memory.h File Reference

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Macros
#define	TOTAL_PAGES   (MAX_ADDRESS / PAGE_SIZE)

Typedefs
typedef VOID(FASTCALL *	PMEMORY_READ_HANDLER) (ULONG Address, PVOID Buffer, ULONG Size)
typedef BOOLEAN(FASTCALL *	PMEMORY_WRITE_HANDLER) (ULONG Address, PVOID Buffer, ULONG Size)

Functions
BOOLEAN	MemInitialize (VOID)
VOID	MemCleanup (VOID)
VOID	MemExceptionHandler (ULONG FaultAddress, BOOLEAN Writing)
VOID FASTCALL	EmulatorReadMemory (PFAST486_STATE State, ULONG Address, PVOID Buffer, ULONG Size)
VOID FASTCALL	EmulatorWriteMemory (PFAST486_STATE State, ULONG Address, PVOID Buffer, ULONG Size)
VOID FASTCALL	EmulatorCopyMemory (PFAST486_STATE State, ULONG DestAddress, ULONG SrcAddress, ULONG Size)
VOID	EmulatorSetA20 (BOOLEAN Enabled)
BOOLEAN	EmulatorGetA20 (VOID)
BOOL	MemInstallFastMemoryHook (PVOID Address, ULONG Size, PMEMORY_READ_HANDLER ReadHandler, PMEMORY_WRITE_HANDLER WriteHandler)
BOOL	MemRemoveFastMemoryHook (PVOID Address, ULONG Size)
BOOLEAN	MemQueryMemoryZone (ULONG StartAddress, PULONG Length, PBOOLEAN Hooked)

Macro Definition Documentation

TOTAL_PAGES

#define TOTAL_PAGES   (MAX_ADDRESS / PAGE_SIZE)

Definition at line 14 of file memory.h.

Typedef Documentation

PMEMORY_READ_HANDLER

typedef VOID(FASTCALL * PMEMORY_READ_HANDLER) (ULONG Address, PVOID Buffer, ULONG Size)

Definition at line 16 of file memory.h.

PMEMORY_WRITE_HANDLER

typedef BOOLEAN(FASTCALL * PMEMORY_WRITE_HANDLER) (ULONG Address, PVOID Buffer, ULONG Size)

Definition at line 24 of file memory.h.

Function Documentation

EmulatorCopyMemory()

VOID FASTCALL EmulatorCopyMemory	(	PFAST486_STATE	State,
		ULONG	DestAddress,
		ULONG	SrcAddress,
		ULONG	Size
	)

Definition at line 219 of file memory.c.

{
    /*
     * Guest-to-guest memory copy
     */
 
    // FIXME: This is a temporary implementation of a more useful functionality
    // which should be a merge of EmulatorReadMemory & EmulatorWriteMemory without
    // any local external buffer.
    // NOTE: Process heap is by default serialized (unless one specifies it shouldn't).
    static BYTE StaticBuffer[8192]; // Smallest static buffer we can use.
    static PVOID HeapBuffer = NULL; // Always-growing heap buffer. Use it in case StaticBuffer is too small.
    static ULONG HeapBufferSize = 0;
    PVOID LocalBuffer;              // Points to either StaticBuffer or HeapBuffer
 
    if (Size <= sizeof(StaticBuffer))
    {
        /* Use the static buffer */
        LocalBuffer = StaticBuffer;
    }
    else if (/* sizeof(StaticBuffer) <= Size && */ Size <= HeapBufferSize)
    {
        /* Use the heap buffer */
        ASSERT(HeapBufferSize > 0 && HeapBuffer != NULL);
        LocalBuffer = HeapBuffer;
    }
    else // if (Size > HeapBufferSize)
    {
        /* Enlarge the heap buffer and use it */
 
        if (HeapBuffer == NULL)
        {
            /* First allocation */
            LocalBuffer = RtlAllocateHeap(RtlGetProcessHeap(), 0, Size);
        }
        else
        {
            /* Reallocation */
            LocalBuffer = RtlReAllocateHeap(RtlGetProcessHeap(), 0 /* HEAP_GENERATE_EXCEPTIONS */, HeapBuffer, Size);
        }
        ASSERT(LocalBuffer != NULL); // We must succeed! TODO: Handle it more properly.
        HeapBuffer = LocalBuffer;    // HeapBuffer is now reallocated.
        HeapBufferSize = Size;
    }
 
