[PATCH 2/7] KVM: SVM: extract load_nested_vmcb_control

[Paolo Bonzini]

When restoring SVM nested state, the control state will be stored already
in svm->nested by KVM_SET_NESTED_STATE.  We will not need to fish it out of
L1's VMCB.  Pull everything into a separate function so that it is
documented which fields are needed.

Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
 arch/x86/kvm/svm/nested.c | 45 ++++++++++++++++++++++-----------------
 1 file changed, 25 insertions(+), 20 deletions(-)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 22f75f66084f..e79acc852000 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -225,6 +225,27 @@ static bool nested_vmcb_checks(struct vmcb *vmcb)
 	return true;
 }
 
+static void load_nested_vmcb_control(struct vcpu_svm *svm, struct vmcb *nested_vmcb)
+{
+	if (kvm_get_rflags(&svm->vcpu) & X86_EFLAGS_IF)
+		svm->vcpu.arch.hflags |= HF_HIF_MASK;
+	else
+		svm->vcpu.arch.hflags &= ~HF_HIF_MASK;
+
+	svm->nested.nested_cr3 = nested_vmcb->control.nested_cr3;
+
+	svm->nested.vmcb_msrpm = nested_vmcb->control.msrpm_base_pa & ~0x0fffULL;
+	svm->nested.vmcb_iopm  = nested_vmcb->control.iopm_base_pa  & ~0x0fffULL;
+
+	/* cache intercepts */
+	svm->nested.intercept_cr         = nested_vmcb->control.intercept_cr;
+	svm->nested.intercept_dr         = nested_vmcb->control.intercept_dr;
+	svm->nested.intercept_exceptions = nested_vmcb->control.intercept_exceptions;
+	svm->nested.intercept            = nested_vmcb->control.intercept;
+
+	svm->vcpu.arch.tsc_offset += nested_vmcb->control.tsc_offset;
+}
+
 void enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb_gpa,
 			  struct vmcb *nested_vmcb)
 {
@@ -232,15 +253,11 @@ void enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb_gpa,
 		is_intercept(svm, INTERCEPT_VINTR) ||
 		is_intercept(svm, INTERCEPT_IRET);
 
-	if (kvm_get_rflags(&svm->vcpu) & X86_EFLAGS_IF)
-		svm->vcpu.arch.hflags |= HF_HIF_MASK;
-	else
-		svm->vcpu.arch.hflags &= ~HF_HIF_MASK;
+	svm->nested.vmcb = vmcb_gpa;
+	load_nested_vmcb_control(svm, nested_vmcb);
 
-	if (nested_vmcb->control.nested_ctl & SVM_NESTED_CTL_NP_ENABLE) {
-		svm->nested.nested_cr3 = nested_vmcb->control.nested_cr3;
+	if (nested_vmcb->control.nested_ctl & SVM_NESTED_CTL_NP_ENABLE)
 		nested_svm_init_mmu_context(&svm->vcpu);
-	}
 
 	/* Load the nested guest state */
 	svm->vmcb->save.es = nested_vmcb->save.es;
@@ -275,25 +292,15 @@ void enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb_gpa,
 	svm->vcpu.arch.dr6  = nested_vmcb->save.dr6;
 	svm->vmcb->save.cpl = nested_vmcb->save.cpl;
 
-	svm->nested.vmcb_msrpm = nested_vmcb->control.msrpm_base_pa & ~0x0fffULL;
-	svm->nested.vmcb_iopm  = nested_vmcb->control.iopm_base_pa  & ~0x0fffULL;
-
-	/* cache intercepts */
-	svm->nested.intercept_cr         = nested_vmcb->control.intercept_cr;
-	svm->nested.intercept_dr         = nested_vmcb->control.intercept_dr;
-	svm->nested.intercept_exceptions = nested_vmcb->control.intercept_exceptions;
-	svm->nested.intercept            = nested_vmcb->control.intercept;
-
 	svm_flush_tlb(&svm->vcpu);
-	svm->vmcb->control.int_ctl = nested_vmcb->control.int_ctl | V_INTR_MASKING_MASK;
 	if (nested_vmcb->control.int_ctl & V_INTR_MASKING_MASK)
 		svm->vcpu.arch.hflags |= HF_VINTR_MASK;
 	else
 		svm->vcpu.arch.hflags &= ~HF_VINTR_MASK;
 
-	svm->vcpu.arch.tsc_offset += nested_vmcb->control.tsc_offset;
 	svm->vmcb->control.tsc_offset = svm->vcpu.arch.tsc_offset;
 
+	svm->vmcb->control.int_ctl = nested_vmcb->control.int_ctl | V_INTR_MASKING_MASK;
 	svm->vmcb->control.virt_ext = nested_vmcb->control.virt_ext;
 	svm->vmcb->control.int_vector = nested_vmcb->control.int_vector;
 	svm->vmcb->control.int_state = nested_vmcb->control.int_state;
@@ -314,8 +321,6 @@ void enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb_gpa,
 	 */
 	recalc_intercepts(svm);
 
-	svm->nested.vmcb = vmcb_gpa;
-
 	/*
 	 * If L1 had a pending IRQ/NMI before executing VMRUN,
 	 * which wasn't delivered because it was disallowed (e.g.
-- 
2.18.2