Re: [RFC] Simple userspace interface for PCI drivers

[Greg KH <greg@kroah.com>]

On Thu, Aug 31, 2006 at 09:36:08PM -0400, Brice Goglin wrote:
> I might be nice to have something like a copy-block where the
> application writes/reads data, while the device does DMA only from/to
> there. We would need an easy way to mmap some anonymous DMA-ready memory
> in user-space, and something to give the corresponding DMA addresses to
> the application.

Sure, send a patch :)

> Additionally, the current code might not be flexible enough regarding
> acknowledging of interrupts. It might be good to use the bit that PCI
> 2.2 defines in the config space to mask/unmask interrupt in a generic
> way. Something like : when an interrupt comes, the driver mask the
> interrupts using this bit, and then passes the event to user-space. The
> user-space interrupt handler acknowledges the interrupt with the device
> specific code, and then unmask with the PCI 2.2 bit.

You can do that today with this code.  Remember, you have to have a
tiny kernelspace portion of your driver to handle the interrupt.  You
can do whatever you want in that interrupt handler.

thanks,

greg k-h