From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Westphal Subject: Re: [PATCH 0/2] constify nf_hook_ops structures Date: Sat, 29 Jul 2017 11:41:36 +0200 Message-ID: <20170729094136.GG28392@breakpoint.cc> References: <1501310455-7896-1-git-send-email-Julia.Lawall@lip6.fr> <20170729084429.GE28392@breakpoint.cc> <20170729091618.GF28392@breakpoint.cc> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Florian Westphal , linux-decnet-user@lists.sourceforge.net, bhumirks@gmail.com, kernel-janitors@vger.kernel.org, Pablo Neira Ayuso , Jozsef Kadlecsik , "David S. Miller" , netfilter-devel@vger.kernel.org, coreteam@netfilter.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: Julia Lawall Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Julia Lawall wrote: > On Sat, 29 Jul 2017, Florian Westphal wrote: > > From a quick glance I don't see why we can't e.g. constify > > nf_conntrack_l3/4_proto too. It is not going to be as simple > > as just placing const everywhere, but I see no requirement for > > having these writeable. > > I will take a look. Thanks. nf_logger and nf_loginfo also look like constify candidates. If there is a way to add "const" qualifier to pointer-to-structs that are not modified this would good as well to have IMO, if just for purpose of documentation. For instance: +++ b/net/netfilter/nf_conntrack_core.c @@ -1177,8 +1177,8 @@ void nf_conntrack_free(struct nf_conn *ct) static noinline struct nf_conntrack_tuple_hash * init_conntrack(struct net *net, struct nf_conn *tmpl, const struct nf_conntrack_tuple *tuple, - struct nf_conntrack_l3proto *l3proto, - struct nf_conntrack_l4proto *l4proto, + const struct nf_conntrack_l3proto *l3proto, + const struct nf_conntrack_l4proto *l4proto, (its only passed as arg to a function that expects "const struct nf_conntrack_x *"). I think we have several (also non-static helpers) that take "struct foo *" arg while they could use "const struct foo*" instead.