2 * Emulation of privileged instructions
4 * Copyright 1995 Alexandre Julliard
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.
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.
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
23 #include "wine/winuser16.h"
26 #include "selectors.h"
27 #include "wine/debug.h"
30 WINE_DEFAULT_DEBUG_CHANNEL(int);
31 WINE_DECLARE_DEBUG_CHANNEL(io);
35 /* macros to set parts of a DWORD */
36 #define SET_LOWORD(dw,val) ((dw) = ((dw) & 0xffff0000) | LOWORD(val))
37 #define SET_LOBYTE(dw,val) ((dw) = ((dw) & 0xffffff00) | LOBYTE(val))
38 #define ADD_LOWORD(dw,val) ((dw) = ((dw) & 0xffff0000) | LOWORD((DWORD)(dw)+(val)))
40 inline static void add_stack( CONTEXT86 *context, int offset )
42 if (ISV86(context) || !IS_SELECTOR_32BIT(context->SegSs))
43 ADD_LOWORD( context->Esp, offset );
45 context->Esp += offset;
48 inline static void *make_ptr( CONTEXT86 *context, DWORD seg, DWORD off, int long_addr )
50 if (ISV86(context)) return PTR_REAL_TO_LIN( seg, off );
51 if (IS_SELECTOR_SYSTEM(seg)) return (void *)off;
52 if (!long_addr) off = LOWORD(off);
53 return (char *) MapSL( MAKESEGPTR( seg, 0 ) ) + off;
56 inline static void *get_stack( CONTEXT86 *context )
58 if (ISV86(context)) return PTR_REAL_TO_LIN( context->SegSs, context->Esp );
59 return wine_ldt_get_ptr( context->SegSs, context->Esp );
62 /***********************************************************************
63 * INSTR_ReplaceSelector
65 * Try to replace an invalid selector by a valid one.
66 * The only selector where it is allowed to do "mov ax,40;mov es,ax"
67 * is the so called 'bimodal' selector 0x40, which points to the BIOS
68 * data segment. Used by (at least) Borland products (and programs compiled
69 * using Borland products).
71 * See Undocumented Windows, Chapter 5, __0040.
73 static BOOL INSTR_ReplaceSelector( CONTEXT86 *context, WORD *sel )
75 extern char Call16_Start, Call16_End;
77 if (IS_SELECTOR_SYSTEM(context->SegCs))
78 if ( (char *)context->Eip >= &Call16_Start
79 && (char *)context->Eip < &Call16_End )
81 /* Saved selector may have become invalid when the relay code */
82 /* tries to restore it. We simply clear it. */
89 static WORD sys_timer = 0;
91 sys_timer = CreateSystemTimer( 55, DOSMEM_Tick );
92 *sel = DOSMEM_BiosDataSeg;
95 return FALSE; /* Can't replace selector, crashdump */
99 /***********************************************************************
100 * INSTR_GetOperandAddr
102 * Return the address of an instruction operand (from the mod/rm byte).
104 static BYTE *INSTR_GetOperandAddr( CONTEXT86 *context, BYTE *instr,
105 int long_addr, int segprefix, int *len )
107 int mod, rm, base, index = 0, ss = 0, seg = 0, off;
110 #define GET_VAL(val,type) \
111 { *val = *(type *)instr; instr += sizeof(type); *len += sizeof(type); }
114 GET_VAL( &mod, BYTE );
122 case 0: return (BYTE *)&context->Eax;
123 case 1: return (BYTE *)&context->Ecx;
124 case 2: return (BYTE *)&context->Edx;
125 case 3: return (BYTE *)&context->Ebx;
126 case 4: return (BYTE *)&context->Esp;
127 case 5: return (BYTE *)&context->Ebp;
128 case 6: return (BYTE *)&context->Esi;
129 case 7: return (BYTE *)&context->Edi;
138 GET_VAL( &sib, BYTE );
143 case 0: index = context->Eax; break;
144 case 1: index = context->Ecx; break;
145 case 2: index = context->Edx; break;
146 case 3: index = context->Ebx; break;
147 case 4: index = 0; break;
148 case 5: index = context->Ebp; break;
149 case 6: index = context->Esi; break;
150 case 7: index = context->Edi; break;
156 case 0: base = context->Eax; seg = context->SegDs; break;
