--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/kernel/eka/memmodel/epoc/moving/mdefrag.cpp	Mon Oct 19 15:55:17 2009 +0100
@@ -0,0 +1,217 @@
+// Copyright (c) 2006-2009 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\memmodel\epoc\moving\mdefrag.cpp
+// 
+//
+
+#include <memmodel.h>
+#include <defrag.h>
+#include "mmboot.h"
+#include <mmubase.inl>
+#include <ramalloc.h>
+#include "cache_maintenance.h"
+
+/*
+ * Move a kernel page from aOld to aNew, updating the page table in aChunk.
+ * Enter with system locked, exit with system unlocked (!!)
+ * Must hold RAM alloc mutex.
+ */
+TInt Mmu::MoveKernelPage(DChunk* aChunk, TUint32 aOffset, TPhysAddr aOld, TPhysAddr& aNew, TUint aBlockZoneId, TBool aBlockRest)
+	{
+	__KTRACE_OPT(KMMU,Kern::Printf("Mmu::MoveKernelPage() off=%08x old=%08x",aOffset,aOld));
+	Mmu& m=Mmu::Get();
+	
+	// Release the system lock - the kernel chunks can't ever be freed
+	// and the ramalloc mutex protects us from decommit.
+	NKern::UnlockSystem();
+
+	DMemModelChunk* chunk = (DMemModelChunk*)aChunk;
+
+	// Allocate new page, map it uncached but buffered, and find old mapping
+	TPhysAddr newPage;
+	if (m.AllocRamPages(&newPage, 1, EPageMovable, aBlockZoneId, aBlockRest) != KErrNone)
+		return KErrNoMemory;
+	TLinAddr vOld = (TLinAddr)chunk->iBase + aOffset;
+	TLinAddr vNew = m.MapTemp(newPage, EFalse);
+	
+	// Find page table for mapping
+	TInt ptid=m.GetPageTableId(vOld);
+	if(ptid<0)
+		Panic(EDefragKernelChunkNoPageTable);
+
+	// With the system lock, ask Mmu to remap the page.
+	// This will copy and remap it with interrupts disabled, while
+	// avoiding touching any cache lines on the heap.
+	NKern::LockSystem();
+	m.RemapKernelPage(ptid, vOld, vNew, newPage, chunk->iPtePermissions);
+
+	// update new pageinfo, clear old, then done with system lock.
+	SPageInfo* oldpi = SPageInfo::FromPhysAddr(aOld);
+	SPageInfo* pi = SPageInfo::FromPhysAddr(newPage);
+	pi->Set(oldpi->Type(),oldpi->Owner(),oldpi->Offset());
+	oldpi->SetUnused();
+	NKern::UnlockSystem();
+
+	// Remove temporary new page mapping
+	m.UnmapTemp();
+
+	// Remove old page from external cache - RemapKernelPage has already removed it from internal cache.
+	CacheMaintenance::PageToReusePhysicalCache(aOld);
+
+	// Free old page
+#ifdef _DEBUG
+	m.ClearPages(1, (TPhysAddr*)(aOld|1));
+#endif
+	m.iRamPageAllocator->FreeRamPage(aOld, EPageMovable);
+
+	aNew = newPage;
+	return KErrNone;
+	}
+
+/* 
+ * These pages don't exist on moving memory model, no need to move them
+ * but this function must exist to make the kernel link.
+ */
+TInt Mmu::MoveCodeSegMemoryPage(DMemModelCodeSegMemory* /*aCodeSegMemory*/, TUint32 /*aOffset*/, TPhysAddr /*aOld*/,
+		TPhysAddr& /*aNew*/, TUint /*aBlockZoneId*/, TBool /*aBlockRest*/)
+	{
+	NKern::UnlockSystem();
+	return KErrNotSupported;
+	}
+
+/*
+ * Move a code chunk page from aOld to aNew, updating the page table in aChunk.
+ * Enter with system locked, exit with system unlocked (!!)
+ * Must hold RAM alloc mutex.
+ */
+TInt Mmu::MoveCodeChunkPage(DChunk* aChunk, TUint32 aOffset, TPhysAddr aOld, TPhysAddr& aNew, TUint aBlockZoneId, TBool aBlockRest)
+	{
+	__KTRACE_OPT(KMMU,Kern::Printf("Mmu::MoveCodeChunkPage() off=%08x old=%08x",aOffset,aOld));
+	Mmu& m=Mmu::Get();
+
+	// look up the code seg that corresponds to this page
+	TLinAddr aLinearAddress = (TLinAddr)(aChunk->Base() + aOffset);
+	DMemModelCodeSeg* codeseg = (DMemModelCodeSeg*)DCodeSeg::CodeSegsByAddress.Find(aLinearAddress);
+
+	// if the code seg is not done loading yet, we can't move it the easy way
+	// also, if it's being unloaded the codeseg will have gone.
