KVM: x86: Rename ->tlb_flush() to ->tlb_flush_all()

Rename ->tlb_flush() to ->tlb_flush_all() in preparation for adding a
new hook to flush only the current ASID/context.

Opportunstically replace the comment in vmx_flush_tlb() that explains
why it flushes all EPTP/VPID contexts with a comment explaining why it
unconditionally uses INVEPT when EPT is enabled.  I.e. rely on the "all"
part of the name to clarify why it does global INVEPT/INVVPID.

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200320212833.3507-23-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index daf1624..cd2a3d0 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2690,10 +2690,10 @@ static void kvmclock_reset(struct kvm_vcpu *vcpu)
 	vcpu->arch.time = 0;
 }
 
-static void kvm_vcpu_flush_tlb(struct kvm_vcpu *vcpu)
+static void kvm_vcpu_flush_tlb_all(struct kvm_vcpu *vcpu)
 {
 	++vcpu->stat.tlb_flush;
-	kvm_x86_ops.tlb_flush(vcpu);
+	kvm_x86_ops.tlb_flush_all(vcpu);
 }
 
 static void kvm_vcpu_flush_tlb_guest(struct kvm_vcpu *vcpu)
@@ -8223,7 +8223,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 		if (kvm_check_request(KVM_REQ_LOAD_MMU_PGD, vcpu))
 			kvm_mmu_load_pgd(vcpu);
 		if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu))
-			kvm_vcpu_flush_tlb(vcpu);
+			kvm_vcpu_flush_tlb_all(vcpu);
 		if (kvm_check_request(KVM_REQ_HV_TLB_FLUSH, vcpu))
 			kvm_vcpu_flush_tlb_guest(vcpu);
 		if (kvm_check_request(KVM_REQ_REPORT_TPR_ACCESS, vcpu)) {