volinfo.c

winddk src目录下的文件系统驱动源码压缩!

/*++

Copyright (c) 1989-2000 Microsoft Corporation

Module Name:

    VolInfo.c

Abstract:

    This module implements the volume information routines for Fat called by
    the dispatch driver.


--*/

#include "FatProcs.h"

//
//  The local debug trace level
//

#define Dbg                              (DEBUG_TRACE_VOLINFO)

NTSTATUS
FatQueryFsVolumeInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PVCB Vcb,
    IN PFILE_FS_VOLUME_INFORMATION Buffer,
    IN OUT PULONG Length
    );

NTSTATUS
FatQueryFsSizeInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PVCB Vcb,
    IN PFILE_FS_SIZE_INFORMATION Buffer,
    IN OUT PULONG Length
    );

NTSTATUS
FatQueryFsDeviceInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PVCB Vcb,
    IN PFILE_FS_DEVICE_INFORMATION Buffer,
    IN OUT PULONG Length
    );

NTSTATUS
FatQueryFsAttributeInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PVCB Vcb,
    IN PFILE_FS_ATTRIBUTE_INFORMATION Buffer,
    IN OUT PULONG Length
    );

NTSTATUS
FatQueryFsFullSizeInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PVCB Vcb,
    IN PFILE_FS_FULL_SIZE_INFORMATION Buffer,
    IN OUT PULONG Length
    );
 
NTSTATUS
FatSetFsLabelInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PVCB Vcb,
    IN PFILE_FS_LABEL_INFORMATION Buffer
    );


#ifdef ALLOC_PRAGMA
#pragma alloc_text(PAGE, FatCommonQueryVolumeInfo)
#pragma alloc_text(PAGE, FatCommonSetVolumeInfo)
#pragma alloc_text(PAGE, FatFsdQueryVolumeInformation)
#pragma alloc_text(PAGE, FatFsdSetVolumeInformation)
#pragma alloc_text(PAGE, FatQueryFsAttributeInfo)
#pragma alloc_text(PAGE, FatQueryFsDeviceInfo)
#pragma alloc_text(PAGE, FatQueryFsSizeInfo)
#pragma alloc_text(PAGE, FatQueryFsVolumeInfo)
#pragma alloc_text(PAGE, FatQueryFsFullSizeInfo)
#pragma alloc_text(PAGE, FatSetFsLabelInfo)
#endif


NTSTATUS
FatFsdQueryVolumeInformation (
    IN PVOLUME_DEVICE_OBJECT VolumeDeviceObject,
    IN PIRP Irp
    )

/*++

Routine Description:

    This routine implements the Fsd part of the NtQueryVolumeInformation API
    call.

Arguments:

    VolumeDeviceObject - Supplies the volume device object where the file
        being queried exists.

    Irp - Supplies the Irp being processed.

Return Value:

    NTSTATUS - The FSD status for the Irp.

--*/

{
    NTSTATUS Status;
    PIRP_CONTEXT IrpContext = NULL;

    BOOLEAN TopLevel;

    DebugTrace(+1, Dbg, "FatFsdQueryVolumeInformation\n", 0);

    //
    //  Call the common query routine, with blocking allowed if synchronous
    //

    FsRtlEnterFileSystem();

    TopLevel = FatIsIrpTopLevel( Irp );

    try {

        IrpContext = FatCreateIrpContext( Irp, CanFsdWait( Irp ) );

        Status = FatCommonQueryVolumeInfo( IrpContext, Irp );

    } except(FatExceptionFilter( IrpContext, GetExceptionInformation() )) {

        //
        //  We had some trouble trying to perform the requested
        //  operation, so we'll abort the I/O request with
        //  the error status that we get back from the
        //  execption code
        //

        Status = FatProcessException( IrpContext, Irp, GetExceptionCode() );
    }

    if (TopLevel) { IoSetTopLevelIrp( NULL ); }

    FsRtlExitFileSystem();

    //
    //  And return to our caller
    //

    DebugTrace(-1, Dbg, "FatFsdQueryVolumeInformation -> %08lx\n", Status);

    UNREFERENCED_PARAMETER( VolumeDeviceObject );

    return Status;
}


NTSTATUS
FatFsdSetVolumeInformation (
    IN PVOLUME_DEVICE_OBJECT VolumeDeviceObject,
    IN PIRP Irp
    )

/*++

Routine Description:

    This routine implements the FSD part of the NtSetVolumeInformation API
    call.

