virtio: provide a method to get the IRQ affinity mask for a virtqueue
This basically passed up the pci_irq_get_affinity information through
virtio through an optional get_vq_affinity method. It is only implemented
by the PCI backend for now, and only when we use per-virtqueue IRQs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 2ebe506..8355bab 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -58,6 +58,7 @@
* This returns a pointer to the bus name a la pci_name from which
* the caller can then copy.
* @set_vq_affinity: set the affinity for a virtqueue.
+ * @get_vq_affinity: get the affinity for a virtqueue (optional).
*/
typedef void vq_callback_t(struct virtqueue *);
struct virtio_config_ops {
@@ -77,6 +78,8 @@
int (*finalize_features)(struct virtio_device *vdev);
const char *(*bus_name)(struct virtio_device *vdev);
int (*set_vq_affinity)(struct virtqueue *vq, int cpu);
+ const struct cpumask *(*get_vq_affinity)(struct virtio_device *vdev,
+ int index);
};
/* If driver didn't advertise the feature, it will never appear. */