On 10/17/23 12:00 AM, Joao Martins wrote:
The iommu_dirty_bitmap is defined in iommu core. The iommu driver has no
need to understand it and check its member anyway.
(...) The iommu driver has no need to understand it. iommu_dirty_bitmap_record()
already makes those checks in case there's no iova_bitmap to set bits to.
This is all true but the reason I am checking iommu_dirty_bitmap::bitmap is to
essentially not record anything in the iova bitmap and just clear the dirty bits
from the IOPTEs, all when dirty tracking is technically disabled. This is done
internally only when starting dirty tracking, and thus to ensure that we cleanup
all dirty bits before we enable dirty tracking to have a consistent snapshot as
opposed to inheriting dirties from the past.
It's okay since it serves a functional purpose. Can you please add some
comments around the code to explain the rationale.
Best regards,
baolu
