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"
29 WINE_DEFAULT_DEBUG_CHANNEL(int);
30 WINE_DECLARE_DEBUG_CHANNEL(io);
34 inline static void add_stack( CONTEXT86 *context, int offset )
36 if (ISV86(context) || !IS_SELECTOR_32BIT(context->SegSs))
37 ADD_LOWORD( context->Esp, offset );
39 context->Esp += offset;
42 inline static void *make_ptr( CONTEXT86 *context, DWORD seg, DWORD off, int long_addr )
44 if (ISV86(context)) return PTR_REAL_TO_LIN( seg, off );
45 if (IS_SELECTOR_SYSTEM(seg)) return (void *)off;
46 if (!long_addr) off = LOWORD(off);
47 return MapSL( MAKESEGPTR( seg, 0 ) ) + off;
50 inline static void *get_stack( CONTEXT86 *context )
53 return PTR_REAL_TO_LIN( context->SegSs, context->Esp );
54 if (IS_SELECTOR_SYSTEM(context->SegSs))
55 return (void *)context->Esp;
56 if (IS_SELECTOR_32BIT(context->SegSs))
57 return MapSL( MAKESEGPTR( context->SegSs, 0 ) ) + context->Esp;
58 return MapSL( MAKESEGPTR( context->SegSs, LOWORD(context->Esp) ) );
61 /***********************************************************************
62 * INSTR_ReplaceSelector
64 * Try to replace an invalid selector by a valid one.
65 * The only selector where it is allowed to do "mov ax,40;mov es,ax"
66 * is the so called 'bimodal' selector 0x40, which points to the BIOS
67 * data segment. Used by (at least) Borland products (and programs compiled
68 * using Borland products).
70 * See Undocumented Windows, Chapter 5, __0040.
72 static BOOL INSTR_ReplaceSelector( CONTEXT86 *context, WORD *sel )
74 extern char Call16_Start, Call16_End;
76 if (IS_SELECTOR_SYSTEM(context->SegCs))
77 if ( (char *)context->Eip >= &Call16_Start
78 && (char *)context->Eip < &Call16_End )
80 /* Saved selector may have become invalid when the relay code */
81 /* tries to restore it. We simply clear it. */
88 static WORD sys_timer = 0;
90 sys_timer = CreateSystemTimer( 55, DOSMEM_Tick );
91 *sel = DOSMEM_BiosDataSeg;
94 if (!IS_SELECTOR_SYSTEM(*sel) && !IS_SELECTOR_FREE(*sel))
95 ERR("Got protection fault on valid selector, maybe your kernel is too old?\n" );
96 return FALSE; /* Can't replace selector, crashdump */
100 /***********************************************************************
101 * INSTR_GetOperandAddr
103 * Return the address of an instruction operand (from the mod/rm byte).
105 static BYTE *INSTR_GetOperandAddr( CONTEXT86 *context, BYTE *instr,
106 int long_addr, int segprefix, int *len )
108 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) || IS_SELECTOR_FREE(seg)) return NULL;
251 if (wine_ldt_copy.limit[seg >> 3] < (base + (index << ss))) return NULL;
252 return MapSL( MAKESEGPTR( seg, 0 ) ) + base + (index << ss);
257 /***********************************************************************
260 * Emulate the LDS (and LES,LFS,etc.) instruction.
