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/* $XFree86: xc/programs/Xserver/hw/xfree86/os-support/linux/int10/vm86/linux_vm86.c,v 1.3 2003/11/03 05:36:33 tsi Exp $ */
#include "xf86.h"
#include "xf86_OSproc.h"
#include "xf86_ansic.h"
#include "xf86Pci.h"
#include "compiler.h"
#define _INT10_PRIVATE
#include "xf86int10.h"
#define REG pInt
#ifdef _VM86_LINUX
#include "int10Defines.h"
static int vm86_rep(struct vm86_struct *ptr);
static struct vm86_struct vm86_s;
Bool
xf86Int10ExecSetup(xf86Int10InfoPtr pInt)
{
#define VM86S ((struct vm86_struct *)pInt->cpuRegs)
pInt->cpuRegs = &vm86_s;
VM86S->flags = 0;
VM86S->screen_bitmap = 0;
VM86S->cpu_type = CPU_586;
memset(&VM86S->int_revectored, 0xff, sizeof(VM86S->int_revectored));
memset(&VM86S->int21_revectored, 0xff, sizeof(VM86S->int21_revectored));
return TRUE;
}
/* get the linear address */
#define LIN_PREF_SI ((pref_seg << 4) + X86_SI)
#define LWECX ((prefix66 ^ prefix67) ? X86_ECX : X86_CX)
#define LWECX_ZERO {if (prefix66 ^ prefix67) X86_ECX = 0; else X86_CX = 0;}
#define DF (1 << 10)
/* vm86 fault handling */
static Bool
vm86_GP_fault(xf86Int10InfoPtr pInt)
{
unsigned char *csp, *lina;
CARD32 org_eip;
int pref_seg;
int done, is_rep, prefix66, prefix67;
csp = lina = SEG_ADR((unsigned char *), X86_CS, IP);
is_rep = 0;
prefix66 = prefix67 = 0;
pref_seg = -1;
/* eat up prefixes */
done = 0;
do {
switch (MEM_RB(pInt, (int)csp++)) {
case 0x66: /* operand prefix */ prefix66=1; break;
case 0x67: /* address prefix */ prefix67=1; break;
case 0x2e: /* CS */ pref_seg=X86_CS; break;
case 0x3e: /* DS */ pref_seg=X86_DS; break;
case 0x26: /* ES */ pref_seg=X86_ES; break;
case 0x36: /* SS */ pref_seg=X86_SS; break;
case 0x65: /* GS */ pref_seg=X86_GS; break;
case 0x64: /* FS */ pref_seg=X86_FS; break;
case 0xf0: /* lock */ break;
case 0xf2: /* repnz */
case 0xf3: /* rep */ is_rep=1; break;
default: done=1;
}
} while (!done);
csp--; /* oops one too many */
org_eip = X86_EIP;
X86_IP += (csp - lina);
switch (MEM_RB(pInt, (int)csp)) {
case 0x6c: /* insb */
/* NOTE: ES can't be overwritten; prefixes 66,67 should use esi,edi,ecx
* but is anyone using extended regs in real mode? */
/* WARNING: no test for DI wrapping! */
X86_EDI += port_rep_inb(pInt, X86_DX, SEG_EADR((CARD32), X86_ES, DI),
X86_FLAGS & DF, is_rep ? LWECX : 1);
if (is_rep) LWECX_ZERO;
X86_IP++;
break;
case 0x6d: /* (rep) insw / insd */
/* NOTE: ES can't be overwritten */
/* WARNING: no test for _DI wrapping! */
if (prefix66) {
X86_DI += port_rep_inl(pInt, X86_DX, SEG_ADR((CARD32), X86_ES, DI),
X86_EFLAGS & DF, is_rep ? LWECX : 1);
}
else {
X86_DI += port_rep_inw(pInt, X86_DX, SEG_ADR((CARD32), X86_ES, DI),
X86_FLAGS & DF, is_rep ? LWECX : 1);
}
if (is_rep) LWECX_ZERO;
X86_IP++;
break;
case 0x6e: /* (rep) outsb */
if (pref_seg < 0) pref_seg = X86_DS;
/* WARNING: no test for _SI wrapping! */
X86_SI += port_rep_outb(pInt, X86_DX, (CARD32)LIN_PREF_SI,
X86_FLAGS & DF, is_rep ? LWECX : 1);
if (is_rep) LWECX_ZERO;
X86_IP++;
break;
case 0x6f: /* (rep) outsw / outsd */
if (pref_seg < 0) pref_seg = X86_DS;
/* WARNING: no test for _SI wrapping! */
if (prefix66) {
X86_SI += port_rep_outl(pInt, X86_DX, (CARD32)LIN_PREF_SI,
X86_EFLAGS & DF, is_rep ? LWECX : 1);
}
else {
X86_SI += port_rep_outw(pInt, X86_DX, (CARD32)LIN_PREF_SI,
