Matthew Wilcox (Oracle) [off-list ref] wrote:

The pointers stored in the page cache are folios, by definition.
This change comes with a behaviour change -- callers of readahead_folio()
are no longer required to put the page reference themselves.  This matches
how readpage works, rather than matching how readpages used to work.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

For some of the things I'm looking at, this is actually inconvenient, but I
guess I can take an extra ref if I need it.

Reviewed-by: David Howells <dhowells@redhat.com>