diff options
Diffstat (limited to 'virt/kvm/arm/psci.c')
| -rw-r--r-- | virt/kvm/arm/psci.c | 564 |
1 files changed, 0 insertions, 564 deletions
diff --git a/virt/kvm/arm/psci.c b/virt/kvm/arm/psci.c deleted file mode 100644 index ae364716ee40..000000000000 --- a/virt/kvm/arm/psci.c +++ /dev/null @@ -1,564 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Copyright (C) 2012 - ARM Ltd - * Author: Marc Zyngier <marc.zyngier@arm.com> - */ - -#include <linux/arm-smccc.h> -#include <linux/preempt.h> -#include <linux/kvm_host.h> -#include <linux/uaccess.h> -#include <linux/wait.h> - -#include <asm/cputype.h> -#include <asm/kvm_emulate.h> - -#include <kvm/arm_psci.h> -#include <kvm/arm_hypercalls.h> - -/* - * This is an implementation of the Power State Coordination Interface - * as described in ARM document number ARM DEN 0022A. - */ - -#define AFFINITY_MASK(level) ~((0x1UL << ((level) * MPIDR_LEVEL_BITS)) - 1) - -static unsigned long psci_affinity_mask(unsigned long affinity_level) -{ - if (affinity_level <= 3) - return MPIDR_HWID_BITMASK & AFFINITY_MASK(affinity_level); - - return 0; -} - -static unsigned long kvm_psci_vcpu_suspend(struct kvm_vcpu *vcpu) -{ - /* - * NOTE: For simplicity, we make VCPU suspend emulation to be - * same-as WFI (Wait-for-interrupt) emulation. - * - * This means for KVM the wakeup events are interrupts and - * this is consistent with intended use of StateID as described - * in section 5.4.1 of PSCI v0.2 specification (ARM DEN 0022A). - * - * Further, we also treat power-down request to be same as - * stand-by request as-per section 5.4.2 clause 3 of PSCI v0.2 - * specification (ARM DEN 0022A). This means all suspend states - * for KVM will preserve the register state. - */ - kvm_vcpu_block(vcpu); - kvm_clear_request(KVM_REQ_UNHALT, vcpu); - - return PSCI_RET_SUCCESS; -} - -static void kvm_psci_vcpu_off(struct kvm_vcpu *vcpu) -{ - vcpu->arch.power_off = true; - kvm_make_request(KVM_REQ_SLEEP, vcpu); - kvm_vcpu_kick(vcpu); -} - -static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) -{ - struct vcpu_reset_state *reset_state; - struct kvm *kvm = source_vcpu->kvm; - struct kvm_vcpu *vcpu = NULL; - unsigned long cpu_id; - - cpu_id = smccc_get_arg1(source_vcpu) & MPIDR_HWID_BITMASK; - if (vcpu_mode_is_32bit(source_vcpu)) - cpu_id &= ~((u32) 0); - - vcpu = kvm_mpidr_to_vcpu(kvm, cpu_id); - - /* - * Make sure the caller requested a valid CPU and that the CPU is - * turned off. - */ - if (!vcpu) - return PSCI_RET_INVALID_PARAMS; - if (!vcpu->arch.power_off) { - if (kvm_psci_version(source_vcpu, kvm) != KVM_ARM_PSCI_0_1) - return PSCI_RET_ALREADY_ON; - else - return PSCI_RET_INVALID_PARAMS; - } - - reset_state = &vcpu->arch.reset_state; - - reset_state->pc = smccc_get_arg2(source_vcpu); - - /* Propagate caller endianness */ - reset_state->be = kvm_vcpu_is_be(source_vcpu); - - /* - * NOTE: We always update r0 (or x0) because for PSCI v0.1 - * the general puspose registers are undefined upon CPU_ON. - */ - reset_state->r0 = smccc_get_arg3(source_vcpu); - - WRITE_ONCE(reset_state->reset, true); - kvm_make_request(KVM_REQ_VCPU_RESET, vcpu); - - /* - * Make sure the reset request is observed if the change to - * power_state is observed. - */ - smp_wmb(); - - vcpu->arch.power_off = false; - kvm_vcpu_wake_up(vcpu); - - return PSCI_RET_SUCCESS; -} - -static unsigned long kvm_psci_vcpu_affinity_info(struct kvm_vcpu *vcpu) -{ - int i, matching_cpus = 0; - unsigned long mpidr; - unsigned long target_affinity; - unsigned long target_affinity_mask; - unsigned long lowest_affinity_level; - struct kvm *kvm = vcpu->kvm; - struct kvm_vcpu *tmp; - - target_affinity = smccc_get_arg1(vcpu); - lowest_affinity_level = smccc_get_arg2(vcpu); - - /* Determine target affinity mask */ - target_affinity_mask = psci_affinity_mask(lowest_affinity_level); - if (!target_affinity_mask) - return PSCI_RET_INVALID_PARAMS; - - /* Ignore other bits of target affinity */ - target_affinity &= target_affinity_mask; - - /* - * If one or more VCPU matching target affinity are running - * then ON else OFF - */ - kvm_for_each_vcpu(i, tmp, kvm) { - mpidr = kvm_vcpu_get_mpidr_aff(tmp); - if ((mpidr & target_affinity_mask) == target_affinity) { - matching_cpus++; - if (!tmp->arch.power_off) - return PSCI_0_2_AFFINITY_LEVEL_ON; - } - } - - if (!matching_cpus) - return PSCI_RET_INVALID_PARAMS; - - return PSCI_0_2_AFFINITY_LEVEL_OFF; -} - -static void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type) -{ - int i; - struct kvm_vcpu *tmp; - - /* - * The KVM ABI specifies that a system event exit may call KVM_RUN - * again and may perform shutdown/reboot at a later time that when the - * actual request is made. Since we are implementing PSCI and a - * caller of PSCI reboot and shutdown expects that the system shuts - * down or reboots immediately, let's make sure that VCPUs are not run - * after this call is handled and before the VCPUs have been - * re-initialized. - */ - kvm_for_each_vcpu(i, tmp, vcpu->kvm) - tmp->arch.power_off = true; - kvm_make_all_cpus_request(vcpu->kvm, KVM_REQ_SLEEP); - - memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event)); - vcpu->run->system_event.type = type; - vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; -} - -static void kvm_psci_system_off(struct kvm_vcpu *vcpu) -{ - kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_SHUTDOWN); -} - -static void kvm_psci_system_reset(struct kvm_vcpu *vcpu) -{ - kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_RESET); -} - -static void kvm_psci_narrow_to_32bit(struct kvm_vcpu *vcpu) -{ - int i; - - /* - * Zero the input registers' upper 32 bits. They will be fully - * zeroed on exit, so we're fine changing them in place. - */ - for (i = 1; i < 4; i++) - vcpu_set_reg(vcpu, i, lower_32_bits(vcpu_get_reg(vcpu, i))); -} - -static unsigned long kvm_psci_check_allowed_function(struct kvm_vcpu *vcpu, u32 fn) -{ - switch(fn) { - case PSCI_0_2_FN64_CPU_SUSPEND: - case PSCI_0_2_FN64_CPU_ON: - case PSCI_0_2_FN64_AFFINITY_INFO: - /* Disallow these functions for 32bit guests */ - if (vcpu_mode_is_32bit(vcpu)) - return PSCI_RET_NOT_SUPPORTED; - break; - } - - return 0; -} - -static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu) -{ - struct kvm *kvm = vcpu->kvm; - u32 psci_fn = smccc_get_function(vcpu); - unsigned long val; - int ret = 1; - - val = kvm_psci_check_allowed_function(vcpu, psci_fn); - if (val) - goto out; - - switch (psci_fn) { - case PSCI_0_2_FN_PSCI_VERSION: - /* - * Bits[31:16] = Major Version = 0 - * Bits[15:0] = Minor Version = 2 - */ - val = KVM_ARM_PSCI_0_2; - break; - case PSCI_0_2_FN_CPU_SUSPEND: - case PSCI_0_2_FN64_CPU_SUSPEND: - val = kvm_psci_vcpu_suspend(vcpu); - break; - case PSCI_0_2_FN_CPU_OFF: - kvm_psci_vcpu_off(vcpu); - val = PSCI_RET_SUCCESS; - break; - case PSCI_0_2_FN_CPU_ON: - kvm_psci_narrow_to_32bit(vcpu); - fallthrough; - case PSCI_0_2_FN64_CPU_ON: - mutex_lock(&kvm->lock); - val = kvm_psci_vcpu_on(vcpu); - mutex_unlock(&kvm->lock); - break; - case PSCI_0_2_FN_AFFINITY_INFO: - kvm_psci_narrow_to_32bit(vcpu); - fallthrough; - case PSCI_0_2_FN64_AFFINITY_INFO: - val = kvm_psci_vcpu_affinity_info(vcpu); - break; - case PSCI_0_2_FN_MIGRATE_INFO_TYPE: - /* - * Trusted OS is MP hence does not require migration - * or - * Trusted OS is not present - */ - val = PSCI_0_2_TOS_MP; - break; - case PSCI_0_2_FN_SYSTEM_OFF: - kvm_psci_system_off(vcpu); - /* - * We should'nt be going back to guest VCPU after - * receiving SYSTEM_OFF request. - * - * If user space accidently/deliberately