[PATCH v2 0/5] iommu/virtio: Add identity domains

[Jean-Philippe Brucker]

Support identity domains, allowing to only enable IOMMU protection for a
subset of endpoints (those assigned to userspace, for example). Users
may enable identity domains at compile time
(CONFIG_IOMMU_DEFAULT_PASSTHROUGH), boot time (iommu.passthrough=1) or
runtime (/sys/kernel/iommu_groups/*/type = identity).

Since v1 [1] I rebased onto v5.16-rc and added Kevin's review tag.
The specification update for the new feature has now been accepted [2].

Patches 1-2 support identity domains using the optional
VIRTIO_IOMMU_F_BYPASS_CONFIG feature, and patches 3-5 add a fallback to
identity mappings, when the feature is not supported.

QEMU patches are on my virtio-iommu/bypass branch [3], and depend on the
UAPI update.

[1] https://lore.kernel.org/linux-iommu/20211013121052.518113-1-jean-philippe@xxxxxxxxxx/
[2] https://github.com/oasis-tcs/virtio-spec/issues/119
[3] https://jpbrucker.net/git/qemu/log/?h=virtio-iommu/bypass

Jean-Philippe Brucker (5):
  iommu/virtio: Add definitions for VIRTIO_IOMMU_F_BYPASS_CONFIG
  iommu/virtio: Support bypass domains
  iommu/virtio: Sort reserved regions
  iommu/virtio: Pass end address to viommu_add_mapping()
  iommu/virtio: Support identity-mapped domains

 include/uapi/linux/virtio_iommu.h |   8 ++-
 drivers/iommu/virtio-iommu.c      | 113 +++++++++++++++++++++++++-----
 2 files changed, 101 insertions(+), 20 deletions(-)

-- 
2.33.1