From b4e21f0b6f78248963bd8dd17265b240af6ea2d6 Mon Sep 17 00:00:00 2001
From: Pierre Schweitzer <pierre@reactos.org>
Date: Fri, 1 May 2015 17:45:16 +0000
Subject: [PATCH] [CDFS] No, FastIo is not possible!

svn path=/trunk/; revision=67500
---
 reactos/drivers/filesystems/cdfs/cdfs.c | 25 +++++++++++++++++++++++++
 reactos/drivers/filesystems/cdfs/cdfs.h |  1 +
 2 files changed, 26 insertions(+)

diff --git a/reactos/drivers/filesystems/cdfs/cdfs.c b/reactos/drivers/filesystems/cdfs/cdfs.c
index 77dc734f9e8..9aa1412981f 100644
--- a/reactos/drivers/filesystems/cdfs/cdfs.c
+++ b/reactos/drivers/filesystems/cdfs/cdfs.c
@@ -100,6 +100,7 @@ DriverEntry(PDRIVER_OBJECT DriverObject,
         CdfsDeviceControl;
 
     CdfsGlobalData->FastIoDispatch.SizeOfFastIoDispatch = sizeof(FAST_IO_DISPATCH);
+    CdfsGlobalData->FastIoDispatch.FastIoCheckIfPossible = CdfsFastIoCheckIfPossible;
     CdfsGlobalData->FastIoDispatch.FastIoRead = CdfsFastIoRead;
     CdfsGlobalData->FastIoDispatch.FastIoWrite = CdfsFastIoWrite;
     DriverObject->FastIoDispatch = &CdfsGlobalData->FastIoDispatch;
@@ -147,6 +148,30 @@ CdfsReleaseFromLazyWrite(IN PVOID Context)
     ExReleaseResourceLite(&(Fcb->MainResource));
 }
 
+BOOLEAN
+NTAPI
+CdfsFastIoCheckIfPossible(
+    _In_ PFILE_OBJECT FileObject,
+    _In_ PLARGE_INTEGER FileOffset,
+    _In_ ULONG Length,
+    _In_ BOOLEAN Wait,
+    _In_ ULONG LockKey,
+    _In_ BOOLEAN CheckForReadOperation,
+    _Out_ PIO_STATUS_BLOCK IoStatus,
+    _In_ PDEVICE_OBJECT DeviceObject)
+{
+    /* Deny FastIo */
+    UNREFERENCED_PARAMETER(FileObject);
+    UNREFERENCED_PARAMETER(FileOffset);
+    UNREFERENCED_PARAMETER(Length);
+    UNREFERENCED_PARAMETER(Wait);
+    UNREFERENCED_PARAMETER(LockKey);
+    UNREFERENCED_PARAMETER(CheckForReadOperation);
+    UNREFERENCED_PARAMETER(IoStatus);
+    UNREFERENCED_PARAMETER(DeviceObject);
+    return FALSE;
+}
+
 BOOLEAN
 NTAPI
 CdfsFastIoRead(
diff --git a/reactos/drivers/filesystems/cdfs/cdfs.h b/reactos/drivers/filesystems/cdfs/cdfs.h
index 67ce0f34369..5ece03ab90d 100644
--- a/reactos/drivers/filesystems/cdfs/cdfs.h
+++ b/reactos/drivers/filesystems/cdfs/cdfs.h
@@ -481,6 +481,7 @@ CdfsAcquireForLazyWrite(IN PVOID Context,
 VOID NTAPI
 CdfsReleaseFromLazyWrite(IN PVOID Context);
 
+FAST_IO_CHECK_IF_POSSIBLE CdfsFastIoCheckIfPossible;
 FAST_IO_READ CdfsFastIoRead;
 FAST_IO_WRITE CdfsFastIoWrite;