diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index f1fb66bff1c0a64c779c24407391e99e53412cf3..b09ca3f2937996d3003ff16547e4e51dda8a2db4 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -6763,6 +6763,15 @@ guest according to the bits in the KVM_CPUID_FEATURES CPUID leaf (0x40000001). Otherwise, a guest may use the paravirtual features regardless of what has actually been exposed through the CPUID leaf. +8.31 KVM_CAP_PTP_KVM +-------------------- + +:Architectures: arm64 + +This capability indicates that the KVM virtual PTP service is +supported in the host. A VMM can check whether the service is +available to the guest on migration. + 9. Known KVM API problems ========================= diff --git a/Documentation/virt/kvm/arm/index.rst b/Documentation/virt/kvm/arm/index.rst index 3e2b2aba90fcc114c5cd96a2ea1f75fe5bb3021b..78a9b670aafee61ca9bdc974ec41dd777248ea59 100644 --- a/Documentation/virt/kvm/arm/index.rst +++ b/Documentation/virt/kvm/arm/index.rst @@ -10,3 +10,4 @@ ARM hyp-abi psci pvtime + ptp_kvm diff --git a/Documentation/virt/kvm/arm/ptp_kvm.rst b/Documentation/virt/kvm/arm/ptp_kvm.rst new file mode 100644 index 0000000000000000000000000000000000000000..5fbed2e51c1a7756b3824835342e7212536fc173 --- /dev/null +++ b/Documentation/virt/kvm/arm/ptp_kvm.rst @@ -0,0 +1,25 @@ +.. SPDX-License-Identifier: GPL-2.0 + +PTP_KVM support for arm/arm64 +============================= + +PTP_KVM is used for high precision time sync between host and guests. +It relies on transferring the wall clock and counter value from the +host to the guest using a KVM-specific hypercall. + +* ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID: 0x86000001 + +This hypercall uses the SMC32/HVC32 calling convention: + +ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID + ============= ========== ========== + Function ID: (uint32) 0x86000001 + Arguments: (uint32) KVM_PTP_VIRT_COUNTER(0) + KVM_PTP_PHYS_COUNTER(1) + Return Values: (int32) NOT_SUPPORTED(-1) on error, or + (uint32) Upper 32 bits of wall clock time (r0) + (uint32) Lower 32 bits of wall clock time (r1) + (uint32) Upper 32 bits of counter (r2) + (uint32) Lower 32 bits of counter (r3) + Endianness: No Restrictions. + ============= ========== ========== diff --git a/arch/arm/include/asm/hypervisor.h b/arch/arm/include/asm/hypervisor.h index df8524365637acf6e138ae223241157370b72385..bd61502b97153cfb83b12ccb9e2d5c42e8df6572 100644 --- a/arch/arm/include/asm/hypervisor.h +++ b/arch/arm/include/asm/hypervisor.h @@ -4,4 +4,7 @@ #include +void kvm_init_hyp_services(void); +bool kvm_arm_hyp_service_available(u32 func_id); + #endif diff --git a/arch/arm64/configs/openeuler_defconfig b/arch/arm64/configs/openeuler_defconfig index ea00de680354191292de9378943b0580ad1824af..831a857f6268cb7532f1ef9e45b5f2826fdb4b94 100644 --- a/arch/arm64/configs/openeuler_defconfig +++ b/arch/arm64/configs/openeuler_defconfig @@ -3647,6 +3647,7 @@ CONFIG_PPS_CLIENT_GPIO=m CONFIG_PTP_1588_CLOCK=y CONFIG_DP83640_PHY=m # CONFIG_PTP_1588_CLOCK_INES is not set +CONFIG_PTP_1588_CLOCK_KVM=m # CONFIG_PTP_1588_CLOCK_IDT82P33 is not set # CONFIG_PTP_1588_CLOCK_IDTCM is not set CONFIG_PTP_HISI=m diff --git a/arch/arm64/include/asm/hypervisor.h b/arch/arm64/include/asm/hypervisor.h index f9cc1d021791504ee87b18ee22bb8896f4193a99..0ae427f352c8cab9440ae723735c396794cbe208 100644 --- a/arch/arm64/include/asm/hypervisor.h +++ b/arch/arm64/include/asm/hypervisor.h @@ -4,4 +4,7 @@ #include +void kvm_init_hyp_services(void); +bool kvm_arm_hyp_service_available(u32 