xen: add irq_from_evtchn

Given an evtchn, return the corresponding irq.

Signed-off-by: Ian Campbell <[email protected]>
Signed-off-by: Jeremy Fitzhardinge <[email protected]>

diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 30963af5dba02960143f9ebf37b6f85d44de0dec..1cd2a0e15ae8e47d25e09b2fce42714700a0ef0a 100644 (file)
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -151,6 +151,12 @@ static unsigned int evtchn_from_irq(unsigned irq)
        return info_for_irq(irq)->evtchn;
 }
 
+unsigned irq_from_evtchn(unsigned int evtchn)
+{
+       return evtchn_to_irq[evtchn];
+}
+EXPORT_SYMBOL_GPL(irq_from_evtchn);
+
 static enum ipi_vector ipi_from_irq(unsigned irq)
 {
        struct irq_info *info = info_for_irq(irq);

diff --git a/include/xen/events.h b/include/xen/events.h
index 0d5f1adc0363e9e125cb8786ca96b0917440b6b5..e68d59a90ca88b73c21b431c3cf538165916d5a7 100644 (file)
--- a/include/xen/events.h
+++ b/include/xen/events.h
@@ -53,4 +53,7 @@ bool xen_test_irq_pending(int irq);
    irq will be disabled so it won't deliver an interrupt. */
 void xen_poll_irq(int irq);
 
+/* Determine the IRQ which is bound to an event channel */
+unsigned irq_from_evtchn(unsigned int evtchn);
+
 #endif /* _XEN_EVENTS_H */