--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/kernel/eka/drivers/locmedia/dmasupport.h	Mon Oct 19 15:55:17 2009 +0100
@@ -0,0 +1,156 @@
+// 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:
+// e32\include\drivers\dmasupport.h
+// 
+//
+
+#ifndef DMASUPPORT_H
+#define DMASUPPORT_H
+
+#include "plat_priv.h"
+#include <d32locd.h>
+
+
+class TLocDrvRequest;
+
+/**
+@internalTechnology
+@prototype
+
+Class used for read / write requests to the local media subsystem to gain access
+to physical memory address to make use of DMA without the need of an intermediate buffer.
+*/
+class DDmaHelper : public DBase
+	{
+public:
+
+	enum TMemoryType
+		{
+		EUnknown,
+		EFileServerChunk,
+		ESharedChunk,
+		};
+
+	/**
+	Class used to describe a number of contiguous physical pages
+	*/
+	class TPageList
+		{
+	public:
+		TPhysAddr iAddress;	// address of page
+		TInt 	  iLength;
+		};
+
+public:
+	DDmaHelper();
+	~DDmaHelper();
+	
+	TInt Construct(TInt aLength, TInt aMediaBlockSize, TInt aDmaAlignment);
+	
+	TInt SendReceive(TLocDrvRequest& aReq, TLinAddr aLinAddress);
+	TInt GetPhysicalAddress(TPhysAddr& aAddr, TInt& aLen);
+
+#ifdef __DEMAND_PAGING__
+	static TInt GetPhysicalAddress(TLocDrvRequest& aReq, TPhysAddr& aAddr, TInt& aLen);
+#endif
+	inline TInt PageSize()	const { return iPageSize; }
+	
+private:
+
+	static inline TInt PageSizeLog2();
+	static inline TBool IsPageAligned(TLinAddr aAddr);
+	static inline TLinAddr PageAlign(TLinAddr aAddr);
+	static inline TLinAddr PageOffset(TLinAddr aAddr);
+
+	inline TInt MaxFragLength()	const;
+	inline void SetFragLength(TInt aLength);
+	inline TInt FragLength()	const;
+	inline TInt LengthRemaining() const;
+	inline TUint32 LengthConsumed() const;
+
+	inline TBool IsDmaAligned(TLinAddr aAddr);
+	inline TBool IsBlockAligned(TInt64 aPos);
+	inline TInt64 BlockAlign(TInt64 aPos);
+	inline TInt BlockOffset(TInt64 aPos);
+
+	inline TLinAddr LinAddress() const;
+
+	void ResetPageLists();
+
+	TInt UpdateRemoteDescriptorLength(TInt aLength);
+
+	TInt RequestStart();
+	void RequestEnd();
+	void BuildPageList();
+	void ReleasePages(TLinAddr aAddr);
+
+private:
+	TInt iMediaBlockSize;		// Minimum transfer size (bytes) for the media.
+	TInt64 iMediaBlockSizeMask;	// iMediaBlockSize - 1
+	TInt iDmaAlignment;			// DMA Alignment req for media's DMA controller i.e. word alignment
+
+	static TInt iPageSize;		// Memory page size in bytes (e.g. 4096 Bytes)
+	static TInt iPageSizeLog2;	// Log2 of page size (e.g. 4096 -> 12)
+	static TInt iPageSizeMsk;	// Mask of page size (e.g. 4096-1 -> 4095)
+	TInt iMaxPages;				// Maximum number of pages that can be stored by this object
+
+	DThread* iRemoteThread;		// 
+	DThread* iCurrentThread;	//  
+	DThread* iOwningThread;		// Thread owning remote descriptor, either iRemoteThread or iCurrentThread
+
+	TLocDrvRequest* iReq;		// Current TLocDrvRequest
+	
+	// The following attributes are copied from the current TLocDrvRequest
+	TInt iReqId;
+	TInt iReqRemoteDesOffset;
+	TInt iReqFlags;				// 
+	TInt iReqLenClient;			// length of data requested by client (unmodified)
+	TInt64 iReqPosClient;		// position of data requested by client (unmodified)
+
+	TLinAddr iLinAddressUser;	// linear address of client buffer in user process
+	TLinAddr iLinAddressKernel;	// linear address of client buffer in kernel process
+	TInt iFragLen;				// length of data to be read into physical pages (possibly < a multiple of the page-size)
+	TInt iFragLenRemaining;		// length of data to be read left in this fragment
+
+	TMemoryType iMemoryType;
+	
+	/** array of (possibly non-contiguous) pages */
+	TPhysAddr* iPageArray;
+	TInt iPageArrayCount;
+	
+	/** list of contiguous pages */
+	TPageList* iPageList;
+	TInt iPageListCount;
+
+	TInt iIndex;					// Current memory fragment index
+	
+	/** Represents the current read/write position in terms of an offset 
+	from the start of the caller's linear address */ 
+	TInt iLenConsumed;				// Offset from start of client buffer
+
+	DChunk* iChunk;					// Shared chunk object in use
+	TInt    iChunkOffset;			// Offset within shared chunk
+	TUint32 iMapAttr;				// mmu mapping attributes for the Shared chunk or pinned physical memory.
+	TUint32 iPhysAddr;				// Physical Address of chunk (if contiguous)
+
+	TInt iLockCount;				// Prevent 2+ threads accessing this object
+	
+	TBool iPhysPinningAvailable;    // True if physical memory pinning Kernel interface is available
+	TUint  iPageColour;				// Mapping colour of the first page in iPageArray.
+	TPhysicalPinObject* iPhysicalPinObject;	// Physical pinning object.
+	};
+
+
+
+#endif	// DMASUPPORT_H