s390x/kvm: implement CPU model support (3b84c25c) · Commits · SUMMER2020 / students / proj-2021291

target-s390x/cpu_models.c

+72 −3

Original line number	Diff line number	Diff line
		@@ -162,6 +162,61 @@ bool s390_has_feat(S390Feat feat)
		return test_bit(feat, cpu->model->features);
		}

		uint8_t s390_get_gen_for_cpu_type(uint16_t type)
		{
		int i;

		for (i = 0; i < ARRAY_SIZE(s390_cpu_defs); i++) {
		if (s390_cpu_defs[i].type == type) {
		return s390_cpu_defs[i].gen;
		}
		}
		return 0;
		}

		const S390CPUDef *s390_find_cpu_def(uint16_t type, uint8_t gen, uint8_t ec_ga,
		S390FeatBitmap features)
		{
		const S390CPUDef *last_compatible = NULL;
		int i;

		if (!gen) {
		ec_ga = 0;
		}
		if (!gen && type) {
		gen = s390_get_gen_for_cpu_type(type);
		}

		for (i = 0; i < ARRAY_SIZE(s390_cpu_defs); i++) {
		const S390CPUDef *def = &s390_cpu_defs[i];
		S390FeatBitmap missing;

		/* don't even try newer generations if we know the generation */
		if (gen) {
		if (def->gen > gen) {
		break;
		} else if (def->gen == gen && ec_ga && def->ec_ga > ec_ga) {
		break;
		}
		}

		if (features) {
		/* see if the model satisfies the minimum features */
		bitmap_andnot(missing, def->base_feat, features, S390_FEAT_MAX);
		if (!bitmap_empty(missing, S390_FEAT_MAX)) {
		break;
		}
		}

		/* stop the search if we found the exact model */
		if (def->type == type && def->ec_ga == ec_ga) {
		return def;
		}
		last_compatible = def;
		}
		return last_compatible;
		}

		struct S390PrintCpuListInfo {
		FILE *f;
		fprintf_function print;
		@@ -324,7 +379,7 @@ static S390CPUModel get_max_cpu_model(Error *errp)
		}

		if (kvm_enabled()) {
		error_setg(errp, "KVM does not support CPU models.");
		kvm_s390_get_host_cpu_model(&max_model, errp);
		} else {
		/* TCG enulates a z900 */
		max_model.def = &s390_cpu_defs[0];
		@@ -357,8 +412,7 @@ static inline void apply_cpu_model(const S390CPUModel model, Error *errp)
		}

		if (kvm_enabled()) {
		/* FIXME KVM */
		error_setg(errp, "KVM doesn't support CPU models.");
		kvm_s390_apply_cpu_model(model, errp);
		} else if (model) {
		/* FIXME TCG - use data for stdip/stfl */
		}
		@@ -563,6 +617,21 @@ static void s390_cpu_model_initfn(Object *obj)
		#ifdef CONFIG_KVM
		static void s390_host_cpu_model_initfn(Object *obj)
		{
		S390CPU *cpu = S390_CPU(obj);
		Error *err = NULL;

		if (!kvm_enabled() \|\| !kvm_s390_cpu_models_supported()) {
		return;
		}

		cpu->model = g_malloc0(sizeof(*cpu->model));
		kvm_s390_get_host_cpu_model(cpu->model, &err);
		if (err) {
		error_report_err(err);
		g_free(cpu->model);
		/* fallback to unsupported cpu models */
		cpu->model = NULL;
		}
		}
		#endif

target-s390x/cpu_models.h

+50 −0

Original line number	Diff line number	Diff line
		@@ -49,7 +49,25 @@ typedef struct S390CPUModel {
		uint8_t cpu_ver; /* CPU version, usually "ff" for kvm */
		} S390CPUModel;

		/*
		* CPU ID
		*
		* bits 0-7: Zeroes (ff for kvm)
		* bits 8-31: CPU ID (serial number)
		* bits 32-48: Machine type
		* bits 48-63: Zeroes
		*/
		#define cpuid_type(x) (((x) >> 16) & 0xffff)
		#define cpuid_id(x) (((x) >> 32) & 0xffffff)
		#define cpuid_ver(x) (((x) >> 56) & 0xff)

