Re: [PATCH 5/6] vdpa: introduce virtio pci driver

From: Jason Wang
Date: Tue Jun 02 2020 - 03:09:26 EST



On 2020/6/2 äå1:08, Michael S. Tsirkin wrote:
On Fri, May 29, 2020 at 04:03:02PM +0800, Jason Wang wrote:
+static void vp_vdpa_set_vq_ready(struct vdpa_device *vdpa,
+ u16 qid, bool ready)
+{
+ struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
+
+ vp_iowrite16(qid, &vp_vdpa->common->queue_select);
+ vp_iowrite16(ready, &vp_vdpa->common->queue_enable);
+}
+
Looks like this needs to check and just skip the write if
ready == 0, right? Of course vdpa core then insists on calling
vp_vdpa_get_vq_ready which will warn. Maybe just drop the
check from core, move it to drivers which need it?

...


That may work, but it may cause inconsistent semantic for set_vq_ready if we leave it to the driver.




+static const struct pci_device_id vp_vdpa_id_table[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_REDHAT_QUMRANET, PCI_ANY_ID) },
+ { 0 }
+};
This looks like it'll create a mess with either virtio pci
or vdpa being loaded at random. Maybe just don't specify
any IDs for now. Down the road we could get a
distinct vendor ID or a range of device IDs for this.


Right, will do.

Thanks



+MODULE_DEVICE_TABLE(pci, vp_vdpa_id_table);
+
+static struct pci_driver vp_vdpa_driver = {
+ .name = "vp-vdpa",
+ .id_table = vp_vdpa_id_table,
+ .probe = vp_vdpa_probe,
+ .remove = vp_vdpa_remove,
+};
+
+module_pci_driver(vp_vdpa_driver);
+
+MODULE_AUTHOR("Jason Wang <jasowang@xxxxxxxxxx>");
+MODULE_DESCRIPTION("vp-vdpa");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("1");
--
2.20.1