KVM: x86: consolidate different ways to test for in-kernel LAPIC

Different pieces of code checked for vcpu->arch.apic being (non-)NULL,
or used kvm_vcpu_has_lapic (more optimized) or lapic_in_kernel.
Replace everything with lapic_in_kernel's name and kvm_vcpu_has_lapic's
implementation.
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/irq.h

@@ -109,14 +109,6 @@ static inline int irqchip_in_kernel(struct kvm *kvm)
 	return ret;
 }
 
-static inline int lapic_in_kernel(struct kvm_vcpu *vcpu)
-{
-	/* Same as irqchip_in_kernel(vcpu->kvm), but with less
-	 * pointer chasing and no unnecessary memory barriers.
-	 */
-	return vcpu->arch.apic != NULL;
-}
-
 void kvm_pic_reset(struct kvm_kpic_state *s);
 
 void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu);

arch/x86/kvm/lapic.c

@@ -281,7 +281,7 @@ void kvm_apic_set_version(struct kvm_vcpu *vcpu)
 	struct kvm_cpuid_entry2 *feat;
 	u32 v = APIC_VERSION;
 
-	if (!kvm_vcpu_has_lapic(vcpu))
+	if (!lapic_in_kernel(vcpu))
 		return;
 
 	feat = kvm_find_cpuid_entry(apic->vcpu, 0x1, 0);
@@ -1319,7 +1319,7 @@ void wait_lapic_expire(struct kvm_vcpu *vcpu)
 	struct kvm_lapic *apic = vcpu->arch.apic;
 	u64 guest_tsc, tsc_deadline;
 
-	if (!kvm_vcpu_has_lapic(vcpu))
+	if (!lapic_in_kernel(vcpu))
 		return;
 
 	if (apic->lapic_timer.expired_tscdeadline == 0)
@@ -1645,7 +1645,7 @@ u64 kvm_get_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu)
 {
 	struct kvm_lapic *apic = vcpu->arch.apic;
 
-	if (!kvm_vcpu_has_lapic(vcpu) || apic_lvtt_oneshot(apic) ||
+	if (!lapic_in_kernel(vcpu) || apic_lvtt_oneshot(apic) ||
 			apic_lvtt_period(apic))
 		return 0;
 
@@ -1656,7 +1656,7 @@ void kvm_set_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu, u64 data)
 {
 	struct kvm_lapic *apic = vcpu->arch.apic;
 
-	if (!kvm_vcpu_has_lapic(vcpu) || apic_lvtt_oneshot(apic) ||
+	if (!lapic_in_kernel(vcpu) || apic_lvtt_oneshot(apic) ||
 			apic_lvtt_period(apic))
 		return;
 
@@ -2001,7 +2001,7 @@ void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
 {
 	struct hrtimer *timer;
 
-	if (!kvm_vcpu_has_lapic(vcpu))
+	if (!lapic_in_kernel(vcpu))
 		return;
 
 	timer = &vcpu->arch.apic->lapic_timer.timer;
@@ -2174,7 +2174,7 @@ int kvm_hv_vapic_msr_write(struct kvm_vcpu *vcpu, u32 reg, u64 data)
 {
 	struct kvm_lapic *apic = vcpu->arch.apic;
 
-	if (!kvm_vcpu_has_lapic(vcpu))
+	if (!lapic_in_kernel(vcpu))
 		return 1;
 
 	/* if this is ICR write vector before command */
@@ -2188,7 +2188,7 @@ int kvm_hv_vapic_msr_read(struct kvm_vcpu *vcpu, u32 reg, u64 *data)
 	struct kvm_lapic *apic = vcpu->arch.apic;
 	u32 low, high = 0;
 
-	if (!kvm_vcpu_has_lapic(vcpu))
+	if (!lapic_in_kernel(vcpu))
 		return 1;
 
 	if (apic_reg_read(apic, reg, 4, &low))
@@ -2220,7 +2220,7 @@ void kvm_apic_accept_events(struct kvm_vcpu *vcpu)
 	u8 sipi_vector;
 	unsigned long pe;
 
-	if (!kvm_vcpu_has_lapic(vcpu) || !apic->pending_events)
+	if (!lapic_in_kernel(vcpu) || !apic->pending_events)
 		return;
 
 	/*

arch/x86/kvm/lapic.h

@@ -103,7 +103,7 @@ static inline u32 kvm_apic_get_reg(struct kvm_lapic *apic, int reg_off)
 
 extern struct static_key kvm_no_apic_vcpu;
 
