xen/events: allow setup of irq_info to fail
The FIFO-based event ABI requires additional setup of newly bound
events (it may need to expand the event array) and this setup may
fail.
xen_irq_info_common_init() is a useful place to put this setup so
allow this call to fail. This call and the other similar calls are
renamed to be *_setup() to reflect that they may now fail.
This failure can only occur with new event channels not on rebind.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index 7c7b744..4f7d94a 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -99,7 +99,7 @@
}
/* Constructors for packed IRQ information. */
-static void xen_irq_info_common_init(struct irq_info *info,
+static int xen_irq_info_common_setup(struct irq_info *info,
unsigned irq,
enum xen_irq_type type,
unsigned short evtchn,
@@ -116,45 +116,47 @@
evtchn_to_irq[evtchn] = irq;
irq_clear_status_flags(irq, IRQ_NOREQUEST|IRQ_NOAUTOEN);
+
+ return 0;
}
-static void xen_irq_info_evtchn_init(unsigned irq,
+static int xen_irq_info_evtchn_setup(unsigned irq,
unsigned short evtchn)
{
struct irq_info *info = info_for_irq(irq);
- xen_irq_info_common_init(info, irq, IRQT_EVTCHN, evtchn, 0);
+ return xen_irq_info_common_setup(info, irq, IRQT_EVTCHN, evtchn, 0);
}
-static void xen_irq_info_ipi_init(unsigned cpu,
+static int xen_irq_info_ipi_setup(unsigned cpu,
unsigned irq,
unsigned short evtchn,
enum ipi_vector ipi)
{
struct irq_info *info = info_for_irq(irq);
- xen_irq_info_common_init(info, irq, IRQT_IPI, evtchn, 0);
-
info->u.ipi = ipi;
per_cpu(ipi_to_irq, cpu)[ipi] = irq;
+
+ return xen_irq_info_common_setup(info, irq, IRQT_IPI, evtchn, 0);
}
-static void xen_irq_info_virq_init(unsigned cpu,
+static int xen_irq_info_virq_setup(unsigned cpu,
unsigned irq,
unsigned short evtchn,
unsigned short virq)
{
struct irq_info *info = info_for_irq(irq);
- xen_irq_info_common_init(info, irq, IRQT_VIRQ, evtchn, 0);
-
info->u.virq = virq;
per_cpu(virq_to_irq, cpu)[virq] = irq;
+
+ return xen_irq_info_common_setup(info, irq, IRQT_VIRQ, evtchn, 0);
}
-static void xen_irq_info_pirq_init(unsigned irq,
+static int xen_irq_info_pirq_setup(unsigned irq,
unsigned short evtchn,
unsigned short pirq,
unsigned short gsi,
@@ -163,12 +165,12 @@
{
struct irq_info *info = info_for_irq(irq);
- xen_irq_info_common_init(info, irq, IRQT_PIRQ, evtchn, 0);
-
info->u.pirq.pirq = pirq;
info->u.pirq.gsi = gsi;
info->u.pirq.domid = domid;
info->u.pirq.flags = flags;
+
+ return xen_irq_info_common_setup(info, irq, IRQT_PIRQ, evtchn, 0);
}
/*
@@ -521,6 +523,47 @@
}
EXPORT_SYMBOL_GPL(xen_irq_from_gsi);
+static void __unbind_from_irq(unsigned int irq)
+{
+ struct evtchn_close close;
+ int evtchn = evtchn_from_irq(irq);
+ struct irq_info *info = irq_get_handler_data(irq);
+
+ if (info->refcnt > 0) {
+ info->refcnt--;
+ if (info->refcnt != 0)
+ return;
+ }
+
+ if (VALID_EVTCHN(evtchn)) {
+ close.port = evtchn;
+ if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
+ BUG();
+
+ switch (type_from_irq(irq)) {
+ case IRQT_VIRQ:
+ per_cpu(virq_to_irq, cpu_from_evtchn(evtchn))
+ [virq_from_irq(irq)] = -1;
+ break;
+ case IRQT_IPI:
+ per_cpu(ipi_to_irq, cpu_from_evtchn(evtchn))
+ [ipi_from_irq(irq)] = -1;
+ break;
+ default:
+ break;
+ }
+
+ /* Closed ports are implicitly re-bound to VCPU0. */
+ bind_evtchn_to_cpu(evtchn, 0);
+
+ evtchn_to_irq[evtchn] = -1;
+ }
+
+ BUG_ON(info_for_irq(irq)->type == IRQT_UNBOUND);
+
+ xen_free_irq(irq);
+}
+
/*
* Do not make any assumptions regarding the relationship between the
* IRQ number returned here and the Xen pirq argument.
