From: Dave Chinner <david@fromorbit.com>
To: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: linux-fsdevel <linux-fsdevel@vger.kernel.org>,
xfs <linux-xfs@vger.kernel.org>,
linux-btrfs <linux-btrfs@vger.kernel.org>,
linux-ext4 <linux-ext4@vger.kernel.org>,
ocfs2 list <ocfs2-devel@oss.oracle.com>,
Christoph Hellwig <hch@infradead.org>,
Eric Sandeen <sandeen@redhat.com>, Theodore Ts'o <tytso@mit.edu>
Subject: [Ocfs2-devel] Broken O_{D,}SYNC behavior with FICLONE*?
Date: Fri, 4 Sep 2020 07:13:06 +1000 [thread overview]
Message-ID: <20200903211306.GE12131@dread.disaster.area> (raw)
In-Reply-To: <20200903035225.GJ6090@magnolia>
On Wed, Sep 02, 2020 at 08:52:25PM -0700, Darrick J. Wong wrote:
> Hi,
>
> I have a question for everyone-- do FICLONE and FICLONERANGE count as a
> "write operation" for the purposes of reasoning about O_SYNC and
> O_DSYNC?
I'd say yes, because we are changing metadata that is used to
directly reference the data in the file. O_DSYNC implies all the
metadata needed to access the data is on stable storage when the
operation returns....
> So, that's inconsistent behavior and I want to know if remap_file_range
> is broken or if we all just don't care about O_SYNC for these fancy
> IO accelerators?
Perhaps we should pay attention to the NFSD implementation of CloneFR -
if the operation is sync then it will run fsync on the destination
and commit_metadata on the source inode. See
nfsd4_clone_file_range().
So, yeah, I think clone operations need to pay attention to
O_DSYNC/O_SYNC/IS_SYNC()....
Cheers,
Dave.
--
Dave Chinner
david at fromorbit.com
prev parent reply other threads:[~2020-09-03 21:13 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-03 3:52 [Ocfs2-devel] Broken O_{D,}SYNC behavior with FICLONE*? Darrick J. Wong
2020-09-03 14:27 ` Christoph Hellwig
2020-09-03 21:13 ` Dave Chinner [this message]
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=20200903211306.GE12131@dread.disaster.area \
--to=david@fromorbit.com \
--cc=darrick.wong@oracle.com \
--cc=hch@infradead.org \
--cc=linux-btrfs@vger.kernel.org \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-xfs@vger.kernel.org \
--cc=ocfs2-devel@oss.oracle.com \
--cc=sandeen@redhat.com \
--cc=tytso@mit.edu \
/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).