157 case 1: base = context->Ecx; seg = context->SegDs; break;
158 case 2: base = context->Edx; seg = context->SegDs; break;
159 case 3: base = context->Ebx; seg = context->SegDs; break;
160 case 4: base = context->Esp; seg = context->SegSs; break;
161 case 5: base = context->Ebp; seg = context->SegSs; break;
162 case 6: base = context->Esi; seg = context->SegDs; break;
163 case 7: base = context->Edi; seg = context->SegDs; break;
168 if (rm == 5) /* special case: ds:(disp32) */
170 GET_VAL( &base, DWORD );
171 seg = context->SegDs;
175 case 1: /* 8-bit disp */
176 GET_VAL( &off, BYTE );
177 base += (signed char)off;
180 case 2: /* 32-bit disp */
181 GET_VAL( &off, DWORD );
182 base += (signed long)off;
186 else /* short address */
190 case 0: /* ds:(bx,si) */
191 base = LOWORD(context->Ebx) + LOWORD(context->Esi);
192 seg = context->SegDs;
194 case 1: /* ds:(bx,di) */
195 base = LOWORD(context->Ebx) + LOWORD(context->Edi);
196 seg = context->SegDs;
198 case 2: /* ss:(bp,si) */
199 base = LOWORD(context->Ebp) + LOWORD(context->Esi);
200 seg = context->SegSs;
202 case 3: /* ss:(bp,di) */
203 base = LOWORD(context->Ebp) + LOWORD(context->Edi);
204 seg = context->SegSs;
206 case 4: /* ds:(si) */
207 base = LOWORD(context->Esi);
208 seg = context->SegDs;
210 case 5: /* ds:(di) */
211 base = LOWORD(context->Edi);
212 seg = context->SegDs;
214 case 6: /* ss:(bp) */
215 base = LOWORD(context->Ebp);
216 seg = context->SegSs;
218 case 7: /* ds:(bx) */
219 base = LOWORD(context->Ebx);
220 seg = context->SegDs;
227 if (rm == 6) /* special case: ds:(disp16) */
229 GET_VAL( &base, WORD );
230 seg = context->SegDs;
234 case 1: /* 8-bit disp */
235 GET_VAL( &off, BYTE );
236 base += (signed char)off;
239 case 2: /* 16-bit disp */
240 GET_VAL( &off, WORD );
241 base += (signed short)off;
246 if (segprefix != -1) seg = segprefix;
248 /* Make sure the segment and offset are valid */
249 if (IS_SELECTOR_SYSTEM(seg)) return (BYTE *)(base + (index << ss));
250 if ((seg & 7) != 7) return NULL;
251 wine_ldt_get_entry( seg, &entry );
252 if (wine_ldt_is_empty( &entry )) return NULL;
253 if (wine_ldt_get_limit(&entry) < (base + (index << ss))) return NULL;
254 return (char *)wine_ldt_get_base(&entry) + base + (index << ss);
259 /***********************************************************************
262 * Emulate the LDS (and LES,LFS,etc.) instruction.
264 static BOOL INSTR_EmulateLDS( CONTEXT86 *context, BYTE *instr, int long_op,
265 int long_addr, int segprefix, int *len )
268 BYTE *regmodrm = instr + 1 + (*instr == 0x0f);
269 BYTE *addr = INSTR_GetOperandAddr( context, regmodrm,
270 long_addr, segprefix, len );
272 return FALSE; /* Unable to emulate it */
273 seg = *(WORD *)(addr + (long_op ? 4 : 2));
275 if (!INSTR_ReplaceSelector( context, &seg ))
276 return FALSE; /* Unable to emulate it */
278 /* Now store the offset in the correct register */
280 switch((*regmodrm >> 3) & 7)
283 if (long_op) context->Eax = *(DWORD *)addr;
284 else SET_LOWORD(context->Eax,*(WORD *)addr);
287 if (long_op) context->Ecx = *(DWORD *)addr;
288 else SET_LOWORD(context->Ecx,*(WORD *)addr);
291 if (long_op) context->Edx = *(DWORD *)addr;
292 else SET_LOWORD(context->Edx,*(WORD *)addr);
295 if (long_op) context->Ebx = *(DWORD *)addr;
296 else SET_LOWORD(context->Ebx,*(WORD *)addr);
299 if (long_op) context->Esp = *(DWORD *)addr;
300 else SET_LOWORD(context->Esp,*(WORD *)addr);
303 if (long_op) context->Ebp = *(DWORD *)addr;
304 else SET_LOWORD(context->Ebp,*(WORD *)addr);
307 if (long_op) context->Esi = *(DWORD *)addr;
308 else SET_LOWORD(context->Esi,*(WORD *)addr);
