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From: Cindy Lu <lulu@redhat.com>
Date: Thu, 13 Jun 2024 21:29:04 +0800
Message-ID: <CACLfguWwkkfFA143uOavS0jDkW1Q0XEd5JZDdriOz-yywDkYng@mail.gmail.com>
Subject: Re: [PATCH 1/2] vdpa: support set mac address from vdpa tool
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: dtatulea@nvidia.com, jasowang@redhat.com, 
	virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, 
	kvm@vger.kernel.org, netdev@vger.kernel.org
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On Thu, Jun 13, 2024 at 2:59=E2=80=AFPM Michael S. Tsirkin <mst@redhat.com>=
 wrote:
>
> On Tue, Jun 11, 2024 at 01:32:32PM +0800, Cindy Lu wrote:
> > Add new UAPI to support the mac address from vdpa tool
> > Function vdpa_nl_cmd_dev_config_set_doit() will get the
> > MAC address from the vdpa tool and then set it to the device.
> >
> > The usage is: vdpa dev set name vdpa_name mac **:**:**:**:**:**
> >
> > Here is sample:
> > root@L1# vdpa -jp dev config show vdpa0
> > {
> >     "config": {
> >         "vdpa0": {
> >             "mac": "82:4d:e9:5d:d7:e6",
> >             "link ": "up",
> >             "link_announce ": false,
> >             "mtu": 1500
> >         }
> >     }
> > }
> >
> > root@L1# vdpa dev set name vdpa0 mac 00:11:22:33:44:55
> >
> > root@L1# vdpa -jp dev config show vdpa0
> > {
> >     "config": {
> >         "vdpa0": {
> >             "mac": "00:11:22:33:44:55",
> >             "link ": "up",
> >             "link_announce ": false,
> >             "mtu": 1500
> >         }
> >     }
> > }
> >
> > Signed-off-by: Cindy Lu <lulu@redhat.com>
>
>
>
> I think actually the idea of allowing provisioning
> by specifying config of the device is actually valid.
> However
> - the name SET_CONFIG makes people think this allows
>   writing even when e.g. device is assigned to guest
> - having the internal api be mac specific is weird
>
> Shouldn't config be an attribute maybe, not a new command?
>
Got it. Thanks, Michael. I will change this.
Thanks
Cindy
>
> > ---
> >  drivers/vdpa/vdpa.c       | 71 +++++++++++++++++++++++++++++++++++++++
> >  include/linux/vdpa.h      |  2 ++
> >  include/uapi/linux/vdpa.h |  1 +
> >  3 files changed, 74 insertions(+)
> >
> > diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
> > index a7612e0783b3..347ae6e7749d 100644
> > --- a/drivers/vdpa/vdpa.c
> > +++ b/drivers/vdpa/vdpa.c
> > @@ -1149,6 +1149,72 @@ static int vdpa_nl_cmd_dev_config_get_doit(struc=
t sk_buff *skb, struct genl_info
> >       return err;
> >  }
> >
> > +static int vdpa_nl_cmd_dev_config_set_doit(struct sk_buff *skb,
> > +                                        struct genl_info *info)
> > +{
> > +     struct vdpa_dev_set_config set_config =3D {};
> > +     struct nlattr **nl_attrs =3D info->attrs;
> > +     struct vdpa_mgmt_dev *mdev;
> > +     const u8 *macaddr;
> > +     const char *name;
> > +     int err =3D 0;
> > +     struct device *dev;
> > +     struct vdpa_device *vdev;
> > +
> > +     if (!info->attrs[VDPA_ATTR_DEV_NAME])
> > +             return -EINVAL;
> > +
> > +     name =3D nla_data(info->attrs[VDPA_ATTR_DEV_NAME]);
> > +
> > +     down_write(&vdpa_dev_lock);
> > +     dev =3D bus_find_device(&vdpa_bus, NULL, name, vdpa_name_match);
> > +     if (!dev) {
> > +             NL_SET_ERR_MSG_MOD(info->extack, "device not found");
> > +             err =3D -ENODEV;
> > +             goto dev_err;
> > +     }
> > +     vdev =3D container_of(dev, struct vdpa_device, dev);
