Date: Thu, 06 Jul 2023 12:14:58 -0400
From: Jeff Layton <jlayton@...nel.org>
To: "Eric W. Biederman" <ebiederm@...ssion.com>
Cc: jk@...abs.org, arnd@...db.de, mpe@...erman.id.au, npiggin@...il.com, 
 christophe.leroy@...roup.eu, hca@...ux.ibm.com, gor@...ux.ibm.com, 
 agordeev@...ux.ibm.com, borntraeger@...ux.ibm.com, svens@...ux.ibm.com, 
 gregkh@...uxfoundation.org, arve@...roid.com, tkjos@...roid.com,
 maco@...roid.com,  joel@...lfernandes.org, brauner@...nel.org,
 cmllamas@...gle.com, surenb@...gle.com, 
 dennis.dalessandro@...nelisnetworks.com, jgg@...pe.ca, leon@...nel.org, 
 bwarrum@...ux.ibm.com, rituagar@...ux.ibm.com, ericvh@...nel.org,
 lucho@...kov.net,  asmadeus@...ewreck.org, linux_oss@...debyte.com,
 dsterba@...e.com,  dhowells@...hat.com, marc.dionne@...istor.com,
 viro@...iv.linux.org.uk,  raven@...maw.net, luisbg@...nel.org,
 salah.triki@...il.com,  aivazian.tigran@...il.com, keescook@...omium.org,
 clm@...com, josef@...icpanda.com,  xiubli@...hat.com, idryomov@...il.com,
 jaharkes@...cmu.edu, coda@...cmu.edu,  jlbec@...lplan.org, hch@....de,
 nico@...xnic.net, rafael@...nel.org,  code@...icks.com, ardb@...nel.org,
 xiang@...nel.org, chao@...nel.org,  huyue2@...lpad.com,
 jefflexu@...ux.alibaba.com, linkinjeon@...nel.org,  sj1557.seo@...sung.com,
 jack@...e.com, tytso@....edu, adilger.kernel@...ger.ca, 
 jaegeuk@...nel.org, hirofumi@...l.parknet.co.jp, miklos@...redi.hu, 
 rpeterso@...hat.com, agruenba@...hat.com, richard@....at, 
 anton.ivanov@...bridgegreys.com, johannes@...solutions.net, 
 mikulas@...ax.karlin.mff.cuni.cz, mike.kravetz@...cle.com,
 muchun.song@...ux.dev,  dwmw2@...radead.org, shaggy@...nel.org,
 tj@...nel.org,  trond.myklebust@...merspace.com, anna@...nel.org,
 chuck.lever@...cle.com,  neilb@...e.de, kolga@...app.com,
 Dai.Ngo@...cle.com, tom@...pey.com,  konishi.ryusuke@...il.com,
 anton@...era.com,  almaz.alexandrovich@...agon-software.com,
 mark@...heh.com,  joseph.qi@...ux.alibaba.com, me@...copeland.com,
 hubcap@...ibond.com,  martin@...ibond.com, amir73il@...il.com,
 mcgrof@...nel.org, yzaikin@...gle.com,  tony.luck@...el.com,
 gpiccoli@...lia.com, al@...rsen.net, sfrench@...ba.org,  pc@...guebit.com,
 lsahlber@...hat.com, sprasad@...rosoft.com,  senozhatsky@...omium.org,
 phillip@...ashfs.org.uk, rostedt@...dmis.org,  mhiramat@...nel.org,
 dushistov@...l.ru, hdegoede@...hat.com, djwong@...nel.org, 
 dlemoal@...nel.org, naohiro.aota@....com, jth@...nel.org, ast@...nel.org, 
 daniel@...earbox.net, andrii@...nel.org, martin.lau@...ux.dev,
 song@...nel.org,  yhs@...com, john.fastabend@...il.com, kpsingh@...nel.org,
 sdf@...gle.com,  haoluo@...gle.com, jolsa@...nel.org, hughd@...gle.com,
 akpm@...ux-foundation.org,  davem@...emloft.net, edumazet@...gle.com,
 kuba@...nel.org, pabeni@...hat.com,  john.johansen@...onical.com,
 paul@...l-moore.com, jmorris@...ei.org,  serge@...lyn.com,
 stephen.smalley.work@...il.com, eparis@...isplace.org,  jgross@...e.com,
 stern@...land.harvard.edu, lrh2000@....edu.cn, 
 sebastian.reichel@...labora.com, wsa+renesas@...g-engineering.com, 
 quic_ugoswami@...cinc.com, quic_linyyuan@...cinc.com, john@...ping.me.uk, 
 error27@...il.com, quic_uaggarwa@...cinc.com, hayama@...eo.co.jp,
 jomajm@...il.com,  axboe@...nel.dk, dhavale@...gle.com,
 dchinner@...hat.com, hannes@...xchg.org,  zhangpeng362@...wei.com,
 slava@...eyko.com, gargaditya08@...e.com, 
 penguin-kernel@...ove.SAKURA.ne.jp, yifeliu@...stonybrook.edu, 
 madkar@...stonybrook.edu, ezk@...stonybrook.edu, yuzhe@...china.com, 
 willy@...radead.org, okanatov@...il.com, jeffxu@...omium.org,
 linux@...blig.org,  mirimmad17@...il.com, yijiangshan@...inos.cn,
 yang.yang29@....com.cn,  xu.xin16@....com.cn, chengzhihao1@...wei.com,
 shr@...kernel.io,  Liam.Howlett@...cle.com, adobriyan@...il.com,
 chi.minghao@....com.cn,  roberto.sassu@...wei.com, linuszeng@...cent.com,
 bvanassche@....org,  zohar@...ux.ibm.com, yi.zhang@...wei.com,
 trix@...hat.com, fmdefrancesco@...il.com,  ebiggers@...gle.com,
 princekumarmaurya06@...il.com, chenzhongjin@...wei.com,  riel@...riel.com,
 shaozhengchao@...wei.com, jingyuwang_vip@....com, 
 linuxppc-dev@...ts.ozlabs.org, linux-kernel@...r.kernel.org, 
 linux-s390@...r.kernel.org, linux-rdma@...r.kernel.org, 
 linux-usb@...r.kernel.org, v9fs@...ts.linux.dev,
 linux-fsdevel@...r.kernel.org,  linux-afs@...ts.infradead.org,
 autofs@...r.kernel.org, linux-mm@...ck.org,  linux-btrfs@...r.kernel.org,
 ceph-devel@...r.kernel.org,  codalist@...a.cs.cmu.edu,
 ecryptfs@...r.kernel.org, linux-efi@...r.kernel.org, 
 linux-erofs@...ts.ozlabs.org, linux-ext4@...r.kernel.org, 
 linux-f2fs-devel@...ts.sourceforge.net, cluster-devel@...hat.com, 
 linux-um@...ts.infradead.org, linux-mtd@...ts.infradead.org, 
 jfs-discussion@...ts.sourceforge.net, linux-nfs@...r.kernel.org, 
 linux-nilfs@...r.kernel.org, linux-ntfs-dev@...ts.sourceforge.net, 
 ntfs3@...ts.linux.dev, ocfs2-devel@...ts.linux.dev, 
 linux-karma-devel@...ts.sourceforge.net, devel@...ts.orangefs.org, 
 linux-unionfs@...r.kernel.org, linux-hardening@...r.kernel.org, 
 reiserfs-devel@...r.kernel.org, linux-cifs@...r.kernel.org, 
 samba-technical@...ts.samba.org, linux-trace-kernel@...r.kernel.org, 
 linux-xfs@...r.kernel.org, bpf@...r.kernel.org, netdev@...r.kernel.org, 
 apparmor@...ts.ubuntu.com, linux-security-module@...r.kernel.org, 
 selinux@...r.kernel.org
Subject: Re: [PATCH v2 00/89] fs: new accessors for inode->i_ctime