311 if (long_op) context->Edi = *(DWORD *)addr;
312 else SET_LOWORD(context->Edi,*(WORD *)addr);
316 /* Store the correct segment in the segment register */
320 case 0xc4: context->SegEs = seg; break; /* les */
321 case 0xc5: context->SegDs = seg; break; /* lds */
322 case 0x0f: switch(instr[1])
324 case 0xb2: context->SegSs = seg; break; /* lss */
325 case 0xb4: context->SegFs = seg; break; /* lfs */
326 case 0xb5: context->SegGs = seg; break; /* lgs */
331 /* Add the opcode size to the total length */
333 *len += 1 + (*instr == 0x0f);
337 /***********************************************************************
340 * input on a I/O port
342 static DWORD INSTR_inport( WORD port, int size, CONTEXT86 *context )
344 DWORD res = IO_inport( port, size );
350 DPRINTF( "0x%x < %02x @ %04x:%04x\n", port, LOBYTE(res),
351 (WORD)context->SegCs, LOWORD(context->Eip));
354 DPRINTF( "0x%x < %04x @ %04x:%04x\n", port, LOWORD(res),
355 (WORD)context->SegCs, LOWORD(context->Eip));
358 DPRINTF( "0x%x < %08lx @ %04x:%04x\n", port, res,
359 (WORD)context->SegCs, LOWORD(context->Eip));
367 /***********************************************************************
370 * output on a I/O port
372 static void INSTR_outport( WORD port, int size, DWORD val, CONTEXT86 *context )
374 IO_outport( port, size, val );
380 DPRINTF("0x%x > %02x @ %04x:%04x\n", port, LOBYTE(val),
381 (WORD)context->SegCs, LOWORD(context->Eip));
384 DPRINTF("0x%x > %04x @ %04x:%04x\n", port, LOWORD(val),
385 (WORD)context->SegCs, LOWORD(context->Eip));
388 DPRINTF("0x%x > %08lx @ %04x:%04x\n", port, val,
389 (WORD)context->SegCs, LOWORD(context->Eip));
396 /***********************************************************************
397 * INSTR_EmulateInstruction
399 * Emulate a privileged instruction. Returns TRUE if emulation successful.
401 BOOL INSTR_EmulateInstruction( CONTEXT86 *context )
403 int prefix, segprefix, prefixlen, len, repX, long_op, long_addr;
407 long_op = long_addr = (!ISV86(context) && IS_SELECTOR_32BIT(context->SegCs));
408 instr = make_ptr( context, context->SegCs, context->Eip, TRUE );
409 if (!instr) return FALSE;
411 /* First handle any possible prefix */
413 segprefix = -1; /* no prefix */
422 segprefix = context->SegCs;
425 segprefix = context->SegSs;
428 segprefix = context->SegDs;
431 segprefix = context->SegEs;
434 segprefix = context->SegFs;
437 segprefix = context->SegGs;
440 long_op = !long_op; /* opcode size prefix */
443 long_addr = !long_addr; /* addr size prefix */
445 case 0xf0: /* lock */
447 case 0xf2: /* repne */
450 case 0xf3: /* repe */
454 prefix = 0; /* no more prefixes */
464 /* Now look at the actual instruction */
468 case 0x07: /* pop es */
469 case 0x17: /* pop ss */
470 case 0x1f: /* pop ds */
472 WORD seg = *(WORD *)get_stack( context );
473 if (INSTR_ReplaceSelector( context, &seg ))
477 case 0x07: context->SegEs = seg; break;
478 case 0x17: context->SegSs = seg; break;
479 case 0x1f: context->SegDs = seg; break;
481 add_stack(context, long_op ? 4 : 2);
482 context->Eip += prefixlen + 1;
486 break; /* Unable to emulate it */
488 case 0x0f: /* extended instruction */
491 case 0x22: /* mov eax, crX */
494 ERR("mov eax,cr0 at 0x%08lx, EAX=0x%08lx\n",
495 context->Eip,context->Eax );
496 context->Eip += prefixlen+3;
499 break; /*fallthrough to bad instruction handling */
501 break; /*fallthrough to bad instruction handling */
502 case 0x20: /* mov crX, eax */
504 case 0xe0: /* mov cr4, eax */
505 /* CR4 register . See linux/arch/i386/mm/init.c, X86_CR4_ defs
506 * bit 0: VME Virtual Mode Exception ?
