On Wed, Dec 08, 2021 at 04:22:52AM +0000, Matthew Wilcox (Oracle) wrote:

We still only operate on a single page of data at a time due to using
kmap().  A more complex implementation would work on each page in a folio,
but it's not clear that such a complex implementation would be worthwhile.

It sounds simple enough to be worthwhile.  But no need to do it here:

Reviewed-by: Christoph Hellwig <hch@lst.de>