> From: Joao Martins <joao.m.martins@xxxxxxxxxx> > Sent: Thursday, October 19, 2023 4:27 AM > > Underneath it uses the IOMMU domain kernel API which will read the dirty > bits, as well as atomically clearing the IOPTE dirty bit and flushing the > IOTLB at the end. The IOVA bitmaps usage takes care of the iteration of the what does 'atomically' try to convey here? > +/** > + * struct iommu_hwpt_get_dirty_iova - > ioctl(IOMMU_HWPT_GET_DIRTY_IOVA) IOMMU_HWPT_GET_DIRTY_BITMAP? IOVA usually means one address but here we talk about a bitmap of which one bit represents a page. > + * @size: sizeof(struct iommu_hwpt_get_dirty_iova) > + * @hwpt_id: HW pagetable ID that represents the IOMMU domain. > + * @flags: Flags to control dirty tracking status. > + * @iova: base IOVA of the bitmap first bit > + * @length: IOVA range size > + * @page_size: page size granularity of each bit in the bitmap > + * @data: bitmap where to set the dirty bits. The bitmap bits each > + * represent a page_size which you deviate from an arbitrary iova. > + * Checking a given IOVA is dirty: > + * > + * data[(iova / page_size) / 64] & (1ULL << (iova % 64)) (1ULL << ((iova / page_size) % 64) Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
