From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756365AbZDJW4t (ORCPT ); Fri, 10 Apr 2009 18:56:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752213AbZDJW4i (ORCPT ); Fri, 10 Apr 2009 18:56:38 -0400 Received: from e32.co.us.ibm.com ([32.97.110.150]:43203 "EHLO e32.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751083AbZDJW4i (ORCPT ); Fri, 10 Apr 2009 18:56:38 -0400 Date: Fri, 10 Apr 2009 17:56:36 -0500 From: "Serge E. Hallyn" To: Alexey Dobriyan Cc: akpm@linux-foundation.org, containers@lists.linux-foundation.org, xemul@parallels.com, dave@linux.vnet.ibm.com, mingo@elte.hu, orenl@cs.columbia.edu, hch@infradead.org, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 07/30] netns: extract net_create() Message-ID: <20090410225636.GD13873@us.ibm.com> References: <20090410023448.GH27788@x200.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090410023448.GH27788@x200.localdomain> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Quoting Alexey Dobriyan (adobriyan@gmail.com): > net_create() will be used by C/R code to create fresh netns on restart. > > Signed-off-by: Alexey Dobriyan Acked-by: Serge Hallyn Although this ends up making a new assumption that setup_net(), and therefore the pernet_ops->init() functions, do not return error > 0. There's nothing actually stopping that (outside of code review, but there appears to be no comment anywhere saying that's uncooth). If it returns > 0, then we return the ns as though it were valid, but don't add it to the list of namespaces... Do we care? -serge > --- > > include/net/net_namespace.h | 1 + > net/core/net_namespace.c | 44 ++++++++++++++++++++------------------------ > 2 files changed, 21 insertions(+), 24 deletions(-) > > --- a/include/net/net_namespace.h > +++ b/include/net/net_namespace.h > @@ -107,6 +107,7 @@ static inline struct net *copy_net_ns(unsigned long flags, struct net *net_ns) > extern struct list_head net_namespace_list; > > #ifdef CONFIG_NET_NS > +struct net *net_create(void); > extern void __put_net(struct net *net); > > static inline struct net *get_net(struct net *net) > --- a/net/core/net_namespace.c > +++ b/net/core/net_namespace.c > @@ -115,38 +115,34 @@ static void net_free(struct net *net) > kmem_cache_free(net_cachep, net); > } > > -struct net *copy_net_ns(unsigned long flags, struct net *old_net) > +struct net *net_create(void) > { > - struct net *new_net = NULL; > - int err; > - > - if (!(flags & CLONE_NEWNET)) > - return get_net(old_net); > - > - err = -ENOMEM; > - new_net = net_alloc(); > - if (!new_net) > - goto out_err; > + struct net *net; > + int rv; > > + net = net_alloc(); > + if (!net) > + return ERR_PTR(-ENOMEM); > mutex_lock(&net_mutex); > - err = setup_net(new_net); > - if (!err) { > + rv = setup_net(net); > + if (rv == 0) { > rtnl_lock(); > - list_add_tail(&new_net->list, &net_namespace_list); > + list_add_tail(&net->list, &net_namespace_list); > rtnl_unlock(); > } > mutex_unlock(&net_mutex); > + if (rv < 0) { > + net_free(net); > + return ERR_PTR(rv); > + } > + return net; > +} > > - if (err) > - goto out_free; > -out: > - return new_net; > - > -out_free: > - net_free(new_net); > -out_err: > - new_net = ERR_PTR(err); > - goto out; > +struct net *copy_net_ns(unsigned long flags, struct net *old_net) > +{ > + if (!(flags & CLONE_NEWNET)) > + return get_net(old_net); > + return net_create(); > } > > static void cleanup_net(struct work_struct *work)