usage.c File Reference

#include <pci.h>
#include <debug.h>

Include dependency graph for usage.c:

Go to the source code of this file.

Macros
#define	NDEBUG

Functions
NTSTATUS NTAPI	PciUpdateDeviceUsage (_Inout_ PPCI_POWER_STATE PowerState, _In_ PIO_STACK_LOCATION IoStackLocation)
	Counts a paging, hibernation or dump file arriving on or leaving a device.
NTSTATUS NTAPI	PciSendDeviceUsageToParent (_In_ PPCI_FDO_EXTENSION ParentFdoExtension, _In_ PIO_STACK_LOCATION IoStackLocation)
	Sends a device usage notification to the top of the stack of a parent bus.

Macro Definition Documentation

NDEBUG

#define NDEBUG

Definition at line 13 of file usage.c.

Function Documentation

PciSendDeviceUsageToParent()

NTSTATUS NTAPI PciSendDeviceUsageToParent	(	_In_ PPCI_FDO_EXTENSION	ParentFdoExtension,
		_In_ PIO_STACK_LOCATION	IoStackLocation
	)

Sends a device usage notification to the top of the stack of a parent bus.

Parameters

[in]	ParentFdoExtension	The FDO extension of the bus the function is on.
[in]	IoStackLocation	The stack location of the notification the function received.

Returns

The status the parent stack completed the notification with.

Definition at line 94 of file usage.c.

{
    PDEVICE_OBJECT TopDevice;
    PIO_STACK_LOCATION NextStack;
    IO_STATUS_BLOCK IoStatus;
    KEVENT Event;
    NTSTATUS Status;
    PIRP Irp;
 
    PAGED_CODE();
 
    TopDevice = IoGetAttachedDeviceReference(ParentFdoExtension->PhysicalDeviceObject);
 
    KeInitializeEvent(&Event, SynchronizationEvent, FALSE);
    Irp = IoBuildSynchronousFsdRequest(IRP_MJ_PNP,
                                       TopDevice,
                                       NULL,
                                       0,
                                       NULL,
                                       &Event,
                                       &IoStatus);
    if (!Irp)
    {
        ObDereferenceObject(TopDevice);
        return STATUS_INSUFFICIENT_RESOURCES;
    }
 
    /* A PnP IRP nobody handles must come back as not supported */
    Irp->IoStatus.Status = STATUS_NOT_SUPPORTED;
    Irp->IoStatus.Information = 0;
 
    NextStack = IoGetNextIrpStackLocation(Irp);
    NextStack->MinorFunction = IRP_MN_DEVICE_USAGE_NOTIFICATION;
    NextStack->Parameters.UsageNotification = IoStackLocation->Parameters.UsageNotification;
 
    Status = IoCallDriver(TopDevice, Irp);
    if (Status == STATUS_PENDING)
    {
        KeWaitForSingleObject(&Event, Executive, KernelMode, FALSE, NULL);
        Status = IoStatus.Status;
    }
 
    ObDereferenceObject(TopDevice);
    return Status;
}

Referenced by PciPdoIrpDeviceUsageNotification().

PciUpdateDeviceUsage()

NTSTATUS NTAPI PciUpdateDeviceUsage	(	_Inout_ PPCI_POWER_STATE	PowerState,
		_In_ PIO_STACK_LOCATION	IoStackLocation
	)

Counts a paging, hibernation or dump file arriving on or leaving a device.

Parameters

[in,out]	PowerState	The power state of the extension that holds the counts.
[in]	IoStackLocation	The stack location of the device usage notification.

Returns

STATUS_SUCCESS for a usage the driver accepts, STATUS_NOT_SUPPORTED otherwise.

Definition at line 35 of file usage.c.

{
    PLONG Count;
 
    PAGED_CODE();
 
    switch (IoStackLocation->Parameters.UsageNotification.Type)
    {
        case DeviceUsageTypePaging:
            Count = &PowerState->Paging;
            break;
 
        case DeviceUsageTypeHibernation:
            Count = &PowerState->Hibernate;
            break;
 
        case DeviceUsageTypeDumpFile:
            Count = &PowerState->CrashDump;
            break;
 
        /* Accepted, but nothing is held back for the boot device */
        case DeviceUsageTypeBoot:
            return STATUS_SUCCESS;
 
        default:
            return STATUS_NOT_SUPPORTED;
    }
 
    /* Several files can share a device, so these are counts and not flags */
    if (IoStackLocation->Parameters.UsageNotification.InPath)
    {
        InterlockedIncrement(Count);
    }
    else
    {
        ASSERT(*Count > 0);
        InterlockedDecrement(Count);
    }
 
    return STATUS_SUCCESS;
}

Referenced by PciFdoIrpDeviceUsageNotification(), and PciPdoIrpDeviceUsageNotification().