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 126D9C25B08 for ; Wed, 17 Aug 2022 13:48:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235623AbiHQNsC (ORCPT ); Wed, 17 Aug 2022 09:48:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38086 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230359AbiHQNsA (ORCPT ); Wed, 17 Aug 2022 09:48:00 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [IPv6:2001:67c:2178:6::1c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 27CDD95AE3; Wed, 17 Aug 2022 06:47:59 -0700 (PDT) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id D12B137C13; Wed, 17 Aug 2022 13:47:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1660744077; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=SKkfdBbjfHTzF/3ZAJcFbq9KFus9bcXKWd1NfKe/SGQ=; b=qidnjCb74Z/SnlqJqv5YiRHcAsQ/IUdtCY8WIhJdIKv3TAdG9H12iEkN9d3QOGBOm6WIl/ RS9plFrNqPPWLQJggEZY8h2zzGQxoGD/neaLb7OpOZXHcGHHtQl6NkfTxjxY1b4yVYKJOp xNAxWv4b2sdOQlpIaVH5DuUcLwaZ8UA= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1660744077; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=SKkfdBbjfHTzF/3ZAJcFbq9KFus9bcXKWd1NfKe/SGQ=; b=9XL8nbu2Eq4PuNLoFco8rt9GODKjsQYrRn15glMc8ZhCzOCPg1Q3dB0sW3GlyOvxz36JCm QCm+llEhtd2gSMCw== Received: from quack3.suse.cz (unknown [10.100.224.230]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id 909402C172; Wed, 17 Aug 2022 13:47:57 +0000 (UTC) Received: by quack3.suse.cz (Postfix, from userid 1000) id E15DBA066B; Wed, 17 Aug 2022 15:47:56 +0200 (CEST) Date: Wed, 17 Aug 2022 15:47:56 +0200 From: Jan Kara To: Jeff Layton Cc: Jan Kara , tytso@mit.edu, adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, Lukas Czerner , Christian Brauner Subject: Re: [PATCH] ext4: fix i_version handling in ext4 Message-ID: <20220817134756.bcr4qpno642mw6pd@quack3> References: <20220816131522.42467-1-jlayton@kernel.org> <20220817130441.qigqv62wj6lrvxfc@quack3> <20220817132533.4xvvkvltmwzudybm@quack3> <73ef7c1609d9045f7522111b53706ee65b1a253a.camel@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <73ef7c1609d9045f7522111b53706ee65b1a253a.camel@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Wed 17-08-22 09:28:52, Jeff Layton wrote: > On Wed, 2022-08-17 at 15:25 +0200, Jan Kara wrote: > > On Wed 17-08-22 09:09:58, Jeff Layton wrote: > > > On Wed, 2022-08-17 at 15:04 +0200, Jan Kara wrote: > > > > On Tue 16-08-22 09:15:22, 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 > > > > > > > > After some verification (which was not completely trivial e.g. for > > > > directories) I agree all cases should be covered. Feel free to add: > > > > > > > > Reviewed-by: Jan Kara > > > > > > > > Honza > > > > > > > > > > Thanks. > > > > > > I think this covers the typical cases, but there are some places I > > > missed: > > > > > > The setacl codepath, for one, and there are a number of places that set > > > the ctime explicitly for hole punching and the like. > > > > Hum, why is setacl() not covered by your change to ext4_xattr_set_handle()? > > ext4_set_acl() ends up calling it... I have checked hole punching (whole > > ext4_fallocate()) and it seems to be incrementing iversion where needed. > > > > Oh, ok! I mostly noticed the places I was "missing" by inspection. It's > possible that I don't need those changes after all. If you think this > patch is sufficient, then I'll plan to just go with this one. So I did some more grepping and I think we are missing i_version increment in ext4 ioctl handling. In particular stuff like swap_inode_boot_loader(), ext4_ioctl_setflags(), ext4_ioctl_setproject(), and EXT4_IOC_SETVERSION handling in __ext4_ioctl() need i_version increment. Similarly for defrag ioctl implemented in ext4_move_extents() (that even seems to miss a ctime update). Honza > > > > > --- > > > > > 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 > > > > > > > > > > > -- > > > Jeff Layton > > -- > Jeff Layton -- Jan Kara SUSE Labs, CR