disable large folios for shmem file used by xfs xfile

[Christoph Hellwig]

On Wed, Jan 10, 2024 at 07:38:43AM -0800, Andrew Morton wrote:
> I assume that kernels which contain 137db333b29186 ("xfs: teach xfile
> to pass back direct-map pages to caller") want this, so a Fixes: that
> and a cc:stable are appropriate?

I think it needs to back all the way back to 3934e8ebb7c
("xfs: create a big array data structure") as that only clears the page
sized chunk of a new allocation and could lead to corruption / or
information leaks.