[coyotos-dev] coyotos.ioperm

[Valerio Bellizzomi]

On 08/04/2007, at 2.39, Valerio Bellizzomi wrote:

>On 07/04/2007, at 8.19, Jonathan S. Shapiro wrote:
>
>>On Sat, 2007-04-07 at 00:55 +0200, Valerio Bellizzomi wrote:
>>> On 06/04/2007, at 11.31, Jonathan S. Shapiro wrote:
>>
>>> On this architecture we have three choices:
>>> >
>>> >  1. Make I/O rights be all or nothing. This is what the EROS IOperm
>>> >     capability did, and what the Coyotos IOperm capability was
>intended
>>> >     to do.
>>> >
>>> >  2. Come up with a way to memory map the IO bitmap. This is the
>>> >     solution that I prefer, but there are complications.
>>> 
>>> Did you forget the third choice ?
>>
>>Um. Yes. Use dynamic translation, and enforce the permission using the
>>translator.
>>
>>> The main reason I asked is that we need a way to control the state of
>>> individual pins of the parallel port. We are currently doing this with
>>> fedora, but we would like to use coyotos.
>>
>>I don't think that any decision about ioperms will change this. The
>>permissions bitmap is only going to control access to the parallel port
>>as a whole. If you want pin-level control, you're going to need to do
>>that with a software wrapper in any case. What the permissions bitmap is
>>going to control is the I/O permissions available to the wrapping
>>software.
>
>There will be a library to access hardware ports ?

Should I call it a wrapper library ?