Re: [RFC v8 3/5] memory: Add IOMMU_DEVIOTLB_UNMAP IOMMUTLBNotificationType

[Auger Eric]

Hi Eugenio,
On 9/3/20 12:13 PM, Eugenio Perez Martin wrote:
> Hi Eric,
> 
> On Wed, Sep 2, 2020 at 12:32 PM Auger Eric <eric.auger@redhat.com> wrote:
>>
>> Hi Eugenio,
>>
>> On 9/1/20 4:26 PM, Eugenio Pérez wrote:
>>> Adapt intel and vhost to use this new notification type
>> I think you should explain in the commit message what is the benefice to
>> introduce this new event type.
> 
> Will do, thanks!
> 
>>>
>>> Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
>>> ---
>>>  hw/i386/intel_iommu.c | 2 +-
>>>  hw/virtio/vhost.c     | 2 +-
>>>  include/exec/memory.h | 2 ++
>>>  3 files changed, 4 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
>>> index 0c4aef5cb5..cdddb089e7 100644
>>> --- a/hw/i386/intel_iommu.c
>>> +++ b/hw/i386/intel_iommu.c
>>> @@ -2468,7 +2468,7 @@ static bool 
>>> vtd_process_device_iotlb_desc(IntelIOMMUState *s,
>>>          sz = VTD_PAGE_SIZE;
>>>      }
>>>
>>> -    event.type = IOMMU_NOTIFIER_UNMAP;
>>> +    event.type = IOMMU_NOTIFIER_DEVIOTLB;
>> If this is used only for device IOTLB cache invalidation, shouldn't this
>> be named IOMMU_NOTIFIER_DEVIOTLB_UNMAP to be consistent with the rest?
>>>      event.entry.target_as = &vtd_dev_as->as;
>>>      event.entry.addr_mask = sz - 1;
>>>      event.entry.iova = addr;
>>> diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
>>> index 1a1384e7a6..6ca168b47e 100644
>>> --- a/hw/virtio/vhost.c
>>> +++ b/hw/virtio/vhost.c
>>> @@ -729,7 +729,7 @@ static void vhost_iommu_region_add(MemoryListener 
>>> *listener,
>>>      iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr,
>>>                                                     MEMTXATTRS_UNSPECIFIED);
>>>      iommu_notifier_init(&iommu->n, vhost_iommu_unmap_notify,
>>> -                        IOMMU_NOTIFIER_UNMAP,
>>> +                        IOMMU_NOTIFIER_DEVIOTLB,
>>>                          section->offset_within_region,
>>>                          int128_get64(end),
>>>                          iommu_idx);
>>> diff --git a/include/exec/memory.h b/include/exec/memory.h
>>> index 8a56707169..215e23973d 100644
>>> --- a/include/exec/memory.h
>>> +++ b/include/exec/memory.h
>>> @@ -87,6 +87,8 @@ typedef enum {
>>>      IOMMU_NOTIFIER_UNMAP = 0x1,
>>>      /* Notify entry changes (newly created entries) */
>>>      IOMMU_NOTIFIER_MAP = 0x2,
>>> +    /* Notify changes on device IOTLB entries */
>>> +    IOMMU_NOTIFIER_DEVIOTLB = 0x04,
>>>  } IOMMUNotifierFlag;
>>>
>>>  #define IOMMU_NOTIFIER_ALL (IOMMU_NOTIFIER_MAP | IOMMU_NOTIFIER_UNMAP)
>> shouldn't we rename this one??
>>>
>>
> 
> Agree, but I'm not sure about the right name. IOMMU_NOTIFIER_ALL_ROOT?
> IOMMU_NOTIFIER_ALL_REGULAR?
I would rather name it IOMMU_NOTIFIER_IOTLB_EVENTS versus
IOMMU_NOTIFIER_DEVIOTLB_EVENTS? This is the cache type that differs,
isn't it?

Thanks

Eric
> 
> Thanks!
> 
>> Thanks
>>
>> Eric
>>
> 
>