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 "windef.h"
  10 #include "wine/winbase16.h"
  11 #include "ldt.h"
  12 #include "builtin16.h"
  13 #include "global.h"
  14 #include "miscemu.h"
  15 #include "msdos.h"
  16 #include "dosexe.h"
  17 #include "task.h"
  18 #include "toolhelp.h"
  19 #include "selectors.h"
  20 #include "process.h"
  21 #include "callback.h"
  22 #include "debugtools.h"
  23
  24 DEFAULT_DEBUG_CHANNEL(int31);
  25
  26 #define DOS_GET_DRIVE(reg) ((reg) ? (reg) - 1 : DRIVE_GetCurrentDrive())
  27
  28 void CreateBPB(int drive, BYTE *data, BOOL16 limited);  /* defined in int21.c */
  29
  30 static void* lastvalloced = NULL;
  31
  32 /* Structure for real-mode callbacks */
  33 typedef struct
  34 {
  35     DWORD edi;
  36     DWORD esi;
  37     DWORD ebp;
  38     DWORD reserved;
  39     DWORD ebx;
  40     DWORD edx;
  41     DWORD ecx;
  42     DWORD eax;
  43     WORD  fl;
  44     WORD  es;
  45     WORD  ds;
  46     WORD  fs;
  47     WORD  gs;
  48     WORD  ip;
  49     WORD  cs;
  50     WORD  sp;
  51     WORD  ss;
  52 } REALMODECALL;
  53
  54
  55
  56 typedef struct tagRMCB {
  57     DWORD address;
  58     DWORD proc_ofs,proc_sel;
  59     DWORD regs_ofs,regs_sel;
  60     struct tagRMCB *next;
  61 } RMCB;
  62
  63 static RMCB *FirstRMCB = NULL;
  64
  65
  66 /**********************************************************************
  67  *          DPMI_xalloc
  68  * special virtualalloc, allocates lineary monoton growing memory.
  69  * (the usual VirtualAlloc does not satisfy that restriction)
  70  */
  71 static LPVOID
  72 DPMI_xalloc(int len) {
  73         LPVOID  ret;
  74         LPVOID  oldlastv = lastvalloced;
  75
  76         if (lastvalloced) {
  77                 int     xflag = 0;
  78                 ret = NULL;
  79                 while (!ret) {
  80                         ret=VirtualAlloc(lastvalloced,len,MEM_COMMIT|MEM_RESERVE,PAGE_EXECUTE_READWRITE);
  81                         if (!ret)
  82                                 lastvalloced = (char *) lastvalloced + 0x10000;
  83                         /* we failed to allocate one in the first round.
  84                          * try non-linear
  85                          */
  86                         if (!xflag && (lastvalloced<oldlastv)) { /* wrapped */
  87                                 FIXME("failed to allocate lineary growing memory (%d bytes), using non-linear growing...\n",len);
  88                                 xflag++;
  89                         }
  90                         /* if we even fail to allocate something in the next
  91                          * round, return NULL
  92                          */
  93                         if ((xflag==1) && (lastvalloced >= oldlastv))
  94                                 xflag++;
  95                         if ((xflag==2) && (lastvalloced < oldlastv)) {
  96                                 FIXME("failed to allocate any memory of %d bytes!\n",len);
  97                                 return NULL;
  98                         }
  99                 }
 100         } else
 101                  ret=VirtualAlloc(NULL,len,MEM_COMMIT|MEM_RESERVE,PAGE_EXECUTE_READWRITE);
 102         lastvalloced = (LPVOID)(((DWORD)ret+len+0xffff)&~0xffff);
 103         return ret;
 104 }
 105
 106 static void
 107 DPMI_xfree(LPVOID ptr) {
 108         VirtualFree(ptr,0,MEM_RELEASE);
 109 }
 110
 111 /* FIXME: perhaps we could grow this mapped area... */
 112 static LPVOID
 113 DPMI_xrealloc(LPVOID ptr,int newsize) {
 114         MEMORY_BASIC_INFORMATION        mbi;
 115         LPVOID                          newptr;
 116
 117         newptr = DPMI_xalloc(newsize);
 118         if (ptr) {
 119                 if (!VirtualQuery(ptr,&mbi,sizeof(mbi))) {
 120                         FIXME("realloc of DPMI_xallocd region %p?\n",ptr);
 121                         return NULL;
 122                 }
 123                 if (mbi.State == MEM_FREE) {
 124                         FIXME("realloc of DPMI_xallocd region %p?\n",ptr);
 125                         return NULL;
 126                 }
 127                 /* We do not shrink allocated memory. most reallocs
 128                  * only do grows anyway
 129                  */
 130                 if (newsize<=mbi.RegionSize)
 131                         return ptr;
 132                 memcpy(newptr,ptr,mbi.RegionSize);
 133                 DPMI_xfree(ptr);
 134         }
 135         return newptr;
 136 }
 137 /**********************************************************************
 138  *          INT_GetRealModeContext
 139  */
 140 static void INT_GetRealModeContext( REALMODECALL *call, CONTEXT86 *context )
 141 {
 142     context->Eax    = call->eax;
 143     context->Ebx    = call->ebx;
 144     context->Ecx    = call->ecx;
 145     context->Edx    = call->edx;
 146     context->Esi    = call->esi;
 147     context->Edi    = call->edi;
 148     context->Ebp    = call->ebp;
 149     context->EFlags = call->fl | V86_FLAG;
 150     context->Eip    = call->ip;
 151     context->Esp    = call->sp;
 152     context->SegCs  = call->cs;
 153     context->SegDs  = call->ds;
 154     context->SegEs  = call->es;
