPRCB Prcb,
IN PVOID DpcStack
);
/* FUNCTIONS *****************************************************************/
VOID
NTAPI
KiThreadStartup(VOID)
{
PKTRAP_FRAME TrapFrame;
PKSTART_FRAME StartFrame;
PKUINIT_FRAME InitFrame;
/* Get the start and trap frames */
InitFrame = KeGetCurrentThread()->KernelStack;
StartFrame = &InitFrame->StartFrame;
TrapFrame = &InitFrame->TrapFrame;
/* Lower to APC level */
KfLowerIrql(APC_LEVEL);
/* Call the system routine */
StartFrame->SystemRoutine(StartFrame->StartRoutine, StartFrame->StartContext);
/* If we returned, we better be a user thread */
if (!StartFrame->UserThread)
{
KeBugCheck(NO_USER_MODE_CONTEXT);
}
/* Exit to user-mode */
KiServiceExit2(TrapFrame);
}
VOID
NTAPI
KiInitializeContextThread(IN PKTHREAD Thread,
IN PKSYSTEM_ROUTINE SystemRoutine,
IN PKSTART_ROUTINE StartRoutine,
IN PVOID StartContext,
IN PCONTEXT ContextPointer)
{
PFX_SAVE_AREA FxSaveArea;
PFXSAVE_FORMAT FxSaveFormat;
PKSTART_FRAME StartFrame;
PKSWITCHFRAME CtxSwitchFrame;
PKTRAP_FRAME TrapFrame;
CONTEXT LocalContext;
PCONTEXT Context = NULL;
ULONG ContextFlags;
/* Check if this is a With-Context Thread */
if (ContextPointer)
{
/* Set up the Initial Frame */
PKUINIT_FRAME InitFrame;
InitFrame = (PKUINIT_FRAME)((ULONG_PTR)Thread->InitialStack -
sizeof(KUINIT_FRAME));
/* Copy over the context we got */
RtlCopyMemory(&LocalContext, ContextPointer, sizeof(CONTEXT));
Context = &LocalContext;
ContextFlags = CONTEXT_CONTROL;
/* Zero out the trap frame and save area */
RtlZeroMemory(&InitFrame->TrapFrame,
KTRAP_FRAME_LENGTH + sizeof(FX_SAVE_AREA));
/* Setup the Fx Area */
FxSaveArea = &InitFrame->FxSaveArea;
/* Check if we support FXsr */
if (KeI386FxsrPresent)
{
/* Get the FX Save Format Area */
FxSaveFormat = (PFXSAVE_FORMAT)Context->ExtendedRegisters;
/* Set an initial state */
FxSaveFormat->ControlWord = 0x27F;
FxSaveFormat->StatusWord = 0;
FxSaveFormat->TagWord = 0;
FxSaveFormat->ErrorOffset = 0;
FxSaveFormat->ErrorSelector = 0;
FxSaveFormat->DataOffset = 0;
FxSaveFormat->DataSelector = 0;
FxSaveFormat->MXCsr = 0x1F80;
}
else
{
/* Setup the regular save area */
Context->FloatSave.ControlWord = 0x27F;
Context->FloatSave.StatusWord = 0;
Context->FloatSave.TagWord = -1;
Context->FloatSave.ErrorOffset = 0;
Context->FloatSave.ErrorSelector = 0;
Context->FloatSave.DataOffset =0;
Context->FloatSave.DataSelector = 0;
}
/* Check if the CPU has NPX */
if (KeI386NpxPresent)
{
/* Set an intial NPX State */
Context->FloatSave.Cr0NpxState = 0;
FxSaveArea->Cr0NpxState = 0;
FxSaveArea->NpxSavedCpu = 0;
/* Now set the context flags depending on XMM support */
ContextFlags |= (KeI386FxsrPresent) ? CONTEXT_EXTENDED_REGISTERS :
CONTEXT_FLOATING_POINT;
/* Set the Thread's NPX State */
Thread->NpxState = NPX_STATE_NOT_LOADED;
Thread->Header.NpxIrql = PASSIVE_LEVEL;
}
else
{
/* We'll use emulation */
FxSaveArea->Cr0NpxState = CR0_EM;
Thread->NpxState = NPX_STATE_NOT_LOADED &~ CR0_MP;
}
/* Disable any debug registers */
Context->ContextFlags &= ~CONTEXT_DEBUG_REGISTERS;
/* Setup the Trap Frame */
TrapFrame = &InitFrame->TrapFrame;
/* Set up a trap frame from the context. */
KeContextToTrapFrame(Context,
NULL,
TrapFrame,
Context->ContextFlags | ContextFlags,
UserMode);
/* Set SS, DS, ES's RPL Mask properly */
TrapFrame->HardwareSegSs |= RPL_MASK;
TrapFrame->SegDs |= RPL_MASK;
TrapFrame->SegEs |= RPL_MASK;
TrapFrame->Dr7 = 0;
/* Set the debug mark */
TrapFrame->DbgArgMark = 0xBADB0D00;
/* Set the previous mode as user */
TrapFrame->PreviousPreviousMode = UserMode;
/* Terminate the Exception Handler List */
TrapFrame->ExceptionList = EXCEPTION_CHAIN_END;
