diff -r 000000000000 -r a41df078684a userlibandfileserver/fileserver/smassstorage/rwdrivethread.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/userlibandfileserver/fileserver/smassstorage/rwdrivethread.cpp	Mon Oct 19 15:55:17 2009 +0100
@@ -0,0 +1,583 @@
+// Copyright (c) 2007-2009 Nokia Corporation and/or its subsidiary(-ies).
+// All rights reserved.
+// This component and the accompanying materials are made available
+// under the terms of the License "Eclipse Public License v1.0"
+// which accompanies this distribution, and is available
+// at the URL "http://www.eclipse.org/legal/epl-v10.html".
+//
+// Initial Contributors:
+// Nokia Corporation - initial contribution.
+//
+// Contributors:
+//
+// Description:
+//
+
+#include "scsiprot.h"
+#include "usbmsshared.h"
+#include "rwdrivethread.h"
+#include "massstoragedebug.h"
+
+// ---
+
+#ifdef PRINT_MSDC_MULTITHREADED_READ_INFO
+#define __MT_READ_PRINT(t) {RDebug::Print(t);}
+#define __MT_READ_PRINT1(t,a) {RDebug::Print(t,a);}
+#define __MT_READ_PRINT2(t,a,b) {RDebug::Print(t,a,b);}
+#else
+#define __MT_READ_PRINT(t)
+#define __MT_READ_PRINT1(t,a)
+#define __MT_READ_PRINT2(t,a,b)
+#endif // PRINT_MSDC_MULTITHREADED_READ_INFO
+
+
+#ifdef MSDC_MULTITHREADED 
+
+TBlockDesc::TBlockDesc()
+	:iBuf((TUint8 *)NULL,0,0)
+	{
+	}
+
+void TBlockDesc::SetPtr(TPtr8& aDes)
+	{
+	iBuf.Set(aDes);
+	}
+
+
+TBlockDescBuffer::TBlockDescBuffer()
+	{ 
+	iDescReadPtr = &iDesc1;
+	iDescWritePtr = &iDesc2;
+	}
+
+void TBlockDescBuffer::SetUpReadBuf(TPtr8& aDes1, TPtr8& aDes2)
+	{
+	iDesc1.SetPtr(aDes1);
+	iDesc2.SetPtr(aDes2);
+	iDescReadPtr = &iDesc1;
+	iDescWritePtr = &iDesc2;
+	}
+
+
+//-----------------------------------------------
+
+/**
+Construct a CThreadContext object.
+
+@param aName The name to be assigned to this thread.
+@param aThreadFunction Function to be called when thread is initially scheduled.
+@param aOwner Pointer to the object owning the thread. Used as the parameter to aThreadFunction.
+*/
+CThreadContext* CThreadContext::NewL(const TDesC& aName,
+									 TThreadFunction aThreadFunction,
+									 TAny* aOwner)
+	{
+	__FNLOG("CThreadContext::NewL");
+	CThreadContext* self = new (ELeave) CThreadContext();
+	CleanupStack::PushL(self);
+	self->ConstructL(aName, aThreadFunction, aOwner);
+	CleanupStack::Pop();
+	return self;
+	}
+
+/**
+Construct a CThreadContext object
+
+@param aName The name to be assigned to this thread.
+@param aThreadFunction Function to be called when thread is initially scheduled.
+@param aOwner Pointer to the object owning the thread. Used as the parameter to aThreadFunction.
