KVM: arm64: Repaint pmcr_n into nr_pmu_counters

The pmcr_n field obviously refers to PMCR_EL0.N, but is generally used
as the number of counters seen by the guest. Rename it accordingly.

Suggested-by: Oliver upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>

Author: Marc Zyngier

arch/arm64/include/asm/kvm_host.h

@@ -359,8 +359,8 @@ struct kvm_arch {
 
 	cpumask_var_t supported_cpus;
 
-	/* PMCR_EL0.N value for the guest */
-	u8 pmcr_n;
+	/* Maximum number of counters for the guest */
+	u8 nr_pmu_counters;
 
 	/* Iterator for idreg debugfs */
 	u8	idreg_debugfs_iter;

arch/arm64/kvm/pmu-emul.c

@@ -280,7 +280,7 @@ static u64 kvm_pmu_hyp_counter_mask(struct kvm_vcpu *vcpu)
 		return 0;
 
 	hpmn = SYS_FIELD_GET(MDCR_EL2, HPMN, __vcpu_sys_reg(vcpu, MDCR_EL2));
-	n = vcpu->kvm->arch.pmcr_n;
+	n = vcpu->kvm->arch.nr_pmu_counters;
 
 	/*
 	 * Programming HPMN to a value greater than PMCR_EL0.N is
@@ -1032,7 +1032,7 @@ static void kvm_arm_set_pmu(struct kvm *kvm, struct arm_pmu *arm_pmu)
 	lockdep_assert_held(&kvm->arch.config_lock);
 
 	kvm->arch.arm_pmu = arm_pmu;
-	kvm->arch.pmcr_n = kvm_arm_pmu_get_max_counters(kvm);
+	kvm->arch.nr_pmu_counters = kvm_arm_pmu_get_max_counters(kvm);
 }
 
 /**
@@ -1261,7 +1261,7 @@ u64 kvm_vcpu_read_pmcr(struct kvm_vcpu *vcpu)
 {
 	u64 pmcr = __vcpu_sys_reg(vcpu, PMCR_EL0);
 
-	return u64_replace_bits(pmcr, vcpu->kvm->arch.pmcr_n, ARMV8_PMU_PMCR_N);
+	return u64_replace_bits(pmcr, vcpu->kvm->arch.nr_pmu_counters, ARMV8_PMU_PMCR_N);
 }
 
 void kvm_pmu_nested_transition(struct kvm_vcpu *vcpu)

arch/arm64/kvm/sys_regs.c

@@ -785,7 +785,7 @@ static unsigned int pmu_visibility(const struct kvm_vcpu *vcpu,
 static u64 reset_pmu_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
 {
 	u64 mask = BIT(ARMV8_PMU_CYCLE_IDX);
-	u8 n = vcpu->kvm->arch.pmcr_n;
+	u8 n = vcpu->kvm->arch.nr_pmu_counters;
 
 	if (n)
 		mask |= GENMASK(n - 1, 0);
@@ -1217,7 +1217,7 @@ static int set_pmcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
 	 */
 	if (!kvm_vm_has_ran_once(kvm) &&
 	    new_n <= kvm_arm_pmu_get_max_counters(kvm))
-		kvm->arch.pmcr_n = new_n;
+		kvm->arch.nr_pmu_counters = new_n;
 
 	mutex_unlock(&kvm->arch.config_lock);