Return-Path: Received: from mail-qg0-f45.google.com ([209.85.192.45]:34693 "EHLO mail-qg0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756226AbcEELAW (ORCPT ); Thu, 5 May 2016 07:00:22 -0400 Received: by mail-qg0-f45.google.com with SMTP id 90so37454451qgz.1 for ; Thu, 05 May 2016 04:00:21 -0700 (PDT) Message-ID: <1462446017.28919.7.camel@poochiereds.net> Subject: Re: [PATCH] nfsd: handle seqid wraparound in nfsd4_preprocess_layout_stateid From: Jeff Layton To: bfields@fieldses.org Cc: linux-nfs@vger.kernel.org, Christoph Hellwig Date: Thu, 05 May 2016 07:00:17 -0400 In-Reply-To: <1462445627-15093-1-git-send-email-jeff.layton@primarydata.com> References: <1462445627-15093-1-git-send-email-jeff.layton@primarydata.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-nfs-owner@vger.kernel.org List-ID: On Thu, 2016-05-05 at 06:53 -0400, Jeff Layton wrote: > Move the existing static function to an inline helper, and call it. > > Cc: Christoph Hellwig > Signed-off-by: Jeff Layton This is just something I noticed by inspection while ensuring that some client-side changes that I have queued won't cause a problem. I don't have a knfsd pnfs test rig though, so I can't test this easily. As a side note though...should we also be verifying that the seqid is not zero in this function? That's never allowed for layout stateids. > --- >  fs/nfsd/nfs4layouts.c | 2 +- >  fs/nfsd/nfs4state.c   | 8 +------- >  fs/nfsd/state.h       | 5 +++++ >  3 files changed, 7 insertions(+), 8 deletions(-) > > diff --git a/fs/nfsd/nfs4layouts.c b/fs/nfsd/nfs4layouts.c > index 825c7bc8d789..953c0755cb37 100644 > --- a/fs/nfsd/nfs4layouts.c > +++ b/fs/nfsd/nfs4layouts.c > @@ -289,7 +289,7 @@ nfsd4_preprocess_layout_stateid(struct svc_rqst *rqstp, >   >   status = nfserr_bad_stateid; >   mutex_lock(&ls->ls_mutex); > - if (stateid->si_generation > stid->sc_stateid.si_generation) > + if (nfsd4_stateid_generation_after(stateid, &stid->sc_stateid)) >   goto out_unlock_stid; >   if (layout_type != ls->ls_layout_type) >   goto out_unlock_stid; > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > index 0462eeddfff9..f5f82e145018 100644 > --- a/fs/nfsd/nfs4state.c > +++ b/fs/nfsd/nfs4state.c > @@ -4651,12 +4651,6 @@ grace_disallows_io(struct net *net, struct inode *inode) >   return opens_in_grace(net) && mandatory_lock(inode); >  } >   > -/* Returns true iff a is later than b: */ > -static bool stateid_generation_after(stateid_t *a, stateid_t *b) > -{ > - return (s32)(a->si_generation - b->si_generation) > 0; > -} > - >  static __be32 check_stateid_generation(stateid_t *in, stateid_t *ref, bool has_session) >  { >   /* > @@ -4670,7 +4664,7 @@ static __be32 check_stateid_generation(stateid_t *in, stateid_t *ref, bool has_s >   return nfs_ok; >   >   /* If the client sends us a stateid from the future, it's buggy: */ > - if (stateid_generation_after(in, ref)) > + if (nfsd4_stateid_generation_after(in, ref)) >   return nfserr_bad_stateid; >   /* >    * However, we could see a stateid from the past, even from a > diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h > index c050c53036a6..986e51e5ceac 100644 > --- a/fs/nfsd/state.h > +++ b/fs/nfsd/state.h > @@ -573,6 +573,11 @@ enum nfsd4_cb_op { >   NFSPROC4_CLNT_CB_SEQUENCE, >  }; >   > +/* Returns true iff a is later than b: */ > +static inline bool nfsd4_stateid_generation_after(stateid_t *a, stateid_t *b) > +{ > + return (s32)(a->si_generation - b->si_generation) > 0; > +} >   >  struct nfsd4_compound_state; >  struct nfsd_net; -- Jeff Layton