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From: Miklos Szeredi <miklos@szeredi.hu>
Date: Tue, 25 Sep 2018 10:48:37 +0200
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Subject: Re: [fuse-devel] [fuse] How to trigger writeback?
To: fuse-devel <fuse-devel@lists.sourceforge.net>,
        Miklos Szeredi <mszeredi@redhat.com>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>
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On Tue, Sep 25, 2018 at 10:30 AM, Nikolaus Rath <Nikolaus@rath.org> wrote:
> On Sep 24 2018, Miklos Szeredi <miklos@szeredi.hu> wrote:
>> On Mon, Sep 24, 2018 at 10:02 AM, Nikolaus Rath <Nikolaus@rath.org> wrote:
>>> Hi,
>>>
>>> How do I trigger writeback from a (writeback-cache enabled) FUSE
>>> filesystem?
>>
>> No way, currently (well, triggering fsync(2)/fdatasync(2) on the
>> filesystem would work, but such recursion is considered highly
>> hackish).
>
>
> You mean sync(2)/syncfs(2), not fsync(), right? Unless my manpages are
> out of date, fsync() only works on a specific inode.

I would've thought you only need writeback of a specific inode for reflink, no?

Thanks,
Miklos