KVM: arm64: timers: Allow save/restoring of the physical timer

Nothing like being 10 year late to a party!

Now that userspace can set counter offsets, we can save/restore
the physical timer as well!

Nobody really cared so far, but you're welcome anyway.
Reviewed-by: Colton Lewis <coltonlewis@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230330174800.2677007-9-maz@kernel.org

arch/arm64/kvm/guest.c

@@ -590,11 +590,16 @@ static unsigned long num_core_regs(const struct kvm_vcpu *vcpu)
 	return copy_core_reg_indices(vcpu, NULL);
 }
 
-/**
- * ARM64 versions of the TIMER registers, always available on arm64
- */
+static const u64 timer_reg_list[] = {
+	KVM_REG_ARM_TIMER_CTL,
+	KVM_REG_ARM_TIMER_CNT,
+	KVM_REG_ARM_TIMER_CVAL,
+	KVM_REG_ARM_PTIMER_CTL,
+	KVM_REG_ARM_PTIMER_CNT,
+	KVM_REG_ARM_PTIMER_CVAL,
+};
 
-#define NUM_TIMER_REGS 3
+#define NUM_TIMER_REGS ARRAY_SIZE(timer_reg_list)
 
 static bool is_timer_reg(u64 index)
 {
@@ -602,6 +607,9 @@ static bool is_timer_reg(u64 index)
 	case KVM_REG_ARM_TIMER_CTL:
 	case KVM_REG_ARM_TIMER_CNT:
 	case KVM_REG_ARM_TIMER_CVAL:
+	case KVM_REG_ARM_PTIMER_CTL:
+	case KVM_REG_ARM_PTIMER_CNT:
+	case KVM_REG_ARM_PTIMER_CVAL:
 		return true;
 	}
 	return false;
@@ -609,14 +617,11 @@ static bool is_timer_reg(u64 index)
 
 static int copy_timer_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 {
-	if (put_user(KVM_REG_ARM_TIMER_CTL, uindices))
-		return -EFAULT;
-	uindices++;
-	if (put_user(KVM_REG_ARM_TIMER_CNT, uindices))
-		return -EFAULT;
-	uindices++;
-	if (put_user(KVM_REG_ARM_TIMER_CVAL, uindices))
-		return -EFAULT;
+	for (int i = 0; i < NUM_TIMER_REGS; i++) {
+		if (put_user(timer_reg_list[i], uindices))
+			return -EFAULT;
+		uindices++;
+	}
 
 	return 0;
 }