Re: [PATCH 20/24] XSM: fold xsm_{,un}map_domain_pirq() hooks

[Jan Beulich <jbeulich@xxxxxxxx>]

On 13.08.2026 14:42, Daniel P. Smith wrote:
> On 8/6/26 3:36 AM, Jan Beulich wrote:
>> On 06.08.2026 03:10, Daniel P. Smith wrote:
>>> On 7/28/26 9:23 AM, Jan Beulich wrote:
>>>> --- a/xen/xsm/flask/hooks.c
>>>> +++ b/xen/xsm/flask/hooks.c
>>>> @@ -1022,14 +1022,9 @@ static char *cf_check flask_show_irq_sid
>>>>    
>>>>    #ifdef CONFIG_HAS_PIRQ
>>>>    
>>>> -static int cf_check flask_map_domain_pirq(struct domain *d)
>>>> +static int cf_check flask_map_domain_pirq(struct domain *d, bool access)
>>>>    {
>>>> -    return current_has_perm(d, SECCLASS_RESOURCE, RESOURCE__ADD);
>>>> -}
>>>> -
>>>> -static int cf_check flask_unmap_domain_pirq(struct domain *d)
>>>> -{
>>>> -    return current_has_perm(d, SECCLASS_RESOURCE, RESOURCE__REMOVE);
>>>> +    return current_has_perm(d, SECCLASS_RESOURCE, 
>>>> resource_to_perm(access));
>>>>    }
>>>>    
>>>>    #endif /* CONFIG_HAS_PIRQ */
>>>>
>>>
>>> I am not opposed to collapsing the calls as long as the semantic is not
>>> lost, which I feel the reuse of the xsm_map_domain_pirq does looses it
>>> much less provides an opportunity for confusion. Something like
>>> xsm_domain_pirq(..., access) makes more semantic sense to me, as it
>>> would read, grant domain pirq access T/F.
>>
>> In fact I was as well wondering about naming (and a possible name change)
>> here. I decided against it because of the other hooks (touched by patch
>> 19), which all follow a similar model of their names really more expressing
>> the "positive" form than the "negative" one. Further, entirely losing "map"
>> from the name also doesn't look quite right, as physdev_{,un}map_pirq() is
>> where they're called from. To follow the naming of some of the other hook,
>> maybe xsm_domain_pirq_mapping(..., bool map)? Possibly even with "domain"
>> dropped from the name, fully fitting xsm_io{mem,port}_mapping()? Which
>> would then further raise the question whether patch 19 should maybe rename
>> the parameters of those two hooks to "map" at the same time.
> 
> Sound like you and I were running through the same argument with 
> ourselves, except you went right and I went left.
> 
> For me, I find the false case of xsm_map_domain_pirq(..., access) reads 
> a bit weird, "Can the target map domain pirq access=false?" I do like 
> your mapping suggestion along with the parameter rename to map. It 
> changes the reading to "Is target allowed map(true)/unmap(false) for the 
> domain pirq mapping?" This could be carried through to the other cases.

Will do. As to patch 19: I'm inclined to leave the parameters as "allow"
in dummy.h, but change at least the flask_io{mem,port}_mapping() ones to
"map". Will that be okay with you? Else what scheme would you prefer?

Jan