write.c

FSD file system driver

						(bWait && bQueue),
						bAgain))
			{
				SetFlag(IrpContext->Flags, IRP_CONTEXT_FLAG_DEFERRED);

				CcDeferWrite(FileObject,
						(PCC_POST_DEFERRED_WRITE)FFSDeferWrite,
						IrpContext,
						Irp,
						Length,
						bAgain);

				bDeferred = TRUE;

				FFSBreakPoint();

				Status = STATUS_PENDING;
				__leave;
			}
		}

#endif

		if (IsEndOfFile(ByteOffset))
		{
			bAppendFile = TRUE;
			ByteOffset.QuadPart = Fcb->Header.FileSize.QuadPart;
		}

		if (FlagOn(Fcb->FFSMcb->FileAttr, FILE_ATTRIBUTE_DIRECTORY) && !PagingIo)
		{
			Status = STATUS_INVALID_DEVICE_REQUEST;
			__leave;
		}

		//
		//  Do flushing for such cases
		//
		if (Nocache && !PagingIo && (Fcb->SectionObject.DataSectionObject != NULL)) 
		{
			ExAcquireResourceExclusive(&Fcb->MainResource, 
					IsFlagOn(IrpContext->Flags, IRP_CONTEXT_FLAG_WAIT));

			MainResourceAcquired = TRUE;

			ExAcquireSharedStarveExclusive(&Fcb->PagingIoResource, TRUE);
			ExReleaseResource(&Fcb->PagingIoResource);

			CcFlushCache(&(Fcb->SectionObject),
					&ByteOffset,
					Length,
					&(Irp->IoStatus));
			ClearFlag(Fcb->Flags, FCB_FILE_MODIFIED);

			if (!NT_SUCCESS(Irp->IoStatus.Status)) 
			{
				Status = Irp->IoStatus.Status;
				__leave;
			}

			ExAcquireSharedStarveExclusive(&Fcb->PagingIoResource, TRUE);
			ExReleaseResource(&Fcb->PagingIoResource);

			CcPurgeCacheSection(&(Fcb->SectionObject),
					(PLARGE_INTEGER)&(ByteOffset),
					Length,
					FALSE);

			ExReleaseResource(&Fcb->MainResource);
			MainResourceAcquired = FALSE;
		}

		if (!PagingIo)
		{
			if (!ExAcquireResourceExclusiveLite(
						&Fcb->MainResource,
						IrpContext->IsSynchronous))
			{
				Status = STATUS_PENDING;
				__leave;
			}

			MainResourceAcquired = TRUE;
		}
		else
		{
			/*
			ULONG ResShCnt, ResExCnt; 
			ResShCnt = ExIsResourceAcquiredSharedLite(&Fcb->PagingIoResource);
			ResExCnt = ExIsResourceAcquiredExclusiveLite(&Fcb->PagingIoResource);

			FFSPrint((DBG_USER, "FFSWriteFile: Inode=%xh %S PagingIo: %xh:%xh Synchronous=%xh\n",
			Fcb->FFSMcb->Inode, Fcb->FFSMcb->ShortName.Buffer, ResShCnt, ResExCnt, IrpContext->IsSynchronous));
			*/
			if (!ExAcquireResourceSharedLite(
						&Fcb->PagingIoResource,
						IrpContext->IsSynchronous))
			{
				Status = STATUS_PENDING;
				__leave;
			}

			PagingIoResourceAcquired = TRUE;
		}

		if (!PagingIo)
		{
			if (!FsRtlCheckLockForWriteAccess(
						&Fcb->FileLockAnchor,
						Irp))
			{
				Status = STATUS_FILE_LOCK_CONFLICT;
				__leave;
			}
		}

		if (Nocache)
		{
			if ((ByteOffset.QuadPart + Length) >
					Fcb->Header.AllocationSize.QuadPart)
			{
				if (ByteOffset.QuadPart >= 
						Fcb->Header.AllocationSize.QuadPart)
				{
					Status = STATUS_SUCCESS;
					Irp->IoStatus.Information = 0;
					__leave;
				}
				else
				{
					if (Length > (ULONG)(Fcb->Header.AllocationSize.QuadPart
								- ByteOffset.QuadPart))
					{
						Length = (ULONG)(Fcb->Header.AllocationSize.QuadPart
								- ByteOffset.QuadPart);
					}
				}
			}
		}

		if (!Nocache)
		{
			if (FlagOn(Fcb->FFSMcb->FileAttr, FILE_ATTRIBUTE_DIRECTORY))
			{
				__leave;
			}

			if (FileObject->PrivateCacheMap == NULL)
			{
				CcInitializeCacheMap(
						FileObject,
						(PCC_FILE_SIZES)(&Fcb->Header.AllocationSize),
						FALSE,
						&FFSGlobal->CacheManagerCallbacks,
						Fcb);

