Re: [PATCH v4] mmc: Add ioctl to let userspace apps send ACMDs

John Calixto
2011-04-18T16:31:11Z

On Mon, 18 Apr 2011, Arnd Bergmann wrote:
> On Wednesday 13 April 2011, John Calixto wrote:
> > Gah! OK, so much for the v5 I just sent then. What do you think about
> > the compat_ioctl that I sent in v2? It means having the extra 32-bit
> > compat structure, but at least all the compat overhead is conditional
> > upon CONFIG_COMPAT. If you're not using CONFIG_COMPAT, you don't get
> > any compat cruft.
> >
>
> A single __u64 is sufficient, because the user space will do the correct
> conversion from pointer to 64-bit integer then. The only conversion
> you need to worry about is the actual pointer to the main structure,
> which needs the compat_ptr() magic.
>

Yep. Please see the v6 patch for my latest implementation.

John