Re: [PATCH] xen: Fix BUFIOREQ evtchn init for a stubdom.

[Anthony PERARD <anthony.perard@citrix.com>]

On Tue, Jun 26, 2012 at 3:21 PM, Ian Campbell <Ian.Campbell@citrix.com> wrote:
> On Tue, 2012-06-26 at 15:13 +0100, Anthony PERARD wrote:
>> On Tue, Jun 26, 2012 at 11:54 AM, Ian Campbell <Ian.Campbell@citrix.com> wrote:
>> > On Tue, 2012-06-26 at 11:45 +0100, Anthony PERARD wrote:
>> >> This is a missing part from the previous patch that add the BUFIOREQ_EVTCHN
>> >> parameter. This patch changes the ownership of the buifioreq event channel to
>> >> the stubdom (when HVM_PARAM_DM_DOMAIN is set within the stubdom).
>> >>
>> >> This fix the initialization of QEMU inside the stubdomain.
>> >>
>> >> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
>> >
>> > This fixes stub domains for me, thanks.
>> >
>> > The user of this field (hvm_buffered_io_send) takes iorp->lock so we
>> > probably want to put the update inside that too, just like for the
>> > non-buffered case?
>>
>> Will do.
>>
>> > It would be nice to extract the alloc&replace functionality into a
>> > helper.
>>
>> I tried but it does not work well.
>> xen_port is an it (non-buffer case) and params[bufioreq...] is an
>> uint64_t. Both should be argument of the helper, as a pointer to be
>> pass to xchg().
>>
>> The prototype of the not working helper:
>> static int hvm_replace_event_channel(struct vcpu *v, uint64_t
>> remote_domid, int *port)
>>
>> So unless there is another way to create this helper, there won't be any.
>
> Although params[...] are generally uint64_t the params[BUFIOREQ_EVTCHN]
> is really an int (or more properly an evtchn_port_t, although this is
> only used in include/public). Perhaps a cast is appropriate in this
> case?

All right, I will cast.

-- 
Anthony PERARD