Re: [git pull] vfs pile, part 2

[Al Viro <viro@ZenIV.linux.org.uk>]

On Fri, May 28, 2010 at 12:27:51PM -0700, Sage Weil wrote:
> Hi Al,
> 
> There are two patches
> 
>  1f24668c vfs: make real_lookup do dentry revalidation with i_mutex held
>  982ddae4 vfs: clean up do_lookup()
> 
> that were in your for-next a few weeks back but aren't anymore (they're 
> still in your autofs branch).  I just want to make sure those don't get 
> lost if they're not going to make it upstream this time around?  I think 
> they've been in vfs-2.6.git limbo for two release cycles now.

My apologies, I thought you'd been Cc'd on the discussions with Ian concerning
that stuff, but...

The bottom line: "autofs4: always use lookup for lookup" is needed for them
and it had to be reverted since it'd been FUBAR.

Details: we really, *really* can not do things in ->d_revalidate() and count
on ->lookup() to come and finish them.  Think for a minute and you'll see why -
between these two calls we allocate a dentry to pass to ->lookup().  What
happens if that allocation fails?

And without that patch your stuff breaks autofs4.  So it's waiting for the
->d_revalidate() interface redesign.  Hopefully in the coming cycle...