262 static BOOL INSTR_EmulateLDS( CONTEXT86 *context, BYTE *instr, int long_op,
263 int long_addr, int segprefix, int *len )
266 BYTE *regmodrm = instr + 1 + (*instr == 0x0f);
267 BYTE *addr = INSTR_GetOperandAddr( context, regmodrm,
268 long_addr, segprefix, len );
270 return FALSE; /* Unable to emulate it */
271 seg = *(WORD *)(addr + (long_op ? 4 : 2));
273 if (!INSTR_ReplaceSelector( context, &seg ))
274 return FALSE; /* Unable to emulate it */
276 /* Now store the offset in the correct register */
278 switch((*regmodrm >> 3) & 7)
281 if (long_op) context->Eax = *(DWORD *)addr;
282 else SET_LOWORD(context->Eax,*(WORD *)addr);
285 if (long_op) context->Ecx = *(DWORD *)addr;
286 else SET_LOWORD(context->Ecx,*(WORD *)addr);
289 if (long_op) context->Edx = *(DWORD *)addr;
290 else SET_LOWORD(context->Edx,*(WORD *)addr);
293 if (long_op) context->Ebx = *(DWORD *)addr;
294 else SET_LOWORD(context->Ebx,*(WORD *)addr);
297 if (long_op) context->Esp = *(DWORD *)addr;
298 else SET_LOWORD(context->Esp,*(WORD *)addr);
301 if (long_op) context->Ebp = *(DWORD *)addr;
302 else SET_LOWORD(context->Ebp,*(WORD *)addr);
305 if (long_op) context->Esi = *(DWORD *)addr;
306 else SET_LOWORD(context->Esi,*(WORD *)addr);
309 if (long_op) context->Edi = *(DWORD *)addr;
310 else SET_LOWORD(context->Edi,*(WORD *)addr);
314 /* Store the correct segment in the segment register */
318 case 0xc4: context->SegEs = seg; break; /* les */
319 case 0xc5: context->SegDs = seg; break; /* lds */
320 case 0x0f: switch(instr[1])
322 case 0xb2: context->SegSs = seg; break; /* lss */
323 case 0xb4: context->SegFs = seg; break; /* lfs */
324 case 0xb5: context->SegGs = seg; break; /* lgs */
329 /* Add the opcode size to the total length */
331 *len += 1 + (*instr == 0x0f);
335 /***********************************************************************
338 * input on a I/O port
340 static DWORD INSTR_inport( WORD port, int size, CONTEXT86 *context )
342 DWORD res = IO_inport( port, size );
348 DPRINTF( "0x%x < %02x @ %04x:%04x\n", port, LOBYTE(res),
349 (WORD)context->SegCs, LOWORD(context->Eip));
352 DPRINTF( "0x%x < %04x @ %04x:%04x\n", port, LOWORD(res),
353 (WORD)context->SegCs, LOWORD(context->Eip));
356 DPRINTF( "0x%x < %08lx @ %04x:%04x\n", port, res,
357 (WORD)context->SegCs, LOWORD(context->Eip));
365 /***********************************************************************
368 * output on a I/O port
370 static void INSTR_outport( WORD port, int size, DWORD val, CONTEXT86 *context )
372 IO_outport( port, size, val );
378 DPRINTF("0x%x > %02x @ %04x:%04x\n", port, LOBYTE(val),
379 (WORD)context->SegCs, LOWORD(context->Eip));
382 DPRINTF("0x%x > %04x @ %04x:%04x\n", port, LOWORD(val),
383 (WORD)context->SegCs, LOWORD(context->Eip));
386 DPRINTF("0x%x > %08lx @ %04x:%04x\n", port, val,
387 (WORD)context->SegCs, LOWORD(context->Eip));
394 /***********************************************************************
395 * INSTR_EmulateInstruction
397 * Emulate a privileged instruction. Returns TRUE if emulation successful.
399 BOOL INSTR_EmulateInstruction( CONTEXT86 *context )
401 int prefix, segprefix, prefixlen, len, repX, long_op, long_addr;
405 long_op = long_addr = (!ISV86(context) && IS_SELECTOR_32BIT(context->SegCs));
406 instr = make_ptr( context, context->SegCs, context->Eip, TRUE );
407 if (!instr) return FALSE;
409 /* First handle any possible prefix */
411 segprefix = -1; /* no prefix */
420 segprefix = context->SegCs;
423 segprefix = context->SegSs;
426 segprefix = context->SegDs;
429 segprefix = context->SegEs;
432 segprefix = context->SegFs;
435 segprefix = context->SegGs;
438 long_op = !long_op; /* opcode size prefix */
441 long_addr = !long_addr; /* addr size prefix */
443 case 0xf0: /* lock */
445 case 0xf2: /* repne */
448 case 0xf3: /* repe */
452 prefix = 0; /* no more prefixes */
462 /* Now look at the actual instruction */
466 case 0x07: /* pop es */
467 case 0x17: /* pop ss */
468 case 0x1f: /* pop ds */
470 WORD seg = *(WORD *)get_stack( context );
471 if (INSTR_ReplaceSelector( context, &seg ))
475 case 0x07: context->SegEs = seg; break;
476 case 0x17: context->SegSs = seg; break;
477 case 0x1f: context->SegDs = seg; break;
479 add_stack(context, long_op ? 4 : 2);
480 context->Eip += prefixlen + 1;
484 break; /* Unable to emulate it */
486 case 0x0f: /* extended instruction */
489 case 0x22: /* mov eax, crX */
492 ERR("mov eax,cr0 at 0x%08lx, EAX=0x%08lx\n",
493 context->Eip,context->Eax );
494 context->Eip += prefixlen+3;
497 break; /*fallthrough to bad instruction handling */
499 break; /*fallthrough to bad instruction handling */
500 case 0x20: /* mov crX, eax */
502 case 0xe0: /* mov cr4, eax */
503 /* CR4 register . See linux/arch/i386/mm/init.c, X86_CR4_ defs
504 * bit 0: VME Virtual Mode Exception ?
