Re: [PATCH 1/2] vdpa: support set mac address from vdpa tool

Michael S. Tsirkin
2024-06-12T07:12:56Z

On Tue, Jun 11, 2024 at 01:32:32PM +0800, Cindy Lu wrote:
> Add new UAPI to support the mac address from vdpa tool

The patch does not do what commit log says.
Instead there's an internal API to set mac and
a UAPI to write into config space.

> 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>
> ---
> 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(struct 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 = {};
> + struct nlattr **nl_attrs = info->attrs;
> + struct vdpa_mgmt_dev *mdev;
> + const u8 *macaddr;
> + const char *name;
> + int err = 0;
> + struct device *dev;
> + struct vdpa_device *vdev;
> +
> + if (!info->attrs[VDPA_ATTR_DEV_NAME])
> + return -EINVAL;
> +
> + name = nla_data(info->attrs[VDPA_ATTR_DEV_NAME]);
> +
> + down_write(&vdpa_dev_lock);
> + dev = bus_find_device(&vdpa_bus, NULL, name, vdpa_name_match);
> + if (!dev) {
> + NL_SET_ERR_MSG_MOD(info->extack, "device not found");
> + err = -ENODEV;
> + goto dev_err;
> + }
> + vdev = 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 = -EINVAL;
> + goto mdev_err;
> + }
> + mdev = vdev->mdev;
> + if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MACADDR]) {
> + if (!(mdev->supported_features & BIT_ULL(VIRTIO_NET_F_MAC))) {

Seems to poke at a device without even making sure it's a network
device.

> + NL_SET_ERR_MSG_FMT_MOD(
> + info->extack,
> + "Missing features 0x%llx for provided attributes",
> + BIT_ULL(VIRTIO_NET_F_MAC));
> + err = -EINVAL;
> + goto mdev_err;
> + }
> + macaddr = nla_data(nl_attrs[VDPA_ATTR_DEV_NET_CFG_MACADDR]);
> + memcpy(set_config.net.mac, macaddr, ETH_ALEN);
> + set_config.mask |= BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MACADDR);
> + if (mdev->ops->set_mac) {
> + err = mdev->ops->set_mac(mdev, vdev, &set_config);
> + } 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 = container_of(dev, struct vdpa_device, dev);
> @@ -1285,6 +1351,11 @@ static const struct genl_ops vdpa_nl_ops[] = {
> .doit = vdpa_nl_cmd_dev_stats_get_doit,
> .flags = GENL_ADMIN_PERM,
> },
> + {
> + .cmd = VDPA_CMD_DEV_CONFIG_SET,
> + .doit = vdpa_nl_cmd_dev_config_set_doit,
> + .flags = GENL_ADMIN_PERM,
> + },
> };
>
> static struct genl_family vdpa_nl_family __ro_after_init = {
> 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 *dev);
> + int (*set_mac)(struct vdpa_mgmt_dev *mdev, struct vdpa_device *dev,
> + const struct vdpa_dev_set_config *config);

Well, now vdpa_mgmtdev_ops which was completely generic is growing
a net specific interface. Which begs a question - how is this
going to work with other device types?

> };
>
> /**
> 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