[RFC PATCH v1 1/2] vfio: Add new interrupt group for VFIO

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

Add new group KVM_DEV_VFIO_INTERRUPT and command
KVM_DEV_VFIO_DEVIE_POSTING_IRQ related to it.

This is used for VT-d Posted-Interrupts setup.

Signed-off-by: Feng Wu <feng.wu@intel.com>
---
 Documentation/virtual/kvm/devices/vfio.txt |    8 ++++++++
 include/uapi/linux/kvm.h                   |   14 ++++++++++++++
 2 files changed, 22 insertions(+), 0 deletions(-)

diff --git a/Documentation/virtual/kvm/devices/vfio.txt b/Documentation/virtual/kvm/devices/vfio.txt
index ef51740..bd99176 100644
--- a/Documentation/virtual/kvm/devices/vfio.txt
+++ b/Documentation/virtual/kvm/devices/vfio.txt
@@ -13,6 +13,7 @@ VFIO-group is held by KVM.
 
 Groups:
   KVM_DEV_VFIO_GROUP
+  KVM_DEV_VFIO_INTERRUPT
 
 KVM_DEV_VFIO_GROUP attributes:
   KVM_DEV_VFIO_GROUP_ADD: Add a VFIO group to VFIO-KVM device tracking
@@ -20,3 +21,10 @@ KVM_DEV_VFIO_GROUP attributes:
 
 For each, kvm_device_attr.addr points to an int32_t file descriptor
 for the VFIO group.
+
+KVM_DEV_VFIO_INTERRUPT attributes:
+  KVM_DEV_VFIO_INTERRUPT_POSTING_IRQ: Set up the interrupt configuration for
+VT-d Posted-Interrrupts
+
+For each, kvm_device_attr.addr points to struct kvm_posted_intr, which
+include the needed information for VT-d Posted-Interrupts setup.
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 6076882..5544fcc 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -943,9 +943,23 @@ struct kvm_device_attr {
 	__u64	addr;		/* userspace address of attr data */
 };
 
+struct virq_info {
+	__u32	index;		/* index of the msi/msix entry */
+	int	virq;		/* virq of the interrupt */
+};
+
+struct kvm_posted_intr {
+	__u32	fd;		/* file descriptor of the VFIO device */
+	__u32	count;
+	bool	msix;
+	struct virq_info virq_info[0];
+};
+
 #define  KVM_DEV_VFIO_GROUP			1
 #define   KVM_DEV_VFIO_GROUP_ADD			1
 #define   KVM_DEV_VFIO_GROUP_DEL			2
+#define  KVM_DEV_VFIO_INTERRUPT			2
+#define   KVM_DEV_VFIO_INTERRUPT_POSTING_IRQ		1
 
 enum kvm_device_type {
 	KVM_DEV_TYPE_FSL_MPIC_20	= 1,
-- 
1.7.1