 155     context->SegFs  = call->fs;
 156     context->SegGs  = call->gs;
 157     context->SegSs  = call->ss;
 158 }
 159
 160
 161 /**********************************************************************
 162  *          INT_SetRealModeContext
 163  */
 164 static void INT_SetRealModeContext( REALMODECALL *call, CONTEXT86 *context )
 165 {
 166     call->eax = context->Eax;
 167     call->ebx = context->Ebx;
 168     call->ecx = context->Ecx;
 169     call->edx = context->Edx;
 170     call->esi = context->Esi;
 171     call->edi = context->Edi;
 172     call->ebp = context->Ebp;
 173     call->fl  = LOWORD(context->EFlags);
 174     call->ip  = LOWORD(context->Eip);
 175     call->sp  = LOWORD(context->Esp);
 176     call->cs  = context->SegCs;
 177     call->ds  = context->SegDs;
 178     call->es  = context->SegEs;
 179     call->fs  = context->SegFs;
 180     call->gs  = context->SegGs;
 181     call->ss  = context->SegSs;
 182 }
 183
 184 #ifdef __i386__
 185
 186 void DPMI_CallRMCB32(RMCB *rmcb, UINT16 ss, DWORD esp, UINT16*es, DWORD*edi)
 187 #if 0 /* original code, which early gccs puke on */
 188 {
 189     int _clobber;
 190     __asm__ __volatile__(
 191         "pushl %%ebp\n"
 192         "pushl %%ebx\n"
 193         "pushl %%es\n"
 194         "pushl %%ds\n"
 195         "pushfl\n"
 196         "mov %7,%%es\n"
 197         "mov %5,%%ds\n"
 198         ".byte 0x36, 0xff, 0x18\n" /* lcall *%ss:(%eax) */
 199         "popl %%ds\n"
 200         "mov %%es,%0\n"
 201         "popl %%es\n"
 202         "popl %%ebx\n"
 203         "popl %%ebp\n"
 204     : "=d" (*es), "=D" (*edi), "=S" (_clobber), "=a" (_clobber), "=c" (_clobber)
 205     : "0" (ss), "2" (esp),
 206       "4" (rmcb->regs_sel), "1" (rmcb->regs_ofs),
 207       "3" (&rmcb->proc_ofs) );
 208 }
 209 #else /* code generated by a gcc new enough */
 210 ;
 211 __ASM_GLOBAL_FUNC(DPMI_CallRMCB32,
 212     "pushl %ebp\n\t"
 213     "movl %esp,%ebp\n\t"
 214     "pushl %edi\n\t"
 215     "pushl %esi\n\t"
 216     "movl 0x8(%ebp),%eax\n\t"
 217     "movl 0x10(%ebp),%esi\n\t"
 218     "movl 0xc(%ebp),%edx\n\t"
 219     "movl 0x10(%eax),%ecx\n\t"
 220     "movl 0xc(%eax),%edi\n\t"
 221     "addl $0x4,%eax\n\t"
 222     "pushl %ebp\n\t"
 223     "pushl %ebx\n\t"
 224     "pushl %es\n\t"
 225     "pushl %ds\n\t"
 226     "pushfl\n\t"
 227     "mov %cx,%es\n\t"
 228     "mov %dx,%ds\n\t"
 229     ".byte 0x36, 0xff, 0x18\n\t" /* lcall *%ss:(%eax) */
 230     "popl %ds\n\t"
 231     "mov %es,%dx\n\t"
 232     "popl %es\n\t"
 233     "popl %ebx\n\t"
 234     "popl %ebp\n\t"
 235     "movl 0x14(%ebp),%eax\n\t"
 236     "movw %dx,(%eax)\n\t"
 237     "movl 0x18(%ebp),%edx\n\t"
 238     "movl %edi,(%edx)\n\t"
 239     "popl %esi\n\t"
 240     "popl %edi\n\t"
 241     "leave\n\t"
 242     "ret")
 243 #endif
 244
 245 #endif /* __i386__ */
 246
 247 /**********************************************************************
 248  *          DPMI_CallRMCBProc
 249  *
 250  * This routine does the hard work of calling a callback procedure.
 251  */
 252 static void DPMI_CallRMCBProc( CONTEXT86 *context, RMCB *rmcb, WORD flag )
 253 {
 254     if (IS_SELECTOR_SYSTEM( rmcb->proc_sel )) {
 255         /* Wine-internal RMCB, call directly */
 256         ((RMCBPROC)rmcb->proc_ofs)(context);
 257     } else {
 258 #ifdef __i386__
 259         UINT16 ss,es;
 260         DWORD esp,edi;
 261
 262         INT_SetRealModeContext((REALMODECALL *)PTR_SEG_OFF_TO_LIN( rmcb->regs_sel, rmcb->regs_ofs ), context);
 263         ss = SELECTOR_AllocBlock( (void *)(context->SegSs<<4), 0x10000, SEGMENT_DATA, FALSE, FALSE );
 264         esp = context->Esp;
 265
 266         FIXME("untested!\n");
 267
 268         /* The called proc ends with an IRET, and takes these parameters:
 269          * DS:ESI = pointer to real-mode SS:SP
 270          * ES:EDI = pointer to real-mode call structure
 271          * It returns:
 272          * ES:EDI = pointer to real-mode call structure (may be a copy)
 273          * It is the proc's responsibility to change the return CS:IP in the
 274          * real-mode call structure. */
 275         if (flag & 1) {
 276             /* 32-bit DPMI client */
 277             DPMI_CallRMCB32(rmcb, ss, esp, &es, &edi);
 278         } else {
 279             /* 16-bit DPMI client */
 280             CONTEXT86 ctx = *context;
 281             ctx.SegCs = rmcb->proc_sel;
 282             ctx.Eip   = rmcb->proc_ofs;
 283             ctx.SegDs = ss;
 284             ctx.Esi   = esp;
 285             ctx.SegEs = rmcb->regs_sel;
 286             ctx.Edi   = rmcb->regs_ofs;
 287             /* FIXME: I'm pretty sure this isn't right - should push flags first */
 288             CallTo16RegisterShort(&ctx, 0);
 289             es = ctx.SegEs;
 290             edi = ctx.Edi;
 291         }
 292         FreeSelector16(ss);
 293         INT_GetRealModeContext((REALMODECALL*)PTR_SEG_OFF_TO_LIN( es, edi ), context);
 294 #else
 295         ERR("RMCBs only implemented for i386\n");
 296 #endif
 297     }
 298 }
 299
 300
 301 /**********************************************************************
 302  *          DPMI_CallRMProc
 303  *
 304  * This routine does the hard work of calling a real mode procedure.