507 * bit 1: PVI Protected mode Virtual Interrupt
508 * bit 2: TSD Timestamp disable
509 * bit 3: DE Debugging extensions
510 * bit 4: PSE Page size extensions
511 * bit 5: PAE Physical address extension
512 * bit 6: MCE Machine check enable
513 * bit 7: PGE Enable global pages
514 * bit 8: PCE Enable performance counters at IPL3
516 ERR("mov cr4,eax at 0x%08lx\n",context->Eip);
518 context->Eip += prefixlen+3;
520 case 0xc0: /* mov cr0, eax */
521 ERR("mov cr0,eax at 0x%08lx\n",context->Eip);
522 context->Eax = 0x10; /* FIXME: set more bits ? */
523 context->Eip += prefixlen+3;
525 default: /* fallthrough to illegal instruction */
528 /* fallthrough to illegal instruction */
530 case 0xa1: /* pop fs */
532 WORD seg = *(WORD *)get_stack( context );
533 if (INSTR_ReplaceSelector( context, &seg ))
535 context->SegFs = seg;
536 add_stack(context, long_op ? 4 : 2);
537 context->Eip += prefixlen + 2;
542 case 0xa9: /* pop gs */
544 WORD seg = *(WORD *)get_stack( context );
545 if (INSTR_ReplaceSelector( context, &seg ))
547 context->SegGs = seg;
548 add_stack(context, long_op ? 4 : 2);
549 context->Eip += prefixlen + 2;
554 case 0xb2: /* lss addr,reg */
555 case 0xb4: /* lfs addr,reg */
556 case 0xb5: /* lgs addr,reg */
557 if (INSTR_EmulateLDS( context, instr, long_op,
558 long_addr, segprefix, &len ))
560 context->Eip += prefixlen + len;
565 break; /* Unable to emulate it */
567 case 0x6c: /* insb */
568 case 0x6d: /* insw/d */
569 case 0x6e: /* outsb */
570 case 0x6f: /* outsw/d */
572 int typ = *instr; /* Just in case it's overwritten. */
573 int outp = (typ >= 0x6e);
574 unsigned long count = repX ?
575 (long_addr ? context->Ecx : LOWORD(context->Ecx)) : 1;
576 int opsize = (typ & 1) ? (long_op ? 4 : 2) : 1;
577 int step = (context->EFlags & 0x400) ? -opsize : +opsize;
578 int seg = outp ? context->SegDs : context->SegEs; /* FIXME: is this right? */
581 /* FIXME: Check segment readable. */
584 /* FIXME: Check segment writeable. */
589 if (long_addr) context->Ecx = 0;
590 else SET_LOWORD(context->Ecx,0);
596 WORD dx = LOWORD(context->Edx);
599 data = make_ptr( context, seg, context->Esi, long_addr );
600 if (long_addr) context->Esi += step;
601 else ADD_LOWORD(context->Esi,step);
605 data = make_ptr( context, seg, context->Edi, long_addr );
606 if (long_addr) context->Edi += step;
607 else ADD_LOWORD(context->Edi,step);
613 *(BYTE *)data = INSTR_inport( dx, 1, context );
617 *(DWORD *)data = INSTR_inport( dx, 4, context );
619 *(WORD *)data = INSTR_inport( dx, 2, context );
622 INSTR_outport( dx, 1, *(BYTE *)data, context );
626 INSTR_outport( dx, 4, *(DWORD *)data, context );
628 INSTR_outport( dx, 2, *(WORD *)data, context );
632 context->Eip += prefixlen + 1;
636 case 0x8e: /* mov XX,segment_reg */
639 BYTE *addr = INSTR_GetOperandAddr(context, instr + 1,
640 long_addr, segprefix, &len );
642 break; /* Unable to emulate it */
644 if (!INSTR_ReplaceSelector( context, &seg ))
645 break; /* Unable to emulate it */
647 switch((instr[1] >> 3) & 7)
650 context->SegEs = seg;
651 context->Eip += prefixlen + len + 1;
656 context->SegSs = seg;
657 context->Eip += prefixlen + len + 1;
