NTSTATUS VfatDirectoryControl (PVFAT_IRP_CONTEXT IrpContext)
/*
* FUNCTION: directory control : read/write directory informations
*/
{
NTSTATUS RC = STATUS_SUCCESS;
IrpContext->Irp->IoStatus.Information = 0;
switch (IrpContext->MinorFunction)
{
case IRP_MN_QUERY_DIRECTORY:
RC = DoQuery (IrpContext);
break;
case IRP_MN_NOTIFY_CHANGE_DIRECTORY:
DPRINT (" vfat, dir : change\n");
RC = STATUS_NOT_IMPLEMENTED;
break;
default:
// error
DbgPrint ("unexpected minor function %x in VFAT driver\n",
IrpContext->MinorFunction);
RC = STATUS_INVALID_DEVICE_REQUEST;
break;
}
if (RC == STATUS_PENDING)
{
RC = VfatQueueRequest(IrpContext);
}
else
{
IrpContext->Irp->IoStatus.Status = RC;
IoCompleteRequest (IrpContext->Irp, IO_NO_INCREMENT);
VfatFreeIrpContext(IrpContext);
}
return RC;
}
/*
* FUNCTION: Set the specified volume information
*/
NTSTATUS
VfatSetVolumeInformation(
PVFAT_IRP_CONTEXT IrpContext)
{
FS_INFORMATION_CLASS FsInformationClass;
NTSTATUS Status = STATUS_SUCCESS;
PVOID SystemBuffer;
ULONG BufferLength;
PIO_STACK_LOCATION Stack = IrpContext->Stack;
/* PRECONDITION */
ASSERT(IrpContext);
DPRINT("VfatSetVolumeInformation(IrpContext %p)\n", IrpContext);
if (!ExAcquireResourceExclusiveLite(&((PDEVICE_EXTENSION)IrpContext->DeviceObject->DeviceExtension)->DirResource,
(BOOLEAN)(IrpContext->Flags & IRPCONTEXT_CANWAIT)))
{
return VfatQueueRequest(IrpContext);
}
FsInformationClass = Stack->Parameters.SetVolume.FsInformationClass;
BufferLength = Stack->Parameters.SetVolume.Length;
SystemBuffer = IrpContext->Irp->AssociatedIrp.SystemBuffer;
DPRINT("FsInformationClass %d\n", FsInformationClass);
DPRINT("BufferLength %u\n", BufferLength);
DPRINT("SystemBuffer %p\n", SystemBuffer);
switch (FsInformationClass)
{
case FileFsLabelInformation:
Status = FsdSetFsLabelInformation(IrpContext->DeviceObject,
SystemBuffer);
break;
default:
Status = STATUS_NOT_SUPPORTED;
}
ExReleaseResourceLite(&((PDEVICE_EXTENSION)IrpContext->DeviceObject->DeviceExtension)->DirResource);
IrpContext->Irp->IoStatus.Status = Status;
IrpContext->Irp->IoStatus.Information = 0;
IoCompleteRequest(IrpContext->Irp, IO_NO_INCREMENT);
VfatFreeIrpContext(IrpContext);
return Status;
}
/*
* FUNCTION: Closes a file
*/
NTSTATUS
VfatClose(
PVFAT_IRP_CONTEXT IrpContext)
{
NTSTATUS Status;
DPRINT("VfatClose(DeviceObject %p, Irp %p)\n", IrpContext->DeviceObject, IrpContext->Irp);
if (IrpContext->DeviceObject == VfatGlobalData->DeviceObject)
{
DPRINT("Closing file system\n");
Status = STATUS_SUCCESS;
goto ByeBye;
}
#if 0
/* There occurs a dead look at the call to CcRosDeleteFileCache/ObDereferenceObject/VfatClose
in CmLazyCloseThreadMain if VfatClose is execute asynchronous in a worker thread. */
if (!ExAcquireResourceExclusiveLite(&IrpContext->DeviceExt->DirResource, IrpContext->Flags & IRPCONTEXT_CANWAIT))
#else
if (!ExAcquireResourceExclusiveLite(&IrpContext->DeviceExt->DirResource, TRUE))
#endif
{
return VfatQueueRequest(IrpContext);