 305  */
 306 int DPMI_CallRMProc( CONTEXT86 *context, LPWORD stack, int args, int iret )
 307 {
 308     LPWORD stack16;
 309     LPVOID addr = NULL; /* avoid gcc warning */
 310     LPDOSTASK lpDosTask = MZ_Current();
 311     RMCB *CurrRMCB;
 312     int alloc = 0, already = 0;
 313     BYTE *code;
 314
 315     GlobalUnlock16( GetCurrentTask() );
 316
 317     TRACE("EAX=%08lx EBX=%08lx ECX=%08lx EDX=%08lx\n",
 318                  context->Eax, context->Ebx, context->Ecx, context->Edx );
 319     TRACE("ESI=%08lx EDI=%08lx ES=%04lx DS=%04lx CS:IP=%04lx:%04x, %d WORD arguments, %s\n",
 320                  context->Esi, context->Edi, context->SegEs, context->SegDs,
 321                  context->SegCs, LOWORD(context->Eip), args, iret?"IRET":"FAR" );
 322
 323 callrmproc_again:
 324
 325 /* there might be some code that just jumps to RMCBs or the like,
 326    in which case following the jumps here might get us to a shortcut */
 327     code = CTX_SEG_OFF_TO_LIN(context, context->SegCs, context->Eip);
 328     switch (*code) {
 329     case 0xe9: /* JMP NEAR */
 330       context->Eip += 3 + *(WORD *)(code+1);
 331       /* yeah, I know these gotos don't look good... */
 332       goto callrmproc_again;
 333     case 0xea: /* JMP FAR */
 334       context->Eip = *(WORD *)(code+1);
 335       context->SegCs = *(WORD *)(code+3);
 336       /* ...but since the label is there anyway... */
 337       goto callrmproc_again;
 338     case 0xeb: /* JMP SHORT */
 339       context->Eip += 2 + *(signed char *)(code+1);
 340       /* ...because of other gotos below, so... */
 341       goto callrmproc_again;
 342     }
 343
 344 /* shortcut for chaining to internal interrupt handlers */
 345     if ((context->SegCs == 0xF000) && iret) {
 346         return INT_RealModeInterrupt( LOWORD(context->Eip)/4, context);
 347     }
 348
 349 /* shortcut for RMCBs */
 350     CurrRMCB = FirstRMCB;
 351
 352     while (CurrRMCB && (HIWORD(CurrRMCB->address) != context->SegCs))
 353         CurrRMCB = CurrRMCB->next;
 354
 355     if (!(CurrRMCB || lpDosTask)) {
 356         FIXME("DPMI real-mode call using DOS VM task system, not fully tested!\n");
 357         TRACE("creating VM86 task\n");
 358         if (!(lpDosTask = MZ_AllocDPMITask() )) {
 359             ERR("could not setup VM86 task\n");
 360             return 1;
 361         }
 362     }
 363     if (!already) {
 364         if (!context->SegSs) {
 365             alloc = 1; /* allocate default stack */
 366             stack16 = addr = DOSMEM_GetBlock( 64, (UINT16 *)&(context->SegSs) );
 367             context->Esp = 64-2;
 368             stack16 += 32-1;
 369             if (!addr) {
 370                 ERR("could not allocate default stack\n");
 371                 return 1;
 372             }
 373         } else {
 374             stack16 = CTX_SEG_OFF_TO_LIN(context, context->SegSs, context->Esp);
 375         }
 376         context->Esp -= (args + (iret?1:0)) * sizeof(WORD);
 377         stack16 -= args;
 378         if (args) memcpy(stack16, stack, args*sizeof(WORD) );
 379         /* push flags if iret */
 380         if (iret) {
 381             stack16--; args++;
 382             *stack16 = LOWORD(context->EFlags);
 383         }
 384         /* push return address (return to interrupt wrapper) */
 385         *(--stack16) = DOSMEM_wrap_seg;
 386         *(--stack16) = 0;
 387         /* adjust stack */
 388         context->Esp -= 2*sizeof(WORD);
 389         already = 1;
 390     }
 391
 392     if (CurrRMCB) {
 393         /* RMCB call, invoke protected-mode handler directly */
 394         DPMI_CallRMCBProc(context, CurrRMCB, lpDosTask ? lpDosTask->dpmi_flag : 0);
 395         /* check if we returned to where we thought we would */
 396         if ((context->SegCs != DOSMEM_wrap_seg) ||
 397             (LOWORD(context->Eip) != 0)) {
 398             /* we need to continue at different address in real-mode space,
 399                so we need to set it all up for real mode again */
 400             goto callrmproc_again;
 401         }
 402     } else {
 403         TRACE("entering real mode...\n");
 404         DOSVM_Enter( context );
 405         TRACE("returned from real-mode call\n");
 406     }
 407     if (alloc) DOSMEM_FreeBlock( addr );
 408     return 0;
 409 }
 410
 411
 412 /**********************************************************************
 413  *          CallRMInt
 414  */
 415 static void CallRMInt( CONTEXT86 *context )
 416 {
 417     CONTEXT86 realmode_ctx;
 418     FARPROC16 rm_int = INT_GetRMHandler( BL_reg(context) );
 419     REALMODECALL *call = (REALMODECALL *)PTR_SEG_OFF_TO_LIN( context->SegEs,
 420                                                           DI_reg(context) );
 421     INT_GetRealModeContext( call, &realmode_ctx );
 422
 423     /* we need to check if a real-mode program has hooked the interrupt */
 424     if (HIWORD(rm_int)!=0xF000) {
