512 lines
12 KiB
C
Executable file
512 lines
12 KiB
C
Executable file
/*
|
|
* Copyright (C) 2012 - ARM Ltd
|
|
* Author: Marc Zyngier <marc.zyngier@arm.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#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 <asm/kvm_host.h>
|
|
|
|
#include <kvm/arm_psci.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 u32 smccc_get_function(struct kvm_vcpu *vcpu)
|
|
{
|
|
return vcpu_get_reg(vcpu, 0);
|
|
}
|
|
|
|
static unsigned long smccc_get_arg1(struct kvm_vcpu *vcpu)
|
|
{
|
|
return vcpu_get_reg(vcpu, 1);
|
|
}
|
|
|
|
static unsigned long smccc_get_arg2(struct kvm_vcpu *vcpu)
|
|
{
|
|
return vcpu_get_reg(vcpu, 2);
|
|
}
|
|
|
|
static unsigned long smccc_get_arg3(struct kvm_vcpu *vcpu)
|
|
{
|
|
return vcpu_get_reg(vcpu, 3);
|
|
}
|
|
|
|
static void smccc_set_retval(struct kvm_vcpu *vcpu,
|
|
unsigned long a0,
|
|
unsigned long a1,
|
|
unsigned long a2,
|
|
unsigned long a3)
|
|
{
|
|
vcpu_set_reg(vcpu, 0, a0);
|
|
vcpu_set_reg(vcpu, 1, a1);
|
|
vcpu_set_reg(vcpu, 2, a2);
|
|
vcpu_set_reg(vcpu, 3, a3);
|
|
}
|
|
|
|
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 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;
|
|
|
|
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:
|
|
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:
|
|
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;
|
|
}
|
|
|
|
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);
|
|
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
|
|
*/
|
|
static 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_hvc_call_handler(struct kvm_vcpu *vcpu)
|
|
{
|
|
u32 func_id = smccc_get_function(vcpu);
|
|
u32 val = SMCCC_RET_NOT_SUPPORTED;
|
|
u32 feature;
|
|
|
|
switch (func_id) {
|
|
case ARM_SMCCC_VERSION_FUNC_ID:
|
|
val = ARM_SMCCC_VERSION_1_1;
|
|
break;
|
|
case ARM_SMCCC_ARCH_FEATURES_FUNC_ID:
|
|
feature = smccc_get_arg1(vcpu);
|
|
switch(feature) {
|
|
case ARM_SMCCC_ARCH_WORKAROUND_1:
|
|
if (kvm_arm_harden_branch_predictor())
|
|
val = SMCCC_RET_SUCCESS;
|
|
break;
|
|
case ARM_SMCCC_ARCH_WORKAROUND_2:
|
|
switch (kvm_arm_have_ssbd()) {
|
|
case KVM_SSBD_FORCE_DISABLE:
|
|
case KVM_SSBD_UNKNOWN:
|
|
break;
|
|
case KVM_SSBD_KERNEL:
|
|
val = SMCCC_RET_SUCCESS;
|
|
break;
|
|
case KVM_SSBD_FORCE_ENABLE:
|
|
case KVM_SSBD_MITIGATED:
|
|
val = SMCCC_RET_NOT_REQUIRED;
|
|
break;
|
|
}
|
|
break;
|
|
case ARM_SMCCC_ARCH_WORKAROUND_3:
|
|
switch (kvm_arm_get_spectre_bhb_state()) {
|
|
case SPECTRE_VULNERABLE:
|
|
break;
|
|
case SPECTRE_MITIGATED:
|
|
val = SMCCC_RET_SUCCESS;
|
|
break;
|
|
case SPECTRE_UNAFFECTED:
|
|
val = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED;
|
|
break;
|
|
}
|
|
break;
|
|
}
|
|
break;
|
|
default:
|
|
return kvm_psci_call(vcpu);
|
|
}
|
|
|
|
smccc_set_retval(vcpu, val, 0, 0, 0);
|
|
return 1;
|
|
}
|
|
|
|
int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu)
|
|
{
|
|
return 1; /* PSCI version */
|
|
}
|
|
|
|
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;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
|
|
{
|
|
if (reg->id == KVM_REG_ARM_PSCI_VERSION) {
|
|
void __user *uaddr = (void __user *)(long)reg->addr;
|
|
u64 val;
|
|
|
|
val = kvm_psci_version(vcpu, vcpu->kvm);
|
|
if (copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id)))
|
|
return -EFAULT;
|
|
|
|
return 0;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
|
|
{
|
|
if (reg->id == KVM_REG_ARM_PSCI_VERSION) {
|
|
void __user *uaddr = (void __user *)(long)reg->addr;
|
|
bool wants_02;
|
|
u64 val;
|
|
|
|
if (copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id)))
|
|
return -EFAULT;
|
|
|
|
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;
|
|
}
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|