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-rw-r--r--virt/kvm/arm/psci.c564
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;
-}