 425         /* yup, which means we need to switch to real mode... */
 426         realmode_ctx.SegCs = HIWORD(rm_int);
 427         realmode_ctx.Eip   = LOWORD(rm_int);
 428         if (DPMI_CallRMProc( &realmode_ctx, NULL, 0, TRUE))
 429           SET_CFLAG(context);
 430     } else {
 431         RESET_CFLAG(context);
 432         /* use the IP we have instead of BL_reg, in case some apps
 433            decide to move interrupts around for whatever reason... */
 434         if (INT_RealModeInterrupt( LOWORD(rm_int)/4, &realmode_ctx ))
 435           SET_CFLAG(context);
 436         if (context->EFlags & 1) {
 437           FIXME("%02x: EAX=%08lx EBX=%08lx ECX=%08lx EDX=%08lx\n",
 438                 BL_reg(context), realmode_ctx.Eax, realmode_ctx.Ebx,
 439                 realmode_ctx.Ecx, realmode_ctx.Edx);
 440           FIXME("      ESI=%08lx EDI=%08lx DS=%04lx ES=%04lx\n",
 441                 realmode_ctx.Esi, realmode_ctx.Edi,
 442                 realmode_ctx.SegDs, realmode_ctx.SegEs );
 443         }
 444     }
 445     INT_SetRealModeContext( call, &realmode_ctx );
 446 }
 447
 448
 449 static void CallRMProc( CONTEXT86 *context, int iret )
 450 {
 451     REALMODECALL *p = (REALMODECALL *)PTR_SEG_OFF_TO_LIN( context->SegEs, DI_reg(context) );
 452     CONTEXT86 context16;
 453
 454     TRACE("RealModeCall: EAX=%08lx EBX=%08lx ECX=%08lx EDX=%08lx\n",
 455         p->eax, p->ebx, p->ecx, p->edx);
 456     TRACE("              ESI=%08lx EDI=%08lx ES=%04x DS=%04x CS:IP=%04x:%04x, %d WORD arguments, %s\n",
 457         p->esi, p->edi, p->es, p->ds, p->cs, p->ip, CX_reg(context), iret?"IRET":"FAR" );
 458
 459     if (!(p->cs) && !(p->ip)) { /* remove this check
 460                                    if Int21/6501 case map function
 461                                    has been implemented */
 462         SET_CFLAG(context);
 463         return;
 464     }
 465     INT_GetRealModeContext(p, &context16);
 466     DPMI_CallRMProc( &context16, ((LPWORD)PTR_SEG_OFF_TO_LIN(context->SegSs, LOWORD(context->Esp)))+3,
 467                      CX_reg(context), iret );
 468     INT_SetRealModeContext(p, &context16);
 469 }
 470
 471
 472 static RMCB *DPMI_AllocRMCB( void )
 473 {
 474     RMCB *NewRMCB = HeapAlloc(GetProcessHeap(), 0, sizeof(RMCB));
 475     UINT16 uParagraph;
 476
 477     if (NewRMCB)
 478     {
 479         LPVOID RMCBmem = DOSMEM_GetBlock(4, &uParagraph);
 480         LPBYTE p = RMCBmem;
 481
 482         *p++ = 0xcd; /* RMCB: */
 483         *p++ = 0x31; /* int $0x31 */
 484 /* it is the called procedure's task to change the return CS:EIP
 485    the DPMI 0.9 spec states that if it doesn't, it will be called again */
 486         *p++ = 0xeb;
 487         *p++ = 0xfc; /* jmp RMCB */
 488         NewRMCB->address = MAKELONG(0, uParagraph);
 489         NewRMCB->next = FirstRMCB;
 490         FirstRMCB = NewRMCB;
 491     }
 492     return NewRMCB;
 493 }
 494
 495
 496 static void AllocRMCB( CONTEXT86 *context )
 497 {
 498     RMCB *NewRMCB = DPMI_AllocRMCB();
 499
 500     TRACE("Function to call: %04x:%04x\n", (WORD)context->SegDs, SI_reg(context) );
 501
 502     if (NewRMCB)
 503     {
 504         /* FIXME: if 32-bit DPMI client, use ESI and EDI */
 505         NewRMCB->proc_ofs = LOWORD(context->Esi);
 506         NewRMCB->proc_sel = context->SegDs;
 507         NewRMCB->regs_ofs = LOWORD(context->Edi);
 508         NewRMCB->regs_sel = context->SegEs;
 509         SET_LOWORD( context->Ecx, HIWORD(NewRMCB->address) );
 510         SET_LOWORD( context->Edx, LOWORD(NewRMCB->address) );
 511     }
 512     else
 513     {
 514         SET_LOWORD( context->Eax, 0x8015 ); /* callback unavailable */
 515         SET_CFLAG(context);
 516     }
 517 }
 518
 519
 520 FARPROC16 WINAPI DPMI_AllocInternalRMCB( RMCBPROC proc )
 521 {
 522     RMCB *NewRMCB = DPMI_AllocRMCB();
 523
 524     if (NewRMCB) {
 525         NewRMCB->proc_ofs = (DWORD)proc;
 526         NewRMCB->proc_sel = 0;
 527         NewRMCB->regs_ofs = 0;
 528         NewRMCB->regs_sel = 0;
 529         return (FARPROC16)(NewRMCB->address);
 530     }
 531     return NULL;
 532 }
 533
 534
 535 static int DPMI_FreeRMCB( DWORD address )
 536 {
 537     RMCB *CurrRMCB = FirstRMCB;
 538     RMCB *PrevRMCB = NULL;
 539
 540     while (CurrRMCB && (CurrRMCB->address != address))
 541     {
 542         PrevRMCB = CurrRMCB;
 543         CurrRMCB = CurrRMCB->next;
 544     }
 545     if (CurrRMCB)
 546     {
 547         if (PrevRMCB)
 548         PrevRMCB->next = CurrRMCB->next;
 549             else
 550         FirstRMCB = CurrRMCB->next;
 551         DOSMEM_FreeBlock(DOSMEM_MapRealToLinear(CurrRMCB->address));
 552         HeapFree(GetProcessHeap(), 0, CurrRMCB);
 553         return 0;
 554     }
 555     return 1;
 556 }
 557
 558
 559 static void FreeRMCB( CONTEXT86 *context )
 560 {
 561     FIXME("callback address: %04x:%04x\n",
 562           CX_reg(context), DX_reg(context));
 563
