2 * Emulation of priviledged instructions
4 * Copyright 1995 Alexandre Julliard
7 #include "wine/winuser16.h"
13 #include "selectors.h"
14 #include "debugtools.h"
16 DECLARE_DEBUG_CHANNEL(int)
17 DECLARE_DEBUG_CHANNEL(io
)
21 #define IS_SEL_32(context,seg) \
22 (ISV86(context) ? FALSE : IS_SELECTOR_32BIT(seg))
24 #define STACK_reg(context) \
25 (IS_SEL_32(context,SS_reg(context)) ? ESP_reg(context) : (DWORD)LOWORD(ESP_reg(context)))
27 #define ADD_STACK_reg(context,offset) \
28 do { if (IS_SEL_32(context,SS_reg(context))) ESP_reg(context) += (offset); \
29 else ADD_LOWORD(ESP_reg(context),(offset)); } while(0)
31 #define MAKE_PTR(seg,off) \
32 (IS_SELECTOR_SYSTEM(seg) ? (void *)(off) : PTR_SEG_OFF_TO_LIN(seg,off))
34 #define MK_PTR(context,seg,off) \
35 (ISV86(context) ? DOSMEM_MapRealToLinear(MAKELONG(off,seg)) \
38 #define STACK_PTR(context) \
40 DOSMEM_MapRealToLinear(MAKELONG(LOWORD(ESP_reg(context)),SS_reg(context))) : \
41 (IS_SELECTOR_SYSTEM(SS_reg(context)) ? (void *)ESP_reg(context) : \
42 (PTR_SEG_OFF_TO_LIN(SS_reg(context),STACK_reg(context)))))
44 /***********************************************************************
45 * INSTR_ReplaceSelector
47 * Try to replace an invalid selector by a valid one.
48 * The only selector where it is allowed to do "mov ax,40;mov es,ax"
49 * is the so called 'bimodal' selector 0x40, which points to the BIOS
50 * data segment. Used by (at least) Borland products (and programs compiled
51 * using Borland products).
53 * See Undocumented Windows, Chapter 5, __0040.
55 static BOOL
INSTR_ReplaceSelector( CONTEXT86
*context
, WORD
*sel
)
57 extern char Call16_Start
, Call16_End
;
59 if (IS_SELECTOR_SYSTEM(CS_reg(context
)))
60 if ( (char *)EIP_reg(context
) >= &Call16_Start
61 && (char *)EIP_reg(context
) < &Call16_End
)
63 /* Saved selector may have become invalid when the relay code */
64 /* tries to restore it. We simply clear it. */
71 static WORD sys_timer
= 0;
73 sys_timer
= CreateSystemTimer( 55, DOSMEM_Tick
);
74 *sel
= DOSMEM_BiosDataSeg
;
77 if (!IS_SELECTOR_SYSTEM(*sel
) && !IS_SELECTOR_FREE(*sel
))
78 ERR_(int)("Got protection fault on valid selector, maybe your kernel is too old?\n" );
79 return FALSE
; /* Can't replace selector, crashdump */
83 /***********************************************************************
84 * INSTR_GetOperandAddr
86 * Return the address of an instruction operand (from the mod/rm byte).