}
Status = VfatCloseFile(IrpContext->DeviceExt, IrpContext->FileObject);
ExReleaseResourceLite(&IrpContext->DeviceExt->DirResource);
ByeBye:
IrpContext->Irp->IoStatus.Status = Status;
IrpContext->Irp->IoStatus.Information = 0;
IoCompleteRequest(IrpContext->Irp, IO_NO_INCREMENT);
VfatFreeIrpContext(IrpContext);
return Status;
}
NTSTATUS
VfatWrite(
PVFAT_IRP_CONTEXT IrpContext)
{
PVFATFCB Fcb;
PERESOURCE Resource = NULL;
LARGE_INTEGER ByteOffset;
LARGE_INTEGER OldFileSize;
NTSTATUS Status = STATUS_SUCCESS;
ULONG Length = 0;
PVOID Buffer;
ULONG BytesPerSector;
ASSERT(IrpContext);
DPRINT("VfatWrite(IrpContext %p)\n", IrpContext);
ASSERT(IrpContext->DeviceObject);
// This request is not allowed on the main device object
if (IrpContext->DeviceObject == VfatGlobalData->DeviceObject)
{
DPRINT("VfatWrite is called with the main device object.\n");
Status = STATUS_INVALID_DEVICE_REQUEST;
goto ByeBye;
}
ASSERT(IrpContext->DeviceExt);
ASSERT(IrpContext->FileObject);
Fcb = IrpContext->FileObject->FsContext;
ASSERT(Fcb);
if (Fcb->Flags & FCB_IS_PAGE_FILE)
{
PFATINFO FatInfo = &IrpContext->DeviceExt->FatInfo;
IrpContext->Stack->Parameters.Write.ByteOffset.QuadPart += FatInfo->dataStart * FatInfo->BytesPerSector;
IoSkipCurrentIrpStackLocation(IrpContext->Irp);
DPRINT("Write to page file, disk offset %I64x\n", IrpContext->Stack->Parameters.Write.ByteOffset.QuadPart);
Status = IoCallDriver(IrpContext->DeviceExt->StorageDevice, IrpContext->Irp);
VfatFreeIrpContext(IrpContext);
return Status;
}
DPRINT("<%wZ>\n", &Fcb->PathNameU);
/* fail if file is a directory and no paged read */
if (*Fcb->Attributes & FILE_ATTRIBUTE_DIRECTORY && !(IrpContext->Irp->Flags & IRP_PAGING_IO))
{
Status = STATUS_INVALID_PARAMETER;
goto ByeBye;
}
ByteOffset = IrpContext->Stack->Parameters.Write.ByteOffset;
if (ByteOffset.u.LowPart == FILE_WRITE_TO_END_OF_FILE &&
ByteOffset.u.HighPart == -1)
{
ByteOffset.QuadPart = Fcb->RFCB.FileSize.QuadPart;
}
Length = IrpContext->Stack->Parameters.Write.Length;
BytesPerSector = IrpContext->DeviceExt->FatInfo.BytesPerSector;
if (ByteOffset.u.HighPart && !(Fcb->Flags & FCB_IS_VOLUME))
{
Status = STATUS_INVALID_PARAMETER;
goto ByeBye;
}
if (Fcb->Flags & (FCB_IS_FAT | FCB_IS_VOLUME) ||
vfatDirEntryGetFirstCluster(IrpContext->DeviceExt, &Fcb->entry) == 1)
{
if (ByteOffset.QuadPart + Length > Fcb->RFCB.FileSize.QuadPart)
{
// we can't extend the FAT, the volume or the root on FAT12/FAT16
Status = STATUS_END_OF_FILE;
goto ByeBye;
}
}
if (IrpContext->Irp->Flags & (IRP_PAGING_IO|IRP_NOCACHE) || (Fcb->Flags & FCB_IS_VOLUME))
{
if (ByteOffset.u.LowPart % BytesPerSector != 0 || Length % BytesPerSector != 0)
{
// non cached write must be sector aligned
Status = STATUS_INVALID_PARAMETER;
goto ByeBye;
}
}
if (Length == 0)
{
/* FIXME: Update last write time */
IrpContext->Irp->IoStatus.Information = 0;
Status = STATUS_SUCCESS;
goto ByeBye;
}