    /* Perform memory copy */
    EmulatorReadMemory( State, SrcAddress , LocalBuffer, Size);
    EmulatorWriteMemory(State, DestAddress, LocalBuffer, Size);
 
    // if (LocalBuffer != StaticBuffer)
    //     RtlFreeHeap(RtlGetProcessHeap(), 0, LocalBuffer);
 
    // Note that we don't free HeapBuffer since it's an always-growing buffer.
    // It is freed when NTVDM termiantes.
}

Referenced by VidBiosScrollWindow().

EmulatorGetA20()

BOOLEAN EmulatorGetA20

(

VOID

)

Definition at line 280 of file memory.c.

{
    return A20Line;
}

Referenced by PS2WriteControl(), and XmsBopProcedure().

EmulatorReadMemory()

VOID FASTCALL EmulatorReadMemory	(	PFAST486_STATE	State,
		ULONG	Address,
		PVOID	Buffer,
		ULONG	Size
	)

Definition at line 142 of file memory.c.

{
    ULONG i, Offset, Length;
    ULONG FirstPage, LastPage;
 
    UNREFERENCED_PARAMETER(State);
 
    /* Mirror 0x000FFFF0 at 0xFFFFFFF0 */
    if (Address >= 0xFFFFFFF0) Address -= 0xFFF00000;
 
    /* If the A20 line is disabled, mask bit 20 */
    if (!A20Line) Address &= ~(1 << 20);
 
    if ((Address + Size - 1) >= MAX_ADDRESS)
    {
        ULONG ExtraStart = (Address < MAX_ADDRESS) ? MAX_ADDRESS - Address : 0;
 
        /* Fill the memory that was above the limit with 0xFF */
        RtlFillMemory((PVOID)((ULONG_PTR)Buffer + ExtraStart), Size - ExtraStart, 0xFF);
 
        if (Address < MAX_ADDRESS) Size = MAX_ADDRESS - Address;
        else return;
    }
 
    FirstPage = Address >> 12;
    LastPage = (Address + Size - 1) >> 12;
 
    if (FirstPage == LastPage)
    {
        ReadPage(PageTable[FirstPage], Address, Buffer, Size);
    }
    else
    {
        for (i = FirstPage; i <= LastPage; i++)
        {
            Offset = (i == FirstPage) ? (Address & (PAGE_SIZE - 1)) : 0;
            Length = ((i == LastPage) ? (Address + Size - (LastPage << 12)) : PAGE_SIZE) - Offset;
 
            ReadPage(PageTable[i], (i << 12) + Offset, Buffer, Length);
            Buffer = (PVOID)((ULONG_PTR)Buffer + Length);
        }
    }
}

Referenced by CpuInitialize(), DmaRequest(), DosWriteFile(), EmulatorCopyMemory(), PaintMouseCursor(), VidBiosDrawGlyph(), VidBiosVideoService(), and WriteDisk().

EmulatorSetA20()

VOID EmulatorSetA20

(

BOOLEAN

Enabled

)

Definition at line 275 of file memory.c.

{
    A20Line = Enabled;
}

Referenced by PS2WriteData(), XmsLocalDisableA20(), and XmsLocalEnableA20().

EmulatorWriteMemory()

VOID FASTCALL EmulatorWriteMemory	(	PFAST486_STATE	State,
		ULONG	Address,
		PVOID	Buffer,
		ULONG	Size
	)

Definition at line 186 of file memory.c.

{
    ULONG i, Offset, Length;
    ULONG FirstPage, LastPage;
 
    UNREFERENCED_PARAMETER(State);
 
    /* If the A20 line is disabled, mask bit 20 */
    if (!A20Line) Address &= ~(1 << 20);
 
    if (Address >= MAX_ADDRESS) return;
    Size = min(Size, MAX_ADDRESS - Address);
 
    FirstPage = Address >> 12;
    LastPage = (Address + Size - 1) >> 12;
 
    if (FirstPage == LastPage)
    {
        WritePage(PageTable[FirstPage], Address, Buffer, Size);
    }
    else
    {
        for (i = FirstPage; i <= LastPage; i++)
        {
            Offset = (i == FirstPage) ? (Address & (PAGE_SIZE - 1)) : 0;
            Length = ((i == LastPage) ? (Address + Size - (LastPage << 12)) : PAGE_SIZE) - Offset;
 
            WritePage(PageTable[i], (i << 12) + Offset, Buffer, Length);
            Buffer = (PVOID)((ULONG_PTR)Buffer + Length);
        }
    }
}

Referenced by CpuInitialize(), DmaRequest(), DosReadFile(), EmulatorCopyMemory(), EraseMouseCursor(), PaintMouseCursor(), ReadDisk(), VidBiosClearScreen(), VidBiosDrawGlyph(), and VidBiosScrollWindow().

MemCleanup()

VOID MemCleanup

(

VOID

)

Definition at line 783 of file memory.c.

{
    NTSTATUS Status;
    SIZE_T MemorySize = MAX_ADDRESS;
    PLIST_ENTRY Pointer;
 
    while (!IsListEmpty(&HookList))
    {
        Pointer = RemoveHeadList(&HookList);
        RtlFreeHeap(RtlGetProcessHeap(), 0, CONTAINING_RECORD(Pointer, MEM_HOOK, Entry));
    }
 
    /* Decommit the VDM memory */
    Status = NtFreeVirtualMemory(NtCurrentProcess(),
                                 &BaseAddress,
                                 &MemorySize,
#ifndef STANDALONE
                                 MEM_DECOMMIT
#else
                                 MEM_RELEASE
#endif
                                 );
    if (!NT_SUCCESS(Status))
    {
        DPRINT1("NTVDM: Failed to decommit VDM memory, Status 0x%08lx\n", Status);
    }
}

Referenced by EmulatorCleanup().

MemExceptionHandler()

VOID MemExceptionHandler	(	ULONG	FaultAddress,
		BOOLEAN	Writing
	)

Definition at line 286 of file memory.c.

{
    PMEM_HOOK Hook = PageTable[FaultAddress >> 12];
    DPRINT("The memory at 0x%08X could not be %s.\n", FaultAddress, Writing ? "written" : "read");
 
    /* Exceptions are only supposed to happen when using VDD-style memory hooks */
    ASSERT(FaultAddress < MAX_ADDRESS && Hook != NULL && Hook->hVdd != NULL);
 
    /* Call the VDD handler */
    Hook->VddHandler(REAL_TO_PHYS(FaultAddress), (ULONG)Writing);
}

Referenced by CpuExceptionFilter().

MemInitialize()

BOOLEAN MemInitialize

(

VOID

)

Definition at line 723 of file memory.c.

{
    NTSTATUS Status;
    SIZE_T MemorySize = MAX_ADDRESS; // See: kernel32/client/vdm.c!BaseGetVdmConfigInfo
 
    InitializeListHead(&HookList);
 
#ifndef STANDALONE
 
    /*
     * The reserved region starts from the very first page.
     * We need to commit the reserved first 16 MB virtual address.
     *
     * NOTE: NULL has another signification for NtAllocateVirtualMemory.
     */
    BaseAddress = (PVOID)1;
 
    /*
     * Since to get NULL, we allocated from 0x1, account for this.
     * See also: kernel32/client/proc.c!CreateProcessInternalW
     */
    MemorySize -= 1;
 
#else
 
    /* Allocate it anywhere */
    BaseAddress = NULL;
 
#endif
 
    Status = NtAllocateVirtualMemory(NtCurrentProcess(),
                                     &BaseAddress,
                                     0,
                                     &MemorySize,
#ifndef STANDALONE
                                     MEM_COMMIT,
#else
                                     MEM_RESERVE | MEM_COMMIT,
#endif
                                     PAGE_EXECUTE_READWRITE);
    if (!NT_SUCCESS(Status))
    {
        wprintf(L"FATAL: Failed to commit VDM memory, Status 0x%08lx\n", Status);
        return FALSE;
    }
 
#ifndef STANDALONE
    ASSERT(BaseAddress == NULL);
#endif
 
    /*
     * For diagnostics purposes, we fill the memory with INT 0x03 codes
     * so that if a program wants to execute random code in memory, we can
     * retrieve the exact CS:IP where the problem happens.
     */
    RtlFillMemory(BaseAddress, MAX_ADDRESS, 0xCC);
    return TRUE;
}

Referenced by EmulatorInitialize().

MemInstallFastMemoryHook()

BOOL MemInstallFastMemoryHook	(	PVOID	Address,
		ULONG	Size,
		PMEMORY_READ_HANDLER	ReadHandler,
		PMEMORY_WRITE_HANDLER	WriteHandler
	)

Definition at line 299 of file memory.c.

{
    PMEM_HOOK Hook;
    ULONG i;
    ULONG FirstPage = (ULONG_PTR)Address >> 12;
    ULONG LastPage = ((ULONG_PTR)Address + Size - 1) >> 12;
    PLIST_ENTRY Pointer;
 
    /* Make sure none of these pages are already allocated */
    for (i = FirstPage; i <= LastPage; i++)
    {
        if (PageTable[i] != NULL) return FALSE;
    }
 
    for (Pointer = HookList.Flink; Pointer != &HookList; Pointer = Pointer->Flink)
    {
        Hook = CONTAINING_RECORD(Pointer, MEM_HOOK, Entry);
 
        if (Hook->hVdd == NULL
            && Hook->FastReadHandler == ReadHandler
            && Hook->FastWriteHandler == WriteHandler)
        {
            break;
        }
    }
 
    if (Pointer == &HookList)
    {
        /* Create and initialize a new hook entry... */
        Hook = RtlAllocateHeap(RtlGetProcessHeap(), 0, sizeof(*Hook));
        if (Hook == NULL) return FALSE;
 
        Hook->hVdd = NULL;
        Hook->Count = 0;
        Hook->FastReadHandler = ReadHandler;
        Hook->FastWriteHandler = WriteHandler;
 
        /* ... and add it to the list of hooks */
        InsertTailList(&HookList, &Hook->Entry);
    }
 
    /* Increase the number of pages this hook has */
    Hook->Count += LastPage - FirstPage + 1;
 
    /* Add the hook entry to the page table */
    for (i = FirstPage; i <= LastPage; i++) PageTable[i] = Hook;
 
    return TRUE;
}

Referenced by EmsDrvInitialize(), VgaWriteGc(), VgaWritePort(), and WriteProtectRom().

MemQueryMemoryZone()

BOOLEAN MemQueryMemoryZone	(	ULONG	StartAddress,
		PULONG	Length,
		PBOOLEAN	Hooked
	)

Definition at line 381 of file memory.c.

{
    ULONG Page = StartAddress >> 12;
    if (Page >= TOTAL_PAGES) return FALSE;
 
    *Length = 0;
    *Hooked = PageTable[Page] != NULL;
 
    while (Page < TOTAL_PAGES && (PageTable[Page] != NULL) == *Hooked)
    {
        *Length += PAGE_SIZE;
        Page++;
    }
 
    return TRUE;
}

Referenced by BiosMiscService().

MemRemoveFastMemoryHook()

BOOL MemRemoveFastMemoryHook	(	PVOID	Address,
		ULONG	Size
	)

Definition at line 353 of file memory.c.

{
    PMEM_HOOK Hook;
    ULONG i;
    ULONG FirstPage = (ULONG_PTR)Address >> 12;
    ULONG LastPage = ((ULONG_PTR)Address + Size - 1) >> 12;
 
    if (Size == 0) return FALSE;
 
    for (i = FirstPage; i <= LastPage; i++)
    {
        Hook = PageTable[i];
        if (Hook == NULL || Hook->hVdd != NULL) continue;
 
        if (--Hook->Count == 0)
        {
            /* This hook has no more pages */
            RemoveEntryList(&Hook->Entry);
            RtlFreeHeap(RtlGetProcessHeap(), 0, Hook);
        }
 
        PageTable[i] = NULL;
    }
 
    return TRUE;
}

Referenced by EmsDrvCleanup(), VgaCleanup(), VgaWriteGc(), VgaWritePort(), and WriteUnProtectRom().