diff options
Diffstat (limited to 'arch/arm64/kvm/arm.c')
| -rw-r--r-- | arch/arm64/kvm/arm.c | 2674 |
1 files changed, 2674 insertions, 0 deletions
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c new file mode 100644 index 000000000000..3dee5490eea9 --- /dev/null +++ b/arch/arm64/kvm/arm.c @@ -0,0 +1,2674 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2012 - Virtual Open Systems and Columbia University + * Author: Christoffer Dall <c.dall@virtualopensystems.com> + */ + +#include <linux/bug.h> +#include <linux/cpu_pm.h> +#include <linux/entry-kvm.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/kvm_host.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/vmalloc.h> +#include <linux/fs.h> +#include <linux/mman.h> +#include <linux/sched.h> +#include <linux/kvm.h> +#include <linux/kvm_irqfd.h> +#include <linux/irqbypass.h> +#include <linux/sched/stat.h> +#include <linux/psci.h> +#include <trace/events/kvm.h> + +#define CREATE_TRACE_POINTS +#include "trace_arm.h" + +#include <linux/uaccess.h> +#include <asm/ptrace.h> +#include <asm/mman.h> +#include <asm/tlbflush.h> +#include <asm/cacheflush.h> +#include <asm/cpufeature.h> +#include <asm/virt.h> +#include <asm/kvm_arm.h> +#include <asm/kvm_asm.h> +#include <asm/kvm_mmu.h> +#include <asm/kvm_nested.h> +#include <asm/kvm_pkvm.h> +#include <asm/kvm_emulate.h> +#include <asm/sections.h> + +#include <kvm/arm_hypercalls.h> +#include <kvm/arm_pmu.h> +#include <kvm/arm_psci.h> + +static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT; + +DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector); + +DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page); +DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params); + +DECLARE_KVM_NVHE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt); + +static bool vgic_present, kvm_arm_initialised; + +static DEFINE_PER_CPU(unsigned char, kvm_hyp_initialized); +DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use); + +bool is_kvm_arm_initialised(void) +{ + return kvm_arm_initialised; +} + +int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu) +{ + return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE; +} + +int kvm_vm_ioctl_enable_cap(struct kvm *kvm, + struct kvm_enable_cap *cap) +{ + int r; + u64 new_cap; + + if (cap->flags) + return -EINVAL; + + switch (cap->cap) { + case KVM_CAP_ARM_NISV_TO_USER: + r = 0; + set_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER, + &kvm->arch.flags); + break; + case KVM_CAP_ARM_MTE: + mutex_lock(&kvm->lock); + if (!system_supports_mte() || kvm->created_vcpus) { + r = -EINVAL; + } else { + r = 0; + set_bit(KVM_ARCH_FLAG_MTE_ENABLED, &kvm->arch.flags); + } + mutex_unlock(&kvm->lock); + break; + case KVM_CAP_ARM_SYSTEM_SUSPEND: + r = 0; + set_bit(KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED, &kvm->arch.flags); + break; + case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE: + new_cap = cap->args[0]; + + mutex_lock(&kvm->slots_lock); + /* + * To keep things simple, allow changing the chunk + * size only when no memory slots have been created. + */ + if (!kvm_are_all_memslots_empty(kvm)) { + r = -EINVAL; + } else if (new_cap && !kvm_is_block_size_supported(new_cap)) { + r = -EINVAL; + } else { + r = 0; + kvm->arch.mmu.split_page_chunk_size = new_cap; + } + mutex_unlock(&kvm->slots_lock); + break; + default: + r = -EINVAL; + break; + } + + return r; +} + +static int kvm_arm_default_max_vcpus(void) +{ + return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS; +} + +/** + * kvm_arch_init_vm - initializes a VM data structure + * @kvm: pointer to the KVM struct + */ +int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) +{ + int ret; + + mutex_init(&kvm->arch.config_lock); + +#ifdef CONFIG_LOCKDEP + /* Clue in lockdep that the config_lock must be taken inside kvm->lock */ + mutex_lock(&kvm->lock); + mutex_lock(&kvm->arch.config_lock); + mutex_unlock(&kvm->arch.config_lock); + mutex_unlock(&kvm->lock); +#endif + + ret = kvm_share_hyp(kvm, kvm + 1); + if (ret) + return ret; + + ret = pkvm_init_host_vm(kvm); + if (ret) + goto err_unshare_kvm; + + if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL_ACCOUNT)) { + ret = -ENOMEM; + goto err_unshare_kvm; + } + cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask); + + ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu, type); + if (ret) + goto err_free_cpumask; + + kvm_vgic_early_init(kvm); + + kvm_timer_init_vm(kvm); + + /* The maximum number of VCPUs is limited by the host's GIC model */ + kvm->max_vcpus = kvm_arm_default_max_vcpus(); + + kvm_arm_init_hypercalls(kvm); + + bitmap_zero(kvm->arch.vcpu_features, KVM_VCPU_MAX_FEATURES); + + return 0; + +err_free_cpumask: + free_cpumask_var(kvm->arch.supported_cpus); +err_unshare_kvm: + kvm_unshare_hyp(kvm, kvm + 1); + return ret; +} + +vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) +{ + return VM_FAULT_SIGBUS; +} + +void kvm_arch_create_vm_debugfs(struct kvm *kvm) +{ + kvm_sys_regs_create_debugfs(kvm); +} + +/** + * kvm_arch_destroy_vm - destroy the VM data structure + * @kvm: pointer to the KVM struct + */ +void kvm_arch_destroy_vm(struct kvm *kvm) +{ + bitmap_free(kvm->arch.pmu_filter); + free_cpumask_var(kvm->arch.supported_cpus); + + kvm_vgic_destroy(kvm); + + if (is_protected_kvm_enabled()) + pkvm_destroy_hyp_vm(kvm); + + kfree(kvm->arch.mpidr_data); + kfree(kvm->arch.sysreg_masks); + kvm_destroy_vcpus(kvm); + + kvm_unshare_hyp(kvm, kvm + 1); + + kvm_arm_teardown_hypercalls(kvm); +} + +int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) +{ + int r; + switch (ext) { + case KVM_CAP_IRQCHIP: + r = vgic_present; + break; + case KVM_CAP_IOEVENTFD: + case KVM_CAP_USER_MEMORY: + case KVM_CAP_SYNC_MMU: + case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: + case KVM_CAP_ONE_REG: + case KVM_CAP_ARM_PSCI: + case KVM_CAP_ARM_PSCI_0_2: + case KVM_CAP_READONLY_MEM: + case KVM_CAP_MP_STATE: + case KVM_CAP_IMMEDIATE_EXIT: + case KVM_CAP_VCPU_EVENTS: + case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2: + case KVM_CAP_ARM_NISV_TO_USER: + case KVM_CAP_ARM_INJECT_EXT_DABT: + case KVM_CAP_SET_GUEST_DEBUG: + case KVM_CAP_VCPU_ATTRIBUTES: + case KVM_CAP_PTP_KVM: + case KVM_CAP_ARM_SYSTEM_SUSPEND: + case KVM_CAP_IRQFD_RESAMPLE: + case KVM_CAP_COUNTER_OFFSET: + r = 1; + break; + case KVM_CAP_SET_GUEST_DEBUG2: + return KVM_GUESTDBG_VALID_MASK; + case KVM_CAP_ARM_SET_DEVICE_ADDR: + r = 1; + break; + case KVM_CAP_NR_VCPUS: + /* + * ARM64 treats KVM_CAP_NR_CPUS differently from all other + * architectures, as it does not always bound it to + * KVM_CAP_MAX_VCPUS. It should not matter much because + * this is just an advisory value. + */ + r = min_t(unsigned int, num_online_cpus(), + kvm_arm_default_max_vcpus()); + break; + case KVM_CAP_MAX_VCPUS: + case KVM_CAP_MAX_VCPU_ID: + if (kvm) + r = kvm->max_vcpus; + else + r = kvm_arm_default_max_vcpus(); + break; + case KVM_CAP_MSI_DEVID: + if (!kvm) + r = -EINVAL; + else + r = kvm->arch.vgic.msis_require_devid; + break; + case KVM_CAP_ARM_USER_IRQ: + /* + * 1: EL1_VTIMER, EL1_PTIMER, and PMU. + * (bump this number if adding more devices) + */ + r = 1; + break; + case KVM_CAP_ARM_MTE: + r = system_supports_mte(); + break; + case KVM_CAP_STEAL_TIME: + r = kvm_arm_pvtime_supported(); + break; + case KVM_CAP_ARM_EL1_32BIT: + r = cpus_have_final_cap(ARM64_HAS_32BIT_EL1); + break; + case KVM_CAP_GUEST_DEBUG_HW_BPS: + r = get_num_brps(); + break; + case KVM_CAP_GUEST_DEBUG_HW_WPS: + r = get_num_wrps(); + break; + case KVM_CAP_ARM_PMU_V3: + r = kvm_arm_support_pmu_v3(); + break; + case KVM_CAP_ARM_INJECT_SERROR_ESR: + r = cpus_have_final_cap(ARM64_HAS_RAS_EXTN); + break; + case KVM_CAP_ARM_VM_IPA_SIZE: + r = get_kvm_ipa_limit(); + break; + case KVM_CAP_ARM_SVE: + r = system_supports_sve(); + break; + case KVM_CAP_ARM_PTRAUTH_ADDRESS: + case KVM_CAP_ARM_PTRAUTH_GENERIC: + r = system_has_full_ptr_auth(); + break; + case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE: + if (kvm) + r = kvm->arch.mmu.split_page_chunk_size; + else + r = KVM_ARM_EAGER_SPLIT_CHUNK_SIZE_DEFAULT; + break; + case KVM_CAP_ARM_SUPPORTED_BLOCK_SIZES: + r = kvm_supported_block_sizes(); + break; + case KVM_CAP_ARM_SUPPORTED_REG_MASK_RANGES: + r = BIT(0); + break; + default: + r = 0; + } + + return r; +} + +long