Arguments:

    VolumeDeviceObject - Supplies the volume device object where the file
        being set exists.

    Irp - Supplies the Irp being processed.

Return Value:

    NTSTATUS - The FSD status for the Irp.

--*/

{
    NTSTATUS Status;
    PIRP_CONTEXT IrpContext = NULL;

    BOOLEAN TopLevel;

    DebugTrace(+1, Dbg, "FatFsdSetVolumeInformation\n", 0);

    //
    //  Call the common set routine
    //

    FsRtlEnterFileSystem();

    TopLevel = FatIsIrpTopLevel( Irp );

    try {

        IrpContext = FatCreateIrpContext( Irp, CanFsdWait( Irp ) );

        Status = FatCommonSetVolumeInfo( IrpContext, Irp );

    } except(FatExceptionFilter( IrpContext, GetExceptionInformation() )) {

        //
        //  We had some trouble trying to perform the requested
        //  operation, so we'll abort the I/O request with
        //  the error status that we get back from the
        //  execption code
        //

        Status = FatProcessException( IrpContext, Irp, GetExceptionCode() );
    }

    if (TopLevel) { IoSetTopLevelIrp( NULL ); }

    FsRtlExitFileSystem();

    //
    //  And return to our caller
    //

    DebugTrace(-1, Dbg, "FatFsdSetVolumeInformation -> %08lx\n", Status);

    UNREFERENCED_PARAMETER( VolumeDeviceObject );

    return Status;
}


NTSTATUS
FatCommonQueryVolumeInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PIRP Irp
    )

/*++

Routine Description:

    This is the common routine for querying volume information called by both
    the fsd and fsp threads.

Arguments:

    Irp - Supplies the Irp being processed

Return Value:

    NTSTATUS - The return status for the operation

--*/

{
    NTSTATUS Status;
    PIO_STACK_LOCATION IrpSp;

    PVCB Vcb;
    PFCB Fcb;
    PCCB Ccb;

    ULONG Length;
    FS_INFORMATION_CLASS FsInformationClass;
    PVOID Buffer;

    BOOLEAN WeAcquiredVcb = FALSE;

    //
    //  Get the current stack location
    //

    IrpSp = IoGetCurrentIrpStackLocation( Irp );

    DebugTrace(+1, Dbg, "FatCommonQueryVolumeInfo...\n", 0);
    DebugTrace( 0, Dbg, "Irp                  = %08lx\n", Irp );
    DebugTrace( 0, Dbg, "->Length             = %08lx\n", IrpSp->Parameters.QueryVolume.Length);
    DebugTrace( 0, Dbg, "->FsInformationClass = %08lx\n", IrpSp->Parameters.QueryVolume.FsInformationClass);
    DebugTrace( 0, Dbg, "->Buffer             = %08lx\n", Irp->AssociatedIrp.SystemBuffer);

    //
    //  Reference our input parameters to make things easier
    //

    Length = IrpSp->Parameters.QueryVolume.Length;
    FsInformationClass = IrpSp->Parameters.QueryVolume.FsInformationClass;
    Buffer = Irp->AssociatedIrp.SystemBuffer;

    //
    //  Decode the file object to get the Vcb
    //

    (VOID) FatDecodeFileObject( IrpSp->FileObject, &Vcb, &Fcb, &Ccb );

    ASSERT( Vcb != NULL );

    try {

        //
        //  Make sure the vcb is in a usable condition.  This will raise
        //  and error condition if the volume is unusable
        //
        //  Also verify the Root Dcb since we need info from there.
        //

        FatVerifyFcb( IrpContext, Vcb->RootDcb );

