/*++
Copyright (c) 1999, 2000 Microsoft Corporation
Module Name:
idle.c
Abstract
Author:
Doron H.
Environment:
Kernel mode only
Revision History:
--*/
#ifdef ALLOC_PRAGMA
#endif
#include "pch.h"
KSPIN_LOCK idleDeviceListSpinLock;
LIST_ENTRY idleDeviceList;
KTIMER idleTimer;
KDPC idleTimerDpc;
LONG numIdleDevices = 0;
#define HID_IDLE_SCAN_INTERVAL 1
typedef struct _HID_IDLE_DEVICE_INFO {
LIST_ENTRY entry;
ULONG idleCount;
ULONG idleTime;
PDEVICE_OBJECT device;
BOOLEAN tryAgain;
} HID_IDLE_DEVICE_INFO, *PHID_IDLE_DEVICE_INFO;
VOID
HidpIdleTimerDpcProc(
IN PKDPC Dpc,
IN PDEVICE_OBJECT DeviceObject,
IN PVOID Context1,
IN PVOID Context2
);
NTSTATUS
HidpRegisterDeviceForIdleDetection(
PDEVICE_OBJECT DeviceObject,
ULONG IdleTime,
PULONG *IdleTimeout
)
{
PHID_IDLE_DEVICE_INFO info = NULL;
KIRQL irql;
PLIST_ENTRY entry = NULL;
static BOOLEAN firstCall = TRUE;
BOOLEAN freeInfo = FALSE;
NTSTATUS status = STATUS_UNSUCCESSFUL;
if (firstCall) {
KeInitializeSpinLock(&idleDeviceListSpinLock);
InitializeListHead(&idleDeviceList);
KeInitializeTimerEx(&idleTimer, NotificationTimer);
KeInitializeDpc(&idleTimerDpc, HidpIdleTimerDpcProc, NULL);
firstCall = FALSE;
}
KeAcquireSpinLock(&idleDeviceListSpinLock, &irql);
if (IdleTime == 0) {
ASSERT(numIdleDevices >= 0);
//
// Remove the device from the list
//
for (entry = idleDeviceList.Flink;
entry != &idleDeviceList;
entry = entry->Flink) {
info = CONTAINING_RECORD(entry, HID_IDLE_DEVICE_INFO, entry);
if (info->device == DeviceObject) {
DBGINFO(("Remove device idle on fdo 0x%x", DeviceObject));
numIdleDevices--;
ObDereferenceObject(DeviceObject);
RemoveEntryList(entry);
status = STATUS_SUCCESS;
ExFreePool(info);
*IdleTimeout = BAD_POINTER;
break;
}
}
if (NT_SUCCESS(status)) {
//
// If there are no more idle devices we can stop the timer
//
if (IsListEmpty(&idleDeviceList)) {
ASSERT(numIdleDevices == 0);
DBGINFO(("Idle detection list empty. Stopping timer."));
KeCancelTimer(&idleTimer);
}
}
} else {
LARGE_INTEGER scanTime;
BOOLEAN empty = FALSE;
DBGINFO(("Register for device idle on fdo 0x%x", DeviceObject));
//
// Check if we've already started this.
