[08/16] nds32: flush_dcache_page: use page_mapping_file to avoid races with swapoff

Commit Message

Andrew Morton April 9, 2021, 8:27 p.m. UTC

From: Mike Rapoport <[e-mail]>
Subject: nds32: flush_dcache_page: use page_mapping_file to avoid races with swapoff

Commit cb9f753a3731 ("mm: fix races between swapoff and flush dcache")
updated flush_dcache_page implementations on several architectures to use
page_mapping_file() in order to avoid races between page_mapping() and
swapoff().

This update missed arch/nds32 and there is a possibility of a race there.

Replace page_mapping() with page_mapping_file() in nds32 implementation of
flush_dcache_page().

Link: https://lkml.kernel.org/r/[e-mail]
Fixes: cb9f753a3731 ("mm: fix races between swapoff and flush dcache")
Signed-off-by: Mike Rapoport <[e-mail]>
Reviewed-by: Matthew Wilcox (Oracle) <[e-mail]>
Acked-by: Greentime Hu <[e-mail]>
Cc: Huang Ying <[e-mail]>
Cc: Nick Hu <[e-mail]>
Cc: Vincent Chen <[e-mail]>
Cc: <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 arch/nds32/mm/cacheflush.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Patch

--- a/arch/nds32/mm/cacheflush.c~nds32-flush_dcache_page-use-page_mapping_file-to-avoid-races-with-swapoff
+++ a/arch/nds32/mm/cacheflush.c
@@ -238,7 +238,7 @@  void flush_dcache_page(struct page *page
 {
 	struct address_space *mapping;
 
-	mapping = page_mapping(page);
+	mapping = page_mapping_file(page);
 	if (mapping && !mapping_mapped(mapping))
 		set_bit(PG_dcache_dirty, &page->flags);
 	else {