				CcSetReadAheadGranularity(
						FileObject,
						READ_AHEAD_GRANULARITY);

				CcSetFileSizes(
						FileObject, 
						(PCC_FILE_SIZES)(&(Fcb->Header.AllocationSize)));
			}

			CacheObject = FileObject;

			//
			//  Need extending the size of inode ?
			//
			if ((bAppendFile) || ((ULONG)(ByteOffset.QuadPart + Length) >
						(ULONG)(Fcb->Header.FileSize.QuadPart)))
			{

				LARGE_INTEGER   ExtendSize;
				LARGE_INTEGER   FileSize;

				bNeedExtending = TRUE;
				FileSize = Fcb->Header.FileSize;
				ExtendSize.QuadPart = (LONGLONG)(ByteOffset.QuadPart + Length);

				if (ExtendSize.QuadPart > Fcb->Header.AllocationSize.QuadPart)
				{
					if (!FFSExpandFile(IrpContext, Vcb, Fcb, &ExtendSize))
					{
						Status = STATUS_INSUFFICIENT_RESOURCES;
						__leave;
					}
				}

				{
					Fcb->Header.FileSize.QuadPart = ExtendSize.QuadPart;
					Fcb->dinode1->di_size = (ULONG)ExtendSize.QuadPart;
				}

				if (FileObject->PrivateCacheMap)
				{
					CcSetFileSizes(FileObject, (PCC_FILE_SIZES)(&(Fcb->Header.AllocationSize)));

					if (ByteOffset.QuadPart > FileSize.QuadPart)
					{
						FFSZeroHoles(IrpContext, Vcb, FileObject, FileSize.QuadPart, 
								ByteOffset.QuadPart - FileSize.QuadPart);
					}

					if (Fcb->Header.AllocationSize.QuadPart > ExtendSize.QuadPart)
					{
						FFSZeroHoles(IrpContext, Vcb, FileObject, ExtendSize.QuadPart, 
								Fcb->Header.AllocationSize.QuadPart - ExtendSize.QuadPart);
					}
				}

				if (FFSv1SaveInode(IrpContext, Vcb, Fcb->FFSMcb->Inode, Fcb->dinode1))
				{
					Status = STATUS_SUCCESS;
				}

				FFSNotifyReportChange(
						IrpContext,
						Vcb,
						Fcb,
						FILE_NOTIFY_CHANGE_SIZE,
						FILE_ACTION_MODIFIED);
			}

			if (FlagOn(IrpContext->MinorFunction, IRP_MN_MDL))
			{
				CcPrepareMdlWrite(
						CacheObject,
						(&ByteOffset),
						Length,
						&Irp->MdlAddress,
						&Irp->IoStatus);

				Status = Irp->IoStatus.Status;
			}
			else
			{
				Buffer = FFSGetUserBuffer(Irp);

				if (Buffer == NULL)
				{
					FFSBreakPoint();
					Status = STATUS_INVALID_USER_BUFFER;
					__leave;
				}

				if (!CcCopyWrite(
							CacheObject,
							(PLARGE_INTEGER)&ByteOffset,
							Length,
							IrpContext->IsSynchronous,
							Buffer))
				{
					Status = STATUS_PENDING;
					__leave;
				}

				Status = Irp->IoStatus.Status;
			}

			if (NT_SUCCESS(Status))
			{
				Irp->IoStatus.Information = Length;

				if (IsFlagOn(Vcb->Flags, VCB_FLOPPY_DISK))
				{
					FFSPrint((DBG_USER, "FFSWriteFile is starting FlushingDpc...\n"));
					FFSStartFloppyFlushDpc(Vcb, Fcb, FileObject);
				}
			}
		}
		else
		{
			ReturnedLength = Length;

			Status = FFSLockUserBuffer(
					IrpContext->Irp,
					Length,
					IoReadAccess);

			if (!NT_SUCCESS(Status))
			{
				__leave;
			}

			Irp->IoStatus.Status = STATUS_SUCCESS;
			Irp->IoStatus.Information = Length;

			Status = 
				FFSv1WriteInode(
						IrpContext,
						Vcb,
						Fcb->dinode1,
						(ULONGLONG)(ByteOffset.QuadPart),
						NULL,
						Length,
						TRUE,
						&ReturnedLength);

			Irp = IrpContext->Irp;

