Re: [PATCH] Add __vunmap prototype

["Satyam Sharma" <satyam.sharma@gmail.com>]

On 5/14/07, Benjamin Herrenschmidt <benh@kernel.crashing.org> wrote:
> On Mon, 2007-05-14 at 00:16 -0700, Andrew Morton wrote:
> > On Mon, 14 May 2007 17:07:03 +1000 Benjamin Herrenschmidt <benh@kernel.crashing.org> wrote:
> >
> > > __vunmap is not static but I couldn't find a prototype for it, so this
> > > adds it. I need to use it in some powerpc patch to come.
> > >
> > > Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> > >
> > >  include/linux/vmalloc.h |    1 +
> > >  1 file changed, 1 insertion(+)
> > >
> > > Index: linux-cell/include/linux/vmalloc.h
> > > ===================================================================
> > > --- linux-cell.orig/include/linux/vmalloc.h 2007-05-14 16:03:42.000000000 +1000
> > > +++ linux-cell/include/linux/vmalloc.h      2007-05-14 16:03:47.000000000 +1000
> > > @@ -50,6 +50,7 @@ extern void vfree(void *addr);
> > >  extern void *vmap(struct page **pages, unsigned int count,
> > >                     unsigned long flags, pgprot_t prot);
> > >  extern void vunmap(void *addr);
> > > +extern void __vunmap(void *addr, int deallocate_pages);
> > >
> > >  extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
> > >                                                     unsigned long pgoff);
> >
> > um, the only possible reason for wanting to access __vunmap() is that you
> > want to do vunmap() from interrupt context, which is deadlockable.
>
> Argh... I'm stupid, ignore it !
>
> I just want to __vunmap(addr, 0); which is just what vunmap() does :-)
>
> Why is __vunmap not static btw ? If there's no reason, I'll send a patch
> to make it so.

Yeah, it has no users outside mm/vmalloc.c and is not
EXPORT_SYMBOL'ed anyway (plus it's a BUG from in_interrupt() as
Andrew says, so must be called as either vfree() or vunmap()), so clearly
it does want to be static.