Re: plan to work on user-level device drivers

[olafBuddenhagen]

Hi,

On Thu, Jul 16, 2009 at 12:04:21PM +0800, Da Zheng wrote:
>> On Tue, Jul 07, 2009 at 01:33:17PM +0800, Da Zheng wrote:

>>> * Does the small interrupt routine in the kernel already exists?
>>
>> The problem is that this routine is actually pretty device-specific.
>> In Linux UIO at least, every driver comes with a small kernel module
>> handling this -- though I wonder whether it wouldn't be possible to
>> upload a description is some simplistic "safe" language to the kernel
>> at runtime, so we don't need to add any "real" (machine) code to the
>> kernel for each new device.
>>   
> Minix3 provides a generic interrupt handler in the kernel and the
> user-level driver can provide different policies. I guess we can do
> the same.

Indeed that's exactly what I meant: only I don't know how complex the
policies need to be, so I kept my statement generic. (In theory, the
method for disabling interrupts on any particular device can be
arbitrarily complex -- the question is how complex it gets in devices
actually existing in the real world...) If the "language" really boils
down to a few simple declarations, all the better :-)

-antrik-