Xen bus drivers and the probe function

Xen bus drivers and the probe function

[Michael Abd-El-Malek]

Hello,

I'm writing a split driver for XenBus.  My understanding is that this is 
the "Xen way" for inter-domain discovery, bootstrapping the process by 
sharing grants and event channels.

When I look at the block driver, the probe method of the front- and 
back-ends seems to be doing the bulk of the initialization work.  In my 
sample driver, however, my probe function isn't called.  My module gets 
inserted and the initialization function correctly installs the XenBus 
driver.

Can someone please explain when the probe function is supposed to be 
called?  If there's no physical device "backing" the virtual device 
(i.e., virtual block driver is a counterexample), should I be relying on 
the probe method in the first place?

Thanks,
Mike

Re: Xen bus drivers and the probe function

[Keir Fraser]

Bootstrap needs to be initiated by xend, which writes initial rendezvous
information into xenstore. See DevController.py in xend.

 -- Keir

On 2/10/07 06:39, "Michael Abd-El-Malek" <mabdelmalek@cmu.edu> wrote:

> Hello,
> 
> I'm writing a split driver for XenBus.  My understanding is that this is
> the "Xen way" for inter-domain discovery, bootstrapping the process by
> sharing grants and event channels.
> 
> When I look at the block driver, the probe method of the front- and
> back-ends seems to be doing the bulk of the initialization work.  In my
> sample driver, however, my probe function isn't called.  My module gets
> inserted and the initialization function correctly installs the XenBus
> driver.
> 
> Can someone please explain when the probe function is supposed to be
> called?  If there's no physical device "backing" the virtual device
> (i.e., virtual block driver is a counterexample), should I be relying on
> the probe method in the first place?
> 
> Thanks,
> Mike
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel

Re: Xen bus drivers and the probe function

[Ryan Riley]

As Keir said, the probe() function gets triggered by the right things
appearing in the XenStore.  The XenIntro wiki has an example of this
in section 23 (Adding a new device and triggering...):
http://wiki.xensource.com/xenwiki/XenIntro

Hopefully that will be helpful for you.

Thanks
Ryan

On 10/2/07, Michael Abd-El-Malek <mabdelmalek@cmu.edu> wrote:
> Hello,
>
> I'm writing a split driver for XenBus.  My understanding is that this is
> the "Xen way" for inter-domain discovery, bootstrapping the process by
> sharing grants and event channels.
>
> When I look at the block driver, the probe method of the front- and
> back-ends seems to be doing the bulk of the initialization work.  In my
> sample driver, however, my probe function isn't called.  My module gets
> inserted and the initialization function correctly installs the XenBus
> driver.
>
> Can someone please explain when the probe function is supposed to be
> called?  If there's no physical device "backing" the virtual device
> (i.e., virtual block driver is a counterexample), should I be relying on
> the probe method in the first place?
>
> Thanks,
> Mike
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel
>