| Message ID | 20250308155440.267782-2-maxime.chevallier@bootlin.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | net: ethtool: Introduce ethnl dump helpers | expand |
On Sat, 8 Mar 2025 16:54:33 +0100 Maxime Chevallier <maxime.chevallier@bootlin.com> wrote: > We have a number of netlink commands in the ethnl family that may have > multiple objects to dump even for a single net_device, including : > > - PLCA, PSE-PD, phy: one message per PHY device > - tsinfo: one message per timestamp source (netdev + phys) > - rss: One per RSS context > > To get this behaviour, these netlink commands need to roll a custom > ->dumpit(). > > To prepare making per-netdev DUMP more generic in ethnl, introduce a > member in the ethnl ops to indicate if a given command may allow > pernetdev DUMPs (also referred to as filtered DUMPs). > > Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com> > --- > V2: - Rebase > - Fix kdoc > - Fix bissectabilitu by using the right function names > > net/ethtool/netlink.c | 45 ++++++++++++++++++++++++++++--------------- > net/ethtool/netlink.h | 2 ++ > 2 files changed, 31 insertions(+), 16 deletions(-) > > diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c > index 70834947f474..11e4122b7707 100644 > --- a/net/ethtool/netlink.c > +++ b/net/ethtool/netlink.c > @@ -586,21 +586,34 @@ static int ethnl_default_dumpit(struct sk_buff *skb, > int ret = 0; > > rcu_read_lock(); > - for_each_netdev_dump(net, dev, ctx->pos_ifindex) { > - dev_hold(dev); > + if (ctx->req_info->dev) { > + dev = ctx->req_info->dev; > rcu_read_unlock(); > - > - ret = ethnl_default_dump_one(skb, dev, ctx, > genl_info_dump(cb)); - > + /* Filtered DUMP request targeted to a single netdev. We > already > + * hold a ref to the netdev from ->start() > + */ > + ret = ethnl_default_dump_one(skb, dev, ctx, > + genl_info_dump(cb)); > rcu_read_lock(); > - dev_put(dev); > - > - if (ret < 0 && ret != -EOPNOTSUPP) { > - if (likely(skb->len)) > - ret = skb->len; > - break; You are not checking -EOPNOTSUPP, so you can return this error in the ctx->req_info->dev condition. I am not sure about the policy but do we want to report the EOPNOTSUPP error in the dump command instead of simply returning nothing. Regards,
diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c index 70834947f474..11e4122b7707 100644 --- a/net/ethtool/netlink.c +++ b/net/ethtool/netlink.c @@ -586,21 +586,34 @@ static int ethnl_default_dumpit(struct sk_buff *skb, int ret = 0; rcu_read_lock(); - for_each_netdev_dump(net, dev, ctx->pos_ifindex) { - dev_hold(dev); + if (ctx->req_info->dev) { + dev = ctx->req_info->dev; rcu_read_unlock(); - - ret = ethnl_default_dump_one(skb, dev, ctx, genl_info_dump(cb)); - + /* Filtered DUMP request targeted to a single netdev. We already + * hold a ref to the netdev from ->start() + */ + ret = ethnl_default_dump_one(skb, dev, ctx, + genl_info_dump(cb)); rcu_read_lock(); - dev_put(dev); - - if (ret < 0 && ret != -EOPNOTSUPP) { - if (likely(skb->len)) - ret = skb->len; - break; + netdev_put(ctx->req_info->dev, &ctx->req_info->dev_tracker); + } else { + for_each_netdev_dump(net, dev, ctx->pos_ifindex) { + dev_hold(dev); + rcu_read_unlock(); + + ret = ethnl_default_dump_one(skb, dev, ctx, + genl_info_dump(cb)); + + rcu_read_lock(); + dev_put(dev); + + if (ret < 0 && ret != -EOPNOTSUPP) { + if (likely(skb->len)) + ret = skb->len; + break; + } + ret = 0; } - ret = 0; } rcu_read_unlock(); @@ -634,10 +647,10 @@ static int ethnl_default_start(struct netlink_callback *cb) } ret = ethnl_default_parse(req_info, &info->info, ops, false); - if (req_info->dev) { - /* We ignore device specification in dump requests but as the - * same parser as for non-dump (doit) requests is used, it - * would take reference to the device if it finds one + if (req_info->dev && !ops->allow_pernetdev_dump) { + /* We ignore device specification in unfiltered dump requests + * but as the same parser as for non-dump (doit) requests is + * used, it would take reference to the device if it finds one */ netdev_put(req_info->dev, &req_info->dev_tracker); req_info->dev = NULL; diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h index ec6ab5443a6f..4aaa73282d6a 100644 --- a/net/ethtool/netlink.h +++ b/net/ethtool/netlink.h @@ -331,6 +331,7 @@ int ethnl_sock_priv_set(struct sk_buff *skb, struct net_device *dev, u32 portid, * @req_info_size: size of request info * @reply_data_size: size of reply data * @allow_nodev_do: allow non-dump request with no device identification + * @allow_pernetdev_dump: allow filtering dump requests with ifname/ifindex * @set_ntf_cmd: notification to generate on changes (SET) * @parse_request: * Parse request except common header (struct ethnl_req_info). Common @@ -388,6 +389,7 @@ struct ethnl_request_ops { unsigned int req_info_size; unsigned int reply_data_size; bool allow_nodev_do; + bool allow_pernetdev_dump; u8 set_ntf_cmd; int (*parse_request)(struct ethnl_req_info *req_info,
We have a number of netlink commands in the ethnl family that may have multiple objects to dump even for a single net_device, including : - PLCA, PSE-PD, phy: one message per PHY device - tsinfo: one message per timestamp source (netdev + phys) - rss: One per RSS context To get this behaviour, these netlink commands need to roll a custom ->dumpit(). To prepare making per-netdev DUMP more generic in ethnl, introduce a member in the ethnl ops to indicate if a given command may allow pernetdev DUMPs (also referred to as filtered DUMPs). Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com> --- V2: - Rebase - Fix kdoc - Fix bissectabilitu by using the right function names net/ethtool/netlink.c | 45 ++++++++++++++++++++++++++++--------------- net/ethtool/netlink.h | 2 ++ 2 files changed, 31 insertions(+), 16 deletions(-)