X86_FLAGS & DF, is_rep ? LWECX : 1);
}
if (is_rep) LWECX_ZERO;
X86_IP++;
break;
case 0xe5: /* inw xx, inl xx */
if (prefix66) X86_EAX = x_inl(csp[1]);
else X86_AX = x_inw(csp[1]);
X86_IP += 2;
break;
case 0xe4: /* inb xx */
X86_AL = x_inb(csp[1]);
X86_IP += 2;
break;
case 0xed: /* inw dx, inl dx */
if (prefix66) X86_EAX = x_inl(X86_DX);
else X86_AX = x_inw(X86_DX);
X86_IP += 1;
break;
case 0xec: /* inb dx */
X86_AL = x_inb(X86_DX);
X86_IP += 1;
break;
case 0xe7: /* outw xx */
if (prefix66) x_outl(csp[1], X86_EAX);
else x_outw(csp[1], X86_AX);
X86_IP += 2;
break;
case 0xe6: /* outb xx */
x_outb(csp[1], X86_AL);
X86_IP += 2;
break;
case 0xef: /* outw dx */
if (prefix66) x_outl(X86_DX, X86_EAX);
else x_outw(X86_DX, X86_AX);
X86_IP += 1;
break;
case 0xee: /* outb dx */
x_outb(X86_DX, X86_AL);
X86_IP += 1;
break;
case 0xf4:
#ifdef DEBUG
ErrorF("hlt at %p\n", lina);
#endif
return FALSE;
case 0x0f:
xf86DrvMsg(pInt->scrnIndex, X_ERROR,
"CPU 0x0f Trap at CS:EIP=0x%4.4x:0x%8.8lx\n", X86_CS, X86_EIP);
goto op0ferr;
default:
xf86DrvMsg(pInt->scrnIndex, X_ERROR, "unknown reason for exception\n");
op0ferr:
dump_registers(pInt);
stack_trace(pInt);
dump_code(pInt);
xf86DrvMsg(pInt->scrnIndex, X_ERROR, "cannot continue\n");
return FALSE;
} /* end of switch() */
return TRUE;
}
static int
do_vm86(xf86Int10InfoPtr pInt)
{
int retval, signo;
xf86InterceptSignals(&signo);
retval = vm86_rep(VM86S);
xf86InterceptSignals(NULL);
if (signo >= 0) {
xf86DrvMsg(pInt->scrnIndex, X_ERROR,
"vm86() syscall generated signal %d.\n", signo);
dump_registers(pInt);
dump_code(pInt);
stack_trace(pInt);
return 0;
}
switch (VM86_TYPE(retval)) {
case VM86_UNKNOWN:
if (!vm86_GP_fault(pInt)) return 0;
break;
case VM86_STI:
xf86DrvMsg(pInt->scrnIndex, X_ERROR, "vm86_sti :-((\n");
dump_registers(pInt);
dump_code(pInt);
stack_trace(pInt);
return 0;
case VM86_INTx:
pInt->num = VM86_ARG(retval);
if (!int_handler(pInt)) {
xf86DrvMsg(pInt->scrnIndex, X_ERROR,
"Unknown vm86_int: 0x%X\n\n", VM86_ARG(retval));
dump_registers(pInt);
dump_code(pInt);
stack_trace(pInt);
return 0;
}
/* I'm not sure yet what to do if we can handle ints */
break;
case VM86_SIGNAL:
return 1;
/*
* we used to warn here and bail out - but now the sigio stuff
* always fires signals at us. So we just ignore them for now.
*/
xf86DrvMsg(pInt->scrnIndex, X_WARNING, "received signal\n");
return 0;
default:
xf86DrvMsg(pInt->scrnIndex, X_ERROR, "unknown type(0x%x)=0x%x\n",
VM86_ARG(retval), VM86_TYPE(retval));
dump_registers(pInt);
dump_code(pInt);
stack_trace(pInt);
return 0;
}
return 1;
}
void
xf86ExecX86int10(xf86Int10InfoPtr pInt)
{
int sig = setup_int(pInt);
if (int_handler(pInt))
while(do_vm86(pInt)) {};
finish_int(pInt, sig);
}
static int
vm86_rep(struct vm86_struct *ptr)
{
int __res;
#ifdef __PIC__
/* When compiling with -fPIC, we can't use asm constraint "b" because
%ebx is already taken by gcc. */
__asm__ __volatile__("pushl %%ebx\n\t"
"movl %2,%%ebx\n\t"
"movl %1,%%eax\n\t"
"int $0x80\n\t"
"popl %%ebx"
:"=a" (__res)
:"n" ((int)113), "r" ((struct vm86_struct *)ptr));
#else
__asm__ __volatile__("int $0x80\n\t"
:"=a" (__res):"a" ((int)113),
"b" ((struct vm86_struct *)ptr));
#endif
if (__res < 0) {
errno = -__res;
__res = -1;
}
else errno = 0;
return __res;
}
#endif
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