+*/
+void CThreadContext::ConstructL(const TDesC& aName,
+								TThreadFunction aThreadFunction,
+								TAny* aOwner)
+	{
+	__FNLOG("CThreadContext::ConstructL");
+	__PRINT(_L("Creating Critical Section"));
+	User::LeaveIfError(iCritSect.CreateLocal());
+	__PRINT(_L("Creating RThread"));
+
+	TUint serial(0); // Used to retry creation of a thread in case
+					 // one with the same name already exists
+
+	RBuf threadName;
+	threadName.CreateMaxL(aName.Length() + 8);
+	CleanupClosePushL(threadName);
+	threadName = aName;
+
+	TInt err;
+	for (;;)
+		{
+		err = iThread.Create(threadName, aThreadFunction, 0x1000, NULL, aOwner);
+		__PRINT2(_L("CThreadContext::ConstructL Created thread %S err=%d"), &threadName, err);
+
+        // for a restart wait and retry until old thread is gone
+		if (err == KErrAlreadyExists)
+			{
+			User::After(10 * 1000);     // 10 mS
+			threadName = aName;
+			threadName.AppendNumFixedWidth(serial, EDecimal, 8);
+			++serial;
+			}
+		else
+			{
+			break;
+			}
+		}
+
+    User::LeaveIfError(err);
+    CleanupStack::Pop(); // threadName
+    threadName.Close();
+
+	// set priority
+	iThread.SetPriority(EPriorityMore);
+	}
+
+
+/**
+Construct a CThreadContext object
+*/
+CThreadContext::CThreadContext()
+	:
+	iError(KErrNone)
+	{
+	__FNLOG("CThreadContext::CThreadContext");
+	}
+
+/**
+Destructor
+*/
+CThreadContext::~CThreadContext()
+	{
+	__FNLOG("CThreadContext::~CThreadContext");
+	__PRINT(_L("Closing Critical Section"));
+	iCritSect.Close();
+	__PRINT(_L("Killing ThreadContext"));
+	iThread.Kill(0);
+	__PRINT(_L("Closing ThreadContext"));
+	iThread.Close();
+	}
+
+//-----------------------------------------------
+
+/**
+Construct a CWriteDriveThread object
+*/
+CWriteDriveThread* CWriteDriveThread::NewL()
+	{
+	__FNLOG("CWriteDriveThread::NewL");
+	CWriteDriveThread* self = new (ELeave) CWriteDriveThread();
+	CleanupStack::PushL(self);
+	self->ConstructL();
+	CleanupStack::Pop();
+	return self;
+	}
+
+/**
+Construct a CWriteDriveThread object
+*/
+void CWriteDriveThread::ConstructL()
+	{
+	__FNLOG("CWriteDriveThread::ConstructL");
+	TBuf<16> name = _L("MassStorageWrite");
+	iThreadContext = CThreadContext::NewL(name, ThreadFunction, this);
+	// There are two free pointers to start with so initialise the semaphore with 1
+	User::LeaveIfError(iProducerSem.CreateLocal(1));
+	User::LeaveIfError(iConsumerSem.CreateLocal(0));
+	
+	iThreadContext->Resume();
+	}
+
+/**
+Construct a CWriteDriveThread object
+*/
+CWriteDriveThread::CWriteDriveThread() 
+	: iIsCommandWrite10(EFalse)
+	{
+	__FNLOG("CWriteDriveThread::CWriteDriveThread");
+	}
+
+/**
+Destructor
+*/
+CWriteDriveThread::~CWriteDriveThread()
+	{
+	__FNLOG("CWriteDriveThread::~CWriteDriveThread");
+	delete iThreadContext;
+	}
+
+/**
+This function is called when the thread is initially scheduled.
+
+@param aSelf Pointer to self to facilitate call to member method.
+*/
+TInt CWriteDriveThread::ThreadFunction(TAny* aSelf)
+	{
+	__FNLOG("CWriteDriveThread::ThreadFunction");
+	CWriteDriveThread* self = static_cast<CWriteDriveThread*>(aSelf);
+	return self->WriteToDrive();
+	}
+
+/**
+Writes the data pointed to by iDescWritePtr to the drive.
+*/
+TInt CWriteDriveThread::WriteToDrive()
+	{
+	__FNLOG("\tCWriteDriveThread::WriteToDrive");
+
+	// One-off convenience variable assignment
+	TBlockDesc* &desc = iThreadContext->iBuffer.iDescWritePtr;
+	
+	for(;;)
+		{
+		iConsumerSem.Wait();
+		__PRINT(_L("\tWaiting on Write CS..."));
+		iThreadContext->iCritSect.Wait();
+		// +++ WRITE CS STARTS HERE +++
+		__PRINT1(_L("\tNow using as write buffer: iBuf%d"), iThreadContext->iBuffer.GetBufferNumber(&desc->iBuf));
+#ifdef MEASURE_AND_DISPLAY_WRITE_TIME
+		RDebug::Print(_L("\tSCSI: writing %d bytes\n"), desc->iBuf.Length());
+		TTime t0, t1;
+		t0.HomeTime();
+#else
+		__PRINT1(_L("\tSCSI: writing %d bytes\n"), desc->iBuf.Length());
+#endif
+		// Write buffer to disk
+
+#ifdef INJECT_ERROR
+		if (desc->iBuf[0] == '2')
+		{
+			desc->iBuf[0] = 'x';
+			RDebug::Printf("Injecting error");
+		}
+
+		
+		RDebug::Printf("%08lx %x [%x] [%x]", desc->iByteOffset, desc->iBuf.Length(), 
+			desc->iBuf[0],
+			desc->iBuf[desc->iBuf.Length()-1]);
+#endif
+
+		iThreadContext->iError = iThreadContext->iDrive->Write(desc->iByteOffset, desc->iBuf,iThreadContext->iDrive->IsWholeMediaAccess());
+#ifdef INJECT_ERROR
+		if (desc->iBuf[0] == 'x')
+		{
+			iThreadContext->iError = KErrUnknown;
+		}
+#endif
+
+#ifdef MEASURE_AND_DISPLAY_WRITE_TIME
+		t1.HomeTime();
+		const TTimeIntervalMicroSeconds time = t1.MicroSecondsFrom(t0);
+		const TUint time_ms = I64LOW(time.Int64() / 1000);
+		RDebug::Print(_L("SCSI: write took %d ms\n"), time_ms);
+#endif
+		iCallback((TUint8*) (desc->iBuf.Ptr()), iCallbackParameter);
+		iWriteCounter--;
+		ASSERT(iWriteCounter >= 0);
+
+		__PRINT(_L("\tSignalling Write CS"));
+		iThreadContext->iCritSect.Signal();
+		// +++ WRITE CS ENDS HERE +++
+		iProducerSem.Signal();
+		}
+	}
+
+/**
+Initiates writing data pointed to by iReadBuf to the drive and resumes the thread. Writing 
+is completed by the ThreadFunction when the thread is resumed.
