[PATCH v3 59/62] xen/arm: Add a hypercall for device mmio mapping

Jan Beulich JBeulich at suse.com
Thu Jan 7 02:50:44 PST 2016


>>> On 07.01.16 at 10:11, <zhaoshenglong at huawei.com> wrote:
> Hi Jan,
> 
> On 2016/1/7 15:45, Jan Beulich wrote:
>>>>> On 07.01.16 at 07:58, <zhaoshenglong at huawei.com> wrote:
>>> > On 2015/11/17 19:04, Jan Beulich wrote:
>>>>>>> >>>>> On 17.11.15 at 10:40, <shannon.zhao at linaro.org> wrote:
>>>>>> >>> > --- a/xen/arch/arm/mm.c
>>>>>> >>> > +++ b/xen/arch/arm/mm.c
>>>>>> >>> > @@ -1138,6 +1138,10 @@ int xenmem_add_to_physmap_one(
>>>>>> >>> >          rcu_unlock_domain(od);
>>>>>> >>> >          break;
>>>>>> >>> >      }
>>>>>> >>> > +    case XENMAPSPACE_dev_mmio:
>>>>>> >>> > +        rc = map_dev_mmio_region(d, gpfn, 1, idx);
>>>>>> >>> > +        return rc;
>>>>>> >>> > +        break;
>>>> >> Blindly for any kind of domain? The XSM check in the
>>>> >> XENMEM_add_to_physmap_batch handler (in common code) doesn't
>>>> >> even know which map space is to be used...
>>> > 
>>> > Sorry, I know little about XSM. Could you suggest me how to add the
>>> > check for this new type here?
>> I'm sorry to push back here, but did you at least try to derive
>> what is wanted from the multitude of other XSM checks present
>> throughout the tree?
> 
> IIUC, you mean that it doean't need to change the XSM check itself, but
> we should check if the current->domain is hardware domain and it maps
> the space to itself before the XSM check, right?

No, I actually think that you need to add a new, secondary XSM
check. But you may want to consult with Daniel (who so far wasn't
even Cc-ed).

Jan




More information about the linux-arm-kernel mailing list