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Date:   Fri, 15 Sep 2023 22:51:12 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Luis Chamberlain <mcgrof@kernel.org>
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Subject: Re: [RFC v2 00/10] bdev: LBS devices support to coexist with
 buffer-heads
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On Fri, Sep 15, 2023 at 02:32:44PM -0700, Luis Chamberlain wrote:
> However, an issue is that disabling CONFIG_BUFFER_HEAD in practice is not viable
> for many Linux distributions since it also means disabling support for most
> filesystems other than btrfs and XFS. So we either support larger order folios
> on buffer-heads, or we draw up a solution to enable co-existence. Since at LSFMM
> 2023 it was decided we would not support larger order folios on buffer-heads,

Um, I didn't agree to that.  If block size is equal to folio size, there
are no problems supporting one buffer head per folio.  In fact, we could
probably go up to 8 buffer heads per folio without any trouble (but I'm
not signing up to do that work).