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	Mon, 09 Jun 2025 05:34:42 +0000
Date: Mon, 9 Jun 2025 06:34:42 +0100
From: Al Viro <viro@zeniv.linux.org.uk>
To: NeilBrown <neil@brown.name>
Cc: Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>,
	Chuck Lever <chuck.lever@oracle.com>,
	Jeff Layton <jlayton@kernel.org>,
	Amir Goldstein <amir73il@gmail.com>,
	Jan Harkes <jaharkes@cs.cmu.edu>,
	David Howells <dhowells@redhat.com>, Tyler Hicks <code@tyhicks.com>,
	Miklos Szeredi <miklos@szeredi.hu>,
	Carlos Maiolino <cem@kernel.org>, linux-fsdevel@vger.kernel.org,
	coda@cs.cmu.edu, codalist@coda.cs.cmu.edu,
	linux-nfs@vger.kernel.org, netfs@lists.linux.dev,
	ecryptfs@vger.kernel.org, linux-unionfs@vger.kernel.org,
	linux-xfs@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 5/5] Change vfs_mkdir() to unlock on failure.
Message-ID: <20250609053442.GC299672@ZenIV>
References: <>
 <20250609005009.GB299672@ZenIV>
 <174944652013.608730.3439111222517126345@noble.neil.brown.name>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Mon, Jun 09, 2025 at 03:22:00PM +1000, NeilBrown wrote:
> On Mon, 09 Jun 2025, Al Viro wrote:
> > On Mon, Jun 09, 2025 at 09:09:37AM +1000, NeilBrown wrote:
> > > Proposed changes to directory-op locking will lock the dentry rather
> > > than the whole directory.  So the dentry will need to be unlocked.
> > 
> > Please, repost your current proposal _before_ that one goes anywhere.
> > 
> 
> I've posted my proposal for the new API.  This makes the value of the
> vfs_mkdir() change clear (I hope).
> 
> Would you also like me to post the patches which introduce the new
> locking scheme?

Yes, seeing that the rest does not make much sense without that.

I would really like a description of that locking scheme as well,
TBH, but if you prefer to start with the patches, then so be it.

I can't promise a response tonight - going down in an hour or so
and I'd like to do enough reordering of #work.mount to be able
to post the initial variant of at least some of that in the
morning...