volinfo.c

winddk src目录下的文件系统驱动源码压缩!

    return Status;
}


//
//  Internal support routine
//

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

/*++

Routine Description:

    This routine implements the query volume size 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:

    Status - Returns the status for the query

--*/

{
    DebugTrace(0, Dbg, "FatQueryFsSizeInfo...\n", 0);

    RtlZeroMemory( Buffer, sizeof(FILE_FS_SIZE_INFORMATION) );

    //
    //  Set the output buffer.  
    //

    Buffer->TotalAllocationUnits.LowPart =
                                    Vcb->AllocationSupport.NumberOfClusters;
    Buffer->AvailableAllocationUnits.LowPart =
                                    Vcb->AllocationSupport.NumberOfFreeClusters;
  
    Buffer->SectorsPerAllocationUnit = Vcb->Bpb.SectorsPerCluster;
    Buffer->BytesPerSector = Vcb->Bpb.BytesPerSector;

    //
    //  Adjust the length variable
    //

    *Length -= sizeof(FILE_FS_SIZE_INFORMATION);

    //
    //  And return success to our caller
    //

    UNREFERENCED_PARAMETER( IrpContext );

    return STATUS_SUCCESS;
}


//
//  Internal support routine
//

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

/*++

Routine Description:

    This routine implements the query volume device 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:

    Status - Returns the status for the query

--*/

{
    DebugTrace(0, Dbg, "FatQueryFsDeviceInfo...\n", 0);

    RtlZeroMemory( Buffer, sizeof(FILE_FS_DEVICE_INFORMATION) );

    //
    //  Set the output buffer
    //

    Buffer->DeviceType = FILE_DEVICE_DISK;

    Buffer->Characteristics = Vcb->TargetDeviceObject->Characteristics;

    //
    //  Adjust the length variable
    //

    *Length -= sizeof(FILE_FS_DEVICE_INFORMATION);

    //
    //  And return success to our caller
    //

    UNREFERENCED_PARAMETER( IrpContext );

    return STATUS_SUCCESS;
}


//
//  Internal support routine
//

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

/*++

Routine Description:

    This routine implements the query volume attribute 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:

    Status - Returns the status for the query

--*/

{
    ULONG BytesToCopy;

    NTSTATUS Status;

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

    //
    //  Set the output buffer
    //

    Buffer->FileSystemAttributes = FILE_CASE_PRESERVED_NAMES |
                                   FILE_UNICODE_ON_DISK;

    if (FlagOn( Vcb->VcbState, VCB_STATE_FLAG_WRITE_PROTECTED )) {
        
        SetFlag( Buffer->FileSystemAttributes, FILE_READ_ONLY_VOLUME );
    }

    Buffer->MaximumComponentNameLength = FatData.ChicagoMode ? 255 : 12;

    if (FatIsFat32(Vcb)) {

        //
        //  Determine how much of the file system name will fit.
        //
    
        if ( (*Length - FIELD_OFFSET( FILE_FS_ATTRIBUTE_INFORMATION,
                                      FileSystemName[0] )) >= 10 ) {
    
            BytesToCopy = 10;
            *Length -= FIELD_OFFSET( FILE_FS_ATTRIBUTE_INFORMATION,
                                     FileSystemName[0] ) + 10;
            Status = STATUS_SUCCESS;
    
        } else {
    
            BytesToCopy = *Length - FIELD_OFFSET( FILE_FS_ATTRIBUTE_INFORMATION,
                                                  FileSystemName[0]);
            *Length = 0;
    
            Status = STATUS_BUFFER_OVERFLOW;
        }
    
        RtlCopyMemory( &Buffer->FileSystemName[0], L"FAT32", BytesToCopy );

    } else {

        //
        //  Determine how much of the file system name will fit.
        //
    
        if ( (*Length - FIELD_OFFSET( FILE_FS_ATTRIBUTE_INFORMATION,
                                      FileSystemName[0] )) >= 6 ) {
    
            BytesToCopy = 6;
            *Length -= FIELD_OFFSET( FILE_FS_ATTRIBUTE_INFORMATION,
                                     FileSystemName[0] ) + 6;
            Status = STATUS_SUCCESS;
    
        } else {
    
            BytesToCopy = *Length - FIELD_OFFSET( FILE_FS_ATTRIBUTE_INFORMATION,
                                                  FileSystemName[0]);
            *Length = 0;
    
            Status = STATUS_BUFFER_OVERFLOW;
        }
    

        RtlCopyMemory( &Buffer->FileSystemName[0], L"FAT", BytesToCopy );
    }

    Buffer->FileSystemNameLength       = BytesToCopy;

