vDPA/ifcvf: implement vdpa_config_ops.get_vq_size

This commit implements vdpa_ops.get_vq_size to report
the size of a specific virtqueue.
Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Message-Id: <20240202163905.8834-4-lingshan.zhu@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

drivers/vdpa/ifcvf/ifcvf_base.c

@@ -69,10 +69,13 @@ static int ifcvf_read_config_range(struct pci_dev *dev,
 	return 0;
 }
 
-static u16 ifcvf_get_vq_size(struct ifcvf_hw *hw, u16 qid)
+u16 ifcvf_get_vq_size(struct ifcvf_hw *hw, u16 qid)
 {
 	u16 queue_size;
 
+	if (qid >= hw->nr_vring)
+		return 0;
+
 	vp_iowrite16(qid, &hw->common_cfg->queue_select);
 	queue_size = vp_ioread16(&hw->common_cfg->queue_size);
 

drivers/vdpa/ifcvf/ifcvf_base.h

@@ -131,4 +131,5 @@ void ifcvf_set_vq_ready(struct ifcvf_hw *hw, u16 qid, bool ready);
 void ifcvf_set_driver_features(struct ifcvf_hw *hw, u64 features);
 u64 ifcvf_get_driver_features(struct ifcvf_hw *hw);
 u16 ifcvf_get_max_vq_size(struct ifcvf_hw *hw);
+u16 ifcvf_get_vq_size(struct ifcvf_hw *hw, u16 qid);
 #endif /* _IFCVF_H_ */

drivers/vdpa/ifcvf/ifcvf_main.c

@@ -597,6 +597,14 @@ static int ifcvf_vdpa_get_vq_irq(struct vdpa_device *vdpa_dev,
 		return -EINVAL;
 }
 
+static u16 ifcvf_vdpa_get_vq_size(struct vdpa_device *vdpa_dev,
+			     u16 qid)
+{
+	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
+
+	return ifcvf_get_vq_size(vf, qid);
+}
+
 static struct vdpa_notification_area ifcvf_get_vq_notification(struct vdpa_device *vdpa_dev,
 							       u16 idx)
 {
@@ -632,6 +640,7 @@ static const struct vdpa_config_ops ifc_vdpa_ops = {
 	.set_vq_num	= ifcvf_vdpa_set_vq_num,
 	.set_vq_address	= ifcvf_vdpa_set_vq_address,
 	.get_vq_irq	= ifcvf_vdpa_get_vq_irq,
+	.get_vq_size	= ifcvf_vdpa_get_vq_size,
 	.kick_vq	= ifcvf_vdpa_kick_vq,
 	.get_generation	= ifcvf_vdpa_get_generation,
 	.get_device_id	= ifcvf_vdpa_get_device_id,