		#define lowest_ibc(x) (((uint32_t)(x) >> 16) & 0xfff)
		#define unblocked_ibc(x) ((uint32_t)(x) & 0xfff)
		#define has_ibc(x) (lowest_ibc(x) != 0)

		#define S390_GEN_Z10 0xa
		#define ibc_gen(x) (x == 0 ? 0 : ((x >> 4) + S390_GEN_Z10))
		#define ibc_ec_ga(x) (x & 0xf)

		uint32_t s390_get_hmfai(void);
		uint8_t s390_get_mha_pow(void);
		@@ -65,5 +83,37 @@ static inline uint16_t s390_ibc_from_cpu_model(const S390CPUModel *model)
		}
		void s390_get_feat_block(S390FeatType type, uint8_t *data);
		bool s390_has_feat(S390Feat feat);
		uint8_t s390_get_gen_for_cpu_type(uint16_t type);
		static inline bool s390_known_cpu_type(uint16_t type)
		{
		return s390_get_gen_for_cpu_type(type) != 0;
		}
		static inline uint64_t s390_cpuid_from_cpu_model(const S390CPUModel *model)
		{
		return ((uint64_t)model->cpu_ver << 56) \|
		((uint64_t)model->cpu_id << 32) \|
		((uint64_t)model->def->type << 16);
		}
		S390CPUDef const *s390_find_cpu_def(uint16_t type, uint8_t gen, uint8_t ec_ga,
		S390FeatBitmap features);

		#ifdef CONFIG_KVM
		bool kvm_s390_cpu_models_supported(void);
		void kvm_s390_get_host_cpu_model(S390CPUModel model, Error *errp);
		void kvm_s390_apply_cpu_model(const S390CPUModel model, Error *errp);
		#else
		static inline void kvm_s390_get_host_cpu_model(S390CPUModel *model,
		Error **errp)
		{
		}
		static inline void kvm_s390_apply_cpu_model(const S390CPUModel *model,
		Error **errp)
		{
		}
		static inline bool kvm_s390_cpu_models_supported(void)
		{
		return false;
		}
		#endif

		#endif /* TARGET_S390X_CPU_MODELS_H */

target-s390x/kvm.c

+295 −0

Original line number	Diff line number	Diff line
		@@ -2312,3 +2312,298 @@ int kvm_arch_msi_data_to_gsi(uint32_t data)
		{
		abort();
		}

		static inline int test_bit_inv(long nr, const unsigned long *addr)
		{
		return test_bit(BE_BIT_NR(nr), addr);
		}

		static inline void set_bit_inv(long nr, unsigned long *addr)
		{
		set_bit(BE_BIT_NR(nr), addr);
		}

		static int query_cpu_subfunc(S390FeatBitmap features)
		{
		struct kvm_s390_vm_cpu_subfunc prop;
		struct kvm_device_attr attr = {
		.group = KVM_S390_VM_CPU_MODEL,
		.attr = KVM_S390_VM_CPU_MACHINE_SUBFUNC,
		.addr = (uint64_t) &prop,
		};
		int rc;

		rc = kvm_vm_ioctl(kvm_state, KVM_GET_DEVICE_ATTR, &attr);
		if (rc) {
		return rc;
		}

		/*
		* We're going to add all subfunctions now, if the corresponding feature
		* is available that unlocks the query functions.
		*/
		s390_add_from_feat_block(features, S390_FEAT_TYPE_PLO, prop.plo);
		if (test_bit(S390_FEAT_TOD_CLOCK_STEERING, features)) {
		s390_add_from_feat_block(features, S390_FEAT_TYPE_PTFF, prop.ptff);
		}
		if (test_bit(S390_FEAT_MSA, features)) {
		s390_add_from_feat_block(features, S390_FEAT_TYPE_KMAC, prop.kmac);
		s390_add_from_feat_block(features, S390_FEAT_TYPE_KMC, prop.kmc);
		s390_add_from_feat_block(features, S390_FEAT_TYPE_KM, prop.km);
		s390_add_from_feat_block(features, S390_FEAT_TYPE_KIMD, prop.kimd);
		s390_add_from_feat_block(features, S390_FEAT_TYPE_KLMD, prop.klmd);
		}
		if (test_bit(S390_FEAT_MSA_EXT_3, features)) {
		s390_add_from_feat_block(features, S390_FEAT_TYPE_PCKMO, prop.pckmo);
		}
		if (test_bit(S390_FEAT_MSA_EXT_4, features)) {
		s390_add_from_feat_block(features, S390_FEAT_TYPE_KMCTR, prop.kmctr);
		s390_add_from_feat_block(features, S390_FEAT_TYPE_KMF, prop.kmf);
		s390_add_from_feat_block(features, S390_FEAT_TYPE_KMO, prop.kmo);
		s390_add_from_feat_block(features, S390_FEAT_TYPE_PCC, prop.pcc);
		}
		if (test_bit(S390_FEAT_MSA_EXT_5, features)) {
		s390_add_from_feat_block(features, S390_FEAT_TYPE_PPNO, prop.ppno);
		}
		return 0;
		}

