Re: [PATCH v2 4/4] iommu/vt-d: Remove hard coding PGSNP bit in PASID entries

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

On 2022/5/5 16:46, Tian, Kevin wrote:
>> From: Lu Baolu <baolu.lu@linux.intel.com>
>> Sent: Thursday, May 5, 2022 9:07 AM
>>
>> As enforce_cache_coherency has been introduced into the
>> iommu_domain_ops,
>> the kernel component which owns the iommu domain is able to opt-in its
>> requirement for force snooping support. The iommu driver has no need to
>> hard code the page snoop control bit in the PASID table entries anymore.
>>
>> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
> 
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>, with one nit:
> 
>> ---
>>   drivers/iommu/intel/pasid.c | 3 ---
>>   1 file changed, 3 deletions(-)
>>
>> diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c
>> index 41a0e3b02c79..0abfa7fc7fb0 100644
>> --- a/drivers/iommu/intel/pasid.c
>> +++ b/drivers/iommu/intel/pasid.c
>> @@ -710,9 +710,6 @@ int intel_pasid_setup_second_level(struct
>> intel_iommu *iommu,
>>   	pasid_set_fault_enable(pte);
>>   	pasid_set_page_snoop(pte, !!ecap_smpwc(iommu->ecap));
> 
> Probably in a separate patch but above should really be renamed
> to pasid_set_page_walk_snoop().

Yeah! Need a cleanup here. Above name is confusing.

> 
>>
>> -	if (domain->domain.type == IOMMU_DOMAIN_UNMANAGED)
>> -		pasid_set_pgsnp(pte);
>> -
>>   	/*
>>   	 * Since it is a second level only translation setup, we should
>>   	 * set SRE bit as well (addresses are expected to be GPAs).
>> --
>> 2.25.1
> 

Best regards,
baolu