msdos/dpmi.c

   1 /*
   2  * DPMI 0.9 emulation
   3  *
   4  * Copyright 1995 Alexandre Julliard
   5  */
   6
   7 #include <unistd.h>
   8 #include <string.h>
   9 #include "windows.h"
  10 #include "heap.h"
  11 #include "ldt.h"
  12 #include "module.h"
  13 #include "miscemu.h"
  14 #include "drive.h"
  15 #include "msdos.h"
  16 #include "toolhelp.h"
  17 #include "debug.h"
  18 #include "selectors.h"
  19 #include "thread.h"
  20 #include "stackframe.h"
  21 #include "callback.h"
  22
  23 #define DOS_GET_DRIVE(reg) ((reg) ? (reg) - 1 : DRIVE_GetCurrentDrive())
  24
  25 void CreateBPB(int drive, BYTE *data, BOOL16 limited);  /* defined in int21.c */
  26
  27
  28 /* Structure for real-mode callbacks */
  29 typedef struct
  30 {
  31     DWORD edi;
  32     DWORD esi;
  33     DWORD ebp;
  34     DWORD reserved;
  35     DWORD ebx;
  36     DWORD edx;
  37     DWORD ecx;
  38     DWORD eax;
  39     WORD  fl;
  40     WORD  es;
  41     WORD  ds;
  42     WORD  fs;
  43     WORD  gs;
  44     WORD  ip;
  45     WORD  cs;
  46     WORD  sp;
  47     WORD  ss;
  48 } REALMODECALL;
  49
  50
  51
  52 typedef struct tagRMCB {
  53     DWORD address;
  54     struct tagRMCB *next;
  55
  56 } RMCB;
  57
  58 static RMCB *FirstRMCB = NULL;
  59
  60 /**********************************************************************
  61  *          INT_GetRealModeContext
  62  */
  63 static void INT_GetRealModeContext( REALMODECALL *call, CONTEXT *context )
  64 {
  65     EAX_reg(context) = call->eax;
  66     EBX_reg(context) = call->ebx;
  67     ECX_reg(context) = call->ecx;
  68     EDX_reg(context) = call->edx;
  69     ESI_reg(context) = call->esi;
  70     EDI_reg(context) = call->edi;
  71     EBP_reg(context) = call->ebp;
  72     EFL_reg(context) = call->fl;
  73     EIP_reg(context) = call->ip;
  74     ESP_reg(context) = call->sp;
  75     CS_reg(context)  = call->cs;
  76     DS_reg(context)  = call->ds;
  77     ES_reg(context)  = call->es;
  78     FS_reg(context)  = call->fs;
  79     GS_reg(context)  = call->gs;
  80 }
  81
  82
  83 /**********************************************************************
  84  *          INT_SetRealModeContext
  85  */
  86 static void INT_SetRealModeContext( REALMODECALL *call, CONTEXT *context )
  87 {
  88     call->eax = EAX_reg(context);
  89     call->ebx = EBX_reg(context);
  90     call->ecx = ECX_reg(context);
  91     call->edx = EDX_reg(context);
  92     call->esi = ESI_reg(context);
  93     call->edi = EDI_reg(context);
  94     call->ebp = EBP_reg(context);
  95     call->fl  = FL_reg(context);
  96     call->ip  = IP_reg(context);
  97     call->sp  = SP_reg(context);
  98     call->cs  = CS_reg(context);
  99     call->ds  = DS_reg(context);
 100     call->es  = ES_reg(context);
 101     call->fs  = FS_reg(context);
 102     call->gs  = GS_reg(context);
 103 }
 104
 105
 106 /**********************************************************************
 107  *          INT_DoRealModeInt
 108  */
 109 static void INT_DoRealModeInt( CONTEXT *context )
 110 {
 111     CONTEXT realmode_ctx;
 112     REALMODECALL *call = (REALMODECALL *)PTR_SEG_OFF_TO_LIN( ES_reg(context),
 113                                                           DI_reg(context) );
 114     INT_GetRealModeContext( call, &realmode_ctx );
 115
 116     RESET_CFLAG(context);
 117     switch (BL_reg(context))
 118     {
 119     case 0x2f:  /* int2f */
 120         switch (AH_reg(&realmode_ctx))
 121         {
 122         case 0x15:
 123             /* MSCDEX hook */
 124             do_mscdex( &realmode_ctx );
 125             break;
 126         default:
 127             SET_CFLAG(context);
 128             break;
 129         }
 130         break;
 131     case 0x21:  /* int21 */
 132         switch (AH_reg(&realmode_ctx))