660 context->SegDs = seg;
661 context->Eip += prefixlen + len + 1;
664 context->SegFs = seg;
665 context->Eip += prefixlen + len + 1;
668 context->SegGs = seg;
669 context->Eip += prefixlen + len + 1;
676 break; /* Unable to emulate it */
678 case 0xc4: /* les addr,reg */
679 case 0xc5: /* lds addr,reg */
680 if (INSTR_EmulateLDS( context, instr, long_op,
681 long_addr, segprefix, &len ))
683 context->Eip += prefixlen + len;
686 break; /* Unable to emulate it */
688 case 0xcd: /* int <XX> */
689 if(!Dosvm.EmulateInterruptPM && !DPMI_LoadDosSystem())
690 ERR("could not initialize interrupt handling\n");
692 context->Eip += prefixlen + 2;
693 Dosvm.EmulateInterruptPM( context, instr[1] );
696 break; /* Unable to emulate it */
698 case 0xcf: /* iret */
701 DWORD *stack = get_stack( context );
702 context->Eip = *stack++;
703 context->SegCs = *stack++;
704 context->EFlags = *stack;
705 add_stack(context, 3*sizeof(DWORD)); /* Pop the return address and flags */
709 WORD *stack = get_stack( context );
710 context->Eip = *stack++;
711 context->SegCs = *stack++;
712 SET_LOWORD(context->EFlags,*stack);
713 add_stack(context, 3*sizeof(WORD)); /* Pop the return address and flags */
717 case 0xe4: /* inb al,XX */
718 SET_LOBYTE(context->Eax,INSTR_inport( instr[1], 1, context ));
719 context->Eip += prefixlen + 2;
722 case 0xe5: /* in (e)ax,XX */
724 context->Eax = INSTR_inport( instr[1], 4, context );
726 SET_LOWORD(context->Eax, INSTR_inport( instr[1], 2, context ));
727 context->Eip += prefixlen + 2;
730 case 0xe6: /* outb XX,al */
731 INSTR_outport( instr[1], 1, LOBYTE(context->Eax), context );
732 context->Eip += prefixlen + 2;
735 case 0xe7: /* out XX,(e)ax */
737 INSTR_outport( instr[1], 4, context->Eax, context );
739 INSTR_outport( instr[1], 2, LOWORD(context->Eax), context );
740 context->Eip += prefixlen + 2;
743 case 0xec: /* inb al,dx */
744 SET_LOBYTE(context->Eax, INSTR_inport( LOWORD(context->Edx), 1, context ) );
745 context->Eip += prefixlen + 1;
748 case 0xed: /* in (e)ax,dx */
750 context->Eax = INSTR_inport( LOWORD(context->Edx), 4, context );
752 SET_LOWORD(context->Eax, INSTR_inport( LOWORD(context->Edx), 2, context ));
753 context->Eip += prefixlen + 1;
756 case 0xee: /* outb dx,al */
757 INSTR_outport( LOWORD(context->Edx), 1, LOBYTE(context->Eax), context );
758 context->Eip += prefixlen + 1;
761 case 0xef: /* out dx,(e)ax */
763 INSTR_outport( LOWORD(context->Edx), 4, context->Eax, context );
765 INSTR_outport( LOWORD(context->Edx), 2, LOWORD(context->Eax), context );
766 context->Eip += prefixlen + 1;
769 case 0xfa: /* cli, ignored */
770 context->Eip += prefixlen + 1;
773 case 0xfb: /* sti, ignored */
774 context->Eip += prefixlen + 1;
779 /* Check for Win16 __GP handler */
780 gpHandler = HasGPHandler16( MAKESEGPTR( context->SegCs, context->Eip ) );
783 WORD *stack = get_stack( context );
784 *--stack = context->SegCs;
785 *--stack = context->Eip;
786 add_stack(context, -2*sizeof(WORD));
788 context->SegCs = SELECTOROF( gpHandler );
789 context->Eip = OFFSETOF( gpHandler );
792 return FALSE; /* Unable to emulate it */
795 #endif /* __i386__ */