Re: Layered fs, vnode locking and v_vnlock removal

[Adam Hamsik <haaaad%gmail.com@localhost>]

> 
>> In the long run I intend to make all the vnode ops symmetric with
>> respect to locking, which should make a lot of this less toxic, but at
>> the rate I've been able to work on this stuff we won't be there
>> anytime soon.
> 
> The asymmetry comes from functions like null_mount() where a vnode gets
> locked by the lower layer and unlocked by the upper layer.  A lower
> layer expecting its VOP_LOCK() to be matched by a VOP_UNLOCK() will
> fail badly.
> 
> In the long term VOP_xxxLOCK() should become part of the file systems.

AFAIK there is a consensus between yamt@, ad@ and thorpej@ that locking should 
be moved down to the filesystems. There was some discussion about it here some 
time before.

Regards

Adam.