KVM: x86/pmu: Change ambiguous _mask suffix to _rsvd in kvm_pmu

Several '_mask' suffixed variables such as, global_ctrl_mask, are
defined in kvm_pmu structure. However the _mask suffix is ambiguous and
misleading since it's not a real mask with positive logic. On the contrary
it represents the reserved bits of corresponding MSRs and these bits
should not be accessed.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20240430005239.13527-2-dapeng1.mi@linux.intel.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Author: Dapeng Mi

arch/x86/include/asm/kvm_host.h

@@ -546,12 +546,12 @@ struct kvm_pmu {
 	unsigned nr_arch_fixed_counters;
 	unsigned available_event_types;
 	u64 fixed_ctr_ctrl;
-	u64 fixed_ctr_ctrl_mask;
+	u64 fixed_ctr_ctrl_rsvd;
 	u64 global_ctrl;
 	u64 global_status;
 	u64 counter_bitmask[2];
-	u64 global_ctrl_mask;
-	u64 global_status_mask;
+	u64 global_ctrl_rsvd;
+	u64 global_status_rsvd;
 	u64 reserved_bits;
 	u64 raw_event_mask;
 	struct kvm_pmc gp_counters[KVM_INTEL_PMC_MAX_GENERIC];
@@ -571,9 +571,9 @@ struct kvm_pmu {
 
 	u64 ds_area;
 	u64 pebs_enable;
-	u64 pebs_enable_mask;
+	u64 pebs_enable_rsvd;
 	u64 pebs_data_cfg;
-	u64 pebs_data_cfg_mask;
+	u64 pebs_data_cfg_rsvd;
 
 	/*
 	 * If a guest counter is cross-mapped to host counter with different

arch/x86/kvm/pmu.c

@@ -681,13 +681,13 @@ int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 		if (!msr_info->host_initiated)
 			break;
 
-		if (data & pmu->global_status_mask)
+		if (data & pmu->global_status_rsvd)
 			return 1;
 
 		pmu->global_status = data;
 		break;
 	case MSR_AMD64_PERF_CNTR_GLOBAL_CTL:
-		data &= ~pmu->global_ctrl_mask;
+		data &= ~pmu->global_ctrl_rsvd;
 		fallthrough;
 	case MSR_CORE_PERF_GLOBAL_CTRL:
 		if (!kvm_valid_perf_global_ctrl(pmu, data))
@@ -704,7 +704,7 @@ int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 		 * GLOBAL_OVF_CTRL, a.k.a. GLOBAL STATUS_RESET, clears bits in
 		 * GLOBAL_STATUS, and so the set of reserved bits is the same.
 		 */
-		if (data & pmu->global_status_mask)
+		if (data & pmu->global_status_rsvd)
 			return 1;
 		fallthrough;
 	case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR:
@@ -768,11 +768,11 @@ void kvm_pmu_refresh(struct kvm_vcpu *vcpu)
 	pmu->counter_bitmask[KVM_PMC_FIXED] = 0;
 	pmu->reserved_bits = 0xffffffff00200000ull;
 	pmu->raw_event_mask = X86_RAW_EVENT_MASK;
-	pmu->global_ctrl_mask = ~0ull;
-	pmu->global_status_mask = ~0ull;
-	pmu->fixed_ctr_ctrl_mask = ~0ull;
-	pmu->pebs_enable_mask = ~0ull;
-	pmu->pebs_data_cfg_mask = ~0ull;
+	pmu->global_ctrl_rsvd = ~0ull;
+	pmu->global_status_rsvd = ~0ull;
+	pmu->fixed_ctr_ctrl_rsvd = ~0ull;
+	pmu->pebs_enable_rsvd = ~0ull;
+	pmu->pebs_data_cfg_rsvd = ~0ull;
 	bitmap_zero(pmu->all_valid_pmc_idx, X86_PMC_IDX_MAX);
 
 	if (!vcpu->kvm->arch.enable_pmu)

arch/x86/kvm/pmu.h

@@ -129,7 +129,7 @@ static inline bool pmc_is_fixed(struct kvm_pmc *pmc)
 static inline bool kvm_valid_perf_global_ctrl(struct kvm_pmu *pmu,
 						 u64 data)
 {
-	return !(pmu->global_ctrl_mask & data);
+	return !(pmu->global_ctrl_rsvd & data);
 }
 