resumes - * guest VCPU after SYSTEM_OFF request then guest - * VCPU should see internal failure from PSCI return - * value. To achieve this, we preload r0 (or x0) with - * PSCI return value INTERNAL_FAILURE. - */ - val = PSCI_RET_INTERNAL_FAILURE; - ret = 0; - break; - case PSCI_0_2_FN_SYSTEM_RESET: - kvm_psci_system_reset(vcpu); - /* - * Same reason as SYSTEM_OFF for preloading r0 (or x0) - * with PSCI return value INTERNAL_FAILURE. - */ - val = PSCI_RET_INTERNAL_FAILURE; - ret = 0; - break; - default: - val = PSCI_RET_NOT_SUPPORTED; - break; - } - -out: - smccc_set_retval(vcpu, val, 0, 0, 0); - return ret; -} - -static int kvm_psci_1_0_call(struct kvm_vcpu *vcpu) -{ - u32 psci_fn = smccc_get_function(vcpu); - u32 feature; - unsigned long val; - int ret = 1; - - switch(psci_fn) { - case PSCI_0_2_FN_PSCI_VERSION: - val = KVM_ARM_PSCI_1_0; - break; - case PSCI_1_0_FN_PSCI_FEATURES: - feature = smccc_get_arg1(vcpu); - val = kvm_psci_check_allowed_function(vcpu, feature); - if (val) - break; - - switch(feature) { - case PSCI_0_2_FN_PSCI_VERSION: - case PSCI_0_2_FN_CPU_SUSPEND: - case PSCI_0_2_FN64_CPU_SUSPEND: - case PSCI_0_2_FN_CPU_OFF: - case PSCI_0_2_FN_CPU_ON: - case PSCI_0_2_FN64_CPU_ON: - case PSCI_0_2_FN_AFFINITY_INFO: - case PSCI_0_2_FN64_AFFINITY_INFO: - case PSCI_0_2_FN_MIGRATE_INFO_TYPE: - case PSCI_0_2_FN_SYSTEM_OFF: - case PSCI_0_2_FN_SYSTEM_RESET: - case PSCI_1_0_FN_PSCI_FEATURES: - case ARM_SMCCC_VERSION_FUNC_ID: - val = 0; - break; - default: - val = PSCI_RET_NOT_SUPPORTED; - break; - } - break; - default: - return kvm_psci_0_2_call(vcpu); - } - - smccc_set_retval(vcpu, val, 0, 0, 0); - return ret; -} - -static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu) -{ - struct kvm *kvm = vcpu->kvm; - u32 psci_fn = smccc_get_function(vcpu); - unsigned long val; - - switch (psci_fn) { - case KVM_PSCI_FN_CPU_OFF: - kvm_psci_vcpu_off(vcpu); - val = PSCI_RET_SUCCESS; - break; - case KVM_PSCI_FN_CPU_ON: - mutex_lock(&kvm->lock); - val = kvm_psci_vcpu_on(vcpu); - mutex_unlock(&kvm->lock); - break; - default: - val = PSCI_RET_NOT_SUPPORTED; - break; - } - - smccc_set_retval(vcpu, val, 0, 0, 0); - return 1; -} - -/** - * kvm_psci_call - handle PSCI call if r0 value is in range - * @vcpu: Pointer to the VCPU struct - * - * Handle PSCI calls from guests through traps from HVC instructions. - * The calling convention is similar to SMC calls to the secure world - * where the function number is placed in r0. - * - * This function returns: > 0 (success), 0 (success but exit to user - * space), and < 0 (errors) - * - * Errors: - * -EINVAL: Unrecognized PSCI function - */ -int kvm_psci_call(struct kvm_vcpu *vcpu) -{ - switch (kvm_psci_version(vcpu, vcpu->kvm)) { - case KVM_ARM_PSCI_1_0: - return kvm_psci_1_0_call(vcpu); - case KVM_ARM_PSCI_0_2: - return kvm_psci_0_2_call(vcpu); - case KVM_ARM_PSCI_0_1: - return kvm_psci_0_1_call(vcpu); - default: - return -EINVAL; - }; -} - -int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu) -{ - return 3; /* PSCI version and two workaround registers */ -} - -int kvm_arm_copy_fw_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices) -{ - if (put_user(KVM_REG_ARM_PSCI_VERSION, uindices++)) - return -EFAULT; - - if (put_user(KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1, uindices++)) - return -EFAULT; - - if (put_user(KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2, uindices++)) - return -EFAULT; - - return 0; -} - -#define KVM_REG_FEATURE_LEVEL_WIDTH 4 -#define KVM_REG_FEATURE_LEVEL_MASK (BIT(KVM_REG_FEATURE_LEVEL_WIDTH) - 1) - -/* - * Convert the workaround level into an easy-to-compare number, where higher - * values mean better protection. - */ -static int get_kernel_wa_level(u64 regid) -{ - switch (regid) { - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1: - switch (kvm_arm_harden_branch_predictor()) { - case KVM_BP_HARDEN_UNKNOWN: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_AVAIL; - case KVM_BP_HARDEN_WA_NEEDED: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_AVAIL; - case KVM_BP_HARDEN_NOT_REQUIRED: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_REQUIRED; - } - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_AVAIL; - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2: - switch (kvm_arm_have_ssbd()) { - case KVM_SSBD_FORCE_DISABLE: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL; - case KVM_SSBD_KERNEL: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL; - case KVM_SSBD_FORCE_ENABLE: - case KVM_SSBD_MITIGATED: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED; - case KVM_SSBD_UNKNOWN: - default: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_UNKNOWN; - } - } - - return -EINVAL; -} - -int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) -{ - void __user *uaddr = (void __user *)(long)reg->addr; - u64 val; - - switch (reg->id) { - case KVM_REG_ARM_PSCI_VERSION: - val = kvm_psci_version(vcpu, vcpu->kvm); - break; - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1: - val = get_kernel_wa_level(reg->id) & KVM_REG_FEATURE_LEVEL_MASK; - break; - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2: - val = get_kernel_wa_level(reg->id) & KVM_REG_FEATURE_LEVEL_MASK; - - if (val == KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL && - kvm_arm_get_vcpu_workaround_2_flag(vcpu)) - val |= KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED; - break; - default: - return -ENOENT; - } - - if (copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id))) - return -EFAULT; - - return 0; -} - -int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) -{ - void __user *uaddr = (void __user *)(long)reg->addr; - u64 val; - int wa_level; - - if (copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id))) - return -EFAULT; - - switch (reg->id) { - case KVM_REG_ARM_PSCI_VERSION: - { - bool wants_02; - - wants_02 = test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features); - - switch (val) { - case KVM_ARM_PSCI_0_1: - if (wants_02) - return -EINVAL; - vcpu->kvm->arch.psci_version = val; - return 0; - case KVM_ARM_PSCI_0_2: - case KVM_ARM_PSCI_1_0: - if (!wants_02) - return -EINVAL; - vcpu->kvm->arch.psci_version = val; - return 0; - } - break; - } - - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1: - if (val & ~KVM_REG_FEATURE_LEVEL_MASK) - return -EINVAL; - - if (get_kernel_wa_level(reg->id) < val) - return -EINVAL; - - return 0; - - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2: - if (val & ~(KVM_REG_FEATURE_LEVEL_MASK | - KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED)) - return -EINVAL; - - wa_level = val & KVM_REG_FEATURE_LEVEL_MASK; - - if (get_kernel_wa_level(reg->id) < wa_level) - return -EINVAL; - - /* The enabled bit must not be set unless the level is AVAIL. */ - if (wa_level != KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL && - wa_level != val) - return -EINVAL; - - /* Are we finished or do we need to check the enable bit ? */ - if (kvm_arm_have_ssbd() != KVM_SSBD_KERNEL) - return 0; - - /* - * If this kernel supports the workaround to be switched on - * or off, make sure it matches the requested setting. - */ - switch (wa_level) { - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL: - kvm_arm_set_vcpu_workaround_2_flag(vcpu, - val & KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED); - break; - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED: - kvm_arm_set_vcpu_workaround_2_flag(vcpu, true); - break; - } - - return 0; - default: - return -ENOENT; - } - - return -EINVAL; -} |