int physdev_unmap_pirq(domid_t domid, int pirq)
{
struct domain *d;
int ret;
d = rcu_lock_domain_by_any_id(domid);
if ( d == NULL )
return -ESRCH;
ret = xsm_unmap_domain_pirq(XSM_TARGET, d);
if ( ret )
goto free_domain;
if ( is_hvm_domain(d) )
{
spin_lock(&d->event_lock);
if ( domain_pirq_to_emuirq(d, pirq) != IRQ_UNBOUND )
ret = unmap_domain_pirq_emuirq(d, pirq);
spin_unlock(&d->event_lock);
if ( domid == DOMID_SELF || ret )
goto free_domain;
}
spin_lock(&pcidevs_lock);
spin_lock(&d->event_lock);
ret = unmap_domain_pirq(d, pirq);
spin_unlock(&d->event_lock);
spin_unlock(&pcidevs_lock);
free_domain:
rcu_unlock_domain(d);
return ret;
}
static int physdev_unmap_pirq(struct physdev_unmap_pirq *unmap)
{
struct domain *d;
int ret;
ret = rcu_lock_target_domain_by_id(unmap->domid, &d);
if ( ret )
return ret;
if ( is_hvm_domain(d) )
{
spin_lock(&d->event_lock);
if ( domain_pirq_to_emuirq(d, unmap->pirq) != IRQ_UNBOUND )
ret = unmap_domain_pirq_emuirq(d, unmap->pirq);
spin_unlock(&d->event_lock);
if ( unmap->domid == DOMID_SELF || ret )
goto free_domain;
}
ret = -EPERM;
if ( !IS_PRIV_FOR(current->domain, d) )
goto free_domain;
spin_lock(&pcidevs_lock);
spin_lock(&d->event_lock);
ret = unmap_domain_pirq(d, unmap->pirq);
spin_unlock(&d->event_lock);
spin_unlock(&pcidevs_lock);
free_domain:
rcu_unlock_domain(d);
return ret;
}
static long __evtchn_close(struct domain *d1, int port1)
{
struct domain *d2 = NULL;
struct vcpu *v;
struct evtchn *chn1, *chn2;
int port2;
long rc = 0;
again:
spin_lock(&d1->event_lock);
if ( !port_is_valid(d1, port1) )
{
rc = -EINVAL;
goto out;
}
chn1 = evtchn_from_port(d1, port1);
/* Guest cannot close a Xen-attached event channel. */
if ( unlikely(consumer_is_xen(chn1)) )
{
rc = -EINVAL;
goto out;
}
switch ( chn1->state )
{
case ECS_FREE:
case ECS_RESERVED:
rc = -EINVAL;
goto out;
case ECS_UNBOUND:
break;
case ECS_PIRQ: {
struct pirq *pirq = pirq_info(d1, chn1->u.pirq.irq);
if ( !pirq )
break;
if ( !is_hvm_domain(d1) )
pirq_guest_unbind(d1, pirq);
pirq->evtchn = 0;
pirq_cleanup_check(pirq, d1);
unlink_pirq_port(chn1, d1->vcpu[chn1->notify_vcpu_id]);
#ifdef CONFIG_X86
if ( is_hvm_domain(d1) && domain_pirq_to_irq(d1, pirq->pirq) > 0 )
unmap_domain_pirq_emuirq(d1, pirq->pirq);
#endif
break;
}
case ECS_VIRQ:
for_each_vcpu ( d1, v )
{
if ( v->virq_to_evtchn[chn1->u.virq] != port1 )
continue;
v->virq_to_evtchn[chn1->u.virq] = 0;
spin_barrier(&v->virq_lock);
}
break;
case ECS_IPI:
break;
case ECS_INTERDOMAIN:
if ( d2 == NULL )
{
d2 = chn1->u.interdomain.remote_dom;
/* If we unlock d1 then we could lose d2. Must get a reference. */
if ( unlikely(!get_domain(d2)) )
BUG();
if ( d1 < d2 )
{
spin_lock(&d2->event_lock);
}
else if ( d1 != d2 )
{
spin_unlock(&d1->event_lock);
spin_lock(&d2->event_lock);
goto again;
}
}
else if ( d2 != chn1->u.interdomain.remote_dom )
{
/*
* We can only get here if the port was closed and re-bound after
* unlocking d1 but before locking d2 above. We could retry but
* it is easier to return the same error as if we had seen the
* port in ECS_CLOSED. It must have passed through that state for
* us to end up here, so it's a valid error to return.
*/
rc = -EINVAL;
goto out;
}
port2 = chn1->u.interdomain.remote_port;
BUG_ON(!port_is_valid(d2, port2));
chn2 = evtchn_from_port(d2, port2);
BUG_ON(chn2->state != ECS_INTERDOMAIN);
BUG_ON(chn2->u.interdomain.remote_dom != d1);
chn2->state = ECS_UNBOUND;
chn2->u.unbound.remote_domid = d1->domain_id;
break;
default:
BUG();
}
/* Clear pending event to avoid unexpected behavior on re-bind. */
clear_bit(port1, &shared_info(d1, evtchn_pending));
/* Reset binding to vcpu0 when the channel is freed. */
chn1->state = ECS_FREE;
chn1->notify_vcpu_id = 0;
xsm_evtchn_close_post(chn1);
out:
if ( d2 != NULL )
{
if ( d1 != d2 )
spin_unlock(&d2->event_lock);
put_domain(d2);
}
spin_unlock(&d1->event_lock);
return rc;
}
