mm/memcg: Convert mem_cgroup_track_foreign_dirty_slowpath() to folio

The page was only being used for the memcg and to gather trace
information, so this is a simple conversion.  The only caller of
mem_cgroup_track_foreign_dirty() will be converted to folios in a later
patch, so doing this now makes that patch simpler.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Howells <dhowells@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>

1 files changed, 4 insertions, 3 deletions

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 07eda24ec581..1c2776c3a223 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1599,17 +1599,18 @@ void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages,
 			 unsigned long *pheadroom, unsigned long *pdirty,
 			 unsigned long *pwriteback);
 
-void mem_cgroup_track_foreign_dirty_slowpath(struct page *page,
+void mem_cgroup_track_foreign_dirty_slowpath(struct folio *folio,
 					     struct bdi_writeback *wb);
 
 static inline void mem_cgroup_track_foreign_dirty(struct page *page,
 						  struct bdi_writeback *wb)
 {
+	struct folio *folio = page_folio(page);
 	if (mem_cgroup_disabled())
 		return;
 
-	if (unlikely(&page_memcg(page)->css != wb->memcg_css))
-		mem_cgroup_track_foreign_dirty_slowpath(page, wb);
+	if (unlikely(&folio_memcg(folio)->css != wb->memcg_css))
+		mem_cgroup_track_foreign_dirty_slowpath(folio, wb);
 }
 
 void mem_cgroup_flush_foreign(struct bdi_writeback *wb);