xen/events: add a evtchn_op for port setup

Add a hook for port-specific setup and call it from
xen_irq_info_common_setup().

The FIFO-based ABIs may need to perform additional setup (expanding
the event array) before a bound event channel can start to receive
events.

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 4f7d94abe82cba91160e2719555143a865c98787..929eccb7727073ce5ca70e2fd902f25a697b3721 100644 (file)
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -117,7 +117,7 @@ static int xen_irq_info_common_setup(struct irq_info *info,
 
        irq_clear_status_flags(irq, IRQ_NOREQUEST|IRQ_NOAUTOEN);
 
-       return 0;
+       return xen_evtchn_port_setup(info);
 }
 
 static int xen_irq_info_evtchn_setup(unsigned irq,

diff --git a/drivers/xen/events/events_internal.h b/drivers/xen/events/events_internal.h
index ba8142f0c635388e9cb91de780c72732734b61eb..dc9650265e0412cf4088a9429dbd7891fd8c74c0 100644 (file)
--- a/drivers/xen/events/events_internal.h
+++ b/drivers/xen/events/events_internal.h
@@ -55,6 +55,7 @@ struct irq_info {
 #define PIRQ_SHAREABLE (1 << 1)
 
 struct evtchn_ops {
+       int (*setup)(struct irq_info *info);
        void (*bind_to_cpu)(struct irq_info *info, unsigned cpu);
 
        void (*clear_pending)(unsigned port);
@@ -75,6 +76,17 @@ struct irq_info *info_for_irq(unsigned irq);
 unsigned cpu_from_irq(unsigned irq);
 unsigned cpu_from_evtchn(unsigned int evtchn);
 
+/*
+ * Do any ABI specific setup for a bound event channel before it can
+ * be unmasked and used.
+ */
+static inline int xen_evtchn_port_setup(struct irq_info *info)
+{
+       if (evtchn_ops->setup)
+               return evtchn_ops->setup(info);
+       return 0;
+}
+
 static inline void xen_evtchn_port_bind_to_cpu(struct irq_info *info,
                                               unsigned cpu)
 {