+
+@param aDrive Drive to write to.
+@param aOffset Write offset.
+*/
+TInt CWriteDriveThread::WriteDriveData(CMassStorageDrive* aDrive, const TInt64& aOffset, TPtrC8& aDes, ProcessWriteCompleteFunc aFunc, TAny* aPtr)
+	{
+	// Check error code from previous write
+	const TInt r = iThreadContext->iError;
+	if (r != KErrNone)
+		{
+		__PRINT1(_L("Error after previous write = 0x%x \n"), r);
+		return KErrAbort;
+        }
+
+	// Swap the two buffer pointers
+	iProducerSem.Wait();
+	__PRINT(_L("Waiting on Write CS..."));
+	// +++ WRITE CS STARTS HERE +++
+	iThreadContext->iCritSect.Wait();
+
+	// New DB First read into the iDescReadPtr pointer,
+	// then swap,so that write pointer points to correct location, as the ptr pointed to by iDescWritePtr is what is written from in WriteToDrive 
+	iThreadContext->iBuffer.iDescReadPtr->iBuf.Set((TUint8*)aDes.Ptr(), aDes.Length(), KMaxBufSize );
+	
+	iCallback = aFunc;
+	iCallbackParameter = aPtr;
+
+	iWriteCounter++;
+	iThreadContext->iBuffer.SwapDesc();
+	// Prepare variables for next write
+	iThreadContext->iDrive = aDrive;
+	iThreadContext->iBuffer.iDescWritePtr->iByteOffset = aOffset;
+	// +++ WRITE CS ENDS HERE +++
+	__PRINT(_L("Signalling Write CS..."));
+	iThreadContext->iCritSect.Signal();
+
+	iConsumerSem.Signal();
+	return KErrNone;
+}
+
+
+void CWriteDriveThread::WaitForWriteEmpty()
+{
+	while(iWriteCounter > 0)
+		{
+		User::After(100);
+		}
+}
+
+// Check if the target address range was recently written to, this is to force a
+// cache miss when reading from the same sectors that were just written. 
+// Optimisation note: this is only needed if the read precache was started
+// before the write was completed.
+TBool CWriteDriveThread::IsRecentlyWritten(TInt64 aOffset, TInt aLength)
+{
+	ASSERT(iWriteCounter == 0);
+	if (iIsCommandWrite10) //If the previous command is Write10, then discard pre-read as the same buffers are used and will be over written by Write10 
+		return ETrue;
+	if(aOffset <= iThreadContext->iBuffer.iDescReadPtr->iByteOffset &&
+			aOffset + aLength >= iThreadContext->iBuffer.iDescReadPtr->iByteOffset)
+		return ETrue;
+	if(aOffset >= iThreadContext->iBuffer.iDescReadPtr->iByteOffset &&
+			aOffset <= iThreadContext->iBuffer.iDescReadPtr->iByteOffset + iThreadContext->iBuffer.iDescReadPtr->iLength)
+		return ETrue;
+	if(aOffset <= iThreadContext->iBuffer.iDescWritePtr->iByteOffset &&
+			aOffset + aLength >= iThreadContext->iBuffer.iDescReadPtr->iByteOffset)
+		return ETrue;
+	if(aOffset >= iThreadContext->iBuffer.iDescWritePtr->iByteOffset &&
+			aOffset <= iThreadContext->iBuffer.iDescReadPtr->iByteOffset + iThreadContext->iBuffer.iDescReadPtr->iLength)
+		return ETrue;
+	return EFalse;
+}
+
+//-----------------------------------------------
+
+/**
+Construct a CReadDriveThread object
+*/
+CReadDriveThread* CReadDriveThread::NewL()
+	{
+	__FNLOG("CReadDriveThread::NewL");
+	CReadDriveThread* self = new (ELeave) CReadDriveThread();
+	CleanupStack::PushL(self);
+	self->ConstructL();
+	CleanupStack::Pop();
+	return self;
+	}
+
+/**
+Construct a CReadDriveThread object
+
+@param aName The name to be assigned to this thread.
