int
cpu_fetch_syscall_args(struct thread *td, struct syscall_args *sa)
{
struct proc *p;
struct trapframe *frame;
caddr_t params;
int error, n;
p = td->td_proc;
frame = td->td_frame;
sa->code = frame->fixreg[0];
params = (caddr_t)(frame->fixreg + FIRSTARG);
n = NARGREG;
if (sa->code == SYS_syscall) {
/*
* code is first argument,
* followed by actual args.
*/
sa->code = *(u_int *) params;
params += sizeof(register_t);
n -= 1;
} else if (sa->code == SYS___syscall) {
/*
* Like syscall, but code is a quad,
* so as to maintain quad alignment
* for the rest of the args.
*/
params += sizeof(register_t);
sa->code = *(u_int *) params;
params += sizeof(register_t);
n -= 2;
}
if (p->p_sysent->sv_mask)
sa->code &= p->p_sysent->sv_mask;
if (sa->code >= p->p_sysent->sv_size)
sa->callp = &p->p_sysent->sv_table[0];
else
sa->callp = &p->p_sysent->sv_table[sa->code];
sa->narg = sa->callp->sy_narg;
bcopy(params, sa->args, n * sizeof(register_t));
if (sa->narg > n) {
error = copyin(MOREARGS(frame->fixreg[1]), sa->args + n,
(sa->narg - n) * sizeof(register_t));
} else
error = 0;
if (error == 0) {
td->td_retval[0] = 0;
td->td_retval[1] = frame->fixreg[FIRSTARG + 1];
}
return (error);
}
void
EMULNAME(syscall)(struct trapframe *tf)
{
struct lwp * const l = curlwp;
struct proc * const p = l->l_proc;
const struct sysent *callp;
size_t argsize;
register_t code;
register_t realcode;
register_t *params, rval[2];
register_t args[10];
int error;
int n;
LWP_CACHE_CREDS(l, p);
curcpu()->ci_ev_scalls.ev_count++;
code = tf->tf_fixreg[0];
params = tf->tf_fixreg + FIRSTARG;
n = NARGREG;
realcode = code;
{
switch (code) {
case EMULNAMEU(SYS_syscall):
/*
* code is first argument,
* followed by actual args.
*/
code = *params++;
n -= 1;
break;
#if !defined(COMPAT_LINUX)
case EMULNAMEU(SYS___syscall):
params++;
code = *params++;
n -= 2;
break;
#endif
default:
break;
}
code &= EMULNAMEU(SYS_NSYSENT) - 1;
callp = p->p_emul->e_sysent + code;
realcode = code;
}
argsize = callp->sy_argsize;
if (argsize > n * sizeof(register_t)) {
memcpy(args, params, n * sizeof(register_t));
error = copyin(MOREARGS(tf->tf_fixreg[1]),
args + n,
argsize - n * sizeof(register_t));
if (error)
goto bad;
params = args;
}
error = sy_invoke(callp, l, params, rval, code);
if (__predict_true(error == 0)) {
tf->tf_fixreg[FIRSTARG] = rval[0];
tf->tf_fixreg[FIRSTARG + 1] = rval[1];
tf->tf_cr &= ~0x10000000;
} else {
switch (error) {
case ERESTART:
/*
* Set user's pc back to redo the system call.
*/
tf->tf_srr0 -= 4;
break;
case EJUSTRETURN:
/* nothing to do */
break;
default:
bad:
if (p->p_emul->e_errno)
error = p->p_emul->e_errno[error];
tf->tf_fixreg[FIRSTARG] = error;
tf->tf_cr |= 0x10000000;
break;
}
}
userret(l, tf);
}