if (IrpContext->Irp->Flags & IRP_PAGING_IO)
{
if (ByteOffset.u.LowPart + Length > Fcb->RFCB.AllocationSize.u.LowPart)
{
Status = STATUS_INVALID_PARAMETER;
goto ByeBye;
}
if (ByteOffset.u.LowPart + Length > ROUND_UP(Fcb->RFCB.AllocationSize.u.LowPart, BytesPerSector))
{
Length = ROUND_UP(Fcb->RFCB.FileSize.u.LowPart, BytesPerSector) - ByteOffset.u.LowPart;
}
}
if (Fcb->Flags & FCB_IS_VOLUME)
{
Resource = &IrpContext->DeviceExt->DirResource;
}
else if (IrpContext->Irp->Flags & IRP_PAGING_IO)
{
Resource = &Fcb->PagingIoResource;
}
else
{
Resource = &Fcb->MainResource;
}
if (Fcb->Flags & FCB_IS_PAGE_FILE)
{
if (!ExAcquireResourceSharedLite(Resource,
(BOOLEAN)(IrpContext->Flags & IRPCONTEXT_CANWAIT)))
{
Resource = NULL;
Status = STATUS_PENDING;
goto ByeBye;
}
}
else
{
if (!ExAcquireResourceExclusiveLite(Resource,
(BOOLEAN)(IrpContext->Flags & IRPCONTEXT_CANWAIT)))
{
Resource = NULL;
Status = STATUS_PENDING;
goto ByeBye;
}
}
if (!(IrpContext->Irp->Flags & IRP_PAGING_IO) &&
FsRtlAreThereCurrentFileLocks(&Fcb->FileLock))
{
if (!FsRtlCheckLockForWriteAccess(&Fcb->FileLock, IrpContext->Irp))
{
Status = STATUS_FILE_LOCK_CONFLICT;
goto ByeBye;
}
}
if (!(IrpContext->Flags & IRPCONTEXT_CANWAIT) && !(Fcb->Flags & FCB_IS_VOLUME))
{
if (ByteOffset.u.LowPart + Length > Fcb->RFCB.AllocationSize.u.LowPart)
{
Status = STATUS_PENDING;
goto ByeBye;
}
}
OldFileSize = Fcb->RFCB.FileSize;
Buffer = VfatGetUserBuffer(IrpContext->Irp);
if (!Buffer)
{
Status = STATUS_INVALID_USER_BUFFER;
goto ByeBye;
}
if (!(Fcb->Flags & (FCB_IS_FAT|FCB_IS_VOLUME)) &&
!(IrpContext->Irp->Flags & IRP_PAGING_IO) &&
ByteOffset.u.LowPart + Length > Fcb->RFCB.FileSize.u.LowPart)
{
LARGE_INTEGER AllocationSize;
AllocationSize.QuadPart = ByteOffset.u.LowPart + Length;
Status = VfatSetAllocationSizeInformation(IrpContext->FileObject, Fcb,
IrpContext->DeviceExt, &AllocationSize);
if (!NT_SUCCESS (Status))
{
goto ByeBye;
}
}
if (!(IrpContext->Irp->Flags & (IRP_NOCACHE|IRP_PAGING_IO)) &&
!(Fcb->Flags & (FCB_IS_PAGE_FILE|FCB_IS_VOLUME)))
{
// cached write
if (IrpContext->FileObject->PrivateCacheMap == NULL)
{
CcInitializeCacheMap(IrpContext->FileObject,
(PCC_FILE_SIZES)(&Fcb->RFCB.AllocationSize),
FALSE,
&VfatGlobalData->CacheMgrCallbacks,
Fcb);
}
if (ByteOffset.QuadPart > OldFileSize.QuadPart)
{
CcZeroData(IrpContext->FileObject, &OldFileSize, &ByteOffset, TRUE);
}
if (CcCopyWrite(IrpContext->FileObject, &ByteOffset, Length,
1 /*IrpContext->Flags & IRPCONTEXT_CANWAIT*/, Buffer))
{
IrpContext->Irp->IoStatus.Information = Length;
Status = STATUS_SUCCESS;
}
else
{
Status = STATUS_UNSUCCESSFUL;
}
}
else
{
// non cached write
if (ByteOffset.QuadPart > OldFileSize.QuadPart)
{
CcZeroData(IrpContext->FileObject, &OldFileSize, &ByteOffset, TRUE);
}
Status = VfatLockUserBuffer(IrpContext->Irp, Length, IoReadAccess);
if (!NT_SUCCESS(Status))
{
goto ByeBye;
}
Status = VfatWriteFileData(IrpContext, Length, ByteOffset);
if (NT_SUCCESS(Status))
