Re: Userspace I/O driver core

[Avi Kivity <avi@argo.co.il>]

[why trim the cc?]

Hans-Jürgen Koch wrote:
> Am Donnerstag, 14. Dezember 2006 10:44 schrieb Avi Kivity:
>
>   
>> I understand one still has to write a kernel driver to shut up the irq.  
>> How about writing a small bytecode interpreter to make event than 
>> unnecessary?
>>
>> The userspace driver would register a couple of bytecode programs: 
>> is_interrupt_pending() and disable_interrupt(), which the uio framework 
>> would call when the interrupt fires.
>>
>> The bytecode could reuse net/core/filter.c, with the packet replaced by 
>> the mmio or ioregion, or use something new.
>>
>>     
>
> I think this would be overkill. The kernel module you have to write
> is _really_ very simple. And it has to be written only once, so even
> a manufacturer who employs no experienced kernel developers can
> easily outsource that task.
>
>   

It has to be written once, but compiled for every kernel version and 
$arch out there (for out of tree drivers), or it has to wait for the 
next kernel release and distro sync (for in-tree drivers).

If we make userspace drivers possible, it makes sense that the entire 
driver be in userspace, not just 98.7% of it.



-- 
error compiling committee.c: too many arguments to function