mm/writeback: Add folio_account_cleaned()

Get the statistics right; compound pages were being accounted as a
single page.  This didn't matter before now as no filesystem which
supported compound pages did writeback.  Also move the declaration
to pagemap.h since this is part of the page cache.  Add a wrapper for
account_page_cleaned().

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, 7 insertions, 0 deletions

diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index aa9a083083df..8ba7da513ac4 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -778,6 +778,13 @@ static inline void __set_page_dirty(struct page *page,
 {
 	__folio_mark_dirty(page_folio(page), mapping, warn);
 }
+void folio_account_cleaned(struct folio *folio, struct address_space *mapping,
+			  struct bdi_writeback *wb);
+static inline void account_page_cleaned(struct page *page,
+		struct address_space *mapping, struct bdi_writeback *wb)
+{
+	return folio_account_cleaned(page_folio(page), mapping, wb);
+}
 
 int __set_page_dirty_nobuffers(struct page *page);
 int __set_page_dirty_no_writeback(struct page *page);