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#include <stdarg.h>
#include <string.h>
#include <x86emu.h>
#include "v86.h"
#include "v86_x86emu.h"
u32 stack;
u32 halt;
__BUILDIO(b,b,u8);
__BUILDIO(w,w,u16);
__BUILDIO(l,,u32);
void printk(const char *fmt, ...)
{
va_list argptr;
va_start(argptr, fmt);
vsyslog(LOG_INFO, fmt, argptr);
va_end(argptr);
}
void pushw(u16 val)
{
X86_ESP -= 2;
v_wrw(((u32) X86_SS << 4) + X86_SP, val);
}
static void x86emu_do_int(int num)
{
u32 eflags;
eflags = X86_EFLAGS;
/* Return address and flags */
pushw(eflags);
pushw(X86_CS);
pushw(X86_IP);
X86_EFLAGS = X86_EFLAGS & ~(X86_VIF_MASK | X86_TF_MASK);
X86_CS = v_rdw((num << 2) + 2);
X86_IP = v_rdw((num << 2));
}
int v86_init()
{
X86EMU_intrFuncs intFuncs[256];
X86EMU_pioFuncs pioFuncs = {
.inb = &x_inb,
.inw = &x_inw,
.inl = &x_inl,
.outb = &x_outb,
.outw = &x_outw,
.outl = &x_outl,
};
X86EMU_memFuncs memFuncs = {
.rdb = &v_rdb,
.rdw = &v_rdw,
.rdl = &v_rdl,
.wrb = &v_wrb,
.wrw = &v_wrw,
.wrl = &v_wrl,
};
int i;
if (v86_mem_init()) {
ulog(LOG_ERR, "v86 memory initialization failed.");
return -1;
}
stack = v86_mem_alloc(DEFAULT_STACK_SIZE);
if (!stack) {
ulog(LOG_ERR, "v86 memory allocation failed.");
return -1;
}
X86_SS = stack >> 4;
X86_ESP = DEFAULT_STACK_SIZE;
halt = v86_mem_alloc(0x100);
if (!halt) {
ulog(LOG_ERR, "v86 memory alocation failed.");
return -1;
}
v_wrb(halt, 0xF4);
X86EMU_setupPioFuncs(&pioFuncs);
X86EMU_setupMemFuncs(&memFuncs);
/* Setup interrupt handlers */
for (i = 0; i < 256; i++) {
intFuncs[i] = x86emu_do_int;
}
X86EMU_setupIntrFuncs(intFuncs);
/* Set the default flags */
X86_EFLAGS = X86_IF_MASK | X86_IOPL_MASK;
ioperm(0, 1024, 1);
iopl(3);
return 0;
}
void v86_cleanup()
{
v86_mem_cleanup();
}
void rconv_v86_to_x86emu(struct v86_regs *rs)
{
X86_EAX = rs->eax;
X86_EBX = rs->ebx;
X86_ECX = rs->ecx;
X86_EDX = rs->edx;
X86_EDI = rs->edi;
X86_ESI = rs->esi;
X86_EBP = rs->ebp;
X86_ESP = rs->esp;
X86_EFLAGS = rs->eflags;
X86_EIP = rs->eip;
X86_CS = rs->cs;
X86_DS = rs->ds;
X86_ES = rs->es;
X86_FS = rs->fs;
X86_GS = rs->gs;
}
void rconv_x86emu_to_v86(struct v86_regs *rd)
{
rd->eax = X86_EAX;
rd->ebx = X86_EBX;
rd->ecx = X86_ECX;
rd->edx = X86_EDX;
rd->edi = X86_EDI;
rd->esi = X86_ESI;
rd->ebp = X86_EBP;
rd->esp = X86_ESP;
rd->eflags = X86_EFLAGS;
rd->eip = X86_EIP;
rd->cs = X86_CS;
rd->ds = X86_DS;
rd->es = X86_ES;
rd->fs = X86_FS;
rd->gs = X86_GS;
}
/*
* Perform a simulated interrupt call.
*/
int v86_int(int num, struct v86_regs *regs)
{
rconv_v86_to_x86emu(regs);
X86_GS = 0;
X86_FS = 0;
X86_DS = 0x0040;
X86_CS = v_rdw((num << 2) + 2);
X86_EIP = v_rdw((num << 2));
X86_SS = stack >> 4;
X86_ESP = DEFAULT_STACK_SIZE;
X86_EFLAGS = X86_IF_MASK | X86_IOPL_MASK;
pushw(X86_EFLAGS);
pushw((halt >> 4));
pushw(0x0);
X86EMU_exec();
rconv_x86emu_to_v86(regs);
return 0;
}
void v86_dump_regs()
{
ulog(LOG_DEBUG,
"EAX=0x%8.8lx, EBX=0x%8.8lx, ECX=0x%8.8lx, EDX=0x%8.8lx\n",
(unsigned long)X86_EAX, (unsigned long)X86_EBX,
(unsigned long)X86_ECX, (unsigned long)X86_EDX);
ulog(LOG_DEBUG,
"ESP=0x%8.8lx, EBP=0x%8.8lx, ESI=0x%8.8lx, EDI=0x%8.8lx\n",
(unsigned long)X86_ESP, (unsigned long)X86_EBP,
(unsigned long)X86_ESI, (unsigned long)X86_EDI);
ulog(LOG_DEBUG,
"CS=0x%4.4x, SS=0x%4.4x,"
" DS=0x%4.4x, ES=0x%4.4x, FS=0x%4.4x, GS=0x%4.4x\n",
X86_CS, X86_SS, X86_DS, X86_ES, X86_FS, X86_GS);
ulog(LOG_DEBUG,
"EIP=0x%8.8lx, EFLAGS=0x%8.8lx\n",
(unsigned long)X86_EIP, (unsigned long)X86_EFLAGS);
}
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