KVM: arm64: timers: Rationalise per-vcpu timer init

The way we initialise our timer contexts may be satisfactory
for two timers, but will be getting pretty annoying with four.

Cleanup the whole thing by removing the code duplication and
getting rid of unused IRQ configuration elements.

Reviewed-by: Colton Lewis <coltonlewis@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230330174800.2677007-10-maz@kernel.org

2 files changed, 39 insertions, 35 deletions

diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c
index 771504c79711..e46f04ed8f86 100644
--- a/arch/arm64/kvm/arch_timer.c
+++ b/arch/arm64/kvm/arch_timer.c
@@ -30,14 +30,9 @@ static u32 host_ptimer_irq_flags;
 
 static DEFINE_STATIC_KEY_FALSE(has_gic_active_state);
 
-static const struct kvm_irq_level default_ptimer_irq = {
-	.irq	= 30,
-	.level	= 1,
-};
-
-static const struct kvm_irq_level default_vtimer_irq = {
-	.irq	= 27,
-	.level	= 1,
+static const u8 default_ppi[] = {
+	[TIMER_PTIMER]  = 30,
+	[TIMER_VTIMER]  = 27,
 };
 
 static bool kvm_timer_irq_can_fire(struct arch_timer_context *timer_ctx);
@@ -820,12 +815,14 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu)
 	 * resets the timer to be disabled and unmasked and is compliant with
 	 * the ARMv7 architecture.
 	 */
-	timer_set_ctl(vcpu_vtimer(vcpu), 0);
-	timer_set_ctl(vcpu_ptimer(vcpu), 0);
+	for (int i = 0; i < NR_KVM_TIMERS; i++)
+		timer_set_ctl(vcpu_get_timer(vcpu, i), 0);
+
 
 	if (timer->enabled) {
-		kvm_timer_update_irq(vcpu, false, vcpu_vtimer(vcpu));
-		kvm_timer_update_irq(vcpu, false, vcpu_ptimer(vcpu));
+		for (int i = 0; i < NR_KVM_TIMERS; i++)
+			kvm_timer_update_irq(vcpu, false,
+					     vcpu_get_timer(vcpu, i));
 
 		if (irqchip_in_kernel(vcpu->kvm)) {
 			kvm_vgic_reset_mapped_irq(vcpu, map.direct_vtimer->irq.irq);
@@ -840,39 +837,47 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu)
 	return 0;
 }
 
+static void timer_context_init(struct kvm_vcpu *vcpu, int timerid)
+{
+	struct arch_timer_context *ctxt = vcpu_get_timer(vcpu, timerid);
+	struct kvm *kvm = vcpu->kvm;
+
+	ctxt->vcpu = vcpu;
+
+	if (timerid == TIMER_VTIMER)
+		ctxt->offset.vm_offset = &kvm->arch.timer_data.voffset;
+	else
+		ctxt->offset.vm_offset = &kvm->arch.timer_data.poffset;
+
+	hrtimer_init(&ctxt->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
+	ctxt->hrtimer.function = kvm_hrtimer_expire;
+	ctxt->irq.irq = default_ppi[timerid];
+
+	switch (timerid) {
+	case TIMER_PTIMER:
+		ctxt->host_timer_irq = host_ptimer_irq;
+		break;
+	case TIMER_VTIMER:
+		ctxt->host_timer_irq = host_vtimer_irq;
+		break;
+	}
+}
+
 void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
 {
 	struct arch_timer_cpu *timer = vcpu_timer(vcpu);
-	struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
-	struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
 
-	vtimer->vcpu = vcpu;
-	vtimer->offset.vm_offset = &vcpu->kvm->arch.timer_data.voffset;
-	ptimer->vcpu = vcpu;
-	ptimer->offset.vm_offset = &vcpu->kvm->arch.timer_data.poffset;
+	for (int i = 0; i < NR_KVM_TIMERS; i++)
+		timer_context_init(vcpu, i);
 
 	/* Synchronize offsets across timers of a VM if not already provided */
 	if (!test_bit(KVM_ARCH_FLAG_VM_COUNTER_OFFSET, &vcpu->kvm->arch.flags)) {
-		timer_set_offset(vtimer, kvm_phys_timer_read());
-		timer_set_offset(ptimer, 0);
+		timer_set_offset(vcpu_vtimer(vcpu), kvm_phys_timer_read());
+		timer_set_offset(vcpu_ptimer(vcpu), 0);
 	}
 
 	hrtimer_init(&timer->bg_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
 	timer->bg_timer.function = kvm_bg_timer_expire;
-
-	hrtimer_init(&vtimer->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
-	hrtimer_init(&ptimer->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
-	vtimer->hrtimer.function = kvm_hrtimer_expire;
-	ptimer->hrtimer.function = kvm_hrtimer_expire;
-
-	vtimer->irq.irq = default_vtimer_irq.irq;
-	ptimer->irq.irq = default_ptimer_irq.irq;
-
-	vtimer->host_timer_irq = host_vtimer_irq;
-	ptimer->host_timer_irq = host_ptimer_irq;
-
-	vtimer->host_timer_irq_flags = host_vtimer_irq_flags;
-	ptimer->host_timer_irq_flags = host_ptimer_irq_flags;
 }
 
 void kvm_timer_cpu_up(void)
diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h
index 2dd0fd2406fb..c746ef64220b 100644
--- a/include/kvm/arm_arch_timer.h
+++ b/include/kvm/arm_arch_timer.h
@@ -59,7 +59,6 @@ struct arch_timer_context {
 
 	/* Duplicated state from arch_timer.c for convenience */
 	u32				host_timer_irq;
-	u32				host_timer_irq_flags;
 };
 
 struct timer_map {