Re: [Xenomai-help] RTDM mmap alternative

[Jan Kiszka <jan.kiszka@domain.hid>]

[-- Attachment #1: Type: text/plain, Size: 830 bytes --]

Rodrigo Rosenfeld Rosas wrote:
> One more doubt: how would I munmap that memory? do_munmap and passing 
> current->mm as the first parameter and the physical address as start? I'm not 

Yes, but better save current->mm at mmap time and pass *this* value on
unmap. I'm thinking about a way to include this in RTDM.

> sure... Maybe the user can call munmap directly since it doesn't need the 
> file descriptor. But which address should (s)he pass to start parameter, the 
> virtual or the physical one?

This is also an option. The user would have to pass the virtual address
the driver returned.

But I think we still need a cleanup on RTDM device closure to avoid
access to the mapped physical buffers after that point. I wonder how
this is done in standard drivers, will have to look at some of them.

Jan


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 252 bytes --]