msdos/dpmi.c

   1 /*
   2  * DPMI 0.9 emulation
   3  *
   4  * Copyright 1995 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include "config.h"
  22 #include "wine/port.h"
  23
  24 #ifdef HAVE_UNISTD_H
  25 # include <unistd.h>
  26 #endif
  27 #include <string.h>
  28
  29 #include "windef.h"
  30 #include "wine/winbase16.h"
  31 #include "miscemu.h"
  32 #include "msdos.h"
  33 #include "task.h"
  34 #include "toolhelp.h"
  35 #include "selectors.h"
  36 #include "callback.h"
  37 #include "wine/debug.h"
  38 #include "stackframe.h"
  39
  40 WINE_DEFAULT_DEBUG_CHANNEL(int31);
  41
  42 #define DOS_GET_DRIVE(reg) ((reg) ? (reg) - 1 : DRIVE_GetCurrentDrive())
  43
  44 void CreateBPB(int drive, BYTE *data, BOOL16 limited);  /* defined in int21.c */
  45
  46 static void* lastvalloced = NULL;
  47
  48
  49 DOSVM_TABLE Dosvm = { NULL, };
  50
  51 static HMODULE DosModule;
  52
  53 /**********************************************************************
  54  *          DPMI_LoadDosSystem
  55  */
  56 BOOL DPMI_LoadDosSystem(void)
  57 {
  58     if (DosModule) return TRUE;
  59     DosModule = LoadLibraryA( "winedos.dll" );
  60     if (!DosModule) {
  61         ERR("could not load winedos.dll, DOS subsystem unavailable\n");
  62         return FALSE;
  63     }
  64 #define GET_ADDR(func)  Dosvm.func = (void *)GetProcAddress(DosModule, #func);
  65
  66     GET_ADDR(LoadDosExe);
  67     GET_ADDR(CallRMInt);
  68     GET_ADDR(CallRMProc);
  69     GET_ADDR(AllocRMCB);
  70     GET_ADDR(FreeRMCB);
  71     GET_ADDR(RawModeSwitch);
  72     GET_ADDR(SetTimer);
  73     GET_ADDR(GetTimer);
  74     GET_ADDR(inport);
  75     GET_ADDR(outport);
  76     GET_ADDR(ASPIHandler);
  77 #undef GET_ADDR
  78     return TRUE;
  79 }
  80
  81 /**********************************************************************
  82  *          DPMI_xalloc
  83  * special virtualalloc, allocates lineary monoton growing memory.
  84  * (the usual VirtualAlloc does not satisfy that restriction)
  85  */
  86 static LPVOID
  87 DPMI_xalloc(int len) {
  88         LPVOID  ret;
  89         LPVOID  oldlastv = lastvalloced;
  90
  91         if (lastvalloced) {
  92                 int     xflag = 0;
  93                 ret = NULL;
  94                 while (!ret) {
  95                         ret=VirtualAlloc(lastvalloced,len,MEM_COMMIT|MEM_RESERVE,PAGE_EXECUTE_READWRITE);
  96                         if (!ret)
  97                                 lastvalloced = (char *) lastvalloced + 0x10000;
  98                         /* we failed to allocate one in the first round.
