From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f71.google.com (mail-pg0-f71.google.com [74.125.83.71]) by kanga.kvack.org (Postfix) with ESMTP id BE2376B0033 for ; Wed, 25 Oct 2017 11:23:33 -0400 (EDT) Received: by mail-pg0-f71.google.com with SMTP id s75so196159pgs.12 for ; Wed, 25 Oct 2017 08:23:33 -0700 (PDT) Received: from BJEXCAS004.didichuxing.com ([36.110.17.22]) by mx.google.com with ESMTPS id w16si1683476plp.130.2017.10.25.08.23.32 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 25 Oct 2017 08:23:32 -0700 (PDT) Date: Wed, 25 Oct 2017 23:23:18 +0800 From: weiping zhang Subject: [PATCH] bdi: add check before create debugfs dir or files Message-ID: <20171025152312.GA23944@source.didichuxing.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline Sender: owner-linux-mm@kvack.org List-ID: To: axboe@kernel.dk, jack@suse.cz Cc: linux-mm@kvack.org we should make sure parents directory exist, and then create dir or files under that. Signed-off-by: weiping zhang --- mm/backing-dev.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 74b52dfd5852..81f4a86ebbed 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -115,9 +115,11 @@ static const struct file_operations bdi_debug_stats_fops = { static void bdi_debug_register(struct backing_dev_info *bdi, const char *name) { - bdi->debug_dir = debugfs_create_dir(name, bdi_debug_root); - bdi->debug_stats = debugfs_create_file("stats", 0444, bdi->debug_dir, - bdi, &bdi_debug_stats_fops); + if (bdi_debug_root) + bdi->debug_dir = debugfs_create_dir(name, bdi_debug_root); + if (bdi->debug_dir) + bdi->debug_stats = debugfs_create_file("stats", 0444, + bdi->debug_dir, bdi, &bdi_debug_stats_fops); } static void bdi_debug_unregister(struct backing_dev_info *bdi) -- 2.14.2 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org