 564     if (DPMI_FreeRMCB(MAKELONG(DX_reg(context), CX_reg(context)))) {
 565         SET_LOWORD( context->Eax, 0x8024 ); /* invalid callback address */
 566         SET_CFLAG(context);
 567     }
 568 }
 569
 570
 571 void WINAPI DPMI_FreeInternalRMCB( FARPROC16 proc )
 572 {
 573     DPMI_FreeRMCB( (DWORD)proc );
 574 }
 575
 576
 577 /* (see dosmem.c, function DOSMEM_InitDPMI) */
 578
 579 static void StartPM( CONTEXT86 *context, LPDOSTASK lpDosTask )
 580 {
 581     UINT16 cs, ss, ds, es;
 582     CONTEXT86 pm_ctx;
 583     DWORD psp_ofs = (DWORD)(lpDosTask->psp_seg<<4);
 584     PDB16 *psp = (PDB16 *)psp_ofs;
 585     HANDLE16 env_seg = psp->environment;
 586     int is32;
 587
 588     RESET_CFLAG(context);
 589     lpDosTask->dpmi_flag = AX_reg(context);
 590     is32 = lpDosTask->dpmi_flag & 1;
 591 /* our mode switch wrapper have placed the desired CS into DX */
 592     cs = SELECTOR_AllocBlock( (void *)(DX_reg(context)<<4), 0x10000, SEGMENT_CODE, FALSE, FALSE );
 593 /* due to a flaw in some CPUs (at least mine), it is best to mark stack segments as 32-bit if they
 594    can be used in 32-bit code. Otherwise, these CPUs may not set the high word of esp during a
 595    ring transition (from kernel code) to the 16-bit stack, and this causes trouble if executing
 596    32-bit code using this stack. */
 597     ss = SELECTOR_AllocBlock( (void *)(context->SegSs<<4), 0x10000, SEGMENT_DATA, is32, FALSE );
 598 /* do the same for the data segments, just in case */
 599     if (context->SegDs == context->SegSs) ds = ss;
 600     else ds = SELECTOR_AllocBlock( (void *)(context->SegDs<<4), 0x10000, SEGMENT_DATA, is32, FALSE );
 601     es = SELECTOR_AllocBlock( psp, 0x100, SEGMENT_DATA, is32, FALSE );
 602 /* convert environment pointer, as the spec says, but we're a bit lazy about the size here... */
 603     psp->environment = SELECTOR_AllocBlock( (void *)(env_seg<<4),
 604                                             0x10000, SEGMENT_DATA, FALSE, FALSE );
 605
 606     pm_ctx = *context;
 607     pm_ctx.SegCs = DOSMEM_dpmi_sel;
 608 /* our mode switch wrapper expects the new CS in DX, and the new SS in AX */
 609     pm_ctx.Eax   = ss;
 610     pm_ctx.Edx   = cs;
 611     pm_ctx.SegDs = ds;
 612     pm_ctx.SegEs = es;
 613     pm_ctx.SegFs = 0;
 614     pm_ctx.SegGs = 0;
 615
 616     TRACE("DOS program is now entering protected mode\n");
 617     CallTo16RegisterShort(&pm_ctx, 0);
 618
 619     /* in the current state of affairs, we won't ever actually return here... */
 620     /* we should have int21/ah=4c do it someday, though... */
 621
 622     FreeSelector16(psp->environment);
 623     psp->environment = env_seg;
 624     FreeSelector16(es);
 625     if (ds != ss) FreeSelector16(ds);
 626     FreeSelector16(ss);
 627     FreeSelector16(cs);
 628 }
 629
 630 /* DPMI Raw Mode Switch handler */
 631
 632 #if 0
 633 void WINAPI DPMI_RawModeSwitch( SIGCONTEXT *context )
 634 {
 635   LPDOSTASK lpDosTask = MZ_Current();
 636   CONTEXT86 rm_ctx;
 637   int ret;
 638
 639   if (!lpDosTask) {
 640     /* we could probably start a DPMI-only dosmod task here, but I doubt
 641        anything other than real DOS apps want to call raw mode switch */
 642     ERR("attempting raw mode switch without DOS task!\n");
 643     ExitProcess(1);
 644   }
 645   /* initialize real-mode context as per spec */
 646   memset(&rm_ctx, 0, sizeof(rm_ctx));
 647   rm_ctx.SegDs  = AX_sig(context);
 648   rm_ctx.SegEs  = CX_sig(context);
 649   rm_ctx.SegSs  = DX_sig(context);
 650   rm_ctx.Esp    = EBX_sig(context);
 651   rm_ctx.SegCs  = SI_sig(context);
 652   rm_ctx.Eip    = EDI_sig(context);
 653   rm_ctx.Ebp    = EBP_sig(context);
 654   rm_ctx.SegFs  = 0;
 655   rm_ctx.SegGs  = 0;
 656   rm_ctx.EFlags = EFL_sig(context); /* at least we need the IF flag */
 657
 658   /* enter real mode again */
 659   TRACE("re-entering real mode at %04lx:%04lx\n",rm_ctx.SegCs,rm_ctx.Eip);
 660   ret = DOSVM_Enter( &rm_ctx );
 661   /* when the real-mode stuff call its mode switch address,
 662      DOSVM_Enter will return and we will continue here */
 663
 664   if (ret<0) {
 665     /* if the sync was lost, there's no way to recover */
 666     ExitProcess(1);
 667   }
 668
 669   /* alter protected-mode context as per spec */
 670   DS_sig(context)  = LOWORD(rm_ctx.Eax);
 671   ES_sig(context)  = LOWORD(rm_ctx.Ecx);
 672   SS_sig(context)  = LOWORD(rm_ctx.Edx);
 673   ESP_sig(context) = rm_ctx.Ebx;
 674   CS_sig(context)  = LOWORD(rm_ctx.Esi);
 675   EIP_sig(context) = rm_ctx.Edi;
 676   EBP_sig(context) = rm_ctx.Ebp;
 677   FS_sig(context) = 0;
 678   GS_sig(context) = 0;
 679
 680   /* Return to new address and hope that we didn't mess up */
 681   TRACE("re-entering protected mode at %04x:%08lx\n",
 682         CS_sig(context), EIP_sig(context));
 683 }
 684 #endif
 685
 686
 687 /**********************************************************************
 688  *          INT_Int31Handler
 689  *
 690  * Handler for int 31h (DPMI).