-static inline bool kvm_vcpu_has_lapic(struct kvm_vcpu *vcpu)
+static inline bool lapic_in_kernel(struct kvm_vcpu *vcpu)
 {
 	if (static_key_false(&kvm_no_apic_vcpu))
 		return vcpu->arch.apic;
@@ -130,7 +130,7 @@ static inline bool kvm_apic_sw_enabled(struct kvm_lapic *apic)
 
 static inline bool kvm_apic_present(struct kvm_vcpu *vcpu)
 {
-	return kvm_vcpu_has_lapic(vcpu) && kvm_apic_hw_enabled(vcpu->arch.apic);
+	return lapic_in_kernel(vcpu) && kvm_apic_hw_enabled(vcpu->arch.apic);
 }
 
 static inline int kvm_lapic_enabled(struct kvm_vcpu *vcpu)
@@ -150,7 +150,7 @@ static inline bool kvm_vcpu_apicv_active(struct kvm_vcpu *vcpu)
 
 static inline bool kvm_apic_has_events(struct kvm_vcpu *vcpu)
 {
-	return kvm_vcpu_has_lapic(vcpu) && vcpu->arch.apic->pending_events;
+	return lapic_in_kernel(vcpu) && vcpu->arch.apic->pending_events;
 }
 
 static inline bool kvm_lowest_prio_delivery(struct kvm_lapic_irq *irq)
@@ -161,7 +161,7 @@ static inline bool kvm_lowest_prio_delivery(struct kvm_lapic_irq *irq)
 
 static inline int kvm_lapic_latched_init(struct kvm_vcpu *vcpu)
 {
-	return kvm_vcpu_has_lapic(vcpu) && test_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
+	return lapic_in_kernel(vcpu) && test_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
 }
 
 static inline int kvm_apic_id(struct kvm_lapic *apic)

arch/x86/kvm/pmu.c

@@ -257,7 +257,7 @@ int kvm_pmu_rdpmc(struct kvm_vcpu *vcpu, unsigned idx, u64 *data)
 
 void kvm_pmu_deliver_pmi(struct kvm_vcpu *vcpu)
 {
-	if (vcpu->arch.apic)
+	if (lapic_in_kernel(vcpu))
 		kvm_apic_local_deliver(vcpu->arch.apic, APIC_LVTPC);
 }
 

arch/x86/kvm/x86.c

@@ -2984,7 +2984,7 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
 	kvm_x86_ops->set_nmi_mask(vcpu, events->nmi.masked);
 
 	if (events->flags & KVM_VCPUEVENT_VALID_SIPI_VECTOR &&
-	    kvm_vcpu_has_lapic(vcpu))
+	    lapic_in_kernel(vcpu))
 		vcpu->arch.apic->sipi_vector = events->sipi_vector;
 
 	if (events->flags & KVM_VCPUEVENT_VALID_SMM) {
@@ -2997,7 +2997,7 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
 			vcpu->arch.hflags |= HF_SMM_INSIDE_NMI_MASK;
 		else
 			vcpu->arch.hflags &= ~HF_SMM_INSIDE_NMI_MASK;
-		if (kvm_vcpu_has_lapic(vcpu)) {
+		if (lapic_in_kernel(vcpu)) {
 			if (events->smi.latched_init)
 				set_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
 			else
@@ -3237,7 +3237,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 	switch (ioctl) {
 	case KVM_GET_LAPIC: {
 		r = -EINVAL;
-		if (!vcpu->arch.apic)
+		if (!lapic_in_kernel(vcpu))
 			goto out;
 		u.lapic = kzalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL);
 
@@ -3255,7 +3255,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 	}
 	case KVM_SET_LAPIC: {
 		r = -EINVAL;
-		if (!vcpu->arch.apic)
+		if (!lapic_in_kernel(vcpu))
 			goto out;
 		u.lapic = memdup_user(argp, sizeof(*u.lapic));
 		if (IS_ERR(u.lapic))
@@ -4090,7 +4090,7 @@ static int vcpu_mmio_write(struct kvm_vcpu *vcpu, gpa_t addr, int len,
 
 	do {
 		n = min(len, 8);
-		if (!(vcpu->arch.apic &&
+		if (!(lapic_in_kernel(vcpu) &&
 		      !kvm_iodevice_write(vcpu, &vcpu->arch.apic->dev, addr, n, v))
 		    && kvm_io_bus_write(vcpu, KVM_MMIO_BUS, addr, n, v))
 			break;
@@ -4110,7 +4110,7 @@ static int vcpu_mmio_read(struct kvm_vcpu *vcpu, gpa_t addr, int len, void *v)
 
 	do {
 		n = min(len, 8);
-		if (!(vcpu->arch.apic &&
+		if (!(lapic_in_kernel(vcpu) &&
 		      !kvm_iodevice_read(vcpu, &vcpu->arch.apic->dev,
 					 addr, n, v))
 		    && kvm_io_bus_read(vcpu, KVM_MMIO_BUS, addr, n, v))
@@ -6007,7 +6007,7 @@ static void update_cr8_intercept(struct kvm_vcpu *vcpu)
 	if (!kvm_x86_ops->update_cr8_intercept)
 		return;
 
-	if (!vcpu->arch.apic)
+	if (!lapic_in_kernel(vcpu))
 		return;
 
 	if (vcpu->arch.apicv_active)
@@ -7035,7 +7035,7 @@ int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
 				    struct kvm_mp_state *mp_state)
 {
-	if (!kvm_vcpu_has_lapic(vcpu) &&
+	if (!lapic_in_kernel(vcpu) &&
 	    mp_state->mp_state != KVM_MP_STATE_RUNNABLE)
 		return -EINVAL;
 
@@ -7590,6 +7590,7 @@ bool kvm_vcpu_compatible(struct kvm_vcpu *vcpu)
 }
 
 struct static_key kvm_no_apic_vcpu __read_mostly;
+EXPORT_SYMBOL_GPL(kvm_no_apic_vcpu);
 
 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
 {