kvm_arch_dev_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + return -EINVAL; +} + +struct kvm *kvm_arch_alloc_vm(void) +{ + size_t sz = sizeof(struct kvm); + + if (!has_vhe()) + return kzalloc(sz, GFP_KERNEL_ACCOUNT); + + return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO); +} + +int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id) +{ + if (irqchip_in_kernel(kvm) && vgic_initialized(kvm)) + return -EBUSY; + + if (id >= kvm->max_vcpus) + return -EINVAL; + + return 0; +} + +int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) +{ + int err; + + spin_lock_init(&vcpu->arch.mp_state_lock); + +#ifdef CONFIG_LOCKDEP + /* Inform lockdep that the config_lock is acquired after vcpu->mutex */ + mutex_lock(&vcpu->mutex); + mutex_lock(&vcpu->kvm->arch.config_lock); + mutex_unlock(&vcpu->kvm->arch.config_lock); + mutex_unlock(&vcpu->mutex); +#endif + + /* Force users to call KVM_ARM_VCPU_INIT */ + vcpu_clear_flag(vcpu, VCPU_INITIALIZED); + + vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO; + + /* + * Default value for the FP state, will be overloaded at load + * time if we support FP (pretty likely) + */ + vcpu->arch.fp_state = FP_STATE_FREE; + + /* Set up the timer */ + kvm_timer_vcpu_init(vcpu); + + kvm_pmu_vcpu_init(vcpu); + + kvm_arm_reset_debug_ptr(vcpu); + + kvm_arm_pvtime_vcpu_init(&vcpu->arch); + + vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu; + + err = kvm_vgic_vcpu_init(vcpu); + if (err) + return err; + + return kvm_share_hyp(vcpu, vcpu + 1); +} + +void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) +{ +} + +void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) +{ + if (vcpu_has_run_once(vcpu) && unlikely(!irqchip_in_kernel(vcpu->kvm))) + static_branch_dec(&userspace_irqchip_in_use); + + kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); + kvm_timer_vcpu_terminate(vcpu); + kvm_pmu_vcpu_destroy(vcpu); + kvm_vgic_vcpu_destroy(vcpu); + kvm_arm_vcpu_destroy(vcpu); +} + +void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) +{ + +} + +void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) +{ + +} + +void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) +{ + struct kvm_s2_mmu *mmu; + int *last_ran; + + mmu = vcpu->arch.hw_mmu; + last_ran = this_cpu_ptr(mmu->last_vcpu_ran); + + /* + * We guarantee that both TLBs and I-cache are private to each + * vcpu. If detecting that a vcpu from the same VM has + * previously run on the same physical CPU, call into the + * hypervisor code to nuke the relevant contexts. + * + * We might get preempted before the vCPU actually runs, but + * over-invalidation doesn't affect correctness. + */ + if (*last_ran != vcpu->vcpu_idx) { + kvm_call_hyp(__kvm_flush_cpu_context, mmu); + *last_ran = vcpu->vcpu_idx; + } + + vcpu->cpu = cpu; + + kvm_vgic_load(vcpu); + kvm_timer_vcpu_load(vcpu); + if (has_vhe()) + kvm_vcpu_load_vhe(vcpu); + kvm_arch_vcpu_load_fp(vcpu); + kvm_vcpu_pmu_restore_guest(vcpu); + if (kvm_arm_is_pvtime_enabled(&vcpu->arch)) + kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu); + + if (single_task_running()) + vcpu_clear_wfx_traps(vcpu); + else + vcpu_set_wfx_traps(vcpu); + + if (vcpu_has_ptrauth(vcpu)) + vcpu_ptrauth_disable(vcpu); + kvm_arch_vcpu_load_debug_state_flags(vcpu); + + if (!cpumask_test_cpu(cpu, vcpu->kvm->arch.supported_cpus)) + vcpu_set_on_unsupported_cpu(vcpu); +} + +void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) +{ + kvm_arch_vcpu_put_debug_state_flags(vcpu); + kvm_arch_vcpu_put_fp(vcpu); + if (has_vhe()) + kvm_vcpu_put_vhe(vcpu); + kvm_timer_vcpu_put(vcpu); + kvm_vgic_put(vcpu); + kvm_vcpu_pmu_restore_host(vcpu); + kvm_arm_vmid_clear_active(); + + vcpu_clear_on_unsupported_cpu(vcpu); + vcpu->cpu = -1; +} + +static void __kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu) +{ + WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_STOPPED); + kvm_make_request(KVM_REQ_SLEEP, vcpu); + kvm_vcpu_kick(vcpu); +} + +void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu) +{ + spin_lock(&vcpu->arch.mp_state_lock); + __kvm_arm_vcpu_power_off(vcpu); + spin_unlock(&vcpu->arch.mp_state_lock); +} + +bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu) +{ + return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_STOPPED; +} + +static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu) +{ + WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_SUSPENDED); + kvm_make_request(KVM_REQ_SUSPEND, vcpu); + kvm_vcpu_kick(vcpu); +} + +static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu) +{ + return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_SUSPENDED; +} + +int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state) +{ + *mp_state = READ_ONCE(vcpu->arch.mp_state); + + return 0; +} + +int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state) +{ + int ret = 0; + + spin_lock(&vcpu->arch.mp_state_lock); + + switch (mp_state->mp_state) { + case KVM_MP_STATE_RUNNABLE: + WRITE_ONCE(vcpu->arch.mp_state, *mp_state); + break; + case KVM_MP_STATE_STOPPED: + __kvm_arm_vcpu_power_off(vcpu); + break; + case KVM_MP_STATE_SUSPENDED: + kvm_arm_vcpu_suspend(vcpu); + break; + default: + ret = -EINVAL; + } + + spin_unlock(&vcpu->arch.mp_state_lock); + + return ret; +} + +/** + * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled + * @v: The VCPU pointer + * + * If the guest CPU is not waiting for interrupts or an interrupt line is + * asserted, the CPU is by definition runnable. + */ +int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) +{ + bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF); + return ((irq_lines || kvm_vgic_vcpu_pending_irq(v)) + && !kvm_arm_vcpu_stopped(v) && !v->arch.pause); +} + +bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) +{ + return vcpu_mode_priv(vcpu); +} + +#ifdef CONFIG_GUEST_PERF_EVENTS +unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu) +{ + return *vcpu_pc(vcpu); +} +#endif + +static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu) +{ + return vcpu_get_flag(vcpu, VCPU_INITIALIZED); +} + +static void kvm_init_mpidr_data(struct kvm *kvm) +{ + struct kvm_mpidr_data *data = NULL; + unsigned long c, mask, nr_entries; + u64 aff_set = 0, aff_clr = ~0UL; + struct kvm_vcpu *vcpu; + + mutex_lock(&kvm->arch.config_lock); + + if (kvm->arch.mpidr_data || atomic_read(&kvm->online_vcpus) == 1) + goto out; + + kvm_for_each_vcpu(c, vcpu, kvm) { + u64 aff = kvm_vcpu_get_mpidr_aff(vcpu); + aff_set |= aff; + aff_clr &= aff; + } + + /* + * A significant bit can be either 0 or 1, and will only appear in + * aff_set. Use aff_clr to weed out the useless stuff. + */ + mask = aff_set ^ aff_clr; + nr_entries = BIT_ULL(hweight_long(mask)); + + /* + * Don't let userspace fool us. If we need more than a single page + * to describe the compressed MPIDR array, just fall back to the + * iterative method. Single vcpu VMs do not need this either. + */ + if (struct_size(data, cmpidr_to_idx, nr_entries) <= PAGE_SIZE) + data = kzalloc(struct_size(data, cmpidr_to_idx, nr_entries), + GFP_KERNEL_ACCOUNT); + + if (!data) + goto out; + + data->mpidr_mask = mask; + + kvm_for_each_vcpu(c, vcpu, kvm) { + u64 aff = kvm_vcpu_get_mpidr_aff(vcpu); + u16 index = kvm_mpidr_index(data, aff); + + data->cmpidr_to_idx[index] = c; + } + + kvm->arch.mpidr_data = data; +out: + mutex_unlock(&kvm->arch.config_lock); +} + +/* + * Handle both the initialisation that is being done when the vcpu is + * run for the first time, as well as the updates that must be + * performed each time we get a new thread dealing with this vcpu. + */ +int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu) +{ + struct kvm *kvm = vcpu->kvm; + int ret; + + if (!kvm_vcpu_initialized(vcpu)) + return -ENOEXEC; + + if (!kvm_arm_vcpu_is_finalized(vcpu)) + return -EPERM; + + ret = kvm_arch_vcpu_run_map_fp(vcpu); + if (ret) + return ret; + + if (likely(vcpu_has_run_once(vcpu))) + return 0; + + kvm_init_mpidr_data(kvm); + + kvm_arm_vcpu_init_debug(vcpu); + + if (likely(irqchip_in_kernel(kvm))) { + /* + * Map the VGIC hardware resources before running a vcpu the + * first time on this VM. + */ + ret = kvm_vgic_map_resources(kvm); + if (ret) + return ret; + } + + if (vcpu_has_nv(vcpu)) { + ret = kvm_init_nv_sysregs(vcpu->kvm); + if (ret) + return ret; + } + + /* + * This needs to happen after NV has imposed its own restrictions on + * the feature