Re: [Qemu-devel] [PATCH 1/4] hw/s390x/virtio-ccw: Add virtio_ccw_device_plugged for virtio-ccw
Date:
Fri, 17 Apr 2015 22:50:43 +0800
On Friday, 17 April 2015, Cornelia Huck <address@hidden> wrote: > On Fri, 17 Apr 2015 20:13:43 +0800 > Shannon Zhao <address@hidden> wrote: > >> Add virtio_ccw_device_plugged, it can be used to get backend's features. >> >> Signed-off-by: Shannon Zhao <address@hidden> >> Signed-off-by: Shannon Zhao <address@hidden> >> --- >> hw/s390x/virtio-ccw.c | 11 +++++++++++ >> 1 file changed, 11 insertions(+) >> >> diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c >> index 130535c..30ca377 100644 >> --- a/hw/s390x/virtio-ccw.c >> +++ b/hw/s390x/virtio-ccw.c >> @@ -1395,6 +1395,16 @@ static int virtio_ccw_load_config(DeviceState *d, QEMUFile *f) >> return 0; >> } >> >> +/* This is called by virtio-bus just after the device is plugged. */ >> +static void virtio_ccw_device_plugged(DeviceState *d) >> +{ >> + VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d); >> + >> + /* Only the first 32 feature bits are used. */ >> + dev->host_features[0] = virtio_bus_get_vdev_features(&dev->bus, >> + dev->host_features[0]); >> +} >> + > > So how does this help? We already fetch the host features in the > realize function. >
please see patch 4/4, in this patch we will move the properties to backends. So the features can't fetch through realize function. If you ask me why we need to move, it's because these properties actually belongs to the backends and then we can support virtio-mmio to have these properties.