func_id); + #endif diff --git a/arch/arm64/include/asm/kvm_para.h b/arch/arm64/include/asm/kvm_para.h index e1ecc089ee9b8414f0dfe12658238773e62cb819..1e3786fe244ffe2fe01787e2c251b95d7d41aed3 100644 --- a/arch/arm64/include/asm/kvm_para.h +++ b/arch/arm64/include/asm/kvm_para.h @@ -2,7 +2,7 @@ #ifndef _ASM_ARM64_KVM_PARA_H #define _ASM_ARM64_KVM_PARA_H -#define KVM_HINTS_REALTIME 0 +#include static inline bool kvm_check_and_clear_guest_paused(void) { diff --git a/arch/arm64/include/uapi/asm/Kbuild b/arch/arm64/include/uapi/asm/Kbuild index 602d137932dcef659fc39c6eef6160bc2182f25b..28b7a35ebcc551b052903ceeca7d895007364dd2 100644 --- a/arch/arm64/include/uapi/asm/Kbuild +++ b/arch/arm64/include/uapi/asm/Kbuild @@ -1,3 +1,3 @@ # SPDX-License-Identifier: GPL-2.0 -generic-y += kvm_para.h +#generic-y += kvm_para.h diff --git a/arch/arm64/include/uapi/asm/kvm_para.h b/arch/arm64/include/uapi/asm/kvm_para.h new file mode 100644 index 0000000000000000000000000000000000000000..98832b7837ee0cf85e497cdfac1b9fb34bedbc96 --- /dev/null +++ b/arch/arm64/include/uapi/asm/kvm_para.h @@ -0,0 +1,7 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef _UAPI_ASM_ARM64_KVM_PARA_H +#define _UAPI_ASM_ARM64_KVM_PARA_H + +#define KVM_HINTS_REALTIME 0 + +#endif /* _UAPI_ASM_ARM64_KVM_PARA_H */ diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index bc5a91d17a713213080b14842abdfac901d19685..7dbfeae689dd7c96eeaee2214776adc872fbd6e0 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -228,6 +228,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_ARM_NISV_TO_USER: case KVM_CAP_ARM_INJECT_EXT_DABT: case KVM_CAP_ARM_CPU_FEATURE: + case KVM_CAP_PTP_KVM: r = 1; break; case KVM_CAP_ARM_SET_DEVICE_ADDR: diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c index 3ed08077fe15737a5fe1178e4fcf6cfb47fc2e56..ae22f72c0b474e07499793fa7330ac7200d338b3 100644 --- a/arch/arm64/kvm/hypercalls.c +++ b/arch/arm64/kvm/hypercalls.c @@ -9,16 +9,65 @@ #include #include +static void kvm_ptp_get_time(struct kvm_vcpu *vcpu, u64 *val) +{ + struct system_time_snapshot systime_snapshot; + u64 cycles = ~0UL; + u32 feature; + + /* + * system time and counter value must captured at the same + * time to keep consistency and precision. + */ + ktime_get_snapshot(&systime_snapshot); + + /* + * This is only valid if the current clocksource is the + * architected counter, as this is the only one the guest + * can see. + */ + if (systime_snapshot.cs_id != (short)CSID_ARM_ARCH_COUNTER) + return; + + /* + * The guest selects one of the two reference counters + * (virtual or physical) with the first argument of the SMCCC + * call. In case the identifier is not supported, error out. + */ + feature = smccc_get_arg1(vcpu); + switch (feature) { + case KVM_PTP_VIRT_COUNTER: + cycles = systime_snapshot.cycles - vcpu_read_sys_reg(vcpu, CNTVOFF_EL2); + break; + case KVM_PTP_PHYS_COUNTER: + cycles = systime_snapshot.cycles; + break; + default: + return; + } + + /* + * This relies on the top bit of val[0] never being set for + * valid values of system time, because that is *really* far + * in the future (about 292 years from 1970, and at that stage + * nobody will give a damn about it). + */ + val[0] = upper_32_bits(systime_snapshot.real); + val[1] = lower_32_bits(systime_snapshot.real); + val[2] = upper_32_bits(cycles); + val[3] = lower_32_bits(cycles); +} + int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) { u32 func_id = smccc_get_function(vcpu); - long val = SMCCC_RET_NOT_SUPPORTED; + u64 val[4] = {SMCCC_RET_NOT_SUPPORTED}; u32 feature; gpa_t gpa; switch (func_id) { case ARM_SMCCC_VERSION_FUNC_ID: - val = ARM_SMCCC_VERSION_1_1; + val[0] = ARM_SMCCC_VERSION_1_1; break; case ARM_SMCCC_ARCH_FEATURES_FUNC_ID: feature = smccc_get_arg1(vcpu); @@ -28,10 +77,10 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) case SPECTRE_VULNERABLE: break; case SPECTRE_MITIGATED: - val = SMCCC_RET_SUCCESS; + val[0] = SMCCC_RET_SUCCESS; break; case SPECTRE_UNAFFECTED: - val = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED; + val[0] = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED; break; } break; @@ -54,7 +103,7 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) break; fallthrough; case SPECTRE_UNAFFECTED: - val = SMCCC_RET_NOT_REQUIRED; + val[0] = SMCCC_RET_NOT_REQUIRED; break; } break; @@ -63,45 +112,58 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) case SPECTRE_VULNERABLE: break; case SPECTRE_MITIGATED: - val = SMCCC_RET_SUCCESS; + val[0] = SMCCC_RET_SUCCESS; break; case SPECTRE_UNAFFECTED: - val = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED; + val[0] = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED; break; } break; case ARM_SMCCC_HV_PV_TIME_FEATURES: - val = SMCCC_RET_SUCCESS; + val[0] = SMCCC_RET_SUCCESS; break; case ARM_SMCCC_HV_PV_SCHED_FEATURES: - val = SMCCC_RET_SUCCESS; + val[0] = SMCCC_RET_SUCCESS; break; } break; case ARM_SMCCC_HV_PV_TIME_FEATURES: - val = kvm_hypercall_pv_features(vcpu); + val[0] = kvm_hypercall_pv_features(vcpu); break; case ARM_SMCCC_HV_PV_TIME_ST: gpa = kvm_init_stolen_time(vcpu); if (gpa != GPA_INVALID) - val = gpa; + val[0] = gpa; + break; + case ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID: + val[0] = ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_0; + val[1] = ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_1; + val[2] = ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_2; + val[3] = ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_3; + break; + case ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID: + val[0] = BIT(ARM_SMCCC_KVM_FUNC_FEATURES); + val[0] |= BIT(ARM_SMCCC_KVM_FUNC_PTP); + break; + case ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID: + kvm_ptp_get_time(vcpu, val); break; case ARM_SMCCC_HV_PV_SCHED_FEATURES: - val = kvm_hypercall_pvsched_features(vcpu); + val[0] = kvm_hypercall_pvsched_features(vcpu); break; case ARM_SMCCC_HV_PV_SCHED_IPA_INIT: gpa = smccc_get_arg1(vcpu); if (gpa != GPA_INVALID) { vcpu->arch.pvsched.base = gpa; - val = SMCCC_RET_SUCCESS; + val[0] = SMCCC_RET_SUCCESS; } break; case ARM_SMCCC_HV_PV_SCHED_IPA_RELEASE: vcpu->arch.pvsched.base = GPA_INVALID; - val = SMCCC_RET_SUCCESS; + val[0] = SMCCC_RET_SUCCESS; break; case ARM_SMCCC_HV_PV_SCHED_KICK_CPU: - val = kvm_pvsched_kick_vcpu(vcpu); + val[0] = kvm_pvsched_kick_vcpu(vcpu); break; case ARM_SMCCC_TRNG_VERSION: case ARM_SMCCC_TRNG_FEATURES: @@ -113,6 +175,6 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) return kvm_psci_call(vcpu); } - smccc_set_retval(vcpu, val, 0, 0, 0); + smccc_set_retval(vcpu, val[0], val[1], val[2], val[3]); return 1; } diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 96197e8f6b933af29324ff5d99d7f37ead2a7880..3cc8c7d4c7dfea31380e209e72a350ddd8b81275 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include #include @@ -24,6 +25,8 @@ #include #include #include +#include +#include #include #include @@ -222,6 +225,7 @@ static u64 arch_counter_read_cc(const struct cyclecounter *cc) static struct clocksource clocksource_counter = { .name = "arch_sys_counter", + .id = CSID_ARM_ARCH_COUNTER, .rating = 400, .read = arch_counter_read, .flags = CLOCK_SOURCE_IS_CONTINUOUS, @@ -1721,3 +1725,35 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table) } TIMER_ACPI_DECLARE(arch_timer, ACPI_SIG_GTDT, arch_timer_acpi_init); #endif + +int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *ts, + struct clocksource **cs) +{ + struct arm_smccc_res hvc_res; + u32 ptp_counter; + ktime_t ktime; + + if (!IS_ENABLED(CONFIG_HAVE_ARM_SMCCC_DISCOVERY)) + return -EOPNOTSUPP; + + if (arch_timer_uses_ppi == ARCH_TIMER_VIRT_PPI) + ptp_counter = KVM_PTP_VIRT_COUNTER; + else + ptp_counter = KVM_PTP_PHYS_COUNTER; + + arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID, + ptp_counter, &hvc_res); + + if ((int)(hvc_res.a0) < 0) + return -EOPNOTSUPP; + + ktime = (u64)hvc_res.a0 << 32 | hvc_res.a1; + *ts = ktime_to_timespec64(ktime); + if (cycle) + *cycle = (u64)hvc_res.a2 << 32 | hvc_res.a3; + if (cs) + *cs = &clocksource_counter; + + return 0; +} +EXPORT_SYMBOL_GPL(kvm_arch_ptp_get_crosststamp); diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c index 151d00898cabbfaa3f841b6db214cc3442a49374..fdf0f36e29edcda46765b5fff1f03b5e4e1306e0 100644 --- a/drivers/firmware/psci/psci.c +++ b/drivers/firmware/psci/psci.c @@ -23,6 +23,7 @@ #include #include +#include #include #include #include @@ -472,6 +473,7 @@ static int __init psci_probe(void) psci_init_cpu_suspend(); psci_init_system_suspend(); psci_init_system_reset2(); + kvm_init_hyp_services(); } return 0; diff --git a/drivers/firmware/smccc/Makefile b/drivers/firmware/smccc/Makefile index 72ab840428324292e790aad95756a82aaf371a9f..40d19144a860724bd7fadd652ddbadf737a28695 100644 --- a/drivers/firmware/smccc/Makefile +++ b/drivers/firmware/smccc/Makefile @@ -1,4 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 # -obj-$(CONFIG_HAVE_ARM_SMCCC_DISCOVERY) += smccc.o +obj-$(CONFIG_HAVE_ARM_SMCCC_DISCOVERY) += smccc.o kvm_guest.o obj-$(CONFIG_ARM_SMCCC_SOC_ID) += soc_id.o diff --git a/drivers/firmware/smccc/kvm_guest.c b/drivers/firmware/smccc/kvm_guest.c new file mode 100644 index 0000000000000000000000000000000000000000..2d3e866decaa671f3cf28e6d74de24d390ef5b86 --- /dev/null +++ b/drivers/firmware/smccc/kvm_guest.c @@ -0,0 +1,50 @@ +// SPDX-License-Identifier: GPL-2.0 + +#define pr_fmt(fmt) "smccc: KVM: " fmt + +#include +#include +#include +#include + +#include + +static DECLARE_BITMAP(__kvm_arm_hyp_services, ARM_SMCCC_KVM_NUM_FUNCS) __ro_after_init = { }; + +void __init kvm_init_hyp_services(void) +{ + struct arm_smccc_res res; + u32 val[4]; + + if (arm_smccc_1_1_get_conduit() != SMCCC_CONDUIT_HVC) + return; + + arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID, &res); + if (res.a0 != ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_0 || + res.a1 != ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_1 || + res.a2 != ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_2 || + res.a3 != ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_3) + return; + + memset(&res, 0, sizeof(res)); + arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID, &res); + + val[0] = lower_32_bits(res.a0); + val[1] = lower_32_bits(res.a1); + val[2] = lower_32_bits(res.a2); + val[3] = lower_32_bits(res.a3); + + bitmap_from_arr32(__kvm_arm_hyp_services, val, ARM_SMCCC_KVM_NUM_FUNCS); + + pr_info("hypervisor services detected (0x%08lx 0x%08lx 0x%08lx 0x%08lx)\n", + res.a3, res.a2, res.a1, res.a0); +} + +bool kvm_arm_hyp_service_available(u32 func_id) +{ + if (func_id >= ARM_SMCCC_KVM_NUM_FUNCS) + return false; + + return test_bit(func_id, __kvm_arm_hyp_services); +} +EXPORT_SYMBOL_GPL(kvm_arm_hyp_service_available); diff --git a/drivers/firmware/smccc/smccc.c b/drivers/firmware/smccc/smccc.c index 6a6a5b0700a862a226edc28f926c6da5ef177ac7..9f937b125ab076ac0bcc2cd95b3250d918e7ae0e 100644 --- a/drivers/firmware/smccc/smccc.c +++ b/drivers/firmware/smccc/smccc.c @@ -8,6 +8,7 @@ #include #include #include +#include #include static u32 smccc_version = ARM_SMCCC_VERSION_1_0; diff --git a/drivers/ptp/Kconfig b/drivers/ptp/Kconfig index cf64c3e8fb86022366b359bb23d54e7ad838a70c..e834648d141c5b58722b07cd2941fee0ad74b6a9 100644 --- a/drivers/ptp/Kconfig +++ b/drivers/ptp/Kconfig @@ -109,7 +109,7 @@ config PTP_1588_CLOCK_PCH config PTP_1588_CLOCK_KVM tristate "KVM virtual PTP clock" depends on PTP_1588_CLOCK - depends on KVM_GUEST && X86 + depends on (KVM_GUEST && X86) || (HAVE_ARM_SMCCC_DISCOVERY && ARM_ARCH_TIMER) default y help This driver adds support for using kvm infrastructure as a PTP diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile index 9344b879daba92ef2084ec32be7cf5d85d6e1e2e..67e260be595b8ef3cee9e30082449ea4d55e92bc 100644 --- a/drivers/ptp/Makefile +++ b/drivers/ptp/Makefile @@ -4,6 +4,8 @@ # ptp-y := ptp_clock.o ptp_chardev.o ptp_sysfs.o +ptp_kvm-$(CONFIG_X86) := ptp_kvm_x86.o ptp_kvm_common.o +ptp_kvm-$(CONFIG_HAVE_ARM_SMCCC) := ptp_kvm_arm.o ptp_kvm_common.o obj-$(CONFIG_PTP_1588_CLOCK) += ptp.o obj-$(CONFIG_PTP_1588_CLOCK_DTE) += ptp_dte.o obj-$(CONFIG_PTP_1588_CLOCK_INES) += ptp_ines.o diff --git a/drivers/ptp/ptp_kvm_arm.c b/drivers/ptp/ptp_kvm_arm.c new file mode 100644 index 0000000000000000000000000000000000000000..b7d28c8dfb84e37df45f2dc4def7c2c11e1efa08 --- /dev/null +++ b/drivers/ptp/ptp_kvm_arm.c @@ -0,0 +1,28 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Virtual PTP 1588 clock for use with KVM guests + * Copyright (C) 2019 ARM Ltd. + * All Rights Reserved + */ + +#include +#include + +#include +#include + +int kvm_arch_ptp_init(void) +{ + int ret; + + ret = kvm_arm_hyp_service_available(ARM_SMCCC_KVM_FUNC_PTP); + if (ret <= 0) + return -EOPNOTSUPP; + + return 0; +} + +int kvm_arch_ptp_get_clock(struct timespec64 *ts) +{ + return kvm_arch_ptp_get_crosststamp(NULL, ts, NULL); +} diff --git a/drivers/ptp/ptp_kvm.c b/drivers/ptp/ptp_kvm_common.c similarity index 60% rename from drivers/ptp/ptp_kvm.c rename to drivers/ptp/ptp_kvm_common.c index 658d33fc31952f732bd7715441984215f6b3bea0..fcae32f56f25a2d23807a5d1fdd643e1804fbbf4 100644 --- a/drivers/ptp/ptp_kvm.c +++ b/drivers/ptp/ptp_kvm_common.c @@ -8,11 +8,11 @@ #include #include #include +#include #include +#include #include #include -#include -#include #include #include @@ -24,56 +24,29 @@ struct kvm_ptp_clock { static DEFINE_SPINLOCK(kvm_ptp_lock); -static struct pvclock_vsyscall_time_info *hv_clock; - -static struct kvm_clock_pairing clock_pair; -static phys_addr_t clock_pair_gpa; - static int ptp_kvm_get_time_fn(ktime_t *device_time, struct system_counterval_t *system_counter, void *ctx) { - unsigned long ret; + long ret; + u64 cycle; struct timespec64 tspec; - unsigned version; - int cpu; - struct pvclock_vcpu_time_info *src; + struct clocksource *cs; spin_lock(&kvm_ptp_lock); preempt_disable_notrace(); - cpu = smp_processor_id(); - src = &hv_clock[cpu].pvti; - - do { - /* - * We are using a TSC value read in the hosts - * kvm_hc_clock_pairing handling. - * So any changes to tsc_to_system_mul - * and tsc_shift or any other pvclock - * data invalidate that measurement. - */ - version = pvclock_read_begin(src); - - ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, - clock_pair_gpa, - KVM_CLOCK_PAIRING_WALLCLOCK); - if (ret != 0) { - pr_err_ratelimited("clock pairing hypercall ret %lu\n", ret); - spin_unlock(&kvm_ptp_lock); - preempt_enable_notrace(); - return -EOPNOTSUPP; - } - - tspec.tv_sec = clock_pair.sec; - tspec.tv_nsec = clock_pair.nsec; - ret = __pvclock_read_cycles(src, clock_pair.tsc); - } while (pvclock_read_retry(src, version)); + ret = kvm_arch_ptp_get_crosststamp(&cycle, &tspec, &cs); + if (ret) { + spin_unlock(&kvm_ptp_lock); + preempt_enable_notrace(); + return ret; + } preempt_enable_notrace(); - system_counter->cycles = ret; - system_counter->cs = &kvm_clock; + system_counter->cycles = cycle; + system_counter->cs = cs; *device_time = timespec64_to_ktime(tspec); @@ -111,22 +84,17 @@ static int ptp_kvm_settime(struct ptp_clock_info *ptp, static int ptp_kvm_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts) { - unsigned long ret; + long ret; struct timespec64 tspec; spin_lock(&kvm_ptp_lock); - ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, - clock_pair_gpa, - KVM_CLOCK_PAIRING_WALLCLOCK); - if (ret != 0) { - pr_err_ratelimited("clock offset hypercall ret %lu\n", ret); + ret = kvm_arch_ptp_get_clock(&tspec); + if (ret) { spin_unlock(&kvm_ptp_lock); - return -EOPNOTSUPP; + return ret; } - tspec.tv_sec = clock_pair.sec; - tspec.tv_nsec = clock_pair.nsec; spin_unlock(&kvm_ptp_lock); memcpy(ts, &tspec, sizeof(struct timespec64)); @@ -168,19 +136,12 @@ static int __init ptp_kvm_init(void) { long ret; - if (!kvm_para_available()) - return -ENODEV; - - clock_pair_gpa = slow_virt_to_phys(&clock_pair); - hv_clock = pvclock_get_pvti_cpu0_va(); - - if (!hv_clock) - return -ENODEV; - - ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, clock_pair_gpa, - KVM_CLOCK_PAIRING_WALLCLOCK); - if (ret == -KVM_ENOSYS || ret == -KVM_EOPNOTSUPP) - return -ENODEV; + ret = kvm_arch_ptp_init(); + if (ret) { + if (ret != -EOPNOTSUPP) + pr_err("fail to initialize ptp_kvm"); + return ret; + } kvm_ptp_clock.caps = ptp_kvm_caps; diff --git a/drivers/ptp/ptp_kvm_x86.c b/drivers/ptp/ptp_kvm_x86.c new file mode 100644 index 0000000000000000000000000000000000000000..38ebb3f953af70140208d4634a03d0f4bc1d9459 --- /dev/null +++ b/drivers/ptp/ptp_kvm_x86.c @@ -0,0 +1,97 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Virtual PTP 1588 clock for use with KVM guests + * + * Copyright (C) 2017 Red Hat Inc. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct pvclock_vsyscall_time_info *hv_clock; + +static phys_addr_t clock_pair_gpa; +static struct kvm_clock_pairing clock_pair; + +int kvm_arch_ptp_init(void) +{ + long ret; + + if (!kvm_para_available()) + return -ENODEV; + + clock_pair_gpa = slow_virt_to_phys(&clock_pair); + hv_clock = pvclock_get_pvti_cpu0_va(); + if (!hv_clock) + return -ENODEV; + + ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, clock_pair_gpa, + KVM_CLOCK_PAIRING_WALLCLOCK); + if (ret == -KVM_ENOSYS) + return -ENODEV; + + return ret; +} + +int kvm_arch_ptp_get_clock(struct timespec64 *ts) +{ + long ret; + + ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, + clock_pair_gpa, + KVM_CLOCK_PAIRING_WALLCLOCK); + if (ret != 0) { + pr_err_ratelimited("clock offset hypercall ret %lu\n", ret); + return -EOPNOTSUPP; + } + + ts->tv_sec = clock_pair.sec; + ts->tv_nsec = clock_pair.nsec; + + return 0; +} + +int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *tspec, + struct clocksource **cs) +{ + struct pvclock_vcpu_time_info *src; + unsigned int version; + long ret; + int cpu; + + cpu = smp_processor_id(); + src = &hv_clock[cpu].pvti; + + do { + /* + * We are using a TSC value read in the hosts + * kvm_hc_clock_pairing handling. + * So any changes to tsc_to_system_mul + * and tsc_shift or any other pvclock + * data invalidate that measurement. + */ + version = pvclock_read_begin(src); + + ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, + clock_pair_gpa, + KVM_CLOCK_PAIRING_WALLCLOCK); + if (ret != 0) { + pr_err_ratelimited("clock pairing hypercall ret %lu\n", ret); + return -EOPNOTSUPP; + } + tspec->tv_sec = clock_pair.sec; + tspec->tv_nsec = clock_pair.nsec; + *cycle = __pvclock_read_cycles(src, clock_pair.tsc); + } while (pvclock_read_retry(src, version)); + + *cs = &kvm_clock; + + return 0; +} diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h index 9b1ddf9905f8ab5a52742ccc3f34fef8810a483d..9e50a386ec8f368f7e62c49b34276df3b3085e29 100644 --- a/include/linux/arm-smccc.h +++ b/include/linux/arm-smccc.h @@ -55,6 +55,8 @@ #define ARM_SMCCC_OWNER_TRUSTED_OS 50 #define ARM_SMCCC_OWNER_TRUSTED_OS_END 63 +#define ARM_SMCCC_FUNC_QUERY_CALL_UID 0xff01 + #define ARM_SMCCC_QUIRK_NONE 0 #define ARM_SMCCC_QUIRK_QCOM_A6 1 /* Save/restore register a6 */ @@ -95,8 +97,47 @@ ARM_SMCCC_SMC_32, \ 0, 0x3fff) +#define ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_VENDOR_HYP, \ + ARM_SMCCC_FUNC_QUERY_CALL_UID) + +/* KVM UID value: 28b46fb6-2ec5-11e9-a9ca-4b564d003a74 */ +#define ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_0 0xb66fb428U +#define ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_1 0xe911c52eU +#define ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_2 0x564bcaa9U +#define ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_3 0x743a004dU + +/* KVM "vendor specific" services */ +#define ARM_SMCCC_KVM_FUNC_FEATURES 0 +#define ARM_SMCCC_KVM_FUNC_PTP 1 +#define ARM_SMCCC_KVM_FUNC_FEATURES_2 127 +#define ARM_SMCCC_KVM_NUM_FUNCS 128 + +#define ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_VENDOR_HYP, \ + ARM_SMCCC_KVM_FUNC_FEATURES) + #define SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED 1 +/* + * ptp_kvm is a feature used for time sync between vm and host. + * ptp_kvm module in guest kernel will get service from host using + * this hypercall ID. + */ +#define ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_VENDOR_HYP, \ + ARM_SMCCC_KVM_FUNC_PTP) + +/* ptp_kvm counter type ID */ +#define KVM_PTP_VIRT_COUNTER 0 +#define KVM_PTP_PHYS_COUNTER 1 + /* Paravirtualised time calls (defined by ARM DEN0057A) */ #define ARM_SMCCC_HV_PV_TIME_FEATURES \ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 4c3ecccc44ed3c2d85ce5468fc12cf65fa4279ed..ee06239194aa4b3fb71e8942f15e09ca94812376 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -17,6 +17,7 @@ #include #include #include +#include #include #include @@ -62,6 +63,10 @@ struct module; * 400-499: Perfect * The ideal clocksource. A must-use where * available. + * @id: Defaults to CSID_GENERIC. The id value is captured + * in certain snapshot functions to allow callers to + * validate the clocksource from which the snapshot was + * taken. * @flags: Flags describing special properties * @enable: Optional function to enable the clocksource * @disable: Optional function to disable the clocksource @@ -93,6 +98,7 @@ struct clocksource { u32 shift; u64 max_idle_ns; u32 maxadj; + KABI_FILL_HOLE(enum clocksource_ids id) #ifdef CONFIG_ARCH_CLOCKSOURCE_DATA struct arch_clocksource_data archdata; #endif diff --git a/include/linux/clocksource_ids.h b/include/linux/clocksource_ids.h new file mode 100644 index 0000000000000000000000000000000000000000..16775d7d8f8d64197fd59dfc716de1df9d1d9768 --- /dev/null +++ b/include/linux/clocksource_ids.