On Thu, Mar 14, 2024 at 1:16 PM Jonah Palmer <jonah.pal...@oracle.com> wrote: > > > > On 3/13/24 11:01 PM, Jason Wang wrote: > > On Wed, Mar 13, 2024 at 7:55 PM Jonah Palmer <jonah.pal...@oracle.com> > > wrote: > >> > >> Add support to virtio-pci 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-pci device when this > >> feature is enabled varies depending on the device's virtqueue > >> layout. > >> > >> In a split virtqueue layout, this data includes: > >> - upper 16 bits: shadow_avail_idx > >> - lower 16 bits: virtqueue index > >> > >> In a packed virtqueue layout, this data includes: > >> - upper 16 bits: 1-bit wrap counter & 15-bit shadow_avail_idx > >> - lower 16 bits: virtqueue index > >> > >> Tested-by: Lei Yang <leiy...@redhat.com> > >> Reviewed-by: Eugenio Pérez <epere...@redhat.com> > >> Signed-off-by: Jonah Palmer <jonah.pal...@oracle.com> > >> --- > >> hw/virtio/virtio-pci.c | 10 +++++++--- > >> hw/virtio/virtio.c | 18 ++++++++++++++++++ > >> include/hw/virtio/virtio.h | 1 + > >> 3 files changed, 26 insertions(+), 3 deletions(-) > >> > >> diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > >> index cb6940fc0e..0f5c3c3b2f 100644 > >> --- a/hw/virtio/virtio-pci.c > >> +++ b/hw/virtio/virtio-pci.c > >> @@ -384,7 +384,7 @@ static void virtio_ioport_write(void *opaque, uint32_t > >> addr, uint32_t val) > >> { > >> VirtIOPCIProxy *proxy = opaque; > >> VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); > >> - uint16_t vector; > >> + uint16_t vector, vq_idx; > >> hwaddr pa; > >> > >> switch (addr) { > >> @@ -408,8 +408,12 @@ static void virtio_ioport_write(void *opaque, > >> uint32_t addr, uint32_t val) > >> vdev->queue_sel = val; > >> break; > >> case VIRTIO_PCI_QUEUE_NOTIFY: > >> - if (val < VIRTIO_QUEUE_MAX) { > >> - virtio_queue_notify(vdev, val); > >> + vq_idx = val; > >> + if (vq_idx < VIRTIO_QUEUE_MAX) { > >> + if (virtio_vdev_has_feature(vdev, > >> VIRTIO_F_NOTIFICATION_DATA)) { > >> + virtio_queue_set_shadow_avail_data(vdev, val); > >> + } > >> + virtio_queue_notify(vdev, vq_idx); > >> } > >> break; > >> case VIRTIO_PCI_STATUS: > >> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > >> index d229755eae..bcb9e09df0 100644 > >> --- a/hw/virtio/virtio.c > >> +++ b/hw/virtio/virtio.c > >> @@ -2255,6 +2255,24 @@ void virtio_queue_set_align(VirtIODevice *vdev, int > >> n, int align) > >> } > >> } > >> > >> +void virtio_queue_set_shadow_avail_data(VirtIODevice *vdev, uint32_t data)
Maybe I didn't explain well, but I think it is better to pass directly idx to a VirtQueue *. That way only the caller needs to check for a valid vq idx, and (my understanding is) the virtio.c interface is migrating to VirtQueue * use anyway. > >> +{ > >> + /* Lower 16 bits is the virtqueue index */ > >> + uint16_t i = data; > >> + VirtQueue *vq = &vdev->vq[i]; > >> + > >> + if (!vq->vring.desc) { > >> + return; > >> + } > >> + > >> + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { > >> + vq->shadow_avail_wrap_counter = (data >> 31) & 0x1; > >> + vq->shadow_avail_idx = (data >> 16) & 0x7FFF; > >> + } else { > >> + vq->shadow_avail_idx = (data >> 16); > > > > Do we need to do a sanity check for this value? > > > > Thanks > > > > It can't hurt, right? What kind of check did you have in mind? > > if (vq->shadow_avail_idx >= vq->vring.num) > I'm a little bit lost too. shadow_avail_idx can take all uint16_t values. Maybe you meant checking for a valid vq index, Jason? Thanks! > Or something else? > > >> + } > >> +} > >> + > >> static void virtio_queue_notify_vq(VirtQueue *vq) > >> { > >> if (vq->vring.desc && vq->handle_output) { > >> diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h > >> index c8f72850bc..53915947a7 100644 > >> --- a/include/hw/virtio/virtio.h > >> +++ b/include/hw/virtio/virtio.h > >> @@ -335,6 +335,7 @@ void virtio_queue_update_rings(VirtIODevice *vdev, int > >> n); > >> void virtio_init_region_cache(VirtIODevice *vdev, int n); > >> void virtio_queue_set_align(VirtIODevice *vdev, int n, int align); > >> void virtio_queue_notify(VirtIODevice *vdev, int n); > >> +void virtio_queue_set_shadow_avail_data(VirtIODevice *vdev, uint32_t > >> data); > >> uint16_t virtio_queue_vector(VirtIODevice *vdev, int n); > >> void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector); > >> int virtio_queue_set_host_notifier_mr(VirtIODevice *vdev, int n, > >> -- > >> 2.39.3 > >> > > >