Index: sys/xen/xen_intr.c
===================================================================
--- sys/xen/xen_intr.c
+++ sys/xen/xen_intr.c
@@ -236,7 +236,7 @@
  * \return  A pointer to a free Xen interrupt source object or NULL.
  */
 static struct xenisrc *
-xen_intr_find_unused_isrc(enum evtchn_type type)
+xen_intr_find_unused_isrc(const struct xenisrc *const params)
 {
 	int isrc_idx;
 
@@ -252,7 +252,9 @@
 		 && isrc->xi_type == EVTCHN_TYPE_UNBOUND) {
 			KASSERT(!xen_arch_intr_has_handlers(isrc),
 			    ("Free evtchn still has handlers"));
-			isrc->xi_type = type;
+			CTASSERT(offsetof(struct xenisrc, xi_arch) == 0);
+			memcpy(&isrc->xi_arch + 1, &params->xi_arch + 1,
+			    sizeof(struct xenisrc) - sizeof(xen_arch_isrc_t));
 			return (isrc);
 		}
 	}
@@ -268,14 +270,14 @@
  *          object or NULL.
  */
 static struct xenisrc *
-xen_intr_alloc_isrc(enum evtchn_type type)
+xen_intr_alloc_isrc(const struct xenisrc *const params)
 {
 	static int warned;
 	struct xenisrc *isrc;
 	unsigned int vector;
 
 	mtx_lock(&xen_intr_x86_lock);
-	isrc = xen_intr_find_unused_isrc(type);
+	isrc = xen_intr_find_unused_isrc(params);
 
 	if (isrc != NULL) {
 		mtx_unlock(&xen_intr_x86_lock);
@@ -301,7 +303,10 @@
 	isrc = malloc(sizeof(*isrc), M_XENINTR, M_WAITOK | M_ZERO);
 	isrc->xi_arch.xai_intsrc.is_pic = &xen_intr_pic;
 	isrc->xi_arch.xai_vector = vector;
-	isrc->xi_type = type;
+
+	CTASSERT(offsetof(struct xenisrc, xi_arch) == 0);
+	memcpy(&isrc->xi_arch + 1, &params->xi_arch + 1,
+	    sizeof(struct xenisrc) - sizeof(xen_arch_isrc_t));
 	if (intr_register_source(&isrc->xi_arch.xai_intsrc) != 0) {
 		free(isrc, M_XENINTR);
 		return (NULL);
@@ -380,8 +385,8 @@
  * \returns  0 on success, otherwise an errno.
  */
 static int
-xen_intr_bind_isrc(struct xenisrc **isrcp, evtchn_port_t local_port,
-    enum evtchn_type type, const char *intr_owner, driver_filter_t filter,
+xen_intr_bind_isrc(struct xenisrc **isrcp, const struct xenisrc *params,
+    const char *intr_owner, driver_filter_t filter,
     driver_intr_t handler, void *arg, enum intr_type flags,
     xen_intr_handle_t *port_handlep)
 {
@@ -394,11 +399,10 @@
 		return (EINVAL);
 	}
 
-	isrc = xen_intr_alloc_isrc(type);
+	isrc = xen_intr_alloc_isrc(params);
 	if (isrc == NULL)
 		return (ENOSPC);
 	mtx_lock(&xen_intr_isrc_lock);
-	isrc->xi_port = local_port;
 	xen_intr_port_to_isrc[isrc->xi_port] = isrc;
 	refcount_init(&isrc->xi_refcount, 1);
 	mtx_unlock(&xen_intr_isrc_lock);
@@ -407,7 +411,7 @@
 	*port_handlep = xen_intr_handle_from_isrc(isrc);
 
 #ifdef SMP
-	if (type == EVTCHN_TYPE_PORT) {
+	if (params->xi_type == EVTCHN_TYPE_PORT) {
 		/*
 		 * By default all interrupts are assigned to vCPU#0
 		 * unless specified otherwise, so shuffle them to balance
@@ -923,20 +927,19 @@
     enum intr_type flags, xen_intr_handle_t *port_handlep)
 {
 	struct xenisrc *isrc;
-	int error;
+	struct xenisrc params = {
+		.xi_type = EVTCHN_TYPE_PORT,
+		.xi_port = local_port,
+		/*
+		 * The Event Channel API didn't open this port, so it is not
+		 * responsible for closing it automatically on unbind.
+		 */
+		.xi_close = 0,
+	};
 
