hypervisor: kvm: Implement vCPU state method

Implement the vCPU state getter and setter separately from the initial
KVM Hypervisor trait implementation, mostly for readability purposes.

Signed-off-by: Muminul Islam <muislam@microsoft.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

hypervisor/src/kvm/x86_64/mod.rs

@@ -10,19 +10,66 @@
 
 use vm_memory::GuestAddress;
 
+use crate::arch::x86::{msr_index, MTRR_ENABLE, MTRR_MEM_TYPE_WB};
 use crate::kvm::{Cap, Kvm, KvmError, KvmResult};
+use serde_derive::{Deserialize, Serialize};
 
+///
+/// Export generically-named wrappers of kvm-bindings for Unix-based platforms
+///
 ///
 /// Export generically-named wrappers of kvm-bindings for Unix-based platforms
 ///
 pub use {
-    kvm_bindings::kvm_lapic_state as LapicState,
+    kvm_bindings::kvm_dtable as DescriptorTable, kvm_bindings::kvm_fpu as FpuState,
+    kvm_bindings::kvm_lapic_state as LapicState, kvm_bindings::kvm_mp_state as MpState,
+    kvm_bindings::kvm_msr_entry as MsrEntry, kvm_bindings::kvm_regs as StandardRegisters,
+    kvm_bindings::kvm_segment as SegmentRegister, kvm_bindings::kvm_sregs as SpecialRegisters,
+    kvm_bindings::kvm_vcpu_events as VcpuEvents,
     kvm_bindings::kvm_xcrs as ExtendedControlRegisters, kvm_bindings::kvm_xsave as Xsave,
     kvm_bindings::CpuId, kvm_bindings::Msrs as MsrEntries,
 };
 
 pub const KVM_TSS_ADDRESS: GuestAddress = GuestAddress(0xfffb_d000);
 
+macro_rules! msr {
+    ($msr:expr) => {
+        MsrEntry {
+            index: $msr,
+            data: 0x0,
+            ..Default::default()
+        }
+    };
+}
+macro_rules! msr_data {
+    ($msr:expr, $data:expr) => {
+        MsrEntry {
+            index: $msr,
+            data: $data,
+            ..Default::default()
+        }
+    };
+}
+
+pub fn boot_msr_entries() -> MsrEntries {
+    MsrEntries::from_entries(&[
+        msr!(msr_index::MSR_IA32_SYSENTER_CS),
+        msr!(msr_index::MSR_IA32_SYSENTER_ESP),
+        msr!(msr_index::MSR_IA32_SYSENTER_EIP),
+        msr!(msr_index::MSR_STAR),
+        msr!(msr_index::MSR_CSTAR),
+        msr!(msr_index::MSR_LSTAR),
+        msr!(msr_index::MSR_KERNEL_GS_BASE),
+        msr!(msr_index::MSR_SYSCALL_MASK),
+        msr!(msr_index::MSR_IA32_TSC),
+        msr_data!(
+            msr_index::MSR_IA32_MISC_ENABLE,
+            msr_index::MSR_IA32_MISC_ENABLE_FAST_STRING as u64
+        ),
+        msr_data!(msr_index::MSR_MTRRdefType, MTRR_ENABLE | MTRR_MEM_TYPE_WB),
+    ])
+}
+
 ///
 /// Check KVM extension for Linux
 ///
@@ -38,3 +85,15 @@ pub fn check_required_kvm_extensions(kvm: &Kvm) -> KvmResult<()> {
     }
     Ok(())
 }
+#[derive(Clone, Serialize, Deserialize)]
+pub struct VcpuKvmState {
+    pub msrs: MsrEntries,
+    pub vcpu_events: VcpuEvents,
+    pub regs: StandardRegisters,
+    pub sregs: SpecialRegisters,
+    pub fpu: FpuState,
+    pub lapic_state: LapicState,
+    pub xsave: Xsave,
+    pub xcrs: ExtendedControlRegisters,
+    pub mp_state: MpState,
+}