 691  */
 692
 693 void WINAPI INT_Int31Handler( CONTEXT86 *context )
 694 {
 695     /*
 696      * Note: For Win32s processes, the whole linear address space is
 697      *       shifted by 0x10000 relative to the OS linear address space.
 698      *       See the comment in msdos/vxd.c.
 699      */
 700     DWORD offset = W32S_APPLICATION() ? W32S_OFFSET : 0;
 701
 702     DWORD dw;
 703     BYTE *ptr;
 704
 705     LPDOSTASK lpDosTask = MZ_Current();
 706
 707     if (ISV86(context) && lpDosTask) {
 708         /* Called from real mode, check if it's our wrapper */
 709         TRACE("called from real mode\n");
 710         if (context->SegCs==DOSMEM_dpmi_seg) {
 711             /* This is the protected mode switch */
 712             StartPM(context,lpDosTask);
 713             return;
 714         } else
 715         if (context->SegCs==DOSMEM_xms_seg) {
 716             /* This is the XMS driver entry point */
 717             XMS_Handler(context);
 718             return;
 719         } else
 720         {
 721             /* Check for RMCB */
 722             RMCB *CurrRMCB = FirstRMCB;
 723
 724             while (CurrRMCB && (HIWORD(CurrRMCB->address) != context->SegCs))
 725                 CurrRMCB = CurrRMCB->next;
 726
 727             if (CurrRMCB) {
 728                 /* RMCB call, propagate to protected-mode handler */
 729                 DPMI_CallRMCBProc(context, CurrRMCB, lpDosTask->dpmi_flag);
 730                 return;
 731             }
 732         }
 733     }
 734
 735     RESET_CFLAG(context);
 736     switch(AX_reg(context))
 737     {
 738     case 0x0000:  /* Allocate LDT descriptors */
 739         TRACE("allocate LDT descriptors (%d)\n",CX_reg(context));
 740         if (!(context->Eax = AllocSelectorArray16( CX_reg(context) )))
 741         {
 742             TRACE("failed\n");
 743             context->Eax = 0x8011;  /* descriptor unavailable */
 744             SET_CFLAG(context);
 745         }
 746         TRACE("success, array starts at 0x%04x\n",AX_reg(context));
 747         break;
 748
 749     case 0x0001:  /* Free LDT descriptor */
 750         TRACE("free LDT descriptor (0x%04x)\n",BX_reg(context));
 751         if (FreeSelector16( BX_reg(context) ))
 752         {
 753             context->Eax = 0x8022;  /* invalid selector */
 754             SET_CFLAG(context);
 755         }
 756         else
 757         {
 758             /* If a segment register contains the selector being freed, */
 759             /* set it to zero. */
 760             if (!((context->SegDs^BX_reg(context)) & ~3)) context->SegDs = 0;
 761             if (!((context->SegEs^BX_reg(context)) & ~3)) context->SegEs = 0;
 762             if (!((context->SegFs^BX_reg(context)) & ~3)) context->SegFs = 0;
 763             if (!((context->SegGs^BX_reg(context)) & ~3)) context->SegGs = 0;
 764         }
 765         break;
 766
 767     case 0x0002:  /* Real mode segment to descriptor */
 768         TRACE("real mode segment to descriptor (0x%04x)\n",BX_reg(context));
 769         {
 770             WORD entryPoint = 0;  /* KERNEL entry point for descriptor */
 771             switch(BX_reg(context))
 772             {
 773             case 0x0000: entryPoint = 183; break;  /* __0000H */
 774             case 0x0040: entryPoint = 193; break;  /* __0040H */
 775             case 0xa000: entryPoint = 174; break;  /* __A000H */
 776             case 0xb000: entryPoint = 181; break;  /* __B000H */
 777             case 0xb800: entryPoint = 182; break;  /* __B800H */
 778             case 0xc000: entryPoint = 195; break;  /* __C000H */
 779             case 0xd000: entryPoint = 179; break;  /* __D000H */
 780             case 0xe000: entryPoint = 190; break;  /* __E000H */
 781             case 0xf000: entryPoint = 194; break;  /* __F000H */
 782             default:
 783                 context->Eax = DOSMEM_AllocSelector(BX_reg(context));
 784                 break;
 785             }
 786             if (entryPoint)
 787                 context->Eax = LOWORD(NE_GetEntryPoint( GetModuleHandle16( "KERNEL" ),
 788                                                             entryPoint ));
 789         }
 790         break;
 791
 792     case 0x0003:  /* Get next selector increment */
 793         TRACE("get selector increment (__AHINCR)\n");
 794         context->Eax = __AHINCR;
 795         break;
 796
 797     case 0x0004:  /* Lock selector (not supported) */
 798         FIXME("lock selector not supported\n");
 799         context->Eax = 0;  /* FIXME: is this a correct return value? */
 800         break;
 801
 802     case 0x0005:  /* Unlock selector (not supported) */
 803         FIXME("unlock selector not supported\n");
 804         context->Eax = 0;  /* FIXME: is this a correct return value? */
 805         break;
 806
 807     case 0x0006:  /* Get selector base address */
 808         TRACE("get selector base address (0x%04x)\n",BX_reg(context));
 809         if (!(dw = GetSelectorBase( BX_reg(context) )))
 810         {
 811             context->Eax = 0x8022;  /* invalid selector */
 812             SET_CFLAG(context);
 813         }
 814         else
 815         {
 816             CX_reg(context) = HIWORD(W32S_WINE2APP(dw, offset));
 817             DX_reg(context) = LOWORD(W32S_WINE2APP(dw, offset));
 818         }
 819         break;
 820
 821     case 0x0007:  /* Set selector base address */
 822         TRACE("set selector base address (0x%04x,0x%08lx)\n",
 823                      BX_reg(context),
 824                      W32S_APP2WINE(MAKELONG(DX_reg(context),CX_reg(context)), offset));
 825         dw = W32S_APP2WINE(MAKELONG(DX_reg(context), CX_reg(context)), offset);
 826         if (dw < 0x10000)
 827             /* app wants to access lower 64K of DOS memory, map it in now */
 828             DOSMEM_Init(TRUE);
 829         SetSelectorBase(BX_reg(context), dw);
 830         break;
 831
 832     case 0x0008:  /* Set selector limit */
 833         TRACE("set selector limit (0x%04x,0x%08lx)\n",BX_reg(context),MAKELONG(DX_reg(context),CX_reg(context)));
 834         dw = MAKELONG( DX_reg(context), CX_reg(context) );
 835         SetSelectorLimit16( BX_reg(context), dw );
 836         break;
 837
 838     case 0x0009:  /* Set selector access rights */
 839         TRACE("set selector access rights(0x%04x,0x%04x)\n",BX_reg(context),CX_reg(context));
 840         SelectorAccessRights16( BX_reg(context), 1, CX_reg(context) );
 841         break;
 842