//
status = STATUS_SUCCESS;
for (entry = idleDeviceList.Flink;
entry != &idleDeviceList;
entry = entry->Flink) {
info = CONTAINING_RECORD(entry, HID_IDLE_DEVICE_INFO, entry);
if (info->device == DeviceObject) {
DBGWARN(("Device already registered for idle detection. Ignoring."));
ASSERT(*IdleTimeout == &(info->idleCount));
status = STATUS_UNSUCCESSFUL;
}
}
if (NT_SUCCESS(status)) {
info = (PHID_IDLE_DEVICE_INFO)
ALLOCATEPOOL(NonPagedPool, sizeof(HID_IDLE_DEVICE_INFO));
if (info != NULL) {
ObReferenceObject(DeviceObject);
RtlZeroMemory(info, sizeof(HID_IDLE_DEVICE_INFO));
info->device = DeviceObject;
info->idleTime = IdleTime;
if (IsListEmpty(&idleDeviceList)) {
empty = TRUE;
}
InsertTailList(&idleDeviceList, &info->entry);
*IdleTimeout = &(info->idleCount);
numIdleDevices++;
if (empty) {
DBGINFO(("Starting idle detection timer for first time."));
//
// Turn on idle detection
//
scanTime = RtlConvertLongToLargeInteger(-10*1000*1000 * HID_IDLE_SCAN_INTERVAL);
KeSetTimerEx(&idleTimer,
scanTime,
HID_IDLE_SCAN_INTERVAL*1000, // call wants milliseconds
&idleTimerDpc);
}
} else {
status = STATUS_INSUFFICIENT_RESOURCES;
}
}
}
KeReleaseSpinLock(&idleDeviceListSpinLock, irql);
return status;
}
VOID
HidpIdleTimerDpcProc(
IN PKDPC Dpc,
IN PDEVICE_OBJECT DeviceObject,
IN PVOID Context1,
IN PVOID Context2
)
{
PLIST_ENTRY entry;
PHID_IDLE_DEVICE_INFO info;
ULONG oldCount;
KIRQL irql1, irql2;
BOOLEAN ok = FALSE;
PFDO_EXTENSION fdoExt;
LONG idleState;
UNREFERENCED_PARAMETER(Context1);
UNREFERENCED_PARAMETER(Context2);
KeAcquireSpinLock(&idleDeviceListSpinLock, &irql1);
entry = idleDeviceList.Flink;
while (entry != &idleDeviceList) {
info = CONTAINING_RECORD(entry, HID_IDLE_DEVICE_INFO, entry);
fdoExt = &((PHIDCLASS_DEVICE_EXTENSION) info->device->DeviceExtension)->fdoExt;
KeAcquireSpinLock(&fdoExt->idleNotificationSpinLock, &irql2);
oldCount = InterlockedIncrement(&info->idleCount);
if (info->tryAgain || ((oldCount+1) == info->idleTime)) {
PIO_WORKITEM item = IoAllocateWorkItem(info->device);
if (item) {
info->tryAgain = FALSE;
SS_TRAP;
KeResetEvent(&fdoExt->idleDoneEvent);
ASSERT(fdoExt->idleState != IdleIrpSent);
ASSERT(fdoExt->idleState != IdleCallbackReceived);
ASSERT(fdoExt->idleState != IdleComplete);
idleState = InterlockedCompareExchange(&fdoExt->idleState,
IdleIrpSent,
IdleWaiting);
if (fdoExt->idleState == IdleIrpSent) {
ok = TRUE;
} else {
// We shouldn't get here if we're disabled.
ASSERT(idleState != IdleDisabled);
DBGWARN(("Resetting timer to zero for fdo %x in state %x",
info->device,fdoExt->idleState));
info->idleCount = 0;
}
if (ok) {
IoQueueWorkItem(item,
HidpIdleTimeWorker,
DelayedWorkQueue,
item);
} else {
IoFreeWorkItem(item);
}
} else {
info->tryAgain = TRUE;
}
}
KeReleaseSpinLock(&fdoExt->idleNotificationSpinLock, irql2);
entry = entry->Flink;
}
KeReleaseSpinLock(&idleDeviceListSpinLock, irql1);
}
NTSTATUS
HidpIdleNotificationRequestComplete(
PDEVICE_OBJECT DeviceObject,
PIRP Irp,
PHIDCLASS_DEVICE_EXTENSION HidDeviceExtension
)
{
FDO_EXTENSION *fdoExt;
PDO_EXTENSION *pdoExt;
KIRQL irql;
LONG prevIdleState = IdleWaiting;
POWER_STATE powerState;
NTSTATUS status = Irp->IoStatus.Status;
ULONG count, i;
PIRP delayedIrp;
LIST_ENTRY dequeue, *entry;
PIO_STACK_LOCATION stack;
//
// DeviceObject is NULL because we sent the irp
//
UNREFERENCED_PARAMETER(DeviceObject);
fdoExt = &HidDeviceExtension->fdoExt;
DBGVERBOSE(("Idle irp completed status 0x%x for fdo 0x%x",
status, fdoExt->fdo));
//
// Cancel any outstanding WW irp we queued up for the exclusive purpose
// of selective suspend.