 133         {
 134         case 0x52:
 135             ES_reg(&realmode_ctx) = 0;
 136             EBX_reg(&realmode_ctx) = 0;
 137             break;
 138         case 0x65:
 139             switch (AL_reg(&realmode_ctx))
 140             {
 141             case 0x06:
 142                 {/* get collate table */
 143                     /* ES:DI is a REALMODE pointer to 5 byte dosmem
 144                      * we fill that with 0x6, realmode pointer to collateTB
 145                      */
 146                     char *table = DOSMEM_MapRealToLinear(
 147                        MAKELONG(EDI_reg(&realmode_ctx),ES_reg(&realmode_ctx)));
 148                     *(BYTE*)table      = 0x06;
 149                     *(DWORD*)(table+1) = DOSMEM_CollateTable;
 150                     CX_reg(&realmode_ctx) = 258;/*FIXME: size of table?*/
 151                     break;
 152                 }
 153             default:
 154                 SET_CFLAG(context);
 155                 break;
 156             }
 157             break;
 158         case 0x44:
 159             switch (AL_reg(&realmode_ctx))
 160             {
 161             case 0x0D:
 162                 {/* generic block device request */
 163                     BYTE *dataptr = DOSMEM_MapRealToLinear(
 164                        MAKELONG(EDX_reg(&realmode_ctx),DS_reg(&realmode_ctx)));
 165                     int drive = DOS_GET_DRIVE(BL_reg(&realmode_ctx));
 166                     if (CH_reg(&realmode_ctx) != 0x08)
 167                     {
 168                         SET_CFLAG(context);
 169                         break;
 170                     }
 171                     switch (CL_reg(&realmode_ctx))
 172                     {
 173                     case 0x66:
 174                         {
 175                             char    label[12],fsname[9],path[4];
 176                             DWORD   serial;
 177
 178                             strcpy(path,"x:\\");path[0]=drive+'A';
 179                             GetVolumeInformation32A(path,label,12,&serial,NULL,NULL,fsname,9);
 180                             *(WORD*)dataptr         = 0;
 181                             memcpy(dataptr+2,&serial,4);
 182                             memcpy(dataptr+6,label  ,11);
 183                             memcpy(dataptr+17,fsname,8);
 184                             break;
 185                         }
 186                     case 0x60:  /* get device parameters */
 187                                 /* used by defrag.exe of win95 */
 188                         memset(dataptr, 0, 0x26);
 189                         dataptr[0] = 0x04;
 190                         dataptr[6] = 0; /* media type */
 191                         if (drive > 1)
 192                         {
 193                             dataptr[1] = 0x05; /* fixed disk */
 194                             setword(&dataptr[2], 0x01); /* non removable */
 195                             setword(&dataptr[4], 0x300); /* # of cylinders */
 196                         }
 197                         else
 198                         {
 199                             dataptr[1] = 0x07; /* block dev, floppy */
 200                             setword(&dataptr[2], 0x02); /* removable */
 201                             setword(&dataptr[4], 80); /* # of cylinders */
 202                         }
 203                         CreateBPB(drive, &dataptr[7], FALSE);
 204                         break;
 205                     default:
 206                         SET_CFLAG(context);
 207                         break;
 208                     }
 209                 }
 210             break;
 211             default:
 212                 SET_CFLAG(context);
 213                 break;
 214             }
 215             break;