    //
    //  And return success to our caller
    //

    UNREFERENCED_PARAMETER( IrpContext );
    UNREFERENCED_PARAMETER( Vcb );

    return Status;
}


//
//  Internal support routine
//

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

/*++

Routine Description:

    This routine implements the query volume full size 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:

    Status - Returns the status for the query

--*/

{
    DebugTrace(0, Dbg, "FatQueryFsSizeInfo...\n", 0);

    RtlZeroMemory( Buffer, sizeof(FILE_FS_FULL_SIZE_INFORMATION) );

    Buffer->TotalAllocationUnits.LowPart =
                                Vcb->AllocationSupport.NumberOfClusters;
    Buffer->CallerAvailableAllocationUnits.LowPart =
                                Vcb->AllocationSupport.NumberOfFreeClusters;
    Buffer->ActualAvailableAllocationUnits.LowPart =
        Buffer->CallerAvailableAllocationUnits.LowPart;
    Buffer->SectorsPerAllocationUnit = Vcb->Bpb.SectorsPerCluster;
    Buffer->BytesPerSector = Vcb->Bpb.BytesPerSector;

    //
    //  Adjust the length variable
    //

    *Length -= sizeof(FILE_FS_FULL_SIZE_INFORMATION);

    //
    //  And return success to our caller
    //

    UNREFERENCED_PARAMETER( IrpContext );

    return STATUS_SUCCESS;
}


//
//  Internal support routine
//

NTSTATUS
FatSetFsLabelInfo (
    IN PIRP_CONTEXT IrpContext,
    IN PVCB Vcb,
    IN PFILE_FS_LABEL_INFORMATION Buffer
    )

/*++

Routine Description:

    This routine implements the set volume label call

Arguments:

    Vcb - Supplies the Vcb being queried

    Buffer - Supplies the input where the information is stored.

Return Value:

    NTSTATUS - Returns the status for the operation

--*/

{
    NTSTATUS Status;

    PDIRENT Dirent;
    PBCB DirentBcb = NULL;
    ULONG ByteOffset;

    WCHAR TmpBuffer[11];
    UCHAR OemBuffer[11];
    OEM_STRING OemLabel;
    UNICODE_STRING UnicodeString;
    UNICODE_STRING UpcasedLabel;

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

    //
    //  Setup our local variable
    //

    UnicodeString.Length = (USHORT)Buffer->VolumeLabelLength;
    UnicodeString.MaximumLength = UnicodeString.Length;
    UnicodeString.Buffer = (PWSTR) &Buffer->VolumeLabel[0];

    //
    //  Make sure the name can fit into the stack buffer
    //

    if ( UnicodeString.Length > 11*sizeof(WCHAR) ) {

        return STATUS_INVALID_VOLUME_LABEL;
    }

    //
    //  Upcase the name and convert it to the Oem code page.
    //

    OemLabel.Buffer = &OemBuffer[0];
    OemLabel.Length = 0;
    OemLabel.MaximumLength = 11;

    Status = RtlUpcaseUnicodeStringToCountedOemString( &OemLabel,
                                                       &UnicodeString,
                                                       FALSE );

    //
    //  Volume label that fits in 11 unicode character length limit
    //  is not necessary within 11 characters in OEM character set.
    //

    if (!NT_SUCCESS( Status )) {

        DebugTrace(-1, Dbg, "FatSetFsLabelInfo:  Label must be too long. %08lx\n", Status );

        return STATUS_INVALID_VOLUME_LABEL;
    }

    //
    //  Strip spaces off of the label.
    //

    if (OemLabel.Length > 0) {

        USHORT i;
        USHORT LastSpaceIndex = MAXUSHORT;

        //
        //  Check the label for illegal characters
        //

        for ( i = 0; i < (ULONG)OemLabel.Length; i += 1 ) {

            if ( FsRtlIsLeadDbcsCharacter( OemLabel.Buffer[i] ) ) {

                LastSpaceIndex = MAXUSHORT;
                i += 1;
                continue;
            }

            if (!FsRtlIsAnsiCharacterLegalFat(OemLabel.Buffer[i], FALSE) ||
                (OemLabel.Buffer[i] == '.')) {

                return STATUS_INVALID_VOLUME_LABEL;
            }

            //
            //  Watch for the last run of spaces, so we can strip them.
            //

            if (OemLabel.Buffer[i] == ' ' &&
                LastSpaceIndex == MAXUSHORT) {
                LastSpaceIndex = i;
            } else {
                LastSpaceIndex = MAXUSHORT;
            }
        }

        if (LastSpaceIndex != MAXUSHORT) {
            OemLabel.Length = LastSpaceIndex;
        }
    }

