[PATCH 4/6] KVM: nVMX: Use CLASS(kvm_vcpu_map_local_readonly) for MSR bitmap merging

[Sean Christopherson <seanjc@google.com>]

Convert the kvm_vcpu_map_readonly() usage in nVMX's MSR bitmap merging to
the new CLASS(kvm_vcpu_map_local_readonly) implementation, to eliminate the
last of the open-coded on-stack "struct kvm_host_map" declarations (in x86,
PPC still has one more to convert).

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/vmx/nested.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index f2518d67e7de..ef79769c6287 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -730,7 +730,6 @@ static inline bool nested_vmx_prepare_msr_bitmap(struct kvm_vcpu *vcpu,
 	int msr;
 	unsigned long *msr_bitmap_l1;
 	unsigned long *msr_bitmap_l0 = vmx->nested.vmcs02.msr_bitmap;
-	struct kvm_host_map map;
 
 	/* Nothing to do if the MSR bitmap is not in use.  */
 	if (!cpu_has_vmx_msr_bitmap() ||
@@ -753,10 +752,11 @@ static inline bool nested_vmx_prepare_msr_bitmap(struct kvm_vcpu *vcpu,
 			return true;
 	}
 
-	if (kvm_vcpu_map_readonly(vcpu, gpa_to_gfn(vmcs12->msr_bitmap), &map))
+	CLASS(kvm_vcpu_map_local_readonly, m)(vcpu, gpa_to_gfn(vmcs12->msr_bitmap));
+	if (m.ret)
 		return false;
 
-	msr_bitmap_l1 = (unsigned long *)map.hva;
+	msr_bitmap_l1 = (unsigned long *)m.map.hva;
 
 	/*
 	 * To keep the control flow simple, pay eight 8-byte writes (sixteen
@@ -836,8 +836,6 @@ static inline bool nested_vmx_prepare_msr_bitmap(struct kvm_vcpu *vcpu,
 
 	nested_vmx_merge_pmu_msr_bitmaps(vcpu, msr_bitmap_l1, msr_bitmap_l0);
 
-	kvm_vcpu_unmap(vcpu, &map);
-
 	vmx->nested.force_msr_bitmap_recalc = false;
 
 	return true;
-- 
2.55.0.229.g6434b31f56-goog