From: David Sterba <dsterba@suse.cz>
To: Qu Wenruo <wqu@suse.com>
Cc: Cheng Yongkang <teel4res@gmail.com>,
David Sterba <dsterba@suse.com>, Chris Mason <mason@kernel.org>,
linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org,
stable@vger.kernel.org
Subject: Re: [PATCH v2] btrfs: reject refs=0 subvolume without DEAD in SUBVOL_SYNC_WAIT
Date: Mon, 9 Nov 2026 19:47:12 +0100 [thread overview]
Message-ID: <20261109184712.GF4186782@twin.jikos.cz> (raw)
In-Reply-To: <b4962b1b-bc5e-4302-8456-73b9b8a6474b@suse.com>
On Sun, Nov 01, 2026 at 05:48:21PM +1030, Qu Wenruo wrote:
> With that said, there are more problems with the ioctl.
>
> - No real user
> No one is utilizing BTRFS_SUBVOL_SYNC* flags. Btrfs-progs itself
> doesn't even bother it.
>
> So all these fixes are very low priority, unless there are some wild
> programs utilizing this.
>
> But even btrfs-progs doesn't utilize them, the possibility are very
> low.
Obviously the ioctl was added so progs 'subvol sync' can use it for
non-root users. I started working on it but there's a problem with the
behaviour change between the user types. Root has full access and
reports the progress while with this ioctl there were some problems I
don't remember. The ioctl was designed to emulate all modes that root
can do so it should be possible to get 1:1 output.
next prev parent reply other threads:[~2026-11-09 18:47 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-11-01 6:25 Cheng Yongkang
2026-11-01 6:51 ` Qu Wenruo
2026-11-01 7:18 ` Qu Wenruo
2026-11-01 7:33 ` Cheng Yongkang
2026-11-01 8:27 ` Qu Wenruo
2026-11-09 18:47 ` David Sterba [this message]
2026-11-09 20:30 ` Qu Wenruo
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=20261109184712.GF4186782@twin.jikos.cz \
--to=dsterba@suse.cz \
--cc=dsterba@suse.com \
--cc=linux-btrfs@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mason@kernel.org \
--cc=stable@vger.kernel.org \
--cc=teel4res@gmail.com \
--cc=wqu@suse.com \
/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
all inboxes | Powered by JetHome®