sys/linux: declare KVM_{SET,GET,HAS}_DEVICE_ATTR for VMs

In addition to device FDs, certain arches (s390 and ARM64) allow applying
device attributes to VM FDs (https://docs.kernel.org/virt/kvm/devices/vm.html)
Add descriptions for the corresponding ioctls on ARM64, including support
for setting SMCCC filters via struct kvm_smccc_filter.

1 files changed, 33 insertions, 0 deletions

diff --git a/sys/linux/dev_kvm.txt b/sys/linux/dev_kvm.txt
index 16434a1d0..2066b8d78 100644
--- a/sys/linux/dev_kvm.txt
+++ b/sys/linux/dev_kvm.txt
@@ -147,6 +147,13 @@ ioctl$KVM_SET_DEVICE_ATTR(fd fd_kvmdev, cmd const[KVM_SET_DEVICE_ATTR], arg ptr[
 ioctl$KVM_GET_DEVICE_ATTR(fd fd_kvmdev, cmd const[KVM_GET_DEVICE_ATTR], arg ptr[in, kvm_device_attr])
 ioctl$KVM_HAS_DEVICE_ATTR(fd fd_kvmdev, cmd const[KVM_HAS_DEVICE_ATTR], arg ptr[in, kvm_device_attr])
 
+# From https://docs.kernel.org/virt/kvm/devices/vm.html:
+# The virtual machine “device” also accepts the ioctls KVM_SET_DEVICE_ATTR, KVM_GET_DEVICE_ATTR, and KVM_HAS_DEVICE_ATTR.
+# The interface uses the same struct kvm_device_attr as other devices, but targets VM-wide settings and controls.
+ioctl$KVM_SET_DEVICE_ATTR_vm(fd fd_kvmvm, cmd const[KVM_SET_DEVICE_ATTR], arg ptr[in, kvm_device_attr_vm])
+ioctl$KVM_GET_DEVICE_ATTR_vm(fd fd_kvmvm, cmd const[KVM_GET_DEVICE_ATTR], arg ptr[in, kvm_device_attr_vm])
+ioctl$KVM_HAS_DEVICE_ATTR_vm(fd fd_kvmvm, cmd const[KVM_HAS_DEVICE_ATTR], arg ptr[in, kvm_device_attr_vm])
+
 kvm_mem_region_flags = KVM_MEM_LOG_DIRTY_PAGES, KVM_MEM_READONLY
 kvm_mp_state = KVM_MP_STATE_RUNNABLE, KVM_MP_STATE_UNINITIALIZED, KVM_MP_STATE_INIT_RECEIVED, KVM_MP_STATE_HALTED, KVM_MP_STATE_SIPI_RECEIVED, KVM_MP_STATE_STOPPED, KVM_MP_STATE_CHECK_STOP, KVM_MP_STATE_OPERATING, KVM_MP_STATE_LOAD
 kvm_irq_routing_entry_type = KVM_IRQ_ROUTING_IRQCHIP, KVM_IRQ_ROUTING_MSI, KVM_IRQ_ROUTING_S390_ADAPTER, KVM_IRQ_ROUTING_HV_SINT
@@ -406,6 +413,32 @@ kvm_device_attr {
 	addr	ptr64[in, int64]
 }
 
+kvm_device_attr_vm [
+	attr_arm64	kvm_device_attr_vm_arm64
+	attr_other	kvm_device_attr
+]
+
+kvm_vm_attr_group_arm64 = KVM_ARM_VM_SMCCC_CTRL
+kvm_vm_attr_attr_arm64 = KVM_ARM_VM_SMCCC_FILTER
+
+# TODO(glider): as of now the only supported argument is kvm_smccc_filter.
+# Need to make addr point to a union when this changes.
+kvm_device_attr_vm_arm64 {
+	flags	const[0, int32]
+	group	flags[kvm_vm_attr_group_arm64, int32]
+	attr	flags[kvm_vm_attr_attr_arm64, int64]
+	addr	ptr64[in, kvm_smccc_filter]
+}
+
+kvm_smccc_filter_action = KVM_SMCCC_FILTER_HANDLE, KVM_SMCCC_FILTER_DENY, KVM_SMCCC_FILTER_FWD_TO_USER
+
+kvm_smccc_filter {
+	base		int32
+	nr_functions	int32
+	action		flags[kvm_smccc_filter_action, int8]
+	pad		array[const[0, int8], 15]
+}
+
 kvm_create_device {
 	type	flags[kvm_device_type, int32]	(in)
 	fd	fd_kvmdev	(out)