{
IrpContext->Irp->IoStatus.Information = Length;
}
}
if (!(IrpContext->Irp->Flags & IRP_PAGING_IO) &&
!(Fcb->Flags & (FCB_IS_FAT|FCB_IS_VOLUME)))
{
if(!(*Fcb->Attributes & FILE_ATTRIBUTE_DIRECTORY))
{
LARGE_INTEGER SystemTime;
// set dates and times
KeQuerySystemTime (&SystemTime);
if (Fcb->Flags & FCB_IS_FATX_ENTRY)
{
FsdSystemTimeToDosDateTime(IrpContext->DeviceExt,
&SystemTime, &Fcb->entry.FatX.UpdateDate,
&Fcb->entry.FatX.UpdateTime);
Fcb->entry.FatX.AccessDate = Fcb->entry.FatX.UpdateDate;
Fcb->entry.FatX.AccessTime = Fcb->entry.FatX.UpdateTime;
}
else
{
FsdSystemTimeToDosDateTime(IrpContext->DeviceExt,
&SystemTime, &Fcb->entry.Fat.UpdateDate,
&Fcb->entry.Fat.UpdateTime);
Fcb->entry.Fat.AccessDate = Fcb->entry.Fat.UpdateDate;
}
/* set date and times to dirty */
Fcb->Flags |= FCB_IS_DIRTY;
}
}
ByeBye:
if (Resource)
{
ExReleaseResourceLite(Resource);
}
if (Status == STATUS_PENDING)
{
Status = VfatLockUserBuffer(IrpContext->Irp, Length, IoReadAccess);
if (NT_SUCCESS(Status))
{
Status = VfatQueueRequest(IrpContext);
}
else
{
IrpContext->Irp->IoStatus.Status = Status;
IoCompleteRequest(IrpContext->Irp, IO_NO_INCREMENT);
VfatFreeIrpContext(IrpContext);
}
}
else
{
IrpContext->Irp->IoStatus.Status = Status;
if (IrpContext->FileObject->Flags & FO_SYNCHRONOUS_IO &&
!(IrpContext->Irp->Flags & IRP_PAGING_IO) && NT_SUCCESS(Status))
{
IrpContext->FileObject->CurrentByteOffset.QuadPart =
ByteOffset.QuadPart + IrpContext->Irp->IoStatus.Information;
}
IoCompleteRequest(IrpContext->Irp,
(CCHAR)(NT_SUCCESS(Status) ? IO_DISK_INCREMENT : IO_NO_INCREMENT));
VfatFreeIrpContext(IrpContext);
}
DPRINT("%x\n", Status);
return Status;
}
NTSTATUS
VfatRead(
PVFAT_IRP_CONTEXT IrpContext)
{
NTSTATUS Status;
PVFATFCB Fcb;
ULONG Length = 0;
ULONG ReturnedLength = 0;
PERESOURCE Resource = NULL;
LARGE_INTEGER ByteOffset;
PVOID Buffer;
ULONG BytesPerSector;
ASSERT(IrpContext);
DPRINT("VfatRead(IrpContext %p)\n", IrpContext);
ASSERT(IrpContext->DeviceObject);
// This request is not allowed on the main device object
if (IrpContext->DeviceObject == VfatGlobalData->DeviceObject)
{
DPRINT("VfatRead is called with the main device object.\n");
Status = STATUS_INVALID_DEVICE_REQUEST;
goto ByeBye;
}
ASSERT(IrpContext->DeviceExt);
ASSERT(IrpContext->FileObject);
Fcb = IrpContext->FileObject->FsContext;
ASSERT(Fcb);
if (Fcb->Flags & FCB_IS_PAGE_FILE)
{
PFATINFO FatInfo = &IrpContext->DeviceExt->FatInfo;
IrpContext->Stack->Parameters.Read.ByteOffset.QuadPart += FatInfo->dataStart * FatInfo->BytesPerSector;
IoSkipCurrentIrpStackLocation(IrpContext->Irp);
DPRINT("Read from page file, disk offset %I64x\n", IrpContext->Stack->Parameters.Read.ByteOffset.QuadPart);
Status = IoCallDriver(IrpContext->DeviceExt->StorageDevice, IrpContext->Irp);
VfatFreeIrpContext(IrpContext);
return Status;
}
DPRINT("<%wZ>\n", &Fcb->PathNameU);
ByteOffset = IrpContext->Stack->Parameters.Read.ByteOffset;