88 static BYTE
*INSTR_GetOperandAddr( CONTEXT86
*context
, BYTE
*instr
,
89 int long_addr
, int segprefix
, int *len
)
91 int mod
, rm
, base
, index
= 0, ss
= 0, seg
= 0, off
;
93 #define GET_VAL(val,type) \
94 { *val = *(type *)instr; instr += sizeof(type); *len += sizeof(type); }
97 GET_VAL( &mod
, BYTE
);
105 case 0: return (BYTE
*)&EAX_reg(context
);
106 case 1: return (BYTE
*)&ECX_reg(context
);
107 case 2: return (BYTE
*)&EDX_reg(context
);
108 case 3: return (BYTE
*)&EBX_reg(context
);
109 case 4: return (BYTE
*)&ESP_reg(context
);
110 case 5: return (BYTE
*)&EBP_reg(context
);
111 case 6: return (BYTE
*)&ESI_reg(context
);
112 case 7: return (BYTE
*)&EDI_reg(context
);
121 GET_VAL( &sib
, BYTE
);
126 case 0: index
= EAX_reg(context
); break;
127 case 1: index
= ECX_reg(context
); break;
128 case 2: index
= EDX_reg(context
); break;
129 case 3: index
= EBX_reg(context
); break;
130 case 4: index
= 0; break;
131 case 5: index
= EBP_reg(context
); break;
132 case 6: index
= ESI_reg(context
); break;
133 case 7: index
= EDI_reg(context
); break;
139 case 0: base
= EAX_reg(context
); seg
= DS_reg(context
); break;
140 case 1: base
= ECX_reg(context
); seg
= DS_reg(context
); break;
141 case 2: base
= EDX_reg(context
); seg
= DS_reg(context
); break;
142 case 3: base
= EBX_reg(context
); seg
= DS_reg(context
); break;
143 case 4: base
= ESP_reg(context
); seg
= SS_reg(context
); break;
144 case 5: base
= EBP_reg(context
); seg
= SS_reg(context
); break;
145 case 6: base
= ESI_reg(context
); seg
= DS_reg(context
); break;
146 case 7: base
= EDI_reg(context
); seg
= DS_reg(context
); break;
151 if (rm
== 5) /* special case: ds:(disp32) */
153 GET_VAL( &base
, DWORD
);
154 seg
= DS_reg(context
);
158 case 1: /* 8-bit disp */
159 GET_VAL( &off
, BYTE
);
160 base
+= (signed char)off
;
163 case 2: /* 32-bit disp */
164 GET_VAL( &off
, DWORD
);
165 base
+= (signed long)off
;
169 else /* short address */
173 case 0: /* ds:(bx,si) */
174 base
= LOWORD(EBX_reg(context
)) + LOWORD(ESI_reg(context
));
175 seg
= DS_reg(context
);
177 case 1: /* ds:(bx,di) */
178 base
= LOWORD(EBX_reg(context
)) + LOWORD(EDI_reg(context
));
179 seg
= DS_reg(context
);
181 case 2: /* ss:(bp,si) */
182 base
= LOWORD(EBP_reg(context
)) + LOWORD(ESI_reg(context
));
183 seg
= SS_reg(context
);
185 case 3: /* ss:(bp,di) */
186 base
= LOWORD(EBP_reg(context
)) + LOWORD(EDI_reg(context
));
187 seg
= SS_reg(context
);
189 case 4: /* ds:(si) */
190 base
= LOWORD(ESI_reg(context
));
191 seg
= DS_reg(context
);
193 case 5: /* ds:(di) */
194 base
= LOWORD(EDI_reg(context
));
195 seg
= DS_reg(context
);
197 case 6: /* ss:(bp) */
198 base
= LOWORD(EBP_reg(context
));
199 seg
= SS_reg(context
);
201 case 7: /* ds:(bx) */
202 base
= LOWORD(EBX_reg(context
));
203 seg
= DS_reg(context
);
210 if (rm
== 6) /* special case: ds:(disp16) */
212 GET_VAL( &base
, WORD
);
213 seg
= DS_reg(context
);
217 case 1: /* 8-bit disp */
218 GET_VAL( &off
, BYTE
);
219 base
+= (signed char)off
;
222 case 2: /* 16-bit disp */
223 GET_VAL( &off
, WORD
);
224 base
+= (signed short)off
;
229 if (segprefix
!= -1) seg
= segprefix
;
231 /* Make sure the segment and offset are valid */
232 if (IS_SELECTOR_SYSTEM(seg
)) return (BYTE
*)(base
+ (index
<< ss
));
233 if (((seg
& 7) != 7) || IS_SELECTOR_FREE(seg
)) return NULL
;
234 if (GET_SEL_LIMIT(seg
) < (base
+ (index
<< ss
))) return NULL
;
235 return (BYTE
*)PTR_SEG_OFF_TO_LIN( seg
, (base
+ (index
<< ss
)) );
240 /***********************************************************************
243 * Emulate the LDS (and LES,LFS,etc.) instruction.
