[v4 00/16] Add VT-d Posted-Interrupts support

[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 series was part of http://thread.gmane.org/gmane.linux.kernel.iommu/7708. To make things clear, send out IOMMU part here.

This patch-set is based on the lastest x86/apic branch of tip tree.

Divide the whole series which contain multiple components into three parts:
- Prerequisite changes to irq subsystem (already merged in tip/x86/apic)
- IOMMU part (about to be merged in merged in tip/x86/apic), here is the
  latest version: https://lkml.org/lkml/2015/6/9/22
- KVM and VFIO parts (this series)

Patch 8, 9, and 10 are from Eric Auger, there are some common VFIO APIs
defined in them. I integrate them in this series and use the APIs in
my patches.

v4:
* For lowest-priority interrupt, only support single-CPU destination
interrupts at the current stage, more common lowest priority support
will be added later.
* Accoring to Marcelo's suggestion, when vCPU is blocked, we handle
the posted-interrupts in the HLT emulation path.
* Some small changes (coding style, typo, add some code comments)

Eric Auger (3):
  KVM: kvm-vfio: User API for IRQ forwarding
  VFIO: external user API for interaction
  KVM: kvm-vfio: wrappers to VFIO external API device helpers

Feng Wu (13):
  KVM: Extend struct pi_desc for VT-d Posted-Interrupts
  KVM: Add some helper functions for Posted-Interrupts
  KVM: Define a new interface kvm_intr_is_single_vcpu()
  KVM: Get Posted-Interrupts descriptor address from struct kvm_vcpu
  KVM: Add interfaces to control PI outside vmx
  KVM: Make struct kvm_irq_routing_table accessible
  KVM: make kvm_set_msi_irq() public
  KVM: kvm-vfio: User API for VT-d Posted-Interrupts
  KVM: kvm-vfio: implement the VFIO skeleton for VT-d Posted-Interrupts
  KVM: x86: kvm-vfio: VT-d posted-interrupts setup
  KVM: Update Posted-Interrupts Descriptor when vCPU is preempted
  KVM: Update Posted-Interrupts Descriptor when vCPU is blocked
  KVM: Warn if 'SN' is set during posting interrupts by software

 Documentation/virtual/kvm/devices/vfio.txt |  43 ++++-
 arch/x86/include/asm/kvm_host.h            |  16 ++
 arch/x86/kvm/Makefile                      |   3 +-
 arch/x86/kvm/irq_comm.c                    |  28 ++-
 arch/x86/kvm/kvm_vfio_x86.c                |  85 +++++++++
 arch/x86/kvm/vmx.c                         | 278 ++++++++++++++++++++++++++++-
 arch/x86/kvm/x86.c                         |  42 +++--
 drivers/vfio/vfio.c                        |  24 +++
 include/linux/kvm_host.h                   |  40 +++++
 include/linux/vfio.h                       |   3 +
 include/uapi/linux/kvm.h                   |  14 ++
 virt/kvm/irqchip.c                         |  11 --
 virt/kvm/kvm_main.c                        |   3 +
 virt/kvm/vfio.c                            | 200 +++++++++++++++++++++
 14 files changed, 758 insertions(+), 32 deletions(-)
 create mode 100644 arch/x86/kvm/kvm_vfio_x86.c

-- 
2.1.0