diff options
Diffstat (limited to 'virt/kvm/arm/psci.c')
| -rw-r--r-- | virt/kvm/arm/psci.c | 503 |
1 files changed, 0 insertions, 503 deletions
diff --git a/virt/kvm/arm/psci.c b/virt/kvm/arm/psci.c deleted file mode 100644 index 9b73d3ad918a..000000000000 --- a/virt/kvm/arm/psci.c +++ /dev/null @@ -1,503 +0,0 @@ -/* - * 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 kvm *kvm = source_vcpu->kvm; - struct kvm_vcpu *vcpu = NULL; - struct swait_queue_head *wq; - unsigned long cpu_id; - unsigned long context_id; - phys_addr_t target_pc; - - 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; - } - - target_pc = smccc_get_arg2(source_vcpu); - context_id = smccc_get_arg3(source_vcpu); - - kvm_reset_vcpu(vcpu); - - /* Gracefully handle Thumb2 entry point */ - if (vcpu_mode_is_32bit(vcpu) && (target_pc & 1)) { - target_pc &= ~((phys_addr_t) 1); - vcpu_set_thumb(vcpu); - } - - /* Propagate caller endianness */ - if (kvm_vcpu_is_be(source_vcpu)) - kvm_vcpu_set_be(vcpu); - - *vcpu_pc(vcpu) = target_pc; - /* - * NOTE: We always update r0 (or x0) because for PSCI v0.1 - * the general puspose registers are undefined upon CPU_ON. - */ - smccc_set_retval(vcpu, context_id, 0, 0, 0); - vcpu->arch.power_off = false; - smp_mb(); /* Make sure the above is visible */ - - wq = kvm_arch_vcpu_wq(vcpu); - swake_up_one(wq); - - 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; - } - 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; -} |
