From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Graf Subject: [RFC] tcf_bind_filter failure handling Date: Mon, 13 Dec 2004 17:53:02 +0100 Message-ID: <20041213165302.GE8493@postel.suug.ch> References: <20041109161126.376f755c.davem@davemloft.net> <20041110010113.GJ31969@postel.suug.ch> <41916A91.3080107@trash.net> <20041110012251.GK31969@postel.suug.ch> <41916F0B.5010809@trash.net> <20041110013941.GL31969@postel.suug.ch> <41917330.6090002@trash.net> <20041212175736.GA8493@postel.suug.ch> <41BC8819.7040501@trash.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "David S. Miller" , Herbert Xu , netdev@oss.sgi.com Return-path: To: Patrick McHardy Content-Disposition: inline In-Reply-To: <41BC8819.7040501@trash.net> Sender: netdev-bounce@oss.sgi.com Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org The handling of a failure in tcf_bind_filter is inconsistent. u32: ignore fw: ignore route: ignore rsvp: ignore tcindex: error It might be a good idea to make this consistent. So in order to validate the classid before making any changes we could simply lock it via get (see patch below), return an error if it fails and put it back in case of an error further in the path or after binding the filter. Bindings not only locks the class from removal while a filter is pointing to it. It speeds up classyfing by saving a lookup for every tc_classify call. It's not really a problem if the class is not locked, the qdisc will look it up and falls back to a default class if it doesn't exists so it's rather a cosmetic/policy thing. Note: The patch below is not intented for inclusion yet and will not apply since I made local changes to pkt_cls.h. --- linux-2.6.10-rc3-bk6.orig/include/net/pkt_cls.h 2004-12-12 21:54:03.000000000 +0100 +++ linux-2.6.10-rc3-bk6/include/net/pkt_cls.h 2004-12-13 16:40:06.000000000 +0100 @@ -62,6 +62,18 @@ tp->q->ops->cl_ops->unbind_tcf(tp->q, cl); } +static inline unsigned long +tcf_class_get(struct tcf_proto *tp, u32 classid) +{ + return tp->q->ops->cl_ops->get(tp->q, classid); +} + +static inline void +tcf_class_put(struct tcf_proto *tp, unsigned long cl) +{ + tp->q->ops->cl_ops->put(tp->q, cl); +} + #ifdef CONFIG_NET_CLS_ACT static inline int tcf_validate_act_police(struct rtattr *act_police_tlv, struct rtattr *rate_tlv,