From aefb4d4ad83b608cb8e0cab8d3cd8e57d3f91feb Mon Sep 17 00:00:00 2001 From: Robert Shearman Date: Mon, 16 Jan 2017 14:16:36 +0000 Subject: [PATCH] net: AF-specific RTM_GETSTATS attributes Add the functionality for including address-family-specific per-link stats in RTM_GETSTATS messages. This is done through adding a new IFLA_STATS_AF_SPEC attribute under which address family attributes are nested and then the AF-specific attributes can be further nested. This follows the model of IFLA_AF_SPEC on RTM_*LINK messages and it has the advantage of presenting an easily extended hierarchy. The rtnl_af_ops structure is extended to provide AFs with the opportunity to fill and provide the size of their stats attributes. One alternative would have been to provide AFs with the ability to add attributes directly into the RTM_GETSTATS message without a nested hierarchy. I discounted this approach as it increases the rate at which the 32 attribute number space is used up and it makes implementation a little more tricky for stats dump resuming (at the moment the order in which attributes are added to the message has to match the numeric order of the attributes). Another alternative would have been to register per-AF RTM_GETSTATS handlers. I discounted this approach as I perceived a common use-case to be getting all the stats for an interface and this approach would necessitate multiple requests/dumps to retrieve them all. Signed-off-by: Robert Shearman Acked-by: Roopa Prabhu Signed-off-by: David S. Miller --- include/net/rtnetlink.h | 4 ++++ include/uapi/linux/if_link.h | 1 + net/core/rtnetlink.c | 50 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 55 insertions(+) diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h index 4113916..106de5f 100644 --- a/include/net/rtnetlink.h +++ b/include/net/rtnetlink.h @@ -139,6 +139,10 @@ struct rtnl_af_ops { const struct nlattr *attr); int (*set_link_af)(struct net_device *dev, const struct nlattr *attr); + + int (*fill_stats_af)(struct sk_buff *skb, + const struct net_device *dev); + size_t (*get_stats_af_size)(const struct net_device *dev); }; void __rtnl_af_unregister(struct rtnl_af_ops *ops); diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index 6b13e59..184b16e 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -847,6 +847,7 @@ enum { IFLA_STATS_LINK_XSTATS, IFLA_STATS_LINK_XSTATS_SLAVE, IFLA_STATS_LINK_OFFLOAD_XSTATS, + IFLA_STATS_AF_SPEC, __IFLA_STATS_MAX, }; diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 75e3ea7..f538f76 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -3829,6 +3829,39 @@ static int rtnl_fill_statsinfo(struct sk_buff *skb, struct net_device *dev, *idxattr = 0; } + if (stats_attr_valid(filter_mask, IFLA_STATS_AF_SPEC, *idxattr)) { + struct rtnl_af_ops *af_ops; + + *idxattr = IFLA_STATS_AF_SPEC; + attr = nla_nest_start(skb, IFLA_STATS_AF_SPEC); + if (!attr) + goto nla_put_failure; + + list_for_each_entry(af_ops, &rtnl_af_ops, list) { + if (af_ops->fill_stats_af) { + struct nlattr *af; + int err; + + af = nla_nest_start(skb, af_ops->family); + if (!af) + goto nla_put_failure; + + err = af_ops->fill_stats_af(skb, dev); + + if (err == -ENODATA) + nla_nest_cancel(skb, af); + else if (err < 0) + goto nla_put_failure; + + nla_nest_end(skb, af); + } + } + + nla_nest_end(skb, attr); + + *idxattr = 0; + } + nlmsg_end(skb, nlh); return 0; @@ -3885,6 +3918,23 @@ static size_t if_nlmsg_stats_size(const struct net_device *dev, if (stats_attr_valid(filter_mask, IFLA_STATS_LINK_OFFLOAD_XSTATS, 0)) size += rtnl_get_offload_stats_size(dev); + if (stats_attr_valid(filter_mask, IFLA_STATS_AF_SPEC, 0)) { + struct rtnl_af_ops *af_ops; + + /* for IFLA_STATS_AF_SPEC */ + size += nla_total_size(0); + + list_for_each_entry(af_ops, &rtnl_af_ops, list) { + if (af_ops->get_stats_af_size) { + size += nla_total_size( + af_ops->get_stats_af_size(dev)); + + /* for AF_* */ + size += nla_total_size(0); + } + } + } + return size; } -- 2.7.4