PERFORCE change 122480 for review

[Roman Divacky]

On Fri, Jun 29, 2007 at 08:52:06PM -0400, John Baldwin wrote:
> On Thursday 28 June 2007 08:14:43 am Roman Divacky wrote:
> > http://perforce.freebsd.org/chv.cgi?CH=122480
> > 
> > Change 122480 by rdivacky at rdivacky_witten on 2007/06/28 12:14:14
> > 
> > 	vrele AFTER checking the vp for being on non-MPSAFE FS +  some indentation
> > 	problems that caused bad scoping
> > 	
> > 	Noticed by: rwatson (again ;) )
> 
> Umm, no.  You need Giant for the vrele().  The proper fix is to use the 
> VFS_*_GIANT() macros and use int variables to know if you need to unlock 
> Giant or not.

I dont see an easy and elegant way how to use the VFS_*_GIANT macros. I lock
the giant in kern_get_at() function and unlock in function that calls this one. ie.:

foo()
{
   kern_get_at(...);
   ...
   if (VFS_NEEDSGIANT)
         mtx_unlock(&Giant);
}

I need to either propagate the vfslocked value from kern_get_at or lock the Giant in the foo()
function. honestly I dont like either much

what do you suggest?