 843     case 0x000a:  /* Allocate selector alias */
 844         TRACE("allocate selector alias (0x%04x)\n",BX_reg(context));
 845         if (!(AX_reg(context) = AllocCStoDSAlias16( BX_reg(context) )))
 846         {
 847             AX_reg(context) = 0x8011;  /* descriptor unavailable */
 848             SET_CFLAG(context);
 849         }
 850         break;
 851
 852     case 0x000b:  /* Get descriptor */
 853         TRACE("get descriptor (0x%04x)\n",BX_reg(context));
 854         {
 855             ldt_entry entry;
 856             LDT_GetEntry( SELECTOR_TO_ENTRY( BX_reg(context) ), &entry );
 857             entry.base = W32S_WINE2APP(entry.base, offset);
 858
 859             /* FIXME: should use ES:EDI for 32-bit clients */
 860             LDT_EntryToBytes( PTR_SEG_OFF_TO_LIN( context->SegEs,
 861                                                   DI_reg(context) ), &entry );
 862         }
 863         break;
 864
 865     case 0x000c:  /* Set descriptor */
 866         TRACE("set descriptor (0x%04x)\n",BX_reg(context));
 867         {
 868             ldt_entry entry;
 869             LDT_BytesToEntry( PTR_SEG_OFF_TO_LIN( context->SegEs,
 870                                                   DI_reg(context) ), &entry );
 871             entry.base = W32S_APP2WINE(entry.base, offset);
 872             LDT_SetEntry( SELECTOR_TO_ENTRY( BX_reg(context) ), &entry );
 873         }
 874         break;
 875
 876     case 0x000d:  /* Allocate specific LDT descriptor */
 877         FIXME("allocate descriptor (0x%04x), stub!\n",BX_reg(context));
 878         AX_reg(context) = 0x8011; /* descriptor unavailable */
 879         SET_CFLAG(context);
 880         break;
 881     case 0x0100:  /* Allocate DOS memory block */
 882         TRACE("allocate DOS memory block (0x%x paragraphs)\n",BX_reg(context));
 883         dw = GlobalDOSAlloc16((DWORD)BX_reg(context)<<4);
 884         if (dw) {
 885             AX_reg(context) = HIWORD(dw);
 886             DX_reg(context) = LOWORD(dw);
 887         } else {
 888             AX_reg(context) = 0x0008; /* insufficient memory */
 889             BX_reg(context) = DOSMEM_Available()>>4;
 890             SET_CFLAG(context);
 891         }
 892         break;
 893     case 0x0101:  /* Free DOS memory block */
 894         TRACE("free DOS memory block (0x%04x)\n",DX_reg(context));
 895         dw = GlobalDOSFree16(DX_reg(context));
 896         if (!dw) {
 897             AX_reg(context) = 0x0009; /* memory block address invalid */
 898             SET_CFLAG(context);
 899         }
 900         break;
 901     case 0x0200: /* get real mode interrupt vector */
 902         FIXME("get realmode interupt vector(0x%02x) unimplemented.\n",
 903               BL_reg(context));
 904         SET_CFLAG(context);
 905         break;
 906     case 0x0201: /* set real mode interrupt vector */
 907         FIXME("set realmode interupt vector(0x%02x,0x%04x:0x%04x) unimplemented\n", BL_reg(context),CX_reg(context),DX_reg(context));
 908         SET_CFLAG(context);
 909         break;
 910     case 0x0204:  /* Get protected mode interrupt vector */
 911         TRACE("get protected mode interrupt handler (0x%02x), stub!\n",BL_reg(context));
 912         dw = (DWORD)INT_GetPMHandler( BL_reg(context) );
 913         CX_reg(context) = HIWORD(dw);
 914         DX_reg(context) = LOWORD(dw);
 915         break;
 916
 917     case 0x0205:  /* Set protected mode interrupt vector */
 918         TRACE("set protected mode interrupt handler (0x%02x,%p), stub!\n",
 919             BL_reg(context),PTR_SEG_OFF_TO_LIN(CX_reg(context),DX_reg(context)));
 920         INT_SetPMHandler( BL_reg(context),
 921                           (FARPROC16)PTR_SEG_OFF_TO_SEGPTR( CX_reg(context),
 922                                                             DX_reg(context) ));
 923         break;
 924
 925     case 0x0300:  /* Simulate real mode interrupt */
 926         CallRMInt( context );
 927         break;
 928
 929     case 0x0301:  /* Call real mode procedure with far return */
 930         CallRMProc( context, FALSE );
 931         break;
 932
 933     case 0x0302:  /* Call real mode procedure with interrupt return */
 934         CallRMProc( context, TRUE );
 935         break;
 936
 937     case 0x0303:  /* Allocate Real Mode Callback Address */
 938         AllocRMCB( context );
 939         break;
 940
 941     case 0x0304:  /* Free Real Mode Callback Address */
 942         FreeRMCB( context );
 943         break;
 944
 945     case 0x0305:  /* Get State Save/Restore Addresses */
 946         TRACE("get state save/restore addresses\n");
 947         /* we probably won't need this kind of state saving */
 948         AX_reg(context) = 0;
 949         /* real mode: just point to the lret */
 950         BX_reg(context) = DOSMEM_wrap_seg;
 951         context->Ecx = 2;
 952         /* protected mode: don't have any handler yet... */
 953         FIXME("no protected-mode dummy state save/restore handler yet\n");
 954         SI_reg(context) = 0;
 955         context->Edi = 0;
 956         break;
 957
 958     case 0x0306:  /* Get Raw Mode Switch Addresses */
 959         TRACE("get raw mode switch addresses\n");
 960         /* real mode, point to standard DPMI return wrapper */
 961         BX_reg(context) = DOSMEM_wrap_seg;
 962         context->Ecx = 0;
 963         /* protected mode, point to DPMI call wrapper */
 964         SI_reg(context) = DOSMEM_dpmi_sel;
 965         context->Edi = 8; /* offset of the INT 0x31 call */
 966         break;
 967     case 0x0400:  /* Get DPMI version */
 968         TRACE("get DPMI version\n");
 969         {
 970             SYSTEM_INFO si;
 971
 972             GetSystemInfo(&si);
 973             AX_reg(context) = 0x005a;  /* DPMI version 0.90 */
 974             BX_reg(context) = 0x0005;  /* Flags: 32-bit, virtual memory */
 975             CL_reg(context) = si.wProcessorLevel;
 976             DX_reg(context) = 0x0102;  /* Master/slave interrupt controller base*/
 977             break;
 978         }
 979     case 0x0500:  /* Get free memory information */
 980         TRACE("get free memory information\n");
 981         {
 982             MEMMANINFO mmi;
 983
 984             mmi.dwSize = sizeof(mmi);
 985             MemManInfo16(&mmi);
 986             ptr = (BYTE *)PTR_SEG_OFF_TO_LIN(context->SegEs,DI_reg(context));
 987             /* the layout is just the same as MEMMANINFO, but without
 988              * the dwSize entry.