set + */ + kvm_init_sysreg(vcpu); + + ret = kvm_timer_enable(vcpu); + if (ret) + return ret; + + ret = kvm_arm_pmu_v3_enable(vcpu); + if (ret) + return ret; + + if (is_protected_kvm_enabled()) { + ret = pkvm_create_hyp_vm(kvm); + if (ret) + return ret; + } + + if (!irqchip_in_kernel(kvm)) { + /* + * Tell the rest of the code that there are userspace irqchip + * VMs in the wild. + */ + static_branch_inc(&userspace_irqchip_in_use); + } + + /* + * Initialize traps for protected VMs. + * NOTE: Move to run in EL2 directly, rather than via a hypercall, once + * the code is in place for first run initialization at EL2. + */ + if (kvm_vm_is_protected(kvm)) + kvm_call_hyp_nvhe(__pkvm_vcpu_init_traps, vcpu); + + mutex_lock(&kvm->arch.config_lock); + set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags); + mutex_unlock(&kvm->arch.config_lock); + + return ret; +} + +bool kvm_arch_intc_initialized(struct kvm *kvm) +{ + return vgic_initialized(kvm); +} + +void kvm_arm_halt_guest(struct kvm *kvm) +{ + unsigned long i; + struct kvm_vcpu *vcpu; + + kvm_for_each_vcpu(i, vcpu, kvm) + vcpu->arch.pause = true; + kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP); +} + +void kvm_arm_resume_guest(struct kvm *kvm) +{ + unsigned long i; + struct kvm_vcpu *vcpu; + + kvm_for_each_vcpu(i, vcpu, kvm) { + vcpu->arch.pause = false; + __kvm_vcpu_wake_up(vcpu); + } +} + +static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu) +{ + struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu); + + rcuwait_wait_event(wait, + (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause), + TASK_INTERRUPTIBLE); + + if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) { + /* Awaken to handle a signal, request we sleep again later. */ + kvm_make_request(KVM_REQ_SLEEP, vcpu); + } + + /* + * Make sure we will observe a potential reset request if we've + * observed a change to the power state. Pairs with the smp_wmb() in + * kvm_psci_vcpu_on(). + */ + smp_rmb(); +} + +/** + * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior + * @vcpu: The VCPU pointer + * + * Suspend execution of a vCPU until a valid wake event is detected, i.e. until + * the vCPU is runnable. The vCPU may or may not be scheduled out, depending + * on when a wake event arrives, e.g. there may already be a pending wake event. + */ +void kvm_vcpu_wfi(struct kvm_vcpu *vcpu) +{ + /* + * Sync back the state of the GIC CPU interface so that we have + * the latest PMR and group enables. This ensures that + * kvm_arch_vcpu_runnable has up-to-date data to decide whether + * we have pending interrupts, e.g. when determining if the + * vCPU should block. + * + * For the same reason, we want to tell GICv4 that we need + * doorbells to be signalled, should an interrupt become pending. + */ + preempt_disable(); + kvm_vgic_vmcr_sync(vcpu); + vcpu_set_flag(vcpu, IN_WFI); + vgic_v4_put(vcpu); + preempt_enable(); + + kvm_vcpu_halt(vcpu); + vcpu_clear_flag(vcpu, IN_WFIT); + + preempt_disable(); + vcpu_clear_flag(vcpu, IN_WFI); + vgic_v4_load(vcpu); + preempt_enable(); +} + +static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu) +{ + if (!kvm_arm_vcpu_suspended(vcpu)) + return 1; + + kvm_vcpu_wfi(vcpu); + + /* + * The suspend state is sticky; we do not leave it until userspace + * explicitly marks the vCPU as runnable. Request that we suspend again + * later. + */ + kvm_make_request(KVM_REQ_SUSPEND, vcpu); + + /* + * Check to make sure the vCPU is actually runnable. If so, exit to + * userspace informing it of the wakeup condition. + */ + if (kvm_arch_vcpu_runnable(vcpu)) { + memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event)); + vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP; + vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; + return 0; + } + + /* + * Otherwise, we were unblocked to process a different event, such as a + * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to + * process the event. + */ + return 1; +} + +/** + * check_vcpu_requests - check and handle pending vCPU requests + * @vcpu: the VCPU pointer + * + * Return: 1 if we should enter the guest + * 0 if we should exit to userspace + * < 0 if we should exit to userspace, where the return value indicates + * an error + */ +static int check_vcpu_requests(struct kvm_vcpu *vcpu) +{ + if (kvm_request_pending(vcpu)) { + if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) + kvm_vcpu_sleep(vcpu); + + if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) + kvm_reset_vcpu(vcpu); + + /* + * Clear IRQ_PENDING requests that were made to guarantee + * that a VCPU sees new virtual interrupts. + */ + kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu); + + if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu)) + kvm_update_stolen_time(vcpu); + + if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) { + /* The distributor enable bits were changed */ + preempt_disable(); + vgic_v4_put(vcpu); + vgic_v4_load(vcpu); + preempt_enable(); + } + + if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu)) + kvm_vcpu_reload_pmu(vcpu); + + if (kvm_check_request(KVM_REQ_RESYNC_PMU_EL0, vcpu)) + kvm_vcpu_pmu_restore_guest(vcpu); + + if (kvm_check_request(KVM_REQ_SUSPEND, vcpu)) + return kvm_vcpu_suspend(vcpu); + + if (kvm_dirty_ring_check_request(vcpu)) + return 0; + } + + return 1; +} + +static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu) +{ + if (likely(!vcpu_mode_is_32bit(vcpu))) + return false; + + if (vcpu_has_nv(vcpu)) + return true; + + return !kvm_supports_32bit_el0(); +} + +/** + * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest + * @vcpu: The VCPU pointer + * @ret: Pointer to write optional return code + * + * Returns: true if the VCPU needs to return to a preemptible + interruptible + * and skip guest entry. + * + * This function disambiguates between two different types of exits: exits to a + * preemptible + interruptible kernel context and exits to userspace. For an + * exit to userspace, this function will write the return code to ret and return + * true. For an exit to preemptible + interruptible kernel context (i.e. check + * for pending work and re-enter), return true without writing to ret. + */ +static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret) +{ + struct kvm_run *run = vcpu->run; + + /* + * If we're using a userspace irqchip, then check if we need + * to tell a userspace irqchip about timer or PMU level + * changes and if so, exit to userspace (the actual level + * state gets updated in kvm_timer_update_run and + * kvm_pmu_update_run below). + */ + if (static_branch_unlikely(&userspace_irqchip_in_use)) { + if (kvm_timer_should_notify_user(vcpu) || + kvm_pmu_should_notify_user(vcpu)) { + *ret = -EINTR; + run->exit_reason = KVM_EXIT_INTR; + return true; + } + } + + if (unlikely(vcpu_on_unsupported_cpu(vcpu))) { + run->exit_reason = KVM_EXIT_FAIL_ENTRY; + run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED; + run->fail_entry.cpu = smp_processor_id(); + *ret = 0; + return true; + } + + return kvm_request_pending(vcpu) || + xfer_to_guest_mode_work_pending(); +} + +/* + * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while + * the vCPU is running. + * + * This must be noinstr as instrumentation may make use of RCU, and this is not + * safe during the EQS. + */ +static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu) +{ + int ret; + + guest_state_enter_irqoff(); + ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu); + guest_state_exit_irqoff(); + + return ret; +} + +/** + * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code + * @vcpu: The VCPU pointer + * + * This function is called through the VCPU_RUN ioctl called from user space. It + * will execute VM code in a loop until the time slice for the process is used + * or some emulation is needed from user space in which case the function will + * return with return value 0 and with the kvm_run structure filled in with the + * required data for the requested emulation. + */ +int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) +{ + struct kvm_run *run = vcpu->run; + int ret; + + if (run->exit_reason == KVM_EXIT_MMIO) { + ret = kvm_handle_mmio_return(vcpu); + if (ret) + return ret; + } + + vcpu_load(vcpu); + + if (run->immediate_exit) { + ret = -EINTR; + goto out; + } + + kvm_sigset_activate(vcpu); + + ret = 1; + run->exit_reason = KVM_EXIT_UNKNOWN; + run->flags = 0; + while (ret > 0) { + /* + * Check conditions before entering the guest + */ + ret = xfer_to_guest_mode_handle_work(vcpu); + if (!ret) + ret = 1; + + if (ret > 0) + ret = check_vcpu_requests(vcpu); + + /* + * Preparing the interrupts to be injected also + * involves poking the GIC, which must be done in a + * non-preemptible context. + */ + preempt_disable(); + + /* + * The VMID allocator only tracks active VMIDs per + * physical CPU, and therefore the VMID allocated may not be + * preserved on VMID roll-over if the task was preempted, + * making a thread's VMID inactive. So we need to call + * kvm_arm_vmid_update() in non-premptible context. + */ + if (kvm_arm_vmid_update(&vcpu->arch.hw_mmu->vmid) && + has_vhe()) + __load_stage2(vcpu->arch.hw_mmu, + vcpu->arch.hw_mmu->arch); + + kvm_pmu_flush_hwstate(vcpu); + + local_irq_disable(); + + kvm_vgic_flush_hwstate(vcpu); + + kvm_pmu_update_vcpu_events(vcpu); + + /* + * Ensure we set mode to IN_GUEST_MODE after we disable + * interrupts and before the final VCPU requests check. + * See the comment in kvm_vcpu_exiting_guest_mode() and + * Documentation/virt/kvm/vcpu-requests.rst + */ + smp_store_mb(vcpu->mode, IN_GUEST_MODE); + + if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) { + vcpu->mode = OUTSIDE_GUEST_MODE; + isb(); /* Ensure work in x_flush_hwstate is committed */ + kvm_pmu_sync_hwstate(vcpu); + if (static_branch_unlikely(&userspace_irqchip_in_use)) + kvm_timer_sync_user(vcpu); + kvm_vgic_sync_hwstate(vcpu); + local_irq_enable(); + preempt_enable(); + continue; + } + + kvm_arm_setup_debug(vcpu); + kvm_arch_vcpu_ctxflush_fp(vcpu); + + /************************************************************** + * Enter the guest + */ + trace_kvm_entry(*vcpu_pc(vcpu)); + guest_timing_enter_irqoff(); + + ret = kvm_arm_vcpu_enter_exit(vcpu); + + vcpu->mode = OUTSIDE_GUEST_MODE; + vcpu->stat.exits++; + /* + * Back from guest + *************************************************************/ + + kvm_arm_clear_debug(vcpu); + + /* + * We must sync the PMU state before the vgic state so + * that the vgic can properly sample the updated state of the + * interrupt line. + */ + kvm_pmu_sync_hwstate(vcpu); + + /* + * Sync the vgic state before syncing the timer state because + * the timer code needs to know if the virtual timer + * interrupts are active. + */ + kvm_vgic_sync_hwstate(vcpu); + + /* + * Sync the timer hardware state before enabling interrupts as + * we don't want vtimer interrupts to race with syncing the + * timer virtual interrupt state. + */ + if (static_branch_unlikely(&userspace_irqchip_in_use)) + kvm_timer_sync_user(vcpu); + + kvm_arch_vcpu_ctxsync_fp(vcpu); + + /* + * We must ensure that any pending interrupts are taken before + * we exit guest timing so that timer ticks are accounted as + * guest time. Transiently unmask interrupts so that any + * pending interrupts are taken. + * + * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other + * context synchronization event) is necessary to ensure that + * pending interrupts are taken. + */ + if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) { + local_irq_enable(); + isb(); + local_irq_disable(); + } + + guest_timing_exit_irqoff(); + + local_irq_enable(); + + trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); + + /* Exit types that need handling before we can be preempted */ + handle_exit_early(vcpu, ret); + + preempt_enable(); + + /* + * The ARMv8 architecture doesn't give the hypervisor + * a mechanism to prevent a guest from dropping to AArch32 EL0 + * if implemented by the CPU. If we spot the guest in such + * state and that we decided it wasn't supposed to do so (like + * with the asymmetric AArch32 case), return to userspace with + * a fatal error. + */ + if (vcpu_mode_is_bad_32bit(vcpu)) { + /* + * As we have caught the guest red-handed, decide that + * it isn't fit for purpose anymore by making the vcpu + * invalid. The VMM can try and fix it by issuing a + * KVM_ARM_VCPU_INIT if it really wants to. + */ + vcpu_clear_flag(vcpu, VCPU_INITIALIZED); + ret = ARM_EXCEPTION_IL; + } + + ret = handle_exit(vcpu, ret); + } + + /* Tell userspace about in-kernel device output levels */ + if (unlikely(!irqchip_in_kernel(vcpu->kvm))) { + kvm_timer_update_run(vcpu); + kvm_pmu_update_run(vcpu); + } + + kvm_sigset_deactivate(vcpu); + +out: + /* + * In the unlikely event that we are returning to userspace + * with pending exceptions or PC adjustment, commit these + * adjustments in order to give userspace a consistent view of + * the vcpu state. Note that this relies on __kvm_adjust_pc() + * being preempt-safe on VHE. + */ + if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) || + vcpu_get_flag(vcpu, INCREMENT_PC))) + kvm_call_hyp(__kvm_adjust_pc, vcpu); + + vcpu_put(vcpu); + return ret; +} + +static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level) +{ + int bit_index; + bool set; + unsigned long *hcr; + + if (number == KVM_ARM_IRQ_CPU_IRQ) + bit_index = __ffs(HCR_VI); + else /* KVM_ARM_IRQ_CPU_FIQ */ + bit_index = __ffs(HCR_VF); + + hcr = vcpu_hcr(vcpu); + if (level) + set = test_and_set_bit(bit_index, hcr); + else + set = test_and_clear_bit(bit_index, hcr); + + /* + * If we didn't change anything, no need to wake up or kick other CPUs + */ + if (set == level) + return 0; + + /* + * The vcpu irq_lines field was updated, wake up sleeping VCPUs and + * trigger a world-switch round on the running physical CPU to set the + * virtual IRQ/FIQ fields in the HCR appropriately. + */ + kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); + kvm_vcpu_kick(vcpu); + + return 0; +} + +int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level, + bool line_status) +{ + u32 irq = irq_level->irq; + unsigned int irq_type, vcpu_id, irq_num; + struct kvm_vcpu *vcpu = NULL; + bool level = irq_level->level; + + irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK; + vcpu_id = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK; + vcpu_id += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1); + irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK; + + trace_kvm_irq_line(irq_type, vcpu_id, irq_num, irq_level->level); + + switch (irq_type) { + case KVM_ARM_IRQ_TYPE_CPU: + if (irqchip_in_kernel(kvm)) + return -ENXIO; + + vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id); + if (!vcpu) + return -EINVAL; + + if (irq_num > KVM_ARM_IRQ_CPU_FIQ) + return -EINVAL; + + return vcpu_interrupt_line(vcpu, irq_num, level); + case KVM_ARM_IRQ_TYPE_PPI: + if (!irqchip_in_kernel(kvm)) + return -ENXIO; + + vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id); + if (!vcpu) + return -EINVAL; + + if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS) + return -EINVAL; + + return kvm_vgic_inject_irq(kvm, vcpu, irq_num, level, NULL); + case KVM_ARM_IRQ_TYPE_SPI: + if (!irqchip_in_kernel(kvm)) + return -ENXIO; + + if (irq_num < VGIC_NR_PRIVATE_IRQS) + return -EINVAL; + + return kvm_vgic_inject_irq(kvm, NULL, irq_num, level, NULL); + } + + return -EINVAL; +} + +static unsigned long system_supported_vcpu_features(void) +{ + unsigned long features = KVM_VCPU_VALID_FEATURES; + + if (!cpus_have_final_cap(ARM64_HAS_32BIT_EL1)) + clear_bit(KVM_ARM_VCPU_EL1_32BIT, &features); + + if (!kvm_arm_support_pmu_v3()) + clear_bit(KVM_ARM_VCPU_PMU_V3, &features); + + if (!system_supports_sve()) + clear_bit(KVM_ARM_VCPU_SVE, &features); + + if (!system_has_full_ptr_auth()) { + clear_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, &features); + clear_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, &features); + } + + if (!cpus_have_final_cap(ARM64_HAS_NESTED_VIRT)) + clear_bit(KVM_ARM_VCPU_HAS_EL2, &features); + + return features; +} + +static int kvm_vcpu_init_check_features(struct kvm_vcpu *vcpu, + const struct kvm_vcpu_init *init) +{ + unsigned long features = init->features[0]; + int i; + + if (features & ~KVM_VCPU_VALID_FEATURES) + return -ENOENT; + + for (i = 1; i < ARRAY_SIZE(init->features); i++) { + if (init->features[i]) + return -ENOENT; + } + + if (features & ~system_supported_vcpu_features()) + return -EINVAL; + + /* + * For now make sure that both address/generic pointer authentication + * features are requested by the userspace together. + */ + if (test_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, &features) != + test_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, &features)) + return -EINVAL; + + /* Disallow NV+SVE for the time being */ + if (test_bit(KVM_ARM_VCPU_HAS_EL2, &features) && + test_bit(KVM_ARM_VCPU_SVE, &features)) + return -EINVAL; + + if (!test_bit(KVM_ARM_VCPU_EL1_32BIT, &features)) + return 0; + + /* MTE is incompatible with AArch32 */ + if (kvm_has_mte(vcpu->kvm)) + return -EINVAL; + + /* NV is incompatible with AArch32 */ + if (test_bit(KVM_ARM_VCPU_HAS_EL2, &features)) + return -EINVAL; + + return 0; +} + +static bool kvm_vcpu_init_changed(struct kvm_vcpu *vcpu, + const struct kvm_vcpu_init *init) +{ + unsigned long features = init->features[0]; + + return !bitmap_equal(vcpu->kvm->arch.vcpu_features, &features, + KVM_VCPU_MAX_FEATURES); +} + +static int kvm_setup_vcpu(struct kvm_vcpu *vcpu) +{ + struct kvm *kvm = vcpu->kvm; + int ret = 0; + + /* + * When the vCPU has a PMU, but no PMU is set for the guest + * yet, set the default one. + */ + if (kvm_vcpu_has_pmu(vcpu) && !kvm->arch.arm_pmu) + ret = kvm_arm_set_default_pmu(kvm); + + return ret; +} + +static int __kvm_vcpu_set_target(struct kvm_vcpu *vcpu, + const struct kvm_vcpu_init *init) +{ + unsigned long features = init->features[0]; + struct kvm *kvm = vcpu->kvm; + int ret = -EINVAL; + + mutex_lock(&kvm->arch.config_lock); + + if (test_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags) && + kvm_vcpu_init_changed(vcpu, init)) + goto out_unlock; + + bitmap_copy(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES); + + ret = kvm_setup_vcpu(vcpu); + if (ret) + goto out_unlock; + + /* Now we know what it is, we can reset it. */ + kvm_reset_vcpu(vcpu); + + set_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags); + vcpu_set_flag(vcpu, VCPU_INITIALIZED); + ret = 0; +out_unlock: + mutex_unlock(&kvm->arch.config_lock); + return ret; +} + +static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu, + const struct kvm_vcpu_init *init) +{ + int ret; + + if (init->target != KVM_ARM_TARGET_GENERIC_V8 && + init->target != kvm_target_cpu()) + return -EINVAL; + + ret = kvm_vcpu_init_check_features(vcpu, init); + if (ret) + return ret; + + if (!kvm_vcpu_initialized(vcpu)) + return __kvm_vcpu_set_target(vcpu, init); + + if (kvm_vcpu_init_changed(vcpu, init)) + return -EINVAL; + + kvm_reset_vcpu(vcpu); + return 0; +} + +static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, + struct kvm_vcpu_init *init) +{ + bool power_off = false; + int ret; + + /* + * Treat the power-off vCPU feature as ephemeral. Clear the bit to avoid + * reflecting it in the finalized feature set, thus limiting its scope + * to a single KVM_ARM_VCPU_INIT call. + */ + if (init->features[0] & BIT(KVM_ARM_VCPU_POWER_OFF)) { + init->features[0] &= ~BIT(KVM_ARM_VCPU_POWER_OFF); + power_off = true; + } + + ret = kvm_vcpu_set_target(vcpu, init); + if (ret) + return ret; + + /* + * Ensure a rebooted VM will fault in RAM pages and detect if the + * guest MMU is turned off and flush the caches as needed. + * + * S2FWB enforces all memory accesses to RAM being cacheable, + * ensuring that the data side is always coherent. We still + * need to invalidate the I-cache though, as FWB does *not* + * imply CTR_EL0.DIC. + */ + if (vcpu_has_run_once(vcpu)) { + if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB)) + stage2_unmap_vm(vcpu->kvm); + else + icache_inval_all_pou(); + } + + vcpu_reset_hcr(vcpu); + vcpu->arch.cptr_el2 = kvm_get_reset_cptr_el2(vcpu); + + /* + * Handle the "start in power-off" case. + */ + spin_lock(&vcpu->arch.mp_state_lock); + + if (power_off) + __kvm_arm_vcpu_power_off(vcpu); + else + WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE); + + spin_unlock(&vcpu->arch.mp_state_lock); + + return 0; +} + +static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu, + struct kvm_device_attr *attr) +{ + int ret = -ENXIO; + + switch (attr->group) { + default: + ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr); + break; + } + + return ret; +} + +static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu, + struct kvm_device_attr *attr) +{ + int ret = -ENXIO; + + switch (attr->group) { + default: + ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr); + break; + } + + return ret; +} + +static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu, + struct kvm_device_attr *attr) +{ + int ret = -ENXIO; + + switch (attr->group) { + default: + ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr); + break; + } + + return ret; +} + +static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu, + struct kvm_vcpu_events *events) +{ + memset(events, 0, sizeof(*events)); + + return __kvm_arm_vcpu_get_events(vcpu, events); +} + +static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, + struct kvm_vcpu_events *events) +{ + int i; + + /* check whether the reserved field is zero */ + for (i = 0; i < ARRAY_SIZE(events->reserved); i++) + if (events->reserved[i]) + return -EINVAL; + + /* check whether the pad field is zero */ + for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++) + if (events->exception.pad[i]) + return -EINVAL; + + return __kvm_arm_vcpu_set_events(vcpu, events); +} + +long kvm_arch_vcpu_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + struct kvm_vcpu *vcpu = filp->private_data; + void __user *argp = (void __user *)arg; + struct kvm_device_attr attr; + long r; + + switch (ioctl) { + case KVM_ARM_VCPU_INIT: { + struct kvm_vcpu_init init; + + r = -EFAULT; + if (copy_from_user(&init, argp, sizeof(init))) + break; + + r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init); + break; + } + case KVM_SET_ONE_REG: + case KVM_GET_ONE_REG: { + struct kvm_one_reg reg; + + r = -ENOEXEC; + if (unlikely(!kvm_vcpu_initialized(vcpu))) + break; + + r = -EFAULT; + if (copy_from_user(®, argp, sizeof(reg))) + break; + + /* + * We could owe a reset due to PSCI. Handle the pending reset + * here to ensure userspace register accesses are ordered after + * the reset. + */ + if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) + kvm_reset_vcpu(vcpu); + + if (ioctl == KVM_SET_ONE_REG) + r = kvm_arm_set_reg(vcpu, ®); + else + r = kvm_arm_get_reg(vcpu, ®); + break; + } + case KVM_GET_REG_LIST: { + struct kvm_reg_list __user *user_list = argp; + struct kvm_reg_list reg_list; + unsigned n; + + r = -ENOEXEC; + if (unlikely(!kvm_vcpu_initialized(vcpu))) + break; + + r = -EPERM; + if (!kvm_arm_vcpu_is_finalized(vcpu)) + break; + + r = -EFAULT; + if (copy_from_user(®_list, user_list, sizeof(reg_list))) + break; + n = reg_list.n; + reg_list.n = kvm_arm_num_regs(vcpu); + if (copy_to_user(user_list, ®_list, sizeof(reg_list))) + break; + r = -E2BIG; + if (n < reg_list.n) + break; + r = kvm_arm_copy_reg_indices(vcpu, user_list->reg); + break; + } + case KVM_SET_DEVICE_ATTR: { + r = -EFAULT; + if (copy_from_user(&attr, argp, sizeof(attr))) + break; + r = kvm_arm_vcpu_set_attr(vcpu, &attr); + break; + } + case KVM_GET_DEVICE_ATTR: { + r = -EFAULT; + if (copy_from_user(&attr, argp, sizeof(attr))) + break; + r = kvm_arm_vcpu_get_attr(vcpu, &attr); + break; + } + case KVM_HAS_DEVICE_ATTR: { + r = -EFAULT; + if (copy_from_user(&attr, argp, sizeof(attr))) + break; + r = kvm_arm_vcpu_has_attr(vcpu, &attr); + break; + } + case KVM_GET_VCPU_EVENTS: { + struct kvm_vcpu_events events; + + if (kvm_arm_vcpu_get_events(vcpu, &events)) + return -EINVAL; + + if (copy_to_user(argp, &events, sizeof(events))) + return -EFAULT; + + return 0; + } + case KVM_SET_VCPU_EVENTS: { + struct kvm_vcpu_events events; + + if (copy_from_user(&events, argp, sizeof(events))) + return -EFAULT; + + return kvm_arm_vcpu_set_events(vcpu, &events); + } + case KVM_ARM_VCPU_FINALIZE: { + int what; + + if (!kvm_vcpu_initialized(vcpu)) + return -ENOEXEC; + + if (get_user(what, (const int __user *)argp)) + return -EFAULT; + + return kvm_arm_vcpu_finalize(vcpu, what); + } + default: + r = -EINVAL; + } + + return r; +} + +void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) +{ + +} + +static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm, + struct kvm_arm_device_addr *dev_addr) +{ + switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) { + case KVM_ARM_DEVICE_VGIC_V2: + if (!vgic_present) + return -ENXIO; + return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr); + default: + return -ENODEV; + } +} + +static int kvm_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr) +{ + switch (attr->group) { + case KVM_ARM_VM_SMCCC_CTRL: + return kvm_vm_smccc_has_attr(kvm, attr); + default: + return -ENXIO; + } +} + +static int kvm_vm_set_attr(struct kvm *kvm, struct kvm_device_attr *attr) +{ + switch (attr->group) { + case KVM_ARM_VM_SMCCC_CTRL: + return kvm_vm_smccc_set_attr(kvm, attr); + default: + return -ENXIO; + } +} + +int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) +{ + struct kvm *kvm = filp->private_data; + void __user *argp = (void __user *)arg; + struct kvm_device_attr attr; + + switch (ioctl) { + case KVM_CREATE_IRQCHIP: { + int ret; + if (!vgic_present) + return -ENXIO; + mutex_lock(&kvm->lock); + ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2); + mutex_unlock(&kvm->lock); + return ret; + } + case KVM_ARM_SET_DEVICE_ADDR: { + struct kvm_arm_device_addr dev_addr; + + if (copy_from_user(&dev_addr, argp, sizeof(dev_addr))) + return -EFAULT; + return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr); + } + case KVM_ARM_PREFERRED_TARGET: { + struct kvm_vcpu_init init = { + .target = KVM_ARM_TARGET_GENERIC_V8, + }; + + if (copy_to_user(argp, &init, sizeof(init))) + return -EFAULT; + + return 0; + } + case KVM_ARM_MTE_COPY_TAGS: { + struct kvm_arm_copy_mte_tags copy_tags; + + if (copy_from_user(©_tags, argp, sizeof(copy_tags))) + 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); + } + case KVM_HAS_DEVICE_ATTR: { + if (copy_from_user(&attr, argp, sizeof(attr))) + return -EFAULT; + + return kvm_vm_has_attr(kvm, &attr); + } + case KVM_SET_DEVICE_ATTR: { + if (copy_from_user(&attr, argp, sizeof(attr))) + return -EFAULT; + + return kvm_vm_set_attr(kvm, &attr); + } + case KVM_ARM_GET_REG_WRITABLE_MASKS: { + struct reg_mask_range range; + + if (copy_from_user(&range, argp, sizeof(range))) + return -EFAULT; + return kvm_vm_ioctl_get_reg_writable_masks(kvm, &range); + } + default: + return -EINVAL; + } +} + +/* unlocks vcpus from @vcpu_lock_idx and smaller */ +static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx) +{ + struct kvm_vcpu *tmp_vcpu; + + for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) { + tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx); + mutex_unlock(&tmp_vcpu->mutex); + } +} + +void unlock_all_vcpus(struct kvm *kvm) +{ + lockdep_assert_held(&kvm->lock); + + unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1); +} + +/* Returns true if all vcpus were locked, false otherwise */ +bool lock_all_vcpus(struct kvm *kvm) +{ + struct kvm_vcpu *tmp_vcpu; + unsigned long c; + + lockdep_assert_held(&kvm->lock); + + /* + * Any time a vcpu is in an ioctl (including running), the + * core KVM code tries to grab the vcpu->mutex. + * + * By grabbing the vcpu->mutex of all VCPUs we ensure that no + * other VCPUs can fiddle with the state while we access it. + */ + kvm_for_each_vcpu(c, tmp_vcpu, kvm) { + if (!mutex_trylock(&tmp_vcpu->mutex)) { + unlock_vcpus(kvm, c - 1); + return false; + } + } + + return true; +} + +static unsigned long nvhe_percpu_size(void) +{ + return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) - + (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start); +} + +static unsigned long nvhe_percpu_order(void) +{ + unsigned long size = nvhe_percpu_size(); + + return size ? get_order(size) : 0; +} + +/* A lookup table holding the hypervisor VA for each vector slot */ +static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS]; + +static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot) +{ + hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot); +} + +static int kvm_init_vector_slots(void) +{ + int err; + void *base; + + base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector)); + kvm_init_vector_slot(base, HYP_VECTOR_DIRECT); + + base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs)); + kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT); + + if (kvm_system_needs_idmapped_vectors() && + !is_protected_kvm_enabled()) { + err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs), + __BP_HARDEN_HYP_VECS_SZ, &base); + if (err) + return err; + } + + kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT); + kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT); + return 0; +} + +static void __init cpu_prepare_hyp_mode(int cpu, u32 hyp_va_bits) +{ + struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); + u64 mmfr0 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); + unsigned long tcr; + + /* + * Calculate the raw per-cpu offset without a translation from the + * kernel's mapping to the linear mapping, and store it in tpidr_el2 + * so that we can use adr_l to access per-cpu variables in EL2. + * Also drop the KASAN tag which gets in the way... + */ + params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) - + (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start)); + + params->mair_el2 = read_sysreg(mair_el1); + + tcr = read_sysreg(tcr_el1); + if (cpus_have_final_cap(ARM64_KVM_HVHE)) { + tcr |= TCR_EPD1_MASK; + } else { + tcr &= TCR_EL2_MASK; + tcr |= TCR_EL2_RES1; + } + tcr &= ~TCR_T0SZ_MASK; + tcr |= TCR_T0SZ(hyp_va_bits); + tcr &= ~TCR_EL2_PS_MASK; + tcr |= FIELD_PREP(TCR_EL2_PS_MASK, kvm_get_parange(mmfr0)); + if (kvm_lpa2_is_enabled()) + tcr |= TCR_EL2_DS; + params->tcr_el2 = tcr; + + params->pgd_pa = kvm_mmu_get_httbr(); + if (is_protected_kvm_enabled()) + params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS; + else + params->hcr_el2 = HCR_HOST_NVHE_FLAGS; + if (cpus_have_final_cap(ARM64_KVM_HVHE)) + params->hcr_el2 |= HCR_E2H; + params->vttbr = params->vtcr = 0; + + /* + * Flush the init params from the data cache because the struct will + * be read while the MMU is off. + */ + kvm_flush_dcache_to_poc(params, sizeof(*params)); +} + +static void hyp_install_host_vector(void) +{ + struct kvm_nvhe_init_params *params; + struct arm_smccc_res res; + + /* Switch from the HYP stub to our own HYP init vector */ + __hyp_set_vectors(kvm_get_idmap_vector()); + + /* + * Call initialization code, and switch to the full blown HYP code. + * If the cpucaps haven't been finalized yet, something has gone very + * wrong, and hyp will crash and burn when it uses any + * cpus_have_*_cap() wrapper. + */ + BUG_ON(!system_capabilities_finalized()); + params = this_cpu_ptr_nvhe_sym(kvm_init_params); + arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res); + WARN_ON(res.a0 != SMCCC_RET_SUCCESS); +} + +static void cpu_init_hyp_mode(void) +{ + hyp_install_host_vector(); + + /* + * Disabling SSBD on a non-VHE system requires us to enable SSBS + * at EL2. + */ + if (this_cpu_has_cap(ARM64_SSBS) && + arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) { + kvm_call_hyp_nvhe(__kvm_enable_ssbs); + } +} + +static void cpu_hyp_reset(void) +{ + if (!is_kernel_in_hyp_mode()) + __hyp_reset_vectors(); +} + +/* + * EL2 vectors can be mapped and rerouted in a number of ways, + * depending on the kernel configuration and CPU present: + * + * - If the CPU is affected by Spectre-v2, the hardening sequence is + * placed in one of the vector slots, which is executed before jumping + * to the real vectors. + * + * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot + * containing the hardening sequence is mapped next to the idmap page, + * and executed before jumping to the real vectors. + * + * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an + * empty slot is selected, mapped next to the idmap page, and + * executed before jumping to the real vectors. + * + * Note that ARM64_SPECTRE_V3A is somewhat incompatible with + * VHE, as we don't have hypervisor-specific mappings. If the system + * is VHE and yet selects this capability, it will be ignored. + */ +static void cpu_set_hyp_vector(void) +{ + struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data); + void *vector = hyp_spectre_vector_selector[data->slot]; + + if (!is_protected_kvm_enabled()) + *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector; + else + kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot); +} + +static void cpu_hyp_init_context(void) +{ + kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt); + + if (!is_kernel_in_hyp_mode()) + cpu_init_hyp_mode(); +} + +static void cpu_hyp_init_features(void) +{ + cpu_set_hyp_vector(); + kvm_arm_init_debug(); + + if (is_kernel_in_hyp_mode()) + kvm_timer_init_vhe(); + + if (vgic_present) + kvm_vgic_init_cpu_hardware(); +} + +static void cpu_hyp_reinit(void) +{ + cpu_hyp_reset(); + cpu_hyp_init_context(); + cpu_hyp_init_features(); +} + +static void cpu_hyp_init(void *discard) +{ + if (!