linux-nfs.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Frank Filz" <ffilzlnx@mindspring.com>
To: "'NeilBrown'" <neilb@suse.de>,
	"'J. Bruce Fields'" <bfields@fieldses.org>
Cc: "'Chuck Lever'" <chuck.lever@oracle.com>,
	<linux-nfs@vger.kernel.org>,
	"'Josef Bacik'" <josef@toxicpanda.com>
Subject: RE: [PATCH v2] BTRFS/NFSD: provide more unique inode number for btrfs export
Date: Fri, 27 Aug 2021 07:53:11 -0700	[thread overview]
Message-ID: <002901d79b53$41ddba40$c5992ec0$@mindspring.com> (raw)
In-Reply-To: <163001583884.7591.13328510041463261313@noble.neil.brown.name>

> On Fri, 27 Aug 2021, J.  Bruce Fields wrote:
> > On Thu, Aug 26, 2021 at 04:03:04PM +1000, NeilBrown wrote:
> > >
> > > [[ Hi Bruce and Chuck,
> > >    I've rebased this patch on the earlier patch I sent which allows
> > >    me to use the name "fh_flags".  I've also added a missing #include.
> > >    I've added the 'Acked-by' which Joesf provided earlier for the
> > >    btrfs-part.  I don't have an 'ack' for the  stat.h part, but no-one
> > >    has complained wither.
> > >    I think it is as ready as it can be, and am keen to know what you
> > >    think.
> > >    I'm not *very* keen on testing s_magic in nfsd code (though we
> > >    already have a couple of such tests in nfs3proc.c), but it does have
> > >    the advantage of ensuring that no other filesystem can use this
> > >    functionality without landing a patch in fs/nfsd/.
> > >
> > >    Thanks for any review that you can provide,
> > >    NeilBrown
> > > ]]
> >
> > This seems hairy, but *somebody* has hated every single solution
> > proposed, so, argh, I don't know, maybe it's best.
> 
> People don't like change I guess :-)
> I think we need the fh_flags stuff for almost any fix, else existing mounts could
> break when the server is upgraded.  This could be needed for any filesystem that
> has flawed NFS export support and needs to seemlessly repair it.
> We *might* be able to avoid that is I xored the uniquifier with the fsid instead of
> the fileid (I'd have to test), but that has other problems like polluting the client's
> mount table and mounted-on-fileid being hard to manage - especially for NFSv3.
> The rest is the minimum that actually achieves something.

Changing the fsid for sub-volumes is Ganesha's solution (before adding that, we couldn't even export the sub-volumes at all).

Mangling the fileid is definitely the best solution if there will be lots of sub-volumes. For a few sub-volumes changing fsid does create additional mount points on the client with some issues, but does guarantee there will be no fileid collision.

My gut feel is your solution is the best one and Ganesha may need to switch to that solution.

Frank


  reply	other threads:[~2021-08-27 14:58 UTC|newest]

Thread overview: 51+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-26  4:28 [PATCH] NFSD: drop support for ancient file-handles NeilBrown
2021-08-26  6:03 ` [PATCH v2] BTRFS/NFSD: provide more unique inode number for btrfs export NeilBrown
2021-08-26 20:19   ` J.  Bruce Fields
2021-08-26 22:10     ` NeilBrown
2021-08-27 14:53       ` Frank Filz [this message]
2021-08-27 22:57         ` NeilBrown
2021-08-27 23:46           ` Frank Filz
2021-08-27 23:55             ` NeilBrown
2021-08-28  2:21               ` Frank Filz
2021-08-27 18:32       ` J.  Bruce Fields
2021-08-27 23:01         ` NeilBrown
2021-08-27 16:20   ` Christoph Hellwig
2021-08-27 23:05     ` NeilBrown
2021-08-28  7:09       ` Christoph Hellwig
2021-08-31  4:59         ` NeilBrown
2021-09-01  7:20           ` Christoph Hellwig
2021-09-01 15:22             ` J. Bruce Fields
2021-09-02  4:14               ` NeilBrown
2021-09-05 16:07                 ` J. Bruce Fields
2021-09-06  1:29                   ` NeilBrown
2021-09-11 14:12                     ` Amir Goldstein
2021-09-13  0:43                       ` NeilBrown
2021-09-13 10:04                         ` Amir Goldstein
2021-09-13 22:59                           ` NeilBrown
2021-09-14  5:45                             ` Amir Goldstein
2021-09-20 22:09                               ` NeilBrown
2021-09-02  7:11               ` Christoph Hellwig
2021-09-02  4:06             ` NeilBrown
2021-09-02  7:16               ` Christoph Hellwig
2021-09-02  7:53                 ` Miklos Szeredi
2021-09-02 14:16                   ` Frank Filz
2021-09-02 23:02                     ` NeilBrown
2021-08-26 14:10 ` [PATCH] NFSD: drop support for ancient file-handles Chuck Lever III
2021-08-26 21:38   ` NeilBrown
2021-08-26 14:51 ` J.  Bruce Fields
2021-08-26 21:41   ` NeilBrown
2021-08-27 15:15 ` Christoph Hellwig
2021-08-27 23:24   ` NeilBrown
2021-08-31  4:41   ` [PATCH 1/2 v2] NFSD: drop support for ancient filehandles NeilBrown
2021-08-31  4:42     ` [PATCH 2/2] NFSD: simplify struct nfsfh NeilBrown
2021-09-01  7:44       ` Christoph Hellwig
2021-09-01  7:44     ` [PATCH 1/2 v2] NFSD: drop support for ancient filehandles Christoph Hellwig
2021-09-01 14:21       ` Chuck Lever III
2021-09-02  1:14         ` [PATCH 1/3 v3] NFSD: move filehandle format declarations out of "uapi" NeilBrown
2021-09-02  1:15           ` [PATCH 2/3 v3] NFSD: drop support for ancient filehandles NeilBrown
2021-09-02  1:16             ` [PATCH 3/3 v3] NFSD: simplify struct nfsfh NeilBrown
2021-09-02  7:22             ` [PATCH 2/3 v3] NFSD: drop support for ancient filehandles Christoph Hellwig
2021-09-02  7:21           ` [PATCH 1/3 v3] NFSD: move filehandle format declarations out of "uapi" Christoph Hellwig
2021-09-23 21:21           ` Bruce Fields
2021-09-25  4:21             ` NeilBrown
  -- strict thread matches above, loose matches on Subject: below --
2021-07-27 22:37 [PATCH/RFC 00/11] expose btrfs subvols in mount table correctly NeilBrown
2021-08-13  1:45 ` [PATCH] VFS/BTRFS/NFSD: provide more unique inode number for btrfs export NeilBrown
2021-08-15  7:39   ` Goffredo Baroncelli
2021-08-15 19:35     ` Roman Mamedov
2021-08-15 22:17       ` NeilBrown
2021-08-23  4:05         ` [PATCH v2] BTRFS/NFSD: " NeilBrown

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='002901d79b53$41ddba40$c5992ec0$@mindspring.com' \
    --to=ffilzlnx@mindspring.com \
    --cc=bfields@fieldses.org \
    --cc=chuck.lever@oracle.com \
    --cc=josef@toxicpanda.com \
    --cc=linux-nfs@vger.kernel.org \
    --cc=neilb@suse.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).