245 static BOOL
INSTR_EmulateLDS( CONTEXT86
*context
, BYTE
*instr
, int long_op
,
246 int long_addr
, int segprefix
, int *len
)
249 BYTE
*regmodrm
= instr
+ 1 + (*instr
== 0x0f);
250 BYTE
*addr
= INSTR_GetOperandAddr( context
, regmodrm
,
251 long_addr
, segprefix
, len
);
253 return FALSE
; /* Unable to emulate it */
254 seg
= *(WORD
*)(addr
+ (long_op
? 4 : 2));
256 if (!INSTR_ReplaceSelector( context
, &seg
))
257 return FALSE
; /* Unable to emulate it */
259 /* Now store the offset in the correct register */
261 switch((*regmodrm
>> 3) & 7)
264 if (long_op
) EAX_reg(context
) = *(DWORD
*)addr
;
265 else SET_LOWORD(EAX_reg(context
),*(WORD
*)addr
);
268 if (long_op
) ECX_reg(context
) = *(DWORD
*)addr
;
269 else SET_LOWORD(ECX_reg(context
),*(WORD
*)addr
);
272 if (long_op
) EDX_reg(context
) = *(DWORD
*)addr
;
273 else SET_LOWORD(EDX_reg(context
),*(WORD
*)addr
);
276 if (long_op
) EBX_reg(context
) = *(DWORD
*)addr
;
277 else SET_LOWORD(EBX_reg(context
),*(WORD
*)addr
);
280 if (long_op
) ESP_reg(context
) = *(DWORD
*)addr
;
281 else SET_LOWORD(ESP_reg(context
),*(WORD
*)addr
);
284 if (long_op
) EBP_reg(context
) = *(DWORD
*)addr
;
285 else SET_LOWORD(EBP_reg(context
),*(WORD
*)addr
);
288 if (long_op
) ESI_reg(context
) = *(DWORD
*)addr
;
289 else SET_LOWORD(ESI_reg(context
),*(WORD
*)addr
);
292 if (long_op
) EDI_reg(context
) = *(DWORD
*)addr
;
293 else SET_LOWORD(EDI_reg(context
),*(WORD
*)addr
);
297 /* Store the correct segment in the segment register */
301 case 0xc4: ES_reg(context
) = seg
; break; /* les */
302 case 0xc5: DS_reg(context
) = seg
; break; /* lds */
303 case 0x0f: switch(instr
[1])
305 case 0xb2: SS_reg(context
) = seg
; break; /* lss */
306 case 0xb4: FS_reg(context
) = seg
; break; /* lfs */
307 case 0xb5: GS_reg(context
) = seg
; break; /* lgs */
312 /* Add the opcode size to the total length */
314 *len
+= 1 + (*instr
== 0x0f);
318 /***********************************************************************
321 * input on a I/O port
323 static DWORD
INSTR_inport( WORD port
, int size
, CONTEXT86
*context
)
325 DWORD res
= IO_inport( port
, size
);
331 DPRINTF( "0x%x < %02x @ %04x:%04x\n", port
, LOBYTE(res
),
332 (WORD
)CS_reg(context
), LOWORD(EIP_reg(context
)));
335 DPRINTF( "0x%x < %04x @ %04x:%04x\n", port
, LOWORD(res
),
336 (WORD
)CS_reg(context
), LOWORD(EIP_reg(context
)));
339 DPRINTF( "0x%x < %08lx @ %04x:%04x\n", port
, res
,
340 (WORD
)CS_reg(context
), LOWORD(EIP_reg(context
)));
348 /***********************************************************************
351 * output on a I/O port
353 static void INSTR_outport( WORD port
, int size
, DWORD val
, CONTEXT86
*context
)
355 IO_outport( port
, size
, val
);
361 DPRINTF("0x%x > %02x @ %04x:%04x\n", port
, LOBYTE(val
),
362 (WORD
)CS_reg(context
), LOWORD(EIP_reg(context
)));
365 DPRINTF("0x%x > %04x @ %04x:%04x\n", port
, LOWORD(val
),
366 (WORD
)CS_reg(context
), LOWORD(EIP_reg(context
)));
369 DPRINTF("0x%x > %08lx @ %04x:%04x\n", port
, val
,
370 (WORD
)CS_reg(context
), LOWORD(EIP_reg(context
)));
377 /***********************************************************************
378 * INSTR_EmulateInstruction
380 * Emulate a priviledged instruction. Returns TRUE if emulation successful.