__this_cpu_read(kvm_hyp_initialized)) { + cpu_hyp_reinit(); + __this_cpu_write(kvm_hyp_initialized, 1); + } +} + +static void cpu_hyp_uninit(void *discard) +{ + if (__this_cpu_read(kvm_hyp_initialized)) { + cpu_hyp_reset(); + __this_cpu_write(kvm_hyp_initialized, 0); + } +} + +int kvm_arch_hardware_enable(void) +{ + /* + * Most calls to this function are made with migration + * disabled, but not with preemption disabled. The former is + * enough to ensure correctness, but most of the helpers + * expect the later and will throw a tantrum otherwise. + */ + preempt_disable(); + + cpu_hyp_init(NULL); + + kvm_vgic_cpu_up(); + kvm_timer_cpu_up(); + + preempt_enable(); + + return 0; +} + +void kvm_arch_hardware_disable(void) +{ + kvm_timer_cpu_down(); + kvm_vgic_cpu_down(); + + if (!is_protected_kvm_enabled()) + cpu_hyp_uninit(NULL); +} + +#ifdef CONFIG_CPU_PM +static int hyp_init_cpu_pm_notifier(struct notifier_block *self, + unsigned long cmd, + void *v) +{ + /* + * kvm_hyp_initialized is left with its old value over + * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should + * re-enable hyp. + */ + switch (cmd) { + case CPU_PM_ENTER: + if (__this_cpu_read(kvm_hyp_initialized)) + /* + * don't update kvm_hyp_initialized here + * so that the hyp will be re-enabled + * when we resume. See below. + */ + cpu_hyp_reset(); + + return NOTIFY_OK; + case CPU_PM_ENTER_FAILED: + case CPU_PM_EXIT: + if (__this_cpu_read(kvm_hyp_initialized)) + /* The hyp was enabled before suspend. */ + cpu_hyp_reinit(); + + return NOTIFY_OK; + + default: + return NOTIFY_DONE; + } +} + +static struct notifier_block hyp_init_cpu_pm_nb = { + .notifier_call = hyp_init_cpu_pm_notifier, +}; + +static void __init hyp_cpu_pm_init(void) +{ + if (!is_protected_kvm_enabled()) + cpu_pm_register_notifier(&hyp_init_cpu_pm_nb); +} +static void __init hyp_cpu_pm_exit(void) +{ + if (!is_protected_kvm_enabled()) + cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb); +} +#else +static inline void __init hyp_cpu_pm_init(void) +{ +} +static inline void __init hyp_cpu_pm_exit(void) +{ +} +#endif + +static void __init init_cpu_logical_map(void) +{ + unsigned int cpu; + + /* + * Copy the MPIDR <-> logical CPU ID mapping to hyp. + * Only copy the set of online CPUs whose features have been checked + * against the finalized system capabilities. The hypervisor will not + * allow any other CPUs from the `possible` set to boot. + */ + for_each_online_cpu(cpu) + hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu); +} + +#define init_psci_0_1_impl_state(config, what) \ + config.psci_0_1_ ## what ## _implemented = psci_ops.what + +static bool __init init_psci_relay(void) +{ + /* + * If PSCI has not been initialized, protected KVM cannot install + * itself on newly booted CPUs. + */ + if (!psci_ops.get_version) { + kvm_err("Cannot initialize protected mode without PSCI\n"); + return false; + } + + kvm_host_psci_config.version = psci_ops.get_version(); + kvm_host_psci_config.smccc_version = arm_smccc_get_version(); + + if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) { + kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids(); + init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend); + init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on); + init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off); + init_psci_0_1_impl_state(kvm_host_psci_config, migrate); + } + return true; +} + +static int __init init_subsystems(void) +{ + int err = 0; + + /* + * Enable hardware so that subsystem initialisation can access EL2. + */ + on_each_cpu(cpu_hyp_init, NULL, 1); + + /* + * Register CPU lower-power notifier + */ + hyp_cpu_pm_init(); + + /* + * Init HYP view of VGIC + */ + err = kvm_vgic_hyp_init(); + switch (err) { + case 0: + vgic_present = true; + break; + case -ENODEV: + case -ENXIO: + vgic_present = false; + err = 0; + break; + default: + goto out; + } + + /* + * Init HYP architected timer support + */ + err = kvm_timer_hyp_init(vgic_present); + if (err) + goto out; + + kvm_register_perf_callbacks(NULL); + +out: + if (err) + hyp_cpu_pm_exit(); + + if (err || !is_protected_kvm_enabled()) + on_each_cpu(cpu_hyp_uninit, NULL, 1); + + return err; +} + +static void __init teardown_subsystems(void) +{ + kvm_unregister_perf_callbacks(); + hyp_cpu_pm_exit(); +} + +static void __init teardown_hyp_mode(void) +{ + int cpu; + + free_hyp_pgds(); + for_each_possible_cpu(cpu) { + free_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); + free_pages(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu], nvhe_percpu_order()); + } +} + +static int __init do_pkvm_init(u32 hyp_va_bits) +{ + void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)); + int ret; + + preempt_disable(); + cpu_hyp_init_context(); + ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size, + num_possible_cpus(), kern_hyp_va(per_cpu_base), + hyp_va_bits); + cpu_hyp_init_features(); + + /* + * The stub hypercalls are now disabled, so set our local flag to + * prevent a later re-init attempt in kvm_arch_hardware_enable(). + */ + __this_cpu_write(kvm_hyp_initialized, 1); + preempt_enable(); + + return ret; +} + +static u64 get_hyp_id_aa64pfr0_el1(void) +{ + /* + * Track whether the system isn't affected by spectre/meltdown in the + * hypervisor's view of id_aa64pfr0_el1, used for protected VMs. + * Although this is per-CPU, we make it global for simplicity, e.g., not + * to have to worry about vcpu migration. + * + * Unlike for non-protected VMs, userspace cannot override this for + * protected VMs. + */ + u64 val = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); + + val &= ~(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2) | + ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3)); + + val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2), + arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED); + val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3), + arm64_get_meltdown_state() == SPECTRE_UNAFFECTED); + + return val; +} + +static void kvm_hyp_init_symbols(void) +{ + kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = get_hyp_id_aa64pfr0_el1(); + kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1); + kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1); + kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1); + kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1); + kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); + kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); + kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1); + kvm_nvhe_sym(id_aa64smfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64SMFR0_EL1); + kvm_nvhe_sym(__icache_flags) = __icache_flags; + kvm_nvhe_sym(kvm_arm_vmid_bits) = kvm_arm_vmid_bits; +} + +static int __init kvm_hyp_init_protection(u32 hyp_va_bits) +{ + void *addr = phys_to_virt(hyp_mem_base); + int ret; + + ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP); + if (ret) + return ret; + + ret = do_pkvm_init(hyp_va_bits); + if (ret) + return ret; + + free_hyp_pgds(); + + return 0; +} + +static void pkvm_hyp_init_ptrauth(void) +{ + struct kvm_cpu_context *hyp_ctxt; + int cpu; + + for_each_possible_cpu(cpu) { + hyp_ctxt = per_cpu_ptr_nvhe_sym(kvm_hyp_ctxt, cpu); + hyp_ctxt->sys_regs[APIAKEYLO_EL1] = get_random_long(); + hyp_ctxt->sys_regs[APIAKEYHI_EL1] = get_random_long(); + hyp_ctxt->sys_regs[APIBKEYLO_EL1] = get_random_long(); + hyp_ctxt->sys_regs[APIBKEYHI_EL1] = get_random_long(); + hyp_ctxt->sys_regs[APDAKEYLO_EL1] = get_random_long(); + hyp_ctxt->sys_regs[APDAKEYHI_EL1] = get_random_long(); + hyp_ctxt->sys_regs[APDBKEYLO_EL1] = get_random_long(); + hyp_ctxt->sys_regs[APDBKEYHI_EL1] = get_random_long(); + hyp_ctxt->sys_regs[APGAKEYLO_EL1] = get_random_long(); + hyp_ctxt->sys_regs[APGAKEYHI_EL1] = get_random_long(); + } +} + +/* Inits Hyp-mode on all online CPUs */ +static int __init init_hyp_mode(void) +{ + u32 hyp_va_bits; + int cpu; + int err = -ENOMEM; + + /* + * The