Length = IrpContext->Stack->Parameters.Read.Length;
BytesPerSector = IrpContext->DeviceExt->FatInfo.BytesPerSector;
/* fail if file is a directory and no paged read */
if (*Fcb->Attributes & FILE_ATTRIBUTE_DIRECTORY && !(IrpContext->Irp->Flags & IRP_PAGING_IO))
{
Status = STATUS_INVALID_PARAMETER;
goto ByeBye;
}
DPRINT("'%wZ', Offset: %u, Length %u\n", &Fcb->PathNameU, ByteOffset.u.LowPart, Length);
if (ByteOffset.u.HighPart && !(Fcb->Flags & FCB_IS_VOLUME))
{
Status = STATUS_INVALID_PARAMETER;
goto ByeBye;
}
if (ByteOffset.QuadPart >= Fcb->RFCB.FileSize.QuadPart)
{
IrpContext->Irp->IoStatus.Information = 0;
Status = STATUS_END_OF_FILE;
goto ByeBye;
}
if (IrpContext->Irp->Flags & (IRP_PAGING_IO | IRP_NOCACHE) || (Fcb->Flags & FCB_IS_VOLUME))
{
if (ByteOffset.u.LowPart % BytesPerSector != 0 || Length % BytesPerSector != 0)
{
DPRINT("%u %u\n", ByteOffset.u.LowPart, Length);
// non cached read must be sector aligned
Status = STATUS_INVALID_PARAMETER;
goto ByeBye;
}
}
if (Length == 0)
{
IrpContext->Irp->IoStatus.Information = 0;
Status = STATUS_SUCCESS;
goto ByeBye;
}
if (Fcb->Flags & FCB_IS_VOLUME)
{
Resource = &IrpContext->DeviceExt->DirResource;
}
else if (IrpContext->Irp->Flags & IRP_PAGING_IO)
{
Resource = &Fcb->PagingIoResource;
}
else
{
Resource = &Fcb->MainResource;
}
if (!ExAcquireResourceSharedLite(Resource,
IrpContext->Flags & IRPCONTEXT_CANWAIT ? TRUE : FALSE))
{
Resource = NULL;
Status = STATUS_PENDING;
goto ByeBye;
}
if (!(IrpContext->Irp->Flags & IRP_PAGING_IO) &&
FsRtlAreThereCurrentFileLocks(&Fcb->FileLock))
{
if (!FsRtlCheckLockForReadAccess(&Fcb->FileLock, IrpContext->Irp))
{
Status = STATUS_FILE_LOCK_CONFLICT;
goto ByeBye;
}
}
Buffer = VfatGetUserBuffer(IrpContext->Irp);
if (!Buffer)
{
Status = STATUS_INVALID_USER_BUFFER;
goto ByeBye;
}
if (!(IrpContext->Irp->Flags & (IRP_NOCACHE|IRP_PAGING_IO)) &&
!(Fcb->Flags & (FCB_IS_PAGE_FILE|FCB_IS_VOLUME)))
{
// cached read
Status = STATUS_SUCCESS;
if (ByteOffset.u.LowPart + Length > Fcb->RFCB.FileSize.u.LowPart)
{
Length = Fcb->RFCB.FileSize.u.LowPart - ByteOffset.u.LowPart;
Status = /*STATUS_END_OF_FILE*/STATUS_SUCCESS;
}
if (IrpContext->FileObject->PrivateCacheMap == NULL)
{
CcInitializeCacheMap(IrpContext->FileObject,
(PCC_FILE_SIZES)(&Fcb->RFCB.AllocationSize),
FALSE,
&(VfatGlobalData->CacheMgrCallbacks),
Fcb);
}
if (!CcCopyRead(IrpContext->FileObject, &ByteOffset, Length,
(BOOLEAN)(IrpContext->Flags & IRPCONTEXT_CANWAIT), Buffer,
&IrpContext->Irp->IoStatus))
{
Status = STATUS_PENDING;
goto ByeBye;
}
if (!NT_SUCCESS(IrpContext->Irp->IoStatus.Status))
{
Status = IrpContext->Irp->IoStatus.Status;
}
}
else
{
// non cached read
if (ByteOffset.QuadPart + Length > ROUND_UP(Fcb->RFCB.FileSize.QuadPart, BytesPerSector))
{
Length = (ULONG)(ROUND_UP(Fcb->RFCB.FileSize.QuadPart, BytesPerSector) - ByteOffset.QuadPart);
}
Status = VfatLockUserBuffer(IrpContext->Irp, Length, IoWriteAccess);
if (!NT_SUCCESS(Status))
{
goto ByeBye;
