iommu: Add iommu_error class event to iommu trace

iommu_error class event can be enabled to trigger when an iommu
error occurs. This trace event is intended to be called to report the
error information. Trace information includes driver name, device name,
iova, and flags.

iommu_error:io_page_fault
Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>

drivers/iommu/iommu-traces.c

@@ -22,3 +22,6 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(detach_device_from_domain);
 /* iommu_map_unmap */
 EXPORT_TRACEPOINT_SYMBOL_GPL(map);
 EXPORT_TRACEPOINT_SYMBOL_GPL(unmap);
+
+/* iommu_error */
+EXPORT_TRACEPOINT_SYMBOL_GPL(io_page_fault);

include/trace/events/iommu.h

@@ -123,6 +123,39 @@ DEFINE_EVENT_PRINT(iommu_map_unmap, unmap,
 			__entry->iova, __entry->size
 	)
 );
+
+DECLARE_EVENT_CLASS(iommu_error,
+
+	TP_PROTO(struct device *dev, unsigned long iova, int flags),
+
+	TP_ARGS(dev, iova, flags),
+
+	TP_STRUCT__entry(
+		__string(device, dev_name(dev))
+		__string(driver, dev_driver_string(dev))
+		__field(u64, iova)
+		__field(int, flags)
+	),
+
+	TP_fast_assign(
+		__assign_str(device, dev_name(dev));
+		__assign_str(driver, dev_driver_string(dev));
+		__entry->iova = iova;
+		__entry->flags = flags;
+	),
+
+	TP_printk("IOMMU:%s %s iova=0x%016llx flags=0x%04x",
+			__get_str(driver), __get_str(device),
+			__entry->iova, __entry->flags
+	)
+);
+
+DEFINE_EVENT(iommu_error, io_page_fault,
+
+	TP_PROTO(struct device *dev, unsigned long iova, int flags),
+
+	TP_ARGS(dev, iova, flags)
+);
 #endif /* _TRACE_IOMMU_H */
 
 /* This part must be outside protection */