+	if (!codeseg || !(codeseg->iMark & DCodeSeg::EMarkLoaded))
+		{
+		NKern::UnlockSystem();
+		return KErrInUse;
+		}
+
+	// Release system lock as page can't be decommitted while we hold ramalloc mutex
+	NKern::UnlockSystem();
+
+	// Allocate new page, map it uncached but buffered, and find old mapping
+	TPhysAddr newPage;
+	if (m.AllocRamPages(&newPage, 1, EPageMovable, aBlockZoneId, aBlockRest) != KErrNone)
+		return KErrNoMemory;
+	TLinAddr vOld = aLinearAddress;
+	TLinAddr vNew = m.MapTemp(newPage, EFalse);
+	
+	// Copy the page and remap it
+	pagecpy((TAny*)vNew, (TAny*)vOld);
+	NKern::LockSystem();
+	// Substitute drains the write buffer for us during the remap.
+	aChunk->Substitute(aOffset, aOld, newPage);
+	NKern::UnlockSystem();
+
+	// Remove temporary new page mapping
+	m.UnmapTemp();
+
+	// Remove old page from physical cache
+	CacheMaintenance::PageToReusePhysicalCache(aOld);
+
+	// Free old page
+#ifdef _DEBUG
+	m.ClearPages(1, (TPhysAddr*)(aOld|1));
+#endif
+	m.iRamPageAllocator->FreeRamPage(aOld, EPageMovable);
+
+	aNew = newPage;
+	return KErrNone;
+	}
+
+/*
+ * Move a data chunk page from aOld to aNew, updating the page table in aChunk.
+ * Enter with system locked, exit with system unlocked (!!)
+ * Must hold RAM alloc mutex.
+ */
+TInt Mmu::MoveDataChunkPage(DChunk* aChunk, TUint32 aOffset, TPhysAddr aOld, TPhysAddr& aNew, TUint aBlockZoneId, TBool aBlockRest)
+	{
+	__KTRACE_OPT(KMMU,Kern::Printf("Mmu::MoveDataChunkPage() off=%08x old=%08x",aOffset,aOld));
+	Mmu& m=Mmu::Get();
+	TInt r;
+
+	// Release system lock as page can't be decommitted while we hold ramalloc mutex
+	NKern::UnlockSystem();
+
+	// Allocate new page, map it uncached but buffered
+	TPhysAddr newPage;
+	if (m.AllocRamPages(&newPage, 1, EPageMovable, aBlockZoneId, aBlockRest) != KErrNone)
+		return KErrNoMemory;
+	TLinAddr vNew = m.MapTemp(newPage, EFalse);
+
+	// Mark the PTE as inaccessible to avoid the data being overwritten while we copy
+	// This also takes care of the cache requirements to alias the page elsewhere,
+	// since it can't be copied from an inaccessible PTE
+	DisablePageModification((DMemModelChunk*)aChunk, aOffset);
+	TLinAddr vOldAlias = m.MapSecondTemp(aOld, ETrue);
+
+	// Copy the page's contents and remap its PTE
+	pagecpy((TAny*)vNew, (TAny*)vOldAlias);
+	NKern::LockSystem();
+	if (iDisabledPte != NULL)
+		{
+		// Access wasn't reenabled, so we can continue
+		aChunk->Substitute(aOffset, aOld, newPage);
+		iDisabledAddr = 0;
+		iDisabledPte = NULL;
+		iDisabledOldVal = 0;
+		r = KErrNone;
+		}
+	else
+		r = KErrInUse;
+	NKern::UnlockSystem();
+
+	// Remove temporary page mappings
+	CacheMaintenance::PageToReuseVirtualCache(vOldAlias);
+	m.UnmapTemp();
+	m.UnmapSecondTemp();
+
+	if (r == KErrNone)
+		{
+		// Remove old page from physical cache - DisablePageModification removed it from L1 already
+		CacheMaintenance::PageToReusePhysicalCache(aOld);
+		}
+
+	if (r == KErrNone)
+		{
+		// Free old page
+#ifdef _DEBUG
+		m.ClearPages(1, (TPhysAddr*)(aOld|1));
+#endif
+		m.iRamPageAllocator->FreeRamPage(aOld, EPageMovable);
+		aNew = newPage;
+		}
+	else
+		{
+		// Free new page
+		m.iRamPageAllocator->FreeRamPage(newPage, EPageMovable);
+		}
+
+	return r;
+	}