//
KeAcquireSpinLock(&fdoExt->collectionWaitWakeIrpQueueSpinLock, &irql);
if (IsListEmpty(&fdoExt->collectionWaitWakeIrpQueue) &&
HidpIsWaitWakePending(fdoExt, FALSE)) {
if (ISPTR(fdoExt->waitWakeIrp)) {
DBGINFO(("Cancelling the WW irp that was queued for idle."))
IoCancelIrp(fdoExt->waitWakeIrp);
} else {
TRAP;
}
}
KeReleaseSpinLock(&fdoExt->collectionWaitWakeIrpQueueSpinLock, irql);
switch (status) {
case STATUS_SUCCESS:
// we successfully idled the device we are either now back in D0,
// or will be very soon.
KeAcquireSpinLock(&fdoExt->idleNotificationSpinLock, &irql);
if (fdoExt->devicePowerState == PowerDeviceD0) {
prevIdleState = InterlockedCompareExchange(&fdoExt->idleState,
IdleWaiting,
IdleComplete);
DBGASSERT(fdoExt->idleState == IdleWaiting,
("IdleCompletion, prev state not IdleWaiting, actually %x",prevIdleState),
TRUE);
if (ISPTR(fdoExt->idleTimeoutValue)) {
InterlockedExchange(fdoExt->idleTimeoutValue, 0);
}
}
KeReleaseSpinLock(&fdoExt->idleNotificationSpinLock, irql);
break;
case STATUS_INVALID_DEVICE_REQUEST:
case STATUS_NOT_SUPPORTED:
// the bus below does not support idle timeouts, forget about it
DBGINFO(("Bus does not support idle. Removing for fdo %x",
fdoExt->fdo));
//
// Call to cancel idle notification.
//
ASSERT(fdoExt->idleState == IdleIrpSent);
ASSERT(fdoExt->devicePowerState == PowerDeviceD0);
fdoExt->idleState = IdleWaiting;
HidpCancelIdleNotification(fdoExt, TRUE);
KeSetEvent(&fdoExt->idleDoneEvent, 0, FALSE);
break;
// we cancelled the request
case STATUS_CANCELLED:
DBGINFO(("Idle Irp completed cancelled"));
// transitioned into a power state where we could not idle out
case STATUS_POWER_STATE_INVALID:
// oops, there was already a request in the bus below us
case STATUS_DEVICE_BUSY:
default:
//
// We must reset ourselves.
//
KeAcquireSpinLock(&fdoExt->idleNotificationSpinLock, &irql);
DBGASSERT((fdoExt->idleState != IdleWaiting),
("Idle completion, previous state was already waiting."),
FALSE);
prevIdleState = fdoExt->idleState;
if (prevIdleState == IdleIrpSent) {
ASSERT(fdoExt->devicePowerState == PowerDeviceD0);
fdoExt->idleCancelling = FALSE;
if (ISPTR(fdoExt->idleTimeoutValue) &&
prevIdleState != IdleComplete) {
InterlockedExchange(fdoExt->idleTimeoutValue, 0);
}
InterlockedExchange(&fdoExt->idleState, IdleWaiting);
}
KeReleaseSpinLock(&fdoExt->idleNotificationSpinLock, irql);
if (prevIdleState == IdleComplete) {
//
// We now have to power up the stack.
