[PATCH 11/25] mm: Convert mapping_get_entry to return a folio

["Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>]

The pagecache only contains folios, so this is the right thing to do.

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
 mm/filemap.c | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/mm/filemap.c b/mm/filemap.c
index 654bba53442a..b9f25a2d8312 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1673,33 +1673,33 @@ EXPORT_SYMBOL(page_cache_prev_miss);
  * @index: The page cache index.
  *
  * Looks up the page cache slot at @mapping & @offset.  If there is a
- * page cache page, the head page is returned with an increased refcount.
+ * page cache page, the folio is returned with an increased refcount.
  *
  * If the slot holds a shadow entry of a previously evicted page, or a
  * swap entry from shmem/tmpfs, it is returned.
  *
- * Return: The head page or shadow entry, %NULL if nothing is found.
+ * Return: The folio or shadow entry, %NULL if nothing is found.
  */
-static struct page *mapping_get_entry(struct address_space *mapping,
+static struct folio *mapping_get_entry(struct address_space *mapping,
 		pgoff_t index)
 {
 	XA_STATE(xas, &mapping->i_pages, index);
-	struct page *page;
+	struct folio *folio;
 
 	rcu_read_lock();
 repeat:
 	xas_reset(&xas);
-	page = xas_load(&xas);
-	if (xas_retry(&xas, page))
+	folio = xas_load(&xas);
+	if (xas_retry(&xas, folio))
 		goto repeat;
 	/*
 	 * A shadow entry of a recently evicted page, or a swap entry from
 	 * shmem/tmpfs.  Return it without attempting to raise page count.
 	 */
-	if (!page || xa_is_value(page))
+	if (!folio || xa_is_value(folio))
 		goto out;
 
-	if (!page_cache_get_speculative(page))
+	if (!page_cache_get_speculative(&folio->page))
 		goto repeat;
 
 	/*
@@ -1707,14 +1707,14 @@ static struct page *mapping_get_entry(struct address_space *mapping,
 	 * This is part of the lockless pagecache protocol. See
 	 * include/linux/pagemap.h for details.
 	 */
-	if (unlikely(page != xas_reload(&xas))) {
-		put_page(page);
+	if (unlikely(folio != xas_reload(&xas))) {
+		put_folio(folio);
 		goto repeat;
 	}
 out:
 	rcu_read_unlock();
 
-	return page;
+	return folio;
 }
 
 /**
@@ -1757,7 +1757,7 @@ struct page *pagecache_get_page(struct address_space *mapping, pgoff_t index,
 	struct page *page;
 
 repeat:
-	page = mapping_get_entry(mapping, index);
+	page = &mapping_get_entry(mapping, index)->page;
 	if (xa_is_value(page)) {
 		if (fgp_flags & FGP_ENTRY)
 			return page;
-- 
2.29.2