/* Setup the Stack for KiThreadStartup and Context Switching */
StartFrame = &InitFrame->StartFrame;
CtxSwitchFrame = &InitFrame->CtxSwitchFrame;
/* Tell the thread it will run in User Mode */
Thread->PreviousMode = UserMode;
/* Tell KiThreadStartup of that too */
StartFrame->UserThread = TRUE;
}
else
{
/* Set up the Initial Frame for the system thread */
PKKINIT_FRAME InitFrame;
InitFrame = (PKKINIT_FRAME)((ULONG_PTR)Thread->InitialStack -
sizeof(KKINIT_FRAME));
/* Setup the Fx Area */
FxSaveArea = &InitFrame->FxSaveArea;
RtlZeroMemory(FxSaveArea, sizeof(FX_SAVE_AREA));
/* Check if we have Fxsr support */
if (KeI386FxsrPresent)
{
/* Set the stub FX area */
FxSaveArea->U.FxArea.ControlWord = 0x27F;
FxSaveArea->U.FxArea.MXCsr = 0x1F80;
}
else
{
/* Set the stub FN area */
FxSaveArea->U.FnArea.ControlWord = 0x27F;
FxSaveArea->U.FnArea.TagWord = -1;
}
/* No NPX State */
Thread->NpxState = NPX_STATE_NOT_LOADED;
/* Setup the Stack for KiThreadStartup and Context Switching */
StartFrame = &InitFrame->StartFrame;
CtxSwitchFrame = &InitFrame->CtxSwitchFrame;
/* Tell the thread it will run in Kernel Mode */
Thread->PreviousMode = KernelMode;
/* Tell KiThreadStartup of that too */
StartFrame->UserThread = FALSE;
}
/* Now setup the remaining data for KiThreadStartup */
StartFrame->StartContext = StartContext;
StartFrame->StartRoutine = StartRoutine;
StartFrame->SystemRoutine = SystemRoutine;
/* And set up the Context Switch Frame */
CtxSwitchFrame->RetAddr = KiThreadStartup;
CtxSwitchFrame->ApcBypassDisable = TRUE;
CtxSwitchFrame->ExceptionList = EXCEPTION_CHAIN_END;
/* Save back the new value of the kernel stack. */
Thread->KernelStack = (PVOID)CtxSwitchFrame;
}
DECLSPEC_NORETURN
VOID
KiIdleLoop(VOID)
{
PKPRCB Prcb = KeGetCurrentPrcb();
PKTHREAD OldThread, NewThread;
/* Now loop forever */
while (TRUE)
{
/* Start of the idle loop: disable interrupts */
_enable();
YieldProcessor();
YieldProcessor();
_disable();
/* Check for pending timers, pending DPCs, or pending ready threads */
if ((Prcb->DpcData[0].DpcQueueDepth) ||
(Prcb->TimerRequest) ||
(Prcb->DeferredReadyListHead.Next))
{
/* Quiesce the DPC software interrupt */
HalClearSoftwareInterrupt(DISPATCH_LEVEL);
/* Handle it */
KiRetireDpcList(Prcb);
}
/* Check if a new thread is scheduled for execution */
if (Prcb->NextThread)
{
/* Enable interrupts */
_enable();
/* Capture current thread data */
OldThread = Prcb->CurrentThread;
NewThread = Prcb->NextThread;
/* Set new thread data */
Prcb->NextThread = NULL;
Prcb->CurrentThread = NewThread;
/* The thread is now running */
NewThread->State = Running;
/* Switch away from the idle thread */
KiSwapContext(APC_LEVEL, OldThread);
}
else
{
/* Continue staying idle. Note the HAL returns with interrupts on */
Prcb->PowerState.IdleFunction(&Prcb->PowerState);
}
}
}
BOOLEAN
FASTCALL
KiSwapContextExit(IN PKTHREAD OldThread,
IN PKSWITCHFRAME SwitchFrame)
{
PKIPCR Pcr = (PKIPCR)KeGetPcr();
PKPROCESS OldProcess, NewProcess;
PKTHREAD NewThread;
/* We are on the new thread stack now */
NewThread = Pcr->PrcbData.CurrentThread;
/* Now we are the new thread. Check if it's in a new process */
OldProcess = OldThread->ApcState.Process;
NewProcess = NewThread->ApcState.Process;
if (OldProcess != NewProcess)
{
/* Check if there is a different LDT */
if (*(PULONGLONG)&OldProcess->LdtDescriptor != *(PULONGLONG)&NewProcess->LdtDescriptor)
{
if (NewProcess->LdtDescriptor.LimitLow)
{
KeSetGdtSelector(KGDT_LDT,
((PULONG)&NewProcess->LdtDescriptor)[0],
((PULONG)&NewProcess->LdtDescriptor)[1]);
Ke386SetLocalDescriptorTable(KGDT_LDT);
}
else
{
Ke386SetLocalDescriptorTable(0);
}
}
/* Switch address space and flush TLB */