  99                          * try non-linear
 100                          */
 101                         if (!xflag && (lastvalloced<oldlastv)) { /* wrapped */
 102                                 FIXME("failed to allocate lineary growing memory (%d bytes), using non-linear growing...\n",len);
 103                                 xflag++;
 104                         }
 105                         /* if we even fail to allocate something in the next
 106                          * round, return NULL
 107                          */
 108                         if ((xflag==1) && (lastvalloced >= oldlastv))
 109                                 xflag++;
 110                         if ((xflag==2) && (lastvalloced < oldlastv)) {
 111                                 FIXME("failed to allocate any memory of %d bytes!\n",len);
 112                                 return NULL;
 113                         }
 114                 }
 115         } else
 116                  ret=VirtualAlloc(NULL,len,MEM_COMMIT|MEM_RESERVE,PAGE_EXECUTE_READWRITE);
 117         lastvalloced = (LPVOID)(((DWORD)ret+len+0xffff)&~0xffff);
 118         return ret;
 119 }
 120
 121 static void
 122 DPMI_xfree(LPVOID ptr) {
 123         VirtualFree(ptr,0,MEM_RELEASE);
 124 }
 125
 126 /* FIXME: perhaps we could grow this mapped area... */
 127 static LPVOID
 128 DPMI_xrealloc(LPVOID ptr,DWORD newsize) {
 129         MEMORY_BASIC_INFORMATION        mbi;
 130         LPVOID                          newptr;
 131
 132         newptr = DPMI_xalloc(newsize);
 133         if (ptr) {
 134                 if (!VirtualQuery(ptr,&mbi,sizeof(mbi))) {
 135                         FIXME("realloc of DPMI_xallocd region %p?\n",ptr);
 136                         return NULL;
 137                 }
 138                 if (mbi.State == MEM_FREE) {
 139                         FIXME("realloc of DPMI_xallocd region %p?\n",ptr);
 140                         return NULL;
 141                 }
 142                 /* We do not shrink allocated memory. most reallocs
 143                  * only do grows anyway
 144                  */
 145                 if (newsize<=mbi.RegionSize)
 146                         return ptr;
 147                 memcpy(newptr,ptr,mbi.RegionSize);
 148                 DPMI_xfree(ptr);
 149         }
 150         return newptr;
 151 }
 152
 153 /**********************************************************************
 154  *          CallRMInt
 155  */
 156 static void CallRMInt( CONTEXT86 *context )
 157 {
 158     if (!Dosvm.CallRMInt && !DPMI_LoadDosSystem())
 159     {
 160         ERR("could not setup real-mode calls\n");
 161         return;
 162     }
 163     Dosvm.CallRMInt( context );
 164 }
 165
 166
 167 static void CallRMProc( CONTEXT86 *context, int iret )
 168 {
 169     if (!Dosvm.CallRMProc && !DPMI_LoadDosSystem())
 170     {
 171         ERR("could not setup real-mode calls\n");
 172         return;
 173     }
 174     Dosvm.CallRMProc( context, iret );
 175 }
 176
 177 static void AllocRMCB( CONTEXT86 *context )
 178 {
 179     if (!Dosvm.AllocRMCB && !DPMI_LoadDosSystem())
 180     {
 181         ERR("could not setup real-mode calls\n");
 182         return;
 183     }
 184     Dosvm.AllocRMCB( context );
 185 }
 186
 187 static void FreeRMCB( CONTEXT86 *context )
 188 {
 189     if (!Dosvm.FreeRMCB)  /* cannot have allocated one if dosvm not loaded */
 190     {
 191         SET_LOWORD( context->Eax, 0x8024 ); /* invalid callback address */
 192         SET_CFLAG( context );
 193     }
 194     else Dosvm.FreeRMCB( context );
 195 }
 196
 197 static void RawModeSwitch( CONTEXT86 *context )
 198 {
 199     if (!Dosvm.RawModeSwitch)
 200     {
 201       ERR("could not setup real-mode calls\n");
 202       return;
 203     }
 204     else
 205     {
 206       /*
 207        * FIXME: This routine will not work if it is called
 208        *        from 32 bit DPMI program and the program returns
 209        *        to protected mode while ESP or EIP is over 0xffff.
 210        * FIXME: This routine will not work if it is not called
 211        *        using 16-bit-to-Wine callback glue function.
 212        */
 213       STACK16FRAME frame = *CURRENT_STACK16;
 214
 215       Dosvm.RawModeSwitch( context );
 216
 217       /*
 218        * After this function returns to relay code, protected mode
 219        * 16 bit stack will contain STACK16FRAME and single WORD
 220        * (EFlags, see next comment).
 221        */
 222       NtCurrentTeb()->cur_stack =
 223         MAKESEGPTR( context->SegSs,
 224                     context->Esp - sizeof(STACK16FRAME) - sizeof(WORD) );
 225
 226       /*
 227        * After relay code returns to glue function, protected
 228        * mode 16 bit stack will contain interrupt return record:
 229        * IP, CS and EFlags. Since EFlags is ignored, it won't
 230        * need to be initialized.
 231        */
 232       context->Esp -= 3 * sizeof(WORD);
 233
 234       /*
 235        * Restore stack frame so that relay code won't be confused.
 236        * It should be noted that relay code overwrites IP and CS
 237        * in STACK16FRAME with values taken from current CONTEXT86.
 238        * These values are what is returned to glue function
 239        * (see previous comment).
