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	Mon, 15 Jan 2024 23:25:09 +0000
Date: Mon, 15 Jan 2024 23:25:09 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: Matthew Wilcox <willy@infradead.org>
Cc: Bruno Haible <bruno@clisp.org>, Evgeniy Dushistov <dushistov@mail.ru>,
	linux-fsdevel@vger.kernel.org
Subject: Re: ufs filesystem cannot mount NetBSD/arm64 partition
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On Mon, Jan 15, 2024 at 11:08:45PM +0000, Matthew Wilcox wrote:

> Wouldn't surprise me if netbsd/arm64 had decided to go with 64kB
> PAGE_SIZE and 8kB fragments ...
> 
> > FWIW, theoretically it might be possible to make that comparison with
> > PAGE_SIZE instead of 4096 and require 16K or 64K pages for the kernel
> > in question; that ought to work, modulo bugs in completely untested
> > cases ;-/
> > 
> > Support with 4K pages is a different story - that would take much
> > more surgery in fs/ufs.
> 
> Possibly not too much more.  With large folios, we're most of the way
> to being able to support this.  If there's real interest, we can look
> at supporting large folios in UFS.

Metadata handling will take some work.  I've done some untangling in
prep to that (see #work.ufs), but that's not all.  And fun around
tail unpacking is also not quite there.