-----Original Message-----
From: Stefano Garzarella [mailto:sgarzare@redhat.com]
Sent: Wednesday, January 19, 2022 7:31 PM
To: Longpeng (Mike, Cloud Infrastructure Service Product Dept.)
<longpeng2@huawei.com>
Cc: stefanha@redhat.com; mst@redhat.com; cohuck@redhat.com;
pbonzini@redhat.com; Gonglei (Arei) <arei.gonglei@huawei.com>; Yechuan
<yechuan@huawei.com>; Huangzhichao <huangzhichao@huawei.com>;
qemu-devel@nongnu.org
Subject: Re: [PATCH v2 05/10] vdpa-dev: implement the realize interface
On Mon, Jan 17, 2022 at 08:43:26PM +0800, Longpeng(Mike) via wrote:
>From: Longpeng <longpeng2@huawei.com>
>
>Implements the .realize interface.
>
>Signed-off-by: Longpeng <longpeng2@huawei.com>
>---
> hw/virtio/vdpa-dev.c | 101 +++++++++++++++++++++++++++++++++++
> include/hw/virtio/vdpa-dev.h | 8 +++
> 2 files changed, 109 insertions(+)
>
>diff --git a/hw/virtio/vdpa-dev.c b/hw/virtio/vdpa-dev.c
>index b103768f33..bd28cf7a15 100644
>--- a/hw/virtio/vdpa-dev.c
>+++ b/hw/virtio/vdpa-dev.c
>@@ -27,9 +27,109 @@ uint32_t vhost_vdpa_device_get_u32(int fd, unsigned long
int cmd, Error **errp)
> return val;
> }
>
>+static void
>+vhost_vdpa_device_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq)
>+{
>+ /* Nothing to do */
>+}
>+
> static void vhost_vdpa_device_realize(DeviceState *dev, Error **errp)
> {
>+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
>+ VhostVdpaDevice *s = VHOST_VDPA_DEVICE(vdev);
>+ uint32_t vdev_id, max_queue_size;
>+ struct vhost_virtqueue *vqs;
>+ int i, ret;
>+
>+ if (s->vdpa_dev_fd == -1) {
>+ s->vdpa_dev_fd = qemu_open(s->vdpa_dev, O_RDWR, errp);
So, here we are re-opening the `vdpa_dev` again (without checking if it
is NULL).
And we re-do the same ioctls already done in
vhost_vdpa_device_pci_realize(), so I think we should do them in a
single place, and that place should be here.
So, what about doing all the ioctls here, setting appropriate fields in
VhostVdpaDevice, then using that fields in
vhost_vdpa_device_pci_realize() after qdev_realize() to set
`class_code`, `trans_devid`, and `nvectors`?