reactos/subsys/csrss/video.c

   1 /* $Id$
   2  *
   3  * ReactOS Project
   4  */
   5
   6 #include <windows.h>
   7 #include <ddk/ntddk.h>
   8 #include <ddk/ntapi.h>
   9 #include <rosrtl/string.h>
  10
  11 ULONG
  12 InitializeVideoAddressSpace(VOID)
  13 {
  14    OBJECT_ATTRIBUTES ObjectAttributes;
  15    UNICODE_STRING PhysMemName;
  16    NTSTATUS Status;
  17    HANDLE PhysMemHandle;
  18    PVOID BaseAddress;
  19    PVOID NullAddress;
  20    LARGE_INTEGER Offset;
  21    ULONG ViewSize;
  22    CHAR IVT[1024];
  23    CHAR BDA[256];
  24
  25    /*
  26     * Open the physical memory section
  27     */
  28    RtlRosInitUnicodeStringFromLiteral(&PhysMemName, L"\\Device\\PhysicalMemory");
  29    InitializeObjectAttributes(&ObjectAttributes,
  30                               &PhysMemName,
  31                               0,
  32                               NULL,
  33                               NULL);
  34    Status = ZwOpenSection(&PhysMemHandle, SECTION_ALL_ACCESS,
  35                           &ObjectAttributes);
  36    if (!NT_SUCCESS(Status))
  37      {
  38         DbgPrint("Couldn't open \\Device\\PhysicalMemory\n");
  39         return(0);
  40      }
  41
  42    /*
  43     * Map the BIOS and device registers into the address space
  44     */
  45    Offset.QuadPart = 0xa0000;
  46    ViewSize = 0x100000 - 0xa0000;
  47    BaseAddress = (PVOID)0xa0000;
  48    Status = NtMapViewOfSection(PhysMemHandle,
  49                                NtCurrentProcess(),
  50                                &BaseAddress,
  51                                0,
  52                                8192,
  53                                &Offset,
  54                                &ViewSize,
  55                                ViewUnmap,
  56                                0,
  57                                PAGE_EXECUTE_READWRITE);
  58    if (!NT_SUCCESS(Status))
  59      {
  60         DbgPrint("Couldn't map physical memory (%x)\n", Status);
  61         NtClose(PhysMemHandle);
  62         return(0);
  63      }
  64    NtClose(PhysMemHandle);
  65    if (BaseAddress != (PVOID)0xa0000)
  66      {
  67        DbgPrint("Couldn't map physical memory at the right address "
  68                 "(was %x)\n", BaseAddress);
  69        return(0);
  70      }
  71
  72    /*
  73     * Map some memory to use for the non-BIOS parts of the v86 mode address
  74     * space
  75     */
  76    BaseAddress = (PVOID)0x1;
  77    ViewSize = 0xa0000 - 0x1000;
  78    Status = ZwAllocateVirtualMemory(NtCurrentProcess(),
  79                                     &BaseAddress,
  80                                     0,
  81                                     &ViewSize,
  82                                     MEM_COMMIT,
  83                                     PAGE_EXECUTE_READWRITE);
  84    if (!NT_SUCCESS(Status))
  85      {
  86        DbgPrint("Failed to allocate virtual memory (Status %x)\n", Status);
  87        return(0);
  88      }
  89    if (BaseAddress != (PVOID)0x0)
  90      {
  91        DbgPrint("Failed to allocate virtual memory at right address "
  92                 "(was %x)\n", BaseAddress);
  93        return(0);
  94      }
  95
  96    /*
  97     * Get the real mode IVT from the kernel
  98     */
  99    Status = NtVdmControl(0, IVT);
 100    if (!NT_SUCCESS(Status))
 101      {
 102        DbgPrint("NtVdmControl failed (status %x)\n", Status);
 103        return(0);
 104      }
 105
 106    /*
 107     * Copy the real mode IVT into the right place
 108     */
 109    NullAddress = (PVOID)0x0; /* Workaround for GCC 3.4 */
 110    memcpy(NullAddress, IVT, 1024);
 111
 112    /*
 113     * Get the BDA from the kernel
 114     */
 115    Status = NtVdmControl(1, BDA);
 116    if (!NT_SUCCESS(Status))
 117      {
 118        DbgPrint("NtVdmControl failed (status %x)\n", Status);
 119        return(0);
 120      }
 121
 122    /*
 123     * Copy the BDA into the right place
 124     */
 125    memcpy((PVOID)0x400, BDA, 256);
 126
 127    return(1);
 128 }
 129
 130
 131 /* EOF */