Re: [PATCH 2.4.19pre8][RFC] remove-NFS-close-to-open from VFS (was Re: [PATCHSET] 2.4.19-pre8-jp12)

[Jan Harkes <jaharkes@cs.cmu.edu>]

On Fri, Oct 18, 2002 at 01:57:17AM +0200, Trond Myklebust wrote:
> Client                         Server
> ------                         --------
> cd foo
>                                mv foo bar
> open(".")
> 
> You are basically saying that you believe that the above scenario must
> always fail and that the VFS should enforce a violation of POSIX
> rules. The current code has the possibility to recover from the above
> sort of thing: this will not be the case if you have to look up 'foo'
> on the server in order to do open(".")

I must be blind, because nfs_lookup_revalidate does,

    dir = dentry->d_parent->d_inode;
    ...
    error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, &fhandle, &fattr);
    if (error)
	goto out_bad;

So how is this recovering any better from the scenario you just gave?

> So? That's just because those lines usually lie just after a
> cached_lookup(), which bumps the count. Read the code in question: it
> is not leaking dentries.

Ah, got confused by the dput in the out_dput path, must have missed the
return 0; right above it.

Jan