On Wed, Sep 21, 2022 at 2:00 PM Zhu, Lingshan <lingshan.zhu@xxxxxxxxx> wrote:
>
>
>
> On 9/21/2022 10:17 AM, Jason Wang wrote:
> > On Tue, Sep 20, 2022 at 5:58 PM Zhu, Lingshan <lingshan.zhu@xxxxxxxxx> wrote:
> >>
> >>
> >> On 9/20/2022 10:02 AM, Jason Wang wrote:
> >>> On Fri, Sep 9, 2022 at 5:05 PM Zhu Lingshan <lingshan.zhu@xxxxxxxxx> wrote:
> >>>> This commit adds a new vDPA netlink attribution
> >>>> VDPA_ATTR_VDPA_DEV_SUPPORTED_FEATURES. Userspace can query
> >>>> features of vDPA devices through this new attr.
> >>>>
> >>>> This commit invokes vdpa_config_ops.get_config() than
> >>>> vdpa_get_config_unlocked() to read the device config
> >>>> spcae, so no raeces in vdpa_set_features_unlocked()
> >>>>
> >>>> Signed-off-by: Zhu Lingshan <lingshan.zhu@xxxxxxxxx>
> >>> It's better to share the userspace code as well.
> >> OK, will share it in V2.
> >>>> ---
> >>>> drivers/vdpa/vdpa.c | 19 ++++++++++++++-----
> >>>> include/uapi/linux/vdpa.h | 4 ++++
> >>>> 2 files changed, 18 insertions(+), 5 deletions(-)
> >>>>
> >>>> diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
> >>>> index c06c02704461..798a02c7aa94 100644
> >>>> --- a/drivers/vdpa/vdpa.c
> >>>> +++ b/drivers/vdpa/vdpa.c
> >>>> @@ -491,6 +491,8 @@ static int vdpa_mgmtdev_fill(const struct vdpa_mgmt_dev *mdev, struct sk_buff *m
> >>>> err = -EMSGSIZE;
> >>>> goto msg_err;
> >>>> }
> >>>> +
> >>>> + /* report features of a vDPA management device through VDPA_ATTR_DEV_SUPPORTED_FEATURES */
> >>> The code explains itself, there's no need for the comment.
> >> these comments are required in other discussions
> > I think it's more than sufficient to clarify the semantic where it is defined.
> OK, then only comments in the header file
> >
> >>>> if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_SUPPORTED_FEATURES,
> >>>> mdev->supported_features, VDPA_ATTR_PAD)) {
> >>>> err = -EMSGSIZE;
> >>>> @@ -815,10 +817,10 @@ static int vdpa_dev_net_mq_config_fill(struct vdpa_device *vdev,
> >>>> static int vdpa_dev_net_config_fill(struct vdpa_device *vdev, struct sk_buff *msg)
> >>>> {
> >>>> struct virtio_net_config config = {};
> >>>> - u64 features;
> >>>> + u64 features_device, features_driver;
> >>>> u16 val_u16;
> >>>>
> >>>> - vdpa_get_config_unlocked(vdev, 0, &config, sizeof(config));
> >>>> + vdev->config->get_config(vdev, 0, &config, sizeof(config));
> >>>>
> >>>> if (nla_put(msg, VDPA_ATTR_DEV_NET_CFG_MACADDR, sizeof(config.mac),
> >>>> config.mac))
> >>>> @@ -832,12 +834,19 @@ static int vdpa_dev_net_config_fill(struct vdpa_device *vdev, struct sk_buff *ms
> >>>> if (nla_put_u16(msg, VDPA_ATTR_DEV_NET_CFG_MTU, val_u16))
> >>>> return -EMSGSIZE;
> >>>>
> >>>> - features = vdev->config->get_driver_features(vdev);
> >>>> - if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_NEGOTIATED_FEATURES, features,
> >>>> + features_driver = vdev->config->get_driver_features(vdev);
> >>>> + if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_NEGOTIATED_FEATURES, features_driver,
> >>>> + VDPA_ATTR_PAD))
> >>>> + return -EMSGSIZE;
> >>>> +
> >>>> + features_device = vdev->config->get_device_features(vdev);
> >>>> +
> >>>> + /* report features of a vDPA device through VDPA_ATTR_VDPA_DEV_SUPPORTED_FEATURES */
> >>>> + if (nla_put_u64_64bit(msg, VDPA_ATTR_VDPA_DEV_SUPPORTED_FEATURES, features_device,
> >>>> VDPA_ATTR_PAD))
> >>>> return -EMSGSIZE;
> >>>>
> >>>> - return vdpa_dev_net_mq_config_fill(vdev, msg, features, &config);
> >>>> + return vdpa_dev_net_mq_config_fill(vdev, msg, features_driver, &config);
> >>>> }
> >>>>
> >>>> static int
> >>>> diff --git a/include/uapi/linux/vdpa.h b/include/uapi/linux/vdpa.h
> >>>> index 25c55cab3d7c..97531b52dcbe 100644
> >>>> --- a/include/uapi/linux/vdpa.h
> >>>> +++ b/include/uapi/linux/vdpa.h
> >>>> @@ -46,12 +46,16 @@ enum vdpa_attr {
> >>>>
> >>>> VDPA_ATTR_DEV_NEGOTIATED_FEATURES, /* u64 */
> >>>> VDPA_ATTR_DEV_MGMTDEV_MAX_VQS, /* u32 */
> >>>> + /* features of a vDPA management device */
> >>>> VDPA_ATTR_DEV_SUPPORTED_FEATURES, /* u64 */
> >>>>
> >>>> VDPA_ATTR_DEV_QUEUE_INDEX, /* u32 */
> >>>> VDPA_ATTR_DEV_VENDOR_ATTR_NAME, /* string */
> >>>> VDPA_ATTR_DEV_VENDOR_ATTR_VALUE, /* u64 */
> >>>>
> >>>> + /* features of a vDPA device, e.g., /dev/vhost-vdpa0 */
> >>>> + VDPA_ATTR_VDPA_DEV_SUPPORTED_FEATURES, /* u64 */
> >>> What's the difference between this and VDPA_ATTR_DEV_SUPPORTED_FEATURES?
> >> This is to report a vDPA device features, and
> >> VDPA_ATTR_DEV_SUPPORTED_FEATURES
> >> is used for reporting the management device features, we have a long
> >> discussion
> >> on this before.
> > Yes, but the comment is not clear in many ways:
> >
> > " features of a vDPA management device" sounds like features that is
> > out of the scope of the virtio.
> I think the term "vDPA device" implies that it is a virtio device.
> So how about: "virtio features of a vDPA management device"
Not a native speaker, but how about "virtio features that are
supported by the vDPA management device?"
Thanks
> >
> > And
> >
> > "/dev/vhost-vdpa0" is not a vDPA device but a vhost-vDPA device.
> will remove this example here.
>
> Thanks
> >
> > Thanks
> >
> >>> Thanks
> >>>
> >>>> +
> >>>> /* new attributes must be added above here */
> >>>> VDPA_ATTR_MAX,
> >>>> };
> >>>> --
> >>>> 2.31.1
> >>>>
>
