From: Matthew Wilcox (Oracle) <willy@infradead.org>
Date: Wed, 2 Apr 2025 21:06:05 +0000 (+0100)
Subject: iov_iter: convert iter_xarray_populate_pages() to use folios
X-Git-Tag: v6.16-rc1~92^2~270
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b57f4f4f186d728a1b484be1f214f17d843b6a24;p=thirdparty%2Fkernel%2Flinux.git

iov_iter: convert iter_xarray_populate_pages() to use folios

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

Link: https://lkml.kernel.org/r/20250402210612.2444135-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index bc9391e55d57e..3e340d1fcadcf 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -1059,22 +1059,22 @@ static ssize_t iter_xarray_populate_pages(struct page **pages, struct xarray *xa
 					  pgoff_t index, unsigned int nr_pages)
 {
 	XA_STATE(xas, xa, index);
-	struct page *page;
+	struct folio *folio;
 	unsigned int ret = 0;
 
 	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;
 		}
 
-		pages[ret] = find_subpage(page, xas.xa_index);
-		get_page(pages[ret]);
+		pages[ret] = folio_file_page(folio, xas.xa_index);
+		folio_get(folio);
 		if (++ret == nr_pages)
 			break;
 	}