382 BOOL
INSTR_EmulateInstruction( CONTEXT86
*context
)
384 int prefix
, segprefix
, prefixlen
, len
, repX
, long_op
, long_addr
;
388 long_op
= long_addr
= IS_SEL_32(context
,CS_reg(context
));
389 instr
= (BYTE
*)MK_PTR(context
,CS_reg(context
),EIP_reg(context
));
390 if (!instr
) return FALSE
;
392 /* First handle any possible prefix */
394 segprefix
= -1; /* no prefix */
403 segprefix
= CS_reg(context
);
406 segprefix
= SS_reg(context
);
409 segprefix
= DS_reg(context
);
412 segprefix
= ES_reg(context
);
415 segprefix
= FS_reg(context
);
418 segprefix
= GS_reg(context
);
421 long_op
= !long_op
; /* opcode size prefix */
424 long_addr
= !long_addr
; /* addr size prefix */
426 case 0xf0: /* lock */
428 case 0xf2: /* repne */
431 case 0xf3: /* repe */
435 prefix
= 0; /* no more prefixes */
445 /* Now look at the actual instruction */
449 case 0x07: /* pop es */
450 case 0x17: /* pop ss */
451 case 0x1f: /* pop ds */
453 WORD seg
= *(WORD
*)STACK_PTR( context
);
454 if (INSTR_ReplaceSelector( context
, &seg
))
458 case 0x07: ES_reg(context
) = seg
; break;
459 case 0x17: SS_reg(context
) = seg
; break;
460 case 0x1f: DS_reg(context
) = seg
; break;
462 ADD_STACK_reg(context
, long_op
? 4 : 2);
463 EIP_reg(context
) += prefixlen
+ 1;
467 break; /* Unable to emulate it */
469 case 0x0f: /* extended instruction */
472 case 0x22: /* mov eax, crX */
475 fprintf(stderr
,"mov eax,cr0 at 0x%08lx, EAX=0x%08lx\n",
476 EIP_reg(context
),EAX_reg(context
)
478 EIP_reg(context
) += prefixlen
+3;
481 break; /*fallthrough to bad instruction handling */
483 break; /*fallthrough to bad instruction handling */
484 case 0x20: /* mov crX, eax */
486 case 0xe0: /* mov cr4, eax */
487 /* CR4 register . See linux/arch/i386/mm/init.c, X86_CR4_ defs
488 * bit 0: VME Virtual Mode Exception ?
489 * bit 1: PVI Protected mode Virtual Interrupt
490 * bit 2: TSD Timestamp disable
491 * bit 3: DE Debugging extensions
492 * bit 4: PSE Page size extensions
493 * bit 5: PAE Physical address extension
494 * bit 6: MCE Machine check enable
495 * bit 7: PGE Enable global pages
496 * bit 8: PCE Enable performance counters at IPL3
498 fprintf(stderr
,"mov cr4,eax at 0x%08lx\n",EIP_reg(context
));
499 EAX_reg(context
) = 0;
500 EIP_reg(context
) += prefixlen
+3;
502 case 0xc0: /* mov cr0, eax */
503 fprintf(stderr
,"mov cr0,eax at 0x%08lx\n",EIP_reg(context
));
504 EAX_reg(context
) = 0x10; /* FIXME: set more bits ? */
505 EIP_reg(context
) += prefixlen
+3;
507 default: /* fallthrough to illegal instruction */
510 /* fallthrough to illegal instruction */
512 case 0xa1: /* pop fs */
514 WORD seg
= *(WORD
*)STACK_PTR( context
);
515 if (INSTR_ReplaceSelector( context
, &seg
))
517 FS_reg(context
) = seg
;
518 ADD_STACK_reg(context
, long_op
? 4 : 2);
519 EIP_reg(context
) += prefixlen
+ 2;
524 case 0xa9: /* pop gs */
526 WORD seg
= *(WORD
*)STACK_PTR( context
);
527 if (INSTR_ReplaceSelector( context
, &seg
))
529 GS_reg(context
) = seg
;
530 ADD_STACK_reg(context
, long_op
? 4 : 2);
531 EIP_reg(context
) += prefixlen
+ 2;
536 case 0xb2: /* lss addr,reg */
537 case 0xb4: /* lfs addr,reg */
538 case 0xb5: /* lgs addr,reg */
539 if (INSTR_EmulateLDS( context
, instr
, long_op
,
540 long_addr
, segprefix
, &len
))
542 EIP_reg(context
) += prefixlen
+ len
;
547 break; /* Unable to emulate it */
549 case 0x6c: /* insb */
550 case 0x6d: /* insw/d */
551 case 0x6e: /* outsb */
552 case 0x6f: /* outsw/d */
554 int typ
= *instr
; /* Just in case it's overwritten. */
555 int outp
= (typ
>= 0x6e);
556 unsigned long count
= repX
?
