Re: [PATCH v2 2/3] iommu: Consolidate pasid dma ownership check

[Baolu Lu <baolu.lu@linux.intel.com>]

On 2023/8/18 13:43, Nicolin Chen wrote:
> On Mon, Aug 14, 2023 at 09:17:58AM +0800, Lu Baolu wrote:
> 
>> When switching device DMA ownership, it is required that all the device's
>> pasid DMA be disabled. This is done by checking if the pasid array of the
>> group is empty. Consolidate all the open code into a single helper. No
>> intentional functionality change.
>>
>> Signed-off-by: Lu Baolu<baolu.lu@linux.intel.com>
>> ---
>>   drivers/iommu/iommu.c | 23 ++++++++++++++++++-----
>>   1 file changed, 18 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
>> index f1eba60e573f..d4a06a37ce39 100644
>> --- a/drivers/iommu/iommu.c
>> +++ b/drivers/iommu/iommu.c
>> @@ -3127,6 +3127,19 @@ static bool iommu_is_default_domain(struct iommu_group *group)
>>          return false;
>>   }
>>
>> +/*
>> + * Assert no PASID DMA when claiming or releasing group's DMA ownership.
>               ^
> 	     |...
> 
>> + * The device pasid interfaces are only for device drivers that have
>> + * claimed the DMA ownership. Return true if no pasid DMA setup, otherwise
>> + * return false with a WARN().
>> + */
>> +static bool assert_pasid_dma_ownership(struct iommu_group *group)
> ... should it be assert_no_pasid_dma_ownership?

Fair enough. Or, perhaps just assert_no_pasid_dma()?

Best regards,
baolu