[RFC PATCH v1 0/2] Define some VFIO interfaces for VT-d Posted-Interrupts

[Feng Wu <feng.wu@intel.com>]

VT-d Posted-Interrupts is an enhancement to CPU side Posted-Interrupt.
With VT-d Posted-Interrupts enabled, external interrupts from
direct-assigned devices can be delivered to guests without VMM
intervention when guest is running in non-root mode.

You can find the VT-d Posted-Interrtups Spec. in the following URL:
http://www.intel.com/content/www/us/en/intelligent-systems/intel-technology/vt-directed-io-spec.html

This patch set does the following things:

- Define a new VFIO group KVM_DEV_VFIO_INTERRUPT and it's attributes
KVM_DEV_VFIO_INTERRUPT_POSTING_IRQ. Qemu can use this interface to
configure VT-d PI when guest updates the interrupt configuration
(MSI/MSI-X configuration).

- Define a new VFIO API: vfio_msi_get_irq(), which can be used by KVM
to get the host irq of the assigned devices. Then KVM can update the
associated IRTE for VT-d PI.

Feng Wu (2):
  vfio: Add new interrupt group for VFIO
  vfio: Add VFIO API vfio_msi_get_irq

 Documentation/virtual/kvm/devices/vfio.txt |    8 ++++++++
 drivers/vfio/pci/vfio_pci.c                |   10 ++++++++++
 include/linux/vfio.h                       |    2 ++
 include/uapi/linux/kvm.h                   |   14 ++++++++++++++
 4 files changed, 34 insertions(+), 0 deletions(-)