505 * bit 1: PVI Protected mode Virtual Interrupt
506 * bit 2: TSD Timestamp disable
507 * bit 3: DE Debugging extensions
508 * bit 4: PSE Page size extensions
509 * bit 5: PAE Physical address extension
510 * bit 6: MCE Machine check enable
511 * bit 7: PGE Enable global pages
512 * bit 8: PCE Enable performance counters at IPL3
514 ERR("mov cr4,eax at 0x%08lx\n",context->Eip);
516 context->Eip += prefixlen+3;
518 case 0xc0: /* mov cr0, eax */
519 ERR("mov cr0,eax at 0x%08lx\n",context->Eip);
520 context->Eax = 0x10; /* FIXME: set more bits ? */
521 context->Eip += prefixlen+3;
523 default: /* fallthrough to illegal instruction */
526 /* fallthrough to illegal instruction */
528 case 0xa1: /* pop fs */
530 WORD seg = *(WORD *)get_stack( context );
531 if (INSTR_ReplaceSelector( context, &seg ))
533 context->SegFs = seg;
534 add_stack(context, long_op ? 4 : 2);
535 context->Eip += prefixlen + 2;
540 case 0xa9: /* pop gs */
542 WORD seg = *(WORD *)get_stack( context );
543 if (INSTR_ReplaceSelector( context, &seg ))
545 context->SegGs = seg;
546 add_stack(context, long_op ? 4 : 2);
547 context->Eip += prefixlen + 2;
552 case 0xb2: /* lss addr,reg */
553 case 0xb4: /* lfs addr,reg */
554 case 0xb5: /* lgs addr,reg */
555 if (INSTR_EmulateLDS( context, instr, long_op,
556 long_addr, segprefix, &len ))
558 context->Eip += prefixlen + len;
563 break; /* Unable to emulate it */
565 case 0x6c: /* insb */
566 case 0x6d: /* insw/d */
567 case 0x6e: /* outsb */
568 case 0x6f: /* outsw/d */
570 int typ = *instr; /* Just in case it's overwritten. */
571 int outp = (typ >= 0x6e);
572 unsigned long count = repX ?
573 (long_addr ? context->Ecx : LOWORD(context->Ecx)) : 1;
574 int opsize = (typ & 1) ? (long_op ? 4 : 2) : 1;
575 int step = (context->EFlags & 0x400) ? -opsize : +opsize;
576 int seg = outp ? context->SegDs : context->SegEs; /* FIXME: is this right? */
579 /* FIXME: Check segment readable. */
582 /* FIXME: Check segment writeable. */
587 if (long_addr) context->Ecx = 0;
588 else SET_LOWORD(context->Ecx,0);
594 WORD dx = LOWORD(context->Edx);
597 data = make_ptr( context, seg, context->Esi, long_addr );
598 if (long_addr) context->Esi += step;
599 else ADD_LOWORD(context->Esi,step);
603 data = make_ptr( context, seg, context->Edi, long_addr );
604 if (long_addr) context->Edi += step;
605 else ADD_LOWORD(context->Edi,step);
611 *(BYTE *)data = INSTR_inport( dx, 1, context );
615 *(DWORD *)data = INSTR_inport( dx, 4, context );
617 *(WORD *)data = INSTR_inport( dx, 2, context );
620 INSTR_outport( dx, 1, *(BYTE *)data, context );
624 INSTR_outport( dx, 4, *(DWORD *)data, context );
626 INSTR_outport( dx, 2, *(WORD *)data, context );
630 context->Eip += prefixlen + 1;
634 case 0x8e: /* mov XX,segment_reg */
637 BYTE *addr = INSTR_GetOperandAddr(context, instr + 1,
638 long_addr, segprefix, &len );
640 break; /* Unable to emulate it */
642 if (!INSTR_ReplaceSelector( context, &seg ))
643 break; /* Unable to emulate it */
645 switch((instr[1] >> 3) & 7)
648 context->SegEs = seg;
649 context->Eip += prefixlen + len + 1;
654 context->SegSs = seg;
655 context->Eip += prefixlen + len + 1;
658 context->SegDs = seg;
659 context->Eip += prefixlen + len + 1;
662 context->SegFs = seg;
663 context->Eip += prefixlen + len + 1;
666 context->SegGs = seg;
667 context->Eip += prefixlen + len + 1;