 216         default:
 217             SET_CFLAG(context);
 218             break;
 219         }
 220         break;
 221     default:
 222         SET_CFLAG(context);
 223         break;
 224     }
 225
 226     if (EFL_reg(context)&1) {
 227       FIXME(int31,"%02x: EAX=%08lx EBX=%08lx ECX=%08lx EDX=%08lx\n",
 228             BL_reg(context), EAX_reg(&realmode_ctx), EBX_reg(&realmode_ctx),
 229             ECX_reg(&realmode_ctx), EDX_reg(&realmode_ctx));
 230       FIXME(int31,"      ESI=%08lx EDI=%08lx DS=%04lx ES=%04lx\n",
 231             ESI_reg(&realmode_ctx), EDI_reg(&realmode_ctx),
 232             DS_reg(&realmode_ctx), ES_reg(&realmode_ctx) );
 233     }
 234     INT_SetRealModeContext( call, &realmode_ctx );
 235 }
 236
 237
 238 static void CallRMProcFar( CONTEXT *context )
 239 {
 240     REALMODECALL *p = (REALMODECALL *)PTR_SEG_OFF_TO_LIN( ES_reg(context), DI_reg(context) );
 241     CONTEXT context16;
 242     THDB *thdb = THREAD_Current();
 243     WORD argsize, sel;
 244     LPVOID addr;
 245     SEGPTR seg_addr;
 246
 247     TRACE(int31, "RealModeCall: EAX=%08lx EBX=%08lx ECX=%08lx EDX=%08lx\n",
 248         p->eax, p->ebx, p->ecx, p->edx);
 249     TRACE(int31, "              ESI=%08lx EDI=%08lx ES=%04x DS=%04x CS:IP=%04x:%04x, %d WORD arguments\n",
 250         p->esi, p->edi, p->es, p->ds, p->cs, p->ip, CX_reg(context) );
 251
 252     if (!(p->cs) && !(p->ip)) { /* remove this check
 253                                    if Int21/6501 case map function
 254                                    has been implemented */
 255         SET_CFLAG(context);
 256         return;
 257     }
 258     INT_GetRealModeContext(p, &context16);
 259
 260     addr = DOSMEM_MapRealToLinear(MAKELONG(p->ip, p->cs));
 261     sel = SELECTOR_AllocBlock( addr, 0x10000, SEGMENT_CODE, FALSE, FALSE );
 262     seg_addr = PTR_SEG_OFF_TO_SEGPTR( sel, 0 );
 263
 264     CS_reg(&context16) = HIWORD(seg_addr);
 265     IP_reg(&context16) = LOWORD(seg_addr);
 266     EBP_reg(&context16) = OFFSETOF( thdb->cur_stack )
 267                                + (WORD)&((STACK16FRAME*)0)->bp;
 268
 269     argsize = CX_reg(context)*sizeof(WORD);
 270     memcpy( ((LPBYTE)THREAD_STACK16(thdb))-argsize,
 271     (LPBYTE)PTR_SEG_OFF_TO_LIN(SS_reg(context), SP_reg(context))+6, argsize );
 272
 273     Callbacks->CallRegisterShortProc(&context16, argsize);
 274
 275     UnMapLS(seg_addr);
 276     INT_SetRealModeContext(p, &context16);
 277 }
 278
 279
 280 void WINAPI RMCallbackProc( FARPROC16 pmProc, REALMODECALL *rmc )
 281 {
 282     CONTEXT ctx;
 283     INT_GetRealModeContext(rmc, &ctx);
 284     Callbacks->CallRegisterShortProc(&ctx, 0);
 285 }
 286
 287
 288 static void AllocRMCB( CONTEXT *context )
 289 {
 290     RMCB *NewRMCB = HeapAlloc(GetProcessHeap(), 0, sizeof(RMCB));
 291     REALMODECALL *p = (REALMODECALL *)PTR_SEG_OFF_TO_LIN( ES_reg(context), DI_reg(context) );
 292     UINT16 uParagraph;
 293
 294     FIXME(int31, "EAX=%08lx EBX=%08lx ECX=%08lx EDX=%08lx\n", p->eax, p->ebx, p->ecx, p->edx);
 295     FIXME(int31, "           ESI=%08lx EDI=%08lx ES=%04x DS=%04x CS:IP=%04x:%04x\n", p->esi, p->edi, p->es, p->ds, p->cs, p->ip);
 296     FIXME(int31, "           Function to call: %04x:%04x\n",
 297          (WORD)DS_reg(context), SI_reg(context) );
 298
 299     if (NewRMCB)
 300     {
 301         LPVOID RMCBmem = DOSMEM_GetBlock(20, &uParagraph);
 302         LPBYTE p = RMCBmem;
 303
 304         *p++ = 0x68; /* pushl */
 305         *(FARPROC16 *)p =
 306         PTR_SEG_OFF_TO_LIN(ES_reg(context), SI_reg(context)); /* pmode proc to call */
 307         p+=4;
 308         *p++ = 0x68; /* pushl */
 309         *(LPVOID *)p =
 310         PTR_SEG_OFF_TO_LIN(ES_reg(context), DI_reg(context));
 311         p+=4;
 312         *p++ = 0x9a; /* lcall */
