virtio-pci-modern: introduce helper for getting queue nums

This patch introduces helper for getting queue num of modern device.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210104065503.199631-14-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
index 7a89226135aff5ed221853dffb302b98bfeada9a..bccad1329871bd645a780c9b6416c26145e142e2 100644 (file)
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -292,6 +292,17 @@ static u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev,
 
 }
 
+/*
+ * vp_modern_get_num_queues - get the number of virtqueues
+ * @mdev: the modern virtio-pci device
+ *
+ * Returns the number of virtqueues
+ */
+static u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev)
+{
+       return vp_ioread16(&mdev->common->num_queues);
+}
+
 /* virtio config->finalize_features() implementation */
 static int vp_finalize_features(struct virtio_device *vdev)
 {
@@ -510,7 +521,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
        u16 num, off;
        int err;
 
-       if (index >= vp_ioread16(&cfg->num_queues))
+       if (index >= vp_modern_get_num_queues(mdev))
                return ERR_PTR(-ENOENT);
 
        /* Select the queue we're interested in */