Implement the virtio-iommu driver, following specification v0.8 [1].
Changes since v2 [2]:
* Patches 2-4 allow virtio-iommu to use the PCI transport, since QEMU
would like to phase out the MMIO transport. This produces a complex
topology where the programming interface of the IOMMU could appear
lower than the endpoints that it translates. It's not unheard of (e.g.
AMD IOMMU), and the guest easily copes with this.
The "Firmware description" section of the specification has been
updated with all combinations of PCI, MMIO and DT, ACPI.
* Fix structures layout, they don't need the "packed" attribute anymore.
* While we're at it, add domain parameter to DETACH request, and leave
some padding. This way the next version, that adds PASID support,
won't have to introduce a "DETACH2" request to stay backward
compatible.
* Require virtio device 1.0+. Remove legacy transport notes from the
specification.
* Request timeout is now only enabled with DEBUG.
* The patch for VFIO Kconfig (previously patch 5/5) is in next.
You can find Linux driver and kvmtool device on branches
virtio-iommu/v0.8 [3] (currently based on 4.19-rc7 but rebasing onto
next only produced a trivial conflict). Branch virtio-iommu/devel
contains a few patches that I'd like to send once the base is upstream:
* virtio-iommu as a module. It got *much* nicer after Rob's probe
deferral rework, but I still have a bug to fix when re-loading the
virtio-iommu module.
* ACPI support requires a minor IORT spec update (reservation of node
ID). I think it should be easier to obtain once the device and drivers
are upstream.
[1] Virtio-iommu specification v0.8, diff from v0.7, and sources
git://linux-arm.org/virtio-iommu.git virtio-iommu/v0.8
http://jpbrucker.net/virtio-iommu/spec/v0.8/virtio-iommu-v0.8.pdf
http://jpbrucker.net/virtio-iommu/spec/diffs/virtio-iommu-pdf-diff-v0.7-v0.8.pdf
[2] [PATCH v2 0/5] Add virtio-iommu driver
https://www.spinics.net/lists/kvm/msg170655.html
[3] git://linux-arm.org/linux-jpb.git virtio-iommu/v0.8
git://linux-arm.org/kvmtool-jpb.git virtio-iommu/v0.8
Jean-Philippe Brucker (7):
dt-bindings: virtio-mmio: Add IOMMU description
dt-bindings: virtio: Add virtio-pci-iommu node
PCI: OF: allow endpoints to bypass the iommu
PCI: OF: Initialize dev->fwnode appropriately
iommu: Add virtio-iommu driver
iommu/virtio: Add probe request
iommu/virtio: Add event queue
.../devicetree/bindings/virtio/iommu.txt | 66 +
.../devicetree/bindings/virtio/mmio.txt | 30 +
MAINTAINERS | 7 +
drivers/iommu/Kconfig | 11 +
drivers/iommu/Makefile | 1 +
drivers/iommu/virtio-iommu.c | 1171 +++++++++++++++++
drivers/pci/of.c | 14 +-
include/uapi/linux/virtio_ids.h | 1 +
include/uapi/linux/virtio_iommu.h | 159 +++
9 files changed, 1457 insertions(+), 3 deletions(-)
create mode 100644 Documentation/devicetree/bindings/virtio/iommu.txt
create mode 100644 drivers/iommu/virtio-iommu.c
create mode 100644 include/uapi/linux/virtio_iommu.h
--
2.19.1
