kernel/eka/memmodel/epoc/flexible/x86/xsched.cia
changeset 0 a41df078684a
child 36 538db54a451d
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/kernel/eka/memmodel/epoc/flexible/x86/xsched.cia	Mon Oct 19 15:55:17 2009 +0100
@@ -0,0 +1,89 @@
+// 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 <x86_mem.h>
+
+GLDEF_C __NAKED__ void DoProcessSwitch()
+	{
+	// Enter with kernel locked
+	// EBX = pointer to new thread (NThread)
+	// EDI = pointer to TScheduler
+	// ESI = pointer to TSubScheduler (SMP only)
+	// Preserve ESI, EDI
+	// eax = new process (DX86PlatProcess)
+	asm("mov eax, [ebx+%0]": : "i"_FOFF(NThreadBase,iAddressSpace)); 
+#ifdef __SMP__
+	asm("cmp eax, [esi+%0]": :"i"_FOFF(TSubScheduler,iAddressSpace));
+#else
+	asm("cmp eax, [edi+%0]": : "i"_FOFF(TScheduler,iAddressSpace));
+#endif
+	asm("jz no_as_switch");
+
+	asm("mov ecx, [eax+%0]": : "i"_FOFF(DMemModelProcess,iPageDir));
+	asm("mov cr3, ecx");
+#ifdef __SMP__
+	asm("mov [esi+%0], eax": :"i"_FOFF(TSubScheduler,iAddressSpace));
+#else
+	asm("mov [edi+%0], eax": : "i"_FOFF(TScheduler,iAddressSpace));
+#endif
+
+	asm("no_as_switch:");
+
+	// Get DThread* from NThread* (former contains latter so we go backwards in memory to get there)
+	asm("mov ecx, 0");
+	asm("lea ecx, [ecx+%0]": : "i"_FOFF(DThread,iNThread));
+	asm("sub ebx, ecx");
+
+	// check for memory being aliased...
+	asm("mov ecx, [ebx+%0]": : "i"_FOFF(DMemModelThread,iAliasLinAddr));
+	asm("cmp ecx, 0");
+	asm("jz done");
+
+	// restore alias...
+	asm("mov edx, [ebx+%0]": : "i"_FOFF(DMemModelThread,iAliasPdePtr));
+	asm("mov eax, [ebx+%0]": : "i"_FOFF(DMemModelThread,iAliasPde));
+	asm("mov [edx], eax");
+	asm("invlpg [ecx]");
+
+	asm("done:");
+	asm("ret");
+	};
+
+
+
+__NAKED__ void DMemModelThread::RestoreAddressSpace()
+	{
+#ifndef __SMP__
+	//SMP FIXME
+	asm("mov eax, [%a0]": : "i"(&TheScheduler.iCurrentThread));
+
+	// edx = current thread owning process...
+	asm("mov edx, 0");
+	asm("lea edx, [edx+%0]": : "i"_FOFF(DThread,iNThread));
+	asm("neg edx");
+	asm("mov edx, [eax+edx+%0]": : "i"_FOFF(DThread,iOwningProcess));
+
+	// update page directory and address space values...
+	asm("cli");
+	asm("mov [%a0], edx": :"i"(&TheScheduler.iAddressSpace));
+	asm("mov [eax+%0], edx": : "i"_FOFF(NThreadBase,iAddressSpace));
+	asm("mov edx, [edx+%0]": : "i"_FOFF(DMemModelProcess,iPageDir));
+	asm("mov cr3, edx");
+	asm("sti");
+#endif
+	asm("ret");
+	}
+
+