 989              */
 990             memcpy(ptr,((char*)&mmi)+4,sizeof(mmi)-4);
 991             break;
 992         }
 993     case 0x0501:  /* Allocate memory block */
 994         TRACE("allocate memory block (%ld)\n",MAKELONG(CX_reg(context),BX_reg(context)));
 995         if (!(ptr = (BYTE *)DPMI_xalloc(MAKELONG(CX_reg(context), BX_reg(context)))))
 996         {
 997             AX_reg(context) = 0x8012;  /* linear memory not available */
 998             SET_CFLAG(context);
 999         } else {
1000             BX_reg(context) = SI_reg(context) = HIWORD(W32S_WINE2APP(ptr, offset));
1001             CX_reg(context) = DI_reg(context) = LOWORD(W32S_WINE2APP(ptr, offset));
1002         }
1003         break;
1004
1005     case 0x0502:  /* Free memory block */
1006         TRACE("free memory block (0x%08lx)\n",
1007                      W32S_APP2WINE(MAKELONG(DI_reg(context),SI_reg(context)), offset));
1008         DPMI_xfree( (void *)W32S_APP2WINE(MAKELONG(DI_reg(context),
1009                                                SI_reg(context)), offset) );
1010         break;
1011
1012     case 0x0503:  /* Resize memory block */
1013         TRACE("resize memory block (0x%08lx,%ld)\n",
1014                      W32S_APP2WINE(MAKELONG(DI_reg(context),SI_reg(context)), offset),
1015                      MAKELONG(CX_reg(context),BX_reg(context)));
1016         if (!(ptr = (BYTE *)DPMI_xrealloc(
1017                 (void *)W32S_APP2WINE(MAKELONG(DI_reg(context),SI_reg(context)), offset),
1018                 MAKELONG(CX_reg(context),BX_reg(context)))))
1019         {
1020             AX_reg(context) = 0x8012;  /* linear memory not available */
1021             SET_CFLAG(context);
1022         } else {
1023             BX_reg(context) = SI_reg(context) = HIWORD(W32S_WINE2APP(ptr, offset));
1024             CX_reg(context) = DI_reg(context) = LOWORD(W32S_WINE2APP(ptr, offset));
1025         }
1026         break;
1027
1028     case 0x0507:  /* Modify page attributes */
1029         FIXME("modify page attributes unimplemented\n");
1030         break;  /* Just ignore it */
1031
1032     case 0x0600:  /* Lock linear region */
1033         FIXME("lock linear region unimplemented\n");
1034         break;  /* Just ignore it */
1035
1036     case 0x0601:  /* Unlock linear region */
1037         FIXME("unlock linear region unimplemented\n");
1038         break;  /* Just ignore it */
1039
1040     case 0x0602:  /* Unlock real-mode region */
1041         FIXME("unlock realmode region unimplemented\n");
1042         break;  /* Just ignore it */
1043
1044     case 0x0603:  /* Lock real-mode region */
1045         FIXME("lock realmode region unimplemented\n");
1046         break;  /* Just ignore it */
1047
1048     case 0x0604:  /* Get page size */
1049         TRACE("get pagesize\n");
1050         BX_reg(context) = 0;
1051         CX_reg(context) = VIRTUAL_GetPageSize();
1052         break;
1053
1054     case 0x0702:  /* Mark page as demand-paging candidate */
1055         FIXME("mark page as demand-paging candidate\n");
1056         break;  /* Just ignore it */
1057
1058     case 0x0703:  /* Discard page contents */
1059         FIXME("discard page contents\n");
1060         break;  /* Just ignore it */
1061
1062      case 0x0800:  /* Physical address mapping */
1063         FIXME("map real to linear (0x%08lx)\n",MAKELONG(CX_reg(context),BX_reg(context)));
1064          if(!(ptr=DOSMEM_MapRealToLinear(MAKELONG(CX_reg(context),BX_reg(context)))))
1065          {
1066              AX_reg(context) = 0x8021;
1067              SET_CFLAG(context);
1068          }
1069          else
1070          {
1071              BX_reg(context) = HIWORD(W32S_WINE2APP(ptr, offset));
1072              CX_reg(context) = LOWORD(W32S_WINE2APP(ptr, offset));
1073              RESET_CFLAG(context);
1074          }
1075          break;
1076
1077     default:
1078         INT_BARF( context, 0x31 );
1079         AX_reg(context) = 0x8001;  /* unsupported function */
1080         SET_CFLAG(context);
1081         break;
1082     }
1083
1084 }