Translated - Strict

configname: CONFIG_IOMMU_DEFAULT_DMA_STRICT

IOMMU default domain type
└─>Translated - Strict
In linux kernel since version 5.2 (release Date: 2019-07-07)  
Trusted devices use translation to restrict their access to only
DMA-mapped pages, with strict TLB invalidation on unmap. Equivalent
to passing "iommu.passthrough=0 iommu.strict=1" on the command line.

Untrusted devices always use this mode, with an additional layer of
bounce-buffering such that they cannot gain access to any unrelated
data within a mapped page.