 /* returns general purpose PMC with the specified MSR. Note that it can be

arch/x86/kvm/svm/pmu.c

@@ -199,8 +199,8 @@ static void amd_pmu_refresh(struct kvm_vcpu *vcpu)
 					 kvm_pmu_cap.num_counters_gp);
 
 	if (pmu->version > 1) {
-		pmu->global_ctrl_mask = ~((1ull << pmu->nr_arch_gp_counters) - 1);
-		pmu->global_status_mask = pmu->global_ctrl_mask;
+		pmu->global_ctrl_rsvd = ~((1ull << pmu->nr_arch_gp_counters) - 1);
+		pmu->global_status_rsvd = pmu->global_ctrl_rsvd;
 	}
 
 	pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << 48) - 1;

arch/x86/kvm/vmx/pmu_intel.c

@@ -348,14 +348,14 @@ static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 
 	switch (msr) {
 	case MSR_CORE_PERF_FIXED_CTR_CTRL:
-		if (data & pmu->fixed_ctr_ctrl_mask)
+		if (data & pmu->fixed_ctr_ctrl_rsvd)
 			return 1;
 
 		if (pmu->fixed_ctr_ctrl != data)
 			reprogram_fixed_counters(pmu, data);
 		break;
 	case MSR_IA32_PEBS_ENABLE:
-		if (data & pmu->pebs_enable_mask)
+		if (data & pmu->pebs_enable_rsvd)
 			return 1;
 
 		if (pmu->pebs_enable != data) {
@@ -371,7 +371,7 @@ static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 		pmu->ds_area = data;
 		break;
 	case MSR_PEBS_DATA_CFG:
-		if (data & pmu->pebs_data_cfg_mask)
+		if (data & pmu->pebs_data_cfg_rsvd)
 			return 1;
 
 		pmu->pebs_data_cfg = data;
@@ -456,7 +456,7 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
 	union cpuid10_eax eax;
 	union cpuid10_edx edx;
 	u64 perf_capabilities;
-	u64 counter_mask;
+	u64 counter_rsvd;
 	int i;
 
 	memset(&lbr_desc->records, 0, sizeof(lbr_desc->records));
@@ -502,21 +502,21 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
 	}
 
 	for (i = 0; i < pmu->nr_arch_fixed_counters; i++)
-		pmu->fixed_ctr_ctrl_mask &= ~(0xbull << (i * 4));
-	counter_mask = ~(((1ull << pmu->nr_arch_gp_counters) - 1) |
+		pmu->fixed_ctr_ctrl_rsvd &= ~(0xbull << (i * 4));
+	counter_rsvd = ~(((1ull << pmu->nr_arch_gp_counters) - 1) |
 		(((1ull << pmu->nr_arch_fixed_counters) - 1) << KVM_FIXED_PMC_BASE_IDX));
-	pmu->global_ctrl_mask = counter_mask;
+	pmu->global_ctrl_rsvd = counter_rsvd;
 
 	/*
 	 * GLOBAL_STATUS and GLOBAL_OVF_CONTROL (a.k.a. GLOBAL_STATUS_RESET)
 	 * share reserved bit definitions.  The kernel just happens to use
 	 * OVF_CTRL for the names.
 	 */
-	pmu->global_status_mask = pmu->global_ctrl_mask
+	pmu->global_status_rsvd = pmu->global_ctrl_rsvd
 			& ~(MSR_CORE_PERF_GLOBAL_OVF_CTRL_OVF_BUF |
 			    MSR_CORE_PERF_GLOBAL_OVF_CTRL_COND_CHGD);
 	if (vmx_pt_mode_is_host_guest())
-		pmu->global_status_mask &=
+		pmu->global_status_rsvd &=
 				~MSR_CORE_PERF_GLOBAL_OVF_CTRL_TRACE_TOPA_PMI;
 
 	entry = kvm_find_cpuid_entry_index(vcpu, 7, 0);
@@ -544,15 +544,15 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
 
 	if (perf_capabilities & PERF_CAP_PEBS_FORMAT) {
 		if (perf_capabilities & PERF_CAP_PEBS_BASELINE) {
-			pmu->pebs_enable_mask = counter_mask;
+			pmu->pebs_enable_rsvd = counter_rsvd;
 			pmu->reserved_bits &= ~ICL_EVENTSEL_ADAPTIVE;
 			for (i = 0; i < pmu->nr_arch_fixed_counters; i++) {
-				pmu->fixed_ctr_ctrl_mask &=
+				pmu->fixed_ctr_ctrl_rsvd &=
 					~(1ULL << (KVM_FIXED_PMC_BASE_IDX + i * 4));
 			}
-			pmu->pebs_data_cfg_mask = ~0xff00000full;
+			pmu->pebs_data_cfg_rsvd = ~0xff00000full;
 		} else {
-			pmu->pebs_enable_mask =
+			pmu->pebs_enable_rsvd =
 				~((1ull << pmu->nr_arch_gp_counters) - 1);
 		}
 	}