Re: update on the device driver framework

[Simon Kagstrom]

On 2003-08-26, 21:34, Peter 'p2' De Schrijver wrote:
> Hi,
> 
> Attached you will find an updated version of the l4/hurd device driver
> framework design document.  
> 
> Thanks,
> 
> Daniel & Peter (in random order).
>   With this assumption, the device driver framework can be given any
>   physical memory page for DMA operation.  This physical memory page
>   must be pinned down.
> 
>   If an application wants to send or receive data to/from a device driver
>   it has to tell the virtual driver the page on which the operation
>   has to be executed.  Since the application doesn't know the
>   virtual-real memory mapping, it has to ask the physical memory
>   manager for the real memory address of the page in question.  If the
>   page is not directly mapped from the physical memory manager the
>   application ask the mapper (another application which has mapped
>   this memory region the first application) to resolve the mapping.
>   This can be done recursively.  Normally, this resolving of
>   mapping can be speed up using a cache services, since a small number
>   of pages are reused very often.

Hello!

In mine and Rickard Molins thesis, we discussed address translation problems
for a multisever environment upon L4 a bit. Don't know how much it is of
interest to you hurd people, but the thesis is available on

www.ipd.bth.se/ska/sim_home/filer/thesis.pdf

Regards,
// Simon Kagstrom