From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8299DC2BB41 for ; Tue, 16 Aug 2022 13:33:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235761AbiHPNdw (ORCPT ); Tue, 16 Aug 2022 09:33:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53938 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235651AbiHPNdu (ORCPT ); Tue, 16 Aug 2022 09:33:50 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5B9593E77F; Tue, 16 Aug 2022 06:33:48 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 15F71B819FD; Tue, 16 Aug 2022 13:33:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D3064C433D6; Tue, 16 Aug 2022 13:33:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1660656825; bh=K7rgA97bYm7qFa7naN/9mIfuUpUlqcqW7RXJWAgCJAs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=SN93oLQcJLuyo6N5dB4naekgOzQ2oFkKyJn9OV8jpEtZdJm6GEU/CmeTV7zBeLg+V YwgtGhcaCxMv9camLjjZ1Qnoet23spYh1Z2MFiWr1OEHaBUGmSPrjA7pPJl+8P4bFq sA/S3AzxrPg7dEJx8zjcJeKkZjMpn0xYLZuzqWQb30Y3JY6tgeqJyQ1q7PdDnuMAO/ OrSyhCXXCQzpssQ56bFmPMuuJjZeNZ7QkoePpCTXMS5q731l0K+GPdEb6nw3hAlwpH v5s4aIqPNx3MQvkhhnJValCcluc9XOHm7ZuO80Pdyj6ORIz06DpzBHudVQC8ILrubZ 6+wTLB1JNBNrA== Date: Tue, 16 Aug 2022 15:33:40 +0200 From: Christian Brauner To: Jeff Layton Cc: tytso@mit.edu, adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, Lukas Czerner , Jan Kara Subject: Re: [PATCH] ext4: fix i_version handling in ext4 Message-ID: <20220816133340.mtaa7mxmgvhzffoh@wittgenstein> References: <20220816131522.42467-1-jlayton@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20220816131522.42467-1-jlayton@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Tue, Aug 16, 2022 at 09:15:22AM -0400, Jeff Layton wrote: > ext4 currently updates the i_version counter when the atime is updated > during a read. This is less than ideal as it can cause unnecessary cache > invalidations with NFSv4. The increment in ext4_mark_iloc_dirty is also > problematic since it can also corrupt the i_version counter for > ea_inodes. > > We aren't bumping the file times in ext4_mark_iloc_dirty, so changing > the i_version there seems wrong, and is the cause of both problems. > Remove that callsite and add increments to the setattr and setxattr > codepaths (at the same time that we update the ctime). The i_version > bump that already happens during timestamp updates should take care of > the rest. > > Cc: Lukas Czerner > Cc: Jan Kara > Cc: Christian Brauner > Signed-off-by: Jeff Layton > --- Seems good to me. But it seems that the xfs patch you sent does have inode_inc_version() right after setattr_copy() as well. So I wonder if we couldn't just try and move inode_inc_version() into setattr_copy() itself. > fs/ext4/inode.c | 10 +++++----- > fs/ext4/xattr.c | 2 ++ > 2 files changed, 7 insertions(+), 5 deletions(-) > > I think this patch should probably supersede Lukas' patch entitled: > > ext4: don't increase iversion counter for ea_inodes > > This will also mean that we'll need to respin the patch to turn on the > i_version counter unconditionally in ext4 (though that should be > trivial). > > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index 601214453c3a..a70921df89a5 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -5342,6 +5342,7 @@ int ext4_setattr(struct user_namespace *mnt_userns, struct dentry *dentry, > int error, rc = 0; > int orphan = 0; > const unsigned int ia_valid = attr->ia_valid; > + bool inc_ivers = IS_IVERSION(inode); > > if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) > return -EIO; > @@ -5425,8 +5426,8 @@ int ext4_setattr(struct user_namespace *mnt_userns, struct dentry *dentry, > return -EINVAL; > } > > - if (IS_I_VERSION(inode) && attr->ia_size != inode->i_size) > - inode_inc_iversion(inode); > + if (attr->ia_size == inode->i_size) > + inc_ivers = false; > > if (shrink) { > if (ext4_should_order_data(inode)) { > @@ -5528,6 +5529,8 @@ int ext4_setattr(struct user_namespace *mnt_userns, struct dentry *dentry, > } > > if (!error) { > + if (inc_ivers) > + inode_inc_iversion(inode); > setattr_copy(mnt_userns, inode, attr); > mark_inode_dirty(inode); > } > @@ -5731,9 +5734,6 @@ int ext4_mark_iloc_dirty(handle_t *handle, > } > ext4_fc_track_inode(handle, inode); > > - if (IS_I_VERSION(inode)) > - inode_inc_iversion(inode); > - > /* the do_update_inode consumes one bh->b_count */ > get_bh(iloc->bh); > > diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c > index 533216e80fa2..4d84919d1c9c 100644 > --- a/fs/ext4/xattr.c > +++ b/fs/ext4/xattr.c > @@ -2412,6 +2412,8 @@ ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, > if (!error) { > ext4_xattr_update_super_block(handle, inode->i_sb); > inode->i_ctime = current_time(inode); > + if (IS_IVERSION(inode)) > + inode_inc_iversion(inode); > if (!value) > no_expand = 0; > error = ext4_mark_iloc_dirty(handle, inode, &is.iloc); > -- > 2.37.2 >