 240        */
 241       *CURRENT_STACK16 = frame;
 242     }
 243 }
 244
 245 /**********************************************************************
 246  *          INT_Int31Handler (WPROCS.149)
 247  *
 248  * Handler for int 31h (DPMI).
 249  */
 250
 251 void WINAPI INT_Int31Handler( CONTEXT86 *context )
 252 {
 253     /*
 254      * Note: For Win32s processes, the whole linear address space is
 255      *       shifted by 0x10000 relative to the OS linear address space.
 256      *       See the comment in msdos/vxd.c.
 257      */
 258     DWORD dw;
 259     BYTE *ptr;
 260
 261     if (context->SegCs == DOSMEM_dpmi_sel) {
 262         RawModeSwitch( context );
 263         return;
 264     }
 265
 266     RESET_CFLAG(context);
 267     switch(AX_reg(context))
 268     {
 269     case 0x0000:  /* Allocate LDT descriptors */
 270         TRACE("allocate LDT descriptors (%d)\n",CX_reg(context));
 271         if (!(context->Eax = AllocSelectorArray16( CX_reg(context) )))
 272         {
 273             TRACE("failed\n");
 274             context->Eax = 0x8011;  /* descriptor unavailable */
 275             SET_CFLAG(context);
 276         }
 277         TRACE("success, array starts at 0x%04x\n",AX_reg(context));
 278         break;
 279
 280     case 0x0001:  /* Free LDT descriptor */
 281         TRACE("free LDT descriptor (0x%04x)\n",BX_reg(context));
 282         if (FreeSelector16( BX_reg(context) ))
 283         {
 284             context->Eax = 0x8022;  /* invalid selector */
 285             SET_CFLAG(context);
 286         }
 287         else
 288         {
 289             /* If a segment register contains the selector being freed, */
 290             /* set it to zero. */
 291             if (!((context->SegDs^BX_reg(context)) & ~3)) context->SegDs = 0;
 292             if (!((context->SegEs^BX_reg(context)) & ~3)) context->SegEs = 0;
 293             if (!((context->SegFs^BX_reg(context)) & ~3)) context->SegFs = 0;
 294             if (!((context->SegGs^BX_reg(context)) & ~3)) context->SegGs = 0;
 295         }
 296         break;
 297
 298     case 0x0002:  /* Real mode segment to descriptor */
 299         TRACE("real mode segment to descriptor (0x%04x)\n",BX_reg(context));
 300         {
 301             WORD entryPoint = 0;  /* KERNEL entry point for descriptor */
 302             switch(BX_reg(context))
 303             {
 304             case 0x0000: entryPoint = 183; break;  /* __0000H */
 305             case 0x0040: entryPoint = 193; break;  /* __0040H */
 306             case 0xa000: entryPoint = 174; break;  /* __A000H */
 307             case 0xb000: entryPoint = 181; break;  /* __B000H */
 308             case 0xb800: entryPoint = 182; break;  /* __B800H */
 309             case 0xc000: entryPoint = 195; break;  /* __C000H */
 310             case 0xd000: entryPoint = 179; break;  /* __D000H */
 311             case 0xe000: entryPoint = 190; break;  /* __E000H */
 312             case 0xf000: entryPoint = 194; break;  /* __F000H */
 313             default:
 314                 context->Eax = DOSMEM_AllocSelector(BX_reg(context));
 315                 break;
 316             }
 317             if (entryPoint)
 318                 context->Eax = LOWORD(GetProcAddress16( GetModuleHandle16( "KERNEL" ),
 319                                                         (LPCSTR)(ULONG_PTR)entryPoint ));
 320         }
 321         break;
 322
 323     case 0x0003:  /* Get next selector increment */
 324         TRACE("get selector increment (__AHINCR)\n");
 325         context->Eax = __AHINCR;
 326         break;
 327
 328     case 0x0004:  /* Lock selector (not supported) */
 329         FIXME("lock selector not supported\n");
 330         context->Eax = 0;  /* FIXME: is this a correct return value? */
 331         break;
 332
 333     case 0x0005:  /* Unlock selector (not supported) */
 334         FIXME("unlock selector not supported\n");
 335         context->Eax = 0;  /* FIXME: is this a correct return value? */
