1d72e31c9SAlex WilliamsonWhat: /sys/kernel/iommu_groups/ 2d72e31c9SAlex WilliamsonDate: May 2012 3d72e31c9SAlex WilliamsonKernelVersion: v3.5 4d72e31c9SAlex WilliamsonContact: Alex Williamson <alex.williamson@redhat.com> 5d72e31c9SAlex WilliamsonDescription: /sys/kernel/iommu_groups/ contains a number of sub- 6d72e31c9SAlex Williamson directories, each representing an IOMMU group. The 7d72e31c9SAlex Williamson name of the sub-directory matches the iommu_group_id() 8d72e31c9SAlex Williamson for the group, which is an integer value. Within each 9d72e31c9SAlex Williamson subdirectory is another directory named "devices" with 10d72e31c9SAlex Williamson links to the sysfs devices contained in this group. 11d72e31c9SAlex Williamson The group directory also optionally contains a "name" 12d72e31c9SAlex Williamson file if the IOMMU driver has chosen to register a more 13d72e31c9SAlex Williamson common name for the group. 14d72e31c9SAlex WilliamsonUsers: 15bc7d12b9SEric Auger 16bc7d12b9SEric AugerWhat: /sys/kernel/iommu_groups/reserved_regions 17bc7d12b9SEric AugerDate: January 2017 18bc7d12b9SEric AugerKernelVersion: v4.11 19bc7d12b9SEric AugerContact: Eric Auger <eric.auger@redhat.com> 20bc7d12b9SEric AugerDescription: /sys/kernel/iommu_groups/reserved_regions list IOVA 21bc7d12b9SEric Auger regions that are reserved. Not necessarily all 22bc7d12b9SEric Auger reserved regions are listed. This is typically used to 23bc7d12b9SEric Auger output direct-mapped, MSI, non mappable regions. Each 24bc7d12b9SEric Auger region is described on a single line: the 1st field is 25bc7d12b9SEric Auger the base IOVA, the second is the end IOVA and the third 26bc7d12b9SEric Auger field describes the type of the region. 27*adfd3738SEric Auger 28*adfd3738SEric AugerWhat: /sys/kernel/iommu_groups/reserved_regions 29*adfd3738SEric AugerDate: June 2019 30*adfd3738SEric AugerKernelVersion: v5.3 31*adfd3738SEric AugerContact: Eric Auger <eric.auger@redhat.com> 32*adfd3738SEric AugerDescription: In case an RMRR is used only by graphics or USB devices 33*adfd3738SEric Auger it is now exposed as "direct-relaxable" instead of "direct". 34*adfd3738SEric Auger In device assignment use case, for instance, those RMRR 35*adfd3738SEric Auger are considered to be relaxable and safe. 36