		static int configure_cpu_subfunc(const S390FeatBitmap features)
		{
		struct kvm_s390_vm_cpu_subfunc prop = {};
		struct kvm_device_attr attr = {
		.group = KVM_S390_VM_CPU_MODEL,
		.attr = KVM_S390_VM_CPU_PROCESSOR_SUBFUNC,
		.addr = (uint64_t) &prop,
		};

		if (!kvm_vm_check_attr(kvm_state, KVM_S390_VM_CPU_MODEL,
		KVM_S390_VM_CPU_PROCESSOR_SUBFUNC)) {
		/* hardware support might be missing, IBC will handle most of this */
		return 0;
		}

		s390_fill_feat_block(features, S390_FEAT_TYPE_PLO, prop.plo);
		if (test_bit(S390_FEAT_TOD_CLOCK_STEERING, features)) {
		s390_fill_feat_block(features, S390_FEAT_TYPE_PTFF, prop.ptff);
		prop.ptff[0] \|= 0x80; /* query is always available */
		}
		if (test_bit(S390_FEAT_MSA, features)) {
		s390_fill_feat_block(features, S390_FEAT_TYPE_KMAC, prop.kmac);
		prop.kmac[0] \|= 0x80; /* query is always available */
		s390_fill_feat_block(features, S390_FEAT_TYPE_KMC, prop.kmc);
		prop.kmc[0] \|= 0x80; /* query is always available */
		s390_fill_feat_block(features, S390_FEAT_TYPE_KM, prop.km);
		prop.km[0] \|= 0x80; /* query is always available */
		s390_fill_feat_block(features, S390_FEAT_TYPE_KIMD, prop.kimd);
		prop.kimd[0] \|= 0x80; /* query is always available */
		s390_fill_feat_block(features, S390_FEAT_TYPE_KLMD, prop.klmd);
		prop.klmd[0] \|= 0x80; /* query is always available */
		}
		if (test_bit(S390_FEAT_MSA_EXT_3, features)) {
		s390_fill_feat_block(features, S390_FEAT_TYPE_PCKMO, prop.pckmo);
		prop.pckmo[0] \|= 0x80; /* query is always available */
		}
		if (test_bit(S390_FEAT_MSA_EXT_4, features)) {
		s390_fill_feat_block(features, S390_FEAT_TYPE_KMCTR, prop.kmctr);
		prop.kmctr[0] \|= 0x80; /* query is always available */
		s390_fill_feat_block(features, S390_FEAT_TYPE_KMF, prop.kmf);
		prop.kmf[0] \|= 0x80; /* query is always available */
		s390_fill_feat_block(features, S390_FEAT_TYPE_KMO, prop.kmo);
		prop.kmo[0] \|= 0x80; /* query is always available */
		s390_fill_feat_block(features, S390_FEAT_TYPE_PCC, prop.pcc);
		prop.pcc[0] \|= 0x80; /* query is always available */
		}
		if (test_bit(S390_FEAT_MSA_EXT_5, features)) {
		s390_fill_feat_block(features, S390_FEAT_TYPE_PPNO, prop.ppno);
		prop.ppno[0] \|= 0x80; /* query is always available */
		}
		return kvm_vm_ioctl(kvm_state, KVM_SET_DEVICE_ATTR, &attr);
		}

