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+ARM Virtual Interrupt Translation Service (ITS)
+===============================================
+
+Device types supported:
+ KVM_DEV_TYPE_ARM_VGIC_ITS ARM Interrupt Translation Service Controller
+
+The ITS allows MSI(-X) interrupts to be injected into guests. This extension is
+optional. Creating a virtual ITS controller also requires a host GICv3 (see
+arm-vgic-v3.txt), but does not depend on having physical ITS controllers.
+
+There can be multiple ITS controllers per guest, each of them has to have
+a separate, non-overlapping MMIO region.
+
+
+Groups:
+ KVM_DEV_ARM_VGIC_GRP_ADDR
+ Attributes:
+ KVM_VGIC_ITS_ADDR_TYPE (rw, 64-bit)
+ Base address in the guest physical address space of the GICv3 ITS
+ control register frame.
+ This address needs to be 64K aligned and the region covers 128K.
+ Errors:
+ -E2BIG: Address outside of addressable IPA range
+ -EINVAL: Incorrectly aligned address
+ -EEXIST: Address already configured
+ -EFAULT: Invalid user pointer for attr->addr.
+ -ENODEV: Incorrect attribute or the ITS is not supported.
+
+
+ KVM_DEV_ARM_VGIC_GRP_CTRL
+ Attributes:
+ KVM_DEV_ARM_VGIC_CTRL_INIT
+ request the initialization of the ITS, no additional parameter in
+ kvm_device_attr.addr.
+ Errors:
+ -ENXIO: ITS not properly configured as required prior to setting
+ this attribute
+ -ENOMEM: Memory shortage when allocating ITS internal data