//
DBGINFO(("Fully idled. Must power up stack."))
powerState.DeviceState = PowerDeviceD0;
PoRequestPowerIrp(((PHIDCLASS_DEVICE_EXTENSION) fdoExt->fdo->DeviceExtension)->hidExt.PhysicalDeviceObject,
IRP_MN_SET_POWER,
powerState,
HidpDelayedPowerPoRequestComplete,
fdoExt,
NULL);
} else if (prevIdleState == IdleIrpSent) {
//
// Dequeue any enqueued irps and send them on their way.
// This is for the case where we didn't make it to suspend, but
// enqueued irps anyways. I.e. using mouse, set caps lock on
// ps/2 keybd causing write to be sent to usb kbd.
//
if (fdoExt->devicePowerState == PowerDeviceD0) {
for (i = 0; i < fdoExt->deviceRelations->Count; i++) {
pdoExt = &((PHIDCLASS_DEVICE_EXTENSION) fdoExt->deviceRelations->Objects[i]->DeviceExtension)->pdoExt;
//
// Resend all power delayed IRPs
//
count = DequeueAllPdoPowerDelayedIrps(pdoExt, &dequeue);
DBGVERBOSE(("dequeued %d requests\n", count));
while (!IsListEmpty(&dequeue)) {
entry = RemoveHeadList(&dequeue);
delayedIrp = CONTAINING_RECORD(entry, IRP, Tail.Overlay.ListEntry);
stack = IoGetCurrentIrpStackLocation(delayedIrp);
DBGINFO(("resending %x to pdo %x in idle completion.\n", delayedIrp, pdoExt->pdo));
pdoExt->pdo->DriverObject->
MajorFunction[stack->MajorFunction]
(pdoExt->pdo, delayedIrp);
}
}
}
/*
* We cancelled this IRP.
* REGARDLESS of whether this IRP was actually completed by
* the cancel routine or not
* (i.e. regardless of the completion status)
* set this event so that stuff can exit.
* Don't touch the irp again.
*/
DBGINFO(("Set done event."))
KeSetEvent(&fdoExt->idleDoneEvent, 0, FALSE);
return STATUS_MORE_PROCESSING_REQUIRED;
}
break;
}
return STATUS_MORE_PROCESSING_REQUIRED;
}
VOID
HidpIdleTimeWorker(
PDEVICE_OBJECT DeviceObject,
PIO_WORKITEM Item
)
{
FDO_EXTENSION *fdoExt;
PIO_STACK_LOCATION stack;
PIRP irp = NULL, irpToCancel = NULL;
NTSTATUS status;
KIRQL irql;
fdoExt = &((PHIDCLASS_DEVICE_EXTENSION) DeviceObject->DeviceExtension)->fdoExt;
DBGINFO(("fdo 0x%x can idle out", fdoExt->fdo));
irp = fdoExt->idleNotificationRequest;
ASSERT(ISPTR(irp));
if (ISPTR(irp)) {
USHORT PacketSize;
CCHAR StackSize;
UCHAR AllocationFlags;
// Did anyone forget to pull their cancel routine?
ASSERT(irp->CancelRoutine == NULL) ;
AllocationFlags = irp->AllocationFlags;
StackSize = irp->StackCount;
PacketSize = IoSizeOfIrp(StackSize);
IoInitializeIrp(irp, PacketSize, StackSize);
irp->AllocationFlags = AllocationFlags;
irp->Cancel = FALSE;
irp->IoStatus.Status = STATUS_NOT_SUPPORTED;
stack = IoGetNextIrpStackLocation(irp);
stack->MajorFunction = IRP_MJ_INTERNAL_DEVICE_CONTROL;
stack->Parameters.DeviceIoControl.IoControlCode = IOCTL_HID_SEND_IDLE_NOTIFICATION_REQUEST;
stack->Parameters.DeviceIoControl.InputBufferLength = sizeof(fdoExt->idleCallbackInfo);
stack->Parameters.DeviceIoControl.Type3InputBuffer = (PVOID) &(fdoExt->idleCallbackInfo);
//
// Hook a completion routine for when the device completes.
