On 2020/7/22 下午6:08, Zhu Lingshan wrote:

+/*
+ * Request irq for a vq, setup irq offloading if its a vhost_vdpa vq.
+ * This function should be only called through setting virtio DRIVER_OK.
+ * If you want to request irq during probe, you should use raw APIs
+ * like request_irq() or devm_request_irq().

This makes the API less flexibile. The reason is we store the irq in 
vhost-vdpa not vDPA.

I wonder whether the following looks better:

1) store irq in vdpa device
2) register producer when DRIVER_OK and unregister producer when 
!DRIVER_OK in vhost-vDPA
3) deal with the synchronization with SET_VRING_CALL
4) document that irq is not expected to be changed during DRIVER_OK

This can make sure the API works during driver probe, and we don't need 
the setup_irq and unsetup_irq method in vdpa_driver

Thanks

+ */
+int vdpa_devm_request_irq(struct device *dev, struct vdpa_device *vdev,
+			  unsigned int irq, irq_handler_t handler,
+			  unsigned long irqflags, const char *devname, void *dev_id,
+			  int qid)
+{
+	int ret;
+
+	ret = devm_request_irq(dev, irq, handler, irqflags, devname, dev_id);
+	if (ret)
+		dev_err(dev, "Failed to request irq for vq %d\n", qid);
+	else
+		vdpa_setup_irq(vdev, qid, irq);
+
+	return ret;
+
+}
+EXPORT_SYMBOL_GPL(vdpa_devm_request_irq);