Sample Code
Windows Driver Samples/ fastfat File System Driver/ C++/ volinfo.c/
/*++
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
);
NTSTATUS
FatQueryFsSectorSizeInfo (
_In_ PIRP_CONTEXT IrpContext,
_In_ PVCB Vcb,
_Out_writes_bytes_(*Length) PFILE_FS_SECTOR_SIZE_INFORMATION Buffer,
_Inout_ PULONG Length
);
#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)
#pragma alloc_text(PAGE, FatQueryFsSectorSizeInfo)
#endif
_Function_class_(IRP_MJ_QUERY_VOLUME_INFORMATION)
_Function_class_(DRIVER_DISPATCH)
NTSTATUS
FatFsdQueryVolumeInformation (
_In_ PVOLUME_DEVICE_OBJECT VolumeDeviceObject,
_Inout_ 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;
PAGED_CODE();
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;
}
_Function_class_(IRP_MJ_SET_VOLUME_INFORMATION)
_Function_class_(DRIVER_DISPATCH)
NTSTATUS
FatFsdSetVolumeInformation (
_In_ PVOLUME_DEVICE_OBJECT VolumeDeviceObject,
_Inout_ 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;
PAGED_CODE();
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;
}
_Requires_lock_held_(_Global_critical_region_)
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 = STATUS_SUCCESS;
PIO_STACK_LOCATION IrpSp;
PVCB Vcb;
PFCB Fcb;
PCCB Ccb;
ULONG Length;
FS_INFORMATION_CLASS FsInformationClass;
PVOID Buffer;
BOOLEAN WeAcquiredVcb = FALSE;
PAGED_CODE();
//
// 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 );
NT_ASSERT( Vcb != NULL );
_Analysis_assume_( 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;
#if (NTDDI_VERSION >= NTDDI_WIN8)
case FileFsSectorSizeInformation:
Status = FatQueryFsSectorSizeInfo( IrpContext, Vcb, Buffer, &Length );
break;
#endif
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;
}
_Requires_lock_held_(_Global_critical_region_)
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 = STATUS_SUCCESS;
PIO_STACK_LOCATION IrpSp;
PVCB Vcb;
PFCB Fcb;
PCCB Ccb;
TYPE_OF_OPEN TypeOfOpen;
FS_INFORMATION_CLASS FsInformationClass;
PVOID Buffer;
PAGED_CODE();
//
// 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
//
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;
PAGED_CODE();
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 );
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
--*/
{
PAGED_CODE();
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
--*/
{
PAGED_CODE();
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;
PAGED_CODE();
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
--*/
{
PAGED_CODE();
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;
PAGED_CODE();
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 = (PCHAR)&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,
(PVBO)&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 );
NT_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,
(PVBO)&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;
NT_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;
}
#if (NTDDI_VERSION >= NTDDI_WIN8)
NTSTATUS
FatQueryFsSectorSizeInfo (
_In_ PIRP_CONTEXT IrpContext,
_In_ PVCB Vcb,
_Out_writes_bytes_(*Length) PFILE_FS_SECTOR_SIZE_INFORMATION Buffer,
_Inout_ PULONG Length
)
/*++
Routine Description:
This routine implements the query sector size information call
This operation will work on any handle and requires no privilege.
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 receives the remaining bytes free in the buffer
Return Value:
NTSTATUS - Returns the status for the query
--*/
{
NTSTATUS Status;
PAGED_CODE();
UNREFERENCED_PARAMETER( IrpContext );
//
// Sufficient buffer size is guaranteed by the I/O manager or the
// originating kernel mode driver.
//
ASSERT( *Length >= sizeof( FILE_FS_SECTOR_SIZE_INFORMATION ));
_Analysis_assume_( *Length >= sizeof( FILE_FS_SECTOR_SIZE_INFORMATION ));
//
// Retrieve the sector size information
//
Status = FsRtlGetSectorSizeInformation( Vcb->Vpb->RealDevice,
Buffer );
//
// Adjust the length variable
//
if (NT_SUCCESS( Status )) {
*Length -= sizeof( FILE_FS_SECTOR_SIZE_INFORMATION );
}
return Status;
}
#endif
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