RFC: ABI support for special memory area

[Suprateeka R Hegde]

On 23-Feb-2017 09:49 PM, H.J. Lu wrote:
>  The default implementation of __gnu_mbind_setup is
>
> int
> __gnu_mbind_setup (unsigned int type, void *addr, size_t length)
> {
>   return 0;
> }
>
> which can be overridden by a different implementation at link-time.
>

Since this is a design that allows vendor specific extension and 
implementation, would it OK if we make it more generic?

Instead of a fixed 3 arguments (type, addr, len), how about something 
like a pointer to a generic MBIND_CONTEXT struct (say of type 
__gnu_mbind_context defined)?  And let the implementation define the 
actual struct.

I would like to handle NVM/NVMe (long back I had mentioned about 
PT_PERSISTENT) through this MBIND and my implementation of handling 
NVM/NVMe needs more data to be passed to such "setup" functions.

Or is this __gnu_mbind_setup should be considered as a very basic / 
fundamental function (used just to setup the "memory area") and 
implementations/vendors are expected to write wrapper/handler functions 
to handle other aspects of the special memory? In that case the fixed 
set of basic args looks OK.

IMHO this __gnu_mbind_setup is a very good design to be generic enough 
and not be very specific/basic/fundamental runtime support.

--
Supra