    //
    //  Get the Unicode upcased string to store in the VPB.
    //

    UpcasedLabel.Length = UnicodeString.Length;
    UpcasedLabel.MaximumLength = 11*sizeof(WCHAR);
    UpcasedLabel.Buffer = &TmpBuffer[0];

    Status = RtlOemStringToCountedUnicodeString( &UpcasedLabel,
                                                 &OemLabel,
                                                 FALSE );

    if (!NT_SUCCESS( Status )) {

        DebugTrace(-1, Dbg, "FatSetFsLabelInfo:  Label must be too long. %08lx\n", Status );

        return STATUS_INVALID_VOLUME_LABEL;
    }

    DirentBcb = NULL;

    //
    //  Make this look like a write through to disk.  This is important to
    //  avoid a unpleasant window where it looks like we have the wrong volume.
    //

    SetFlag( IrpContext->Flags, IRP_CONTEXT_FLAG_WRITE_THROUGH );

    try {

        //
        //  Are we setting or removing the label?  Note that shaving spaces could
        //  make this different than wondering if the input buffer is non-zero length.
        //
        
        if (OemLabel.Length > 0) {

            //
            //  Locate the volume label if there already is one
            //

            FatLocateVolumeLabel( IrpContext,
                                  Vcb,
                                  &Dirent,
                                  &DirentBcb,
                                  &ByteOffset );

            //
            //  Check that we really got one, if not then we need to create
            //  a new one.  The procedure we call will raise an appropriate
            //  status if we are not able to allocate a new dirent
            //

            if (Dirent == NULL) {

                ByteOffset = FatCreateNewDirent( IrpContext,
                                                 Vcb->RootDcb,
                                                 1 );

                FatPrepareWriteDirectoryFile( IrpContext,
                                              Vcb->RootDcb,
                                              ByteOffset,
                                              sizeof(DIRENT),
                                              &DirentBcb,
                                              &Dirent,
                                              FALSE,
                                              TRUE,
                                              &Status );

                ASSERT( NT_SUCCESS( Status ));
            
            } else {

                //
                //  Just mark this guy dirty now.
                //
            
                FatSetDirtyBcb( IrpContext, DirentBcb, Vcb, TRUE );
            }

            //
            //  Now reconstruct the volume label dirent.
            //

            FatConstructLabelDirent( IrpContext,
                                     Dirent,
                                     &OemLabel );

            //
            //  Unpin the Bcb here so that we will get any IO errors
            //  here before changing the VPB label.
            //

            FatUnpinBcb( IrpContext, DirentBcb );
            FatUnpinRepinnedBcbs( IrpContext );

            //
            //  Now set the upcased label in the VPB
            //

            RtlCopyMemory( &Vcb->Vpb->VolumeLabel[0],
                           &UpcasedLabel.Buffer[0],
                           UpcasedLabel.Length );

            Vcb->Vpb->VolumeLabelLength = UpcasedLabel.Length;

        } else {

            //
            //  Otherwise we're trying to delete the label
            //  Locate the current volume label if there already is one
            //

            FatLocateVolumeLabel( IrpContext,
                                  Vcb,
                                  &Dirent,
                                  &DirentBcb,
                                  &ByteOffset );

            //
            //  Check that we really got one
            //

            if (Dirent == NULL) {

                try_return( Status = STATUS_SUCCESS );
            }

            //
            //  Now delete the current label.
            //

            Dirent->FileName[0] = FAT_DIRENT_DELETED;

            ASSERT( (Vcb->RootDcb->Specific.Dcb.UnusedDirentVbo == 0xffffffff) ||
                    RtlAreBitsSet( &Vcb->RootDcb->Specific.Dcb.FreeDirentBitmap,
                                   ByteOffset / sizeof(DIRENT),
                                   1 ) );

            RtlClearBits( &Vcb->RootDcb->Specific.Dcb.FreeDirentBitmap,
                          ByteOffset / sizeof(DIRENT),
                          1 );

            FatSetDirtyBcb( IrpContext, DirentBcb, Vcb, TRUE );

            //
            //  Unpin the Bcb here so that we will get any IO errors
            //  here before changing the VPB label.
            //

            FatUnpinBcb( IrpContext, DirentBcb );
            FatUnpinRepinnedBcbs( IrpContext );

            //
            //  Now set the label in the VPB
            //

            Vcb->Vpb->VolumeLabelLength = 0;
        }

        Status = STATUS_SUCCESS;

    try_exit: NOTHING;
    } finally {

        DebugUnwind( FatSetFsALabelInfo );

        FatUnpinBcb( IrpContext, DirentBcb );

        DebugTrace(-1, Dbg, "FatSetFsALabelInfo -> STATUS_SUCCESS\n", 0);
    }

    return Status;
}