		}
	}

	__finally
	{
		if (PagingIoResourceAcquired)
		{
			ExReleaseResourceForThreadLite(
					&Fcb->PagingIoResource,
					ExGetCurrentResourceThread());
		}

		if (MainResourceAcquired)
		{
			ExReleaseResourceForThreadLite(
					&Fcb->MainResource,
					ExGetCurrentResourceThread());
		}

		if (!IrpContext->ExceptionInProgress)
		{
			if (Irp)
			{
				if (Status == STATUS_PENDING)
				{
					if (!bDeferred)
					{
						Status = FFSLockUserBuffer(
									IrpContext->Irp,
									Length,
									IoReadAccess);

						if (NT_SUCCESS(Status))
						{
							Status = FFSQueueRequest(IrpContext);
						}
						else
						{
							FFSCompleteIrpContext(IrpContext, Status);
						}
					}
				}
				else
				{
					if (NT_SUCCESS(Status))
					{
						if (SynchronousIo && !PagingIo)
						{
							FileObject->CurrentByteOffset.QuadPart =
								ByteOffset.QuadPart + Irp->IoStatus.Information;
						}

						if (!PagingIo)
						{
							SetFlag(FileObject->Flags, FO_FILE_MODIFIED);
							SetFlag(Fcb->Flags, FCB_FILE_MODIFIED);
						}
					}

					FFSCompleteIrpContext(IrpContext, Status);
				}
			}
			else
			{
				FFSFreeIrpContext(IrpContext);
			}
		}
	}

	return Status;

}


NTSTATUS
FFSWriteComplete(
	IN PFFS_IRP_CONTEXT IrpContext)
{
	NTSTATUS        Status = STATUS_UNSUCCESSFUL;
	PFILE_OBJECT    FileObject;
	PIRP            Irp;
	PIO_STACK_LOCATION IrpSp;

	__try
	{
		ASSERT(IrpContext);

		ASSERT((IrpContext->Identifier.Type == FFSICX) &&
				(IrpContext->Identifier.Size == sizeof(FFS_IRP_CONTEXT)));

		FileObject = IrpContext->FileObject;

		Irp = IrpContext->Irp;
		IrpSp = IoGetCurrentIrpStackLocation(Irp);

		CcMdlWriteComplete(FileObject, &(IrpSp->Parameters.Write.ByteOffset), Irp->MdlAddress);

		Irp->MdlAddress = NULL;

		Status = STATUS_SUCCESS;
	}

	__finally
	{
		if (!IrpContext->ExceptionInProgress)
		{
			FFSCompleteIrpContext(IrpContext, Status);
		}
	}

	return Status;
}


NTSTATUS
FFSWrite(
	IN PFFS_IRP_CONTEXT IrpContext)
{
	NTSTATUS            Status;
	PFFS_FCBVCB         FcbOrVcb;
	PDEVICE_OBJECT      DeviceObject;
	PFILE_OBJECT        FileObject;
	PFFS_VCB            Vcb;
	BOOLEAN             bCompleteRequest = TRUE;

	ASSERT(IrpContext);

	ASSERT((IrpContext->Identifier.Type == FFSICX) &&
			(IrpContext->Identifier.Size == sizeof(FFS_IRP_CONTEXT)));

	__try
	{
		if (FlagOn(IrpContext->MinorFunction, IRP_MN_COMPLETE))
		{
			Status = FFSWriteComplete(IrpContext);
			bCompleteRequest = FALSE;
		}
		else
		{
			DeviceObject = IrpContext->DeviceObject;

			if (DeviceObject == FFSGlobal->DeviceObject)
			{
				Status = STATUS_INVALID_DEVICE_REQUEST;
				__leave;
			}

			Vcb = (PFFS_VCB)DeviceObject->DeviceExtension;

			if (Vcb->Identifier.Type != FFSVCB ||
					Vcb->Identifier.Size != sizeof(FFS_VCB))
			{
				Status = STATUS_INVALID_PARAMETER;
				__leave;
			}

			ASSERT(IsMounted(Vcb));

			if (IsFlagOn(Vcb->Flags, VCB_DISMOUNT_PENDING))
			{
				Status = STATUS_TOO_LATE;
				__leave;
			}

			if (IsFlagOn(Vcb->Flags, VCB_READ_ONLY))
			{
				Status = STATUS_MEDIA_WRITE_PROTECTED;
				__leave;
			}

			FileObject = IrpContext->FileObject;

			FcbOrVcb = (PFFS_FCBVCB)FileObject->FsContext;

			if (FcbOrVcb->Identifier.Type == FFSVCB)
			{
				Status = FFSWriteVolume(IrpContext);

				if (!NT_SUCCESS(Status))
				{
					FFSBreakPoint();
				}

				bCompleteRequest = FALSE;
			}
			else if (FcbOrVcb->Identifier.Type == FFSFCB)
			{
				Status = FFSWriteFile(IrpContext);

				if (!NT_SUCCESS(Status))
				{
					FFSBreakPoint();
				}

				bCompleteRequest = FALSE;
			}
			else
			{
				Status = STATUS_INVALID_PARAMETER;
			}
		}
	}

	__finally
	{
		if (bCompleteRequest)
		{
			FFSCompleteIrpContext(IrpContext, Status);
		}
	}

	return Status;
}