674 break; /* Unable to emulate it */
676 case 0xc4: /* les addr,reg */
677 case 0xc5: /* lds addr,reg */
678 if (INSTR_EmulateLDS( context, instr, long_op,
679 long_addr, segprefix, &len ))
681 context->Eip += prefixlen + len;
684 break; /* Unable to emulate it */
686 case 0xcd: /* int <XX> */
689 ERR("int xx from 32-bit code is not supported.\n");
690 break; /* Unable to emulate it */
694 FARPROC16 addr = INT_GetPMHandler( instr[1] );
695 WORD *stack = get_stack( context );
698 FIXME("no handler for interrupt %02x, ignoring it\n", instr[1]);
699 context->Eip += prefixlen + 2;
702 /* Push the flags and return address on the stack */
703 *(--stack) = LOWORD(context->EFlags);
704 *(--stack) = context->SegCs;
705 *(--stack) = LOWORD(context->Eip) + prefixlen + 2;
706 add_stack(context, -3 * sizeof(WORD));
707 /* Jump to the interrupt handler */
708 context->SegCs = HIWORD(addr);
709 context->Eip = LOWORD(addr);
713 case 0xcf: /* iret */
716 DWORD *stack = get_stack( context );
717 context->Eip = *stack++;
718 context->SegCs = *stack++;
719 context->EFlags = *stack;
720 add_stack(context, 3*sizeof(DWORD)); /* Pop the return address and flags */
724 WORD *stack = get_stack( context );
725 context->Eip = *stack++;
726 context->SegCs = *stack++;
727 SET_LOWORD(context->EFlags,*stack);
728 add_stack(context, 3*sizeof(WORD)); /* Pop the return address and flags */
732 case 0xe4: /* inb al,XX */
733 SET_LOBYTE(context->Eax,INSTR_inport( instr[1], 1, context ));
734 context->Eip += prefixlen + 2;
737 case 0xe5: /* in (e)ax,XX */
739 context->Eax = INSTR_inport( instr[1], 4, context );
741 SET_LOWORD(context->Eax, INSTR_inport( instr[1], 2, context ));
742 context->Eip += prefixlen + 2;
745 case 0xe6: /* outb XX,al */
746 INSTR_outport( instr[1], 1, LOBYTE(context->Eax), context );
747 context->Eip += prefixlen + 2;
750 case 0xe7: /* out XX,(e)ax */
752 INSTR_outport( instr[1], 4, context->Eax, context );
754 INSTR_outport( instr[1], 2, LOWORD(context->Eax), context );
755 context->Eip += prefixlen + 2;
758 case 0xec: /* inb al,dx */
759 SET_LOBYTE(context->Eax, INSTR_inport( LOWORD(context->Edx), 1, context ) );
760 context->Eip += prefixlen + 1;
763 case 0xed: /* in (e)ax,dx */
765 context->Eax = INSTR_inport( LOWORD(context->Edx), 4, context );
767 SET_LOWORD(context->Eax, INSTR_inport( LOWORD(context->Edx), 2, context ));
768 context->Eip += prefixlen + 1;
771 case 0xee: /* outb dx,al */
772 INSTR_outport( LOWORD(context->Edx), 1, LOBYTE(context->Eax), context );
773 context->Eip += prefixlen + 1;
776 case 0xef: /* out dx,(e)ax */
778 INSTR_outport( LOWORD(context->Edx), 4, context->Eax, context );
780 INSTR_outport( LOWORD(context->Edx), 2, LOWORD(context->Eax), context );
781 context->Eip += prefixlen + 1;
784 case 0xfa: /* cli, ignored */
785 context->Eip += prefixlen + 1;
788 case 0xfb: /* sti, ignored */
789 context->Eip += prefixlen + 1;
794 /* Check for Win16 __GP handler */
795 gpHandler = HasGPHandler16( MAKESEGPTR( context->SegCs, context->Eip ) );
798 WORD *stack = get_stack( context );
799 *--stack = context->SegCs;
800 *--stack = context->Eip;
801 add_stack(context, -2*sizeof(WORD));
803 context->SegCs = SELECTOROF( gpHandler );
804 context->Eip = OFFSETOF( gpHandler );
807 return FALSE; /* Unable to emulate it */
810 #endif /* __i386__ */