diff options
| -rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 4 | ||||
| -rw-r--r-- | arch/arm64/include/uapi/asm/kvm.h | 9 | ||||
| -rw-r--r-- | arch/arm64/kvm/arch_timer.c | 54 | ||||
| -rw-r--r-- | arch/arm64/kvm/arm.c | 8 | ||||
| -rw-r--r-- | include/uapi/linux/kvm.h | 3 |
5 files changed, 73 insertions, 5 deletions
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 002a10cbade2..116233a390e9 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -221,6 +221,8 @@ struct kvm_arch { #define KVM_ARCH_FLAG_EL1_32BIT 4 /* PSCI SYSTEM_SUSPEND enabled for the guest */ #define KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED 5 + /* VM counter offset */ +#define KVM_ARCH_FLAG_VM_COUNTER_OFFSET 6 unsigned long flags; @@ -1010,6 +1012,8 @@ int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu, long kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm, struct kvm_arm_copy_mte_tags *copy_tags); +int kvm_vm_ioctl_set_counter_offset(struct kvm *kvm, + struct kvm_arm_counter_offset *offset); /* Guest/host FPSIMD coordination helpers */ int kvm_arch_vcpu_run_map_fp(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index f8129c624b07..12fb0d8a760a 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -198,6 +198,15 @@ struct kvm_arm_copy_mte_tags { __u64 reserved[2]; }; +/* + * Counter/Timer offset structure. Describe the virtual/physical offset. + * To be used with KVM_ARM_SET_COUNTER_OFFSET. + */ +struct kvm_arm_counter_offset { + __u64 counter_offset; + __u64 reserved; +}; + #define KVM_ARM_TAGS_TO_GUEST 0 #define KVM_ARM_TAGS_FROM_GUEST 1 diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c index bb64a71ae193..771504c79711 100644 --- a/arch/arm64/kvm/arch_timer.c +++ b/arch/arm64/kvm/arch_timer.c @@ -851,9 +851,11 @@ void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu) ptimer->vcpu = vcpu; ptimer->offset.vm_offset = &vcpu->kvm->arch.timer_data.poffset; - /* Synchronize cntvoff across all vtimers of a VM. */ - timer_set_offset(vtimer, kvm_phys_timer_read()); - timer_set_offset(ptimer, 0); + /* Synchronize offsets across timers of a VM if not already provided */ + if (!test_bit(KVM_ARCH_FLAG_VM_COUNTER_OFFSET, &vcpu->kvm->arch.flags)) { + timer_set_offset(vtimer, kvm_phys_timer_read()); + timer_set_offset(ptimer, 0); + } hrtimer_init(&timer->bg_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD); timer->bg_timer.function = kvm_bg_timer_expire; @@ -897,8 +899,11 @@ int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value) kvm_arm_timer_write(vcpu, timer, TIMER_REG_CTL, value); break; case KVM_REG_ARM_TIMER_CNT: - timer = vcpu_vtimer(vcpu); - timer_set_offset(timer, kvm_phys_timer_read() - value); + if (!test_bit(KVM_ARCH_FLAG_VM_COUNTER_OFFSET, + &vcpu->kvm->arch.flags)) { + timer = vcpu_vtimer(vcpu); + timer_set_offset(timer, kvm_phys_timer_read() - value); + } break; case KVM_REG_ARM_TIMER_CVAL: timer = vcpu_vtimer(vcpu); @@ -908,6 +913,13 @@ int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value) timer = vcpu_ptimer(vcpu); kvm_arm_timer_write(vcpu, timer, TIMER_REG_CTL, value); break; + case KVM_REG_ARM_PTIMER_CNT: + if (!test_bit(KVM_ARCH_FLAG_VM_COUNTER_OFFSET, + &vcpu->kvm->arch.flags)) { + timer = vcpu_ptimer(vcpu); + timer_set_offset(timer, kvm_phys_timer_read() - value); + } + break; case KVM_REG_ARM_PTIMER_CVAL: timer = vcpu_ptimer(vcpu); kvm_arm_timer_write(vcpu, timer, TIMER_REG_CVAL, value); @@ -1443,3 +1455,35 @@ int kvm_arm_timer_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) return -ENXIO; } + +int kvm_vm_ioctl_set_counter_offset(struct kvm *kvm, + struct kvm_arm_counter_offset *offset) +{ + int ret = 0; + + if (offset->reserved) + return -EINVAL; + + mutex_lock(&kvm->lock); + + if (lock_all_vcpus(kvm)) { + set_bit(KVM_ARCH_FLAG_VM_COUNTER_OFFSET, &kvm->arch.flags); + + /* + * If userspace decides to set the offset using this + * API rather than merely restoring the counter + * values, the offset applies to both the virtual and + * physical views. + */ + kvm->arch.timer_data.voffset = offset->counter_offset; + kvm->arch.timer_data.poffset = offset->counter_offset; + + unlock_all_vcpus(kvm); + } else { + ret = -EBUSY; + } + + mutex_unlock(&kvm->lock); + + return ret; +} diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index ae5110cc3bad..1c8a4bbae684 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -220,6 +220,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_VCPU_ATTRIBUTES: case KVM_CAP_PTP_KVM: case KVM_CAP_ARM_SYSTEM_SUSPEND: + case KVM_CAP_COUNTER_OFFSET: r = 1; break; case KVM_CAP_SET_GUEST_DEBUG2: @@ -1479,6 +1480,13 @@ long kvm_arch_vm_ioctl(struct file *filp, return -EFAULT; return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags); } + case KVM_ARM_SET_COUNTER_OFFSET: { + struct kvm_arm_counter_offset offset; + + if (copy_from_user(&offset, argp, sizeof(offset))) + return -EFAULT; + return kvm_vm_ioctl_set_counter_offset(kvm, &offset); + } default: return -EINVAL; } diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index d77aef872a0a..6a7e1a0ecf04 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -1184,6 +1184,7 @@ struct kvm_ppc_resize_hpt { #define KVM_CAP_S390_PROTECTED_ASYNC_DISABLE 224 #define KVM_CAP_DIRTY_LOG_RING_WITH_BITMAP 225 #define KVM_CAP_PMU_EVENT_MASKED_EVENTS 226 +#define KVM_CAP_COUNTER_OFFSET 227 #ifdef KVM_CAP_IRQ_ROUTING @@ -1543,6 +1544,8 @@ struct kvm_s390_ucas_mapping { #define KVM_SET_PMU_EVENT_FILTER _IOW(KVMIO, 0xb2, struct kvm_pmu_event_filter) #define KVM_PPC_SVM_OFF _IO(KVMIO, 0xb3) #define KVM_ARM_MTE_COPY_TAGS _IOR(KVMIO, 0xb4, struct kvm_arm_copy_mte_tags) +/* Available with KVM_CAP_COUNTER_OFFSET */ +#define KVM_ARM_SET_COUNTER_OFFSET _IOW(KVMIO, 0xb5, struct kvm_arm_counter_offset) /* ioctl for vm fd */ #define KVM_CREATE_DEVICE _IOWR(KVMIO, 0xe0, struct kvm_create_device) |