aboutsummaryrefslogtreecommitdiff
path: root/drivers/virtio/virtio_ring.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/virtio/virtio_ring.c')
-rw-r--r--drivers/virtio/virtio_ring.c23
1 files changed, 21 insertions, 2 deletions
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 72bf8bc0901..6eb5303fed1 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -18,6 +18,7 @@
*/
#include <linux/virtio.h>
#include <linux/virtio_ring.h>
+#include <linux/virtio_config.h>
#include <linux/device.h>
#ifdef DEBUG
@@ -87,8 +88,11 @@ static int vring_add_buf(struct virtqueue *_vq,
if (vq->num_free < out + in) {
pr_debug("Can't add buf len %i - avail = %i\n",
out + in, vq->num_free);
- /* We notify *even if* VRING_USED_F_NO_NOTIFY is set here. */
- vq->notify(&vq->vq);
+ /* FIXME: for historical reasons, we force a notify here if
+ * there are outgoing parts to the buffer. Presumably the
+ * host should service the ring ASAP. */
+ if (out)
+ vq->notify(&vq->vq);
END_USE(vq);
return -ENOSPC;
}
@@ -320,4 +324,19 @@ void vring_del_virtqueue(struct virtqueue *vq)
}
EXPORT_SYMBOL_GPL(vring_del_virtqueue);
+/* Manipulates transport-specific feature bits. */
+void vring_transport_features(struct virtio_device *vdev)
+{
+ unsigned int i;
+
+ for (i = VIRTIO_TRANSPORT_F_START; i < VIRTIO_TRANSPORT_F_END; i++) {
+ switch (i) {
+ default:
+ /* We don't understand this bit. */
+ clear_bit(i, vdev->features);
+ }
+ }
+}
+EXPORT_SYMBOL_GPL(vring_transport_features);
+
MODULE_LICENSE("GPL");