 336         break;
 337
 338     case 0x0006:  /* Get selector base address */
 339         TRACE("get selector base address (0x%04x)\n",BX_reg(context));
 340         if (!(dw = GetSelectorBase( BX_reg(context) )))
 341         {
 342             context->Eax = 0x8022;  /* invalid selector */
 343             SET_CFLAG(context);
 344         }
 345         else
 346         {
 347             CX_reg(context) = HIWORD(W32S_WINE2APP(dw));
 348             DX_reg(context) = LOWORD(W32S_WINE2APP(dw));
 349         }
 350         break;
 351
 352     case 0x0007:  /* Set selector base address */
 353         TRACE("set selector base address (0x%04x,0x%08lx)\n",
 354                      BX_reg(context),
 355                      W32S_APP2WINE(MAKELONG(DX_reg(context),CX_reg(context))));
 356         dw = W32S_APP2WINE(MAKELONG(DX_reg(context), CX_reg(context)));
 357         if (dw < 0x10000)
 358             /* app wants to access lower 64K of DOS memory, load DOS subsystem */
 359             DPMI_LoadDosSystem();
 360         SetSelectorBase(BX_reg(context), dw);
 361         break;
 362
 363     case 0x0008:  /* Set selector limit */
 364         TRACE("set selector limit (0x%04x,0x%08lx)\n",BX_reg(context),MAKELONG(DX_reg(context),CX_reg(context)));
 365         dw = MAKELONG( DX_reg(context), CX_reg(context) );
 366         SetSelectorLimit16( BX_reg(context), dw );
 367         break;
 368
 369     case 0x0009:  /* Set selector access rights */
 370         TRACE("set selector access rights(0x%04x,0x%04x)\n",BX_reg(context),CX_reg(context));
 371         SelectorAccessRights16( BX_reg(context), 1, CX_reg(context) );
 372         break;
 373
 374     case 0x000a:  /* Allocate selector alias */
 375         TRACE("allocate selector alias (0x%04x)\n",BX_reg(context));
 376         if (!(AX_reg(context) = AllocCStoDSAlias16( BX_reg(context) )))
 377         {
 378             AX_reg(context) = 0x8011;  /* descriptor unavailable */
 379             SET_CFLAG(context);
 380         }
 381         break;
 382
 383     case 0x000b:  /* Get descriptor */
 384         TRACE("get descriptor (0x%04x)\n",BX_reg(context));
 385         {
 386             LDT_ENTRY entry;
 387             wine_ldt_set_base( &entry, (void*)W32S_WINE2APP(wine_ldt_get_base(&entry)) );
 388             /* FIXME: should use ES:EDI for 32-bit clients */
 389             *(LDT_ENTRY *)MapSL( MAKESEGPTR( context->SegEs, LOWORD(context->Edi) )) = entry;
 390         }
 391         break;
 392
 393     case 0x000c:  /* Set descriptor */
 394         TRACE("set descriptor (0x%04x)\n",BX_reg(context));
 395         {
 396             LDT_ENTRY entry = *(LDT_ENTRY *)MapSL(MAKESEGPTR( context->SegEs, LOWORD(context->Edi)));
 397             wine_ldt_set_base( &entry, (void*)W32S_APP2WINE(wine_ldt_get_base(&entry)) );
 398             wine_ldt_set_entry( LOWORD(context->Ebx), &entry );
 399         }
 400         break;
 401
 402     case 0x000d:  /* Allocate specific LDT descriptor */
 403         FIXME("allocate descriptor (0x%04x), stub!\n",BX_reg(context));
 404         AX_reg(context) = 0x8011; /* descriptor unavailable */
 405         SET_CFLAG(context);
 406         break;
 407     case 0x0100:  /* Allocate DOS memory block */
 408         TRACE("allocate DOS memory block (0x%x paragraphs)\n",BX_reg(context));
 409         dw = GlobalDOSAlloc16((DWORD)BX_reg(context)<<4);
 410         if (dw) {
 411             AX_reg(context) = HIWORD(dw);
 412             DX_reg(context) = LOWORD(dw);
 413         } else {
 414             AX_reg(context) = 0x0008; /* insufficient memory */
 415             BX_reg(context) = DOSMEM_Available()>>4;
 416             SET_CFLAG(context);
 417         }
 418         break;
 419     case 0x0101:  /* Free DOS memory block */
 420         TRACE("free DOS memory block (0x%04x)\n",DX_reg(context));
 421         dw = GlobalDOSFree16(DX_reg(context));
 422         if (!dw) {