		static int kvm_to_feat[][2] = {
		{ KVM_S390_VM_CPU_FEAT_ESOP, S390_FEAT_ESOP },
		{ KVM_S390_VM_CPU_FEAT_SIEF2, S390_FEAT_SIE_F2 },
		{ KVM_S390_VM_CPU_FEAT_64BSCAO , S390_FEAT_SIE_64BSCAO },
		{ KVM_S390_VM_CPU_FEAT_SIIF, S390_FEAT_SIE_SIIF },
		{ KVM_S390_VM_CPU_FEAT_GPERE, S390_FEAT_SIE_GPERE },
		{ KVM_S390_VM_CPU_FEAT_GSLS, S390_FEAT_SIE_GSLS },
		{ KVM_S390_VM_CPU_FEAT_IB, S390_FEAT_SIE_IB },
		{ KVM_S390_VM_CPU_FEAT_CEI, S390_FEAT_SIE_CEI },
		{ KVM_S390_VM_CPU_FEAT_IBS, S390_FEAT_SIE_IBS },
		{ KVM_S390_VM_CPU_FEAT_SKEY, S390_FEAT_SIE_SKEY },
		{ KVM_S390_VM_CPU_FEAT_CMMA, S390_FEAT_SIE_CMMA },
		{ KVM_S390_VM_CPU_FEAT_PFMFI, S390_FEAT_SIE_PFMFI},
		{ KVM_S390_VM_CPU_FEAT_SIGPIF, S390_FEAT_SIE_SIGPIF},
		};

		static int query_cpu_feat(S390FeatBitmap features)
		{
		struct kvm_s390_vm_cpu_feat prop;
		struct kvm_device_attr attr = {
		.group = KVM_S390_VM_CPU_MODEL,
		.attr = KVM_S390_VM_CPU_MACHINE_FEAT,
		.addr = (uint64_t) &prop,
		};
		int rc;
		int i;

		rc = kvm_vm_ioctl(kvm_state, KVM_GET_DEVICE_ATTR, &attr);
		if (rc) {
		return rc;
		}

		for (i = 0; i < ARRAY_SIZE(kvm_to_feat); i++) {
		if (test_bit_inv(kvm_to_feat[i][0], (unsigned long *)prop.feat)) {
		set_bit(kvm_to_feat[i][1], features);
		}
		}
		return 0;
		}

		static int configure_cpu_feat(const S390FeatBitmap features)
		{
		struct kvm_s390_vm_cpu_feat prop = {};
		struct kvm_device_attr attr = {
		.group = KVM_S390_VM_CPU_MODEL,
		.attr = KVM_S390_VM_CPU_PROCESSOR_FEAT,
		.addr = (uint64_t) &prop,
		};
		int i;

		for (i = 0; i < ARRAY_SIZE(kvm_to_feat); i++) {
		if (test_bit(kvm_to_feat[i][1], features)) {
		set_bit_inv(kvm_to_feat[i][0], (unsigned long *)prop.feat);
		}
		}
		return kvm_vm_ioctl(kvm_state, KVM_SET_DEVICE_ATTR, &attr);
		}

		bool kvm_s390_cpu_models_supported(void)
		{
		return kvm_vm_check_attr(kvm_state, KVM_S390_VM_CPU_MODEL,
		KVM_S390_VM_CPU_MACHINE) &&
		kvm_vm_check_attr(kvm_state, KVM_S390_VM_CPU_MODEL,
		KVM_S390_VM_CPU_PROCESSOR) &&
		kvm_vm_check_attr(kvm_state, KVM_S390_VM_CPU_MODEL,
		KVM_S390_VM_CPU_MACHINE_FEAT) &&
		kvm_vm_check_attr(kvm_state, KVM_S390_VM_CPU_MODEL,
		KVM_S390_VM_CPU_PROCESSOR_FEAT) &&
		kvm_vm_check_attr(kvm_state, KVM_S390_VM_CPU_MODEL,
		KVM_S390_VM_CPU_MACHINE_SUBFUNC);
		}

		void kvm_s390_get_host_cpu_model(S390CPUModel model, Error *errp)
		{
		struct kvm_s390_vm_cpu_machine prop = {};
		struct kvm_device_attr attr = {
		.group = KVM_S390_VM_CPU_MODEL,
		.attr = KVM_S390_VM_CPU_MACHINE,
		.addr = (uint64_t) &prop,
		};
		uint16_t unblocked_ibc = 0, cpu_type = 0;
		int rc;

		memset(model, 0, sizeof(*model));

		if (!kvm_s390_cpu_models_supported()) {
		error_setg(errp, "KVM doesn't support CPU models");
		return;
		}

