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Date:   Fri, 3 Nov 2023 07:23:39 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc:     Christian Brauner <brauner@kernel.org>,
        Christoph Hellwig <hch@infradead.org>,
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        Chris Mason <clm@fb.com>, David Sterba <dsterba@suse.com>,
        linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 0/3] fanotify support for btrfs sub-volumes
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On Wed, Nov 01, 2023 at 07:11:53PM +1030, Qu Wenruo wrote:
> > mount -t btrfs /dev/sda /mnt
> > 
> > could be exploded into 1000 individual mounts. Which many users might not want.
> 
> Can we make it dynamic? AKA, the btrfs_insert_fs_root() is the perfect
> timing here.
> 
> That would greatly reduce the initial vfsmount explode, but I'm not sure
> if it's possible to add vfsmount halfway.

Yes, that's what I had in mind as well.