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 lists.sourceforge.net (lists.sourceforge.net [216.105.38.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E1E51EB64D8 for ; Wed, 21 Jun 2023 18:01:45 +0000 (UTC) Received: from [127.0.0.1] (helo=sfs-ml-3.v29.lw.sourceforge.com) by sfs-ml-3.v29.lw.sourceforge.com with esmtp (Exim 4.95) (envelope-from ) id 1qC29H-0003iv-Oc; Wed, 21 Jun 2023 18:01:44 +0000 Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-3.v29.lw.sourceforge.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1qC29G-0003ig-Bi; Wed, 21 Jun 2023 18:01:42 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=MIME-Version:Content-Transfer-Encoding:Content-Type :References:In-Reply-To:Date:To:From:Subject:Message-ID:Sender:Reply-To:Cc: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=ZG+t0WGX6sTaTgh3a79i3TULO64iDRYDnoN3E5sKu+s=; b=WeZLgkPyn9rFN7y+CCaU87nCGk qwKd2a2//IeBQoNCgwGIZm1yCv1xAtuU1WzOFzXQmFFNPOJ2f8yMPkutFaK6Js1uBy7RuOrR69yfM jOueIYn2pnVvp8f+n6es0vD7JeIrB1F3eJLi2pQq2jTINajqTQYjre91IO4zRSM0h86Y=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=MIME-Version:Content-Transfer-Encoding:Content-Type:References: In-Reply-To:Date:To:From:Subject:Message-ID:Sender:Reply-To:Cc:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=ZG+t0WGX6sTaTgh3a79i3TULO64iDRYDnoN3E5sKu+s=; b=X0ht3LwbU28i7PRcPv0KNJO9Pi ZarHz3/6vZZVp/8sSo6fVLAxUBTvDEoSP5mqNfTm/KScxTgwvhw9a5wEd7/zBf+MihAtGyKnN/sVt KasnIN76tf55TzaUauk6bRLE9/MIhuVrJcVwSb4Uy8raZnD+vUuhE+QN2G2t45P7y3Zw=; Received: from dfw.source.kernel.org ([139.178.84.217]) by sfi-mx-2.v28.lw.sourceforge.com with esmtps (TLS1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.95) id 1qC29F-0002zP-SD; Wed, 21 Jun 2023 18:01:42 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id F2317614C7; Wed, 21 Jun 2023 18:01:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 994ABC433C8; Wed, 21 Jun 2023 18:01:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1687370487; bh=f6MfE+OwYlooIGk6bzrRy2nMoaF6fYVrxR9rt/b+wHA=; h=Subject:From:To:Date:In-Reply-To:References:From; b=bVcrCvUx5qUKiFKoGoCpRU9cOdPpOKYso9mJvg46pEjfpa5HrNdfQIs+z6jHr5sux dlx89O00OX+JFXaZsV1aqCsQCXMgGUPun8gG0+O63APDuieKF+NHNtURapcBRt6lwA XUSZY7Lxndjjm0Guu7ABZsDoRASFWxW9NDkbTecnzII3k7EzTCDZqTBAfGwPJVYC9o 4y1h+nwRvjsJy2OJKNcBHeZcxgyGTH5ATcgrCrgxjm4t9FpTdCYfY2dSxFdgqaYmjq McRt37g4zUkhYaqSUzhLnP9BOtEXfLTVHkZOUz8jt6fW2f8bh/uJnCW9nUVVVNS/3d grPvoD0B9Xewg== Message-ID: <6f4bcd7d79f688120d80e96e86d7c521854d8e84.camel@kernel.org> From: Jeff Layton To: Tom Talpey , Jeremy Kerr , Arnd Bergmann , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Greg Kroah-Hartman , Arve =?ISO-8859-1?Q?Hj=F8nnev=E5g?= , Todd Kjos , Martijn Coenen , Joel Fernandes , Christian Brauner , Carlos Llamas , Suren Baghdasaryan , Dennis Dalessandro , Jason Gunthorpe , Leon Romanovsky , Brad Warrum , Ritu Agarwal , Eric Van Hensbergen , Latchesar Ionkov , Dominique Martinet , Christian Schoenebeck , David Sterba , David Howells , Marc Dionne , Alexander Viro , Ian Kent , Luis de Bethencourt , Salah Triki , "Tigran A. 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De Francesco" , Chen Zhongjin , Zhengchao Shao , Rik van Riel , Jingyu Wang , Hangyu Hua , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-rdma@vger.kernel.org, linux-usb@vger.kernel.org, v9fs@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-afs@lists.infradead.org, autofs@vger.kernel.org, linux-mm@kvack.org, linux-btrfs@vger.kernel.org, ceph-devel@vger.kernel.org, codalist@coda.cs.cmu.edu, ecryptfs@vger.kernel.org, linux-efi@vger.kernel.org, linux-erofs@lists.ozlabs.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, cluster-devel@redhat.com, linux-um@lists.infradead.org, linux-mtd@lists.infradead.org, jfs-discussion@lists.sourceforge.net, linux-nfs@vger.kernel.org, linux-nilfs@vger.kernel.org, linux-ntfs-dev@lists.sourceforge.net, ntfs3@lists.linux.dev, ocfs2-devel@oss.oracle.com, linux-karma-devel@lists.sourceforge.net, devel@lists.orangefs.org, linux-unionfs@vger.kernel.org, linux-hardening@vger.kernel.org, reiserfs-devel@vger.kernel.