__writecr3(NewProcess->DirectoryTableBase[0]);
}
/* Clear GS */
Ke386SetGs(0);
/* Set the TEB */
KiSetTebBase((PKPCR)Pcr, &NewThread->Teb->NtTib);
/* Set new TSS fields */
Pcr->TSS->Esp0 = (ULONG_PTR)NewThread->InitialStack;
if (!((KeGetTrapFrame(NewThread))->EFlags & EFLAGS_V86_MASK))
{
Pcr->TSS->Esp0 -= sizeof(KTRAP_FRAME) - FIELD_OFFSET(KTRAP_FRAME, V86Es);
}
Pcr->TSS->Esp0 -= NPX_FRAME_LENGTH;
Pcr->TSS->IoMapBase = NewProcess->IopmOffset;
/* Increase thread context switches */
NewThread->ContextSwitches++;
/* Load data from switch frame */
Pcr->NtTib.ExceptionList = SwitchFrame->ExceptionList;
/* DPCs shouldn't be active */
if (Pcr->PrcbData.DpcRoutineActive)
{
/* Crash the machine */
KeBugCheckEx(ATTEMPTED_SWITCH_FROM_DPC,
(ULONG_PTR)OldThread,
(ULONG_PTR)NewThread,
(ULONG_PTR)OldThread->InitialStack,
0);
}
/* Kernel APCs may be pending */
if (NewThread->ApcState.KernelApcPending)
{
/* Are APCs enabled? */
if (!NewThread->SpecialApcDisable)
{
/* Request APC delivery */
if (SwitchFrame->ApcBypassDisable)
HalRequestSoftwareInterrupt(APC_LEVEL);
else
return TRUE;
}
}
/* Return stating that no kernel APCs are pending*/
return FALSE;
}
VOID
FASTCALL
KiSwapContextEntry(IN PKSWITCHFRAME SwitchFrame,
IN ULONG_PTR OldThreadAndApcFlag)
{
PKIPCR Pcr = (PKIPCR)KeGetPcr();
PKTHREAD OldThread, NewThread;
ULONG Cr0, NewCr0;
/* Save APC bypass disable */
SwitchFrame->ApcBypassDisable = OldThreadAndApcFlag & 3;
SwitchFrame->ExceptionList = Pcr->NtTib.ExceptionList;
/* Increase context switch count and check if tracing is enabled */
Pcr->ContextSwitches++;
if (Pcr->PerfGlobalGroupMask)
{
/* We don't support this yet on x86 either */
DPRINT1("WMI Tracing not supported\n");
ASSERT(FALSE);
}
/* Get thread pointers */
OldThread = (PKTHREAD)(OldThreadAndApcFlag & ~3);
NewThread = Pcr->PrcbData.CurrentThread;
/* Get the old thread and set its kernel stack */
OldThread->KernelStack = SwitchFrame;
/* ISRs can change FPU state, so disable interrupts while checking */
_disable();
/* Get current and new CR0 and check if they've changed */
Cr0 = __readcr0();
NewCr0 = NewThread->NpxState |
(Cr0 & ~(CR0_MP | CR0_EM | CR0_TS)) |
KiGetThreadNpxArea(NewThread)->Cr0NpxState;
if (Cr0 != NewCr0) __writecr0(NewCr0);
/* Now enable interrupts and do the switch */
_enable();
KiSwitchThreads(OldThread, NewThread->KernelStack);
}
VOID
NTAPI
KiDispatchInterrupt(VOID)
{
PKIPCR Pcr = (PKIPCR)KeGetPcr();
PKPRCB Prcb = &Pcr->PrcbData;
PVOID OldHandler;
PKTHREAD NewThread, OldThread;
/* Disable interrupts */
_disable();
/* Check for pending timers, pending DPCs, or pending ready threads */
if ((Prcb->DpcData[0].DpcQueueDepth) ||
(Prcb->TimerRequest) ||
(Prcb->DeferredReadyListHead.Next))
{
/* Switch to safe execution context */
OldHandler = Pcr->NtTib.ExceptionList;
Pcr->NtTib.ExceptionList = EXCEPTION_CHAIN_END;
/* Retire DPCs while under the DPC stack */
KiRetireDpcListInDpcStack(Prcb, Prcb->DpcStack);
/* Restore context */
Pcr->NtTib.ExceptionList = OldHandler;
}
/* Re-enable interrupts */
_enable();
/* Check for quantum end */
if (Prcb->QuantumEnd)
{
/* Handle quantum end */
Prcb->QuantumEnd = FALSE;
KiQuantumEnd();
}
else if (Prcb->NextThread)
{
/* Capture current thread data */
OldThread = Prcb->CurrentThread;
NewThread = Prcb->NextThread;
/* Set new thread data */
Prcb->NextThread = NULL;
Prcb->CurrentThread = NewThread;
/* The thread is now running */
NewThread->State = Running;
OldThread->WaitReason = WrDispatchInt;
/* Make the old thread ready */
KxQueueReadyThread(OldThread, Prcb);
/* Swap to the new thread */
KiSwapContext(APC_LEVEL, OldThread);
}
}
/* EOF */