}
Status = VfatReadFileData(IrpContext, Length, ByteOffset, &ReturnedLength);
if (NT_SUCCESS(Status))
{
IrpContext->Irp->IoStatus.Information = ReturnedLength;
}
}
ByeBye:
if (Resource)
{
ExReleaseResourceLite(Resource);
}
if (Status == STATUS_PENDING)
{
Status = VfatLockUserBuffer(IrpContext->Irp, Length, IoWriteAccess);
if (NT_SUCCESS(Status))
{
Status = VfatQueueRequest(IrpContext);
}
else
{
IrpContext->Irp->IoStatus.Status = Status;
IoCompleteRequest(IrpContext->Irp, IO_NO_INCREMENT);
VfatFreeIrpContext(IrpContext);
}
}
else
{
IrpContext->Irp->IoStatus.Status = Status;
if (IrpContext->FileObject->Flags & FO_SYNCHRONOUS_IO &&
!(IrpContext->Irp->Flags & IRP_PAGING_IO) &&
(NT_SUCCESS(Status) || Status == STATUS_END_OF_FILE))
{
IrpContext->FileObject->CurrentByteOffset.QuadPart =
ByteOffset.QuadPart + IrpContext->Irp->IoStatus.Information;
}
IoCompleteRequest(IrpContext->Irp,
(CCHAR)(NT_SUCCESS(Status) ? IO_DISK_INCREMENT : IO_NO_INCREMENT));
VfatFreeIrpContext(IrpContext);
}
DPRINT("%x\n", Status);
return Status;
}
/*
* FUNCTION: Retrieve the specified volume information
*/
NTSTATUS
VfatQueryVolumeInformation(
PVFAT_IRP_CONTEXT IrpContext)
{
FS_INFORMATION_CLASS FsInformationClass;
NTSTATUS RC = STATUS_SUCCESS;
PVOID SystemBuffer;
ULONG BufferLength;
/* PRECONDITION */
ASSERT(IrpContext);
DPRINT("VfatQueryVolumeInformation(IrpContext %p)\n", IrpContext);
if (!ExAcquireResourceSharedLite(&((PDEVICE_EXTENSION)IrpContext->DeviceObject->DeviceExtension)->DirResource,
(BOOLEAN)(IrpContext->Flags & IRPCONTEXT_CANWAIT)))
{
return VfatQueueRequest(IrpContext);
}
/* INITIALIZATION */
FsInformationClass = IrpContext->Stack->Parameters.QueryVolume.FsInformationClass;
BufferLength = IrpContext->Stack->Parameters.QueryVolume.Length;
SystemBuffer = IrpContext->Irp->AssociatedIrp.SystemBuffer;
DPRINT("FsInformationClass %d\n", FsInformationClass);
DPRINT("SystemBuffer %p\n", SystemBuffer);
switch (FsInformationClass)
{
case FileFsVolumeInformation:
RC = FsdGetFsVolumeInformation(IrpContext->DeviceObject,
SystemBuffer,
&BufferLength);
break;
case FileFsAttributeInformation:
RC = FsdGetFsAttributeInformation(IrpContext->DeviceObject->DeviceExtension,
SystemBuffer,
&BufferLength);
break;
case FileFsSizeInformation:
RC = FsdGetFsSizeInformation(IrpContext->DeviceObject,
SystemBuffer,
&BufferLength);
break;
case FileFsDeviceInformation:
RC = FsdGetFsDeviceInformation(IrpContext->DeviceObject,
SystemBuffer,
&BufferLength);
break;
default:
RC = STATUS_NOT_SUPPORTED;
}
ExReleaseResourceLite(&((PDEVICE_EXTENSION)IrpContext->DeviceObject->DeviceExtension)->DirResource);
IrpContext->Irp->IoStatus.Status = RC;
if (NT_SUCCESS(RC))
IrpContext->Irp->IoStatus.Information =
IrpContext->Stack->Parameters.QueryVolume.Length - BufferLength;
else
IrpContext->Irp->IoStatus.Information = 0;
IoCompleteRequest(IrpContext->Irp, IO_NO_INCREMENT);
VfatFreeIrpContext(IrpContext);
return RC;
}