//
IoSetCompletionRoutine(irp,
HidpIdleNotificationRequestComplete,
DeviceObject->DeviceExtension,
TRUE,
TRUE,
TRUE);
//
// The hub will fail this request if the hub doesn't support selective
// suspend. By returning FALSE we remove ourselves from the
//
status = HidpCallDriver(fdoExt->fdo, irp);
KeAcquireSpinLock(&fdoExt->idleNotificationSpinLock, &irql);
if (status == STATUS_PENDING &&
fdoExt->idleCancelling) {
irpToCancel = irp;
}
KeReleaseSpinLock(&fdoExt->idleNotificationSpinLock, irql);
if (irpToCancel) {
IoCancelIrp(irpToCancel);
}
}
IoFreeWorkItem(Item);
}
BOOLEAN HidpStartIdleTimeout(
FDO_EXTENSION *fdoExt,
BOOLEAN DeviceStart
)
{
DEVICE_POWER_STATE deviceWakeableState = PowerDeviceUnspecified;
USHORT deviceUsagePage, deviceUsage;
USHORT usagePage, usage;
ULONG iList, iDesc, iPdo;
HANDLE hKey;
NTSTATUS status;
ULONG enabled;
ULONG length;
UNICODE_STRING s;
KEY_VALUE_PARTIAL_INFORMATION partial;
PHID_IDLE_DEVICE_INFO info;
PLIST_ENTRY entry = NULL;
PULONG idleTimeoutAddress;
if (fdoExt->idleState != IdleDisabled) {
//
// We're already registered for idle detection.
//
return TRUE;
}
//
// If we can't wake the machine, forget about it
//
if (fdoExt->deviceCapabilities.SystemWake == PowerSystemUnspecified) {
DBGVERBOSE(("Can't wake the system with these caps! Disabling SS."));
return FALSE;
}
//
// If D1Latency, D2Latency, D3Latency are ever filled in, perhaps we should
// let these values help us determine which low power state to go to
//
deviceWakeableState = fdoExt->deviceCapabilities.DeviceWake;
DBGVERBOSE(("DeviceWakeableState is D%d", deviceWakeableState-1));
if (deviceWakeableState == PowerDeviceUnspecified) {
DBGVERBOSE(("Due to devcaps, can't idle wake from any state! Disabling SS."));
return FALSE;
}
if (DeviceStart) {
//
// Open the registry and make sure that the
// SelectiveSuspendEnabled value is set to 1.
//
// predispose to failure.
fdoExt->idleEnabledInRegistry = FALSE;
if (!NT_SUCCESS(IoOpenDeviceRegistryKey(fdoExt->collectionPdoExtensions[0]->hidExt.PhysicalDeviceObject,
PLUGPLAY_REGKEY_DEVICE,
STANDARD_RIGHTS_READ,
&hKey))) {
DBGVERBOSE(("Couldn't open device key to check for idle timeout value. Disabling SS."));
return FALSE;
}
RtlInitUnicodeString(&s, HIDCLASS_SELECTIVE_SUSPEND_ON);
status = ZwQueryValueKey(hKey,
&s,
KeyValuePartialInformation,
&partial,
sizeof(KEY_VALUE_PARTIAL_INFORMATION),
&length);
if (!NT_SUCCESS(status)) {
DBGVERBOSE(("ZwQueryValueKey failed for fdo %x. Default to SS turned on if enabled.", fdoExt->fdo));
fdoExt->idleEnabled = TRUE;
} else if (!partial.Data[0]) {
DBGINFO(("Selective suspend is not turned on for this device."));
fdoExt->idleEnabled = FALSE;
} else {
fdoExt->idleEnabled = TRUE;
}
RtlInitUnicodeString(&s, HIDCLASS_SELECTIVE_SUSPEND_ENABLED);
status = ZwQueryValueKey(hKey,
&s,
KeyValuePartialInformation,
&partial,
sizeof(KEY_VALUE_PARTIAL_INFORMATION),
&length);
ZwClose(hKey);
if (!NT_SUCCESS(status)) {
DBGVERBOSE(("ZwQueryValueKey failed for fdo %x. Disabling SS.", fdoExt->fdo));
return FALSE;
}
DBGASSERT(partial.Type == REG_BINARY, ("Registry key wrong type"), FALSE);
if (!partial.Data[0]) {
DBGINFO(("Selective suspend is not enabled for this device in the hive. Disabling SS."));
return FALSE;
}
fdoExt->idleEnabledInRegistry = TRUE;
status = IoWMIRegistrationControl(fdoExt->fdo,
WMIREG_ACTION_REGISTER);
ASSERT(NT_SUCCESS(status));
}
if (!fdoExt->idleEnabledInRegistry || !fdoExt->idleEnabled) {
return FALSE;
}
DBGVERBOSE(("There are %d PDOs on FDO 0x%x",
fdoExt->deviceDesc.CollectionDescLength,
fdoExt));
ASSERT(ISPTR(fdoExt->deviceRelations));
//
// OK, we can selectively suspend this device.