@@ -536,6 +579,7 @@
{
int irq = -1;
struct physdev_irq irq_op;
+ int ret;
mutex_lock(&irq_mapping_update_lock);
@@ -563,8 +607,13 @@
goto out;
}
- xen_irq_info_pirq_init(irq, 0, pirq, gsi, DOMID_SELF,
+ ret = xen_irq_info_pirq_setup(irq, 0, pirq, gsi, DOMID_SELF,
shareable ? PIRQ_SHAREABLE : 0);
+ if (ret < 0) {
+ __unbind_from_irq(irq);
+ irq = ret;
+ goto out;
+ }
pirq_query_unmask(irq);
/* We try to use the handler with the appropriate semantic for the
@@ -624,7 +673,9 @@
irq_set_chip_and_handler_name(irq, &xen_pirq_chip, handle_edge_irq,
name);
- xen_irq_info_pirq_init(irq, 0, pirq, 0, domid, 0);
+ ret = xen_irq_info_pirq_setup(irq, 0, pirq, 0, domid, 0);
+ if (ret < 0)
+ goto error_irq;
ret = irq_set_msi_desc(irq, msidesc);
if (ret < 0)
goto error_irq;
@@ -632,8 +683,8 @@
mutex_unlock(&irq_mapping_update_lock);
return irq;
error_irq:
+ __unbind_from_irq(irq);
mutex_unlock(&irq_mapping_update_lock);
- xen_free_irq(irq);
return ret;
}
#endif
@@ -703,9 +754,11 @@
return pirq_from_irq(irq);
}
EXPORT_SYMBOL_GPL(xen_pirq_from_irq);
+
int bind_evtchn_to_irq(unsigned int evtchn)
{
int irq;
+ int ret;
mutex_lock(&irq_mapping_update_lock);
@@ -719,7 +772,12 @@
irq_set_chip_and_handler_name(irq, &xen_dynamic_chip,
handle_edge_irq, "event");
- xen_irq_info_evtchn_init(irq, evtchn);
+ ret = xen_irq_info_evtchn_setup(irq, evtchn);
+ if (ret < 0) {
+ __unbind_from_irq(irq);
+ irq = ret;
+ goto out;
+ }
} else {
struct irq_info *info = info_for_irq(irq);
WARN_ON(info == NULL || info->type != IRQT_EVTCHN);
@@ -736,6 +794,7 @@
{
struct evtchn_bind_ipi bind_ipi;
int evtchn, irq;
+ int ret;
mutex_lock(&irq_mapping_update_lock);
@@ -755,8 +814,12 @@
BUG();
evtchn = bind_ipi.port;
- xen_irq_info_ipi_init(cpu, irq, evtchn, ipi);
-
+ ret = xen_irq_info_ipi_setup(cpu, irq, evtchn, ipi);
+ if (ret < 0) {
+ __unbind_from_irq(irq);
+ irq = ret;
+ goto out;
+ }
bind_evtchn_to_cpu(evtchn, cpu);
} else {
struct irq_info *info = info_for_irq(irq);
@@ -835,7 +898,12 @@
evtchn = ret;
}
- xen_irq_info_virq_init(cpu, irq, evtchn, virq);
+ ret = xen_irq_info_virq_setup(cpu, irq, evtchn, virq);
+ if (ret < 0) {
+ __unbind_from_irq(irq);
+ irq = ret;
+ goto out;
+ }
bind_evtchn_to_cpu(evtchn, cpu);
} else {
@@ -851,50 +919,8 @@
static void unbind_from_irq(unsigned int irq)
{
- struct evtchn_close close;
- int evtchn = evtchn_from_irq(irq);
- struct irq_info *info = irq_get_handler_data(irq);
-
- if (WARN_ON(!info))
- return;
-
mutex_lock(&irq_mapping_update_lock);
-
- if (info->refcnt > 0) {
- info->refcnt--;
- if (info->refcnt != 0)
- goto done;
- }
-
- if (VALID_EVTCHN(evtchn)) {
- close.port = evtchn;
- if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
- BUG();
-
- switch (type_from_irq(irq)) {
- case IRQT_VIRQ:
- per_cpu(virq_to_irq, cpu_from_evtchn(evtchn))
- [virq_from_irq(irq)] = -1;
- break;
- case IRQT_IPI:
- per_cpu(ipi_to_irq, cpu_from_evtchn(evtchn))
- [ipi_from_irq(irq)] = -1;
- break;
- default:
- break;
- }
-
- /* Closed ports are implicitly re-bound to VCPU0. */
- bind_evtchn_to_cpu(evtchn, 0);
-
- evtchn_to_irq[evtchn] = -1;
- }
-
- BUG_ON(info_for_irq(irq)->type == IRQT_UNBOUND);
-
- xen_free_irq(irq);
-
- done:
+ __unbind_from_irq(irq);
mutex_unlock(&irq_mapping_update_lock);
}
@@ -1142,7 +1168,7 @@
so there should be a proper type */
BUG_ON(info->type == IRQT_UNBOUND);
- xen_irq_info_evtchn_init(irq, evtchn);
+ (void)xen_irq_info_evtchn_setup(irq, evtchn);
mutex_unlock(&irq_mapping_update_lock);
@@ -1317,7 +1343,7 @@
evtchn = bind_virq.port;
/* Record the new mapping. */
- xen_irq_info_virq_init(cpu, irq, evtchn, virq);
+ (void)xen_irq_info_virq_setup(cpu, irq, evtchn, virq);
bind_evtchn_to_cpu(evtchn, cpu);
}
}
@@ -1341,7 +1367,7 @@
evtchn = bind_ipi.port;
/* Record the new mapping. */
- xen_irq_info_ipi_init(cpu, irq, evtchn, ipi);
+ (void)xen_irq_info_ipi_setup(cpu, irq, evtchn, ipi);
bind_evtchn_to_cpu(evtchn, cpu);
}
}