https://git.reactos.org/?p=reactos.git;a=commitdiff;h=da5dcdcbf285fe7c6acad9623fec3732e216d719
commit da5dcdcbf285fe7c6acad9623fec3732e216d719 Author: Hermès Bélusca-Maïto <[email protected]> AuthorDate: Sun Apr 22 22:13:52 2018 +0200 Commit: Hermès Bélusca-Maïto <[email protected]> CommitDate: Sun Apr 22 22:23:54 2018 +0200 [NULL] Additions for the Null driver. - Allow the driver to be unloaded, as on Windows. - Use a static fast IO dispatch table, instead of allocating one and risking any potential memory allocation failure. - Update the file header. --- drivers/base/null/null.c | 64 +++++++++++++++++++++++++++--------------------- 1 file changed, 36 insertions(+), 28 deletions(-) diff --git a/drivers/base/null/null.c b/drivers/base/null/null.c index 610e886ddd..0d4ed541de 100644 --- a/drivers/base/null/null.c +++ b/drivers/base/null/null.c @@ -1,16 +1,19 @@ /* - * PROJECT: ReactOS Kernel - * LICENSE: GPL - See COPYING in the top level directory - * FILE: drivers/base/null/null.c - * PURPOSE: Null Device Driver - * PROGRAMMERS: Alex Ionescu ([email protected]) - * David Welch ([email protected]) + * PROJECT: ReactOS Kernel + * LICENSE: GPL-2.0+ (https://spdx.org/licenses/GPL-2.0+) + * PURPOSE: Null Device Driver + * COPYRIGHT: Copyright 1998-2018 David Welch ([email protected]) + * Copyright 2007-2018 Alex Ionescu ([email protected]) */ /* INCLUDES ******************************************************************/ #include <wdm.h> +/* GLOBALS *******************************************************************/ + +FAST_IO_DISPATCH FastIoDispatch; + /* FUNCTIONS *****************************************************************/ NTSTATUS @@ -20,6 +23,7 @@ NullQueryFileInformation(OUT PVOID Buffer, IN FILE_INFORMATION_CLASS InformationClass) { PFILE_STANDARD_INFORMATION StandardInfo = Buffer; + PAGED_CODE(); /* We only support one class */ @@ -81,10 +85,11 @@ NTAPI NullDispatch(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp) { - PIO_STACK_LOCATION IoStack = IoGetCurrentIrpStackLocation(Irp); NTSTATUS Status; + PIO_STACK_LOCATION IoStack = IoGetCurrentIrpStackLocation(Irp); PFILE_OBJECT FileObject; ULONG Length; + PAGED_CODE(); /* Get the file object and check what kind of request this is */ @@ -150,21 +155,33 @@ NullDispatch(IN PDEVICE_OBJECT DeviceObject, return Status; } +VOID +NTAPI +NullUnload(IN PDRIVER_OBJECT DriverObject) +{ + PDEVICE_OBJECT DeviceObject = DriverObject->DeviceObject; + + /* Delete the Null device */ + IoDeleteDevice(DeviceObject); +} + NTSTATUS NTAPI DriverEntry(IN PDRIVER_OBJECT DriverObject, IN PUNICODE_STRING RegistryPath) { + NTSTATUS Status; PDEVICE_OBJECT DeviceObject; UNICODE_STRING DeviceName = RTL_CONSTANT_STRING(L"\\Device\\Null"); - NTSTATUS Status; - PFAST_IO_DISPATCH FastIoDispatch; + PAGED_CODE(); + UNREFERENCED_PARAMETER(RegistryPath); + /* Page the driver */ MmPageEntireDriver(DriverEntry); - /* Create null device */ + /* Create the Null device */ Status = IoCreateDevice(DriverObject, 0, &DeviceName, @@ -172,7 +189,8 @@ DriverEntry(IN PDRIVER_OBJECT DriverObject, 0, FALSE, &DeviceObject); - if (!NT_SUCCESS(Status)) return Status; + if (!NT_SUCCESS(Status)) + return Status; /* Register driver routines */ DriverObject->MajorFunction[IRP_MJ_CLOSE] = NullDispatch; @@ -181,26 +199,16 @@ DriverEntry(IN PDRIVER_OBJECT DriverObject, DriverObject->MajorFunction[IRP_MJ_READ] = NullDispatch; DriverObject->MajorFunction[IRP_MJ_LOCK_CONTROL] = NullDispatch; DriverObject->MajorFunction[IRP_MJ_QUERY_INFORMATION] = NullDispatch; + DriverObject->DriverUnload = NullUnload; - /* Allocate the fast I/O dispatch table */ - FastIoDispatch = ExAllocatePoolWithTag(NonPagedPool, - sizeof(FAST_IO_DISPATCH), - 'llun'); - if (!FastIoDispatch) - { - /* Failed, cleanup */ - IoDeleteDevice(DeviceObject); - return STATUS_INSUFFICIENT_RESOURCES; - } - - /* Initialize it */ - RtlZeroMemory(FastIoDispatch, sizeof(FAST_IO_DISPATCH)); - FastIoDispatch->SizeOfFastIoDispatch = sizeof(FAST_IO_DISPATCH); + /* Initialize the fast I/O dispatch table */ + RtlZeroMemory(&FastIoDispatch, sizeof(FastIoDispatch)); + FastIoDispatch.SizeOfFastIoDispatch = sizeof(FastIoDispatch); /* Setup our pointers */ - FastIoDispatch->FastIoRead = NullRead; - FastIoDispatch->FastIoWrite = NullWrite; - DriverObject->FastIoDispatch = FastIoDispatch; + FastIoDispatch.FastIoRead = NullRead; + FastIoDispatch.FastIoWrite = NullWrite; + DriverObject->FastIoDispatch = &FastIoDispatch; /* Return success */ return STATUS_SUCCESS;