 313         *(FARPROC16 *)p = (FARPROC16)RMCallbackProc; /* FIXME ? */
 314         p+=4;
 315         GET_CS(*(WORD *)p);
 316         p+=2;
 317         *p++=0xc3; /* retf */
 318         NewRMCB->address = MAKELONG(0, uParagraph);
 319         NewRMCB->next = FirstRMCB;
 320         FirstRMCB = NewRMCB;
 321         CX_reg(context) = uParagraph;
 322         DX_reg(context) = 0;
 323     }
 324     else
 325     {
 326         AX_reg(context) = 0x8015; /* callback unavailable */
 327         SET_CFLAG(context);
 328     }
 329 }
 330
 331
 332 static void FreeRMCB( CONTEXT *context )
 333 {
 334     RMCB *CurrRMCB = FirstRMCB;
 335     RMCB *PrevRMCB = NULL;
 336
 337     FIXME(int31, "callback address: %04x:%04x\n",
 338           CX_reg(context), DX_reg(context));
 339
 340     while (CurrRMCB && (CurrRMCB->address != MAKELONG(DX_reg(context), CX_reg(context))))
 341     {
 342         PrevRMCB = CurrRMCB;
 343         CurrRMCB = CurrRMCB->next;
 344     }
 345     if (CurrRMCB)
 346     {
 347         if (PrevRMCB)
 348         PrevRMCB->next = CurrRMCB->next;
 349             else
 350         FirstRMCB = CurrRMCB->next;
 351         DOSMEM_FreeBlock(DOSMEM_MapRealToLinear(CurrRMCB->address));
 352         HeapFree(GetProcessHeap(), 0, CurrRMCB);
 353     }
 354     else
 355     {
 356         AX_reg(context) = 0x8024; /* invalid callback address */
 357         SET_CFLAG(context);
 358     }
 359 }
 360
 361
 362 /**********************************************************************
 363  *          INT_Int31Handler
 364  *
 365  * Handler for int 31h (DPMI).
 366  */
 367 void WINAPI INT_Int31Handler( CONTEXT *context )
 368 {
 369     DWORD dw;
 370     BYTE *ptr;
 371
 372     RESET_CFLAG(context);
 373     switch(AX_reg(context))
 374     {
 375     case 0x0000:  /* Allocate LDT descriptors */
 376         TRACE(int31,"allocate LDT descriptors (%d)\n",CX_reg(context));
 377         if (!(AX_reg(context) = AllocSelectorArray( CX_reg(context) )))
 378         {
 379             TRACE(int31,"failed\n");
 380             AX_reg(context) = 0x8011;  /* descriptor unavailable */
 381             SET_CFLAG(context);
 382         }
 383         TRACE(int31,"success, array starts at 0x%04x\n",AX_reg(context));
 384         break;
 385
 386     case 0x0001:  /* Free LDT descriptor */
 387         TRACE(int31,"free LDT descriptor (0x%04x)\n",BX_reg(context));
 388         if (FreeSelector( BX_reg(context) ))
 389         {
 390             AX_reg(context) = 0x8022;  /* invalid selector */
 391             SET_CFLAG(context);
 392         }
 393         else
 394         {
 395             /* If a segment register contains the selector being freed, */
 396             /* set it to zero. */
 397             if (!((DS_reg(context)^BX_reg(context)) & ~3)) DS_reg(context) = 0;
 398             if (!((ES_reg(context)^BX_reg(context)) & ~3)) ES_reg(context) = 0;
 399             if (!((FS_reg(context)^BX_reg(context)) & ~3)) FS_reg(context) = 0;
 400             if (!((GS_reg(context)^BX_reg(context)) & ~3)) GS_reg(context) = 0;
 401         }
 402         break;
 403
 404     case 0x0002:  /* Real mode segment to descriptor */
 405         TRACE(int31,"real mode segment to descriptor (0x%04x)\n",BX_reg(context));
 406         {
 407             WORD entryPoint = 0;  /* KERNEL entry point for descriptor */
 408             switch(BX_reg(context))
 409             {
 410             case 0x0000: entryPoint = 183; break;  /* __0000H */
 411             case 0x0040: entryPoint = 193; break;  /* __0040H */
 412             case 0xa000: entryPoint = 174; break;  /* __A000H */
 413             case 0xb000: entryPoint = 181; break;  /* __B000H */
 414             case 0xb800: entryPoint = 182; break;  /* __B800H */
 415             case 0xc000: entryPoint = 195; break;  /* __C000H */
