pc, pc64, xen: change return type of intrdisable() to void

intrdisable() will always be able to unregister the interrupt
now, so there is no reason to have it return an error value.

all drivers except uart8250 already assumed it to never fail
and theres no need to maintain that complexity.

2 files changed, 14 insertions, 23 deletions

diff --git a/sys/src/9/xen/fns.h b/sys/src/9/xen/fns.h
index 71e64ac4c..5b39cfddb 100644
--- a/sys/src/9/xen/fns.h
+++ b/sys/src/9/xen/fns.h
@@ -54,7 +54,7 @@ ushort	ins(int);
 void	inss(int, void*, int);
 ulong	inl(int);
 void	insl(int, void*, int);
-int	intrdisable(int, void (*)(Ureg *, void *), void*, int, char*);
+void	intrdisable(int, void (*)(Ureg *, void *), void*, int, char*);
 void	intrenable(int, void (*)(Ureg*, void*), void*, int, char*);
 int	ioalloc(int, int, int, char*);
 void	ioinit(void);
diff --git a/sys/src/9/xen/trap.c b/sys/src/9/xen/trap.c
index 9d572577b..a81182a8b 100644
--- a/sys/src/9/xen/trap.c
+++ b/sys/src/9/xen/trap.c
@@ -90,36 +90,27 @@ intrenable(int irq, void (*f)(Ureg*, void*), void* a, int tbdf, char *name)
 	iunlock(&vctllock);
 }
 
-int
+void
 intrdisable(int irq, void (*f)(Ureg *, void *), void *a, int tbdf, char *name)
 {
 	Vctl **pv, *v;
 	int vno;
 
-	/*
-	 * For now, none of this will work with the APIC code,
-	 * there is no mapping between irq and vector as the IRQ
-	 * is pretty meaningless.
-	 */
-	if(arch->intrvecno == nil)
-		return -1;
 	vno = arch->intrvecno(irq);
 	ilock(&vctllock);
-	pv = &vctl[vno];
-	while (*pv && 
-		  ((*pv)->irq != irq || (*pv)->tbdf != tbdf || (*pv)->f != f || (*pv)->a != a ||
-		   strcmp((*pv)->name, name)))
-		pv = &((*pv)->next);
-	assert(*pv);
-
-	v = *pv;
-	*pv = (*pv)->next;	/* Link out the entry */
-	
-	if(vctl[vno] == nil && arch->intrdisable != nil)
-		arch->intrdisable(irq);
+	for(pv = &vctl[vno]; (v = *pv) != nil; pv = &v->next){
+		if(v->isintr && v->irq == irq
+		&& v->tbdf == tbdf && v->f == f && v->a == a
+		&& strcmp(v->name, name) == 0){
+			*pv = v->next;
+			xfree(v);
+
+			if(vctl[vno] == nil && arch->intrdisable != nil)
+				arch->intrdisable(irq);
+			break;
+		}
+	}
 	iunlock(&vctllock);
-	xfree(v);
-	return 0;
 }
 
 static long