[PATCH RFC net-next 6/6] net: add uapi for creating lightweight devices

[David Ahern]

Allow users to make new devices lightweight by setting IFLA_LWT_NETDEV
attribute in the newlink request.

Signed-off-by: David Ahern <dsah...@gmail.com>
---
 include/uapi/linux/if_link.h |  1 +
 net/core/rtnetlink.c         | 10 +++++++++-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 8e56ac70e0d1..f57a16e542b7 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -157,6 +157,7 @@ enum {
        IFLA_GSO_MAX_SIZE,
        IFLA_PAD,
        IFLA_XDP,
+       IFLA_LWT_NETDEV,
        __IFLA_MAX
 };
 
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index a4db1cd91c4a..9c18e6dec379 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -2378,6 +2378,7 @@ struct net_device *rtnl_create_link(struct net *net,
        struct net_device *dev;
        unsigned int num_tx_queues = 1;
        unsigned int num_rx_queues = 1;
+       unsigned int flags = 0;
 
        if (tb[IFLA_NUM_TX_QUEUES])
                num_tx_queues = nla_get_u32(tb[IFLA_NUM_TX_QUEUES]);
@@ -2389,8 +2390,15 @@ struct net_device *rtnl_create_link(struct net *net,
        else if (ops->get_num_rx_queues)
                num_rx_queues = ops->get_num_rx_queues();
 
+       if (tb[IFLA_LWT_NETDEV]) {
+               u8 lwt_dev = !!nla_get_u8(tb[IFLA_LWT_NETDEV]);
+
+               if (lwt_dev)
+                       flags |= IFF_LWT_NETDEV;
+       }
+
        dev = alloc_netdev_mqs(ops->priv_size, ifname, name_assign_type,
-                              ops->setup, num_tx_queues, num_rx_queues, 0);
+                              ops->setup, num_tx_queues, num_rx_queues, flags);
        if (!dev)
                return ERR_PTR(-ENOMEM);
 
-- 
2.11.0 (Apple Git-81)