Return-Path: linux-nfs-owner@vger.kernel.org Received: from fieldses.org ([174.143.236.118]:60765 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755535Ab3EUSwE (ORCPT ); Tue, 21 May 2013 14:52:04 -0400 Date: Tue, 21 May 2013 14:52:03 -0400 To: Steve Dickson Cc: Bruce Fields , Linux NFS Mailing list Subject: Re: [PATCH] NFSD: Don't give out read delegations on exclusive creates Message-ID: <20130521185203.GB12114@fieldses.org> References: <1368643909-8059-1-git-send-email-steved@redhat.com> <519BC044.8000808@RedHat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <519BC044.8000808@RedHat.com> From: "J. Bruce Fields" Sender: linux-nfs-owner@vger.kernel.org List-ID: On Tue, May 21, 2013 at 02:43:16PM -0400, Steve Dickson wrote: > Hey Bruce, > > Ping... ;-) I just pull from your for-3.11-incoming branch > and notice it was not there... Whoops, this had gotten buried in my inbox somehow. I'll take a look, thanks for the reminder. --b. > > This really does help with exclusive creates > not being delayed... So you might want to consider it... > > steved. > > On 15/05/13 14:51, Steve Dickson wrote: > > When an exclusive create is done with the mode bits > > set (aka open(testfile, O_CREAT | O_EXCL, 0777)) this > > causes a OPEN op followed by a SETATTR op. When a > > read delegation is given in the OPEN, it causes > > the SETATTR to delay with EAGAIN until the > > delegation is recalled. > > > > This patch caused exclusive creates to give out > > a write delegation (which turn into no delegation) > > which allows the SETATTR seamlessly succeed. > > > > Signed-off-by: Steve Dickson > > --- > > fs/nfsd/nfs4state.c | 12 ++++++++++-- > > 1 file changed, 10 insertions(+), 2 deletions(-) > > > > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > > index 316ec84..6b45d0e 100644 > > --- a/fs/nfsd/nfs4state.c > > +++ b/fs/nfsd/nfs4state.c > > @@ -3035,8 +3035,16 @@ nfs4_open_delegation(struct net *net, struct svc_fh *fh, > > goto out; > > if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE) > > flag = NFS4_OPEN_DELEGATE_WRITE; > > - else > > - flag = NFS4_OPEN_DELEGATE_READ; > > + else { > > + switch(open->op_createmode) { > > + case NFS4_CREATE_EXCLUSIVE: > > + case NFS4_CREATE_EXCLUSIVE4_1: > > + flag = NFS4_OPEN_DELEGATE_WRITE; > > + break; > > + default: > > + flag = NFS4_OPEN_DELEGATE_READ; > > + } > > + } > > break; > > default: > > goto out; > >