 416             case 0xd000: entryPoint = 179; break;  /* __D000H */
 417             case 0xe000: entryPoint = 190; break;  /* __E000H */
 418             case 0xf000: entryPoint = 194; break;  /* __F000H */
 419             default:
 420                 AX_reg(context) = DOSMEM_AllocSelector(BX_reg(context));
 421                 break;
 422             }
 423             if (entryPoint)
 424                 AX_reg(context) = LOWORD(NE_GetEntryPoint(
 425                                                  GetModuleHandle16( "KERNEL" ),
 426                                                  entryPoint ));
 427         }
 428         break;
 429
 430     case 0x0003:  /* Get next selector increment */
 431         TRACE(int31,"get selector increment (__AHINCR)\n");
 432         AX_reg(context) = __AHINCR;
 433         break;
 434
 435     case 0x0004:  /* Lock selector (not supported) */
 436         FIXME(int31,"lock selector not supported\n");
 437         AX_reg(context) = 0;  /* FIXME: is this a correct return value? */
 438         break;
 439
 440     case 0x0005:  /* Unlock selector (not supported) */
 441         FIXME(int31,"unlock selector not supported\n");
 442         AX_reg(context) = 0;  /* FIXME: is this a correct return value? */
 443         break;
 444
 445     case 0x0006:  /* Get selector base address */
 446         TRACE(int31,"get selector base address (0x%04x)\n",BX_reg(context));
 447         if (!(dw = GetSelectorBase( BX_reg(context) )))
 448         {
 449             AX_reg(context) = 0x8022;  /* invalid selector */
 450             SET_CFLAG(context);
 451         }
 452         else
 453         {
 454             CX_reg(context) = HIWORD(dw);
 455             DX_reg(context) = LOWORD(dw);
 456         }
 457         break;
 458
 459     case 0x0007:  /* Set selector base address */
 460         TRACE(int31,"set selector base address (0x%04x,0x%08lx)\n",BX_reg(context),MAKELONG(DX_reg(context),CX_reg(context)));
 461         SetSelectorBase( BX_reg(context),
 462                          MAKELONG( DX_reg(context), CX_reg(context) ) );
 463         break;
 464
 465     case 0x0008:  /* Set selector limit */
 466         TRACE(int31,"set selector limit (0x%04x,0x%08lx)\n",BX_reg(context),MAKELONG(DX_reg(context),CX_reg(context)));
 467         SetSelectorLimit( BX_reg(context),
 468                           MAKELONG( DX_reg(context), CX_reg(context) ) );
 469         break;
 470
 471     case 0x0009:  /* Set selector access rights */
 472         TRACE(int31,"set selector access rights(0x%04x,0x%04x)\n",BX_reg(context),CX_reg(context));
 473         SelectorAccessRights( BX_reg(context), 1, CX_reg(context) );
 474         break;
 475
 476     case 0x000a:  /* Allocate selector alias */
 477         TRACE(int31,"allocate selector alias (0x%04x)\n",BX_reg(context));
 478         if (!(AX_reg(context) = AllocCStoDSAlias( BX_reg(context) )))
 479         {
 480             AX_reg(context) = 0x8011;  /* descriptor unavailable */
 481             SET_CFLAG(context);
 482         }
 483         break;
 484
 485     case 0x000b:  /* Get descriptor */
 486         TRACE(int31,"get descriptor (0x%04x)\n",BX_reg(context));
 487         {
 488             ldt_entry entry;
 489             LDT_GetEntry( SELECTOR_TO_ENTRY( BX_reg(context) ), &entry );
 490             /* FIXME: should use ES:EDI for 32-bit clients */
 491             LDT_EntryToBytes( PTR_SEG_OFF_TO_LIN( ES_reg(context),
 492                                                   DI_reg(context) ), &entry );
 493         }
 494         break;
 495
 496     case 0x000c:  /* Set descriptor */
 497         TRACE(int31,"set descriptor (0x%04x)\n",BX_reg(context));
 498         {
 499             ldt_entry entry;