		/* query the basic cpu model properties */
		rc = kvm_vm_ioctl(kvm_state, KVM_GET_DEVICE_ATTR, &attr);
		if (rc) {
		error_setg(errp, "KVM: Error querying host CPU model: %d", rc);
		return;
		}

		cpu_type = cpuid_type(prop.cpuid);
		if (has_ibc(prop.ibc)) {
		model->lowest_ibc = lowest_ibc(prop.ibc);
		unblocked_ibc = unblocked_ibc(prop.ibc);
		}
		model->cpu_id = cpuid_id(prop.cpuid);
		model->cpu_ver = 0xff;

		/* get supported cpu features indicated via STFL(E) */
		s390_add_from_feat_block(model->features, S390_FEAT_TYPE_STFL,
		(uint8_t *) prop.fac_mask);
		/* dat-enhancement facility 2 has no bit but was introduced with stfle */
		if (test_bit(S390_FEAT_STFLE, model->features)) {
		set_bit(S390_FEAT_DAT_ENH_2, model->features);
		}
		/* get supported cpu features indicated e.g. via SCLP */
		rc = query_cpu_feat(model->features);
		if (rc) {
		error_setg(errp, "KVM: Error querying CPU features: %d", rc);
		return;
		}
		/* get supported cpu subfunctions indicated via query / test bit */
		rc = query_cpu_subfunc(model->features);
		if (rc) {
		error_setg(errp, "KVM: Error querying CPU subfunctions: %d", rc);
		return;
		}

		if (s390_known_cpu_type(cpu_type)) {
		/* we want the exact model, even if some features are missing */
		model->def = s390_find_cpu_def(cpu_type, ibc_gen(unblocked_ibc),
		ibc_ec_ga(unblocked_ibc), NULL);
		} else {
		/* model unknown, e.g. too new - search using features */
		model->def = s390_find_cpu_def(0, ibc_gen(unblocked_ibc),
		ibc_ec_ga(unblocked_ibc),
		model->features);
		}
		if (!model->def) {
		error_setg(errp, "KVM: host CPU model could not be identified");
		return;
		}
		/* strip of features that are not part of the maximum model */
		bitmap_and(model->features, model->features, model->def->full_feat,
		S390_FEAT_MAX);
		}

		void kvm_s390_apply_cpu_model(const S390CPUModel model, Error *errp)
		{
		struct kvm_s390_vm_cpu_processor prop = {
		.fac_list = { 0 },
		};
		struct kvm_device_attr attr = {
		.group = KVM_S390_VM_CPU_MODEL,
		.attr = KVM_S390_VM_CPU_PROCESSOR,
		.addr = (uint64_t) &prop,
		};
		int rc;

		if (!model) {
		return;
		}
		if (!kvm_s390_cpu_models_supported()) {
		error_setg(errp, "KVM doesn't support CPU models");
		return;
		}
		prop.cpuid = s390_cpuid_from_cpu_model(model);
		prop.ibc = s390_ibc_from_cpu_model(model);
		/* configure cpu features indicated via STFL(e) */
		s390_fill_feat_block(model->features, S390_FEAT_TYPE_STFL,
		(uint8_t *) prop.fac_list);
		rc = kvm_vm_ioctl(kvm_state, KVM_SET_DEVICE_ATTR, &attr);
		if (rc) {
		error_setg(errp, "KVM: Error configuring the CPU model: %d", rc);
		return;
		}
		/* configure cpu features indicated e.g. via SCLP */
		rc = configure_cpu_feat(model->features);
		if (rc) {
		error_setg(errp, "KVM: Error configuring CPU features: %d", rc);
		return;
		}
		/* configure cpu subfunctions indicated via query / test bit */
		rc = configure_cpu_subfunc(model->features);
		if (rc) {
		error_setg(errp, "KVM: Error configuring CPU subfunctions: %d", rc);
		return;
		}
		}