// Allocate and initialize everything, then register.
//
fdoExt->idleNotificationRequest = IoAllocateIrp(fdoExt->fdo->StackSize, FALSE);
if (fdoExt->idleNotificationRequest == NULL) {
DBGWARN(("Failed to allocate idle notification irp"))
return FALSE;
}
status = HidpRegisterDeviceForIdleDetection(fdoExt->fdo,
HID_DEFAULT_IDLE_TIME,
&fdoExt->idleTimeoutValue);
if (STATUS_SUCCESS == status) {
//
// We have successfully registered all device for idle detection,
// send a WW irp down the FDO stack
//
fdoExt->idleState = IdleWaiting;
return TRUE;
} else {
//
// We're already registered? Or did the alloc fail?
//
DBGSUCCESS(status, TRUE);
return FALSE;
}
}
NTSTATUS
HidpCheckIdleState(
PHIDCLASS_DEVICE_EXTENSION HidDeviceExtension,
PIRP Irp
)
{
KIRQL irql;
LONG idleState;
PFDO_EXTENSION fdoExt = &HidDeviceExtension->pdoExt.deviceFdoExt->fdoExt;
NTSTATUS status = STATUS_SUCCESS;
BOOLEAN cancelIdleIrp = FALSE;
ASSERT(HidDeviceExtension->isClientPdo);
KeAcquireSpinLock(&fdoExt->idleNotificationSpinLock, &irql);
if (fdoExt->idleState == IdleWaiting ||
fdoExt->idleState == IdleDisabled) {
//
// Done.
//
if (ISPTR(fdoExt->idleTimeoutValue) &&
fdoExt->idleState == IdleWaiting) {
InterlockedExchange(fdoExt->idleTimeoutValue, 0);
}
KeReleaseSpinLock(&fdoExt->idleNotificationSpinLock, irql);
return STATUS_SUCCESS;
}
DBGINFO(("CheckIdleState on fdo %x", fdoExt->fdo))
status = EnqueuePowerDelayedIrp(HidDeviceExtension, Irp);
if (STATUS_PENDING != status) {
KeReleaseSpinLock(&fdoExt->idleNotificationSpinLock, irql);
return status;
}
fdoExt->idleCancelling = TRUE;
idleState = fdoExt->idleState;
switch (idleState) {
case IdleWaiting:
// bugbug.
// How'd this happen? We already tried this...
TRAP;
break;
case IdleIrpSent:
case IdleCallbackReceived:
case IdleComplete:
cancelIdleIrp = TRUE;
break;
case IdleDisabled:
//
// Shouldn't get here.