 500             LDT_BytesToEntry( PTR_SEG_OFF_TO_LIN( ES_reg(context),
 501                                                   DI_reg(context) ), &entry );
 502             LDT_SetEntry( SELECTOR_TO_ENTRY( BX_reg(context) ), &entry );
 503         }
 504         break;
 505
 506     case 0x000d:  /* Allocate specific LDT descriptor */
 507         FIXME(int31,"allocate descriptor (0x%04x), stub!\n",BX_reg(context));
 508         AX_reg(context) = 0x8011; /* descriptor unavailable */
 509         SET_CFLAG(context);
 510         break;
 511     case 0x0200: /* get real mode interrupt vector */
 512         FIXME(int31,"get realmode interupt vector(0x%02x) unimplemented.\n",
 513               BL_reg(context));
 514         SET_CFLAG(context);
 515         break;
 516     case 0x0201: /* set real mode interrupt vector */
 517         FIXME(int31, "set realmode interupt vector(0x%02x,0x%04x:0x%04x) unimplemented\n", BL_reg(context),CX_reg(context),DX_reg(context));
 518         SET_CFLAG(context);
 519         break;
 520     case 0x0204:  /* Get protected mode interrupt vector */
 521         TRACE(int31,"get protected mode interrupt handler (0x%02x), stub!\n",BL_reg(context));
 522         dw = (DWORD)INT_GetHandler( BL_reg(context) );
 523         CX_reg(context) = HIWORD(dw);
 524         DX_reg(context) = LOWORD(dw);
 525         break;
 526
 527     case 0x0205:  /* Set protected mode interrupt vector */
 528         TRACE(int31,"set protected mode interrupt handler (0x%02x,0x%08lx), stub!\n",BL_reg(context),PTR_SEG_OFF_TO_LIN(CX_reg(context),DX_reg(context)));
 529         INT_SetHandler( BL_reg(context),
 530                         (FARPROC16)PTR_SEG_OFF_TO_SEGPTR( CX_reg(context),
 531                                                           DX_reg(context) ));
 532         break;
 533
 534     case 0x0300:  /* Simulate real mode interrupt */
 535         INT_DoRealModeInt( context );
 536         break;
 537
 538     case 0x0301:  /* Call real mode procedure with far return */
 539         CallRMProcFar( context );
 540         break;
 541
 542     case 0x0302:  /* Call real mode procedure with interrupt return */
 543         {
 544             REALMODECALL *p = (REALMODECALL *)PTR_SEG_OFF_TO_LIN( ES_reg(context), DI_reg(context) );
 545             FIXME(int31, "RealModeCallIret: EAX=%08lx EBX=%08lx ECX=%08lx EDX=%08lx\n", p->eax, p->ebx, p->ecx, p->edx);
 546             FIXME(int31, "                  ESI=%08lx EDI=%08lx ES=%04x DS=%04x CS:IP=%04x:%04x\n", p->esi, p->edi, p->es, p->ds, p->cs, p->ip );
 547             SET_CFLAG(context);
 548         }
 549         break;
 550
 551     case 0x0303:  /* Allocate Real Mode Callback Address */
 552         AllocRMCB( context );
 553         break;
 554
 555     case 0x0304:  /* Free Real Mode Callback Address */
 556         FreeRMCB( context );
 557         break;
 558
 559     case 0x0400:  /* Get DPMI version */
 560         TRACE(int31,"get DPMI version\n");
 561         {
 562             SYSTEM_INFO si;
 563
 564             GetSystemInfo(&si);
 565             AX_reg(context) = 0x005a;  /* DPMI version 0.90 */
 566             BX_reg(context) = 0x0005;  /* Flags: 32-bit, virtual memory */
 567             CL_reg(context) = si.wProcessorLevel;
 568             DX_reg(context) = 0x0102;  /* Master/slave interrupt controller base*/
 569             break;
 570         }
 571     case 0x0500:  /* Get free memory information */
 572         TRACE(int31,"get free memory information\n");
 573         {
 574             MEMMANINFO mmi;
 575
 576             mmi.dwSize = sizeof(mmi);
 577             MemManInfo(&mmi);
 578             ptr = (BYTE *)PTR_SEG_OFF_TO_LIN(ES_reg(context),DI_reg(context));
 579             /* the layout is just the same as MEMMANINFO, but without
 580              * the dwSize entry.