-	error = xen_intr_bind_isrc(&isrc, local_port, EVTCHN_TYPE_PORT,
+	return (xen_intr_bind_isrc(&isrc, &params,
 	    device_get_nameunit(dev), filter, handler, arg, flags,
-	    port_handlep);
-	if (error != 0)
-		return (error);
-
-	/*
-	 * The Event Channel API didn't open this port, so it is not
-	 * responsible for closing it automatically on unbind.
-	 */
-	isrc->xi_close = 0;
-	return (0);
+	    port_handlep));
 }
 
 int
@@ -945,6 +948,7 @@
     enum intr_type flags, xen_intr_handle_t *port_handlep)
 {
 	struct xenisrc *isrc;
+	struct xenisrc params = { .xi_type = EVTCHN_TYPE_PORT, };
 	struct evtchn_alloc_unbound alloc_unbound;
 	int error;
 
@@ -960,11 +964,12 @@
 		return (-error);
 	}
 
-	error = xen_intr_bind_isrc(&isrc, alloc_unbound.port, EVTCHN_TYPE_PORT,
+	params.xi_port = alloc_unbound.port;
+	error = xen_intr_bind_isrc(&isrc, &params,
 	    device_get_nameunit(dev), filter, handler, arg, flags,
 	    port_handlep);
 	if (error != 0) {
-		evtchn_close_t close = { .port = alloc_unbound.port };
+		evtchn_close_t close = { .port = params.xi_port };
 		if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close))
 			panic("EVTCHNOP_close failed");
 		return (error);
@@ -980,6 +985,9 @@
     void *arg, enum intr_type flags, xen_intr_handle_t *port_handlep)
 {
 	struct xenisrc *isrc;
+	struct xenisrc params = {
+		.xi_type = EVTCHN_TYPE_PORT,
+	};
 	struct evtchn_bind_interdomain bind_interdomain;
 	int error;
 
@@ -995,11 +1003,12 @@
 		return (-error);
 	}
 
-	error = xen_intr_bind_isrc(&isrc, bind_interdomain.local_port,
-	    EVTCHN_TYPE_PORT, device_get_nameunit(dev), filter, handler, arg,
+	params.xi_port = bind_interdomain.local_port;
+	error = xen_intr_bind_isrc(&isrc, &params,
+	    device_get_nameunit(dev), filter, handler, arg,
 	    flags, port_handlep);
 	if (error) {
-		evtchn_close_t close = { .port = bind_interdomain.local_port };
+		evtchn_close_t close = { .port = params.xi_port };
 		if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close))
 			panic("EVTCHNOP_close failed");
 		return (error);
@@ -1020,6 +1029,10 @@
 {
 	int vcpu_id = PCPU_ID_GET(cpu);
 	struct xenisrc *isrc;
+	struct xenisrc params = {
+		.xi_type = EVTCHN_TYPE_VIRQ,
+		.xi_virq = virq,
+	};
 	struct evtchn_bind_virq bind_virq = { .virq = virq, .vcpu = vcpu_id };
 	int error;
 
@@ -1033,7 +1046,8 @@
 		return (-error);
 	}
 
-	error = xen_intr_bind_isrc(&isrc, bind_virq.port, EVTCHN_TYPE_VIRQ,
+	params.xi_port = bind_virq.port;
+	error = xen_intr_bind_isrc(&isrc, &params,
 	    device_get_nameunit(dev), filter, handler, arg, flags,
 	    port_handlep);
 
@@ -1043,7 +1057,7 @@
 #endif
 
 	if (error != 0) {
-		evtchn_close_t close = { .port = bind_virq.port };
+		evtchn_close_t close = { .port = params.xi_port };
 
 		xen_intr_unbind(*port_handlep);
 		if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close))
@@ -1068,7 +1082,6 @@
 	 * responsible for closing it automatically on unbind.
 	 */
 	isrc->xi_close = 1;
-	isrc->xi_virq = virq;
 
 	return (0);
 }
@@ -1080,6 +1093,9 @@
 #ifdef SMP
 	int vcpu_id = PCPU_ID_GET(cpu);
 	struct xenisrc *isrc;
+	struct xenisrc params = {
+		.xi_type = EVTCHN_TYPE_IPI,
+	};
 	struct evtchn_bind_ipi bind_ipi = { .vcpu = vcpu_id };
 	/* Same size as the one used by intr_handler->ih_name. */
 	char name[MAXCOMLEN + 1];
@@ -1095,12 +1111,13 @@
 		return (-error);
 	}
 
+	params.xi_port = bind_ipi.port;
 	snprintf(name, sizeof(name), "cpu%u", cpu);
 
-	error = xen_intr_bind_isrc(&isrc, bind_ipi.port, EVTCHN_TYPE_IPI,
+	error = xen_intr_bind_isrc(&isrc, &params,
 	    name, filter, NULL, NULL, flags, port_handlep);
 	if (error != 0) {
-		evtchn_close_t close = { .port = bind_ipi.port };
+		evtchn_close_t close = { .port = params.xi_port };
 
 		xen_intr_unbind(*port_handlep);
 		if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close))