[PATCH v9 2/3] kernel.h: add to_user_ptr()

[Joe Perches]

On Thu, 2016-03-17 at 18:19 -0300, Gustavo Padovan wrote:
> 2016-03-17 Joe Perches <joe at perches.com>:
> > On Thu, 2016-03-17 at 16:50 -0400, Rob Clark wrote:
> > > On Thu, Mar 17, 2016 at 4:40 PM, Joe Perches <joe at perches.com> wrote:
> > []
> > > > It's a name that seems like it should be a straightforward
> > > > cast of a kernel pointer to a __user pointer like:
> > > > 
> > > > static inline void __user *to_user_ptr(void *p)
> > > > {
> > > >         return (void __user *)p;
> > > > }
> > > ahh, ok.  I guess I was used to using it in the context of ioctl
> > > structs..  in that context u64 -> (void __user *) made more sense.
> > > 
> > > Maybe uapi_to_ptr()?  (ok, not super-creative.. maybe someone has a
> > > better idea)
> > Maybe u64_to_user_ptr?
> That is a good name. If everyone agrees I can resend this patch
> changing it to u64_to_user_ptr. Then should we still keep it on
> kernel.h?

I've no particular opinion about location,
but maybe compat.h might be appropriate.

Maybe add all variants:

	void __user *u32_to_user_ptr(u32 val)
	void __user *u64_to_user_ptr(u64 val)
	u32 user_ptr_to_u32(void __user *p)
	u64 user_ptr_to_u64(void __user *p)

Maybe there's something about 32 bit userspace on
64 OS that should be done too.