Re: [PATCH 01/10] VFS: support parallel updates in the one directory.

[Al Viro]

On Mon, Aug 29, 2022 at 11:59:02AM +1000, NeilBrown wrote:

> > When would we get out of __lookup_hash() with in-lookup dentry?
> > Confused...
> 
> Whenever wq is passed in and ->lookup() decides, based on the flags, to do
> nothing.
> NFS does this for LOOKUP_CREATE|LOOKUP_EXCL and for LOOKUP_RENAME_TARGET

Frankly, I would rather do what all other callers of ->lookup() do and
just follow it with d_lookup_done(dentry), no matter what it returns.
It's cheap enough...