        //
        //  Based on the information class we'll do different actions.  Each
        //  of the procedures that we're calling fills up the output buffer
        //  if possible and returns true if it successfully filled the buffer
        //  and false if it couldn't wait for any I/O to complete.
        //

        switch (FsInformationClass) {

        case FileFsVolumeInformation:

            //
            //  This is the only routine we need the Vcb shared because of
            //  copying the volume label.  All other routines copy fields that
            //  cannot change or are just manifest constants.
            //

            if (!FatAcquireSharedVcb( IrpContext, Vcb )) {

                DebugTrace(0, Dbg, "Cannot acquire Vcb\n", 0);

                Status = FatFsdPostRequest( IrpContext, Irp );
                IrpContext = NULL;
                Irp = NULL;

            } else {

                WeAcquiredVcb = TRUE;
                
                Status = FatQueryFsVolumeInfo( IrpContext, Vcb, Buffer, &Length );
            }

            break;

        case FileFsSizeInformation:

            Status = FatQueryFsSizeInfo( IrpContext, Vcb, Buffer, &Length );
            break;

        case FileFsDeviceInformation:

            Status = FatQueryFsDeviceInfo( IrpContext, Vcb, Buffer, &Length );
            break;

        case FileFsAttributeInformation:

            Status = FatQueryFsAttributeInfo( IrpContext, Vcb, Buffer, &Length );
            break;

        case FileFsFullSizeInformation:

            Status = FatQueryFsFullSizeInfo( IrpContext, Vcb, Buffer, &Length );
            break;

        default:

            Status = STATUS_INVALID_PARAMETER;
            break;
        }

        //
        //  Set the information field to the number of bytes actually filled in.
        //

        if (Irp != NULL) {
            
            Irp->IoStatus.Information = IrpSp->Parameters.QueryVolume.Length - Length;
        }

    } finally {

        DebugUnwind( FatCommonQueryVolumeInfo );

        if ( WeAcquiredVcb ) { FatReleaseVcb( IrpContext, Vcb ); }

        if (!AbnormalTermination()) {

            FatCompleteRequest( IrpContext, Irp, Status );
        }

        DebugTrace(-1, Dbg, "FatCommonQueryVolumeInfo -> %08lx\n", Status);
    }

    return Status;
}


NTSTATUS
FatCommonSetVolumeInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PIRP Irp
    )

/*++

Routine Description:

    This is the common routine for setting Volume Information called by both
    the fsd and fsp threads.

Arguments:

    Irp - Supplies the Irp being processed

Return Value:

    NTSTATUS - The return status for the operation

--*/

{
    NTSTATUS Status;
    PIO_STACK_LOCATION IrpSp;

    PVCB Vcb;
    PFCB Fcb;
    PCCB Ccb;
    TYPE_OF_OPEN TypeOfOpen;

    ULONG Length;
    FS_INFORMATION_CLASS FsInformationClass;
    PVOID Buffer;

    //
    //  Get the current stack location
    //

    IrpSp = IoGetCurrentIrpStackLocation( Irp );

    DebugTrace(+1, Dbg, "FatCommonSetVolumeInfo...\n", 0);
    DebugTrace( 0, Dbg, "Irp                  = %08lx\n", Irp );
    DebugTrace( 0, Dbg, "->Length             = %08lx\n", IrpSp->Parameters.SetVolume.Length);
    DebugTrace( 0, Dbg, "->FsInformationClass = %08lx\n", IrpSp->Parameters.SetVolume.FsInformationClass);
    DebugTrace( 0, Dbg, "->Buffer             = %08lx\n", Irp->AssociatedIrp.SystemBuffer);

    //
    //  Reference our input parameters to make things easier
    //

    Length = IrpSp->Parameters.SetVolume.Length;
    FsInformationClass = IrpSp->Parameters.SetVolume.FsInformationClass;
    Buffer = Irp->AssociatedIrp.SystemBuffer;

    //
    //  Decode the file object to get the Vcb
    //

    TypeOfOpen = FatDecodeFileObject( IrpSp->FileObject, &Vcb, &Fcb, &Ccb );

    if (TypeOfOpen != UserVolumeOpen) {

        FatCompleteRequest( IrpContext, Irp, STATUS_ACCESS_DENIED );