557 (long_addr
? ECX_reg(context
) : LOWORD(ECX_reg(context
))) : 1;
558 int opsize
= (typ
& 1) ? (long_op
? 4 : 2) : 1;
559 int step
= (EFL_reg(context
) & 0x400) ? -opsize
: +opsize
;
560 int seg
= outp
? DS_reg(context
) : ES_reg(context
); /* FIXME: is this right? */
563 /* FIXME: Check segment readable. */
566 /* FIXME: Check segment writeable. */
571 if (long_addr
) ECX_reg(context
) = 0;
572 else SET_LOWORD(ECX_reg(context
),0);
578 WORD dx
= LOWORD(EDX_reg(context
));
581 data
= MK_PTR(context
, seg
,
582 long_addr
? ESI_reg(context
) : LOWORD(ESI_reg(context
)));
583 if (long_addr
) ESI_reg(context
) += step
;
584 else ADD_LOWORD(ESI_reg(context
),step
);
588 data
= MK_PTR(context
, seg
,
589 long_addr
? EDI_reg(context
) : LOWORD(EDI_reg(context
)));
590 if (long_addr
) EDI_reg(context
) += step
;
591 else ADD_LOWORD(EDI_reg(context
),step
);
597 *(BYTE
*)data
= INSTR_inport( dx
, 1, context
);
601 *(DWORD
*)data
= INSTR_inport( dx
, 4, context
);
603 *(WORD
*)data
= INSTR_inport( dx
, 2, context
);
606 INSTR_outport( dx
, 1, *(BYTE
*)data
, context
);
610 INSTR_outport( dx
, 4, *(DWORD
*)data
, context
);
612 INSTR_outport( dx
, 2, *(WORD
*)data
, context
);
616 EIP_reg(context
) += prefixlen
+ 1;
620 case 0x8e: /* mov XX,segment_reg */
623 BYTE
*addr
= INSTR_GetOperandAddr(context
, instr
+ 1,
624 long_addr
, segprefix
, &len
);
626 break; /* Unable to emulate it */
628 if (!INSTR_ReplaceSelector( context
, &seg
))
629 break; /* Unable to emulate it */
631 switch((instr
[1] >> 3) & 7)
634 ES_reg(context
) = seg
;
635 EIP_reg(context
) += prefixlen
+ len
+ 1;
640 SS_reg(context
) = seg
;
641 EIP_reg(context
) += prefixlen
+ len
+ 1;
644 DS_reg(context
) = seg
;
645 EIP_reg(context
) += prefixlen
+ len
+ 1;
648 FS_reg(context
) = seg
;
649 EIP_reg(context
) += prefixlen
+ len
+ 1;
652 GS_reg(context
) = seg
;
653 EIP_reg(context
) += prefixlen
+ len
+ 1;
660 break; /* Unable to emulate it */
662 case 0xc4: /* les addr,reg */
663 case 0xc5: /* lds addr,reg */
664 if (INSTR_EmulateLDS( context
, instr
, long_op
,
665 long_addr
, segprefix
, &len
))
667 EIP_reg(context
) += prefixlen
+ len
;
670 break; /* Unable to emulate it */
672 case 0xcd: /* int <XX> */
675 ERR_(int)("int xx from 32-bit code is not supported.\n");
676 break; /* Unable to emulate it */
680 FARPROC16 addr
= INT_GetPMHandler( instr
[1] );
681 WORD
*stack
= (WORD
*)STACK_PTR( context
);
682 /* Push the flags and return address on the stack */
683 *(--stack
) = LOWORD(EFL_reg(context
));
684 *(--stack
) = CS_reg(context
);
685 *(--stack
) = LOWORD(EIP_reg(context
)) + prefixlen
+ 2;
686 ADD_STACK_reg(context
, -3 * sizeof(WORD
));
687 /* Jump to the interrupt handler */
