These two patches together implements a PCIe capability config space header for Access Control Services (ACS) for the new Qemu specific generic root port. ACS support in the associated root port is a prerequisite to be able to pass individual functions of a device populating the port through to an L2 guest from an unmodified kernel.
Without this, the IOMMU group the device belongs to will also include the root port itself, and all functions the device provides. It is necessary to support SR/IOV where the primary purpose is to be able to share out individual VFs to different guests, which will not be permitted by VFIO or the Windows Hyper-V equivalent unless ACS is supported by the root port. These patches can also be found as part of an updated version of my SR/IOV emulation patch set at https://github.com/knuto/qemu/tree/sriov_patches_v11 The patches' basic operation with VFIO and iommu groups have been tested with the above patch set and a rebased version of an in progress igb ethernet device, which needs some more care before I can let it go out. Changes from v2: ---------------- - rebased to the latest qemu master Incorporated further feedback from Alex: - Make sure slot/downstream capability bits are only set for slots. - Make acs reset callback do nothing if no acs capability exists - Set correct acs version - div simplification Changes from v1: ---------------- Incorporated feedback from Alex Williamson: - Make commit messages reflect a more correct understanding of how this affects VFIO operation. - Implemented the CTRL register properly (reset callback + making non-implemented capabilities RO, default value 0) - removed the egress ctrl vector parameter to the init function - Fixed some whitespace issues Knut Omang (2): pcie: Add a simple PCIe ACS (Access Control Services) helper function gen_pcie_root_port: Add ACS (Access Control Services) capability hw/pci-bridge/gen_pcie_root_port.c | 4 ++++ hw/pci-bridge/pcie_root_port.c | 4 ++++ hw/pci/pcie.c | 29 +++++++++++++++++++++++++++++ include/hw/pci/pcie.h | 6 ++++++ include/hw/pci/pcie_port.h | 1 + include/hw/pci/pcie_regs.h | 4 ++++ 6 files changed, 48 insertions(+) base-commit: e47f81b617684c4546af286d307b69014a83538a -- git-series 0.9.1
