Re: [PATCH RFC v3 04/12] iommu/sva: Basic data structures for SVA

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

On 2022/4/12 14:49, Tian, Kevin wrote:
>> From: Lu Baolu <baolu.lu@linux.intel.com>
>> Sent: Sunday, April 10, 2022 6:25 PM
>>
>> Use below data structures for SVA implementation in the IOMMU core:
>>
>> - struct iommu_sva_ioas
>>    Represent the I/O address space shared with an application CPU address
>>    space. This structure has a 1:1 relationship with an mm_struct. It
>>    graps a "mm->mm_count" refcount during creation and drop it on release.
>>
>> - struct iommu_domain (IOMMU_DOMAIN_SVA type)
>>    Represent a hardware pagetable that the IOMMU hardware could use for
>>    SVA translation. Multiple iommu domains could be bound with an SVA ioas
>>    and each graps a refcount from ioas in order to make sure ioas could
>>    only be freed after all domains have been unbound.
>>
>> - struct iommu_sva
>>    Represent a bond relationship between an SVA ioas and an iommu domain.
>>    If a bond already exists, it's reused and a reference is taken.
>>
>> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
> 
> This should be patch07. None of following patches touch those structures
> until hitting patch08.

The iommu_sva_domain_mm() helper will be used in the following patches.

Best regards,
baolu