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-trace-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, bpf@vger.kernel.org, netdev@vger.kernel.org, apparmor@lists.ubuntu.com, linux-security-module@vger.kernel.org, selinux@vger.kernel.org Date: Wed, 21 Jun 2023 14:01:09 -0400 In-Reply-To: <1f97d595-e035-46ce-6269-eebfe922cf35@talpey.com> References: <20230621144507.55591-1-jlayton@kernel.org> <20230621144507.55591-2-jlayton@kernel.org> <1f97d595-e035-46ce-6269-eebfe922cf35@talpey.com> User-Agent: Evolution 3.48.3 (3.48.3-1.fc38) MIME-Version: 1.0 X-Headers-End: 1qC29F-0002zP-SD Subject: Re: [f2fs-dev] [PATCH 01/79] fs: add ctime accessors infrastructure X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net On Wed, 2023-06-21 at 13:29 -0400, Tom Talpey wrote: > On 6/21/2023 10:45 AM, Jeff Layton wrote: > > struct timespec64 has unused bits in the tv_nsec field that can be used > > for other purposes. In future patches, we're going to change how the > > inode->i_ctime is accessed in certain inodes in order to make use of > > them. In order to do that safely though, we'll need to eradicate raw > > accesses of the inode->i_ctime field from the kernel. > > > > Add new accessor functions for the ctime that we can use to replace them. > > > > Signed-off-by: Jeff Layton > > --- > > fs/inode.c | 16 ++++++++++++++ > > include/linux/fs.h | 53 +++++++++++++++++++++++++++++++++++++++++++++- > > 2 files changed, 68 insertions(+), 1 deletion(-) > > > > diff --git a/fs/inode.c b/fs/inode.c > > index d37fad91c8da..c005e7328fbb 100644 > > --- a/fs/inode.c > > +++ b/fs/inode.c > > @@ -2499,6 +2499,22 @@ struct timespec64 current_time(struct inode *inode) > > } > > EXPORT_SYMBOL(current_time); > > > > +/** > > + * inode_ctime_set_current - set the ctime to current_time > > + * @inode: inode > > + * > > + * Set the inode->i_ctime to the current value for the inode. Returns > > + * the current value that was assigned to i_ctime. > > + */ > > +struct timespec64 inode_ctime_set_current(struct inode *inode) > > +{ > > + struct timespec64 now = current_time(inode); > > + > > + inode_set_ctime(inode, now); > > + return now; > > +} > > +EXPORT_SYMBOL(inode_ctime_set_current); > > + > > /** > > * in_group_or_capable - check whether caller is CAP_FSETID privileged > > * @idmap: idmap of the mount @inode was found from > > diff --git a/include/linux/fs.h b/include/linux/fs.h > > index 6867512907d6..9afb30606373 100644 > > --- a/include/linux/fs.h > > +++ b/include/linux/fs.h > > @@ -1474,7 +1474,58 @@ static inline bool fsuidgid_has_mapping(struct super_block *sb, > > kgid_has_mapping(fs_userns, kgid); > > } > > > > -extern struct timespec64 current_time(struct inode *inode); > > +struct timespec64 current_time(struct inode *inode); > > +struct timespec64 inode_ctime_set_current(struct inode *inode); > > + > > +/** > > + * inode_ctime_peek - fetch the current ctime from the inode > > + * @inode: inode from which to fetch ctime > > + * > > + * Grab the current ctime from the inode and return it. > > + */ > > +static inline struct timespec64 inode_ctime_peek(const struct inode *inode) > > +{ > > + return inode->i_ctime; > > +} > > + > > +/** > > + * inode_ctime_set - set the ctime in the inode to the given value > > + * @inode: inode in which to set the ctime > > + * @ts: timespec value to set the ctime > > + * > > + * Set the ctime in @inode to @ts. > > + */ > > +static inline struct timespec64 inode_ctime_set(struct inode *inode, struct timespec64 ts) > > +{ > > + inode->i_ctime = ts; > > + return ts; > > +} > > + > > +/** > > + * inode_ctime_set_sec - set only the tv_sec field in the inode ctime > > I'm curious about why you choose to split the tv_sec and tv_nsec > set_ functions. Do any callers not set them both? Wouldn't a > single call enable a more atomic behavior someday? > > inode_ctime_set_sec_nsec(struct inode *, time64_t, time64_t) > > (or simply initialize a timespec64 and use inode_ctime_spec() ) > Yes, quite a few places set the fields individually. For example, when loading a value from disk that doesn't have sufficient granularity to set the nsecs field to anything but 0. Could I have done it by declaring a local timespec64 variable and just use the inode_ctime_set function in these places? Absolutely. That's a bit more difficult to handle with coccinelle though. If someone wants to suggest a way to do that without having to change all of these call sites manually, then I'm open to redoing the set. That might be better left for a later cleanup though. > > + * @inode: inode in which to set the ctime > > + * @sec: value to set the tv_sec field > > + * > > + * Set the sec field in the ctime. Returns @sec. > > + */ > > +static inline time64_t inode_ctime_set_sec(struct inode *inode, time64_t sec) > > +{ > > + inode->i_ctime.tv_sec = sec; > > + return sec; > > +} > > + > > +/** > > + * inode_ctime_set_nsec - set only the tv_nsec field in the inode ctime > > + * @inode: inode in which to set the ctime > > + * @nsec: value to set the tv_nsec field > > + * > > + * Set the nsec field in the ctime. Returns @nsec. > > + */ > > +static inline long inode_ctime_set_nsec(struct inode *inode, long nsec) > > +{ > > + inode->i_ctime.tv_nsec = nsec; > > + return nsec; > > +} > > > > /* > > * Snapshotting support. -- Jeff Layton _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel