From c62d7a23b9479b946f00d58046e0bdf7f233a2b9 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 14 Feb 2024 13:18:03 +0000 Subject: [PATCH] KVM: arm64: Add feature checking helpers In order to make it easier to check whether a particular feature is exposed to a guest, add a new set of helpers, with kvm_has_feat() being the most useful. Let's start making use of them in the PMU code (courtesy of Oliver). Follow-up changes will introduce additional use patterns. Reviewed-by: Suzuki K Poulose Co-developed--by: Oliver Upton Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20240214131827.2856277-3-maz@kernel.org Signed-off-by: Oliver Upton --- arch/arm64/include/asm/kvm_host.h | 44 +++++++++++++++++++++++++++++++ arch/arm64/kvm/pmu-emul.c | 11 ++++---- arch/arm64/kvm/sys_regs.c | 6 ++--- include/kvm/arm_pmu.h | 11 -------- 4 files changed, 52 insertions(+), 20 deletions(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 21c57b812569..527da3d2cedb 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -1233,4 +1233,48 @@ static inline void kvm_hyp_reserve(void) { } void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu); bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu); +#define __expand_field_sign_unsigned(id, fld, val) \ + ((u64)SYS_FIELD_VALUE(id, fld, val)) + +#define __expand_field_sign_signed(id, fld, val) \ + ({ \ + u64 __val = SYS_FIELD_VALUE(id, fld, val); \ + sign_extend64(__val, id##_##fld##_WIDTH - 1); \ + }) + +#define expand_field_sign(id, fld, val) \ + (id##_##fld##_SIGNED ? \ + __expand_field_sign_signed(id, fld, val) : \ + __expand_field_sign_unsigned(id, fld, val)) + +#define get_idreg_field_unsigned(kvm, id, fld) \ + ({ \ + u64 __val = IDREG((kvm), SYS_##id); \ + FIELD_GET(id##_##fld##_MASK, __val); \ + }) + +#define get_idreg_field_signed(kvm, id, fld) \ + ({ \ + u64 __val = get_idreg_field_unsigned(kvm, id, fld); \ + sign_extend64(__val, id##_##fld##_WIDTH - 1); \ + }) + +#define get_idreg_field_enum(kvm, id, fld) \ + get_idreg_field_unsigned(kvm, id, fld) + +#define get_idreg_field(kvm, id, fld) \ + (id##_##fld##_SIGNED ? \ + get_idreg_field_signed(kvm, id, fld) : \ + get_idreg_field_unsigned(kvm, id, fld)) + +#define kvm_has_feat(kvm, id, fld, limit) \ + (get_idreg_field((kvm), id, fld) >= expand_field_sign(id, fld, limit)) + +#define kvm_has_feat_enum(kvm, id, fld, val) \ + (get_idreg_field_unsigned((kvm), id, fld) == __expand_field_sign_unsigned(id, fld, val)) + +#define kvm_has_feat_range(kvm, id, fld, min, max) \ + (get_idreg_field((kvm), id, fld) >= expand_field_sign(id, fld, min) && \ + get_idreg_field((kvm), id, fld) <= expand_field_sign(id, fld, max)) + #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index 3d9467ff73bc..925522470b2b 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -64,12 +64,11 @@ u64 kvm_pmu_evtyper_mask(struct kvm *kvm) { u64 mask = ARMV8_PMU_EXCLUDE_EL1 | ARMV8_PMU_EXCLUDE_EL0 | kvm_pmu_event_mask(kvm); - u64 pfr0 = IDREG(kvm, SYS_ID_AA64PFR0_EL1); - if (SYS_FIELD_GET(ID_AA64PFR0_EL1, EL2, pfr0)) + if (kvm_has_feat(kvm, ID_AA64PFR0_EL1, EL2, IMP)) mask |= ARMV8_PMU_INCLUDE_EL2; - if (SYS_FIELD_GET(ID_AA64PFR0_EL1, EL3, pfr0)) + if (kvm_has_feat(kvm, ID_AA64PFR0_EL1, EL3, IMP)) mask |= ARMV8_PMU_EXCLUDE_NS_EL0 | ARMV8_PMU_EXCLUDE_NS_EL1 | ARMV8_PMU_EXCLUDE_EL3; @@ -83,8 +82,10 @@ u64 kvm_pmu_evtyper_mask(struct kvm *kvm) */ static bool kvm_pmc_is_64bit(struct kvm_pmc *pmc) { + struct kvm_vcpu *vcpu = kvm_pmc_to_vcpu(pmc); + return (pmc->idx == ARMV8_PMU_CYCLE_IDX || - kvm_pmu_is_3p5(kvm_pmc_to_vcpu(pmc))); + kvm_has_feat(vcpu->kvm, ID_AA64DFR0_EL1, PMUVer, V3P5)); } static bool kvm_pmc_has_64bit_overflow(struct kvm_pmc *pmc) @@ -556,7 +557,7 @@ void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val) return; /* Fixup PMCR_EL0 to reconcile the PMU version and the LP bit */ - if (!kvm_pmu_is_3p5(vcpu)) + if (!kvm_has_feat(vcpu->kvm, ID_AA64DFR0_EL1, PMUVer, V3P5)) val &= ~ARMV8_PMU_PMCR_LP; /* The reset bits don't indicate any state, and shouldn't be saved. */ diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 041b11825578..3c31f8cb9eef 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -505,10 +505,9 @@ static bool trap_loregion(struct kvm_vcpu *vcpu, struct sys_reg_params *p, const struct sys_reg_desc *r) { - u64 val = IDREG(vcpu->kvm, SYS_ID_AA64MMFR1_EL1); u32 sr = reg_to_encoding(r); - if (!(val & (0xfUL << ID_AA64MMFR1_EL1_LO_SHIFT))) { + if (!kvm_has_feat(vcpu->kvm, ID_AA64MMFR1_EL1, LO, IMP)) { kvm_inject_undefined(vcpu); return false; } @@ -2748,8 +2747,7 @@ static bool trap_dbgdidr(struct kvm_vcpu *vcpu, return ignore_write(vcpu, p); } else { u64 dfr = IDREG(vcpu->kvm, SYS_ID_AA64DFR0_EL1); - u64 pfr = IDREG(vcpu->kvm, SYS_ID_AA64PFR0_EL1); - u32 el3 = !!SYS_FIELD_GET(ID_AA64PFR0_EL1, EL3, pfr); + u32 el3 = kvm_has_feat(vcpu->kvm, ID_AA64PFR0_EL1, EL3, IMP); p->regval = ((SYS_FIELD_GET(ID_AA64DFR0_EL1, WRPs, dfr) << 28) | (SYS_FIELD_GET(ID_AA64DFR0_EL1, BRPs, dfr) << 24) | diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h index 4b9d8fb393a8..eb4c369a79eb 100644 --- a/include/kvm/arm_pmu.h +++ b/include/kvm/arm_pmu.h @@ -90,16 +90,6 @@ void kvm_vcpu_pmu_resync_el0(void); vcpu->arch.pmu.events = *kvm_get_pmu_events(); \ } while (0) -/* - * Evaluates as true when emulating PMUv3p5, and false otherwise. - */ -#define kvm_pmu_is_3p5(vcpu) ({ \ - u64 val = IDREG(vcpu->kvm, SYS_ID_AA64DFR0_EL1); \ - u8 pmuver = SYS_FIELD_GET(ID_AA64DFR0_EL1, PMUVer, val); \ - \ - pmuver >= ID_AA64DFR0_EL1_PMUVer_V3P5; \ -}) - u8 kvm_arm_pmu_get_pmuver_limit(void); u64 kvm_pmu_evtyper_mask(struct kvm *kvm); int kvm_arm_set_default_pmu(struct kvm *kvm); @@ -168,7 +158,6 @@ static inline u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1) } #define kvm_vcpu_has_pmu(vcpu) ({ false; }) -#define kvm_pmu_is_3p5(vcpu) ({ false; }) static inline void kvm_pmu_update_vcpu_events(struct kvm_vcpu *vcpu) {} static inline void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu) {} static inline void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu) {}