//
DBGERR(("Already disabled."));
}
KeReleaseSpinLock(&fdoExt->idleNotificationSpinLock, irql);
if (cancelIdleIrp) {
IoCancelIrp(fdoExt->idleNotificationRequest);
}
return status;
}
VOID
HidpSetDeviceBusy(PFDO_EXTENSION fdoExt)
{
KIRQL irql;
BOOLEAN cancelIdleIrp = FALSE;
LONG idleState;
KeAcquireSpinLock(&fdoExt->idleNotificationSpinLock, &irql);
if (fdoExt->idleState == IdleWaiting ||
fdoExt->idleState == IdleDisabled ||
fdoExt->idleCancelling) {
if (ISPTR(fdoExt->idleTimeoutValue) &&
fdoExt->idleState == IdleWaiting) {
InterlockedExchange(fdoExt->idleTimeoutValue, 0);
fdoExt->idleCancelling = FALSE;
}
//
// Done.
//
KeReleaseSpinLock(&fdoExt->idleNotificationSpinLock, irql);
return;
}
fdoExt->idleCancelling = TRUE;
DBGVERBOSE(("HidpSetDeviceBusy on fdo %x", fdoExt->fdo))
idleState = fdoExt->idleState;
switch (idleState) {
case IdleWaiting:
// bugbug.
// How'd this happen? We already tried this...
TRAP;
break;
case IdleIrpSent:
case IdleCallbackReceived:
case IdleComplete:
cancelIdleIrp = TRUE;
break;
case IdleDisabled:
//
// Shouldn't get here.
//
DBGERR(("Already disabled."));
}
KeReleaseSpinLock(&fdoExt->idleNotificationSpinLock, irql);
if (cancelIdleIrp) {
IoCancelIrp(fdoExt->idleNotificationRequest);
}
}
VOID
HidpCancelIdleNotification(
PFDO_EXTENSION fdoExt,
BOOLEAN removing // Whether this is happening on a remove device
)
{
KIRQL irql;
BOOLEAN cancelIdleIrp = FALSE;
LONG idleState;
NTSTATUS status;
DBGVERBOSE(("Cancelling idle notification for fdo 0x%x", fdoExt->fdo));
status = HidpRegisterDeviceForIdleDetection(fdoExt->fdo, 0, &fdoExt->idleTimeoutValue);
KeAcquireSpinLock(&fdoExt->idleNotificationSpinLock, &irql);
InterlockedCompareExchange(&fdoExt->idleState,
IdleDisabled,
IdleWaiting);
if (fdoExt->idleState == IdleDisabled) {
DBGVERBOSE(("Was waiting or already disabled. Exitting."))
//
// Done.
//
KeReleaseSpinLock(&fdoExt->idleNotificationSpinLock, irql);
return;
}
fdoExt->idleCancelling = TRUE;
idleState = fdoExt->idleState;
DBGINFO(("Wait routine..."))
switch (idleState) {
case IdleWaiting:
// How'd this happen? We already tried this...
TRAP;
break;
case IdleIrpSent:
case IdleCallbackReceived:
// FUlly idled.
case IdleComplete:
cancelIdleIrp = TRUE;
break;
case IdleDisabled:
//
// Shouldn't get here.
//
TRAP;
}
KeReleaseSpinLock(&fdoExt->idleNotificationSpinLock, irql);
if (cancelIdleIrp) {
// Don't need to check the return status of IoCancel, since we'll
// be waiting for the idleDoneEvent.
IoCancelIrp(fdoExt->idleNotificationRequest);
}
if (removing) {
DBGINFO(("Removing fdo %x. Must wait", fdoExt->fdo))
/*
* Cancelling the IRP causes a lower driver to
* complete it (either in a cancel routine or when
* the driver checks Irp->Cancel just before queueing it).
* Wait for the IRP to actually get cancelled.
*/
KeWaitForSingleObject( &fdoExt->idleDoneEvent,
Executive, // wait reason
KernelMode,
FALSE, // not alertable
NULL ); // no timeout
}
DBGINFO(("Done cancelling idle notification on fdo %x", fdoExt->fdo))
idleState = InterlockedExchange(&fdoExt->idleState, IdleDisabled);
ASSERT(fdoExt->idleState == IdleDisabled);
}