> > +     if (!vdev->mdev) {
> > +             NL_SET_ERR_MSG_MOD(
> > +                     info->extack,
> > +                     "Fail to find the specified management device");
> > +             err =3D -EINVAL;
> > +             goto mdev_err;
> > +     }
> > +     mdev =3D vdev->mdev;
> > +     if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MACADDR]) {
> > +             if (!(mdev->supported_features & BIT_ULL(VIRTIO_NET_F_MAC=
))) {
> > +                     NL_SET_ERR_MSG_FMT_MOD(
> > +                             info->extack,
> > +                             "Missing features 0x%llx for provided att=
ributes",
> > +                             BIT_ULL(VIRTIO_NET_F_MAC));
> > +                     err =3D -EINVAL;
> > +                     goto mdev_err;
> > +             }
> > +             macaddr =3D nla_data(nl_attrs[VDPA_ATTR_DEV_NET_CFG_MACAD=
DR]);
> > +             memcpy(set_config.net.mac, macaddr, ETH_ALEN);
> > +             set_config.mask |=3D BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MACADD=
R);
> > +             if (mdev->ops->set_mac) {
> > +                     err =3D mdev->ops->set_mac(mdev, vdev, &set_confi=
g);
> > +             } else {
> > +                     NL_SET_ERR_MSG_FMT_MOD(
> > +                             info->extack,
> > +                             "%s device not support set mac address ",=
 name);
> > +             }
> > +
> > +     } else {
> > +             NL_SET_ERR_MSG_FMT_MOD(info->extack,
> > +                                    "%s device not support this config=
 ",
> > +                                    name);
> > +     }
> > +
> > +mdev_err:
> > +     put_device(dev);
> > +dev_err:
> > +     up_write(&vdpa_dev_lock);
> > +     return err;
> > +}
> > +
> >  static int vdpa_dev_config_dump(struct device *dev, void *data)
> >  {
> >       struct vdpa_device *vdev =3D container_of(dev, struct vdpa_device=
, dev);
> > @@ -1285,6 +1351,11 @@ static const struct genl_ops vdpa_nl_ops[] =3D {
> >               .doit =3D vdpa_nl_cmd_dev_stats_get_doit,
> >               .flags =3D GENL_ADMIN_PERM,
> >       },
> > +     {
> > +             .cmd =3D VDPA_CMD_DEV_CONFIG_SET,
> > +             .doit =3D vdpa_nl_cmd_dev_config_set_doit,
> > +             .flags =3D GENL_ADMIN_PERM,
> > +     },
> >  };
> >
> >  static struct genl_family vdpa_nl_family __ro_after_init =3D {
> > diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
> > index db15ac07f8a6..c97f4f1da753 100644
> > --- a/include/linux/vdpa.h
> > +++ b/include/linux/vdpa.h
> > @@ -581,6 +581,8 @@ struct vdpa_mgmtdev_ops {
> >       int (*dev_add)(struct vdpa_mgmt_dev *mdev, const char *name,
> >                      const struct vdpa_dev_set_config *config);
> >       void (*dev_del)(struct vdpa_mgmt_dev *mdev, struct vdpa_device *d=
ev);
> > +     int (*set_mac)(struct vdpa_mgmt_dev *mdev, struct vdpa_device *de=
v,
> > +                    const struct vdpa_dev_set_config *config);
> >  };
> >
> >  /**
> > diff --git a/include/uapi/linux/vdpa.h b/include/uapi/linux/vdpa.h
> > index 54b649ab0f22..53f249fb26bc 100644
> > --- a/include/uapi/linux/vdpa.h
> > +++ b/include/uapi/linux/vdpa.h
> > @@ -19,6 +19,7 @@ enum vdpa_command {
> >       VDPA_CMD_DEV_GET,               /* can dump */
> >       VDPA_CMD_DEV_CONFIG_GET,        /* can dump */
> >       VDPA_CMD_DEV_VSTATS_GET,
> > +     VDPA_CMD_DEV_CONFIG_SET,
> >  };
> >
> >  enum vdpa_attr {
> > --
> > 2.45.0
>