688 CS_reg(context
) = HIWORD(addr
);
689 EIP_reg(context
) = LOWORD(addr
);
693 case 0xcf: /* iret */
696 DWORD
*stack
= (DWORD
*)STACK_PTR( context
);
697 EIP_reg(context
) = *stack
++;
698 CS_reg(context
) = *stack
++;
699 EFL_reg(context
) = *stack
;
700 ADD_STACK_reg(context
, 3*sizeof(DWORD
)); /* Pop the return address and flags */
704 WORD
*stack
= (WORD
*)STACK_PTR( context
);
705 EIP_reg(context
) = *stack
++;
706 CS_reg(context
) = *stack
++;
707 SET_LOWORD(EFL_reg(context
),*stack
);
708 ADD_STACK_reg(context
, 3*sizeof(WORD
)); /* Pop the return address and flags */
712 case 0xe4: /* inb al,XX */
713 SET_LOBYTE(EAX_reg(context
),INSTR_inport( instr
[1], 1, context
));
714 EIP_reg(context
) += prefixlen
+ 2;
717 case 0xe5: /* in (e)ax,XX */
719 EAX_reg(context
) = INSTR_inport( instr
[1], 4, context
);
721 SET_LOWORD(EAX_reg(context
), INSTR_inport( instr
[1], 2, context
));
722 EIP_reg(context
) += prefixlen
+ 2;
725 case 0xe6: /* outb XX,al */
726 INSTR_outport( instr
[1], 1, LOBYTE(EAX_reg(context
)), context
);
727 EIP_reg(context
) += prefixlen
+ 2;
730 case 0xe7: /* out XX,(e)ax */
732 INSTR_outport( instr
[1], 4, EAX_reg(context
), context
);
734 INSTR_outport( instr
[1], 2, LOWORD(EAX_reg(context
)), context
);
735 EIP_reg(context
) += prefixlen
+ 2;
738 case 0xec: /* inb al,dx */
739 SET_LOBYTE(EAX_reg(context
), INSTR_inport( LOWORD(EDX_reg(context
)), 1, context
) );
740 EIP_reg(context
) += prefixlen
+ 1;
743 case 0xed: /* in (e)ax,dx */
745 EAX_reg(context
) = INSTR_inport( LOWORD(EDX_reg(context
)), 4, context
);
747 SET_LOWORD(EAX_reg(context
), INSTR_inport( LOWORD(EDX_reg(context
)), 2, context
));
748 EIP_reg(context
) += prefixlen
+ 1;
751 case 0xee: /* outb dx,al */
752 INSTR_outport( LOWORD(EDX_reg(context
)), 1, LOBYTE(EAX_reg(context
)), context
);
753 EIP_reg(context
) += prefixlen
+ 1;
756 case 0xef: /* out dx,(e)ax */
758 INSTR_outport( LOWORD(EDX_reg(context
)), 4, EAX_reg(context
), context
);
760 INSTR_outport( LOWORD(EDX_reg(context
)), 2, LOWORD(EAX_reg(context
)), context
);
761 EIP_reg(context
) += prefixlen
+ 1;
764 case 0xfa: /* cli, ignored */
765 EIP_reg(context
) += prefixlen
+ 1;
768 case 0xfb: /* sti, ignored */
769 EIP_reg(context
) += prefixlen
+ 1;
774 /* Check for Win16 __GP handler */
775 gpHandler
= HasGPHandler16( PTR_SEG_OFF_TO_SEGPTR( CS_reg(context
),
776 EIP_reg(context
) ) );
779 WORD
*stack
= (WORD
*)STACK_PTR( context
);
780 *--stack
= CS_reg(context
);
781 *--stack
= EIP_reg(context
);
782 ADD_STACK_reg(context
, -2*sizeof(WORD
));
784 CS_reg(context
) = SELECTOROF( gpHandler
);
785 EIP_reg(context
) = OFFSETOF( gpHandler
);
788 return FALSE
; /* Unable to emulate it */
791 #endif /* __i386__ */