From: Christian Brauner <brauner@kernel.org>
To: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@ZenIV.linux.org.uk>,
linux-fsdevel@vger.kernel.org, Miklos Szeredi <miklos@szeredi.hu>,
"Darrick J. Wong" <djwong@kernel.org>, Ted Tso <tytso@mit.edu>,
Jaegeuk Kim <jaegeuk@kernel.org>,
linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org,
linux-f2fs-devel@lists.sourceforge.net, stable@vger.kernel.org
Subject: Re: [PATCH v2 4/6] fs: Establish locking order for unrelated directories
Date: Thu, 1 Jun 2023 17:59:19 +0200 [thread overview]
Message-ID: <20230601-laube-golfball-c31fb218a534@brauner> (raw)
In-Reply-To: <20230601152449.h4ur5zrfqjqygujd@quack3>
On Thu, Jun 01, 2023 at 05:24:49PM +0200, Jan Kara wrote:
> On Thu 01-06-23 15:58:58, Christian Brauner wrote:
> > On Thu, Jun 01, 2023 at 12:58:24PM +0200, Jan Kara wrote:
> > > Currently the locking order of inode locks for directories that are not
> > > in ancestor relationship is not defined because all operations that
> > > needed to lock two directories like this were serialized by
> > > sb->s_vfs_rename_mutex. However some filesystems need to lock two
> > > subdirectories for RENAME_EXCHANGE operations and for this we need the
> > > locking order established even for two tree-unrelated directories.
> > > Provide a helper function lock_two_inodes() that establishes lock
> > > ordering for any two inodes and use it in lock_two_directories().
> > >
> > > CC: stable@vger.kernel.org
> > > Signed-off-by: Jan Kara <jack@suse.cz>
> > > ---
> > > fs/inode.c | 42 ++++++++++++++++++++++++++++++++++++++++++
> > > fs/internal.h | 2 ++
> > > fs/namei.c | 4 ++--
> > > 3 files changed, 46 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/fs/inode.c b/fs/inode.c
> > > index 577799b7855f..4000ab08bbc0 100644
> > > --- a/fs/inode.c
> > > +++ b/fs/inode.c
> > > @@ -1103,6 +1103,48 @@ void discard_new_inode(struct inode *inode)
> > > }
> > > EXPORT_SYMBOL(discard_new_inode);
> > >
> > > +/**
> > > + * lock_two_inodes - lock two inodes (may be regular files but also dirs)
> > > + *
> > > + * Lock any non-NULL argument. The caller must make sure that if he is passing
> > > + * in two directories, one is not ancestor of the other. Zero, one or two
> > > + * objects may be locked by this function.
> > > + *
> > > + * @inode1: first inode to lock
> > > + * @inode2: second inode to lock
> > > + * @subclass1: inode lock subclass for the first lock obtained
> > > + * @subclass2: inode lock subclass for the second lock obtained
> > > + */
> > > +void lock_two_inodes(struct inode *inode1, struct inode *inode2,
> > > + unsigned subclass1, unsigned subclass2)
> > > +{
> > > + if (!inode1 || !inode2)
> >
> > I think you forgot the opening bracket...
> > I can just fix this up for you though.
>
> Oh, yes. Apparently I forgot to rerun git-format-patch after fixing up this
> bit. I'm sorry for that. The patch series has survived full ext4 fstests
No problem at all!
next prev parent reply other threads:[~2023-06-01 15:59 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-01 10:58 [PATCH v2 0/6] fs: Fix directory corruption when moving directories Jan Kara
2023-06-01 10:58 ` [PATCH v2 1/6] ext4: Remove ext4 locking of moved directory Jan Kara
2023-06-01 14:52 ` Theodore Ts'o
2023-06-01 15:27 ` Jan Kara
2023-06-01 15:58 ` Christian Brauner
2023-06-01 10:58 ` [PATCH v2 2/6] Revert "udf: Protect rename against modification of moved directory" Jan Kara
2023-06-01 10:58 ` [PATCH v2 3/6] Revert "f2fs: fix potential corruption when moving a directory" Jan Kara
2023-06-01 10:58 ` [PATCH v2 4/6] fs: Establish locking order for unrelated directories Jan Kara
2023-06-01 13:58 ` Christian Brauner
2023-06-01 15:24 ` Jan Kara
2023-06-01 15:37 ` David Laight
2023-06-01 16:13 ` Jan Kara
2023-06-01 16:21 ` Christian Brauner
2023-06-01 16:33 ` David Laight
2023-06-02 12:34 ` Christian Brauner
2023-06-01 15:59 ` Christian Brauner [this message]
2023-06-02 1:36 ` kernel test robot
2023-06-01 10:58 ` [PATCH v2 5/6] fs: Lock moved directories Jan Kara
2023-06-01 10:58 ` [PATCH v2 6/6] fs: Restrict lock_two_nondirectories() to non-directory inodes Jan Kara
2023-06-02 13:05 ` [PATCH v2 0/6] fs: Fix directory corruption when moving directories Christian Brauner
2023-07-06 0:18 ` [f2fs-dev] " patchwork-bot+f2fs
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