iommu/vt-d: Add a fix for devices need extra dtlb flush
QAT devices on Intel Sapphire Rapids and Emerald Rapids have a defect in address translation service (ATS). These devices may inadvertently issue ATS invalidation completion before posted writes initiated with translated address that utilized translations matching the invalidation address range, violating the invalidation completion ordering. This patch adds an extra device TLB invalidation for the affected devices, it is needed to ensure no more posted writes with translated address following the invalidation completion. Therefore, the ordering is preserved and data-corruption is prevented. Device TLBs are invalidated under the following six conditions: 1. Device driver does DMA API unmap IOVA 2. Device driver unbind a PASID from a process, sva_unbind_device() 3. PASID is torn down, after PASID cache is flushed. e.g. process exit_mmap() due to crash 4. Under SVA usage, called by mmu_notifier.invalidate_range() where VM has to free pages that were unmapped 5. userspace driver unmaps a DMA buffer 6. Cache invalidation in vSVA usage (upcoming) For #1 and #2, device drivers are responsible for stopping DMA traffic before unmap/unbind. For #3, iommu driver gets mmu_notifier to invalidate TLB the same way as normal user unmap which will do an extra invalidation. The dTLB invalidation after PASID cache flush does not need an extra invalidation. Therefore, we only need to deal with #4 and #5 in this patch. #1 is also covered by this patch due to common code path with #5. Tested-by: Yuzhang Luo <yuzhang.luo@intel.com> Reviewed-by: Ashok Raj <ashok.raj@intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Link: https://lore.kernel.org/r/20221130062449.1360063-1-jacob.jun.pan@linux.intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
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