Re: [PATCH net-next v7 2/4] netlink: changes for setting and clearing protodown via netlink.

[Stephen Hemminger <stephen@networkplumber.org>]

On Tue, 14 Jul 2015 13:43:20 -0700
anuradhak@cumulusnetworks.com wrote:

> From: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
> 
> Signed-off-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
> Signed-off-by: Andy Gospodarek <gospo@cumulusnetworks.com>
> Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
> Signed-off-by: Wilson Kok <wkok@cumulusnetworks.com>
> ---
>  include/uapi/linux/if_link.h |    1 +
>  net/core/rtnetlink.c         |   16 ++++++++++++++--
>  2 files changed, 15 insertions(+), 2 deletions(-)
> 
> diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
> index 2c7e8e3..24d68b7 100644
> --- a/include/uapi/linux/if_link.h
> +++ b/include/uapi/linux/if_link.h
> @@ -148,6 +148,7 @@ enum {
>  	IFLA_PHYS_SWITCH_ID,
>  	IFLA_LINK_NETNSID,
>  	IFLA_PHYS_PORT_NAME,
> +	IFLA_PROTO_DOWN,
>  	__IFLA_MAX
>  };
>  
> diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
> index 01ced4a..4104e27 100644
> --- a/net/core/rtnetlink.c
> +++ b/net/core/rtnetlink.c
> @@ -896,7 +896,9 @@ static noinline size_t if_nlmsg_size(const struct net_device *dev,
>  	       + rtnl_link_get_size(dev) /* IFLA_LINKINFO */
>  	       + rtnl_link_get_af_size(dev) /* IFLA_AF_SPEC */
>  	       + nla_total_size(MAX_PHYS_ITEM_ID_LEN) /* IFLA_PHYS_PORT_ID */
> -	       + nla_total_size(MAX_PHYS_ITEM_ID_LEN); /* IFLA_PHYS_SWITCH_ID */
> +	       + nla_total_size(MAX_PHYS_ITEM_ID_LEN) /* IFLA_PHYS_SWITCH_ID */
> +	       + nla_total_size(1); /* IFLA_PROTO_DOWN */
> +
>  }
>  
>  static int rtnl_vf_ports_fill(struct sk_buff *skb, struct net_device *dev)
> @@ -1082,7 +1084,8 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
>  	    (dev->ifalias &&
>  	     nla_put_string(skb, IFLA_IFALIAS, dev->ifalias)) ||
>  	    nla_put_u32(skb, IFLA_CARRIER_CHANGES,
> -			atomic_read(&dev->carrier_changes)))
> +			atomic_read(&dev->carrier_changes)) ||
> +	    nla_put_u8(skb, IFLA_PROTO_DOWN, dev->proto_down))
>  		goto nla_put_failure;
>  
>  	if (1) {
> @@ -1319,6 +1322,7 @@ static const struct nla_policy ifla_policy[IFLA_MAX+1] = {
>  	[IFLA_CARRIER_CHANGES]	= { .type = NLA_U32 },  /* ignored */
>  	[IFLA_PHYS_SWITCH_ID]	= { .type = NLA_BINARY, .len = MAX_PHYS_ITEM_ID_LEN },
>  	[IFLA_LINK_NETNSID]	= { .type = NLA_S32 },
> +	[IFLA_PROTO_DOWN]	= { .type = NLA_U8 },
>  };
>  
>  static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {
> @@ -1853,6 +1857,14 @@ static int do_setlink(const struct sk_buff *skb,
>  	}
>  	err = 0;
>  
> +	if (tb[IFLA_PROTO_DOWN]) {
> +		err = dev_change_proto_down(dev,
> +					    nla_get_u8(tb[IFLA_PROTO_DOWN]));
> +		if (err)
> +			goto errout;
> +		status |= DO_SETLINK_NOTIFY;
> +	}
> +
>  errout:
>  	if (status & DO_SETLINK_MODIFIED) {
>  		if (status & DO_SETLINK_NOTIFY)

Why is this it's own attribute rather than a flag?