Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-qc0-f173.google.com ([209.85.216.173]:40248 "EHLO mail-qc0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752216Ab3I0BU1 (ORCPT ); Thu, 26 Sep 2013 21:20:27 -0400 Received: by mail-qc0-f173.google.com with SMTP id c3so1333192qcv.32 for ; Thu, 26 Sep 2013 18:20:26 -0700 (PDT) Message-ID: <5244DD58.8040506@primarydata.com> Date: Thu, 26 Sep 2013 21:20:24 -0400 From: Benny Halevy MIME-Version: 1.0 To: "J. Bruce Fields" CC: linux-nfs@vger.kernel.org Subject: Re: [PATCH RFC v0 04/49] pnfsd: don't set up back channel on create_session for ds References: <52447EA0.7070004@primarydata.com> <1380220807-12857-1-git-send-email-bhalevy@primarydata.com> <20130926220142.GC24894@pad.fieldses.org> In-Reply-To: <20130926220142.GC24894@pad.fieldses.org> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-nfs-owner@vger.kernel.org List-ID: On 2013-09-26 18:01, J. Bruce Fields wrote: > On Thu, Sep 26, 2013 at 02:40:07PM -0400, Benny Halevy wrote: >> From: Dean Hildebrand > > I don't understand why we need to do this. The motivation was that the DS doesn't need the backchannel as it will never issue any recalls or other callback ops. > > Also: based on the previous patch I believe we set the > EXCHGID4_FLAG_USE_PNFS_MDS bit in the reply unconditionally, so > regardless of what the client requests we're permitting it to use this > client as a MDS (or plain non-pnfs) server, so I'm not sure it matters > what the client requested. Hmm, True. > > Could you just drop this patch? Unless you have some good argument for > it. Yup. I see no problem in dropping it. Benny > > --b. > >> >> [was pnfsd: Add use of pnfs exchange flags] >> Signed-off-by: Dean Hildebrand >> [pnfsd: define a is_ds_only_session helper] >> Signed-off-by: Benny Halevy >> Signed-off-by: Benny Halevy >> --- >> fs/nfsd/nfs4state.c | 4 ++++ >> include/uapi/linux/nfs4.h | 7 +++++++ >> 2 files changed, 11 insertions(+) >> >> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c >> index 21c15fc..2c973e6 100644 >> --- a/fs/nfsd/nfs4state.c >> +++ b/fs/nfsd/nfs4state.c >> @@ -1953,6 +1953,10 @@ static __be32 nfsd4_check_cb_sec(struct nfsd4_cb_sec *cbs) >> status = nfserr_seq_misordered; >> goto out_free_conn; >> } >> + >> + if (is_ds_only_session(unconf->cl_exchange_flags)) >> + cr_ses->flags &= ~SESSION4_BACK_CHAN; >> + >> old = find_confirmed_client_by_name(&unconf->cl_name, nn); >> if (old) { >> status = mark_client_expired(old); >> diff --git a/include/uapi/linux/nfs4.h b/include/uapi/linux/nfs4.h >> index 788128e..028f5fc 100644 >> --- a/include/uapi/linux/nfs4.h >> +++ b/include/uapi/linux/nfs4.h >> @@ -125,6 +125,13 @@ >> #define EXCHGID4_FLAG_USE_PNFS_DS 0x00040000 >> #define EXCHGID4_FLAG_MASK_PNFS 0x00070000 >> >> +static inline bool >> +is_ds_only_session(u32 exchange_flags) >> +{ >> + u32 mask = EXCHGID4_FLAG_USE_PNFS_DS | EXCHGID4_FLAG_USE_PNFS_MDS; >> + return (exchange_flags & mask) == EXCHGID4_FLAG_USE_PNFS_DS; >> +} >> + >> #define EXCHGID4_FLAG_UPD_CONFIRMED_REC_A 0x40000000 >> #define EXCHGID4_FLAG_CONFIRMED_R 0x80000000 >> /* >> -- >> 1.8.3.1 >>