/* putword - put a word into the data array */
int putword(int n,int w)
{
return (putdword(base+n,w));
}
/*
* Handle a GP fault that occurred while in VM86 mode. Things that are easy
* to handle here are done here (much more efficient than trapping to 32-bit
* handler code and then having it restart VM86 mode).
*/
void
vm86_gpfault(struct proc *p, int type)
{
struct trapframe *tf = p->p_md.md_regs;
union sigval sv;
/*
* we want to fetch some stuff from the current user virtual
* address space for checking. remember that the frame's
* segment selectors are real-mode style selectors.
*/
u_long cs, ip, ss, sp;
u_char tmpbyte;
int trace;
cs = CS(tf) << 4;
ip = IP(tf);
ss = SS(tf) << 4;
sp = SP(tf);
trace = tf->tf_eflags & PSL_T;
/*
* For most of these, we must set all the registers before calling
* macros/functions which might do a vm86_return.
*/
tmpbyte = getbyte(cs, ip);
IP(tf) = ip;
switch (tmpbyte) {
case CLI:
/* simulate handling of IF */
clr_vif(p);
break;
case STI:
/* simulate handling of IF.
* XXX the i386 enables interrupts one instruction later.
* code here is wrong, but much simpler than doing it Right.
*/
set_vif(p);
break;
case INTxx:
/* try fast intxx, or return to 32bit mode to handle it. */
tmpbyte = getbyte(cs, ip);
IP(tf) = ip;
fast_intxx(p, tmpbyte);
break;
case INTO:
if (tf->tf_eflags & PSL_V)
fast_intxx(p, 4);
break;
case PUSHF:
putword(ss, sp, get_vflags_short(p));
SP(tf) = sp;
break;
case IRET:
IP(tf) = getword(ss, sp);
CS(tf) = getword(ss, sp);
case POPF:
set_vflags_short(p, getword(ss, sp));
SP(tf) = sp;
break;
case OPSIZ:
tmpbyte = getbyte(cs, ip);
IP(tf) = ip;
switch (tmpbyte) {
case PUSHF:
putdword(ss, sp, get_vflags(p) & ~PSL_VM);
SP(tf) = sp;
break;
case IRET:
IP(tf) = getdword(ss, sp);
CS(tf) = getdword(ss, sp);
case POPF:
set_vflags(p, getdword(ss, sp) | PSL_VM);
SP(tf) = sp;
break;
default:
IP(tf) -= 2;
goto bad;
}
break;
case LOCK:
default:
IP(tf) -= 1;
goto bad;
}
if (trace && tf->tf_eflags & PSL_VM) {
sv.sival_int = 0;
trapsignal(p, SIGTRAP, T_TRCTRAP, TRAP_TRACE, sv);
}
return;
bad:
vm86_return(p, VM86_UNKNOWN);
return;
}
/* setvalue - set the value of a variable in the variable table */
int setvalue(int n, int v)
{
if (n < 1 || n > vcount)
nerror("variable number out of range: %d",n);
return (putdword(vtable+n+n,v));
}
