[PATCH 4/8] iov_iter: Convert iov_iter_extract_xarray_pages() to use folios

["Matthew Wilcox (Oracle)" <willy@infradead.org>]

ITER_XARRAY is exclusively used with xarrays that contain folios,
not pages, so extract folio pointers from it, not page pointers.
Removes a use of find_subpage().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 lib/iov_iter.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 7c50691fc5bb..a56bbf71a5d6 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -1650,11 +1650,11 @@ static ssize_t iov_iter_extract_xarray_pages(struct iov_iter *i,
 					     iov_iter_extraction_t extraction_flags,
 					     size_t *offset0)
 {
-	struct page *page, **p;
+	struct page **p;
+	struct folio *folio;
 	unsigned int nr = 0, offset;
 	loff_t pos = i->xarray_start + i->iov_offset;
-	pgoff_t index = pos >> PAGE_SHIFT;
-	XA_STATE(xas, i->xarray, index);
+	XA_STATE(xas, i->xarray, pos >> PAGE_SHIFT);
 
 	offset = pos & ~PAGE_MASK;
 	*offset0 = offset;
@@ -1665,17 +1665,17 @@ static ssize_t iov_iter_extract_xarray_pages(struct iov_iter *i,
 	p = *pages;
 
 	rcu_read_lock();
-	for (page = xas_load(&xas); page; page = xas_next(&xas)) {
-		if (xas_retry(&xas, page))
+	for (folio = xas_load(&xas); folio; folio = xas_next(&xas)) {
+		if (xas_retry(&xas, folio))
 			continue;
 
-		/* Has the page moved or been split? */
-		if (unlikely(page != xas_reload(&xas))) {
+		/* Has the folio moved or been split? */
+		if (unlikely(folio != xas_reload(&xas))) {
 			xas_reset(&xas);
 			continue;
 		}
 
-		p[nr++] = find_subpage(page, xas.xa_index);
+		p[nr++] = folio_file_page(folio, xas.xa_index);
 		if (nr == maxpages)
 			break;
 	}
-- 
2.47.2