protected Hyp-mode cannot be initialized if the memory pool + * allocation has failed. + */ + if (is_protected_kvm_enabled() && !hyp_mem_base) + goto out_err; + + /* + * Allocate Hyp PGD and setup Hyp identity mapping + */ + err = kvm_mmu_init(&hyp_va_bits); + if (err) + goto out_err; + + /* + * Allocate stack pages for Hypervisor-mode + */ + for_each_possible_cpu(cpu) { + unsigned long stack_page; + + stack_page = __get_free_page(GFP_KERNEL); + if (!stack_page) { + err = -ENOMEM; + goto out_err; + } + + per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page; + } + + /* + * Allocate and initialize pages for Hypervisor-mode percpu regions. + */ + for_each_possible_cpu(cpu) { + struct page *page; + void *page_addr; + + page = alloc_pages(GFP_KERNEL, nvhe_percpu_order()); + if (!page) { + err = -ENOMEM; + goto out_err; + } + + page_addr = page_address(page); + memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size()); + kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu] = (unsigned long)page_addr; + } + + /* + * Map the Hyp-code called directly from the host + */ + err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start), + kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC); + if (err) { + kvm_err("Cannot map world-switch code\n"); + goto out_err; + } + + err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start), + kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO); + if (err) { + kvm_err("Cannot map .hyp.rodata section\n"); + goto out_err; + } + + err = create_hyp_mappings(kvm_ksym_ref(__start_rodata), + kvm_ksym_ref(__end_rodata), PAGE_HYP_RO); + if (err) { + kvm_err("Cannot map rodata section\n"); + goto out_err; + } + + /* + * .hyp.bss is guaranteed to be placed at the beginning of the .bss + * section thanks to an assertion in the linker script. Map it RW and + * the rest of .bss RO. + */ + err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start), + kvm_ksym_ref(__hyp_bss_end), PAGE_HYP); + if (err) { + kvm_err("Cannot map hyp bss section: %d\n", err); + goto out_err; + } + + err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end), + kvm_ksym_ref(__bss_stop), PAGE_HYP_RO); + if (err) { + kvm_err("Cannot map bss section\n"); + goto out_err; + } + + /* + * Map the Hyp stack pages + */ + for_each_possible_cpu(cpu) { + struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); + char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu); + + err = create_hyp_stack(__pa(stack_page), ¶ms->stack_hyp_va); + if (err) { + kvm_err("Cannot map hyp stack\n"); + goto out_err; + } + + /* + * Save the stack PA in nvhe_init_params. This will be needed + * to recreate the stack mapping in protected nVHE mode. + * __hyp_pa() won't do the right thing there, since the stack + * has been mapped in the flexible private VA space. + */ + params->stack_pa = __pa(stack_page); + } + + for_each_possible_cpu(cpu) { + char *percpu_begin = (char *)kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu]; + char *percpu_end = percpu_begin + nvhe_percpu_size(); + + /* Map Hyp percpu pages */ + err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP); + if (err) { + kvm_err("Cannot map hyp percpu region\n"); + goto out_err; + } + + /* Prepare the CPU initialization parameters */ + cpu_prepare_hyp_mode(cpu, hyp_va_bits); + } + + kvm_hyp_init_symbols(); + + if (is_protected_kvm_enabled()) { + if (IS_ENABLED(CONFIG_ARM64_PTR_AUTH_KERNEL) && + cpus_have_final_cap(ARM64_HAS_ADDRESS_AUTH)) + pkvm_hyp_init_ptrauth(); + + init_cpu_logical_map(); + + if (!init_psci_relay()) { + err = -ENODEV; + goto out_err; + } + + err = kvm_hyp_init_protection(hyp_va_bits); + if (err) { + kvm_err("Failed to init hyp memory protection\n"); + goto out_err; + } + } + + return 0; + +out_err: + teardown_hyp_mode(); + kvm_err("error initializing Hyp mode: %d\n", err); + return err; +} + +struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr) +{ + struct kvm_vcpu *vcpu; + unsigned long i; + + mpidr &= MPIDR_HWID_BITMASK; + + if (kvm->arch.mpidr_data) { + u16 idx = kvm_mpidr_index(kvm->arch.mpidr_data, mpidr); + + vcpu = kvm_get_vcpu(kvm, + kvm->arch.mpidr_data->cmpidr_to_idx[idx]); + if (mpidr != kvm_vcpu_get_mpidr_aff(vcpu)) + vcpu = NULL; + + return vcpu; + } + + kvm_for_each_vcpu(i, vcpu, kvm) { + if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu)) + return vcpu; + } + return NULL; +} + +bool kvm_arch_irqchip_in_kernel(struct kvm *kvm) +{ + return irqchip_in_kernel(kvm); +} + +bool kvm_arch_has_irq_bypass(void) +{ + return true; +} + +int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, + struct irq_bypass_producer *prod) +{ + struct kvm_kernel_irqfd *irqfd = + container_of(cons, struct kvm_kernel_irqfd, consumer); + + return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq, + &irqfd->irq_entry); +} +void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, + struct irq_bypass_producer *prod) +{ + struct kvm_kernel_irqfd *irqfd = + container_of(cons, struct kvm_kernel_irqfd, consumer); + + kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq, + &irqfd->irq_entry); +} + +void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons) +{ + struct kvm_kernel_irqfd *irqfd = + container_of(cons, struct kvm_kernel_irqfd, consumer); + + kvm_arm_halt_guest(irqfd->kvm); +} + +void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons) +{ + struct kvm_kernel_irqfd *irqfd = + container_of(cons, struct kvm_kernel_irqfd, consumer); + + kvm_arm_resume_guest(irqfd->kvm); +} + +/* Initialize Hyp-mode and memory mappings on all CPUs */ +static __init int kvm_arm_init(void) +{ + int err; + bool in_hyp_mode; + + if (!is_hyp_mode_available()) { + kvm_info("HYP mode not available\n"); + return -ENODEV; + } + + if (kvm_get_mode() == KVM_MODE_NONE) { + kvm_info("KVM disabled from command line\n"); + return -ENODEV; + } + + err = kvm_sys_reg_table_init(); + if (err) { + kvm_info("Error initializing system register tables"); + return err; + } + + in_hyp_mode = is_kernel_in_hyp_mode(); + + if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) || + cpus_have_final_cap(ARM64_WORKAROUND_1508412)) + kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \ + "Only trusted guests should be used on this system.\n"); + + err = kvm_set_ipa_limit(); + if (err) + return err; + + err = kvm_arm_init_sve(); + if (err) + return err; + + err = kvm_arm_vmid_alloc_init(); + if (err) { + kvm_err("Failed to initialize VMID allocator.\n"); + return err; + } + + if (!in_hyp_mode) { + err = init_hyp_mode(); + if (err) + goto out_err; + } + + err = kvm_init_vector_slots(); + if (err) { + kvm_err("Cannot initialise vector slots\n"); + goto out_hyp; + } + + err = init_subsystems(); + if (err) + goto out_hyp; + + if (is_protected_kvm_enabled()) { + kvm_info("Protected nVHE mode initialized successfully\n"); + } else if (in_hyp_mode) { + kvm_info("VHE mode initialized successfully\n"); + } else { + char mode = cpus_have_final_cap(ARM64_KVM_HVHE) ? 'h' : 'n'; + kvm_info("Hyp mode (%cVHE) initialized successfully\n", mode); + } + + /* + * FIXME: Do something reasonable if kvm_init() fails after pKVM + * hypervisor protection is finalized. + */ + err = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE); + if (err) + goto out_subs; + + kvm_arm_initialised = true; + + return 0; + +out_subs: + teardown_subsystems(); +out_hyp: + if (!in_hyp_mode) + teardown_hyp_mode(); +out_err: + kvm_arm_vmid_alloc_free(); + return err; +} + +static int __init early_kvm_mode_cfg(char *arg) +{ + if (!arg) + return -EINVAL; + + if (strcmp(arg, "none") == 0) { + kvm_mode = KVM_MODE_NONE; + return 0; + } + + if (!is_hyp_mode_available()) { + pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n"); + return 0; + } + + if (strcmp(arg, "protected") == 0) { + if (!is_kernel_in_hyp_mode()) + kvm_mode = KVM_MODE_PROTECTED; + else + pr_warn_once("Protected KVM not available with VHE\n"); + + return 0; + } + + if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) { + kvm_mode = KVM_MODE_DEFAULT; + return 0; + } + + if (strcmp(arg, "nested") == 0 && !WARN_ON(!is_kernel_in_hyp_mode())) { + kvm_mode = KVM_MODE_NV; + return 0; + } + + return -EINVAL; +} +early_param("kvm-arm.mode", early_kvm_mode_cfg); + +enum kvm_mode kvm_get_mode(void) +{ + return kvm_mode; +} + +module_init(kvm_arm_init); |