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_CLOCKSOURCE_IDS_H +#define _LINUX_CLOCKSOURCE_IDS_H + +/* Enum to give clocksources a unique identifier */ +enum clocksource_ids { + CSID_GENERIC = 0, + CSID_ARM_ARCH_COUNTER, + CSID_MAX, +}; + +#endif diff --git a/include/linux/ptp_kvm.h b/include/linux/ptp_kvm.h new file mode 100644 index 0000000000000000000000000000000000000000..f960a719f0d5414994cce9c02de88547ba8c011e --- /dev/null +++ b/include/linux/ptp_kvm.h @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Virtual PTP 1588 clock for use with KVM guests + * + * Copyright (C) 2017 Red Hat Inc. + */ + +#ifndef _PTP_KVM_H_ +#define _PTP_KVM_H_ + +struct timespec64; +struct clocksource; + +int kvm_arch_ptp_init(void); +int kvm_arch_ptp_get_clock(struct timespec64 *ts); +int kvm_arch_ptp_get_crosststamp(u64 *cycle, + struct timespec64 *tspec, struct clocksource **cs); + +#endif /* _PTP_KVM_H_ */ diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index 7f7e4a3f4394a201231cc643ec77a220ba6720d3..16666d1eace034f317173c5534c77806ab80321c 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -3,6 +3,7 @@ #define _LINUX_TIMEKEEPING_H #include +#include /* Included from linux/ktime.h */ @@ -244,11 +245,14 @@ struct ktime_timestamps { * @cs_was_changed_seq: The sequence number of clocksource change events */ struct system_time_snapshot { - u64 cycles; - ktime_t real; - ktime_t raw; - unsigned int clock_was_set_seq; - u8 cs_was_changed_seq; + u64 cycles; + ktime_t real; + ktime_t raw; + unsigned int clock_was_set_seq; + u8 cs_was_changed_seq; +#ifndef __GENKSYMS__ + short cs_id; +#endif }; /** diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 90b2e4a3198d34e56a3048dc9910eb132253d9aa..a2a831fedaab17602cc90633074f3144758f2c77 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -1088,6 +1088,7 @@ struct kvm_ppc_resize_hpt { #define KVM_CAP_ENFORCE_PV_FEATURE_CPUID 190 #define KVM_CAP_X86_BUS_LOCK_EXIT 193 #define KVM_CAP_SGX_ATTRIBUTE 196 +#define KVM_CAP_PTP_KVM 198 #define KVM_CAP_XSAVE2 208 #define KVM_CAP_SYS_ATTRIBUTES 209 #define KVM_CAP_X86_TRIPLE_FAULT_EVENT 218 diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 74492f08660c4da4696458a7e9d21e50961bc653..1657b5e74c64cf9efd44a220dc38a4a6512e3226 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -1029,6 +1029,8 @@ int __clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq) clocksource_arch_init(cs); + if (WARN_ON_ONCE((unsigned int)cs->id >= CSID_MAX)) + cs->id = CSID_GENERIC; if (cs->vdso_clock_mode < 0 || cs->vdso_clock_mode >= VDSO_CLOCKMODE_MAX) { pr_warn("clocksource %s registered with invalid VDSO mode %d. Disabling VDSO support.\n", diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index c8d9b89a7571fe71466f757f100976b651f5f950..e10e22f092cc920736d343025b3f952e0c0d139c 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -1065,6 +1065,7 @@ void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot) do { seq = read_seqcount_begin(&tk_core.seq); now = tk_clock_read(&tk->tkr_mono); + systime_snapshot->cs_id = (short)tk->tkr_mono.clock->id; systime_snapshot->cs_was_changed_seq = tk->cs_was_changed_seq; systime_snapshot->clock_was_set_seq = tk->clock_was_set_seq; base_real = ktime_add(tk->tkr_mono.base,