        DebugTrace(-1, Dbg, "FatCommonSetVolumeInfo -> STATUS_ACCESS_DENIED\n", 0);

        return STATUS_ACCESS_DENIED;
    }

    //
    //  Acquire exclusive access to the Vcb and enqueue the Irp if we didn't
    //  get access
    //

    if (!FatAcquireExclusiveVcb( IrpContext, Vcb )) {

        DebugTrace(0, Dbg, "Cannot acquire Vcb\n", 0);

        Status = FatFsdPostRequest( IrpContext, Irp );

        DebugTrace(-1, Dbg, "FatCommonSetVolumeInfo -> %08lx\n", Status );
        return Status;
    }

    try {

        //
        //  Make sure the vcb is in a usable condition.  This will raise
        //  and error condition if the volume is unusable
        //
        //  Also verify the Root Dcb since we need info from there.
        //

        FatVerifyFcb( IrpContext, Vcb->RootDcb );

        //
        //  Based on the information class we'll do different actions.  Each
        //  of the procedures that we're calling performs the action if
        //  possible and returns true if it successful and false if it couldn't
        //  wait for any I/O to complete.
        //

        switch (FsInformationClass) {

        case FileFsLabelInformation:

            Status = FatSetFsLabelInfo( IrpContext, Vcb, Buffer );
            break;

        default:

            Status = STATUS_INVALID_PARAMETER;
            break;
        }

        FatUnpinRepinnedBcbs( IrpContext );

    } finally {

        DebugUnwind( FatCommonSetVolumeInfo );

        FatReleaseVcb( IrpContext, Vcb );

        if (!AbnormalTermination()) {

            FatCompleteRequest( IrpContext, Irp, Status );
        }

        DebugTrace(-1, Dbg, "FatCommonSetVolumeInfo -> %08lx\n", Status);
    }

    return Status;
}


//
//  Internal support routine
//

NTSTATUS
FatQueryFsVolumeInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PVCB Vcb,
    IN PFILE_FS_VOLUME_INFORMATION Buffer,
    IN OUT PULONG Length
    )

/*++

Routine Description:

    This routine implements the query volume info call

Arguments:

    Vcb - Supplies the Vcb being queried

    Buffer - Supplies a pointer to the output buffer where the information
        is to be returned

    Length - Supplies the length of the buffer in byte.  This variable
        upon return recieves the remaining bytes free in the buffer

Return Value:

    NTSTATUS - Returns the status for the query

--*/

{
    ULONG BytesToCopy;

    NTSTATUS Status;

    DebugTrace(0, Dbg, "FatQueryFsVolumeInfo...\n", 0);

    //
    //  Zero out the buffer, then extract and fill up the non zero fields.
    //

    RtlZeroMemory( Buffer, sizeof(FILE_FS_VOLUME_INFORMATION) );

    Buffer->VolumeSerialNumber = Vcb->Vpb->SerialNumber;

    Buffer->SupportsObjects = FALSE;

    *Length -= FIELD_OFFSET(FILE_FS_VOLUME_INFORMATION, VolumeLabel[0]);

    //
    //  Check if the buffer we're given is long enough
    //

    if ( *Length >= (ULONG)Vcb->Vpb->VolumeLabelLength ) {

        BytesToCopy = Vcb->Vpb->VolumeLabelLength;

        Status = STATUS_SUCCESS;

    } else {

        BytesToCopy = *Length;

        Status = STATUS_BUFFER_OVERFLOW;
    }

    //
    //  Copy over what we can of the volume label, and adjust *Length
    //

    Buffer->VolumeLabelLength = Vcb->Vpb->VolumeLabelLength;

    RtlCopyMemory( &Buffer->VolumeLabel[0],
                   &Vcb->Vpb->VolumeLabel[0],
                   BytesToCopy );

    *Length -= BytesToCopy;

    //
    //  Set our status and return to our caller
    //

    UNREFERENCED_PARAMETER( IrpContext );