Re: [PATCH v1 5/8] virtio-ccw: Handle extra notification data

[Eric Farman]

On Mon, 2024-03-04 at 14:46 -0500, Jonah Palmer wrote:
> > Add support to virtio-ccw devices for handling the extra data sent
> > from
> > the driver to the device when the VIRTIO_F_NOTIFICATION_DATA
> > transport
> > feature has been negotiated.
> > 
> > The extra data that's passed to the virtio-ccw device when this
> > feature
> > is enabled varies depending on the device's virtqueue layout.
> > 
> > That data passed to the virtio-ccw device is in the same format as
> > the
> > data passed to virtio-pci devices.
> > 
> > Acked-by: Thomas Huth 
> > Signed-off-by: Jonah Palmer 
> > ---
> >  hw/s390x/s390-virtio-ccw.c | 16 
> >  1 file changed, 12 insertions(+), 4 deletions(-)

Acked-by: Eric Farman 

(I see a v2 is coming for the ioeventfd side, but I was going through
this series today and thought that would affect the next patch rather
than this one.)

[PATCH v1 5/8] virtio-ccw: Handle extra notification data

[Jonah Palmer]

Add support to virtio-ccw devices for handling the extra data sent from
the driver to the device when the VIRTIO_F_NOTIFICATION_DATA transport
feature has been negotiated.

The extra data that's passed to the virtio-ccw device when this feature
is enabled varies depending on the device's virtqueue layout.

That data passed to the virtio-ccw device is in the same format as the
data passed to virtio-pci devices.

Acked-by: Thomas Huth 
Signed-off-by: Jonah Palmer 
---
 hw/s390x/s390-virtio-ccw.c | 16 
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index 62804cc228..828052046b 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -140,9 +140,11 @@ static void subsystem_reset(void)
 static int virtio_ccw_hcall_notify(const uint64_t *args)
 {
 uint64_t subch_id = args[0];
-uint64_t queue = args[1];
+uint64_t data = args[1];
 SubchDev *sch;
+VirtIODevice *vdev;
 int cssid, ssid, schid, m;
+uint16_t vq_idx = data;
 
 if (ioinst_disassemble_sch_ident(subch_id, , , , )) {
 return -EINVAL;
@@ -151,12 +153,18 @@ static int virtio_ccw_hcall_notify(const uint64_t *args)
 if (!sch || !css_subch_visible(sch)) {
 return -EINVAL;
 }
-if (queue >= VIRTIO_QUEUE_MAX) {
+
+if (vq_idx >= VIRTIO_QUEUE_MAX) {
 return -EINVAL;
 }
-virtio_queue_notify(virtio_ccw_get_vdev(sch), queue);
-return 0;
 
+vdev = virtio_ccw_get_vdev(sch);
+if (virtio_vdev_has_feature(vdev, VIRTIO_F_NOTIFICATION_DATA)) {
+virtio_queue_set_shadow_avail_data(vdev, data);
+}
+
+virtio_queue_notify(vdev, vq_idx);
+return 0;
 }
 
 static int virtio_ccw_hcall_early_printk(const uint64_t *args)
-- 
2.39.3