 423             AX_reg(context) = 0x0009; /* memory block address invalid */
 424             SET_CFLAG(context);
 425         }
 426         break;
 427     case 0x0200: /* get real mode interrupt vector */
 428         FIXME("get realmode interupt vector(0x%02x) unimplemented.\n",
 429               BL_reg(context));
 430         SET_CFLAG(context);
 431         break;
 432     case 0x0201: /* set real mode interrupt vector */
 433         FIXME("set realmode interrupt vector(0x%02x,0x%04x:0x%04x) unimplemented\n", BL_reg(context),CX_reg(context),DX_reg(context));
 434         SET_CFLAG(context);
 435         break;
 436     case 0x0204:  /* Get protected mode interrupt vector */
 437         TRACE("get protected mode interrupt handler (0x%02x), stub!\n",BL_reg(context));
 438         dw = (DWORD)INT_GetPMHandler( BL_reg(context) );
 439         CX_reg(context) = HIWORD(dw);
 440         DX_reg(context) = LOWORD(dw);
 441         break;
 442
 443     case 0x0205:  /* Set protected mode interrupt vector */
 444         TRACE("set protected mode interrupt handler (0x%02x,%p), stub!\n",
 445             BL_reg(context),MapSL(MAKESEGPTR(CX_reg(context),DX_reg(context))));
 446         INT_SetPMHandler( BL_reg(context),
 447                           (FARPROC16)MAKESEGPTR( CX_reg(context), DX_reg(context) ));
 448         break;
 449
 450     case 0x0300:  /* Simulate real mode interrupt */
 451         CallRMInt( context );
 452         break;
 453
 454     case 0x0301:  /* Call real mode procedure with far return */
 455         CallRMProc( context, FALSE );
 456         break;
 457
 458     case 0x0302:  /* Call real mode procedure with interrupt return */
 459         CallRMProc( context, TRUE );
 460         break;
 461
 462     case 0x0303:  /* Allocate Real Mode Callback Address */
 463         AllocRMCB( context );
 464         break;
 465
 466     case 0x0304:  /* Free Real Mode Callback Address */
 467         FreeRMCB( context );
 468         break;
 469
 470     case 0x0305:  /* Get State Save/Restore Addresses */
 471         TRACE("get state save/restore addresses\n");
 472         /* we probably won't need this kind of state saving */
 473         AX_reg(context) = 0;
 474         /* real mode: just point to the lret */
 475         BX_reg(context) = DOSMEM_wrap_seg;
 476         context->Ecx = 2;
 477         /* protected mode: don't have any handler yet... */
 478         FIXME("no protected-mode dummy state save/restore handler yet\n");
 479         SI_reg(context) = 0;
 480         context->Edi = 0;
 481         break;
 482
 483     case 0x0306:  /* Get Raw Mode Switch Addresses */
 484         TRACE("get raw mode switch addresses\n");
 485         /* real mode, point to standard DPMI return wrapper */
 486         BX_reg(context) = DOSMEM_wrap_seg;
 487         context->Ecx = 0;
 488         /* protected mode, point to DPMI call wrapper */
 489         SI_reg(context) = DOSMEM_dpmi_sel;
 490         context->Edi = 8; /* offset of the INT 0x31 call */
 491         break;
 492     case 0x0400:  /* Get DPMI version */
 493         TRACE("get DPMI version\n");
 494         {
 495             SYSTEM_INFO si;
 496
 497             GetSystemInfo(&si);
 498             AX_reg(context) = 0x005a;  /* DPMI version 0.90 */
 499             BX_reg(context) = 0x0005;  /* Flags: 32-bit, virtual memory */
 500             CL_reg(context) = si.wProcessorLevel;
 501             DX_reg(context) = 0x0102;  /* Master/slave interrupt controller base*/
 502             break;
 503         }
 504     case 0x0500:  /* Get free memory information */
 505         TRACE("get free memory information\n");
 506         {
 507             MEMMANINFO mmi;
 508
 509             mmi.dwSize = sizeof(mmi);
 510             MemManInfo16(&mmi);
 511             ptr = MapSL(MAKESEGPTR(context->SegEs,DI_reg(context)));
 512             /* the layout is just the same as MEMMANINFO, but without
 513              * the dwSize entry.