+@pram aThreadFunction Function to be called when thread is initially scheduled.
+*/
+void CReadDriveThread::ConstructL()
+	{
+	__FNLOG("CReadDriveThread::ConstructL");
+	TBuf<15> name = _L("MassStorageRead");
+	iThreadContext = CThreadContext::NewL(name, ThreadFunction, this);
+	}
+
+/**
+Construct a CReadDriveThread object
+*/
+CReadDriveThread::CReadDriveThread()
+	:
+	iThreadRunning(EFalse)
+	{
+	__FNLOG("CReadDriveThread::CReadDriveThread");
+	}
+
+/**
+Destructor
+*/
+CReadDriveThread::~CReadDriveThread()
+	{
+	__FNLOG("CReadDriveThread::~CReadDriveThread");
+	delete iThreadContext;
+	}
+
+/**
+This function is called when the thread is initially scheduled.
+
+@param aSelf Pointer to self to facilitate call to member method.
+*/
+TInt CReadDriveThread::ThreadFunction(TAny* aSelf)
+	{
+	__FNLOG("CReadDriveThread::ThreadFunction");
+	CReadDriveThread* self = static_cast<CReadDriveThread*>(aSelf);
+	return self->ReadFromDrive();
+	}
+
+/**
+Reads data from the drive with iOffset and iReadLength into memory pointer iReadBuffer
+and suspends the thread.
+*/
+TInt CReadDriveThread::ReadFromDrive()
+	{
+	__FNLOG("\tCReadDriveThread::ReadFromDrive");
+
+	// One-off convenience variable assignment
+	TBlockDesc* &desc = iThreadContext->iBuffer.iDescWritePtr;
+
+	for (;;)
+		{
+		__PRINT(_L("\tWaiting on Read CS..."));
+		iThreadContext->iCritSect.Wait();
+		// +++ READ CS STARTS HERE +++
+		iThreadRunning = ETrue;
+		iCompleted = EFalse;
+
+		__PRINT1(_L("\tNow using as read buffer: iBuf%d"), iThreadContext->iBuffer.GetBufferNumber(&desc->iBuf));
+ 
+#ifdef MEASURE_AND_DISPLAY_READ_TIME
+		RDebug::Print(_L("\tSCSI: reading %d bytes\n"), desc->iBuf.Length());
+		TTime t0, t1;
+		t0.HomeTime();
+#else
+		__PRINT1(_L("\tSCSI: reading %d bytes\n"), desc->iBuf.Length());
+#endif
+		// Fill read buffer from disk
+		iThreadContext->iError = iThreadContext->iDrive->Read(desc->iByteOffset,
+															  desc->iLength,
+															  desc->iBuf,
+															  iThreadContext->iDrive->IsWholeMediaAccess());
+
+#ifdef MEASURE_AND_DISPLAY_READ_TIME
+		t1.HomeTime();
+		const TTimeIntervalMicroSeconds time = t1.MicroSecondsFrom(t0);
+		const TUint time_ms = I64LOW(time.Int64() / 1000);
+		RDebug::Print(_L("SCSI: read took %d ms\n"), time_ms);
+#endif
+
+		iCompleted = ETrue;
+		iThreadRunning = EFalse;
+		__PRINT(_L("\tSignalling Read CS"));
+		// +++ READ CS ENDS HERE +++
+		iThreadContext->iCritSect.Signal();
+		// Suspend self
+		__PRINT(_L("\tSuspending Read Thread"));
+		RThread().Suspend();
+		}
+	}
+
+/**
+Client read request of a data block from the specified drive. 
+If there is no pre-read data that matches the requested Offset and Length then the drive
+is read and the next pre-read is setup. If there is matching pre-read data available then
+the next pre-read is setup. Finishes by resuming the thread and the ThreadFunciton runs.
+
+@param aDrive Drive to read from.
