fuse: set mapping error in writepage_locked when it fails

This ensures that we see errors on fsync when writeback fails.

Signed-off-by: Jeff Layton <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Signed-off-by: Miklos Szeredi <[email protected]>

fs/fuse/file.c

@@ -1669,6 +1669,7 @@ static int fuse_writepage_locked(struct page *page)
 err_free:
 	fuse_request_free(req);
 err:
+	mapping_set_error(page->mapping, error);
 	end_page_writeback(page);
 	return error;
 }