 514              */
 515             memcpy(ptr,((char*)&mmi)+4,sizeof(mmi)-4);
 516             break;
 517         }
 518     case 0x0501:  /* Allocate memory block */
 519         TRACE("allocate memory block (%ld)\n",MAKELONG(CX_reg(context),BX_reg(context)));
 520         if (!(ptr = (BYTE *)DPMI_xalloc(MAKELONG(CX_reg(context), BX_reg(context)))))
 521         {
 522             AX_reg(context) = 0x8012;  /* linear memory not available */
 523             SET_CFLAG(context);
 524         } else {
 525             BX_reg(context) = SI_reg(context) = HIWORD(W32S_WINE2APP(ptr));
 526             CX_reg(context) = DI_reg(context) = LOWORD(W32S_WINE2APP(ptr));
 527         }
 528         break;
 529
 530     case 0x0502:  /* Free memory block */
 531         TRACE("free memory block (0x%08lx)\n",
 532                      W32S_APP2WINE(MAKELONG(DI_reg(context),SI_reg(context))));
 533         DPMI_xfree( (void *)W32S_APP2WINE(MAKELONG(DI_reg(context), SI_reg(context))) );
 534         break;
 535
 536     case 0x0503:  /* Resize memory block */
 537         TRACE("resize memory block (0x%08lx,%ld)\n",
 538                      W32S_APP2WINE(MAKELONG(DI_reg(context),SI_reg(context))),
 539                      MAKELONG(CX_reg(context),BX_reg(context)));
 540         if (!(ptr = (BYTE *)DPMI_xrealloc(
 541                 (void *)W32S_APP2WINE(MAKELONG(DI_reg(context),SI_reg(context))),
 542                 MAKELONG(CX_reg(context),BX_reg(context)))))
 543         {
 544             AX_reg(context) = 0x8012;  /* linear memory not available */
 545             SET_CFLAG(context);
 546         } else {
 547             BX_reg(context) = SI_reg(context) = HIWORD(W32S_WINE2APP(ptr));
 548             CX_reg(context) = DI_reg(context) = LOWORD(W32S_WINE2APP(ptr));
 549         }
 550         break;
 551
 552     case 0x0507:  /* Modify page attributes */
 553         FIXME("modify page attributes unimplemented\n");
 554         break;  /* Just ignore it */
 555
 556     case 0x0600:  /* Lock linear region */
 557         FIXME("lock linear region unimplemented\n");
 558         break;  /* Just ignore it */
 559
 560     case 0x0601:  /* Unlock linear region */
 561         FIXME("unlock linear region unimplemented\n");
 562         break;  /* Just ignore it */
 563
 564     case 0x0602:  /* Unlock real-mode region */
 565         FIXME("unlock realmode region unimplemented\n");
 566         break;  /* Just ignore it */
 567
 568     case 0x0603:  /* Lock real-mode region */
 569         FIXME("lock realmode region unimplemented\n");
 570         break;  /* Just ignore it */
 571
 572     case 0x0604:  /* Get page size */
 573         TRACE("get pagesize\n");
 574         BX_reg(context) = 0;
 575         CX_reg(context) = getpagesize();
 576         break;
 577
 578     case 0x0702:  /* Mark page as demand-paging candidate */
 579         FIXME("mark page as demand-paging candidate\n");
 580         break;  /* Just ignore it */
 581
 582     case 0x0703:  /* Discard page contents */
 583         FIXME("discard page contents\n");
 584         break;  /* Just ignore it */
 585
 586      case 0x0800:  /* Physical address mapping */
 587         FIXME("map real to linear (0x%08lx)\n",MAKELONG(CX_reg(context),BX_reg(context)));
 588          if(!(ptr=DOSMEM_MapRealToLinear(MAKELONG(CX_reg(context),BX_reg(context)))))
 589          {
 590              AX_reg(context) = 0x8021;
 591              SET_CFLAG(context);
 592          }
 593          else
 594          {
 595              BX_reg(context) = HIWORD(W32S_WINE2APP(ptr));
 596              CX_reg(context) = LOWORD(W32S_WINE2APP(ptr));
 597              RESET_CFLAG(context);
 598          }
 599          break;
 600
 601     default:
 602         INT_BARF( context, 0x31 );
 603         AX_reg(context) = 0x8001;  /* unsupported function */
 604         SET_CFLAG(context);
 605         break;
 606     }
 607
 608 }