From patchwork Mon Aug 31 10:13:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Hao" X-Patchwork-Id: 11746029 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C31A51667 for ; Mon, 31 Aug 2020 10:13:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B5D882083E for ; Mon, 31 Aug 2020 10:13:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726100AbgHaKNU (ORCPT ); Mon, 31 Aug 2020 06:13:20 -0400 Received: from mail.cn.fujitsu.com ([183.91.158.132]:6214 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726081AbgHaKNU (ORCPT ); Mon, 31 Aug 2020 06:13:20 -0400 X-IronPort-AV: E=Sophos;i="5.76,375,1592841600"; d="scan'208";a="98733246" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 31 Aug 2020 18:13:15 +0800 Received: from G08CNEXMBPEKD04.g08.fujitsu.local (unknown [10.167.33.201]) by cn.fujitsu.com (Postfix) with ESMTP id 3772C48990D9; Mon, 31 Aug 2020 18:13:14 +0800 (CST) Received: from G08CNEXCHPEKD06.g08.fujitsu.local (10.167.33.205) by G08CNEXMBPEKD04.g08.fujitsu.local (10.167.33.201) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Mon, 31 Aug 2020 18:13:18 +0800 Received: from localhost.localdomain (10.167.225.206) by G08CNEXCHPEKD06.g08.fujitsu.local (10.167.33.209) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Mon, 31 Aug 2020 18:13:17 +0800 From: Hao Li To: CC: , , , , , , Subject: [PATCH] fs: Handle I_DONTCACHE in iput_final() instead of generic_drop_inode() Date: Mon, 31 Aug 2020 18:13:13 +0800 Message-ID: <20200831101313.168889-1-lihao2018.fnst@cn.fujitsu.com> X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 X-yoursite-MailScanner-ID: 3772C48990D9.AE7C8 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: lihao2018.fnst@cn.fujitsu.com X-Spam-Status: No Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org If generic_drop_inode() returns true, it means iput_final() can evict this inode regardless of whether it is dirty or not. If we check I_DONTCACHE in generic_drop_inode(), any inode with this bit set will be evicted unconditionally. This is not the desired behavior because I_DONTCACHE only means the inode shouldn't be cached on the LRU list. As for whether we need to evict this inode, this is what generic_drop_inode() should do. This patch corrects the usage of I_DONTCACHE. This patch was proposed in [1]. [1]: https://lore.kernel.org/linux-fsdevel/20200831003407.GE12096@dread.disaster.area/ Signed-off-by: Hao Li Reviewed-by: Ira Weiny --- fs/inode.c | 3 ++- include/linux/fs.h | 3 +-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/inode.c b/fs/inode.c index 72c4c347afb7..4e45d5ea3d0f 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -1625,7 +1625,8 @@ static void iput_final(struct inode *inode) else drop = generic_drop_inode(inode); - if (!drop && (sb->s_flags & SB_ACTIVE)) { + if (!drop && !(inode->i_state & I_DONTCACHE) && + (sb->s_flags & SB_ACTIVE)) { inode_add_lru(inode); spin_unlock(&inode->i_lock); return; diff --git a/include/linux/fs.h b/include/linux/fs.h index e019ea2f1347..93caee80ce47 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2922,8 +2922,7 @@ extern int inode_needs_sync(struct inode *inode); extern int generic_delete_inode(struct inode *inode); static inline int generic_drop_inode(struct inode *inode) { - return !inode->i_nlink || inode_unhashed(inode) || - (inode->i_state & I_DONTCACHE); + return !inode->i_nlink || inode_unhashed(inode); } extern void d_mark_dontcache(struct inode *inode);