iov_iter: Add copy_folio_from_iter_atomic()

Add a folio wrapper around copy_page_from_iter_atomic().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>

lib/iov_iter.c

@@ -566,7 +566,7 @@ size_t iov_iter_zero(size_t bytes, struct iov_iter *i)
 }
 EXPORT_SYMBOL(iov_iter_zero);
 
-size_t copy_page_from_iter_atomic(struct page *page, unsigned offset,
+size_t copy_page_from_iter_atomic(struct page *page, size_t offset,
 		size_t bytes, struct iov_iter *i)
 {
 	size_t n, copied = 0;