On Thu, 2023-07-06 at 10:16 -0500, Eric W. Biederman wrote:
> Jeff Layton <jlayton@...nel.org> writes:
> 
> > On Wed, 2023-07-05 at 14:58 -0400, Jeff Layton wrote:
> > > v2:
> > > - prepend patches to add missing ctime updates
> > > - add simple_rename_timestamp helper function
> > > - rename ctime accessor functions as inode_get_ctime/inode_set_ctime_*
> > > - drop individual inode_ctime_set_{sec,nsec} helpers
> > > 
> > > I've been working on a patchset to change how the inode->i_ctime is
> > > accessed in order to give us conditional, high-res timestamps for the
> > > ctime and mtime. struct timespec64 has unused bits in it that we can use
> > > to implement this. In order to do that however, we need to wrap all
> > > accesses of inode->i_ctime to ensure that bits used as flags are
> > > appropriately handled.
> > > 
> > > The patchset starts with reposts of some missing ctime updates that I
> > > spotted in the tree. It then adds a new helper function for updating the
> > > timestamp after a successful rename, and new ctime accessor
> > > infrastructure.
> > > 
> > > The bulk of the patchset is individual conversions of different
> > > subsysteme to use the new infrastructure. Finally, the patchset renames
> > > the i_ctime field to __i_ctime to help ensure that I didn't miss
> > > anything.
> > > 
> > > This should apply cleanly to linux-next as of this morning.
> > > 
> > > Most of this conversion was done via 5 different coccinelle scripts, run
> > > in succession, with a large swath of by-hand conversions to clean up the
> > > remainder.
> > > 
> > 
> > A couple of other things I should note:
> > 
> > If you sent me an Acked-by or Reviewed-by in the previous set, then I
> > tried to keep it on the patch here, since the respun patches are mostly
> > just renaming stuff from v1. Let me know if I've missed any.
> > 
> > I've also pushed the pile to my tree as this tag:
> > 
> >     https://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux.git/tag/?h=ctime.20230705
> > 
> > In case that's easier to work with.
> 
> Are there any preliminary patches showing what you want your introduced
> accessors to turn into?  It is hard to judge the sanity of the
> introduction of wrappers without seeing what the wrappers are ultimately
> going to do.
> 
> Eric

I have a draft version of the multigrain patches on top of the wrapper
conversion I've already posted in my "mgctime-experimental" branch:

    https://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux.git/log/?h=mgctime-experimental

The rationale is best explained in this changelog:

    https://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux.git/commit/?h=mgctime-experimental&id=face437a144d3375afb7f70c233b0644b4edccba

The idea will be to enable this on a per-fs basis.
-- 
Jeff Layton <jlayton@...nel.org>

Powered by blists - more mailing lists