reactos/ntoskrnl/vdm/vdmmain.c

   1 /*
   2  * PROJECT:         ReactOS Kernel
   3  * LICENSE:         GPL - See COPYING in the top level directory
   4  * FILE:            ntoskrnl/vdm/vdmmain.c
   5  * PURPOSE:         VDM Support Services
   6  * PROGRAMMERS:     Alex Ionescu (alex.ionescu@reactos.org)
   7  */
   8
   9 /* INCLUDES ******************************************************************/
  10
  11 #include <ntoskrnl.h>
  12 #define NDEBUG
  13 #include <debug.h>
  14
  15 /* GLOBALS *******************************************************************/
  16
  17 static UCHAR OrigIVT[1024];
  18 static UCHAR OrigBDA[256];
  19
  20 /* PRIVATE FUNCTIONS *********************************************************/
  21
  22 VOID
  23 INIT_FUNCTION
  24 NtEarlyInitVdm(VOID)
  25 {
  26     PCHAR start = MmCreateHyperspaceMapping(0);
  27     memcpy(OrigIVT, start, 1024);
  28     memcpy(OrigBDA, start+0x400, 256);
  29     MmDeleteHyperspaceMapping(start);
  30 }
  31
  32 VOID
  33 NTAPI
  34 Ki386VdmEnablePentiumExtentions(VOID)
  35 {
  36     DPRINT1("VME detected but not yet supported\n");
  37 }
  38
  39 VOID
  40 NTAPI
  41 KeI386VdmInitialize(VOID)
  42 {
  43     NTSTATUS Status;
  44     OBJECT_ATTRIBUTES ObjectAttributes;
  45     HANDLE RegHandle;
  46     UNICODE_STRING Name;
  47     UCHAR KeyValueInfo[sizeof(KEY_VALUE_BASIC_INFORMATION) + 30];
  48     ULONG ReturnLength;
  49
  50     /* Make sure that there is a WOW key */
  51     RtlInitUnicodeString(&Name,
  52                          L"\\Registry\\Machine\\System\\CurrentControlSet\\"
  53                          L"Control\\Wow");
  54     InitializeObjectAttributes(&ObjectAttributes,
  55                                &Name,
  56                                OBJ_CASE_INSENSITIVE,
  57                                NULL,
  58                                NULL);
  59     Status = ZwOpenKey(&RegHandle, KEY_READ, &ObjectAttributes);
  60     if (!NT_SUCCESS(Status)) return;
  61
  62     /* Check if VME is enabled */
  63     RtlInitUnicodeString(&Name, L"DisableVme");
  64     Status = ZwQueryValueKey(RegHandle,
  65                              &Name,
  66                              KeyValueBasicInformation,
  67                              &KeyValueInfo,
  68                              sizeof(KeyValueInfo),
  69                              &ReturnLength);
  70     if (!NT_SUCCESS(Status))
  71     {
  72         /* Not present, so check if the CPU supports VME */
  73         if (KeGetPcr()->Prcb->FeatureBits & KF_V86_VIS)
  74         {
  75             /* Enable them. FIXME: Use IPI */
  76             Ki386VdmEnablePentiumExtentions();
  77             KeI386VirtualIntExtensions = TRUE;
  78         }
  79     }
  80
  81     /* Close the key */
  82     ZwClose(RegHandle);
  83 }
  84
  85 /* PUBLIC FUNCTIONS **********************************************************/
  86
  87 /*
  88  * @implemented
  89  */
  90 NTSTATUS
  91 NTAPI
  92 NtVdmControl(IN ULONG ControlCode,
  93              IN PVOID ControlData)
  94 {
  95     NTSTATUS Status;
  96     PAGED_CODE();
  97
  98     /* Check which control code this is */
  99     switch (ControlCode)
 100     {
 101         /* VDM Execution start */
 102         case VdmStartExecution:
 103
 104             /* Call the sub-function */
 105             Status = VdmpStartExecution();
 106             break;
 107
 108         case VdmInitialize:
 109
 110             /* Pretty much a hack, since a lot more needs to happen */
 111             memcpy(ControlData, OrigIVT, 1024);
 112             memcpy((PVOID)((ULONG_PTR)ControlData + 1024), OrigBDA, 256);
 113             Status = STATUS_SUCCESS;
 114             break;
 115
 116         default:
 117
 118             /* Unsupported */
 119             DPRINT1("Unknown VDM call: %lx\n", ControlCode);
 120             Status = STATUS_INVALID_PARAMETER;
 121     }
 122
 123     /* Return the status */
 124     return Status;
 125 }