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Date:   Thu, 15 Oct 2020 04:25:01 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Chengguang Xu <cgxu519@mykernel.net>
Cc:     miklos@szeredi.hu, amir73il@gmail.com, jack@suse.cz,
        linux-unionfs@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [RFC PATCH 1/5] fs: introduce notifier list for vfs inode
Message-ID: <20201015032501.GO3576660@ZenIV.linux.org.uk>
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 <20201010142355.741645-2-cgxu519@mykernel.net>
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On Sat, Oct 10, 2020 at 10:23:51PM +0800, Chengguang Xu wrote:
> Currently there is no notification api for kernel about modification
> of vfs inode, in some use cases like overlayfs, this kind of notification
> will be very helpful to implement containerized syncfs functionality.
> As the first attempt, we introduce marking inode dirty notification so that
> overlay's inode could mark itself dirty as well and then only sync dirty
> overlay inode while syncfs.

Who's responsible for removing the crap from notifier chain?  And how does
that affect the lifetime of inode?