[RFC,for,8.0,12/13] vhost: expose vhost_svq_add_element

Commit Message

Eugenio Perez Martin Dec. 5, 2022, 5:04 p.m. UTC

Needed to inject new inflight elements

Signed-off-by: Eugenio Pérez <[e-mail]>
---
 hw/virtio/vhost-shadow-virtqueue.h |  1 +
 hw/virtio/vhost-shadow-virtqueue.c | 12 +++++++++---
 2 files changed, 10 insertions(+), 3 deletions(-)

Patch

diff --git a/hw/virtio/vhost-shadow-virtqueue.h b/hw/virtio/vhost-shadow-virtqueue.h
index e82da4b55c..69910597dd 100644
--- a/hw/virtio/vhost-shadow-virtqueue.h
+++ b/hw/virtio/vhost-shadow-virtqueue.h
@@ -122,6 +122,7 @@  void vhost_svq_push_elem(VhostShadowVirtqueue *svq,
 int vhost_svq_add(VhostShadowVirtqueue *svq, const struct iovec *out_sg,
                   size_t out_num, const struct iovec *in_sg, size_t in_num,
                   VirtQueueElement *elem);
+int vhost_svq_add_element(VhostShadowVirtqueue *svq, VirtQueueElement *elem);
 size_t vhost_svq_poll(VhostShadowVirtqueue *svq);
 
 void vhost_svq_set_svq_kick_fd(VhostShadowVirtqueue *svq, int svq_kick_fd);
diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c
index 029ccee957..0668114897 100644
--- a/hw/virtio/vhost-shadow-virtqueue.c
+++ b/hw/virtio/vhost-shadow-virtqueue.c
@@ -271,9 +271,15 @@  int vhost_svq_add(VhostShadowVirtqueue *svq, const struct iovec *out_sg,
     return 0;
 }
 
-/* Convenience wrapper to add a guest's element to SVQ */
-static int vhost_svq_add_element(VhostShadowVirtqueue *svq,
-                                 VirtQueueElement *elem)
+/*
+ * Add a guest's element to SVQ. SVQ return the element When the device mark
+ * the descriptor as used, so make sure the guest will understand it.
+ *
+ * This function can be used to add the elements after a migration event or in
+ * the case the device is reset. To add elements that must not be seen by the
+ * guest use vhost_svq_add.
+ */
+int vhost_svq_add_element(VhostShadowVirtqueue *svq, VirtQueueElement *elem)
 {
     return vhost_svq_add(svq, elem->out_sg, elem->out_num, elem->in_sg,
                          elem->in_num, elem);