Return-Path: Received: from mail-pd0-f172.google.com ([209.85.192.172]:33335 "EHLO mail-pd0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753892AbbFBBnI (ORCPT ); Mon, 1 Jun 2015 21:43:08 -0400 Received: by pdbqa5 with SMTP id qa5so120976723pdb.0 for ; Mon, 01 Jun 2015 18:43:08 -0700 (PDT) Message-ID: <556D0A27.4060802@gmail.com> Date: Tue, 02 Jun 2015 09:43:03 +0800 From: Kinglong Mee MIME-Version: 1.0 To: Steve Dickson , "linux-nfs@vger.kernel.org" CC: "J. Bruce Fields" , NeilBrown Subject: Re: [PATCH] exports: add allow_umount option for user un-mounting cached exports References: <5561EB38.5090105@gmail.com> In-Reply-To: <5561EB38.5090105@gmail.com> Content-Type: text/plain; charset=utf-8 Sender: linux-nfs-owner@vger.kernel.org List-ID: Please ignore this patch. Sorry for the noise. thanks, Kinglong Mee On 5/24/2015 11:16 PM, Kinglong Mee wrote: > After nfsd get exports cache, user cannot umounts the filesystem > which base on for a reference of the vfsmnt. > > This patch introduces a new option "allow_umount" for nfsd pining to > the vfsmnt, not get a refernce. At all, user can umount now. > > Signed-off-by: Kinglong Mee > --- > support/include/nfs/export.h | 3 ++- > support/nfs/exports.c | 6 ++++++ > utils/exportfs/exports.man | 8 ++++++++ > 3 files changed, 16 insertions(+), 1 deletion(-) > > diff --git a/support/include/nfs/export.h b/support/include/nfs/export.h > index 1194255..ca4e0c1 100644 > --- a/support/include/nfs/export.h > +++ b/support/include/nfs/export.h > @@ -26,7 +26,8 @@ > #define NFSEXP_CROSSMOUNT 0x4000 > #define NFSEXP_NOACL 0x8000 /* reserved for possible ACL related use */ > #define NFSEXP_V4ROOT 0x10000 > -#define NFSEXP_PNFS 0x20000 > +#define NFSEXP_PNFS 0x20000 > +#define NFSEXP_ALLOW_UMOUNT 0x40000 > /* > * All flags supported by the kernel before addition of the > * export_features interface: > diff --git a/support/nfs/exports.c b/support/nfs/exports.c > index 0aea6f1..ed5b984 100644 > --- a/support/nfs/exports.c > +++ b/support/nfs/exports.c > @@ -276,6 +276,8 @@ putexportent(struct exportent *ep) > if (ep->e_flags & NFSEXP_NOREADDIRPLUS) > fprintf(fp, "nordirplus,"); > fprintf(fp, "%spnfs,", (ep->e_flags & NFSEXP_PNFS)? "" : "no_"); > + if (ep->e_flags & NFSEXP_ALLOW_UMOUNT) > + fprintf(fp, "allow_umount,"); > if (ep->e_flags & NFSEXP_FSID) { > fprintf(fp, "fsid=%d,", ep->e_fsid); > } > @@ -586,6 +588,10 @@ parseopts(char *cp, struct exportent *ep, int warn, int *had_subtree_opt_ptr) > setflags(NFSEXP_PNFS, active, ep); > else if (!strcmp(opt, "no_pnfs")) > clearflags(NFSEXP_PNFS, active, ep); > + else if (!strcmp(opt, "allow_umount")) > + setflags(NFSEXP_ALLOW_UMOUNT, active, ep); > + else if (!strcmp(opt, "no_allow_umount")) > + clearflags(NFSEXP_ALLOW_UMOUNT, active, ep); > else if (strncmp(opt, "anonuid=", 8) == 0) { > char *oe; > ep->e_anonuid = strtol(opt+8, &oe, 10); > diff --git a/utils/exportfs/exports.man b/utils/exportfs/exports.man > index 9309246..d3947a4 100644 > --- a/utils/exportfs/exports.man > +++ b/utils/exportfs/exports.man > @@ -417,6 +417,14 @@ devices. The default can be explicitly requested with the > .I no_pnfs > option. > > +.TP > +.IR allow_umount > +This option allows user un-mounting the filesystem where cached nfsd exports > +is based on. Otherwise, the kernel may returns -EBUSY and un-mounting fail. > +The default is without the > +.I allow_umount > +option. > + > .SS User ID Mapping > .PP > .B nfsd >