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From: Miklos Szeredi <miklos@szeredi.hu>
Date: Mon, 24 Sep 2018 10:22:07 +0200
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Subject: Re: [fuse] What happens with dirty pages on NOTIFY_INVAL_INODE?
To: fuse-devel <fuse-devel@lists.sourceforge.net>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Miklos Szeredi <mszeredi@redhat.com>
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On Mon, Sep 24, 2018 at 10:06 AM, Nikolaus Rath <Nikolaus@rath.org> wrote:
> Hi,
>
> What happens with dirty pages when a (writeback-cache enabled) FUSE
> filesystem sends a NOTIFY_INVAL_INODE request? Are they dropped?
> flushed?

Haven't tried, but AFAICS it flushes dirty pages and waits on
writeback for these.  However, it doesn't wait on already queued
writes.  So it's a bit of a mess at the moment.

>
> To me neither behaviour seems correct...

What would be the correct operation be if neither flushing not
dropping them is correct?

Thanks,
Miklos