 581              */
 582             memcpy(ptr,((char*)&mmi)+4,sizeof(mmi)-4);
 583             break;
 584         }
 585     case 0x0501:  /* Allocate memory block */
 586         TRACE(int31,"allocate memory block (%ld)\n",MAKELONG(CX_reg(context),BX_reg(context)));
 587         if (!(ptr = (BYTE *)VirtualAlloc(NULL, MAKELONG(CX_reg(context), BX_reg(context)), MEM_COMMIT, PAGE_EXECUTE_READWRITE)))
 588         {
 589             AX_reg(context) = 0x8012;  /* linear memory not available */
 590             SET_CFLAG(context);
 591         }
 592         else
 593         {
 594             BX_reg(context) = SI_reg(context) = HIWORD(ptr);
 595             CX_reg(context) = DI_reg(context) = LOWORD(ptr);
 596         }
 597         break;
 598
 599     case 0x0502:  /* Free memory block */
 600         TRACE(int31,"free memory block (0x%08lx)\n",MAKELONG(DI_reg(context),SI_reg(context)));
 601         VirtualFree((void *)MAKELONG(DI_reg(context), SI_reg(context)), 0, MEM_RELEASE);
 602         break;
 603
 604     case 0x0503:  /* Resize memory block */
 605         TRACE(int31,"resize memory block (0x%08lx,%ld)\n",MAKELONG(DI_reg(context),SI_reg(context)),MAKELONG(CX_reg(context),BX_reg(context)));
 606         if (!(ptr = (BYTE *)HeapReAlloc( GetProcessHeap(), 0,
 607                            (void *)MAKELONG(DI_reg(context),SI_reg(context)),
 608                                    MAKELONG(CX_reg(context),BX_reg(context)))))
 609         {
 610             AX_reg(context) = 0x8012;  /* linear memory not available */
 611             SET_CFLAG(context);
 612         }
 613         else
 614         {
 615             BX_reg(context) = SI_reg(context) = HIWORD(ptr);
 616             CX_reg(context) = DI_reg(context) = LOWORD(ptr);
 617         }
 618         break;
 619
 620     case 0x0600:  /* Lock linear region */
 621         FIXME(int31,"lock linear region unimplemented\n");
 622         break;  /* Just ignore it */
 623
 624     case 0x0601:  /* Unlock linear region */
 625         FIXME(int31,"unlock linear region unimplemented\n");
 626         break;  /* Just ignore it */
 627
 628     case 0x0602:  /* Unlock real-mode region */
 629         FIXME(int31,"unlock realmode region unimplemented\n");
 630         break;  /* Just ignore it */
 631
 632     case 0x0603:  /* Lock real-mode region */
 633         FIXME(int31,"lock realmode region unimplemented\n");
 634         break;  /* Just ignore it */
 635
 636     case 0x0604:  /* Get page size */
 637         TRACE(int31,"get pagesize\n");
 638         BX_reg(context) = 0;
 639         CX_reg(context) = VIRTUAL_GetPageSize();
 640         break;
 641
 642     case 0x0702:  /* Mark page as demand-paging candidate */
 643         FIXME(int31,"mark page as demand-paging candidate\n");
 644         break;  /* Just ignore it */
 645
 646     case 0x0703:  /* Discard page contents */
 647         FIXME(int31,"discard page contents\n");
 648         break;  /* Just ignore it */
 649
 650      case 0x0800:  /* Physical address mapping */
 651         FIXME(int31,"map real to linear (0x%08lx)\n",MAKELONG(CX_reg(context),BX_reg(context)));
 652          if(!(ptr=DOSMEM_MapRealToLinear(MAKELONG(CX_reg(context),BX_reg(context)))))
 653          {
 654              AX_reg(context) = 0x8021;
 655              SET_CFLAG(context);
 656          }
 657          else
 658          {
 659              BX_reg(context) = HIWORD(ptr);
 660              CX_reg(context) = LOWORD(ptr);
 661              RESET_CFLAG(context);
 662          }
 663          break;
 664
 665     default:
 666         INT_BARF( context, 0x31 );
 667         AX_reg(context) = 0x8001;  /* unsupported function */
 668         SET_CFLAG(context);
 669         break;
 670     }
 671 }