Messages in this thread | | | Date | Mon, 31 May 2010 07:45:03 -0300 | From | Cesar Eduardo Barros <> | Subject | Re: [PATCH] Make kunmap_atomic() harder to misuse |
| |
Em 31-05-2010 07:15, Rusty Russell escreveu: > On Sun, 30 May 2010 01:12:56 pm Andrew Morton wrote: >> On Fri, 28 May 2010 07:53:13 -0300 Cesar Eduardo Barros<cesarb@cesarb.net> wrote: >>> +/* Prevent people trying to call kunmap_atomic() as if it were kunmap() */ >>> +struct __kunmap_atomic_dummy {}; >>> +#define kunmap_atomic(addr, idx) do { \ >>> + BUILD_BUG_ON( \ >>> + __builtin_types_compatible_p(typeof(addr), struct page *)&& \ >>> + !__builtin_types_compatible_p(typeof(addr), struct __kunmap_atomic_dummy *)); \ >>> + kunmap_atomic_notypecheck((addr), (idx)); \ >>> + } while (0) >> >> We have a little __same_type() helper for this. __must_be_array() >> should be using it, too. > > Yep... but I think BUILD_BUG_ON(__same_type((addr), struct page *)); is > sufficient; void * is not compatible in my quick tests here.
That is what I get for only reading the manual instead of testing :(
(I only tested the completed patch, not each step along the way.)
I will try it later today and make a new patch if it works as expected.
-- Cesar Eduardo Barros cesarb@cesarb.net cesar.barros@gmail.com
| |