+@param aOffset Read offset
+@param aLength Length 
+*/
+TBool CReadDriveThread::ReadDriveData(CMassStorageDrive* aDrive,
+									  const TInt64& aOffset,
+									  TUint32 aLength,
+									  TBool aIgnoreCache)
+	{
+	__MT_READ_PRINT2(_L("\nRead10: offs %ld len %d"), aOffset, aLength);
+
+	__PRINT(_L("Waiting on Read CS..."));
+	iThreadContext->iCritSect.Wait();
+	// +++ READ CS STARTS HERE +++
+	__ASSERT_DEBUG(!iThreadRunning, User::Panic(_L("MSDC-THREAD"), 666));
+
+	TBlockDesc* &desc = iThreadContext->iBuffer.iDescReadPtr;
+	TBlockDesc* &bgDesc = iThreadContext->iBuffer.iDescWritePtr;
+
+	if ((!aIgnoreCache) &&
+		(iCompleted) &&
+		(iThreadContext->iError == KErrNone) &&
+		(iThreadContext->iDrive == aDrive) &&
+		(bgDesc->iByteOffset == aOffset) &&
+		(bgDesc->iLength == aLength))
+		{
+		// Good: We pre-read the correct data :-)
+		__MT_READ_PRINT(_L("Match: Using pre-read data :-) :-) :-) :-)"));
+		}
+	else
+		{
+		__MT_READ_PRINT(_L("Not using pre-read data"));
+		if (iThreadContext->iError != KErrNone)
+			{
+			__MT_READ_PRINT1(_L("Pre-read failed: %d"), iThreadContext->iError);
+			}
+		if (iThreadContext->iDrive != aDrive)
+			{
+			__MT_READ_PRINT2(_L("Pre-read drive mismatch: pre 0x%08x / act 0x%08x"),
+							 iThreadContext->iDrive, aDrive);
+			}
+		if (desc->iByteOffset != aOffset)
+			{
+			__MT_READ_PRINT2(_L("Pre-read offset mismatch: pre %ld / act %ld"),
+							 desc->iByteOffset, aOffset);
+			}
+		if (desc->iLength != aLength)
+			{
+			__MT_READ_PRINT2(_L("Pre-read length mismatch: pre %d / act %d"),
+							 desc->iLength, aLength);
+			// Potential optimization: If the pre-read was OK but for more data
+			// than the host is now asking for, we could still satisfy that
+			// request from the pre-read data by shortening the buffer.
+			}
+		// No valid pre-read data was available - so we have to read it now
+		bgDesc->iByteOffset = aOffset;
+		bgDesc->iLength = aLength;
+		TInt err = aDrive->Read(aOffset,
+								aLength,
+								bgDesc->iBuf,
+								aDrive->IsWholeMediaAccess());
+		if (err != KErrNone)
+			{
+			__PRINT1(_L("Read failed, err=%d\n"), err);
+			// +++ READ CS ENDS HERE +++
+			__PRINT(_L("Signalling Read CS..."));
+			iThreadContext->iCritSect.Signal();
+			return EFalse;
+			}
+		}
+
+	// Prepare thread variables for next pre-read attempt by the ReadThread
+	const TInt64 offs_new = aOffset + aLength;
+	iThreadContext->iDrive = aDrive;	// same drive
+	desc->iByteOffset = offs_new;		// next block
+	desc->iLength = aLength;			// same length
+	iCompleted = EFalse;
+	iThreadContext->iBuffer.SwapDesc();
+
+	// +++ READ CS ENDS HERE +++
+	__PRINT(_L("Signalling Read CS..."));
+	iThreadContext->iCritSect.Signal();
+	// Start background read
+	__PRINT(_L("Resuming Read Thread"));
+	iThreadContext->Resume();
+	return ETrue;
+	}
+
+/**
+Discard the read buffer. This is used to force a cache miss when reading from
+the same sectors that were just written.
+*/
+void CReadDriveThread::DiscardRead()
+{
+	__PRINT(_L("Waiting on Read CS in DiscardRead..."));
+	iThreadContext->iCritSect.Wait();
+	// +++ READ CS STARTS HERE +++
+	__PRINT(_L("Discarding pre-read buffer"));
+	iCompleted = EFalse;
+	iThreadContext->iBuffer.iDescReadPtr->iLength = 0;
+
+	// +++ READ CS ENDS HERE +++
+	__PRINT(_L("Signalling Read CS in DiscardRead..."));
+	iThreadContext->iCritSect.Signal();
+}
+#endif // MSDC_MULTITHREADED
+